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Effects of electrolytic concentration on properties of micro-arc film on Ti6Al4V alloy

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Mining Science and Technology 2009年第2期19卷 220-224页

作者： shi Xing-ling WANG Qing-liang WANG Fu-shun GE shi-rong School of Material Science and Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

To study the effect of electrolytic concentration,bioactive ceramic films containing Ca and P on the surface of the Ti6Al4V alloy were prepared by micro-arc oxidation(MAO) in aqueous solutions of different ***,micro-morphology,wettability of the films and their corrosion behavior in a Hank's SBF were *** experimental results show that the film is mainly composed of anatase,rutile and amorphous *** an increase in electrolytic concentration,the ratio of rutile in films enlarge and small amounts of calcium phosphate(Ca3(PO4)2) and hydroxyapatite(HA) *** number of micropores in films increases but their dimensions decrease and their porosities increase *** the surface roughness of MAO film increases with concentration,the wettablility of the oxide film improves continually,while micro-hardness increases at first and then *** treatment clearly improves the corrosion resistance of substrates in a Hank's SBF.

关键词： titanium alloy micro-arc oxidation roughness contact angle micro-hardness anodic polarization

Co-infection of Wolbachia and Spiroplasma in spider mite Tetranychus truncatus increases male fitness

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Insect Science 2020年第5期27卷 921-937页

作者： Kang Xie Yi-Jia Lu Kun Yang shi-Mei huo Xiao-Yue Hong Department of Entomology Nanjing Agricultural UniversityNanjingChina

Wolbachia and Spiroplasma are intracellular bacteria that are of great interest to entomologists,because of their ability to alter insect host biology in multiple *** the spider mite Tetranychus truncatus,co-infection of Wolbachia and Spiroplasma can induce cytoplasmic incompatibility(CI)and fitness costs;however,lttle is known about the effect of co-infection at the genetic level and the molecular mechanisms underlying *** this study,we explored the influence of the two symbionts on male mite host fitness and used RNA sequencing to generate the transcriptomes of T truncatus with four different types of *** total,we found symbiont-infected lines had a higher hatch proportion than the uninfected line,and the development time of the uninfected line was longer than that of the other ***-infection changed the expression of many genes related to digestion detoxification,reproduction,immunity and oxidation *** results indicate that co-infection of Wolbachia and Spiroplasma confers multiple effects on their hosts,and helps iluminate the complex interactions between endosymbionts and arthropods.

关键词： co-infection development time Spiroplasma Tetranychus truncatus tran-scriptome Wolbachia

Adaptive PID controller based on Q-learning algorithm

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CAAI Transactions on Intelligence Technology 2018年第4期3卷 235-244页

作者： Qian shi Hak-Keung Lam Bo Xiao shun-Hung Tsai Department of Informatics King’s College LondonBush HouseStrand Campus30 AldwychLondon WC2B 4BGUK Hamlyn Centre for Robotic Surgery Imperial College LondonLondon SW7 2AZUK Graduate Institute of Automation Technology National Taipei University of TechnologyTaipei 10608Taiwan

An adaptive proportional–integral–derivative(PID)controller based on Q-learning algorithm is proposed to balance the cart–pole system in simulation *** controller was trained using Q-learning algorithm and implemented the learned Q-tables to change the gains of linear PID controllers according to the state of the system during the control *** adaptive PID controller based on Q-learning algorithm was trained from a set of fixed initial positions and was able to balance the system starting from a series of initial positions that are different from the ones used in the training session,which achieved equivalent or even better performances in comparison with the conventional PID controller and the controller only uses Q-learning *** indicates the advantage of the adaptive PID controller based on Q-learning algorithm both in the generality of balancing the cart–pole system from a relatively wide range of initial positions and in the stabilisability of achieving smaller steady-state error.

关键词： Adaptive PID the controller

Experimental study on hypersonic crossflow instability over a swept flat plate by flow visualization

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Acta Mechanica Sinica 2021年第9期37卷 1395-1403,I0002页

作者： Hai-Bo Niu shi-He Yi Jun-Jie huo Wen-Peng Zheng Xiao-Lin Liu College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China

An experimental study on the traveling crossflow instability over a 60∘swept flat plate was *** Mach number is 6,the angle of attack of the model is 5∘.The traveling crossflow waves and the secondary instability of the traveling crossflow waves were visualized by nano-tracer-based planar laser scattering(NPLS)*** the spanwise NPLS images,the traveling crossflow waves appeared as regular strikes,and the secondary instability appeared as small eddies attached to *** wavelet transform was used to study the wavelength contents of the traveling crossflow *** most amplified wavelength is stable before the secondary instability happening,which is around 12 mm at Re_(∞)=3.45×10^(6)m^(−1).Besides,the Reynolds number effects on the boundary layer transition and traveling crossflow instability were discussed.

关键词： Crossflow instability Swept flat plate Flow visualization Wavelet analysis Boundary layer transition

Geochemical Characteristics and Sources of Ore-forming Fluids of the Mayuan Pb-Zn Deposit,Nanzheng,Shaanxi,China

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Acta Geologica Sinica(English Edition) 2015年第3期89卷 783-793页

作者： LIU Shuwen LI Ronxi CHI Guoxiang ZENG Rong LIU Lingfang shi shun Chang'an University Key Laboratory for the study of Focused Magmatism and Giant Ore Deposits MLR University of Regina Geophysical and Geochemical Exploration Corporation of Northwest Geological Exploration and Mining Bureau for Nonferrous Metals

The Mayuan stratabound Pb-Zn deposit in Nanzheng,Shaanxi Province,is located in the northern margin of the Yangtze Plate,in the southern margin of the Beiba *** orebodies are stratiform and hosted in breciated dolostone of the Sinian Dengying *** ore minerals are primarily sphalerite and galena,and the gangue minerals comprise of dolomite,quartz,barite,calcite and solid *** inclusions from ore-stage quartz and calcite have homogenization tempreatures from 98 to 337℃ and salinities from 7.7 wt%to 22.2 wt%（NaCl equiv.）.The vapor phase of the inclusions is mainly composed of CH_4 with minor CO_2 and H_*** δD_（fluid） values of fluid inclusions in quartz and calcite display a range from-68‰ to-113‰（SMOW）,and the δ^（18）O_（fluid）values calculated from δ^（18）O_（quartz） and δ^（18）O_（calcite） values range from 4.5‰ to 16.7‰（SMOW）.These data suggest that the ore-forming fluids may have been derived from evaporitic sea water that had reacted with organic *** δ^（13）C_（CH4） values of CH_4 in fluid inclusions range from-37.2‰ to-21.0‰（PDB）,suggesting that the CH_4 in the ore-forming fluids was mainly derived from organic ***,together with the abundance of solid bitumen in the ores,suggest that organic matter played an important role in mineralization,and that the thermochemical sulfate reduction（TSR） was the main mechanism of sulfide *** Mayuan Pb-Zn deposit is a carbonate-hosted epigenetic deposit that may be classified as a Mississippi Valley type（MVT） deposit.

关键词： fluid inclusion ore-forming fluids organic matter Mayuan Pb-Zn deposit Shaanxi

Synthesis and characterization of fluorescence active G_(4)-quartet and direct evaluation of self-assembly impact on emission

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Chinese Chemical Letters 2022年第9期33卷 4203-4207页

作者： Ying He Mengjia Liu shun Teng Lukasz Wojtas Guangxin Gu Xiaodong shi Department of Chemistry University of South FloridaTampaFL 33620United States Department of Materials Science Fudan UniversityShanghai 200438China

Fluorescence(FL)active 8-aryl guanosine derivatives were prepared and applied for cation mediated self-assembly to form the H-bonded G_(8)-*** p-cyano(p-CN)and 8-anthracene(8-An)substituted guanosines were identified to give the strongest fluorescence with the formation of G_(8)-octamers(G_(8))both in solution(NMR)and solid state(X-ray).This well-defined G_(8)-octamer system has provided the first direct evidence on the self-assembled G-quadruplex fluorescence emission with aggregation-induced emission(AIE),which could be applied as the foundation for FL molecular probe design toward G-quadruplex recognition.

关键词： Self-assembly H-bonding G_(4)-quartet Fluorescence Aggregation induced emission

PosFuzz:augmenting greybox fuzzing with effective position distribution

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Cybersecurity 2023年第4期6卷 123-143页

作者： Yanyan Zou Wei Zou JiaCheng Zhao Nanyu Zhong Yu Zhang Ji shi Wei huo Institute of Information Engineering Chinese Academy of SciencesBeijingChina School of Cyber Security University of Chinese Academy of SciencesBeijingChina State Key Lab of Processors Institute of Computing TechnologyChinese Academy of SciencesBeijingChina Key Laboratory of Network Assessment Technology Chinese Academy of SciencesBeijingChina Beijing Key Laboratory of Network Security and Protection Technology BeijingChina Zhongguancun Laboratory BeijingChina

Mutation-based greybox fuzzing has been one of the most prevalent techniques for security vulnerability discovery and a great deal of research work has been proposed to improve both its efficiency and ***-based greybox fuzzing generates input cases by mutating the input seed,i.e.,applying a sequence of mutation operators to randomly selected mutation positions of the ***,existing fruitful research work focuses on scheduling mutation operators,leaving the schedule of mutation positions as an overlooked aspect of fuzzing *** paper proposes a novel greybox fuzzing method,PosFuzz,that statistically schedules mutation positions based on their historical *** makes use of a concept of effective position distribution to represent the semantics of the input and to guide the *** first utilizes Good-Turing frequency estimation to calculate an effective position distribution for each mutation *** then leverages two sampling methods in different mutating stages to select the positions from the *** have implemented PosFuzz on top of AFL,AFLFast and MOPT,called Pos-AFL,-AFLFast and-MOPT respectively,and evaluated them on the UNIFUZZ benchmark(20 widely used open source programs)and LAVA-M *** result shows that,under the same testing time budget,the Pos-AFL,-AFLFast and-MOPT outperform their counterparts in code coverage and vulnerability discovery *** with AFL,AFLFast,and MOPT,PosFuzz gets 21%more edge coverage and finds 133%more paths on *** also triggers 275%more unique bugs on average.

关键词： Greybox fuzzing Mutation position Mutation operator Code coverage Vulnerability discovery

Real-time process control of powder bed fusion by monitoring dynamic temperature field

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Advances in Manufacturing 2020年第3期8卷 380-391页

作者： Xiao-Kang Huang Xiao-Yong Tian Qi Zhong shun-Wen He Chun-Bao huo Yi Cao Zhi-Qiang Tong Di-Chen Li State Key Laboratory of Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an710049People’s Republic of China

This study aims to optimize the uniformity of the temperature field during sintering to improve part performance.A temperature-field monitoring system is established based on an infrared thermal imager and the temperature field data obtained during the sintering of a part can be measured in real *** relationship among the sintering temperature field,sintering process parameters,and part performance is established ***,a temperature field monitoring and analysis system is constructed,and various sintering temperature-field control strategies are established for various part ***,a dynamic control strategy for controlling the temperature field during sintering is proposed,experimentally validated,and fully integrated into a developed powder bed fusion(PBF)*** eight-shaped standard parts,the range of sintering temperature field is optimized from 44.1℃to 19.7℃,whereas the tensile strength of the parts increased by 15.4%.For large-size H parts,localized over burning is eliminated and the final quality of the part is *** strategy is critical for the optimization of the PBF process for large-sized parts,in particular in the large-sized die manufacturing industry,which offers promise in the optimization of part performance.

关键词： Powder bed fusion(PBF) Sintering temperature field Monitoring system Infrared thermal imager

A self-powered and concealed sensor based on triboelectric nanogenerators for cultural-relic anti-theft systems

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Nano Research 2022年第9期15卷 8435-8441页

作者： Baocheng wang Xiaoying Zhai Xuelian Wei Yapeng shi Xiaoqing huo Ruonan Li Zhiyi Wu Zhong Lin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Nanoscience and Technology University of Chinese Academy of ScienceBeijing 100049China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’an 710072China CUSTech Institute of Technology Wenzhou 325024China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

The theft prevention for cultural relics in museums,field excavation sites,and temporary exhibition events is of extreme ***,traditional anti-theft technologies such as infrared monitoring and radio frequency identification are highly costly,power-consuming,and easy to ***,a transparent,ultrathin,and flexible triboelectric sensor(TUFS)with a simple and low-cost method is *** a thickness,weight,and transmittance of 92μm,0.12 g,and 89.4%,the TUFS manifests superb *** from the characteristic of triboelectric nanogenerators,the TUFS responds effectively to common cultural-relic ***,distinguished electrical responses can be obtained even for very small weights(10 g)and areas(1 cm^(2)),proving the sensitivity and wide range of use of the ***,we construct a concealed cultural-relic anti-theft system that enables real-time alarming and accurate positioning of cultural relics,which is expected to strengthen the security level of the existing museum anti-theft systems.

关键词： concealed sensor self-powered triboelectric nanogenerator cultural relic anti-theft