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Abstract  

Two compounds of antimony trichloride and bismuth trichloride with valine are synthesized by solid phase synthesis at room temperature. Their compositions, determined by element analysis, are Sb(C5H10O2N)3·2H2O and Bi(C5H10O2N)2Cl·0.5H2O. The crystal structure of antimony complex with valine belongs to triclinic system and its lattice parameters are: a=0.9599 nm, b=1.5068 nm, c=1.9851 nm, α=92.270, β=95.050, γ=104.270. The crystal structure of bismuth complex with valine belongs to monoclinic system and its lattice parameters are: a=1.6012 nm, b=1.8941 nm, c=1.839 nm, β=99.73°. The far-infrared spectra and infrared spectra show that the amino group and carboxyl of valine may be coordinated to antimony and bismuth, respectively, in two compounds. The TG-DSC results also reveal that the complexes were formed.

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Abstract  

The heat capacities (C p,m) of 2-amino-5-methylpyridine (AMP) were measured by a precision automated adiabatic calorimeter over the temperature range from 80 to 398 K. A solid-liquid phase transition was found in the range from 336 to 351 K with the peak heat capacity at 350.426 K. The melting temperature (T m), the molar enthalpy (Δfus H m 0), and the molar entropy (Δfus S m 0) of fusion were determined to be 350.431±0.018 K, 18.108 kJ mol−1 and 51.676 J K−1 mol−1, respectively. The mole fraction purity of the sample used was determined to be 0.99734 through the Van’t Hoff equation. The thermodynamic functions (H T-H 298.15 and S T-S 298.15) were calculated. The molar energy of combustion and the standard molar enthalpy of combustion were determined, ΔU c(C6H8N2,cr)= −3500.15±1.51 kJ mol−1 and Δc H m 0 (C6H8N2,cr)= −3502.64±1.51 kJ mol−1, by means of a precision oxygen-bomb combustion calorimeter at T=298.15 K. The standard molar enthalpy of formation of the crystalline compound was derived, Δr H m 0 (C6H8N2,cr)= −1.74±0.57 kJ mol−1.

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Abstract  

The thermal decomposition of Eu2(BA)6(bipy)2 (BA=C2H5N 2, benzoate; bipy=C10H8N2, 2,2'-bipyridine)and its kinetics were studied under the non-isothermal condition by TG-DTG, IR and SEM methods. The kinetic parameters were obtained from analysis of the TG-DTG curves by the Achar method, the Madhusudanan-Krishnan-Ninan (MKN) method, the Ozawa method and the Kissinger method. The most probable mechanism function was suggested by comparing the kinetic parameters. The kinetic equation for the first stage can be expressed as: dα/dt=Aexp(–E/RT)3(1–α)2/3.

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Abstract  

This paper reports the study of hydrogen and carbon monoxide produced by radiation degradation of N, N-dimethylhydroxylamine (DMHA). The results show that when the concentration of DMHA is between 0.1M–0.5M and the dose is between 10–1000 kGy, the volume fraction of hydrogen is very high and increases with the dose. The volume fraction of hydrogen is little dependent on the concentration of DMHA at lower dose but increases with increasing concentration of DMHA at higher dose. The volume fraction of carbon monoxide is very low.

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Abstract  

This paper reports on the qualitative and quantitative analyses of light hydrocarbons produced by radiation degradation of N,N-diethylhydroxylamine. The results show that when the absorbed doses are between 10 and 1000 kGy, the main light hydrocarbons are methane, ethane, ethene, propane and n-butane. Their volume fractions are increased with the increase of the dose. The volume fraction of ethene is also increased at low doses with the increase of the dose, but it is decreased with the increase of dose at high doses.

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Summary

The ripe fruits of Schisandrae chinensis have a long history of use in traditional Chinese medicine to treat diseases and improve health. There is substantial evidence that lignan constituents are mainly responsible for the beneficial effects of this plant medicine. The amounts of the major bioactive lignans in this plant vary widely with species, habitat, and the collecting time, and as such, establishment of an HPLC fingerprint for quality control of this herbal medicine is of particular importance. To achieve this, ten batches of Fructus schisandrae chinensis were collected from Tieli, in China, and their chemical components were analyzed under optimized HPLC conditions. On the basis of the chromatographic data, a consistent HPLC fingerprint pattern containing 20 common peaks was obtained. Among these common peaks, six were identified as schizandrin, schizandrol B, schisantherin, deoxyschiandrin, γ-schizandrin B, and schizandrin C. On the basis of this HPLC fingerprint and principal-components analysis, the quality of fifteen samples from different producing areas of China was objectively assessed, and the species difference between Fructus schisandrae sphenantherae and Fructus schisandrae chinensis was clearly differentiated. To summarize, the data described in this study offer valuable information for quality control and proper use of Fructus schisandrae chinensis.

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Abstract  

The complex of [Tb2(p-ClBA)6(PHEN)2] [(p-ClBA: p-chlorobenzoate and PHEN: 1,10-phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [Tb2(p-ClBA)6(PHEN)2] in dynamic nitrogen atmosphere was investigated by TG-DTG, SEM and IR techniques. By the kinetic method of processing thermal analysis data put forward by Malek et al., it is defined that the kinetic model for the first-step thermal decomposition is SB(m,n). The activation energy E and the pre-exponential factor lnA for this step reaction are 164 kJ mol-1 and 32.80, respectively. The lifetime equation at mass loss of 10% was deduced as lnτ=(-33.0569+20512.36/T by isothermal thermogravimetric analysis.

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Abstract  

N,N-dimethylhydroxylamine (DMHA) is a novel salt-free reducing reagent used in the separation U from Pu and Np in the reprocessing of power spent fuel. This paper reports on the radiolysis of aqueous DMHA solution and its radiolytic liquid organics. Results show that the main organics in irradiated DMHA solution are N-methyl hydroxylamine, formaldehyde and formic acid. The analysis of DMHA and N-methyl hydroxylamine were performed by gas chromatography, and that of formaldehyde was performed by ultraviolet–visible spectrophotometry. The analysis of formic acid was performed by ion chromatography. For 0.1–0.5 mol L−1 DMHA irradiated to 5–25 kGy, the residual DMHA concentration is (0.07–0.47) mol L−1, the degradation rate of DMHA at 25 kGy is 10.1–30.1%. The concentrations of N-methylhydroxylamine, formaldehyde and formic acid are (8.25–19.36) × 10−3, (4.20–36.36) × 10−3 and (1.35–10.9) × 10−4 mol L−1, respectively. The residual DMHA concentration decreases with the increasing dose. The concentrations of N-methylhydroxylamine and formaldehyde increase with the dose and initial DMHA concentration, and that of formic acid increases with the dose, but the relationship between the concentration of formic acid and initial DMHA concentration is not obvious.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
B. Zhang
,
S. D. Yao
,
K. Wang
,
D. B. Ding
,
Beijing 100871 P.R. China Beijing 100871 P.R. China
,
Beijing 100871 P.R. Beijing 100871 P.R. C
,
Beijing 100871 Beijing 100871
,
Beijing 1 Beijing 10
, and
Bei Beij

Summary  

Department of Technical Physics, School of Physics, Peking Unive

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