响应面法优化甘肃平凉牡丹籽超声-微波提取工艺的研究

以甘肃平凉油用牡丹为籽原料,以单因素实验结果作为研究基础,对超声-微波协同提取时间、超声、微波的功率、温度、料液比等影响因素进行试验,应用中心组实验设计方案,以牡丹籽得油率为响应值,进行超声-微波协同萃取牡丹籽油,找出了影响提取牡丹籽油的交互因素：以石油醚为提取溶剂时,选择1∶6～1∶9范围内的料液比,用400～800 W的微波在30℃～50℃下辐照6～8 min,同时在480～560 W超声功率下振荡10～20 min,牡丹籽粗油得油率最高为34%,微波温度和功率、超声功率和振荡时间、超声功率和料液比以及振荡时间和料液比之间交互作用显著。     

超声强化溶剂提取车前草中总黄酮的研究

采用超声技术对车前草中总黄酮提取进行强化,选择料液比、超声提取时间、提取温度、超声功率四因素进行正交实验,得出影响总黄酮提取率大小的次序先后为：提取温度〉超声功率〉超声提取时间〉料液比。在实验参数的基础上,为了获得较高的提取率和节省溶剂用量,各因素的优化工艺参数为：料液比1：20,超声提取时间30min,超声提取温度为50℃,超声功率为200W,在这个最佳条件下试验,总黄酮的提取率为0．645％。相对常规回流提取法而言,采用超声法提取具有快速、节省溶剂、节省时间、提取的有效成分含量较高等优点。     

微波促进甘草酸的提取

微波辅助萃取技术近年来不断用于药物有效成分的提取,本实验以新疆甘草的粗粉为原料,用乙醇作溶剂,用微波辅助萃取法提取甘草酸,并研究了不同实验条件,如作用时间、不同的乙醇浓度、液固比、温度和微波功率对微波辅助萃取甘草酸的影响,得到一优化条件：50％的乙醇溶液作溶剂,微波功率300W,作用时间10min,温度70℃,液固比20：1（ml／g）。与传统提取法进行比较,得出微波辅助萃取甘草酸比传统方法更节约时间,效率更高。     

超声对提取海藻二十二碳六烯酸和二十碳五烯酸的影响

二十二碳六烯酸(DHA)和二十碳五烯酸(EPA)具有许多重要的生理活性和营养学功能。通过实验研究了提取温度、料液比、超声功率、频率以及提取时间对超声提取海藻DHA和EPA影响和超声提取的效果,结果表明,适当提高提取温度、溶剂量、超声功率或延长提取时间,DHA和EPA提取率随之提高。当超声功率为50W时,随着超声频率增加,DHA和EPA提取率反而降低。相同料液比时,55℃超声法提取1h比65℃溶剂法提取2h的DHA和EPA提取率提高25%～44%。不同料液比时,当料液比为1:4.5,超声法提取1h,DHA和EPA的提取率分别为79.48%、81.52%;而溶剂法料液比为1:5.5,提取2h时,DHA、EPA的提取率分别仅为63.57%、64.87%。超声提取不仅降低了提取温度、减少了提取时间和提取溶剂量,而且使DHA和EPA提取率明显提高。     

超声-微波辅助酶法对小米SDF提取和物理性质的影响

目的为了提高小米中水溶性膳食纤维(SDF)的得率,实验采用超声-微波(U-M)辅助酶法提取小米SDF,并对提取工艺进行优化。方法以小米SDF的得率为测定指标,对微波功率、提取温度、提取时间、料液比等4个因素进行单因素试验,并利用正交试验对以上4个因素进行优化。对此条件下提取的SDF和采用传统酶法提取的SDF得率及其物理性质进行研究。结果得到了提取小米粉SDF的最优条件,微波功率为550 W,料液比(g/mL)为1:25,微波温度为55℃,微波时间为20 min,提取率为13.63%,比传统酶法提取的SDF含量提高了46.88%;通过对小米SDF物理性质的测定,发现超声-微波处理对小米SDF的持水力、膨胀力、持油力均有显著提高,分别提高了24.79%,25.16%,15.74%。结论通过超声-微波辅助酶法可以提高小米SDF的得率,对其物理性质影响显著。     

荸荠多糖的超声波辅助提取工艺

为提高荸荠多糖的得率,采用超声波辅助法提取荸荠多糖。通过单因素试验研究超声波功率、料液比、提取温度、超声处理时间、乙醇浓度对荸荠多糖得率的影响,确定荸荠多糖的最佳提取工艺。单因素试验结果表明,在本试验条件下,超声波功率为300W、料液比1：10、提取温度为50℃、超声时间25min时荸荠多糖得率最高。     

枸杞色素的闪式提取和超声-微波协同提取工艺

目的 以枸杞为原料,比较不同提取工艺对枸杞色素吸光值的影响,以确定枸杞色素的最佳提取工艺.方法 通过单因素试验和响应面法对枸杞色素的闪式提取和超声-微波协同提取工艺进行研究.结果 闪式提取枸杞色素的最佳工艺条件为料液比(g/mL)1︰13,提取电压113 V,提取时间112 s,该条件下枸杞色素吸光度为0.457;超声-微波协同提取枸杞色素的最佳工艺条件为料液比(g/mL)1︰16,微波功率613 W,提取温度55℃,提取时间32 min,该条件下枸杞色素吸光度为0.502.结论 对2种提取方法在最佳工艺条件下进行比较,超声-微波协同提取法提取枸杞色素的效果优于闪式提取法.     

沙棘籽中原花青素的提取工艺研究

本文以提取沙棘油后的沙棘籽渣作为原料,乙醇为提取液,采用大孔吸附树脂精制法提取沙棘籽原花青素。结果表明采用D3520型大孔树脂,用50％乙醇洗脱提取,温度30℃,料液比1：8（w／v）,连续提取12h（60mkq／次）,原花青素的提取率可达9．84％（以脱脂沙棘千重计）,纯度达39．18％。该方法对沙棘籽渣中原花青素具有良好的精制效果。     

微波辅助萃取纤维板中苯并芘的影响因素研究

以苯并芘的提取率作为评价指标,进行了微波辅助萃取纤维板中苯并芘的研究。结果表明:样品量为0.5g,以正己烷/丙酮(体积比1:1)为萃取溶剂在600W的功率下90℃微波萃取40min,萃取效果最好,对纤维板中苯并芘的提取率达到95%以上。与传统的索氏萃取法相比,具有提取率高、快速、高效、环保等优点。     

超声提取葵粕绿原酸研究

研究了超声强化提取葵粕绿原酸中主要参数-乙醇浓度、液料比、超声功率、超声辐照方式、超声提取时间以及超声提取次数等-对绿原酸萃取率的影响.通过在单因素实验基础上进行的三因素三水平的Box-Behnken实验,得到了优化的工艺条件:在乙醇浓度为70%、辐照方式占空比9s:6s、超声提取30min的条件下,液料比为27.3ml/g,超声功率为200W,提取3次,绿原酸的萃取率可达到98.87%.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

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