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401.
I.J. Sola V. Collados L. Plaja C. Méndez J. San Román C. Ruiz I. Arias A. Villamarín J. Atencia M. Quintanilla L. Roso 《Applied physics. B, Lasers and optics》2008,91(1):115-118
An experimental method for the production of high power optical vortices by using volume phase holographic plates is presented.
Experiments in air, N2 and Ar have been performed as an example of the method’s potential, observing non-linear effects and filamentation. Theoretical
calculations support the conclusions.
PACS 42.40.Eq; 42.65.Hw 相似文献
402.
ABSTRACTHydrochars obtained via hydrothermal carbonisation of pistachio shells are both a sustainable and an efficient alternative to commercial activated carbons for the removal of micro-pollutants from wastewaters that are difficult to handle by conventional treatments. Here a combined experimental and molecular simulation approach is adopted for the study of the caffeine/hydrochars aqueous systems. This case study serves to tune a general framework for the rational customisation of surface functional groups on hydrochars for the selective adsorption of micro-pollutants from wastewaters. Caffeine’s solubility, self-diffusion and adsorption results from aqueous solutions at relevant conditions are presented. Insights about the role of surface functional groups over the caffeine adsorption mechanism into hydrochars are gained and discussed. 相似文献
403.
We have studied photoluminescence of α-MnSe in the antiferromagnetic and paramagnetic phases. Two broad, possibly multi-component emission bands centred at about 1.53 and 1.66 eV are observed at 20 K. The frequencies and intensities of these bands show step-like shift in the vicinity of TN. On the basis of difference in peak energies at T=1.8 K and TN the d-p-d superexchange interaction in excited state is estimated to be J2g(exc)=0.918 meV. 相似文献
404.
The properties and analytical possibilities of 1,4-cyclohexanedione bisthiosemicarbazone as reagent for the spectrophotometric determination of copper have been examined. Two procedures for the estimation of copper have been established. 相似文献
405.
H.A. Meinema C.J.R.Crispim Romão J.G. Noltes 《Journal of organometallic chemistry》1973,55(1):139-141
Some new heterocyclic chlorostibines have been prepared by treatment of the corresponding dimethyltin(IV) heterocycles with antimony trichloride. 相似文献
406.
In this work, a sub-minute and sensitive capillary electrophoresis with laser-induced fluorescence (CE-LIF) method was developed for the analysis and quantitation of the neurotransmitter 5-hydroxytryptamine (5-HT) or serotonin in urine. The method involves precolumn derivatization with fluorescein isothiocyanate isomer I (FITC) using an excitation light from an argon ion laser of 488 nm and a 520 nm band pass emission filter. Different variables that affect derivatization (pH, FITC concentration, reaction time and temperature) and separation (buffer concentration, pH, applied voltage and injection time) were studied. The linear dynamic range obtained was between 0 and 188 nM with a detection limit of 16 nm with a RSD between 2 and 9%. The applicability of the proposed method was demonstrated by analysis of 5-HT in human urine, establishing a concentration of 57 nM in control urine. The method was validated by standard-addition methodology. 相似文献
407.
Christopher?Altman Jaroslaw?Pykacz Romàn?R.?ZapatrinEmail author 《International Journal of Theoretical Physics》2004,43(12):2435-2445
We introduce superposition-based quantum networks composed of (i) the classical perceptron model of multilayered, feedforward neural networks and (ii) the algebraic model of evolving reticular quantum structures as described in quantum gravity. The main feature of this model is moving from particular neural topologies to a quantum metastructure which embodies many differing topological patterns. Using quantum parallelism, training is possible on superpositions of different network topologies. As a result, not only classical transition functions, but also topology becomes a subject of training. The main feature of our model is that particular neural networks, with different topologies, are quantum states. We consider high-dimensionaldissipative quantum structures as candidates for implementation of the model. 相似文献
408.
Rom T Best T Mandel O Widera A Greiner M Hänsch TW Bloch I 《Physical review letters》2004,93(7):073002
We demonstrate quantum control over both internal and external quantum degrees of freedom in a high number of identical "chemical reactions," carried out in an array of microtraps in a 3D optical lattice. Starting from a Mott insulating phase of an ultracold atomic quantum gas, we use two-photon Raman transitions to create molecules on lattice sites occupied by two atoms. In the atom-molecule conversion process, we can control both the internal rovibronic and external center of mass quantum state of the molecules. The lattice isolates the microscopic chemical reactions from each other, thereby allowing photoassociation spectra without collisional broadening even at high densities of up to 2 x 10(15) cm(-3). 相似文献
409.
Let Q be an idempotent and right-sided quantale. There is a one to one correspondence between quantifiers and non-commutative binary
operations making Q an idempotent and right-sided quantale. If Q is an atomic and irreducible orthomodular lattice there are only two such operations. Namely, the discrete quantifier and
the indiscrete quantifer.
PACS: 0210.Ab, 0210.De
This work is dedicated to Alberto Román. 相似文献
410.
Let L be a complete orthomodular lattice. There is a one to one correspondence between complete Boolean subalgebras of L contained in the center of L and endomorphisms j of L satisfying the Borceux–van den Bossche conditions.
This article is dedicated to Raquel Hernández.
SUBJCLASS: 0210.Ab, 0210.De, 03.65.-ca 相似文献