Materials Literature
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Abstract Biomass‐based polyurethane foams (PUFs) were degraded by glycolysis and the polyols recovered were reused to prepare a rigid polyurethane foam. Biomass‐based PUFs were prepared from liquefied wood or starch polyols and grafted products with polycaprolactone. The glycolysis was conducted using diethylene glyco…
Chymotrypsin is a prominent member of the family of serine proteases. The present studies demonstrate the presence of a native fragment containing 14 residues from Ile16 to Trp29 in alpha-chymotrypsin that binds to chymotrypsin at the active site with an exceptionally high affinity of 2.7 +/- 0.3 x 10(-11) M and thus…
Abstract A model is proposed for the layered structure of a polymer surface modified by elemental fluorine mixed with helium. The composition of the modified surface layer has been determined, and the thermodynamic compatibility of the surface layer, transition layer, and unmodified bulk of the polymer has been studie…
Bicarbonate ion reacts with the dinuclear nickel(II) complex containing the taec ligand (taec = N,N',N' ',N' ''-tetrakis(2-aminoethyl)-1,4,8,11-tetraazacyclotetradecane) in buffered aqueous solution to form the mu-eta(2),eta(2)-carbonate complex with a large effective binding constant for bicarbonate ion, log K(B) = 4…
Abstract The synthesis of polysulfide polymers with unsaturated and saturated units in the backbone and their characterization by Fourier transform infrared, NMR, gel permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry are reported. This is the first report on an analysis of th…
Using a simple experimental setup, the hydraulic permeability of fibrous nonwoven polyglycolic acid (PGA) scaffolds is studied after different degradation durations in PBS. The hydraulic permeability of the scaffolds increased with the degradation time. After being incubated for about 4 weeks, the permeability of the…
The multiple histidine-aspartate phosphorelay system plays a crucial role in cellular adaptation to environments in microorganisms and plants. Like kinase-phosphatase systems in higher eukaryotes, the multiple steps provide additional regulatory checkpoints with phosphatases. The Escherichia coli phosphatase SixA exhi…
Aniline sulfonic acid derivatives, o - and m -aminobenzenesulfonic, 3-amino-4-methoxybenzenesulfonic, 3-aniline-1-propane sulfonic acid, and 4-aniline-1-butane sulfonic acids, are incorporated via direct coprecipitation between the sheets of a layered double hydroxide (LDH) of intralamellar composition Cu 2 Cr(OH) 6 .…
AMP-forming acetyl-CoA synthetases (ACSs) are ubiquitous in all three domains of life. Here, we report the first characterization of an ACS from a hyperthermophilic organism, from the archaeon Pyrobaculum aerophilum. The recombinant ACS, the gene product of ORF PAE2867, showed extremely high thermostability and thermo…
The microstructure of die-cast magnesium alloys is highly non-uniform, which leads to a non-uniform distribution of the solidus/homologous temperature in the α(Mg) phase and a non-uniform distribution of deformation stresses and strains in the specimen during creep testing. Experimental observations suggest that signi…
Abstract A bifunctional compound [(4‐isocyanato‐4′(3,3‐dimethyl ‐2,4‐dioxo‐acetidino)diphenylmethane] (MIA) has been used as a building block for the synthesis of novel polyurea/malonamide dendrons. This is based on selectively sequential addition reactions of amines to isocyanato‐azetidine‐2,4‐diones. After incorpora…
Experimental high-energy transmission electron energy-loss absorption spectra from the oxygen $K$ edges of ${\mathrm{NbO}}_{2},\phantom{\rule{0.2em}{0ex}}{\mathrm{MoO}}_{2}$, and ${\mathrm{WO}}_{2}$ are compared with electronic structure calculations for the relevant empty states, based on the linear augmented plane w…
Density functional theory calculations have been carried out for hydrogen adsorption on the (001), (110), and (100) surfaces of Fe5C2. At 1/3 and 2/3 monolyer (ML) on (001), the most stable hydrocarbon species is CsH, while CsH and CsH3 can coexist at 1 ML. On (110), only dissociated hydrogen is found at 2/5 ML, while…
We describe a method to reliably pattern monolayers of iron nanoparticle (FeNP) colloids into submicron features for growth of single-walled carbon nanotubes (SWNTs) by chemical vapor deposition. Our process results in very clean patterns that are readily imaged by atomic force microscopy, which has allowed the observ…
MOTIVATION: The lack of standards for storage and exchange of data is a serious hindrance for the large-scale data deposition, data mining and program interoperability that is becoming increasingly important in bioinformatics. The problem lies not only in defining and maintaining the standards, but also in convincing…
Take a length of ribbon: Mesoporous silica ribbons that are typically 50–250 nm thick, 0.4–1.5 μm wide, and hundreds of micrometers long were prepared by a one-phase approach with cationic surfactants as templates under acidic conditions, and their cross-sections were studied by SEM and TEM techniques (see picture).
Synthesis, chain characteristics, and time-dependent viscoelastic response of polyhedral oligomeric silsesquioxanes (POSS)-containing hybrid polymers were investigated. Unlike many other reported POSS hybrid copolymers works, the POSS-grafted copolymers used in this study, although having different amounts of POSS att…
Switching signs: The polar structure of a tilted smectic C phase formed by a homologous series of bent-core mesogens changes from antiferroelectric to ferroelectric with increasing chain length. The polar switching of the banana-shaped molecules occurs by collective rotation around their long molecular axes (a) or by…
The effects of the OH group on the electronic and optical properties of single-wall carbon nanotubes were investigated using first principles electronic structure calculations. Our results confirm band-gap reduction of semiconductor carbon nanotubes up on addition of the OH group. An additional energy level emerges ne…
Using molecular-dynamics simulation, we calculate the distribution of atomic jumps in ${\mathrm{Cu}}_{33}{\mathrm{Zr}}_{67}$ in the liquid and glassy states. In both states the distribution of jump lengths can be described by a temperature-independent exponential of the length and an effective activation energy plus a…