bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the Solvent Extraction with Radio‐Tracers. II. Solvent Extraction of Polonium‐210 from Irradiated Bismuth with tri‐n‐butyl Phosphate
Authors: Chen Ying‐Mao 
Published: June 2015

AbstractExtraction study on polonium from large amounts of irradiated bismuth was made with diluted TBP solution. Polonium used in this work was Po‐210, which was prepared by the irradiation of bismuth according to the following nuclear reaction, . From this study the following extraction conditions were obtained.
Extraction from 7 N HCl was found to be most suitable.
Degree of the dilution of TBP with diluent was studied and TBP concentration at about 10% was found to be most effective.
With various kinds of the solvent as diluent, the following order of the extraction was found: o‐xylene>carbon tetrachloride>benzene>amy1 alcohol>chloroform.
Extraction of polonium with 10% TBP in o‐xylene from 7 N HCl solution, more than 85% was found to be extracted with a single extraction. Under these conditions only a negligible amount of bismuth was extracted. Thus, the separation of these two elements was attained with this method.From the study on the distribution coefficients dependence on the variation of the concentration of TBP or acidities, the species extracted by the organic layer was considered to be PoCl4·2TBP when TBP concentration was less than 50% TBP, but PoCl4·TBP when larger than 50% TBP.
Field Sweep Spin Decoupling of Weakly Coupled Unsymmetrical Three‐Spin System
Authors: Lin Wei‐Chuwan 
Published: June 2015

AbstractProton magnetic resonance spectrum of 25% (volume) methyl 2,3‐dibromopropionate in benzene exhibits a typical ABC pattern in which the four strong lines from each nucleus can be immediately recognized. The assignment of spectral lines and the determination of energy‐level diagram were thus straightforward.Field‐sweep spin decoupling experiment with respect to the outer transition‐square of the sample was found to be in complete analogy with two‐spin AX system. However, spin decoupling with respect to the inner transition‐square reveals a weak satellite line on each side of the decoupled A (or C) signal. These weak satellite lines are found to be due to JAB (or JBC) and may prove to be useful for the direct determination of JAB and JBC.
Activity Product Constant of Barium Rhodizonate
Authors: Pan Kuan , Chou Tzi‐Shan , Huang Teh‐Shoon 
Published: June 2015

AbstractElectrolytic behavior of rhodizonic acid (H2Q) was polarographically studied in a series of acetate buffers and ammonium buffers of various pR values at 20°, 25°, 30° and 35°. Two well‐defined waves were observed in the pH range of 1∼5 and 8∼9.4, but only one wave was observed in the pH range of 5.5∼7.0. Polarographic and conductometric titrations of rhodizonate with barium chloride and the reverse titration indicate the formation of BaQ. Solubility product constant Ksp and activity product constant Ko of BaQ were evaluated from the polarographic data at various temperatures, and were found to be log and log
Electroosmosis and Electrophoresis in Paper Electrochromatography of Uranyl Ion in Semicarbazide Hydrochloride Solution
Authors: Lai Tsai‐Teh , Wu Che‐Kuang 
Published: June 2015

AbstractPaper electrophoresis in semicarbazide hydrochloride solution has shown that uranyl ion forms unit positively charged complex at pH 2.25. In 0.4 M hydrochloric acid, no detectable uranyl‐chloro complexes were formed. Electroosmotic flow created a water film extending from the cathode to the anode, and rendered the transference number of uranyl ion to zero at the margin of the water film. An improved method of paper chromatography was presented.
Some Tri‐ and Tetra‐Xylenoxysilanes
Authors: Liu Sheng‐Lieh , Ho Chin‐Hsia , Lin Te‐Fu 
Published: June 2015

AbstractIsomeric trixylenoxysilanes and tetraxylenoxysilanes are synthesized to compare with the previously investigated dixylenoxy compyunds. As a result, characteristic absorption of Infrared at 960–950 cm−1 was proved and increase in density, refractive index, and elevation of boiling point are observed.
Synthesis of 2,4‐xylenoxysilanes
Authors: Liu Sheng‐Lieh , Lin Te‐Fu 
Published: June 2015

AbstractSix compounds of 2,4‐xylenoxysilane have been synthesized, and their physical properties are examined. Although 2,4‐xylenol is the only liquid compound among their six isomers, the 2,4‐xylenoxysilanes did not show different character as compared with other xylenoxysilanes which are derived from solid xylenols.
Determination of Vapor Phase Diffusivity for Toluene‐Air System and for Benzoic Acid‐Air System
Authors: Yuan H. C. , Cheng M. H. 
Published: June 2015

AbstractThere are several methods available for determination of diffusion coefficients. Stefan diffusion tube was most widely used for the measurement of vapor phase diffusivity in binary systems. It was proved theoretically that the radial concentration profile may be negligible in a thin cyclindrical section. It was also shown theoretically that the velocity profile does not affect the mass flux. This report considered longtitudinal diffusivity alone. The diffusivity of toluene‐air system was measured from 40°C to 70°C and that of benzoic acid‐air system was estimated from 140°C to 160°C.
Synthesis and Infrared Absorption Spectra of 5′‐methyl‐2′‐hydroxychalcones: I. 5′‐methyl‐2′‐hydroxychalcone and its 4‐Substituted Derivatives
Authors: Lin Chi‐Hsiung , Lin Chhiu‐Tsu , Yeh Chin‐Lung 
Published: June 2015

AbstractSeven 2′‐hydroxychalcone derivatives with a methyl group on the 5′‐position were synthesized. Infrared absorption spectra of these new compounds are discussed.
The Stabilities and Thermodynamic Properties of Copper (II), Zinc (II) and Cadmium (II) Chelates of trans‐1,2‐diaminocyclohexane‐N, N, N′, N′‐tetraacetic Acid
Authors: Hseu Tong‐Ming , Wu Shao‐Chung 
Published: June 2015

AbstractInteractions between trans‐1,2‐diaminocyclohexane‐N, N, N′, N′‐tetraacetic acid (H4DCTA or H4Z) and Cu(II), Zn(II) and Cd(II) ions has been investigated. The formation constants of the hydrogen chelates (MHZ−), and of the normal chelates (MZ2–), have been evaluated at 10°, 20°, 30° and 40°C, and an ionic strength of 0.10(KNO3). The former was done by a titration technique and the latter by a mercury indicator electrode technique. Enthalpy and entropy changes characterizing the formation of the normal chelates have been calculated at 25°C.
Supplementary Observations on the Chemistry of the Alkaloids of Berberine Series. II. The Ultraviolet Absorption Spectra of Berberines and Related Compounds
Authors: Sebe Eigai , Abe Seishi , Murase Noriyoshi , Shibata Yoshi 
Published: June 2015

AbstractThe ultraviolet absorption spectra of berbines and ϕ‐berbines consist of a single, weak and narrow band in which λmax position dependeds on the kind of auxochrome group i. e., methylenedioxy‐or dimethoxy group attached to 2–3 position. The effect of the auxochrome group at 11–12 position or 12–13 position is very small.The shape of the band of oxyberberine, oxy‐ϕ‐berberine and oxyprotoberberine are similar, especially those of the latter two substances resemble closely.Comparing with isoquinoline, the bands (b), (c) and (d) of G‐berberines and protoberberine are considered as characteristic of isoquinoline structure, while the band (a) in visible region is of berberinium structure, however, the absorption curve of ϕ‐berberines does not show any characteristic of isoquinoline or berberinium structure.
Cation Exchange Behavior of Actinium‐228 in Mixed Solvent Systems Consisting of Methanol‐Thiocyanate‐Water
Authors: Chen Ying‐Mao , Shu Rei‐Yuan 
Published: June 2015

AbstractCation exchange behavior of actinium‐228 in mixed solvent system consisting of methanol‐thiocyanate‐water was studied with Dowex 50 resin. Solvent systems containing 50 to 90% methanol and concentration of thiocyanate from 1F to 5F were used. The distribution ratios of actinium between resin and the solutions were estimated by batch equilibrium and elution peak methods. By plotting these distribution ratios for each solvent system against the concentration of thiocyanate, different correlations were found. The difference may be attributed to the fact that the different species were absorbed by the resin. Feasibitity of using the mixed solvent system to the separation of actinium from thorium, was also examined.
Chemical Studies of Formosan Cobra (Naja Naja Atra) Venom Part IV. Estimation of molecular weights of some purified protein fractions by sephadex gel filtration
Authors: Chang Qui‐Linn , Hu Chung‐Yuan , Lo Tung‐Bin 
Published: June 2015

AbstractMolecular weights of four purified fractions, Fractions VIII (cobraneurotoxin), IX (5′‐nucleotidase), XI (cardiotoxin) and XII (cardiotoxin) of Formosan cobra venom were estimated by gel filtration on Sephadex G‐100 and G‐75 columns.
Chemical Studies of Formosan Cobra (Naja Naja Atra) Venom. Part V. Properties of 5′‐Nucleotidase
Authors: Chen Yee‐Hsiung , Lo Tung‐Bin 
Published: June 2015

AbstractThe chromatographically, disc and microzone electrophoretically homogeneous 5′‐nucleotidase of Formosan cobra venom was prepared. This enzyme has molecular weight of about 10,000 as estimated by gel filtration and by total amino acid analysis. Maximal activity was exhibited between pH 6.5 and 7.0 in 0.1 M Tris‐malonate buffer. Mn++ and Mg++ ions enhance the activity. The maximal enhancement was obtained at the final concentration of 10−3 M regardless of substrate concentration. Ni++ and Zn++ ions inhibit the activity. It is heat stable up to 50° C for 2 min but complete inactivation occurs at 80° C. It shows a high specificity for hydrolysis of ribonucleoside‐5′‐phosphate but shows only 20% and completely inactive to deoxyribonucleoside‐5′‐phosphate and 2′‐or 3′‐nucleotide, respectively. Apparent Km and Vmax values were also determined for AMP, GMP, UMP and CMP.
Analysis of the Electronic Spectra in Polyphenyls
Authors: Ting Chen‐Hanson 
Published: June 2015

AbstractThough the spectra in polyphenyls are often broad and structureless, the general pattern of these spectra is very similar to those in polyacene series. The systematic behavior of the α, p, and β bands in p‐polyphenyls can be explained in terms of simple MO theory with the first order configuration interaction. The behavior of the p and β bands can also be approximately calculated by straightforward exciton theory. The usefulness of the exciton theory is best demonstrated in the case of m‐polyphenyls.
Sydnones IV. Synthesis of Sydnones Analogous to the Photochromic Compounds
Authors: Tien Jack M. , Hunsberger I. M. 
Published: June 2015

AbstractN‐(6‐methoxy‐3‐pyridyl)‐sydnone (I), N‐(4‐nitrobenzyl)sydnone (II‐1), and N‐(2‐nitrobenzyl)sydnone (II‐2) have been prepared. Condensation of 2, 4‐dinitrochlorohenzene with N‐(carbethoxymethyl)sydnone (II‐4) produced N‐[(2, 4‐dinitrophenyl) carbethoxymethyl]‐sydnone (II‐5). Under normal conditions none of them are photochromic.
Isomerization of Chemically Activated Methylcyclopropane and the Ratio of Trans‐ to Cis‐2‐Butene
Authors: Ho Shih‐Yeng 
Published: June 2015

AbstractThe isomerization of vibrationally excited methylcyclopropane and the trans‐ to cis‐2‐butene ratio were studied as a function of pressure at room temperature. The ratio is larger than unity at low pressures and within experimental error is about constant and close to unity at high pressures.
Studies on Polymerization of Vinyl Compounds Initiated by Metal Chelate I. Polymerization of Methyl Methacrylate with Ni (II) Benzoyl Trifluoroacetonate as an Initiator
Authors: Chen Chih‐Tsung , Lin Pi‐Chou , Hsieh Nang‐Chang 
Published: June 2015

AbstractThe polymerization of methyl methacrylate with Ni (II) benzoyl trifluoroacetonate was investigated. The rate of polymerization was proportional to the square root of the initiator concentration and 1.5 power of the monomer concentration. The activation energy for the overall polymerization was 13.4 Kcal/mole, which yields 17.6 Kcal/mole for the activation energy and 9.58 × 105 sec−1 for the collision frequency factor for the initiation.
Synthetic Studies of Nitro‐Chlorotropones and Trihalotropones
Authors: Hsiang Shi‐Fen Lin , Yang Paw‐Wang , Pan Shii‐Jeou , Chien Ching‐Ying , Chou Shine 
Published: June 2015

AbstractNitration of 2‐chlorotropone with fuming nitric acid gave 2‐chloro‐ 4,7‐dinitrotropone in good yield. 2,4,7‐Trichlorotropone, a new compound, and 2,4,7‐tribromotropone have been derived successfully from 2‐chloro‐4,7‐dinitrotropone by heating with hydrogen chloride or hydrogen bromide in acetic acid. The structures of 2‐chloro‐4,7‐dinitrotropone, 2,4,7‐trichlorotropone and 2,4,7‐tribromotropone have been confirmed on the basis of chemical facts together with the spectroscopical evidences. The chemical and physical properties of the above compounds have also been investigated.
Synthesis of Ethyl 7‐Flavonol‐Oxyacetates
Authors: Hsu K. K. , Chen F. C. , Lo M. S. 
Published: June 2015

AbstractTen new methoxy‐, nitro‐, and halogen substituted 2′‐hydroxy‐4‐carbethoxymethoxychalcones have been prepared by the condensation of 2‐hydroxy‐4‐carbethoxymethoxyacetophenone with substituted benzaldehydes. These chalcones have been converted to the corresponding flavonols.
Polarized Raman Spectra VI. A Short Note on the Raman Spectra of p‐Polyphenyls
Authors: Ting Chen‐Hanson 
Published: June 2015

AbstractThe Raman spectra of the p‐polyphenyls: benzene, biphenyl, p‐terphenyl, and p‐quaterphenyl, are compared with their electronic spectra. The relative intensity of the double bond stretching mode around 1600 Kaisers to that of the breathing mode around 1000K increases steadily when the phenyl chain is lengthened. This intensity ratio can be calculated using our theory proposed previously.1 The results are in very good agreement with the experimental observations
Polarized Raman Spectra VII Correlations and Assignments of Raman Lines in p‐Polyphenyls
Authors: Leu An‐Lu , Ting Chen‐Hanson 
Published: June 2015

AbstractThe Raman spectra of powdered biphenyl, p‐terphenyl, and p‐quaterphenyl are compared with each other and also with the Raman spectrum of benzene. Most Raman lines in polyphenyls can be considered as derived from normal vibrations in benzene. The intense lines are thus assigned and the correlations between them are established.
The Photochemical Reactions of Ketene‐Benzene Mixture
Authors: Hwang Der‐Yan , Ho Shih Yeng 
Published: June 2015

AbstractIn the photolysis of ketene with benzene in the gas phase, Cycloheptatriene (CHT) and totuene (Tol) have been observed as the products. The ratio, (CHT)/(CHT)+(Tol) are studied at various conditions. The difference of activation energy of formation between toluene and cycloheptariene is evaluated to be 4.76 kcal/mole.
The Molecular Structure of Cyclopropene as Determined by Electron Diffraction
Authors: Chiang Joseph F. 
Published: June 2015

AbstractThe molecular structure of cyclopropene has been determined by gas‐phase electron difraction. A least‐squares analysis was applied to the experimental molecular intensity to obtain the following geometric structural parameters: Cl‐C3=1.304±0.003A, C3‐C3=1.519±0.002A, C1‐H=1.077±0.012A, C3‐H=1.112±0.015A.
Chemical Constituents of Umbelliferous Plants. XIV. Coumarins from the Root of Angelica Tarokoensis Hayata
Authors: Yen Kun‐Ying , Yang Ling‐Ling 
Published: June 2015

AbstractXanthotoxin and byak‐angelicin were isolated from the root of Angelica tarokoensis Hayata. Imperatorin, bergapten and marmesin were also detected by thin layer chromatography.
Polyamide‐Silica Gel Mixed Layer Chromatography of Antipyretics
Authors: Chiang Hung‐Cheh , Liu Chu‐Chi 
Published: June 2015

AbstractNine antipyretics are well separated on a polyamide‐silica gel G (1:5.2) mixed layer with four solvent systems. The mixed layer is firmly bonded and easy to handle and store. The method is applicable for the identification of A. P. C. tablet and the detection of free salicylic acid in aspirin.
Infrared and Nuclear Magnetic Resonance Absorptions of Common Liquid Stationary Phases for Preparative Gas Chromatography
Authors: Liu Kwang‐Ting 
Published: June 2015

AbstractIt is well known that many liquid stationary phases for gas chromatography have a tendency to bleed at high temperature and/or at high flow rate. This problem is especially important in preprative applications, since the liquid phase may then be the contaminant of a pure component. Such contaminant can hardly be deteced by gas chromatography. However, for routine spectral analysis it may introduce certain extraneous peaks in both infrared and nuclear magnetic resonance spectra of the pure component. Consequently, it is desirable to have handy references to avoid misleading by those peaks.
Emulsion Polymerization of Vinyl Acetate at Low Temperatures
Authors: Shiau Rhong‐Chau , Yamaguchi Tadashi 
Published: June 2015

AbstractPolymerization of vinyl acetate (VAc) was carried out with potassium persulfate (KS) and ammonium sulfite as redox initiator in the presence of acetonitrile for the purpose of preparation of polyvinyl alcohol (PVA) of desired degree of polymerization (DP). The PVA obtained by this method at 0°C showed higher DP and lower solubility in water. It was observed that acetonitrile was a useful chain transfer agent in this polymerization system. It was also observed that ZnCl2 accelerated the polymerization of VAc and the over‐all activation energy of polymerization was 9.73 Kcal/mol. However, the stereoregularity of PVA obtained by the saponification of PVAc in this system was not improved by the presence of ZnCl2.
A Simple and Rapid Separation of Preservatives and Artificial Sweeteners by Polyamide Layer Chromatography
Authors: Wang R.T. , Chou S.S. 
Published: June 2015

AbstractA simple and rapid polyamide chromatographic method for the detection of 12 kinds of preservatives and 3 kinds of artificial sweeteners were reported. The results indicated that the method was good in sensitivity, separability and reproducibility.
Studies on the Constituents of Anona Squamosa L.
Authors: Yang Tsang‐Hsiung , Chen Chi‐Ming 
Published: June 2015

AbstractAnona squamosa L. (Fam. Anonaceae) has been used in folk medicine1 as amebicide, tonic, astringent and has antitumor activity against Ehrlich cancer cell in mice2,3. In order to search for the active constituents of Formosan antitumor plants, examination was made on the alkaloids of the roots of Anona squamosa L.Seven alkaloids (A‐G) and an non‐alkaloidal compound (H) were isolated from the basic and n‐hexane fraction respectively. Identification of these bases by spectral analysis and direct comparison of their infrared spectra, tlc and mixed melting point have proved to be non‐phenolic anonaine (I), michelalbine (III), oxoushinsunine (liriodenine) (IV) and phenolic L‐(+)‐reticuline (V), anolobine (VI). Examination of other two minor phenolic Base‐D, mp. 224–226°, Base‐E, mp. 231–233° (decomp) and an non‐alkaloidal crystal‐H, mp. 175–176° are now in progress.
Synthesis of Biflavonyl Ethers
Authors: Chen F. C. , Ueng T. , Chen C. Y. , Chang P. W. 
Published: June 2015

AbstractThree new biflavonyl ethers with 4′‐4″′ ether linkage (5∼7) and two haloflavonoids, 3′‐nitro‐4′‐bromoflavone(3) and the corresponding chalcone (2), have been synthesized.
Studies of Dipole‐Dipole Interactions of Acetone Molecules in Some Organic Solvents
Authors: Chang Chen‐Pin , Lin Tzu‐Fang 
Published: June 2015

AbstractA new technique which permits rapid and precise measurement of vapor pressure over dilute solutions was used here to investigate the intermolecular forces of acetone molecules in several inert organic solvents. In the dilute solution of acetone mole fraction less than 0.03, acetone dimers were found to be the main species in the solvents, cyclohexane and CCl4. And no associated species of acetone were found in benzene. The strength of dipole‐dipole interactions which stabilize the acetone dimer were found comparable to that of some hydrogen bonds and also greatly influenced by solvents.
Electronic Structure and Isomerization of Stilbene
Authors: Ting Chen‐Hanson , McClure Donald S. 
Published: June 2015

AbstractThe electronic structures of trans‐ and cis‐stilbene are calculated using Pariser and Parr's semiempirical method. The resonance integrals are adjusted so as to give the best agreement with the spectroscopic data. In addition, the potential surfaces of various excited states in stilbene during its isomerization process are calculated. Our results differ significently from those of Borrell and Greenwood2) who did not realized the importance of a doubly excited singlet state to the potential surface of the ground state of stilbene. Our improved potential surfaces suggests mechanism of various radiationless leading to photoisomerization and sensitized isomerization.
HMO and SCF Calculations on Acetylacetonate Anion, Phenyl Azide and Some Tetracyclic Hydrocarbons
Authors: Chang Chin‐An , Liang Bih‐Fong 
Published: June 2015

AbstractMolecular orbital calculations using the Hückel method, the ω‐technique and the Pariser‐Parr‐Pople SCF method are compared with one another. The effect of including the overlap integral is compared to that excluding it. The calculated quantities agree well with the available experimental values.
Mössbauer Study of Some Gamma‐ and Neutron‐Irradiated Iron Carbonyl Complexes
Authors: Cheng H.S. , Yeh S.J. , Cheng P.K. 
Published: June 2015

AbstractMössbauer effect experiments have been carried out on 60Co and reactor irradiated CFe(CO)3SCH1]2, [(C4H9)2SnFe(CO)4]3, (C6H5)1PFe(CO)4, (CH2)4[Fe(CO)2C3H5]2, and (CH2)4.(CO)2[Fe(CO)2C5H5]2. It was found that the Fe—CO bond is rather radiation resistant than are expected due to the π bonding character. The σ bonds such as C—H are labile to radiation. The presence of acyl carbonyl group increase the radiation resistant property of the molecule. The increase in the isomer shift values of the complexes with cyclopentadienyl groups were interpreted as a result of dehydrogenation.
Spectrophotometric Studies of Cobalt (II) Chelate of P‐(2‐Hydroxy‐1‐Naphthylazo) Benzenesulphonate
Authors: Hseu Tong‐Ming , Ko Su‐Ya 
Published: June 2015

AbstractCobalt(II) chelate of p‐(2‐hydroxy‐1‐naphthylazo)benzenesulphonate (orange II) has been studied spectrophotometrically in aqueous solution at 25° and at an ionic strength of 0.10 M. The formation of this chelate is pH dependent, the optimum pH range is between 9.5 to 10.8. Its mole ratio of ligand to cobalt(II) is 3 to 1 stoichiometry and the formation constant, logK, is determined as 19.17±0.13. By using the wave‐length of 357 mμ, determination of trace amount of cobalt(II) with the sensitivity of 0.077 y/cm2 is possible.
Structural Studies on Bitter Principle from Brucea Sumatrana
Authors: Chem Shi‐Chow 
Published: June 2015

AbstractThe main bitter principle isolated from the chloroform extract of the seeds of Brucea sumatrana was shown to be C24H32O11, which, upon treatment of sodium methoxide, gave bruceolide and senecioic acid. Partial structural elucidation of bruceolide was described.
A Thermochemical Study on the Formation of Oxalato‐Titanium(III) Complex
Authors: Pan Kuan , Hsin Shu‐Ching , Huang Teh‐Shoon 
Published: June 2015

AbstractThe thermometric titration of titanium(III) chloride with oxalic acid was carried out at 25°C. The molar ratio of titanium (III): oxalate was found to be 1:2, which indicates the formation of Ti(C2O4)2− ion in acid media. The limiting value of the heat of reaction between Ti(III) ion and oxalic acid in hydrochloric acid solution was found to be −1.5 Kcal mole−1 at 25°C.
Polarized Raman Spectra X. Polarized Raman Spectra of Naphthalene Single Crystal
Authors: Lin Tien‐Pin , Ting Chen‐Hanson 
Published: June 2015

AbstractThe polarized Raman spectra of naphthalene single crystal are recorded with a laser Raman spectrometer. Relative intensites of Raman lines in various polarizations are accurately measured by photon‐counting technique. All the strong lines are polarized in the c′c′ and bb polarizations, and the polarization data alone are not sufficient to decide the symmetry of a Raman active vibration. The oriented gas model is found not adequate to fully understand the results. The polarization data have to be interpreted in terms of the electronic spectrum of naphthalene.