In the present study,Fmr1 knockout mice (KO mice) were used as the model for fragile X syndrome.The results of step-through and step-down tests demonstrated that Fmr1 KO mice had shorter latencies and more error cou...In the present study,Fmr1 knockout mice (KO mice) were used as the model for fragile X syndrome.The results of step-through and step-down tests demonstrated that Fmr1 KO mice had shorter latencies and more error counts,indicating a learning and memory disorder.After treatment with 30,60,90,120,or 200 mg/kg lithium chloride,the learning and memory abilities of the Fmr1 KO mice were significantly ameliorated,in particular,the 200 mg/kg lithium chloride treatment had the most significant effect.Western blot analysis showed that lithium chloride significantly enhanced the expression of phosphorylated glycogen synthase kinase 3 beta,an inactive form of glycogen synthase kinase 3 beta,in the cerebral cortex and hippocampus of the Fmr1 KO mice.These results indicated that lithium chloride improved learning and memory in the Fmr1 KO mice,possibly by inhibiting glycogen synthase kinase 3 beta activity.展开更多
The present study analyzed the effects of ethanol extracts of scorpion on epilepsy prevention and hippocampal expression of glial fibrillary acidic protein in a lithium chloride-pilocarpine epileptic rat model. Result...The present study analyzed the effects of ethanol extracts of scorpion on epilepsy prevention and hippocampal expression of glial fibrillary acidic protein in a lithium chloride-pilocarpine epileptic rat model. Results were subsequently compared with valproic acid. Results showed gradually- increased hippocampal glial fibrillary acidic protein expression following model establishment; glial fibrillary acidic protein mRNA expression was significantly increased at 3 days, reached a peak at 7 days, and then gradually decreased thereafter. Ethanol extracts of scorpion doses of 580 and 1 160 mg/kg, as well as 120 mg/kg valproic acid, led to a decreased number of glial fibrillary acidic protein-positive cells and glial fibrillary acidic protein mRNA expression, as well as decreased seizure grades and frequency of spontaneously recurrent seizures. The effects of 1 160 mg/kg ethanol extracts of scorpion were equal to those of 120 mg/kg valproic acid. These results suggested that the anti-epileptic effect of ethanol extracts of scorpion were associated with decreased hippocampal glial fibrillary acidic protein expression in a rat model of lithium chlofide-pilocarpine induced epilepsy.展开更多
To address present concerns about thickening time and high early-strength in deepwater cementing at low temperatures when using conventional accelerators, a new type of set-accelerating admixture comprising of lithium...To address present concerns about thickening time and high early-strength in deepwater cementing at low temperatures when using conventional accelerators, a new type of set-accelerating admixture comprising of lithium chloride, aluminium hydroxide and alkaline metal chlorides, named as LS-A, was studied in this paper. Mechanism analysis and performance tests show that the accelerator LS-A accelerated the hydration of tri- and dicalcium silicates (C3S and C2S) at low-temperatures by speeding up the breakdown of the protective hydration film and shortening the hydration induction period. Therefore, LS-A could shorten the low-temperature thickening time and the transition time of critical gel strength from 48 to 240 Pa of the Class-G cement slurry, and improve the early compressive strength of set cement at low-temperatures. It exhibited better performance than calcium chloride and had no effect on the type of hydration products, which remain the same as those of neat Class-G cement, i.e. the calcium silicate gel, Ca(OH)2 crystals and a small amount of ettringite AFt crystals. LS-A provides an effective way to guarantee the safety of cementing operations, and to solve the problems of low temperature and shallow water/gas flowing faced in deepwater cementing.展开更多
BACKGROUND: Previous studies have demonstrated that scorpion venom in the scorpion can inhibit epilepsy and apoptosis. However, it remains unclear whether ethanol extracts of scorpion (EES) exhibit similar effects....BACKGROUND: Previous studies have demonstrated that scorpion venom in the scorpion can inhibit epilepsy and apoptosis. However, it remains unclear whether ethanol extracts of scorpion (EES) exhibit similar effects. OBJECTIVE: To investigate the effects of EES on hippocampal apoptosis and caspase-3 expression, and to compare the effects on sodium valproate (positive control drug) in a rat model of status epilepticus induced by lithium chloride-pilocarpine. DESIGN, TIME AND SETTING: This randomized, controlled study was conducted at the Drug Research and Development Center, Kanghong Pharmaceuticals Group, and the Department of Pathology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, China from May 2007 to April 2008. MATERIALS: EES were prepared by Huashen Pharmaceutical, China. Sodium valproate (Hunan Xiangzhong Pharmaceutical, China) and lithium chloride-pilocarpine (Sigma, USA) were also used in the present study. METHODS: From a total of 156 rats, six served as normal controls. The remaining rats were intraperitoneally injected with lithium chloride-pilocarpine to establish status epileptlcus models, and then assigned to five groups (n = 30, respectively). Animals in each group were administered drugs at 15 minutes after epileptic seizure by gavage, i.e. in the normal control and model groups, rats were treated with 1 mL/0.1 kg saline. The sodium valproate group was administered 120 mg/kg/d sodium valproate. The low-, moderate-, and high-dose EES groups received treatments of 290, 580 and 1 160 mg/kg/d EES. The dispensed concentration was 1 mL/0.1 kg. Rat seizure behavior was observed. If status epilepticus did not terminated after 1 hour, the rats were intraperitoneally administered atropine (1 mg/kg) and diazepam (10 mg/kg) to terminate seizure. These rats were continuously observed for 6 hours to ensure seizure termination. Then rats were treated with the above-mentioned drugs at 8:00 am each day until sacrifice, which took place 4 hours after drug administration. MAIN OUTCOME MEASURES: Terminal dUTP nick end labeling (TUNEL)-positive cells and caspase-3 expression were, respectively, determined by TUNEL and immunohistochemistry at 6, 24 48, and 72 hours, as well as 7 days, after status epilepticus. Behavioral changes were also measured. RESULTS: A few caspase-3-positive cells were observed. TUNEL- and caspase-3-positive ceils were mainly visible in the hippocampal CA1 and CA3 regions 6 hours following status epilepticus in the model and drug intervention groups. The number of TUNEL-positive cells reached a peak at 48 hours following status epilepticus in the sodium valproate group, as well as the moderate- and high-dose EES groups, and number of TUNEL-positive cells reached a peak at 72 hours in the model and low-dose EES groups. The number of caspase-3-positive cells reached a peak at 48 hours in each group. Following treatment of sodium valproate and EES, the number of TUNEL- and caspase-3-positive cells significantly decreased compared with the model group at various time points (P 〈 0.05). The number of TUNEL- and caspase-3-positive cells was greatest in the low-dose EES group, followed by the moderate- and high-dose EES groups. The number of TUNEL- and caspase-3-positive cells was similar between the sodium valproate and high-dose EES groups. Epileptic seizure was significantly improved in the sodium valproate group, as well as the moderate- and high-dose EES groups, compared with the model group (P〈 0.05 or P〈 0.01). Treatment with sodium valproate and high-dose EES resulted in the best outcome, although the results were similar (P 〉 0.05). CONCLUSION: A dose of 1 160 mg/kg/d EES significantly inhibited status epilepticus. This outcome corresponded to a decreased number of apoptotlc cells and caspase-3-positive cells, which was similar to sodium valproate. These results suggest that it is not necessary to extract a component from the scorpion for the treatment of epilepsy. The high dose of EES significantly inhibited epilepsy, which correlated with decreased hippocampal caspase-3 expression.展开更多
Lithium(Li)is an important energy metal in the 21st century.However,the selective recovery of Li is still a big challenge,especially from acidic solutions with multiple metal ions existence.Herein we report a new ion ...Lithium(Li)is an important energy metal in the 21st century.However,the selective recovery of Li is still a big challenge,especially from acidic solutions with multiple metal ions existence.Herein we report a new ion pair induced mechanism for selectively extracting Li^(+)from acidic chloride solutions by tributyl phosphate(TBP).It is shown that the acidity and the chloride ions in the aqueous phase have great effects on the extraction of Li^(+).The FT-IR,UV-Vis and ESI-MS experiments provide solid evidence for the formation of ion-pair complex[Li(TBP)_n(H_(2)O)_(m)]^(+)[FeCl_(4)]^(-)(n-1,2,3;m-0,1)in the organic phase,which brings about the effective and efficient extraction of Li^(+).This mechanism can overcome the Hofmeister bias and allow for the selective extraction of Li^(+) from the extremely hydrophilic chlorides.It has also been proved that the loaded Li in TBP can be effectively stripped by concentrated HCl solution with a Li/Fe separation factor>500.The understanding of the ion-pair transport mechanism is helpful for optimizing the recovery process or further advancing more efficient recovery techniques for Li from acidic liquor.展开更多
The aim of this work was to investigate the effect of lithium chloride (LiCl) on the fibre length distribution, melting temperature and the rheological characteristics of high yield pulp fibre reinforced polyamide bio...The aim of this work was to investigate the effect of lithium chloride (LiCl) on the fibre length distribution, melting temperature and the rheological characteristics of high yield pulp fibre reinforced polyamide biocomposite. The inorganic salt lithium chloride (LiCl) was used to decrease the melting and processing temperature of bio-based polyamide 11. The extrusion method and Brabender mixer approaches were used to carry out the compounding process. The densities and fibre content were found to be increased after processing using both compounding methods. The HYP fibre length distribution analysis realized using the FQA equipment showed an important fibre-length reduction after processing by both techniques. The rheological properties of HYP-reinforced net and modified bio-based polyamide 11 “PA11” (HYP/PA11) composite were investigated using a capillary rheometer. The rheological tests were performed in function of the shear rate for different temperature conditions. The low-temperature process compounding had higher shear viscosity;this was because during the process the temperature was low and the mixing and melting were induced by the high shear rate created during compounding process. Experimental test results using the extrusion process showed a steep decrease in shear viscosity with increasing shear rate, and this melt-flow characteristic corresponds to shear-thinning behavior in HYP/PA11, and this steep decrease in the melt viscosity can be associated to the hydrolyse reaction of nylon for high pulp fibre moisture content at high temperature. In addition to the low processing temperature, the melt viscosity of the biocomposite using the Brabender mixer approach increases with increasing shear rate, and this stability in the increase even at high shear rate for high pulp moisture content is associated to the presence of inorganic salt lithium chloride which creates the hydrogen bonds with pulp during the compounding process.展开更多
LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical me...LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical measurements.Effects of lithium ion content and sintering temperature on physical and electrochemical performance of LiNi0.8Co0.1Mn0.1O2 were also investigated. The results show that the sample synthesized at 750℃with 105%lithium content has fine particle sizes around 200 nm and homogenous sizes distribution.The initial discharge capacity for the powder is 184 mA·h/g between 2.7 and 4.3 V at 0.1C and room temperature.展开更多
In order to study the chloride ion transport performance in fly ash addition mortar, a new method, in which the fatigue loading and chloride diffusion are undertaken simultaneously, was developed. This method realizes...In order to study the chloride ion transport performance in fly ash addition mortar, a new method, in which the fatigue loading and chloride diffusion are undertaken simultaneously, was developed. This method realizes coupling the fatigue damage process and the process of chloride transporting of fly ash mortar. The transport performance of chloride in fly ash mortar specimens was studied under different stress levels. Moreover, the effect of fly ash content on transport performance of chloride ion in mortar was investigated. AE (Acoustic Emission) and SEM were used to acquire the damage distribution of mortar specimens under action of fatigue load. The results show that the diffusion coefficient of chloride in mortar specimens increases with stress level of fatigue loading. The addition of fly ash can mitigate the penetration of chloride ion. The results of microcmck 3D location acquired by AE, accompanied with crack characterizing from SEM, indicate that the damage degree of mortar specimen increases with stress level of fatigue loading. Furthermore, higher damage degree of mortar leads to more the chloride ion content in the sample.展开更多
Reaction kinetics of LiOH·H2O and CO2 within a closed system were studied under the adsorption of water vapor by composite silica gel of lanthanum chloride. At the reaction temperature of 273~323 K and initial C...Reaction kinetics of LiOH·H2O and CO2 within a closed system were studied under the adsorption of water vapor by composite silica gel of lanthanum chloride. At the reaction temperature of 273~323 K and initial CO2 pressures of 40~100 kPa, reaction kinetics obeyed the Erofeev model. The reaction rate decreased slightly while the initial CO2 pressure reduced. When the reaction occurred at 273~299 K, the reaction rate was so low that it was almost independent of the reaction temperature. However, as the temperature rose up to 300~323 K, LiOH·H2O dehydrated its crystal water, and both the dehydrated and reaction-generated water were evaporated from solid reactant. For the dehydration rate increased, the reaction rate also increased as the reaction temperature rose. While the temperature was higher than 323 K, the reaction apparent activation energy of LiOH·H2O and CO2, was higher than 52.5 kJ·mol-1 and close to 61.4 kJ·mol-1 of the LiOH·H2O dehydrated enthalpy variable at 298 K, in which anhydrous LiOH was the major reactant and showed the reaction characteristics of LiOH crystals.展开更多
A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the expe...A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the experiment repeatable. At the reaction temperature of 15~60 ℃ and initial CO2 pressures of 25~100 kPa, the reaction rate of anhydrous LiOH and CO2 decreased slightly with the reduction of initial CO2 pressure and the rise of reaction temperature, indicating that the reaction activation energy of LiOH and CO2 was negative and close to zero. During the middle period (1~5 min) of the isothermal reaction, the ratio of reaction efficiency was approximately the power of 0.4 to that of initial CO2 pressures. As anhydrous LiOH reacted to CO2, the solid product Li2CO3 covered on the surface of LiOH was not compact, so it did not hinder the subsequent reaction of absorbing the CO2 gas. The reaction kinetics of anhydrous LiOH and CO2 obeyed the Erofeev′s model.展开更多
An acid molten salt was formed by means of mixing 1 -methyl- 3 -ethylimidazolium chloride with AlCl3 and LiAlCl4 at ambient temperature. The solubility of LiAlCl4 in the acid molten salt was measured. Variations of sp...An acid molten salt was formed by means of mixing 1 -methyl- 3 -ethylimidazolium chloride with AlCl3 and LiAlCl4 at ambient temperature. The solubility of LiAlCl4 in the acid molten salt was measured. Variations of specific conductivity, density and kinetic viscosity of molten salt with mole ratio o f MeEtlmCl/A1lCl3/LiAlCl4 were observed. A solubility maximum of LiAlCl4 with 5 4% in molar fraction was shown at a mole ratio of AlCl43/MeEtlmCl = 1 .2. An increase in density and viscosity, and a decrease in specific conductivity were found with increasing the concentrations of LiAlCl4 and AlCl3. The dependence of specific conductivity of this acid molten salt upon temperature was found to display Vogel-Tammanm-Fucher behavior. However, Arrhenius behavior was observed at two special mole ratios of MeEtImCl/AlCl3/LiAlCl4 = 1:1.5:0.05 and 1. 1.5:0. 10. The conductivity equations of this molten salt at various compositions were constructed. The ion interaction in the acid molten salt was studied using 7Li and 27Al nuclear magnetic resonance spectroscopic methods. The effect of concentrations of LiAlCl4 and AlCl3 on the ion interaction was also discussed.展开更多
基金the National Natural Science Foundation of China,No.30870876the Natural Science Foundation of Guangdong Province,No.815101700100005+2 种基金the Science and Technology Program of Guangdong Province,No.2005B60302004,2008B030301371,2009B030801368the Traditional Chinese Medicineand Combination of Traditional Chinese and Western Medicine Program of Guangzhou,No.2008A52the Medical and Health Scientific Research Program of Guangzhou,No.2009-YB-167
文摘In the present study,Fmr1 knockout mice (KO mice) were used as the model for fragile X syndrome.The results of step-through and step-down tests demonstrated that Fmr1 KO mice had shorter latencies and more error counts,indicating a learning and memory disorder.After treatment with 30,60,90,120,or 200 mg/kg lithium chloride,the learning and memory abilities of the Fmr1 KO mice were significantly ameliorated,in particular,the 200 mg/kg lithium chloride treatment had the most significant effect.Western blot analysis showed that lithium chloride significantly enhanced the expression of phosphorylated glycogen synthase kinase 3 beta,an inactive form of glycogen synthase kinase 3 beta,in the cerebral cortex and hippocampus of the Fmr1 KO mice.These results indicated that lithium chloride improved learning and memory in the Fmr1 KO mice,possibly by inhibiting glycogen synthase kinase 3 beta activity.
基金sponsored by the National Natural Science Foundation of China, No. 30740035Key Scientific and Technological Project of Sichuan Province, No. 05SG1672
文摘The present study analyzed the effects of ethanol extracts of scorpion on epilepsy prevention and hippocampal expression of glial fibrillary acidic protein in a lithium chloride-pilocarpine epileptic rat model. Results were subsequently compared with valproic acid. Results showed gradually- increased hippocampal glial fibrillary acidic protein expression following model establishment; glial fibrillary acidic protein mRNA expression was significantly increased at 3 days, reached a peak at 7 days, and then gradually decreased thereafter. Ethanol extracts of scorpion doses of 580 and 1 160 mg/kg, as well as 120 mg/kg valproic acid, led to a decreased number of glial fibrillary acidic protein-positive cells and glial fibrillary acidic protein mRNA expression, as well as decreased seizure grades and frequency of spontaneously recurrent seizures. The effects of 1 160 mg/kg ethanol extracts of scorpion were equal to those of 120 mg/kg valproic acid. These results suggested that the anti-epileptic effect of ethanol extracts of scorpion were associated with decreased hippocampal glial fibrillary acidic protein expression in a rat model of lithium chlofide-pilocarpine induced epilepsy.
基金provided by the Ph.D.Programs Foundation of Ministry of Education of China(Grant No.20100133120004)National Major Science and TechnologyProject of China(Grant No.2009ZX05060)National High Technology Research and Development Programof China(863program,Grant No.2006AA09Z340)
文摘To address present concerns about thickening time and high early-strength in deepwater cementing at low temperatures when using conventional accelerators, a new type of set-accelerating admixture comprising of lithium chloride, aluminium hydroxide and alkaline metal chlorides, named as LS-A, was studied in this paper. Mechanism analysis and performance tests show that the accelerator LS-A accelerated the hydration of tri- and dicalcium silicates (C3S and C2S) at low-temperatures by speeding up the breakdown of the protective hydration film and shortening the hydration induction period. Therefore, LS-A could shorten the low-temperature thickening time and the transition time of critical gel strength from 48 to 240 Pa of the Class-G cement slurry, and improve the early compressive strength of set cement at low-temperatures. It exhibited better performance than calcium chloride and had no effect on the type of hydration products, which remain the same as those of neat Class-G cement, i.e. the calcium silicate gel, Ca(OH)2 crystals and a small amount of ettringite AFt crystals. LS-A provides an effective way to guarantee the safety of cementing operations, and to solve the problems of low temperature and shallow water/gas flowing faced in deepwater cementing.
基金the National Natural Science Foundation of China,No.30740035the Tackle Key Program of Sichuan Province,No.05SG1672
文摘BACKGROUND: Previous studies have demonstrated that scorpion venom in the scorpion can inhibit epilepsy and apoptosis. However, it remains unclear whether ethanol extracts of scorpion (EES) exhibit similar effects. OBJECTIVE: To investigate the effects of EES on hippocampal apoptosis and caspase-3 expression, and to compare the effects on sodium valproate (positive control drug) in a rat model of status epilepticus induced by lithium chloride-pilocarpine. DESIGN, TIME AND SETTING: This randomized, controlled study was conducted at the Drug Research and Development Center, Kanghong Pharmaceuticals Group, and the Department of Pathology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, China from May 2007 to April 2008. MATERIALS: EES were prepared by Huashen Pharmaceutical, China. Sodium valproate (Hunan Xiangzhong Pharmaceutical, China) and lithium chloride-pilocarpine (Sigma, USA) were also used in the present study. METHODS: From a total of 156 rats, six served as normal controls. The remaining rats were intraperitoneally injected with lithium chloride-pilocarpine to establish status epileptlcus models, and then assigned to five groups (n = 30, respectively). Animals in each group were administered drugs at 15 minutes after epileptic seizure by gavage, i.e. in the normal control and model groups, rats were treated with 1 mL/0.1 kg saline. The sodium valproate group was administered 120 mg/kg/d sodium valproate. The low-, moderate-, and high-dose EES groups received treatments of 290, 580 and 1 160 mg/kg/d EES. The dispensed concentration was 1 mL/0.1 kg. Rat seizure behavior was observed. If status epilepticus did not terminated after 1 hour, the rats were intraperitoneally administered atropine (1 mg/kg) and diazepam (10 mg/kg) to terminate seizure. These rats were continuously observed for 6 hours to ensure seizure termination. Then rats were treated with the above-mentioned drugs at 8:00 am each day until sacrifice, which took place 4 hours after drug administration. MAIN OUTCOME MEASURES: Terminal dUTP nick end labeling (TUNEL)-positive cells and caspase-3 expression were, respectively, determined by TUNEL and immunohistochemistry at 6, 24 48, and 72 hours, as well as 7 days, after status epilepticus. Behavioral changes were also measured. RESULTS: A few caspase-3-positive cells were observed. TUNEL- and caspase-3-positive ceils were mainly visible in the hippocampal CA1 and CA3 regions 6 hours following status epilepticus in the model and drug intervention groups. The number of TUNEL-positive cells reached a peak at 48 hours following status epilepticus in the sodium valproate group, as well as the moderate- and high-dose EES groups, and number of TUNEL-positive cells reached a peak at 72 hours in the model and low-dose EES groups. The number of caspase-3-positive cells reached a peak at 48 hours in each group. Following treatment of sodium valproate and EES, the number of TUNEL- and caspase-3-positive cells significantly decreased compared with the model group at various time points (P 〈 0.05). The number of TUNEL- and caspase-3-positive cells was greatest in the low-dose EES group, followed by the moderate- and high-dose EES groups. The number of TUNEL- and caspase-3-positive cells was similar between the sodium valproate and high-dose EES groups. Epileptic seizure was significantly improved in the sodium valproate group, as well as the moderate- and high-dose EES groups, compared with the model group (P〈 0.05 or P〈 0.01). Treatment with sodium valproate and high-dose EES resulted in the best outcome, although the results were similar (P 〉 0.05). CONCLUSION: A dose of 1 160 mg/kg/d EES significantly inhibited status epilepticus. This outcome corresponded to a decreased number of apoptotlc cells and caspase-3-positive cells, which was similar to sodium valproate. These results suggest that it is not necessary to extract a component from the scorpion for the treatment of epilepsy. The high dose of EES significantly inhibited epilepsy, which correlated with decreased hippocampal caspase-3 expression.
基金supported by the National Natural Science Foundation of China(21706257,21878180)the Shanxi Province Coal Based Low-carbon Technology Major Projects(MC2016-05)the Xiangyuan Key Technology Research Projects(2018XYSDYY-02)。
文摘Lithium(Li)is an important energy metal in the 21st century.However,the selective recovery of Li is still a big challenge,especially from acidic solutions with multiple metal ions existence.Herein we report a new ion pair induced mechanism for selectively extracting Li^(+)from acidic chloride solutions by tributyl phosphate(TBP).It is shown that the acidity and the chloride ions in the aqueous phase have great effects on the extraction of Li^(+).The FT-IR,UV-Vis and ESI-MS experiments provide solid evidence for the formation of ion-pair complex[Li(TBP)_n(H_(2)O)_(m)]^(+)[FeCl_(4)]^(-)(n-1,2,3;m-0,1)in the organic phase,which brings about the effective and efficient extraction of Li^(+).This mechanism can overcome the Hofmeister bias and allow for the selective extraction of Li^(+) from the extremely hydrophilic chlorides.It has also been proved that the loaded Li in TBP can be effectively stripped by concentrated HCl solution with a Li/Fe separation factor>500.The understanding of the ion-pair transport mechanism is helpful for optimizing the recovery process or further advancing more efficient recovery techniques for Li from acidic liquor.
文摘The aim of this work was to investigate the effect of lithium chloride (LiCl) on the fibre length distribution, melting temperature and the rheological characteristics of high yield pulp fibre reinforced polyamide biocomposite. The inorganic salt lithium chloride (LiCl) was used to decrease the melting and processing temperature of bio-based polyamide 11. The extrusion method and Brabender mixer approaches were used to carry out the compounding process. The densities and fibre content were found to be increased after processing using both compounding methods. The HYP fibre length distribution analysis realized using the FQA equipment showed an important fibre-length reduction after processing by both techniques. The rheological properties of HYP-reinforced net and modified bio-based polyamide 11 “PA11” (HYP/PA11) composite were investigated using a capillary rheometer. The rheological tests were performed in function of the shear rate for different temperature conditions. The low-temperature process compounding had higher shear viscosity;this was because during the process the temperature was low and the mixing and melting were induced by the high shear rate created during compounding process. Experimental test results using the extrusion process showed a steep decrease in shear viscosity with increasing shear rate, and this melt-flow characteristic corresponds to shear-thinning behavior in HYP/PA11, and this steep decrease in the melt viscosity can be associated to the hydrolyse reaction of nylon for high pulp fibre moisture content at high temperature. In addition to the low processing temperature, the melt viscosity of the biocomposite using the Brabender mixer approach increases with increasing shear rate, and this stability in the increase even at high shear rate for high pulp moisture content is associated to the presence of inorganic salt lithium chloride which creates the hydrogen bonds with pulp during the compounding process.
基金Project(2007CB613607)supported by National Basic Research Program of China
文摘LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical measurements.Effects of lithium ion content and sintering temperature on physical and electrochemical performance of LiNi0.8Co0.1Mn0.1O2 were also investigated. The results show that the sample synthesized at 750℃with 105%lithium content has fine particle sizes around 200 nm and homogenous sizes distribution.The initial discharge capacity for the powder is 184 mA·h/g between 2.7 and 4.3 V at 0.1C and room temperature.
基金Funded by the Scientific Research Foundation of Graduate School Southeast University(No.YBJJ1129)the National Natural Science Foundation of China(No. 51078081)the National Basic Research Program of China("973"Project)(No. 2009CB326200)
文摘In order to study the chloride ion transport performance in fly ash addition mortar, a new method, in which the fatigue loading and chloride diffusion are undertaken simultaneously, was developed. This method realizes coupling the fatigue damage process and the process of chloride transporting of fly ash mortar. The transport performance of chloride in fly ash mortar specimens was studied under different stress levels. Moreover, the effect of fly ash content on transport performance of chloride ion in mortar was investigated. AE (Acoustic Emission) and SEM were used to acquire the damage distribution of mortar specimens under action of fatigue load. The results show that the diffusion coefficient of chloride in mortar specimens increases with stress level of fatigue loading. The addition of fly ash can mitigate the penetration of chloride ion. The results of microcmck 3D location acquired by AE, accompanied with crack characterizing from SEM, indicate that the damage degree of mortar specimen increases with stress level of fatigue loading. Furthermore, higher damage degree of mortar leads to more the chloride ion content in the sample.
基金Project supported bythe Beijing Education Committee Scientific Plan Fund (KM200711417006)
文摘Reaction kinetics of LiOH·H2O and CO2 within a closed system were studied under the adsorption of water vapor by composite silica gel of lanthanum chloride. At the reaction temperature of 273~323 K and initial CO2 pressures of 40~100 kPa, reaction kinetics obeyed the Erofeev model. The reaction rate decreased slightly while the initial CO2 pressure reduced. When the reaction occurred at 273~299 K, the reaction rate was so low that it was almost independent of the reaction temperature. However, as the temperature rose up to 300~323 K, LiOH·H2O dehydrated its crystal water, and both the dehydrated and reaction-generated water were evaporated from solid reactant. For the dehydration rate increased, the reaction rate also increased as the reaction temperature rose. While the temperature was higher than 323 K, the reaction apparent activation energy of LiOH·H2O and CO2, was higher than 52.5 kJ·mol-1 and close to 61.4 kJ·mol-1 of the LiOH·H2O dehydrated enthalpy variable at 298 K, in which anhydrous LiOH was the major reactant and showed the reaction characteristics of LiOH crystals.
基金Project supported bythe Beijing Education Committee Scientific Plan Fund (KM200711417006)
文摘A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the experiment repeatable. At the reaction temperature of 15~60 ℃ and initial CO2 pressures of 25~100 kPa, the reaction rate of anhydrous LiOH and CO2 decreased slightly with the reduction of initial CO2 pressure and the rise of reaction temperature, indicating that the reaction activation energy of LiOH and CO2 was negative and close to zero. During the middle period (1~5 min) of the isothermal reaction, the ratio of reaction efficiency was approximately the power of 0.4 to that of initial CO2 pressures. As anhydrous LiOH reacted to CO2, the solid product Li2CO3 covered on the surface of LiOH was not compact, so it did not hinder the subsequent reaction of absorbing the CO2 gas. The reaction kinetics of anhydrous LiOH and CO2 obeyed the Erofeev′s model.
文摘An acid molten salt was formed by means of mixing 1 -methyl- 3 -ethylimidazolium chloride with AlCl3 and LiAlCl4 at ambient temperature. The solubility of LiAlCl4 in the acid molten salt was measured. Variations of specific conductivity, density and kinetic viscosity of molten salt with mole ratio o f MeEtlmCl/A1lCl3/LiAlCl4 were observed. A solubility maximum of LiAlCl4 with 5 4% in molar fraction was shown at a mole ratio of AlCl43/MeEtlmCl = 1 .2. An increase in density and viscosity, and a decrease in specific conductivity were found with increasing the concentrations of LiAlCl4 and AlCl3. The dependence of specific conductivity of this acid molten salt upon temperature was found to display Vogel-Tammanm-Fucher behavior. However, Arrhenius behavior was observed at two special mole ratios of MeEtImCl/AlCl3/LiAlCl4 = 1:1.5:0.05 and 1. 1.5:0. 10. The conductivity equations of this molten salt at various compositions were constructed. The ion interaction in the acid molten salt was studied using 7Li and 27Al nuclear magnetic resonance spectroscopic methods. The effect of concentrations of LiAlCl4 and AlCl3 on the ion interaction was also discussed.