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Cosmological evolution of quintessence with a sign-changing interaction in dark sector

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1805-1808页

作者： zhang Ming SUN ChengYi YANG zhanying YUE RuiHong Department of Physics Northwest University Institute of Modern Physics Northwest University Faculty of Science Ningbo University

Dark energy and dark matter are only indirectly measured though their gravitational effects.It is possibie that there is some direct,non-gravitational interaction between DE and DM,which can be used to solve(or,at least alleviate)several important theoretical problems.In the present work,by analysing the cosmological dynamical system with a dark-sector interaction which changes its sign during the cosmological evolution,we find a scaling attractor to help to alleviate the cosmic-coincidence problem.This result shows that this interaction can bring new features to the cosmology.

关键词：引力相互作用宇宙演化引力作用进化过程动力系统暗物质暗能量宇宙观

Framework and development of data-driven physics based model with application in dimensional accuracy prediction in pocket milling

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Chinese Journal of Aeronautics 2021年第6期34卷 162-177页

作者： zhanying CHEN Liping WANG Jiabo zhang Guoqiang GUO Shuailei FU Chao WANG Xuekun LI Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China State Key Lab of Tribology Tsinghua UniversityBeijing 100084China Beijing Spacecrafts China Academy of Space TechnologyBeijing 100094China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

In the manufacturing of thin wall components for aerospace industry,apart from the side wall contour error,the Remaining Bottom Thickness Error(RBTE)for the thin-wall pocket component(e.***.rocket shell)is of the same importance but overlooked in current research.If the RBTE reduces by 30%,the weight reduction of the entire component will reach up to tens of kilograms while improving the dynamic balance performance of the large component.Current RBTE control requires the off-process measurement of limited discrete points on the component bottom to provide the reference value for compensation.This leads to incompleteness in the remaining bottom thickness control and redundant measurement in manufacturing.In this paper,the framework of data-driven physics based model is proposed and developed for the real-time prediction of critical quality for large components,which enables accurate prediction and compensation of RBTE value for the thin wall components.The physics based model considers the primary root cause,in terms of tool deflection and clamping stiffness induced Axial Material Removal Thickness(AMRT)variation,for the RBTE formation.And to incorporate the dynamic and inherent coupling of the complicated manufacturing system,the multi-feature fusion and machine learning algorithm,i.***.kernel Principal Component Analysis(kPCA)and kernel Support Vector Regression(kSVR),are incorporated with the physics based model.Therefore,the proposed data-driven physics based model combines both process mechanism and the system disturbance to achieve better prediction accuracy.The final verification experiment is implemented to validate the effectiveness of the proposed method for dimensional accuracy prediction in pocket milling,and the prediction accuracy of AMRT achieves 0.014 mm and 0.019 mm for straight and corner milling,respectively.

关键词： Data-driven Physics based model Thin-wall component Pocket milling Remaining bottom thickness error

Microfluidic adhesion analysis of single glioma cells for evaluating the effect of drugs

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Science China Chemistry 2020年第6期63卷 865-870页

作者： Qiang zhang Sifeng Mao Weiwei Li Qiushi Huang Shuo Feng zhanying Hong Jin-Ming Lin Department of Chemistry Beijing Key Laboratory of Micronalytical Methods and InstrumentationMOE Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical BiologyTsinghua UniversityBeijing 100084China Department of Pharmaceutical Analysis School of PharmacyShanghai Key Laboratory for Pharmaceutical Metabolites ResearchNaval Medical UniversityShanghai 200433China

Cancer metastasis is one of the most serious problems for tumor therapy,which is closely related to cell adhesion and deadhesion process.Better comprehension of cell adhesion ability will benefit drug research.Here,a biomimetic microfluidic enzyme digestion method was proposed to gently measure the influence of drugs on cell-matrix adhesion ability at the single cell level.The method can selectively digest the extracellular matrix(ECM)that linked to a single cell,and the trypsin concentration around the cell is relatively uniform and constant,thus the measured cell adhesion strength should be precise.Commercially available anti-cancer agents including 5-fluorouracil(5-FU),actinomycin D(Act D),temozolomide(TMZ)and allicin were evaluated,and the data showed only TMZ and allicin can inhibit cell adhesion significantly under our experiment conditions.The influence of TMZ became more and more obvious as the increase of duration and the effect became prominent only after 6 h adhesion process,which could provide a quick evaluation of whether the drugs are effective to cancer cell(compared with Calcein-AM/PI cell viability test).The adhesion strength of U87 cells decreased when the concentration of TMZ increased,and the effect of TMZ can be effectively inhibited by adding lactic acid to culture medium,which indicated acidic tumor microenvironment could promote drug resistance of tumor cells.Different from conventional evaluation methods which focus on the drugs’influence on cellular viability or metabolism,this work provides a new perspective to study the effect of drugs,which is helpful to enrich the drug evaluation system.

关键词： microfluidic single cell analysis cell adhesion drug evaluation

Hydrothermal Synthesis and Visible-light Photocatalytic Activities of SnS_2 Nanoflakes

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Journal of Wuhan University of Technology(Materials Science) 2015年第2期30卷 276-281页

作者：贾铁昆 MIN Zhiyu CAO Jianliang SUN Guang WANG Xiaodong zhang zhanying LI Tingting Department of Materials Science and Engineering Luoyang Institute of Science and Technology School of Materials Science and Engineering Henan Polytechnic University Sinosteel Refractory Co. Ltd.

SnS2 nanoflakes were successfully synthesized via a simple hydrothermal process. The as-prepared SnS2 samples were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, nitrogen adsorption-desorption isotherms, and UV-vis diffuse reflectance spectroscopy（DRS）. The photocatalytic activities of the as-prepared SnS2 nanoflakes under visible light irradiation（λ〉420 nm） were evaluated by the degradation of rhodamine B（Rh B）. The effect of hydrothermal temperatures on the photocatalytic efficiency of as-prepared SnS2 nanoflakes was investigated. The experimental result showed that SnS2 nanoflakes synthesized at the temprature of 160 o had higher photocatalytic efficiency and good photocatalytic stability.

关键词： SnS2 nanoflakes hydrothermal synthesis photocatalytic activities stability

基于第一性原理的Au、Cu、Sb掺杂CdTe的结构模拟和光学性能预测

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人工晶体学报 2023年第8期52卷 1400-1406页

作者：张平威林龙张战营中建材(洛阳)新能源有限公司洛阳471000 河南理工大学材料科学与工程学院焦作454000

基于密度泛函理论研究了Au、Cu、Sb掺杂CdTe体系的电子结构和光学性能。Au、Cu、Sb掺杂CdTe体系均能稳定存在,过渡金属原子与Cd原子轨道的杂化减小了CdTe的带隙,提高了CdTe对可见光的利用,同时降低了光生电子从价带跃迁到导带所需的能量... 详细信息

基于密度泛函理论研究了Au、Cu、Sb掺杂CdTe体系的电子结构和光学性能。Au、Cu、Sb掺杂CdTe体系均能稳定存在,过渡金属原子与Cd原子轨道的杂化减小了CdTe的带隙,提高了CdTe对可见光的利用,同时降低了光生电子从价带跃迁到导带所需的能量,从而促进了更多的光生电子发生迁移,大大提高了其光学性能。三种掺杂体系中Sb/CdTe体系在可见光范围内光吸收系数提升最显著,其光生电子和光生空穴迁移率相对于CdTe体系分别增加5.97倍和15.54倍。通过计算掺杂体系的能带、态密度、电子布居、光吸收函数、载流子迁移率,从理论上揭示了Au、Cu、Sb提高CdTe光学性能的机理。

关键词： CdTe 第一性原理电子性质光学性能载流子迁移

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直流微电网一致性简捷均功控制

电力系统及其自动化学报 2023年第3期35卷 14-20页

作者：仝战营张文常帅兵河南工学院电气工程与自动化学院新乡453003 新乡市起重机电气控制重点实验室新乡453003 武汉大学电气与自动化学院武汉430072

多源均功、电池荷电状态均衡和直流母线电压稳定是直流微电网多源并联控制的3个重要研究问题,相互间存在紧密联系和多重约束。利用稀疏通信在相邻变换器间仅共享电流信息,以局部变量信息观测出全局平均电流和电压,降低通讯量和计算量。... 详细信息

多源均功、电池荷电状态均衡和直流母线电压稳定是直流微电网多源并联控制的3个重要研究问题,相互间存在紧密联系和多重约束。利用稀疏通信在相邻变换器间仅共享电流信息,以局部变量信息观测出全局平均电流和电压,降低通讯量和计算量。将观测均值作为反馈分别增设电流和电压二次调节器,并在下垂环节和电流二次调节中增加荷电状态收敛函数,使负荷电流随着荷电状态的动态均衡而实现合理分配。最后,实验表明该策略在仅通信电流信息情况下实现了直流微电网的荷电状态均衡、功率分配及直流母线电压稳定的三大控制目标。

关键词：直流微电网均功控制一致性算法简捷均功控制

Alarm for TDI Capacity Surplus in 2011

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China Chemical Reporter 2010年第18期21卷 16-17页

作者： zhang Baohui and zhang zhanying,ChemChina Cangzhou Dahua Group ChemChina Cangzhou Dahua Group

China consumes around 25% of the world’stoluene diisocyanate (TDI).TDI is mainlyused in flexible polyurethane (PU) foams,PU elastomers,coatings and adhesives.The application in flexible PU foams is the mostextensive,accounting for more than 80% ofthe total.Coatings come next at around 16.7%.China’s TDI production facilities havebeen constructed on the basis of

关键词： facilities accounting imported polyurethane furnit

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纤维素基生物可降解塑料的研究进展及展望

工程塑料应用 2022年第11期50卷 168-172页

作者：张智超孙占英王鑫河北科技大学材料科学与工程学院石家庄050018 河北省柔性功能材料重点实验室石家庄050018

综述了近些年纤维素基生物降解塑料制备方法的研究进展,所列制备方法包括共混法、化学改性法和NaOH/尿素低温体系制备纤维素塑料的方法。同时介绍了纤维素基生物塑料在降解方面的研究,介绍了不同的降解方式,如生物降解、光降解和光-生... 详细信息

综述了近些年纤维素基生物降解塑料制备方法的研究进展,所列制备方法包括共混法、化学改性法和NaOH/尿素低温体系制备纤维素塑料的方法。同时介绍了纤维素基生物塑料在降解方面的研究,介绍了不同的降解方式,如生物降解、光降解和光-生物降解。并对纤维素基生物塑料在包装、农业及电子等领域的应用展开叙述,最后对纤维素基生物塑料的研究前景进行了展望。

关键词：纤维素可降解生物塑料低碳环保

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不同包装方式对咸干花生储藏品质的影响

中国粮油学报 2023年第10期38卷 15-21页

作者：张喻邱展英许秋桐湖南农业大学食品科学技术学院长沙410128

采用Schaal烘箱法加速氧化实验,分别测定经真空包装、真空脱氧包装、充氮包装和普通包装的咸干花生脂肪酸组成、色差、酸价和过氧化值等指标的变化,同时通过过氧化值来建立动力学模型以预测咸干花生的货架期。结果表明:真空包装、真空... 详细信息

采用Schaal烘箱法加速氧化实验,分别测定经真空包装、真空脱氧包装、充氮包装和普通包装的咸干花生脂肪酸组成、色差、酸价和过氧化值等指标的变化,同时通过过氧化值来建立动力学模型以预测咸干花生的货架期。结果表明:真空包装、真空脱氧包装和充氮包装处理可有效延缓咸干花生脂肪氧化,抑制酸价和过氧化值的上升幅度。真空脱氧包装组货架期最长,为111 d;真空包装组和充氮包装组货架期分别为100 d和94 d,普通包装组货架期最短,为82 d。因此,真空脱氧包装能有效地保持咸干花生的储藏品质。

关键词：包装方式咸干花生货架期储藏品质