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排序方式: 共有217条查询结果,搜索用时 9 毫秒
111.
Gernot M. Wallner Zoltan Major Günther A. Maier Reinhold W. Lang 《Polymer Testing》2008,27(3):392-402
The effect of annealing 50 μm thick, extruded poly(vinylidene fluoride) films in form (-PVDF) was investigated by differential scanning calorimetry and mechanical testing on unnotched and double-edge notched tensile specimens. As to the fracture behavior, micromechanisms of cavitation, spherulite breakdown, fiber bundle structure formation and - to β-phase transformation were detected. The progressive structural evolution taking place during annealing affected the deformation and fracture behavior significantly. While the annealing-induced subtle distinctions in microstructure are slightly reflected by the determined mechanical and essential work of fracture (EWF) properties, a distinct differentiation was possible by analysis of the process zone. A correlation between characteristic values of the process zone at necking and the endothermic transitions due to secondary crystallization determined by differential scanning calorimetry (DSC) was established. Annealing of PVDF films facilitates the micromechanism of cavitation, which is presumably related to perfection of morphological superstructures (spherulites) and, thus, interspherulitic stress concentration and failure. 相似文献
112.
In this paper we construct the equilibrium states of Dyson's vector-valued hierarchical model with parameter
at low temperatures and describe their large-scale limit. The analogous problems for
<c<2 and 1<c<
were solved in our papers [1] and [2]. In the present case the large-scale limit is similar to the case
<c<2, i.e. it is a Gaussian self-similar field with long-range dependence in the direction orthogonal to and a field consisting of independent Gaussian random variables in the direction parallel with the magnetization. The main difference between the two cases is that now the normalizing factor in the direction of the magnetization contains, beside the square-root of the volume, a logarithmic term too.Dedicated to Roland Dobrushin 相似文献
113.
S. Deachapunya P. J. Fagan A. G. Major E. Reiger H. Ritsch A. Stefanov H. Ulbricht M. Arndt 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(2):307-313
Slow beams of neutral molecules are of great interest for
a wide range of applications, from cold chemistry through precision
measurements to tests of the foundations of quantum mechanics. We
report on the quantitative observation of thermal beams of
perfluorinated macromolecules with masses up to 6000 amu, reaching
velocities down to 11 m/s. Such slow, heavy and neutral molecular
beams are of importance for a new class of experiments in
matter-wave interferometry and we also discuss the requirements for
further manipulation and cooling schemes with molecules in this
unprecedented mass range. 相似文献
114.
115.
Papp L Palcsu L Major Z Rinyu L Tóth I 《Isotopes in environmental and health studies》2012,48(4):494-511
This paper describes the procedure followed for noble gas measurements for litres, millilitres and microlitres of water samples in our laboratory, including sample preparation, mass spectrometric measurement procedure, and the complete calibrations. The preparation line extracts dissolved gases from water samples of volumes of 0.2?μ l to 3?l and it separates them as noble and other chemically active gases. Our compact system handles the following measurements: (i) determination of tritium concentration of environmental water samples by the (3)He ingrowth method; (ii) noble gas measurements from surface water and groundwater; and (iii) noble gas measurements from fluid inclusions of solid geological archives (e.g. speleothems). As a result, the tritium measurements have a detection limit of 0.012 TU, and the expectation value (between 1 and 20 TU) is within 0.2 % of the real concentrations with a standard deviation of 2.4 %. The reproducibility of noble gas measurements for water samples of 20-40?ml allows us to determine solubility temperatures by an uncertainty better than 0.5?°C. Moreover, noble gas measurements for tiny water amounts (in the microlitre range) show that the results of the performed calibration measurements for most noble gas isotopes occur with a deviation of less than 2 %. Theoretically, these precisions for noble gas concentrations obtained from measurements of waters samples of a few microlitres allow us to determine noble gas temperatures by an uncertainty of less than 1?°C. Here, we present the first noble gas measurements of tiny amounts of artificial water samples prepared under laboratory conditions. 相似文献
116.
M. Arndt M. Berninger S. Deachapunya S. Gerlich L. Hackermüller A. G. Major M. Marksteiner A. Stéfanov H. Ulbricht 《The European physical journal. Special topics》2008,159(1):1-9
We investigate the prospects of near-field
matter-wave interferometry for the sensitive determination
of molecular properties, such as electric polarizabilities,
electric and magnetic dipole moments or even life-times of
some molecular states. We discuss how important principles
of our present quantum experiments can be transferred to
the classical regime, i.e. to a Moiré deflectometer in
order to also measure characteristic properties of large
clusters and biomolecules. 相似文献
117.
文章合成了N,N’-二正丁基四羧酸二酰亚胺,并纯化、调晶,进行了IR、元素分析、X射线等测定。分析该化合物在DMF中的紫外光谱(最大吸收波长524.80 nm)、荧光光谱(最大发射波长539.0 nm)、Stokes位移(数值15 nm)等光谱性质。在400~700 nm范围内,α晶型薄膜紫外-可见吸收出现很强的吸收峰,且由β型变为α型,最大吸收波长有明显的红移(545 nm变为580 nm)。X射线粉末衍射也反映出α晶型的2θ在26.0°处衍射峰CPS为2 508,β型在25.2°为1 891。α,β晶型作为电荷产生材料制得的功能分离型有机光导体,在光源滤波波长λ=532 nm曝光下,测得含α,β感光体达到饱和电位的时间分别为46,93.98 s,光衰电位(5.3千伏电压负充电电晕,1~2 s后的表面电位)分别为727和525 V,半衰曝光量分别为4.32,4.34μJ.cm-2,残余电位分别为30和45 V等光导性能数值。 相似文献
118.
M. Molnár L. Palcsu É. Svingor I. Futó Z. Major L. Rinyu M. Veres 《Czechoslovak Journal of Physics》2006,56(1):D637-D644
The paper presents the results of a long-term measurement series using hermetic containers to make more precise quantitative
estimation of the generation rates and radioactivity of the gas in a drum of low and intermediate level radioactive waste
(L/ILW) packages. Development of special preparation lines and isotope-analytical measurements of the headspace gas samples
were performed in the ATOMKI. Stable isotope measurements were executed from the CO2 and CH4 fractions by stable isotope ratio mass spectrometer. Noble gas (He) measurements were done by noble gas mass spectrometer.
The tritium content of the vapour, H2 and CH4 fractions was measured in H2O chemical form by a low background liquid scintillation counter. The 14C content of the CO2 and CH4 fractions of the headspace gas samples was measured by a low background gas proportional counter system. 相似文献
119.
120.
M. Hampele D. Herlach A. Kratzer G. Majer J. Major H. -P. Raich R. Roth C. A. Scott A. Seeger W. Templ M. Blanz S. F. J. Cox K. Fürderer 《Hyperfine Interactions》1991,65(1-4):1081-1087
Resonant transitions between the Zeeman levels of positive muons implanted into α-iron foils have been observed above the
Curie temperature by applying a 17.8 MHz transverse radio-frequency field and varying the longitudinal external field. Resonance
signals of free and trapped muons are detected. 相似文献