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Ru/NimnB spherical cluster pillar for highly proficient green hydrogen electrocatalyst at high current density

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Journal of Energy Chemistry 2025年第1期100卷 397-408页

作者： md Ahasan Habib Shusen Lin mehedi Hasan Joni Sumiya Akter Dristy Rutuja mandavkar Jae-Hun Jeong Jihoon Lee Department of Electronic Engineering College of Electronics and Information Kwangwoon University

Advanced OER/HER electrocatalytic alternatives are crucial for the wide adaptation of green hydrogen ***,Ru/NimnB spherical cluster pillar （SCP）,denoted as Ru/NimnB,is synthesized using a combination of electro-deposition and hydrothermal *** investigation of Ru doping in the NimnB matrix revealed significant improvements in electrocatalytic *** Ru/NimnB SCPs demonstrate superior OER/HER activity with low overpotentials of 150 and 103 mV at 50mA/cm2in 1 m KOH,making them highly competitive with state-of-the-art ***,the Ru/NimnB SCPs exhibit a low 2-E cell voltage of 2.80 V at ultra-high current density of 2,000 m A/cm2in 1 m KOH,outperforming the standard benchmark electrodes of RuO2||Pt/C,thereby positioning Ru/NimnB as one of the best bifunctional *** SCPs exhibit exceptional high-current characteristics,stability and corrosion resistance,as evidenced by continuous operation at 1,000 mA/cm2high-current density for over 150 h in 6 m KOH at elevated temperatures under harsh industrial *** a small amount of Ru incorporation significantly enhances the electrocatalytic performances of NimnB,attributed to increased active sites and improved intrinsic properties such as conductivity,adsorption/desorption capability and reaction ***,Ru/NimnB SCPs present a promising bi-functional electrode concept for efficient green H2production.

关键词： Advanced electrocatalyst High current Corrosion resistance Industrial requirement

Phase analysis of AlFe2B2 by synchrotron X-ray diffraction,magnetic and m?ssbauer studies

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Progress in Natural Science:materials International 2017年第2期27卷 251-256页

作者： tahir Ali m.N.Khan E.Ahmed Asad Ali Physics Division Pakistan Institute of Nuclear Science and technology Department of Physics Abdul Wali Khan University PINSAT Preston University

The structural and magnetic properties of essentially phase pure AlFe2B2prepared by arc melting were compared with a sample containing impurities. Analysis was carried out by means of synchrotron X-ray diffraction, magnetic measurements and m?ssbauer spectroscopy. The analysis of synchrotron X-ray diffraction data confirmed the orthorhombic structure of space group Cmmm for AlFe2B2with Al13Fe4as main impurity phase. The magnetic measurements revealed an unsaturated ferromagnetic state in AlFe2B2with a transition temperature（Tc） of 286 K. Isothermal magnetization measurment at 5 K gave a saturation magnetization of 0.7 μB per Fe atom while Arrott plots establish the second order nature of ferromagnetic transition. The thermal evolution of m?ssbauer spectra confirmed the ferromagnetic nature of this material revealing an hyperfine field of 73 kOe and an isomer shift of 0.46 mm/s at 100 K. The m?ssbauer spectra of a phase pure sample was compared with the one containing impurity phases. It is suggested that the low temperature paramagnetic contribution in m?ssbauer spectra of phase pure material may have its origin in some intrinsic phenomena arising from defects or inhomogeneities in crystal structure.

关键词： AlFe2B2 Synchrotron X-ray diffraction Ferromagnetism mossbauer effect spectroscopy

Symmetry solutions of a nonlinear elastic wave equation with third-order anharmonic corrections

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Applied mathematics and mechanics(English Edition) 2009年第8期30卷 1017-1026页

作者： m.tahir mustafa Khalid masood Department of mathematics and Statistics King Fahd University of Petroleum and MineralsDhahran 31261 Saudi Arabia Department of mathematics Hafr Al-Batin Community College King Fahd University of Petroleum and MineralsP. O. Box 5087 Dhahran 31261 Saudi Arabia

Lie symmetry method is applied to analyze a nonlinear elastic wave equation for longitudinal deformations with third-order anharmonic corrections to the elastic energy. Symmetry algebra is found and reductions to second-order ordinary differential equations （ODEs） are obtained through invariance under different symmetries. The reduced ODEs are further analyzed to obtain several exact solutions in an explicit form. It was observed in the literature that anharmonic corrections generally lead to solutions with time-dependent singularities in finite times singularities, we also obtain solutions which Along with solutions with time-dependent do not exhibit time-dependent singularities.

关键词： group invariant solutions Lie symmetries nonlinear elasticity equations partial differential equations

Petrogenesis of Granites from the Utla Area of Gadoon, North-West Pakistan: Implications from Petrography and Geochemistry

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Journal of Earth Science 2014年第3期25卷 445-459页

作者： muhammad Sajid mohammad Arif m tahir Shah Department of Geology University of Peshawar National Center of Excellence in Geology University of Peshawar

The granitic rocks around the Utla area（Gadoon）, north western, Pakistan are studied in terms of their petrographic features and geochemical characteristics. Although predominantly mega-porphyritic, some of the Utla granites are massive and display fine-grained equi-granular texture. Some of the mega-porphyritic varieties exhibit foliation and seem to be restricted to shear zones. In addition to being distributed largely as phenocrysts, all the essential minerals（plagioclase, perthitic alkali feldspar and quartz） also constitute the groundmass. The studied samples also contain minor to accessory amounts of tourmaline, muscovite and biotite and accessory to trace amounts of apatite, andalusite, garnet, zircon, monazite, epidote and sphene. A detailed geochemical investigation reveals a calc-alkaline and peraluminous character of the Utla granites. The peraluminous character and total lack of hornblende designate their S-type character while a volcanic arc or syn-collisional tectonic setting for their emplacement is indicated by discrimination diagrams. Further examination shows that the melt parental to the Utla granite was derived from a plagioclase-poor, clay-rich rock, i.e., pelite. The petrogenetically significant petrographic and geochemical features of the Utla granite show greater similarity with the mansehra than the Ambela granites. These include（i） the predominantly megaporphyritic texture,（ii） the presence of andalusite and tourmaline,（iii） the calc-alkaline geochemical signature and（iv） an indication of similar melt source rock character.

关键词： petrography geochemistry granite Utla Pakistan.

Astrocyte in prion disease: a double-edged sword

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Neural Regeneration Research 2022年第8期17卷 1659-1665页

作者： Waqas tahir Simrika Thapa Hermann m.Schatzl Department of Comparative Biology&Experimental medicine Faculty of Veterinary MedicineUniversity of CalgaryCalgaryABCanada Calgary Prion Research Unit University of CalgaryCalgaryABCanada Hotchkiss Brain Institute University of CalgaryCalgaryABCanada

Prion diseases are infectious protein misfolding disorders of the central nervous system that result from misfolding of the cellular prion protein(PrPC)into the pathologic isoform *** hallmarks of prion disease are depositions of pathological prion protein PrPSc,neuronal loss,spongiform degeneration and astrogliosis in the *** diseases affect human and animals,there is no effective therapy,and they invariably remain *** a long time,neuronal loss was considered the sole reason for neurodegeneration in prion pathogenesis,and the contribution of non-neuronal cells like microglia and astrocytes was considered less *** evidence suggests that neurodegeneration during prion pathogenesis is a consequence of a complex interplay between neuronal and non-neuronal cells in the brain,but the exact role of these non-neuronal cells during prion pathology is still *** are non-neuronal cells that regulate brain homeostasis under physiological ***,astrocytes can deposit PrPSc aggregates and propagate prions in prion-infected ***,sub-populations of reactive astrocytes that include neurotrophic and neurotoxic species have been identified,differentially expressed in the brain during prion *** the exact role of astrocytes in prion disease is hampered by the lack of in vitro models of prion-infected ***,we established a murine astrocyte cell line persistently infected with mouse-adapted prions,and showed how such astrocytes differentially process various prion *** the complexity of the role of astrocytes in prion pathogenesis,we need more in vitro and in vivo models for exploring the contribution of sub-populations of reactive astrocytes,their differential regulation of signaling cascades,and the interaction with neurons and microglia during prion *** will help to establish novel in vivo models and define new therapeutic targets against prion

关键词： Alzheimer’s disease astrocytes central nervous system Creutzfeldt-Jakob disease glial cells neurodegeneration prion prion disease prion protein scrapie

Characterization of ion irradiated silicon surfaces ablated by laser-induced breakdown spectroscopy

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Chinese Physics B 2018年第8期27卷 505-510页

作者： T Iqbal m Abrar m B tahir m Seemab A majid S Rafique Department of Physics Faculty of Sciences University of Gujrat Hafiz Hayat Campus Department of Physics Hazara University Mansehra Department of Physics University of Engineering and Technology (UET)Lahore Pakistan

Low energy metallic ions, generated by a Q-switched Nd：YAG laser （1064-nm wavelength, 10-mJ energy, 9-nm 12-ns-pulse width, 1011 W/cm2 intensity） irradiated on a silicon substrate to modify various properties, such as electrical, morphological, and structural modifications. Thomson parabola technique is used to calculate the energy of these metallic ions whereas the electrical conductivity is calculated with the help of Four-point probe. Interestingly circular tracks forming chain like damage trails are produced via these energetic ions which are carefully examined by optical microscopy. It is observed that excitation, ionization, and cascade collisions are responsible for surface modifications of irradiated samples. Four-point probe analysis revealed that the electrical conductivity of substrate has reduced with increasing trend of atomic number of irradiated metallic ions （A1, Ti, Cu, and Au）. The x-ray diffraction analysis elucidated the crystallographic changes leading to reduction of grain size of N-type silicon substrate, which is also associated with the metallic ions used. The decreasing trend of conductivity and grain size is due to thermal stresses, scattering effect, structural imperfections, and non-uniform conduction of energy absorbed by substrate atoms after the ion irradiation.

关键词： ablation Thomson parabola technique four-point probe

A broadband cross-polarization conversion anisotropic metasurface based on multiple plasmon resonances

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Chinese Physics B 2018年第1期27卷 357-364页

作者： m Ismail Khan Farooq A tahir Research Institute for microwave and millimeter-wave Studies (RImmS) National University of Sciences and Technology (NUST) Department of Electrical Engineering COMSATS Institute of Information Technology Attock Campus

A compact broadband cross-polarization conversion metasurface functioning in the microwave regime is realized and experimentally demonstrated. The metasurface consists of a two-dimensional periodic arrangement of anisotropic double- slit split-ring-resonator-based unit cells printed on top of a dielectric substrate, backed by metallic cladding. The proposed metasurface converts an x- or y-polarized wave into its orthogonal polarization over a fractional bandwidth of 100% from 5- 15 GHz, both for normal as well as oblique incidence. moreover, the sub-wavelength unit-cell size, thin dielectric substrate, and unique unit-cell design collectively make the response of the metasurface same for both polarizations and insensitive to the incidence angle. The designed structure is fabricated and tested. The measurement and simulation results are found to be consistent with each other.

关键词： cross-polarization conversion anisotropy metasurface plasmon resonances

GIS based ArcPRZm-3 model for bentazon leaching towards groundwater

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Journal of Environmental Sciences 2010年第12期22卷 1854-1859页

作者： tahir Ali Akbar Henry Lin College of Natural Resources University of Wisconsin-Stevens Point Department of Civil Engineering Schulich School of EngineeringUniversity of Calgary2500 University Drive NWCalgaryAlbertaT2N 1N4Canada Department of Crop and Soil Sciences The Pennsylvania State UniversityUniversity ParkPA 16802USA

Groundwater contamination due to pesticide applications on agricultural lands is of great environmental concern. The mathematical models help to understand the mechanism of pesticide leaching in soils towards groundwater. We developed a user-friendly model called ArcPRZm-3 by integrating widely used Pesticide Root Zone model version 3 （PRZm-3） using Visual Basic and Geographic Information System （GIS） based Avenue programming. ArcPRZm-3 could be used to simulate pesticide leaching towards groundwater with user-friendly input interfaces coupled with databases of crops, soils and pesticides. The outputs from ArcPRZm-3 could be visualized in user-friendly formats of tables, charts and maps. In this study we evaluated ArcPRZm-3 model by simulating bentazon leaching in soil towards groundwater. ArcPRZm-3 was applied to 37 sites in Woodruff County, Arkansas, USA to observe the daily average dissolved bentazon concentration for soybean, sorghum and rice at a depth of 1.8 m for a period of two years. Nineteen ranks of bentazon leaching potential were obtained using ArcPRZm-3 for all sites having different soil and crop combinations. ArcPRZm-3 simulation results for bentazon were compatible with the field monitored data in term of relative ranking and trend, although some uncertainties exist. This study indicated that macropore flow mechanism would be important in analyzing the effect of irrigation on groundwater contamination due to pesticides. Overall, ArcPRZm-3 could be used to simulate pesticide leaching towards groundwater more efficiently and effectively as compared to PRZm-3.

关键词： ArcPRZm-3 PRZm-3 GIS pesticide leaching groundwater contamination bentazon

mechanical and thermodynamical stability of BiVO4 polymorphs using first-principles study

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Chinese Physics B 2017年第3期26卷 395-403页

作者： A K m Farid UI Islam md Nurul Huda Liton H m Tariqul Islam md Al Helal md Kamruzzaman Department of Computer Science and Engineering Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Chemistry Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics and materials Science and Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong Hong Kong SAR China

First principles calculations of structural, electronic, mechanical, and thermodynamic properties of different poly- morphs of BiVO4 are performed using Bender-type plane/wave ultrasoft pseudopotentials within the generalized gradient approximation （GGA） in the flame of density functional theory （DFT）. The calculated structural and electronic properties are consistent with the previous theoretical and experimental results. The electronic structures reveal that m-BiVO4, op- BiVO4, and st-BiVO4 have indirect band gaps, on the other hand, zt-BiVO4 has a direct band gap. From the DOS and mulliken＇s charge analysis, it is observed that only m-BiVO4 has 6s2 Bi lone pair. Bond population analysis indicates that st-BiVO4 shows a more ionic nature and a similar result is obtained from the elastic properties. From the elastic prop- erties, it is observed that st-BiVO4 is more mechanically stable than the others, st-BiVO4 is more ductile and useful for high electro-optical and electro-mechanical coupling devices. Our calculated thermodynamic properties confirm the similar characteristics found from electronic and elastic properties, m-BiVO4 is useful as photocatalysts, solid state electrolyte, and electrode and other polymorphs are applicable in electronic device fabrications.

关键词： BiVO4 crystal structure lone pair mechanical stability