Ultrashort laser pulses tightly focused inside a transparent material present an example of laser interaction with matter where all the laser-affected material remains inside the bulk, thus the mass is conserved. In this paper, we present the case where the high intensity of a laser pulse is above the threshold for optical breakdown, and the material is ionised in the focal area. We consider in detail a special case where a micro-explosion is formed at the boundary of a silicon surface buried under a 10-micron-thick oxidised layer, providing the opportunity to affect the silicon crystal by a strong shock wave and creating new material phases from the plasma state. We summarise the main conclusions on ultrafast laser-induced material modifications in confined geometry and discuss the prospects of confined micro-explosion for forming new silicon phases. 相似文献
Laser-induced forward transfer (LIFT) has been investigated for the transfer of a polymeric material. This study focuses on the comparison of the printing process using conventional LIFT printing with a simple square mask and an optimized LIFT technique using a double mask setup, i.e. smart beam shaping (SBS). The purpose is to optimize the energy repartition on the donor layer using a beam profile with over-intensities at the edges and low intensities in the center. This allows the incoming irradiation fluence on the donor layer to be kept as low as possible in the central area, thus preventing the organic pixels being damaged by laser irradiation. The influence of the film’s thickness on the SBS efficiency is discussed. 相似文献
A borylation reaction of aromatic diazonium salts has been optimized using titanocene and zirconocene derivatives as catalysts. The reaction employs diisopropylaminoborane as a borylating agent and proceeds smoothly at room temperature to provide arylboronates after methanolysis and transesterification with pinacol. The reaction mechanism has been found to proceed via a radical pathway. 相似文献
The synthesis of arylboronic ester derivatives from aryl chlorides by using aryl(amino)boranes is described. Palladium‐catalyzed coupling between aryl chlorides and diisopropylaminoborane leads to the formation of a C?B bond under mild conditions. A wide range of functional groups are tolerated, making this method particularly useful for the borylation of functionalized aromatics. 相似文献
In view of recent experiments on ultracold polarized fermions, the zero-range potential approach is generalized to situations where two-body scattering is resonant in the p-wave channel. We introduce a modified scalar product which reveals a deep relation between the geometry of the Hilbert space and the interaction. This formulation is used to obtain a simple interpretation for the transfer rates between atomic and molecular states within a two branches picture of the many-body system close to resonance. At resonance, the energy of the dilute gas is found to vary linearly with density. 相似文献
We examine the possible extensions to the Lipschitzian setting of the classical result on -convergence: first (approximation), if a sequence of functions of class from to converges uniformly to a function of class , then the gradient of is a limit of gradients of in the sense that ; second (regularization), the functions can be chosen to be of class and -converging to in the sense that . In other words, the space of functions is dense in the space of functions endowed with the pseudo-norm.
We first deepen the properties of Warga's counterexample (1981) for the extension of the approximation part to the Lipschitzian setting. This part cannot be extended, even if one restricts the approximation schemes to the classical convolution and the Lasry-Lions regularization. We thus make more precise various results in the literature on the convergence of subdifferentials.
We then show that the regularization part can be extended to the Lipschitzian setting, namely if is a locally Lipschitz function, we build a sequence of smooth functions such that
In other words, the space of functions is dense in the space of locally Lipschitz functions endowed with an appropriate Lipschitz pseudo-distance. Up to now, Rockafellar and Wets (1998) have shown that the convolution procedure permits us to have the equality , which cannot provide the exactness of our result.
As a consequence, we obtain a similar result on the regularization of epi-Lipschitz sets. With both functional and set parts, we improve previous results in the literature on the regularization of functions and sets.
The identification of specific protein markers for breast cancer would provide the basis for early diagnosis. Particularly, membrane and membrane-associated proteins are rich in targets for antibodies that may constitute suitable biomarkers of carcinogenesis. However, membrane proteins separation using 2-DE remains difficult. In this work, the breast cancer cell line MCF7 was used as source of proteins for the screening of potential cell membrane-associated antigens recognized by autoantibodies in patients with breast cancer and healthy volunteers. The protein extract obtained using trifluoroethanol (TFE) as cosolvent was compared to a total cell lysate protein extract prepared by a current technique. After 2-DE separation of the two extracts, their protein patterns clearly differed. About 63% of the proteins identified in the TFE-extract were predicted to possess at least one transmembrane domain. 2-D blots probed with sera from cancer patients or from healthy volunteers showed that, as expected, additional antigens were provided in the TFE-extract. Thus, the method described here appeared well suited for proteomic investigation of potential biomarkers undetected by current techniques. 相似文献