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P. MORLIÉRE M. BAZIN L. DUBERTRET R. SANTUS T. SA E. MELO G. HÜPPE J. HAIGLE P. FORLOT A. BERNARD 《Photochemistry and photobiology》1991,53(1):13-19
5-Geranoxypsoralen, commonly called bergamottin, a major furocoumarin contained in bergamot oil, is reported in vitro as a highly photoreactive psoralen. In ethanol, it exhibits quite a high triplet state quantum yield (approximately 0.37). The triplet state is involved in subsequent photochemistry which depends on the initial concentration and on the presence of oxygen. In contrast to most psoralens, absorption and fluorescence data suggest that 5-geranoxypsoralen does not interact with DNA in the dark. No UVA-induced interstrand cross-links in DNA were shown. 相似文献
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研究了用酸分解试样后不需分离基体直接用电感耦合等离子体原子发射光谱(ICP-AES)法测定铅锭中银、铜、铋、砷、锑、锡、锌、铁、镉、镍、铊11种杂质元素的方法。优化了样品前处理条件及仪器检测条件。方法的检出限为0.0012~0.0168μg/mL,回收率为89%~110%,RSD为2.3%~5.0%。方法简便快速,检出限低,精密度和准确度能满足铅锭中杂质元素的检测要求,具有较强的实用性和可操作性,可用于铅锭中杂质元素的测定。 相似文献
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Leaf G Kaper H Yan M Novosad V Vavassori P Camley RE Grimsditch M 《Physical review letters》2006,96(1):017201
We investigate stripe domain formation in nanometer sized Co bars. The magnetic equilibrium states and the magnetic spin wave frequencies are obtained from micromagnetic-like simulations. We find that the lowest frequency standing-wave mode has the same spatial structure as the stripe domains at remanence and it goes soft at the field where the stripe domains emerge. We show, therefore, that the final domain structure at remanence, which is not the configuration with lowest energy, is predicted from a high-field analysis of the frequencies of the standing spin waves. 相似文献
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ER Badman GE Patterson JM Wells RE Santini RG Cooks 《Journal of mass spectrometry : JMS》1999,34(8):889-894
Dual-detector differential non-destructive Fourier transform detection in a quadrupole ion trap is shown to improve signal intensity and reduce noise compared with spectra recorded using a single detector. A larger area detector in each end-cap electrode is machined to fit its hyperbolic shape and so minimize field imperfections on the z-axis. Argon, acetophenone and bromobenzene spectra were recorded to allow a comparison between single- and dual-detector (differential) modes of detection and to demonstrate the improvement achieved with differential detection. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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Newell MK Melamede R Villalobos-Menuey E Swartzendruber D Trauger R Camley RE Crisp W 《Journal of immune based therapies and vaccines》2004,2(1):3
A widely held view is that oncolytic agents induce death of tumor cells directly. In this report we review and discuss the
apoptosis-inducing effects of chemotherapeutics, the effects of chemotherapeutics on metabolic function, and the consequent
effects of metabolic function on immune recognition. Finally, we propose that effective chemotherapeutic and/or apoptosis-inducing
agents, at concentrations that can be achieved physiologically, do not kill tumor cells directly. Rather, we suggest that effective oncolytic agents sensitize immunologically altered tumor cells
to immune recognition and immune-directed cell death. 相似文献
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Multidimensional residual distribution schemes for the convection–diffusion equation are described. Compact upwind cell vertex schemes are used for the discretization of the convective term. For the diffusive term, two approaches are compared: the classical finite element Galerkin formulation, which preserves the compactness of the stencil used for the convective part, and various residual-based approaches in which the diffusive term, evaluated after a reconstruction step, is upwinded along with the convective term. 相似文献
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Leszek Malkinski Nicholas Cramer Andrew Hutchison Robert Camley Zbigniew Celinski Danuta Skrzypek Ron B. Goldfarb 《Journal of magnetism and magnetic materials》2002,240(1-3):261-263
A new type of ferromagnet/antiferromagnet structure (Fe/KCoF3) was deposited by molecular beam epitaxy. Unidirectional and uniaxial anisotropies of 5.1 and 3.4 kA/m were measured at 23 K using ferromagnetic resonance. Magnetization measurements at 5 K showed a hysteresis loop shift of 6 kA/m due to exchange bias. Significant enhancement of four-fold anisotropy was found at low temperatures in the samples with polycrystalline KCoF3 structure. 相似文献