检索结果-南通市图书馆

Chemical characteristics and water stability evaluation of groundwater in the CkDu Zone of Sri Lanka

Journal of Environmental Sciences 2024年第12期146卷 67-80页

作者： Dazhou Hu Suresh Indika Madhubhashini Makehelwala COORAY Titus Liying Zhu Zhonghe Pang Hui Zhong Sujithra k.Weragoda k.b.S.n.Jinadasa Rohan Weerasooriya Yuansong Wei State key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Laboratory of Water Pollution Control Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Department of Applied Earth Sciences Uva Wellassa UniversityBadulla 90000Sri Lanka China-Sri Lanka Joint Research and demonstration Center for Water Technology Ministry of Water SupplyE.O.E.Pereira MawathaPeradeniya 24000Sri Lanka national Water Supply and Drainage board Katugastota 20800Sri Lanka Department of Civil Engineering Faculty of EngineeringUniversity of PeradeniyaPeradeniya 20400Sri Lanka national Institute of Fundamental Studies Kandy 20000Sri Lanka

Groundwater is the main source of drinking water for the rural population in the chronic kidney disease of unknown etiology(CkDu)zone of the north Central Province(nCP)in Sri *** this study,a total of 334 groundwater samples(311 dug wells,21 tube wells and 2 springs)during the wet season from two aquifers in the nCP were collected,and inves-tigated their chemical characteristics and evaluate their water quality,including ground-water chemistry,main ion sources,the corrosion and scaling potential of *** results showed that the two hydrochemical types of groundwater in the nCP were mainly of the Ca-HCO_(3),na·Ca-HCO_(3)types,with the main HCO_(3)−,na^(+)and Ca^(2+)ions in both types of groundwater originating from silicate and evaporite salt dissolution and influenced by alternating cation adsorption,while the presence of nO_(3)−was mainly ***-uation ofwater stability using namely Langelier saturation index(LSI),Ryznar stability index(RSI),Puckorius scaling index(PSI)and Larson-Skold index(LS),indicated that most ground-water presents corrosion potential and has corrosion behavior tendency of metals to some *** water quality of Polonnaruwa was better than that of Anuradhapura in the nCP,and when the groundwater was worse than the“good”grade,which must be properly treated before it is used as drinking water.

关键词： CkDu zone Rock weathering Cation alternating adsorption Water stability Water quality assessment

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

Micro-phytoplankton distribution and biomass in and around a channel-based fish farm: implications for sustainable aquaculture

引用

Acta Oceanologica Sinica 2014年第12期33卷 180-191页

作者： SADALLY S. b nAZURALLY n TALEb-HOSSEnkHAn n bHAGOOLI R Department of biosciences Faculty of Science University of Mauritius Department of Marine and Ocean Science Fisheries and Mariculture Faculty of Ocean Studies

Micro-phytoplankton density, genera composition, chlorophyllaconcentration, and physico-chemical pa-rameters were investigated at five stations （S1-near the coast; S2 and S4-at the edges of the aquaculture set-up; S3-in the center of the set-up; and S5-nearby patch of corals） in and around a coastal channel-based fish farm. The highest total micro-phytoplankton density （TPD）, including diatoms, dinoflagellates and cyanobacteria, was recorded at S3 （（6.28±2.00）×10^6 cells/L） followed by S4 （（5.87±2.81）×10^5 cells/L）, S1 （（4.92×10^5±8.70×10^4） cells/L）, S5 （（3.54×10^5±5.33×10^4） cells/L） and S2 （（2.60±1.14）×10^5cells/L）. Chlorophyll a and nutrient concentrations were highest at S3 and were positively correlated with TPD. Among the 35 genera documented in this study,Chaetoceros spp. was the dominant diatom whilePeridinium spp. was the most dominant dinoflagellate. Very low densities of toxic bloom-forming dinoflagellates were encountered during this study. These results suggest that occurrence of non-bloom densities of micro-phytoplankton, possibly due to the natural flushing of the existing lagoonal channel at the aquaculture site, yielded in little environmental impact and can represent an appropriate sustainable approach for future aquaculture de-velopment.

关键词： chlorophyll a micro-phytoplankton physico-chemical parameters sustainable aquaculture

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

Characteristics and Temperature Measurement of a non-Transferred Cascaded DC Plasma Torch

引用

Plasma Science and Technology 2010年第2期12卷 181-187页

作者： b.bORA n.AOMOA M.kAkATI Thermal Plasma Processed Materials Laboratory Centre of Plasma Physics Institute for Plasma Research Department of Physics Dibrugarh University

Dependence of the current-voltage characteristics of a non-transferred DC cascaded plasma torch used for nanoparticle synthesis, on the plasma current and the plasma argon gas flow rate are reported in this paper. The potential structure inside the torch and its dependence on the plasma current and gas flow rate are also investigated. The arc voltage is seen to exhibit negative characteristic for a current below 150 A and positive characteristic above that current value. The voltage drop near the electrodes is found to decrease with the increase in plasma current. 25~ of the total voltage is dropped near the cathode at a plasma current of 50 A and a argon plasma gas flow rate of 10 liter per minute （LPM）, and it decreases to 12% with the current increasing to 300 A, and to 17% with a gas flow rate of 25 LPM. The variation in the torch efficiency with the gas flow rate and plasma current is also reported. The efficiency of the torch is found to be between 36% and 48%. In addition, the plasma gas temperature at various positions of the reactor and for different currents and voltages are measured by calorimetric estimation with a heat balance technique.

关键词： DC plasma torch current voltage characteristics thermal efficiency temper- ature measurements

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

Influence of organic and inorganic properties of coal-shale on spontaneous combustion liability

引用

International Journal of Mining Science and Technology 2019年第6期29卷 851-857页

作者： M.Onifade b.Genc n.Wagner The School of Mining Engineering University of the WitwatersrandJohannesburg 2050South Africa Department of Geology University of JohannesburgJohannesburg 2092South Africa

Coal and coal-shale undergo low-temperature oxidation when exposed to air,potentially leading to spontaneous ***-shale found in association with coal seams vary considerably in their intrinsic properties and spontaneous combustion liability *** coal-shale samples collected from four different coal mines in Witbank Coalfield,South Africa,were experimentally *** influence of coal-shale intrinsic properties and spontaneous combustion liability indices(determined by the WitsEhac Index and the Wits-CT Index)were *** liability indices indicate relationships with the intrinsic factors and thus,identifying the major intrinsic factors affecting liability toward spontaneous combustion in these coal-shale *** XRF analysis indicated that the coal-shale samples are rich in Si O2,Al2O3 and Fe2O3,while the XRD showed that same coal-shale samples are generally dominated with kaolinite and *** coal-shale occurred in association with medium Rank C bituminous coal and contained varying proportion of *** Wits-Ehac Index was unable to reliably determine liability indices of some coal-shale samples,and hence the Wits-CT Index was *** results obtained from the characterisation tests may be used as a tool to predict the spontaneous combustion liability in carbonaceous material and may serve as a reference when comparing coal-shale from different coal mines.

关键词： Wits-Ehac Index Wits-CT Inde Witbank Coalfield and self-heating

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

Evidence and explanation for the involvement of the nucleus accumbens in pain processing

引用

neural Regeneration Research 2020年第4期15卷 597-605页

作者： Haley n.Harris Yuan b.Peng Department of Psychology University of Texas at Arlington

The nucleus accumbens(nAc)is a subcortical brain structure known primarily for its roles in pleasure,reward,and *** less focus on the nAc in pain research,it also plays a large role in the mediation of pain and is effective as a source of *** for this involvement lies in the nAc’s cortical connections,functions,pharmacology,and therapeutic *** nAc projects to and receives information from notable pain structures,such as the prefrontal cortex,anterior cingulate cortex,periaqueductal gray,habenula,thalamus,***,the nAc and other pain-modulating structures share functions involving opioid regulation and motivational and emotional processing,which each work beyond simply the rewarding experience of pain *** speaking,the nAc responds heavily to painful stimuli,due to its high density ofμopioid receptors and the activation of several different neurotransmitter systems in the nAc,such as opioids,dopamine,calcitonin gene-related peptide,γ-aminobutyric acid,glutamate,and substance P,each of which have been shown to elicit analgesic *** both preclinical and clinical models,deep brain stimulation of the nAc has elicited successful *** multi-functional nAc is important in motivational behavior,and the motivation for avoiding pain is just as important to survival as the motivation for seeking *** is possible,then,that the nAc must be involved in both pleasure and pain in order to help determine the motivational salience of positive and negative events.

关键词： analgesia circuitry deep brain stimulation nociception nucleus accumbens pain pain relief pain signaling reward striatum

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

Rift-associated ultramafic lamprophyre(damtjernite) from the middle part of the Lower Cretaceous(125 Ma) succession of kutch,northwestern India: Tectonomagmatic implications

引用

Geoscience Frontiers 2018年第6期9卷 1883-1902页

作者： Rohit PAnDey n.V.Chalapathi Rao Prashant Dhote Dinesh PAnDit A.k.Choudhary Samarendra Sahoo b.Lehmann Electron Probe Micro Analyzer Laboratory Department of Geology Centre of Advanced Study Banaras Hindu University bhumi Geoservices 1 & 2 Maa Bamleshwari Nagar Godhani Railway Institute Instrumentation Centre Indian Institute of Technology Mineral Resources Technical University of Clausthal

Mineralogical,geochemical and isotopic(Sr and nd) studies on the recently reported ca. 124 Ma'anorogenic lamproite' dyke from the Palanpur area, kutch seismogenic rift zone, northwestern India, are presented. We propose a new classification for the dyke as a damtjernite(ultramafic lamprophyre; UML)based on its porphyritic-panidiomorphic texture, abundance of phlogopite, presence of nepheline in the groundmass, and the composition of liquidus phases such as olivine, phlogopite, magnetite, and clinopyroxene(diopside). The Palanpur UML is primitive(Mg# =74-77),silica-undersaturated(SiO_2n nature, and is strikingly similar to the ～69 Ma UML dykes and sills of the Tethyan Indus suture zone, which are considered as the earliest yet known manifestations of the Deccan Large Igneous Province(LIP). bulk-rock(^(87)Sr/^(86)Sr)_i(0.70460-0.70461) and ε_(n)d(t)(+2.56 to-0.69) of the Palanpur UML signify derivation from a slightly depleted mantle source similar to that of asthenospheric magmas such as OIb. This is further attested to by the high incompatible trace element ratios(viz., La/ba, nb/U, nb/La and Ta/Yb) that are typical of plume-type magmas. However, the neoproterozoic T_(DM) depleted mantle nd model ages( ～655-919 Ma) also necessitate some involvement of a lithospheric mantle component in its genesis. High bulk-rock Fe_2 O_3~t and TiO_2 contents require the involvement of a fertile peridotitic mantle source, whereas high La/Yb(60-80) implies a control by residual garnet. Higher Rb/Sr and lower ba/Rb suggest phlogopite as a residual phase and high nb and lower La/Sm favour carbonatite, rather than silicate melt as metasomatising agent. Low degrees of partial melting of a primitive garnet lherzolite mantle can account for the observed REE patterns in the Palanpur UML. The Palanpur UML shares a temporal similarity to the kerguelen plume-derived Rajmahal basalts and associated alkaline rocks from the eastern India. The tectonomagmatic

关键词： Tectonomagmatism Cretaceous Ultramafic lamprophyre Rift kutch India

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

Effect of temperature on the intensity and carrier lifetime of an AlGaAs based red light emitting diode

引用

Journal of Semiconductors 2013年第9期34卷 1-5页

作者： P.Dalapati n.b.Manik A.n.basu Condensed Matter Physics Research Center Department of PhysicsJadavpur University

The influence of temperature on the intensity of light emitted by as well as the carrier life time r of a standard A1GaAs based light emitting diode has been investigated in the temperature range from 345 to 136 k. The open-circuit voltage decay （OCVD） technique has been used for measured the carrier lifetime. Our experimental results reveal a 16% average increase in intensity and a 163.482-19.765 ns variation in carrier lifetime in the above temperature range. Further, theoretical and experimental analysis show that for negligible carrier density the intensity is inversely proportional to carrier lifetime for this sample.

关键词： LED low temperature intensity ideality factor carrier lifetime

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

Influence of temperature on tunneling-enhanced recombination in Si based p–i–n photodiodes

引用

Journal of Semiconductors 2014年第8期35卷 10-14页

作者： P.Dalapati n.b.Manik A.n.basu Condensed Matter Physics Research Center Department of Physics Jadavpur University

We investigate the dominant dark current transport mechanism in Si based p-i-n photodiodes, namely, bPW 21R, SFH 205FA and bPX 61 photodiodes in the temperature range of 350 to 139 k. The forward current- voltage characteristics of these photodiodes are explained via the tunneling enhanced recombination model, which gives a quantitative description of the electronic mechanism in the p-i-n junction photodiodes. The observed tem- perature dependence of the saturation current and the diode ideality factor of these devices agree well with theo- retical predictions; the analysis also indicates the importance of doping for enhancement of tunneling. The present study will be helpful in applying the devices at low temperature ambience.

关键词： photodiode low temperature ideality factor reverse saturation current tunneling energy

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

Effects of rainwater harvesting on herbage diversity and productivity in degraded Aravalli hills in western India

引用

Journal of Forestry Research 2011年第3期22卷 329-340页

作者： G. Singh G.R. Choadhary b. Ram n.k. Limba Division of Forest Ecology Arid Forest Research Institute New Pali Road Jodhpur-342005 India

Over-exploitation and rural growth have severely damaged native vegetations of Aravalli hills in Rajasthan, India. This study was conducted to evaluate the effects of different restoration practices （i.e., rainwater harvesting （RWH） and planting of tree seedlings） on improve- ment in soil water and nutrients and growth and biomass of herbaceous vegetation. Contour trench （CT）, Gradonie （G）, box trench （bT）, V-ditch （VD） and a control were imposed on 75 plots （each of 700 m 2 ） in natural slope gradient defined as 10%, 10% 20% and 20% slopes in 2005. Each plot had three micro-sites of 1-m 2 at up （USP）, middle （MSP） and lower （LSP） part of the plot for observation in 2008. The existed gradient （due to soil texture and topographic features） of soil pH, EC, SOC, nH 4 - n, nO 3 -n and PO 4 -P in June 2005 between 20% to 10% slopes were decreased in 2008 after applying RWH techniques. Such improvement in soil status promoted vegetation growth and biomass in higher slope gra- dients. Soil water, species diversity and herbage biomass increased from USP to LSP, and RWH techniques had positive role in improving SOC, nutrients, vegetation population, evenness and growth at MSP. Despite of lowest SWC, regular rain and greater soil water usage enhanced green and dry herbage biomasses in 10% 20% and 20% slopes, compared with 10% slope. The highest diversity in CT treatment was related to herbage biomass, which was enhanced further by highest concentrations of SOC and PO 4 -P. Further, CT treatment was found to be the best treat- ment in minimizing biomass variance in different slopes. Conclusively, soil texture and topographic features controlled soil water and nutrients availability. Rainwater harvesting techniques increased soil water storage and nutrient retention and also enhanced vegetation status and biomass by minimizing the effects of hillslopes. Thus depending upon the site conditions, suitable RWH technique could be adopted to increase herb- age biomass while rehabilit

关键词： herbage growth and biomass hillslopes soil nutrients soil water dynamics vegetation diversity

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

Influence of the safety factor profile on the particle and heat transport in the Globus-M spherical tokamak

引用

Plasma Science and Technology 2019年第11期21卷 1-6页

作者： A YU TELnOVA G S kURSkIEV E O kISELEV n n bAkHAREV V k GUSEV n A kHROMOV S YU MEDVEDEV V b MIInAEV I V MIROSHnIkOV M I PATROV Yu V PETROV n V SAkHAROV A D SLADkOMEDOVA P b SHCHEGOLEV V V SOLOkHA V A TOkAREV S YU TOLSTYAkOV E A TUkHMEnEVA Ioffe Institute Saint-Petersburg 194021Russia keldysh Institute Russian Academy of SciencesMoscow 125047Russia nRC'kurchatov Institute’ Moscow 123098Russia

The advanced tokamak scenario is a promising operation scenario for ITER and fusion neutron *** this scenario the minimum value of the safety factor in the center of the plasma exceeds *** the compact spherical tokamak Globus-M,the formation of such conditions is possible with neutral beam injection at the current ramp-up *** to the slower diffusion of current inside the plasma,a zone is formed with reduced heat and particle transport across the magnetic field,which affects the temperature and density profiles of the *** leads to the peaked density profile formation and improvement of the energy confinement *** achieve a high fraction of the bootstrap current,it is necessary to increase the plasma *** the same time,the maximum allowable pressure is limited to the normalized beta limit.

关键词： advanced tokamak mode transport analysis internal transport barriers

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：