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The ultrasonic absorption has been measured in aqueous solutions of Ni(II) complexes of glycine, β-alanine, 4-aminobutyric acid, and 6-aminohexanoic acid. The relaxation absorption could not be ascribed to one of the steps of the ordinary step-by-step complex formation mechanism. Kinetic data were obtained as functions of the initial concentrations of Ni(II) and amino acids, the pH, and the temperature. The relaxation absorption was attributed to the formation-breaking equilibrium of an intramolecular hydrogen bond due to the carboxylato group of amino acid coordinated to the Ni(II) ion. The rate constant of the hydrogen bond-breaking process has been obtained. The relationship between the relaxation parameters and the acid dissociation constant of the carboxyl group of the amino acid ligands is discussed with reference to the analogous result for the carboxylato ligands reported previously. Supplementary work is also carried out for Ni(II)-aspartato and glutamato complexes.

The binding isotherm of sodium dodecyl sulfate to amylose was potentiometrically investigated by using amyloses of various degrees of polymerization from 32 to 1100. From the Scatchard plots, the binding was found to be cooperative for the amyloses of DP≥76 and Langmuir type for those of DP≤57. By analogous experiments using a series of sodium alkyl sulfates, it was clarified that (1) eight carbon atoms of surfactant are required for the complexation and (2) more than twelve carbon atoms of surfactant are required for the cooperative binding. Thus, the amylose has an interrupted helical structure in solution and the cooperativity arises from the hydrophobic interaction between the surfactants included partly in the helic of amylose.

Concentration-jump kinetic studies of the aqueous poly(acrylic acid)–copper(II) system reveal the presence of a relaxation phenomenon in the time range of 102 ms. Kinetic data under various pH’s and compositions, together with the potentiometric results, indicate that this relaxation effect is due to the following complex-formation reaction:CuL2+L22−\oversetk2\undersetk−2\ightleftharpoonsCu(L2)22−,where L22− is a coordination unit consisting of two adjacent carboxylato side groups on the polymer chain. The specific features of the pH dependence of the τ−1 value are discussed in relation to the degree of dissociation of the carboxyl groups. The rate and stability constants of the reaction are determined to be: k2=5.6×103 M−1 s−1 (1 M=1 mol dm−3), k−2=0.7 s−1, and K2 (=k2⁄k−2)=7.9×103, at pH 7.0, I≈0, and 25 °C. The overall complex-formation mechanism, involving the very rapid formation of CuL2, is discussed.

This paper deals with the fatigue crack growth behavior of an anisotropic rolled steel plate (SB56M). Two groups of materials were prepared by annealing and spheroidizing treatments, so that the effects of the laminated structure and the mechanical fibering of inclusion, both of which were produced by rolling, could be separated. The fatigue crack growth behavior in various anisotropy directions was examined microscopically as well as macroscopically. The crack growth behavior was much more anisotropic with the annealed material than with the spheroidized material. It is concluded with this class of the steel plate investigated that the anisotropy in the behavior of crack growth on the microscopic and macroscopic levels was primarily affected and controlled by the laminate structure, while the inclusions gave a secondary effect on the anisotropy of crack growth.

This paper deals with the stress concentration analysis of 60°V-shaped or a partially-circular double edge notches in an infinite strip under remote tension. The stress field induced by a point force in a semi-infinite plate is used to solve these problems. The present results for semi-circular notch are in close agreement with other reports. The results calculated on the 60°V-shaped notches show that the Neuber formula gives an underestimated stress concentration factor in about 11% for a wide range of notch depth. However, in case of blunt notches, the Neuber solution of deep hyperbolic notches still gives a sufficient accuracy in engineering use. In addition, the stress concentration factors of 60°V-shaped notches are also represented by diagrams for wide use.

An ultrasonic absorption study has been carried out on aqueous acidic solutions of mercury(II) acetate. The absorption data shows a single-relaxation phenomenon in the frequency range of 15–95 MHz. On the other hand, the results of the pH measurement indicate that the only mecury(II) acetate complexes conceivable in solution are of the HgL+ and HgL2 forms (L− denotes the acetate ion); the succesive formation constants of these complexes, together with the mercury(II) hydrolysis constants, are also determined. The equilibrium constants reported are: 2.1×103 for K1, 4.9×103 for K2, 6×10−4 for Kh1, and 1.0×10−3 for Kh2, at 30 °C and I=1. On the basis of the above results, the ultrasonic relaxation absorption is ascribed to the complex formation reaction: HgL++L−\leftrightharpoonsHgL2. The rate constants and the volume change of this reaction are determined to be: kfo=7.8×109 M−1 s−1, kbo=1.6×106 s−1, and ΔV=18 cm3 mol−1, at 30 °C.

The microcrack growth law-oriented approach developed in a previous paper is applied to examine the fatigue strength and mechanism of 200 mm and 100 mm thick forged steel plates. Low-cycle fatigue tests are conducted on specimens sliced in the transverse (T) and thickness (S) directions of the plates. Through continual observation of the fatigue process, the effect of elongated inclusions on microcrack initiation and propagation behaviors is elucidated. The fatigue life is shorter in the S than in the T direction. The fatigue lives in both directions are evaluated on the basis of the microcrack propagation law. The elongated inclusions hardly affect the fatigue process in the T direction, while they show a strong influence in the S direction. The fatigue process is dominated by a monotonous growth of a leading crack in the T direction. On the contrary, the leading crack growth in the S direction is governed by a joining of subcracks.

Nominal stress-controlled low-cycle fatigue life under imposed mean stress is affected by elongation or contraction due to cyclic stress-induced creep. Therefore, the effect of mean stress was examined by a microcomputer-assisted testing device which provides true stress controlled loading. Through investigation of a medium carbon steel (S45C), the following results, were obtained:(1) Cyclic plastic strain amplitude at the steady cyclic stress-strain state decreased with an increase of the imposed tensile mean stress.(2) The cyclic stress-induced creep proceeded so far as the mean stress was imposed. The increase in axial cyclic creep strain per cycle was proportional to the nth power of the maximum cyclic stress.(3) For the same cyclic stress amplitude, the application of tensile or compressive mean stress prolonged the fatigue life as compared with the fully reversed stressing.(4) A modified Manson-Coffin relation including such two parameters as the cyclic stress amplitude and the mean stress was proposed for evaluating the fatigue strength under cyclic stress-induced creep condition.

A pressure-shock apparatus applicable for the kinetic studies of rapid reactions in solution was constructed and used to study Co(II)–carboxylate complex-formation reactions. The chelate complex-formation reaction was interpreted in terms of a step-by-step mechanism, and the rate constants were obtained. The chelate-ring closing-and-opening process was revealed to be the rate-determining step.

Hydrolyse de methyl-1 heptylamine, tetramethyl-1,1,3,3 butylamine, phenyl-4 butylamine, phenyl-3propylamine phenethylamine et benzylamine en presence de micelles de laurylsulfate de Na

Serumα 1 phenotypes were determined by polyacrylamide gel slab isoelectric focusing in a sample from 1,271 unrelated healthy Japanese living in Tokyo. Three common Pi M subtypes (M1M1, M1M2 and M2M2) were found, and the allele frequencies estimated (Pi M1=0.83,Pi M2=0.17) were found to be similar to those observed in the European populations. A large χ2 value, however, may indicate the presence of further microheterogeneity among Pi M subtypes. In contrast with Pi M subtypes, rare variants were found only in 0.55% of the samples examined, and no Z gene was detected. A new fast variant ofα 1 named Pi ETokyo is reported.

Complex formation in the ternary system of amylose (degree of polymerization, DP, 1100), SDS, and iodine was studied statically by spectrophotometry and amperometric titration and kinetically by the pressure-jump method. It was clarified that (1) iodine (I3−) to some extent binds to amylose saturated with SDS to form an inclusion complex (ASI system); (2) the binding of SDS apparently transforms amylose of DP 1100 to that of much lower DP (less than 60) from the viewpoint of iodine binding; and (3) iodine binds to sites unoccupied by SDS in the center of the helical segment of amylose. Pressure-jump relaxation phenomenon was not observed in solutions in which iodine was dissolved prior to SDS (AIS system), but it was observed in the ASI system; it is ascribed to the association and dissociation of three molecules of iodine in the center of the amylose helix. Comparison of the rate constants in the ASI system with those in the amylose (DP 32) and iodine system indicates that iodine runs to and from the helical segment of amylose perpendicularly to the axial plane in the former, while it runs horizontally in the latter. We discuss the order of ligand mixing on the resulting structure of the ternary complexes of amylose, SDS, and iodine.

The gel-liquid crystal phase transition of the bilayer membrane of dioctadecyldimethylammonium bromide was studied statically by monitoring the turbidity, the volume, the conductivity, and the sound velocity of the aqueous solution. With decrease of the temperature, these physical properties changed very steeply at 40-39°C and the phase transition temperature T m was determined to be 39.5°C. When the temperature was raised, a hysterisis was observed and the value of T m was about 3°K higher. A decrease of the volume and increases of the conductivity and the compressibility observed at the phase transition from the liquid crystal to the gel indicated that a phase transition accompanies the dissociation of the counterion from the bilayer membrane. The kinetic studies by the pressure-jump method and the ultrasonic absorption method showed that the phase transition is composed by at least two processes, one is a nucleation and annihilation process with the time constant of the order of 10 −2 sec and the other is a growth and shrinking process on the order of 10 −9 sec. Both relaxation phenomena have maximum relaxation time and amplitude at around T m , which indicates that both processes are cooperative. Static and kinetic studies were also performed for the bilayer membranes of dimethyloctadecyldodecylammonium bromide and didodecyldimethylammonium bromide, but no evidence of the phase transition was observed. The pressure-jump relaxation observed in the time ranges of 10 −2 and 10 −3 sec, respectively, was ascribed to the monomer association and dissociation to and from the bilayer membrane.

Both static and kinetic investigations have been performed on the interaction of calf thymus DNA with Acridine Orange (AO). The binding isotherm obtained spectrophotometrically was analyzed by a site exclusion theory and revealed the presence of two binding modes of dye molecule corresponding to intercalation and dimerization on DNA. In the kinetic experiments focusing on the intercalation mode by the temperature-jump technique, three relaxations were observed. From the analyses of both the relaxation time and amplitude, the two fast relaxations were ascribed to parallel binding reactions including a bimolecular pathway for direct transfer of dye molecule on the polymer and the slow relaxation was attributable to a conformational change of DNA molecules. The binding parameters kinetically obtained suggest that 80% of bound AO is in intercalated form and the remainder is in partially intercalated one as an external bound form.

We describe a genetic polymorphism of cytosol polypeptide with mol. wt. of 38,000 detected in phytohemagglutinin (PHA)-stimulated peripheral blood lymphocytes by two-dimensional gel electrophoresis. Three different electrophoretic phenotypes (type 1-1, 2-1, 2-2) of the polypeptide have been identified in a Japanese population. Family and population studies indicate that three phenotypes are determined by two common alleles at a single autosomal locus. Since the polypeptide is mainly present in cytosol of cells, we propose that the polypeptide be temporarily designated as cytosol polypeptide with mol. wt. of 38,000 (CP 38) and that the gene for CP 38 be designated as CP 38. The gene frequencies of two common alleles (CP 381 and CP 382) are 0.899 and 0.101, respectively, in a Japanese population. The data on gel filtration of cytosol proteins on a Sephadex G-100 column suggest that CP 38 exists as a dimer in the cytosol. CP 38 was observed in the wide range of different cells, including B-lymphoblastoid cells, adult skin fibroblasts, HeLa cells, and erythrocytes. In 11 out of 72 individuals, the phenotypes of CP 38 were different from those of adenosine deaminase which is similar to CP 38 in subunit size, cell distribution, and allele frequencies. These data indicate that CP 38 is a new polymorphic polypeptide encoded by an autosomal locus.

The hydrodynamic behavior of amylose with and without sodium dodecyl sulfate (SDS) has been examined by viscosity measurements. Two distinct viscosity phenomena have been observed by complexation; one is the increase at the first stage of binding of SDS, which disappears by an addition of salt, and the other is the subsequent decrease in the region of further binding of SDS. These results are interpreted by an idea that the expansion of the complex occurs by an electrostatic repulsion of the bound SDS molecules and the contraction of the complex by a hydrophobic interaction of cooperatively bound SDS molecules. This idea was confirmed further by experiments using amyloses of different length and homologous surfactants of SDS.

Temperature-jump relaxation studies have been carried out on aqueous nickel(II)–L-glutamic acid solutions. The observed relaxation phenomenon is ascribed to the successive complex formation reactions:Ni2++L2− \oversetk1\undersetk-1\ightleftharpoons NiL,NiL+L2− \oversetk2\undersetk-2\ightleftharpoons NiL22−,NiL22−+L2− \oversetk3\undersetk-3\ightleftharpoons NiL34−,where L2− denotes a glutamate ion. The rate constants are: 2.0×104, 1.1×104, and 9.2×103 M−1 s−1 (1 M=1 mol dm−3) for k1, k2, and k3, and 0.048, 0.69, and 27 s−1 for k−1, k−2, and k−3, respectively, at 25 °C and I=0.1. The rate-determining step of the complex formation reactions, which follows the initial formation of ion-pairs, is the dissociation of a water molecule from the inner hydration sphere of the nickel; the glutamate ion acts as a bidentate ligand forming a five-membered chelate ring in the complexes.

Haemolysate samples from 414 unrelated Japanese living in Tokyo were examined for GLO phenotypes by starch gel electrophoresis using a tris-citrate-borate-LiOH buffer system, pH 7.4. Three phenotypes were found which were classified as GLO 1 (2; 0.48%) GLO 2-1 (40; 9.66%) and GLO 2 (372; 89.86%). The corresponding gene frequency forGLO1 was 0.0531 and that forGLO2 was 0.9469. It was confirmed that theGLO1 frequency of Japanese is much lower than the values previously reported for Caucasians and Africans.

Etude de la relaxation dans des solutions d'acide benzoique (et ses derives) en presence du chlorure de dodecylammonium. La relaxation est attribuee a la protolyse de l'acide carboxylique sur la surface de la micelle. Parametres cinetiques

The process of the micelle dissociation of sodium dodecyl sulfate (SDS) was observed by a stopped-flow method applying the specific absorption band. The absorbance change observed in the dilution from above the CMC to below the CMC was attributed to the next reaction DS n →k +mS, (n>m) where DSn is the micelle solubilizing the dye, D′ is the salt of the dye cation with the detergent anion, S is the detergent monomer, and k is the overall micelle dissociation rate constant. The micelle dissociation rate constant was calculated to be 5.5 sec−1 at 42°C.

The effect of torsional prestrain on tensile and low-cycle fatigue properties of a medium carbon steel was studied. A series of small-sized tensile and fatigue specimens were prepared from large-sized prestrained specimens in order to ensure good homogeneity of the torsional prestrain in the cross-section of the small-sized specimens. Three modes of prestraining were selected in this study; unidirectional, twistback, and single- or cyclic-reversed torsion. Fracture ductility decreased almost linearly with increasing unidirectional prestrain, while the decrease of fracture ductility in the other modes of prestrain was much less than that in the unidirectional one. A transitional decrease in fracture ductility, which has been reported for inhomogeneously prestrained specimens, was not observed in this study. A slight trace of recovery in fracture ductility due to twisting back the unidirectional prestrain to the macroscopically undistorted original state was observed, in contrast with the almost complete recovery for the inhomogeneously prestrained specimens. The low-cycle life of the unidirectionally prestrained specimens was reduced by an amount which would be predictable from the decrease in fracture ductility of those specimens. For other modes of prestrain, however, the influence on fatigue life was undistinguishably small in this study.

代表的な緩和法としての超音波法および温度ジャンプ法を併用して,10-9～10-2秒の広い時間範囲にわたり液体および溶液中の動的平衡に関する速度論的研究を行なった。液体中の平衡については液体カルボン酸の例としてプロピオン酸の超音波吸収の濃度および温度変化の測定を行ない,吸収は分子間水素結合によるカルボキシル基間のキレート環の水素結合の一つが切れる反応によることを明らかにし,反応に関する諸量をえた。また強い分子内水素結合を形成するサリチル酸メチル,サリチルアルデヒドについても超音波吸収を見いだし,類似化合物についての結果などから吸収が分子内水素結合によることを明らかにするとともに,分子内水素結合形成反応に関する速度論的諸量を求めた。溶液内動的平衡としてはまず超音波法によってプロトン移行に基づく加水分解反応をリン酸三ナトリウム,メタホウ酸ナトリウムなどの無機電解質および生体高分子の各種構成アミノ酸について吸収または分散を測定しその機構を明らかにした。また多価カルボン酸についてはPH変化から酸解離反応によることを究明した。一方,高分子については温度ジャンプ法により色素の単量体＝ニ量体反応,分子の集合体としてのミセルと色素間の平衡,超音波法により界面活性剤ミセルと対イオン間の動的平衡,高分子のヘリックス＝ コイル相転移反応に関して研究し,その機構を明らかにするとともに反応に関する諸量をえた。金属錯体形成反応については超音波法を用いてきわめてはやい2価金属イオンの1価の配位子による配位水交換反応.温度ジャンプ法によって比較的ゆっくりした鉄イオンと配位子との錯体形成反応についても速度論的研究を行なった。

In order to gather information relating to the low-cycle fatigue behavior of anisotropic materials, the low-cycle fatigue prorerties of thick rolled steel plates were investigated in several directions under the condition of uniaxial tension-compression. The steel plates used showed considerable anisotropy in fracture ductility in the thickness direction, while anisotropy in the yield and ultimate tensile strengths was observed to be very slight in any direction. The low-cycle fatigue behavior was also the most anisotropic in the thickness direction. The fracture life in a given direction, however, was found to follow the Manson-Coffin type relation, which is usually applied to isotropic materials, if the fracture ductility determined from the tensile test in that direction was used. The crack initiation life also exhibited a similar trend, although in a more exaggerated manner. Differences were found in fracture mode depending on the directions relative to the rolling direction.

The temperature-jump method was used to study the kinetics of FeCl2+ and FeBr2+ complex formations in aqueous solutions. Complex formation is composed of two paths. In the acid-independent path, the rate-determining step of complex formation may be the reaction between Fe(H2O)53+ and X− (X−=Cl−, Br−). The other path is that via the hydrolysis of ferric ions, and the rate-determining step is the loss of a water molecule from the inner coordination sphere of the metal ion. The kinetic values obtained are in good agreement with the results obtained by the flow method.

Individual variation of serum α1-antitrypsin, a protease inhibiting protein, was studied by starch gel electrophoresis. A total of 1, 475 serum and plasma samples taken from three racial groups, namely Japanese, Ainu and U. S. A. White, were examined. Seven phenotypes altogether found were classified according to FAGERHOL's nomenclature of Pi-system. In each population group the type MM was by far the most common, while other variants had low incidence. A similar frequency distribution was found in the Japanese population to that in U. S. A. White, except that type MF was commoner and type MS rarer in the former than in the latter. A reduced heterogeneity in the Ainu population was indicated. Gene frequencies were estimated on the basis of the postulated genetic mode of codominant alleles at a locus. It is found that the α1-antitrypsin deficient type occurs also in Japan, although there is still uncertainty as to whether this is genetically a homogeneous phenotype. No difference in the trypsin inhibiting capacity was found among the three racial groups.

Individual variations ofα 1-antitrypsin of the macaques were investigated by means of starch gel electrophoresis. The material comprised a total of 1,084 plasma samples taken from six species, namely,Macaca irus, mulatta, cyclopis, nemestrina, speciosa, andfuscata, including several geographical groups. At least ten phenotypes which were assumed in analogy to human Pi-system to be under genetic control of five codominant alleles tentatively denoted byPi were identified. It was considered that these alleles are commonly possessed by different macaque species. A marked difference in the distribution of allele frequencies was found both within and between species groups. Several aspects of this new polymorphic variation in the macaques were discussed with special reference to the geographical distribution of the alleles and the origins of the Japanese macaque,M. fuscata.

The biaxial low-cycle fatigue properties of anisotropic rolled steel plates were investigated. Biaxial low-cycle fatigue tests were conducted by utilizing the principle of anticlastic bending of flat rhombic plates. Crack initiation and propagation were examined with special reference to angles between the applied principal stress axes and the anisotropy axes of the material studied. The biaxial fatigue life of anisotropic specimens cut out in a given direction satisfied a linear relation on a log-log scale between an equivalent strain range and the number of cycles to failure. The direction of crack initiation under the uniaxial and biaxial stress conditions was coincident with that of the maximum shear stress. The fatigue life under the uniaxial stress condition was shorter than that determined under the biaxial stress condition for a given value of the equivalent strain range. The discrepancies were interpreted in terms of both normal stress component acting on the crack surface and the modes of crack propagation.

Ultrafine magnetite particle (Fe3O4) which adsorbed the 7,7,8,8-tetracyanoquinodimethane (TCNQ)dioctadecyldimethylammonium bromide (DODAB) bilayer on the surface were prepared in an aqueous solution by sonication. A single relaxation was found by using the electric-field-pulse method and was attributed to the association-dissociation process of the electron-donor-acceptor complexes involving TCNQ solubilized at the DODAB bilayer/magnetite particle interface.

The dimerization reaction of dye, Rhodamine 6G, in aqueous solution was studied spectrophotometrically and kinetically: the equilibrium constant and the rate constants were found to be K=1.6×103 M−1, kf=1.1×109 M−1 s−1, and kb=7.0×105 s−1, respectively, at 15 °C. These rate constants, and those of other dyes are discussed. The effect of the ionic strength was also studied.

Kinetic studies of the dimerization reaction of thionine in an aqueous solution have been performed by the laser temperature-jump method with the use of the stimulated Raman effect in high-pressure H2 gas. From the concentration dependence of the relaxation time, the formation and dissociation rate constants of the thionine dimer have been obtained. The data have been confirmed by the equilibrium constant, independently obtained spectrophotometrically. The formation rate constant of the dimer was very large, and the process was revealed to be a diffusion-controlled reaction, similar to those with other dyes.