Materials Literature
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Abstract Polyvinyl alcohol amidoxime (PVAAO) chelate fiber prepared in our laboratory is a good adsorbent. Comparing with other adsorbents, it has many advantages, such as higher hydrophilicity, better adsorbability and easier synthesis. In this work, the synthesis course, structure and properties of PVAAO fiber have…
Abstract The crystallization behavior of polyolefins–nylon 6 polymer blends was studied by differential scanning calorimetry (DSC) measurements. In these blends, the crystallization of the minor component often starts with distinctly deeper supercooling than that of the pure polymer, and proceeds in several separate s…
We have studied the structural and magnetic properties of two compounds from the Me 3 2+ (Fe 3+ (CN) 6 - ) 2 3- .H 2 O family, where Me=Ni and Co. From x-ray analysis we find that the compounds crystallize in the face-centred cubic structure with the space group of F43m. Both the Fe and Me ions are coordinated octahed…
Epitaxy of Ge on Si(001) from undersaturated solutions demonstrates a novel principle: minimization of interfacial energy between solution and solid in a system provides the driving force for heteroepitaxy. Growth according to this principle leads to sharp heterointerfaces and Ge layers free of nucleation sites for di…
Li 0.5+0.5x Ti x Fe 2.5-1.5x O 4 , x<or=0.7, has been investigated using X-ray powder diffraction (17-70 degrees 2 theta ) and Mossbauer spectroscopy (300 and 77 K). All compositions show single cubic spinel structure with a constant lattice parameter of 0.833 nm. The room temperature Mossbauer spectra gave magnetic s…
Abstract Polyurethane anionomer dispersions were prepared from hydrogenated diphenylmethane diisocyanate (H 12 MDI) or isophorone diisocyanate (JPDI), poly(caprolactone) (PCL) diol, 1,4‐butane diol (BD), and dimethylolpropionic acid (DMPA). Upon neutralization of the DMPA with triethylamine (TEA), the NCO‐terminated p…
Examples of only the second known man-made isomer of porphyrin (1, Ar = C6H5, C6H4CH3) have recently been prepared by two groups working independently on opposite sides of the globe. These groups, led by L. Latos-Grażyński and H. Furuta, have shown that this isomer displays characteristics expected for a porphyrin whi…
The first Ti4Si4 heterocubane with twelve edges bridged by O atoms was prepared in good yields and characterized by X-ray crystallography. According to the IR spectrum of 1, the characteristic band for Ti-containing zeolites at approximately 960cm−1, the assignment of which had been debated, arises from the SiOTi st…
The wetting properties of thin polystyrene (PS) homopolymer films (polymerization index ${N}_{H}$) were studied on the surfaces of polyvinylpyridine-polystyrene (PVP-PS) block copolymer films (polymerization indices ${N}_{\mathrm{PS}}$ and ${N}_{\mathrm{PVP}}$) oriented into lamellae with the PS block present at the v…
Abstract Superheating and double‐melting endotherms are the characteristic melting behaviors of gel‐spun ultra‐high modulus and molecular weight polyethylene (UHMWPE) fibers in differential thermal analysis (DTA). A mostly orthorhombic structure with very little amorphous content is indicated by wide angle x‐ray scatt…
We have investigated electrical transport in undoped diamond films prepared by chemical vapor deposition. Using an electrolytic decoration scheme we prove that currents flow predominantly on grain boundaries. From the temperature and the frequency dependencies we conclude that hopping transport takes place. The conduc…
The thermal conductivity of SiO2 and TiO2 optical coatings are measured in the temperature range 80–400 K. For SiO2, the thermal conductivity of sputtered and evaporated films are 77% and 55% of the bulk value, respectively, independent of temperature. Similarly, the thermal conductivity of evaporated TiO2 is 63% of t…
The effect of Fe substitutions by rare-earth ions on magnetic and electrical properties of a Ni-Zn ferrite prepared by the classical method is investigated. A set of seven compounds with formula Ni 0.7 Zn 0.3 Fe 1.98 R 0.02 O 4 , where R identical to Yb, Er, Dy, Tb, Gd, Sm or Ce, was prepared. Emphasis is placed on cu…
The dielectric constant ε, loss tan δ, and conductivity σ of aluminium doped zinc—manganese ferrites of general formula Zn0.3Mn0.7Fe2−xAlxO4 (with x values ranging from 0.2 to 1.0) are studied as a function of frequency, in the range 5 to 500 kHz and in the temperature range 30 to 150 °C. All these samples are found t…
Results are given of an investigation of the absorption processes at the absorption edge of the ternary system (GaxIn1−x)2Se3 in the In-rich region. In E ∥ c polarization, the absorption coefficient for all investigated concentrations exhibits an exponential dependence on photon energy following Urbach's rule. The ana…
Single crystals of gallium-gadolinium garnet (GGG) irradiated by fluences of fast neutrons (0 to 3.8 × 1024 m−2) are investigated by X-ray and magnetic methods. It is found that irradiation with high fluences leads to complete amorphization of the samples. Besides, the samples recover their single crystalline structur…
The phase behaviour of chloro-aluminium phthalocyanine, chloro-indium phthalocyanine, bromo-indium phthalocyanine, dichloro-tin phthalocyanine, and dichloro-platinum phthalocyanine is studied using differential scanning calorimetry, X-ray diffraction, and X-ray fluorescence. The shape of the thermograms obtained in th…
A comparative analysis for the results obtained by force and energetic approaches, which are used in calculations of equilibrium position of misfit dislocations near interfaces, is performed. It is shown that a correct utilization of both approaches leads to similar results for the models which do not consider the fin…
FelI(HPO3)8(OH)6 AND Mnll(HPO3)8(OH)6 phosphite groups on the threefold axis gave either unstable refinements or chemically unreasonable structures, hence all were left in the same orientation as in the Fe compound.MPA would like to acknowledge the University of California, Santa Barbara, for the provision of a schola…
The structure of α-dicalcium silicate hydrate, \nCa_2(SiO_3OH)(OH), has recently been described and \nrefined [Y ano, Urabe, Ikawa, Teraushi, Ishizawa & \nUdagawa (1993). Acta Cryst. C49, 1555-1559] in space group P2_12_12_1 (orthorhombic; a = 9.487 (4), b = 9.179 (4), c = 10.666 (7) Å, Z = 8). It is b…