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Microstructure and Mechanical Properties of martensitic Stainless Steel 6Cr1.MoV

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Journal of Iron and Steel Research International 2012年第3期19卷 56-61页

作者： ma Dang-shen1. CHI Hong-xiao1.2. ZHOU {1., YONG Qi-long1.2.(1. institute for Structural materials, Central Iron and Steel Research institute, beijing 1.0081. {12. 2. Faculty of materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, Yunnan, {12.) [a] institute for Structural {1.terials Central Iron and Steel Research Institute Beijing 100081 China [b] Faculty of materials Science and Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China

martensitic stainless steel containing Cr of 1.% to 1.%（mass percent） are common utilized in quenching and tempering processes for knife and cutlery steel. The properties obtained in these materials are significantly influ- enced by matrix composition after heat treatment, especially as Cr and C content. Comprehensive considered the hardness and corrosion resistance, a new type martensitic stainless steel 6Crl5MoV has been developed. The effect of heat treatment processes on microstructure and mechanical properties of 6Crl5MoV martensitic stainless steel is emphatically researched. Thermo-Calc software has been carried out to thermodynamic calculation; OM, SEM and TEM have been carried out to microstructure observation; hardness and impact toughness test have been carried out to evaluate the mechanical properties. Results show that the equilibrium carbide in 6Cr1.MoV steel is M2. C6 car- bide, and the M2. C6 carbides finely distributed in annealed microstructure. 6Crl5MoV martensitic stainless steel has a wider quenching temperature range, the hardness value of steel 6Cr1.MoV can reach to HRC 60.8 to HRC 61.6 when quenched at 1.060 to 1.1.0 ℃. Finely distributed carbides will exist in quenched microstructure, and effectively inhabit the growth of austenite grain. With the increasing of quenching temperature, the volume fraction of undis- solved carbides will decrease. The excellent comprehensive mechanical properties can be obtained by quenched at 1.060 to 1.1.0℃ with tempered at 1.0 to 1.0 ℃, and it is mainly due to the high carbon martensite and fine grain size. At these temperature ranges, the hardness will retain about HRC 59.2.to HRC 61.6 and the Charpy U-notch impact toughness will retain about 1..3 to 2. J. A lot of M2.C6 carbides precipitated from martensite matrix, at the same time along the boundaries of martensite lathes which leading to the decrease of impact toughness when tempered at 500 to 540 ℃. The maC precipitants also existed in the martensite mat

关键词： martensitic stainless steel microstructure mechanical property

Security Research on Engineering Database System

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厦门大学学报（自然科学版） 2002年第S1期41卷 288-289页

作者： REN jian-ping 1.2. SONG Han-tao 2. LIANG Yun-{1. 2.(1. North china institute of Technology, Taiyuan 030051. china 2. beijing institute of Technology, beijing 1.0081. china)

Engine engineering database system is an oriented C AD applied database management system that has the capability managing distributed data. The paper discusses the security issue of the engine engineering database management system (EDBMS). Through studying and analyzing the database security, to draw a series of securi ty rules, which reach B1. level security standard. Which includes discretionary access control (DAC), mandatory access control (maC) and audit. The EDBMS implem ents functions of DAC, maC and multigranularity audit. DAC solves the problems o f role inheritance, right contain, authorization identify and cascade revoke, et c; maC includes subject and object security setup rule, security modify rule and multilevel relation access operation rule, etc; Audit allows making the sub ject, object or operation type as different audit object to implement flexible a nd multigranularity audit method. The model is designed act as a security agent to access daemon database. At present, the model is implemented which runs on th e Windows 2.00 environments.

关键词： engineering database management system (EDBMS) s ecurity agent security level

Tuning Surface Molecular Design of Porous Carbon for Blue energy Harvesting

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Research 2024年第1期2023卷 651-662页

作者： jian Yu Zhong-Lin Wang Tianwei {1. Department of Civil and Environmental Engineering University of Hawaii at MānoaHonoluluHI 96822USA beijing {1. of Nano{2. and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Engineering Texas A&M University-Corpus ChristiCorpus ChristiTX 78412USA

Capacitive mixing is a promising blue energy technology due to its membrane-free electricity generation and long electrode life ***,because of limited perfor{1.nce,existing systems do not lend themselves to practical *** it is a crucial factor directly influencing electrode behavior,surface chemistry has largely been overlooked in capacitive ***,we show that {1.nipulating surface functionalization alone can tune the responses of electrodes to produce a high voltage rise without altering the pore structure of the *** findings reveal that the spontaneous electrode potential of a surface-modified carbon electrode shifts negatively proportional to the surface charge due to the surface groups,which explains why and how {1.nipulating the surface chemistry can improve the power generation capacity.

关键词： electrode Porous mixing

Correlation between the charge radii difference in mirror partner nuclei and thesymmetry energy slope

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Chinese Physics C 2024年第8期48卷 177-184页

作者： Xiao-rong {1. Shuai Sun rong An Li-Gang Cao School of Physics Ningxia UniversityYinchuan 750021China Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Key Laboratory of Beam Technology of Ministry of Education Institute of Radiation TechnologyBeijing Academy of Science and TechnologyBeijing 100875China

A correlation between the charge radii difference of mirror partner nucleiΔR_(ch) and the slope parameter L of symmetry energy has been built to ascertain the equation of state of isospin asymmetric nuclear *** this work,the influences of pairing correlations and isoscalar compression modulus on theΔRch are syste{1.tically investigated based on the Skyrme energy density functional *** calculated results suggest that the linear correlation betweenΔR_(ch) and L is decreased by the surface pairing *** slope parameter deduced from the difference of charge radii of mirror-pair nuclei ^(32.Ar-^(32.Si,^(36)Ca-^(36)S,^(38)Ca-^(38)Ar,and ^(54)Ni-^(54)Fe falls into the range of L=42.57−50.64 MeV,that is,the rather soft equation of state of asymmetric nuclear ***,the range of the slope parameter can also be influenced by the effective forces classified by various isoscalar incompressibility coefficients.

关键词： symmetry energy charge radius mirror-pair nuclei slope parameter

Unbound^(2.)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models

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Nuclear Science and Techniques 2024年第2期35卷 1-2页

作者： jian-Guo Li Bai-Shan Hu Shuang Zhang Fu-{1. Xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

The beyond-dripline oxygen isotopes^(2.,2.)O were recently observed at RIKEN,and were found to be unbound decaying into^(2.)O by emitting *** unbound feature of the heaviest oxygen isotope,^(2.)O,provides an excellent test for stateof-the-art nuclear *** atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N.

关键词： testing quantum system

Covalent triazine frameworks modified by ultrafine Pt nanoparticles for efficient photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 4908-4915页

作者： Xu Han Xueying Ge Wen-Wen He Wangwang Shen Tao Zhou jian-Sen Wang {1.-Lin Zhong Abdullah {2.l-Enizi Ay{2.n Nafady Shengqian {2. School of Chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China Department of Chemistry University of North Texas1508 W.Mulberry St.DentonTX 76201USA Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen *** this study,a Schottky heterojunction has been successfully constructed by evenly loading ultrafine PtNPs onto a triazine-based covalent organic frameworks(COFs).This strategy maintained the high activity of these ultra-small PtNPs while maximizing the utilization of the Pt active *** fabricated PtNPs@covalent triazine-based framework-1.CTF-1.composite accomplished a significantly high rate of hydrogen evolution(2..0 mmol·g^(−1.·h^(−1.,apparent quantum efficiency(AQE)=7.6%,atλ=450 nm)with 0.40 wt.%Pt loading,giving rise to a 44-fold-increase in the efficiency of the photocatalytic hydrogen production compared to the pristine *** calculations revealed that the strong electron transfer(Q(Pt)=−0.72. qe,in the analysis of Bader charge,Q(Pt)is the charge quantity transferred from Pt cluster to CTF-1.and qe is the unit of charge transfer quantity)between PtNPs and CTF-1.triggers a strong interaction,which makes PtNPs being firmly attached to the structure of CTF-1.thereby enabling high stability and excellent hydrogen production ***,the hydrogen binding free energy(ΔGH*)of PtNPs@CTF-1.is much lower than that of the unmodified CTF-1.leading to a much lower intermediate state and hence a significant improvement in photocatalytic *** overall findings of this work provide a new platform to incorporate metallic NPs into COFs for the design and fabrication of highly efficient photocatalysts.

关键词： Pt nanoparticles covalent triazine-based framework-1.CTF-1. photocatalysts hydrogen evolution reaction

market-based solution in {1. to finance the clean from the dirty

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Fundamental Research 2024年第2期4卷 324-333页

作者： Haoqi Qian rong {1. Libo Wu institute for Global Public Policy Fudan UniversityShanghai 200433China LSE-Fudan Research Centre for Global Public Policy Fudan UniversityShanghai 200433China School of Economics Fudan UniversityShanghai 200433China Shanghai institute for {1. and Carbon Neutrality Strategy Fudan UniversityShanghai 200433China

Financial incentives play a key role in promoting renewable energy investments that can help {1. achieve the‘dual carbon’*** national emissions trading scheme(ETS)and the renewable energy portfolio standard(RPS)ar... 详细信息

Financial incentives play a key role in promoting renewable energy investments that can help china achieve the‘dual carbon’*** national emissions trading scheme(ETS)and the renewable energy portfolio standard(RPS)are two existing market-based policy instruments that can generate stable expected returns for low-carbon *** paper studies the interactive distribution effects of these two market-based *** use the micro-level thermal power plant data to investigate the abatement effects of the national ETS,in which the details show that the existing rate-based ETS will result in higher negative impacts on power units,whose installed capacities are smaller than 400 *** interactive distribution effects between the two markets will occur when the permit allocation standards of the national ETS become stricter than the existing *** in Eastern china and Northern china will face high pressure on costs in both ETS and RPS *** the levels of the permit allocation standards are set as 70%of the existing ones and the carbon price is assumed to be 2.0 yuan/ton in 2.30,the annual market size of the national ETS will be nearly 100 billion yuan,and the annual market size is predicted to be 2.0 billion *** the existing rate-based national ETS,the china Certified Emission Reduction(CCER)mechanism will have an offsetting effect,which should be taken into serious consideration during the policy-making processes in the future.

关键词： Emission trading scheme Renewable energy portfolio standard Green finance Policy interactions china certified emission reduction Distribution effect

An improved pulse coupled neural networks model for semantic IoT

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Digital Communications and Networks 2024年第3期10卷 557-567页

作者： rong {1. Zhen Zhang Yide {1. Xiping Hu Edith C.H.Ngai Victor C.M.Leung School of Information Science and Engineering Lanzhou UniversityLanzhou 730000China School of Medical Technology Beijing Institute of TechnologyBeijing100081China Department of Electrical and Electronic Engineer The University of Hong KongHong Kong 999077China College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China Department of Electrical and Computer Engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada

In recent years,the Internet of Things(IoT)has gradually developed applications such as collecting sensory data and building intelligent services,which has led to an explosion in mobile data ***,with the rapid development of artificial intelligence,semantic communication has attracted great attention as a new communication ***,for IoT devices,however,processing image information efficiently in real time is an essential task for the rapid transmission of semantic *** the increase of model parameters in deep learning methods,the model inference time in sensor devices continues to *** contrast,the Pulse Coupled Neural Network(PCNN)has fewer parameters,making it more suitable for processing real-time scene tasks such as image segmentation,which lays the foundation for real-time,effective,and accurate image ***,the parameters of PCNN are determined by trial and error,which limits its *** overcome this limitation,an Improved Pulse Coupled Neural Networks(IPCNN)model is proposed in this *** IPCNN constructs the connection between the static properties of the input image and the dynamic properties of the neurons,and all its parameters are set adaptively,which avoids the inconvenience of manual setting in traditional methods and improves the adaptability of parameters to different types of *** segmentation results demonstrate the validity and efficiency of the proposed self-adaptive parameter setting method of IPCNN on the gray images and natural images from the matlab and Berkeley Segmentation *** IPCNN method achieves a better segmentation result without training,providing a new solution for the real-time transmission of image semantic information.

关键词： Internet of things(IoT) Semantic information Real-time application Improved pulse coupled neural network Image segmentation

Comprehensive tensile properties improved by deep cryogenic treatment prior to aging in friction-stir-welded 2.0}8 Al–Li alloy

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Rare Metals 2024年第10期43卷 5403-5409页

作者： jian-Qiu Sun Yue {1. Chong Gao Hong-Yun Luo School of materials Science and Engineering Beihang University chinalco Research {1. of Science and Technology

In order to improve the comprehensive mechanical properties,deep cryogenic treatment （DCT）prior to aging was carried out on friction-stir-welded（FSW） 2.0}8 Al-Li alloy;afterward,the microstructure and tensile properties were characterized by means of optical microscopy （OM）,transmission electron microscopy（TEM） and tensile *** results show that FSW 2.0}8 alloy through DCT prior to aging （DAT） possesses superior tensile properties than conventional aging treatment （AT）The microstructural analysis reveals that DAT alloy exhibits a finer grain structure,since DCT might effectively alleviate the residual stress in FSW 2.0}8 alloy and thus decrease the driving force for grain coarsening in subsequent aging ***,DCT generates dislocation multiplication,which provides more preferential nucleation sites for T1.（Al2.uLi） phase during subsequent aging treatment,resulting in high-density fine T1.phases and thin precipitate-free zone within DAT *** reasonable microstructure leads to DAT alloy possessing better strength-ductility combination compared to AT alloy.

关键词： Al–Li alloy Deep cryogenic treatment Friction stir welding Tensile properties