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  • Author or Editor: Juan Wang x
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The thermal decomposition process of the complex [Cu(NBOCTB)][Cu(NO3)4] H2O has been studied by TG and DTG technique, and possible intermediates of the thermal decomposition have also been conjectured from the TG and DTG curves. The results suggest that the decomposition of the complex involves five steps:

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A study of the synergistic extraction of uranium(VI) from sulphuric acid solution with 1-phenyl-3-methyl-4-(2-chlorobenzoyl)-pyrazolone-5 (PMCBP) together with di-(2-ethylhexyl)-phosphoric acid (HDEHP) and also mono-(2-ethylhexyl)-2-ethylhexyl-phosphate (HEHEHP) is described. The results suggest that the compositions of the extracted species is UO2XHA2 and UO2X2H2A2 respectively. Models for the extraction mechanism is also discussed.

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Au/SiO2 catalysts were prepared by self-assembly technique and characterized by EDS, XRD, XPS, AAS and N2 adsorption/desorption. They were found to be very efficient catalysts for the selective oxidation of cyclohexane with air in the absence of any solvent or promoter. The influences of Au loading, reaction temperature, reaction pressure and reaction time on the catalytic activity were explored in detail. Under suitable reaction conditions, the conversion of cyclohexane and total selectivity of cyclohexanone and cyclohexanol were up to ∼10 and ∼92%, respectively.

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The removal of heavy metal ion Co(II) from aqueous solution is studied using γ-Al2O3 by batch technique. The experiments are performed at T = 20 ± 2 °C, in 0.01 M NaNO3 solutions and under aerobic conditions. The effect of pH, ionic strength, fulvic acid (FA) and alumina concentration on the sorption of Co(II) on alumina are also respectively investigated. The pH affects the sorption of Co(II) significantly as compared with the effect of FA and ionic strength. The results indicate that strong chemical bonds are formed between Co(II) and the bare or FA coated alumina surface, and a transition from the adsorption to surface-induced precipitation of Co(II) on alumina surface takes place. The addition sequences of Co/FA on Co(II) sorption is also studied and the results indicate that the sorption of Co(II) in ternary system is independent of addition sequences. The results also suggest that the sorption of metal ions on mineral surface depends on the nature of mineral, nature of organic ligand and nature of metal ion.

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The thermal stability of sheepskin collagen cross-linked with chrome sulfate and mimosa (MI)–oxazolidine (OZ), respectively, had been researched in this experiment. All samples’ shrinkage temperatures (T s) are determined by a special T s-testing-apparatus and denaturation temperatures (T d) are determined by the differential scanning calorimetry. The relations between the modified collagens containing moisture and their hydrothermal stability, T s or T d, were studied. The results show that the cross linking agents can enhance the thermal stability of modified collagen whose T s are 109.8 and 110.6 °C for collagen treated with chrome and MI–OZ, respectively. When the samples contain 25–71.9% moisture for chrome leather and 20–71.1% for leather treated with MI–OZ, the hydrothermal stability will decrease with the increase of moisture. It was found that the difference between T s and T d of collagen modified by chrome is more obvious than that of collagen modified with MI–OZ. And when the moisture of chrome leather exceeds 55%, T d cannot express thermal stability of modified collagen as a substitute for T s, and the moisture is 40% for leather tanned with MI–OZ.

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A novel γ-MnO2 hollow structure has been synthesized using a simple chemical reaction between MnSO4 and KMnO4 in aqueous solution without using any templates, surfactants, catalysts, calcination and hydrothermal processes. As an example of potential applications, γ-MnO2 hollow structure was used as adsorbent in radionuclide 60Co(II) treatment, and showed an excellent ability. The effect of pH, contact time, ionic strength, humic acid (HA)/fulvic acid (FA), and temperature was investigated using batch techniques. The results indicated that the sorption of 60Co(II) on γ-MnO2 was obviously dependent on pH values but independent of ionic strength. The presence of HA/FA enhanced the sorption of 60Co(II) on γ-MnO2 at low pH, whereas reduced 60Co(II) sorption on γ-MnO2 at high pH. The kinetic sorption of 60Co(II) on γ-MnO2 can be well fitted by the pseudo-second-order rate equation. The thermodynamic parameters (ΔH 0, ΔS 0, ΔG 0) were also calculated from the temperature dependent sorption isotherms, and the results suggested that the sorption of 60Co(II) on γ-MnO2 was a spontaneous and endothermic process. The sorption of 60Co(II) on γ-MnO2 was attributed to surface complexation rather than ion exchange.

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An article assessment system based on both Tianjin University and nine key Chinese Universities’ academic disciplinary benchmarks was established to evaluate researcher’s published papers. With this scientific benchmarking system, the quality of a researcher’s papers could be easily located in a percentile scale in corresponding field within certain groups. Several factors, including total number of papers, order of authors, impact of journals, citation count, h-index, e-index, a-index, m-quotient, etc., were also utilized for both quantity and quality analysis. Furthermore, the novel proposed weighted citation analysis was introduced to judge a researcher’s contribution to his/her research outcomes. The convenient application and comprehensive evaluation property of this assessment system was thoroughly discussed via a given example.

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A novel hierarchically structured γ-MnO2 has been synthesized using a simple chemical reaction between MnSO4 and KMnO4 in aqueous solution without using any templates, surfactants, catalysts, calcination and hydrothermal processes. As an example of potential applications, hierarchically structured γ-MnO2 was used as adsorbent in radionuclide 63Ni(II) treatment, and showed an excellent ability. The effects of pH, ionic strength, temperature, humic acid (HA) and fulvic acid (FA) on the sorption of radionuclide 63Ni(II) to hierarchically structured γ-MnO2 have been investigated by using batch techniques. The results indicated that the sorption of 63Ni(II) on γ-MnO2 is obviously dependent on pH values but independent of ionic strength. The presence of HA/FA strongly enhances the sorption of 63Ni(II) on γ-MnO2 at low pH values, whereas reduces 63Ni(II) sorption at high pH values. The sorption of 63Ni(II) on γ-MnO2 is attributed to inner-sphere surface complexation rather than outer-sphere surface complexation or ion exchange. The thermodynamic parameters (ΔH 0, ΔS 0, ΔG 0) are also calculated from the temperature dependent sorption isotherms, and the results suggest that the sorption of 63Ni(II) on γ-MnO2 is a spontaneous and endothermic process.

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An antigastric cancer monoclonal antibody, 3H11 and its Fab fragment, were labeled with #-emitter 211At using p-[211At] astatobenzoic acid (PAtBA) intermediate. The astatinated antibodies had conspicuous cytotoxic effect on human gastric cancer cell M85 in vitro. Tissue distribution of the astatinated antibodies were investigated in nude mice with subcutaneous tumor xenografts by i.v. injection. The astatinated Fab fragment was better suitable for 7.2-hour half life of 211At, since its tumor uptake remained higher (9.48–8.42 I.D%/g) than the astatinated intact antibody (~4.0 I.D%/g) from 3 to 14-hour post injection. However, the undesired high 211At uptake of the astatinated antibodies in some normal tissues, such as stomach, kidney and lung, suggested that the 211At labeled antibodies should be further explored.

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A simple, rapid, and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed and validated for the simultaneous quantitation of PA-824 and moxifloxacin in rat plasma using carbamazepine as an internal standard (IS). The sample preparation involved a one-step protein precipitation method with methanol. The separation was performed on Inertsil® ODS3 C18 column (150 mm × 4.6 mm, 5 μm) and maintained at 30 °C. The mobile phase consisted of 0.1% formic acid in acetonitrile–water (90:10 v/v) with fast isocratic elution at a flow rate of 0.6 mL/min and a run time of 10 min. A mass spectrometer was run in the positive ion electrospray ionization (ESI) mode using multiple reaction monitoring (MRM) to monitor the mass transitions. The MRM transitions were chosen to be m/z 360.1 → m/z 175.0 for PA-824, m/z 402.0 → m/z 383.9 for moxifloxacin, and m/z 237.1 → m/z 194.0 for IS. The method was fully validated in terms of selectivity, linearity, accuracy, precision, matrix effect, recovery, and stability, respectively. The method was successfully applied to drug–drug interaction (DDI) study of PA-824 and moxifloxacin in rats. The results show that the main pharmacokinetic parameters of PA-824, namely, T max, t 1/2, and AUC(0–t), increased more in the PA-824 and moxifloxacin group than in the PA-824 group. However, there were little changes in the main pharmacokinetic parameters of moxifloxacin from single and combined groups.

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