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Characteristics of Water Type Distribution and Seasonal Variations in the Southern East China Sea
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作者 Miao Yutian, Yu Honghua, He Dehua and Wang Chunsheng Second Institute of Oceanography, SOA , Hangzhou 310012 《Marine Science Bulletin》 CAS 1999年第1期11-24,共14页
By using the data of Summer and Winter 1987, Spring and Autumn 1988 obtained by the R/V " Shijian" during the China-Japan Joint Research Program on Kuroshio, the paper makes an analysis and research on the w... By using the data of Summer and Winter 1987, Spring and Autumn 1988 obtained by the R/V " Shijian" during the China-Japan Joint Research Program on Kuroshio, the paper makes an analysis and research on the water type distribution and its variations in the studied sea area. Trie results of which are mainly as follows: (1) The Class IV mixing water whose property is similar to that of the continental coastal water is located in the northeast sea area, along the coast of the continent in autumn and winter while extending to the open sea in spring and summer. (2) The boundary between the Kuroshio water and the shelf mixing water (called the left boundary of the Kroshio water) is approximately located in between the 100m and 200m isobaths in various seasons and various layers, and mostly near the 200m isobath. In the sea area northeast of Taiwan, the Kuroshio water is to the west most in spring and then in winter. In summer, it is to the east most while, in autumn, it is in between its positions in summer 展开更多
关键词 SOUTHERN East China Sea water type DISTRIBUTION SEASONAL variation
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Response of soil water dynamics to precipitation years under different vegetation types on the northern Loess Plateau, China 被引量:15
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作者 LIU Bingxia SHAO Ming'an 《Journal of Arid Land》 SCIE CSCD 2016年第1期47-59,共13页
Implementation of the Grain-for-Green project has led to rapid land cover changes and resulted in a significantly increased vegetation cover on the Loess Plateau of China during the past few decades. The main objectiv... Implementation of the Grain-for-Green project has led to rapid land cover changes and resulted in a significantly increased vegetation cover on the Loess Plateau of China during the past few decades. The main objective of this study was to examine the responses of soil water dynamics under four typical vegetation types against precipitation years. Soil water contents (SWCs) were measured in 0–4.0 m profiles on a hillslope under the four vegetation types of shrub, pasture, natural fallow and crop in a re-vegetated catchment area from April to October in normal (2010), dry (2011), wet (2014) and extremely wet (2013) years. The results indicated that precipitation and vegetation types jointly controlled the soil water temporal dynamics and profile characteristics in the study region. SWCs in 0–4.0 m profiles of the four vegetation types were ranked from high to low as crop>fallow>pasture>shrub and this pattern displayed a temporal stability over the four years. In the extremely wet year, SWC changes occurred in the 0–2.0 m layer under shrub and pasture while the changes further extended to the depth of 4.0-m deep layers under fallow and crop. In the other three years, SWCs changes mainly occurred in the 0–1.0 m layer and kept relatively stable in the layers deeper than 1.0 m for all the four vegetation types. The interannual variation in soil depth of SWCs was about 0–2.0 m for shrub and pasture, about 0–3.4 m for fallow and about 0–4.0 m for crop, respectively. The dried soil layers formed at the depths of 1.0, 0.6, 1.6 and 0.7 m under shrub, and 1.0, 1.0, 2.0 and 0.9 m under pasture, respectively in 2010, 2011, 2013 and 2014. The infiltrated rainwater mostly stayed in the 0–1.0 m layer and hardly supplied to soil depth >1.0 m in normal, dry and wet years. Even in the extremely wet year of 2013, rainwater recharge depth did not exceed 2.0 m under shrub and pasture. This implied that soil desiccation was difficult to remove in normal, dry and wet years, and soil desiccation could be removed in 1.0–2.0 m soil layers even in the extremely wet year under shrub and pasture. The results indicated that the natural fallow was the best vegetation type for achieving sustainable utilization of soil water and preventing soil desiccation. 展开更多
关键词 precipitation pattern RESTORATION soil water dynamics soil desiccation vegetation type
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Type of major water hazards and study of countermeasures in Shennan Mining Area
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作者 WANG Hong-ke GUO Jiao SHI Ying-chun 《Journal of Groundwater Science and Engineering》 2015年第1期70-76,共7页
By analysing the hydrogeological conditions of this region and the coal mines hereof, together with the water hazards troubled Shennan mine area in recent years, this paper summarized six types of mine water hazards. ... By analysing the hydrogeological conditions of this region and the coal mines hereof, together with the water hazards troubled Shennan mine area in recent years, this paper summarized six types of mine water hazards. As per the basic characteristics, geological distribution, threat degree and difficulty of prevention of various water hazards, along with the practice of water prevention in the mining area, this article proposed effective technical measures for the prevention and control of different water hazards and laid a solid foundation for the safe production in the mining area. 展开更多
关键词 Shennan Mining Area Hydrogeological conditions type of water hazard Characteristics of water hazards COUNTERMEASURES
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The Influence of Lithostratigraphy on the Type and Quality of Stored Water in Mujib Reservoir-Jordan
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作者 Habes Mohammad Al-Mashakbeh 《Journal of Environmental Protection》 2017年第4期568-590,共23页
This study was carried out to investigate the impact of drainage basin’s lithostratigraphy on the quality and type of stored water in the Mujib dam reservoir. The water samples were collected on a monthly basis from ... This study was carried out to investigate the impact of drainage basin’s lithostratigraphy on the quality and type of stored water in the Mujib dam reservoir. The water samples were collected on a monthly basis from surface water from January 2012 to December 2015. The classifications of collecting water samples for domestic and irrigation purposes were based on different physico- chemical parameters such as pH, EC, TDS, TSS, Na+, K+, Ca2+, Mg2+, Cl-, SO42-, HCO3- , NH4+, NO3- , NO2- , SAR, RSC, SSP, RSBC, PI, MAR, KR, and TH. All analyzed water samples were satisfied the Jordanian permissible limit and graded as “fresh water”. The hydrochemical indices (Mg/Ca and Cl/HCO3) and Cation Exchange values (CEV), indicating that the surface water chemistry is due to the rock weathering minerals with respect to their inland origin. The water samples have complied within the respective limits in respect of pH, EC, SAR, RSC, RSBC, MAR, KR, SSP and PI, and hard in respect of TH which may be due to the dissolution of the weathered rocks. Abundance of cations and anions is in the following order: Ca > Na > Mg > K and HCO3 > SO4 > Cl > NO3 during the period 2013-2015 and SO4 > HCO3 > Cl > NO3 through 2012. Thus, calcium and bicarbonate–sulfate are the dominant ions present in the surface water of this study. Piper diagram suggested that carbonate and gypsum weathering is the dominant process controlling reservoir water chemistry in the basin area. The quality and type of surface water can be modified by the lithology of the catchment area. The hydrogeochemical study of Mujib reservoir water indicated that the water quality is safe for drinking and agricultural purposes. 展开更多
关键词 water type water QUALITY Drinking-Irrigating water Hydrogeochemical In-dices LITHOSTRATIGRAPHY Mujib Dam RESERVOIR
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Pore-Throat Combination Types and Gas-Water Relative Permeability Responses of Tight Gas Sandstone Reservoirs in the Zizhou Area of East Ordos Basin, China 被引量:7
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作者 LI Mi GUO Yinghai +2 位作者 LI Zhuangfu WANG Huaichang ZHANG Jingxia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期622-636,共15页
With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat comb... With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat combination types in sandstones were revealed and confirmed to play a controlling role in the distribution of throat size and the characteristics of gas-water relative permeability.The type-I sandstones are dominated by intercrystalline micropores connected by cluster throats,of which the distribution curves of throat size are narrow and have a strong single peak(peak ratio>30%).The pores in the type-II sandstones dominantly consist of secondary dissolution pores and intercrystalline micropores,and throats mainly occur as slice-shaped throats along cleavages between rigid grain margins and cluster throats in clay cement.The distribution curves of throat size for the type-II sandstones show a bimodal distribution with a substantial low-value region between the peaks(peak ratio<15%).Primary intergranular pores and secondary intergranular pores are mainly found in type-III samples,which are connected by various throats.The throat size distribution curves of type-III sandstones show a nearly normal distribution with low kurtosis(peak ratio<10%),and the micro-scale throat radii(>0.5μm)constitute a large proportion.From type-I to type-III sandstones,the irreducible water saturation(Swo)decreased;furthermore,the slope of the curves of Krw/Krg in two-phase saturation zone decreased and the two-phase saturation zone increased,indicating that the gas relative flow ability increased.Variations of the permeability exist in sandstones with different porethroat combination types,which indicate the type-III sandstones are better reservoirs,followed by type-II sandstones and type-I sandstones.As an important factor affecting the reservoir quality,the pore-throat combination type in sandstones is the cumulative expression of lithology and diagenetic modifications with strong heterogeneity. 展开更多
关键词 tight gas sandstone pore-throat COMBINATION type THROAT characteristic GAS-water relative permeability Zizhou area ORDOS Basin
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Keggin type heteropolyacids-catalyzed synthesis of quinoxaline derivatives in water 被引量:4
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作者 Tai Kun Huang Lin Shi Rui Wang Xing Zhou Guo Xiao Xia Lu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期161-164,共4页
Keggin type heteropolyacids was found to be an efficient and reusable catalyst for the synthesis of biologically active quinoxaline derivatives from the condensation of 1,2-diamine with 1,2-dicarbonyl compounds in exc... Keggin type heteropolyacids was found to be an efficient and reusable catalyst for the synthesis of biologically active quinoxaline derivatives from the condensation of 1,2-diamine with 1,2-dicarbonyl compounds in excellent yields in water. This method provides a new and efficient protocol in terms of small quantity of catalyst, a wide scope of substrates, and simple work-up procedure. 展开更多
关键词 Keggin type heteropolyacids 1 2-Diamines 1 2-Diketones Quinoxaline derivatives water
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Effectiveness of Alkali Water Consumption to Reduce Blood Sugar Levels in Diabetes Mellitus Type 2
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作者 Edy Siswantoro Nasrul Hadi Purwanto Sutomo   《Journal of Diabetes Mellitus》 2017年第4期249-264,共16页
Background: Non-Communicable Diseases (NCDs) have become a public health problem, globally, regionally, nationally and locally. Non-Communicable Diseases (NCDs) that took a lot of attention was diabetes mellitus. In I... Background: Non-Communicable Diseases (NCDs) have become a public health problem, globally, regionally, nationally and locally. Non-Communicable Diseases (NCDs) that took a lot of attention was diabetes mellitus. In Indonesia diabetes mellitus is a serious threat to health development. Efforts developed to overcome the problems of diabetes mellitus type 2 is to apply four pillars of therapy namely education, nutrition therapy, physical activity and pharmacology. However, these efforts have not been able to achieve optimal results due to many obstacles encountered. One of the non-pharmacological treatments that can be utilized is to consume alkaline water to reduce blood sugar levels in diabetes mellitus type 2. Methods: The research design used was quasy experiment with pre-post control group design approach. The variables observed in this study were random blood sugar changes in people with diabetes mellitus type 2 prior to intervention and after intervention. Intervention is given over a period of 14 days. To measure the demand of drinking water on the respondents, the measurement was done using Water Drink Reminder - Hydro application. The alkaline water used in this study is alkaline water produced from Kangen Water Type SD501 Platinum Machine. Test analysis used is paired t test to determine the effectiveness of alkaline water consumption to decrease random blood sugar level of diabetes mellitus type 2. To know the difference of effectiveness of alkaline water consumption to decrease of blood sugar level, it uses one way anova test with significance value α: 0.05. Results: From result of the one way anova test with significance value α: 0.05, we have got significance 0.039. Since the significance probability value is 0.039 0.05, the research hypothesis is accepted which means that there is a significant difference in the level of random blood sugar of diabetes mellitus type 2 performed by using four kinds of intervention of alkaline water treatment (Alkali Water PH 7.0, PH 8.0, PH 9.5 and PH 9.5 and PH 11.5) for a period of 14 days. Conclusion: Support from health personnel and adherence to diabetes mellitus is required to utilize alkaline water as nonpharmacologic therapy to control blood sugar levels in people with type 2 diabetes mellitus. To achieve maximum results from nonfarmakologi therapy performed, people with diabetes mellitus type 2 should routinely consume antidiabetic drugs provided by health personnel and always strive for a healthy life. 展开更多
关键词 DIABETES MELLITUS type 2 Nonpharmacology Therapy ALKALINE water
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Study of amplification coefficient in a water-cooling Gardon-type heat power measuring apparatus 被引量:1
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作者 Li Miao Li Yunze +3 位作者 Zhang Hongsheng Wang Shengnan Li Yunhua Liu Jia 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第2期410-417,共8页
A new water-cooling Gardon-type heat power measuring apparatus is designed to meet the need of heat power source management and distribution. The steady state measurement mathe- matic model of the apparatus is built u... A new water-cooling Gardon-type heat power measuring apparatus is designed to meet the need of heat power source management and distribution. The steady state measurement mathe- matic model of the apparatus is built up in theory and the system amplification coefficient is defined as the ratio of the heat power to the temperature difference of the device, with which the value of the measured source power can be calculated easily with the corresponding temperature difference. In order to obtain an optimal heat power measuring system, the coefficients that can influence the relationship between the amplification coefficient, the temperature difference, and the heat power are analyzed. On the basis of these analyses, a set of experimental device is constructed and a num- ber of experiments are carried on. Compared with the input heat power sample data, the error of the experimental measuring results is less than 4-2%, and the experimental measuring values are in good agreement with the calculated theoretical ones. The heat power measuring apparatus can be applied in heat flux or heat power measurement in other fields due to its simple structure and high accuracy. 展开更多
关键词 Amplification coefficient Gardon-type Heat flux Heat power Measuring apparatus water-cooling
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延长油田靖边东部地区长2储层水化学场特征与油藏成因研究
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作者 黄天坤 雷俊杰 +5 位作者 张海 王记江 张玉琦 赵晨云 杨桂林 王大峰 《地下水》 2026年第1期5-9,共5页
延长油田靖边东部油区为一开发老区,主力产层为长2地层,目前对储层油田水性质和分布规律认识还不够充分。研究表明,区内主要分布CaCl_(2)型和NaHCO_(3)型两类水型,它们具有较好的分区聚类性。根据水型与矿化度双重指标的分区聚类叠合特... 延长油田靖边东部油区为一开发老区,主力产层为长2地层,目前对储层油田水性质和分布规律认识还不够充分。研究表明,区内主要分布CaCl_(2)型和NaHCO_(3)型两类水型,它们具有较好的分区聚类性。根据水型与矿化度双重指标的分区聚类叠合特征将四个自然区划分为7个水化学场,其中4个场为CaCl_(2)型水化学场,3个场为NaHCO_(3)型水化学场。建立了油田水地球化学指标与油藏成因关系定量表征数学模型,将13项水性定量指标相关联,利用加权层次分析法得出本区长2储层7个水化学场表现出次生油藏、半开启型油藏、封闭型油藏和破坏性油藏4种类型。同时,区内纵贯南北分布着一条矿化度(TDS)异常低值线,该TDS异常低值线可能是由断层或古河道沉积发育出的渗透带引起的,水化学场的分布规律和油藏的圈闭状态有可能受TDS异常低值线控制。本研究建立了利用水性指标判定油藏成因和封闭状态的数学模型,对储层地质认识和油田高效开发具有重要指导意义。 展开更多
关键词 水型与矿化度 油田水地球化学指标 水化学场 油藏成因 油藏封闭状态
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基于山地可移动式水肥一体控制系统首部设计
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作者 唐晨光 张瑞金 易辉君 《农业与技术》 2026年第1期66-70,共5页
农业用水量占我国淡水资源总量的80%左右,而其中的灌溉用水90%~95%的农业用水主要用于农田、果园。我国地形地貌丰富,全国位于6°以上坡度的耕地约0.29亿hm 2,占全国耕地总面积的22.74%。我国地形复杂多变,传统的水肥一体已不能满... 农业用水量占我国淡水资源总量的80%左右,而其中的灌溉用水90%~95%的农业用水主要用于农田、果园。我国地形地貌丰富,全国位于6°以上坡度的耕地约0.29亿hm 2,占全国耕地总面积的22.74%。我国地形复杂多变,传统的水肥一体已不能满足现在的生产方式,同时固定式灌溉施肥设备建设要求高,成本也高,很大程度上限制了我国农业的可持续发展。山地可移动式水肥一体首部系统设计有高集成快速交付、机动性重复利用、智慧化便捷运维、解决农业用地问题、美观设计与自然环境结合等主要优势。 展开更多
关键词 可移动式 水肥一体 山地 首部
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Effect of Pipe Diameter on Electrochemical Behavior of Stainless Steel Type 304 Pipes in Tap Water 被引量:1
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作者 Noriyuki Tanaka Shigeru Sato +4 位作者 Itaru Ikeda Tadahiko Uchida Motoki Kuratani Yutaka Yamada Osamu Sakurada 《Materials Sciences and Applications》 2019年第11期697-708,共12页
We investigated the effects of pipe diameter on the corrosion resistance of stainless steel type 304 pipes using electrochemical measurements. Compared to plate steel, pipes have harder physical properties and tend to... We investigated the effects of pipe diameter on the corrosion resistance of stainless steel type 304 pipes using electrochemical measurements. Compared to plate steel, pipes have harder physical properties and tend to be harder and showed greater permeability with decreasing inner diameter. We found that the maximum corrosion current density in the secondary active state, which is the starting point of secondary passivation, appeared in the polarization curve measurement in tap water. Similar to the Vickers hardness and the maximum current density in the secondary active state, the permeability tended to increase as the diameter decreased. This is thought to increase the amount of deformation-induced martensitic and increase corrosion susceptibility. The peak of the secondary active current density was clearly seen as the potential sweep speed was increased. In addition, potential sweep speed dependence was observed in the corrosion susceptibility evaluation of deformation-induced martensite. In comparison with acid treatment, the formation of deformation-induced martensite was considered to occur in the extreme surface layer. The maximum corrosion current density in the secondary active state is expected to be a new susceptibility evaluation method for evaluating the deformation-induced martensitic transformation. 展开更多
关键词 STAINLESS Steel type 304 ELECTROCHEMICAL CONSIDERATION Pipe Diameter ELECTROCHEMICAL Behavior TAP water
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库车山前超深裂缝性致密砂岩边水气藏试井特征分析
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作者 孙贺东 朱松柏 +4 位作者 唐永亮 王小培 闫炳旭 雷享和 魏鹏 《天然气勘探与开发》 2026年第1期63-70,共8页
塔里木盆地库车山前气田群由一系列超深层裂缝性致密砂岩边水气藏组成,基质—裂缝—断层多尺度离散裂缝发育,其试井解释极具挑战性。为了实现对该气田群储层动态特征的准确描述,基于实际测试资料和试井解释的基本原理,系统分析了库车山... 塔里木盆地库车山前气田群由一系列超深层裂缝性致密砂岩边水气藏组成,基质—裂缝—断层多尺度离散裂缝发育,其试井解释极具挑战性。为了实现对该气田群储层动态特征的准确描述,基于实际测试资料和试井解释的基本原理,系统分析了库车山前裂缝性有水气藏试井曲线的特征。研究结果表明:(1)对于边部气井,压力导数的后期上翘可能是气水黏度差异形成的假边界;随着水的逐步推进,在双对数图中导数曲线整体向左上方收缩;(2)处于构造高部位的气井,其压力导数曲线后期是一条斜率介于0.5~1.0的直线;斜率大小代表裂缝缝网发育程度,裂缝缝网越复杂,斜率值越大;高部位气井出水前后导数曲线斜率发生变化,完全水淹后又恢复原状;(3)单井不同期次产量规整化试井导数曲线对比结果表明,若无边水影响,地层系数将不发生明显的变化;(4)存在基质向裂缝系统供气的现象。结论认为:(1)库车山前气田群储层基质致密,导数曲线未出现总系统径向流时,用解析试井方法不能解释渗透率、储容比等裂缝性气藏的关键参数;(2)边部气井压力导数曲线后期上翘不一定是边界特征,应结合动态、静态资料综合研判;(3)随着气田开发的推进,储层渗透率未表现出明显的应力敏感特征。 展开更多
关键词 塔里木盆地 超深层 裂缝性边水气藏 试井曲线 渗透率 储容比 应力敏感
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Assessing the vulnerability of Dutch water bodies to exotic species: A new methodology 被引量:1
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作者 R.J. LEEWIS A. GITTENBERGER 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第6期863-873,共11页
Invasive exotic (alien) species have not been taken into enough consideration concerning the European Water Framework Directive (WFD) and other European directives until recently. The Dutch ministry responsible fo... Invasive exotic (alien) species have not been taken into enough consideration concerning the European Water Framework Directive (WFD) and other European directives until recently. The Dutch ministry responsible for water management is looking for ways to establish the impacts that invasive alien species may have on specified water types. This paper concentrates on the vulnerability of such water types to the introduction of exotic species. This new approach focusses on the system where the alien species are introduced into rather than only on the alien species themselves. We propose an equation that combines threats to and in water types with effects of particular species (observed or prognosticated). Numerical values used in the formula have been found by scoring a number of properties in different water types and species, which are specified in questionnaires. The results of the calculations are given as relative vulnerability scores (scale 1-10). By testing as many as 8 water types and 13 species, we demonstrate that this method is flexible and easy to use for water managers. Our results can be translated into classes of vulner- ability, which are represented on geographical maps with colour codes to indicate different degrees of vulnerability in the different water bodies. This readily corresponds to the way countries are required to report to the European Union in the context of the WFD. The method can also be generalized using functional groups of (exotic) species instead of particular species 展开更多
关键词 Exotic species Risk analysis VULNERABILITY METHODOLOGY European water Framework Directive water types
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复方真武冲剂治疗阳虚水泛型心力衰竭临床疗效及对心室重构、炎症因子水平的影响
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作者 刘祥彪 程晓昱 +1 位作者 胡业彬 张叶祥 《安徽医药》 2026年第2期398-403,共6页
目的观察复方真武冲剂治疗阳虚水泛型心力衰竭的临床疗效,并探索其对心功能、心室重构及炎症因子水平的影响。方法选择2023年5月至2024年3月安徽中医药大学第一附属医院老年病中心心血管内科收治心力衰竭(阳虚水泛型)病人60例。采用随... 目的观察复方真武冲剂治疗阳虚水泛型心力衰竭的临床疗效,并探索其对心功能、心室重构及炎症因子水平的影响。方法选择2023年5月至2024年3月安徽中医药大学第一附属医院老年病中心心血管内科收治心力衰竭(阳虚水泛型)病人60例。采用随机数字表法分组,对照组采用正规西药治疗,观察组在对照组基础上加服复方真武冲剂,疗程均为4周。统计两组治疗前后临床疗效,评估病人6 min步行试验的距离(6-minute walk test,6MWT),检测并比较两组病人的心功能[氨基末端脑利钠肽前体(NT-proBNP)、左心室射血分数(LVEF)]、心室重构[左心室舒张期末内径(LVEDD)、左心室收缩期末内径(LVESD)]、炎症因子[C反应蛋白(CRP)、降钙素原(PCT)、白细胞介素-6(IL-6)和血清淀粉样蛋白A(SAA)]等指标。结果经治疗后观察组心功能改善总有效率为93.3%,明显高于对照组总有效率76.7%(χ^(2)=6.05,P<0.05)。两组治疗后,观察组6MWT距离增加多于对照组[(488.97±52.65)m比(455.43±43.08)m,P<0.05],观察组NT-proBNP水平较对照组下降更明显[(106.19±26.74)ng/L比(134.38±28.10)ng/L,P<0.05],观察组LVEF提高程度优于对照组[(54.10±4.29)%比(47.50±3.81)%,P<0.05],观察组LVEDD、LVESD较对照组下降更明显(P<0.05),观察组CRP、PCT、IL-6和SAA水平均较对照组下降更明显(P<0.05)。结论复方真武冲剂联合常规西较单纯西药更好地改善阳虚水泛型心力衰竭病人心脏功能,逆转心室重构,减轻炎症反应,其机制可能与其能更好地抑制心肌细胞炎症反应有关。 展开更多
关键词 心力衰竭 复方真武冲剂 阳虚水泛型 心室重构
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基于探地雷达的黑土区农田表层含水量测定研究
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作者 张于 陆海鹏 +5 位作者 朱向明 陈一民 隋跃宇 富美玲 彭伟 冉恩华 《干旱地区农业研究》 北大核心 2026年第1期260-268,共9页
为明确探地雷达振幅包络平均值法因素(average envelope amplitude,AEA)获取黑土区表层土壤含水量的有效性,探讨中心频率、土壤类型及介电常数模型等因素对该方法准确性的影响,以草甸土、暗棕壤、白浆土为研究对象,采用中心频率为250、5... 为明确探地雷达振幅包络平均值法因素(average envelope amplitude,AEA)获取黑土区表层土壤含水量的有效性,探讨中心频率、土壤类型及介电常数模型等因素对该方法准确性的影响,以草甸土、暗棕壤、白浆土为研究对象,采用中心频率为250、500 MHz的两组探地雷达,开展黑土区农田表层含水量探测试验,并与TDR测定结果进行对比分析。结果表明:(1)中心频率为500 MHz的探地雷达反演精度优于中心频率为250 MHz的探地雷达,两者的探测深度均为30 cm左右;(2)Topp模型表现优于其他3种模型,对总体土壤含水量分布预测更为准确,RMSE最低,约为0.02 cm^(3)·cm^(-3);(3)各种土壤类型下含水量反演结果均较好,其中,草甸土和暗棕壤的反演效果最佳,白浆土次之,但总体来看R^(2)均高于0.88,RMSE均小于0.035 cm^(3)·cm^(-3);(4)采用普通克里金网格构建的土壤含水量分布图能够较为准确地反映农田尺度土壤含水量的空间分布。综上可知,探地雷达振幅包络平均值法可以用于农田尺度黑土区土壤含水量分布的快速、无损监测。 展开更多
关键词 探地雷达 土壤含水量 土壤类型 介电常数模型 振幅包络平均值法 空间分布
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干旱背景下湖库型水源地水生态环境特征及调水输入影响
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作者 王文琪 王宗志 +4 位作者 白莹 谭浪 陈星宇 余符合 狄祖兴 《水利水运工程学报》 北大核心 2026年第1期82-96,共15页
为探讨极端干旱气候条件下湖库型水源地水生态环境特征及调水工程对其产生的影响,以太湖流域湖西丘陵山区典型湖库型水源地——沙河水库为例,基于统计方法和机理模型,探讨水质水生态对干旱气候和调水输入的响应特征。研究结果表明:受202... 为探讨极端干旱气候条件下湖库型水源地水生态环境特征及调水工程对其产生的影响,以太湖流域湖西丘陵山区典型湖库型水源地——沙河水库为例,基于统计方法和机理模型,探讨水质水生态对干旱气候和调水输入的响应特征。研究结果表明:受2022—2023年流域严重干旱事件影响,沙河水库水位下降对透明度和总氮指标影响较为显著,水库基本达到了中营养到轻度富营养化状态,其中叶绿素a、水温、高锰酸盐指数、总磷对藻密度影响较大;沙河水库藻类群落时空分布差异显著,且不同藻类与特定环境因子相关性差异明显,底栖动物群落构成全年均以昆虫纲生物量占据优势,不同监测点位的优势物种也有差异。底栖生物总量与物理参数和光照条件呈正相关,而底栖生物多样性则与营养负荷呈正相关;现状补水前后水库水质高锰酸盐指数和总氮浓度短期有一定升高,逐渐趋于稳定状态。基于PCLake+模型模拟显示,不同类别水质输入影响下,叶绿素a相较于总氮、总磷受到外界扰动的响应相对迟缓,且影响随着补水结束和自我调节逐渐减弱。干旱气候对湖库水生态环境影响较大,体现在关键水质指标、藻类及底栖生物群落结构的变化,在此背景下调水输入作为一种缓解干旱的重要手段,其调水规模、时机等因素变化对湖库功能的长期效应需引起重视,库区水生态环境对调水水质的响应速度及自我调节机制也是今后亟待研究的重要课题。 展开更多
关键词 湖库型水源地 干旱影响 调水输入 水质 水生态 PCLake+模型
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地铁站台板下空间的迷宫式水蓄冷研究
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作者 谢源源 罗燕萍 +2 位作者 王静伟 张文武 许雄文 《制冷学报》 北大核心 2026年第1期147-154,共8页
空调蓄冷技术是实现“削峰填谷”的重要措施,本文提出利用地铁站台板下空间制作迷宫式蓄冷水池的水蓄冷方案。为研究该方案的可行性,首先根据雷诺数相似准则对原模型设计缩尺模型实验,并采用不同湍流模型进行蓄冷水池释冷与蓄冷过程的... 空调蓄冷技术是实现“削峰填谷”的重要措施,本文提出利用地铁站台板下空间制作迷宫式蓄冷水池的水蓄冷方案。为研究该方案的可行性,首先根据雷诺数相似准则对原模型设计缩尺模型实验,并采用不同湍流模型进行蓄冷水池释冷与蓄冷过程的数值模拟,对比实验与数值模拟结果表明:该类迷宫式蓄冷水池混合流的湍流模型采用大涡模型更为准确。在此基础上,数值模拟结果表明:地铁站台板下空间采用迷宫式水蓄冷的蓄冷与释冷的恒温层体积比约为60%。 展开更多
关键词 地铁空调 迷宫式水蓄冷 湍流模型 模型实验
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Origin and Classification of Geothermal Water from Guanzhong Basin,NW China:Geochemical and Isotopic Approach 被引量:5
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作者 Zhiyuan Ma Xiucheng Li +4 位作者 Huiju Zheng Jingbin Li Bei Pei Sen Guo Xuelian Zhang 《Journal of Earth Science》 SCIE CAS CSCD 2017年第4期719-728,共10页
Combined with tectonic evolution, a multi-isotopic method (δD, δ^18O, ^87Sr/^86Sr and ^14C) and hydrochemistry data have been used to study the origin and classification of geothermal water in the Guanzhong Basin.... Combined with tectonic evolution, a multi-isotopic method (δD, δ^18O, ^87Sr/^86Sr and ^14C) and hydrochemistry data have been used to study the origin and classification of geothermal water in the Guanzhong Basin. The study shows that geothermal water of Xianli terrace primarily came from north- west direction when accepting recharge. A small amount supply source of geothermal water in Xi'an City is from Qinling Mountain and the principal supply source comes from the west direction, but geothermal water of Chang'an District mainly accepts supply from Qinling Mountain. Based on geothermal environ- ment is open or not, the degree of water-rock interaction, and the origin of geothermal water, geothermal water of the study area can be divided into four types: A, geothermal water of Gushi depression, perfect closed thermal environment and significant water-rock interaction, belonged to residual sedimentary wa- ter origin; B, geothermal water of Xianyang City, good closed environment and relatively significant water-rock interaction, belonged to residual sedimentary water origin mixed with fossil leaching water; C, geothermal water of Xi'an City, half closed environment and some water-rock interaction, belonged to fossil leaching water origin; D, geothermal water of Chang'an District, open environment and mixed with modern precipitation, belonged to fossil leaching water origin. 展开更多
关键词 geothermal waters isotope and geochemistry classification groundwater type.
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“三北”工程区植被水分利用效率的时空变化特征
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作者 郑群芳 庞建壮 +5 位作者 张祎帆 吴小云 张勤 许行 许杨 张志强 《林业科学》 北大核心 2026年第2期75-84,共10页
【目的】探究“三北”工程区植被水分利用效率(WUE)的时空变化特征及其对环境因素和干旱事件的响应,为区域生态系统的可持续管理和干旱应对策略提供科学依据。【方法】基于2001—2022年植被总初级生产力(GPP)和蒸散(ET)数据,结合气象观... 【目的】探究“三北”工程区植被水分利用效率(WUE)的时空变化特征及其对环境因素和干旱事件的响应,为区域生态系统的可持续管理和干旱应对策略提供科学依据。【方法】基于2001—2022年植被总初级生产力(GPP)和蒸散(ET)数据,结合气象观测数据,在500 m分辨率上计算逐像元的WUE(WUE=GPP/ET),分析研究区WUE和标准化降水蒸散指数(SPEI-12,指各年份1月至12月的累积干旱程度)的时空变化特征。通过偏相关分析,探讨WUE与主要环境因素(气温、降水)和干旱之间的关系,并进一步分析不同植被类型WUE对干旱强度的响应。【结果】1)2001—2022年,“三北”工程区年平均WUE为(1.12±0.35)g·kg^(-1)。从空间分布来看,西北荒漠大部分地区(新疆南部除外)、黄土高原丘陵沟壑区和东北华北平原农区中部的WUE显著上升;新疆南部、风沙区和东北华北平原农区北部的WUE显著下降(P<0.05)。2)“三北”工程区植被WUE对降水和气温的响应存在显著空间差异,西北荒漠区、黄土高原丘陵沟壑区和风沙区大部分区域以及东北华北平原农区中部的WUE主要受降水变化的影响;新疆准噶尔盆地和塔里木盆地周边、黄土高原丘陵沟壑区中部、浑善达克和呼伦贝尔沙地以及东北华北平原农区南部的WUE主要受气温变化的影响。3)湿润地区植被WUE随干旱加剧而增加,干旱地区则相反。不同植被类型WUE对干旱的响应也表现出明显差异,森林和草地WUE在轻度和中度干旱条件下显著增加,在重度和极端干旱条件下显著下降,且草地敏感性较低,灌木WUE在轻度干旱条件下显著增加,在中度和重度干旱条件下显著下降。【结论】“三北”工程区植被WUE呈自东向西逐渐降低的空间分布特征。在湿润地区,植被WUE随干旱加剧而增加;不同植被类型WUE对环境变化和干旱的响应策略存在显著差异,草地对干旱尤为敏感。有必要根据不同区域特点的自然条件与植被特征,因地制宜地制定精准管理策略。 展开更多
关键词 水分利用效率 植被类型 干旱 “三北”工程区
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类N型长距离输水系统双向调压塔和调流阀的联合防护研究
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作者 李明珍 周建旭 《水电能源科学》 北大核心 2026年第2期129-133,共5页
类N型长距离加压输水系统的管线进口侧为布置高点,且出口侧存在局部低点,需要在避免管道漏空的前提下实现有效的水锤防护。提出了双向调压塔联合末端调流阀关闭的水锤防护措施,并且基于此建立了输水系统水力过渡过程计算分析模型,开展... 类N型长距离加压输水系统的管线进口侧为布置高点,且出口侧存在局部低点,需要在避免管道漏空的前提下实现有效的水锤防护。提出了双向调压塔联合末端调流阀关闭的水锤防护措施,并且基于此建立了输水系统水力过渡过程计算分析模型,开展了双向调压塔体型参数和调流阀关闭规律的优化分析,进一步阐明了调流阀不同的关闭策略对系统水锤防护效果的影响。结果表明,联合高点设置双向调压塔与管线末端调流阀依规律关闭,调流阀采用优化的先快后慢折线关闭规律,与水泵出口阀同步关闭和滞后关闭,均能够有效实现水锤防护;考虑到调流阀的远程控制方式,适当增大双向调压塔的设置面积,调流阀可以采用更为灵活的滞后关闭策略。 展开更多
关键词 类N型输水系统 水锤防护 双向调压塔 关阀规律 滞后关阀
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