甘肃金川铜镍矿石中MgO对浮选的影响   总被引：7，自引：0，他引：7  

马建青  刘星 《云南地质》2005,24(4):402-406

金川铜镍矿浮选精矿中MgO高,影响闪速熔炼。对金川主力矿山二矿区矿石中MgO分布特征与赋存状态的研究,分析影响浮选过程中MgO难以抑制原因。认为矿石本身MgO含量高、矿石蚀变严重、含镁矿物自然可浮性的良好是造成精矿中MgO高的主要原因。提出研究含镁矿物的浮选特性和矿石的矿物组成特点是精矿降镁的前提。  相似文献   

Propagation and attenuation characteristics of various ground vibrations     

Dong-Soo Kim  Jin-Sun Lee   《Soil Dynamics and Earthquake Engineering》2000,19(2)

In order to effectively control vibration related problems, the development of a reliable vibration monitoring system and the proper assessment of attenuation characteristics of various vibrations are essential. Various ground vibrations caused by train loading, blasting, friction pile driving and hydraulic hammer compaction were measured using 3D geophones inside of the borehole as well as on the ground surface, and the propagation and attenuation characteristics of various source generated vibrations were investigated by analyzing particle motions. For the geometric modeling of various vibrations, the types of various sources and their induced waves were characterized and the geometric damping coefficients were determined. The measured attenuation data matched well with the predicted data when using the suggested geometric damping coefficient, and the estimated soil damping ratios were quite reasonable taking soil type of the site and experiencing strain level into consideration.  相似文献   

地磁Z分量日变"低点位移"异常成因分析   总被引：2，自引：0，他引：2  

胡久常 《地震》2011,31(2):79-86

本文基于对地磁Z分量日变"低点位移"异常和太阳静日变化内外源场等效涡旋电流体系时空演化特征的分析,提出了"电磁炉效应"假说,以解释地磁Z分量日变"低点位移"异常的成因.本文认为,起源于地球内部和外部涡旋电流体系所产生的太阳静日变化Sq,作为一个持续的交变磁场,切割地壳深部的高导低速层,形成涡旋电流并产生热能,致使高导低...  相似文献   

Optical polarization observations with the MASTER robotic net     

《New Astronomy》2014

  相似文献   

一种简而易制的二圆柱面反射式摄谱仪准直畸像系统     

路声东 《中国天文和天体物理学报》1992,(3)

本文是对于摄谱仪准直畸像光学系统研究的继续和深入,认真分析了Wynne的卡焦摄谱仪畸像系统的设计思想,认为可以避免像他那样将畸像系统设置在卡焦前会聚光束中(致使畸像系统变得复杂),而设置在摄谱仪准直光路中更为合理.作者与蒋世仰教授曾首次提出了准直畸像系统的概念,现在对于其中所提的反射系统的工作有所推进,寻求得到了一种结构简单、易于制作的系统.它仅由两个圆柱面构成,是一种柱面的类Mersenne系统.文中说明了在一定的条件下可以由圆柱面代替柱面Mersenne系统的抛物柱面(该系统在中已被提出过)、这种类Mersenne系统既可置于折轴摄谱仪中,亦可置于卡焦摄谱仪中,且能在大直径准直光束中起较剧烈的畸像作用,当然也具有反射系统所固有的优点——接收更宽的波段,特别在非可见光区优于透射系统.给出的算例说明该系统的准直误差极小.  相似文献   

Far-Infrared/Submillimeter Astronomical Interferometry with Spaceborne Tether Formations     

Enrico Lorenzini  Claudio Bombardelli  Mario Cosmo  Martin Harwit  David Leisawitz  Rodger Farley  Stephen Rinehart  David Quinn  David Miller 《Astrophysics and Space Science》2006,302(1-4):225-239

Through the continuing development of improved detectors and detector arrays, far-infrared/submillimeter astronomical space missions have had enormous successes in recent years. Despite these advances, the diffraction-limited angular resolving power has remained virtually constant. The advent of telescopes with apertures of several meters will improve this capability, but will still leave image resolution many orders of magnitude poorer than in most other spectral ranges. Here we point out that the only foreseeable way to improve image quality to rival that of modern optical telescopes will be with interferometers whose light collectors are connected by tethers. After making the scientific case for high spatial resolution far-infrared/submillimeter imaging and the use of interferometry as the most immediate way of producing results, we discuss recent advances in dynamic analysis and control of tethered formations, and argue that the further development and testing of tethers in space is a first step toward providing improved far-infrared/submillimeter angular resolution and astronomical image quality.  相似文献   

1995年7月12日中缅边界7.3级地震的长、中、短临预报及天文因素     

叶展 《天文研究与技术》1997,(3)

１９９５年１月１７日对滇西南地震进行了预报，并小结了１９９５年７月１２日中缅边界７．３级地震预报。预报时不仅运用了地震学的知识，同时还运用了天文方面的知识。  相似文献   

Steel stocks and flows of global merchant fleets as material base of international trade from 1980 to 2050     

《Global Environmental Change》2022

Exploring the dynamic changes of steel from the ships is critical for developing sustainable strategies for waste management of shipping industry. However, the information of stocks and flows of ships and related steel is currently unavailable, hindering the sustainable development of shipping industry. By collecting dispersed information on production, use, material composition, and end-of-life management of five types ships, we first estimated the historical steel stocks and flows respect to global ships from 1980 to 2019, and further projected the amount of steel scraps from shipbreaking by 2050. The steel stocks of ships increased by 2.6 times from 208.4 Mt in 1980 to 542.9 Mt in 2019. The top 2 regional contributors, Asia and Latin America & the Caribbean, were together responsible for about half of the total increase. A transition from oil tankers to container ships and bulk carriers reduced the in-use steel stock due to the lower steel intensity of the latter. The rapid increase of ship stocks after year 1980 led to significant increase of steel scrap in the 2010 s, reaching 10.1 Mt/year in 2019. Our projections showed that the steel from scrapped ships worldwide will increase by around 4-fold to 40.4–47.3 Mt/year by 2050, which imposed a great challenge on coordination of recycling ship-related steel and require long-term planning on ship recycling facility development. By identifying the stocks and flows of ships and related steel, this study provides insights for the steel waste and recycling management of end-of-life ships worldwide.  相似文献   

地质旋回与天文周期   总被引：4，自引：0，他引：4  

杨学祥 《东北地震研究》1996,12(2):24-30

太阳辐射量变化与地质旋回的对应关系表明，太阳辐射不仅是形成地磁场内外磁尾和地壳与内核反向振动的原因，而且是核幔电磁耦合和能量交换的原因，在这个过程中，太阳向地球既输送了大量热能，又输送了大量电磁辐射能，这是我们通过天文周期预测未来地质变动的理论基础。  相似文献   

Material screening and selection for XENON100     

E. Aprile  K. Arisaka  F. Arneodo  A. Askin  L. Baudis  A. Behrens  K. Bokeloh  E. Brown  J.M.R. Cardoso  B. Choi  D. Cline  S. Fattori  A.D. Ferella  K.L. Giboni  A. Kish  C.W. Lam  J. Lamblin  R.F. Lang  K.E. Lim  J.A.M. Lopes  T. Marrodán Undagoitia  Y. Mei  A.J. Melgarejo Fernandez  K. Ni  U. Oberlack  S.E.A. Orrigo  E. Pantic  G. Plante  A.C.C. Ribeiro  R. Santorelli  J.M.F. dos Santos  M. Schumann  P. Shagin  A. Teymourian  D. Thers  E. Tziaferi  H. Wang  C. Weinheimer  M. LaubensteinS. Nisi 《Astroparticle Physics》2011,35(2):43-49

Results of the extensive radioactivity screening campaign to identify materials for the construction of XENON100 are reported. This dark matter search experiment is operated underground at Laboratori Nazionali del Gran Sasso (LNGS), Italy. Several ultra sensitive High Purity Germanium detectors (HPGe) have been used for gamma ray spectrometry. Mass spectrometry has been applied for a few low mass plastic samples. Detailed tables with the radioactive contaminations of all screened samples are presented, together with the implications for XENON100.  相似文献