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81.
82.
Ahmed Abouelaz Enrico Casadio Tarabusi Abdallah Ihsane 《Mediterranean Journal of Mathematics》2009,6(3):303-316
We study the Radon transform R on the discrete Grassmannian of rank-d affine sublattices of Z
n
for 0 < d < n, extending and building on previous work of the first- and third-named authors in codimension 1. By analogy with the integral
geometry on Grassmannians in R
n
, various natural questions are treated, such as definition and properties of R and its dual transform R
*, function space setting, support theorems and inversion formulas. 相似文献
83.
Franco Varsano Francesca Decker Enrico Masetti 《Monatshefte für Chemie / Chemical Monthly》2001,132(1):83-95
Summary. Ce-V mixed oxide films have been deposited by RF sputtering with the aim of increasing the Li charge capacity of counter
electrodes in smart windows. Such mixed oxides have shown high transmittance and optical passivity in the visible region.
After electrode pre-conditioning by cyclic voltammetry, a good electrochemical reversibility in LiClO4– propylene carbonate electrolyte was observed, and large Li-charge capacity under galvanostatic charging (up to 50 mCċcm−2) has been measured. The electrode charge capacity decreased after prolonged insertion-deinsertion cycles, whereas the photoptic
transmittance remained about constant. After 800 cycles the Li-charge capacity decreased to 40 mCċcm−2. The Li diffusion coefficient inside the films measured by electrochemical impedance and by galvanostatic titration ranged
from 10−11 cm2ċs−1 to 10−13cm2ċs−1. We observed that the Li charge capacity of the film electrodes is a function of the film deposition conditions, because
it increased with the vanadium oxide concentration in the target and with the oxygen content in the sputtering atmosphere.
Received June 23, 2000. Accepted (revised) August 7, 2000 相似文献
84.
Sabrina Brait Stefano Deabate Selby A. R. Knox Enrico Sappa 《Journal of Cluster Science》2001,12(1):139-173
A survey of the synthetic pathways and of the reactivity and catalytic activity of transition metal carbonyl clusters substituted with benzyne (and, for comparison, benzene and diene) ligands is given. Cluster-surface analogies are helpful in gaining an understanding of the homogeneous and heterogeneous catalytic behaviour of the clusters. 相似文献
85.
86.
Giuseppe Grasso Enrico Rizzarelli Giuseppe Spoto 《Journal of mass spectrometry : JMS》2009,44(5):735-741
The prominent role that insulin‐degrading enzyme (IDE) has on amyloidogenic peptides degradation has recently boosted a lot of attention toward this enzyme. Although many substrates are known to be degraded by IDE, little is known about the changes in the proteolytic activity of the enzyme upon modification of environmental factors. In a previous work we have already shown the great potentiality of atmospheric pressure/laser desorption ionization‐mass spectrometry (AP/MALDI‐MS) for studying the interaction between IDE and insulin. Here, the activity of IDE was investigated regarding cleavage sites' preferentiality upon modification of environmental factors by AP/MALDI‐MS. The roles that IDE/insulin concentration ratio, reaction time, adenosine 5′‐triphosphate (ATP) and metal ions (Zn and Cu) have on the insulin cleavage pattern produced by IDE are investigated and a plausible interpretation involving the proteolytic action of the different IDE oligomeric forms is proposed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
87.
In this paper, we prove that for non-effectively hyperbolic operators with smooth double characteristics exhibiting a Jordan
block of size 4 on the double manifold, the Cauchy problem is well-posed in the Gevrey 5 class, beyond the generic Gevrey
class 2 (see, e.g., [5]). Moreover, we show that this value is optimal, due to certain geometric constraints on the Hamiltonian
flow of the principal symbol. These results, together with results already proved, give a complete picture of the well-posedness
of the Cauchy problem around hyperbolic double characteristics. 相似文献
88.
89.
Carlo Marchioro Enrico Pagani H. Neunzert 《Mathematical Methods in the Applied Sciences》1986,8(1):328-344
We prove that two initially concentrated vortices with opposite vorticity of an incompressible ideal fluid moving in a two-dimensional bounded domain, remain concentrated during the time. The motion of their centers converges to the solution of the point vortex model with the corresponding initial conditions. 相似文献
90.
IDENTIFICATION OF MEMBRANE PROTEINS IMAGED BY ATOMIC FORCE MICROSCOPY USING A TEMPLATE MATCHING ALGORITHM 下载免费PDF全文
The atomic force microscope allows to image biological samples in their native environment. But the identification and the topography of individual randomly distributed membrane proteins is still a challenge. We used membranes of isolated vacuoles of barley mesophyll cells. Images at low resolution indicate that vacuoles spontaneously attach, rupture and finally adsorb completely as planar membrane to mica. Height profiles indicate that the membrane at the peripheral boundary exposes the extravacuolar surface to the scanning tip. At molecular resolution a template matching correlation algorithm was used to identify the most abundant membrane protein, the vacuolar H+-ATPase by the characteristic extravacuolar head of the transport molecule. The data indicate the possibility to analyse single randomly distributed membrane proteins in their native environment with the knowledge of a suitable template. 相似文献