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121.
Nora Vajda Marta Balla Zsuzsa Molnar Denes Bodizs 《Accreditation and quality assurance》2006,10(11):599-602
The Radiochemical Laboratory participated in the Technical Co-operation (TC) Project on Quality Control and Quality Assurance for Nuclear Analytical Techniques RER/2/004 organized by the International Atomic Energy Agency (IAEA) during the period June 1999 and September 2001. Motivations, major goals of participation in the project, milestones of implementation of the project, establishing the quality system, improvements fulfilling both technical and management requirements as well as major achievements for future activities of the laboratory with respect to technical and financial conditions are discussed in detail. 相似文献
122.
The spectrum problem for minimal blocking sets means
that we wish to determine the possible cardinalities of minimal blocking
sets. Besides surveying the results on this problem some new results (or
new proofs) are given. 相似文献
123.
Gergely B. Cserép Zsuzsa Baranyai Dávid Komáromy Kata Horváti Szilvia Bősze Péter Kele 《Tetrahedron》2014
Fluorescent tagging of Cys-containing peptides is presented herein. The procedure follows a two-step sequential reaction scheme using thiol specific bifunctional chemical reporters and fluorogenic labels. Vinyl-sulfone bearing chemical reporters have been synthesized and demonstrated to selectively modify cysteine under physiological conditions in the presence of other nucleophilic amino acids. Bifunctional chemical reporters decorated with a terminal alkyne moiety, suitable for modification with azide containing fluorogenic labels were also synthesized. Such fluorogenic (turn on) labels in combination with these new vinyl-sulfone tags can be used generally in fluorescent modulation schemes of thiol-bearing biomolecules. 相似文献
124.
A simple one pot phase transfer catalytic method is described for the synthesis of carboxylic amides and esters from carboxylic acids and amines or alcohols, respectively. For the activation of the carboxylic acids “in situ” generated phosphoric acid diester chlorides were applied. 相似文献
125.
Zsuzsa M. Jászay Imre Petneházy László Töke 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Dialkyl phosphoryl chlorides generated “in situ” fiom dialkyl phosphites and CCL on the surface of solid KXO, in the presence of a PT catalyst can be used for activation of carboxylic acids via mixed anhydride formation and also for activation of ureas by the formation of 0-phosphoryl isourea derivatives. In M a reaction of the intermediates result in formation of amides and esters by the reaction of amine or alcohols, or in case of urea the derivative carbodide forming spontaneously by heat 相似文献
126.
The N‐phosphinoylation and N‐phosphorylation reaction of 1‐alkylamino‐2,5‐dihydro‐1H‐phosphole 1‐oxides with diphenylphosphinoyl chloride and diethylphosphoryl chloride/diphenylphosphoryl chloride afforded new families of compounds comprising bis(phosphinoyl)amines and phosphinoyl‐phosphorylamines, respectively, whose stereostructures were elucidated by B3LYP/6‐31G(d,p) and B3LYP/6‐31G++(d,p) calculations. The P analogues of the mixed imides may be valuable intermediates in syntheses. 相似文献
127.
M. Hampele D. Herlach A. Kratzer G. Majer J. Major H. -P. Raich R. Roth C. A. Scott A. Seeger W. Templ M. Blanz S. F. J. Cox K. Fürderer 《Hyperfine Interactions》1991,65(1-4):1081-1087
Resonant transitions between the Zeeman levels of positive muons implanted into α-iron foils have been observed above the
Curie temperature by applying a 17.8 MHz transverse radio-frequency field and varying the longitudinal external field. Resonance
signals of free and trapped muons are detected. 相似文献
128.
In this paper we construct an infinite series of (q + t, t)-arcs of type (0, 2, t). We show that this construction includes the Korchmáros-Mazzocca arcs, and we gain new infinite series of examples, too. 相似文献
129.
D. Herlach G. Majer J. Major J. Rosenkranz M. Schmolz W. Schwarz A. Seeger W. Templ E. H. Brandt U. Essmann K. Fürderer M. Gladisch 《Hyperfine Interactions》1991,63(1-4):41-48
The spin precession of positive muons in ultra-pure Nb single crystals of high perfection, cooled down in transverse magnetic
fields 0.68B
c2≤B
appl≤0.84B
c2 (B
c2=upper critical field) from temperatures well above the superconducting transition temperatureT
c=9.25 K, has been investigated in the temperature range 2.6 K≤T≤8.0 K. The experiments confirm the periodic fieldB(r) of triangular flux-line lattices as calculated from numerical solutions of the microscopic BCS-Gor'kov theory. The observed
broadening of the van Hove singularities in the field distribution is discussed in terms of the combined effects of muon diffusion
and random perturbations of the flux-line lattice. 相似文献
130.
CD data of the optically active 4-hydroxy (1–5) and 4-acetoxy chromans (6–8) were analyzed by two different approaches. The Snatzke-Antus treatment of chiraly perturbed chromane chromophore revealed M absolute conformation and 4S absolute configuration of the alcohols, i.e. P absolute conformation and 4R absolute configuration of the acetates. The proposed absolute configuration of the optically active alcohols was confirmed for 1 and 2 by the chiral excitone coupling method applied on their benzoates 9 and 10. 相似文献