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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Tamás Csermely, Georg Petroianu, Kamil Kuca, Józsel Fűrész, Ferenc Darvas, Zsolt Gulyás, Rudolf Laufer, and Huba Kalász

Quaternary pyridinium aldoximes have been analyzed by thin-layer chromatography. Their separation was adequate when silica plates were used with a mobile phase with a high water content. As a consequence of their limited migration, reversed-phase TLC was not appropriate for determination of the lipophilicity of quaternary pyridinium aldoximes. Displacement TLC of some quaternary pyridinium aldoximes is, nevertheless, possible using silica as stationary phase with water-acetone-hydrochloric acid mobile phases. Normal-phase TLC with different concentrations of organic modifier gave a series of R M values for the pyridinium aldoximes. Approximation of the different plots of R M against organic modifier concentration to straight lines afforded R M,0 values and the slopes of the lines. The R M,0 values and the slopes both serve as indicators of the hydrophilic character of the compounds.

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Abstract  

This is a direct continuation of Part II of this series of papers and we shall not only improve (numerically) all our former results in Part II, but also prove new theorems, Theorem 4 on the function f(t) = log Γ(t+λ) and Theorem 5 for k-th power moments, k = 2,...,7, by elaborating our previous arguments.

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Abstract  

Neutron activation analysis has been used for the determination of trace elements in different wines coming from various french vineyards. The technics used are non destructive for short and middle half-life radionuclides (28Al−76As−49Ca−38Cl−42K−27Mg−56Mn−24Na−52V). A radiochemical separation is necessary for longer half-life radionuclides (60Co−52Cr−134Cs−59Fe−86Rb−65Zn). The results of our study show that the identification of vineyards based on the determination of specific oligo-elements can be proposed. However more data are needed to demonstrate that the knowledge of the amounts of specific oligo-elements in a wine corresponding to a given vineyard can be used for disclose frauds more particularly in the cases of wine watering or mixtures of wines coming from different vineyards.

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Abstract  

A mixture of radium-224, lead-212 and barium-133 as well as a mixture of lead-210 and bismuth-210 were used for the investigation of these elements in algae Scenedesmus obliquus in dependence of equilibrium pH in the absence and in the presence of other salts. It has been found that the affinity constant KM decreases in the following order (lg KM values are given in parentheses): Ra2+ (5.1), Ba2+ (4.8), Sr2+ and Ca2+ (4.6), Mg2+ (4.2), Cs+, Rb+ and NH 4 + (2.9), K+ (2.7), Na+ (2.6) and Li+ (2.4). The uptake of lead and bismuth is more complicated because of the accumulation of free cations as well as hydroxo complexes.

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Abstract  

Food samples were irradiated with thermal and epithermal neutrons. The average ratios of thermal to epithermal activity were determined for80Br,49Ca,38Cl,60mCo,42K,27Mg,56Mn,24Na, and86mRB. They were equal to 2.1, 26, 24, 6.6, 19, 16, 11, 23 and 1.9, respectively. Then, 57 food samples were analyzed by epithermal neutron activation analysis for Br and Rb. The concentrations (in ppm) of Br and Rb were in asparagus (2) 2.3, 11.5; beets (3) 0.5, 0.8; beef (3) 1.7, 3.6; cabbage (5) 0.5, 10.8; carrot (3) 0.2, 3.7; chicken (3) 0.6, 4.4; chocolate (7) 11.1, 18.7; egg (3) 0.9, 1.9; french bean (3) 0.3, 1.0; goose (2) 1.3, 9.3; lettuce (2) 0.9, 1.7; pork (1) 1.5, 4.4; potato (7) 1.0, 1.2; sausage (3) 0.6, 4.0; strawberry jam (3) 0.4, 1.4; tomato (1) 13.5, 14.6; turkey (3) 1.2, 4.9. respectively. The number of samples analyzed is indicated in parentheses.

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Let K ⊂ ℝ2 be an o-symmetric convex body, and K* its polar body. Then we have |K| · |K*| ≧ 8, with equality if and only if K is a parallelogram. (|·| denotes volume). If K ⊂ ℝ2 is a convex body, with o ∈ int K, then |K| · |K*| ≧ 27/4, with equality if and only if K is a triangle and o is its centroid. If K ⊂ ℝ2 is a convex body, then we have |K| · |[(KK)/2)]*| ≧ 6, with equality if and only if K is a triangle. These theorems are due to Mahler and Reisner, Mahler and Meyer, and to Eggleston, respectively. We show an analogous theorem: if K has n-fold rotational symmetry about o, then |K| · |K*| ≧ n 2 sin2(π/n), with equality if and only if K is a regular n-gon of centre o. We will also give stability variants of these four inequalities, both for the body, and for the centre of polarity. For this we use the Banach-Mazur distance (from parallelograms, or triangles), or its analogue with similar copies rather than affine transforms (from regular n-gons), respectively. The stability variants are sharp, up to constant factors. We extend the inequality |K| · |K*| ≧ n 2 sin2(π/n) to bodies with o ∈ int K, which contain, and are contained in, two regular n-gons, the vertices of the contained n-gon being incident to the sides of the containing n-gon. Our key lemma is a stability estimate for the area product of two sectors of convex bodies polar to each other. To several of our statements we give several proofs; in particular, we give a new proof for the theorem of Mahler-Reisner.

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1992-ben mészlepedékes csernozjom vályogtalajon beállított szabadföldi kísérletben vizsgáltuk a nitrogén, réz és molibén elemek közötti kölcsönhatásokat tritikáléval. A termőhely talaja a szántott rétegben 3% humuszt, 5% körüli karboná-tot és 20% körüli agyagot tartalmazott. A talajelemzések alapján a terület jó Ca-, Mg-, K- és Mn-, kielégítő Cu-, valamint gyenge-közepes P- és Zn-ellátottságú volt. A talajvíz 13–15 m mélyen található, a terület aszályérzékeny. A tenyészidő kilenc hónapja alatt azonban 379 mm eső hullott, közepes csapadékellátottságot biztosítva a tritikálénak. A kísérletet 4N x 3Cu = 12 kezelés x 3 ismétlés = 36 parcellával állítottuk be osztott parcellás (split-plot) elrendezéssel. A N-trágyázás 0, 100, 200, 300 kg·ha-1, a Cu-trágyázás 0, 50 és 100 kg·ha-1 adagokat jelentett Ca-NH4NO3, illetve CuSO4 formájában. A kísérlet ötödik évében a 15 m hosszú parcellákat megfeleztük és 1 m-es úttal elválasztottuk. A kísérlet így sávos split-plot elrendezésűvé vált 72 parcellával (4N x 3Cu x 2Mo = 24 kezelés x 3 ismétlés). A 48 kg·ha-1 molibdént (NH4)6Mo7O24x4H2O formában alkalmaztuk.

A vizsgálat fontosabb eredményei az alábbiakban foglalhatóak össze.:

Adataink orientálhatják a szaktanácsadást a tervezett tritikále termés elemszük-ségletének számításakor.

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The heat capacity of high-purity indium has been determined by adiabatic-shield calorimetry in the range 300 to 1000 K. Values of thermodynamic functions have been calculated andC p (1000 K), [H° (1000 K)− (298.15 K)], and [S° (1000 K)−S° (298.15 K)] are (27.11±0.15) J K−1 mole−1, (22873±70) J mole−1, and (41.567 ±0.125) J K−1 mole−1, respectively. The enthalpy of fusion is (3283±7) J mole−1 and the melting temperature (429.77±0.01) K. The premelting heat capacity is compatible with the presence of a mole fractionx ≈ 1·10−6 of a liquid-soluble/solidinsoluble impurity in the sample.

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aldoxime groups (K-117, K-269) or an aldoxime and an amide ligand (K-27, K-48, K-127, K-203, K-867, K-868 and K-870). K-269 contains an α-amino methylamide functional group. The crosslink is a non-branched (K-48, K-347, K-868) or branched alkyl (K-27), or

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Hematológia–Transzfuziológia
Authors: Bence Bátai, Dóra Lévai, Júlia Gaál-Weisinger, Alexandra Balogh, Ambrus Gángó, Csaba Bödör, and Noémi Nagy

drive tumor-associated hypertrimethylation of lysine 27 on histone H3 (H3K27) in human B-cell lymphomas. Proc Natl Acad Sci U S A 2010; 107: 20980–20985. 19 Yap DB, Chu J, Berg

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