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41.
Rafal M. Molak Krystian Paradowski Tomasz Brynk Lukasz Ciupinski Zbigniew Pakiela Krzysztof J. Kurzydlowski 《International Journal of Pressure Vessels and Piping》2009,86(1):43-47
The aim of this study was to measure the mechanical properties of weld material taken from a single weld bead laid down on a 316L steel plate. Due to the low available volume of weld material, microsamples with a total length of 5.5 mm were used. The Digital Image Correlation method (DIC), which enables measurement of mechanical properties of very small samples, was employed for the strain measurements in a uniaxial tensile test. Samples were cut out from three different zones of the specimen: plate, weld, and the heat affected zone. The material from heat affected zone showed the highest value of the Ultimate Tensile Strength (UTS) (580 ± 7 MPa) and yield strength (339 ± 6 MPa). Plate material had lower UTS (559 ± 5 MPa) and yield strength (304 ± 7 MPa). The lowest values of UTS (526 ± 6 MPa) and yield strength (291 ± 8 MPa) have been revealed for the weld. The values obtained for UTS, yield strength and elongation to failure for the plate material were compared with data obtained using standard test specimens. No significant differences between results obtained for the microsamples and standard samples have been found. 相似文献
42.
Zbigniew Hnatejko 《中国稀土学报(英文版)》2012,(6):552-558
New solid complexes of europium,uranyl and zinc ions with N-oxides of 4-chloro-2,6-dimethylpyridine,quinoline and 4-meth-oxyquinaldinic acid in presence different anions were obtained and characterized by elemental and TG analyses,IR and luminescence spectra. The compounds are crystalline,hydrated or anhydrous salts with colours typical of metal ions.Thermal studies showed that in hydrated salts lattice or coordination water molecules are present.A role of different anions in the formation of various types of the complexes is presented. 相似文献
43.
This article presents a method of filtering thermal images by means of approximation using cubic B-spline patch surfaces. Approximation uses chord length parameterization with non-uniform distribution of knots, depending on the change rate of pixel values in rows and columns of the image. Advantages of approximation with such parameterization are compared with popular uniform parameterization. Presented method is very versatile and can be used for example in 3D surface topography of objects tested with stereoscopic microscopes, in resolution change of arbitrary images or modeling processes depending on two parameters. Filtering results are presented using plugin for the Soft4Image program, which was designed to unify different digital signal processing algorithms. 相似文献
44.
Sometime Query Answering Systems (QAS) for a Distributed Autonomous Information System (DAIS) may fail by returning the empty set of objects as an answer for a query q. Systems in DAIS can be incomplete, have hierarchical attributes, and the semantics of attributes and their values may differ between sites.
Also, if there are no objects in S matching q, the query may fail when submitted to S. Alternatively, QAS for S may try to relax the query q as it was proposed in T. Gaasterland (IEEE Expert, 12(5), 1997, 48–59), P. Godfrey (International Journal of Cooperative Information Systems, 6(2), 1997, 95–149) and W. Chu et al. (Journal of Intelligent Information Systems, 6(2/3), 1996, 223–259). It means that q can be replaced by a new more general query. Clearly, the goal is to find possibly the smallest generalization of q which will not fail in S. Smaller generalizations guarantee higher confidence in objects returned by QAS. Such QAS is called cooperative (only one site is involved). Queries may also fail in S when some of the attributes listed in q are outside the domain of S. To resolve this type of queries, assuming that S is a part of DAIS, we may extract definitions of such attributes from information systems residing at some of the remote sites for S and next use them to approximate q in S. In order to do that successfully, we assume that all involved systems have to agree on the ontology of some of their common
attributes Z.W. Raś and A. Dardzińska (Information Systems International Journal, 29(1), 2004, 47–58; Proceedings of FQAS 2004 Conference, LNCS/LNAI No. 3055, 2004, pp. 125–136); Z.W. Raś and S. Joshi, Fundamenta Informaticae Journal, 30(3/4), 1997, 313–324. QAS based on the above strategy is called collaborative (minimum two sites are involved). Similarly, a query may fail in S when the granularity of an attribute used in q is finer than the granularity of the same attribute in S. This paper shows how to use collaboration and cooperation approach to solve failing queries in DAIS assuming that attributes are hierarchical. Some aspects of a collaboration strategy dealing with failing query problem for
non-hierarchical attributes have been presented in Z.W. Raś and A. Dardzińska (Information Systems International Journal, 29(1), 2004, 47–58; Proceedings of FQAS 2004 Conference, LNCS/LNAI No. 3055, 2004, pp. 125–136). 相似文献
45.
Absorption and photoreflectance spectroscopy of zinc phthalocyanine (ZnPc) thin films grown by thermal evaporation 总被引:1,自引:0,他引:1
Optical properties of the as-deposited and annealed ZnPc layers have been investigated using absorption, reflectance and modulated photoreflectance methods. The absorption coefficient of ZnPc layers was directly determined from the transmission and reflection spectra. The absorption spectra were analyzed in terms of the mixed Lorentz–Lorenz model. We found that annealing thin layers at 580 K caused a structural transformation, which results in the decrease of the absorption coefficient and the shifting of all peak position to lower energies except for the peak of the N-band. Photoreflectance spectroscopy confirmed that there exist three transitions in the Q-band region of the studied material. Complex refractive index and dielectric constants of the ZnPc layer were directly found from the spectral data. 相似文献
46.
A laboratory scale submerged filter filled with crushed marble was used for the nitrification process investigation. The results obtained showed that the alkaline reactor filling material react with the hydrogen ions released during the process course which enables reactor exploitation without any pH value or alkalinity control. 相似文献
47.
Zbigniew K. Walczak 《应用聚合物科学杂志》1973,17(1):169-176
The flow pattern of molten polymer through capillaries was studied by using a tracing method. An incompatible polymer was added to polypropylene as a tracer, and the influence of shear in a capillary rheometer on the tracer particle size as well as on the distribution of the particles in the extrudate in relation to flow was studied. It was found that the particle size varied inversely with shear rate of extrusion, capillary aspect ratio, polymer viscosity, and extrusion temperature. The flow was found to be of the telescopic type, and the tracer particle size was independent of position along the radius of the cylindrical extrudate. It is assumed that the supermolecular structure of a polymer melt is of the cluster type suggested by Busse, and it is postulated that spherical clusters of molecules in the melt are modified by shear analogously to the spherical particles of the incompatible tracer polymer. The large spectrum of melt properties obtainable, by various shearing treatments, from a polymer of constant molecular structure suggests that a wide range of supermolecular structures must be possible in the polymer melt. 相似文献
48.
49.
EPR studies using naturally abundant and 95Mo-enriched molybdenum have shown that reduced MoO
x
/SiO2catalysts with different dispersion of molybdenum provide a unique opportunity for molecular-level investigations of surface phenomena involved in the bonding to and activation of small molecules by oxide surfaces. Different types of electron transfer (ET) processes accompanying the activation of O2and N2O as well as the reactivity of O-and CH2OH transients with coadsorbed CH3OH and O2, respectively, have been identified. They include nondissociative and dissociative ET, surface intramolecular ET, and electroprotic transformation (ET coupled with proton transfer). In the case of methanol dehydrogenation it was found that if the reaction occurs on the MoO
x
cluster centers, ET exhibits a complementary character, in contrast to isolated Mo centers where noncomplementary ET accompanied by migration of the hydroxymethyl intermediate is observed. 相似文献
50.
Model-Supported Impact Assessment for the Water Sector in Central Germany Under Climate Change—A Case Study 总被引:1,自引:0,他引:1
Fred Fokko Hattermann Mathias Weiland Shaochun Huang Valentina Krysanova Zbigniew W. Kundzewicz 《Water Resources Management》2011,25(13):3113-3134
Climate change challenges water managers and researchers to find sustainable management solutions, in order to avoid undesirable
impacts on water resources, environment and water-dependent sectors. Needed are projections into the future for the main driving
forces, the resulting pressures on water resources, and quantification of the impacts. Modeling studies can play an important
role in investigating, quantifying, and communicating possible impacts of climate change, with account of uncertainty of the
results. However, climate change related impacts and a need for adaptation still play a minor role in current river basin
management plans that have to comply e.g. with the EU Water Framework Directive (WFD). One important reason is that climate
impact assessment is generally done in research institutes, while management plans are designed by practitioners working in
national and regional environmental agencies and water supply companies. Knowledge transfer from science to practice and visa
versa is often missing. In the present study, we propose a methodology and a case study for model-supported decision making
in the water sector applicable to a participatory water resources planning process. The methodology is applied in a case study
investigating climate change impacts on water resources. The case study area is the German State of Saxony-Anhalt, where the
task was to develop a climate change impact assessment including possible adaptation measures as basis for a federal adaptation
directive. 相似文献