摘要:

PROCEEDINGS OF THE SOCIETY OF PUBLIC ANALYSTS. THE monthly meeting of the Society was held on Wednesday evening, June 1, in the Chemical Socieby’s Rooms, Burlington House. The chair was occupied suc- cessively by the President, Mr. Thomas Fairley, and by Mr. Otto Hehner. The minutes of the previous meeting were read and confirmed. A certificate of proposal for election to membership in favour of Mr. H. S. Hammond was read for the second time. Messrs. A. E. Brown, B.Sc., and L. G. Paul, Ph.D., were elected members of the Society. The PRESIDENT, referring to the late Professor A. W. Williamson, F.R.S., eaid that by his death, which had occurred since the last meeting, the Society had lost one of its honorary members who was probably the most prominent English chemist of his day, and whose discovery of the double ethers led to the evolution of the modern theory of atomicity. He proposed, on behalf of the Society, to send to Dr. Williameon’s relatives a letter of sympathy. The following papers were then read : ‘‘ Roasted Beetroot,” by E. G. Clayton ; ‘‘ The Analysis of Sweetened Condensed Milk,” by J. B. P. Harrison ; ‘‘ A Collection of Readings with the Zeiss OleeButyrometer,” by W. Chattaway and C . G. Moor, M.A.; and a “Note on the Estimation of Sugars and Starch in Vegetable Sub- stances,” by John S. Ford. Mr. Chattaway showed an improved form of tin for the collection of samples under the Sale of Food and Drugs Act.

ISSN:0003-2654    

DOI:10.1039/AN904290205b

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

20 6 THE ANALYST. NOTE ON SOME PHYSICAL CONSTANTS OBTAINED WITH MARGARINE. BY EDWARD RUSSELL, B.Sc., F.I.C., AND V. H. KIRKHAM, B.Sc. (Rend n t the Neeting, iUay 4, 1904.) IN the ordinary examination of samples of margarine, and of suspected butters which eventually were found to be margarine, we were struck with the considerable variations in the figures given by various samples when using the Zeiss butyro- refractometer. Using the arbitrary theymometric scale, and regarding the readings as + or - in relation to this, a marked + reading on the examination of a butter-fat indicates the presence of foreign fat. We found this reading for adulterated butters and margarines to vary between the wide limits of +3*5 and +9*5 ; and on testing for the presence of cotton-seed oil by the reduction test, the darkening was very much more marked in the case of those giving the high figure.We failed to detect sesame oil by the furfural test. It seemed, therefore, evident that some of thew samples-viz., those giving the high readings--contained considerable proportions of cotton-seed oil, and in certain cases we determined other constants, and also those for a mixture of one of the samples giving a low reading with 25 per cent. of cotton- seed oil, with a view to estimating roughly the amount of this constituent present in the margarine. The results are given in the following table : Sample. Valents figure (degroes Centigrade) Reichert figure- - - - - Water - - - . - - Butyro-refraetonieter .reading - Oleo-refractometer ,, - - Iodineabsorption - - - - 56 1 95 S2 1 SS 0'9 1'1 - , -.- 6 1 - 1 3 -4 - 0 13. 14. ~- (52 S(i 18.7 -221-4.: 4S'5 I __ 15. Sani1)le 7 is a niixtiire of' sample 6 with 25 per cent. cotton-seed oil. Samplc 16 is cotton-seed oil. The number of data collected in this table is somewhat meagre, but still, we think, sufficient to demonstr;tte the considerable variations in the composition of margarine. Taking each of the constants separately, we can see the difference produced by the introduction of vegetable oil. 1. Vulcizta E'igwc.--Readings above 89" C. are obtained when ouly traces of butter-fat or cotton-seed oil are present. The lowering of the figure produced by cotton-seed oil is much less than that produced by admixture with butter-fat. This is exactly what one would expect, seeing that the Valenta figure for cotton-seed oil is 69" C., and that for butter-fat 30" c. 2.BiitLlro-,.efr.actometer.-The figures in the table for this constant range between 2.7 and 9.4. It will be seen that the presence of butter-fat here reduces the reading,THE ANALYST. 207 and the presence of the vegetable oil increases it. This latter fact is proved by the high figure obtained with one of the margarines when 25 per cent. of cotton-seed oil had been added to it. These figures have the same meaning as the above. The cotton-seed oil itself gives 8 + reading. 4. Iodine dbsorption.-Only a few figures were obtained for this, but they bear out the conclusions suggested by consideration of the physical constants. The two points suggested by a consideration of these figures are : (1) A method for arriving at the amount of vegetable oil present, and (2) to what extent should such addition be permitted.Assuming that margarine is a substance derived from oleomargarine by admix- ture with a small amount of vegetable oil, we may calculate the extent of that addition by taking the figure for oleo-margarine and the figure obtained for cotton-seed oil in the oleo-refractometer, the difference between these two figures representing per- centages of vegetable oil added to an oleo-margarine. Thus a sample of margarine giving the reading - 13 contains less than 10 per cent. X sample giving the reading - 4 contains about 38 per cent. This is proved to be approximately correct by the figures given by a mixture of the first sample with 25 per cent.cotton-seed oil. This gave a figure of -6, corresponding to 33 per cent. cotton-seed oil. The figure taken for oleo-margarine is that given by Lewkowitsch. The amount of cotton-seed oil can thus easily be deduced, and there would be no difficulty in fixing a limit for administrative purposes. Referring again to the table, we see that the amount of water varies from 9 to 18 per cent. Hence we have another substance whose presence in excess in mar- garine is undesirable. Legally the word (6 margarine ” means all substances prepared in imitation of butter, whether mixed with butter or not, with the proviso that it shall not contain more than 10 per cent. butter-fat, We venture to suggest some further attempt might be made to fix its composition more nearly, that it might be regarded as oleo-mar- garine, containing not more than 10 per cent.butter-fat, 10 per cent. vegetable oil, and 10 per cent. water. DISCUSSION. 3. Obo-refractometer. -The readings range between - 22 and - 4. hlr. BEVAN inquired what was the authors’ objection to the use of cotton-seed oil. I t seemed to him that if margarine had to be made, it might as well be made with cotton-seed oil as with any other substitute for butter. Mr. HEHNEH said that margarine as defined in the Nargarine Act was any fatty substance made in imitation of butter. Consequently, the law allowed the margarine manufacturer to use anything of a fatty nature that could be made to look like butter, and it was well known that there were four or five different kinds of margarine.Originally margarine-the so-called oleo-margarine-was all animal fat, namely, pressed beef and pig fat. Then that was mixed with earth-nut oil to give a cheaper grade. Later sesame oil and cotton-seed oil were used, while the most modern variety was made with cocoanut oil. The use of all these materials208 THE ANALYST. was regulated by their price, and no suggestion had ever before been made that the quantity of any of them should be limited, and he saw no reason why it should. They were all perfectly wholesome, and, from an analytical point of view, the more vegetable oil that was used in margarine the better. He had hoped that the authors would deal with the question of the compulsory limitation of the quantity of butter fat in margarine. Since the report made in 1900 by the principal chemist of the Government Laboratory and a committee of the Society of Public Analysts a change had taken place in the manufacture of margarine.Some of the largest manufacturers now used 40 per cent. or more of cocoanut oil, and margarine so made, although it might not contain any butter fat at all, analgsed, as far as its proportion of volatile fatty acids was concerned, as though it contained a considerable proportion of butter fat; so that too implicit reliance must not now be placed on the Reichert-WoIlny figure in judging whether margarine complied with the Sale of Food and Drugs Act, 1899. I t seemed advisable, in view of thia recent development, that the process worked out by Dr. Thorye in conjunction with the Society should be modified. Mr. BEVAN pointed out tbat a recommendation that a certain process should be adopted did not render it officially binding. Mr. HEHXER said that it was adopted by a vote of the Society, and was published in the Report of the Local Government Board. I t was quasi-official, though not statutory. The PRESIDENT said that this showed the difficulty of fixing any standard process or limits. Mr. HEHNER : And the need for B permanent committee of reference which the Society had pressed so strongly upon Parliament. Mr. RUESELL, in reply, said that he agreed with what Mr. Hehner had said as to the legal definition of margarine. Other butter substitutes, however, were now being sold for which it was claimed that they were not ordinary margarine, but something else; and seeing that ordinary margarine was presumed to be primarily animal fat with a certain quantity of vegetable fat, he had thought it desirable to draw attention to the fact that these cheaper kinds had latterly been manufactured, which, in his opinion, should be sold under some special name.

ISSN:0003-2654    

DOI:10.1039/AN9042900206

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

208 THE ANALYST. NOTE ON MUSHROOM KETCHUP. BY J. F. LIVERSEEGE, F.I.C. (Read at the Mccting, Jfap 4, 1904.) LAET year I required information as to the composition of mushroom ketchup, but on consulting numerous books I failed to find a single analysis. According to cookery books mushroom ketchup is made by sprinkling salt on mushrooms, allowing to stand some days, and boiling the liquid which is produced with spices. I obtained samples from two different makers in July; they were nearly twelve montha old, as it was too early in the year for new ketchup. The samples contained a notable quantity of sediment, and were filtered before analysis. One of theTHE ANALYST. 209 sediments was microecopically examined, and found to be mainly composed of small oval bodies, probably spores.The analytical results, expressed in grammes per 100 c.c., were as follows : A. B. Specific gravity ... ... ... ... 1.05 ... 1.07 Organic solids ... ... ... ... ... 6.3 ... 4.0 Chlorides, calculated ae'NaC1' ' ... ... 2.6 ... 7.6 Phosphates, calculated 'as (PO,) . . ... 0.48 ... 0.44 Nitrogen ... ... ... ... ... 0.7 ... 0.6 Acidity, calculated as acetic acid ... ... 0.7 ... 0.3 Ash ... ... ... 4.0 ... 8.7 Difference ... ... ... ... 1.4 ... 1.1 - DISCUSSION. Mr. G. RUDD THOMPSON said that in Monmouthshire, where small farmers made considerabb quantities of mushroom ketchup for their own use, the process of manufacture was similar to that mentioned by the author, but with a very curious addition, namely, dried pig's liver. The pig's liver was dried up by heat-toasted, in fact-and then ground in a mortar or between two stones, and a, small quantity added to the ketchup.As a rule about 3 per cent. of the organic solids of such ketchup consisted of this dried pig's liver. In the residue under the microscope this carbonaceous matter appeared like fine charcoal, being powdery and structure- less. The more highly torrefied the liver was the more highly its effects seemed to be appreciated by the local producers. Mr. RICHMOND inquired whether any of the liver cells could be seen under the microscope in the cases to which Mr. Thompson referred. Mr. SEYLER observed that it would have been interesting to know whether any of these samples contained preservatives. Dr. SCHIDROWITZ remarked that if the nitrogen in Sample B were multiplied by the usual albuminoid factor, it would be seen that nearly the whole of the organic s o l i h o u l d be albuminnids.Mr. THOMPSON, in replying to Mr. Richmond's question, said that in the few samples he had examined he had obeerved no trace of cellular structure which would identify the pig's liver, owing to the high degree to which it was considered necessary to heat the liver in order to develop the full flavour in the ketchup. With regard to the queRtion of preservatives, some time ago he had occasion to examine a number of samples of sauces and table condiments, including two simples of mnsh- room ketchup by well-known makers, in both of which weighable quantities of boric acid had been found. The proportion of total solids in these borated samples was con- siderably larger than in the samples referred to in the present paper, the ketchup being much thicker. In Sample .A the difference was somewhat greater. AUTHOR'S NoTE.-Both samples were free from borates.

ISSN:0003-2654    

DOI:10.1039/AN9042900208

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

2 10 THE ANALYST. COD-LIVER OIL AND OTHER FISH OILS. BY J. F. LIVERSEEGE, F.I.C. (Read at the Meeting, May 4, 1904.) MY attention was called to the question of the adulteration of cod-liver oil by some samples which were submitted to me officially early last year. On looking up the matter, I found that analyses of cod-liver oil adulterants were scarce and incomplete. I therefore obtained a number of samples and analysed them. At a subsequent date the late Mr. J. Barclay kindly sent me samples of brusmer, hoi, and ling oils; which he informed me had been prepared in Norway from the fish indicated. As I could find no record of the two former names, I asked Professor Bridge, of the Birmingham University, for help. He kindly informed me that " brusmer " was probably the L' brismak " of the Shetlands, or Brosmiz~s brosma, one of the Gadide or cod family. He could not speak positively with regard to '' hoi," but suggested it might be the common piked dog-fish, one of the shark tribe, which is known in the Orkneys as hoe." For comparative purposes three samples of vegetable oil were also examined.Table A gives the analytical figures of the samples of cod-liver oil. Samples A and B were two qualities from the same wholesale house. The Newfoundland oil E differed in several respects from the other samples. I communicated with the wholesale house as to its genuineness, and was assured that it was obtained from ;I reliable Newfoundland firm, and had not been adulterated after importation. Samples F to J had been bought officially. TABLE A-SAMPLES OF COD-LIVER OIL, __ -___ OIL.Specific gravity, 15.5" 0. - Zeiss butyro-refractometer a t Zeiss butyro-refractometer a t Rotation (200 - millimetre tube) - - - - Hiibl, iodine per cent. - - KHO required per cent. for free acid - - - - KHO total per cent. - - Valenta test (" C.) - - Unsaponifiable matter per cent. - - - - FATTY ACIDS. Zeiss butyro-refractometcr a t 40" c. - - - - 25" C. - - - - 40" C. - - - - Korwegian. 168 0.1 18.7 95 - 57'0 162 0.1 18.5 95 - 56.7 C 0.928 79.7 70.3 167 0.2 18.7 96 1 '2 - 0.5" 56-7 Newfoundland. D - -I_ 0*928 79.0 70.3 - 0.5" 164 0-2 18'7 95 - 55.7 E 0.926 76'3 67.7 154 0'1 18'8 94 1-1 - 0.5" 53.7 F 0.927 79.0 70.0 - 0%" 160 0.2 18.7 95 - 56.3 Origin unknown. G 0.928 80.0 7 1 '0 - 0.7" 165 0 '1 18-6 96 - 57 -0 H 0,927 77-3 68.7 154 0'2 18.9 93 - 0'4" - 54.7 J 0.928 80'0 71-0 164 0 -1 18.6 94 - 0.6 - 56.7THE ANALYST.c -- 0.962, 87.3 f i * 7 - 0 5 ' 1 142 2.2 6.0 35 $4.0 - 211 I I tb E l 9 t i l g 0'91 160.3 Ir2'O - 0'1 69 0.5 20'2 86 0.9 3 i . i Table B gives the andyeis of the other oils. I n several cases the oils were Both shark and turbid when received, and were filtered clear before analysis. menhaden oils were dark brown in colour. WABLE B.-SANPLES OF FISH AND OTHEH. OILS, OIL. Specific gravity, 15'5'C. - - Zeiss biityro-rcfracto- nwter a t 25" C. - Zeiss butyro-re frac to- ineter a t 40" C. - Rotatioil (200 - milli- metre tube) - - Hiibl, iodine l)er cent. KHO recjuired per cent. for free acid - liHO total per cent. - Valeiitri test ( " C.) - UnsaponitiaLle nintter per c*ent.- - I.'.LTTY ACIIJS. Zeiss 1)utyro-refracto- meter a t 40' C. - - $ - 0'92 i2.7 34'0 0' 13'2 0.5 19'4 85 1.0 4 2 - i W - cd s 0'91; 65.0 56.0 - 1.0" 94 0'4 18.8 100 1 '0 43.3 0 9 1 ( 63.7 55.3 0" 84 0.3 19 '1 102 - 42 0'92' 58.0 59 *7 + 0.9 106 0.2 19'2 85 48 0.923 23.7 i0'0 0' 112 0'1 .9*6 90 - 46 Speczjic Gravity.-The British Pharmacopoeia gives the range of specific gravity as 0.920 to 0.930. My samples of cod-liver oil only varied from 0.926 to 0.928. Five of the foreign oils came within the official limits, menhaden and haddock were slightly heavier, shark was notably so (0.962)) while arrcchis, whale, hoi, and dugong were below 0-920. Refrcictiuns.-The samples were examined in a Zeiss butyro-refractometer at 45" C., and also at 40'. The sodium flame was used in each case to give a sharp reading.Seven of the cod-liver oils gave readings from 79 to 80; the other two were 76-3 and 77.3. The refractometer sharply distinguished most of the other oils, but menhaden (80.7) and brusmer (75) were very near to cod-liver oil. Readings were also taken at 40°, with the hope that the differences might vary with different oils. -4n alteration of lo C. in temperature produced a difference of 0.69 scale division with shark oil; all the other oils were included in the limits 0.55 to 0.62 scale division. May I here express the hope that workers with the refractometer will adopt one or two standard temperatures for their readings? Figures have been published at each 5' between 203 and 4 5 O . These variations make the comparison of published values unnecessarily difficult.I would saggest that butter and liquid oils should be * Filtered clc;ir lwfore analysis.212 THE ANALYST. observed at 25". The heating spiral cannot be used for a lower temperature than this all the year round, and when more heat is used the temperature of the instru- ment is not so constant. If the fat is not melted at 2 5 O , it may be examined at 40". These two temperatures would, I think, cover all practical purposes. Rotation.-Hoi was the only oil that had any marked effect on polarized light. I t gave a rotation of - 4" in a 20-centirnetre tube. Arachis was the only oil that gave a positive rotation (+0*9O). All the other oils are included in the limits 0" to -lo. Iodine Absorption.-In each case 25 C.C.of Hubl's iodine solution was added to about 0.25 gramme of oil and allowed to stand all night before titration. Some analyses of cod-liver oil have been published giving absorption values of about 140 per cent. of iodine. In these cases a shorter time has been probably taken, or a smaller excess of iodine used. Two samples of cod-liver oil absorbed 154 per cent. of iodine; the remaining seven from 160 to 168 per cent. Menhaden (174) and haddock (179) absorbed more iodine than cod-liver oil; the othsr oils required less, brusmer (138) being the nearest to cod-liver oil. Acidit?/ and Snpoiiificatioiz. Vnlzies.-These figures were obtained by adding 10 C.C. of ether and 5 C.C. of alcohol to about 5 grammes of oil, and titrating with seminormal alcoholic potash and phenolphthalein.When neutralized, 50 C.C. of alcoholic potash were added, and after saponification titrated back with seminormal hydrochloric acid. Shark oil contained most free acid, and required 2.2 per cent. of KHO to produce neutrality. The samples of cod-liver oil required 0.1 to 0.2 per cent., and the other oils 0.1 to 0.6 per cent., to neutralize the free acid present. The total saponification values of the cod-liver oils only varied from 1S.5 to 18.9 per cent. of KHO. Shark oil only required 6.0 per cent., of which more than one-third was due to free acid. Dugong oil required most KHO (20*2), while hoi was below the average with 16.9 per cent. of KHO. Yakntn Test.-The acetic acid used gave a figure of about 65' C . with butter. The nine samples of cod-liver oil gave resultsewhich only varied from 93" to 96". Another sample that had been in the laboratory eight years had a turbidity tempera- ture of 9.1".Cotton-seed oil (90") and whale oil (100") were the nearest values to cod-liver oil. Shark oil was the lowest (35"), and hoi the highest (113"). This is a useful test and one easily applied. Uitsaponi$able Mattcr.-Shark oil gave about 8.2 per cent., and five other oils about 1 per cent. As the quantities obtained in these five were very similar, and as emulsification gave considerable trouble, the amount of unsaponifiable matter was not determined in the other samples. Fatty Acids.-The refractometer readings do not apliear to be of any greater value thm those obtained directly on the oils, and probably the same remark would apply to their iodine absorptions.I attempted to obtain values for the titre of several of them, but fitiled to get constant readings.THE ANALYST. TAHLE C . - ~ E T Y L VALUES. 2 13 Soluble acid, per cent. KHO : Acetylated oil - - - Oil - _ - _ - Diff’erciice - - - ~ Saponification, per cent. KH3 : Acetylated oil - - - Oil - _ _ _ _ Difference - - - - Zeiss butyro-refractometer a t 25” : Acetylatecl oil - - - Cod-liver Oil. A 1 ‘4 0 2 1 ‘ 2 19-5 1 S . i 0.s 80.7 C 1 ’5 0 *3 1.2 1 9 . i 18.7 1.0 so -3 Seal. 1 . 7 0.4 1.3 20’5 19‘4 1.1 i 2 . i Haddock. 2‘4 0‘8 1-6 20 *6 19’3 1 -3 84 *i Ling. 1 -3 0.3 1 -0 19% 18’8 0‘8 74 *:I d c c t y l VaZues.-The determination of these is very tedious, and the results are useless for the detection of seal or ling oils, though it might be of some use for haddock oil.The refractions of the acetylated oils are also given, but the results are very similar to those obtained with the oils themselves. The British Pharmacopeia gives the following test : ‘ I A drop of sulphuric acid added to a few drops of the oil on a porcelain slab develops a violet coloration.” All the cod-liver oils except J gave a violet colour, as did also brusmer, hoi, and ling oils. The other oils gave more or less dark browns. By careful observation differences may be noted in the sequence of colours after adding H,SO,. They are best observed by watching a genuine oil side by side with one or two others. The colours change too rapidly to observe many samples at once. The three Norwegian oils, with F and G, gave a quick change of the violet colour into crimson, which finally became red-brown.The violet colour given by the Newfoundland oils turned to a, darker colour than that given by the Norwegian ones-purple rather than crimson. Hoi, ling, and brusmer oils gave a more intense violet than the Norwegian oils, but no crimson coIour followed. The British Pharmacopeia also requires that, “When nitric acid is carefully poured into some of the oil contained in a test-tube, a precipitate of coagulated albu- min should be formed at the surface of contact of the two liquids.” All the aamples of cod-liver oil except H and J gave a distinct white ring, though in some cases it was a long time in appearing. -Another of the British Pharmacopoeia ra,ctions is probably intended as a, test of quality rather than genuineness : “ No solid fat should separate on exposure of the oil for two hours to a temperature of 0” C.” Most of the oils complied with this test, the exceptions being as follows : Slight deposits were obtained with Newfoundland oil E, menhaden, hoi, and ling oils; while Xewfoundland D, dugong, whale, and arachis oils gave large deposits.Brusmer rapidly turned black. None of the other oils gave a white ring.214 THE ANALYST. One other colour-test was tried: Three drops of HNO, were added to about 12 drops of oil, and stirred at once. A11 the samples of cod-liver oil gave a fiery-red colour at once ; seal and dugong oils gave a pale-pink colour ; arachis gave no change ; sesame gave a pale green; and the other oils gave browns or yellows.The analytical work in the above communication was finished last October, and I intended making further experiments, but have not had an opportunity of doing SO. These results are therefore published as a contribution to the solution of a problem which the present high price of cod-liver oil makes somewhat important. DI~CU~SION. The PRESIDENT (Mr. Fairley) remarked that the author had made no reference to the question of age, which was of importance in regard to some of the points referred to, and particularly in regard to acidity. The 'fresh cod-liver oil, with regard to which some experiments were quoted, was, he presumed, last season's oil. Mr. BODMER said that recently there had been three successful prosecutions in Bermondsey for adulterated cod-liver oil.Twenty-six samples were examined at one time, and it had been found that the adulterated samples were sharply differentiated by the Zeiss butyro-refractometer from those which afterwards proved to be genuine-as far, of course, as it was possible to say, because he did not think it practicable to distinguish analytically between cod-liver oil and any other fish-liver oil, though a distinction could be made with certainty between an oil derived from the bodies of the fish and a fish-liver oil. In the case of the three adulterated samples in question, the refractometer readings at 25" C. (the temperature mentioned by the author) were respectively 73, 74.3, and 72. -4 specimen of undoubtedly genuine cod-liver oil gave a reading of 79, and Mr.Chattaway, who had kindly assisted him in the matter, considered 79 to 80 scale divisions to be about the limit for genuine oil. The colour tests used had been the British Pharinacopaeia test with sulphuric acid and Meyer's test with a mixture of two volumes of nitric acid and one volume of sulphuric acid. The latter test was an excellent one for the purpose, a magnificent salmon-pink colour being given when about 1 drop of the mixture was added to about 15 drops of genuine oil. The three samples in question gave no such colour, but only a dirty yellow, and the sulphuric acid test showed, not violet, but a brown colour. The other constants had been determined, but did not help much. The iodine values were respectively 135,138, and 123 ; but the published iodine values varied greatly, and it was difficult to get an average.Mr. Chattaway and Mr. Noor, however, who had worked a great deal at the subject, were of opinion that 140 was probably a good average. The saponification values (18.9, 18-47, and 18-62 per cent. KHO) were also of but little assistance. From the colour tests and from the low iodine values the presence of vegetable oils seemed possible, but none of the samples gave any cotton-seed or sesame oil reaction, and none of them gave any reaction with gold chloride. The last-named was supposed to be a test for arachis oil, and it was true that some samples of arachis oil were susceptible to reduction by gold chloride, but he did not think it could be regarded as a definite test. The three samples easily passed the British Pharmacopaeia freezing test, which simply meant that they would stand at freezing-point without any solid fat separating; but thatTHE ANALYST.215 was the case with a great many oils. Evidently, however, there was, practically speaking, no cod-liver+oil in any of the samples. From experiments made by Mr. Chattaway and himself, it eeemed that only a comparatively small proportion of real cod-liver oil was necessary in order to produce the violet colour in the British Pharmacopaeia test. The specific gravity limits were much too wide, and the other tests were of little value. The results of the albumin test, in particular, seemed to depend upon the conditions under which the oil had been expressed from the livers ; some genuine oils gave no albumin ring. Mr. BEVAN inquired whether Mr. Bodmer had applied the Maumenb test. Mr. BODMER said that, on account of the small quantity of oil (only about 2 ounces) at his disposal in each case, it had not been possible to include the Maumenb test. Mr. J. B. P. HARRISON said that he had recently examined an oil which coutained nearly 3 per cent. of unsaponifiable matter, and which appeared to be a mixture of cod-liver oil and shark oil. (AUTHOR’S NoTE.-hfost of the samples of oil were obtained in May and June last year, and with few exceptions the analytical figures determined in the same month.)

ISSN:0003-2654    

DOI:10.1039/AN9042900210

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

THE ANALYST. 215 ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. FOODS AND DRUGS ANALYSIS. The Amount of Sugar in Preserved Peas. F. Schwartz and F. Reichen. (Zeit. fiir Untersuch. der Nahr. und Genussmittel, 1904, vii., 550-553.)-The quantity of sugar contained in peas is known to vary to a great extent, small, undeveloped peas being considerably sweeter than riper ones. In examining four samples of tinned peas the writer found quantities of sugar (saccharose), varying from 2.69 to 30.48 per cent., calculated on the dry material. To prove that the larger quantity was not due to added sugar, he had a sample of peas preserved under his direct supervision. This sample showed 27.85 per cent. of seccharose on the dry peas. The method adopted consisted in extracting the broken peas with alcohol, evaporating the neutralized alcoholic extract, and repeatedly extracting the residue with alcohol and again evaporating.Finally, an aqueous solution free from dextrin waa obtained, which was treated with lead acetate and sodium phosphate, and polarized before and after inversion in the usual manner. w. P. s. Cider Vinegar and Suggested Standards of Purity. Albert E. Leach and Hermann C. Lythgoe. (Journ. Amer. Chent. SOC., xxvi., 375.)-The authors give the results obtained in the complete analysis of twenty-two samples of genuine cider216 THE ANALYST. vinegar derived from various sources. The usual methods of analysis were used. As malic acid is an essential constituent of cider vinegar, it &odd be identified. As standards the authors suggest that pure cider vinegar should contain at least 4.50 per cent.of acetic acid, and at least 2 per cent. of solid matter. The ash should be at least 6 per cent. of the solids. The alkalinity of 1 gramme ash should be equivalent to at least 65 C.C. TD acid. At least 50 per cent. of the phosphates should be soluble in water, The reducing sugars should be the same in amount after as before inversion, and should not exceed 85 per cent. of the solids. The specific rotatory power should be between -0.1" and -4.0" Ventzke when examined in a 200-millimetre tube. Malic acid should be looked for by both the lead acetate and calcium chloride tests. Most important for the recognition of adulterated samples are the determination of acidity, total solids, polarization, and the lead and calcium tests for malic acid.-4. G. L. Detection of Foreign Fats in Butter by Means of the Phytosterol Acetate Test. M. Siegfeld. (Zeit. fiir Unterszich. der hTdir. und Genzissmittcl, 1904, vii., 577- 585.)-The results of a number of experiments confirm previouestatements that this test will readily detect the presence of 10 per cent. of cocoanut oil or other vegetable oil in butter fat. Even smaller quantities than 10 per cent. give some indication, but the rising of the melting-point is not always evident. Phytosterol acetate prepared from various oils, such as rape oil, cottonseed oil, sesame oil, and cocoanut oil (ordinary and refined), gave melting-points between 128.3' and 132.5" C. after sis crystallizations. Cholesterol acetate, obtained from gall-stones, lard, blubber, and butter-fat, melted between 113.6" and 1154" after the fourth crystallization.w. P. s. The Detection of Cocoanut Oil in Lard. F. Morrschock. (Zed. fiir Untcrszich. der Nahr. und Genussmittel, 1904, vii., 586, 587.)-The test proposed depends on an examination of that portion of the fat which is soluble in alcohol. Eighty C.C. of the lard are heated with 160 C.C. of 95 per cent. alcohol to about 60" C. with frequent shaking. After completely cooling, the alcoholic portion is separated, the alcohol is distilled off, and the residue of fat analysed. Pure lard is only slightly soluble in alcohol. The soluble part has a considerably higher iodine value (about 70) than the original lard, the refraction is positive, whilst the saponifi- cation value remains unchanged.The addition of 10 per cent. of cocoa-nut oil to lard completely alters the composition of the portion soluble in alcohol. A lard containing this amount of cocoanut oil gave an iodine value of 54.65, a saponification value of 204.2, and had a refraction of - 1.9. The alcohol-soluble portion obtained from the mixture yielded an iodine value of 46-56, and a saponification value of 221.6, whilst the refraction was - 3.4. w. P. s. Determination of Tartaric Acid by Means of Zinc Acetate. H. Ley. (Pharm. Zeit., xlix., 149 ; through Phnrm. JOILI., 1904, lxxii., 681.)-As zinc tartrate is almost insoluble in water and quite insoluble in alcohol and acetic acid, the authorTHE ANALYST. 217 proposes to precipitate tartaric acid by means of zinc acetate, and to weigh the pre- cipitate after ignition as zinc oxide.X known weight of the acid is dissolved in a small quantity of warm water or alcohol and precipitated by the addition of an alcoholic solution of zinc acetate, One hundred C.C. of alcohol and 5 C.C. of 5 Fer cent. acetic acid are then added, and the mixture is left on the water-bath for some time. The precipitate is collected on a filter, washed with alcohol, dried, and ignited. The residue should be moistened with nitric acid and again ignited before weighing. Cream of tartar must be dissolved in boiling water and precipitated with aqueous zinc acetate solution before adding the alcohol. Crude argol should be dissolved in boiling water, treated with potassium carbonate (avoiding an excess of the latter), and then made up to a known volume.After settling, an aliquot part of the clear solution is taken for the determination. The method is applicable to wines if the tannin be first removed by treatment with animal charcoal. The presence of sugar does not interfere with the results. w. P. s. Does Pepper contain a Volatile Alkaloid? R. Kayser. ( z e d . fiir 6ffentZ. C,'licnA. 1904, x., 137, 138.)-The author has repeated Johnstone's experiments (.~NALYST, 1889, 41) and finds that pepper, on distillation with water, gives sn absolutely neutral distillate. The addition of magnesia to the distillation flask certainly caused an alkaline distillate to be obtained, but the alkalinity was proved to be due to ammonia. No piperidine was found at all.w. P. s. Detection of Bombay Mace in Banda Mace. W. Busse. (Zczt. f i i r Uiztorszxh. ile7 Xultr. z c n d Gmussmittcl, 1904, vii., 590, 591.)-The test described consists in pouring the alcoholic extract of the mace powder over strips of filter-paper, and then dipping the latter in hot barium hydroxide solution. Should as little as 2.5 per cent. of Bombay mace be present, the paper strips are coloured brick-red. With pure mace the upper part of the strip turns brownish-yellow, whilst the lower part changes to faint red. The strips retain their characteristic coloration for months, or even years (see also ANALYST, 1902, xxvii., 327). w. P. s. The Determination of Nitrogen in Food Materials and Physiological Products. H. C. Sherman, C. B. McLaughlin, and Emil Osterberg.(Jown. AIUW. Client. SOC., xxvi., 367.)-As the result of a number of determinations carried out with various modifications of the Kjeldahl method on different substances, the authors conclude that the transformation of the nitrogen into ammonium sulphate is seldom, if ever, complete until some time after the solution has become colourless or of a permanent faint straw colour. They recommend the following procedure : The sample is heated gent,ly with 20 C.C. concentrated sulphuric acid and 0.7 to 1 gramme of mercury until it ceases to froth; 10 to 15 grammes of potassium sulphate are then added, and the whole is boiled. Usually the liquid becomes colourless in less than thirty minutes, and the nitrogen is completdy converted218 THE ANALYST. within one hour, but occasionally two hours' boiling is necessary.unknown substances it is always safest to boil for the longer period. Apparently with A. G. L. Clove Oil. Thorn. (Pharm. Zeds., 1903, 781.)-A description of a new process for the determination of eugenol in clove oil : 5 grammes of the oil are heated on the water-bath with 20 C.C. of 15 per cent. soda for thirty minutes. The eugenol-soda eolution is run off and the separated hydrocarbons washed with dilute soda, adding the washings to the original soda solution. The reaction is effected on the water- bath with 6 grammes of benzoyl chloride. The crystalline mass is washed with water, and finally dissolved in 25 C.C. of hot 90 per cent. alcohol. This is cooled to 1 7 O , filtered and washed with alcohol until the total filtrate measures 25 c.c., the crystals are then dried at a temperature not exceeding 101", and weighed.As the solubility of benzoyl-eugenol in 25 C.C. of alcohol is 0.55 gramme, the following formula gives the total eugenol : a + 0.55 676- ' P=4,100 - when P=percentage, CL weight of benzoyl-eugenol, b weight of clove oil taken. H. A. T. Santalwood Oil. Parry and Bennet. (Ckmist and Druggist, 1904, i., 202.) -Figures obtained from a series of fractional distillations of genuine santalwood oil are given, showing that the pure oil or any fraction should have a refractive index not lower than 1.5030. The authors also show that the constants of the acetylated Oil are of value in the determination, and gives the following figures : Acctylated Oil from- 1.English oil ... ... ... 2. , 9 9 , ... ... ... 3. ,? 9 , ... ... ... 4. ... ... ... 5. Dui6h oii' ... ... ... 6. German oil ... ... ... Specific Gravity. 0-9860 0.9880 0.9870 0.9885 0.9875 0.9860 Rotation. ~~ - 14O30' 14'10 13O50' 14'0' 14'0' Hefractive Indes. 1-4916 1.4894 1.4899 1.4900 1.4915 1.4895 €3. A. T. Differentiation of Cassia Oil and Ceylon Cinnamon Oil. F. Billon. (Pliarnt. Zed., xlix., 1904, 107.)-Billon states that if a few drops of the oil to be examined are shaken with a little water, the emulsion filtered, and a few drops of a 1 per cent. solution of sodium or potassium arsenite are added, Ceylon cinnamon oil will give a greenish-yellow colour, but cassia oil will not. This test has been examined by Messrs. Schimmel,':' who find that exactly the reverse is the case-a greenish colour being only obtained with cassia oil. AS the * Sc?li?)n~reE's IL!,pt., 1904THE ANALYST. 219 colour is, at best, but faint, they prefer the usual ferric chloride reaction. This consists in adding a drop of ferric chloride solution to a solution, in alcohol, of the oil. Ceylon cinnamon oil gives a green, cassia oil a brown colour. A colour reaction for oil of cloves in cassia oil (Pool. Pharnc. Weekblad., XI., 1903, 1101) is Jacquemin's phenol reaction: 1 C.C. of dilute aniline solution is decomposed with sufficient sodium hypochlorite solution to produce a violet colour. A drop of the oil is added, shaken, diluted with water, and filtered. With pure cassia, oil a violet filtrate is obtained ; if oil of cloves be present the filtrate has a, dark-green colour. H. A. T.

ISSN:0003-2654    

DOI:10.1039/AN9042900215

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

THE ANALYST. 219 ORGANIC ANALYSIS. Lintner's Soluble Starch, and the Estimation of Diast atic Power. John 9. Ford. (Journ. SOC. Chern. I?zd., April 30, 1904.)-In this paper the author describes experiments bearing out his opinion that the reason for the increase in the diastatic activity of malts, occasioned by the addition of small quantities of acids, asparagine, etc., is to be found in their neutralizing properties for any alkaline im- purities present in the solution. Very minute traces of such impurities have a strong inhibitory effect on diastatic action. Experiments made in order to verify the values given by Brown, Morris, and Millar, for the copper-reducing power of maltose are described, the results of which confirm those of these workers. Attention is called to the difficulty of obtaining a definite hydrate of maltose, and the author recommends air-drying at 90".The soluble starch used was the ordinary Lintner's preparation, and stress is laid on the importance of washing this until it is eutirely free from acid, as even when the washings are neutral the starch itself may still give an acid reaction. The presence of a greater or less proportion of amylo-dextrin in the starch, occasioned by excessive or insufficient treatment with acid, is not of importance in this connection. Experiments with hydrochloric and lactic acids showed that increasing quantities of acid increased diastatic action until the neutral point is reached, when the action slowly decreases. The effect of small additions of NaOH was prejudicial to diastatic action, but only very slightly so in the case of a starch containing much acid phos- phates.This is ascribed to the formation of NaBHPO1, which undergoes extremely slight hydrolysis, so that the addition of sufficient NaOH to bring about the forma- tion of some Na,PO, is necessary, This breaks up into NaOH + Na,HPO,, only then rendering the solution appreciably alkaline. inverting power " of such a starch is practically nil, it can scarcely be described as of an acid character. The inhibitory effect of asparagine is very slight at and below 40". At higher temperatures asparagine increases the diastatic activity, but to nothing like the extent mentioned by Mohr. With starches free from alkaline impurities there is no indication of increased activity. Very small traces of copper are highly prejudicial to diastatic action, mercurial As the220 THE: ANALYST.salts even more so. Asparagine, in some incomprehensible manner, overcomes the retarding effect of copper salts. Kjeldahl states that borax has a strong retarding action, this is evidently due to the alkaline nature of this salt. Potassium cyanide, which has been suggested and used as an antiseptic in this connection, has a considerable inhibitory effect. The author finds, contrary to accepted theories, that all starches, however pre- pared, and from whatever source, give perfectly concordant results under comparable conditions. He suggests that nitrogenous and mineral matters in the starch might influence diastatic action; and it is also pointed out that, though the malt solution may be neutral, when this is mixed with the starch solution entirely new conditions will prevail, dependent on the altered concentration and the impurities present in the starch.The strength of the starch solution (within the limits of “ Kjeldahi’s Law of Proportionality ”) has some slight effect, action being greater with stronger solutions ; but this is, in practice, negligible. The solubility of glass vessels is also of importance; Jena glass only should be used. I t appears, therefore, that, though the purity of the starch is the main factor, the diastatic power of malt is influenced by many apparently trivial details; and as there is a tendency during manipulation to alkaline contamination, a starch prepara- tion containing a small amount of acid phosphates is preferable for analytical purposes.The author comes to the following conclusions : 1. That traces of impurities have an important influence. 2. Diastatic (amylolytic) action attains its maximum in neutral solution, in the 3. ,bparagine and other substances said to accelerate diastatic action do SO only 4. The restricting effect; of acids depends on their dissociation. (The greater 5. Purified starches, of various origins, give equal maltose productions with sense that water is neutral. when there has been a previous restriction. the amount of free hydrogen ions, the greater the restriction.) equal amounts of diastase. H. A. T. Use of Sodium Peroxide in the Analysis of. Organic Substances. Hans H. Pringsheim. (Amer. Cliem. Journ., xxxi., 386.) -Halogens in solid organic substances are determined by burning the substance with sodium peroxide in a, loosely-covered crucible as previously described (vide ANALYST, this vol., p- 97).Instead of reducing any halogen acids lormed by pouring the filtered solution of the melt into sulphurous acid solution, however, the author now recommends adding 5 C.C. of a strong solution of sodium sulphite to the filtrate, and then acidifying with sulphuric acid, the object being to keep the volume as small as possible. Liquid substances are burnt in a crucible provided with a lid which may be screwed on andTHE ANALYST. 221 made tight by a copper washer. A capillary glass tube is cemented into a hole in the lid; a copper-wire ending in a loop is sealed into the glass tube, and to this is fastened a piece of thin iron wire which reaches to the bottom of the crucible, and can be made red-hot by passing an electric current through the crucible and copper wire.The liquid substance to be analysed is poured from a weighing tube on to a layer of sodium peroxide spread on the bottom of the crucible, which is then loosely filled with a mixture of sodium peroxide with the twenty-fifth part of its weight of a carbohydrate. Phosphorus and arsenic may be determined similarly, using a silver crucible, and employing half as much sodium peroxide again as is necessary for a halogen determination. The results quoted are good. A. G. I;. The results obtained are excellent. The Determination of the Iodine Absorption by Oil of Turpentine.T. F. Harvey. (Journ. SOC. Chem. ITLd., April 30, 1904.)-The author finds that the amount of iodine absorbed from Wijs' solution by oil of turpentine is largely governed by : (1) The time of contact ; (2) excess of Wijs' solution ; (3) excess of halogen over that required for the formation of IC1; (4) hydration of the acetic acid. Experiments were made with three solutions : S'dutiou A.-\Vijs' solution, with slight excess of iodine (25 C.C. = 49 C.C. :G thio- Sohtion B.-Solution A, with slight excess of chlorine (25 C.C. = 51 C.C. q , thio- Sdz~tion C.-Solution A, with large excess of chlorine (25 C.C. = 6 H C.C. ;& thio- The turpentines used were : .L-A fraction of American turpentine distilling at 155" to 156". 3.-A sample of American turpentine. sulphate).sulphate). sulphate) This was diluted to about s. TABLE I. Tzirpcntirlc FrnctaoiL ( A ) . Solution A4 : Excess halogen = 42 per cent. : Trace of water present ... ... + 18 C.C. of water ... ... ..* Trace of water present ... ... + 13 C.C. of water ... ... ... Trace of water present ... . . . Solution B: Excess halogen = 40 per cent. : Solution C: Excess halogen=32 per cent. : Five Minutes. 203.7 204.4 227.5 223.4 238.2 One Hour. 206 -0 205.3 228.9 226.8 Three Hoius. a05 -5 207.6 229.1 229.0 253.6222 Solution A. THE ANALYST. Solution U. TABLE 11. American Turpentinr, (B). Excess Halogen, Per Cent. of Total added. 26 30 34 40 40 40 53 81 Time of Standing. 1 hour ,, *, 5 minutes 1 hour 3 hours 1 hour ) * ~~~~ 131-7 151.3 172.6 215.3 215.1, 214.0 213.9 332.7 409-0 - - - 225.4 225.4 224 a 7 348.3 - The author is of opinion that dilution with water occasions substitution of the acetic acid.This view is borne out by the fact that, when some substance such as carbon tetrachloride (in which substitution cannot occur) is used, no variation is noticed on dilution wibh water. H. A. T. Turpentine Oil. Herzfeld. (Zeds. f. 5f. ChmG., ix., 1903, 454.)-A\ process proposed by Herzfeld consists in allowing 10 C.C. of the turpentine oil to drop slowly into 40 C.C. of concentrated sulphuric acid. After ten to twelve hours 8 to 9 per cent. of the oil separates. The lower dark-brown layer is drained off, and the remaining oil is shaken with 3 C.C. or 4 C.C. of fuming sulphuric acid. After standing for several hours a further 1 to 2 per cent.of the oil separates. Any mineral oil present will proportionately increase the volume of this separation. H. A. T. Cinnamic Aldehyde. Hanue. (Zeit. Uyzters. Nuhr. Gen. Mittel, vi., 1903, 817.) -€bums proposes an exact method for the quantitative estimation of cinnamic aldehyde based on the separation of this substance as semi-oxamazone. 0.2 gramme of cinnamon oil is added to 85 C.C. of water, and finely divided by shaking. Of semi-oxamazide (14 times the quantity of the oil), 0.3 gramme, dissolved in hot water, is added, shaken for five minutes, then left to stand for twenty- four hours with occasional shaking. The separated semi-oxamazone is filtered on a tared Gooch tile, washed with cold water, and dried at 105'. The following formula gives the percentage of cinnamic aldehyde : a .60.83. when : CL = cinnamic-aldehyde-semi-oxamazone found 9 S s = quantity of oil used. give results correct to within about 1 per cent. This method has been checked in Messrs. Schimmel's laboratories,':' and found to They recommend dissolving the oil * Schimncl's &rpt., 1904,THE ANALYST. 223 in 10 C.C. of 95 to 96 per cent. alcohol before adding the water, thus obtaining the oil in such a finely divided condition that the aqueous solution is merely opalescent. In the case of Ceylon cinnamon oil Hanus's method was not so satisfactory as the more readily applied bisulphite process, probably owing to the presence of other aldehydes. This method has a further special value, facilitating the ready estimation of the aldehyde content of cinnamon bark, and is applied as follows : 5 to 8 grammes of the finely ground bark are brought into a large Erlenmeyer flask with 100 C.C.of water, and, after heating to boiling, a current of steam is passed in the manner usual in steam distilling. The condensed distillate is repeatedly extracted with ether, dried, and treated as above described. Hanus's method has also been tested by Messrs. Schimmel as to its applicability to the determination of citral, citronellsl, menthone and carvone, aldehydes and ketones generally, but has been found quite unsatisfactory. H. A. T. Ethereal Oila. Schimmel and Co's Report. (Through Clicrn. Zeit., xxxi., 1904.)--Ayopinol Oil.-According to Kaimazu (Journ. Phariu. SOC. Jap., 258, 1903), this oil contains formaldehyde, pinene, and a new terpene-alcohol-apopinol, CI,H,,O.The author suggests that the presence of the aldehyde may serve as a simple method of differentiating between this oil and camphor oil. The presence of other less important terpenes is suspected. Bay Oil.-A sample of leaves from Bermuda furnished an oil differing widely from common bay oil. This oil, of which 1.33 per cent. was obtained from the leaves, has an optical rotation = - 3" 4', specific gravity = 1.0301, refractive index = 1.53012, and contains 61 per cent. of phenols. I t is soluble in 0.4 volume of 80 per cent. alcohol, the dilute solution being opalescent. Particularly noticeable are the high specific gravity and the ready solubility of this oil. Cypress Oil.-In addition to the already determined d.camphene and cypress camphor in cypress oil, closer examination has proved the presence of furfural, d. camphene, d. sylvestrene, cymene, sabinol (?), terpene-alcohol, esters (of acetic and valeric acids), and a ketone with a smell suggesting those of both menthone and thujone, and which was isolated as a semi-carbazone melting sharply at 17'7" to 178". Pimento Oil.-The following constituents have been determined : cineol, phel- landrene, caryophyllene, met hyl-eugenol, eugenol, and palmitic acid. The presence of small quantities of terpene-alcohols is probable, but has not been proved. NEW ETHEREAL OILS : Kuromaji OiL.---I sample of this pale yellow, almcst colourless, eJapanese oil had a specific gravity = 0.8947 ; optical rotation = - 14" 39' ; ester number=29*87.From its odour, similar to that of coriander (oil ?), it is probable that it also contains linalol. Cnlytraittlias panicidat~i," and known as may oil, was received from Porto Rico. I t resembles lemongrass oil, has It is soluble in 0.9 volume of 80 per cent. alcohol. May Oil.--tl sample of an oil distilled from224 THE ANALYST. a specific gravity = 0.9509, optical rotation = - 1” 52’. I t is very readily soluble in 80 per cent. alcohol, imperfectly so in 70 per cent. alcohol. I t contains 62.5 per cent. of citral. Oil of “ Media Citruta.”-This plant is known locally (Florida) as bergamot- mint, and about 0.2 per cent. of the oil can be procured from the young non-flowering plants. Of a pale yellow colour, it has an odour resembling rather that of lavender oil than that of bergamot. Specific gravity = 0.8826 ; optical rotation = - 5” 35’ ; eater number = 31.28 (equal to 10.95 per cent.of linalyl acetate). Soluble in 2 volumes of 70 per cent. alcohol. Oil of “ LTylitis Spicata.”-This plant (Florida) furnishes only some 0.005 per cent. of a pale yellow oil. Odour slightly resembles that of mint. Specific gravity= 0.915 ; optical rotation = - 27” 25‘ ; acid number = 2-17 ; ester number = 4.35. I t is insoluble in 10 volumes of 80 per cent. alcohol. The odour apparently indicates small quantities of menthone or pulegone. Oil of “ Ambrosia Arteiuisicefoliu ” (Florida). - The young plants furnished 0.15 per cent. of a green oil having an agreeable odour. Specific gravity=0*876; optical rotation = - 1”; ester number = 7.94.Phis oil dissolves in an equal quantity of 90 per cent. alcohol to a clear solution, becoming turbid on addition of further alcohol. Oil of ‘‘ l3uptoriuirL Ca~ill~oZium.”-About 1 per cent, of a pale yellow oil can be distilled from the flowering herb. Specific gravity = 0.926 ; optical rotation = + 18’ 38’ ; ester number = 7-11. I t contains much phellandrene, and forms a turbid solution in 3.5 volumes of 90 per cent. alcohol. A!ll the eucalyptus oils contained much lineol and no phellandrene. They are soluble in 1 to 1.5 volumes of 80 per cent. alcohol. Oil of 6 L Eucalyptus Nicrocorys ” has a specific gravity = 0.9038 ; optical rota- tion = + 120 29’. OiZ of L 6 23. Piiiictata ” has a specific gravity = 0.9060 ; optical rotation = + 4” 10’. This oil contained a small quantity of cumin-aldehyde. Oil of “ E.liesiuifera ” has a specific gravity = 0.9123 ; optical rotation = + 6” 1’. Essence d e Bmg;,re.-This Australian oil is of a pale greenish-blue colour (traces of copper), and has an agreeable aromatic odour. Specific gravity = 0.8587 ; optical rotation = + 2” 44’. Oil of “ Ergtfu-oxylou M0120y~112~172.”-2.56 per cent. of oil can be distilled from the wood. It forms a, sticky, crystalline mass, with an odour similar to that of guajah-wood oil. Specific gravity = below 1 ; acid number = 6.77 ; ester number = 1-56 ; melting-point = 42” to 45” ; ester number after acetylation = 131. I t forms a slightly turbid solution in 1 volume of 90 per cent. alcohol, which clarifies on the addition of further alcohol. H.A. T. Several Soiith :Iitstraliau Eiicalyptus ant1 liiijcpict oils are mentioned. Spike Oil. Parry and Bennet. (Chemist and Druggist, 1903, 702.)-In order to better detect adulteration of this oil, the authors propose to reduce the strengthTHE ANALYST. 225 of the alcohol used for testing from 70 per cent. to 65 per cent. Seventy per cent. alcohol will dissolve samples which are grossly adulterated, while the pure oil dissolves in six volumes of 65 per cent. alcohol at 15". This solubility is much altered by the addition of most adulterants. H. A. T. Schimmel's Test for Citronella Oils. (Schinzmel and CO.'s Report, April-May, 1904,)-Owing to complaints from Ceylon as to the difficulty of maintaining a constant temperdture of 20° during this test, it is pointed out that, though 20" should not be exceeded, the temperature may fluctuate within a few degrees below this point, and the use of an ordinary refrigerator is recommended.If the test be properly applied, a possible separation of the oil should take place almost imme- diately, and prolonged observation is unnecessary. K. Bamber (Proc. Chcm. SOC., xix., 1903,292) suggests a new method for judging citronella oils which is as follows: A mixture of 2 C.C. of the oil with 2 C.C. of a pure cocoanut oil, free from acids, is shaken with 20 C.C. of 83 per cent. alcohol in a graduated tube, and centrifuged for half to one minute. 15" With a pure citronella oil the cocoanut oil is said to separate quantitatively. Should an insoluble adulterant be present there must be a corresponding increase in the volume of the cocoanut oil, and the actual percentage of this would be obtaiiiable by multiplying the increase by fifty.Messrs. Schiinmel have examined this process, and find that, while excellent as a qualitative test, it is useless from a quantitative point of view. Results are given showing that, owing to the more or less ready solubility of the adulterant, and the large factor of error lying in the difficulty of determining with accuracy the increase of volume in the cocoanut oil, this method is, quantitatively, unreliable. Nessrs. Schimmel's experience is that the best test for such an oil is to deter- mine its solubility in 80 per cent. alcohol, then again after adding 5 per cent. of Russian petroleum. If genuine, the oil should have approximately the same degree of solubility in both cases, though the opalescence would be greater.No separation should take place. This rests on the fact that the fairly readily soluble Russian petroleum may be undetectable to the extent of, perhaps, 10 per cent. Vith a pure oil, therefore, the 3 per cent. added does not influence the test, while, should such petroleum be already present, the added quantity is sufficient to materially affect the solubility. H. A. T. Essential Oils of Gouft and Scheih. P. Jeancard and C. Satie. (Bull. sot. C'hint., 1904, xxsi., 478-480.)-Thesa oils were obtained by distillation of the entire plants, which grow in the higher parts of Algeria. Oil of Gozi-ft.-This was light yellow, had an odour of absinthe, and gave the following analytical results : Specific gravity at 9.5" C., 0.8720 ; rotatory power at 10" C., 15-90 ; specific viscosity at 9.5" C., 49 ; acidity, 1.12 ; saponification value, 14 ; saponification value after acetylation, 43.I t was soluble in half its volume of 96 per226 THE ANALYST. cent. alcohol. I t began to distil at 155" C., and 75 per cent. passed over below 170" C. It was found to consist mainly of Lpinene, whilst an alcohol with the odour of geraniol was identified in the fractions distilling above 170' C. Oil of Scheih.-This was a reddish-brown oil with a terebenthine odour, recalling that of lentiscus. It gave the following results : Specific gravity at 9.5" C., 0.9540 ; specific viscosity at 9.5" C., 170; acidity, 8-4; sapoDification value, 66.5; and saponifica- tion value after acetylation, 129.5.It wae soluble in 1 part of 80 per cent. alcohol, and 2.5 parts of '70 per cent. alcohol at 12" C. I t contained about 15 per cent. of phenols dissolving in sodium hydroxide solution. The distillation of the oil freed from phenols began at 175" C., 48 per cent. of the oil passing over above 200" C. C . A. M. A New Adulterant of Patchouli Oil. W. H. Simmons. (Chemist and Druggist, 1904, xliv., 815.)-The usual adulterants, cedarwood and cubeb oils, seem to have lately been supplemented or replaced by an ester or ester-containing oil. Two samples of patchouli oil analysed by the author gave the following figures : A. Specific gravity 150 c. ... ... ... 0.9948 15" C. Rotation [:ID ... ... ... ... - 38" 30' Acidity ..... ... ... ... trace Saponification number ... ... ... 58 Refractive index at 20" C. ... ... 1.5175 Solubility in 90 per cent. alcohol ... 1 in 0.75 With the exception of the saponification number, these figures do from those yielded by genuine patchouli oil. The unsaponifiable oil when separated, acidified, and distilled, gave a distinct quantity 13. 0.9937 1.5110 trace 18.5 1 in 0.5 not diff'er widely in the sample A, of benzoic acid, - 49" 30' togetherwith a small amount of volatile fatty acid, whilst B gave some volatile fatty acid but no benzoic acid. The sample A was evidently adulterated; but the small quantity of saponifiable matter in I3 may have been due to defective distillation or the use of leaves contaminated with foreign matter. w. P. s. On a Method for the Evaluation of Caoutchouc.A New Method for the Analysis of Caoutchouc. (Gzinzmi-Zed., 1904, xviii., 461, 339, 521 ; through Clzem. Zeit. Rep., xxviii., 96.)-The author does not think the method of Schneider (Chem. Zeit., xxviii., 173), in which the chloroform solution of the caout- chouc is precipitated with alcohol, applicable to unknown samples of caoutchouc. For a sample of Uganda rubber, in which he found 32 per cent. of oxygen, the method gave 92 per cent. of a-caoutchouc. He also states Guayule caoutchouc to belong to the oxygen-containing class of rubbers. I n analysing rubber, according to the author's nitrogen dioxide method, the extracted caoutchouc should be finally dried in a current of coal-gas. The normal C. 0: Weber.THE ANALYST.227 addition product is only obtained if (L rapid stream of dry nitrogen dioxide is used. In most cases it is necessary, before filtering the acetone solution of the addition product, to whirl it in a centrifugal machine. A. G. L. The Detection of Thiocyanic Acid in Saliva. E. Pollacci. (A?i?z. de Chim. iwuZ., 1904, ix., 162.)-From 10 to 12 drops of saliva are mixed with a little mercurous chloride, black deposit of mercury being formed in a few minutes when thiocyanic acid is present- The test is confirmed by the red coloration produced on adding a dilute solution of ferric chloride to the supernatant liquid. Other acid secretions of the body also reduce calomel in the same way. Hg2C1, + SKCNS = Hg + Hg(CNS), + 2KC1. C. -4. M. TOXl COLOGl CAL ANALYSIS. On the Behaviour of Certain Organic Compounds towards Blood, with Special Regard t o the Identification of Blood. Oscar Adler and Rudolf Adler. (Zeit. physwl. Chem., 1904, xli., 59 ; through Chenz. Zeit. Rep., xxviii., 109.)-The authors have examined the behaviour towards blood of a number of organic compounds which give a colour reaction on oxidation. I n general the higher members of any one series of bodies appear to give the most delicate reaction. To detect blood-stains leucomalachite green seems to be most suitable; the stain is thoroughly moistened with the reagent, and then treated with a 3 per cent. solution of hydrogen peroxide. To detect the presence of blood in water, leuconialachite green, the leuco base of crystal violet, or benzidine, may be used. To the water in question a little hydrogen peroxide and acetic acid are added; if a few C.C. of benzidine solution are then run in, the liquid will be coloured an intense green if blood was present. This reaction takes place even if the water has been boiled. By means of it 1 part of blood in 100,000 parts of water may be recognieed. Leucomalachite green and benzidine may also be used for the detection of blood in urine, a procedure similar to that of Weber’s modification of the guaiacol test being employed. A blood-stain will become an intense green colour. A. G. L.

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THE ANALYST. 227 INORGANIC ANALYSIS. A Method for the Direct Determination of Alumina. C. E. Rueger. ( h g . and Mining Journ., lxxvii., 357 ; through Chcm. Zeit. Rep., xxviii., 94.)-The hydrox. ides of iron and aluminium, obtained as usual, are dissolved in hydrochloric acid. After exactly neutralizing the liquid with sodium hydroxide 10 grammes of solid sodium sulphite are added, and the whole is stirred until the salt is dissolved. If no precipitate ia obtained, more sulphite must be added. Hydrochloric acid is then added until the precipitate has disappeared, and the liquid is boiled until the sulphur228 THE ANALYST. dioxide is completely expelled, which requires about ten minutes' boiling. The pre- cipitate is then filtered off and washed with hot water ; if it contains any iron the separation is repeated.In any case, it will contain any titanium and phosphorus present. The presence of zinc, manganese, and nickel is said to be without influence on the determination. The results obtained with this method are within 0.3 per cent. of the theoretical when 1 gramme of substance is taken for the analysis. A. G. L. The Iodometric Determination of Iron in the Ferrio State. R. Namiae (Mon. Scientif., 1904, xviii., 254, 255.)-The method based on the and I;. Carcano. reaction does not always give exact results, owing to the readiness with which the reverse reaction takes place- 2Fe2C1, + 2HC1+ 1, = Fe,CI, + 2HI. The authors have found that the method may be rendered accurate by removing the free iodine with a solvent, preferably chloroform. The solution containing the iron salt oxidized by nitric acid is evaporated to dryness with an excesa of hydrochloric acid, and the residue dissolved in the smallest possible quantity of the same acid.The solution is diluted so as to contain 1 to 2 per cent. of iron, nearly neutralized with sodium carbonate, and treated with hydrochloric acid until the proportion of acid reaches 5 to 10 per cent. The potassium iodide and 5 to 10 C.C. of chloroform are then added, and the closed flask allowed to stand for twelve hours with occasional shaking, after which the free iodine is titrated with standard thiosulphate solution. A blank test is also made with the same proportions of hydrochloric acid, chloroform, and iodide, and the amount of iodine found deducted from that previously obtained.Fe2CI, + 2KI = 2FeC1, +I2 + 2KCl C. A. M. The Determination of Pruesian Blue. C. CofElgnier. (Bull. s'oc. Chim., 1904, xxxi., 391-396.)-The method is based upon the fact that Prussian blue is soluble in a mixture of equal parts of hydrochloric acid and an alcohol of the ethylic series, preferably propyl alcohol. Two grammes of the commercial blue preparation are treated with 100 C.C. of the eolvent, and the liquid made up to 200 C.C. as soon as all the blue has dissolved. The solution is filtered from the base (barium sulphate, kaolin, alumina, etc.), and 100 C.C. of the filtrate are treated with. water. The precipitated blue is washed by decantation with water and propyl alcohol until free from acid, then collecbed on a weighed filter, dried at 100' C., and weighed.When a large proportion of alumina is present in the preparation the blue only dissolves with great difficdty in the solvent, even after prolonged boiling ; but solution takes place readily when the base is kaolin, barium sulphate, starch, etc. The amount of water required for the precipitation varies with the concentration of the solution. Thus, to completely precipitate the blue from 50 C.C. of a 0.1 per cent. solution, 79 C.C. of water are required, as against '20.5 C.C. for & 0.5 per cent. solution, and 8 C.C. for a 1 per cent. solution.THE ANALYST. 229 The followiDg resalts obtained with mixtures of kaolin, calcium carbonate, alumina, etc., containing known quantities of Prussian blue illustrate the accuracy of the method, Blue introduced ...... 70.0 60.0 50.0 27.5 15.0 12.5 7.5 3.0 Blue found ... ... ... 69.8 60.3 50-2 27.4 14.8 12.3 7.4 2.7 Per Cent. C. A. M. The Gas-Volumetric and Gravimetric Determination of Copper. E. Riegler. (Zeit. anal. Chem., 1904, xliii., 212-214.)--Gas-Volumetric Method.-The reaotions and method are analogous to those used in the determination of calcium (following abstract). The copper is precipitated as copper iodate, which is washed with 95 per cent. alcohol and made to react with hydrazine sulphate. The volume of nitrogen liberated calculated into milligrammes and multiplied by the factor 0.755 gives the amount of copper in milligrammes. Gravimetric Method.-The solution of the copper salh (about 15 c.c.) is treated with pure iodic acid in the proportion of eight to ten times more than is necessary for complete precipitation, and hested to the boiling-point with constant agitation.It is then withdrawn from the flame, and, after the addition of 25 C.C. of 95 per cent. alcohol, is well shaken and allowed to stand for two hours. The precipi- tated copper iodate is collected on a weighed washed filter, with 95 per cent. alcohol until free from acid, dried for twenty-four hours in a desiccator over aulphuric acid, and weighed. The weight of the salt multiplied by the factor 0.1474 gives the corre- sponding amount of copper in grammes. The experimental results quoted agree closely with the theoretical amounts. c. A. M. The Gas-Volumetric Determination of Calcium, Barium, Strontium, and Potassium.E. Riegler. (Zeit. aml. Clzem., 1904, xliii., 205-212.)-These determinu- tions are further applications of the gaa-volumetric methods devised by the author (AXALYST, xxviii., 157), and are carried out in the same way. Calcium-The method is based on the formation of calcium iodate, which is only slightly soluble in water and insoluble in alcohol- CaCl, + 2HIO, = Ca(IO,), + 2HC1- and on the reaction between calcium iodate and hydrazine sulphate- Ca(IO,), + 3N,H,. H,S04 = CaSO, + 2H2S0, + SHI + 6H20 + 3N,. Each milligramme of nitrogen liberated is equivalent to 0.664 milligramme of calcium oxide. Barium and Strontium.-The principle of the method is the same as in the case of calcium. One milligramme of nitrogen corresponds to 1.821 milligramrnes of barium oxide and 1.23 milligrammes of strontium oxide.The amounts of barium or strontium oxides in the solutions analysed should not exceed 0.180 gramme and 1.20 grammes respectively. Potassi?bm.-The following reactions form the basis of this method : (1) &PtCl, + 6HI0, = 2KH2(I03), + H,PtCI,.230 THE ANALYST. The tri-iodate (which is insoluble in dilute alcohol) reacts with hydrazine sulphate thus- One milligramme of nitrogen liberated is equivalent to 1*922 milligrammes of potassium platinochloride or 0-3726 milligramme of potassium oxide. (2) 2KH,(I0,)3+9N2H4.H2S04=K2S0,+8H,S0, +6HI+9N2. C. A. M. A New Method of Fractionating Ceric Earths. H. Lacombe. ( B d . Soc. Chim., 1904, xxxi., 570-573.)-Demarvay’s method (Comptes Rend., cxxx., 1019) of separating ceric earths from yttrium earths by fractional crystallization of their double magnesium nitrates in concentrated nitric acid is not satisfactory in the case of the components of the old didymium.The author has, therefore, attempted to find a salt with a smaller solubility than the double alkali nitrates and a greater solubility than the double magnesium nitrates, and has obtained the best results with the double manganese nitrates corresponding to the type 2Di(N03), + 3Mn(N03), + 24H,O. These double nitrates are best fractionated in nitric acid of specific gravity 1.3, and the amount of mother liquor ought always to be kept fairly constant, and in a small proportion with regard to the crystals. The slight decomposition of man- ganese nitrate that occurs during the concentrations is obviated by adding & few drops of fuming nitric acid to clear the solution.Supersaturation is prevented by introducing a crystal of the double nitrate of bismuth and manganese, a salt isomor- phic with those of the rare earths. The author has tested this method on earths rich in neodymium and praseodymium with very satisfactory results, as was also the case with earths containing much lanthanum and very little didymium. Samarium was separated much more rapidly and completely than by Demarqay’s method. C. .4. M. Determination of Sodium Perchlorate in Commercial Sodium Nitrate. H. Lemahre. (Monit. Scient., 1904, 4th Series, xviii., i., 253; through Chem. Xeit. liep., xxviii., 108.)-The method consists in reducing the perchlorate with sodium sulphite to chloride, and determining the latter.For a nitrate containing less than 4 per cent. of sodium perchlorate, 5 grarnmes of the nitrate and 3 grammes of dry sodium sulphite are gently heated to quiet fusion in a platinum crucible. The melt is dissolved in water, the solution heated to boiling, and 200 C.C. of boiling 4 per cent. barium nitrate solution are added. The precipitate is filtered off, 8.2 C.C. of normal sodium hydroxide and 1.2 grammes of sodium persulphate are added to the filtrate, which is then heated to boiling and again filtered. After exactly neutralizing the filtrate with acetic acid, using phenolphthalein as indicator, the chloride is titrated with silver nitrate solution. A. G. L. Sprengel’s Method for Colorimetric Determination of Nitrates. Launcelot W.Andrewe. (Jozwn. .4mr. Chem. SOC., xxvi., 388.)-The author found that the d o u r of paranitrophenol and of its sulphonic acid in aqueous solution is discharged by acidifying the liquid with a minimum quantity of hydrochloric or sulphuric acid,THE ANALYST. 231 whilst the colour of di- and trinitrophenol is not destroyed. If an acidified solution of either of these nitrophenols is shaken with benzene, the nitrophenols dissolve in it ; on shaking the benzene with potassium hydroxide, a yellow colour is imparted to the latter. Ortho- and paranitrophenolsulphonic acidp, on the other hand, do not diesolve in the benzene. Applying these tests to Sprengel's method, the author shows that the yellow substance obtained is not picric acid, as commonly supposed, nor dinitrophenol, according to Ifontenari, but a mononitrophenolsulphonic acid. As a standard solution for use in the test, he suggests a solution of 0.993 gramme paranitrophenol in 1 litre of water, each C.C.of which is equivalent to 0-1 milli- gramme of nitrogen. A. G. L. On the Use of Antipyrin in Analysis (Nitrite Reaction). C. Reichard. ( C h c m Zeit., xxviii., 339.)--l'or the identification of nitrites by means of antipyrin (ScJitiytcn, Clicvz. Zeit., ss., l i Z S ) , 10 C.C. of a very dilute (0.1 per cent.) solution of the nitrite should be used. The acetic acid solution of the antipyrin is added drop by drop, so as to avoid any large excess, which may cause colouring matters to separate from the solution. The reaction is sharp enough to identify 1 part of nitrite in 20,000 parts of water, but does not appear to be well suited for quantitative purposes, a8 the colour produced tends to change and fade.A. G. L. On the Maercker-Buhring Saiution. Otto Foerster. (C'hcm. hit., sxviii., 147.)-Since the ammoniurii citrate-timgnesia mixture used for phosphate analyecs certainly takes up silica on prolonged standing in glass vessels, the author recom- mends that, unless so much of the eolution is used that it is very frequently renewed, not only should the ammonium citrate mid magnesia solutions be stored separately, but the former solution should only be made up from citric acid and ammonia in small quantities at a time as required, as it is especially the ammonium citrate which has a solvent action on glass. A. G. L. The Sensitiveness of the Sodiuy Nitroprusside Reaction for Sulphides. C. Reichard. (Zeit. niud. Chenc., 1904, xliii., 222-230.)-A saturated solution of sodium nitroprusside is capable of detecting 0.000018 gramme of hydrogen sulphide in the form of gas or as ammonium or an alkali sulphide, the reaction increasing in intensity with the concentration of the solutions. Sodium hydroxide interferes with the reaction, and ammonia should be used when it is wished to combine the hydrogen sulphide with a base. C. A. 31.

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DOI:10.1039/AN9042900227

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年代:1904

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THE ANALYST. 231 APPARATUS. Determination of the Turbidity and Depth of Colour of Solutions by Means of the Diaphanometer. ( Z e d fiir Untersuch. tier A'nlir. und Gcnussmittcl, 1904, vii., 587-59O.)-Furcher experiments with this instruiiient (this vol., p. 136) show that very t d i l or strongly coloured solutions apparently J. Konig and B. Kruss.232 THE ANALYST. allow proportionately more light to pass through them than do dilute solutions. This is explained by the f a d that faintly turbid solutions behave more like clear solutions, whilst those which are very opaque resemble an opal or milk-glees plate. The latter, while transmitting little light, is illuminated -by reflected light on its surface. As, how6ver, in quantitative determinations by the instrument comparison solutions are used, the results are not affected w. P. s. A Kjeldahl Apparatus. M. Siegfried. (Zed. physkl. Chem., xli., 1 ; through Chew. Zeit. Rep., xxviii., 94.)-To avoid bumping during the digestion with sulphuric acid, especially when large quantities of inorganic substances are present, the author uBes an apparatus by which the flask is kept in continual motion. The apparatus may be obtained from R. Rothe, of Leipsic. *A. G. L.

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DOI:10.1039/AN9042900231

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年代:1904

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232 THE ANALYST. REVIEWS. THE VEGETABLE ALKALOIDS. By Dr. A d PICTET translated and enlarged by H. C. BIDDLE Ph.D. (New York John Wiley and Sona. London Chapman and Hall Ltd. 1904. Price 21s. net.) STUDENTS IN MEDICINE. By Dr. E. SALKOWSKI authorized translation by W. R. ORNDORFF A.B. Ph.D. (New York John Wiley and Sons. London : Chapman and Hall Ltd l.904. Price 10s. 6d. net.) JACKSON Ph.D. (New York John Wiley and Sons. Hall Ltd. 1904. A LABORATORY MANUAL OF PHY8IOLOGICAL AND PATHOLOGICAL CHEMISTRY FOR DIRECTIONS FOE LABORATORY WORK I N PHYSIOLOGICAL CHEMISTRY. By HOLMES c. London Chapman and The first of these volumes is a translation of Dr. Am& Pictet’s well-known work on the constitution of the vegetable alkaloids with important additions relative to the relations of the caffeine group of alkaloits to the purine bases the synthesis of nicotine atropine etc.the constitution of the jaborandi alkaloids and other matters. The book forms a handsome volume well furnished with referenoes to original memoirs. Dr. Biddle appears to have done his work well and the authoritative work of Professor Pictet needs no commendation from us. The volume under review will be an indispensable addition to the library of every English worker on the vegetable alkaloids. Dr. Orndorfl’s translation of Dr. E. Salkowski’s “Practicum d. Physiol. u. Path. Chemie,” a book of high authority cannot fail to be welcome to all workers in pathological laboratories. Dr. Jackson’s book is intended as a text-book for advanced medical students to whom it will be valuable when supplemented by the aid of an instructor to solve the numerous queries put by the book to the student. Price 5s. 6d. net.) It is however in no sense a treatise on analysis. Alnalytical processes are well described. T. S

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DOI:10.1039/AN9042900232

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年代:1904

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