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新疆和田地区兰干色日克河径流特性分析
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作者 谢源源 《人民黄河》 CAS 北大核心 2023年第S01期3-4,10,共3页
以平原河流兰干色日克河为对象,探讨南疆资料匮乏地区河流径流量组成与特性。主要以努尔水文站1962—2021年实测径流量系列及洪水调查成果,对干流径流及各源流(5条河)径流组成年内分配情况进行分析,得出较为可靠的兰干色日克河逐月径流... 以平原河流兰干色日克河为对象,探讨南疆资料匮乏地区河流径流量组成与特性。主要以努尔水文站1962—2021年实测径流量系列及洪水调查成果,对干流径流及各源流(5条河)径流组成年内分配情况进行分析,得出较为可靠的兰干色日克河逐月径流量成果,供区域水资源规划设计、管理调度参考。 展开更多
关键词 径流特性 多年平均年径流量 兰干色日克河 和田地区
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新疆库车河流域泥沙特性分析
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作者 王进 《地下水》 2023年第3期240-242,共3页
河流泥沙是水资源开发及涉河工程的建设的重要水文影响因素。为对新疆库车河流域泥沙特性进行研究,基于河流主要水量控制站兰干站近40余年水文观测资料,对库车河悬移质泥沙的含沙量、输沙量、泥沙年内和年际变化特征及河流水沙关系等特... 河流泥沙是水资源开发及涉河工程的建设的重要水文影响因素。为对新疆库车河流域泥沙特性进行研究,基于河流主要水量控制站兰干站近40余年水文观测资料,对库车河悬移质泥沙的含沙量、输沙量、泥沙年内和年际变化特征及河流水沙关系等特性进行分析,结果表明:库车河夏季冰川融雪和暴雨洪水期流速大,水量集中,水流挟沙能力大,是含沙量高峰期,含沙量与径流量变化基本一致,主要集中在汛期;泥沙输移与径流的变化关系密切,河流输沙量季节变化极大,汛期泥沙输移较多,枯水期则较少,来水条件是河流输沙量短期剧增的主要原因。分析结论以期为库车河水资源开发利用提供参考。 展开更多
关键词 推移质泥沙 兰干水文站 库车河
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互联网告别烧钱时代
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作者 蔡爱国 《观察与思考》 2002年第12期42-44,共3页
编者按:每年一届的"西湖论剑"一直是中国互联网经济领袖人物的高层峰会,今年的"西湖论剑"于11月3日在美丽的西子湖畔举行.与往年不同的是,座上高朋已不再是王峻涛或者张朝阳,代之的是QQ先生马化腾、无忧总裁甄荣辉... 编者按:每年一届的"西湖论剑"一直是中国互联网经济领袖人物的高层峰会,今年的"西湖论剑"于11月3日在美丽的西子湖畔举行.与往年不同的是,座上高朋已不再是王峻涛或者张朝阳,代之的是QQ先生马化腾、无忧总裁甄荣辉等人,议题也由"烧钱还是赚钱"转为"网络改变生活".虽然风云变幻的景象已不再,但我们似乎也看到了江湖成熟的可能.本文谨收录与会高手的部分精美"招式",以供揣摩. 展开更多
关键词 马化腾 大家 无忧 总裁 旅行社 旅游社 旅游企业 西湖论剑 软件 外汇 投资 财政管理 周鸿 兰干 银行 金融机构 美元 本位币 消费 生产关系
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Drought Resistance of Slope Pioneer Plant Magnolia multiflora 被引量:1
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作者 许翩翩 王建柱 《Agricultural Science & Technology》 CAS 2016年第9期2037-2041,2045,共6页
[Objective] This study aimed to reveal responses of Magnolia multiflora to soil drought stress. [Method] Pot experiment was employed to simulate drought stress, and photosynthetic and physiological indices of M. multi... [Objective] This study aimed to reveal responses of Magnolia multiflora to soil drought stress. [Method] Pot experiment was employed to simulate drought stress, and photosynthetic and physiological indices of M. multiflora were determined. [Result] The net photosynthetic rate (Pn) of M. multiflora did not change significantly under mild drought stress, and reduced significantly under moderate and severe drought stress. Drought stress reduced stomatal conductance (Gs), transpiration rate (Tr) and intercellular CO2 concentration (Ci), and compared with those in the control group, the Pn, Gs, Tr and Ci under severe drought stress declined by 61.04%, 86.27%, 87.77% and 42.63%, respectively. The malondialdehyde (MDA) content in M. multiflora leaves did not increase significantly under mild drought stress, and increased significantly under moderate and severe drought stress. The MDA content in M. multiflora leaves under severe drought stress was 1.63 times as high as that in the control group. The proline (Pro) and soluble sugar contents of M. multiflora increased significantly with the aggravation of drought stress, and those under severe drought stress were 8.06 times and 3.16 times respectively higher than those in the control group. [Conclusion] M. multiflora has a strong drought tolerance, and is suitable for growing in relatively arid environment. It can be used as candidate for vegetation restoration in hydropower engineering slope. 展开更多
关键词 Hydropower engineering Drought stress Magnolia multiflora Photosynthetic characteristics Physiological characteristics
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Regional Atmospheric Blocking in the Drought Periods in Ukraine
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作者 Inna G. Semenova 《Journal of Earth Science and Engineering》 2013年第5期341-348,共8页
The conditions for regional circulation of the atmosphere in the periods of severe droughts in Ukraine are described by two circulation indexes. In analogy with experimental index EBI (European Blocking Index) for t... The conditions for regional circulation of the atmosphere in the periods of severe droughts in Ukraine are described by two circulation indexes. In analogy with experimental index EBI (European Blocking Index) for the Eastern Atlantic and Western Europe is proposed a new index ECBI (European Continental Blocking Index), which describes the blocking of zonal flow over the European continent. The obtained time series of the ECBI for the spring-summer seasons with the severe droughts in Ukraine were analyzed. Katz circulation index was used for the estimating of intensity of the meridional atmospheric processes during the same droughts. It is shown that there registered a high frequency of blocking processes which was accompanied by positive phases of ECBI and an increase in the meridional component of an atmospheric flow over the region of Europe. In years with droughts in average 60% consecutive pentads were with a positive value of ECBI, mostly in April to May. The absolute maximum duration of blocking was the 10 consecutive pentads and observed in 1963. The high positive values of the ECBI and Katz index were connected with strong anomalies in seasonal and monthly fields of wind over territory of Eastern Europe. A close relationship between the ECBI and the Katz index was obtained, which allowed to determine the critical value of the Katz index for the beginning of blocking situation, 展开更多
关键词 Atmospheric blocking blocking index circulation index drought.
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对“阑干”一词注解的探究
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作者 郭天成 《课外阅读(中下)》 2012年第20期283-283,共1页
“瀚海阑干百丈冰,愁云惨淡万里凝”是盛唐边塞诗人岑参《白雪歌送武判官归京》中的名句,即写西域严冬气候之恶劣,征人之艰苦。人教版八年级语文下册作注解时,将“阑干”解释为“纵横”,笔者认为实属不妥,很有商榷的必要。
关键词 阑干 兰干 纵横 驿站
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Preparation and stability study of lansoprazole for injection
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作者 Zhenyu Lu Rong Xu +2 位作者 Wei Dai Jing Lin Chen Shen 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2018年第6期442-450,共9页
In the present study, we aimed to assess the preparation method of sterile lansoprazole powder for injection, as well as its quality and stability. By cryodesiccation technology in combination with the control of its ... In the present study, we aimed to assess the preparation method of sterile lansoprazole powder for injection, as well as its quality and stability. By cryodesiccation technology in combination with the control of its quality and stability, the optimal formulation and preparation route were screened. Through small-scale and pilot-scale production validation, the formulation and preparation route were confirmed, in which mannitol was used as skeletal matter, meglumine was used as solubilizer and p H stabilizer, and sodium hydroxide was used as p H regulator. The formulation and preparation route were reasonable, showing good quality control and stability and fitting the pharmaceutical and clinical need. 展开更多
关键词 LANSOPRAZOLE FREEZE-DRYING Preparation route Stability study
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Impact of Land-Use Change on Soil Microbial Community Composition and Organic Carbon Content in the Dry Tropics 被引量:5
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作者 Chandra Mohan KUMAR Nandita GHOSHAL 《Pedosphere》 SCIE CAS CSCD 2017年第5期974-977,共4页
Restoration of forests poses a major challenge globally, particularly in the tropics, as the forests in these regions are more vulnerable to land-use change. We studied land-use change from natural forest(NF) to degra... Restoration of forests poses a major challenge globally, particularly in the tropics, as the forests in these regions are more vulnerable to land-use change. We studied land-use change from natural forest(NF) to degraded forest(DF), and subsequently to either Jatropha curcas plantation(JP) or agroecosystem(AG), in the dry tropics of Uttar Pradesh, India, with respect to its impacts on soil microbial community composition as indicated by phospholipid fatty acid(PLFA) biomarkers and soil organic carbon(SOC) content. The trend of bacterial PLFAs across all land-use types was in the order: NF > JP > DF> AG. In NF, there was dominance of gram-negative bacterial(G^-) PLFAs over the corresponding gram-positive bacterial(G^+) PLFAs. The levels of G^- PLFAs in AG and JP differed significantly from those in DF, whereas those of G^+ PLFAs were relatively similar in these three land-use types. Fungal PLFAs,however, followed a different trend: NF > JP > DF = AG. Total PLFAs, fungal/bacterial(F/B) PLFA ratio, and SOC content followed trends similar to that of bacterial PLFAs. Across all land-use types, there were strong positive relationships between SOC content and G-, bacterial, fungal, and total microbial PLFAs and F/B PLFA ratio. Compared with bacterial PLFAs, fungal PLFAs appeared to be more responsive to land-use change. The F/B PLFA ratio, fungal PLFAs, and bacterial PLFAs explained 91%, 94%,and 73% of the variability in SOC content, respectively. The higher F/B PLFA ratio in JP favored more soil C storage, leading to faster ecosystem recovery compared to either AG or DF. The F/B PLFA ratio could be used as an early indicator of ecosystem recovery in response to disturbance, particularly in relation to land-use change. 展开更多
关键词 ecosystem recovery fungal/bacterial ratio natural forest phospholipid fatty acid (PLFA) PLANTATION
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Drought effects on the plasticity in vessel traits of two endemic Magnolia species in the tropical montane cloud forests of eastern Mexico
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作者 Ernesto Chanes Rodríguez-Ramírez José Antonio Vázquez-García +2 位作者 Ignacio García-González Othón Alcántara-Ayala Isolda Luna-Vega 《Journal of Plant Ecology》 SCIE CSCD 2020年第3期331-340,共10页
Aims We aimed to evaluate how climatic fluctuations influence the plasticity of anatomical vessel traits and the width of annual tree-rings of two relict-endemic Mexican Magnolia species.Notwithstanding,few studies ha... Aims We aimed to evaluate how climatic fluctuations influence the plasticity of anatomical vessel traits and the width of annual tree-rings of two relict-endemic Mexican Magnolia species.Notwithstanding,few studies have assessed the drought effect on vessel traits in tropical montane cloud trees of eastern Mexico.Methods Through digital images of growth rings,we assessed the tree radial growth rate,age of the trees and plasticity in vessel traits regarding climatic fluctuations of the Mexican Magnolia species studied.We compared vessel density,hydraulic diameter and percentage of conductive area in drought years(DY)and non-drought years(NDY)in two Mexican Magnolia species.Important Findings For the first time,the plasticity that occurs in porous wood vessel traits to long-term climatic fluctuations was analysed for two endangered Magnolia species(Magnolia vovidesii and M.schiedeana)from two tropical montane cloud forests in Mexico.We found that temperature and precipitation were strongly associated with differences in tree-ring width when DY and NDY were compared.Our analyses revealed that a high plasticity in vessel anatomy of diffuse-porous wood was related to temperature and/or water availability for both Magnolia species studied.We concluded that anatomical adaptations to DY resulted in a substantial reduction in vessel traits when compared with NDY,and that the plastic adaptations played an essential role in water transport and safety for the survival of the studied species during stressful long periods. 展开更多
关键词 ADAPTABILITY climate variability drought–growth relationship Magnolia schiedeana Magnolia vovidesii quantitative wood anatomy
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