bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Heat Capacity and the Entropy of Transition of Würster’s Blue Perchlorate
Authors: Chihara Hideaki , Nakamura Minoru , Seki Syûzô 
Published: July 2006

Abstract
The heat capacity of Würster’s Blue perchlorate (N,N,N′,N′-tetramethyl-p-phenylene-diamine perchlorate) has been measured between 66 and 200°K. A phase transition occurs at 189.9°K with its tail extending down to about 160°K. The transition is probably of the first order. The heat and the entropy of the transition are 408.6±4.5 cal./mol. and 2.19±0.02 cal./deg.mol. respectively. The magnetic susceptibility of the specimen at room temperature indicates that the paramagnetic spin density is 100±3%. The experimental results have been compared with current theories, and it has been inferred that some unknown structural changes are involved in the phase transition.
Some Reactions of Mercuridiacetaldehyde
Authors: Murahashi Shunsuke , Nozakura Shun’ichi , Fuji Saburo 
Published: July 2006

Abstract
Mercuridiacetaldehyde is soluble in polar solvents and rather instable in the state of solution, yielding an insoluble and infusible substance. The decomposition reaction has been proved to include the formation of mercuri(I)-acetaldehyde Hg2(CH2CHO)2 by the cleavage of one of the Hg–C bonds. On the other hand, mercuridiacetaldehyde reacted with aldehyde reagents as usual aldehydes. The change in the infrared spectra on these reactions has been interpreted in terms of σ-π conjugation, as has been suggested previously by Nesmeyanov.
Nef’s compound, which is considered to be a mercuric salt of vinyl alcohol, has been found to be almost identical with the mercuri-(I)-acetaldehyde.
Kinetic Studies of Solvolysis. X. Transition from a van’t Hoff to an Arrhenius Intermediate Caused by Steric Hindrance at the Product-Formation Step of SN1 Reactions
Authors: Okamoto Kunio , Matsui Yoshihisa , Shingu Haruo 
Published: July 2006

Abstract
1. The SN1 reactions of benzhydryl halides and hindered nucleophiles, i. e., potassium 2,6-di-t-butyl-4-methylphenoxide (I), tri-n-butylammonium 2,6-di-t-butyl-4-methylphenoxide (III), tri-n-butylamine and tri-n-butylammonium phenoxide (II), proceed through an Arrhenius intermediate and obey good second-order kinetics in acetonitrile at 110–140°C, whereas in the same solvent the reaction with potassium phenoxide is a typical SN1 reaction with a van’t Hoff intermediate at 70–120°C. This transition of the characteristics of the intermediates from a van’t Hoff to an Arrhenius type has been explained as being due to steric hindrance at the product-formation step of the SN1 reactions.
2. The reactions of benzhydryl halides and some hindered nucleophiles, i. e., tri-n-butylamine, I and III, afford not products anticipated for the nucleophilic substitution in acetonitrile, but rather products derived from benzhydyl radicals, i. e., sym-tetraphenylethane, diphenylmethane and 1-(3′,5′-di-t-butyl-4′-hydroxyphenyl)-2,2-diphenylethane, whereas potassium phenoxide and II give rise to substitution products typical of the nucleophilic reactions, i. e., benzhydryl phenyl ether and p-benzhydrylphenol. A one-electron transfer mechanism between these hindered nucleophiles, such as tri-n-butylamine, I and III, and the SN1 intermediate has been suggested for the formation of benzhydryl radicals.
The Trifluoroacetate Method of Peptide Synthesis. I. The Synthesis and Use of Trifluoroacetate Reagents
Authors: Sakakibara Shumpei , Inukai Noriyoshi 
Published: July 2006

Abstract
The trifluoroacetates of various phenol, thiophenol and N-hydroxyimide derivatives, which are known as hydroxylic partners of various active carboxylic acid ester, have been synthesized, and it has been found that they are good reagents for the preparation of the respective active esters of acylamino acids by the ester-exchange reaction in pyridine. The new method is especially effective in the preparation of p-nitrophenyl, 2,4,5-trichlorophenyl and N-hydroxysuccinimide esters of acylamino acids, which are well known to be useful intermediates for peptide synthesis. The direct syntheses of peptides using these reagents, without the isolation of the intermediates, have been studied, and the new procedure has been found to be wise elongation of peptides.
The Effect of Temperature on Electrodialytic Demineralization
Authors: Weiner Susan A 
Published: July 2006

Abstract
The process of electrodialysis, as a means of demineralizing brackish water, is briefly described. Polarization, a limiting factor in the practical application of the process, is a function of several variables, one of which is temperature. In this study the temperature dependence of limiting current density and power consumption was examined. Experiments conducted at elevated temperatures (35.5°C and 40°C) showed that the limiting current densities are increased and the power consumption is decreased. At low temperatures (5°C) marked decrease in limiting current density was observed. Comparison of power consumption data at 40°C and 5°C show that significant differences occur with feeds more concentrated than 2000 p.p.m.
The Spectrophotometric Determination of Chromium with 2-Hydroxy-1-(2-hydroxy-4-sulfo-1-naphthylazo)-naphthalein (Sodium Salt)
Authors: Uesugi Katsuya , Katsube Yukiteru 
Published: July 2006

Abstract
A spectrophotometric method for the determination of traces of chromium (III) with 2-hydroxy-1-(2-hydroxy-4-sulfo-1-naphthylazo)-naphthalein has been described. Beer’s law is obeyed up to 1.2 p. p.m. of chromium. The spectrophotometric sensitivity is 0.0013 μg. Cr/cm2 based on an absorbance of 0.001 unit at 630 mμ. The accuracy and precision are satisfactory. The interference of foreign ions can be avoided by 8-hydroxyquinoline chloroform extraction or by acetylacetone chloroform extraction.
The Dehydrogenation of All-cis-5,11,14-Eicosatrienoic Acid to Arachidonic Acid
Authors: Takagi Toru 
Published: July 2006

Abstract
Ethyl 5,11,14-eicosatrienoate has been fed to fat-deficient rats. The gas chromatographic analysis of the fatty acids in the liver lipids and the alkali isomerization and oxidation scission of the eicosatetraenoate separated from the fatty acid has given evidence for the transformation of all-cis-5,11,14-eicosatrienoate to arachidonate.
Photoreduction of Methylene Blue and Thionine in Ethanol
Authors: Usui Yoshiharu 
Published: July 2006

Abstract
The photochemical behavior of methylene blue and thionine in ethanol is quite different from that of eosine in the same solvent. They are compared from several viewpoints below.
From the preliminary flash experiment and the kinetic results by steady illumination, it has been concluded that interaction between the ground state and the excited state dye is essential for photoreduction.
It is most probable that the overall scheme for the photoreduction of thiazine dyes in alcohol is similar to that in the case of the same dyes in a phosphate buffer solution.
Studies on Geometric Isomerism by Nuclear Magnetic Resonance. II. Geometric Configurations of Alkylidenecyanoacetic Esters
Authors: Hayashi Toshio , Igarashi Minoru , Hayashi Shoichi , Midorikawa Hiroshi 
Published: July 2006

Abstract
The Knoevenagel reaction of a methyl alkyl ketone with cyanoacetic ester gives a stereoisomeric mixture of α-cyano-β-alkylcrotonic ester. The NMR technique has been applied to the study of the geometric configurations of the mixture. It has been found that the isomer with a β-methyl group cis to the alkoxycarbonyl group always occurs predominantly. The magnitude of the cis-trans composition of the mixture is parallel to the steric requirement of the β-substituted alkyl group.
An Isotopic Exchange Reaction between Oxygen and Carbon Dioxide on Zinc Oxide
Authors: Titani Toshizo , Kiyoura Tadamitsu , Adachi Akira 
Published: July 2006

Abstract
Isotopic oxygen exchange reactions between carbon dioxide and zinc oxide, and between oxygen and carbon dioxide on zinc oxide, have been studied by the static method in the temperature range from 350 to 550°C. At any temperature carbon dioxide exchanges its oxygen atoms with those of zinc oxide rapidly. Within a few minutes after the initiation of the reaction, an isotopic equilibrium is established between the carbon dioxide in the gas phase and a certain part of the zinc oxide. It has been found that the, isotopic exchange between oxygen and carbon dioxide on zinc oxide takes place through the exchange between these gases and the oxygen atoms of the zinc oxide, that the limiting step is the exchange with oxygen, and that the carbon dioxide acts as an inhibitor of the exchange between oxygen and zinc oxide.
The Reaction of Ions in the Radiolysis of n-Butane in the Gas Phase
Authors: Miyazaki Tetsuo , Shida Shoji 
Published: July 2006

Abstract
The effect of ammonia in the radiolysis of n-butane has been investigated. In low pressure radiolysis, C3H8 and C2-products decrease upon the addition of ammonia while C3H6 increases. C4H8 increases sharply upon the addition of a small amount of ammonia, but it gradually decreases upon further addition. CH4 and H2 are not significantly affected by ammonia. These results have been interpreted in terms of the proton transfer reaction of ammonia with ions, and their rate constants have been estimated. The contribution of the excited ion to the C–C rupture has been concluded to be much more important than that of the excited molecule in low-pressure radiolysis.
In high-pressure radiolysis all the products from the C–C rupture, including CH4, decrease upon the addition of ammonia (or water).
The Determination of Micro Amounts of Polythionates. II. A Photometric Method for the Determination of Hexathionate by Means of Its Cyanolysis
Authors: Koh Tomozo , Iwasaki Iwaji 
Published: July 2006

Abstract
A photometric method for the determination of a small amount of hexathionate has been developed, a method depending on the formation of thiocyanate equivalent to the hexathionate, and on the determination of thiocyanate with an excess of ferric iron. A buffer solution is first added to a standard hexathionate solution in order that the pH of the mixed solution after the addition of the cyanide solution may be within an optimum range; otherwise the hexathionate undergoes alkaline decomposition as a result of the higher pH value caused by the addition of the cyanide. The conditions under which the reaction of hexathionate with cyanide is rapid and proceeds well to completion, have been established by varying the cyanide amount, the pH, the reaction time, and the temperature. Hexathionate can be determined by exactly the same procedure as that used for phentathionate.
Palladium(II) Complexes of β-Ketoamines Derived from Acetylacetone and Amines
Authors: Yoshida Emiko , Yamada Shoichiro 
Published: July 2006

Abstract
Numerous new palladium(II) complexes, Pd-(Aca.R)2, have been synthesized with β-ketoamines derived from acetylacetone and amines, where R represents methyl, ethyl, n-propyl, n-butyl, benzyl, phenyl, o-, m- and p-tolyl, and o, o′-xylidyl. It should be noted that when R denotes n-propyl or n-butyl, the palladium(II) complexes have been prepared successfully, although the free ligands can not be isolated in a pure form. This may be regarded as an example of the stabilization of a molecular configuration through co-ordination with a metal ion. The visible and ultraviolet spectra indicate that the palladium(II) complexes prepared in the present paper, which are considered to be square-planar in non-donor solvents as well as in the solid state, combine no additional pyridine molecules, even in pyridine. This is contrary to the previous observation that Ni(Aca.R)2 complexes combine two molecules of pyridine to form a sexaco-ordinated complex in pyridine.
The Formation Constants and the Rate Constants of the Electrode Processes of Thiocyanato-Indium(III) Complexes with the Dropping Mercury Electrode
Authors: Narusawa Yoshio , Hashimoto Jinzo , Hamaguchi Hiroshi 
Published: July 2006

Abstract
The formation constants,
Kj=[In(SCN)j(3−j)+]/[In3+][SCN−]j (j=1, 2, 3, 4), have been determined to be 50, 200, 120 and 1670 respectively. The electrode reaction proceeds as follows:
(1) At a higher ligand concentration ;
In(SCN)P(3−P)+ \ightleftarrows InSCN2++ (p−1) SCN−
(fast) (p=2, 3 and 4)
InSCN2++ 3e− + Hg → In(Hg) + SCN−
(rate constant (k1)B)
(2) At a lower ligand concentration:
InSCN2+\ightleftarrows Inaq3+ + SCN− (fast)
Inaq3+ + 3e− + Hg→ In(Hg)
(rate constant (k0)B
The rate constants, (k0)B and (k1)B at the standard potential are (0.64±0.16)×10−4cm./ sec. and (1.5±0.2)×10−4 (cm./sec.)/(mol./l.) respectively. The rate constant, k0f,h, at 0 V. vs. NHE was 4.77×10−12 cm./sec.
The Colloidal Behaviour of Ammonium Purpurate (Murexide) in an Aqueous Solution
Authors: Sangal Satendra P 
Published: July 2006

Abstract
By electrical conductance studies it has been found that ammonium purpurate behaves as a colloidal electrolyte and does not obey Beer’s law in concentrated solutions. The curve between the square root of the concentration and the molar conductance is not linear and resembles that of a colloidal electrolyte. The temperature of zero conductance has also been determined to be −20°C. The temperature coefficient per degree centigrade per hundred of the conductance at 35°C ranges between 0.86 and 1.65.
The Formylation of Amino Acids with Acetic Formic Anhydride
Authors: Muramatsu Ichiro , Murakami Masahiro , Yoneda Takahiro , Hagitani Akira 
Published: July 2006

Abstract
The formylation of amino acids with acetic formic anhydride has been studied. This anhydride is prepared by the reaction of acetyl chloride with sodium formate or, preferably, from ketene and formic acid. When various monoamino monocarboxylic acids are treated with acetic formic anhydride by a simple procedure and under mild conditions, N-formylamino acids were obtained in satisfactory yields.
Heats of Mixing for Binary Mixtures. II. The 1,3-Butanediol-Methylethylketone System
Authors: Takami Mitsumasa , Murakami Sachio , Fujishiro Ryoichi 
Published: July 2006

Abstract
The heats of mixing of 1,3-butanediol and ethanol with methylethylketone have been measured. The results obtained for these two systems have been compared with each other, and it has been found that there exist a considerable number of intramolecular hydrogen bonds of butanediol molecules in the ketone medium.
For the ethanol-methylethylketone system, the energy of the intermolecular hydrogen bond with ketone has been estimated to be about 4kcal. by using the thermochemical cycle; this value is nearly the same as those obtained for other monoalcohol-ketone systems in the previous paper.1)
Properties of the Dilute Solution of Poly-2-methyl-5-vinylpyridine
Authors: Miura Masaji , Kubota Yukio , Masuzukawa Teruaki 
Published: July 2006

Abstract
Nine fractionated samples of poly-2-methyl-5-vinylpyridine (PMVP) have been investigated by viscosity and light-scattering measurements at 25°C. In the range of the molecular weights from about 1×105 to 1×106, the following relationship between the intrinsic viscosity and the molecular weight in methanol has been obtained: [η] =0.80×10−4Mw0.76. The unperturbed molecular dimensions have been obtained using the recent theories of the solution behavior of high polymers. The results have been compared with those of other vinylpyridine polymers and polystyrene, and it has been found that the degree of the extension of PMVP is almost the same as those of the other polymers.
The Micelle Formation of Some Alkyl Sulfates in a Dioxane-Water Mixture
Authors: Shirahama Keishiro , Matuura Ryohei 
Published: July 2006

Abstract
The CMC values of three sodium alkyl sulfates with the number of carbon atoms 12, 14 and 16 in a dioxane-water mixture have been measured. The CMC-lowering effect of dioxane, especially appreciable in the case of sodium dodecyl sulfate, has been explained in terms of Shinoda’s equation. The CMC-raising effect of dioxane, which is the main effect in the case of sodium hexadecyl sulfate, has been explained by the decrease in the standard chemical potential, i. e., the free energy of transfer, ΔFtr, of the surfactant. An equation has been derived which expresses ΔFtr as a function of the dioxane concentration by applying Born’s equation and Hildebrand’s regular solution theory.
Electrolytic Thermocouple for the Determining Soret Coefficients and Heats of Transfer of Hydrochloric Acid
Authors: Ikeda Toshio 
Published: July 2006

Abstract
We have studied an electrolytic thermocouple formed by coupling two thermocells, consisting of electrodes of the same nature, and with different electrolytes, either hydrochloric acid or potassium chloride, but both of the same concentration; we have demonstrated that the Soret coefficient of hydrochloric acid relative to that of potassium chloride can be estimated from the initial thermoelectric powers of this electrolytic thermocouple, as long as the entropies as well as the heats of the transfer of the chloride ions may be assumed to be the same between these two electrolytes.
Agreements between calculations and observations have been roughly good in the range of concentration between 0.01 m and 1 m, though there are some uncertainties about the Soret coefficients of potassium chloride at higher concentrations. This method may have general applicability, particularly in the dilute region.
Thermal Decomposition of Acetaldehyde in the Presence of Hydrogen Chloride
Authors: Imai Naomi , Fujii Takeshi , Toyama Osamu 
Published: July 2006

Abstract
The thermal decomposition of acetaldehyde in the presence of hydrogen chloride has been investigated over the temperature range from 401 to 433°C. Hydrogen chloride, though it is not consumed, enhances the rate of decomposition to carbon monoxide and methane, thus acting as a catalyst. The rate law which holds when the [HCl]/[CH3CHO] ratio is sufficiently high is the same as that which holds in the absence of hydrogen chloride, being represented as k[CH3CHO]3⁄2 independent of the hydrogen chloride pressure. The most probable reaction scheme for explaining this rate law is CH3CHO+M → CH3+CHO+M (1), CHO → CO+H (2), H+HCl → H2+Cl (3), CH3+HCl → CH4+Cl (4), Cl+CH3CHO → HCl+CH3CO (5),CH3CO → CH3+CO (6), and Cl+Cl+M → Cl2+M (7), yielding the overall rate k11⁄2k5k7−1⁄2[CH3CHO]3⁄2. The Arrhenius expression obtained from the experimental results, k11⁄2k5k7−1⁄2=1013,0exp (−44000⁄RT) mol−1⁄2cc1⁄2 sec−1, is in harmony with those for k1, k5, and k7 available in the literature.
Surface Chemistry of the Polyamide Series. II. Effect of the Sarcosyl Residue on the Monolayer of Polyleucine
Authors: Yamashita Takuya , Isemura Toshizo 
Published: July 2006

Abstract
The effect of hydrogen bonding on the nature of poly-α-amino acid monolayers has been studied at air/water and oil/water interfaces with poly-l-leucine, poly-Dl-leucine, and the 3:1-, 1:1- and 1:3-copolymers of l-leucine with sarcosine.
Poly-l-leucine and poly-Dl-leucine have been found to give condensed monolayers on distillled water. The surface viscosity of poly-l-leucine was first detected at a larger area than its close-packed area. The strong interaction between polymer chains of polyleucine was suggested by these findings.
On the other hand, at both air/water and oil/water interfaces, the compressibility of the film is increased much more by the incorporation of the sarocosyl residue in the polymer chain. At the air/water interface, the films of 3:1- and 1:1- copolymers of l-leucine with sarcosine are of the expanded type, and the surface viscosities have first been detected at much smaller areas than their close-packed areas. These findings suggest that the interaction between polymer chains diminishes because of the decrease in the number of intermolecular hydrogen bonds.
The Oxidimetric Determination of Thioureas with Potassium Bromate
Authors: Singh Balwant , Verma Balbir Chand , Saran M S 
Published: July 2006

Abstract
Potassium bromate has been used as a redox reagent in the presence of potassium iodide for the visual and potentiometric determination of thiourea and its several alkyl and aryl derivatives in a sulphuric acid medium. In visual titrations, amylose, is used as a visual indicator, turning blue at the end-point. In the potentiometric method, a bright platinum wire is used as an oxidation-reduction electrode ; this is coupled with a saturated calomel electrode. The thioureas are oxidised to their corresponding disulphides with a single electron-change:
(Remark: Graphics omitted.)
This direct method is simple, accurate, instantaneous and widely applicable.
One of the present authors (B. C. V.) wishes to thank the Council of Scientific and Industrial Research, Rafi Marg, New Delhi, for the award of a Senior fellowship.
The Dielectric Properties of Some Alkyl Thiol
Authors: Kondo Seiichi 
Published: July 2006

Abstract
It has been concluded that both 2-methyl-2-propanethiol and 2-methyl-2-butanethiol are plastic crystals and that, in their highest temperature crystalline phases, molecules perform a rotational motion on the lattice sites. The intermolecular S–H…S hydrogen-bond, which might possibly exist in these phases, seems to be too weak to hinder the molecular rotation. Cyclohexanethiol does not seem to be a plastic crystal, probably because of its low molecular symmetry in the solid phase and its intermolecular hydrogen bond.
The Quenching Action of Benzoic Acid and Methyl Benzoate on the Fluorescence of Naphthalene Derivatives
Authors: Miwa Takuji , Koizumi Masao 
Published: July 2006

Abstract
1) The quenching action of benzoic acid (dimer) (BA) and methyl benzoate (MB) on the fluorescence of 2-naphthol (I), 2-naphthylamine (II), 2-naphthyl methyl ether (III) and N,N-dimethyl-2-naphthylamine (IV) in benzene and in cyclohexane has been studied.
2) MB has little or no quenching effect on the fluorescence of III and IV, whereas it shows a significant quenching action on I and II. The latter is due to the intermolecular hydrogen bonding between the fluorescer and the quencher (the H.B. mechanism).
3) BA shows quite a large quenching action on III and IV. All the results can be interpreted on the basis of a charge transfer mechanism for quenching (the C.T. mechanism).
4) The quenching action of BA is larger on I than on III, and larger on II than on IV, except for benzene solutions of II and IV, in which case the magnitudes are equal within the range of experimental error. These results has been discussed on the basis of a simultaneous occurrence of the C.T. and H.B. mechanisms.
Rearrangements of Tertiary Amine Oxides. XIII. The Reactions of p-Nitrobenzenesulfenyl Chloride with Pyridine-and α-Picoline N-Oxides
Authors: Oae Shigeru , Ikura Katuyata 
Published: July 2006

Abstract
In the reactions of both pyridine and α-picoline N-oxides with p-nitrobenzenesulfenyl chloride, the N–O bonds of the intermediate salts appear to cleave homolytically, and the p-nitrosulfinyl radical which arises from the homolytic cleavage of the N–O bond is considered to be so stable that only the secondary reaction products from the sulfinyl radical, and no heteroring-substituted products, were obtained.