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  • Author or Editor: Jing Yang x
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Abstract

This study discusses the thermal behavior of the 6.5 Ah cylinder Ni/MH hydride battery with 0.5 wt% ytterbium oxide (Yb2O3) in nickel electrode and 1.0 wt% super absorbent polymer (SAP) in hydrogen-storage alloy (MH) electrode during charging to 150% of its rating capacity. Quantity of heat and heat generation rate of the battery during charging are studied by quartz frequency microcalorimeter. Heat generation curve is fitted into a function, and heat transport equation is solved. Using measured data, the internal temperature profiles at the terminal moment of charging at 1C, 3C, and 5C are simulated by FEM. Influence of Yb2O3 and SAP on the thermal behavior of Ni/MH battery is examined by the two-dimensional thermal model. Results show that addition of Yb2O3 and SAP can achieve substantial improvement for thermal behavior of Ni/MH battery at 1C,3C, and 5C charging.

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Abstract  

The transition of cubic indium hydroxide to cubic indium oxide has been studied by thermogravimetric analysis complimented with hot-stage Raman spectroscopy. Thermal analysis shows the transition of In(OH)3 to In2O3 occurs at 219 °C. The structure and morphology of In(OH)3 synthesised using a soft chemical route at low temperatures was confirmed by X-ray diffraction and scanning electron microscopy. A topotactical relationship exists between the micro/nano-cubes of In(OH)3 and In2O3. The Raman spectrum of In(OH)3 is characterised by an intense sharp band at 309 cm−1 attributed to ν1 In–O symmetric stretching mode, bands at 1137 and 1155 cm−1 attributed to In-OH δ deformation modes, bands at 3083, 3215, 3123 and 3262 cm−1 assigned to the OH stretching vibrations. Upon thermal treatment of In(OH)3, new Raman bands are observed at 125, 295, 488 and 615 cm−1 attributed to In2O3. Changes in the structure of In(OH)3 with thermal treatment is readily followed by hot-stage Raman spectroscopy.

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Abstract  

This work reports the synthesis, radiolabeling and preliminary biodistribution results in tumor-bearing mice of the 99mTc(CO)3–AOPA colchicine conjugate. The novel ligand was successfully synthesized by conjugation of N-(acetyloxy)-2-picolylamino (AOPA) to deacetylcolchicine via a short carbonyl-methylene linker. Radiolabeling was performed in high yield with [99mTc(CO)3]+ core. 99mTc(CO)3–AOPA colchicine conjugate was hydrophilic and was stable at room temperature. Biodistribution studies in tumor-bearing mice showed that 99mTc(CO)3–AOPA colchicine conjugate accumulated in the tumor with good uptake and retention. However, its clearance from normal organs was not so fast, resulting in poor T/NT ratios. Further modification on the linker or/and 99mTc-chelate to improve the tumor targeting efficacy and in vivo kinetic profiles is currently in progress.

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Abstract

Ternary nanostructured CuO/Ti0.8Ce0.2O2 catalysts were prepared by a one-step surfactant-assisted method of nanoparticle assembly. The textural and structural properties of the CuO/Ti0.8Ce0.2O2 catalysts were characterized by XRD, TGA, BET, XPS and H2-TPR. Their catalytic performance for low-temperature CO oxidation was studied by using a catlab system. CuO supported on binary Ti0.8Ce0.2O2 support showed higher catalytic activity than CuO supported on single CeO2 or TiO2 support. The calcination temperature had a remarkable influence on the catalytic activity of the CuO/Ti0.8Ce0.2O2 catalysts. The CuO/Ti0.8Ce0.2O2 catalyst calcined at 500 °C exhibited the highest catalytic activity with T50% and T100% at 82 and 123 °C, respectively. According to the XRD, BET and H2-TPR analyses, the higher surface areas and more highly dispersed small particle size CuO should be responsible for the high catalytic activity of catalysts.

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A double-development TLC method has been developed for simultaneous qualitative and quantitative analysis of hydrophilic and lipophilic constituents of Salvia miltiorrhiza (Danshen). The optimized mobile phases dichloromethane-ethyl acetate-formic acid 22:24:10 (ν/ν) and petroleum ether-ethyl acetate-cyclohexane 25:11:14 (ν/ν) were used for the double development on nano-silica gel 60F254 plates. Their characteristic TLC profiles were observed under UV light at 254 and 365 nm and the bands were then revealed by reaction with 5% H2SO4 in EtOH. Quantification of twelve compounds was achieved by densitometry at 260 or 290 nm, with reference at 400 nm. Linearity was quite good (R2 > 0.99) within the ranges tested. This method could be used for quality control of Danshen.

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Haiying Wang, Yucheng Yang, Jianhong Wei, Ling Le, Yang Liu, Chunxu Pan, Pengfei Fang, Rui Xiong, and Jing Shi

Abstract

Nitrogen-doped titanium dioxide (TiO2) nanotube arrays were synthesized by anodization in ethylene glycol electrolyte and annealing in ammonia at 500 °C. Detailed analysis showed that the nitrogen-doped titania nanotubes were pure anatase of ordered structure, with a crystallite size of 8.5 nm. The doping nitrogen atoms were induced on the interstitial sites and substitutional sites and the ratio of oxygen vacancies increased to 27.15 %, resulting in an add-on peak in the absorption spectrum and extended the absorption from 387 to 618 nm. The photocatalytic activity of the nitrogen-doped TiO2 nanotubes was evaluated by photocatalytic degradation of methyl blue under visible light irradiation. Significant improvement of photocatalytic activity under visible light irradiation was observed. We assumed the nitrogen doping induced the effect produced by nitrogen atoms, Ti3+ cations and oxygen vacancies and the size effect of the TiO2 crystallite should be responsible for the effective photocatalytic activity.

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Abstract

The thermal behavior and decomposition of kaolinite–potassium acetate intercalation complex was investigated through a combination of thermogravimetric analysis and infrared emission spectroscopy. Three main changes were observed at 48, 280, 323, and 460 °C which were attributed to (a) the loss of adsorbed water, (b) loss of the water coordinated to acetate ion in the layer of kaolinite, (c) loss of potassium acetate in the complex, and (d) water through dehydroxylation. It is proposed that the potassium acetate intercalation complex is stability except heating at above 300 °C. The infrared emission spectra clearly show the decomposition and dehydroxylation of the kaolinite intercalation complex when the temperature is raised. The dehydration of the intercalation complex is followed by the loss of intensity of the stretching vibration bands at region 3600–3200 cm−1. Dehydroxylation is followed by the decrease in intensity in the bands between 3695 and 3620 cm−1. Dehydration is completed by 400 °C and partial dehydroxylation by 650 °C. The inner hydroxyl group remained until around 700 °C.

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Abstract  

This work reports the synthesis, radiolabeling and preliminary biodistribution results in tumor-bearing mice of [99mTc(CO)3(IDA–PEG3–CB)]. The novel chlorambucil derivative was successfully synthesized by conjugation of iminodiacetic acid (IDA) to chlorambucil via a pegylated linker. The ligand could be labeled by [99mTc(CO)3]+ core in high yield to get [99mTc(CO)3(IDA–PEG3–CB)], which was very hydrophilic and was stable at room temperature. Biodistribution studies in tumor-bearing mice showed that [99mTc(CO)3(IDA–PEG3–CB)] accumulated in the tumor with favorable uptake and retention. The good accumulation in tumor tissue with high tumor/muscle ratios warrants further research to improve tumor targeting efficacy and pharmacokinetic profile of radiolabeled chlorambucil derivative by structural modification.

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10-Methoxycamptothecin (MCPT) and 10-hydroxycamptothecin (HCPT) are the indole alkaloids isolated from a Chinese tree, Camptotheca acuminata, and have a wide spectrum of anticancer activity in vitro and in vivo mainly through inhibitory effects on topoisomerase I. HCPT is a major metabolite of MCPT in rats; the pharmacokinetic analysis and tissue distribution of MCPT and HCPT in rats have also been determined after i.v. injection of MCPT, but the excretion of MCPT and its metabolite HCPT has not been assessed up to now. In the present study, the excretion study of MCPT and its metabolite HCPT in rat bile, feces, and urine after i.v. administration of MCPT (5 mg kg−1) was performed by high-performance liquid chromatography (HPLC) method coupled with a fluorescence detector. The results showed that MCPT mainly biotransformed to HCPT and excreted in the form of HCPT and MCPT in bile, urine, and feces after i.v. administration of MCPT. It was excreted about 1.24 ± 0.07% as MCPT and 5.49 ± 0.40% as HCPT in bile within 6 h after i.v. administration. The cumulative excretions of MCPT and HCPT were mainly within 24 h after i.v. administration, which were 0.41 ± 0.10% and 7.66 ± 1.43% of the dosage in urine and about 0.16 ± 0.04% and 20.30 ± 3.35% of the dosage in feces. The total excretion of MCPT in urine, bile, and feces was 1.81 ± 0.09% in the form of original MCPT and 33.45 ± 1.57% detected as the metabolite HCPT in urine, bile, and feces, suggesting that MCPT might undergo other biotransformation.

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