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Journal of Materials science & Technology 2013年第10期29卷 898-902页

作者： c.s.naveen M.L.Dinesha H.s.Jayanna Department of PG studies and Research in Physics Kuvempu University

ZnO nanoparticles of different sizes were prepared by varying the molar ratio of glycine and zinc nitrate hexahydrate as fuel and oxidizer （0.1, 0.8, 1.11, 1.3, 1.5, 1.7, 2.0） by simple solution combustion method. UV-Visible spectrophotometry studies show that, the band gap of the prepared ZnO nanoparticles increases with increasing fuel to oxidant （F/O） molar ratio up to 1.7 revealing the formation of ZnO nanoparticles. The decrease in band gap for the sample of F/O molar ratio 2.0 is due to an increase in particle size. Powder X-ray diffraction patterns of the prepared samples show the formation of single phase ZnO nanoparticles and the particle size decreases with increasing F/O molar ratio up to 1.7. surface morphology of the prepared samples was studied by scanning electron microscopy and it was observed that, the porosity increases with increasing F/O molar ratio. Dc electrical conductivity at room temperature and in the temperature range of 303-563 K was studied for all the samples and the results revealed that, the sample of F/O molar ratio 1.7 has low electrical conductivity at room temperature and high EAR （high temperature activation energy） compared to other samples.

关键词： ZnO nanoparticles structural characterization Electrical conductivity

Low-Frequency Dependence of conductivity and Dielectric Properties of Polyaniline/ZnFe_(2)O_(4) Nanocomposites

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chinese Physics Letters 2011年第11期28卷 218-221页

作者： G.D.Prasanna H.s.Jayanna Ashok R Lamani M.L.Dinesha c.s.naveen G.J.shankaramurthy Department of PG studies and Research in Physics Kuvempu UniversityShankarghatta-577451KarnatakaIndia Bapuji Institute of Engineering and Technology Davangere-577004KarnatakaIndia

conducting polyaniline/ZnFe_(2)O_(4) nanocomposites are synthesized by using a simple and inexpensive one-step in-situ polymerization method in the presence of ZnFe2O4 nanoparticles.The structural,morphological and electrical properties of the samples are characterized by x-ray diffraction,Fourier transform infrared spectra and scanning electron microscopy.These results reveal the formation of polyaniline/ZnFe2O4 nanocomposites.The morphology of these samples is studied by scanning electron microscopy.Further,the ac conductivity(σac)of these composites is investigated in the frequency range of 1 kHz–10 MHz.The presence of polarons and bipolarons are responsible for the frequency dependence of ac conductivity in these nanocomposites.The ac conductivity is found to be constant up to 1MHz and thereafter it increases steeply.The ac conductivity of 0.695 s・cm^(−1) at room temperature is observed as the maxima for the polyaniline with 40wt%of the ZnFe2O4 nanocomposite.

关键词： composites ZnFe2O4 conductivity

Optical and structural properties of highly porous shell structured Fe doped TiO_2 thin films

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Rare Metals 2014年第5期33卷 578-582页

作者： c.s.naveen P.Raghu H.M.Mahesh K.Narasimha Rao R.Rakesh Kumar A.R.Phani Department of Electronic science Bangalore UniversityJnanabharathi Department of Instrumentation and Applied Physics Indian Institute of Science Nano-Research for Advanced Materials and Technologies (Nano-RAM Technologies)

TiO2thin films with 0.2 wt%, 0.4 wt%, 0.6wt%, and 0.8 wt% Fe were prepared on glass and silicon substrates using sol–gel spin coating technique. The optical cut-off points are increasingly red-shifted and the absorption edge is shifted over the higher wavelength region with Fe content increasing. As Fe content increases, the optical band gap decreases from 3.03 to 2.48 eV whereas the tail width increases from 0.26 to 1.43 eV. The X-ray diffraction（XRD） patterns for doped films at 0.2 wt% and0.8 wt% Fe reveal no characteristic peaks, indicating that the film is amorphous whereas undoped TiO2exhibits（101） orientation with anatase phase. Thin films of higher Fe content exhibit a homogeneous, uniform, and nanostructured highly porous shell morphology.

关键词： Fe TiO2 Porous shell sol–gel

cool white light and tunable multicolor emission from Tb^(3+)/Dy^(3+)co-activated glasses under different excitations for WLEDs

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Journal of Rare Earths 2024年第1期42卷 46-56,I0002页

作者： L.Vijayalakshmi K.naveen Kumar Jong Dae Baek Department of Automotive Engineering Yeungnam UniversityGyeongsanGyeongbuk38541Republic of Korea Department of Mechanical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

A set of co-doped(Tb^(3+)/Dy^(3+))lithium zinc borate(LZB)glasses were developed by melt quenching.The structural evaluation was performed for synthesized glassy matrices.The Dy^(3+)and Tb^(3+)individually doped glasses exhibit intense yellow and green luminescence bands at 575 nm(^(4)F_(9/2)→^(6)H_(13/2))and543 nm(^(5)D_(4)→^(7)F_(5)),respectively.The sensitization effect of Dy^(3+)on Tb^(3+)was analyzed by increasing the Tb^(3+)content with respect to the optimum Dy^(3+)content(0.5 mol%)in Dy^(3+)/Tb^(3+).The spectral overlay of Dy^(3+)luminescence and Tb^(3+)absorption profiles,Dy^(3+)/Tb^(3+)PL spectra under different excitations 352,362,376,and 385 nm,shortening decay lifetimes of Dy^(3+)in Dy^(3+)/Tb^(3+)co-activated glasses,energy transfer(ET)parameters,chromaticity coordinates and their corresponding correlated temperatures all help to explain ET from Dy^(3+)to Tb^(3+).At 385 nm of Dy^(3+)excitation,the optimized co-activated(0.5Dy^(3+)+1.0Tb^(3+)):LZB glass displays cool white light emission.The non-radiative ET from Dy^(3+)to Tb^(3+)is dominated by electric dipole-dipole interaction and its ET efficiency was calculated to be 63%.At the same time,reverse ET from Tb^(3+)to Dy^(3+)was also analyzed.The shift in color coordinates from dominant yellow to greenish-yellow,green and white light emission suggests that Dy^(3+)/Tb^(3+)coactivated LZB glasses can be a potential candidate for UV converted multicolor and white light emitting devices.

关键词： Rare earths Photoluminescence Energy transfer spectral overlap Decay lifetime Multicolor emitting LEDs

Efficacy of stromal vascular fraction for knee osteoarthritis:A prospective,single-centre,non-randomized study with 2 years follow-up

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World Journal of Orthopedics 2024年第5期15卷 457-468页

作者： Madhan Jeyaraman naveen Jeyaraman Tarun Jayakumar swaminathan Ramasubramanian Rajni Ranjan saurabh Kumar Jha Ashim Gupta Department of Orthopaedics ACS Medical College and HospitalDr MGR Educational and Research InstituteChennaiTamil Nadu 600077India Department of Biotechnology School of Engineering and TechnologySharda UniversityGreater NoidaUttar Pradesh 201310India Department of Orthopaedics and Regenerative Medicine South Texas Orthopaedic Research InstituteLaredoTX 78045United States Department of Orthopaedics KIMS-Sunshine HospitalHyderabadTelangana 500032India Department of Orthopaedics Government Medical CollegeOmandurar Government EstateChennaiTamil Nadu 600002India Department of Orthopaedics School of Medical Sciences and ResearchSharda UniversityGreater NoidaUttar Pradesh 201306India Department of Zoology Kalindi CollegeUniversity of DelhiNew Delhi 110008India Department of Orthopaedics and Regenerative Medicine Regenerative OrthopaedicsNoida 201301Uttar PradeshIndia Department of Orthopaedics and Regenerative Medicine Future BiologicsLawrencevilleGA 30043United States Department of Orthopaedics and Regenerative Medicine BioIntegrateLawrencevilleGA 30043United States

BAcKGROUND current osteoarthritis(OA)treatments focus on symptom relief without addressing the underlying disease process.In regenerative medicine,current treatments have limitations.In regenerative medicine,more research is needed for intra-articular stromal vascular fraction(sVF)injections in OA,including dosage optimization,long-term efficacy,safety,comparisons with other treatments,and mechanism exploration.AIM To compare the efficacy of intra-articular sVF with corticosteroid(Ics)injections in patients with primary knee OA.METHODs The study included 50 patients with Kellgren-Lawrence grades II and III OA.Patients were randomly assigned(1:1)to receive either a single intra-articular sVF injection(group A)or a single intra-articular Ics(triamcinolone)(group B)injection.Patients were followed up at 1,3,6,12,and 24 months.Visual analog score(VAs)and International Knee Documentation committee(IKDc)scores were administered before the procedure and at all followups.The safety of sVF in terms of adverse and severe adverse events was recorded.statistical analysis was performed with sPss Version 26.0,IBM corp,chicago,IL,United states.REsULTs Both groups had similar demographics and baseline clinical characteristics.Follow-up showed minor patient loss,resulting in 23 and 24 in groups A and B respectively.Group A experienced a notable reduction in pain,with VAs scores decreasing from 7.7 to 2.4 over 24 months,compared to a minor reduction from 7.8 to 6.2 in Group B.This difference in pain reduction in group A was statistically significant from the third month onwards.Additionally,Group A showed significant improvements in knee functionality,with IKDc scores rising from 33.4 to 83.10,whereas Group B saw a modest increase from 36.7 to 45.16.The improvement in Group A was statistically significant from 6 months and maintained through 24 months.cONcLUsION Our study demonstrated that intra-articular administration of sVF can lead to reduced pain and improved knee function in patients with primary knee OA.More adequately powe

关键词： Knee osteoarthritis Adipose tissue stromal vascular fraction Regenerative medicine Orthobiologics

Advancing orthopaedic trauma care through WhatsApp:An analysis of clinical and non-clinical applications,challenges,and future directions

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World Journal of Orthopedics 2024年第6期15卷 529-538页

作者： Ravi saini Madhan Jeyaraman naveen Jeyaraman Vijay Kumar Jain swaminathan Ramasubramanian Karthikeyan P Iyengar Department of Orthopaedics Atal Bihari Vajpayee Institute of Medical SciencesDr Ram Manohar Lohia HospitalNew Delhi 110001India Department of Orthopaedics ACS Medical College and HospitalDr MGR Educational and Research InstituteChennai 600077Tamil NaduIndia Department of Orthopaedics Government Medical CollegeOmandurar Government EstateChennai 600002Tamil NaduIndia Department of Trauma and Orthopaedics Southport and Ormskirk HospitalsMersey and West Lancashire Teaching NHS TrustSouthport PR86PNUnited Kingdom

The integration of WhatsApp,a widely-used instant messaging application(IMA),into the realm of orthopaedics and trauma surgery has emerged as a significant development in recent years.This paper explores the multifaceted role of WhatsApp in orthopaedics,focusing on its clinical and non-clinical applications,advantages,disadvantages,and future prospects.The study synthesizes findings from various research papers,emphasizing the growing reliance on mobile technology in healthcare.WhatsApp’s role in orthopaedics is notable for its ease of use,real-time communication,and accessibility.clinically,it facilitates triage,teleconsultation,diagnosis,treatment,patient advice,and post-operative monitoring.Non-clinically,it supports telemedicine,teleradiology,virtual frac-ture clinics,research,and education in orthopaedic surgery.The application has proven beneficial in enhancing communication among healthcare teams,providing quick responses,and motivating junior physicians.Its use in educational settings has been shown to improve learner’s understanding and patient care.However,the use of WhatsApp in orthopaedics is not without challenges.Risks include the potential spread of misleading information,privacy concerns,and issues with image quality affecting diagnosis and treatment decisions.The paper acknowledges the importance of maintaining professional boundaries and the need for oversight measures to ensure content accuracy.Looking forward,the potential of WhatsApp and similar IMAs in orthopaedics lies in their ability to streamline data collection and retrieval,improve doctor-patient communication,and address challenges like bureaucratic red tape and limited resources.The paper suggests that future orthopaedic practice,particularly in emergency departments,will increasingly rely on such technologies for efficient patient management.This shift,however,must be approached with an understanding of the ethical,legal,and practical implications of integrating social media and mobile technology in healthcare.

关键词： social media WhatsApp Orthopaedics Trauma Research

Outcome of patients with traumatic cranial nerve palsy admitted to a university hospital in Nepal

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中华神经外科杂志(英文) 2024年第2期10卷 1-7页

作者： Kumari Khusbu Gautam naveen Parajuli Monika singh shreejana Pradhananga Amit sedai Gopal shilpakar sushil sharma Mohan Raj Maharajgunj Medical campus Institute of Medicine Tribhuvan University Maharajgunj Kathmandu Nepal Department of Research Institute of Medicine Maharajgunj Kathmandu Nepal Department of Neurosurgery Tribhuvan University Teaching Hospital Maharajgunj Kathmandu Nepal

Background cranial nerve palsy (cNP) is a common complication of traumatic brain injury (TBI). Despite a high incidence of TBI in Nepal (382 per 100,000), literature on the specific management and outcome of cNP is lacking. This study aimed to examine the outcomes of TBI patients involving single versus multiple cNP.Methods A retrospective chart review of 170 consecutive TBI patients admitted to the tertiary neurosurgical center in Nepal between April 2020 and April 2022 was conducted. Demographic, clinical, and etiological characteristics; imaging findings; and management strategies were recorded, compared, and analyzed using descriptive statistics. The Glasgow Outcome scale Extended (GOsE) was used to measure the outcomes in two groups of patients (single and multiple cNP) at 3 months.Results Out of 250 eligible patients, 80 were excluded and cNP was noted in 29 (17.1%) of the remaining 170. The median age was 34.9 years, and falls (60.6%) were the most common cause of trauma. TBI severity was categorized based on Gcs: mild (82.4%), moderate (15.9%), and severe (1.8%). cranial nerve involvement was seen in 29 (17.05%) patients: single cranial nerve involvement in 26 (89.65%) and multiple nerve involvement in 3 (10.34%). The most common isolated cranial nerve involved was the oculomotor nerve (37.9%). cT findings revealed a maximum of skull fractures with no significant association between cNP and cT findings.conclusions cNP is a common consequence of TBI with the most common etiology being falls followed by RTA. single cNP was more common than multiple cNP with no significant difference in the outcome in the 3-month GOsE score. Further research is needed to determine the burden of traumatic cNP and establish specific management guidelines for different types of cNP.

关键词： cranial nerve palsy Nepal Outcome Traumatic brain injury

Early Phases of star Formation: Testing chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： N.c.Martinez s.Paron cONIcET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

star-forming processes strongly influence the IsM chemistry.Nowadays,many high-quality databases are available at millimeter wavelengths.Using them,it is possible to carry out studies that review and deepen previous results.If these studies involve large samples of sources,it is preferred to use direct tools to study the molecular gas.With the aim of testing these tools such as the use of the HcN/HNc ratio as a thermometer,and the use of H^(13)cO^(+),Hc_(3)N,N_(2)H^(+) and c_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(HMPOs),hot molecular cores(HMcs) and ultracompact H II regions.We found that the use of the HcN/HNc ratio as a universal thermometer in the IsM should be taken with care because the HcN optical depth is a big issue that can affect the method.Hence,this tool should be utilized only after a careful analysis of the HcN spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption features.We point out that the analysis of the emission of H^(13)cO^(+),Hc_(3)N,N_(2)H^(+) and c_(2)H could be useful to trace and distinguish regions among IRDcs,HMPOs and HMcs.The molecular line widths of these four species increase from the IRDc to the HMc stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular clumps.Our results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation IsM:molecules IsM:clouds

Geochemistry and depositional environment of fuchsite quartzites from sargur Group,western Dharwar craton,India

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Acta Geochimica 2024年第3期43卷 555-570页

作者： c.s.sindhuja G.Harshitha c.Manikyamba K.s.V.subramanyam csIR(council of scientific and Industrial Research)-National Geophysical Research Institute(NGRI) Uppal RoadHyderabad 500007India

Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar craton including the oldest(~3.3 Ga)sargur Group of western Dharwar craton.The present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the Ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation history.Their major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and rutile.The geochemical com-positions are characterized by high siO_(2),Al_(2)O_(3),low MgO,caO,strongly enriched cr(1326–6899 ppm),Ba(1165–3653 ppm),sr(46–210 ppm),V(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(Ucc).The Ucc normalized rare earth element(REE)patterns are characterized by depleted light REE[(La/sm)Ucc=0.33–0.95]compared to heavy REE[(Gd/Yb)_(Ucc)=0.42–1.65]with conspicuous positive Eu-anomalies(Eu/Eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered barites.The overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin environ-ment.The comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by cr-richfluids released during high-grade metamorphism of associated ultramafic rocks.The sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of cr-richfluids and the formation of fuchsite quartzite during or after the orogeny.Thesefindings sug-gest a pre-existing stable crust prior to the sargur Group and the link between orogenic events and various mineral deposits in the Dharwar craton.

关键词： Dharwar craton Ghattihosahalli Fuchsite quartzite Provenance Depositional setting

Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： N.IQBAL J.cHOI s.F.sHAH c.LEE s.LEE Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline Ni-rich LiNixMnyco_(z)O_(2)(x≥0.8)(NMc)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of primary NMc particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more homogeneously.Besides,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress mitigation.This paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of NMc active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation Ni-rich LiNixMnyco_(z)O_(2)(x>0.8)(NMc)