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离子液体-水体系的相平衡

高校化学工程学报 2008年第4期22卷 553-556页

作者：田勇王秀芳王键吉广东药学院药科学院广东广州510006 河南师范大学化学与环境学院河南新乡453002

通过对1-丁基-3-甲基咪唑四氟硼酸盐([bmim][PF4])离子液体+水体系相平衡及NaCl、NaBF4和氯化1-丁基-3-甲基咪唑([bmim]Cl)对离子液体+水体系相平衡的影响进行了研究,结果表明:离子液体[bmim][BF4]+H2O二元体系具有典型的最高上临界溶... 详细信息

通过对1-丁基-3-甲基咪唑四氟硼酸盐([bmim][PF4])离子液体+水体系相平衡及NaCl、NaBF4和氯化1-丁基-3-甲基咪唑([bmim]Cl)对离子液体+水体系相平衡的影响进行了研究,结果表明:离子液体[bmim][BF4]+H2O二元体系具有典型的最高上临界溶解温度(UCST)行为,其最高上临界温度为5.3℃左右,临界组成为50%(水的质量分数);NaCl和NaBF4降低[bmim][BF4]+H2O体系的混溶性,而[bmim]Cl增加该体系的混溶性。由此得到一种简单定性地判断离子液体[bmim][BF4]中可能存在的杂质种类和水平的方法,并利用此结果可设计纯化该离子液体的绿色工艺。

关键词：离子液体 1-丁基-3-甲基咪唑四氟硼酸盐相平衡混溶温度

α-生育酚琥珀酸酯通过线粒体诱导肿瘤细胞凋亡的研究

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肿瘤 2010年第7期30卷 628-630页

作者：谢英王秀芳河北医科大学实验动物学部河北省实验动物重点实验室石家庄050017

α-生育酚琥珀酸酯(α-tocopheryl succinate,α-TOS)是一种有潜力的细胞凋亡诱导剂,可以诱导人类以及小鼠多种肿瘤细胞凋亡。α-TOS进入细胞后,特异性进入线粒体内,替代结合在线粒体内膜复合体Ⅱ上的辅酶Q,引起线粒体活性氧(re-active ... 详细信息

α-生育酚琥珀酸酯(α-tocopheryl succinate,α-TOS)是一种有潜力的细胞凋亡诱导剂,可以诱导人类以及小鼠多种肿瘤细胞凋亡。α-TOS进入细胞后,特异性进入线粒体内,替代结合在线粒体内膜复合体Ⅱ上的辅酶Q,引起线粒体活性氧(re-active oxygen species,ROS)的产生,随后由ROS促使细胞质中的凋亡相关蛋白Bax形成由二硫键连接的二聚体,这些二聚体结合到线粒体的外膜(mitochondrial outer membrane,MOM)上,形成通道,促使线粒体内的细胞色素C(cytochrome C,Cyt C)从这些通道穿过,转位到细胞质中,级联激活位于细胞质中的caspase,引起细胞凋亡。本文就α-TOS诱导肿瘤细胞凋亡的线粒体途径进行综述。

关键词：肿瘤生育酚类线粒体细胞凋亡

Analytical Solution and Simplified Formula for Added Mass of Horizontal and Vertical Motions of Truncated Cylinders Under Earthquake Action

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China Ocean Engineering 2024年第1期38卷 54-67页

作者： wang Pi-guang LYU Si-yu QU Yang ZHAO Mi DU xiu-li State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of Tech-nologyBeijing 100124China

This paper investigates the hydrodynamic characteristics of floating truncated cylinders undergoing horizontal and vertical motions due to earthquake excitations in the finite water *** governing equation of the hydrodynamic pressure acting on the cylinder is derived based on the radiation theory with the inviscid and incompressible *** governing equation is solved by using the method of separating variables and analytical solutions are obtained by assigning reasonable boundary *** analytical result is validated by a numerical model using the exact artificial boundary simulation of the infinite *** main variation and distribution characteristics of the hydrodynamic pressure acting on the side and bottom of the cylinder are analyzed for different combinations of wide-height and immersion *** added mass coefficient of the cylinder is calculated by integrating the hydrodynamic pressure and simplified formulas are proposed for engineering *** calculation results show that the simplified formulas are in good agreement with the analytical solutions.

关键词： earthquake hydrodynamic pressure truncated cylinder added mass simplified formula

Data-driven discovery of linear dynamical systems from noisy data

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Science China(Technological Sciences) 2024年第1期67卷 121-129页

作者： wang YaSen YUAN Ye fang HuaZhen DING Han School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering University of KansasLawrence 66045USA

In modern science and engineering disciplines,data-driven discovery methods play a fundamental role in system modeling,as data serve as the external representations of the intrinsic mechanisms within ***,empirical data contaminated by process and measurement noise remain a significant obstacle for this type of *** this study,we have developed a data-driven method capable of directly uncovering linear dynamical systems from noisy *** method combines the Kalman smoothing and sparse Bayesian learning to decouple process and measurement noise under the expectation-maximization framework,presenting an analytical method for alternate state estimation and system ***,the discovered model explicitly characterizes the probability distribution of process and measurement noise,as they are essential for filtering,smoothing,and stochastic *** have successfully applied the proposed algorithm to several simulation *** results demonstrate its potential to enable linear dynamical system discovery in practical applications where noise-free data are intractable to capture.

关键词： system identification sparse Bayesian learning Kalman smoothing process and measurement noise

Long-wave infrared emission properties of strain-balanced InAs/In_(x)Ga_(1-x)As_(y)Sb_(1-y)type-Ⅱsuperlattice on different substrates

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Rare Metals 2024年第7期43卷 3194-3204页

作者： Chao Shi Xuan fang Hong-Bin Zhao Deng-Kui wang Xi Chen Dan fang Dong-Bo wang Xiao-Hua wang Jin-Hua Li State Key Laboratory of High Power Semiconductor Lasers School of PhysicsChangchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Advanced Materials for Smart Sensing China General Research Institute for Nonferrous MetalsBeijing 100088China Department of Opto-Electronic Information Science School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

High-performance type-Ⅱsuperlattices ofⅢ-Ⅴsemiconductor materials play an important role in the development and application of infrared optoelectronic *** the quality of epitaxial materials and clarifying the luminescent mechanism are of great significance for practic al applic *** this work,strain-balanced and high-quality In As/In_(x)Ga_(1-x)As_(y)Sb_(1-y)superlattices without lattice mismatch were achieved on InAs and GaSb substrates *** grown on In As substrate could exhibit higher crystal quality and surface flatness based on high-resolution X-ray diffraction(HRXRD)and atomic force microscopy(AFM)measurements'***,the strain distribution phenomenon from geometric phase analysis indicates that fluctuations of alloy compositions in superlattices on GaSb substrate are more *** addition,the optical properties of superlattices grown on different substrates are discussed *** of the difference in fluctuations of element composition and interface roughness of superlattices on different substrates,the superlattices grown on In As substrate would have higher integral intensity and narrower full-width at half maximum of long-wave infrared ***,the thermal quenching of emission intensity indicates that the superlattices grown on the In As substrate have better recombination ability,which is beneficial for increasing the operating temperature of infrared optoelectronic devices based on this type of superlattices.

关键词： Photoluminescence Alloy compositions fluctuations InAs(Sb)/In_(x)Ga_(1-x)As_(y)Sb_(1-y) Type-Ⅱsuperlattice Substrate

Advance in reversible Zn anodes promoted by 2D materials

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Rare Metals 2024年第4期43卷 1350-1369页

作者： Shu-Yuan Lei Jin-xiu Feng Yu-Chao Chen Dong Zheng Wen-Xian Liu Wen-Hui Shi fang-fang Wu Xie-Hong Cao School of Materials Science and Engineering Zhejiang University of TechnologyHangzhou310014China Center for Membrane Separation and Water Science and Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

With the growing energy demand associated with high safety and low-cost requirement,aqueous zinc-ion batteries(AZIBs)have been considered as one of the most promising next-generation ***,some key issues,such as uncontrollable dendrites growth,severe corrosion,hydrogen evolution and side reactions of Zn anodes during charge/discharge process,have hindered its pragmatic ***-dimensional(2D)materials hold advantages of unique physical and chemical properties,large surface areas and abundant active sites,which have been successfully used to overcome the above shortcomings of Zn anodes in recent *** this review,the issues and challenges of Zn anodes are ***,the state-of-the-art progress on Zn anodes modification based on 2D materials such as graphene,2D metal carbides and nitrides(MXenes),2D metal-organic frameworks(MOFs),2D covalent organic frameworks(COFs),2D transition metal compounds and other 2D materials is discussed in ***,the perspectives of employing 2D materials in highly reversible Zn anodes are summarized and discussed.

关键词： 2D materials Aqueous zinc-ion battery Zn anodes Dendrites growth

Grain size effect on the assembly quality of micro-scaled barrel formed by microforming

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Advances in Manufacturing 2024年第1期12卷 19-32页

作者： Dien Hu Jieyichen fang Feng Zeng Ming-wang Fu Department of Mechanical Engineering Research Institute of Advanced ManufacturingThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Xiamen Yulong Machinery Co.Ltd. Xiamen361023FujianPeople’s Republic of China

In this research,a method employing micro-extrusion was designed to produce the micro-scaled barrel-shaped parts with complex geometrical features to study the feasibility of the proposed microforming method and its grain size effect on the formability of the complicated internal features in terms of deformation behavior,material evolution,accuracy of dimensions and final components *** results reveal that the deformation behavior is highly affected by grain size and becomes unpredictable with increased grain *** addition,assembly parameters including feature dimension,tolerance and coaxiality also vary with grain size,and the variation of grain size needs to be accommodated by different assembly types,viz.,clearance fit or transition *** the microstructural evolution aspect,it was identified there were two dead zones and four shear bands,and the formation of these deformation zones was barely affected by the variation in grain *** bulges,cracks,and fracture induced voids were observed on the surface of the final components,tailoring the microstructure of the working material with finer grains could significantly avoid these *** study advances the understanding of forming microparts by extrusion processes and provides guidance for microforming of similar microparts.

关键词： Microformed part Size effect Extrusion Microstructural evolution Dimensions Assembly accuracy

Local field potentials,spiking activity,and receptive fields in human visual cortex

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Science China(Life Sciences) 2024年第3期67卷 543-554页

作者： Lu Luo Xiongfei wang Junshi Lu Guanpeng Chen Guoming Luan Wu Li Qian wang fang fang School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health Peking UniversityBeijing 100871China School of Psychology Beijing Sport UniversityBeijing 100084China Department of Neurosurgery Sanbo Brain HospitalCapital Medical UniversityBeijing 100093China Beijing Key Laboratory of Epilepsy Epilepsy CenterSanbo Brain HospitalCapital Medical UniversityBeijing 100093China IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeijing 100871China Beijing Institute for Brain Disorders Beijing 100069China State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China

The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2/V3). We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–30 Hz) were larger than those estimated from low-gamma activity(LGA, 30–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.

关键词： human visual cortex receptive field intracranial EEG local field potential spiking activity

SO_(2)-Insertion induced enantioselective oxysulfonylation to access β-chiral sulfones with quaternary carbon stereocenters

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Science China Chemistry 2024年第3期67卷 908-913页

作者： Jun Zhang Xuefeng wang Peiqi wang Jiayuan fang Shaoyu Li Jie Wu School of Pharmaceutical and Chemical Engineering&Institute for Advanced Studies Taizhou UniversityShanghai 200438China Department of Chemistry Fudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

β-Chiral sulfones are structural motifs widely found in natural products and bioactive molecules, while also serving as important intermediates for the synthesis of valuable chiral scaffolds. In contrast to the rapid growth of sulfur dioxide insertion chemistry over the last decade, enantioselective catalytic variants for accessing β-chiral sulfones, especially those bearing a quaternary carbon stereocenter, remain rare. Herein, we report an enantioselective copper/bisoxazoline catalyzed oxysulfonylation of alkenes to yield isoxazolinyl-containing β-chiral sulfones bearing quaternary carbon stereocenters with moderate to excellent yields and up to 96:4 er. The advantage and irreplaceability of this sulfur dioxide insertion catalytic system have been demonstrated by achieving transformations clearly unavailable with the previously reported sulfonyl chloride system. Additionally,the recoverability of the new-developed bisoxazoline ligand L9 and its reusability without any erosion of the catalytic activity and enantioselectivity further demonstrate the usefulness of the protocol.

关键词： β-chiral sulfones sulfur dioxide insertion oxysulfonylation copper catalysis enantioselectivity