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Wireless Engineering and Technology 2013年第1期4卷 59-63页

作者： G. A. Bidkar R. m. vani P. V. Hungund Department of PG Studies and Research in Applied Electronics Gulbarga University Gulbarga University Science Instrumentation Centre Gulbarga University Gulbarga

Compact microstrip antennas have recently received much attention due to the increasing demand of small antennas for personal communication equipment. The problem of achieving a wide impedance bandwidth for compact microstrip antennas is becoming an important topic in microstrip antenna design. In this paper the design and development of a 2 × 1 array of a low cost slotted microstrip line fed shorted patch antenna (mFSPA) has been presented. Both the shorted patch and microstrip line feed network have air substrate. The material cost is thus reduced to a minimum. The array consists of two adjacent patches fed, using a simple microstrip T network. The impedance bandwidth of nearly 40%, covering the bandwidth requirement of 1750 mHz band is obtained. Also the antenna exhibits dual band operation. The cross polarization radiation in H-Plane observed with a single element antenna has been reduced considerably with 2 × 1 array. A peak antenna gain of 9.2 dBi is obtained with a small variation of 0.8 dBi. From the results obtained it is clear that the antenna array studied has a low cost fabrication and is suitable for applications in DCS mobile communication base station.

关键词： microstrip Antenna Compact Antenna Shorted Patch microstrip Line Fed

Total Electron Content and Anomalous Appearance of GPS Satellites as Pointers to Epicentre Identification of major Japan Earthquake of 2011

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Positioning 2012年第1期3卷 7-12页

作者： minakshi devi Ananda Kumar Barbara Department of Physics Gauhati University Guwahati India

The paper presents an analysis of variations in Total Electron Content (TEC) observed through Global Positioning System (GPS) at Guwahati (26?10'N, 91?45'E), in relation to the Japan Earthquakes (EQs) of march 9 and 11, 2011. For this purpose, the azimuthal positions and trajectories of abnormally increased number of satellites at the epicentre location appearing into the Field Of View (FOV) of GPS antenna at Guwahati and consequent pseudo enhancement in TEC are taken as inputs. The paper discusses how the analysis results could provide warning alarms of two earthquakes possibly one on march 8 or 9 and the other on march 11 or 12, 2011 with epicenter positions around 135?E to 145?E and 35?N to 40?N, that coincides with location of Japan Earthquakes. A projected forecast on EQ magnitude of m > 8.5 is also made. The explanations to the observed modifications in TEC features and abnormal increase in number of satellites are purported to be the result of coupling between lithosphere and troposphere forced in by pre-earthquake processes that had spread the zone of activities to as far as Guwahati.

关键词： GPS-TEC Earthquake Satellite Track Radio Refractive Index

Computation of Energy, Intensity and Thermodynamic Parameters for the Interaction of Ln(III) with Nucleic Acid: Analysis of Structural Conformations, Chemical Kinetics and Thermodynamic Behaviour through 4f-4f Transition Spectra as Probe

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Journal of materials Science and Chemical Engineering 2018年第7期6卷 169-183页

作者： N. Bendangsenla T. moainla Juliana Sanchu m. Indira devi Department of Chemistry Patkai Christian College Chumoukedima Nagaland India Department of Chemistry Nagaland University Lumami Zunheboto Nagaland India

Nucleosides and Nucleotides are polydentate ligands, offering potential binding sites for metal ions. Energy interaction parameters: Slater Condon Fk (cm-1), Spin Orbit interaction ξ4f? (cm-1), Nephelauxetic Ratio (β), Bonding (b1/2) and Covalency (δ) parameter for the interaction of Pr(III) with Nucleoside and Nucleotide are evaluated to study the mode of binding of the Nucleic Acid Components (Guanosine and Guanosine Triphosphate) with Pr(III). Further Intensity Parameters like Oscillation Strength and Judd Ofelt Parameter (T2, T4, T6) have been evaluated to investigate degree of inner or outer sphere co-ordination of Pr(III) with Nucliec Acid ligands. Comperative Absorption Spectra in different solvents substantiate the informations, gathered from the evaluated values of both energy interaction and intensity parameters. Further evaluation of Thermodynamic parameters (ΔG, ΔH and ΔS) through Kinetic studies enable to provide the detailed information about the reaction pathways and thermodynamic behavour of the complexation process of neucleosides and nucleotides with Pr(III) and Ca2+.

关键词： Nucleic Acid 4f-4f Transition Spectra Nephelauxetic Effect Judd-Ofelt Parameters Slator Condon Reaction Rate Thermodynamic

Kinetics study of metaxalone degradation under hydrolytic, oxidative and thermal stress conditions using stability-indicating HPLC method

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Journal of Pharmaceutical Analysis 2012年第6期2卷 431-436页

作者： Vamsi Krishna marothu Rajendra N. Dash Saritha Vemula Shravani Donkena Ramesh devi madhavi Gorrepati Alliance Institute of Advanced Pharmaceutical and Health Sciences

An isocratic stability indicating RP-HPLC-UV method is presented for the determina- tion of metaxalone （mET） in the presence of its degradation products. The method uses Dr. maisch C18 column （250 mm × 4.6 mm, 5μm） with mobile phase consisting of acetonitrile-potassium dihydrogen orthophosphate buffer with 4 mL of 0.4% triethyl amine （pH 3.0; 10 mm）（58：42, v/v） at a flow rate of 1.0 mL/min, pH of the buffer was adjusted with o-phosphoric acid. UV detection was performed at 225 nm. The method was validated for specificity, linearity, precision, accuracy, limit of detection, limit of quantification and robustness. The calibration plot was linear over the concentration range of 1-100 μg/mL having a correlation coefficient （r2） of 0.999. Limits of detection and quantification were 0.3 and 1μg/mL, respectively. Intra-day and inter-day precision （% RSD） was 0.65 and 0.79 respectively. The proposed method was used to investigate the degradation kinetics of mET under different stress conditions employed. Degradation of mET followed a pseudo-first-order kinetics, and rate constant （K）, time left for 50% potency （t1/2）, and time left for 90% potency 090） were calculated.

关键词： metaxalone Degradation kinetics RP-HPLC-UV

Analytical Expression for the Concentration of Substrate and Product in Immobilized Enzyme System in Biofuel/Biosensor

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Applied mathematics 2015年第7期6卷 1148-1160页

作者： R. malini devi O. m. Kirthiga L. Rajendran Department of mathematics The Standard Fireworks Rajaratnam College for Women Sivakasi India Department of mathematics The Madura College Madurai India

In this paper, an approximate analytical method to solve the non-linear differential equations in an immobilized enzyme film is presented. Analytical expressions for concentrations of substrate and product have been derived for all values of dimensionless parameter. Dimensionless numbers that can be used to study the effects of enzyme loading, enzymatic gel thickness, and oxidation/ reduction kinetics at the electrode in biosensor/biofuel cell performance were identified. Using the dimensionless numbers identified in this paper, and the plots representing the effects of these dimensionless numbers on concentrations and current in biosensor/biofuel cell are discussed. Analytical results are compared with simulation results and satisfactory agreement is noted.

关键词： michaelis-menten Kinetics Biofuel and Biosensor Homotopy Perturbation method Immobilized Enzyme Systems

通过上流式厌氧污泥床（UASB）系统处理甘蔗废水制氢

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通过上流式厌氧污泥床（UASB）系统处理甘蔗废水制氢

作者： devi muhtariana 东北林业大学

学位级别：硕士

上流式厌氧污泥床(UASB)是一种生物反应器装置,可以利用有机原料和富含碳水化合物的基质产生沼气。UASB反应器已广泛应用于各种底物的制氢。众所周知,它的能源需求低,能够产生富含甲烷的沼气作为可回收能源,污泥产量低。它也成功地应用... 详细信息

上流式厌氧污泥床(UASB)是一种生物反应器装置,可以利用有机原料和富含碳水化合物的基质产生沼气。UASB反应器已广泛应用于各种底物的制氢。众所周知,它的能源需求低,能够产生富含甲烷的沼气作为可回收能源,污泥产量低。它也成功地应用于处理各种类型的废水。UASB被称为最健壮的高速厌氧反应器,目前已广泛安装了近1000个反应器。UASB是一种操作稳定、过程高效的反应堆。甘蔗废水已被用作制氢的底物。研究的主要参数包括产氢量、pH值、水力停留时间(HRT)、COD和底物浓度。底物浓度设计分别为1.33gr/L、1.78gr/L、2.22gr/L、4gr/L和8gr/L。HRT设计为下降模式,分别为24小时、12小时、7小时和4小时。在79天的运行时间内,总产气量可达到8 m3。氢产率随底物浓度的增加而增加。但是,本研究的产氢量低于其他研究。运行期间COD去除率最低为0.78%,最高为90.25%。对UASB处理单糖、复糖和多糖进行了比较研究。氢、二氧化碳和甲烷是主要由UASB反应器产生的气体类型,可以是单级的,也可以是两级的。乙酸、丁酸、丙酸、异戊酸和戊酸是可溶性代谢产物,主要由单糖(单糖)、复糖(双糖)和多糖废水产生。UASB反应器是一种很有发展前途的沼气特别是氢气的反应器。然而,要优化UASB的性能,特别是在提高产氢量方面,还需要更多的研究。这将使UASB反应器成为制氢的首选系统。

关键词： UASB反应器氢气产量甘蔗废水水力停留时间底物浓度

Association between Homa Index and Vascular Endothelial Dysfunction in Type 2 Diabetic Patients

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Open Journal of Internal medicine 2014年第4期4卷 123-129页

作者： N. Rama Kumari I. Bhaskara Raju m. Aruna devi m. Pallam Praveen Department of Cardiology Nizam’s Institute of Medical Sciences Hyderabad India Gandhi medical College Secunderabad India Department of Radiology Nizam’s Institute of Medical Sciences Hyderabad India

Introduction: In recent years, flow mediated dilatation (FmD) has become a popular technique in cardiovascular medicine. HOmA-IR was accepted to determine the insulin sensitivity as a valuable standard. In this study, we evaluated the association between HOmA-IR (homeostasis model assessment of insulin resistance) and vascular endothelial dysfunction, as assessed by endothelium- dependent flow-mediated dilatation (FmD) and nitroglycerin-mediated dilatation (NmD), in type 2 Diabetic (Dm) patients. material and methods: Eighty four (84) consecutive out-patients were enrolled. HOmA-IR was calculated as fasting insulin (μU/ml) multiplied by fasting plasma glucose (FPG) (mg/dl) and divided by 405. The ultrasound method for measuring FmD and NmD has been used. Out of 84 patients, 42 patients were in control group and 42 patients were in diabetic group, which were further subdivided into two groups based on HOmA-IR > 3.0 and above was considered as Group I and HOmA IR ma Glucose (mmol/dl) (7.74 ± 2.56, 6.81 ± 1.9, p mean FmD in controls and cases (Group I and Group II) was 15.36 ± 9.56, 4.15 ± 2.29, 12.21 ± 6.24 (p mD percentage change (mI (p ma Insulin (p mD, NmD and HOmA-IR. Discussion: We conclude that increased HOmA-IR in hyperglycaemic patients is associated with severe endothelial dysfunction which is the marker of the atherosclerosis. Thus the measurement of endothelial vasomotor function which is a comprehensive analysis of atherosclerotic burden may provide a better predictive value of future cardiovascular events than the analysis of each of the traditional risk factors alone.

关键词： Flow mediated Dilatation (FmD) Homeostasis model Assessment of Insulin Resistance (HOmA-IR) Nitroglycerin-mediated Dilatation (NmD)

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气候变化对毛里求斯海岸带的影响

华东师范大学学报（自然科学版） 2020年第S1期 104-108页

作者： PERIANEN Yuvna devi 肖溪浙江大学海洋学院浙江舟山316021 自然资源部第二海洋研究所海洋生态系统与生物地球化学实验室杭州310012 毛里求斯环境部固体废物管理和气候变化处毛里求斯

气候变化是人类面临的主要全球性挑战之一.发展中国家受到气候变化的强烈影响,例如毛里求斯这样的小岛屿国家.本研究目的是分析毛里求斯降水、温度、海平面上升、海滩侵蚀和自然灾害活动的长期变化规律,评估其沿海地区的气候变化脆弱性... 详细信息

气候变化是人类面临的主要全球性挑战之一.发展中国家受到气候变化的强烈影响,例如毛里求斯这样的小岛屿国家.本研究目的是分析毛里求斯降水、温度、海平面上升、海滩侵蚀和自然灾害活动的长期变化规律,评估其沿海地区的气候变化脆弱性,并提出减缓气候变化影响的对策.原始数据源自毛里求斯气象局、环境部和中央统计局.从1904年到2015年,毛里求斯年降水量呈稳定下降趋势.回归分析显示,在1950—2007年间,全国平均温度每十年增加0.18℃.在过去十年中,已经观察到海平面上升正在以年均5.6 mm的速度加速. 1975年以来,可发现强烈气旋(强风超过345 km/hr)的数量呈上升趋势.海滩侵蚀的加剧使某些沿海地区的海滩宽度缩水了多达20 m.为了缓解海平面上升、珊瑚礁下降、温度升高以及这些问题对海岸侵蚀、泻湖质量和游客来访造成的影响,政府可与其他相关实体组织合作,实施适当的政策,以减少沿海地区应对气候变化的脆弱性.具体措施包括预防措施(如增加海岸线与陆上建筑的距离)、非结构性措施(如海岸和海滩管理)和结构性干预措施等(如使用坚硬的海岸线保护结构、防波堤).目前毛里求斯已开发出一个综合性海岸带管理框架,并通过环境影响评估机制来限制海岸开发活动.

关键词：气候变化海岸带毛里求斯海平面上升海滩侵蚀

morphological and Rheological Properties of Starches Separated from Cultivars of Rice (<i>Oryza sativa</i>L.) from North East India

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American Journal of Plant Sciences 2015年第12期6卷 2019-2031页

作者： Nikhil K. Chrungoo Ayam Gangarani devi Depatment of Botany North Eastern Hill University Shillong India

Starch granules isolated from different accessions of rice from North East India showed a typical polygonal morphology with size ranging from 3.4 ± 0.8 μm to 6.4 ± 1.2 μm. The apparent amylose content (AAC) of the granules varied from 1.9% to 28.33%. Our results identify starch from IC-583088 as “waxy” and IC-583085, IC-583038, DPRR-168 as “very low” amylo-. The coefficient of resistance to flow (n) for starch pastes from the varieties of rice studied in the present investigation recorded a value of deviates from the Newtonian flow indicating the pseudoplastic nature of starches isolated from these varieties. While starch pastes from the accession IC-583088 recorded the highest ‘‘n’’ value of 0.6, that from the accession IC-545197 showed the lowest value of 0.03. The variations in coefficient of resistance to flow clearly revealed a higher ‘‘n’’ value for starch pastes from the “waxy” and ‘‘low” amylo-cultivars than the “intermediate” or ‘‘high” amylo-cultivars. Our results clearly established characteristic rheological properties for starches from the accessions SKY-AK-1608, IC-583035, YS-RC-219, IC-564939 and IC-332963, which exhibited greater resistance to thinning and shearing than other varieties.

关键词： Rice Starch Apparent Amylose Content Rheology

Influence of climate and litter quality on litter decomposition and nutrient release in sub-tropical forest of Northeast India

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Journal of Forestry Research 2010年第2期21卷 143-150,I0004页

作者： N.Bijayalaxmi devi P.S.Yadava Department of Life Sciences manipur University

Leaf litterfall,litter decomposition and nutrient return through litterfall of three dominant species,*** serrata,Schima wallichi and Lithocarpus dealbata were studied in different months throughout the year to assess the input and release of nutrient in the forest soil of a sub-tropical mixed oak forest of manipur,northeastern *** in northeastern region of India are economically important species for the production of Tasar *** monthly litterfall ranged from 25.6 g·m^-2（July） to 198.0 g·m^-2（February） and annual litterfall was 1093.8g·m^-2 in the forest *** initial month（on November 3）,the concentrations of N and C were the highest in ***,followed by *** and lowest in ***,whereas lignin and cellulose concentrations at initial month were the highest in ***,followed by *** and ***（k=0.54） exhibited a high rate of litter decomposition,coinciding with high concentrations of N and C and low cellulose in the litter at initial ***,low rate of litter decomposition in ***（k=0.33） coincided with low value of N and C and highest value of lignin and cellulose at initial *** remaining biomass in different months was positively correlated with the lignin,C,C/N ratio and cellulose,but it negatively correlated with nitrogen concentrations at initial *** rate of litter decomposition was the highest in rainy summer months,owing to congenial environmental conditions and lowest rate of litter decomposition in cool and dry winter months.

关键词： nutrient use efficiency Quercus serrata nitrogen lignin and litter quality