The invention relates to orthorhombic greenish-tinged lead chromate pigments containing lead chromate and lead sulfate in a weight ratio of 91:9 to 100:0, which are distinguished by a very high tinctorial strength in application.
Orthorhombic lead chromate pigments in which the weight ratio of lead chromate to lead sulfate is 94:6 to 98:2 are preferred.
The orthorhombic lead chromate pigments obtained can additionally be treated with agents to improve their texture, for example with long-chain aliphatic alcohols, esters, acids or salts thereof, amines, amides, waxes or resinous substances, such as abietic acid or hydrogenation products, esters or salts thereof, and furthermore with nonionic, anionic or cationic surface-active organic agents.
is found to exhibit extremely unusual features which include pressure independence of the Curie temperature in the orthorhombic phase, a re-entrance of the rhombohedral phase at low temperatures, and a change of the type of the magnetic phase transition from second to first-order at the intersection of the structural and magnetic phase boundaries.
The orthorhombic (2 0 0) and (4 0 5) reflections were chosen to monitor the magnetic and structural phase-transitions, respectively.
When the crystal is compressed in the orthorhombic phase, the Mn-O-Mn angle is 180° by symmetry, and pressure cannot affect it, changing instead the inter-planar distances.
www.ill.fr /AR-97/page/20magnet.htm (1066 words)
Orthorhombic(Site not responding. Last check: 2007-10-14)
Orthorhombiclattices result from stretching a cubiclattice along two of its lattice vectors by two different factors, resulting in a rectangular prism with a rectangular base (''a'' by b, which is different from a) and height (''c'', which is different from a and b).
There are four orthorhombicBravais lattices: simple orthorhombic, base-centered orthorhombic, body-centered orthorhombic, and face-centered orthorhombic.
The simple orthorhombic is made by deforming the square bases of the tetragonal into rectangles, producing an object with mutually perpendicular sides of three unequal lengths.
The base orthorhombic is obtained by adding a lattice point on two opposite sides of one object's face.
And the face-centered orthorhombic is obtrained by adding one lattice point in the center of each of the object's faces.
Topazcrystallizes in the orthorhombic system, usually with a prismatic habit (figs.
It is, however, greatly inferior in hardness, the hardness of topaz being only 8; and it has lower refractivity and dispersive powers: moreover, being an orthorhombicmineral, it possesses double refraction.
From phenacite and from rock-crystal, for which it may be mistaken, it is distinguished by being biaxial and by having a much higher specific gravity.
Well, in the orthorhombic system, we will continue the 90 degree angular relationships between all 3 axes, but will vary the length of each individual axis.
However, we may discover after examining a large number of different orthorhombicminerals that we see a large number of prism forms expressed on a single crystal, and these forms cannot be expressed with unity in their numbers because their intersects upon the horizontal axes are not proportionate to their unit lengths.
A relatively large number of orthorhombicminerals are encountered with combinations of the various forms presented so far.
The natural sulfate of strontium, SrSO 4, it is important as a source of strontium and of certain of its compounds, e.g., strontium hydroxide, used in refining beet sugar, and strontium nitrate,...
It has an orthorhombic system, massive or columnar aggregates, or hexagonal twinned crystals.
It is a white, orthorhombic crystalline compound at ordinary temperatures; above 100°C it assumes a monoclinic structure, and above about 250°C it assumes a hexagonal structure.
Because in the Orthorhombic System each crystallographic axis (the brachy axis (= a axis), macro axis (= b axis) and vertical axis (= c axis) is unique, each of the three corresponding mirror planes perpendicular to one of the axes (in the holohedric Forms) can be considered as unique.
As has been said, the 2-fold rotation axis perpendicular to this (now suppressed) mirror plane will be considered to be coincident with the crystallographic c axis which is (by convention) placed vertically.
We will now derive those same Forms by subjecting the basic faces (compatible with the OrthorhombicCrystal System) one by one to the symmetry operations of the present Class (the Rhombic-pyramidal Crystal Class).
In crystals of the orthorhombic system the faces consist of two pairs of different isoceles triangles; the crystal is then termed a rhombic tetrahedron.
In der Kristallographie ist das orthorhombic Kristallsystem eine der 7 Gitterpunktgruppen.
Orthorhombic vergittert Resultat vom Ausdehnen eines Kubikgitters entlang zwei seiner Gittervektoren durch zwei unterschiedliche Faktoren, mit dem Ergebnis eines rechteckigen Prismas mit einer rechteckigen Unterseite (a durch b, das zu a unterschiedlich ist) und Höhe (c, das zu a und b unterschiedlich ist).
Es gibt vier orthorhombic Bravais-Gitter: einfaches orthorhombic, Unterseite-zentriertes orthorhombic, raumzentriertes orthorhombic und flächenzentriertes orthorhombic.
Using a dispersion relation derived under the acoustic medium assumption for P-waves in orthorhombic anisotropic media, I obtain an acoustic wave equation valid under the same assumption.
Although this assumption is physically impossible for anisotropic media, it results in wave equations that are kinematically and dynamically accurate for elastic media.
The orthorhombic acoustic wave equation, unlike the transversely isotropic (TI) one, is a six-order equation with three sets of complex conjugate solutions.
The cubic to orthorhombic transition is described by three parameters: three stretches along three mutually perpendicular directions.
The homogeneous deformation that takes a cubiclattice into an orthorhombiclattice has gradient denoted as U which is called a transformation stretch matrix, and for the cubic-to-orthorhombic transition, there are two kinds of such matrices [1].
The transformation stretch matrices are the gradient of the deformations which take a cubiclattice into an orthorhombiclattice.
Definition of Orthorhombic(Site not responding. Last check: 2007-10-14)
Orthorhombiclattices result from stretching a cubiclattice along two of its lattice vectors by two different factors, resulting in a rectangular prism with a rectangular base (a by b, which is different from a) and height (c, which is different from a and b).
There are four orthorhombicBravais lattices: simple orthorhombic, base-centered orthorhombic, body-centered orthorhombic, and face-centered orthorhombic.
Titanium matrix composites (TMC's) are commonly made up of a titanium alloy matrix reinforced by silicon carbide fibers that are oriented parallel to the loading axis.
Orthorhombictitanium aluminide alloys are of particular interest for such TMC applications because their tensile and creep strengths are high in comparison to those of other titanium alloys (ref. 2).
The objective of this investigation was to assess, in simulated mission tests at the NASA Lewis Research Center, the durability of a SiC(SCS-6)/Ti-22Al-23Nb (at.%) TMC for compressor ring applications, in cooperation with the Allison Engine Company.
One uses to orient the orthorhombic axial system such that one axis is vertical which is then called the c axis.
The system of orthorhombic crystallographic axes and its orientation to the beholder is shown in Figure 1, while the equatorial plane of this axial system is shown in Figure 2.
In the orthorhombicCrystal Class denoted by the Hermann-Mauguin symbol m m 2, for example, the brachy axis is at right angles to a mirror (m), the macro axis is at right angles to a mirror (m), and the vertical axis is a 2-fold rotation axis (2).
The orthorhombic system is based on three unequal axes all at right angles to each other.
The model type crystal is called a disphenoid and is similar to the tetragonal disphenoid of the 22nd and the 24th classes and the tetrahedron of the 31st class.
The orthorhombic disphenoid has scalene triangular faces as opposed to the isosceles triangles of the tetragonal disphenoid and the equalateral triangles of the isometric tetrahedron.
Axial Ratios, Parameters, Miller Indices(Site not responding. Last check: 2007-10-14)
So, for example, in 1896 the axial ratios of orthorhombicsulfur were determined to be nearly exactly the same as those reported above from x-ray measurements.
For example, in the orthorhombiccrystal shown here, the large dark shaded face is the largest face that cuts all three axes.
To refer to a general face that intersects all three crystallographic axes where the parameters are not known, we use the notation (hkl).
The crystals belong to the orthorhombic space group P2(1)2(1)2(1) and have unit cell dimensions of a = 86.0 A, b = 40.9 A, and c = 53.3 A (1 A = 0.1 nm).
A second orthorhombiccrystal form (P2(1)2(1)2(1) with cell dimensions differing from the first form) and a trigonal (P3(1)21) crystal form were also characterized.
The structures of the first orthorhombic and the trigonal form were determined by seleno-methionine multiwavelength anomalous dispersion, and the structure of the second orthorhombic form was determined by molecular replacement using the structure from the trigonal form as a search model.
"MR34A-02" in fm06(Site not responding. Last check: 2007-10-14)
Orthorhombic perovskites are a major lower mantle constituent whose properties are well studied and still controversial.
While end member properties have been most studied, the effects of the addition of other elements such as iron and aluminum are less known.
We have undertaken the study of several orthorhombic perovskites in order to develop a sensible thermodynamic model.
www.agu.org /cgi-bin/wais?hh=MR34A-02 (251 words)
Batteries with Orthorhombic Sodium Manganese Oxide Cathodes(Site not responding. Last check: 2007-10-14)
This material is based on an orthorhombicsodium manganese oxide, and has a capacity of approximately 160 mAh/g in sodium batteries in a voltage range compatible with polymer electrodes (3.4-2.2 V vs. Na).
Berkeley National Laboratory scientists can readily oxidize, reduce or use mild chemical routes to exchange the orthorhombicsodium manganese oxide to form a material suitable for use in lithium rechargeable cells.
The lithiated form of the orthorhombicsodium manganese oxide maintains its structural integrity upon deep discharge and prolonged cycling in lithium cells.
Spartanburg SC | GoUpstate.com | Spartanburg Herald-Journal(Site not responding. Last check: 2007-10-14)
The pyroxenes are a group of important rock-forming silicate minerals found in many igneous and metamorphic rocks.
They share a common structure comprised of single chains of silica tetrahedra and they crystalise in the monoclinic and orthorhombic system.
There is not complete solid solution in calcum content and Mg-Fe-Ca pyroxenes with calcium contents between about 15 and 25 mol.% are not stable with respect to a pair of exolved crystals.
C upfield compared to the line in the orthorhombic phase.
C chemical shift has revealed that 7% gauche defects are included in the hexagonal phase.
jump rotation around the molecular chain axis is induced in the orthorhombic phase at temperatures near the orthorhombic-to-hexagonal phase transition.