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101.
Madalan AM Roesky HW Andruh M Noltemeyer M Stanica N 《Chemical communications (Cambridge, England)》2002,(15):1638-1639
A novel heterospin system, [(CuL)2Gd(TCNQ)2].TCNQ-.CH3OH.2CH3CN, is obtained by reacting the mononuclear complex, [CuL], with gadolinium(III) nitrate, followed by the substitution of the nitrato ions with anionic organic radicals. 相似文献
102.
We demonstrate generalized ellipsometry for precise measurement of the principal indices of refraction, the extinction coefficients, and the orientations of the crystal a, b, and c axes of orthorhombic absorbing materials. Stibnite (Sb(2)S(3)) single crystals cut approximately parallel to (100), (010), (001), and (313) are studied at a representative wavelength of 589 nm. The (313) surface is sufficient for retrieval of all optical constants. The expected effects of surface over-layer formation are removed numerically. We propose generalized ellipsometry as a powerful tool for measurement of anisotropic optical function spectra of biaxial materials. 相似文献
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Sinkus R Tanter M Xydeas T Catheline S Bercoff J Fink M 《Magnetic resonance imaging》2005,23(2):159-165
Elastography is a technique to assess the viscoelastic properties of tissue by measuring an acoustic wave propagating though the object. Here, the technique is applied in the course of standard MR mammography to 15 patients with different pathologies (six breast cancer cases, six fibroadenoma cases and three mastopathy cases). Low-frequency mechanical waves are coupled longitudinally into the tissue in order to obtain sufficient wave amplitude throughout the entire breast. This leads to the presence of a substantial fraction of compressional waves, which contribute to the total displacement field. It is shown theoretically that the correct evaluation of these contributions from the compressional wave is rather difficult due to the almost incompressible nature of tissue. To overcome this problem, it is proposed to apply the curl-operator to the measured displacement field in order to completely remove contributions from the compressional wave. Results from simulations and a breast phantom demonstrate the feasibility of the technique. The in vivo results show a good separation between breast cancer and benign fibroadenoma utilizing the shear modulus. Breast cancer appears on average 2.2 (P<.001) times stiffer. All breast cancer cases showed a good delineation to the surrounding breast tissue with an average elevation of a factor of 3.3 (P< 1.4 x 10(-6)). The results as obtained for the shear viscosity do not indicate to be useful for separating benign from malignant lesions. 相似文献
110.
The seeds of Clitoria fairchildiana provided a new rotenoid, 6-hydroxy-2,3,9-trimethoxy-[1]benzopyrano[3,4-b][1]benzopyran-12(6H)-one. The structural elucidation was performed using detailed analyses of H- and 13C-NMR spectra including 2DNMR spectroscopic techniques (1H-13CHETCOR) and by comparison with spectrometric data from the literature. The anti-inflammatory activity was investigated using a capillary permeability assay. 相似文献