检索结果-南通市图书馆

Suspended sediment dynamics in the meltwater of Chhota Shigri glacier, Chandra basin, Lahaul-Spiti valley, India

Journal of Mountain Science 2018年第1期15卷 68-81页

作者： Virendra Bahadur SINGH al.ramanathan School of Environmental Sciences Jawaharlal Nehru University

Present study shows suspended sediment dynamics in the meltwater of Chhota Shigri glacier,Himachal Pradesh,India for different melt seasons during the period *** suspended sediment concentration in the meltwater was found during the month of July 2011,2012 and 2014 constituting to 55.2%,48.3% and 46.9%,*** in 2013,maximum suspended sediment concentration was observed in August accounting for46.1% of the *** the other hand,maximum suspended sediment load was monitored in the month of July 2011,2012 and 2014 constituting 59.5%,63% and 55.7% of the total,*** in2013,maximum suspended sediment load was observed in the month of August accounting for 49.8% of the total suspended sediment *** distribution of suspended sediment concentration(SSC)and suspended sediment load(SSL)in the Chhota Shigri glacier shows higher value of SSC and SSL during the study period 2012 and 2013,which may be due to the presence of high glacial runoff and negative mass balance of the studied area during these time *** diurnal variation has been observed in the SSC of *** correlation was observed between SSC and SSL with *** the other hand,SSC and SSL also showed strong exponential correlation with air temperature of the studied *** yield from the catchment of Chhota Shigri glacier is high during the peak melt season(July and August)and low during the late melt season(September and October).The average value of erosion rate for Chhota Shigri glacier basin during the study period 2011-2014 was calculated to be 1.1mm/yr,which is lower than the average erosion rate of other Himalayan glaciers such as Rakiot,Chorabari and Gangotri glaciers,which may be caused by its geological setting containing high erosion resistant rocks such as granite,granite gneiss and porphyritic granite.

关键词： Suspended sediment concentration Hysteresis Sediment yield Erosion rate Western Himalaya Chhota Shigri glacier

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

DIAGNOSIS OF WAVE ACTIVITY OVER RAINBAND OF LANDFalL TYPHOON

引用

Journal of Tropical Meteorology 2009年第2期15卷 121-129页

作者：冉令坤 Abdul REHIM al ramanathan Institute of Atmospheric Physics Chinese Academy of Sciences Bangladesh Meteorological Department School of Environmental Science Jawaharlal Nehru University

A generalized wave-activity density, which is defined as an absolute value of production of three-dimensional vorticity vector perturbation and gradient of general potential temperature perturbation, is introduced and its wave-activity law is derived in Cartesian coordinates. Constructed in an agoestrophic and nonhydrostatie dynamical framework, the generalized wave-activity law may be applicable to diagnose mesoscale weather systems leading to heavy rainfall. The generalized wave-activity density and wave-activity flux divergence were calculated with the objective analysis data to investigate the character of wave activity over heavy-rainfall regions. The primary dynamical processes responsible for disturbance associated with heavy rainfall were also analyzed. It was shown that the generalized wave-activity density was closely correlated to the observed 6-h accumulative rainfall. This indicated that the wave activity or disturbance was evident over the frontal and landfall-typhoon heavy-rainfall regions in middle and lower troposphere. For the landfall-typhoon rainband, the portion of generalized wave-activity flux divergence, denoting the interaction between the basic-state cyclonic circulation of landfall typhoon and mesoscale waves, was the primary dynamic process responsible for the evolution of generalized wave-activity density.

关键词： dynamic meteorology wave-activity density wave-activity flux divergence landfall typhoon, heavy-rainfall event

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Humic substances:Structure,function and benefits for agroecosystems—a review

引用

Pedosphere 2023年第2期33卷 237-249页

作者： Jaya TIWARI al ramanathan Kuldeep BAUDDH John KORSTAD Department of Community Medicine and School of Public Health Postgraduate Institute of Medical Education and ResearchChandigarh 160012(India) Skill faculty of Applied Sciences and Humanities Shri Vishwakarma Skill UniversityPalwal Haryana 121102(India) School of Environmental Sciences Jawaharlal Nehru UniversityNew Delhi 110067(India) Department of Environmental Sciences Central University of JharkhandRanchi 835205(India) Department of Biology and Global Environmental Sustainability Oral Roberts UniversityTulsa OK 74171(USA)

The increasing global demand for food production,often causing excessive use of chemical fertilizers,has led to the deterioration of soil *** action is required to restore soil health in a sustainable *** review advocates switching to use of organic matter(manure and compost)that contains vital nutrients for plant growth and helps restore soil *** substances(HSs),derived from degraded plant remains and found ubiquitously in nature,are an important source of organic *** application of HSs to soil enhances essential nutrient supply and assimilation of atmospheric CO_(2)due to increasing biomass *** HS application globally can help lower atmospheric CO_(2)concentrations and create a sustainable agricultural ***,the process of humification and the molecular structure of HSs remain poorly understood subjects in soil ***,it is imperative to understand the mechanisms underlying various roles of HSs in *** review offers an insight into the various structural and functional aspects of HSs,particularly fulvic acid and humic *** dynamic and interactive nature of HSs creates a framework for sustainable agriculture.

关键词： fulvic acid humic acid humin humus nutrient supply soil health sustainable agriculture

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Understanding arsenic behavior in alluvial aquifers:Evidence from sediment geochemistry,solute chemistry and environmental isotopes

引用

Geoscience Frontiers 2024年第5期15卷 222-238页

作者： Shailesh Kumar Yadav al.ramanathan Chidambaram Sabarathinam alok Kumar Manoj Kumar Anshula Dhiman School of Environmental Sciences Jawaharlal Nehru UniversityNew Delhi 110067India Water Research Center Kuwait Institute for Scientific ResearchKuwait Department of Environmental Studies University of Delhi110007India Department of Earth and Environmental Sciences Indian Institute of Science Education and Research MohaliSector 81140306India

The hydro-geochemistry and isotopic variations in groundwater,coupled with sediment geochemistry,were investigated in the Middle Gangetic Plain,India,to better understand the aquifer dynamics that influence the arsenic(As)evolution and ***-four groundwater samples,thirteen River water samples,and two sediment cores(33 mbgl)were *** samples were analyzed for major ions and trace metals,including As and stable isotopic variability(δ^(2)H,δ^(18)O,andδ^(13)C).The study area was categorized into older and younger alluvium based on existing geomorphological *** alluvium exhibits higher As enrichment in sediment and groundwater,ranging of 2.59–31.52 mg/kg and bdl to 0.62 mg/*** samples were thermodynamically more stable with As(OH)_(3)species ranging from 88.5%to 91.4%and FeOOH from 69%to 81%,*** and mineralogical analysis suggested goethite and siderite act as a source and sink for ***,statistical analysis suggested reductive dissolution as the primary mechanism for As mobilization in the study ***-temporal analysis revealed elevated concentrations of As in the central and northeastern regions of the study *** isotope(δ^(2)H andδ^(18)O)analysis inferred active recharge conditions primarily driven by *** depleted d-excess value and enrichedδ^(18)O in the groundwater of younger alluvium indicate the effect of groundwater recharge with significant evaporation *** recharge potentially decreased the quantity of arsenic in groundwater,whereas evaporation enrichment increased *** infiltration during recharge introduces oxygenated water into the aquifer,leading to changes in the redox conditions and facilitating biogeochemical *** carbon isotope(δ^(13)C)results suggest that high microbial activity in younger alluvium promotes As leaching from sediment into the groundwater.

关键词： Groundwater recharge Reductive dissolution Older alluvium Younger alluvium Ghazipur Stable isotope

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Regional representation of glaciers in Chandra Basin region,western Himalaya,India

引用

Geoscience Frontiers 2017年第4期8卷 841-850页

作者： Pratima Pandey S.Nawaz ali al.ramanathan P.K.Champati ray G.Venkataraman Geosciences and Geohazards Department Indian Institute of Remote Sensing Birbal Sahni Institute of Paleosciences School of Environmental Science Jawaharlal Nehru University Centre of Studies in Resource Engineering Indian Institute of Technology

Hamtah and Chhota Shigri are two nearby,well monitored glaciers of western Himalaya,lying in the same climatic zone and driven by the same climatic *** this study,topographical characteristics of both the glacier have been explored to understand the role of topography in controlling the glacier ***,their topographical characteristics and possible response towards climatic variations have been compared with each other and also with that of the other glaciers in the basin to find out the suitability of these two glaciers to be considered as representative of the *** sensor and multi temporal remote sensing data have been used to carry out to fulfill the *** is found that being in the same climatic zone,the mean accumulation area ratio of Chhota Shigri is 54%and Hamtah is 11%between 1980 and *** comparison to Hamtah,Chhota Shigri glacier has a small upslope area,low compactness ratio indicating the ability of the glacier to receive direct precipitation and solar *** analysis revealed that the Chhota Shigri glacier has a closer resemblance with the other glaciers in the region than Hamtah ***,the topographical settings of Chhota Shigri glacier are suitable for recording and reflecting year-to-year climatic variations.

关键词： Himalaya Glacier Regional representation Topography Remote sensing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Assessment of Methane Flux from Municipal Solid Waste (MSW) Landfill Areas of Delhi, India

引用

Journal of Environmental Protection 2011年第4期2卷 399-407页

作者： Manju Rawat al ramanathan 不详

Carbon dioxide, methane and nitrous oxide are the major Greenhouse Gases (GHG’s), which emit from landfill areas and contribute significantly to global warming. Moreover, that the global warming potential of methane is 21 times higher than that of carbon dioxide and it has highest generation (60%) than other gases. Therefore, there is immense concern for its abatement or utilization from landfill areas. Compared to the west, the composition of municipal solid waste (MSW) in developing countries has higher (40% - 60%) organic waste. This would have potential to emit higher GHG’s from per ton of MSW compared to developed world. Beside that landfills areas in India are not planned or en- gineered generally low lying open areas, where MSW is indiscriminate disposed. This leads to uncontrolled emission of trace gases, foul smell, bird menace, ground and surface water pollution etc. Due to scarcity of land in big cities, mu- nicipal authorities are using same landfill for nearly 10 - 20 years. Hence, the possibility of anaerobic emission of GHG’s further increases. In the present paper we had quantified the methane emission from three MSW landfill areas of Delhi i.e., Gazipur, Bhalswa and Okhla. The results showed that the range of methane emission various in winter from 12.94 to 58.41 and in Summer from 82.69 - 293 mg/m2/h in these landfill areas. The paper has also reviewed the literature on methane emission from India and the status of landfill areas in India.

关键词： Landfill Municipal Solid Waste GHG Emission India

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Characterisation of Municipal Solid Waste Compost (MSWC) from Selected Indian Cities—A Case Study for Its Sustainable Utilisation

引用

Journal of Environmental Protection 2013年第2期4卷 163-171页

作者： Manju Rawat al. ramanathan T. Kuriakose School of Environmental Sciences Jawaharlal Nehru University New Delhi India

Utilisation of Municipal Solid Waste is important to curb the ever rising demand of scarce land for its disposal. Changing life style patterns, particularly in urban areas, has led to increase in generation of MSW. Municipal solid waste from Indian cities estimated to have 40% - 60% organic matter, which could be recycled as compost. The most suitable way to recycle it with low investment is aerobic composting using windrow method. With the compliance of Municipal Solid Waste (Management and Handling) Rules 2000, many cities in India are making compost with organic portion of MSW. Before applying MSWC for agricultural uses, it is important to inventories heavy metals in compost to assess its toxicity. In the present study the compost samples were quantified for its toxicity from three highly populated cities of India, i.e., Delhi (Capital of India), Ahmedabad (Gujarat) and Bangalore (Karnataka). The MSWC samples were analysed for total heavy metals and in extractable fractions. Few samples were found with higher concentration of metals then the prescribed limits for its application as compost in Indian MSW rules, whereas, samples have not showed significant heavy metals concentration in extractable fractions. Therefore, studied MSW compost samples had demonstrated its suitability to use as green compost.

关键词： Municipal Solid Waste Compost Indian Cities Fractionation Heavy Metals

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Electrochemical capacitance of nanostructured ruthenium- doped tin oxide Sn1-xRuxO2 by the microemulsion method

引用

Frontiers of Materials Science 2017年第4期11卷 385-394页

作者： ramanathan SARASWATHY Department of Physics Velammal Institute of Technology Panchetti Thiruvallur-601204 India

Synthesis of nanostructured Ru-doped SnO2 was successfully carried out using the reverse microemulsion method. The phase purity and the crystallite size were analyzed by XRD. The surface morphology and the microstructure of synthesized nanoparticles were analyzed by SEM and TEM. The vibration mode of nanoparticles was investigated using FTIR and Raman studies. The electrochemical behavior of the Ru- doped SnO2 electrode was evaluated in a 0.1 mol/L Na2SO4 solution using cyclic voltammetry. The 5% Ru-doped SnO2 electrode exhibited a high specific capacitance of 535.6 Fig at a scan rate 20 mV/s, possessing good conductivity as well as the electro- cycling stability. The Ru-doped SnO2 composite shows excellent electrochemical properties, suggesting that this composite is a promising material for supercapacitors.

关键词： reverse microemulsion tin oxide nanomaterials supercapacitor electrochemical property

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An Efficient SDFRM Security System for Blockchain Based Internet of Things

引用

Intelligent Automation & Soft Computing 2023年第2期35卷 1545-1563页

作者： Vivekraj Mannayee Thirumalai ramanathan Faculty of Mechanical Engineering Anna UniversityChennai600025Tamil NaduIndia Department of Mechanical Engineering Dr.N.G.P.Institute of Technology641048Tamil NaduIndia

Blockchain has recently sparked interest in both the technological and businessﬁ*** Internet of Things's(IoT)core principle emerged due to the connectivity of several new technologies,including wireless technology,the Inter-net,embedded automation systems,and micro-electromechanical ***-facturing environments and operations have been successfully converted by implementing recent advanced technology like Cloud Computing(CC),Cyber-Physical System(CSP),Information and Communication Technologies(ICT)and Enterprise Model,and other technological innovations into the fourth indus-trial revolution referred to as Industry *** management is deﬁned as the pro-cess of accumulation in order to make better business decisions,and process,secure and store information about a *** the incipient model,there are interconnected contrivances and Machine-to-Machine(M2M)interactions,and transaction data are stored on the *** is a challenging aspect that must be punctiliously considered during the design and development phases of a *** this research article,we proposed a Secure and Distributed Framework for Resource Management(SDFRM)in Industry 4.0 environments within a distribu-ted and collaborative Industry 4.0 system,the dynamic and trust-based Distributed Management Framework(DMF)of shared resource *** issues are focused by taking into account of the traditional characteristics of IoT/Industrial Internet of Things’(IIoT)-predicated environments,an SDFRM in Industry 4.0 environments within a distributed and collaborative Industry 4.0 ***,to ensure strong privacy over the procedures associated with Access Control(AC),a privacy-preserving method is proposed and integrated into the *** proposed DMF,based on blockchain technology and peer-to-peer networks,allows dynamic access management and system governance without using third parties who could be *** worked hard to design and implement the pro-posal to demonstrate its

关键词： Internet of things blockchain data privacy security system distributed management IIoT

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Processing map for hot working of SiC_p/7075 al composites

引用

Transactions of Nonferrous Metals Society of China 2010年第4期20卷 668-674页

作者： M.RAJAMUTHAMILSELVAN S.ramanathan R.KARTHIKEYAN Department of Manufacturing Engineering Annamalai University Department of Mechanical Engineering Birla Institute of Technology and Sciences

The hot deformation behaviour of 7075 aluminium alloy reinforced with 10%of SiC particles was studied by employing both"processing maps"and microstructural *** composite was characterized by employing optical microscope to evaluate the microstructural transformations and instability *** material investigated was deformed by compression in the temperature and strain rate ranges of 300-500℃and 0.001-1.0 s-1,*** deformation efficiency was calculated by strain rate sensitivity(m)values obtained by hot compression *** power dissipation efficiency and instability parameters were evaluated and processing maps were constructed for strain of *** optimum domains and instability zone were obtained for the *** optimum processing conditions are obtained in the strain rate range of 0.1-0.9 s-1and temperature range of 390-440 ℃with the efficiency of 30%.

关键词： hot deformation processing maps recrystallization flow instability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：