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Asian Pacific Journal of Tropical Medicine 2011年第6期4卷 475-477页

作者： Ohadoma SC michael hu Department of Pharmacology and Toxicology Madonna UniversityElele Rivers StateNigeria

Objective:To investigate the interacting effects of co-administration of methanol leaf extract of Catharanthus roseus（***） on the hypoglycemic activity of metformin as well as glibenclamide using experimental ***:Phytochemical analysis as well as acute toxicity and lethality(LD50) test were carried out on its methanol leaf *** alloxan model for experimental induction of diabetes in rats was *** groups comprising five rats each were ***Ⅱ,ⅢandⅣreceived 250 mg/kg of extract,100 mg/kg of metformin and 1 mg/kg of glibenclamide respectively,while V and VI were administered metformin-extract and glibenclamide-extract combinations respectively at doses as *** I served as negative control and received only distilled *** administration was done once daily for seven days. Fasting blood glucose was determined at 2,12,24,72 and 168 h using a ***-way ANOVA with post-hoc tests was used to assess for significant difference due to administration of drug alone and with co-administration of drug and ***:The LD50 was 2 121.32 mg/kg. The phytochemical studies indicated the presence of saponins,tannins,alkaloids,phlotatannins, flavonoids,triterpenoids,reducing sugars,anthraquinones and *** medicaments significantly reduced blood glucose levels when compared with control alone（P<0.05） with the highest percentage reduction in blood glucose（64.86%） exhibited by metformin-extract ***:The leaf extract of *** significandy increases the hypoglycemic effect of metformin.

关键词： Catharanthus roseus Hypoglycemic activity Metformin Glibenclamide Co-administration

CD4^＋ T-cell dependence of primary CD8^＋ T-cell response against vaccinia virus depends upon route of infection and viral dose

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Cellular & Molecular Immunology 2016年第1期13卷 82-93页

作者： Zhuting hu michael J Molloy Edward J Usherwood _Department of Microbiology and Immunology Geisel School of Medicine at Dartmouth Lebanon NH USA

CD4^＋ T-cell help （CD4 help） plays a pivotal role in CD8^＋ T-cell responses against viral infections. However, the role in primary CD8^＋ T-cell responses remains controversial. We evaluated the effects of infection route and viral dose on primary CD8^＋ T-cell responses to vaccinia virus （VACV） in MHC class II^-/- mice. CD4 help deficiency diminished the generation of VACV-specific CD8^＋ T cells after intraperitoneal （i.p.） but not after intranasal （i.n.） infection. A large viral dose could not restore normal expansion of VACV-specific CD8^＋ T cells in i.p. infected MHC II-/- mice. In contrast, dependence on CD4 help was observed in i.n. infected MHC II-/- mice when a small viral dose was used. These data suggested that primary CD8~ T-cell responses are less dependent on CD4 help in i.n. infection compared to i.p. infection. Activated CD8~ T cells produced more I FN-y, TNF-a and granzyme B in i.n. infected mice than those in i.p. infected mice, regardless of CD4 help. IL-2 signaling via CD25 was not necessary to drive expansion of VACV-specific CD8~ T cells in i.n. infection, but it was crucial in i.p. infection. VACV-specific CD8^＋ T cells underwent increased apoptosis in the absence of CD4 help, but proliferated normally and had cytotoxic potential, regardless of infection route. Our results indicate that route of infection and viral dose are two determinants for CD4 help dependence, and intranasal infection induces more potent effector CD8^＋ T cells than i.D. infection.

关键词： CD4 help MHC II^-/- mice primary CD8^+ T-cell response vaccinia virus

核-壳结构CdSe/ZnS量子点的制备、硫醇修饰及其光学性能

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中国科学：化学 2010年第10期40卷 1496-1502页

作者：朱华平廖世军 hu michael 邵磊 YU Kui 华南理工大学化学化工学院广州510641 Oak Ridge National Laboratory Oak Ridge Tennessee 37831-6181 USA 纳米材料先进制备技术与应用科学教育部重点实验室北京化工大学北京100029 Steacie Institute for Molecular Sciences National Research Council of Canada Ottawa Ontario KIA 0R6 Canada

采用高温有机相包覆技术制备了CdSe/ZnS核壳结构量子点材料,考察了包覆量对量子点材料的光学性能的影响,研究了含脂肪链和芳香基的双硫醇分子1,4-苯二甲硫醇和1,8-辛二硫醇对于具有核-壳结构的CdSe/ZnS量子点材料的修饰作用,考察了修饰... 详细信息

采用高温有机相包覆技术制备了CdSe/ZnS核壳结构量子点材料,考察了包覆量对量子点材料的光学性能的影响,研究了含脂肪链和芳香基的双硫醇分子1,4-苯二甲硫醇和1,8-辛二硫醇对于具有核-壳结构的CdSe/ZnS量子点材料的修饰作用,考察了修饰作用对于量子点的量子效率和荧光强度等光学性能的影响.实验结果表明:随着硫化锌包覆量的增加,量子点的量子效率及其荧光发射强度明显提高;硫醇的修饰能显著增强量子点的发光强度,随着硫醇浓度的增加,其发光性能增强,但是达到一定程度后,光学性能基本不随硫醇浓度的变化而变化.根据固体核磁共振等实验结果推测:硫醇分子可能部分替代了量子点体系中的正三辛基氧膦配体,稳定了量子点体系,对量子点起修饰保护作用,从而提高了量子点的光学性能.

关键词：核-壳结构量子点量子效率修饰

认清四个现实,绘制人工智能与企业自动化实施路线图

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科技中国 2018年第11期 20-24页

作者： michael hu 李健科尔尼全球

利用机器学习能力,来改善并自动化业务流程,人工智能将在不远的未来释放出巨大的潜力。人工智能(AI)和机器学习开始迅速地被消费者所接受,并在日常生活中随处可见。仅在过去3年里,亚马逊就售出了1000万台Echo智能音箱,而苹果新推出的iPh... 详细信息

利用机器学习能力,来改善并自动化业务流程,人工智能将在不远的未来释放出巨大的潜力。人工智能(AI)和机器学习开始迅速地被消费者所接受,并在日常生活中随处可见。仅在过去3年里,亚马逊就售出了1000万台Echo智能音箱,而苹果新推出的iPhoneX也自带一款人工智能芯片,专门用于处理面部识别和语音命令等任务。然而,AI在自动化和改善业务流程的商务应用方面并没有那么普遍。尽管牛津大学的一项研究表明,人工智能可以在未来20年内使一半以上的工作岗位自动化,但可能是经历了太多媒体过度炒作和不实信息,许多企业高管对这种新兴技术的潜在影响力仍表示怀疑。

关键词：企业自动化人工智能路线图业务流程机器学习学习能力 Echo 智能芯片

复合钙钛矿太阳能电池电荷传输层材料研究进展

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材料导报 2015年第5期29卷 1-7页

作者：陈建清杨东辉江静华马爱斌宋丹 Chaoying Ni michael Z hu 河海大学力学与材料学院南京210098 Department of Materials Science and Engineering University of DelawareNewarkDE 19716 Oak Ridge National Laboratory Oak RidgeTennessee 37831-6181

有机无机复合钙钛矿太阳能电池因具有适合的载流子扩散长度而成为备受关注的有望获得高效率的光伏器件。复合钙钛矿材料本身不含贵金属元素,可以采用液相法或物理气相法低温制备,成本低廉,但目前应用最多的电子传输层材料TiO2需400~500... 详细信息

有机无机复合钙钛矿太阳能电池因具有适合的载流子扩散长度而成为备受关注的有望获得高效率的光伏器件。复合钙钛矿材料本身不含贵金属元素,可以采用液相法或物理气相法低温制备,成本低廉,但目前应用最多的电子传输层材料TiO2需400~500℃煅烧,与柔性基底及低温制备技术适应性差;空穴传输层材料SpiroOMeTAD合成工艺复杂,价格高昂,限制了复合钙钛矿太阳能电池的开发应用。开发和研究导电性好、成本低、稳定性好的电子和空穴传输层材料是复合钙钛矿太阳能电池研究中的一个非常重要的方面。综述了复合钙钛矿太阳能电池中电荷传输层材料的研究进展及发展方向。电子传输层材料方面通过对TiO2的改性以及与石墨烯的复合,采用ZnO、石墨烯或PCBM作为电子传输层材料,以与柔性基底及低温制备技术相适应。空穴传输层材料方面,采用其它低成本、导电性高的有机p型半导体替代spiro-OMeTAD;采用无机空穴传输层材料以避免有机空穴传输层材料的老化问题,提高电池的长期稳定性;利用复合钙钛矿材料兼作吸收层与空穴传输层,制备无空穴传输层材料结构电池以降低成本,提高稳定性。

关键词：有机无机复合钙钛矿太阳能电池光电转换效率电子传输层材料(ETM) 空穴传输层材料(HTM)

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并购关键:复杂性管理

董事会 2010年第10期 56-57页

作者： Joachim Ebert Olivier Aries michael hu 科尔尼

并购是企业增强竞争力颇为有效的一种方式。比如，先灵葆雅收购了荷兰的欧加农，以提高其在大分子产品上的研发能力，并丰富了产品线；伯灵顿北方铁路与圣达菲太平洋的合并则实现了基于规模的运营效率。但是，大量研究表明，通过并购来... 详细信息

并购是企业增强竞争力颇为有效的一种方式。比如，先灵葆雅收购了荷兰的欧加农，以提高其在大分子产品上的研发能力，并丰富了产品线；伯灵顿北方铁路与圣达菲太平洋的合并则实现了基于规模的运营效率。但是，大量研究表明，通过并购来实现股东价值可持续性增长的可能性只有50％。我们认为造成该问题非常关键但又经常被忽略的一个原因是：产品复杂性的增加，也就是两家公司合并了他们的产品、服务，

关键词：复杂性管理并购公司合并产品复杂性产品线研发能力运营效率可持续性

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)

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng Song Ihar Razanau Juanxiu Xiao Wei Xiao Di hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Methane Electrochemical conversion Reaction mechanism Catalyst design Electrode Electrocatalysis

A Novel Model for Describing Rail Weld Irregularities and Predicting Wheel-Rail Forces Using a Machine Learning Approach

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 555-577页

作者： Linlin Sun Zihui Wang Shukun Cui Ziquan Yan Weiping hu Qingchun Meng State Key Laboratory of High-Speed Railway Track System China Academy of Railway Sciences Corporation LimitedBeijing100081China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed *** can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and *** researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry ***,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric *** this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to *** vertical dynamic forces in the time and frequency domains were compared under different running *** forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed ***,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is *** results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the *** ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.

关键词： Rail weld irregularity high-speed railway vehicle-track coupled dynamics wheel/rail dynamic vertical force artificial neural networks

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