太原市大气污染形成原因初探

利用1971-2002年气象资料及近几年大气污染数据，分析了太原市空气污染现状及其形成原因。总体来讲，太原市近几年空气质量有所好转；TSP（或PM10）为太原市首要污染物；冬半年（尤其是采暖期）空气质量明显下降；大气的稳定性、风、降水情况、雾等是影响空气污染物扩散的主要气象因素。     

廊坊市SO2污染及相关气象条件

本文选用2003年1月1日-2007年12月31日廊坊市环境检测站资料和同期气象观测资料,系统地分析了廊坊市SO₂污染平均浓度和不同等级的逐月变化、季节变化、年变化、采暖期和非采暖期平均浓度的差异,以及SO₂作为首要污染物的特征。详细讨论了SO₂平均浓度与地面常规气象要素的相关性。     

地下装载机司机能见度相关问题简介

简介了地下装载机的司机能见度及其评定方法,以某8m3带驾驶室的地下装载机司机室能见度测试方法和测试视线图为例进行了说明,并分析了地下装载机能见度的影响因素及改进方法。     

廊坊市大气污染物浓度变化特征及影响因素分析

针对廊坊市空气污染问题日益严重、雾霾污染范围持续扩大的现状,调查了廊坊市PM2.5和臭氧污染情况及其影响因素,基于空间自相关理论构建了空间计量模型,收集了廊坊市2020年大气污染物浓度变化特征的相关数据,对数据进行了处理分析。研究结果表明,2020年6月、12月的PM2.5平均浓度分别达到最低、最高水平,为69.6 μg/m³和154.3 μg/m³;2020年12月、6月的臭氧平均浓度分别达到最低、最高水平,为63.2 μg/m³和104.31 μg/m³。PM2.5的污染和臭氧污染空间自相关性明显,存在空间区域集聚现象。年均风速以及年均气温对PM2.5的污染存在负向影响,臭氧污染存在正向影响;年相对湿度对PM2.5存在正向影响,对臭氧污染存在负向影响。研究可为后续廊坊市PM2.5以及臭氧污染治理提供有效的数据参考。     

矿井胶带火灾模拟与逃生影响因素分析研究

矿井实际生产过程中,胶带火灾受多种因素影响,为确定矿井胶带火灾真实燃烧特性及人员逃生影响因素,本文应用火灾动力模拟软件PyroSim模拟了申家庄矿发生胶带火灾时,巷道内温度、烟气浓度及能见度随时间的变化情况,分析得出矿井胶带火灾时影响人员逃生的主要因素是烟气温度、CO浓度以及能见度。模拟结果表明该矿胶带火灾发生后的前200s是火源下风侧人员顺利逃生的关键时期,400s后巷道高温烟气、高浓度CO以及低能见度就严重影响人员逃生。研究结果为矿井应急救援和火灾逃生提供了参考。     

不同所有制煤炭企业经济效益的比较研究

本文首先建立了一套评价煤炭企业经济效益的指标体系,然后应用改进的熵权法,比较研究了不同所有制煤炭企业的经济效益水平.通过实证研究发现,2005年的煤炭企业的经济效益好于2006年,从中反映了国家宏观调控对整个煤炭行业有很大影响.研究进一步表明,私营企业、集体企业以及股份合作企业的经济效益,在各类所有制煤炭企业表现最好,而外资与国有煤炭企业的经济效益水平最差,其中外资受到宏观调控的影响最大.     

助磨剂对绢云母超细粉碎的影响

研究了 3种助磨剂 (硅酸钠、柠檬酸钠、三聚磷酸钠 )对绢云母超细粉碎助磨效果的影响。其中三聚磷酸钠的效果最好 ,硅酸钠的效果最差 ;同时还发现助磨剂三聚磷酸钠在 0 .2 0 %、且磨矿浓度在 40 %左右时助磨效能最好     

不同坡面形态滑坡的稳定性分析

为了研究坡面形态对滑坡稳定性的影响,设计3种坡度、2种坡高共6组试验,对不同坡面形态的滑坡进行了物理模拟试验,通过抬升试验模型槽模拟滑坡失稳破坏的过程,记录破坏过程和破坏时的临界破坏角度,分析了不同坡型滑坡的稳定性和破坏情况。试验结果表明,相同坡度、相同坡高的情况下,凸坡所需抬升角度最低,其稳定性最差,凹坡最高,其稳定性最好,且凸坡破坏时更易发生分级启动。从滑坡表面角度和滑体重量进行理论分析,对试验结果进行解释。采用稳定性计算获得不同坡度下不同坡面形态滑坡的稳定性系数,结果为凸坡稳定性系数最低,凹坡稳定性系数最高,计算结果与试验结果相同,由此可得在坡度、坡高、纵曲率均相同的条件下,凸坡稳定性最差,直线型坡次之,凹坡稳定性最好。     

莺山凹陷沙河子组砂砾岩储层控制因素分析

莺山凹陷沙河子组资源潜力大,是松辽盆地深层的重要勘探领域。以往沙河子组储层研究相对较少,储层控制因素不清楚,制约了勘探部署。通过系统分析沙河子组储层与岩性、相带、埋深的关系,探讨了储层发育的控制因素,研究认为:砂岩物性最好,砂砾岩次之,粉砂岩最差;物性随最大古埋深减小,储层深度下限为4500m;(扇)三角洲前缘物性最好,(扇)三角洲平原次之,滨浅湖最差,最大湖泛面附近储层物性较好。根据以上认识,提出了莺山凹陷沙河子组有利储集区带预测的原则。     

长江干流大渡口区段岸坡地质灾害发育特征分析

长江干流大渡口区段岸坡地质灾害以滑坡为主,主要受地质条件和气象因素控制。在收集滑坡勘察、试验以及隐患点排查的基础上,对长江干流大渡口区段岸坡地质灾害的空间、时间分布规律、稳定性现状及影响因素做了分析论述。     

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     

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     

2014 second batch of rare earth quota released

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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