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PrEPArATION AND CHArACTErIZATION OF AMIDATED PECTIN BASED POLYMEr ELECTrOLYTE MEMBrANES

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Chinese Journal of Polymer Science 2009年第5期27卷 639-646页

作者： r.K.Mishra A.Anis S.Mondal M.Dutt A.K.Banthia Department of Polymer Science Bundelkhand University Materials Science Center Indian Institute of Technology Department of Polymer Science Bundelkhand University

The work presents the synthesis and characterization of amidated pectin(AP) based polymer electrolyte membranes(PEM) crosslinked with glutaraldehyde(GA).The prepared membranes are characterized by Fourier transform infrared spectroscopy(FTIr),organic elemental analysis,X-ray diffraction studies(XrD),thermogravimetric analysis (TGA) and impedance *** properties of the membranes are evaluated by tensile *** degree of amidation(DA),molar and mass reaction yields(Y_M and K_N) are calcu...

关键词： Amidated pectin Proton conducting Methanol permeability Impedance spectroscopy Fuel cell.

COVID19: Forecasting Air Quality Index and Particulate Matter (PM2.5)

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Computers, Materials & Continua 2021年第6期67卷 3363-3380页

作者： r.Mangayarkarasi C.Vanmathi Mohammad Zubair Khan Abdulfattah Noorwali rachit Jain Priyansh Agarwal School of Information Technology and Engineering Vellore Institute of TechnologyVellore632007India Department of Computer Science College of Computer Science and EngineeringTaibah University41477Saudi Arabia Department of Electrical Engineering Umm Al Qura UniversityMakkah21955Saudi Arabia School of Computer Science and Engineering and Engineering Vellore Institute of TechnologyVellore632007India

Urbanization affects the quality of the air,which has drastically degraded in the past *** quality level is determined by measures of several air pollutant *** create awareness among people,an automation system that forecasts the quality is *** COVID-19 pandemic and the restrictions it has imposed on anthropogenic activities have resulted in a drop in air pollution in various cities in *** overall air quality index(AQI)at any particular time is given as the maximum band for any ***2.5 is a fine particulate matter of a size less than 2.5 micrometers,the inhalation of which causes adverse effects in people suffering from acute respiratory syndrome and other cardiovascular ***2.5 is a crucial factor in deciding the overall *** proposed forecasting model is designed to predict the annual PM2.5 and *** forecasting models are designed using Seasonal Autoregressive Integrated Moving Average and Facebook’s Prophet Library through optimal hyperparameters for better *** AQI category classification model is also presented using classical machine learning *** experimental results confirm the substantial improvement in air quality and greater reduction in PM2.5 due to the lockdown imposed during the COVID-19 crisis.

关键词： AQI PM2.5 COVID19 air quality in India AQI-forecasting

Sperm retrieval and intracytoplasmic sperm injection outcomes in men with cystic fibrosis disease versus congenital bilateral absence of the vas deferens

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Asian Journal of Andrology 2021年第2期23卷 140-145页

作者： J Abram McBride Taylor P Kohn Daniel J Mazur Larry I Lipshultz r Matthew Coward Scott Department of Urology Baylor College of MedicineHoustonTX 77030USA Department of Urology UNC School of MedicineChapel HillNC 27599USA UNC Fertility RaleighNC 27617USA

recent data suggest that cystic fibrosis transmembrane conductance regulator(CFTr)gene alterations negatively impact male fertility beyond *** sought to compare gene alterations,sperm retrieval rates,and intracytoplasmic sperm injection(ICSI)outcomes among men with cystic fibrosis(CF)disease and congenital bilateral absence of the vas deferens(CBAVD)*** retrospectively evaluated all men who underwent surgical sperm retrieval at two academic,high-volume andrology centers from 2010 to *** men with documented CFTr alterations and obstructive azoospermia from either CBAVD or CF were *** between groups for CFTr abnormality,sperm retrieval,and ICSI outcomes were statistically ***,39 patients were included with 10 in the CF and 29 in the CBAVD *** sperm retrieval rates were significantly lower in the CF group for sperm concentration(14.8×10^(6)ml^(-1)vs 61.4×10^(6)ml^(−1),P=0.02)and total motile sperm count(2.9 million vs 11.4 million,P=0.01).This difference was only predicted by homozygous delta F508 CFTr mutations(Proup also demonstrated a significantly higher rate of rescue testicular sperm extraction(70.0%vs 27.6%,Pr fertilization rate with ICSI(32.5%vs 68.9%,Prated lower sperm quality,greater difficulty with sperm retrieval,and worse ICSI outcomes compared with CBAVD-only *** delta F508 CFTr mutations appear to significantly impair spermatogenesis and sperm function.

关键词： congenital bilateral absence of the vas deferens cystic fibrosis intracytoplasmic sperm injection outcomes male infertility obstructive azoospermia

Contour representation based on wedgelet

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Journal of Systems Engineering and Electronics 2006年第2期17卷 251-257页

作者： Liu Zeyi~1, Sun Ziqiang~ 2,3 , Xu Ling~2 & Peng Xiang~ 4,5 1. Dept. of Mathematics of Science Coll., Shenzhen Univ., Shenzhen 518060, P.r. China 2. Dept. of Mathematics of Science Coll., Tianjin Univ., Tianjin 300072, P.r. Ch ina 3.Tianjin Foreign Studies Univ., Tianjin 300204, P.r. China 4. Inst. of Optoelectronics, Shenzhen Univ., Shenzhen 518060, P.r. China 5. National Lab of Precision Measurement Technology and Instrumentation, Tianjin 300072, P.r. China Dept. of Mathematics of Science Coll. Shenzhen Univ. Shenzhen 518060 P. R. China Dept. of Mathematics of Science Coll. Tianjin Univ. Tianjin 300072 P. R. China Tianjin Foreign Studies Univ. Tianjin 300204 P. R. China Inst. of Optoelectronics Shenzhen Univ. Shenzhen 518060 P. R. China National Lab of Precision Measurement Technology and Instrumentation Tianjin 300072 P. R. China

Aiming at the shortcomings of the existing wedgelet compression arithmetics, a novel contour-representing algorithm based on wedgelets is presented in this paper. Firstly the input image is binarized and the most optimized wedgelets are found by means of quadtree framework. Then the contours are reconstructed by applying the wedgelets, the data volume is compressed, and the shortcomings of the contour representation based on normal wavelet are ameliorated, the better effect for the visualization is obtained, too.

关键词： wedgelet binarization quadtree.

NUMErICAL MODELING OF KELVIN-HELMHOLTZ INSTABILITY AND rAYLEIGH-TAYLOr INSTABILITY AT LArGE DEFOrMATION STAGE——(Ⅰ) NUMErICAL METHOD AND NUMErICAL rESULTS OF rAYLEIGHTAYLOr INSTABILITY

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Journal of Hydrodynamics 1991年第1期3卷 37-44页

作者： Zhang Hui-sheng, Department of Applied Mechanics, Fudan University, Shanghai 200433, P. r. China Fudan Univ Shanghai China

This paper improves the discrete vortex method for modeling Kelvin-Helmholtz instability and rayleigh-Tay- lor instability by proper choice of velocity weighted average coefficients, redistribution of markers and successive adding of computational points with the increase of interfacial deformation and gives the numerical results of rayleigh-Taylor instability. The numerical results show that the first two techniques greatly enhance the ability of the discrete vortex method for modeling large interracial deformations and the last technique greatly reduces the computational amounts of the numerical modeling at large deformation stage. The numerical modeling of rayleigh- Taylor instability not only reproduces some phenomena such as the roll up at the end part of the spike observed in experiments but also finds some new phenomena such as the splashes at the roll up parts which needs to be tested by experiment.

关键词： mode NUMErICAL MODELING OF KELVIN-HELMHOLTZ INSTABILITY AND rAYLEIGH-TAYLOr INSTABILITY AT LArGE DEFOrMATION STAGE NUMErICAL METHOD AND NUMErICAL rESULTS OF rAYLEIGHTAYLOr INSTABILITY AT

BASIC FLOW PATTErNS AND OPTIMUM HYDrAULIC DESIGN OF A SUCTION BOX OF PUMPING STATION

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Journal of Hydrodynamics 2000年第4期12卷 46-51页

作者： Lu Lin guang Yangzhou University, Yangzhou 225009, P.r.China (received April 14, 2000) Yangzhou Univ. Yangzhou 225009 China

A numerical method based on 3 D turbulence flow was applied to simulate the flow pattern in suction boxes of six different types. In light of the computational results, the basic flow patterns in the boxes were revealed and a theoretical method to optimize hydraulically design of the suction box is developed. The box geometrical parameters, which influence the flow pattern in the box, could be optimized. The optimum criteria for the hydraulic design of the suction boxes of six types established, respectively. Furthermore, a summarization is given here based on the classification of the basic flow patterns in order to systematically understand the hydraulic design of suction boxes.

关键词： flow pattern optimum design suction box pumping station

Effects of LIDAr DEM resolution in hydrodynamic modelling: model sensitivity for cross-sections

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International Journal of Digital Earth 2013年第1期6卷 3-27页

作者： M.Podhorányi J.Unucka P.Bobál V.ríhová Institute of geoinformatics faculty of mining and geologyvsb-technical university of ostravaostravaczech republic Institute of geological engineering faculty of mining and geology of vsb-technical universityostravaczech republic

With the development of science and technology the entire Earth,together with all of its phenomena,is gradually becoming an object of computer *** several years,this process has also affected water components,which are essential for the development of humans and economies on ***,monitoring of its resources and movement across the Earth’s surface is the main object of investigation of several research *** recent years,hydraulic modelling has experienced significant development that meets water and computer connection *** study consequently dealt with hydraulic modelling and uncertainties in the data that may affect the resulting flood *** analysed the effect of cross-sections generated and the subsequent inundation areas in Digital Elevation Models of different *** basic DEM was constructed from data obtained by the LIDAr *** results were obtained using a one-dimensional(1-D)model,HEC-rAS,and its extension,*** Olsˇe and Stona´vka river junction,located in the northeast region of the Czech republic,was selected for *** resolutions selected for the study to generate cross-sections and the subsequent inundation areas were 1 m,5 m and 10 *** resulting cross-sections were confronted with the actual surveyed cross-sections.

关键词： digital flood cross-sections LIDAr hydrodynamic model HEC-rAS river topography

Prediction of spatial soil loss impacted by long-term land-use/land-cover change in a tropical watershed

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Geoscience Frontiers 2019年第2期10卷 389-403页

作者： J.H.Abdulkareem B.Pradhan W.N.A.Sulaiman N.r.Jamil Department of Environmental Science Faculty of Environmental StudiesUniversiti Putra Malaysia (UPM) Department of Soil Science Institute for Agricultural Research/Faculty of AgricultureAhmadu Bello University Department of Civil Engineering Faculty of EngineeringGeospatial Information Science Research Center (GISRC)Universiti Putra Malaysia (UPM) Centre for Advanced Modeling and Geospatial Information Systems (CAMGIS) Faculty of Engineering and Information TechnologyUniversity of Technology Sydney Department of Energy and Mineral resources Engineering Choongmu-gwanSejong University

The devastating effect of soil erosion is one of the major sources of land degradation that affects human lives in many ways which occur mainly due to deforestation, poor agricultural practices, overgrazing,wildfire and urbanization. Soil erosion often leads to soil truncation, loss of fertility, slope instability, *** causes irreversible effects on the poorly renewable soil resource. In view of this, a study was conducted in Kelantan river basin to predict soil loss as influenced by long-term land use/land-cover(LULC) changes in the area. The study was conducted with the aim of predicting and assessing soil erosion as it is influenced by long-term LULC changes. The 13,100 km^2 watershed was delineated into four sub-catchments Galas, Pergau, Lebir and Nenggiri for precise result estimation and ease of execution. GIS-based Universal Soil Loss Equation(USLE) model was used to predict soil loss in this study. The model inputs used for the temporal and spatial calculation of soil erosion include rainfall erosivity factor,topographic factor, land cover and management factor as well as erodibility factor. The results showed that 67.54% of soil loss is located under low erosion potential(reversible soil loss) or 0-1 t ha^(-1) yr^(-1) soil loss in Galas, 59.17% in Pergau, 53.32% in Lebir and 56.76% in Nenggiri all under the 2013 LULC *** from the correlation of soil erosion rates with LULC changes indicated that cleared land in all the four catchments and under all LULC conditions(1984-2013) appears to be the dominant with the highest erosion losses. Similarly, grassland and forest were also observed to regulate erosion rates in the area. This is because the vegetation cover provided by these LULC types protects the soil from direct impact of rain drops which invariably reduce soil loss to the barest minimum. Overall, it was concluded that the results have shown the significance of LULC in the control of erosion. Maps generated from the study may be usef

关键词： Soil erosion USLE Landuse/cover changes GIS Malaysia

Electrochemical synthesis of nanosized iron oxide-alumina system

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Journal of Advanced Ceramics 2016年第1期5卷 70-76页

作者： A.F.DrESVYANNIKOV I.O.GrIGOrYEVA L.r.KHAYrULLINA E.V.PETrOVA Kazan National research Technological University(KNrTU) Kazan 420015 Russia

An electrochemical method for the synthesis of complex dispersed oxide system Al2O3-Fe2O3, based on the combined aluminum and iron anodic dissolution in aqueous solution containing chloride ions, has been suggested. The phase composition and morphology of Al2O3-Fe2O3 dispersed precipitate have been investigated by means of X-ray fluorescence, X-ray diffraction (XrD), and scanning electron microscopy (SEM). The influence of the electrolysis mode on the characteristics of the synthesized oxide system has been shown. It is found that the direct current (DC) mode allows us to adjust the phase correlation in the precipitate and to obtain a particle size which is two or more times smaller than the particle size of the samples synthesized by means of the alternating current (AC).

关键词： alumina iron oxide mixed oxide system electrochemical synthesis nanoparticles