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21.
The dependence of the flow stress and the slip band density on the plastic strain has been measured at 201 K, 293 K and 363 K. The growth of deformation concentrated in an average slip band has been stated. The types of obstacles acting against the rise and development of a slip band and the temperature dependence of the strain hardening in AgCl crystals are discussed. An equation stating the dependence of the flow stress on the slip band density is presented. The hardening in AgCl crystals is classified as the stage III — hardening.  相似文献   
22.
A hybrid method for measuring the electron distribution function in the low temperature plasma is described. The time resolution of the measurement is of the order of several sec.  相似文献   
23.
The valence electron states of layered semiconductor GaS were studied by polarizedK X-ray emission bands. The polarized gallium and sulphurK bands were calculated and GaK2-bands were measured by the two crystal spectrometer. In the calculations the self-consistent pseudo-potential method was applied. Thep x ,p y p z -character and localisation of valence electron states were identified. Comparison with the results of controversial interpretation of photoemission and tight binding calculations were done and analysed in detail.We are indebted to J. Mikkelsen from Xerox Research Center in Palo Alto for kindly sending us the GaS single crystals.  相似文献   
24.
Multiplicity distributions up to the Collider energies could be described by various two-parameter compounded distributions having in common Poisson distributed number of clusters. Among them the logarithmic distribution for hadronization via decaying clusters leads to energyindependent number of clusters above the ISR energies, replacing the previous KNO-scaling.Dedicated to the 30th anniversary of the Joint Institute for Nuclear Research.  相似文献   
25.
LetX be a leftA-module, whereA is either a complex Banach *-algebra with an identity element or the field of quaternions. The main result of this note is that forQ, anA-quadratic functional defined onX, there exists a sesquilinear functionalB such thatB(x,x)=Q(x) holds for allxX.  相似文献   
26.
The structure of the complex Ag·TBDTPP (tetrabutyl S-dithiopyrophosphate) formed in HNO3 medium was studied by IR and NMR methods. The complex is involved in the isomerization of TBDTPP in the presence of Ag+ and NO 3 ions. In the IR spectra, we observe the disappearance of P−O−P band and the occurrence of new absorption bands associated with P−S−P and P=O bonds. The silver ion is coordinated to the thiophosphoryl group of the isomer molecule. The influence of HNO3 concentration on complex formation is discussed.  相似文献   
27.
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   
28.
Thermal analysis supported by kinetic calculations was applied exhaustively to these compounds. Under dynamic conditions, tetrafluorometallates(III), which as intermediates, could not be isolated, for the first three compounds. In each case, the final step was the pure metal(III) fluoride. Ammonium hexafluorochromate(III) decomposed directly to the pure chromium(III) fluoride. The decomposition rate of all compounds slowed down towards the end, probably for kinetic reasons. Polymorphic transitions of ammonium hexafluorotitanate(III) were observed at 35 and 100°C. Ammoniumhexafluoroscandate(III) underwent polymorphic transition at 47°C. The decomposition patterns for all these compounds were similar. Conditions for the preparation of pure ammonium tetrafluorometallates(III) of Sc, Ti and V are described.  相似文献   
29.
Summary A gas Chromatographic determination of traces of alkali metal O,O-diethyl phosphorodithioates is described. The salts were converted into a volatile derivative by alkylation with diazomethane. The product was identified by gas chromatography-mass spectrometry. With aqueous samples a linear relationship of peak height to amount of salt was obtained in the range 0.04–1 ng and for urine samples a calibration curve was constructed. The detection limit (signal to noise ratio 4/1) was 40 pg of salt. The procedure was successfully used for monitoring phosalone absorption by occupationally exposed persons.
Zusammenfassung Eine gaschromatographische Bestimmung von Spuren Alkalisalz des Diäthyldithiophosphorsäureesters wurde beschrieben. Die Salze wurden durch Alkylieren mit Diazomethan in ein flüchtiges Derivat übergeführt. Dessen Identifizierung erfolgte mittels eines gaschromatographisch-massenspektrometrischen Systems. In Wasserproben wurde ein lineares Verhältnis der Peakhöhen und der Salzmenge festgestellt und für Urinproben wurde eine Eichkurve ermittelt. Die Nachweisgrenze (Signal zu Rausch 41) wurde bei 40 pg Salz festgestellt. Die Methode wurde für die Kontrolle der Absorption von Phosalon bei beruflich exponierten Personen erfolgreich angewendet.


Presented at the Fourth International Congress of Pesticide Chemistry (IUPAC), Zürich, July 24–28, 1978.  相似文献   
30.
The IR- and Raman Spectra of several compounds of the stoichiometryM 2 I M IIIF5H2O and their deuterated analogs have been interpreted on the basis of their crystal structures. The compounds studied were divided into two classes regarding the bonding of water molecules. The main spectroscopic difference between the two classes was found in the region of H2O vibrations in good agreement with theoretical predictions. The metal—fluorine and metal—oxygene vibrations gave no direct information concerning the two types of water.  相似文献   
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