Characterizing Wool Keratin

Keratin from wool is a reactive, biocompatible, and biodegradable material. As the biological structural component of skin (soft keratins) and of nails, claws, hair, horn, feathers, and scales (hard keratins) pure keratin comprises up to 90% by weight of wool. Wool was treated in alkaline solutions to extract from 68% to 82% keratin within 2 to 5 hours of exposure at . The keratin products were water-soluble and were confirmed to contain intermediate filament and microfibrillar component-proteins of fractured, residual cuticle, and cortical cells. Oxidation of wool by peroxycarboximidic acid in alkaline hydrogen peroxide produced keratin products with distinct microcrystalline structures: descaled fibers, fibrous matrices, and lyophilized powders. Morphology and confirmation of peptide functionality were documented by SEM, Amino Acid Analysis, SDS-PAGE gel electrophoresis, MALDI-TOF/TOF, and FTIR analyses. The reactivity of keratin from wool models the reactivity of keratin from low-value sources such as cattle hair.

Cyclic Deformation Behavior and Fatigue Crack Propagation of Low Carbon Steel Prestrained in Tension

The tests were performed on low carbon steel plate. In the tension fatigue tests, two angle values (ϕ=0°andϕ=45°,ϕis the angle between the loading and the rolling direction) have been chosen. The influence of strain path change on the subsequent initial work softening rate and the saturation stress has been investigated. Dislocation microstructure was observed by transmission electron microscopy. It was found that the strain amount of preloading in tension has obviously affected the cyclic softening phenomenon and the initial cyclic softening rate. It was observed that the reloading axial stress forϕ=45°case increased more than that ofϕ=0°case, due to the anisotropism of Q235. In the fatigue crack propagation tests, the experimental results show that with increasing the pretension deformation degree, the fatigue crack growth rate increases, especially at the near threshold section.

The Studies of Conditions for Inducing Chirality to Cu(II) Complexes by Chiral Zn(II) and Ni(II) Complexes with Schiff Base

Recently, we have discovered that some chiral Schiff-base nickel(II) complexes induced d-d bands of CD spectra of some achiral copper(II) complexes. However, the novel phenomenon could be observed only a few systems of hybrid materials or limited conditions so far. In order to test conditions about copper(II) ions, we investigated model systems (1) metal-dendrimer (Cu-PAMAM; G4-NH2terminal) containing relatively small amount of copper(II) ions (4.5 equivalent to PAMAM) for modeling separated systems of achiral copper(II) complex from chiral Schiff-base nickel(II) or zinc(II) complexes, Bis(N-R-1-naphtylethyl-3,5-dichlorosalicydenaminato)nickel(II) or zinc(II) by polymer matrix. (2) equilibrium of copper(II)N-ethylethylenediamine complexes to measure absorption spectra of d-d band, pH, and electron conductivity during titration of copper(II) ions. The results showed that (1) 4.5Cu-PAMAM could not be induced their d-d bands by the chiral nickel(II) or zinc(II) complexes, which suggested that separation by polymers prevented from inducing CD peaks. (2) Although 36Cu-PAMAM was known, uncoordinated copper(II) ions excess to ligands mainly attributed to increase electron conductivity by remained ions in methanol solutions, which was not associated with intermolecular interaction or dipole moments being effective for the induced CD mechanism by using molecular recognition between neutral molecules of metal complexes.

Polymer Light-Emitting Diodes Efficiency Dependence on Bipolar Charge Traps Concentration

The efficiency of light-emitting diodes (LEDs) based on poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-1,4-benzo-{2,1′-3}-thiadiazole)], F8BT, is optimized upon simultaneous doping with a hole and an electron trapping molecule, namely, N,N′-Bis(3-methylphenyl)-N,N′-diphenylbenzidine and 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole, respectively. It is shown that, for devices with poly(3,4-ethylene dioxythiophene) doped with polystyrene sulfonic acid as hole-injection layer material and magnesium cathodes, the efficiency is nearly doubled (from ca. 2.5 to 3.7 cd/A) upon doping with ca. 0.34% by weight of both compounds.

Flow through a Two-Scale Porosity Material

Flow through a two-scale porous medium is here investigated by a unique comparison between simulations performed with computational fluid dynamics and the boundary element method with microparticle image velocimetry in model geometries.

Synthesis and Surface Properties of Silica Spheres with Core Shell Structure by One Convenient Method

Earlier, we have published a paper on the preparation of silica sphere using propanol as cosurfactant. We report here a highly cost-effective method of preparation of mesoporous silica spheres with core shell structure using sodium silicate as silica precursor, cetyltrimethyl ammonium bromide (CTAB) as surfactant, and methanol as cosurfactant. Thus after removal of the template by dissolutions or/and activation at higher temperature, mesoporous silica spheres with core shell structure were obtained. The products prepared with methanol to CTAB molar ratio 8.5 : 1 were confirmed to give best results. All the spherical products have very large surface area (∼589–1044 m2/g), pore volume (∼0.98–1.41 cm3/g), and ordered pore structure.

Preparation and Characterization of a Calcium Carbonate Aerogel

We report on a facile method for the preparation of a calcium carbonate aerogel consisting of aggregated secondary vaterite particles with an approximate average diameter of 50 nm. It was synthesized via a sol-gel process by reacting calcium oxide with carbon dioxide in methanol and subsequent supercritical drying of the alcogel with carbon dioxide. The resulting monolith was opaque, brittle and had overall dimensions of cm. It was characterized by X-ray powder diffraction, nitrogen adsorption method (BET), and scanning electron microscopy.

Process, Structure, and Properties of Electrospun Carbon Nanotube-Reinforced Nanocomposite Yarns

Carbon nanotubes (CNTs) are dispersed into polyacrylonitrile polymer solution and then assembled into continuous nanocomposite yarns through the drum-tape co-electrospinning process to facilitate the translation of CNT properties to higher order structures. We explore the dispersion of CNTs in a polymer matrix, the process of obtaining continuous yarn through electrospinning, and the surface morphology and mechanical properties of the nanocomposite yarn.

Application of Thermosensitive Peptide Copolymer Gels to Removal of Endocrine Disruptor

Poly(L-leucine)-block-poly(ethylene glycol)-block-poly(L-leucine) triblock copolymers were synthesized by a ring-opening polymerization ofα-amino acid N-carboxyanhydride with amino-terminated PEG as an initiator. The chloroform solution of these peptide copolymers showed a thermo-sensitive sol-gel transition. The transition temperature varied as a function of the length of peptide segments. Additionally, we used these peptide copolymers to remove an endocrine disruptor such as bisphenol A from its aqueous solution. As a result, it became clear that the peptide copolymer gel used in this study could capture bisphenol A efficiently.

The Determination of Bound Water in Waste Phosphatic Clay

Phosphatic clay is a by-product of phosphate strip mining, particularly in Florida, USA. This waste material occupies about 100 000 acres of land which could be utilized for other causes. Thus, its use as an alternating cementing material for the addition into the mixing matrix of cement paste and concrete to yield higher strength would be profitable for both materials involved. But the biggest drawback faced is that the phosphatic clay possesses high water holding capacity. The water is thus not available for mixing purposes when added to cement paste and concrete and is thus known as bound water. It is therefore essential to determine the amount of bound water to phosphatic clay which shall not be available for the hydration reaction of cement in cement paste and concrete.