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《有色冶金节能》2006,23(2):I0006-I0006
东北大学材料与冶金学院热能与环境工程研究所的前身是东北大学热能工程系,是辽宁省重点学科一热能工程学科建设的依托单位,设有”动力工程及工程热物理”一级学科博士后工作流动站.具有博士学位和硕士学位授予权。2001年.成立”东北大学工业生态学研究中心”;2002年.经国家环境保护总局批准.以热能与环境工程研究所为核心组建了“国家环境保护生态工业重点实验室”;2003年,经辽宁省教育厅批准成立“辽宁省生态工业重点实验室”:同年列入国家”985工程”科技创新平台建设项目。目前,有中国工程院院士2人,博士生导师4人,教授6人;副教授8人,讲师3人,助教3人,高级工程师1人,工程师2人。 相似文献
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矿山达到最大生产能力及完善技术改造之后,依靠地质资源不断开发与资本积累,应以本行业生产与技术优势扩张规模,增大科技投入,改变单一开采业为采选冶、黄金精炼、深加工和贸易、科研,即科工贸一体化的链条产业,提高综合经济效益,创出一条中国式矿山持续发展的道路。 相似文献
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随着改革开放的不断深入,国内一些知名企业通过不断的技术引与自主创新,拥有和掌握了大量的国内外先进技术。与此同时,由于认识上的偏颇,这些企业的管理水平却没有得到同步提升,而是一味翻版国外的管理模式,忽略了管理的地域特性,致使出现了很多“水土不服”现象,企业管理总处在一个相对“滞后”的状态。在这一背景下,吸收国外先进的管理理念,创造出适合自身特点的管理方式,增强企业的核心竞争力,已成为我们刻不容缓的任务。 相似文献
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1前言 精科是高炉炼铁的基础,炉料的合理搭配是获得良好的技术经济指标的保证。作为精料技术重大举措之一的鞍钢矿山系统提铁降硅工艺改造,为炼铁技术经济指标的改善提供了必要保障。但提铁降硅后,铁矿石含铁品位提高,SiO2含量降低,烧结原料条件发生了明显变化,致使烧结液相量减少,烧结矿质量不尽合理;加之铁精矿自身特性各不相同,其在烧结过程中的高温行为和作用亦有差别: 相似文献
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我国铅锌矿产资源丰富,但其自然禀赋差且矿物组成复杂,导致其综合回收利用难度大。甘肃洛坝铅锌矿是一座含铅锌且伴生有少量银、硫的泥岩—细碎屑岩型铅锌矿床,因其矿石性质复杂,较早期形成的矿石性质发生明显变化,导致铅锌分选指标及精矿质量下降。为解决现有选矿生产过程中存在的问题,寻找适宜的改进措施和方法,以提高铅锌资源综合利用效率,在研究矿石性质的基础上开展了详细的工艺流程考察。研究结果表明:矿石中碳质、硅质等脉石矿物含量升高,碎磨过程易于泥化,且吸附性能和可浮性好,这些是影响铅锌分选指标的主要因素;通过优化碎磨工艺参数,减少了碳质、硅质等脉石矿物的泥化程度;在浮选工艺中添加适宜抑制剂,并采用高选择性的铅、锌矿物捕收剂,可显著提高铅、锌精矿品位和质量,大幅提高铅、锌回收率,从而实现该复杂含碳低品位铅锌资源的高效综合回收,并为同类矿产资源的选矿回收提供参考依据。 相似文献
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MF Shuba 《Canadian Metallurgical Quarterly》1977,264(3):853-864
1. The ionic mechanism of the excitatory action of catecholamines and histamine on the smooth muscle cells of guinea-pig ureter was studied with the double sucrose-gap method. 2. In normal conditions adrenaline and noradrenaline in a concentration of 10(-5) g/ml., and histamine in a concentration of 10(-6) g/ml., prolonged the duration of the plateau of the action potential and increased the amplitude and duration of the phasic contraction. Sometimes these changes were accompanied by a slight depolarization of the muscle membrane and by a small increase (with noradrenaline) or decrease (with histamine) of the membrane resistance. The amplitude and duration of the fast spike component of the action potential were not changed. 3. Isoprenaline in a concentration of 10(-5) g/ml. either caused no change or it decreased the duration of the plateau, reduced the amplitude of contractions and reduced excitability. 4. Tetraethyl ammonium (TEA; 5 mM), which blocks the delayed outward K current, did not prevent the increase in the duration of the plateau nor the increase of the amplitude and duration of the contractions by noradrenaline and histamine. 5. In Na-free or in K-free solution or in the presence of ouabain, i.e. in conditions in which the Na-gradient across the membrane was reduced, noradrenaline and histamine were unable to increase the duration of the plateau and the amplitude and duration of the contraction. 6. In the presence of Mn2+ (2 mM) which suppressed the spike component of tha action potential and the phasic contraction, theeffects of noradrenaline and histamine were almost abolished. 7. The results suggest a dual ionic mechanism of the alpha-action of catecholamines and of the action of histamine on the smooth muscle of ureter: (1) these drugs affect the passive ionic permeability of the membrane in a manner that results in depolarization; (2) they specifically activate the potential-dependent conductance of the slow Na channels, thereby increasing the plateau duration. The increased amplitude and duration of the contraction is the result of their primary effect on the plateau of the action potential. 相似文献
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VI Kuvakin 《Canadian Metallurgical Quarterly》1998,319(4):4-13, 96
Scientific generalization of the medical units maintenance experience in wars and armed conflicts of the second half of the XX century and at occurrence and liquidation of consequences of the extreme situations in view of further development of the military--medical science, its differentiation and formation of new scientific disciplines and theories. Justified necessity for medical service management theory in a relatively independent branch of the military medical service--medical science. The distinctive attributes of the scientific discipline are indicated. The definitions and the structure of the object and the subject of the theory of management of the medical service are given, and new laws are formulated. The purpose, problem and contents of management of the medical service as educational discipline is determined. Some questions of coordination of its fundamental and applied parts are discussed. 相似文献
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ZHENG Ai- qin SONG Xin- li MA Yu- xi SUN Xin- jun JIA Juan LIANG Xiao- kai 《钢铁研究学报》2018,30(9):747-753
The effect of copper on the microstructure and strength and ductility of low alloy wear resistance steels without copper and copper bearing was studied. The CCT curve was calculated by JmatPro software. The microstructure was analyzed by OM and TEM and the mechanical properties and ductility were tested by universal tensile testing machine and impact testing machine. The results show that the element of copper increases the stability of austenite and the transformation of ferrite and pearlite is postponed for the copper bearing steel. The microstructure is composed of matensite and lower bainite for the experimental steels and the content of martensite of the steel bearing copper is higher than the steel without copper. There are nano- size precipitations of (Nb,Ti)C and (Nb,Ti,Mo)C in the matrix of the two steels. The yield strength and the impact energy at -60?? of the steel with 0. 49 mass% copper is higher than that of the steel without copper. The element of copper is benefit to improve strength and low temperature ductility for the low alloy resistant steel. 相似文献
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岩石与岩体内部结构、空间尺度及裂隙分布形式不同,在冻融循环作用下其损伤劣化机制存在显著差异,损伤评判标准亦有所不同,因此厘清岩石与岩体冻融损伤内涵区别并总结相关研究进展具有重要意义。在内涵方面,岩石损伤主要是内部微小缺陷作用,属于微观层面问题(毫米量级及以下尺度);而岩体损伤则更加关注节理裂隙的影响,属于宏观层面问题(厘米量级及以上尺度)。目前冻融损伤相关研究主要集中在完整岩石块体,对于含有宏观裂隙的岩体研究较少;岩石冻胀是原位水冻胀与迁移水冻胀共同作用的结果,主要从冻胀力与疲劳损伤2个角度进行岩石冻融损伤本构模型的构建研究。未来岩体冻融损伤研究应重点关注裂隙所带来的影响,即从微观尺度入手,利用室内试验探究冻融循环过程孔隙和裂隙内部水分迁移冻胀机制与相互作用规律,结合现场试验与数值模拟研究构建大尺度下岩体冻融损伤本构模型,最终形成寒区岩石与岩体冻融损伤评价体系。 相似文献
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采用真空感应熔炼+保护气氛电渣重熔+真空自耗重熔三联冶炼工艺制备的GH4169合金由于其合金化程度较高,且合金铸锭尺寸较大,元素偏析、成分分布不均造成的组织差异都会对合金的力学性能、物理性能产生有害影响。实验基于微束X射线荧光光谱(μ-XRF)具有微区高分辨率、分析速度快、多元素同步分析、非破坏性等优点,通过优化测定条件以及仪器定量方法,建立了基于微束X射线荧光光谱测定GH4169合金铸锭中Al、Ti、Cr、Fe、Co、Ni、Nb、Mo 8种主要元素含量的方法,探究了从铸锭边缘到中心各元素的含量、最大偏析度的分布趋势,对各元素的最大偏析度、统计偏析度、统计符合度进行了统计分析,得到了GH4169合金铸锭元素含量的分布规律:Ti、Co、Nb、Mo在铸锭中心含量高,在边缘含量低;Al、Cr、Fe、Ni在铸锭边缘含量高,在中心含量低。 相似文献
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The effects of normal pulsed Nd-YAG laser irradiation on the acid resistance of human dental enamel of pits and fissures, the cleaning of the pit and fissure contents and fluoride uptake into deep pits and fissures were examined. The acid resistance of the pit and fissure enamel was evaluated by the amount of dissolved calcium per square millimeter of the surface area. The pit and fissure enamel treated with laser irradiation obtained an acid resistance 30% higher than that of the unlased controls. The cleaning effect of laser irradiation on the pit and fissure contents was compared with chemicomechanical and mechanical methods. The laser irradiation was found to clean the pits and fissures to a greater depth without alterating the shape of pits and fissures, compared with the other two methods. The distribution of calcium, phosphorus and fluoride in the enamel of the pits and fissures was then measured by electron probe microanalyzer. At the entrance and in the deep part of the pits and fissures, the fluoride content of the enamel treated with acidulated phosphate fluoride after laser irradiation was higher than that of the enamel treated with acidulated phosphate fluoride alone. These results thus suggest that Nd-YAG laser irradiation might be effective in increasing the acid resistance of the pit and fissure enamel, while removing the pit and fissure debris contents and increasing the fluoride uptake into the pit and fissure enamel. 相似文献
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针对嵩县山金矿业有限公司主矿体位于矿区构造破碎带内,前期采用上向进路充填采矿法对其进行开采时留下了高品位顶底矿柱的开采难题,矿山提出通过在各中段间施工人工假底来对这部分高品位矿柱进行回收。因此,为保证顶底柱回采稳定性和矿石回收率,建立了人工假底薄“板”力学模型,应用弹性力学理论对其失稳机理进行分析;同时在人工假底厚度确定的情况下采用安全系数法分析了进路宽度与高度对进路稳定性的影响,确定安全合理的进路宽度为3.5~4.0 m,高度为3.0~4.0 m;再对人工假底进行配筋设计,并对金属网在人工假底中不同位置时假底位移及应力场变化进行数值模拟分析,得到最安全合理的铺设位置为人工假底中部。将研究结果应用到工程实践中,结果表明人工假底的应用使矿山顶底柱得到安全高效的回采。 相似文献