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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 441-448页

作者： g.F.Liang C.Q.wan J.C.Wu g.M.Zhu y.yu y.Fang Advanced Technology Institute Technology Center of BaosteelShanghai 201900China Department of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200030China

It was presented the in situ observation of growth behavior and morphology of delta-ferrite as a function of solidification rate in an AISI304 stainless steel. The specimens have been solidified and observed using confocal scanning laser microscopy (CSLM). The δ-phase always appears like cells on the sample surface when critical supercooling occurs, during which the L→δ transformation starts. The solid-liquid (S-L) interface is found to be finger shaped and has no faceted shape. γ phase appears among δ grains due to partitioning of Ni into the melt during solidification, when solidification rate is higher. The mergence of observed δ cells is possible for the steel sample cooled at 7.5℃/min. The formation of dendrites can be observed on the free surface of the steel sample cooled at 150℃/min. The size of solidified delta grains decreases from 120 to 20-80μm, and the volume fraction of solidified austenite increases with increase in solidification rate from 7.5 to 150℃/min. The relation between the tip radius of δ cell and its growth rate is deduced, and the results agree with the experimental values.

关键词： stainless steel confocal scanning laser microscopy δ-ferrite in situ observation solidification

Terminalia arjuna bark extract attenuates picrotoxin-induced behavioral changes by activation of serotonergic,dopaminergic,gABAergic and antioxidant systems

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Chinese Journal of Natural Medicines 2017年第8期15卷 584-596页

作者： Chandra Sekhar y Phani Kumar g Anilakumar K.R. Applied Nutrition Division Defence Food Research LaboratoryDRDOMysore-570011KarnatakaIndia

Stress and emotion are associated with several illnesses from headaches to heart diseases and immune deficiencies to central nervous system. Terminalia arjuna has been referred as traditional Indian medicine for several ailments. The present study aimed to elucidate the effect of T. arjuna bark extract(TA) against picrotoxin-induced anxiety. Forty two male Balb/c mice were randomly divided into six experimental groups(n = 7): control, diazepam(1.5 mg·kg^(–1)), picrotoxin(1 mg·kg^(–1)) and three TA treatemt groups(25, 50, and 100 mg/kg). Behavioral paradigms and PCR studies were performed to determine the effect of TA against picrotoxin-induced anxiety. The results showed that TA supplementation increased locomotion towards open arm(EPM) and illuminated area(light-dark box test), and increased rearing frequency(open field test) in a dose dependent manner, compared to picrotoxin(P gel's conflict. PCR studies showed an up-regulation of several genes, such as BDNF, IP_3, D_2L, CREB, gABAA, SOD, gPx, and gR in TA administered groups. In conclusion, alcoholic extract of TA bark showed protective activity against picrotoxin in mice by modulation of genes related to synaptic plasticity, neurotransmitters, and antioxidant enzymes.

关键词： Anxiety Terminalia arjuna gene expression Picrotoxin Neurotransmitters LC-MS

An essential role for TAK1 in the contact hypersensitivity response

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Cellular & Molecular Immunology 2011年第4期8卷 315-324页

作者： yan g Zhao yunqi wang Weidong Hao yisong y wan Department of Toxicology School of Public HealthPeking UniversityBeijingChina Department of Microbiology and Immunology Lineberger Comprehensive Cancer CenterUniversity of North Carolina at Chapel HillNCUSA

Contact hypersensitivity(CHS)is a delayed-type hypersensitivity that can be induced by haptens,such as 2,4-dinitrofluorobenzene(DNFB).Innate and adaptive immunities are both important for the development of *** treat CHS-related diseases,such as allergic contact dermatitis,a disease prevalent in industrialized countries,ways of interfering with improper immune function during CHS responses need to be *** growth factor-b-activated kinase-1(TAK1),a member of mitogen-activated protein kinase kinase kinase family,is important for both innate and adaptive *** thus hypothesized that the CHS response could be inhibited by interfering with TAK1 *** a mouse model in which TAK1 deletion can be locally induced,we observed that TAK deficiency led to an impaired CHS response and was associated with defective T-cell expansion,activation and interferon(IFN)-c *** addition,we investigated the effect of deleting TAK1 specifically in dendritic cells(DC)on the CHS *** found that when TAK1 is deficient in DC,the CHS response was abolished and hapten-elicited T-cell responses were ***,this study demonstrates an essential role of TAK1 in the induction of CHS and suggests that targeting TAK1 could be a viable approach to treat CHS.

关键词： CHS DC 2,4-dinitrofluorobenzene(DNFB) TAK1

The use of feld programmable gate array(FPgA)in direct torque control of induction motor

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控制理论与应用（英文版） 2013年第4期11卷 642-650页

作者： y.Srinivasa Kishore BABU g.Tulasi Ram DAS Department of Electrical & Electronics Engineering Jawaharlal Nehru Technological University(College of Engineering) Jawaharlal Nehru Technological University

In this paper, the feasibility of embedding the direct torque control （DTC） of an induction machine into field programmable gate arrays （FPgA） is investigated. DTC of an induction machine is simulated in a MATLAB/Simulink environment using a Xilinx system generator. The resulting design has a flexible and modular structure where the designer can customize the hardware blocks by changing the number of inputs, outputs, and algorithm when it is compared to the designs implemented using classical microcontrollers and digital signal processors. With its flexibility, other control algorithms can easily be programmed and embedded into the FPgA. The above system has been implemented on Xilinx Spartan 3A DSP FPgA controller. Simulation and experimentation have been performed to prove the validity of the proposed methodology.

关键词： Direct torque control (DTC) Space vector pulse width modulation (SVPWM) System generator (Sg) Field programmable gate array (FPgA) Induction motor (IM)

DSC AND TEM STUDy OF ULTRA HIgH STRENgTH ALUMINUM ALLOy

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 554-559页

作者： g.S.Xie y.Zeng H.Ding Hunan Electric Power Test & Research Institute Changsha 410007 ChinaMaterial Department Central South University Changsha 410083 ChinaMaterial Department Wuhan University Wuhan 430072 China

In this paper, the effect of RRA treatment on the microstructure evolution of a high strength aluminum alloy was investigated using DSC, TEM and SADP technology. The results show that the precipitation resulting from RRA is extremely fine and distributed homogeneously in the grains, being slightly coarser and more stable than that of T6 temper. While, the grain-boundary precipitation is very close to that of the alloy at T73 temper, being coarse and discontinuous. High retrogression temperature and long retrogression time leads to a more stable microstructure after re-aging.

关键词： DSC TEM RRA Al-Zn-Mg-Cu alloy

Structural and optical studies of yb^(3+),Er^(3+) and Er^(3+)/yb^(3+) co-doped phosphate glasses

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Journal of Rare Earths 2013年第7期31卷 685-693页

作者： S.Hraiech M.Ferid y.guyot g.Boulon Physical Chemistry Laboratory of Mineral Materials and Their Applications National Center of Research in Materials ScienceTechnologic Park of Borj Cedria B.P.738020 SolimanTunisia Physical Chemistry of Luminescent Materials(LPCML) University of LyonClaude Bernard/Lyon 1 UniversityUMR 5620 CNRSLa Doua69622 VilleurbanneFrance

Phosphate glass samples with various yb2O3 and Er2O3 contents were synthesized by the conventional melt quenching technique and characterized by X-ray diffraction, IR absorption spectroscopy and Raman scattering spectroscopy. The absorption, emission spectra and fluorescence decay studies were carried out both at low and room temperatures. Results showed the existence of several sites occupied by the rare earth ions in the phosphate glass. Up-conversion and cooperative fluorescence were also discussed.

关键词： yb3+/Er3+ co-doped phosphate glass energy transfer upconversion co-operative fluorescence rare earths

INVESTIgATION ON HOT DUCTILITy AND STRENgTH OF CONTINUOUS CASTINg SLAB FOR AH32 STEEL

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 75-78页

作者： g. y. Li X.F. Li L.g. Ao Technology Center Anshan Iron and Steel Group CorporationAnshan 114009 China

By means of gleeble-1500 testing machine, the simulation of continuous casting process forAH32 steel was carried out and hot ductility and strength were determined. The cracking sensitivity was studied under the different temperatures and strain rates. The Precipitations of AIN at different temperatures and the fractures of high-temperature tensile samples were observed by using TEM （transmission electron microscope） and SEM （scanning electron microscope）. The factors affecting the brittle temperature zone were discussed.

关键词： continuous casting slab brittle temperature zone tensile strength,ductility simulation

RELATIONSHIP AMONg EVAPORATION FLUX OF gROUNDwaTER, DEPTH OF waTER TABLE AND NEgATIVE PRESSURE HEAD IN BARE SOIL

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Journal of Hydrodynamics 2000年第4期12卷 52-58页

作者： Qian, J.Z. Zhu, X.y. Zhou, N.Q. Li, g.y. Dep. of Earth Sci. Nanjing Univ. Nanjing 210093 China

Evaporation of ground water is a part of moisture circulation in the field. And it is a main natural form in which water transmits from the ground water to the soil water and atmosphere water. According to the simulated experiments, we study the relationship among the evaporation, depth of groundwater table and negative pressure. By theoretical analysis of the experimental results, the main conclusions are drawn as follows. There are two abrupt points in every Q-H curve. The locations of the abrupt points are separately in step with the height of top of the capillary fringe and the height of maximal capillary rise in the soil section. When the depth of water table H is small, the evaporation flux of ground water is large. While the depth of water table exceeds the maximal capillary rise of media in vadose zone, the capillary rise breaks up and evaporation flux of groundwater is small. The water content ratio in ground surface tends to be zero and the surface of soil tends to be drought. These conclusions show that the maximal capillary rise of media in vadose zone is an important value in regulating rational depth of ground water to reduce the evaporation of ground water and to increase effective quantity of water resources. In the meantime, these conclusions are of important theoretical and practical significance to reduce the evaporation of ground water, to prevent and cure the salinization of soil, and to make full use of and protect water resources in the northern plains in China.

关键词： Capillarity Evaporation Soils

Large deformation and wrinkling analyses of bimodular structures and membranes based on a peridynamic computational framework

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Acta Mechanica Sinica 2019年第6期35卷 1226-1240页

作者： H.Li y.g.Zheng y.X.Zhang H.F.ye H.W.Zhang Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China International Research Center for Computational Mechanics State Key Laboratory of Structural Analysis for Industrial EquipmentDepartment of Engineering MechanicsFaculty of Vehicle Engineering and MechanicsDalian University of TechnologyDalian 116024China

In this paper,the quasi-static large deformation,wrinkling and fracture behaviors of bimodular structures and membranes are studied with an implicit bond-based peridynamic computational ***,the constant and tangential stiffness matrices of the implicit peridynamic formulations for the nonlinear problems are derived,*** former is con structed from the linearization of the bond strain on the basis of the geometric approximation while the latter is established according to the linearization of the pairwise force by using first-order Taylor’s ***,a bimodular material model in peridynamics is developed,in which the tensile or compressive behavior of the material at each point is conveniently described by the tensile or compressive states of the bonds in its ***,the bimodular material model is extended to deal with the wrinkling and fracture problems of membranes by setting the compressive micro-modulus to be *** addition,the incremental-iterative algorithm is adopted to obtain the convergent solutions of the nonlinear ***,several representative numerical examples are presented and the results demonstrate the accuracy and efficiency of the proposed method for the large deformation,wrinkling and fracture analyses of bimodular structures and membranes.

关键词： Bimodular structures Wrinkling membranes Fracture problems Peridynamics Implicit numerical algorithm

The biostimulative effectiveness of photobiomodulation therapy application on thawed dental pulp stem cells

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Journal of Innovative Optical Health Sciences 2021年第3期4卷 28-35页

作者： Cenk Serhan Özverel Aylin Ïslam Hasan güney yιlmaz Department of Basic Medical Sciences Faculty of Dentistry Near East UniversityNear East BoulevardNicosia 33000Mersin 10Turkey Department of Pediatric Dentistry Faculty of Dentistry Near East UniversityNear East BoulevardLefkosa 33000Mersin 10Turkey Department of Periodontology Faculty of Dentistry Near East UniversityNear East BoulevardLefkosa 33000Mersin 10Turkey The DESAM Institute Near East BoulevardLefkosa 33000Mersin 10Turkey

This study was conducted to understand the cellular proliferative effect of Photobiomodulation Therapy(PBMT)on thawed dental pulp stem cells(DPSCs)stored for 2 *** this purpose,cells were exposed to PBMT for short period of time to evaluate the most appropriate PBMT parameter for stimulating cellular proliferation that can be used for future tissue engineering *** characterized DPSCs were seperated into three groups according to the laser energy densities(5 J/cm^(2) or 7 J/cm^(2))applied and a group was served as control in which cells did not receive any laser *** cells in laser-irradiated groups were further divided into two subgroups according to the period of application(24 h and 0 h)and exposed to gallium-Aluminum-Arsenide diode laser *** viability and the proliferation rate of the cells were analyzed with the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide(MTT)assay,any PBMT related cellular cytotoxicity were determined by performing a lactate dehydrogenase assay(LDH)and statistical analysis of data were *** percentage of proliferation seemed to increase upon laser therapy in both different doses of irradiation(5 J/cm^(2) and 7 J/cm^(2)).DPSCs showed significantly higher proliferation rate upon 7 J/cm^(2) irradiation in both 0 h and 24 h when compared to control ***,DPSCs irradiated with 5 J/cm^(2) dose induced relatively lower proliferation rate when compared to 7 J/cm^(2) dose of *** to the LDH data,PBMT exposure did not show any significant cytotoxicity at both energy densities in all different time *** at 7 J/cm^(2) should be an effective parameter to stimulate proliferation of long-term cryopreserved DPSCs in a short term time *** therapy may be an upcoming tool for future tissue enngineering and regenerative dentistry applications.

关键词： PBMT tissue engineering proliferation short-term cytotoxicity