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Fabrication and Mechanical Properties of TiC/TiAl Composites

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Journal of wuhan University of Technology(Materials Science) 2004年第1期19卷 1-4页

作者：岳云龙 Jinan University

TiC/TiAl composites with different TiC content were fabricated by rapid heating technique of spark plasma sintering (SPS). The effect of TiC particles on microstructure and mechanical properties of TiAl Matrix was investigated. The results indicate that grain sizes of TiAl matrix decrease and mechanical properties are improved because of the addition of TiC particles. The composites display a 26.8% increase in bending strength when 10 wt% TiC is added and 43.8% improvement in fracture toughness when 5 wt% TiC is added compared to values of TiC-free materials. Grain-refinement and dispersion-strengthening were the main strengthening mechanism. The improvement of fracture toughness was due to the deflexion of TiC particles to the crack.

关键词： TiC/TiAl composiles mechanical properties SPS sintering technique

Plasma D(-)-lactate as a new marker for diagnosis of acute intestinal injury following ischemia-reperfusion

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World Journal of Gastroenterology 1997年第4期3卷 27-29页

作者： YAO YongMing1, YU yan1, wu Ye2, LU LianRong1 and SHENG ZhiYong1

IM To observe the kinetics of D()lactate alteration in both portal and systemic circulations, and its relationship with intestinal injury in rats subjected to acute intestinal ischemiareperfusion.METHODS Anesthetized rats underwent 75min superior mesenteric artery occlusion followed by 6hour reperfusion. Plasma D()lactate levels were measured by an enzymatic spectrophotometric assay.RESULTS Intestinal ischemia for 75 min resulted in a significant elevation of D()lactate levels in portal vein as compared with the baseline values (P15, P1). In addition,there was a remarkable rise of endotoxin concentration within the portal vein at the end of 75min ischemia (P<005), reaching a peak at 2 hours postreperfusion.CONCLUSION Acute intestinal ischemia is associated with failure of mucosal barrier resulting in increased plasma D()lactate levels in both portal and systemic blood. The subsequent reperfusion might further increase D()lactate levels, which are correlated to the macropathological alterations. Plasma D()lactate may be a useful marker of intestinal injury following both ischemia and reperfusion insults.

关键词： D()lactate endotoxin intestinal injury reperfusion injury

Periodontal status and associated risk factors among childbearing age women in Cixi City of China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第3期14卷 231-239页

作者： yan-min wu Jia LIU Wei-lian SUN Li-li CHEN Li-guo CHAI Xiang XIAO Zheng CAO Department of Oral Medicine the Second Affiliated HospitalSchool of MedicineZhejiang University Department of Oral Medicine Cixi Huayang Dental Hospital Department of Dentistry Sir Run Run Shaw HospitalSchool of MedicineZhejiang University

Objective:To investigate the periodontal status and associated risk factors among women of childbearing age to increase the awareness of oral ***:The study was conducted on childbearing age women in Cixi,a city in Zhejiang Province in the southeast of China.A total of 754 women participated in periodontal examination while receiving prenatal *** of the women were collected from the Cixi Family Planning Commission and during an *** periodontal indices,such as bleeding on probing(BOP),probing depth(PD),and clinical attachment level(CAL) were measured during the *** analysis on subject-based data was ***:The prevalence of periodontal disease among childbearing age women in Cixi was high(84.7%).A significant association was found between the disease and educational level,pregnancy,taking oral contraceptives,stress,alcohol consumption,overweight,dental visit,and teeth brushing(P1 min(P1) after adjusting for age and ***:The periodontal status of childbearing age women in Cixi needs to be improved *** towards the periodontal health should be warranted,especially for those in special statuses and with poor awareness.

关键词： Periodontal status Childbearing age women Risk factors Pregnancy

Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： Yin wu yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

Advancing from scalar to vectorial liquid crystal holography:a paradigm shift

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Light(Science & Applications) 2024年第9期13卷 1696-1697页

作者： yan Li Shin-Tson wu Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Optics and Photonics University of Central FloridaOrlandoFL 32816USA

A versatile and tunable vectorial holography is demonstrated based on single-layer single-material liquid crystal *** novel approach advances the process from scalar to vectorial holography,opening new opportunities f... 详细信息

关键词： liquid crystal versatile

Numerical Investigation on Characteristics of Supercritical CO_(2)Heat Transfer in Vertical Circular Tubes with Circumferentially Half-Side Heating

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Journal of Thermal Science 2024年第5期33卷 1744-1756页

作者： ZHANG yan ZHANG Xinyi yan Chenshuai wu Wenhua GAO Erman School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The design of heat exchangers in the advanced supercritical power conversion system cannot be separated from the study of heat transfer ***-side heating mode is often encountered for solar receiver and supercritical ***,the characteristics of supercritical CO_(2)(sCO_(2))convection heat transfer in vertical tubes with circumferentially half-side heating was numerically investigated through the SST k-ωturbulent model which matches well with the experimental ***,heat transfer between sCO_(2)upflow and downflow was *** to film boiling heat transfer at subcritical pressure,numerical results were processed according to the supercritical pseudo-phase transition hypothesis,with liquid-like phase in the tube core region and vapor-like film in the region near the heated tube *** structure of two layers was demarcated by pseudo-critical temperature T_(pc).Therefore,sCO_(2)heat transfer was assessed according to double thermal resistances caused by vapor-like film near the wall and core liquid-like *** findings suggest that wall temperature for upflow is higher than that for downflow,which is attributed to larger thermal resistance in the fluid domain for upflow than that for *** difference guarantees the excellent heat transfer performance for downflow than *** is also further concluded that the formation of vapor-like film near the wall due to pseudo-phase transition plays a key role in dominating wall temperature and inducing heat transfer deterioration in half-side heating *** present contribution is significant to the design of supercritical heat exchanger under half-side heating mode.

关键词： supercritical CO_(2) pseudo-phase transition half-side heating thermal resistance flow direction

A Positive Analysis for BPR of the Third Party Logistics

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厦门大学学报（自然科学版） 2002年第S1期41卷 231-232页

作者： LI yan-feng 1, wu Xiao-song 2 (1. Management School, Huazhong University of Science and Technology, wuhan 430074, China 2. Information Management School, Yunnan University of Finance and Trade, Kunming 650221, China)

Facing the opportunities and challenges of China’s en try into WTO, logistics enterprises take BPR as an important way to improve the core *** modern logistics is a systematic engineering and its require ments are the standardization and normalization for enhancing the Chinese enterp rises’ level of logistic *** paper reveal the importance of manageme nt technique,information technique and business model in enterprise’s BPR throug h the positive analysis for business process of the third party logistics as a new system after reengineering businees process. Reorganization of marketing target. The characters of business procedure after N ew Sunshine recomposed include: "the last mile " service systems of logistics; s etting up HUB to control many end-points in big and middle cities, setting up s ingle-points in small cities, the small parts acting delivering system which st yle of "assembly and allot" are made of in. Reorganization of business model. The New Sunshine reorganized has three aspects of business model which set up: HUB, end-point and single-point. Reorganization of business *** mainly business process of restructure Ne w Sunshine include : standard quote declaring prices to all attendants; on line, timely and exactly declaring prices; The net contract of B2C work on line; Tran smit to attendant; Logistice operating; feedback the working information; User t rack goods condition; Settling information; paying and so on, the different busi ness can separate into kinds of right corresponding to the business process, suc h as the picture of distributing parcel, ordering, moving, picking, transporting , delivering, information, inquiring and settling. Set up standard systems. Aims to execute standard management is to make distribu te and logistics for norm and standard, according to the resources share tog ether with the progresses especially and base on reducing the necessary expenses to reduce the living expenses, while low cost

关键词： third party logistics management technique info rmation technique business model

Fast algorithm based on triplet Markov fields for unsupervised multi-class segmentation of SAR images

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Science China(Information Sciences) 2011年第7期54卷 1524-1533页

作者： wu yan 1,WANG Xin 1,XIAO Ping 2,GAN Lu 1,LIU Chunyan 1 & LI Ming 3 1 School of Electronics Engineering,Xidian University,Xi’an 710071,China 2 Shaanxi Bureau of Surveying & Mapping,Xi’an 710054,China 3 National Key Laboratory of Radar Signal Processing,Xidian University,Xi’an 710071,China School of Electronics Engineering Xidian University Xi’an China Shaanxi Bureau of Surveying & Mapping Xi’an China National Key Laboratory of Radar Signal Processing Xidian University Xi’an China

Non-Gaussian triplet Markov fields (TMF) model is suitable for dealing with multi-class segmentation of non-stationary and non-Gaussian synthetic aperture radar (SAR) *** the complexity of the model and algorithm,as well as the requirement of real-time,and robust and efficient processing of SAR images,a fast algorithm based on TMF for unsupervised multi-class segmentation of SAR images is proposed in this *** the speckle noise in SAR images,numerical characteristic,threshold selection and QuadTree decomposition criterion are researched *** the new method,a SAR image can quickly be mapped into an edge-based pixon-representation,which results in a coarse decomposition in smooth regions,and a fine decomposition in *** by combining TMF model with the pixon-representation of SAR image,a new potential energy function of TMF based on pixon-representation is ***,the segmentation is finished by Bayesian maximum posterior mode (MPM).The effectiveness of the fast TMF algorithm is demonstrated by applying it to simulated data and real SAR images.

关键词： pixon-representation of SAR image QuadTree decomposition new potential energy function triplet Markov fields multi-class segmentation

Global-local combined features to detect pain intensity from facial expression images with attention mechanism

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Journal of Electronic Science and Technology 2024年第3期22卷 80-93页

作者： Jiang wu Yi Shi Shun yan Hong-Mei yan yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China MOE Key Laboratory for Neuroinformation School of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengdu611731China College of Engineering University of California at Santa BarbaraSanta Barbara93106USA

The estimation of pain intensity is critical for medical diagnosis and treatment of *** the development of image monitoring technology and artificial intelligence,automatic pain assessment based on facial expression and behavioral analysis shows a potential value in clinical *** paper reports a framework of convolutional neural network with global and local attention mechanism(GLA-CNN)for the effective detection of pain intensity at four-level thresholds using facial expression ***-CNN includes two modules,namely global attention network(GANet)and local attention network(LANet).LANet is responsible for extracting representative local patch features of faces,while GANet extracts whole facial features to compensate for the ignored correlative features between *** the end,the global correlational and local subtle features are fused for the final estimation of pain *** under the UNBC-McMaster Shoulder Pain database demonstrate that GLA-CNN outperforms other state-of-the-art ***,a visualization analysis is conducted to present the feature map of GLA-CNN,intuitively showing that it can extract not only local pain features but also global correlative facial *** study demonstrates that pain assessment based on facial expression is a non-invasive and feasible method,and can be employed as an auxiliary pain assessment tool in clinical practice.

关键词： Attention Convolutional neural network Facial expression Pain intensity