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71.
We prove that if G is a discrete group that admits a metrically proper action on a finite-dimensional CAT(0) cube complex X, then G is weakly amenable. We do this by constructing uniformly bounded Hilbert space representations π
z
for which the quantities
z
ℓ
(g) are matrix coefficients. Here ℓ is a length function on G obtained from the combinatorial distance function on the complex X. 相似文献
72.
In this paper we introduce a structure called the Markovian tree (MT). We define the MT and explore its alternative representation
as a continuous-time Markovian Multitype Branching Process. We then develop two algorithms, the Depth and Order algorithms
to determine the probability of eventual extinction of the MT process. We show that both of these algorithms have very natural
physically intuitive interpretations and are analogues of the Neuts and U algorithms in Matrix-analytic Methods. Furthermore,
we show that a special case of the Depth algorithm sheds new light on the interpretation of the sample paths of the Neuts
algorithm. 相似文献
73.
Nigel J. Brookes David C. Graham Gemma Christian Robert Stranger Brian F. Yates 《Journal of computational chemistry》2009,30(13):2146-2156
Electronic structure methods have been combined with the ONIOM approach to carry out a comprehensive study of the effect of ligand bulk on the activation of dinitrogen with three‐coordinate molybdenum complexes. Calculations were performed with both density functional and CCSD(T) methods. Our results show that not only is there expected destabilization of the intermediate on the pathway due to direct steric interactions of the bulky groups, but also there is significant electronic destabilization as the size of the ligand increases. This latter destabilization is due to the inability of the molecule to accommodate a rotated amide group bound to the molybdenum once the amide reaches a certain size. This destabilization also leads to a clear preference for the triplet intermediate (rather than the singlet intermediate) for bulky substituents which is in agreement with experiment. Overall, the calculated reaction profile for the bulky substituents shows a good correlation with the available experimental data. © 2009 Wiley Periodicals, Inc. J Comput Chem 2009 相似文献
74.
75.
Antony V. Wilson Timothy Nguyen Felix Brosi Xuefeng Wang Lester Andrews Sebastian Riedel Adam J. Bridgeman Nigel A. Young 《ChemInform》2016,47(14):no-no
Binary palladium fluorides from PdF to PdF6 are investigated by matrix‐isolation methods using thermal evaporation and laser ablation to generate Pd atoms for reaction with F2‐doped Ar and Ne matrices as well as neat F2 matrices. 相似文献
76.
George A. Koutsantonis Jackson Lee Nigel A. Lengkeek Gareth L. Nealon Brian W. Skelton Allan H. White 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(1-2):61-66
The synthesis and single-crystal x-ray structure determination of two new trinuclear metal complexes is detailed. In these we utilise the appended iminodiacetate substituents, in [Co(CH3)NH(CH2CO2H)2sar]3+, to act as a focus for coordination of other metal ions. Thus, we have made complexes of Cu and Ni utilising the basic carbonates of these metals and [Co(CH3){N(CH2CO2H)2}sar]3+ (CoL2) which gave rise to ((CoL2–2H+)2M), M = Cu and Ni. The electrochemical study of the latter was inconclusive and provides the impetus for further study. 相似文献
77.
78.
The preparation of bis-protected phloroglucinol derivatives from a range of protected resorcinol substrates is presented. Functionalization was achieved via a two-step, one-pot iridium-catalyzed C-H activation/borylation/oxidation protocol. Our system gave high conversions to the arylboronic esters and good yields of the desired phenols following subsequent oxidation. A range of common protecting group categories was studied including alkyl, silyl, ether and ester. 相似文献
79.
Kathryn L. Gilroy Sarah A. Cumming Andrew R. Pitt 《Analytical and bioanalytical chemistry》2010,398(1):547-554
Quantum dots (Qdots) are fluorescent nanoparticles that have great potential as detection agents in biological applications.
Their optical properties, including photostability and narrow, symmetrical emission bands with large Stokes shifts, and the
potential for multiplexing of many different colours, give them significant advantages over traditionally used fluorescent
dyes. Here, we report the straightforward generation of stable, covalent quantum dot–protein A/G bioconjugates that will be
able to bind to almost any IgG antibody, and therefore can be used in many applications. An additional advantage is that the
requirement for a secondary antibody is removed, simplifying experimental design. To demonstrate their use, we show their
application in multiplexed western blotting. The sensitivity of Qdot conjugates is found to be superior to fluorescent dyes,
and comparable to, or potentially better than, enhanced chemiluminescence. We show a true biological validation using a four-colour
multiplexed western blot against a complex cell lysate background, and have significantly improved previously reported non-specific
binding of the Qdots to cellular proteins. 相似文献
80.
Payam Zahedi Iraj Rezaeian Seyed‐Omid Ranaei‐Siadat Seyed‐Hassan Jafari Pitt Supaphol 《先进技术聚合物》2010,21(2):77-95
Wound dressings have experienced continuous and significant changes since the ancient times. The development starts with the use of natural materials to simply cover the wounds to the materials of the present time that could be specially made to exhibit various extraordinary functions. The modern bandage materials made of electrospun biopolymers contain various active compounds that are beneficial to the healing of wounds. These materials are fibrous in nature, with the size of fibers segments ranging from tens of nanometers to micrometers. With the right choices of biopolymers used for these fibrous materials, they could enhance the healing of wounds significantly compared with the conventional fibrous dressing materials, such as gauze. These bandages could be made such that they contain bioactive ingredients, such as antimicrobial, antibacterial, and anti‐inflammatory agents, which could be released to the wounds enhancing their healing. In an active wound dressing (AWD), the main purpose is to control the biochemical states of a wound in order to aid its healing process. This review provides an overview of different types of wounds, effective parameters in wound healing and different types of wound dressing materials with a special emphasis paid to those prepared by electrospinning. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献