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Charge-controlled compositional/microstructural regulations and electrochemical actuation performance of bulk nanoporous Ni-Pd alloys

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Rare Metals 2024年第10期43卷 5305-5317页

作者： Fu-Quan Tan Qing-Guo Bai Bin Yu jian-feng wang Zhong-Hua Zhang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and EngineeringShandong University School of Applied Physics and Materials Wuyi University Ira A.Fulton School of Engineering Arizona State University

Bulk nanoporous （np） metallic actuators have attracted increasing attention due to their large strain and low stimulation ***,studies focusing upon the combined effect of composition and structure on the actuation performance of metallic actuators are relatively scarce,and its underlying mechanism needs to be clarified Herein,a series of bulk np-NiPd samples with differen compositions and microstructures were fabricated using a dealloying-coarsening-dealloying strategy and chargecontrolled electrochemical dealloying,and the process involves only one component of precursor *** has been found that the np-NiPd cubes show a composition/structure-dependent mechanical property and electrochemical actuation ***,the npNi70Pd30sample with a homogeneously porous structure and good network connectivity exhibits significantly larger strain amplitude and faster strain rate than other hierarchically porous NiPd samples (np-Ni50Pd50and npNi20Pd80).Moreover,the np-Ni70Pd30sample demonstrates good actuation stability with high strain retention after hundreds of ***,the maximum strain amplitude （1.17%） is even comparable to that of advanced leadfree piezoceramic,and the maximum strain rate exceeds those of many reported metallic actuator *** work indicates that good network connectivity plays a vita role in facilitating large/fast strain response in metallic actuators.

关键词： Actuation stability Bulk nanoporous NiPd Electrochemical dealloying Good network connectivity Metallic actuators

Suppression of the regrowth interface leakage current in AlGaN/GaN HEMTs by Fe doped GaN substrate

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Science China(Information Sciences) 2024年第6期67卷 461-462页

作者： Xiao wang Zhi-Yu LIN Yuan-Hang SUN Long YUE Yu-Min ZHANG jian-feng wang Ke XU School of Nano-Tech and Nano-Bionics University of Science and Technology of China Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of Sciences Information Materials Research Department Suzhou laboratory Suzhou Nanowin Science and Technology Co. Ltd. jiangsu Institute of Advanced Semiconductors

In the process of homoepitaxy AlGaN/GaN heterojunction by metal-organic chemical vapor deposition (MOCVD) on free-standing substrates,Si impurities from the air and reaction chamber accumulate at the regrowth interfac...

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Inertia and Spectral Symmetry for the Eccentricity Matrices of Clique Trees

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Acta Mathematicae Applicatae Sinica 2024年

作者： Xiao-hong LI jian-feng wang Maurizio BRUNETTI School of Mathematics and Statistics Shandong University of Technology Basic Education Department Weifang Engineering Vocational College Department of Mathematics and Applications University Federico II'

The eccentricity matrix E(G) of a connected graph G is obtained from the distance matrix of G by leaving unchanged the largest nonzero entries in each row and each column,and replacing the remaining ones with *** this paper,we consider the set CT of clique trees whose blocks contain at most two cut-vertices of the clique *** with studying the structural properties of a clique tree in CT,we prove its eccentricity matrix to be irreducible,and then determine its inertia showing that every graph in CT with more than four vertices and odd diameter has two positive and two negative *** E-eigenvalues and negative E-eigenvalues turn out to be equal in number even for graphs in CT with even diameter;that shared cardinality also counts the‘diametrally distinguished’***,we prove that the spectrum of the eccentricity matrix of a clique tree G in CT is symmetric with respect to the origin if and only if G has an odd diameter and exactly two adjacent central *** results generalize those achieved on trees by *** and *** in 2022.

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Effect of morphological gene mutation and decay on energy dissipation behaviour of granular soils

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第4期24卷 303-318页

作者： Wei XIONG Qi-min ZHANG jian-feng wang Department of Architecture and Civil Engineering City University of Hong KongHong KongChina Shenzhen Research Institute of City University of Hong Kong Shenzhen 518057China

In this paper,the X-ray micro-computed tomography(X-rayμCT),spherical harmonical-based principal component analysis(SH-PCA),and discrete element method(DEM)were incorporated to generate virtual samples with morphological gene mutation at different length *** samples were subjected to axial compression and constant confining *** effects of multiscale particle morphology on the stress-strain and energy storage/dissipation responses of granular soils were *** is found that:(a)the effects of particle morphology on the initial stiffness,stress-strain,volumetric strain,and frictional energy dissipation behaviours are more pronounced for looser samples than for denser ones;(b)among different length scales,the particle morphology at the local roundness-level outperforms the one at the general form-level in dictating the macro-scale responses of granular soils;(c)the energy dissipation of a granular assemblage is a result of competition between particle morphology and initial void ratio.

关键词： X-ray micro-computed tomography(X-rayμCT) Spherical harmonic analysis(SHA) Discrete element method(DEM) Morphological gene mutation Energy dissipation

Metastatic suppressor genes inactivated by aberrant methylation in gastric cancer

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World Journal of Gastroenterology 2007年第43期13卷 5692-5698页

作者： jian-feng wang Dong-Qiu Dai Department of Surgical Oncology the FirstAffiliated Hospital China Medical University Dalian UniversityAffiliated Xinhua Hospital Shenyang 110001 Liaoning ProvinceChina Department of Surgical Oncology the FirstAffiliated Hospital China Medical University Shenyang 110001Liaoning Province China

AIM: To screen out the differentially methylated DNA sequences between gastric primary tumor and metastatic lymph nodes, test the methylation difference of gene PTPRG between primary gastric tumor and metastatic lymph nodes, and test the regulatory function of 5-aza- 2-deoxycytidine which is an agent with suppression on methylation and the level of methylation in gastric cancer cell line. METHODS: Methylated DNA sequences in genome were enriched with methylated CpG islands amplification (MCA) to undergo representational difference analysis (RDA), with MCA production of metastatic lymph nodes as tester and that of primary tumor as driver. The obtained differentially methylated fragments were cloned and sequenced to acquire the base sequence, which was analyzed with bioinformatics. With methylation-specific PCR (MSP) and RT-PCR, methylation difference of gene PTPRG was detected between primary tumor and metastatic lymph nodes in 36 cases of gastric cancer. Methylation of gene PTPRG and its regulated expression were observed in gastric cancer cell line before and after being treated with methylation-suppressive agent. RESULTS: Nineteen differentially methylated sequences were obtained and located at 5' end, exons, introns and 3' end, in which KL59 was observed to be located at 9p21 as the first exon of gene p16 and KL22 to be located at promoter region of PRPRG . KL22, as the probes, was hybridized with driver, tester and 3-round RDA products respectively with all positive signals except with the driver. Significant difference was observed in both methylation rate of gene PTPRG and PTPRG mRNA expression rate between primary tumor and metastatic lymph nodes. Demethylation of gene PTPRG, with recovered expression of PTPRG mRNA, was observed after gastric cancer cell line being treated with methylation-suppressive agent. CONCLUSION: Difference exists in DNA methylation between primary tumor and metastatic lymph nodes of gastric cancer, with MCA-RDA as one of the good anal

关键词： Gastric cancer Methylated CpG islandsamplification Representational difference analysis DNA methylation gene PTPRG

DNA barcoding of genus Toxoptera Koch （Hemiptera： Aphididae） Identification and molecular phylogeny inferred from mitochondrial COl sequences

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Insect Science 2009年第6期16卷 475-484页

作者： jian-feng wang Ge-Xia Qiao Institute of Zoology Chinese Academy of Sciences Beijing College of Biological and Environmental Engineering Shenyang University Shenyang China

Identification of aphid species is always difficult due to the shortage of easily distinguishable morphological characters. Aphid genus Toxoptera consists of species with similar morphology and similar to Aphis in most morphological characters except the stridulatory apparatus. DNA barcodes with 1 145 bp sequences of partial mitoehondrial cytochrome-coxidase I （COI） genes were used for accurate identification of Toxoptera. Results indicated mean intraspecific sequence divergences were 1.33%, whereas mean interspecific divergences were greater at 8.29% （0.13% and 7.79% if T. aurantii 3 and T. aurantii 4 are cryptic species）. Sixteen samples were distinguished to four species correctly by COI barcodes, which implied that DNA barcoding was successful in discrimination of aphid species with similar morphology. Phylogenetic relationships among species of this genus were tested based on this portion of COI sequences. Four species of Toxoptera assembled a clade with low support in maximum-parsimony （MP） analysis, maximumlikelihood （ML） analysis and Bayesian phylogenetic trees, the genus Toxoptera was not monophyletic, and there were two sister groups, such as T. citricidus and T. victoriae, and two clades of T. aurantii which probably presented cryptic species in the genus.

关键词： Aphididae barcoding citrus aphid COI molecular phylogeny Toxoptera

A Berry-Esseen Theorem and a Law of the Iterated Logarithm for Asymptotically Negatively Associated Sequences

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Acta Mathematica Sinica,English Series 2007年第1期23卷 127-136页

作者： jian feng wang Li Xin ZHANG Department of Statistics Zhejiang Gongshang University Hangzhou 310035 P R China Department of Mathematics Zhejiang Unversity Hangzhou 310028 P. R. China

Negatively associated sequences have been studied extensively in recent years, Asymptotically negative association is a generalization of negative association, In this paper a Berry Esseen theorem and a law of the ite... 详细信息

关键词： Berry-Esseen theorem law of the iterated logarithm negative association asymptotically negative association

Stray light analysis of the Xinglong 2.16-m telescope

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Research in Astronomy and Astrophysics 2020年第3期20卷 50-61页

作者： Tao-Ran Li jian-feng wang Xiao-Ming Zhang Yong Zhao jian-feng Tian Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

An effort towards understanding the problems associated with stray light related to the Xinglong2.16-m telescope is presented to estimate the stray light performance of the telescope itself and provide a method for improving stray light *** light analysis for the 2.16-m telescope model,which consists of an onion shaped dome,telescope structure,equatorial mount and telescope optics,has been developed in two cases(1)pointing to 60?and(2)pointing to zenith,in both azimuth and elevation *** Point Source Normalized Irradiance Transmittance(PSNIT),which is generally used for assessing stray light and is uncorrelated to entrance aperture,is calculated with a series of off-axis *** shows that the PSNIT values are less than 10-7 when off-axis angles are larger than±20?.The dominant contributors to stray light(primary and secondary mirror,telescope structure and dome)are identified to guide performance *** analyses indicate that significant benefit can be realized by adding only five vanes inside the bottom portion of the secondary *** the case of pointing to zenith,the PSNIT values will decrease about 40%on average.

关键词： telescope scattering methods:data analysis

The Toughening Behavior of the PP/POE Alternating Multilayered Blends under EWF and Impact Tensile Methods

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Chinese Journal of Polymer Science 2015年第10期33卷 1477-1490页

作者： Chun-hai Li jian-feng wang Ji-wei Guo 吴宏郭少云 The State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University

The multilayered polypropylene （PP） and poly（ethylene-co-octene）（POE） sheets were prepared by the microlayered co-extrusion system. The essential work of fracture （EWF） and the impact tensile methods have been successfully used to evaluate the toughening behaviors of the PP/POE multilayered blends under quasi-static and dynamic uniaxial tensile stress, respectively. The experimental results indicate that the multilayered structure plays a key role in the toughening behaviors. On increasing the layer number of the multilayered blends, the specific essential work of fracture, we, increases obviously. As for the flwp, there is no obvious variation in the multilayered blends with low POE content （6.79%）, however, obvious enhancement is observed with increasing the layer number of the high POE content multilayered blends （16.57%）. Compared with the conventional blends, the multilayered blends with 6.79% POE content are effective to increase the value of we. Additionally, the multilayered blends with high layer numbers present absolute advantage in improving the impact tensile values.

关键词： Multilayer EWF Impact tensile PP POE