乙醇提取苍耳子油的工艺优化

分别用水浴法、水浴微波法、水浴超声波法提取苍耳子中苍耳子油,用正交实验优化3种提取方法的最佳提取条件,结果分别为水浴法:温度60℃,时间5 h,固液比1∶10 (g/mL),提取率为7.33%;水浴微波法:微波功率600 W,固液比1∶10 (g/mL),时间12 min,提取率为8.65%;水浴超声波法:超声波功率300 W,固液比1∶10 (g/mL),30 min,提取率为9.21%。水浴超声波法的提取率最高。     

冬青叶中黄酮类化合物提取方法比较研究

分别采用水浴提取法、水浴搅拌提取法和微波辅助提取法提取冬青叶中的黄酮类化合物,利用正交实验优化的3种方法的提取工艺条件为:①水浴提取法:提取温度70℃,时间120 min,固液比1∶12,乙醇浓度60%;②水浴搅拌提取法:提取温度70℃,时间60 min,固液比1∶12,乙醇浓度60%;③微波辅助提取法:提取温度70℃,时间20 min,固液比1∶8,乙醇浓度70%。最佳工艺下的提取率分别为3.96,4.18,4.92 mg/g,温度对提取率的影响最为显著。微波辅助提取法的提取率最高,大大缩短了提取时间,但是对实验设备要求较高,水浴搅拌提取法相比水浴提取法提取率提高幅度不大,且水浴提取法操作简便、节约成本,适合工业化大批量生产。     

冬青叶中黄酮类化合物提取方法比较研究

分别采用水浴提取法、水浴搅拌提取法和微波辅助提取法提取冬青叶中的黄酮类化合物,利用正交实验优化的3种方法的提取工艺条件为:①水浴提取法:提取温度70℃,时间120 min,固液比1∶12,乙醇浓度60%;②水浴搅拌提取法:提取温度70℃,时间60 min,固液比1∶12,乙醇浓度60%;③微波辅助提取法:提取温度70℃,时间20 min,固液比1∶8,乙醇浓度70%。最佳工艺下的提取率分别为3.96,4.18,4.92 mg/g,温度对提取率的影响最为显著。微波辅助提取法的提取率最高,大大缩短了提取时间,但是对实验设备要求较高,水浴搅拌提取法相比水浴提取法提取率提高幅度不大,且水浴提取法操作简便、节约成本,适合工业化大批量生产。     

一点红中总黄酮的提取与测定方法研究

文章采用正交实验的方法,以一点红中总黄酮得率为考察指标,对影响一点红总黄酮提取方法的因素进行了探讨,分别得出了用连续回流提取法和超声波提取法提取一点红中总黄酮的最佳实验条件。连续回流提取法:乙醇浓度为75%,回流时间为3 h,固液比为1∶25,总黄酮含量为8.773 mg·g-1;超声波提取法:乙醇浓度为65%,震荡时间为60 min,固液比为1∶20,总黄酮含量为9.945 mg·g-1。     

磨盘柿叶总黄酮的提取研究

采用乙醇法和半仿生法提取磨盘柿叶总黄酮,乙醇法最佳提取工艺:70%乙醇为溶剂,固液比为1∶10,回流时间为1h,提取温度为70℃。半仿生法最佳提取工艺:提取温度80℃,时间1h,固液比为1∶20。     

响应曲面法优化超声波辅助提取艾叶中总黄酮的工艺研究

以艾叶为原料,采用单因素实验与响应曲面分析法相结合,研究了超声波辅助提取艾叶中总黄酮的影响因素及最佳工艺条件。结果表明,超声波辅助提取艾叶中总黄酮的最佳工艺条件为:乙醇体积分数60%,提取时间60min,液固比为20∶1(mL·g-1),提取温度为40℃,艾叶中总黄酮的提取率为9.15%。与传统法相比,超声波辅助提取法显著提高了艾叶中总黄酮的得率,大大缩短了提取时间,该提取工艺稳定可行,具有明显的优势和很大的应用前景。     

超声辅助提取都匀毛尖绿茶与红茶中茶多酚的工艺研究

以乙醇作为溶剂,用超声波辅助提取都匀毛尖红茶和都匀毛尖绿茶中茶多酚,从超声提取的时间、提取温度、乙醇的提取浓度、固液比四个因素研究其对茶多酚提取率的影响。通过单因素试验的结果,利用正交试验对各因素进行分析。结果显示,都匀毛尖红茶与绿茶中茶多酚提取优化后的工艺条件为:红茶固液比为1∶30,用质量分数为60%的乙醇,在70℃条件下超声波辅助提取50 min,茶多酚的提取率可达14. 98%;绿茶固液比为1∶40,用质量分数为40%的乙醇,在70℃条件下超声波辅助提取50 min,茶多酚的提取率可达24. 93%。     

龙眼茶茶粕中茶皂素提取工艺的研究

以永泰龙眼茶茶粕为原料,考察乙醇浓度、浸提时间、料液比、浸提温度等因素对茶皂素提取的影响,并进一步考察了超声波辅助提取茶皂素的工艺条件。结果表明,茶皂素的最佳提取工艺条件为:浸提时间为2 h,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。超声波辅助提取茶皂素的最佳工艺条件为:超声频率为40 k Hz,超声功率为500 W,浸提时间为50 min,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。利用超声波辅助乙醇法提取茶皂素的得率为12.9%,茶皂素纯度为65.6%。     

龙眼茶茶粕中茶皂素提取工艺的研究

以永泰龙眼茶茶粕为原料,考察乙醇浓度、浸提时间、料液比、浸提温度等因素对茶皂素提取的影响,并进一步考察了超声波辅助提取茶皂素的工艺条件。结果表明,茶皂素的最佳提取工艺条件为:浸提时间为2 h,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。超声波辅助提取茶皂素的最佳工艺条件为:超声频率为40 k Hz,超声功率为500 W,浸提时间为50 min,乙醇浓度为75%,料液比为1∶4,提取溶液温度为80℃。利用超声波辅助乙醇法提取茶皂素的得率为12.9%,茶皂素纯度为65.6%。     

超声波/回流法浸提取葡萄渣中总黄酮的工艺研究

对超声波和乙醇回流法两种不同提取葡萄渣中总黄酮工艺进行了探讨,测定了葡萄渣中总黄酮的含量,实验证明：乙醇回流法提取的最佳工艺为：乙醇浓度80%,温度60℃,料液比1∶50（g：ml）,提取时间120 min;超声波提取工艺最佳条件为：乙醇浓度80%,超声波作用时间60 min,料液比1：50（g：ml）,温度为40℃;...     

底座连接口特征参数对显示器后壳注塑质量的影响分析

在Moldflow分析软件的基础上,对显示器后壳进行仿真研究,以翘曲变形量为质量指标,结合控制变量法进行单因素变动实验,保持注射工艺参数不变,研究显示器后壳底座连接口对制品翘曲变形的影响.对数据进行图表分析,结果表明显示器后壳尺寸定位68.58 cm(27英寸)时,底座连接口选用圆形,连接口位置距离底边26 mm,尺寸...     

The role of the symmetry and the flexibility of the anion on the characteristics of the nanostructures and the viscosities of ionic liquids☆

The transport properties of ionic liquids (ILs) are crucial properties in view of their applications in electrochem-ical devices. One of the most important advantages of ILs is that their chemical–physical properties and conse-quently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the“rigidity”, the order, and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be con-trolled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion.     

浅谈设备的性能与操作对胎面压出质量的影响

简要介绍了胎面压出的工作原理及工艺过程，对设备的配置及操作对胎面压出质量的影响进行了分析，并对压出过程中常见的质量缺陷、造成的原因以及解决措施提出了自己的见解。     

Investigation of the effects of fatty acids on the compressive strength of the concrete and the grindability of the cement

In cement industry, a great energy consumption has been observed during grinding of clinker. To reduce this consumption, some waste products have been used as grinding aids.In this investigation, the effects of sunflower oil (SO), oleic acid (OA), stearic acid (SA), myristic acid (MA) and lauric acid (LA) on the fineness and strength of the cement have been examined. These aids were added into clinker in certain ratios based on the cement clinker weight and the grinding has been done for a definite time at the same condition.All of the fatty acids used increased the fineness as compared with the cement without the grinding additives. SO and OA decreased the strength significantly, LA decreased it to a lesser extent and SA increased it definitely according to the common cement. But MA did not alter the strength of the cement as much as SA. In addition, the covering of the balls influences the grinding of cement clinker unfavourably.     

煤粉流动性对GSP气化炉气力输送的影响研究

针对GSP气化装置煤粉气力输送在试车阶段出现的煤粉锁斗下料不畅、发料罐输送性能不佳等问题,从原料煤性质和工业装置的改进方面出发,通过煤粉的流动性参数的测量与研究,分析出现上述工程问题可能的内在原因,并提出工业装置改进方法,为保证GSP煤粉气力输送工业装置的正常运行提供解决办法。     

关于建立火炸药安全数据库的探讨

由反映火炸药及其制品的危险性能和用于对它们的生产、储运系统进行安全评价数学模型出发,探讨了如何建立一个全面、实用的火炸药安全评估数据库。通过对此数据库内容、数据表示方法、数据搜索方法以及建立步骤的讨论,明确了该数据库的使用对象和主要功能。     

The effect of the length of the oxyethylene chain on the conductivity of the polyurethaneurea electrolyte

Polyurethaneureas (PUU), which were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), poly(ethylene glycol) (PEG), and 3,5-diaminobanzoic acid (DABA), were used as polyelectrolytes in this study. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to monitor the effect of the various kinds of PEG on the changes in morphology of PUU electrolytes corresponding to the concentration of lithium perchlorate (LiClO₄) dopants. The results of DSC and FT-IR indicate the Li⁺ ions coordinate with the soft and hard segments. Additionally, the crystallinity of the PEG soft segment and the ordered hydrogen-bonded urea carbonyl groups decreased with increasing salt concentration. Impedance spectroscopy (IS) measurements show that the PUU electrolyte with the high phase separation degree has the high ionic conductivity. The hard-segment T_g and the soft-segment T_m influence the conductivity behavior of polyelectrolytes with increasing measurement temperature.     

转子挤压组合凹模的应力分析

组合凹模的应力分析是一个非常复杂的问题，对其进行精确分析是解决模具寿命的关键。本文采用有限元分析软件Ansys对转子的组合凹模进行了分析，为转子组合凹模的优化设计提供了依据。     

Effect of the drafting force on the strength of the bottom of the spinneret

In spinning basalt fibres, the drafting force is in the same range as in spinning of glass fibres. The effect of the drafting force can not be considered in the calculation for the strength and rigidity of the bottom of the spinneret. __________ Translated from Khimicheskie Volokna, No. 5, pp. 47–50, September–October, 2007.