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Journal of Materials Science & Technology 2014年第7期30卷 649-655页

作者： z.Y.Liu b.L.Xiao W.G.Wang z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences Dalian University of Technology Liaoning Shihua University

A route combining powder metallurgy and subsequent friction stir processing was utilized to fabricate carbon nanotube （CNT） reinforced AI （CNT/AI） and 6061AI （CNT/6061AI） composites. Microstructural observations indicated that CNTs were uniformly dispersed in the matrix in both CNT/AI and CNT/6061AI composites. Mg and Si elements tended to segregate at CNT-AI interfaces in the CNT/6061AI composite during artificial aging treatment. The tensile properties of both the AI and 6061AI were increased by CNT incorporation. The electrical conductivity of CNT/AI was decreased by CNT addition, while CNT/6061AI exhibited an increase in electrical conductivity due to the Mg and Si segregation.

关键词： Carbon nanotubes Metal matrix composites Mechanical properties Electrical properties Friction stir processing

brazilian payment for environmental services programs emphasize water-related services

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International Soil and Water Conservation Research 2023年第2期11卷 276-289页

作者： Ingrid Mamedes angélica Guerra Dulce b.b.Rodrigues Letícia Couto Garcia Raquel de Faria Godoi Paulo Tarso S.Oliveira Faculty of Engineering Architecture and Urbanism and GeographyFederal University of Mato Grosso do SulMS79070-900Brazil Programa de Pós-Graduaçāo em Ecologia e Conservaaçāo Universidade Federal de Mato Grosso do SulCampo GrandeBrazil Laboratorio de Ecologia da Intervenaçāo-LEl Instituto de BiociênciasUniversidade Federal de Mato Grosso do SulCampo GrandeBrazil Department of Hydraulics and Sanitary Engineering Sao Carlos School of EngineeringUniversity of Sao PauloSao CarlosSPBrazil

based on"user pays"and"provider gets"principles,the Payment for Environmental Services(PES)consists of providing economic incentives or compensation for land users who adopt activities that promote ecosystem *** PES initiatives have grown rapidly in brazil over the last few decades,however,studies that address the panorama of these programs in the country are still scarce,regional,or ***,we investigate the PES overview in brazil through interviews and an extensive literature *** found in total 80 PES programs implemented in brazil,of which 14 were *** pro-grams are poorly distributed across the country,mostly concentrated in the Atlantic Forest(56.25%)and Savanna(36.25%)biomes,in Southeastern *** majority of programs primarily prioritize improving water quality and ***,reforestation,protection of native vegetation,and soil and water conservation are their main proposed *** positive impacts of brazil's PES experi-ences are evident;while the lack of transparency and monitoring,and poor spatial and financial dis-tribution are still major *** conclude that if correctly implemented,PES schemes offer a path to reconcile environmental conservation with agricultural production in brazil.

关键词： Conservation funding Ecological restoration Environmental compliance Public policy Soil and water conservation

A STUDY ON AGING TREATMENTS FOR ALLOY 2195

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 45-50页

作者： b.P.Huang z.Q.zheng Central South Univ of Technology Changsha China

Effects of various aging treatments on mechanical properties and microstructure of alloy 2195 have been investigated. The experimental results showed that a promising combination of strength and ductility was achievable under T8 temper. The lower aging temperature reduced subgrain-or grain-boundary T1 precipitation and favored uniform dispersion of T1 phases, resulting in better strength and ductility. Prior deformation improved aging strength with promising ductility. Pre-aging after prior deformation had little effect on the age-hardening behavior of alloy 2195.

关键词： Al alloy 2195,aging mechanical property microstructure

One-Dimensional Anyon Lattice and slq（2） Algebra Realization

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Chinese Physics Letters 2005年第5期22卷 1207-1209页

作者： z.bentalha M.Tahiri b.Liani TheoreticalPhysicsLaboratory TlemcenUniversityTlemcenAlgeria LaboratoiredePhysiqueThéorique Universitéd'Essenia31100OranAlgeria

We discuss the connection between anyons (particles with fractional statistics) living on a one-dimensional lattice and slq(2) algebra. We assign to each site-anyon field, then we demand the anyonic fields to be noncommuting objects in agreement with the Chern–Simons picture of anyons. We show how the anyonic algebra can emerge from these noncommuting objects. Starting from the emerged algebra we build the slq(2) algebra at q roots of unity.

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PREPARATION AND XRD STUDY OF LITHIUM DEFICIENT Lib COMPOUND

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 667-671页

作者： z.J.Liu b.Y.Huang z.Y.Li StateKeyLaboratoryforPowderMetallurgy CentralSouthUniversityChangsha410083China

The Lib compounds in lithium deficient state were prepared by three methods and its crystal structure was investigated by using XRD. It is found that the lattice constant c of the compound will increase step by step with decreasing Li content from 0.2796nm of the normal Lib to 0.2886, 0.2981 and 0.3118nm of the lithium deficient Lib. The change of the lattice constant is reversible.

关键词： Lib compound crystal structure electrode materials X-ray diffraction

Modelling of a Multi-Temperature Plasma Composition

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Chinese Physics Letters 2005年第12期22卷 3119-3122页

作者： b. Liani R. benallal z. bentalha Laboratoire Physique Théorique B.P. 119 Bel Horizon 13000 Tlemcen Algérie

Knowledge of plasma composition is very important for various plasma applications and prediction of plasma properties. We use the Saha equation and Debye length equation to calculate the non-local thermodynamic-equilibrium plasma composition. It has been shown that the model to 2T with T representing the temperature （electron temperature and heavy-particle temperature） described by Chen and Han [J. Phys. D 32 （1999）1711] can be applied for a mixture of gases, where each atomic species has its own temperature, but the model to 4T is more general because it can be applicable to temperatures distant enough of the heavy particles. This can occur in a plasma composed of big- or macro-molecules. The electron temperature Te varies in the range 8000＊20000K at atmospheric pressure.

关键词： 2-TEMPERATURE PLASMA SCATTERING

An Aluminide Surface Layer Containing Lower-Al on Ferritic-Martensitic Steel Formed by Lower-Temperature Aluminization

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Journal of Materials Science & Technology 2015年第12期31卷 1268-1273页

作者： S.Guo z.b.Wang K.Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

An aluminide（AlFe and α-（FeAl）） surface layer containing lower-Al was formed on ferritic-martensitic steel P92 by means of surface mechanical attrition treatment（SMAT） combined with a duplex aluminization process at lower temperatures,i.e.a packed aluminization followed by a diffusion annealing treatment below its tempering *** tests indicated that the lower-Al surface layer formed on the SMAT sample is more resistant to cracking and has better adhesion to the substrate in comparison with the Al 5Fe 2 layer formed on the as-received sample after the duplex aluminization *** steam oxidation measurements showed that the oxidation resistance is increased significantly by the lower-Al surface layer due to the formation of a protective（Fe,Cr）Al 2O 4 *** rate constant of oxidation was estimated to decrease from-0.849 mg^2 cm^-4h^-1 of the as-received material to^0.011 mg^2 cm^-4 h^-1 of the AlFe layer at 700 ℃.

关键词： Surface mechanical attrition treatment (SMAT) Ferritic-martensitic steel Lower-temperature aluminization Aluminide Steam oxidation

Influencing mechanism of pre-existing nanoscale Al5Fe2 phase on Mg-Fe interface in friction stir spot welded Al-free zK60-Q235 joint

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Journal of Materials Science & Technology 2020年第7期42卷 220-228页

作者： R.z.Xu Q.Yang D.R.Ni b.L.Xiao C.z.Liu z.Y.Ma Institute of Metal Research Chinese Academy of SciencesShenyang110016China College of Material Science and Engineering Shenyang Aerospace UniversityShenyang110136China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign1304 W Green StUrbanaIL61801United States Fredrick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign104 S Goodwin AveUrbanaIL61801United States

Al-free zK60 magnesium (Mg) alloy sheet was selected as substrate material of Mg-steel pinless friction stir spot welding (FSSW), avoiding the effect of the Al element in the substrate on the alloying reaction of Mg-iron (Fe) interface. The sound FSSW joint of zK60 Mg alloy and Q235 steel with a hot-dipped aluminum (Al)-containing zinc (zn) coating was successfully realized. The detailed microstructural examinations proved that Al5Fe2 phase at the Mg-Fe interface came from the pre-existing Al5Fe2 phase in the coating and acted as the transition layer for promoting the metallurgical bonding of Mg and Fe. The interfaces with well-matched lattice sites among Fe, Al5Fe2 and Mg were formed during FSSW. A low energy interface with good match of lattice sites ((002)Al5Fe2//(110)Fe, [110]Al5Fe2//[113]Fe) between Al5Fe2 and Fe was identified. For the interface between Al5Fe2 and Mg, an orientation relationship of (622)Al5Fe2//(3112)Mgand[158]Al5Fe2//[2423]Mg was observed. The tensile-shear load of the zK60-steel joint could reach 4.6 kN. Moreover, the joint fracture occurred at the interface between the Al5Fe2 layer and the Mg alloy substrate, suggesting the brittle fracture characteristic.

关键词： Dissimilar welding Friction stir spot welding Magnesium alloys Steels zinc coating

Fast frequency-domain equalization for single-carrier V-bLAST systems over multipath channel

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Science in China(Series F) 2009年第1期52卷 115-125页

作者： FENG ang YIN QinYe FAN JianCun School of Electronics and Information Engineering Xi'an Jiaotong University Xi'an 710049 China

A low complex minimum mean-square error frequency-domain decision feedback （MMSE-FDDF） equalization algorithm is proposed in this paper for the single-carrier V-bLAST systems. Exploiting the factor that the discrete Fourier transform （DFT） is unitary, the proposed receiver can equalize the signals by the MMSE detecting to the spectrums in the frequency domain instead of the waveforms in the time domain. In order to obtain the right decisions, the detector must be able to equalize the overall spectrum with regard to each layer. This work can be performed very efficiently since the system matrix has been designed as a special block-circulant-block matrix. Similar to other V-bLAST-like systems, the detecting order has strong impact on the performance of MMSE-FDDF. Therefore, we further give a fast optimally sorting scheme for the MMSE-FDDF architecture. by using the newly constructed matrix, the coefficients computation and the sorting can be combined into one process, and then we employ the modified Gram-Schmidt （MGS） to simplify the process. The simulation results and the computational complexity analysis show that the proposed MMSE-FDDF has better tradeoff between the performance and the complexity than the existing algorithms. In addition, MMSE-FDDF can avoid the performance floor caused by the overlap-and-save technique in the severe dispersive channel.

关键词： single-carrier orthogonal frequency division multiplexing frequency domain equalization V-bLAST ordering Cholesky decomposition

Prognostic effect analysis of molecular subtype on young breast cancer patients

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Chinese Journal of Cancer Research 2015年第4期27卷 428-436页

作者： Hong-Liang Chen ang Ding Fu-Wen Wang Department of breast Surgery Obstetrics and Gynecology Hospital of Fudan University

Objective： To make a prognostic effect analysis of molecular subtype on young breast cancer ***： Totally 187 cases of young breast cancer patients less than 40 years old treated in Obstetrics and Gynecology Hospital of Fudan University between June 2005 and June 2011 were included in our study. We described their clinical-pathological characteristics, disease-free survival（DFS） rate, and overall survival（OS） rate after a median follow-up period of 61 months. The factors associated with prognosis were also evaluated by univariate and multivariate ***： All patients were premenopausal, with an average age of 35.36±3.88 years old. The mean tumor size was 2.43±1.53 cm. Eighty-one cases had lymph node metastasis（43.3%）, 126 cases had lymphovascular invasion（67.4%）, and 125 cases had histological grade III（66.8%） disease. Twenty-seven cases（14.4%） were Luminal A subtype, 99 cases（52.9%） were Luminal b subtype, 29 cases（15.5%） were human epidermal growth factor receptor 2（HER-2） overexpression subtype, while 32 cases（17.1%） were triple negative breast cancer（TNbC） subtype according to 2013 St Gallen expert consensus. One hundred and thirty-five cases underwent mastectomy whereas 52 cases had breast-conserving surgery. One hundred and seventy-eight cases underwent adjuvant or neoadjuvant chemotherapy. Recurrence or metastasis occurred in 29 cases, 13 of which died. The 5-year DFS and OS rates were 84% and 92%. Multivariate analysis showed that nodal status（P=0.041） and molecular subtype（P=0.037） were both independent prognostic factors of DFS, while nodal status（P=0.037） and TNbC subtype（P=0.048） were both independent prognostic factors of OS. Conclusions： Molecular subtype is an independent prognostic factor of young breast cancer patients. TNbC has a high risk of relapse and death.

关键词： Molecular subtype young breast cancer prognosis