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排序方式: 共有574条查询结果,搜索用时 9 毫秒
1.
We show that the LF-algebra considered by Akkar and Nacir in [1] is topologically simple. 相似文献
2.
L. Jackowska-Strumillo J. Sokolowski A. Żochowski A. Henrot 《Computational Optimization and Applications》2002,23(2):231-255
The new method is proposed for the numerical solution of a class of shape inverse problems. The size and the location of a small opening in the domain of integration of an elliptic equation is identified on the basis of an observation. The observation includes the finite number of shape functionals. The approximation of the shape functionals by using the so-called topological derivatives is used to perform the learning process of an artificial neural network. The results of computations for 2D examples show, that the method allows to determine an approximation of the global solution to the inverse problem, sufficiently closed to the exact solution. The proposed method can be extended to the problems with an opening of general shape and to the identification problems of small inclusions. However, the mathematical theory of the proposed approach still requires futher research. In particular, the proof of global convergence of the method is an open problem. 相似文献
3.
Let (E, ¦·¦) be a uniformly convex Banach space with the modulus of uniform convexity of power type. Let be the convolution of the distribution of a random series inE with independent one-dimensional components and an arbitrary probability measure onE. Under some assumptions about the components and the smoothness of the norm we show that there exists a constant such that |{·<t}–{·+r<t}|r
q
, whereq depends on the properties of the norm. We specify it in the case ofL
spaces, >1. 相似文献
4.
Smith BM Lappi SE Brewer SH Dembowy S Belyea J Franzen S 《Langmuir : the ACS journal of surfaces and colloids》2004,20(4):1184-1188
The surface of a germanium internal reflectance element (IRE) was modified to bind 6X-histidine (his)-tagged biomolecules. The step-by-step surface modification was monitored via single-pass attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FT-IR). Initially an adlayer of 7-octenyltrimethoxysilane (7-OTMS) was formed on the Ge crystal through the surface hydroxyl groups, which were produced via ozonolysis of the Ge surface. The vinyl moiety of 7-OTMS was oxidized to a carboxylic acid, which was activated by 1,1'-carbonydiimidazole (CDI) to produce a labile imidazole. The labile imidazole that resulted from the CDI coupling was then displaced by the primary amine of nitrilotriacetic acid (NTA). Nickel sulfate was added to the system, and it coordinated with the three carbonyl groups and the nitrogen on NTA, thus leaving the ability of Ni to coordinate with two adjacent histidine residues. Binding of his-tagged biotin to nickel nitrilotriacetic acid (Ni-NTA) was observed by ATR-FT-IR spectroscopy. The surface modification method presented in this paper had minimal nonspecific binding, the Ni-NTA surface was reusable if stored properly, and complete removal of the organic surface was achievable. 相似文献
5.
The anomalous temperature dependence of the elastic constantsc
11 andc
66 and the elastic instability temperatureT
c are obtained in the two-dimensional microscopic model of the alkali cyanides crystals. It has been found, by means of the Michel and Naudts' theory of the translation rotation coupling, that the orientational disorder in the high-temperature phase leads to the critical softening of the shear elastic constantc
66. 相似文献
6.
Three acetate mutants of the yeast species Yarrowia lipolytica were screened using batch cultivation. The strain Y. lipolytica 1.31 was found to be the most suitable for citric acid production from raw glycerol, a by-product of biodiesel production
from rapeseed oil. At the initial concentration of glycerol of 200 g dm−3, the citric acid production of 124.5 g dm−3, yield of 0.62 g g−1, and productivity of 0.88 g dm−3 h−1 were achieved.
Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May
2006. 相似文献
7.
A. Płochocki K. Rykaczewski T. Batsch J. Szerypo J. Żylicz R. Barden O. Klepper E. Roeckl D. Schardt H. Gabelmann P. Hill H. Ravn T. Thorsteinsen I. S. Grant H. Grawe P. Manakos L. D. Skouras 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(1):43-51
For the first time, detailed decay-spectroscopic investigations were performed for the very neutron-deficientN=50 nuclide98Cd. The98Cd activity was produced in spallation reactions between 600 MeV protons and a natural tin target, yielding a98Cd beam intensity of 10 to 60 atoms/s at the collector of the ISOLDE massseparator. By means of-ray and conversion-electron spectroscopy, 19 transitions were found to follow the +/EC decay98Cd98Ag. The transitions at 61 and 107 keV were shown to beM1(+E2) andE2, respectively, and the98Cd half-life was measured as 9.2±0.3 s. TheQ
EC value of98Cd is determined semiempirically and is compared to model predictions together with the measuredQ
EC values of the neighbouring cadmium isotopes100,102Cd and theN=50 isotones92Mo,94Ru, and96Pd, taken from the literature. The newly established decay scheme of98Cd includes 9 excited states of98Ag. Four states at 1691, 1861, 2164, and 2544 keV are directly fed by 0+ 1+ Gamow-Teller beta transitions with a summed strength of 3.5
–0.7
+0.8
. This value corresponds to 25±5% of the strength predicted for the GT transformation of a g9/2 proton (in98Cd) into a g7/2 neutron (in98Ag) by the extreme single-particle shell model. The GT-strength splitting and quenching, observed for98Cd, are compared with the corresponding data for lighter even-even N=50 isotones, and are discussed with reference to the predictions of more sophisticated nuclear models. We find that only in some cases it is possible to explain qualitatively the observed GT strength distribution and its total magnitude without renormalizing the free-neutron value of the axial-vector coupling constant.Dedicated to Prof. P. Armbruster on the occasion of his 60th birthday 相似文献
8.
Szymon Szufa Piotr Piersa ukasz Adrian Justyna Czerwiska Artur Lewandowski Wiktoria Lewandowska Jan Sielski Maria Dziku Marek Wrbel Marcin Jewiarz Adrian Knapczyk 《Molecules (Basel, Switzerland)》2021,26(4)
Miscanthus is resistant to dry, frosty winters in Poland and most European Union countries. Miscanthus gives higher yields compared to native species. Farmers can produce Miscanthus pellets after drying it for their own heating purposes. From the third year, the most efficient plant development begins, resulting in a yield of 25–30 tons of dry matter from an area of 1 hectare. Laboratory scale tests were carried out on the processes of drying, compacting, and torrefaction of this biomass type. The analysis of the drying process was conducted at three temperature levels of the drying agent (60, 100, and 140 °C). Compaction on a hydraulic press was carried out in the pressure range characteristic of a pressure agglomeration (130.8–457.8 MPa) at different moisture contents of the raw material (0.5% and 10%). The main interest in this part was to assess the influence of drying temperature, moisture content, and compaction pressure on the specific densities (DE) and the mechanical durability of the pellets (DU). In the next step, laboratory analyses of the torrefaction process were carried out, initially using the Thermogravimetric Analysis TGA and Differential Scaning Calorimeter DSC techniques (to assess activation energy (EA)), followed by a flow reactor operating at five temperature levels (225, 250, 275, 300, and 525 °C). A SEM analysis of Miscanthus after torrefaction processes at three different temperatures was performed. Both the parameters of biochar (proximate and ultimate analysis) and the quality of the torgas (volatile organic content (VOC)) were analyzed. The results show that both drying temperature and moisture level will affect the quality of the pellets. Analysis of the torrefaction process shows clearly that the optimum process temperature would be around 300–340 °C from a mass loss ratio and economical perspective. 相似文献
9.
10.