Materials Literature
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The effect of physical cross-linking in candidate cycloaliphatic and hydrophobic poly(urethane urea) (4,4'-methylenebis(cyclohexylisocyanate), H(12)MDI/hydroxy-terminated polybutadiene, HTPBD/hexamethylenediamine, HDA) and poly(ether urethane urea)s (H(12)MDI/HTPBD-PTMG/HDA) on the in vitro calcification and blood-mat…
The stiffness and plasticity of boron nitride nanotubes are investigated using generalized tight-binding molecular dynamics and ab initio total energy methods. Due to boron nitride (BN) bond rotation effect, compressed zigzag BN nanotubes are found to undergo anisotropic strain release followed by anisotropic plastic…
Copolymerizations of ω-pentadecalactone (PDL) with trimethylene carbonate (TMC) were studied using chemical and enzyme catalysts. By using stannous octanoate, methylaluminoxane (MAO), or aluminum isopropoxide, copolymerizations of PDL with TMC with 1:1 feed ratio resulted in either homo-polyTMC or PDL/TMC block copoly…
The interaction between the antiferroelectric helix and an electric field applied perpendicular to its axis is investigated, both experimentally and theoretically. A two-stage switching process is observed: (i) in the pretransitional regime the helix distorts and then unwinds to form a nonhelical antiferroelectric sta…
Abstract The thermal stability of brominated isobutylene–isoprene rubber (BIIR) was investigated through studies of the elastomer and a model compound that accurately represented the reactive functionality within the polymer. An analysis of commercial BIIR and reaction products of brominated 2,2,4,8,8‐pentamethyl‐4‐no…
Abstract Nutshells from seven different sources (pistachio, hazelnut, almond, black walnut, English walnut, macadamia nut, pecan) were converted to granular activated carbons (GACs) by carbon dioxide activation. A portion of the GACs were oxidized with compressed air and the physical (yield, surface area, attrition),…
The photoinduced energy transfer processes in 1,4-phenylene-, 1,3-phenylene, 1,2-phenylene, and 4,4‘-biphenylene-linked and directly-linked Zn(II)-free base porphyrin heterodimers in THF were investigated by femtosecond transient absorption spectroscopy. The energy transfer rates were compared between TPP-type and OEP…
Four human genes, two of them encoding the proalpha1 and proalpha2 chains of type I procollagen and two of them the two types of subunit of prolyl 4-hydroxylase (4-PH), were integrated into the genome of Pichia pastoris. The proalpha1 and proalpha2 chains expressed formed type I procollagen molecules with the correct…
The hydrothermal reactions of Cu(SO4)·5H2O, MoO2, 1,10-phenanthroline, and the appropriate organodiphosphonate ligand yield organic−inorganic hybrid materials with one- or two-dimensional structures; the presence of cluster building blocks is illustrated by the structure of [{Cu(H2O)2(o-phen)}{Cu(o-phen)2}(Mo5O15)(O3P…
Magnetic properties of 2D systems of magnetic nanoobjects (2D regular lattices of the magnetic nanoparticles or magnetic nanostripes) are considered. The analytical calculation of the hysteresis curve of the system with interaction between nanoobjects is provided. It is shown that during the magnetization reversal sys…
The temperature and magnetic field dependence of the specific heat cp(T,H) in the superconducting mixed state as well as the upper critical field Hc2(T) have been measured for polycrystalline Y_xLu_{1-x}Ni_2B_2C and Y(Ni_{1-y}Pt_y)_2B_2C samples. The linear-in-T electronic specific heat contribution gamma(H)T exhibits…
We report first-principles calculations of the electronic band structure and lattice dynamics for the new superconductor MgB$_{2}$. The excellent agreement between theory and our inelastic neutron scattering measurements of the phonon density of states gives confidence that the calculations provide a sound description…
The fabrication, characterisation, and superconductivity of MgB2 thick films grown on stainless steel substrate were studied. XRD, SEM, and magnetic measurements were carried out. It was found that the MgB2 thick films can be fast formed by heating samples to 660 oC then immediately cooling down to room temperature. X…
The photoinduced 3D orientational structures in the films of liquid crystalline polyester, containing azobenzene side groups, are studied both experimentally and theoretically. By using the null ellipsometry and the UV absorption methods, preferential in-plane alignment of the azobenzene fragments and in-plane reorien…
One of the central dogmas in biochemistry is the view that the biologically active, three-dimensional structure of a protein is unique and exclusively determined by its amino acid sequence, and that the active conformation of a protein represents its state of lowest free energy in aqueous solution. Despite a large num…
Liquid crystals are states of condensed matter whose symmetries lie between those of 3-dimensionally peri-odic crystals and isotropic liquids. Thermotropic liquid crystalline phases are exhibited by a large number of organic compounds whose molecules have anisotropy of shape. A typical intermolecular energy responsibl…
[K(Q)][{ReH2(PMePh2)2}2(μ-H)3] is prepared by treatment of {ReH2(PMePh2)2}2(μ-H)4 with potassium hydride and a crown ether (Q = 18-crown-6 or 1,10-diaza-18-crown-6). The [K(1,10 diaza-18-crown-6)]+ salt contains NH...HRe protonic−hydridic bonds and has been characterized by 31P NMR, variable temperature 1H NMR, IR, an…
Ralstonia eutropha grows on and produces polyhydroxyalkanoates (PHAs) from fermentation acids. Acetic acid, one major organic acid from acidogenesis of organic wastes, has an inhibitory effect on the bacterium at slightly alkaline pH (6 g HAc/L at pH 8). The tolerance of R. eutropha to acetate, however, was increased…
We have previously reported on flat (lathlike) and helical single crystals grown from a smectic A* liquid crystalline (LC) phase of a main-chain nonracemic chiral polymer, PET(R*-9), synthesized from ( R )-(−)-4‘-{ω-[2-( p -hydroxy- o -nitrophenyloxy)-1-propyloxy]-1-nonyloxy}-4-biphenylcarboxylic acid. 1,2 In this pap…
Radiative and nonradiative relaxation processes after excitation by ultraviolet light were measured for o-, m-, and p- aryl ether dendrimers of fourth generation ( o-, m-, and p- Ar(L4) 2 ) by using fluorescent and thermal lens spectroscopies. Samples were dissolved in CH 2 Cl 2 to provide concentrations of a constant…