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Abstract  

We show that every 4-dimensional anti-Khler manifold is Einstein and locally symmetric. In particular any 4-dimensional anti-Khler manifold with zero scalar curvature is flat.

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Abstract  

The different approaches of the monostandard activation analysis are evaluated critically in order to put them into a common formulation. The nuclear data relevant to the method, which are selected and verified by experiment, are presented for general application. The accuracy of the method for multielement analysis is discussed by comparing the analytical results of the various reference materials from different methods and laboratories with those from monostandard activation analysis.

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Abstract  

We show that in dimension 8, a semiflat metric is flat and that in dimension (8k+4) higher than 8, a semiflat metric does not necessarily imply flat.

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Abstract  

The novel N4S2 azacrown ion exchange resin was prepared. The ion exchange capacity of N4S2 ion exchanger was 0.34 meq/g dry resin. A study on the separation of lithium isotopes was carried out with N4S2 azacrown ion exchange resin. The lighter isotope,6Li is concentrated in the resin phase, while the heavier isotope,7Li is enriched in the solution phase. With column chromatography [0.1 cm (I.D.)×32 cm (height)] using 2.0M NH4Cl as an eluent, separation factor, a=1.034 was obtained.

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Abstract  

The novel NDOE (1,12,15-triaza-3,4:9,10-dibenzo-5,8-dioxacycloheptadecane) ion exchange resin was prepared. The ion exchange capacity of NDOE azacrown ion exchanger was 0.2 meq/g dry resin. A study on the separation of lithium isotopes was carried out with NDOE novel azacrown ion exchange resin. The lighter isotope,6Li concentrated in the solution phase, while the heavier isotope,7Li is enriched in the resin phase. By column chromatography (0.1 cm I.D.×32 cm height) using 2.0M NH4Cl as an eluent, a separation factor,a=1.0201 was obtained.

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Abstract  

The average fission neutron cross-sections of the reactions233U(n, 2n)232U,60Ni(n, p)60Co and27Al(n, p)27Mg and the resonance integrals of the (n, γ)-reactions of the nuclides181Ta,176Lu,175Lu,64Ni,59Co and26Mg have been determined by the activation method following the well-known conventions. The results verify some of the existing values and present data for hitherto unknown or poorly known reactions.

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Abstract  

At the treatment of HLLW (high-level liquid radioactive waste) by oxalate precipitation, the filtrate is occured as a waste. But various elements including Cs and Sr are contained in the oxalate filtrate. It is very important, therefore, to separate from each other in a viewpoint of ultimate isolation of heat generating nuclides such as Cs and Sr from HLLW. In this study, the simulated oxalate filtrate, consisted of five elements (Cs, Sr, Ru, Fe and Mo) and organics (oxalic acid and ascorbic acid), was prepared, from which the separation of Cs and Sr was carried out by neutralization with NaOH. As a result, the simulated solution could be divided into Cs, Sr and Ru containing groups with pH. Sr was readily precipitated as forms of Sr(C2O4nH2O at pH 3. Iron and ruthenium were also co-precipitated around pH 8, and Cs and Mo remained in the resulting solution.

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Abstract  

We prove a reduction theorem of codimension for real submanifolds of quaternionic hyperbolic spaces as a quaternionic analogue corresponding to those in Cecil [2], Erbacher [4], Kawamoto [8], Kwon and the second author [10] and Okumura [13].

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Abstract  

Let M be the closed, simply connected, 4-manifold with nonnegative sectional curvature, called a nonnegatively curved 4-manifold, with an effective and isometric Z m-action for a positive integer m ≧ 617. Assume that Z m acts trivially on the homology of M. The goal of this short paper is to prove that if the fixed point set of any nontrivial element of Z m has at most one two-dimensional component, then M is homeomorphic to S 4, #i l=1S 2 × S 2, l = 1, 2, or #j k = 1 ± CP 2, k = 1, 2, 3, 4, 5. The main strategy of this paper is to give an upper bound of the Euler characteristic χ(M) under the homological assumption of a Z m-action as above by using the Lefschetz fixed point formula.

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Abstract  

An edited transcript of the plenary discussion is given on the subject of “Representative Sampling and the Proper Use of Reference Materials” which was held at the International Conference: Modern Trends in Activation Analysis on September, 15, 1976 in Munich, Federal Republic of Germany.

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