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Chinese Journal of Chemical Physics 2020年第5期33卷 635-641,I0070-I0077,I0079页

作者： Jing Long Zhao Ye yong Du Xu-ming Zheng Jia-dan xue Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China Centre for THz Research China Jiliang UniversityHangzhou 310018China

Photo-induced proton coupled electron transfer(PCET)is essential in the biological,photosynthesis,catalysis and solar energy conversion ***,p-nitrophenylphenol(HO-Bp-NO2)has been used as a model compound to study the photo-induced PCET mechanism by using ultrafast *** transient absorption spectra both singlet and triplet states were observed to exhibit PCET behavior upon laser excitation of *** we focused on the PCET in the triplet state,a new sharp band attracted *** band was recorded upon excitation of HO-Bp-NO2 in aprotic polar solvents,and has not been observed for p-nitrobiphenyl which is without hydroxyl *** order to find out what the new band represents,acidic solutions were used as an additional proton donor considering the acidity of *** the help of results in strong(~10^-1 mol/L)and weak(~10^-4 mol/L)acidic solutions,the new band is identified as open shell singlet O-Bp-NO2H,which is generated through protonation of nitro O in 3HO-Bp-NO2 followed by deprotonation of *** analysis indicates that the formation of radical·OBp-NO2 competes with O-Bp-NO2H in the way of concerted electron-proton transfer and/or proton followed electron transfers and is responsible for the low yield of *** results in the present work will make it clear how the3HO-Bp-NO2 deactivates in aprotic polar solvents and provide a solid benchmark for the deeply studying the PCET mechanism in triplets of analogous aromatic nitro compounds.

关键词： Proton coupled electron transfer Intramolecular charge transfer Transient absorption Triplet nitrophenylphenol

Time-domain hydrodynamic analysis of pontoon-plate floating breakwater

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Water Science and Engineering 2012年第3期5卷 291-303页

作者： Zhi-jie CHEN yong-xue WANG Hua-yang DONG Bin-xin ZHENG Open Laboratory of Ocean & Coast Environmental Geology Third Institute of Oceanography State Oceanic Administration Xiamen 361005 P. R. China Hunan Province Key Laboratory of Water Sediment Science & Flood Hazard Prevention Changsha University of Science & Technology Changsha 410004 P R. China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 P. R. China Development and Construction Corporation of Dalian Jinzhou Economic Development Zone Dalian 116100 P. R. China

The hydrodynamic behaviors of a floating breakwater consisting of a rectangular pontoon and horizontal plates are studied theoretically. The fluid motion is idealized as two-dimensional linear potential flow. The motions of the floating breakwater are assumed to be two-dimensional in sway, heave, and roll. The solution to the fluid motion is derived by transforming the governing differential equation into the integral equation on the boundary in time domain with the Green＇s function method. The motion equations of the floating breakwater are established and solved with the fourth-order Runge-Kutta method to obtain the displacement and velocity of the breakwater. The mooring forces are computed with the static method. The computational results of the wave transmission coefficient, the motion responses, and the mooring forces of the pontoon-plate floating breakwater are given. It is indicated that the relative width of the pontoon is an important factor influencing the wave transmission coefficient of the floating breakwater. The transmission coefficient decreases obviously as the relative width of the pontoon increases. The horizontal plates help to reduce the wave transmission over the floating breakwater. The motion responses and the mooring forces of the pontoon-plate floating breakwater are less than those of the pontoon floating breakwater. The mooring force at the offshore side is larger than that at the onshore side.

关键词： hydrodynamic analysis, pontoon-plate floating breakwater transmission coefficient,"motion response," mooring force

Digital image processing of saturation for two-phase flow in planar porous media model

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Water Science and Engineering 2012年第2期5卷 202-209页

作者： Zhi DOU Zhi-fang ZHOU Si WANG yong huang School of Earth Sciences and Engineering Hohai UniversityNanjing 210098R R.China

In this paper, the accuracy of estimating stained non-wetting phase saturation using digital image processing is examined, and a novel post-processing approach for calculating threshold is presented. In order to remove the effect of the background noise of images and to enhance the high-frequency component of the original image, image smoothing and image sharpening methods are introduced. Depending on the correct threshold, the image binarization processing is particularly useful for estimating stained non-wetting phase saturation. Calculated saturation data are compared with the measured saturation data during the two-phase flow experiment in an artificial steel planar porous media model. The results show that the calculated saturation data agree with the measured ones. With the help of an artificial steel planar porous media model, digital image processing is an accurate and simple method for obtaining the stained non-wetting phase saturation.

关键词： digital image processing " saturation " two-phase flow " planar porous media model

High efficiency and enhanced ESD properties of UV LEDs by inserting p-GaN/p-AlGaN superlattice

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Science China(Physics,Mechanics & Astronomy) 2014年第5期57卷 887-891页

作者： huang yong LI PeiXian YANG Zhuo HAO Yue WANG XiaoBo State Key Discipline Laboratory of Wide Bandgap Semiconductor Technology Xidian University Zoomview Optoelelectronic Co. Ltd.

Significantly improved electrostatic discharge （ESD） properties of InGaN/GaN-based UV light-emitting diode （LED） with in- serting p-GaN/p-A1GaN superlattice （p-SLs） layers （instead of p-A1GaN single layer） between multiple quantum wells and Mg-doped GaN layer are reported. The pass yield of the LEDs increased from 73.53% to 93.81% under negative 2000 V ESD pulses. In addition, the light output power （LOP） and efficiency droop at high injection current were also improved. The mechanism of the enhanced ESD properties was then investigated. After excluding the effect of capacitance modulation, high-resolution X-ray diffraction （XRD） and atomic force microscope （AFM） measurements demonstrated that the dominant mechanism of the enhanced ESD properties is the material quality improved by p-SLs, which indicated less leakage paths, ra- ther than the current spreading improved by p-SLs.

关键词： GaN LED superlattice ESD

High throughput relay policy in wireless cooperative relaying networks based on stochastic control theory

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 1-6页

作者： LI yong HOU Yi-bin huang Zhang-qin WEI Yi-fei Embedded Software and Systems Institute Beijing University of Technology Beijing 100124 China School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This paper proposes a distributed relay and modulation and coding scheme （MCS） selection in wireless cooperative relaying networks where the adaptive modulation and coding （AMC） scheme is applied. First-order finite-state Markov channels （FSMCs） are used to model the wireless channels and make prediction. The objective of the relay policy is to select one relay and MCS among different alternatives in each time-slot according to their channel state information （CSI） with the goal of maximizing the throughput of the whole transmission period. The procedure of relay and MCS selection can be formulated as a discounted Markov decision chain, and the relay policy can be obtained with recent advances in stochastic control algorithms. Simulation results are presented to show the effectiveness of the proposed scheme.

关键词： relay policy cooperative relaying networks finite-state Markov channel stochastic control

Natural history and cycle threshold values analysis of COVID-19 in Xiamen City,China

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Infectious Disease Modelling 2022年第3期7卷 486-497页

作者： Bin Deng Weikang Liu Zhinan Guo Li Luo Tianlong Yang Jiefeng huang Buasiyamu Abudunaibi Yidun Zhang xue Ouyang Demeng Wang Chenghao Su Tianmu Chen State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamen CityFujian ProvincePeople's Republic of China Xiamen Center for Disease Control and Prevention Xiamen CityFujian ProvincePeople's Republic of China Zhongshan Hospital Fudan University(Xiamen Branch)Xiamen CityFujian ProvincePeople's Republic of China

Objective:This study elaborated the natural history parameters of Delta variant,explored the differences in detection cycle thresholds(Ct)among ***:Natural history parameters were calculated based on the different onset time and exposure time of the *** relationships between generations of cases were *** in Ct values of cases by gender,age,and mode of detection were analyzed statistically to assess the detoxification capacity of ***:The median incubation period was 4 days;the detection time for cases decreased from 25 to 7 h as the outbreak *** average generation time(GT),time interval between transmission generations(TG)and serial interval(SI)were 3.6±2.6 days,1.67±2.11 days and 1.7±3.0 *** the Ct values,we found little differences in testing across companies,but there were some differences in the gender of detected *** Ct values continuous to decreased with age,but increased when the age was greater than ***:This epidemic was started from aggregation of *** is more reasonable to use SI to calculate the effective reproduction number and the time-varying reproduction *** the analysis of Ct values can improve the positive detection rate and improve prevention and control measures.

关键词： COVID-19 Natural history Cycle threshold value

Preparation and Electrochemical Characters of Parathion Molecule Imprinted Polymeric Sensors

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Chemical Research in Chinese Universities 2011年第1期27卷 28-33页

作者： huang yong-xing LIAN Hui-ting SUN Xiang-ying LIU Bin College of Material Science and Engineering Huaqiao University Xiamen 361021 P. R. China

A sensitive, fast and low-cost molecular imprinted polymeric sensor for quantitative determination of parathion was prepared with chitosan（CS） as function matrix and parathion（PT） as template molecule via constant potential electrochemical deposition. Sensitive response was obtained with a detection limit of 1.0× 10-7 mol/L and an excellent recognition for PT was achieved due to the good memory capacity of the sensor. The developed sensor exhibited good fabrication reproducibility and acceptable stability, which provided a new promising tool for pesticide analysis.

关键词： Molecular imprinting polymer Electrochemical sensor Chitosan Parathion

Comparing T-and B-cell responses to COVID-19 vaccines across varied immune backgrounds

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Signal Transduction and Targeted Therapy 2023年第6期8卷 3029-3038页

作者： Zhen Cui Wenxin Luo Ruihong Chen Yalun Li Zhoufeng Wang yong Liu Shuo Liu LeiLei Feng Zijing Jia Ruixin Cheng Jun Tang Weijin huang Yanjun Zhang Huawen Liu Xiangxi Wang Weimin Li CAS Key Laboratory of Infection and Immunity National Laboratory of MacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing100101China Department of Respiratory and Critical Care Medicine Institute of Respiratory HealthPrecision Medicine CenterPrecision Medicine Key Laboratory of Sichuan ProvinceFrontiers Science Center for Disease-related Molecular NetworkWest China HospitalSichuan UniversityChengdu610041China Precision Medicine Center Precision Medicine Key Laboratory of Sichuan ProvinceFrontiers Science Center for Disease-related Molecular NetworkWest China HospitalSichuan UniversityChengdu610041China Department of Neurology Chongqing University Three Gorges HospitalChongqing UniversityChongqingChina Division of HIV/AIDS and Sex-transmitted Virus Vaccines Institute for Biological Product ControlNational Institutes for Food and Drug Control(NIFDC)No.31 Huatuo StreetDaxing DistrictBeijing102629China Department of Microbiology Zhejiang Provincial Center for Disease Control and PreventionHangzhouChina Department of Oncology Chongqing University Three Gorges HospitalChongqing UniversityChongqingChina

The emergence of adapted variants of the SARS-CoV-2 virus has led to a surge in breakthrough infections worldwide.A recent analysis of immune responses in people who received inactivated vaccines has revealed that individuals with no prior infection have limited resistance to Omicron and its sub-lineages,while those with previous infections exhibit a significant amount of neutralizing antibodies and memory B ***,specific T-cell responses remain largely unaffected by the mutations,indicating that T-cell-mediated cellular immunity can still provide ***,the administration of a third dose of vaccine has resulted in a marked increase in the spectrum and duration of neutralizing antibodies and memory B cells in vivo,which has enhanced resistance to emerging variants such as BA.2.75 and *** results highlight the need to consider booster immunization for previously infected individuals and the development of novel vaccination *** rapid spread of adapted variants of the SARS-CoV-2 virus presents a significant challenge to global *** findings from this study underscore the importance of tailoring vaccination strategies based on individual immune backgrounds and the potential need for booster shots to combat emerging *** research and development are crucial to discovering new immunization strategies that will effectively protect public health against the evolving virus.

关键词： vaccines immunity adapted

The withdrawal of the U.S. from the Paris Agreement and its impact on global climate change governance

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Advances in Climate Change Research 2017年第4期8卷 213-219页

作者： ZHANG yong-Xiang CHAO Qing-Chen ZHENG Qiu-Hong huang Lei National Climate Center China Meteorological Administration Beijing 100081 China China Meteorological Administration Training Center Beijing 100081 China

The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused worldwide reaction. Trump will use the withdrawal to build his political reputation and to renegotiate the Paris Agreement despite its negative effects on the political credibility, international relationships, and potential long-term economic growth of the U.S. In general, the withdrawal of the U.S. from the Paris Agreement will not change the development of low-carbon technologies and the transformation trend of the global climate governance regime. However, the long-term goals and international cooperation on climate change will be affected by budget cuts in American climate change research and the cancelation of donations from the multilateral environmental fund of the U.S. If the Paris Agreement is renegotiated, the common but differentiated principle of responsibility of the United Nations Framework Convention on Climate Change will be challenged again. Nevertheless, climate change governance remains a main theme of future sustainable development. Instead of national governments, local governments and non-governmental organizations will develop strategies for technical innovation and emphasize pragmatic cooperation, thus expanding their roles in climate change governance. The capacity building on climate change research and public awareness should be enhanced as a long-term objective of global climate change governance.

关键词： U.S. withdraw Paris Agreement Global climate change governance Impact

Methylprednisolone inhibits activated CD4^+ T cell survival promoted by toll-like receptor ligands

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Hepatobiliary & Pancreatic Diseases International 2010年第4期9卷 376-383页

作者： Lu, You-Sheng Pu, Li-yong Li, Xiang-Cheng Wang, xue-Hao Nanjing Med Univ Affiliated Hosp 1 Liver Transplantat Ctr Peoples Hosp Jiangsu Prov Nanjing 210029 Peoples R China

BACKGROUND: Methylprednisolone (MP) can affect the survival of CD4(+) T lymphocytes and plays an important role in adaptive immune responses; however, its mechanism of action is not clear. Recent studies have shown that toll-like receptors (TLRs) on CD4(+) T cells can directly modulate adaptive immune responses by affecting the survival and proliferation of activated CD4(+) T cells. This study aimed to investigate the relationship between MP, TLRs and activated CD4(+) T cells. METHODS: We separated and purified CD4(+) T cells from mice, activated them in vitro, and co-cultured them with TLR ligands, MP or inhibitors of nuclear factor-kappa B (NF-kappa B) and activator protein 1 (AP-1). We then assessed CD4(+) T cell survival and proliferation and the expression of NF-kappa B and AP-1. RESULTS: Activated CD4(+) T cells showed increased TLR-3 and TLR-9 mRNA expression, but polyinosinic-polycytidylic acid (poly I:C) and MP had no effect on the expression of these mRNAs. Still, poly I:C and CpG oligodeoxynucleotides (CpG DNA) increased the survival of activated CD4(+) T cells, whereas MP reduced the survival of activated CD4(+) T cells and could inhibit the survival effects of poly I:C and CpG DNA. The NF-kappa B essential modifier-binding domain (NBD) inhibited the survival of activated CD4(+) T cells induced by poly I:C and CpG DNA, but the AP-1 inhibitor crucumin did not have the same effect. The increased expression of NF-kappa B induced by poly I:C and CpG DNA in activated CD4(+) T cells could be inhibited by MP, but the same was not true for the increased expression of AP-1 induced by poly I:C and CpG DNA. Finally, the proliferation of activated CD4(+) T cells was not affected by poly I:C or MP. CONCLUSION: The survival of activated CD4(+) T cells is promoted by TLR ligands, but this effect is inhibited by MP.

关键词： methylprednisolone toll-like receptor CD4(+) T lymphocytes NF-kappa B