基于PT在线注入信号及神经网络跟踪小波变换模极大值变化的配电网故障定位方法

提出了一种配网单相接地在线故障定位的新方法。故障发生后从变电站母线在线向系统注入高频脉冲信号并获取线路上与注入信号相对应的反射行波,在电网结构已知的情况下,通过对反射波的分析进行故障定位。该方法不仅能检测故障点的电气距离,而且能确定故障所在的分支线路,还能通过调节注入信号的大小多次定位故障,提高定位的准确性。应用该方法进行故障定位不受接地电阻的限制。通过M atlab/S imu-link进行了建模与仿真分析,仿真结果验证了该方法的正确性。     

瓦斯地质编图在生产中的运用

通过矿井瓦斯地质编图，将井田划分为严重突出区、一般突出区、突出威胁区，按分区采取防突措施，指导了矿井的安全生产，获得了较好的社会效益和经济效益。     

电缆截面积计算中如何确定电导系数

在煤炭企业电缆截面积选择计算当中，如何确定电导系数的大小，是一个不能忽视的问题。本文经过分析、计算、论证给出了较为合理、准确的结果，为供电设计中电缆截面积的选择计算提供了重要的依据     

闹市区高楼的定向爆破实践

论述了高层砼框架结构建筑物定向爆破的设计与施工方法。介绍了剪力墙和楼梯的处理措施。对闹市区爆破网路设计与施工中应注意的问题进行了探讨。     

采煤技术及采煤方法的选择

介绍采煤技术的发展、采煤工作的现状及目前采煤工作中存在的一些问题，然后，对我国单一走向长壁采煤法采煤工艺、普通机械化采煤工艺、倾斜分层走向长壁下行垮落采煤法、倾斜长壁采煤法以及放项煤采煤法做了简要论述，最后，指出了采煤方法选择的原则以及具体措施。     

Prioritization methodology of dangerous substances for water quality monitoring with scarce data

Monitoring and control of dangerous substances discharged into receiving waters have attracted more attention lately. Since it is not possible to analyze every single substance, a prioritization methodology is needed for the selection of those to be monitored. Existing well-developed models require significant amount of data for reliable outcomes. This paper presents a methodology to prioritize the dangerous substances having adverse effects on freshwaters in Turkey, where data are scarce. Such a methodology will also serve as a solid model for other countries with limited background data. The adopted methodology enabled the elimination of chemicals to generate a candidate list composed of 608 substances among more than 5000 substances. Further screening and prioritization were conducted using different assessment methods (i.e., Total Hazard Value, Total Impact Value, Combined Monitoring-based, and Modelling-based Priority Setting) to obtain a proposed Final Candidate Specific Pollutants List of 150 dangerous substances. The proposed Candidate National Pollutant List of Turkey was established by combining 45 priority pollutants of the European Union with a list of candidate specific pollutants. According to the outcomes of this study, monitoring and controlling of 195 dangerous substances in freshwaters are recommended. Further detailed studies should be conducted in order to observe the actual levels of these dangerous substances in freshwaters followed by a review of the monitoring list accordingly. Moreover, further revisions might be required in the proposed list due to some possible versatile conditions in terms of sampling points (i.e., change in the location of industries).     

Effect of Hydrogen on Tensile Properties of Ultrafine-Grained Type 310S Austenitic Stainless Steel Processed by High-Pressure Torsion

This study addresses a hydrogen effect on the tensile properties of a type 310S austenitic stainless steel with ultrafine-grained structures produced by high-pressure torsion (HPT) and subsequent annealing. The mean grain size was reduced to ~85 nm by the HPT processing. The grain size was increased by the post-HPT annealing, but the grain size of ~265 nm was retained after annealing at 1023 K (750 °C). The tensile strength of ~1.2 GPa, which is approximately twice as much as that of the solution-treated specimen, was attained in the 1023 K (750 °C) post-HPT-annealed specimen. The elongation to failure was restored up to ~15 pct by the post-HPT annealing, although it was still insufficient in comparison with the ~55 pct elongation of the solution-treated specimen. There was no change in the tensile strength of the HPT-processed specimens and the post-HPT-annealed specimens by hydrogen charging with the hydrogen content in the range of ~20 to 40 mass ppm. The HPT-processed and the 773 K (500 °C) post-HPT-annealed specimens exhibited a ductility loss through the fully shear type fracture. The hydrogen charge into higher temperature post-HPT-annealed specimens with σ-FeCr precipitates led to a mild hydrogen embrittlement.     

Synergistic corrosion inhibition effect of 1-ethyl-1-methylpyrrolidinium tetrafluoroborate and iodide ions for low carbon steel in HCl solution

Investigation into the corrosion inhibition of low carbon steel in 0.1-M HCl solution by 1-ethyl-1-methylpyrrolidinium (EMTFB) and the effect of KI addition on the inhibition efficiency was carried out using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy and surface analysis (scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX)) techniques. Results show that EMTFB suppresses low carbon steel dissolution in the corrosive environment. Inhibition efficiency increased with the increase in EMTFB concentration. Addition of iodide ions to EMTFB raises inhibition efficiency from 75 to 98%. PDP results indicate that EMTFB affects majorly anodic reactions while EMTFB + KI act as cathodic-type inhibitor. The adsorption of EMTFB onto low carbon steel surface is by physical adsorption mechanism and follows Langmuir adsorption isotherm model. SEM and EDAX results confirm the adsorption of EMTFB alone and in combination with KI onto the steel surface.     

锚杆支护在综采拆除中的应用

本文介绍了祁南煤矿326综采工作面收作扩大断面采用锚网支护的施工技术，简要说明了采用矿工钢棚支护与锚网支护的优缺点，为综采工作面收作提供了一种安全可靠、施工简便的支护形式，并且提出了锚索加固基本原则。