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Dynamic and Static Recrystallization Behaviour of Coarse-grained Austenite in a Nb-V-Ti Microalloyed Steel

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Journal of Iron and Steel Research International 2014年第2期21卷 233-239页

作者： Qing-yun sha Da-hang li Gui-yan li Technology Center Angang Steel Company Limited

The dynamic recrystallization （DRX） and static recrystallization （SRX） behaviour of coarse-grained aus- tenite in a Nb-V-Ti microalloyed steel were studied by using a Gleeble thermomechanical simulator. Continuous and interrupted compression tests of coarse-grained austenite were performed in the temperature range of 1000-1 150 ℃ at a strain rate of 0. 1- 5 s 1. The peak and critical strains for the onset of DRX were identified with strain hardening rate analysis, and the ratio of critical strain to peak strain was found to be consistent with the one reported for fine- grained austenite. An equation of the time for 50% softening was proposed by considering the activation energy of steel without microalloying elements and the solute drag effect of microalloying elements. Strain-induced precipitation may not take place at the deformation temperature above 1000 ℃, which indicates that SRX of coarse-grained aus- tenite is mainly retarded by coarse grain size and Nb in solution during rough rolling.

关键词： coarse-grained austenite dynamic recrystallization static recrystallization critical strain time for 50%softening

Landscape influences and management countermeasures of ginseng planting near Changbai mountain nature reserve

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Journal of Forestry Research 2022年第6期33卷 1939-1948页

作者： Mingfang Tang sha Qiu lijie liu Tao li shanlin li Tianshu Yu State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Jilin Provincial Joint Key Laboratory of Changbai Mountain Biocoenosis and Biodiversity Changbai Mountain Academy of Science133613YanbianJilinPeople’s Republic of China National Science library Chinese Academy of SciencesBeijing 100190People’s Republic of China

Ginseng planting in Northeast China brings economic benefits but affects forest landscape integrity and native ecological *** order to quantify the impacts of ginseng planting on the forest landscape,Fusong County in Jilin Province was selected as a study *** number and distribution of ginseng fields over different time was quantified based on remote sensing and ground *** analysis and multiple regression analysis were used to study the impacts of ginseng planting on the *** results showed that altitudes and slopes of ginseng fields increased and became increasingly scattered and smaller closer to the Changbai Mountain Nature *** fields and abandoned fields increased total patches and total area of the local forested landscape,and shared edge lengths between ginseng fields and forests,resulting in continuous fragmentation of the *** the total area of existing and abandoned ginseng fields accounts for a small fraction of the total landscape,their negative impacts on ecosystem conservation is *** local government needs to rationally plan ginseng planting,scientifically implement the restoration of abandoned ginseng lands,and enhance awareness of ginseng farmers to environmental *** study has important significance for maintaining the healthy and stable development of the local ginseng industry and for improving the quality of regional ecological environment.

关键词： Ginseng planting Agroforestry system Land use Landscape fragmentation Forest degradation Changbai Mountain Nature Reserve

The Arabidopsis R-SNARE protein YKT61 is essential for gametophyte development

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Journal of Integrative Plant Biology 2021年第4期63卷 676-690页

作者： Ting Ma En li Lu-Shen li sha li Yan Zhang State Key laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTai'an 271018China

Gametophyte development is a pre-requisite for plant reproduction and seed yield;therefore,studies of gametophyte development help us understand fundamental biological questions and have potential applications in *** biogenesis and dynamics of endomembrane compartments are critical for cell survival,and their regulatory mechanisms are just beginning to be ***,we report that the Arabidopsis thaliana SNARE(soluble N-ethylmaleimide sensitive factor attachment protein receptor)protein YKT61 is essential for both male and female *** using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-based genome editing,we demonstrated that male and female gametophytes carrying YKT61 loss-offunction alleles do not ***,loss of YKT61 function resulted in the arrest of male gametophytic development at pollen mitosis I and the degeneration of female gametophytes.A three-base-pair deletion in YKT61 in the ykt61-3 mutant resulted in a single-amino acid deletion in the longin domain of YKT61;the resulting mutant protein does not interact with multiple SNAREs and showed substantially reduced membrane association,suggesting that the N-terminal longin domain of YKT61 plays multiple roles in its *** study demonstrates that Arabidopsis YKT61 is essential for male and female gametogenesis and sets an example for functional characterization of essential genes with the combination of Cas9-mediated editing and expression from a Cas9-resistant transgene.

关键词： Arabidopsis ametogenesis embryo sac pollen pollen tube attraction SNARE

Alternative non-Gaussianity measures for quantum states based on quantum fidelity

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Chinese Physics B 2022年第3期31卷 192-200页

作者： Cheng Xiang shan-shan li sha-sha Wen shao-Hua Xiang College of Electrical and Information Engineering Huaihua UniversityHuaihua 418008 China Hunan Provincial Key Laboratory of Ecological Agriculture Intelligent Control Technology Huaihua 418008China

We propose three alternative measures for non-Gaussianity of quantum states: sine distance, Bures angle, and Bures distance, which are based on quantum fidelity introduced by Wang [Phys. Lett. A 373 58(2008)]. Using them, we evaluate the non-Gaussianity of some relevant single-mode and two-mode non-Gaussian states and find a good consistency of the three examined measures. In addition, we show that such metrics can exactly quantify the degree of Gaussianity of even Schrödinger-cat-like states of small amplitudes that can not be measured by other known non-Gaussianity measures such as the Hilbert–Schmidt metric and the relative entropy metric. We make a comparative study between all existing nonGaussianity measures according to the metric axioms and point out that the sine distance is the best candidate among them.

关键词： non-Gaussianity quantum fidelity non-Gaussian states sine metric

Comparison of sea surface wind field measured by HY-2A scatterometer and WindSat in global oceans

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Journal of Oceanology and limnology 2019年第1期37卷 38-46页

作者： ZHENG Minwei li Xiao-Ming sha Jin Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences University of Chinese Academy of Sciences Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology Hainan Key Laboratory of Earth Observation

In this study, we present a comprehensive comparison of the sea surface wind ?eld measured by scatterometer(Ku-band scatterometer) aboard the Chinese HY-2 A satellite and the full-polarimetric radiometer WindSat aboard the Coriolis satellite. The two datasets cover a four-year period from October2011 to September 2015 in the global oceans. For the sea surface wind speed, the statistical comparison indicates good agreement between the HY-2 A scatterometer and WindSat with a bias of nearly 0 m/s and a root mean square error(RMSE) of 1.13 m/s. For the sea surface wind direction, a bias of 1.41° and an RMSE of 20.39° were achieved after excluding the data collocated with opposing directions. Furthermore,discrepancies in sea surface wind speed measured by the two sensors in the global oceans were *** is found that the larger dif ferences mainly appear in the westerlies in the both hemispheres. Both the bias and RMSE show latitude dependence, i.e., they have signi?cant latitudinal ?uctuations.

关键词： sea surface wind feld global comparisons HY-2A scatterometer polarimetric radiometer WindSat

A Web-like Three-dimensional Binder for Silicon Anode in lithium-ion Batteries

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Energy & Environmental Materials 2024年第1期7卷 21-27页

作者： liyuan li Tao li Yifan sha Baozeng Ren Lan Zhang Suojiang Zhang CAS Key Laboratory of Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Langfang Green Industrial Technology Center Langfang 065001China Henan Key Laboratory of Energy Storage Materials and Processes Zhengzhou Institute of Emerging Industrial TechnologyZhengzhou 450003China

Si anode is of paramount importance for advanced energy-dense lithium-ion batteries(liBs).However,the large volume change as well as stress generates during its lithiation-delithiation process poses a great challenge to the long-term cycling and hindering its *** this work,a composite binder is prepared with a soft component,guar gum(GG),and a rigid linear polymer,anionic polyacrylamide(APAM).Rich hydroxy,carboxyl,and amide groups on the polymer chains not only enable intermolecular crosslinking to form a web-like binder,A2G1,but also realize strong chemical binding as well as physical encapsulating to Si *** resultant electrode shows limited thickness change of merely 9%on lithiation and almost recovers its original thickness on *** demonstrates high reversible capacity of 2104.3 mAh g^(-1)after 100 cycles at a current density of 1800 mA g^(-1),and in constant capacity(1000 mAh g^(-1))test,it also shows a long life of 392 ***,this soft-hard combining web-like binder illustrates its great potential in the future applications.

关键词： anionic polyacrylamide lithium-ion batteries Si anode thickness change web-like binder

Hydrothermal Synthesis and Crystal Structure of a Cd^(2+) Supramolecular Coordination Complex{[Cd_2(HCAM)_2(H_2O)_4]·3.5H_2O}_n with a 3D Metal-organic Open Framework

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1067-1071页

作者： ZHOU Qiu-Xiang li sha-sha WANG Meng BAI Xiao-Jie Langfang Teachers College Langfang 065000 China College of Chemical Engineering and Technology Hebei University of Technology Tianjin 300130 China

A three-dimensional coordination polymer {[Cd2（HCAM）2（H2O）4].***2O}n was synthesized by the hydrothermal reaction of H3CAM （H3CAM = 4-hydroxypyridine-2,6-dicerboxylic acid） and Cd（NO3）2·4H2O. The structure was characterized by elemental analysis, thermal gravimetric analysis, infrared spectroscopy and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 9.4389（19）, b = 11.009（2）, c = 11.192（2） A, α = 87.87（3）, β= 74.63（3）, γ = 81.22（3）°, V= 1108.2（4） A3, Z = 2, Dc= 2.164 g/cm3,μ = 2.011 mm^-1, F（000） = 710, R = 0.0419 and wR = 0.1170. X-ray analysis reveals that the title compound adopts a one-dimensional staircase structure by carboxyl of H3CAM and water molecules, and it is further linked by hydrogen bonds to form a 3-D metal-organic open framework. The thermal gravimetric analysis displays that the framework exists stably below 300 ℃.

关键词： hydrothermal synthesis 3D coordination polymer crystal structure

Engineering of Ag@Pd/Al_(2)O_(3)with varied Pd-shell thickness:Dynamic evolution of ligand and strain effects on acetylene selective hydrogenation

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Chinese Journal of Chemical Engineering 2023年第12期64卷 139-148页

作者： Mingbo Yang Tianxing Yang Rui Ma sha li Yufei He Dianqing li State Key Laboratory of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Medicine and Chemical Engineering Lianyungang Technical CollegeLianyungang 222006China Chemistry and Chemical Engineering Guangdong Laboratory Shantou 515031China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou 324000China Beijing Engineering Center for Hierarchical Catalysts Beijing University of Chemical TechnologyBeijing 100029China

Bimetallic nanoparticles exhibit a synergistic effect that critically depends on their surface composition,but such promotion mechanisms become vague with varying surface ***,alumina supported Ag@Pd core–shell and PdAg alloy structure with controlled size and surface compositions were prepared to demonstrate synergetic mechanisms,particularly,ligand and strain effects on activity and ethylene selectivity for acetylene *** performance evaluation indicates that Ag@Pd catalysts with well-controlled Pd-shell thickness can effectively lower apparent activation energy and improve ethylene *** activity increases from 0.019 to 0.062 s^(-1) with decreasing Pd-shell thickness under mild conditions,which is 3–6 times higher than their alloyed and monometallic *** characterizations and density functional theory are conducted to reveal such shell-thickness-dependent *** ligand effect arising from Ag alloying in the interface of Ag@Pd2ML observes the strongest binding of acetylene,but it diminished sharply and the strain effect gets more prevailing with increasing shell *** competition of ethylene desorption and deephydrogenation were also investigated to understand the selectivity governing factors,and the selectivity descriptor(0.5BE(C_(2)H_(4))–BE(H))was built to match the contribution of ligand and strain effect on the different surfaces of Pd-Ag bimetallic *** exploration of synergetic mechanisms among bimetallic NPs with varied structure and surface compositions in this work can help us to deepen the understanding catalyst structure–activity relationship and provide a feasible way to optimize the overall catalytic performance.

关键词： Catalyst Hydrogenation Nanostructure Shell-thickness-dependent performance ligand and strain effect

Construction of Protograph LDPC Codes Based on the Convolution Neural Network

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China Communications 2023年第5期20卷 84-92页

作者： Zhiyuan Xiao liguang li Jin Xu Jin sha School of Electronic Science and Engineering Nanjing UniversityNanjing 210023China Institute of Wireless Research ZTE CorporationShenzhen 518055China

This paper presents an intelligent protograph construction *** LDPC codes have shown excellent error correction performance and play an important role in wireless *** search or manual construction are often used to obtain a good protograph,but the efficiency is not high enough and many experience and skills are *** this paper,a fast searching algorithm is proposed using the convolution neural network to predict the iterative decoding thresholds of protograph LDPC codes effectively.A special input data transformation rule is applied to provide stronger generalization *** proposed algorithm converges faster than other *** iterative decoding threshold of the constructed protograph surpasses greedy algorithm and random search by about 0.53 dB and 0.93 dB respectively under 100 times of density *** results show that quasi-cyclic LDPC(QC-LDPC)codes constructed from the proposed algorithm have competitive performance compared to other papers.

关键词： LDPC codes protograph codes iterative decoding threshold neural network