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91.
Sandra J. Rosenthal Ralph Jimenez Graham R. Fleming
P. V. Kumar
M. Maroncelli 《Journal of Molecular Liquids》1994,60(1-3):25-56We have investigated the ultrafast dynamics of methanol by time dependent fluorescent shift experiments and molecular dynamic simulations. The experiments were performed with two different probe molecules, 1-aminonaphthalene and coumarin 153. The molecular dynamic simulations employed these probes as well as small atomic and diatomic solutes. We find a previously unobserved fast decay component in the solvation response of methanol. The molecular dynamics results are in good agreement with this experimental result. The origin of this fast response and the linearity of the solvent response are discussed. 相似文献
92.
Let G be a non-discrete locally compact abelian group, and let M(G) be the convolution algebra of regular bounded Borel measures on G. Let Γ denote the dual group of G. Then the interior of the ?ilov boundary of M(G) is exactly Γ. The proof uses generalized Riesz products for the compact metrizable case and standard liftings from that case. 相似文献
93.
94.
Fernando Godoy Tamara Maldonado Erick Flores Nicolás Agurto Rodrigo González Guillermo Ferraudi Graham Lappin 《应用有机金属化学》2018,32(3)
We previously reported the synthesis and characterization of new organometallic chalcones derived from ferrocene, cyrhetrene and cymantrene functionalized with a benzo‐15‐crown‐5 fragment. The ferrocene and cyrhetrene chalcones have been investigated as chemosensors for metal ions with optical response in acetonitrile. Several metal ions were selected considering the diameter of the cavity and the charge‐to‐radius ratio of the cation. The stoichiometry of the complexes was determined using Job's method. It was found that Na+ and Ca2+ complexes have a 1:1 stoichiometry while a 2:1 (metaloligand‐to‐cation) stoichiometry was determined for Ba2+ and Pb2+ complexes. The association constants were calculated according to the stoichiometry of the complex and the results showed that they are directly affected by the electron‐withdrawing nature of the organometallic fragment. Moreover, complexes of ferrocenyl chalcone have larger association constants than those of the cyrhetrenyl analogue. This experimental observation is consistent with the electronic properties of the ferrocenyl fragment. 相似文献
95.
96.
Anna K. Yanchenko Graham Tierney Joseph Lawson Christoph Hellmayr Andrew Cron Mike West 《商业与工业应用随机模型》2023,39(3):292-309
Forecasting enterprise-wide revenue is critical to many companies and presents several challenges and opportunities for significant business impact. This case study is based on model developments to address these challenges for forecasting in a large-scale retail company. Focused on multivariate revenue forecasting across collections of supermarkets and product categories, hierarchical dynamic models are natural: these are able to couple revenue streams in an integrated forecasting model, while allowing conditional decoupling to enable relevant and sensitive analysis together with scalable computation. Structured models exploit multi-scale modeling to cascade information on price and promotion activities as predictors relevant across categories and groups of stores. With a context-relevant focus on forecasting revenue 12 weeks ahead, the study highlights product categories that benefit from multi-scale information, defines insights into when, how, and why multivariate models improve forecast accuracy, and shows how cross-category dependencies can relate to promotion decisions in one category impacting others. Bayesian modeling developments underlying the case study are accessible in custom code for interested readers. 相似文献
97.
In this paper we are concerned with solutions, in particular with univalent solutions, of the Loewner differential equation
associated with non-normalized subordination chains on the Euclidean unit ball B
n
in
\mathbbCn{\mathbb{C}^n}. The main result is a generalization to higher dimensions of a well known result due to Becker. Various particular cases
of this result have been recently obtained for subordination chains with normalization Df(0,t)=etIn{Df(0,t)=e^tI_n} or Df(0, t) = e
tA
, t ≥ 0, where
A ? L(\mathbbCn,\mathbbCn){A\in L(\mathbb{C}^n,\mathbb{C}^n)}. We also determine the form of the standard solutions to the Loewner differential equation associated with generalized spirallike
mappings. In the last section we obtain the form of the solution in the presence of coefficient bounds. 相似文献
98.
Abstract The infrared spectra (700–100 cm?1) of the complexes [M(ox)2(H2O)2] (ox = 8-hydroxyquinolinate anion, M = Mn, Fe, Co, Ni, Cu, Zn) are discussed. For the purposes of assignment of the metal ligand modes, deuterated 8-hydroxyquinoline-d 7 was prepared by the Skraup synthesis and the spectra of the deuterated complexes were compared with those of the unlabelled species. Furthermore, [64Zn(ox)2(H2O)2] and [68Zn(ox)2(H2O)2] were prepared by reaction of 64ZnSO4 and 68ZnSO4 with 8-hydroxyquinoline and the effects of metal isotope labelling on the spectra were examined and compared with earlier isotopic data on the nickel and zinc complexes. 相似文献
99.
Philip S. Hall Graham E. Jackson John R. Moss David A. Thornton Paul F. M. Verhoeven Gareth M. Watkins 《光谱学快报》2013,46(7):1247-1267
Abstract The infrared spectra (4000 - 50 cm?1) of the square planar rhodium(I) complexes cis-[Rh(CO)2 (pyridine) (X)] (X = Cl, Br) and their isotopomers with pyridine-d 5 and 13CO have been determined. Assignments are based on earlier studies on pyridine and its complexes and on the shifts in infrared bands which are caused by the isotopic substitutions employed. Normal coordinate analysis following the procedure of Becher and Mattes has been used to confirm the empirical assignments. The two v(RhC) bands are observed near 490 and 450 cm?1. v(RhN) is found near 210 cm?1 and v(RhX) occurs at 310 (X = Cl) and 235 (X = Br) cm?1. At frequencies below 200 cm?1, the bands are assigned to bending modes in the following sequence: δ (RhN) > δ (CRhC) > δ (RhCl) > γ (RhCl) > γ (RhN). 相似文献
100.
Yoshikazu Okamoto Graham J. Kemp Tomonori Isobe Eisuke Sato Yuji Hirano Junichi Shoda Manabu Minami 《Magnetic resonance imaging》2014
Several studies have proposed the cell membrane as the main water diffusion restricting factor in the skeletal muscle cell. We sought to establish whether a particular form of exercise training (which is likely to affect only intracellular components) could affect water diffusion. The purpose of this study is to characterise prospectively the changes in diffusion tensor imaging (DTI) eigenvalues of thigh muscle resulting from hybrid training (HYBT) in patients with non-alcoholic fatty liver disease (NAFLD). Twenty-one NAFLD patients underwent HYBT for 30 minutes per day, twice a week for 6 months. Patients were scanned using DTI of the thigh pre- and post-HYBT. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), the three eigenvalues lambda 1 (λ1), λ2, λ3, and the maximal cross sectional area (CSA) were measured in bilateral thigh muscles: knee flexors (biceps femoris (BF), semitendinosus (ST), semimembranous (SM)) and knee extensors (medial vastus (MV), intermediate vastus (IV), lateral vastus (LV), and rectus femoris (RF)), and compared pre- and post-HYBT by paired t-test. Muscle strength of extensors (P < 0.01), but not flexors, increased significantly post-HYBT. For FA, ADC and eigenvalues, the overall picture was of increase. Some (P < 0.05 in λ2 and P < 0.01 in λ1) eigenvalues of flexors and all (λ1-λ3) eigenvalues of extensors increased significantly (P < 0.01) post-HYBT. HYBT increased all 3 eigenvalues. We suggest this might be caused by enlargement of muscle intracellular space. 相似文献