[en] Novel platinum(IV) complexes with asymmetric chiral diamine ligands cis, cis, trans-A₂PtCl₂(X)₂ (X=OH, OCOCH₃, OCOC₂H₅, A₂=NH₂CH(CH₃)CH₂NH(c-C₆H₁₁)(apcha), NH₂CH(CH₃)CH₂NH(c-C₅H₉)(apcpa)) have been prepared. One of the platinum(IV) complexes, (apcpa)PtCl₂(OCOC₂H₅)₂(6), was subjected to X-ray crystallographic analysis. The crystal structure of (apcpa)PtCl₂(OCOC₂H₅)₂ (monoclinic, P2₁ (No.4), a=9.1391(1), b=22.2517(1), c=10.0687(1) A, β=109.105(1) .deg. , V=1934.80(3) A³, Z=4, R₁=0.0532) exhibits that the platinum atom achieves a typical octahedral arrangement with two nitrogen atoms in cis positions and two carboxylato group in trans positions. The spectroscopic data disclose that these platinum(IV) complexes are stable and their molecular structures are retained in aqueous solution. The title complexes are highly cytotoxic in vitro but do not exhibit oral anticancer activity in vivo

[en] The dipolar effect of neighboring protons that are not directly bonded to the carbon of interest on coupled carbon-13 relaxation in a simple organic molecule has been studied by comparing the relaxation behaviors of labeled carbon-13 Br¹³CH₂COOH with those in BrCH₂¹³COOH. Various pulse sequences, such as coupled inversion recovery pulse sequence, J-negative and J-positive pulse sequence, and nonselective and selective proton π pulse sequence, were employed to perform the required coupled spin relaxation experiments. To gain information on various spectral densities, including that of dipolar-CSA cross correlation, the experiments were performed on two different spectrometers, operating, respectively,at 50.31 and 125.51 MHz for ¹³C. The magnitude of CH dipolar spectral densities for BrCH₂¹³COOH was found to be about 8% of those for Br¹³CH₂COOH, which means the effect due to the protons not directly bonded to the carbon of interest is small but not completely negligible

[en] Ternary (Mo-Ru-Pd) and binary (Mo-Ru-Pd) alloys have been prepared using an Ar arc melting furnace. Mo and the noble metals, Ru and Pd, are the constituents of metallic insoluble residues, which were found in the early days of post-irradiation studied on uranium oxide fuels. In the present study, the structure of the alloys was evaluated using a powder X-ray diffractometer. Unit cell parameters were determined by least squares refinements of powder X-ray diffraction data. Scanning electron microscopic analyses of the surface of the alloys indicated that surface morphology was dependent on the crystallographic structure as well as its composition. Measurements of the magnetic susceptibility of the alloys showed evidence of superconducting transition from 3 to 9.2 K. Among the ternary and binary alloys, the σ-phase showed the highest superconducting transition temperature, ∼9.2 K

[en] The time-dependent tracking inversion method is studied to extract the potential energy surface of the electronic excited state in the photodissociation of triatomic molecules. Based on the relay of the regularized inversion procedure and time-dependent wave packet propagation, the algorithm extracts the underlying potential energy surface piece by tracking the time-dependent data, which can be synthesized from Raman excitation profiles. We have demonstrated the algorithm to extract the potential energy surface of electronic excited state for NO₂ molecule where the wave packet split on a saddle-shaped surface. Finally, we describe the merits of the time-dependent tracking inversion method compared with the time-dependent inversion method and discussed several extensions of the algorithm

[en] Thermodynamic and electrical functions of aminophenol and anthranilic acid complexes with Mn(II), Fe(II), Co(II), Ni(II) and Cu(II) were determined. ΔG^o, ΔH^o and ΔS^o were calculated with the help of stability constant values at different temperatures. It was found that the complexing processes have an exothermic nature. The studied complexes behave like semiconductors. The conduction takes place according to hopping mechanism. To show the composition of complexes conductometric and photometric titrations, IR spectra, thermal analysis and X-ray diffraction techniques were employed

[en] A series of catalysts, NiSO₄/TiO₂, for ethylene dimerization was prepared by the impregnation method using aqueous solution of nickel sulfate. On the basis of the results obtained from X-ray diffraction, the addition of NiSO₄ shifted the transition of TiO₂ from the anatase to the rutile phase toward higher temperatures due to the interaction between NiSO₄ and TiO₂. Nickel sulfate supported on titania was found to be very active even at room temperature. The high catalytic activity of NiSO₄/TiO₂ closely correlated with the increase of acidity and acid strength due to the addition of NiSO₄. It is suggested that the active sites responsible for ethylene dimerization consist of low valent nickel, Ni⁺, with an acid

[en] Good-to-excellent yields of 2,3-Disubstituted norbornenes (or norbornanes) were obtained using a Pd/Cu catalyzed three-component ternary coupling reaction of aryl halides, norbornadiene (or norbornene), and alkynols in toluene at 100 .deg. C in the presence of 5.5 M NaOH as a base and benzyltriethylammonium chloride as a phase transfer catalyst. The results of experiments using various aromatic halides suggest that the ternary coupling reaction is promoted by bromide

[en] Vanadium oxide thin films with thickness of about 2000 A have been prepared by radio frequency sputter deposition using a V₂O₅ target in a mixed argon and oxygen atmosphere with different Ar/O₂ ratio ranging from 99/1 to 90/10. X-ray diffraction and X-ray absorption near edge structure spectroscopic studies show that the oxygen content higher than 5% crystallizes a stoichiometric V_O5 phase, while oxygen deficient phase is formed in the lower oxygen content. The oxygen content in the mixed Ar + O₂ has a significant influence on electrochemical lithium insertion/deinsertion property. The discharge-charge capacity of vanadium oxide film increases with increasing the reactive oxygen content. The V_O5 film deposited at the Ar/O₂ ratio of 90/10 exhibits high discharge capacity of 100 μAh/cm²-μm along with good cycle performance

[en] Computations are presented for the ortho- and para-substituted benzyl alcohol-H₂O clusters. A variety of conformers are predicted, and their relative energies are compared. Binding energies of the clusters are computed, and detailed analysis is presented on the effects of substitution on the strength of the hydrogen bond in the clusters. F-and NH₂-substituted clusters are studied to analyze the effects of electron-withdrawing and electron-pushing groups. In para-substituted clusters, the inductive effects are dominant, affecting the binding energies in opposite way depending on whether the hydroxyl group is proton-donating or -accepting. For ortho- substituted cluster, more direct involvement of the substituting group and the resulting geometry change of the hydrogen bond should be invoked to elucidate complicated pattern of the binding energy of the clusters

[en] The non-spectroscopic interference effects that occurred in inductively coupled plasma/mass spectrometry were studied for Ge, As and Se in human urine and serum. Many biological samples contain Na, K, Cl and organic compounds, which may cause the enhancement and depression on the analyte signal. The effect of 1% concomitant elements such as N, Cl, S, P, C, Na, and K on a 100 μg/L germanium, arsenic and selenium signal has been investigated by ICP/MS. The interference effects were not in the same direction. It appeared that concomitant elements such as Cl, S and C induce an enhancement effect, whereas N and P did not show any significant effect. And, Na and K caused a depression . We have found a link between the abundance of analytes and the ionization potential of concomitant elements (eV), except carbon and nitrogen