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Recent progress of CERN 39-cryogenic tracking detectors collaboration

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中国有色金属学会会刊：英文版 2006年第B01期16卷 137-140页

作者： j.hrknen helsinki Institute of Physics CERN /EPCH-1211 GenevaSwitzerland

Significant progress was made by the CERN RD39 collaboration in the development of super radiation-hard cryogenic silicon detectors for applications in experiments at LhC, in particular after its future luminosity upgrade. The detailed modeling shows that the electric field in irradiated silicon detectors can easily be manipulated by the filling state of two deep defect levels at cryogenic temperature. Advanced radiation hard detectors using charge or current injection and the current injected detectors(CID) were developed by RD39. The results show that CID detectors can be operated at the temperature of 100?200 K with much improved charge collection efficiency(CCE) as compared with RT operation. Future studies are developing ultra-hard cryogenic silicon detectors for the LhC upgrade, where the radiation hardness is required up to 1016 neq/cm2, at which trapping will limit the charge collection depth to the range of 20 to 50 μm regardless of the depletion depth. The key of our approach is to use freeze-out trapping to affect CCE.

关键词：欧洲原子能研究机构 CERN39协作组低温跟踪俘获粒子探测器研究进展

Shell biorefinery: A comprehensive introduction

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Green Energy & Environment 2018年第4期3卷 318-327页

作者： Max j.hlsey Department of Chemical and Biomolecular Engineering National University of Singapore

Biomass refinery is considered to be a key technology in the 21 st century due to the importance of the sustainable production of various bioderived fuels and fine chemicals. Besides the synthesis of oxygen-containing chemicals mainly from lignocellulosic biomass, nitrogencontaining chemicals belong to some of the most important commodity and fine chemicals. In this introductory short review, the main similarities and difficulties between petroleum oil-and biorefinery will be discussed and future challenges will be highlighted. As a particular example, recent developments in the shell biorefinery – the utilization of shell waste – will be reviewed. Particular emphasis will be placed on the structure of shell biomass, the current and emerging fractionation methods and the conversion of chitin and chitosan to various heteroatomcontaining chemicals. This review is meant to provide an introduction to beginners in the field of biorefinery as well as a comprehensive discussion of recent proceedings in the field of shell biorefinery. An outlook on the future potential and challenges will be given.

关键词： Shell biorefinery

Prediction of protein and amino acid composition and digestibility in individual feedstuffs and mixed diets for pigs using near-infrared spectroscopy

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Animal Nutrition 2021年第4期7卷 1242-1252页

作者： Samantha j.Noel henry j.høgh jørgensen Knud E.Bach Knudsen Department of Animal Science AU FoulumAarhus UniversityDK 8830TjeleDenmark

Knowledge of the amounts and digestibility of amino acids in pig feedstuffs is essential for calculating the appropriate inclusion level in a complete *** chemical analysis and in vivo digestibility trials are time-consuming and costly and cannot be used for routine ***-infrared spectroscopy(NIRS)offers a rapid,cost effective and environmentally friendly method for evaluating *** models were developed using NIRS to predict the content of crude protein and 18 amino acids from a wide range of feedstuffs used in pig production(n=607).The samples ranged from single feed ingredients(containing amino acids from 0.3 to 129.8 g/kg of dry matter)to feed mixtures(containing amino acids from 1.2 to 53.2 g/kg of dry matter).The predictive ability of the calibrations was tested with an independent dataset(n=150)and with ***,we compare these calibrations with calibrations developed on more narrowly defined groups of samples and with predictions from regression analysis of crude *** models were able to predict the concentrations of crude protein and 18 amino acids with good levels of precision and high coefficients of determination for calibration(RSQ^(CAL))from 0.91 to 0.99 and validation(RSQ^(VAL))from 0.87 to *** models were able to predict all amino acids except tryptophan and valine with greater accuracy than those from protein *** also developed calibration models to predict the apparent ileal and total tract digestibility of protein and amino *** the exception of tryptophan,RSQ values(>0.7)and standard error of cross validation(SECV)values(he digestibility of most of the amino *** conclusion,NIRS can be used to predict crude protein and amino acid concentrations from a wide range of single ingredients and feed mixtures used for pig diets without separate models for each *** digestibility of protein and amino acids can be predicted with an

关键词： Near-infrared spectroscopy Amino acids Protein Apparent ileal digestibility Total tract digestibility Swine

Fe-Si droplets associated with graphite on blast furnace coke

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International journal of Minerals,Metallurgy and Materials 2012年第6期19卷 478-482页

作者： Stanislav S.Gornostayev Timo M.j.Fabritius Olavi Kerkkonen jouko j.hrkki Laboratory of Process Metallurgy University of OuluOulu 90014Finland Ruukki Metals Oy Raahe 92102Finland

Fe-Si droplets on the surface of blast furnace （BF） coke from 25 to 50 cm at the tuyere level are mostly composed of Fe3Si, which has various shapes （round, elongated, and irregular） and penetration degrees into the BF coke matrix. The shapes and penetration degrees may depend on the saturation of molten iron by silicon during interaction with the coke matrix. The droplets are covered by a tiny shell of carbon. Graphite observed inside the droplets can be divided into two categories： well-formed tabular crystals with relatively large size and flakes with structures similar as those in cast iron. The textures of the droplets reflect composition, interaction with the coke matrix, and cooling conditions.

关键词： metallurgical coke graphite iron blast furnaces

X38CrMoV5 hot-work tool steel as tool material for thixoforging of steel:Numerical and experimental evaluation

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中国有色金属学会会刊：英文版 2010年第S3期20卷 713-718页

作者： A.RASSILI j.C.PIERRET G.VANEETVELD j.h ALLEUX G.WALMAG j.LECOMTE-BECKERS Thixo Unit ULg Department of Aerospace and Mechanica l EngineeringUniversity of Liège

Although thixoforming of low melting point alloys as aluminum or magnesium is now an industrial reality,thixoforming of high melting point alloys as steel is still at the research *** working temperature,die wearing and production rate are problems that must be solved and are under *** aim of this work is to evaluate the thermal and mechanical loadings applied to the tools during the steel thixoforging process in order to determine whether classical hot-work tool steel can be an appropriate tool *** evaluation has been realized thanks to experimental trials and to simulations on the finite elements code Forge2008.The effect of the loadings on the tool's failure modes are highlighted and compared with the ones observed in classical hot *** this,the failure modes of hot-work tool steel,the X38CrMoV5 or h11,were presented.

关键词： thixoforging steel high melting point tool material

ELECTRONIC STRUCTURES OF (CdSe)_n/(ZnSe)_m STRAINED-LAYER SUPERLATTICES

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Acta Metallurgica Sinica(English Letters) 1997年第1期10卷 10-16页

作者： hL. huang j.h Xing G.L. Liu and G.Y Zhang(Department of Electrouic Science and Engineering, Liaoning University Shenyang 110036, China)(Department of Physics, Liaoning University Shenyang 110036, China)(Shenyang Polytechnic University Shenyan 110023, Chin Liaoning Univ Shenyang China

The electronic structures of (CdSe)n/(ZnSe)m strained-lager soperfattice (SLS) were investigated by the recursion method in the tight-bindiop opproximation. The total,local, and partial density of states were calculated for n=1, m=*** total density of states (TDOS) for bulk CdSe, ZnSe and n=1, 3, m=1, 3, 5, for SLS were *** energy, the band gap, the valence of an atom, and the ionization potential and the electron affinity were discassed.

关键词： density of state strained layer superlattice CdSe/ZnSe Fermi energy band gap

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn j.W.So Konstantin Feinberg Marina Manoraj jenny Cheung jennifer Zhang Kaveh Mirmoeini jPaul Santerre Tessa Gordon Gregory hBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

EXAFS study of cation reordering in NaYF_4:Yb^(3+),Tb^(3+) up-conversion luminescence materials

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journal of Rare Earths 2014年第3期32卷 226-229页

作者： h.F.Brito j.hls T.Laamanen T.Laihinen M.Lastusaari L.Pihlgren L.C.V.Rodrigues T.Soukka Instituto de Química Universidade de S?o Paulo Department of Chemistry University of Turku Turku University Centre for Materials and Surfaces (MatSurf) Department of Chemistry University of Turku FI-20014 Turku Finland Turku University Centre for Materials and Surfaces (MatSurf) Turku Finland University of Turku Graduate School (UTUGS) Doctoral Programme in Physical and Chemical Sciences Graduate School of Materials Research (GSMR) Department of Biochemistry University of Turku

The NaYF4：yb3＋,Tb3＋（Xyb： 0.20, XTb： 0.04） materials were prepared using the co-precipitation method, lne as-preparea material was washed either with or without water in addition to ethanol and thereafter annealed for 5 h at 500℃. This resulted in materials with moderate or very high up-conversion luminescence intensity, respectively. The structural study carried out with X-ray powder diffraction revealed microstrains in the rare earth （R） sublattice that were relaxed for the material with very high up-conversion intensity thus decreasing energy losses. The local structural details were investigated with R LⅢ and Y K edge ex- tended X-ray absorption fine structure （EXAFS） using synchrotron radiation. Around 10 tool.% of the Yb3＋ ions were found to occupy the Na site in the material with very high up-conversion intensity. These Yb species formed clusters with the Tb3＋ ions occupying the regular Na/R sites. Such clustering enhanced the energy transfer between Yb3＋ and Tb3＋ thus intensifying the up-conversion emission.

关键词： EXAFS up-conversion ytterbium terbium cation reordering

A STUDY OF CARBIDE GROWTh IN MAR-M247 LC ALLOY BY DIRECTIONAL SOLIDIFICATION METhOD

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 509-514页

作者： j.h Lee j. Chen S.j. Choe Y.T. Lee and h.M. Kim(high Temperature Materials Laboratory, Korea Institute of Machinery & Materials, 66 Sangnam Dong,Changwon, Kyungnam,641010, Korea ) Korea Inst of machinery & Materials Changwon South Korea

The carbide growth behavior of MAR-M247 LC alloy was investigated by directional solidification and quench method. The carbide volume fraction, trapping and growth behavior were correlated with the growth *** was found that the carbide volume fraction decreased at slower growth *** decreasing was caused by lower solidliquid interface trapping ability at slower growth rate.

关键词： carbide,directional solidification,trapping growth