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61.
Third-order nonlinear optical susceptibility, χ(3) of symmetrically octa-substituted metal-free phthalocyanine thin films measured by the third-harmonic generation technique are reported. The metal-free phthalocyanine has been found to show a χ(3) (−3ω; ω,ω, ω) value as large as 7.73×10−12 esu at 1.80 μm. The figure of merit, χ(3)/α, was estimated to be 4.17×1017 esu cm at 1.05 μm and 6.97×1016 esu cm at 1.65 μm. Both linear and third-order optical properties of liquid-crystalline metal-free phthalocyanines are discussed 相似文献
62.
In Vivo Endoscopic Tissue Identification by Rapid Evaporative Ionization Mass Spectrometry (REIMS)
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Dr. Julia Balog Dr. Sacheen Kumar James Alexander Ottmar Golf Dr. Juzheng Huang Tom Wiggins Nima Abbassi‐Ghadi Dr. Attila Enyedi Dr. Sandor Kacska James Kinross Prof. George B. Hanna Prof. Jeremy K. Nicholson Prof. Zoltan Takats 《Angewandte Chemie (International ed. in English)》2015,54(38):11059-11062
Gastrointestinal cancers are a leading cause of mortality, accounting for 23 % of cancer‐related deaths worldwide. In order to improve outcomes from these cancers, novel tissue characterization methods are needed to facilitate accurate diagnosis. Rapid evaporative ionization mass spectrometry (REIMS) is a technique developed for the in vivo classification of human tissue through mass spectrometric analysis of aerosols released during electrosurgical dissection. This ionization technique was further developed by utilizing surface induced dissociation and was integrated with an endoscopic polypectomy snare to allow in vivo analysis of the gastrointestinal tract. We tested the classification performance of this novel endoscopic REIMS method in vivo. It was shown to be capable of differentiating between healthy layers of the intestinal wall, cancer, and adenomatous polyps based on the REIMS fingerprint of each tissue type in vivo. 相似文献
63.
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65.
Hanna K Beurroies I Denoyel R Desplantier-Giscard D Galarneau A Di Renzo F 《Journal of colloid and interface science》2002,252(2):276-283
During the synthesis of micelle-templated silica an intermediate inorganic/organic mesostructure is obtained with an hexagonal arrangement of channels filled by surfactant molecules. The ability of such a mesostructure to solubilize organic molecules from an aqueous solution was investigated. To that end, silica/cationic surfactant mesostructures were prepared under various conditions and their stability toward surfactant release in water was first compared in order to select materials as stable as possible. Swelled mesostructures were also used. The sorption from solution of hydrophobic molecules was then studied. The affinity of the molecules for the mesostructures is directly related to their hydrophobic character as it is derived from their octanol/water partition coefficient. A cooperative effect between hydrophobic molecules and the cationic surfactant that stabilizes the surfactant inside the mesostructure was observed. Interaction energies between the solutes and the mesostructures were determined by microcalorimetry. They varied in accordance with the hydrophobic character of the molecule and, at low sorption amounts, they were of the same order of magnitude as the solubilization enthalpies in bulk micelles. When the sorption increases, the surfactant layer in the mesostructure is not allowed to swell as the free micelle does, and steric limitations in the headgroup area render sorption less favorable. 相似文献
66.
Soliton optical phase control by use of in-line filters 总被引:2,自引:0,他引:2
We address the problem of soliton phase jitter caused by fiber amplifier noise in a communication channel. An analytical expression for phase jitter is derived by use of perturbation theory. In the absence of filters the variance of the phase is found to be proportional to the cube of the propagation distance, but it increases only linearly if in-line filters are used. We verify with simulations that in-line filters maintain the phase jitter at a level that is tolerable for transoceanic links. 相似文献
67.
A new configuration of sample and r.f.-coil for spin-echo NMR is presented. The main features are a homogeneous r.f. field over the whole surface of the sample and the possibility of calibration of the r.f.- amplitude in the presence of the magnetic material. In connection with Fourier-transformation of the echo-signals this allows for better accuracy in measurements of the NMR-enhancement factor, especially in broad spectra. The method is illustrated by an experiment with amorphous CoP, a ferromagnetic metal with a very broad spectrum. 相似文献
68.
M. Convery W. L. Davis K. DelSignore T. L. Jenkins E. Kangas M. Knepley K. L. Kowalski C. C. Taylor C. H. Wang S. H. Oh W. D. Walker P. L. Colestock B. Hanna M. A. Martens J. M. Streets R. C. Ball H. R. Gustafson L. W. Jones M. J. Longo J. D. Bjorken N. Morgan C. Pruneau 《Il Nuovo Cimento C》1996,19(6):1045-1049
Summary A small experiment, ?MiniMax?, has been set up in the C0 intersection region of the Fermilab Tevatron to seek evidence for
disoriented chiral condensates and to study other forward physics phenomena. The experiment consists of a proportional wire
chamber telescope accompanied by scintillation (trigger) counters, a lead converter, and followed by an electromagnetic calorimeter.
The solid angle accepted is a cone centered at pseudorapidity (η) of 4.1 and of radius (in η-ϕ space) of about 0.6. Over 2.5
million events thus far have demonstrated the successful operation of the apparatus, however to date the analysis has not
progressed sufficiently to permit any conclusions concerning disoriented chiral condensates.
presented byL. W. Jones
Paper presented at the Special Session on very high-energy cosmic-ray interactions (superfamilies) of the XXIV International
Cosmic-Ray Conference, Rome, August 28–September 8, 1995. 相似文献
69.
Two identical prisms are combined to form an anti-resonant ring reflector, giving total reflection without the use of coatings or roof edges. When used as the total reflector in a Q-switched NdYAG laser this device has shown a damage threshold twice that of a multilayer reflector. 相似文献
70.
1-(2-Methylindole-3-acetyl)4-arylthiosemicarbazides have been prepared and were used as reagents for gravimetric and colorimetric determinations of copper, cobalt, zinc and mercury. The synthesis of the same metal complexes of these thiosemicarbazides as a potential biological derivatives was also described. 相似文献