Corrosion and preservation of bronze artifacts
Alloys, bronze, and the corrosion and protection of copper and bronze.
Materials Literature
文献浏览
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。
The study of grain boundary thickness using electron diffraction techniques
An electron diffraction technique has been developed to study the thickness of grain boundaries in polycrystalline specimens. Grain boundaries with a periodic structure in Al2O3, Cu-Bi and Au, were examined in an edge-on orientation using electron microscopy and diffraction. Each boundary gave rise to streaks in the d…
Polymerization of Silicic Acid Adsorbed on Iron(III) Hydroxide
Abstract Adsorption of silicic acid on iron(III) hydroxide from aqueous solution and polymerization of adsorbed silicic acid were affected by pH, concentration of silicic acid before and after adsorption, or the relative amount of silicic acid and iron(III) hydroxide. The amount of adsorbed silicic acid and the rate o…
Small-molecule cyclic models for the synthesis of new polyphosphazenes: side-group construction via lithiophenoxy derivatives
Hexa(p-lithiophenoxycyclotriphosphazene) has been synthesized as an intermediate for the covalent attachment of metallo-, phosphino, carboxylato, alkyl, or tertiary alcohol units to the side group structure. These reactions are models for the preparation of the corresponding phosphazene high polymers.
Purification and properties of glucose isomerase of Actinoplanes missouriensis
Abstract Actinoplanes missouriensis produces an intracellular soluble glucose Isomerase. The soluble enzyme can be purified by a DEAE‐cellulose beads columm with a onestep salt elution. The purified enyzme exhibited a molecular weight of approximately 80,000 daltons, being composed of two identical subunits of about 4…
Measurement of radiation damage by electron energy‐loss spectroscopy
SUMMARY Inner shell ionization edges in the energy‐loss spectrum were used to measure the loss of gaseous elements from thin samples of nitrocellulose, polyvinyl formal, copper phthalocyanine, graphite bisulphate and sodium chloride during exposure to 80 keV electrons. The irradiation kinetics were measured for electr…
Optimization of oxide-semiconductor/base-semiconductor solar cells
In order to get the maximum output from oxide-semiconductor/base-semiconductor solar cell, one has to incorporate an ultrathin insulating layer so that the resulting configuration is a semiconductor-insulator-semiconductor (SIS) diode. The performance of such SIS diodes is equivalent to a metal-insulator-semiconductor…
The melt elasticity of polymer blends: Polystyrene/poly(methyl methacrylate)
Samples of general-purpose polystyrene and poly(methyl methacrylate) were melt blended in a special mixer–extruder over the complete range of compositions from 100% polystyrene to 100% poly(methyl methacrylate). The blends were characterized for their melt rheological characteristics in a melt elasticity tester which…
Dose-rate Conversion Factors for External Exposure to Photon and Electron Radiation From Radionuclides Occurring in Routine Releases From Nuclear Fuel Cycle Facilities
Dose-rate conversion factors for external exposure to photon and electron radiation are calculated for 240 radionuclides of potential importance in routine releases from nuclear fuel cycle facilities. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a c…
The enzymes of the galactose cluster in Saccharomyces cerevisiae. II. Purification and characterization of uridine diphosphoglucose 4-epimerase.
Uridine diphosphoglucose 4-epimerase (EC 5.1.3.2) of Saccharomyces cerevisiae was purified to homogeneity with a yield of 30%. The purification procedure involved ammonium sulfate precipitation, streptomycin treatment, chromatography on diethylaminoethyl cellulose and hydroxylapatite, and Bio-Gel A-0.5m gel filtration…
Paramagnetic centres associated with bonding defects in v-SiO2
Paramagnetic centres are produced in vitreous (v)-SiO2 by the trapping of photogenerated electrons and holes at the intrinsic bonding defect centres associated with over- and under-coordinated oxygen atoms, C3 + and C1- respectively. Capture of a hole by the C1- converts that centre to C1 0, the oxygen hole centre (OH…
Crystallinity of bulk polyacetylene
Abstract The fine structure of bulk trans ‐polyacetylene (PA) was investigated by x‐ray diffraction. The degree of crystallinity 0.81, determined by Ruland's method, was significantly higher than the value for linear polyethylene. The disorder parameter k was 5, which is much larger than the value for polyethylene. Th…
Influence of substituted pyridines on the redox reactions of iron porphyrins
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInfluence of substituted pyridines on the redox reactions of iron porphyrinsK. M. Kadish and L. A. BottomleyCite this: Inorg. Chem. 1980, 19, 4, 832–836Publication Date (Print):April 1, 1980Publication History Published online1 May 2002Published inissue 1 April 1980https://d…
Mechanism of the catalytic hydrogen production by gold sols. Hydrogen/deuterium isotope effect studies
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMechanism of the catalytic hydrogen production by gold sols. Hydrogen/deuterium isotope effect studiesKenneth Kopple, Dan Meyerstein, and Dan MeiselCite this: J. Phys. Chem. 1980, 84, 8, 870–875Publication Date (Print):April 1, 1980Publication History Published online1 May 2…
Magnetic characteristics of Laves phase compound PrFe2
The magnetic properties of Laves phase compound PrFe 2 , synthesised at high pressure, were studied by Mossbauer spectroscopy and saturation magnetisation. The ferromagnetism in PrFe 2 has been confirmed. The rotation of the easy axis of magnetisation on the (110) plane to (111) with respect to (001) was observed as t…
Mesomorphic Transition Metal Complexes. 4. Dithiene Complexes of Ni, Pd, and Pt.
A rational synthesis of transition metal dithiene complexes with mesophorphic properties is reported. In addition to the nickel complexes described earlier, we have now obtained the Pd and Pt congerers. While the Ni and Pt complexes show, depending on the length of the para-n-alkyl chains, smectic or nematic mesophase…
Wool wax hydrocarbons: A review
Abstract A review of the literature on wool wax hydrocarbons reveals that the hydrocarbons represent about 0.5% of wool wax and that they consist of a large number of normal and branched homologs. This, in turn, shows a structural similarity between the hydrocarbons and the wool wax acids or wool wax aliphatic alcohol…
Experimental studies of a consecutive—competitive reaction in steady state and forced periodic CSTRs
Abstract Experimental studies of diethyl adipate saponification in a CSTR show that forced cycling of feed composition produces significant yield increases in intermediate product relative to the optimal steady state operation, while forced temperature cycling has much less effect. Related experiments provide useful t…
Neuartige Selenoantimonat(III)-Anionen in Ba4Sb4Se11
Drei unterschiedliche, isolierte anionische SbSe-Gruppen - die ersten Selenoantimonat(III)-Ionen überhaupt - sind in Ba4Sb4Se11 enthalten. Die formale Verknüpfung von Pyramiden zu zweikernigen Gebilden war bei SbIII-Verbindungen bisher nicht bekannt. (Graue Kreise: Sb, weiße Kreise: Se.)
Hyperfine Fields at Nonmagnetic Atoms on Various Sites in Ferromagnetic Heusler Alloys
Abstract The hyperfine fields at Fe and Sn, as determined by Mössbauer effect and NMR, in a new Heusler alloy Ru 2 FeSn, are reported. By comparison with corresponding data in rhodium based Heusler alloys, it is inferred that a preferential R–Sn (R = Ru or Rh) disorder exists in these alloys. The hyperfine field data…