66 kV联络线备用电源自动切换装置功能的改进

为防止一次变全停、保证对用户连续可靠供电,针对66 kV系统双母线单主变压器运行的一次变和有小电源的末端变电所配有备用电源自动切换装置(简称备自投)的2种情况,通过系统故障后电流、电压的变化及继电保护装置动作情况对备自投装置动作影响的分析,提出备自投功能改进方案.即采取改变母差保护闭锁备自投方式及线路跳闸联跳主变一、二次断路器等改进措施,启动备自投,防止上述2种损失负荷情况的发生.     

Facile construction of highly efficient MOF-based Pd@UiO-66-NH2@ZnIn2S4 flower-like nanocomposites for visible-light-driven photocatalytic hydrogen production

Construction of metal-organic-frameworks-based composite photocatalysts has attracted much atten-tion for the reasonable band gap and high surface areas to improve the photocatalytic activity.In this study,the ternary heterojunction Pd@UiO-66-NH2@Znln2S4 nanocomposites were facilely prepared for the first time by a two-step method.The visible-light-promoted hydrogen production rate of 0.3％ Pd@UiO-66-NH2@Znln2S4 reaches up to 5.26 mmol g-1 h-1,which is evidently much higher than pure UiO-66-NH2,ZnIn2S4 and binary UiO-66-NH2/ZnIn2S4 composites.Such a huge improvement in the pho-tocatalytic performance is mainly attributed to the matched band gap of ZnIn2S4 and UiO-66-NH2,and the introduction of Pd NPs into photocatalysts that broaden spectral response range and promote the photon induced charge carrier separation.This work may provide a feasible approach for the design and construction of metal-organic-frameworks-based photocatalytic materials.     

Efficiently catalytic transfer hydrogenation of aryl and heteroaryl halides by ultrafine palladium nanoparticles confined into UiO-66

The hydrodehalogenation of aryl and heteroaryl halides (AHHs) is very crucial for academic and industrial applications. Herein, ultrafine palladium nanoparticles (Pd NPs) with the size distribution about 1.77 ± 0.35 nm, were in-situ synthesized and confined into the metal-organic framework of UiO-66 (named as Pd@UiO-66) by impregnation reduction method without tedious post-reducing step. Pd@UiO-66 shows excellent activity with a high conversion (>90%) efficiency in the catalytic transfer hydrogenation (CTH) of AHHs under mild water systems utilizing ammonium formate as hydrogen donor. Furthermore, Pd@UiO-66 maintains highly excellent stability (conversion >95%) after 5 times reused cycles without losing catalytic activity and leaching Pd nanoparticles. This study supplies a new method for hybrid catalysts by immobilizing ultrafine Pd nanoparticles into crystalline MOFs, displaying efficient transform performance for halogen compounds by catalytic hydrogenation.     

A computational study of water in UiO-66 Zr-MOFs: Diffusion,hydrogen bonding network,and confinement effect

For chemical warfare agent removal, the humidity emerges as an unavoidable challenge that significantly affects the performance of metal–organic frameworks. In this work, via density functional theory calculations, ab initio molecular dynamics and classical molecular dynamics simulations, we investigate the structural and diffusion properties of water in the pristine defect-free UiO-66, one Zr-based metal–organic framework. Through the detailed analyses of the distribution probability of water in two different cages of UiO-66, the binding interaction between water and UiO-66, the hydrogen bonding networks and resulted localized water clusters, we gain a fundamental understanding of structural and dynamics properties as well as the concentration dependence of water in UiO-66. We anticipate those theoretical results could provide insight to the competitive adsorption of water and chemical warfare agents, which eventually shows the utmost importance for the design and development of the next generation porous materials with appropriate water properties in real-life applications.     

稠油降粘剂HP在塔河S66井的应用

报道了乳化降粘剂HP用于塔河油田S6 6井稠油开采的现场试验结果并作了分析。HP的主剂为改性酚醚表面活性剂 ,复配以表面张力改进剂和抗盐聚合物 ,在 80℃下可抗耐矿化离子的浓度高达 2 .2 6× 10 5mg/L(包括Ca2 + +Mg2 + 4 .3× 10 3 mg/L)。S6 6井原油基本不含水 ,含气一般～ 10 % ,5 0℃粘度 9.2Pa·s。该井用掺稀油工艺生产 ,产液量由泵排量决定 ,为～ 6 6m3 /d。在为时 2 2d的现场试验中 ,用矿化度 5 .6× 10 4mg/L、含Ca2 + +Mg2 +4 .3× 10 3 mg/L的井水配制的浓度 4 75 0～ 6 0 0 0m/L的HP溶液从环空连续注入井内 ,油水体积比逐渐由 6 0∶4 0变为 70∶30 ,HP加量以总液量计由 2 2 0 0mg/kg逐渐降至 14 0 0mg/kg。HP加量在 2 2 0 0～ 16 0 0mg/kg范围时 ,产出的O/W乳状液 35～ 36℃下的粘度为 17.5～ 2 0 .0mPa·s ,而掺稀油时产出原油的粘度为 30 0mPa·s。当油水比由 6 0∶4 0变为 70∶30时 ,稠油、气、水的产出量分别由 35 .6t/d ,3.96m3 /d ,2 6 .4t/d变至 4 1.6t/d ,4 .6 2m3 /d ,19.8t/d。在采用掺稀油工艺时 ,稠油和气产出量分别为 2 9.7t/d和 3.30m3 /d ,回采稀油量为 33.0t/d。在现场试验中井口油压略升并大体维持稳定 ,对产生这一现象的原因作了分析。图 1表 3参 1。     

尼龙66/蒙脱土纳米复合材料的绿色阻燃和力学性能

对蒙脱土进行有机化处理后，使用熔融插层法制备了绿色阻燃尼龙66／有机蒙脱土（OM-MT）纳米复合材料，表征了复合材料的力学性能及其阻燃性能。结果表明，少量纳米二氧化硅的加入能够在一定程度上改善力学性能，其冲击性能相对提高了38．9％。当OMMT：SiO2为3：1，APP：MA为1.2：1，ZnO：APP为1／12-1／1O时材料的极限氧指数提高了33．3％。     

HDPE/PA66原位复合材料的结构与性能

用挤出-拉伸-注塑法制得了增强HDPE/PA66原位成纤复合材料,以不拉伸的普通共混材料作对照,研究了PA66质量含量(cm)对PA66成纤性和材料拉伸强度（σt）及模量（E）的影响及其作用机制。结果表明,当cm由0增至25%时,原位形成的PA66纤维数量增多,纤维横向尺寸及其分散性在cm=15%前减小在其后增大;材料的σt、E在cm =15%时分别比纯HDPE提高45%和60%。熔体拉伸时分散相液滴的聚结-形变成纤是PA66纤维形态随cm变化的关键因素,分散相对基体增强效应与两相界面缺陷效应综合作用,分散相对基体增刚效应受分散相形态控制,分别是决定材料的σt~cm、E~cm关系的支配因素。     

A shear pan mill for preparation of ultrafine polyamide 66 powder using sodium sulfate ionic crystals as grinding aid

Fine polyamide 66 (PA66) powder was prepared in a shear pan mill that was designed and developed in our laboratories. In contrast with discontinuous impacts in the ball mill, the size reduction operation in the pan mill is characterized by application of uninterrupted strong shear forces on particles. It has been found that as compared to the ball mill, much finer pulverization of the polymer material is achieved in the pan mill, in spite of the high strength and ductility of the polymer. Sodium sulfate ionic crystals with hard and pointed edge were co-milled with PA66 to further cut the fine polymer particles into ultrafine powder (2–5?µm). Besides acting as a grinding aid, the ionic crystals also prevented conglutination and aggregation of the polymer powder. Furthermore, PA66 powder could be conveniently separated and purified from the co-milled grinding aid-polymer mixture by simple water washing and filtration. Thus, an energy efficient and environment-friendly technology has been developed to prepare the ultrafine plastic powder at room temperature. This process holds a good promise for commercial applications.     

聚酰胺66纤维的热稳定性研究

采用热重分析(TG)和热裂解气质联用(Py-GC/MS)方法研究了聚酰胺66纤维的热稳定性和热裂解机制。结果表明:聚酰胺66纤维在氮气气氛中的热分解过程为一步反应,热分解活化能为186.4 kJ/mol,470℃以上可完全分解,热稳定性良好。聚酰胺66纤维的热裂解产物主要是环戊酮,峰面积百分比达24.27%。     

纳米硫酸钡增强增韧尼龙66

通过熔融共混法制备了纳米硫酸钡增强增韧尼龙66复合材料。研究了纳米硫酸钡含量对增强增韧尼龙66复合材料力学性能的影响。结果表明，纳米硫酸钡对尼龙66有显著的增强增韧作用。尼龙66的韧性、刚性和强度随着纳米硫酸钡含量的增加先增后减，在纳米硫酸钡质量分数为3％时，力学性能最优；对比空白样，缺口冲击强度提高了17．1％，弯曲强度和模量分别提高了5．74％和11．57％，拉伸强度和模量稍有提高。