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Proceedings of the Chemical Society, Vol. 12, No. 172 |
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Proceedings of the Chemical Society, London,
Volume 12,
Issue 172,
1896,
Page 241-252
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摘要:
PROCEEDINGS OF THE CHEMICAL SOCIETY. EDlTED BY THE SECRETARIES. -~ __ ___ No. 172. Session 1896-9 7, Dee. litli, 1996. Mr. A. G. Vernon Harcourt, President, in the Chaitir. Messrs. Alexander Scott, Frederick B. Power, W. W. Cobb, and Claude M. Thompson were formally admitted Fellows of the Society. Certificates were read for the first time in favour of Messrs. Alfred Cartmell, Alexandra Road, Burton-on-Trent ; William Diamond, Pge Bridge, Alfretcn ; William Buckland Edwards, 5, Gnrlinge Rmd, Brondesbnry, N.W. ; Vaughan Harley, M.D., 25, Harley Sheet, W. ; Fred Ibbotson, R.Sc., 9, Melbourn Road, Spring Vale, Sheffield ; David Smiles .Jerdan, MA., B.Sc., 68, Union Street? Greenock ; Edward Rosling, Itelbourne, Chelmsford ; Henry Pottw Stevenp, B.A., 14, Lower Sloane Street, Chelsea, S.W.; Harry Thompson, Wdton House, West Parade, hnlaby Road, Hull. The certificate of the following candidate, recommended by the Council, under Bye-law I, psi-. 3, was also rend:-Jyoti Bhusan Bhaduri, Presidency College, Calcutta. Of the foll~wingpapers those marked * were read. *165.“On the experimental methods employed in the examination of the products of starch-hydrolysis by diastase.” By Horace T. Brown, F.R.S.,G. Harris Morris,Ph.D., and J, H. Millar. The paper is divided into the following sections : (1) thc deter- miriatioil of solids from solution-density ; (2) determination OE specific rotatory power; (3) the relation of [a], to [a]D ; (4) de-termination of cupric reducing power; (5) limits of accuracy of the methods, 242 The authors state that this acconiit is a preface to a series of papers dealing with the qucstion of st,?rch-liyrlrol~si~,and is a,critical review of the experimental methods which have been employed by different observers who have approached this subject. An attempt has ako been made to remove the misundei=standing which still exists as to the relations of the different systems of notation.The deterniination of the total solids from the density of the soln- tion by the employment of the “divisor” method admits of great accuracy if the solution-densities of the pure substance have been previously determined. The ‘;divisors ’’ at varying concentration have been determined for cane siigar, maltose, dextrose, le viilose, soluble starch, and the mixed products of starch-hydrolysis of various grades, snd the results hare been plotted out in the form of curyes whose equation is given in each case.The pure substances used in constructing these curves were dried in a vacuu~iiover phosphoric pcntoxidc at tcmperntures from 100’ to 130’. For mixed st:trch Iriydrolytic products, the divisor for equal concen- trations increases with the spccific rotatory powf?r, and in such a regulnr manner that when the valne of R is known, the divisor at any given concentration can be calculated. From the relation which this divisor bears to the divisor of the apparent maltose present in the mixed hydrolytic products, it is deducible that the divisor for the arayliti constituent is constant for equal concentrations, even in starch products of vei-y different grades of hydrolysis.In the section on specific rotatory power, the methods of exact determination are discussed, and the relations of [a]J, [CL]~~.~~,and [a]D are defined for substances of equal dispersive power. As the dispersive power of cane sugar is sensibly different from that of dextrose and starch-hydrolytic products obtained by diastase, the factors for the conversion of [aJJinto [a]=are not identical in these cases. Much confusion of these relations has also been introduced by the unrecognised fact that [%IJ has been referred to two distinct rays in the yellow of different refrangibility. The cupric-reduction of maltose and of the products of starch-transformation is constant only when the conditions of experiment are identical.These are exactly defined for the authors’ method of procedure, and the reducing values are given in tabular form, and are compared with those of other obsei%vers. “166. ((On the specific rotation of maltose and of soluble starch.” ByHorace T. Brown, F.R.S.,G. Harris Morris, Ph.D., and J. H.Millar. The authors’ determinations of the specific rotatory power of maltose at a temperature of 15.5” do not confirm the statement of 243 Meissl that tlie values of [cc], vary with the concet~trat~ions between 2 and 20 per cent., but confirm the geuernl statement of Ost that between these limits the specific rotatory power is constant.At higher concentrations than 20 per cent.., the specific rotatory power diminishes slightly. The actual results point to a vduc of [aID= 137.93", which is sensibly greater than Ost's value OE 13i.46' at 15.5". This discrepancy is dlie to the fact that Ost cniployed weighed quantities of hydrated maltose which Lad been dried in a desiccator over sulphuric acid. The authors find that cven after six weeks' drying in this manner, hydrated maltose contains 0.46 per cent. more water than corresponds to C,2H22011*H20.If Ost's numbers are corrected for this they give values, up to 20 per cent. concentrationF, of [aID= 138.12' at 15..5", a result. almost exactly ideutical with that of the authors. The specific rotatory power of solubIe starch for concentrations of 2.5 to 4.5 per cent.is, at 1-5.5", [a]== 202.0'. *167."On the relation of the specific rotatory and cnpric-reducing powers of the products of starch-hydrolysis by diRstase." ByHorace T. Brown, F.R.S.,G. Harris Morris, Pb.D., and J. H. Millar. Whcn starcli is transformed by diastase, a certain relation is altvaj s ~OLII~LIsubsist bctwcen tEc cnpric-rednct,ion and specific rotatory to powcr of thc hydrolytic products. This relation can be expressed in such a manner as to be entirely independent of any view me may hold as to the true niiture of tae transformation prodacts, and it is of so cxact a nature that if one property is known the other can be prc-dicted with certainty. This is true not only for the niixed hydro- lytic products, but for any fractionated portion of them.The authors regard this fact as lying at the root of the whole question of starch-li5.drolSsis, and, as it is still not admitted by most. coiitincii'cal workers, they bring forward a large amount of fresh evi- dence wliidi they regard as absolutely conclusive. The results of tlic emmination OE 70 dil'ferent starch transforma- tions are givcn, sonie of thcm mixed products, otbws fi-actionated products, the spccific rotatory and cupic-reducing poxers being given in the various notations in use. When the experimental results are plotted on a system of rectangular co-ordinates, the degrees of specific rotation between soluble starch acd maltose being represented on the line of ordinates, and the cupric-reducing powers from soluble starch to maltose on the line of abscissq t,he values all fall practically on a straight liiic joining t'lie points of intersection of the co-ordinates correspouding to the optical and reducing properties OF solnble starch and of maltosc rcspcctivcly.244 The properties of soluble starch being R = 0, [aIu = 202”, and of maltose, R = 100 and [a]D = 138*0°,then the relation of specitic rotation and cupric reduction for any mixture or fractionation of the starch-hydrolytic products will be expressed by [a]D = 202 -0.64 R. The differences in the calculated aod observed values for the 70 cases of hydrolysis examined are given, and are shown to be very small indeed. The authors have examined the published results of C.J. Lintner and of Ost, both of wbom have denied the existence of any relation between [&ID and R,, and find that, when rightly interpreted, they, for the most part, strictly conform to the law of relation expressed above. DISCUSSIOX. Dr. ARMSTRONG,after commenting on the value of the information brought under the notice of the Society by MY.Horace Brown and his co-workers, and on the remarkable accuracy with which starch could now be estimated, expressed the hope that it would be possible ere long to determine what really took place when starch was hydro- lysed ; he thought it was time that we should no longer be content merely to determine certain analytical factors ; we onghf rather to seek for chemical methods which would render it possible to separate and isolate the products.Mr. A. R. LINGasked what value the authors found for the cupric reducing power of maltose when Wein’s method was used. Dr. 0. H. MORRIS,in reply, said that they found that Wein’s tables give results about 5 per cent. too low when the cupric reduction of maltose is estimated by Wein’s method, arid the copper obtained calculated into maltose by the table ; in other words, perfectly pure maltose gives R = 95-96 instead of 100. ”168.“The action of hydrogen peroxide and other oxidising agents on cobaltous salts in presence of alkali bicarbonates.” By R..G. Durrant, M.A. Similar green solutions may be obtained by adding hydrogen per-oxide, sodium h~pochlorite, chlorine, bromine, or ozoiie to cobaltous salts in presence of alkali bicarbonates-or by adding a cobaltous salt to the anode of previously electrolysed potassium carbonate.The green colour is not destroyed by excess of cold acetic acid, but is rendered rabher bluer in tint. This acetic solution is reduced by hydrogen peroxide. The evidence so far obtained shows (1) that the cobalt is in the “cobaltic state.” This is proved by the results of three 245 volumetric methods-in which standard sodium hypochlorite, hydrogen peroxide, and sodium sulphite are respectively employed-green precipitates, produced from the green solutions, gave results showing that the available oxygen closely approximates to that to be expected from cobaltic hydrate.(2) That the green colour of the solutions and of the precipitates appears not to be due to a particular alkali, since (i) identical tints were obtained with the five different alkali bicai-bonates, (ii) potassio-cobaltic nitrite gives no green colour with bicarb- onates, (iii) green precipitates washed free from all alkali, and digested with cold weak acetic acid give green filtrates. (3) That carbon dioxide is necessary both for the formation and preservatioir of the green colour. The green colour of the acetic solution remains only so long as carboir dioxide is present. The green precipitates (free from alkali) retain carbon dioxide so long as they remain green, and lose it when they become brown. It is, therefore, possible that the green cobaltic compound is of the nature of a carbonate.DISCUSSIox. Several speakers, iiiclucling the PRESIDENT,expressed the view that whilst the author had made it clear that the green substance was a cobaltic compound, further proof was needed of the suggestion that the salt formed was a cobaltic carbonate. Dr. RIDEALmentioned that sodium peroxide, as well as hydrogen peroxide, gave rise to the green colour, provided that an alkali bicarbontate was also present. Dr. ARMSTRONGsaid that he would like to give expression to the opinion that the time was come to determine what should be their course of action with regard to the publication of the discussions that took place at the meetings; of late there had been an almost entire absence from the Proceedings of reports of the remarks made in the room, although these had oEten been of a nature which made it desirable that they should be brought under the iiohice of the Fellows generally.If the Secretaries could not undertake the work, steps should be taken to procure a proper report. Personally he had had no ditliculty in obtaining reports during the nine years in which he had charge of the Proceedings, and he did not believe that there would be any difficulty. Without such reports the Proceedings were of little value. Professor DUNSTANsaid that Fellows attending the meetings were aware that it was not often that it comprehensive discussion followed 246 the reading of an ordinary paper. All important remarks and sag-gestioris made at the meekings had been recorded in the Proceedings, and although no attempt,liad been made to record everything, and there might occasionally be room for difference of opinion RS to what was impcrtaiit, he was alKays glad to receive from speakers, after the meeting, reports of their remarkp, which he believed had been in nearly every case inserted in the Procerdings.He had, howevey, not thought it desirable to print Dr. Armstrong’s remsrks, of tihe omis- sion of which Dr. Armstrong now complained, made on two recent occasions proposing to record the time occupied by readers of papers. The method adopted by the speaker’s predecessor in office in report- ing discussions had given rise to much dissatisfaction.If the present plan was not thought sufficient, then a shorthand report of the dis- cussions could be taken. As a matter of fact, howeyer, the main yalne of the Proceedings lies in its being the means of bringing at an early date under the notice of the FelloKs, not merely remarks and suggestions made at the meetings, but concise abstracts of the papers read, the full publication of which could not take place in the Journal until much later. The PRESZDENTremarked that if a, full report of the proceedings were considered desirable, its preparation could not be incladed in the duties of the Honorary Secretarie2. He was disposed to think, however, that if it %ere generally known that the Secretaries were ieady to ieceive from speakers after the meeting a few sentences giving the substance of their remarks, that this would meet, the case in nearly every instance.‘I169. Electrical conductivi!y of diethylammonium chloride in aqueocs alcohol.” By James Walker, Ph.D., D.Se., and F. J. Hambly, F.I.C. The authors have determined the conductivity of diethylammouium chloride dissolved in pure water, and in 10.1,30.7, 49.2, 72.0,90.3, and 99.0 per cent. alcohol, by volume, at dilutions ranging from 10 litres to 8000 litres. Tables and curves have been constructed, show- ing the variation of the molecular conductivity and the degree of dissociation with ynrying dilution and varying proportions of alcohol. 170. “ Formation of substituted oxytriazoles frcm phenylsemicarb-azide.” By G eorge Young, Ph.D., and Henry Annable. The action which takes place when a mixture of phenylsemicarb-azide and benzaldehpde is oxidised, bas been reinrestigrtted, and the views expressed by one of the authors in a previous paper (Trans., 1895, 67,1063) have been confirmed.The following aldehydes yield 247 oxytriazoIes by this action : metanitrobenzaldehyde, paranitrobenz- aldehyde, metatoluic aldehyde, terephthalic aldehyde, cinnamic alde- hyde. The authors have failed to ohtain oxytriazoles from formaldehyde, acetaldehyde, paraldehyde, isobutyric aldehyde. 171. ‘‘ a-Bromocamphorsulpholactone.” By C. Revis and F. Stmley Kipping, Ph.D., D.Sc. When a-bromocamphor is heated with anhydrosulphuric acid, or with clilorosulphonic acid, it is converted into a-bromocarnphor-sulphonic acid (Trans., 1893, 63,548).In the course of some experi-ments on the preparation of this sulphonic acid, it was found that when 70 per cent. anhydrosulphuric acid is added to a solution of a-bromocamphor in chloroform, t,he product consists, to some extent, of a crystalline compound which is ir,soluble in water. This substance has the composition CloH,,BrS04(found C = 3S%, H = 4.3,Br = 25.1, S = 9.7 per cent. ; calculated C: = 39.0, H = 4.2, Br = 25.8, S = 10.3 per cent.). It appears to be a bromo-camphorsulpholactone, and its formation is doubtless due to the oxida- tion of hydrogen to hydroxyl accompanying sulphonation, water being then eliminated fyom the hydroxysulphonic acid ; it is, probably, closely related to the dibromvcamphorsulpholactone, C10H12Br2S01, recently described (Lapworth and Kipping, Proc., 1896, 12, 77), and if resembles the latter in ordinary properties.It crystallises from chloroforni and ethylic acetate in lustrous, ti-ansparent plates or prisms, melts at about 290°, and is moderately easily soluble in boiling acetic acid, chloroform, and ethylic acetate. It is very stable, and separates, unchanged, from a solution in nitric acid (sp. gr. 1*4), even after heating for some time ; it seems not to be attacked by cold potash (sp. gr. 1*3)?and, even on boiling, it is only slowly dissolved. Dr. Lapworth has, independently, observed the formation of this lactone from a-bromocamphor and anhydrosulphuric acid.172. (I Dimetliylketohexamethylene.” By F. Stanley Kipping, Ph.D., D.Sc. In a recent paper on camphoric acid (Anzer. Chem. J.,1896, 18,685), Noyes describes the preparation, from dihydrocampholytic acid, oE it ketone which forms an oxime melting at 112-113’, and possesses an odour similar to that of camphoroxime. On comparing the melting point of this oxime with that of the isomeric oxime of dimethyl-ketohexamethylene, he found that, for the latter, the author had given the melting point 114-115’ (Trans., 1895, 67, 349), whereas Zelinsky had given it as 104-105” (Ser., 1895, 28,781). Noyes 248 himself then prepared dimethylketohexamethylene oxime, and found the melting point to be 120-122'. The possible identity of the two osimes in question being a matter of great importance-for, if their identity were established, much light would be tliroyn on the constitution of camphor-the author bas prepared dimethylketohexamethylene by the impyoved method recently described (Kipping and Edwards, PYOC.,1896, 12, 18S), and has made further experiments with this substance.The oxime, prepared in the usual manner, is at first very oily, apparently from the presence of unchanged ketone, bat; it soon becomes a semi-solid crystalline mass ; when freed from oil and recrystallised once or twice, it melts quite sharply at about 114', but further purification raises the melting point to 117.5' (uncorr.), at which point it remains, even after six successive crys- tallisations from different solvents.This melting point and that previously recorded were taken with an ordinai*y standard thermo- meter ; observations made with a short thermometer, the thread of which was entirely immersed, gave B m. p. of 118*3--119'. Noyes does not state whether the m. p., 180--122O, is corrected, nor how the observation was made, and the range of 2' would seem t3 indicate that t'he substance did not melt sharply; he also leaves the identity of his dimethylketohexamethylene oxime with the oxime of the ketone which he obtained from camphor an opeii question. Noyes mggests that the several preparations of the oxime obtained respectively by Zelinsky, by himself, and by the author, may be inix-t,ures of stereoisomerides, and the latter has therefore directed atten- tion to this possibility ; there are certainly indications of the presence of more tlhan one substance in the crude oxime, as a few crystals, melting not sharply at about 75", have been separated ; never-theless, the only crystalline product which has yet been isolated in any quantity is that which melts bharply and constantly at, 118.5-119O (corr.) .This oxime crystallises from a mixture of chloroforni and light petroleum in lustrous, transparent prisms, wliich have been examined by Mr, Pope. " The crystals consist of monosymrrietric prisms, which show the forms (loo), (OOl), (110), and (111) ; the plane of sym-metry is the optic axial plane, and an optic axis emerges normally to Che face (100). Some faces give good reflections, but parallel faces do not give images at 180' to one mother, a behaviour which is fre-quently observed in the case of mixtures." This indication that the oxime may be a mixture, iit spite of its constant melting point, must be borne in mind, and if confirmed, the different melting points of the various preparations would be accounted for.In order to facilitate the identification of dimethylketohexarnetliyL 249 cne, the author has prepared the sernicarbazone ; this coinpound slowly separates in crystals on warming the ketone with a solution of semicarbazone hydrochloride and sodium acetate in dilutc alcohol. After recrystallisation it melts at about 196O, aiid fnr ttlicr treatment does not seem to change its meltisg point. A sample dried at 1G0" gave C = 59.26, H = 9-36 per cent.; calculated for C,H,,N,O, C = 59.02, H = 9-29 per cent. Dimethjlketohexamethylene semicarbazone is fairly soluble in cold chloroform but less so in cold benzene and etliylic acetate, and crys-tallises best from methyl alcohol in the form of small, tmnslncent, well-defined prisms. Heated slowly from about 175", and using a short thermometer, it begins to sinter at about 190°, and melts com- pletely at about 200-20l0, effervescing, but not darkening; the m. p. depends 011 the size of the crystals and on the rate of heating. The crudc semicarbazone seemed to be homogeneous, and the yicld appeared to be good, but as, on recrystallising the preparation froni boiling acetic acid, most of it suffered decomposition, further experi- ments are necesary to prove that only me semicarbazone exists.173. lr The localisation of deliquescence in chloral hydrate crystals." By William Jackson Pope. Chloral hydrate crystallises from solution in large monosymmetric platcs, showing the forms (loo), {Oll], and (ill),and haring the axial ratios n : b : c = 1.6369 : 1 : 1.3951, = 59' 5' ; these crystals consist of the same modification of chloral hydrate as was obtained in previous experiments (Pope, Proc., 1896,12,142), and described as the biaxial modification, stable at ordinary temperatures. The crystals deliquesce in the air, but in a peculiar manner ; the forms (011) and { 111)rapidly absorb water vapour, and after a few minutes' exposure become covered with a layer of solution, whilst the faces of the form (100) remain perfectly bright during a, considerable time.The attraction for moisture exercised by the pinaco'id (100) is thus much less than that exhibited by the other two forms. It is consequcnttly concluded that crystal deliquescence, like crystal solubility and other properties, varies with the direction in thc crystal perpendicular to which its intensity is measured. 174. " Enantiomorphisrn .'' By William Jackson Pope and Frederic Stanley Kipping. Crystals of the tm7o enantiomorphous forms of a substance which exhibits circular polarisation only in the crystalline state, and it] which the circular pola,risation is an inherent property of the crystal structure, i.e., of a subst,ance belonging to Class 2b (Popc, Trans., 250 1896,69,971),should be deposited from the optically inactive solution in eqnal numbers, unless any disturbing factor is operative favouring the deposition of crystals of one particular enantiomorphoas form, as, for example, contact of the slightly supersaturated soluticn with a crystal of that form.The truth of this statement can be demonstrated from our present knowledge of crystal structure, and is also evident from a coiisideration of the recent work of Lmdolt (Ber., 1896, 29, 2404), who showed that the crystalline powder of sodium chlorate, which rapidly separates from aqueous solu tion, consists of almost equal quantities of dextro- and hvo-rotatory crystals.Tiis authors have extended these obscrvstions, and bp taking a number of dif-Terentcrops of the large crystals dcpositcd l~y spontancous evaporation of sodium chlorate solution, have ascertained that the average numbers of dextro- and Izvo-crystals deposited are the same, in absence of any disturbing factor. It seemed probable that if a substance which is optically active in solution is introduced int]o an aqueous solntion of sodium chlorate, the presence of the former would favour the deposition of chlorate crystals of one particular enantiomorph, and experiments were consc- cluentiy made to test this view. About 5 per cent. of some substance, suc:Ii as dextrose, mnnnitol, and isodulcitol, w;is dissolved in a s:LtuYiited sodium chlorntc solution, and the crystals of the salt depositcd 011 spon taneous evaporation exanlined ; rz great prepondei*cmccof 1zx:vo-crystals separated from the dextrose solutions whilst in tho sopai.a-tion from the isodulcitol solutions the dextro-crystals were in excess.The mannitol solutions deposited rather more 1~-o-than dextro- crystals ; a, number of crops from each solution were collected, and similar behaviour was noticed with each crop. This selective deposition would seem to indicate, as would, indeed, bc expected, from a consideration of the equilibria possible in such systems, that tlie solubility of a dcxtYo-cnan~iouiorp~iof Class 22, (scc above) in a liquid containing an opt icnlly active substance, differs from the solubility of tlic I~vo-ciiiLntionior~~hin thc same solveiif,. SolGbility cfe tcrrtiinn?ions, aiicl nlso clet ci-niim~tioiisof the rates of growth of dexti.6- and ~mvo-ci*gstals of sodium di1oratc in optically active solutions are in progress.There would seem to be no ti p?"L'orireason why a substance optically active in solution only and possessing a high specific rota- tion, should exert more directive iiifluence on tlie deposition of crystals of Class 2b than an optically active siibstance of very low specific rnta- tion, the only condition necessarily favouring the deposition of crystals of a particular enantiomorpli being that there should be an asynl- metric compound in solution. Using methods such as thow indicated above, it might, therefore, be possible to d :tcrmitie with czs;: rapid- ity m hether certain substances which, although containing asymmetric carbon atoms, 2i-e optically inactive in solution, are really asymmetric compounds, the inactivity in solution being due to a compeusation brought about amongst the four different groups attached to one asjmmetric atoni.Experiments respecting this point are in pro-gress. Several cases, such as ttmt of carnphorsnlphonic chloride (Kipping and Pope, Trans., 1893,63,560),are known in which equal quantities of optical antipodes, when crystallised together, apparently do not form a racemic compound. In the light of the foregoing results, it should be possible to effect a partial sepamtion of such mixtures, and even of racemic compounds, by crjstallisiug them from a solution con- tainiiig an optically active substance.Experiments on the separation of a number of racemic compounds, and of iriactive mixtures of optical antipodes by met8hods based on the above considerations, have been commenced, but the results are not yet sufficieiitly con- clusive to warrant my definite statements respecting them. Premising the truth of the considerations stated sborc, Eakle’s obserration (Zeit.f.Kryst., 1896, 26, 562) that a sodium periodntc solution containing sodium nitrate deposits more lcevo- than dextro- ci*ystalsof the periodate, is quite incomprehensible. IMPORTANT NOTICE TO AUTHORS OF PAPERS. The attention of authors is directed to the following resolution of the Council.“NO title shall be included in the list of titles of papcrs to bc honglit before a Meetiug of the Society, unless the paper and an abstract of it are in the hands of the Secretaries at least three days hefoi~the date of the Meeting ; and no announcement of titles can ho made in the Proceedings until the papers have been rcceivcd by the Secretaries.” RESEARCH FUND. A meeting of the Research Fund Committee mill be held in January. Applications for grants, accompanied by full particulars, should be sent to the Secretaries,on January 15. 252 At t’lienext meeting, on January 21st, the following papers will be received. The authors of those marked with an asterisk hare announced their intention of being present :-*“ Slitdies of the properties of highly purified substances.I. The influence of moisture on the production of ozone from oxygen and on the stability of ozone. IT. The behaviour of chlorine, bro-mine, and iodine with mercury. 111. The hchtiviour of chlorine under the influence of the silent discharge of electricity, and in sun-light.” By W. A. Shenstone. *“Action of diastase on starch.’’ Part 111. By A. It. Ling and J. TA Baker. *“ The solation-density and cupric reducing power of dextrose, levulose, and invert-sugar. By Horace T.Brown, F.R.S., G. Hariais Morris, Ph.D., and J. H. 3MIar. “ Derivahives of M:wlurin.” Part, TI. BJ-A. G. Pcrkin. RAHILISON AND SONS,PRJNTERS IN ORDINARY TO HER M.+JESTY, ST.MARTIN’S CAPE,
ISSN:0369-8718
DOI:10.1039/PL8961200241
出版商:RSC
年代:1896
数据来源: RSC
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