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31.
This study offers new insights into two-lift deposition of mature fine tailings under atmospheric drying. The interaction of newly added lift and former lift(s) was evaluated using column experiments in terms of volumetric water content, electrical conductivity (EC), hydraulic conductivity, geochemistry and microstructure. Water content and EC followed the same trend and decreasing of water content appears to be responsible for significant reduction in EC. Evaporation on top of the column reduced the water content to almost zero. The obtained results support the coupling between the hydraulic and chemical processes that should be considered by active operators. 相似文献
32.
BackgroundFunctional foods are a fastest growing sector of the food industry. The development of functional foods comprising omega-3 fatty acids and probiotic bacteria, through complex coacervation process is an emerging area of research and product development.Scope and approachWe reviewed relevant literature concerning the use of complex coacervation in microencapsulation, focusing primarily on the inclusion of probiotic bacteria and omega-3 oils into a single delivery format. This review covers advantages and disadvantages of the complex coacervation process to microencapsulate bioactive ingredients, viability of probiotic bacteria and oxidative stability of omega-3 oil during the complex coacervation process, the bioaccessibility of omega-3 oil and probiotic bacteria during simulated gastrointestinal conditions and in-vivo testings.Key findings and conclusionsThe review describes the advantages of co-encapsulation using complex coacervation followed by spray drying. It also describes the technological hurdles that need to be resolved for further development of industrial applications of co-encapsulation of probiotic bacteria and omega-3 lipids. The co-encapsulation concept has been widely used in pharmaceutical delivery systems, but is a relatively new concept in food ingredient stabilisation and delivery. There is a commercial need of co-encapsulation of multiple bioactive ingredients within a single microcapsules, due to decreased cost and enhanced product quality. Complex coacervation has been shown to be a useful method for the co-encapsulation of multiple unstable bioactive ingredients. Although in-vitro evaluation deliver useful bioavailability information, additional in-vivo and clinical trials are needed to determine the efficacy of bioactive release, particularly for microcapsules containing multiple bioactive ingredients. 相似文献
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Anastasia A. Ivanova Chi Phan Ahmed Barifcani Stefan Iglauer Alexey N. Cheremisin 《Journal of surfactants and detergents》2020,23(2):327-338
Surfactant flooding has widely been used as one of the chemically enhanced oil recovery (EOR) techniques. Surfactants majorly influence the interfacial tension, γ, between oil and brine phase and control capillary number and relative permeability behavior and, thus, influence ultimate recovery. Additives, such as nanoparticles, are known to affect surfactant properties and are regarded as promising EOR agents. However, their detailed interactions with surfactants are not well understood. Thus, in this work, we examined the influence of silica nanoparticles on the ability of surfactants to lower γ and to increase viscosity at various temperatures and salinities. Results show that the presence of nanoparticles decreased γ between n-decane and various surfactant formulations by up to 20%. It was found that γ of nanoparticles–surfactant solutions passed through a minimum at 35 °C when salt was added. Furthermore, the viscosity of cationic surfactant solutions increased at specific salt (1.5 wt.%) and nanoparticle (0.05 wt.%) concentrations. Results illustrate that selected nanoparticles–surfactant formulations appear very promising for EOR as they can lower brine/n-decane interfacial tension and act as viscosity modifiers of the injected fluids. 相似文献
36.
根据角接触球轴承自旋运动特征,同时考虑弹流润滑效应,建立角接触球轴承考虑自旋运动的弹流润滑模型;采用多重网格法求解弹性变形,利用有限差分法迭代求解雷诺方程,得到较为精确的数值解;分析不同赫兹接触压力、滚道表面粗糙度下自旋对角接触球轴承弹流润滑和油膜刚度的影响。结果表明:考虑自旋时随着Hertz接触压力、自旋角速度增大,油膜厚度减小,油膜压力增大,油膜承压区域呈细长状,并向接触中心靠近;随着滚道表面粗糙度幅值增大,油膜压力和膜厚均出现了波动,且考虑自旋运动时,轴承油膜厚度明显减小,油膜局部压力峰值更大;随着卷吸速度、润滑油黏度增大,油膜刚度减小,而考虑自旋运动时油膜刚度值更大;随着自旋角速度增大,油膜刚度逐渐增大。 相似文献
37.
L. J. Konwar D. Deka 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(6):601-607
In the wake of increasing environmental constraints, this work is aimed at developing a catalyst purely prepared from waste biomass source as the raw material. The catalyst is investigated for its applicability in transesterification of vegetable oil with the objectives: (i) to use waste shells of mollusk as raw material for the preparation of activated carbon and CaO; (ii) to use it as heterogeneous catalyst in the transesterification of waste cooking oil; (iii) to optimize the different parameters affecting the transesterification reaction; and (iv) to study its reusability. Under optimized conditions it was observed that a conversion >90% was possible and the catalyst could be reused five times with a slight loss in activity. This study indicates that the biomass source could also be used as a potential raw material in the synthesis of environmentally benign catalysts. 相似文献
38.
石油酸是原油和馏分油中普遍存在的腐蚀性物质,其主要成分为环烷酸并且含量可以高达90%以上。环烷酸具有羧酸的所有化学性质,所以常常造成严重的腐蚀,从而影响原油加工设备及油品使用设备的正常运行和使用寿命。随着近年来世界范围内高酸原油产量的逐渐增加,高原油及各种高酸值馏分油所带来的腐蚀与产品质量问题显得愈发严重,因此迫切需要开发出经济高效的脱酸技术与工艺路线。本文较为全面而详细地总结并评述了国内外原油及油品的各种脱酸技术方法。分析表明:目前所报道的各类脱酸工艺较多,其中工业应用的加氢脱酸效果虽好但是成本较高,而其他大多数脱酸方法都存在较多的缺点或不足,因此探寻一种绿色环保、经济高效并且具有较好普适性的油品脱酸工艺显得非常迫切而必要。酯化法脱酸具有加工工艺简单、不需要复杂的后继处理,几乎可以降低所有的高酸值原油和油品(轻质、重质馏分油以及渣油)的酸值,为原料油的进一步加工提供了方便。酯化脱酸工艺的关键在于高效催化剂的选择,而目前的催化酯化体系虽然脱酸率较高,但仍存在着反应时间较长的不足,相信通过反应过程强化等手段解决该问题以后,催化酯化脱酸工艺会被很快投入到原油及油品的脱酸实际工业生产中去。 相似文献
39.
随着液压夹具在机械加工中运用推广,该公司引用液压夹具多年来取得一定成效,文章针对转向油缸的铸造缸盖铣、钻序前后加工工装进行对比分析,重点突出应用全自动液压夹具后可提升装夹效率、加工质量以及降低劳动强度等,可以在不添置设备的情况下,满足产能提升的需求。 相似文献
40.
针对海上石油平台、海底输送管线维修的需要,提供了一种液压摩擦焊机液压和电器系统设计思路,通过参数计算、电液控制系统设计,研发了一种液压摩擦焊机,通过对DH38钢摩擦叠焊单元成型工艺试验,发现焊接接头拉伸强度达到了母材强度的76%以上,验证了液压摩擦焊机的可靠性能,通过该研究的应用,可对海上石油平台、海底输送管线的维修起到积极作用。 相似文献