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991.
UV photoexcitation of (t-butylethynyl copper)24 cluster films induces segregation of the crystals into metallic and organic phases and leads to evolve the metallic sheets sandwiched by organic polymers. The growth of the metallic crystals in the plane of the photo-electromagnetic field is attributed due to plasmon-plasmon interaction among nanoparticles embedded in dielectric polymer matrices. The surface enhanced photochemical reaction of residual cluster molecules on the photon incident direction is expected to take an important role for joining the metal particles to produce a metallic sheet. We can apply this phenomenon for photolithographic copper pattern generation on a flexible base plate.  相似文献   
992.
993.
The effect of bifractional composition of conducting filler on the electrical and rheological properties of oligomeric compound was studied.  相似文献   
994.
Raman scattering in glasses is investigated theoretically. The experimental Raman spectra of glasses exhibit a low-frequency peak (at ~10 cm?1) that, as a rule, is attributed to vibrational modes of nanometer-sized structural units (nanocrystallites). It is established that the elastic moduli of nanocrystallites must necessarily be dependent on their sizes due to the Laplace pressure effect. A theory of the low-frequency peak is constructed using a realistic size distribution function of nanocrystallites with allowance made for the Laplace pressure effect and the dissipation of vibrational energy. Within this theory, the shape of the low-frequency peak and its evolution with temperature can be analyzed quantitatively. The proposed approach offers a physical interpretation of the experimental data and provides insight into the relation of the characteristic nanocrystallite sizes to the elastic moduli and surface tension coefficients of materials.  相似文献   
995.
996.
The resistivity of composite nonlinear resistors (varistors) consisting of zinc oxide ceramic and high-density polyethylene, as well as IR spectra and X-ray diffraction patterns taken of the samples, are studied. The component composition of the resistor is shown to influence its resistivity and IR and X-ray spectra.  相似文献   
997.
998.
Various-composition supramolecular complexes of calix[4]resorcinolarene with diglycidyl methylphosphonate were synthesized in organic solvents. The products have well-defined melting points, they are cleaved by acetylation, but remain unchanged on treatment with triethylamine.  相似文献   
999.
Optical images can be used to transport, store and process information in a parallel way. We discuss different results obtained in the domain of ‘quantum imaging’, aiming at exploiting at the same time the quantum properties of optical images and their intrinsic parallelism. We define the notion of standard quantum limit (SQL) in optical resolution, set by the quantum noise of usual coherent light, and show that it can be much lower than the diffraction limit. We also prove that this limit can be circumvented by especially designed nonclassical and multimode light. We present an experiment showing that OPOs oscillating inside an exactly confocal cavity actually produce such transverse multimode nonclassical light. We finally describe another experiment which has surpassed the SQL in the case of beam positioning, both in the 1D and 2D cases.  相似文献   
1000.
Deák  L.  Bottyán  L.  Major  M.  Nagy  D. L.  Spiering  H.  Szilágyi  E.  Tanczikó  F. 《Hyperfine Interactions》2002,144(1-4):45-52
Hyperfine Interactions - Synchrotron Mössbauer Reflectometry (SMR), the grazing incidence nuclear resonant scattering of synchrotron radiation, can be applied to perform depth-selective phase...  相似文献   
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