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Computational study of combined effects of conduction-radiation and hydromagnetics on natural convection flow past magnetized permeable plate

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Applied mathematics and mechanics(English Edition) 2012年第6期33卷 731-748页

作者： m.ashraf S.ASGHAR m.A.HOSSAIN Department of mathematics COMSATS Institute of Information Technology Department of mathematics King Abdulaziz University Department of mathematics University of Dhaka

The computational study of the combined effects of radiation and hydro- magnetics on the natural convection flow of a viscous, incompressible, and electrically conducting fluid past a magnetized permeable vertical plate is presented. The governing non-similar equations are numerically solved by using a finite difference method for all values of the suction parameter and the asymptotic solution for small and large values of ~. The effects of varying the Prandtl number Pr, the magnetic Prandtl number Prm, the magnetic force parameter S, the radiation parameter Rd, and the surface temperature Ow on the coefficients of the skin friction, the rate of heat transfer, and the current density are shown graphically and in tables. An attempt is made to examine the effects of the above mentioned physical parameters on the velocity profile, the temperature distribution, and the transverse component of the magnetic field.

关键词： hydromagnetic fluctuating natural convection magnetized plate currentdensity heat transfer

Ion-induced kinetic electron emission from ~6LiF,~7LiF and mgF_2 thin films

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Chinese Physics B 2010年第8期19卷 344-349页

作者： S.Ullah A.H.Dogar m.ashraf A.Qayyum Pakistan Institute of Engineering and Applied Sciences NiloreIslamabadPakistan Physics Division Pakistan Institute of Nuclear Science and TechnologyP.O.NiloreIslamabadPakistan Optics Laboratories P.O.Box 1021IslamabadPakistan

Secondary electron yields for Ar^＋ impact on 6LiF, 7LiF and mgF2 thin films grown on aluminum substrates are measured each as a function of target temperature and projectile energy. Remarkably different behaviours of the electron yields for LiF and mgF2 films are observed in a temperature range from 25 ℃ to 300 ℃. The electron yield of LiF is found to sharply increase with target temperature and to be saturated at about 175 ℃. But the target temperature has no effect on the electron yield of mgF2. It is also found that for the ion energies greater than 4 keV, the electron yield of 6LiF is consistently high as compared with that of 7LiF that may be due to the enhanced contribution of recoiling 6Li atoms to the secondary electron generation. A comparison between the electron yields of mgF2 and LiF reveales that above a certain ion energy the electron yield of mgF2 is considerably low as compared with that of LiF. We suggest that the short inelastic mean free path of electrons in mgF2 can be one of the reasons for its low electron yield.

关键词： ion-induced electron emission alkali halides electronic stopping electron mean free path

Wheat-Exuded Organic Acids Influence Zinc Release from Calcareous Soils

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Pedosphere 2011年第5期21卷 657-665页

作者： m.A.mAQSOOD S.HUSSAIN T.AZIZ m.ashraf Institute of Soil and Environmental Sciences University of Agriculture Department of Soil Science University of Sargodha

Rhizosphere drives plant uptake of sparingly soluble soil zinc(Zn).An investigation with three experiments was conducted to study organic acid exudation by two contrasting wheat genotypes(Sehar-06 and Vatan),Zn fractions in 10 different calcareous soils from Punjab,Pakistan,and release of different soil Zn fractions by organic *** two genotypes differed significantly in biomass production and Zn accumulation under deficient and optimum Zn levels in nutrient *** a deficient Zn level,Sehar-06 released more maleic acid in the rhizosphere than *** soils used in the present study had very different physicochemical properties;their total Zn and Zn distribution among different fractions varied *** release behaviour was determined by extracting the soils with 0.005 mol L-1 citric acid or maleic *** parabolic diffusion model best described Zn release as a function of *** diffusion model fitting indicated more maleic acid-driven than citric acid-driven soil Zn mobility from different *** Zn release in six consecutive extractions during 24 h ranged from 1.85 to 13.58 mg kg-1 using maleic acid and from 0.37 to 11.84 mg kg-1 using citric *** the selected calcareous soils,the results of stepwise linear regression indicated significant release of Fe-mn oxide-bounded soil Zn by maleic acid and its availability to the Zn-effcient ***,release of maleic acid by plants roots played an important role in phytoavailability of Zn from calcareous soils.

关键词：小麦基因型石灰性土壤土壤锌有机酸分泌土壤理化性质扩散模型连续提取

Characterization of Endophytic microorganisms of Rice(Oryza sativa L.)Potentials for Blast Disease Biocontrol and Plant Growth Promoting Agents

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Phyton-International Journal of Experimental Botany 2023年第11期92卷 3021-3041页

作者： Shugufta Parveen Fayaz A.mohiddin m.ashraf Bhat Zahoor Ahmed Baba Fehim Jeelani m.Anwar Bhat Sajad Un Nabi Burhan Hamid Saba Bandey Farhanaz Rasool Zakir Amin Ibrahim Al-Ashkar muhammad Adnan Ayman El Sabagh Division of Plant Pathology Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia mountain Research Centre for Field Crops SKUAST-KashmirKhudwaniIndia Division of Genetics and Plant Breeding Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Division of microbiology Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Division of Statistics Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Division of Agronomy Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Indian Council of Agricultural Research-Central institute of Temperate Horticulture(ICAR-CITH) Old AirportRangrethSrinagarIndia Division of Plant Pathology Faculty of HorticultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirShalimarIndia Directorate of Extension Sher-e-Kashmir University of Agricultural Sciences and Technology of KashmirShalimarIndia Department of Plant Production College of Food and Agriculture SciencesKing Saud UniversityRiyadhSaudi Arabia College of Food Agricultural and Environmental SciencesThe Ohio State UniversityColumbusOHUSA Department of Agronomy Faculty of AgricultureUniversity of KafrelsheikhKafrelsheikhEgypt

One hundred twenty-five endophytic microorganisms were isolated from the roots,stems,and leaves of four prominent rice cultivars growing in temperate *** potential to combat rice blast disease and promote plant growth was *** dual culture tests highlighted the strong antagonistic activity of five fungal(ranging from 89%–70%)and five bacterial(72%–61%)*** examination focused on volatile compounds produced by selected isolates to counter the blast *** these,the highest chitinase(13.76μg mL−1)and siderophore(56.64%),was exhibited by Aspergillus flavus,and the highest HCN production was shown by Stenotrophomonas maltophilia(36.15μm mL−1).In terms of growth promotion traits,Aspergillus flavus and Enterobacter cloacae excelled in activities viz,phosphorous solubilization,ammonia production,auxin and gibberellic acid production,and nitrogen *** Identity of these endophytes was confirmed through molecular analysis as Trichoderma afroharzianum,Trichoderma harzianum,Penicillium rubens,Aspergillus flavus,Stenotrophomonas rhizophila,Stenotrophomonas maltophilia,Bacillus cereus,Enterobacter cloacae,and Bacillus *** greenhouse conditions,the highest disease control was shown by isolate Bacillus licheniformis and *** with an inhibition of 79%,followed by ***(77%)and ***(73%).The overall results of this study showed that Bacillus licheniformis and Stenotrophomonas rhizophila have great potential to be used as bio-stimulant and biocontrol agents to manage rice blast disease.

关键词： Endophytes phylogeny antagonistic activity Pyricularia phytohormones

A Study of Suspended Particulate matter in Lahore (Pakistan)

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Advances in Atmospheric Sciences 1990年第2期7卷 178-185页

作者： K.Hussain Ruby Riffat A.Shaukat m.ashraf Siddiqui Centre for Solid State Physics University of the PunjabNew campus Lahore 54590 (Pakistan)Department of Physics University of the PunjabNew Campus Lahore 54590 (Pakistan)Department of Physics University of the PunjabNew Campus Lahore 54590 (Pakistan)Institute of Geology University of the Punjab.New Campus Lahore 54590 (Pakistan).

The results obtained from an investigation of suspended particulate matter in the metropolitan city of Lahore (Pakistan) are reported and analysed in this paper. X-ray diffraction studies of the airborne matter collected from various urban and suburban sites show that non-clay minerals such as quartz, calcite and albite are contained in most of the samples in almost comparable amounts. Chemical analysis of some samples was carried out for complementing the x-ray diffraction data. The amount of quartz in the samples of dusty areas was found to be an order of magnitude more than in the samples of relatively cleaner areas. As the dust particles of these compounds are poor substrate for promoting nucleation of ice in the atmospheric clouds, they are liable to stay steadily in the atmosphere as pollutants.A comparison of the results of the airborne particulates and the soil samples collected from various sites show that the sources of quartz, calcite and albite in the airborne matter are both local and remote.

关键词： A Study of Suspended Particulate matter in Lahore Pakistan

Distribution,Etiology,molecular Genetics and management Perspectives of Northern Corn Leaf Blight of maize(Zea mays L.)

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Phyton-International Journal of Experimental Botany 2022年第10期91卷 2111-2133页

作者： m.ashraf Ahangar Shabir Hussain Wani Zahoor A.Dar Jan Roohi Fayaz mohiddin monika Bansal mukesh Choudhary Sumit K.Aggarwal S.A.Waza Khursheed Ahmad Dar Ayman El Sabagh Celaleddin Barutcular Omer Konuşkan mohammad Anwar Hossain mountain Research Centre for Field Crops Sher-e-Kashmir University of Agricultural Sciences and Technology of KashmirJammu&Kashmir192124India Dry Land Agriculture Research Station Rangreth Sher-e-Kashmir University of Agricultural Sciences and Technology of KashmirJammu&Kashmir191132India School of Agricultural Biotechnology Punjab Agricultural UniversityLudhiana141001India Indian Institute of maize Research PAU CampusLudhiana141001India College of Temperate Sericulture Sher-e-Kashmir University of Agricultural Sciences and Technology of KashmirJammu&Kashmir191132India Department of Agronomy Faculty of AgricultureKafrelsheikh UniversityKafr El-Sheikh33516Egypt Department of Field Crops Faculty of AgricultureSiirt UniversitySiirt56100Turkey Department of Field Crops Faculty of AgricultureUniversity ofÇukurovaAdana01330Turkey Department of Field Crops Faculty of AgricultureHatay Mustafa Kemal UniversityHatay31060Turkey Department of Genetics and Plant Breeding Bangladesh Agricultural UniversityMymensingh2202Bangladesh

maize is cultivated extensively throughout the world and has the highest production among ***,Northern corn leaf blight(NCLB)disease caused by Exherohilum turcicum,is the most devastating limiting factor of maize *** disease causes immense losses to corn yield if it develops prior or during the tasseling and silking stages of crop *** has a worldwide distribution and its development is favoured by cool to moderate temperatures with high relative *** prevalence of the disease has increased in recent years and new races of the pathogen have been reported *** fungus *** is highly variable in *** different management strategies have proved effective to reduce economic losses from NCLB,the development of varieties with resistance to *** is the most efficient and inexpensive way for disease manage*** resistance for NCLB governed by Ht genes is a race-specific resistance which leads to a higher level of ***,some Ht genes can easily become ineffective under the high pressure of virulent strains of the ***,it is imperative to understand and examine the consistency of the genomic locations of quantitative trait loci for resistance to NCLB in diverse maize *** breeding approaches for pyramiding resistant genes against *** in maize can impart NCLB resistance under high disease pressure ***,the genome editing approaches like CRISPR-cas9 and RNAi can also prove vital for developing NCLB resistant maize *** such this review delivers emphasis on the importance and current status of the disease,racial spectrum of the pathogen,genetic nature and breeding approaches for resistance and management strategies of the disease in a sustainable manner.

关键词： Northern corn leaf blight etiology Exherohilum turcicum pathogenic variability disease resistance management strategies

Wave propagation of a functionally graded plate via integral variables with a hyperbolic arcsine function

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 547-561页

作者： mokhtar Ellali mokhtar Bouazza ashraf m.Zenkour Smart structures Laboratory University of Ain TemouchentAin Temouchent 46000Algeria Department of Civil Engineering University Tahri Mohamed of BecharBechar 08000Algeria Department of mathematics Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Laboratory of materials and Hydrology(LmH) University of Sidi Bel AbbesSidi Bel Abbes 22000Algeria Department of mathematics Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33516Egypt

Several studies on functionally graded materials(FGms)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagation of the waves in *** work aims to explore the effects of changing compositional characteristics and the volume fraction of the constituent of plate materials regarding the wave propagation response of thick plates of *** model is based on a higher-order theory and a new displacement field with four unknowns that introduce indeterminate integral variables with a hyperbolic arcsine *** FGm plate is assumed to consist of a mixture of metal and ceramic,and its properties change depending on the power functions of the thickness of the plate,such as linear,quadratic,cubic,and inverse *** utilizing Hamilton’s principle,general formulae of the wave propagation were obtained to establish wave modes and phase velocity curves of the wave propagation in a functionally graded plate,including the effects of changing compositional characteristics of materials.

关键词： FGm plate effects of material properties wave propagation indeterminate integral variables inverse sinus hyperbolic function

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., 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

Amelioration of Salt Stress in Sugarcane (Saccharum officinarum L.) by Supplying Potassium and Silicon in Hydroponics

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Pedosphere 2010年第2期20卷 153-162页

作者： m.ashraf RAHmATULLAH R.AHmAD A.S.BHATTI m.AFZAL A.SARWAR m.A.mAQSOOD S.KANWAL University College of Agriculture University of Sargodha Institute of Soil & Environmental Sciences University of Agriculture Department of Crop Physiology University of Agriculture Sugarcane Research Institute Ayub Agricultural Research Institute

A hydroponics experiment was conducted to evaluate the role of potassium (K) and silicon (Si) in mitigating the deleterious effects of NaCl on sugarcane genotypes differing in salt *** salt-sensitive (CPF 243 and SPF 213) and two salt-tolerant (HSF 240 and CP 77-400) sugarcane genotypes were grown for six weeks in 1/2 strength Johnson's nutrient *** nutrient solution was salinized by two NaCl levels (0 and 100 mmol L 1 NaCl) and supplied with two levels of K (0 and 3 mmol L 1) and Si (0 and 2 mmol L 1).Applied NaCl enhanced Na + concentration in plant tissues and significantly (P ≤ 0.05) reduced shoot and root dry matter in four sugarcane ***,the magnitude of reduction was much greater in salt-sensitive genotypes than salt-tolerant *** salts interfered with the absorption of K + and Ca 2+ and significantly (P ≤ 0.05) decreased their uptake in sugarcane *** of K and Si either alone or in combination significantly (P ≤ 0.05) inhibited the uptake and transport of Na + from roots to shoots and improved dry matter yields under NaCl *** uptake,K + /Na + ratios,and Ca 2+ and Si uptake were also significantly (P ≤ 0.05) increased by the addition of K and/or Si to the root *** this study,K and Si-enhanced salt tolerance in sugarcane genotypes was ascribed to decreased Na + concentration and increased K + with a resultant improvement in K + /Na + ratio,which is a good indicator to assess plant tolerance to salt ***,further verification of these results is warranted under field conditions.

关键词：甘蔗属硅酸钾盐胁迫水培供给改良