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Chinese Geographical Science 2020年第5期30卷 900-920页

作者： MALIK Sadhan pal subodh chandra Department of Geography University of BurdwanBurdwan 713104West BengalIndia

Downstream changes in channel morphology and flow over the ephemeral Dwarkeswar River in the western part of the Bengal Basin, eastren India were investigated. The river stretches from the Proterozoic Granite Gneiss Complex to the recent Holocene alluvium, forming three distinctive geomorphological regions across the river basin: the pediplane and upper and lower alluvial areas. Sixty cross-sections from throughout the main trunk stream were surveyed and the bankfull width, depth, cross-sectional area, and maximum depth were measured. Sediment samples from each location were studied and the flow velocity, stream power, Manning’s roughness coefficient, and shear stress were estimated. The results show that the bankfull channel cross-section area, width, width-to-depth ratio, and channel capacity increased between the beginning and middle of the river. Thereafter, the size of the river started to decrease in the lower alluvial area. This was characterized by gentle gradients, cohesive bank materials with grass cover, and channel switching. Within the lower part of the river, the channel capacity was observed to diminish as the drainage area increased. This increased the bankfull flow frequency and accelerated large floodwater losses in the floodplain via overbank flows and floodways.

关键词： bankfull channel width bankfull discharge Dwarkeswar River flat alluvial plain channel degradation overbank flow and flood

Assessment of soil erosion in the Irga watershed on the eastern edge of the Chota Nagpur Plateau,India

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Regional Sustainability 2024年第1期5卷 54-68页

作者： Ratan pal Buddhadev HEMBRAM Narayan chandra JANA Department of Geography the University of BurdwanWest Bengal-713104India

Human activities to improve the quality of life have accelerated the natural rate of soil *** turn,these natural disasters have taken a great impact on *** activities,particularly the conversion of vegetated land into agricultural land and built-up area,stand out as primary contributors to soil *** present study investigated the risk of soil erosion in the Irga watershed located on the eastern fringe of the Chota Nagpur Plateau in Jharkhand,India,which is dominated by sandy loam and sandy clay loam soil with low soil organic carbon(SOC)*** study used the Revised Universal Soil Loss Equation(RUSLE)and Geographical Information System(GIS)technique to determine the rate of soil *** five parameters(rainfall-runoff erosivity(R)factor,soil erodibility(K)factor,slope length and steepness(LS)factor,cover-management(C)factor,and support practice(P)factor)of the RUSLE were applied to present a more accurate distribution characteristic of soil erosion in the Irga *** result shows that the R factor is positively correlated with rainfall and follows the same distribution pattern as the *** K factor values in the northern part of the study area are relatively low,while they are relatively high in the southern *** mean value of the LS factor is 2.74,which is low due to the flat terrain of the Irga *** is a negative linear correlation between Normalized Difference Vegetation Index(NDVI)and the C factor,and the high values of the C factor are observed in places with low *** mean value of the P factor is 0.210,with a range from 0.000 to *** calculating all parameters,we obtained the average soil erosion rate of 1.43 t/(hm^(2)•a),with the highest rate reaching as high as 32.71 t/(hm^(2)•a).Therefore,the study area faces a low risk of soil ***,preventative measures are essential to avoid future damage to productive and constructive activities caused by soil *** study also ident

关键词： Soil erosion Soil organic carbon Rainfall-runoff erosivity factor Soil erodibility factor Slope length and steepness factor Cover-management factor Support practice factor Irga watershed

Extreme exposure of fluoride and arsenic contamination in shallow coastal aquifers of the Ganges delta,transboundary of the Indo-Bangladesh region

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Geoscience Frontiers 2024年第1期15卷 286-303页

作者： Dipankar Ruidas subodh chandra pal Tanmoy Biswas Asish Saha Abu Reza Md.Towfiqul Islam Department of Geography The University of BurdwanPurba BardhamanWest Bengal 713104India Department of Disaster Management Begum Rokeya UniversityRangpur 5400Bangladesh Department of Development Studies Daffodil International UniversityDhaka 1216Bangladesh

Globally,shallow aquifer groundwater(GW)has been severely affected in recent decades for both geogenic and anthropogenic *** hydro-geochemical characteristics of the GW change inconsistently with the addition of unwanted inorganic trace elements into the GW aquifer of the Indo-Bangladesh delta region(IBDR),such as arsenic(As)along with fluoride(F-)*** GW can have a negative impact on drinking water supplies and agricultural *** pollution can have serious adverse effects on the environment and human ***,the GW quality of this region is deteriorating progressively,and human health threatening by various life-threatening ***,the current study concentrated on the GW quality evaluation and prediction of possible health issues in the IBDR due to elevated contamination of As along with F-within GW aquifers by considering sixteen *** survey-based statistical methods such as entropy quality index(EWQI)combined with health risk index(HRI)was implemented for evaluating the As and F-sensitivity with the help of correlation testing and principal component *** study's outcome explains that a substantial portion of the IBDR has been vastly experiencing inferior GW quality,environmental issues,and health-related problems in dry and wet seasons,correspondingly for As and *** diagram verified the suitability of water that almost 55%of GW across the study area’s aquifers are unfit for drinking as well as cultivation of *** analysis and the Monte Carlo simulation method were also applied to assess the contaminant's concentration level and probable health risk *** present study concludes that the elevated exposure of As and F-pollution has to be monitored regularly and prevent unwanted GW contamination through implementing sustainable approaches and policies to fulfil the sustainable development goal 6(SDG-6)till 2030,ensuring the most basic human right of clean,safe,and hy

关键词： Indo-Bangladesh delta Entropy quality index Health risk index Monte Carlo simulation SDG-6

Modelling of piping collapses and gully headcut landforms: Evaluating topographic variables from different types of DEM

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Geoscience Frontiers 2021年第6期12卷 129-146页

作者： Alireza Arabameri Fatemeh Rezaie subodh chandra pal Artemi Cerda Asish Saha Rabin Chakrabortty Saro Lee Department of Geomorphology Tarbiat Modares UniversityTehran 14117-13116Iran Geoscience Platform Research Division Korea Institute of Geoscience and Mineral Resources(KIGAM)124 Gwahak-ro Yuseong-guDaejeon 34132South Korea Department of Geophysical Exploration Korea University of Science and Technology217 Gajeong-ro Yuseong-guDaejeon 34113South Korea Department of Geography The University of BurdwanBardhamanWest Bengal 713104India Soil Erosion and Degradation Research Group Departament de GeografiaUniversitat de ValènciaBlasco Ibàñez2846010-ValenciaSpain

The geomorphic studies are extremely dependent on the quality and spatial resolution of digital elevation model(DEM)*** unique terrain characteristics of a particular landscape are derived from DEM,which are responsible for initiation and development of ephemeral *** the topographic features of an area significantly influences on the erosive power of the water flow,it is an important task the extraction of terrain features from DEM to properly research gully ***,topography is highly correlated with other geo-environmental factors ***,climate,soil types,vegetation density and floristic composition,runoff generation,which ultimately influences on gully ***,terrain morphometric attributes derived from DEM data are used in spatial prediction of gully erosion susceptibility(GES)*** this study,remote sensing-Geographic information system(GIS)techniques coupled with machine learning(ML)methods has been used for GES mapping in the parts of Semnan province,*** research focuses on the comparison of predicted GES result by using three types of DEM *** Land Observation satellite(ALOS),ALOS World 3D-30 m(AW3D30)and Advanced Space borne Thermal Emission and Reflection Radiometer(ASTER)in different *** further progress of our research work,here we have used thirteen suitable geo-environmental gully erosion conditioning factors(GECFs)based on the multi-collinearity *** methods of conditional inference forests(Cforest),Cubist model and Elastic net model have been chosen for modelling GES ***’s importance of GECFs was measured through sensitivity analysis and result show that elevation is the most important factor for occurrences of gullies in the three aforementioned ML methods(Cforest=21.4,Cubist=19.65 and Elastic net=17.08),followed by lithology and *** of the model’s result was performed through area under curve(AUC)and other statistical *** valid

关键词： Digital elevation model(DEM) Gully erosion susceptibility(GES) Advanced land observation satellite(ALOS) Cforest Cubist Elastic net

Exploring the potential of artificial intelligence techniques in prediction of the removal efficiency of vortex tube silt ejector

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International Journal of Sediment Research 2023年第4期38卷 615-627页

作者： Sanjeev Kumar chandra Shekhar Prasad Ojha Nand Kumar Tiwari subodh Ranjan Department of Civil Engineering Indian Institute of Technology Department of Civil Engineering National Institute of Technology

A vortex tube silt ejector is a curative hydraulic structure used to remove sediment deposits from canals and is recognized as one of the most efficient substitutes for physically removing canal sediment. The spatially varied flow in the channel and the rotational flow behavior in the tube make the silt removal process complex. It is even harder to accurately predict the silt removal efficiency by traditional models accurately. However, artificial intelligence(AI) and machine learning approaches have emerged as robust substitutes for studying complex processes. Therefore, this research makes use of AI approaches; support vector machine(SVM), random forest(RF), random tree(RT), and multivariate adaptive regression spline(MARS) to compute the vortex tube silt ejection efficiency using the laboratory data sets. The outcomes of the artificial intelligence(AI)-based techniques also were compared with traditional models. It was found that the RT model(root mean square error, RMSE = 2.165, Nash Sutcliffe efficiency, NSE = 0.98) outperforms the other applied approaches which had relatively more significant result errors. The sensitivity analysis of the process depicts the extraction ratio as the key parameter in the computation of vortex tube silt ejector removal efficiency. The findings of the AI-based approaches discussed in the current study might be helpful for hydraulic engineers as well as researchers in the assessment of the removal efficiency of vortex tube silt ejectors.

关键词： Vortex tube silt ejector Support vector machine Random forest Random tree Multivariate adaptive regression spline

Magneto-Soret-Dufour thermo-radiative doublediffusive convection heat and mass transfer of a micropolar fluid in a porous medium with Ohmic dissipation and variable thermal conductivity

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Propulsion and Power Research 2022年第1期11卷 154-170页

作者： Dulal pal Bhuban chandra Das Kuppalapalle Vajravelu Department of Mathematics Siksha BhavanaVisva-Bharati UniversitySantiniketan731235West BengalIndia Department of Mathematics Rammohan College102/1 Raja Rammohan SaraniKolkata700009India Department of Mathematics Department of MechanicalMaterial and Aerospace EngineeringUniversity of Central FloridaOrlandoFL32816USA

This paper deals with developing a numerical boundary layer flow model to analyze convective heat transfer characteristics of a micropolar fluid past a vertical plate in a composite material with viscous-Ohmic dissipations in the presence of a transverse magnetic *** basic governing equations are solved numerically by using the Runge-Kutta-Fehlberg *** computed results reveal a reduction in the velocity,temperature,and microrotation profiles by increasing the Prandtl ***,the concentration distribution is enhanced by enhancing or decreasing Soret-Dufour parameter,and there seems to be decremented in the skin-friction coefficient values with Schmidt number.

关键词： Double diffusive convection Thermal radiation Micropolar fluid Soret-Dufour

Recent advances on pathogenesis,diagnosis,prevention,immunological aspects,and vectors of dengue:A review

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Asian Pacific Journal of Tropical Biomedicine 2023年第8期13卷 325-338页

作者： Mahesh chandra Sahu Rakesh Kumar Samantaray Aditi pal Sanghamitra Pati Division of Medical Entomology ICMR-Regional Medical Research CentreChandrasekharpurBhubaneswar-751023OdishaIndia ICMR-Regional Medical Research Centre ChandrasekharpurBhubaneswar-751023OdishaIndia

Dengue is a vector-borne disease caused by the dengue virus(DENV)of family *** fever is common in both developed and developing ***,approximately 400 million cases of dengue fever are reported annually,resulting in approximately 22000 *** cases in India have progressively increased in the last *** recent years,substantial progress has been made in understanding various aspects of dengue,including its pathogenesis,diagnosis,prevention strategies,immunological responses,and the role of vectors in its *** transmission of a positive RNA virus occurs through Aedes mosquitoes,specifically Aedes aegypti and Aedes *** virus is associated with a wide spectrum of symptoms,ranging from mild undifferentiated fever to severe hemorrhagic fever and shock,posing a potential threat to human *** are 4 types of antigenically distinct dengue serotypes(DENV-1 to DENV-4)and among them,DENV-2 is more lethal and extremely *** overcome the severity of dengue,Dengvaxia is administered to children 9 to 16 years old with evidence of previous dengue *** diagnosis of dengue is carried out by ELISA-based non-structural protein(NS1)and immunoglobulin ***,there are no specific biomarkers to identify severe disease *** factors and temperature play an important role in complex interaction among host,vector,and virus to manifest the severity of *** is a need for the refinement of climate-based disease forecasting models in India to effectively control the spread of *** mosquito repellent should be used periodically to kill or repel the Aedes mosquito to prevent the spread of dengue in humans.

关键词： Dengue Aedes mosquitoes Insecticide NS1 Immunoglobulin

Challenges and opportunities in the treatment of ulcerative colitis

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World Journal of Pharmacology 2015年第2期4卷 219-226页

作者： Sunil Ashokrao Nirmal Sunil Shivaji Gangurde Pratiksha Shankar Dumbre subodh chandra pal Subhash chandra Mandal Department of Pharmacognosy Pravara Rural College of Pharmacy Biotechnology Centre Post Graduate InstituteDr. PDKVMaharashtra 413736India Sarswati Vidyabhavan College of Pharmacy Department of Pharmacognosy NDMVP’s College of Pharmacy Pharmacognosy and Phytotherapy Research Laboratory Division of PharmacognosyDepartment of Pharmaceutical TechnologyJadavpur University

Ulcerative colitis(UC) is an inflammatory destructive disease of the large intestine occurred usually in the rectum and lower part of the colon as well as the entire colon. Drug therapy is not the only choice for UC treatment and medical management should be as a comprehensive whole. Many synthetic drugs are available for the treatment of UC like 5-aminosalicylic acid, oral or systemic corticosteroids, immunomodulator, etc. but these drugs are associated with many serious side effects after long term use or have certain disadvantage or not suitable for the use in some patients. In short synthetic drugs have many disadvantages and for this reason effective and safe alternative drug treatment for the UC is the challenge. Herbal drugs are found to be very promising results of the treatment of UC and enzymatic level. Researchers explored many herbal drugs for the treatment and even many more may found effective in the treatment of UC. At this point we feel herbal medicine is the better alternative for the treatment of UC.

关键词： Ulcerative colitis Herbal drugs Synthetic drugs

COVID-19 strict lockdown impact on urban air quality and atmospheric temperature in four megacities of India

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Geoscience Frontiers 2022年第6期13卷 279-290页

作者： subodh chandra pal Indrajit Chowdhuri Asish Saha Manoranjan Ghosh Paramita Roy Biswajit Das Rabin Chakrabortty Manisa Shit Department of Geography The University of BurdwanBardhaman713104West BengalIndia Center for Rural Development and Innovative Sustainable Technology Indian Institute of Technology KharagpurWest Bengal721302India India Smart Cities Fellow National Institute of Urban AffairsNew Delhi110003India Department of Geography Raiganj UniversityRaiganjUttar Dinajpur733134West BengalIndia

COVID-19 pandemic has forced to lockdown entire India starting from 24th March 2020 to 14th April 2020(first phase), extended up to 3rd May 2020(second phase), and further extended up to 17th May 2020(third phase) with limited relaxation in non-hotspot areas. This strict lockdown has severely curtailed human activity across India. Here, aerosol concentrations of particular matters(PM) i.e., PM,PM, carbon monoxide(CO), nitrogen dioxide(NO), sulphur dioxide(SO), ammonia(NH) and ozone(O), and associated temperature fluctuation in four megacities(Delhi, Mumbai, Kolkata, and Chennai)from different regions of India were investigated. In this pandemic period, air temperature of Delhi,Kolkata, Mumbai and Chennai has decreased about 3 ℃, 2.5 ℃, 2 ℃ and 2 ℃ respectively. Compared to previous years and pre-lockdown period, air pollutants level and aerosol concentration(-41.91%,-37.13%,-54.94% and-46.79% respectively for Delhi, Mumbai, Kolkata and Chennai) in these four megacities has improved drastically during this lockdown period. Emission of PMhas experienced the highest decrease in these megacities, which directly shows the positive impact of restricted vehicular movement. Restricted emissions produce encouraging results in terms of urban air quality and temperature, which may encourage policymakers to consider it in terms of environmental sustainability.

关键词： COVID-19 Aerosol Air pollutant Climate Megacity

Hydrogen absorption properties of amorphous(Ni0.6Nb0.4-yTay)100-xZrx membranes

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Progress in Natural Science:Materials International 2017年第1期27卷 126-131页

作者： O.palumbo F.Trequattrini N.pal M.Hulyalkar S.Sarker D.chandra T.Flanagan M.Dolan A.Paolone CNR-ISC U.O.S. La Sapienza Department of Physics Sapienza University of Rome Department of Chemical and Materials Engineering University of Nevada Department of Chemistry University of Vermont CSIRO QCAT Energy 1 Technology CourtPullenvale

Ni based amorphous materials have great potential as hydrogen purification membranes. In the present work the melt spun(Ni0.6Nb0.4-yTay)100-xZrxwith y=0, 0.1 and x=20, 30 was studied. The result of X-ray diffraction spectra of the ribbons showed an amorphous nature of the alloys. Heating these ribbons below T < 400 °C, even in a hydrogen atmosphere（1-10 bar）, the amorphous structure was retained. The crystallization process was characterized by differential thermal analysis and the activation energy of such process was obtained. The hydrogen absorption properties of the samples in their amorphous state were studied by the volumetric method,and the results showed that the addition of Ta did not significantly influence the absorption properties, a clear change of the hydrogen solubility was observed with the variation of the Zr content. The values of the hydrogenation enthalpy changed from37 k J/mol for x=30 to9k J/mol for x=20. The analysis of the volumetric data provides the indications about the hydrogen occupation sites during hydrogenation, suggesting that at the beginning of the absorption process the deepest energy levels are occupied, while only shallower energy levels are available at higher hydrogen content, with the available interstitial sites forming a continuum of energy levels.

关键词： Amorphous Ni based alloy ribbons High temperature X-ray diffraction DTA Activation energy Crystallization temperature Hydrogen solubility