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Recrystallized microstructural evolution of UFG copper prepared by asymmetrical accumulative rolling-bonding process

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Transactions of Nonferrous Metals Society of China 2010年第4期20卷 559-563页

作者：王军丽史庆南钱天才王绍华杨喜昆 Research Center for Analysis and Measurement Kunming University of Science and Technology

Copper sheet with grain size of 30-60μm was processed by plastic deformation of asymmetrical accumulative rolling-bonding(AARB)with the strain of 3.2.The effects of annealing temperature and time on microstructural evolution were studied by means of electron backscattered diffraction(EBSD).EBSD grain mapping,recrystallization pole figure and grain boundary misorientation angle distribution graph were constructed,and the characteristics were assessed by microstructure,grain size,grain boundary misorientation and texture.The results show that ultra fine grains(UFG)are obtained after annealing at 250℃ for 30?40 min.When the annealing is controlled at 250℃for 40 min,the recrystallization is finished,a large number of small grains appear and most grain boundaries consist of low-angle boundaries.The character of texture is rolling texture after the recrystallization treatment,but the strength of the texture is faint.While second recrystallization happens,{110}+{112} texture component disappears and turns into{122}cube twin texture component.

关键词： severe deformation asymmetrical accumulative rolling-bonding ultra fine grains copper

Pyrolysis of Polytrimethylene Terephthalate(PTT) Fiber by Pyrolysis Gas Chromatography-Mass Spectroscopy

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Journal of Donghua University(English Edition) 2007年第5期24卷 604-609页

作者：钱和生 Research Center for Analysis and Measurement Donghua University

Pyrolysis of polytrimethylene terephthalate(PTT) fiber has been investigated by pyrolysis gas chromatography-mass spectroscopy in the temperature range from 400℃ to 750℃ in order to observe the possible effect of the temperature on its composition of pyrolysates.At 400℃,pyrolysis of molecular chain could occur,only 13 pyrolysates could be identified.The trimethylene moieties bound to the macromolecular core by ester bonds are cleaved at around 400℃.At 550℃-750℃,pyrolysis of molecular chain could completely take place,46 pyrolysates could be found.As the temperature increases,the compositions of pyrolysate are distinctly increased.Several compounds,especially benzoic acid,monopropenyl-p-phthalate,2-propenyl benzoate,di-2-propenyl ester,1,4-benzenedicarboxylic acid,benzene,1,5-hexadiene,biphenyl and 1,3-propanediol dibenzoate could be formed.The thermal degradation mechanism,which is determined by structure and amount of the thermal decomposition products,are described.During pyrolysis of polytrimethylene terephthalate,polymeric chain scissions take place a peeling reaction as a successive removal of the dimer units from the polymeric chain.The chain scissions are followed by the elimination reaction,linkage action and secondary reactions,which bring about a variety fragment.

关键词：聚环丙烷对苯二酸酯高温分解热降解气相色谱-质谱法

Seasonal variations and size distributions of water-soluble ions in atmospheric aerosols in Beijing, 2012

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Journal of Environmental Sciences 2015年第8期27卷 197-205页

作者： Yongjie Yang Rui Zhou Jianjun Wu Yue Yu Zhiqiang Ma Lejian Zhang Yi'an Di National research center for Environmental analysis and measurement Jiangsu Institute of Meteorological Sciences Beijing Urban Meteorological Engineering Technology research center Meteorological Observation center China Meteorological Administration

The characteristics of water-soluble ions in airborne particulate matter in Beijing were investigated using ion chromatography. The results showed that the total concentrations of ions were 83.7 ± 48.9 μg/m3 in spring, 54.0 ± 17.0 μg/m3 in summer, 54.1 ± 42.9 μg/m3 in autumn, and 88.8 ± 47.7 μg/m3 in winter, respectively. Furthermore, out of all the ions, NO3-,SO42-and NH4＋accounted for 81.2% in spring, 78.5% in summer, 74.6% in autumn, and 76.3%in winter. Mg2＋and Ca2＋were mainly associated with coarse particles, with a peak that ranged from 5.8 to 9.0 μm. Na＋, NH4＋and Cl-had a multi-mode distribution with peaks that ranged from 0.43 to 1.1 μm and 4.7 to 9.0 μm. K＋, NO3-, and SO42-were mainly associated with fine particles, with a peak that ranged from 0.65 to 2.1 μm. The concentrations of Na＋, K＋,Mg2＋, Ca2＋, NH4＋, Cl-, NO3-and SO42-were 2.69, 2.32, 1.01, 4.84, 16.9, 11.8, 42.0, and 44.1 μg/m3 in particulate matter（PM） on foggy days, respectively, which were 1.4 to 7.3 times higher than those on clear days. The concentrations of these ions were 2.40, 1.66, 0.92, 4.95, 17.5,7.00, 32.6, and 34.7 μg/m3 in PM on hazy days, respectively, which were 1.2–5.7 times higher than those on clear days.

关键词： Water-soluble ions Size distribution Hazy day Foggy day Beijing

analysis of Pyrolysates for Polysulphoneamide Fiber by Py-GC/MS

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Journal of Donghua University(English Edition) 2006年第2期23卷 63-67页

作者：钱和生林丹丽 Research Center for Analysis and Measurement Donghua University

Pyrolysis of polysulphoneamide fiber has been investigated using pyrolysis gas chromatography-mass spectroscopy at the different temperatures from 420℃ to 750℃. Its com-positions of pyrolysates have been analyzed. At 420 ℃, pyrolysis of molecular chain could not completely take place, 12 compounds of pyrolysis have only been identified. When the temperature increases, the compositions of pyrolysate increase sharply. Several compounds, especially sulfur dioxide, benzene, aniline, benzoic acid, 1,4-benzene dicaronitrile, N-phenyl-acetamide, diphenylamine, benzo[g] isoquinoline, N-phenyl-benzamide, N-(4-cyanophenyl) benzamide, could be formed.The degradation mechanisms which are determined by structure and amount of the thermal decomposition products are described. During pyrolysis, for polysulphoneamide, polymeric chain scissions take place as a successive removal of the monomer units from the polymeric chain. The chain scissions are followed by secondary reactions, which lead to a variety of compounds. Additional reactions can also take place during pyrolysis.

关键词：热解气体色谱法质量光谱学分子链

Rapid and sensitive analysis of trace b-blockers by magnetic solidphase extraction coupled with Fourier transform ion cyclotron resonance mass spectrometry

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Journal of Pharmaceutical analysis 2022年第2期12卷 293-300页

作者： Xue Xiao Kaili He Ya-Jun Hou Zhangmin Xiang Yunyun Yang Guangdong Provincial Key Laboratory of Chemical measurement and Emergency Test Technology Guangdong Provincial Engineering Research Center for Ambient Mass SpectrometryInstitute of AnalysisGuangdong Academy of Sciences(China National Analytical CenterGuangzhou)Guangzhou510070China

A rapid and sensitive method for analyzing trace b-blockers in complex biological samples,which involved magnetic solid-phase extraction(MSPE)coupled with Fourier transform ion cyclotron resonance mass spectrometry(FTICR-MS),was developed.Novel nanosilver-functionalized magnetic nanoparticles with an interlayer of poly(3,4-dihydroxyphenylalanine)(polyDOPA@Ag-MNPs)were synthesized and used as MSPE adsorbents to extract trace b-blockers from biological samples.After extraction,the analytes loaded on the polyDOPA@Ag-MNPs were desorbed using an organic solvent and analyzed by FTICR-MS.The method was rapid and sensitive,with a total detection procedure of less than 10 min as well as limits of detection and quantification in the ranges of 3.5-6.8 pg/mL and 11.7-22.8 pg/mL,respectively.The accuracy of the method was also desirable,with recoveries ranging from 80.9%to 91.0%following the detection of analytes in human blood samples.All the experimental results demonstrated that the developed MSPE-FTICR-MS method was suitable for the rapid and sensitive analysis of trace b-blockers in complex biological samples.

关键词： β-blockers Magnetic solid-phase extraction Nanosilver-functionalized magnetic nanoparticles Poly(3,4-dihydroxyphenylalanine) Fourier transform ion cyclotron resonance mass spectrometry

Electrochemical energy storage application of CuO/CuO@Ni-CoMoO4·0.75H2O nanobelt arrays grown directly on Cu foam

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Progress in Natural Science:Materials International 2022年第2期32卷 163-170页

作者： Bingbing Zhang Qian Liu Kaibing Xu Rujia Zou Chunrui Wang Department of Physics Donghua University Research Center for Analysis and Measurement Donghua University State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University

Supercapacitors are attracting huge research interest because they are expected to achieve battery-level energy density,and they have a longer calendar life and shorter charging time.However,due to the out shell materials without contact extra freeway for charge transports,the out shell materials have still limited contribution to high capacitance for array structure at high rates.Here,CO/CO@Ni-CMO NBs were designed and synthesized on Cu foam substrates with CuO NBs as cores or extra freeway and Ni-CoMoO4·0.75 H2O nanobelt as shell by an easily synthetic method.CuO NBs will provide electron "superhighways" and extra outside freeway for charge storage and delivery.Besides,the Ni doped CoMoO4·0.75 H2O NBs are conducive to the electrical conductivity,and open space among these nanosheets can act as an "ion reservoir",the increment of active sites and the contribution of capacitive effects.Finally,the CO@Ni-CMO NBs directly grown on Cu foam could avoid the "dead" volume caused by the tedious process of mixing active materials with polymer binders/conductive additives.As expected,the CO/CO@Ni-CMO NBs exhibited the high specific capacitance,the good rate performance and the excellent electrochemical stability.

关键词： CuO/ [email protected] –CoMoO 4 ·0.75H 2 O Nanobelt arrays Multipath transfer electrons High specific capacitance Cyclic stability

Detection of composition of functional component theabrownins in Pu-erh tea by degradation method

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Food Science and Human Wellness 2022年第3期11卷 643-647页

作者： Simin Hu Xiaolei Li Chuangchuang Gao Xianyu Meng Mingchao Li Yuqian Li Tianrui Xu Qian Hao Faculty of Life Science and Technology Kunming University of Science and TechnologyKunming 650500China Research Center for Analysis and Measurement Kunming University of Science and TechnologyKunming 650093China

Habitual tea consumption can reduce the risk of ASCVD morbidity and mortality and all-cause mortality in China,and long-term adherence to this habit can provide greater protection.Pu-erh tea is one of the representatives of post-fermented teas,and the polymers in Pu-erh tea have anti-cancer and anti-hyperlipidemic activities,but their chemical composition is still unknown.In this study,the chemical composition of Pu-erh tea was investigated in detail and eight(1–8)known compounds were isolated.The polymers in Pu-erh tea were also degraded by thiol degradation,and the fragments of quercetin and(–)-epicatechin-3-O-gallate were found in the thiol degradation products of Pu-erh tea polymers by UPLC observation and separation and purification.This is the first time that this fragment was obtained in Pu-erh tea polymer.

关键词： Pu-erh tea Polymer Theabrownin Thiol degradation

Self-assembly of Hollow PNIPAM Microgels to Form Discontinuously Hollow Fibers

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Chinese Journal of Polymer Science 2014年第11期32卷 1544-1549页

作者： Xiao-yun Liu Jian-mao Yang 查刘生 Zi-jun Jiang Research Center for Analysis and Measurement Donghua University State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University

A new kind of hollow hydrogel microfiber with discontinuous hollow structure was prepared by an ice-segregation-induced self-assembly process. Monodisperse thermo-responsive hollow poly（N-isopropylacrylamide）（PNIPAM） microgels were first synthesized by seed precipitation polymerization using colloidal Si O2 nanoparticles as seeds, followed by removing the silica cores of the formed Si O2/PNIPAM core/shell composite microgels with hydrofluoric acid. Then, the discontinuously hollow hydrogel microfibers were produced by unidirectional freezing of 1 wt% hollow PNIPAM microgel aqueous dispersion in liquid nitrogen bath, followed by freeze-drying to remove the formed ice crystals. Many orderly arrayed dents were observed on the surfaces of the hydrogel microfibers by field-emission scanning electron microscopy, indicating that they are constructed by closely packed monodisperse hollow PNIPAM microgels. The effect of freezing method and the hollow microgel concentration in the aqueous dispersion on the morphological structure of the hollow hydrogel microfibers was investigated.

关键词： Discontinuously hollow microfiber Ice-segregation-induced self-assembly Thermo-responsiveness N-isopropylacrylamide Microgel.

Concentration and source identification of polycyclic aromatic hydrocarbons and phthalic acid esters in the surface water of the Yangtze River Delta,China

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Journal of Environmental Sciences 2012年第2期24卷 335-342页

作者： Lifei Zhang Liang Dong Lijun Ren Shuangxin Shi Li Zhou Ting Zhang Yeru Huang State Environmental Protection Key Laboratory of Dioxin Pollution Control National Research Center for Environmental Analysis and Measurement Beijing 100029 China

The pollution from polycyclic aromatic hydrocarbons（PAHs） and phthalic acid esters（PAEs） in the surface water of the rapidly urbanized Yangtze River Delta region was investigated.Fourteen surface water samples were collected in June 2010.Water samples were liquid-liquid extracted using methylene chloride and analyzed by gas chromatography-mass spectrometry.Concentrations of PAHs and PAEs ranged 12.9-638.1 ng/L and 61-28550 ng/L,respectively.Fluoranthene,naphthalene,pyrene,phenanthrene,di-2ethylhexyl phthalate,and di-n-butyl phthalate were the most abundant compounds in the samples.The water samples were moderately polluted with benzo[a]pyrene according to China＇s environmental quality standard for surface water.The two highest concentrations of PAHs and PAEs occurred in samples from Taihu Lake,Wuxi City and the western section of Yangchenghu Lake.Potential sources of pollution at S7 were petroleum combustion and the plastics industry,and at Yangchenghu Lake were petroleum combustion and domestic waste.Pollution in samples from the Beijing-Hangzhou Grand Canal originated from diesel engines.There were no obvious sources of pollution for the other water samples.These results can be used as reference levels for future monitoring programs of pollution from PAHs and PAEs.

关键词： polycyclic aromatic hydrocarbons phthalic acid esters Yangtze River Delta surface water