用复分解法生产硫酸钾工艺分析

无氯钾肥是忌氯作物必须的肥料,我国硫酸钾矿藏贫乏,但芒硝类矿产资源丰富,结合国情分析了用复分解法生产硫酸钾工艺的特点,认为:用芒硝和氯化钾反应生产硫酸钾的前景广阔;硫酸铵-氯化钾法生产硫酸钾虽有诸多优点,但难于实现大规模生产;硫酸钙-氯化钾法生产硫酸钾的效益显著,但技术尚需继续完善。     

硫酸钾的国内外市场和生产工艺分析

分析了硫酸钾的国内外生产，消费及进出口情况，对我国硫酸钾生产发展前景进行了探讨，介绍了硫酸钾生产的几种主要的生产工艺。     

用石油炼制尾气替代水煤气作热源生产硫酸钾

介绍了用水煤气作热源生产硫酸钾工艺的缺点以及用石油炼制尾气作热源生产硫酸钾工艺的优点,通过3a的生产实践证明,用石油炼制尾气替代水煤气作热源生产硫酸钾的技术改造给公司带来了很高的经济效益和社会效益。     

国内硫酸钾供过于求氯化钾急待开发

近年来,国内农业部门对钾肥在作物生长中所起的作用越来越重视,特别是硫酸钾在烟草、水果、蔬菜等经济作物上的施用量不断增加,从而带动了国内硫酸钾生产,同时也剌激了硫酸钾的进口。目前,我国硫酸钾年生产能力约５０多万ｔ,其中仅台湾青上公司以及采用其技术在国内生产硫酸钾的企业的年生产能力就达３０万ｔ,再加上每年进口硫酸钾５０～６０万ｔ,资源已十分充裕。由于这几年烟草行业减产,对烟叶的需求量下降,造成对硫酸钾需求量减少,导致硫酸钾滞销,产品积压。目前我国已积压了进口和国产硫酸钾约３０万ｔ。生产硫酸钾的重要原…     

硫酸钾生产现状与发展建议

概述了国内硫酸钾生产研究现状,结合市场需求及资源情况提出了发展硫酸钾生产建议。     

硫酸钾生产消费及市场前景

我国硫酸钾生产自70年代以来,发展较快,相继开发出了芒硝法、缔置法、复分解法、氨化法、萃取法、离子交换法等生产工艺,并引进了曼海姆法生产技术,建设了30余个硫酸钾生产企业,已形成年产40万吨硫酸钾的生产能力,但由于种种原因,国内硫酸钾的年实际产量不足     

硫酸钾的国内外市场和生产工艺分析

分析硫酸钾（包括钾肥）的国内外生产、消费及进出口情况，对我国硫酸钾生产前景进行了探讨，介绍了硫酸钾的几种主要生产工艺。     

硫酸钾生产现状与发展建议

概述了国内硫酸钾生产研究现状,结合市场需求及资源情况提出了发展硫酸钾的生产建议。     

硫酸钾生产现状与发展建议

概述了国内硫酸钾生产研究现状,结合市场需求及资源情况,提出了发展硫酸钾生产建议。     

综述我国硫酸钾生产状况与生产前景展望

本文主要对我国硫酸钾生产的状况与生产前景进行系统综述,对我国工业硫酸钾的生产方法、工艺流程、生产工艺的上的特点以及对其未来发展前景进行分析研究;探讨如何从中国的国情出发,依据我们在资源上的优势,顺利发展中国硫酸钾市场;充分指出硫酸钾工业在我国生产发展中存在的问题,揭示硫酸钾工业的发展趋势。     

固定化酶用聚偏氟乙烯分离膜的制备及性能表征

为研究膜技术在生物反应器中的应用,选用聚偏氟乙烯为膜材料,聚乙二醇为添加剂,溶于不同的有机溶剂中,以相转化法成膜,以用于酶固定化。文章讨论了挥发时间、凝固浴温度及铸膜液温度等因素的影响,并对聚偏氟乙烯膜的通透性和固定化性能进行了研究。     

新型板网填料传质性能的研究

在５００ｍ ｍ 冷模实验塔内对２５０ Ｙ 型填料进行氧解吸试验,结果表明三层板网复合填料的分离效率明显高于单层板网填料,尤其在液气比低的工况下,效率可以倍增,和广泛应用的金属 Ｍｅｌｌａｐａｃ填料相比,板网复合填料的分离效率能高３０％ 左右。     

低成本复合高吸水性树脂的工业化研究

以丙烯酸为单体,凹凸棒黏土为复合组分,2,2-偶氮二异丁基脒二盐酸盐(V50)/过硫酸钾/抗坏血酸为引发剂,N,N′-亚甲基双丙烯酰胺为交联剂,采用水溶液自由基聚合法,在10 t反应釜内合成了速吸复合高吸水性树脂。结果表明,在w(单体)=42%(即单体质量占加入反应釜中所有物质质量的百分数)、引发温度50℃、w(发泡剂)=0.002%(以单体质量计)和w(交联剂)=0.12%(以单体质量计)的最优反应条件下,复合高吸水性树脂的吸水速率为43 s,2 kPa下吸生理盐水倍率为14.7 g/g。该工艺利用酸碱中和反应热及聚合反应热,可使胶体有效成分质量分数从42%提高到52%,降低了后续工段的蒸气耗量,与传统工艺相比,每生产1 t丙烯酸高吸水树脂总计可降低能耗达164万kJ。     

Characterization of a double emulsion system (oil-in-water-in-oil emulsion) with low solid fats: Microstructure

A double emulsion system [oil-in-water-in-oil (O/W/O)] with 16.3% (w/w) water and 83% (w/w) oil was prepared and stabilized using a novel method of mixing two oil-in-water (O/W) emulsions together. The first emulsion consisted of 85% (w/w) liquid canola oil, 14.4%(w/w) water, 0.5% (w/w) sodium caseinate, and 0.1% (w/w) lecithin and the second emulsion contained 73% (w/w) canola oil, 8% (w/w) palm-cotton stearin (50∶50), 0.2% (w/w) lecithin, 18.2% (w/w) water, and 0.6% (w/w) sodium caseinate. Mixing the two emulsions (50∶50) by weight produced a product with 79% (w/w) liquid canola oil and 4% (w/w) palm-cotton stearin. The two O/W emulsions were prepared separately at 50°C, mixed together at 45°C for 2–5 min, and then supercooled in a −5°C ice/salt bath while mixing at low shear rates (2,000–3,000 rpm). Under supercooling conditions the fat globules in the second emulsion (containing liquid oil and stearin) began to break down as a result of fat crystal growth and shearing action and release plastic fat. During this stage, the continuous aqueous phase underwent a phase transition and the emulsion viscosity dropped from 37,000–50,000 to 250 cP. The released plastic fat continued to harden as the temperature dropped and stabilized the first O/W emulsion (containing only liquid oil). The low shear rate mixing was stopped when the temperature dropped below 15°C and before the O/W/O emulsion hardens. Microstructural analysis of the first emulsion before and after supercooling showed essentially intact fat globules. The microstructure of the second emulsion before supercooling showed the same intact globules as the first emulsion, but after supercooling, an amorphous mass with only a few intact globules was seen. By mixing the two emulsions together and supercooling, a stable O/W/O emulsion was formed with plastic fat as the continuous phase and the first O/W emulsion as the dispersed phase.     

耐高温微胶囊化食用香精的研究

以明胶、阿拉伯胶为壁材,通过复合凝聚法可制备易于过滤的球状多核微胶囊。最佳的制囊工艺条件为：壁材浓度为1％,芯材：壁材（质量比）=2：1,明胶：阿拉伯胶（质量比）=1：1,pH值为4．0,甲醛：明胶（质量比）=1：1。     

含青霉素酰化酶的重组大肠杆菌的发酵培养

研究了含青霉素酰化酶的重组菌 Ｅ．ｃｏｌｉ Ａ５６ （ｐ Ｐ Ａ２２）发酵过程中环境因素对酶活的影响,考察了发酵液性质变化与酶活表达之间的关系,获得了酶活较高时的优化环境条件。结果表明,青霉素酰化酶在重组菌生长的平衡期后开始大量表达,苯乙酸作为限制性底物对青霉素酰化酶的合成起诱导作用     

Partition coefficient prediction of Baker's yeast invertase in aqueous two phase systems using hybrid group method data handling neural network

A hybrid GMDH neural network model has been developed in order to predict the partition coefficients of invertase from Baker's yeast. ATPS experiments were carried out changing the molar average mass of PEG(1500–6000 Da), p H(4.0–7.0), percentage of PEG(10.0–20.0 w/w), percentage of MgSO_4(8.0–16.0 w/w), percentage of the cell homogenate(10.0–20.0 w/w) and the percentage of MnSO_4(0–5.0 w/w) added as cosolute. The network evaluation was carried out comparing the partition coefficients obtained from the hybrid GMDH neural network with the experimental data using different statistical metrics. The hybrid GMDH neural network model showed better fitting(AARD = 32.752%) as well as good generalization capacity of the partition coefficients of the ATPS than the original GMDH network approach and a BPANN model. Therefore hybrid GMDH neural network model appears as a powerful tool for predicting partition coefficients during downstream processing of biomolecules.     

桉叶油微乳用于经皮给药的研究与评价

研究与评价了桉叶油作为油相在经皮给药微乳中的有效性。试验以非洛地平作为模型药物。分别以油酸、肉豆蔻酸异丙酯（IPM）和桉叶油为油相制备了9个水包油微乳处方,通过测定各处方物理化学参数和大鼠体外透皮试验研究,通过对比载药量、透皮速率、滞后时间等参数,得到最适宜的处方：w(桉叶油)为5%,、w(吐温-80)为27.5%、w(乙醇)为27.5%和w(水)为40%。最后对该处方进行了兔子在体皮肤刺激性研究。结果表明桉叶油有着显著的优点：乳化能力强、对亲脂药物溶解度大、透皮促进效果明显、稳定性好。但是桉叶油也有一定皮肤刺激性,不宜用量过大。     

驱油用高相对分子质量聚丙烯酰胺的制备

以丙烯酰胺和丙烯酸钠为原料，利用一种氧化还原引发体系，采用水溶液共聚法合成了高相对分子质量的聚丙烯酰胺。研究了反应温度、引发剂的添加量、单体总百分含量、单体配比及体系的ｐ Ｈ值等因素对聚合物相对分子质量的影响，确定了最佳的反应条件。     

Response surface methodology optimization applied to rubber tyre and plastic wastes thermal conversion

Thermal degradation was studied as a method to decompose mixtures of rubber tyre (RT) and different plastic wastes (PE, PP and PS) with the aim of producing a liquid fuel [1], as well as valuable chemical raw materials. An experimental set of runs was performed to establish the operational conditions that maximize liquid fraction production in a 1 litre batch reactor. Waste blends used were composed of 30% w/w RT and 70% w/w plastics (20% PE, 30% PP and 20% w/w PS). The complex hydrocarbon liquid mixture obtained during pyrolysis of these residues was highly dependent on experimental parameters, namely temperature, initial pressure and reaction time, which are the three most important factors affecting liquid yields. Regression analyses of experimental data were performed according to response surface methodology (RSM). As a result, experimental conditions optimized based on Factorial Design Methodology were 370 °C, 0.48 MPa for initial pressure and 15 min for reaction time. In order to validate the results obtained by the RSM model, three extra runs were conducted sequentially and average values were calculated and found to be: gas yield of 4.9% w/w, liquid yield of 81.3% w/w and solid yield of 12.7% w/w with an experimental deviation of 0.95%.