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1.
陶瓷中碱金属和碱土金属氧化物对三氧化二铁分解的影响   总被引:1,自引:0,他引:1  
实验研究了陶瓷原料中的碱金属、碱土金属、氧化铝对三氧化二铁分解的起始温度和分解量的影响,并采用TO—DTA和XPd3等方法分析了这些成分与三氧化二铁分解之间的机理。  相似文献   

2.
欧盟REACH法规对我国化学工业的影响   总被引:1,自引:1,他引:0  
对我国与欧盟进出口的贸易情况进行了介绍,指出欧盟REACH法规的生效和运行将对我国化学工业产生以下影响:①给我国化工产品及相关产品的出口造成障碍;②使我国从欧盟进口产品成本增加;③将打破目前国际化学品贸易平衡的局面;④消弱我国出口产品的竞争力;⑤具有影响人体健康及污染环境的产品有可能向我国转移.提出了一些对策和建议.  相似文献   

3.
2011~2012年世界塑料工业进展   总被引:1,自引:0,他引:1  
收集了2011年7月~2012年6月世界塑料工业的相关资料,介绍了2011~2012年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚氯乙烯、聚苯乙烯、ABS树脂),工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚),特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮),通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。  相似文献   

4.
王敏 《水泥技术》2008,(3):71-72
球磨机是广泛用于水泥、电力等工业中耗电量较大的设备,如何对其进行自动控制,使之保持在最佳状态下运行,是多年来的一项技术难题.本文提供的测量装料量(料位)并加以控制的方法,经实践证明足行之有效的.  相似文献   

5.
《上海化工》2008,33(4):41
瓦克化学股份有限公司在2007业务年度创造了销售额和利润新记录.尽管原料和能源成本大幅上涨以及坚挺的欧元所造成的汇率影响,这家总部设在德国慕尼黑市的化学集团实现了利息、税、折旧、摊销前利润(EBITDA)10.02(上年:7.86)亿欧元,比上年增加27%.  相似文献   

6.
历代的画家都把"三顾茅庐"当作一种流行的绘画题材,景德镇高级工艺美术师、艺术瓷厂美研所副所长江振生先生独具匠心,精心制作的瓷板"三顾茅庐"再现了这一历史题材故事,整幅画面作者用传统粉彩工笔加写实的手法画出了三国时期刘备三赴卧龙岗求贤诸葛孔明的故事,画面景物宏伟壮观,色彩浓丽鲜明,雪景人物相影相彰,给人以清新的视觉效果,巧印了罗贯中原著:"柴门半掩闭茅庐,中有高人卧不起.""一夜北风寒,万里彤云厚,长空雪乱飘,改尽江山旧."小桥、流水、庭院;古树、雪景、人物,好一幅诗景画意.  相似文献   

7.
刘丹 《中国涂料》2008,23(1):12-14
上海是中国涂料工业的发源地,上海涂料有限公司是上海涂料工业最具代表的一个大型企业。从1915年诞生的中国第一家涂料工厂——"上海开林造漆厂(原名:开林颜料油漆厂)"起,上海涂料有限公司经历了九十多个春秋,一直致力于涂料前沿技术的研究和开发,至今已发展成为规模一流、品种齐全、质量上乘、服务周到和潜力无限的现代化涂料集团,2006年公司销售额超过35亿元。在当前国内倡导节能环保理念,推广水性涂料的大环境下,作为全国涂料制造业效益十佳企业的上海涂料有限公司,旗下技术中心更是意识超前地研发出了一种既具有高品质乳胶漆的优点,又具有大理石和花岗石等材质装饰效果高雅大气、施工方便的全水性多彩外墙涂料,并已实现规模化生产。为使业界对该公司及其前沿新品有一个深入全面的了解,本刊特对其技术中心进行了专访。  相似文献   

8.
黄发 《玻璃与搪瓷》2006,34(2):62-63
1企业概况上海器皿模具厂创建于1927年,前身为黄发记机器厂,是全国第1家专业制造玻璃机械和玻璃模具的企业,原属上海轻工控股集团公司,2001年转制为股份合作制民营企业。现有员工85人,其中具有大专以上学历的21人,技术人员14人,具有中高级职称的11人。企业专业生产经营各类玻璃  相似文献   

9.
Advanced model-based control strategies,e.g.,model predictive control,can offer superior control of key process variables for multiple-input multiple-output systems.The quality of the system model is critical to controller performance and should adequately describe the process dynamics across its operating range while remaining amenable to fast optimization.This work articulates an integrated system identification procedure for deriving black-box nonlinear continuous-time multiple-input multiple-output system models for nonlinear model predictive control.To showcase this approach,five candidate models for polynomial and interaction features of both output and manipulated variables were trained on simulated data and integrated into a nonlinear model predictive controller for a highly nonlinear continuous stirred tank reactor system.This procedure successfully identified system models that enabled effective control in both servo and regulator problems across wider operating ranges.These controllers also had reasonable per-iteration times of ca.0.1 s.This demonstration of how such system models could be identified for nonlinear model predictive control without prior knowledge of system dynamics opens further possibilities for direct data-driven methodologies for model-based control which,in the face of process uncertainties or modelling limitations,allow rapid and stable control over wider operating ranges.  相似文献   

10.
陈志宏 《橡胶工业》2008,55(5):280-280
2008年3月20日,中国橡胶工业协会机头模具分会第七届会员代表大会在广东省揭阳市召开.根据中国橡胶工业协会的建议,会议一致推选广东巨轮模具股份有限公司为新一届理事长单位,总经理洪惠平任理事长.  相似文献   

11.
地黄中梓醇的超声提取-树脂分离纯化工艺   总被引:2,自引:0,他引:2       下载免费PDF全文
研究了地黄中梓醇的超声提取-树脂分离纯化工艺。结果表明,超声提取的最佳工艺条件为:提取溶剂采用68%(体积)的乙醇,液料体积(ml)质量(g)比5:1,超声时间36 min。考察了10种大孔树脂对地黄粗提液的分离纯化效果,其中以H103对梓醇的纯化效果最佳。通过实验进一步考察了H103的动态吸附性能,得到分离纯化的最佳工艺条件为:上柱液浓度为6.15 mg·ml-1,上柱液流速为1.0 ml·min-1,洗脱剂为75%乙醇,洗脱流速为0.5 ml·min-1,洗脱体积为3.33 BV(bed volume)。提取、纯化两步操作后梓醇纯度达到62.39%。  相似文献   

12.
超声波提取法对海燕总皂苷提取工艺的研究   总被引:2,自引:0,他引:2  
李敏晶  韩艳玲  刘远  谭成玉  孔亮 《广东化工》2010,37(8):69-70,74
采用超声波提取法从海燕中提取总皂苷。在考察单因素影响后,以溶剂浓度、提取时间、料液比、超声波功率及温度建立正交实验。比较超声波提取法与微波提取法和索氏提取法的提取率,结果表明:超声波提取法最优;影响超声波提取法提取率的主要因素为溶剂浓度与料液比,其次是温度和提取时间。超声波提取法提取海燕皂苷工艺的优选方案为:料液比1︰20,乙醇浓度85%,温度70℃,超声功率60 W,提取时间20 min。  相似文献   

13.
《云南化工》2016,(2):1-4
以脱脂后的香薷油粕为原料,采用超声波辅助提取法提取香薷中的黄酮,分光光度法测定黄酮含量。分析溶剂浓度、料液比、提取时间、提取温度等因素对黄酮提取率的影响,采用正交实验优化提取条件。结果表明,香薷黄酮提取率的影响因素大小顺序为:料液比超声时间乙醇体积分数超声温度;最佳条件为:乙醇体积分数60%,料液比1∶30 g/mL,温度60℃,提取时间30 min;在此条件下黄酮的提取率为4.17%。  相似文献   

14.
BACKGROUND: Uniform design was used to optimize the ultrasonic‐assisted extraction of cordycepin from cultured Cordyceps militaris. The peak area of cordycepin identified using high performance liquid chromatography (HPLC) at a detection wavelength of 260 nm was considered the detection index. Three factors, ethanol concentration, extraction time and volume ratio of solvent to sample were studied. Optimal quadric polynomial step by step regression was applied to process the experimental results. RESULTS: Results show that the main factors affecting cordycepin extraction yield were the volume ratio of solvent to sample, extraction time and ethanol concentration, in that order. Cordycepin extraction yield reached a peak with ethanol concentration 20.21%, extraction time 101.88 min, and volume ratio of solvent to sample 33.13 mL g?1. An extraction model was developed based on the findings. CONCLUSION: A direct, reliable and accurate assay has been developed for the quantification of cordycepin in cultured Cordyceps militaris by a HPLC‐DAD method. The validation procedure confirmed that this method is appropriate for the quality control of cordycepin. Results show that the uniform experimental design approach is useful for finding polynomial functions describing the relationships between variables and responses and to find the best experimental conditions for the extraction of cordycepin in the experimental domain considered. Copyright © 2007 Society of Chemical Industry  相似文献   

15.
In this paper, the extraction of ferulic acid, a pharmacologically active ingredient from the root of Angelica sinensis with ultrasonic extraction was investigated. Percolation and supercritical fluid extraction (SFE) were also employed to make comparisons with ultrasonic extraction. Three variables, which including the concentration of solvent, the ratio of solvent volume to sample (mL/g), and extraction time, were found to have great influence on ultrasonic extraction. The optimum extraction conditions were using pure ethanol with a ratio of solvent volume to sample 8:1 (mL/g) and extraction time of 30 min. Under the optimum extraction conditions, the extraction yield could reach 6.5% mass fraction, which was higher than that of SFE process with ethanol as co‐solvent and nearly a content of ferulic acid 1.0%; both the yield and the content of ferulic acid were higher than those obtained by percolation. Moreover, the time of ultrasonic extraction was significantly shortened. Overall, Ultrasonic extraction was shown to be highly efficient in the extraction of ferulic acid from Angelica sinensis.  相似文献   

16.
乙醇回流提取油茶蒲中的总多酚,考察了提取温度、提取时间、乙醇浓度和液料比对油茶蒲总多酚的提取效果的影响。结果表明,各因素对油茶蒲总多酚的提取效果的影响大小依次为:提取温度液料比乙醇浓度提取时间;油茶蒲总多酚的适宜提取工艺条件为:以50%的乙醇溶液为提取溶剂,液料比为20 mL/g,在70℃温度下回流提取3次,每次80 min。在此工艺条件下,总多酚提取量为71.13 mg/g。  相似文献   

17.
张卫佳  程红  李伟倩 《广东化工》2014,(7):55+52-55,52
以金银花为原料,采用乙醇为提取剂,提取了金银花中的绿原酸。通过正交试验优化了金银花中绿原酸的提取工艺,结果表明最佳工艺条件是:超声浸提温度为60℃,超声波功率为50%,乙醇浓度为40%,浸提时间为2 h,固液比为1∶90。在此条件下,绿原酸的提取率为8.03%。  相似文献   

18.
The extraction of ferulic acid, a pharmacologically active ingredient from the root of Ligusticum chuanxiong, with ultrasonic extraction was investigated. Percolation and supercritical fluid extraction (SFE) were employed to make comparisons with ultrasonic extraction. Three variables, which included the concentration of solvent, the ratio of solvent volume/sample (mL/g), and extraction time, were found to have a great influence on ultrasonic extraction. The optimum extraction was with pure ethanol with a solvent volume/sample ratio 8:1 (mL/g) and extraction time of 30 min. Under the optimum extraction conditions, the extraction yield could reach 8.8% which was higher than that using SFE with ethanol as co-solvent and a content of ferulic acid of 0.7%; both the yield and the content were higher than those obtained by percolation. Ultrasonic extraction significantly shortened the time required for the extraction process. Overall, ultrasonic extraction was shown to be highly efficient in the extraction of ferulic acid from Ligusticum chuanxiong.  相似文献   

19.
以油茶饼粕为原料,采用乙醇提取-丙酮沉淀法对茶皂素进行提取分离。以茶皂素纯度和得率为考察指标,对乙醇体积分数、液料比、提取温度、提取时间、提取次数、提取液浓缩程度和丙酮用量等工艺参数进行了单因素优化。结果表明:体积分数95%的乙醇为提取溶剂,乙醇与预处理过的油茶饼粕液料比为9:1(mL:g),提取温度为70℃,提取时间为4 h,提取次数为2次,提取液浓缩至刚好有固体析出,丙酮用量为4倍浓缩液体积量时提取分离效果较佳,得到的茶皂素纯度为85.17%,得率为9.82%。不同溶剂打浆对产品纯化效果的比较发现:丙酮、乙酸乙酯、无水乙醇、体积分数95%的乙醇作为打浆纯化溶剂用于提高茶皂素纯度效果均不明显。  相似文献   

20.
从大豆粉末中提取卵磷脂的超声辅助萃取新工艺   总被引:1,自引:0,他引:1  
采用超声波为辅助手段,以卵磷脂得率为评价指标,用乙醇提取大豆粉末中卵磷脂。结果表明,最佳提取工艺条件为:乙醇浓度为80%,提取温度为40℃,超声时间为50 min,固液比为1∶3.0(g/mL),萃取次数为2次时,可以有效地提取大豆粉末中卵磷脂达12.85%。  相似文献   

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