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Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China

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Acta Geochimica 2024年第3期43卷 441-458页

作者： qing-qing zhang You-Wei Chen Jian-Feng Gao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South *** Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained *** deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and *** study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and *** element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge *** Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic *** low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization *** contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten *** contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°*** in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH ***,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit.

关键词： Quartz Xingluokeng Tungsten deposit Trace elements South China

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Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

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Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-Lin Li qing-qing zhang Lin Dong Wen-Jun zhang Li-Li Lin Zu-Peng Chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild ***,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional ***,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel *** employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally *** depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination Heterogeneous catalyst

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Potential for soil carbon sequestration under conservation agriculture in a warming climate

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Science Bulletin 2024年第13期69卷 2030-2033页

作者： Lijun Yu Wen zhang Jingjing Liu Wenjuan Sun qing zhang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Anyang Meteorological Service Anyang 455000China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Agricultural soil has numerous links with climate *** comprises a substantial part of farming systems that are affected by climate change and can significantly impact food security[1].An increase in the soil carbon(C)stock is associated with an increase in the crop ***,agricultural soil remains a source for all three major greenhouse gases(GHGs),i.e.,carbon dioxide(CO_(2)),methane and nitrous oxide,which contributes directly to climate *** addition,enhancing soil C sequestration in agricultural land could offset GHG emissions,promote more sustainable and climate-resilient agricultural systems.

关键词： soil warming agricultural

A Coupled Thermomechanical Crack Propagation Behavior of Brittle Materials by Peridynamic Differential Operator

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 339-361页

作者： Tianyi Li Xin Gu qing zhang College of Architectural Engineering Jiangsu Open UniversityNanjing210036China Department of Engineering Mechanics Hohai UniversityNanjing211100China

This study proposes a comprehensive,coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator(PDDO),eliminating the need for calibration *** model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics *** simulations conducted on granite and ceramic materials,this model demonstrates its *** successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during *** account for material heterogeneity,the model utilizes the Shuffle algorithm andWeibull distribution,yielding results that align with numerical simulations and experimental *** coupled thermomechanical model shows great promise for analyzing intricate thermomechanical phenomena in brittle materials.

关键词： Peridynamic differential operator thermomechanical coupling heterogeneity numerical simulation

Lightweight Malicious Code Classification Method Based on Improved Squeeze Net

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Computers, Materials & Continua 2024年第1期78卷 551-567页

作者： Li Li Youran Kong qing zhang School of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the growth of the Internet,more and more business is being done online,for example,online offices,online education and so *** this makes people’s lives more convenient,it also increases the risk of the network being attacked by malicious ***,it is important to identify malicious codes on computer systems ***,most of the existing malicious code detection methods have two problems:(1)The ability of the model to extract features is weak,resulting in poor model performance.(2)The large scale of model data leads to difficulties deploying on devices with limited ***,this paper proposes a lightweight malicious code identification model Lightweight Malicious Code Classification Method Based on Improved SqueezeNet(LCMISNet).In this paper,the MFire lightweight feature extraction module is constructed by proposing a feature slicing module and a multi-size depthwise separable convolution *** feature slicing module reduces the number of parameters by grouping *** multi-size depthwise separable convolution module reduces the number of parameters and enhances the feature extraction capability by replacing the standard convolution with depthwise separable convolution with different convolution kernel *** addition,this paper also proposes a feature splicing module to connect the MFire lightweight feature extraction module based on the feature reuse and constructs the lightweight model *** malicious code recognition accuracy of LCMISNet on the BIG 2015 dataset and the Malimg dataset reaches 98.90% and 99.58%,*** proves that LCMISNet has a powerful malicious code recognition *** addition,compared with other network models,LCMISNet has better performance,and a lower number of parameters and computations.

关键词： Lightweight neural network malicious code classification feature slicing feature splicing multi-size depthwise separable convolution

Dual template-induced construction of three-dimensional porous SiO2/NC/Co-CNTs heterostructure with highly dispersed active sites for efficient oxygen evolution reaction

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Tungsten 2024年第3期6卷 585-595页

作者： Hai-Qi zhang Xiao-Jun Zeng qing-qing zhang Zu-Liang zhang Chu-Long Jin Rong-Hai Yu School of Materials Science and Engineering Jingdezhen Ceramic University School of Materials Science and Engineering Beihang University

The development and exploration of efficient and economical electrocatalysts for oxygen evolution reaction（OER） represents the main bottleneck to unlocking a sustainable energy scenario based on elec trocataly tic water *** scale integration of three-dimensional（3D） porous heterostructure with highly dispersed active sites and good structural stability is ***,a dual template route is developed to construct the 3D porous SiO2/nitrogen-doped carbon（NC）/Co-carbon nano tubes（CNTs） hetero ***,the hard template（SiO2nano spheres） contributes to 3D porous structure,increases the specific surface area,and promotes the contact area of the *** the same time,the soft template（basic zinc carbonate） can control the growth of 1D CNTs and facilitate the exposure of the active ***,3D porous SiO2/NC/Co-CNTs hetero structure inherits highly dispersed Co nanoparticles coated by *** conductive channels and abundant N hetero atoms doping are reasonably constructed by a dual template ***,SiO2/NC/Co-CNTs catalyst provides an extraordinary activity for the OER in alkaline media,with a low overpotential of 298 mV at a current density of 10 mA·***,SiO2/NC/Co-CNTs hetero structure enables excellent long-term durability with a 10 mV decay in overpotential after 3000 cyclic voltammetry cycles,and 97% remain in current density over 20 *** is believed that this dual template strategy can provide a new and simple way to construct a highly dispersed active site in electrocatalysts.

关键词： Dual template High dispersion Porous heterostructure Conductive channels Oxygen evolution reaction

Physics of cavitation near particles

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Journal of Hydrodynamics 2024年第1期36卷 102-118页

作者： Jia-xin Yu Xiao-yu Wang Jun-wei Shen Jin-sen Hu Xiang-qing zhang Da-qing He Yu-ning zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The combined effect of cavitation and silt abrasion presents a great challenge and threat to secure the operation and the efficiency of hydraulic machineries working in sediment-laden *** present paper critically reviews the current research progress on the interaction mechanisms of the bubbles and the ***,the analytical models including boundary treatment methods for predicting the jet dynamics of the bubble collapse near particles are ***,the bubble collapsing dynamics,jet dynamics and shock wave characteristics near particles are revealed both experimentally and ***,the bubble-particle-wall system is investigated with a focus on microjets.

关键词： Cavitation bubble particle jet shock wave

Contact engineering for temperature stability improvement of Bi-contacted MoS2 field effect transistors

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Science China(Information Sciences) 2024年第6期67卷 172-179页

作者： Zizheng LIU qing zhang Xiaohe HUANG Chunsen LIU Peng ZHOU State Key Laboratory of Integrated Chip and Systems School of MicroelectronicsZhangjiang Fudan International Innovation CenterFudan University Frontier Institute of Chip and System Shanghai Key Lab for Future Computing Hardware and SystemFudan University Shaoxin Laboratory

Semimetallic bismuth（Bi） is one of the most effective strategies for reducing the contact resistance of two-dimensional transition metal dichalcogenide field effect transistors（FETs）. However, the low melting point of Bi contact（271.5℃） limits its reliable applications. In this study, we demonstrated that the temperature stability of Bi-contacted electrodes could be improved by inserting a high-melting point semimetallic antimony（Sb） between the Bi contacting layer and the gold（Au） capping layer. The proposed Bi/Sb/Au contact electrodes tended to form a metal mixture with a continuous surface during the heating process（Voids appeared on the surface of the Bi/Au contact electrodes after heating at 120℃）. Because of the improved contacting layer formed by the semimetal Bi/Sb alloy, the fabricated Bi/Sb/Au-contacted molybdenum sulfide（MoS2） FETs with different gate lengths demonstrated higher on-state current stability after heating treatment than the Bi/Au contact. Because of the Bi/Sb/Au contact and poly（methyl methacrylate） package, the MoS2FETs demonstrated time stability of at least two months from the almost unchanged transfer characteristics. The electrical stability indicates that the insertion of semimetallic Sb is a promising technology for reliable Bi-based contact.

关键词： temperature stability semimetallic bismuth contact semimetallic antimony contact MoS$_{2}$ FETs time stability

A GAN-EfficientNet-Based Traceability Method for Malicious Code Variant Families

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Computers, Materials & Continua 2024年第7期80卷 801-818页

作者： Li Li qing zhang Youran Kong School of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

Due to the diversity and unpredictability of changes in malicious code,studying the traceability of variant families remains *** this paper,we propose a GAN-EfficientNetV2-based method for tracing families of malicious code *** method leverages the similarity in layouts and textures between images of malicious code variants from the same source and their original family of malicious code *** method includes a lightweight classifier and a *** classifier utilizes the enhanced EfficientNetV2 to categorize malicious code images and can be easily deployed on mobile,embedded,and other *** simulator utilizes an enhanced generative adversarial network to simulate different variants of malicious code and generates datasets to validate the model’s *** process helps identify model vulnerabilities and security risks,facilitating model enhancement and *** classifier achieves 98.61%and 97.59%accuracy on the MMCC dataset and Malevis dataset,*** simulator’s generated image of malicious code variants has an FID value of 155.44 and an IS value of 1.72±*** classifier’s accuracy for tracing the family of malicious code variants is as high as 90.29%,surpassing that of mainstream neural network *** meets the current demand for high generalization and anti-obfuscation abilities in malicious code classification models due to the rapid evolution of malicious code.

关键词： Malicious code variant traceability feature reuse lightweight neural networks code visualization attention mechanism