检索结果-南通市图书馆

Assessment of land use change and its effect on soil carbon stock using multitemporal satellite data in semiarid region of Rajasthan, India

在线全文

学校读者我要写书评

暂无评论

Ecological Processes 2019年第1期8卷 513-529页

作者： Garima Sharma L.k.Sharma k.c.Sharma Department of Environmental Science Central University of RajasthanNH-8BandarsindriRajasthan 305817India M.D.S.University AjmerRajasthanIndia.

Background:Land use change plays a vital role in global carbon *** land use change impact on soil carbon stock is crucial for implementing land use management to increase carbon stock and reducing carbon ***,the objective of our study was to determine land use change and to assess its effect on soil carbon stock in semi-arid part of Rajasthan,*** temporal satellite data of Pushkar valley region of Rajasthan acquired on 1993,2003,and 2014 were analyzed to assess land use *** trading of land use was depicted *** organic carbon(SOc)stock was calculated for soil to a depth of 30 cm in each land use type in 2014 using field data *** SOc stock for previous years was estimated using stock change *** effect of land use change on SOc stock was determined by calculating change in SOc stock(t/ha)by deducting the base-year SOc stock from the final year stock of a particular land use ***:The total area under agricultural lands was increased by 32.14%while that under forest was decreased by 23.14%during the time period of 1993–*** land use change shows that in both the periods(1993–2003 and 2003–2014),7%of forest area was converted to agricultural land and about 15%changes occurred among agricultural *** 1993–2003,changes among agricultural land led to maximum loss of soil carbon,i.e.,4.88 Mt c and during 2003–2014,conversion of forest to agricultural land led to loss in 3.16 Mt ***:There was a continuous decrease in forest area and increase in cultivated area in each time *** use change led to alteration in carbon equity in soil due to change or loss in ***,we can conclude that the internal trading of land use area during the 10-year period(1993–2003)led to net loss of SOc stock by 8.29 Mt ***,land use change during 11-year period(2003–2014)caused net loss of SOc by 2.76 Mt *** should be made to implement proper land

关键词： Multitemporal satellite data Land use change dynamics Internal trading of land use SOc stock,Stock change factor change in SOc pool Land use management

Litter production, decomposition and nutrient mineralization dynamics of Ochlandra setigera: A rare bamboo species of Nilgiri Biosphere Reserve, India

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

Journal of Forestry Research 2014年第3期25卷 579-584页

作者： kuruvilla Thomas c.M. Jijeesh k.k. Seethalakshmi SFM Division Kerala Forest Research Institute Dept of Silviculture & Agroforestry College of Forestry

Litter production, decomposition and nutrient release dynam-ics of Ochlandra setigera, a rare endemic bamboo species of Nilgiri biosphere were studied during 2011-2012 using the standard litter bag technique. Annual litter production was 1.981 t？ha-1 and was continuous throughout the year with monthly variations. Litterfall followed a tri-phasic pattern with two major peaks in November, 2011 and January, 2012 and a minor peak in July, 2011. The rate of decomposition in O. setigera was a good fit to the exponential decay model of Olson （1963）. Litter quality and climatic conditions of the study site （maximum tem-perature, monthly rainfall and relative humidity） influenced the rate of decomposition. Nutrient release from the decomposing litter mass was in rank order N=Mg＆gt;k=ca＆gt;P. Nutrient release from litter was con-tinuous and it was in synchrony with growth of new culms. Study of litter dynamics is needed before introduction of a bamboo species into degraded or marginal lands or Agroforestry systems.

关键词： Ochlandra setigera litter fall litter decomposition nutrientrelease decomposition rate

Effect of promoters on dynamics of gas-solid fluidized bed——Statistical and ANN approaches

在线全文

学校读者我要写书评

暂无评论

china Particuology 2007年第6期5卷 401-407页

作者： Y.k. Mohanty k.c. Biswal G.k. Roy B.P. Mohanty Department of chemical Engineering GIET Gunupur 765 022 Rayagada Orissa India Department of chemical Engineering NIT Rourkela 769008 Orissa India

In this study, a bubbling fluidized bed column, 99 mm in inside diameter and 960 mm in height, was used to investigate the effect of rod and disc promoters on fluctuation and expansion ratios. Factorial design （statistical approach） and artificial neural network （ANN） models were developed to predict the fluctuation and expansion ratios in this gas-solid fluidized bed with varying gas flow rates, bed heights, particle sizes and densities. The fluctuation and expansion predicted using these statistical and ANN models, for beds with and without promoters, were found to agree well with corresponding experiments. The statistical model was found to be superior to the ANN model due to its ability to take into account both individual and interactive effects. The rod promoters were found to be more effective in reducing bed fluctuation, and in increasing bed expansion at high gas mass velocities.

关键词： Gas-solid fluidized bed Fluctuation ratio Expansion ratio Promoter Factorial design Artificial neural network

Differential-algebraic cryptanalysis of reduced-round of Serpent-256

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2010年第3期53卷 546-556页

作者： HUI Lucas c.k. Department of computer Science and Information Systems The University of Hong Kong

Differential cryptanalysis is a general cryptanalytic tool that makes use of diFFerentials over some rounds of a cipher, combined with some key bit guesses of one or two rounds. This paper introduces a new cryptanalysis strategy of block ciphers named differential-algebraic cryptanalysis. The idea of differential-algebraic cryptanalysis is to find a differential with high probability and build the multivariable system equations for the last few rounds. The subkey values of the last few rounds can be obtained by filtering the solutions of system equations instead of guessing all possible subkey values. We use the differential-algebraic cryptanalysis to break 8-round Serpent-256. Our attack can recover the 256-bit key with 283 chosen plaintexts, 2180.4 8-round Serpent- 256 encryptions and 2176.7 bytes memory. compared with the previous differential cryptanalysis results, both the data complexity and the time complexity are reduced, but the memory requirements are increased. The time complexity and the memory requirements are very close, and a time-memory tradeoff is exploited.

关键词： differential-algebraic cryptanalysis Serpent solving equations

Electroosmotic oscillatory flow of micropolar fluid in microchannels:application to dynamics of blood flow in microfluidic devices

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 749-766页

作者： J.c.MISRA S.cHANDRA G.c.SHIT P.k.kUNDU Department of Mathematics Institute of Technical Education and ResearchSiksha O Anusandhan University Department of Mathematics Jadavpur University

The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss＇s law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices.

关键词： blood flow electrohydrodynamic effect microfluidics channel flow

Rare cause of ileus in the mesenteric cavity of terminal ileum:A report of three cases

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2006年第33期12卷 5422-5423页

作者： A Tekin F Aksoy c Vatansev T kücükkartallar Department of General Surgery Selcuk University Meram Medical Faculty Akyoku■ KonyaTurkey

Internal herniation is one of the rare reasons of intestineclog, which is hard to diagnose and usually needs anurgent surgical treatment. We report 3 patients withinternal herniation in the mesenteric cavity of theterminal ileum. Besides intestinal congestion, they alsohad peritoneal irritation. Laparotomy revealed thatherniation caused disorder in nutrition of the intestineand necrosis. The patients underwent subtotal smallintestine resection and were discharged 10, 12 and 14 dafter operation.

关键词： Intestinal herniation Ileus Therapy

Influence of Sputtering Power on the Structure and Electrical Properties of Bi_2Fe_4O_9 Thin Films

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

Acta Metallurgica Sinica(English Letters) 2017年第7期30卷 650-658页

作者： M.Santhiya k.S.Pugazhvadivu k.Tamilarasan c.Rangasami Thin Film Research Laboratory Department of PhysicsKongu Engineering CollegePerundurai 638 052India

Bismuth ferrite（Bi_2Fe_4O_9） thin films were grown on p-type Si（100） substrate by radio-frequency magnetron sputtering at 873 k. X-ray diffraction, field emission scanning electron microscopy and Raman spectroscopy studies revealed that the grown films have single-phase polycrystalline nature and are crystallized in orthorhombic structure. The grain size of the grown thin films was found to increase（56–130 nm） with sputtering power. Atomic force microscopy images clearly illustrated that the grown thin films have smooth surface. Energy-dispersive X-ray analysis revealed the presence of Bi, Fe and O elements with desired ratio and also the absence of impurities in the grown films. Analysis of ferroelectric hysteresis loops revealed that the remanent polarization and coercive field increase with the increase in sputtering power. Vicker＇s hardness analysis showed that the hardness of films strongly depends on the grain size and film thickness, which are mainly determined by the sputtering power. The above observations revealed that Bi_2Fe_4O_9 thin film deposited at higher sputtering power has good crystallinity and shows better electrical properties.

关键词： Bi_2Fe_4O_9 Thin films Ferroelectric Sputtering X-ray diffraction Hardness

Ethnobotanical Study towards conservation of Medicinal and Aromatic Plants in Upper catchments of Dhauli Ganga in the central Himalaya

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2012年第2期9卷 286-296页

作者： L.S.kANDARI P.c.PHONDANI k.c.PAYAL k.S.RAO R.k.MAIkHURI School of Natural Resources Management and Environmental Sciences College of Agriculture and Environmental SciencesHaramaya University G.B.Pant Institute of Himalayan Environment&Development Department of Botany University of Delhi

The present study broadly focused on medicinal plant species collected from wild by the villagers for different purposes in the upper catchment of Dhauli Ganga in Nanda Devi Biosphere Reserve(NDBR),in the central Himalaya.A schedule based survey was conducted during the years 2003-2005 in 15 villages of chamoli district part of the *** was collected from collectors, vaidya(medicine man)and those dealing with domestication and marketing of the medicinal plants. The aim of the study was to understand the prioritiesed medicinal plants,their mode of collection and document their ethnobotanical uses by the Bhotiya tribal communities,in this world heritage site. During the survey,50 medicinal plants belonging to 31 families and 44 genera were *** of these,70% were harvested from the wild,22% were cultivated and 8% were cultivated as well as wild *** the cultivated species,8% were found growing in the kitchen gardens and 14%in the agricultural ***,42%of the plants had their roots and rhizomes used followed by leaves (26%),seeds(10%),seed and leaf(8%),bark and whole plant(6%)and flower(1%).Most plants were reported to be used for rheumatism(16),followed by stomach disorder(14),cold and cough(11),and jaundice(9).Thirty three plants species were reported to have more than one therapeutic uses,while 17 species were reported to be used against single *** distance of villages from road head was one of the factors contributing to the decline in the medicinal plant population in their natural habitats. The availability of medicinal plants increased with increase in distance from road head and also the peoples'dependence on *** of the traditional knowledge will help in conservation of knowledge and also opportunity for using it for future training and *** result of this study will help in promoting sustainable cultivation and implementation in conservation protocol of those species,which are in the verge of exti

关键词： conservation strategy Ethnobotany Medicinal plants Traditional communities central Himalaya

Effect of laccase from Trametes versicolor on the oxidative stability of edible vegetable oils

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2019年第4期8卷 356-361页

作者： G.k.Guerberoff c.c.camusso cátedra de Química Orgánica Facultad de Ciencias AgropecuariasUniversidad Nacional de CórdobaAv.Valparaíso s/nCórdoba CapitalArgentina

The increasing demand of natural food from consumers has limited the use of traditional methods to control the oxidation of lipids,such as synthetic antioxidants and ***,it has been reported that the use of enzymes is efficient to eliminate dissolved oxygen in foods such as vegetable *** is a polyphenol oxidase and the reduction of oxygen to water is accompanied by the oxidation,typically,of a phenolic *** have become important,industrially relevant enzymes that can be used for a number of diverse applications such waste detoxification,textile dye transformation,food technologic uses,biosensor and analytical applications,bioethanol production,among *** target of this study was to evaluate the effect of laccase enzyme from Trametes versicolor,on the oxidative stability of sesame,chia,peanut and sunflower oils,measured through the peroxide value(PV)and conjugated dienes(k232)and trienes(k270).The samples of oil with laccase showed higher PV,k232 and k270 than their corresponding controls,under the conditions evaluated(room temperature and 60◦c).The results suggest that fungal laccase has an unexpected pro-oxidant effect on vegetable oils,possibly promoted by products derived from the oxidation of phenols by enzymatic action.

关键词： Laccase Trametes versicolor Vegetable oils Oxidative stability