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Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review

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China Geology 2024年第3期7卷 533-550页

作者： Shi-min Zhen Da-zhao Wang Zhong-jian Zha Hai-jun Bai Jiang Wang Development and research Center of China Geological Survey Ministry of Natural ResourcesBeijing 100037China Technical Guidance Center for Mineral Resources Exploration Ministry of Natural ResourcesBeijing 100037China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China institute of Geological Surveying and Mapping Technology of Anhui Province Hefei 230022China Third Geological Brigade of Hebei Bureau of Geology and Mineral Resources Zhangjiakou 075000China Ulanqab Real Estate Registration Center Ulanqab 012099China

The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of *** paper presents a new understanding for Dongping ore system,based on the previous *** mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the *** compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou ***-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage *** systematic changes are closely related to the processes of mineral precipitation and fluid *** precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur *** of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-ag minerals and native *** on these hypotheses,this paper present a polyphase metallogenic model as *** the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early *** the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.

关键词： Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton Mineral exploration engineering

Precision phenotyping of contrasting potato(Solanum tuberosum L.) varieties in a novel aeroponics system for improving nitrogen use efficiency: In search of key traits and genes

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Journal of Integrative agriculture 2020年第1期19卷 51-61页

作者： Jagesh K.TIWARI Sapna DEVI Tanuja BUCKSETH Nilofer ALI Rajesh K.SINGH Rasna ZINTA Vijay K.DUA Swarup K.CHAKRABARTI Indian Council of agricultural research-Central Potato research institute

With increasing population, degrading soil health, limited arable land area, and high cost of nitrogen(N) fertilizers, improving nitrogen use efficiency(NUE) of potato is an inevitable approach to save the environment and achieve sufficient tuber yields with less N fertilizer supply. Recently, we have developed an aeroponics system to study NUE in potato using genomics, physiology, and breeding approaches. This study aims on precision phenotyping of plants of two distinct potato varieties(Kufri Gaurav, N efficient;Kufri Jyoti, N inefficient) in the novel aeroponics system. Plants were grown in aeroponics under controlled conditions with low N(0.75 mmol L^-1NO3^-) and high N(7.5 mmol L^-1NO3^-) levels. Plant biomass, root traits, total chlorophyll content, and plant N were increased with increasing N supply, whereas higher NUE parameters namely NUE, agronomic NUE(ag NUE), N uptake efficiency(NUp E), harvest index(HI), and N harvest index(NHI) were observed at low N. An NUE efficient cv. Kufri Gaurav showed higher tuber dry weight, fresh tuber yield, tuber number per plant, early start of tuber harvesting, root traits, stolon traits, NUE parameters, and higher amino acid(aspartic acid and asparagine) content at low N supply. Higher expression of nitrate reductase(NR), nitrite reductase(NIR), and asparagine synthetase(AS) genes was observed in the leaf tissues of Kufri Gaurav at high N. Thus, aeroponics-based precision phenotyping enables identification of NUE efficient genotypes based on key traits and genes involved in improving NUE in potato. Further, this study suggests that the potential of aeroponics can be utilized to investigate N biology in potato under different N regimes.

关键词： aeroponics precision phenotyping potato nitrogen use efficiency

A Tailor-made Data Quality Approach for Higher Educational Data

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Journal of Data and Information Science 2020年第3期5卷 129-160页

作者： Cinzia Daraio Renato Bruni Giuseppe Catalano Alessandro Daraio Giorgio Matteucci Monica Scannapieco Daniel Wagner-Schuster Benedetto Lepori DI ag Sapienza University of RomeItaly Italian National institute of Statistics Italy JOANNEUM research Institute for Economic and Innovation ResearchAustria Universita della Svizzera italiana Faculty of Communication sciencesSwitzerland

Purpose: This paper relates the definition of data quality procedures for knowledge organizations such as Higher Education Institutions. The main purpose is to present the flexible approach developed for monitoring the data quality of the European Tertiary Education Register(ETER) database, illustrating its functioning and highlighting the main challenges that still have to be faced in this ***/methodology/approach: The proposed data quality methodology is based on two kinds of checks, one to assess the consistency of cross-sectional data and the other to evaluate the stability of multiannual data. This methodology has an operational and empirical orientation. This means that the proposed checks do not assume any theoretical distribution for the determination of the threshold parameters that identify potential outliers, inconsistencies, and errors in the data. Findings: We show that the proposed cross-sectional checks and multiannual checks are helpful to identify outliers, extreme observations and to detect ontological inconsistencies not described in the available meta-data. For this reason, they may be a useful complement to integrate the processing of the available *** limitations: The coverage of the study is limited to European Higher Education Institutions. The cross-sectional and multiannual checks are not yet completely *** implications: The consideration of the quality of the available data and information is important to enhance data quality-aware empirical investigations, highlighting problems, and areas where to invest for improving the coverage and interoperability of data in future data collection ***/value: The data-driven quality checks proposed in this paper may be useful as a reference for building and monitoring the data quality of new databases or of existing databases available for other countries or systems characterized by high heterogeneity and complexity of the units of analysi

关键词： Knowledge organization Development of data and information services Cross-sectional and multiannual quality checks Higher education institutions Information quality

Towards rational design in electrochemical denitrification by analyzing pH dependence

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National Science Review 2024年第06期 223-232页

作者： Huan Li Dong Luan Jun Long Xiaoyan Fu Jianping Xiao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

A small fraction of NOx（<1%） always exists in CO2feedstock（e.g. exhausted gas）, which can significantly reduce the efficiency of CO2electroreduction by ～30%. Hence, electrochemical denitrification is the precondi...

A small fraction of NOx（ag）, partial pressures（20%, 50% and100%） and potentials（from -0.2 to 0.2 V vs. reversible hydrogen electrode）. All in all, the insights herein overturn long-lasting views in the field of NO electroreduction and suggest that rational design should steer away from catalyst engineering toward reactor optimization.

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Ultra-homogeneous dense ag nano layer enables long lifespan solid-state lithium metal batteries

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Journal of Energy Chemistry 2024年第9期96卷 110-119页

作者： Yaning Liu Tianqi Yang Ruyi Fang Chengwei Lu Ruojian Ma Ke Yue Zhen Xiao Xiaozheng Zhou Wenkui Zhang Xinping He Yongping Gan Jun Zhang Xinhui Xia Hui Huang Xinyong Tao Yang Xia College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014ZhejiangChina Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesChina Jiliang UniversityHangzhou 310018ZhejiangChina

The unstable electrolyte/lithium(Li)anode interface has been one of the key challenges in realizing high energy density solid-state lithium metal batteries(LMBs)***,a dense and uniform silver(ag)nano interlayer with a thickness of∼35 nm is designed accurately by magnetron sputtering technology to optimize the electrolyte/Li anode *** ag nano layer reacts with Li metal anode to in-situ form Li-ag alloy,thus enhancing the physical interfacial contact,and further improving the interfacial wettability and *** particular,the Li-ag alloy is inclined to form agLi phase proved by cryo-TEM and DFT,effectively preventing SN from continuously“attacking”the Li metal anode due to the lower adsorption of succinonitrile(SN)molecules on agLi than that of pure Li metal,thereby significantly reinforcing the interfacial ***,the enhanced physical and chemical stability of electrolyte/Li anode interface promotes the homogeneous deposition of Li^(+)and inhibits the dendrite *** Li-symmetric cell maintains stable operation for up to 1700 h and the cycling stability of LiFePO_(4)|SPE|Li full cell is remarkably improved at room temperature(capacity retention rate of 91.9%for 200 cycles).This work opens an effective way for accurate and controllable interface design of long lifespan solid-state LMBs.

关键词： Silvernano layer Poly(ethylene oxide) Solid polymer electrolyte Succinonitrile Lithium metal battery

Reduction of dinitrogen to ammonia on doped three-atom clusters Nb_(2)M(M=Sc to Cu & Y to ag)

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Rare Metals 2024年第8期43卷 3810-3818页

作者： Ran Cheng Chao-Nan Cui Zhi-Xun Luo Beijing National Laboratory for Molecular Science(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy ***-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active *** a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to ag) clusters was *** key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic *** d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was *** examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these *** work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.

关键词： Three-atom cluster catalysis Three-criteria strategy Nitrogen fixation Ammonia synthesis Theoretical calculations

Effect of Au film pre-deposited at different durations as inner electrode on the electrical properties and interface microstructures of Na_2O-PbO-Nb_2O_5-SiO_2 multi-layer glass-ceramic capacitors

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Acta Metallurgica Sinica(English Letters) 2011年第6期24卷 449-456页

作者： Jun ZHU Jun LUO Qingmeng ZHANG Jun DU Advanced Electronic Materials institute General Research Institute for Nonferrous Metals Beijing 100088 China

To further study the effect of sputtered Au film as transition electrode layer on the electrical properties and interface microstructures of Na20-PbO-Nb2O5-SiO2 multilayer glass-ceramic capacitors, Au films pre-deposited at different time were prepared by DC magnetron sputtering. Compared with the single paste electrode structure, samples with Au films pre-deposited from 6 to 18 min have the consistent perfor- mance to effectively improve the electrical properties of the capacitors, resulting in the doubled breakdown strength, an increase of equivalent capacitance by 22% and a decrease of leakage current by an order of magnitude. SEM observations indicate that the Au films with deposition time from 6 to 18 min would all help the formation of a dense electrode/dielectric interface and inhibit the diffusion of ag. The results reveal that Au film pre-deposited for 6 min as inner electrode was sufficient to improve the interface microstructure and therefore to inhibit the ag diffusion and enhance the overall performance of the multi-layer glass-ceramic capacitors.

关键词： Inner electrode Deposition time Glass-ceramic Multi-layer capacitor

The relationship between formate adsorption energy and electronic properties: A first principles density functional theory study

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Science China Chemistry 2009年第9期52卷 1427-1433页

作者： MORIKAWA Yoshitada NAKAMURA Junji The institute of Scientific and Industrial research (ISIR) Osaka University research institute for Computational Sciences (RICS) National Institute of Advanced Industrial Science and Technology (AIST) institute of Materials Science University of Tsukuba

First principles density functional theory calculations have been performed for the chemisorption of formate adsorption on some metal surfaces. For the most stable adsorption site of short-bridge, the calculated formate adsorption energy follows the order of Au(110) ag(110) < Cu(110) < Pd(110) < Pt(110) < Ni(110) < Rh(110) < Fe(100) < Mo(100), and a clear linear correlation exists between the adsorption energy and the corresponding heat of formation of metal oxides. Moreover, it has been found that the formate adsorption energy for the transition metals can be correlated well with its d-band center (εd), and the IB Group metals can be described by the coupling matrix element square (Vad2).

关键词： formate metal DFT-GGA slab model adsorption energy d-band center

氧化石墨烯包埋普鲁士蓝复合物的高效电容去离子和水消毒研究

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Science China Materials 2024年第1期67卷 143-152页

作者：李南任攀宇田苗王科 Atif Saleem 刘念余骆峰李鹏 Frontiers Science Center for Flexible Electronics(FSCFE) Xi’an Institute of Flexible Electronics(IFE)and Xi’an Institute of Biomedical Materials&Engineering(IBME)Northwestern Polytechnical University(NPU)Xi’an 710072China School of Ecology and Environment Northwestern Polytechnical University(NPU)Xi’an 710072China

具有除菌性能的电容去离子材料对于制备高效节能同时具备脱盐和抗微生物污染功能的电极材料至关重要,然而由于双电层电吸附机制的影响,多数碳基材料的吸附容量受到限制.同时,近年来部分研究学者通过对电极材料进行抗菌化合物的修饰并用... 详细信息

具有除菌性能的电容去离子材料对于制备高效节能同时具备脱盐和抗微生物污染功能的电极材料至关重要,然而由于双电层电吸附机制的影响,多数碳基材料的吸附容量受到限制.同时,近年来部分研究学者通过对电极材料进行抗菌化合物的修饰并用于电容法水除菌已得到证明.因此为了实现高效、低成本的同时实现电容脱盐和除菌,本研究提出了一种简便的方法制备氧化石墨烯/聚苯胺/普鲁士蓝纳米复合材料作为类法拉第电极用于电容去离子和水消毒应用.所合成的电极材料具有较高的BET表面积(148.08m^(2)g^(-1))、介孔体积(34.02cm^(3)g^(-1))和孔体积(0.66cm^(3)g^(-1)),在1ag^(-1)下的脱盐容量为91.6mgg^(-1),脱盐率为3.05mgg^(-1)min^(-1).此外,在未添加额外消毒剂的情况下,该复合材料所制备的电极能有效去除和灭活94.0%±3.1%的大肠杆菌,其杀菌效率是活性炭电极的7倍.本研究对未来将普鲁士蓝基复合材料的法拉第电极用于高效环保海水淡化和消毒材料的应用奠定了研究基础.

关键词：氧化石墨烯电容去离子普鲁士蓝水消毒法拉第碳基材料微生物污染海水淡化