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1.
M. Kameswara Rao M. Sharma S. K. Raza D. K. Jaiswal 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):559-566
The synthetic standards for cysteine and valine adducts of sulphur mustard have been synthesized using 2-(2-chloroethylthio) ethanol (half-mustard). These adducts have been recognized as biomarkers for exposure to sulphur mustard. The adducts have been fully characterized using 1 H and 13 C NMR spectroscopy and mass spectrometric techniques. 相似文献
2.
B. Witzel N.A. Papadogiannis D. Charalambidis 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,12(1):21-25
A new device for charged particle coincidence experiments in strong-field, short pulse laser-atom/molecule interactions is
presented. The device consists of a single time of flight spectrometer, common for both positive and negative charge detection.
Experimental parameters required for the use of the device in the high intensity regime are discussed. A demonstration of
electron-ion coincidence measurements in the interaction of Xe atoms with 60 fs laser pulses at 800 nm and an intensity of
W/cm2 is reported.
Received 22 November 1999 相似文献
3.
J. Xu W. Li T. Ma Z. Li W. Lu K. Chen 《Applied Physics A: Materials Science & Processing》2000,71(6):651-655
Thin layers of hydrogenated amorphous carbon were prepared by using organic hydrocarbon source, xylene (C8H10), in plasma-enhanced chemical vapor deposition (PECVD) system. The microstructures were characterized by using Fourier-transform
infrared and Raman scattering spectra. The appearance of a sharp vibration signal in 1600 cm-1 strongly suggests the existence of sp2 carbon clusters with aromatic rings. With increasing the deposition rf power, the content of these aromatic structures is
increased in the films. In contrast to a broad single PL peak in methane (CH4)-baseda-C:H films, the PL band of xylene-based a-C:H films contains multiple peaks in blue-green light region, which is influenced
by rf power. We tentatively attributed it to the radiative recombination of electron-hole pairs through some luminescent centers
associated with aromatic structures.
Received: 26 April 2000 / Accepted: 9 May 2000 / Published online: 13 September 2000 相似文献
4.
Reinhold Tacke Klaus Rafeiner Carsten Strohmann Ernst Mutschler Günter Lambrecht 《应用有机金属化学》1989,3(2):129-132
The synthesis of the potent and highly selective silicon-containing antimuscarinic agent o-methoxysila-hexocyclium methyl sulfate and its corresponding tertiary amine (isolated as the dihydrochloride) is described. The quarternary compound is an o-methoxy derivative of sila-hexocyclium methyl sulfate, which represents one of the tools currently used in experimental pharmacology for the subclassification of muscarinic receptors. The o-methoxy derivative, the pharmacological profile of which differs substantially from that of the nonmethoxy compound, is also recommended as a tool for the investigation of muscarinic receptor heterogeneity. 相似文献
5.
Novel chirally symmetric fermion actions containing the minimum amount of fermion doubling have been recently proposed in the literature. We study the symmetries and renormalization of these actions and find that in each case, discrete symmetries, such as parity and time-reversal, are explicitly broken. Consequently, when the gauge interactions are included, these theories radiatively generate relevant and marginal operators. The restoration of these symmetries and the approach to the continuum limit thus require the fine-tuning of several parameters. With some assumptions, we show that this behavior is expected for actions displaying minimal fermion doubling. 相似文献
6.
D. Cortina-Gil T. Baumann H. Geissel H. Lenske K. Sümmerer L. Axelsson U. Bergmann M.J.G. Borge L.M. Fraile M. Hellström M. Ivanov N. Iwasa R. Janik B. Jonson K. Markenroth G. Münzenberg F. Nickel T. Nilsson A. Ozawa K. Riisager G. Schrieder W. Schwab H. Simon C. Scheidenberger B. Sitar T. Suzuki M. Winkler 《The European Physical Journal A - Hadrons and Nuclei》2001,10(1):49-56
One-neutron removal cross-sections ( ) of 17, 19C in various targets at about 900 MeV/nucleon, and one-proton removal cross-sections ( ) of 8, 10B at about 1400 MeV/nucleon were measured using the fragment separator FRS at GSI. A significant increase of for 19C compared to its neighbors was observed. The same behavior was found for for the neutron-deficient nucleus 8B compared to the stable isotope 10B. These results support a one-neutron halo structure in 19C and a one-proton halo in 8B.
Received: 26 July 2000 / Accepted: 11 January 2001 相似文献
7.
It has recently been shown that the maximal kinematical invariance group of polytropic fluids, for smooth subsonic flows, is the semidirect product of SL (2, R) and the static Galilei group G. This result purports to offer a theoretical explanation for an intriguing similarity, that was recently observed, between a supernova explosion and a plasma implosion. In this paper we extend this result to discuss the symmetries of discontinuous flows, which further validates the explanation by taking into account shock waves, which are the driving force behind both the explosion and implosion. This is accomplished by constructing a new set of Rankine-Hugoniot conditions, which follow from Noether’s conservation laws. The new set is dual to the standard Rankine-Hugoniot conditions and is related to them through the SL (2, R) transformations. The entropy condition, that the shock needs to satisfy for physical reasons, is also seen to remain invariant under the transformations. 相似文献
8.
K. Goeke J. Ossmann P. Schweitzer A. Silva 《The European Physical Journal A - Hadrons and Nuclei》2006,27(1):77-90
The dependence of the nucleon mass on the mass of the pion is studied in the framework of the chiral quark-soliton model.
A remarkable agreement is observed with lattice data from recent full dynamical simulations. The possibility and limitations
to use the results from the chiral quark soliton model as a guideline for the chiral extrapolation of lattice data are discussed. 相似文献
9.
K. Rerbal I. Solomon J.-N. Chazalviel F. Ozanam 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,51(1):61-64
We have investigated the temperature dependence of
photoluminescence in hydrogenated amorphous silicon-carbon alloys
a-Si1-xCx:H prepared by glow discharge in the low-power regime.
The radiative recombination process, due to photocarriers trapped on
band-edge states, is in competition with the thermal escape of the
photocarriers into the mobility bands. The model gives a quantitative fit
with experiment, without any adjustable parameter, provided the width of the
band-edge distribution of states is taken as the width of the conduction
band only (measured by “photo-induced infra-red spectroscopy”) and not as
the Urbach energy, as it is usually assumed. 相似文献
10.
V. Palyok I.A. Szabó D.L. Beke A. Kikineshi 《Applied Physics A: Materials Science & Processing》2002,74(5):683-687
Surface relief formation at holographic recording on amorphous selenium films was demonstrated and investigated. The presence
of this optical phase modulation component is essential for ensuring significant, stable and erasable optical recording in
a-Se films at 290–320 K temperatures, where conventional photodarkening was known as insignificant and unstable. Photocrystallization
can only be observed in super-exposed a-Se films at the given experimental conditions of hologram recording. Erasing behavior
of surface relief gratings under heat treatment was also investigated in order to reveal further details of the mechanism.
Photoinduced structural transformations within the amorphous phase, connected to local ordering under the condition of light-induced
fluidity, are proposed as an explanation for the relief formation and erasing. The observed reversible optical recording process
may be useful for the various optoelectronic applications of photoconductive a-Se layers.
Received: 12 June 2000 / Accepted: 6 June 2001 / Published online: 30 August 2001 相似文献