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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:26
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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: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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天津市居民饮水类型现状及影响因素分析 被引量:1
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作者 赵亮 张可欣 +3 位作者 张磊 胡海娟 符刚 崔玉山 《环境卫生学杂志》 2025年第2期105-111,共7页
目的了解天津市居民饮水类型情况,为开展饮水人体健康风险评价提供本地化暴露途径,为饮水健康宣教和干预提供方向。方法2022年采用面对面问卷调查的方法,在天津市开展居民饮水类型和家用净水设备使用情况调查,获得饮水暴露途径。结果共... 目的了解天津市居民饮水类型情况,为开展饮水人体健康风险评价提供本地化暴露途径,为饮水健康宣教和干预提供方向。方法2022年采用面对面问卷调查的方法,在天津市开展居民饮水类型和家用净水设备使用情况调查,获得饮水暴露途径。结果共调查居民3202人,回收有效问卷3201份,问卷有效率为99.97%。60.61%的天津市居民为1种饮水类型,39.39%为多种饮水类型。管网自来水(41.02%)和家用净水器过滤水(40.83%)是主要饮水类型。不同地区、年龄、文化程度和家庭人均年收入人群饮水类型不同(P<0.05),城区偏向于饮用家用净水器过滤水(49.39%),农区偏向于饮用桶装水(43.43%);儿童青少年(43.36%)和成人(42.64%)饮用家用净水器过滤水的比例较高,老年人饮用管网自来水的比例较高(54.08%);小学及以下(49.87%)、初中(44.88%)和高中/中专/技校(47.40%)饮用管网自来水的比例较高,大专(42.38%)、本科(56.17%)和研究生及以上(55.17%)饮用家用净水器过滤水的比例较高;家庭人均年收入为<5万元(45.59%)的饮用管网自来水的比例较高,其余各家庭人均年收入(42.92%~75.44%)组别均为饮用家用净水器过滤水的比例较高。9.03%的天津市居民存在不合理使用家用净水设备的情况。结论天津市居民主要饮水类型为管网自来水和家用净水器过滤水,在进行饮用水人体健康风险评价时,应根据不同情况选取不同的饮水类型作为暴露途径。应加强对居民饮用水相关知识的科普宣传,引导居民正确使用净水设备。 展开更多
关键词 饮水类型 家用净水设备 影响因素
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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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海拉尔盆地乌北次凹小型断陷湖盆断陷期重力流沉积演化特征
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作者 南金浩 沙宗伦 +4 位作者 李跃 孔凡顺 刘少然 侯思宇 于东旭 《中国石油大学学报(自然科学版)》 北大核心 2025年第2期56-67,共12页
小型断陷湖盆具有源储距离小、储层发育等有利成藏因素,乌北次凹为典型的小型断陷湖盆,断陷期发育铜钵庙组和南屯组地层,成藏砂体以重力流沉积为主。岩心、地震、测井特征识别扇三角洲、辫状河三角洲、湖底扇等多种沉积类型基础上,以构... 小型断陷湖盆具有源储距离小、储层发育等有利成藏因素,乌北次凹为典型的小型断陷湖盆,断陷期发育铜钵庙组和南屯组地层,成藏砂体以重力流沉积为主。岩心、地震、测井特征识别扇三角洲、辫状河三角洲、湖底扇等多种沉积类型基础上,以构造-沉积学为指导重建乌北次凹断陷期重力流的构造—沉积演化。结果表明:受断陷期强构造运动影响,乌北次凹湖盆面积不断扩张,东西物源扇体交互、满盆含砂逐渐过渡为陆源扇体局限分布在湖盆周围的沉积格局;重力流沉积也由铜钵庙时期仅湖盆中心发育,逐渐过渡为南屯组大面积展布的特征;洼槽中心铜钵庙组顶部和广泛发育的南屯组的湖底扇沉积成为该区主要的油气储层;精细的沉积特征分析认为不同时期湖底扇分别为滑塌重力流和异重流2种类型,其有利目标分别为南屯组时期浊积扇体浊积水道和铜钵庙组湖底扇前端浊流砂体。 展开更多
关键词 断陷湖盆 海拉尔盆地 乌北次凹 沉积充填 滑塌型深水重力流 洪水型深水重力流
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蜡样芽胞杆菌CZBC1对硫酸盐型盐碱水体中铜绿微囊藻的溶藻效果
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作者 胡晓娟 文国樑 +5 位作者 来琦芳 杨铿 刘锦帆 苏浩昌 许云娜 曹煜成 《海洋渔业》 北大核心 2025年第5期629-637,共9页
为分析蜡样芽胞杆菌(Bacillus cereus)CZBC1在硫酸盐型盐碱水中对铜绿微囊藻(Microcystis aeruginosa)的溶藻效果,探讨了在初始铜绿微囊藻浓度为10^(5)个·mL^(-1)和10^(6)个·mL^(-1)的硫酸盐型盐碱水体中,菌株CZBC1滤液组、... 为分析蜡样芽胞杆菌(Bacillus cereus)CZBC1在硫酸盐型盐碱水中对铜绿微囊藻(Microcystis aeruginosa)的溶藻效果,探讨了在初始铜绿微囊藻浓度为10^(5)个·mL^(-1)和10^(6)个·mL^(-1)的硫酸盐型盐碱水体中,菌株CZBC1滤液组、菌体组、菌液组及对照组对铜绿微囊藻的作用效果。结果表明,菌株CZBC1对铜绿微囊藻具有直接和间接两种溶藻方式,CZBC1滤液组、菌体组和菌液组作用于微囊藻时能使微囊藻细胞变形、褪色或破裂,在硫酸盐型盐碱水体中可以发挥良好的溶藻效果。其中,当初始藻浓度为10^(5)个·mL^(-1)时,CZBC1菌液组和菌体组最高溶藻率可达99%以上;初始藻浓度为10^(6)个·mL^(-1)时,菌液组的溶藻率可达91%以上。6 d时,初始藻浓度10^(5)个·mL^(-1)组的蜡样芽孢杆菌菌量显著高于初始藻浓度10^(6)个·mL^(-1)组(P<0.05)。建议在硫酸盐型盐碱池塘中防控微囊藻水华应以预防为主,定期活化施用溶藻菌CZBC1。 展开更多
关键词 硫酸盐型盐碱水 溶藻菌 蜡样芽胞杆菌 铜绿微囊藻
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白河包营枢纽船闸上引航道口门区通航水流条件研究 被引量:1
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作者 付旭辉 张波 +2 位作者 杜洪源 何京霖 龚慧玲 《水运工程》 2025年第4期106-113,126,共9页
包营枢纽位于白河干流上游S弯道的末尾衔接段,该河段呈现出非雨期流量较小、暴雨期流量猛涨的特点,且船闸上游引航道受弯道及所处河段地形条件的影响,口门区水流条件十分紊乱,难以满足通航要求。针对船闸上游口门区复杂流态,结合坝址河... 包营枢纽位于白河干流上游S弯道的末尾衔接段,该河段呈现出非雨期流量较小、暴雨期流量猛涨的特点,且船闸上游引航道受弯道及所处河段地形条件的影响,口门区水流条件十分紊乱,难以满足通航要求。针对船闸上游口门区复杂流态,结合坝址河段特点及船闸通航要求,对枢纽上游河道整体水流条件进行数值模拟研究,通过分析不良水流条件的形成原因,提出“喇叭”式入口+透水式隔流堤的治理措施并进行比选优化。结果表明,调整岸线形状并增设合适的透水式隔流堤工程能够显著改善口门区复杂流态,确保过闸船舶的通航安全。研究结果可为类似工程提供技术参考。 展开更多
关键词 通航水流条件 “喇叭口”式护岸 口门区 弯曲河段
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湘江干流藻密度与环境因子相互关系及蓝藻水华防控策略研究
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作者 钟宇 尚可 +6 位作者 田石强 李耀宇 付广义 陈颖 郭晶 李濠 苏樑 《生态毒理学报》 北大核心 2025年第3期326-335,共10页
为研究湖库型河流藻密度与环境因子相互关系,选取湘江干流5个典型区段18个国控、省控断面,通过采样分析、数据收集等方式获取藻密度、优势门类、微囊藻毒素、水质(总磷、溶解氧、高锰酸盐指数、氨氮)、水文(流速)、气象(气温、降雨量、... 为研究湖库型河流藻密度与环境因子相互关系,选取湘江干流5个典型区段18个国控、省控断面,通过采样分析、数据收集等方式获取藻密度、优势门类、微囊藻毒素、水质(总磷、溶解氧、高锰酸盐指数、氨氮)、水文(流速)、气象(气温、降雨量、风速)等数据,分析湘江各区段水质特征及水华发生现状,研究环境因子对藻密度的影响。结果表明,湘江干流5个典型区段水质均达到地表水Ⅱ类标准,但流经衡阳段时,污染物浓度有所升高;湘江各区段优势门类均为蓝藻门,微囊藻毒素均未检出;藻密度除株洲段在6月达到最大值外,其他区段均为9月达到最大值;相关性分析表明,藻密度与水质高锰酸盐指数、总磷、气温呈显著正相关关系(P<0.05),与流速、降水量呈显著负相关关系(P<0.05);多元线性回归分析表明,水质、水文和气象条件均影响蓝藻水华发生,其中总磷、降水量、气温对藻密度的影响较大。基于环境因子对藻密度的影响,从提升监测预警能力、管控外源污染输入、加强水动力控制、提升应急处置水平等方面提出蓝藻水华防控对策。 展开更多
关键词 微囊藻毒素 湖库型河流 饮用水安全 蓝藻水华
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颜料种类与掺量对彩色透水混凝土性能影响研究 被引量:1
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作者 乔宏霞 孙鑫 +2 位作者 李琼 李奥阳 苏睿 《建筑结构》 北大核心 2025年第9期95-101,共7页
研究不同颜料种类(无机颜料、有机颜料)及掺量(0%、3%、5%、8%及10%)对彩色透水混凝土(CPC)的力学性能、透水性能及色度的影响规律。研究表明,随着无机颜料掺量的增加,力学性能呈先增后减规律,优选掺量为5%;无机颜料掺量与透水性呈负相... 研究不同颜料种类(无机颜料、有机颜料)及掺量(0%、3%、5%、8%及10%)对彩色透水混凝土(CPC)的力学性能、透水性能及色度的影响规律。研究表明,随着无机颜料掺量的增加,力学性能呈先增后减规律,优选掺量为5%;无机颜料掺量与透水性呈负相关;色度饱和度随掺量的增加呈先增后减规律,优选掺量为8%。有机颜料无论选取何掺量均会降低CPC强度,透水性能随着有机颜料掺量的增加而提高,色度饱和度随掺量的增加呈先增后减规律,优选掺量为5%,可知有机颜料对CPC的上色率影响更显著。扫描电镜SEM试验表明掺RIO可以有效改善孔结构,提高密实性。此外,X射线衍射(XRD)试验表明适量RIO可促进水泥水化作用,LRB导致Ca(OH)_(2)生成量减少。 展开更多
关键词 透水混凝土 颜料种类与掺量 力学性能 透水性能 色度性能 微观结构
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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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川中地区侏罗系沙溪庙组二段富钙地层水成因及其对天然气运聚的指示意义
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作者 杨跃明 王茂云 +6 位作者 吴长江 曾溅辉 潘珂 张欢乐 王小娟 陈冬霞 崔虎旺 《石油与天然气地质》 北大核心 2025年第1期178-191,共14页
基于34口井的地层水地球化学数据、含气饱和度数据和岩矿资料,分析了川中地区侏罗系沙溪庙组二段(沙二段)富钙地层水成因,探讨了地层水对源-储分离型致密砂岩气运聚的指示意义。研究结果表明:川中地区沙二段地层水较中国其他致密砂岩气... 基于34口井的地层水地球化学数据、含气饱和度数据和岩矿资料,分析了川中地区侏罗系沙溪庙组二段(沙二段)富钙地层水成因,探讨了地层水对源-储分离型致密砂岩气运聚的指示意义。研究结果表明:川中地区沙二段地层水较中国其他致密砂岩气藏具有明显的“钙富集和钠亏损”的特征。地层水矿化度为3.3~45.6 g/L,为CaCl_(2)型,Ca^(2+)当量比[γ(Ca^(2+))]为24.7%~69.5%。根据γ(Ca^(2+))将研究区沙二段地层水划分为高钙地层水[γ(Ca^(2+))≥60%]、中钙地层水[40%≤γ(Ca^(2+))<60%]和低钙地层水[γ(Ca^(2+))<40%]3种类型。3类地层水的化学特征和分布存在明显的差异:高钙地层水主要分布在距角①断裂相对较近且与角①断裂连通的河道砂组,矿化度平均值为34.1 g/L,相对较高,阳离子以Ca^(2+)为主,钠氯系数、脱硫酸系数和碳酸盐平衡系数最小;低钙地层水主要分布在距角①断裂较远或不与角①断裂直接连通的河道砂组,矿化度平均值为3.9 g/L,阳离子以Na^(+)为主,钠氯系数、脱硫酸系数和碳酸盐平衡系数最大;中钙地层水矿化度平均值为17.7 g/L,Na^(+)与Ca^(2+)含量相差不大,钠氯系数、脱硫酸系数和碳酸盐平衡系数介于前两者之间。Ca^(2+)含量较高的须家河组地层水的混入是沙二段地层水富钙的主要原因,后续的水-岩相互作用,尤其是斜长石的钠长石化导致钙进一步富集,而钠减少。川中地区沙二段地层水碳酸盐平衡系数、矿化度以及γ(Ca^(2+))沿着天然气侧向运移路径逐渐减少,表明富钙地层水化学指标对源-储分离型致密砂岩气藏具有较好的示踪能力。沙二段地层水中的钙越富集,储层的含气性越好,说明富钙地层水对天然气的富集具有指示意义。 展开更多
关键词 水-岩相互作用 源-储分离型气藏 富钙地层水 天然气运聚 沙溪庙组 川中地区
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炼油循环水系统冷却塔的节能改造及应用研究
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作者 翟琦 唐曼 《工业用水与废水》 2025年第4期80-84,共5页
通过对炼油循环水系统冷却塔的淋水填料、配水系统、收水器进行节能改造,冷却塔E6205处理水量提升500 m^(3)/h,冷却能力由原来的87.4%提升至97.4%,能效提升至GB/T 7190.2—2018《机械通风冷却塔第2部分:大型开式冷却塔》中的4级能效标准... 通过对炼油循环水系统冷却塔的淋水填料、配水系统、收水器进行节能改造,冷却塔E6205处理水量提升500 m^(3)/h,冷却能力由原来的87.4%提升至97.4%,能效提升至GB/T 7190.2—2018《机械通风冷却塔第2部分:大型开式冷却塔》中的4级能效标准,冷却水飘水率降低至0.001%以下,节水量约为720 m^(3)/a,节电量约为40.87×10^(4) kW·h/a,折合降低碳排放约为237.46 t/a。改造后实现了增冷效、降能耗、减碳排的目的。 展开更多
关键词 循环水系统 冷却塔 横流式 逆流式 淋水填料 配水系统 收水器 节能改造
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2021~2023年山西省河流水环境质量特征分析 被引量:1
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作者 王爱花 史明 +3 位作者 刘金涛 惠晓梅 毋晓琴 李超 《水电能源科学》 北大核心 2025年第4期89-93,共5页
掌握近年山西省河流水环境质量变化规律,对后续更有针对性地开展河流污染治理与保护具有重要意义。基于2021~2023年山西省地表水国控、省控逐月水质数据,分析全省及主要流域不同水质类型比例和主要污染指标现状,采用Mann-Kendall(M-K)... 掌握近年山西省河流水环境质量变化规律,对后续更有针对性地开展河流污染治理与保护具有重要意义。基于2021~2023年山西省地表水国控、省控逐月水质数据,分析全省及主要流域不同水质类型比例和主要污染指标现状,采用Mann-Kendall(M-K)趋势检验和系统聚类法探究水质变化规律。结果表明,2021~2023年全省河流水环境呈改善趋势,优良水体(Ⅰ~Ⅲ类)断面比例显著上升,污染水体(Ⅳ~劣V类)断面比例显著下降;当前全省污染源以农业、生活污染为主,但依然存在工业污染风险,其中,化学需氧量、生化需氧量、高锰酸盐指数、总磷在4~10月易成为污染指标,而氨氮在每年的11月~次年3月易成为污染指标;六大流域河流水质均有不同程度地好转,但涑水河、汾河、桑干河、滹沱河污染水体断面比例依然较高;全省及主要流域3年逐月水质状况主要分为3类,水质较差的一类集中在2021年大部分月份及2022、2023年春夏季个别月份,水质好的一类主要包括2022、2023年大部分月份,春夏季为未来水环境治理需要重点关注的时期。 展开更多
关键词 水质类型变化 污染指标 M-K趋势检验 系统聚类法 山西省
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煤矿井下定向孔绕障探放老空水技术研究与应用
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作者 方有向 王力 +5 位作者 张磊 黄寒静 景慎怀 豆旭谦 张敬才 陈洪岩 《煤炭技术》 2025年第4期159-164,共6页
常规钻孔探放水存在探放距离短、钻孔轨迹偏差大、探查结果不可靠、无法长距离定向精准探放等问题,亟需成套定向钻孔探放水技术,特别是已有巷道、工作面等绕障长距离定向探放老空水技术。针对煤矿老空水空间分布特征,分析了井下探放老... 常规钻孔探放水存在探放距离短、钻孔轨迹偏差大、探查结果不可靠、无法长距离定向精准探放等问题,亟需成套定向钻孔探放水技术,特别是已有巷道、工作面等绕障长距离定向探放老空水技术。针对煤矿老空水空间分布特征,分析了井下探放老空水定向钻孔施工关键技术,研究了煤矿井下定向钻进绕障防碰方法,提出了探放老空水定向钻进配套装备,在淮南丁集矿、顾桥矿进行了定向钻孔绕障探放老空水工程应用,采用“U”型绕障定向钻孔轨迹设计,分别从运顺、底板巷钻场开孔钻进施工长距离定向钻孔4个,钻孔深度360.5~609 m,全部绕过已有巷道精确钻进至采空区,钻孔放水量保持在21 m^(3)/h以上,最大放水量达123 m^(3)/h。现场应用结果表明,定向钻孔是精准探放老空水的有效手段,探放距离远、施工安全性好;采用“U”型定向钻孔绕障可靠性高、轨迹控制难度小、放水效果好,为类似条件采用定向钻孔绕障进行老孔区探放水提供了新技术。 展开更多
关键词 老空水探放 “U”型定向钻孔 绕障 煤矿井下
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