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激光与光电子学进展 2018年第6期55卷 23-34页

作者：李云超胡旭文刘召军汤跃张彦军金文闫树斌中北大学仪器与电子学院山西太原030051 中北大学仪器科学与动态测试教育部重点实验室山西太原030051 中国航天科技集团公司北京100048

在微型定位、导航、授时(Micro-PNT)系统中,芯片原子钟(CSAC)作为微型时钟模块的核心,其发展关乎到Micro-PNT系统的定位精度与授时能力。原子气室作为芯片原子钟的"心脏",其制备工艺直接决定着原子钟的体积、稳定度与功耗等... 详细信息

在微型定位、导航、授时(Micro-PNT)系统中,芯片原子钟(CSAC)作为微型时钟模块的核心,其发展关乎到Micro-PNT系统的定位精度与授时能力。原子气室作为芯片原子钟的"心脏",其制备工艺直接决定着原子钟的体积、稳定度与功耗等多项性能指标。随着原子钟功耗的降低与体积的减小,加工制造出与之相适应的微型原子气室势在必行。从玻璃吹制法与微电子机械系统(MEMS)超精细加工法两个方面介绍了原子气室的加工工艺,综述了其研究进展,并分析了目前微型原子气室在制备工艺中存在的不足,对未来原子气室制备工艺的进一步优化具有一定的参考作用。

关键词：原子与分子物理学芯片原子钟原子气室导航定位授时

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铅锌矿区土壤重金属的淋溶试验研究

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矿业科学学报 2018年第4期3卷 406-416页

作者：张斯宇何绪文李焱房增强王浩中国矿业大学(北京)化学与环境工程学院北京100083 中国环境科学研究院水污染控制技术研究中心北京100012 工业和信息化部国际经济技术合作中心北京100846

为揭示铅锌矿区土壤重金属在淋溶条件下的环境行为,通过试验确定了淋溶条件下土壤中重金属的累积释放特征,利用一级动力学方程、修正的Elovich方程、双常数速率方程及抛物线扩散方程进行拟合,建立了淋溶条件下土壤中重金属的释放动力学... 详细信息

为揭示铅锌矿区土壤重金属在淋溶条件下的环境行为,通过试验确定了淋溶条件下土壤中重金属的累积释放特征,利用一级动力学方程、修正的Elovich方程、双常数速率方程及抛物线扩散方程进行拟合,建立了淋溶条件下土壤中重金属的释放动力学模型。结果表明:各重金属浸出浓度基本符合先升高后缓慢降低的趋势,其与淋溶体积及pH值之间存在一定负相关性,与电导率存在一定正相关性;土壤中各重金属残渣态比例明显提升,酸可提取态比例有所降低;各重金属的累积释放量增加速度逐渐缓慢。进行动力学方程拟合发现,除一级动力学方程外,其他3种方程对土壤中重金属淋滤过程的拟合结果均较好,说明模拟淋溶条件下土壤中重金属的释放过程不是简单的一级反应,而是一个由多因素综合控制的过程。

关键词：土壤淋溶重金属铅锌矿区释放动力学模型电导率

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芯片原子钟磁屏蔽系统的设计与仿真

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测试技术学报 2019年第4期33卷 334-339页

作者：胡旭文李云超张璐牟仕浩张开放刘召军张彦军闫树斌中北大学仪器与电子学院

为解决外部杂散磁场引起芯片原子钟跃迁谱线频移的问题,设计一款可用于原子钟测试实验的磁屏蔽装置.利用Matlab软件研究各结构参数对圆柱体磁屏蔽轴向屏蔽效能和球体磁屏蔽屏蔽效能的影响并进行比较,得出球体屏蔽效果优于圆柱体轴向屏... 详细信息

为解决外部杂散磁场引起芯片原子钟跃迁谱线频移的问题,设计一款可用于原子钟测试实验的磁屏蔽装置.利用Matlab软件研究各结构参数对圆柱体磁屏蔽轴向屏蔽效能和球体磁屏蔽屏蔽效能的影响并进行比较,得出球体屏蔽效果优于圆柱体轴向屏蔽效果的结论.使用有限元软件Maxwell对4个3层圆柱体和球体嵌套模型进行建模仿真,研究其内部剩余磁场大小和均匀度小于1%的区域.仿真结果表明,4个嵌套模型内部剩余磁场均小于10pT,满足原子钟对内部磁场的要求.其中,1层球体和2层圆柱体嵌套模型屏蔽效能可达139.04dB,具有最大的均匀度小于1%的范围约为22mm,可成为制作磁屏蔽的理想选择.该研究对磁屏蔽模型的设计提供了理论依据,为后续设计小尺寸磁屏蔽具有重要指导意义.

关键词：芯片原子钟频移屏蔽效能 Maxwell

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B30铜镍合金动态条件下在海水中腐蚀与结垢性能研究

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山东化工 2018年第21期47卷 45-48,51页

作者：范旭文赵桂锋张少峰刘燕颜开红河北工业大学化工学院天津300130 南通曙光新能源装备有限公司江苏南通226661

对B30铜镍合金在动态条件下的腐蚀与结垢性能进行了实验研究,研究了海水流速、温度以及热流密度变化对于铜镍合金腐蚀与结垢性能的影响。实验结果表明,随着海水流速、温度以及热流密度的增大,B30铜镍合金的腐蚀速率均表现出先增大后减... 详细信息

对B30铜镍合金在动态条件下的腐蚀与结垢性能进行了实验研究,研究了海水流速、温度以及热流密度变化对于铜镍合金腐蚀与结垢性能的影响。实验结果表明,随着海水流速、温度以及热流密度的增大,B30铜镍合金的腐蚀速率均表现出先增大后减小的趋势,而污垢热阻值则表现出先减小后增大的趋势。海水温度以及换热管热流密度的增大会减小垢层形成的诱导期,但是流速的增大会延长垢层形成的诱导期。在不同海水流速、温度以及热流密度条件下形成的完整的垢层对于B30铜镍合金的垢下腐蚀均有一定的防护作用,但是上述因素的变化主要影响B30铜镍合金的局部点蚀速率,只是在个别时间段对铜镍合金的腐蚀速率产生影响,而且当热流密度达到1000W·m-2时,初期松散的钙质沉积层会促进铜镍合金的局部点蚀速率。

关键词： B30铜镍合金海水腐蚀结垢

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Semisynthesis and bioactive evaluation of oxidized products from 20(S)-ginsenoside Rg₃, Rh₂, protopanaxadiol (PPD) and their 20(R)-epimers as cytotoxic agents

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STEROIDS 2016年 106卷 26-34页

作者： yang, Jie Li, xuwen Sun, Ting Gao, yan Chen, yanxin Jin, Yongri Li, yang Jilin Univ Coll Chem Changchun 130021 Peoples R China Jilin Univ Coll Life Sci Changchun 130012 Peoples R China

A series of oxidized products have been systematically semisynthesized from 20(S)-ginsenoside Rg(3), Rh-2, 20(S)-protopanaxadiol (PPD) and their 20(R)-epimers and the majority of these products were evaluated for their cytotoxic activity against HeLa cells and HepG2 cells by MIT assay for the first time. Twenty-two products were obtained and elucidated based on comprehensive H-1 NMR, C-13 NMR, two-dimensional (2D) NMR, and mass spectral data and the results reported in previous literature. All the four ocotillol type saponins (203,24R(delta 86, delta 85);205,24S(delta 87, delta 88);20R,24R(delta 86, delta 86);20R,245(delta 86, delta 87) were obtained. In addition, eight compounds (3, 8, 9, 10, 15, 16, 19 and 22) with the cyclized side chain were firstly identified. Most of the tested compounds possessed cytotoxicity to a certain degree against the two types of cells which implied these oxidized products could play a certain role on anti-cancer functions of the raw materials in vivo. Meanwhile, the results proved that the configurations at C-20 or C-24 and the number of glycosyl at C-3 have important influence on the cytotoxicity. The products 1, 2,11-17, 20 and 22 should possess great activities and deserved further investigation as potential cytotoxic agents. (C) 2015 Elsevier Inc. All rights reserved.

关键词： Semisynthesis Oxidation Ginsenoside Ocotillol Saponin Cytotoxicity

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Study on the treatment of wastewater containing Cu(II) by D851 ion exchange resin

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DESALINATION AND WATER TREATMENT 2016年第8期57卷 3597-3605页

作者： He, xuwen Fang, Zengqiang Jia, Jianli Ma, Lingshan Li, yan Chai, Zhen Chen, Xu China Univ Min & Technol Sch Chem & Environm Engn Beijing 100083 Peoples R China

A static adsorption experiment of copper ion was performed with D851 ion exchange resin to determine some optimum treatment parameters. The results of the experiment showed that the enthalpy value of the reaction was positive and the optimum reaction time was 60min, while the optimum pH value and reaction temperature were 5.5 and 35 degrees C, respectively. The adsorption equilibrium density of 0.1g ion exchange resin was between 75 and 100mg/L. With the condition of the hydraulic retention time of 60min, wastewater containing 10mg/L Cu(II) (pH approximate to 5.5) was treated by a dynamic ion exchange column, and the treatment effluent can meet the primary standard of the National Integrated Wastewater Discharge Standard (GB8978-1996). Meanwhile a desorption experiment with ion exchange resin was carried out, which determined that the optimum volume fraction of hydrochloric acid solution was 4% in the desorption solution. The figures of the scanning electron microscope showed that the resin saturated with Cu(II) could be regenerated well under the effect of hydrochloric acid solution, which was consistent with the experimental results.

关键词： Ion exchange resin Wastewater containing Cu(II) Static adsorption Dynamic adsorption Desorption experiment

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热应激对银鲫生化指标和HSP70 mRNA表达的影响

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渔业科学进展 2018年第6期39卷 65-71页

作者：周朝伟胡续雯雷骆刘晓庆任胜杰杨旻珉曹高祥陈国梁邓星星李岩李路宽西南大学动物科学学院水产系重庆402460

本研究旨在探讨热应激对银鲫(Carassius auratus gibelio)生化指标及肝脏HSP70 mRNA表达的影响,选取平均体重为(72.8±10.1) g的银鲫,分别在热应激前(25℃,对照组)、热应激后(32℃,0 h、2 h、6 h、10 h)和恢复适温后6 h (25℃,恢复... 详细信息

本研究旨在探讨热应激对银鲫(Carassius auratus gibelio)生化指标及肝脏HSP70 mRNA表达的影响,选取平均体重为(72.8±10.1) g的银鲫,分别在热应激前(25℃,对照组)、热应激后(32℃,0 h、2 h、6 h、10 h)和恢复适温后6 h (25℃,恢复组)的条件下,测定机体血浆乳酸(LD)、血浆葡萄糖(Glu)、肝糖原(Gly)、己糖激酶(HK)、丙酮酸激酶(PK)和肝脏HSP70 m RNA表达量变化。研究表明,实验组乳酸含量从热应激开始至恢复期,差异始终不显著(P>0.05);实验组血浆葡萄糖水平在热应激后0 h、2 h、6 h,极显著高于对照组(P<0.01);实验组肝糖原水平在热应激0 h时,极显著高于对照组(P<0.01),其余时间点差异不显著(P>0.05);己糖激酶活力在热应激后2 h,显著高于对照组(P>0.05);丙酮酸激酶活力在热应激后6h,极显著高于对照组(P<0.01);热应激后2h,肝脏中HSP70 m RNA表达量达到最高(P<0.01),恢复至适温后,表达量与应激前无差异(P>0.05)。本研究为进一步探究银鲫的高温应激作用机制及调控机理提供参考数据,同时,也为银鲫养殖和育种等生产实践提供相应参考依据。

关键词：银鲫热应激生化指标 HSP70

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CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi Yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai Yijian Cai Yizhou Cai Yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao Jianshe Cao Antoine Chance Xuejun Chang Yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che Yuzhi Che Bin Chen Danping Chen Fuqing Chen Fusan Chen Gang Chen Guoming Chen Hua-Xing Chen Huirun Chen Jinhui Chen Ji-Yuan Chen Kai Chen Mali Chen Mingjun Chen Mingshui Chen Ning Chen Shanhong Chen Shanzhen Chen Shao-Long Chen Shaomin Chen Shiqiang Chen Tianlu Chen Wei Chen Xiang Chen Xiaoyu Chen Xin Chen Xun Chen Xurong Chen Ye Chen Ying Chen Yukai Chen Zelin Chen Zilin Chen Gang Chen Boping Chen Chunhui Chen Hok Chuen Cheng Huajie Cheng Shan Cheng Tongguang Cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi Ling-Yun Dai Xinchen Dai xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH University of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui University HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu University Institute of ScienceVaranasi Bandirma Onyedi Eylul University Bandirma Beihang University Beijing Beijing Computational Science Research Center Beijing Beijing Conveyi LTD Beijing Beijing Glass Research Institute Co. LtdBeijing Beijing Institute of Technology Beijing Beijing Normal University Beijing Brown University ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad University Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo University Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central China Normal University WuhanHubei Central South University ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa Chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan China academy of engineering physics MianyangSichuan China building materials academy Beijing China Center of Advanced Science and Technology Beijing China Institute of Atomic Energy Beijing China Jiliang University HangzhouZhejiang China Nuclear Instrument CO. LTDBeijing China University of Geosciences Beijing China University of Geosciences WuhanHubei China University of Mining and Technology XuzhouJiangsu China West Normal University NanchongSichuan Chongqing University Department of PhysicsChongqing Chulalongkorn University Bangkok City University of Hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell University IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu University DalianLiaoning Dalian University of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP JINR) Dubna East China University Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by China,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2030s.

关键词： initiated exceeding precise

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Tumor Suppressor Folliculin Regulates mTORC1 through Primary Cilia

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JOURNAL OF BIOLOGICAL CHEMISTRY 2016年第22期291卷 11689-11697页

作者： Zhong, Mingming Zhao, xuwen Li, Jinmei Yuan, Wenjie yan, Gonghong Tong, Mingming Guo, Shuguang Zhu, Yichao Jiang, Yong Liu, Yongjian Jiang, Yu Southern Med Univ Minist Educ China State Key Lab Organ Failure ResDept Pathophysiol Key Lab Transcript & ProteGuangdong Prov Key Lab Guangzhou 510515 Guangdong Peoples R China Univ Pittsburgh Sch Med Dept Pharmacol & Chem Biol Pittsburgh PA 15261 USA Nanjing Med Univ Dept Physiol Nanjing 211166 Jiangsu Peoples R China

Folliculin (FLCN) is the tumor suppressor associated with Birt-Hogg-Dube (BHD) syndrome that predisposes patients to incident of hamartomas and cysts in multiple organs. Its inactivation causes deregulation in the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway. However, the underlying mechanism is poorly defined. In this study, we show that FLCN is a ciliary protein that functions through primary cilia to regulate mTORC1. In response to flow stress, FLCN associates with LKB1 and recruits the kinase to primary cilia for activation of AMPK resided at basal bodies, which causes mTORC1 down-regulation. In cells depleted of FLCN, LKB1 fails to accumulate in primary cilia and AMPK at the basal bodies remains inactive, thus nullifying the inhibitory effect of flow stress on mTORC1 activity. Our results demonstrate that FLCN is part of a flow sensory mechanism that regulates mTORC1 through primary cilia.

关键词： AMP-activated kinase (AMPK) mammalian target of rapamycin (mTOR) mTOR complex (mTORC) primary cilium tumor suppressor gene FLCN LKB1 folliculin

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Molecular mechanism of endocrine system impairment by 17α-methyltestosterone in gynogenic Pengze crucian carp offspring

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ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2016年 128卷 143-152页

作者： Zheng, Yao Chen, Jiazhang Liu, yan Gao, Jiancao yang, yanping Zhang, Yingying Bing, xuwen Gao, Zexia Liang, Hongwei Wang, Zaizhao Northwest A&F Univ Coll Anim Sci & Technol Shaanxi Key Lab Mol Biol Agr Yangling 712100 Shaanxi Peoples R China Chinese Acad Fishery Sci Key Open Lab Ecol Environm & Resources Inland Fis Freshwater Fisheries Res Ctr Beijing Peoples R China Minist Agr Key Lab Genet Breeding & Aquaculture Biol Freshwa Sci Observing & Expt Stn Fishery Resources & Envi Beijing Peoples R China Nanjing Agr Univ Wuxi Fisheries Coll Wuxi 214081 Peoples R China HZAU Minist Agr Key Lab Freshwater Anim Breeding Wuhan 430070 Peoples R China Chinese Acad Fishery Sci Yangtze River Fisheries Res Inst Wuhan 430223 Hubei Peoples R China

The effects of synthetic androgen 17 alpha-methyltestosterone (MT) on endocrine impairment were examined in crucian carp. Immature 7-month old mono-female Pengze crucian carp (Pcc) F2 offspring were exposed to 50 and 100 mu g/L of MT (week 2, 4, and 8). Gonadosomatic index, hepatosomatic index and intestine weight altered considerably and oocyte development was repressed. In the treatment groups, ovarian 11-ketotestosterone decreased, whereas 17 beta-estradiol and testosterone increased, and ovarian aromatase activities increased at week 4. However, in the brain tissue, those values, significantly decreased. Quantitative RT-PCR analysis demonstrated changes in steroid receptor genes and upregulation of steroidogenic genes (Pcc-3bhsd, Pcc-11bhsd2 Pcc-cyp11 alpha 1), while the other three steroidogenic genes (Pcc-cyp17 alpha 1, Pcc-cyp19a1a and Pcc-star) decreased from week 4 to week 8. Ovarian, hepatic Pcc-vtg B and vitellogenin concentration increased in both 50 and 100 a of MT exposure groups. This study adds further information regarding the effects of androgens on the development of previtellogenic oocytes, which suggests that MT could directly target estrogen signaling pathway, or indirectly affect steroidogenesis and vitellogenesis. (C) 2016 Elsevier Inc. All rights reserved.

关键词： 17 alpha-methyltestosterone Estrogen signalling Gynogenic Pengze crucian carp Steroid hormones Steroidogenesis Vitellogenesis

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