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Osteocyte viability and bone density in cadmium chloride-induced osteoporosis ameliorated with Pilostigma thonningii stem bark-extracted D-3-O-methy-chiroinositol 预览
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作者 Edwin Aihanuwa Uwagie-Ero Clifford Nwabugwu Abiaezute +4 位作者 Chinaka O.Nwaehujor Theophilus Okafor Nnaji Eugene Amienwanlen Odigie Oyetunde Kazeem Ekeolu Ohiemi Benjamin Ocheja 《动物模型与实验医学(英文)》 CSCD 2019年第1期25-33,共9页
Background:T his study examined the ameliorative effect of D-3-O-m ethylchiroinositol,isolated from the stem bark of Piliostigma thonningii,on cadmium chloride-induced osteoporosis in male Wistar rats.Methods:T hirty-... Background:T his study examined the ameliorative effect of D-3-O-m ethylchiroinositol,isolated from the stem bark of Piliostigma thonningii,on cadmium chloride-induced osteoporosis in male Wistar rats.Methods:T hirty-s ix rats were assigned to three treatment groups(n=12).Group A(2 mL distilled water),group B:(2.5 mg/kg b.w.CdCl 2)and group C:(2.5 mg/kg b.w.CdCl 2 and D-3-O-methyl-chiroinositol 2 mg/kg b.w.).Bone ash,calcium,phosphate,magnesium,and zinc content,as well as bone histological changes were determined at the end of months 1,2,and 3.Results:T here were significant differences(P≤0.05)in the weight of the cervical,tibia,and femoral bones in all groups.The serum concentration of CdCl 2 was significantly different across the three groups with time.There was significant variation(P<0.005)in the mean bone ash across groups.The concentration of OH-proline was significantly different(P<0.0001)across groups.There were significant differences(P<0.0001)in bone calcium,magnesium,zinc,and phosphorus concentrations.Histology revealed high levels of bone mineralisation in the CdCl 2-treated group,indicative of osteoporosis with hypertrophied osteocytes,while the femur of Wistar rats treated with D-3-O-methyl-chiroinositol showed bone trabeculae and viable osteocytes.Conclusion:T he study concluded that D-3-O-m ethyl-c hiroinositol extract from Piliostigma thionningii stem bark ameliorated cadmium chloride-induced osteoporosis in male Wistar rats. 展开更多
关键词 cadmium chloride D-3-O-methyl-chiroinositol OSTEOCYTES OSTEOPOROSIS toxicity AMELIORATION
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Simultaneous Determination of Six Constituents in Cangbaiqutong Capsule by HPLC Wavelength Switching Technique 预览
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作者 Jing WU Hongyan LIU +1 位作者 Bo YU Zhong JIA 《药用植物研究(英文版)》 2019年第4期20-23,共4页
[Objectives] To establish a high performance liquid chromatography (HPLC) wavelength switching method for the simultaneous determination of content of six constituents (phellodendrine chloride, gentiopicrin, paeoniflo... [Objectives] To establish a high performance liquid chromatography (HPLC) wavelength switching method for the simultaneous determination of content of six constituents (phellodendrine chloride, gentiopicrin, paeoniflorin, tetrandrine, berberine hydrochloride and paeonol) in Cangbaiqutong capsules, and provide a scientific basis for the comprehensive evaluation of the quality of Cangbaiqutong capsule.[Methods] The chromatographic column of Waters XSELECT CSH-C 18 (4.6 mm × 150 mm, 5 μm), the mobile phase of acetonitrile-0.1% phosphate solution, gradient elution (0-15 min,10%-18% A;15-30 min,18%-50% A;30-35 min, 50%-10% A);the flow rate of 1.0 mL/min, wavelength switching of 284 (0-7 min, phellodendrine), 274 (7-10 min, gentiopicrin), 230 (10-14 min, paeoniflorin) and 274 nm (14-35 min, tetrandrine, berberine hydrochloride, paeonol), the injection volume of 10 μL.[Results] There was a good linear relationship between the area of chromatographic peak and the injection volume of phellodendrine chloride, gentiopicrin, paeoniflorin, tetrandrine, berberine hydrochloride and paeonol in the range of 0.150-1.504, 0.768-7.680, 1.096-10.960, 0.220-2.200, 0.296-2.956, 0.0345-0.345 μg, respectively;the average recovery rates ( n =6) were 98.3%, 99.2%, 98.8%, 98.8%, 99.1% and 98.2%, respectively;the RSD value was 1.32%, 1.46%, 1.08%, 1.31%, 1.26% and 1.21%, respectively.[Conclusions] The method can be used to determine many kinds of constituents at the same time, and the operation is simple, accurate and reproducible, and can be used for the quality control of compound Cangbaiqutong capsules. 展开更多
关键词 HPLC Cangbaiqutong CAPSULE WAVELENGTH switching Simultaneous determination Phellodendrine CHLORIDE Gentiopicrin PAEONIFLORIN TETRANDRINE Quality control
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Preparation and Properties of Polyvinyl Chloride/Carbon Nanotubes Composite
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作者 陶家顺 秦玉军 +1 位作者 ZHANG Pu 郭志新 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第3期516-520,共5页
Chemically functionalized carbon nanotubes were combined with PVC to enhance both toughness and strength by simply mixing long alkyl chain modified multi-wall carbon nanotubes (abbreviated as MWNTs) or Ester-functiona... Chemically functionalized carbon nanotubes were combined with PVC to enhance both toughness and strength by simply mixing long alkyl chain modified multi-wall carbon nanotubes (abbreviated as MWNTs) or Ester-functionalized soluble MWNTs (abbreviated as eMWNTs) with PVC in Tetrahydrofuran (THF)/Cyclohexanone (CH) solution to obtain good dispersity solution. The MWNTs modified with 1-Bromohexadecane can effectively increase the intermolecular force with PVC by hydrogen bond. The obtained nanocomposite has a regular shape with homogeneously dispersed particles. PVC/2 wt% eMWNTs has been proved to possess excellent thermal stability. The intermolecular force between eMWNTs and PVC endows the as-fabricated nanocomposite with enhanced toughness and strength, indicating that our method is promising for wide use in PVC/eMWNTs nanocomposition. 展开更多
关键词 polyvinyl CHLORIDE (PVC) TOUGHNESS and STRENGTH MWNTS
地表水中电导率与氯化物、高锰酸盐指数的相关性研究 预览
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作者 余素华 吴佳宁 《广州化工》 CAS 2019年第14期115-117,130共4页
地表水水质检测在水污染预警系统中是十分重要的环节。通过对地表水中电导率和氯化物、高锰酸盐指数相关性的数据分析,结果表明:电导率和氯化物在丰水期和枯水期均呈现出显著相关性,相关系数分别为0.8667,0.9192;电导率和高锰酸盐指数... 地表水水质检测在水污染预警系统中是十分重要的环节。通过对地表水中电导率和氯化物、高锰酸盐指数相关性的数据分析,结果表明:电导率和氯化物在丰水期和枯水期均呈现出显著相关性,相关系数分别为0.8667,0.9192;电导率和高锰酸盐指数在丰水期有相关性,相关系数为0.4483,在枯水期无相关性。根据显著性的一元线性回归方程公式,在该采样点,可推算出当电导率大于2000μs/cm左右的时候,咸潮就会出现,当电导率大于3000μs/cm左右,高锰酸盐指数的方法需改为碱性方法,同时在检测化学需氧量的过程中也需根据相关性公式,加入相应的硫酸汞来消除氯化物的干扰;在丰水期,当电导率大于400μs/cm左右,高锰酸盐指数会大于6mg/L,超过地表水质量GB3838-2002的Ⅲ类水标准。可见在地表水检测中,根据数据分析讨论电导率,氯化物和高锰酸盐指数之间的相关性十分必要,这为实验室相关项目的检测、实验室在质量控制管理方面、政府相关部门进行水质预警管理均提供了重要的参考价值。 展开更多
关键词 地表水 电导率 氯化物 高锰酸盐指数 相关性
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Passivity breakdown of 13Cr stainless steel under high chloride and CO2 environment 预览
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作者 Hui-xin Li Da-peng Li +3 位作者 Lei Zhang Ya-wen Wang Xiu-yun Wang Min-xu Lu 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第3期329-336,共8页
Herein, the effect of high chloride ion (Cl^-) concentration on the corrosion behavior and passive film breakdown of 13Cr martensitic stainless steel under CO2 environment was demonstrated. The Cl^- concentration was ... Herein, the effect of high chloride ion (Cl^-) concentration on the corrosion behavior and passive film breakdown of 13Cr martensitic stainless steel under CO2 environment was demonstrated. The Cl^- concentration was varied from 30 to 150 g/L and cyclic potentiodynamic polarization was conducted to investigate the influence of the Cl^- concentration on the corrosion potential (Ecorr), passive breakdown potential (Epit), and repassivation potential (Erep). The results of the polarization curves revealed that 13Cr stainless steel is susceptible to pitting under high Cl^- concentration. The passive breakdown potential and repassivation potential decreased with the increase of Cl^- concentration. The semiconducting behavior of the passive film was investigated by Mott-Schottky analysis and the point defect model (PDM). It was observed that the iron cation vacancies and oxygen vacancies were continuously generated by autocatalytic reactions and the higher Cl^- concentration resulted in higher vacancies in the passive film. Once the excess vacancies condensed at the metal/film interface, the passive film became locally detached from the metal, which led to the breakdown of the passive film. 展开更多
关键词 13Cr STAINLESS steel electrochemical characterization PITTING corrosion high CHLORIDE concentration PASSIVE film BREAKDOWN
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Effects of mepiquat chloride on yield and main properties of cotton seed under different plant densities 预览
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作者 ZHAO Wenqing YAN Qiang +5 位作者 YANG Hongkun YANG Xiaoni WANG Leran CHEN Binglin MENG Yali ZHOU Zhiguo 《棉花研究(英文)》 2019年第2期77-86,共10页
Background:Cottonseed oil and protein content as well as germination traits are major indicators of seed quality.However,the responses of these indicators to plant density and mepiquat chloride(MC)are still uncertain.... Background:Cottonseed oil and protein content as well as germination traits are major indicators of seed quality.However,the responses of these indicators to plant density and mepiquat chloride(MC)are still uncertain.To investigate plant density and MC effects on cotto nseed yield and main quality parameters,we con ducted a twoyear field experiment including four plant densities(1.35,2.55,3.75 and 4.95 plants·m^-2)and two closes of MC(0 and 135g·hm^-2)in Dafeng,Jiangsu Province,in 2013 and 2014.Results:The application of MC reduced plant height,fruit branch length and fruiting branch number under different plant densities,resulting in a lower and more compact plant canopy.Cottonseed yield showed a nonlinear increase as plant density increasing and achieved the highest value at 3.75 plants·m^-2,regardless of MC application.No significant interactio ns were found between plant density and MC for cotton seed yield and quality parameters.The 100-seed weight,cottonseed oil content and vigor index significantly decreased as plant density increased,while these parameters significantly increased with MC applying under different plant densities.Seed vigor index was positively correlated with 100-seed weight and seed oil con tent across different plant densities and MC treatments.Conclusions:Thus,application of MC could realize a win-win situation between cottonseed yield and main quality parameters under various densities;and plant density of 3.75 plants·m^-2 combined with 135 g·hm^-2 of MC applying is optimal for high cottonseed yield and quality in this cotton production area. 展开更多
关键词 Mepiquat chloride Plant density Cottonseed yield Oil content Seed germination
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氯盐侵蚀下结构混凝土服役寿命的可靠度分析 预览
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作者 杨绿峰 蒋琼明 《混凝土》 CAS 北大核心 2019年第6期1-4,7共5页
为了全面考虑随机因素对氯盐侵蚀下结构混凝土耐久性的影响,研究建立了氯盐环境下混凝土服役寿命分析的可靠度随机边界元法。首先基于全时域初值推进法研究建立了混凝土中氯离子随机时变扩散分析的摄动随机边界元法,进而基于正常使用极... 为了全面考虑随机因素对氯盐侵蚀下结构混凝土耐久性的影响,研究建立了氯盐环境下混凝土服役寿命分析的可靠度随机边界元法。首先基于全时域初值推进法研究建立了混凝土中氯离子随机时变扩散分析的摄动随机边界元法,进而基于正常使用极限状态建立了混凝土结构服役寿命分析的可靠度分析格式,据此研究了保护层厚度、氯离子扩散系数等随机参数对结构混凝土服役寿命的影响,克服了传统的随机边界元法的缺陷。结果表明,混凝土材料及氯盐腐蚀环境的随机性、混凝土结构几何外形所导致的二维扩散现象等对氯盐环境下混凝土结构的服役寿命具有显著影响,在耐久性设计中必须合理考虑才能保障使用寿命。 展开更多
关键词 结构混凝土 随机边界元 可靠度 氯离子 服役寿命
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Enhancements of Passive Film and Pitting Resistance in Chloride Solution for 316LX Austenitic Stainless Steel After Sn Alloying
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作者 Yuan-Yuan Yang Yuan-Yuan Liu +4 位作者 Man-Lang Cheng Nian-Wei Dai Min Sun Jin Li Yi-Ming Jiang 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第1期98-106,共9页
In the present work, the electrochemical behavior and properties of the passive film of a new Sn-alloyed 316 LX austenitic stainless steel were investigated. With the increase in Sn content in 316 LX austenitic stainl... In the present work, the electrochemical behavior and properties of the passive film of a new Sn-alloyed 316 LX austenitic stainless steel were investigated. With the increase in Sn content in 316 LX austenitic stainless steel from 0 to 0.21%, the critical pitting temperature value increased from 32.6 to 38.8 °C, and the pitting potential increased from 0.252 VSCE to 0.317 VSCE. Electrochemical impedance spectroscopy results showed that the corrosion resistance of passive film rose with the increase in Sn content, indicating a more stable passive film. The Mott–Schottky measurement revealed an n-type passive film with a decreased carrier concentration on the 316 LX austenitic stainless steel surface. The Cr, Sn2+ and Sn4+(SnO, SnOHCl or SnO2) enrichments were observed in the passive layer by X-ray photoelectron spectroscopy. The enrichment of Sn and Cr in the passive film can account for the enhanced pitting resistance of 316 LX austenitic stainless steel in chloride solution. 展开更多
关键词 AUSTENITIC stainless steel SN ALLOYING PITTING Chloride solution
含铷、铯锂云母矿的复合盐焙烧-浸出性能及机理 预览
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作者 雷祖伟 钟宏 +2 位作者 王帅 曹占芳 周梓楠 《矿产综合利用》 CAS 北大核心 2019年第3期152-156,共5页
锂被称为21世纪的战略金属,而锂云母矿是目前提锂的主要锂矿物之一。本文章对含铷、铯的锂云母矿进行了多种焙烧方式探索,研究表明,硫酸盐焙烧法对锂浸出效果明显,硫酸钠+硫酸钙组合对锂的浸出率为92.53%,氯盐焙烧法对铷、铯的浸出效果... 锂被称为21世纪的战略金属,而锂云母矿是目前提锂的主要锂矿物之一。本文章对含铷、铯的锂云母矿进行了多种焙烧方式探索,研究表明,硫酸盐焙烧法对锂浸出效果明显,硫酸钠+硫酸钙组合对锂的浸出率为92.53%,氯盐焙烧法对铷、铯的浸出效果优异,氯化钠+氯化钙组合其铷、铯浸出率分别为96.13%,94.86%。进一步试验表明,焙烧添加剂中Na^+对锂的浸出有积极效果,Ca^2+对铷、铯的浸出有提升作用。综合试验结果,以SC21(碱金属盐混合物)为焙烧添加剂,锂云母矿:SC21(质量比)=1:0.7,焙烧温度为880℃,焙烧时间为45min,此时锂、铷、铯的浸出率分别为:94.52%,92.03%及93.56%。 展开更多
关键词 锂云母 硫酸盐 氯盐 焙烧
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Simulation and visualization experiment of manganese ion diffusion and damage to gel in a porous media-gel system 预览
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作者 GU Chunyuan QIN Rongsheng +3 位作者 DI Qinfeng JIANG Fan LIU Zi’ang CHEN Huijuan 《石油勘探与开发:英文版》 2019年第2期367-373,共7页
A new visualization method for studying the damage to gel structure caused by high salinity ions is explored by using the characteristics of suppression image signal of Mn^2+ and nuclear magnetic resonance(NMR) imagin... A new visualization method for studying the damage to gel structure caused by high salinity ions is explored by using the characteristics of suppression image signal of Mn^2+ and nuclear magnetic resonance(NMR) imaging technique. The diffusion and distribution characteristics of Mn^2+ in porous media-gel system were studied based on manganese chloride static diffusion and gel flooding experiments, and the gel’s nuclear magnetic image and displacement pressure were tested. The results show that the diffusion of Mn^2+conforms to the Fick diffusion law in porous media-gel system, and the diffusion speed of Mn^2+ increases and the area of gel image decreases gradually with the increase of concentration, and the image of gel decreases faster and the pressure drop of water drive is larger in flooding experiment of manganese chloride with higher concentration. Reaction-diffusion model with the reaction of Mn^2+ with gel was established to study the concentration distribution characteristics of Mn^2+. The model is validated by comparing the results with magnetic resonance imaging(MRI) experiments and the diffusion coefficient of Mn^2+ equals 1.6 mm^2/h, and the minimum concentration of Mn^2+ to impact gel NMR image signals is 2.5 g/L. The above results show that the diffusion of Mn^2+ into the gel in the rock core inhibits the imaging signal of the gel and damages its strength, and the greater the concentration is, the greater the influence. Increase of adsorption amount of gel and reaction rate, reduction of diffusion time, and addition of ion adsorption isolator all can reduce the impact of Mn^2+ on the gel. 展开更多
关键词 profile control with GEL diffusion-reaction model MANGANESE CHLORIDE magnetic resonance imaging GEL DAMAGE visualization numerical SIMULATION
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Preparation of Ultralow Molecular Weight Poly(vinyl chloride) with Submicrometer Particles via Precipitation Polymerization
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作者 Peng Cui Chang-Tong Song +3 位作者 Xian-Hong Zhang Dong Chen Yu-Hong Ma Wan-Tai Yang 《高分子科学:英文版》 SCIE CAS CSCD 2019年第7期646-653,共8页
Poly(vinyl chloride), with ultralow molecular weight, produced by free radical polymerization either at high temperature or in the presence of chain transfer agents, is widely used as special resins and polymer proces... Poly(vinyl chloride), with ultralow molecular weight, produced by free radical polymerization either at high temperature or in the presence of chain transfer agents, is widely used as special resins and polymer process additives. This paper reports a new process, called self-stabilized precipitation polymerization, in which the polymerization of vinyl chloride monomer (VCM) is conducted in hydrocarbon diluents without addition of any suspending agent or emulsifier. The merits of this novel strategy include:(1) PVC resins with ultra-low number-average molecular weight (Mn) from 4000 to 15000, which is much lower than Mn of those prepared by conventional suspension and emulsion polymerizations,(2) sub-micrometer PVC particles with near spherical morphology, and (3) the very simple post-polymerization separation process. Under mild stirring, polymerization proceeds stably and smoothly. The influences of main process factors, such as solvents, initiator and monomer concentrations, polymerization time, and temperature on both particle morphology and Mn of the polymer products are investigated systematically. The molar ratio of-CH2-CHCl-/-CH=CH-CH2CHCl, a good indicator of structural defects, is about 1000/0.1 which means the low molecular weights do not result from chain transfer to the monomers. Then the mechanism of this polymerization is proposed. In summary, this novel polymerization technology provides a straightforward method for preparing PVC particulate products with low Mn. 展开更多
关键词 Precipitation POLYMERIZATION VINYL CHLORIDE ULTRALOW molecular WEIGHT PURE product
离子色谱法同时测定蛋白胨中氯离子、硫酸根离子、碘离子 预览
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作者 杜艳 王洋 +3 位作者 郝艳君 张宏博 张彦斌 么世英 《化学分析计量》 CAS 2019年第4期22-25,共4页
建立离子色谱法测定蛋白胨中氯离子、硫酸根离子、碘离子3种阴离子的含量。采用氢氧化钾淋洗液发生器产生的KOH溶液为流动相,进行梯度淋洗,流量为1.0mL/min。氯离子、硫酸根离子的质量浓度分别在0.5~200μg/mL范围内与色谱峰面积呈良好... 建立离子色谱法测定蛋白胨中氯离子、硫酸根离子、碘离子3种阴离子的含量。采用氢氧化钾淋洗液发生器产生的KOH溶液为流动相,进行梯度淋洗,流量为1.0mL/min。氯离子、硫酸根离子的质量浓度分别在0.5~200μg/mL范围内与色谱峰面积呈良好的线性关系,碘离子的质量浓度在0.75~50μg/mL范围内与色谱峰面积呈良好的线性,线性相关系数均不小于0.999,检出限分别为0.003,0.01,0.22μg/mL。样品加标回收率为92.94%~96.59%,测定结果的相对标准偏差为2.42%~5.70%(n=9)。该方法灵敏、高效,可用于蛋白胨中氯离子、硫酸根离子、碘离子的快速准确测定。 展开更多
关键词 离子色谱法 蛋白胨 氯离子 硫酸根离子 碘离子
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Astragaloside IV attenuates myocardial ischemia/reperfusion injury in rats via inhibition of calcium-sensing receptor-mediated apoptotic signaling pathways
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作者 Bo Yin Xu-wei Hou Mei-li Lu 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第5期599-607,共9页
Astragaloside IV (AsIV) is an active saponin extracted from Astragalus membranaceus, which has shown cardioprotective effects in a number of experimental animals. In this study we investigated the molecular mechanisms... Astragaloside IV (AsIV) is an active saponin extracted from Astragalus membranaceus, which has shown cardioprotective effects in a number of experimental animals. In this study we investigated the molecular mechanisms by which AsIV attenuated the myocardial ischemia reperfusion (MI/R)-induced injury in vitro and in vivo by focusing on calcium-sensing receptor (CaSR) and extracellular signal-regulated kinase 1/2 (ERK1/2). Rat neonatal cardiac myocytes were subjected to a hypoxia/reoxygenation (H/R) procedure in vitro, which significantly decreased the cell viability, increased lactate dehydrogenase (LDH) release, induced cardiomyocyte apoptosis, and increased [Ca^2+]i. H/R also increased the expression of CaSR and decreased ERK1/2 phosphorylation levels in H/R-exposed myocytes. Pretreatment with AsIV (60μmol/L) significantly improved the cell viability and decreased LDH release, attenuated myocyte apoptosis, decreased [Ca^2+]i and CaSR expression, and increased the ERK1/2 phosphorylation levels. The protective effects of AsIV against H/R injury were partially inhibited by co-treatment with a CaSR agonist, gadolinium chloride (GdCl3) or with a specific ERK1/2 inhibitor U0126. For in vivo studies, a rat MI/R model was established. Pre-administration of AsIV (80mg/kg every day, ig) significantly decreased the myocardium infarct size, creatine kinase-MB (CK-MB) production, serum cardiac troponin (cTnI) levels, and cardiomyocyte apoptosis in the rats with MI/R injury. The therapeutic effects of AsIV were associated with the downregulation of CaSR expression and upregulation of ERK1/2 phosphorylation in myocardial tissues. In summary, astragaloside IV attenuates myocardial I/R injury via inhibition of CaSR/ERK1/2 and the related apoptotic signaling pathways. 展开更多
关键词 ASTRAGALOSIDE IV MYOCARDIAL ISCHEMIA/REPERFUSION apoptosis calcium-sensing receptor ERK1/2 GADOLINIUM chloride U0126
Microstructure of NH4Cl-NH3-H2O System Studied by ATR-FTIR, Raman and MD Simulation 预览
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作者 LI Fei GUO Xiao-fu +1 位作者 WEI Hua-chun YUAN Jun-sheng 《盐湖研究》 CSCD 2019年第2期46-52,共7页
The solubility of ammonium chloride in aqueous ammonia decreases then increases with increasing ammonia concentrations.The molecular mechanism behind this trend is unclear.In this study,ATR-FTIR and Raman spectroscopi... The solubility of ammonium chloride in aqueous ammonia decreases then increases with increasing ammonia concentrations.The molecular mechanism behind this trend is unclear.In this study,ATR-FTIR and Raman spectroscopic techniques were used to determine the effect of ammonium chloride on hydrogen bonding in aqueous ammonia and ultimately explain the observed solubility trend.Spectral analyses were conducted in the wavelength range of 2500-4000 cm^-1 .The results showed that the addition of ammonium chloride endorses the formation of N-H…N hydrogen bonds between ammonium ions and ammonia molecules when the concentration of ammonia is greater than 10% ammonia.However,for concentrations lower than 10%,ammonium ions mainly bond to water molecules,leading to hydrogen bonds of the N-H…O type that are generally less stable than N-H…N bonds.The spectral analyses are confirmed by MD simulations.The results presented herein are useful in the development of novel techniques for the separation of ammonium potassium chloride. 展开更多
关键词 AMMONIA AMMONIUM CHLORIDE solution ATR-FTIR RAMAN MD simulation
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Isothermal Evaporating Phase Equilibria in the Quaternary System (LiCl+NaCl+Li2SO4+Na2SO4+H2O)at 348.15 K and 0.1 MPa:An Experimental and Theoretical Study 预览
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作者 GUO Ya-fei YUAN Fei +2 位作者 LI Long WANG Shi-qiang DENG Tian-long 《盐湖研究》 CSCD 2019年第2期69-77,共9页
The gradient solar pond technique is an economic separating process employed in the inorganic chemical industrial production of salt lake chemical engineering processes. In this paper, a novel isothermal evaporation e... The gradient solar pond technique is an economic separating process employed in the inorganic chemical industrial production of salt lake chemical engineering processes. In this paper, a novel isothermal evaporation experimental method was employed to simulate the evaporation phase equilibrium for the reciprocal quaternary system (LiCl+NaCl+Li2SO4+Na2SO 4+H2O) at 348.15 K to serve as a useful guide for lithium salt production via the depth solar ponds.The isothermal evaporation equilibrium solubilities and physicochemical properties,including the densities and pH values, were experimentally investigated. The dry-salt phase diagram,water-phase diagram, and the diagram of the physicochemical properties versus composition were plotted with respect to the experimental data. The dry-salt phase diagram consists of three invariant points,seven univariant solubility curves, and five crystallization regions, specifically halite(NaCl,Ha),thenardite (Na2SO4,Th),double salt (Li2SO4 · Na2SO4 , Db2), lithium sulfate monohydrate (Li2SO4 ·H2O, Ls), and lithium chloride monohydrate(LiCl·H2O, Lc). Based on Pitzer and its extended HMW model, the Pitzer single salt parameters, mixing ion interaction parameters, and thermodynamic stable equilibrium constants for the quaternary system at 348.15 K were obtained. The calculated phase diagram and experimental isothermal phase diagram at 348.15 K exhibited a great difference. Based on these results, the isothermal evaporation phase diagram can truly reflect the salt sedimentary in salt lakes and can be applied as a useful guide for the solar pond process. 展开更多
关键词 Phase DIAGRAM Solubility LITHIUM chloride LITHIUM sulfate Pitzer model
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盐湖地区RC桥梁结构时变车桥耦合振动寿命预测研究 预览
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作者 李双营 赵建昌 《振动与冲击》 EI CSCD 北大核心 2019年第12期9-16,共8页
盐湖地区氯离子侵蚀环境下,RC桥梁结构时变车桥耦合振动是一个复杂的多因素、高度非线型过程,且随着列车运行速度的增加,这种特性逐渐增强,因此,对于使用寿命评估需要更高要求的预测模型。采用二系主动悬挂系统建立RC桥梁车桥垂向耦合... 盐湖地区氯离子侵蚀环境下,RC桥梁结构时变车桥耦合振动是一个复杂的多因素、高度非线型过程,且随着列车运行速度的增加,这种特性逐渐增强,因此,对于使用寿命评估需要更高要求的预测模型。采用二系主动悬挂系统建立RC桥梁车桥垂向耦合振动模型,基于虚拟激励法,求解列车在不同运行速度时的垂向振动位移,并以该位移和能量守恒定律为条件,确定荷载影响因子f(δ)的取值。基于Fick第二扩散定律理论,充分考虑混凝土氯离子扩散系数的时间依赖性、轨道不平顺激励及高速列车运行速度对RC桥梁结构垂向振动影响等因素,得到一种既考虑荷载影响因子f(δ)又考虑氯离子结合能力的RC桥梁氯离子扩散修正模型。仿真实验结果表明,与传统的未考虑列车运行速度影响因素的氯离子扩散模型相比,所提出的RC桥梁氯离子扩散修正模型更加合理,对于盐湖地区既有RC桥梁结构使用寿命的预测将更有实际工程意义。 展开更多
关键词 盐湖地区 RC桥梁结构 氯离子 垂向振动 荷载影响因子
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氯盐侵蚀下约束混凝土力学性能试验研究
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作者 曹琛 《建筑结构》 CSCD 北大核心 2019年第12期103-108,共6页
为了解氯离子侵蚀下约束混凝土的抗压力学性能,在盐雾腐蚀实验室对12组约束混凝土试件进行氯离子腐蚀试验,进而对其进行轴心抗压试验,得到不同箍筋配箍率和不同锈胀裂缝宽度下试件的受压应力-应变曲线,分析箍筋配箍率和锈胀裂缝宽度对... 为了解氯离子侵蚀下约束混凝土的抗压力学性能,在盐雾腐蚀实验室对12组约束混凝土试件进行氯离子腐蚀试验,进而对其进行轴心抗压试验,得到不同箍筋配箍率和不同锈胀裂缝宽度下试件的受压应力-应变曲线,分析箍筋配箍率和锈胀裂缝宽度对腐蚀试件强度、刚度、延性等的影响。结果表明:随着箍筋配箍率的增大,试件的承载力和延性不断提高;随着箍筋锈蚀裂缝宽度的增大,试件的峰值荷载减小,强度降低,延性变差。并考虑箍筋锈蚀的约束作用对核心区混凝土本构关系的影响,建立了锈蚀约束混凝土受压本构关系理论模型,将其与试验数据拟合回归得到的应力-应变全曲线进行对比,两者吻合良好,故该理论模型可应用于锈蚀钢筋混凝土结构、构件的非线性分析中。 展开更多
关键词 氯离子 约束混凝土 锈蚀箍筋 轴心抗压试验 本构关系
Usher综合征患者血清离子浓度的变化 预览
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作者 代贺华 张芷萌 +4 位作者 王蕾 陶天畅 许静 李如意 李根林 《眼科新进展》 CAS 北大核心 2019年第7期645-648,共4页
目的探讨Usher综合征(Usher syndrome,USH)患者血清离子浓度的变化情况。方法选取2015年9月至2018年9月北京同仁医院眼科中心的46例临床诊断为USH患者作为USH组;同时选取同期于北京同仁医院体检中心体检的90例正常人为对照组。检测各组... 目的探讨Usher综合征(Usher syndrome,USH)患者血清离子浓度的变化情况。方法选取2015年9月至2018年9月北京同仁医院眼科中心的46例临床诊断为USH患者作为USH组;同时选取同期于北京同仁医院体检中心体检的90例正常人为对照组。检测各组受试者血清离子浓度。将USH组与对照组的各血清离子浓度进行比较。结果 USH组患者血清钙离子浓度为(2.364±0.101)mmol·L-1,高于对照组的血清钙离子浓度(2.304±0.082)mmol·L-1,差异有统计学意义(P=0.000);USH组患者钾离子浓度为(4.124±0.360)mmol·L-1,高于对照组的钾离子浓度(3.965±0.288)mmol·L-1,差异有统计学意义(P=0.006);两组间的钠离子、氯离子、无机磷离子浓度相比,差异均无统计学意义(均为P>0.05)。结论 USH患者的钙离子与钾离子浓度异常,这种异常可能与其发病有关。 展开更多
关键词 USHER综合征 血清浓度 钙离子 钾离子 钠离子 氯离子 无机磷离子
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Application of a green coagulant with PACl in efficient purification of turbid water and its mechanism study
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作者 Yuxiang Xue Zhouzhou Liu +1 位作者 Aimin Li Hu Yang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第7期168-180,共13页
The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chlo... The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chloride(PACl) were extensively evaluated for various addition sequences in the coagulation of both raw(surface water from the Jiuxiang River) and synthetic turbid water(two kaolin suspensions with different initial turbidities).Two typical cationic starch-based coagulants with different structures(St-G and St-E) were tried. In comparison to St-G, St-E and PACl used individually as well as St-G and St-E dosed after PACl, the combination of the starch-based coagulants fed before PACl showed higher turbidity removal efficiency, which featured not only less optimal doses of both inorganic and organic coagulants but also lower residual turbidity. On the basis of a detailed analysis of the particle size and its distribution in solution supernatants before and after coagulation by two starch-based coagulants and PACl, polymeric coagulants preferentially coagulate the small-sized colloids due to their distinct long-chain structures, but PACl preferentially coagulates the medium-sized ones. Thus, the medium-sized particles that were previously formed by the starch-based coagulants would be collectively and effectively removed by the subsequent addition of PACl. The addition sequence of the inorganic and organic coagulants in their combined usage is an important factor for improvement of the turbidity removal efficiency in practice. 展开更多
关键词 Cationic starch-based green COAGULANTS POLYALUMINUM chloride Combined COAGULATION SYNERGISTIC COAGULATION effects SYNERGISTIC mechanisms
离子选择电极法测定天然水中氯离子含量 预览
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作者 郝栗涛 雒昆利 +2 位作者 张湜溪 李勃 樊景森 《检验检疫学刊》 2019年第1期25-28,共4页
天然水中常量元素氯的含量与人类身体健康密切相关,快速、准确地测定水中氯含量具有重要意义。目前,实验室测定天然水中氯离子的方法为国标法GB/T 11896—1989《水质氯化物的测定基本信息硝酸银滴定法》。该方法通过硝酸银滴定法测定水... 天然水中常量元素氯的含量与人类身体健康密切相关,快速、准确地测定水中氯含量具有重要意义。目前,实验室测定天然水中氯离子的方法为国标法GB/T 11896—1989《水质氯化物的测定基本信息硝酸银滴定法》。该方法通过硝酸银滴定法测定水中氯离子。由于硝酸银滴定法依靠指示剂颜色的变化来判断滴定终点,容易造成较大检测误差。因此,为了快速、准确地测定天然水中氯离子含量,本文建立了离子选择电极法。该方法首先配制100 mg/L的氯化钠(NaCl)标准溶液,然后分别取0.5 m L、2.5 mL、5.0 m L标准溶液用以绘制标准曲线,实现天然水中氯离子的定量检测。该方法对天然水中氯离子的检测限为5.2 mg/L,测得氯离子标准溶液回收率为91.7%~101%,相对标准偏差范围为4.5%~6.4%。该方法可以准确测定天然水中的氯离子含量,且较国标法具有定量准确、操作简单、快速等优点,并且可以满足天然水中氯离子含量的测定。 展开更多
关键词 天然水 氯离子 离子选择电极法
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