Use of ultrasonic nebulizer with desolvator membrane for the determination of titanium and zirconium in human serum by means of inductively coupled plasma – mass spectroscopy

A technique for the determination of titanium and zirconium in human blood serum, after pressurized digestion utilizing ICP-MS coupled to an ultrasonic nebulizer (USN) and desolvating membrane is described. As no CRM for titanium is available, zirconium has been determined in order to demonstrate the accuracy of the technique, as the limits in blood are well known. Bone cement consists basically of a polymer, namely polymethylmethacrylate (PMMA). For better X-ray contrast some manufacturers use incorporated ZrO₂ with a volume fraction of 10 to 15%. Thus, the zirconium present in the PMMA matrix can be used as an indicator for the PMMA particulate debris.     

Gamma-ray spectroscopy with relativistic exotic heavy-ions

Feasibility of gamma-ray spectroscopy at relativistic energies with exotic heavy-ions and new generation of germanium detectors (segmented Clover) is discussed. An experiment with such detector array and radioactive is discussed.     

Catalytic ignition of ionic liquids for propellant applications

In this proof of concept study, the ionic liquids, 2-hydroxyethylhydrazinium nitrate and 2-hydroxyethylhydrazinium dinitrate, ignited on contact with preheated Shell 405 (iridium supported on alumina) catalyst and energetically decomposed with no additional ignition source, suggesting a possible route to hydrazine replacements.     

High‐Temperature Spray‐Dried Polymer/Bacteria Microparticles for Electrospinning of Composite Nonwovens

Living Micrococcus luteus (M. luteus) and Escherichia coli (E. coli) are encapsulated in poly(vinyl alcohol), poly(vinylpyrrolidone), hydroxypropyl cellulose, and gelatin by high‐temperature spray drying. The challenge is the survival of the bacteria during the standard spray‐drying process at temperatures of 150 °C (M. luteus) and 120 °C (E. coli). Raman imaging and transmission electron microscopy indicate encapsulated bacteria in hollow composite microparticles. The versatility of the spray‐dried polymer bacteria microparticles is successfully proved by standard polymer solution–processing techniques such as electrospinning, even with harmful solvents, to water‐insoluble polyacrylonitrile, polystyrene, poly(methyl methacrylate), and poly(vinyl butyrate) nanofiber nonwovens, which opens numerous new opportunities for novel applications.     

The formal translation equation for iteration groups of type II

We investigate the translation equation $$F(s+t, x) = F(s, F(t, x)),\quad \quad s,t\in{\mathbb{C}},\qquad\qquad\qquad\qquad({\rm T})$$ in ${\mathbb{C}\left[\kern-0.15em\left[{x}\right]\kern-0.15em\right]}$ , the ring of formal power series over ${\mathbb{C}}$ . Here we restrict ourselves to iteration groups of type II, i.e. to solutions of (T) of the form ${F(s, x) \equiv x + c_k(s)x^k {\rm mod} x^{k + 1}}$ , where k ≥ 2 and c _k ≠ 0 is necessarily an additive function. It is easy to prove that the coefficient functions c _n (s) of $$F(s, x) = x + \sum_{n \ge q k}c_n(s)x^n$$ are polynomials in c _k (s). It is possible to replace this additive function c _k by an indeterminate. In this way we obtain a formal version of the translation equation in the ring ${(\mathbb{C}[y])\left[\kern-0.15em\left[{x}\right]\kern-0.15em\right]}$ . We solve this equation in a completely algebraic way, by deriving formal differential equations or an Aczél–Jabotinsky type equation. This way it is possible to get the structure of the coefficients in great detail which are now polynomials. We prove the universal character (depending on certain parameters, the coefficients of the infinitesimal generator H of an iteration group of type II) of these polynomials. Rewriting the solutions G(y, x) of the formal translation equation in the form ${\sum_{n\geq 0}\phi_n(x)y^n}$ as elements of ${(\mathbb{C}\left[\kern-0.15em\left[{x}\right]\kern-0.15em\right])\left[\kern-0.15em\left[{y}\right]\kern-0.15em\right]}$ , we obtain explicit formulas for ${\phi_n}$ in terms of the derivatives H ^(j)(x) of the generator ${H}$ and also a representation of ${G(y, x)}$ as a Lie–Gröbner series. Eventually, we deduce the canonical form (with respect to conjugation) of the infinitesimal generator ${H}$ as x ^k + hx ^2k-1 and find expansions of the solutions ${G(y, x) = \sum_{r\geq 0} G_r(y, x)h^r}$ of the above mentioned differential equations in powers of the parameter h.     

Raman spectroscopy on single- and multi-walled nanotubes under high pressure

The pressure dependence of the high-energy Raman modes in single- and multi-walled carbon nanotubes was measured in the range 0–10 GPa. We found the pressure coefficient to be linear in both materials but 25% smaller in MWNT. Given that the curvature effects on vibrational properties of the rolled-up graphene sheets are small, we can explain this difference simply with elasticity theory. Received: 17 May 1999 / Accepted 18 May 1999 / Published online: 4 August 1999     

Schwingungsspektroskopische Untersuchungen an den Organohydrogensilanen (XCH2)(CH3)2SiH (X = Cl,Br, J), X(YO)2SiH (X = CH3, C2H5/Y = CH3, C2H5 … tert.-C4H9), (C6H5)2SiH2 und C6H5SiH3

Infrared and Raman Spectroscopic Investigations on the Organosubstituted Silicon Hydrides (XCH₂)(CH₃)₂SiH (X = Cl, Br, J), X(YO)₂SiH (X = CH₂, C₂H₅/Y = CH₃, C₂H₅ … tert.-C₄H₉), (C₆H₅)₂SiH₂ and C₆H₅SiH₃ Typical band splittings, specially for the SiH stretching vibration, are shown in the infrared and Raman spectra of the silicon hydrides (XCH₂)(CH₃)₂SiH (X = Cl, Br, J), and X(YO)₂SiH (X = CH₃, C₂H₅/Y = CH₃, C₂H₅ … tert.-C₄H₉). The cause of this behavior is in all probability the existence of rotational isomers. Raman polarization measurements at organosubstituted silicon di- and trihydrides demonstrate the accidental degeneracy of the SiH valence vibrations.