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INVESTIGATION OF RELATIONSHIP BETWEEN ACOUSTIC EMISSION PARAMETERS AND TOOL WEAR IN METAL CUTTING

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Chinese Journal of Aeronautics 1992年第2期 83-88页

作者： Cao lin-xiang,zhang Ke,Wang Hong(Northwestern Polytechnical University)

Theoretical analysis and experimental research are done for exploring the relationshipbetween acoustic emission signal and tool wear in metal cutting process,and the relationshipbetween values of characteristics concerning acoustic emission signal and the valueof tool wear is *** this paper,it is suggested that the cumulative mean ■ andthe cumulative standard deviation σ,which are the cumulative values of maximum peakvoltage Vvs.t in a record length,may be used as real time and in-process recognitionof values of characteristics for tool wear so that realizing prediction control for toolwear may be possible.

关键词： INVESTIGATION OF RELATIONSHIP BETWEEN ACOUSTIC EMISSION PARAMETERS AND TOOL WEAR IN METAL CUTTING

Cisplatin-induced premature senescence with concomitant reduction of gap junctions in human fibroblasts

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Cell Research 2004年第1期14卷 60-66页

作者： Wei ZHAO, Zhong xiang lin, Zhi Qian zhang Peking University School of Oncology, and Beijing Institute for Cancer Research, Beijing 100034, China. lin ZX Peking Univ Sch Oncol Beijing 100034 Peoples R China

To examine the role of gap junctions in cell senescence, the changes of gap junctions in cisplatin-induced premature senescence of primary cultured fibroblasts were studied and compared with the replicative senescent human fibroblasts. Dye transfer assay for gap junction function and immunofluorescent staining for connexin 43 protein distribution were done respectively. Furthermore, cytofluorimetry and DAPI fluorescence staining were performed for cell cycle and apoptosis analysis, p53 gene expression level was detected with indirect immunofluorescence. We found that cisplatin (10 mM) treatment could block cell growth cycle at G1 and induced premature senescence. The premature senescence changes included high frequency of apoptosis, elevation of p53 expression, loss of membranous gap junctions and reduction of dye-transfer capacity. These changes were comparable to the changes of replicative senescence of human fibroblasts. It was also concluded that cisplatin could induce premature senescence concomita

关键词： cisplatin premature senescence gap junction intercellular communication connexin 43 fibroblasts.

Effect of heparin on high glucose induced proliferation and expression of matrix metalloproteinases in normal human mesangial cells

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Journal of Central South University of Technology 2005年第z1期12卷 359-364页

作者： ZHOU Qiao-ling Yasumoto Yuichiro Tsukamoto Masatoshi Nozaki Tsuyoshi Sogabe Atsushi Harada Kouji zhang Yi-xiang lin Xiao-yan zhang Yang-de Arima Terukatsu Second Department of Internal Medicine Kagoshima University Kagoshima Japan Department of Nephrology Xiangya Hospital Central South University Changsha 410008 China Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Second Department of Internal Medicine Kagoshima University Kagoshima Japan Department of Nephrology Xiangya Hospital Central South University Changsha 410008 China Second Department of Internal Medicine Kagoshima University Kagoshima Japan

Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological *** precise mechanism is not fully known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase, and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro. The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture medium were 0, 25, 50,100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium. They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed a 0. 61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when compared to cells grown without heparin. In Western blot analysis,MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high glucose medium. Incubation of heparin further increased expression of MMP1,

关键词： matrix metalloproteinases normal human mesangial cell glucose heparin

Perceptual MVDR-based cepstral coefficients(PMCCs)for speaker recognition

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Chinese Journal of Acoustics 2012年第4期31卷 489-498页

作者： LIANGChunyan zhang xiang YANG lin zhang Jianping YAN Yonghong Key Laboratory of Speech Acoustics and Content Understanding Chinese Academy of Sciences Institute of Acoustics CAS Beijing 100190

A feature extraction technique named perceptual MVDR-based cepstral coefficients （PMCCs） was introduced into speaker recognition. PMCCs are extracted and modeled using Gaussian Mixture Models （GMMs） for speaker recognition. In order to compensate for speaker and channel variability effects, joint factor analysis （JFA） is used. The experiments are carried out on the core conditions of NIST 2008 speaker recognition evaluation data. The experimental results show that the systems based on PMCCs can achieve comparable performance to those based on the conventional MFCCs. Besides, the fusion of the two kinds of systems can make significant performance improvement compared to the MFCCs system alone, reducing equal error rate （EER） by the factor between 7.6% and 30.5% as well as minimum detect cost function （minDCF） by the factor between 3.2% and 21.2% on different test sets. The results indicate that PMCCs can be effectively applied in speaker recognition and they are complementary with MFCCs to some extent.

关键词：说话人识别 MVDR 倒谱系数 CCs系统感知高斯混合模型提取技术性能改善

A short-term magnetic resonance imaging analysis of acetabular adaptation in developmental dysplasia of the hip by open reduction or open reduction combined with Dega osteotomy

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Chinese Medical Journal 2021年第13期134卷 1619-1621页

作者： Yan Meng Zhao Lu xiang-lin zhang Lian-Yong Li Shi-Nong Pan Department of Radiology Shengjing Hospital of China Medical UniversityShenyangLiaoning 110004China Department of Radiology The First Affiliated Hospital of Jinzhou Medical UniversityJinzhouLiaoning 121000China Department of Pediatric Orthopedics Shengjing Hospital of China Medical UniversityShenyangLiaoning 110004China

Developmental dysplasia of the hip(DDH)is one of the most common limb deformities in pediatric *** who cannot achieve closed reduction,or cannot maintain concomitant reduction,suffer from repeated dislocation or delay... 详细信息

关键词： dysplasia diagnosis maintain

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精冲模具崩刃失效演变及机理分析

塑性工程学报 2018年第5期25卷 33-38页

作者：张祥林张丽筠华中科技大学材料成形与模具技术国家重点实验室

从精冲模具崩刃失效的观测出发,利用体式显微镜、光学显微镜、环境扫描电子显微镜等设备,清晰显示了薄壁冲头和齿形冲头崩刃刃口附近侧面和底部的微裂纹、凹坑和变形形貌;结合文献理论、生产体验和形貌图分析了崩刃失效的演变规律、崩... 详细信息

从精冲模具崩刃失效的观测出发,利用体式显微镜、光学显微镜、环境扫描电子显微镜等设备,清晰显示了薄壁冲头和齿形冲头崩刃刃口附近侧面和底部的微裂纹、凹坑和变形形貌;结合文献理论、生产体验和形貌图分析了崩刃失效的演变规律、崩刃失效机制等。结果表明：冲头应力集中的重载导致的塑性变形是侧面主裂纹萌生的主要根源,挤压和拉拔力促进了裂纹的扩展,主裂纹汇合引起崩刃失效。最后根据影响精冲模具崩刃失效的因素,由生产现场实用化的角度,从被加工零件材料及形状、模具材料及结构、模具受力平衡性等方面给出了延缓模具崩刃失效的有效措施。

关键词：精冲模具崩刃裂纹

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近完全二部图的交叉数

数学学报（中文版） 2023年第6期66卷 1147-1166页

作者：王雨溪吕胜祥张湘林湖南财政经济学院数学与统计学院长沙410205

图G的交叉数是刻画图的非平面性的一个重要参数.它是指图G在平面上的所有画法中边与边之间交叉数目的最小值.确定具体图类的交叉数是图的交叉数问题中一个经典的研究方向.Zarankiewicz于1954年提出了完全二部图交叉数的猜想:cr(Km,n)=[2... 详细信息

图G的交叉数是刻画图的非平面性的一个重要参数.它是指图G在平面上的所有画法中边与边之间交叉数目的最小值.确定具体图类的交叉数是图的交叉数问题中一个经典的研究方向.Zarankiewicz于1954年提出了完全二部图交叉数的猜想:cr(Km,n)=[2/m][2/m-1][2/n][2/n-1].1971年,Kleitman证明了当min{m,n}≤6时,上式成立.由于其难度,完全二部图交叉数的研究进展是较缓慢的.至今,完全二部图K_(7,n)(n≥11)的交叉数都还未确定.然而,我们发现研究近完全二部图的交叉数可了解在完全二部图中加边与完全二部图交叉数的增长程度之间的关系.因此,为了促进完全二部图交叉数的研究,本文借助旋系与交叉数之间的关系、图的结构性质以及图的顶点度局部修改法确定了五个近完全二部图的交叉数.

关键词：画法交叉数联图旋系完全二部图

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根点自粘合后图的亏格分布

数学学报（中文版） 2016年第1期59卷 133-144页

作者：张湘林黄元秋郭婷湖南师范大学数学与计算机科学学院长沙410081 湖南城市学院数学与计算科学学院益阳413000

利用删点、加边原理,多种乘法法则,自粘合定理给出了一个双根图在其中一个根点的度为任意大的情形下根点自粘合后图的亏格分布,推广了Gross在文[Genus distribution of graph amalgamations:self-pasting at root-vertices,***.,2011,49... 详细信息

利用删点、加边原理,多种乘法法则,自粘合定理给出了一个双根图在其中一个根点的度为任意大的情形下根点自粘合后图的亏格分布,推广了Gross在文[Genus distribution of graph amalgamations:self-pasting at root-vertices,***.,2011,49:19-38]中"两个根点度均为2"的类似结果.

关键词：亏格分布自粘合删点原理加边原理

Dielectric-ion-conductive ZnNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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Journal of Energy Chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang Jian Wang Panpan zhang Xiaomin Cheng Qinghua Guan Jing Dong Bixian Chen Lujie Jia Jing zhang Yongzheng zhang Yunjian Liu Hongzhen lin School of Materials Science and Engineering Jiangsu University i-Lab & CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Helmholtz Institute Ulm (HIU) Karlsruhe Institute of Technology (KIT) School of Materials Science and Engineering Xi'an University of Technology State Key Laboratory of Chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AZMBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn（H2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface （ZNB@Zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.

关键词： Zn metal battery Dielectric artificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition