煤矿瓦斯压力及含量测定方法分析

在评价矿井危险性的工作中,如何准确掌握矿区瓦斯含量及压力是工作人员们面临的首要问题。对于一些无法直接测定煤层瓦斯含量、压力的矿区,我们采用间接测算法来获取瓦斯含量及压力值。本文以陕西省延安市某煤矿为例,采用间接法测定其瓦斯含量及压力。     

四棵树二号井瓦斯基本参数测定及涌出分析

煤矿瓦斯基本参数对矿井瓦斯治理工作有很大的指导意义。通过间接和直接法对四棵树二号井5#煤层瓦斯参数进行测定,得出分析区内A_5煤层瓦斯压力最大值为0.62MPa,A_5煤层瓦斯含量最大值为2.72m~3/t。煤层瓦斯随着深度的增加而增加。分析区域采掘区域瓦斯涌出在走向上分布不均匀。     

铁生沟煤业有限公司15采区二_1煤层瓦斯基础参数的测定

通过对铁生沟煤业有限公司15采区二1煤层瓦斯基础参数测定过程,以及测定方法和计算方法进行阐述,确定二1煤层瓦斯压力、瓦斯含量、钻孔瓦斯衰减系数、煤的坚固性系数f、煤层透气性系数等参数,这些基础数据是煤矿瓦斯综合治理的重要依据。     

煤峪口矿主采煤层瓦斯压力测试与分析

煤层的瓦斯压力是矿井瓦斯基本参数之一,准确测定煤层瓦斯压力具有重要意义。测压过程主要包括:选择测定地点和测定方法、开掘钻孔、封孔以及压力的观测确定。本文通过对煤峪口煤矿的瓦斯压力测试得出了由于产量大导致绝对瓦斯涌出量大,相对量小的这类矿井直接法不能准确测出瓦斯压力,应该用间接法测得的结论。     

煤层瓦斯抽放的难易程度影响因数分析

煤的瓦斯含量直接影响煤层含瓦斯的多少和矿井瓦斯涌出量的大小,对于正确设计矿井通风,进行瓦斯抽放,以及生产矿井的正常通风瓦斯管理都有很大的意义。通过钻孔分析和测定煤层瓦斯压力、瓦斯含量、钻孔瓦斯流量及衰减系数和煤层透气性系数等几项指标来判定煤层瓦斯抽放的难易程度。因此煤层的各项瓦斯参数指标是指导矿井生产和科研工作的重要基础资料。     

科兴米山煤业瓦斯赋存规律与突出危险性预测

为揭示科兴米山煤业15#煤层瓦斯赋存规律,针对15#煤层瓦斯赋存特点及15111综采工作面开采条件,对米山煤业15#煤层的瓦斯参数进行了测试,编绘了15#煤层瓦斯含量分布预测图,揭示了其瓦斯赋存规律;采用分源预测法预测了矿井的瓦斯涌出量,并对煤与瓦斯区域突出危险性进行了预测。     

瓦斯含量直接测定与K1-P关系研究

本文通过实践摸索采用直接测定煤层瓦斯含量的方法快速准确的测定出煤层瓦斯含量，然后分析煤层瓦斯含量与压力、突出敏感指标之间的相互关系，为同类型煤与瓦斯突出矿井瓦斯综合治理提供了参考依据。     

肖家洼矿井8煤层瓦斯地质特征研究

煤层瓦斯含量是计算瓦斯涌出量的基础，同时也是预测煤与瓦斯突出的重要参数之一。本次对肖家洼矿井8煤层瓦斯赋存情况进行分析，分析影响煤层瓦斯赋存的主要因素。结果表明：煤层埋深是影响瓦斯赋存的主要因素，在生产过程中随着开采深度的增加，应加强对瓦斯数据的监测，并相应做好防治措施，确保矿井高效安全开采。     

隧道工程穿煤层安全技术研究

隧道施工过程中经常遇到含瓦斯煤层。瓦斯是煤的伴生气体,瓦斯含量与瓦斯压力共同决定了煤层瓦斯的赋存状态。在施工过程中,必须采取合理、有效的安全技术降低前方煤体瓦斯含量,抑制瓦斯涌出强度,确保巷道瓦斯浓度符合规定要求。本文从煤层瓦斯突出机理、瓦斯治理安全技术措施、施工工艺等方面进行了研究,保障隧道工程穿越煤层时人员安全。     

平顶山矿区己组不同破坏程度煤的瓦斯放散动力试验研究

本文针对平顶山矿区己组煤层不同破坏程度煤进行了瓦斯放散动力试验,试验结果表明,在相同吸附平衡压力条件下,煤的破坏程度越高,初始阶段相同时间内瓦斯解吸总量越大;在不同吸附平衡压力条件下,吸附平衡压力越高,初始阶段相同时间内瓦斯解吸总量越大：煤的破坏程度越高,瓦斯放散速度越快,相应曲线斜率越大。并研究确定了己组煤层钻屑瓦斯解吸指标K1与吸附平衡压力P的关系：K1=0．5342P^0.584,现场试验表明,确定的K1指标的临界值0.42ml／（g.min^0.5）能够满足安全生产需要。     

Choice in Currency in Iceland

An Icelandic post-graduate student at Oxford outlines a method of preventing inflation that could be applied in other countries.     

关于高职院校数学教学中开放题的有关问题初探

本文着重于讲解在高职院校数学教学中常出现的几种开放题,对它们的解法加以研究,归纳其一般思路、解法及其解答技巧,希望能有助于今后高职院校数学教学研究活动,供参考之用。     

Developments in human resource management in manufacturing in modern Britain

In this paper, developments in human resource management in manufacturing in modern Britain based on a national sample are examined. The organization and role of human resource management, employee involvement, training and development, work practices and rewards are all targeted for an assessment of current practices. This is a prelude for a contrast between manufacturing and non-manufacturing. The conclusion is that the similarities between manufacturing and non-manufacturing substantially outweigh the differences. By inference, too, developments in human resource management practices are likely to reflect changes in the broader environment of businesses (and differences between companies) rather than being specific to the main industrial sectors.     

Explaining Inter-Provincial Inequality in Productivity Growth in Crop Production in Pakistan

Abstract

Data on crop production are assembled for four provinces—Punjab, Sindh, North-West Frontier Province and Balochistan—for the period from 1980/81 to 2005/06 to examine inter-provincial differences in productivity growth rates. Propositions are put forward and examined to explain the superior productivity performance of Punjabi crop producers over those in Sindh and North-West Frontier Province, and the unusual productivity trends in Balochistan. The major factors relate to economic infrastructure and human capital. The impact of agricultural research is difficult to discern, and further work is required to assess the lagged effects of research expenditures on TFP growth.

Explication des déséquilibres interprovinciaux dans l'augmentation de la productivité dans la production de cultures au Pakistan

RÉSUMÉ On a rassemblé des données pour les quatre provinces suivantes: Penjab, Sindh, Khyber-Pakhtunkhwa, et Baloutchistan, pour la période 1980/81 à 2005/06, afin d'examiner les différences interprovinciales dans les taux d'expansion de la productivité. On présente et on examine des hypothèses pour expliquer le rendement supérieur des producteurs du Penjab par rapport à ceux du Sindh et du Khyber-Pakhtunkhwa, ainsi que les tendances de productivité inhabituelles du Baloutchistan. Les principaux facteurs se rapportent à l'infrastructure économique et au capital humain. L'impact de la recherche sur l'agriculture est difficile à établir, et des travaux supplémentaires seront nécessaires pour évaluer les effets décalés des frais de recherche sur l'expansion du TFP.

Explicación de la desigualdad inter-provincial en el crecimiento de la productividad de la producción de cultivos en Pakistán

EXTRACTO Se recopilan datos sobre la producción de cultivos de cuatro provincias: Punjab, Sindh, Provincia de la Frontera Norte-Oeste y Balochistan, durante el período de 1980/81 a 2005/06, para examinar las diferencias inter-provinciales en los índices de crecimiento de la productividad. Se plantean y examinan propuestas para explicar el mayor rendimiento de la productividad de los productores de cultivos Punjabi con respecto a los de Sindh y la Provincia de la Frontera Norte-Oeste, y las inusuales tendencias de la productividad de Balochistan. Los factores principales se relacionan con la infraestructura económica y el capital humano. El impacto de la investigación agrícola es difícil de discernir, y se requiere más trabajo para evaluar los efectos retrasados de los gastos de investigación en el crecimiento TFP.      

西部外贸中小企业发展的战略选择

中小企业是西部地区外贸进出口的重要力量。据统计，2005年，西部地区中小企业的进出口额达156．03亿美元，占西部地区进出口总额的34．6％，同比增长37．5％，表现出强劲的发展势头，成为推动西部地区对外贸易发展的一支最具活力的力量。然而，与东部地区同类企业发展相比，由于受区域经济发展水平、思想观念、经营环境以及政策等多种因素的影响和制约，西部外贸中小企业的发展还明显滞后。     

Trends in multiculturalism in health care

Materiel managers are faced with a shrinking world and changing work environment. The needs and expectations of the customer have shifted because of the increasing number of multicultural groups. These groups will continue to assert their right to culturally sensitive care. Materiel managers also need to learn to support and enhance the skills of a multicultural work force. One important tool for change will be technology. However, technology that brings the world closer together also creates new challenges for managers, who will have to deal with multicultural colleagues, buyers, sellers, and manufacturers of goods and services.     

Errors in variables in panel data

Panel data based studies in econometrics use the analysis of covariance approach to control for various ‘individual effects’ by estimating coefficients from the ‘within’ dimension of the data. Often, however, the results are unsatisfactory, with ‘too low’ and insignificant coefficients. Errors of measurement in the independent variables whose relative importance gets magnified in the within dimension are then blamed for this outcome.Errors-in-variables models have not been used widely, in part because they seem to require extraneous information to be identified. We show how a variety of errors-in-variables models may be identifiable and estimable in panel data without the use of external instruments and apply it to a relatively simple but not uninteresting case: the estimation of ‘labor demand’ relationships, also known as the ‘short-run increasing returns to scale’ puzzle.     

Mediation in industrial disputes in Britain

This article presents an overview of mediation in industrial disputes, and examines the British experience of using this form of third-party intervention since the establishment of the Advisory, Conciliation and Arbitration Service in 1974. The Author concludes that there is scope for the development of mediation in dealing with particular types of industrial disputes.     

我国审计的未来展望

我国审计未来的格局将会由现行的国家审计、内部审计和社会审计"三足鼎立"的局面转变为社会审计"一支独大"、其他两种审计模式趋弱的局面;审计的重心将是舞弊审计、绩效审计、环境审计和财务审计;国家审计、内部审计和社会审计的行为主体模式将分别是立法型、审计委员会负责型和民间型.