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1.
煤矿井下瞬变电磁法成为煤矿井下超前探测工作的重要手段,在矿井水害预测预报上发挥着很大的作用。随着矿井上组煤层资源的逐渐枯竭,煤矿开采资源逐渐延伸向下组煤层。同一井田范围内同煤层及其顶底板的岩性特征一般相差不大,瞬变电磁法在同煤层施工过程中接收到的物理背景场较为接近;而不同煤层及其顶底板岩性特征通常会有较大的差别,瞬变电磁法在不同煤层施工过程中会接收到差别较大的物理背景场。当矿井存在多煤层开采时,通过大量数据研究瞬变电磁法在不同煤层巷道探测中的响应特征规律,分析并掌握不同煤层条件对瞬变电磁法探测结果的影响,能够提高瞬变电磁法在多煤层探测成果的准确性。  相似文献   
2.
明确蒸汽爆破处理对苹果果胶乳化性的影响。对苹果果胶进行蒸汽爆破处理,研究汽爆压力和汽爆时间对果胶乳化活性和乳化稳定性的影响,并比较汽爆前后果胶粒径和果胶表观黏度,通过显微镜观察乳化液的微观结构。结果表明,果胶乳化活性和乳化稳定性随着爆破压力和爆破时间的增加而增加,与未汽爆处理的果胶相比,在0.6 MPa/120 s处理条件下,果胶乳化活性由21.05 m2/g增加至43.61 m2/g;乳化稳定性由89.60 min增加到125.92 min;乳化液平均粒径由143.1 μm减少为100 μm;乳化液表观黏度显著上升,显微观察显示汽爆后的苹果果胶乳化液滴更加均匀细密。蒸汽爆破处理苹果果胶提高了乳化性,使果胶乳化性整体改善。  相似文献   
3.
ABSTRACT

Fossil fuel resource is on the draining stage which leads to an increment in the cost of the petroleum products. Nowadays, research is focused on the development of environmental friendly lubricants which are derivatives of renewable sources. Inedible plant oil-driven bio-lubricants are environmentally friendly because they are non-hazardous, biodegradable, as well as there is no emission of toxic gases. This study involves the characterisations, advantages, as well as utilisation of inedible plant oil-driven bio-lubricants as an alternative for tribological applications. This report presents the status about the global lubricant market as well as potential outlook. Inedible plant oil-driven bio-lubricants bear high viscosity, high lubricity, and high viscosity index which can enhance the equipment service life and has the ability to carry high load and results in minimum amount of metal traces during combustion.  相似文献   
4.
Food induced viscosity can delay disintegration and subsequent release of API from solid dosage form which may lead to severe reduction in the bioavailability of BCS type III compounds. Formulations of such tablets need to be optimized in view of this postprandial viscosity factor. In this study, three super disintegrants, croscarmellose sodium (CCS), cross-linked polyvinylpolypyrrolidone (CPD), and sodium starch glycolate (SSG) were assessed for their efficiency under simulated fed state. Tablets containing these disintegrants were compressed at 10 and 30?KN, while taking lactose as a soluble filler. In addition to other compendial tests, disintegration force of these formulations was measured by texture analysis. Comparison of parameters derived from force – time curves revealed a direct relation of maximum disintegration force (Fmax) and disintegration force development rate (DFDR) with compressional force in fasted state, whereas an inverse relationship of Fmax and DFDR with compressional force was observed in fed state. The gelling tendency of disintegrants influenced the rate of release of API in simulated fed and fasted states when compressional force was changed. These observations recommend the evaluation of formulations in simulated fed state, in the development stage, with an objective of minimizing the negative impact of food induced viscosity on disintegration. Use of disintegrants that act without gelling or can counteract the effect of gelling is recommended for tablet formulations with reduced disintegration time (DT) and mean dissolution time (MDT) in fed state, respectively.  相似文献   
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6.
脲醛树脂(UF树脂)胶黏剂具有胶合强度高、制作简单、成本低廉、原料来源丰富等一系列特点,成为我国人造板生产的主要胶种,是市场上需求量最大的胶黏剂之一。但由于在固化时会放出刺激性的甲醛,游离甲醛高,在使用时严重危害人的健康。近年来,随着人们环保意识的提高,生产和使用低毒UF树脂胶势在必行。本文介绍了稀土氧化镧对脲醛树脂的改性过程并对改性后脲醛树脂胶的各项性能进行了测试。本实验通过在不同反应阶段加入稀土氧化镧,分别探讨它们对脲醛树脂胶黏剂性能影响。实验表明:在脲醛树脂胶中加入稀土氧化镧可以增加黏度、固化时间、固含量,并可以减少游离甲醛释放量。  相似文献   
7.
The objective of this study was the evaluation of different fibres (bamboo, acacia, potato or citrus) addition on texture, rheological and sensory properties of acid casein processed cheese sauces. Fibres used in production of sauces had an impact on the texture, viscosity, viscoelastic and sensory properties. The largest increase in viscosity was observed in products with addition of potato fibre, which have good water holding and adsorption capacity. Processed cheese sauce with the addition of citrus fibre was characterised by the highest values in general, and the increase of this feature in the tested samples was regular. Adhesiveness was the highest in products with 1% addition of every fibre. The lowest values of viscosity single shear, G′ and G″ moduli, among all tested, had sauces with acacia fibre. Moreover, they had the most thin liquid consistency, which was different from preferred one.  相似文献   
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9.
耿尧辰 《云南化工》2019,(6):106-107
对盐穴储气库系统密封性的测试与评价方法进行了详细介绍。测试方法选取原则、测试相关计算方法以及测试标准为储气库密封性测试的工程设计提供了详实的理论基础。  相似文献   
10.
Ultrasonic treatment could decrease the viscosity of heavy oil and previous study on had focused on one heavy oil sample and involved less on the influence of asphaltene content. This study examined the effect of asphaltene content on viscosity reduction rate by ultrasonication. A comparison on samples with various asphaltene content and vibration parameter was made. The results showed that the optimal vibration frequency might decrease as the asphaltene content increased, whereas the optimal vibration intensity and the optimal treatment time were suggested to be enlarged. A semi-quantitative correlation was matched, which helped for numerical simulation about ultrasonic treatment.  相似文献   
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