评矿井瓦斯测定

近十年来,测定矿井瓦斯的工作有了重大发展。最明显的是各种矿井瓦斯测定仪表的使用数量大大增加。并且仪表的性能种类也相应得到发展。目前已广泛研究和生产了一系列矿井瓦斯测定仪表,特別是生产了能连续测定瓦斯的仪器,从而为矿井将来予防瓦斯威胁提供了一个完整的防护系统。     

井上、下气压监测对测定矿井通风阻力的影响

1 引言 生产矿井要定期对全矿进行通风阻力测定，以达到科学管理矿井的目的。长期以来，通风阻力测定往往精度不高，误差过大。影响阻力测定精度的因素很多，其中用“基点法”进行通风阻力测定时地面大气压的变化是影响其精度的一个重要因素，这就要求在阻力测定时必须进行气压……     

热敏式风表风速测量参数优化

为提高矿井风速测量中设备测量精度,应用自行设计的风速测定校正系统,测试出不同风速准确值及热敏风表读数值,同时应用回归分析的方式得出热敏风表测量值与风速准确值间的关系,确定风表读数的修正参数,并进一步对修正参数进行试验验证,试验结果显示该修正参数可有效提高风速测定精度。     

矿井通风阻力的测定精度及其计算

<正> 对工程的计算和测定都有一定的精度要求,精度要求必须合理,如果精度要求过高,经过努力达不到,将造成浪费;精度过低,使用起来将产生错误。几年来,对几个矿井进行了全矿井的阻力测定,共测定巷道118821m,测得基础数据6327个。在实际测定中体会到,矿井通风系统阻力测定也应根据我国目前实际情况(仪器设备、技术力量     

用Excel实现矿井风网动态管理

在微软公司Ｅｘｃｅｌ软件基础上二次开发出矿井风网参数处理系统，处理矿井通风阻力测定的数据，自动计算出结果，将我和测定数据转换为矿井风网数据，具有风网数据的修改、删除、查询、转储等功能，实现了风网的动态管理。     

中国煤矿安全监测仪表的发展

重点介绍了目前中国煤矿便携式瓦斯仪表和固定式瓦斯遥测报警仪以及多参数矿井环境监测系统的发展情况和研究动向。     

井上下气压监测对通风阻力测定影响的优劣分析

《煤矿安全规程》规定，所有的生产矿井都要定期对全矿进行通风阻力测定，但是，通风阻力测定往往精度不高，影响阻力测定精度的因素很多，其中地面大气压的变化是在用“基点法”进行通风阻力测定时影响其精度的一个重要因素，这就要求在阻力测定时必须进行气压校对。本文讨论的是在气压监测时气压计设置的位置。……     

自行研制矿井通风监测系统

矿井通风机的运行状况直接关系着矿井的安全生产，我矿对 通风机的监测仪表布置分散，有的还须手工操作，程序复杂可靠性差，手段落后。因此，我们采用计算机和网络技术开发了一套集中监测系统，可对通风机及通风系统进行实时监测，不但可即时显示、存储各项参数，还可按调度中心的指令发送数据，以便随时掌握通风系统的工作状况保证矿井的安全生产。 １ 系统的功能及技术指标 本系统是采用单片机技术及集成电路组成的小型专用监测系统，它可以对矿井主回风巷的风速、负压及通风机的轴温、风机电流和电压等参数进行实时集中监侧，用ＬＥＤ显…     

矿井通风阻力测定数据处理基础理论研究及其软件开发

在研究压差计法、气压计基点法和气压计双测点法3种常用矿井通风阻力测定方法及其数据处理原理的基础上,以VB程序语言和Microsoft Access数据库管理软件为平台,开发了矿井通风阻力测定数据处理软件。该软件具有:录入与维护原始数据,识别和剔除不合理数据;分步计算测点参数、测段阻力和矿井总阻力等;进行精度分析与误差校正、并联风路检验和阻力测定报告的直接输出等多种功能。该软件能够大大降低人为误差,提高工作效率,并已在淮南某矿、平顶山某矿等矿井阻力测定数据处理的应用中得到初步应用。     

方庄煤矿新井通风阻力测定与分析

采用精密气压计两点同时测量法测定方庄煤矿新井通风阻力，介绍了测点的布置原则，并进行了阻力精度评价，分析了矿井通风系统阻力状况，指出了通风系统中存在的问题，为矿井通风管理提供了可靠依据。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

唐口煤矿深部复杂开采工作面瓦斯分源涌出规律研究

研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m³/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。