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Multiwavelength Doppler factors for Fermi-detected gamma-ray loud blazars

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Research in Astronomy and Astrophysics 2011年第4期11卷 391-400页

作者： hou-Dun Zeng li Zhang Department of Physics Yunnan University Kunming 650091 China

We collect a sample of 51 Fermi-detected gamma-ray loud blazars with known radio Doppler factors and study properties of the Doppler factors of blazars at optical, X-ray and gamma-ray bands. A basic assumption is that the emission from the radio to gamma-ray bands of the blazars are produced by the nonthermal radiation of accelerated particles in a jet. Our results show that （1） the Doppler factors of blazars are a function of frequency, with the Doppler factor decreasing with frequency from the radio to X-ray regions, and then increasing from the X-ray to ,y-ray regions which are similar to results given by Zhang et al., and （2） there are marginal correlations between the Doppler factors at radio and X-ray bands and the synchrotron peak fre- quency, and a strong correlation between the Doppler factor in the gamma-ray band and the synchrotron peak frequency, but no correlation in the optical band.

关键词： galaxies active -- galaxies nuclei - galaxies jets -- radiation mecha-nisms non-thermal

Reverse genetics systems for SARS-CoV-2:Development and applications

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Virologica Sinica 2023年第6期38卷 837-850页

作者： hou-li Cai Yao-Wei Huang Department of Veterinary Medicine Zhejiang UniversityHangzhou310058China State Key Laboratory for Animal Disease Control and Prevention South China Agricultural UniversityGuangzhou510642China Guangdong Laboratory for lingnan Modern Agriculture College of Veterinary MedicineSouth China Agricultural UniversityGuangzhou510642China

The recent emergence of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)caused serious harm to human health and struck a blow to global economic *** on SARS-CoV-2 has greatly benefited from the use of reverse genetics systems,which have been established to artificially manipulate the viral genome,generating recombinant and reporter infectious viruses or biosafety level 2(BSL-2)-adapted non-infectious replicons with desired *** tools have been instrumental in studying the molecular biological characteristics of the virus,investigating antiviral therapeutics,and facilitating the development of attenuated vaccine ***,we review the construction strategies,development,and applications of reverse genetics systems for SARS-CoV-2,which may be applied to other CoVs as well.

关键词： SARS-CoV-2 Reverse genetics systems Infectious clones Replicons live attenuated vaccines

SiC/Si-W-Mo coating for protection of C/C composites at 1873 K

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Journal of University of Science and Technology Beijing 2008年第6期15卷 822-826页

作者： Dangshe hou Kezhi li Hejun li Qiangang Fu Yulei Zhang National Key Laboratory of Thermostructure Composite Materials Northwestern Polytechnical University Xi＇an 710072 China

In order to prevent carbon/carbon composites from oxidation at 1873 K, an efficient oxidation protective SiC/Si-W-Mo coating was prepared by a two-step pack cementation technique. The microstructures and the phase composition of the as-received multi-coating were examined by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. It is seen that the compact multi-coating is composed of α-SiC, Si, and （WxMO1-x）Si2. Oxidation test shows that, after oxidation at 1873 K in air for 102 h and thermal cycling between 1873 K and room temperature for 10 times, the weight loss of the SiC/Si-W-Mo coated C/C composites is only 0.26%. The invalidation of the multi-coating is attributed to the formation of penetrable cracks in the coating. 2008 University of Science and Technology Beijing. All rights reserved.

关键词： C/C composites coating microstructure oxidation protection

Investigating Ion Transport through Artificial Transmembrane Channels Containing Introverted Groups

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Chinese Journal of Chemistry 2022年第11期40卷 1293-1297页

作者： Ya-Wei li Yong-Hong Fu Jun-li hou Department of Chemistry Fudan University220 Handan RoadShanghai 200433China

The investigation on the relationship between structure and transport activity of artificial transmembrane channels has still re-mained a challenge because of lacking strategy to precisely arrange the functional group in the channel ***,we report a general strategy to monitor ion transport through the artificial channels by using unimolecular tubular molecules containing intro-verted *** found that the ion transport rate decreased with elongation of the introverted sidechains and the channel with propyl group as the introverted sidechain exhibited the longest opening duration ***,we have revealed that,comparing to the ion transport rate,the opening duration is a more important factor for determining the transport activity of the artificial channels.

关键词： Supramolecular chemistry Self-assembly Nanostructures Artificial transmembrane channels Pillararene

Optical enhanced interferometry with two-mode squeezed twin-Fock states and parity detection

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Chinese Physics B 2020年第3期29卷 202-208页

作者： li-li hou Shuai Wang Xue-Fen Xu School of Mathematics and Physics Jiangsu University of TechnologyChangzhou 213001China Department of Fundamental Courses Wuxi Institute of TechnologyWuxi 214121China

We theoretically investigate the quantum enhanced metrology using two-mode squeezed twin-Fock states and parity detection. Our results indicate that, for a given initial squeezing parameter, compared with the two-mode squeezed vacuum state, both phase sensitivity and resolution can be enhanced when the two-mode squeezed twin-Fock state is considered as an input state of a Mach–Zehnder interferometer. Within a constraint on the total photon number, although the two-mode squeezed vacuum state gives the better phase sensitivity when the phase shift φ to be estimated approaches to zero, the phase sensitivity offered by these non-Gaussian entangled Gaussian states is relatively stable with respect to the phase shift itself. When the phase shift slightly deviates from φ= 0, the phase sensitivity can be still enhanced by the two-mode squeezed twin-Fock state over a broad range of the total mean photon number where the phase uncertainty is still below the quantum standard noise limit. Finally, we numerically prove that the quantum Cramer–Rao bound can be approached with the parity detection.

关键词： quantum optics phase sensitivity quantum metrology

Numerical Simulation of Microstructure Formation and Forecast of Mechanical Properties for Spheroidal Graphite Iron

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Journal of Materials Science & Technology 2003年第Z1期19卷 13-16页

作者： Weimin ZHAO Shuping hou Haipeng li Aiwen HU School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132 China Tianjin Commercial University 300400 China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132 China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132 China

The numerical simulation can overcome the hardship of mathematical analysis and experimental research, explicate the mechanism of microstructure shaping, predict mechanical properties and operating life of castings and then optimize technology and control microstructure formation to obtain the qualified castings. The finite difference method (FDM) is applied to the simulation of temperature field based on all kinds of nucleation and growth models on all stages of solidification of spheroidal graphite cast iron. Visual C++ is used to program the numerical simulation software, QTstructure-1 to simulate the solidification process of spheroidal graphite cast iron and the formation of all phases in solidification process. Finally, the result of simulation is well agreed with the experimental result.

关键词： Spheroidal graphite iron, Numerical simulation, Finite difference method, Temperature field

Pillar[n]arenes: Chemistry and Their Material Applications

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Chinese Journal of Chemistry 2020年第2期38卷 215-217页

作者： Harekrushna Behera Lu Yang Jun-li hou Department of Chemistry Fudan University220 Handan RoadShanghai 200433China Department of Chemistry Western UniversityLondonOntarioCanada

Background Pillar[n]arene(PA[n])contains a symmetrical structures,where para-bridge connection between the units looks like a column-like or pillar shape and polygonal structure from side and top views,*** attached gr... 详细信息

关键词： attached directions opposite

Preparation of SGO-modified nanofiltration membrane and its application in SO_4^(2-) and Cl^- separation in salt treatment

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Journal of Environmental Sciences 2019年第4期31卷 183-192页

作者： Yanjun Zhang Changwei Zhao Shaofeng Zhang ling Yu Jiding li li-an hou School of Chemical Engineering Hebei University of Technology Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua University Xi'an High-Tech Institute

The lack of fresh water in the world makes the search for an effective method to decontaminate water an urgent *** important step is to remove different multivalent ions in salt ***(NF)has been used for treating water containing different kinds of *** this work,sulfonate group-modified graphene oxide(SGO)was prepared,and added during the interfacial polymerization(IP)reaction to prepare SGO-modifiedNF membranes(PA-SGO).The chemical composition,structure and surface properties of PA and PA-SGO membranes were characterized by FT-IR,XPS,SEM,AFM,contact angle and zeta potential *** water flux,salt rejection and antifouling abilities were investigated *** testing results showed that the water flux of PA-SGO(0.03%SGO)was 45.85 LMH under a pressure of 0.2 MPa,and the salt rejection varied in the order of Na_2SO_4(98.99%)>MgSO_4(91.25%)>MgCl_2(42.27%)>NaCl(21.96%).An anti-fouling experiment indicated that the PA-SGO membrane had good anti-fouling properties because of its decreased roughness and increased hydrophilicity and *** PA-SGO membrane has good potential for use in removing salt ions from water.

关键词： Water treatment Sulfonate group-modified graphene oxide NF Membrane Salt separation

Hydrogen Sulfide May Function Downstream of Nitric Oxide in Ethylene-Induced Stomatal Closure in Vicia faba L.

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Journal of Integrative Agriculture 2012年第10期11卷 1644-1653页

作者： liU Jing hou Zhi-hui liU Guo-hua hou li-xia liU Xin Key Laboratory of Plant Biotechnology in Universities of Shandong Province/College of life Science Qingdao Agricultural University

Pharmacological, laser scanning confocal microscopic （LSCM）, and spectrophotographic approaches were used to study the roles of hydrogen sulfide （H2S） and nitric oxide （NO） in signaling transduction of stomatal movement in response to ethylene in Viciafaba L. Ethylene treatment resulted in the dose-dependent stomatal closure under light, and this effect was blocked by the inhibitors of H2S biosynthesis in V. faba L. Additionally, ethylene induces H2S generation and increases L-/D-cysteine desulfhydrase （pyridoxalphosphate-dependent enzyme） activity in leaves of V. faba L. Inhibitors of H2S biosynthesis have no effect on the ethylene-induced stomatal closure, NO accumulation, and nitrate reductase （NR） activity in guard cells or leaves of II. faba L. Moreover, the ethylene-induced increase of H2S levels and L-/D- cysteine desulfhydrase activity declined when NO generation was inhibited. Therefore, we conclude that H2S and NO probably are involved in the signal transduction pathway of ethylene-induced stomatal closure. H2S may represent a novel component downstream of NO in the ethylene-induced stomatal movement in V. faba L.

关键词： hydrogen sulfide nitric oxide ethylene stomatal closure Vicia faba L.