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功能离子液体水溶液吸收CO_2的研究
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作者 姚辉 焦阳 +1 位作者 刘红晶 李冬 《应用化工》 CAS CSCD 北大核心 2015年第9期1639-1642,共4页
采用自制的功能离子液体1-2-胺乙基丁基咪唑溴盐([NH2ebim]Br)、1-2-胺乙基甲基咪唑溴盐([NH2emim]Br)的水溶液作为吸收剂,进行吸收CO2的研究。考察了不同浓度的功能离子液体水溶液吸收CO2的吸收速率,温度对CO2的吸收速率的影响,不同功... 采用自制的功能离子液体1-2-胺乙基丁基咪唑溴盐([NH2ebim]Br)、1-2-胺乙基甲基咪唑溴盐([NH2emim]Br)的水溶液作为吸收剂,进行吸收CO2的研究。考察了不同浓度的功能离子液体水溶液吸收CO2的吸收速率,温度对CO2的吸收速率的影响,不同功能离子液体水溶液对吸收速率的影响,以及吸收剂的再生效率,并探讨了功能离子液体水溶液吸收CO2的机理。结果表明,功能离子液体水溶液实现了对CO2的化学吸收,吸收速率随着功能离子液体浓度和温度的增加而增加,而功能离子液体阳离子碳链长短对水溶液吸收CO2的速率影响不显著。实验中每摩尔功能离子液体吸收的CO2大于0.5 mol,其反应机理被提出。 展开更多
关键词 CO2 吸收 功能离子液体水溶 有机醇胺
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四种水溶性离子液体对斜生栅藻的急性毒性研究
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作者 卢珩俊 沈宋利 +1 位作者 鹿燕 叶涛 《化学工程与技术》 CAS 2023年第2期97-109,共13页
本文选取斜生栅藻作为模式生物,合成且研究了咪唑类离子液体系列1-丁基、1-辛基、1-十二烷基-3-甲基咪唑盐酸盐([Cnmim][Cl] (n = 4, 8, 12)) 3种咪唑类离子液体和一种由食品原料合成的离子液体邻磺酰苯甲酰亚胺胆碱([Chol]+[Sac]−)的... 本文选取斜生栅藻作为模式生物,合成且研究了咪唑类离子液体系列1-丁基、1-辛基、1-十二烷基-3-甲基咪唑盐酸盐([Cnmim][Cl] (n = 4, 8, 12)) 3种咪唑类离子液体和一种由食品原料合成的离子液体邻磺酰苯甲酰亚胺胆碱([Chol]+[Sac]−)的暴露对斜生栅藻种群生长抑制率的影响。此外,还选取了常见的无机阴、阳离子毒物作为阳性对照,比如重金属盐CuCl2∙2H2O、ZnCl2及阴离子毒物重铬酸钾,研究了斜生栅藻对有毒物质的敏感性。根据前述受试物各自剂量–效应曲线的拟合结果显示,随着咪唑类离子液体咪唑环上烃基侧链碳原子数的增加,它们对斜生栅藻种群生长的抑制效应也会相应增强,3种离子液体对斜生栅藻的EbC50-96h依次为45.62 mg/L、0.6083 mg/L和41.87 μg/L,而邻磺酰苯甲酰亚胺胆碱离子液体([Chol]+[Sac]−)对斜生栅藻种群的生长抑制效应相对较小,其EbC50-96h为13030 mg/L。后两种咪唑类离子液体对斜生栅藻的EbC50-96h比无机毒物重铬酸钾对斜生栅藻的(EbC50-96h = 1.107 mg/L)和重金属盐CuCl2∙2H2O (EbC50-96h = 1.800 mg/L)及ZnCl2 (EbC50-96h = 2.201 mg/L)低了1~2个数量级,剩下的一种则高了1个数量级。 展开更多
关键词 水溶离子液体 水生生物 斜生栅藻 急性毒性 剂量–效应关系
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氨基酸季铵离子液体水溶液的密度和黏度 被引量:5
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作者 王薪薪 唐少峰 +3 位作者 吕兴梅 周清 李谦 张锁江 《中国科学:化学》 CAS CSCD 北大核心 2014年第6期1050-1057,共8页
选用L-a-丙氨酸、L-丝氨酸和L-天冬氨酸作为目标离子液体的阴离子来源,通过目标阳离子碱盐和目标氨基酸中和反应得到了3种季铵-氨基酸类离子液体四乙铵-丙氨酸盐([N2222][Ala])、四乙铵-丝氨酸盐([N2222][Ser])和四乙铵-天冬氨酸盐... 选用L-a-丙氨酸、L-丝氨酸和L-天冬氨酸作为目标离子液体的阴离子来源,通过目标阳离子碱盐和目标氨基酸中和反应得到了3种季铵-氨基酸类离子液体四乙铵-丙氨酸盐([N2222][Ala])、四乙铵-丝氨酸盐([N2222][Ser])和四乙铵-天冬氨酸盐([N2222][Asp]),并对其结构进行了表征. 测定了离子液体[N2222][Ala]、[N2222][Ser]以及[N2222][Asp]水溶液在不同温度下的密度和黏度,计算了超额体积及黏度偏差,并对超额体积和黏度偏差进行了关联. 分析了离子液体与溶剂之间的作用形式和离子液体与水之间形成的氢键对溶液密度和黏度的影响. 展开更多
关键词 氨基酸离子液体 离子液体水溶 密度 黏度
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288.15-318.15K温度范围内离子液体[C_5mim][Pro]水溶液的体积和表面性质 被引量:3
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作者 李驰 杨宏旭 +3 位作者 刘入境 杨奇 佟静 杨家振 《物理化学学报》 SCIE CAS CSCD 北大核心 2015年第1期11-16,共6页
在288.15-318.15 K温度范围内,测定了不同浓度离子液体1-戊基-3-甲基咪唑丙酸盐([C5mim][Pro])水溶液的密度和表面张力,计算了不同温度下不同浓度的溶液热膨胀系数、表观摩尔体积和溶液等张比容;根据密度实验数据计算得到溶质表观膨胀率... 在288.15-318.15 K温度范围内,测定了不同浓度离子液体1-戊基-3-甲基咪唑丙酸盐([C5mim][Pro])水溶液的密度和表面张力,计算了不同温度下不同浓度的溶液热膨胀系数、表观摩尔体积和溶液等张比容;根据密度实验数据计算得到溶质表观膨胀率,并与Harned和Owen提供的理论方程计算结果作了比较,两者计算结果能够很好一致;另外,本文还验证了预测溶液表面张力的经验方程,用其预测溶液的表面张力,不仅与溶液表面张力实验值在误差范围内很好一致,也与用等张比容方法预测的结果一致. 展开更多
关键词 离子液体水溶 密度 表面张力 表观摩尔体积 等张比容 丙酸盐
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离子液体水溶液中2-甲基氮杂芳烃苄位C(sp^3)—H官能化反应 被引量:2
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作者 艾锋 谢宗波 +2 位作者 姜国芳 季久健 乐长高 《有机化学》 SCIE CAS CSCD 北大核心 2018年第8期2174-2181,共8页
以中性离子液体水溶液为反应介质,无需催化剂的条件下,通过2-甲基氮杂芳烃苄位C(sp^3)—H与缺电子烯烃之间的加成反应,以良好产率合成了一系列氮杂芳烃衍生物.该方法操作简单,条件温和,不仅拓展了离子液体在氮杂芳烃的C(sp^3)—H官能化... 以中性离子液体水溶液为反应介质,无需催化剂的条件下,通过2-甲基氮杂芳烃苄位C(sp^3)—H与缺电子烯烃之间的加成反应,以良好产率合成了一系列氮杂芳烃衍生物.该方法操作简单,条件温和,不仅拓展了离子液体在氮杂芳烃的C(sp^3)—H官能化反应中的应用,对绿色化学的发展也有积极的推动作用. 展开更多
关键词 离子液体水溶 缺电子烯烃 苄位C(sp^3)—H官能化 2-甲基氮杂芳烃
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浙江大学聚合物分离膜材料表界面工程团队:渗透压驱动的水溶性离子液体高效回收新方法
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作者 赵峥 《水处理技术》 CAS CSCD 北大核心 2020年第2期12-12,共1页
近日,浙江大学聚合物分离膜材料表界面工程团队通过密度泛函理论计算以及分子动力学模拟,发现与无机盐相比,离子液体具有较弱的水合作用,同时,其水溶液在临界胶束浓度下倾向于形成胶束化的聚集体。在此基础上,分别以饱和无机盐水溶液和... 近日,浙江大学聚合物分离膜材料表界面工程团队通过密度泛函理论计算以及分子动力学模拟,发现与无机盐相比,离子液体具有较弱的水合作用,同时,其水溶液在临界胶束浓度下倾向于形成胶束化的聚集体。在此基础上,分别以饱和无机盐水溶液和离子液体水溶液作为汲取液和进料液,可在半透膜的两侧形成巨大的渗透压差,驱动水分子向无机盐侧渗透,从而实现对离子液体水溶液的浓缩。 展开更多
关键词 临界胶束浓度 密度泛函理论计算 离子液体水溶 胶束化 水合作用 水溶离子 分子动力学模拟 半透膜
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系列磷酸酯水溶性离子液体在水中摩擦学行为研究 被引量:1
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作者 黄一旭 郑甘霖 +1 位作者 王宸宸 任天辉 《润滑与密封》 CAS CSCD 北大核心 2019年第10期43-48,共6页
基于分子设计的理念,将辛醇、十二醇、十八醇分别与五氧化二磷反应得到不同链长的磷酸酯,再与二乙醇胺反应制备出3种水溶性离子液体润滑添加剂。采用红外光谱分析定性确认添加剂的结构,并应用热重分析3种添加剂的热稳定性。通过四球摩... 基于分子设计的理念,将辛醇、十二醇、十八醇分别与五氧化二磷反应得到不同链长的磷酸酯,再与二乙醇胺反应制备出3种水溶性离子液体润滑添加剂。采用红外光谱分析定性确认添加剂的结构,并应用热重分析3种添加剂的热稳定性。通过四球摩擦磨损试验机评价3种添加剂在水体系中的摩擦学性能。采用扫描电子显微镜(SEM)和X射线光电子能谱(XPS)对磨损表面进行表征分析,探讨其摩擦化学机制。结果表明:3种添加剂的热分解温度较高,分别为130、165、178℃;3种添加剂均能显著提高水体系的减摩抗磨和耐极压性能,且其抗磨和耐极压性能随着链长的增加而增强,这可能与添加剂的吸附能力和反应活性有关,烷基链较长的添加剂更容易吸附在金属表面,高载荷下能更快地与金属发生反应形成边界润滑膜;添加剂在表面形成的反应膜主要由铁氧化物,磷酸铁构成;边界润滑膜的存在提高了水体系的摩擦学性能,丰富了水作为润滑介质的使用场合。 展开更多
关键词 磷酸酯 水溶离子液体 摩擦膜 XPS
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[N1111][Lys]水溶液吸收二氧化碳的机理与动力学 被引量:6
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作者 孙铖 刘凡 +2 位作者 沈丽 李素静 李伟 《高校化学工程学报》 EI CAS CSCD 北大核心 2020年第5期1135-1142,共8页
针对电厂烟气排放量大、二氧化碳分压相对较低、传统有机胺吸收剂缺陷明显等现状,利用离子液体蒸气压低、物化性质稳定且结构可控等特性,成功合成四甲基铵赖氨酸([N1111][Lys])离子液体并将其水溶液用于吸收CO2,探究其吸收性能、反应机... 针对电厂烟气排放量大、二氧化碳分压相对较低、传统有机胺吸收剂缺陷明显等现状,利用离子液体蒸气压低、物化性质稳定且结构可控等特性,成功合成四甲基铵赖氨酸([N1111][Lys])离子液体并将其水溶液用于吸收CO2,探究其吸收性能、反应机理及动力学。研究结果表明,多氨基功能化离子液体水溶液在吸收中的表现优于单氨基离子液体,[N1111][Lys]的阴离子上不同位置的氨基不会同时与CO2反应,且不会同时参与后期的水解反应。利用分子模拟技术对反应机理进行了进一步分析发现,N的电负性会影响氨基的CO2结合能力。此外,[N1111][Lys]离子液体水溶液与CO2的反应符合快速拟一级反应的假设,对应的表观活化能为23.04kJ·mol^-1。 展开更多
关键词 离子液体水溶 二氧化碳吸收 反应机理 分子模拟 动力学
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甘氨酸离子液体[C3mim][Gly]和[C4mim][Gly]水溶液的表面张力 被引量:3
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作者 佟静 孔玉霞 +2 位作者 王盼盼 代丽丽 杨家振 《中国科学:化学》 CAS CSCD 北大核心 2012年第6期776-783,939-942,共8页
本文用中和法合成了基于烷基咪唑的甘氨酸离子液体[C3mim][Gly](1-丙基-3-甲基咪唑甘氨酸离子液体)和[C4mim][Gly](1-丁基-3-甲基咪唑甘氨酸离子液体),在298.15K下,0.0400~0.5000molkg-1浓度范围内测定了不同浓度[C4mim][Gly]和[C3mim]... 本文用中和法合成了基于烷基咪唑的甘氨酸离子液体[C3mim][Gly](1-丙基-3-甲基咪唑甘氨酸离子液体)和[C4mim][Gly](1-丁基-3-甲基咪唑甘氨酸离子液体),在298.15K下,0.0400~0.5000molkg-1浓度范围内测定了不同浓度[C4mim][Gly]和[C3mim][Gly]离子液体水溶液的密度和表面张力,得到了溶液等张比容的实验值,提出了预测不同浓度溶液等张比容的经验方程,利用这个经验方程和李以圭等人提出的溶液表面张力模型,分别估算了这两种离子液体水溶液的表面张力,其估算值和实验值在误差范围内很好地吻合. 展开更多
关键词 甘氨酸 离子液体 离子液体水溶 液表面张力 等张比容
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Solvatochromic Parameters and Preferential Solvation Behavior for Binary Mixtures of 1,3-Dialkylimidazolium Ionic Liquids with Water
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作者 丁珊 魏立纲 +1 位作者 李坤兰 马英冲 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第4期497-507,I0002,共12页
Binary mixtures of 1,3-dialkylimidazolium based ionic liquids (ILs) and water were selected as solvent systems to investigate the solute-solvent and solvent-solvent interactions on the preferential solvation of solv... Binary mixtures of 1,3-dialkylimidazolium based ionic liquids (ILs) and water were selected as solvent systems to investigate the solute-solvent and solvent-solvent interactions on the preferential solvation of solvatochromic indicators at 25 ℃. Empirical solvatochromic pa- rameters, dipolarity/polarizability (π^*), hydrogen-bond donor acidity (α), hydrogen-bond acceptor basicity (β), and Reichardt's polarity parameters (ET^N) were measured from the ultraviolet-visible spectral shifts of 4-nitroaniline, 4-nitroanisole, and Reichardt's dye. The solvent properties of the IL-water mixtures were found to be influenced by IL type and IL mole fraction (XIL). All these studied systems showed the non-ideal behavior. The max- imum deviation to ideality for the solvatochromic parameters can be obtained in the XIL range from 0.i to 0.3. For most of the binary mixtures, the π^* values showed the synergistic effects instead of the ETN, α and β values. The observed synergy extent was dependent on the studied systems, such as the dye indicator and IL type. A preferential solvation model was utilized to gather information on the molecular interactions in the mixtures. The dye indicator was preferentially solvated on the following trend: IL〉IL-water complex〉water. 展开更多
关键词 Solvatochromic parameters Preferential solvation Ionic liquid WATER
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Effect of Mono- and Di-ethanolammonium Formate Ionic Liquids on the Volatility of Water, Ethanol, and Methanol 被引量:2
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作者 李雪梅 沈冲 李春喜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第10期1162-1171,共10页
Vapor pressures were measured for six binary systems containing water, ethanol, or methanol with one of the two ionic liquids(ILs) at different component concentrations and temperatures using a quasi-static ebulliomet... Vapor pressures were measured for six binary systems containing water, ethanol, or methanol with one of the two ionic liquids(ILs) at different component concentrations and temperatures using a quasi-static ebulliometer,with the ILs mono-ethanolammonium formate([HMEA][HCOO]) and di-ethanolammonium formate([HDEA][HCOO]).The vapor pressures of the IL-containing binary systems are well correlated using the NRTL model with an overall average absolute relative deviation(AARD) of 0.0062. The effect of ILs on the vapor pressure depression of solvents at 0.050 mole fraction of IL is that [HDEA][HCOO]>[HMEA][HCOO], and the vapor pressure lowering degree follows the order of water>methanol>ethanol. Further, the activity coefficients of three solvents(viz. water,ethanol, and methanol) for the binary systems {solvent(1) + IL(2)} predicted based on the fitted NRTL parameters at T 333.15 K indicate that the two ILs generate a negative deviation from Raoult's law for water and methanol and a positive deviation for ethanol to a varying degree, change the relative volatility of a solvent. [HMEA][HCOO]may be a promising entrainer to efficiently separate ethanol aqueous solutions by special rectification. 展开更多
关键词 vapor liquid equilibria ionic liquid NRTL modcl activity coefficient binary mixturc
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Orientation and Structure of Ionic Liquid Cation at Air/[bmim][BF4] Aqueous Solution Interface 被引量:1
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作者 Gang-hua Deng Xia Li +3 位作者 You-qi Guo Shi-lin Liu Zhou Lu Yuan Guo 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第5期569-575,I0004,共8页
The watermiscible room temperature ionic liquid 1butyl3methylimidazolium tetrafluorob orate ([bmim] [BF4]) is a model system for studying the interactions between ionic liquid and water molecules. In this work the o... The watermiscible room temperature ionic liquid 1butyl3methylimidazolium tetrafluorob orate ([bmim] [BF4]) is a model system for studying the interactions between ionic liquid and water molecules. In this work the orientational structure of the low concentrated aqueous solution of [bmim] [BF4] at the air/liquid interface was investigated by sum frequency gener ation vibrational spectroscopy. It has been found that at very low concentrations, the butyl chain exhibited a significant gauche defect, indicating a disordered conformation; and the cation ring oriented with a fairly small tilting angle at the surface. When the concentration increased, the cation ring tended to lie flat at the surface, and the gauche defects of the butyl chain decreased due to the intermolecular chainchain interactions and the consequent more ordered interfacial molecular arrangement. Additionally, the antisymmetric stretching mode in the PPP and SPS spectra exhibited a peak shift, showing that there exists more than one kind of orientation or chemical environment for the butyl CH3 group. These results may shed new light on understanding the surface behavior of watermiscible ionic liquids as well as the imidazolium based surfactants. 展开更多
关键词 Sum frequency generation vibratinal spectroscopy Ionic liquid Aqueous solu-tion INTERFACE ORIENTATION
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Hydrothermal Liquefaction of Wheat Straw in Sub-critical Water/Ethanol with Ionic Liquid for Bio-oil Production 被引量:2
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作者 Wang Baofeng Han Shaohua Zhang Jinjun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期81-88,共8页
Hydrothermal liquefaction of wheat straw in sub-critical water with ionic liquid was investigated in an autoclave. The product distribution at different temperatures and pressures was studied. The liquid oil and the r... Hydrothermal liquefaction of wheat straw in sub-critical water with ionic liquid was investigated in an autoclave. The product distribution at different temperatures and pressures was studied. The liquid oil and the residuals were tested by 1H NMR, FTIR and SEM techniques. The results indicated that under the same conditions, the oil yield from liquefaction of wheat straw in water/ethanol was higher than that in sub-critical water. The result also showed that under the investigated conditions, adding 1-butyl-3-methylimidazolium chloride([Bmim]Cl) could increase the total conversion and gas yield, while at the same time the yield of n-hexane insoluble fraction and the tetrahydrofuran soluble fraction was reduced. Moreover, the results also showed that upon adding [Bmim]Cl the contents of the aliphatic hydrogen and phenols in liquid oil also increased along with improved oil quality. 展开更多
关键词 wheat straw liquefaction sub-critical water ionic liquid
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Removal of mercaptans from light oils using ionic liquid–NaOH aqueous solution as extractants 被引量:1
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作者 Jianwei Li Xiang Li +1 位作者 Yan Liu Jie Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第2期171-174,共4页
The application of ionic liquids as alternatives to conventional organic solvents in the extraction process has been investigated. In the present study, fourteen species of imidazolium-based ionic liquids were added i... The application of ionic liquids as alternatives to conventional organic solvents in the extraction process has been investigated. In the present study, fourteen species of imidazolium-based ionic liquids were added into the NaOH (aq) to remove the mercaptans. The influences of anion species and cation alkyl chain length of the imidazolium-based ionic liquids on the performance of mercaptan removal from light oils have been discussed. The efficiency of extraction for mercaptans exhibited the order of [Ac]- 〉 [OH]- [Br]- 〉 [BF4]-. The longer alkyl chain imidazolium-based ionic liquids contributed to enhance desulfurization rate of l-butyl mercaptan. 100% desulfurization rate of l-butyl mercaptan was achieved by the anion of Ac- ionic liquids and NaOH (aq) at a volume ratio of 40:1 (V(oil]:Vfionic liouid)) and a short eouilibrium time within 10 min. 展开更多
关键词 ExtractionIonic liquidsNaOHLight oilMercaptan removal
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Electrical conductivities for four ternary electrolyte aqueous solutions with one or two ionic liquid components at ambient temperatures and pressure
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作者 梁倩卿 胡玉峰 岳文佳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第6期873-879,共7页
This work provides a method to explore the transport property of the electrolyte aqueous solutions with one or two ionic liquids, especially focus on their electrical conductivity. The conductivities were measured for... This work provides a method to explore the transport property of the electrolyte aqueous solutions with one or two ionic liquids, especially focus on their electrical conductivity. The conductivities were measured for the ternary systems Na Cl–[C6mim][Cl](1-hexyl-3-methylimidazolium chloride)–H2O, [C6mim][BF4]–[C6mim][Cl]–H2O,Na NO3–[C6mim][BF4](1-hexyl-3-methylimidazolium tetrafluoroborate)–H2O, and [C4mim][BF4](1-butyl-3-methylimidazolium tetrafluoroborate)–[C6mim][BF4]–H2O, and their binary subsystems NaN O3–H2O, NaC l–H2O,[C6mim][BF4]–H2O, [C6mim][Cl]–H2O, and [C4mim][BF4]–H2O, respectively. The conductivities of the ternary systems were also determined using generalized Young's rule and semi-ideal solution theory in terms of the data of their binary solutions. The comparison showed that the two simple equations provide good predictions for conductivity of mixed electrolyte solutions and the mixed ionic liquid solutions based on the conductivity of their binary subsystems. 展开更多
关键词 CONDUCTIVITY Young's rule Semi-ideal solution theory Binary system Ternary system
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Reaction between Alkaline Metal Ions and ASR Reactive Aggregate and Behavior of Na* and K* in Cement Paste Replaced by Li*
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作者 Wei Chien Wang Chih Chien Liu Chau Lee 《Journal of Civil Engineering and Architecture》 2013年第9期1056-1062,共7页
This paper studies the reaction between alkaline metal ions Li+, Na+ and K+ and ASR (alkali-silica reaction) reactive aggregates to determine whether Li+ can substitute Na+ and K+ that are unified in cement pa... This paper studies the reaction between alkaline metal ions Li+, Na+ and K+ and ASR (alkali-silica reaction) reactive aggregates to determine whether Li+ can substitute Na+ and K+ that are unified in cement paste. Reactive aggregates use meta-sandstone from eastern Taiwan and Pyrex glass. Non-reactive aggregates use siliceous sand. The results show that the dissolved amount of SiO2 is lower when the reactive aggregates are immersed in an 80 ℃1 N LiOH'H20 solution than in NaOH and KOH solutions. The reduced amounts of OH and Li+ in the solution are also higher than those in the NaOH and KOH solutions. These results reveal that reactive SiO2 can react with LiOH to form a reactant with low water solubility. When the powder of the cement paste is immersed in an 80 ℃ 1 N LiOH-H2O solution, the amounts of free Na+ and K+ in the solution are higher than those in water. The increased amount increases with the duration of immersion. The amount of Li+ in the solution also decreases with the duration of immersion. These results reveal that Li+ can substitute Na+ and K+ that are unified in cement paste, which indicates that ASR can be prevented with the existence of Li+. 展开更多
关键词 Alkali-silica reaction LITHIUM reactive aggregate paste.
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Tunable LCST-type phase behavior of [FeCl4]--based ionic liquids in water 被引量:1
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作者 Yuanchao Pei Yuan Cao +4 位作者 Yanjie Huang Xinxin Song Huiyong Wang Yuling Zhao Jianji Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第5期587-593,共7页
In this work, 16 kinds of [FeCl4]--based magnetic ionic liquids (ILs) with different cation structures have been designed and synthesized, and their structures are characterized by IR and Raman spectroscopy. Then th... In this work, 16 kinds of [FeCl4]--based magnetic ionic liquids (ILs) with different cation structures have been designed and synthesized, and their structures are characterized by IR and Raman spectroscopy. Then the lower critical solution temperature (LCST)-type phase behavior of these magnetic ILs in water is investigated as a function of concentration. It is shown that cat- ion structure, alkyl chain length and molar ratio of FeCl3/chloride IL have a significant influence on the LCST of the mixtures. The phase separation temperature can be tuned efficiently by these factors. Meanwhile, the LCST-type phase separation pro- cess is also investigated by dynamic light scattering. The results support the mechanism that the hydrogen bonds of the [Fefl4]- anion with water have been gradually disrupted to form ILs aggregates with increasing temperature. In addition, the stability of the ILs in water is also examined in some details. These LCST-type phase separation systems may have potential applications in extraction and separation techniques at room temperature. 展开更多
关键词 magnetic ionic liquids IR and Raman spectroscopy lower critical solution temperature tunable phase separation
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Ionic liquid assisted synthesis of flowerlike Cu_2O micro-nanocrystals 被引量:1
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作者 ZHAO Yang GUO LiPing +1 位作者 SUN Xin WANG JianJi 《Science China Chemistry》 SCIE EI CAS 2012年第8期1580-1586,共7页
Novel flowerlike Cu20 micro-nanocrystals were prepared by a greener reductive reaction of cupric acetate monohydrate with ethylene glycol in aqueous solutions of [C8mim]X (X = CI-, Br-, BF4-, PFr-) and [C,,mim][BF4]... Novel flowerlike Cu20 micro-nanocrystals were prepared by a greener reductive reaction of cupric acetate monohydrate with ethylene glycol in aqueous solutions of [C8mim]X (X = CI-, Br-, BF4-, PFr-) and [C,,mim][BF4] (n = 4, 6, 8). The obtained mi- crostructures of Cu2O were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR). The effects of cations, anions and concentration of the ionic liquids on the morphology of Cu20 were examined in some details. The results suggest that the formation of flowerlike Cu20 was governed by a [Csmim][BF4] controlled reductive reaction mechanism. As one of their applications, the Cu20 nanoparticles were used for the photocatalytic degradation of methylene blue in aqueous solution, and high photocatalytic activity was observed. 展开更多
关键词 CU2O flowerlike micro-nanocrystals ionic liquid structure-directing agent photocatalytic activity
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Hydrogen bonding mediated ion pairs of some aprotic ionic liquids and their structural transition in aqueous solution
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作者 Huiyong Wang Miao Liu +3 位作者 Yuling Zhao Xiaopeng Xuan Yang Zhao Jianji Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2017年第7期970-978,共9页
Ion pair speciation of ionic liquids(ILs) has an important effect on the physical and chemical properties of ILs and recognition of the structure of ion pairs in solution is essential. It has been reported that ion pa... Ion pair speciation of ionic liquids(ILs) has an important effect on the physical and chemical properties of ILs and recognition of the structure of ion pairs in solution is essential. It has been reported that ion pairs of some ILs can be formed by hydrogen bonding interactions between cations and anions of them. Considering the fact that far-IR(FIR) spectroscopy is a powerful tool in indicating the intermolecular and intramolecular hydrogen bonding, in this work, this spectroscopic technique has been combined with molecular dynamic(MD) simulation and nuclear magnetic resonance hydrogen spectroscopy(~1H NMR) to investigate ion pairs of aprotic ILs [Bmim][NO_3], [BuPy][NO_3], [Pyr_(14)][NO_3], [PP_(14)][NO_3] and [Bu-choline][NO_3] in aqueous IL mixtures. The FIR spectra have been assigned with the aid of density functional theory(DFT) calculations, and the results are used to understand the effect of cationic nature on the structure of ion pairs. It is found that contact ion pairs formed in the neat aprotic ILs by hydrogen bonding interactions between cation and anion, were still maintained in aqueous solutions up to high water mole fraction(say 0.80 for [BuPy][NO3]). When water content was increased to a critical mole fraction of water(say 0.83 for [BuPy][NO3]), the contact ion pairs could be transformed into solvent-separated ion pairs due to the formation of the hydrogen bonding between ions and water. With the further dilution of the aqueous ILs solution, the solvent-separated ion pairs was finally turned into free cations and free anions(fully hydrated cations or anions). The concentrations of the ILs at which the contact ion pairs were transformed into solvent-separated ion pairs and solvent-separated ion pairs were transformed into free ions(fully hydrated ion) were dependent on the cationic structures. These information provides direct spectral evidence for ion pair structures of the aprotic ILs in aqueous solution. MD simulation and ~1H NMR results support the conclusion drawn from FIR spectra investigations. 展开更多
关键词 ionic liquids ion pair hydrogen bonding far infrared spectroscopy solution
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