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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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Effects of Meat and Phosphate Level on Water-Holding Capacity and Texture of Emulsion-Type Sausage During Storage 被引量:24
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作者 WANG Peng,XU Xing-lian and ZHOU Guang-hong Key Laboratory of Meat Processing and Quality Control,Ministry of Education/Nanjing Agricultural University,Nanjing 210095,P.R.China 《Agricultural Sciences in China》 CSCD 2009年第12期1475-1481,共7页
This paper was designed to verify the influence of phosphate on water-holding capacity (WHC) and texture of emulsiontype sausage prepared with pre-rigor meat, ageing meat or frozen meat. Pre-rigor pork, ageing pork ... This paper was designed to verify the influence of phosphate on water-holding capacity (WHC) and texture of emulsiontype sausage prepared with pre-rigor meat, ageing meat or frozen meat. Pre-rigor pork, ageing pork and frozen pork were pre-blended with five levels of phosphate and made into emulsion-type sausage. The yield, hardness and total expressible fluid (TEF) were measured with texture profile analysis machine and pressiometer when emulsion-type sausage was produced. Meanwhile, hardness and purge loss (PL) were measured during 30 d storage. As emusion-type sausage made by pre-rigor meat, higher yield and relatively stable hardness could be found. It indicated that increasing of phosphate level caused an alleviatable effects in increasing of hardness when emulsion-type sausage made by pre-rigor meat, but opposite effects made by ageing meat or frozen meat. The distribution of PL of emulsion-type sausage was found to be affected by phosphate addition. Significant decrease of PL could not be obtained by increasing of phosphate level during storage. Pre-rigor meat improved WHC and texture of emulsion-type sausage. Problem of WHC and texture of emulsiontype sausage during storage could not be resolved by single use of phosphate at relatively higher level (3%) of NaCl. 展开更多
关键词 MEAT emulsion-type sausage water-holding capacity TEXTURE
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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:13
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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:5
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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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滇中地区主要森林凋落物有效截留量及其影响因素 被引量:2
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作者 王平 李璐杉 +1 位作者 丁智强 李玉辉 《水土保持研究》 CSCD 北大核心 2024年第3期213-221,229,共10页
[目的]研究滇中地区主要森林类型凋落物有效截留量差异及其影响因素,为该地未来植被恢复和森林管理提供科学支撑。[方法]利用样方调查法、烘干法和浸泡法分析了昆明市双河—磨南德水源林自然保护区内的地带性次生常绿阔叶林(SF)、针阔... [目的]研究滇中地区主要森林类型凋落物有效截留量差异及其影响因素,为该地未来植被恢复和森林管理提供科学支撑。[方法]利用样方调查法、烘干法和浸泡法分析了昆明市双河—磨南德水源林自然保护区内的地带性次生常绿阔叶林(SF)、针阔混交林(TF)、旱冬瓜林(ACF)、华山松林(PA)、成熟云南松林(OPY)、幼龄云南松林(YPY)、银荆林(AD)7种主要森林类型凋落物未分解层(OL)和半分解层(OF)的有效截留量及其影响因素。[结果](1) 7种森林类型凋落物厚度为2.06~7.57 cm,其中OL层1.10~4.30 cm, OF层0.83~3.93 cm,凋落物层厚度排序为TF>ACF>PA>OPY>SF>AD>YPY,凋落物蓄积量为4.75~17.45 t/hm^(2),其中OL层占比为32.02%~62.48%,OF层占比为37.52%~67.98%,凋落物层蓄积量排序为TF>PA>SF>OPY>ACF>AD>YPY。(2)凋落物最大持水率为115.3%~170.7%,初始吸水速率为3.65~5.62 g/(g·h),凋落物持水率和浸水时间的关系可用对数函数y=aln(x)+b表示,吸水速率与浸水时间可用幂函数y=kt~n表示。(3)凋落物最大持水量为7.05~32.19 t/hm^(2),排序为PA>TF>SF>OPY>ACF>AD>YPY,有效截留量为5.45~25.34 t/hm^(2),以TF最高(25.34t/hm^(2)),PA(24.99 t/hm^(2))和SF(24.62 t/hm^(2))次之,YPY最低(5.45t/hm^(2)),影响有效截留量的场地特征主要为蓄积量、自然含水率、分解强度以及厚度,影响有效截留量的水动力过程主要是最大失水量、前6.0 h平均吸水速率和前2.0 h平均吸水速率。[结论]滇中地区未来植树造林应以针阔混交林为主,注重对地带性次生常绿阔叶林的保育,采取辅助自然更新的措施促进人工纯林向混交林演化,同时减少踩踏、收集凋落物等人类活动的干扰,从而增加森林生态系统凋落物的水源涵养能力。 展开更多
关键词 凋落物 主要森林类型 持水特性 有效截留量 滇中地区
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白云南洼珠海组陆架坡折带演化特征与深水沉积耦合关系
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作者 张尚锋 范东旭 +4 位作者 李宏义 唐武 王雅宁 朱锐 李冉 《海洋地质前沿》 CSCD 北大核心 2024年第7期11-24,共14页
白云南洼珠海组沉积时期,盆地处于断陷向拗陷转化阶段,陆架坡折形态以及位置发生巨大变化,导致深水沉积的类型和特征具有明显差异。针对这种坡折演化对深水沉积类型的影响开展研究,通过对白云南洼珠海组三维地震剖面进行解译,识别珠海... 白云南洼珠海组沉积时期,盆地处于断陷向拗陷转化阶段,陆架坡折形态以及位置发生巨大变化,导致深水沉积的类型和特征具有明显差异。针对这种坡折演化对深水沉积类型的影响开展研究,通过对白云南洼珠海组三维地震剖面进行解译,识别珠海组各层段陆架坡折带,定量分析坡折特征及其演化规律,探讨坡折演化过程与深水沉积的耦合关系。研究结果表明,通过对珠海组沉积时期陆架坡折带定量分析,将其迁移演化类型划分为下降型、平直型、低角度上升型、高角度上升型4类;在井震结合的基础上,根据地震相组合以及沉积体系分布特点,识别出斜坡扇、块状搬运沉积、深水水道体、盆底扇4种主要的深水沉积类型;并发现陆架坡折演化类型与深水沉积类型存在明显的耦合关系:平直型、高角度上升型、低角度上升型和下降型陆架边缘迁移轨迹分别对应斜坡扇、块状搬运沉积、深水水道体和盆底扇的优势发育。此外,珠海组四段至珠海组三段陆架坡折带整体由下降型向低角度上升型转变,深水沉积体系以斜坡扇及深水水道体发育为主;珠海组三段至珠海组一段早期整体由低角度上升型向下降型转变,深水沉积体系以深水水道-盆底扇沉积体系为主;珠海组一段晚期整体由下降型向高角度上升型演化,深水沉积体系几乎不发育。本研究揭示了陆架坡折迁移对深水沉积体系类型和分布的控制作用,对深入理解深水沉积过程和油气勘探具有重要意义。 展开更多
关键词 坡折带 深水沉积类型 沉积演化 珠海组 白云南洼 珠江口盆地
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水滴形大跨钢屋盖结构风洞试验和风振分析
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作者 郑江 王凯 王先铁 《建筑结构》 北大核心 2024年第18期103-111,共9页
自然风经过大跨结构时,由于结构屋顶形状不规则,通常会引起柔性屋面的振动,因此针对大跨屋面结构抗风设计需要考虑风压分布和风振响应。以陕西省水务集团矿泉水生产车间为工程背景,制作了1∶200的刚性模型,通过刚性模型风洞试验测得该... 自然风经过大跨结构时,由于结构屋顶形状不规则,通常会引起柔性屋面的振动,因此针对大跨屋面结构抗风设计需要考虑风压分布和风振响应。以陕西省水务集团矿泉水生产车间为工程背景,制作了1∶200的刚性模型,通过刚性模型风洞试验测得该水滴型大跨钢屋盖结构的表面风压,研究了屋盖表面典型测点及整体的风压分布规律。基于风洞试验数据,对结构进行风振时程分析,得到了屋盖表面的风振响应和风振系数。结合刚性模型风洞试验和风振分析,深入研究了水滴形大跨屋盖结构的风压分布规律和风致振动特性,并总结了其共性规律。 展开更多
关键词 水滴形大跨钢屋盖结构 刚性模型 风洞试验 时程分析 风压分布 风振系数
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宁南黄土区不同人工植被类型深层土壤水分亏缺评价
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作者 王月玲 许浩 +4 位作者 安钰 万海霞 董立国 韩新生 袁心 《甘肃农业大学学报》 CAS CSCD 北大核心 2024年第2期215-223,共9页
【目的】开展评估不同人工植被类型深层土壤水分亏缺程度,能为区域科学合理实施植被恢复策略提供理论依据。【方法】以宁夏彭阳中庄小流域5种不同植被类型(山桃林、沙棘林、柠条林、苜蓿地,农田为对照)为研究对象,采用土壤水分相对亏缺... 【目的】开展评估不同人工植被类型深层土壤水分亏缺程度,能为区域科学合理实施植被恢复策略提供理论依据。【方法】以宁夏彭阳中庄小流域5种不同植被类型(山桃林、沙棘林、柠条林、苜蓿地,农田为对照)为研究对象,采用土壤水分相对亏缺指数(CSWDI)和干燥化指数(SDI)定量评价模型,对不同植被类型下0~1 000 cm土壤水分亏缺及干燥化程度进行定量化分析与评价。【结果】不同植被类型深层土壤水分变化特征差异明显,0~1 000 cm平均土壤水分含量呈现出农地(16.29%)>山桃林(13.06%)>沙棘林(12.22%)>柠条林(9.12%)>苜蓿地(8.08%)。在垂直剖面上,土壤水分随土层深度增加总体呈现先减小后增加再逐渐稳定的趋势。在0~1 000 cm农地基本没有水分亏缺和干层发生,山桃林、柠条林、沙棘林和苜蓿地均呈现不同程度的土壤水分亏缺现象,平均土壤水分相对亏缺指数分别为0、0.22、0.62、0.35、0.79,平均土壤干燥化指数分别为185.5%、67.45%、51.55%、87.35%、36.10%,5种植被类型中苜蓿地土壤水分亏缺最严重,其次为柠条林、沙棘林、山桃林、农地。山桃林、柠条林、沙棘林、苜蓿地均有不同程度的干层分布,分别呈现中度、轻度和严重干燥化,干层厚度(DSLT)分别为890、860、800、920 cm,DSL-SWC分别为12.42%、8.14%、11.56%、7.76%。【结论】宁南黄土区不同人工植被类型对深层土壤水分亏缺具有明显影响,导致不同程度土壤干层发生,其中苜蓿地土壤水分亏缺最严重,应采取相应措施恢复土壤水分,促进区域水土资源可持续利用和生态健康发展。 展开更多
关键词 植被类型 土壤水分 水分亏缺 宁南黄土区
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氨型碱性水化学对690TT腐蚀特性的影响
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作者 赵永福 唐敏 +5 位作者 姜峨 银朝晖 陈子瑞 张根 吴宗佩 李杨 《材料导报》 EI CAS CSCD 北大核心 2024年第7期167-172,共6页
为探索氨型碱性水化学对传热管材料690TT腐蚀行为的影响,开展传热管材料690TT合金在B-Li-NH_4OH和NH_4OH两种水质下的腐蚀特性研究,分析690TT腐蚀产物释放特性,综合评价氨型碱性水质对690TT腐蚀特性的影响。研究结果表明,690TT材料与两... 为探索氨型碱性水化学对传热管材料690TT腐蚀行为的影响,开展传热管材料690TT合金在B-Li-NH_4OH和NH_4OH两种水质下的腐蚀特性研究,分析690TT腐蚀产物释放特性,综合评价氨型碱性水质对690TT腐蚀特性的影响。研究结果表明,690TT材料与两种氨型碱性水质均具有较好的相容性。690TT在两种水质中均形成了致密的氧化膜,氧化膜由NiFe_(2)O_(4)尖晶石氧化物和少量的铁氧化物Fe_(2)O_(3)组成,相对而言690TT在NH_(4)OH型水质条件下的总腐蚀失重量、总腐蚀产物释放量略低于在B-Li-NH_(4)OH水质下,但690TT向水质释放的Ni元素总量与上述规律相反,这可能与Ni元素和氨形成络合物[Ni(NH_(3))_(m)]^(2+)有关,Ni元素释放量增加对反应堆一回路辐照场控制有不利影响。本研究结果可为氨型碱性水化学技术的设计和应用提供数据支撑。 展开更多
关键词 氨型碱性水化学 镍基合金690TT 腐蚀
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地下水型饮用水水源补给区划分——以辽宁省沈阳市北部某地区饮用水水源为例 被引量:1
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作者 王英刚 唐小涵 +3 位作者 岳景鹏 金赵明 王子兴 赵杨帆 《沈阳大学学报(自然科学版)》 CAS 2024年第3期198-204,共7页
选择辽宁省沈阳市北部某地区集中式地下水型饮用水水源作为研究区,收集其地形地貌、水源所属地下水含水系统的地质和水文地质概况等相关信息进行分析。选择公式法,根据含水层岩性,采取经验值参数,以水源开采井保护区外为基准,以15 a(547... 选择辽宁省沈阳市北部某地区集中式地下水型饮用水水源作为研究区,收集其地形地貌、水源所属地下水含水系统的地质和水文地质概况等相关信息进行分析。选择公式法,根据含水层岩性,采取经验值参数,以水源开采井保护区外为基准,以15 a(5475 d)为地下水质点迁移时间,计算得出补给区面积为40.18 km^(2)。鉴于补给区边界部分横跨村庄,在补给区定界过程中,将横跨村庄纳入补给区范围内,切实加强补给区安全防护。并从补给区环境管理方面提出对策和建议。 展开更多
关键词 地下水型饮用水水源 公式法 补给区划分 地下水流向 水文地质
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雷火灸治疗阳虚水泛型慢性心力衰竭临床研究
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作者 路超 贾海莲 张克清 《新中医》 CAS 2024年第14期107-113,共7页
目的:观察雷火灸治疗阳虚水泛型慢性心力衰竭的临床疗效。方法:选取102例阳虚水泛型慢性心力衰竭患者,按随机数字表法分为常规治疗组和雷火灸治疗组各51例,2组各剔除1例,最终各纳入50例。常规治疗组给予西药治疗,雷火灸治疗组在常规治... 目的:观察雷火灸治疗阳虚水泛型慢性心力衰竭的临床疗效。方法:选取102例阳虚水泛型慢性心力衰竭患者,按随机数字表法分为常规治疗组和雷火灸治疗组各51例,2组各剔除1例,最终各纳入50例。常规治疗组给予西药治疗,雷火灸治疗组在常规治疗组基础上给予雷火灸治疗。比较2组临床疗效、中医证候评分、6 min步行试验(6MWT)距离、明尼苏达心衰生活质量量表(MLHFQ)评分及心、肾功能指标水平,记录不良反应。结果:治疗后,雷火灸治疗组临床疗效优于常规治疗组(P<0.05)。2组中医证候、MLHFQ评分均较治疗前降低(P<0.05),雷火灸治疗组中医证候、MLHFQ评分均低于常规治疗组(P<0.05)。2组6MWT距离均较治疗前增大(P<0.05),雷火灸治疗组6MWT距离大于常规治疗组(P<0.05)。2组可溶性基质裂解素2 (sST2)、磷脂酰肌醇3激酶(PI3K)、嗜铬粒蛋白A (CgA)、游离脂肪酸(FFA)、血肌酐(SCr)水平及心肌能量消耗(MEE)、左室收缩末圆周室壁应力(cESS)值均较治疗前降低(P<0.05),雷火灸治疗组sST2、PI3K、CgA、FFA、SCr水平及MEE、左室cESS值均低于常规治疗组(P<0.05)。2组左室射血分数(LVEF),右室收缩期峰值应变率(SRs)、舒张早期峰值应变率(SRc)、舒张晚期峰值应变率(SRa),以及肾小球滤过率(GFR)均较治疗前升高(P<0.05),雷火灸治疗组LVEF,右室SRs、SRc、SRa,以及GFR均高于常规治疗组(P<0.05)。2组左室心肌质量指数(LVMI)、左室收缩末期内径(LVESd)均较治疗前缩小(P<0.05),雷火灸治疗组LVMI、LVESd均小于常规治疗组(P<0.05)。治疗期间2组均无不良反应发生。结论:雷火灸治疗阳虚水泛型慢性心力衰竭,可调节sST2、PI3K、CgA、FFA等指标水平,改善临床症状及心肾结局,减缓心室重构,提升活动耐力及生活质量。 展开更多
关键词 慢性心力衰竭 阳虚水泛型 雷火灸 心室重构 肾功能 活动耐力 生活质量
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溶藻菌CZBC1在氯化物型盐碱水中对铜绿微囊藻的溶藻效果研究
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作者 胡晓娟 杨铿 +6 位作者 文国樑 苏浩昌 许云娜 徐创文 徐煜 徐武杰 曹煜成 《南方水产科学》 CAS CSCD 北大核心 2024年第5期169-175,共7页
为研发氯化物型盐碱水体溶藻菌菌剂,选取溶藻菌菌株CZBC1,探讨了滤液组、菌体组、菌液组在初始铜绿微囊藻(Microcystis aeruginosa)密度分别为10^(5)和10^(6)个·mL^(-1)的氯化物型盐碱水中对铜绿微囊藻的溶藻效果。结果发现,菌株CZ... 为研发氯化物型盐碱水体溶藻菌菌剂,选取溶藻菌菌株CZBC1,探讨了滤液组、菌体组、菌液组在初始铜绿微囊藻(Microcystis aeruginosa)密度分别为10^(5)和10^(6)个·mL^(-1)的氯化物型盐碱水中对铜绿微囊藻的溶藻效果。结果发现,菌株CZBC1同时具有直接和间接2种溶藻方式,菌株CZBC1的滤液组、菌体组、菌液组作用于铜绿微囊藻时能使藻细胞变形、褪色或破裂,在氯化物型盐碱水体中可以发挥良好的溶藻效果。当初始藻密度为10^(5)个·mL^(-1)时,第6天菌液组的铜绿微囊藻密度可降至2.30×10个·mL^(-1),菌体组降至1.27×10~2个·mL^(-1),对照组为3.67×10^(5)个·mL^(-1),菌液组和菌体组极显著低于对照组(p<0.01),2组的最高溶藻率可达99%以上。当初始藻密度为10^(6)个·mL^(-1)时,第6天菌液组的铜绿微囊藻密度可降至8.30×10^(5)个·mL^(-1),对照组为3.17×10^(6)个·mL^(-1),菌液组显著低于对照组(p<0.05),最高溶藻率为78.8%。从溶藻效果来看,菌液组>菌体组>滤液组。研究表明,溶藻菌CZBC1在氯化物型盐碱水中对铜绿微囊藻具有良好的溶藻效果,可用于氯化物型盐碱池塘中的微囊藻水华防控。 展开更多
关键词 溶藻菌 铜绿微囊藻 蜡样芽胞杆菌 氯化物型盐碱水
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以实践目标为导向的本科生课程教学改革
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作者 宋亚丽 郑磊 +2 位作者 朱文芳 潘翠霞 陈勇民 《科技风》 2024年第16期18-20,共3页
针对新形势下的工科专业培养要求,提出了以实践目标为导向的给排水科学与工程专业“水的特种处理”课程教学改革方案。在对本课程进行现状分析并提出课程存在不足的基础上,开展了以培养学生的工程实践应用和科技创新能力为目标的课程实... 针对新形势下的工科专业培养要求,提出了以实践目标为导向的给排水科学与工程专业“水的特种处理”课程教学改革方案。在对本课程进行现状分析并提出课程存在不足的基础上,开展了以培养学生的工程实践应用和科技创新能力为目标的课程实践,将课程进行模块化分类并注重课程的成果输出,强化课程团队建设与过程评价体系,以期为工科专业的课程改革和人才培养提供一定的借鉴。 展开更多
关键词 实践目标 水的特种处理 教学改革 给排水科学与工程
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动水压力型巨厚滑坡削坡方案优化效果评价
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作者 金国辉 赵新 《价值工程》 2024年第29期14-16,共3页
动水压力型巨厚滑坡削坡工程方案应用广泛,然而当前多依赖于实际经验辅以计算,理论发展滞后于工程实践,在实际工程建设中迫切需求合理有效评价方案设计的优劣。本文以动水压力型巨厚滑坡削坡方案为抓手,通过实地调查、寻访专家,分析滑... 动水压力型巨厚滑坡削坡工程方案应用广泛,然而当前多依赖于实际经验辅以计算,理论发展滞后于工程实践,在实际工程建设中迫切需求合理有效评价方案设计的优劣。本文以动水压力型巨厚滑坡削坡方案为抓手,通过实地调查、寻访专家,分析滑坡削坡方案设计特点,运用层次分析法选取了评价指标,构建了方案优化效果分析与评价的指标体系,运用模糊综合评价法构建优化效果综合评估模型并在实际工程中应用验证。 展开更多
关键词 动水压力型 巨厚滑坡 削坡
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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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降雨-蒸发作用下土石坝渗流场及坝坡稳定性研究
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作者 吴凡 王从锋 王云峰 《三峡大学学报(自然科学版)》 北大核心 2024年第1期30-35,共6页
为探究降雨-蒸发作用对非饱和土坝坡渗流场与稳定性的影响,运用Geo-studio软件分析华南某水库坝坡在不同降雨类型和边界条件下的孔隙水压力和安全系数的变化规律.结果表明:相同降雨等级下,递增型降雨的孔隙水压力上升速率随降雨的持续... 为探究降雨-蒸发作用对非饱和土坝坡渗流场与稳定性的影响,运用Geo-studio软件分析华南某水库坝坡在不同降雨类型和边界条件下的孔隙水压力和安全系数的变化规律.结果表明:相同降雨等级下,递增型降雨的孔隙水压力上升速率随降雨的持续而增大,递减型降雨减小,集中型降雨先增大后减小,稳定性安全系数的下降速率与孔隙水压力上升速率相对应;相同降雨时间下,孔隙水压力与稳定性安全系数的变化幅度从大到小为:递减型>集中型>递增型;降雨与蒸发作用条件下,递减型降雨的安全系数的下降率最大,对于坝坡稳定性为最不利影响;土地气候相互作用边界条件下各降雨类型的孔隙水压力增长速率和安全系数降低速率均要小于单位流量边界条件,但安全系数均要大于单位流量边界条件,降雨-蒸发作用下所反映的渗流场与稳定性变化更符合实际. 展开更多
关键词 降雨-蒸发作用 降雨类型 边界条件 孔隙水压力 安全系数
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