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431.
Ion L Morales D Pérez J Riera L Riera V Kowenicki RA McPartlin M 《Chemical communications (Cambridge, England)》2006,(1):91-93
The behavior of the compound [RuCl(cym)(H2biim)][BAr'4] (cym = eta6-para-isopropylmethylbenzene, Ar' = 3,5-bis(trifluoromethyl)phenyl), synthesized from [[RuCl(cym)]2(mu-Cl)2], H2biim and NaBAr'4, has been studied as a receptor of anions both in solution and in the solid state. 相似文献
432.
A new reaction of the efficient difluorocarbene-generating reagent trimethylsilyl fluorosulfonyldifluoroacetate (TFDA) is reported in which molecules containing an N-alkylimidazole or benzimidazole structure undergo an unexpected one-pot conversion to N-difluoromethylthioureas. [reaction: see text]. 相似文献
433.
A new methodology for the annulation of five-membered carbocyclic rings onto enones through the dearomatizing electrochemical cyclization of furans and thiophenes has been developed. 相似文献
434.
Irina Alexandra Paun Valentin Ion Antoniu Moldovan Maria Dinescu 《Applied Physics A: Materials Science & Processing》2012,106(1):197-205
We report on MAPLE deposition of thin films of PEG:PLGA blends. The films were analyzed in terms of morphology, chemical composition,
wettability, and optical constants. These properties were particularly discussed in correlation with film thickness. The film
thickness was increased by increasing the deposition rate (i.e., laser fluence). This method was effective for fluences up
to 1 J/cm2, above which the efficiency of the deposition leveled off. Moreover, with increasing fluence above 1 J/cm2, important changes in the polymeric films were noticed: the surface roughness increased abruptly (up to ∼200 nm), the polymers
lost their chemical integrity and their optical constants underwent significant changes. In addition, surface wettability
decreased considerably, water contact angle reaching ∼90°; this was attributed to increased surface roughness and to orientation
of the hydrophobic groups toward the surfaces of the films. An alternative method for obtaining thicker films was employed,
by prolonging the deposition time while maintaining a constant, relatively low, deposition rate (i.e., fluence). In this case,
the properties of the films were significantly less affected. 相似文献
435.
TL Mitran A Nicolaev GA Nemnes L Ion S Antohe 《J Phys Condens Matter》2012,24(32):326003, 1-326003, 7
Ab initio calculations are performed in the framework of density functional theory on Mn-doped boron nitride sheets, which are candidates for two-dimensional diluted magnetic semiconductors (DMSs). Each type of substitution reveals a qualitatively different magnetic behavior encompassing ferromagnetic, anti-ferromagnetic and spin glass ordering. The ability of formation of these defects is also discussed. We analyze the dependence of the exchange couplings on the distance between impurities and the typical range and distribution are extracted. Multiple-impurity configurations are considered and the results are mapped on an Ising-type Hamiltonian with higher order exchange interactions, revealing deviations from the standard two-spin models. The percolation of interacting magnetic moments is discussed and the critical concentration is determined for the underlying transition from a ferromagnetic to a super-paramagnetic state. We conclude our study by providing the optimal conditions for doping in order to obtain a ferromagnetic DMS. 相似文献
436.
We introduce a new incompatibility criterion for quantum channels based on the notion of (quantum) Fisher information. Our construction is based on a similar criterion for quantum measurements put forward by H. Zhu. We then study the power of the incompatibility criterion in different scenarios. First, we prove the first analytical conditions for the incompatibility of two Schur channels. Then, we study the incompatibility structure of a tuple of depolarizing channels, comparing the newly introduced criterion with the known results from asymmetric quantum cloning. 相似文献
437.
SHEN Ren-sheng TENG Rui LI Xiang-ping ZHANG Jin XIA Dao-cheng FAN Zhao-qi YU Yong-sen ZHANG Yu-shu DU Guo-tong .State Key Laboratory of Materials Modification by Laser Ion Electron Beams School of Physics Optoelectronic Technology Dalian University of Technology Dalian P.R.China .State Key Laboratory on Integrated Optoelectronics College of Electronic Science Engineering Jilin University Changchun 《高等学校化学研究》2008,24(5):635-639
Metal-coated fiber Bragg grating(FBG)temperature sensors were prepared via electroless nickel(EN)plating and tin electroplating methods on the surface of normal bare FBG.The surface morphologies of the metal-coated layers were observed under a metallographic microscope.The effects of pretreatment sequence,pH value of EN plating solution and current density of electroplating on the performance of the metal-coated layers were analyzed.Meanwhile, the Bragg wavelength shift induced by temperature was monitored by an optical spectrum analyzer.Sensitivity of the metal-coated FBG(MFBG)sensor was almost two times that of normal bare FBG sensor.The measuring temperature of the MFBG sensor could be up to 280℃,which was much better than that of conventional FBG sensor. 相似文献
438.
439.