煤层瓦斯抽放封孔工艺研究与应用

针对突出煤层瓦斯抽采钻孔封孔现场存在的技术难题,以钻孔封孔技术理论为指导。以天荣一矿为研究背景,比较和研究了几种常见的封孔工艺,在井下现场实施过程中,进一步优化了封孔施工工艺。研究结果表明:保证了封孔质量,有效提高了瓦斯抽放浓度。     

囊袋式两端自堵封孔工艺实验效果研究——以焦煤集团中马村矿为例

抽采钻孔封孔质量的优劣直接影响着煤矿回采工作面瓦斯抽采效果。针对国内瓦斯抽采浓度普遍偏低的现状,特引进囊袋式两端自堵封孔工艺以提高瓦斯抽采功效及浓度。本文以焦煤集团中马村矿为例,通过实验探索该工艺在增强瓦斯抽采效果上的优势。     

马丽散F封孔胶在提高瓦斯抽采效果中的应用

文章主要结合大湾煤矿的实际情况,对瓦斯抽采的具体施工技术展开了探讨,并在此基础上重点对马丽散F封孔胶在提高瓦斯抽采效果中的应用进行了分析,给出了施工工艺及应用对比效果,对于进一步提高马丽散F封孔胶在瓦斯抽采中的应用及提高矿井生产的安全水平,推进瓦斯治理工作,构建本质安全型矿井具有一定的借鉴意义。     

本煤层抽放钻孔封孔技术研究与实施

通过研究及实践,指出采用新型本煤层钻孔封孔技术来解决使用传统方法存在的抽采浓度低、抽采量小、衰减快、微风自燃、瓦斯利用率低等问题。使用该项新技术可有效提高封孔成功率,抽放效果好,具有显著的推广应用价值。     

采动影响下穿层钻孔二次封孔技术研究

基于对某煤矿煤层瓦斯赋存情况的总结,分析了其底板瓦斯抽采巷抽采钻孔设计方案及封孔工艺流程,指出采动影响是造成巷道松动圈扩大、钻孔漏气、瓦斯浓度过低的主要原因,根据其瓦斯抽采过程中存在的实际问题,研究设计出一种新型封孔管技术方案,并进行了工业性实验,结果表明,在采动影响下应用新型瓦斯抽采封孔技术,可达到大幅度提高瓦斯浓度、提高瓦斯抽采率的目的。     

水泥砂浆封孔工艺改进

水泥砂浆封孔工艺在瓦斯抽采钻孔封孔上广泛应用，但其现场操作各有不同。本文介绍的此种水泥砂浆增压封孔工艺是一种既简单、经济，又行之有效的封孔方式。     

水泥砂浆封孔工艺改进

水泥砂浆封孔工艺在瓦斯抽采钻孔封孔上广泛应用，但其现场操作各有不同。本文介绍的此种水泥砂浆增压封孔工艺是一种既简单、经济，又行之有效的封孔方式。     

关于利用新工艺封孔以提高钻孔抽放质量的探究

瓦斯抽采工艺是一项十分严密、细致的工作。其工艺的好坏直接关系到经济效益和安全问题。本文针对瓦斯抽采过程中封孔技术进行分析研究,积极探讨新工艺,一期提高煤矿瓦斯抽采质量。     

突出煤层立体交叉钻孔抽采瓦斯技术研究

为彻底解决穿岩孔与顺槽本煤层交叉布置后瓦斯抽放问题,提高钻孔浓度,延长钻孔抽放时间,实现区域抽放区域防突的目的,并为同类矿井在类似条件下提高抽放效率提供理论基础和可借鉴的经验。鹤煤十矿进行了＂突出煤层立体交叉钻孔抽采瓦斯技术研究＂科技项目攻关,实践表明对底板抽放巷穿层钻孔及顺层钻孔两种钻孔进行科学合理的布置、改进钻孔封孔技术和相关配套技术,达到钻孔覆盖范围更加科学合理、摸索出一套穿岩钻孔与顺槽本煤层钻孔立体交叉布置瓦斯抽放技术及相关配套工艺,达到了提高瓦斯抽放效率得到有效提高的目的。     

突出煤层立体交叉钻孔抽采瓦斯技术研究

为彻底解决穿岩孔与顺槽本煤层交叉布置后瓦斯抽放问题,提高钻孔浓度,延长钻孔抽放时间,实现区域抽放区域防突的目的,并为同类矿井在类似条件下提高抽放效率提供理论基础和可借鉴的经验。鹤煤十矿进行了"突出煤层立体交叉钻孔抽采瓦斯技术研究"科技项目攻关,实践表明对底板抽放巷穿层钻孔及顺层钻孔两种钻孔进行科学合理的布置、改进钻孔封孔技术和相关配套技术,达到钻孔覆盖范围更加科学合理、摸索出一套穿岩钻孔与顺槽本煤层钻孔立体交叉布置瓦斯抽放技术及相关配套工艺,达到了提高瓦斯抽放效率得到有效提高的目的。     

Agglomeration,Agriculture, and the Perspective of the Periphery

Abstract

This paper aims at pulling everything related to ‘agriculture’ or the ‘periphery’ a little more into the focus of research. We try to achieve this through surveying the existing theoretical and empirical literature in the field of NEG (New Economic Geography) in order to elaborate its linkages to immobile factors such as land, land-intensive productive activities, agriculture, rural areas, and the periphery. The main features of the broad variety of NEG models are reviewed with a special focus on the theme of agglomeration, which turns out to be vital for rural areas. All of these contributions are then commented on, with the aim of suggesting and discussing some future lines of research in the field.

Agglomération, agriculture, et la perspective de la périphérie

RÉSUMÉ La présente communication s'efforce de placer davantage tout ce qui concerne ‘l'agriculture’ ou la ‘périphérie’ sous l'optique de la recherche. Pour ceci, nous nous efforçons d'examiner de près les ouvrages théoriques et empiriques existants dans le domaine du NEG (New Economic Geography), afin d'en examiner les rapports avec des facteurs immuables comme la terre, les activités de production à utilisation intensive de la terre, l'agriculture, les zones rurales, et la périphérie. On se penche sur les principales caractéristiques du grand nombre de modèles NEG, en mettant tout particulièrement l'accent sur le thème de l'agglomération, qui s'avère jouer un rôle d'importance primordiale pour les zones rurales. On présente ensuite des commentaires sur toutes ces contributions dans le but de proposer certaines filières de recherche futures dans ce domaine, et d'en discuter.

Aglomeración, agricultura y la perspectiva de la periferia

RÉSUMÉ Este trabajo tiene como objetivo poner todo lo relacionado con la ‘agricultura’ o la ‘periferia’ un poco más en el foco de investigación. Intentamos hacerlo a través de una inspección de la bibliografía teórica y empírica existente en el campo NEG (New Economic Geography), con objeto de elaborar sus vínculos con factores inmóviles, tales como el terreno, actividades productivas que requieren terreno, agricultura, áreas rurales y la periferia. Las principales características de la amplia variedad de modelos NEG se revisan con un enfoque especial en el tema de la aglomeración, que resulta tener una importancia vital para las áreas rurales. Seguidamente, todas estas contribuciones se comentan con el propósito de sugerir y discutir líneas futuras de investigación en el campo.

     

那些人 那些事 那个年代

“一九六零年四月十六号下午三点之前的一分钟你和我在一起,因为你我会记住这一分钟。从现在开始我们就是一分钟的朋友,这是事实,你改变不了,因为已经过去了。”——《阿飞正传》     

Property rights,transaction costs,and the limits of the market

Economics of Governance - To clarify the determinants and interaction of property rights and transaction costs, I study the design of the property rights on either a good whose consensual transfer...     

Graft, Bribes, and the Practice of Corruption

We construct a dynamic model of corruption in organizations where officials privately know their propensity for corruption and clients optimally choose the bribe offered. We show that there is a continuum set of stationary bribe equilibria due exclusively to the dynamic nature of the model and the endogenous determination of bribes. This can explain why similar countries have stable but different "implicit prices" for the same illegal services. We also show that, by not considering the reaction of clients, traditional analysis have systematically overestimated the beneficial effect of increasing wages as an anticorruption measure.     

Congestion,agglomeration, and the structure of cities

Congestion costs in urban areas are significant and clearly represent a negative externality. Nonetheless, economists also recognize the production advantages of urban density in the form of positive agglomeration externalities. The long-run equilibrium outcomes in economies with multiple correlated but offsetting externalities have yet to be fully explored in the literature. Therefore, I develop a spatial equilibrium model of urban structure that includes both congestion costs and agglomeration externalities. I then estimate the structural parameters of the model using a computational algorithm to match the spatial distribution of employment, population, land use, land rents, and commute times in the data. Policy simulations based on the estimates suggest that congestion pricing may have ambiguous consequences for economic welfare.     

Power,Subsidiarity, and the Economy of Exclusion

According to Pope Francis, an “economy of exclusion” is an economy with barriers that prevent individuals and groups from participating in the economy and society to their full potential. Power is a key determinant for both exclusion and inclusion. All economies are based on power relations and an “economy of exclusion” is an abuse of power. This contribution looks at what economic power is and how it can build barriers of exclusion or pathways to inclusion. We use income inequality as a measure of exclusion, giving a general history of power and inequality to demonstrate the role of power. Lastly, we look at the concept of subsidiarity in Catholic social thought as a principle to guide the use of power in the economy.     

Malthus,Darwin, and the Descent of Economics

Confusion about overpopulation stems from the writings of Thomas Malthus in 1798. It was compounded by Charles Darwin and Alfred Russel Wallace, both of whom made the Malthusian “struggle for existence” the basis of natural selection in the evolutionary process. Malthus argued, without evidence, that human population growth will continue unchecked until regulated by external factors such as hunger and disease. Darwin and Wallace cemented that idea into evolutionary theory. Recent evolutionary biologists have focused on gene frequency as a way to compare the reproductive success of one individual against another within the same species. However, among humans, the true basis of reproductive success is grounded in control of the resources necessary for survival. Humans sometimes adapt to environmental stress by having more children, not fewer, which means that poverty can cause population growth, not the reverse. Recognizing this simple relationship would have helped Darwin resolve a dilemma at the heart of his theory: his expectation that the most successful members of our species would have the most children, an idea contradicted by his observation of large, poor families among the Irish. The evolutionary puzzle can be solved by observing that providing equal access to land enables humans to limit their own fertility. The problem of equal access can be addressed by implementing Henry George's idea of taxing the value of land, thereby preventing hoarding and gross inequality of wealth.