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The idea and project of the “Medium-Scale Experiment Field for Earthquake Prediction”──Research on observations and applications of mining earthquake in Mentougou Coal Mine
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作者 张少泉 任振启 +2 位作者 张连城 张建军 邹立晔 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第4期142-146,148-150+152-,共10页
A brief account of the development of the research on mining earthquakes and the general situation of the Mentougou Coal Mine medium scale experiment field for earthquake prediction and the project of monitor and p... A brief account of the development of the research on mining earthquakes and the general situation of the Mentougou Coal Mine medium scale experiment field for earthquake prediction and the project of monitor and prediction is given. The differences of waveforms between mining earthquakes and natural earthquakes is discussed. The magnitude frequency distribution of the 79 000 mining earthquakes of over M L1.0 from 1984 to 1995 is summarized . Finally, taking PH and PV, the principal compressive stress components of the focal mechanism of the mining earthquakes, as the criteria, analyses the stress background of the 12 large mining earthquakes. 展开更多
关键词 mining earthquakes mining seismology earthquake prediction Mentougou Coal Mine medium scale experiment field for earthquake prediction.
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Barriers to the Growth of Small and Medium Scale Construction Enterprises in Ghana
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作者 Simon Ofori Ametepey Emmanuel Yaw Frempong Jnr John Edward Cobbina 《Open Journal of Civil Engineering》 2022年第1期38-55,共18页
The construction industry in most developing economies is dominated heavily by small and medium scale enterprises. These construction enterprises need to thrive in an extremely competitive business environment. Conver... The construction industry in most developing economies is dominated heavily by small and medium scale enterprises. These construction enterprises need to thrive in an extremely competitive business environment. Conversely, most of these small and medium scale construction enterprises (SMSCE) are fraught with a plethora of barriers that inhibit and threaten their growth and survival. This research sought to evaluate the critical barriers that affect the growth of SMSCEs in the Ghanaian Construction Industry. The quantitative research method was adopted using a structured questionnaire with variables that were identified through a comprehensive literature review. The survey questionnaire was administered to 400 respondents comprising 250 SMSCEs, 100 Local Authority Engineers, and 50 Consultants to elicit data based on the identified variables. The major findings established by the study as barriers to the growth of SMSCEs in Ghana are largely structured as financial/fiscal barriers, business development barriers, technical/technological barriers, corruption barriers, knowledge management barriers, project acquisition barriers. A guiding framework should be developed based on the barriers identified to aid the growth and survival of SMSCEs in Ghana. 展开更多
关键词 Barriers Business Growth Business Survival Developing Countries Small and medium scale Enterprise SME
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An automated medium scale prototype for anaerobic co-digestion of olive mill wastewater 被引量:1
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作者 B.Bernardi S.Benalia +2 位作者 D.A.Zema V.Tamburino G.Zimbalatti 《Information Processing in Agriculture》 EI 2017年第4期316-320,共5页
Olive oil production constitutes one of the most important agro-industrial business for Mediterranean countries,where 97% of the international production is focused.Such an activity,mainly carried out through three ph... Olive oil production constitutes one of the most important agro-industrial business for Mediterranean countries,where 97% of the international production is focused.Such an activity,mainly carried out through three phase olive oil mill plants,generates huge amounts of solid and liquid by-products further than olive oil.Physico-chemical features of these by-products depend on various factors such as soil and climatic conditions,agricultural practices and processing.As currently carried out,the disposal of these byproducts may lead to numerous problems taking into account management,economic and particularly environmental aspects.Indeed,olive mill wastewater is not easily biodegradable due to its high chemical and biochemical oxygen demand,its high content in phenolic compounds,high ratio C/N and low pH,leading consequently to soil and water source pollution.Considering,the above-mentioned statements,olive mill waste disposal constitutes nowadays a challenge for oil industry stakeholders.It becomes necessary to look for alternative solutions in order to overcome environmental problems and ensure the sustainability of oil industry.Anaerobic co-digestion of olive mill wastewater with other agro-industrial matrices could be one of these solutions;since it offers the possibility to produce green energy and break down toxicological compounds contained in these wastewater for a better disposal of the digested matrices as soil conditioner.In this contest,this note reports the functioning principle of an automated medium scale plant for anaerobic co-digestion of olive mill wastewater. 展开更多
关键词 medium scale prototype Olive mill wastewater(OMWW) Anaerobic co-digestion(AcoD) Automatic process
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改善中型轧机滚动轴承承载特性的设计与实现
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作者 李明 申光宪 孙利娜 《机械科学与技术》 CSCD 北大核心 2010年第9期1205-1208,共4页
将轧机微尺度理论用于600中型轧机胶木瓦轴承辊系的滚动轴承化,研制了具有空间自位静定特性和分力支座机构的滚动轴承辊系,确保轧机空载和重载不同工况下的静定条件,提高轴承承载能力,延长滚动轴承的工作寿命。辊系轧制生产运行正常,所... 将轧机微尺度理论用于600中型轧机胶木瓦轴承辊系的滚动轴承化,研制了具有空间自位静定特性和分力支座机构的滚动轴承辊系,确保轧机空载和重载不同工况下的静定条件,提高轴承承载能力,延长滚动轴承的工作寿命。辊系轧制生产运行正常,所使用的国产滚动轴承已超过额定寿命,实现了轧机设计的长寿运行目标。 展开更多
关键词 中型轧机 滚动轴承 微尺度理论 空间自位静定特性 分力支座
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热轧中宽带钢氧化铁皮产生原因及解决措施 被引量:5
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作者 华维 张洪涛 +2 位作者 刘佳 张海丰 王小龙 《河北冶金》 2008年第2期31-33,30,共4页
分析了唐山建龙热轧中宽带钢氧化铁皮的产生原因,通过对加热温度、轧制工艺以及除鳞设备的优化,减少了氧化铁皮的发生率,取得了较好效果。
关键词 热轧 中宽带钢 氧化铁皮 产生原因 解决措施
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中速磨煤机在大型煤粉电站锅炉应用现状研究 被引量:6
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作者 刘家利 屠竞毅 +2 位作者 方顺利 姚伟 郭洋州 《热力发电》 CAS CSCD 北大核心 2021年第3期19-26,共8页
为了确保新建火电机组的制粉系统能够满足机组带负荷能力和调峰能力,并从制粉系统侧提供满足燃烧需要的煤粉细度,本文根据大量已投运机组的中速磨煤机性能考核结果,对中速磨煤机的理论计算研磨出力和实际研磨出力进行了研究分析。结果表... 为了确保新建火电机组的制粉系统能够满足机组带负荷能力和调峰能力,并从制粉系统侧提供满足燃烧需要的煤粉细度,本文根据大量已投运机组的中速磨煤机性能考核结果,对中速磨煤机的理论计算研磨出力和实际研磨出力进行了研究分析。结果表明:目前大多数机组的中速磨煤机实际达不到设计值,部分机组的煤粉细度和粒度均匀性也达不到设计值,表明了仅依赖目前常用的通过理论计算进行磨煤机选型有一定风险;推荐新机组根据设计煤和校核煤在同类型磨煤机上的现场试磨结果进行磨煤机型号选取,具体磨煤机型号选取还需综合考虑机组带负荷能力和调峰能力要求,以免磨煤机型号选取过大或者选取过小造成调峰能力和带负荷能力差。本研究成果可为大型煤粉锅炉的中速磨煤机选型以及在役机组的煤种掺烧或煤种变更提供参考。 展开更多
关键词 大型电站 煤粉锅炉 中速磨煤机 磨煤机出力 带负荷能力 调峰能力
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Access to Credit by SMEs and Implications for Economic Growth in Nigeria
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作者 Afolabi Babatunde Ekpenyong Keziah Yemisi +1 位作者 Akomolafe John Awoyemi Olanike Bosede 《Chinese Business Review》 2016年第12期591-600,共10页
The purpose of this study is to examine the impact of credit availability to SMEs on the economic growth in Nigeria. The study period was from 1981 to 2012. Vector autoregressive model was employed to avoid the proble... The purpose of this study is to examine the impact of credit availability to SMEs on the economic growth in Nigeria. The study period was from 1981 to 2012. Vector autoregressive model was employed to avoid the problem of endogenity. The results show that though inflation has a negative effect on SMEs fmancing, it still significantly influences economic growth. This paper therefore concludes that there is a need for government to intensify efforts to increase SMEs financing in the country through the introduction of a special intervention fund for SMEs. 展开更多
关键词 small and medium scale enterprises SMEs fmancing economic growth NIGERIA commercial banks
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降低大型半自磨机磨矿介质单耗试验研究与应用
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作者 王英姿 《矿业工程》 CAS 2015年第6期21-23,共3页
针对袁家村铁矿矿石硬度高、半自磨机直径大的特点,通过优化磨矿介质材质以及加球方法,在保证磨机生产能力不变的前提下,降低介质单耗与磨矿电耗,达到缩减选矿生产成本的目的。
关键词 大型半自磨机 磨矿机理 磨矿介质 试验研究
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中厚板轧机微尺度静定化升级 被引量:2
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作者 申光宪 郑永江 +1 位作者 王涛 黄庆学 《轧钢》 2019年第1期9-15,共7页
中厚板轧机常因受到事故干扰而不能实现其高端轧制能力,其关键在于约0.3mm的轧辊弯曲挠度和轧辊轴承座侧面与机架窗口立柱之间约1mm间隙两个微尺度量的负面影响。依据机构学微尺度静定设计理论对中厚板轧机的微尺度静定化进行升级。辊... 中厚板轧机常因受到事故干扰而不能实现其高端轧制能力,其关键在于约0.3mm的轧辊弯曲挠度和轧辊轴承座侧面与机架窗口立柱之间约1mm间隙两个微尺度量的负面影响。依据机构学微尺度静定设计理论对中厚板轧机的微尺度静定化进行升级。辊系机构静定化设计包括取消原偏移距设置并采用智能衬板以实现轧制过程中四辊平行,防止四列短圆柱滚动轴承烧损、轧机颤振、板带镰刀弯和辊系叼板窜辊等弊端的同时还提高了轧机固有频率。中厚板轧机的机构学静定化升级,可充分释放轧机高端能力,实现大压下轧制新工艺并可生产高强度新品种板带,达到降本增效的目的。 展开更多
关键词 中厚板轧机 微尺度参量 机构学静定化 高端轧制能力
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