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41.
J. Kuriplach L. Lešták M. Rotter B. Sedlák M. Trhlík M. Finger T. Lešner J. Dupák P. Novák M. Vobecký 《Hyperfine Interactions》1987,34(1-4):339-342
First experimental results of160Tb nuclear orientation in yttrium single crystal matrix are described. The influence of external magnetic field in combination with the crystal field interaction is discussed. 相似文献
42.
In the framework of path integrals we present a solution to the Schrödinger equation for a free particle confined to the half-linex > 0. A solution in question corresponds to the boundary condition (/x) (0,t)= (0,t) where is a real constant. 相似文献
43.
44.
J. Brandštetr 《Journal of Thermal Analysis and Calorimetry》1981,21(2):357-365
A review of instruments for thermochemical (thermometric) solution analysis is given, including new types of isoperibol reaction of bomb calorimeters, the design of which can influence the future development of thermochemical measuring techniques. The new type of Dithermanal (Vaskut-EMG, Hungary, and Herrmann- Morris, France) controls the individual steps of the thermochemical analysis, adding memory and computing capabilities. Similar programming units with microprocessors for bomb and/or reaction calorimetry have been developed by Parr Comp. and Leco Comp. (USA). The latest modification of the Technicon flow analyzer permits on-line analysis of solid samples. For thermochemical titrations, the Sanda titrator (USA) and Vaskut automatic titrator (Hungary) are available. In the USA, the Tronac isothermal or isoperibol calorimeters are widely used. At the Technical University of Brno, ?SSR, smaller table instruments with a water-bath are applied for different modes of solution thermochemical analysis, and also for the reactions of solid samples in liquids. For the measurement of very small temperature differences, PTC thermistors are used. The possibilities of the future development of measuring techniques are outlined. 相似文献
45.
Unit cell parameters have been calculated from x-ray powder diffraction data of Mo2Br4
Py
4 (A), Mo2I4
Py
4 (B), Mo2I4
Pic
4 (C), Mo2(SCN)4
Py
4 (D) and Mo2(SCN)4
Pic
4 (E), A, B and C crystallize tetragonal. A witha=9,42,c=15,O2 Å; B witha=9,46,c=14,98 Å and C witha=9,66 andc=15,72 Å D and E crystallize orthorhombic. D witha=10,09,b=9,14,c=15,08 Å; E witha=10,22,b=9,41 andc=15,15 Å.Py=pyridine,Pic=4-methylpyridine. 相似文献
46.
M. Kabešová I. Vargová T. Šramko J. Gažo 《Journal of Thermal Analysis and Calorimetry》1978,13(1):65-70
The influence of the position of the CH3 group in picoline and lutidine ligands on the degree of chemical change of the NCS groups in coordination compounds of the type Cu(NCS)2L2 (whereL=2-, 3- and 4-picoline, and 2,3-, 2,4-, 2,5-, 2,6-, 3,4- and 3,5-lutidine) is dealt with. The most marked effect of the CH3 group is found to be exerted in position 4. This effect of the methyl group on the degree of chemical change points to the mutual influence of the ligands in coordination compounds of Cu(II).
Zusammenfassung Der Artikel befaßt sich mit dem Einfluß der Lage der CH3 Gruppe in Pikolinen und Lutidinen als Liganden auf den Grad der chemischen Änderungen der Gruppen NSC in Koordinationsverbindungen des Typs Cu(NCS)2L2 (L=2-, 3- und 4-Pikoline, 2,3-, 2,4-, 2,5-, 2,6-, 3,4- und 3,5-Lutidine). Der ausgeprägteste Effekt der CH3 Gruppe wurde in der Position 4 beobachtet. Dieser Einfluß der Methylgruppe auf das Ausmaß der chemischen Änderungen deutet auch auf die gegenseitige Wirkung der Liganden in Koordinationsverbindungen von Cu(II).
Résumé L'article a trait à l'influence de la position du groupe CH2 dans les picolines et lutidines, en tant que ligands, sur le degré des changements chimiques des groupes SCN dans les composés de coordination du type Cu(SCN)2L2 (L=2-, 3 et 4-picoline, 2,3-, 2,4-,2,5-, 2,6-, 3,4- et 3,6-lutidine). L'effet le plus prononcé du groupe CH3 s'observe en position 4. Cette influence du groupe méthyle sur le degré des changements chimiques indique aussi l'influence mutuelle des ligands dans les composés de coordination du Cu(II).
- , , NCS Cu(NCS)2,L2, L=2-, 3- 4- , 2.3-, 2.4-, 2.5-, 2.6-, 3.4- 3.5-. , 4. Cu(II).相似文献
47.
Twenty laboratories from 17 countries around the world participated in two analytical quality control exercises, coded NAT-5
and NAT-6, on determining trace and minor elements in plant bioindicator samples. 1398 laboratory mean values for 51 elements
were submitted for two lichen and two moss materials. The submitted measurement results were evaluated as interlaboratory
comparison (IC) exercises and as proficiency tests (PT) following standard procedures developed by the International Atomic
Energy Agency (IAEA). The evaluations confirmed good performance of the participating laboratories for many elements. Furthermore,
the laboratories performance based on IC criteria improved from the first exercise to the second one. Subsequent NAT-5 evaluation
revealed systematic differences between the analytical values obtained non-destructively or after the total sample dissolution
and the measurements following nitric acid sample dissolution (without the use of hydrofluoric acid) for some elements. The
most critical elements for this kind of discrepancies appeared to be Al, Ca, Cr, Fe, Na, Ni, and Pb. After changing analytical
methodologies in the concerned laboratories, more consistent values for those elements were obtained in NAT-6.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
48.
The thermal behaviour of N2H6GeF6 · H2O was investigated by TG, DTG and DTA measurements. The decomposition proceeded in three steps, in which anhydrous N2H6GeF6 and N2H5GeF5; were isolated and characterized by chemical analysis and vibrational spectroscopy. The X-ray powder photographs of the intermediates were indexed, namely, for N2H6GeF6 on the basis of a monoclinic cell with a = 8.86(9), b = 9.29(2), c =7.40(0) Å, β = 85° and for N2H5GeF5 on the basis of an ortrhorhombic cell with a = 8.43(5),b = 9.19(9), c = 7.43(6) Å. 相似文献
49.
Jasmina M. Dimitrić Marković Zoran S. Marković Jelisaveta M. Baranac Marina L. Dašić 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1225-1232
Summary. The study of delphinidin complexation with trivalent aluminum in acidic aqueous buffered (pH 3.0 and 3.8) and methanolic solutions was performed utilizing electronic absorption spectroscopy and quantum chemical calculations.
In its structure delphinidin possesses several chelating sites in competition towards aluminum(III). Molar ratio plots denoted
the formation of only one aluminum(III):delphinidin complex of stoichiometry of 1:1 in both investigated media. Semiempirical
calculations, performed at the restricted HF AM1 level, enabled the determination of the structural features of free delphinidin and structural modifications caused by
chelation of aluminum(III). Considering the pigment molecular structure and the results of the theoretical calculations it
is possible to equally implicate C3′–C4′ and C4′–C5′ hydroxyl groups as those with the predominant chelating power. 相似文献
50.
Zusammenfassung Eine Methode der Identifizierung von Alkyl- und Arylgruppen organischer Sulfide wurde ausgearbeitet, die die Spaltung dieser Stoffe mit Raney-Nickel zur gaschromatographischen Bestimmung der dabei entstandenen Kohlenwasserstoffe ausnützt.
Die Autoren danken den Kollegen Dr.M. Veea, Ing.J. Petránek und Ing.J. Gaspari für die Überlassung von Proben organischer Sulfide. 相似文献
Summary A method was developed for identifying alkyl- and aryl groups of organic sulfides. The method employs the cleavage of these materials with Raney nickel for the gas chromatographic determination of the resulting hydrocarbons.
Résumé On a mis au point une méthode d'identification des groupes alkylés et arylés des sulfures organiques exploitant la dissociation de ceux-ci par le nickel Raney pour le dosage par chromatographic en phase gazeuse des carbures d'hydrogène qui se forment.
Die Autoren danken den Kollegen Dr.M. Veea, Ing.J. Petránek und Ing.J. Gaspari für die Überlassung von Proben organischer Sulfide. 相似文献