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21.
The application of optoelectronic technologies and data transmission techniques, developed initially for the telecommunications market, to electronic processor systems offers to overcome interconnect limitations facing designers of these high performance systems. Optical interconnects offer increased data rates, low power consumption, compact size and inherent freedom from the effects of mutual coupling, line capacitance, EMI and topological constraints. This paper describes our investigation of two of the key technologies required for the practical implementation of optical interconnections, namely optoelectronic interface components (the optical bond pads), and the associated hybrid alignment techniques used in their assembly. 相似文献
22.
Graham?WigleyEmail author Martin?Goodwin Graham?Pitcher Damien?Blondel 《Experiments in fluids》2004,36(4):565-574
This paper describes a combined LDA, PDA and imaging analysis of the pressure swirl spray in the near-nozzle region of a GDI injector. This innovative approach in the use of multiple, complementary diagnostics facilitates the interpretation of a complex spray flow field.The LDA and PDA data were ensemble-averaged into time bins to produce comprehensive time-history and spatial profiles of liquid velocity, droplet velocity and size and the sample number. They indicated times at which the spray exhibited seven different characteristics. These were identified as: (a) pre-swirl spray, (b) spray cone develops, (c) spray cone relaxes, (d) maximum velocity in spray cone, (e) fully developed steady state, (f) spray cone collapses and (g) the spray detaches from the nozzle. The most effective method to present the spatial and temporal development of the spray was to superimpose the velocity vector and drop size field plots onto the spray images.This article is part of the special issue 11th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisboa, Portugal, July 2002, January 2004, Vol. 36, Issue no. 1 相似文献
23.
Let q be a power of a prime and n a positive integer. Let P(q) be a parabolic subgroup of the finite general linear group GL
n
(q). We show that the number of P(q)-conjugacy classes in GL
n
(q) is, as a function of q, a polynomial in q with integer coefficients. This answers a question of Alperin in (Commun. Algebra 34(3): 889–891, 2006) 相似文献
24.
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26.
Bolt PS Goodwin JW Ottewill RH 《Langmuir : the ACS journal of surfaces and colloids》2005,21(22):9911-9916
The preparation of zwitterionic latex particles is reported by using a mixed anionic and cationic initiator system without requiring surface-active agents. Isoelectric points were found from microelectrophoresis experiments and were in the pH range of 3.5-5. Close to the isoelectric point, the latices coagulated as expected, and good stability was achieved outside this narrow range. This range of stability was in good agreement with predictions from current theory. Redispersion after coagulation was found to be difficult as was expected for a hydrophobic colloid. The electrokinetic behavior did not result in the maximum in zeta potential at an electrolyte concentration of 1 mM unlike the situation for other hydrophobic polystyrene latex particles, and hence these systems may be even better models for other colloidal studies. 相似文献
27.
Adams CJ Connelly NG Goodwin NJ Hayward OD Orpen AG Wood AJ 《Dalton transactions (Cambridge, England : 2003)》2006,(29):3584-3596
The complexes [(H3N)5Ru(II)(mu-NC)Mn(I)Lx]2+, prepared from [Ru(OH2)(NH3)5]2+ and [Mn(CN)L(x)] {L(x) = trans-(CO)2{P(OPh)3}(dppm); cis-(CO)2(PR3)(dppm), R = OEt or OPh; (PR3)(NO)(eta-C5H4Me), R = Ph or OPh}, undergo two sequential one-electron oxidations, the first at the ruthenium centre to give [(H3N)5Ru(III)(mu-NC)Mn(I)Lx]3+; the osmium(III) analogues [(H3N)5Os(III)(mu-NC)Mn(I)Lx]3+ were prepared directly from [Os(NH3)5(O3SCF3)]2+ and [Mn(CN)Lx]. Cyclic voltammetry and electronic spectroscopy show that the strong solvatochromism of the trications depends on the hydrogen-bond accepting properties of the solvent. Extensive hydrogen bonding is also observed in the crystal structures of [(H3N)5Ru(III)(mu-NC)Mn(I)(PPh3)(NO)(eta-C5H4Me)][PF6]3.2Me2CO.1.5Et2O, [(H3N)5Ru(III)(mu-NC)Mn(I)(CO)(dppm)2-trans][PF6]3.5Me2CO and [(H3N)5Ru(III)(mu-NC)Mn(I)(CO)2{P(OEt)3}(dppm)-trans][PF6]3.4Me2CO, between the amine groups (the H-bond donors) at the Ru(III) site and the oxygen atoms of solvent molecules or the fluorine atoms of the [PF6]- counterions (the H-bond acceptors). 相似文献
28.
Total neutron scattering data from a powdered sample of MnO collected at 10 K have been analyzed using the reverse Monte Carlo method to refine the nuclear and magnetic structure. The results give the first unambiguous assignment of the average magnetic structure. The magnetic moments are aligned ferromagnetically within (111) sheets with the magnetization vectors of alternate sheets along axes parallel and antiparallel to the <112> directions, albeit with a small modulated out-of-plane component. Small displacements of Mn and O (modulated with the same periodicity) accompany the magnetic ordering and both atomic and magnetic structures may be described in the monoclinic space group C2. 相似文献
29.
Hamish H.‐M. Yeung Adam F. Sapnik Felicity Massingberd‐Mundy Michael W. Gaultois Yue Wu Duncan A. X. Fraser Sebastian Henke Roman Pallach Niclas Heidenreich Oxana V. Magdysyuk Nghia T. Vo Andrew L. Goodwin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(2):576-581
There is an increasing amount of interest in metal–organic frameworks (MOFs) for a variety of applications, from gas sensing and separations to electronics and catalysis. However, the mechanisms by which they crystallize remain poorly understood. Herein, an important new insight into MOF formation is reported. It is shown that, prior to network assembly, crystallization intermediates in the canonical ZIF‐8 system exist in a dynamic pre‐equilibrium, which depends on the reactant concentrations and the progress of reaction. Concentration can, therefore, be used as a synthetic handle to directly control particle size, with potential implications for industrial scale‐up and gas sorption applications. These findings enable the rationalization of apparent contradictions between previous studies of ZIF‐8 and opens up new opportunities for the control of crystallization in network solids more generally. 相似文献
30.
Conrad A. P. Goodwin Jing Su Thomas E. Albrecht‐Schmitt Anastasia V. Blake Enrique R. Batista Scott R. Daly Stefanie Dehnen William J. Evans Andrew J. Gaunt Stosh A. Kozimor Niels Lichtenberger Brian L. Scott Ping Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(34):12050-12050