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Selective depression mechanism of ferric chromium lignin sulfonate for chalcopyrite–galena flotation separation

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 489-497页

作者： jin-sheng Yu Run-qing Liu Li Wang wei Sun Hong Peng Yue-hua Hu School of Minerals Processing and Bioengineering Central South University School of Chemical Engineering The University of Queensland

Selective recovery of chalcopyrite–galena ore by flotation remains a challenging *** development of highly efficient,low-cost,and environmentally friendly depressants for this flotation is necessary because most of available reagents(e.g.,K_2Cr_2O_4)are expensive and adversely affect the *** this study,ferric chromium lignin sulfonate(FCLS),which is a waste-product from the paper and pulp industry,was introduced as a selective depressant for galena with butyl xanthate(BX)as a *** show that the residue recovery of Pb in Cu concentrate was substantially reduced to 4.73%using FCLS compared with 10.71%using the common depressant K_2Cr_2O_*** underlying mechanisms were revealed using zeta-potential measurements and X-ray photoelectron spectroscopy(XPS).Zeta-potential measurements revealed that FCLS was more efficiently absorbed onto galena than onto *** measurements further suggested that FCLS enhanced the surface oxidation of galena but prevented that of ***,FCLS could be a potential candidate as a depressant for chalcopyrite–galena flotation because of its low cost and its lack of detrimental effects on the environment.

关键词： chalcopyrite galena depressant flotation separation

Measurement of pore diffusion factor of porous solid materials

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Petroleum Science 2022年第4期19卷 1897-1904页

作者： jin-Tao Guo Ya-Qian wei sheng-Li Chen wei Sun Ting-Ting Fan Ming-Ri Xu Chang-Cheng Zhang State Key Laboratory of Heavy Oil Processing and Department of Chemical EngineeringChina University of Petroleum-BeijingBejing102249China Petrochemical Research Institute of PetroChina Company Limited Daqing163000HeilongjiangChina

Internal diffusion of molecules in porous materials plays an important role in many chemical ***, the pore diffusion capacity of porous materials cannot be measured by conventional catalyst characterization methods. In the present paper, a pore diffusion factor, the ratio of the diffusionconstriction factor to the pore tortuosity of the porous materials, was proposed to measure the diffusion ability of pores inside solid materials, and a method was proposed for measuring the diffusion factor using a well-defined and uniform pore size material as a reference. The diffusion factor was calculated based on the effective diffusion coefficients and the diffusion-constriction factor and pore tortuosity of the reference porous materials. The pore diffusion factor measurement can be performed at room temperature and atmospheric pressure. The pore diffusion factor of conventional porous materials was found to be much smaller than 1, indicating that there is a lot of room for improving the diffusion ability of the conventional catalysts and adsorbents, and could be significantly increased through adding small number of fibers into the conventional porous materials as template.

关键词： Porous materials Well-defined and uniform pore structure materials Internal diffusion Diffusion factor Tortuosity

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《中国学术腐败批判》讨论专辑

云梦学刊 2003年第1期24卷 13-29页

作者：周祥森杨玉圣张伟然井建斌杨守建 <史学月刊>编辑部河南开封475001 北京师范大学历史系北京100875 复旦大学中国历史地理研究所上海200031 天津市党校文史部天津300001 中国青年政治学院新闻系北京100089

“学者研究”从本期改版为“当代学术史研究”专栏。改版后,本栏目将既继续对当代一流学者作个案研究,又对当代学术争鸣、学术流变、学术现象作宏观扫描,且特别注意将个体学者的研究置于宏观的学术史背景之下来进行。对学风文风问题的... 详细信息

“学者研究”从本期改版为“当代学术史研究”专栏。改版后,本栏目将既继续对当代一流学者作个案研究,又对当代学术争鸣、学术流变、学术现象作宏观扫描,且特别注意将个体学者的研究置于宏观的学术史背景之下来进行。对学风文风问题的关心和讨论,是学术界、教育界近来最引人注目的热点话题之一。本期发表周祥森、杨玉圣、张伟然、井建斌、杨守建诸先生围绕《中国学术腐败批判》一书而开展的热烈讨论的专题文章。这些讨论虽说围绕一本新书而展开,但所涉及的主题和问题却是带有一定的普遍性和较强的现实性的,值得关注。

关键词：专题讨论《中国学术腐败批判》

Effect of tempering on carbides and hydrogen embrittlement in E690 high strength marine structural steel

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Journal of Iron and Steel Research International 2022年第10期29卷 1669-1682页

作者： Yi Luo wei Li Peng-wei Zhou Yuan-tao Xu Hui-yong Pang Ning Zhong Hui-sheng Jiao Xue-jun jin Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China Institute of Advanced Steels and Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China China Wuyang Iron and Steel Co. Ltd.Pingdingshan462500HenanChina School of Materials Science and Engineering Shanghai Maritime UniversityShanghai200120China TESCAN CHINA Shanghai200240China

The effect of tempering on carbides and hydrogen embrittlement in E690 high strength marine structural steel has been *** steel was tempered at 600℃ for 1–3 *** characterization was carried out to characterize the microstructure,especially the dislocation density and grain *** hydrogen permeation test and thermal desorption spectroscopy test were also *** dislocation density decreases,the amount of carbide increases,and carbides(M_(23)C_(6) and MX)coarsen with the tempering time *** tempered at 600℃ for 3 h,the diffusible hydrogen trapped by lattice and dislocation decreases while the non-diffusible hydrogen trapped by carbides increases,leading to the best hydrogen embrittlement resistance,although hydrogen diffuses rapidly due to the reduction of dislocation *** the fracture mode changes from a combination of brittle cleavage and ductile dimpled fracture to fully ductile dimple fracture under hydrogen charging ***,a phenomenon that hydrogen accelerates the dislocations movement of the steel during deformation was observed,which is related to the fact that hydrogen enhanced localized plasticity mechanism.

关键词： High strength marine structural steel Carbide Tempering Hydrogen embrittlement Thermal desorption spectroscopy

Source model of the 2018 M_(w)7.5 Papua New Guinea earthquake constrained by InSAR measurements: Insight into a blind rupture beneath the New Guinea Highlands

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Geodesy and Geodynamics 2024年第4期15卷 315-325页

作者： wei Chen Tianchen sheng wei Xiong Key Laboratory of Earthquake Geodesy Institute of SeismologyChina Earthquake AdministrationWuhan 430071China Qinghai Provincial Basic Surveying and Mapping Institute Xining 810001China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

The Southern Highland Fold and Thrust Belt(SHFTB),the boundary of the Australian plate and the New Guinea Highland block,significantly contributes to the convergent deformation along the plate ***,due to the lack of observation data,the detailed slip pattern of the SHFTB and the orogenic mechanism beneath the New Guinea Highlands remains *** 25 February 2018,the M_(w)7.5 Papua New Guinea(PNG)earthquake struck the southeastern segment of the *** detailed rupture characteristics of this event is significant for further clarifying the inter-seismic slip pattern along the ***,the coseismic deformation field of this earthquake was obtained using high-resolution ALOS-2 satellite *** find that the 2018 M_(w)7.5 PNG earthquake ruptured a large-scaled fault(SHFTB)extending to the lower crust(deeper than 20 km)beneath the New Guinea Highlands,with a dip angle of 24°.The slips on the fault plane are equivalent to moment magnitudes of M_(w)*** major asperities with thrust-dominated slip of up to 3.94 m are detected on the fault *** finding implies that the slip pattern on the eastern segment of the SHFTB is dominated by thrust,rather than with significant sinistral movement,as previously *** tectonic deformation across the New Guinea Highlands is possibly concentrated on the large-scale fault SHFTB and primarily controls the intra-continental orogeny in the central Papua New Guinea.

关键词： 2018M_(w)7.5PapuaNewGuineaearthquake The Southern Highlands Fold-and-Thrust Belt InSAR Slipdistribution Seismicrisk

Simulation of thermoacoustic waves by a pressure-based algorithm for compressible flows

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Acta Mechanica Sinica 2012年第3期28卷 819-824页

作者： wei Li Qi-sheng Chen Key laboratory of Microgravity Institute of MechanicsChinese Academy of Sciences15 Beisihuan West Road100190 BeijingChina

A modified SIMPLEC method which can solve compressible flows at low Mach number is introduced and used to study thermoacoustic waves induced by a rapid change of temperature at a solid wall and alternating- direction flows generated by thermoacoustic effects in a ta- pered resonator. The results indicate that the algorithm adopted in this paper can be used for calculating com- pressible flows and thermoacoustic waves. It is found that the pressure and velocity in the resonator behave as stand- ing waves, and the tapered resonator can suppress high- frequency harmonic waves as observed in a cylindrical res- onator.

关键词： Compressible flow Thermoacoustic wave Resonator. SIMPLEC

Late Oligocene Melia(Meliaceae) from the Nanning Basin of South China and it's biogeographical implication

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Journal of Palaeogeography 2021年第3期10卷 334-340页

作者： wei-Qiu Liu sheng-Lan Xu Qiong-Yao Fu Cheng Quan Jian-Hua jin School of Ecology Sun Yat-sen UniversityGuangzhou 510275Guangdong ProvinceChina State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources School of Life SciencesSun Yat-sen UniversityGuangzhou 510275Guangdong ProvinceChina State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyCASNanjing 210008Jiangsu ProvinceChina Natural History Museum of Guangxi Nanning 530012Guangxi Zhuang Autonomous RegionChina School of Earth Science and Resources Chang'an UniversityXi'an 710054Shaanxi ProvinceChina

Melia L. is a small genus of only 2–3 species, which is native to Indo-Malesia, India, Pakistan and southern parts of tropical Africa. Fossil records of Melia are known from the early Miocene to the Pleistocene. Here we describe some mummified fossil endocarps of Melia from the upper part of the Yongning Formation(late Oligocene) in Nanning Basin, South China. These well-preserved stony endocarps are 8–14 mm long and 5–9 mm wide, and have 5 locules with a single spindle seed per locule. We interpret these endocarps as the internal remains of a Melia drupe, and assign them as a new species: M. santangensis sp. nov. This is the only fossil record of anatomically preserved Melia found in China, and also the oldest fossil record of Melia so far reported globally. The fossil record confirms the presence of Melia in Asia at the late Oligocene, and provides evidence supporting the distribution and dispersal hypothesis of the Meliaceae.

关键词： Melia Endocarp Mummified fruit Nanning Basin Paleogene

Seismic performance of two-story subway station structures with different isolating systems

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Earthquake Research Advances 2022年第4期2卷 60-71页

作者： Haiyang Zhuang wei Wang Liguo jin sheng Li Guoxing Chen School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang330013China Civil Engineering and Earthquake Disaster Prevention Center of Jiangsu Province Nanjing210009China Institute of Geotechnical Engineering Nanjing Tech UniversityNanjing210009China Institute of Geophysics China Earthquake AdministrationBeijing100081China

When the sliding bearing is fixed only at the top of the middle column of the underground structure,the cracks at the side end of the middle plate should be aggravated while the seismic damage of the mid-column should be *** enhance the seismic performance of the mid-plate,a new isolation design method has been mentioned while the elastic sliding bearings are set at the top of the mid-columns and between the side end of the mid-plate and the side wall at the same *** establishing a nonlinear finite element analysis model for the static-dynamic coupling interaction system,the seismic response characteristics of the cast-in-place station structure without a sliding bearing have been analyzed and compared with those of the station structure with the sliding bearing fixed only at the top of the middle columns,and those of the station structure with sliding bearing be fixed between the mid-plate and the sidewall at the same *** results show that the new isolation station structures suffer fewer earthquake damages at the mid-plate and mid-columns at the same time,which can improve the overall seismic performance of the subway station structure.

关键词： Subway station structure Seismic performance Elastic sliding bearing Seismic mitigation effect Numerical modelling

MHz cut-off frequency and permeability mechanism of iron-based soft magnetic composites

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Chinese Physics B 2024年第9期33卷 560-564页

作者： Xiao-wei jin Tong Li Hui-Gang Shi De-sheng Xue Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education LanzhouUniversityLanzhou 730000China

The lack of soft magnetic composites with high power density in MHz frequency range has become an obstacle in the efficient operation of the electrical and electronic ***,a promising method to increase the cut-off frequency of iron-based soft magnetic composites to hundreds of MHz is *** cut-off frequency is increased from 10 MHz to 1 GHz by modulating the height of the ring,the distribution of particles,and the particle *** mechanism of cut-off frequency and permeability is the coherent rotation of domain modulated by inhomogeneous field due to the eddy current *** empirical formula for the cut-off frequency in a magnetic ring composed of iron-based particles is established from experimental *** work provides an effective approach to fabricate soft magnetic composites with a cut-off frequency in hundreds of MHz.

关键词： cut-off frequency permeability eddy current effect soft magnetic composites