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Journal of Rare Earths 2016年第1期34卷 21-29页

作者：廖侹乔刘宏 R. hUSSIN Z. IBRAhIM K. DERAMAN h.o. lintang W.N.W ShAMSURI Phosphor Research Group Department of Physics Faculty of Seience Universiti Teknologi Malaysia Skudai 81310 Johor Malaysia State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China Catalytic Science and Tech.o.ogy Research Group Ibnu Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Skudai 81310 Johor Malaysia

A series of Eu3＋ and Dy3＋ doped/co-doped as well as un-doped BaB2Si2os phosphors were synthesized via solid state reaction method. The PL result showed typical blue and green emission from Dy3＋ and red emission from Eu3＋. The f-f transitions in- volving the lanthanide ions along with dopant site occupancy were discussed thoroughly. Phonon assisted energy transfer process was observed from Eu3＋ to Dy3＋, which enhanced the emissions of Dy3＋. Combinations of the emissions from Eu3＋ and Dy3＋ showed a possible white to red tuneable emission on the CIE diagram. The white warmth emissions of the phosphor were revealed to be ad- justable th.o.gh designing the dopant concentration and excitation wavelengths. An unusual energy transfer that originated from Eu3＋ to Dy3＋ was also discovered and the energy transfer mechanism was discussed. Proposed energy transfer mechanism was investigated using luminescence decay lifetime. All the phosphor exhibited efficient excitation in the UV range which matched well with the emissions from GaN-based LED chips. This presented the BaB2Si208 phosphor as a promising candidate for white LED applications. The effects of doping on the structural properties and the optical band gap of BaB2Si208 phosphor were also discussed in this study.

关键词： BaB2Si2o8:Eu3+/Dy3+ phosphor energy transfer rare earths

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hoSSEINI o.BALILAShAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined th.o.etically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the h.o. and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition th.o.em for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered th.o.ghout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： Stress concentration

Structural and luminescence studies of europium ions in lithium aluminium borophosphate glasses

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Journal of Rare Earths 2014年第7期32卷 585-592页

作者： Poh Sum Wong Ming hua Wan Rosli hussin hendrik o.lintang Salasiah Endud Phosphor Research Group Department of Physics Faculty of Science Universiti Teknologi Malaysia Ibnu Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Department of Chemistry Faculty of ScienceUniversiti Teknologi Malaysia

Eu3＋ doped borophosphate glasses with the chemical composition 20Li2o-30Al2o3-10B2o3-40P2o5-xEu2o3（where x=0.05 mol.%, 0.1 mol.%, 1.0 mol.%, 1.5 mol.% and 2.0 mol.%） were prepared by conventional melt quenching technique. The structural and luminescence properties of the prepared Eu3＋ doped borophosphate glasses were studied and compared with reported results. The XRD pattern showed the amorphous nature of the prepared glasses. Whereas, the FTIR spectra revealed the vibrational modes in the prepared glasses. The bonding parameters（ β and ？） were calculated th.o.gh the excitation spectra. Judd-ofelt（J-o） intensity parameters were calculated from the emission spectra and were used to determine transition probability（A）, stimulated emission cross-section（σE P）, radiative lifetime（τR） and branching ratios（βexp） for the transition 5D0→7Fj（j=1, 2, 3 and 4） of Eu3＋ ions. Furthermore, the luminescence intensity ratio（R） of 5D0→7F2 to 5D0→7F1 transition was also calculated. Transition 5D0→7F2 had the highest value of stimulated emission cross-section and branching ratios and the results were comparable with the reported values. This indicated that the present glass is promising host material for Eu3＋ doped fiber amplifiers.

关键词： europium ions luminescence properties borophosphate glasses Judd^ofelt analysis decay time rare earths

Innate and adaptive T cells in influenza disease

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Frontiers of Medicine 2018年第1期12卷 34-47页

作者： Simone Nfissing Sneha Sant Marios Koutsakos Kanta Subbarao Thi h.o. Nguyen Katherine Kedzierska Department of Microbiology and Immunology University of Melbourne at the Peter Doherty Institute for Infection and Immunity Parkville 3010 Victoria Australia World health.o.ganisation (Who) Collaborating Centre for Reference and Research.o. Influenza at the Peter Doherty Institute for Infection and Immunity Melbourne 3000 Victoria Australia

Influenza is a major global health problem, causing infections of the respiratory tract, often leading to acute pneumonia, life-threatening complications and even deaths. over the last seven decades, vaccination strategies have been utilized to protect people from complications of influenza, especially groups at high risk of severe disease. While current vaccination regimens elicit strain-specific antibody responses, they fail to generate cross-protection against seasonal, pandemic and avian viruses. Moreover, vaccines designed to generate influenza- specific T-cell responses are yet to be optimized. During natural infection, viral replication is initially controlled by innate immunity before adaptive immune responses （T cells and antibody-producing B cells） achieve viral clearance and host recovery. Adaptive T and B cells maintain immunological memory and provide protection against subsequent infections with related influenza viruses. Recent studies also shed light on the role of innate T- cells （MAIT cells, y~ T cells, and NKT cells） in controlling influenza and linking innate and adaptive immune mechanisms, thus making them attractive targets for vaccination strategies. We summarize the current knowledge on influenza-specific innate MAIT and γδ T cells as well as adaptive CD8＋ and CD4＋ T cells, and discuss how these responses can be harnessed by novel vaccine strategies to elicit cross-protective immunity against different influenza strains and subtypes.

关键词： influenza innate T cells CD4+ and CD8+ T cells vaccination

Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “on Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Comparative chemical sensor for detection of ch.o.ium(Ⅵ) in aqueous solution

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optoelectronics Letters 2025年第1期21卷 21-27页

作者： Sura h.AL-REKABI A.A.ALWAhIB Electrical Technique Department Al Suwayrah Technical Institute Middle Technical University Laser and optoelectronics Department University of Technology-Iraq

A process for purifying aqueous solutions containing heavy and toxic metals such as ch.o.ium（Cr） has been investigated. one of the extremely harmful pollutants in rivers and seawater is the heavy metal ions due to their direct impacts on human, animals and plants are hexavalent Cr（Ⅵ）. Consequently, highly sensitive sensor to detect Cr is essential. Surface plasmon resonance（SPR） technique has attracted huge research interest in detecting heavy metals specifically. In this study, three types of prism-based SPR sensor, gold（Au）/silver（Ag）, Au/polyaniline（PANI） and Au/titanium dioxide（Tio2） nanostructured films, are investigated as potential sensing material to detect the presence of Cr（Ⅵ） ions in water. The base Au layer with thickness of 48.3 nm is deposited on a glass slide for all sensors. For Au/Ag, Au/PANI nanofibers and Au/Tio2sensor films, the Cr（Ⅵ） concentration is varied from 1 ppm to 15 ppm with sensitivity of 0.270 °ppm-1, 0.082 °ppm-1and 0.039 °ppm-1, respectively. Based on these results, the Au/PANI nanofibers are the most sensitive to Cr（Ⅵ） among the tested sensing materials.

关键词： Titanium dioxide

Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri h.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

Comparison of Impact Properties for Carbon and Low Alloy Steels

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Journal of Materials Science & Tech.o.ogy 2011年第10期27卷 931-936页

作者： o.h.Ibrahim Metallurgy Dept. Nuclear Research CentreAtomic Energy Authority

The impact properties of hot rolled carbon steel （used for the manufacture of reinforcement steel bars） and the quenched ＆ tempered （Q＆T） low alloy steel （used in the pressure vessel industry） were determined. The microstructure of the hot rolled carbon steel contained ferrite/pearlite phases, while that of the quenched and tempered low alloy steel contained bainite structure. Impact properties were determined for both steels by instrumented impact testing at temperatures between -150 and 200℃. The impact properties comprised total impact energy, ductile to brittle transition temperature, crack initiation and propagation energy, brittleness transition temperature and cleavage fracture stress. The Q＆T low alloy steel displayed much higher resistance to ductile fracture at high test temperatures, while its resistance to brittle fracture at low test temperatures was a little higher than that of the hot rolled carbon steel. The results were discussed in relation to the difference in the chemical composition and microstructure for the two steels.

关键词： Ferritic/pearlitic steel Bainitic steel Impact properties

芳族自由基阴离子裂解反应的半经典轨迹法研究

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化学学报 1987年第4期45卷 334-339页

作者： Villar,h.o. oastro,E.A. Rossi,R.A. INIFTA Division Quimica Teorica C. C. 16 Sucursal 4 1900 La plata INIFTA Division Quimica Teorica C. C. 16 Sucursal 4 1900 La plata INIFTA Division Quimica Teorica C. C. 16 Sucursal 4 1900 La plata Departamento de Quimica organica Facultad de Ciencias Quimicas C. C. 61 Sucursal 16 5016 Cordoba ARGENTINA Departamento de Quimica organica Facultad de Ciencias Quimicas C. C. 61 Sucursal 16 5016 Cordoba ARGENTINA Departamento de Quimica organica Facultad de Ciencias Quimicas C. C. 61 Sucursal 16 5016 Cordoba ARGENTINA

研究了芳族自由基负离子裂解反应中沿着反应坐标两个势能超曲面可能存在交叉点的问题。结果表明,沿着该反应坐标可能发生内转换。利用Landau-Zerner模型,研究了通过非绝热带的跃迁几率,并定性地将之与分解速率常数作了比较。

关键词：反应坐标芳族裂解反应