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ch.nese chemical Letters 2010年第4期21卷 421-425页

作者： santosh S.Katkar Pravinkumar H.Mohite Lakshman S.Gadekar Kaluram n.Vidhate Machhindra K.Lande Department of chemistry Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad 431004MSIndia chemical Engineering and Process Development Division National Chemical LaboratoryPune 411008MSIndia

A cheap and recyclable ZnO-beta zeolite was used as catalyst for the synthesis of benzothiazole *** method provides several advantages such as environmental friendliness,short reaction times,high yields,simple work-up... 详细信息

关键词： ZnO-beta zeolite Benzothiazole Cyclocondensation Heterogeneous catalyst

MOS Capacitance-Voltage characteristics:Ⅳ.Trapping Capacitance from 3-charge-State Impurities

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Journal of Semiconductors 2012年第1期33卷 1-19页

作者： Jie Binbin sah chihtang Department of Physics Xiamen University Xiamen 361005China CTsah Associates GainesvilleFlorida 32605USA

Metal-Oxide-Semiconductor Capacitance-Voltage （MOSCV） characteristics containing giant carrier trapping capacitances from 3-charge-state or 2-energy-level impurities are presented for not-doped, n-doped, p- doped and compensated silicon containing the double-donor sulfur and iron, the double-acceptor zinc, and the amphoteric or one-donor and one-acceptor gold and silver impurities. These impurities provide giant trapping ca- pacitances at trapping energies from 200 to 800 meV （50 to 200 THz and 6 to 1.5 μm）, which suggest potential sub-millimeter, far-infrared and spin electronics applications.

关键词： multiple charge states trapping capacitance dopant impurity

Structural Tuning of Low Band Gap Intermolecular Push/Pull Side-chain Polymers for Organic Photovoltaic Applications

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ch.nese Journal of Polymer Science 2017年第9期35卷 1073-1085页

作者： Ansuman nayak P.S. Rama Sreekanth santosh Kumar sahu Duryodhan sahu Department of chemistry National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008 Department of chemistry Gandhi Institute of Engineering and Technology Gunpur Odisha India Department of Mech.nical Engineering National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008

A series of novel low band gap donor-acceptor （D-A） type organic co-polymers （BT-F-TPA, BT-CZ-TPA and BT-SI-TPA） consisting of electron-deficient acceptor blocks both in main chains （M1） and at the pendant （M2） were polymerized with different electron rich donor （M3-M5） blocks, i.e., 9,9-dihexyl-9H-fluorene, n-alkyl-2,7-carbazole, and 2,6-dithinosilole, respectively, via Suzuki method. These polymers exhibited relatively low band gaps （1.65-1.88 eV） and broad absorption ranges （680-740 nm）. Bulk heterojunction （BHJ） solar cells incorporating these polymers as electron donors, blended with [6,6]-phenyl-C61-butyric acid methyl ester （PC61BM） or [6,6]-phenyl-Cvl-butyric acid methyl ester （PC71BM） as electron-acceptors in different weight ratios were fabricated and tested under 100 mW/cm2 of AM 1.5 with white-light illumination. The photovoltaic device containing donor BT-SI-TPA and acceptor PC71BM in 1：2 weight ratio showed the best power conversion efficiency （PCE） value of 1.88%, with open circuit voltage （Voc） = 0.75 V, short circuit current density （Jsc） = 7.60 mA/cm2, and fill factor （FF） = 33.0%.

关键词： Polymer solar cells Low band gap Conducting polymers charge transfer Donor-acceptor Bulk heterojunctionsolar cell

Effect of disturbance on biomass,production and carbon dynamics in moist tropical forest of eastern nepal

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Forest Ecosystems 2016年第3期3卷 221-230页

作者： Tilak prasad Gautam Tej narayan Mandal Department of Botany Mahendra Morang Adarsha Multiple CampusTribhuvan University Department of Botany Post Graduate Campus Tribhuvan University

Background： Forest biomass is helpful to assess its productivity and carbon （C） sequestration capacity. Several disturbance activities in tropical forests have reduced the biomass and net primary production （nPP） leading to climate ch.nge. Therefore, an accurateestimation of forest biomass and C cycling in context of disturbances is required for implementing REDD （Reducing Emissions from Deforestation and Forest Degradation） policy. Methods： Biomass and nPP of trees and shrubs were estimated by using allometric equations while herbaceous biomass was estimated by harvest method. Fine root biomass was determined from soil monolith. The C stock in vegetation was calculated by multiplying C concentration to dry weight. Results： Total stand biomass （***-1） in undisturbed forest stand （US） was 960.4 while in disturbed forest stand （DS） it was 449.1. The biomass （***-1） of trees, shrubs and herbs in US was 948.0, 4.4 and 1.4, respectively, while in DS they were 438.4, 6.1 and 1.2, respectively. Total nPP （***-1） was 26.58 （equivalent to 12.26 Mg ***-1） in US and 14.91 （6.88 Mg ***-1） in DS. Total C input into soil through litter plus root turnover was 6.78 and 3.35 ***-1 in US and DS, respectively. Conclusions： Several disturbance activities resulted in the significant loss in stand biomass （53 %）, nPP （44 %）, and C sequestration capacity of tropical forest vegetation is far greater than that returned to the soil n eastern nepal. The net uptake of carbon by the by the turnover of fine root and litter. Therefore, both stands of present forest act as carbon accumulating systems. Moreover, disturbance reflects higher C emissions which can be reduced by better management.

关键词： Tropical forest Disturbance Biomass Production Carbon cycling nepa

An Inventory of the Above Ground Biomass in the Mau Forest Ecosystem,Kenya

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Open Journal of Ecology 2014年第10期4卷 619-627页

作者： Mwangi James Kinyanjui Petri Latva-Kayra prasad sah Bhuwneshwar Patrick Kariuki Alfred Gichu Kepha Wamichwe Department of Resource Surveys and Remote Sensing NairobiKenya Arbonaut Oy Ltd. HelsinkiFinland PASCO Corporation TokyoJapan Kenya Forest Service NairobiKenya natural Resource Information&Technology Ltd. NairobiKenya

Biomass assessment of the Mau Forest Ecosystem (MFE) was done as part of Kenya’s greenhouse gas inventory. Trans Mara and Mount Londiani forest blocks representing extremes of vegetation types in the MFE were selected for ground data. Based on canopy closure, four forest strata were identified as very dense, moderately dense, open and bamboo. In each stratum, 5 clusters each with 4 plots measuring 30 m × 30 m were located. Big trees (D1.3 ≥ 10 cm) were measured per species for diameter at breast height (D1.3) in the whole plot while height was measured for every 5th tree. Poles (10 cm > D1.3 ≤ 5) were measured for D1.3 in a 10 × 10 m concentric sub plot. Saplings (5 cm > D1.3;ht ≥ 1.5 m) and seedlings (ht numerated per species within 5 × 5 m and 2 × 2 m concentric sub plots, respectively. Data were recorded in a Personal Digital Assistant (PDA) and quality checked with Open Foris Collect software. Allometric equations that have been used for similar vegetation in Kenya were used to relate D1.3 and height with biomass. The tree data were uploaded to ArboWebForest (AWF) cloud-service and using the AWF-SIMO calculation tool, average values of diameter, height, and biomass were calculated for each plot. The data were generalised to cover all areas for each block using the Sparse Bayesian linear regression process on the vegetation characteristics with 10 m resolution ALOS-AVnIR-2 images of the MFE. AnOVA was used to compare biomass generated from several allometric equations. Results show that the average biomass of the MFE was 236 Mg·ha1. Degradation that converts dense forests into open and moderately dense forests contributed to a biomass loss of 228 Mg·ha1 and 194 Mg·ha1 respectively. Four allometric equations gave no significant difference (P n biomass for the 80 plots implying that costly processes of developing new equations may not improve accuracy. The study offers a learning lesson in Kenya’s forest inventory processes and the biomass v

关键词： Forest Biomass Inventory

Uniform and graded bed-load sediment transport in a degrading ch.nnel with non-equilibrium conditions

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International Journal of Sediment Research 2020年第2期35卷 115-124页

作者： Khabat Khosravi Amir H.n.chegini James R.Cooper prasad Daggupati Andrew Binns Luca Mao School of Engineering University of Guelph School of the Built Environment Heriot-Watt University Department of Geography and Planning School of Environmental SciencesUniversity of Liverpool Department of Geography University of Lincoln

Bed-load transport plays a critical role in river morphological ch.nge and has an important impact on river *** there is good understanding of the role of the variation of river bed grain size on transport dynamics in equilibrium conditions,much less is understood for non-equilibrium conditions when the ch.nnel is either aggrading or *** particular,the relative role of different grain sizes in the promotion and hindering of the transport of coarse and fine fractions in a degrading ch.nnel has yet to be *** current study attempts to provide new understanding through a series of flume experiments done using uniform and graded sediment *** experiments revealed coarser grain-size fractions for a poorly-sorted sediment,relative to uniform-sized sediment,reduced the transport of finer grains and finer fractions enhanced the transport of coarse *** hinderingpromotion effect,caused by relative hiding and exposure of finer and coarse fractions,increased with bed slope and decreased with relative *** particular,as relative submergence increased,the graded fractions tended towards behaving more like their unifo rm-sized ***,the bed-load parameter of the graded fractions increased more with a rise in bed slope than observed for the uniformsized *** results revealed,for degrading ch.nnel conditions,such as downstream of a dam,bed-load equations developed for uniform bed sediment are inappropriate for use in natural river systems,particularly in mountain ***,ch.nges in river bed composition due to activities that enhance the input of hill-slope sediment,such as fire,logging,and agricultural development,are likely to cause significant ch.nges in river morphology.

关键词： Graded sediment Exposure Hiding Flume experiments non-equilibrium

Deep learning model for estimating the mech.nical properties of concrete containing silica fume exposed to high temperatures

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1316-1330页

作者： Harun TAnYILDIZI Abdulkadir SEnGUR Yaman AKBULUT Murat sahtna Faculty of Technology Department of Civil EngineeringFirat UniversityElazig 23100Turkey Faculty of Technology Department of Electrical-Electronics EngineeringFir at UniversityElazig 23100Turkey

In this study,the deep learning models for estimating the mech.nical properties of concrete containing silica fume subjected to high temperatures were *** fume was used at concentrations of 0%,5%,10%,and 20%.Cube specimens(100 mm×100 mm×100 mm)were prepared for testing the compressive strength and ultrasonic pulse *** were cured at 20℃zb2℃ in a standard cure for 7,28,and 90 *** curing,they were subjected to temperatures of 20℃,200℃,400℃,600℃,and 800℃.Two well-known deep learning approaches,i.e.,stacked autoencoders and long short-term memory(LSTM)networks,were used for forecasting the compressive strength and ultrasonic pulse velocity of concrete containing silica fume subjected to high *** forecasting experiments were carried out using MATLAB deep learning and neural network tools,*** statistical measures were used to validate the prediction performances of both the *** study found that the LSTM network achieved better results than the stacked *** addition,this study found that deep learning,which has a very good prediction ability with little experimental data,was a convenient method for civil engineering.

关键词： concrete high temperature strength properties deep learning stacked auto-encoders LSTM network

Synthesis of n1-3-{（4-Substituted aryl-3-chloro-2-oxo- azetidine）-iminocarbamyl}-propyl-6-nitroindazole Derivatives and Their Biological Significance

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ch.nese Journal of chemistry 2011年第8期29卷 1745-1752页

作者： Samadhiya, Pushkal Sharma, Ritu Srivastava, santosh K. Srivastava, Savitri D. Synthetic Organic chemistry Laboratory Department of Chemistry Dr. H. S. Gour University (A Central Univer- sity) Sagar M.P. 470003 India

Synthesis of n1-3-{（4-substitute daryl-3-chloro-2-oxo-azetidine）-iminocarbamyl}-propyl-6-nitroindazole 4a-- 4s was conducted by a conventional method. All the compounds were synthesized and characterized by IR, 1H nMR, 13C nMR, FAB-Mass techniques and chemical methods. All the final synthesized compounds were evaluated for their antimicrobial activity and antitubercular activity with MIC values against some selected microorganisms.

关键词： synthesis 6-nitroindazole 2-azetidinone biological activity

Meteorite impact craters as hotspots for mineral resources and energy fuels:A global review

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Energy Geoscience 2022年第2期3卷 136-146页

作者： S.James Saranya R.ch.ndran M.santosh A.P.Pradeepkumar M.n.Praveen K.S Sajinkumar s sajinkumar 1 2department of geologyuniversity of keralathiruvananthapuram695581keralaindia school of earth science and resources china university of geosciencesbeijing100083china department of earth sciences university of adelaidesa5005australia geological survey of india bengaluru560111india department of geological and mining engineering and sciences michigan technological universityhoughton49931miusa

The ever-increasing recovery rate of natural resources from terrestrial impact craters over the last fewdecades across the globe offers new avenues for further exploration of mineral and hydrocarbon resources in such *** of today,60 of the 208 terrestrial craters have been identified to host diverseresources such as hydrocarbons,metals and construction *** potential of craters as plausibleresource contributors to the energy sector is therefore,worthy of consideration,as 42(70%)of the 60craters host energy resources such as oil,gas,coal,uranium,mercury,critical and major minerals as wellas hydropower *** others,19 craters are of well-developed hydrocarbon *** associated with craters are also classified similar to other mineral resources such as progenetic,syngenetic and epigenetic *** these,the progenetic and syngenetic mineralization are confinedto the early and late excavation stage of impact crater evolution,respectively,whereas epigenetic deposits are formed during and after the modification stage of crater ***,progenetic andsyngenetic mineral deposits(like Fe,ni,Pb,Zn and Cu)associated with craters are formed as a directresult of the impact event,whereas epigenetic deposits(***)are hosted by the impactstructure and result from post-impact *** the progenetic and syngenetic deposits,the shockwave induced fracturing and melting aid the formation of deposits,whereas in the epigenetic deposits,the highly fractured lithostratigraphic units of higher porosity and permeability,like the centralelevated area(CEA)or the rim,act as *** this review,we provide a holistic view of the mineral andenergy resources associated with impact craters,and use some of the remote sensing techniques toidentify the mineral deposits as supplemented by a schematic model of the types of deposits formedduring cratering process.

关键词： Meteorite impact crater Progenetic deposit Syngenetic deposit Epigenetic deposit Mineralization Hydrocarbon Petroleum Exploration

choice of Beef Herd Adaptation Strategy on Canadian Prairie Mixed Farms Under Extreme Climate Events

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Sociology Study 2016年第3期6卷 147-163页

作者： santosh Poudel Surendra n. Kulshreshtha University of Saskatchewan Saskatoon Canada

Economic impact of climate extremes on beef operation is expected to be significant due to its direct impact on feed production. Impact of such events on farm management and longer term farm financial situation is relatively unstudied in the Canadian Prairie. This study compared three alternative beef herd management strategies in dealing with climate extreme events under reference climate scenario of 1971-2000 and the future scenario of 2041-2070. The study used farm simulation model that integrated the model of cattle herd simulation, pasture model, crop simulation model combined with models of economic decisions. Purchasing feed and maintaining herd size is preferred option in dealing with drought ch.nges in management such as early weaning combined with limit feeding strategies reduce the feed demand and also reduce the financial burden during the years of extreme event, but it has severe negative consequences on amount of slaughter cattle sold. Cull herd strategy not only reduces feed demand but also increases income from sell of herd during the year/s of extreme event, but it severely impacts the farm＇s long term output supply potential. However, expansion of existing agriculture risk management policy to cover climate risk in beef production is necessary to support farmers in the year/s to extreme events.

关键词： Climate extreme adaptation strategies economic impact