检索结果-南通市图书馆

Experimental Study of Parameters of a Plasma Antenna

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2010年第5期12卷 592-600页

作者： Rajneesh KUMAR Dhiraj bora Institute for Plasma Research ITER Organisation

A plasma column excited by a surface wave can act as a plasma antenna. Experiments are carried out to study the current and conductivity distributions, field, power patterns, directivity and efficiency of such a plasma antenna. In addition, an equivalent metallic copper antenna is built up and its antenna parameters are compared with that of the plasma antenna. Our findings indicate that the power content in the harmonics of the plasma antenna is more prominent as compared to the copper antenna （which only generates a fundamental frequency）. However, the power patterns for both antennae are quite similar. To provide a more qualitative understanding regarding the generation of harmonics in the field of the plasma antenna, a bi-spectral analysis is performed to study the nonlinear interactions in the current fluctuations. Some specific features of the plasma antenna are investigated in our study, which may enhance the application prospect of the plasma antenna with respect to the conventional metallic antenna.

关键词： plasma column antenna parameters plasma antenna metallic copper antenna non-linear interactions

Solar photocatalytic pathogenic disinfection:Fundamentals to state-of-the-art

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

Water Science and Engineering 2023年第2期16卷 132-142页

作者： Leena V.bora Department of Chemical Engineering Institute of TechnologyNirma UniversitySarkhej-Gandhinagar HighwayAhmedabad 382481India

It is necessary to treat pathogen-infected water before its *** conventionally used treatment methods,solar photocatalysis has gained considerable momentum owing to its operational simplicity and capacity to use freely and abundantly available solar *** article systematically reviewed the disinfection of water with *** addressed the concerns of microbial infection of water and the fundamentals behind its treatment with *** presented an in-depth description of pathogenic deactivation with powerful reactive oxygen *** emphasis was given to process intensification as it is an attractive technique that provides multifunctionality and/or equipment *** reactor design regarding mobilised/immobilised photocatalysts and compound parabolic concentrators were ***,key parameters governing photoperformance,corresponding trade-offs,and the need for their optimisation were ***,this article is a single point of reference for researchers,environmentalists,and industrialists who address the ever-severing challenge of providing clean water whilst also maintaining energy sustainability.

关键词： Water Solar light Photocatalysis Pathogen E.coli Intensification Photoreactor Disinfection

Development of yield forecast model using multiple regression analysis and impact of climatic parameters on spring wheat

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2019年第4期12卷 110-115页

作者： Purbasha Mistry Ganesh bora Natural Resources Management North Dakota State UniversityFargoND 58102USA Agricultural and Biological Engineering Department Mississippi State UniversityStarkvilleMS 39762USA

Understanding the impacts of climate change in agriculture is important to ensure optimal and continuous crop *** agricultural sector plays a significant role in the economy of Upper Midwestern states in the USA,especially that of North Dakota(ND).Spring wheat contributes most of the wheat production in ND,which is a major producer of wheat in the *** study focuses on assessing possible impacts of three climate variables on spring wheat yield in ND by building a regression ***-five years of field data were collected and the trend of average minimum temperature along with average maximum temperature,average precipitation,and spring wheat yield was analyzed using Mann-Kendall *** study area was divided into 9 divisions based on physical *** minimum temperature plays an important role in the region as it impacts the physiological development of the *** trend was noticed for 6 divisions for average minimum temperature and average precipitation during growing *** and Southeast division showed the strongest increasing trend for average minimum temperature and average precipitation,***-central division had the most decreasing trend for average maximum temperature.A significant relationship was established between spring wheat yield and climatic parameters as the p-value is lower than 0.05 level which rejects the null *** regression model was tested for forecasting *** percentage deviation of error for the model is approximately±30%in most of the years.

关键词： yield forecast modelling multiple regression climatic parameters spring wheat

Massive MIMO system lower bound spectral efficiency analysis with precoding and perfect CSI

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Digital Communications and Networks 2021年第3期7卷 342-351页

作者： Tasher Ali Sheikh Joyatri bora.Md Anwar Hussain Department of Electronics and Communication Engineering North Eastern Regional Institute of Science and TechnologyNirjuliArunachal Pradesh791109India

The analytical lower bound of Spectral Efficiency(SE)of downlink transmission of the Massive Multiple Input Multiple Output(Ma-MIMO)system is *** this paper,we derive some novel and approximate mathematical expressions for the lower bound of the SE of a Ma-MIMO with linear precoding schemes,i.e.,Minimum Mean Square Error(MMSE)and Zero-Forcing(ZF).For simulation analysis of the SE,we consider three joint users and antenna scheduling algorithms,namely,the semi-orthogonal,random,and distance-based user scheduling algorithms,whereas the antennas are selected based on Maximum Signal to Noise Ratio(MSNR)with scheduled *** channel between the user and the transmitter is assumed to have characteristics of Small Scale Fading(SSF)and Large Scale Fading(LSF)with the Rayleigh fading *** investigate the effect of the variation of transmitting SNR,the number of base station antennas(M),and the radius(R)of the cell area on the *** simulate the downlink transmission of Ma-MIMO and compare the simulation and analytical *** is observed that the trends of variation of both results are similar to the variation of identical factors,and the difference between the simulated and analytical lower bounds of the SE is approximately 1-1.5 *** analytical lower bound is smaller than the simulation result.

关键词： Fifth-generation Spectral efficiency Ma-MIMO LSF coefficient Precoding

Panic disorder in COVID-19 patients admitted in a tertiary care hospital in South India

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2022年第8期15卷 379-380页

作者： Lakshmi KP Subhash Chandra dipu Thareparambil Sathyapalan Kudrat Jain Department of Psychiatry Amrita Institute of Medical sciences and Research CentreKochiKeralaIndia Department of General Medicine Amrita Institute of Medical sciences and Research CentreKochiKeralaIndia

COVID-19 has led to an increase in psychiatric disorders,stress,trauma and suicidal *** published in the Lancet in 2021 have identified anxiety disorder as the most frequently diagnosed psychiatric disorder in COVID-19 survivors[1].Fear conditioning and hyper-vigilance towards abnormal breathing patterns attributable to COVID-19 or not,can act as etiological and maintenance factors of panic,and hence we should expect an onset or aggravation of panic disorder in COVID-19[2].

关键词： admitted patients hence

Growth inhibitory effect of phenolic extracts of Ziziphus jujuba *** dengue vector Aedes aegypti(L)in parent and F1 generation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2017年第8期10卷 850-854页

作者： Urbbi Devi Dipsikha bora Department of Life Sciences Dibrugarh UniversityDibrugarhAssamIndia

Objective: To evaluate the lethal and emergence inhibitory effect of alkaloid, phenolic and terpenoid extracts of Ziziphus jujuba(Z. jujuba; Rhamnaceae) against Aedes aegypti(Diptera: Culicidae), and to explore the effect of the most effective fraction on developmental and biochemical parameters of the dengue vector. Methods: The fourth instar larvae of Aedes aegypti were exposed to alkaloid, phenolic and terpenoid extracts from Z. jujuba leaves to test their toxicity and emergence inhibitory effects. Phenolic extract, being the most effective was further tested against the mosquitoes for their growth inhibitory effect supported by biochemical changes in the parent and F1 generation. Results: While the different secondary metabolite fractions i.e., alkaloid, phenolics and terpenoid caused mortality at larval and pupal stages, the LC_(50) value was the lowest for phenolic fraction. Further study carried out with the phenolic fraction revealed that it affected growth by decreasing adult life span, fertility and fecundity of the mosquitoes. The reduction in growth was also accompanied by decrease in carbohydrate and lipid levels. Conclusions: It is concluded that the phenolic extract of the leaves of Z. jujuba is a potential candidate for control of Aedes mosquitoes.

关键词： Ziziphus jujuba Toxicity Aedes mosquito

Waste fly ash-ZnO as a novel sunlight-responsive photocatalyst for dye discoloration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Water Science and Engineering 2023年第1期16卷 76-82页

作者： Leena V.bora.Sonal P.Thakkar Kevin S.Vadaliya Nisha V.bora Nirma University AhmedabadGujarat 382481India Government Engineering College ModasaGujarat 383315India

Treating waste with a waste material using freely available solar energy is the most effective way towards sustainable *** this study,a novel photocatalyst,partly derived from waste material from the coal industry,was *** ash hybridized with ZnO(FAeZn)was synthesized as a potential photocatalyst for dye *** synthesized photocatalyst was characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,and ultravioletevisible/near infra-red *** photocatalytic activity was examined with the discoloration of methylene blue used as synthetic dye *** the experiments were performed in direct *** photocatalytic performance of FAeZn was found to be better than that of ZnO and the conventionally popular *** LangmuireHinshelwood model rate constant values of ZnO,TiO2,and FAeZn were found to be 0.016 min1,0.017 min1,and 0.020 min1,*** were two reasons for this:(1)FAeZn was able to utilize both ultraviolet and visible parts of the solar spectrum,and(2)its BrunauereEmmetteTeller surface area and porosity were significantly *** led to increased photon absorption and dye adsorption,thus exhibiting an energy-efficient ***,FAeZn,partly derived from waste,can serve as a suitable material for environmental remediation and practical solar energy applications.

关键词： Photocatalyst ZnO Fly ash Geopolymer Wastewater treatment Methylene blue

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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 Labora.ory 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

Scaling relations of moment magnitude, local magnitude,and duration magnitude for earthquakes originated in northeast India

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

Earthquake Science 2016年第3期29卷 153-164页

作者： Dipok K.bora Department of Physics Diphu Government College

In this study, we aim to improve the scaling between the moment magnitude （Mw）, local magnitude （ME）, and the duration magnitude （MD） for 162 earthquakes in Shillong-Mikir plateau and its adjoining region of northeast India by extending the Mw estimates to lower magnitude earthquakes using spectral analysis of P-waves from vertical component seismograms. The Mw-ML and Mw-MD relationships are determined by linear regression analysis. It is found that, Mw values can be considered consistent with ME and My, within 0.1 and 0.2 magnitude units respectively, in 90 % of the cases. The scaling relationships investigated comply well with similar relationships in other regions in the world and in other seismogenic areas in the northeast India region.

关键词： Local magnitude Moment magnitude Duration magnitude Shillong-Mikir plateau