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排序方式: 共有459条查询结果,搜索用时 15 毫秒
71.
Winicjusz Drozdowski Andrzej J. Wojtowicz Dariusz Wi
niewski Piotr Szupryczy
ski Sebastian Janus Jean-Luc Lefaucheur Zhenhui Gou 《Journal of Alloys and Compounds》2004,380(1-2):146-150
Radioluminescence and UV-excited photoluminescence spectra, photoluminescence time profiles, thermoluminescence glow curves and gamma-excited energy spectra (determining scintillation light yields) of several Lu2SiO5:Ce and Y2SiO5:Ce samples were recorded. The results are analyzed with attention focused on possible correlations between trap distributions, VUV responses, and light yields. The aspect of two distinct sites occupied by Ce3+ ions is also discussed. 相似文献
72.
In the paper, we prove the bang-bang principle for a continuous linear nonautonomous Roesser system and some approximation
result (with respect to piecewise constant controls) for a continuous nonautonomous Roesser system which is linear in the
state and nonlinear in the control.
Published online: April 2006
The preparation of this paper was supported by the State Committee for Scientific Research, Poland, under Grant 7 T11A 004
21 相似文献
73.
Ludomir
lusarski Dariusz Bieliski Andrzej Wochowicz Czesaw
lusarczyk 《Polymer International》1995,36(3):261-268
Blends of ethylene–propylene–diene rubber (EPDM) and low density polyethylene (PEid) or isotactic polypropylene (iPP) crosslinked by dicumyl peroxide (DCP) have been prepared. Their morphology, reactivity of the components and crystallinity have been studied. The blends are microheterogeneous. Both plastomers, but particularly iPP, decrease the crosslinking efficiency of EPDM by DCP. It was found that they also influence the mechanical properties of the blends. The effect of iPP is far more pronounced than that of PEId, because of an increase in crystalline phase content. iPP particles play a role as nuclei for propylene monomer units in EPDM, whereas PEId particles are solvated by the elastomer matrix. 相似文献
74.
Dariusz Gatarek 《Systems & Control Letters》1982,2(4):248-254
In the paper a problem of renewal of a nonhomogeneous Markov chain with incomplete information given by a point process is treated. A long run average cost is studied. The article applies the ‘crossing level’ method given by Davis. An example of exponentially distributed time-to-failure is given. 相似文献
75.
Effects of a nonuniform vertical profile of chlorophyll concentration on remote-sensing reflectance of the ocean 总被引:2,自引:0,他引:2
Numerical simulations of radiative transfer were used to examine the effects of a nonuniform vertical profile of the inherent optical properties of the water column associated with the vertical profile of chlorophyll concentration, Chl(z), on the spectral remote-sensing reflectance, Rrs(gamma), of the ocean. Using the Gaussian function that describes the Chl(z) profile, we simulated a relatively broad range of open-ocean conditions characterized by the presence of a subsurface Chl maximum at depths greater than or equal to 20 m. The simulations for a vertically nonuniform Chl(z) were compared with reference simulations for a homogeneous ocean whose Chl was identical to the surface Chl of inhomogeneous cases. The range of values for the Gaussian parameters that produce significant differences in Rrs(gamma) (> 5%) was determined. For some vertical structures of Chl(z) considered, the magnitude of Rrs(gamma) and the blue-to-green band ratios of Rrs(gamma) differ significantly from the reference values of homogeneous ocean (> 70% in extreme cases of low surface chlorophyll of 0.02 mg m(-3) and shallow pigment maximum at 20 m). The differences are small or negligible when the nonuniform profiles are characterized by a surface Chl greater than 0.4 mg m(-3) or a depth of Chl maximum greater than 45 m (65 m in extremely clear waters with a surface Chl of 0.02 mg m(-3) or less). The comparison of modeling results with the current algorithm for retrieving the global distribution of chlorophyll from satellite imagery of ocean color suggests that strong effects of the subsurface chlorophyll maximum on reflectance at low surface chlorophyll concentrations can lead to a severalfold overestimation in the algorithm-derived surface chlorophyll. Examples of field data from the Sea of Japan and the north polar Atlantic Ocean are used to illustrate various nonuniform pigment profiles and their effect on the blue-to-green ratio of Rrs(gamma). 相似文献
76.
Dariusz Dziki 《Journal of food engineering》2011,104(4):585-591
This article presents the results of investigations on the pulverizing grinding energy requirements for whole and preliminary ground wheat kernels regarding different moisture levels. Four common wheat cultivars (Triticum aestivum, ssp. vulgare) differing in kernel hardness were used for tests. When the moisture of kernels ranged from 14% to 20% w.b. the lower values of average particle size were obtained for preliminary ground wheat. The pulverizing energy requirements expressed by different grinding indices were considerably lower for preliminary ground kernels rather than for whole kernels. The values of specific pulverizing energy ranged from 32.6 to 79.0 kJ kg−1 for whole kernels, whereas the values of total specific grinding energy (the sum of specific grinding energy and specific pulverizing energy) changed from 23.1 to 44.4 kJ kg−1 for the two-stage ground wheat. In addition, the other values of pulverizing indices confirmed that preliminary size reduction significantly reduced the grinding energy requirements. 相似文献
77.
Guangran Zhang Iva Milisavljevic Karina Grzeszkiewicz Piotr Stachowiak Dariusz Hreniak Yiquan Wu 《Journal of the European Ceramic Society》2021,41(6):3621-3628
Highly transparent X2O3 sesquioxide ceramics were obtained from a solid solution of five different oxides (Lu2O3, Y2O3, Yb2O3, Gd2O3, and Dy2O3), mixed in an equal molar ratio according to the principle of high-entropy. The fabricated (Lu, Y, Yb, Gd, Dy)2O3 ceramics achieved 99.97 % of the relative density and exhibited a high degree of optical transparency with the in-line transmittance of almost 80 % in the visible wavelength range. Emissions of Gd3+ (6PJ → 8S7/2 at 312 nm), Dy3+ (4F9/2 → 6H15/2 at 492 nm and 4F9/2 → 6H13/2 at 572 nm), and Yb3+ (2F5/2 → 2F7/2 at 1031 nm) suggested a potential application of the high-entropy ceramics as multi-wavelength emission phosphor transparent ceramics. High-entropy ceramics also exhibited lower specific heat and thermal conductivity compared to single-element sesquioxide ceramics. This work demonstrated that highly transparent oxide ceramics, with complex chemical compositions and good optical properties, could be obtained using the high-entropy principle. 相似文献
78.
Novel Positive Allosteric Modulators of µ Opioid Receptor—Insight from In Silico and In Vivo Studies
Damian Bartuzi Ewa Kdzierska Agnieszka A. Kaczor Helmut Schmidhammer Dariusz Matosiuk 《International journal of molecular sciences》2020,21(22)
Opioids are the drugs of choice in severe pain management. Unfortunately, their use involves serious, potentially lethal side effects. Therefore, efforts in opioid drug design turn toward safer and more effective mechanisms, including allosteric modulation. In this study, molecular dynamics simulations in silico and ‘writhing’ tests in vivo were used to characterize potential allosteric mechanism of two previously reported compounds. The results suggest that investigated compounds bind to μ opioid receptor in an allosteric site, augmenting action of morphine at subeffective doses, and exerting antinociceptive effect alone at higher doses. Detailed analysis of in silico calculations suggests that first of the compounds behaves more like allosteric agonist, while the second compound acts mainly as a positive allosteric modulator. 相似文献
79.
80.
Metallurgical and Materials Transactions A - The reduction of freckle defect in the single-crystal blade root by controlling local cooling conditions was investigated. Application of the IRBs... 相似文献