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Geoscience Frontiers 2016年第5期7卷 793-798页

作者： r.P.Tripathi Beena Bhatia r.sharma k.r.Patel s.s.Meena Girish Ganwani s.c.Mathur Department of Physics Jai Narain Vyas University Jodhpur 342 005 India Department of Geology Jai Narain Vyas University Jodhpur 342 005 India

^57Fe Mossbauer spectroscopic study was carried out on the organic rich sedimentary samples collected at different depth intervals from newly drilled test well chinnewala Tibba-1（cT-1） located in Jaisalmer Petroliferous basin India. It is found that iron is mainly distributed in high spin Fe^3＋and Fe^2＋ state in clay minerals. The plot of Fe^2＋/（Fe^2＋＋ Fe^3＋） indicates the presence of poor redox conditions in the *** obtained are also compared with those already reported in the literature. This comparison shows that there may exist a correlation between prospecting of the basin, the redox environment in sediments and the nature of iron bearing minerals distributed in the sedimentary sequence.

关键词： Jaisalmer petroliferous basin chinnewala Tibba structure ^57Fe Mossbauer spectroscopic study source rocks Hydrocarbon prospecting

calcium phosphate conversion technique:A versatile route to develop corrosion resistant hydroxyapatite coating over Mg/Mg alloys based implants

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Journal of Magnesium and Alloys 2022年第7期10卷 1821-1845页

作者： G.s.Hikku c.Arthi r.B.Jeen robert k.Jeyasubramanian r.Murugesan Medical Bionanotechnology Faculty of Allied Health SciencesChettinad Hospital and Research InstituteChettinad Academy of Research and EducationKelambakkamTamilnadu 603103India Nanobiotechnology Amirta Centre for Nanoscience and Molecular MedicineAmirtha Vishwa VidhyapeethamErnakulamKerala 682041India Department of Mechanical Engineering AAA College of Engineering and TechnologySivakasiTamilnadu 626005India Department of chemistry Mepco Schlenk Engineering CollegeSivakasiTamilnadu 626005India karpaga Vinayaga Institute of Medical sciences and research centre PalayanoorTamilnadu 603308India

Globally,vast research interest is emerging towards the development of biodegradable orthopedic implants as it overcomes the toxicity exerted by non-degradable implants when fixed in the human body for a longer *** this context,magnesium(Mg)plays a major role in the production of biodegradable implants owing to their characteristic degradation nature under the influence of body ***,Mg is one of the essential nutrients required to perform various metabolic activities by the human cells,and therefore,the degraded Mg products will be readily absorbed by the nearby ***,the higher corrosion rate in the biological environment is the primary downside of using Mg implants that liberate H2gas resulting in the formation of ***,in certain cases,Mg undergoes complete degradation before the healing of damaged bone tissue and cannot serve the purpose of providing mechanical ***,many studies have been focused on the development of different strategies to improve the corrosion-resistant behavior of Mg according to the *** this regard,the present review focused on the limitations of using pure Mg and Mg alloys for the fabrication of medical implants and how the calcium phosphate conversion coating alters the corrosive tendency through the formation of hydroxyapatite protective films for enhanced performance in medical implant applications.

关键词： Biodegradable implants Magnesium controlled corrosion Alloying Hydroxyapatite calcium phosphate conversion coating

structural and optoelectronic properties of sprayed sb:snO_2 thin films:Effects of substrate temperature and nozzle-to-substrate distance

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Journal of semiconductors 2011年第10期32卷 1-9页

作者： A.r.Babar s.s.shinde A.V.Moholkar c.H.Bhosale k.Y.rajpure Electrochemical Materials Laboratory Department of PhysicsShivaji University

The influence of substrate temperature and nozzle-to-substrate distance（NsD） on the structural,morphological, optical and electrical properties of sb：snO_2 thin films prepared by chemical spray pyrolysis has been *** structural,morphological,optical and electrical properties were characterized by using XrD,sEM, UV-visible spectrophotometry and Hall effect measurement *** was seen that the films are polycrystalline, having a tetragonal crystal structure with strong orientation along the（200） *** pyramidal crystallites formed due to coalescence were observed from sEM *** values of highest conductivity,optical transmittance and figure of merit of about 1449（Ω·cm）^（-1）,70%and 5.2×10^（-3）□/Ω,respectively,were observed for a typical film deposited using optimal conditions（substrate temperature = 500℃and NsD = 30 cm）.

关键词： substrate temperature NsD structural optoelectronic properties

The influence of spark plasma sintering temperatures on the microstructure,hardness,and elastic modulus of the nanocrystalline Al-xV alloys produced by high-energy ball milling

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Journal of Materials science & Technology 2022年第27期122卷 68-76页

作者： J.christudasjustus c.s.Witharamage Ganesh Walunj T.Borkar r.k.Gupta Department of Materials science and Engineering North Carolina State UniversityRaleighNC 27606United States Department of Mechanical Engineering Cleveland State UniversityClevelandOH 44115United States

Al-xV alloys(x=2 at.%,5 at.%,10 at.%)with nanocrystalline structure and high solid solubility of V were produced in powder form by high-energy ball milling(HEBM).The alloy powders were consolidated by spark plasma sintering(sPs)employing a wide range of temperatures ranging from 200 to 400°*** microstructure and solid solubility of V in Al were investigated using X-ray diffraction analysis,scanning electron microscope and transmission electron *** microstructure was influenced by the sPs temperature and V content of the *** alloys exhibited high solid solubility of V–six orders of magnitude higher than that in equilibrium state and grain sizesPs *** formation of Al3V intermetallic was detected at 400℃.Formation of a V-lean phase and bimodal grain size was observed during sPs,which increased with the increase in sPs *** hardness and elastic modulus,measured using nanoindentation,were significantly higher than commercial *** example,Al-V alloy produced by sPs at 200℃ exhibited a hardness of 5.21 GPa along with elastic modulus of 96.21 *** evolution of the microstructure and hardness with sPs temperatures has been discussed.

关键词： spark plasma sintering Aluminum alloys Nanocrystalline alloys High-energy ball milling Nanoindentation Hardness Elastic modulus

synthesis of ceO_2 nanoparticles using flame-assisted spray pyrolysis and solid state diffusion routes

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rare Metals 2015年第1期34卷 6-11页

作者： k.r.Nemade s.A.Waghuley Department of Physics Sant Gadge Baba Amravati University

The stable and crystalline phase of pure nano- structured ceO2 was directly synthesized by flame-assisted spray pyrolysis and solid state diffusion route. Different characterization techniques, including X-ray diffraction （XrD）, scanning electron microscopy （sEM）, Fourier trans- form infrared spectroscopy （FTIr）, ultraviolet-visible （UV- Vis）, and thermo gravimetric analysis （TGA） were employed to examine the structural, morphological, optical, and thermal properties of the final product. similarly, the comparative carbon dioxide （cO2）-sensing response of as-synthesized ceO2 nanoparticles by both routes was also reported. The ceO2 nanoparticles synthesized by solid state diffusion method exhibit good sensitivity （3.38 %） at room temperature, low operating temperature （398 k）, fast response time （32 s）, and recovery time （36 s） along with good stability.

关键词： cO2 gas sensing Flame-assisted spraypyrolysis solid state diffusion

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural regeneration research 2025年第8期20卷 2307-2308页

作者： Larissa M.G.cassiano roney s.coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIkV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(cNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural regeneration research 2025年第5期20卷 1336-1349页

作者： chao Weng Adam M.r.Groh Moein Yaqubi Qiao-Ling cui Jo Anne stratton G.r.Wayne Moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by robertson and río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus rNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

One-step fabrication of ultrathin layered 1T@2H phase Mos2 with high catalytic activity based counter electrode for photovoltaic devices

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Journal of Materials science & Technology 2020年第16期47卷 94-101页

作者： k.silambarasan J.Archana s.Harish M.Navaneethan r.sankar Ganesh s.Ponnusamy c.Muthamizhchelvan k.Hara Functional Materials and Energy Devices Laboratory Department of Physics and NanotechnologySRM Institute of Science and TechnologyKattankulathur603203India Nanotechnology research center(Nrc) Faculty of Engineering and TechnologySRM Institute of Science and TechnologyKattankulathur603203India research Institute of Electronics Shizuoka University3-5-1 JohokuNaka-KuHamamatsuShizuoka432-8011Japan Graduate school of science and Technology Shizuoka University3-5-1 JohokuNaka-KuHamamatsuShizuoka432-8011Japan

The metallic phase of molybdenum disulfide(M-Mos2)and semiconductor phase of molybdenum disulfide(s-Mos2)was synthesized by hydrothermal method,using cetyltrimethylammonium bromide(cTAB)as a *** structural and elemental composition confirmed the formation of M-Mos2 and *** the morphological analysis layered nanosheets with an inter-layered distance of 0.62 nm for M-Mos2 and 0.95 nm for s-Mos2 was ***-transform infrared(FT-Ir)spectral analysis was used to investigate the existence of cTAB functional *** peak at 885 cm-1 attributed to the cH3 bond which confirmed the presence of cTAB in the *** anodic and cathodic peak separation(Epp)values of the counter electrode(cE)has showed at 468.28 mV(M-Mos2)and 540.87 mV(s-Mos2).The M-Mos2 thin film shows higher catalytic activity when compared to s-Mos2 due to more active sites and electronic *** power conversion efficiency of M-Mos2 cE based device exhibits higher efficiency compared to s-Mos2 cE based device.

关键词： M-Mos2 s-Mos2 Layered nanosheet catalytic Power conversion

Plasmonic enhancement of upconversion emission in Ag@NaYF4:Er^3+/Yb^3+phosphor

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Journal of rare Earths 2018年第9期36卷 903-910页

作者： s.k.Maurya s.r Tiwari A.kumar k.kumar Optical Materials and Bio-imaging research Laboratory Department of Applied PhysicsIndian Institute of Technology(Indian School of Mines)Dhanhad-826004India

In this article upconversion luminescence of silver nanoparticles（AgNPs） coated NaYF4：Er3＋/Yb3＋phosphor nano-particles was *** prepared samples were characterized through various *** surface plasmon band is observed for prepared AgNPs by analyzing UV-vis measurements and is used to enhance the upconversion *** the upconversion measurement the emission bands are observed at 522,546,and 656 nm corresponding to the 2 H11/2→ 4115/2,4 s3/2→4 I15/2and 4 F9/2→4 I15/2 levels,*** upconversion emission intensity of the above bands is found to enhance for sample containing 1 mmol *** time of 4 s3/2 and 4F9/2 levels is found to decrease on coating of AgNPs and hence intensity enhancement is assumed due to the surface plasmon resonance（sPr） effect.

关键词： Upconversion phosphor surface plasmon resonance Decay time analysis cIE diagram rare earths

spectroscopic investigations and luminescence spectra of sm3+ doped soda lime silicate glasses

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Journal of rare Earths 2009年第5期27卷 773-780页

作者： Y.k. sharma s.s.L. surana r.k. singh Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India Department of Physics J. N. V. University Jodhpur-342001 India Department of Physics Govt. Post Graduate College Rudrapur 263153 (U S Nagar) India

sm3+ doped soda lime silicate glasses co-doped with As2O3 were prepared and characterised by measuring their absorption spectra in UV-VIs/NIr regions and luminescence spectra in the visible region. Judd-Ofelt intensity parameters, Ωλ, were evaluated from the measured intensities of the various absorption bands. Ωλ parameters of these glasses were compared with the Ωλ parameters of other reported sm3+ glasses to study the bonding environment surrounding the sm3+ in the present glasses. Presence of [AsO4]3– tetrahedra in the second coordination sphere around the central sm3+ ion made these glasses less covalent as compared to other oxide glasses but the ratio Ω4/Ω6 of the 1.83 indicated them to be fairly stable. With the help of Ωλ parameters and luminescence data for various emission lines, radiative properties for different emission lines were calculated. The values of radiative properties indicated that 4G5/2→6H7/2 and 4G5/2→6H9/2 transitions responsible for orange luminescence might be used in the development of materials for LED's and other optical devices in the visible region.

关键词： rare earth glasses Judd-Ofelt theory absorption spectroscopy luminescence