Materials Literature
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Abstract Clothing for garments is designed to meet both the safety and the comfort of human beings. Porosity is considered to be one of the basic features representing a textile structure. The properties of fabrics were analyzed by determining the efficiency of fabric porosity. The woven fabric multi-layer structure,…
p-Hydroxybenzoate hydroxylase (PHBH) is a homodimeric enzyme in which each subunit noncovalently binds one molecule of FAD in the active site. PHBH is a model system for how flavoenzymes regulate reactions with oxygen. We report single-molecule fluorescence studies of PHBH in the absence of substrate that provide data…
It is well known that doping can greatly affect the ferroelectric properties of Bi4Ti3O12: however, the mechanisms of the doping effect, especially doping at the B site, are not well understood. The effect of B-site doping with different ion sizes and valences on the remanent polarization and fatigue endurance was inv…
The exchange-spring behavior found in Sm–Co (20nm)∕Fe epitaxial bilayer films was investigated by analyzing major hysteresis and recoil curves as a function of anneal conditions. The hard layer consists of nanocrystalline intermetallic Sm–Co hexagonal phases (majority phase Sm2Co7 with SmCo3 and SmCo5). Recoil curves,…
The effect of Co content on the phase formation, structure, and magnetocaloric effect of rapidly quenched La(Fe1−xCox)11.4Si1.6 with x=0 to 0.12 were investigated by x-ray diffractometry and magnetic measurements. Rietveld analyses indicate that with increasing Co content, the amount of the 1:13 phase increases from a…
Abstract A rare example of a mono‐aqua‐bridged copper( II ) dimer,namely [Cu 2 (μ 2 ‐H 2 O)L 2 (H 2 O) 2 ](ClO 4 ) 2 · 2H 2 O ( 1 ), has been synthesised and its structure determined by single‐crystal X‐ray diffraction. Each Cu II centre is in a square‐pyramidal surrounding formed by a Schiff base and a terminal H 2 O…
Ketol-acid reductoisomerase (KARI; EC 1.1.1.86) catalyzes two steps in the biosynthesis of branched-chain amino acids. Amino acid sequence comparisons across species reveal that there are two types of this enzyme: a short form (Class I) found in fungi and most bacteria, and a long form (Class II) typical of plants. Cr…
Structural characterization from powder diffraction of compounds not containing isolated molecules but three-dimensional infinite structure (alloys, intermetallics, framework compounds, extended solids) by direct space methods has been largely improved in the last 15 years. The success of the method depends very much…
Abstract A general method for the synthesis of so far unknown nonsymmetrically substituted N ‐aryl‐ N ′‐aryl′‐4,4′‐bipyridinium salts is presented ( Scheme 1 ). The common intermediate in all procedures is N ‐(2,4‐dinitrophenyl)‐4,4′‐bipyridinium hexafluorophosphate ( 1 ⋅ $\rm{\rm PF_6^ -}$ ). For the synthesis of non…
Water-soluble cobalt porphyrin 1Co and imidazole ligand 2 were synthesized. 1Co binds dioxygen in the presence of imidazole ligand 2 in aqueous solution. The formation of the oxygen adduct 2-1Co(O(2)) was studied using UV-vis and EPR spectroscopy. The impact of pH on the kinetic stability of the oxygen adduct was exam…
Abstract Under microwave irradiation, iron‐substituted polyoxotungstates (Fe‐POMs) catalyze cyclohexane oxygenation to A/K oil with 90–95% selectivity, unmatched turnover frequencies (40–400 h −1 ), and multi‐turnover regime (>1000 TON). Such a rapid reaction protocol allowed the screening of so‐called inorganic Fe…
A statistically based Plackett-Burman screening design identified milk whey and corn steep liquor concentrations as well as ionic strength (based on phosphate buffer concentration) as the three main independent components of the culture medium that significantly (p < 0.05) influenced biomass and poly(3-hydroxybutyrate…
The effects of varying the modulation index and the switching frequency on steel lamination core losses when excited with pulse width modulated waveforms are first investigated. A switched reluctance motor flux model is also developed and flux waveforms for different parts of the machine are synthesized. Using these f…
A new isoflavan, (3R)-6,2'-dihydroxy-7-methoxy-4',5'-methylenedioxyisoflavan, hildegardiol (1), and two known flavonoids, 2-hydroxymaackiain (2) and farrerol (3), were isolated from the antifungal root extract of Hildegardia barteri. The pterocarpan 2 was largely responsible for the observed antifungal activity.
A synthetic sequence to salts of N-alkylated pyridine-bridged 1,2,3-thiaselenazolo-1,2,3-thiaselenazolylium cations [2]+ (R1 = Me, Et; R2 = H) is described. The corresponding radicals 2 (R1 = Me, Et; R2 = H) can be generated from the cations by chemical or electrochemical reduction. Crystals of the two radicals are is…
A significant improvement of electromigration (EM) lifetime is achieved by modification of the preclean step before cap-layer deposition and by changing Cu cap/dielectric materials. A possible mechanism for EM lifetime enhancement was proposed. Cu-silicide formation prior to cap-layer deposition and adhesion of Cu/cap…
Two different approaches for studying sample’s contributions to diffraction-line broadening are analyzed by applying them to several nickel hydroxide samples. Both are based in the refinement of powder diffraction data but differ in the microstructural model used. The first one consists in the refinement of the powder…
Bismuth ferrite (BiFeO 3 ) thin films were fabricated by depositing sol–gel solutions on Pt/Ti/SiO 2 /Si(100) structures. X-ray diffraction (XRD) showed that a polycrystalline phase and also a small fraction of a secondary phase, Bi 2 Fe 4 O 9 , were present in the film. The nonperovskite secondary phase decreased wit…
Soil nitrogen-supply power (NSP), including nitrogen (N) mineralized from organic matter, for crop growth is an important criterion in evaluating soil quality. Ion-exchange membranes in the form of plant root simulator (PRS) probes were used to measure ammonium and nitrate release rates as a measure of NSP in 54 Saska…
The reaction of Rh(C2H4)2(acac) with the partially dehydroxylated surface of dealuminated zeolite Y (calcined at 773 K) and treatments of the resultant surface species in various atmospheres (He, CO, H2, and D2) were investigated with infrared (IR), extended X-ray absorption fine structure (EXAFS), and 13C NMR spectro…