We present findings on the effect of nanometer-sized silica-based pores on the glass transition of aqueous solutions of lithium bis(trifluoromethane)sulfonimide(LiTFSI)and lithium difluorosulfimide(LiFSI),respectively...We present findings on the effect of nanometer-sized silica-based pores on the glass transition of aqueous solutions of lithium bis(trifluoromethane)sulfonimide(LiTFSI)and lithium difluorosulfimide(LiFSI),respectively.Our experimental results demonstrate a clear dependence of the confinement effect on the anion type,particularly for water-rich solutions,in which the precipitation of crystalized ice under cooling process induces the formation of freeze-concentrated phase confined between pore wall and core ice.As this liquid layer becomes thinner,the freeze-concentrated phase experiences glass transition at increasingly higher temperatures in solutions of LiTFSI.However,differently,for solutions of LiFSI and LiCl,this secondary confinement has a negligible effect on the glass transition of solutions confined wherein.These different behaviors emphasize the obvious difference in the dynamic properties’response of LiTFSI and LiFSI solutions to spatial confinement and particularly to the presence of the hydrophilic pore wall.展开更多
The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates ...The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates that rare earth nitrate obviously inhibits the production of ·O - 2 . The inhibition rate is between 28 6% and 92%. The inhibition effect increases with the increase of rare earth nitrates concentration. The distinguish dose effect relationship was observed.展开更多
Cis-trans isomerization of [9]-annulenanion（1） and its 2-fluoro-,2-chloro-and 2-bromo-derivatives（2,3 and 4,respectively） were investigated at the HF/6-31G＊ and B3LYP/6-311＋＋G＊＊ levels of theory.Cis,cis,cis,c...Cis-trans isomerization of [9]-annulenanion（1） and its 2-fluoro-,2-chloro-and 2-bromo-derivatives（2,3 and 4,respectively） were investigated at the HF/6-31G＊ and B3LYP/6-311＋＋G＊＊ levels of theory.Cis,cis,cis,cis structures appear more stable than their corresponding cis,cis,cis,trans-isomers.The relative height of energy barriers for cis-trans isomerization is：2cis 〉1cis 〉3cis〉 4cis.This trend for the reverse trans-cis isomerization follows the electronegativity of the substituent at C-2（2trans 3trans 4trans 1trans）.展开更多
The optical effects of anion adsorption on silver sol have been studied, It was found that the anion adsorption can make the absorption peak of pure silver sol shifting to longer vevelenngth, which is attributed to th...The optical effects of anion adsorption on silver sol have been studied, It was found that the anion adsorption can make the absorption peak of pure silver sol shifting to longer vevelenngth, which is attributed to the reduction of the free electron density in the surface layer of the silver particle.展开更多
In this work, we investigate the effects of thiocyanate anions on the switching and the structure of poly(Nisopropylacrylamide)(PNIPAM) brushes using a molecular theory. Our model takes into consideration the PNIPAM–...In this work, we investigate the effects of thiocyanate anions on the switching and the structure of poly(Nisopropylacrylamide)(PNIPAM) brushes using a molecular theory. Our model takes into consideration the PNIPAM–anion bonds, the electrostatic effects and their explicit coupling to the PNIPAM conformations. It is found that at low thiocyanate anion concentration, as the anion concentration of thiocyanate increases, thiocyanate anions are more associated with PNIPAM chains through the PNIPAM–anion bonds, which contributes to stronger electrostatic repulsion and leads to an increase of lower critical solution temperature(LCST). By analyzing the average volume fractions of PNIPAM brushes,it is found that the PNIPAM brush presents a plateau structure. Our results show that the thiocyanate anions promote phase segregation due to the PNIPAM–anion bonds and the electrostatic effect. According to our model, the reduction of LCST can be explained as follows: at high thiocyanate anion concentration, with the increase of thiocyanate concentration, more ion bindings occurring between thiocyanate anions and PNIPAM chains will result in the increase of the hydrophobicity of PNIPAM chains;when the increase of electrostatic repulsion is insufficient to overcome the hydrophobic interaction of PNIPAM chains, it will lead to the reduction of brush height and LCST at high thiocyanate anion concentration. Our theoretical results are consistent with the experimental observations, and provide a fundamental understanding of the effects of thiocyanate on the LCST of PNIPAM brushes.展开更多
Rita rita exposed to a concentration of 6.9 mg per liter(96-h LC_(50)of an anionic detergent, dodecylbenzene sodium sulfonate)exhibited a gradual decrease in the lipid moieties of the epi- thelial cells,club cells,and...Rita rita exposed to a concentration of 6.9 mg per liter(96-h LC_(50)of an anionic detergent, dodecylbenzene sodium sulfonate)exhibited a gradual decrease in the lipid moieties of the epi- thelial cells,club cells,and goblet mucous cells lining the gill arch and gill filament epithelium. However,in time,no reaction of any of the lipid moieties could be observed,indicating the absence of the same,using various histochemical techniques.The results are discussed in light of the mechanistic understanding of detergent action.1989 Academic Press,Inc.展开更多
Topomerization of [9] annulen anion （1） and its 2-fluoro-, 2-chloro- and 2- bromo-defivatives （2, 3 and 4, respectively） are studied at the HF/6-31G＊ and B3LYP/6-31 1＋＋G＊＊ levels of theory. The relative ease ...Topomerization of [9] annulen anion （1） and its 2-fluoro-, 2-chloro- and 2- bromo-defivatives （2, 3 and 4, respectively） are studied at the HF/6-31G＊ and B3LYP/6-31 1＋＋G＊＊ levels of theory. The relative ease of topomerization is dependent on the charge distribution and planarity of the ground state and the transition state of 9-membered rings as well as the size and electronegativity of halogen substituent. Consequently, the endo-2-halo-[9] annulen anion topomers become unstable and easily convert to related exo-topomers. Hence, according to the DFT calcu- lations, the order of topomerization energy barrier for endo = exo topomerization is lendo 〉 2endo 〉 3endo.展开更多
A CO<sub>2</sub> capture system without supercritical CO<sub>2</sub> was optimized for mixtures of hydrophobic room temperature ionic liquids (RTILs) and propanol. We tested RTILs using bis(tri...A CO<sub>2</sub> capture system without supercritical CO<sub>2</sub> was optimized for mixtures of hydrophobic room temperature ionic liquids (RTILs) and propanol. We tested RTILs using bis(trifluoromethanesulfonyl)imide, TFSI-, anion and four quaternary ammonium cations, two quaternary phosphonium cations, and one imidazolium cation. The addition of 2-propanol into the RTILs clearly promoted the capture of normal CO<sub>2</sub>(nCO<sub>2</sub>) at ambient temperature and pressure. When combined with 2-propanol, the most efficient RTILs for nCO<sub>2</sub> capture were N-butyl-N,N,N-trimethylammonium TFSI-. This enhancement of nCO<sub>2</sub> capture was not observed in RTIL mixtures with 1-propanol or in propanol mixtures containing other phosphonium- and imidazolium-based RTILs. The torsion angle of TFSI-, which was calculated using density functional theory, is thought to be related to high nCO<sub>2</sub> capture efficiently.展开更多
In the framework of density functional theory （DFT）, the electronic excitations and nonlinear optical （NLO） properties of six binuclear transition metal cluster anions with the formula of [Ch2M-（μ-Ch）2-M＇CN]^...In the framework of density functional theory （DFT）, the electronic excitations and nonlinear optical （NLO） properties of six binuclear transition metal cluster anions with the formula of [Ch2M-（μ-Ch）2-M＇CN]^2- （M = Mo, W; Ch = S, Se; M＇ = Cu, Ag） have been systemically investigated at both cases of gas phase and DMF solution. The obtained electronic absorption spectra reveal that the element replacements of metals M and ligands Ch have significant influence on the absorptions, especially on the low-lying ones. In addition, the transitions of μ-Ch→M are dominant for the low-lying excitations, whereas the transitions of M＇→M as well as Ch→M are mainly responsible for the higher excitations. The calculated molecular first and second hyperpolarizabilities present the remarkable element substitution and solvent effects. The analyses show that the transitions involving μ-Ch→M charge transfer make the critical contributions to the first hyperpolarizability t, and that the charge transfers from the moieties of MCh4 to M＇CN as well as those of μ-Ch→M and M＇→M are responsible for the second hyperpolarizability y. Moreover, the introduction of solvent leads to the results that the transitions within the moieties of MCh4 and M＇CN make larger contributions to the hyperpolarizability, especially to γ.展开更多
以月桂醇聚醚硫酸酯钠(AES)、月桂醇聚醚硫酸酯铵(AESA)为例:通过污泥耗氧速率的变化了解表面活性剂对活性污泥的抑制情况;用磁力搅拌表面曝气法代替震荡培养法测试了城镇污水处理厂的活性污泥对表面活性剂的生物降解能力;用污泥负荷表...以月桂醇聚醚硫酸酯钠(AES)、月桂醇聚醚硫酸酯铵(AESA)为例:通过污泥耗氧速率的变化了解表面活性剂对活性污泥的抑制情况;用磁力搅拌表面曝气法代替震荡培养法测试了城镇污水处理厂的活性污泥对表面活性剂的生物降解能力;用污泥负荷表征表面活性剂的初级生物降解速率,便于计算用活性污泥法处理表面活性剂至其起泡性能消失所需的时间。实验结果表明,AES、AESA浓度≥200 mg·L^(-1)时对活性污泥中部分微生物有抑制作用。当AES、AESA浓度≤100 mg·L^(-1)时,用城镇污水处理厂的活性污泥好氧处理的初级生物降解速率分别为0.06 kg AES.(kg MLSS·d)^(-1)、0.06 kg AESA.(kg MLSS·d)^(-1);用活性污泥法好氧处理20小时后的CODCr去除率分别为75.7%、79.9%;AESA的可生物降解性优于AES。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974385 and 91956101).
文摘We present findings on the effect of nanometer-sized silica-based pores on the glass transition of aqueous solutions of lithium bis(trifluoromethane)sulfonimide(LiTFSI)and lithium difluorosulfimide(LiFSI),respectively.Our experimental results demonstrate a clear dependence of the confinement effect on the anion type,particularly for water-rich solutions,in which the precipitation of crystalized ice under cooling process induces the formation of freeze-concentrated phase confined between pore wall and core ice.As this liquid layer becomes thinner,the freeze-concentrated phase experiences glass transition at increasingly higher temperatures in solutions of LiTFSI.However,differently,for solutions of LiFSI and LiCl,this secondary confinement has a negligible effect on the glass transition of solutions confined wherein.These different behaviors emphasize the obvious difference in the dynamic properties’response of LiTFSI and LiFSI solutions to spatial confinement and particularly to the presence of the hydrophilic pore wall.
文摘The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates that rare earth nitrate obviously inhibits the production of ·O - 2 . The inhibition rate is between 28 6% and 92%. The inhibition effect increases with the increase of rare earth nitrates concentration. The distinguish dose effect relationship was observed.
文摘Cis-trans isomerization of [9]-annulenanion（1） and its 2-fluoro-,2-chloro-and 2-bromo-derivatives（2,3 and 4,respectively） were investigated at the HF/6-31G＊ and B3LYP/6-311＋＋G＊＊ levels of theory.Cis,cis,cis,cis structures appear more stable than their corresponding cis,cis,cis,trans-isomers.The relative height of energy barriers for cis-trans isomerization is：2cis 〉1cis 〉3cis〉 4cis.This trend for the reverse trans-cis isomerization follows the electronegativity of the substituent at C-2（2trans 3trans 4trans 1trans）.
文摘The optical effects of anion adsorption on silver sol have been studied, It was found that the anion adsorption can make the absorption peak of pure silver sol shifting to longer vevelenngth, which is attributed to the reduction of the free electron density in the surface layer of the silver particle.
基金Project supported by the Joint Funds of Xinjiang Natural Science Foundation(Grant No.2019D01C333)the National Natural Science Foundation of China(Grant Nos.11847610 and 21764015)the National Basic Research Program of China(Grant No.2015CB857100)
文摘In this work, we investigate the effects of thiocyanate anions on the switching and the structure of poly(Nisopropylacrylamide)(PNIPAM) brushes using a molecular theory. Our model takes into consideration the PNIPAM–anion bonds, the electrostatic effects and their explicit coupling to the PNIPAM conformations. It is found that at low thiocyanate anion concentration, as the anion concentration of thiocyanate increases, thiocyanate anions are more associated with PNIPAM chains through the PNIPAM–anion bonds, which contributes to stronger electrostatic repulsion and leads to an increase of lower critical solution temperature(LCST). By analyzing the average volume fractions of PNIPAM brushes,it is found that the PNIPAM brush presents a plateau structure. Our results show that the thiocyanate anions promote phase segregation due to the PNIPAM–anion bonds and the electrostatic effect. According to our model, the reduction of LCST can be explained as follows: at high thiocyanate anion concentration, with the increase of thiocyanate concentration, more ion bindings occurring between thiocyanate anions and PNIPAM chains will result in the increase of the hydrophobicity of PNIPAM chains;when the increase of electrostatic repulsion is insufficient to overcome the hydrophobic interaction of PNIPAM chains, it will lead to the reduction of brush height and LCST at high thiocyanate anion concentration. Our theoretical results are consistent with the experimental observations, and provide a fundamental understanding of the effects of thiocyanate on the LCST of PNIPAM brushes.
文摘Rita rita exposed to a concentration of 6.9 mg per liter(96-h LC_(50)of an anionic detergent, dodecylbenzene sodium sulfonate)exhibited a gradual decrease in the lipid moieties of the epi- thelial cells,club cells,and goblet mucous cells lining the gill arch and gill filament epithelium. However,in time,no reaction of any of the lipid moieties could be observed,indicating the absence of the same,using various histochemical techniques.The results are discussed in light of the mechanistic understanding of detergent action.1989 Academic Press,Inc.
文摘Topomerization of [9] annulen anion （1） and its 2-fluoro-, 2-chloro- and 2- bromo-defivatives （2, 3 and 4, respectively） are studied at the HF/6-31G＊ and B3LYP/6-31 1＋＋G＊＊ levels of theory. The relative ease of topomerization is dependent on the charge distribution and planarity of the ground state and the transition state of 9-membered rings as well as the size and electronegativity of halogen substituent. Consequently, the endo-2-halo-[9] annulen anion topomers become unstable and easily convert to related exo-topomers. Hence, according to the DFT calcu- lations, the order of topomerization energy barrier for endo = exo topomerization is lendo 〉 2endo 〉 3endo.
文摘A CO<sub>2</sub> capture system without supercritical CO<sub>2</sub> was optimized for mixtures of hydrophobic room temperature ionic liquids (RTILs) and propanol. We tested RTILs using bis(trifluoromethanesulfonyl)imide, TFSI-, anion and four quaternary ammonium cations, two quaternary phosphonium cations, and one imidazolium cation. The addition of 2-propanol into the RTILs clearly promoted the capture of normal CO<sub>2</sub>(nCO<sub>2</sub>) at ambient temperature and pressure. When combined with 2-propanol, the most efficient RTILs for nCO<sub>2</sub> capture were N-butyl-N,N,N-trimethylammonium TFSI-. This enhancement of nCO<sub>2</sub> capture was not observed in RTIL mixtures with 1-propanol or in propanol mixtures containing other phosphonium- and imidazolium-based RTILs. The torsion angle of TFSI-, which was calculated using density functional theory, is thought to be related to high nCO<sub>2</sub> capture efficiently.
基金the National Natural Science Foundation of China (No. 20573114)Foundation of Fujian Province (No. 2006F3133)
文摘In the framework of density functional theory （DFT）, the electronic excitations and nonlinear optical （NLO） properties of six binuclear transition metal cluster anions with the formula of [Ch2M-（μ-Ch）2-M＇CN]^2- （M = Mo, W; Ch = S, Se; M＇ = Cu, Ag） have been systemically investigated at both cases of gas phase and DMF solution. The obtained electronic absorption spectra reveal that the element replacements of metals M and ligands Ch have significant influence on the absorptions, especially on the low-lying ones. In addition, the transitions of μ-Ch→M are dominant for the low-lying excitations, whereas the transitions of M＇→M as well as Ch→M are mainly responsible for the higher excitations. The calculated molecular first and second hyperpolarizabilities present the remarkable element substitution and solvent effects. The analyses show that the transitions involving μ-Ch→M charge transfer make the critical contributions to the first hyperpolarizability t, and that the charge transfers from the moieties of MCh4 to M＇CN as well as those of μ-Ch→M and M＇→M are responsible for the second hyperpolarizability y. Moreover, the introduction of solvent leads to the results that the transitions within the moieties of MCh4 and M＇CN make larger contributions to the hyperpolarizability, especially to γ.
文摘以月桂醇聚醚硫酸酯钠(AES)、月桂醇聚醚硫酸酯铵(AESA)为例:通过污泥耗氧速率的变化了解表面活性剂对活性污泥的抑制情况;用磁力搅拌表面曝气法代替震荡培养法测试了城镇污水处理厂的活性污泥对表面活性剂的生物降解能力;用污泥负荷表征表面活性剂的初级生物降解速率,便于计算用活性污泥法处理表面活性剂至其起泡性能消失所需的时间。实验结果表明,AES、AESA浓度≥200 mg·L^(-1)时对活性污泥中部分微生物有抑制作用。当AES、AESA浓度≤100 mg·L^(-1)时,用城镇污水处理厂的活性污泥好氧处理的初级生物降解速率分别为0.06 kg AES.(kg MLSS·d)^(-1)、0.06 kg AESA.(kg MLSS·d)^(-1);用活性污泥法好氧处理20小时后的CODCr去除率分别为75.7%、79.9%;AESA的可生物降解性优于AES。
