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Reactive Groups on Polymer-Covered Electrodes. 5. Synthesis and Cyclovoltammetric Analysis of 3-Substituted Thiophene Derivatives

Various functionalized polythiophene films on electrode surfaces were produced by electropolymerization. Starting from 3-(2-hydroxyethyl)thiophene ( 1 ) different ether and ester derivatives were synthesized: 3-(2-(benzyloxy)ethyl)thiophene ( 2 ), 3-[2-((triphenylmethyl)oxy)ethyl]thiophene ( 3 ), 3-[2-((trimethylsilyl…

Structure of Dehydrated Zeolite Li−LSX by Neutron Diffraction: Evidence for a Low-Temperature Orthorhombic Faujasite

Li−LSX (Li−faujasite with Si/Al = 1), cubic at room temperature, is orthorhombic ( Fddd ) at 10 K. In the room-temperature Fd 3̄ phase, Li cations in the supercage are evenly distributed between 2-fold-coordinated sites III and III‘, in close agreement with the cation distribution in Na−X. The cubic−orthorhombic phase…

Thermal plasmas

Although many thermal plasma processes have been developed for industrial applications, the wide acceptance as a manufacturing technology is prevented due to economical and competitive reasons, and/or reproducibility and reliability aspects. This paper is devoted to an assessment of the present knowledge in the follow…

Dislocation Based Fracture Mechanics

This book, by one of the major contributors to dislocation theory, gives a highly detailed look, using planar examples, into the materials science aspects of many important physical processes associated with fracture.The compendium of references provided by this excellently researched book will be invaluable for the a…

Chiral nematic droplets with parallel surface anchoring

Chiral nematic droplets of various radii $R$ and intrinsic pitch $P$ with parallel boundary conditions have been observed using a polarizing microscope. The visual appearances of the droplets have been compared with computer simulations from model director fields. It is found that the director configuration depends st…

Identification of the symmetry of phonon modes in CsPbCl3 in phase IV by Raman and resonance-Raman scattering

The first- and second-order Raman phonon spectra of CsPbCl3 were measured in phase IV using Raman and resonance-Raman scattering. Twelve Raman active phonons were resolved at 32, 35.5, 42, 52, 72, 90, 110, 115, 121, 189, 200.5, and 375 cm−1 and correlated to the phonon spectrum of CsPbCl3 in phase I. The highest frequ…

Reversible Photoswitching of Second-Order Nonlinear Optical Properties in an Organic Photochromic Crystal

Noncentrosymmetric crystals of photochromic N-salicylidene-4-bromoaniline are obtained and studied for their second-order nonlinear optical properties. Second harmonic light is generated and can be seen by the naked eye. Moreover, photochromism in the bulk state yields totally reversible photoswitching of the second h…

X-ray crystal-structure refinement of the nearly commensurate phase of1T−TaS2in(3+2)-dimensional superspace

The structure of the nearly commensurate phase of $1T\ensuremath{-}{\mathrm{TaS}}_{2}$ ${(1T}_{2}\ensuremath{-}{\mathrm{TaS}}_{2})$ has been refined in $(3+2)$-dimensional superspace against single-crystal x-ray-diffraction data collected at 300 K. The intensities of main reflections and satellites up to sixth order w…

Asymmetric gap soliton modes in diatomic lattices with cubic and quartic nonlinearity

Nonlinear localized excitations in one-dimensional diatomic lattices with cubic and quartic nonlinearity are considered analytically by a quasi-discreteness approach. The criteria for the occurence of asymmetric gap solitons (with vibrating frequency lying in the gap of phonon bands) and small-amplitude, asymmetric in…

Impact of cell shape and chain formation on nutrient acquisition by marine diatoms

Diatoms have evolved a multitude of morphologies, including highly elongated cells and cell chains. Elongation and chain formation have many possible functions, such as grazing protection or effects on sinking. Here, a model of diffusive and advective nutrient transport is used to predict impacts of cell shape and cha…

Displacive radiation effects in the monazite- and zircon-structure orthophosphates

Monazite-structure orthophosphates, including ${\mathrm{LaPO}}_{4},$ ${\mathrm{PrPO}}_{4},$ ${\mathrm{NdPO}}_{4},$ ${\mathrm{SmPO}}_{4},$ ${\mathrm{EuPO}}_{4},$ ${\mathrm{GdPO}}_{4},$ and natural monazite, and their zircon-structure analogs, including ${\mathrm{ScPO}}_{4},$ ${\mathrm{YPO}}_{4},$ ${\mathrm{TbPO}}_{4},$…

Evidence for a Functional Role of the Dynamics of Glycine-121 ofEscherichia coliDihydrofolate Reductase Obtained from Kinetic Analysis of a Site-Directed Mutant

Two-dimensional heteronuclear (1H-15N) nuclear magnetic relaxation studies of dihydrofolate reductase (DHFR) from Escherichia coli have demonstrated that glycine-121 which is 19 A from the catalytic center of the enzyme has large-amplitude backbone motions on the nanosecond time scale [Epstein, D. M., Benkovic, S. J.,…

The instrument response function in air-based scanning tunneling microscopy

The distinction between point and line resolution in transmission electron microscopy (TEM) arises because an ability to image sub-0.2 nm fringes is a necessary, but not a sufficient, condition for imaging individual atoms. In scanned tip microscopy, as in TEM, empirical data on instrument response should precede asse…

Nanoprocessing Based on Bicontinuous Microdomains of Block Copolymers: Nanochannels Coated with Metals

A novel process to produce a nanochannel comprised of a void in a polymer matrix is reported. The processing involves a selective degradation of one of the bicontinuous microdomain phases of microphase-separated block copolymers to create a continuous, tortuous hole having a diameter of nanometer scale (nanochannel) a…

Preclinical Evaluation of the Pharmacokinetics, Biodistribution, and Elimination of MS-325, a Blood Pool Agent for Magnetic Resonance Imaging

RATIONALE AND OBJECTIVES: The authors evaluate MS-325, a new albumin-targeted magnetic resonance imaging (MRI) contrast agent, for its pharmacokinetics, biodistribution, and elimination characteristics in multiple animal species. METHODS: Studies were performed in rats, rabbits, and nonhuman primates at intravenous do…

Targeting Dendrimer-Chelates to Tumors and Tumor Cells Expressing the High-Affinity Folate Receptor

RATIONALE AND OBJECTIVES: The authors developed a new method for delivering contrast agents to tumors and tumor cells. Gadolinium complexes of folate-conjugated dendrimer-chelates increased the longitudinal relaxation rate of tumor cells expressing the high-affinity folate receptor, hFR. The coupling of folate to poly…

Structural Effects upon Enzymatic Hydrolysis of Poly(butylene succinate-co-ethylene succinate)s

High molecular weight poly(butylene succinate- co -ethylene succinate)s, P(BS- co -ES)s, were obtained from succinic acid, 1,4-butanediol, and/or ethylene glycol through a polycondensation process. Enzymatic hydrolysis of hot-pressed copolyester films was carried out by utilizing lipases derived from a wide variety of…

Hydrogel-Coated Glassy Nanospheres: A Novel Method for the Synthesis of Shell Cross-Linked Knedels

A novel method was developed to prepare shell-cross-linked knedel-like structures (SCK's), which are double-layered polymer nanospheres, in a convenient three-step procedure: (1) polystyrene- b -poly(acrylic acid) ((DP n ) PS = 130, (DP n ) PAA = 120) copolymer was prepared by sequential anionic polymerization of styr…

Determination of microscopic parameters for nonresonant energy-transfer processes in rare-earth-doped crystals

A method for estimating the microscopic probability rate of phonon-assisted energy transfer between rare-earth $(3+)$ ions in solids was developed based on Dexter's theory for phonon-assisted energy transfer. The proposed method in this paper enables one to calculate the overlap integral from fundamental cross-section…