Materials Literature
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We report measurements of the low frequency conductivity and dielectric permittivity of quasi-one-dimensional organic (TMTTF) 2 X salts with non-centrosymmetrical anions X = ReO 4 and SCN. We show that the `structureless transition' at 227.5 K in (TMTTF) 2 ReO 4 is due to charge ordering and has a ferroelectric charac…
The ferroelectric insulator ${\mathrm{BaTiO}}_{3}$ can be electron-doped by substitution of divalent ${\mathrm{Ba}}^{2+}$ with trivalent ${\mathrm{La}}^{3+},$ creating d states at the transition-metal sites. The successive filling of the $3d$ Ti band initiates a sequence of electronic transitions. First, the system un…
The adsorption of CO at several adsorption temperatures T a in the range of 300−480 K on a reduced 4.7%Cu/Al 2 O 3 catalyst is studied by both FTIR spectroscopy and a volumetric method using a mass spectrometer as the detector. Only a linearly adsorbed CO species is detected with an IR band at 2092 cm -1 at 300 K afte…
Abstract 3‐Methacryloxypropylpolysilsesquioxane (MA‐PS) was prepared by acid‐ or base‐catalyzed hydrolytic polycondensation of 3‐methacryloxypropyltrimethoxysilane (MAS). MA‐PS coating film was prepared by dip‐coating on organic, metal and inorganic substrates, including poly(ethylene terephthalate), aluminum, stainle…
Site-selective carboxylate abstraction has been achieved from [Mn(12)O(12)(O(2)CR)(16)(H(2)O)(4)] complexes by treatment with HNO(3) in MeCN. The reaction of the R = Ph or CH(2)Bu(t)() complexes with 4 equiv of HNO(3) gives [Mn(12)O(12)(NO(3))(4)(O(2)CR)(12)(H(2)O)(4)] (R = CH(2)Bu(t) (6) or Ph (7)) in analytical puri…
Abstract The less‐volatile compounds forming a smoke emitted during the thermal degradation of poly(ethylene terephthalate) (PET) in different conditions were studied. Thermal degradation of PET was carried out within the temperature range of 200–700°C in both a nitrogen and an air atmosphere. The less‐volatile therma…
Polyelectrolyte complexes of poly(1,4-phenyleneethynylene carboxylate) (PPE) with 10 different cationic counterions were prepared. The counterions differed in their amphiphilicity, their headgroups (ammonium, pyridinium and sulfonium), and their alkyl chain lengths. It is shown that the optical properties of the PPE c…
Abstract The graft polymerization of acrylic acid was carried out onto poly(ethylene terephthalate) films that had been pretreated with argon plasma and subsequently exposed to oxygen to create peroxides. The influence of synthesis conditions, such as plasma treatment time, plasma power, monomer concentration, tempera…
Abstract Starch, a hydrophilic renewable polymer, has been used as a filler for environmentally friendly plastics for about 2 decades. Starch granules become swollen and gelatinized when water is added or when they are heated, and water is often used as a plasticizer to obtain desirable product properties. The objecti…
Abstract The effects of high‐energy radiation on sodium carboxymethylcellulose (CMC) with a degree of substitution of 2.2 were investigated. Moderate CMC concentrations formed hydrogels by intermolecular crosslinking. Significant influences on the results of irradiation, in addition to the concentration, were the dose…
As a part of an ongoing project on the production of composite materials based on poly(vinyl alcohol) (PVA) and polymeric materials from renewable resources, the present paper reports on the incorporation of agricultural waste materials as organic fillers in a film matrix based on PVA as continuous phase. In this stud…
Abstract Copolymer nanofibrils composed of pyrrole and aniline had been prepared by synthesizing the desired polymer within the pores of microporous anodic aluminum oxide (AAO) template membrane. To analyze their structure and properties, FTIR spectra were taken and thermogravimetric analysis (TGA) was applied. Also,…
Abstract Regenerated silk fibroin (RSF) was prepared by dissolving in a CaCl 2 /ethanol/H 2 O solvent system, freezing, and lyophilization. The effect of freezing temperature, alcohol addition, and molecular weight on the morphological and conformational changes were investigated through scanning electron microscopy,…
Recent contrasting observations for halogen (X)-bridged binuclear platinum complexes R_4[Pt_2(P_2O_5H_2)_4X]nH_2O, that is, pressure-induced Peierls and reverse Peierls instabilities, are explained by finite-temperature Hartree-Fock calculations. It is demonstrated that increasing pressure transforms the initial charg…
We report metal-encapsulated caged clusters of silicon from ab initio pseudopotential plane wave calculations using generalized gradient approximation for the exchange-correlation energy. Depending upon the size of the metal ( $M$) atom, silicon forms fullerenelike $M@{\mathrm{Si}}_{16}$, $M\phantom{\rule{0ex}{0ex}}=\…
Nanocoating, the covering of materials with a layer on the nanometer scale, or covering of a nanoscale entity, to form nanocomposites and structured materials using the sol−gel process is reviewed. Templates from spherical nanoparticles to complex bicontinuous networks are discussed where either the coated material or…
Preface. Introduction to Damping. Modeling the Dynamic Mechanical Behaviour of Viscoelastic Materials. The Effects of Temperature and Frequency on Complex Modulus Properties. Measurement of Complex Modulus Properties. Numerical Analysis of Measured Complex Modulus Data. The Complex Modulus Behaviour of Typical Polymer…
Scandium(III)-catalyzed oxidation of meso-meso-linked zinc(II)-porphyrin arrays (up to dodecamers) with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) led to efficient formation of triply meso-meso-, beta-beta-, and beta-beta-linked zinc(II)-oligoiporphyrins with 62 to 91% yields. These fused tape-shaped porphyrin ar…
Room-temperature single-electron transistors are realized within individual metallic single-wall carbon nanotube molecules. The devices feature a short (down to approximately 20 nanometers) nanotube section that is created by inducing local barriers into the tube with an atomic force microscope. Coulomb charging is ob…
The $3p$ photoelectron spectra of free Fe and Co atoms have been measured with the use of monochromatized synchrotron radiation and the atomic beam technique. These spectra reveal complex ${3p}^{\ensuremath{-}1}$ multiplet structures, which are discussed based on the predictions of configuration-interaction calculatio…