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Large-scale frequent testing and tracing to supplement control of Covid-19 and vaccination rollout constrained by supply

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Infectious Disease Modelling 2021年第1期6卷 955-974页

作者： Lia Humphrey Edward W.Thommes Roie Fields Laurent Coudeville naseem hakim Ayman Chit Jianhong Wu Monica G.Cojocaru Department of Mathematics and Statistics University of GuelphGuelphOntarioCanada Vaccine Epidemiology and Modeling Sanofi PasteurCanada Founder ***Canada Sanofi Pasteur&Leslie Dan School of Pharmacy University of TorontoCanada Department of Mathematics and Statistics York UniversityCanada

Non-pharmaceutical interventions(NPI)were implemented all around the world in the fight against COVID-19:Social distancing,shelter-in-place,mask wearing,*** mitigate transmission,together with testing and contact-tracing to identify,isolate and treat the *** majority of countries have relied on the former measures,followed by a ramping up of their testing and tracing *** present here the cases of South Korea,Italy,Canada and the United States,as a look back to lessons that can be drawn for controlling the pandemic,specifically through the means of testing and *** fitting a disease transmission model to daily case report data in each of the four countries,we first show that their combination of social-distancing and testing/tracing have had a significant impact on the evolution of their first wave of pandemic *** then consider the hypothetical scenario where the only NPI measures implemented past the first pandemic wave consisted of isolating individuals due to repeated,country-scale testing and contact tracing,as a mean of lifting social distancing measures without a resurgence of *** give estimates on the average isolation rates needed to occur in each *** find that testing and tracing each individual of a country,on average,every 4.5 days(South Korea),5.7 days(Canada),6 days(Italy)and 3.5 days(US),would have been sufficient to mitigate their second pandemic *** also considered the situation in Canada to see how a frequent large-scale asymptomatic testing and contact tracing could have been used in combination with vaccination rollout to reduce the infection in the *** could offer an alternative approach towards preventing and controlling an outbreak when vaccine supply is limited,while testing capacity has been increasingly enhanced.

关键词： Pandemic modelling Pandemic evolution scenarios Testing frequency policy modelling

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Preparation and Properties of Evaporated CdTe and All Thin Film CdTe/CdS Solar Cells

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Chinese Physics Letters 1991年第5期8卷 255-258页

作者： Shahzad naseem Centre for Solid State Physics University of the PunjabQuaid-e-Azam CampusLahore(PAKISTAN)

Cadmium telluride thin films were prepared by vacuum evaporation of CdTe powder in an attempt to fabricate all thin film solar cells of the type CdTe/*** of CdTe has shown it to have a band gap of 1.522eV and a resistivity of 22Ω-*** prepared,solar cells exhibited low values of output *** quantity of copper was then deposited on top of the CdTe/CdS solar cells and the whole system was annealed at 350℃.This copper doping changed the output parameters favorably with a maximum efficiency of 1.9%.

关键词： CdTe/CdS CdTe copper

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Effect of Reaction Temperature and Time on the Structural Properties of Cu(In,Ga)Se_2 Thin Films Deposited by Sequential Elemental Layer Technique

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Journal of Materials Science & Technology 2007年第4期23卷 499-503页

作者： Saira RIAZ Shahzad naseem Centre for Solid State Physics University of the Punjab QACLahore-54590Pakistan

Thin films of copper indium gallium selenide Cu（In,Ga）Se2 （CIGS） were prepared by sequential elemental layer deposition in vacuum at room temperature. The as-deposited films were heated in vacuum for compound formation, and were studied at temperature as high as 1250℃ for the first time. These films were concurrently studied for their structural properties by X-ray diffraction （XRD） technique. The XRD analyses include phase transition studies, grain size variation and microstrain measurements with the reaction temperature and *** has been observed that there are three distinct regions of variation in all these parameters. These regions belong to three temperature regimes：〈450℃, 450-950℃, and 〉950℃. It is also seen that the compound formation starts at 250℃, with ternary phases appearing at 350℃ or above. Whereas, there is another phase shift at 950℃ without any preference to the quaternary compound.

关键词： Cu(In,Ga)Se2 (CIGS) X-ray Diffraction Thin films Structural analysis

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Face Labelings of Klein-bottle Fullerenes

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Acta Mathematicae Applicatae Sinica 2017年第2期33卷 277-286页

作者： Martin BACA Maria naseem Ayesha SHABBIR Department of Appl. Mathematics and Informatics Technical University Kosice Slovakia Abdus Salam School of Mathematical Sciences GC University 68-B New Muslim Town Lahore Pakistan University College of Engineering Sciences and Technology Lahore Leads University Lahore Pakistan

The Klein-bottle fullerene is a finite trivalent graph embedded on the Klein-bottle such that each face is a hexagon. The paper deals with the problem of labeling the vertices, edges and faces of the Klein-bottle fullerene in such a way that the label of a face and the labels of the vertices and edges surrounding that face add up to a weight of that face and the weights of all 6-sided faces constitute an arithmetic progression of difference d. In this paper we study the existence of such labelings for several differences d.

关键词： Klein-bottle fullerene d-antimagic labeling super d-antimagic labeling

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Biogeochemical evaluation of Nannorrhops ritchiana: A Mg-flora from Khuzdar, Balochistan, Pakistan

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Chinese Journal Of Geochemistry 2005年第4期24卷 327-337页

作者： Sadaf naseem Shahid naseem Erum Bashir Khaula Shirin Shamim A. Sheikh Department of Geology University of Karachi Karachi 75270 PakistanDepartment of Geology University of Karachi Karachi 75270 PakistanDepartment of Geology University of Karachi Karachi 75270 PakistanPCSIR Laboratories Complex off University Road Karachi PakistanDepartment of Geology University of Karachi Karachi 75270 Pakistan

Nannorrhops ritchiana (Mazari Palm) is a distinctive flora growing in the Saharo-Sindian region. It is well distributed on the ultramafic soil, derived from the Bela Ophiolite in the Khuzdar District, Balochistan, Pakistan. Quantitative estimation of Ca, Mg, Fe and Ni in soil and plant ash has been carried out. The constituents of plant ash have been discussed in relation to soil chemistry, pH, climate, mobility, average abundance in plant ash and exclusion mechanism of the flora. Relationship among Ca, Mg, Fe and Ni has been established using scattergrams to evaluate the biogeochemistry of the plant. High contents of Mg and high coefficient of biological absorption allow it to be classed as Mg-flora. Both Ca and Fe appeared to be antagonistic to Mg. The metal assemblage of N. ritchiana nicely reflected the nature of the bed rock as being serpentinized ultramafic, and its corresponding soils. Good exclusion mechanism of N. ritchiana did not allow it to absorb high Ni from the soil. Relatively high concentrations of Ni in N. ritchiana from the Baran Lak area can be used to localize Ni-mineralization in the study area.; Statistical analyses, such as minimum, maximum, mean, mode, median, standard deviations, and coefficient of correlation, were also made to improve raw geochemical data and interpretations.

关键词：巴基斯坦生物化学超碱土壤土壤化学

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Surface Passivation of Ti/4H-SiC Schottky Barrier Diode

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Communications in Theoretical Physics 2012年第10期58卷 577-582页

作者： Muhammad Khalid Saira Riaz Shahzad naseem Microelectronics Division/Centre of Excellence in Solid State Physics School of Physical SciencesUniversity of the Punjab

Surface properties of SiC power devices mostly depend on the passivation layer(PL).This layer has direct influence on electrical characteristics of devices.2D numerical simulation of forward and reverse characteristics with and without different(PLs)(SiO2,HfO2 and Si3N4) has been *** results show that the breakdown voltage increases with increasing PL thickness,and there is a lesser significant effect on forward *** maximum breakdown voltage with and without SiO2 PL is 1240 V and 276 V,***2 PL has compatibility with SiC surface providing high breakdown voltage,6 and 8% higher than that of HfO2 and Si3N4 *** leakage current is observed which then further decreases on reducing the thickness of ***,variation of forward current with dielectric constant and thickness of PLs was ***,it is suggested that matches of our results with published experimental results indicate that the Sentaurus TCAD simulator is a predictive tool for the SiC Schottky barrier diode simulation.

关键词： Passivation breakdown voltage leakage current electric field on-resistance

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Evaporated Thin Films of CdS and CdTe: Optimization for Photovoltaic Applications

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Journal of Materials Science & Technology 1996年第2期12卷 89-94页

作者： Shahzad naseem Dilawaiz Nazir Riffat Mumtaz Khadim Hussain Centre for Solid State Physics University of the PunjabQuaid-e-Azam CampusLahore-54590Pakistan

Thin films of cadmium sulphide and cadmium telluride have been prepared by thermal evaporation under various conditions of deposition. These films have been characterized optically. electrically and for structure determination. The results of these characterizations along with the initial results of all thin film CdS/CdTe solar cells are presented in this paper

关键词： Evaporated Thin Films of CdS and CdTe Thin Optimization for Photovoltaic Applications CdS

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Hydrogeochemistry of the Winder River and adjoining tributaries, Balochistan, Pakistan

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Chinese Journal Of Geochemistry 2007年第3期26卷 259-266页

作者： Erum Bashir Shahid naseem Salma Hamza Department of Geology University of Karachi Pakistan Federal Urdu University of Arts Science and Technology Karachi Pakistan

Quantitative estimation of ground and stream waters draining through sedimentary rocks of the Pab and Mor ranges (Jurassic-Cretaceous) and the Bela ophiolite has been made. The degree of correspondence among cations and anions has been estimated in order to evaluate their mutual relationships. The abundance of major ions is interpreted to be related to bedrocks and climatic conditions, which may contribute to the genetic affiliation. The log TDS and Na/Na+Ca ratio reflected supremacy of weathering of rocks with some influence of evaporation. Ionic relationship is exhibited in the form of Stiff diagrams. Patterns of ionic composition revealed high NaCl, medium Ca(HCO3)2 and low MgSO4. Piper diagram has been used to classify the hydrofacies. The important hydrogeochemical parameters have been estimated for assessment of groundwater quality for domestic purposes in accordance to WHO. Irrigation water qualities have been evaluated in terms of EC, SAR, RSC, ESP and pH.

关键词：水文地球化学水质量变体巴基斯坦

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PREPARATION OF THERMALLY EVAPORATED CdTe THIN FILMS

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Chinese Physics Letters 1990年第11期7卷 510-513页

作者： Shahzad naseem Naseer-ud-Din Khadim Hussain Centre for Solid State Physics University of the PunjabQuaidCampusLahorePakistan

Thin films of cadmium telluride were prepared by evaporating cadmium telluride powder in a vacuum of less than 10^(-4) *** substrate temperature was varied systematically from room temperature to 300℃.The results of optical and structural characterizations have revealed that the films posses a high value of absorption coefficient with a bandgap value m the range 1.475-1.769eV,and that the films are of cubic structure with a preferred orientation along(111)*** probe measurements have shown that resistivity of these films is affected by the change in substrate temperature,with the lowest value(12.6 Ω·cm)being at 200℃.

关键词： films value cadmium

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Influence of Cu doping in Magnesium Hydroxide Nanoparticles for Bandgap Engineering

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Journal of Wuhan University of Technology(Materials Science) 2023年第3期38卷 485-489页

作者： SYED Masood Raza S naseem Shah ADEEL Tahir YASMEEN Bibi Department of Physics Federal Urdu University of ArtsScience&TechnologyKarachiPakistan Department of Chemistry Federal Urdu University of ArtsScience&TechnologyKarachiPakistan

Cu doped Mg(OH)_(2) nanoparticles were synthesized with varying concentrations from 0 to 10%by a chemical synthesis technique of coprecipitation.X-rays diffraction (XRD) of the samples confirms that all the samples acquire the hexagonal crystal *** results indicated the solubility limit of dopant in the host material and the secondary phase of CuO was observed beyond 3%Cu doping in Mg(OH)_(2).The reduction in the size of nanoparticles was observed from 166 to 103 nm for Mg(OH)_(2) and 10% Cu doped Mg(OH)_(2)samples,*** shift in absorption spectra exhibited the systematical enhancement in optical bandgap from 5.25 to 6.085 eV.A good correlation was observed between the bandgap energy and crystallite size of the nanocrystals which confirmed the size induced effect in the *** transformation in the sample morphology was observed from irregular spherical particles to sepals like shapes with increasing the Cu concentration in the host *** energy dispersive X-Ray (EDX) analysis confirmed the purity of mass percentage composition of the elements present in the samples.

关键词： Cu doped Mg(OH)_(2) nanoparticles phase purity optical band gap morphologies

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