HT-300裂化剂在油煤共炼固定床反应器中的应用

主要研究陕西延长石油(集团)有限公司450 kt·a~(-1)煤油共炼厂HT-300裂化催化剂的硫化和性能。结果表明,通过催化剂操作参数调整,可生产出高质量的石脑油和柴油,催化剂满足设计和设备长期运行操作要求。     

The effect of repellents on penetration into packaging by stored-product insects

Two known repellents of stored-product insects, DEET and neem, were compared to protein-enriched pea flour, defatted protein-enriched pea flour, and pea protein extract for their efficacy at reducing penetration and invasion by several common stored-product insects: Sitophilus oryzae (L.), Tribolium castaneum (Herbst), Cryptolestes ferrugineus (Stephens), and Oryzaephilus surinamensis (L.). The methods of preparation of pea extract affected the penetration of S. oryzae. Protein-enriched pea flour, DEET and neem reduced the penetration of S. oryzae, but defatted protein-enriched pea flour and pea protein extract did not. The number of S. oryzae, T. castaneum, C. ferrugineus and O. surinamensis entering pierced paper envelopes that contained wheat and were treated with DEET was reduced by 99%, 86%, 97% and 91%, respectively. Neem was less effective than DEET in reducing penetration and invasion of insects. Protein-enriched pea flour did not prevent insects entering pierced envelopes.     

边境地区广播电视信号收测研究

无线电频率是宝贵的资源,然而由于“模数同播”和与邻国频率共享等原因,边境地区省份的广播电视频率资源格外紧张.通过开展中俄边境地区广播电视信号收测工作,不但可以掌握无线广播电视频谱的实际使用情况,而且能为边境地区的频率协调工作提供有力的数据支撑.本文详细介绍了中俄边境地区广播电视信号收测工作,并对测试结果进行了分析和总结,对于今后的边境地区广播电视信号收测工作起到示范作用.     

An experimental study on the concrete hydration process using Fabry–Perot fiber optic temperature sensors

This paper describes the contribution of Fabry–Perot (FP) fiber optic temperature sensor to investigate the effects of concrete hydration process. The FP temperature sensor was easily fabricated by controllable chemical etching and adjustable fusion splicing. Detailed optical properties of the sensor were theoretically analyzed and temperature calibration experiments were performed. A sensor with a 90 μm cavity length was demonstrated to have a temperature sensitivity of 0.01 nm/°C and the linearity coefficient of 0.99. Furthermore, the FP sensor was embedded in the concrete structure for sensing the temperature change during the early age of hydration. During the concrete hydration experiments, the measured peak temperatures of the concrete specimens with different water-to-cement (w/c) ratios of 0.4, 0.5 and 0.6 were 51.42 °C, 52.88 °C, and 55.08 °C, respectively, corresponding to final setting times of 13.52 h (w/c = 0.4), 14.16 h (w/c = 0.5) and 15.2 h (w/c = 0.6) after concrete casting. Temperature profiles will be used for concrete hydration heat study, which will help us to have a better understanding of cement hydration behavior.     

考虑前馈作用的BTT导弹自动驾驶仪设计方法研究

针对BTT导弹自动驾驶仪的设计要求,文章提出了一种考虑前馈作用的导弹自动驾驶仪控制器设计方法。基于该型导弹三通道弹体数学模型,建立了自动驾驶仪控制系统数学模型。应用增益技术和递推设计方法,并基于过载稳定跟踪控制的设计要求,提出了一种全局非线性稳定控制策略,设计了连续的非线性自动驾驶仪,解决了该导弹俯仰通道的前馈问题;对于偏航通道,通过设计三通道协调控制律,将有前馈的自动驾驶仪设计问题转化为无前馈的设计问题;同时也利用滑模变结构控制原理解算出了横滚通道的舵偏角指令。数字仿真结果表明,所设计的自动驾驶仪控制系统可有效克服前馈问题所产生的稳态误差以及不确定性因素的影响,同时也提高了跟踪精度,并具有良好的动态特性和稳态品质。     

Smooth penalty function method for rigorous optimization of distillation processes

Integer decisions on stage numbers and feed locations, and global optimality are still challenging for rigorous optimization of distillation processes. In the present article, we propose a smooth penalty function method to address both these problems. The proposed method is based on the relaxation of the integer decision problem into continuous nonlinear programming (NLP) problem by adopting the bypass efficiency model developed by Dowling and Biegler. A smooth penalty term (SPT) is proposed and added to the total annual cost (TAC) function to form a new objective function, namely, the smooth penalty function. Using the new objective function, the problem is initially solved with negative weight coefficients for the SPTs regarding each column section to get an optimum near the global optimum of the SPT. Then, starting from this solution, the problem is solved again iteratively by increasing the values of the weight coefficients until all the stage numbers become integers. The performance of the method is validated by an illustrating problem and in three case studies, including a reactive distillation optimization problem.     

氮化硅基陶瓷连接技术的研究进展

陶瓷连接技术是结构陶瓷实用化的有效手段，焊料成分对连接体的性能具有决定性作用。本文主要从焊料成分选择的角度，总结了氮化硅基陶瓷连接技术的发展现状；并重点讨论了陶瓷／玻璃复合焊料在β-Sialon陶瓷连接中的应用。     

A novel multifunctional phosphorous and nitrogenous reactive flame retardant toward epoxy resins by one-pot method

Epoxy resin (EP) has attracted considerable attention in packaging, electronic devices, aerospace, and coatings fields owing to its remarkable chemical and physical performance. However, the inherent flammable performance and unfavorable brittle nature seriously restricted its application in sophisticated industry. Herein, an efficient reactive 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based flame retardant (DB-DAD) was prepared by a facile “one-pot” method. Due to their synergistic gas-phase and solid-phase flame-retardant effects, DB-DAD modified EP composites (EP/DB-DAD composite) easily achieved UL-94 V-0 ratings, and an EP/DB-DAD composite with a 0.32 wt% phosphorus content had an excellent (30.2%) limiting oxygen index. In addition, the amounts of heat and smoke decreased by 28.1% and 24.8%, respectively. Due to the introduction of long and flexible aliphatic chains, the EP/DB-DAD composites exhibited satisfactory mechanical properties, the flexural and tensile toughness of EP/6% DB-DAD were 82.5% and 62.2% higher than those of neat EP, respectively. Furthermore, EP/DB-DAD composite showed good transparency (>85%) and favorable UV shielding performance. The EP/DB-DAD composite with good comprehensive performance is extremely promising to accelerate EP application in high-tech industries.     

丁苯橡胶分子结构和炭黑对挤出流变行为的影响

通过毛细管流变仪并结合多种表征测试手段,研究丁苯橡胶分子结构和炭黑用量对胶料挤出流变特性的影响。结果表明:乳聚丁苯橡胶(ESBR)和炭黑补强ESBR胶料的表观剪切粘度分别大于溶聚丁苯橡胶(SSBR)和炭黑补强SSBR胶料;ESBR与SSBR的挤出稳定性相当,但炭黑补强SSBR胶料的挤出稳定性更优,挤出物外观质量较好;与SSBR相比,ESBR的分子链柔顺性和炭黑在其基体中的分散性更好,炭黑补强ESBR胶料中结合胶含量更高。