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Synthesis of Novel Chiral 7-Amide Substituted-4-androstene-3,17-dione Derivatives

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Chemical Research in Chinese Universities 2011年第4期27卷 604-609页

作者： CHEN Shao-rui ZHOU xue-qin LI Wei LIU Dong-zhi School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China College of Science Hebei University of Science and Technology Shijiazhuang 050018 P. R. China

A series of novel 7-amide substituted-4-androstene-3,17-dione derivatives（8αa ＂8αh or 8βa ＂8βh） was synthesized from the important intermediates 5 by N-acylation and acidic *** 5α and 5β were obtained through the reaction sequence including acetalization,allylic oxidation,oximation and *** structures of the target compounds were characterized by MS,1H NMR,13C NMR and HRMS spectra and their stereo configurations were identified through DEPT（distortionless enhancement by polarization transfer）,HMQC（hetero-nuclear multiple quantum coherence） and NOE（nuclear overhauser effect） correlation.

关键词： Androstenedione Allylic oxidation Reduction N-Acylation

IK-CPA security implies IE-CCA security in the random oracle model

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Science China(Information Sciences) 2013年第3期56卷 179-189页

作者： xue rui State Key Laboratory of Information Security Institute of SoftwareChinese Academy of Sciences

Key-privacy is a notion of security that is concerned with the key anonymity in public-key *** popular schemes keep key-privacy,while others do ***-privacy has been shown to be orthogonal to data-privacy within one *** paper investigates the relationship between keyprivacy and data-privacy in public-key *** show that the existence of IK-CPA secure cryptosystems implies the existence of IE-CCA secure cryptosystems in the random oracle *** main contributions include a novel construction of a family of injective one-way trapdoor functions directly based on any IK-CPA secure public-key cryptosystem in the random oracle *** construction adopts a novel idea in the construction compared to the existing *** latter was based on unapproximable trapdoor *** novelty of the construction allows to show that the injective trapdoor functions are secure under correlated products with respect to uniform repetitional *** further allows us to conclude,in the random oracle model,that the existence of IK-CPA secure public-key cryptosystems implies the existence of CCA secure cryptosystems by a result of Rosen and Segev.

关键词： injective trapdoor functions IK-CPA security random oracle model IE-CCA security

Abiotic Stresses and Phytohormones Regulate Expression of FAD2 Gene in Arabidopsis thaliana

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Journal of Integrative Agriculture 2012年第1期11卷 62-72页

作者： YUAN Si-wei WU xue-long LIU zhi-hong LUO Hong-bing HUANG rui-zhi Key Laboratory of Plant Metabolic Engineering of Zhejiang Province/Institute of Virology and Biotechnology Zhejiang Academy of Agricultural Sciences Hangzhou 310021 P.R.China College of Agronomy Hunan Agricultural University Changsha 410128 P.R. China

Modification of unsaturated fatty acid （FA） levels has been found to accompany multiple abiotic stress acclimations in many plants. Delta 12 fatty acid desaturase （FAD2） plays a critical role in the synthesis of polyunsaturated FAs in plant cells by converting oleic acid （18：1） to linoleic acid （18：2）. To better understand the relationship between polyunsaturated FAs metabolism and stress adaptation, the expression of FAD2 gene and changes in the FA compositions under various abiotic stresses and phytohormone treatments in Arabidopsis thaliana was investigated in this study. A 1 423-bp promoter of the FAD2 gene was cloned and characterized from Arabidopsis. Several putative hormone- and stress- inducible cis-elements were identified in the cloned promoter, which include salt- and pathogen-inducible GT-1 motifs, low-temperature-responsive MYC element, dehydration-responsive MYB element, and GA signaling related WRKY71OS element. To investigate the fine regulation of FAD2 gene, a recombinant FAD2 promoter-GUS construct was introduced into Arabidopsis plants. Histochemical study showed that the promoter was ubiquitously active and responsive not only to exogenous phytohormones including ABA, 24-eBL, and SA but also to darkness, temperature, salt, and sucrose stresses in Arabidopsis seedlings. Consistent with the expression change, treatments with exogenous 24-eBL, ABA, SA, and NaCl resulted in reduction in polyunsaturated FAs in Arabidopsis seedlings. These findings suggest that the FAD2 gene with a wide variety of putative response elements in its promoter is responsive to multiple phytohormones and abiotic stresses and therefore may play an important role in stress responses of Arabidopsis during plant growth and seed development.

关键词： FAD2 abiotic stresses phytohormones fatty acid (FA) Arabidopsis thaliana

An explanation about the flat radio spectrum for Mrk 421

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Research in Astronomy and Astrophysics 2021年第4期21卷 311-318页

作者： rui xue Ze-rui Wang Department of Physics Zhejiang Normal UniversityJinhua 321004China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China

It is well known that a flat radio spectrum is a common property in the spectral energy distribution of *** one-zone leptonic models are generally successful in explaining the multi-wave band emission,they are problematic in reproducing the radio *** the study of Mrk 421,one-zone models suggest that in order to avoid overproducing the radio flux,the minimum electron Lorentz factor should be larger than a few hundred at least,even considering the synchrotron self-absorption *** result suggests that the model predicted spectral index in the radio band of Mrk 421 should be-1/*** the basis of this result,by assuming there is a neglected region that will also contribute the radio emission and its electron energy index naturally originates from the simplest first-order Fermi acceleration mechanism,we can get a superimposed flat radio *** this paper,a two-zone model is proposed to reproduce the quiescent state spectral energy distribution of Mrk *** addition to taking into account the emission from a conventional radiation zone,we further consider emission from the acceleration zone in which particles are accelerated at a shock *** the present model,our fitting result suggests that the low frequency flat radio spectrum of Mrk 421 might be explained as a superposition of the synchrotron emission from acceleration zone and radiation zone.

关键词： galaxies:active galaxies:jets radiation mechanisms:non-thermal

Hadronuclear interpretation of the possible neutrino emission from PKS B1424-418,GB6 J1040+0617 and PKS 1502+106

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Research in Astronomy and Astrophysics 2021年第12期21卷 375-382页

作者： Ze-rui Wang rui xue College of Physics and Electronic Engineering Qilu Normal UniversityJinhua 321004China Department of Physics Zhejiang Normal UniversityJinan 250200China

In addition to neutrino event IceCube-170922 A which is observed to be associated with aγ-ray flare from blazar TXS 0506+056,there are also several neutrino events that may be associated with *** them,PKS B1424-418,GB6 J1040+0617 and PKS 1502+106 are low synchrotron peaked sources,which are usually believed to have the broad line region in the vicinity of the central black *** are considered as counterparts of IceCube event 35,IceCube-141209 A and IceCube-190730 A,*** considering the proton-proton(pp)interactions between the dense gas clouds in the broad line region and the relativistic protons in the jet,we show that the pp model that is applied in this work can not only reproduce the multi-waveband spectral energy distribution but also suggest a considerable annual neutrino detection *** also discuss the emission from the photopion production and Bethe-Heitler pair production with a sub-Eddington jet power that is suggested in our model and find that it has little effect on the spectrum of total emission for all of three sources.

关键词： neutrinos galaxies:active galaxies:jets radiation mechanisms:non-thermal

Hot Compression Behavior of Mg-Gd-Y-Zn-Zr Alloy Containing LPSO with Different Morphologies

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Acta Metallurgica Sinica(English Letters) 2023年第10期36卷 1680-1698页

作者： rui Guo Xi Zhao Bo-Wen Hu xue-Dong Tian Qiang Wang zhi-Min Zhang School of Material Science and Engineering North University of ChinaTaiyuan030051China School of Aeronautics and Astronautics North University of ChinaTaiyuan030051China

In this study,hot compression behavior of as-homogenized Mg-9Gd-4Y-2Zn-0.5Zr alloys containing long period ordered(LPSO)phases with different initial morphologies was investigated under a strain rate of 0.01 s−1 at 450°*** microstructure,texture evolution and dynamic recrystallization(DRX)mechanism under different strains(0.1,0.3,0.5,0.7,and 1.4)were *** compression conditions,the block-shape phase and deformedα-Mg matrix were regularly arranged vertically in the compression direction(CD).The particle phase(Mg5RE)and amount of kink bands were *** degree of kink increased initially and decreased significantly when the deformation strain reached *** DRX mechanisms were produced during the compression process:(i)The block LPSO,Mg5RE and Zr-Zn phase activated DRX through the particle stimulated nucleation(PSN)mechanism.(ii)Several DRX activated on the serrated grain boundary between the two parent grains through discontinuous DRX(DDRX)mechanism.(iii)A large number of kink bands and larger spacing of lamellar LPSO increased the nucleation of DRX through continuous DRX(CDRX)*** combination of different recrystallization mechanisms has evident effects on grain *** increased as compression proceeds,and the texture was gradually weakened.

关键词： Mg-Gd-Y-Zn-Zr alloy Compression Long period ordered(LPSO)phase Recrystallization mechanism

Synthesis of Highly Branched Poly(ε-caprolactone) by Self-condensing Atom Transfer Radical Polymerization of Macroinimers

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Chinese Chemical Letters 2006年第3期17卷 373-376页

作者： rui xue LIU Yan SHI zhi Feng FU Shu Ke JIAO Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Technology Beijing 100029

Branched poly（ε-capmlactone） was synthesized by self-condensing atom transfer radical polymerization of macroinimer, α-acryloyoxy-ω-2-bromopropionyloxy poly（ε-caprolactone）, which was prepared by enzyme-catalyzed ring-opening polymerization of ε-caprolactone with 2-hydroxylethyl acrylate as initiator and esterification of the ω-hydroxyl group of the obtained poly（ε-caprolactone） by 2-bromopropionyl bromide.

关键词： Self-condensing vinyl polymerization atom transfer radical polymerization branched polymers poly(ε-caprolactone).

A novel LAAS pseudo-range error over-bound method based on improved pseudo-range error distribution model

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Chinese Journal of Aeronautics 2013年第3期26卷 638-645页

作者： xue rui Wang Zulin School of Electronics and Information Engineering Beihang University

The high level of safety demand of civil aviation requests local area augmentation system （LAAS） extremely high navigation integrity performance. A new LAAS pseudo-range error overbound method is proposed in this paper to improve the integrity of LAAS. Firstly, a more practical pseudo-range error distribution model is established. Then, by calculating the relationship between the statistical uncertainty of the model parameter and the integrity risk, a new method is proposed to calculate the pseudo-range error over-bound model. This method can effectively reduce the inflation factor and the resulting conservativeness of the over-bound model. Comparative experiments show that the method proposed in this paper performs better and satisfies the requirements of real applications.

关键词： Augmentation system Error statistics Probability density function Parameter estimation Satellite navigation Signal analysis Uncertainty analysis

A brief review on Majorana bound states in topological superconductors

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Science China(Physics,Mechanics & Astronomy) 2016年第7期59卷 1-8页

作者： rui Lin zhi Wang School of Physics and Engineering Sun Yat-sen University

Topological superconductivity has drawn much attention recently, and most interests are focused on the Majorana bound states existing at the edges of one-dimensional topological superconductors. These Majorana bound states are ideal platform for studying non-Abelian statistics. Meanwhile, they are proposed to be useful in quantum computation. In this review, we introduce the basic concepts and models in this area. We begin from the Kitaev model, which is the most concise model for one-dimensional topological superconductivity. Then, we discuss how to realize this model with spin-orbit coupling in realistic materials. Finally, we show some simple methods to detect the Majorana bound states and study their novel properties with the help of adjacent quantum dots.

关键词： topological superconductor Kitaev model quantum dot