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Journal of Materials Science & Technology 2004年第1期20卷 78-80页

作者： fengwang YuanshengJIN DunyuanHU JishanZHANG StateKeyLaboratoryofTribology TsinghuaUniversityBeijing100084China StateKeyLaboratoryforAdvancedMetalsandMaterials UniversityofScienceandTechnologyBeijingBeijing100083China

Spray deposition is a novel process which is used to manufacture rapidly solidified bulk and near-net-shape preforms. In this study, AI-20Si-5Fe-3Mn-3Cu-1Mg alloy was synthesized by spray deposition technique. The aging process of the alloy was investigated by differential scanning calorimetry (DSC) analysis and transmission electron microscopy (TEM). The results show that two kinds of phases, i.e. S(Al2CuMg) and σ(Al5Cu6Mg2), precipitate from matrix and improve the tensile strength of the alloy efficiently at both the ambient and elevated temperatures (300℃). In addition, the σ-Al5Cu6Mg2 is a relatively stable phase which improves microstructural stability of the alloy.

关键词： Spray deposition Precipitate Tensile strength Microstructural stability

Circulating microRNAs in cardiovascular diseases： from biomarkers to therapeutic targets

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Frontiers of Medicine 2014年第4期8卷 404-418页

作者： fengwang Chen Chen Daowen Wang Department of Internal Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

microRNAs （miRNAs） are a class of conserved, short, non-coding RNAs that have important and potent capacities to regulate gene expression at the posttranscriptional level. In the past several years, the aberrant expressions of miRNAs in the cardiovascular system have been widely reported, and the crucial roles of some special miRNAs in heart development and pathophysiology of various cardiovascular diseases have been gradually recognized. Recently, it was discovered that miRNAs are presented in peripheral circulation abundantly and stably. This has raised the possibility of using circulating miRNAs as biomarkers for diseases. Furthermore, some studies demonstrated that circulating miRNAs may serve as novel extracellular communicators of cell-ceU communication. These discoveries not only reveal the functions of circulating miRNAs in cardiovascular system but also inform the development of miRNAs therapeutic strategies. In this review, we discuss the potential roles of circulating miRNAs in a variety of cardiovascular diseases from biomarkers to therapeutic targets to clearly understand the roles of circulating miRNAs in cardiovascular system.

关键词： microRNA cardiovascular disease biomarkers therapeutic target

Starch Mobilization in Ultradried Seed of Maize （Zea mays L.） During Germination

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Journal of Integrative Plant Biology 2005年第4期47卷 443-451页

作者： Xiao-fengwang Xin-MingJING JianLIN CollegeofBiology BeijingForestryUniversityBeijing100083China／／InstituteofBotanytheChineseAcademyofSciencesBeijing100093China InstituteofBotany theChineseAcademyofSciencesBeijing100093China

: The effects of ultradry storage on the starch mobilization in maize (Zea mays L.) seed after aging were investigated. The results indicated that there were no significant differences in the content of ATP, starch, and soluble sugar, as well as the activity of amylase, between ultradried seeds and seeds stored at ?20 °C during germination. These results were consistent with the higher level of vigor of the ultradried seed. Sieve tube introduction of a fluorescence dye (carboxyl fluoresceindiacetate) and laser confocal microscopy were used to study the development of plasmodesmata in the ultradried seeds. The results indicated that plasmodesmata developed well in ultradried seeds. Fluorescence analysis also showed that the fluorescence intensity in the radicle of ultradried seeds was stronger than that in seeds with a higher moisture content. This suggests that ultradry treatment has no adverse effects on the seeds. After seed imbibition, cell orgaelles could be resumed. It is concluded that ultradry seed storage is beneficial for maintaining seed vigor and that starchy mobilization proceeds regularly during germination.

关键词： ATP germination maize (Zea mays L.) plasmodesmata starch mobilization ultradry seed storage

The Peak Luminosity of Type Ia Supernovae and its Implications for the Cosmic Expansion Rate

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Chinese Journal of Astronomy and Astrophysics 2001年第3期1卷 257-270页

作者： Xiao－fengwang Zong－WeiLi 等 DepartmentofAstronomy BeijingNormalUniversityBeijing100875 DepartmentofAstronomy BeijingNormalUniver

Supernovae of type Ia (SNe Ia) are confirmed to be the best distance indicators to derive the cosmic expansion rate. The dispersion of their peak luminosity at optical bands (BVI) is approximate to 0.13 mag, after taking into account the effects of the second parameters (i.e., the Antial decline rate m15(B) and (B - V) color at maximum light). The local calibrations from HST indicate an absolute magnitude of 19.48 ± 0.08mag (in V band) for SNe Ia in spiral galaxies. The current expansion rate, Ho, is found to be 63.6 ± 1.8 (random) ±5.7 (systematic) kms-1 Mpc-1. This Value will decrease by 3% when the metallicity effect on the cepheid distances is considered. In addition, a marginal local outward flow of 4.0 ± 4.5% within the velocity-distance of 7000 km s-1 can be inferred from SNe Ia for the Einstein-de Sitter universe; however, this outward flow is only 2.2 ± 4.4% for an accelerating expansion universe (which is supported by high-z SNe Ia).

关键词： Cosmology: observations - distance scale - supernovae: general

Overexpression of auxin/indole-3-acetic acid gene MdIAA24 enhances Glomerella leaf spot resistance in apple(Malus domestica)

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Horticultural Plant Journal 2024年第1期10卷 15-24页

作者： Qian Wang Dong Huang Wenyan Tu fengwang Ma Changhai Liu State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China

Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains *** this study,we investigated the function of auxin/indole-3-acetic acid(IAA)gene Md IAA24 overexpression in enhancing apple resistance to Glomerella leaf spot(GLS)caused by Colletotrichum fructicola(Cf).Analysis revealed that,upon Cf infection,35S::Md IAA24 plants exhibited enhanced superoxide dismutase(SOD)and peroxidase(POD)activity,as well as a greater amount of glutathione(reduced form)and ascorbic acid accumulation,resulting in less H_(2)O_(2)and superoxide anion(O_(2)^(-))in apple ***,35S::Md IAA24 plants produced more protocatechuic acid,proanthocyanidins B1,proanthocyanidins B2 and chlorogenic acid when infected with *** Cf infection,35S::Md IAA24 plants presented lower levels of IAA and jasmonic acid(JA),but higher levels of salicylic acid(SA),along with the expression of related *** overexpression of Md IAA24 was observed to enhance the activity of chitinase andβ-1,3-glucanase in Cfinfected *** results indicated the ability of Md IAA24 to regulate the crosstalk between IAA,JA and SA,and to improve reactive oxygen species(ROS)scavenging and defense-related enzymes *** jointly contributed to GLS resistance in apple.

关键词： Apple MdIAA24 Glomerella leaf spot(GLS) Antioxidant capacity Auxin Salicylic acid Jasmonic acid

Mono- and Binuclear Cobalt(Ⅱ) Complexes Supported by Quinoline-2- imidate Ligands： Synthesis, Characterization, and 1,3-Butadiene Polymerization

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Chinese Journal of Polymer Science 2018年第8期36卷 943-952页

作者： Heng Liu Rui Zhuang Bo Dong fengwang Yan-Ming Hu Xue-Quan Zhang CAS Key Laboratory of Synthetic Rubber Changchun lnstitute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100049 China College of Materials Science and Engineering Jilin University Changchun 130022 China

A series of mono-and binuclear Co（Ⅱ） complexes （Col-Co7） supported by quinoline-2-imidate ligands were synthesized and thoroughly characterized. Measured by single crystal X-ray crystallography, complexes Col and Co3 adopted distorted tetrahedral structures around the cobalt center. Upon activation by ethylaluminium sesquichloride （EASC）, these cobalt complexes exhibited high catalytic activity and cis-l,4-selectivity towards 1,3-butadiene polymerization. The effects of ligand environment, polymerization temperature, and cocatalyst types on the polymerization were investigated in detail. Interestingly, the binuclear Co（Ⅱ） complexes exhibited high thermal stability, and the polymer yields were up to 97.2% even at a high temperature of 70 ℃.

关键词： Late transition metal Cobalt(Ⅱ) complexes Coordination polymerization Polybutadiene

Effects of location within the tree canopy on carbohydrates,organic acids,amino acids and phenolic compounds in the fruit peel and flesh from three apple(Malus×domestica)cultivars

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Horticulture Research 2014年第1期1卷 214-220页

作者： Fengjuan Feng Mingjun Li fengwang Ma Lailiang Cheng Department of Horticulture Cornell UniversityIthacaNY 14853USA School of Management Shandong Jiaotong UniversityJinan 250357China State Key Laboratory of Crop Stress Biology for Arid Areas College of HorticultureNorthwest A&F UniversityYangling 712100China

Fruits from three cultivars of apple(Malus × domestica Borkh.)—‘McIntosh’,‘Gala’and‘Mutsu’—were harvested from the exterior and interior of the tree *** and flesh tissues were sampled separately to determine how the position of the fruit on the tree might affect the levels of the primary and secondary metabolites in the *** from the outer-canopy had a higher fresh weight and a higher soluble solids content compared with inner-canopy *** the flesh and peel of the outer-canopy fruit had higher concentrations of soluble sugars and sugar alcohols,but lower starch concentrations than the inner-canopy *** position did not significantly affect malic acid concentrations,except in the peel of‘McIntosh’and the flesh of‘Mutsu’.Although levels of ascorbic and succinic acids were higher in the peel of the outer-canopy fruit,the responses of other organic acids to canopy position depended on tissue type and *** for histidine,lysine,threonine and glycine,most amino acids accumulated at higher concentrations in the inner-canopy *** contrast,levels of phenolic compounds from both the peel and flesh were significantly higher in the outer-canopy *** significant effects of location within the canopy on both primary metabolites and secondary metabolites demonstrate the importance of light exposure on apple fruit quality.

关键词： phenolic outer sugar

Cluster synchronization in complex network of coupled chaotic circuits： An experimental study

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Frontiers of physics 2018年第5期13卷 183-193页

作者： Ben Cao Ya-fengwang Liang Wang Yi-Zhen Yu Xin-Gang Wang School of Physics and Information Technology Shaanxi Normal University Xi'an 710062 China School of Physical Education Shaanxi Normal University Xi'an 710062 China

By a small-size complex network of coupled chaotic Hindmarsh-Rose circuits, we study experimen- tally the stability of network synchronization to the removal of shortcut links. It is shown that the removal of a single shortcut link may destroy either completely or partially the network synchroniza- tion. Interestingly, when the network is partially desynchronized, it is found that the oscillators can be organized into different groups, with oscillators within each group being highly synchronized but are not for oscillators from different groups, showing the intriguing phenomenon of cluster synchro- nization. The experimental results are analyzed by the method of eigenvalue analysis, which implies that the formation of cluster synchronization is crucially dependent on the network symmetries. Our study demonstrates the observability of cluster synchronization in realistic systems, and indicates the feasibility of controlling network synchronization by adjusting network topology.

关键词： chaos synchronization pattern formation neuronal circuits

Tunable metallic-like transport in polypyrrole

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Materials Futures 2022年第1期1卷 3-8页

作者： Xiaoling Zang Yuqian Jiang Yuqiao Chai fengwang Li Junhui Ji Mianqi Xue Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijingPeople’s Republic of China Laboratory for Nanosystem and Hierarchy Fabrication National Center for Nanoscience and TechnologyBeijingPeople’s Republic of China School of Chemical and Biomolecular Engineering and The University of Sydney Nano Institute The University of SydneySydneyNew South WalesAustralia College of Chemistry and Materials Engineering Beijing Technology and Business UniversityBeijingPeople’s Republic of China Beijing National Laboratory for Molecular Sciences BeijingPeople’s Republic of China

Conjugated polymers(CPs),organic macromolecules with a linear backbone of alternating C–C and C=C bonds,possess unique semiconductive properties,providing new opportunities for organic electronics,photonics,information,and energy *** the metallic or metallic-like,even superconducting properties beyond semiconductivity in CPs is always one of the ultimate goals in polymer science and condensed *** two metallic and semi-metallic transport cases—aniline-derived polyaniline and thiophene-derived poly(3,4-ethylenedioxythiophene)—have been reported since the development of CPs for four *** synthesis is a key challenge in discovering more *** we report the metallic-like transport behavior of another CP,polypyrrole(PPy).We observe that the transport behavior of PPy changes from semiconductor to insulator-metal transition,and gradually realizes metallic-like performance when the crystalline degree *** a generalized Einstein relation model,we rationalized the mechanism behind the *** metallic-like transport in PPy demonstrates electron strong correlation and phonon–electron interaction in soft condensation matter,and may find practical applications of CPs in electrics and spintronics.

关键词： conjugated polymers metallic-like polypyrrole transport behavior

Ultra-small Cu nanoparticles embedded in N-doped carbon arrays for electrocatalytic CO2 reduction reaction in dimethylformamide

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Nano Research 2018年第7期11卷 3678-3690页

作者： Xiaolong Zhang Ying Zhang fengwang Li Christopher D. Easton Alan M. Bond Jie Zhang School of Chemistry Monash University Clayton 3800 VIC Australia ARC Centre of Excellence for Electromaterials Science Monash University Clayton 3800 VIC Australia CSIRO Manufacturing BayviewAvenue Clayton 3168 VIC Australia

The development of heterogeneous catalysts with a well-defined micro structure to promote their activity and stability for electrocatalyfic CO2 reduction has been shown to be a promising strategy. In this work, Cu nanoparticles （- 4 nm in diameter） embedded in N-doped carbon （Cu@NC） arrays were fabricated by thermal decomposition of copper tetracyanoquinodimethane （CuTCNQ） under N2. Compared to polycrystalline copper electrodes, the Cu@NC arrays provide a significantly improved number of catalytically active sites. This resulted in a 0.7 V positive shift in onset potential, producing a catalytic current density an order magnitude larger at a potential of -2.7 V vs. Fc/Fc＋（Fc = ferrocene） in dimethylformamide （DMF）. By controlling the water content in the DMF solvent, the CO2 reduction product distribution can be tuned. Under optimal conditions （0.5 vol.% water）, 64% HCOO^-, 20% CO, and 13% H2 were obtained. The Cu@NC arrays exhibited excellent catalytic stability with only a 0.5% decrease in the steady-state catalytic current during 6 h of electrolysis. The three-dimensional （3D） array structure of the Cu@NC was demonstrated to be effective for improving the catalytic activity of copper based catalysts while maintaining long-term catalytic stability.

关键词： copper tetracyanoquinodimethane (CuTCNQ) copper carbon arrays CO2 reduction electrocatalysis