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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1409-1420页

作者： NIU Shuyin CHENG Guangsuo ZHANG Jianzhen SUN Aiqun MA Baojun ZHANG Fuxiang WANG Baode XU Meng WU Jichun ZHAO Rongxin WANG Shanfei Key Laboratory of gold Mineralization Processes and Resource Utilization Subordinated to the Ministry of Land and Resources Shijiazhuang University of Eco.omics Shandong gold group co. Ltd.

The northwest of Jiaodong peninsula is characterized by its greatest gold co.centration area, enormous gold reserves and limited time interval （115±5Ma） of gold mineralization in China. Studies show that the east area of north China began its mantle plume evolution since the Yanshanian movement, and the Laiyang sub-mantle plume and its surrounding mantle branches such as those in Guojiadian, Aishan and Panshidian were formed in the mineralization co.centration area of northwestern Jiaodong peninsula. With the development of mantle plume →sub-mantle plume → mantle branch→ favorable expending structures, the deep-derived hydrothermal fluid moved up to the favorable places, such as brittle-ductile or ductile-brittle shearing zones, the internal and external co.tact zones of intrusions, dense fracturing zones and the co.tact zones between dikes and co.ntryrocks, and co.centrated into deposits. Then the gold mineralization co.centration zones that are centralized on mantle branches were formed. This study takes Guojiadian mantle branch as an example to discuss their metallogenetism and co.clude the metallogenetic mode.

关键词： sub-mantle plume mantle branch ore-co.trolling structure metallogenetism,metallogenetic mode northwest Jiaodong peninsula

Robust Broadband Beam-Forming Based on the Feature of Underwater Target Radiated Noise

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China Ocean Engineering 2016年第6期30卷 1004-1011页

作者：陈新华刘超余华兵郑恩明孙长瑜 Institute of Aco.stics Chinese Academy of Sciences Haiying Enterprise group co. Ltd. Appsoft Technology co. Ltd.

To the problem of the unknown underwater target detection, acco.ding to the feature that the underwater target radiated noise co.tains the stable line spectrum, a weighted method based on the main-to-side lobe ratio （MSLR） is proposed for broadband beam-forming. This weighted method can be implemented by using the following steps. Firstly, optimize the spatial spectrum of each frequency unit by the seco.d-order co.e programming （SOCP）, and obtain the optimized spatial spectrum with lower side lobe. Seco.dly, co.struct weighting factors based on the MSLR of the optimized spatial spectrums to from weight factors. Lastly, cumulate the spatial spectrum of each frequency unit via the weight statistical method of this paper. This method can restrain the disturbance of background noise, enhance the output signal-to-noise ratio （SNR）, and overco.e the difficulty of traditional four-dimensional display. The theoretical analysis and simulation results both verify that this method can well enhance the spatial spectrum of line spectrum units, restrain the spatial spectrum of background noise units, and improve the performance of the broadband beam-forming.

关键词： information processing technology target detection broadband beam-forming main-to-side lobe ratio

Features of pipe transportation of paste-like backfilling in deep mine

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Journal of Central South University 2011年第5期18卷 1413-1417页

作者：王新民赵建文薛俊华余国锋 School of Resources and Safety Engineering Central South University Huainan mining (group) co. Ltd.

Based on the pipe transportation of paste-like backfilling system of a certain deep co.l mine,its dynamics process was simulated and analyzed.A two-dimensional dynamic model of extraordinary deep and lone pipe was built by GAMBIT,on the basis of which the simulation was done by implicit solver of FLUENT *** results show that hydraulic loss of pipe transportation is less than the pressure produced by gravity,which means the backfilling material can flow by *** the inlet velocity is 3.2 m/s,the maximum velocity of 4.10 m/s is at the elbow and the maximum velocity in the horizontal pipe is 3.91 m/s,which can both meet the stability *** results of the simulation are proved to be reliable by the residual monitor plotting of related parameter,so it can be co.cluded that the system of pipe transportation is safe.

关键词： backfilling deep mine paste-like slurry pipe transportation flow

Near-microsco.ic grain boundary facilitates fatigue crack propagation in a polycrystalline Al–Zn–Mg–Cu alloy

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Progress in Natural Science:Materials International 2023年第1期33卷 120-125页

作者： Kai Wen Xiwu Li Baiqing Xiong Haitao Lin Qinghong Wen Yanan Li Hongwei Yan Lizhen Yan Yongan Zhang Zhihui Li Hongwei Liu State Key Laboratory of Nonferrous Metals and Processes China GRINM Group Co. LTD. GRIMAT Engineering Institute co. LTD. General Research Institute for Nonferrous Metals Southwest Aluminum(group) co. Ltd.

In present study, grain characteristics with sizes within 10–30 μm were fabricated from a same Al–Zn–Mg–Cu alloy, FCP behaviors of the alloys with small grain(SG alloy), medium grain(MG alloy) and large grain(LG alloy)were investigated and related fatigue fracture morphology was analyzed. With the enhancement of stress intensity factor range(ΔK), the alloy with larger grains possessed faster FCP rate, which were successively arranged as SG alloy > MG alloy > LG alloy at initial stage while turned to LG alloy > MG alloy > SG alloy at final stage for the stable expanding region. Except for co.ventional characteristics of striations, tearing ridges, seco.dary cracks,seco.d phases, voids and dimples, more prominent grain boundary features appeared on fracture surface, especially for MG and LG alloy. The calculation of cyclic plastic zone(CPZ) sizes proved that grain boundary participated and promoted FCP behavior when CPZ co.ered grain and grain boundary together.

关键词： Fatigue crack propagation Grain size Grain boundary Cyclic plastic zone Al–Zn–Mg–Cu alloy

Mechanical properties of frozen rock mass with two diagonal intersected fractures

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International Journal of mining Science and Technology 2018年第4期28卷 626-633页

作者： Hao Yang Renliang Shan Jinxun Zhang Fumei Wu Zhiming Guo School of Mechanics and Civil Engineering China University of Mining & Technology Postdoctoral Workstation Beijing Urban Construction Group CO. Ltd.

Based on previous research results, this paper investigated the influence of fracture morphology on mechanical properties and failure modes of rock mass with two diagonal intersected fractures. This study carried out a series of triaxial co.pression tests on rock-like specimens with two crossed fractures under negative temperature, co.cluded the following co.clusions. The strength and failure modes of rock mass are significantly influenced by the dips of two crossed fractures. The strength of rock mass with two frac- tures cannot simply be estimated using the method that was developed for the rock mass with a single fracture. When the intersecting angle is less than 30~, the failure plane initiates at the tip of ＂artificial rup- tures＂ and extends to the upper and lower ends of the specimen. In case of a higher dip and intersecting angle ranging from 30° to 60°, the failure plane propagates along one of these two fractures. The mechan- lca! parameters of rock mass are not only related to the trace length, but also depend on the trace !ength ratio. One co.ld roughly calculate the strength parameters using the approximation proposed *** paper..For the rock mass with a trace length ratio 〈0.3 （short trace length/long trace length）, the failure mode is dependent on the fracture with a longer trace length. When the trace length beco.es significant and the trace length ratio approximates to 1, the failure plane propagates along two fractures, where an *** pattern is presented： For the rock mass with moderate frac!ures and a trace length ratio of approxlmately 1, the failure mode *** on fractures, which is simllar to .the damage pattern of intact rock. The strength, and elastic .modulus of rock mass decrease with the increase of spacing between fractures, whl!e Polsson＇s ratio is Independent on the spacing. The failure mode can be deter- mined by the area. of triangle created by two fractures. Damage occurs at the smaller triangle area first, an

关键词： Intersected fractures Fracture morphology Failure modes Mechanical properties

Preparation and characterization of layered low-voltage ZnO varistors

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Journal of Semico.ductors 2009年第3期30卷 19-22页

作者：王立惠甘国友孙加林严继康 Faculty of Materials and Metallurgical Engineering Kunming University of Science and Technology China Nonferrous Metal mining(group) co. Ltd.

Double-layered, low-voltage ZnO varistors have been fabricated by feeding two kinds of ZnO powders into a die using dry extrusion molding. co.pared with ZnO varistors fabricated by the co.ventional route, the layered ZnO varistors have larger non-linear co.fficients, lower breakdown electric fields, and lower leakage current densities. The improvement in electrical performance of the layered low-voltage ZnO varistors is attributed to the asymmetric band structure at grain boundary between the two layers.

关键词： layered ZnO varistor non-linearity electrical properties

Geological Characteristics and Ore-co.trolling Factors of the Beiya gold–Polymetallic Ore Deposit, Northwestern yunnan Province

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 1841-1861页

作者： ZHOU Yunman ZHANG Changqing HE Zhonghua LIU Huan ZHOU Guiwu SUN Jia LIU Bo yunnan gold & mining group co. ltd. Kunming 650224 China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China Beijing Research Institute of Uranium Geology Beijing 100029 China

Based on co.prehensive petrological, geochronological, and geochemical studies, this study analyzed the relationships between the Beiya gold-polymetallic skarn deposit and quartz syenite porphyries, and discussed the source（s） and evolution of magmas. Our results suggest that syenite porphyries（i.e. the Wandongshan, the Dashadi, and the Hongnitang porphyries）, which formed between the Eocene and the early Oligocene epochs, are the sources for the gold-polymetallic ores at the Beiya deposit. Carbonate rocks（T2 b） of the Triassic Beiya Formation in the ore district provide favorable host space for deposit formation. Fold and fault structures co.lectively play an important role in ore formation. The co.tact zone between the porphyries and carbonates, the structurally fractured zone of carbonate and clastic rocks, and the zone with well-developed fractures are the ideal locations for ore bodies. Four types of mineralization have been reco.nized： 1） porphyry-style stockwork gold–iron（co.per） ore, 2） skarn-style gold-iron（co.per and lead） ore in the near co.tact zone, 3） strata-bound, lense-type lead–silver–gold ore in the outer co.tact zone, and 4） distal vein-type gold–lead–silver ore. Supergene processes led to the formation of oxide ore, such as the weathered and accumulated gold–iron ore, the strata-bound fracture oxide ore, and the structure-co.trolled vein-type ore. Most of these ore deposits are distributed along the axis of the depressed basin, with the hypogene ore co.trolling the shape and characteristics of the oxide ore. This study provides critical geology understanding for mineral prospecting scenarios.

关键词： porphyry-skarn type quartz syenite porphyries ore-co.trolling factors Beiya goldpolymetallic deposit northwestern yunnan province

Enhanced efficiency of top-emission InP-based green quantum dot light-emitting diodes with optimized angular distribution

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Nano Research 2021年第11期14卷 4243-4249页

作者： Dong Li Jingwen Feng Youqin Zhu Zhigao Lu Chen Pei Zhuo Chen Yanzhao Li Xinguo Li Xiaoguang Xu BOE Technology group co. Ltd.Beijing100176China

High resolution and wide co.or gamut are two key requirements for novel display technologies. Owing to the distinguishing advantages over co.ventional displays, such as intrinsic wide co.or gamut and the possibility to achieve high resolution, quantum dot light-emitting diodes (QLED) have drawn co.siderable attention in recent years. On the other hand, indium phosphide quantum dots (InP QDs) have shown a great potential as a replacement for cadmium selenide (CdSe) QDs in display applications due to the inherent toxicity of cadmium-based QDs. In this study, we investigate a top-emission InP-based green QLED with optimized angular distribution. By adjusting the electrical and optical architecture, the device exhibits improved properties with a maximum current efficiency of 30.1 cd/A and a narrowed full width at half maxima (FWHM)of 31 nm, which are the best results ever reported to our knowledge.

关键词： Cd-free quantum dots quantum dot light-emitting diode(QLED) top-emission angular distribution current efficiency

Study on first caving fracture mechanism of overlying roof rock in steep thick co.l seam

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International Journal of mining Science and Technology 2015年第1期25卷 133-138页

作者： Zhang Bei Cao Shenggen State Key Laboratory of co.l Resources and Safe mining China University of Mining and Technology Shanxi Provincial Guoxin Energy Development group co. Ltd.

Based on the elastic plate theory, a mechanical model of thin plate for the first caving of overlying roof rock in steep mining face was established. The analytical solution of the deflection and stress distribution of roof rocks was obtained. Acco.ding to the specific geological co.ditions of the 5-103 panel in Shanxi,the failure of roof rocks and the influence of seam dip on it during the exploitation were theoretically investigated. Meanwhile, the first caving characteristics of the overlying rock in the steep co.l seam were investigated based on its stress co.tour. The results show that the dip angle has a distinct influence on the caving interval and the first caving interval for the 5-103 panel is 37 m in theory. Finally, a systematic monitoring on the behavior of rock pressures was co.ducted. The measured results agree well with the theoretical prediction, which provides a good reference for practical steep co.l seam mining.

关键词： Steepmining fieldInitial fracture intervalThin plate theoryco.l pressure monitoring

Technique of co.l mining and gas extraction without co.l pillar in multi-seam with low permeability

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Journal of co.l Science & Engineering(China) 2009年第2期15卷 120-128页

作者： YUAN Liang Huainan mining （group） co. ltd. Huainan 232001 China

Aimed at the low mining efficiency in deep multi-seams because of high crustalstress,high gas co.tent,low permeability,the co.pound 'three soft' roof and the trouble-somesafety situation enco.ntered in deep level co.l exploitation,proposed a new idea ofgob-side retaining without a co.l-pillar and Y-style ventilation in the first-mined key pressure-relieved co.l seam and a new method of co.l mining and gas *** followingwere disco.ered:the dynamic evolution law of the crannies in the roof is influenced bymining,the formative rule of 'the vertical cranny-abundant area' along the gob-side,thedistribution of air pressure field in the gob,and the flowing rule of pressure-relieved gas ina Y-style ventilation *** study also established a theoretic basis for a new miningmethod of co.l mining and gas extraction which is used to extract the pressure-relievedgas by roadway retaining boreholes instead of roadway *** and resolvedmany difficult key problems,such as,fast roadway retaining at the gob-side without a co.lpillar,Y-style ventilation and extraction of pressure-relieved gas by roadway retainingboreholes,and so *** study innovated and integrated a whole set of technical systemsfor co.l and pressure relief gas *** method of the pressure-relieved gasextraction by roadway retaining had been successfully applied in 6 typical working faces inthe Huainan and Huaibei mining *** research can provide a scientific and reliabletechnical support and a demonstration for co.l mining and gas extraction in gaseous deepmulti-seams with low permeability.

关键词： co.l seam with low permeability without co.l-pillar gob-side roadway retaining roadway retaining and borehole drilling co.l mining and gas extraction