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81.
We describe a new and distinctive interferometry in which a probe particle scatters off a superposition of locations of a single free target particle. Probe particles scattering off a single free "mirror" (in one dimension) or a single free "slit" (in two dimensions) can "swap" interference with the superposed target states. The condition for interference is loss of orthogonality of the target states and reduces, in simple examples, to transfer of orthogonality from target to probe states. We analyze experimental parameters and conditions necessary for interference to be observed. 相似文献
82.
83.
Evgen Fadeyev Sergii Smola Olga Snurnikova Oleksandr Korovin Natalya Rusakova 《Journal of Sol-Gel Science and Technology》2013,68(3):479-487
Luminescent organic–inorganic hybrid materials containing immobilized lanthanide(III) complexes (Ln = Nd, Eu, Tb, Yb) with modified ethylenediaminetetraacetic and diethylenetriaminepentaacetic acid were synthesized by sol–gel method. Obtained hybrids exhibit 4f-luminescence in the visible (Eu(III) and Tb(III)) and IR-region (Nd(III) and Yb(III)). The influence of the hybrid matrix on the lanthanide luminescence was established and it was shown, that the location of resonance level of Eu(III) is optimal for efficient energy transfer from matrix, while in the case of Tb(III) energy transfer does not occur and Tb(III) is able to absorb energy only due to its own week f–f transitions. It was also established that the inorganic matrix leads to elimination of nonradiative energy losses and increase of 4f-luminescence lifetimes. Covalent binding of Ln(III) aminopolycarboxylates in the matrix allows to consider obtained materials as promising for creation of photo- and chemically-stable luminescent sensors. 相似文献
84.
Vanadia transport, which is a minor reaction flux in the solid state reaction between V2O5 and MoO3, was studied using chemical and neutron activation analyses and electron spectroscopy for chemical analysis. It was found
that negligible quantities of vanadia were transferred in a molybdena briquette during the reaction. Vanadia was presumably
localized in thin external layers of molybdena grains. The reaction potential difference U
r across a Pt|MoO3|V2O5|Pt cell was studied. It was shown that in this cell U
r was produced at the molybdena briquette and was due to vanadia transport. The U
r value changed with time in two stages. The reaction potential difference U
r was constant (or diminished slightly) at the first stage and dropped abruptly at the second stage. The duration of the first
stage depended on the initial thickness of the MoO3 briquette: the thicker the briquette, the longer the U
r value was nearly constant. Causes and probable mechanisms of U
r generation are discussed in different terms: chemical reaction, variation of a
O
2 at the boundary between the reaction product and initialoxides, or surface spreading of the minor (V2O5 or V9Mo6O40) diffusant. The last mechanism, which received the least study in the general case, was shown to be the most probable one
for the reaction at hand.
Electronic Publication 相似文献
85.
86.
A double perovskite Ba4(Ca2Nb2)O11 known as the oxygen-ionic and protonic conductor is modified by substitution of La atoms for Ba atoms in its composition.
Three phases with different lanthanum contents Ba4 − x
La
x
Ca2Nb2O11 + 0.5x
with x = 0.5; 1; 1.5 are studied. The temperature dependences of conductivity are measured and the thermogravimetric studies are
carried out. The thermogravimetric curves of heating are close for all three compounds, whereas their curves of cooling strongly
differ from one another. For compositions with x = 0.5 and 1.5, the dependences of conductivity on the partial oxygen pressure PO2 P_{O_2 } and the partial water vapor pressure PH2 OP_{H_2 O} are measured. The total transport numbers of ions and the transport numbers of protons are calculated. It is shown that the
slope of the logstot ( logPH2 O )Tlog\sigma _{tot} \left( {logP_{H_2 O} } \right)_T dependence reaches 1/3 in the range of medium PH2 OP_{H_2 O} under the condition of electroneutrality 2[O″
V
] = [H*
i
], which coincides with the result obtained earlier for the Ba4Ca2Nb2O11 (x = 0) composition and the solid solutions on its basis with different Ba/Ca ratios. The obtained results are compared with
the literature data describing the incorporation of water into Ba2In2O5 and BaCe0.89(Y0.2)O2.9. 相似文献
87.
Bahar S Neiman AB Jung P Kurths J Schimansky-Geier L Showalter K 《Chaos (Woodbury, N.Y.)》2011,21(4):047501
Frank Moss was a leading figure in the study of nonlinear and stochastic processes in biological systems. His work, particularly in the area of stochastic resonance, has been highly influential to the interdisciplinary scientific community. This Focus Issue pays tribute to Moss with articles that describe the most recent advances in the field he helped to create. In this Introduction, we review Moss's seminal scientific contributions and introduce the articles that make up this Focus Issue. 相似文献
88.
D’yachenko F. A. Meisner L. L. Shugurov A. R. Neiman A. A. Semin V. O. Atovullaeva A. A. 《Technical Physics》2021,66(1):46-52
Technical Physics - The physical-mechanical properties of Ti-Ni-Ta and Ti-Ni-Ta-Si surface alloys (about 1 μm thick) synthesized on TiNi substrates by the additive thin-film electron-beam... 相似文献
89.
Joshua A. Silverman Logesh Mathivathanan Evgen V. Govor Raphael G. Raptis Konstantinos Kavallieratos 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(7):935-940
The croconate dianion is a highly versatile ligand with two tautomeric forms making it useful for building large superstructures in the solid state. The single‐crystal X‐ray structures of PbII– and CdII–croconate coordination polymers, namely catena‐poly[[[diaqualead(II)]‐μ‐croconato‐κ4O1,O2:O3,O4] monohydrate], {[Pb(C5O5)(H2O)2]·H2O}n, 1 , and catena‐poly[[triaquacadmium(II)]‐μ‐croconato‐κ4O1,O2:O3,O4], [Cd(C5O5)(H2O)3]n, 2 , have been determined. Both polymers form one‐dimensional (1D) structures; 1 is a nonplanar 1D zigzag coordination polymer extended along the crystallographic b axis, whereas 2 is a planar 1D ribbon parallel to the [101] direction. In 2 , three H2O molecules are coordinated directly to the metal atom, while in 1 , only two H2O molecules are directly coordinated to the metal atom. A third interstitial H2O molecule is involved in hydrogen bonding with O atoms of the croconate ligands of an adjacent layer and other H2O molecules, resulting in stacked double layers parallel to the [105] plane. Solid‐state FT–IR and solution UV–Vis spectra also substantiate the croconate coordination. 相似文献
90.
We propose an efficient hyperentanglement source emitting photon pairs entangled in both energy and polarization. The compact electrically driven room-temperature source, based on intersubband two-photon emission from semiconductor quantum wells (QWs) exhibits pair generation rates several orders of magnitude higher than alternative conventional schemes. A theoretical formalism is derived for the calculation of photon pair generation spectra and rates. The results are presented for superlattice structures similar to quantum cascade lasers of GaAs/AlGaAs QWs emitting in the mid-IR and far-IR and for InN/AlN QW structures suitable for telecommunication wavelengths. 相似文献