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Experimental investigations on the strategies of fighting crickets Velarifictorus micado to manipulate air resistance

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Science China(Physics,Mechanics & Astronomy) 2020年第6期63卷 54-65页

作者： yun xing JiaLing Yang Institute of Solid Mechanics Beihang UniversityBeijing 100191China

Fighting crickets,one species of flightless insects optimally chosen by nature for millions of years,have evolved to fairly smooth and streamlined body *** article tries to answer the question how the insects manipulate air resistance when travelling through air after take-off without using their wings and meanwhile keep a high *** found that fighting crickets,Velarifictorus micado,performed two types of movements through air:stable and *** two types both have a high moving *** the stable type,the moving efficiency is larger than 95%.As a typical example,focusing on the stable type,we firstly predicted each component of aerodynamic drag applied on the crickets and analysed the drag contributions to the initial kinetic energy *** investigation revealed the mechanisms of the efficiently moving strategy against air resistance for the *** results show that the crickets can spin their hind legs to adjust body posture,thereby changing(increasing or decreasing)the air drag acting on the body to raise the efficiency during aerial *** work may advance the understanding of the significance of hind legs to insects’evolution and provide inspiration for future robot or micro aerial vehicle designs.

关键词： aerial movement air resistance robot designs energy dissipation

High-brightness near-infrared luminescent bioprobes based on lanthanide-doped Na3CrF6 nanoparticles

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Science China Materials 2024年第12期67卷 4113-4114页

作者： yun xing Shiqi Yu Datao Tu Xueyuan Chen State Key Laboratory of Structural Chemistry Fujian Key Laboratory of Nanomaterialsand CAS Key Laboratory of Design and Assembly of Functional NanostructuresFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Over the past decade,near-infrared(NIR)luminescent materials have emerged as a frontier in photonics and material science,finding diverse applications in bioimaging,encryption,and photodetection[1].Particularly,NIR nanoprobes are widely utilized in life science and clinical medicine because of their high spatial resolution,deep tissue penetration,low optical absorption and scattering,and minimal autofluorescence[2,3].

关键词： nanoparticles frontier utilized

Characterization of luminescent LTCC composite materials for white LED package

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Characterization of luminescent LTCC composite materials for...

Synthesis of Di-substituted Proazaphosphatrane and Its Application in Carbon-carbon Double-bond Isomerization

第八届中国功能材料及其应用学术会议

作者： LI xing-yun ZHOU Ji School of Materials Science& Engineering State Key Lab of New Ceramics & Fine ProcessingTsinghua University

ISBN: (纸本)9783037859698

Luminescent low temperature co-fired ceramic(LTCC) was prepared by sintering powders selected from BaO-TiO-BO-SiO system with limited amount of additive(Dy).It was found that the optimal sintering temperature was 900℃ based on the microstructure and the properties of sintering bodies,and then the major phases of the LTCC were Ba(TiO)SiO and *** experimental results indicated that the glass-ceramic possesses good yellow emission under 454 nm excitation,excellent dielectric properties:εr= 13.09,tanδ<0.001 at 1 ***,this material is supposed to be used as the LTCC substrate material for the application in white LED packaging.

关键词： white LED LTCC dielectric constant luminescent

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Chemical Research in Chinese Universities 2010年第5期26卷 768-772页

作者： WU Wei ZHANG Xiao-yun KANG Shou-xing Department of Chemistry China University of Petroleum（East China） Qingdao 266555 P. R. China

Diisopropyltren was synthesized from the reaction of tren with benzaldehyde in toluene, followed by reducing the imine intermediate with NaBH4, and debenzylation catalyzed by 10% Pd/C in methanol. It was then converted to its corresponding azaphosphatrane via ring-closing reaction of HMPT and triflic acid. Deprotonation of azaphosphatrane with potassium t-butoxide afforded the target diisopropyl proazaphosphatrane ld. A comparative study of compound ld for isomerization of allylic system and methylene-interrupted diene system revealed that compound ld is more efficient than its tri-substituted analoque（lb）. In acetonitrile at 40 ℃, allylaromatics were selectively isomerized to 1-arylpropene generally in an isolated yield more than 95% with trans, cis molar ratios in a range of 87/13 to 96/4. Allyl phenylsulfide was converted to 1-phenylthiopropene（molar ratio of Z/E=54/46） in a yield of 93%-95%. Methylene-interrupted dienes were also isomerized in high yield.

关键词： Proazaphosphatrane Isomerization Nonionic strong base

Does the Entrepreneurship of the Parents Affect the Opportunities of their Offspring＇s Entrepreneurship？ Empirical Analysis Based on the CGSS 2010-2013 Data

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2018年第2期13卷 196-222页

作者： Yongmei Hu yun xing Faculty of Education Beijing Normal University Beijing 100875 China College of Education Northwest Normal University Lanzhou 730070 China

The whole society is paying close attention to ＂entrepreneurship,＂ which urges researchers to find an explanatory perspective relatively independent and with causality on the intergenerational transfer of entrepreneurship. Based on the data of the Chinese General Social Survey （short for CGSS） during the years 2010-2013, this paper analyzes how parents＇ entrepreneurship affects the probability of their offspring＇s entrepreneurship, and the results show that compared with the offspring of parents who did not start their own business, those whose parents did are more likely to choose to start their own business. In view of historical facts such as the ＂lay-off wave＂ during China＇s transformation into a market economy, we use ＂the annual number of unemployed back to work,＂ a provincial-level indicator, in the 1990s as an instrumental variable to correct possible endogenous problems. We find that parents＇ entrepreneurship has significant positive effects on the probability of their offspring＇s entrepreneurship, which may result from the informal transfer of human capital and wealth from parents to their offspring.

关键词： entrepreneurial opportunities instrumental variable regression lay-offs intergenerational transfer

Generation of elliptical isolated attosecond pulse from oriented H_(2)^(+)in a linearly polarized laser field

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Chinese Physics B 2022年第4期31卷 281-286页

作者： yun-He xing Jun Zhang Xiao-Xin Huo Qing-yun Xu Xue-Shen Liu Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

We investigate the ellipticity of the high-order harmonic generation from the oriented H_(2)^(+)exposed to a linearly polarized laser field by numerically solving the two-dimensional time-dependent Schrodinger equation(2 D TDSE).Numerical simulations show that the harmonic ellipticity is remarkably sensitive to the alignment *** harmonic spectrum is highly elliptically polarized at a specific alignment angleθ=30°,which is insensitive to the variation of the laser *** position of the harmonic intensity minima indicates the high ellipticity,which can be attributed to the two-center interference *** high ellipticity can be explained by the phase difference of the *** result facilitates the synthesis of a highly elliptical isolated attosecond pulse with duration down to 65 as,which can be served as a powerful tool to explore the ultrafast dynamics of molecules and study chiral light-matter interaction.

关键词： high harmonic generation linearly polarized laser fields elliptical isolated attosecond pulse alignment angle two-center interference effect

Analytical model for Rayleigh-Taylor instability in conical target conduction region

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Chinese Physics B 2022年第10期31卷 450-457页

作者： Zhong-Yuan Zhu yun-xing Liu Ying-Jun Li Jie Zhang School of Science China University of Mining and TechnologyBeijing 100083China Double-cone Ignition(DCI)Joint Team State Key Laboratory for Geomechanics and Deep Underground EngineeringChina University of Mining and TechnologyBeijing 100083China Double-cone Ignition(DCI)Joint Team Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China

This work builds an isobaric steady-state fluid analytical-physical model of the plasma conduction region in a conical target. The hydrodynamic instability in the double-cone ignition scheme^([21]) for inertial confinement fusion(ICF) proposed by Zhang is studied with the built model. With this idealized model, the relevant parameters, such as density, temperature,and length of the plasma in the conduction region of the conical target under long-pulse conditions are given. The solution of the proposed analytical model dovetails with the trend of the numerical simulation. The model and results in this paper are beneficial for discussing how to attenuate Rayleigh-Taylor instability in ICF processes with conical and spherical targets.

关键词： double-cone ignition Rayleigh-Taylor instability conical target conduction region

Solidification Properties of CaO-SiO_2-TiO_2 Based Mold Fluxes

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Journal of Iron and Steel Research International 2011年第7期18卷 15-19,52页

作者： HE Sheng-ping HUANG Qing-yun ZHANG Guo-xing LU Yong-jian WANG Qian Chongqing Key Laboratory of Metallurgical Engineering College of Materials Science and EngineeringChongqing University Chongqing 400044 China

In continuous casting of peritectic steel grades sensitive to longitudinal cracking, the solidification properties of mold fluxes play an important role in keeping smooth running of continuous casting process and achieving high surface quality of casting strands. To reduce fluorine pollution in molten slag, types of CaO-SiO2-TiO2 （CTS） based mold fluxes were investigated. The solidification and crystallization properties, including viscosity η at 1 573 K, break temperature Tbr, crystallization ratio Rc and solidification mineragraphy were measured, which were compared with those of CaO-SiO2-CaF2 based mold fluxes. The experiments show that there are unstable viscosity-high tem- perature properties and high Tbr in part of CTS slag system, which are bad for lubrication between liquid flux film and strand. And when temperature is below Tbr, the viscosities change slowly during cooling in some part of this slag system, which imply that liquid mold fluxes solidify slowly and it is easy to cause surface longitudinal cracks on strand. Major mineragraphy of the CaO-SiO2-TiO2 based mold fluxes are CaO · TiO2 or CaO · TiO2 and CaO · SiO2 · TiO2. TiN and Ti（C,N） can be formed in mold fluxes bearing high TiO2 during the continuous casting.

关键词： mold flux solidification property peritectic steel mineragraphy

BMPR-IB gene disruption causes severe limb deformities in pigs

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Zoological Research 2022年第3期43卷 391-403页

作者： Qiang Yang Chuan-Min Qiao Wei-Wei Liu Hao-yun Jiang Qi-Qi Jing Ya-Ya Liao Jun Ren Yu-yun xing State Key Laboratory of Pig Genetic Improvement and Production Technology Jiangxi Agricultural UniversityNanchangJiangxi 330045China

In an attempt to generate g.A746G substitution in the BMPR-IB gene,we unexpectedly obtained BMPR-IB homozygous knockout piglets(BMPR-IB^(-/-))and heterogeneous knockout piglets with one copy of the A746G mutation(BMPR-IB-/746G)via CRISPR/Cas9 *** chain reaction(PCR)and sequencing revealed complex genomic rearrangements in the target *** BMPR-IBdisrupted piglets showed an inability to stand and walk *** BMPR-IB^(-/-)and BMPR-IB-/746G piglets exhibited severe skeletal dysplasia characterized by distorted and truncated forearms(ulna,radius)and disordered carpal,metacarpal,and phalangeal bones in the *** piglets displayed more severe deformities in the hindlimbs by visual inspection,including fibular hemimelia,enlarged tarsal bone,and disordered toe joint *** deformities were more profound in BMPR-IB^(-/-)piglets than in the BMPR-IB-/746G *** analysis identified 139 differentially expressed proteins(DEPs)in the hindlimb fibula of BMPR-IB-/746G piglets compared to the wild-type(WT)*** DEPs are involved in skeletal or embryonic development and/or the TGF-βpathway and tumor *** Ontology(GO)and protein domain enrichment analysis suggested alterations in these *** the top 50 DEPs,a large proportion,e.g.,C1QA,MYO1H,SRSF1,P3H1,GJA1,TCOF1,RBM10,SPP2,MMP13,and PHAX,were significantly associated with skeletal *** study provides novel findings on the role of BMPR-IB in mammalian limb development.

关键词： BMPR-IB A746G Pigs Limb deformities