基于电压补偿原理的避雷器泄漏试验方法研究

直流参考电压U1mA和0.75倍U1mA下的泄漏电流测量是避雷器交接和例行试验项目之一。220 kV及以上避雷器常采用多节单元,由于避雷器制造工艺、均压环影响等原因,同一相避雷器各单元的伏安特性存在一定差异,当差异较大时,必须拆除引线,分单元进行避雷器直流泄漏试验。在对220 kV及以上避雷器伏安特性进行分析的基础上,提出了1种基于电压补偿原理的避雷器直流泄漏试验方法,设计了1台可调极性直流高压发生器。通过现场实用,验证了试验方法的有效性。     

Carbon dioxide capture by functionalized solid amine sorbents with simulated flue gas conditions

A novel solid amine sorbent was prepared using KIT-6-type mesoporous silica modified with tetraethylenepentamine (TEPA). Its adsorption behavior toward CO(2) from simulated flue gases is investigated using an adsorption column. The adsorption capacities at temperatures of 303, 313, 333, 343, and 353 K are 2.10, 2.29, 2.58, 2.85, and 2.71 mmol g(-1), respectively. Experimental adsorption isotherms were obtained, and the average isosteric heat of adsorption was 43.8 kJ/mol. The adsorption capacity increases to 3.2 mmol g(-1) when the relative humidity (RH) of the simulated flue gas reaches 37%. The adsorption capacity is inhibited slightly by the presence of SO(2) at concentrations lower than 300 ppm but is not significantly influenced by NO at concentrations up to 400 ppm. The adsorbent is completely regenerated in 10 min at 393 K and a pressure of 5 KPa, with expected consumption energy of about 1.41 MJ kg(-1) CO(2). The adsorption capacity remains almost the same after 10 cycles of adsorption/regeneration with adsorption conditions of 10 vol % CO(2), 100 ppm SO(2), 200 ppm NO, 100% relative humidity, and a temperature of 393 K. The solid amine sorbent, KIT-6(TEPA), performs excellently for CO(2) capture and its separation from flue gas.     

加压条件下固-液复合法制备Cu/Al复合材料

在加压条件下采用固-液复合法制备了Cu/Al复合材料,并对复合材料界面层的硬度、抗拉强度及微观组织进行了研究。结果表明,在加压条件下固-液复合法可以制备出抗拉强度达38.24 MPa且Cu/Al复合界面结合良好的复合材料;界面层硬度显著高于两侧基体硬度;界面层靠近铜侧区域容易出现断裂现象,生成的脆性相CuAl2是造成复合材料断裂的主要原因之一。     

40%三唑磷水乳剂的研制

本文介绍了40％三唑磷水乳剂配方的组成和制备方法,并对其性能进行了测试。试验结果表明：该方产品质量稳定,热贮（54℃±2℃,14d）分解率小于5％,各项指标符合水乳剂的要求。     

The effect of hydrogen addition on premixed laminar acetylene–hydrogen–air and ethanol–hydrogen–air flames

In the present work, the laminar premixed acetylene–hydrogen–air and ethanol–hydrogen–air flames were investigated numerically. Laminar flame speeds, the adiabatic flame temperatures were obtained utilizing CHEMKIN PREMIX and EQUI codes, respectively. Sensitivity analysis was performed and flame structure was analyzed. The results show that for acetylene–hydrogen–air flames, combustion is promoted by H and O radicals. The highest flame speed (247 cm/s) was obtained in mixture with 95% H₂–5% C₂H₂ at λ = 1.0. The region between 0.95 < X_H2 < 1.0 was referred to as the acetylene-accelerating hydrogen combustion since the flame speed increases with increase the acetylene fraction in the mixture. Further increase in the acetylene fraction decreases the H radicals in the flame front. In ethanol–hydrogen–air mixtures, the mixture reactivity is determined by H, OH and O radicals. For X_H2 < 0.6, the flame speed in this regime increases linearly with increasing the hydrogen fraction. For X_H2 > 0.8, the hydrogen chemistry control the combustion and ethanol addition inhibits the reactivity and reduces linearly the laminar flame speed. For 0.6 < X_H2 < 0.8, the laminar flame speed increases exponentially with the increase of hydrogen fraction.     

锆钛酸铅材料的Sol—Gel工艺合成及其电性能研究

以丁醇钛、乙醇锆、醋酸铅为原料,采用Sol-Gel工艺,成功地制备出锆钛酸铅陶瓷材料。本文主要对成胶规律、陶瓷材料的电性能进行了研究。结果表明:用该方法制备的陶瓷样品具有优良的介电和压电性能。     

加氢裂化装置长周期运行的影响因素分析

以中国石油长庆石化公司120×104t/a加氢裂化装置为例,对影响加氢裂化装置长周期运行的关键因素——原料氮硫含量、原料干点、氢分压、氢油比、反应温度、空速、循环氢中NH3含量等进行分析,提出了保证加氢裂化装置长周期安全、稳定运行的建议:严格监控上游常减压装置蜡油拨出率和操作稳定性,控制原料的馏程和干点;密切关注原料氮含量、硫含量、残炭及重金属含量等指标,特别是当氮含量偏高时,要注意调整精制器反应温度;由于未转化油与新鲜料混合作为反应总进料,因此应尽量稳定分馏操作,保证未转化油指标及进量的稳定;控制反应系统升温速率,保证升温速率不能太快;适当提高氢分压与氢油比;要密切关注反应系统中NH3的含量,特别是原料中氮含量升高时,应采取措施使其保持在尽量低的水平上。     

穆格莱德盆地构造地质特征与油气富集

穆格莱德盆地是非洲大陆内部的裂陷盆地,其构造演化过程可以分为3个阶段:1)早白垩世早期初始裂陷阶段;2)早白垩世晚期-晚白垩世继承性裂陷阶段;3)新生代坳陷阶段。晚白垩世末,中非大断裂的走滑运动对穆格莱德盆地有强烈的改造,使得图卢斯、巴加拉凹陷在裂陷伸展基础上叠加走滑构造变形,并使穆格莱德盆地南部发生明显的构造反转。初始裂陷阶段该盆地发育有半深湖-深湖相的泥岩,是较好的烃源岩;继承性裂陷阶段发育了多种类型的砂岩储层和厚层泥岩作为区域盖层,使穆格莱德盆地具有良好的油气勘探前景。盆地后期改造方式成为油气勘探评价关注的重要地质问题。     

Preliminary Structural Data Revealed That the SARS-CoV-2 B.1.617 Variant's RBD Binds to ACE2 Receptor Stronger Than the Wild Type to Enhance the Infectivity

The evolution of new SARS-CoV-2 variants around the globe has made the COVID-19 pandemic more worrisome, further pressuring the health care system and immunity. Novel variations that are unique to the receptor-binding motif (RBM) of the receptor-binding domain (RBD) spike glycoprotein, i. e. L452R-E484Q, may play a different role in the B.1.617 (also known as G/452R.V3) variant's pathogenicity and better survival compared to the wild type. Therefore, a thorough analysis is needed to understand the impact of these mutations on binding with host receptor (RBD) and to guide new therapeutics development. In this study, we used structural and biomolecular simulation techniques to explore the impact of specific mutations (L452R-E484Q) in the B.1.617 variant on the binding of RBD to the host receptor ACE2. Our analysis revealed that the B.1.617 variant possesses different dynamic behaviours by altering dynamic-stability, residual flexibility and structural compactness. Moreover, the new variant had altered the bonding network and structural-dynamics properties significantly. MM/GBSA technique was used, which further established the binding differences between the wild type and B.1.617 variant. In conclusion, this study provides a strong impetus to develop novel drugs against the new SARS-CoV-2 variants.