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1.
针对矿山采空区的处理,采用井下移动式充填系统,具有投资小、方便快捷等特点.井下移动式混凝土充填系统采用混凝土输送泵进行井下流动充填作业方式,充填时将充填料通过矿车运输至充填地点经人工向搅拌机受料斗中定量供料,充填料浆用水来自井下水仓,通过调节阀向搅拌机定量供水,充填材料采用强制式搅拌机间歇式搅拌,搅拌均匀的充填料浆输送给混凝土泵受料斗,然后通过混凝土输送泵送至采场进行充填.经过实践检验,井下移动式混凝土充填系统在充填效果上能够满足生产需求,在未来矿山充填系统的发展上具有良好的前景与意义,具有一定的实用性和经济性. 相似文献
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随着我国社会经济的不断发展,各行业得技术水平都得到显著提升,黄金矿山充填采矿技术也是如此,黄金矿山充填采矿技术就得到十分广泛的应用。然而,在黄金矿山充填采矿技术的实际应用中还存在一些问题,减低了黄金矿山充填采矿技术的应用效果。下文就对黄金矿山充填采矿技术中存在的一些问题进行分析,指出黄金矿山充填采矿技术的应用发展,为黄金矿山充填采矿技术的优势发挥提供一定理论保障。 相似文献
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一、充填采矿法及研究充填体作用的意义1.充填采矿法应用状况充填采矿法在我国有色矿山、金矿及铀矿应用较为广泛.据1978年统计,充填法在有色矿山的使用比重为11.2%.到目前为止全国约有30多个生产和基建矿山使用充填法.充填采矿法在国外金属矿山的应用更为广泛.据1973年统计,充填法在加拿大的应用比重为29.1%.据1971年统计,美国有38个矿山不同程度上使用了充填法.据1975年统计,苏联应用充填法的比重为38%. 相似文献
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随着矿产资源开发走向深部,充填采矿法将是未来矿山采矿方法的首选。以国内外矿山充填采矿技术的发展历史和应用现状为基础,系统分析了深部矿山高采深、高地应力特点对现有充填采矿技术提出的挑战,详细列举了目前深井充填可能面临的各种问题,并探讨了解决对策;同时结合循环经济和绿色开采,提出矿山充填材料选择应向多元化和无害化方向发展,并指出与充填采矿相关的法律制度亟需制定,充填标准亟待建立,充填理论尚需完善。 相似文献
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工业废料在国内外矿山充填中的应用 总被引:1,自引:0,他引:1
近年来,随着我国采矿业的发展,胶结充填技术得到日益广泛的应用,努力降低充填成本,成为目前研究的重要课题。本文简述了工业废料在国内外矿山充填中的应用现状,重点介绍了我国三座矿山成功地利用粉煤灰、赤泥及高炉水灌进行矿山充填的情况,并论述了其胶结性能以及对充填体强度的影响。 相似文献
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介绍了矿山尾矿对于环境的危害以及改善矿山环境保护的必要性,评述了目前尾矿综合利用和尾矿胶结充填工艺的现状,叙述了高水全尾胶固充填材料与充填工艺的研究结果和使用情况,并分析了该工艺目前在岩金矿山应用存在问题和今后研究方向。 相似文献
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高采矿充填成本是影响我国矿山采矿单耗的一大因素。本文介绍了新型尾砂固结材料替代水泥在矿山胶结充填的应用。在充填体强度相同的条件下,尾砂固结剂的使用量只需普通水泥的1/2或更少。尾砂固结剂的充填工艺与矿山普遍使用的水泥胶结充填系统相同。在满足矿山对充填体强度要求的情况下,可降低充填成本,具有明显的经济效益。 相似文献
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固体充填开采技术在矿山开采中广泛应用,对提高开采效率和保障安全起到重要作用,应该引起重视。本文重点探讨了矿山工作面固体充填开采技术的应用。首先介绍了该技术手段及其优势,然后分析了固体充填开采的流程,并探讨了当前面临的问题。最后提出了优化矿山工作面固体充填开采技术应用效果的方法,希望对相关研究有所启发。 相似文献
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Theoretical models featuring cognitive processes have played a fundamental role in advancing knowledge of psychopathology and its treatment and have emphasized the importance of cognition in psychotherapy. Recognition of the importance of cognition in psychotherapy has led to a number of questions that are addressed by the articles in this special section of the Journal of Consulting and Clinical Psychology. Cognitive therapy is well represented in the articles in this special section, but therapeutic procedures that do not represent typical cognitive therapy are also examined. The articles in this special section focus on homework in the modification of cognition, cognition in the treatment of anxiety in adults and in children, change in depressive cognitions in children, cognition and rapid change in the treatment of depression, and the role of cognition in the treatment and prevention of depression that is recurrent. Examination of these types of questions holds the possibility of advances in existing treatments and the possibility of innovations in new treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Li Hui; Li Xia; Jia Ning; Cai Qing; Bai Zhuanli; Chen Rui; Song Tianbao; Zhu Zhongliang; Liu Jiankang 《Canadian Metallurgical Quarterly》2008,122(2):331
The study was designed to investigate whether nuclear factor of kappa B (NF-κB) plays regulating role in prenatal stress-induced cognitive impairment and oxidative damage in offspring rats. The authors used a rat model to study plasma levels of corticosterone and oxidative DNA damage (8-OH-dG), protein expression of P65/p50 NF-κB, and cognitive function in female and male offspring rats in middle pregnant stage and later pregnant stage. Prenatal stress affected the capability of learning and memory in the offspring, especially in later stage stressed female offspring. The levels of corticosterone and 8-OH-dG were enhanced in response to stress. Both middle and later stage stresses induced a significant decrease in P65 expression and a significant increase in P50 expression in female offspring. In addition, later stage stress induced a significant decrease in P50 expression in male offspring. These results suggest that NF-κB complex may be acting in a positive regulatory fashion in prenatal stress-induced cognitive impairment and that oxidative DNA damage may exacerbate the activation of NF-κB. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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以水稻土—地表水铀含量为视角,从水稻土剖面铀含量分布规律、水稻土与下伏岩体稀土元素特征、不同河流不同河段水稻土—地表水—稻米铀含量特征、水稻土与稻米铀含量关系4个方面研究721铀矿区稻米铀含量成因。结果表明,水稻土剖面铀含量从表层至半风化花岗质基岩层呈明显降低的特征,说明水稻土铀含量高的原因不是土壤母质铀含量高;岩石与水稻土稀土元素标准化模式均表现为向右倾斜型,均属轻稀土富集型,轻稀土分馏明显,表明水稻土为还原环境,吸附作用较强;不同河流不同河段水稻土—地表水—稻米铀含量平均值的特性均为上游最低、中游最高、下游次之。铀矿区地表水环境符合铀元素在水稻土中被平衡吸附的动力学条件,有利于铀元素在矿区内河流中游地区的水稻土中沉淀富集;正在采矿区水稻土与稻米铀含量具有高度的空间耦合性,呈指数正相关关系,相关系数0.749。矿区内河流沿岸稻米铀含量的分布特征是由铀元素的迁移途径决定的"采矿活动(铀尾矿露天堆放)→地表水→水稻土"。 相似文献
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Octave Chanute was one of the leading civil engineers in the United States in the period between 1850 and 1890. His work on eastern and western railroads was unsurpassed. He began his bridge building career in 1856 and designed his last major bridge in 1888. Starting in 1890, he began his study in the work that others conducted in the area of manned flight and designed and tested many of his own gliders. He later assisted the Wright Brothers in their experiments in Dayton and at Kitty Hawk. 相似文献
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摘要:对链箅机回转窑工艺中各段球团样品进行实验分析,研究了氯元素和硫元素在链箅机回转窑工艺中的迁移规律,明晰了烟气中HCl的生成机制。结果表明,球团原料中的氯元素主要是以NaCl的形式存在,氯元素有一部分在链箅机抽风干燥段会转变成HCl气体并进入烟气,一部分在链箅机预热Ⅱ段之后以NaCl的形式汽化进入烟气,剩余的氯元素仍以NaCl的形式存在于成品球团矿中。烟气中的HCl气体是在抽风干燥段,由富含SO2的烟气与含水球团料层中的NaCl发生反应生成的,烟气中SO2转变成Na2SO4重新固定于料层中。在预热Ⅰ段和预热Ⅱ段,烟气中的SO2与原料中碳酸钙分解生成的游离CaO反应生成CaSO4,也会重新固定烟气中的SO2。 相似文献
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Humphrey Stephen E.; Nahrgang Jennifer D.; Morgeson Frederick P. 《Canadian Metallurgical Quarterly》2007,92(5):1332
The authors developed and meta-analytically examined hypotheses designed to test and extend work design theory by integrating motivational, social, and work context characteristics. Results from a summary of 259 studies and 219,625 participants showed that 14 work characteristics explained, on average, 43% of the variance in the 19 worker attitudes and behaviors examined. For example, motivational characteristics explained 25% of the variance in subjective performance, 2% in turnover perceptions, 34% in job satisfaction, 24% in organizational commitment, and 26% in role perception outcomes. Beyond motivational characteristics, social characteristics explained incremental variances of 9% of the variance in subjective performance, 24% in turnover intentions, 17% in job satisfaction, 40% in organizational commitment, and 18% in role perception outcomes. Finally, beyond both motivational and social characteristics, work context characteristics explained incremental variances of 4% in job satisfaction and 16% in stress. The results of this study suggest numerous opportunities for the continued development of work design theory and practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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矿区环境的污染防治与生态修复是促进我国“十四五”生态文明建设的重要内容之一,促进风险管控与修复技术集成是治理矿山污染的必然趋势。回顾了近年来我国矿区污染的主要修复类与管控类技术,总结了风险管控模式下矿区污染场地一般修复思路,并在此基础上归纳概括了4种我国矿区的修复管控模式与实施案例,包括基于污染物时空分布、迁移转化规律、场地利用方式及风险等级的矿区修复管控模式。以期为未来我国建立涵盖风险标准体系与技术体系的场地治理模式提供参考与支撑。 相似文献
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The paper considers carbothermal solid state reduction of manganese, titanium and aluminium oxides in argon, helium and hydrogen. The difference in reduction in helium and argon was reflected by different diffusion coefficients of gaseous reactants and products, which are much higher in helium than in argon. When carbothermal reduction took place in hydrogen, it was involved in the reduction process by reducing oxides to suboxides and forming methane. Manganese and titanium oxides were reduced to carbide Mn7C3 and oxycarbide Ti(OxC1‐x) correspondingly, while products of alumina reduction included carbide Al4C3 and vapours of Al and Al2O, which were re‐oxidised to Al4O4C outside the reactor and deposited in the lower temperature zone. Gas atmosphere had a profound effect on the extent and rate of reduction. This effect was different in reduction of different oxides. Reduction of manganese oxides was the fastest in hydrogen, and faster in helium than in argon. Reduction of titania in argon and helium proceeded with about the same rate and was much faster in hydrogen than in the inert atmospheres. The rate and extent of alumina reduction in hydrogen and helium were higher than in argon, although no significant difference was observed in alumina reduction in hydrogen and helium. This reflects differences in reduction mechanisms, which are discussed in the paper. 相似文献
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Kim Ji-Yeon; McHale Susan M.; Crouter Ann C.; Osgood D. Wayne 《Canadian Metallurgical Quarterly》2007,43(4):960
The links between changes in sibling conflict and intimacy and changes in perceived peer social competence and depression symptoms were examined from middle childhood through adolescence. Participants were mothers, fathers and first- and second-born siblings from 197 White, working/middle class, two-parent families. Peer competence peaked in early adolescence and then declined; depression symptoms were high in middle childhood and, for girls, in middle adolescence. Controlling for parent-offspring relationships and sibling and parent adjustment, increases in sibling conflict were linked to increases in depression symptoms, and increases in sibling intimacy were linked to increases in peer competence and, for girls, decreases in depression symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Dahlstrom W. Grant; Meehl Paul E.; Schofield William 《Canadian Metallurgical Quarterly》1986,41(7):834
Presents an obituary for Starke Rosecrans Hathaway. Hathaway obtained both his undergraduate and master's level training with James P. Porter at Ohio University in Athens. He earned his undergraduate degree in psychology in 1927 and his master's degree in 1928. Porter persuaded him to remain in Athens as an instructor in psychology and physiology; by 1929 he held the rank of assistant professor. Hathaway's original interests in engineering persisted; he perfected and marketed a chronoscope, a psychogalvanometer, and electrical stimulation and recording devices for the study of neural processes. It is interesting to recall that one of the first uses to which Hathaway had put his psychogalvanometer was as a lie detector in helping police in Athens to solve a murder case. Hathaway's contributions to clinical psychology were recognized at the national level by the APA's Division of Clinical Psychology, which conferred its Distinguished Scientific Contribution Award in 1959 and elected him as its president in 1963. Elected to Sigma Xi and Phi Beta Kappa, an ABPP diplomate in clinical psychology, he was awarded honorary doctorates by Ohio University in 1966 and by Ohio State University in 1972. His honors were capped in 1977 when the APA conferred its award for Distinguished Contribution for Applications in Psychology. Hathaway retired from the University of Minnesota in 1971. He died at his home in Minneapolis on July 4, 1984. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献