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151.
Adam Rudziński Anna Tyszka-Zawadzka Paweł Szczepański 《Optical and Quantum Electronics》2007,39(4-6):501-510
The aim of this paper is to present the analysis of influence of defects in 1D photonic crystal (PC) on the density of states
and simultaneously spontaneous emission, in both spatial and frequency domains. In our investigations we use an analytic model
of 1D PC with defects. Our analysis reveals how presence of a defect causes a defect mode to appear. We show that a defect
in 1D PC has local character, being negligible in regions of PC situated far from the defected elementary cell. We also analyze
the effect of multiple defects, which lead to photonic band gap splitting. 相似文献
152.
Dutka M Gurbiel RJ Kozioł J Froncisz W 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,170(2):5786-227
Applicability of continuous wave multiquantum EPR methods to study relaxation times at X-band is examined. Multiquantum transitions excited in a two-level system by tetrachromatic irradiation are used for these studies. The Bloch equation model is applied to simulate lineshapes of the three quantum transitions as a function of frequency difference between exciting fields. The dependence of multiquantum transition signals on relaxation times and microwave amplitude is shown. On this basis a method of deducing relaxation times from these signals is formulated. The case of a homogeneously and inhomogeneously broadened resonance line is considered. Two experimental methods are used to verify the proposed hypothesis: the X-band continuous wave multiquantum EPR with four frequencies microwave field and saturation recovery EPR. The values of T1 obtained from CW MQ EPR and SR EPR are compared. 相似文献
153.
Luis Anchordoqui María Teresa Dova Thomas McCauley Stephen Reucroft 《Annals of Physics》2004,314(1):145-207
The properties of cosmic rays with energies above 106 GeV have to be deduced from the spacetime structure and particle content of the air showers which they initiate. In this review we summarize the phenomenology of these giant air showers. We describe the hadronic interaction models used to extrapolate results from collider data to ultra high energies, and discuss the prospects for insights into forward physics at the LHC. We also describe the main electromagnetic processes that govern the longitudinal shower evolution, as well as the lateral spread of particles. Armed with these two principal shower ingredients and motivation from the underlying physics, we provide an overview of some of the different methods proposed to distinguish primary species. The properties of neutrino interactions and the potential of forthcoming experiments to isolate deeply penetrating showers from baryonic cascades are also discussed. We finally venture into a terra incognita endowed with TeV-scale gravity and explore anomalous neutrino-induced showers. 相似文献
154.
Parracino A Gajula GP di Gennaro AK Neves-Petersen MT Rafaelsen J Petersen SB 《Journal of fluorescence》2011,21(2):663-672
Medical interest in nanotechnology originates from a belief that nanoscale therapeutic devices can be constructed and directed
towards its target inside the human body. Such nanodevices can be engineered by coupling superparamagnetic nanoparticle to
biomedically active proteins. We hereby report the immobilization of a PhEst, a S-formylglutathione hydrolase from the psychrophilic
P. haloplanktis TAC125 onto the gold coated surface of modified superparamagnetic core-shell nanoparticles (Fe3O4@Au). The synthesis of the nanoparticles is also reported. S-formylglutathione hydrolases constitute a family of ubiquitous
enzymes which play a key role in formaldehyde detoxification both in prokaryotes and eukaryotes. PhEst was originally annotated
as a putative feruloyl esterase, an enzyme that releases ferulic acid (an antioxidant reactive towards free radicals such
as reactive oxygen species) from polysaccharides esters. Dynamic light scattering, scanning electron microscopy with energy
dispersive X-ray spectroscopy, UV–visible absorption spectroscopy, fluorescence spectroscopy, magnetic separation technique
and enzyme catalytic assay confirmed the chemical composition of the gold covered superparamagnetic nanoparticles, the binding
and activity of the enzyme onto the nanoparticles. Activity data in U/ml confirmed that the immobilized enzyme is approximately
2 times more active than the free enzyme in solution. Such particles can be directed with external magnetic fields for bio-separation
and focused towards a medical target for therapeutical as well as bio-sensor applications. 相似文献
155.
J. Sarnecki G. Gawlik M. Teodorczyk O. Jeremiasz R. Kozłowski D. Lipiński K. Krzyżak A. Brzozowski 《Opto-Electronics Review》2011,19(4):486-490
A new concept of edge illuminated solar cells (EISC) based on silicon epitaxial technique has been proposed. In this kind
of photovoltaic (PV) devices, sun-light illuminates directly a p-n junction through the edge of the structure which is perpendicular
to junction surface. The main motivation of the presented work is preparation of a working model of an edge-illuminated silicon
epitaxial solar cell sufficient to cooperation with a luminescent solar concentrator (LSC) consisted of a polymer foil doped
with a luminescent material. The technological processes affecting the cell I–V characteristic and PV parameters are considered. 相似文献
156.
Stock indexes for some European emerging markets are analyzed using an investment-horizon approach. Austrian ATX index and Dow Jones have been studied and compared with several emerging European markets. The optimal investment horizons are plotted as a function of an absolute return value. Gain–loss asymmetry, originally found for American DJIA index, is observed for all analyzed data. It is shown, that this asymmetry has different character for emerging and for established markets. For established markets, gain curve lies typically above loss curve, whereas in the case of emerging markets the situation is just the opposite. We propose a measure quantifying the gain–loss asymmetry that clearly exhibits a difference between emerging and established markets. 相似文献
157.
158.
Back BB Baker MD Ballintijn M Barton DS Becker B Betts RR Bickley AA Bindel R Budzanowski A Busza W Carroll A Decowski MP García E Gburek T George N Gulbrandsen K Gushue S Halliwell C Hamblen J Harrington AS Henderson C Hofman DJ Hollis RS Hołyński R Holzman B Iordanova A Johnson E Kane JL Khan N Kulinich P Kuo CM Lee JW Lin WT Manly S Mignerey AC Noell A Nouicer R Olszewski A Pak R Park IC Pernegger H Reed C Remsberg LP Roland C Roland G Sagerer J Sarin P Sawicki P Sedykh I Skulski W Smith CE 《Physical review letters》2003,91(7):072302
We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt[s(NN)]=200 GeV. The spectra were obtained for transverse momenta 0.25
相似文献
159.
A. Odrzywołek 《The European Physical Journal C - Particles and Fields》2007,52(2):425-434
The spectrum of the neutrinos produced in the massive photon and longitudinal plasmon decay process has been computed with
four levels of approximation for the dispersion relations. Some analytical formulae in the limit cases are derived. Interesting
conclusions related to previous calculations of the energy loss in stars are presented. The high energy tail of the neutrino
spectrum is shown to be proportional to exp(-E/kT), where E is the neutrino energy and kT is the temperature of the plasma.
PACS 97.90.+j; 97.60.-s; 95.55.Vj; 52.27.Ep 相似文献
160.
M. Wołoszyn D. Stauffer K. Kułakowski 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(3):331-335
We investigate the network model of community by Watts, Dodds and Newman (D.J. Watts et al., Science 296, 1302 (2002)) as a hierarchy of groups, each of 5 individuals. A homophily parameter
α controls the probability proportional to exp (-αx) of selection of neighbours
against distance x. The network nodes are endowed with spin-like variables si = ± 1,
with Ising interaction J > 0. The Glauber dynamics is used to investigate the
order-disorder transition. The transition temperature Tc is close to 3.8 for
α < 0.0 and it falls down to zero above this value. The result provides a mathematical
illustration of the social ability to a collective action via weak ties, as discussed
by Granovetter in 1973. 相似文献