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Geology and mineralization of the Hongqiling large magmatic nickel-copper-cobalt deposit(22×10^(4)t)in Jilin Province,China:A review
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作者 Cong Chen Yu-chao Gu +14 位作者 Di Zhang Tao-tao Wu Ai Li Yun-sheng Ren Qing-qing Shang Jian Zhang Xiong-fei Bian Fei Su Jia-lin Yang Qiu-shi Sun Xiao-hai Li Wan-zhen Liu Zhen-ming Sun Sen Zhang Yu-hui Feng 《China Geology》 CAS CSCD 2024年第4期762-796,共35页
The Hongqiling large nickel-copper-cobalt deposit(hereafter referred to as the Hongqiling deposit),a typical mafic-ultramafic copper-nickel deposit in China,boasts proven Ni(Ni)resources of approximately 22×10^(4... The Hongqiling large nickel-copper-cobalt deposit(hereafter referred to as the Hongqiling deposit),a typical mafic-ultramafic copper-nickel deposit in China,boasts proven Ni(Ni)resources of approximately 22×10^(4)t,associated copper resources of 2×10^(4)t,and associated cobalt(Co)resources of 0.5×10^(4)t,with Ni reserves ranking 10th among China's magmatic nickel deposits.Geotectonically,the Hongqiling deposit is situated in the superimposed zone between the Xing'an-Mongolian orogenic belt and the circum-Western Pacific's active continental margin belt.Its ore-bearing plutons occur within the metamorphic rocks of the Ordovician Hulan Group,with the emplacement of plutons and the locations of orebodies governed by the deep-seated Huifahe fault and its secondary NW-trending Fujia-Hejiagou-Beixinglong-Changsheng fault zone.In the deposit,the rock assemblages of ore-bearing plutons predominantly encompass gabbro-pyroxenite-olivine pyroxenite-pyroxene peridotite(pluton No.1)and norite-orthopyroxenite-harzburgite(pluton No.7),with ore-bearing lithofacies consisting primarily of olivine pyroxenite and pyroxenite facies.The Hongqiling deposit hosts stratoid,overhanging lentoid,veined,and pure-sulfide veined orebodies.Its ores principally contain metallic minerals including pyrrhotite,pentlandite,chalcopyrite,violarite,and pyrite.Despite unidentified magma sources of ore-bearing mafic-ultramafic rocks,it is roughly accepted that the magmatic evolution in the Hongqiling deposit primarily involved fractional crystallization and crustal contamination.The ore-forming materials were primarily derived from the upper mantle,mixed with minor crustal materials.The ore-bearing mafic-ultramafic rocks in the deposit,primarily emplaced during the Indosinian(208-239 Ma),were formed in an intense extension setting followed by the collisional orogeny between the North China Plate and the Songnen-Zhangguangcai Range Block during the Middle-Late Triassic.From the perspective of the metallogenic geological setting,surrounding rocks,ore-controlling structures,and rock assemblages,this study identified one favorable condition and seven significant indicators for prospecting for Hongqiling-type nickel deposits and developed a prospecting model of the Hongqiling deposit.These serve as valuable references for exploring similar nickel deposits in the region,as well as the deep parts and margins of the Hongqiling deposit. 展开更多
关键词 Nickel-copper-cobalt deposit Fractional crystallization Crustal contamination MAGMATIC MINERALIZATION Re-Os isotopic age Sulfur isotopic Metallogenic mode Prospecting model Western Pacific’s active continental margin Mineral exploration engineering Hongqiling Jilin
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The dilemma of the Jiaodong gold deposits: Are they unique? 被引量:126
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作者 Richard J.Goldfarb M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第2期139-153,共15页
The ca. 126e120 Ma Au deposits of the Jiaodong Peninsula, eastern China, define the country's largest gold province with an overall endowment estimated as&gt;3000 t Au. The vein and disseminated ores are hosted by N... The ca. 126e120 Ma Au deposits of the Jiaodong Peninsula, eastern China, define the country's largest gold province with an overall endowment estimated as&gt;3000 t Au. The vein and disseminated ores are hosted by NE-to NNE-trending brittle normal faults that parallel the margins of ca. 165e150 Ma, deeply emplaced, lower crustal melt granites. The deposits are sited along the faults for many tens of kilometers and the larger orebodies are associated with dilatational jogs. Country rocks to the granites are Pre-cambrian high-grade metamorphic rocks located on both sides of a Triassic suture between the North and South China blocks. During early Mesozoic convergent deformation, the ore-hosting structures developed as ductile thrust faults that were subsequently reactivated during Early Cretaceous "Yan-shanian"intracontinental extensional deformation and associated gold formation. 〈br〉 Classification of the gold deposits remains problematic. Many features resemble those typical of orogenic Au including the linear structural distribution of the deposits, mineralization style, ore and alteration assemblages, and ore fluid chemistry. However, Phanerozoic orogenic Au deposits are formed by prograde metamorphism of accreted oceanic rocks in Cordilleran-style orogens. The Jiaodong de-posits, in contrast, formed within two Precambrian blocks approximately 2 billion years after devolati-lization of the country rocks, and thus require a model that involves alternative fluid and metal sources for the ores. A widespread suite of ca. 130e123 Ma granodiorites overlaps temporally with the ores, but shows a poor spatial association with the deposits. Furthermore, the deposit distribution and mineral-ization style is atypical of ores formed from nearby magmas. The ore concentration requires fluid focusing during some type of sub-crustal thermal event, which could be broadly related to a combination of coeval lithospheric thinning, asthenospheric upwelling, paleo-Pacific plate subduction, and seismicity along the continental-scale Tan-Lu fault. Possible ore genesis scenarios include those where ore fluids were produced directly by the metamorphism of oceanic lithosphere and overlying sediment on the subducting paleo-Pacific slab, or by devolatilization of an enriched mantle wedge above the slab. Both the sulfur and gold could be sourced from either the oceanic sediments or the serpentinized mantle. A better understanding of the architecture of the paleo-Pacific slab during Early Cretaceous below the eastern margin of China is essential to determination of the validity of possible models. 展开更多
关键词 Gold Jiaodong North China block Tectonics Mineral deposit mode
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Organic/ Inorganic Occurrence of Metallic Elements of the Black Shale-Hosted Baiguoyuan Silver-Vanadium Deposit in Xingshan, Hubei 被引量:4
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作者 ZHUANG Hanping LU Jialan +4 位作者 FU Jiamo LIU Jinzhong REN Chigang ZOU Degang TIAN Weizhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第3期299-307,共9页
: By means of kerogen purification, the proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA), the authors have studied the organic/inorganic occurrence modes of the metallic element... : By means of kerogen purification, the proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA), the authors have studied the organic/inorganic occurrence modes of the metallic elements of the Baiguoyuan silver-vanadium deposit hosted in black shale in Hubei Province, China. The result shows that Au, Hg and Ta have a strong tendency to occur organically, with more than 70% of these elements being associated organically. Se, Ga, Ag and Hf are partly associated with organic matter, with more than 20% of them occurring organically. Compared with the above elements, Zn, Cu, As and Sb are weakly associated organically, and tend to be enriched in kerogen. However, Mn, Th, U, V, Co, Cr, AI, Fe and Sc usually occur inorganically. Of the rare earth elements (REE), La, Ce, Tb, Dy, Yb and Lu have stronger ability to be associated with organic matter than Sm and Eu. 展开更多
关键词 Baiguoyuan black shale-hosted silver-vanadium deposit organic matter metallic elements occurrence modes
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Optical sensors based on the NiPc-CoPc composite films deposited by drop casting and under the action of centrifugal force
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作者 Noshin Fatima Muhammad M Ahmed +2 位作者 Khasan S Karimov Zubair Ahmad Fahmi Fariq Muhammad 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期114-118,共5页
In this study, solution processed composite films of nickel phthalocyanine(NiPc) and cobalt phthalocyanine(CoPc)are deposited by drop casting and under centrifugal force. The films are deposited on surface-type in... In this study, solution processed composite films of nickel phthalocyanine(NiPc) and cobalt phthalocyanine(CoPc)are deposited by drop casting and under centrifugal force. The films are deposited on surface-type inter-digitated silver electrodes on ceramic alumina substrates. The effects of illumination on the impedance and capacitance of the NiPc–CoPc composite samples are investigated. The samples deposited under centrifugal force show better conductivity than the samples deposited by drop casting technique. In terms of impedance and capacitance sensitivities the samples fabricated under centrifugal force are more sensitive than the drop casting samples. The values of impedance sensitivity(Sz)are equal to(-1.83) MΩ·cm^2/mW and(-5.365) MΩ·cm^2/mW for the samples fabricated using drop casting and under centrifugal force, respectively. Similarly, the values of capacitance sensitivity(Sc) are equal to 0.083 pF·cm^2/mW and 0.185 pF·cm~2/mW for the samples fabricated by drop casting and under centrifugal force. The films deposited using the different procedures could potentially be viable for different operational modes(i.e., conductive or capacitive) of the optical sensors. Both experimental and simulated results are discussed. 展开更多
关键词 optical sensors capacitive mode impedance mode centrifugal deposition
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Influence of different soil properties on the failure behavior of deposit slope under earthquake after rainfall
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作者 YANG Bing HOU Jiang-rong +1 位作者 ZHOU Zi-hong GOU Jin-cheng 《Journal of Mountain Science》 SCIE CSCD 2023年第1期65-77,共13页
In this study,the influence of soil properties on the failure behavior and mechanism of slope under earthquake after rainfall was studied with shaking table test in the laboratory,in which the failure process of slope... In this study,the influence of soil properties on the failure behavior and mechanism of slope under earthquake after rainfall was studied with shaking table test in the laboratory,in which the failure process of slope and instant responses of water content and pore water pressure were tested.Based on the principle of similarity,a model test was designed.The experimental results showed that soil properties exhibit significant influence on failure mode and failure mechanism of slope.Local flowslide,local failure,and creep flowslide failure modes appear in the slope exposed to only rainfall.However,under earthquake after rainfall,the other three failure modes occur,i.e.,local slip failure,overall slip failure,and shallow scouring and creep flowslide failure.The spatial distribution of water content and pore water pressure are the two key factors leading to slope failure.Furthermore,due to the difference of permeability,the soil properties not only affect the spatial distribution of water content of the slope after rainfall,resulting in the peak pore water pressure which occurs mainly near the foot of the slope and near the bedrock interface in the middle and lower parts of the slope,but also affect the dissipation of excess pore water pressure in the process of earthquake.Finally,it is discovered that different types of soil lead to significant differences in the peak acceleration of slope failure.The critical acceleration of slope with coarse-grained soil is greater than that of slope with fine-grained soil.The critical acceleration of slope failure shows a close relationship with soil properties. 展开更多
关键词 Failure mode Failure mechanism deposit slope Soil properties Earthquake after rainfall
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GENERAL CHARACTER OF MULTISTAGES OFMETALLOGENESIS FOR MICRO-MESOTHERMAL GOLD DEPOSITS:EXAMPLES FROM ZHANG-BALING TECTONIC BELT,ANHUI,CHINA
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作者 DAI Ta-gen1,HUANG De-zhi1,QIU Rui-long2 ,XU Xiang2 (1.College of Resource,Environment and Civil Engineering,Central South University, Changsha 410 0 83,China 2 .Anhui Institute of Geological Sciences,H efei 2 30 0 0 1,China) 《Geotectonica et Metallogenia》 2001年第1期93-98,共6页
In Zhangbaling Tectonic Belt,two types of mineralization,auriferous quartz veins and alter- ation halos,can observed within many deposits.The pressure of metallogenesis of auriferous al- teration halos ismuch higher t... In Zhangbaling Tectonic Belt,two types of mineralization,auriferous quartz veins and alter- ation halos,can observed within many deposits.The pressure of metallogenesis of auriferous al- teration halos ismuch higher than thatof quartz vein,thetemperatures ofmetallogeneses ofthese two types of orebodies are don’tthe same Geochemistry study indicates thatboth ofthem are mi- cro- mesothermal deposits related to Yanshanian granites.The results of proton microprobe analy- sis of sulphides from the gold deposits in the area show that the“invisible” gold existed in sul- phides is in the form ofmicro inclusions,and the concentration of“invisible” gold in sulphidemin- erals within quartz vein is poorerthan thatfrom alteration halos.Field observation shows thatthe structural modality of the fractures controlling the orebodies of auriferous quartz vein is different from thatof the auriferous alteration zones.The fracture controlling the orebodies of auriferous alteration halos is compress- shearfracture,auriferous quartzvein is controlled by extensive fault. The alteration halos crosscut by auriferous quartz vein.The wallrocks of the former altered strongly and developed alteration zones well.The wallrocks of auriferous quartz vein altered slightly.The results of tectonogeochemical study shows that the concentration of associated met- allogenesis elements and intensity of alteration are positively correlated with tectonic deformation strength for auriferous alteration halos.Itindicates that it is probably a general character for mi- cro- mesothermal gold deposits due to the multistages of metallogeneses took place.The tectonic environmentis the most important fact determining the mechanism of fluid flow and precipitationof gold,and then the types of mineralization and modes of gold. 展开更多
关键词 Micro-mesothermal GOLD depositS modes of GOLD multistages of metallogeneses TECTONIC environment
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Identification of the anomaly component using BEMD combined with PCA from element concentrations in the Tengchong tin belt, SW China 被引量:7
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作者 Yongqing Chen Lina Zhang Binbin Zhao 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1561-1576,共16页
Concentration of elements or element groups in a geological body is the result of multiple stages of rockforming and ore-forming geological processes.An ore-forming element group can be identified by PCA(principal com... Concentration of elements or element groups in a geological body is the result of multiple stages of rockforming and ore-forming geological processes.An ore-forming element group can be identified by PCA(principal component analysis)and be separated into two components using BEMD(bi-dimensional empirical mode decomposition):(1)a high background component which represents the ore-forming background developed in rocks through various geological processes favorable for mineralization(i.e.magmatism,sedimentation and/or metamorphism);(2)the anomaly component which reflects the oreforming anomaly that is overprinted on the high background component developed during mineralization.Anomaly components are used to identify ore-finding targets more effectively than ore-forming element groups.Three steps of data analytical procedures are described in this paper;firstly,the application of PCA to establish the ore-forming element group;secondly,using BEMD on the o re-forming element group to identify the anomaly components created by different types of mineralization processes;and finally,identifying ore-finding targets based on the anomaly components.This method is applied to the Tengchong tin-polymetallic belt to delineate ore-finding targets,where four targets for Sn(W)and three targets for Pb-Zn-Ag-Fe polymetallic mineralization are identified and defined as new areas for further prospecting.It is shown that BEMD combined with PCA can be applied not only in extracting the anomaly component for delineating the ore-finding target,but also in extracting the residual component for identifying its high background zone favorable for mineralization from its oreforming element group. 展开更多
关键词 Bi-dimensional empirical mode decomposition(BEMD) Principal COMPONENT analysis(PCA) ANOMALY components ORE-FORMING ELEMENT groups Sn(W)and Pb-Zn-Ag-Fe POLYMETALLIC deposits Tengchong tin-polymetallic BELT
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Characteristics and advantages of energy performance contracting mode for energy saving transformation of existing large public building
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作者 GUO Han-ding ZHANG Hai-yun +1 位作者 XU Zhen-yan ZHANG Yin-xian 《Ecological Economy》 2016年第1期79-85,共7页
Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large ... Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large public buildings energy-saving is an effective way both at home and abroad. EPC mode has obvious characteristics for the ESCO and the customers, it can meet the basic requirements of large public buildings energy-saving, such as the width of funding sources, program specifi cation, advanced technology, information fl ow and management level higher, etc. Under the condition of market economy, it also provides a broad platform for the ESCO implements building energy saving transformation, which is conducive to the realization of the win-win cooperation between the parties, and to promote the healthy development of the existing large public building energy saving reconstruction. 展开更多
关键词 existing large PUBLIC building ENERGY SAVING transformation ENERGY performance contractING mode CHARACTERISTICS advantages
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Metallogenic origin of Sipingshan hot spring gold deposit in Hulin of Heilongjiang and its metallogenic mode
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作者 HUANG Yongwei LIU Jiajun +1 位作者 QUAN Chuanshun ZHU Wenfeng 《Global Geology》 2011年第2期73-86,共14页
Sipingshan gold deposit is gold-bearing sillcalite in type. There only exist a few kinds of sulfide in the ore and it is lower in content. The gold degree is lower. Au is closely related to the Ag, Cu, Pb, As and Hg e... Sipingshan gold deposit is gold-bearing sillcalite in type. There only exist a few kinds of sulfide in the ore and it is lower in content. The gold degree is lower. Au is closely related to the Ag, Cu, Pb, As and Hg elements. The upper sillealite has Eu and Ce negative anomaly, and the lower sillealite has Eu positive anomaly, however, the hot spring cemented breccia and rhyolite porphyry have Eu negative anomaly; the S isotope component has deep-seated magmatic sulfur and terrestrial sulfate characteristic; and the Ph isotope has the character of the mixture origin of crust and mantle that is mainly dominated by Pb in the orogenic beh. The oreforming tluid temperature is 180℃-244℃ , characterized by magmatie hydrothermal and meteoric water; and the ore-forming age is 87 Ma. The deposit was formed by the metallogenic fluid in the tectonic fault zone overtlowing near the earth' s surface and leading to the metallogenic funetion and the metallogenic substar,ee deposition. 展开更多
关键词 hot spring epithermal gold deposit substanee origin metallogenic mode Sipingshan Heilongjiang
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Geochemical Characteristics and Significance of Major Elements, Trace Elements and REE in Mineralized Altered Rocks of Large-Scale Tsagaan Suvarga Cu-Mo Porphyry Deposit in Mongolia 被引量:3
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作者 方维萱 杨社锋 +2 位作者 刘正桃 韦星林 张宝琛 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第6期759-769,共11页
The alteration types of the large-scale Tsagaan Suvarga Cu-Mo porphyry deposit mostly comprise stockwork silicification, argillization, quartz-sericite alteration, K-silicate alteration, and propylitization. The miner... The alteration types of the large-scale Tsagaan Suvarga Cu-Mo porphyry deposit mostly comprise stockwork silicification, argillization, quartz-sericite alteration, K-silicate alteration, and propylitization. The mineralized and altered zones from hydrothermal metallogenic center to the outside successively are Cu-bearing stockwork silicification zone, Cu-beating argillized zone, Cu-Mo-bearing quartz-sericite alteration zone, Cu-Mo-bearing K-silicate alteration zone, and pro- pylitization zone. The K-silicate alteration occurred in the early phase, quartz-sericite alteration in the medium phase, and argillization and carbonatization (calcite) in the later phase. Ore-bearing-altered rocks are significantly controlled by the structure and fissure zones of different scales, and NE- and NW-trending fissure zones could probably be the migration pathways of the porphyry hydrothermal system. Results in this study indicated that the less the concentrations of REE, LREE, and HREE and the more the extensive fractionation between LREE and HREE, the closer it is to the center circulatory hydrothermal ore-forming and the more extensive silicification. The exponential relationship between the fractionation of LREE and HREE and the intensity of silicification and K-silicate alteration was found in the Cu-Mo deposit studied. The negative Eu anomaly, normal Eu, positive Eu anomaly and obviously positive Eu anomaly are coincident with the enhancement of Na2O and K2O concentrations gradually, which indicated that Eu anomaly would be significantly controlled by the alkaline metasomatism of the circulatory hydrothermal ore-forming system. Therefore, such characteristics as the positive Eu anomaly, the obvious fractionation between LREE and HREE and their related special alteration lithofacies are suggested to be metallogenic prognostic and exploration indications for Tsagaan Suvarga-style porphyry Cu-Mo deposits in Mongolia and China. 展开更多
关键词 mongolia tsagaan suvarga porphyry Cu-Mo deposit wall rock alteration fractionation mode positive Eu anomaly rare earths
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A Study of Occurrences of Ag in Pb-Zn-Cu Ore Deposits in China 被引量:2
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作者 WANG Jingchun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期516-520,共5页
A systematic study of occurrences of silver in 156 Pb-Zn-Cu ore deposits indicates that silver mainly occurs in nonferrous metal ore deposits in forms of association and paragenesis. It occurs mainly as independent mi... A systematic study of occurrences of silver in 156 Pb-Zn-Cu ore deposits indicates that silver mainly occurs in nonferrous metal ore deposits in forms of association and paragenesis. It occurs mainly as independent minerals in nature and occasionally as ion adsorption, isomorphous or amorphous silver minerals. Nearly 190 silver minerals have been discovered in China. Their shapes, constituents, textures, grain sizes, embedded types, distribution patterns, mineral assemblages and metallogenic series suggest that these characteristics are closely related to geneses of deposits and dependent of ore-forming conditions. Pb, Zn and Cu sulphides are the main carrier minerals of silver. The partition of silver in ore is constrained by the mineralization intensity, grain size and embedded form of silver minerals and mineral assemblages. 展开更多
关键词 Pb-Zn-Cu ore deposit SILVER occurrence mode embedded type partitioning
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Construction of a 3D meso-structure and analysis of mechanical properties for deposit body medium 被引量:1
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作者 石崇 陈凯华 +3 位作者 徐卫亚 张海龙 王海礼 王盛年 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期270-279,共10页
For deposit body medium, the internal structural properties may be the controlling factors for the strength of the material and the mechanical response. Based on the results of soil-rock meso-statistics using digital ... For deposit body medium, the internal structural properties may be the controlling factors for the strength of the material and the mechanical response. Based on the results of soil-rock meso-statistics using digital imaging, a simulated annealing algorithm is adopted to expand the meso-structural features of deposit bodies in 3D. The construction of the 3D meso-structure of a deposit body is achieved, and then the particle flow analysis program PFC3 D is used to simulate the mechanical properties of the deposit body. It is shown that with a combination of the simulated annealing algorithm and the statistical feature functions, the randomness and heterogeneity of the rock distribution in the 3D inner structure of deposit body medium can be realized, and the reconstructed structural features of the deposit medium can match the features of the digital images well. The spatial utilizations and the compacting effects of the body-centered cubic, hexagonal close and face-centered packing models are high, so these structures can be applied in the simulations of the deposit structures. However, the shear features of the deposit medium vary depending on the different model constructive modes. Rocks, which are the backbone of the deposit, are the factors that determine the shear strength and deformation modulus of the deposit body. The modeling method proposed is useful for the construction of 3D meso-scope models from 2D meso-scope statistics and can be used for studying the mechanical properties of mixed media, such as deposit bodies. 展开更多
关键词 deposit body mesomechanical mode model continuation simulated annealing algorithm granular flow method
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Growth and characterization of AlN epilayers using pulsed metal organic chemical vapor deposition
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作者 吉泽生 汪连山 +5 位作者 赵桂娟 孟钰淋 李方政 李辉杰 杨少延 王占国 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期420-425,共6页
We report the growth of Al N epilayers on c-plane sapphire substrates by pulsed metal organic chemical vapor deposition(MOCVD). The sources of trimethylaluminium(TMAl) and ammonia were pulse introduced into the re... We report the growth of Al N epilayers on c-plane sapphire substrates by pulsed metal organic chemical vapor deposition(MOCVD). The sources of trimethylaluminium(TMAl) and ammonia were pulse introduced into the reactor to avoid the occurrence of the parasitic reaction. Through adjusting the duty cycle ratio of TMAl to ammonia from 0.8 to 3.0, the growth rate of Al N epilayers could be controlled in the range of 0.24 m/h to 0.93 m/h. The high-resolution x-ray diffraction(HRXRD) measurement showed that the full width at half maximum(FWHM) of the(0002) and(10-12) reflections for a sample would be 194 arcsec and 421 arcsec, respectively. The step-flow growth mode was observed in the sample with the atomic level flat surface steps, in which a root-mean-square(RMS) roughness was lower to 0.2 nm as tested by atomic force microscope(AFM). The growth process of Al N epilayers was discussed in terms of crystalline quality, surface morphology,and residual stress. 展开更多
关键词 pulsed metal organic chemical vapor deposition growth mode MORPHOLOGY crystalline quality
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Research of Current Mode Atomic Force Microscopy (C-AFM) for Si/SiC Heterostructures on 6H-SiC(0001)
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作者 Song Feng Lixun Song +2 位作者 Yuan Zang Zheyan Tu Lianbi Li 《Journal of Beijing Institute of Technology》 EI CAS 2020年第2期184-189,共6页
Si/SiC heterostructures with different growth temperatures were prepared on 6 HSiC(0001)by LPCVD.Current mode atomic force microscopy and transmission electron microscopy were employed to investigate the electrical pr... Si/SiC heterostructures with different growth temperatures were prepared on 6 HSiC(0001)by LPCVD.Current mode atomic force microscopy and transmission electron microscopy were employed to investigate the electrical properties and crystalline structure of Si/SiC heterostructures.Face-centered cubic(FCC)on hexagonal close-packing(HCP)epitaxy of the Si(111)/SiC(0001)heterostructure was realized at 900°C.As the growth temperature increases to1050°C,the<110>preferred orientation of the Si film is observed.The Si films on 6 H-SiC(0001)with different growth orientations consist of different distinctive crystalline grains:quasi-spherical grains with a general size of 20μm,and columnar grains with a typical size of 7μm×20μm.The electrical properties are greatly influenced by the grain structures.The Si film with<110>orientation on SiC(0001)consists of columnar grains,which is more suitable for the fabrication of Si/SiC devices due to its low current fluctuation and relatively uniform current distribution. 展开更多
关键词 Si/6H-SiC heterostructure electrical properties current mode AFM chemical vapor deposition
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Effect of a negative DC bias on a capacitively coupled Ar plasma operated at different radiofrequency voltages and gas pressures
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作者 相垚君 王晓坤 +1 位作者 刘永新 王友年 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期62-71,共10页
The effect of a negative DC bias,|V_(dc)|,on the electrical parameters and discharge mode is investigated experimentally in a radiofrequency(RF)capacitively coupled Ar plasma operated at different RF voltage amplitude... The effect of a negative DC bias,|V_(dc)|,on the electrical parameters and discharge mode is investigated experimentally in a radiofrequency(RF)capacitively coupled Ar plasma operated at different RF voltage amplitudes and gas pressures.The electron density is measured using a hairpin probe and the spatio-temporal distribution of the electron-impact excitation rate is determined by phase-resolved optical emission spectroscopy.The electrical parameters are obtained based on the waveforms of the electrode voltage and plasma current measured by a voltage probe and a current probe.It was found that at a low|V_(dc)|,i.e.inα-mode,the electron density and RF current decline with increasing|V_(dc)|;meanwhile,the plasma impedance becomes more capacitive due to a widened sheath.Therefore,RF power deposition is suppressed.When|V_(dc)|exceeds a certain value,the plasma changes toα–γhybrid mode(or the discharge becomes dominated by theγ-mode),manifesting a drastically growing electron density and a moderately increasing RF current.Meanwhile,the plasma impedance becomes more resistive,so RF power deposition is enhanced with|V_(dc)|.We also found that the electrical parameters show similar dependence on|V_(dc)|at different RF voltages,andα–γmode transition occurs at a lower|V_(dc)|at a higher RF voltage.By increasing the pressure,plasma impedance becomes more resistive,so RF power deposition and electron density are enhanced.In particular,theα–γmode transition tends to occur at a lower|V_(dc)|with increase in pressure. 展开更多
关键词 RF capacitively coupled plasma DC-overlapped RF discharge power deposition discharge mode transition
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Yb-doped passively mode-locked fiber laser with Bi_2Te_3-deposited
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作者 李璐 闫培光 +3 位作者 王勇刚 段利娜 孙航 司金海 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期329-333,共5页
In this study we present an all-normal-dispersion Yb-doped fiber laser passively mode-locked with topological insulator(Bi2Te3) saturable absorber. The saturable absorber device is fabricated by depositing Bi2Te3 on... In this study we present an all-normal-dispersion Yb-doped fiber laser passively mode-locked with topological insulator(Bi2Te3) saturable absorber. The saturable absorber device is fabricated by depositing Bi2Te3 on a tapered fiber through using pulsed laser deposition(PLD) technology, which can give rise to less non-saturable losses than most of the solution processing methods. Owing to the long interaction length, Bi2Te3 is not exposed to high optical power, which allows the saturable absorber device to work in a high power regime. The modulation depth of this kind of saturable absorber is measured to be 10%. By combining the saturable absorber device with Yb-doped fiber laser, a mode-locked pulse operating at a repetition rate of 19.8 MHz is achieved. The 3-d B spectral width and pulse duration are measured to be 1.245 nm and317 ps, respectively. 展开更多
关键词 topological insulator mode-locked lasers pulsed laser deposition technology fiber lasers
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公路工程设计施工总承包模式研究
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作者 黄雨婷 《中国厨卫》 2025年第1期302-304,共3页
公路工程设计施工总承包模式(EPC模式),在提升项目管理效率和控制成本方面具有显著优势,但在实际应用中仍存在诸多问题。为进一步提升项目的管理效率,文章首先阐述了EPC模式,并指出其在当前应用中的优势和不足之处;接着,详细探讨了管理... 公路工程设计施工总承包模式(EPC模式),在提升项目管理效率和控制成本方面具有显著优势,但在实际应用中仍存在诸多问题。为进一步提升项目的管理效率,文章首先阐述了EPC模式,并指出其在当前应用中的优势和不足之处;接着,详细探讨了管理机制不健全、设计与施工衔接不畅等主要问题;最后,提出了完善管理机制、加强设计与施工衔接、完善风险管理体系等措施,以期为公路工程设计施工总承包模式的进一步发展提供参考。 展开更多
关键词 公路工程 施工总承包模式 项目管理
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Geochemical characteristics of the independent cadmium deposit, Niujiaotang, Duyun, Guizhou 被引量:2
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作者 LIU Tiegeng~1, YE Lin~1 and CHEN Guoyong~2 1. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. Team No. 104, Bureau of Geology and Mineral Resources, Duyun, Guizhou 558000, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S2期61-63,共3页
A large independent cadmium deposit has been found at Niujiaotang, Duyun, in recent years. To the bestof our knowledge this represents the first case of its kind in the world. With a reserve of over 5 000 tonsof cadmi... A large independent cadmium deposit has been found at Niujiaotang, Duyun, in recent years. To the bestof our knowledge this represents the first case of its kind in the world. With a reserve of over 5 000 tonsof cadmium, the deposit is unique in its high concentrations of cadmium which are tens of to over onehundred times higher than in ordinary cadmium mineralizations associated with Pb-Zn deposits. 1 Geological characteristics The Niujiaotang deposit is located at the southwest margin of the Yangtze Plate. The region consistsof a thick sedimentary cover ranging from Sinian to Triassic in age overlying unconformably the basementof Mid-Proterozoic metamorphosed volcanic-sedimentary rocks. Lower Cambrian carbonate strata arcoutcropped in the mining district. Cadmium mineralizations, with seven layers recognizable, are devel- 展开更多
关键词 INDEPENDENT CADMIUM deposit mode of occurrence of CADMIUM inclusion fluid feature stable ISOTOPE geochemistry.
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Research on two-part revenue-sharing contract under demand disruption
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作者 侯晶 赵林度 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期57-63,共7页
Assuming that the realized demand is determined by the inventory level,a two-part revenue sharing contract of one supplier and one retailer is analyzed under the circumstance of demand disruption(the disruption cost o... Assuming that the realized demand is determined by the inventory level,a two-part revenue sharing contract of one supplier and one retailer is analyzed under the circumstance of demand disruption(the disruption cost occurs at the supplier).Based on the centralized optimization,the profits of the two members are maximized in sequential optimization though a two-part revenue-sharing contract.The result shows that when the demand disruption occurs,if the degree of disruption is within some range,the ordering and manufacturing plans need not be changed,while only the revenue sharing fraction for the retailer should be diminished;if not,both the plan and the revenue sharing fraction should be changed for the possible coordination of the supply chain.Finally,numerical illustrations of the contract for various scenarios are given. 展开更多
关键词 logistics service mode supply chain coordination revenue-sharing contract demand disruption
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Unveiling the origin of anomalous low-frequency Raman mode in CVD-grown monolayer WS_(2) 被引量:2
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作者 Qian Xiang Xiaofei Yue +8 位作者 Yanlong Wang Bin Du Jiajun Chen Shaoqian Zhang Gang Li Chunxiao Cong Ting Yu Qingwei Li Yuqi Jin 《Nano Research》 SCIE EI CSCD 2021年第11期4314-4320,共7页
Substrates provide the necessary support for scientific explorations of numerous promising features and exciting potential applications in two-dimensional (2D) transition metal dichalcogenides (TMDs). To utilize subst... Substrates provide the necessary support for scientific explorations of numerous promising features and exciting potential applications in two-dimensional (2D) transition metal dichalcogenides (TMDs). To utilize substrate engineering to alter the properties of 2D TMDs and avoid introducing unwanted adverse effects, various experimental techniques, such as high-frequency Raman spectroscopy, have been used to understand the interactions between 2D TMDs and substrates. However, sample-substrate interaction in 2D TMDs is not yet fully understood due to the lack of systematic studies by techniques that are sensitive to 2D TMD-substrate interaction. This work systematically investigates the interaction between tungsten disulfide (WS_(2)) monolayers and substrates by low-frequency Raman spectroscopy, which is very sensitive to WS_(2)-substrate interaction. Strong coupling with substrates is clearly revealed in chemical vapor deposition (CVD)-grown monolayer WS_(2) by its low-wavenumber interface mode. It is demonstrated that the enhanced sample-substrate interaction leads to tensile strain on monolayer WS_(2), which is induced during the cooling process of CVD growth and could be released for monolayer WS_(2) sample after transfer or fabricated by an annealing-free method such as mechanical exfoliation. These results not only suggest the effectiveness of low-frequency Raman spectroscopy for probing sample-substrate interactions in 2D TMDs, but also provide guidance for the design of high-performance devices with the desired sample-substrate coupling strength based on 2D TMDs. 展开更多
关键词 interface mode monolayer tungsten disulfide low-frequency Raman spectroscopy sample-substrate interaction strain chemical vapor deposition
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