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Despite the practice of using cylindrical specimens in a split-Hopkinson pressure bar (Kolsky bar) experiment, the use of non-cylindrical prismatic specimens is not uncommon. This is convenient when testing extra-soft materials like brain tissues, muscles, or samples that are brittle and cannot be machined to an exact cylindrical shape (like bone-samples). The use of a non-cylindrical sample with a flat surface also renders the specimen amenable to a two-dimensional image correlation algorithm. This research aims to show the feasibility of using non-cylindrical specimens in a Kolsky bar. For this, experiments were conducted with a model material for different model cross-sections at a nearly constant strain rate in the split-Hopkinson pressure bar. The findings suggest the use of a suitable characteristic cross-section dimension of the specimen to determine the critical slenderness ratio while selecting a non-cylindrical prismatic specimen. It has been shown that if the specimen design is governed by the suggested slenderness criterion, then there is no effect of specimen length or cross-sectional shape on the stress–strain curve of the material. Through the use of a computational code, the research also shows the effect of non-uniform axial stress distribution along the cross-section of the specimen, resulting due to specimen geometry. On quantification of the stress non-uniformity along the cross-section of the specimen, the findings indicate that the magnitude of the non-uniformity is both small and temporary.

By using various N-chloroalkylamines, the telomerization of ethylene with carbon tetrachloride was carried out in a stainless steel autoclave at 130 °C. It was found that the yields and the compositions of telomers varied widely according to the kinds and the structures of N-chloroalkylamines. When N-chloromonoalkylamines or N-chlorodialkylamines were used, the total yield of telomers was high compared with the case using N,N-dichloroalkylamines. In the presence of both N-chloromonoalkylamines and N-chlorodialky]amines, the total yield of telomers became higher and the greater part of the telomers was 1:1 adduct (n=1 telomer CCl3CH2CH2Cl) of ethylene with carbon tetrachloride.

Rhythmic crystallization behavior of methyl mesitylcarbamate from chloroform solutions under appropriate conditions was found. Effects of temperature, evaporation rate of solvent, and sample weight per area on this behavior are studied in detail, and the qualitative explanation based on the autocatalytic branching process is proposed.

A chemical system having a mnemonic function is constructed and its behavior is analyzed. The system consists of a subsystem having seven steady states and, under suitable conditions, it stays in a stable steady state or in an oscillating state depending on the initial state. Moreover, the system can show an additional oscillating state around the oscillating state and transitions between two different oscillating states occur by a little change in a certain parameter value(input), which is the characteristic point in this system. Therefore, a response behavior of the system to an input differs drastically depending on the states, i.e., oscillating or stationary. This property could be related to appearance of a mnemonic function. Moreover, it is demonstrated that the system could be linked with an excitable subsystem to show more clearly the mnemonic function proposed here.

The reactions of N-picolinoyl-S,S-tetramethylenesulfilimine (PS) and N-(trimethylammonio)picolinamidate (PA) with copper(II) chloride dihydrate in ethanol afforded complexes of the formula CuCl2(Y) and CuCl2(Y)2(Y=PA or PS). The structures of these complexes were examined by spectroscopic and magnetic methods, and it was found that all of them have mononuclear chelate structures. It was concluded that in CuCl2(PS), the ligand is coordinated through two nitrogen atoms, whereas in CuCl2(PS)2, the ligands are coordinated through carbonyl oxygens and nitrogens in pyridine rings. The structures of CuCl2(PA), CuCl2(PA)2, and CuCl(PA) are closely similar to each other and the possibility of coordination through ylidic nitrogens with large ionic contributions to the structures was strongly suggested. Several Cu(II) complexes with monodentate sulfilimines and aminimides were also prepared, and the structural analyses revealed that the nature of the coordination depends largely on the structure of the ylides.

The reactions of ethylene with chloroform initiated by alkylamine-ferrous chloride systems were examined in detail. Two main products, α,α,α-trichloroalkanes (I) and α,α,ω-trichloroalkanes (II), were obtained. Their composition was independent of the kind of amine but dependent upon the total carbon number of alkylamine. When amines having higher alkyl groups were used, the main product was α,α,ω-trichloropropane (II-1). When lower alkylamines were used, the main products were α,α,α-trichloroalkanes which contained considerable amounts of higher telomers. The results support the view that the reactions proceed according to the “caged free radical” process.

N-Aryl-a-chloro-a,a-diphenylacetimidoyl chlorides were prepared from Schiff bases and dichlorocarbene generated by use of the phase transfer catalyst. Treatment in sulfuric acid gave 3,3-diphenyl-2-indolinone derivatives. The synthetic route to 2-indolinone was found to give a higher overall yield than that by other methods. 2,2-Dichloro-1,3-diphenylaziridine gives a-chloro, a-acetoxy or a-hydroxy-a,a-diphenylacetanilide on treatment with sulfuric acid. Comparison of 2,2-dichloro-1,3-diphenylaziridine, 2,2-dichloro-1,3,3-triphenylaziridine and N-aryl-a-chloro-a,a-diphenylacetimidoyl chloride in their reactivities with sulfuric acid shows that the pathway of the reaction is governed by the character and number of substituents at the reaction center where carbonium ions are developed.

The reaction of 2,4,6-trimethylbenzonitrile N-oxide with various di- and tetrasubstituted p-benzoquinones and the structures of the products were studied. All of the tetrasubstituted quinones gave dioxazole derivatives through addition at the carbonyl site, whereas the disubstituted quinones gave dioxazoles or isoxazoline derivatives depending on the substituents. The reactivity of the quinone carbonyl toward the nitrile oxide varies with the substituents and with the substitution pattern; this phenomenon is discussed in terms of the resonance and inductive effects of the substituents.

Cycloaddition reaction of aromatic nitrile N-oxides, such as benzonitrile N-oxide, 2,4,6-trimethylbenzonitrile N-oxide, and 2,3,5,6-tetramethylbenzonitrile N-oxide, with tetrahalo-p-benzoquinones was studied. The reaction gave 1:1- and/or 2:1-adducts of a nitrile N-oxide and a tetrahalobenzoquinone according to the conditions, especially the mole ratios of each reactant. The 2:1-adducts are formed via1:1-adducts, each having two stereoisomers. The structures of these adducts were determined to be dioxazole derivatives formed by the addition of nitrile N-oxides to the carbonyl bonds of the tetrahalobenzoquinones.

A three-variable model system exhibiting complex oscillations was analyzed. Our analysis reveals a bifurcation structure of complex oscillations including chaotic oscillations. The bifurcation structure reproduces well the transition sequences of oscillatory states observed in the experiments of the Belousov–Zhabotinskii reaction and the chlorite oscillators. The transition sequence to chaotic oscillations in our model system shows period-doubling sequences. When the number Fis defined as a ratio of the number of large amplitude to the total number of oscillations per period in the complex oscillation, the number constitutes a monotonous, stepwise-increasing function of a control parameter. The sequence of the complex oscillations is described well by the Farey arithmetric. Also, the average flux of reaction was found to change abruptly at the bifurcation points of the complex oscillations.

The transition sequence from a complex oscillation or a combined complex oscillation to a chaotic oscillation of a three-variable model system of chemical reactions were studied through analyses of the bifurcation diagrams. Period-doubling sequences, discontinuous transitions between two different oscillation states, and intermittency-type pseudo-periodic oscillations were observed. A pseudo-periodic oscillation appears when a combined complex oscillation changes to a new oscillatory state under some transition conditions. By changing the conditions, the discontinuous transition becomes to occur, leading the hysteresis behavior of transition.

Sustained oscillation and birhythmicity have been observed when aqueous solutions of potassium permanganate, potassium nitrite, formic acid, and methanol were mixed in a continuous-flow stirred tank reactor. A detailed phase diagram is shown. This new oscillator is composed of non-halogen compounds and the first example of the nitrogen-based oscillator.

Two model systems exhibiting complicated oscillations were proposed and analyzed. One of them is a double oscillation system, which shows alternating oscillations of large and small amplitudes and the mechanism for appearance of the double oscillations is clarified. In the other system, either large or small amplitude oscillation appears depending on the parameter values, and the transition between the large and the small amplitude oscillation is very abrupt and sensitive to the change in external constraints.

The reduction of Methylene Blue (MB) with l-ascorbic acid to the corresponding leuco compound has been studied in aqueous surfactant solutions. The reduction was accelerated in the presence of cationic surfactant hexadecyltrimethylammonium bromide, but tetrabutylammonium bromide, which has no ability of micelle formation, does not show any effects on the reaction rate. The micellar effects are largely affected by pH of the medium, and the rate enhancing effects of the micelles are retarded by KCl. These results could be interpreted by the change in dissociation state of the substrate on the micelle surface and by the binding of the reaction product, leuco MB, to the micelles. The binding site of leuco MB was found to be outer core of the HTAB micelle by NMR. Similar results were obtained in the reduction of MB with l-cysteine, although the reduction did not proceed without the addition of cationic surfactant. The interaction between dissolved oxygen and the substrate in HTAB micellar solutions was also investigated.

In order to clarify the electron structure of carbonyl-stabilized phosphorus ylides, measurements of X-ray photoelectron spectroscopy (XPS) and combustion heat were performed. NMR and IR spectra were also measured as complementary methods. The results suggest that carbomethoxymethylenetriphenylphosphorane has a major contribution of polar bond (\overset+P—\overset−C) structure, whereas benzoylmethylenetriphenylphosphoranes have a larger contribution of covalent bond (P=C). A dπ–pπ interaction in the P–C bond was interpreted for XPS and NMR. The data for heat of combustion suggest that a large contribution of the polar bond structure brings about stabilization of the ylide molecule. These results show that XPS and combustion heat measurements are useful means for the analysis of ylide bonding.

N-Chloroalkylamines initiate the telomerization of ethylene with chloroform to give α,α,α-trichloroalkanes CCl3(C2H4)nH(I), which are the same products as those obtained by peroxide-initiated reactions. The N-chloro-alkylamine–iron and N-chloroalkylamine–ferrous chloride systems also initiate the reaction of ethylene with chloroform to afford α,α,ω-trichloroalkanes CHCl2(C2H4)nCl (II) as the main product, and a small amount of I along with other teJomers. The rate of the reaction and the composition of the products vary widely with the kind of N-chloroalkylamine. The reaction mechanism was discussed, a “caged radical” mechanism being proposed for the N-chloroalkylamine-ferrous chloride system.

The properties of the reversed micelles of dodecylammonium propionate (DAP) and of solubilized water were examined for systems with hexane, chloroform and benzene as a nonpolar component. The aggregation number of DAP, the conductivity, the heat of solution of water, IR and NMR spectra, and near infrared spectra of solubilized water were measured. From the results the properties of the reversed micellar system were analyzed, the following conclusion being obtained. The aggregation state of DAP is scarcely affected by the addition of water. Water is first dispersed in the nonpolar organic phase, and then solubilized in the cores of the reversed micelles. The former is free or weakly bonded water, while the latter is bonded water like that in the bulk phase. The catalytic effect of DAP reversed micellar system is discussed.

The infrared spectra of the solutions of dodecylammonium propionate (DAP), hexadecyltrimethylammonium bromide (HTAB), and sodium bis(2-ethylhexyl) 2-sulfonatosuccinate (SBSS) in organic solvents were recorded in Fourier transform mode. Difference concentration spectra of DAP in dichloromethane exhibited the change in the stretching bands of the carboxylate ions, which was attributed to the formation of micellar aggregates. Difference hydration spectra were also obtained for water-containing DAP–CH2Cl2, HTAB–CH2Cl2, and SBSS–benzene systems, and the spectra in the region of 3000–3700 cm-1and 1600–1650 cm-1revealed the existence of free water dispersed in the organic phase and water bound to the micelles. The diffreence spectra also revealed the change in the bands of DAP and SBSS due to hydration of the ionic head groups. The absorption frequency of the O–H stretching bands was discussed in terms of the water-surfactant-interaction.

The reactions of N-picolinoyl-S,S-tetramethylenesulrilimine and N-trimethylammoniopicolinamidate with dichlorobis(benzonitrile)palladium(II) and dipotassium tetrachloroplatinate(II) afforded chelate complexes of formula MCl2[Ylide]. The structures of the complexes were examined by IR and NMR spectroscopy, and determined as mononuclear complexes with ligands coordinated through two nitrogen atoms. A reverse relationship between pKavalues of the ylides and C=O stretching band frequency shifts on complex formation was found, and the nature of the coordination viaylidic nitrogen was discussed in terms of s- and p-character of the ligands in the chelate complexes and several related bis-ylide complexes.

Solvolytic ring-opening reactions of gem-dichloroaziridines in the presence of sulfuric acid were investigated. The reaction products from 1-aryl-2,2-dichloro-3-phenylaziridines varied with the kind of substituent at 3-position of the aziridine ring. 2,2-Dichloro-1,3-diphenylaziridine gave a-chloro-a-phenylacetanilide, 2,2-dichloro-3-methyl-3-phenyl-1-(m-tolyl)aziridine gave N-(m-tolyl)atropamide and 2,2-dichloro-1,3,3-triphenylaziridine gave 3,3-diphenyloxindole. 1-Benzyl-2,2-dichloro-3,3-diphenylaziridine and 2,2-dichloro-1 -phenethyl-3,3-diphenylaziridine gave 4,4-diphenyl-1,2,3,4-tetrahydroisoquinoline-3-one and 1,1-diphenyl-1,2,3,4,5-pentahydro-3-benzazepine-2-one, respectively. It was found that the substituent on C3-carbon determines the mode of reaction.

The iodination reactions of ketones in the reversed micellar systems of dodecylammonium propionate (DAP) in hexane were studied at 25.0 °C in relation to the enzymatic function of aldolase or enolase. The reaction rate in the DAP reversed micellar system is 106–107times greater than that in the system without DAP, 100 times greater even in comparison with that in DAP aqueous system at pH 6.8. As in the ammonium ion catalyzed reaction in aqueous media, the reaction in the presence of DAP proceeds viaketimine formation between ammonium groups of DAP and acetone and subsequent enolization of ketimine to enamine, which reacts very rapidly with iodine. The catalytic effect of DAP reversed micellar system in each reaction step was discussed. Further, this reversed micellar system shows a marked selectivity for acetone as compared with higher analogs.

The nonenzymatic hydrolysis of adenosine 5'-triphosphate (ATP) in micellar and reversed micellar system was examined as an approach to elucidate the function of ATPase. In aqueous micellar systems an anionic surfactant does not affect the hydrolysis rate, but a cationic surfactant, cetyltrimethylammonium bromide(CTAB), retards the hydrolysis. This deceleration effect is interpreted to be owing to the pH change or accumulation of hydroxide ions at the cationic micellar-water interface which serves as reaction site. In the reversed micellar system where aqueous ATP phase is solubilized in n-hexane by dodecylammonium propionate(DAP), the hydrolysis rate of ATP is enhanced by several times as compared with that in an aqueous system. Addition of Mg2+or Ca2+enhances the hydrolysis rate markedly only in the DAP reversed micellar system. The catalytic effect of the DAP reversed micellar system is discussed with respect to the polarity of water phase solubilized in the core of reversed micelles.

The electrolytic polymerization of acrylonitrile in constant current was examined by using several supporting electrolytes and the reaction mechanism was discussed. An explanation was given for the anomaly characteristic of the cathodic polymerization using sodium nitrate as a supporting electrolyte, which was reported by Funt. It was revealed that the polymerization is initiated by a radical mechanism at the anode and by an anionic mechanism at the cathode. The termination reaction of the anionic polymerization was analyzed by a kinetic approach and from the structural information of polymers obtained.

(1) A method for measuring the dynamic visco-elasticity of liquid by the torsional oscillation is described.(2) The visco-elastic oils produced by the thermal polymerization of linseed oil to various, degrees were studied by this rheometer.(3) The amplitude effect of the dynamic properties was negligible ; so that these materials are supposed to be linear in their visco-elastic behavior.(4) The dynamic visco-elasticity of these oils was measured in the very low frequency region (period : 10 seconds-5 minutes).(5) The temperature dependence of the dynamic viscosity was discussed.(6) Weissenberg effect of these oils was tested in a qualitative way.

Methyl methacrylate polymerized in the presence of a surface active agent in an aqueous system without any ordinary initiators. Anionic surface active agents, such as sodium tetrapropylenebenzenesulfonate and sodium 2-dodecylbenzenesulfonate, markedly effected the polymerization of methyl methacrylate in the presence of water. The polymerization was inhibited by adding hydroquinone to the reaction system and was also affected adversely by oxygen. Water as a reaction medium was found to be indispensable. The polymerization in organic solvents afforded hardly any polymeric products.

The anionic telomerizations of styrene with n-butylamine, s-butylamine, t-butylamine and isobutylamine catalyzed by sodium metal were investigated. The structures of the products were discussed by the NMR spectra obtained in carbon tetrachloride and identified to be N-butyl-2-phenylethylamines and N-butyldi(2-phenylethyl)amines. The general reaction scheme was proposed and interpreted with the concept of the anionic telomerization, where amine acts as a telogen and styrene as a taxogen.

Telomerization of vinyl chloride with carbon tetrachloride was investigated in reaction systems containing amines and cupric chloride. The yield of telomers CCl3(CH2CHCl)nCl and the content of the telomer with n=1 were high when aliphatic amines with relatively long chains were used. An increase in basicity of amines raised the yield of telomers. When bifunctional amines such as diamines and alkanolamines were used, the yield of telomers was low and the content of higher telomers was high. The effect of added solvents on the yield of telomers was not so remarkable and an increase in the dielectric constant of solvents decreased the yields. The results were examined on the basis of Asscher-Vofsi mechanism, but could not be explained satisfactorily. A partly modified scheme was proposed for the radical addition in the cage complex stabilized with amine.

The thixotropic behavior is discussed on the basis of the thermodynamics of irreversible processes. The fundamental equations are given for the thixotropic fluids by accepting the concept that the internal structure of the system is destroyed by the applied forces, and the general phenomenological equations are written for all the processes occurring in this system. The process by which the thixotropic recovery takes place is non-stationary. A method of specifying this process is proposed by introducing the concept of a fictitious pressure tensor; the data on a rubber latex suspension given by Mooney is analyzed by this method.

The rectifying properties of liquid junctions of polyelectrolyte solutions are examined and discussed. In the case of liquid junctions between aqueous solutions of poly(styrene-sulfonic acid) and poly(2-vinyl-N-n-butylpyridinium hydroxide), the rectification effects greatly depend on the concentrations of the polyelectrolytes and on the frequencies of the voltages applied, that is, rectification effects can not be found when the concentrations of polyelectrolytes are lower than 0.68×10−3equivalents per liter and when the frequencies of the alternating voltages are higher than 200 cps. The mechanism of rectification can be explained to some extent by a semiconductor analogy. In the case of liquid junctions between poly(styrene-sulfonic acid) and poly(2-vinyl-N-n-butylpyridinium bromide), the static current versusvoltage curves have strong hysteresis loops. The rectification effects can be slightly observed when alternating voltages with frequencies lower than 100 cps are applied. In this case, however, the mechanism of rectification can not be explained by the semiconductor analogy.

Styrene polymerized in the presence of sodium tetrapropylenebenzenesulfonate in an aqueous system without any ordinary initiators. The rate of the polymerization was dependent on the concentration of the surfactant and on the initial monomer concentration. The apparent activation energy of the polymerization was about 13.9 kcal/mol. The polymerization was inhibited by adding hydroquinone to the reaction system.

The electrolytic reduction of naphthalene was carried out in various alcohol-hexamethylphosphoramide (HMPA) systems in the presence of lithium chloride. The reduction of naphthalene proceeds effectively at relatively low cathode potentials in the presence of HMPA; the composition of the products varies with the changes in the reduction potential, the kind of alcohols, and the concentration of HMPA. The dark blue color is observed at the cathode during the electrolysis in HMPA solutions in either the presence or the absence of ethanol. It is suggested that the color reflects the generation of solvated electrons, and that reduction of naphthalene is caused not through a direct electron-transfer from the cathode, but through a reaction with solvated electrons as the reductive agent.

The anionic telomerizations of styrene with some secondary amines catalyzed by sodium metal were investigated. In this reaction a secondary amine was used as a telogen and styrene as a taxogen. Three telomers, i. e. N,N-disubstituted 2-phenylethylamine, N,N-disubstituted 2,4-diphenylbutylamine and N,N-disubstituted 2,4,6-triphenylhexylamine were separated from the mixture of the produced telomers under vacuum distillation. Proton NMR spectra of these telomers in carbon tetrachloride were consistent with the expected structural formulas. The reaction scheme was proposed to explain the formation of telomers.

The rectifying properties of the combined systems of two crystals, one being doped with a proton donor (poly(styrene sulfonic acid) or hydrogen fluoride) and the other being doped with a proton acceptor (poly(2-vinyl-N-n-butylpyridinium bromide), poly(2-vinyl-N-n-butylpyridinium hydroxide) or lithium hydroxide) are examined and discussed. In the case of the combination of the ices doped with poly(styrene sulfonic acid) and poly(2-vinyl-N-n-butylpyridinium hydroxide) or poly(2-vinyl-N-n-butylpyridinium bromide), the current versusvoltage curves have the hysteresis loops and the rectification ratio defined as the ratio of the forward current to the backward current is low. The dynamic rectification effect is slightly observed. In the case of the combination of the ices doped with lithium hydroxide and hydrogen fluoride, the rectification ratios exceed 100 and the rectification mechanism is presumed to be the same as in the system of the aqueous solutions. The dynamic characteristics depend on the frequencies; the rectification phenomena are not observed when the alternating voltages with frequencies higher than 30 kc are applied.

The anionic telomerizations of styrene with some aromatic amines catalyzed by sodium metal were investigated. o-Toluidine, m-toluidine, p-toluidine, 2,4-xylidine, 2,5-xylidine and 3,4-xylidine were used as the aromatic amines. Each amine reacted with styrene to give an addition product, which was identified as N-substituted 2-phenylethylamine. Though both α-hydrogen atoms on α-carbon atoms and hydrogen atoms attached to nitrogen atoms of the aromatic amines are weakly acidic, only the latter hydrogen atoms were detached by alkali species under the present experimental conditions. The formations of the products were discussed from the standpoint of anionic telomerization.

The polymerization of methyl methacrylate in the presence of sodium tetrapropylenebenzenesulfonate(ABS) in an aqueous system without any ordinary initiators was examined kinetically. The rate of polymerization of methyl methacrylate is dependent on the initial concentrations of methyl methacrylate and ABS, and expressed by the equation:Rp∝[ABS]0.37[MMA]0.32The apparent activation energy of the polymerization is about 3 kcal/mol. It was confirmed by electron microscopic observation that the number of polymer molecules is in the same order as that of the micelle particles in the polymerization system.

The electrolytic reductive dimerization of acrylonitrile was investigated extensively especially in order to obtain some mechanistic information. The essential point of this reaction exists in the selective formation of adiponitrile under relatively wide conditions and this cannot be explained by a normal kinetic treatment based on the reaction scheme which has been accepted as probable. The heterogenuity in acrylonitrile concentration in the reaction system is assumed and the kinetic formulas are modified. This treatment explains the experimental results very satisfactorily. In order to confirm this mechanistic scheme, the effects of temperature, pH and solvents on the yield of reaction products were examined. All the results are consistent with the proposed mechanism.

The polycondensation reactions of ferrocene with terephthaloyl and adipoyl chloride were investigated in the presence of AlCl3, ZnCl2, or FeCl3as the catalyst and in dichloromethane, n-hexane, carbon tetrachloride, or dioxane as the solvent. With terephthaloyl chloride, the highest polymer yield was obtained when AlCl3in n-hexane was used, and the product was mainly of a polyketone structure. The polycondensation with adipoyl chloride afforded the most satisfactory result when ferrocene was treated in liquid adipoyl chloride with neither catalyst nor solvent, and a product with the expected structure was obtained. The average molecular weights of the products are in the range of 3000–7000. Polymers obtained by polycondensation with terephthaloyl and succinyl chloride are paramagnetic and show the temperature dependence characteristic of semi-conductivity.

The ion-exchange behavior of the acidic and the basic amino acids was described and discussed. The maximum uptake of amino acids takes place in the pH range close to the iso-electric points and the pH effect is more remarkable and more characteristic, in comparison with the case of neutral amino acids. Theoretical treatment on ion-exchange equilibria, which takes account of the dissociation equilibria of amino acids, explains well the experimental results and the selectivity coefficients were estimated herefrom.

Some observations are presented on the aggregation behavior of the ion-exchange resin particles. On mixing the hydrogen-form cation-exchange resin particles with the hydro-xyl-form anion-exchange resin particles, remarkable aggregation takes place. It seems that this aggregation is due to the electrostatic attraction force exerted between resin particles. This is supported by the results that the aggregation is destroyed by addition of salts and that the agglomerates are not formed in non-polar medium in the complete absence of water. Moreover, it was demonstrated that the variation of the size ratio of particles influences markedly the aggregation behavior. A simple explanation is given for such a coagulation phenomena.

The ion-exchange behavior of three kinds of neutral amino acids was examined and the following results were obtained.1) The ion-exchange behavior of amino acids can be explained when the dissociation equilibrium of amino acids in the solution was taken into account.2) The maximum adsorption of neutral amino acids on the ion-exchange resins takes place in a rather broad pH range at the iso-electric point.3) The neutral amino acids are adsorbed more extensively on cation-exchangers than on anion-exchangers. Glycine is adsorbed most extensively and leucine is more adsorbed than alanine.

The electrolytic rectification effect has been observed in a double-membrane system. The static and dynamic current-voltage characteristics have been measured, and it has been demonstrated that the mechanism of the rectification similar to that of the p-n semiconductor junction holds true for this system. Reasonable values have been estimated for the characteristic parameters, although there are many discrepancies requiring further examination.

Atmospheric rivers (ARs) traveling thousands of kilometers over arid North Africa could interact with the highlands of the Near East (NE), and thus affect the region's hydrometeorology and water resources. Here, we use a state‐of‐the‐art AR tracking database, and reanalysis and observational datasets to investigate the climatology (1979–2017) and influences of these ARs in snowmelt season (March–April). The Red Sea and northeast Africa are found to be the major source regions of these ARs, which are typically associated with the eastern Mediterranean trough positioned over the Balkan Peninsula and a blocking anticyclone over the NE‐Caspian region, triggering southwesterly air flow toward the NE's highlands. Approximately 8% of the ARs are relatively strong (integrated water vapor transport >∼275 kg m−1s−1). AR days exhibit enhanced precipitation over the crescent‐shaped orography of the NE region. Mean AR days indicate wetter (up to + 2 mm day−1) and warmer (up to + 1.5°C) conditions than all‐day climatology. On AR days, while snowpack tends to decrease (up to 30%) in the Zagros Mountains, it can show decreases or increases in the Taurus Mountains depending largely on elevation. A further analysis with the observations and reanalysis indicates that extreme ARs coinciding with large scale sensible heat transport can significantly increase the daily discharges. These results suggest that ARs can have notable impacts on the hydrometeorology and water resources of the region, particularly of lowland Mesopotamia, a region that is famous with great floods in the ancient narratives. Atmospheric rivers (ARs) are important components of the global water cycle as they are responsible for over 90% of the poleward moisture transport at middle to high latitudes. ARs mostly prevail over the oceans and primarily landfall on the western coasts of the midlatitude continents as a result of westerly flow of the midlatitudes. Apart from the large ocean basins, certain ARs can develop and propagate over continents, which has received less scientific attention. In this respect, this study aims to show how overland African ARs developing in the snowmelt season can influence the Near East's highlands, which are essential for satisfying the water need of lowland areas of Mesopotamia that are potentially at risk of water scarcity and conflicts. We show that mean AR days lead to wetter and warmer conditions than a typical day in the snowmelt season. On AR days, while snowpack tends to decrease (up to 30%) in the Zagros Mountains, it can show decreases or increases in the Taurus Mountains depending largely on elevation. We emphasize that the poleward warm air advection and moisture transport toward the Near East within ARs can have profound impacts on the water resources of the region. African atmospheric rivers (ARs) can transport tropical humid air towards the Near East in the snowmelt seasonThe region is wetter and warmer on AR days compared to all‐day climatology, causing changes in snowpack depending on elevationExtreme ARs accompanied by large scale sensible heat transport cause significant rises in river discharges in the region African atmospheric rivers (ARs) can transport tropical humid air towards the Near East in the snowmelt season The region is wetter and warmer on AR days compared to all‐day climatology, causing changes in snowpack depending on elevation Extreme ARs accompanied by large scale sensible heat transport cause significant rises in river discharges in the region

Silent pituitary adenomas are a group of tumors showing heterogenous morphological features with no hormonal function observed clinically. To date no explanation has been provided as to why these tumors remain ''silent''. We report a case of a silent macroadenoma with both growth hormone (GH) and thyroid stimulating hormone (TSH) staining and secretion but with no clinical manifestations, in particular, the absence of features of acromegaly or hyperthyroidism. The relevant literature is reviewed.

The kinetic parameters of the dehydration of Zeise’s salt hydrates, K[PtCl3(olefin)]·H2O, (olefin; CH2=CH2, CH3CH=CH2, C2H5CH=CH2, n-C3H7CH=CH2and n-C4H9CH=CH2) and the thermal decomposition of Zeise’s dimers were determined by using DTA and TG. By comparing the kinetic parameters with the data of IR and the enthalpy change of dehydration, it was shown that the important factor in determining the kinetic behavior of the dehydration is an extent of deformation of lattice at the transition state. Similarly, it was suggested that the bulkiness of ligand olefin is an important factor in governing the kinetics of the thermal decomposition reactions.

The base decomposition of ethyl p-nitrophenylsulfonyloxycarbamate in organic-aqueous two-phase systems in the presence of cis- or trans-4-methyl-2-pentene and quaternary ammonium or phosphonium halides afforded both stereospecific and nonstereospecific addition products of ethoxycarbonylnitrene. The electronic state of the nitrene was analyzed on the basis of Skell’s hypothesis.

The nature of bondings in aryl-nickel complexes has been clarified by means of X-ray photoelectron spectroscopy (XPS). Pi bonding between nickel and aryl ligand seem to be of little importance. Ni–Cl bondings are of partially ionic character. A correlation between stereochemical structure and satellites has been discussed. It is suggested that the aryl-nickel complexes examined have diamagnetic square-planar structures. Measurements of solid-state susceptibilities support this view.

Using a twin-type calorimeter, the enthalpy changes of solutions and reactions with aqueous KCN solution of Zeise’s salts, K[PtCl3(olefin)], were measured. As ligand olefins, ethylene, propylene, 1-butene, 1-pentene, and 1-hexene were employed. It was estimated from a thermochemical analysis that the order of strength of platinum-olefin bonding is as follows; K[PtCl3(C3H6)]\gtrsimK[PtCl3(C3H6)]\gtrsimK[PtCl3(1-C6H12)]\gtrsimK[PtCl3(1-C4H8)]\gtrsimK[PtCl3(1-C5H10)]. This order was compared with the data of infrared spectra and both the results coincide with each other.

The flow properties of the suspensions of ion-exchange resin particles, the highly-crosslinked polyelectrolyte gel particles, were examined, especially in relation to their charged state. The steady viscosities and the dynamic viscoelasticities of these suspensions were measured, and the results were interpreted in terms of the dispersion state of the suspended particles. The flow system of the highly-charged particles, such as Na-form resin particles, exhibits a high viscoelasticity and is in a well-dispersed state. On the contrary, the flow system of the lower-charged particles, such as Ba-form particles, is not viscoelastic, but viscous and dilatant. This behavior may be attributed to the variation in the electrical double layers around the suspended particles.