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Nano Research 2019年第9期12卷 2373-2377页

作者： Virginia l. j.hnson Auddy Anilao Kristie j. Koski Department of Chemistry University of CaliforniaDavisDavisCA 95616USA

Two-dimensional(2D)layered silicon telluride(SizTes)nanocrystals were compressed to 12 GPa using diamond anvil cell *** measurements show a color change from transparent red to opaque black indicating a semiconductor-to-metal phase *** scattering was used to observe the stiffening of the crystal lattice and subsequent phase behavior.A possible phase transition was *** 9.5±0.5 GPa evidenced by the disappearance of the Atg stretching *** was intercalated with elemental manganese to^1 at.%.Intercalation lowers the pressure of the proposed phase transition to 7.5±1 *** modes show both phonon stiffening and phonon softening,suggesting negative linear *** results provide fundamental insight into the high-pressure optical phonon behavior of silicon telluride and illuminate how a specific electron-donating intercalant can chemically alter pressure-dependent optical phonon behavior.

关键词： silicon telluride Si2Te3 high pressure diamond anvil cell two-dimensional(2D)layered material

Preparation of neodymium-doped yttrium aluminum garnet powders and fibers

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j.urnal of Rare Earths 2008年第5期26卷 670-673页

作者： R. lópez j. Zárate E. A. Aguilar j. Muoz-Saldaa Instituto de Investigaciones Metalurgicas UMSNH Morelia Centro de Investigación y de Estudios Avanzados del IPN Unidad Queretaro

Using nitrate precursors, a novel spray-drying assisted citrate gel process for the preparation of neodymium-doped yttrium alumi- num garnet （YAG） phase was developed. Synthesis of single-phase polycrystalline YAG was achieved at temperatures as low as 800 ℃ using the spray-drying methodology whilst conventional approaches currently available require 1000 ℃. Initially, a solution was prepared by mixing aluminum and yttrium nitrates, citric acid, etilenglycol and neodymium oxide. This solution was dried by pulverization （spray dryer） to obtain aggregated precursor powders of the compound. These aggregates were calcined at 800, 850 and 900 ℃ to determine the phase evolution from amorphous to crystalline by X-ray diffraction （XRD）. The morphology of aggregates was characterized by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Moreover, through XRD it was determined that the crystallization of YAG phase started at about 800 ℃ without any intermediate phases. The powders were composed of spherical aggregates with an average diameter of 1 um. From these powders, ceramic fibers with additions of 2at.% and 5at.% Nd, were extracted from the melt with diameters ranging from 30 um to 50 um.

关键词： spray-drying melt extraction fibers yttrium aluminum garnet rare earths

Formation of High-quality Advanced High-k Oxide layers at low Temperature by Excimer UV lamp-assisted Photo-CVD and Sol-gel Processing

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Chemical Research in Chinese Universities 2004年第4期20卷 396-402页

作者： YU j. j. Electronic & Electrical Engineering University College London

We have successfully demonstrated that high quality and high dielectric constant layers can be fabricated by low temperature photo-induced or -assisted processing. Ta_2O_5 and ZrO_2 have been deposited at tl-gel processing with the aid of excimer lamps. The UV annealing of as-grown layers was found to significantly improve their electrical properties. low leakage current densities on the order of 10 -8 A/cm 2 at 1 MV/cm for deposited ultrathin Ta_2O_5 films and ca.10 -6 A/cm 2 for the photo-CVD ZrO_2 layers and photo-irradiated sol-gel HfO_2 layers have been readily achieved. The improvement in the leakage properties of these layers is attributed to the UV-generated active oxygen species O( 1D) which strongly oxidize any suboxides to form more stoichiometric oxides on removing certain defects, oxygen vacancies and impurities present in the as-prepared layers. The photo-CVD Ta_2O_5 films deposited across 10.16-cm Si wafers exhibit a high thickness uniformity with a variation of less than \{±2.0%\} being obtained for ultrathin ca.10 nm thick films. The lamp technology can in principle be extended to larger area wafers, providing a promising low temperature route to the fabrication of a range of high quality thin films for future UlSI technology.

关键词： Excimer lamp High-kdielectrics Thin film Chemical vapour deposition(CVD) Sol-gel processing

Brain-penetrating neurotrophic factor mimetics: HER-096 as a disease-modifying therapy for Parkinson’s disease

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Neural Regeneration Research 2025年第4期20卷 1094-1095页

作者： Natalia Kulesskaya Kira M.Holmström Henri j.Huttunen Herantis Pharma Plc EspooFinland

Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A maj.r unmet need in the field of central nervous system diseases is disease-modifying *** for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,*** that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.

关键词： diseases treatment therapeutic

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy inj.ries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha j.Holdsworth Alistair j.Gunn laura Bennet Hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy inj.ries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain inj.ry may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

Experimental study on the wear evolution of different PVD coated tools under milling operations of lDX2101 duplex stainless steel

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Advances in Manufacturing 2023年第1期11卷 158-179页

作者： Vitor F.C.Sousa Francisco j.G.Silva Ricardo Alexandre j.se S.Fecheira Gustavo Pinto Andresa baptista ISEP-School of Engineering Polytechnic of PortoRua Dr.António Bernardino de Almeida4314200–072PortoPortugal INEGI-Driving Science and Innovation Rua Dr.Roberto Frias4004200–465PortoPortugal TEandM-Technology Engineering and MaterialsS.A.Parque Industrial do TaveiroLotes 41-423045–504TaveiroPortugal

Duplex stainless steels are being used on applications that require,especially,high corrosion resistance and overall good mechanical properties,such as the naval and oil-gas exploration *** components employed in these industries are usually obtained by machining,however,these alloys have low machinability when compared to conventional stainless *** this work,a study of the wear developed when milling duplex stainless-steel,lDX 2101,is going to be presented and evaluated,employing four types of milling tools with different geometries and coatings,while studying the influence of feed rate and cutting length in the wear of these *** used have been provided with two and four flutes,as well as three different coatings,namely:TiAlN,TiAlSiN and *** cutting behavior of these tools was analyzed;data relative to the cutting forces developed during the process were obtained;and roughness measurements of the machined surfaces were *** tools were then submitted to scanning electron microscope(SEM)analysis,enabling the identification of the wear mechanisms that tools were subj.cted to when machining this material,furthermore,the early stages of these mechanisms were also *** this work was done with the goal of relating the machining parameters and cutting force values obtained,identifying,and discussing the wear patterns that were observed in the coating and tools after the milling tests,providing further information on the machining of these alloys.

关键词： Duplex stainless-steel Milling Tool coatings Surface roughness Wear mechanisms

Active explosion barrier performance against methane and coal dust explosions

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International j.urnal of Coal Science & Technology 2015年第4期2卷 261-268页

作者： j. j. l. du Plessis Department of Mining Engineering University of PretoriaPretoria 0028 South Africa

Preventing the propagation of methane or coal dust explosions through the use of active explosion-suppression systems remains one of the most underutilised explosion controls in underground coal mines. As part of the effort to develop better technologies to safeguard mines, the use of active barrier systems was investigated at Kloppersbos in South Africa. The system is designed to meet the requirements of the European Standard （EN 14591-4 2007） as well as the Mine Safety Standardisation in the Ministry of Coal Industry, Coal Industrial 1 Standard of the Peoples Republic of China （MT 694-1997）. From the tests conducted, it can be concluded that the ExploSpot System was successful in stopping flame propagation for both methane and methane and coal dust hybrid explosions when ammonium phosphate powder was used as the suppression material. The use of this barrier will provide coal mine management with an additional explosion control close to the point of ignition and may find application within longwall faces further protecting mines against the risk of an explosion propagating throughout a mine.

关键词： Coal Methane Explosions Active barriers

自发熔渗法制备TiC/NiAl复合材料和其微观组织特征

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复合材料学报 2004年第5期21卷 11-15页

作者：高明霞潘颐 F.j.OlIVERIA j.l.baptista j.M.VIEIRA 浙江大学材料科学与工程学系杭州310027 葡萄牙阿威罗大学陶瓷与玻璃工程系阿威罗3810193

用自发熔化渗透法制备高TiC含量 (～ 75vol% )的TiC/NiAl复合材料 ,研究了渗透温度和渗透时间对TiC/NiAl复合材料微观组织形成、硬度及断裂性能的影响。采用XRD和TEM /EDS分析了复合材料的相组成、微观结构和NiAl相与TiC颗粒在高温渗透... 详细信息

用自发熔化渗透法制备高TiC含量 (～ 75vol% )的TiC/NiAl复合材料 ,研究了渗透温度和渗透时间对TiC/NiAl复合材料微观组织形成、硬度及断裂性能的影响。采用XRD和TEM /EDS分析了复合材料的相组成、微观结构和NiAl相与TiC颗粒在高温渗透过程中的互溶情况。结果表明 :自发熔渗法是制备致密的TiC/NiAl复合材料的有效方法 ,适当提高渗透温度 ,可大大缩短渗透时间。在完成渗透获得致密组织的前提下 ,渗透温度和渗透时间对TiC/NiAl复合材料的硬度及断裂韧性无显著影响。NiAl相和TiC颗粒结合良好 ,是渗透后复合物的仅有组成相。TiC少量地溶于NiAl,溶解度随渗透时间增长而增大 ,且在TiC颗粒外层 ,发现有少量的Al和微量的Ni。

关键词：熔化渗透复合材料微观组织碳化钛镍铝金属间化合物

Animal models of melanoma: a somatic cell gene delivery mouse model allows rapid evaluation of genes implicated in human melanoma

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Chinese j.urnal of Cancer 2011年第3期30卷 153-162页

作者： Andrea j. McKinney Sheri l. Holmen Department of Drug and Target Discovery Nevada Cancer Institute

The increasing incidence and mortality associated with advanced stages of melanoma are cause for concern. Few treatment options are available for advanced melanoma and the 5-year survival rate is less than 15%. Targeted therapies may revolutionize melanoma treatment by providing less toxic and more effective strategies. However, maximizing effectiveness requires further understanding of the molecular alterations that drive tumor formation, progression, and maintenance, as well as elucidating the mechanisms of resistance. Several different genetic alterations identified in human melanoma have been recapitulated in mice. This review outlines recent progress made in the development of mouse models of melanoma and summarizes what these findings reveal about the human disease. We begin with a discussion of traditional models and conclude with the recently developed RCAS/TVA somatic cell gene delivery mouse model of melanoma.

关键词：黑色素瘤小鼠模型基因传递人类疾病体细胞快速评估动物模型治疗方案

Small extrachromosomal circular DNA in amyotrophic lateral sclerosis matter

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Neural Regeneration Research 2025年第5期20卷 1411-1413页

作者： Marcos j.Arauzo-Bravo Daniela Gerovska Matthias Schwab Alexandra Kretz Computational Biology and Systems Biomedicine Biodonostia Health Research InstituteSan SebastianSpain Basque Foundation for Science IKERBASQUEBilbaoSpainMax Planck Institute for Molecular BiomedicineComputational Biology and Bioinformatics GroupMünsterNorth Rhine-WestphaliaGermany Department of Cell Biology and Histology Faculty of Medicine and NursingUniversity of Basque Country(UPV/EHU)LeioaSpain Department of Neurology Jena University HospitalJenaThuringiaGermany

Comprehensive studies identify motor neuron spectrum disorders including amyotrophic lateral sclerosis(AlS)as globally rising fatal disorders with the highest prevalence in aging populations,influenced by ethnicity and ancestry(GBD 2016 Motor Neuron Disease Colla borators,2018).While~10% of diagnoses involve a family history(fAlS),most cases are considered sporadic(sAlS).However,population-based studies suggest that even cases without a common index mutation impart heritability(Ryan et al.,2019),indicating a crucial role of rare and as yet unknown genetic denominators.

关键词： amyotrophic sclerosis