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In the title compound, cis-[Pd(C5H14NP)2]Cl2·CH4O, the coordination geometry around the PdII center is distorted square planar, with a cis-P2N2 configuration of the two chelating (3-aminopropyl)dimethylphosphine (pdmp) ligands. The six-membered pdmp chelate rings adopt chair conformations, and pairing of the chairs designates the complex cation as a (Cs)-chair2 conformer. The distances between the PdII center and the Cl- anions are greater than 4.5 Å, indicating no obvious interaction. [ABSTRACT FROM AUTHOR]

Purple prismatic crystals of the title compound, [Co2(C3H6NS2)4(C8H11O2P)2](PF6)2, were obtained by repeated recrystallization of trans-[Co(C3H6NS2)2-(C8H11O2P)2]PF6 from CH3CN/Et2O and then from MeOH/CH2Cl2; during recrystallization one of the P(OMe)2Ph ligands was dissociated from the CoIII center and the resulting CoIII complex fragment underwent dimerization. The complex cation has a dinuclear structure bridged by one S atom of each of two of the N, N-di­methyl­di­thio­carbamate ligands, and has crystallographically imposed C2 symmetry. Two P(OMe)2Ph ligands are coordinated at the transoid positions of the Co2(μ-C3H6NS2)2(C3H6NS2)2 moiety, with Co-P bond lengths of 2.1921 (11) Å. [ABSTRACT FROM AUTHOR]

Phthalocyanine that has four peripheral 2-methoxyphenyl substituents at the α-position and its Zn(II) and Cu(II) complexes were synthesized. Chemical oxidation by the Cu(II) ion and electrochemical oxidation of these metal complexes were investigated spectrophotometrically in acetonitrile. The UV-visible absorption spectra of these metal complexes and their one-electron oxidized π-cation radicals showed no concentration dependence, indicating that these species exist as monomers in solution. Kinetics of the thermal electron transfer reaction from each phthalocyanine complex to Cu2+ and the photoinduced electron transfer reaction of the Zn(II) phthalocyanine complex with V(V) and V(IV) Schiff base complexes were studied using conventional spectrophotometric and transient absorption techniques, and the electron transfer rate constants were analysed using the Marcus cross relationship. The obtained rate constants of the electron self-exchange reaction between the parent phthalocyanine complexes and their π-cation radicals were in the order of 109 to 1011 M−1 s−1 at T = 298.2 K. These large electron self-exchange rate constants are consistent with the phthalocyanine-centred redox reactions where small reorganization energies are required with little structural change during the electron transfer process. [ABSTRACT FROM AUTHOR]

The kinetics of oxidation of tellurium(iv) by [IrCl6]2− in aqueous perchlorate solutions at a constant ionic strength of 0.1 mol dm−3 have been investigated spectrophotometrically. The results showed a first-order dependence in [IrCl6]2−, fractional-first-order kinetics with respect to tellurium(iv) concentration and second-order overall kinetics. The increase in the [H+] was found to be accompanied by a decrease in the rate constants, i.e., the oxidation reaction was acid-inhibited. Kinetic evidence for the formation of a 1 : 1 intermediate binuclear complex between the two reactants has been obtained. The ionization constant of tellurium(iv) has been evaluated and found to be 1.69 × 10−3 dm3 mol−1 at 25 °C. The kinetic parameters have been calculated and a tentative reaction mechanism consistent with the kinetic data is suggested. [ABSTRACT FROM AUTHOR]

Abstract: Zircon fission-track (FT) and U–Pb analyses were performed on zircon extracted from a pseudotachylyte zone and surrounding rocks of the Asuke Shear Zone (ASZ), Aichi Prefecture, Japan. The U–Pb ages of all four samples are ∼ 67–76 Ma, which is interpreted as the formation age of Ryoke granitic rocks along the ASZ. The mean zircon FT age of host rock is 73±7 (2σ) Ma, suggesting a time of initial cooling through the zircon closure temperature. The pseudotachylyte zone however, yielded a zircon FT age of 53±9 (2σ) Ma, statistically different from the age of the host rock. Zircon FTs showed reduced mean lengths and intermediate ages for samples adjacent to the pseudotachylyte zone. Coupled with the new zircon U–Pb ages and previous heat conduction modeling, the present FT data are best interpreted as reflecting paleothermal effects of the frictional heating of the fault. The age for the pseudotachylyte coincides with the change in direction of rotation of the Pacific plate from NW to N which can be considered to initialize the NNE–SSW trending sinistral–extensional ASZ before the Miocene clockwise rotation of SW Japan. The present study demonstrates that a history of fault motions in seismically active regions can be reconstructed by dating pseudotachylytes using zircon FT thermochronology. [Copyright &y& Elsevier]

Kinetic measurements of the reactions of (N‐methyl)‐4‐pyridinium boronic acid [(N−Me)‐4‐Py+B(OH)2] and 4‐pyridinium boronic acid [4‐HPy+B(OH)2] with D‐sorbitol in aqueous solution were performed, and the reaction mechanisms were clarified in detail. Both reactions proceeded in one step; i. e., the intermolecular rate‐determining step forming the 2,3‐bicoordinate product was followed by the fast intramolecular step from the bicoordinate product to the 2,3,5‐tricoordinate product. N‐Methylation of 4‐HPy+B(OH)2 was found to dramatically reduce the reactivity of the N‐methylated‐4‐pyridinium boronate ion [(N−Me)‐4‐Py+B(OH)3−], although it had little effect on the reactivity of (N−Me)‐4‐Py+B(OH)2. The reaction rates were enhanced by ion‐pair formation between the boronate ion and the protonated buffer cation. [ABSTRACT FROM AUTHOR]

The second-order electron transfer reaction between the photo-excited triplet state of [Zn(TPP)]* (TPP = 5,10,15,20-tetraphenylporphyrin) and [Co(sep)]3+ (sep = sepulchrate = 1,3,6,8,10,13,16,19-octaazabicyclo[6.6.6]eicosane) was investigated in three ionic liquids (ILs, 1-R-3-methylimidazolium bis(trifluoromethylsulfonyl)imide with R = butyl, pentyl, and hexyl) and in acetonitrile. Results of electrochemical and kinetic measurements indicated that ILs dissociate in the vicinity of charged metal complexes and at electrodes, although the dissociated anionic and cationic components of the ILs seem to exist as pairs around the metal complexes. Second-order rate constants for the electron transfer reaction are 1.88 × 109, 3.65 × 107, 2.63 × 107, and 2.01 × 107 kg·mol−1·s−1 in acetonitrile and in the butyl, pentyl and hexyl ILs, respectively, at 298 K, after correction of the contribution of diffusion. The average slope of the plot of the logarithmic second-order rate constants observed in acetonitrile and ILs against the logarithmic viscosity of each solvent was − 0.84. However, the slope of the same plot was much steeper (− 4.1) when data for only the three ILs were used. Detailed analyses of the experimental results on the basis of the Latner-Levin cross relation and the Marcus theory lead to the conclusion that the solvent properties such as the dielectric constant and refractive index around the polarized/charged transition states are different from those for the bulk ILs: observed self-exchange rate constants did not exhibit the Pekar factor dependence when dielectric constants and refractive indices for bulk ILs are used. [ABSTRACT FROM AUTHOR]

New dyad systems based on a zinc(ii) porphyrin complex and a 2,2′-bipyridine moiety linked by amide bridges having various bridging groups were synthesized. The photochemical behavior was investigated using fluorescence spectroscopy and a time-resolved absorption technique. The singlet excited state of the porphyrin complex was found to be partially quenched by Cu2+ in methanol, and a photoinduced electron transfer from the excited state of the porphyrin moiety to the Cu(ii)-bipyridine moiety was observed using a transient absorption technique. The relatively long lifetime of the charge-separated state was ascribed to the slow electron-transfer reaction of the Cu(ii)/Cu(i) couple bound to the bipyridine moiety. The lifetime of the charge-separated state of dyads becomes longer with the increase of the distance between the porphyrin and bipyridine moieties, and these findings are discussed using an empirical formula for the relationship between the reactivity and molecular structure of dyads. [ABSTRACT FROM AUTHOR]

The reaction of d -fructose with diphenylborinic acid (Ph 2 B(OH)), to which d -fructose cannot coordinate tridentately, was kinetically investigated in order to solve the reaction mechanism, and to find a clue to resolve the two-step reaction mechanism of boronic acid (RB(OH) 2 ) with d -fructose. The title reaction was a single-step reaction under the pseudo first-order conditions with large excess d -fructose over Ph 2 B(OH), which suggests that the reaction of RB(OH) 2 with d -fructose consists of the fast formation of a two-coordinate complex followed by the slow formation of a three-coordinate complex. The kinetic reactivity of Ph 2 B(OH) was considerably higher than that of its conjugate base, diphenylborinate ion (Ph 2 B(OH) 2 − ). It was shown that Ph 2 B(OH) 2 − interacted with CHES buffer to form an outer-sphere complex, whereas no interaction was observed between Ph 2 B(OH) and CHES buffer. Both the free borinate ion and the restrained borinate ion into the outer-sphere complex react with d -fructose to form the chelate complex via stable binary and ternary outer-sphere complexes, respectively. [ABSTRACT FROM AUTHOR]

Six-coordinate [Cu(pdt)2(H2O)2]2+ and four-coordinate [Cu(pdt)2]+ complexes were synthesized and the cross redox reactions were studied in acetonitrile (pdt = 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine). Single crystal analyses revealed that [Cu(pdt)2(H2O)2](BF4)2 was of pseudo-D2h symmetry with two axial water molecules and two symmetrically coordinated equatorial pdt ligands, while the coordination structure of [Cu(pdt)2]BF4 was a squashed tetrahedron (dihedral angle = 54.87°) with an asymmetric coordination by two pdt ligands: one pdt ligand was coordinated to Cu(i) through pyridine-N and triazine-N2 while another pdt ligand was coordinated through pyridine-N and triazine-N4, and a stacking interaction between the phenyl ring on one pdt ligand and the triazine ring on another pdt ligand caused the squashed structure and non-equivalent Cu–N bond lengths. The cyclic voltammograms for [Cu(pdt)2(H2O)2]2+ and [Cu(pdt)2]+ in acetonitrile were identical to each other and quasi-reversible. The reduction of [Cu(pdt)2(H2O)2]2+ by decamethylferrocene and the oxidation of [Cu(pdt)2]+ by [Co(2,2′-bipyridine)3]3+ in acetonitrile revealed that both cross reactions were sluggish through a gated process (the structural change took place prior to the electron transfer) accompanied by slow direct electron transfer processes. It was found that the triazine ring of the coordinated pdt ligand rotates around the C–C bond between the triazine and pyridine rings with the kinetic parameters k = 51 ± 5 s−1 (297.8 K), ΔH‡ = 6.2 ± 1.1 kJ mol−1 and ΔS‡ = −192 ± 4 J mol−1 K−1. The electron self-exchange process was directly measured using the line-broadening method: kex = (9.9 ± 0.5) × 104 kg mol−1 s−1 (297.8 K) with ΔH‡ = 44 ± 7 kJ mol−1 and ΔS‡ = 0.2 ± 2.6 J mol−1 K−1. By comparing this rate constant with the self-exchange rate constants estimated from the cross reactions using the Marcus cross relation, the non-adiabaticity (electronic) factors, κel, for the direct electron transfer processes between [Cu(pdt)2]+/2+ and non-copper metal (Fe2+ and Co3+) complexes were estimated as ca. 10−7, indicating that the electronic coupling between the d orbitals of copper and of non-copper metals is very small. [ABSTRACT FROM AUTHOR]

To establish a detailed reaction mechanism for the condensation between a boronic acid, RB(OH)2, and a diol, H2L, in aqueous solution, the acid dissociation constants ( ${K{{{\rm BL}\hfill \atop {\rm a}\hfill}}}$) of boronic acid diol esters (HBLs) were determined based on the well-established concept of conditional formation constants of metal complexes. The p Ka values of HBLs were 2.30, 2.77, and 2.00 for the reaction systems, 2,4-difluorophenylboronic acid and chromotropic acid, 3-nitrophenylboronic acid and alizarin red S, and phenylboronic acid and alizarin red S, respectively. A general and precise reaction mechanism of RB(OH)2 with H2L in aqueous solution, which can serve as a universal reaction mechanism for RB(OH)2 and H2L, was proposed on the basis of (a) the relative kinetic reactivities of the RB(OH)2 and its conjugate base, that is, the boronate ion, toward H2L, and (b) the determined p Ka values of HBLs. The use of the conditional formation constant, K′, based on the main reaction: RB(OH)2+H2L ${{\mathop \leftrightarrow \limits ^{K{_{1}}}_{}}}$ RB(L)(OH)−+H3O+ instead of the binding constant has been proposed for the general reaction of uncomplexed boronic acid species (B′) with uncomplexed diol species (L′) to form boronic acid diol complex species (esters, BL′) in aqueous solution at pH 5-11: B′+L′ ${{\mathop \leftrightarrow \limits ^{K{^\prime}}_{}}}$ BL′. The proposed reaction mechanism explains perfectly the formation of boronic acid diol ester in aqueous solution. [ABSTRACT FROM AUTHOR]

The reduction reaction of the Cu(II)-pitn complex (pitn = 1,3-di(pyridine-2-carboxaldimino)propane) by decamethylferrocene [Fe(Cp*)] was examined in acetonitrile. The observed pseudo-first-order rate constants exhibited saturation kinetics with increasing excess amount of [Fe(Cp*)]. Detailed analyses revealed that the reaction is controlled by a structural change prior to the electron transfer step, rather than a conventional bimolecular electron transfer process preceded by ion pair (encounter complex) formation. The rate constant for the structural change was estimated to be 275 ± 13 s at 298 K (∆ H* = 33.3 ± 1.0 kJ·mol, ∆ S* = 86 ± 5 J·mol·K), which is the fastest among gated reactions involving CuN complexes. It was confirmed by EPR measurement and Conflex calculations that the dihedral angle between the two N-N planes is significantly large (40°) in solution whereas it is merely 17.14° in the crystal. [ABSTRACT FROM AUTHOR]

New iron(II) complexes were synthesized with two tridentate hybrid ligands having phosphorous and nitrogen donor sites, in order to quantitatively estimate the difference of the ligand-field strengths of phosphorous and nitrogen donor sites in cationic metal complexes. Iron(II) complexes with bis(dimethylphosphinoethyl)amine (PNP) and 2,6-bis(diphenylphosphinomethyl)pyridine (PpyP) ligands crystallized as un- symmetric facial-[Fe(PNP)](PF)·CHNO and mer-[Fe(PpyP)](CFSO), respectively, as expected from the steric congestion and from the tendency to avoid the mutual trans influence between two phosphorous donor sites. Both complexes are in the low-spin electronic state up to 400 K. The pseudo- D coordination geometry of the PpyP complex made it possible to separate axial (2 × N) and equatorial (4 × P) contributions to the overall ligand-field by means of a spectrometric method: the difference in the ligand-field strengths by the equatorial PhP-donor sites and by the axial 2,6-disubstituted pyridine donor sites is ca. 13,200 cm. A significantly reduced inter-electronic repulsion parameter (425 cm for both PNP and PpyP complexes) from the value of the free ion (1,060 cm) indicates covalent interaction between the Fe(II) and P atoms even in these cationic metal complexes. It is shown that the degree of covalency as well as the coordination bond strengths between various metal ions and phosphorous/nitrogen donor atoms is successfully explained by the relative energy levels of interacting atomic orbitals calculated on the basis of the Thomas-Fermi-Dirac potential. [ABSTRACT FROM AUTHOR]

A series of phosphine-substituted ruthenium polypyridine complexes, cis(P,Cl)-[Ru(trpy)(Pqn)Cl]PF6 (cis-Cl), trans(P,MeCN)-[Ru(trpy)(Pqn)(MeCN)](PF6)2 (trans-PN), cis(P,MeCN)-[Ru(trpy)(Pqn)(MeCN)](PF6)2 (cis-PN), and [Ru(trpy)(dppbz)(MeCN)](PF6)2 (PP), were synthesized and crystallographically characterized (trpy = 2,2':6',2?-terpyridine, Pqn = 8-(diphenylphosphanyl)quinoline, and dppbz = 1,2-bis(diphenylphosphanyl)benzene). In electrochemical measurements for cis-PN and PP, the reduction of cis-PN resulted in the formation of trans-PN via cis-trans isomerization and that of PP proceeded via a two-electron-transfer reaction. The mechanism of the electrochemical behaviors is discussed through consideration of five-coordinated species, [Ru(trpy)(Pqn)]n+ or [Ru(trpy)(dppbz)]n+ (n = 0-2), formed by liberation of a monodentate labile ligand. [ABSTRACT FROM AUTHOR]

The following reaction systems, with and without proton ambiguity, were set up for direct measurements of the rate constants of borate and boronate ions: boric acid [B(OH)3] and 4,5-dihydroxy-1,3-benzenedisulfonic acid disodium salt (Tiron); 3-nitrophenylboronic acid [3-NO2PhB(OH)2] and Tiron; phenylboronic acid [PhB(OH)2] and 4-nitrocatechol; boric acid and 4-nitrocatechol. Each rate constant for boric or boronic acid is larger than that for the conjugate borate or boronate ion for the reaction systems without proton ambiguity. These results explicitly indicate that the widespread belief that the rate constants of boronate ions are several orders of magnitude larger than those of the conjugate boronic acids is erroneous. The relative kinetic reactivities of RB(OH)2 and RB(OH)3- were investigated in relation to the linear free energy relationships between the rate constants and acidities of the boronic acids and diols. [ABSTRACT FROM AUTHOR]

Abstract: A zinc(II) porphyrin complex bearing a bipyridine moiety at the periphery was synthesized. The singlet excited state of the complex was found to be quenched by Cu2+ in methanol, and the photoinduced electron transfer from the excited state of the porphyrin to the bipyridine moiety in the presence of excess Cu2+ ion was observed using a transient absorption technique. The relatively long lifetime of the charge-separated state was ascribed to the slow electron exchange reaction of Cu(II)/Cu(I) couple bound to the bipyridine unit. [Copyright &y& Elsevier]

Abstract: The kinetics of chromic acid oxidation of chondroitin-4-sulfate polysaccharide as sulfated carbohydrates at a constant ionic strength of 4.0moldm−3 has been investigated, spectrophotometrically. The reaction kinetics showed a first-order dependence in chromic acid and fractional-first-order kinetics with respect to the chondroitin-4-sulfate concentration. The influence of [H+] on the reaction rates showed that the oxidation process is acid-catalyzed. Added Mn2+ ions indicated the formation of Cr(IV) as intermediate species. A kinetic evidence for formation of 1:1 intermediate complex was revealed. The kinetic parameters have been evaluated and a tentative reaction mechanism in good consistent with the kinetic results obtained is discussed. [Copyright &y& Elsevier]

Abstract: To constrain the thermal and its spatial conditions of pseudotachylyte formation and cooling, we dated zircons from a pseudotachylyte in the Ryoke belt obtained about 100m north from the Median Tectonic Line in the Taki area, southwest Japan, and its host rock, the Hatai Tonalite, by the (U–Th)/He method. The ages obtained are 60.3±2.7 and 55.5±4.5 (1SE) Ma, respectively, which are essentially the same within the error. This is the first (U–Th)/He age directly measured for a pseudotachylyte. The coincidence between these ages indicates that the pseudotachylyte formed at ca. 60Ma under the ambient temperature of about 180°C, the closure temperature of zircon (U–Th)/He method. The Fish Canyon Tuff zircon, one of the most well-known geological age standards, was also dated to confirm the validity of our analyses, which yielded the weighted mean age of 29.6±1.5 (1SE) Ma, consistent with other reported ages. The average cooling rates and denudation rates of the host rock were calculated based on these ages, reported zircon fission-track ages (ca. 70Ma) and apatite fission-track ages (ca. 40Ma) as about 12°C/Myr and about 0.6mm/yr from 70 to 60Ma, and about 4°C/Myr and about 0.2mm/yr from 60 to 40Ma, respectively, assuming that the closure temperatures of zircon and apatite FT methods are 300°C and 110°C, respectively, and a geothermal gradient of 20°C/km. One possible reason of this slow down of denudation rates is the decrease of convergent rate and change in the movement direction of the Pacific Plate relative to the Eurasian Plate along the southwest Japan in the Paleogene. [Copyright &y& Elsevier]

Abstract: The kinetics of oxidation of iota- and lambda-carrageenan as sulfated carbohydrates by permanganate ion in aqueous perchlorate solutions at a constant ionic strength of 2.0moldm−3 have been investigated spectrophotometrically. The pseudo-first-order plots were found to be of inverted S-shape throughout the entire courses of reactions. The initial rates were found to be relatively slow in the early stages, followed by an increase in the oxidation rates over longer time periods. The experimental observations showed first-order dependences in permanganate and fractional first-order kinetics with respect to both carrageenans concentration for both the induction and autoacceleration periods. The results obtained at various hydrogen ion concentrations showed that the oxidation processes in these redox systems are acid-catalyzed throughout the two stages of oxidation reactions. The added salts lead to the prediction that MnIII is the reactive species throughout the autoacceleration periods. Kinetic evidence for the formation of 1:1 intermediate complexes was revealed. The kinetic parameters have been evaluated and tentative reaction mechanisms in good agreement with the kinetic results are discussed. [Copyright &y& Elsevier]

The tetrafluoroborate salt of bis{8-(diphenylphosphino)quinoline}copper(I), [Cu(Ph2Pqn)2]BF4, afforded orange prismatic (2O) or yellow columnar (2Y) crystals, dependent on the solvent and concentration of the recrystallization solution used. X-ray analysis revealed that crystals of 2O and 2Y had the same composition and exhibited different crystal systems: 2O was triclinic, with space group P1 and Z = 2, and 2Y was monoclinic with space group P21/c and Z = 4. In these crystals, the tetrahedral copper(I) complex exhibited a strong "rocking distortion" toward a trigonal pyramidal coordination geometry (by a slide translation of one of the unsymmetrical bidentate chelating ligands along the tetrahedral edge). In addition, both the 2O and 2Y complexes showed a "flattening distortion", meaning that the dihedral angle between the two chelate planes were off-perpendicular and oriented toward opposite directions, which resulted in a pair of distortion isomers: syn clinal (sc: 2O) and anti clinal (ac: 2Y). 31P CP-MAS NMR spectroscopy indicated that 2O and 2Y could be distinguished. Both isomers exhibited inequivalent P atoms, but a larger difference in chemical shift was observed in 2Y. TD-DFT calculations reproduced the difference in spectra between the orange- and yellow-colored complexes, which originated from metal-to-ligand charge-transfer transitions. [ABSTRACT FROM AUTHOR]

The article presents the results of the outcrop structural analysis of dextral movement of Tanakura Shear Zone in Japan. It says that the shear senses and composite shear planes were determined from the outcrop and oriented gouge samples. Results indicated a dextral sense of shear with a dip-slip component on the basis of clast deformation. It adds that no structural evidence was found for the superposition of deformation due to the severe postdates brittle dextral shearing in the outcrop area.

Abstract: Kinetic studies were performed on the reactions of phenylboronic acid with L-lactic acid and mandelic acid in acidic aqueous and alkaline solutions in order to specify reactive species in these reactions. It was confirmed that the diprotonated ligand (H2L: L-lactic acid or mandelic acid) is less reactive than the monoprotonated ligand (HL−: L-lactate ion or mandelate ion), which made possible direct determination of the rate constants of phenylboronic acid (PhB(OH)2) and its conjugate base, phenylboronate ion (PhB(OH)3 −). It was found that PhB(OH)2 is more reactive than PhB(OH)3 −. On the basis of kinetic results, it was concluded that the most reactive species are PhB(OH)2 and HL− at physiological pH 7.4, so the reaction in the boronic acid-based sensor for L-lactate mainly would occur between these species. [ABSTRACT FROM AUTHOR]

Abstract: Spectrophotometric evidence for the formation of hypomanganate(V), [CAR-], and manganate(VI), [CAR-], intermediate complexes has been confirmed during the oxidation of iota- and lambda-carrageenan-sulfated polysaccharides (CAR) by alkaline permanganate at pHs ⩾12 using a conventional spectrophotometer. These short-lived intermediate complexes were identified and characterized. A reaction mechanism in good consistence with the experimental results is suggested. [Copyright &y& Elsevier]

Abstract: The acid-catalysis of chromic acid oxidation of carboxymethyl cellulose (CMC) as a polysaccharide in aqueous perchlorate solutions at a constant ionic strength of 2.0moldm−3 have been investigated spectrophotometrically. The experimental results showed first-order kinetics in chromic acid and fractional first-order dependence with respect to [CMC]. A kinetic evidence for the formation of 1:1 complex between chromic acid and CMC was revealed. The hydrogen ion dependence of the reaction rates showed that the oxidation process is acid-catalyzed. Induced polymerization of acrylonitrile indicated that the oxidation process proceeds by free-radical mechanism. The kinetic parameters have been evaluated and a tentative reaction mechanism consistent with the kinetic results is suggested. [Copyright &y& Elsevier]

Abstract: An anisotropy of magnetic susceptibility (AMS) analysis was conducted for a typical S–C mylonite in a small-scale ductile shear zone derived from Late Cretaceous magnetite- free granite in the Ryoke Belt, Teshima Island, southwest Japan. In such mylonites, paramagnetic minerals such as biotite and hornblende, which define foliations, are assumed to control the AMS. Accordingly, we attempted to measure the orientations of both minerals to correlate the S–C–C′ fabric to the AMS using techniques of microscopic and back-scattered electron (BSE) image analyses. A measured magnetic fabric of the S–C mylonite that is expressed by a K min normal plane (K max–K int plane) approximated S foliation, K max orientation coincided well with the orientations of mean resultant vectors for long axes of biotite and minor hornblende, whereas K max did not coincide well with those of the mean resultant vectors for long axes of the brighter domain (aggregates of biotite and minor hornblende) from the binary BSE image. These results show that the magnetic fabric fairly reflects the shape preferred orientation of individual grains of paramagnetic monoclinic minerals, especially biotite, which forms the S–C–C′ fabric. [Copyright &y& Elsevier]