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111.
Bowman MC Ballard TE Ackerson CJ Feldheim DL Margolis DM Melander C 《Journal of the American Chemical Society》2008,130(22):6896-6897
The design and synthesis of a multivalent gold nanoparticle therapeutic is presented. SDC-1721, a fragment of the potent HIV inhibitor TAK-779, was synthesized and conjugated to 2.0 nm diameter gold nanoparticles. Free SDC-1721 had no inhibitory effect on HIV infection; however, the (SDC-1721)-gold nanoparticle conjugates displayed activity comparable to that of TAK-779. This result suggests that multivalent presentation of small molecules on gold nanoparticle surfaces can convert inactive drugs into potent therapeutics. 相似文献
112.
Zassenhaus conjectured that any unit of finite order in the integral group ring of a finite group G is conjugate in the rational group algebra of G to an element in ±G. We review the known weaker versions of this conjecture and introduce a new condition, on the partial augmentations of the powers of a unit of finite order in , which is weaker than the Zassenhaus Conjecture but stronger than its other weaker versions.We prove that this condition is satisfied for units mapping to the identity modulo a nilpotent normal subgroup of G. Moreover, we show that if the condition holds then the HeLP Method adopts a more friendly form and use this to prove the Zassenhaus Conjecture for a special class of groups. 相似文献
113.
C. S. Edwards H. S. Margolis G. P. Barwood S. N. Lea P. Gill W. R. C. Rowley 《Applied physics. B, Lasers and optics》2005,80(8):977-983
A pair of 1.5 μm semiconductor laser frequency standards have been developed for optical telecommunications use, stabilised to Doppler-free transitions of the ν1 + ν3 and ν1 + ν2 + ν4 + ν5 combination bands of 13C2H2. The Allan deviation σ/f for a laser locked to line P(10) of the former band follows a slope of 1.6 × 10−12τ−1/2, reaching a minimum of 5.7 × 10−14 at τ = 4000 s. The absolute frequencies of 61 lines of the ν1 + ν3 band and 43 lines of the ν1 + ν2 + ν4 + ν5 band, covering the spectral region 1520 nm to 1552 nm, have been measured by use of a combined frequency chain and femtosecond comb, together with a passive optical frequency comb generator. The mean uncertainties for the line frequencies within each band are 1.4 kHz for the ν1 + ν3 band and 1.9 kHz for the ν1 + ν2 + ν4 + ν5 band, representing improvements on the precision of previously published data by factors of 100 and 104, respectively. Improved values of the rotational constant B″ and centrifugal distortion coefficients D″, H″ and L″ of the vibrational ground state are presented.This article is published with the permission of the Controller of HMSO and the Queen’s Printer of Scotland 相似文献
114.
The (·)reg construction was introduced in order to make an arbitrary semigroup S divide a regular semigroup (S) reg which shares some important properties with S (e.g., finiteness, subgroups, torsion bounds, J-order structure). We show that (S) reg can be described by a rather simple complete string rewrite system, as a consequence of which we obtain a new proof of the normal form theorem for (S) reg. The new proof of the normal form theorem is conceptually simpler than the previous proofs. 相似文献
115.
We study the maximal subgroups of free idempotent generated semigroups on a biordered set by topological methods. These subgroups are realized as the fundamental groups of a number of 2-complexes naturally associated to the biorder structure of the set of idempotents. We use this to construct the first example of a free idempotent generated semigroup containing a non-free subgroup. 相似文献
116.
Margolis HS 《Chemical Society reviews》2012,41(15):5174-5184
Over the past twelve years, notable advances have occurred in a diverse range of scientific areas following the development of femtosecond optical frequency combs. Compared to a conventional laser source, the distinguishing feature of a femtosecond comb is that it provides a broadband source with well-defined phase coherence across the optical spectrum. This makes it a unique tool for spectroscopic applications, simultaneously providing high spectral resolution and broad spectral coverage. This tutorial review provides an introduction to femtosecond optical frequency combs, covering their principles of operation and examples of how they can be applied to spectroscopy. In this way it aims to demonstrate their potential as a versatile spectroscopic tool that could play a very significant role in future advances in the chemical sciences. 相似文献
117.
Y. Afek C. Leroy B. Margolis J. Trischuk B. A. Campbell 《Zeitschrift fur Physik C Particles and Fields》1980,6(3):251-264
Cross Sections for the production of charm and bottom in neutrino (antineutrino) reactions are calculated in asymptotically free Quantum Chromodynamics. Total and differential cross sections are given for Cabibbo suppressed valence and Cabibbo favoured strange quark ocean production. The next order Quantum Chromodynamic correction to the charm production cross section is calculated. Arguments and estimates for the distribution of final state charmed hadrons are considered. 相似文献
118.
119.
L. V. Nikisha R. I. Moshkina S. S. Polyak L. Ya. Margolis V. I. Vedeneev 《Russian Chemical Bulletin》1978,27(1):41-45
Conclusions The inhibiting action of Al2O3 and KSK silica gel on the homogeneous oxidation of ethane at 320°C is due to the breakdown of formaldehyde, the branching agent for the oxidation reaction, on these catalysts.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 50–55, January, 1978. 相似文献
120.