土壤中石油污染物的脱附过程

文章中主要采用有机溶剂萃取法（OSE）对高浓度石油污染土壤进行修复，经过精馏操作，有效回收原油，建立脱附等温曲线，研究了石油污染物在土壤-有机溶剂两相间的迁移规律。     

High-Tg porous polyimide films with low dielectric constant derived from spiro-(adamantane-2,9′(2′,7′-diamino)-fluorene)

Porous polyimide (PI) films with low dielectric constants and excellent thermal properties have been a pressing demand for the next generation of high-performance, miniature, and ultrathin microelectronic devices. A series of novel porous PI films containing fluorenyl-adamantane groups were prepared successfully via thermolysis of poly(ethylene glycol) (PEG) added in the PI matrix. The cross-sectional morphologies of porous PI films showed closed pores with diameters ranging from 135 to 158 nm, which were uniform and regular in shape without interconnectivity. These porous PI films exhibited excellent thermal properties with a glass-transition temperature at 376 °C whereas the 5% weight loss temperature in air excess of 405 °C due to enhanced rigidity afforded by fluorenyl-adamantane groups. Accompanied by thermolysis content of PEG increasing from 0 to 20 wt %, the density of porous PI films decreased, and the corresponding porosity grew significantly from 0 to 11.48%. Depending on porosity, the dielectric constant and dielectric loss of porous PI films significantly declined from 2.89 to 2.37 and from 0.050 to 0.021, respectively. These excellent properties benefit the as-prepared porous PI films for application as interlayer dielectrics, integrated circuit chips, or multichip modules in microelectronic fields. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47313.     

Small‐Sized High‐Power PIN Diode Switch with Defected Ground Structure for Wireless Broadband Internet

This letter presents a small‐sized, high‐power single‐pole double‐throw (SPDT) switch with defected ground structure (DGS) for wireless broadband Internet application. To reduce the circuit size by using a slow‐wave characteristic, the DGS is used for the quarter‐wave (°/4) transmission line of the switch. To secure a high degree of isolation, the switch with DGS is composed of shunt‐connected PIN diodes. It shows an insertion loss of 0.8 dB, an isolation of 50 dB or more, and power capability of at least 50 W at 2.3 GHz. The switch shows very similar performance to the conventional shunt‐type switch, but the circuit size is reduced by about 50% simply with the use of DGS patterns.     

变频器调速装置节能浅析

1概述 近十多年来,随着电力电子技术、微电子技术及现代控制理论的发展,变频调速技术已经广泛地用于交流电动机的速度控制,其最主要的特点是具有高效率的驱动性能及良好的控制特性.它是一种高新技术电力节能装置,它通过改变（降低）电源工作频率,来降低动力设备（电机）的转速,减少设备的输出功率,达到输出功率与工作负荷的最佳匹配,实现节能目的,有效地提高了经济效益和产品质量.几乎可以说,有电动机的地方就有变频器,在一切需要进行速度控制的场合,变频器以其操作方便、体积小、控制性能高而获得广泛应用.     

动态规划原理在骨料用料方案设计中的应用

在砂石料场规划中常面临多供料点、多需料点条件下的用料方案设计问题。本文应用动态规划原理,提出了“多供点—多需点”物料调配优化计算方法及框图,编制了相应的计算程序。工程实例分析表明,该方法在骨料综合成本和弃料量等方面均优于常规方法,具有一定的应用价值。     

Study on Hydrocracking of VGO Derived from Kazakhstan-Russian Mixed Crude

1 Introduction With the successful completion of the construction of the China-Kazakhstan oil pipeline the refinery at Dushanzi Pet- rochemical Company will process the Kazakhstan-Russian mixed crude at full steam starting 2007. The high sulfur, nitro- gen and heavy metals contents in the Kazakhstan-Russian mixed crude would have a serious impact on the secondary processing units of the Dushanzi refinery, in particular on the distillate hydrocracking unit, which mainly operates on vacuum g…     

复杂土坝的渗流安全分析评价

根据福华山土坝的渗流观测资料,建立了测压管水位的回归统计模型,定量分析了各影响量(水位分量、时效分量)对测压管水位的影响效应。在此基础上,结合观测资料,采用有限元法反演了大坝各填筑区的渗透系数,并综合评价了大坝的渗流性态。     

Synthesis of amphiphilic magnetic microspheres by dispersion copolymerization of styrene and poly(ethylene oxide) macromonomer

Amphiphilic magnetic microspheres ranging in diameter from 5 to 100 µm were prepared by dispersion copolymerization of styrene and poly(ethylene oxide) vinylbenzyl (PEO‐VB) macromonomer (MPEO) in the presence of Fe₃O₄ magnetic fluid. The effects of various polymerization parameters on the average particle size were systematically investigated. The average particle size was found to increase with increasing styrene concentration and initiator concentration. It also increased with decreasing stabilizer concentration and molecular weight of MPEO. The content of the hydroxyl groups localized in the microspheres ranged from 0.01 to 0.2 mmol g^?1. © 2003 Society of Chemical Industry     

产出水处理设备的腐蚀和机械磨损

提供了能够延长与产出水举升、加工、处置和注入有关的油气生产设备使用寿命的成功经验和技术,并按照产出水的处理程序进行介绍,即从油藏中的液体进入井筒到举升到地面(井筒管理),地面生产/加工设备和处理/注入设备的整个处理过程.由于井筒是最主要的设备,多数作业成本都与将液体举升到地面有直接关系,因此要重点强调井筒的管理.通过减少井的事故(抽油杆、油管和泵)可以大大降低操作成本,延长边缘井的生产时间.地面处理成本包括如何使泄漏、漏出物清洗及原油携带量降到最低的费用.上述经验来源于2002年8月对Permian盆地上成功优化水处理成本的作业商进行的采访;已发表的油气技术文献;本文作者在油气作业领域的个人经验(31年以上).     

甲磺酸铜催化合成草酸二异戊酯

制备了甲磺酸铜催化剂,对其结构进行了IR和热重分析,并用于催化草酸和异戊醇的酯化反应。结果表明,甲磺酸铜具有催化活性高、稳定,易分离,重复使用性能优良,对环境友好的特点。最佳酯化工艺条件为:n(异戊醇):n(草酸)=2．8:1,w(甲磺酸铜)=0．3％,以过量的异戊醇为带水剂,回流反应2．0 h,酯化率可达到96．8％。