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Comparative field performance of some agricultural crops under a canopy of Populus deltoides and Ulmus wallichiana

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Journal of Forestry Research 2013年第4期24卷 783-790页

作者： Tariq Hussian Masoodi Nasir ahmad Masoodi Sajad ahmad Gangoo Shah Murtaza Mushtaq Hillal ahmad Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir

The performance of maize, beans and sunflower was evalu- ated under a canopy ofPopulus deltoides and Ulmus wallichiana at Fac- ulty of Agriculture, Wadura. The germination, growth and yield of the three test crops were suppressed under both tree species. The reduction, however, decreased when the cultivation of test crops was continued for three years. The inhibition potential generally is in the order of P del- toides 〈 U. wallichiana for maize and sunflower and P. deltoides 〉 U. wallichiana for beans. Available soil N, P and K increased under the canopy of the selected tree species. The soils under U. wallichiana were more fertile than those under P deltoides. Chromatographic investigation of extracts showed that the soils under P deltoides and U. wallichiana differed in their composition of phenolic acids and phenolic glycocides. Except for caffic acid, all other allelochemicals disappeared and were no longer recovered in soil samples obtained after the second or third year of cultivation. Tree-crop compatibility can be explored in greater detail for improved management of traditional agro-ecosystems in Kashmir to increase the overall productivity of the land.

关键词： allelopathy agroforestry phenolic acids glycocides growthperformance yield

Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： Arshad ASHRAF imran ahmad Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. it is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. in the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., isk, i.e., 5-25 t/(ha·yr) and 7.5% area moderate risk, i.e., 25-50 t/(ha·yr) in the region. The risk was high, i.e., 50-100 t/(ha·yr) and very high, i.e., >100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. it is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility indus basin Land degradation Slope stabilization

Effects of Halloysite Nanotube Reinforcement in Expandable Graphite Based intumescent Fire Retardant Coatings Developed Using Hybrid Epoxy Binder System

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Chinese Journal of Polymer Science 2018年第11期36卷 1286-1296页

作者： Qandeel Fatima Gillan Faiz ahmad M.i.Abdul Mutalib Puteri S.M.Megat-Yusoff Sami Ullah Mechanical Engineering Department Universiti Teknologi PETRONAS31750 TronohPerakMalaysia Chemical Engineering Department Universiti Teknologi PETRONAS31750 TronohPerakMalaysiac Department of Mechanical Engineering University of Gujrat50700 GujratPakistan

in this study, the effects of halloysite nanotubes （HNTs） reinforcement in expandable graphite based intumescent fire retardant coatings （iFRCs） developed using a polydimethylsiloxane （PDMS）/phenol BA epoxy system were investigated. intumescent coating formulations were developed by incorporating different weight percentages of HNTs and PDMS in basic intumescent ingredients （ammonium polyphosphate/melamine/boric acid/expandable graphite, APP/MEL/BA/EG）. The performance of intumescent formulations was investigated by furnace fire test, Bunsen burner fire test, field emission electron microscopy （FESEM）, thermogravimetric analysis （TGA）, transmission electron microscopy （TEM）, and Fourier transform infrared analysis （FTiR）. The Bunsen burner fire test results indicated that the fire performance of HNTs and PDMS reinforced intumescent formulation has improved due to the development of silicate network over the char residue. improved expansion in char residue was also noticed in the formulation, SH（3）, due to the minimum decomposition of char carbon. FESEM and TEM results validated the development of silicate network over char layer of coating formulations. A considerable mass loss difference was noticed during thermal gravimetric analysis （TGA） of intumescent coating formulations. Reference formulation, SH（0） with no filler, degraded at 300 ~C and lost 50% of its total mass but SH（3）, due to synergistic effects between PDMS and HNTs, degraded above 400 ~C and showed the maximum thermal stability. XRD analysis showed the development of thermally stable compound mulltie, due to the synergism of HNTs and siloxane during intumescent reactions, which enhanced fire performance. FTiR analysis showed the presence of incorporated siloxane and silicates bonds in char residue, which endorsed the toughness of intumescent char layer produced. Moreover, the synergistic effect ofHNTs, PDMS, and other basic intumescent ingredients enhanced the polymer cross-linking in binder system an

关键词： Polydimethylsiloxane (PDMS) Halloysite nanotubes (HNTs) intumescent fire retardant coatings (iFRC) Thermogravimetric analysis (TGA) Transmission electron microscopy (TEM)

Geochemical indices of soil development on basalt rocks in arid to sub-humid climosequence of Central iran

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Journal of Mountain Science 2020年第7期17卷 1652-1669页

作者： ahmad HEiDARi Alireza RAHEB Soil Science Department College of Agriculture and Natural ResourcesUniversity of TehranKarajP.O.Box 4111Iran

Quantitative weathering indices are efficient tools in determining the soil development from the underlying *** order to evaluate the effects of climate on the soils developed under an arid to sub-humid climosequence in central iran,twenty soil-development indices were *** samples from six pedons were analyzed for routine physico-chemical and geochemical analyses using X-ray fluorescence(XRF).The lowest and highest calculated soil development indices were observed in the arid and sub-humid regions *** the studied indices,fifteen indices showed similar trends concerning the intensity of *** consistency of such trends reveals the feasibility of using these indices to evaluate basalt weathering rate and soil development in arid,semi-arid and sub-humid *** study demonstrated that,among the evaluated weathering indices,the Weathering index of Parker(WiP)and mass transfer coefficient(τ)were the most proper indices for predicting basalt weathering *** is due to the fact that these indices use the highly mobile earth elements which are the most sensitive elements in basalt chemical *** calculated indices were subdivided into three subgroups including the ratios of mobile/immobile,mobile/mobile and immobile/mobile elements based on the elements used in their *** state of soil evolution was more accurately predicted compared to the other subgroups using the mobile/immobile subgroup of ***,the weathering indices calculated using the mobile elements are better indicators of weathering intensity,soil formation and the exogenous processes across the arid to sub-humid climosequence.

关键词： Basalt Climosequence Geochemical properties Aridisols Mollisols inceptisols

Water Gas Shift Reaction： A Monte Carlo Simulation

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Chinese Physics Letters 2006年第9期23卷 2602-2605页

作者： Waqar ahmad Akhtar HUSSAiN Physics Research Division Pakistan Institute of Nuclear Science and Technology PO Nilore Islamabad Pakistan

The water gas shift （WGS） reaction is reacts with water on a catalytic surface a process of industrial importance to form CO2 and H2. We study this in this reaction carbon monoxide reaction with thermal （Langmuir- Hinshelwood） and non-thermal （precursor and Eley-Rideal） reaction mechanisms using the techniques of Monte Carlo computer simulation. The details of surface coverages and production rates are given as a function of CO partial pressure. The diffusion of species on the surface as well as their desorption from the surface is also introduced to include temperature effects. The phase diagrams of the system have been drawn to observe the behaviour of reacting species on the surface. The study reveals that the production rates are higher for non-thermal precursor mechanism and are in agreement with the experimental finding.

关键词： KiNETiC PHASE-TRANSiTiONS SURFACE-REACTiON MODEL HETEROGENEOUS CATALYSiS NiTROGEN CHEMiSORPTiON MECHANiSM TUNGSTEN DiAGRAM FACE

Accelerated D-Dimensional Compactified Universe in Gauss-Bonnet-Dilatonic Scalar Gravity from D-Brane/M-Theory

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Chinese Physics Letters 2008年第8期25卷 2785-2788页

作者： EL-NABULSi ahmad Rami Department of Nuclear and Energy Engineering Cheju National University Ara-dong 1 Jeju 690-756 South Korea

We discuss a particular d-dimensional Gauss- Ronnet-dilatonie universe compactified on S^1 motivated from Mtheory. We examine the time-evolution of the dynamical equations where many interesting consequences are revealed and discussed in some details. Under reasonable conditions, the discussed model can provide a mechanism to realize, in higher-dimensions （d 〉 4）, the accelerated expansion of the universe in the presence of dark energy, without the presence of phantom energy and without the contraction of some internal dimension.

关键词： COSMOLOGiCAL CONSTANT CHAPLYGiN-GAS DARK ENERGY QUiNTESSENCE SUPERNOVAE PLANETS OMEGA

An Optimized Method for Accounting information in Logistic Systems

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Computer Systems Science & Engineering 2023年第5期45卷 1595-1609页

作者： ahmad Mohammed Alamri ahmad Ali AlZubi Administrative Sciences Department Community CollegeKing Saud UniversityRiyadhSaudi Arabia Computer Science Department Community CollegeKing Saud UniversityP.O.Box 28095Riyadh11437Saudi Arabia

in the era of rapid information development,with the popularity of computers,the advancement of science and technology,and the ongoing expansion of iT technology and business,the enterprise resource planning(ERP)system has evolved into a platform and a guarantee for the fulfilment of company management procedures after long-term *** of developments in information technology,most manual accounting procedures are being replaced by computerized Accounting information Systems(AiS),which are quicker and more *** primary factors influencing the decisions of logistics firm trading parties are investigated in order to enhance the design of decision-supporting modules and to improve the performance of logistics enterprises through *** paper proposed a novel approach to calculate the weights of each information element in order to establish their important *** main purpose of this research is to present a quantitative analytic approach for determining the important information of logistics business collaboration ***,the idea of total orders and the significant degrees stated above are used to identify the optimal order of all information *** the three ways of marginal revenue,marginal cost,and business matching degree,the information with cumulative weights is which is deployed to form the data from the intersection of the best *** has the ability to drastically reduce the time and effort required to create a logistics business control/decision-making system.

关键词： Accounting information systems decisions systems corporate accounting logistic system

Suppression and synchronization of chaos in uncertain time-delay physical system

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 416-437页

作者： israr ahmad Muhammad Shafiq Department of Preparatory Studies Centre University of Technology and Applied SciencesNizwaOman Department of Electrical and Computer Engineering Sultan Qaboos UniversityOman

The mechanical horizontal platform(MHP)system exhibits a rich chaotic *** chaotic MHP system has applications in the earthquake and offshore *** article proposes a robust adaptive continuous control(RACC)*** investigates the control and synchronization of chaos in the uncertain MHP system with time-delay in the presence of unknown state-dependent and time-dependent *** closed-loop system contains most of the nonlinear terms that enhance the complexity of the dynamical system;it improves the efficiency of the *** proposed RACC approach(a)accomplishes faster convergence of the perturbed state variables(synchronization errors)to the desired steady-state,(b)eradicates the effect of unknown state-dependent and time-dependent disturbances,and(c)suppresses undesirable chattering in the feedback control *** paper describes a detailed closed-loop stability analysis based on the Lyapunov-Krasovskii functional theory and Lyapunov stability *** provides parameter adaptation laws that confirm the convergence of the uncertain parameters to some constant *** computer simulation results endorse the theoretical findings and provide a comparative performance.

关键词： chaotic horizontal platform system chaos suppression chaos synchronization robust adaptive control Lyapunov stability theory

Extra-Dimensional Cosmology with a Traversable Wormhole

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Chinese Physics Letters 2009年第9期26卷 37-40页

作者： EL-NABULSi ahmad Rami Department of Nuclear and Energy Engineering Cheju National University Ara-dong 1 Jeju 690-756 South Korea

We discuss many interesting and attractive features of a higher-dimensional cosmology with a static traversable wormhole dominated by a variable effective cosmological constant depending on the scale factor aft） as A... 详细信息

关键词： sea surface nonliear interaction numerical method