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1.
Dye removal using adsorption requires a proper process parametric study to determine its optimal performance characteristics. In this study, response surface methodology was employed for the removal of methyl orange (MO) from aqueous solution using activated carbon-commercial grade (ACC) as an adsorbent. Experiments were carried out as per Box-Behnken surface statistical design with four input parameters namely adsorbent dose (w: 5-20 g/l), contact time (t: 2-6 h), temperature (T: 25-55 °C) and pH (pH: 2-8). Initial MO concentration (Co = 100 mg/l) was taken as a fixed input parameter. Regression analysis showed good fit of the experimental data to the second-order polynomial model with coefficient of determination (R2) value of 0.9114 and Fisher F-value of 10.28. Optimization of w (15.75 g/l), t (4 h), T (40 °C) and pH (2) gave a maximum of 99.11% MO removal by ACC.  相似文献
2.
响应面法优化微波辅助萃取柠檬皮中果胶的研究   总被引:6,自引:0,他引:6  
该文以离子液体[BMIM]Cl(氯化1-丁基-3-甲基咪唑)水溶液为萃取剂,采用微波辅助萃取技术提取柠檬皮中的果胶,系统考察了[BMIM]Cl浓度、萃取温度、萃取时间和萃取溶剂体积等因素的影响,并通过响应面法对提取工艺进行了优化,得出最佳工艺条件为[BMIM]Cl浓度1.0 mol/L,萃取温度88℃,萃取时间9.6 min,每克干柠檬皮用萃取溶剂22.7 mL,在该条件下,果胶的提取率为24.68%,与拟合的二次回归模型预测值基本相符。  相似文献
3.
Structured lipids from menhaden oil were produced by enzymatic acidolysis in a packed bed reactor. Response surface methodology was applied to optimize the reaction. Lipozyme IM from Rhizomucor miehei lipase was the biocatalyst, and caprylic acid was the acyl donor. Parameters such as residence time, substrate molar ratio, and reaction temperature were included for the optimization. High incorporation of acyl donor and retention of high levels of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids in the original menhaden oil were obtained. Good quadratic models were obtained for the incorporation of caprylic acid and for the content of EPA plus DHA retained, by multiple regression with backward elimination. The coefficients of determination (R 2) for the two models were 0.91 and 0.87, respectively. The regression probabilities (P) were below 0.003 for both models. Also, the predicted values from the two models had linear relationships with the observed responses. All parameters studied had positive effects on the incorporation of caprylic acid, but only residence time and substrate molar ratio had negative effects on the content of EPA plus DHA retained. The optimal conditions generated from models were temperature =65°C, substrate molar ratio=4–5, and residence time=180–220 min. Incorporated caprylic acid did not replace DHA, but the content of EPA decreased somewhat with an increase in caprylic acid incorporation.  相似文献
4.
秸秆/淀粉发泡材料的制备与表征   总被引:5,自引:0,他引:5  
黄君  王华林 《安徽化工》2011,37(2):21-24
以秸秆为原料,加入玉米淀粉、甘油、胶黏剂、填充剂和交联剂后烘焙发泡,制得复合发泡体。分析发泡体的密度、力学性能以及自降解性能,通过Design Expert Version 7.0.0软件对实验进行中心组合设计。结果显示:NaOH浓度、淀粉、胶黏剂和交联剂添加量对发泡体密度的交互影响显著;发泡体为黄褐色,表面光洁,气孔均密;单因素实验显示反应时间为10~14小时,反应温度为65~67℃;降解性能可能与淀粉添加量和周围环境有关。  相似文献
5.
响应面法优化螺旋藻中叶绿素的超声提取工艺   总被引:5,自引:0,他引:5       下载免费PDF全文
童洋  肖国民  潘晓梅 《化工学报》2009,60(11):2813-2819
Chlorophylls were extracted by using ultrasonic from Spirulina platensis. Single factor examination and response surface analysis experiments were adopted to investigate the effects of extraction time, extraction solvent, solvent concentration, ratio of liquid to solid and extraction grade. The results showed that the optimal process parameters for this method were: extraction time of 56.5 min, ethanol concentration of 48.3% (vol) of ethanol/acetone solvent, and ratio of liquid to solid of 7. 9 ml·g-1. The optimized chlorophylls extraction yield was 1.28%. The comparison experimental results indicated that the yield of chlorophylls by ultrasonic extraction was higher than that obtained from conventional solvent extraction.  相似文献
6.
微波辐射相转移催化下合成大豆油蔗糖多酯   总被引:4,自引:2,他引:2  
用微波辐射技术,以大豆油脂肪酸乙酯和蔗糖为原料,十六烷基三甲基溴化铵作相转移催化剂,用两步法合成大豆油蔗糖多酯。用响应曲面分析法中的Box-behnken模型对影响大豆油蔗糖多酯产率的3个主要因素(催化剂质量分数、微波功率、反应时间)进行了优化。优化出的最佳合成条件为:微波功率433W,反应时间33min,x(催化剂)=2.3%。在该条件下蔗糖多酯的产率达88.81%,酯化度达6.5。  相似文献
7.
褐黄孢链霉菌纳他霉素发酵条件优化   总被引:3,自引:0,他引:3  
采用Plackett-Burman设计(Plackett-Burman Design,P-B)对影响褐黄孢链霉菌(Streptomyces gilvosporeus) ATCC 13326纳他霉素发酵的相关因素进行了评价,所选取的15个因素为可溶性淀粉、葡萄糖、黄豆饼粉、酵母抽提物、蛋白胨、牛肉膏、MgSO4·7H2O、KH2PO4、NaCl、CaCO3、种龄、接种量、装液量、初始pH值和发酵温度.在此基础上用最陡爬坡路径逼近最大响应区域,再利用中心旋转组合设计及响应面分析对影响纳他霉素产量的关键因素初始pH、发酵温度、KH2PO4、CaCO3、酵母抽提物、蛋白胨和种龄的最佳水平范围作进一步的研究和探讨,通过拟合得到了响应曲面函数,但该函数的驻点是鞍点,因此不具有全局的最大、最小值.最后通过约束优化得到较佳的实验点,在该实验点条件下纳他霉素的产量比基本培养条件下提高了2倍,达到4.5g·L-1.  相似文献
8.
Production of specific-structured lipids (SSL) by lipase-catalyzed interesterification has been attracting more and more attention recently. However, it was found that acyl migration occurs during the reaction and causes the production of by-products. In this paper, the elucidation of acyl migration by response surface design was carried out in the Lipozyme IM (Rhizomucor miehei)-catalyzed interesterification between rapeseed oil and capric acid in solvent-free media. A five-factor response surface design was used to evaluate the influence of five major factors and their relationships. The five factors, water content, reaction temperature, enzyme load, reaction time and substrate ratio, were varied at three levels together with two star points. All parameters besides substrate ratio had strong positive influences on acyl migration, and reaction temperature was most significant. The contour plots clearly show the interactions between the parameters. The migration rates of different fatty acids were also compared from three different sets of experiments during the lipase-catalyzed reaction. The best-fitting quadratic response surface model was determined by regression and backward elimination. The coefficients of determination (R 2) of the model were 0.996 and 0.981 for Q 2 value. The results show that the fitted quadratic model satisfactorily expresses acyl migration for the enzymatic interesterification in the batch reactor used.  相似文献
9.
响应面分析法优化生姜挥发油提取工艺   总被引:3,自引:0,他引:3  
徐秀泉  孙雪琴  邱晶波  田新全 《应用化工》2011,40(6):1035-1038,1044
在单因素实验的基础上,采用中心组合实验设计及响应面分析法优化了生姜中挥发油的水蒸汽蒸馏提取工艺。结果表明,提取时间(p<0.01),料液比(p<0.05)对挥发油提取得率具有显著影响。最佳工艺条件为:生姜干燥后粉碎过60目筛,加水15.6倍,水蒸汽蒸馏4.78 h。在此条件下,挥发油得率为2.00%,实验结果与模型预测值相符。  相似文献
10.
Optimization of enzymatic degumming process for rapeseed oil   总被引:2,自引:2,他引:0  
An enzymatic process optimization and a largescale plant trial for rapeseed oil degumming were carried out by a novel microbial lipase. Response surface methodology was used to obtain the desired data in the process optimization. Enzyme dosage, temperature, and pH were important determining factors affecting oil degumming. The optimal set of variables was an enzyme dosage of 39.6 mg/kg, a temperature of 48.3°C, and a pH of 4.9. The phosphorus content could be reduced to 3.1 mg/kg at the optimal levels of the tested factors. An enzymatic degumming plant trial was performed on a 400 tons/d oil production line. pH was found to play an important role in degumming performance. When the pH was 4.6–5.1, the corresponding phosphorus content of degummed rapeseed oil could be reduced to less than 10 mg/kg, which met the demands of the physical refining process.  相似文献
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