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Evaluating location specific strain rates, temperatures,and accumulated strains in friction welds through microstructure modeling

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Defence Technology（防务技术） 2018年第2期14卷 83-92页

作者： javed akram Prasad Rao Kalvala Vikas Jindal Mano Misra Dept. of Metallurgical Engineering University of Utah Dept. of Metallurgical Engineering Indian Institute of Technology(BHU)

A microstructural simulation method is adopted to predict the location specific strain rates, temperatures, grain evolution, and accumulated strains in the Inconel 718 friction welds. Cellular automata based 2D microstructure model was developed for Inconel 718 alloy using theoretical aspects of dynamic recrystallization. Flow curves were simulated and compared with experimental results using hot deformation parameter obtained from literature work. Using validated model, simulations were performed for friction welds of Inconel 718 alloy generated at three rotational speed i.e., 1200, 1500, and1500 RPM. Results showed the increase in strain rates with increasing rotational speed. These simulated strain rates were found to match with the analytical results. Temperature difference of 150 K was noticed from center to edge of the weld. At all the rotational speeds, the temperature was identical implying steady state temperature(0.89 T_m) attainment.

关键词： Microstructure modeling Dynamic recrystallization Friction welding Inconel 718 EBSD Hot deformation Strain map

Low temperature friction stir welding of P91 steel

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Defence Technology（防务技术） 2016年第4期12卷 285-289页

作者： Prasad Rao KALVALA javed akram Mano MISRA Damodaram RAMACHANDRAN Janaki Ram GABBITA University of Utah Salt Lake City USA SSN College of Engineering Kalavakkam India Indian Institute of Technology Madras Chennai India

Bead-on-plate friction stir welds were made on P91 alloy with low and high rotational speeds(100 and 1000 RPM) to study their effects on weld microstructural changes and impression creep behavior. Temperatures experienced by the stir zone were recorded at the weld tool tip. Different zones of welds were characterized for their microstructural changes, hardness and creep behavior(by impression creep tests). The results were compared with submerged arc fusion weld. Studies revealed that the stir zone temperature with 100 RPM was well below A_(c1) temperature of P91 steel while it was above A_(c3) with 1000 RPM. The results suggest that the microstructural degradation in P91 welds can be controlled by low temperature friction stir welding technique.

关键词： Friction stir welding P91 Low temperature Martensite Carbides Impression creep

From Molecular Pathology of COVID-19 to Nigella Sativum as a Treatment Option:Scientific Based Evidence of Its Myth or Reality

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Chinese Journal of Integrative Medicine 2022年第1期28卷 88-95页

作者： Muhammad Atif Farrah Naz Junaid Akhtar Muhammad Imran Sidrah Saleem javed akram Muhammad Imran Muhammad Ikram Ullah Department of Clinical Laboratory Sciences College of Applied Medical SciencesJouf UniversitySakaka(75471)Saudi Arabia Department of Microbiology Government College UniversityFaisalabad(38000)Pakistan Department of Microbiology University of Health SciencesLahore(54600)Pakistan Department of Allied Health Sciences Sargodha Medical CollegeUniversity of SargodhaSargodha(40100)Pakistan University of Health Sciences Lahore(54600)Pakistan University Institute of Diet and Nutritional Sciences Faculty of Allied Health SciencesThe University of LahoreLahore(54590)Pakistan

COVID-19 virus is a causative agent of viral pandemic in human beings which specifically targets respiratory system of humans and causes viral *** unusual viral pneumonia is rapidly spreading to all parts of the world,currently affecting about 105 million people with 2.3 million *** review described history,genomic characteristics,replication,and pathogenesis of COVID-19 with special emphasis on Nigella sativum(***)as a treatment *** seeds are historically and religiously used over the centuries,both for prevention and treatment of different *** review summarizes the potential role of *** seeds against COVID-19 infection at levels of in silico,cell lines and animal models.

关键词： coronavirus nCoV-19 COVID-19 Nigella sativum review

Prioritization of Sub-Watersheds in Ruparel Watershed, Rajasthan Based on Morphometric and Land Use/Land Cover Analysis Using Remote Sensing and GIS

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International Journal of Geosciences 2022年第2期13卷 138-154页

作者： Munahzah Meraj akram javed Department of Geology Aligarh Muslim University Aligarh India

Watershed prioritization is considered as the most significant aspect in watershed resource management and development program. The present work attempts to prioritize seventeen sub-watersheds in Ruparel watershed of Alwar district of Rajasthan, India. For prioritization of sub-watersheds, morphometric and land use/land cover (LULC) analysis were performed using remote sensing and GIS. Base map of the study area has been derived from SOI toposheet on 1:50,000 scale whereas LULC mapping was done using IRS P6 LISS III data. Standard methods for drainage morphometry have been followed for computing morphometric parameters such as linear and shape for seventeen sub-watersheds and allotted ranks based on their relationship with erodibility and a compound value has been calculated for final ranking. Five main LULC categories were computed and were assigned priority ranks and subsequently a compound parameter was determined for final ranking. Integration of both morphometric and LULC results reveal that SBW5, SBW7, SBW12 and SBW16 are the common sub-watersheds that fall under high priority, SBW3 falls under Medium category and SBW11 comes under low priority. The results of the analysis can be used to identify the sub-watersheds which need immediate restoration and will eventually help in watershed resource management for sustainable development.

关键词： Prioritization Watershed Resource Management Morphometry Land Use/Land Cover Analysis

Morphometric Behavior of Shahzad Watershed, Lalitpur District, Uttar Pradesh, India: A Geospatial Approach

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Journal of Geographic Information System 2022年第3期14卷 193-220页

作者： Tanzeel Khatoon akram javed Interdisciplinary Department of Remote Sensing and GIS Applications Aligarh Muslim University Aligarh India Department of Geology Aligarh Muslim University Aligarh India

Morphometric parameters are an important aspect for understanding the hydrological and morphological behaviour of the watershed. The present study is carried out in the region of the Bundelkhand region (India) which is socio-economically backward and has a history of frequent drought hence studying the watershed characteristics with reference to morphometric analysis becomes important. The remote sensing and GIS technique has been utilized to mathematically quantify the parameters of the Shahzad watershed. The watershed is mainly fed by the Shahzad River (a tributary of Jamini River) flowing from south to north direction contributing the area of 1100 km2. The various morphometric aspect viz., linear, aerial, relief and morpho-tectonic parameters indicate that the watershed is elongated in shape and is slightly uplifted from the right side in the southern part. Moreover, the watershed experiences low dissection and low run-off discharge there by indicating less erosion in the area. The other factors like drainage density, drainage frequency, infiltration number and length of over land flow indicate that the watershed has high permeability and infiltration capacity. Through this study, it can be concluded that remote sensing and GIS can be fruitfully utilized in analysing the morphometric behaviour of the region. This helps the researcher, planner and stakeholders to establish the relationship between watershed characteristics, thereby resulting in watershed management and sustainable resource management.

关键词： Shahzad Watershed Morphometric Analysis Watershed Characteristics Remote Sensing GIS

Assessment of Land Use Land Cover Change Detection Using Geospatial Techniques in Southeast Rajasthan

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Journal of Geoscience and Environment Protection 2021年第12期9卷 299-319页

作者： Nuzhat Fatima akram javed Department of Geology Aligarh Muslim University Aligarh India

Change analysis acquires effective information in the form of maps and statistical data which becomes the central component in spatial planning, monitoring environmental changes, management and utilization of land. The present study makes an attempt to assess the changes in land use land cover using multi-temporal satellite data in south-east Rajasthan. These maps were derived from geocoded dia-positive False Color Composites (FCC’s) of IRS 1991, 2001, 2010 & 2018 using Arc GIS platform. The present study demonstrates the extension, approach and result of change analysis which might be helpful for decision making and sustainable growth. The landscape has been divided into 12 categories. Mining and its associated features were increased whereas forest and open scrub cover shows decreasing trend during the study period. The former increased by 23.82 km2 while the later shrunk by 26.08 km2. Most significant changes are also witnessed in settlement and industrial areas which shows increment by 8.8 km2 and 1.33 km2. Stone quarrying has destroyed arable land, natural vegetation cover, topsoil, subsoil and consequently the soil profile of the area. On the other hand cultivated land is increasing due to the conversion of uncultivated land and scrub cover with facilitation of irrigation and modern agricultural activities under different government schemes. The study shows that the area of 184.88 km2 has undergone significant sp

关键词： IRS Data GIS Land Use Land Cover Mining South-East Rajasthan India

Land Use/Land Cover (LULC) Dynamics in a Semi-Arid Watershed in Eastern Rajasthan, India Using Geospatial Tools

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Journal of Geographic Information System 2022年第6期14卷 612-633页

作者： Munahzah Meraj akram javed Department of Geology Aligarh Muslim University Aligarh India

Land use/land cover (LULC) change analysis has become a unique approach in determining the extent of degradation of natural resources within a given period of time. Remote sensing and GIS techniques have proved to be efficient tools for mapping and analyzing LULC changes over the last few decades. LULC change analysis has been carried out in Ruparel watershed which is situated in Alwar district, Eastern Rajasthan, India, based on visual image interpretation and change detection analysis of multi-temporal satellite data pertaining to IRS-P6 LISS III data of 2004 (Path-Row 95:52), IRS-P6 LISS III of 2014 (Path-Row 95:52) and IRS-R2A LISS III data of 2021. Visual image interpretation led to the delineation of 13 LULC classes using ArcGIS 10.5 software and include categories such as cultivated land, fallow land dense forest, open forest, degraded forest, open scrub, gullied/ravenous land, settlement/built-up land, River/waterbody, dry waterbody/dry river, plantation, barren/rocky/stony waste, and stone quarry. Results of the analysis depict significant LULC changes that have taken place in the area from 2004 to 2021. LULC categories such as cultivated land and settlement/built-up land have reported major changes in terms of their increase with 56.42 km2 (4.63%) and 31.9 km2 (2.63%) respectively primarily because of an increase in population. Likewise, the dense forest has reported a decrease of 33.78 km2 (2.78%) in its area and has been converted into degraded forest i.e., 32.04 km2 (2.64%) and open forest 2.85 km2 (0.24%) due to increased human exploitation of forest resources and mining activities taking place within the forested area. The study area needs the immediate attention of policymakers and stakeholders as the study area being part of the National Capital Region (NCR) will see excessive in-migration of the population in coming years which will further deplete the precious resources in the area.

关键词： Land Use/Land Cover Ruparel Watershed Change Detection Analysis Remote Sensing and GIS

Spatio-Temporal Land Cover Dynamics in Open Cast Coal Mine Area of Singrauli, M.P., India

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Journal of Geographic Information System 2012年第6期4卷 521-529页

作者： Imran Khan akram javed Department of geology Aligarh Muslim University Aligarh India

Singrauli is an opencast coal mining area where large scale mining activities are going on continuously, land use/land cover studies are of vital importance to observe the changes in the land use/land cover. The present study utilizes multi-spectral/multi-temporal data of Indian Remote Sensing Satellite (IRS) LISS II geocoded (FCC) of 4th May 1993 and LISS III of 4th May 2010 for thematic mapping. Survey of India toposheet 63L/12 on scale 1:50,000 were used for preparation of base map which was overlaid on the FCC for land use/land cover mapping through visual interpretation. Visual interpretation of satellite imagery led to the identification of 15 land use/land cover categories such as dense forest, open forest, open scrub, plantation, cultivated land, uncultivated land, mining pit, overburden dumps, wasteland and settlement. The ground truth verification was carried out in key areas to rectify the errors in generated maps and then land use/land cover maps were finalized. The comparative analysis of land use/land cover shows that dense forest has been degraded to open forest, open scrubs and mining pits due to the expansion of mining activity. Open scrubs has increased, overburden dumps has increased, settlement has also increased, cultivated land has decreased and changed into uncultivated land and wasteland. It has also been observed that the plantation has been done on overburden dumps and residential colonies of NCL and NTPC. It has been identified that the main drivers which has increased the rate of change in land use/land cover are mainly coal mining activities and industrial expansion.

关键词： Change Detection Mining and Industrialization Land Degradation

Identification of Artificial Recharge Sites in Manchi Basin, Eastern Rajasthan (India) Using Remote Sensing and GIS Techniques

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Journal of Geographic Information System 2014年第2期6卷 162-175页

作者： Subah Rais akram javed Department of Geology Aligarh Muslim University Aligarh India

The present study is an attempt to prepare a water resource development action plan for Manchi basin in Eastern Rajasthan (India) using remote sensing and GIS techniques. Satellite data have proven to be very useful for surface study, especially in the preparation of land use/land cover and geomorphological map. Morphometric parameters are analyzed to understand the basin characteristics and its influence on the water resources for instance bifurcation ratio indicates high surface run off and low recharge in SB-I, IV, V. Low drainage density ranges from 2.41 (SB-IV) to 2.99 (SB-V) km/km2, with an average of 2.72 km/km2 showing permeable strata, dense vegetation and low relief. Analysis of shape parameters i.e. elongation ratio and circularity ratio suggest that Manchi basin is elongated in shape. Whereas, slope, geology and geomorphological mapping is done to demarcate groundwater potential zones for future exploration in the study area. Slope is inversely proportional to infiltration. Therefore, sub-basin areas having gentle slope permits less runoff and more infiltration as in alluvial plains and vice versa where hills and ridges are present. The integrated study helps in designing suitable sites for constructing water harvesting structures. Check dams, percolation tanks and nala bund are proposed at 1st, 2nd or 3rd drainage orders at SB-I and SB-IV with ravenous land (open scrub), uncultivated land, open forest & exposed rock present. Nala bund & check dam are proposed at SB-II & SB-V whereas, at SB-III check dams & percolation tanks are proposed so as to conserve the natural resources present in the basin. Finally, the best feasible water harvesting structures have been proposed within the sub-basins area using remote sensing and GIS techniques.

关键词： Morphometric Analysis DEM Hydrogeomorphology Remote Sensing GIS