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。
Abstract The structure of a selection of arsenate‐and sulphate‐based minerals of the tsumcorite group was studied by the combination of Raman and infrared spectroscopy. A comparison is made with the sulphate‐bearing mineral natrochalcite. Isomorphic substitution of sulphate for arsenate is observed for gartrellite and…
Crystals of δ‐Y 2 Si 2 O 7 (space group P 12 1 / c 1) were examined using high‐temperature powder X‐ray diffractometry to determine their unit‐cell dimensions from 296 to 1473 K. The lattice deformation induced by thermal expansion was investigated using matrix algebra analysis to determine the directions and magnitud…
The present study compares castability and mechanical performance among alloys of c.p. Ti, Ti-6Al-7Nb and a newly-developed Ti-15Mo-1Bi in regard to their as-cast state. Experimental results indicate that average cast length of Ti-6Al-7Nb appears a little lower than c.p. Ti and Ti-15Mo-1Bi, although the differences ar…
A new genus, Talaroneis Kooistra & De Stefano, gen. nov. and a new species T. posidoniae Kooistra & De Stefano, sp. nov. are described. The elongate cells, which were found on a leaf of Posidonia oceanica, formed star-, zigzag- or ribbon-shaped colonies in culture. The distinctive character of T. posidoniae was the pr…
Chemical (electroless) deposition of silver oxysalts such as Ag 7 NO 11 × 3 Ag 2 SO 4 and Ag 7 NO 11 as powders or on a textile, i.e. , high density polyethylene is investigated. The process is based on a reaction between AgNO 3 , a source of Ag(I) ion, and ( NH 4 ) 2 S 2 O 8 or K 2 S 2 O 8 used as oxidizing agents of…
A range of novel starch based graft composites with synthetic polymers were prepared. These exhibit high surface areas as well as excellent thermal stabilities and useful wetting properties.
Remarkable room-temperature liquid crystallinity is observed for a wide range of metal soaps. Incorporation of saturated, mid-chain mono-methyl branched C17 fatty acid (mid-chain branched fatty acid) into metal soaps lowers the liquid crystalline transition to below room temperature. Soaps of Na, Mg, Al, Ca, Cu, Zn, S…
Lyotropic nematic textures are investigated, by image processing, near the reentrant isotropic (IRE)–discotic nematic (ND)–biaxial nematic (NB)–clamitic nematic (NC)–isotropic (I) phase transitions in a lyotropic mixture of potassium laurate, decanol, and D2O. The (NB), intermediate phase between the two uniaxial nema…
The thermolysis reaction of a dual precursor system, comprising one that promotes a controlled nucleation event to produce a rod-shaped nanocrystal template, and the other introduced through a subsequent series of injections that maintain the reaction under kinetic drive, is shown to provide a means of controlling gro…
Two complexes of divalent samarium have been synthesized by electrochemical reduction in methanol-tetrahydrofuran solutions: [Sm(18-crown-6)(ClO4)2] and [Sm(15-crown-5)2](ClO4)2. In [Sm(18-crown-6)(ClO4)2] the metal cation is ten-coordinate and its coordination sphere comprises six oxygen atoms of the crown ligand and…
Ia3d cubic mesoporous silica with unusual thermal stability has been synthesized using cetyltrimethylammonium bromide (CTAB) and sugar surfactant dodecyl-beta-D-maltoside (DM) as co-templates.
Advance in understanding glass transition dynamics is made by identifying (1) the “universal” Johari‐Goldstein (JG) relaxation with the primitive relaxation of the coupling model and (2) the nearly constant loss (NCL) as the short time caged dynamics, all with support from experimental data. Dynamics proceeds with tim…
This paper summarizes 2-1/2 decades of full-scale aircraft and rotorcraft crash testing performed at the Impact Dynamics Research Facility (IDRF) located at NASA Langley Research Center in Hampton, Virginia. The IDRF is a 240-ft.-high steel gantry that was built originally as a lunar landing simulator facility in the…
The oxygen storage capacity (OSC) of a ceria-zirconia(CeO2-ZrO2) solid solution containing 50 mol% ZrO2 is approximately 400 μmol-O2/g, which corresponds to approximately 50% of the theoretical OSC limit calculated from the valence change of the Ce ion. There are two possible explanations for the OSC suppression of ap…
Riboflavin, an essential cofactor for all organisms, is biosynthesized in plants, fungi and microorganisms. The penultimate step in the pathway is catalyzed by the enzyme lumazine synthase. One of the most distinctive characteristics of this enzyme is that it is found in different species in two different quaternary s…
We report studies of ordered microporous and nanoporous polymer films formed by the evaporation of polymer solutions following exposure to a humid atmosphere. High speed microphotographic (HSMP) studies of the formation process showed that near the surface of the polymer solution, vapour condensation produced near mon…
Abstract The effects of anisotropy of the photoionization cross‐section and elastic scattering of photoelectrons in solids are investigated for angle‐resolved XPS spectra (ARXPS) recorded from α–Al 2 O 3 substrate in parallel data acquisition mode. It is shown that for quantitative analysis of ARXPS spectra recorded i…
Pt and Rh nanoparticles obtained by epitaxial growth on NaCl (001) were coated with a crystalline ceria support and subjected to systematic hydrogen reduction in the temperature range 573 K ≤ T ≤ 973 K. The structural and morphological changes were examined by high resolution electron microscopy and selected area elec…
The FTIR spectra of 4-aminoquinaldine and 5-aminoquinoline were recorded in solid phase on a Bruker IFS 66V spectrometer in the region 4000--400 cm-1. The FT-Raman spectra of these compounds were also recorded in the same instrument with a FRA 106 Raman module. The molecules under investigation are considered to have…
Five novel Gd(iii) complexes based on the structure of the heptadentate macrocyclic 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) ligand have been synthesized and their (1)H and (17)O NMR relaxometric properties investigated in detail. The complexes have been functionalised on the secondary nitrogen atom…