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1.
An Assay for the Quantitation of Photofrin in Tissues and Fluids   总被引:1,自引:0,他引:1  
A method for determining the concentration of Photofrin in tissues and biological fluids was developed. The procedure is based on the dissolution of biological material with Solvable a commercially available tissue so-lubilizer, followed by porphyrin-specific fluorescence detection and measurement. It was found necessary to use a quadratic standard curve for the estimation of unknown Photofrin concentrations. While this method is limited to compounds that are stable in strong base, it has the advantages of being sensitive, rapid and low cost .  相似文献   
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The design of pupil phase filters that super-resolve the axial intensity distribution with controlled side-lobe peak intensity under high numerical aperture conditions can be accomplished by incorporating the theory of electromagnetic diffraction in the method of generalized projections (MGP). The MGP results are however strongly dependent on the starting conditions and the applied constraints. In this report we study this dependence by investigating different starting pupil functions and introducing modifications to the applied constraints. Methods are described and implemented to generate a systematic set of starting conditions that enable a more thorough search of the solutions space. This approach generated results for which 95% have a super-resolved central-lobe, yet only a subset of those solutions offer a satisfactory compromise between super-resolution of the central-lobe and increased intensity of the axial side-lobes. These solutions are presented and discussed in the context of specific applications.  相似文献   
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An intense, broad feature appears in both two-photon thermal lens and multiphoton ionization spectra of liquid benzene in the 2000–1800 A region. Such bands in liquids of low ionization potential are argued to be direct two-photon excitations into the conduction bands of the liquids, appearing three or more eV below the gas-phase thresholds due to strong solvation of the ionic states. An earlier assignment of the feature in liquid benzene as a transition to the 1E2g valence state seems unlikely.  相似文献   
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Simple Zeros of the Riemann Zeta-Function   总被引:1,自引:0,他引:1  
Assuming the Riemann Hypothesis, Montgomery showed by meansof his pair correlation method that at least two-thirds of thezeros of Riemann's zeta-function are simple. Later he and Taylorimproved this to 67.25 percent and, more recently, Cheer andGoldston increased the percentage to 67.2753. Here we proveby a new method that if the Riemann and Generalized LindelöofHypotheses hold, then at least 70.3704 percent of the zerosare simple and at least 84.5679 percent are distinct. Our methoduses mean value estimates for various functions defined by Dirichletseries sampled at the zeros of the Riemann zeta-function. 1991Mathematics Subject Classification: 11M26.  相似文献   
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A Gaussian orbital calculation of the orbital structure of methanol is in excellent agreement with the photoelectron values determined here. Other alco  相似文献   
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Quantum Zeno and anti-Zeno paradoxes   总被引:1,自引:0,他引:1  
SM Roy 《Pramana》2001,56(2-3):169-178
Continuous observation of a time independent projection operator is known to prevent change of state (the quantum Zeno paradox). We discuss the recent result that generic continuous measurement of time dependent projection operators will in fact ensure change of state: an anti-Zeno paradox.  相似文献   
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粉粒体两相流的电容层析成象测量   总被引:4,自引:0,他引:4  
粉粒体系统中的固相浓度分布的在线测量是十分困难的问题.电容层析成象技术是一种近年来发展起来的非侵入式快速浓度场测量技术.它不干扰流场,不受流动中颗粒浓度、加速度、不透明等因素的制约.本文讨论其测量原理、应用、近期进展、存在的主要问题及其解决的对策.  相似文献   
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