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Journal of Geographical Sciences 2020年第7期30卷 1140-1154页

作者： YIN Le DAI Erfu ZHENG Du wang yahui MA Liang TONG Miao Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Mapping the human footprint(HF)makes it possible to quantify human influence,which has had an unprecedented impact on the global *** five categories of human pressure data,this study mapped the HF of the Hengduan Mountain region and assessed the effectiveness of nature reserves in reducing human *** results showed that the HF of the Hengduan Mountain region was generally higher in the south and lower in the *** HF increased by 11.24%over the past 25 years,with faster growth in the *** HF growth rate in nature reserves was much lower than that across the region,which indicated that nature reserves played an important role in reducing the impact of human pressure.A study of Baimaxueshan nature reserve found that establishing nature reserves could effectively reduce the impact of human activities,and no"leakage"*** growth was an important reason for the increased HF in nature *** development of ecotourism in nature reserves must be based on ecological *** the long-term monitoring,evaluation,and management of nature reserves is a basic requirement for their long-term development.

关键词： human influence human footprint nature reserves effectiveness

Vertical migration through faults and hydrocarbon accumulation patterns in deepwater areas of the Qiongdongnan Basin

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Acta Oceanologica Sinica 2014年第12期33卷 96-106页

作者： wang Zhenfeng LIU Zhen CAO Shang SUN Zhipeng ZUO Qianmei wang yahui HE Weijun Zhanjiang Branch of China National Offshore Oil Corporation (CNOOC) Limited Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum

In the Qiongdongnan Basin, faults are well *** on the drilling results, the traps controlled two or more faults are oil-rich. However, when only one fault cut through the sand body, there is no sign for hy-drocarbon accumulation in the sandstone. In terms of this phenomenon, the principle of reservoir-forming controlled by fault terrace is proposed, i.e., when the single fault activates, because of the incompressibility of pore water, the resistance of pore and the direction of buoyancy, it is impossible for hydrocarbon to ac-cumulate in sandstone. But when there are two or more faults, one of the faults acts as the spillway so the hydrocarbon could fill in the pore of sandstone through other faults. In total five gas bearing structures and four failure traps are considered, as examples to demonstrate our findings. According to this theory, it is well-advised that south steep slope zone of Baodao-Changchang Depression, south gentle slope zone of Lingshui Depression, north steep slope zone of Lingshui Depression, and north steep slope zone of Baodao Depression are the most favorable step-fault zones, which are the main exploration direction in next stage.

关键词： principle of reservoir-forming controlled by fault terrace gas bearing structures step-fault zone Qiongdongnan Basin

A New Quantum Algorithm for Computing RSA Ciphertext Period

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Wuhan University Journal of Natural Sciences 2017年第1期22卷 68-72页

作者： wang yahui YAN Songyuan ZHANG Huanguo School of Computer Wuhan University Wuhan 430072Hubei China

Shor proposed a quantum polynomial-time integer factorization algorithm to break the RSA public-key *** this paper,we propose a new quantum algorithm for breaking RSA by computing the order of the RSA ciphertext *** new algorithm has the following properties：1）recovering the RSA plaintext M from the ciphertext C without factoring n; 2）avoiding the even order of the element; 3）having higher success probability than Shor＇s; 4）having the same complexity as Shor＇s.

关键词： information security cryptology RSA cryptography quantum computing

Corrosion Behaviors of Nitride Coatings on Titanium Alloy in NaCl-Induced Hot Corrosion

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Acta Metallurgica Sinica(English Letters) 2021年第10期34卷 1434-1446页

作者： Mingming Zhang Yipeng Feng yahui wang Yunsong Niu Li Xin Yongfeng Li Jianxiu Su Shenglong Zhu Fuhui wang School of Mechanical and Electrical Engineering Henan Institute of Science and TechnologyXinxiang 453003China Corrosion and Protection Division Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchShenyang 110016China Corrosion and Protection Division Shenyang National Laboratory for Materials ScienceNortheastern UniversityShenyang 110819China

TiN and TiAlN coatings were deposited by arc ion plating on titanium alloys to study their hot corrosion resistance when they were exposed to NaCl at 600℃.The microstructure and corrosion behaviors of nitride coatings were studied using scanning electron microscope,X-ray diffraction,electro-probe microanalyzer and X-ray photoelectron *** results showed that nitride coatings with the different compositions and the ones with the same composition but different thicknesses presented different hot corrosion *** and thin TiAlN coatings showed poor corrosion *** internal oxidation attacked the alloy *** corrosion products were mainly consisted of non-protective TiO2 and sodium *** contrast,the thick TiAlN coating presented outstanding corrosion *** sodium salt,the corrosion products were composed of protective Al_(2)O_(3).The increasing thickness of TiAlN significantly enhanced the hot corrosion *** corrosion mechanisms of alloy,TiN and TiAlN coatings were discussed in detail.

关键词： Titanium alloy Nitride Coating Hot corrosion resistance

Polymer-bubbling for one-step synthesis of three-dimensional cobalt/carbon foams against electromagnetic pollution

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Journal of Materials Science & Technology 2021年第34期93卷 7-16页

作者： Fengyuan wang Ping Xu Ning Shi Liru Cui yahui wang Dawei Liu Honghong Zhao Xijiang Han Yunchen Du MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

Constructing three-dimensional(3D)foam-like structure in magnetic metal/carbon composites is regarded as a promising pathway to reinforce their electromagnetic(EM)***,a nitrateassisted polymer-bubbling strategy is reported for the synthesis of Co/carbon foams,which is simply accomplished by direct pyrolyzing the mixture of polyvinylpyrrolidone(PVP)and cobalt nitrate hexahydrate(Co(NO_(3))_(2)·6 H_(2) O).Co(NO_(3))_(2)·6H_(2)O not only plays as the source of Co nanoparticles,but also accounts for the formation of 3D microstructure through releasing *** manipulating the weight ratio of Co(NO_(3))_(2)·6H_(2)O to PVP,the chemical composition,microstructure,and EM properties of these composites can be easily *** the weight ratio reaches 1.5,the resultant composite displays good microwave absorption performance,whose reflection loss intensity and effective absorption bandwidth are superior to those of many common Co/C *** analysis reveals that such architecture is greatly helpful to establish cross-linked conductive networks in the wax matrix,resulting in powerful dielectric loss under low absorber ***,3D microstructure is also beneficial for multiple reflections that equal to extend the transmission path of incident EM *** synthesis strategy and desirable properties of these magnetic carbon foams may render them as the low-cost substitute of 3D graphene for the application against EM pollution.

关键词： Polymer-bubbling Three-dimensional foams Co/C composites Electromagnetic pollution Microwave absorption

Ultrasmall Pt_(2)Sr alloy nanoparticles as efficient bifunctional electrocatalysts for oxygen reduction and hydrogen evolution in acidic media

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Journal of Energy Chemistry 2022年第1期31卷 315-322,I0009页

作者： Xiangnan Liu Shaoyun Hao Guokui Zheng Zhiwei Su yahui wang Qiqi wang Lecheng Lei Yi He Xingwang Zhang Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027ZhejiangChina Institute of Zhejiang University-Quzhou Quzhou 324000ZhejiangChina

Electrocatalytic oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER)in acidic media are vital for the applications of renewable energy ***,the low mass activity of noble Pt urgently needs to be improved due to the strong binding energetics of oxygen species(*O)with Pt *** we report fine PtxSr alloy(-2 nm)supported on N-doped carb on(NC)pyrolyzing from ZIF-8 as bifunctional electrocatalysts toward ORR and HER in acidic *** representative Pt_(2)Sr/NC exhibits an onset potential of 0.94 V *** and half-wave potential of 0.84 V toward ORR,and a low over-potential of 27 mV(10 mA cm^(-2))toward HER,***,the mass activities of Pt_(2)Sr/NC are 6.2 and 2.6 times higher than that of Pt/C toward ORR(at 0.9 V)and HER(at-30 mV),***,Pt_(2)Sr/NC possesses a retention rate of 90.97%toward acidic ORR after 35000 s of continuous *** density functional theory(DFT)calculations and X-ray photoelectron spectroscopy analysis,the incorporation of Sr into Pt forming Pt_(2)Sr alloy redistributes the electronic structures of Pt-Pt bonds,changing the rate-determining step for the ORR on Pt sites from the formation of*OH from*O to the generation of*OOH along with decreasing the energy barrier,which is also confirmed by the downshift of d band ***,the downshift of d band center also leads to the optimization of the adsorption energy(H*)with Pt,significantly improving Pt_(2)Sr/NC toward HER.

关键词： Acidic media Alloy Oxygen reduction reaction Hydrogen evolution reaction Density functional theory

Regulating Uniform Zn Deposition via Hybrid Artificial Layer for Stable Aqueous Zn-Ion Batteries

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Energy Material Advances 2022年第1期2022卷 85-100页

作者： Jingjing Yang Ran Zhao yahui wang Ying Bai Chuan Wu Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019China

Aqueous Zn-ion batteries(ZIBs)have great potential as promising candidates for next-generation energy conversion and storage devices,benefiting from competitive theoretical capacity,low cost,and high ***,further applications of ZIBs are impeded by dendrite generation and side ***,considering that Zn dendrites are caused by nonuniform metal deposition,involving uneven electric field and Zn^(2+)ion flux,a dual-functional carbon-coated NaTi_(2)(PO_(4))_(3)(NTP-C)artificial protective layer with large surface area is constructed onto the surface of metallic Zn to stabilize Zn anode and regulate uniform Zn *** from a synergistic strategy,NTP-C coating not only takes advantages of carbon to provide abundant Zn deposition sites to homogenize nucleation,adjust electric field distribution,and reduce local current density but also utilizes the ionic channel in NTP structure to modulate the distribution of Zn^(2+)flux at the same ***,the NTP-C@Zn symmetrical cell exhibits a stable cycling for more than 600 h with a low polarization(18.6 mV)at 1mAcm^(−2)/1 mAh cm^(−2).Especially,the NTP-C@Zn symmetrical cell even enables a steady plating/stripping process at a harsh condition(100mAcm^(−2))without short circuit,indicating a potential application of high-load electrodes or ***,the NTP-C@Zn//α-MnO_(2)full cell also displays enhanced electrochemical performance for 1200 cycles with a capacity retention of 76.6%under 5C(~1.5A g^(−1)).This work provides a synergistic strategy combining two protective mechanisms and delivers new inspirations for the improvement of stable Zn anode in aqueous ZIBs.

关键词： cycling coating protective

Multi-gait snake robot for inspecting inner wall of a pipeline

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Biomimetic Intelligence & Robotics 2024年第2期4卷 32-41页

作者： Jingwei Liu Man Li yahui wang Da Zhao Rui Deng School of Electrical and Information Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Bejing Key Laboratory of Robot Bionics and Function Research Bejing 100044China

In the field of pipeline inner wall inspection,the snake robot demonstrates significant advantages over other inspection *** a simple traveling wave or meandering motion will suffice for inspecting the inner wall of small-diameter pipes,comprehensively and meticulously inspecting the inner wall of large-diameter pipes requires the snake robot to adopt a helical gait that closely adheres to the inner *** review of existing literature indicates that most research and development on the helical gait of snake robots has focused on the outer surface of cylinders,with very few studies dedicated to developing a helical gait specifically for the inspection of the inner wall of ***,in this study,we propose a helical gait that is suitable for the inner wall of pipes and meets the requirements of gas pipeline *** helical gait is designed using the backbone curve ***,we create a mathematical model for a circular helix curve with constant curvature and torsion,ensuring it is applicable to a snake robot prototype in a laboratory *** calculate the joint angles required for two conical spiral curves with variable curvature and torsion,establish a new model,and define the physical significance of the specific *** ensure the feasibility of the proposed gait,we conduct experiments involving meandering and traveling wave motions to verify the communication and control between the host computer and the snake *** upon this foundation,we further validate the mathematical model of the complex helical motion gait through simulation *** findings provide a theoretical basis for realizing helical movement with a real snake robot.

关键词： Pipeline inner wall detection Snake robot Spiral motion Backbone curve Modeling and simulation

Interaction of Rare Earth Ions in Sr2MgSi2O7：Eu^2＋,Dy^3＋ Material

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Journal of Wuhan University of Technology(Materials Science) 2016年第2期31卷 269-273页

作者：海鸥姜洪义 xu dong wang yahui zheng wei luo ting School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

To discuss the function of Eu and Dy and their interaction in Sr2 Mg Si2O7：Eu^2＋,Dy^3＋ long afterglow material,the Eu and Dy single doped and their co-doped Sr2 Mg Si2O7：Eu^2＋,Dy^3＋ were *** samples were characterized by X-ray diffraction（XRD）,decay curves,photoluminescence（PL）,and thermoluminescence（TL）.The results indicate that Sr2 Mg Si2O7：Eu has afterglow properties,and the doping of Eu ion in Sr2 Mg Si2O7：Eu^2＋,Dy^3＋ can lower the depth of *** ion can not only serve as luminescence center,but also produce traps in the matrix,meanwhile,it also exerts certain influences on the traps produced by Dy in Sr2 Mg Si2O7：Eu^2＋,Dy^3＋.The Dy ion can not act as luminescence center but relates to the change of the traps in the Sr2 Mg Si2O7 matrix.

关键词： phosphors afterglow properties luminescence traps Sr2MgSi2O7:Eu^2+ Dy^3+

Identification methods of coal-bearing source rocks for Yacheng Formation in the western deepwater area of South China Sea

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Acta Oceanologica Sinica 2015年第4期34卷 19-31页

作者： REN Jinfeng ZHANG Yingzhao wang Hua wang yahui GAN Huajun HE Weijun SUN Ming SONG Guangzeng Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences) Ministry of Education Faculty of Earth Resources China University of Geosciences Zhanjiang Branch of China National Offshore Oil Corporation (CNOOC) Limited Guangzhou Marine Geological Survey

Owing to the fact that the coal-beds are with the characteristics of multi-beds, thin single-bed, rapid lateral changes and deep burial, coal-bearing source rocks are difficult to be identified and predicted, especially in the lower exploration deepwater area. In this paper, a new integrative process utilizing geology and geophysics is proposed for better predicting the distribution of coal-bearing source rocks. Coal-beds were identified by the logging responses of“three higher, three lower, and one expand”and carbargilite were recognized by the characteristics of“four higher and one lower”. Based on the above logical decision, coal-beds and carbargilite can be distinguished automatically by cluster analysis of logging curves in verticality. Within the constraints of well-seismic calibration, the coal-beds group also can be detected in horizontality by the integrated representation of“negative phase, higher Q, lower impedance and lower frequency”within the seismic data. However, the distribution of coal-bearing source rocks utilizing geophysical methodology may do not conform to the geological rules of coal accumulation. And then the main geological controlling factors of coal accumulation are comprehensively analyzed as follows：（1） Paleotopography and tectonic subsidence determine the planar range of terrestrial-marine transitional facies markedly;（2） The relative sea level changes affect the accommodation space and shoreline migration, and limit the vertical range of coal-beds. More specifically, the relationship between the accommodation creation rate and the peat accumulation rate is a fundamental control on coal accumulation. The thickest and most widespread coals form where those two factors reached a state of balance;（3） The supply of autochthonous clasts and the distance between deposition places and paleovegetation accumulated area are the critical factor to form abundant coal, which means that if deposition area is close to paleouplift, there would be suff

关键词： Qiongdongnan Basin deepwater area coal-bearing source rocks geological and geophysical methods