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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1421-1428页

作者： GAO Xianhui WU Jinjin ZHAO lianquan analytical and testing Center Huazhong University of Science and TechnologyWuhan 430074China

The grain refinement mechanism and texture evolution of electromagnetically formed polycrystalline Cu sheets were investigated using the electron back-scattered diffraction(EBSD) technique. It is found that the average grain size decreases from 35.88 μm to 8.77 μm. The grain refinement was mainly attributed to dynamic recrystallization(DRX) at the grain boundary regions of bulged Cu samples where the inhomogeneous dislocation density and the large lattice misorientation were observed. The DRX mechanisms at the grain boundaries were discussed with respect to the strain-induced grain boundary migration nucleation. Moreover, the orientation distribution function(ODF) of the sample with the strain of 50% demonstrated a strong {110} texture and a relatively weak {001} texture. The texture evolution was discussed using the plastic work values of the grains with various orientations, which were calculated according to the Taylor model and the virtual work principle. The experimental results show that the expended plastic work of the grains with {110} orientation is 9.69 MPa, which is distinctly higher than those of the grains with the {001} and {111} orientations. This indicates that the formation of the {110} orientated texture would be preferred with increasing strain in good agreement with the experimental result.

关键词： grain refinement texture electrom agnetic forming electron back-scattered diffraction

Study on the inclusion interaction of methylated-β-cyclodextrins with albendazole by spectrofluorimetry and its application

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Chinese Chemical Letters 2008年第8期19卷 951-954页

作者： Guo Yan Zhao Hao Wu Sheng Li Dong Li Ming Du analytical and testing Center Shanxi Normal University Linfen 041004 China

The inclusion interaction between three types of methylated-β-cyclodextrins （Me-β-CDs） and albendazole （ABZ） was studied by spectrofluorimetry. The result showed that Me-β-CDs reacted with ABZ to form an inclusion complex, 1： 1 stoichiometry for Me- β-CDs-ABZ complex was established and its association constant have been determined from fluorescence data by Benesi- Hildebrand＇s method （double reciprocal plots）. It was noted that 2,6-DM-β-CD exhibited stronger binding ability than other Me-β- CDs. Based on the significant enhancement of fluorescence intensity of inclusion complex, a simple and highly sensitive fluorimetric method is proposed for the determination of ABZ in the presence of 2,6-DM-β-CD. The proposed method was successfully applied to the determination of ABZ in tablets and human urine.

关键词： Methylated-β-cyclodextrins Albendazole Spectrofluorimetry

A Janus heteroatom-doped carbon electrocatalyst for hydrazine oxidation

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National Science Review 2023年第3期10卷 152-162页

作者： Jieting Ding Hao-Fan Wang Xianfeng Yang Wenbo Ju Kui Shen Liyu Chen Yingwei Li School of Chemistry and Chemical Engineering South China University of Technology analytical and testing centre South China University of Technology School of Physics and Optoelectronics South China University of Technology

The trade-off between the intrinsic activity and electronic conductivity of carbon materials is a major barrier for *** report a Janus-type carbon material combining electrically conductive nitrogen-doped carbon(NC) and catalytically active boron,nitrogen co-doped carbon(BNC).The integration of NC with BNC can not only ensure high electronic conductivity of the hybrid,but also achieve an enhancement in the intrinsic activity of the BNC side due to the electron redistribution on their coupling *** the electro catalytic hydrazine oxidation reaction(HzOR),the Janus carbon electrocatalyst exhibits superior activity than their single counterparts and simple physical mixtures.D ensity functional theory calculations reve al that the NC/BNC interfaces simultaneously promote efficient electron transport and decrease the free energy of the rate-determining step in the HzOR process.

关键词： electronic conductivity heteroatom-doped carbon hydrazine oxidation reaction intrinsic activity metal–organic frameworks

Use of Sewage Sludge After Liming as Fertilizer for Maize Growth

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Pedosphere 2008年第2期18卷 203-213页

作者： M.K.JAMALI T.G.KAZI M.B.ARAIN H.I.AFRIDI A.R.MEMON N.JALBANI A.SHAH National centre of Excellence in analytical Chemistry

The use of sewage sludge on agricultural land provides an alternative for its disposal. Therefore, the aim of the present study was to evaluate the feasibility of using industrial sewage sludge produced in Pakistan, as an agricultural fertilizer. The agricultural soil amended with 250 g kg^-1 sewage sludge with or without lime treatment was used for the growth of the common local grain crop, maize （Zea maize）. The mobility of the trace and toxic metals in the sludge samples was assessed by applying a modified BCR sequential extraction procedure. The single extraction procedure was comprised of the application of a mild extractant （CaCl2） and water, for the estimation of the proportion of easily soluble metal fractions. To check the precision of the analytical results, the concentrations of trace and toxic metals in every step of the sequential extraction procedure were summed up and compared with total metal concentrations. The plant-available metal contents, as indicated by the deionized water and 0.01 mol L^-1 CaCl2 solution extraction fractions and the exchangeable fraction of the sequential extraction, decreased significantly （P 〈 0.05） with lime application because of the reduced metal availability at a higher pH, except in the cases of Cd and Cu, whose mobility was slightly increased. Sludge amendment enhanced the dry weight yield of maize and the increase was more obvious for the soil with lime treatment. Liming the sewage sludge reduced the trace and toxic metal contents in the grain tissues, except Cu and Cd, which were below the permissible limits of these metals. The present experiment demonstrates that liming was an important factor in facilitating the growth of maize in sludge-amended soil.

关键词： lime treatment maize metals sequential extraction sewage sludge

Ion behavior and interelectrode breakdown voltage of a drift tube

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Chinese Physics C 2015年第5期39卷 98-104页

作者：耿浩赵忠俊段忆翔 Research Center of analytical Instrumentation Analytical & Testing Center Sichuan University Research Center of analytical Instrumentation College of Chemistry Sichuan University Research Center of analytical Instrumentation College of Life Science Sichuan University

We experimentally studied ion behavior and interelectrode breakdown voltage. The ion behavior of a drift tube directly influences the detection of ion intensity, and then influences the detection sensitivity of a system. Interelectrode voltage and pressure directly influence the ion behavior. Gas discharge between electrodes influences the adjustments required for interelectrode voltage. The experimental results show： ion intensity increases exponentially with the increment of voltage between drift electrodes; ion intensity decreases exponentially as pressure increases; with the increment of pressure, the breakdown voltage at first decreases, and then increases; ion injection has a significant influence on breakdown voltage, and this influence depends on the pressure and shapes of the electrodes. We explain the results above through assumptions and by mathematical methods.

关键词： drift tube breakdown voltage ion behavior

SYNTHESIS AND CHARACTERIZATION OF POLY(p-ARYLENE SULFIDE KETONE/SCHIFF BASE) COPOLYMERS

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Chinese Journal of Polymer Science 2012年第3期30卷 370-377页

作者：杨杰 analytical and testing Center Sichuan University State Key Laboratory of Polymer Materials & Engineering(Sichuan University)

Poly（p-arylene sulfide ketone/Schiffbase） copolymers （PASK/SB） were prepared by solution polycondensation of 4,4＇-diflurobenzophenone （DFBP） and N-phenyl（4,4＇-diflurodiphenyl） ketimine （DFBI） with sodium sulfide in the presence of sodium hydroxide under normal pressure. Elemental analyses, FT-IR, NMR, DSC, TGA and XRD were used to characterize the resultant copolymers. It was found that the copolymers had good thermal properties with glass transition temperature （Tg） of 155.0-172.0℃, melting temperature （Tm） of 298-344℃, 5% weight loss temperatures （Td） of 471.0-501.5℃. These copolymers were almost amorphous with the content of DFBI beyond 30%. The polymer with 100% DFBI had excellent solubility, and it could dissolve in some solvents such as tetrahydrofuran （THF） and N-methyl-2- pyrrolidone （NMP）. The processability of polymers was improved. Meantime the viscosity of PASK made from hydrolysis of PASK/SB （H-PASK/SB） was greatly improved from 0.135 dL/g to 0.605 dL/g.

关键词： Synthesis PASK Schiffbase Copolymer Spin ability.

Construction and Properties of Simvastatin and Calcium Phosphate Dual-Loaded Coaxial Fibrous Membranes with Osteogenic and Angiogenic Functions

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Journal of Bionic Engineering 2022年第6期19卷 1645-1657页

作者： Chang Liu Dan Deng Jing Gao Shue Jin Yi Zuo Yubao Li Jidong Li Research Center for Nano-Biomaterials Analytical&Testing CenterSichuan UniversityChengdu610064China

The ideal Guided Bone Regeneration(GBR)membrane is required to have good biocompatibility,space maintenance ability,appropriate degradation rate,and preferably can guide the regeneration of vascularized bone *** this study,Simvastatin(SIM)and calcium Phosphate(CaP)were encapsulated in a Polycaprolactone(PCL)/Chitosan(CS)core-shell structural fibrous membranes via coaxial electrospinning *** results showed that loaded SIM in the core of the core-shell structure fibrous membranes could sustainably release the drug for more than two months and upregulate the angiogenic marker of Bone Mesenchymal Stem Cells(BMSCs).Adding a certain amount of CaP to the shell layer provided more sites for the mineralization and synergistic with SIM to promote osteogenic differentiation of BMSCs in *** intramuscular implantation experiments in rabbits suggested a normal early inflammation and enhanced vascularization induced by the SIM-loaded fibrous *** study proposed an effective strategy to prepare a dual-loaded core-shell fibrous membrane for guided vascularized bone tissue regeneration.

关键词： Simvastatin Calcium phosphate Coaxial electrospinning Vascularization Guided Bone Regeneration

NMR analysis of a pair of isomers

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Chinese Chemical Letters 2012年第10期23卷 1181-1184页

作者： Jing Li Zhu Feng Geng Peng Liu Zhi Wei Deng analytical&testing Center Beijing Normal UniversityBeijing 100875China

In this work, the structures of a pair of isomers were identified. And we showed the ability of the selective 1D version, performed the most common NMR experiments including the 1D-HMBC and GOESY experiments, to determine the isom^ric composition that were found in the production process of roflumilast. The experimental results proved that this method would be even more time saving and could get more reliable results.

关键词： Isomer identification 1D-selective NMR experiments qNMR

Study on the inclusion interactions of berberine hydrochloride and cucurbit[7] by spectrofluorimetry

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Chinese Chemical Letters 2009年第3期20卷 322-325页

作者： Yan Ping Li Hao Wu Li Ming Du analytical and testing Center Shanxi Normal University Linfen 041004 PR China

The inclusion interaction between berberine hydrochloride （BRH） and cucurbit[7] （CB[7]） has been studied by spectrofluorimetry. The result showed that CB[7] interaction with BRH to form a stable inclusion complex with an association constant of 9.57 × 10^4 L/mol and the fluorescence intensity of the complex was enhanced in 17 times higher than that of the studied drug itself. Based on the significant enhancement of fluorescence intensity of BRH in inclusion complex, a spetrofluorimetric method with high sensitivity and selectivity was developed for the determination of BRH in aqueous solution. The linear range of the method was 3.2- 2 × 10^3 ng/mL with a detection limit of 1.1 ng/mL. The proposed procedure could be applied successfully to determination of BRH remained in pharmaceutical dosage forms, spiked human plasma and urine with satisfactory results.

关键词： Berberinc hydrochloride Cucurbit Spectrofluorimetry Inclusion interaction

Exploration of nano-surface chemistry for spectral analysis

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Chinese Science Bulletin 2013年第18期58卷 2017-2026页

作者： LI ChengHui LIU Rui Lü Yi HOU XianDeng WU Peng College of Chemistry Sichuan University analytical & testing Center Sichuan University

The applications of nano-surface chemistry in the field of spectral analysis have attracted growing interest in recent *** this article,we reviewed the applications of nanomaterials-based chemical reactions for spectral analysis,including the development in plasma-catalysis,surface-enhanced spectroscopy,separation and preconcentration,chemical vapor generation,labeling and signal *** of nano-surface chemistry to spectral analysis not only improves the sensitivity and selectivity,broadens the application range of spectral analysis,but also affords analytical community special characterization tools.

关键词：纳米材料光谱分析表面化学频谱分析等离子体催化化学领域化学反应表面增强