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。     

北宿煤矿疏放唐村矿井积水工程系统优化

本文介绍了北宿煤矿疏放唐村煤矿老空水的工程设计及采取的措施，达到了矿井疏放和排水要求，保证了安全生产。     

Anticonvulsant activity of furanocoumarins and the essential oil obtained from the fruits of Heracleum crenatifolium

The anticonvulsant activity of furanocoumarins, coumarin mixture and the essential oil obtained from the fruits of Heracleum crenatifolium was examined against maximal electroshock (MES)-induced seizures in mice. Bergapten showed significant anticonvulsant activity. The furanocoumarins isolated from the fruits of the plant were identified using thin-layer chromatography, melting points and spectroscopic methods (IR, MS, ¹H NMR) as isobergapten (1), pimpinellin (2), bergapten (3), isopimpinellin (4), sphondin (5) and byak-angelicol (6). The essential oil content of the fruits were found as 5.5%. Twenty-two compounds representing 99.3% of the essential oil obtained from the fruits of H. crenatifolium were determined and the major components were identified as octanol and octyl acetate (3.1% and 88.4% respectively) by GC and GC–MS.     

Inactivation of Penicillum expansum in sour cherry juice, peach and apricot nectars by pulsed electric fields

Inhibitory effects of pulsed electric fields (PEF) on Penicillum expansum inoculated into sour cherry juice, apricot and peach nectars were determined based on germination tube elongation, spore germination rate, and light and scanning electron microscopy (SEM) observations in this study. After inoculation of juice/nectar samples with P. expansum spores at the level of 10(5)-10(6)cfu/mL, the samples were processed by bench scale PEF pulse generator as a function of differing electric field strengths (0, 13, 17, 20, 23, 27, 30 and 34kV/cm) and processing times (0, 62, 94, 123, 163, 198 and 218mus). Results revealed that with an increase in electric field strength and processing time, germination tube elongation and spore germination rate were completely inhibited. Light and SEM observations revealed considerable morphological alterations in fungal conidia such as cytoplasmic coagulation, vacuolations, shrinkage and protoplast leakage. PEF processing of juice/nectars was demonstrated to be effective in inactivating P. expansum. To our knowledge, this is the first study confirming the inhibitory effects of PEF on germination tube elongation and spore germination rate of P. expansum in fruit juice/nectars.     

蔚县矿区奥陶系下统灰岩岩溶发育规律的研究

对矿区基底O1灰岩的溶隙、溶孔、溶洞进行综合分析,得出矿区的岩溶形态和岩溶发育程度特征。对研究奥陶系灰岩岩溶含水层的发育分布特征、富水特征及其地下水运移规律具有重要意义。     

煤矸石的资源化利用

介绍了煤矸石的基本组成及对水体,土壤,大气等的危害。介绍了几种煤矸石利用的主要途径及新的利用途径,并进行了经济技术分析,提出煤矸石资源化利用的建议。     

深井破碎围岩条件下煤巷锚杆构件合理配套

基于徐州矿区张小楼井24302工作面运输平巷的地质条件，在深井破碎围岩条件下进行了煤巷锚杆支护试验，介绍了锚网带索支护技术参数和不同构件配合支护的巷道矿压显现．根据顶板锚杆螺母撕裂和穿过托板与钢带导致的锚杆支护失效问题，在实验室完成了锚杆、托板、钢带和螺母等支护构件配合的力学性能试验．试验表明：直径20mm的螺纹钢锚杆杆体性能稳定，破断载荷均在186kN，杆体和螺母的螺纹配合完好，顶圆底四方螺母能与托板和钢带很好地配合，外接圆直径为38mm的六方螺母与托板和钢带不能很好地配合．深井高应力破碎围岩条件对锚杆支护系统中的锚杆、锚固剂、托板、钢带和螺母等构件的力学性能配合要求高，它们的力学性能应基于锚杆的破断力合理配套．     

输送带托辊的研制与开发

阐述输送带托辊的工作原理、系统结构及特点,介绍了输送带托辊的加工工艺流程以及技术应用情况,分析了制作工艺和使用效果。采用此工艺制造出来的输送带托辊,具有较高的同心度,密封性好,旋转轻快,经济耐用,很好地解决了现有托辊同心度不高,密封不严,容易进水、泥浆和灰尘,使托辊内的轴承磨损加快,托辊过早报废的缺陷,达到了降本增效的效果。     

试论节能球磨机专用滚动轴承的受力状态

初步分析了节能球磨机专用滚动轴承的受力状态,阐述了专用滚动轴承几个参数的修正系数,对该类轴承的校核提出了建议,并对部分应用实例进行了归纳总结。     

A PAM control method for a matrix converter based on a virtual AC/DC/AC conversion method

In this paper, a novel control method for a matrix converter is proposed. The proposed method is a PAM (Pulse Amplitude Modulation) control method based on a virtual AC/DC/AC conversion method. Output voltage amplitude is controlled by controlling a virtual DC link voltage with a virtual rectifier. Output frequency is controlled by a virtual inverter. First, the proposed method is explained. Next, the validity of the proposed method is confirmed through simulation and experiment using a 750‐W prototype matrix converter. Moreover, various characteristics of the proposed method and conventional virtual AC/DC/AC method are compared through experiment. As a result of the experiment, it has been understood that total harmonic distortion of output current and common‐mode voltage can be reduced compared with the case of using a conventional virtual AC/DC/AC conversion method. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(4): 88–96, 2009; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20601