A note on statistical inference for a class of diffusions and approximate diffusions

Some optimal inference results for a class of diffusion processes, including the continuous state branching process and the approximate Wright-Fisher model with selection, are derived.It is then showed how the theory of convergence of experiments, due to Le Cam, can be applied to derive corresponding results for processes approximating these diffusions.     

Poisson brackets and clebsch representations for magnetohydrodynamics,multifluid plasmas,and elasticity

Poisson brackets are constructed by the same mathematical procedure for three physical theories: ideal magnetohydrodynamics, multifluid plasmas, and elasticity. Each of these brackets is given a simple Lie-algebraic interpretation. Moreover, each bracket is induced to physical space by use of a canonical Poisson bracket in the space of Clebsch potentials, which are constructed for each physical theory by the standard procedure of constrained Lagrangians.     

Methods of element analysis by the use of charged particles from the Hamburg Isochronous Cyclotron

The applicability of charged particles induced cyclic activation analysis as well as elastic scattering reactions are investigated to determine elemental concentrations in environmental material. The nuclear reactions are induced by the well focused proton-(25 MeV) and helium-3 beam (40 MeV) of the Hamburg Isochronous Cyclotron.     

Initiation of free‐radical polymerization by peroxypivalates studied by electrospray ionization mass spectrometry

Initiation by tert‐butyl peroxypivalate (TBPP), tert‐amyl peroxypivalate (TAPP), 1,1,3,3‐tetramethylbutyl peroxypivalate (TMBPP), or 1,1,2,2‐tetramethylpropyl peroxypivalate (TMPPP) of radical polymerization of methyl methacrylate in toluene solution at 90 °C was studied via polymer end‐group analysis using electrospray ionization mass spectrometry (ESI‐MS). Conclusive peak assignments allowed for measuring the type and concentration of the fragments that actually initiate macromolecular growth after thermal decomposition of these peroxypivalates. It was found that the pivaloyloxy radical moiety undergoes instantaneous decarboxylation to yield an initiating tert‐butyl radical. The alkoxy radical moiety, on the other hand, may generate, via β‐scission reaction, different types of carbon‐centered radicals (together with a ketone) or may undergo a 1,5‐H‐shift reaction, by which reaction an oxygen‐centered radical is transformed into a carbon‐centered hydroxy radical. This hydrogen shift reaction was found in case of TMBPP. Surprisingly, no evidence for initiating alkoxy radicals could be found, not even in case of initiation by TBPP, where the intermediate tert‐butoxy radical undergoes a rapid chain‐transfer reaction with the solvent toluene. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4266–4275, 2004     

Quantum Cohomology of Grassmannians

We give elementary proofs of the main theorems about the (small) quantum cohomology of Grassmannians, including the quantum Giambelli and quantum Pieri formulas, the rim-hook algorithm, the presentation, and a recent theorem of Fulton and Woodward about the minimal q-power which appears in a product of two Schubert classes.     

Problems in choosing the organs of roe deer (Capreolus capreolus) as reference material

Analytical and Bioanalytical Chemistry - Within a research programme of the specimen bank the standard operation procedures have to be elaborated for roe deer. The liver seems to be one of the...     

Single-neutron states at high spins in ytterbium nuclei: Evidence for the quenching of static neutron pair correlations

The decay schemes of ^167,168,169Yb are established to the largest angular momenta yet known in stably-deformed rare-earth nuclei using the ¹²⁴Sn(⁴⁸Ca,3–5n) reaction. The systematics of the resulting spectrum of single-neutron states in these and neighbouring Yb isotopes at large and small angular momenta are discussed with regard to that expected in the presence and absence of static neutron-pair correlations. This comparison, together with cranking-model and “gauge-space” analyses, provides evidence for the effective disappearance of static neutron-pair correlations for the odd-N isotopes at ?ω ? 0.38 MeV. A composite empirical spectrum of single-neutron states is constructed for the “unpaired” regime and is compared with cranking calculations.     

The first excited state in the doubly-closed-shell nucleus 132Sn populated in the 0.12 s β−-decay of 132In

A 0.12 ± 0.02 s beta activity assigned to the decay of ¹³²In and populating an excited state at 4041 ± 2 keV in the doubly-closed-shell nucleus ₅₀¹³²Sn₈₂ has been observed. This state is tentatively assigned to arise from the 3^? octupole vibration.     

Study of an Underexpanded Plasma Jet

Supersonic jets (Mach number M = 1.4 – 2.0) of dense plasma were produced by a plasmatron in a pulsed regime. The shock structure was investigated by fast mirror cameras, by the schlieren technique and by probe and spectroscopic methods. It was found that during jet expansion the bow shock ahead the gas-plasma interface and the shock behind it are superimposed with the quasistationary shock structure which includes the Mach disk. Whereas the plasma in the discharge chamber is in LTE (n_E ≈ 5 × 10²³ m^?3, T ≈ 14000 K), the electron density of the expanding jet plasma falls to a plateau value of n_E ≈ 5 × 10¹⁹ m^?3 below the LTE limit. At this phase, the jet plasma formed a ball-like turbulent plasmoid which moves at a subsonic velocity through the air up to some milliseconds.