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31.
We consider the two-dimensional Hubbard model including electron-phonon interaction. Strong local correlations (U→∞ limit) are taken into account within the mean-field approximation for auxiliary boson fields. Phonon-assisted transitions between intraand interlayer states are introduced as the source of coupling between two-dimensional CuO2 layers. This type of processes effectively leads to the nonlinear (quadratic) interaction of intralayer electrons withc-axis phonons. We construct the Eliashberg equations for the resulting Hamiltonian and evaluate the superconducting transition temperatureT c. Our model calculation demonstrates that a pronounced enhancement ofT c in thed-wave channel is possible. The largest enhancement ofT c tends to take place for small hole concentrations. This means that the coupling toc-axis phonons could compete with two-dimensional correlations responsible for the onset of antiferromagnetic order. It is remarkable that the two-dimensional features in the normal state are hardly affected by this specific interlayer interaction. Therefore,c-axis two-phonon-mediated interlayer coupling can cooperate with interlayer pair tunneling and substantially contribute to an increased pairing. 相似文献
32.
Wojciech Zalewski Beata Niezgoda-
elasko Marek Litwin 《International Journal of Refrigeration》2000,23(7):553
In the paper the optimization of geometrical and operating parameters for evaporative fluid coolers has been presented. The algorithm of optimizational calculations contains:
- • the mathematical model of heat and mass transfer in evaporative fluid coolers;
- • model of operating costs based, among others, on the Zalewski–Gryglaszewski relations developed by the authors for evaluation of air pressure drops in the heat exchanger;
- • model of evaporative heat exchangers production costs.
33.
Beata Kucieńska Graciela B. Raga Victor Manuel Torres-Puente 《International journal of remote sensing》2013,34(9):2831-2850
Tropical Rainfall Measuring Mission (TRMM) satellite products for the period 1998–2009 are used to elaborate the climatology of vertical hydrometeor profiles and diurnal evolution of rainfall over the Pacific coast of southern Mexico. Precipitation characteristics are compared with those of lightning strokes, registered by the World Wide Lightning Location Network (WWLLN). The WWLLN data are verified against a climatological product (High-Resolution Monthly Climatology, HRMC) obtained from merged data sets of the TRMM Lightning Imaging Sensor (LIS) and the Optical Transient Detector (OTD) of the MicroLab-1 satellite. The TRMM 2A12 data set reveals that summer precipitation over the study region is a result of mixed phase processes, whereas during winter and spring, there is a significant contribution of warm precipitation over land. Diurnal evolution of rainfall retrieved from the 3B42 TRMM product and lightning registered by the WWLLN follows the sea–land breeze cycle measured by Baumgardner et al. (2006; Evolution of anthropogenic aerosols in the coastal town of Salina Cruz, Mexico: part I particle dynamics and land–sea interactions, Science of the Total Environment, 367, pp. 288–301). The spatial distribution of lightning is similar to that of rainfall; however, over the seaside coastal region, a phase shift is observed between these two variables, with the maximum lightning activity occurring about 3 hours before the precipitation peak. Monthly distribution of flashes is monomodal over land and bimodal over the ocean. Over the ocean, the evolution of monthly rainfall during summer is contrary to that of lightning activity: the months with highest precipitation (June and September) correspond to those with the lowest number of lightning strokes, whereas during the mid-summer drought, an increase in electrical activity is observed. An explanation for this phenomenon, related to the wind circulation and its effect on the concentration of aerosol particles, is proposed. 相似文献
34.
This paper describes key aspects of remote service invocation in federations of OSGi containers. It refers to the OSGi Remote Service Admin specification and describes its efficient implementation over message‐oriented middleware. Scalability problems of several different approaches to implementation are identified, and a solution in a form of innovative Remote Service Admin model extension is proposed. The extension, named On‐demand Remote Service Admin, is analyzed and validated in the context of a motivating scenario. Validation includes performance and scalability evaluation, which confirms that all assumed requirements have been satisfied by the constructed prototype. Finally, the presented research is compared with related works. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
35.
Lara Valentín Beata Kluczek‐Turpeinen Pekka Oivanen Annele Hatakka Kari Steffen Marja Tuomela 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):851-858
BACKGROUND: For most dioxin‐contaminated sawmill soils, combustion is recommended. However, the process may be inefficient if the soil has a high organic matter content. The use of saprotrophic basidiomycetous fungi is an alternative for pretreatment of this kind of soil. A total of 147 fungi were evaluated for their ability to grow in sawmill soil. From this screening, the best soil colonizing fungi were selected to study their enzyme activities and degradation of soil organic matter. Pine (Pinus sylvestris) bark was used as a co‐substrate to propagate the fungi into the soil. The activities of manganese peroxidase (MnP), laccase, endo‐1,4‐β‐glucanase, endo‐1,4‐β‐xylanase, and endo‐1,4‐β‐mannanase were analysed from the inocula and fungal treated soil. RESULTS: The screening revealed that 56 out of 147 fungi were able to grow in non‐sterile soil, and most of them were litter‐decomposing fungi (LDF). In pine bark cultures, the highest enzyme activities were observed with Phanerochaete velutina, which produced 5 U g?1 of MnP. The activity of endo‐1,4‐β‐glucanase was generally higher than that of other hydrolytic enzymes. The highest carbon loss from soil with a high organic matter content was achieved by P. velutina (3.4%) and Stropharia rugosoannulata (2.4%). CONCLUSIONS: Many LDF, and in addition the white‐rot fungus P. velutina, are potential degraders of soil organic matter since they showed good growth and respiratory activity. Pine bark was a suitable lignocellulosic co‐substrate and a good promoter of MnP activity. Copyright © 2009 Society of Chemical Industry 相似文献
36.
The effects of alumina, silica and carbon on hydrogen adsorption on nickel were studied by the temperature-programmed desorption (TPD) method. The examinations were carried out in the flow system, starting TP measurement at 100 K, which resulted in the formation of complete characteristics of the interaction of hydrogen with supported nickel. The examinations have shown that each support modifies in its own way the state of hydrogen adsorbed on nickel. Alumina and silica insignificantly affect hydrogen strongly adsorbed on nickel, but significantly affect hydrogen weakly adsorbed; in particular, the effect of silica depends qualitatively on the way of preparation of the examined sample. Carbon affects significantly both strongly and weakly adsorbed hydrogen. 相似文献
37.
Beata Olejnik Anna Jarz?b Ewa M. Kratz Mariusz Zimmer Andrzej Gamian Miros?awa Ferens-Sieczkowska 《International journal of molecular sciences》2015,16(7):14933-14950
The impact of seminal plasma components on the fertilization outcomes in humans is still under question. The increasing number of couples facing problems with conception raises the need for predictive biomarkers. Detailed understanding of the molecular mechanisms accompanying fertilization remains another challenge. Carbohydrate–protein recognition may be of key importance in this complex field. In this study, we analyzed the unique glycosylation pattern of seminal plasma proteins, the display of high-mannose and hybrid-type oligosaccharides, by means of their reactivity with mannose-specific Galanthus nivalis lectin. Normozoospermic infertile subjects presented decreased amounts of lectin-reactive glycoepitopes compared to fertile donors and infertile patients with abnormal semen parameters. Glycoproteins containing unveiled mannose were isolated in affinity chromatography, and 17 glycoproteins were identified in liquid chromatography-tandem mass spectrometry with electrospray ionization. The N-glycome of the isolated glycoproteins was examined in matrix-assisted laser desorption ionization mass spectrometry. Eleven out of 27 identified oligosaccharides expressed terminal mannose residues, responsible for lectin binding. We suggest that lowered content of high-mannose and hybrid type glycans in normozoospermic infertile patients may be associated with impaired sperm protection from preterm capacitation and should be considered in the search for new infertility markers. 相似文献
38.
39.
Janina Kabatc Edyta Krzyżanowska Beata Jędrzejewska Marek Pietrzak Jerzy Pączkowski 《应用聚合物科学杂志》2010,118(1):165-172
Results of kinetic studies of two‐component photoinitiator systems used in the visible‐light photoinduced polymerization of 2‐ethyl‐2‐(hydroxymethyl)‐1,3‐propanediol triacrylate are presented. Nine different styrylquinolinum dyes coupled with n‐butyltriphenylborate as a coinitiator have been used as photoinitiating systems. Reactive radicals that initiate the polymerization are formed by the well‐known mechanism of photoinduced electron transfer between dye cations acting as electron acceptors and borate anions acting as electron donors. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
40.
Plants infested with herbivores release specific volatile compounds that are known to recruit natural enemies. The response
of natural enemies to these volatiles may be either learned or genetically determined. We asked whether there is genetic variation
in the response of the predatory mite Phytoseiulus persimilis to methyl salicylate (MeSa). MeSa is a volatile compound consistently produced by plants being attacked by the two-spotted
spider mite, the prey of P. persimilis. We predicted that predators express genetically determined responses during long-distance migration where previously learned
associations may have less value. Additionally, we asked whether these responses depend on odors from uninfested plants as
a background to MeSa. To infer a genetic basis, we analyzed the variation in response to MeSa among iso-female lines of P. persimilis by using choice-tests that involved either (1) MeSa presented as a single compound or (2) MeSa with background-odor from
uninfested lima bean plants. These tests were conducted for starved and satiated predators, i.e., two physiological states,
one that approximates migration and another that mimics local patch exploration. We found variation among iso-female lines
in the responses to MeSa, thus showing genetic variation for this behavior. The variation was more pronounced in the starved
predators, thus indicating that P. persimilis relies on innate preferences when migrating. Background volatiles of uninfested plants changed the predators’ responses to
MeSa in a manner that depended on physiological state and iso-female line. Thus, it is possible to select for context-dependent
behavioral responses of natural enemies to plant volatiles. 相似文献