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Stability of Retained Austenite Through a Combined Intercritical Annealing and Quenching and Partitioning(IAQP) Treatment

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 386-393页

作者： Ri-Ming Wu Wei Li Cheng-Lin Wang Yi Xiao Li Wang Xue-jun jin School of Materials Science and Engineering Shanghai Jiao Tong University School of Materials Science and Engineering Shanghai University State Key Lab of Development and Application Technology of Automotive Steels Baosteel Research Institute

Intercritical annealing（IA） at various temperatures followed by quenching and partitioning（IAQP） treatments was conducted on a cold-rolled Fe-0.2C-1.42Si-l.87Mn（wt%） sheet *** microstructure and enhanced mechanical properties were achieved through appropriate adjustment of IA *** steel which was annealed at1,033 K for 600 s,then quenched to 573 K and partitioned at 693 K for 20 min,designated as 1033 QP steel,exhibits maximum 16.3 vol% retained austenite（RA） with good mechanical properties（ultimate tensile strength 886 MPa and total elongation 27%）.It was found that the thermal and mechanical stabilities of RA are mainly influenced by the combined effect of its average carbon content and amount of adjacent ***,the transformation-induced plasticity effect increased the peak n-values observed at the second stage of the work hardening of IAQP steels.

关键词： Intercritical annealing and quenching and partitioning treatment(IAQP) Retained austenite(RA) Average carbon content(ACC) Amount of adjacent martensite(AAM) Transformation-induced plasticity(TRIP)

Viscous creep of ice-rich permafrost debris in a recently uncovered proglacial area in the Tianshan Mountains, China

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Advances in Climate Change Research 2022年第4期13卷 540-553页

作者： Yu ZHOU Guo-Yu LI Hui-jun jin Sergey SMARCHENKO Wei MA Qing-Song DU jin-Ming LI Dun CHEN State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Da Xing'anling Observation and Research Station of Frozen-ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJagdaqi 165000China School of Civil Engineering and Institute of Cold Regions Science and Engineering Northeast Forestry UniversityHarbin 150040China Geophysical Institute University of Alaska FairbanksFairbanksAK 99775USA

Since the Little Ice Age and as a consequence of climate warming,many recently deglaciated forefields have become and will continue to evolve into large ice-debris complexes exposed to periglacial processes and *** transitional processes have significant implications for geomorphologic shaping and water supply for the downstream communities,especially in arid regions,but our understanding of their evolutionary processes and their potential geomorphic and hydrological impacts is stil limited.A landform transition from partly debris-covered glaciers to ice-rich permafrost debris undergoing slow viscous creep was revealed in the Aerzailaikunai Valley in the eastern Tianshan Mountains in China based on the results of in-situ observations and measurements(boreholes,ground temperature monitoring,electrical resistivity tomography surveys,and continuous global positioning system measurements,among others).The internal structure of ice-tll mixture contains pure ice layers,supersaturated frozen sands with ice lenses,and ice-bearing blocks with maximum volumetric contents of heterogeneous ice at 35%-60%.Beneath an 1.5-m-thick active layer,permafrost reached far into the underlying bedrock with the mean annual ground temperature of-2.1℃ at the depth of 20 *** higher surface velocities(with an accumulative displacement of 65 mm from October 2019 to May 2020)and extremely high electrical resistivity(several million Ω m)of the debris-covered glacier margin were in sharp contrast to those of the progressively stabilizing ground surface(up to 16 mm)and the lower zones with relatively smaler electrical resistivity(several thousand Ω m).Combined with the borehole stratigraphy(higher rock content),monitored ground temperatures(permafrost environment),lower electrical resistance(ice-rich moraine),and continuous global positioning system results(viscous creeping),this study documents a transition from glacial to periglacial conditions,materials and processes characteristic

关键词： Alpine permafrost Viscous creep Debris-covered glacier margins Climate warming Landform transition Evolution of rock glacier

Exponential stability and periodic solution for fuzzy BAM Neural networks with time varying delays

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 157-166页

作者： XIANG Hong-jun WANG jin-hua Department of Mathematics, Xiangnan University, Chenzhou 423000, China Department of Mathematics Xiangnan University Chenzhou 423000 China

In this paper, a class of fuzzy BAM neural networks with time varying delays is discussed. By using the properties of M-matrix, Linear Matrix Inequality（LMI） approach and general Lyapunov-Krasovskii functional, some new sufficient conditions are derived to ensure the existence of periodic solutions and the global exponential stability of the fuzzy BAM neural networks with time varying delays. These results have important significance in the design of global exponential stable BAM networks with delays. Moreover, an example is given to illustrate that the conditions of the results in the paper are feasible.

关键词： fuzzy BAM neural network periodic solution exponential stability linear matrix inequality(LMI) Lyapunov-Krasovskii functional

Characterization of the voltage-gated sodium channel of the Asian citrus psyllid, Diaphorina citri

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Insect Science 2017年第1期24卷 47-59页

作者： Bin Liu Monique R. Coy jin-jun Wang Lukasz L. Stelinski Entomology and Nematology Department Citrus Research and Education Center University of Florida Florida USA Key Laboratory of Entomology and Pest Control Engineering College of Plant Protection Southwest University Chongqing China

The Asian citrus psyllid, Diaphorina citri Kuwayama （Hemiptera： Liviidae）, is an important insect pest of citrus. It is the vector of ＇Candidatus＇ Liberibacter asiaticus, a phloem-limited bacterium that infects citrus, resulting in the disease Huanglongbing （HLB）. Disease management relies heavily on suppression of D. cirri populations with insecticides, including pyrethroids. In recent annual surveys to monitor insecticide resistance, reduced susceptibility to fenpropathrin was identified in several field populations olD. citri. The primary target ofpyrethroids is the voltage-gated sodium channel （VGSC）. The VGSC is prone to target-site insensitivity because of mutations that either reduce pyrethroid binding and/or alter gating kinetics. These mutations, known as knockdown resistance or kdr, have been reported in a wide diversity of arthropod species. Alternative splicing, in combination with kdr mutations, has been also associated with reduced pyrethroid efficacy. Here we report the molecular characterization of the VGSC in D. citri along with a survey of alternative splicing across developmental stages of this species. Previous studies demonstrated that D. citri has an exquisite enzymatic arsenal to detoxify insecticides resulting in reduced efficacy. The results from the current investigation demonstrate that target-site insensitivity is also a potential basis for insecticide resistance to pyrethroids in D. citri. The VGSC sequence and its molecular characterization should facilitate early elucidation of the underlying cause of an established case of resistance to pyrethroids. This is the first characterization of a VGSC from a hemipteran to this level of detail, with the majority of the previous studies on dipterans and lepidopterans.

关键词： citrusgreening diseasemanagement knockdownresistance(kdr) target-site insensitivity

Modified reward function on abstract features in inverse reinforcement learning

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第9期11卷 718-723页

作者： Shen-yi CHEN Hui QIAN Jia FAN Zhuo-jun jin Miao-liang ZHU School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

We improve inverse reinforcement learning(IRL) by applying dimension reduction methods to automatically extract Abstract features from human-demonstrated policies,to deal with the cases where features are either unknown or *** importance rating of each abstract feature is incorporated into the reward *** is performed on a task of driving in a five-lane highway,where the controlled car has the largest fixed speed among all the *** is almost 10.6% better on average with than without importance ratings.

关键词： Importance rating Abstract feature Feature extraction Inverse reinforcement learning(IRL) Markov decision process(MDP)

A facile synthesis of cyano-chlorins related to chlorophyll from formyl (pyro)-pheophorbide-a by a tandem transformation of the aldehyde into a nitrile group

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Chinese Chemical Letters 2016年第5期27卷 789-794页

作者： Na Gao Jia-Zhu Li Yan-Long Li Zhen Wang jin-jun Wang Department of Food & Biological Engineering Wenjing College Yantai University College of Chemistry and Chemical Engineering Yantai University

A facile synthesis for cyanochlorin related to chlorophyll from a formyl-substituted chlorin, by the oxidation of methyl （pyro）pheophorbide-a, was accomplished. These readily available chlorin aldehydes were assembled together with hydroxylamine hydrochloride in a tandem process to produce the corresponding chlorin nitriles in moderate to good yields. The formation of chlorin nitrile was discussed and a possible mechanism for the corresponding cyanation reaction was tentatively proposed.

关键词： Chlorophyll-α Chlorin(Pyro)pheophorbide-α Cyanation reaction Beckmann rearrangement Tandem transformation

Improving hydrogen embrittlement resistance of a modified press hardening steel by introducing retained austenite as hydrogen trap

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Journal of Iron and Steel Research International 2022年第11期29卷 1864-1872页

作者： Wei Ding Kai Yang Yu Gong Li Wang Ji-yao Hong Wei Li Xue-jun jin Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiao Tong UniversityShanghai 200240China Institute of Advanced Steels and Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Development and Application Technology of Automotive Steels BaoSteel Research InstituteShanghai 201900China

The effect of retained austenite(RA)with higher mechanical stability on hydrogen embrittlement resistance of a modified 22MnB5(C 0.22,Si 0.8,Mn 1.5,B 0.002,Fe balance,in wt.%)press hardening steel(PHS)has been ***-step quenching and partitioning(Q&P)treatment was applied to PHS,and around 6 vol.%ultra-fine RA was *** ultra-fine RA was found to act as stronger hydrogen trap than dislocations and grain boundaries in martensitic matrix and can decrease the apparent diffusion coefficient of hydrogen from 5.97×10^(-7) to 3.83×10^(-7) cm^(2) s^(-1),which was verified by the combination of thermal desorption spectroscopy analysis and hydrogen permeation *** higher mechanical stability of the ultrafine RA assures enough stability of the hydrogen trap,which results in better hydrogen embrittlement resistance in Q&P-treated PHS than the conventional directly quenched PHS.

关键词： Hydrogen embrittlement Press hardening steel Quenching and partitioning Retained austenite Thermal desorption spectroscopy Hydrogen permeation

The Total Synthesis of (±)-Hinesol and (±)-Agarospirol

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Chinese Chemical Letters 1997年第11期8卷 957-960页

作者： jin jun WANG Chang jin YUE jun QIU (Department Of Fine Chemistry, Jilin Chemical Engineering College, Jilin, 132002)Cang Yi QIAN(Department of Chemistry, Qing Hua University, Beijing, 100084) Department of Fine Chemistry Jilin Chemical Engineering College Jilin 132002 China Department of Chemistry Qing Hua University Beijing 100084 China

A mild base-catalyzed retro-benzilic acid rearrangement of a proto-[2+2]photocycloadduct, formed in highly steroselective photoaddition of methyl 2,4-dioxo-pentanoate to 1,5-dimethyl-6-methylenecyclohexene, afforded a spiro[4, 5] decenedione from which hinesol and agarospirol were synthesized by means of reductive elimination of α-diketone and C1-homologation.

关键词： The Total Synthesis of Hinesol and Agarospirol

Observational constraints on running vacuum model

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Chinese Physics C 2019年第2期43卷 132-137页

作者： jin-jun Zhang Chung-Chi Lee Chao-Qiang Geng School of Physics and Information Engineering Shanxi Normal University DAMTP Centre for Mathematical Sciences University of Cambridge Department of Physics National Tsing Hua University National Center for Theoretical Sciences

We investigate the power spectra of the CMB temperature and matter density in the running vacuum model(RVM) with the time-dependent cosmological constant of A=3 vH^2+ Λ_0, where H is the Hubble parameter. In this model, dark energy decreases in time and decays to both matter and radiation. By using the Markov chain Monte Carlo method, we constrain the model parameter v as well as the cosmological observables. Explicitly, we obtain v ≤1.54× 10^(-4)(68% confidence level) in the RVM with the best-fit χ_(RVM)~2 =13968.8, which is slightly smaller thanχ_(ΛCDM)~2= 13969.8 in the ΛCDM model of v = 0.

关键词： matter power spectrum running vacuum model CMB temperature spectrum cosmological constant