检索结果-南通市图书馆

Impact of marshy area reclamation by various vegetations on soil-nematode community structure in Dachigam National Park

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Soil Ecology Letters 2023年第3期5卷 123-133页

作者： Humira Nesar shahid afzal Zarrin Imran Wasim Ahmad Nematode Biodiversity Research Lab Department of ZoologyAligarh Muslim UniversityAligarh 202002India

Marshy areas are ecologically important and sensitive areas which are under immense pressure,such as reclamation by various terrestrial ***,how these vegetation types disrupt the stability of nematode community is *** present study determined how the soil nematode community responded to shifting environmental states by using nematode abundances,nematode indices and metabolic footprints as *** this context,we selected three types of reclaimed vegetation around a marshy land(MR)in Dachigam National Park,Kashmir,which includes grassland(GL),forest(FR)and cropland(CL)to investigate the soil nematode ***,Plectus,Eudorylaimus,and Aphelenchus proved more sensitive to reclamation *** revealed decrease in total nematode and bacterivore *** reduced diversity in CL,whereas no effect was observed in the GL and FR as compared to *** index indicated shift from fungal decomposition to bacterial decomposition pathway in *** nematode faunal profile depicted grassland(GL)as the most structured ecosystem compared to MR,FR,and *** results suggest that vegetation type regulates the structure,function,and stability of the soil food web,which has significant implications for managing the vegetation cover in a sustainable manner in the Dachigam National Park.

关键词： nematodes diversity vegetation habitat reclamation

Ion-acoustic waves with non-planar wavefronts

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第1期26卷 1-7页

作者： Shujaht BUKHARI Muhammad shahid Ata-ur RAHMAN Department of Physics The University of Azad Jummu and KashmirMuzaffarabad 13100Azad Kashmir Department of Physics Women University of Azad Jammu&KashmirBagh 12500Pakistan Department of Physics Islamia College PeshawerPeshawar 25120Pakistan

The ion-acoustic(IA) mode exhibiting various orbital angular momentum(OAM) states is examined in a plasma with drifting *** constituent plasma species are modeled with a non-gyrotropic Maxwellian distribution and discussion of dispersion relation and growth rate of twisted IA waves under various conditions is *** the domain of kinetic model,the twisted IA waves are characterized by Laguerre-Gaussian(LG) solutions,where plasma distribution function and electric field are decomposed into axial and azimuthal *** plasma response function is obtained under paraxial approximations and investigated for threshold condition of instability growth rate with helical electric field *** impact of an extra electron specie on the instability is demonstrated through a comparison of twisted waves for single and double electron species.

关键词： instability twist parameter wave excitation orbital angular momentum threshold limit

Gravity-driven powder flow and the influence of external vibration on flow characteristics

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第5期88卷 201-209页

作者： Muhammad shahid Ansari Ratna Kumar Annabattula Sathyan Subbiah Department of Mechanical Engineering Indian Institute of Technology MadrasChennai 600036India

The controlled and homogeneous flow of dry granular powders through hoppers is essential for applications,namely,packaging of food grains,fertilizers and additive manufacturing processes such as directed energy deposition for better product *** of the major issues encountered in the granular flows through hoppers is flow stagnation due to the well-known arching ***-assisted granular flow through hoppers is one of the mechanisms used for better mass flow *** this work,the influence of external mechanical vibration on the powder flow is investigated experimentally and using discrete element ***,the mass flow rate through the hopper increases with an increase in vibration amplitude and then decreases,signifying the existence of an optimal amplitude of *** DEM simulations explained the underlying mechanisms for the existence of an optimal amplitude of vibration corresponding to the maximum mass flow rate.A range of vibration amplitudes from 0 mm to 3.5 mm is used to study the flow behaviour;the maximum flow of around 33 g/s to 35 g/s is observed for 0.75 mm to 1.25 mm vibration amplitude for the hopper-particle combination studied in this *** work also reports the influence of vibration frequency,hopper,and particle dimension on the flow *** research facilitates the effective use of mechanical vibration to enhance powder flow that can further be extended to non-spherical and multi-material particles.

关键词： Discrete element method Flow rate Granular flow Path tracking Vibration intensity

Consequences of Rényi entropy on the thermal geometries and Hawking evaporation of topological dyonic dilaton black hole

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第2期76卷 102-110页

作者： Muhammad Yasir Xia Tiecheng Muhammad Usman shahid Chaudhary Department of Mathematics Shanghai University and Newtouch Center for Mathematics of Shanghai UniversityShanghai200444China Department of Natural Sciences and Humanities University of Engineering and Technology LahoreNew CampusPakistan

The thermodynamics of black holes(BHs)has had a profound impact on theoretical physics,providing insight into the nature of gravity,the quantum structure of spacetime and the fundamental laws governing the *** this study,we investigate thermal geometries and Hawking evaporation of the recently proposed topological dyonic dilaton BH in anti-de Sitter(Ad S)*** consider Rényi entropy and obtain the relations for pressure,heat capacity and Gibbs free energy and observe that the Rényi parameter and dilaton field play a vital role in the phase transition and stability of the ***,we use Weinhold,Ruppeiner and Hendi Panahiyah Eslam Momennia models to evaluate the scalar curvature of the BH and find out that the divergence points of the scalar curvature coincides with the zero of specific ***,using Stefan–Boltzmann law,we determine that the BH without a dilaton field evaporates far more quickly compared to the dilaton BH in Ad S space.

关键词： topological dyonic dilaton black hole phase transition thermal geometry Hawking evaporation

Experimental Study on Heat Storage Properties Comparison of Paraffin/Metal Foams Phase Change Material Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第2期33卷 469-478页

作者： Waqar AHMED Abid HUSSAIN Hanzla shahid Imran ALI Hafiz Muhammad ALI Department of Mechanical Engineering University of Engineering and TechnologyTaxila47080Pakistan Department of Mechanical Engineering Institute of Space TechnologyIslamabadPakistan Department of Mechanical Mechatronics and Manufacturing EngineeringUniversity of Engineering and Technology LahoreFaisalabad CampusPunjabPakistan Mechanical Engineering Department King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Renewable Energy and Power Systems(IRC-REPS) King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia

Heat storage properties of phase change materials(PCMs) are essential characteristics that perform a key role in thermal heat energy storage *** thermal properties of PCMs can be improved by developing metal foam/PCM *** addition of metal foam in PCMs has a significant effect on the thermal characteristics of *** this paper,the heat storage properties of two different metal foam/PCM composites were experimentally *** behavior of paraffin in metal foam(copper and iron-nickel)/paraffin composites concerning pure paraffin at a constant heat flux of 1000 W/m^(2) in three directions simultaneously(x,y,and z) was *** was infiltrated into copper and iron-nickel foams to develop composite materials which resulted in enhancing the thermal conductivity of the paraffin.A comparative analysis is made on the heat storage properties of paraffin in copper and iron-nickel foams/paraffin *** temperature distribution during the phase transition process is experimentally *** comparison indicates that temperature uniformity in copper foam/paraffin composite is better than in iron-nickel foam/paraffin composite and pure paraffin at the same heat *** results show that at heat flux of 1000 W/m^(2),the heat storage time for copper foam/paraffin composite is 20.63% of that of iron-nickel foam/paraffin composite.

关键词： heat storage capacity paraffin/metal foam composite temperature uniformity heat storage rate phase transition process

Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture

在线全文

学校读者我要写书评

暂无评论

Acta Geochimica 2024年第2期43卷 214-234页

作者： Maria Kaleem Erum Bashir shahid Naseem Tahir Rafique Bushra Shahab Department of Geology University of KarachiKarachi 75270Pakistan Applied Chemistry Research Centre PCSIR Laboratories ComplexKarachi 75280Pakistan

This study is theﬁrst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical *** outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the ***-ﬁve soil samples were collected,mainly from the arable land of the Porali *** drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric ***-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial *** granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt *** indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of *** indices reﬂect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr *** of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the *** correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type *** may result in the undesirable accumulation of certain trace elements which adversely affects crops.

关键词： Weathering indices Pollution indices Accumulation Repercussions Trace elements Multivariate analyses Porali Plain Balochistan

Structural performance of flexible freeform panelssubjected to wind loads

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第6期18卷 851-869页

作者： Yong YOO Zaryab shahid Renzhe CHEN Maria KOLIOU Anastasia MULIANA Negar KALANTAR Zachry Department of Civil and Environmental Engineering Texas A&M UniversityCollege StationTX 77843USA J.Mike Walker'66 Department of Mechanical Engineering Texas A&M UniversityCollege StationTX 77843USA Architecture Division California College of the ArtsSan FranciscoCA 94107USA

An increased number of hurricanes and tornadoes have been recorded worldwide in the last decade,while research efforts to reduce wind-related damage to structures become *** architecture,which focuses on generating complex curved shapes including streamlined shapes,has recently gained *** study focuses on investigating the potential of kerf panels,which have unique flexibility depending on the cut patterns and densities,to generate complex shapes for facades and their performance under wind *** investigate the kerf panel's potential capacity against wind loads,static and dynamic analyses were conducted for two kerf panel types with different cut densities and pre-deformed *** was observed that although solid panels result in smaller displacement amplitudes,stresses,and strains in some cases,the kerf panels allow for global and local cell deformations resulting in stress reduction in various locations with the potential to reduce damage due to overstress in *** the predeformed kerf panels,it was observed that both the overall stress and strain responses in kerf cut arrangements were lower than those of the flat-shaped *** study shows the promise of the use of kerf panels in achieving both design flexibility and performance demands when exposed to service *** that this newly proposed architectural configuration(design paradigm)for facades could revolutionize structural engineering by pushing complex freeform shapes to a standard practice that intertwines aesthetic arguments,building performance requirements,and material design considerations has the potential for significant practical applications.

关键词： freeform structure kerfing method wind load analysis cladding component

Rational manipulation of electrolyte to induce homogeneous SEI on hard carbon anode for sodium-ion battery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第7期94卷 414-429页

作者： Lu Liu Lingling Xiao Zhi Sun shahid Bashir Ramesh Kasi Yonghong Gu Ramesh Subramaniam Research Center for Clean Utilization Technology Phosphorous Resources Hubei Three Gorges PolytechnicYichang 443000HubeiChina Department of Physics Faculty of ScienceUniversiti MalayaKuala Lumpur 50603Malaysia UM Power Energy Dedicated Advanced Centre(UMPEDAC) Level 4Wisma R&DUniversiti MalayaKuala Lumpur 59990Malaysia Department of Chemistry Saveetha School of EngineeringInstitute of Medical and Technical ScienceSaveetha UniversityChennai 602105TamilnaduIndia

Sodium-ion batteries (SIBs) have great potential to be the next major energy storage devices due to their obvious advantages and developing advanced electrodes and electrolytes is urgently necessary to promote its future ***,hard carbon as a state-of-the-art anode of SIBs still suffers from the low initial Coulomb efficiency and unsatisfactory rate capability,which could be improved by forming desirable solid electrolyte interphases (SEI) to some ***,the chemistry and morphology of these interfacial layers are fundamental parameters affecting the overall battery operation,and optimizing the electrolyte to dictate the quality of SEI on hard carbon is a key ***,this review summarizes the recent research on SEI design by electrolyte manipulation from solvents,salts,and *** also presents some potential mechanisms of SEI formation in various electrolyte ***,the current advanced characterization techniques for electrolyte and SEI structure analyses have been comprehensively ***,current challenges and future perspectives of SEI formation on hard carbon anode for SIBs are provided from the viewpoints of its compositions,evolution processes,structures,and characterization techniques,which will promote SEI efficient manipulation and improve the performance of hard carbon,and further contribute to the development of SIBs.

关键词： SEI Electrolyte optimization Hard carbon Electrochemical performance Sodium-ion batteries

Outage Analysis of Optimal UAV Cooperation with IRS via Energy Harvesting Enhancement Assisted Computational Offloading

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第2期138卷 1885-1905页

作者： Baofeng Ji Ying Wang Weixing Wang shahid Mumtaz Charalampos Tsimenidis School of Information Engineering Henan University of Science and TechnologyLuoyang471000China Research and Innovation Center of Intelligent System Longmen LaboratoryLuoyang471000China State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System(CEMEE) Luoyang471000China Sustainable Digital Communications and Energy Systems(DIGCOM)Group Nottingham Trent UniversityNottinghamUK

The utilization of mobile edge computing(MEC)for unmanned aerial vehicle(UAV)communication presents a viable solution for achieving high reliability and low latency *** study explores the potential of employing intelligent reflective surfaces(IRS)andUAVs as relay nodes to efficiently offload user computing tasks to theMEC server system ***,the user node accesses the primary user spectrum,while adhering to the constraint of satisfying the primary user peak interference ***,the UAV acquires energy without interrupting the primary user’s regular communication by employing two energy harvesting schemes,namely time switching(TS)and power splitting(PS).The selection of the optimal UAV is based on the maximization of the instantaneous signal-to-noise ***,the analytical expression for the outage probability of the system in Rayleigh channels is derived and *** study investigates the impact of various system parameters,including the number of UAVs,peak interference power,TS,and PS factors,on the system’s outage performance through *** proposed system is also compared to two conventional benchmark schemes:the optimal UAV link transmission and the IRS link *** simulation results validate the theoretical derivation and demonstrate the superiority of the proposed scheme over the benchmark schemes.

关键词： Unmanned aerial vehicle(UAV) intelligent reflective surface(IRS) energy harvesting computational offloading outage probability