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121.
We demonstrate a high-power, narrowband pulsed source at 390 nm by two stages of frequency doubling in periodically poled MgO:LiNbO(3) and periodically poled KTiOPO(4) of an amplified, passively mode-locked fiber laser. With a frequency quadrupling efficiency of 5.5% and a 0.1 nm bandwidth, the 250 mW ultraviolet source is a suitable compact pump source for many entanglement-based quantum information processing tasks. 相似文献
122.
Dr. Paula Morales Dr. Gemma Navarro Marc Gómez-Autet Laura Redondo Prof. Dr. Javier Fernández-Ruiz Dr. Laura Pérez-Benito Dr. Arnau Cordomí Prof. Dr. Leonardo Pardo Prof. Dr. Rafael Franco Dr. Nadine Jagerovic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):15839-15842
Single chemical entities with potential to simultaneously interact with two binding sites are emerging strategies in medicinal chemistry. We have designed, synthesized and functionally characterized the first bitopic ligands for the CB2 receptor. These compounds selectively target CB2 versus CB1 receptors. Their binding mode was studied by molecular dynamic simulations and site-directed mutagenesis. 相似文献
123.
Maura Pellei Carlo Santini Giancarlo Gioia Lobbia Franco Cantalamessa Cinzia Nasuti Mariacristina Di Prinzio Rosita Gabbianelli Giancarlo Falcioni 《应用有机金属化学》2005,19(5):583-589
New organotin(IV) derivatives containing the anionic ligands bis(3,5‐dimethylpyrazol‐1‐yl)dithioacetate [LCS2]− and bis(3,5‐dimethylpyrazol‐1‐yl)acetate [LCO2]− have been synthesized from reaction between (CH3)2SnCl2 and lithium salts of the ligands. Mononuclear complexes of the type {[LCX2](CH3)2SnCl} (X = S or O) have been obtained and fully characterized by elemental analyses and FT‐IR in the solid state and by NMR (1H, 13C and 119Sn) spectroscopy, conductivity measurements and electrospray ionization mass spectrometry in solution. The acute toxicity of new organotin(IV) derivatives on rat was studied, comparing their effect with those of dimethyltin chloride (CH3)2SnCl2. The comparison of LD50 of organotin(IV) complexes and (CH3)2SnCl2 administered intraperitoneally, as a single dose, evaluated in vivo on rats, showed that toxicity decreases as follows: (CH3)2SnCl2 > LCO2 > LCS2. The effect of these organotin(IV) complexes on DNA was evaluated in vitro and in vivo on rats treated with different doses of these compounds (1/20 LD50 and 1/100 LD50). The lymphocyte DNA status was assessed by the comet assay, a rapid and sensitive single‐cell electrophoresis technique, used to detect primary DNA damage in individual cells. After 36 h from the start of treatment the two new organotin(IV) derivatives induced a significant rise in comet assay parameters, indicating an increasing presence of damaged DNA. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
124.
Fulvio Ratto Paolo Matteini Alberto Cini Sonia Centi Francesca Rossi Franco Fusi Roberto Pini 《Journal of nanoparticle research》2011,13(9):4337-4348
We investigate the photothermal conversion and transformation of gold nanoparticles with an initial dogbone shape after dispersion
in hydrated chitosan films, which is a representative model of biological tissue, and excitation by a CW diode laser for 1 min.
Gold nanodogbones are observed to undergo a distinct modification above a sharp threshold of ~11 W cm−2 and 110 °C. Surprisingly, the very same modification is achieved up to at least 36 W cm−2 and 250 °C. We use an analytical model derived from Gans theory to associate the change in color of the films with the change
in shape statistics of these gold nanoparticles. This model proves both convenient and dependable. We interpret the photothermal
transformation as a rearrangement of particles with a dogbone shape and an aspect ratio of 4.1 into rods with an aspect ratio
of 2.5, where material from the end lobes of the dogbones may relocate to the waists of the rods. In turn, additional transitions
to stable gold nanospheres may exhibit fairly slower kinetics. 相似文献
125.
Inverse opals exhibiting strong photonic effects can cooperate with luminescent materials imbedded in their voids. While this has been demonstrated for dye molecules in the past, inspection of the literature reveals only few experiments on the potential of rare earths in this context. The efforts described focus on the spectral and spatial modification of emissive properties, whereas we here pursue the study of corresponding absorption properties. However, arbitrary incorporation of the luminescent species disturbs the photonic effects, therefore, principal preparative efforts need to be conducted to preserve both, the photonic properties of the opaline hosts and the luminescence efficiency of the guests. In this paper, we describe issues regarding the morphology and efficiency of inverse opal-incorporated rare-earth fluorides and oxifluorides and present an interior coating method for efficiency improvement. In addition, we were in this context, able to demonstrate the feasibility of energy transfer from Tb3+ modified host walls to Eu3+ guest species. 相似文献
126.
In this paper we study a family of stochastic orders of random variables defined via the comparison of their percentile residual life functions. Some interpretations of these stochastic orders are given, and various properties of them are derived. The relationships to other stochastic orders are also studied. Finally, some applications in reliability theory and finance are described. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
127.
Annals of Global Analysis and Geometry - This paper studies timelike minimal surfaces in the De Sitter space $$\mathbb S^3_1(1) \subset \mathbb R^4_1$$ via a complex variable. Using complex... 相似文献
128.
Hergueta AR Figueira MJ López C Caamaño O Fernández F Rodríguez-Borges JE 《Chemical & pharmaceutical bulletin》2002,50(10):1379-1382
A new and general method is described for the synthesis, in three steps and in good overall yields, of tetrasubstituted xanthines from an easily prepared imidazole precursor. The method is especially useful for the preparation in standardized conditions of series of xanthines combining a broad variety of primary or secondary alkyl, benzyl or aryl groups at N1 and of alkyl or arylmethyl groups at N3, that are not readily available by other methods. 相似文献
129.
R. Lo Franco G. Compagno A. Messina A. Napoli 《The European physical journal. Special topics》2008,160(1):247-257
We show that the N-photon generalized binomial states of electromagnetic field may be put in a bijective mapping with the
coherent atomic states of N two-level atoms. We exploit this correspondence to simply obtain both known and new properties
of the N-photon generalized binomial states. In particular, an over-complete basis of these binomial states and an orthonormal
basis are obtained. Finally, the squeezing properties of generalized binomial state are analyzed. 相似文献
130.
We report on a novel technique to compensate for all-order polarization-mode dispersion. By means of this technique, based on a suitable combination of phase modulation and group-velocity dispersion, we compensated for as much as 60 ps of differential group delay that affected a 10-Gbit/s return-to-zero data stream. 相似文献