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双特色背景下应用型高校水利类专业改造升级探索与实践--以水利水电工程专业为例
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作者 刘江川 王岩 康思宇 《长春工程学院学报(社会科学版)》 2024年第2期123-126,共4页
为适应产业发展和社会需求,为区域经济产业的可持续健康发展提供水利类方面的人才支撑,基于专业的优势与特色,考虑吉林省特色高水平专业的要求,以长春工程学院水利水电工程专业改造升级为例,从培养方案顶层设计、课程体系优化设置、教... 为适应产业发展和社会需求,为区域经济产业的可持续健康发展提供水利类方面的人才支撑,基于专业的优势与特色,考虑吉林省特色高水平专业的要求,以长春工程学院水利水电工程专业改造升级为例,从培养方案顶层设计、课程体系优化设置、教学资源拓展建设、学习效果过程评价、实习实践能力提升等方面,探索应用型水利水电工程传统专业改造升级的途径,以期对进一步丰富和完善应用型水利类专业的建设提供一定借鉴。 展开更多
关键词 双特色 应用型本科 水利水电工程专业 改造升级
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Three-dimensional hydrodynamic model of Xiamen waters 被引量:5
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作者 WenShenghui CaiSong +1 位作者 TangJunjian CaiQifu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期151-170,共20页
A semi-implicit and Eulerian - Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-moment turbulence closure model and tr... A semi-implicit and Eulerian - Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-moment turbulence closure model and transport equations of salinity and temperature. The simulation for flooding and drying of mudflats has been improved. The model is applied to Xiamen waters. Based on extensive survey data, water level elevation, temperature and salinity field along the eastern open boundary and at the Jiulong River inlets and runoffs are analyzed, specified and calibrated. The computed results show good agreement with the measured data, reproduce flooding, emergence of large and complex mudflat region. 展开更多
关键词 Semi-implicit finite difference scheme Eulerian - Lagrangian approach three-dimensional shallow water flow Xiamen waters
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The diffusive fluxes of inorganic nitrogen across the intertidal sediment-water interface of the Changjiang Estuary in China 被引量:5
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作者 HOU Lijun LIU Min +3 位作者 XU Shiyuan LU Jianjian OU Dongni YU Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第3期48-57,共10页
Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitu... Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitudes of the benthic exchange fluxes were determined on the basis of concentration gradients of ammonium and nitrate at the near-bottom water and interstitial water interface in combination with calculations of a modified Fick' s first law. Ammonium fluxes varied from - 5.05 to 1.43 μg/( cm^2·d) and were greatly regulated by the production of ammonium in surface sediments, while nitrate fluxes ranged from - 0. 38 to 1.36 μg/ ( cm^2·d) and were dominated by nitrate concentrations in the tidal water. It was found that ammonium was mainly released from sediments into water columns at most of stations whereas nitrate was mostly diffused from overlying waters to intertidal sediments. In total, 823.75 t/a ammonium-N was passed from intertidal sediments to water while about 521.90 t/a nitrate-N was removed from overlying waters to intertidal sediments. This suggests that intertidal sediments had the significant influence on modulating inorganic nitrogen in the tidal water. 展开更多
关键词 AMMONIUM NITRATE sediment - water interface intertidal flat Changjiang Estuary
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Using irrigation intervals to optimize water-use efficiency and maize yield in Xinjiang,northwest China 被引量:7
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作者 Guoqiang Zhang Dongping Shen +10 位作者 Bo Ming Ruizhi Xie Xiuliang Jin Chaowei Liu Peng Hou Jun Xue Jianglu Chen Wanxu Zhang Wanmao Liu Keru Wang Shaokun Li 《The Crop Journal》 SCIE CAS CSCD 2019年第3期322-334,共13页
Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yiel... Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation. 展开更多
关键词 Irrigation frequency Soil moisture MAIZE High yield(>15 Mg ha^(-1)) water use efficiency
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Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage 被引量:2
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作者 Chuan-Zhi Cui Jian-Peng Xu +3 位作者 Duan-Ping Wang Zhi-Hong Liu Ying-song Huang Zheng-Ling Geng 《Petroleum Science》 SCIE CAS CSCD 2016年第2期272-279,共8页
Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to impro... Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %. 展开更多
关键词 water-flooded reservoirs Layer regrouping.Flow resistance - High water cut Reservoir simulation
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The Coupling Coordination Evolution Research of Economy - Ecology - Society System in Xinjiang:Based on the Interaction Perspective of Water Resources 被引量:1
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作者 Chen Junke Li Hong +1 位作者 Wang Xibo Ma Yongren 《Meteorological and Environmental Research》 CAS 2017年第5期73-77,共5页
Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-econo... Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-economy-ecology-society system,quantitative evaluation and analysis of the coupling coordination of the water resources-economy-ecology-society system from 2001 to 2014 were conducted. The results showed that benefit indexes of economic system and social system grew rapidly,while benefit indexes of water resources system and ecosystem fluctuated smoothly from 2001 to 2014; coupling state of the whole system was at rival stage,and coupling coordination was reluctant coordination type,and the coupling index was slightly higher than the coupling coordination index. Moreover,it showed that the more the coupling systems,the lower indices of coupling and the coupling coordination. 展开更多
关键词 water resources - ECONOMY - ECOLOGY - SOCIETY SYSTEM COUPLING coordination Evolution XINJIANG
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Effects of Different NH_4^+/NO_3^- Ratio and Water Condition on Physiological Characteristics of Rice Seedlings
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作者 Haimei WU Xiaoyuan CHEN +1 位作者 Yupeng ZHANG Fujie WU 《Agricultural Science & Technology》 CAS 2017年第10期1908-1911,1924,共5页
[Objective] This study aimed to further explore the dynamics of related physiological indexes of rice seedlings under different NH4+ /NO3- ratio and different water condition. [Method] Under the hydroponic condition ... [Objective] This study aimed to further explore the dynamics of related physiological indexes of rice seedlings under different NH4+ /NO3- ratio and different water condition. [Method] Under the hydroponic condition in laboratory, 3 NH4+/NO3- ratios (0/100, 50/50 and 100/0) and 2 water conditions (+PEG,-PEG) were designed for Fengliangyou 7203. [Result] The root-canopy ratio of rice seedlings increased under any of the NH4+/NO3- ratios and water conditions. Under water stress, the root-canopy ratio of rice seedlings changed most greatly at the NH4+/NO3- ratio of 0/ 100; the overall water potential of rice seedlings reached the lowest at the NH4+/ NO3- ratio of 100/0; and the changes of water potential and xylem flow pH were relatively stable at the NH4+/NO3- ratio of 50/50. Under the condition of no water stress, the growth of rice seedlings was best at the NH4+/NO3- ratio of 50/50, followed by the NH4+/NO3- ratios of 0/100 and 100/0. [Conclusion] This study will pro- vide a basis for understanding the relationship between water potential and xylem flow. 展开更多
关键词 Rice NH4+/NO3- ratio water stress water potential Root-canopy ratio
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Lithium Behavior in Salt-water System Explored by Molecular Dynamics Simulation
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作者 MA Yanfang LIU Jianchuan +1 位作者 LI Kanshe ZHANG Zhihong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第6期1016-1020,共5页
The molecular dynamics simulation method was adopted to study the transient characteristics of Li^+,CO3^2-,and SO4^2- in Na^+,K^+,Li^+,Cl^-,and SO4^2-/H2O system.The composition of Na^+,K^+,Li^+,Cl^-,SO4^2- and CO3^2-... The molecular dynamics simulation method was adopted to study the transient characteristics of Li^+,CO3^2-,and SO4^2- in Na^+,K^+,Li^+,Cl^-,and SO4^2-/H2O system.The composition of Na^+,K^+,Li^+,Cl^-,SO4^2- and CO3^2- was selected to optimize the initial structural model and conduct dynamic simulation.The mean azimuth shift and diffusion coefficient of Li^+,CO3^2-,and SO4^2- in the system,the radial distribution function and potential energy between Li^+ and -OW,SO4^2- and -OW as well as CO3^2- and -OW,and the dielectric constant of hydrogen bond were expounded and analyzed.At the same time,the Li enrichment behavior in the evaporation process of salt lake brine was analyzed based on the simulated data.The results show that the simulation results are in good agreement with the experimental values,which verifies that,compared with other ions,the crystallization of Li^+ and SO4^2- occurs earlier after reaching saturation. 展开更多
关键词 salt lakes Li^+ CO3^2- SO4^2- MD salt water system
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Determination of 16 Species of OCPs in Water by Liquid-liquid Extraction-GC
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作者 Li Ting Zhu Weiping +1 位作者 Xu Xiuyan Yang Hui 《Meteorological and Environmental Research》 CAS 2014年第1期55-58,共4页
[Objective] The research aimed to study the determination of 16 kinds of OCPs in water by liquid-liquid extraction -GC. [Method] The new method for determining 16 kinds of OCPs in water by liquid-liquid extraction -GC... [Objective] The research aimed to study the determination of 16 kinds of OCPs in water by liquid-liquid extraction -GC. [Method] The new method for determining 16 kinds of OCPs in water by liquid-liquid extraction -GC was established, and the influencing factors such as nitrogen pressure and water bath temperature were discussed. [ Result] Detection limit of the method was from 3.2 to 14.1 ng/L, the relative standard deviation was between 4.0% and 9.6%, and the average recovery ranged from 80.8% to 106.0%. By optimizing nitrogen pressure and water bath temperature in the sample pretreatment process, when nitrogen pressure was +0.087 kPa, and water bath temperature was ±36 ℃, recovery effect of this method was better. [ Conclusion] The determination method had accurate qualitative and quantitative results, and met detection requirement of 16 kinds of OCPs in water. 展开更多
关键词 Liquid-liquid extraction - GC OCPS Nitrogen pressure water bath temperature China
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Preliminary Study on Water Demand Law of 1-0 Rooted Cuttings of Populus szechuanica
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作者 Dabuqiong Haoyu WANG +2 位作者 Huanhuan XIE Zhen XING Yanhui YE 《Meteorological and Environmental Research》 CAS 2021年第4期39-42,共4页
In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and ... In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and the law of water demand of P.szechuanica was grasped.In this paper,potted seedlings of 1-0 rooted cuttings of P.szechuanica were taken as research objects,and change situation of water consumption under different water control gradients was measured regularly by using weighing method,further analyzing dynamic change of water consumption of P.szechuanica and revealing water demand law of 1-0 rooted cuttings of P.szechuanica.The results showed that total change of water consumption of 1-0 rooted cuttings of P.szechuanica had"slow-fast-slow-fast"double-peak trend in the growth period of the current year,and corresponded with univariate linear relation(R^(2)=0.7137),with significant difference.In whole growth period,water consumption in August was the highest,which was 2.7 times of that in June and July and 1.5 times of that after September.In different water control treatments,the dynamic changes of daily and monthly water consumption were significantly different.In seven water control treatments,monthly water consumption was between(6315.95±1690.70)and(10105.28±3065.30)g/month,and mean was(8211.07±2308.23)g/month.With intensification of water control treatment,water consumption increased,but there was no seedling death due to water shortage.P.szechuanica has great plasticity in water demand,and can survive in both arid and humid environments.Meanwhile,it is revealed that P.szechuanica is the most widely distributed tree species in the region. 展开更多
关键词 Populus szechuanica 1-0 rooted cuttings water consumption water demand law
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2015 IWA Alternative Water Resources Conference Nanjing,China(May 26-28,2015)
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《Water Science and Engineering》 EI CAS CSCD 2015年第2期174-174,共1页
The IWA Alternative Water Resources(AWR)Conference is organized by the International Water Association,Hohai University,the IWA China Chapter of the AWR Cluster,and the Seawater Desalination and AWR Utilization Rese... The IWA Alternative Water Resources(AWR)Conference is organized by the International Water Association,Hohai University,the IWA China Chapter of the AWR Cluster,and the Seawater Desalination and AWR Utilization Research Center of Hohai University. 展开更多
关键词 IWA Alternative water Resources Conference Nanjing China May 26-28 2015
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Water-Deficit Response Is Not Affected by Glutathione Deficiency in Arabidopsis thaliana pad2-1 Plants
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作者 Tana Jubany-Marí Seán Meehan +1 位作者 Marta López-Carbonell Leonor Alegre 《American Journal of Plant Sciences》 2016年第14期2020-2037,共18页
Changes in glutathione and ascorbate content, hydrogen peroxide and abscisic acid were studied in developing leaves in wild-type (Col-0) and glutathione-deficient mutant pad2-1 lines of Arabidopsis thaliana over a tim... Changes in glutathione and ascorbate content, hydrogen peroxide and abscisic acid were studied in developing leaves in wild-type (Col-0) and glutathione-deficient mutant pad2-1 lines of Arabidopsis thaliana over a time period of 9 days of drought followed by re-watering. Glutathione deficient mutant (pad2-1) presents mechanisms of acclimation to water stress through the reduction of plant biomass and increase in endogenous concentrations of ascorbate and glutathione. These acclimation responses to stress appeared along with the first symptoms of stress and we suggest here that they are regulated by ABA and H<sub>2</sub>O<sub>2</sub>. Normally, wild type plants under conditions of stress require an initial response phase in which a decrease in antioxidants is observed before reaching acclimation through the increase in levels of antioxidants. pad2-1 is more sensitive to stress and reacts to it;however, it did not suffer more oxidative stress than Col-0 plants, even though pad2-1 had higher levels of endogenous H<sub>2</sub>O<sub>2</sub> relative to wild-type. In both water stressed Col-0 and pad2-1 plants increases in ABA were observed, however, more sharply in wild-type stressed plants. Low levels of glutathione together with high levels of H<sub>2</sub>O<sub>2</sub> may regulate endogenous ABA concentrations and could be related to the slow growth rates which were observed during the experiment. The results highlighted the double function of glutathione as an antioxidant and signal molecule and also, the different response patterns of wild-type and pad2-1 when faced with drought stress. The results bring new insights to the responses of pad2-1 under conditions of water stress. 展开更多
关键词 Abscisic Acid ANTIOXIDANTS Growth Hydrogen Peroxide pad2-1 water Stress
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Water and nitrogen transport characteristics of single-line interference infiltration under film hole irrigation with muddy water and fertilizer
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作者 JIANG Ruirui FEI Liangjun KANG Shouxuan 《排灌机械工程学报》 CSCD 北大核心 2022年第5期496-503,共8页
Based on the experimental data,this study investigated the effect of sand content of muddy water on water and nitrogen transport characteristics of the single-line interference infiltration under film hole irrigation ... Based on the experimental data,this study investigated the effect of sand content of muddy water on water and nitrogen transport characteristics of the single-line interference infiltration under film hole irrigation with muddy water and fertilizer.The relationship between the single-line interference infiltration parameters,the sand content,the wetting front movement distances,and the sand content were all established.The model of the cumulative infiltration volume of per unit film pore area,the vertical and horizontal wetting front movement distance of the free surface,and the wetting front movement distance of the interference center with sand content and infiltration time were proposed.Reveal the law of the change of soil water content and the distribution of NO_(3)^(-)-N content based on different muddy water sand content.The results indicate that at the same infiltration time,as the muddy water sand content increases,the cumulative infiltration volume per unit pore area decreases.The infiltration index of the free infiltration and the single-line interference vary little when the sand content increases,mainly are around 0.64 and 0.58.The relationship between infiltration parameters a,b and the sand content is linear function.At the same location,the more the sand content,the smaller the wetting front movement distance in free surface and the single-line interference surface,the less the NO_(3)^(-)-N content. 展开更多
关键词 film hole irrigation single-line interference infiltration muddy water FERTILIZER sand content NO_(3)^(-)-N content
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Isobaric Vapor–Liquid Equilibrium for tert-Butyl Alcohol + Water + Propane-1,3-Diol + 1-Ethyl-3-Methylimidazolium Chloride at 101.3 kPa
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作者 Xianbao Cui Qinglong Cheng +5 位作者 Haofei Liu Lexing Xue Jinbo Zhou Ying Zhang Tianyang Feng Kai Zhang 《Transactions of Tianjin University》 EI CAS 2018年第5期424-433,共10页
In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobari... In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobaric vapor–liquid equilibrium(VLE) for the quaternary system TBA + water + propane-1,3-diol + [emim]Cl at 101.3 kPa, and found the VLE data to be well correlated with the nonrandom two-liquid model. These results show that the mixed solvent of propane-1,3-diol + [emim]Cl can increase the relative volatility of TBA to water and break the azeotropic point. We found no notable synergetic effect between them, and observed that the liquid mixed solvent of propane-1,3-diol and [emim]Cl had lower viscosity than [emim]Cl, which makes it a promising entrainer for separating the TBA + water azeotrope in industrial applications. 展开更多
关键词 tert-Butyl alcohol·water·Propane-1-3-diol·1-Ethyl-3-methylimidazolium chloride·Vapor–liquid EQUILIBRIUM
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Advice on IELTS Speaking Teaching Based on Applied Linguistics Theory
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作者 陈宁 《科技视界》 2018年第21期135-136,共2页
As more and more Chinese students are trying to study abroad, IELTS becomes one of the most important tests all around China. After years’development, IELTS speaking teaching still meets certain difficulties. This pa... As more and more Chinese students are trying to study abroad, IELTS becomes one of the most important tests all around China. After years’development, IELTS speaking teaching still meets certain difficulties. This paper gives specific advice based on certain applied linguistics theory, i. e. Grammar-translation Method, Audiolingualism, and Natural Order Hypothesis, trying to provide enlightenment for future IELTS speaking teaching. 展开更多
关键词 applied LINGUISTICS IELTS SPEAKING TEACHING GRAMMAR - translation Method Audio - lingualism Natural Order Hypothesis
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GC-MS法测定水源水中的半挥发性有机物 被引量:22
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作者 刘晓茹 高继军 +1 位作者 刘玲花 袁浩 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期183-186,共4页
  我国于2002年6月1日实施了地表水环境质量标准(GB3838-2002),其中集中式生活饮用水地表水源地特定项目中规定了68种有机污染物的监测,包括挥发性有机物(VOCs)和半挥发性有机物(SVOCs),其中半挥发性有机物的类别较多,有硝基苯、氯苯...   我国于2002年6月1日实施了地表水环境质量标准(GB3838-2002),其中集中式生活饮用水地表水源地特定项目中规定了68种有机污染物的监测,包括挥发性有机物(VOCs)和半挥发性有机物(SVOCs),其中半挥发性有机物的类别较多,有硝基苯、氯苯、苯胺、苯酚、有机氯农药、有机磷农药、多环芳烃和多氯联苯等有机污染物,分析方法以气相色谱为主.…… 展开更多
关键词 GC - MS Semivolatile organic compounds Source water
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超重力-臭氧法处理TNT红水的试验研究 被引量:25
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作者 刘有智 刁金祥 +3 位作者 王贺 李鹏 康荣灿 焦纬洲 《火炸药学报》 EI CAS CSCD 2006年第6期41-44,共4页
为提高O3氧化处理TNT红水的功效和利用率,节约水处理成本,将具有高效传质特性的旋转填料床用于研究O3氧化处理TNT红水的特性规律。考察了超重力因子β、红水初始pH值和气液比等因素对红水COD去除率的影响。结果表明,β对COD去除率有明... 为提高O3氧化处理TNT红水的功效和利用率,节约水处理成本,将具有高效传质特性的旋转填料床用于研究O3氧化处理TNT红水的特性规律。考察了超重力因子β、红水初始pH值和气液比等因素对红水COD去除率的影响。结果表明,β对COD去除率有明显的影响,随着pH值的增大β对COD去除率的影响增大,β大于100后对COD去除率的影响不明显;COD去除率随气液比的增加呈先减小后增大的趋势;COD去除率随pH值的增大而升高,当pH值超过11时,COD去除率有所下降。通过试验证明了该方法在技术上是可行的,具有良好的应用前景。 展开更多
关键词 应用化学 废水处理 超重力 旋转填料床 臭氧 TNT红水
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柴达木地区滴灌水-盐-肥综合调控对枸杞生长和水肥利用的影响 被引量:12
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作者 万书勤 康跃虎 +2 位作者 刘士平 孙甲霞 卢健 《节水灌溉》 北大核心 2016年第5期37-41,47,共6页
针对柴达木盆地枸杞生产对水-肥-盐综合管理的需求,布置了5个滴灌施肥灌溉比例(施肥量分别为当地枸杞施肥量的10%、30%、50%,70%、90%)的田间试验,试验通过控制滴头正下方20cm处的土壤基质势下限为-20kPa进行滴灌水盐调控和施肥灌溉。... 针对柴达木盆地枸杞生产对水-肥-盐综合管理的需求,布置了5个滴灌施肥灌溉比例(施肥量分别为当地枸杞施肥量的10%、30%、50%,70%、90%)的田间试验,试验通过控制滴头正下方20cm处的土壤基质势下限为-20kPa进行滴灌水盐调控和施肥灌溉。结果表明:在柴达木地区,当滴头正下方20cm深度土壤基质势控制在-20kPa以上时,滴灌施肥灌溉阶段土壤盐分会增加,但是土壤仍属于非盐渍土,低耐盐植物可以生长;冬灌盐分淋洗效果显著,冬灌后土壤盐分基本可以维持平衡;随着施肥比例的增加,枸杞的株高、茎粗、冠幅增长率及干鲜果产量先增加再降低,当施肥比例为70%时达到最大;滴灌高频施肥灌溉有利于提高枸杞的产量、灌溉水利用效率和肥料利用率,并且当施肥比例为当地枸杞施肥量的70%左右时,枸杞产量高、灌溉水利用效率高、肥料偏生产力高。 展开更多
关键词 滴灌施肥 水盐调控 土壤基质势 灌溉水利用效率 肥料偏生产力
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主路式水肥一体机施肥系统的设计与试验
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作者 李擎 李家春 +1 位作者 熊贤沙 蔡家斌 《农机化研究》 北大核心 2025年第2期68-74,共7页
针对现阶段水肥一体化设备存在施肥不均、自动化程度不高及滞后性严重的问题,根据现代化农业节水省肥和减少环境污染的灌溉要求,设计了一款可实现自动混肥、施肥、节水灌溉的主路式水肥一体化施肥机。根据液肥的EC和pH值调节过程的特点... 针对现阶段水肥一体化设备存在施肥不均、自动化程度不高及滞后性严重的问题,根据现代化农业节水省肥和减少环境污染的灌溉要求,设计了一款可实现自动混肥、施肥、节水灌溉的主路式水肥一体化施肥机。根据液肥的EC和pH值调节过程的特点,开发了以SIEMENS S7-1200为核心的液肥控制系统硬件,并结合MatLab设计了以模糊PID为控制器的液肥EC和pH值控制系统。为验证施肥机在实际应用中的精确性和鲁棒性,设计了施肥系统动态调节性能试验,结果表明:在施肥阶段,模糊PID控制系统具有较短的稳态时间和较小的超调量,相比于PID控制系统,对EC和pH值进行调节的稳态时间分别减少了37.7%和52.1%,稳态超调量分别降低了1.2%和2.2%,可实现对混肥溶液进行迅速有效的调节,满足现代农业实际生产需要。 展开更多
关键词 水肥一体化 施肥机 模糊PID 过程控制
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Waters HPLC检测蔬菜、水果中7种农药残留方法优化 被引量:8
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作者 任超 聂晶 +2 位作者 莎娜 连海飞 温都苏 《内蒙古农业科技》 2012年第2期52-53,共2页
参考现有方法,依据实验室条件,使用Waters2695 HPLC配2998 PDA检测器,检测蔬菜水果中吡虫啉、啶虫脒、多菌灵、除虫脲、灭幼脲、辛硫磷、阿维菌素7种农药残留。通过优化得到良好的分离效果,控制在30min内完成。外标定量分析时,标准曲线R... 参考现有方法,依据实验室条件,使用Waters2695 HPLC配2998 PDA检测器,检测蔬菜水果中吡虫啉、啶虫脒、多菌灵、除虫脲、灭幼脲、辛硫磷、阿维菌素7种农药残留。通过优化得到良好的分离效果,控制在30min内完成。外标定量分析时,标准曲线R2值在0.9996~0.9999,回收率在87.9%~105.1%,灵敏度和精密度满足分析要求。 展开更多
关键词 waters2695-2998 农药残留 优化
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