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151.
152.
S. Balestra S. Cecchini G. Giacomelli R. Giacomelli S. Manzoor L. Patrizii V. Popa 《Czechoslovak Journal of Physics》2006,56(1):A221-A230
The strange quark matter (SQM) may be the ground state of QCD; nuggets of SQM could be present in cosmic rays (CR). SLIM is a large area experiment, using CR39 and Makrofol track etch detectors, presently deployed at the high altitude CR Laboratory of Chacaltaya, Bolivia. We discuss the expected properties of SQM, from the point of view of its search with SLIM. We present also some preliminary results from SLIM. 相似文献
153.
Quite recently, by using semi-open (resp.α-open, preopen,β-open) sets in a topological space, the notions ofsg*-closed (resp.αg*-closed,pg*-closedβg*-closed) sets are indroduced and investigated in [8]. These subsets place between closed sets andg-closed sets due to Levine [5]. In this paper, we introduce the notion ofmg*-closed sets and obtain the unified theory for collections of subsets between closed sets andg-closed sets. 相似文献
154.
Stefanie Zuber Katharina Landfester Daniel Crespy Ana‐Maria Popa 《Journal of polymer science. Part A, Polymer chemistry》2013,51(15):3308-3313
Poly(N‐vinylcaprolactam) (PVCL) and poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) are well known for their thermoresponsive behavior in aqueous solutions. Indeed, they display lower critical solution temperatures (LCST) in the physiological range, which makes them interesting for biomedical devices and use in drug delivery systems. Homopolymers of N‐vinylcaprolactam and di(ethylene glycol) methyl ether methacrylate as well as copolymers thereof were synthesized by solution and direct miniemulsion polymerizations. The cloud points of the copolymers in aqueous solution were investigated as a function of temperature, comonomer ratio, and in the presence of model pharmaceutical ingredients. By variation of the comonomer ratio, it was possible to control the cloud point temperature between 26 and 35 °C, which was found to be beneficial to attenuate the effect of the drugs that also altered the cloud points. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3308–3313 相似文献
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Dumitru Popa 《Mathematische Nachrichten》2015,288(8-9):1028-1046
We prove that Cohen p‐summing operators satisfy multiple summability properties. Some of these multiple summability properties are new even in the linear case. For example, we prove that the multilinear functional associated to a Cohen p‐summing n‐linear operator is multiple ‐summing. 相似文献
158.
In this paper the operator-valued martingale transform inequalities in rearrangement invariant function spaces are proved. Some well-known results are generalized and unified. Applications are given to classical operators such as the maximal operator and the p-variation operator of vector-valued martingales, then we can very easily obtain some new vector-valued martingale inequalities in rearrangement invariant function spaces. These inequalities are closely related to both the geometrical properties of the underlying Banach spaces and the Boyd indices of the rearrangement invariant function spaces. Finally we give an equivalent characterization of UMD Banach lattices, and also prove the Fefferman-Stein theorem in the rearrangement invariant function spaces setting. 相似文献
159.
Antoniea Poiata Iuliana Motrescu A. Nastuta D.E. Creanga G. Popa 《Journal of Electrostatics》2010,68(2):128-131
The effect of an atmospheric pressure plasma dielectric barrier discharge on some microorganisms was investigated, due to the possible extent of plasma applications in controlling microbial contamination. The present investigation involved both Gram-positive and Gram-negative germs – bacteria and yeasts – treated in helium plasma (asymmetric dielectric barrier discharge) for various time durations between 25 s and 100 s. Circular growth inhibition zones were measured for two distances between the discharge electrodes, the correlations with the plasma treatment time being analyzed. Differences between the sensitivities of the four tested microorganisms to helium plasma in open atmosphere were discussed. 相似文献
160.
The n-butyl amine TPD measurement of Brönsted acidity for solid catalysts by simultaneous TG/DTG-DTA
The method for Brönsted acidity measurement based on TPD of alkyl amines desorption by gas-chromatography or thermogravimetry was adapted for simultaneous TG/DTG-DTA analysis. The acidity measurements were focused on the 12-tungstophosphoric acid (H3PW12O40) and its salts, especially with Cesium since these posses the highest Brönsted acidity and they are among the most interesting catalysts. The n-butyl amine (NBA) desorption takes place in three steps for CsxH3−xPW12O40, x = 0-2, and four steps for the Cs2.5H0.5PW12O40. The steps of desorption correspond to the release of NBA molecules in stages, as NBA or butene molecules resulted from the Hofmann elimination reaction and NH3 + H2O formed by decomposition of ammonium salt. The quantities of desorption products, C4H8 and NH3 + H2O, corresponding to the stages with the maximum desorption rates at 400-420 °C, respectively 560-600 °C, are in the stoichiometric ratio with the Brönsted acidity. 相似文献