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161.
Kieran AL Pascu SI Jarrosson T Gunter MJ Sanders JK 《Chemical communications (Cambridge, England)》2005,(14):1842-1844
New macrocycles incorporating a porphyrin and a [small pi] electron-rich aromatic were prepared from a dynamic disulfide library. The outcome could be influenced by use of templates. 相似文献
162.
Surface Brillouin spectroscopy (SBS) has been widely used for elastic property characterization of thin films. For films thicker than 500 nm, however, the wavelength of surface acoustic wave in the frequency range available for SBS is smaller than film thickness, and the SBS measures only the Rayleigh wave of the film. The laser-SAW technique, on the other hand, measures only the low-frequency portion of the surface acoustic wave dispersion and can estimate only one elastic modulus of the film (typically Young's modulus). In this work, we have combined the two methods to determine both Young's modulus and Poisson's ratio of a diamond-like carbon (DLC) film. It was found that reasonable estimates can be obtained for the longitudinal wave velocity, shear wave velocity, and Young's modulus of the film. The Poisson's ratio, however, still has a relatively large measurement error. 相似文献
163.
164.
A. Vitturi L. Ferreira P.D. Kunz H.M. Sofia P.F. Bortignon R.A. Broglia 《Nuclear Physics A》1980,340(1):183-204
The (6Li, d) and (d, 6Li) L = 0 transitions in the mass regions are analyzed utilizing microscopic form factors. The cross sections follow the pattern given by the two-proton and two-neutron transfer cross sections. 相似文献
165.
Maria Sofia Roma 《Annali di Matematica Pura ed Applicata》1955,40(1):365-369
Sunto Si espone un metodo per la determinazione degli autovalori per difetto e se ne dà un'applicazione al calcolo delle frequenze
di una piastra.
A Mauro Picone nel suo 70mo compleanno.
Lavoro eseguito nell'Istituto Nazionale per le Appliczaioni del Calcolo. 相似文献
166.
Santo Scalia Annachiara Dozzo Sofia Magli Giuseppe Scarcella 《Photochemistry and photobiology》2020,96(5):998-1004
Tattoo colorants decompose under solar radiation and when exposed to laser light for their removal, leading to the accumulation in the dermis of toxic products. Aim of this study was to develop lipid microparticles (LMs) loaded with the colorant, Acid Red 87 (C.I. 45380) used in tattoo inks, and to investigate the effect of this system on the photostability of the colorant under simulated sunlight or laser irradiation. LMs loaded with C.I. 45380 were prepared by melt emulsification using tristearin and phosphatidylcholine as excipients. They were characterized by optical microscopy, laser diffraction, X-ray diffraction and release studies. Free C.I. 45380 and the colorant-loaded LMs were irradiated with a solar simulator or a Q-switched laser. Irradiation with a solar simulator demonstrated that photodecomposition of C.I. 45380 was markedly reduced by incorporation of the dye in the LMs, from 20.5 ± 4.6% to 1.3 ± 1.8%. Conversely, the laser-induced degradation of the colorant (30.1 ± 6.6%) was not significantly influenced by encapsulation in the LMs (the encapsulated C.I. 45380 loss was 27.4 ± 5.5%). Incorporation of C.I. 45380 in lipid microparticles enhances the photostability under sunlight of tattoo inks containing this colorant, without affecting its laser-induced degradation and hence laser removal efficiency. 相似文献
167.
168.
169.
Synthesis,characterization and self‐assembly of well‐defined linear heptablock quaterpolymers
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Christos Ntaras George Polymeropoulos George Zapsas Konstantinos Ntetsikas George Liontos Apostolos Karanastasis Dimitrios Moschovas Sofia Rangou Charlotte Stewart‐Sloan Nikos Hadjichristidis Edwin L. Thomas Apostolos Avgeropoulos 《Journal of Polymer Science.Polymer Physics》2016,54(15):1443-1449
Two well‐defined heptablock quaterpolymers of the ABCDCBA type [Α: polystyrene (PS), B: poly(butadiene) with ~90% 1,4‐microstructure (PB1,4), C: poly(isoprene) with ~55% 3,4‐microstructure (PI3,4) and D: poly(dimethylsiloxane) (PDMS)] were synthesized by combining anionic polymerization high vacuum techniques and hydrosilylation/chlorosilane chemistry. All intermediates and final products were characterized by size exclusion chromatography, membrane osmometry, and proton nuclear magnetic resonance spectroscopy. Fourier transform infrared spectroscopy was used to further verify the chemical modification reaction of the difunctional PDMS. The self‐assembly in bulk of these novel heptablock quarterpolymers, studied by transmission electron microscopy and small angle X‐ray scattering, revealed 3‐phase 4‐layer alternating lamellae morphology of PS, PB1,4, and mixed PI3,4/PDMS domains. Differential scanning calorimetry was used to further confirm the miscibility of PI3,4 and PDMS blocks. It is the first time that PDMS is the central segment in such multiblock polymers (≥3 chemically different blocks). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1443–1449 相似文献
170.
Iron complexes as potential photocatalysts for controlled radical photopolymerizations: A tool for modifications and patterning of surfaces
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Sofia Telitel Frederic Dumur Damien Campolo Julien Poly Didier Gigmes Jean Pierre Fouassier Jacques Lalevée 《Journal of polymer science. Part A, Polymer chemistry》2016,54(5):702-713
This article reports on the presumably first use of iron complexes (FeC) as potential photocatalysts for controlled radical photopolymerization reactions (CRP2). Three compounds were designed and investigated. Good linear evolutions of the molecular weight (Mn) with the conversion were observed. A comparison was provided with a reference iridium (III) complex [Ir(ppy)3 where ppy stands for 2‐phenylpyridine]. The on/off photopolymerization experiments highlight the presence of dormant species and a re‐initiation on demand upon irradiation. This unique re‐initiation property was used for the modification of surfaces (hydrophilic/hydrophobic properties) and surface patterning as well as the synthesis of a block co‐polymer (PMMA‐b‐PBA). A comparative analysis of the behavior of these iron complexes in thermally and photochemically activated polymerization was provided. The chemical mechanisms were studied by steady state photolysis, laser flash photolysis, cyclic voltammetry, luminescence quenching, and electron spin resonance experiments. A catalytic cycle was proposed with two steps: (i) the oxidation of the FeC excited state by an alkyl halide and (ii) the reduction by the oxidized form (FeC°+) by an amine or the macroradicals leading to the regeneration of the catalyst. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 702–713 相似文献