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Photonic crystal ber-based multi-wavelength Brillouin ber laser with dual-pass ampli cation con guration

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Chinese Optics Letters 2011年第2期9卷 48-50页

作者： R.Parvizi S.W.Harun n.M.Ali n.S.Shahabuddin H.Ahmad Photonics Laboratory Department of Physics University of Malaya Department of Electrical Engineering Faculty of Engineering University of Malaya

A simple technique for achieving a stable, room temperature and multi-wavelength lasing with narrow linewidth is demonstrated using Brillouin ber laser （BfL） with a 100-m-long photonic crystal ber （PCf） in conjunction with a dual-pass configuration. A broadband ber Bragg grating （fBG） operating in the C-band region is incorporated at the end side of the setup to allow a dual-pass operation. The proposed BfL can operate at any wavelength depending on the Brillouin pump wavelength and the fBG＇s reflection region used. With a Brillouin pump （BP） of 15.7 dBm, approximately 7 Stokes and 4 anti-Stokes lines are obtained with a line spacing of 0.08 nm.

关键词： PCf fBG

Morphology and magnetic traits of strontium nanohexaferrites:Effects of manganese/yttrium co-substitution

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Journal of Rare Earths 2019年第7期37卷 732-740页

作者： M.A.Almessiere y.Slimani H.S.El Sayed A.Baykal Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of nano-Medicine Research Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of Biophysics Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia

Doped strontium(Sr) hexaferrites appeared potential candidates for microwave absorber *** by this idea, we examined the influence of manganese(Mn) and yttrium(y) co-substitution on the microstructures,morphology and magnetic properties of Sr nanohexaferrites(Sr1-xMnxfe12-yyyO19,where 0.0 ≤ x = y ≤ 0.5) synthesized via citrate sol-gel auto-combustion technique. As-prepared samples were thoroughly characterized using diverse analytical tools. X-ray diffraction pattern reveals a single Mhexagonal crystalline phase. fE-SEM, TEM, HR-TEM show a hexagonal platelet-like structure. The magnetic hysteresis loops(measured at room and low temperature) of the as-prepared nanohexaferrites exhibit ferromagnetic(fM) behavior. Magnetic parameters including the saturation magnetization,remanence, coercive and magneto-crystalline anisotropy field are found to decrease with the increase in Mn2+ and y3+ contents. Zero-and normal-field cooled magnetization measurements in the range of 2-400 K display the complete absence of blocking temperature, confirming the characteristic ferromagnetic behavior of the proposed composition.

关键词： Strontium hexaferrite Sol-gel auto-combustion Microstructure Morphology Magnetic properties Rare earths

Better together? Treating traumatic brain injury with minocycline plus n-acetylcysteine

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neural Regeneration Research 2022年第12期17卷 2589-2592页

作者： Siobhán Lawless Peter J.Bergold Graduate Program in neural and Behavioral Sciences State University of New York-Downstate Health Sciences UniversityBrooklynNYUSA Department of Physiology and Pharmacology State University of New York-Downstate Health Sciences UniversityBrooklynNYUSA

Traumatic brain injury has a complex pathophysiology that produces both rapid and delayed brain damage. Rapid damage initiates immediately after injury. Treatment of traumatic brain injury is typically delayed many hours, thus only delayed damage can be targeted with drugs. Delayed traumatic brain injury includes neuroinflammation, oxidative damage, apoptosis, and glutamate toxicity. Both the speed and complexity of traumatic brain injury pathophysiology present large obstacles to drug development. Repurposing of food and Drug Administration-approved drugs may be a highly efficient approach to get therapeutics to the clinic. This review examines the preclinical outcomes of minocycline and n-acetylcysteine as individual drugs and compares them to the minocycline plus n-acetylcysteine combination. Both minocycline and n-acetylcysteine are food and Drug Administration-approved drugs with pleiotropic therapeutic effects. As individual drugs, minocycline and n-acetylcysteine are well tolerated, with known pharmacokinetics, and enter the brain through an intact blood-brain barrier. At concentrations greater than needed for antimicrobial action, minocycline is a potent anti-inflammatory minocycline, also acts as an antioxidant and inhibits multiple enzymes that promote brain injury including metalloproteases, caspases, and polyADP-ribose-polymerase-1. n-acetylcysteine alone is also an antioxidant. It increases brain glutathione, prevents lipid oxidation, and protects mitochondria. n-acetylcysteine also acts as an anti-inflammatory as well as increases extracellular glutamate by activating the X;cystine-glutamate antitransporter. These multiple actions of minocycline and n-acetylcysteine have made them attractive candidates to treat traumatic brain injury. When first dosed within the one hour after injury, either minocycline or n-acetylcysteine improves a diverse set of therapeutic outcome measures in multiple traumatic brain injury animal models. A small number of clinical

关键词： clinical trial outcome measures preclinical testing rodent models of traumatic brain injury therapeutic time window

Control of Lymphocyte Trafficking through b2-adrenergic Receptors

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Control of Lymphocyte Trafficking through b2-adrenergic Rece...

Microstructure and Microhardness of Laser Beam Welded Al-Mg-Mn-Zr-Er Joint

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作者： A.nakai y.Hayano f.furuta K.Suzuki WPI Immunology frontier Research Center Osaka University

Lymphocyte trafficking among lymphoid organs is important for immunosurveillance and pathogenesis of inflammatory diseases,where chemotactic factors,represented by chemokines,and their receptors play essential ***,it ... 详细信息

关键词： lymphocyte trafficking adrenergic nerves adrenergic receptor chemokine receptor

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稀有金属材料与工程 2011年第S4期40卷 111-114页

作者： yang Dongxia,Li X y,He D y,nie Zouren,Huang Hui School of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China Beijing Univ Technol Sch Mat Sci & Engn Beijing 100124 Peoples R China

In this work,the weldability of the alloy Al-Mg-Mn-Zr-Er with high power nd:yAG laser has been *** were subjected to three different welding heat inputs to obtain various weld *** main objective of the present work has been to investigate the change of microstructure and microhardness at the Al-Mg-Mn-Zr-Er laser weld *** showed that the top width of the bead was larger at the higher laser *** structure refinement was found in welded metal,especially at higher laser *** was also verified that the microhardness of weld bead was raised with the decrease of laser power,due to the microstructure refinement at the condition of lower laser power.

关键词： microstructure microhardness aluminum alloy laser welding

Synthesis of CaWO_4:Eu^(3+) phosphor powders via ethylene glycol route and its optical properties

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Journal of Rare Earths 2012年第4期30卷 310-314页

作者： K.Gayatri Sharma n.Rajmuhon Singh Department of Chemistry Manipur University Canchipur-795003 Imphal Manipur India

Eu3＋ doped CaWO4 with tetragonal system were prepared at comparatively low temperature （125 ℃） in ethylene glycol medium. The phosphor was further investigated by X-ray difffactometer （XRD）, photoluminescence spectrophotometer （PL）, fourier transform infra red （fT-IR） spectroscopy and transmission electron microscopy （TEM）. XRD analysis indicated a decrease in the unit cell volume of CaWO4 with increasing Eu3＋ ion concentration. It indicated the homogeneous substitution of Ca2＋ ions in CaWO4 by the Eu3＋ ions. TEM images showed that the particle size ranged from 20 to 200 nm and it could extend the application of the nanoparticles. The photoluminescence study showed that the intensity of electric dipole transition （SD0→Tf2） at 614 nm dominated over the magnetic dipole transition （SD0→Tfx） at 592 nm. The optimum concentration of Eu3＋ for the highest luminescence was found to be 20 at.%. The as prepared samples were found to be dispersible in water and methanol.

关键词： CaWO4:Eu3+ capping agent photoluminescence dispersible rare earths

RESEARCH On LASER DIRECT DEPOSITIOn PROCESS Of Ti-6Al-4V ALLOy

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 171-180页

作者： S.y. Gao y.Z. Zhang L.K. Shi B.L. Du M.Z. Xi H.Z. Ji Mechanical Engineering College Yanshan University O~mhuangdao 066004 China Beijing General Research Institute for nonferrous Metals Beijing 100088 China

Laser direct deposition （LDD） of metallic components is an advanced technology of combining CAD/CAM （computer aided design/computer aided manufacturing）, high power laser, and rapid prototyping. This technology uses laser beam to melt the powders fed coaxiaUy into the molten pool by the laser beam to fabricate fuUy dense metallic components. The present article mainly studies the LDD of Ti-6Al-4V alloy, which can be used to fabricate aircraft components. The mechanical properties of the Ti-6Al-4V alloy, fabricated by LDD, are obtained using the tension test, and the oxygen content of used powders and deposited specimens are measured. In the present article, it can be seen that the mechanical properties obtained using this method are higher than the ones obtained by casting, and equal to those got by wrought anneal. One aircraft part has been made using the LDD process. Because of this aircraft part, with sophisticated shape, the effect of the laser scanning track on the internal soundness of the deposited part was discussed.

关键词： laser direct deposition Ti-6Al-4V alloy mechanical property depositing process aircraft component

STRUCTURAL fIRE EnGInEERInG STUDy On UnPROTECTED LOnG SPAn STEEL TRUSSES

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STRUCTURAL FIRE ENGINEERING STUDY ON UNPROTECTED LONG SPAN S...

A nEW SESQUITERPEnE fROM LIGULARIA nELUMBIfOLIA

影响中国——第二届中国钢结构产业高峰论坛

作者： H.C.HO K.f.CHUnG y.WOnG Department of Civil and Structural Engineering The Hong Kong Polytechnic UniversityHong Kong SAR. Arup fire Ove Arup & Partners Hong Kong LimitedHong Kong SAR.

This paper presents a structural fire engineering study on the thermal and structural performance of a 33.6 x 33.6 m space truss comprising of 8 longitudinal and 4 transverse unprotected steel *** of the finite element modeling are thoroughly described,and both non-linear thermal and structural analyses are presented to illustrate the general modelling procedures. Moreover,a number of general principles on data analyses and interpretation of the numerical results are discussed whilst specific failure criteria for the long span trusses in terms of various stress and deformation levels in members and in supports are also *** is envisaged that the experiences gained from the present study will contribute to the wide application of structural fire engineering study in steel building structures.

关键词： Structural fire engineering unprotected steel fire scenario finite element modelling.

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Chinese Chemical Letters 1995年第7期6卷 583-584页

作者： Peng, HR Jia, ZJ yang, L Zhao, y Lanzhou Univ Inst Organ Chem State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China

A new guaiane sesquiterpene was isolated from Ligularia nelumbifolia. Its structure was elucidated by spectroscopic methods including 2D-nMR techniques and showed to be 4 alpha ,9 alpha ,10 beta -tri-acetoxy-1 beta, 5...

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