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101.
Experimental consequences of pheripheral production of NN pairs are described and contrasted with an orthogonal set of predictions which follow if NN production occurs in central collisions. It is shown that current ISR experiments can easily distinguish between the two viewpoints, for example by measuring the average multiplicity associated with p production.  相似文献   
102.
Multiferroics conventionally refer to the materials exhibiting co-existing electric, magnetic, and structure order parameters. Interplay between ferroelectricity, magnetism, and ferroelasticity in a single phase makes multiferroics truly multifunctional providing control over magnetic and electric ordering by applying electric and magnetic fields, respectively. Incorporation of multiferroic-based components into nanoscale applications will enable additional degrees of freedom in manipulating with spin and charge not easily attainable otherwise. Multiferroic bismuth ferrite lead titanate has been chemically synthesized in form of nanocrystalline films. The morphology of the films revealed a single perovskite phase confined within crystalline grains of few tens of nm in size. The films were found to exhibit ferroelectricity and ferromagnetism with characteristic electric polarization and magnetization hysteresis loops, transformations associated with spin reorientation in an external magnetic field and the spin-glassy behavior well above the room temperature. High degree of magnetic frustration and disorder in the spin system spatially confined in the nanograins, distribution of the grains anisotropy axis, inter-grain interactions, and the effects of uncompensated spins on the large effective surface/interface favored by the nanocrystalline morphology were assumed to be responsible for the anomalous magnetic properties and glassy dynamics in the films.  相似文献   
103.
Surface-enhanced Raman scattering (SERS) active substrates were made via liquid flame spray deposition and inkjet printing of silver nanoparticles. Both processes are suitable for cost-effective fabrication of large-area SERS substrates. Crystal violet (CV) solutions were used as target molecules and in both samples the detection limit was approximately 10 nM. In addition, sintering temperature of the inkjet printed silver nanoparticles was found to have a large effect on the SERS activity with the higher curing temperature of 200 °C resulting in contamination layer on silver and cancelation of the SERS signal. This layer was characterized using an X-ray photoelectron spectroscopy (XPS).  相似文献   
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The elastic cross section for proton proton scattering at 11.75 GeV/c was measured at the Argonne ZGS using a 50% polarized target. In the range p2=0.6 → 2.2 (GeV/c)2 we obtained precise measurements of dσdt(ij) for the ? ?, and ? initial spin states perpendicular to the scattering plane. We confirmed that the asymmetry parameter, A, decreases with energy in the diffraction peak, but is approximately energy-independent at large p2. We found that the spin correlation parameter cnn acquires rather dramatic structure, and at large p2 seems to grow with energy.  相似文献   
106.

Background  

In the CNS, the heterotrimeric G protein Gαi2 is a minor Gα subunit with restricted localization in the ventricular regions including the ependymal cilia. The localization of Gαi2 is conserved in cilia of different tissues, suggesting a particular role in ciliary function. Although studies with Gαi2-knockout mice have provided information on the role of this Gα subunit in peripheral tissues, its role in the CNS is largely unknown. We used intracerebroventricular (icv) antisense administration to clarify the physiological role of Gαi2 in the ventricular system.  相似文献   
107.
Molybdenum forms a range of oxides with different stoichiometries and crystal structures, which lead to different properties and performance in diverse applications. Herein, crystalline molybdenum oxide thin films with controlled phase composition are deposited by atomic layer deposition. The MoO2(thd)2 and O3 as precursors enable well-controlled growth of uniform and conformal films at 200–275 °C. The as-deposited films are rough and, in most cases, consist of a mixture of α- and β-MoO3 as well as an unidentified suboxide MoOx (2.75 ≤ x ≤ 2.89) phase. The phase composition can be tuned by changing deposition conditions. The film stoichiometry is close to MoO3 and the films are relatively pure, the main impurity being hydrogen (2–7 at-%), with ≤1 at-% of carbon and nitrogen. Post-deposition annealing is studied in situ by high-temperature X-ray diffraction in air, O2, N2, and forming gas (10% H2/90% N2) atmospheres. Phase-pure films of MoO2 and α-MoO3 are obtained by annealing at 450 °C in forming gas and O2, respectively. The ability to tailor the phase composition of MoOx films deposited by scalable atomic layer deposition method represents an important step towards various applications of molybdenum oxides.  相似文献   
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Chemical standards for positive ion mode electrospray ionization ion mobility spectrometry/mass spectrometry (ESI(+)-IMS/MS) are suggested. The low clustering tendency of tetraalkylammonium halides makes them ideal chemical standards for ESI(+)-IMS/MS. A homologous series of these compounds forms a useful external standard for instrument testing and resolution calibration of an IMS instrument. Selected homologues or a mixture of tetraalkylammonium halides can be used as mobility standards in the analytical runs. Absolute and relative reduced mobilities were calculated for C2--C8, C10 and C12 tetraalkylammonium halides. Absolute reduced mobilities in nitrogen were 1.88, 1.56, 1.33, 1.15, 1.02, 0.92, 0.84, 0.73, and 0.67 cm2 V(-1) s(-1), for C2--C8, C10 and C12 tetraalkylammonium halides, respectively. Relative reduced mobilities (relative to 2,6-di-tert-butylpyridine) for the same compounds were 1.20, 1.00, 0.855, 0.743, 0.658, 0.59, 0.54, 0.47, and 0.43, respectively.  相似文献   
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