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Teflon-pad shaping process of circular metal blanks into quasi-cup specimens by theoretical and experimental methods

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Transactions of Nonferrous Metals Society of China 2016年第1期26卷 213-227页

作者： abbas NIKNEJAD Iman KARAMI FATH Mechanical Engineering Department Yasouj University

Teflon-pad shaping process of circular metal blanks into quasi-cup specimens is investigated by theoretical and experimental methods in the quasi-static condition. In the experiments, circular metal sheets are formed into the quasi-cup samples by compressing them between a Teflon-filled die and a rigid punch with desirable shape. To investigate influences of different parameters on the forming progress, 12 rigid punches with different dimensions, two blank material types of aluminum and galvanized iron, three blank thicknesses of 0.6, 1.1 and 1.5 mm, and two Teflon-fillers of PVC and polyurethane are used in several experimental tests. In the analytical part, theoretical deformation models of metal blank and Teflon-filler are introduced and based on energy method, energy absorptions by the blank and Teflon-filler are calculated to derive a theoretical formula for predicting total required energy of the forming process. For this purpose, several energy absorption mechanisms are considered in the blank and filler. Furthermore, predictions by theoretical equation are compared with the corresponding experimental tests to study the verity of the calculated formulas. Theoretical and experimental results illustrate change trend of forming energy with respect to blank thickness. Also, the performed forming tests show that when external cone angle of rigid punch with respect to the horizontal direction increases, forming energy increases nonlinearly; and when the depth of spherical part of rigid punch increases, the probability of rupture increases. Additionally, the experiments demonstrate that there is a direct relationship between the forming energy and flow stress of the blanks. Furthermore, experimental observations illustrate that forming energy of a certain blank with PVC Teflon-filler is higher than that of a similar specimen with polyurethane Teflon-filler; but, the probability of wrinkling decreases when PVC Teflon-pad is used as the filler; and it is advantage of

关键词： Teflon-pad forming circular metal blank quasi-cup specimen PVC Teflon-filler polyurethane Teflon-filler forming energy

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Numerical study of homogeneous–heterogeneous reactions on stagnation point flow of ferrofluid with non-linear slip condition

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Chinese Journal of Chemical Engineering 2017年第1期25卷 11-17页

作者： Zaheer abbas Mariam Sheikh Department of Mathematics The Islamia University of Bahalwalpur Bahawalpur 63100 Pakistan

This study deals with the stagnation point flow of ferrofluid over a flat plate with non-linear slip boundary condition in the presence of homogeneous-heterogeneous *** kinds of ferroparticles,namely,magnetite(Fe_3O_4),cobalt ferrite(CoFe_2O_4) and manganese zinc ferrite(Mn-ZnFe_2O_4) are taken into account with water and kerosene as conventional base *** developed model of homogeneous-heterogeneous reactions in boundary layer flow with equal and unequal diffusivities for reactant and autocatalysis is *** governing partial differential equations are converted into system of non-linear ordinary differential equations by mean of similarity *** ordinary differential equations are integrated numerically using shooting *** effects of pertinent parameters on velocity and concentration profiles are presented graphically and *** found that in the presence of Fe_3O_4-kerosene and CoFe_2O_4-kerosene,velocity profiles increase for large values of α and β whereas there is a decrement in concentration profiles with increasing values of if and K_***,the comparison between non-magnetic(A1_2O_3) and magnetic Fe_3O_4 nanoparticles is given in tabular form.

关键词： Ferrofluid Stagnation point flow Homogeneous-heterogeneous reactions Generalized slip boundary condition Numerical solution

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Is Ziarat a Potential Site for Conventional or Unconventional Energy Resources?

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1544-1557页

作者： Sarfraz KHAN Umair Bin NISAR khawar A.AHMED Muhammad WASEEM Waqas AHMED National Centre of Excellence in Geology University of PeshawarPeshawar25130Pakistan Comsats Institute of Information and Technology AbbottabadPakistan Comsats Institute of Information and Technology IslamabadPakistan

A structural interpretation of the Ziarat block in the Balochistan region （a part of the Suleiman Fold and Thrust Belt） has been carried out using seismic and seismological data. Seismic data consists of nine 2.5D pre-stack migrated seismic lines, whereas the seismological data covers the Fault Plane Solution and source parameters. Structural interpretation describes two broad fault sets of fore and back thrusts in the study area that have resulted in the development of pop-up structures, accountable for the structural traps and seismicity pattern in terms of seismic hazard. Seismic interpretation includes time and depth contour maps of the Dungan Formation and Ranikot group, while seismological interpretation includes Fault Plane Solution, that is correlated with a geological and structural map of the area for the interpretation of the nature of the subsurface faults. Principal stresses are also estimated for the Ranikot group and Dungan Formation. In order to calculate anisotropic elastic properties, the parameters of the rock strength of the formations are first determined from seismic data, along with the dominant stresses （vertical, minimum horizontal, and maximum horizontal）. The differential ratio of the maximum and minimum horizontal stresses is obtained to indicate optimal zones for hydraulic fracturing, and to assess the potential for geothermal energy reservoir prospect generation. The stress maps indicate high values towards the deeper part of the horizon, and low towards the shallower part, attributed to the lithological and structural variation in the area. Outcomes of structural interpretation indicate a good correlation of structure and tectonics from both seismological and seismic methods.

关键词： fault plane solution reservoir monitoring stress analysis hydraulic fracturing geothermal energy structural interpretation

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Modeling relationships between the network distance and travel time dynamics for assessing equity of accessibility to urban parks

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Geo-Spatial Information Science 2021年第3期24卷 509-526页

作者： Tahereh Ghaemi Rad abbas Alimohammadi GIS Department Faculty of Geomatics EngineeringCenter of Excellence in Geospatial Information TechnologyK.N.Toosi University of TechnologyTehranIran

Static models of accessibility are usually based on the fixed distance or Average Travel Time(ATT)*** of ignoring the traffic as a dynamic process affecting the accessibility through the change of Travel Time(TT),these models lead to unperceived temporal *** contrast to the consideration of the temporal Variation of TT(VTT)in the previous studies,the variation of traffic-related TT and its relations with network distance has not been *** this study,relations between VTT and network distance to access urban parks in Tehran megacity has been *** maps at five times of day are used to produce TT maps of Traffic Analysis Zones(TAZs)to their 3-closest *** of the Gini coefficients of accessibility show significant inequities of accessibility at different times of *** between the distance,ATT,and TT_(max) are modeled by statistical *** show both TT and TTmax have significant positive relations with distance and traffic and reach their maximum at 6 *** of significant relations between distance,ATT,TT_(max),and VTT provides interesting knowledge for the conversion of temporal measures of equity(TT)to a physical measure of equity(distance).A simple application of these findings for effective management of the spatiotemporal inequities is the definition of critical distances from public *** an example,to decrease the TT_(max) of TAZs to less than 12 min,their maximum distance to the closest parks should be less than 4 *** developed approach can be adopted for the accessibility evaluation of the other public services,particularly the health and education centers.

关键词： Spatiotemporal equity accessibility travel time variability Gini coefficient Lorenz curve urban parks Tehran megacity

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Formal Modeling of Self-Adaptive Resource Scheduling in Cloud

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Computers, Materials & Continua 2023年第1期74卷 1183-1197页

作者： Atif Ishaq Khan Syed Asad Raza kazmi Awais Qasim Department of Computer Science Government College UniversityLahore54000Pakistan

A self-adaptive resource provisioning on demand is a critical factor in cloud *** selection of accurate amount of resources at run time is not easy due to dynamic nature of ***,a self-adaptive strategy of resources is required to deal with dynamic nature of requests based on run time change in *** this paper we proposed a Cloud-based Adaptive Resource Scheduling Strategy(CARSS)Framework that formally addresses these issues and is more expressive than traditional *** decision making in CARSS is based on more than one ***-K based framework determines the state of the resources based on their current ***-Arc Petri Net(TAPN)is used to model system formally and behaviour is expressed in TCTL,while TAPAAL model checker verifies the underline properties of the system.

关键词： Formal modeling multi-agent self-adaptive cloud computing

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Analysis of socio-environmental impacts of the loss of urban trees and vegetation in Lahore,Pakistan:a review of public perception

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Ecological Processes 2016年第1期5卷 48-59页

作者： Safdar Ali Shirazi Jamil H.kazmi Department of Geography University of the PunjabQuaid-i-Azam CampusLahorePakistan Department of Geography University of KarachiKarachiPakistan

Introduction:This paper focused on the process of urbanization in Lahore and its correlation with the loss of urban vegetation and perceived environmental impacts based on local population’s perception through administration of a questionnaire *** is known as a city of gardens and green spaces in Pakistan and always possessed rich green character in its long *** the past few decades due to rapid urbanization,the city has lost its aesthetically important urban vegetation,tress,and *** field studies and remote sensing data revealed that the loss of vegetation has been experienced at an astonishing rate in many union councils of the ***:This study was conceived to probe importance and value of the urban tress and vegetation of Lahore in an environmental context and its general importance for the residents of the *** objectives were to analyze the role of vegetation in the life of citizens;the specific objective was to reveal the attitudes and responses of city dwellers about loss of urban trees/vegetation and its role in the overall environment,process of urbanization,and maintenance *** the present paper,perception of local people(n=2080)regarding the socio-environmental impacts due to the ongoing process of urbanization and detriments of vegetation loss has been probed through administration of a household *** collected data has been tested with respondent’s age,gender,marital status,education,monthly income,and ***:This study was an attempt to document and explore the change in historical transformation in vegetation and perception of the sample population of *** perception survey has revealed that urbanization is the major cause of loss of vegetation and has caused a number of perceived environmental problems in the ***:The study underlined an analysis of people’s perceptions regarding the loss of trees and *** perceived socio-environmental findings revea

关键词： Anthropogenic Union council Socio-environmental Perception Vegetation Urban trees

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Multifaceted roles of extracellular RNAs in different diseases

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Military Medical Research 2023年第3期10卷 359-368页

作者： Abdullah Muhammad Sohail Muhammad Babar khawar Ali Afzal Ali Hassan Sara Shahzaman Ahmed Ali Molecular Medicine and Cancer Therapeutics Lab Department of ZoologyFaculty of SciencesUniversity of Central PunjabLahorePakistan Applied Molecular Biology and Biomedicine Lab Department of ZoologyUniversity of NarowalNarowalPakistan

Extracellular RNAs(exRNAs) are novel circulating factors that can be used as biomarkers in various diseases. Their unique and diverse kinds, as well as their role as biomarkers, make them significant biomarkers. There has been immense work carried out since the discovery of exRNAs in circulation and other biological fluids to catalog and determine whether exRNAs may be utilized as indicators for health and illness. In this review, we aim to understand the current state of exRNAs in relation to various diseases and their potential as biomarkers. We will also review current issues and challenges faced in using exRNAs, with clinical and lab trials, that can be used as viable markers for different diseases.

关键词： Extracellular RNAs(exRNAs) Extracellular vehicles(EVs) Cancer Biomarkers Exosomes

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Efficacy of extract from Ononis spinosa *** ethanol-induced gastric ulcer in rats

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Journal of Traditional Chinese Medicine 2021年第2期41卷 270-275页

作者： Manal Ahmad abbas Yasser Ibrahim Kandil Manal Mohammad abbas Faculty of Allied Medical Sciences Al-Ahliyya Amman UniversityAmman 19328Jordan Biochemistry Department Faculty of PharmacyAl-Azhar UniversityCairo 11884Egypt

OBJECTIVE:To investigate the efficacy of the extract from Ononis spinosa L.(***)on ethanol-induced gastric ulcer in ***:Phytochemical constituents of the extract from *** were analyzed using liquid chromatography-mass *** were classified into 4 equal groups;ulcer control received oral vehicle;positive control was administered with 40 mg/kg esomeprazole(standard drug)and 2 groups received 0.5 and 1 g/kg of *** extract,*** ulcer was induced by absolute ethanol(5 mL/kg)orally to all *** of ulcer index,cyclooxygenase-2(COX-2)expression and determination of total glutathione level in gastric mucosa were ***:Oral administration of the extract from *** at doses 0.5 and 1 g/kg lowered the ulcer indices by 80.39%and 98.71%,respectively,compared to 67.89%by esomeprazole(40 mg/kg).Histologically,treatment with the extract decreased necrosis and hemorrhage in mucosa and edema and infiltration by inflammatory cells in *** immunohistochemical technique,it was demonstrated that COX-2 expression increased in mucosa of animals treated with the extract as well as by *** and esomeprazole increased total glutathione level in the stomach compared to *** was the major compound of the extract followed by trifolirhizin,myricitrin,gentisic acid,cycloartenol and ***:The present study demonstrated that the extract from *** was able to protect gastric mucosa from ethanol injury by at least 2 mechanisms,namely the induction of COX-2 and decreasing oxidative stress in the stomach.

关键词： Ononis Stomach ulcer Cyclooxygenase 2 Ethanol Ulcer index

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First investigation of eclipsing binary KIC 9026766:analysis of light curve and periodic changes

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Research in Astronomy and Astrophysics 2021年第11期21卷 55-61页

作者： Somaye Soomandar abbas Abedi Faculty of Sciences University of BirjandIran

We investigate a short-period W UMa binary KIC 9026766 with an orbital period of 0.2721278 d in the Kepler field of *** applying an automated q-search for the folded light curve and producing a synthetic light curve for this object based on the PHOEBE code,we calculate the fundamental stellar *** also analyze the O-C curve of the primary *** orbital period changes can be attributed to the combination of an upward quadratic function and light-travel time effect(LTTE)due to a possible third body with a minimum mass of 0.029 M☉and an orbital period of 972.5866±0.0041 *** relative luminosity of the primary and secondary eclipses(MinⅠ-MinⅡ)is *** periodogram of the residuals of the LTTE and MinⅠ-MinⅡshow peaks with the same period of 0.8566 *** background effect of two nearby stars on our target is the possible reason for this *** considering the amplitudes and periods of the remaining signals in the O-C curve of minima,spot motion is possible.

关键词： techniques:photometric stars:individual:KIC 9026766

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Phantom Accretion onto the Schwarzschild de-Sitter Black Hole

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Chinese Physics Letters 2011年第9期28卷 34-37页

作者： M Sharif G abbas Department of Mathematics University of the PunjabQuaid-e-Azam CampusLahore-54590Pakistan

We deal with phantom energy accretion onto the Schwarzschild de-Sitter black *** energy flux conservation,relativistic Bernoulli equation and mass flux conservation equation are formulated to discuss the phantom *** discuss the conditions for critical *** is found that the mass of the black hole decreases due to phantom *** exist two critical points which lie in the exterior of horizons(black hole and cosmological horizons).The results for the phantom energy accretion onto the Schwarzschild black hole can be recovered by takingΛ→0.

关键词： accretion horizon black

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