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Constraints on the Ediacaran-Cambrian boundary in deep-water realm in South China: Evidence from zircon CA-ID-TIMS U-Pb ages from the topmost Liuchapo Formation

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Science China Earth Sciences 2020年第8期63卷 1176-1187页

作者： Wei WANG mingzhong zhou.zhu.in chu Junjie XU Chaofeng LI Taiyi LUO Jinghui GUO State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China School of Geographical and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China:China University of GeosciencesBeijing 100083China:State Key Laboratory of Ore Deposit GeochemistryInstitute of GeochemistryChinese Academy of SciencesGuiyang 550002China

The placement of the Ediacaran-Cambrian boundary in deep-water realm in South China and the high-precision temporal framework for the Ediacaran-Cambrian transition in this region have not yet been completely solved. Recently, we have found two K-bentonite beds in the top of the Liuchapo Formation at the Pingyin section, Guizhou Province. It provides an opportunity for constructing the temporal framework of the transitional strata on the Yangtze Platform in South China and for determining the Ediacaran-Cambrian boundary in this area. In this study, we conducted high-precision CA-ID-TIMS U-Pb dating on zircons from the two K-bentonites. The ages of the two K-bentonites were precisely constrained at 536.40±0.47/1.1/1.2 Ma(2σ, n=7, MSWD=0.92) and 541.48±0.46/1.1/1.2 Ma(2σ, n=8, MSWD=1.3). Combining the geochronological results with organic carbon isotope data of chert in the topmost Liuchapo Formation from the section, we suggest that the EdiacaranCambrian boundary should be consistent with a significant negative organic carbon isotope excursion between the two Kbentonites. The scheme of the Ediacaran-Cambrian boundary in this study is of great significance for global correlation, and further for unravelling the information of the terminal Ediacaran-early Cambrian ocean.

关键词： Liuchapo Formation Yangtze Platform Ediacaran-Cambrian CA-ID-TIMS Organic carbon isotope

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Ultrathin nanosheets of cobalt-nickel hydroxides hetero-structure via electrodeposition and precursor adjustment with excellent performance for supercapacitor

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Journal of Energy Chemistry 2018年第2期27卷 591-599页

作者： Min Wei Qingsong Huang Yanping zhou zhu Peng Wei chu School of Chemical Engineering Sichuan University School of Electronics and Information Engineering Sichuan University

A homogeneous better-dispersed ultrathin nanosheets（ca. 5 nm） of cobalt-nickel layered double hydroxides（LDH） supported on nickel foam scaffold was synthesized using controllable electrodeposition approach for high efficiency electrode materials of new supercapacitor. The morphology and electrochemical performances of the samples can be controlled by adjusting the precursor ratio, i.e., Ni（OAc）2/Co（NO3）2 molar ratio in the electrodeposition approach. With the increase of this molar ratio, the electrochemical performances give a volcano trend. When the optimized molar ratio is 0.64/0.36, the hybrid delivered a high specific capacitance of 1587.5 F g-1 at a current density of 0.5 A g-1, with good rate capability（1155 F g-1 was retained even at 10 A g-1） and a robust recycle stability（remaining 91.5% after 1000 cycles at 5 A g-1）. The good performance could be attributed to the enlarged interlayer spacing, ultrathin nanosheets and synergistic effects between Co（OH）2 and Ni（OH）2. Furthermore, an asymmetric supercapacitor with a high energy density of 34.5 Wh kg-1 at 425 W kg-1 and excellent cycling stability of 85.4% after 5000 charge-discharge cycles at 2 A g-1 was fabricated. We believe that this fantabulous new electrode material would have encouraging applications in electrochemical energy storage and a wide readership.

关键词： Ultrathin nanosheets CoNi layered double hydroxides (LDH) electrode Ni(OAc)2/Co(NO3)2 precursors High performance Electrodeposition Asymmetric supercapacitor

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Design,test,and verification of in-situ condition preserved coring and analysis system in lunar-based simulation environment

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International Journal of Mining Science and Technology 2024年第9期34卷 1259-1272页

作者： Haichun Hao mingzhong Gao Yan Wu Zheng Gao Yongcheng Li Xuemin zhou Peng chu Xuan Wang Jiahua Li Lang zhou Jie Song Tianxiang Ao Yikun Yang State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering Shenzhen UniversityShenzhen 518060China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy Shenzhen UniversityShenzhen 518060China

The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and *** exploration and research in the field of deep space science,especially lunar-based exploration,is a scientific strategy that has been pursued in China and *** and sampling are key to accurate exploration of the desirable characteristics of deep lunar *** this study,an in-situ condition preserved coring(ICP-Coring)and analysis system,which can be used to test drilling tools and develop effective sampling strategies,was *** key features of the system include:(1)capability to replicate the extreme temperature fluctuations of the lunar environment(-185 to 200℃)with intelligent temperature control;(2)ability to maintain a vacuum environment at a scale of 10^(-3) Pa,both under unloaded conditions within Ф580 mm×1000 mm test chamber,and under loaded conditions using Ф400 mm×800 mm lunar rock simulant;(3)application of axial pressures up to 4 MPa and confining pressures up to 3.5 MPa;(4)sample rotation at any angle with a maximum sampling length of 800 mm;and(5)multiple modes of rotary-percussive drilling,controlled by penetration speed and weight on bit(WOB).Experimental studies on the drilling characteristics in the lunar rock simulant-loaded state under different drill bit-percussive-vacuum environment configurations were *** results show that the outgassing rate of the lunar soil simulant is greater than that of the lunar rock simulant and that a low-temperature environment contributes to a reduced vacuum of the lunar-based simulated *** rotary-percussive drilling method effectively shortens the sampling *** increasing sampling depth,the temperature rise of the drilling tools tends to rapidly increase,followed by slow growth or steady *** temperature rise energy accu

关键词： Lunar-based Large temperature difference Vacuum Drilling and coring System design

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Aerial intelligent reflecting surface for secure wireless networks:Secrecy capacity and optimal trajectory strategy

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Intelligent and Converged Networks 2022年第1期3卷 119-133页

作者： Hehao Niu Zheng chu Zhengyu zhu Fuhui zhou Institute of Electronic Countermeasure National University of Defense TechnologyHefei 230037China. Institute for Communication Systems University of SurreyGuildfordGU27XHUK Shaanxi Key Laboratory of Information Communication Network and Security Xi’an University of Posts&TelecommunicationsXi’an 710121China School of Information Engineering Zhengzhou UniversityZhengzhou 450001China College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronauticsand also with the Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum SpaceNanjing University of Aeronautics and AstronauticsNanjing 210000China.

This work investigates the potential of the aerial intelligent reflecting surface(AIRS)in secure communication,where an intelligent reflecting surface(IRS)carried by an unmanned aerial vehicle(UAV)is utilized to help the communication between the ground ***,we formulate the joint design of the AIRS’s deployment and the phase shift to maximize the secrecy *** solve the non-convex objective,we develop an alternating optimization(AO)approach,where the phase shift optimization is solved by the Riemannian manifold optimization(RMO)method,while the deployment optimization is handled by the successive convex approximation(SCA)***,to reduce the computational complexity of the RMO method,an element-wise block coordinate descent(EBCD)based method is *** results verify the effect of AIRS in improving the communication security,as well as the importance of designing the deployment and phase shift properly.

关键词： aerial intelligent reflecting surface(AIRS) unmanned aerial vehicle(UAV) alternating optimization Riemannian manifold optimization(RMO) element-wise block coordinate descent(EBCD)

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Paving the way toward soil safety and health:current status,challenges,and potential solutions

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 63-73页

作者： Chiheng chu Lizhong zhu College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China

Soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon ***,the health of soil faces global threats from human activities,particularly widespread contamination by industrial *** physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional *** solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale ***,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of ***,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring *** the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

关键词： Soil safety and health Source emission reduction Process monitoring and simulation Green remediation technology Soil health management

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Microwave Synthesis of Cuprous Oxide Micro-/Nanocrystals with Different Morphologies and Photocatalytic Activities

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Journal of Materials Science & Technology 2011年第4期27卷 289-295页

作者： Qingwei zhu Yihe Zhang Jiajun Wang Fengshan zhou Paul K. chu State Key Laboratory of Geological Processes & Mineral Resources National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences (Beijing) Beijing 100083 China Department of Powder Metallurgy and Special Materials General Research Institute of Non-Ferrous MetalBeijing 100088 China Department of Physics & Materials Science City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong China

Cuprous oxide micro-/nanocrystals were synthesized by using a simple liquid phase reduction process under microwave irradiation. Copper sulfate was used as the starting materials and macromolecule surfactants served as the templates. The morphologies phase and optical properties of them are characterized by X-ray diffraction （XRD）, scanning elec- tron microscopy （SEM） and ultraviolet-visible diffuse reflection absorptive spectra （UV-vis/DRS）, respectively. The crystals had four different shapes, namely spheres, strips, octahedrons, and dandelions. The photocatalytic behavior of the cuprous oxide particles were investigated by monitoring the degradation of rhodamine B. In spite of the differ- ent morphologies, all of the cuprous oxide micro-/nanocrystals exhibited photocatalytic activities under visible light irradiation in the following order： dandelions, strips, spheres, and octahedral crystals. The photocatalytic degradation rates of rhodamine B are 56.37%, 55.68%, 51.83% and 46.16%, respectively. The morphology affects significantly the photocatalytic performance.

关键词： Cuprous oxide Synthesis Morphology Photocatalytsis

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Fault-Tolerant Operation of Five-Phase Permanent Magnet Synchronous Motor with Independent Phase Driving Control

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CES Transactions on Electrical Machines and Systems 2022年第1期6卷 105-110页

作者： Yongqing Wei mingzhong Qiao Peng zhu College of Electrical Engineering Naval University of EngineeringWuhan430033China

The multi-phase motor drive system with multiple H-bridge power supply has high fault tolerance,which is widely used in aerospace,electric vehicle,ship integrated power system and other *** this paper,a fault-tolerant control strategy based on decoupling control and stator current compensation is proposed for the propulsion system of five-phase PMSM with independent ***,the mathematical model of PMSM is established by using vector space decoupling method;Secondly,a stator current compensation method is adopted to carry out fault-tolerant control after the motor has single-phase and two-phase open-circuit faults and the fault-tolerant control system based on decoupling control is established;Finally,the decoupling control model and the fault-tolerant control of stator current compensation are verified by the simulation and *** simulation and experiment results show that the method can reduce the torque ripple caused by the stator winding open-circuit fault,and the operation performance of the motor under fault condition is significantly improved.

关键词： Five-Phase permanent magnet synchronous motor H-bridge inverter Fault-tolerant control Vector space decoupling

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Microwave-Assisted Synthesis of NiCo_2O_4 Double-Shelled Hollow Spheres for High-Performance Sodium Ion Batteries

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Nano-Micro Letters 2018年第1期10卷 117-123页

作者： Xiong Zhang Yanping zhou Bin Luo Huacheng zhu Wei chu Kama Huang School of Chemical Engineering Sichuan University School of Electronics and Information Engineering Sichuan University

The ternary transitional metal oxide NiCo_2O_4 is a promising anode material for sodium ion batteries due to its high theoretical capacity and superior electrical conductivity. However, its sodium storage capability is severely limited by the sluggish sodiation/desodiation reaction kinetics. Herein, NiCo_2O_4 double-shelled hollow spheres were synthesized via a microwave-assisted, fast solvothermal synthetic procedure in a mixture of isopropanol and glycerol, followed by annealing. Isopropanol played a vital role in the precipitation of nickel and cobalt,and the shrinkage of the glycerol quasi-emulsion under heat treatment was responsible for the formation of the double-shelled nanostructure. The as-synthesized productwas tested as an anode material in a sodium ion battery,was found to exhibit a high reversible specific capacity of 511 m Ahg^(-1) at 100 m Ag^(-1), and deliver high capacity retention after 100 cycles.

关键词： NiCo2O4 Double-shelled hollow sphere Microwave Sodium ion battery

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Visualization Feature and CNN Based Homology Classification of Malicious Code

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Chinese Journal of Electronics 2020年第1期29卷 154-160页

作者： chu Qianfeng LIU Gongshen zhu Xinyu School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

The malicious code brings a serious security threat. Researchers have found that many new types of malicious code are variants of the existing *** homology classification of the unknown malicious code can find its corresponding family in which all the code share inherent similarities from the database, so that the defenders can make rapid response and *** use the algorithm of malicious code visualization to translate the homology classification problem into the image classification problem. A convolution neural network for malicious code image is constructed. We train it to complete the malicious code homology classification on two different datasets. The results show that our work outperforms most of existing work with the accuracy of 98.60%.

关键词： Malicious code Homology classification Malicious code image Convolutional neural network

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Inversion Optimization Strategy Based on Primitives with Complement Attributes

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Journal of Computer Science & Technology 2021年第5期36卷 1145-1154页

作者： Hui-Ming Tian zhu-Fei chu Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211China

Inverters or logic primitives that have complement attributes are essential to building a logical complement *** and NOR operations which have complement attributes are of high interest for complementary metal-oxidesemiconductor(CMOS)technology,as they can be easily implemented in *** from the logic models used in standard CMOS,several nano-emerging technologies,such as quantum-dot cellular automata(QCA)and spin torque majority gates,are in favor of realizing a majority voter function but imposing difficulties in implementing *** studies pay lots of effort in optimizing the number of inverters in logic representations,whereas the mapping using primitives with complement attributes is not a major *** this paper,we establish a technology mapping method from logic representations to nanotechnology primitives by considering NAND-NOR-Inverter(NNI)and exclusive-NOR(XNOR)*** adopt XOR-Majority Graph(XMG)as a logic *** proposed mapping method is evaluated using the QCA *** results over EPFL benchmark suites show we achieve 11.77%and 30.13%reductions in the area and the number of inverters,respectively.

关键词： inversion optimization quantum-dot cellular automata majority-of-three NAND-NOR-Inverter(NNI)

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