Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
The adsorption of methyl radicals has been studied by X-ray photoelectron spectroscopy and temperature-programmed desorption (TPD) on a clean Ni(100) surface, Ni(100) with a chemisorbed oxygen overlayer, and Ni(100) with a NiO(111) oxide overlayer. Methyl radical dosing at surface temperatures of 120−170 K produces ca…
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTDifferential Scanning Calorimetry Evidence for the Existence of a First-Order Thermal Transition in Ultraoriented at-Poly(acrylonitrile)Daisuke Sawai, Tetsuo Kanamoto, and Roger S. PorterView Author Information Department of Applied…
The crystal structure of yeast thymidylate kinase (TmpK) complexed with the bisubstrate inhibitor P1-(5'-adenosyl) P5-(5'-thymidyl) pentaphosphate (TP5A) was determined at 2.0 A resolution. In this complex, TmpK adopts a closed conformation with a region (LID) of the protein closing upon the substrate and forming a he…
The hydrolytic depolymerization of poly(ethylene terephthalate) (PET) was carried out in a stirred batch reactor at 235, 250, and 265 °C above its melting point and under autogenous pressure. The solid products which were mainly composed of terephthalic acid were analyzed by potentiometric titration and elemental anal…
A systematic study on the effect of various substituents at the 7- and/or 8-position on the redox properties of isoalloxazines (flavins) is reported. The redox properties of these flavin derivatives were studied by cyclic voltammetry in 100 mM, pH 7.4 HEPES and 200 mM, pH 10 borate buffers. The magnitude and direction…
Calmodulin (CaM) is an essential protein that exerts exquisite spatial and temporal control over diverse eukaryotic processes. Although the two half-molecule domains of CaM each have two EF-hands and bind two calcium ions cooperatively, they have distinct roles in activation of some targets. Interdomain interactions m…
A medium described by an imaginary potential (or imaginary (refractive index) ), that varies sinusoidally in one direction, acts as a volume grating for plane waves incident on it obliquely or normally. Two peculiar features are identified. First, if the potential is weak, so that there are only two significant diffra…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTHeterogeneous Oxidation of Allylic and Benzylic Alcohols Catalyzed by Ru−Al−Mg Hydrotalcites in the Presence of Molecular OxygenKiyotomi Kaneda, Toyokazu Yamashita, Tsuyoshi Matsushita, and Kohki EbitaniView Author Information Department of Chemical Science and Enginee…
Reactions of VCl 3 (THF) 3, bpy, and NaO 2 CR (R = Et, Ph; bpy = 2,2‘-bipyridine) in a 1:1:3 ratio in Me 2 CO give [V 4 O 2 (O 2 CR) 7 (bpy) 2 ](ClO 4 ) (R = Et, 1; R = Ph, 4 ) following addition of NBu n 4 ClO 4 . Use of 4,4‘-dimethyl- or 5,5‘-dimethylbipyridine (4,4‘-Me 2 bpy and 5,5‘-Me 2 bpy, respectively) and R =…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTElectropolymerization of Acenaphtho[1,2-k]fluoranthene Derivatives: Formation of a New Conductive Electroactive Electrochromic Hydrocarbon Ladder PolymerJeff D. Debad and Allen J. BardView Author Information Department of Chemistry and Biochemistry The University of Te…
The instability and periodic deformation of bilayer membranes during freezing processes are studied as a function of the difference of the shape energy between the high and the low temperature membrane states. It is shown that there exists a threshold stability condition, bellow which a planar configuration will be de…
A first principles theory of inelastic tunneling between a model probe tip and an atom adsorbed on a surface is presented, extending the elastic tunneling theory of Tersoff and Hamann. The inelastic current is proportional to the change in the local density of states at the center of the tip due to the addition of the…
This report describes the synthesis, characterization, and in vivo testing of several bifunctional contrast-enhancing agents for optical and magnetic resonance imaging (MRI) of experimental animals. These new agents integrate the advantages of both techniques since they can be visualized simultaneously by light and MR…
1. General Characteristics of Structural Phase Transitions in Crystals.- 1.1 First- and Second-Order Structural Phase Transitions.- 1.2 Structural Phase Transitions of Displacive and Order-Disorder Types.- 1.3 The Domain Structure.- 1.4 Ferroelectric Phase Transitions.- 1.5 Basic Types of Ferroelectric Crystals.- 2. P…
In the same thermogravimetric analyzer (TGA) under identical conditions, samples of pure, ash-free cellulose (i.e., Avicel PH-105, Whatman CF-11, Millipore ash-free filter pulp, and Whatman #42) obtained from different manufacturers undergo pyrolysis at temperatures which differ by as much as 30 °C. Thus, the pyrolysi…
Stable monolayers of soluble parent polypyrrole (Ppy) and mixed monolayers of cadmium stearate and Ppy were studied for the first time using surface pressure and surface potential isotherms. Ppy was obtained by chemical polymerization of the pyrrole monomer in the presence of dodecylbenzene sulfonic acid and character…
Polarized optical absorption and emission measurements are used to locate and assign 95 crystal-field energy levels split out of the 4f( )(8) electronic configuration of Tb(3+) in single crystals of Na(3)[Tb(oda)(3)].2NaClO(4).6H(2)O (where oda denotes an oxydiacetate ligand). The absorption measurements span the 235-…
Doped group 12 metal sulfides are important materials in the phosphor display industry. Control over the host lattice phase, composition, and dopant concentration is crucial for controlling the luminescence characteristics of these materials. Ternary thin films of Cd x Zn 1 - x S and ZnS:Mn were deposited by aerosol-a…
A series of monolithic poly[methyl methacrylate- co -3-(trimethoxysilyl)propyl methacrylate]−silica hybrid materials have been prepared via the sol−gel reactions. The fracture surfaces of the materials were systematically examined with atomic force microscopy (AFM) as a function of the silica content from ∼23 to 100 v…
New soluble polyimides were prepared from a series of diamines and a tetracarboxylic dianhydride with a benzhydrol unit, 3,3‘,4,4‘-benzhydrol tetracarboxylic dianhydride (BHTDA), by one-step method polymerization. The diamines containing flexible units, bulky substituents, and/or noncoplanar conformation unit were pre…