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Chemical Research in Chinese Universities 2007年第5期23卷 579-584页

作者： LIU Xiu-dong yu wei-ting LIN Jun-zhang MA Xiao-jun yuAN Quan Laboratory of Biomedical Material Engineering Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P. R. China College of Environment and Chemical Engineering Dalian University Dalian 116622 P. R. China

Alginate has been widely used in cell microencapsulation and drug delivery systems in the form of gel beads or *** an alternative novel emulsification-internal gelation technology has been established and both the properties and the potential applications of the beads in drug delivery systems have been studied,the mechanism has not been well understood compared with the traditional droplet method（external gelation technology）.On the basis of our previous knowledge that the novel technology is composed of complicatedly consecutive processes with multistep diffusion and reaction,and the diffusion of acetic acid across oil/water interface being the prerequisite that determines the occurrence and rate for the reactions and the structures and properties of final produced gel beads,a special emphasis was placed on the diffusion *** the aid of diffusion modeling and simple experimental design,the diffusion rate constant and diffusion coefficient of acetic acid across oil/water interface were determined to be in the orders of magnitude of 10-6 and 10-16,*** knowledge will be of particular importance in understanding and interpreting the formation,structure of the gel beads and the relationship between the structure and properties and guiding the preparation and quality control of the gel beads.

关键词： Emulsification-internal gelation technology Alginate Gel bead Diffusion rate constant Diffusion coefficient

Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques

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Nuclear Science and Techniques 2024年第6期35卷 78-89页

作者： Xian-Lin Yang Chang-Lin Lan yu-ting wei Yi Zhang Gong Jiang Bo Xie yu Liu Hong-Tao Shen Xiao-Jun Sun School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China

Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great *** address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion *** the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He ***^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of *** neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb *** measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature *** newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental *** obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc.

关键词： 14-MeV neutron ^(27)Al(n,2n)^(26)Al Cross section AMS

Consistency test of PMT SPE spectrum from dark-noise pulses and LED low-intensity light

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Radiation Detection Technology and Methods 2018年第1期2卷 76-79页

作者： yu-ting wei Meng-yun Guan wei-xing Xiong You-yu Gan Chang-gen Yang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of ScienceBeijingChina School of Physics University of Chinese Academy of ScienceBeijingChina

Photomultiplier tube(PMT)has been an essential instrument for low background experiments,and the accuracy of single photoelectron(SPE)calibration will directly affect the energy reconstruction of the *** SPE spectrum can be acquired from the charge distribution of dark-noise pulses or the low-intensity light signal triggered by ***,there are arguments on whether the two methods are *** this paper,the Hamamatsu R5912-20mod PMT and the EMID642KNFL PMT have been tested adopting the two methods with signal waveform recording *** comparison,traditional charge-to-digital conversion system is also used to test SPE *** results show that they are consistent when the PMTs are working at typical recommended high voltage(HV).

关键词： PMT SPE Dark noise LED Waveform

Prospects of detecting the reactor v_(e)-Ar coherent elastic scattering with a low-threshold dual-phase argon time projection chamber at Taishan

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Radiation Detection Technology and Methods 2021年第2期5卷 297-306页

作者： yu-ting wei Meng-yun Guan Jin-Chang Liu Ze-yuan yu Chang-Gen Yang Cong Guo wei-Xing Xiong You-yu Gan Qin Zhao Jia-Jun Li Institute of High Energy Physics CASBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China North China Electric Power University Beijing 100096China

Background We propose to measure the coherent elastic neutrino-nucleus scattering(CEvNS)using a dual-phase liquid argon time projection chamber(TPC)with 200 kg fiducial *** detector is expected to be adjacent to the JUNOTAO experiment and to be about 35 m from a reactor core with 4.6 GW thermal power at *** antineutrino flux is approximately 6×10^(12)cm^(−1)s^(−1) at this location,leading to more than 11,000 coherent scattering events per day in the fiducial *** The nuclear recoil energies concentrate in the sub-keV region,corresponding to less than ten ionization electrons in the liquid *** key question is how to veto and shield the background in the hall where the vertical overburden is about 5 *** what is the signal count rate and the background *** addition,what physical parameters can be measured what is the *** We used the Geant4 to simulate the backgrounds from cosmic ray muons and ambient radioactivity *** a veto and shielding design is *** a χ^(2) function is constructed and the sensitivity calculate package built to calculate the sensitivity of physical *** The detection of several ionization electrons can be achieved in the dual-phase TPC due to the large amplification in the gas *** a feasible detection threshold of four ionization electrons,the signal rate is 955 per *** detector is designed to be shielded well from cosmogenic backgrounds and ambient radioactivities to reach a 16%background-tosignal ratio in the energy region of *** the large CEvNS sample,the expected sensitivity of measuring the weak mixing angle sin^(2)θ_(w),and of limiting the neutrino magnetic moment are *** addition,a synergy between the reactor antineutrino CEvNS experiment and the dark matter experiment is foreseen.

关键词： Coherent elastic neutrino-nucleus scattering Dual-phase argon TPC Reactor antineutrinos

Calibration of liquid argon detector with ^(83m)Kr and ^(22)Na in different drift fields

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Radiation Detection Technology and Methods 2020年第2期4卷 147-152页

作者： wei-Xing Xiong Meng-yun Guan Chang-Gen Yang Peng Zhang Jin-Chang Liu Cong Guo yu-ting wei You-yu Gan Qing Zhao Jia-Jun Li Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China North China Electric Power University Beijing 100096China

Introduction Liquid noble gases are widely used as targets in low background search experiments,particularly in direct dark matter search experiments.83mKr is an excellent low-energy internal calibration source for future larger liquid noble gas *** To calibrate liquid argon detector with 83mKr in different drift fields and to study the correlation between light yield and drift *** A dual-phase LAr prototype detector was designed to study the 83mKr responses in liquid argon.83mKr atoms are produced through the decay of 83Rb and introduced into the LAr detector through the circulating purification *** We report that the light yield reaches 7.26±0.02 pe/keV for 41.5 keV from 83mKr and 7.66±0.01 pe/keV for 511 keV from 22Na,as a *** stopping the fill,the rate decays of 83mKr are with a fitted half-life of 1.83±0.11 h,which is consistent with the reported value of 1.83±0.02 *** light yield that varies with the drift electric field from 0 to 200 V/cm has also been reported.

关键词： Time projection chamber Noble liquid detectors Light yield Liquid argon

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公共研发投资对企业研发投入杠杆作用的研究

科学学研究 2017年第1期35卷 85-92页

作者：余伟婷蒋伏心南京师范大学商学院江苏南京210046 江苏省创新经济研究基地江苏南京210046

在我国,由政府支持的公共研发部门(主要包括高等院校和科研院所)和企业构成了社会研发系统。在此系统内,企业的研发投资决策变化,会影响公共研发投资杠杆作用的效果。本文运用FGLS方法,利用2009-2013年规模以上工业企业省际面板数据,从... 详细信息

在我国,由政府支持的公共研发部门(主要包括高等院校和科研院所)和企业构成了社会研发系统。在此系统内,企业的研发投资决策变化,会影响公共研发投资杠杆作用的效果。本文运用FGLS方法,利用2009-2013年规模以上工业企业省际面板数据,从社会研发系统的视角,探讨了当系统内企业受政府R&D资助强度变化时,公共研发投资对企业研发投入杠杆作用的变化。研究发现公共研发投资的杠杆作用存在区域差距,在政府对企业R&D资助强度大的地区,政府支持高等院校研发会促进本地区企业研发投入,且促进效应会因其对企业R&D资助强度大而加剧,但支持科研院所研发会挤出本地区企业研发投入;而在资助强度小的地区,影响则完全相反。因此各级政府在进行公共研发投资时应注意科技投入的精准化,合理搭配政策工具。

关键词：公共研发投资企业研发投入研发系统杠杆作用

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石墨烯/环氧复合材料导热性能的研究进展

高分子通报 2017年第9期 27-32页

作者：张玉伟沈育才王庭慰南京工业大学材料科学与工程学院南京210009

石墨烯作为时下最热门的纳米材料,吸引了国内外众多科研工作者的注意力。而石墨烯所具有的超高导热性能,使其在环氧导热复合材料中有着巨大的应用前景。本文主要综述了当前石墨烯/环氧复合材料导热性能的研究进展,详细介绍了石墨烯的尺... 详细信息

石墨烯作为时下最热门的纳米材料,吸引了国内外众多科研工作者的注意力。而石墨烯所具有的超高导热性能,使其在环氧导热复合材料中有着巨大的应用前景。本文主要综述了当前石墨烯/环氧复合材料导热性能的研究进展,详细介绍了石墨烯的尺寸、与其它填料的复配以及石墨烯表面改性等因素对导热性能的影响。此外,还分析了复合材料的微观结构对导热性能的影响。最后,对导热型石墨烯/环氧复合材料的发展进行了展望,并指出了该领域存在的技术难点和未知机理。

关键词：石墨烯环氧树脂表面改性导热性能

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海藻酸钠-壳聚糖复合膜中溶氧扩散性能研究

高校化学工程学报 2012年第3期26卷 429-435页

作者：赵伟张英于炜婷谢红国马小军中国科学院大连化学物理研究所生物医用材料工程组辽宁大连116023 中国科学院研究生院北京100049

氧气在微胶囊膜中的扩散行为将直接决定微囊内细胞的生长代谢行为。以海藻酸钠-壳聚糖聚电解质复合平板膜为研究模型,利用渗透池法,重点考察溶氧在膜中的扩散行为及其影响因素。结果显示:复合膜的扩散系数和孔隙率均低于海藻酸钙,复合... 详细信息

氧气在微胶囊膜中的扩散行为将直接决定微囊内细胞的生长代谢行为。以海藻酸钠-壳聚糖聚电解质复合平板膜为研究模型,利用渗透池法,重点考察溶氧在膜中的扩散行为及其影响因素。结果显示:复合膜的扩散系数和孔隙率均低于海藻酸钙,复合膜中溶氧扩散系数为(7～13)×10 10m2 s 1,为水中的23.3%～43.3%,孔隙率为93%～97%;扩散系数随海藻酸钠特性黏度的增大而减小,随壳聚糖分子量的增大而减小。微胶囊膜是氧传质主要的阻力部位,孔隙率、三维结构和材料极性是影响扩散性能的重要因素,改变海藻酸钠特性黏度和壳聚糖分子量可以改变膜孔隙率、结构和材料极性,进而调节膜扩散性能。

关键词：海藻酸钠-壳聚糖微胶囊海藻酸钠-壳聚糖聚电解质复合膜溶氧扩散系数孔隙率

微囊化对HepG2细胞渗透压调节基因表达影响及调控研究

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中国生物医学工程学报 2013年第1期32卷 70-77页

作者：肖静张英于玮婷王为马小军中国科学院大连化学物理研究所大连116023 南通大学公共卫生学院南通226019

探讨微囊微环境对HepG2细胞渗透压调节基因表达影响及抗渗透压物质干预效果。静电液滴法制备微囊化细胞,Real-time PCR法检测不同培养方式下钠/肌醇转运蛋白(SMIT)和牛磺酸转运蛋白(TAUT)基因表达;通过MTT法检测细胞活性、ELISA法检测... 详细信息

探讨微囊微环境对HepG2细胞渗透压调节基因表达影响及抗渗透压物质干预效果。静电液滴法制备微囊化细胞,Real-time PCR法检测不同培养方式下钠/肌醇转运蛋白(SMIT)和牛磺酸转运蛋白(TAUT)基因表达;通过MTT法检测细胞活性、ELISA法检测白蛋白含量,比较牛磺酸和海藻糖干预后指标变化。结果表明,不同培养方式间SMIT表达无显著差异;微囊化细胞TAUT表达增高,是平面细胞4.3倍(P<0.01);添加1～1.5 mM牛磺酸后,囊内细胞活性较对照组增加约15%～30%,白蛋白水平增加15%(P<0.05);海藻糖虽在0.1 mM时使囊内细胞活性增加20%～30%(P<0.05),但对白蛋白分泌水平无显著影响。微囊内存在高渗应激因素诱导基因表达改变,牛磺酸和海藻糖能拮抗其对细胞的抑制作用。

关键词：微囊化细胞钠肌醇转运蛋白牛磺酸转运蛋白渗透压应激

内质网应激对微囊化HepG2细胞脂代谢影响及调控研究

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中国生物医学工程学报 2013年第5期32卷 606-612页

作者：肖静张英于玮婷王为马小军中国科学院大连化学物理研究所生物医用材料工程组大连116023 南通大学公共卫生学院职业卫生与环境毒理学教研室南通226019

研究内质网应激发生对微囊化细胞脂代谢调节的影响,探讨内质网应激拮抗剂对微囊化细胞生长代谢调控的可行性。采用静电液滴法制备微囊化细胞,Real-time PCR法检测微囊化对葡萄糖调节蛋白78(GRP78)和C/EBP同源蛋白(CHOP)表达影响;通过MT... 详细信息

研究内质网应激发生对微囊化细胞脂代谢调节的影响,探讨内质网应激拮抗剂对微囊化细胞生长代谢调控的可行性。采用静电液滴法制备微囊化细胞,Real-time PCR法检测微囊化对葡萄糖调节蛋白78(GRP78)和C/EBP同源蛋白(CHOP)表达影响;通过MTT法检测细胞活性,ELISA法检测白蛋白含量,乙烷-丙酮法抽提测定胞内总胆固醇和甘油三酯含量,并比较拮抗剂四苯基丁酸(4-PBA)干预后相关指标变化。结果显示,微囊细胞中内质网应激标识蛋白GRP78和CHOP表达量分别为同天数下平面细胞3.6倍和1.9倍(P<0.05),胞内总胆固醇(CHO)和甘油三酯(TG)含量分别为平面细胞1.7倍和3.2倍(P<0.05)。内质网应激拮抗剂4-PBA在1.0 mM可显著增加微囊化细胞活性。干预后GRP78和CHOP基因表达水平降低50%和30%(P<0.05),胞内CHO和TG含量降低30%和15%(P<0.05),并使白蛋白水平较对照组显著提高(P<0.05)。结果提示微囊内存在内质网应激,且与微囊细胞脂代谢失调有关;内质网应激拮抗剂能缓解微囊对细胞的以上作用。

关键词：微囊化细胞内质网应激葡萄糖调节蛋白78 C EBP同源蛋白