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61.
How will biomining be applied in future? 总被引:1,自引:1,他引:0
C.L.BRIERLEY 《中国有色金属学会会刊》2008,18(6):1302-1310
This paper reviews the current status of commercial biomining operations around the world, identifies factors that drive the selection of biomining as a processing technology, describes challenges to exploiting these innovations, and concludes with a discussion of biomining's future. Biomining is commercially applied using engineered dumps, heaps and stirred tanks. Overcoming the technical challenges of lowering costs, processing low-grade, low-quality and complex ores and utilizing existing capital investments at mines requires better understanding of microbial activities and innovative engineering. Surmounting biomining commercial challenges entails improved mining company/biomining innovator cooperation and intellectual property control. 相似文献
62.
Selective flocculation of fines 总被引:1,自引:1,他引:0
P.Somasundaran V.RunkanaLangmuir Center for Colloids Interfaces Columbia University New York NY USA 《中国有色金属学会会刊》2000,10(Z1):8-11
1 INTRODUCTIONAstheearth’sresourcesarebeingconsumedsteadilyandasdemandformineralproductscontinuestoincrease ,theneedtoutilizelow gradeoresmoreefficientlyhasbecomemoresevere .Thisindeedre sultsinthegenerationofalargequantityoffineparti clesduringminingand… 相似文献
63.
1.IntroductionThebajsicprincipleofelectricresistancemethod(hot-wiremethod)isthattheresistivityofac--Feisindirectproportiontoitscarboncontentwheninthehightemperatureiso-phaseAustatine.Inpractical,apieceofwire(normallyit'sdiameterislessthan0.3mm)isusedassensortomeasureatmospherecarbonpotential.Buttheresistancevalueofthewiredoesnotdirectlyreflecttheatmospherecarbonpotentialbuttheaveragecarboncontentofthewire,sothat,therelationshipbetweenaveragecarboncontentofthewireandatmospherecarbonpotentialbe… 相似文献
64.
通过对文献进行比较性回顾,分析了数字化设计技术发展的2个关键转折期,以探索其共通的主题和平行的发展轨迹。第一个转折是将微型计算机引入消费市场,并随之在设计领域使用CAD软件;第二个转折是在更广泛的建筑信息模型(BIM)范围内纳入使用景观信息模型(LIM)。在数字技术和社会科学的框架内比较了2个时期对设计过程、生产率、人机关系、组织层级和设计创新的影响,同时以对景观设计公司人员的采访作为补充,帮助理解当代将BIM/LIM纳入景观设计实践的主要挑战。 相似文献
65.
FENG ZuoHai WANG ChunZeng LIANG JinCheng LI JunZhao HUANG YongGao LIAO JiaFei & WANG Rui School of Earth Sciences Guilin University of Technology Guilin China Key Laboratory of the Center of Guangxi Geologic Engineering College of Arts Sciences University of Maine at Presque Isle Presque Isle Maine USA 《中国科学:技术科学(英文版)》2011,(1)
The Guposhan-Huashan batholith was emplaced during transition from Tethysian tectonic regime to Pacific tectonic regime in the Middle-Late Jurassic. The regional EW-striking Yishan-Quannan basement deep fault zone, associated with the Tethysian regime, is thought likely to control the formation of the batholith. The development of the batholith was, however, achieved when the Pacific tectonic extensional regime dominated. The batholith consists of seven individual intrusive units that were emplaced subseque... 相似文献
66.
在当今世界,森林是捕获碳以减少温室气体(GHG)净排放的主要场所,其通过这种方式减缓或扭转了全球变暖,从而缓和了变暖的负面后果。目前这种能力在多大程度上来自那些位于山地上的森林?这种能力是否可以或应该得到进一步的提升?怎样才能提高我们对山地森林碳捕获潜力的评估能力,以应对现在和将来的不同情况?许多国家已经承诺到2050年实现净零排放,主要是使能源生产中排放的CO2不超过他们能够吸收、保留乃至封存的量。因此,封存与减排的合作关系被提升了,减排通过向核电和可再生能源的转变以及通过能源用户的效率来实现。此外,在我们寻找更清洁和更划算的能源技术时,封存提供了一个近期的缓冲。从长远来看,封存可能会变得更加有效,从而更能分担温室气体的减排任务。尽管相关研究日益增多,但是还没有形成一套针对海洋、湿地、土壤和森林生物群落的封存潜力的评估方法。探讨与山林封存潜力评估需求相关的必要性和隐患。提高山林碳封存潜力的决心取决于:1)实现这一目标的难易程度;2)实现这一目标的机会成本;3)可在山地景观上进行的替代性使用和活动的效果和相互关系;4)替代性的海洋和陆地碳汇的比较效果;5)能源部门本身的去碳方法的成效。 相似文献
67.
正城市设计是众多设计学科的有机融合,SWA集团充分利用60余年的悠久设计经验,以跨学科的视角,不断完善和丰富城市设计实践。在持续发展的过程中,将多年的实践经验融入规划、城市设计和风景园林,形成SWA完善的城市设计体系。其中,高性能基础设施是城市设计成功的关键要素,而新技术正快速推动城市设计并以前所未有的方式改变生活。更繁荣未来的实现,始于今天的综合性的规划。 相似文献
68.
Variable nozzle turbine (VNT) has become a popular variable geometry turbine (VGT) technology for the diesel engine application. Nozzle clearance, which can’t be avoided on the hub and shroud side of the VNT turbine due to the pivoting stators, can lead to turbine performance deterioration. However, its mechanism is still not clear. In this paper, numerical investigation, which is validated by experiment, is carried out to study the mechanism of the nozzle clearance’s effect on the turbine performance. Firstly, performance of the mixed flow turbine with fixed nozzle clearances tested on flow bench. Performance of the tested turbine with the same nozzle clearance is numerically simulated. The numerical result agrees well with the test data, which proves correct of the numerical method. Then the turbine performance with different nozzle clearances is numerically analyzed. The research showed that with nozzle clearance, flow loss in the nozzle increases at first and it reaches the maximum value when the clearance ratio is 5%. Flow at the exit of the nozzle becomes less uniform with nozzle clearance. The negative incidence angle of the rotor also increases with nozzle clearance and leads to more incidence angle loss in the rotor. The low energy fluid formed in the nozzle due to the nozzle clearance migrates from hub to shroud side in the rotor, which is another main reason for the rotor’s performance degradation. The present research exposed the mechanism of the dramatically decrease of the turbine performance with nozzle clearance: (a) The loss associated with the nozzle leakage increases with the nozzle clearance; (b) The flow loss grows up quickly in the rotor due to the incidence angle loss and migration of the low energy fluid from hub to shroud side. 相似文献
69.
水冷型和风冷型日晒色牢度试验机 总被引:2,自引:0,他引:2
日晒色牢度试验机自诞生以来,经历了转鼓式风冷、转鼓式水冷和平板式风冷三个时期。该文重点分析了风冷和水冷机型的优缺点,并结合日晒色牢度测试的常用标准和实际应用情况,就风冷和水冷机型对检测结果的影响和不同机型之间检测结果的可比性问题,进行了讨论。 相似文献
70.
Junsheng LU Xiaodong LIU Wenjie ZHENG Baorong WU Hui BI Central Iron Steel Research Institute Beijing ChinaGuijin WANG Dept.of Materials Science Engineering University of Pennsylvania Philadelphia PA USA 《材料科学技术学报》1993,9(4):293-296
The influence of the volume fraction of tempered martensite on magnetomechanical damping of theferritic matrix in dual-phase alloys was studied.The experimental results showed that(1)dual-phase damping alloy is of good combination of strength and toughness: (2)good damping ca-pacity(Q~(-1)≥5.0×10~(-3))can be obtained in dual-phase alloys only when the volume fraction oftempered martensite was controlled properly.The effect of martensite on magnetomechanical damp-ing of the ferritic matrix was analysed.The damping capacity of dual-phase alloys was related to thevolume fraction V_m of tempered martensite by Q_~(-1)=Q_~(-1) (1-V_m/1+BV_m)at small vibration strainamplitudes ε_A≤5.0×10~(-6). 相似文献