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Chinese Physics B 2021年第4期30卷 555-564页

作者： Archana V lakshmi Mohan Kathirvel P Saravanakumar S Department of Sciences Amrita School of EngineeringCoimbatoreAmrita Vishwa VidyapeethamIndia Research and Development Center Bharathiar UniversityCoimbatore-641046TamilnaduIndia GRD Center for Materials Research Department of PhysicsP S G College of TechnologyCoimbatore-641004TamilnaduIndia Department of Physics N S S CollegePandalam-689501KeralaIndia

Tin oxide(SnO_(2)) and iron-doped tin oxide(Sn_(1-x)Fe_(x)O_(2),x=0.05 wt%,0.10 wt%) nanoparticles are synthesized by the simple sol-gel *** structural characterization using x-ray diffraction(XRD) confirms tetragonal rutile phases of the *** variations in lattice parameters and relative intensity with Fe-doping concentration validate the incorporation of iron into the *** compressive strain present in the lattice estimated by using peak profile analysis through using Williamson-Hall plot also exhibits the influence of grain boundary formation in the *** radiative recombination and quenching observed in optical characterization by using photoluminescence spectrum(PL) and the shift in the band gap estimated from UV-visible diffused reflectance spectrum corroborate the grain boundary *** spectrum and the morphological analysis by using a field emission scanning electron microscope(FESEM) also indicate the formation of grain *** compositional analysis by using energy dispersive x-ray spectrum(EDAX) confirms Fe in the SnO_(2) *** conductivity studies exhibit that the impendence increases with doping concentration increasing and the loss factor decreases at high frequencies with doping concentration increasing,which makes the Sn_(1-x)Fe_(x)O_(2) a potential candidate for device applications.

关键词： sol-gel compressive strain grain boundary AC conductivity

Multimodality management of resectable gastric cancer: A review

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World Journal of Gastrointestinal Oncology 2014年第10期6卷 393-402页

作者： Helen Shum lakshmi Rajdev Department of Oncology Montefiore Medical Center Albert Einstein College of MedicineBronx NY 10461 United States

Adenocarcinoma of the stomach carries a poor prognosis and is the second most common cause of cancer death worldwide. It is recommended that surgical resection with a D1 or a modified D2 gastrectomy(with at least 15 lymph nodes removed for examination), be performed in the United States, though D2 lymphadenectomies should be performed at experienced centers. A D2 lymphadenectomy is the recommended procedure in Asia. Although surgical resection is considered the definitive treatment, rates of recurrences are high, necessitating the need for neoadjuvant or adjuvant therapy. This review article aims to outline and summarize some of the pivotal trials that have defined optimal treatment options for non-metastatic non-cardia gastric cancer. Some of the most notable trials include the INT-0116 trial, which established a benefit in concurrent chemoradiation and adjuvant chemotherapy. This was again confirmed in the ARTIST trial, especially in patients with nodal involvement. Later, the Medical Research Council Adjuvant Gastric Infusional Chemotherapy trial provided evidence for the use of perioperative chemotherapy. Targeted agents such as ramucirumab and trastuzumab are also being investigated for use in locally advanced gastric cancers after demonstrating a benefit in the metastatic setting. Given the poor response rate of this difficult disease to various treatment modalities, numerous studies are currently ongoing in an attempt to define a more effective therapy, some of which are briefly introduced in this review as well.

关键词： Neoadjuvant chemotherapy Adjuvant che-motherapy Adjuvant chemoradiation Gastric cancer Gastric adenocarcinoma

Performance evaluation of DHRR-RIS based HP design using machine learning algorithms

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Intelligent and Converged Networks 2023年第3期4卷 237-260页

作者： Girish Kumar N G sree Ranga Raju M N the Department of Electronics and Telecommunication Engineering Bangalore Institute of TechnologyVisvesvaraya Technological UniversityBangalore 560004India the Department of Electronics and Communication Engineering Bangalore Institute of TechnologyVisvesvaraya Technological UniversityBangalore 560004India

Reconfigurable Intelligent Surfaces(RIS)have emerged as a promising technology for improving the reliability of massive MIMO communication ***,conventional RIS suffer from poor Spectral Efficiency(SE)and high energy consumption,leading to complex Hybrid Precoding(HP)*** address these issues,we propose a new low-complexity HP model,named Dynamic Hybrid Relay Reflecting RIS based Hybrid Precoding(DHRR-RIS-HP).Our approach combines active and passive elements to cancel out the downsides of both conventional *** first design a DHRR-RIS and optimize the pilot and Channel State Information(CSI)estimation using an adaptive threshold method and Adaptive Back Propagation Neural Network(ABPNN)algorithm,respectively,to reduce the Bit Error Rate(BER)and energy *** optimize the data stream,we cluster them into private and public streams using Enhanced Fuzzy C-Means(EFCM)algorithm,and schedule them based on priority and emergency *** maximize the sum rate and SE,we perform digital precoder optimization at the Base Station(BS)side using Deep Deterministic Policy Gradient(DDPG)algorithm and analog precoder optimization at the DHRR-RIS using Fire Hawk Optimization(FHO)*** implement our proposed work using MATLAB R2020a and compare it with existing works using several validation *** results show that our proposed work outperforms existing works in terms of SE,Weighted Sum Rate(WSR),and BER.

关键词： Reconfigurable Intelligent Surfaces(RIS) Dynamic Hybrid Relay Reflecting(DHRR)-RIS Multi User Multiple Input Multiple Output(MU-MIMO) hybrid precoder machine learning and deep learning algorithms channel state estimation

Characterization of aluminum based functionally graded composites developed via friction stir processing

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Transactions of Nonferrous Metals Society of China 2020年第7期30卷 1743-1755页

作者： Venkatesh BIKKINA Sadasiva Rao TALASILA Kumar adepu Department of Mechanical Engineering National Institute of TechnologyWarangal 506004TelanganaIndia

Al/SiC functionally graded material(FGM) was developed through a novel multi-step friction stir processing(FSP) method. Si C particles with a mean size of 27.5 μm were embedded in the groove on the 6082-Al plate. To create a graded structure over a predefined value, FSP was carried out with three tools with different pin lengths and with varying volume fractions of SiC particles. The structure was formed by passing tools with 1-3 passes with a constant rotational and traveling speeds of 900 r/min and 20 mm/min, respectively. The experiments were conducted at room temperature. Microstructural features of functionally graded(FG) samples were examined by using scanning electron microscopy(SEM) and 3D light microscopy. Mechanical properties in terms of wear resistance and microhardness were thoroughly assessed. The results indicate that the increase in FSP pass number causes more uniform SiC particle dispersion. The microhardness values were impacted by the number of passes and improved by 51.54% for Pass 3 when compared to as-received 6082-Al. Wear resistance of Al/SiC FG samples was found to increase as a result of the addition of SiC particles.

关键词： functionally graded composites friction stir processing silicon carbide AA6082-T6 number of passes

Er^(3+)-Yb^(3+)-Na^(+):ZnWO_(4) phosphors for enhanced visible upconversion and temperature sensing applications

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Journal of Rare Earths 2021年第3期39卷 291-296,I0002页

作者： Sonali Biswas lakshmi Mukhopadhyay Manisha Mondal Vineet Kumar Rai Laser and Spectroscopy Laboratory Department of PhysicsIndian Institute of Technology(Indian School of Mines)Dhanbad-826004JharkhandIndia

The crystal structure and surface morphology of the Er^(3+)/Yb^(3+)/Na+:ZnWO_(4) phosphors synthesized by solid state reaction method were analyzed by X-ray diffraction(XRD) and field emission scanning electron microscopy(FESEM) *** frequency upconversion(UC) emission study in the developed phosphors was investigated by using 980 nm laser diode *** effect of codoping in the Er^(3+):ZnWO_(4) phosphors on the UC emission intensity was *** UC emission bands that are exhibited in the blue(490 nm),green(530,552 nm),red(668 nm) and NIR(800 nm) region correspond to the ^(4)F_(7/2)→^(4)I_(15/2).^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2),^(4)F_(9/2)→^(4)I_(15/2) and ^(4)I9/2→^(4)I_(15/2) transitions,*** temperature sensing performance of the Er^(3+)-Yb^(3+)-Na+:ZnWO_(4) phosphors was investigated based on the 2 H_(11/2)→^(4)I_(15/2) and ^(4)S_(3/2)→^(4)I_(15/2) thermally coupled transitions of the Er^(3+)*** photometric study was also carried out for the developed phosphors.

关键词： Upconversion Non-lanthanides Temperature sensing Fluorescence intensity ratio Rare earths

Green synthesis,characterization and antimicrobial activity of silver nanoparticles using methanolic root extracts of Diospyros sylvatica

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Journal of Environmental Sciences 2017年第5期29卷 157-163页

作者： lakshmi Pethakamsetty Kalyani Kothapenta Hanumanta Rao Nammi lakshmi Kalyani Ruddaraju Pratap Kollu Soon Gil Yoon Sri Venkata Narayana Pammi Department of Microbiology College of Science and Technology Andhra University Visakhapatnam 530003 India DST-PURSE Programme Advanced Analytical Laboratory Andhra University Visakhapatnam 530003 India Sri Vishnu College of Pharmacy Department of Pharmaceutical Technology Vishnupur Bhimavaram A.P. 530041 India DST-INSPIRE Faculty Department of Metallurgical Engineering & Materials Science Indian Institute of Technology Bombay Mumbai 400076 India Department of Materials Science and Engineering Chungnam National University Daeduk Science Town 305-764 Daejeon South Korea

The current research study focuses to formulate the biosynthesized silver nanoparticles for the first time from silver acetate using methanolic root extracts of Diospyros sylvatica,a member of family Ebenaceae. TEM analysis revealed the average diameter of Ag NPs around 8 nm which is in good agreement with the average crystallite size（10 nm）calculated from X-ray Diffraction（XRD）analysis. Further the study has been extended to the antimicrobial activity against test pathogenic Gram（＋）ve,Gram（-）ve bacterial and fungal strains. The bioinspired Ag-NP showed promising activity against all the tested bacterial strains and the activity was enhanced with increased dosage levels

关键词： Root extract Silver nanoparticles Antimicrobial properties

Analysis of Vibrational Properties of Horn-Shaped Magneto-Elastic Single-Walled Carbon Nanotube Mass Sensor Conveying Pulsating Viscous Fluid Using Haar Wavelet Technique

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Acta Mechanica Solida Sinica 2024年第5期37卷 685-699页

作者： M.Mahaveer sree Jayan Lifeng Wang R.Selvamani N.Ramya State Key Laboratory of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China Karunya Institute of Technology and Sciences CoimbatoreTamilnadu641114India Saranathan College of Engineering TiruchirappalliTamilnadu620012India

This research explores the dynamic behaviour of horn-shaped single-walled carbon nanotubes(HS-SWCNTs)conveying viscous nanofluid with pulsating the influence of a longitudinal magnetic *** analysis utilizes Euler-Bernoulli beam model,considering the variable cross section,and incorporating Eringen’s nonlocal theory to formulate the governing partial differential equation of *** instability domain of HS-SWCNTs is estimated using Galerkin’s *** analysis is performed using the Haar wavelet *** critical buckling load obtained in this study is compared with previous research to validate the proposed *** results highlight the effectiveness of the proposed model in assessing the vibrational characteristics of a complex multi-physics system involving *** graphs and tables are presented to visualize the numerical findings pertaining to various system parameters,including the nonlocal parameter,magnetic flux,Knudsen number,and viscous factor.

关键词： Horn-shaped carbon nanotubes Dynamic stability Haar wavelet method Pulsating nanoflow Nonlocal parameter Knudsen number(KN) Viscous fluid

Optimization of rollover stability for a three-wheeler vehicle

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Advances in Manufacturing 2017年第3期5卷 279-288页

作者： S. A. sree Ram P. Raja K. sreedaran School of Mechanical Engineering SASTRA UniversityThanjavur Tamil Nadu 613401 India

An auto rickshaw is a three-wheeled motor vehicle commonly found in Asia, with one front steering wheel and two driven wheels at the back. In automobiles, suspension is used to keep the wheels planted during motion. The trailing arm suspension generally found in Indian automobiles has its roll center on the ground. The vehicle＇s center of gravity is above the ground, which creates a moment during vehicle turning known as the roll moment. When this roll moment exceeds a certain limit, the vehicle becomes unstable. Roll rate can be expressed as degrees per lateral acceleration of the vehicle＇s sprung mass, and is influenced by factors such as wheel rate, motion ratio, and suspension rate. In order to determine an optimized three-wheeler suspension setup, a matrix selection method was used, in which every available suspension type in the market is rated based on selected suspension parameters such as handling, dynamics, and simplicity. From the overall weightage, each suspension type is analyzed and the most appropriate is selected. In order to achieve the objective of improving the overall rollover stability, certain modifications have been applied in the selected suspension design. Generally, if the roll rate of a specific vehicle axle is high, the percentage of weight transfer on the axle will also be high. By improving roll stiffness, the amount of roll can be decreased, and by optimizing the motion ratio, the roll moment can be controlled, thereby increasing the overall rollover stability.

关键词： Roll rate Roll moment Rollover stability ·Trailing arm setup

Dust Deposition’s Effect on Solar Photovoltaic Module Performance:An Experimental Study in India’s Tropical Region

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Journal of Renewable Materials 2022年第8期10卷 2133-2153页

作者： K.R.Chairma lakshmi Geetha Ramadas Department of Electrical and Electronics Engineering R.M.K.Engineering CollegeChennaiIndia

A solar PV panel works with maximum efficiency only when it is operated around its optimum operating point or maximum power ***,the performance of the solar cell is affected by several factors like sun direction,solar irradiance,dust accumulation,module temperature,as well as the load on the *** deposition is one of the most prominent factors that influence the performance of solar *** the solar panel is exposed to the atmosphere,dust will accumulate on its surface,reducing the quantity of sunlight reaching the solar cell and diminishing *** the proposed work,a detailed investigation of the performance of solar PV modules is carried out under the tropical climatic condition of Chennai,India,where the presence of dust particles is very *** data corresponding to four different dust samples of various densities at four solar irradiation levels of 220,525,702,and 905 W/m^(2)are collected,and performance analysis is carried *** on the analysis carried out,the maximum power loss is found to be 73.51%,66.29%,65.46%,and 61.42%,for coal,sand,brick powder,and chalk dust ***,it can be said that coal dust contributes to the maximum power loss among all four dust *** to heat dissipation produced by dust deposition,the performance of solar PV modules is degraded as the temperature rose.

关键词： Solar photovoltaic power generation system dust effect electrical efficiency loss dust samples surface contamination

Ce-substituted Lithium Ferrite:Preparation and Electrical Relaxation Studies

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Journal of Materials Science & Technology 2014年第4期30卷 335-341页

作者： Viswarupa Mohanty Rajesh Cheruku lakshmi Vijayan G.Govindaraj Department of Physics School of PhysicalChemical and Applied SciencesPondicherry University

Ce-substituted lithium ferrite, Li0.5CexFe2.5-x04 （x = 0, 0.05 and 0.1 ） compositions were synthesized from metal nitrates and citric acid by the solution combustion process by keeping the oxidizer to fuel ratio at unity. The thermal decomposition process was investigated by thermogravimetry-differential thermal analysis, which showed a stable phase formation above 600 ℃. The phase composition and molecular bonding of Li0.5CexFe2.5_x04 were characterized by X-ray powder diffraction analysis and Fourier transform infrared spectroscopy, respectively. An extensive study of electrical relaxation process has been represented with impedance and modulus as a function of frequency at different temperatures. The activation energy obtained from both the formalisms was found to be equal within the error. The dc conductivity and hopping frequency were thermally activated and their activation energies were found to be in the range of 0.69-0.64 eV for x = 0.05. The scaling of modulus and impedance were used to understand the electrical relaxation behaviour of the compositions and they suggest the time temperature superposition principle.

关键词： Lithium ferrite Solution combustion synthesis Inverse spinel Electrical relaxation process and scaling