Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Cyclic tension and compression testing has revealed that cracking behavior in structural steel subjected to plastic strain reversals is transitional from a fatigue to a ductile mode with the elevation of strain amplitude. The transition can be identified by the plastic strain accumulation pattern, the fractographic ap…
The mechanical properties of three grades of PMMA, one linear and two crosslinked, are investigated in tension below and above the glass transition temperature. It is found that strain-hardening decreases gradually with temperature in the glassy state, but keeps a significant value in the rubbery state. The results ar…
Solutions (1−5 wt %) of ultrahigh-molecular-weight atactic poly(acrylonitrile) (UHMW-PAN) in N, N‘ -dimethylformamide were crystallized to gel by quenching from 100 to 0 °C. The dried gel films exhibited poor ductility on straight tensile draw. However, they were ductile on solid-state coextrusion to an extrusion draw…
Catalytic properties of Pt−Ge intermetallic compounds, Pt 3 Ge, Pt 2 Ge, and PtGe, were studied for the H 2 −D 2 equilibration and the hydrogenation of 1,3-butadiene. Powdered Pt, Ge, and the Pt−Ge intermetallic compounds were treated with H 2 at 873 K to reduce their surface oxidized in air. XPS spectra measured afte…
The isothermal change of the magnetic entropy of a magnetically ordered material upon application of external magnetic field can be calculated from the temperature and field dependence of the magnetization or of the specific heat. The adiabatic temperature change, i.e., the magnetocaloric effect (MCE) can be measured…
The electrocatalytic oxidation of methanol on polypyrrole (PPy) film modified with platinum microparticles has been studied by means of electrochemical and in situ Fourier transform infrared techniques. The Pt microparticles, which were incorporated in the PPy film by the technique of cyclic voltammetry, were uniforml…
Deposition of copper thin films by an alternate supply of CuCl and Zn was examined. Due to a reversible dissolution of Zn into the Cu film, no self-limiting growth characteristic for the atomic layer epitaxy method could be achieved. The resulting films contained about 3 at. % zinc while chlorine residue contents were…
We have synthesized a series of [Mg 2+ (1 - x ) M 3+ x (OH) 2 ][TA 2 - (x/2) ]·zH 2 O (M 3+ = Ga 3+ or Al 3+ and TA = C 6 H 4 (COO - ) 2 ) from mixed-metal chloride solutions with initial M 3+ mole fractions of 0.20, 0.25, and 0.33, at constant pH values of 6.8, 7.7, 8.6, and 10.0. Terephthalate-containing products we…
Abstract Novel families of flexible, semiflexible and rigid crosslinked polyesters were prepared from modified natural oils such as soybean, rape‐seed and linseed oil. Maleinated oils were used as anhydride‐functional curing agents of epoxy resins such as bisphenol‐A‐diglycidylether and epoxidized natural oils. A new…
Enthalpy recovery data on poly(ether imide) from differential scanning calorimetry (DSC) is fit using the Moynihan−Tool−Narayanswamy model of structural recovery. A self-consistent phenomenological equation is used to describe the experimentally observed structure and temperature dependence of the relaxation time in b…
Highly exothermic direct reactions between elements boron and nitrogen at high pressures and temperatures yield technologically important forms of hexagonal and cubic boron nitride (BN). The crystal structures of the reaction products vary with pressure. Below 10 GPa, hexagonal BN is the product; cubic or wurzite BN f…
The synthesis and characterization of a series of bis(cyanide)( meso -tetraalkylporphyrinatoiron(III)), [Fe(T R P)(CN) 2 ] - where R is H, Me, Et, and i Pr, are reported. The 1 H NMR spectrum of the unsubstituted [Fe(T H P)(CN) 2 ] - shows a pyrrole signal at δ = −23.19 ppm (−25 °C) in CD 2 Cl 2, which is quite typica…
The supramolecular structures formed when anionic polyamidoamine starburst dendrimers, in the presence of low concentrations of spin probe surfactants, are added to aqueous solutions of nonlabeled cationic surfactants have been investigated by EPR spectroscopy. In order to obtain an overview of dendrimer/surfactant sy…
Birefringence is caused by both orientation of polymer chains and photoelasticity. These birefringences were compensated by random copolymerization of negative birefringent methyl methacrylate and positive birefringent benzyl methacrylate, but orientational and photoelastic zero birefringences were achieved with quite…
Plastic composite supports containing 50% agricultural products (oat hulls, soybean hulls, yeast extract, soybean flour, dried bovine erythrocytes, bovine albumin, and/or mineral salts) and 50% (wt/wt) polypropylene were produced by high-temperature twin-screw extrusion. The research employed two half sets of a five-f…
The tautomerism in solid phase was studied by near-edge X-ray absorption fine structure (NEXAFS) spectroscopy at the N K - and O K -edges and X-ray photoelectron spectroscopy (XPS) in the N1s and O1s regions for five N -salicylideneaniline derivatives: N, N‘ -disalicylidene-1,6-pyrenediamine (DSPY), N, N‘ -disalicylid…
Liposomes and immunoliposomes containing cytotoxic agents may be highly efficacious in intracavity therapy of malignancies confined principally to the peritoneal cavity. To assess the feasibility of this locoregional treatment, we prepared two derivatives of 5-fluorouridine (5-FUR), a highly cytotoxic metabolite of 5-…
We introduce a materials science tool for investigating refractory solids and melts: the electrostatic containerless processing system (ESCAPES). ESCAPES maintains refractory specimens of materials in a pristine state by levitating and heating them in a vacuum chamber, thereby avoiding the contaminating influences of…
The optical properties of a series of high refractive index polyphosphazenes were investigated. The wavelength-dependent change in refractive index (optical dispersion) associated with two selected polymers was examined using variable-angle spectroscopic ellipsometry. Values of the Abbé number for these polymers were…
Abstract Supramolecular structure of initially wet bacterial cellulose of Acetobacter xylinum has been investigated by X‐ray scattering including synchrotron radiation, transmission electron microscopy, and 13 C‐CP/MAS‐NMR‐spectroscopy. As a result a model is given of never dried swollen microfibrillar ribbons consist…