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In this paper we continue to study the spectral norms and their completions ([4]) in the case of the algebraic closure $ \overline {\mathbb Q} $ of ? in ?. Let $ \widetilde{\overline{\mathbb{Q}}} $ be the completion of $ \overline {\mathbb Q} $ relative to the spectral norm. We prove that $ \widetilde{\overline{\mathbb{Q}}} $ can be identified with the R‐subalgebra of all symmetric functions of C(G), where C(G) denotes the ?‐Banach algebra of all continuous functions defined on the absolute Galois group G = Gal$ {\overline {\mathbb Q}} / {\mathbb Q} $. We prove that any compact, closed to conjugation subset of ? is the pseudo‐orbit of a suitable element of $ \widetilde{\overline{\mathbb{Q}}} $. We also prove that the topological closure of any algebraic number field in $ \widetilde{\overline{\mathbb{Q}}} $ is of the form $\widetilde{\mathbb{Q}[x]}$ with x in $ \widetilde{\overline{\mathbb{Q}}} $.  相似文献   
3.
We introduce the notion of n-nuanced MV-algebra by performing a Łukasiewicz–Moisil nuancing construction on top of MV-algebras. These structures extend both MV-algebras and Łukasiewicz–Moisil algebras, thus unifying two important types of structures in the algebra of logic. On a logical level, n-nuanced MV-algebras amalgamate two distinct approaches to many valuedness: that of the infinitely valued Łukasiewicz logic, more related in spirit to the fuzzy approach, and that of Moisil n-nuanced logic, which is more concerned with nuances of truth rather than truth degree. We study n-nuanced MV-algebras mainly from the algebraic and categorical points of view, and also consider some basic model-theoretic aspects. The relationship with a suitable notion of n-nuanced ordered group via an extension of the Γ construction is also analyzed.  相似文献   
4.
Summary A separated filtered ring has a maximally complete immediate extension. This is an analogue of Krull Theorem from valuation ring theory in the frame of filtered rings.
Riassunto Un anello separato filtrato ha una immediata estensione massimale completa. Questo risultato è un analogo del teorema di Krull della teoria degli anelli di valutazione nell’ambito degli anelli filtrati.
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5.
The ambient framed bordism class of the connecting manifold of two consecutive critical points of a Morse-Smale function is estimated by means of a certain Hopf invariant. Applications include new examples of non-smoothable Poincaré duality spaces as well as an extension of the Morse complex.  相似文献   
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This work discusses the synthesis and the fragmentation patterns for 2-(p-acetylaminosulfonamido)-2-thiono-(5,5-dimethyl-1,3,2-dioxaphosphorinane)(1) and for the p-acetylaminosulfonylamides of O,O-diethylthiophosphoric acid (2), O,O-diphenylthiophosphoric acid (3), dimethylaminocyclohexylthiophosphoric acid (4), and diethylaminophenylthiophosphoric acid (5). A thionamidic-thiolimidic structure was attributed to compounds 1-5, consistent with their IR and NMR spectra. EI mass spectra at 70 eV, high resolution (HR) mass measurements and metastable ion spectra were used to elucidate the fragmentation processes and to determine the kinetic energy release values associated with the metastable ion dissociations. HR accurate mass measurements were used to confirm the compositions of the more abundant ions.  相似文献   
9.
In order to find support for the validity of the hypothesis proposed by one of us regarding the different natures of the bonds in the four successive complexes formed between Ag+ and thiourea, the corresponding enthalpies are verified by direct calorimetry.Furthermore, because the influence of substituent groups on the nitrogen atoms may help to characterize the donor atom. the calorimetric enthalpies and potentiometric free energies of complexation between Ag+ and N-methylthiourea, N,N′- dimethylthiourea and N,N′-diethylthiourea have also been determined at 25°C, in aqueous medium of ionic strength μ = 0.5 M KNO3.  相似文献   
10.
Zusammenfassung Es wurden 34 neue Komplexsalze durch doppelte Umsetzung aus wäßr.-alkohol. Lösungen der folgenden Reineckeat-Analoga: [Cr(NCS)4(m-xylidin)2], [Cr(NCS)4(p-xyl)2] und Hexammin-, Monoacido-pentammin- und Diacido-tetramminkobalt(III)-komplexsalze erhalten. Es wurden in einigen Fällen Unterschiede in physiko-chemischen Eigenschaften, wie Farbtönung, Kristallform, Löslichkeit und papierchromatographischeR f-Werte, bei den stellungsisomeren Salzen vom Typus: Kation · [Cr(NCS)4(xyl)2] und auch bei den Koordinationsisomerpaaren: [Co(DH)2(m-xyl)2] [Cr(NCS)4(p-xyl)2] und [Co(DH)2(p-xyl)2] [Cr(NCS)4(m-xyl)2] usw. beobachtet.
Cobalt(III)ammine derivatives of some reineckate analogues with xylidines
34 new complex salts were prepared by double conversion of the reineckate analogues [Cr(NCS)4(m-xylidine)2], [Cr(NCS)4(p-xyl)2], with the hexammine-, monoacido-pentammine- and diacidotetrammine-complexes of Co(III). In some of the position and coordination isomeres differences of the standard physico-chemical properties, i.e. color, crystal form, solubility and paper chromatographyR f-values were observed.
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