电子束、离子辅助和离子束溅射三种工艺对光学薄膜性能的影响

运用电子束、离子辅助和离子束溅射三种镀膜工艺分别制备光学薄膜,包括单层氧化物薄膜和增透膜,然后采取一系列测试手段,如Zygo轮廓仪、原子力显微镜、表面热透镜技术和X射线衍射等技术,来分析和研究不同的工艺对这些薄膜性能的不同影响,以判断合理的沉积工艺。     

Zur Anreicherung der stabilen Isotope des Schwefels durch Fest-Flüissig-Austausch unter Verwendung von Ionenaustauschern

An verschiedenen Systemen chemischer Verbindungen wurden Versuche zur Anreicherung des stabilen Isotopes ³⁴S unter Verwendung der Ionenaustauscher Wofatit L 150, SBW und SBK nach den Methoden der Frontalchromatographie und der Bandenverdrāngungschromatographie ausgeführt. Beim Isotopenaustauschsystem Hydrogensulfit (am Ionenaustauscher)/Schwefeldioxid (in wäβriger Lösung) wurden Verfahrensweise und Betriebsparameter hinsichtlich des Anreicherungsgrades optimiert. Mit Hilfe einer einfachen Methode gelang es, aus den Versuchsergebnissen Werle für den elementaren Trennfaktor und die Trennstufenhöhe zu berechnen.     

Füllstandsmessung mit Streustrahlungssonden

Es wird die Abhängigkeit der Impulsdichte vom Füllstand bei Meßanordnungen mit γ-Streustrahlungssonden verschiedener Länge untersucht. Verwendet werden die Nuklide ⁶⁰Co und ¹³⁷Cs. Ein nahezu linearer Anstieg der Impulsdichte mit dem Füllstand wird bei Füllgütern kleiner Ordnungszahl nur bei Sondenlängen L ≥ μ₀ ^?1.erzielt. Der Einfluß des Schüttwinkels und der Dichte des Füllgutes wird diskutiert.     

Dynamics of the Up-Conversion Emission in Holmium Doped Zblan Fiber

The dynamics of up-conversion, green emission under excitation at different infra-red wavelength in Ho^3? doped ZBLAN fiber is reported. Under infrared, 890 nm quasi cw pumping the complicated temporal behavior of the up-conversion signal is strongly influenced by the intermediate ⁵I₅ state cross relaxation. The mechanisms of the observed up-conversion processes are proposed and the time evolution of the ⁵S₂ population is described by the rate equation model. Parameters of the model are determined and numerical simulations of the excited state dynamics are performed.     

A model of melting of rare gases within bubbles of crystalline metal matrix

Abstract

On the basis of experimental results obtained in the present and some other works a model of melting of rare gas solids within bubbles formed in a crystalline metal matrix as a result of ion implantation is proposed. Rare gas solid is supposed to melt on heating at the expense of the bubble volume expansion by emission of a dislocation loop. On this basis the melting temperature can be estimated as one which is enough to provide for a pressure inside a bubble sufficient for the initiation of the dislocation loop punching. Values of melting temperatures obtained in this way are in good agreement with available experimental data.     

1H, 13C and 15N NMR spectral analysis of substituted 1,2,3,4‐tetrahydro‐pyrido[1,2‐a]pyrimidines

The NMR spectroscopic data of a series of thirty‐four 3‐acylpyrido[1,2‐a]pyrimidinium salts are analyzed, which were prepared as either perchlorates or chlorides. Methyl group substituted 3‐aroyltetrahydropyrido[1,2‐a]pyrimidines with the methyl substituent in positions 6, 8 and 9 as well as both in positions 6 and 8 were investigated bearing various aroyl substituents. Unequivocal assignment of all resonances was achieved via two‐dimensional ¹H,¹H‐COSY measurements, ¹H,¹³C and ¹H,¹⁵N HSQC as well as HMBC experiments, and important diagnostic CH and NH couplings in the heteroaromatic ring system are evaluated. The influence of the methyl substituents was analyzed on the proton, carbon and nitrogen shifts. A significant effect of the counter ion on some chemical shifts of the nuclei under discussion of the pyridopyrimidines is found, allowing the indirect detection of the anion, which is confirmed by direct measurement of the ³⁵Cl nucleus of the perchlorates. Copyright © 2013 John Wiley & Sons, Ltd.     

Application of the Salicylate Ion Electrode for the Monitoring of the Electroreduction of Salicylic Acid

Abstract

An ion selective electrode is described for measuring the unreacted salicylate ion concentration during the electroreduction of salicylic acid. Conditions for making measurements are discussed.     

Development of a test strip based on DNA-functionalized gold nanoparticles for rapid detection of mercury(II) ions

A rapid,sensitive,selective and reliable strip assay based on DNA-functionalized gold nanoparticles for Hg²⁺ detection has been developed,with a detection limit 5 nmol/L.The measurement principle was based on thymine-Hg²⁺-thymine(T-Hg²⁺-T) coordination chemistry and streptavidin-biotin interaction.The major advantages of this assay are that results can be read visually without any instrument in less than 10 min and that it does not require any sample pretreatment.