摘要:

AbstractA new variation theory based on the behavior of function vector in a dual vector space is presented. The procedure is applicable to any quantum mechanical eigenvalue‐eigenvector problem and gives appropriate solution even with crude numerical integration to save computational cost. The theory offers an absolute measure of propriety for the assigned trial function. Applications on a free particle with a definite momentum, a particle in a one‐dimensional box with a definite energy, the one‐dimensional harmonic oscillator, and the ground state of helium atom are shown to demonstrate the merits of the t

ISSN:0009-4536    

DOI:10.1002/jccs.198200001

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractAn emission spectrographic method for the quantitative determination of 17 trace elements in high‐purity lanthanum oxide has been developed. The sample was ignited in muffle furnace at 850° for onehourto remove the moisture and carbon dioxide, then blended with equal amount of graphite and 10mgsof this mixture was taken into electrodes. A 10 amps dc are was employed to excite the mixture and a 3.4 meter Ebert Spectrograph with 15,000 LPI plane grating was used to record the spectrum in the region 2,200 at 3,400 Å. The weak line of lanthanum was used as an internal standard. The working ranges of these elements were: Ag, Mg 0.5 to 50ppm; Be 0.5 to 100ppm; V, Cr 1 to 100ppm; Cu, Sn, Fe 3 to 100ppm; Ge, Mn, Ni 5 to 100ppm; B, Co, Pb, Sb 10 to 100ppm; Ca and Si 30 to 500ppm. The precisions fell in the range of 10 to 24%.Samples obtained from Engineering Research Laboratory (ERL) of Institute of Nuclear Energy Research were also exami

ISSN:0009-4536    

DOI:10.1002/jccs.198200002

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe partition of Fe(II) between hydrochloric acid solution and solvent ofdi‐(2‐ethylhexyl)‐phosphoric acid (HDEHP) in kerosene has been studied at varying concentrations of hydrochloric acid, solvent and Fe(II) ion. A stoichiometric extraction equation was derived as:Fe2+(a)+2(HX)2(0)=FeH2X4(0)+2H+(a)where the subscriptsaandorefer, respectively, to aqueous and organic phases. Corresponding to the stoichiometries, value ofKswhich equaled was obtained from the plot of D[H+]2vs. F2where D is the observed distribution ratio, F the concentration of HDEHP in organic phase. The kinetic studies of the extraction of Fe(II) species from hydrochloric acid into HDEHP under nitrogen atmosphere was carried out and the forward and back reaction constant was calculated. Also the oxidizing effect of air on the HDEHP‐Fe(II) complex in organic phase was

ISSN:0009-4536    

DOI:10.1002/jccs.198200003

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractA convenient synthesis for varions (Z)‐1‐alkanesulfinyl‐2‐phenylethenes has been developed. This involves addition of different sodium thiolates to phenylacetylene in ethanol, and oxidation of the resulting (Z)‐1‐alkanesulfenyl‐2‐phenylethenes [(Z)‐styryl alkyl thioethers] with sodium metaperiodate supported on acidic alumina. The corresponding sulfones can be obtained by oxidation of these (Z)‐styryl alkyl thioethers with hydrogen peroxide in glycial acetic acid, or, alternatively by reduction of the β‐iodostyrylsulfones with zinc in acetic acid. These β‐iodostyrylsulfones were obtained by addition of the corresponding sulfonyl iodides to phenylacetylene under the catalytic action of cupric chloride and

ISSN:0009-4536    

DOI:10.1002/jccs.198200004

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractIn continuing search of the structure‐activity relationship of heterocyclic chromones, 4‐quinolyl and 3‐quinolyl moieties were each introduced to the C‐2 position of chromones. A total of 12 quinolyl chromones were synthesized. 4‐Quinolinecarboxaldehyde was condensed with 2‐hydroxyacetophenones to provide the chalcones. These intermediates were then subjected to selenium dioxide dehydrogenation to yield the 6 new 4‐quinolyl chromones. 3‐Quinolinecarboxaldehyde was condensed with 2‐hydroxyacetophenones in the presence of dilute alkali to give aldol compounds of chalcones (dehydration products of aldols). Ring cyclization of the chalcones yielded the other 6 new 3

ISSN:0009-4536    

DOI:10.1002/jccs.198200005

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractMethyl palmitate (I), methyl stearate (II), stigmasterol (III), β‐sitosterol (IV), (O‐acyl)‐β‐D‐glucopyranosyl‐(1→3)‐stigmasterol (V), (O‐acyl)‐β‐D‐glucopyranosyl‐(1→3)‐β‐sitosterol (VI), β‐D‐glucopyranosyl‐(1→3)‐stigmasterol (VII), β‐D‐glucopyranosyl‐(1→3)‐β‐sitosterol (VIII), β‐D‐ecdysone (IX), diosgenin‐3‐α‐L‐rhamopyranosyl‐(1→2)‐[α‐L‐arabinofuranosyl‐(1→4)]‐β‐D‐glucopyranoside (X), diosgenin‐3‐O‐β‐chacotrioside (dioscin) (XI), and diosgenin‐3‐O‐α‐L‐rhamnopyranosyl‐(1→4)‐α‐L‐rhamnopyranosyl‐(1→4)‐[α

ISSN:0009-4536    

DOI:10.1002/jccs.198200006

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractA simple method for the proximate determination of triterpene glycosides in glycyrrhiza was developed. Glycyrrhiza extract was directly chromatographed on SP‐Sephadex C‐25 (H+) and QAE‐Sephadex A‐25 (Cl−) with distilled water and 0.2Msodium chloride (pH 13.50) as the eluents, respectively. The eluate was then hydrolyzed with perchloric acid and determined turbidimetrically at 530nm.With this method, glycyrrhiza samples collected in Taiwan and Singapore were found containing 17.21±0.45% and 7.49±0.35% of triterpene glycosides, calculated as glycyrrhizin, r

ISSN:0009-4536    

DOI:10.1002/jccs.198200007

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractSalicylidene‐o‐aminobenzothiol and its 5‐chloro and 5‐bromo derivatives, dibasic tridentate Schiff bases, dervied from the condensation ofo‐aminothiol and Salicylaldehyde, 5‐chloro salicylaldehyde and 5‐bromo salicylaldehyde, were used for coordination with Zr(IV), Th(IV) and UO2(VI) metal inos. The I:I (metal‐ligand) stoichiometry of these complexes is shown by elemental analysis and conductometric titrations. Molecular structure of these complexes are proved by Infra‐red spectroscopy and thermogravimetric analysis. Magnetic susceptibility measurements of Zr(IV), Th(IV) and UO2(VI) complexes show their diamagnetic and octahedral geometry. Results show that all the complexes have solvent molecules in coordinati

ISSN:0009-4536    

DOI:10.1002/jccs.198200008

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractA spectrophotometric method for the determination of trace amounts of tantalum (V) with 5–7‐diiodo‐8‐hydroxyquinoline is described. With this reagent tantalum forms a yellowish‐orange coloured complex which is stable in thepH range of 8.5–9.0. The coloured complex obeys Beer's law over the concentration range of 1–10μgtantalum (V)ml−1at 415nmin aqueous solution with a molar absorptivity of 5.305×103l mol−1cm−1. The metal; ligand ratio ML2was confirmed by Job's continuous variation and mole ratio methods. The method was used to determi

ISSN:0009-4536    

DOI:10.1002/jccs.198200009

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY

摘要:

AbstractThe stability constants of the complexes between the trivalent lanthanide series of cations and series of azo‐β‐diketone ligands are reported. The measurements were conducted at 30° at an ionic strength of zero, in 100% methanol.The relation between the overall stability constant (log β2) and atomic number of the lanthanide elements, shows a buffer zone at the gadolinium area. The relation between (log β2) and the basicity of the studied ligands (ΣpK's) are also, discussed.The overall stability values obtained reflected a great affinity of the organic ligands for chelation with lanthan

ISSN:0009-4536    

DOI:10.1002/jccs.198200010

出版商:WILEY‐VCH Verlag    

年代:1982

数据来源: WILEY