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Chinese Chemical Letters 2009年第12期20卷 1498-1501页

作者： zhen zhen hu ying ying Zhong Yun Chang Fan Yan Zhu Department of Chemistry Xixi Campus Zhejiang University Hangzhou 310028 China

In this work, a novel hollow fiber membrane extractor was set up to extract inorganic anions from ethyl acetate using deionized water. Inorganic anions in slightly soluble organic solvents can be determined by the in-line hollow fiber membrane extractor coupled with ion chromatography at first time. Different aspects of the extraction procedure such as magnetic stirring speed, extraction flow rate and extraction time were optimized to achieve high extraction efficiency and good separation results. Satisfactory linear range, limits of detection and good repeatability were obtained. The procedure was applied to analyze inorganic anions in two commercial ethyl acetate samples.

关键词： Inorganic anions Ethyl acetate In-line hollow fiber membrane extraction Ion chromatography

First-principles study on stability, electronic, and mechanical properties of La-C and Ce-C binary compounds

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Journal of Iron and Steel Research International 2019年第7期26卷 771-778页

作者： hui-ning Zhang Qiu-yan Wu zhen-ying hu hui Li hui-hui Xiong An-jun Xu School of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 Jiangxi China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and Technology Wuhan 430081 Hubei China hubei Provincial Key Laboratory for New Processes of Iron making and Steelmaking Wuhan University of Science and Technology Wuhan 430081 Hubei China Ganhua Security Technology Co. Ltd. Nanchang 330001 Jiangxi China China Metallurgical Planning Net Beijing 100711 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The phase stability and electronic and mechanical properties of rare earth (RE) carbides (La2C3, LaC2, Ce2C3, CeC2, and CeC) were investigated using first-principles calculations based on density functional theory. The calculated equilibrium lattice constants and cell volume agree well with available experimental data. The cohesive energy and formation enthalpy of these carbides show that they are thermodynamically and mechanically stable except LaC. The strong covalent bonding exists in these compounds, and the covalent bonds are mainly determined to be RE-C and C-C bonds. The hardness of RExCy compounds is less than 10 GPa, and the bulk modulus, shear modulus, and Young's modulus of Ce2C3 are the largest. The values of BIG (ratio of bulk modulus to shear modulus) and Poisson's ratio indicate that all the compounds have good ductility, and the ductility of CeC is larger than others. The Debye temperature of Ce2C3 is 429.67 K, which is the highest in those of experimental compounds.

关键词： Rare earth carbide Electronic structure Mechanical property First principle

Effects of CpG-ODN on gene expression in formation of foam cells

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Acta Pharmacologica Sinica 2005年第11期26卷 1359-1364页

作者： Kai LI, Bin WAN, zhen-lin hu, ying HE, Xiao-wen HE, Lei JIANG, Shu-han SUN~2 Department of Medical Genetics, College of Basic Medical Sciences, the Second Military Medical University, Shanghai 200433, China Department of Medical Genetics College of Basic Medical Sciences the Second Military Medical University Shanghai China

Aim: To investigate the effects of CpG-oligodeoxynucleotide (CpG-ODN) on the formation of macrophage foam cells and related gene expression. Methods: A gene expression profile was examined by microarray techniques, and mRNA expression was detected by reverse transcriptase polymerase chain reaction (RT-PCR). The cholesterol and cholesteryl ester contents of cells were determined by high performance liquid chromatography. Results: CD36, LPL, and Fcγ2b, which were related to lipid metabolism and the formation of macrophage foam cells, were upregulated after CpG-ODN stimulation. The mRNA expression related to the formation of foam cells was confirmed by semiquantitative RT-PCR. Moreover, histochemical analysis confirmed that lipid deposits inside cells increased after CpG-ODN treatment. However, using flow cytometry, we found that CpG-ODN had no effect on the expression of membrane receptors. Conclusion: CpG-ODN up-regulated the expression of genes in macrophage foam cell formation.

关键词： CpG islands oligodeoxyribonucleotides foam cells macrophages LDL lipoprotein gene expression cholesterol CD 36 antigens lipoprotein lipase Fc gamma receptor Ⅱb

基于EMD和小波分析的实测强风非平稳特性研究

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公路 2017年第8期62卷 81-88页

作者：张威振胡迎新湖南中大设计院有限公司长沙市410075

基于某公路大跨度三塔斜拉桥风环境监测系统,运用经验模态分解(EMD)与小波分析(WT)对实测强风数据样本进行了非平稳分析,分别建立了基于EMD分解和db10小波的非平稳风速模型,并与传统平稳风速模型的计算结果进行比对。研究表明,统计时段... 详细信息

基于某公路大跨度三塔斜拉桥风环境监测系统,运用经验模态分解(EMD)与小波分析(WT)对实测强风数据样本进行了非平稳分析,分别建立了基于EMD分解和db10小波的非平稳风速模型,并与传统平稳风速模型的计算结果进行比对。研究表明,统计时段内实测强风样本的顺、横风向风速均表现出较强的非平稳特征,且基于EMD及WT的非平稳模型的时变趋势项走势基本一致;采用平稳风模型计算的紊流强度、阵风因子、紊流积分尺度值整体上均大于相应的非平稳风模型;实测紊流强度离散性较低,I_u∶I_v值均小于但接近于规范所规定的推荐值1∶0.88;Kaimal谱在中频段与不同风速模型的功率谱均吻合良好,但在低频段和高频段存在较大差异,且就低频段的顺风向风谱而言,平稳模型更接近于Kaimal谱,而横向风谱计算中,非平稳模型更接近于Kaimal谱。

关键词：公路斜拉桥实测强风样本非平稳风速模型经验模态分解小波分析风特性

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang hui Zuo zhengyang Zhou Feng Ding Yue hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance Li–CO_(2)Batteries in a Wide‑Temperature Range

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Nano-Micro Letters 2025年第1期17卷 160-175页

作者： Tingsong hu Wenyi Lian Kang hu Qiuju Li Xueliang Cui Tengyu Yao Laifa Shen Jiangsu Key Laboratory of Materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction ***,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as *** unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon *** illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 *** at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT *** work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.

关键词： Li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)

Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 240-245页

作者： CHEN Jinyou hu Wei School of Automotive Engineering Hunan Financial&Industrial Vocational-technical CollegeHengyang 421002China College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China

To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is *** of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole *** functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of *** experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and *** the voltage reaches 0.8 V,the bending speed of the actuator tends to be ***,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper.

关键词： conductive polymer polypyrrole mechanical characteristics actuators sensing characteristics

基于图像信息处理的蒜核仁内DNA原位排布及其结构模型的研究

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生物化学与生物物理进展 2004年第5期31卷 432-437页

作者：蔡念胡匡祜陶伟苏万芳李防震胡应雄中国科学院生物物理研究所北京100101 北京大学生命科学院北京100080 中国计算机软件与技术总公司北京100081

真核细胞核仁内的DNA超微结构对于阐述rRNA转录位点有着重要的意义 .虽然已经有许多研究者对此提出了不同的观点 ,但是都是基于直接实验观察的 .应用电子显微镜技术和改进的NAMA UrDNA特异染色方法 ,获得蒜核仁超微结构的图像 ,提出一... 详细信息

真核细胞核仁内的DNA超微结构对于阐述rRNA转录位点有着重要的意义 .虽然已经有许多研究者对此提出了不同的观点 ,但是都是基于直接实验观察的 .应用电子显微镜技术和改进的NAMA UrDNA特异染色方法 ,获得蒜核仁超微结构的图像 ,提出一种新技术定量分析核仁中DNA原位位置 .为此 ,建立多尺度形态梯度算子方法 ,编制HEREN .CELL自动分析软件 ,从而抽取出核仁超微结构的精细轮廓 ,显示出核仁DNA的原位位置 .同时 ,提出了DNA纤丝以“花瓣包迹”模式向中心外方向放射的结构模型 .

关键词：核仁 DNA原位排布数学形态学图像信息处理 “花瓣包迹”模式

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng Wang Qinyi Guo Bin hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

Tumor inflammation-specific self-amplifying fluorescent molecular probes induce an anti-tumor immune response

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Science China Chemistry 2025年第1期68卷 273-287页

作者： Shuguang Yang Lijun hu Hong Xiao Zecong Xiao Xintao Shuai PCFM Lab of Ministry of Education School of Materials Science and Engineering Sun Yat-sen University Department of Ultrasound The Fifth Affiliated Hospital Sun Yat-sen University Department of Medical Ultrasound The Third Affiliated Hospital of Sun Yat-sen University Nanomedicine Research Center The Third Affiliated Hospital of Sun Yat-sen University

Enhancing the concentration of exogenous molecular drugs within the tumor microenvironment through enzyme-catalyzed polymerization presents a novel strategy for cancer therapy. Nonetheless, the optimization of the catalytic efficiency is often impeded by the inefficient expression of enzymes. Herein, we reported a self-amplifying fluorescent molecular probe, Bis-HTPICG, for photodynamic therapy(PDT) and subsequent PDT-induced immunoreaction. The Bis-HTP-ICG probe possesses a noticeable enzyme-catalyzed polymerization facilitated by myeloperoxidase(MPO), a crucial enzyme secreted by neutrophils at inflammation sites. Upon exposure to laser irradiation, Bis-HTP-ICG showed a high PDT efficacy, inducing an acute inflammatory response that stimulates further recruitment of neutrophils and then elevated MPO secretion. The heightened level of MPO enhances the accumulation of the Bis-HTP-ICG via self-polymerization or binding with intratumoral proteins following MPO enzyme catalysis, instigating a self-amplifying chain reaction cycle involving Bis-HTP-ICG, neutrophils and ***, PDT efficiently incites immunogenic cell death(ICD) in tumor cells, initiating an anti-tumor immune response including dendritic cells(DCs) maturation, T cell proliferation and reprogramming of tumor-associated neutrophils(TANs). This work portrays a promising strategy for self-amplification of fluorescent molecular probes through adjustable enzyme levels,potentially offering a unique avenue to enhance the tumor accumulation of molecular drugs for improved tumor therapy.

关键词： fluorescent molecular probes self-amplifying myeloperoxidase photodynamic therapy