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水文模式DHSVM与区域气候模式RegCM2/China嵌套模拟试验 被引量:21
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作者 王守荣 黄荣辉 +3 位作者 丁一汇 L.R.Leung M.S.Wigmosta L.W.Vail 《气象学报》 CSCD 北大核心 2002年第4期421-427,共7页
本研究在改进水文 -土壤 -植被模式DHSVM ,用气候观测资料驱动DHSVM进行模拟试验的基础上 ,建立了区域气候模式RegCM2 /China与水文模式DHSVM的嵌套系统 ,将区域气候模式对中国和东亚地区控制试验 (目前气候情景 )和敏感性试验 (未来 2&... 本研究在改进水文 -土壤 -植被模式DHSVM ,用气候观测资料驱动DHSVM进行模拟试验的基础上 ,建立了区域气候模式RegCM2 /China与水文模式DHSVM的嵌套系统 ,将区域气候模式对中国和东亚地区控制试验 (目前气候情景 )和敏感性试验 (未来 2×CO2 气候情景 )结果用双线性插值方法降尺度 (downscaling)到滦河、桑干河流域的 8个气象站点 ,然后再用数字高程模式DEM插值到DHSVM的细网格点 ,驱动水文模式进行嵌套模拟试验。试验结果表明 ,滦河、桑干河流域在未来大气中CO2 浓度加倍情况下 ,地面气温呈一致的增加趋势 ,年平均气温增加2 .8℃ ;两流域未来降水也呈增加趋势 ,滦河、桑干河流域年降水量分别增加 6mm和 4 6mm ;两流域未来蒸发量有所增加 ,年均蒸发量增加 2 9mm ;未来滦河流域年径流深减少 2 7mm ,流量减少 14 .72× 10 8m3 ,桑干河流域径流深增加 2 6mm ,流量增加 12 .2 2× 10 8m3 ,两流域合计 ,流量减少 2 .5× 10 8m3 ;未来滦河、桑干河流域径流深趋向一致 ,分别为 74和 71mm ,约为全国目前平均径流深 2 84mm的 1/ 4。可见 ,两流域未来总体上仍呈现暖干化趋势。本研究发展的嵌套模式系统具有一定的预测能力 ,而且通过参数移植 。 展开更多
关键词 DHSVM regcm2/china 区域气候模式 水文模式 嵌套试验 预测分析 气候变率 气候变化
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Exploring the impact of economic growth and energy consumption on SO_(2) emissions in China based on the Environmental Kuznets Curve hypothesis
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作者 Bing-Jie Xu Yi-Fei Shen +1 位作者 Hui Qiao Zhi Gao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2892-2900,共9页
This study aims to analysis the influence of economic growth(EG)and energy consumption(EC)on sulfur dioxide emissions(SE)in China.Accordingly,this study explores the link between EG,EC,and SE for 30 provinces in China... This study aims to analysis the influence of economic growth(EG)and energy consumption(EC)on sulfur dioxide emissions(SE)in China.Accordingly,this study explores the link between EG,EC,and SE for 30 provinces in China over the span of 2000-2019.This study also analyzes cross-sectional dependence tests,panel unit root tests,Westerlund panel cointegration tests,Dumitrescu-Hurlin(D-H)causality tests.According to the test results,there is an inverted U-shaped association between EG and SE,and the assumption of the Environmental Kuznets Curve(EKC)is verified.The signs of EG and EC in the fixed effect(FE)and random effect(RE)methods are in line with those in the dynamic ordinary least squares(DOLS),fully modified ordinary least squares(FMOLS)and autoregressive distributed lag(ARDL)estimators.Moreover,the results verified that EC can obviously positive impact the SE.To reduce SE in China,government and policymakers can improve air quality by developing cleaner energy sources and improving energy efficiency.This requires the comprehensive use of policies,regulations,economic incentives,and public participation to promote sustainable development. 展开更多
关键词 SO_(2)emissions Economic growth Energy consumption EKC china
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Genetic and biological properties of H9N2 avian influenza viruses isolated in central China from2020 to 2022
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作者 Libin Liang Yaning Bai +14 位作者 Wenyan Huang Pengfei Ren Xing Li Dou Wang Yuhan Yang Zhen Gao Jiao Tang Xingchen Wu Shimin Gao Yanna Guo Mingming Hu Zhiwei Wang Zhongbing Wang Haili Ma Junping Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2778-2791,共14页
The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by se... The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by serving as a"donor virus")infect humans,posing a significant threat to public health.Currently,there is a lack of in-depth research on the prevalence of H9N2 viruses in Shanxi Province,central China.In this study,we isolated 14 H9N2 AIVs from October 2020 to April 2022 in Shanxi Province,and genetic analysis revealed that these viruses belonged to 7 different genotypes.Our study on animals revealed that the H9N2 strains we identified displayed high transmission efficiency among chicken populations,and exhibited diverse replication abilities within these birds.These viruses could replicate efficiently in the lungs of mice,with one strain also demonstrating the capacity to reproduce in organs like the brain and kidneys.At the cellular level,the replication ability of different H9N2 strains was evaluated using plaque formation assays and multi-step growth curve assays,revealing significant differences in the replication and proliferation efficiency of the various H9N2 viruses at the cellular level.The antigenicity analysis suggested that these isolates could be classified into 2 separate antigenic clusters.Our research provides crucial data to help understand the prevalence and biological characteristics of H9N2 AIVs in central China.It also highlights the necessity of enhancing the surveillance of H9N2 AIVs. 展开更多
关键词 avian influenza virus H9N2 central china PATHOGENICITY ANTIGENICITY
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Temporal Variability of Tropospheric NO_(2)over Cities in the United States,Western Europe and China from 2005 to 2022
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作者 ZHANG Qianqian 《Chinese Geographical Science》 SCIE CSCD 2024年第6期983-992,共10页
Anthropogenic Nitrogen oxides(NO_(x)=NO_(2)+NO)emissions are highly concentrated in urban area,and the weekly cycles,seasonal patterns and long-term trends of tropospheric NO_(2)columns over cities differ from region ... Anthropogenic Nitrogen oxides(NO_(x)=NO_(2)+NO)emissions are highly concentrated in urban area,and the weekly cycles,seasonal patterns and long-term trends of tropospheric NO_(2)columns over cities differ from region to region due to different emission sectoral compositions and human activities.In this study,we used satellite observed tropospheric NO_(2)column data to compare the longand short-term NO_(2)column density time series over cities in the United Sates(the U.S.),western Europe and China.The results showed that in all the targeted cities,the outbreak of the Corona Virus Disease in 2019(COVID-19)moved the December peak of the city-level NO_(2)columns forward to November and October or even earlier in 2020 and 2021.On weekly level,cities in the U.S.show the lowest NO_(2)columns ratio on weekend/work day,then come the western European cities,and a weak weekly pattern is seen in Chinese cities.For all the cites,we find a higher weekend/work day NO_(2)ratio in cold seasons than in warm seasons,indicating a higher contribution from NOx emission sectors of residential,industry and power plants in the warm seasons.In the long-term,NO_(2)columns over the U.S.and western European cities declined by a fraction twice that of the regional mean level from 2004 to 2021.In China,NO_(2)columns started to decrease since 2012,at a similar rate between the city and regional level.This work confirms the importance to quantify and control NOx emissions from cities. 展开更多
关键词 NO_(2)columns urban region weekly cycle seasonal pattern long-term trend United States western Europe china
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Effect of CO_(2)flooding in an oil reservoir with strong bottom-water drive in the Tahe Oilfield,Tarim Basin,Northwest China
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作者 Li Zhang Haiying Liao Maolei Cui 《Energy Geoscience》 EI 2024年第1期230-233,共4页
The dissolution and diffusion of CO_(2)in oil and water and its displacement mechanism were investigated by laboratory experiment and numerical simulation for Block 9 in the Tahe oilfield,a sandstone oil reservoir wit... The dissolution and diffusion of CO_(2)in oil and water and its displacement mechanism were investigated by laboratory experiment and numerical simulation for Block 9 in the Tahe oilfield,a sandstone oil reservoir with strong bottom-water drive in Tarim Basin,Northwest China.Such parameters were analyzed as solubility ratio of CO_(2)in oil,gas and water,interfacial tension,in-situ oil viscosity distribution,remaining oil saturation distribution,and oil compositions.The results show that CO_(2)flooding could control water coning and increase oil production.In the early stage of the injection process,CO_(2)expanded vertically due to gravity differentiation,and extended laterally under the action of strong bottom water in the intermediate and late stages.The CO_(2)got enriched and extended at the oil-water interface,forming a high interfacial tension zone,which inhibited the coning of bottom water to some extent.A miscible region with low interfacial tension formed at the gas injection front,which reduced the in-situ oil viscosity by about 50%.The numerical simulation results show that enhanced oil recovery(EOR)is estimated at 5.72%and the oil exchange ratio of CO_(2)is 0.17 t/t. 展开更多
关键词 Strong bottom-water drive reservoir CO_(2)flooding Enhanced oil recovery Coning of bottom water Tahe oilfield Tarim Basin Northwest china
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Drought over China in the 21st Century: Results of RegCM3 被引量:5
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作者 LIU Ke JIANG Da-Bang MA Jian-Yong 《Atmospheric and Oceanic Science Letters》 2012年第6期509-513,共5页
Based on 150-year simulations of a regional climate model, RegCM3, under the Special Report on Emissions Scenarios (SRES) A1B scenario, the effective drought index (EDI) is used to project the future drought change in... Based on 150-year simulations of a regional climate model, RegCM3, under the Special Report on Emissions Scenarios (SRES) A1B scenario, the effective drought index (EDI) is used to project the future drought change in China. During the baseline period 1986-2005, RegCM3 was found to reliably simulate the spatial pattern of drought over the country. Over the 21st century, the regionally averaged EDI should increase, corresponding to a decrease of drought, while the probability of extreme drought events should increase. Geographically, drought should clearly increase in Northeast China, the middle and lower reaches of the Yangtze River valley, Southwest China, and southern Tibet but decrease in most parts of the rest of the country. 展开更多
关键词 china DROUGHT EDI regcm3
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不同用量生物质炭降低华南集约化菜地土壤N_(2)O排放和提高氮肥利用率的效应 被引量:1
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作者 陈宗海 石梦玄 +2 位作者 刘一戈 李博 卢瑛 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第6期1053-1063,共11页
【目的】我国集约化蔬菜种植氮肥施用量大、复种指数高、农事操作频繁,导致土壤氮素损失量大,氮肥利用率低。生物质炭施用可有效改善土壤物理、化学和生物学性质,进而影响土壤氮素循环以及作物产量。比较不同生物质炭用量对土壤N_(2)O... 【目的】我国集约化蔬菜种植氮肥施用量大、复种指数高、农事操作频繁,导致土壤氮素损失量大,氮肥利用率低。生物质炭施用可有效改善土壤物理、化学和生物学性质,进而影响土壤氮素循环以及作物产量。比较不同生物质炭用量对土壤N_(2)O减排和作物产量的影响及作用机理,为生物质炭在蔬菜栽培中的应用提供指导。【方法】田间试验在华南地区进行,在连续两年内共种植4茬多次收获蔬菜。试验设置不施氮肥(CK)、常规施氮(NF)、常规施氮+20 t/hm^(2)生物质炭(NB20)和常规施氮+40 t/hm^(2)生物质炭(NB40)处理,采用静态暗箱—气相色谱法对两年蔬菜生长季的土壤N_(2)O排放量和蔬菜产量进行测定,田间试验结束后采集土样测定土壤理化性质和酶活性。【结果】生物炭施用两年后,NB20和NB40处理的土壤全氮、pH、有效磷和脲酶活性均显著高于NF,NB20处理的pH和有效磷含量又显著高于NB40处理。两年试验NF处理菜地土壤N_(2)O排放通量范围为42.8~7233.0μg/(m^(2)·h),生物质炭处理为28.4~3188.1μg/(m^(2)·h),温度、季节和氮肥施用是引起波动的主要因素。与NF处理相比,2018、2019年NB20处理的N_(2)O累积排放量分别显著降低了64.3%、66.9%,NB40处理分别显著降低了55.8%、62.5%,但两处理之间无显著差异。与NF处理相比,NB20处理的蔬菜产量显著增加了10.1%~29.10%,产量尺度N_(2)O排放显著降低了56.4%~74.4%,氮素吸收量因而显著增加了13.9%~32.9%,两年之间多数指标变化不显著;NB40处理第一年的增产、降排效果与NB20处理无显著差异,第二年的产量和氮素利用率显著低于NB20处理,也低于第一年。相关性分析和冗余分析表明,土壤pH是影响N_(2)O排放的主要因素,土壤有效磷、pH和有机碳是影响蔬菜产量的主要因素。【结论】在华南集约化蔬菜生产中,配施生物质炭能显著缓解大量氮肥施用产生的土壤酸化,增加土壤蛋白酶和脲酶活性,进而抑制施肥诱发的土壤N_(2)O排放,提高蔬菜的氮吸收量,最终增加蔬菜产量和氮素利用率。与施用40 t/hm^(2)的处理相比,施用20 t/hm^(2)生物炭的处理提升土壤pH和产量的效果更稳定,降低单位产量N_(2)O排放和提升蔬菜氮素利用效率的效果更佳,因此常规施氮+20 t/hm^(2)生物质炭是可推荐的减排增效措施。 展开更多
关键词 生物质炭 华南地区 集约化菜地 N_(2)O 氮素利用率
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Temporal and Spatial Distribution of SARS-CoV-2 Aerosols in a Large-Scale Fangcang Shelter Hospital in Shanghai,China
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作者 Jiafu Jiang Zhe Yin +23 位作者 Jing Li Leili Jia Rulin He Wenhui Yang Jihu Yang Hang Fan Sen Zhang Yunfei Wang Zengming Zhao Haoran Peng Lizhong Li Yi Yang Shi-Yong Fan Rong Xiang Jianshu Guo Jinjin Wang Juanning Wei Fengling Zhou Ding Liu Ping Zhao Yujun Cui Yunxi Liu Dongsheng Zhou Gang Dong 《Engineering》 SCIE EI CAS CSCD 2023年第9期222-233,共12页
The coronavirus disease 2019(COVID-19)pandemic caused by frequently mutating severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has had a worldwide impact.However,detailed data on the potential aerosol transmi... The coronavirus disease 2019(COVID-19)pandemic caused by frequently mutating severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has had a worldwide impact.However,detailed data on the potential aerosol transmission of SARS-CoV-2 in real-world and controlled laboratory settings remain sparse.During the COVID-19 pandemic in Shanghai,China in 2022,samples were collected in a Fangcang shelter hospital,a large-scale temporary hospital rapidly built by converting the existing National Exhibition and Convention Center(Shanghai)into a health care facility.Aerosol samples at different sites and intervals around patients and in public areas,surface samples,and pharyngeal swab samples from corresponding patients were included.Samples were tested for SARS-CoV-2 using real-time quantitative polymerase chain reaction(RT-qPCR)assays,followed by sequencing if the cycle threshold(Ct)value was<30.The positivity rate for SARS-CoV-2 in aerosol samples was high in contaminated zones(37.5%,104/277),especially around the bed(41.2%,68/165)and near ventilation inlets(45.2%,14/31).The prevalence of SARS-CoV-2 around the bed,public areas,and air inlets of exhaust vents fluctuated and was closely related to the positivity rate among patients at corresponding sampling sites.Some surface samples of different personal protective equipment from medical staff had high positivity rates.Sixty sequences of joined ORF1ab and spike genes obtained from sixty samples represented two main clusters of Omicron SARS-CoV-2.There was consistency in virus sequences from the same patient and their environment,and the detected virus sequences matched those of virus strains in circulation during the collection periods,which indicated a high likelihood of cross-contamination in the Fangcang shelter hospital.In summary,the results provide a quantitative and real landscape of the aerosol transmission of SARS-CoV-2 and a patient-centered view of contamination in large and enclosed spaces and offer a useful guide for taking targeted measures to avoid nosocomial infections during the management of SARS-CoV-2 or other respiratory virus diseases in a Fangcang shelter hospital. 展开更多
关键词 Coronavirus disease 2019 Severe acute respiratory syndrome coronavirus 2 AEROSOLS Fangcang shelter hospital china
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Comparative assessment of nitrogen fixation rate by ^(15)N_(2) tracer assays in the South China Sea
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作者 Danyang Li Minfang Zheng +5 位作者 Yusheng Qiu Limin Lai Nengwang Chen Hongmei Jing Run Zhang Min Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第1期75-82,共8页
Nitrogen fixation is one of the most important sources of new nitrogen in the ocean and thus profoundly affects the nitrogen and carbon biogeochemical processes.The distribution,controlling factors,and flux of N2 fixa... Nitrogen fixation is one of the most important sources of new nitrogen in the ocean and thus profoundly affects the nitrogen and carbon biogeochemical processes.The distribution,controlling factors,and flux of N2 fixation in the global ocean remain uncertain,partly because of the lack of methodological uniformity.The^(15)N_(2)tracer assay(the original bubble method→the^(15)N_(2)-enriched seawater method→the modified bubble method)is the mainstream method for field measurements of N2 fixation rates(NFRs),among which the original bubble method is the most frequently used.However,accumulating evidence has suggested an underestimation of NFRs when using this method.To improve the availability of previous data,we compared NFRs measured by three^(15)N_(2)tracer assays in the South China Sea.Our results indicate that the relationship between NFRs measured by the original bubble method and the^(15)N_(2)-enriched seawater method varies obviously with area and season,which may be influenced by incubation time,diazotrophic composition,and environmental factors.In comparison,the relationship between NFRs measured by the original bubble method and the modified bubble method is more stable,indicating that the N2 fixation rates based on the original bubble methods may be underestimated by approximately 50%.Based on this result,we revised the flux of N2 fixation in the South China Sea to 40 mmol/(m2·a).Our results improve the availability and comparability of literature NFR data in the South China Sea.The comparison of the^(15)N_(2)tracer assay for NFRs measurements on a larger scale is urgently necessary over the global ocean for a more robust understanding of the role of N2 fixation in the marine nitrogen cycle. 展开更多
关键词 N2 fixation rate South china Sea ^(15)N_(2)tracer assay
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Mapping upland crop–rice cropping systems for targeted sustainable intensification in South China
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作者 Bingwen Qiu Linhai Yu +4 位作者 Peng Yang Wenbin Wu Jianfeng Chen Xiaolin Zhu Mingjie Duan 《The Crop Journal》 SCIE CSCD 2024年第2期614-629,共16页
Upland crop-rice cropping systems(UCR)facilitate sustainable agricultural intensification.Accurate UCR cultivation mapping is needed to ensure food security,sustainable water management,and rural revitalization.Howeve... Upland crop-rice cropping systems(UCR)facilitate sustainable agricultural intensification.Accurate UCR cultivation mapping is needed to ensure food security,sustainable water management,and rural revitalization.However,datasets describing cropping systems are limited in spatial coverage and crop types.Mapping UCR is more challenging than crop identification and most existing approaches rely heavily on accurate phenology calendars and representative training samples,which limits its applications over large regions.We describe a novel algorithm(RRSS)for automatic mapping of upland crop-rice cropping systems using Sentinel-1 Synthetic Aperture Radar(SAR)and Sentinel-2 Multispectral Instrument(MSI)data.One indicator,the VV backscatter range,was proposed to discriminate UCR and another two indicators were designed by coupling greenness and pigment indices to further discriminate tobacco or oilseed UCR.The RRSS algorithm was applied to South China characterized by complex smallholder rice cropping systems and diverse topographic conditions.This study developed 10-m UCR maps of a major rice bowl in South China,the Xiang-Gan-Min(XGM)region.The performance of the RRSS algorithm was validated based on 5197 ground-truth reference sites,with an overall accuracy of 91.92%.There were7348 km^(2) areas of UCR,roughly one-half of them located in plains.The UCR was represented mainly by oilseed-UCR and tobacco-UCR,which contributed respectively 69%and 15%of UCR area.UCR patterns accounted for only one-tenth of rice production,which can be tripled by intensification from single rice cropping.Application to complex and fragmented subtropical regions suggested the spatiotemporal robustness of the RRSS algorithm,which could be further applied to generate 10-m UCR datasets for application at national or global scales. 展开更多
关键词 Cropping-pattern mapping Paddy rice Sentinel-1/2 china Sustainable intensification
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Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China
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作者 ZHANG Sumei ZHANG Yuan ZHAO Hongmei 《Chinese Geographical Science》 SCIE CSCD 2024年第3期548-563,共16页
The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate ... The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data. 展开更多
关键词 crop residue burning burned area Sentinel-2 Multi Spectral Instrument(MSI) logistic regression Songnen Plain china
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NCAR RegCM2对东亚区域气候的模拟试验 被引量:62
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作者 罗勇 赵宗慈 《应用气象学报》 CSCD 北大核心 1997年第A00期124-133,共10页
利用垂直、水平高分辨率的区域气候模式NCARRegCM2(1996年5月最新版本)进行了1991年夏季(5~8月)东亚洪涝个例的区域气候数值模拟.与观测事实的比较表明,该模式能够较好地再现出该个例我国江淮流域—日本季... 利用垂直、水平高分辨率的区域气候模式NCARRegCM2(1996年5月最新版本)进行了1991年夏季(5~8月)东亚洪涝个例的区域气候数值模拟.与观测事实的比较表明,该模式能够较好地再现出该个例我国江淮流域—日本季风降水的主要时空特征和环流形势异常等. 展开更多
关键词 区域气候模拟 江淮流域 洪涝 regcm2 模拟试验
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口蹄疫病毒强毒株China/99 P2区核苷酸序列测定及比较分析 被引量:2
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作者 张显升 赵启祖 +6 位作者 刘在新 江鹏斐 常惠芸 陈应理 李冬 魏怀录 谢庆阁 《畜牧兽医学报》 CAS CSCD 北大核心 2002年第5期496-500,共5页
以口蹄疫病毒强毒株China/99RNA为反转录模板 ,用一对特异性引物扩增目的cDNA ,然后与 pGEM TEasy载体连接并转化JM10 9菌株 ,再经重组质粒电泳、PCR和EcoR1酶切鉴定。序列测定和分析结果表明 ,该强毒株与A12、O1K和TW 45毒株的核苷酸... 以口蹄疫病毒强毒株China/99RNA为反转录模板 ,用一对特异性引物扩增目的cDNA ,然后与 pGEM TEasy载体连接并转化JM10 9菌株 ,再经重组质粒电泳、PCR和EcoR1酶切鉴定。序列测定和分析结果表明 ,该强毒株与A12、O1K和TW 45毒株的核苷酸差异率分别为 7 78%、6 6 2 %和 13 19%。推导的氨基酸序列差异率分别为 1 2 3%、1 84%和 5 73%。 4个毒株序列比较发现 ,China/99、O1K和TW 45三毒株的 2A/2B连接处为甘氨酸 /脯氨酸 ,A12 为精氨酸 /脯氨酸 ,而且T C转换率和A G转换率较高 ,是点突变的热点核苷酸。氨基酸差异主要存在于 2B和 2C蛋白中 ,2A基因较为保守。 2B蛋白的第 1 4,6 3 6 7,73 78,83 91,116 12 1和 12 6 131区域 ,2A蛋白的第 4 9区域和 2C蛋白的第 9 13,2 2 2 5 ,91 96 ,15 0 15 9,179 188,2 0 1 2 0 7和 2 5 8 2 6 2区域可能是重要的活性中心。 展开更多
关键词 口蹄疫病毒 china/99P2 核苷酸序列 比较分析
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区域气候模式RegCM2对标量粗糙度的敏感性试验 被引量:1
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作者 和渊 苏炳凯 赵鸣 《气象科学》 CSCD 北大核心 2001年第2期136-146,共11页
在地气通量的计算中 ,一般没有考虑温度、水汽、动量的相应粗糙度之间的不同 ,本文将标量粗糙度 Z0 T和 Z0 q引入区域气候模式 Reg CM2的陆面过程BATS中 ,用 1991年 6月与 7月的观测资料作了三组敏感性试验 ,并同实况进行了比较。结果表... 在地气通量的计算中 ,一般没有考虑温度、水汽、动量的相应粗糙度之间的不同 ,本文将标量粗糙度 Z0 T和 Z0 q引入区域气候模式 Reg CM2的陆面过程BATS中 ,用 1991年 6月与 7月的观测资料作了三组敏感性试验 ,并同实况进行了比较。结果表明 :在区域气候模式 Reg CM2中引入标量粗糙度后 ,提高了地气间感热通量与潜热通量的计算精度 ,改善了地表温度和地面比湿的模拟 ,进而改变了降水的模拟 ,表明区域气候模式对标量粗糙度是敏感的 ,并且在晴天状况下更为敏感。 展开更多
关键词 标量粗糙度 数值试验 敏感性 区域气候模式regcm2 温度 水汽 动量
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基于ST-ConvLSTM的南海海表面CO_(2)分压的空间和时间序列预测 被引量:1
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作者 高宇 李爽 +1 位作者 郝鹏 宋金宝 《海洋与湖沼》 CAS CSCD 北大核心 2023年第6期1573-1585,共13页
海表面二氧化碳分压(pCO_(2))的未来变化趋势,对统计评估全球碳收支以及理解全球气候变化背景下的海洋酸化现象至关重要。目前传统的海面pCO_(2)预测方法大部分基于有限的实测数据,然而实测数据存在着时间和地理方面的制约,且计算成本... 海表面二氧化碳分压(pCO_(2))的未来变化趋势,对统计评估全球碳收支以及理解全球气候变化背景下的海洋酸化现象至关重要。目前传统的海面pCO_(2)预测方法大部分基于有限的实测数据,然而实测数据存在着时间和地理方面的制约,且计算成本较高。近年来,随着时空观测数据的爆炸性增长,基于深度学习的数据驱动模型在海表面pCO_(2)预测方面中表现出良好的潜力。然而,由于多种环境因素与海表面pCO_(2)之间的关系错综复杂,到目前为止尚无十分简单有效的相关模型来对海表面pCO_(2)进行预测。为应对这一挑战,利用时空卷积长短时记忆神经网络(ST-ConvLSTM)模型,通过海面温度(sea surface temperature,SST)、海面盐度(sea surface salinity,SSS)、叶绿素a浓度(chl a)和海面pCO_(2)数据,预测南海的海面pCO_(2),并将2019年1~12月的数据作为测试集对模型的表现进行了验证。结果显示,ST-ConvLSTM模型的预测因子均方根误差、平均绝对误差和决定系数分别为0.981 Pa、0.711 Pa和0.997。对比卷积LSTM(ConvLSTM)、随机森林和广义回归神经网络(generalized regression neural network,GRNN)三种方法,证实本文所提出的方法在解决南海pCO_(2)预测问题上是可靠的。 展开更多
关键词 ST-ConvLSTM模型 中国南海 海表面二氧化碳分压 深度学习
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bauma China 2012高空作业机械观感
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作者 姚继蔚 孙宽 《建筑机械》 2013年第2期32-37,4,共6页
高空作业机械是一种将作业人员、工具.材料等通过作业平台举升到空中指定位置进行各种安装、维修等作业的专用机械.广泛应用于船舶制造.建筑装潢.市政园林.电力通信、公路交通、机场车站、广告、港口等领域。近年来.随着我国经济... 高空作业机械是一种将作业人员、工具.材料等通过作业平台举升到空中指定位置进行各种安装、维修等作业的专用机械.广泛应用于船舶制造.建筑装潢.市政园林.电力通信、公路交通、机场车站、广告、港口等领域。近年来.随着我国经济的不断发展.对高空作业安全性的日益重视.高空作业机械的市场需求逐渐升温. 展开更多
关键词 BAUMA china 201 2 高空作业机械
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恩格列净联合利拉鲁肽治疗2型糖尿病伴心力衰竭的效果分析 被引量:3
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作者 郭明笛 李雪粉 《中国处方药》 2023年第8期127-131,共5页
目的 探究恩格列净联合利拉鲁肽治疗2型糖尿病伴心衰患者的效果。方法 选取2020年3月~2022年12月在泰达国际心血管病医院就诊的2型糖尿病伴心衰患者122例,按照随机数字法分为对照组(n=61)和观察组(n=61),其中对照组采用利拉鲁肽治疗,观... 目的 探究恩格列净联合利拉鲁肽治疗2型糖尿病伴心衰患者的效果。方法 选取2020年3月~2022年12月在泰达国际心血管病医院就诊的2型糖尿病伴心衰患者122例,按照随机数字法分为对照组(n=61)和观察组(n=61),其中对照组采用利拉鲁肽治疗,观察组采用恩格列净联合利拉鲁肽治疗。评估两组患者的临床疗效、血糖水平、心功能、血清指标、不良反应及生活质量。结果 观察组的总有效率、简易生活质量评价量表(SF-36)中各个项目评分、左心室射血分数(LVEF)、心输出量(CO)、每搏输出量(SV)水平均高于对照组(P <0.05);治疗后观察组的餐后2 h血糖(2 hPG)、糖化血红蛋白(HbA1c)、空腹血糖(FPG)、B型利钠肽(BNP)、N末端B型利钠肽(NT-proBNP)、超敏C反应蛋白(hs-CRP)、白细胞介素-6(IL-6)水平均低于对照组(P <0.05)。结论 2型糖尿病伴心衰患者采用恩格列净联合利拉鲁肽治疗效果显著,降低血糖水平,改善心功能,调节血清指标,提升患者的生活质量。 展开更多
关键词 恩格列净 利拉鲁肽 2型糖尿病 心衰 血糖水平
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China e-Auto Hub面世——中企通信与GXS通力合作打造汽车产业B2B数据交换中心
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作者 龚淑娟 《汽车制造业》 2006年第5期16-17,共2页
China e-Auto Hub将为中国汽车行业提供安全且可订制的B2B电子商务平台,使其能够在此基础上与其全球供应链贸易伙伴进行在线交易。
关键词 china 数据交换中心 B2B HUB 汽车产业 合作 通信 面世 电子商务平台 全球供应链
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Comparison of convective parameterizations in RegCM4 experiments over China with CLM as the land surface model 被引量:36
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作者 GAO Xue-Jie SHI Ying Filippo GIORGI 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第4期246-254,共9页
in the latest version of the international Centre for Theoretical Physics' regional climate model, RegCM4, CLM was introduced as a new land surface scheme. The performance over China of RegCM4-CLM with different conv... in the latest version of the international Centre for Theoretical Physics' regional climate model, RegCM4, CLM was introduced as a new land surface scheme. The performance over China of RegCM4-CLM with different convection schemes is analyzed in this study, based on a series of short- term experiments.The model is driven by ERA-Interim data at a grid spacing of 25 km.The convection schemes employed are: Emanuel; Grell; Emanuel over land and Grell over ocean; Grell over land and Emanuel over ocean; and Tiedtke. The simulated mean surface air temperature and precipitation in December-February-January and June-July-August are compared against observation. In general, better performance of Emanuel is found both for temperature and precipitation, and in both seasons. Thus, the model physics of CLM and Emanuel for the land surface processes and convection, respectively, are recommended for further application of RegCM4 over the China region. The de^ciencies that remain in the model arealso outlined and discussed. 展开更多
关键词 Regional climate model china regcm4 temperatureprecipitation
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东海陆架盆地咸水层CO_(2)封存地质条件适宜性评价
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作者 赵勇 李久娣 +4 位作者 杨鹏程 沈珊 王丹萍 董鑫 朱睿哲 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2023年第4期129-139,共11页
系统分析了东海陆架盆地咸水层CO_(2)封存的关键地质要素,认为在构造和沉积演化的控制下盆地表现出“整体封存有利、东西封存差异”的特征,东部坳陷裂陷充分,构造单元面积大、沉积厚并且地层发育全,潜在封存层系为中新统和渐新统;西部... 系统分析了东海陆架盆地咸水层CO_(2)封存的关键地质要素,认为在构造和沉积演化的控制下盆地表现出“整体封存有利、东西封存差异”的特征,东部坳陷裂陷充分,构造单元面积大、沉积厚并且地层发育全,潜在封存层系为中新统和渐新统;西部坳陷裂陷早,构造单元面积相对小、地层薄并且地层时代老,CO_(2)封存的有利储盖组合为古新统—始新统。对各二级构造单元咸水层CO_(2)的封存量进行了计算,结果表明,东海陆架盆地D级咸水层CO_(2)封存量为636.2亿t,其中东部坳陷的西湖凹陷和基隆凹陷封存量最大,均超过100亿t,其次为西部坳陷的瓯江凹陷,达到64亿t。结合关键封存要素建立了东海陆架盆地D级CO_(2)地质储存适宜性评价指标体系,并对各评价单元进行了适宜性评价,结果表明西湖凹陷和瓯江凹陷CO_(2)封存适宜性最好,为东海陆架盆地CO_(2)封存的有利远景区。 展开更多
关键词 CO_(2)封存 封存潜力 封存适宜性 东海陆架盆地
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