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K. A. Sevost’yanova A. V. Omasheva M. I. Baikenov E. M. Tazhbaev 《Solid Fuel Chemistry》2016,50(6):376-380
The analysis of coal tar as a by-product of a merchant-coke plant (Karaganda) was carried out for the use of this tar as a plasticizer of rubber compounds. The replacement of bitumen by this tar as a rubber constituent in a weight ratio of 1:10 showed that the kinetics of vulcanization was noticeably accelerated and rubber characteristics such as conditional tensile strength, hardness, freeze-proof factor, and relative residual deformation were improved. It was found that the derivatives of phenol as the constituents of this tar exerted a considerable effect on the acceleration of the vulcanization process. In connection with this, the dephenolization of the product was performed, and it was used in a rubber formulation in the same ratio; as a result, the best characteristics of frost resistance, resistance to a hostile environment (an isooctane–toluene mixture), and ultimate elongation were obtained. 相似文献
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Daniel Alonso-Alconada Antonia álvarez Olatz Arteaga Agustín Martínez-Ibargüen Enrique Hilario 《International journal of molecular sciences》2013,14(5):9379-9395
One of the most common causes of mortality and morbidity in children is perinatal hypoxia-ischemia (HI). In spite of the advances in neonatology, its incidence is not diminishing, generating a pediatric population that will require an extended amount of chronic care throughout their lifetime. For this reason, new and more effective neuroprotective strategies are urgently required, in order to minimize as much as possible the neurological consequences of this encephalopathy. In this sense, interest has grown in the neuroprotective possibilities of melatonin, as this hormone may help to maintain cell survival through the modulation of a wide range of physiological functions. Although some of the mechanisms by which melatonin is neuroprotective after neonatal asphyxia remain a subject of investigation, this review tries to summarize some of the most recent advances related with its use as a therapeutic drug against perinatal hypoxic-ischemic brain injury, supporting the high interest in this indoleamine as a future feasible strategy for cerebral asphyctic events. 相似文献
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聚醚羟基含量及其分子量的自动电位滴定快速测定 总被引:2,自引:0,他引:2
本文介绍了以乙酸酐为酰化剂,对甲苯磺酸为催化剂,乙酸丁酯为溶剂的乙酰化反应体系,并以此体系建立了一种快速简捷的羟基分析方法,在聚醚的生产和应用过程中具有较高的实用价值。 相似文献
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Population-balances are a powerful method to predict the population behavior of drops in chemical-engineering equipment such as solvent extraction columns. In such columns a complex interaction of different phenomena, namely drop sedimentation, mass transfer, drop breakage and coalescence as well as axial dispersion occurs. In this article the concept of drop-population balances is discussed in detail as well as possible solution methods. Also, a critical review of existing models accounting for breakage and coalescence taking place in extraction columns is presented. Future parts of this series will be devoted to modelling mass-transfer and sedimentation as well as on application of single-drop based modelling. 相似文献
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介绍了在石化装置中蒸汽管道疏水阀的作用、常见形式、疏水阀的选型计算以及疏水阀在实际使用过程中的常见故障解析及排除. 相似文献
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抗冻耐水增强白乳胶的研制 总被引:4,自引:0,他引:4
采用延迟加料的半连续乳液聚合技术研制了一种改性白乳胶,讨论了单体、引发剂、乳胶保护剂、改性剂及操作工艺条件对乳胶性能的影响。结果表明,用醋酸乙烯作主单体,丙烯酸作改性单体,聚乙烯醇作乳胶保护剂,邻苯二甲酸二丁酯作增韧增塑剂,过硫酸铵引发,乙二醇、硝酸铝改性调节,反应温度控制在85℃左右,反应6 h制备乳液,增强了白乳胶的剪切强度、耐冻耐水性。经实验检测,剪切强度为5.21 MPa,30℃水浸4 d不开胶,-5~-3℃不冻结。 相似文献