bluuebunny/crossref_metadata_2025 huggingface dataset:
Micelle‐Counterion Interaction, I. Critical Micelle Concentrations OF SDS Under the Influence of Copper Counterion
Authors: Su Shyh‐Gang , Chen Yie Lane , Mou Chung Yuan
Published: June 2015

We investigated the effect of counter ion (Cu2+) adsorption on Sodium Dodecylsulfate and Sodium Tetradecylsulfate micelle by three different techniques: surface tension decrease, copper‐selective electrode and electric conductivity. The effect of added copper ion on critical micelle concentration (CMC) was determined. The effectiveness of these three techniques was critically evaluated. It is concluded that copper ions are able to strongly displace Sodium ions from the micellar surface.
Carbonylation of Benzyl Halides Over Two‐Phase Catalyst of Iron Pentacarbonyl
Authors: Ou Chau‐Ban , Liu Ling‐Kang
Published: June 2015

Carbonylation of benzyl halides to phenylacetic acid was studied in a two‐phase system with iron pentacarbonyl as the catalyst precursor. The solutions consisted of a benzyl halide and iron pentacarbonyl in benzene and tetrabutylammonium hydrogen sulfate in aqueous sodium hydroxide. Stirring under carbon monoxide readily produced phenylacetic salts in aqueous phase which were then acidified and extracted with ether. The yields of phenylacetic acid from benzyl iodide and from benzyl bromide were similar at a evel of about 50percnt;, that of the latter being higher by 1%. The yield from benzyl chloride was far less, at a level of only 21%. The rate as studied with gas chromatography was found to decrease in the order benzyl iodide>benzyl bromide>benzyl chloride.
A Study of the Human Urinary Steroid Metabolic Profile Using A DB‐1 Fused Silica Capillary Column
Authors: Sye Wen‐Fa , Cheng Chia‐Tsung
Published: June 2015

This paper reports the performance of a DB‐1 fused‐silica capillary column for analysis of mixtures of methoxime‐trimethylsilyl ether (MO‐TMS) derivatives of human urinary steroid extracts. DB‐1 is a non‐extractable bonded phase, equivalent in polarity to SE‐30 and OV‐1. In addition, a small reversed‐phase Sep‐Pak C18 cartridge is used for extraction of steroid conjugates from urine, and for the extraction of freed steroids liberated by hydrolysis. Examples of urinary steroid analysis in normal adult males and in patients with multiple myeloma using the DB‐1 bonded phase fused silica capillary column are described.
An Extended Dienylium Terminus to Nucleophilic Addition with Tricarbonyl [3‐(1‐5‐η‐4‐Isopropoxycyclohexa‐2, 4‐Dienyl) Ethyl Acetate] Iron Hexafluorophosphate
Authors: Ong Chi‐Wi
Published: June 2015

A study of the regioselectivity in nucleophilic addition to tricarbonyl (dienylium) iron complexes having an acetoxyethyl group (or methoxyethyl group) is reported. Reaction of the acetoxyethyl dienylium complex with the potassium salt of methyl 2‐oxocylopentanecarboxylate was found to give a new product and a mechanism is proposed.

The regioselectivity to nucleophilic addition was shown to be dependent on the use of an alcohol protecting group as in tricarbonyl (dienylium) iron complexes (5) and (15).
A Study on the Dissolution of Ferric Oxide in Aqueous Hydrochloric Acid Solutions
Authors: Liu Ling‐Kang , Dai Chih‐Mei , Lin Yueh‐Hwa
Published: June 2015

The effect of hydrochloric acid concentration and the effect of temperature on the rate of dissolution of Fe2O3 have been investigated. Being heterogeneous, the dissolution reaction has been characterized to have an apparent activation energy of 21.5 Kcal/mol for a 7.11 m aqueous hydrochloric acid solution at temperatures between 273 and 373°K. The rate is linearly correlated to the mean activity of hydrochloric acid in the range from 1.3 to 10.8 m at 300°K.
Atomic Absorption Spectrophotometric Determination of Copper (I) after Adsorption of its 4′‐(p‐Methoxyphenyl)‐2, 2′:6′, 2″‐Terpyridine Tetraphenylborate Ion‐Associated Complex on Microcrystalline Naphthalene
Authors: Lin Jenn‐Lin , Satake Masatada
Published: June 2015

A new atomic absorption spectrophotometric method has been developed for the trace determination of copper after adsorption of its 4′‐(p‐methoxyphenyl)‐2, 2′:6′,2″‐terpyridine tetraphenylborate ion‐associated complex on microcrystalline naphthalene. This complex is adsorbed on microcrystalline naphthalene in the pH range 0.5‐11.0 by shaking for a few seconds. The solid mass so formed is separated by filtration, dissolved in dimethylformamide and the absorbance is measured at 324.7 nm. Beer's law is obeyed in the concentration range 5.0‐60.0 μg of copper in 10 ml of the final dimethylformamide solution. The replicate determinations of a sample containing 30 μg of copper gave a mean absorbance of 0.171 with a standard deviation of 0.0019 and a relative standard deviation of 1.11%. The method has been applied to the determination of copper in certain standard reference materials.
Gravimetric and Colorimetric Determinations of Copper, Cobalt, Zinc and Mercury with 1‐(2‐Methylindole‐3‐Acetyl)‐4‐Arylthiosemicarbazide
Authors: Barsoum B. N. , Kadry Azza. M. , Ibrahim Y. A. , Hanna H. R. , Sakla A. B.
Published: June 2015

1‐(2‐Methylindole‐3‐acetyl)4‐arylthiosemicarbazides have been prepared and were used as reagents for gravimetric and colorimetric determinations of copper, cobalt, zinc and mercury. The synthesis of the same metal complexes of these thiosemicarbazides as a potential biological derivatives was also described.
Studies on the Constituents of Camptotheca Acuminata Decne, II. The Constituents of Fresh Fruits,
Authors: Wu Tian‐Shung , Chen Ming‐Tyan , Kuoh Chang‐Sheng , Tien Hsien‐Ju , Yeh Mou‐Yung
Published: June 2015

Camptothecin, ethyl caffeate, ursolic acid, betulinic acid, and inositol have been isolated and characterized from fresh fruits of Camptotheca acuminata Decne (Nyssacese).
Optical Rotation of Time‐Reversal Degenerate States
Authors: Chiu Ying‐Nan
Published: June 2015

It is shown that time‐reversal (doubly‐) degenerate, many‐electron states in molecules of point‐group symmetry C3, C4, C6, S4, and S6 and T etc., can have non‐vanishing matrix elements over a time‐odd (electric dipole‐electric dipole) polarizability operator contributing to optical rotation. In agreement with well‐known results for Kramers' doublets, the optical rotations of the two separated and oriented states of this doublet have opposite signs in this polarizability mechanism, and they have the same sign in the time‐even pseudoscalar mechanism which is the usual natural optical rotation of chiral molecules. These results are proven, in an alternative formulation using time‐reversal in a second‐order process, to hold regardless of even or odd numbers of spins—in contrast to the first‐order processes such as the Jahn‐Teller effect. The universality of time‐reversal in spin, orbital and rotational angular momentum, in point and continuous groups, is show in a unified treatment with consistent phases. It was shown also how time‐reversal symmetry can resolve the ambiguities in lower point‐groups and determine relationships for which the point‐group symmetry is powerless.
Chemiluminescence of CaCl From the Ca+Cl2 Reaction in Argon Matrix
Authors: Guo Sui‐Whei , Chang Ju‐Wei , Lee Yuan‐Pern
Published: June 2015

Visible chemiluminescence in the 5800‐6600 Å region was observed from the Ca+Cl2 reaction in an argon matrix. The longer wavelength doublet progression is assigned as the A2Π3/2, 1/2→X2Σ+ transition of CaCl, with v00= 16189 and 16126 cm−1, respectively. Emission from the vibrationally excited v' = 1 level of the A state was also observed. This is the first observation of resolved spin‐orbit components in matrix chemiluminescent reactions. The progression with v00=16855 cm−1 was assigned as the B2Σ+→X2Σ+ transition of CaCl. Both transitions showed very small matrix shifts in the T2 values. A weak band at 17185 cm−1 was assigned as either the E2Σ→B2Σ+ or the a4Σ+→A2Π transition of CaCl. Ca atomic emission at 4232 and 6574 Å was also observed and it was attributed to the energy transfer processes from excited CaCl radicals.
The Measurement of the Dispersion of Pd/C Catalysts
Authors: Chen Nan , Wei Yu‐Chen , Yeh Chuin‐Tih
Published: June 2015

A 10 w/o Pd/C catalyst from Johnson Matthey has been examined by three different techniques: chemisorption, line broadening of X‐ray diffraction, and TEM (transmission electron microscopy) to investigate the size of the palladium crystallites. The dispersion of this catalyst was determined to be 20%. Among these techniques, the X‐ray diffraction was found to be the most convenient method. Through this method, the dispersion of Pd was found to decrease on catalyzing hydroxylamine reactions at 330 K. The deactivation of Pd/C for these reactions was correlated to the sintering of palladium. H2 chemisorption at 373 K was found to be a good way to accurately measure the number of active palladium sites in the Pd/C catalysts.
Polymerization of Allylhalides, Butadienes and Acetylenes Induced by Active Uranium Powder
Authors: Chang C. C. , Cheng C. P. , Chang C. T.
Published: June 2015

Allylhalides, butadienes and acetylenes were reacted with an active uranium powder which was prepared via electrolytic amalgamation. The reactions were conducted under a mild condition and brought forth a series of oligomers and polymers. The structures were characterized by means of IR and NMR spectroscopy. Possible reaction routes are suggested.
An Improved Synthesis of Insect Sex Attractant: CIS‐7‐Dodecenyl Acetate
Authors: Kao Yi‐Mei , Shiao Min‐Jen
Published: June 2015

An improved synthesis is described for cis‐7‐dodecenyl Acetate, a component of the sex pheromone of the cabbage looper and agrotis ipsilon. The synthesis is carried out in a five step sequence with 1,6‐hexanediol as the starting material. The method gives an improved yield (44%) over previous synthetic methods.
Taiwanin H, A New Lignan from the Barks of Taiwania Cryptomerioides Hayata
Authors: Kuo Yueh‐Hsiung , Lin Yih‐Tsung , Lin Yau‐Tang
Published: June 2015

A new lignan, taiwanin H, has been isolated from the barks of Taiwania cryptomerioides Hayata and elucidated as formula (6a) by chemical and physical evidence.
Mossbauer Study of the Effect of Intraligand Substituents on the Spin Crossover in Solid (Dithiocyanato)BIS(N‐Substituted‐Phenyl‐2‐Pyridinaldimine) Iron (II)
Authors: Wei H.H. , Kao S.P.
Published: June 2015

The spin transition of high‐spin (sT2⇄)low‐spin (1A1) of (dithiocyanato) (N‐phenyl‐2‐pyridinaldimine) iron (II) complexes can be altered by substituents on the phenyl ring. Mössbauer spectra at 78K for the 4‐substituted derivatives (with the exception of the 4‐OH‐substituted derivative) indicate that the fraction of low‐spin states increases with decreasing substituent electron‐withdrawing ability, as measured by the Hammet σ constant (4‐OCH3<4‐CH3CONH 4‐C6H5<4‐CH3<4‐H<4‐Cl<4‐NO2). In addition, the effect of methyl‐substitution at the ortho‐, meta‐ or paraposition of the phenyl ring on the spin transition was examined. Mössbauer spectra of these methyl‐substituted complexes reveal quite different spin equilibria.
Mixed Ligand Complexes of Chromium (III) Ethylenediamine Tartrate: A Polarographic Study
Authors: Sharma Jyoti , Kumar Arvind , Puri B.K.
Published: June 2015

Polarographic techniques have been used to investigate the complexing behaviour of chromium (III)‐ethylenediamine‐tartrate in aqueous solution. These complexes are reduced irreversibly at the dropping mercury electrode. The stability constants have been calculated by the method of Sundaresan and Sundaram. The values of the kinetic parameters; standard rate constant (Ks), transfer coefficient (α) and activation energy (Q) have also been calculated in each case.
Electrode Kinetics of Concentrated Sulfide Ion in Basic Solutions
Authors: Shih Yen‐Shiang , Lai Chih‐Chong
Published: June 2015

The diffusion coefficients of sulfide ion in 5 M NaOH solution with concentrations of (0.02–0.3)M at temperatures 24–50°C were determined using a rotating‐ring‐disc Pt electrode to be (0.5–2.0)×10−5 cm2/sec. The reaction order of the sulfide oxidation to sulfur was calculated to be 0.42 which implies one‐electron transfer as the rate‐limiting step and the reaction rate constant was found to be kf=2.57×10−5 exp(‐0.14ZFπ/RT).
Prediction of the Acid Strength of Some DI‐ and Trisubstituted Phenols
Authors: Nassar Ahmed M. G. , Abou‐Ali Samir A.
Published: June 2015

The dissociation constants of some di‐and trisubstituted phenols were determined potentiometrically. The pK's values were calculated and correlated with those of monosubstituted phenols. The predicted pK's based on additivity principle of the substituent effects were compared with the experimental findings.
The Studies of the Resonance Raman Scattering and the Chemical Reactions Involved in the Gaseous Iodine Bromide Under Argon Ion Laser Light
Authors: Chang Hua , Wang Jia Lin , Tzeng Gwo Dean
Published: June 2015

The resonance Raman spectra of gaseous iodine bromide IBr have been studied with the excitation of various argon ion laser lines from 5017 to 4579Å. The fine structures of the fundamental and few overtones of IBr are also studied by various power of 4880Å laser line. The resonance Raman scattering is found to be strong as that of Br2 and ICI. A new term “apparent spectroscopic temperature” is suggusted for the case of the resonance Raman scattering. The apparent spectroscopic temperatures measured in this cell show that the system is not in thermal equilibrium. Br2 is the hottest and I2 is the coldest. IBr is in the middle. Unfortunately, no chemical reaction enhanced phenomenon is found although there should be some chemical reactions occurring under the laser light. The initiating reaction is the photodissociation of the main component IBr which also has large absorptivity. Because of the non‐crossing between the B3Π and the 1Π states, the primary products of the photodissociation should be I and Br. The chemical reactions of I and Br with IBr follow. The reactions of I and IBr is endothermic but the reaction of Br with IBr is exothermic. Therefore vibrational hot Br2 is produced and its apparent spectroscopic temperature should be higher. On the other hand, the apparent spectroscopic temperature of I2 is lower.
Thymolphthalin as an Analytical Reagent: 1. Spectrophotometric Determination of Ferricyanide and Ferrocyanide
Authors: El‐Shahat M.P. , El‐Sayed A.B. , Abdel‐Badie M.M. , Amer A.I.
Published: June 2015

Thymolphthalein (I) as an acid‐base indicator is successfully reduced in sodium hydroxide medium and zinc dust into a colorless reagent (Thymolphthalin (III)). The latter is used as an analytical reagent in the colorimetric determination of some mildly strong oxidising agents such as potassium ferricyanide.

Ferricyanide, ferrocyanide and a mixture of both are spectrophotometrically determined at 592 nm. Dichromate oxidises ferrocyanide to ferricyanide without interference on the reaction. The results obtained showed that the system does obey Beer's law over the concentration range 20–170 ug ferricyanide per 25ml. The molar absorbitivity is (4.28+0.02)×103 cm2 mg−1 mole‐1.
Preparation of 3‐Aryl‐4‐(5‐ARYL‐Δ2‐1,2,4‐Oxadiazolin‐3‐YL)Sydnones and their Conversion into 3‐ARYL‐4‐(5‐ARYL‐1,2,4‐Oxadiazol‐3‐YL)Sydnones
Authors: Yeh Mou‐Yung , Tien Hsien‐Ju , Fuchigami Toshio , Nonaka Tsutomu
Published: June 2015

3‐Aryl‐4‐(5‐aryl‐Δ2‐1,2,4‐oxadiazolin‐3‐yl)sydnones (5) were synthesized in high yields by the reaction of 3‐arylsydnone‐4‐carboxamide oximes (prepared from the corresponding 3‐arylsydnone‐4‐carbonitriles) with aromatic aldehydes in the presence of acid catalysts. No reaction occurred when aliphatic aldehydes were used. The oxadiazolin‐3‐ylsydnones (5) were easily converted into the corresponding 3‐aryl‐4‐(5‐aryl‐1,2,4‐oxadiazol‐3‐yl)sydnones by N‐bromosuccinimide oxidation. The 3‐arylsydnone‐4‐carbonitrile oxides were synthesized in good yields by N‐bromosuccinimide oxidation of the corresponding 3‐arylsydnone‐4‐carboxaldehyde oximes.
New Observations on the Belousov‐Zhabotinskii Reaction. The Oscillating Reaction of Organic Gallic Acid and Potassium Bromate Catalyzed by 1,10‐o‐Phenanthroline‐Iron(II) Complex
Authors: Jwo Jing‐Jer , Chang Eng‐Fen
Published: June 2015

The oscillating reaction involving organic gallic acid (GA), potassium bromate, and a metal ion complex has been reinvestigated. In contrast to other previous reports, this oscillating reaction is catalyzed by the [Fe(phen)n]2+ ion (phen = 1,10‐o‐phenanthroline, n=1, 2, 3) rather than by the cerium ion. The characteristics of the oscillations depend on the temperature and on the concentrations of the potassium bromate, gallic acid, [Fe(phen)n]2+, and sulfuric acid. A cyclic voltammetric study indicates that the redox potential and the reversibility of the [Fe(phen)n]2+/3+ couple play a major role in catalyzing this oscillating system.
Electron Spin Resonance Analysis of Carbon on Ruthenium Catalysts
Authors: Chen Yu‐Wen
Published: June 2015

Electron spin resonance (ESR) spectra of carbon radicals on Ru/Al2O8, catalysts have been studied. Carbon monoxide treatment resulted in three kinds of sorbed species: a weakly sorbed CO species associated with the anisotropic spectrum; a more tightly sorted carbon species, perhaps amorphous carbon; and another carbon species, which is essentially unreactive with oxygen and may be graphitic carbon.
Catalytic Photometric Determination of Selenium by Flow Injection Analysis
Authors: Hwang J. M. , Wei T. S. , Chen Y. M.
Published: June 2015

A method is developed for the determination of trace amounts of selenium by flow injection analysis based on the catalytic effect of this element. Catalytic enhancement by selenium for the reduction of picrate ion by sodium sulfide was used and photometrically measured at the wavelength, 470nm. Optimum conditions were determined for temperature, pH, the concentrations of picrate and sodium sulfide, and also the conditions of the flow system; injection of sample volume, flow rate and mixing coil length.

With these conditions a good linear relationship was obtained for selenium in the range from 0.1 ppm to 1.0ppm and the detection limit was about 5ppb (two times of the noise). Interference by the diverse ions can be avoided with the use of a precolumn cation exchanger (Dowex 50) and by masking with EDTA in the conditional stream.
Physical Characterization of Acid‐Doped Polyaniline
Authors: Yang Sze‐Ming , Tsai Li‐No
Published: June 2015

Polyaniline has been synthesized by the chemical and electrochemical oxidation of aniline. The conductivities increase by seven order of magnitude upon protonation. The IR absorption band near 1590 cm−1 shifts to a lower frequency upon protonation. Visible spectra vary with the degree of protonation and the applied potential. Cyclic voltammetry indicates that polyaniline exists in several forms.
Heterogeneous Photocatalytic Oxidation of Diphenylmethane on TiO2 Powder
Authors: Liang Jang‐Jeng , Liu Tai‐Jei
Published: June 2015

Benzophenone is produced in the photocatalytic oxidation of diphenylmethane in an oxygen saturated TiO2 suspension. The yield is found to increase with increasing solvent polarity. An electron transfer mechanism is proposed in which a pair of electron‐positive holes generated initially by illumination may transfer an electron to O2 and abstract an electron from diphenylmethane to form O2− and ϕ2CH2+; subsequently, ϕ2CH2+ will react with O2− to give the product.
Effects of Different Solvent Characteristics on the Proton‐Ligand and Ni2+‐, Sm3+‐, AND Yb3+‐ Ligand Formation Constants of 5,5‐Dimethyl‐Cyclohexane‐2‐(2‐Hydroxyphenyl)Hydrazono‐ 1,3‐Dione (DCPHD) in Various Mixed Aqueous Solvents‐(II)
Authors: Ramadan Atef A. T. , El‐Maraghy Salah B. , Aabdel‐Moez Mohammed S. , Taha Ali M.
Published: June 2015

Complex equilibria of DCPHD with proton and Ni2+, Sm3+, and Yb3+ ions has been measured in various mixed aqueous solvents, viz: isopropanol‐water, acetone‐water, ethanol‐water, and methanol‐water. Based on potentiometric equilibrium measurements of hydrogen ion concentration at 30°C, ionic strenght 0.10 M (KNO3) and in the above various mixed aqueous solvents, the values of the protonation constants of DCPHD and the stability constants of DCPHD with Ni2+, Sm3+, and Yb3+ have been evaluated. The variation of protonation and stability constants with the inverse of dielectric constant or mole fraction of the solvent was studied. Application of Fuoss expression and consideration of electrosatic and non‐electrostatic effects are made to explain the values of the constants.
Studies on Cage Compounds. Synthesis of 8,11‐Diazenediyl‐4,4‐Dimethoxy‐2,3,5,6‐Tetrachloropentacyclo[5.4.0.02,5.03,10.05,9]Undecane
Authors: Chou Teh‐Chang , Chiou Jong‐Hsin
Published: June 2015

The title compound (7) was synthesized in six steps from 1,8,9,10‐tetrachloro‐11,11‐dimethoxy‐endo‐tricyclo[6.2.1.02,7]undeca‐4,9‐diene‐3,6‐dione (4) in an overall yield of 36%. The key intermediate, 1,8,9,10‐tetrachloro‐11,11‐dimethoxy‐endo‐tricyclo‐[6.2.1.02,7]undeca‐3,5,9‐triene (12), obtained from 4 by reduction, mesylation and then 1,4‐elimination, was allowed to react with diethyl azodicarboxylate to afford the Diels‐Alder adduct 16. Photochemical closure of 16, followed by hydrolysis and decarboxylation, gave the title compound.

The title compound failed to give either the homopentaprismanone derivative 3 or the diene 9 by the photochemical or thermal elimination of molecular nitrogen.
A Study of the Silylation of 1,8‐Dihydroxynaphthalene
Authors: Yang M. H. , Wu T. Y. , Liu S. L.
Published: June 2015

Twelve compounds each having a six membered Si‐contained heterocycle, have been successfully synthesized. Of these eleven compounds have never been reported in the literature. The structures were confirmed by Spectral analysis and elementary analysis. The stability and properties of these compounds is also discussed.
A Facile Synthesis of 3,4‐Diamino‐2,5‐Diacylthieno[2,3‐b]Thiophenes from Disodium(Dimercaptomethylene)Malononitrile and α‐Halo Ketones
Authors: Fuchigami Toshio , Kandeel Zaghloul El‐Shahat , Nonaka Tsutomu , Tien Hsien‐Ju
Published: June 2015

Various kinds of α‐halo ketones readily reacted with disodium (dimercaptomethylene)malononitrile to give the corresponding 34‐diamino‐2,5‐diacylthieno‐[2,3‐b]thiophenes in good to excellent yields. The reaction was successfully extended to the synthesis of a thienothiophene derivative having two sydnone rings by using the 4‐(bromoacetyl)sydnone.
A Study of the Constituents of the Bark of Chamaecyparis Formosensis Matsum
Authors: Fang Jim‐Min , Sheu Chi‐Min , Cheng Yu‐Shia
Published: June 2015

Sixteen compounds were isolated from the bark of Chamaecyparis formosensis Matsum. These compounds include four categories: (a) long‐chain alcohols, acids and esters, (b) sterols and their glucosides, (c) o‐methoxyphenol and related compounds, (d) diterpenes of abietane, pimarane, secoabietane and totarane.
The Constituents of the Leaves of Chamaecyparis Formosensis Matsum
Authors: Fang Jim‐Min , Lai Lee‐Jen , Cheng Yu‐Shia
Published: June 2015

Forty one terpenoidal compounds were isolated from the essential oil of Chamaecyparis formosensis Matsum. The dominant component is α‐pinene. Other major components include β‐pinene, 3‐carene, α‐terpineol, γ‐muurolene, and kaurene.
The Cycloalkyl Ring Effect on the Spin State of Di(Thiocyanato)Bis(N‐Cycloalkyl‐Substituted‐2‐Pyridinaldimine) Iron(II)
Authors: Wei H. H. , Chiou B. J.
Published: June 2015

A new series of octahedral iron(II) complexes with the composition Fe(II) (N‐R‐2‐pyridinaldimine)2(NCS)2, where R=cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl, have been synthesized and the spin states of the iron atom have been studied by means of Mössbauer spectroscopy and magnetic measurement.
High Energy Fuels I: A Novel Preparation of Exo‐Tetrahydrodicyclopentadiene by Isomerization of Endo‐Tetrahydrodicyclopentadiene
Authors: Cheng Sheng‐San , Liou Kou‐Fu , Lin Yih‐Tsung
Published: June 2015

Endo‐tetrahydrodicyclopentadiene (IV) is isomerized in the presence of trifluoromethanesulfonic acid (I) to give exo‐tetrahydrodicyclopentadiene (V). At higher acid concentrations, the isomerization occurs instantaneously. The preferred molar ratio of I to IV is in the range 0.05 to 4.0 and the preferred temperature is in the range 20°C to 100°C. Under these conditions, virtually no admantane is formed and undesirable C10H16 isomers can be reduced to a minimum. Besides the homogeneous system, the acid catalyst also works in a two‐phase heterogeneous system. The spent acid in the heterogeneous system can be reused without losing catalytic effectiveness.
High Energy Fuels II: Gas Chromatographic Separation of Energetic Compounds Derived from Dicyclopentadiene
Authors: Lin Yih‐Tsung , Linc Chien‐Kuo , Liou Kou‐Fu , Cheng Sheng‐San , Chang Ming‐Ju
Published: June 2015

An effective gas‐liquid chromatographic separation of thirteen energetic dicyclopentadiene derivatives has been established using OV‐17 as the stationary phase. FID was chosen as the favorable detector after comparing its response factors with those of TCD. Using this method good repeatability, reproducibility and precision are obtained in both qualitative and quantitative analyses of compounds investigated.
A Mild and Efficient Method for the Carbethoxylation of Amines
Authors: Chen Ling‐Ching , Yang Shyh‐Chyun
Published: June 2015

3‐Carbethoxy‐1,3‐thiazolidine‐2‐thione [CTT(2)] has been prepared by treatment of 1,3‐thiazolidine‐2‐thione (3) with ethyl chloroformate and triethylamine. CTT(2) shows high reactivity towards the amines.
Improved Extraction Method and Chromatographic Separation of Ginsenosides from Ginseng Roots, Leaves and Ginseng Drug Preparations
Authors: Sye Wen‐Fa , Tsai Pai‐Feng
Published: June 2015

A new extraction method for ginsenosides from ginseng roots, ginseng leaves and ginseng drug preparations by Sep‐Pak C18 cartridges has been studied. Ginsenoside extraction by Sep‐Pak cartridges is a rapid, efficient, reproducible method. In addition, the extracts were analyzed by high performance thin layer chromatography (HPTLC) and reverse phase high performance liquid chromatography (HPLC). The major components of ginseng saponins were effectively separated using an ODS‐120T column.
Derivatization‐Gas Chromatographic Analysis of Nalidixic Acid in Tablets
Authors: Wu Shou‐Mei , Wu Hsin‐Lung , Chen Su‐Hwei
Published: June 2015

A simple and improved gas chromatographic method has been developed for the quantitative analysis of nalidixic acid. The method is based on the derivatization of nalidixic acid with pentafluorobenzyl bromide in acetone, using potassium carbonate as a base‐catalyst. The derivative obtained was chromatographed on an OV‐101 column and the pentafluorobenzyl ester of cinoxacin was used as an internal standard. The method was satisfactorily applied to the analysis of nalidixic acid in tablets, and the results agree well with those obtained using the UV absorption spectrophotometric method.
Stereocontrolled Syntheses of (4S, 5R)‐ and (4S, 5S)‐Dihydroxy‐N‐Decanoic Acid‐4‐Lactones Via Biochemical Methods
Authors: Wang Yi‐Fong , Yiin Shiow‐Ling , Chen Sy‐Heng
Published: June 2015

(4S‐5R)‐ and (4S‐5S)‐dihydroxy‐n‐decanoic acid‐4‐lactones have been synthesized in a stereocontrolled manner by a chemomicrobiological approach.
Sensitized Photooxygenation of 2,5‐Di‐Tert‐Butylfuran
Authors: Kuo Yueh‐Hsiung , Shih Kae‐Shyang
Published: June 2015

Sensitized photooxygenation of 2,5‐di‐teri‐butylfuran was carried out in methylene chloride at −75°C to give a labile ozonide 4a, which was heated in methylene chloride under reflux to afford six products after purification.
Structural and Mechanical Properties of Polybutadiene‐Urethane Elastomer
Authors: Chiu Wen‐Yen , Chen Leo‐Wang , Lee Shyh‐Hwang
Published: June 2015

A series of polyurethanes based on hydroxyl‐terminated polybutadiene (HTPBD) and cured with Bis‐(‐hydroxy ethyl)‐terephthalate (BHET) have been synthesized. Mechanical, microscopic and kinetic studies were carried out to elucidate the structure‐property relationships from the view point of phase separation. We studied the effects of the polymerization method, varying the hard to soft segment ratio and changing the hard‐segment domain structure on the properties of the subject materials.

Dynamic mechanical responses showed that the Tg of the soft‐segment at −60°C was independent of the hard‐segment content, which indicates that the copolymers were well phase separated. A higher hard‐segment content brought about a slight increase in the modulus, a moderate increase in the tensile strength and a decrease in the ultimate elongation.

The size of the hard‐segment domain, as estimated from electron micrographs, ranged from 60A to 100A. It was observed that a higher content of hard‐segments causes an increase in the hard‐segment domain size. In addition, a general survey of the reaction rate indicated that BHET is less reactive with diphenyl methyl diisocyanate (MDI) than with HTPBD.
Analysis of Phenolic Priority Pollutants by High Performance Liquid Chromatography with Electrochemical Detection
Authors: Whang Chen‐Wen
Published: June 2015

Application of high performance liquid chromatography coupled with electrochemical detection (HPLC/EC) to the analysis of phenolic priority pollutants was studied. This method is highly sensitive and selective. Under optimum experimental conditions, the detection limits range from 0.05 ng for phenol to 1.20 ng for pentachlorophenol. The method was successfully applied to the direct determination of trace phenols in industrial wastewaters.
A Study of Degradation of a Jet Fuel
Authors: Li Norman C. , Tzou Ji R. , Chang Hua , Wang Sung M.
Published: June 2015

Degradation of a jet fuel (JP‐5) derived from petroleum and manufactured by the Chinese Petroleum Corporation in Taiwan was determined using various methods. Fuel degradation was monitored in the presence of the following compounds: phenol, 2,6‐dimethylphenol, thiophenol, 2‐methylpyridine, copper powder and mixtures of some of these compounds both at room temperature and at 80°C. The extent of light scattering and the amount of copper drawn into JP‐5 from added copper powder are correlated with the extent of deposit formation due to degradation of the fuel. Copper promotes deterioration of JP‐5 because of Cu(II) complex formation. Electron spin resonance and cyclic voltammetric measurements confirm the presence of Cu(II).
Surface Acidity of Alumina Aluminum Phosphate
Authors: Yang Sze‐Ming , Lee Ming‐Jiq , Wu Shiaw‐Tzong
Published: June 2015

Alumina aluminum phosphates in various aluminum to phosphor ratios were synthesized. The pore size can be easily controlled. The surface is weakly acidic. The number of acid sites per unit surface area shows a maximum at Al/P=1.9. The dehydration activity of tert‐butanol correlates with the total acid amount, whereas the dehydration activity of isopropanol is related to both the mumber of acidic and basic sites.
The Structure of 3‐Phenyl‐4‐(N‐Carbamyl‐1,4,2‐Oxathiazolimin‐3‐yl)Sydnone, C11H7N5O4S·0.8 CH2Cl2
Authors: Ueng Chuen‐Her , Wang Yu , Yeh Mou‐Yung
Published: June 2015

The title compound (Mr = 373) crystalizes in the othorhombic space group P bna with a = 10.410(2), b = 11.658(4), c = 23.108(3) Å, V = 2804.4 Å Z = 8. The single crystal intensity data were collected using MoK∞ radiation (λ = 0.7093Å) at room temperature. The crystal and molecular structure was solved with the final agreement index R = 0.039 for 1046 observed reflections. The bond lengths N(1)‐ C(7) and C(7)‐C(8) of the title compound are slightly longer than those of 3‐substituted sydnone derivatives. This may be attributed to the steric effect arising from the interaction of the phenyl ring and the 4‐substituent with the neighboring atoms of sydnone ring. Both the title compound and 4‐acetyl‐3‐(p‐tolyl)sydnone have smaller dihedral angles between the sydnone ring and the plane of the sp2 orbital of the double bond of the 4‐substituent and both have shorter C(7)‐C(9) bond lengths than those of other similar sydnone derivatives.
Zinc(II), Cobalt(II) and Nickel(II) Complexes of 5‐Substituted‐1,3,4‐Thiadiazoles
Authors: Adam F. A.
Published: June 2015

Zn(II), Co(II) and Ni(II) complexes with some 5‐substituted‐1,3,4‐thiadiazoles (L1‐L4) have been prepared and characterized by conductivity, microanalysis, thermal analysis, infrared and electronic spectra measurements. All complexes behave as 1:1 electrolyte and the ligands are coordinated as bidentate molecules. The stability constants and energy of formation are determined and discussed on the basis of the ligands structure.
Paired Electrolysis of Aldoses in a Divided Flow Cell
Authors: Chou Tse‐Chuan , Liaw Shyue‐Jang , Hwang Bing Joe
Published: June 2015

Simultaneous anodic oxidation and cathodic reduction of aldoses in a divided flow cell were studied. The stream of the anolyte was an aqueous solution containing D‐glucose, sodium bromide, and sodium bicarbonate. The stream of the catholyte was also an aqueous solution containing xylose and sodium sulfite. The factors which affected both the anodic and cathodic reactions were studied. The results indicate that the flow rates and temperatures of the anolyte and the catholyte, concentrations of the aldoses, pH values and the material of electrodes significantly affect both anodic and cathodic yields. The selectivities of gluconic acid in the anode and xylitol in the cathode were very high. The power consumption of paired electrolysis in the flow system was less than paired electrolysis in a batch system.
The Electrochemical Behavior of Complexes of Cobalt and Nickel with δ‐Valerolactam at the Dropping Mercury Electrode
Authors: Katyal M. , Puri B. K. , Kumar Ashok , Lin Jenn‐Lin
Published: June 2015

The kinetics of the polarographic reduction of Co(II) and Ni(II) has been investigated in the presence of an increasing concentration of the complex forming agent δ‐valerolactam at pH 6.0 and at constant ionic strength (0.1 M KNO3,). In both cases the waves were found to be diffusion controlled and irreversible. The values of the kinetic para‐meters such as the forward rate constant K°f, k and the charge transfer coefficient αn have been calculated as a function of ligand concentration. The diffusion current was precisely proportional to the concentration up to a metal ion concentration of 3.5 mM. Hence, a straight line is useful as a calibration curve in the quantitative analysis of these two metal ions. The method has also been applied to the determination of these metals in certain alloys.
Isoochotensine, a New Spirobenzyusoquinoline Alkaloid from: Corydalis Ochotensis Turcz
Authors: Wu Tian‐Shung , Huang Shiow‐Chyn , Lu Sheng‐Teh , Wu Yang‐Chang
Published: June 2015

Separation of the phenolic fraction of Corydalis ochotensis afforded a new spirobenzylisoquinoline alkaloid, isoochotensine (1) and three known alkaloids, ochotensine (3), cheilanthifoline (7), and lienkonine (9) as their acetyl derivatives together with a known nonphenolic alkaloid, ochotensimine (5). Their structures were elucidated by the spectral data.
s‐p Separation Model Indo‐Mo Method and the Theoretical Study of 1H Hyperfine Coupling Constant
Authors: Chen Cheng , Sun Kuang‐Chung
Published: June 2015

We have recently developed a modification of the traditional semiempirical INDO‐MO method especially useful for open shell problems: INDO with s‐p separation (J. Chin. Chem. Soc., 32, 385(1985)). In order to show the reliability of our new method fifty seven free radicals and radical ions were selected as examples for our MO calculation.

We are particularly interested in the unpaired electron distribution of hydrogen atoms. A linear correlation analysis between the spin density and the isotropic hyperfine coupling constant (aH) for 1H has been carried out for these radicals and ions. Most of our calculated aH's are better than the results reported using the conventional INDO method.
Organotransition‐Metal Complexes of Multidentates 1. Synthesis and Characterization of N, N‐Bis(Pyrazol‐1‐Ylmethyl)Aminomethane and N, N‐Bis(3, 5‐Dimethylpyrazol‐1‐Ylmethyl)‐Aminomethane Derivatives of the Group VI Metal Carbonyls
Authors: Shiu Kom‐Bei , Vong Wen‐Jong
Published: June 2015

N, N‐bis(pyrazol‐1‐ylmethyl)aminomethane (bpam) and N, N‐bis(3, 5‐dimethylpyrazol‐1‐ylmethyl)aminomethane (bdmpam) reacted with M(CO)6 or M(CO)3(CH3CN)3 in acetonitrile to give respectively fac‐(bpam)M(CO)3 and fac‐(bdmpam)M(CO)3 in good yields (M=Cr, Mo, W). These complexes are characterized by elemental analysis, IR, and NMR and compared with the related polypyrazolylborate complexes of the group VI metal carbonyls.
Differential Pulse Polarographic Determination of Nitrate in AUT Solution
Authors: Lee Chi‐So
Published: June 2015

A differential pulse polarographic method for the determination of nitrate ion has been developed. With 0.5 M CaCl2 as supporting electrolyte, NO−3 is reduced to give a peak with E1/2=–1.836 Volt vs. the Ag/AgCl electrode. The differential pulse polarographic peak height is proportional to the nitrate concentration from 20 to 60 ppm. The detection limit for nitrate is 2 ppm in pure aqueous solution. In the determination of 40 ppm nitrate a relative precision (relative standard deviation) of less than 2% was achieved. Nitrite interferes seriously and should be absent if accurate results are required. The method has been applied to the determination of nitrate in Ammonium Uranyl Tricarbonate (AUT) Solution, results obtained by this method are compared to those obtained by ion chromatography. The agreement between the two sets of results suggests that the DPP method can be used with a fair degree of confidence.
Deprotonation/Alkylation Reactions of Sulfolenes
Authors: Chou Ta‐Shue , Yu Chin‐Fen
Published: June 2015

Deprotonation/methylation reactions have been carried out on a series of substituted 2‐sulfolenes and 3‐sulfolenes. For 2‐sulfolenes, both allylic and vinylic deprotonation reactions occur to give, after treatment with methyl iodide, 2‐methylated 3‐sulfolenes and 2‐methylated 2‐sulfolenes. These products are useful intermediates because substituted 3‐sulfolenes are precursors to substituted butadienes and 2‐alkylated 2‐sulfolenes are precursors to β‐functionalized trans olefins.
A Simple Method for Determining the Critical Micellar Concentration of a Surfactant
Authors: Chang C. Y. , Wang S. J. , Liu I. J. , Chiu Y. C.
Published: June 2015

This paper will present a simple method for critical micellar concentration (cmc) determination based on light scattering using a turbidimeter. The method does not require the optical clarification of the surfactant solution. The surfactant solutions were prepared from distilled water after boiling. Distinct cmc values were observed for polyoxyethylene mono n‐dodecylether, sodium taurodeoxycholate and sodium dodecyl sulfate. The cmc values obtained using the turbidity method were compared with cmc values obtained by the surface tension method and with data given in the literature. Values obtained by our simple method have comparable accuracy with data obtained from more elaborate experiments.
A Study of the Kinetics of the Sulfation of 2‐Octanol by Sulfamic Acid
Authors: Ho Wu‐Hsiung
Published: June 2015

The kinetics of the sulfation of 2‐octanol by sulfamic acid in dimetylformamide were studied. The rate of disappearance of sulfamic acid obeys the rate equation:

Rate=k[SA]

where [SA] is the concentration of sulfamic acid. The energy and entropy of activation are 3.1 ± 0.6 kcal/mol and 15±2eu

A possible mechanism is as follows: The sulfamic acid reacts with DMF to form DMF·SO3 which then reacts rapidly with 2‐octanol to form ammonium sec‐octyl sulfate.

The kinetics of the sulfation of 2‐octanol by sulfamic acid in dimethyl sulfoxide were also studied. The reaction is described by a similar first‐order equation. The energy and entropy of activation are 33.7±1.0 kcal/mol and 17±3eu.
Platium Film Electrodes (1) Platium Film on Ti or TiO2‐Covered Ti
Authors: Wang Chung‐Reng , Hseu Tong‐Ming , Lin Zui‐Feng
Published: June 2015

A platium film was formed on a Ti(Pt‐Ti) and on a TiO2(Pt‐TiO2‐Ti) substrate by the conventional electroplating method (ELP) and by the electroless plating technique (ELSP). The effective minimum film thickness was found to be 0.5 μm judging from the maximum electrocatalytic capablity in alkaline (1 M NaOH) water electrolysis. The film obtained from ELP is superior to that obtained from ELSP, being more tightly bound to the substrate, showing better coverage of the subsrate surface, and also being mechanically stronger. Comparisons with bright Pt and with Pt‐black electrodes were made and it is concluded that the electrodes newly prepared using ELP will work as well as Pt‐black electrods. The electrodes from ELSP are useful only as cathodes, and are not suitable as anodes.
A Two‐Dimensional 1H NMR Approach for Peptide Backbone Assignments: Gramicidin S
Authors: Yu Chin , Chen Chao‐Ming
Published: June 2015

Two‐dimensional NMR spectra of gramicidin S have been measured. With the combination of COSY (through bond interaction) and NOESY (through space interaction) spectra, it is possible to identify amino acid residues sequentially. It is found that the phase‐sensitive 2D technique is superior to the absolute value mode. A double quantum filtering technique could be combined with phase‐sensitive COSY experiments to obtain the optimum results.
An Unusual Reductive Debromination of 8‐Bromoguanosine by Tri‐n‐Butylphosphine
Authors: Chern Ji‐Wang , Lee Horng‐Yuh
Published: June 2015

A reaction of 8‐bromoguanosine with benzyl disulfide in the presence of tri‐n‐butylphosphine in aprotic or protic solvent afforded guanosine instead of 8‐bromo‐5′‐benzylthio‐5′‐deoxyguanosine through an unexpected reductive debromination.
Studies on Binuclear Co(II) and Cu(II) Complexes of Tridentate N‐(2‐Carboxyphenyl)Salicylideneimine
Authors: Mahmoud M. R. , El‐Gyar S. A. , Ibrahim S. A.
Published: June 2015

Homo Cu(II) and Co(II) binuclear complexes H[MLClMCl2] formed by using the donor properties of the cis two oxygen atoms of the tridentate N‐(2‐carboxyphenyl)‐salicylaldimine Schiff base derived from salicylaldehyde and anthranilic acid have been synthesized. It was found that the Cu(II) “complexed ligand” readily reacts with CoCl2 to form mononuclear Co(II) and binuclear oxygen bridged Co(II) complex [Co2‐L2](H2O)2. The structure of the so prepared complexes was investigated using microchemical analysis, molar conductance measurements as well as electronic and vibrational spectral studies. It was concluded that in the Cu(II) binuclear complex, the Cu(II) ion inside the “complexed ligand” has a planar structure while the other Cu(II) ion is distorted away from planarity. In the Co(II) binuclear complex, the Co atom of the “complexed ligand” is distorted from tetrahedral structure when it coordinates to the second Co atom.
Chelating Behaviour of Substituted 1‐Benzoyl‐4‐Phenylthiosemicarbazide
Authors: El‐Asmy A. A.
Published: June 2015

The preparation and characterization of a series of new coordination compounds of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) containing o‐methyl‐ or o‐chlorobenzoyl‐4‐phenyl‐3‐thiosemicarbazide (HMBPT, HCBPT=HL) are reported. The reaction products were investigated by analyses, electrolytic conductance, magnetic susceptibility, reflectance and IR spectral studies. The IR spectra show that HMBPT and HCBPT coordinate with the metal ions via different coordination sites (NS and/or NO). The spectral data support the suggestion that the ligands form his‐chelates with Ni(II) and Cu(II) of square planar stereochemistry and of general formulae ML2·H2O, where L is the uninegatively charged bidentate ligand. The Co(II) ion forms octahedral and tetrahedral structures with HMBPT and HCBPT, respectively. The ligand field parameters (D4, B and β) for the Co(II) chelates were calculated using the averaged‐ligand‐field approximation. The influence of the benzene ring substituents (o‐chloro or o‐methyl) on the stereochemistry are discussed. Also, the formation of the complexes in solution was tested by the pH‐metric method.
Thin Layer Chromatographic Detection and Separation of Metal Ion Complexes with Tridentate Schiff Base
Authors: Gupta Mala , Kansal B. D.
Published: June 2015

The Tridentate chelating, system present in Salicylidine o‐amino benzoic acid was used for complexation with Cu (11), Ni (11), Co (11) and Pd (11). The thin‐layer chromatographic (TLC) detection and separation of these complexes on Silica gel (G) layers was studied. The coloured spots of the complexes were quite visible without any visualizing agent. A maximum of four complexes could be resolved and identified. The coloured zones were eluted with solvent and characterise by elemental analysis and spectral studies. Colour of the complexes at λmax was measured.
Coupling and Cyclization of Sydnone Compounds
Authors: Tien Hsien‐Ju , Lee Yaw‐Kuen
Published: June 2015

Cyclization were occurred via the coupling reactions of some mercuric chloride derivatives of sydnone with LiPdCl3‐CuCl2.

A unique six‐membered ring, 3,3′‐ethylene‐4,4′‐bissydnone, was obtained by the cyclization reation of 1,2‐di[3‐(4‐chloromercuric)sydnonyl]ethane. However, the seven‐membered 3,3′‐trimethylene‐4,4′‐bissydnone and 1,3‐di[3‐(4‐chloro)sydnonyl]‐propane were obtained from the corresponding mercuric chlroide of sydnone. Onyl substitution reaction took place when 4,4′‐di[3‐(4‐chloromercuric)sydnonyl]biphenyl, 4,4′‐di[3‐(4‐chloromercuric)sydnonyl]benzene, di(p‐[3‐(4‐chloromercuric)sydnonyl]‐phenyl}methane and, di(p‐[3‐(4‐chloromercuric)sydnonyl]phenyl]ether were treated using the same process.
Studies of the Factors Controlling Regioselective Nucleophilic Addition to Dienylium‐Iron Complexes
Authors: Hwang Wen‐Shu , Liao Rong‐Li , Ong Chi Wi
Published: June 2015

Tricarbonyl(4‐alkoxyl‐1‐alkylcyclohexadienylium)iron complexes (I) react with metal‐cation enolate nucleophiles to give in most cases a mixture of products (II) and (III), resulting from attack at the C‐1 and C‐5 termini of the dienylium ring. Factors that control the regioselectivity of nucleophilic addition, including the steric and electronic effects of the 4‐alkoxyl and 1‐alkyl substituents, the degree of association between the enolate nucleophiles and their counterions, and the polarity of the solvents, were investigated.
Atomic Absorption Spectrophotometric Determination of Selenium
Authors: Kabil M. A.
Published: June 2015

An atomic absorption method has been developed for the determination of selenium in synthetic mixtures of geological samples. Thiourea and n‐butylamine are added as a matrix modifier for the precise and accurate determination.
Determination of Benzidine and its Congeners by Liquid Chromatography with Electrochemical Detection
Authors: Whang Chen‐Wen , Yang Lin‐Lan
Published: June 2015

High performance liquid chromatography coupled with electrochemical detection (HPLC‐EC) method has been developed for the determination of benzidine and its related congeners in wastewater at the low ng/mL level. With a µ‐Bondapak C18 column, 53% acetonitrile (pH 4.7), and electrochemical detection at +1.0 V applied potential, the detection limits range from 3 ng/mL for benzidine to 10 ng/mL for 3,3′‐dichlorobenzidine, assuming a 100 µL injection. The detection limits can be further lowered to the sub‐ng/mL level by incorporating a short precolumn into the HPLC system for on‐line sample enrichment. Recoveries are generally greater than 80% — except for benzidine and 3,3′‐diaminobenzidine which give 50–70% recoveries. Industrial wastewater samples from a coke‐plant and a plant producing 3,3′‐dichlorobenzidine based dyes were successfully studied via this method.
Synthesis of [µ‐1,2‐Phenylenebisphosphido‐P,P']Diironhexacarbonyl Complex and Its Reactivity
Authors: Liu Shiuh‐Tzung
Published: June 2015

The title compound was prepared from the reaction of o‐bisphosphinobenzene with nonacarbonyldiiron. The structure was determined by spectroscopic methods. The mechanism of formation of the complex and its reactivity are discussed.