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溶度参数法提取补阳还五汤不同极性段成分群的研究 被引量:2
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作者 段晓鹏 贺福元 《中南药学》 CAS 2015年第4期358-361,共4页
目的采用溶度参数法分离提取补阳还五汤浸膏中不同极性段成分群,为建立适应中药复方特点的有效性研究方法提供新的思维方法和实验依据。方法选择正已烷、正已烷-正丁醇(1:1)、正丁醇、乙醇、甲醇、83%甲醇、68%甲醇、51%甲醇、34%甲醇、... 目的采用溶度参数法分离提取补阳还五汤浸膏中不同极性段成分群,为建立适应中药复方特点的有效性研究方法提供新的思维方法和实验依据。方法选择正已烷、正已烷-正丁醇(1:1)、正丁醇、乙醇、甲醇、83%甲醇、68%甲醇、51%甲醇、34%甲醇、18%甲醇以及水11种不同溶度参数的溶剂获取补阳还五汤浸膏不同极性段有效成分群,并用反相HPLC考察各成分群指纹图谱特征及相似度评价。结果 11种不同溶度参数的溶剂可以分别提取分离得到补阳还五汤不同极性段成分群,且不同处理样品液指纹图谱相似度差异大,所含成分类别与含量也不同。结论溶度参数法能够应用于中药复方多成分的提取分离,为中药复方有效性研究提供了新的思路和实验基础。 展开更多
关键词 补阳还五汤 溶度参数 中药有效性 指纹图谱 极性段成分群
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相溶度分析法测定布洛芬对照品的含量
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作者 赵慧玲 杨腊虎 俞如英 《化学世界》 CAS CSCD 1996年第S1期255-255,共1页
相溶度分析法测定布洛芬对照品的含量赵慧玲,杨腊虎,俞如英(中国药品生物制品检定所北京100050)布咯芬为非甾体消炎镇痛药。目前,临床上广泛应用于类风风湿性关节炎,风湿性关节炎,强直性脊柱炎等。美国药典第23版、英国... 相溶度分析法测定布洛芬对照品的含量赵慧玲,杨腊虎,俞如英(中国药品生物制品检定所北京100050)布咯芬为非甾体消炎镇痛药。目前,临床上广泛应用于类风风湿性关节炎,风湿性关节炎,强直性脊柱炎等。美国药典第23版、英国药典(93版)、日本药局方第12改... 展开更多
关键词 溶度分析 布洛芬 对照品 风湿性关节炎 日本药局方 世界卫生组织 美国药典 药物分析 英国药典 中国药典
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Framework-solvent interactional mechanism and effect of NMP/DMF on solvothermal synthesis of [Zn_4O(BDC)_3]_8 被引量:3
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作者 吴争平 王明雪 +4 位作者 周丽姣 尹周澜 谈进 张锦玲 陈启元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3722-3731,共10页
In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) o... In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF. 展开更多
关键词 solvothermal synthesis [Zn4O(BDC)3]8 N-METHYL-2-PYRROLIDONE interactional mechanism COSMO solvation model density functional method
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化学系
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《山东海洋学院学报》 1985年第C00期81-90,共10页
用溶度法研究在不同pH值下的亚铊和硫氰酸根的络合反应,极谱法研究亚铊离子与硫代硫酸根的络合反应,用分光光度法求混合配位体络合物的各级稳定常数和克分子消光系数的一种一般处理方法,电负性应用的新进展,溶液中络合物逐级稳定常... 用溶度法研究在不同pH值下的亚铊和硫氰酸根的络合反应,极谱法研究亚铊离子与硫代硫酸根的络合反应,用分光光度法求混合配位体络合物的各级稳定常数和克分子消光系数的一种一般处理方法,电负性应用的新进展,溶液中络合物逐级稳定常数与配位数之间的S型关系和直线关系,海水中无机离子交换分级平衡理论研究…… 展开更多
关键词 溶度法 pH值 亚铊 硫氰酸根 络合反应 极谱 海洋化学
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抗肿瘤药物依托泊甙的质量研究 被引量:2
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作者 罗远秀 杨腊虎 《药物分析杂志》 CAS CSCD 北大核心 1994年第5期25-27,共3页
本文采用溶剂重结晶法精制抗肿瘤药物依托泊甙(etoposide),精制前后用UV、IR及TLC进行检查;用相溶度分析法和高效液相色谱法测定含量;用热分析方法测定了依托泊甙的热特征。精制后的依托泊甙纯度达99%以上。
关键词 依托泊甙 溶度分析 热分析
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Measurement and Correlation of the Solubility of Ligusticum Chuanxiong oil in Supercritical CO_2 被引量:7
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作者 孙永跃 李淑芬 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期796-799,共4页
Extraction of the Ligusticum Chuanxiong oil with supercritical CO2 (SC-CO2) was investigated at the temperatures ranging from 55℃ to 70℃ and pressure from 25 MPa to 35 MPa. The mass of Ligusticum Chuanxiong oil ex... Extraction of the Ligusticum Chuanxiong oil with supercritical CO2 (SC-CO2) was investigated at the temperatures ranging from 55℃ to 70℃ and pressure from 25 MPa to 35 MPa. The mass of Ligusticum Chuanxiong oil extracted increased with pressure at constant temperature. The initial slope of the extraction was considered as the solubility of oil in SC-CO2. Chrastil equation was used to correlate the solubility data of Ligusticum Chuanxiong oil. An improved Chrastil equation was also presented and was employed to correlate the solubility data, The correlation results show that the values of the average absolute relative deviation are 5.94% and 3.33% respectively, indicating the improved version has better correlation accuracy than that of Chrastil equation. 展开更多
关键词 supercritical CO2 extraction SOLUBILITY Ligusticum Chuanxiong oil CORRELATION
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Measurement and Correlation of Solubility of Carbon Monoxide in Phenol+Ethanol Solvents 被引量:1
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作者 宣爱国 吴元欣 +2 位作者 马沛生 孙炜 沈喜珊 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第5期762-765,共4页
The solubility of carbon monoxide in phenol+ethanol mixed solvents at elevated pressures is reported in this article. The experimental results revealed the influence of pressure on the solubility of CO in phenol+eth... The solubility of carbon monoxide in phenol+ethanol mixed solvents at elevated pressures is reported in this article. The experimental results revealed the influence of pressure on the solubility of CO in phenol+ethanol mixtures. These mixtures are a poorer solvent for carbon monoxide. The solubility of CO is a linear function of pressure, and the extended Henry's constants were presented at different concentrations of phenol. The cubic Soave-Redlich-Kwong equation of state was used to correlate the experimental gas liquid equilibrium data and to predict the solubility of CO. At the same time, the binary interaction parameters, kO, for CO-phenol, CO-ethanol and phenol-ethanol systems were estimated by fitting experimental GLE data at 303.15 K and at 2.0-9.0 MPa. Hence, a model was suggested for the solubility of CO in phenol+ethanol mixed solvents. The agreement between experimental and calculated solubilities with the proposed model was rather satisfactory. 展开更多
关键词 solubility gas-liquid equilibnum carbon monoxide phenol ethanol
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CHARACTERISTICS AND FORMATION CAUSES OF QINGDAO COLD WATER MASS 被引量:10
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作者 张启龙 刘兴泉 +1 位作者 程明华 于新胜 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第4期303-308,共6页
In this work, the main characteristics of the Qingdao Cold Water Mass were studied by using "the comparison analysis method" based on 1980 temperature,salinity and dissolved oxygen data on the western South ... In this work, the main characteristics of the Qingdao Cold Water Mass were studied by using "the comparison analysis method" based on 1980 temperature,salinity and dissolved oxygen data on the western South Yellow Sea. The formation cause of the water mass was analyzed based on February of 1959 temperature and salinity data for this area and on some other authors’ studies. The results showed that the Qingdao Cold Water Mass has growing and vanishing processes: appears in the last ten days of March; has stable pattern in April; is biggest in its area in May; becomes small in its area in June; vanishes in July. It comes from the northern Shandong Coastal Water and is characterized by low temperature and salinity and high dissolved oxygen. The mass is formed under the joint effects of anticyclonic circulation and solar radiation. 展开更多
关键词 Qingdao Cold Water Mass characteristics formation cause
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The Determination of Average Stability Constant of NickeI-FA Complex at pH = 8,0 by the Solubility Method
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作者 Giorgi Makharadze Nazi Goliadze +1 位作者 Tamar Makharadze Guram Supatashvili 《Journal of Chemistry and Chemical Engineering》 2014年第4期344-348,共5页
At pH = 8, the complex formation process of Ni(Ⅱ) ions with FA was studied by the solubility method. FA were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) w... At pH = 8, the complex formation process of Ni(Ⅱ) ions with FA was studied by the solubility method. FA were separated from the river Mtkvari by the adsorption-chromotographic method. The charcoal (BAU, Russia) was used as a sorbent. The old suspension of Ni(Ⅱ) hydroxide was used as the solid phase, on which was added the increasing quantity of standard solution of FA. In diluted solutions, at pH = 8.0 the dominant form of Ni(Ⅱ) is nickel dihydroxocomplex Ni(OH)2^0. It was established that in the Ni(OH)2(solid)-Ni(OH)2^0(solution)-FA2-H20 system dominates nickel dyhydroxofulvate complex with the structure 1:1, [Ni(OH)2FA]2-. The average stability constant of nickel dyhydroxofulvate complex was calculated based on experimental data flNi(OH)2FA2" = 5.3 × 105. 展开更多
关键词 NICKEL FA average stability constant nickel fulvate water.
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Effects of electrolysis process parameters on alumina dissolution and their optimization 被引量:9
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作者 Wen-yuan HOU He-song LI +2 位作者 Mao LI Ben-jun CHENG Yuan FENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第12期3390-3403,共14页
The Box–Behnken design and desirability approach were used to investigate and optimize the process parameters for aluminum reduction cells related to alumina dissolution. The bath temperature, alumina content, curren... The Box–Behnken design and desirability approach were used to investigate and optimize the process parameters for aluminum reduction cells related to alumina dissolution. The bath temperature, alumina content, current and alumina temperature were chosen as the design parameters. The content of cumulative dissolved alumina(CCDA) and the relative deviation from the target content(RDTC) were adopted as the responses. The interactive influence results show that increasing the bath temperature and alumina temperature, as well as decreasing the alumina content, can increase CCDA. Increasing the bath temperature and lowering the current are beneficial for obtaining a more uniform alumina distribution. The optimal operating parameters were determined to be as follows: bath temperature of 958.8 ℃, alumina content of 2.679 wt.%, current of 300 kA and alumina temperature of 200 ℃. 展开更多
关键词 aluminum reduction cell alumina dissolution response surface methodology desirability approach heat and mass transfer
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Gradient Step Method to Predict the Ozone Solubility in Water 被引量:1
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作者 Marco Aurelio Cremasco Vanessa Trevizan Mochi 《Journal of Environmental Science and Engineering(A)》 2012年第2期256-260,共5页
In this work it presents a strategy to obtain the ozone solubility in water by gradient step method. In this methodology, the ozone in mixture with oxygen is bubbling in a reactor with distilled water at 21℃ and pH 7... In this work it presents a strategy to obtain the ozone solubility in water by gradient step method. In this methodology, the ozone in mixture with oxygen is bubbling in a reactor with distilled water at 21℃ and pH 7. The ozone concentration on gas phase is continually increased after the saturation is reached. The method proposed is faster than conventional method (isocratic method). The solubility from the gradient method is compared with that values obtained from correlations founded in the literature. 展开更多
关键词 OZONE SOLUBILITY gradient step method isocratic method.
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Study of Dissolved Chlorofluorocarbons in Lake Washington 被引量:1
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作者 韩丽君 John L. Bullister David P. Wisegarver 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第2期171-179,共9页
Measurements of three chlorofluorocarbons (CFCs): trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and trichlorotrifluoroethane (CFC-113), along with methyl chloroform (CH 3CCl 3) and carbon tetrachlo... Measurements of three chlorofluorocarbons (CFCs): trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and trichlorotrifluoroethane (CFC-113), along with methyl chloroform (CH 3CCl 3) and carbon tetrachloride (CCl 4) were made in water samples from Lake Washington, using Electron Capture-Gas Chromatography (EC-GC). The samples were collected in mid-autumn, a period when the lake’s upper layer undergoes rapid cooling. At the time of sampling, a strong vertical temperature gradient was present in the lake, with surface temperatures of ~14℃, and near bottom (50 meters) temperatures of ~8℃. The concentrations of dissolved CFC-12 and CFC-11 increased with depth, as expected from the higher solubilities of these gases at lower temperatures. Atmospheric measurements made at the sampling site at the time of the cruise, showed that CFC-11 and CFC-12 saturations in the near surface samples were 100 % and 106%, respectively. For the deepest sample (52 meters) CFC-11 and CFC-12 saturations were 102 % and 126 %. Because the surface layer of the lake responds to changes in atmospheric CFCs on a time scale of several weeks, the higher than equilibrium concentrations of CFC-12 observed at the time of sampling may reflect earlier episodes of elevated levels of atmospheric CFC-12 in this urban area. High concentrations of dissolved CFCs in runoff or industrial effluent might also lead to elevated CFC levels in the lake. The cold, deep water of Lake Washington is relatively isolated from the effects of surface gas exchange except during winter, and the supersaturations observed in the deep layer may reflect periods of elevated atmospheric CFC-12 levels from the previous winter season. These results were compared to summertime profiles of CFC-11 and CFC-12 made in 1994. 展开更多
关键词 chlorofluorocarbons(CFCs) SOLUBILITIES saturations Electron Capture-Gas Chromatography (EC-GC)
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Effects of temperature and phosphoric acid addition on the solubility of iron phosphate dihydrate in aqueous solutions 被引量:5
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作者 Tongbao Zhang Yangcheng Lu Guangsheng Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第2期211-215,共5页
As important controlling factors for the synthesis of iron phosphate materials by liquid-phase precipitation, the solubilities of iron phosphate dihydrate were systematically measured at H3PO4 concentrations from 1.13... As important controlling factors for the synthesis of iron phosphate materials by liquid-phase precipitation, the solubilities of iron phosphate dihydrate were systematically measured at H3PO4 concentrations from 1.13 wt% to 10.7 wt% temperature from 298.15 to 363.15 K, and atmosphere pressure in this work. The solubility was found to increase 5 orders of magnitude or more with increasing the concentration of phosphoric acid, and de- crease 1 to 2 orders of magnitude with increasing the equilibrium temperature. The phosphoric acid addition and temperature were found to affect the solubility of iron phosphate dihydrate by the formation or dissociation of coordination species, which could further accelerate the phase transformation from the amorphous iron phosphate dihydrate to orthorhombic iron phosphate dehydrate by dissolution-recrystallization mechanism. The high dependences of the solubility of iron phosphate materials on HsPO4 concentration and temperature were also well predicted by calibration equations, which are meaningful for quantitatively understanding the precipitation process and sequential crystalline structure transformation and pursuing a rational strategy for syn- thesizing specific iron phosphate materials. 展开更多
关键词 Iron phosphateSolubilityAqueous solutionPhosphoric acidTemperature
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Optimized One-Step Preparation of a Bioactive Natural Product,Guaiazulene-2,9-dione
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作者 CHENG Canling LI Pinglin +6 位作者 WANG Wei SHI Xuefeng ZHANG Gang ZHU Hongyan WU Rongcui TANG Xuli LI Guoqiang 《Journal of Ocean University of China》 SCIE CAS 2014年第6期1000-1004,共5页
We previously isolated a natural product, namely guaiazulene-2,9-dione showing strong antibacterial activity against Vibrio anguillarum, from a gorgonian Muriceides collaris collected in South China Sea. In this exper... We previously isolated a natural product, namely guaiazulene-2,9-dione showing strong antibacterial activity against Vibrio anguillarum, from a gorgonian Muriceides collaris collected in South China Sea. In this experiment, guaiazulene-2,9-dione was quantitatively synthesized with an optimized one-step bromine oxidation method using guaiazulene as the raw material. The key reaction condition including reaction time and temperature, drop rate of bromine, concentration of aqueous THF solution, respective molar ratio of guaiazulene to bromine and acetic acid, and concentration of guaiazulene in aqueous THF solution, were investigated individually at five levels each for optimization. Combined with the verification test to show the absolute yield of each optimization step, the final optimal condition was determined as: when a solution of 0.025 mmol m L-1 guaiazulene in 80% aqueous THF was treated with four volumes of bromine at a drop rate of 0.1 m L min-1 and four volumes of acetic acid at-5℃ for three hours, the yield of guaiazulene-2,9-dione was 23.72%. This was the first report concerning optimized one-step synthesis to provide a convenient method for the large preparation of guaiazulene-2,9-dione. 展开更多
关键词 azulene derivative guaiazulene-2 9-dione optimization preparation
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Synthesis and Conductivity of Oxyapatite Ionic Conductor La10-xVx(SiO4)6O3+x 被引量:3
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作者 袁文辉 申荣平 李莉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期328-332,共5页
Apatite-lanthanum silicate has attracted considerable interest in recent years due to its high oxide ion conductivity.In this paper,V-doped samples La10-xVx(SiO4) 6O3+x(0≤x≤1.5) were prepared by sol-gel method and t... Apatite-lanthanum silicate has attracted considerable interest in recent years due to its high oxide ion conductivity.In this paper,V-doped samples La10-xVx(SiO4) 6O3+x(0≤x≤1.5) were prepared by sol-gel method and the influences of V-dopant content on calcining temperature and conductivity were reported.The samples were characterized by thermal analysis(TG-DSC) ,X-ray diffraction(XRD) and scanning electron micrograph(SEM) . The apatite was obtained at 800°C,a relatively low temperature in comparison to 1500°C with the conventional solid-state method.The ceramic pellets sintered at 1200°C for 5 h showed a higher relative density than La9.33Si6O26 pellets sintered at 1400°C for 20 h.The conductivities of samples were measured by electrochemical impedance spectroscopy.The conductivity was improved with the increase of V-dopant content on La site. 展开更多
关键词 oxide ionic conductor sol-gel method interstitial oxygen ion conduction oxyapatite
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Study on Extraction and Conversion Annatto (Bixa orellana L.) Color into Norbixin to Prepare Food Grade Water-Soluble Norbixin Powder
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作者 Tran Thi Ha Dao Phan Thoai +1 位作者 Le Thi Thu Thuy Phan The Dong 《Journal of Life Sciences》 2017年第2期97-104,共8页
Response surface methodology was used in this research to optimize the technical parameters of the extraction and conversion color compound in armatto seeds into norbixin. Parameters affected the extraction efficiency... Response surface methodology was used in this research to optimize the technical parameters of the extraction and conversion color compound in armatto seeds into norbixin. Parameters affected the extraction efficiency and norbixin recovery yield were solvent concentration, rate of solvent/seed, incubation time, and incubation temperature. The optimization results including: concentration of ethanol is 51.82°; concentration of NaOH is 0.52 M; ratio of solvent/seed is 7.1/1; incubation time is 33.12 minutes, incubation temperature is 58.6℃, and the rate of 36% HCl/color solution is 0.5/5 (v/v). 展开更多
关键词 Achiote Bixa orellana L. BIXIN norbixin EXTRACTION CONVERSION food color.
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Enrichment of Semi-Volatile Organic Acids from Aqueous Solutions by Multiple-Effect Membrane Distillation 被引量:5
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作者 班睿 刘苗苗 +2 位作者 秦英杰 王焕 崔东胜 《Transactions of Tianjin University》 EI CAS 2012年第5期320-329,共10页
Multiple-effect membrane distillation (MEMD) process for enriching semi-volatile organic acids from their individual aqueous solutions was performed by using a hollow fiber-based air gap membrane distillation (AGMD... Multiple-effect membrane distillation (MEMD) process for enriching semi-volatile organic acids from their individual aqueous solutions was performed by using a hollow fiber-based air gap membrane distillation (AGMD) module with the function of internal heat recovery. Aqueous solutions of glyoxylic acid, glycolic acid, lactic acid, pyrnvic acid, malonic acid and glutaric acid were used as model feed. For a feed of 1% (mass fraction), each acid could be enriched for 8--20 times, which depended on the surface tension of the concentrate. The operation performance of MEMD process was characterized by permeation flux J, performance ratio PR and acid rejection rate R. The effects of cold feed-in temperature, heated feed-in temperature, feed-in volumetric flow rate and feed-in concen- tration on MEMD performance were experimentally evaluated. Maximum values of J, PR and R were 4.8 L/(h-m2), 9.84 and 99.93%, respectively. Moreover, MEMD process demonstrated a fairly good stability in a long-term experiment lasting for 30 d when aqueous solution of 4% (mass fraction) lactic acid was used as a feed. 展开更多
关键词 multiple-effect membrane distillation organic acid ENRICHMENT performance ratio STABILITY
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Preparation of Composite Phase Change Material Based on Sol-Gel Method and Its Temperature-Adjustable Textile 被引量:2
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作者 易世雄 马晓光 +1 位作者 张莹 李桦 《Journal of Donghua University(English Edition)》 EI CAS 2009年第3期284-289,共6页
In this study,the sol-gel method was introduced to prepare the composite phase change material (CPCM). The CPCM was added to fabric with coating techniques and the thermal activity of modified fabric was studied. In a... In this study,the sol-gel method was introduced to prepare the composite phase change material (CPCM). The CPCM was added to fabric with coating techniques and the thermal activity of modified fabric was studied. In addition,the thermal property and the microstructure of CPCM were also discussed in detail by means of polarization microscope and differential scanning calorimeter,respectively. According to the analysis of main influencial factors of the property of CPCM,the optimal preparing technique was determined. It was proved that CPCM could exhibit a good thermal property while phase transformation process took place,and a better appearance of the fabric modified with CPCM could be obtained due to the fact that in a warm circumstance,the liquid-state phase change material could be firmly enwrapped and embedded in the three-dimensional network all the time during the phase transformation. Besides,the fabric treated with CPCM had a high phase-transition enthalpy and an appropriate phase-transition temperature. As a result,a desirable temperature-adjustable function appeared. 展开更多
关键词 COMPOSITE phase change material SOL-GEL temperature-adjustable TEXTILE
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Mechanistic study on the cellulose dissolution in ionic liquids by density functional theory 被引量:3
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作者 姚莹莹 李垚 +4 位作者 刘晓敏 张晓春 王键吉 姚晓倩 张锁江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第11期1894-1906,共13页
Ionic liquids (ILs) have attracted many attentions in the dissolution of cellulose due to their unique physicochemical properties as green solvents. However, the mechanism of dissolution is still under debate. In th... Ionic liquids (ILs) have attracted many attentions in the dissolution of cellulose due to their unique physicochemical properties as green solvents. However, the mechanism of dissolution is still under debate. In this work, computational investigation for the mechanisms of dissolution of cellulose in [Bmim]Cl, [Emim]C1 and [Emim]OAc ILs was performed, and it was focused on the process of breakage of cellulose chain and ring opening using cellobiose as a model molecule. The detailed mechanism and reaction energy barriers were computed for various possible pathways by density functional theoretical method. The key finding was that 1Ls catalyze the dissolution process by synergistic effect of anion and cation, which led to the cleavage of cellulose chain and formation of derivatives of cellulose. The investigation on ring opening process ofcellobiose suggested that carbene formed in ILs played an important role in the side reaction of cellulose, and it facilitated the formation of a covalent bond between cellulose and imidazolium core. These computation results may provide new perspective to understand and apply ILs for pretreatment of cellulose. 展开更多
关键词 Ionic liquidsCelluloseDissolution mechanism
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Research on the High-Strength Coating Preparation Methodology based on Acid Catalytic and Sol-Gel Method
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作者 Songyuan Yao 《International Journal of Technology Management》 2015年第10期126-128,共3页
In this paper, we conduct research on the high-strength coating preparation methodology based on acid catalytic and Sol-Gel method. This method has been widely used in the preparation of various functional thin film, ... In this paper, we conduct research on the high-strength coating preparation methodology based on acid catalytic and Sol-Gel method. This method has been widely used in the preparation of various functional thin film, film and protective film structure, etc. As a result of sol gel process continuously broaden the application field, this method has been more and more get the favor of people. Compared with other traditional preparation methods of inorganic material, sol-gel process has many characteristics. To adjust the solution acidity and add a small amount of acid or alkali can have the effect of" catalyst, its reaction process on sol to get and gel structure may also be affected. Our research analyze the topic theoretically and numerically which is meaningful. 展开更多
关键词 HIGH-STRENGTH Sol-Gel Method Coating Preparation Acid Catalytic.
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