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991.
In the present paper we introduce a new family of linear positive operators and study some direct and inverse results in simultaneous approximation.  相似文献   
992.
993.
The conditions of compatibility of the magnetic sublattice hypothesis with the requirements of quantum theory have been derived. These conditions imply the presence of (even weak) magnetic anisotropy and a macroscopic number of spins in the sublattice.  相似文献   
994.
995.
Jeong  M. T. 《Hyperfine Interactions》2004,156(1-4):165-168
Hyperfine Interactions - The decay constants of nuclei are calculated based on the Cheon's idea, namely, the population of nuclear excited state can be modified by the mechanism that the...  相似文献   
996.
Zboril  R.  Mashlan  M.  Machala  L.  Walla  J.  Barcova  K.  Martinec  P. 《Hyperfine Interactions》2004,156(1-4):403-410
Hyperfine Interactions - The natural garnets from almandine (Fe3Al2Si3O12)–pyrope (Mg3Al2Si3O12) series with the iron to magnesium atomic ratio ranging from 0.2 to 1 were characterised and...  相似文献   
997.
A number of phenomena connected with the formation of electrode jets in discharges in hydrogen at a current of 10/sup 5/-10/sup 6/ A, a current growth rate of 10/sup 10/ A/s, an initial pressure 0.1-4.0 MPa, and a discharge gap length of 5-40 mm were studied. After the secondary breakdown, the jets are observed through a discharge semitransparent channel, widening with velocity (4-7) /spl middot/ 10/sup 2/ m/s. Shockwave formation was detected at the interaction of jets with the surrounding gas and the opposite electrode. Plasma vapor pressure of metal near the end of the tungsten cathode 70 /spl mu/s after initiation of a discharge was 180 MPa. Thus, magnitude of brightness temperature was 59 /spl middot/ 10/sup 3/ K, with an average charge of ions-m~=3.1, and a concentration of metal vapors n=5.3/spl middot/10/sup 19/ cm/sup -3/. While those at the end of the anode 90 /spl mu/s after initiation of discharge: m~=2.6, n=7.4/spl middot/10/sup 19/ cm/sup -3/. Probable reasons of high-voltage drops near the electrodes (the summarized magnitude of which is /spl sim/1 kV) are discussed on the basis of experimental data. For the first time, the shadow method registered symmetric ejection of material from the all-cathode surface the maximum discharge current was observed.  相似文献   
998.
999.
For any two points p and q in the Euclidean plane, define LUNpq = { v | vR2, dpv < dpq and dqv < dpq}, where duv is the Euclidean distance between two points u and v . Given a set of points V in the plane, let LUNpq(V) = V ∩ LUNpq. Toussaint defined the relative neighborhood graph of V, denoted by RNG(V) or simply RNG, to be the undirected graph with vertices V such that for each pair p,qV, (p,q) is an edge of RNG(V) if and only if LUNpq (V) = ?. The relative neighborhood graph has several applications in pattern recognition that have been studied by Toussaint. We shall generalize the idea of RNG to define the k-relative neighborhood graph of V, denoted by kRNG(V) or simply kRNG, to be the undirected graph with vertices V such that for each pair p,qV, (p,q) is an edge of kRNG(V) if and only if | LUNpq(V) | < k, for some fixed positive number k. It can be shown that the number of edges of a kRNG is less than O(kn). Also, a kRNG can be constructed in O(kn2) time. Let Ec = {epq| pV and qV}. Then Gc = (V,Ec) is a complete graph. For any subset F of Ec, define the maximum distance of F as maxepqFdpq. A Euclidean bottleneck Hamiltonian cycle is a Hamiltonian cycle in graph Gc whose maximum distance is the minimum among all Hamiltonian cycles in graph Gc. We shall prove that there exists a Euclidean bottleneck Hamiltonian cycle which is a subgraph of 20RNG(V). Hence, 20RNGs are Hamiltonian.  相似文献   
1000.
Avian myosin light-chain kinase from smooth muscle of the gizzard and its catalytic domain, derived from the intact enzyme by trypsin digestion, was purified within 30-40 min by both analytical and preparative anion-exchange high-performance liquid chromatography. The proteins obtained were more than 95% pure and retained their biological activity. The high-performance anion-exchange chromatography protocols represent a significant decrease in purification time when compared with conventional ion-exchange chromatography.  相似文献   
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