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Giant Birefringence in Layered Compound LaOBiS2

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Chinese Physics Letters 2014年第4期31卷 174-177页

作者： wang hai College of Materials Science and Engineering Tongji University Shanghai 201804

Birefringent crystals （BFCs） have been extensively used in imaging spectrometers, laser devices, and optical com- ponents. Seeking new BFCs is important for both fundamental research and industrial applications. Employing first-principles density functional theory, we find that LaOBiS2 （space group： P4/nmm） appearing in the parent phase of the recently discovered 13iS2-superconductor exhibits superior birefringence with a maximum value of 2.94, which is 13.4 times larger than the extensively used YV04 （0.22）. Furthermore, LaOBiS2 is an indirect semiconductor with a band gap of 0.9eV, which is suitgble for optical applications. The origin of giant inherent birefringence is also discussed.

关键词： LaOBiS_2 Giant parent

The miR156/SPL Module, a Regulatory Hub and Versatile Toolbox, Gears up Crops for Enhanced Agronomic Traits

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Molecular Plant 2015年第5期8卷 677-688页

作者： hai wang haiyang wang Biotechnology Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 China

In the past two decades, members of the SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE （SPL） family of transcription factors, first identified in Antirrhinum majus, have emerged as pivotal regulators of diverse biological processes in plants, including the timing of vegetative and reproductive phase change, leaf development, tillering/branching, plastochron, panicle/tassel architecture, fruit ripening, fertility, and response to stresses. Transcripts of a subset of SPLs are targeted for cleavage and/or translational repres- sion by microRNA156s （miR156s）. The levels of miR156s are regulated by both endogenous developmental cues and various external stimuli. Accumulating evidence shows that the regulatory circuit around the miR156/SPL module is highly conserved among phylogenetically distinct plant species, and plays impor- tant roles in regulating plant fitness, biomass, and yield. With the expanding knowledge and a mechanistic understanding of their roles and regulatory relationship, we can now harness the miR156/SPL module as a plethora of tools to genetically manipulate crops for optimal parameters in growth and development, and ultimately to maximize yield by intelligent design of crops.

关键词： agronomic trait crop miR156 SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL)

Phytochrome Signaling： Time to Tighten up the Loose Ends

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Molecular Plant 2015年第4期8卷 540-551页

作者： hai wang haiyang wang Biotechnology Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 China

Phytochromes are red and far-red light photoreceptors that play fundamental roles in controlling many aspects of plant growth and development in response to light. The past two decades have witnessed the mechanistic elucidation of the action mode of phytochromes, including their regulation by external and endogenous factors and how they exert their function as transcriptional regulators. More importantly, recent advances have substantially deepened our understanding on the integration of the phytochromemediated signal into other cellular and developmental processes, such as elongation of hypocotyls, shoot branching, circadian clock, and flowering time, which ofteninvolves complex intercellular and interorgan signaling. Based on these advances, this review illustrates a blueprint of our current understanding of phytochrome signaling and its crosstalk with other signaling pathways, and also points out still open questions that need to be addressed in the future.

关键词： light regulation light signaling cell signaling photomorphogenesis

Study on open charm hadron production and angular correlation in high-energy nuclear collisions

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Nuclear Science and Techniques 2021年第1期32卷 10-16页

作者： hai wang Jin-Hui Chen Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China

We study the production and angular correlationof charm hadrons in hot and dense matter produced in high-energy nuclear-nuclear collisions within a multiphasetransport model(AMPT).By triggering additional charm-anticharm quark pair production in the AMPT,the modeldescribes the D^0 nuclear modification factor in the low andintermediate pr regions in Au+Au collisions at√VSNN=200 GeV reasonably *** exploration of the D^0 pair azimuthal angular correlation for different centralitiesshows clear evolution from low-multiplicity to high-mul-tiplicity events,which is associated with the number ofcharm quark interactions with medium partons duringAMPT transport.

关键词： Heavy-ion collision Heavy flavor Nuclear modification factor Two-particle correlations

Anisotropy flows in Pb-Pb collisions at LHC energies from parton scatterings with heavy quark trigger

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Nuclear Science and Techniques 2022年第2期33卷 14-20页

作者： hai wang Jin-Hui Chen Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China

By implementing an additional heavy quark-antiquark pair production trigger in a multiphase transport(AMPT)model,we study the effect on anisotropy flows of identified particles with a focus on charged particles and quarkonium(J/ΨandΥ).A systematic increase in the collision rate for active partons in the AMPT model with such an implementation has been *** leads to a slight increase of identified particles anisotropy flows as a function of transverse momentum(pT)and rapidity,and gives a better description of the experimental data of elliptic flow toward larger *** approach provides an efficient way to study the heavy quark dynamics in the AMPT model at LHC energies.

关键词： Heavy-ion collision Quark-gluon plasma Quarkonium Collective flow

Study of white-light flares observed by Hinode

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Chinese Journal of Astronomy and Astrophysics 2009年第2期9卷 127-132页

作者： hai-Min wang Space Weather Research Lab Center for Solar Terrestrial Research New Jersey Institute of Technology Newark NJ 07102 USA

White-light flares are considered to be the most energetic flaring events that are observable in the optical broad-band continuum of the solar spectrum. They have not been commonly observed. Observations of white-light flares with sub-arcsecond resolution have been very rare. The continuous high resolution observations of Hinode provide a unique opportunity to systematically study the white-light flares with a spatial resolution around 0.2 arcsec. We surveyed all the flares above GOES magnitude C5.0 since the launch of Hinode in 2006 October. 13 of these kinds of flares were covered by the Hinode G-band observations. We analyzed the peak contrasts and equivalent areas （calculated via integrated excess emission contrast） of these flares as a function of the GOES X-ray flux, and found that the cut-off visibility is likely around M1 flares under the observing limit of Hinode. Many other observational and physical factors should affect the visibility of white-light flares; as the observing conditions are improved, smaller flares are likely to have detectable white-light emissions. We are cautious that this limiting visibility is an overestimate, because G-band observations contain emissions from the upper atmosphere. Among the 13 events analyzed, only the M8.7 flare of 2007 June 4 had near-simultaneous observations in both the G-band and the blue continuum. The blue continuum had a peak contrast of 94% vs. 175% in G-band for this event. The equivalent area in the blue continuum is an order of magnitude lower than that in the G-band. Very recently, Jess et al. studied a C2.0 flare with a peak contrast of 300% in the blue continuum. Compared to the events presented in this letter, that event is probably an unusual white-light flare： a very small kernel with a large contrast that can be detected in high resolution observations.

关键词： Sun activity - Sun flares - Sun magnetic fields

CPK-based grid authentication:a step forward

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 26-31页

作者： wang hai-yan School of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key Laboratory of Information Security Graduate School of Chinese Academy Beijing 100039 China School of Computer Science Suzhou University Suzhou 215006 China

Effective grid authentication plays a critical role in grid security, which has been recognized as a key issue in the designing and extension of grid technologies. At present, public key infrastructure （PKI） has been widely applied for grid authentication, and this article proposes a novel grid authentication mechanism, which is based on combined public key （CPK） employing elliptic curve cryptography （ECC）. The designing structure of the new grid authentication mechanism and its implementation procedure are described in details. Property analysis of the new mechanism is also made in comparison with that of the globus security infrastructure （GSI） authentication, which leads to the conclusion that CPK-based grid authentication, may be applied as an optimized approach towards efficient and effective grid authentication.

关键词： grid authentication CPK security

Characterization of hot deformation behavior of 30Si2MnCrMoVE low-alloying ultra-high-strength steel by constitutive equations and processing maps

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Journal of Iron and Steel Research International 2020年第7期27卷 807-819页

作者： hai wang Dong Liu Jian-guo wang hai-ping wang Yang Hu Hao-dong Rao School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an710072ShaanxiChina State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072ShaanxiChina

Isothermal compression tests of as-forged 30Si2MnCrMoVE low-alloying ultra-high-strength steel were carried out on a Gleeble 3500 thermal simulator at the deformation temperatures of 950-1150℃and strain rates of 0.01-10 s^−*** on the classical stress-dislocation density relationship and the kinematics of the dynamic recrystallization,the constitutive equations of the work hardening dynamical recovery period and dynamical recrystallization period were developed by using the work hardening curve and Avrami equation,which shows good agreement with the experimental *** maps at the strain of 0.90 were constructed based on dynamic material model and were analyzed combined with microstructure observation under different *** optimum parameter based on the processing maps was obtained and verified by a supplementary *** power dissipation maps and instability maps at strains of 0.05-0.90 were also constructed,and the evolution law was analyzed in *** established constitutive equation and hot processing maps can provide some guidance for hot working process.

关键词： 30Si2MnCrMoVE ultra-high-strength steel Hot deformation Constitutive model Processing map Power dissipation efficiency

New routes for the construction of strong metal-support interactions

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Science China Chemistry 2022年第11期65卷 2051-2057页

作者： hai wang Liang wang Feng-Shou Xiao Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Supported metal nanoparticles(NPs)on solid carriers are highly efficient catalysts in many industrial ***,the sintering and/or leaching of metal NPs occurred under harsh reaction conditions that caused the catalyst *** metal-support interactions(SMSIs)serve as an effective method to stabilize the metal NPs against sintering and leaching,which have been extensively *** addition to the classical route to construct SMSIs via high-temperature reduction treatments,new routes have emerged recently to extend the scope of catalysts with SMSIs and optimized their catalytic *** this review,we briefly summarize these routes that avoid the high-temperature reduction treatments for the construction of *** significant advantages in stabilizing metal NPs,modulating the geometric/electronic structure of metal species,and the mechanism on the SMSI formation are particularly ***,the current challenges and developing trends in the construction of SMSIs for achieving more efficient catalysts are outlooked.

关键词： strong metal-support interaction supported catalyst metal nanoparticles heterogeneous catalysis