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动态mR成像骨盆测量的可重复性:一项多机构的研究

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国际医学放射学杂志 2009年第1期32卷 64-64页

作者： m.e. lockhart J.R. Fielding H.e. Richter L. Brubaker C.G. Salomon 王高峰 Department of Radiology University of Alabama at BirminghamBirminghamAL35249USA

目的为了评估动态mRI用于骨与软组织骨盆测量的可重复性，进行多中心初产妇研究。材料和方法本研究经机构审查委员会批准并遵从HIPPA的规定，所有受试者知情并同意。在6个临床机构中，对3组产后6～12个月的初产妇完成了1．5T标准化... 详细信息

目的为了评估动态mRI用于骨与软组织骨盆测量的可重复性，进行多中心初产妇研究。材料和方法本研究经机构审查委员会批准并遵从HIPPA的规定，所有受试者知情并同意。在6个临床机构中，对3组产后6～12个月的初产妇完成了1．5T标准化的动态骨盆多平面T测mRI扫描：第1组，经阴道分娩伴有肛门括约肌撕裂（93例）；

关键词：骨盆测量可重复性 mR成像动态mRI mRI扫描经阴道分娩肛门括约初产妇

eNHANCemeNT OF ReSISTANCe TO OXIDATIVe DeGRADATION OF NATURAL RUBBeR THROUGH LATeX DeGRADATION

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Chinese Journal of Polymer Science 1998年第2期16卷 170-175页

作者： NWANORH K.O. eNYIeGBULAm m.e. School of Physical Sciences ABIA State University P.M.B. 2000 Uturu NigeriaDepartment of Polymer & Textile Engineering Federal University of Technology P.M.B. 1526 Owerri Nigeria

A fully characterised natural rubber latex was subjected to mechanical degradation by stirring at intervals. The resistance to oxidative degradation of the different samples were studied by measuring the Plasticity retention indices (PRI). The results show that there is an enhancement of the PRI from 57% for the undegraded rubber to 79% for the one-hour degraded sample. Further degradation resulted in decrease of PRI as time of degradation increased. Therefore, the one-hour degraded sample is a special rubber with high oxidation resistance which is of great importance in engineering. (Author abstract) 9 Refs.

关键词： Plasticity Rubber Degradation Oxidation Resistance

A CONJUGATe GRADIeNT meTHOD FOR DISCReTe-TIme OUTPUT FeeDBACK CONTROL DeSIGN

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Journal of Computational mathematics 2012年第3期30卷 279-297页

作者： e1-Sayed m.e. mostafa Department of mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, the discrete-time static output feedback control design problem is con- sidered. A nonlinear conjugate gradient method is analyzed and studied for solving an unconstrained matrix optimization problem that results from this optimal control prob- lem. In addition, through certain parametrization to the optimization problem an initial stabilizing static output feedback gain matrix is not required to start the conjugate gradi- ent method. Finally, the proposed algorithms are tested numerically through several test problems from the benchmark collection.

关键词： Output feedback control Nonlinear conjugate gradient methods Nonlinearprogramming.

STUDY ON THe PROPeRTIeS OF BLeND OF NATURAL RUBBeR LATeX/meTHYL meTHACRYLATe GRAFTeD RUBBeR LATeX BY GAmmA RADIATION

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Chinese Journal of Polymer Science 2007年第5期25卷 519-523页

作者： N.C. Dafader m.e. Haque F. Akhtar Nuclear and Radiation Chemistry Division Institute of Nuclear Science ＆ Technology Bangladesh Atomic Energy Commission P. O. Box 3787 Dhaka Bangladesh

Natural rubber latex （NRL） and methyl methacrylate （mmA） grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from Co-60 source at room tem.e.ature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy. modulus increases from 6.99 mPa to 9.87 mPa for an increase in proportion of mmA grafted rubber from 40% to 60% in the blend at similar absorbed dose. elongation at break and swelling ratio decrease with increasing absorbed dose as well as the mmA grafted rubber content in the blends. The decreasing trend of permanent set is high up to 5 kGy absorbed dose, and beyond that dose, it becomes almost flat.

关键词： Natural rubber latex mmA grafted rubber latex Blend rubber Irradiation Cross-link.

Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

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Journal of materials Science & Technology 1997年第5期13卷 383-388页

作者： Soliman, H.m. Ohamed, K.e. Abd el-Azim, m.e. Hammad, F.H. metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by the pack aluminizing technique using halideactivated pure-Al and Fe-Al packs. The effect of mixture composition, aluminizing tem.e.atureand time and C content of the steel substrate on the structure and thickness of the aluminidelayer, and on the oxidation resistance was investigated. The optimum oxidation resistance canbe achieved with a low carbon steel substrate when the intermetallic phases Fe3Al and FeAlform the surface of the aluminide layer. In this case, the Al concentration at the surface of thealuminide coating is at least ≥15 wt pct. Formation of high Al concentration phases (FeAl3 andFe2Al5) during aluminizing should be avoided as they tend to embrittle the aluminide layer andreduce its oxidation resistance.

关键词： OO Figure Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

THe HADAmARD INeQUALITY FOR CONVeX FUNCTION VIA FRACTIONAL INTeGRALS

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Acta mathematica Scientia 2013年第5期33卷 1293-1299页

作者： m.e.ZDemR S.S.DRAGOmIR C.YILDIZ Department of mathematics K.K.Education Faculty Atatürk University School of engineering & Science Victoria University

In this paper, we establish several inequalities for some differantiable mappings that are connected with the Riemann-Liouville fractional integrals. The analysis used in the proofs is fairly elementary.

关键词： Hadamard's inequality convex functions power-mean inequality Riemann-Liouville fractional integration

The Teodorescu Operator in Clifford Analysis

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Chinese Annals of mathematics,Series B 2012年第4期33卷 625-640页

作者： F.BRACKX H.De SCHePPeR m.e. LUNA-eLIZARRARS m.SHAPIRO Clifford Research Group Faculty of Engineering and Architecture Ghent University Belgium Instituto Politcnico Nacional mexico City Mexico

euclidean Clifford analysis is a higher dimensional function theory centred around monogenic functions, i.e., null solutions to a first order vector valued rotation in- variant differential operator called the Dirac operator. more recently, Hermitian Clifford analysis has emerged as a new branch, offering yet a refinement of the euclidean case; it focuses on the simultaneous null solutions, called Hermitian monogenic functions, to two Hermitian Dirac operators and which are invariant under the action of the unitary group. In euclidean Clifford analysis, the Teodorescu operator is the right inverse of the Dirac operator __0. In this paper, Teodorescu operators for the Hermitian Dirac operators c9~_ and 0_~, are constructed. moreover, the structure of the euclidean and Hermitian Teodor- escu operators is revealed by analyzing the more subtle behaviour of their components. Finally, the obtained inversion relations are still refined for the differential operators is- suing from the euclidean and Hermitian Dirac operators by splitting the Clifford algebra product into its dot and wedge parts. Their relationship with several complex variables theory is discussed.

关键词： Clifford analysis Teodorescu operator Dirac operator

Ocellar lamprophyre dyke bearing mineralization,Wadi Nugrus,eastern Desert,egypt:Geology,mineralogy and geochemical implications

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Chinese Journal Of Geochemistry 2010年第4期29卷 383-392页

作者： Ibrahim m.e. Saleh G.m. Dawood N.A. Aly G.m. Nuclear materials Authority P.O.Box 530El-MaadiCairoEgypt

The ocellar lamprophyre dyke(eNe-WSW) is recorded at Wadi Nugrus,eastern Desert,*** cuts porphyritic biotite granites and varies in thickness from 0.5 to 1.5 m and up to 3 km in *** lamprophyre dyke has been altered,and it is characterized by porphyritic and panidiomorphic textures with plagioclase,olivine,and augite constituting the porphyritic phase in a fine groundmass of the same ***,titanite,apatite,fluorite,graphite,calcite,allanite,autunite and Fe-Ti oxides are accessory ***,chlorite and epidote are secondary *** and hematitization are *** to sub-rounded porphyritic and zoned ocelli with radiate or brush-like shapes are generally common and represent physical traps for *** ocellar features are interpreted to represent the late stage of magmatic segregation or magmatic crystallization involving two immiscible magmatic *** studies of altered lamprophyre samples,based on X-ray diffraction(XRD) and environmental scanning electron microscopy(eSem),indicate the presence of secondary uranium minerals(autunite and uranophane),associated with gold,silver,nickel,atacamite,molybdenum,pyrite and *** presence of kaolinite indicates a high tem.e.ature *** mixing of volatile fluids with meteoric water and fluid-wall rock interaction result in changes of pH and oxygen activity and deposition of base metals in reducing environs(graphite and pyrite).Precipitation of hematite probably decreased the pH of the solution and rose acidic *** sudden change in pH and tem.e.ature of the fluids would lead to destabilization of base metal complexes favoring their *** magma source of the Nugrus lamprophyre is determined to be between calc-alkaline and alkaline and it has HKCAB and shoshonitic nature and may be derived from decomposition melting of such a metasomatised lithospheric *** is a major fractional phase to account for a rapid

关键词：煌斑岩脉矿物学地球化学沙漠埃及地质学黑云母花岗岩矿化

Rock composition and origin of the Duwi Formation calcareous rocks, Upper egypt

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Chinese Journal Of Geochemistry 2005年第4期24卷 316-326页

作者： Baioumy H.m. Attia A.m. Boulis S.N. Hassan m.S. Helmy m.e. Central metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptGeology Dept. Faculty of Science Ain Shams University Abbasia Cairo Egypt

Upper Cretaceous phosphorite beds of the Duwi Formation, Upper egypt, are intercalated with limestone, sandy limestone, marl, calcareous shales, and calcareous sandstone. Calcareous intercalations were subjected to field and detailed petrographic, mineralogical and geochemical investigations in order to constrain their rock composition and origin.; mineralogically, dolomite, calcite, quartz, francolite and feldspars are the non-clay minerals. Smectite, kaolinite and illite represent the clay minerals. major and trace elements can be classified as the detrital and carbonate fractions based on their sources. The detrital fraction includes the elements that are derived from detrital sources, mainly clay minerals and quartz, such as Si, Al, Fe, Ti, K, Ba, V, Ni, Co, Cr, Zn, Cu, Zr, and mo. The carbonate fraction includes the elements that are derived from carbonates, maily calcite and dolomite, such as Ca, mg and Sr. ; Dolomite occurs as being dense, uniform, mosaic, very fine-to-fine, non-ferroan, and non-stoichiometrical, suggesting its early diagenetic formation in a near-shore oxidizing shallow marine environment. The close association and positive correlation between dolomite and smectite indicates the role of clay minerals in the formation of dolomite as a source of mgm-rich solutions.; Calcareous rocks were deposited in marine, oxidizing and weakly alkaline conditions, marking a semi-arid climatic period. The calcareous/argillaceous alternations are due to oscillations in clay/carbonate ratio.

关键词：岩石埃及石灰质白云石成岩作用