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祁连山绿色发展:从生态治理到生态恢复 被引量:48
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作者 李新 勾晓华 +12 位作者 王宁练 盛煜 金会军 祁元 宋晓谕 侯扶江 李育 赵长明 邹松兵 王宏伟 郑东海 陈莹莹 牛晓蕾 《科学通报》 EI CAS CSCD 北大核心 2019年第27期2928-2937,共10页
在祁连山生态环境经重锤整治、生态恢复初显成效之际,第二次青藏高原综合科学考察之'祁连山综合考察'全面开启.优先围绕生态系统与生态安全、固体水库动态变化、人类活动变化与生态生计影响三大关键任务,开展天-空-地一体化考察... 在祁连山生态环境经重锤整治、生态恢复初显成效之际,第二次青藏高原综合科学考察之'祁连山综合考察'全面开启.优先围绕生态系统与生态安全、固体水库动态变化、人类活动变化与生态生计影响三大关键任务,开展天-空-地一体化考察,定量核算了生态环境整治后局部的生态环境收益与经济损失,并基于远程耦合方法核算了祁连山的全局生态系统服务价值.研究发现:生态环境整治提升了生态环境服务价值;暖湿化背景下生态系统整体向好,珍稀物种种群扩大,但对局部草原过牧管控不力导致退化;冰川冰储量亏损加剧,冰川融水径流贡献率将越过临界点;过去10多年冻土融化释放的水量约为1.18 km3/a,相当于祁连山出山河流年径流总量的10%;祁连山全局生态系统服务估算价值高达10676(±1601)亿元,远高于2017年区域经济损失的53.09亿元.鉴于祁连山对于全国的巨大生态价值,建议国家加大生态补偿力度,实现祁连山生态生计双赢的绿色发展.祁连山综合科学考察成果可为祁连山国家公园建设,以及'山水林田湖草'系统保护与修复提供详实数据和决策依据,为'丝绸之路经济带'沿线国家流域治理提供典型案例和科学支撑. 展开更多
关键词 祁连山 生态生计双赢 冰川储量 多年冻土释水量 生态系统与生物多样性
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Assessment of the GPM and TRMM Precipitation Products Using the Rain Gauge Network over the Tibetan Plateau 被引量:21
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作者 Sijia ZHANG donghai WANG +2 位作者 zhengkun QIN Yaoyao zheng Jianping GUO 《Journal of Meteorological Research》 SCIE CSCD 2018年第2期324-336,共13页
Using high-quality hourly observations from national-level ground-based stations, the satellite-based rainfall products from both the Global Precipitation Measurement(GPM) Integrated Multisatellit E Retrievals for ... Using high-quality hourly observations from national-level ground-based stations, the satellite-based rainfall products from both the Global Precipitation Measurement(GPM) Integrated Multisatellit E Retrievals for GPM(IMERG) and its predecessor, the Tropical Rainfall Measuring Mission(TRMM) Multi-satellite Precipitation Analysis(TMPA), are statistically evaluated over the Tibetan Plateau(TP), with an emphasis on the diurnal variation.The results indicate that:(1) the half-hourly IMERG rainfall product can explicitly describe the diurnal variation over the TP, but with discrepancies in the timing of the greatest precipitation intensity and an overestimation of the maximum rainfall intensity over the whole TP. In addition, the performance of IMERG on the hourly timescale, in terms of the correlation coefficient and relative bias, is different for regions with sea level height below or above 3500 m;(2) the IMERG products, having higher correlation and lower root-mean-square error, perform better than the TMPA products on the daily and monthly timescales; and(3) the detection ability of IMERG is superior to that of TMPA, as corroborated by a higher Hanssen and Kuipers score, a higher probability of detection, a lower false alarm ratio, and a lower bias. Compared to TMPA, the IMERG products ameliorate the overestimation across the TP. In conclusion,GPM IMERG is superior to TRMM TMPA over the TP on multiple timescales. 展开更多
关键词 Global Precipitation Measurement Tropical Rainfall Measuring Mission Tibetan Plateau PRECIPITATION
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升温速率对准东褐煤热解特性及煤焦孔隙结构的影响 被引量:18
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作者 张肖阳 周滨选 +3 位作者 安东海 崔琳 郑瑛 董勇 《煤炭学报》 EI CAS CSCD 北大核心 2019年第2期604-610,共7页
为了简化活性焦的制备工艺流程,降低其生产成本,同时拓宽准东褐煤利用途径,需要对准东褐煤热解过程进行更深入的研究。利用热重(TGA)技术考察了准东褐煤在不同升温速率(10,20,30,40和50℃/min)热解失重特性并采用等转化率法分析了其动... 为了简化活性焦的制备工艺流程,降低其生产成本,同时拓宽准东褐煤利用途径,需要对准东褐煤热解过程进行更深入的研究。利用热重(TGA)技术考察了准东褐煤在不同升温速率(10,20,30,40和50℃/min)热解失重特性并采用等转化率法分析了其动力学参数,同时利用程序升温和快速热解在终温为800℃条件下制备出活性焦SC1和SC2。采用氮吸附仪(BET)获得煤焦的孔隙结构参数,利用红外吸收光谱仪(FT-IR)和拉曼仪光谱仪(Raman)分别获取煤焦大分子结构中的官能团和碳骨架结构信息。研究结果表明,基于热重法分析出准东褐煤热解动力学参数,活化能和指前因子变化范围为38. 89~229. 13 kJ/mol和108. 26~1. 18×109s-1。升温速率为30℃/min时,有足够热量促进煤焦内部有机结构分解生成大量挥发分,煤焦内部形成合理的温度梯度,阻碍了热缩聚反应造成孔隙阻塞,挥发分顺利释放促进了孔隙结构形成。程序升温热解焦SC1烧失率为46. 5%,比表面积为312. 91 m^2/g,孔容为0. 178 cm3/g,平均孔径为2. 271 nm;而快速热解焦SC2烧失率为37. 3%,比表面积达到424. 25 m^2/g,孔容为0. 189 cm3/g,平均孔径2. 342 nm,以微孔为主,结构参数明显好于SC1。快速热解炭化制备活性焦前驱体,促进煤焦生成大量无定形结构和缺陷结构,利于活化阶段微孔孔隙结构的构筑。 展开更多
关键词 升温速率 褐煤 快速热解 活性焦 孔隙结构
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双巷掘进留窄小煤柱布置方式及围岩稳定性控制技术 被引量:15
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作者 黄万朋 赵同阳 +3 位作者 江东海 郭晓胜 郑永胜 王学文 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2023年第3期617-629,共13页
为解决传统双巷掘进资源采出率低和沿空掘巷采掘接替紧张难题,以翟镇煤矿下组煤一采区11502工作面为工程试验对象,创新性提出留窄小煤柱双巷同时掘进巷道的布置方法,同时构建小煤柱高强复合加固支护技术。采用理论分析、试验测试结合数... 为解决传统双巷掘进资源采出率低和沿空掘巷采掘接替紧张难题,以翟镇煤矿下组煤一采区11502工作面为工程试验对象,创新性提出留窄小煤柱双巷同时掘进巷道的布置方法,同时构建小煤柱高强复合加固支护技术。采用理论分析、试验测试结合数值模拟等综合研究方法,对留窄小煤柱双巷掘进布置原理及煤柱加固支护技术进行深入研究探索。结果表明,双巷掘进留窄小煤柱技术能够实现采区工作面顺序接替,有效提高采区采出率;提出的小煤柱综合加固支护技术以超前断顶卸压、对穿锚索提高煤柱自身承载力以及钢管混凝土墩柱高强辅助加强支护为主体,避免了小煤柱过早进入塑性状态而发生整体失稳破坏,能够有效保持长期稳定。基于覆岩组合结构理论建立煤柱–顶板结构力学模型,研究煤柱上方支承压力分布规律与大小,建立双巷掘进小煤柱加固支护设计方法。通过数值模拟验证,该技术与传统沿空掘巷相比,能够更好地控制巷道围岩变形,煤柱体的帮鼓变形量和巷道变形量均得到了有效降低。 展开更多
关键词 采矿工程 沿空掘巷 小煤柱 双巷布置 对穿锚索 钢管混凝土墩柱
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Development of a daily soil moisture product for the period of2002–2011 in Chinese mainland 被引量:11
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作者 Kun YANG Yingying CHEN +5 位作者 Jie HE Long ZHAO Hui LU Jun QIN donghai zheng Xin LI 《Science China Earth Sciences》 SCIE EI CAS CSCD 2020年第8期1113-1125,共13页
Soil moisture is an essential climate variable(ECV) concerned widely. Due to its high spatial variability, it is costly to measure soil moisture at tens of kilometers scale. In this study, a ten-year(2002–2011) daily... Soil moisture is an essential climate variable(ECV) concerned widely. Due to its high spatial variability, it is costly to measure soil moisture at tens of kilometers scale. In this study, a ten-year(2002–2011) daily soil moisture dataset at 0.25° spatial resolution for Chinese mainland was produced through assimilating the Advanced Microwave Scanning Radiometer for Earth Observing System(AMSR-E) brightness temperature(TB) data into a land surface model(LSM). The obtained soil moisture data was evaluated against soil moisture-measuring networks deployed in two wet areas and one dry area of the Tibetan Plateau.The results show that for the wet areas the accuracy of the soil moisture product obtained from the assimilation is considerably higher than that of both AMSR-E official soil moisture products and land surface simulation results, and for the dry area their accuracy is comparable to each other. The spatial pattern of the soil moisture from the new product is consistent with that of soil porosity from an independent survey-based dataset, further confirming the credibility of the new product. According to this product, the transition regions in China show stronger seasonal variation of soil moisture than dry and wet regions, and drier regions have stronger inter-annual variability of soil moisture than wetter regions, particularly during transitional seasons(spring and autumn). The soil moisture product is accessible at the National Tibetan Plateau Data Center. 展开更多
关键词 Soil moisture Microwave signal Data assimilation Spatiotemporal variability Tibetan Plateau
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不同烟气组分对粉状活性焦吸附汞的影响机理 被引量:9
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作者 安东海 韩晓林 +3 位作者 程星星 周滨选 郑瑛 董勇 《化工学报》 EI CAS CSCD 北大核心 2019年第4期1575-1582,共8页
在模拟燃煤热烟气为热源和介质条件下,以准东褐煤为原料,通过一维沉降炉进行炭化活化(一步法)制备粉状活性焦,考察了活性焦对Hg^0的吸附能力,探索了SO_2、H_2O、O_2、CO_2、H_2O+O_2、SO_2+O_2及H_2O+SO_2+O_2气氛对活性焦吸附Hg^0的影... 在模拟燃煤热烟气为热源和介质条件下,以准东褐煤为原料,通过一维沉降炉进行炭化活化(一步法)制备粉状活性焦,考察了活性焦对Hg^0的吸附能力,探索了SO_2、H_2O、O_2、CO_2、H_2O+O_2、SO_2+O_2及H_2O+SO_2+O_2气氛对活性焦吸附Hg^0的影响机理。结果表明:一步法获得的活性焦对Hg^0具有较高的吸附性能。N_2气氛作对比,H_2O、H_2O+O_2、CO_2和SO_2气氛下抑制活性焦对Hg^0的吸附;O_2、SO_2+O_2和H_2O+SO_2+O_2促进活性焦对Hg^0的吸附。通过Hg 4f的XPS分析证明了不同气氛组成对活性焦吸附Hg^0的抑制和促进机理。H_2O覆盖在活性焦活性位上和堵塞孔隙而抑制活性焦对Hg^0的吸附;SO_2与Hg^0在活性焦上发生竞争吸附而抑制对Hg^0的吸附;CO_2吸附在活性焦微孔上而抑制对Hg^0的吸附;O_2气氛下主要形成了HgO, SO_2+O_2气氛下Hg^0被氧化成HgSO_3,进一步氧化成HgSO_4; H_2O+SO_2+O_2气氛下,Hg^0被氧化成HgO和HgSO_4。 展开更多
关键词 粉状活性焦 一步法 汞吸附 影响机理
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浅谈中医药在防治新型冠状病毒肺炎中的应用 被引量:6
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作者 郑东海 郑伟达 +1 位作者 郑伟鸿 李玲美 《中医临床研究》 2020年第33期22-26,共5页
2019年12月末中国暴发了新型冠状病毒肺炎(Corona Virus Disease 2019,COVID-19)(简称新冠肺炎)疫情,中医药在防治疫情过程中疗效显著。国家先后发布的7版《新型冠状病毒感染的肺炎诊疗方案》和各省市自治区先后出台的相关诊疗方案和建... 2019年12月末中国暴发了新型冠状病毒肺炎(Corona Virus Disease 2019,COVID-19)(简称新冠肺炎)疫情,中医药在防治疫情过程中疗效显著。国家先后发布的7版《新型冠状病毒感染的肺炎诊疗方案》和各省市自治区先后出台的相关诊疗方案和建议中特别提出,要发挥中医药在防治疫情中的独特优势,坚持中西医结合,优势互补原则,做好防控疫情。中医专家郑伟达教授结合从医40余年的经验总结防治新冠肺炎方剂10首,以期为临床防治新冠肺炎提供思路和方案,更好地发挥发展中医药防控“疫病”的作用。 展开更多
关键词 新型冠状病毒肺炎 中医药 防治
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溱潼凹陷西斜坡阜三段隐蔽油藏勘探开发一体化实践 被引量:7
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作者 李东海 昝灵 +5 位作者 黄文欢 余文端 马晓东 郑永旺 周韬 印燕铃 《油气藏评价与开发》 CSCD 2021年第3期281-290,共10页
针对溱潼凹陷西斜坡浅层阜三段构造油藏不发育,深层低渗透油藏效益开发难度大的难点,采用沉积建模技术和波形反演等技术,深化成藏规律研究,评价出浅层阜三段构造—岩性油藏的有利区。自然电位—波形反演技术能清晰刻画5 m左右的砂体。... 针对溱潼凹陷西斜坡浅层阜三段构造油藏不发育,深层低渗透油藏效益开发难度大的难点,采用沉积建模技术和波形反演等技术,深化成藏规律研究,评价出浅层阜三段构造—岩性油藏的有利区。自然电位—波形反演技术能清晰刻画5 m左右的砂体。建立溱潼西斜坡阜三段浅湖滩坝沉积—成藏模式,勘探开发一体化研究、部署和实施,发现了南华—仓吉千万吨级优质储量阵地,探井成功率70%。实施“决策部署、地质工程、组织运行一体化”的建产模式,推进溱潼西斜坡阜三段构造—岩性油藏评价,落实可动用储量1003×10^(4) t,建产能17.5×10^(4) t。原油盈亏平衡点由81美元/桶下降至46美元/桶,实现了隐蔽油藏的高效勘探开发。 展开更多
关键词 勘探开发一体化 隐蔽油藏 薄砂层 阜三段 西斜坡 溱潼凹陷
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基于介电特性的青萝卜干燥品质预测模型 被引量:7
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作者 高亚平 安峰 +4 位作者 赵东海 吴龙 徐庆 郑兆启 王瑞芳 《天津科技大学学报》 CAS 2019年第4期63-71,共9页
以青萝卜为实验物料,利用网络分析仪,采用同轴探头法测量了在16~3500MHz的频率范围内,湿基含水率为15%~93.20%,物料温度为(36±1)℃的青萝卜的介电常数ε'和介质损耗因子ε".分析了频率、含水率、糖度、密度与介电特性的关... 以青萝卜为实验物料,利用网络分析仪,采用同轴探头法测量了在16~3500MHz的频率范围内,湿基含水率为15%~93.20%,物料温度为(36±1)℃的青萝卜的介电常数ε'和介质损耗因子ε".分析了频率、含水率、糖度、密度与介电特性的关系,建立了915MHz和2450MHz下介电特性与含水率、糖度、密度的关联模型,检验了基于介电特性预测含水率、糖度、密度的可行性.结果表明:在16~3500MHz频率段内,介电常数ε'和介质损耗因子ε"随着频率的增大而减小.介电常数ε'随着含水率的增大而增大,介质损耗因子ε"在湿基含水率为15%~60%时,随着含水率的增大而增大,之后随着含水率的增大而降低.糖度与含水率呈负相关.可用二元一次方程描述含水率、糖度、密度与介电特性的关系,对模型进行方差分析,各模型的决定系数均大于0.92,P值小于0.05,表明所得基于介电特性预测干燥过程中青萝卜的含水率、糖度、密度的模型是准确的. 展开更多
关键词 青萝卜 介电特性 频率 湿基含水率 糖度 密度
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基于分布参数模型的混合输电线路精确测距及重合闸方案的研究 被引量:5
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作者 杨东海 许艳华 +2 位作者 方正 董新涛 都磊 《电测与仪表》 北大核心 2023年第3期136-144,共9页
华东镇海-舟山500 kV线路工程采用复杂的电缆-架空线混合输电线路,发生故障时无法准确对故障位置进行定位,且现有的重合闸方案无法实现自动识别架空线路故障并投入重合闸。文章提出一种基于分布参数模型的混合线路故障测距方案。该方案... 华东镇海-舟山500 kV线路工程采用复杂的电缆-架空线混合输电线路,发生故障时无法准确对故障位置进行定位,且现有的重合闸方案无法实现自动识别架空线路故障并投入重合闸。文章提出一种基于分布参数模型的混合线路故障测距方案。该方案采用正序故障分量,利用混合线路各段准确参数,分别采用线路两侧电气量计算沿线各点的电压有效值。根据两侧电气量计算的故障位置电压有效值相等的特点,对故障位置进行准确计算。且针对实际工程对重合闸的需求,提出一种故障位置区段定位方法。该方法通过比较用两侧电气量计算的电缆和架空线交界处电压有效值,对故障所在区段进行定位,以实现故障点位于电缆线路时不重合闸,故障点在架空线时重合闸。仿真结果表明,采用华东镇海-舟山500 kV线路工程各段准确参数,各故障位置、各故障类型测距误差均不大于2.5%或±1 km,测距结果不受过渡电阻影响,且可实现自动识别架空线故障并投入重合闸。 展开更多
关键词 混合输电线路 分布参数 故障测距 自动重合闸
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The development of local ambient air quality standards: A case study of Hainan Province, China 被引量:1
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作者 Qian Song Nannan Zhang +19 位作者 Yanning Zhang Dejia Yin Jiming Hao Shuxiao Wang Shengyue Li Wenshuai Xu Weijun Yan Xinxin Meng Xinghong Xu Xiaochen Wu donghai Xie Yun Zhu Qipeng Qu Xuan Hou Yueqi Jiang Zhaoxin Dong Haotian zheng Yisheng Sun Zeqi Li Bin Zhao 《Eco-Environment & Health》 2024年第1期11-20,共10页
The ambient air quality standard(AAQS)is a vital policy instrument for protecting the environment and human health.Hainan Province is at the forefront of China's efforts to protect its ecological environment,with ... The ambient air quality standard(AAQS)is a vital policy instrument for protecting the environment and human health.Hainan Province is at the forefront of China's efforts to protect its ecological environment,with an official goal to achieve world-leading air quality by 2035.However,neither the national AAQS nor the World Health Organization guideline offers sufficient guidance for improving air quality in Hainan because Hainan has well met the former while the latter is excessively stringent.Consequently,the establishment of Hainan's local AAQS becomes imperative.Nonetheless,research regarding the development of local AAQS is scarce,especially in comparatively more polluted countries such as China.The relatively high background values and significant interannual fluctuations in air pollutant concentrations in Hainan present challenges in the development of local AAQS.Our research proposes a world-class local AAQS of Hainan Province by reviewing the AAQS in major countries or regions worldwide,analyzing the influence of different statistical forms,and carefully evaluating the attainability of the standard.In the proposed AAQS,the annual mean concentration limit for PM2.5,the annual 95th percentile of daily maximum 8-h mean(MDA8)concentration limit for O_(3),and the peak season concentration limit for O_(3) are set at 10,120,and 85μg/m^(3),respectively.Our study indicates that,with effective control policies,Hainan is projected to achieve compliance with the new standard by 2035.The implementation of the local AAQS is estimated to avoid 1,526(1,253–1,789)and 259(132–501)premature deaths attributable to longterm exposure to PM2.5 and O_(3) in Hainan in 2035,respectively. 展开更多
关键词 Local ambient air quality standard Statistical form FEASIBILITY Health effects Hainan province
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Information geography: The information revolution reshapes geography 被引量:4
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作者 Xin LI donghai zheng +1 位作者 Min FENG Fahu CHEN 《Science China Earth Sciences》 SCIE EI CSCD 2022年第2期379-382,共4页
The information revolution has been one of the driving forces to the innovation in geography. However, environmental remote sensing, geographic information science and technology, and geocomputing, which once resided ... The information revolution has been one of the driving forces to the innovation in geography. However, environmental remote sensing, geographic information science and technology, and geocomputing, which once resided within the family of geography, are gradually moving close to information science but are alienated from geography. Therefore, it is necessary to reexamine the interactive convergence of geography and information science, and advance the disciplinary system of geographic science to accommodate the researches with information as subjects and methods. In this paper, we propose to reformulate the relationship between geographic science and information science with a new discipline, i.e., information geography, which not only refers to the geography of information but also a methodological system for studying geography using information science.This paper summarizes the background of information geography’s emergence, its definition, and the difference and similarities with other disciplinary concepts. The impact of information geography on geographic paradigm shift is also investigated from the ontological, epistemological, and methodological perspectives. 展开更多
关键词 Information geography GEOGRAPHY Information revolution METHODOLOGY Geographic paradigm
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Mitochondria-targeted atovaquone promotes anti-lung cancer immunity by reshaping tumor microenvironment and enhancing energy metabolism of anti-tumor immune cells
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作者 donghai Xiong zheng Yin +5 位作者 Mofei Huang Yian Wang Micael Hardy Balaraman Kalyanaraman Stephen T Wong Ming You 《Cancer Communications》 SCIE 2024年第3期448-452,共5页
Dear Editor,Atovaquone(ATO),a mitochondrial inhibitor,has anti-cancer effects[1].Based on ATO,we developed mitochondria-targeted atovaquone(Mito-ATO)that had even stronger anti-tumor efficacy than ATO[2].We syn-thesiz... Dear Editor,Atovaquone(ATO),a mitochondrial inhibitor,has anti-cancer effects[1].Based on ATO,we developed mitochondria-targeted atovaquone(Mito-ATO)that had even stronger anti-tumor efficacy than ATO[2].We syn-thesized Mito-ATO by attaching the bulky triphenylphos-phonium(TPP)group to ATO via a ten-carbon alkyl chain(Supplementary file of methods;Supplementary Figure S1). 展开更多
关键词 metabolism IMMUNITY TARGETED
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松铺覆盖下相变黏土施工防冻控温数值模拟
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作者 刘东海 郑涵 +1 位作者 马子茹 陈辉 《水利学报》 EI CSCD 北大核心 2024年第8期955-965,共11页
堤坝及路基等工程冬季负温下施工,土料会因短时冻结或冻融而引起压实性能降低,并诱发冻胀、融沉、开裂等病害。常规覆盖保温措施工艺复杂,难以实现负温下连续施工,易使工期延长。相变黏土为改善土料防冻性能、延长冬季施工时间提供了可... 堤坝及路基等工程冬季负温下施工,土料会因短时冻结或冻融而引起压实性能降低,并诱发冻胀、融沉、开裂等病害。常规覆盖保温措施工艺复杂,难以实现负温下连续施工,易使工期延长。相变黏土为改善土料防冻性能、延长冬季施工时间提供了可能,但相变材料(PCM)掺量过高影响土料力学性能。为此,本文提出了土料掺混PCM与松铺覆盖联合的防冻控温措施,利用原有施工中上层土料松铺工序,尽可能减少PCM掺量,减小施工干扰,同时解决负温施工暴露时段土料的表层防冻问题。首先,建立了考虑上层土料松铺的施工相变传热有限元数值模型,并验证了模型的有效性;然后,定量分析了不同松铺厚度、PCM掺量对相变黏土冬季施工控温效果的影响,提出了相变黏土有效施工时长的估计方法;最后,给出了防冻控温措施建议,采用2%PCM掺量和9.6 cm松铺覆盖层厚度,即可满足现场施工控温的要求。本研究为解决寒区土料冬季施工过程中的防冻控温难题提供了新的技术途径。 展开更多
关键词 相变黏土 防冻控温 松铺覆盖 相变传热 数值模拟
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Differences in Precipitation and Related Wind Dynamics and Moisture and Heat Features in Separate Areas of the South China Sea before and after Summer Monsoon Onset
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作者 Chunyan ZHANG donghai WANG +3 位作者 Kaifeng ZHANG Wanwen HE Yanping zheng Yan XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1643-1660,共18页
Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different area... Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different areas of the South China Sea(SCS) before and after SCS summer monsoon onset(SCSSMO). The rainy sea around Dongsha(hereafter simply referred to as Dongsha) near the north coast, and the rainless sea around Xisha(hereafter simply referred to as Xisha) in the western SCS, are selected as two typical research subregions. It is found that Dongsha, rather than Xisha, has an earlier and greater increase in precipitation after SCSSMO under the combined effect of strong low-level southwesterly winds, coastal terrain blocking and lifting, and northern cold air. When the 950-h Pa southwesterly winds enhance and advance northward, accompanied by strengthened moisture flux, there is a strong convergence of wind and moisture in Dongsha due to a sudden deceleration and rear-end collision of wind by coastal terrain blocking. Moist and warm advection over Dongsha enhances early and deepens up to 200 h Pa in association with the strengthened upward motion after SCSSMO, thereby providing ample moisture and heat to form strong precipitation. However, when the 950-h Pa southwesterly winds weaken and retreat southward, Xisha is located in a wind-break area where strong convergence and upward motion centers move in. The vertical moistening and heating by advection in Xisha enhance later and appear far weaker compared to that in Dongsha, consistent with later and weaker precipitation. 展开更多
关键词 Dongsha Xisha South China Sea summer monsoon onset PRECIPITATION wind dynamics MOISTURE HEAT
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A review of integrated surface-subsurface numerical hydrological models
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作者 Lele SHU Hao CHEN +8 位作者 Xianhong MENG Yan CHANG Litang HU Wenke WANG Longcang SHU Xuan YU Christopher DUFFY Yingying YAO donghai zheng 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第5期1459-1479,共21页
Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in hydrology.These models... Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in hydrology.These models serve a dual purpose:they validate theoretical robustness and applicability via observational data and project future trends,thereby bridging the understanding and prediction of natural processes.In rapid advancements in computational methodologies and the continuous evolution of observational and experimental techniques,the development of numerical hydrological models based on physicallybased surface-subsurface process coupling have accelerated.Anchored in micro-scale conservation principles and physical equations,these models employ numerical techniques to integrate surface and subsurface hydrodynamics,thus replicating the macro-scale hydrological responses of watersheds.Numerical hydrological models have emerged as a leading and predominant trend in hydrological modeling due to their explicit representation of physical processes,heightened by their spatiotemporal resolution and reliance on interdisciplinary integration.This article focuses on the theoretical foundation of surface-subsurface numerical hydrological models.It includes a comparative and analytical discussion of leading numerical hydrological models,encompassing model architecture,numerical solution strategies,spatial representation,and coupling algorithms.Additionally,this paper contrasts these models with traditional hydrological models,thereby delineating the relative merits,drawbacks,and future directions of numerical hydrological modeling. 展开更多
关键词 Numerical Hydrological Models Surface-Subsurface Process Coupling Numerical Methods Hydrological Modeling
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X射线荧光光谱法测定液体化妆品中铅、砷和浴盐中氯的含量 被引量:3
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作者 杨乐萍 翁东海 +4 位作者 许佳明 高佳男 郑琳 任飞 王谦 《理化检验(化学分册)》 CAS CSCD 北大核心 2018年第4期383-387,共5页
用聚焦式X射线荧光光谱仪测定液体化妆品中的铅、砷,以及浴盐中氯的含量,并提出了一种新的进样方法——瓶口贴膜法。对液体样品可直接进样分析,对一些固体样品,如浴盐,需经灼烧灰化后以1∶5的质量比溶于水中再行测定。方法中选用体积为2... 用聚焦式X射线荧光光谱仪测定液体化妆品中的铅、砷,以及浴盐中氯的含量,并提出了一种新的进样方法——瓶口贴膜法。对液体样品可直接进样分析,对一些固体样品,如浴盐,需经灼烧灰化后以1∶5的质量比溶于水中再行测定。方法中选用体积为2mL,且其瓶口高度误差在0.2mm以内,具有带孔瓶盖的小瓶作为进样瓶。将液体样品装入瓶中,使液面略超瓶口,随即将2.5μm聚酯(Mylar)膜覆盖于上,拧上瓶盖并使膜紧贴液面,保持平整。将进样瓶置于样品台上,移动样品台,用激光对焦,采用扩展康普顿散射模型进行基体校正和校准曲线拟合。结果表明:常量氯元素的测定值的相对标准偏差(n=11)为0.65%;痕量铅和砷的测定值的相对标准偏差(n=11)均小于5.0%,其检出限分别为3.0,1.0 mg·L^(-1)。测定结果均与标准方法测定结果相符。 展开更多
关键词 X射线荧光光谱法 聚焦 化妆品 浴盐
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Spatially Interlinked Graphene with Uniformly Loaded Sulfur for High Performance Li-S Batteries 被引量:3
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作者 donghai Liu Chen Zhang +4 位作者 Xiaohui Lv Xiaoyu zheng Lei Zhang Linjie Zhi Quan-Hong Yang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2016年第1期41-45,共5页
Lithium-sulfur (Li-S) batteries have drawn extensive attentions due to their high energy density, environmental friendliness and low cost. In this study, three-dimensional (3D) graphene/S hybrid (G/S) is prepare... Lithium-sulfur (Li-S) batteries have drawn extensive attentions due to their high energy density, environmental friendliness and low cost. In this study, three-dimensional (3D) graphene/S hybrid (G/S) is prepared by a one-pot hydrothermal method together with redox reaction between S-based compound and graphene oxide (GO). G/S has a three dimensional porous structure, where graphene is interconnected with each other forming a 3D conductive network. It demonstrates that the pore structure of G/S can be well controlled by optimizing the drying method of the 3D graphene-based materials. Freeze drying and evaporation-induced drying can induce different density and pore structure of G/S. Electrochemical tests illustrate that the resulting hybrid can deliver a specific capacity of 891 mAh·g^-1 and 575 mAh·g^-1 for the 1^st and 100^th cycle at a current density of 500 mAh·g^-1 . 展开更多
关键词 Li-S battery GRAPHENE three-dimensional graphene/S hybrid different drying methods
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Fmoc-L-Orn(Boc)-Gly-OH的合成工艺研究 被引量:1
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作者 张东海 郑征 +5 位作者 杨再宽 吴惠峰 孙梦春 曹力智 周星宇 杨大成 《合成化学》 CAS 2023年第5期383-388,共6页
N^(α)-芴甲氧羰基-N^(δ)-叔丁氧羰基-L-鸟氨酰甘氨酸(Fmoc-L-Orn(Boc)-Gly-OH)是宫缩抑制剂阿托西班的短肽片段,通过液相合成法高效合成高纯度的Fmoc-L-Orn(Boc)-Gly-OH片段可以有效降低阿托西班的合成成本。采用液相合成方法,以N-羟... N^(α)-芴甲氧羰基-N^(δ)-叔丁氧羰基-L-鸟氨酰甘氨酸(Fmoc-L-Orn(Boc)-Gly-OH)是宫缩抑制剂阿托西班的短肽片段,通过液相合成法高效合成高纯度的Fmoc-L-Orn(Boc)-Gly-OH片段可以有效降低阿托西班的合成成本。采用液相合成方法,以N-羟基-5-降冰片烯-2,3-二甲酰亚胺(HONB)活化N^(α)-芴甲氧羰基-N^(δ)-叔丁氧羰基-L-鸟氨酸(Fmoc-L-Orn(Boc)-OH)的羧基高效合成Fmoc-L-Orn(Boc)-Gly-OH,并对反应物料配比和反应溶剂体系进行了研究,得到了最优的Fmoc-L-Orn(Boc)-Gly-OH合成工艺,该工艺操作简单、成本低且产物纯度高,可用于工业化生产。 展开更多
关键词 阿托西班 Fmoc-L-Orn(Boc)-Gly-OH 多肽片段 合成工艺 液相合成
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Clinical effect of Cidan capsule on primary hepatocellular carcinoma in 325 cases
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作者 zheng Dongjing zheng donghai +4 位作者 zheng Weihong Xu Xin zheng Weida Yang Yige Yang Yiting 《World Journal of Integrated Traditional and Western Medicine》 2016年第1期7-11,共5页
OBJECTIVE: To observe the clinical effect of Cidan capsules, a traditional Chinese medicine applied as an antitumor drug for decades, on the treatment of primary hepatocellular carcinoma(HCC). A two-month experimen... OBJECTIVE: To observe the clinical effect of Cidan capsules, a traditional Chinese medicine applied as an antitumor drug for decades, on the treatment of primary hepatocellular carcinoma(HCC). A two-month experiment was carried out. METHODS: A total of 325 patients with primary HCC were randomly divided into 3 groups. The 125 patients in Group A were treated with Cidan capsules exclusively. The 100 patients in Group B were treated with Cidan capsules combined with chemotherapy. And as control group, the 100 patients in Group C were treated by chemotherapy only. The efficacy of Cidan was analyzed by monitoring associated symptoms and liver function tests and measuring the levels of the NK cell, CD3, CD4, CRJ and CD8, alpha fetoprotein(AFP). The evaluation of Cidan's effects on enhancing the patients' life quality was through clinical and pathological observations. RESULTS: The result showed that the steady rate following the standard for evaluation of Kamofsky was over 87.0% in group B, 72.0% in Group A and 57.0% in Group C, respectively. The life quality of the patients treated with Cidan capsules and chemotherapy was improved more obviously than that in Group A and C. The NK cell,CD3, CD4,CRJ and CD8 in Group C were obviously decreased, while those in Group A and Group B were without apparent vacillation. AFP descended markedly in Group A and B, but did not in Group C. CONCLUSION: Cidan capsules combined with chemotherapy had superior curative effects on primary HCC. 展开更多
关键词 primary hepatocellular carcinoma liver cancer Cidan capsules Chinese medical therapy CHEMOTHERAPY
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