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101.
We consider cold polar molecules confined in a helical optical lattice similar to those used in holographic microfabrication. An external electric field polarizes molecules along the axis of the helix. The large-distance intermolecular dipolar interaction is attractive but the short-scale interaction is repulsive due to geometric constraints and thus prevents collapse. The interaction strength depends on the electric field. We show that a zero-temperature second-order liquid-gas transition occurs at a critical field. It can be observed under experimentally accessible conditions. 相似文献
102.
G. Feldman M. Andersson J. R. M. Annand R. Codling K. Fissum K. Hansen S. Henshaw L. Isaksson M. A. Kovash M. Lundin D. E. Mittelberger L. Myers A. M. Nathan B. Schröder S. Stave H. R. Weller 《Few-Body Systems》2008,44(1-4):325-328
A new program of Compton scattering on deuterium is under way at the tagged-photon facility at MAX-Lab in Lund, Sweden. We will measure differential cross sections between 60° and 150° over the photon energy range 60–115?MeV in 5?MeV steps, with the ultimate goal of obtaining new precision information on the electric and magnetic polarizabilities of the neutron. 相似文献
103.
104.
Tobramycin and Nebramine as Pseudo‐oligosaccharide Scaffolds for the Development of Antimicrobial Cationic Amphiphiles 下载免费PDF全文
Yifat Berkov‐Zrihen Ido M. Herzog Raphael I. Benhamou Dr. Mark Feldman Kfir B. Steinbuch Pazit Shaul Dr. Shachar Lerer Dr. Avigdor Eldar Dr. Micha Fridman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4340-4349
Antimicrobial cationic amphiphiles derived from aminoglycoside pseudo‐oligosaccharide antibiotics interfere with the structure and function of bacterial membranes and offer a promising direction for the development of novel antibiotics. Herein, we report the design and synthesis of cationic amphiphiles derived from the pseudo‐trisaccharide aminoglycoside tobramycin and its pseudo‐disaccharide segment nebramine. Antimicrobial activity, membrane selectivity, mode of action, and structure–activity relationships were studied. Several cationic amphiphiles showed marked antimicrobial activity, and one amphiphilic nebramine derivative proved effective against all of the tested strains of bacteria; furthermore, against several of the tested strains, this compound was well over an order of magnitude more potent than the parent antibiotic tobramycin, the membrane‐targeting antimicrobial peptide mixture gramicidin D, and the cationic lipopeptide polymyxin B, which are in clinical use. 相似文献
105.
Doklady Mathematics - According to the Heyde theorem the Gaussian distribution on the real line is characterized by the symmetry of the conditional distribution of one linear form in independent... 相似文献
106.
107.
Stability of self-assembled monolayers on titanium and gold 总被引:1,自引:0,他引:1
Mani G Johnson DM Marton D Dougherty VL Feldman MD Patel D Ayon AA Agrawal CM 《Langmuir : the ACS journal of surfaces and colloids》2008,24(13):6774-6784
Methyl- and hydroxyl-terminated phosphonic acid self-assembled monolayers (SAMs) were coated on Ti from aqueous solution. Dodecyl phosphate and dodecyltrichlorosilane SAMs were also coated on Ti using solution-phase deposition. The stability of SAMs on Ti was investigated in Tris-buffered saline (TBS) at 37 degrees C using X-ray photoelectron spectroscopy, contact angle goniometry, and atomic force microscopy. For comparison purposes, a hydroxyl-terminated thiol SAM was coated on Au, and its stability was also investigated under similar conditions. In TBS, a significant proportion of phosphonic acid or phosphate molecules were desorbed from the Ti surface within 1 day, while the trichlorosilane SAM on Ti or thiol SAM on Au was stable for up to 7 days under similar conditions. The stability of hydroxyl-terminated phosphonic acid SAM coated Ti and thiol SAM coated Au was investigated in ambient air and ultraviolet (UV) light. In ambient air, the phosphonic acid SAM on Ti was stable for up to 14 days, while the thiol SAM on Au was not stable for 1 day. Under UV-radiation exposure, the alkyl chains of the phosphonic acid SAM were decomposed, leaving only the phosphonate groups on the Ti surface after 12 h. Under similar conditions, decomposition of alkyl chains of the thiol SAM was observed on the Au surface accompanied by oxidation of thiolates. 相似文献
108.
Archive for Rational Mechanics and Analysis - In order to accommodate general initial data, an appropriately relaxed notion of renormalized Lagrangian solutions for the Semi-Geostrophic system in... 相似文献
109.
A. A. Zezin V. I. Feldman A. V. Dudnikov S. B. Zezin S. S. Abramchuk S. I. Belopushkin 《High Energy Chemistry》2009,43(2):100-104
The specifics of X-ray-induced reduction of copper(II) ions in the polyacrylic acid-polyethyleneimine-copper(II) (PAA-PEI-Cu2+) complexes were studied. It was found that the action of radiation led to the effective reduction of Cu2+ in the PAA-PEI-Cu2+ films swollen in an aqueous-alcohol medium. The formation of metal nanoparticles in irradiated samples was revealed by electron microscopy and X-ray diffraction techniques. Analysis of ESR data has demonstrated that the Cu2+ reduction rate increases with an increase in the initial concentration of copper ions in the samples. Formal yields of the radiation-chemical reduction of Cu2+ in the PAA-PEI complex films were found to be quite high (>100 ions per100 eV of energy absorbed by the swollen film), which can be explained by involvement of the radiolysis products of aqueous alcoholic solutions (outer medium) in the reduction processes. 相似文献
110.
The shock reflection problem is one of the most important problems in mathematical fluid dynamics, since this problem not
only arises in many important physical situations but also is fundamental for the mathematical theory of multidimensional
conservation laws that is still largely incomplete. However, most of the fundamental issues for shock reflection have not
been understood, including the regularity and transition of different patterns of shock reflection configurations. Therefore,
it is important to establish the regularity of solutions to shock reflection in order to understand fully the phenomena of
shock reflection. On the other hand, for a regular reflection configuration, the potential flow governs the exact behavior
of the solution in C
1,1 across the pseudo-sonic circle even starting from the full Euler flow, that is, both of the nonlinear systems are actually
the same in a physically significant region near the pseudo-sonic circle; thus, it becomes essential to understand the optimal
regularity of solutions for the potential flow across the pseudo-sonic circle (the transonic boundary from the elliptic to
hyperbolic region) and at the point where the pseudo-sonic circle (the degenerate elliptic curve) meets the reflected shock
(a free boundary connecting the elliptic to hyperbolic region). In this paper, we study the regularity of solutions to regular
shock reflection for potential flow. In particular, we prove that the C
1,1-regularity is optimal for the solution across the pseudo-sonic circle and at the point where the pseudo-sonic circle meets the reflected shock.
We also obtain the C
2,α regularity of the solution up to the pseudo-sonic circle in the pseudo-subsonic region. The problem involves two types of
transonic flow: one is a continuous transition through the pseudo-sonic circle from the pseudo-supersonic region to the pseudo-subsonic
region; the other a jump transition through the transonic shock as a free boundary from another pseudo-supersonic region to
the pseudo-subsonic region. The techniques and ideas developed in this paper will be useful to other regularity problems for
nonlinear degenerate equations involving similar difficulties. 相似文献