Using Si/Al ratios in suspended matter and sediments as an indicator of diatom productivity changes
(1996). Using Si/Al ratios in suspended matter and sediments as an indicator of diatom productivity changes. GFF: Vol. 118, No. sup004, pp. 89-90.
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High strain rate superplasticity in the fine-grained duplex stainless steel Fe-22Cr-5Ni-3Mo-0.3N
The fine-grained duplex stainless steel Fe-22Cr-5Ni-3Mo-0.3N consisting of α- and γ-Fe(Cr,Ni,Mo) solid solutions exhibits structural superplasticity at deformation temperatures of 900 to 1050°C. The equiaxed microstructure with an average grain size of dα,γ ≈ 3 μm was produced by thermomechanical processing. This stee…
Novel ferroelectric liquid crystals and dopants for induced ferroelectric phases containing 3,4-epoxy-2-octanols as chiral unit
The synthesis of a new class of chiral smectic liquid crystals is described, along with transition temperatures, phase behaviour, spontaneous polarizations and related data. The general structure is shown in A. possessing a chiral unit derived from 3,4-epoxy-2-octanol. Two of these new compounds show seemingly antifer…
Perfect blazing for transmission gratings: generalization and numerical verification
A preceding paper [ J. Opt. Soc. Am. A7, 1736 ( 1990)] demonstrated an interesting property of perfect blazing in transmission for triangular-groove dielectric gratings. The grating was obtained by evaporating an infinitely thin layer of perfectly conducting metal on the small facet of the groove. If an antireflection…
Electron Affinity and Surface Re-ordering of Homoepitaxial Diamond (100)
The change in electron affinity and the re-ordering of the diamond surface upon annealing of a homoepitaxially grown diamond (100) thin film were investigated by ultraviolet photoemission spectroscopy, low energy electron diffraction (LEED), and Auger electron spectroscopy. When the sample was heated to ∼1250° C, the…
Study of the First Row Transition Metals by X-ray Photoelectron Spectroscopy
XPS spectra have been obtained from six metals in the first row of transition elements using a Kratos AXIS HS x-ray photoelectron spectrometer. The six metals analyzed include Cu, Ni, Zn, V, Ge, and Fe. Each sample was Ar+ ion etched before XPS analysis to remove the majority of C and O contamination. The spectra incl…
A demonstration of crystal-field effects in octahedral complexes
A discussion of crystal field theory is usually included in general chemistry texts. This is likely to be one of only two places in the text - the other is the description of the hydrogen atom - where the important concept of light absorption by atoms and molecules is presented. The simple demonstration described here…
Investigation of ferroelectric domains and structural twins in barium titanate crystal
The Ferroelectric domain patterns and the {111} twin boundaries are frequently observed in the BaTiO3 ceramics. The ferroelectric domain structures in BaTiO3 single crystal were investigated by a conventional and a synchrotron white beam X-ray topographies. The domain structure of {111} twinned crystal sample was also…
CrIII‐Phthalocyaninate: Darstellung, Eigenschaften und Kristallstruktur von l‐Bis(triphenylphosphin)iminium‐trans‐di(nitrito(O))phthalocyaninato(2–)‐chromat(III)
Abstract [Cr(H 2 O) 2 Pc 2− ]I x reagiert in Dimethylformamid mit überschüssigem (PNP)NO 2 zu wenig löslichem, grünschwarzem l ‐Bis(triphenylphosphin)iminium‐ trans ‐di(nitrito( O ))phthalocyaninato(2–)chromat(III), l (PNP) trans [Cr( O NO) 2 Pc 2− ], welches triklin in der Raumgruppe P 1 (Nr. 2) mit Z = 2 kristallisi…
On the mechanisms of alumina dissolution with relevance to point feeding aluminum cells
The dissolution of alumina in cryolite melts was studied in a laboratory apparatus intended to simulate the conditions in industrial cells with point feeding. Rapid dissolution is achieved if (1) a large proportion of the batch of alumina added is dispersed in the bath upon addition, and (2) the agglomerates which for…
Effect of graphite shape on the Corrosion of Grey Cast Iron in phosphoric acid
Abstract Grey cast iron (3.4%C–2.7%Si–0.4%Mn–0.5% P–0.008%S) with different morphology of graphite and different amount of ferrite, pearlite and eutectic phases has been subjected to corrosion and electrochemical tests in phosphoric acid solution, simulating the oxidized engine oil. The difference in the cathodic proc…
The Influence of DDT‐Preventing Agents upon the Impact Sensitivity of the polyurethane‐bonded RDX
Abstract The effect of some DDT‐preventing agents (DPAs) and their mixtures on the impact sensitivity of RDX/PU has been studied. All specimen for drop‐hammer test were prepared by solvent‐slurry method. Two ways were used in adding DPA. The behavior of moulding powders obtained to the mechanical impact were assessed…
New phase transitions in the solid solution system (Ca1−xSrx)8[Al12O24](WO4)2
Abstract The intermediate part of the cation substitution series (Ca 1− x Sr x ) 8 [Al 12 O 24 ](WO 4 ) 2 of the aluminate sodalites Ca 8 [Al 12 O 24 ](WO 4 ) 2 and Sr 8 [Al 12 O 24 ](WO 4 ) 2 has been studied as a function of temperature and composition, with emphasis on the range 0.50 ≤ x ≤ 0.60. A composition-induc…
Boron-Nitride–Coated Nuclear Fuels
Pure urania- and urania-gadolinia-containing fuel pellets were coated with boron nitride (BN) to improve the physical and neutronic properties of the fuel. The BN coating seems to have a technological advantage over zirconium-diboride coating. The BN is chemically inert, corrosion resistant, withstands rapid temperatu…
Eocene to Pleistocene Clay Mineral Sedimentation off New Jersey, Western North Atlantic (Sites 903 and 905)
The clay fraction of sediments drilled at Sites 903 and 905 is composed of variable proportions of chlorite, illite, random mixed layers (including illite-smectite and illite-vermiculite), smectite, and kaolinite. The coincidence of major changes in clay mineralogy with increasing values of oxygen isotopes suggests a…
The crystal structure of carminite: refinement and bond valence calculations
Abstract The crystal structure of carminite, PbFe 2 (AsO 4 ) 2 (OH) 2 has been refined. The mineral is orthorhombic, Cccm with a = 16.591(2), b = 7.580(1), c = 12.285(1) Å, Z = 8; the structure has been refined to a conventional R = 3.3% using 913 observed reflections [I>2σ(I)]. The structure contains stepped chain…
Solid-State Characterization of AG337 (Thymitaq††Thymitaq is a trade name of Agouron Pharmaceuticals, Inc.), a Novel Antitumor Drug
AG337 (Thymitaq) is an antitumor compound synthesized by Agouron Pharmaceuticals, Inc., using protein structure-based drug design. AG337 is a hydrochloride salt with a molecular formula of C14H12N4OS.2HCl. This compound was subjected to thermal analyses, Karl Fischer titrimetry, powder X-ray diffractometry, scanning e…
Copolymerization of 3,3,3‐trifluoro‐1,2‐epoxypropane with N‐phenylmaleimide using organozinc initiators
Abstract Novel copolymers consisting of 3,3,3‐trifluoro‐1,2‐epoxypropane (TFEP) and N ‐phenylmaleimide (PMI) units were prepared by the copolymerization of TFEP with PMI initiated with an organozinc compound. Using [Zn(OCH 3 ) 2 · (C 2 H 5 ZnOCH 3 ) 4 ] as an initiator, the copolymer chains consisted mainly of TFEP‐TF…
Diffractive beamshaping elements at the fabrication limit
We treat the generation of flat-top intensity distributions, as required for laser applications at short wavelengths. To obtain high fill factors and almost arbitrary shapes, arrays of diffractive Fresnel zone plates at the fabrication limit are investigated. The angular power spectrum noise due to the binarization of…
The Significance of High Value of Ignition Retard Control on the Catalyst Lightoff
<div class="htmlview paragraph">Ever stringent emission legislation has called for more advanced measures for petrol engine emission control. The main chanllenge is to largely cut off the engine cold-start emissions. The problem is that the catalytic converter does not operate effectively at temperature below th…