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Effects of Input Spectra on the Threshold of Modulation Instability in a Single-Mode Fiber

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Chinese Physics Letters 2012年第4期29卷 116-118页

作者： CHEN Wei meng Zhou ZHOU Hui-juan LUO Hong Department of Optic Information Science and Technology College of Optoelectronic Science and EngineeringNational University of Defense TechnologyChangsha 410073

We investigate modulation instability (MI) in the presence of a monochromatic spectrum and on the background of a broadband amplified spontaneous emission spectrum induced by an erbium-doped fiber amplifier,*** the former case,the MI threshold is ~110mW,which agrees well with the theoretical ***,for the latter case,the threshold is as high as ~170mW,which indicates that the MI threshold depends on the shape of the input spectrum and that the broadband spectrum has a higher threshold than the monochromatic one.

关键词： amplifier fiber spectrum

Transcriptional analysis of sex pheromone biosynthesis signal genes in Bombyx mori

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Insect Science 2012年第6期19卷 621-632页

作者： Shi-Heng An meng-Fang Du Li-juan Su Xin-Ming Yin College of Plant Protection Henan Agricultural UniversityZhengzhouChina College of Life Science Henan Agricultural UniversityZhengzhouChina

Six sex pheromone synthesis signal genes, including aeyl coenzyme A （acyl- CoA） desaturase （desatl）, fatty acyl reduetase （FAR）, pheromone biosynthesis activating neuropeptide receptor （PBANR）, fatty acid transport protein （FATP）, acyl-CoA binding protein （ACBP） and store-operated channel protein （OrailA）, were studied for their tran- scriptional regulations. The expression profiles of these transcripts at different develop- mental stages （from -96 to 48 h） revealed that the genes are expressed in an age-dependent manner. The transcripts of these genes continued to increase despite decapitation, and compared with normally developmental females, decapitation significantly inhibited their expression. Further experiments with a methoprene, a juvenile hormone （JH） analogue, challenge showed that JH was not a key inhibiting factor in the expression of these genes, and mating was found to significantly inhibit the expression of these marker genes. Alto- gether, the results provide a reference for understanding the mechanism of sex pheromone synthesis.

关键词： Bombyx mori sex pheromone biosynthesis signal genes transcriptionalregulation

Size matters:Steric hindrance of precursor molecules controlling the evolution of CdSe magic-size clusters and quantum dots

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Nano Research 2022年第9期15卷 8564-8572页

作者： juan Shen Chaoran Luan Nelson Rowell Yang Li meng Zhang Xiaoqin Chen Kui Yu Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Laboratory of Ethnopharmacology Tissue-orientated Property of Chinese Medicine Key Laboratory of Sichuan ProvinceWest China School of MedicineWest China HospitalSichuan UniversityChengdu 610065China Metrology Research Centre National Research Council CanadaOttawaOntario K1A 0R6Canada Engineering Research Center in Biomaterials Sichuan UniversityChengdu 610065China

Little is known about how to precisely promote the selective production of either colloidal semiconductor metal chalcogenide(ME),magic-size clusters(MSCs),or quantum dots(QDs).Recently,a two-pathway model has been proposed to comprehend their evolution;here,we reveal for the first time that the size of precursors plays a decisive role in the selected evolution pathway of MSCs and *** the reaction of cadmium myristate(Cd(MA)2)and tri-n-octylphosphine selenide(SeTOP)in 1-octadecene(ODE)as a model system,the size of Cd precursors was manipulated by the steric hindrance of carboxylic acid(RCOOH)*** RCOOH,the reaction produced both CdSe MSCs and QDs(from 100 to 240℃).With RCOOH,the reaction produced MSCs or QDs when R was small(such as CH3−)or large(such as C6H5−),*** to the twopathway model,the selective evolution is attributed to the promotion and suppression of the self-assembly of Cd and Se precursors,*** propose that the addition of carboxylic acid may occur ligand exchange with Cd(MA)2,causing the different sizes of Cd *** results suggest that the size of Cd precursors regulates the self-assemble behavior of the precursors,which dictates the directed evolution of either MSCs or *** present findings bring insights into the two-pathway model,as the size of M and E precursors determine the evolution pathways of MSCs or QDs,the understanding of which is of great fundamental significance toward mechanism-enabled design and predictive synthesis of functional nanomaterials.

关键词： cadmium selenide(CdSe) magic-size clusters(MSCs) quantum dots(QDs) self-assembly steric hindrance

LISR28 Is Involved in Pollen Germination by Affecting Filamentous Actin Dynamics

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Molecular Plant 2013年第4期6卷 1163-1175页

作者： Li-juan Cao meng-meng Zhao Chang Liu Huai-Jian Dong Wang-Cheng Li Hai-Yun Ren Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education College of Life Science Beijing Normal University Beijing 100875China

Alternative splicing plays important roles in gene regulation and contributes to protein complexity. Previous studies suggest that alternative splicing exists in members of the villin/gelsolin/fragmin superfamily. In this study, a ser- ine/argine-rich （SR） protein cDNA with 28kDa protein （LISR28） was isolated from a lily （Lilium Iongiflorum） expression library. Protein domain analysis showed that LISR28 had similar structures to Arabidopsis SR45 （AtSR45）, and LISR28 could complement the phenotype of loss of AtSR45 function. Therefore, overexpression of LISR28 and AtSR45 mutant （atsr45-1） were used in the following experiments. Overexpression of LISR28 in Arabidopsis completely inhibited pollen germina- tion. In contrast, the pollen germination of atsr45-1 was earlier than that of wild-type. In addition, pollen of atsr45-1 contained less F-actin at the corresponding hydration stage during pollen germination compared to that of wild-type. Alternative splicing analysis showed that Arabidopsis villinl （AtVLN1） transcript encoding the full-length protein was increased, and that encoding the truncated protein was decreased in atst45-1. Moreover, the mRNA expression level of other actin-binding proteins （ABPs） abundant in Arabidopsis pollen was also changed in atsr45-1. In conclusion, we hypothesize that LISR28 alters F-actin dynamics probably through its alternative splicing activities to affect directly or indirectly the alternative splicing of AtVLN1 and the expression of different ABPs, which then affects the pollen germination.

关键词： SR protein alternative splicing F-actin.

Tuning the reactivity of Al-Ni by fine coating of halogen-containing energetic composites

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Defence Technology（防务技术） 2022年第10期18卷 1810-1821页

作者： Su-lan Yang Ke-juan meng Wu-xi Xie Hong-qi Nie Qi-Long Yan Science and Technology on Combustion Internal Flow and Thermo-Structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China b Xi'an Modern Chemistry Research Institute Xi'an710065China

In this paper,various core-shell structured Al—Ni@ECs composites have been prepared by a spray-drying *** involved ECs refer to the energetic composites(ECs)of ammonium perchlorate/nitrocellulose(AP/NC,NA)and polyvinylidene fluoride/hexanitrohexaazaisowurtzitane(PVDF/CL-20,PC).Two Al—Ni mixtures were prepared at atomic ratios of 1:1 and 1:3 and named as Al/Ni and Al/3Ni,*** thermal reactivity and combustion behaviors of Al—Ni@ECs composites have been comprehensively *** showed that the reactivity and combustion performance of Al—Ni could be enhanced by introducing both NA and PC energetic *** which the Al/Ni@NA composite exhibited higher reactivity and improved combustion *** measured flame propagation rate(v=20.6 mm/s),average combustion wave temperature(T_(max)=1567.0°C)and maximum temperature rise rate(γ_(t)=1633.6°C/s)of Al/Ni@NA are higher than that of the Al/Ni(v=15.8 mm/s,T_(max)=858.0°C,andγ_(t)=143.5°C/s).The enhancement in combustion properties could be due to presence of the acidic gaseous products from ECs,which could etch the Al_(2)O_(3)shell on the surface of Al particles,and make the inner active Al to be easier transported,so that an intimate and faster intermetallic reaction between Al and Ni would be ***,the morphologies and chemical compositions of the condensed combustion products(CCPs)of Al—Ni@ECs composites were found to be different depending on the types of *** compositions of CCPs are dominated with the Al—Ni intermetallics,combining with a trace amount of Al_(5)O_(6)N and Al_(2)O_(3).

关键词： Arrested high energy ball milling Intermetallic alloy Combustion performance Energetic composites Reactivity control

A Bilinear Bcklund Transformation and N-Soliton-Like Solution of Three Coupled Higher-Order Nonlinear Schrdinger Equations with Symbolic Computation

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Communications in Theoretical Physics 2008年第9期50卷 689-695页

作者： ZHU Hong-Wu TIAN Bo meng Xiang-Hua LI juan XU Tao School of Science P.O. Box 122 Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China Hunan Meteorological Observatory Changsha 410007 China

A bilinear Baecklund transformation is presented for the three coupled higher-order nonlinear Schroedinger equations with the inclusion of the group velocity dispersion, third-order dispersion and Kerr-law nonlinearity, which can describe the dynamics of alpha helical proteins in living systems as well as the propagation of ultrashort pulses in wavelength-division multiplexed system. Starting from the Baecklund transformation, the analytical soliton solution is obtained from a trivial solution. Simultaneously, the N-soliton-like solution in double Wronskian form is constructed, and the corresponding proof is also given via the Wronskian technique. The results obtained from this paper might be valuable in studying the transfer of energy in biophysics and the transmission of light pulses in optical communication systems.

关键词： coupled higher-order nonlinear Schroedinger equations Baecklund transformation soliton solution Wronskian technique symbolic computation

Reaction mechanism of D + ND→N + D_2 and its state-to-state quantum dynamics

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Chinese Physics B 2019年第2期28卷 173-178页

作者： Ting Xu juan Zhao Xian-Long Wang Qing-Tian meng School of Physics and Electronics Shandong Normal University College of Science Shandong Jiaotong University

The quantum state-to-state calculations of the D + ND→N + D_2 reaction are performed on a potential energy surface of 4 A'' state. The state-resolved integral and differential cross sections and product state distributions are calculated and discussed. It is found that the rotational distribution, rather than the vibrational distribution, of the product has an obvious inversion. Due to the fact that it is a small-impact-parameter collision, its product D_2 is mainly dominated by rebound mechanism, which can lead to backward scattering at low collision energy. As the collision energy increases, the forward scattering and sideward scattering begin to appear. In addition, the backward collision is also found to happen at high collision energy, through which we can know that both the rebound mechanism and stripping mechanism exist at high collision energy.

关键词： state-to-state quantum dynamics time-dependent wave packet D+ND differential cross section

Synthesis of 5-vinyl-2-norbornene through Diels-Alder reaction of cyclopentadiene with 1,3-butadiene in supercritical carbon dioxide

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Chinese Chemical Letters 2017年第4期28卷 900-904页

作者： Fan-Qiang meng Xiu-juan Feng Wan-Hui Wang Ming Bao State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116023 China School of Petroleum and Chemical Engineering Dalian University of Technology Panjin 124221 China

An efficient method for the synthesis of 5-vinyl-2-norbornene from cyclopentadiene and 1,3-butadiene was *** Diels-Alder reaction of cyclopentadiene with 1,3-butadiene proceeded smoothly in supercritical carbon dioxide in the absence of any polymerization inhibitor to produce the corresponding5-vinyl-2-norbornene in satisfactory yield with high selectivity.

关键词： 5-Vinyl-2-norbornene Diels-Alder reaction Cyclopentadiene 1 3-Butadiene Supercritical carbon dioxide

Negative Differential Resistance and Rectifying Effects of Diblock Co-Oligomer Molecule Devices Sandwiched between C_2N-h2D Electrodes

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Chinese Physics Letters 2019年第4期36卷 75-78页

作者： meng Ye Cai-juan Xia Bo-Qun Zhang Yue Ma School of Science Xi'an Polytechnic University

Based on nonequilibrium Green's function method in combination with density functional theory, we study the electronic transport properties of dipyrimidinyl-diphenyl molecules embedded in a carbon atomic chain sandwiched between zigzag graphene nanoribbon and different edge geometries C_2N-h2D electrodes. Compared with the graphene electrodes, the C_2N-h2D electrode can cause rectifying and negative differential resistance *** C_2N-h2D with zigzag edges, a more remarkable negative differential resistance phenomenon appears, whereas armchair-edged C_2N-h2D can give rise to much better rectifying behavior. These results suggest that this system can be potentially useful for designs of logic and memory devices.

关键词： nonequilibrium system memory