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131.
We report the first observation of anti-Stokes laser-induced cooling in the Er3+:KPb2Cl5 crystal and in the Er3+:CNBZn (CdF2-CdCl2-NaF-BaF2-BaCl2-ZnF2) glass. The internal cooling efficiencies have been calculated by using photothermal deflection spectroscopy. Thermal scans acquired with an infrared thermal camera proved the bulk cooling capability of the studied samples. The implications of these results are discussed. 相似文献
132.
Some ideas coming from Multi Criteria Decision Aid are here extended to group decision. We present a logical model in order
to reflect the degree of truth of the following predicate “group G considers that option x is at least as good as y.” The proposal considers the strength of the majority using its number and the intensity of its preference, and it also acknowledges
the importance of the minorities of a certain numerical significance that manifest an intense disagreement with the predicate
of the outranking. The effects of the “majority dictatorship” are restricted. Since it considers simultaneously the strength
of the majority, the importance of unhappy minorities, and the intensity of the preference/opposition, this model exhibits
desirable qualities of the classic methods by Condorcet and Borda. This model can be used to solve problems regarding selection,
ranking, classification, and sorting. Various examples are given, which show the quality of the solutions that were obtained. 相似文献
133.
Fernandez M. Ver Hoeye S. Herran L.F. Las-Heras F. 《Microwave and Wireless Components Letters, IEEE》2008,18(5):347-349
A new optimization method is presented for the design of wide-band harmonic self-oscillating mixers (HSOMs). High conversion gain is obtained through near-bifurcation operation and optimization of the harmonic content of the self-oscillation. Bifurcation analysis- and control-techniques are used in combination with nonlinear optimization techniques based on the use of an auxiliary generator. An 11.25-1.5 GHz third harmonic self-oscillating mixer (3HSOM) with a 2.5 dB down-conversion gain over a 1.2 GHz bandwidth has been designed. A good agreement between the simulated and experimental results has been found. 相似文献
134.
Valantis Vais Milica Mrcarica Alejandro F. Braa Tony Leo Juan Manuel Fernandez 《Progress in Photovoltaics: Research and Applications》2011,19(3):280-285
This study focused on how the formation of phosphosilicate glass (PSG) film affects the solar cell emitter profile when using an inline ultrasonic mist phosphoric acid source and an inline diffusion furnace. This investigation used a novel approach, whereby the samples were extracted from the inline furnace mid‐process that allowed for the investigation of incompletely formed PSGs. All experimentation was conducted at BP Solar Australia. Total Gravimetric Analysis found that the dilute phosphoric acid dehydrates to form a high concentration phosphoric acid layer on the top surface. X‐ray photoelectron spectroscopy then showed this top surface reacts with the silicon and is reduced to form silicon phosphide. ECV results then demonstrated that the sheet resistance and emitter surface concentration of phosphorus is dependent upon the ratio of phosphide to total phosphorus in the PSG film. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
135.
136.
Carla Maria Mariano Fernandez Maurício Ferreira da Rosa Ana Claudia Aparecida Mariano Fernandez Wanessa de Campos Bortolucci Fabiana Borges Padilha Ferreira Giani Andrea Linde 《Natural product research》2020,34(5):731-735
AbstractThis study, was to evaluate the acaricidal effect of the essential oil (EO) and fractions (FR) obtained from Laurus nobilis leaves on Rhipicephalus (Boophilus) microplus. Eight fractions were obtained, however FR1: sabinene (37.83%), β-pinene (13.50%), 1,8-cineole (12.66%), α-pinene (12.56%) and FR8: α-terpineol (79.19%) were highlighted as to the larvicidal potential when submitted by Larval Packet Test. The EO was tested by the Adult Immersion Test, at concentrations of 200.00; 100.00 and 50.00?µL/mL caused mortality of engorged females, egg mass reduction and hatching inhibition. Two fractions are shown to be efficient in controlling larvae FR8 (LC50?=?0.13?µL/mL, LC99?=?0.51?µL/mL) and FR1 (LC50?=?0.20?µL/mL, LC99?=?0.56?µL/mL). The fractionation of EO was determinant to elucidate which compounds were responsible for the larvicidal potential. This study opens new perspectives to direct new bioassays with the compounds obtained in the fractionation, since they present high potential on cattle tick larvae. 相似文献
137.
Antonio Fernandez Emily J. Thompson Jeffrey W. Pollard Takanori Kitamura Marc Vendrell 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(47):17050-17054
We report the novel chemical design of fluorescent activatable chemokines as highly specific functional probes for imaging subpopulations of immune cells in live tumours. Activatable chemokines behave as AND‐gates since they emit only after receptor binding and intracellular activation, showing enhanced selectivity over existing agents. We have applied this strategy to produce mCCL2‐MAF as the first probe for in vivo detection of metastasis‐associated macrophages in a preclinical model of lung metastasis. This strategy will accelerate the preparation of new chemokine‐based probes for imaging immune cell function in tumours. 相似文献
138.
139.
Chemoselective Chromium(II)‐Catalyzed Cross‐Coupling Reactions of Dichlorinated Heteroaromatics with Functionalized Aryl Grignard Reagents 下载免费PDF全文
Dr. Andreas K. Steib Dr. Olesya M. Kuzmina Sarah Fernandez Dr. Sushant Malhotra Prof. Paul Knochel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):1961-1965
Chromium(II) chloride catalyzes the chemoselective cross‐coupling reaction of dichloropyridines with a range of functionalized (hetero)aromatic Grignard reagents at room temperature. Functional groups, such as esters and acetals, are well tolerated in this transformation. Previously challenging substrates, quinolines and isoquinolines, participate in the selective Cr‐catalyzed cross‐coupling in cyclopentyl methyl ether (CPME) as the solvent. The effective purging of Cr salts is demonstrated by using various solid supports. 相似文献
140.
Alicia Duran Jos M. Fernandez Navarro Pedro Mazon Angel Joglar 《Journal of Non》1988,100(1-3):494-500
Glass coloured coatings of MnOm---NpOq---SiO2 (M, N = Fe, Co, Ni, Mn, Cr) prepared on soda-lime-silica flat glasses by the sol-gel route using the dip-coating technique.
The optical properties of these films were investigated by spectrophotometry and the optical parameters obtained allowed the colouration mechanism acting in each case to be determined as well as a comparison to be made with the parameters on the single TMO coloured films. Colour coordinates were calculated in every case.
On the other hand coatings have been prepared consisting of two different single TMO films. The corresponding mixed coatings were compared with these double films, showing different behaviours and widening the colour spectrum of glass TMO coatings. 相似文献