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Three-dimensional structured on-chip stacked zone plates for nanoscale X-ray imaging with high efficiency

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Nano Research 2014年第4期7卷 528-535页

作者： Stephan Werner Stefan Rehbein Peter Guttmann Gerd schneider Helmholtz-Zentrum Berlin fur Materialien und Energie GmbH Institute for Soft Matter and Functional Materials Albert-Einstein-Straβe15 12489 Berlin Germany

Fresnel zone plates are the key optical elements for nanoscale focusing of X-ray beams with high spatial resolution. Conventional zone plates manufactured by planar nanotechnology processes are limited by the achievable aspect ratios of their zone structures. Additionally, ultra-high resolution X-ray optics with high efficiency requires three-dimensional （3-D） shaped tilted zones. The combination of high spatial resolution and high diffraction efficiency is a fundamental problem in X-ray optics. Based on electrodynamical simulations, we find that the optimized zone plate profile for volume diffraction is given by zone structures with radially increasing tilt angles and decreasing zone heights. On-chip stacking permits the realization of such advanced 3-D profiles without significant loss of the maximum theoretical efficiency. We developed triple layer on-chip stacked zone plates with an overlay accuracy of sub-2 nm which fulfills the nanofabrication requirements. Efficiency measurements of on-chip stacked zone plates show significantly increased values compared to conventional zone plates.

关键词： X-ray optics Fresnel zone plates X-ray imaging X-ray microscopy volume diffraction

L_p-DICHOTOMY OF LINEAR DIFFERENTIAL EQUATIONS IN AN ARBITRARY BANACH SPACE

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Chinese Annals of Mathematics,Series B 2003年第4期24卷 485-490页

作者： A.KOSSEVA S.KOSTADINOV K.schneider Department of Mathematics Technical University61Sankt Petersburg blvd4000 PlovdivDepartment of Mathematics and InformaticsUniversity of Plovdiv"P.Hilendarski"24Tzar Assenstr.4000 PlovdivBulgaria.WIAS BerlinMohrenstr.3910117 BerlinDeutschland.

The notion of Lp-dichotomy for linear differential equations with possibly unbounded oper-ator is introduced. By help of Banach fixed point theorem sufficient conditions for the existenceof bounded solutions of nonlin... 详细信息

关键词： Ordinary differential equations Dichotomy Existence of bounded solutions

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Morphological stability of three-dimensional cementite rods in polycrystalline system:A phase-field analysis

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Journal of Materials Science & Technology 2021年第18期77卷 252-268页

作者： Tobias Mittnacht P.G.Kubendran Amos Daniel schneider Britta Nestler Institute of Applied Materials(IAM-CMS) Karlsruhe Institute of Technology(KIT)Strasse am Forum 776131 KarlsruheGermany Institute of Digital Materials Science(IDM) Karlsruhe University of Applied SciencesMoltkestr.3076133 KarlsruheGermany Department of Metallurgical and Materials Engineering National Institute of TechnologyTiruchirappalli-620015Tamil NaduIndia

Transformations accompanying shape-instability govern the morphological configuration and distribution of the phases in a *** to the influence of the microstructure on the properties of a material,in the present work,the stability of three-dimensional rods in a‘representative'polycrystalline system is extensively analysed.A multiphase-field model,which recovers the physical laws and sharpinterface relations,and includes grain boundary diffusion,is adopted to investigate the morphological evolution of the ***,the efficiency of the numerical approach is ensured by establishing the volume-preserving chemical equilibrium through the incorporation TCFe8(CALPHAD)data and solving phase-field evolution in the Allen-Cahn *** morphological evolution of the rod in the representative multiphase system exhibits a unique transformation mechanism which is significantly different from the evolution of an isolated *** is realised that,in a polycrystalline arrangement,irrespective of the initial size of the rod,the shape-change begins with the energy-minimising events at the triple *** early transformation renders a characteristic morphology at the longitudinal ends of the structure,which introduces sufficient driving-force through the curvature-difference for the subsequent morphological *** continued mass transfer to the terminations,ultimately,breaks-off the rod into separate entities that are entangled in the grain *** increase in the aspect ratio of the rod,it is identified that the source of mass transfer,which turns into the ovulation site,shifts from the *** increases the number of fragmentation events and introduces satellite *** size of the satellite particle is dictated by a definite ovulation criterion,which is ascertained by examining the transformation of different-sized rods.A comprehensive understanding of the transformation kinetics and mechanism governing the mo

关键词： Shape instability Pearlite spheroidization Sub-critical annealing Phase-field simulations

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Origin and fate of the nucleolar channel system of normal human endometrium

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Cell Research 1992年第2期2卷 97-102页

作者： J schneider Department of Gynecology and Obstetrics Medical College of Jinan University Guangzhou China Frauenklinik der Medizinischen Hochschule Hannover Germany

Human normal endometrium was examined in *** channel system(NCS)appeared in theendometrial epithelial cells during the early and mid secre-tory phase of menstrual *** NCS was a hollow balllike structure of different sizes and was composed of 2 to 5rows of tubules embedded in an amorphous *** itssurface there were numerous electron dense particles resem-bling *** was usually located within or associatedwith the ***,it was close to the nuclearenvelope or protruding out from the *** occasion,NCS with simplified structure was found in the *** concerning the genesis,involution andfunction(s) of the NCS were discussed.

关键词： nucleolar channel system human endometrial epithelium secretory phase.

Investigation of the phase space in lead‐free(K_(x)Na_(1-x))_(1-y)Li_(y)(Nb_(1-z)Ta_(z))O_(3) ferroelectric ceramics

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Journal of Advanced Ceramics 2015年第4期4卷 282-291页

作者： Henry E.MGBEMERE Rolf JANSSEN Gerold A.schneider Department of Metallurgical&Materials Engineering University of LagosAkokaLagosNigeria Institute of Advanced Ceramics Hamburg University of TechnologyDenickestrasse 1521073 HamburgGermany

A library of ceramic compounds based on the lead-free(K_(x)Na_(1-x))1-yLiy(Nb1-zTaz)O_(3)solid solution has been synthesized and characterized using high-throughput experimentation(HTE)*** phase space previously reported by Saito and Takao has been expanded to{{x,0.1,1.0},{y,0,0.1},{z,0,0.2}},and new phase boundaries are *** relative density values show that with the appropriate sintering temperature,~92%of the theoretical density can be *** relative permittivity values show that with increasing amount of K+and Ta5+,the dielectric constant values *** effect of density on the dielectric constant values is however *** values ranging from 109 to 1013Ω·cm are obtained for the *** piezoelectric charge coefficient values for selected compositions show that higher values are obtained close to the phase boundaries rather than away from *** properties for the ceramic library using the HTE method are generally 15%-20%less than from the conventional *** method is therefore more suited for screening of sample compositions than for producing samples with high piezoelectric properties.

关键词： ferroelectrics high-throughput synthesis (K_(x)Na_(1-x))NbO_(3)(KNN) lead-free ceramics

Quantum mechanic study on cyclic molecul formation from ethynyl radical （C2H） and ethyne （C2H2）

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Journal of Chemistry and Chemical Engineering 2009年第1期3卷 55-60页

作者： INDARTO antonius International R＆D Academy Seoul KIST PO BOX 131 Cheongryang South Korea

The first cyclic molecule formation reactions from ethyne （C2H2）, initiated by ethynyl radical （C2H）, were studied by theoretical quantum mechanic. The study included the competition reaction between structure re-arrangement for the favourable ring-closure mechanism and ethyne addition in each step. The analysis was done by evaluating the energy difference of activation （AE）, entalphy （AH）, Gibbs （AG） of the optimized stable and transition molecules. The reaction temperatures were set at normal （T = 298 K） and combustion （T = 1200 K） condition.

关键词： ethynyl radical ethyne quantum mechanic

Phylogenetic biogeography and taxonomy of disjunctly distributed bryophytes

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Journal of Systematics and Evolution 2009年第5期47卷 497-508页

作者： Jochen HEINRICHS Jrn HENTSCHEL Kathrin FELDBERG Andrea BOMBOSCH Harald schneider Department of Systematic Botany Albrecht von Haller Institute of Plant SciencesGeorg-August-University Botany Department Natural History Museum

More than 200 research papers on the molecular phylogeny and phylogenetic biogeography of bryophytes have been published since the beginning of this *** papers corroborated assumptions of a complex genetic structure of morphologically circumscribed bryophytes,and raised reservations against many morphologically justified species concepts,especially within the ***,many molecular studies allowed for corrections and modifications of morphological classification *** studies reported that the phylogenetic structure of disjunctly distributed bryophyte species reflects their geographical ranges rather than morphological *** data led to new appraisals of distribution ranges and allowed for the reconstruction of refugia and migration *** ranges of bryophytes are often caused by dispersal rather than geographical *** distribution patterns of disjunct bryophytes are likely formed by processes such as short distance dispersal,rare long distance dispersal events,extinction,recolonization and diversification.

关键词： bryophytes cryptic speciation disjunctions divergence time estimates Diversity Arrays Technology DNA sequence variation isozymes molecular phylogeny.

Maintaining nano-lamellar microstructure in friction stir welding (FSW) of accumulative roll bonded (ARB) Cu-Nb nano-lamellar composites (NLC)

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Journal of Materials Science & Technology 2018年第1期34卷 92-101页

作者： Judy schneider Josef Cobb John S.Carpenter Nathan A.Mara Department of Mechanical & Aerospace Engineering University of Alabama in Huntsville Department of Mechanical Engineering Mississippi State University Materials Science and Technologies Division Los Alamos National Laboratory Center for Integrated Nanotechnologies and the Institute for Materials ScienceLos Alamos National Laboratory

Accumulative roll bonded （ARB） Copper Niobium （Cu-Nb） nano-lamellar composite （NLC） panels were friction stir welded （FSWed） to evaluate the ability to join panels while retaining the nano-lamellar structure. During a single pass of the friction stir welding （FSW） process, the nano-lamellar structure of the parent material （PM） was retained but was observed to fragment into equiaxed grains during the second pass. FSW has been modeled as a severe deformation process in which the material is subjected to an instantaneous high shear strain rate followed by extreme shear strains. The loss of the nano-lamellar layers was attributed to the increased strain and longer time at temperature resulting from the second pass of the FSW process. Kinematic modeling was used to predict the global average shear strain and shear strain rates experienced by the ARB material during the FSW process. The results of this study indicate that through careful selection of FSW parameters, the nano-lamellar structure and its associated higher strength can be maintained using FSW to join ARB NLC panels.

关键词： Nano-lamellar materials Accumulative roll bonded Cu-Nb FSW Solid state joining

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Magnetoelectric Coupling in Bilayers of Pb（Zr, Ti）O3 Epoxy and Hot Pressed Manganite Perovskite

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Chinese Physics Letters 2006年第2期23卷 463-466页

作者：张宁印晓明王淼 schneider T. Srinivasan G. Department of Physics Nanjing Normal University Nanjing 210097 Department of Physics Oakland University Rochester MI 48309 USA

The synthesis and magnetoclectric （ME） characterization of bilayers of Pb（Zr, Ti）O3 （PZT） and hot pressed manganite perovskite La0.7Sr0.3MnO3 （LSMO） are discussed. Very strong ME interactions are measured for the bilayers. The bilayers exhibit superior ME coupling compared to thick-film composites prepared by tape casting process. Data of the ME voltage coefficient have been obtained as functions of bias magnetic field H, temperature and frequency. The transverse coupling is stronger than the longitudinal interactions and a maximum in the ME voltage coefficient is measured at 225K. The frequency dependence of the ME voltage coefficient reveals a peak at the electromechanical resonance due to radial modes.

关键词： LAMINATE COMPOSITES