разделение изотопных молекул водорода на водородных формах синтетичеескх цеолитов

Anhand der Äquivalenz zwischen der Kaliummenge und der entsprechenden Zählrate (⁴⁰K) werden Beziehungen angegeben, die es ermöglichen, die Kaliummenge zu bestimmen, deren radiometrischer Einfluβ bei verschiedenen Gesamieffektivitäten vernachlässigbar ist. Für die häufigsten Fälle von Gesamtaktivitätsmessungen von Spaltproduktgemischen mit Hilfe der β-Strahlung sind die radiometrisch vernachlässigbaren Kaliummengen für einige Nahrungsmittel angeührt.     

Role of the oxygen partial pressure in the formation of composite Co-CoO nanoparticles by reactive aggregation

The magnetic properties of diluted films composed of nanocomposite Co-CoO nanoparticles (of ~8 nm diameter) dispersed in a Cu matrix have been investigated. The nanoparticles were formed in an aggregation chamber by sputtering at different Ar/O₂ partial pressures (0?C0.015). The exchange-bias properties appear to be insensitive to the amount of O₂ during their formation. However, the temperature dependence of the magnetization, M(T), exhibits two different contributions with relative intensities that correlate with the amount of O₂. The magnetic results imply that two types of particles are formed, nanocomposite Co-CoO (determining the exchange-bias) and pure CoO, as confirmed by transmission electron microscopy observations. Importantly, as the O₂ partial pressure during the sputtering is raised the number of nanocomposite Co-CoO nanoparticles (exhibiting exchange-bias properties) is reduced and, consequently, there is an increase in the relative amount of pure, antiferromagnetic CoO particles.     

Oпpeдeлehиe othocиteлъhoгo pacпoлoжehия heкomБиhиpyющиx элeкtpohhъix coctoяhий дbyxatomhъix moлeкyл. Ochobhoe элeкtpohhoe coctoяhиe ZrO

A method is proposed for determining the energy difference of noncombining electronic states and the type of ground electronic state of molecules, based on studying the temperature dependence of integral absorption coefficients of molecular bands in a reflected shock wave plasma over a wide range of temperatures. The method is used to determine the relative position of singlet and triplet ZrO electronic states. As the result of measurements of integral absorption coefficients of 0, 0 bands of ${}^1\text{Σ}{}^{\mathrm{+}}\text{-}{}^1\text{Σ}{}^{\mathrm{+}}$ and ${}^3\text{Δ -}{}^3\text{Δ}$ systems in the temperature interval 3370–5200°K, it is shown that ¹Σ⁺ state is the ZrO ground state, whilst T₀(a³Δ) = 1700 ± 250 cm^-1.     

Early recognition of oxidative degradation in polymers by chemiluminescence

Most common polymers degrade readily during normal use by reaction with oxygen. Rapid screening tests are requested by industry to characterise the oxidative stability of the materials. The chemiluminescence (CL) method, which is based on the fact that oxidation reactions of most organic materials, including polymers, are accompanied by weak emission of light, has the potential for being such a test. Selected examples of CL measurements, in a commercially available instrumentation, on different kind of materials and material formulations (as used in industrial applications) clearly indicate that the CL technique is capable of determining the relative oxidative stability of polymers at very early stages of degradation.