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Improving photochemical indicators for attributing ozone sensitivities in source apportionment analysis

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Journal of Environmental Sciences 2024年第9期143卷 235-246页

作者： Xiaohui Du Wei Tang zhongzhi Zhang Yang Yu Yang Li Ling Huang Greg Yarwood Fan Meng Atmospheric Environment Institute Chinese Research Academy of Environmental SciencesBeijing 100012China College of Water Sciences Beijing Normal UniversityBeijing 100857China Asia Center for Air Pollution Research United Nations Environment Programme Asia and the Pacific OfficeNishi-kuNiigata-shi 9502144Japan School of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China Ramboll NovatoCalifornia 94945USA

Comprehensive Air Quality Model with extensions(CAMx)-Decoupled Direct Method(DDM)simulations of first-order ozone(O_(3))sensitivity to nitrogen oxides(NO_(x))and volatile organic compounds(VOCs)emissions were performed and combined with modelled P_(H_(2)O_(2))/P_(HNO_(3))ratios to obtain a range of thresholds for determining O_(3)-sensitivity regimes for different areas of *** the new threshold ranges for photochemical indicators,the method for determining O_(3)formation in the Ozone Source Apportionment Technology(OSAT)module within CAMx was improved by a dynamically varied threshold of P_(H_(2)O_(2))/P_(HNO_(3))*** O_(3)concentration contributions in the newly added transition regime were apportioned to NO_(x)and VOCs emissions in proportion to the relationship between the P_(H_(2)O_(2))/P_(HNO_(3))ratio and first-order O_(3)*** source contributions of O_(3)concentrations from different emission sectors from June to September 2019 were compared using the original and improved *** results showed that the O_(3)concentration contributions changed significantly in the NO_(x)-limited regime,with a maximum decrease of 21.89%,while the contributions increased by up to 7.57%in the VOC-limited regime,and were within 15μg/m^(3)in the transition *** modified OSAT module enabled a more sophisticated attribution of O_(3)to precursor emissions and may have far-reaching implications for informing O_(3)pollution control policy.

关键词： O_(3) modeling O_(3)-sensitivity regimes Ozone source apportionment technology Photochemical indicators

Formation processes and source contributions of ground-level ozone in urban and suburban Beijing using the WRF-CMAQ modelling system

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Journal of Environmental Sciences 2023年第5期127卷 753-766页

作者： Shuxian Zhang zhongzhi Zhang Yang Li Xiaohui Du Linglu Qu Wei Tang Jun Xu Fan Meng Research Institute of Atmospheric Environment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Water Sciences Beijing Normal UniversityBeijing 100875China Asia Center for Air Pollution Research Niigata 950-2144Japan

Beijing faces the challenge of high levels of ozone(O_(3))*** this study,the Weather Research and Forecasting model and Community Multiscale Air Qualitymodel(CMAQ)were used to simulate atmospheric O_(3) concentrations in *** investigate the formation mechanisms and source contributions of O_(3) pollution in different regions of Beijing,process analysis and the integrated source apportionmentmethodwithin the CMAQwere applied to O_(3) concentrations in the summer of *** process analysis results showed that vertical diffusion was the major contributor to O_(3) concentrations at all receptor sites in Beijing,at>65.94μg/(m^(3)·hr).Gas-phase chemical reactions consumed a significant amount of O_(3) in urban and inner suburban areas(>−5.57μg/(m^(3)·hr)),while near-surface chemical reactions made positive contributions in outer suburban areas(>4.72μg/(m^(3)·hr)).The O_(3) formation chemical reactions indicated that NO titration,which removes O_(3) at night-time,mainly occurred in urban *** weaker chemical reactions occurring near the surface in outer suburbs suggested that suburban-area O_(3) was produced in the upper atmospheric layers and was transported vertically to the lower *** O_(3) source apportionment results showed that boundary contributions were the dominant contributor to O_(3) pollution in Beijing(>40%).The contribution of non-local emissions to O_(3) levels was significantly greater in the outer suburbs than in urban and inner suburban areas due to *** study increases the understanding of the complex processes of O_(3) formation in different areas of Beijing and informs the implementation of O_(3) control plans.

关键词： Ozone Source apportionment Process analysis Air quality model

Genome-wide pan-GPCR cell libraries accelerate drug discovery

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Acta Pharmaceutica Sinica B 2024年第10期14卷 4296-4311页

作者： Hanting Yang Yongfu Wang Wei Liu Taiping He Jiayu Liao zhongzhi Qian Jinghao zhao zhaotong Cong Dan Sun Zhixiang Liu Can Wang Lingping Zhu Shilin Chen School of Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137China Institute of Herbgenomics Chengdu University of Traditional Chinese MedicineChengdu 611137China School of Basic Medical Science Chengdu University of Traditional Chinese MedicineChengdu 611137China Department of Bioengineering University of CaliforniaRiversideCA 92521USA The Huaxi-Cal Research Center for Predictive Intervention Medicine West China HospitalSichuan UniversityChengdu 610041China Chinese Pharmacopoeia Commission Beijing 100061China

G protein-coupled receptors(GPCRs)are pivotal in mediating diverse physiological and pathological processes,rendering them promising targets for drug *** account for about 40%of FDA-approved drugs,representing the most successful drug ***,only approximately 15%of the 800 human GPCRs are targeted by market drugs,leaving numerous opportunities for drug discovery among the remaining *** expression systems play crucial roles in the GPCR drug discovery field,including novel target identification,structural and functional characterization,potential ligand screening,signal pathway elucidation,and drug safety ***,we discuss the principles,applications,and limitations of widely used cell expression systems in GPCR-targeted drug discovery,GPCR function investigation,signal pathway characterization,and pharmacological property *** also propose three strategies for constructing genome-wide pan-GPCR cell libraries,which will provide a powerful platform for GPCR ligand screening,and facilitate the study of GPCR mechanisms and drug safety evaluation,ultimately accelerating the process of GPCR-targeted drug discovery.

关键词： G-protein coupled receptors Genome-wide pan-GPCR Transgenic cell library High-throughput screening Drug discovery

Characteristics and chemical reactivity of biogenic volatile organic compounds from dominant forest species in the Jing-Jin-Ji area,China

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Forest Ecosystems 2021年第4期8卷 699-712页

作者： Ying Lin Xiaoxiu Lun Wei Tang zhongzhi Zhang Xiaoxi Jing Chong Fan Qiang Wang College of Environmental Science and Engineering Beijing Forestry University100083 BeijingChina Institute of Atmospheric Environment Chinese Research Academy of Environmental Sciences100012 BeijingChina

Background:Biogenic volatile organic compounds(BVOCs)play an essential role in tropospheric atmospheric chemical *** are few studies conducted on BVOCs emission of dominant forest species in the Jing-Jin-Ji area of *** on the field survey,forest resources data and the measured standard emission factors,the Guenther model developed in 1993(G93)was applied in this paper to estimate the emission of BVOCs from several dominant forest species(Platycladus orientalis,Quercus variabilis,Betula platyphylla,Populus tomentosa,Pinus tabuliformis,Robinia pseudoacacia,Ulmus pumila,Salix babylonica and Larix gmelinii)in the Jing-Jin-Ji area in *** the spatiotemporal emission characteristics and atmospheric chemical reactivity of these species were extensively ***:The results showed that the total annual BVOCs emission was estimated to be 70.8 Gg C·year^(−1),consisting 40.5%(28.7 Gg C·year^(−1))of isoprene,36.0%(25.5 Gg C·year^(−1))of monoterpenes and 23.4%(16.6 Gg C·year^(−1))of other *** emissions from Platycladus orientalis,Quercus variabilis,Populus tomentosa and Pinus tabulaeformis contributed 56.1%,41.2%,36.0% and 31.1%,*** total BVOCs emission from the Jing-Jin-Ji area accounted for 61.9% and 1.8%in summer and winter,*** to 28.8% of emission was detected from Chengde followed by Beijing with 24.9%,that mainly distributed in the Taihang Mountains and the Yanshan ***,the Robinia pseudoacacia,Populus tomentosa,Quercus variabilis,and Pinus tabulaeformis contributed mainly to BVOCs reaction ***:The BVOCs emission peaked in summer(June,July,and August)and bottomed out in winter(December,January,and February).Chengde contributed the most,followed by *** orientalis,Quercus variabilis,Populus tomentosa,Pinus tabulaeformis and Robinia pseudoacacia represent the primary contributors to BVOCs emission and atmospheric reactivity,hence the planting of these species sho

关键词： Biogenic volatile organic compounds(BVOCs) Isoprene Monoterpenes Jing-Jin-Ji area Spatiotemporal characteristics Chemical reactivity

Application of the ABEEM/MM model in studying the properties of the water clusters(H_2O)_n(n=7-10)

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Science China Chemistry 2007年第2期50卷 190-204页

作者： QIAN Ping & YANG zhongzhi Faculty of Chemistry and Chemical Engineering,Liaoning Normal University,Dalian 116029,China Faculty of Chemistry and Chemical Engineering Liaoning Normal University Dalian China

ABEEM/MM model has been applied to compute the various properties characterizing water clusters(H2O) n(n = 7-10) ,such as optimized geometries,the hydrogen bonds number,cluster interaction en-ergies,stabilities,ABEEM charge distributions,dipole moments,structural parameters,and so on,and to describe the transition reflected by the hexamer region from two-dimensional(from dimer to pen-tamer) to three-dimensional structures(for clusters larger than the hexamer) .

关键词： ABEEM/MM model the atom-bond electronegativity equalization method molecular mechanics water clusters

计算机RENAL程序测定S/L及食道通过时间

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核电子学与探测技术 1987年第1期 44-47页

作者：朱国泓黄玉琴戴希真葛炳生王忠植赵宝经马步成颜珏李晓鸣荣迅祝凯中日友好医院

RENAL程序是专用于γ照相机的电子计算机普遍采用的程序。主要是用它作肾图,将左、右肾作动态显象,在综合影象上框以感兴趣区(ROI),计算并显示左、右肾各自的四个指标:最大计数(MAXCT),半计数(0.5CT),峰时(TMAX)及注射后最大计数下降一... 详细信息

RENAL程序是专用于γ照相机的电子计算机普遍采用的程序。主要是用它作肾图,将左、右肾作动态显象,在综合影象上框以感兴趣区(ROI),计算并显示左、右肾各自的四个指标:最大计数(MAXCT),半计数(0.5CT),峰时(TMAX)及注射后最大计数下降一半时间门(T(1/2))。最后呈两肾各自的时间-强度曲线,及在同一坐标上的两条曲线。如分别在肝、脾上框以ROI来代替双肾,运用RENAL程序,则便获得肝、脾摄取曲线,计算出牌肝集积比(S/L)。我们在108位正常人和肝病、血液病患者中用此

关键词：肾图程序脾肝集积比食道通过时间时间-强度曲线

GAUSSIAN PIVOTING METHOD FOR SOLVING LINEAR COMPLEMENTARITY PROBLEM

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Applied Mathematics:A Journal of Chinese Universities 1997年第4期 47-54页

作者： LI DONGHUI,ZENG JINPING AND ZHANG zhongzhi

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Reversible folding/unfolding of small α-helix in explicit solvent investigated by ABEEMσπ/MM

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Science China Chemistry 2009年第11期52卷 1917-1924页

作者： LIU Cui & YANG zhongzhi Chemistry and Chemical Engineering Faculty,Liaoning Normal University,Dalian 116029,China Chemistry and Chemical Engineering Faculty Liaoning Normal University Dalian China

We have performed molecular dynamics simulations on the reversible folding/unfolding of small α-helix(short Ala based peptide Ala5) in explicit water solvent in terms of ABEEMσπ/MM.A dynamics analysis shows that the α-helical turn can be preserved up to a period of about 2 ns at 300 K,which supports the conclusions of Margulis et *** time trajectory of the root mean square deviation between the heavy atoms of the backbone and the helical reference structure indicate that "helix melting and formation occurs rapidly on a time scale of 0.1 ns at 300 K" is not a felicitous *** first quantificationally concluded that the helix nucleation can maintain 2 ns,1―1.5 ns and 0.8 ns for Ala5 at 300 K,400 K and 500 K,***,increasing temperature dose not alter the pathway of folding/unfolding,but change the *** analysis of structures in a "transition-state ensemble" shows that helix-to-coil transitions occurs predominantly through breaking of hydrogen bonds at the helix ends(92%),particularly at the C-terminus(50%).Hydrogen bonds' breaking and formation occurs on a time scale of 0.1 ns.

关键词： reversible folding/unfolding of protein Ala5 temperature hydrogen bond

Phytoremediation of petroleum polluted soil

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Petroleum Science 2008年第2期5卷 167-171页

作者： Wang Jing Zhang zhongzhi Su Youming He Wei He Feng Song Hongguang School of Chemical Science ＆ Engineering China University of Petroleum Beijing 102249 China

An experimental study of the rhizosphere effect on phytoremediation of petroleum polluted soil was carried out with three species of grasses, namely Pannicum, Eleusine indica （L.） Gaerth, and Tall Fescue. After a period of 150 days, this pot experiment showed that the rhizosphere of these three species accelerated the degradation of petroleum hydrocarbons to different extents. The results showed that the number of microorganisms in the rhizosphere increased by three orders of magnitude. The induction of the plant rhizosphere and the coercion influence of petroleum changed the species and activity of microorganisms. The degradation of petroleum hydrocarbons in the rhizosphere was 3-4 times that in unplanted soil. The dehydrogenase activity in the rhizosphere was 1.61-2.20 times that in unplanted soil, but the catalase activity was 0.90-0.93 times that in unplanted soil, and soil moisture content increased by 5% compared with the unplanted soil.

关键词： Phytoremediation rhizosphere microbial number dehydrogenase activity catalaseactivity petroleum hydrocarbon degeneration