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21.
R.F. Holland M.C. Vasquez W.H. Beattie R.S. McDowell 《Journal of Quantitative Spectroscopy & Radiative Transfer》1983,29(5):435-438
From observations of the spectral absorbance of mixtures of nitric oxide in nitrogen at room temperature, we derive an integrated absorptivity for the NO fundamental band of 137.3±4.6 cm-2 atm-1 at 0°C. The indicated uncertainty is the estimated maximum error. 相似文献
22.
Achterberg A Ackermann M Adams J Ahrens J Andeen K Atlee DW Bahcall JN Bai X Baret B Bartelt M Barwick SW Bay R Beattie K Becka T Becker JK Becker KH Berghaus P Berley D Bernardini E Bertrand D Besson DZ Blaufuss E Boersma DJ Bohm C Bolmont J Böser S Botner O Bouchta A Braun J Burgess C Burgess T Castermans T Chirkin D Christy B Clem J Cowen DF D'Agostino MV Davour A Day CT De Clercq C Demirörs L Descamps F Desiati P Deyoung T Diaz-Velez JC Dreyer J Dumm JP Duvoort MR Edwards WR Ehrlich R 《Physical review letters》2006,97(22):221101
On 27 December 2004, a giant gamma flare from the Soft Gamma-Ray Repeater 1806-20 saturated many satellite gamma-ray detectors, being the brightest transient event ever observed in the Galaxy. AMANDA-II was used to search for down-going muons indicative of high-energy gammas and/or neutrinos from this object. The data revealed no significant signal, so upper limits (at 90% C.L.) on the normalization constant were set: 0.05(0.5) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the gamma flux and 0.4(6.1) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the high-energy neutrino flux. 相似文献
23.
For k a commutative ring, H a k‐bialgebra and A a right H‐comodule k‐algebra, we define a new multiplication on the H‐comodule A to obtain a twisted algebra” AT, T sumHom(H,End (A)). If T is convolution invertible, the categories of relative right Hopf modules over A and ATare isomorphic. Similarly a convolution invertible left twisting gives an isomorphism of the categories of relative left Hopf modules. We show that crossed products are invertible twistings of the tensor product, and obtain, as a corollary, a duality theorem for crossed products 相似文献
24.
Dr. James Jennings Dr. Erik J. Cornel Dr. Matthew J. Derry Dr. Deborah L. Beattie Dr. Matthew J. Rymaruk Oliver J. Deane Prof. Anthony J. Ryan Prof. Steven P. Armes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(27):10940-10945
Polymerization-induced self-assembly (PISA) enables the scalable synthesis of functional block copolymer nanoparticles with various morphologies. Herein we exploit this versatile technique to produce so-called “high χ–low N” diblock copolymers that undergo nanoscale phase separation in the solid state to produce sub-10 nm surface features. By varying the degree of polymerization of the stabilizer and core-forming blocks, PISA provides rapid access to a wide range of diblock copolymers, and enables fundamental thermodynamic parameters to be determined. In addition, the pre-organization of copolymer chains within sterically-stabilized nanoparticles that occurs during PISA leads to enhanced phase separation relative to that achieved using solution-cast molecularly-dissolved copolymer chains. 相似文献
25.
M. Beattie S. Dăscălescu ş. Raianu F. Van Oystaeyen 《Applied Categorical Structures》1998,6(2):223-237
We show that the two-sided two-cosided Hopf modules are in some case generalized Hopf modules in the sense of Doi. Then the equivalence between two-sided two-cosided Hopf modules and Yetter—Drinfeld modules, proved in [8], becomes an equivalence between categories of Doi—Hopf modules. This equivalence induces equivalences between the underlying categories of (co)modules. We study the relation between this equivalence and the one given by the induced functor. 相似文献
26.
Cuba-Chiem LT Huynh L Ralston J Beattie DA 《Langmuir : the ACS journal of surfaces and colloids》2008,24(15):8036-8044
Carboxymethyl cellulose (CMC), in solution and adsorbed on the surface of talc, has been studied with ATR FTIR spectroscopy as a function of the solution pH. The solution spectra enable the calculation of the extent of ionization of the polymer (due to protonation and deprotonation of the carboxyl group) at various pH values, yielding a value of 3.50 for the pK(app)(1/2) (pH at which half of all carboxyl groups are ionized) in a simple electrolyte solution and a value of 3.37 for the pK(app)(1/2) in solutions containing magnesium ions (3.33 x 10(-4) M). The spectra of the adsorbed layer reveal that CMC interacts with the talc surface through a chemical complexation mechanism, via the carboxyl groups substituted on the polymer backbone. The binding mechanism is active at all pH values down to pH 2 and up to pH 11. The adsorbed layer spectra reveal that protonation and deprotonation of the polymer are affected by adsorption, with an increase in the pK(app)(1/2) to a value of 4.80. Spectra of the adsorbed polymer were also acquired as a function of the adsorption time. Adsorption kinetic data reveal that the polymer most likely has two different interactions with the talc surface, with a stronger interaction with the talc edge through chemical complexation and a weaker interaction with the talc basal plane presumably through the hydrophobic interaction. 相似文献
27.
The Simplest Amino‐borane H2B=NH2 Trapped on a Rhodium Dimer: Pre‐Catalysts for Amine–Borane Dehydropolymerization
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Amit Kumar Nicholas A. Beattie Dr. Sebastian D. Pike Prof. Stuart A. Macgregor Prof. Andrew S. Weller 《Angewandte Chemie (International ed. in English)》2016,55(23):6651-6656
The μ‐amino–borane complexes [Rh2(LR)2(μ‐H)(μ‐H2B=NHR′)][BArF4] (LR=R2P(CH2)3PR2; R=Ph, iPr; R′=H, Me) form by addition of H3B?NMeR′H2 to [Rh(LR)(η6‐C6H5F)][BArF4]. DFT calculations demonstrate that the amino–borane interacts with the Rh centers through strong Rh‐H and Rh‐B interactions. Mechanistic investigations show that these dimers can form by a boronium‐mediated route, and are pre‐catalysts for amine‐borane dehydropolymerization, suggesting a possible role for bimetallic motifs in catalysis. 相似文献
28.
Whitby CP Djerdjev AM Beattie JK Warr GG 《Langmuir : the ACS journal of surfaces and colloids》2007,23(4):1694-1700
Droplet size distributions of concentrated, polydisperse oil-in-water emulsions have been measured using ultra small angle neutron scattering (USANS). The mean radii calculated by fitting a model for polydisperse hard spheres with excluded volume interactions to the USANS data were consistent with those derived from electroacoustics on diluted emulsions after correction for conductance behind the shear plane. The Porod radii measured by USANS were similarly consistent with the mean surface-area-weighted radii derived from electroacoustics, irrespective of the drop concentration or polydispersity. 相似文献
29.
Zhou J Beattie DA Ralston J Sedev R 《Langmuir : the ACS journal of surfaces and colloids》2007,23(24):12096-12103
Gold nanoparticles surface-coated with thyminethiol derivatives containing long hydrocarbon chains have been prepared. The diameter of the particles is 2.2 and 7.0 nm, respectively, with a relatively narrow size distribution. Thyminethiol derivatives are attached to the gold particle surfaces with thymine moieties as the end groups. The colloid stability of the gold nanoparticles as a function of the type and concentration of monovalent salt, pH, and particle size was investigated in alkaline, aqueous solutions. The gold particles are stable in concentrated NaCl and KCl solutions, but are unstable in concentrated LiCl and CsCl solutions. The larger gold particles are more sensitive to salt concentration and aggregate at lower salt concentrations. The reversible aggregation and dispersion of the gold particles can be controlled by changing the solution pH. The larger gold particles can be dispersed at higher pH and aggregate faster than the smaller particles, due to stronger van der Waals forces between the larger particles. Hydration forces play an important role in stabilizing the particles under conditions where electrostatic forces are negligible. The coagulation of the gold nanoparticles is attributed to van der Waals attraction and reduced hydration repulsion in the presence of LiCl and CsCl. 相似文献
30.
Li Zenghu 《数学物理学报(B辑英文版)》1999,19(2):121-126
The author proves a central limit theorem for the critical super Brownian motion, which leads to a Gaussian random field. In the transient case the limitingfield is the same as that obtained by Dawson (1977). In the recurrent case it is aspatially uniform field. The author also give a central limit theorem for the weightedoccupation time of the super Brownian motion with underlying dimension numberd 3, completing the results of Iscoe (1986). 相似文献