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71.
Michelle Sternberg Jörg Rust Christian W. Lehmann Fabian Mohr 《Helvetica chimica acta》2013,96(2):280-288
Two glucose‐derived thiourea derivatives, 2a and 2b , were prepared by addition of the corresponding amino sugars to a solution of 4‐nitrobenzoyl isothiocyanate (Scheme 1). The thioureas were isolated as colorless solids in good yields and were fully characterized by NMR spectroscopy, optical rotation, elemental analysis, and also by single‐crystal X‐ray diffraction. Attempts to obtain CuII and NiII bis(chelate) complexes with these thioureas failed. However, the C(1)‐protected thiourea derivative 2a reacted with orthopalladated acetato‐bridged dimers to afford the corresponding monomeric PdII complexes 3 and 4 (Scheme 2). In these compounds, the thiourea coordinates to the metal as monoanionic O,S chelate ligand, which was confirmed by X‐ray crystallography. 相似文献
72.
P. Haupt J. W. Koen W. J. Naudé N. J. A. Rust 《Zeitschrift für Physik A Hadrons and Nuclei》1980,295(2):135-146
Levels up to 3,016 keV in59Co were studied using the59Co (p, p′y) and56Fe (α, py) reactions. Level energies, branching ratios, mean lifetimes and spins were obtained for a number of levels. 相似文献
73.
We consider the linear model Y = Xβ + ε that is obtained by discretizing a system of first-kind integral equations describing a set of physical measurements. The n vector β represents the desired quantities, the m x n matrix X represents the instrument response functions, and the m vector Y contains the measurements actually obtained. These measurements are corrupted by random measuring errors ε drawn from a distribution with zero mean vector and known variance matrix. Solution of first-kind integral equations is an ill-posed problem, so the least squares solution for the above model is a highly unstable function of the measurements, and the classical confidence intervals for the solution are too wide to be useful. The solution can often be stabilized by imposing physically motivated nonnegativity constraints. In a previous article (O'Leary and Rust 1986) we developed a method for computing sets of nonnegatively constrained simultaneous confidence intervals. In this article we briefly review the simultaneous intervals and then show how to compute nonnegativity constrained one-at-a-time confidence intervals. The technique gives valid confidence intervals even for problems with m < n. We demonstrate the methods using both an overdetermined and an underdetermined problem obtained by discretizing an equation of Phillips (Phillips 1962). 相似文献
74.
75.
Molter A Rust J Lehmann CW Deepa G Chiba P Mohr F 《Dalton transactions (Cambridge, England : 2003)》2011,40(38):9810-9820
A series of both mono- and dinuclear gold(I) phosphine complexes containing monoanionic seleno- and thiosemicarbazones as ligands were prepared and fully characterized by spectroscopic methods and, in some cases, by single crystal X-ray diffraction. The in vitro anti-malaria activity of some of these compounds was investigated in chloroquine sensitive strains of Plasmodium falciparum. The IC(50) results show that the sulfur containing compounds exhibit activity similar to that of chloroquine, whilst the selenium derivatives display only moderate anti-malaria activity. 相似文献
76.
DR. E. W. J. Mitchell 《Contemporary Physics》2013,54(3):217-222
The accurate measurement of the thermal conductivity of metals still poses considerable experimental difficulty. The reasons for this, and the main ways in which the problem has been approached, are summarized. A detailed examination of the development in technique and methods of measurement shows that while most of the steady-state methods introduced over 50 years ago are still being improved, the emphasis in the last few years has been on the development of methods which give more rapid results, particularly at high temperatures. 相似文献
77.
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80.
Albert E. Rust Chris P. Tsokos 《Annals of the Institute of Statistical Mathematics》1981,33(1):233-246
Summary The properties of the characteristic function of the fixed-bandwidth kernel estimator of a probability density function are
used to derive estimates of the rate of almost sure convergence of such estimators in a family of Hilbert spaces. The convergence
of these estimators in a reproducing-kernel Hilbert space is used to prove the uniform convergence of variable-bandwidth estimators.
An algorithm employing the fast Fourier transform and heuristic estimates of the optimal bandwidth is presented, and numerical
experiments using four density functions are described.
This research was supported by the United States Air Force, Air Force Office of Scientific Research, Under Grant Number AFOSR-76-2711. 相似文献