Biodiesel was used to prepare epoxidized fatty acid isobutyl esters(Ep-FABEs)as a biobased plasticizer in this work.Transesterification of biodiesel with isobutanol catalyzed by tetrabutyl titanate was carried out in ...Biodiesel was used to prepare epoxidized fatty acid isobutyl esters(Ep-FABEs)as a biobased plasticizer in this work.Transesterification of biodiesel with isobutanol catalyzed by tetrabutyl titanate was carried out in a gas-liquid tower reactor.The conversion achieved nearly 100%within 5 h under the reaction temperature,the mass ratio of catalyst to fatty acid methyl esters(FAMEs),and isobutanol to FAMEs total molar ratio of 180℃,0.4%(mass),and 5.4:1,respectively.In addition,kinetic model of the transesterification reaction was developed at 150–190℃.The calculated activation energy was 48.93 kJ·mol^(-1).Then,the epoxidation of obtained fatty acid isobutyl esters(FABEs)was conducted in the presence of formic acid and hydrogen peroxide.The Ep-FABEs was further analyzed for its plasticizing effectiveness to replace dioctyl phthalate(DOP)and compared with conventional epoxy plasticizer epoxidized fatty acid methyl esters(Ep-FAMEs).The results indicated that the thermal stability and mechanical properties of PVC films with Ep-FABEs plasticizer were significantly improved compared with those plasticized with DOP.In addition,the extraction resistance and migration stability of Ep-FABEs were better than those of EpFAMEs.Overall,the prepared Ep-FABEs via structural modification of biodiesel proved to be a promising biobased plasticizer.展开更多
To study the characteristic of liquid-liquid extraction equilibrium of lithium from brine sources, the complexes formed from tributyl phosphate （TBP） and methyl isobutyl ketone （MIBK） with lithium were investi- ga...To study the characteristic of liquid-liquid extraction equilibrium of lithium from brine sources, the complexes formed from tributyl phosphate （TBP） and methyl isobutyl ketone （MIBK） with lithium were investi- gated using FeCl3 as coextracting agent. Liquid-liquid extraction reaction mechanisms were proposed and the stoichiometry of tetrachloroferrate（III） complex with lithium was obtained by regressing the experimental data. It is found that the stoichiometry of tetrachloroferrate（III） to lithium in the complex is 1 ： 1 with either TBP or MIBK as extractant in kerosene. The stoichiometry of the complex of TBP with Li was 1 ： 1 and that of MIBK with Li was 2 ： 1. The formed complexes of TBP and MIBK with lithium are determined to be LiFeCla-TBP and LiFeC14.2MIBK, respectively, according to the rule of neutralization.展开更多
Effectiveness of pulsed power plasma for the degradation of two toxic volatile organic compounds(VOCs),toluene and methyl isobutyl ketone(MIBK),in aqueous solution was evaluated.The plasma degradation of MIBK has been...Effectiveness of pulsed power plasma for the degradation of two toxic volatile organic compounds(VOCs),toluene and methyl isobutyl ketone(MIBK),in aqueous solution was evaluated.The plasma degradation of MIBK has been studied for the first time.The influence of initial concentration of target compound,solution pH and scavengers on percentage degradation was evaluated.100%removal of 200 mg/L of toluene and MIBK was achieved both in liquid and gaseous phases after 12 and 16 min of plasma treatment,respectively.The first order rate constant of toluene and MIBK degradation(for 200 mg/L each)was 0.421 and 0.319 min~(-1)respectively when they were treated individually,and these values decreased slightly during degradation of their mixture.MIBK degradation was slower than toluene and it might be due to semi volatile and hydrophilic nature of MIBK.The effect of initial concentration of toluene and MIBK showed different degradation patterns.Highest degradation of both the compounds was obtained in neutral pH and in absence of scavengers.·OH radical was the major reactive species involved in their degradation.Their degradation in real environmental matrices showed that removal reduced significantly in secondary effluent due to scavenging of reactive species by various ions and organic matter.The total number of degradation intermediates identified in case of toluene and MIBK was 11 and 14 respectively and formate was the one recalcitrant byproduct generated.The degradation pathway of toluene and MIBK involving reactions of reactive oxygen and nitrogen species and reductive species is proposed.展开更多
A sensitive solvent extraction method for the determination of nonamolar concentrations of silicate in natural waters is developed. According to the traditional aqueous silicate method, silicomolybdenum blue formed by...A sensitive solvent extraction method for the determination of nonamolar concentrations of silicate in natural waters is developed. According to the traditional aqueous silicate method, silicomolybdenum blue formed by the reaction between silicate and ammoni- um molydate and reduced by metol-sulfite reagent is extracted by methyl isobutyl ketone. The absorbance can be enhanced substantially up to 10-folds. The detection limit of silicate is 8 nmol/dm^3 , which is one tenth smaller than the traditional method, with the precision of 4.0% at a silicate level of 50 nmol/dm^3 and 3.2% at a silicate level of 6 μmol/dm^3. Comparing the calibration curves in the distilled water and seawater, it can be seen that the salt effect also exists in the extraction method. However, the salt effect is a linear function of the salinity and can be corrected by simple calibration. The proposed method is successfully applied to the determination of silicate in natural waters. Natural concentrations of arsenate, arsenite and phosphate cause negligible interference.展开更多
The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom tw...The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom two-liquid(NRTL) model was used to correlate the experimental data and to yield corresponding binary interaction parameters for these salt containing systems.The Hand and Othmer–Tobias equations were used to confirm the dependability of the determined LLE data in this work.Distribution coefficient and selectivity were used to evaluate the extraction performance of methyl isobutyl ketone with the existence of salt.The magnitude of salt effect on the water + phenol + methyl isobutyl ketone(MIBK) system is in the following order: Na_2SO_4>NaCl>KCl.展开更多
Phthalates are a large family of ubiquitous environmental pollutants suspected of being endocrine disruptors. Epidemiological studies have associated phthalate metabolites with decreased reproductive parameters and li...Phthalates are a large family of ubiquitous environmental pollutants suspected of being endocrine disruptors. Epidemiological studies have associated phthalate metabolites with decreased reproductive parameters and linked phthalate exposure with the level of urinary 5-methyl-2′-deoxycytidine（5mdC, a product of methylated DNA）. In this study, adult male mice were exposed to 450 mg di-isobutyl phthalate（DiBP）/（kg·day） via dietary exposure for 28 days. Mono-isobutyl phthalate（Mi BP, the urinary metabolite） and reproductive function parameters were determined. The levels of 5mdC and 5-hydroxymethyl-2′-deoxycytidine（5hmdC） were measured in urine to evaluate if their contents were also altered by DiBP exposure in this animal model. Results showed that DiBP exposure led to a significant increase in the urinary 5mdC level and significant decreases in sperm concentration and motility in the epididymis, accompanied with reduced testosterone levels and downregulation of the P450 cholesterol side-chain cleavage enzyme（P450scc） gene in the mice testes. Our findings indicated that exposure to DiBP increased the urinary 5mdC levels,which supported our recent epidemiological study about the associations of urinary 5mdC with phthalate exposure in the male human population. In addition, DiBP exposure impaired male reproductive function, possibly by disturbing testosterone levels; P450scc might be a major steroidogenic enzyme targeted by DiBP or other phthalates.展开更多
Effect of isobutyl-triethoxy-silane penetrative protective agent on the carbonation resistance of the concrete was studied.The concrete specimens for the 28 d accelerated carbonation process were manufactured with w/c...Effect of isobutyl-triethoxy-silane penetrative protective agent on the carbonation resistance of the concrete was studied.The concrete specimens for the 28 d accelerated carbonation process were manufactured with w/c of 0.49 and 0.64,both in the presence and absence of silane and mineral admixture.The penetration of isobutyl-triethoxy-silane and the carbonation of concrete were investigated by penetration depth,carbonation depth,XRD,SEM,and pore size distribution.The results showed that concrete compactness played an important role in the silane penetration and carbonation resistance.Penetration depth of silane-treated concrete mainly depended on the compactness of the concrete,and could not remarkably change through the accelerated carbonation process.In the accelerated carbonation process,penetrative protective agent improved the carbonation resistance of the higher compactness concretes but accelerated the carbonization process of the lower compactness concretes.As penetrative protective agent penetrated along the external connectivity pores into concrete not filling the entire surface area,the inorganic film could not fully protect the Ca（OH）_2 phase from carbonation.After 28 d accelerated carbonation,fibrous hydration products disappeared and the surface holes decreased.Due to the formation of carbonized products,the porosity of the concrete surface decreased,especially in high-strength concrete.展开更多
Polymerization of isobutyl vinyl ether(IBVE)has been studied with mononuclear half-titanocene,CpTiCl_3[1]and dinuclear half-titanocenes,[(C_5H_4)_2(CH_2)_n][(TiCl_3)_2][2(n=3),3(n=6)],and[(C_5H_4)_2(CH_2)_n[(TiCl_2OR_...Polymerization of isobutyl vinyl ether(IBVE)has been studied with mononuclear half-titanocene,CpTiCl_3[1]and dinuclear half-titanocenes,[(C_5H_4)_2(CH_2)_n][(TiCl_3)_2][2(n=3),3(n=6)],and[(C_5H_4)_2(CH_2)_n[(TiCl_2OR_2](R=2,6- diisopropylphenoxyl)[4(n=3),5(n=6)],in the presence of methyl aluminoxanes(MAO)as cocatalyst in methylene chloride.The influences of the length of polymethylene brigde and the substitution of aryloxy group at the metal center have been investigated at three polymerization temperature(...展开更多
Supported nickel-based catalysts were prepared by the incipient wetness impregnation method for the selective hydrogenation of methyl isobutyl ketone to methyl isobutyl carbinol in a fixed-bed reactor. The effects of ...Supported nickel-based catalysts were prepared by the incipient wetness impregnation method for the selective hydrogenation of methyl isobutyl ketone to methyl isobutyl carbinol in a fixed-bed reactor. The effects of the nickel source,Ni loading, calcination time, and calcination temperature on the hydrogenation performance were studied. The experimental results showed that the Ni/γ-Al_2O_3 catalyst demonstrated the highest catalytic performance under the preparation conditions by using nickel nitrate as the nickel source with a NiO loading of 20%, followed by calcination at 440°C for 5h. In addition,this catalyst showed the largest specific surface area, best crystal structure, highest active component content, smallest particle size, and uniform distribution of NiO on the surface of the carrier. The nickel-based catalyst prepared using the optimized conditions exhibited a 96.1% conversion of methyl isobutyl ketone, with a methyl isobutyl carbinol selectivity of 99.6%. The described procedure is very effective for the preparation of methyl isobutyl carbinol using methyl isobutyl ketone as the feedstock.展开更多
A few factors affecting plasma oxidation desulfurization of isobutyl mercaptan were investigated. Under the reasonable condition, the conversion and degree of desulfurization of isobutyl mercaptan can be achieved up t...A few factors affecting plasma oxidation desulfurization of isobutyl mercaptan were investigated. Under the reasonable condition, the conversion and degree of desulfurization of isobutyl mercaptan can be achieved up to over 95% and 94％ respectively.展开更多
2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide（H-2-65） was synthesized by the reaction of Harmine with 1-iodobutane via N9-alkylation, demethyl and N2-quaternarization to obtain the new compound. The re...2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide（H-2-65） was synthesized by the reaction of Harmine with 1-iodobutane via N9-alkylation, demethyl and N2-quaternarization to obtain the new compound. The results demonstrate that H-2-65 has more remarkable anticancer activities in vitro. The results of 1H NMR, 13 C NMR, DEPT, g COSY, g HSQC, g HMBC, MS, single-crystal X-ray diffraction and elemental analysis showed that the title compound crystallizes in the triclinic system, space group P1 with a = 9.545（5）, b = 11.724（5）, c = 11.839（6） , α = 77.530（6）, β = 87.169（6）, γ = 72.823（5）o, Z = 2, V = 1235.8（10）3, Dc = 1.294 g·cm-3, F（000） = 504, the final R = 0.0453, wR = 0.1262 and S = 1.044.展开更多
In this experiment, allyl isothiocyanate and isobutanol were used as raw materials, and allyl isobutyl thiocarbamate was synthesized by one-step polymerization at a certain temperature under the action of catalyst. In...In this experiment, allyl isothiocyanate and isobutanol were used as raw materials, and allyl isobutyl thiocarbamate was synthesized by one-step polymerization at a certain temperature under the action of catalyst. In this paper, the experiments were carried out from the following four factors: the ratio of raw materials, the amount of catalyst, the reaction time and the protection of the reaction system, and the optimum synthesis conditions were determined. The yield of allyl isothiocyanate and isobutanol is greatly improved after the synthesis process is optimized by adding 100ml/100ml of allyl isothiocyanate and isobutanol, adding 0.8g of catalyst and keeping the temperature at 110℃ for 5 hours. The raw materials are recycled through vacuum distillation, and the purity of the purified product reaches high quality and the impurity content of the product is reduced. In short, the products synthesized by this process are all qualified products, and the content is much higher than other products in the same industry. The product has high yield and low price, has great market advantages, and is an economical and environment-friendly synthesis process.展开更多
Extraction behavior of lanthanides(La, Eu, Dy, Lu) from HNO3 solution was studied using a novel extraction system with hydrophobic ionic liquid being diluent and isobutyl-BTP being extractant. Compared with that in is...Extraction behavior of lanthanides(La, Eu, Dy, Lu) from HNO3 solution was studied using a novel extraction system with hydrophobic ionic liquid being diluent and isobutyl-BTP being extractant. Compared with that in isobutyl-BTP/cyclohexane extraction system, application of ionic liquid as the extracting phase provided unprecedented enhancement of the extraction performance of isobutyl-BTP for lanthanides. It was found that the isobutyl-BTP/[Cnmim][NTf2] extraction system is favorable to get good extraction at low acidity condition(< 0.1 M). Of all the isobutyl-BTP/ [C n mim][NTf2](n = 2, 6, 8) systems, isobutyl-BTP/[C2mim][NTf2]extraction system provides the best extraction performance and fastest extraction kinetics within 5 min towards Dy3+. The extraction is spontaneous endothermic and temperature is good for extraction. The transfer of lanthanides, in isobutyl-BTP/[C2mim][NTf2] extraction system, proceeded via a cation exchange mechanism, in contrast to extraction of neutral complex in the cyclohexane system.展开更多
目的 建立电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)测定注射用亚锡甲氧异腈中元素杂质的含量。方法 样品溶解后,采用ICP-MS半定量测定模式对注射用亚锡甲氧异腈中元素杂质进行初步筛查,结合国际...目的 建立电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)测定注射用亚锡甲氧异腈中元素杂质的含量。方法 样品溶解后,采用ICP-MS半定量测定模式对注射用亚锡甲氧异腈中元素杂质进行初步筛查,结合国际人用药品注册技术协调会(International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use,ICH)Q3D元素杂质指导原则的要求,确定16种元素:锂(Li)、镁(Mg)、铝(Al)、硅(Si)、钾(K)、钒(V)、铁(Fe)、钴(Co)、镍(Ni)、锌(Zn)、砷(As)、镉(Cd)、铟(In)、锑(Sb)、汞(Hg)和铅(Pb)作为定量考察和控制的元素杂质研究对象。ICP-MS采集模式选择动能歧视模式进行定量方法研究,分别以钪(Sc)、锗(Ge)、钇(Y)、铋(Bi)作为内标,测定16种元素杂质的含量。结果 16种元素杂质在各自线性范围内响应与浓度相关性良好(r≥0.999 3);方法精密度(RSD≤3.53%)和重复性(RSD≤3.69%)均较好;各元素平均回收率为95.86%~105.64%(RSD≤5.06%,n=9),方法准确性良好。注射用亚锡甲氧异腈样品中16种元素均未超出限度,Mg、K、Zn 3种元素含量相对较高。结论 金属盐类制剂产品可能引入ICH Q3D原则要求以外的元素杂质。本研究建立的ICP-MS定量方法简便、快速,可用于注射用亚锡甲氧异腈中元素杂质的筛查、检测和风险评估。展开更多
基金Financial support provided by the National High-tech Research and Development Program of China(2014AA022103)。
文摘Biodiesel was used to prepare epoxidized fatty acid isobutyl esters(Ep-FABEs)as a biobased plasticizer in this work.Transesterification of biodiesel with isobutanol catalyzed by tetrabutyl titanate was carried out in a gas-liquid tower reactor.The conversion achieved nearly 100%within 5 h under the reaction temperature,the mass ratio of catalyst to fatty acid methyl esters(FAMEs),and isobutanol to FAMEs total molar ratio of 180℃,0.4%(mass),and 5.4:1,respectively.In addition,kinetic model of the transesterification reaction was developed at 150–190℃.The calculated activation energy was 48.93 kJ·mol^(-1).Then,the epoxidation of obtained fatty acid isobutyl esters(FABEs)was conducted in the presence of formic acid and hydrogen peroxide.The Ep-FABEs was further analyzed for its plasticizing effectiveness to replace dioctyl phthalate(DOP)and compared with conventional epoxy plasticizer epoxidized fatty acid methyl esters(Ep-FAMEs).The results indicated that the thermal stability and mechanical properties of PVC films with Ep-FABEs plasticizer were significantly improved compared with those plasticized with DOP.In addition,the extraction resistance and migration stability of Ep-FABEs were better than those of EpFAMEs.Overall,the prepared Ep-FABEs via structural modification of biodiesel proved to be a promising biobased plasticizer.
基金Supported by the National High Technology Research and Development Program of China (2008AA06Z111)the Qinghai Key Technology R&D Program (2011-J-154)
文摘To study the characteristic of liquid-liquid extraction equilibrium of lithium from brine sources, the complexes formed from tributyl phosphate （TBP） and methyl isobutyl ketone （MIBK） with lithium were investi- gated using FeCl3 as coextracting agent. Liquid-liquid extraction reaction mechanisms were proposed and the stoichiometry of tetrachloroferrate（III） complex with lithium was obtained by regressing the experimental data. It is found that the stoichiometry of tetrachloroferrate（III） to lithium in the complex is 1 ： 1 with either TBP or MIBK as extractant in kerosene. The stoichiometry of the complex of TBP with Li was 1 ： 1 and that of MIBK with Li was 2 ： 1. The formed complexes of TBP and MIBK with lithium are determined to be LiFeCla-TBP and LiFeC14.2MIBK, respectively, according to the rule of neutralization.
基金the financial support received from Department of Science and Technology(DST),Government of India(Nos.DST/TM/WTI/WIC/2K17/82(G)and DST/CCP/Co E/141/2018(G))for this study。
文摘Effectiveness of pulsed power plasma for the degradation of two toxic volatile organic compounds(VOCs),toluene and methyl isobutyl ketone(MIBK),in aqueous solution was evaluated.The plasma degradation of MIBK has been studied for the first time.The influence of initial concentration of target compound,solution pH and scavengers on percentage degradation was evaluated.100%removal of 200 mg/L of toluene and MIBK was achieved both in liquid and gaseous phases after 12 and 16 min of plasma treatment,respectively.The first order rate constant of toluene and MIBK degradation(for 200 mg/L each)was 0.421 and 0.319 min~(-1)respectively when they were treated individually,and these values decreased slightly during degradation of their mixture.MIBK degradation was slower than toluene and it might be due to semi volatile and hydrophilic nature of MIBK.The effect of initial concentration of toluene and MIBK showed different degradation patterns.Highest degradation of both the compounds was obtained in neutral pH and in absence of scavengers.·OH radical was the major reactive species involved in their degradation.Their degradation in real environmental matrices showed that removal reduced significantly in secondary effluent due to scavenging of reactive species by various ions and organic matter.The total number of degradation intermediates identified in case of toluene and MIBK was 11 and 14 respectively and formate was the one recalcitrant byproduct generated.The degradation pathway of toluene and MIBK involving reactions of reactive oxygen and nitrogen species and reductive species is proposed.
基金The National Science Foundation of China under contract No.40606028the Special Fund from the National Key Basic Research Program of China under contract No.2006CB400601.
文摘A sensitive solvent extraction method for the determination of nonamolar concentrations of silicate in natural waters is developed. According to the traditional aqueous silicate method, silicomolybdenum blue formed by the reaction between silicate and ammoni- um molydate and reduced by metol-sulfite reagent is extracted by methyl isobutyl ketone. The absorbance can be enhanced substantially up to 10-folds. The detection limit of silicate is 8 nmol/dm^3 , which is one tenth smaller than the traditional method, with the precision of 4.0% at a silicate level of 50 nmol/dm^3 and 3.2% at a silicate level of 6 μmol/dm^3. Comparing the calibration curves in the distilled water and seawater, it can be seen that the salt effect also exists in the extraction method. However, the salt effect is a linear function of the salinity and can be corrected by simple calibration. The proposed method is successfully applied to the determination of silicate in natural waters. Natural concentrations of arsenate, arsenite and phosphate cause negligible interference.
基金Supported by the National Natural Science Foundation of China(21506066)State Key Laboratory of Pulp and Paper Engineering(201708)+2 种基金the Guangdong Natural Science Foundation(2014A030310260)the Fundamental Research Funds for the Central Universities SCUT(2017ZD069)the Guangzhou Technology Project(201804010219)
文摘The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom two-liquid(NRTL) model was used to correlate the experimental data and to yield corresponding binary interaction parameters for these salt containing systems.The Hand and Othmer–Tobias equations were used to confirm the dependability of the determined LLE data in this work.Distribution coefficient and selectivity were used to evaluate the extraction performance of methyl isobutyl ketone with the existence of salt.The magnitude of salt effect on the water + phenol + methyl isobutyl ketone(MIBK) system is in the following order: Na_2SO_4>NaCl>KCl.
基金supported by the National Basic Research Program of China (973No.2013CB945004)the National Natural Science Foundation of China (No.21477127)
文摘Phthalates are a large family of ubiquitous environmental pollutants suspected of being endocrine disruptors. Epidemiological studies have associated phthalate metabolites with decreased reproductive parameters and linked phthalate exposure with the level of urinary 5-methyl-2′-deoxycytidine（5mdC, a product of methylated DNA）. In this study, adult male mice were exposed to 450 mg di-isobutyl phthalate（DiBP）/（kg·day） via dietary exposure for 28 days. Mono-isobutyl phthalate（Mi BP, the urinary metabolite） and reproductive function parameters were determined. The levels of 5mdC and 5-hydroxymethyl-2′-deoxycytidine（5hmdC） were measured in urine to evaluate if their contents were also altered by DiBP exposure in this animal model. Results showed that DiBP exposure led to a significant increase in the urinary 5mdC level and significant decreases in sperm concentration and motility in the epididymis, accompanied with reduced testosterone levels and downregulation of the P450 cholesterol side-chain cleavage enzyme（P450scc） gene in the mice testes. Our findings indicated that exposure to DiBP increased the urinary 5mdC levels,which supported our recent epidemiological study about the associations of urinary 5mdC with phthalate exposure in the male human population. In addition, DiBP exposure impaired male reproductive function, possibly by disturbing testosterone levels; P450scc might be a major steroidogenic enzyme targeted by DiBP or other phthalates.
基金Funded by the National Sci-Tech Support Plan of China(No.2013BAJ10B05)Marine Interdisciplinary Research Guide Fund of Zhejiang University(No.2012HY003B)
文摘Effect of isobutyl-triethoxy-silane penetrative protective agent on the carbonation resistance of the concrete was studied.The concrete specimens for the 28 d accelerated carbonation process were manufactured with w/c of 0.49 and 0.64,both in the presence and absence of silane and mineral admixture.The penetration of isobutyl-triethoxy-silane and the carbonation of concrete were investigated by penetration depth,carbonation depth,XRD,SEM,and pore size distribution.The results showed that concrete compactness played an important role in the silane penetration and carbonation resistance.Penetration depth of silane-treated concrete mainly depended on the compactness of the concrete,and could not remarkably change through the accelerated carbonation process.In the accelerated carbonation process,penetrative protective agent improved the carbonation resistance of the higher compactness concretes but accelerated the carbonization process of the lower compactness concretes.As penetrative protective agent penetrated along the external connectivity pores into concrete not filling the entire surface area,the inorganic film could not fully protect the Ca（OH）_2 phase from carbonation.After 28 d accelerated carbonation,fibrous hydration products disappeared and the surface holes decreased.Due to the formation of carbonized products,the porosity of the concrete surface decreased,especially in high-strength concrete.
基金the Korea Ministry of Commerce,Industry,and Energy(Grant RTI04-01-04,Regional Technology Innovation Program).
文摘Polymerization of isobutyl vinyl ether(IBVE)has been studied with mononuclear half-titanocene,CpTiCl_3[1]and dinuclear half-titanocenes,[(C_5H_4)_2(CH_2)_n][(TiCl_3)_2][2(n=3),3(n=6)],and[(C_5H_4)_2(CH_2)_n[(TiCl_2OR_2](R=2,6- diisopropylphenoxyl)[4(n=3),5(n=6)],in the presence of methyl aluminoxanes(MAO)as cocatalyst in methylene chloride.The influences of the length of polymethylene brigde and the substitution of aryloxy group at the metal center have been investigated at three polymerization temperature(...
基金financially supported by the National Natural Science Foundation of China (91634101)the Project on Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality (IDHT20180508)
文摘Supported nickel-based catalysts were prepared by the incipient wetness impregnation method for the selective hydrogenation of methyl isobutyl ketone to methyl isobutyl carbinol in a fixed-bed reactor. The effects of the nickel source,Ni loading, calcination time, and calcination temperature on the hydrogenation performance were studied. The experimental results showed that the Ni/γ-Al_2O_3 catalyst demonstrated the highest catalytic performance under the preparation conditions by using nickel nitrate as the nickel source with a NiO loading of 20%, followed by calcination at 440°C for 5h. In addition,this catalyst showed the largest specific surface area, best crystal structure, highest active component content, smallest particle size, and uniform distribution of NiO on the surface of the carrier. The nickel-based catalyst prepared using the optimized conditions exhibited a 96.1% conversion of methyl isobutyl ketone, with a methyl isobutyl carbinol selectivity of 99.6%. The described procedure is very effective for the preparation of methyl isobutyl carbinol using methyl isobutyl ketone as the feedstock.
基金The project was supported by National Natural Science Foundation of China.
文摘A few factors affecting plasma oxidation desulfurization of isobutyl mercaptan were investigated. Under the reasonable condition, the conversion and degree of desulfurization of isobutyl mercaptan can be achieved up to over 95% and 94％ respectively.
基金Supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2012BAI30B00)
文摘2-Benzyl-7-butoxyl-9-isobutyl-1-methyl-β-carboline bromide（H-2-65） was synthesized by the reaction of Harmine with 1-iodobutane via N9-alkylation, demethyl and N2-quaternarization to obtain the new compound. The results demonstrate that H-2-65 has more remarkable anticancer activities in vitro. The results of 1H NMR, 13 C NMR, DEPT, g COSY, g HSQC, g HMBC, MS, single-crystal X-ray diffraction and elemental analysis showed that the title compound crystallizes in the triclinic system, space group P1 with a = 9.545（5）, b = 11.724（5）, c = 11.839（6） , α = 77.530（6）, β = 87.169（6）, γ = 72.823（5）o, Z = 2, V = 1235.8（10）3, Dc = 1.294 g·cm-3, F（000） = 504, the final R = 0.0453, wR = 0.1262 and S = 1.044.
文摘In this experiment, allyl isothiocyanate and isobutanol were used as raw materials, and allyl isobutyl thiocarbamate was synthesized by one-step polymerization at a certain temperature under the action of catalyst. In this paper, the experiments were carried out from the following four factors: the ratio of raw materials, the amount of catalyst, the reaction time and the protection of the reaction system, and the optimum synthesis conditions were determined. The yield of allyl isothiocyanate and isobutanol is greatly improved after the synthesis process is optimized by adding 100ml/100ml of allyl isothiocyanate and isobutanol, adding 0.8g of catalyst and keeping the temperature at 110℃ for 5 hours. The raw materials are recycled through vacuum distillation, and the purity of the purified product reaches high quality and the impurity content of the product is reduced. In short, the products synthesized by this process are all qualified products, and the content is much higher than other products in the same industry. The product has high yield and low price, has great market advantages, and is an economical and environment-friendly synthesis process.
基金Supported by the National Natural Science Foundation of China(Nos.91126006 and 11475112)the Ph.D.Programs Foundation of Ministry of Education of China(No.20130073120051)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning
文摘Extraction behavior of lanthanides(La, Eu, Dy, Lu) from HNO3 solution was studied using a novel extraction system with hydrophobic ionic liquid being diluent and isobutyl-BTP being extractant. Compared with that in isobutyl-BTP/cyclohexane extraction system, application of ionic liquid as the extracting phase provided unprecedented enhancement of the extraction performance of isobutyl-BTP for lanthanides. It was found that the isobutyl-BTP/[Cnmim][NTf2] extraction system is favorable to get good extraction at low acidity condition(< 0.1 M). Of all the isobutyl-BTP/ [C n mim][NTf2](n = 2, 6, 8) systems, isobutyl-BTP/[C2mim][NTf2]extraction system provides the best extraction performance and fastest extraction kinetics within 5 min towards Dy3+. The extraction is spontaneous endothermic and temperature is good for extraction. The transfer of lanthanides, in isobutyl-BTP/[C2mim][NTf2] extraction system, proceeded via a cation exchange mechanism, in contrast to extraction of neutral complex in the cyclohexane system.
文摘目的 建立电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)测定注射用亚锡甲氧异腈中元素杂质的含量。方法 样品溶解后,采用ICP-MS半定量测定模式对注射用亚锡甲氧异腈中元素杂质进行初步筛查,结合国际人用药品注册技术协调会(International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use,ICH)Q3D元素杂质指导原则的要求,确定16种元素:锂(Li)、镁(Mg)、铝(Al)、硅(Si)、钾(K)、钒(V)、铁(Fe)、钴(Co)、镍(Ni)、锌(Zn)、砷(As)、镉(Cd)、铟(In)、锑(Sb)、汞(Hg)和铅(Pb)作为定量考察和控制的元素杂质研究对象。ICP-MS采集模式选择动能歧视模式进行定量方法研究,分别以钪(Sc)、锗(Ge)、钇(Y)、铋(Bi)作为内标,测定16种元素杂质的含量。结果 16种元素杂质在各自线性范围内响应与浓度相关性良好(r≥0.999 3);方法精密度(RSD≤3.53%)和重复性(RSD≤3.69%)均较好;各元素平均回收率为95.86%~105.64%(RSD≤5.06%,n=9),方法准确性良好。注射用亚锡甲氧异腈样品中16种元素均未超出限度,Mg、K、Zn 3种元素含量相对较高。结论 金属盐类制剂产品可能引入ICH Q3D原则要求以外的元素杂质。本研究建立的ICP-MS定量方法简便、快速,可用于注射用亚锡甲氧异腈中元素杂质的筛查、检测和风险评估。
