检索结果-南通市图书馆

Influence of Cu doping in Magnesium Hydroxide Nanoparticles for Bandgap Engineering

在线全文

学校读者我要写书评

暂无评论

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

Large scale silver nanowires network fabricated by MeV hydrogen (H＋) ion beam irradiation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2016年第4期25卷 268-273页

作者： Honey s naseem.s Ishaq A Maaza M Bhatti M T Wan D Center of Excellence in solid state Physics University of the Punjab Lahore Pakistan National Center for Physics Quaid-i-Azam University Islamabad 44000 Pakistan UNEsCO-UNIsA Africa Chair in Nanosciences/Nanotechnology College of Graduate Studies University of South Africa Muckleneuk ridge P. O. Box 392 Pretoria South Africa Nanosciences African Network (NANOAFNET) iThemba LABS National Research Foundation Old Faure road P. O. Box 722 Somerset West 7129 South Africa Department of Physics Bahauddin Zakariya University Multan 60800 Pakistan school of Materials science and Engineering Shanghai University Shanghai 201900 China

A random two-dimensional large scale nano-network of silver nanowires （Ag-NWs） is fabricated by MeV hydrogen （H＋） ion beam irradiation. Ag-NWs are irradiated under H＋ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H＋ ion beam-induced welding of Ag-NWs at intersecting positions. H＋ ion beam induced welding is confirmed by transmission electron microscopy （TEM） and scanning electron microscopy （sEM）. Moreover, the structure of Ag NWs remains stable under H＋ ion beam, and networks are optically transparent. Morphology also remains stable under H＋ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H＋ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps： ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices.

关键词： Ag nanowires H+ ion irradiation nanowelding large scale nano-network optical properties

structural,electronic,and magnetic properties of Co-doped ZnO

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2012年第9期21卷 414-421页

作者： Bakhtiar Ul Haq A. Afaq R. Ahmed s. naseem Center of Excellence in solid state Physics University of the Punjab Quid-e-Azam CampusLahore-54590 Pakistan Department of Physics Faculty of Science Universiti Teknologi Malaysia Skudai Johar Malaysia Center of Excellence in solid state Physics University of the Punjab Quid-e-Azam Campus Lahore-54590 Pakistan

Density functional theory based calculations have been carried out to study structural, electronic, and magnetic properties of Znl-xCoxO （x = 0, 0.25, 0.50, 0.75） in the zinc-blende phase, and the generalized gradient approximation proposed by Wu and Cohen has been used. Our calculated lattice constants decrease while the bulk moduli increase with the increase of Co2＋ concentration. The calculated spin polarized band structures show the metallic behavior of Co-doped ZnO for both the up and the down spin cases with various doping concentrations. Moreover, the electron population is found to shift from the Zn-O bond to the Co-O bond with the increase of Co2~ concentration. The total magnetic moment~ the interstitial magnetic moment, the valence and the conduction band edge spin splitting energies, and the exchange constants decrease, while the local magnetic moments of Zn, Co, O, the exchange spin splitting energies, and crystal field splitting energies increase with the increase of dopant concentration.

关键词： density functional theory magnetic semiconductors generalized gradient approximation

Effect of Cu/Zn substitution in MgO Nanostructures for Tuning the Optical Bandgap and structural Properties

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials science) 2022年第6期37卷 1035-1040页

作者： ATIF Dawar s naseem.shah M AsIF siddiqui YAsMEEN Bibi Department of Physics Federal Urdu University of ArtsScience and TechnologyKarachiPakistan Department of Chemistry Federal Urdu University of ArtsScience and TechnologyKarachiPakistan

Low cost co-precipitation method was used to synthesize Cu(0-0.05)doped MgO samples with fixed concertation of Zn=0.01.X-ray diffraction(XRD)spectra confirmed the phase purity of the samples for 0≤Cu≤0.03 doping *** secondary phase for 0.04≤Cu≤0.05 exhibited the formation of mixed metal *** crystallite size was found to increase from 17.5 to 23.5 nm for 0≤Cu≤0.03 and then decreased from 22 to 18.5 nm for 0.04≤Cu≤*** estimated bandgap first reduced from 5.48 to 4.88 eV and then increased from 5.21 to 5.36 *** morphology of the samples transformed from spheroidal shape to star-like *** obtained results reveal that the structural and optical property are in good agreement with the morphological *** peak shifting towards the lower values of vibrational frequency from 694 to 579 cm^(-1) confirms the incorporation of Cu/Zn in Mg-O *** tuning of optical bandgap and structural properties with varying dopant concentration in MgO nanomaterials can be used for multifunctional modern energy storage and optoelectronic devices.

关键词： Cu/Zn doping MgO optical bandgap morphology vibrational modes

Face Labelings of Klein-bottle Fullerenes

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

学校读者我要写书评

暂无评论

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

structural and dielectric study of nano-crystalline single phase sn1-xNixs(XNi=0-10%) showing room temperature ferromagnetism

在线全文

学校读者我要写书评

暂无评论

Progress in Natural science:Materials International 2017年第3期27卷 303-310页

作者： B.Parveen M.Hassan s.Atiq s.Riaz s.naseem M.Asif Toseef Materials Growth and simulation Laboratory Department of PhysicsUniversity of the Punjab Centre of Excellence in solid state Physics University of the Punjab Department of Physics Govt. Islamia College

sns is a promising Ⅳ-Ⅵ semiconductor,which is very less explored for diluted magnetic semiconducting and dielectric *** this study,the Ni doping(xNi=0-10mol%) effects on sns host lattice were investigated.A simple and low cost co-precipitation technique was employed to grow Ni doped sns *** X-ray diffraction confirmed single phase orthorhombic structure with a nano-crystalline nature that was further verified through the surface structure observed by scanning electron *** edge x-ray absorption fine structure spectroscopy revealed a shift in the Ni absorption edge towards higher energy,depicting the formation of Ni+3oxidation *** impedance measurements,in the frequency range 1 kHz to 20 MHz,depict that owing to the excellent sensitivity to the electromagnetic radiations at the low energy,the Ni doped sns finds potential applications in various energy related *** sample magnetometer measurements have elucidated room temperature ferromagnetism,which depicts potential memory device applications.

关键词： Diluted magnetic semiconductors Room temperature ferromagnetism Near edge x-ray absorption fine structure spectroscopy Dielectric properties Co-precipitation method

Preparation and characterization of doubly substituted microwave absorbing material by sol-gel technique for super high frequency applications

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural science:Materials International 2018年第4期28卷 478-482页

作者： Imran sadiq shahzad naseem.saira Riaz s.sajjad Hussain Muhammad Naeem Ashiq Mazhar Rana Centre of Excellence in solid state Physics University of the Punjab Institute of Chemical sciences Bahauddin Zakariya University

Rare earth Dy;and divalent Mn;elements substituting W-type hexagonal ferrites Ba;Dy;Zn;Fe;Mn;O;（x=0,0.02,0.06,0.1 and y=0,0.1,0.3,0.5）were prepared by sol-gel *** thermo-gravimetric analysis（TGA）and differential scanning calorimetry（DsC）was carried out to find the temperature at which single phase can be *** patterns indicate the presence of the single phase for all the synthesized samples with the absence of any extra peak due to unreacted material and secondary *** occurrence of absorption bands at low wave numbers(563 and 446 cm;),can be assigned to the stretching vibration of metal and oxygen ions in FTIR spectra,which also confirms the single hexagonal phase for prepared *** grains are of platelet like structure,which enhances the microwave absorption properties of hexagonal *** synthesized material exhibits the minimum reflection loss of-20.9 dB at 11.8 GHz frequency,which reflects the applications of this material in super high frequency *** microwave conductivity of the material increases with frequency.

关键词： sol-Gel synthesis XRD Microwave absorption properties Microwave conductivity

Image Fusion Using Wavelet Transformation and XGboost Algorithm

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第4期79卷 801-817页

作者： shahid naseem Tariq Mahmood Amjad Rehman Khan Umer Farooq samra Nawazish Faten s.Alamri Tanzila saba Department of Information sciences Division of S&TUniversity of EducationLahore54770Pakistan Artificial Intelligence and Data Analytics(AIDA)Lab CCIS Prince Sultan UniversityRiyadh11586Saudi Arabia Faculty of Information sciences University of EducationVehari CampusVehari61100Pakistan Department of Computer science University of Engineering and TechnologyTaxila47050Pakistan Department of Mathematical sciences College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia

Recently,there have been several uses for digital image *** fusion has become a prominent application in the domain of imaging *** create one final image that provesmore informative and helpful compared to the original input images,image fusion merges two or more initial images of the same *** fusion aims to produce,enhance,and transform significant elements of the source images into combined images for the sake of human visual *** fusion is commonly employed for feature extraction in smart robots,clinical imaging,audiovisual camera integration,manufacturing process monitoring,electronic circuit design,advanced device diagnostics,and intelligent assembly line robots,with image quality varying depending on *** research paper presents various methods for merging images in spatial and frequency domains,including a blend of stable and curvelet transformations,everageMax-Min,weighted principal component analysis(PCA),HIs(Hue,Intensity,saturation),wavelet transform,discrete cosine transform(DCT),dual-tree Complex Wavelet Transform(CWT),and multiple wavelet *** fusion methods integrate data from several source images of an identical target,thereby enhancing information in an extremely efficient *** precisely,in imaging techniques,the depth of field constraint precludes images from focusing on every object,leading to the exclusion of certain *** tackle thess challanges,a very efficient multi-focus wavelet decomposition and recompositionmethod is *** use of these wavelet decomposition and recomposition techniques enables this method to make use of existing optimized wavelet code and filter *** simulated outcomes provide evidence that the suggested approach initially extracts particular characteristics from images in order to accurately reflect the level of clarity portrayed in the original *** study enhances the performance of the eXtreme Gradient Boosting(XGBoos

关键词： Image fusion max-min average CWT XGBoost DCT inclusive innovations spatial and frequency domain