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81.
Zdzislaw Brzeźniak Marek Capiński Franco Flandoli 《Probability Theory and Related Fields》1993,95(1):87-102
Summary The asymptotic behaviour of random dynamical systems in Polish spaces is considered. Under the assumption of existence of a random compact absorbing set, assumption supposed to hold path by path, a candidate pathwise attractorA() is defined. The goal of the paper is to show that, in the case of stationary dynamical systems,A() attracts bounded sets, is measurable with respect to the -algebra of invariant sets, and is independent of when the system is ergodic. An application to a general class of Navier-Stokes type equations perturbed by a multiplicative ergodic real noise is discussed in detail. 相似文献
82.
This paper proves a strong convergence theorem for sequences of pseudo-holomorphic maps from a Riemann surface to a symplectic
manifoldN with tamed almost complex structure. (These are the objects used by Gromov to define his symplectic invariants.) The paper
begins by developing some analytic facts about such maps, including a simple new isoperimetric inequality and a new removable
singularity theorem.
The main technique is a general procedure for renormalizing sequences of maps to obtain “bubbles on bubbles.” This is a significant
step beyond the standard renormalization procedure of Sacks and Uhlenbeck. The renormalized maps give rise to a sequence of
maps from a “bubble tree”—a map from a wedge Σ V S2 V S2 V ... →N. The main result is that the images of these renormalized maps converge in L1,2 ∪C° to the image of a limiting pseudo-holomorphic map from the bubble tree. This implies several important properties of the
bubble tree. In particular, the images of consecutive bubbles in the bubble tree intersect, and if a sequence of maps represents
a homology class then the limiting map represents this class. 相似文献
83.
The palladium catalysed cross-coupling reaction of aryl iodides and bromides with pinacolborane in 1,3-dialkylimidazolium tetrafluoroborates and hexafluorophosphates producing arylboronates is described. 相似文献
84.
Simple syntheses of syncarpurea (1) from syncarpic acid and the amino acids ornithine or citrulline are presented. 相似文献
85.
Surowiec I Baena JR Frank J Laurell T Nilsson J Trojanowicz M Lendl B 《Journal of chromatography. A》2005,1080(2):132-139
A flow-through microdispenser has been coupled to a micro HPLC separation system and used as a solvent elimination interface for Fourier transform infrared (FTIR) and Raman spectroscopic detection of the separated compounds. Using the microdispenser picoliter sized droplets can be generated and deposited on an appropriate target placed on a computerized x, y-stage. Evaporation of volatile solvent and buffer is rapid and allows analysis of the obtained dry deposits by various techniques. Due to the destruction free character of Raman and FTIR spectroscopy they can be applied sequentially to interrogate the same deposit. In the reported application five phenolic acids typically present in wine have been separated on a C-18 column technique using a mixture of water, methanol and acetic acid as mobile phase. For spectrum acquisition infrared and Raman microscopes have been used. The spectra recorded from the dried deposits of the separated compounds agreed well with the reference spectra of corresponding components. 相似文献
86.
Marek BryjakIrena Gancarz Gryzelda Po?niakW?odzimierz Tylus 《European Polymer Journal》2002,38(4):717-726
The effect of NH3 and NH3/Ar plasma on ultrafiltration polysulfone membranes have been studied. Results of contact angle, FTIR-ATR and X-ray photoelectron spectroscopy experiments clearly showed that both plasmas introduced hydrophilic, nitrogen- and oxygen-containing moieties on the polymer surface and that NH3/Ar plasma was more efficient. That plasma was also more aggressive--signs of strong etching could be seen on the SEM pictures. Redeposition of etched material seemed to take place inside the pores. On the contrary, ammonia plasma was soft and caused cleaning the surface and pores enlargement. Performance of ammonia plasma modified membranes was greatly improved and independent on solution pH. The last observation proved amphoteric character of the surface. NH3/Ar plasma treatment gave membranes of acidic surface and filtration indices not so good as for ammonia plasma. 相似文献
87.
A selective gas chromatographic detector for polynuclear aromatics based on ultraviolet fluorescence
A vapor-phase fluorescence detector for the analysis of mixtures of polynuclear aromatic ring systems has been developed. This system utilizes wide bandpass excitation and wide band emission filters, thus increasing sensitivity and decreasing the complexity of previously designed instruments. The sensitivity of the detector has been demonstrated to be at the nanogram level with reasonable precision. 相似文献
88.
89.
The room temperature reaction of (Bu4N)3V5O14 with PhPO3H2 in methanol yields the pentanuclear V(V) cluster (Bu4N)[V5O7(OCH3)2(PhPO3)5]·CH3OH (1·CH3OH). In contrast, the hydrothermal reaction of (Ph4P) [VO2Cl2], PhPO3H2 and (NH4)H2PO4 at 125°C for 96 hr yields the mixed valence V(IV)/V(V) species (Ph4P)2[V5O9(PhPO3)3(PhPO3H)2] (3). While the anions of both 1 and 3 exhibit a pentanuclear core, the structural consequences of 1-electron reduction of the fully oxidized cluster of 1 to produce 3 are quite dramatic, including reduction in coordination numbers at two vanadium sites and protonation of two phosphonate oxygen sites with concomitant structural reorganization. Crystal data: 1, monoclinic P21/n,a=12.167(2) Å,b=23.348(5) Å,c=22.508(5) Å,β=98.49(2)°,V=6323.9(19) Å3,Z=4,D calc=1.558 g cm?3; 3, triclinic, $P\bar 1$ ,a=13.478(3) Å,b=14.399(3) Å,c=23.638(5) Å,α=72.53(2)°,β=85.58(2)°,γ=69.88(4)°,V=4107.0(16) Å3,Z=2, Dcalc=1.479 g cm?3. 相似文献