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Studying the patterns of alien and native floras of some habitats in Srinagar city, Kashmir, India

Ecological Processes 2015年第1期4卷 17-28页

作者： syed Mubashir Andrabi Zafar ahmad Reshi Manzoor ahmad Shah Salman Qureshi Department of Botany University of KashmirSrinagar 190006Jammu and KashmirIndia Department of Geography Humboldt University of BerlinRudower Chaussee 1612489 BerlinGermany School of architecture Birmingham City UniversityThe Parkside Building5 Cardigan StreetBirmingham B47BDUK

Introduction:Urban flora is an important component of human-dominated ecosystems that links urban dwellers with *** study aims at compiling and analysing the alien and native vascular plant species of some selected habitats in the Srinagar city,Kashmir,***:Bi-seasonal sampling was employed and each habitat type(viz.,graveyards,grasslands,orchards and wastelands)was sampled at seven different ***:The number of species recorded from graveyards was 96;from grasslands 112;141 from orchards and 110 from *** level of invasion among habitats varied from 67.27%to 68.75%,with a mean value of 67.86%;out of clubbed species list,64.84%were ***,Poaceae,Brassicaceae and Fabaceae were the biggest families in all four habitat ***:Our research shows that across habitats,alien plant species are the predominant part of their floras.

关键词： Alien Flora Herbs Srinagar city Level of invasion

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Highly active electrocatalysis of hydrogen evolution reaction in alkaline medium by ni–P alloy: A capacitance-activity relationship

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Journal of Energy Chemistry 2017年第6期26卷 1245-1251页

作者： Chao Cheng syed Shoaib ahmad Shah Tayyaba Najam Ling Zhang Xueqiang Qi Zidong Wei The State Key Laboratory of Power Transmission Equipment & System Security and New Technology and College of Chemistry and Chemical Engineering Chongqing University College of Chemistry and Chemical Engineering Chongqing University of Technology

Different weights of amorphous ni–P alloy with same P contents were electrodeposited on nickel plate with same area used as cathode for hydrogen evolution reaction(HER). The amorphous ni–P alloy coatings were characterized for their surface morphology and composition through Scanning electron microscopy(SEM) and Energy dispersive X-ray spectroscopy(EDS) techniques, X-ray photoelectron spectroscopy(XPS) and X-ray diffraction(XRD) analysis. The electrocatalytic activity for HER in alkaline medium is determined by linear scan voltammetry(LSV) and a relationship between HER activity and capacitance is established. The capacitance varies with the loading of the ni–P on ni plate but the activity for HER is directly proportional to the capacitance in alkaline and vice versa. 3#ni–P/ni containing 3.85 mg ni–P alloy with highest capacitance performs the best catalytic activity. This work provides direct evidence to explore the capacitance influence on the electrocatalystic activity for the HER.

关键词： HER ni–P alloy Capacitance Electrodeposition

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Formation mechanisms of ni-Al intermetallics during heat treatment of ni coating on 6061 Al substrate

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Transactions of Nonferrous Metals Society of China 2015年第12期25卷 3959-3966页

作者： Mohsen ADABI ahmad Ali AMADEH School of Metallurgy and Materials Engineering College of Engineering University of Tehran Department of Metallurgy and Materials Engineering Faculty of EngineeringRoudehen Branch Islamic Azad University

The formation mechanisms and growth kinetics of Al3 ni and Al3ni2 in ni-Al diffusion couple prepared by electrodeposition of ni on Al substrate were investigated. The nickel coating with 20 μm thickness was applied on 6061 aluminum alloy by direct current electroplating. The samples were then heat-treated for different durations at 450, 500 and 550 °C under argon atmosphere. The intermetallic phases were identified by means of scanning electron microscopy（SEM）, energy dispersive spectrometry（EDS） and X-ray diffraction（XRD）. The results showed that the formation of intermetallic phases consisted of two important steps. The first step was the lateral growth of intermetallic phase from separate sites, resulting in the formation of a continuous layer. The second step was the growth of the continuous intermetallic layer in the direction perpendicular to the interface. However, excessive increase in thickness of intermetallic phases led to the detachment of reaction products, i.e., Al3 ni and Al3ni2, from the substrate. It was also observed that aluminum was the dominant diffusing element during Al3 ni growth, while nickel diffusion was dominant during Al3ni2 growth. The growth kinetics of both Al3 ni and Al3ni2 phases obeyed a parabolic law.

关键词： ni-Al intermetallics electrodeposition heat treatment formation mechanism growth kinetics

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The charge state distribution of B, C, Si, ni, Cu and Au ions on 5 MV pelletron accelerator

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Nuclear Science and Techniques 2017年第5期28卷 43-47页

作者： Ali Awais Javaid Hussain Muhammad Usman Waheed Akram Kashif Shahzad Turab Ali Ishaq ahmad Malik Maaza Experimental Physics Laboratories National Centre for Physics Islamabad 44000 Pakistan UNESCO-UniSA Africa Chair in Nanosciences/ Nanotechnology College of Graduate Studies University of South Africa Muckleneuk Ridge PO Box 392 PretoriaSouth Africa Nanosciences African Network (NANOAFNET) iThemba LABS-National Research Foundation 1 Old Faure RoadPO Box 722 Somerset West Western Cape Province 7129South Africa

Stripper gas and terminal potential play a key role for the charge state distribution in a tandem pelletron accelerator. The knowledge of this distribution is important for experiments performed on tandem accelerators. The charge state distribution of B, C, Si, ni, Cu and Au beams is measured by using ar as stripper gas, and terminal potential is varied from 0.3 to 3.0 MV on 5UDH-2 tandem pelletron accelerator installed at the National Centre for Physics, Islamabad. The individual charge state is measured after the switching magnet at 15° in high-energy portion. It is observed that the higher charge states are stable in the range of lower and middle atomic masses of periodic table, whereas higher atomic mass(Au) shows beam current instability in higher charge states. For carbon,the charge distribution at 1.7 MV terminal potential by varying stripper gas pressure is also studied, which resulted in decreased overall transmission with good current value for higher charge states.

关键词： Pelletron accelerator Charge state distribution Stripper gas Terminal potential

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Petrography, Geochemistry and Petrogensis of Basal Flow from ar-Rabba area, Central Jordan

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International Journal of Geosciences 2016年第3期7卷 378-396页

作者： Ibrahim ahmad Ali Bany Yaseen Institute of Earth and Environmental Sciences Water Environment and Arid Regions Research CentreAl al-Bayt University Mafraq Jordan

Thirty basaltic rock samples collected from a central Jordan at ar-Rabba area were studied. The samples cover about 20 km2 from the Al-Rabba basalt flow. The Al-Rabba Basalt (RB) introduced Miocene to Pleistocene period. Petrography, Geochemistry and Petrogenesis investigations were carried out for the RB. The petrography analyses of the RB rocks are composed of plagioclase, pyroxene, olivine, opaque minerals (magnetite), and including secondary minerals calcite, iddingsite, and clay. The RB rocks have low range of major and trace elements concentrations, and under sodic alkaline magma series. The geochemical analysis data of RB indicated that RB was derived from a slightly fractionation magma as reflected by high MgO concentration range between (5.4 to 11.7 wt%), and Mg number from 42 to 63.8, and high concentration Cr (18 - 385 ppm), ni (160 - 364 ppm) and low silica content ( 41.79 - 49.87 wt%). The chemical classification of RB is divided into basaltic, calc-alkaline to alkali basalt. The tectonic setting of RB is explained by using discrimination diagrams, Ti-Zr-Y, Ti-Zr-Sr and MgO-FeO(tot)-Al2O3, the RB plotted within the plate, calc-alkali and continental basalt respectively. The Rayleigh fractionation equation modeled for Sr and Ba vector diagram indicated the RB had fractionation for clinopyroxene, orthpyro-xene, olivine and trace of plagioclase.

关键词： Calc-Alkaline Basalt Fractionation Tectonic Setting ar-Rabba Jordan

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