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Nanotexturing and Wettability Ageing of Polypropylene Surfaces Modified by Oxygen Capacitively Coupled Radio Frequency Plasma

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Journal of Materials Science & Technology 2014年第10期30卷 965-972页

作者： y.P.Li M.k.Lei Surface Engineering Laboratory School of Materials Science and EngineeringDalian University of Technology

Polypropylene （PP） was treated by an oxygen capacitively coupled radio frequency plasma （CCP） under a radio frequency （RF） power of 200 W for exposure time of 1, 5, and 10 rain. The ageing process of the plasma- treated PP was studied at an ageing temperature of 90 ~C during an ageing time up to 25 h. The formation of the nanotextures with different geometry and aspect ratio and the grafting of large number of oxygen- containing groups were achieved on as-treated PP surfaces under the oxygen CCP treatment for the increased exposure time. The hydrophilicity on the as-treated PP surfaces with the stable nanotextures was rapidly depressed during the ageing process at 90 ℃ due to the restructuring of chemical composition. The surface restructuring rate was dependent on the aspect ratio and the oxygen-containing groups on the nanotextured PP with increasing exposure time. The hydrophobic over-recovery to high hydrophobicity and superhydrophobicity were observed on the post-aged surfaces with the stable nanofibrils from as-treated hydrophilic surfaces. The superhydrophobicity with the low water adhesion was achieved on the post-aged surfaces preserving the nanofibrils with high aspect ratio and large distance due to the decrease of the oxygen-containing groups after the surface restructuring.

关键词： Polypropylene Plasma nanotexturing Ageing Surface restructuring Superhydrophobicity

Photoluminescence enhancement of red-emitting GdVO_4:Eu and yVO_4:Eu phosphors by adding zinc

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Journal of Rare Earths 2013年第1期31卷 13-17页

作者： k.Park J.kim k.y.kim J.y.kim y.kim S.J.Dhoble Faculty of Nanotechnology and Advanced Materials Engineering Sejong University Department of Advanced Materials Engineering Hoseo University Department of Chemistry and Institute of Basic Sciences Dankook University Department of Physics R.T.M. Nagpur University

We synthesized the rare-earth activated Ro.94_xEuo.06ZnxVO4 （R： Gd and y; 0〈_x〈_0.08） phosphors with a spherical mor- phology and a smooth surface by the ultrasonic spray pyrolysis. The annealed Ro.94_xEuo.06ZnxVO4 crystallized in the tetragonal zircon type structure, belonging to the space group of I41/amd. The incorporation of a small amount of Zn to Ro.94Euo.06VO4 improved the emission characteristics. The emission intensities of the Gdo.88EUo.06Zno.06VO4 and yo.9Euo.06Zno.04VO4 phosphors at 619 nm were 72% and 2 1% stronger than those of the Gdo,94Euo.06VO4 and yo.94Euo.06VO4 phosphors, respectively. We demonstrated that the addi- tion of Zn to Ro.94Euo.06VO4 was quite effective for improving the photoluminescent properties.

关键词： rare earths photolurninescence vanadate ultrasonic spray pyrolysis

Different effects of economic and structural performance indexes on model construction of structural topology optimization

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Acta Mechanica Sinica 2015年第5期31卷 777-788页

作者： G.L.yi y.k.Sui College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Department of Mechanical and Aerospace Engineering Seoul National University

The objective and constraint functions related to structural optimization designs are classified into economic and performance indexes in this *** influences of their different roles in model construction of structural topology optimization are also ***,two structural topology optimization models,optimizing a performance index under the limitation of an economic index,represented by the minimum compliance with a volume constraint（MCVC）model,and optimizing an economic index under the limitation of a performance index,represented by the minimum weight with a displacement constraint（MWDC）model,are *** on a comparison of numerical example results,the conclusions can be summarized as follows：（1）under the same external loading and displacement performance conditions,the results of the MWDC model are almost equal to those of the MCVC model;（2）the MWDC model overcomes the difficulties and shortcomings of the MCVC model;this makes the MWDC model more feasible in model construction;（3）constructing a model of minimizing an economic index under the limitations of performance indexes is better at meeting the needs of practical engineering problems and completely satisfies safety and economic requirements in mechanical engineering,which have remained unchanged since the early days of mechanical engineering.

关键词： Economic index Performance index Structural topology optimization models MCVC model MWDC model Safety and economy

HyBRID LINEAR AND QUADRATIC FINITE ELEMENT MODELS FOR 3D HELMHOLTZ PROBLEMS

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Acta Mechanica Solida Sinica 2013年第6期26卷 603-618页

作者： Q.H.Zhang k.y.Sze Guangdong Province key Laboratory of Computational Science Sun Yat-Sen University Department of Mechanical Engineering The University of Hong KongPokfulam

In this paper, linear and quadratic finite element models are devised for the three- dimensional Helmholtz problem by using a hybrid variational functional. In each element, contin- uous and discontinuous Helmholtz fields are defined with their equality enforced over the element boundary in a weak sense. The continuous field is based on the C° nodal interpolation and the discontinuous field can be condensed before assemblage. Hence, the element can readily be in- corporated seamlessly into the standard finite element program framework. Discontinuous fields constructed by the plane-wave, Bessel and singular spherical-wave solutions are attempted. Nu- merical tests demonstrate that some of the element models are consistently and considerably more accurate than their conventional counterparts.

关键词： finite element hybrid Helmholtz Bessel plane-wave spherical-wave radial basis function

NONLINEAR ANALySIS OF DyNAMIC STABILITy FOR LAMINATED CIRCULAR CyLINDRICAL THICk SHELLS WITH ENDS ELASTICALLy SUPPORTED AGAINST ROTATION

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Acta Mechanica Solida Sinica 1994年第1期7卷 15-28页

作者： y.k.CHEUNG y.M.Fu Department of Civil and Structural Engineering University of Hong kong Hong Kong Department of Engineering Mechanics Hunan University ChangshaP.R.China

Based on Timoshenko-Mindlin kinematic hypotheses and Hamilton's principle,a dynamic non-linear theory for general laminated circular cylindrical shells with transverse shear deformation is developed.A multi-mode solution for periodic in- plane loads is formulated for the non-linear dynamic stability of an anti-symmetric angle-ply cylinder with its ends elastically restrained against *** resulted equations in terms of time function are solved by the incremental harmonic balance method.

关键词： Hamilton's principle dynamic stability

Calcium signaling: the role of inositol phosphates and the mechanisms of Ca~(2+) entry

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中国药理学与毒理学杂志 1991年第4期5卷 246-254页

作者： Haruo TAkEMURA Chiu-yin kwan Oepartment of Pharmacology Sapporo Medical College S. 1 W. 17 Sapporo 060 Japan Smooth Muscle Research Program Department of Biomedical Sciences McMaster University Hamilton Ontario. Canada L8N 3Z5

Activation of surface membrane receptors provokes a variety of cellular responses by initiating a series of specific biochemical reactions which are responsible for the membrane transducing mechanisms and the subsequent Ca2+signaling process. Ca2+ is well known as a second messenger that an early consequence of receptor activation is usually the synthesis

关键词：药理学毒理学杂志

Clusterin mRNA expression in apoptotic and activated rat thymocytes

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Cell Research 2003年第1期13卷 49-58页

作者： JUNG-HyUNPARk,JEE-SUNPARk,SUNG-kyUJU,kwan-BOkLEE,kwan-HEEyOU,MyUNG-HEEkANG,yoo-kyOUNGPARk,SHIN-yOUNGNA Experimental Department Department Department Department Department Department Institute Immunology Branch National Cancer Institute NIH Bethesda MD 20892 USA of Biology College of Natural Science Chungnam National University 220 Gung-dong yuseong-gu Daejeon 305-764 korea of Biology College of Natural Science Chungnam National University 220 Gung-dong yuseong-gu Daejeon 305-764 korea of Biology College of Natural Science Chungnam National University 220 Gung-dong yuseong-gu Daejeon 305-764 korea of Biology College of Natural Science Chungnam National University 220 Gung-dong yuseong-gu Daejeon 305-764 korea of Food and Nutrition Hannam University Daejeon 306-791 korea of Food and Nutrition Hannam University Daejeon 306-791 korea for Virology and Immunobiology University of Wuerzburg Versbacher Str. 7 97078 Wuerzburg Germany

Clusterin is a 75-80 kDa heterodimeric glycoprotein, that is produced in most tissues but which exact biological role is still not clear. Particularly, its role in protection or promotion of apoptosis is heavily disputed, since data supporting both views have been reported in several independent studies. To clarify this issue, and also to determine whether clusterin expression itself might be affected by apoptosis, in the present study, rat thymocytes were treated with dexamethasone, -a synthetic glucocorticoid that elicits apoptosis in thymocytes-, and clusterin mRNA expression was analyzed by semi-quantitative RT-PCR before and after induction of apoptosis. Interestingly, neither the treatment with dexamethasone in vitro nor triggering of apoptosis in vivo up- regulated clusterin expression, opposing the view that clusterin is involved in apoptotic processes. On the other hand, a new clusterin mRNA isoform was detected and isolated, whose expression was restricted to freshly isolated thymocytes. This

关键词： clusterin sgp-2 thymocytes apoptosis mRNA isoforms.

Structural and mass transport properties of liquid ytterbium in the temperature range 1123 k–1473 k

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Chinese Physics B 2023年第6期32卷 481-488页

作者： D D Satikunvar N k Bhatt B y Thakore Department of Physics Sardar Patel UniversityVallabh VidyanagarGujarat 388120India Department of Physics Maharaja Krishnakumarsinhji Bhavnagar UniversityBhavnagarGujarat 364001India

We have studied the structural and atomic transport properties of liquid f-shell yb in the temperature range 1123 k–1473 k. Pair interactions between atoms are derived using a local pseudopotential. The potential parameters are fitted to the phonon dispersion curve at room temperature. The local pseudopotential used in the present study is computationally more efficient with only three parameters, and it is found to be transferable to the liquid phase without changing the *** the various computed properties agree with reported theoretical and experimental findings, the adopted fitting scheme is justified. As a significant outcome of the study, we find that(i) the melting in yb is governed by the Lindemann's law,(ii)the mass transport mechanism obeys the Arrhenius law,(iii) the role of the three-particle correlation function in deriving the velocity autocorrelation function is small,(iv) the mean-square atomic displacement is more sensitive to the choice of interaction potential than the other bulk properties, and(v) liquid yb does not show liquid–liquid phase transition within the studied temperature range. Further, due to the good description of the structural and mass transport properties, we propose that yb remains divalent at reduced density.

关键词： transport properties pseudopotential single-particle dynamics ytterbium

Coal Gasification in Moving Bed Reactor with a Draft Tube

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Chinese Journal of Chemical Engineering 1999年第2期7卷 178-181页

作者：刘跃进 y.Uemura k.Ijichi y.Hatate DepartmentofChemicalEngineering XiangtanUniversityXiangtan411105China DepsrtmentofAppliedChemistryandChemicalEngineering KagoshiznaUniversityKagoshima390Japan

The application of a new type of moving bed reactor with draft tube for coal gasification was investigated. Successful coal gasification experiments were achieved using the coal gasifier. Product gas containing hydrogen as high as 60% was obtained, and the calorific value of the product of 10 MJ·m-3 was obtained using air as oxidant. The reaction temperature of coal gasification in the moving bed was maintained at 870 °C which was comparatively low for coal gasification. Maximum coal gasification efficiency of 92% was obtained.

关键词： coal gasification moving bed reactor draft tube