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Tm^(3+) interactions in LiYF_4 studied by high-resolution spectroscopy

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Journal of Rare Earths 2009年第4期27卷 633-636页

作者： s.A.Klimin d.s.Pytalev Institute of spectroscopy Russian Academy of Sciences 5 Fizicheskaya Str. 142190 Troitsk Moscow region 142190 Russia

We used the high-resolution spectroscopy to study the interactions that Tm3＋ ion in a LiYF4 crystal is subjected to. several crystal field transitions with low integral intensity were found not registered before by means of ordinary spectroscopy. spectral evidences for interionic, hyperfine, isotopic interactions, and for a resonant broadening of the ground state are presented.

关键词： high-resolution Fourier-transform speclroscopy hyperfme structure isotopic structure pair centers rare earths

seismic fragility assessment of RC frame structure designed according to modern Chinese code for seismic design of buildings

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 331-342页

作者： d. Wu s. Tesfamariam s.F. stiemer d. Qin Key Laboratory of Earthquake Engineering and Applied Technique of Guangdong Province Guangzhou 501405 China school of Engineering University of British Columbia Kelowna V1 V 1 V7 Canada dept. of Civil Engineering University of British Columbia Vancouver V6T 1Z4 Canada dept. of Civil Engineering Radio Film and Television Design and Research Institute Beijing 100045 China

Following several damaging earthquakes in China, research has been devoted to find the causes of the collapse of reinforced concrete （RC） building sand studying the vulnerability of existing buildings. The Chinese Code for seismic design of Buildings （CCsdB） has evolved over time, however, there is still reported earthquake induced damage of newly designed RC buildings. Thus, to investigate modern Chinese seismic design code, three low-, mid- and high-rise RC frames were designed according to the 2010 CCsdB and the corresponding vulnerability curves were derived by computing a probabilistic seismic demand model （PsdM）.The PsdM was computed by carrying out nonlinear time history analysis using thirty ground motions obtained from the Pacific Earthquake Engineering Research Center. Finally, the PsdM was used to generate fragility curves for immediate occupancy, significant damage, and collapse prevention damage levels. Results of the vulnerability assessment indicate that the seismic demands on the three different frames designed according to the 2010 CCsdB meet the seismic requirements and are almost in the same safety level.

关键词： building damage criteria collapse ratio probabilistic seismic demand model (PsdM) fragility curves Chinese Code for seismic design of Buildings (CCsdB)

Quadratic stabilization of a nonlinear aeroelastic system using a novel Neural-Network-based controller

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science China(Technological sciences) 2011年第5期54卷 1126-1133页

作者： d. sFFKER Chair of dynamics and Control University of Duisburg-Essen

This contribution proposes a novel neural-network-based control approach to stabilize a nonlinear aeroelastic wing section. With the prerequisite that all the states of the system are available, the proposed controller requires no comprehensive information about structural nonlinearity of the wing section. Furthermore, the proposed control approach requires no human intervention of designing goal dynamics and formulating control input function, which is difficult to be realized by the typical neural-network-based control following an inverse control scheme. simulation results show that the proposed controller can stabilize the aeroelastic system with different nonlinearities.

关键词： quadratic stabilization neural-network nonlinear aeroelastic control cognition

Management of difficult inflammatory bowel disease:where are we now?

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World Journal of Gastroenterology 2000年第3期6卷 315-323页

作者： d.s. Rampton Reader & Consultant Gastroenterologist Gastrointestinal Science Research Unit and Digestive Diseases Research CentreSt Bartholomews & Royal London School of Medicine and DentistryLondon E1 2ADUK

INTROdUCTION Medical care of patients with inflammatory bowel disease(IBd) comprise general measures and specific pharmacological,nutritional,endoscopic and surgical

关键词： inflammatory bowel diseases/therapy colitis/therapy Crohn disease/therapy endoscopy gastrointestinal social support azathioprine

Electrical and optical properties of lithium borate glasses doped with Nd_2O_3

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Journal of Rare Earths 2012年第8期30卷 785-789页

作者： R.s. Gedam d.d. Ramteke department of Applied Physics Visvesvaraya National Institute of Technology

Glass series with general formula 25Li2O-（75-x）B2O3-xNd2O3 was prepared by conventional melt quench technique. Electrical and optical characterizations of these glasses were carried out. It was observed that conductivity of glasses decreased and activation energy in- creased with the addition of Nd2O3. The density and refractive index of the glasses increased while optical band gap and radiation length de- creased due to structural changes.

关键词： conductivity density refractive index optical absorption Tauc's plot rare earths

Luminescence properties of Gd^(3+) containing glasses for ultra-violet(UV) light

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Journal of Rare Earths 2014年第5期32卷 389-393页

作者： d.d.Ramteke R.s.Gedam department of Applied Physics Visvesvaraya National Institute of Technology

Effect of Gd2O3 addition on optical properties of 27.5 Li2O-72.5 B2O3 glass systems was studied. density, differential thermal analysis （dTA）, optical absorption spectra and luminescence technique were used to characterize the prepared glasses. Emis- sion spectra showed two band 6p7/2→8s7/2 （311.5 nm） and 6p5/2→8s7/2 （305 nm） under the excitation of 274 nm. The intense emission at 311.5 nm suggested that these glasses could be useful as source of narrowband UV light.

关键词： glasses rare earths absorption band gap luminescence UV light

dynamic responses of two buildings connected by viscoelastic dampers under bidirectional earthquake excitations

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 137-150页

作者： Z.d. Yang Eddie s.s. Lam department of Civil and Environmental Engineering The Hong Kong Polytechnic University

In this study,dynamic responses of two buildings connected by viscoelastic dampers under bidirectional excitations are extensively *** two buildings are a 10-story building and a 16-story building,with the shorter building on the *** dampers are installed at all fl oors of the shorter *** of motion are formulated using a fractional derivative model to represent the viscoelastic *** cases are considered with mass eccentricities at 0,10% and-10% with respect to the dimensions of the *** responses of the buildings are numerically predicted at different damper *** simulation results indicated that the maximum horizontal responses of the buildings without eccentricities are signifi cantly ***,torsional effects are adversely *** asymmetric buildings,the effectiveness of the connecting dampers is affected by building *** a result,mass eccentricities must be taken into account in damper *** compared with vibrations induced by unidirectional excitations,bidirectional excitations can increase the responses of coupled asymmetric *** addition,installing dampers only at the top fl oor of the shorter building may cause a sudden change in lateral stiffness of the taller ***,the story shear envelopes of the taller building are changed.

关键词： bidirectional excitations connecting dampers adjacent buildings fractional derivative

Performance of Chemical Vapor deposited Boron-doped AlN Thin Film as Thermal Interface Materials for 3-W LEd: Thermal and Optical Analysis

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Acta Metallurgica sinica(English Letters) 2018年第1期31卷 97-104页

作者： s. shanmugan d. Mutharasu Nano Optoelectronics Research Laboratory School of Physics Universiti Sains Malaysia (USM) 11800 Minden Pulau Pinang Malaysia

Boron-doped aluminum nitride （B-AlN） thin films were synthesized on Al substrates by using chemical vapor deposition method by changing the synthesis parameters and were used as thermal interface material for high power light emitting diode （LEd）. The B-AlN thin film-coated Al substrate was used as heat sink and studied the performance of high power LEd at various driving currents. The recorded transient cooling curve was evaluated to study the rise in junction temperature （Tj）, total thermal resistance （gth_tot） and the substrate thermal resistance （Rth_sub） of the given LEd. From the results, the B-AlN thin film （prepared at process 4） interfaced LEd showed low Rth-tot and Tj value for all driving currents and observed high difference in Rth_tot （△Rth_tot =2.2 K/W） at 700 mA when compared with the Rth-tot of LEd attached on bare Al substrates （LEd/Al）. The Tj of LEd was reduced considerably and observed 4.7 ℃ as ATj for the film prepared using process 4 condition when compared with LEd/Al boundary condition at 700 mA. The optical performance of LEd was also tested for all boundary conditions and showed improved lux values for the given LEd at 700 mA where B-AlN thin film was synthesized using optimized flow of Al, B and N sources with minimized B and N content. The other optical parameters such as color correlated temperature and color rendering index were also measured and observed low difference for all boundary conditions. The observed results are suggested to use B-AlN thin film as efficient solid thin film thermal interface materials in high power LEd.

关键词： Light emitting diode (LEd) B-AIN thin film Chemical vapor deposition (CVd) Thermal transient analysis Junction temperature Optical performance

Combinatorial therapies for spinal cord injury repair

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Neural Regeneration Research 2025年第5期20卷 1293-1308页

作者： Carla s.sousa Andreia Monteiro António J.salgado Nuno A.silva Life and Health sciences Research Institute(ICVs) School of MedicineUniversity of MinhoCampus de Gualtar-gualtarBragaPortugal ICVs/3B’s Associate Lab PT Government Associated LabCampus de Gualtar-gualtarBragaPortugal

spinal cord injuries have profound detrimental effects on individuals, regardless of whether they are caused by trauma or non-traumatic events. The compromised regeneration of the spinal cord is primarily attributed to damaged neurons, inhibitory molecules, dysfunctional immune response, and glial scarring. Unfortunately, currently, there are no effective treatments available that can fully repair the spinal cord and improve functional outcomes. Nevertheless, numerous pre-clinical approaches have been studied for spinal cord injury recovery, including using biomaterials, cells, drugs, or technological-based strategies. Combinatorial treatments, which target various aspects of spinal cord injury pathophysiology, have been extensively tested in the last decade. These approaches aim to synergistically enhance repair processes by addressing various obstacles faced during spinal cord regeneration. Thus, this review intends to provide scientists and clinicians with an overview of pre-clinical combinatorial approaches that have been developed toward the solution of spinal cord regeneration as well as update the current knowledge about spinal cord injury pathophysiology with an emphasis on the current clinical management.

关键词： electric stimulation neural tissue regeneration neuroprotection polytherapy spinal cord injury