One-nucleon stripping reactions to discrete levels induced by a 793 MeV16O beam on a208Pb target

One-proton and one-neutron stripping reactions induced by a 793 MeV¹⁶O beam bombarding a²⁰⁸Pb target have been studied at the GANIL facility using a high resolution energy loss magnetic spectrometer. The reactions are governed by two semi classical selection rules which are naturally contained in the one-step EFR-DWBA formalism. Relative intensities of the populated states are well reproduced by this formalism which, on the other hand, fails to predict correctly absolute cross section values.     

Dipole bands and multi-quasiparticle excitations in 193Pb

The nucleus ¹⁹³Pb was populated via the ¹⁶⁸Er(³⁰Si,5n) reaction at a beam energy of 159 MeV and studied with the EUROGAM II spectrometer. Five new dipole Δ I = 1 cascades have been found. These structures have been connected to the level scheme which has been considerably extended up to a spin of ? and an excitation energy of about 8 MeV. Angular distribution coefficients, a₂, have been measured and confirm the dipole character of the in-band transitions. B(M1)/B(E2) ratios have been extracted for the two most intense cascades. The ¹⁹³Pb dipole bands are discussed in comparison with those known in odd lead isotopic series and the structure of the band heads is analyzed in terms of microscopic HF+BCS calculations. The proposed configurations are based on a high-K two quasiproton excitation, π ([505]9/2^t? ? [606]13/2⁺)_K=11^t -, coupled to one or three rotation aligned quasineutrons involving the i_13/2, p _3/2, f_5/2 and/or h{9/2} subshells. The main difference, compared with the heavier lead isotopes, is the presence of large Ω orbitals from the ν (i_13/2) shell near the Fermi surface which are responsible for the increasing band-head spin as A decreases.     

Determination of clotiazepam by HPLC with spectrophotometric and amperometric detection

Summary Spectrophotometric and amperometric detectors were compared for the determination of clotiazepam by HPLC. Methanol-water (6040) containing 0.01 mol/l ammonium acetate and methanol-water (7030) containing 0.01 mol/l acetate buffer pH 4 were used as mobile phase in the spectrophotometric and amperometric detection, respectively. The minimum detectability for the spectrophotometric detection was 20 ng injected and the method was applied for the determination of clotiazepam in serum, whereas for the amperometric detection a limit of detection of 2.5 g injected was obtained, using this technique for clotizepam determination in tablets.

---

Bestimmung von Clotiazepam durch HPLC mit spektralphotometrischer und amperometrischer Detektion

     

Tosylation of 2-(monosubstituted)amino-1,3,4-thiadiazoles

Tosylation of 2-benzylamino- and 2-anilino-5-phenyl-1,3,4-thiadiazoles ( 1a,b ) in the presence of triethylamine affords the ring-sulfonylated products 2a,b which isomerize in a later stage of the reaction to the exocyclic amino-sulfonylated products 3a,b . Acetylation of 1a,b gives the acylamino substituted thiadiazoles 4a,b directly as the only reaction products. The ¹³C nmr data are discussed and their importance for the study of prototropic tautomerism and for structure elucidation of the reaction products is indicated.     

A generalization ofL-splines

A theory of generalized splines is developed for all regular formally self adjoint differential operatorsL with real coefficients. A special case of such operators are those which may be factored in the formL =L ₁ ^* L ₁, such as those related to the generalized splines of Ahlberg, Nilson, and Walsh [1, 2], and theL-splines of Schultz and Varga [6]. Theorems giving unique interpolation, integral relations, and convergence rates are established. IfL has a certain positivity property, a useful extremal result is proven.This research was supported in part by a NASA Traineeship, at the Georgia Institute of Technology.     

Thermal field emission as a mechanism for infrared laser light detection in metal whisker diode

The non-linear current-voltage characteristic of thermally enhanced field emission is proposed to explain the operation of a metal-metal point contact diode used for laser harmonic frequency generation and frequency mixing in the infrared region. This mechanism can explain several experimental observations which appear inconsistent with the previous analysis based on a planar metal-oxide-metal tunneling geometry.     

n-Person games with only 1, n− 1, and n-person coalitions

A symmetric solution is presented for any von Neumann-Morgenstern n-person game when the only coalitions that are not completely defeated contain n– 1 or n players.Portions of this research were supported by a National Science Foundation grant at the University of Michigan and by a Fulbright grant at the Middle East Technical University, Ankara.Mathematics Research Center, The University of Wisconsin, Madison.     

Use of nanomaterials in the European construction industry and some occupational health aspects thereof

In the European construction industry in 2009, the use of engineered nanoparticles appears to be confined to a limited number of products, predominantly coatings, cement and concrete. A survey among representatives of workers and employers from 14 EU countries suggests a high level of ignorance about the availability and use of nanomaterials for the construction industry and the safety aspects thereof. Barriers for a large-scale acceptance of products containing engineered nanoparticles (nanoproducts) are high costs, uncertainties about long-term technical material performance, as well as uncertainties about health risks of nanoproducts. Workplace measurements suggest a modest exposure of construction workers to nanoparticles (NPs) associated with the use of nanoproducts. The measured particles were within a size range of 20–300 nm, with the median diameter below 53 nm. Positive assignment of this exposure to the nanoproduct or to additional sources of ultrafine particles, like the electrical equipment used was not possible within the scope of this study and requires further research. Exposures were below the nano reference values proposed on the basis of a precautionary approach.