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Effect of reinforcement content on the adhesive wear behavior of Cu10Sn.n./Si3n4 composites produced by stir casting

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 1052-1060页

作者： K.Sanesh S.Shiam Sunder n.Radhika Department of Mechanical Engineering Amrita School of EngineeringCoimbatore 64112Amrita Vishwa VidyapeethamAmrita UniversityIndia

The main objective of this paper was to fabricate CuSnni alloy and its composites reinforced with various contents of Sinparticles(5wt%, 10wt%, and 15wt%) and to investigate their dry sliding wear behavior using a pin.on-disk tribometer. Microstructural examinations of the specimens revealed a uniform dispersion of Sinparticles in the copper matrix. Wear experiments were performed for all combinations of parameters, such as load(10, 20, and 30 n), sliding distance(500, 1000, and 1500 m), and sliding velocity(1, 2, and 3 m/s), for the alloy and the composites. The results revealed that wear rate increased with increasing load and increasing sliding distance, whereas the wear rate decreased and then increased with increasing sliding velocity. The primary wear mechanism encountered at low loads was mild adhesive wear, whereas that at high loads was severe delamination wear. An oxide layer was formed at low velocities, whereas a combination of shear and plastic deformation occurred at high velocities. The mechanism at short sliding distances was ploughing action of Sinparticles, which act as protrusions; by contrast, at long sliding distances, direct metal–metal contact occurred. Among the investigated samples, the Cu/10wt% Sincomposite exhibited the best wear resistance at a load of 10 n, a velocity of 2 m/s, and a sliding distance of 500 m.

关键词： copper matrix composites stir casting adhesive wear wear mechanisms

A HYBRID APPROACH FOR MInIMIZInG MAKESPAn In PERMUTATIOn FLOWSHOP SCHEDULInG

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Journal of Systems Science and Systems Engineering 2017年第1期26卷 50-76页

作者： Kann.n.Govindan R'Balasundaram n.Baskar e.Asokan Center for Sustainable Engineering Operations Management Department of Technology and Innovation University of Southern Denmark Odense M Denmark-5230 Department of Mechanical Engineering K.Ramakrishnan College of Engineering Tiruchirappalli Tamilnadu India Pin-621112 Department of Mechanical Engineering Saranathan College of Engineering Tiruchirappalli Tamilnadu India Pin 620012 Department of Production Engineering National Institute of Technology Tiruchirappalli Tamilnadu India Pin-620015

This work proposes a hybrid approach for solving traditional flowshop scheduling problems to reduce the makespan （total completion time）. To solve scheduling problems, a combination of Decision Tree （DT） and Scatter Search （SS） algorithms are used. Initially, the DT is used to generate a seed solution which is then given input to the SS to obtain optimal / near optimal solutions of makespan. The DT used the entropy function to convert the given problem into a tree structured format / set of rules. The SS provides an extensive investigation of the search space through diversification. The advantages of both DT and SS are used to form a hybrid approach. The proposed algorithm is tested with various benchmark datasets available for flowshop scheduling. The statistical results prove that the proposed method is competent and efficient for solving flowshop problems.

关键词： Flowshop scheduling makespan decision tree algorithm scatter search algorithm hybrid algorithm

Enhancing Air Quality Forecasts over Catalonia(Spain)Using Model Output Statistics

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Journal of Geoscience and Environment Protection 2015年第8期3卷 9-22页

作者： Víctor Andrés Pérez Raúl Arasa Bernat Codina Jesica pin.n Technical Department Meteosim S.L.BarcelonaSpain Department of Astronomy and Meteorology University of BarcelonaBarcelonaSpain

Model Output Statistics (MOS) is a well-known technique that allows improving outputs from numerical atmospheric models. In this contribution, we present the development of a MOS algorithm to improve air quality forecasts in Catalonia, a region in the northeast of Spain. These forecasts are obtained from an Eulerian coupled air quality modelling system developed by Meteosim. nitrogen Dioxide (nO2), Particulate Matter (PM10) and Ozone (03) have been the pollutants considered and the methodology has been applied on statistical values of these pollutants according to regulatory levels. Four MOS algorithms have been developed, characterized by different approaches in relation with seasonal stratification and stratification according to the measurement stations considered. Algorithms have been compared among them in order to obtain a MOS that reduces the forecast uncertainties. Results obtained show that the best MOS designed increases the accuracy of nO2 maximum 1-h daily value forecast from 71% to 75%, from 68% to 81% in the case of daily values of PM10, and finally, the accuracy of O3 maximum 1-h daily value from 79% to 87%.

关键词： Air Quality Modelling Forecasting Model Output Statistics(MOS)

Second Law Analysis and Optimization of Elliptical pin.Fin Heat Sinks Using Firefly Algorithm

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Computers, Materials & Continua 2020年第11期65卷 1015-1032页

作者： nawaf n.Hamadneh Waqar A.Khan Ilyas Khan Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia Department of Mechanical Engineering College of EngineeringPrince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh City72915Vietnam

One of the most significant considerations in the design of a heat sink is thermal management due to increasing thermal flux and miniature in *** heat sinks utilize plate or pin.fins depending upon the required heat dissipation *** are designed to optimize overall *** pin.fin heat sinks enhance heat transfer rates and reduce the pumpin. *** this study,the Firefly Algorithm is implemented to optimize heat sinks with elliptical *** pin.fins are arranged in an inline *** nature-inspired metaheuristic algorithm performs powerfully and efficiently in solving numerical global optimization *** on mass,energy,and entropy balance,three models are developed for thermal resistance,hydraulic resistance,and entropy generation rate in the heat *** major axis is used as the characteristic length,and the maximum velocity is used as the reference *** entropy generation rate comprises the combined effect of thermal resistance and pressure *** total EGR is minimized by utilizing the firefly *** optimization model utilizes analytical/empirical correlations for the heat transfer coefficients and friction *** is shown that both thermal resistance and pressure drop can be simultaneously optimized using this *** is demonstrated that the performance of FFA is much better than PPA.

关键词： Firefly algorithm mathematical models entropy generation rate elliptical pin.fin heat sinks thermal resistance pressure drop

Frequency Response Optimization of Dual Depletion InGaAs/InP pin.Photodiodes

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Photonic Sensors 2016年第1期6卷 63-70页

作者： J. M. Torres PEREIRA Joao Paulo n. TORRES Instituto de Telecomunicacoes Instituto Superior Tecnico-Universidade de Lisboa Lisboa Portugal

The frequency response of a dual depletion p-i-n （pin. photodiode structure is investigated. It is assumed that the light is incident on the n side and the drift region is located between the n contact and the absorption region. The numerical model takes into account the transit time and the capacitive effects and is applied to photodiodes with n.n.uniform illumination and linear electric field profile. With an adequate choice of the device＇s structural parameters, dual depletion photodiodes can have larger bandwidths than the conventional pin.devices.

关键词： pin.photodiodes dual depletion frequency response modeling

Hydroxychavicol,a polyphenol from Piper betle leaf extract,induces cell cycle arrest and apoptosis in TP53-resistant HT-29 colon cancer cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2021年第2期22卷 112-122页

作者： Aiysvariyah RAJEDADRAM Kar Yong pin.Sui Kiong LInG See Wan YAn Mee Lee LOOI School of Biosciences Taylor’s UniversityLakeside Campus47500Subang JayaMalaysia Forest Research Institute Malaysia 52109KepongMalaysia Department of Biomedical Science Faculty of MedicineUniversity of Malaya50603Kuala LumpurMalaysia

This study aims to elucidate the antiproliferative mechanism of hydroxychavicol(HC).Its effects on cell cycle,apoptosis,and the expression of c-Jun.n.terminal kinase(JnK)and P38 mitogen-activated protein kinase(MAPK)in HT-29 colon cancer cells were *** was isolated from Piper betle leaf(PBL)and verified by high-performance liquid chromatography(HPLC),nuclear magnetic reson.n.e(nMR),and gas chromatography-mass spectrometry(GC-MS).The cytotoxic effects of the standard drug 5-fluorouracil(5-FU),PBL water extract,and HC on HT-29 cells were measured after 24,48,and 72 h of *** cycle and apoptosis modulation by 5-FU and HC treatments were investigated up to 30 *** in phosphorylated JnK(pJnK)and P38(pP38)MAPK expression were observed up to 18 *** half maximal inhibitory concentration(IC_(50))values of HC(30μg/mL)and PBL water extract(380μg/mL)were achieved at 24 h,whereas the IC_(50)of 5-FU(50μmol/L)was obtained at 72 *** cycle arrest at the G0/G1 phase in HC-treated cells was observed from12 h *** apoptotic cell death in HC-treated cells compared to 5-FU-treated cells(Pn of pJnK and pP38 MAPK was observed at 12 h in HC-treated cells,but not in 5-FU-treated HT-29 cells(Pncluded that HC induces cell cycle arrest and apoptosis of HT-29 cells,with these actions possibly mediated by JnK and P38 MAPK.

关键词： Piper betle Hydroxychavicol(HC) Cell cycle Apoptosis c-Jun.n.terminal kinase(JnK) P38 mitogen-activated protein kinase(MAPK)

Microstructural evolution of ECAPed 1050 alloy under magnetic annealing

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International Journal of Minerals,Metallurgy and Materials 2014年第12期21卷 1205-1214页

作者： Yi-heng Cao pin.feng Jia Kang Wang Li-zi He pin. Wang Jian-zhong Cui Key Lab of Electromagnetic Processing of Materials Ministry of Education Northeastern University

Hardness and microstructure evolutions in 1050 aluminum alloy prepared by equal-channel angular pressing （ECAP） were inves- tigated by hardness testing, optical microscopy, and transmission electron microscopy after samples were annealed at different temperatures for 1 h both in the absence and presence of a 12-T magnetic field. The results showed that the hardness of samples after magnetic annealing were lower than that of samples after normal annealing at 150-250℃, but it was higher than that of samples after normal annealing at 〉250℃. During annealing, the rate of soften.n. was faster, and the grains were more homogeneous in 8-ECAPed samples than in 2-ECAPed samples. A rapid grain growth occurred when 2-ECAPed samples were annealed at high temperature （〉300℃）. The magnetic field enhanced the mobility of dislocations and grain boundaries. A more homogeneous grain size was observed in samples prepared under an applied magnetic field.

关键词： aluminum alloys magnetic annealing equal channel angular pressing microstructural evolution grain growth

Phase Ⅱ study of apatinib in combination with oral vinorelbine in heavily pretreated HER2-negative metastatic breast cancer and clinical implications of monitoring ctDnA

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Cancer Biology & Medicine 2021年第3期18卷 875-887页

作者： Anjie Zhu Peng Yuan.n.nlin Hu Mingzhou Li Wenmiao Wang Xue Wang Jian Yue Jiayu Wang Yang Luo Fei Ma pin.Zhang Qing Li Binghe Xu Shanbo Cao Giuseppe Lippi Yoichi naito Mohammed A.Osman Gustavo n.Marta Gianluca Franceschini Armando Orlandi Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of BreastOncologyPeking University Cancer Hospital&InstituteBeijing 100142China Department of VIP Medical Services National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Pathology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Acorn Med Biotechnology Co. Ltd.Beijing 101102China Section of Clinical Biochemistry University Hospital of VeronaVeronaVerona 37100Italy Department of Breast and Medical Oncology National Cancer Center Hospital EastKashiwa 277-8577Japan Clinical Oncology General Organization for Teaching HospitalsCairo 11435Egypt Department of Radiation Oncology Hospital Sírio-LibanêsSao Paulo 01308-050Brazil Multidisciplinary Breast Center Fondazione Policlinico Universitario A.Gemelli IRCCSUniversitàCattolica del Sacro CuoreRome 00176Italy Unit of Medical Oncology Fondazione Policlinico Universitario A.Gemelli IRCCSRoma 00176Italy

Objective:Apatinib is an oral TKI targeting ***-agent apatinib treatment has been shown to produce an objective response in patients with pretreated m *** vinorelbine also holds promise as a treatment of choice in patients with m *** study aimed to investigate the efficacy and safety of the oral vinorelbine-apatinib combination in patients with pretreated m *** addition,we detected gene variants in ct DnA to explore the therapeutic ***:This study enrolled patients with HER2-negative m BC who were pretreated with anthracycline/*** were treated with apatinib at 500 mg/425 mg daily plus oral vinorelbine 60 mg/m2 on days 1,8,and 15 of every cycle(3 weeks).The primary endpoint was *** secondary endpoints were ORR,CBR,OS,and *** eligible for ct DnA detection were evaluated before and during ***:Forty patients were *** median PFS was 5.2 months(95%CI,3.4–7.0 months),and the median OS was 17.4 months(95%CI,8.0–27.0 months).The ORR was 17.1%(6/35),and the CBR was 45.7%(16/35).The most common AEs included gastrointestinal reaction,myelosuppression,and *** 20 patients,ct DnA was detected at baseline and during treatment.A significant difference was found in PFS for undetected *** baseline ct DnA(13.9 months vs.3.6 months,P=0.018).Conclusions:All-oral therapy with apatinib plus vinorelbine displayed objective efficacy in patients with heavily pretreated HER2-negative m BC,with acceptable and manageable toxicity *** with no gene variant detected and lower variant allele frequencies in ct DnA at baseline showed longer PFS.

关键词： Metastatic breast cancer apatinib oral vinorelbine ct DnA

Optimization of process parameters to maximize ultimate tensile strength of friction stir welded dissimilar aluminum alloys using response surface methodology

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Journal of Central South University 2013年第11期20卷 2929-2938页

作者： R.Palanivel P.Koshy Mathews n.Murugan Kalaivani College of Technology Coimbatore Institute of Technology

Aluminium alloys generally present low weldability by traditional fusion welding *** of the friction stir welding(FSW)has provided an alternative improved way of producing aluminium joints in a faster and reliable *** quality of a weld joint is stalwartly influenced by process parameter used during *** approach to develop a mathematical model was studied for predicting and optimizing the process parameters of dissimilar aluminum alloy(AA6351 T6 AA5083 H111)joints by incorporating the FSW process parameters such as tool pin.profile,tool rotational speed welding speed and axial *** effects of the FSW process parameters on the ultimate tensile strength(UTS)of friction welded dissimilar joints were *** was carried out to maximize the UTS using response surface methodology(RSM)and the identified optimum FSW welding parameters were reported.

关键词：优化工艺参数摩擦搅拌焊接极限拉伸强度响应曲面法异种接头铝合金搅拌摩擦焊焊接工艺参数