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991.
The theorem relating the bisectors of the edges of a triangle and the corresponding circumscribing circle is established as a special case of a theorem for triangles with weighted vertices where the edges are partitioned with circular arcs in the proportions of the weights. The circular arcs are established as being uniquely determined by the weights and the triangle, and are given by three circles with collinear centres. These circles either intersect in zero, one or two real points, these latter points being the triple points. 相似文献
992.
In the presence of low‐molecular‐weight organic acids, such as formic, acetic, and propionic, inorganic nickel salts in aqueous solutions are converted to the volatile tetracarbonyl by UV irradiation. Experiments were performed using a flow‐through photoreactor, consisting of a 6 m length polytetrafluoroethylene tubing wrapped around a low‐pressure mercury vapor UV lamp (254 nm, 15 W). The efficiency of transformation was estimated to be 95%. As no carbon monoxide or external reductant is required, photochemical synthesis may prove to be useful in material chemistry and applicable to the extractive metallurgy of nickel, as well as its refining and recycling. Copyright © 2004 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. 相似文献
993.
P. Dawson G. Duggan H.I. Ralph K. Woodbridge G.W. t Hooft 《Superlattices and Microstructures》1985,1(3):231-235
We have combined measured 5K excitonic absorption peaks with calculations of the confined particle states to determine the band offsets in GaAs(AlGa)As quantum well heterostructures. Our observations are best fitted with a conduction band-valence band split of about 75:25. This contrasts with the currently accepted value of 85:15 and the recently proposed value of 60:40. 相似文献
994.
995.
Ralph McKenzie 《Algebra Universalis》1991,28(4):589-603
We prove that in a locally finite variety with the congruence extension property, locally solvable congruences are central and locally solvable algebras are Hamiltonian. Also, we prove that a maximal subuniverse of a finite algebra in an Abelian variety is identical with an equivalence class of some congruence.Presented by H. P. Gumm. 相似文献
996.
Merrick R. Mahoney Martin W. Howard Ralph P. Cooney 《Journal of Electroanalytical Chemistry》1984,161(1):163-167
Weak Raman spectra of carbon monoxide on silver electrode surfaces exhibit frequency and intensity variations with changing potential. The frequency-potential dependence is rationalized in terms of electron-transfer to the antibonding π* state of electrosorbed CO. 相似文献
997.
Ralph Howard 《Journal d'Analyse Mathématique》1986,47(1):243-253
LetE
n
be a completen-dimensional Riemannian manifold and letM
p
andN
n−p−1
be compact oriented submanifolds ofE
n
whcih are linked inE
n
. The problem (generalizing one due to Gehring whenE
n
is Euclidean) of finding sharp lower bounds on the volume ofM
p
in terms of a lower bound on the distance ofM
p
fromN is solved in (among other cases) the case whereE
n
orM
p
is simply connected andE
n
is a space form or has a nonpositive upper bound on its sectional curvatures. The main technical tool is a generalization
of an isoperimetric inequality of Bombieri and Simon which they used to solve Gehring's problem.
Research supported in part by a Grant from the University of South Carolina. 相似文献
998.
Ralph Henstock 《Aequationes Mathematicae》1973,9(1):1-18
Many theorems of integration theory are true for a wide range of definitions of integrals. One such theorem is that giving integration by parts, and we discuss it in this paper. 相似文献
999.
1000.