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71.
针对荫营煤矿的特殊情况,阐述了荫营煤矿建立安全生产长效机制的重要性,指出问题的关键是安全意识的培养,而安全意识的培养又可分为自我安全意识的培养和生产安全意识的培养,必须长期坚持.  相似文献   
72.
矿井通风系统合理性的评价   总被引:2,自引:0,他引:2  
从技术方面、经济方面和安全程度方面分析了矿井通风系统合理性的影响因素,包括:结构合理性、用风地点角联数、风速超限状况、风机运转稳定性、矿井风压、风量供需比、设备购置费、巷道维护费、吨煤通风电费、矿山抗灾能力。选择层次分析法构建了矿井通风系统合理性评价模型,确定了各评价指标的权重并进行排序,得出了相关结论,即结构合理性、用风地点角联数、风速超限状况及风机运转稳定性对矿井通风系统合理性具有重要影响。  相似文献   
73.
通过机械模拟与相似材料模拟相结合的方法,对放顶煤顶板结构下的支承压力分布规律进行了分析。结果表明,放顶煤采煤法其支承压力分布形式与分层开采法类似,但在量值及影响范围上有增减。该研究结果对分析放顶煤矿压显现特征提供了依据。  相似文献   
74.
在对沁水煤田五阳矿区 600水平7303,7305两个试验工作面开采面积及排水资料进行归纳总结后,计算了采煤破坏的地下水动模数及静模数,并结合矿区地质及水文地质条件,计算了山西组砂岩的给水度。  相似文献   
75.
This review presents the possibility to use ion chromatography (IC) to analyse solids and brines deriving from treatment procedures of potassium salts. Qualitative and quantitative determination of ions samples has been used to make their chemical reconstruction. By using conventional calibration methods covering the whole concentration interval, analysis were not suitably accurate. During this process, the analysis is considered acceptable when the difference between the sum of the equivalents of cations and anions (ΔE) is ≤2%. For the process, a calibration method has been used employing four reference curves; each defined by three points corresponding to three standards purposely devised in our laboratory. The composition of the standards matched that expected for the samples from the different stages of the process reaction, after their usual sampling, dissolution and dilution. By comparing the conductivity of the analyte in the real sample to the conductivity of the same analyte in a standard, the effects of other analytes present in the medium are practically cancelled and need not be considered. The IC method results are in good agreement with conventional analysis methods (potentiometric titration, atomic absorption, gravimetric analysis).  相似文献   
76.
Turbidimetric method (TM), ion chromatography (IC) and inductively coupled plasma atomic emission spectrometry (ICP-AES) with and without acid digestion have been compared and validated for the determination of sulfate in mining wastewater. Analytical methods were chosen to compare the performance of a portable field turbidimetric instrument and to validate the underlying assumption utilized in conversion of total sulfur to sulfate during ICP-AES analysis. Accuracy and precision of analytical techniques were compared to one another using control and field samples collected from a mine site using the Bonferroni multiple comparison test. Effects of sample dilution, filter pore size and acidification on sulfate quantification were also studied. The results showed that IC and ICP-AES with and without acid digestion provided excellent recoveries in the case of control samples (within 90-110%). These analytical methods also showed lower relative standard deviation for both control and field samples. On the other hand, performance of the turbidimetric method was severely affected by sample dilution and acidification, and also revealed poor sulfate recoveries for control samples ranging from 0 to 83.5%. Analysis of variance (ANOVA) was used to evaluate the response (sulfate concentration) obtained from factorial design. Analytical method had significant effect (P < 0.0001) on the sulfate quantification. The interaction between determination method and sample dilution was more significant than other two-way interactions.  相似文献   
77.
结合寺河二号井煤层赋存条件,对15号层煤的工作面布置方案及回采实践进行了详细分析,总结了回采经验,以期对类似煤层的开采提供借鉴。  相似文献   
78.
煤矿监评系统中风险指数实时曲线的实现   总被引:1,自引:0,他引:1  
周宣赤  李俊韬  齐妍蕊 《科技信息》2009,(27):I0007-I0008
将煤矿井下作业环境的实时瓦斯浓度及评价指数以曲线方式在屏幕上动态显示出来,既便于实时观察数据的变化情况,亦利于煤矿相关人员研究煤矿安全生产的规律。介绍了专业图表制作工具ProEssentials控件及其特点,详细阐述了其在开发应用中的使用方法和具体步骤。并结合具体实例——山西某煤矿企业综合安全监评决策系统开发应用中的实时曲线要求,以VC6.0作为开发工具,在数据集成平台上,使用ProEssentials控件的DLL接口,实现了井下环境的瓦斯浓度及其风险评价指数的实时曲线的显示。该方法成功于工程实践中应用,有良好效果。  相似文献   
79.
介绍了庙湾煤矿14208工作面应用U+L型通风方式治理工作面上隅角瓦斯的经验.为处理回采工作面上隅角瓦斯问题提供了一种较好的方法.  相似文献   
80.
In this work, for the first time, an ion‐imprinted polymer was developed for selective extraction and determination of gold ions. To increase the sorbent efficiency, this polymer was coated on a novel nanoporous carbon‐based material, carbohydrate‐derived Max‐Planck Gesellschaft 1, which is also the first example of grafting imprinted polymer on nanoporous‐carbon material. These particles were applied successfully for preconcentration of ultratrace amount of gold ions, following determination by flame atomic absorption spectrometry. Some effective factors on the efficiency of gold ions extraction, such as concentration and volume of eluent, sample and eluent flow rates, and also effect of interfering ions especially palladium and platinum ions, were investigated. The LOD was determined to be 0.27 ng/mL. Furthermore, the precision of the method was calculated to be 2.14% under optimal conditions with recovery more than 97.3%. The technique was also used to determine the concentration of gold ions in mine stone samples with satisfactory results. The accuracy of this method was investigated by determination of gold ions concentrations in several reference materials with certified gold content.  相似文献   
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