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71.
B. P. Nicolsky V. I. Paramonova A. Stock H. Th. St. Britton C. Naegeli A. Tyabji Soerensen Walbum Ringer J. M. Kolthoff L. V. Wilcox B. Cavanagh B. Diethelm F. Foerster T. Callan J. A. Russell Henderson C. Robinson O. L. Evenson R. H. Nagel D. T. Mc Cutchen J. A. Atanasiu A. I. Verculescu R. R. Ralston C. H. Fellows K. S. Wyatt H. Seltz D. S. Mc Kinney K. Masaki C. del Fresno E. Mairlot E. Jimeno J. Ibarz 《Analytical and bioanalytical chemistry》1932,90(7-8):281-287
72.
Charge transfer dynamics between an adsorbed molecule and a rutile TiO(2)(110) surface have been investigated in three organometallic dyes related to multicenter water splitting dye complexes: Ru 535 (cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II)), Ru 455 (cis-bis(2,2'-bipyridyl)-(2,2'-bipyridyl-4,4'-dicarboxylic acid)-ruthenium(II)), and Ru 470 (tris(2,2'-bipyridyl-4,4'-dicarboxylic acid)-ruthenium(II)). The adsorption of the dye molecules on the rutile TiO(2)(110) surface has been studied using core-level and valence photoemission. Dye molecules were deposited in situ using ultrahigh vacuum electrospray deposition. Core-level photoemission spectra reveal that each complex bonds to the surface via deprotonation of two carboxylic groups. All three dye complexes show evidence of ultrafast charge transfer to the TiO(2) substrate using the core-hole clock implementation of resonant photoemission spectroscopy. 相似文献
73.
Fred B. Stocker Doyle Britton 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):798-800
Gold(I) cyanide forms complexes with imidazolidine‐2‐thione (etu) and dimethylthiourea (dmtu) with the formula [Au2(CN)2L2], i.e. the title complexes dicyano‐1κC,2κC‐bis(imidazolidine‐2‐thione)‐1κS,2κS‐digold(I)(Au—Au), [Au2(CN)2(C3H6N2S)2], and dicyano‐1κ2C‐bis(N,N′‐dimethylthiourea)‐2κ2S‐digold(I)(Au—Au), [Au2(CN)2(C3H8N2S)2]. In the etu complex, two approximately linear (etu)AuCN groups are held together by a weak homopolar Au—Au bond [3.117 (1) Å], with a torsion angle of 61 (3)° between the two groups. In the dmtu complex, an approximately linear Au(dmtu)2 group is bound to an approximately linear Au(CN)2 group by a weak heteropolar Au—Au bond [3.091 (1) Å], with a torsion angle of 83 (5)° between the two groups. 相似文献
74.
A slow positron lifetime study of the annealing behaviour of an amorphous silicon layer grown by MBE
J. Störmer P. Willutzki D. T. Britton G. Kögel W. Triftshäuser W. Kiunke F. Wittmann I. Eisele 《Applied Physics A: Materials Science & Processing》1995,61(1):71-74
We have studied MBE grown amorphous silicon, which was recrystallized at different temperatures for one hour, with a pulsed positron beam. A positron lifetime of 538±10 ps in the as-grown state is attributed to microvoids containing at least 10 vacancies. An incompletely recrystallized sample annealed at 500°C shows an additional long lifetime from ortho-positronium (o-Ps) pick-off annihilation. The o-Ps component disappears for samples, recrystallized at 700°C and above, and the defect lifetime steadily decreases with higher annealing temperature until a value of 310 ps is reached for the layer annealed at 1200°C. This value is explained by positron trapping at dislocations or small vacancy defects stabilized by dislocations or impurities.Paper presented at the 132nd WE-Heraeus-Seminar on Positron Studies of Semiconductor Defects, Halle, Germany, 29 August to 2 September 1994 相似文献
75.
76.
Milla M H?nninen Joonas Haapasalo Hannu Haapasalo Robert E Fleming Robert S Britton Bruce R Bacon Seppo Parkkila 《BMC neuroscience》2009,10(1):36
Background
Defective iron homeostasis may be involved in the development of some diseases within the central nervous system. Although the expression of genes involved in normal iron balance has been intensively studied in other tissues, little is known about their expression in the brain. We investigated the mRNA levels of hepcidin (HAMP), HFE, neogenin (NEO1), transferrin receptor 1 (TFRC), transferrin receptor 2 (TFR2), and hemojuvelin (HFE2) in normal human brain, brain tumors, and astrocytoma cell lines. The specimens included 5 normal brain tissue samples, 4 meningiomas, one medulloblastoma, 3 oligodendrocytic gliomas, 2 oligoastrocytic gliomas, 8 astrocytic gliomas, and 3 astrocytoma cell lines. 相似文献77.
78.
Alison J. Davenport Maria Forsyth Melanie M. Britton 《Electrochemistry communications》2010,12(1):44-47
Compositional and structural changes within an electrolyte solution above an electrochemically active metal surface have been visualised using magnetic resonance imaging (MRI) for the first time. In these proof-of-concept experiments, zinc metal was galvanically corroded in a saturated lithium chloride solution. Magnetic resonance relaxation maps were taken during the corrosion process and spatial variations in both T1 and T2 relaxation times were observed to change with time. These changes were attributed to changes in the speciation of zinc ions in the electrolyte. 相似文献
79.
NL Asfandiarov AI Fokin VG Lukin EP Nafikova GS Lomakin VS Fal'ko YV Chizhov 《Rapid communications in mass spectrometry : RCM》1999,13(12):1116-1123
A series of anthraquinone (C(14)O(2)H(8)) derivatives has been studied by means of electron capture negative ion mass spectrometry (ECNI-MS), photoelectron spectroscopy (PES), and AM1 quantum chemical calculations. Mean lifetimes of molecular negative ions M(-.) (MNI) have been measured. The mechanism of long-lived MNI formation in the epithermal energy region of incident electrons has been investigated. A simple model of a molecule (a spherical potential well with the repulsive centrifugal term) has been applied for the analysis of the energy dependence of cross sections at the first stage of the electron capture process. It has been shown that a temporary resonance of MNI at the energy approximately 0.5 eV corresponds to a shape resonance with lifetime 1-2.10(-13) s in the f-partial wave (l = 3) of the incident electron. The next resonant state of MNI at the energy approximately 1.7 eV has been associated with the electron excited Feshbach resonance (whose parent state is a triplet npi* transition). In all cases the initial electron state of the MNI relaxes into the ground state by means of a radiationless transition, and the final state of the MNI is a nuclear excited resonance with a lifetime measurable on the mass spectrometry timescale. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
80.
Doyle Britton Saliya A. deSilva Paul G. Gassman 《Journal of chemical crystallography》1999,29(8):949-953
Octahydroanthracenedicarbonitrile is monoclinic, space group P21/c, at 172 K, a = 4.723(7), b = 8.254(3), c = 16.190(7) Å, = 91.76(8)°, Z = 2, V = 630.8(12) Å3. The molecule, located on a center of symmetry, is disordered between the two senses of puckering in the aliphatic ring. The structure was also determined at 216, 256, and 297 K. The disorder increases with increasing temperature and can be described by a van't Hoff relationship with H = 5.2(3) kJ mol–1 and S = 13.8(12) J K–1 mol–1. 相似文献