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Optimal squeezed cooling of a mechanical oscillator using measurement-based vector feedback

Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 55-61页

作者： Zhi-Cheng Gong Cheng-Yu Shen Tian-Hua Mao chang-pu Sun Yong Li Hao Fu School of Science Hainan UniversityHaikou 570228China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100190China Graduate School of China Academy of Engineering Physics Beijing 100193China Beijing Computational Science Research Center Beijing 100193China Center for Theoretical Physics Hainan UniversityHaikou 570228China

Measurement-based feedback has been adopted as an efficient cooling scheme capable of suppressing the thermal fluctuation of a mechanical resonator to a level limited by measurement *** present a scheme of squeezed cooling in which the limit of feedback cooling imposed by the measurement imprecision is surpassed by parametrically squeezing the mechanical resonator in a periodically oscillating optical *** stabilize the parametrically amplified quadrature and simultaneously optimize the cooling for the squeezed quadrature,a measurement-based vector feedback capable of independently controlling the orthogonal motional quadrature is *** experiment demonstrates that the optimal condition for the squeezed cooling closely depends on the strength of *** the ability to keep the orthogonal quadrature well decoupled,optimal squeezed cooling of the mechanical resonator under strong squeezing is achieved with the squeezed variance becoming 8.1 dB below the limit of feedback cooling and the creation of a 31.7 dB thermomechanical squeezed *** this research is conducted in the classical regime,the scheme of squeezed cooling can be naturally extended to quantum systems with the prospects of creating quantum squeezing of a room-temperature mechanical resonator and enabling displacement measurement beyond the standard quantum limit.

关键词： squeezed cooling measurement-based feedback parametric squeezing optimal control optomechanics

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Readout electronics of a prototype spectrometer for measuring low-energy ions in solar wind plasma

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Nuclear Science and Techniques 2016年第6期27卷 130-136页

作者： Di Yang zhe Cao Xi Qin Xin-Jun Hao Shu-Bin Liu chang-Qing Feng Qi An State Key Laboratory of Particle Detection and Electronics(IHEP-USTC) Hefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Division of Space Physics University of Science andTechnology of ChinaHefei 230026China CAS Key Laboratory of Geospace Environment Hefei 230026China

Readout electronics is developed for a prototype spectrometer for in situ measurement of low-energy ions of30 e V/e–20 ke V/e in the solar wind plasma.A low-noise preamplifier/discriminator(A111F) is employed for each channel to process the signal from micro-channel plate(MCP) detectors.A high-voltage(HV) supply solution based on a HV module and a HV optocoupler is adopted to generate a fast sweeping HV and a fixed *** to limitation of telemetry bandwidth in space communication,an algorithm is implemented in an FPGA(field programmable gate array) to compress the raw *** results show that the electronics achieves a 1 MHz event rate and a large input dynamic range of 95 p C.A slew rate of 0.8 V/ls and an integral nonlinearity of 0.7-LSB for the sweeping HV,and a precision of less than 0.8 % for the fixed HV are obtained.A vacuum beam test shows an energy resolution of 12 ± 0.7 % full width at half maximum(FWHM) is achieved,and noise counts are less than10/sec,indicating that the performance meets the physical requirement.

关键词：低能离子等离子体原位测量电子学光谱仪太阳风读出原型

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Overcoming the limitation of in-situ microstructural control in laser additive manufactured Ti-6Al-4V alloy to enhanced mechanical performance by integration of synchronous induction heating

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Journal of Materials Science & Technology 2021年第35期94卷 32-46页

作者： Wei Fan Hua Tan Fengying Zhang zhe Feng Yongxia Wang Lai-chang Zhang Xin Lin Weidong Huang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi'an 710072China School of Material Science and Engineering Chang'an UniversityXi'an 710064China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia

Although a variety of processing routes were developed to in-situ manipulate microstructure for fabricating high-performance Ti-6Al-4 V alloy by directed energy deposition(DED),the in-situ microstructural control ability has been limited and lead to a narrowed mechanical property control *** work proved the microstructural correlation betweenβ-grains andα-laths resulting from the unique thermal characteristics of DED for the first time and solved such a dilemma through synchronous induction heating assisted laser deposition(SILD)*** results confirmed that the laser energy and inductive energy have a different effect on the solidification and solid phase transformation *** adjusting the laser-induction parameters,the microstructural correlation can be tuned;theβ-grains andα-laths can be controlled relatively separately,thereby significantly enhancing the ductility of as-deposited sample(elongation from 14.2%to 20.1%).Furthermore,the mechanical properties of the tuned microstructures are even comparable to that of DED Ti-6Al-4 V with post heat treatment,which indicates that the potential of SILD to be a one-step manufacturing process to fabricate high performance components without post heat ***,the tensile testing results of the tuned microstructures indicate thatα-lath size is more influential on the mechanical properties than theβ-grain size due to its stronger hindering effect on the slipping of *** work promotes the understanding of the microstructural formation mechanism in DED titanium alloy and proves that the combination of synchronous induction and laser can expand the ability to control the microstructure and properties of multi-layer deposition.

关键词： Directed energy deposition Additive manufacturing Ti-6Al-4V In-situ microstructural control Mechanical properties

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西湖凹陷平南地区新生代火山机构特征

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煤田地质与勘探 2025年第1期53卷 215-225页

作者：孙乃泉江东辉潘杰高阳蒲仁海董新旭长安大学地质工程与测绘学院陕西西安710054 中国石油化工股份有限公司上海海洋油气分公司上海200120 西北大学大陆动力学国家重点实验室陕西西安710069 西北大学地质学系陕西西安710069 攀枝花学院数学与计算机学院四川攀枝花617000

【研究意义】东海陆架盆地西湖凹陷平湖斜坡带南部火成岩发育,岩浆活动导致的局部地温升高对烃源岩热演化和砂岩储层次生孔隙形成具有重要影响,同时也是区域构造运动的一个重要指示,对于理解区域地质历史具有重要意义。【目的和方法】... 详细信息

【研究意义】东海陆架盆地西湖凹陷平湖斜坡带南部火成岩发育,岩浆活动导致的局部地温升高对烃源岩热演化和砂岩储层次生孔隙形成具有重要影响,同时也是区域构造运动的一个重要指示,对于理解区域地质历史具有重要意义。【目的和方法】为明确西湖凹陷平湖斜坡带南部盖层火成岩形成期次和分布规律,综合前人研究成果和邻区数据,利用三维地震数据及相关属性,结合钻井、录井和测井资料,分析了火山岩类型、分布地层和范围;通过地层年代学、火山机构形态及其与围岩的接触关系,探讨了火成岩的形成期次。【结果和结论】研究结果表明:(1)平南地区火成岩地震相可分为火山通道相、爆发相、溢流相和侵入相,其中盾状火山机构和丘状火山机构最为发育。(2)岩浆活动可分为3期,中新世末期区域性龙井运动岩浆活动最为强烈,影响范围最广;玉泉组沉积晚期和三潭组沉积早期为局部小规模构造运动,岩浆活动较弱,影响较小。(3)研究区发育5个与岩浆活动有关的岩性、低幅度披覆背斜和断裂复合圈闭。研究成果为后续西湖凹陷平湖斜坡带南部油气勘探开发提供参考。

关键词：西湖凹陷岩浆活动火山机构地震响应特征

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大麻二酚对脂多糖诱导的小鼠乳腺上皮细胞炎症反应和凋亡的抑制作用

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中国畜牧兽医 2025年第1期52卷 60-69页

作者：常欣欣黄鑫范港杨佳欣张伟伟杨清竹田哲齐齐哈尔大学生命科学与农林学院齐齐哈尔161006 齐齐哈尔大学寒区麻及制品教育部工程研究中心齐齐哈尔161006 黑龙江省农用生物制剂产业化协同创新中心齐齐哈尔161006

[目的]研究大麻二酚(CBD)对脂多糖(LPS)诱导的小鼠乳腺上皮细胞(HC11)炎症反应及细胞凋亡的影响。[方法]试验将HC11细胞分为对照组、LPS组和不同浓度CBD+LPS共处理组(CBD浓度分别为2、4、6μmol/L)。对照组细胞仅加入培养液,LPS组加入LP... 详细信息

[目的]研究大麻二酚(CBD)对脂多糖(LPS)诱导的小鼠乳腺上皮细胞(HC11)炎症反应及细胞凋亡的影响。[方法]试验将HC11细胞分为对照组、LPS组和不同浓度CBD+LPS共处理组(CBD浓度分别为2、4、6μmol/L)。对照组细胞仅加入培养液,LPS组加入LPS处理,CBD+LPS共处理组用不同浓度CBD预处理1 h后加入LPS,24 h后收集各组细胞样品。利用ELISA法检测细胞中炎症因子含量;使用实时荧光定量PCR、Western blotting分别检测细胞炎症因子及核因子κB(NF-κB)、丝裂原活化蛋白激酶(MAPK)信号通路相关基因mRNA和蛋白的表达水平;通过AnnexinV-FITC/碘化丙啶(PI)和JC-1染色法分别检测细胞凋亡率和线粒体膜电位水平。[结果]与对照组相比,LPS组细胞中肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、IL-6含量及mRNA表达水平均极显著或显著升高(P<0.01;P<0.05),NF-κB p65、核因子-κB抑制蛋白α(IκBα)、细胞外信号调节激酶(ERK)、丝裂原活化蛋白激酶(p38)、应激活化蛋白激酶(JNK)的mRNA表达量和蛋白磷酸化水平极显著或显著升高(P<0.01;P<0.05)。与LPS组相比,不同浓度CBD与LPS共处理后细胞中TNF-α、IL-1β、IL-6含量及mRNA表达量均极显著或显著降低(P<0.01;P<0.05),NF-κB p65、IκBα、ERK、p38、JNK的mRNA表达量和蛋白磷酸化水平均极显著或显著降低(P<0.01;P<0.05)。细胞凋亡率和线粒体膜电位检测结果显示,与对照组相比,LPS组HC11细胞凋亡率显著升高(P<0.05),线粒体膜电位显著降低(P<0.05)。与LPS组相比,4μmol/L CBD和LPS共处理后,HC11细胞凋亡率显著降低(P<0.05),线粒体膜电位显著升高(P<0.05)。[结论]在LPS诱导的小鼠HC11细胞炎症及凋亡模型中,适宜浓度CBD能抑制NF-κB和MAPK信号通路的激活,从而抑制炎症因子的释放来缓解炎症反应;同时能降低LPS诱导的HC11细胞凋亡率、上调细胞线粒体膜电位,从而抑制细胞凋亡发生。

关键词：大麻二酚脂多糖小鼠乳腺上皮细胞炎症反应细胞凋亡

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Exosomes from bone marrow mesenchymal stem cells are a potential treatment for ischemic stroke

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Neural Regeneration Research 2023年第10期18卷 2246-2251页

作者： chang Liu Tian-Hui Yang Hong-Dan Li Gong-zhe Li Jia Liang Peng Wang Liaoning Provincial Key Laboratory of Neurodegenerative Diseases and Department of Neurobiology Jinzhou Medical UniversityJinzhouLiaoning ProvinceChina Institute of Life Science Jinzhou Medical UniversityJinzhouLiaoning ProvinceChina College of Pharmacy Jinzhou Medical UniversityJinzhouLiaoning ProvinceChina

Exosomes derived from human bone marrow mesenchymal stem cells(MSC-Exo)are characterized by easy expansion and storage,low risk of tumor formation,low immunogenicity,and anti-inflammatory *** therapeutic effects of MSC-Exo on ischemic stroke have been widely ***,the underlying mechanism remains *** this study,we established a mouse model of ischemic brain injury induced by occlusion of the middle cerebral artery using the thread bolt method and injected MSC-Exo into the tail *** found that administration of MSC-Exo reduced the volume of cerebral infarction in the ischemic brain injury mouse model,increased the levels of interleukin-33(IL-33)and suppression of tumorigenicity 2 receptor(ST2)in the penumbra of cerebral infarction,and improved neurological *** vitro results showed that astrocyte-conditioned medium of cells deprived of both oxygen and glucose,to simulate ischemia conditions,combined with MSC-Exo increased the survival rate of primary cortical ***,after transfection by IL-33 siRNA or ST2 siRNA,the survival rate of primary cortical neurons was markedly *** results indicated that MSC-Exo inhibited neuronal death induced by oxygen and glucose deprivation through the IL-33/ST2 signaling pathway in *** findings suggest that MSC-Exo may reduce ischemia-induced brain injury through regulating the IL-33/ST2 signaling ***,MSC-Exo may be a potential therapeutic method for ischemic stroke.

关键词： astrocytes bone marrow mesenchymal stem cells brain injury exosome IL-33 inflammation ischemic stroke neurological function neuron ST2

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Searching for a possible dipole anisotropy in acceleration scale with 147 rotationally supported galaxies

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Chinese Physics C 2018年第11期42卷 137-144页

作者： zhe chang Hai-Nan Lin Zhi-Chao Zhao Yong Zhou Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China

We report a possible dipole anisotropy in acceleration scale g↑ with 147 rotationally supported galaxies in the local Universe. It is found that a monopole and dipole correction for the radial acceleration relation can better describe the SPARC data set. The monopole term is negligible but the dipole magnitude is significant. It is also found that the dipole correction is mostly induced by anisotropy in the acceleration scale. The magnitude of the g↑-dipole reaches 0.25±0.04, and its direction is aligned to （l,b）=（171.30°±7.18°,-15.41°±4.87°）, which is very close to the maximum anisotropy direction from the hemisphere comparison method. Furthermore, a robust check shows that the dipole anisotropy could not be reproduced by an isotropic mock data set. However, it is still premature to claim that the Universe is anisotropic, due to the small data samples and uncertainty in the current observations.

关键词： galaxies kinematics and dynamics galaxies fundamental parameters large-scale structure of Universe

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Fabrication of tungsten films by metallorganic chemical vapor deposition

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International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1149-1153页

作者： Yi Li Jin-pu Li Cheng-chang Jia Xue-quan Liu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Powder Metallurgy Laboratory Central Iron & Steel Research Institute Beijing 100081 China

Tungsten films growing on copper substrates were fabricated by metallorganic chemical vapor deposition （MOCVD）. The chemi-cal purity, crystallographic phase, cross-sectional texture, and resistivity of the deposited films both before and after annealing treatment were investigated by X-ray energy-dispersive spectroscopy （EDS）, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and four-point probe method. It is found that the films deposited at 460°C are metastable β-W with （211） orientation and can change into α-W when an-nealed in high-purity hydrogen atmosphere at high temperature. There are small amounts of C and O in the films, and the W content of the films increases with increasing deposition temperature and also goes up after annealing in high-purity hydrogen atmosphere. The films have columnar microstructures and the texture evolution during their growth on copper substrates can be divided into three stages. The resistivity of the as-deposited films is in the range of 87-104 μΩ·cm, and low resistivity is obtained after annealing in high-purity hydrogen atmosphere.

关键词： thin films tungsten metallorganic chemical vapor deposition crystallography textures electric properties

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Structural basis for the recognition of RNA polymerase II C-terminal domain by CREPT and p15RS

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Science China(Life Sciences) 2014年第1期57卷 97-106页

作者： MEI KunRong JIN zhe REN FangLi WANG YinYing chang ZhiJie WANG XinQuan Ministry of Education Key Laboratory of Protein Science Center for Structure Biology School of Life Sciences Tsinghua University State Key Laboratory of Biomembrane and Membrane Biotechnology School of Medicine Tsinghua University

CREPT and p15RS are two recently identified homologous proteins that regulate cell proliferation in an opposite way and are closely related to human cancer development. Both CREPT and pl5RS consist of an N-terminal RPR domain and a C-terminal domain with high sequence homology. The transcription enhancement by CREPT is attributed to its interaction with RNA polymerase II （Pol II）. Here we provide biochemical and structural evidence to support and extend this molecular mechanism. Through fluorescence polarization analysis, we show that the RPR domains of CREPT and pl5RS （CREPT-RPR and pI5RS-RPR） bind to different Pol II C-terminal domain （CTD） phosphoisoforms with similar affinity and specificity. We also determined the crystal structure of pl5RS-RPR. Sequence and structural comparisons with RPR domain of Rttl03, a homolog of CREPT and p l5RS in yeast, reveal structural basis for the similar binding profile of CREPT-RPR and p 15RS-RPR with Pol II CTD. We also determined the crystal structure of the C-terminal domain of CREPT （CREPT-CTD）, which is a long rod-like dimer and each monomer adopts a coiled-coil structure. We propose that dimerization through the C-terminal domain enhances the binding strength between CREPT or pl5RS with Pol II by increasing binding avidity. Our results collectively reveal the respective roles of N-terminal RPR domain and C-terminal domain of CREPT and pl5RS in recognizing RNA Pol II.

关键词： CREPT p15RS structure RPR domain C-terminal domain RNA Pol II

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Synthesis and properties of novel soluble poly(aryl amine ketone)s as high-performance polymers

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Science China Chemistry 2008年第3期51卷 275-281页

作者： chang GuanJun TANG Shizhen LUO Xuan WANG Qiang XU zhe ZHANG Lin LIN RunXiong Key Laboratory of Rubber-plastics Ministry of EducationQingdao University of Science and TechnologyQingdao 266042China Resarch Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900China College of Engineering Ocean University of ChinaQingdao 266100China

A series of poly(aryl amine ketone)s have been obtained by the condensation polymerization of different aromatic dibromides with different primary aromatic diamines via palladium-catalyzed aryl amination reaction. The structures of polymers are characterized by means of FT-IR, 1H NMR spectroscopy, and elemental analysis. The results show an agreement with the proposed structures. DSC and TG measurements show that polymers possess high glass transition temperature (T g>170°C) and good thermal stability with high decomposition temperatures (T D>450°C). These novel polymers also exhibit good mechanical behaviors and good solubility.

关键词： aromatic dibromides aromatic diamines palladium-catalyzed poly(aryl amine ketone)

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