Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 60 , Issue 8
Showing 1-50 articles out of 74 articles from the selected issue
  • Ryuki Hashitani, Shinobu Koda, Hiroyasu Nomura
    1987 Volume 60 Issue 8 Pages 2705-2711
    Published: 1987
    Released: June 27, 2006
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    The sound velocities of mixtures of tri-o-tolyl phosphate and diisobutyl phthalate were measured by means of the Brillouin scattering method in the temperature range from 214 to 333 K. The velocity dispersion was observed in the mixtures at temperatures from 273 to 323 K in the gigahertz region. The velocity dispersion was attributed to the structural relaxation, as in the case of pure highly viscous liquids. The reduced variable method proposed by Lamb et al. could not be applied to the storage moduli over wide frequency and temperature ranges. The relaxation curves of the reduced storage modulus obtained at room temperature, where the viscosity obeyed the Arrhenius equation, were well expressed by a single relaxation equation. The structural relaxation mechanism of the highly viscous liquids investigated here is related to the weak cooperative motions of molecules in the liquid state. The activation energy, ΔEr, obtained from the temperature dependences of the relaxation times was about a third of those estimated from the Arrhenius plots of the shear viscosities of the mixtures.
  • Kosaku Suga, Shigeru Aoyagui
    1987 Volume 60 Issue 8 Pages 2713-2718
    Published: 1987
    Released: June 27, 2006
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    Nitrobenzene anion radical was stably prepared by the electrolytic reduction of nitrobenzene solution containing various kinds and amounts of tetraalkylammonium perchlorates. The rate constants of homogeneous electron-transfer reactions of these nitrobenzene anion radicals with nitrobenzene molecules as a solvent were determined by ESR method at various temperatures. These rate constants at 25 °C were about 107 dm3 mol−1 s−1 and comparable with the rate constant of electron-transfer reation between nitrobenzene and its anion radial in N,N-dimethylformamide. The quasi-first order rate constants evaluated from these rate constants were about 108 s−1 and were larger than the rate constants of the intramolecular electron-transfer reactions of the anion radical of bis(p-nitrophenyl) compounds except for bis(p-nitrophenyl)methane. The absorption spectrum of the solution of nitrobenzene anion radical in nitrobenzene containing 0.1 M tetrabutylammonium perchlorate or 0.1 M tetraethylammonium perchlorate showed an additional weak peak at about 800 or 900 nm as well as the ordinary peak. The light energies of these additional peaks were in good agreement with the energy values of the optical electron-transfer reactions evaluated according to the theory of Hush from the activation energies of corresponding thermal electron-transfer reactions. The rate constants of electrochemical electron-transfer reactions and the diffusion coefficients of nitrobenzene anion radical in nitrobenzene were also measured.
  • Makoto Okawauchi, Mayumi Hagio, Yoshitomi Ikawa, Gohsuke Sugihara, Yos ...
    1987 Volume 60 Issue 8 Pages 2719-2725
    Published: 1987
    Released: June 27, 2006
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    The physicochemical properties of N-alkanoyl-N-methylglucamine in aqueous solution have been studied by applying a Debye plot and small-system thermodynamics to an analysis of static light scattering data in the temperature range from 25 to 55 °C. A small minimum was found in a plot of the critical micelle concentration vs. temperature, instead of the monotonously decreasing tendency, as in the case of poly(oxyethylene) alkyl ether. The temperature dependence of the aggregation number of the micelle and the spread of the aggregation number distribution of micelle are both very small. The standard enthalpy change associated with micelle formation varies from positive to negative as the temperature is raised. The micellization of N-alkanoyl-N-methylglucamine surfactants is discussed separately in terms of the respective contributions from the hydrophilic and hydrophobic groups.
  • Kenzo Hiraoka, Hajime Takimoto, Shinichi Yamabe
    1987 Volume 60 Issue 8 Pages 2727-2735
    Published: 1987
    Released: June 27, 2006
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    The ion/molecule reactions observed in 4 Torr CH4 containing known small amounts of i-C3H7OH or i-C3H7OH/H2O mixture were studied over the temperature range 40–400 °C. The experiments were carried out using a pulsed electron beam mass spectrometer. At low temperatures (<150 °C), the major ions are i-C3H7OH2+(i-C3H7OH)n. By increasing the temperature, the slow growth of ions with mz=59, 85, and 101 is observed. These ions are assigned to (CH3)2COH+, (CH3)2CHC+(CH3)2, and C6H13O+, respectively. They are probably produced from reactions of i-C3H7+ with isopropyl alcohol. The (CH3)2COH+ ion may be produced from the electrophilic attack of i-C3H7+ onto the secondary carbon atom of i-C3H7OH. At high temperatures (≈400 °C), the (CH3)2COH+ ion becomes dominant. Acid-catalyzed dehydration of isopropyl alcohol, i-C3H7OH2++H2O→H3O+(H2O)+C3H6, is also observed. Ion/molecule reactions involved in the present experiment are discussed according to the frontier-orbital theory.
  • Mutsuyoshi Matsumoto, Takayoshi Nakamura, Motoo Tanaka, Tatsuo Sekiguc ...
    1987 Volume 60 Issue 8 Pages 2737-2742
    Published: 1987
    Released: June 27, 2006
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    The structures of the Langmuir–Blodgett (LB) films of the ordinary mixed monolayer (LPF) and the supermonomolecular layer (HPF) of a surface active squarylium dye-icosanoic acid binary mixed system were examined by absorption spectroscopy. The absorption spectra of one unit layer of LPF with a molar mixing ratio ranging from 1/10 to 1/1 were almost the same, strongly suggesting that each component exists separately in the films. The LB films of two unit layers of LPF showed two peaks at 590 and 560 nm ascribed to intralayer and interlayer aggregates, respectively, besides the monomeric peak at 640 nm. The absorption spectra of one unit layer of HPF indicated a critical value of the mixing ratio 1/3.5 above which the 700-nm peak is observed. This peak is an indication of a multilayer consisting of pure 1 due to the interlayer interaction. The 560-nm peak observed for LPF is caused by a hindered interlayer interaction of the chromophores between the mixed monolayers.
  • Ryuichi Arakawa, Yozaburo Yoshikawa
    1987 Volume 60 Issue 8 Pages 2743-2746
    Published: 1987
    Released: June 27, 2006
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    The unimolecular dissociations of the C3H7O+ ions produced by the dissociative ionization of t-butyl and s-butyl alcohols have been studied by means of trapped ion mass spectrometry(TIMS). The metastable peak intensities for two competing formations of C3H5+ and CH3O+ have been measured for the ion lifetimes of 0–50 μs. Also, the shifts of the electron-ionization-efficiency(EIE) curves for these ions have been observed between the ion-storage times of 2 and 800 μs. These data have then been fitted by means of QET model calculations. The dissociation paths of C3H7O+ can be interpreted without any assumption of a ratedetermining isomerization process.
  • Hideo Matsumura, Tsutomu Watanabe, Kunio Furusawa, Seiichi Inokuma, Ts ...
    1987 Volume 60 Issue 8 Pages 2747-2750
    Published: 1987
    Released: June 27, 2006
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    The binding behavior of metal ions to the monolayers of a crown ether compound has been studied by the surface potential measurements. The obtained data are analyzed from the viewpoint of interfacial electrochemistry, i.e., the electrical double layer theory at the interfaces. The analysis reveals that the generated double layer at a membrane–solution interface after the complexing of metal ions with crown ethers is well described by the Stern model for the electrical double layer; it shows that there exists a possibility to evaluate the binding constants of metal ions with crown ethers under interfacial circumstances.
  • Masatoshi Hirayama, Hiroshi Ohhata
    1987 Volume 60 Issue 8 Pages 2751-2756
    Published: 1987
    Released: June 27, 2006
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    The diamagnetic monomer dianion of fluorenone was prepared from 1,2-dimethoxyethane solution of neutral molecule in contact with excess sodium metal at −5 °C for 5 days and its 1H and 13C NMR spectra were measured. The possibility that a pinacolate-type dimer dianion occurs in an equilibrium system was ruled out from reactivity with oxygen, water, deuterium oxide, and reducible aromatics in addition to the analysis of NMR spectra. The charge density distribution of neutral and dianion molecules was estimated by MO calculations. Comparison between experimental and theoretical 13C shifts suggested a strong interaction of sodium ions with carbonyl group. It is presumed that an anormalous diamagnetic ring current in 14π-peripheral structure is responsible for poor correlation between theoretical and observed 1H shifts.
  • Yusaku Takita, Fumiaki Hori, Noboru Yamazoe, Tetsuro Seiyama
    1987 Volume 60 Issue 8 Pages 2757-2762
    Published: 1987
    Released: June 27, 2006
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    The effects of the addition (10 atomic%) of lanthanoid oxides into Co3O4 on the oxidation of methyl ethyl ketone (MEK) were studied. The addition of La2O3 brought about marked enhancement of the rate of biacetyl (BA) formation. MEK conversion increased by a factor of 2.8 and the BA selectivity was improved at 450–500K owing to the suppression of deep oxidation. The addition of CeO2 much improved the MEK conversion but BA selectivity decreased to less than 50% and the scission reaction leading to acetaldehyde and acetic acid was enhanced. The addition of Pr6O11 improved MEK conversion but the addition of Nd2O3, Gd2O3, or Er2O3 showed little effect on MEK conversion. The reduction of both scission reaction and deep oxidation and the compensative increase in BA selectivities were observed. An approximately linear relationship was found between the specific rate of BA formation of the catalysts and logarithmic solubitity product constants of hydroxides of tervalent lanthanoid elements added, suggesting that the basicity of the catalysts is one of major factors for BA formation. The maximum efficiency (23.4%) of BA formation was attained at a La content of ca. 10 at.%.
  • Kazuaki Harata
    1987 Volume 60 Issue 8 Pages 2763-2767
    Published: 1987
    Released: June 27, 2006
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    Crystal structure of uncomplexed γ-cyclodextrin, C48H80O40·14.1H2O, was determined by the X-ray method. The crystal is monoclinic and the space group is P21 with cell dimensions; a=16.847(2), b=11.098(2), c=20.271(2) Å, and β=104.97(1)°. The structure was solved by the inspection of a Patterson map and the R-map method combined with the rigid-body least-squares technique and refined by the block-diagonal least-squares method to the R-value of 0.061 for 5099 reflections (sinθ⁄λ≥0.57). γ-Cyclodextrin is in a round shape and somewhat distorted from the regular octagonal symmetry. Intramolecular hydrogen bonds are formed between adjacent glucose residues and maintain the round structure of γ-cyclodextrin. γ-Cyclodextrin molecules are arranged in a cage-type packing, and 7.1 water molecules, occupying 14 sites, are located within the host cavity.
  • Masayoshi Maehara, Sekiichiro Nakama, Yoshinori Nibu, Hiroko Shimada, ...
    1987 Volume 60 Issue 8 Pages 2769-2774
    Published: 1987
    Released: June 27, 2006
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    An assignment of the normal vibrations of 2-aminopyrimidine was made through the vibrational analyses of the polarized Raman and infrared spectra and also through the normal coordinate calculation. The assignment was confirmed by the same study made on 2-amino-d2-pyrimidine.
  • Chiyoko Nakazato, Ryoji Murayama, Masayoshi Aoki, Takahiro Masuda
    1987 Volume 60 Issue 8 Pages 2775-2778
    Published: 1987
    Released: June 27, 2006
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    Radiolysis of methanol adsorbed on synthesized zeolite was investigated by means of product analysis. Molecular hydrogen, formaldehyde, and ethylene glycol are produced as major products. The G-value for the formation of H2 increases with increasing amount of methanol adsorbed on zeolite and approaches ca. 2.1 at about 10−2 mol of methanol per g of zeolite, where the coverage of methanol is approximately unity and G-values of ca. 1.0 are observed for formaldehyde and ethylene glycol. Addition of an electron scavenger causes decrease in G(H2). However, the hydrogen formation is not completely suppressed by N2O, SF6, or CCl4. Kinetics in solution is useful for the interpretation of results and allows the estimation of the G-value for the generation of electron in zeolite and of its relative reactivity toward methanol and some electron scavengers.
  • Yukio Yoshida, Sadakatsu Nishikawa
    1987 Volume 60 Issue 8 Pages 2779-2783
    Published: 1987
    Released: June 27, 2006
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    Ultrasonic absorption and velocity were measured in aqueous solutions of propylamine at 25 °C both in the absence and in the presence of 2 g dm−3 PVA(poly(vinyl alcohol)), 5 mol dm−3 urea and 1 mol dm−3 NaCl. No excess absorption was observed in these solutions without propylamine. A single relaxational absorption was observed in the concentration range from 0.0196 to 0.719 mol dm−3 of propylamine both in the presence and absence of the additives. The ultrasonic parameters have been found to be quite dependent on the concentration of propylamine and also on the structure of additives. This relaxational absorption has been attributed to the perturbation of an equilibrium associated with a proton-transfer reaction. The rate constants and the standard volume change of the reaction have been determined from the concentration dependences of the relaxation frequency and the maximum excess absorption per wavelength. As a result, it was discovered that the forward rate in a solution with PVA increased and those with urea and NaCl, on the other hand, decreased; also, the standard volume change associated with the reaction increased in a series of the solutions with urea, no additive, NaCl, and PVA. The data have been interpreted by means of the structural changes of the solvent water.
  • Sadakatsu Nishikawa
    1987 Volume 60 Issue 8 Pages 2785-2789
    Published: 1987
    Released: June 27, 2006
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    In order to investigate the effect of ionic surfactant on the dynamic properties of nonelectrolyte aqueous solutions, the ultrasonic absorption, velocity and the conductivity have been measured for aqueous solutions of triethylene glycol monobutyl ether (TGBE) in the presence of sodium dodecyl sulfate (SDS) at 25 °C. In aqueous solution of TGBE, a clear single relaxational ultrasonic absorption is observed in the MHz frequency range. When SDS is added the relaxation process is observed in the more dilute solutions, the relaxation frequency shifts to lower frequency and the amplitude of the excess absorption increases in the TGBE concentration range of less than 1.0 mol dm−3. Further, for TGBE concentration greater than 1.0 mol dm−3, the relaxation frequency is found to be almost independent of SDS concentration and the amplitude of the excess absorption decreases with increasing SDS concentration. The observed relaxation is well accounted for by a kinetic scheme involving the interaction between the nonelectrolyte and water. From the concentration dependence of TGBE, the rate and thermodynamic parameters have been determined as a function of SDS concentration. The obtained data have been interpreted in terms of the structural changes of the solvent water by SDS molecules. As the results, it has been proposed that the hydrophobic parts of SDS have a considerable effect on water structure.
  • Hirotoshi Ito, Yasumasa J. I’Haya
    1987 Volume 60 Issue 8 Pages 2791-2801
    Published: 1987
    Released: June 27, 2006
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    An approach to extend the Fano–DeVoe model is presented for copolymer systems by making use of the Green’s operator method within the dipole–dipole approximation. We derive a model Hamiltonian for a system by expanding its primitive Hamiltonian in terms of a bare complete basis set consisting of zero-order one-site and two-site excitation states in the first-order perturbation theory. A generalized extension of the Fano–DeVoe theory can be given by the polarizability tensor derived for this model Hamiltonian. As a more refined way, we derive another model Hamiltonian by expanding the primitive Hamiltonian of the system in terms of the corrected complete basis set consisting of the first-order excitation states. With such model Hamiltonians, we can fabricate polarizability theories on the same footing with the exciton wave function approaches based on the usual perturbation theory. Simplified schemes for the latter model Hamiltonians are applied to the copolymer system consisting of such chromophores that have permanent dipole moments in their ground states. Even if the constituent chromophores do not have permanent moments, extension of the Fano–DeVoe model is made by allowing for the total polymer ground state wave function corrected in terms of two-site excitation states. To circumvent the deficiency of the dipole approximation in the region of short separations of submolecules, we show a recipe as to how to make use of the monopole approximation together with the dipole approximation in conformity with the compromized idea of Moffitt.
  • Kazunaka Endo, Kyonosuke Yamamoto, Kenzo Deguchi, Kazuhiro Matsushita
    1987 Volume 60 Issue 8 Pages 2803-2807
    Published: 1987
    Released: June 27, 2006
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    In an aqueous solution, 63Cu chemical shielding order ([CuCl4]3− \simeq[CuBr4]3−<[CuI4]3−) and line widths (10 to 30 kHz) for CuX–KX systems(where X=Cl, Br, I) have been obtained. The chemical shift(−694 ppm) between [CuCl4]3− and [Cu(CN)4]3− is interpreted by the paramagnetic term which depends mainly upon a 3d-hole on a Cu(I) atom by using perturbation theory with an average excitation energy approximation. The linebroadening of Cu(I) halide complexes in aqueous solution is explained dominantly by a Cu(I) nuclear quadrupole interaction with the electric field gradient which arises from a 3d-hole on a Cu atom. For the abnormal increasing metal shielding order of [MX4](4−i)−([MCl4](4−i)−[MBr4](4−i)−<[MI4](4−i)−), a possibility of the heavyatom effect in the metal shielding of [CuI4]3−(649 ppm, using the lowest excitation energy of the diatomic molecule) and [CdI4]3−(1941 ppm using the lowest excitation energy of the diatomic molecule), is evaluated.
  • Kenji Murao, Kazuhiro Suzuki
    1987 Volume 60 Issue 8 Pages 2809-2816
    Published: 1987
    Released: June 27, 2006
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    Bilayer electrodes, Pt/poly-1/polythiophene [1: tris(4-vinyl-4′-methyl-2,2′-bipyridine)ruthenium(II) perchlorate], where polythiophene is derived from poly(3-methylthiophene) [poly(3-methyl-2,5-thienylene), abbreviated as PMeT] and poly(2,2′-bithiophene) [poly(2,2′-dithienyl-5,5′-ene), abbreviated as PBT], have been prepared. Electropolymerizations of MeT and BT at Pt/poly-1 occur at the platinum electrode surface, followed by phase separation of the polymer components which results in the bilayer structure. Significant imbalance, observed between charge densities involved in the cathodic and anodic waves of the cyclic voltammogram for Pt/poly-1/PBT, is explained as being due to the positive charge leakage from the PBT layer to the platinum substrate through the 2+/3+ redox level of the intervening poly-1 during the potential sweep in the negative direction. This charge leakage is ascribed to the consequence of the closely located oxidation potential of PBT to that of the 2+/3+ of poly-1 (E°′=+0.875 V vs. Ag/Ag+). Time-resolved in situ reflection spectra taken at Pt/poly-1/PMeT immersed in electrolytic solutions give evidence for the mediated redox reactions of PMeT by the poly-1 layer. The spectral changes strongly suggest the transient occurrence of polarons during the doping process.
  • Toshiharu Kano, Kiyoshi Nishikawa, Shigeyuki Aono
    1987 Volume 60 Issue 8 Pages 2817-2823
    Published: 1987
    Released: June 27, 2006
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    Intermolecular interactions are analyzed by the propagator method, under the tight-binding approximation. The stabilization energy or the change of charge density due to the intermolecular interaction are expressed in terms of propagators, so that the mechanism resulting above effects is satisfactorily realized. As an interesting example, the intermolecular interaction between guanine and benzo[a]pyrene (a famous chemical carcinogen) is investigated.
  • Kiyomi Okabe, Etsuro Kobayashi
    1987 Volume 60 Issue 8 Pages 2825-2831
    Published: 1987
    Released: June 27, 2006
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    The possibility of the hydrothermal synthesis of layered zirconium phosphates containing various alkaline earth metals (abbreviated as ZrMP; M=Mg, Ca, Sr, Ba) has been studied from ZrOCl2 and M(HPO4)2, and their characteristics have been investigated. The optimum conditions for the synthesis of a highly crystalline product were as follows; the molar ratio of the starting materials of Ca(H2PO4)2 and ZrOCl2 was Ca/Zr=3, and the temperature of the hydrothermal reaction was in the range of 200–270 °C. By the hydrothermal reaction of ZrOCl2 and Mg(H2PO4)2, a new compound of ZrMg0.5H(PO4)2·H2O with a layer-spacing of 11.94 Å was obtained. Layered phosphate (ZrMP) was not obtained by the hydrothermal reaction of ZrOCl2 and Ba(H2PO4)2. The temperature range of the inter-layer dehydration of the layered phosphates (ZrMgP, ZrCaP, and ZrSrP) was similar to that of α-zirconium(IV) bis(hydrogenphosphate) (α-ZrP); i.e. the water in the interlayer was lost at 130–240 °C, and dehydro-condensation took place at a higher temperature above 340 °C. Zirconium phosphate containing Mg2+ or Ba2+ was not obtained by the ion exchange of the protons in α-ZrP with the alkaline earth metal cations (M2+) in MCl2, while Ca2+ and Sr2+ were exchanged with the protons. These alkaline earth metal ions except for Ba2+ were easily exchanged with H+ in α-ZrP, when NaOH was added. The layer-spacing of the Mg2+-exchanged zirconium phosphate was 9.6 Å, which was different from that of the hydrothermal product. The layer distances of Ca2+- or Sr2+-exchanged products were similar to those of the hydrothermal products.
  • Susumu Okazaki, Akito Kurosaki
    1987 Volume 60 Issue 8 Pages 2833-2837
    Published: 1987
    Released: June 27, 2006
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    For a surface modification, fluorinations of silica samples including a quartz fiber and a commercial glass fiber, were carried out at around 500 °C in a conventional flow reactor. The surface compositions before and after the fluorination were determined by XPS analyses. Among chlorofluoromethanes and CF4, CCl3F was the most effective for fluorination. Surface OH groups were completely removed or replaced by the fluorination. Adsorptions of water vapor, hexane, hexafluoropropene, and octafluorocyclobutane showed that the silica surface became more hydro- and lipophobic after the fluorination. On the contrary, the chlorofluoro-methanetreated surface exhibited a higher affinity to the perfluorocarbons compared to the untreated surface.
  • Toshishige M. Suzuki, Osamu Itabashi, Tomio Goto, Toshiro Yokoyama, Te ...
    1987 Volume 60 Issue 8 Pages 2839-2842
    Published: 1987
    Released: June 27, 2006
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    A new adsorbent containing an iminodiacetate group has been prepared by the surface modification of a polymer-coated silica gel. The obtained beads (SG–IDA) are porous and have a high specific surface area (≈350 m2 g−1). The adsorption properties of SG-IDA, including the adsorption capacities, equilibrium distribution coefficients (Kd) and adsorption rates, have been examined for divalent metal ions. The selectivity order of SG–IDA is Cu(II)>Pb(II)>Ni(II)>Zn(II)>>Ca(II)>Mg(II). The SG–IDA shows appreciably high Kd values and rapid kinetics toward the adsorption of heavy metal ions. The concentration of 10 ppb level of metal ions [Cu(II), Zn(II), and Cd(II)] has been demonstrated using the SG-IDA column.
  • Kunio Ohtsuka, Johji Koga, Mitsuru Suda, Mikiya Ono, Minoru Takahashi
    1987 Volume 60 Issue 8 Pages 2843-2847
    Published: 1987
    Released: June 27, 2006
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    Cobalt(II) hydroxide–(sodium fluoride tetrasilicic mica) intercalation complexes were prepared by titrating cobalt(II) nitrate solutions in the presence of mica with sodium hydroxide under oxygen-free conditions. These complexes were characterized by chemical analysis, XRD, DTA-TGA, IR, and surface area measurements. These confirmed that the brucite-like cobalt(II) hydroxide sheet developed within the interlayer of the silicate. Cobalt atoms reduced at 400–700 °C by H2 migrated from the interlayer of the silicate to the external surface of these where highly dispersed cobalt particles were formed. Ultra-fine cobalt metals (50–200 Å) with a hexagonal close-packed form were prepared at 400 °C by H2. The degree of reduction and the grain diameter of cobalt increased with an increase of the reducing temperature and/or the reducing time.
  • Yoneichiro Muto, Michio Nakashima, Tadashi Tokii, Michinobu Kato, Ikuo ...
    1987 Volume 60 Issue 8 Pages 2849-2852
    Published: 1987
    Released: June 27, 2006
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    Dimeric copper(II) trichloroacetate adducts with 3-substituted pyridines, [Cu(Cl3CCOO)2(3-Xpy)]2 where X=Cl, Br, H, CN, and CH3, have been prepared. Magnetic susceptibility and ESR data show that both the singlet–triplet separation (−2J) and the zero field splitting (D) decrease in the order: 3-Clpy adduct (193 and 0.397 cm−1)≈3-Brpy adduct (191 and 0.399 cm−1)>py adduct (188 and 0.385 cm−1)>3-CNpy adduct (138 and 0.216 cm−1)>3-CH3py adduct (83 and 0.182 cm−1). Electronic spectra indicate that the adducts with X=Cl, Br, and H have a distorted square-pyramidal copper(II) geometry and that those X=CN and CH3 have a distorted trigonalbipyramidal geometry. Form these results, it is concluded that the strength of antiferromagnetic interaction in [Cu(Cl3CCOO)2(3-Xpy)]2 complexes decreases as the distortion of copper(II) geometry increases from squarepyramid toward trigonal-bipyramid.
  • Akihiro Kawaguchi, Shin-ichi Magaino, Takashi Suzuki, Yasushi Takeuchi
    1987 Volume 60 Issue 8 Pages 2853-2856
    Published: 1987
    Released: June 27, 2006
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    An isotachophoretic analysis and electromigration of ions through a cation-exchange membrane have been investigated. K, Li, Na, and Cu ions were migrated at a constant current. The potential difference between fibrous ion exchanger and cathode reservoir was measured during migration of ion zone. The relative ionic mobility of K+, Na+, Li+, and Cu2+ calculated by potential difference was 1, 0.667, 0.420, and 0.218, respectively. The concentration of mobile cations in unit volume of the membrane was calculated by the amount of migration and the migration time of each ion. The concentration of mobile Li+ in the Li zone was about 10% lower than that of mobile K+ in the K zone. This difference in concentration is similar to the result by the usual isotachophoresis using a capillary tube. The migration time of each ion zone through detection part was proportional to the amount of migration. K+ and Li+ in the concentration range from 0.6×10−3 to 0.2 mol dm−3 were quantitatively determined by the migration time with reproducible errors less than ±5 %.
  • Genichiro Kura
    1987 Volume 60 Issue 8 Pages 2857-2860
    Published: 1987
    Released: June 27, 2006
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    The hydrolysis rates of inorganic cyclo-polyphosphates in alkaline solutions were determined. The rates in a NaOH solution were significantly faster than those in a (CH3)4NOH solution. Ion-pair formation between PO and Na+ renders the P atom more positive by reducing the electron density around the atom and more susceptible to the nucleophilic attack by OH. In a (CH3)4NOH solution, higher-membered cyclo-polyphosphates with a larger ring structure became rather stable. Arrhenius’ activation energy for each phosphate decreases in the order HCl>NaOH>(CH3)4NOH.
  • Tsuyoshi Nomura, Genkichi Nakagawa
    1987 Volume 60 Issue 8 Pages 2861-2864
    Published: 1987
    Released: June 27, 2006
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    The properties of alkali-free lead phosphate glasses containing silver oxide as an anion selective electrode were examined, and their application to a potentiometric detector for an ion chromatographic technique were developed. The series of these glasses are characterized by their low softening temperature and are only responsive to anionic substances. The featureless potential response of almost anions tested becomes a rather useful property as a detector for an ion chromatographic analysis of anions. The response characteristics and selectivity coefficients revealed that the glass composition of 10Ag2O : 55P2O5 : 25PbO : 10Al2O3 is the most suitable electrode materisl for anion chromatography. With this glass electrode, nonsuppressed anion chromatographic parameters were studied, including a comparison of an eluent composition, the flow rate and the retention time. This detector could be used in a high pH eluent without any interference of the large blank value. In paticular, the detector was highly sensitive to iodide ions. This may be due to the interaction of iodide ions with silver ions which are involved in membrane materials.
  • Shin-ichi Ishiguro, László Nagy, Hitoshi Ohtaki
    1987 Volume 60 Issue 8 Pages 2865-2869
    Published: 1987
    Released: June 27, 2006
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    Formation equilibria of ternary zinc(II) complexes with chloride ions and 2,2′-bipyridyl (bpy) have been calorimetrically studied in N,N-dimethylformamide (DMF) containing 0.4 mol dm−3 (C2H5)4NClO4 as a constant ionic medium at 25 °C. Formation of binary (2,2′-bipyridyl)zinc(II) complexes has also been explored. The calorimetric data were satisfactorily explained in terms of formation of the ternary [ZnCl(bpy)]+ and [ZnCl2(bpy)] complexes together with the binary [Zn(bpy)n]2+ (n=1–3) ones, and their formation constants and enthalpies were determined. The formation of the ternary [ZnCl(bpy)]+ and [ZnCl2(bpy)] complexes is not so favorable in DMF. It is suggested that both [ZnCl(bpy)]+ and [ZnCl2(bpy)] complexes have the four-coordinate tetrahedral structure in DMF.
  • Goutam De, Masatatsu Suzuki, Akira Uehara
    1987 Volume 60 Issue 8 Pages 2871-2874
    Published: 1987
    Released: June 27, 2006
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    Solid-state thermal reactions of trans- and cis-[Cr(NCS)2(AA)2]SCN where AA is 1,2-ethanediamine (en) or 1,3-propanediamine (tn) were studied. Upon heating, both the cis- and trans-complexes lost half mole of diamine to convert into the double complex trans-[Cr(NCS)2(AA)2][Cr(NCS)4(AA)]. The anion moiety [Cr(NCS)4(AA)] was isolated from the double complex. The thermal reactions are thus useful for easy preparation of [Cr(NCS)4(AA)] complex, which has previously been obtained with difficulty from solution reactions.
  • Ken-ichi Okamoto, Hideki Umehara, Jinsai Hidaka
    1987 Volume 60 Issue 8 Pages 2875-2879
    Published: 1987
    Released: June 27, 2006
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    The cis-α isomers of the 3,6-diazaoctane-1,8-diamine (trien) cobalt(III) complexes with 1,3-propanedithiolate (pdt) and 1,3-propanedisulfinate (pdsi) were selectively prepared and optically resolved. Of these isomers, the crystal structure and the absolute configuration of (−)460CD-[Co(pdsi)(trien)]ClO4·H2O have been determined by X-ray diffraction method. The complex cation takes a Δ-cis-α configuration. The 1,3-propanedisulfinate coordinates to cobalt atom through two sulfur atoms and its chelate ring takes a skew boat form with the λ conformation. The CD spectral behaviors in the d–d transition and the sulfur-to-metal (Co(σ*)←S(σ)) charge-transfer band regions are discussed in relation to the absolute configurations of the cobalt(III) complexes with sulfinate type sulfur donor atoms and the corresponding thiolate ones.
  • Masashi Otsuka, Takeshi Fujiyama, Yoshikazu Tsukamoto, Hideyasu Tsuiki ...
    1987 Volume 60 Issue 8 Pages 2881-2885
    Published: 1987
    Released: June 27, 2006
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    A radial distribution of cobalt metal particles in an alumina sphere was controlled by impregnation of the spheres with a solution composed of cobalt nitrate dissolved in ethylene glycol, ethyl silicate, and a small amount of nitric acid. The radial position of cobalt narrow band in the sphere was varied with the impregnation time and the cobalt loading was controlled by the concentration of cobalt nitrate in the impregnation solution. It was also found that porous SiO2 film resulted from the gelling of ethyl silicate covered whole external surface of the sphere.
  • Tetsuaki Nishida, Michiko Ogata, Yoshimasa Takashima
    1987 Volume 60 Issue 8 Pages 2887-2889
    Published: 1987
    Released: June 27, 2006
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    Distinct decreases in the quadrupole splitting of the tetrahedral Fe3+ ions and the Tg suggest a gradual change from the layer structure composed of the VO5 tetragonal pyramids to the chain structure composed of the VO4 tetrahedra. It is also concluded that nonbridging oxygen atoms are present in the VO4 tetrahedra.
  • Isao Ono, Norisuke Hata
    1987 Volume 60 Issue 8 Pages 2891-2897
    Published: 1987
    Released: June 27, 2006
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    The photochemical reactions of the quinoline derivatives substituted by an ethoxycarbonyl group at the 2-, 3-, and 4-positions of a quinoline nucleus have been investigated in several alcohols and cyclohexane. Irradiation of ethyl 4-quinolinecarboxylate (1) yielded ethyl 2-hydroxyalkyl-4-quinolinecarboxylates (4a–c) in alcohols and ethyl 2-cyclohexyl-4-quinolinecarboxylate (4d) in cyclohexane in a good yield, respectively. The photochemical reactions of ethyl 3-quinolinecarboxylate (2) showed remarkable solvent dependency. Irradiation in methanol and cyclohexane afforded a solvent-additive product, ethyl 4-hydroxymethyl-1,4-dihydro-3-quinolinecarboxylate (5a) and ethyl 4-cyclohexyl-1,4-dihydro-3-quinolinecarboxylate (5b), while such photoaddition of the solvent did not proceed in ethanol and 2-propanol but instead ethyl 1,4-dihydro-3-quinolinecarboxylate (6) and dimeric compounds were formed, both of which were unstable and finally reverted to 2 at room temperature in air. In the case of ethyl 2-quinolinecarboxylate two types of the products, ethyl 4-hydroxyalkyl-1,4-dihydro-2-quinolinecarboxylate (7) and ethyl 1,4-dihydro-2-quinolinecarboxylate (8) were obtained in ethanol and 2-propanol but the yields of those products were poor. On the basis of triplet quenching experiments, the photochemical reactions of those ethyl quinolinecarboxylates are suggested to occur through hydrogen abstraction from the solvents by the ring nitrogen in the S1 state.
  • Akira Tsuchida, Masahide Yamamoto, Yasunori Nishijima
    1987 Volume 60 Issue 8 Pages 2899-2903
    Published: 1987
    Released: June 27, 2006
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    The photocycloaddition reaction of N-vinylcarbazole (VCZ) as an electron donor, with 3-cyanostyrene as an electron acceptor, was studied. In nonpolar solvents, two cyclobutanes of cis-1-(9-carbazolyl)-2-(3-cyanophenyl)cyclobutane and trans-1-(9-carbazolyl)-2-(3-cyanophenyl)cyclobutane (in a ratio of 3 : 1) were obtained from an exciplex intermediate. The structure of cis cyclobutane seemed to originate from a sandwich conformation of the exciplex. In polar solvents, a photodissociation to free ion radicals was observed and trans-1,2-di(9-carbazolyl)cyclobutane was produced efficiently by means of a chain mechanism via a cation radical of VCZ. Transient intermediates were measured by means of nanosecond laser photolysis; the results supported the reaction scheme.
  • Hiroyoshi Kamogawa, Tsuneharu Kasai, Toshio Andoh, Tomoyuki Nakamura
    1987 Volume 60 Issue 8 Pages 2905-2909
    Published: 1987
    Released: June 27, 2006
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    Azoxy compounds bearing a 2,5-disubstituted pyridine ring as a principal constituent and at least one alkyl group at a molecular end were synthesized and their mesomorphic (nematic) ranges were examined. As for azoxy compounds containing an alkyl and an alkoxy group at both ends, respectively, mesomorphic ranges appeared with lower alkyl groups than those for azo compounds, their precursors. The ranges were also lower than those with both alkoxy ends. As regards an azoxy compound containing alkyl groups at both ends, no mesomorphic phenomenon appeared within the scope of this study.
  • Takashi Sakai, Kazuhiko Kohda, Sadao Tsuboi, Masanori Utaka, Akira Tak ...
    1987 Volume 60 Issue 8 Pages 2911-2915
    Published: 1987
    Released: June 27, 2006
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    The stereoselective dehydration of 5-(2-hydroxyalkyl)-3(2H)-furanones is accomplished conveniently by the treatment with Me3SiCl in acetonitrile to give 5-[(E)-1-alkenyl]-3(2H)-furanones.
  • Sadao Tsuboi, Hiroshi Wada, Koichi Muranaka, Akira Takeda
    1987 Volume 60 Issue 8 Pages 2917-2921
    Published: 1987
    Released: June 27, 2006
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    Heating of 3,5-disubstituted 4-bromo-3-methoxycarbonyldihydro-2(3H)-furanones with NaI in 3-pentanone gave 3,5-disubstituted 2(5H)-furanones in 55.8–93.3% isolated yields. A total synthesis of (±)-acarenoic acid was established in 33% overall yield via 4 steps.
  • Mutsuji Sakai, Nobuo Hirano, Fumiya Harada, Yasumasa Sakakibara, Norit ...
    1987 Volume 60 Issue 8 Pages 2923-2926
    Published: 1987
    Released: June 27, 2006
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    1,4-Cyclohexadiene was hydrogenated selectively to cyclohexene with a nickel catalyst generated from bis(acetylacetonato)nickel(II), triethyldialuminium trichloride, and triphenylphosphine at 40 °C under an atmospheric pressure of hydrogen. The hydrogenation of eleven kinds of alkyl-substituted 1,4-cyclohexadienes gave the corresponding cyclohexenes in good yields by the nickel catalyst. The structural factors of the alkyl substituent on the diolefin are shown to affect the hydrogenation rate. The homogeneous nickel catalyst system, in which a nickel hydride complex NiH(PPh3)(AlCl4) is supposed to be an active species, was effective for the selective hydrogenation of the diolefin to the olefin. A plausible pathway involving π-allylnickel complexes for the hydrogenation is proposed.
  • Yasuhiro Tanoue, Akira Terada, Toshiyuki Tsuboi, Takayuki Hayashida, O ...
    1987 Volume 60 Issue 8 Pages 2927-2930
    Published: 1987
    Released: June 27, 2006
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    6-Formyl- and 6-hydroxymethyl-5,8-dihydroxy-2-methoxy-1,4-naphthoquinones were, respectively, prepared from 2-formyl- and 2-hydroxymethyl-1,4,5,6,8-pentamethoxynaphthalenes which were synthesized as key intermediates of the new antibiotics containing 2-methoxynaphthazarin structure.
  • Yoshinobu Nagawa, Koichi Honda, Hiroshi Nakanishi
    1987 Volume 60 Issue 8 Pages 2931-2935
    Published: 1987
    Released: June 27, 2006
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    The first 1,8-diheteroaromatic naphthalenes, 1,1′-(1,8-naphthylene)di-1H-1,2,3-triazoles (1), were synthesized by 1,3-dipolar cycloadditions of 1,8-diazidonaphthalene to acetylenic esters. The spectral properties of these compounds were studied and compared with those of the corresponding 1-(1-naphthyl)-1H-1,2,3-triazoles (2). The two triazole rings at the peri-positions in 1 are in a face-to-face arrangement according to the results of 1H NMR spectra. The UV spectra of 1 are almost identical with each other and show a red shift from those of corresponding 2. No significant spectral differences between 1 and 2 were observed in the IR spectra. The fragment ion with two azirine groups at the peri-position in the naphthalene ring was observed in the MS spectra of 1.
  • Tatsuo Arai, Takahisa Oguchi, Toshio Wakabayashi, Masahiro Tsuchiya, Y ...
    1987 Volume 60 Issue 8 Pages 2937-2943
    Published: 1987
    Released: June 27, 2006
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    The quantum yields for norbornadiene(N)→quadricyclane(Q) and Q→N isomerization were determined in acetonitrile using several substituted benzophenones (BPs) as triplet sensitizers. For the N→Q isomerization, BPs with electron-donating substituents exhibited higher quantum efficiency (0.4–0.6) than BPs with electronaccepting substituents. The quantum yields for Q→N isomerization increased with electron-accepting ability of the substituents on BPs, but were lower than 0.1. The rate constants for quenching of triplet BPs by N and Q were also determined in acetonitrile by means of laser flash photolysis. The rate constants for N were not dependent on the triplet energies (ET) of BPs but dependent on electronic properties of the substituents on BPs. On the contrary, those for Q increased with decreasing ET of BPs and with increasing Hammett’s σ constants of the substituents of BPs. Based on these observations an addition-elimination process is proposed for the N→Q isomerization, and an electron transfer process for the Q→N isomerization.
  • Hiroyuki Ohno, Shinji Takeoka, Eishun Tsuchida
    1987 Volume 60 Issue 8 Pages 2945-2951
    Published: 1987
    Released: June 27, 2006
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    1,2-Di-O-(2,4-octadecadienoyl)-sn-glycero-3-phosphorylcholine is polymerized by radical initiators. An azobisisobutyronitrile (AIBN) and an azobis(2-amidinopropane) dihydrochloride (AAPD) are incorporated into hydrophobic membrane region of the lipid liposomes and an aqueous medium, respectively by sonication. The use of either AIBN or AAPD gives polymerization conversion of about 50% at 60 °C. This is not improved by the elongation of polymerization period at 60 °C or the increase of the amount of these radical initiators. The lyophilized lipids thus polymerized by either AIBN or AAPD are soluble in methanol suggesting the formation of linear polymers. Simultaneous polymerization by both AIBN and AAPD provides almost complete polymerization. AIBN and AAPD have been suggested to initiate radical polymerization of diene groups in 1- and 2-acyl chains, respectively. Potassium peroxodisulfate, another water-soluble radical initiator, yields polymerized liposomes with polymerization conversion of more than 80%. This corresponds to the polymerization of diene groups of not only 2- but also 1-acyl chains due to the hydroxyl radicals which are generated by the radial transfer in an aqueous medium. These different initiation reactions are attributed mainly to the unequivalent chemical environment of diene groups in 1- and 2-acyl chains.
  • Masao Hisatome, Masamichi Yoshihashi, Koji Yamakawa, Yoichi Iitaka
    1987 Volume 60 Issue 8 Pages 2953-2962
    Published: 1987
    Released: June 27, 2006
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    [2]Metacyclo- and [2]paracyclo[2](1,3)ferrocenophanes (1 and 2) have been synthesized and characterized by means of X-ray diffraction and spectroscopy. The crystal data of the phanes were determined as follows: 1, monoclinic, P21 a=8.851(4), b=15.742(8), c=5.963(3) Å, β=109.76(5)°, Z=2; 2, orthorhombic, Pbca, a=15.308(8), b=24.716(12), c=8.034(4) Å, Z=8. The benzene rings of the both phanes are distorted in a similar manner to [2.2]cyclophanes but the planarities of the cyclopentadienyl (Cp) rings are maintained. The distance between the substituted Cp ring and the iron atom in 1 is considerably extended (1.678(4) Å) in comparison with ferrocene, whereas that of 2 (1.659(3) Å) is not. The 2-hydrogen of the Cp ring and the 9-hydrogen of the benzene ring in 1 are situated right above each other’s rings. In the 1H NMR spectrum of 1, the 2- and 9-protons shifted to highfield to a considerable extent (δ1.18 and 5.34, respectively) due to the diamagnetic anisotropic effects of the benzene and Cp rings. The electronic spectra of both phanes exhibited bathochromic shifts of the d–d absorption band of the iron (1, 451 nm, 2, 447 nm) as compared to [3]metacyclo- and [3]paracyclo[3](1,3)ferrocenophanes (each 442 nm), which were synthesized as reference compounds in this work.
  • Yuji Kogami, Kenji Okawa
    1987 Volume 60 Issue 8 Pages 2963-2965
    Published: 1987
    Released: June 27, 2006
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    A convenient synthesis of optically active 3-morpholinecarboxylic acid and its thio analogue, tetrahydro-2H-1,4-thiazine-3-carboxylic acid, has been developed. These intermediates were obtained by reaction of benzyl (S)-N-benzyloxycarbonyl-2-aziridinecarboxylate and its enantiomer with 2-chloroethanol or 2-chloroethanethiol, respectively.
  • Osamu Ito, Hiroyuki Seki, Masashi Iino
    1987 Volume 60 Issue 8 Pages 2967-2975
    Published: 1987
    Released: June 27, 2006
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    The ESR parameters (spin concentration, line width, g-value, and spin-lattice relaxation time) of various coals mined in Japan and in many foreign countries have been measured. Low spin concentrations, broad line widths, and long spin-lattice relaxation times have been recognized as characteristics of Japanese bituminous coals (e.g., Akabira, Miike, and Shin-yubari coals) compared with the foreign coals having similar carbon contents. The origins of these differences were interpreted by the aid of the FT-IR spectra. Low fractions of aromatic carbon and rich aliphatic groups of Japanese bituminous coals are closely related to the characteristics in the ESR parameters.
  • Yôichi Iida
    1987 Volume 60 Issue 8 Pages 2977-2981
    Published: 1987
    Released: June 27, 2006
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    The signals which direct excision of introns from mRNA precursors in higher eukaryotes’ genes are not well-understood. Although a consensus sequence, (Remark: Graphics omitted.), has been proposed with the 5′-splice site, actual 5′-splice site sequences differ from it to a greater or lesser degree. In the present paper, structural analysis of 5′-splice site sequences was done by using quantification theory (class II). Nucleotide sequences were transformed into categorical data, and categorical discriminant analysis was carried out between 5′-splice site sequences and sequences other than 5′-splice site. Relative importance of each position of nucleotide sequence was then estimated by calculating partial correlation coefficient on each position.
  • Hideko Kiriyama, Masao Hashimoto, Nanami Okuno
    1987 Volume 60 Issue 8 Pages 2983-2988
    Published: 1987
    Released: June 27, 2006
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    The crystal structure of the title compound has been determined by means of X-ray diffraction. The crystal data and the final R value are: Cu(CCl3COO)2·3H2O, monoclinic C2⁄c, a=23.082(3), b=6.253(1), c=9.726(2) Å, β=94.67(1)°, Z=4, R=0.049. The structure consists of monomeric Cu(CCl3COO)2(H2O)3 molecules, which are linked together by intermolecular O–H···O hydrogen bonds to form a layer parallel to (100). Each Cu(II) atom is coordinated by five oxygen atoms which form nearly a square pyramid; two oxygen atoms of two carboxylate ions and two water molecules form its basal plane and the remaining water molecule occupies the apical position. The mean basal Cu–O length is 1.961 Å and the apical one 2.183 Å. The Cu(II) atom is displaced from the basal plane by 0.110 Å toward the apical oxygen. Thermal analysis (DSC) disclosed two phase transitions at 163 and 207 K, their estimated molar enthalpies being about 0.4 and 0.7 kJ mol−1, respectively. At 77 K, 24 35Cl NQR signals are observed in the frequency range 38.7–40.3 MHz. The X-ray diffraction photographs for both low-temperature phases indicate the appearance of superstructures with less symmetrical space groups; the b spacing doubles below 207 K, while both b and c spacings double below 163 K.
  • Isao H. Suzuki, Norio Saito
    1987 Volume 60 Issue 8 Pages 2989-2992
    Published: 1987
    Released: June 27, 2006
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    The dependence of ethylene W-value on photon energy has been precisely measured in the region from 269 to 324 eV by using monochromatized synchrotron radiation. The W-value showed an oscillatory variation at the Cls→π* excited state as well as the C–K edge. A model has been proposed in which the inner-shell excitation gives rise to a change in the energy of the electron ejected from the molecule having absorbed a photon. It has been found that the model can reproduce the oscillatory variation feature of the W-value.
  • Bhutnath Karmakar, Prabir K. Chatterjee, Samita Basu, Mihir Chowdhury
    1987 Volume 60 Issue 8 Pages 2993-2995
    Published: 1987
    Released: June 27, 2006
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    Although chiral studies have proved to be handy in the assignment of transitions in biological molecules, organic molecules and transition metal complexes, its potentiality for lanthanoid transition needs to be demonstrated. The paper explores the usefulness of CD studies in the assignment of lanthanoid transitions with two specific chiral single crystals–thulium diglycolate (Tm3+–DG) and terbium diglycolate (Tb3+–DG). It has been shown that chirality can distinguish ΔJ=0, ±1 transition from others. The need for studies under higher resolution has been pointed out.
  • Mirza Aijaz Beg, Mohd. Shakil Kidwai
    1987 Volume 60 Issue 8 Pages 2997-2999
    Published: 1987
    Released: June 27, 2006
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    Extraction of monobasic divalent metal bromo acids in pentyl alcohol–benzene and isopentyl acetate–benzene mixtures was studied at room temperature (25 °C). Three molecules of pentyl alcohol ae well as of isopentyl acetate were associated with each metal acid molecule of cobalt and copper in the organic phase. Zinc, cadmium, and mercury acids take up two molecules of pentyl alcohol and one molecule of isopentyl acetate. Metal acids studied here mostly exist as monomer in the organic phase. In pentyl alcohol, however, copper acid is monomeric only at lower concentrations (4×10−5 to 2×10−4M) and dimeric at higher concentrations (3.3×10−4 to 1.4×10−3M).
  • Tarasankar Pal, Ashes Ganguly, Durga S. Maity
    1987 Volume 60 Issue 8 Pages 3001-3004
    Published: 1987
    Released: June 27, 2006
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    The use of silver–gelatin complex was found suitable for the determination of trace amounts of carbon monoxide in air. Silver–gelatin complex is reduced by carbon monoxide to give intensely colored sol. Measurement of the color intensity of the stable silver sol enables the determination of carbon monoxide successful under various environmental conditions. The detection limit is 2–100 ppm. The relative standard deviation for the determination of 10 ppm carbon monoxide is 2.6%.
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