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Effect of chloride salt concentration on unconfined compression strength of cement-treated Lianyungang soft marine clay 被引量:4
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作者 章定文 曹智国 +1 位作者 范礼彬 邓永锋 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期79-83,共5页
This study aims to quantify the influence of the amount of cement and chloride salt on the unconfined compression strength (UCS) of Lianyungang marine clay. The clays with various sodium chloride salt concentrations... This study aims to quantify the influence of the amount of cement and chloride salt on the unconfined compression strength (UCS) of Lianyungang marine clay. The clays with various sodium chloride salt concentrations were prepared artificially and stabilized by ordinary Portland cement with various contents. A series of UCS tests of cement stabilized clay specimen after 28 d curing were carried out. The results indicate that the increase of salt concentration results in the decrease in the UCS of cement-treated soil. The negative effect of salt concentration on the strength of cement stabilized clay directly relates to the cement content and salt concentration. The porosity-salt concentration/cement content ratio is a fundamental parameter for assessing the UCS of cement-treated salt-rich clay. An empirical prediction model of UCS is also proposed to take into account the effect of salt concentration. The findings of this study can be referenced for the stabilization improvement of chloride slat- rich soft clay. 展开更多
关键词 soft marine clay salt concentration CEMENTATION unconfined compression strength
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Experimental Study on the Chloride Ion Concentration of Cement Pastes Prepared with Limestone Powder
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作者 ZHANG Kaijian HUANG Zeping +1 位作者 JIA Xuxiu WANG Dehui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1474-1483,共10页
To investigate the impact of limestone powder on the chloride ion concentration coefficient of cement pastes,various techniques such as scanning electron microscopy(SEM),X-ray diffraction(XRD),thermogravimetric analys... To investigate the impact of limestone powder on the chloride ion concentration coefficient of cement pastes,various techniques such as scanning electron microscopy(SEM),X-ray diffraction(XRD),thermogravimetric analysis(TGA),and mercury-porosimetry(MIP)were employed in this paper.The findings demonstrate that the creation of Friedel's salt is inversely associated with the addition of limestone powder,that is,Friedel's salt production is lessened by adding more limestone powder,however,the coefficient of chloride ion concentration initially decreased and then increased again,as does the porosity,and most likely the pore size as well.The specific surface area of limestone powder has increased,and the content of Friedel’s salt increased first and then decreased.However,the shifting trend of Friedel's salt and chloride ion concentration coefficient is in direct opposition,and the pore structure was therefore significantly enhanced.The results of this study offer robust theoretical backing for the inclusion of limestone powder in concrete and provide a positive assessment of its potential applications. 展开更多
关键词 limestone powder specific surface area CONTENT friedel's salt chloride ion concentration coefficient
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Experimental Research on Salt-out Particle Motion and Concentration Distribution in a Vortex Pump Volute 被引量:6
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作者 GAO Bo YANG Minguan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第1期53-59,共7页
The vortex pump is suitable for salt solution transportation. But the salt-out flow mechanism in the pump has not been understood fully. Salt-out layer formation and growth rate are closely related to crystal particle... The vortex pump is suitable for salt solution transportation. But the salt-out flow mechanism in the pump has not been understood fully. Salt-out layer formation and growth rate are closely related to crystal particle motion and concentration distribution. Study on the particle hydrodynamic characteristics in the pump volute becomes a key problem, because the crystal particles are mainly distributing in this zone after they enter the pump. Phase Doppler particle analyzer(PDPA) is used to measure the two-phase flow field in a model pump volute to get more understanding about the salt-out phenomenon. The crystal particle velocities are obtained in all three peripheral, radial and axial directions. Particle size and particle number density(PND) measurements are also performed in the experiment. Results are presented and discussed along the radial direction under different pump operating conditions, as well as various axial measurement positions. It is found that particle velocity gradient of peripheral component varies with the pump discharge. There is a turning point of relation between peripheral velocity component and discharge. Radial flow velocity curves look like a saddle shape and velocity magnitudes are changing greatly with the discharge. The non-equilibrium velocity feature between liquid and solid phase on this direction is also remarkable. Particles flow into the impeller at radial position R〈I, and the axial velocity component increases in this region. The particle size curve shows an open-up parabola distribution. The largest particles are distributing near the casing peripheral wall. As flow rate increases, accordingly PND increases. It also grows up in the axial-outward direction towards the suction cover. Crystal particle aggregation phenomenon can be revealed from the analysis of particle size and PND distribution, and the aggregation region is determined as well. Research results are helpful for optimal design of this kind of pump preventing salt-out. 展开更多
关键词 vortex pump salt-oat particle motion concentration distribution
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Decondensation behavior of DNA chains induced by multivalent cations at high salt concentrations:Molecular dynamics simulations and experiments
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作者 蒋杨伟 冉诗勇 +2 位作者 何林李 王向红 章林溪 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期610-618,共9页
Using molecular dynamics simulations and atomic force microscopy (AFM), we study the decondensation process of DNA chains induced by multivalent cations at high salt concentrations in the presence of short cationic ... Using molecular dynamics simulations and atomic force microscopy (AFM), we study the decondensation process of DNA chains induced by multivalent cations at high salt concentrations in the presence of short cationic chains in solutions. The typical simulation conformations of DNA chains with varying salt concentrations for multivalent cations imply that the concentration of salt cations and the valence of multivalent cations have a strong influence on the process of DNA decondensation. The DNA chains are condensed in the absence of salt or at low salt concentrations, and the compacted conformations of DNA chains become loose when a number of cations and anions are added into the solution. It is explicitly demonstrated that cations can overcompensate the bare charge of the DNA chains and weaken the attraction interactions between the DNA chains and short cationic chains at high salt concentrations. The condensation-decondensation transi- tions of DNA are also experimentally observed in mixing spermidine with X-phage DNA at different concentrations of NaCl/MgCl2 solutions. 展开更多
关键词 DNA decondensation salt concentration multivalent cations molecular dynamics simulation
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Tuning hybrid liquid/solid electrolytes by lowering Li salt concentration for lithium batteries
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作者 Wei Yang Qi-Di Wang +8 位作者 Yu Lei Zi-Pei Wan Lei Qin Wei Yu Ru-Liang Liu Deng-Yun Zhai Hong Li Bao-Hua Li Fei-Yu Kang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期488-495,共8页
Hybrid liquid/solid electrolytes(HLSEs) consisting of conventional organic liquid electrolyte(LE), polyacrylonitrile(PAN), and ceramic lithium ion conductor Li(1.5)Al(0.5)Ge(1.5)(PO4)3(LAGP) are propos... Hybrid liquid/solid electrolytes(HLSEs) consisting of conventional organic liquid electrolyte(LE), polyacrylonitrile(PAN), and ceramic lithium ion conductor Li(1.5)Al(0.5)Ge(1.5)(PO4)3(LAGP) are proposed and investigated. The HLSE has a high ionic conductivity of over 2.25 × 10^(-3) S/cm at 25?C, and an extended electrochemical window of up to 4.8 V versus Li/Li+. The Li|HLSE|Li symmetric cells and Li|HLSE|Li FePO4 cells exhibit small interfacial area specific resistances(ASRs) comparable to that of LE while much smaller than that of ceramic LAGP electrolyte, and excellent performance at room temperature. Bis(trifluoromethane sulfonimide) salt in HLSE significantly affects the properties and electrochemical behaviors. Side reactions can be effectively suppressed by lowering the concentration of Li salt. It is a feasible strategy for pursuing the high energy density batteries with higher safety. 展开更多
关键词 lithium battery hybrid liquid/solid electrolyte interfacial resistance salt concentration
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The Effects of Rotation and Salt Concentration On Thermal Convection In a Linear Magneto-Fluid Layer Overlying a Porous Layer
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作者 Maram S. Al-Qurashi Abdul-Fattah K. Bukhari 《Journal of Electromagnetic Analysis and Applications》 2012年第9期367-378,共12页
A linear stability analysis is applied to a system consisting of a linear magneto-fluid layer overlying a porous layer affected by rotation and salt concentration on both layers. The flow in the fluid layer is governe... A linear stability analysis is applied to a system consisting of a linear magneto-fluid layer overlying a porous layer affected by rotation and salt concentration on both layers. The flow in the fluid layer is governed by Navier-Stokes’s equations and while governed by Darcy-Brinkman’s law in the porous medium. Numerical solutions are obtained using Legendre polynomials. These solutions are studied through two modes of instability: stationary instability and overstability when the heat and the salt concentration are effected from above and below. 展开更多
关键词 NAVIER-STOKES Equation Darcy-Brinkman Law LEGENDRE POLYNOMIALS salt concentration Vertical LINEAR Magnetic Field
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Influence of Surfactant and Salt Concentration on the Rheological Properties of Three Different Microstructures of Associative Polyelectrolytes Obtained by Solution Polymerization
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作者 Areli I. Velazquez-Garcia Gregorio Cadenas-Pliego +1 位作者 Claudia C. Rivera-Vallejo Enrique J. Jiménez-Regalado 《Journal of Modern Physics》 2014年第14期1387-1396,共10页
The rheological properties of three different microstructures of hydrophobically modified alkalisoluble polymers (telechelic, multisticker and combined) in the presence of various concentrations of anionic surfactant ... The rheological properties of three different microstructures of hydrophobically modified alkalisoluble polymers (telechelic, multisticker and combined) in the presence of various concentrations of anionic surfactant and salt (NaCl) were investigated. Associative polymers containing both ionic sites and small number of hydrophobic groups were obtained, and their thickening properties in aqueous solutions, were investigated. Solution polymerization was used for obtaining the different polymers. Relationships between hydrophobe, sodium dodecyl sulfate (SDS) and NaCl concentration are proposed. Owing to the competition between attractive hydrophobic interaction and repulsive electrostatic interactions, such hydrophobically modified polymers exhibit various rheological behaviors in aqueous solutions, depending on microstructure of polyelectrolyte, SDS and NaCl concentrations. 展开更多
关键词 POLYMERIZATION ASSOCIATIVE POLYELECTROLYTE RHEOLOGY SURFACTANT and salt concentration
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Experimental Study of Mineral Salts Concentration in Seawater
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作者 Aroussia Jaouahdou Abid Mohamed Jomaa Safi 《Journal of Food Science and Engineering》 2015年第1期44-47,共4页
Mineral salts are of great importance on the regulation of different metabolic activities of living organisms. The well-functioning of the body depends on mineral salts. These salts, existing naturally in small quanti... Mineral salts are of great importance on the regulation of different metabolic activities of living organisms. The well-functioning of the body depends on mineral salts. These salts, existing naturally in small quantity in our diverse diets (grains, legumes, fruit, tea, egg, etc.), are concentrated in seawater. In this paper, the indirect fi'eezing is used as a concentration process to recover the most of salt minerals naturally present in seawater. Freezing is known as a purification process, but this paper recovers the brine instead of the formed ice. A 3.5% salinity solution with an appropriate setup is used to recover the maximum of salt in the brine. The work aims to develop a process for freezing salt concentration on cold walls. The influence of operating parameters has highlighted the important role of the cooling ramp and stay time on the salt concentration produced. 展开更多
关键词 Mineral salts concentration FREEZING separation.
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Scaling salts removal in RO concentrates by inorganic induced method 被引量:3
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作者 杨庆峰 《化工学报》 EI CAS CSCD 北大核心 2005年第10期1912-1914,共3页
关键词 反渗透浓缩液 结垢盐类 无机诱导法 去除方式
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Concentrated dual-salt electrolytes for improving the cycling stability of lithium metal anodes 被引量:3
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作者 刘品 马强 +6 位作者 方铮 马洁 胡勇胜 周志彬 李泓 黄学杰 陈立泉 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期97-102,共6页
Lithium(Li) metal is an ideal anode material for rechargeable Li batteries, due to its high theoretical specific capacity(3860 mAh/g), low density(0.534 g/cm3), and low negative electrochemical potential(-3.040... Lithium(Li) metal is an ideal anode material for rechargeable Li batteries, due to its high theoretical specific capacity(3860 mAh/g), low density(0.534 g/cm3), and low negative electrochemical potential(-3.040 V vs. standard hydrogen electrode). In this work, the concentrated electrolytes with dual salts, composed of Li[N(SO2F)2](Li FSI) and Li[N(SO2CF3)2](Li TFSI) were studied. In this dual-salt system, the capacity retention can even be maintained at 95.7%after 100 cycles in Li|Li FePO4 cells. A Li|Li cell can be cycled at 0.5 mA/cm2 for more than 600 h, and a Li|Cu cell can be cycled at 0.5 m A/cm2 for more than 200 cycles with a high average Coulombi efficiency of 99%. These results show that the concentrated dual-salt electrolytes exhibit superior electrochemical performance and would be a promising candidate for application in rechargeable Li batteries. 展开更多
关键词 lithium metal rechargeable batteries dual-salt electrolyte concentrated electrolytes
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Influence of Calcium Sources and Concentration on the Storage Performance of Strawberry Fruit
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作者 Ijaz Akhtar Abdur Rab 《Journal of Agricultural Science and Technology(B)》 2014年第8期661-673,共13页
Chemical application after harvest is an important method to preserve strawberry fruit quality and extend shelf life. The strawberry fruits harvested at red stage were treated with three different sources of calcium, ... Chemical application after harvest is an important method to preserve strawberry fruit quality and extend shelf life. The strawberry fruits harvested at red stage were treated with three different sources of calcium, i.e., calcium nitrate, calcium gluconate and calcium chloride at calcium concentration of 0% (distilled water), 0.5%, 1.0% and 1.5%. The strawberry fruits were dipped for 30 s. The calcium sources, calcium concentration and the interaction of calcium sources and calcium concentration significantly affected the storage performance of strawberry fruits. All the three sources and concentrations were effective in decreasing the storage associated changes, i.e., weight loss, decline in marketable fruits, loss of organoleptic quality, increase in total soluble solids (TSS), decline in reducing sugars, total sugars, acidity and increase in sugar/acid ratio in strawberry fruit, thus extending the shelf life. Calcium gluconate at 1.5% calcium concentration was more effective. Treatment of strawberry fruit with 1.5% calcium from calcium gluconate source resulted in the highest number of marketable fruit (100%), extended shelf life (10 d), and total soluble solid (7.80%) with the minimum weight loss (5.45%). Calcium dips result in higher calcium concentration in strawberry fruits, which delays ripening in fruits by maintaining the structure and function of cell walls and membranes. It can be concluded that calcium gluconate at 1.5% concentration is an effective calcium treatment to retain the quality and extend the shelf life of strawberry fruit. 展开更多
关键词 CALCIUM concentrationS FRUIT PERISHABLE saltS sources storage strawberry.
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Research progress on protective coatings against molten nitrate salts for thermal energy storage in concentrating solar power plants
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作者 HOU Wenjie Maria Elena Navarro Rivero +4 位作者 PAN Jin ZOU Boyang Benjamin Grégoire Anabel Palacios DING Yulong 《Baosteel Technical Research》 CAS 2023年第4期1-16,共16页
Concentrating solar power(CSP) has garnered considerable global attention as a reliable means of generating bulk electricity, effectively addressing the intermittent nature of solar resources.The integration of molten... Concentrating solar power(CSP) has garnered considerable global attention as a reliable means of generating bulk electricity, effectively addressing the intermittent nature of solar resources.The integration of molten salt technology for thermal energy storage(TES) has further contributed to the growth of CSP plants;however, the corrosive nature of molten salts poses challenges to the durability of container materials, necessitating innovative corrosion mitigation strategies.This review summarizes scientific advancements in high-temperature anticorrosion coatings for molten nitrate salts, highlighting the key challenges and future trends.It also explores various coating types, including metallic, ceramic, and carbon-based coatings, and compares different coating deposition methods.This review emphasizes the need for durable coatings that meet long-term performance requirements and regulatory limitations, with an emphasis on carbon-based coatings and emerging nanomaterials.A combination of multiple coatings is required to achieve desirable anticorrosion properties while addressing material compatibility and cost considerations.The overall goal is to advance the manufacturing, assembly, and performance of CSP systems for increased efficiency, reliability, and durability in various applications. 展开更多
关键词 anticorrosive coating high temperature molten salt concentrated solar power thermal energy storage
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Application of annexation principle to the study of thermodynamic properties of ternary molten salts CaCl_2-MgC_2-NaCl 被引量:8
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作者 ZHANGJian 《Rare Metals》 SCIE EI CAS CSCD 2004年第3期209-213,共5页
Based on the practical basis of measured activities and phase diagrams aswell as in the light of the mass action law. the model of inseparable cations and anions of moltensalts and mattes, and the annexation principle... Based on the practical basis of measured activities and phase diagrams aswell as in the light of the mass action law. the model of inseparable cations and anions of moltensalts and mattes, and the annexation principle of two kinds of solutions in binary melts, thecalculating model of mass action concentrations of molten salts CaCl_2-MgCl_2-NaCl was formulated.The results of calculation not only agree with experimental values, but also obey the mass actionlaw, testifying that the model formulated can embody the structural characteristics of these ternarysalts, and that the model of inseparable cations and anions as well as the annexation principle oftwo kinds of solutions in binary melts are also applicable to these ternary salts. 展开更多
关键词 activity mass action law mass action concentration molten salts
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Soil microbial activity and community structure as affected by exposure to chloride and chloride-sulfate salts 被引量:3
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作者 ZHANG Qianqian Steven A WAKELIN +1 位作者 LIANG Yongchao CHU Guixin 《Journal of Arid Land》 SCIE CSCD 2018年第5期737-749,共13页
Mixed or chloride salty ions dominate in saline soils, and exert wide-ranging adversely affect on soil biological processes and soil functions. The objectives of this study were to(1) explore the impacts of mixed(0... Mixed or chloride salty ions dominate in saline soils, and exert wide-ranging adversely affect on soil biological processes and soil functions. The objectives of this study were to(1) explore the impacts of mixed(0, 3, 6, 10, 20 and 40 g Cl–/SO42–salt/kg dry soil) and chloride(0, 1.5, 3, 5, 8 and 15 g Cl– salt/kg dry soil) salts on soil enzyme activities, soil physiological functional(Biolog) profiles and microbial community structure by using soil enzymatic, Biolog-Eco microplates as well as denaturing gradient gel electrophoresis(DEEG) methods, and(2) determine the threshold concentration of soil electronic conductivity(EC1:5) on maintaining the functional and structural diversity of soil microbial community. The addition of either Cl– or mixed Cl–/SO42–salt obviously increased soil EC, but adversely affected soil biological activities including soil invertase activity, soil microbial biomass carbon(MBC) and substrate-induced respiration(SIR). Cl– salt showed a greater deleterious influence than mixed Cl–/SO42–salt on soil enzymes and MBC, e.g., the higher soil MBC consistently appeared with Cl–/SO42–instead of Cl– treated soil. Meanwhile, we found that SIR was more reliable than soil basal respiration(SBR) on explaining the changes of soil biological activity responsive to salt disturbance. In addition, microbial community structures of the soil bacteria, fungi, and Bacillus were obviously affected by both salt types and soil EC levels, and its diversity increased with increasing of mixed Cl–/SO42–salt rates, and then sharply declined down after it reached critical point. Moreover, the diversity of fungal community was more sensitive to the mixed salt addition than other groups. The response of soil physiological profiles(Biolog) followed a dose-response pattern with Cl–(R2=0.83) or mixed Cl–/SO42–(R2=0.89) salt. The critical threshold concentrations of salts for soil physiological function were 0.45 d S/m for Cl– and 1.26 d S/m for Cl–/SO42–, and those for soil microbial community structural diversity were 0.70 d S/m for Cl– and 1.75 d S/m for Cl–/SO42–. 展开更多
关键词 soil biological activity microbial diversit3T chloride salt mixed salt threshold concentration
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Salt transport in polymeric pervaporation membrane 被引量:2
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作者 Dihua Wu Aoran Gao Xianshe Feng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期758-765,共8页
The salt transport in a PEBA membrane used in pervaporative desalination was studied.The concentration profile of salt in the membrane during pervaporation was investigated experimentally using a multilayer membrane.T... The salt transport in a PEBA membrane used in pervaporative desalination was studied.The concentration profile of salt in the membrane during pervaporation was investigated experimentally using a multilayer membrane.The salt was found to be sorbed in the membrane but was not removed during the pervaporative desalination process,and the salt concentration in the membrane varied linearly with position.High purity water was obtained as the permeate as long as the permeate side was kept dry under vacuum.The accumulated salt uptake in the membrane follows the order of MgCl2 N NaCl N Na2 SO4.The solubility of salt in the membrane follows the order of MgCl2 N NaCl N Na2 SO4.Both the permeability and diffusivity of salt in the membrane follow the order of NaCl N MgCl2 N Na2 SO4.The permeability of salt in the membrane is not influenced by the feed salt concentration.It is mainly determined by the diffusion coefficients. 展开更多
关键词 concentration profile Pervaporative desalination salt transport
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RESALT技术在燃煤电厂脱硫废水浓缩处理中的应用 被引量:7
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作者 晋银佳 刘泽宇 +2 位作者 尤良洲 夏守庆 唐国瑞 《中国电力》 CSCD 北大核心 2019年第7期154-160,共7页
基于电渗析技术的离子重组技术(简称RESALT技术)能够将废水中的钙离子和硫酸根离子分开,因而可避免形成硫酸钙垢,同时可实现废水的浓缩减量。在华电莱州发电有限公司现场进行了脱硫废水处理量为3~4m^3/h规模的RESALT技术中试研究。脱硫... 基于电渗析技术的离子重组技术(简称RESALT技术)能够将废水中的钙离子和硫酸根离子分开,因而可避免形成硫酸钙垢,同时可实现废水的浓缩减量。在华电莱州发电有限公司现场进行了脱硫废水处理量为3~4m^3/h规模的RESALT技术中试研究。脱硫废水在RESALT装置中的运行结果表明,利用RESALT技术能够实现硫酸根离子和钙离子的有效分离,并且同时可实现含盐废水的浓缩处理,RESALT装置运行的电耗成本随进水含盐量及浓水含盐量的升高而升高,系统运行无须加药软化预处理,运行的成本主要为电费;以硫酸根、钙离子、镁离子、氯离子、钠离子质量浓度分别为6480mg/L、1820mg/L、2462mg/L、20680mg/L、10465mg/L的脱硫废水为例,系统回收率为70%,水处理电耗总计为49.5kWh/t,水处理直接成本为22.6元/t。 展开更多
关键词 燃煤电厂 高盐废水 脱硫废水 浓缩减量 REsalt技术
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Theoretical Study on Effects of Salt and Temperature on Denaturation Transition of Double-stranded DNA
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作者 DONGRui-Xin YANXun-Ling +2 位作者 PANGXiao-Feng JIANGShan LIUSheng-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期465-469,共5页
We investigate the statistical mechanics properties of a nonlinear dynamics model of the denaturation of the DNA double-helix and study the effects of salt concentration and temperature on denaturation transition of D... We investigate the statistical mechanics properties of a nonlinear dynamics model of the denaturation of the DNA double-helix and study the effects of salt concentration and temperature on denaturation transition of DNA. The specific heat, entropy, and denaturation temperature of the system versus salt concentration are obtained. These results show that the denaturation of DNA not only depends on the temperature but also is influenced by the salt concentration in the solution of DNA, which are in agreement with experimental measurement. 展开更多
关键词 DNA DENATURATION salt concentration
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Iodized salt consumption and iodine deficiency status in China: a cross-sectional study
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作者 Lijun Fan Xiaohui Su +8 位作者 Hongmei Shen Peng Liu Fangang Meng Jun Yan Zhenglong Lei Shubin Zhang Yunyou Gu Shoujun Liu Dianjun Sun 《Global Health Journal》 2017年第2期23-37,共15页
Objective:To monitor iodized salt consumption and evaluate iodine deficiency status in 2014 in China.Materials and Methods:In 2014,a nationwide cross-sectional survey was conducted in 31 provinces (in this study,provi... Objective:To monitor iodized salt consumption and evaluate iodine deficiency status in 2014 in China.Materials and Methods:In 2014,a nationwide cross-sectional survey was conducted in 31 provinces (in this study,provinces,autonomous regions and municipalities in China's Mainland were named as provinces).Probability proportional to size sampling method was adopted to recruit children ages 8-10 and pregnant women.47,467 children's and 18,994 pregnant women's urine samples were collected and 47,706 children's thyroid volumes were examined.Iodine content in salt was determined with 46,900 edible salt samples from children's households;urinary iodine concentration (UIC) was tested from children and pregnant women's urine samples;thyroid volume of children was assessed by ultrasound.Results:The national coverage rate of iodized salt and consumption rate of qualified iodized salt were 96.3% and 91.5%,respectively.Median iodine content in iodized salt was 25.2 mg/kg.In 22 of 31 provinces,the provincial coverage rates of iodized salt were over 95%.And consumption rates of qualified iodized salt were more than 90% in 21 provinces.In this study,the national median urinary iodine concentration (MUIC) of children in China was 197.9 μg/L.At the provincial level,MUIC of children in 19 provinces was 100-199 μg/L,which in 12 provinces was 200-299 μg/L.The national MUIC of pregnant women in 2014 was 154.6 μg/L,slightly higher than the lower limit of the WHO criteria for adequate (150-249 μg/L).At the provincial level,MUIC of pregnant women in 18 provinces was 100-149 μg/L,which in 13 provinces was 150-249 μg/L.The national prevalence of goiter among children in 2014 was 2.6%,of which only Shandong province (5.6%) exceeded the national standard (5%).Conclusions:In China,iodine deficiency disorders (IDD) has been eliminated since 2005.And in 2014,the IDD-free status still remained. 展开更多
关键词 iodized salt median urinary IODINE concentration prevalence of GOITER IODINE deficiency disorders the seventh national survey the coverage RATE of iodized salt CONSUMPTION RATE of QUALIFIED iodized salt
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Overview of Concentrated Solar Power
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作者 Chukwubuikem Chukwuka Komla Agbenyo Folly 《Journal of Energy and Power Engineering》 2013年第12期2291-2299,共9页
CSP (concentrated solar power) has been viewed as the technology that if properly developed could lead to a large scale conversion of solar energy into electricity. CSP is a type of solar energy converter that is cl... CSP (concentrated solar power) has been viewed as the technology that if properly developed could lead to a large scale conversion of solar energy into electricity. CSP is a type of solar energy converter that is classified as thermal converter because the output power produced is a function of the operating temperature. The main components of a CSP plant are the solar field which is made up of the heliostat arrays, the receiver tower, the heat transfer fluid, the molten salt thermal energy storage tanks and the power conversion unit, which is made up of the turbine and the generator. The main advantage of CSP is that of a cheap thermal storage (i.e., molten salt storage) which makes it possible to dispatch power at a cost comparable to the grid electricity. Simulations run with the SAM (systems advisory model) developed by NREL (National Renewable Energy Laboratory) showed that CSP is capable of delivering electricity at the cost of 17UScents per kWh for the 30-year life of the plant. The main disadvantage of CSP however, is that of low efficiency (8%-16%). There are ongoing research works to improve the efficiency of the CSP. One way to improve the efficiency is to increase the operating temperature of the system. In this paper, the authors discussed different modules of the CSP plant and suggested ways to improve on the conversion efficiencies of individual modules. Finally, an overall systems performance simulation is carried using SAM and the simulation results show that electricity can be produced using CSP at the cost of RI.05 per kWh. 展开更多
关键词 concentrated solar power HELIOSTAT molten salt energy storage SAM (systems advisory model) LCOE (levelised cost ofelectricity) blackbody receiver/emitter.
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Effects of Salt Stress on Proline Accumulation in Relation to Osmotic Adjustment in the Seedling of Elymus Dahuricus Turcz
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作者 李晓菲 《科技视界》 2013年第31期77-77,170,共2页
We investigated the effects of salt stress on proline accumulation in the seedling of Elymus dahuricus Turcz. from two different geographic regions in order to explicit various adaptability in response to salt stress ... We investigated the effects of salt stress on proline accumulation in the seedling of Elymus dahuricus Turcz. from two different geographic regions in order to explicit various adaptability in response to salt stress condition. Plants were dealt with in five salt treatments(0%, 0.5%, 1%, 2%, 3%). Significant differences were obvious at the highest salinity treatments for almost each considered parameters. Given that proline concentration is closely related to salt tolerance, we found that G2 seemed to be more tolerant. Furthermore, the proline concentration might be exploited as a dependable measure for evaluating the effect of considering regional factors on salt tolerance. 展开更多
关键词 生态系统 生态学 全球变化 草地营养循环
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