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Contacted Ion Pairs in Aqueous CuCl2 by the Combination of Ratio Spectra, Difference Spectra, Second Order Difference Spectra in the UV-Visible Spectra
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作者 鞠思文 张宁 +4 位作者 王志强 张睿挺 曾德文 邵晓鹏 林珂 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第6期657-663,I0001,I0002,共9页
The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the... The microstructure of aqueous CuCl2 has been studied through lots of technologies for many years; however, it remains a controversial subject. In this study, a new spectroscopic method has been proposed to analyze the UV-visible spectra of thin fihn of CuCl2/H2O solutions at different concentrations. This method is the combination of ratio spectra, difference spectra and second order difference spectra. By using this method, two new bands at -230 and -380 nm are obviously observed. The bands are assigned as the contacted ion pairs [CuCl3(H2O)n]- or [CuCl4(H2O)n]2-, which demonstrates that ion pairs exist in the CuCl2/H2O solution. Such finding agrees with the recent theoretical spectra obtained by time-dependent density functional theory. Furthermore, the populations of the contacted ion pairs are discussed. This study not only offers the direct spectroscopic evidence of [CuCl3(H2O)n]- or [CuCl4(H2O)n]2- in aqueous CuCl2, but also suggests that the spec- troscopic analysis method is powerful to extract the weak bands in a strong overlapping spectrum. 展开更多
关键词 UV-visible spectroscopy ratio spectra Difference spectra CuCl2/H2O solution ion pair
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Direct Determination of Potassium-Sodium Activity Ratio in Soil Suspension with Two Ion-Selective Electrodes 被引量:1
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作者 LIHONG-YAN JIGUO-LIANG 《Pedosphere》 SCIE CAS CSCD 1991年第4期363-369,共7页
A K+-selective electrode and a Na+-selective electrode were used to construct a measuring cell without liquid-junction for the determination of the ion activity ratio of K+ to Na+ in soil suspensions. The measured cel... A K+-selective electrode and a Na+-selective electrode were used to construct a measuring cell without liquid-junction for the determination of the ion activity ratio of K+ to Na+ in soil suspensions. The measured cell potential was not affected by the total electrolyte concentration when the total cation concentration was 10-1-10-3 mol L-1 and the concentration ratio CK+ / CNa+. was 10:1 to 1:50. When the concentration ratios were equal to 1and the total electrolyte concentrations were 10-2 and 10-3 mol L-1, the ion activity ratio measurement would not be affected by pH in the pH range of 3.5 to 11.5 and 4.4 to 11 respectively. Ions other than H+ have no remarkable influence on the measurement. The ion activity ratio of K+ to Na+ measured directly in soil suspension agree well with those in centrifuged supernant solution. The relative deviation was within 4%. From the measured ion activity ratio, the difference of the bonding energies of K+ and Na+ ions was calculated. 展开更多
关键词 ion activity ratio ion-selective electrode potassium ion sodium ion
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Experimental Study on Chloride Ion Penetration Resistance of Coal Gangue Concrete under Multi-Factor Comprehensive Action 被引量:1
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作者 Hongyu Chen Hongguang Zhu +1 位作者 Hongqiang Ma Mingyue Zhang 《World Journal of Engineering and Technology》 2019年第2期58-64,共7页
In order to investigate the chloride ion penetration resistance of coal gangue concrete under multi-factor comprehensive action, the non-steady-state accelerated chloride ion migration test was used to test the chlori... In order to investigate the chloride ion penetration resistance of coal gangue concrete under multi-factor comprehensive action, the non-steady-state accelerated chloride ion migration test was used to test the chloride diffusion law of coal gangue concrete specimens by crack width, curing temperature and water-cement ratio. Three groups of crack width (0 mm, 0.05 - 0.12 mm, 0.12 - 0.2 mm), three curing temperatures (high temperature 45, medium temperature 25, low temperature 10), three water cement ratios (0.3, 0.4, 0.5) were set in the experiment. The results show that when the curing temperature and water cement ratio are constant, the crack width less than 0.12 mm has little effect on the chloride content and chloride diffusion coefficient. When the crack width is larger than 0.12 mm, the chloride penetration depth increases with the crack width. The resistance to chloride ion penetration of gangue concrete is greatly influenced by the water cement ratio. The influ-ence degree of three factors on chloride ion migration coefficient of gangue concrete is as follows: water cement ratio > crack width > curing temperature. 展开更多
关键词 Coal GANGUE Concrete CHLORIDE ion PENETratioN Water CEMENT ratio Crack WIDTH CURING Temperature
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Influence and determinative factors of ion-to-atom arrival ratio in unbalanced magnetron sputtering systems 被引量:8
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作者 Jun Zhou Zhe Wu Zhanhe Liu 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期775-781,共7页
Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputterin... Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputtering, by producing dense secondary plasma around the substrate, provides a high ion current density. The closed-field unbalanced magnetron sputtering system (CFUBMS) has been established as a versatile technique for high-rate deposition high-quality metal, alloy, and ceramic thin films. The'key factor in the CFUBMS system is the ability to transport high ion currents to the substrate, which can enhance the formation of full dense coatings at relatively low value homologous temperature. The investigation shows that the energy of ions incidenced at the substrate and the ratio of the flux of these ions to the flux of condensing atoms are the fundamental parameters in determining the structure and properties of films produced by ion-assisted deposition processes. Increasing ion bombardment during deposition combined with increasing mobility of the condensing atoms favors the formation of a dense microstructure and a smooth surface. 展开更多
关键词 magnetron sputtering closed-field unbalanced magnetron sputtering system (CFUBMS) ion-to-atom ratio unbalancedmagnetron sputtering
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Contribution of patchy reconnection to the ion-to-electron temperature ratio in the Earth’s magnetotail 被引量:3
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作者 ChuXin Chen Chih-Ping Wang 《Earth and Planetary Physics》 CSCD 2019年第6期474-480,共7页
The ion-to-electron temperature ratio is a good indicator of the processes involved in the plasma sheet.Observations have suggested that patchy reconnection and the resulting earthward bursty bulk flows(BBFs)transport... The ion-to-electron temperature ratio is a good indicator of the processes involved in the plasma sheet.Observations have suggested that patchy reconnection and the resulting earthward bursty bulk flows(BBFs)transport may be involved in causing the lower temperature ratios at smaller radial distances during southward IMF periods.In this paper,we estimate theoretically how a patchy magnetic reconnection electric field can accelerate ions and electrons differently.If both ions and electrons are non-adiabatically accelerated only once within each reconnection,the temperature ratio would be preserved.However,when reconnection occurs closer to the Earth where magnetic field lines are shorter,particles mirrored back from the ionosphere can cross the reconnection region more than once within one reconnection;and electrons,moving faster than ions,can have more crossings than do ions,leading to electrons being accelerated more than ions.Thus as particles are transported from tail to the near-Earth by BBFs through multiple reconnection,electrons should be accelerated by the reconnection electric field more times than are ions,which can explain the lower temperature ratios observed closer to the Earth. 展开更多
关键词 the ion-to-electron temperature ratio plasma sheet patchy magnetic RECONNECTion non-adiabatical acceleration
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Control of Beam Energy and Flux Ratio in an Ion-Beam-Background Plasma System Produced in a Double Plasma Device
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作者 WEI Zian MAJinxiu +2 位作者 LI Yuanrui SUN Yan JIANG Zhengqi 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第11期1076-1080,共5页
Plasmas containing ion beams have various applications both in plasma technology and in fundamental research. The ion beam energy and flux are the two factors characterizing the beam properties. Previous studies have ... Plasmas containing ion beams have various applications both in plasma technology and in fundamental research. The ion beam energy and flux are the two factors characterizing the beam properties. Previous studies have not achieved the independent adjustment of these two parameters. In this paper, an ion-beam-background-plasma system was produced with hotcathode discharge in a double plasma device separated by two adjacent grids, with which the beam energy and flux ratio (the ratio between the beam flux and total ion flux) can be controlled independently. It is shown that the discharge voltage (i.e., voltage across the hot-cathode and anode) and the voltage drop between the two separation grids can be used to effectively control the beam energy while the flux ratio is not affected by these voltages. The flux ratio depends sensitively on hot-filaments heating current whose influence on the beam energy is relatively weak, and thus enabling approximate control of the flux ratio 展开更多
关键词 ion beam background plasma beam energy flux ratio
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Saturation Ion Current Densities in Inductively Coupled Hydrogen Plasma Produced by Large-Power Radio Frequency Generator
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作者 WANG Songbai LEI Guangjiu +3 位作者 BI Zhenhua H. GHOMI YANG Size LIU Dongping 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第9期907-911,共5页
An experimental investigation of the saturation ion current densities (Jions) in hydrogen inductively coupled plasma (ICP) produced by a large-power (2-32 kW) radio frequency (RF) generator is reported, then s... An experimental investigation of the saturation ion current densities (Jions) in hydrogen inductively coupled plasma (ICP) produced by a large-power (2-32 kW) radio frequency (RF) generator is reported, then some reasonable explanations are given out. With the increase of RF power, the experimental results show three stages: in the first stage (2-14 kW), the electron temperature will rise with the increase of RF power in the ICP, thus, the Jions increases continually as the electron temperature rises in the ICP. In the second stage (14 20 kW), as some H- ions lead to the mutual neutralization (MN), the slope of Jio^s variation firstly decreases then increases. In the third stage (20-32 kW), both the electronic detachment (ED) and the associative detachment (AD) in the ICP result in the destruction of H- ions, therefore, the increased amplitude of the Jions in the third stage is weaker than the one in the first stage. In addition, with the equivalent transformer model, we successfully Explain that the Jions at different radial locations in ICP has the same rule. Finally, it is found that the Jions has nothing to do with the outer/inner puffing gas pressure ratio, which is attributed to the high-speed movement of hydrogen molecules. 展开更多
关键词 saturation ion current densities large-power RF generator outer/innerpuffing gas pressure ratio H- ion transformer model
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Inter-stage line ratio of He- and Li-like Ti emissions for the electron temperature measurement
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作者 李向东 王成 +1 位作者 韩申生 徐至展 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第2期2764-2766,共3页
Under coronal conditions, the steady state rate-equations are used to calculate the inter-stage line ratios between Li-like ls22p(2P3/2)→ls22s(2S1/2) and He-like ls2p(1P1)→1s2(1S0) transitions for Ti in the electron... Under coronal conditions, the steady state rate-equations are used to calculate the inter-stage line ratios between Li-like ls22p(2P3/2)→ls22s(2S1/2) and He-like ls2p(1P1)→1s2(1S0) transitions for Ti in the electronic temperature ranges from 0.1keV to 20 keV. The results show that the temperature sensitivities are higher at the electronic temperature less than 5000 eV and the temperature sensitivities will decrease with the increase of electronic temperature. 展开更多
关键词 inter-stage line ratio electron temperature measurement Li-like ion
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Experimental study of cross-section ratios in the collisions of C^(q+) and O^(q+) (q=1-4) on atomic helium in strong-interaction region 被引量:1
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作者 陈熙萌 江丽娟 +12 位作者 周鹏 周春林 高志民 邱玺玉 崔莹 王兴安 娄凤君 吕学阳 贾娟娟 陈林 邵剑雄 吕瑛 王幡 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期322-327,共6页
We have measured the cross-section ratios of helium induced by Cq+ and Oq+ (q = 1-4) in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method ... We have measured the cross-section ratios of helium induced by Cq+ and Oq+ (q = 1-4) in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method combined with the MPA-3 data acquisition system. Hence, we obtain the ratios of total single-ionization cross-sections (SI, SC, SLSI, and DLSI), total double-ionization cross-sections (DI, DC, TI, SLDI, and DLDI) and cross-sections of every process (SI, SC, SLSI, DLSI, DI, DC, TI, SLDI, and DLDI), which induce the single-ionization and double-ionization, to the total cross sections respectively. The competitive relations between the reaction-channels and the experimental data law of each reaction-channel are revealed explicitly, and the qualitative explanations involved in those results are also presented accordingly. 展开更多
关键词 ion-atom collisions strong-interaction region cross-section ratios competitive relation
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Seasonal shifts in the solute ion ratios of vadose zone rock moisture from the Eel River Critical Zone Observatory
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作者 Jennifer L.Druhan Nicole Fernandez +2 位作者 Jia Wang William E.Dietrich Daniella Rempe 《Acta Geochimica》 EI CAS CSCD 2017年第3期385-388,共4页
One of the greatest challenges in critical zone studies is to document the moisture dynamics, water flux,and solute chemistry of the unsaturated, fractured and weathered bedrock that lies between the soil and groundwa... One of the greatest challenges in critical zone studies is to document the moisture dynamics, water flux,and solute chemistry of the unsaturated, fractured and weathered bedrock that lies between the soil and groundwater table. The central impediment to quantifying this component of the subsurface is the difficulty associated with direct observations. Here, we report solute chemistry as a function of depth collected over a full year across the shale-derived vadose zone of the Eel River Critical Zone Observatory using a set of novel sub-horizontal wellbores,referred to as the vadose zone monitoring system. The results of this first geochemical glimpse into the deep vadose zone indicate a dynamic temporal and depth-resolved structure. Major cation concentrations reflect seasonal changes in precipitation and water saturation, and normalized ratios span the full range of values reported for the world's largest rivers. 展开更多
关键词 Vadose zone Solute ion ratios Critical Zone OBSERVATORY Seasonal solute dynamics
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Effects of Groundwater with Various Salinities on Evaporation and Redistribution of Water and Salt in Saline-sodic Soils in Songnen Plain,Northeast China
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作者 ZHU Wendong ZHAO Dandan +6 位作者 YANG Fan WANG Zhichun DONG Shide AN Fenghua MA Hongyuan ZHANG Lu TIBOR Tóth 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1141-1152,共12页
Groundwater mineralization is one of the main factors affecting the transport of soil water and salt in saline-sodic areas.To investigate the effects of groundwater with different levels of salinity on evaporation and... Groundwater mineralization is one of the main factors affecting the transport of soil water and salt in saline-sodic areas.To investigate the effects of groundwater with different levels of salinity on evaporation and distributions of soil water and salt in Songnen Plain,Northeast China,five levels of groundwater sodium adsorption ration of water(SARw)and total salt content(TSC mmol/L)were conducted in an oil column lysimeters.The five treated groundwater labeled as ST0:0,ST0:10,ST5:40,ST10:70 and ST20:100,were prepared with NaCl and CaCl2 in proportion,respectively.The results showed the groundwater evaporation(GWE)and soil evaporation(SE)increased firstly and then decreased with the increase of groundwater salinity.The values of GWE and SE in ST10:70 treatment were the highest,which were 2.09 and 1.84 times the values in the ST0:0 treatment with the lowest GWE and SE.There was a positive linear correlation between GWE and the Ca^(2+)content in groundwater,with R^(2)=0.998.The soil water content(SWC)of ST0:0 treatment was significantly(P<0.05)less than those of other treatments during the test.The SWC of the ST0:0 and ST0:10 treatments increased with the increase of soil depth,while the other treatments showed the opposite trend.Statistical analysis indicated the SWC in the 0–60 cm soil layer was positively correlated with the groundwater TSC and its ion contents during the test.Salt accumulation occurred in the topsoil and the salt accumulation in the 0–20 cm soil layer was significantly(P<0.05)greater than that in the subsoil.This study revealed the effects of the salinity level of groundwater,especially the Ca^(2+)content and TSC of groundwater,on the GWE and distributions of soil water and salt,which provided important support for the prevention and reclamation of soil salinization and sodificaton in shallow groundwater regions. 展开更多
关键词 groundwater evaporation sodium adsorption ratio total salt content ion composition soil salinization water and salt dynamics Songnen Plain China
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4-6 Measurement of the Ratio of C3+ and O4+ Ions Produced by ECR Source to Prepare a Laser Cooling Experiment at Storage Rings
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作者 Zhu Xiaolong Wen Weiqiang +16 位作者 Ma Xinwen Li Jinyu Feng Wentian Zhang Ruitian Yan Shuncheng Guo Dalong Hai Bang Qian Dongbin Zhang Pengju Xu Shenyue Zhao Dongmei Yang Jie Zhang Dacheng Li Bin Gao Yong Huang Zhongkui Wang Hanbing 《IMP & HIRFL Annual Report》 2014年第1期184-184,共1页
The cooling of heavy ions can provide high-quality beams that are especially important for high-precisionexperimental nuclear and atomic physics. The laser cooling of relativistic C3+ ion beams at the experimental coo... The cooling of heavy ions can provide high-quality beams that are especially important for high-precisionexperimental nuclear and atomic physics. The laser cooling of relativistic C3+ ion beams at the experimental coolerstorage ring (CSRe) is being currently prepared at Institute of Modern Physics (IMP) in Lanzhou. An electroncyclotron resonance ion source (ECRIS) will be used to produce C3+ ion beams. Meanwhile, O4+ ions could alsobe produced due to residual gas because of the same mass-to-charge ratio. Therefore, both C3+ and O4+ ion beamswill be injected and circulate in a storage ring during the laser cooling experiment at the same time. A higher ratioof C3+ ions will lead to a better result for the laser cooling experiment. 展开更多
关键词 Measurement ratio ionS
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南北疆典型绿洲水化学特征差异与时空变化规律分析——以策勒和阜康为例
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作者 马玉 刘小龙 +2 位作者 张鹏伟 摆翔 彭磊 《安徽农业科学》 2025年第1期63-69,101,共8页
利用水化学指标、离子含量特征、Piper图、Gibbs图、主要离子比例关系和USSL图法,以中国西北干旱区新疆南(策勒)北(阜康)2个绿洲为例,对2005—2019年天然水体的水化学特征进行分析。结果表明:2005—2019年阜康地下水离子浓度与溶解性固... 利用水化学指标、离子含量特征、Piper图、Gibbs图、主要离子比例关系和USSL图法,以中国西北干旱区新疆南(策勒)北(阜康)2个绿洲为例,对2005—2019年天然水体的水化学特征进行分析。结果表明:2005—2019年阜康地下水离子浓度与溶解性固体总量(TDS)波动较大,总体呈下降趋势,地表水离子含量变化并不明显;2个绿洲区的TDS与其他各离子含量之间均存在较好的相关性,天然水体的矿化度主要由Na^(+)与SO_(4)^(2-)控制。策勒水化学类型为Na^(+)-Cl^(-)型和混合型,阜康水化学类型为Ca^(2+)-HCO_(3)^(-)、Na_(+)-Cl^(-)型和混合型;阜康的流动地表水主要受碳酸盐岩风化的影响,静止地表水受硅酸盐岩的风化作用的影响,硅酸盐岩和蒸发盐岩的风化是地下水组分的主要控制因素;策勒的地表水和地下水化学组分均受硅酸盐岩与碳酸盐岩风化的影响。 展开更多
关键词 水化学 时空变化规律 Piper图 水-岩相互作用 离子比 干旱区绿洲
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苏北滨海县深层地下水化学特征及成因
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作者 汪名鹏 《地质论评》 北大核心 2025年第1期245-256,共12页
江苏滨海县地下水资源丰富,深层地下水一直是当地居民生活、生产的重要供水水源之一。为了查明苏北滨海县深层地下水化学特征及其控制因素,保障地下水资源开发和供水安全,采集研究区内深层地下水(第Ⅱ、Ⅲ、Ⅳ承压水)和海水样品共43件... 江苏滨海县地下水资源丰富,深层地下水一直是当地居民生活、生产的重要供水水源之一。为了查明苏北滨海县深层地下水化学特征及其控制因素,保障地下水资源开发和供水安全,采集研究区内深层地下水(第Ⅱ、Ⅲ、Ⅳ承压水)和海水样品共43件。结合研究区水文地质条件、地下水开采现状,综合采用数理统计分析、Piper三线图、Gibbs图、Schoeller图、离子相关性分析和离子比值分析等方法,分析深层含水层不同类型地下水化学组成及水化学类型空间分布特征,探讨深层地下水水化学组分的控制作用和成因机制。结果表明:①滨海县域范围内深层地下水总体上呈中—弱碱性,不同类型地下水平面上存在差异,总体上由西向东(由陆向海)呈增大趋势。②水化学类型具有明显的水平分带性。第Ⅱ承压水以Cl^(-)·HCO_(3)^(-)—Na^(+)型和HCO_(3)^(-)—Na^(+)型为主;第Ⅲ承压水以Cl^(-)·HCO_(3)^(-)—Na^(+)型和HCO_(3)^(-)·Cl^(-)—Na^(+)型为主;第Ⅳ承压水均为Cl^(-)·HCO_(3)^(-)—Na^(+)型水。随深度增加,地下水水化学类型由多元向单一转变。③研究区水化学特征受水—岩作用、阳离子交换作用的影响。岩石风化溶解是水化学特征的主要控制因素,且阳离子交换作用活跃,深层地下水中Ca^(2+)、Mg^(2+)、HCO_(3)^(-)等主要来源于硅酸盐矿物的溶解,Na^(+)、SO_(4)^(2-)、Cl^(-)等主要来源于蒸发盐岩、硫酸盐矿物的溶解。目前深层地下水水化学特征尚未明显受到地下水长期过量开采等人类活动的影响,为避免或减缓地下水水位下降引起的深层地下水水质咸化等环境问题,建议合理布局深层地下水开采井,并合理调控取量。研究结果对江苏滨海地区深层地下水资源可持续开发利用和环境保护具有重要的意义。 展开更多
关键词 深层地下水 水化学特征 水化学成因 离子比值 滨海县
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一种用于MCP的新型防离子反馈膜
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作者 张妮 孙超 +7 位作者 杨凯莉 朱宇峰 焦岗成 邱洪金 李朋博 郝子恒 黄武军 王江浩 《红外技术》 北大核心 2025年第1期115-120,共6页
传统技术制备的MCP防离子反馈膜在一定程度上会影响像管的信噪比,长时间的工作条件下也会降低像管的可靠性,基于传统防离子反馈膜缺陷导致的像管信噪比和可靠性性能亟需改善和提高的迫切需求,开展一种用于MCP的新型防离子反馈膜研究。... 传统技术制备的MCP防离子反馈膜在一定程度上会影响像管的信噪比,长时间的工作条件下也会降低像管的可靠性,基于传统防离子反馈膜缺陷导致的像管信噪比和可靠性性能亟需改善和提高的迫切需求,开展一种用于MCP的新型防离子反馈膜研究。采用原子层沉积技术(Atomic Layer Deposition,ALD)在有较高长径比的MCP通道内壁及输入端的通道孔处制备一层连续的高质量U型结构的防离子反馈膜,经MCP综合检测装置测试,与传统技术制备的MCP部件性能相比,新型防离子反馈膜致密,增益值较高,部件含碳量低,新型防离子反馈膜的MCP部件经制管后像管信噪比高,寿命可靠性高,此技术制备的新型防离子反馈MCP部件对与像增强器信噪比和可靠性性能的提升具有重要意义。 展开更多
关键词 新型防离子反馈膜 原子层沉积技术 高长径比 信噪比 长寿命
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Sorption of Heavy Metal and Organic Pollutants on Modified Soils 被引量:33
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作者 MENG Zhao-Fu ZHANG Yi-Ping WANG Guo-Dong 《Pedosphere》 SCIE CAS CSCD 2007年第2期235-245,共11页
Sorption characteristics of both an organic pollutant (phenol) and a heavy metal (cadmium ion) on the clay layer of a Lou soil (Eum-orthic Anthrosol in Chinese Soil Taxonomy) along with the sorption mechanism were inv... Sorption characteristics of both an organic pollutant (phenol) and a heavy metal (cadmium ion) on the clay layer of a Lou soil (Eum-orthic Anthrosol in Chinese Soil Taxonomy) along with the sorption mechanism were investigated using three soil treatments: modification with a cationic surfactant cetyltrimethylammonium bromide added at an amount equivalent to 50% and 100% of the soil CEC (50%CB and 100%CB), modification with an amphoteric surface-modifying agent dodecyldimethylbetaine (commercially known as BS-12) added at an amount equivalent to 50% and 100% of the soil CEC (50% BS and 100%BS), and an unmodified control (CK). Results showed that the BS soil treatments increased sorption of both the heavy metal Cd2+ and the organic pollutant phenol. The equilibrium sorption amount of Cd2+ decreased in the order: 50%BS > 100%BS > CK > 50%CB > 100%CB, with the BS soil treatments being about 1.3 to 1.8 times higher and the CB soil treatments about 23% to 41% lower than CK. Both the single-site and two-site Langmuir models could be applied to describe the sorption of Cd2+ in each soil treatment. The equilibrium sorption amount of phenol on the soil samples decreased in the order: 100%CB > 50%CB > 100%BS > 50%BS > CK, with the CB soil treatments being 41.0 to 79.6 times higher and the BS soil treatments 4.0 to 8.3 times higher than CK. The Freundlich equation could also be used to describe the sorption characteristics of phenol. In the BS soil treatments, both an organophobic long carbon chain and hydrophilic charged groups resulted in a relatively strong sorption ability for both heavy metals and organic pollutants. In addition, the sorption ratio K, the ratio of phenol sorption amount of the modified soil to that of CK, increased initially and decreased later with the amount of phenol added, and the critical sorption ratio KC, the peak value of the sorption ratio curve plotted against the added phenol concentration, was a good index for evaluating the sorption ability of phenol in the soil. 展开更多
关键词 amphoteric surface modifying agent cadmium ion PHENOL sorption characteristics sorption ratio K
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Competition Between Two Excitation-dissociation Channels for Molecular Ions
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作者 来丽坤 张立敏 +1 位作者 杨茂萍 周丹娜 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期223-227,339,共6页
When the molecular ions XYZ+ (XY2+) are excited simultaneously from an electronic state E0 into two higher electronic states Ea and EZ with supervened dissociation or predisso- ciation, competition between the α ... When the molecular ions XYZ+ (XY2+) are excited simultaneously from an electronic state E0 into two higher electronic states Ea and EZ with supervened dissociation or predisso- ciation, competition between the α and β excitation-dissociation channels occurs. A the- oretical model is provided to deal with the competition of the two excitation-dissociation channels with more than two kinds of ionic products for XYZ+ (XY2+). Supposing that the photo-excitation rates of two states Eα and Eβ are much less than their dissociation or pre-dissociation rates, a theoretical equation can be deduced to fit the measured data, which reflects the dependence of the product branching ratios on the intensity ratios of two excitation lasers. From the fitted parameters the excitation cross section ratios are obtained. In experiment, we studied the competition between two excitation-dissociation channels of CO^2+. By measuring the dependence of the product branching ratio on the intensity ratio of two dissociation lasers and fitting the experiment data with the theoretical equation, excitation cross section ratios were deduced. 展开更多
关键词 Molecular ion Competition of two excitation channel PHOTODISSOCIATion Excitation cross section ratio
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Study of Biological Effects of Low Energy Ion Implantation on Tomato and Radish Breeding 被引量:3
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作者 梁秋霞 黄群策 +3 位作者 曹刚强 应芳卿 刘艳波 黄文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第2期254-259,共6页
Biological effects of 30 keV low energy nitrogen ion implantation on the seeds of five types of tomato and one type of radish were investigated. Results showed that low energy ions have different effects on different ... Biological effects of 30 keV low energy nitrogen ion implantation on the seeds of five types of tomato and one type of radish were investigated. Results showed that low energy ions have different effects on different vegetables. The whole dose-response curve of the germination ratio did not take on "the shape of saddle", but was a rising and falling waveform with the increase or decrease in ion implantation. In the vegetable of Solanaceae, two outstanding aberrant plants were selected from M1 of Henan No.4 tomato at a dose of 7x 1017 nitrogen ions/cm2, which had thin-leaves, long-petal and nipple tip fruit stably inherited to Mr. Furthermore the analysis of the isozyme showed that the activity of the mutant tomato seedling was distinct in quantity and color. In Raphanus sativus L., the aberrances were obvious in the mutant of radish 791 at a dose of 5×10^17 nitrogen ions/cm^2, and the weight of succulent root and the volume of growth were over twice the control's. At present, many species for breeding have been identified in the field and only stable species have been selected for the experiment of production. It is evident that the low energy ion implantation technology has clear effects on vegetables' genetic improvement. 展开更多
关键词 low energy ion germination ratio DOSE ISOZYME
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Reagent optimization for on-line simultaneous polarographic determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in the presence of anextremely large excess of Zn^(2+) 被引量:4
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作者 WANG Guo-wei YANG Chun-hua +2 位作者 ZHU Hong-qiu LI Yong-gang GUI Wei-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2199-2204,共6页
Reagents are optimized for the simultaneous determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in zinc sulfate solution, which contains an extremely large excess of Zn^(2+). First, the reagents and their d... Reagents are optimized for the simultaneous determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in zinc sulfate solution, which contains an extremely large excess of Zn^(2+). First, the reagents and their doses for the experiment are selected according to the characteristics of the zinc sulfate solution. Then, the reagent doses are optimized by analyzing the influence of reagent dose on the polarographic parameters(i.e. half-wave potential E_(1/2) and limiting diffusion current I_p). Finally, the optimization results are verified by simultaneously determining trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in the presence of an extremely large excess of Zn^(2+). The determination results indicate that the optimized reagents exhibit wide linearity, low detection limits, high accuracy and good precision for the simultaneous determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in the presence of an extremely large excess of Zn^(2+). 展开更多
关键词 on-line simultaneous determination trace polymetallic ions reagent optimization high concentration ratio
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Effect of Anode Magnetic Shield on Magnetic Field and Ion Beam in Cylindrical Hall Thruster 被引量:2
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作者 赵杰 唐德礼 +3 位作者 耿少飞 王世庆 柳建 许丽 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第1期109-112,共4页
Numerical simulation of the effect of the anode magnetic shielding on the magnetic field and ion beam in a cylindrical Hall thruster is presented. The results show that after the anode is shielded by the magnetic shie... Numerical simulation of the effect of the anode magnetic shielding on the magnetic field and ion beam in a cylindrical Hall thruster is presented. The results show that after the anode is shielded by the magnetic shield, the magnetic field lines near the anode surface are obviously convex curved, the ratio of the magnetic mirror is enhanced, the width of the positive magnetic field gradient becomes larger than that without the anode magnetic shielding, the radial magnetic field component is enhanced, and the discharge plasma turbulence is reduced as a result of keeping the original saddle field profile and the important role the other two saddle field profiles play in restricting electrons. The results of the particle in cell (PIC) numerical simulation show that both the ion number and the energy of the ion beam increase after the anode is shielded by the magnetic shield. In other words, the specific impulse of the cylindrical Hall thruster is enhanced. 展开更多
关键词 cylindrical Hall thruster anode magnetic shield magnetic field line magnetic mirror ratio saddle magnetic field profile ion beam
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