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91.
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用光纤延时自差法测量二极管激光纵向泵浦单频运转的Nd:YVO4激光器的线宽。在1秒时间内,激光线宽为25kHz。还测量了线宽与激光器腔长和输出功率的关系。 相似文献
94.
以右旋肌醇甲醚为原料,经保护的甲烷磺酸酯与腺嘌呤缩合,合成了腺嘌呤核苷类似物5.此外,化合物3经酸水解,再经环氧化高产率地合成了重要的中间体7,腺嘌呤在强有机碱存在下,对环氧化合物7进行区域性的开环反应,合成了另外两种腺嘌呤核苷类似物8和9. 相似文献
95.
Based on the generalized pulse spectrum technique that was previously developed for time-domain diffuse optical tomography, we propose a linear framework of time-domain fluorescence molecular tomography for simultaneous reconstruction of both the yield and lifetime of multi-fluorophores. The methodology is exemplified for mono-component case and validated with simulated data. 相似文献
96.
David Kenning Iztok Golobič Huijuan Xing Matej Bašelj Vito Lojk Jost von Hardenberg 《Heat and Mass Transfer》2006,42(6):511-527
Correlations for nucleate boiling heat transfer should be improved, or in the long term possibly be replaced, by the development
of mechanistic simulations that include the non-uniform spacing and variable characteristics of the nucleation sites and non-linear
interactions between the sites. This paper discusses the interactions that should be included in simulations and some lessons
from a first attempt to validate a particular simulation against experimental spatio-temporal data for wall temperature. Input
data for nucleation site positions and characteristics are a particular problem and the prospects for obtaining this data
from measurements that are independent of boiling are discussed. 相似文献
97.
We investigated the effect of photodynamic therapy (PDT) with hematoporphyrin monomethyl ether (HMME) on the viability of Streptococcus mutans (S. mutans) cells on biofilms in vitro. Streptococcus mutans is the primary etiological agent of human dental caries. Since dental caries are localized infections, such plaque-related diseases would be well suited to PDT. The diode laser used in this study had the wavelength of 635 nm, whose output power was 10 mW and the energy density was 12.74 J/cm2. HMME was used as photosensitizer. Samples were prepared and divided into five groups: (1) HMME; (2) Laser; (3) HMME Laser; (4) Control group ( ) with chlorhexidine; and (5) Control group (-) with sterile physiological saline. Inoculum of S. mutans incubated with HMME also examined with fluorescence microscopy. PDT exhibited a significantly (P < 0.05) increased antimicrobial potential compared with 20 μm/mL HMME only, laser only, 0.05% chlorhexidine, and 0.9% sterile physiological saline, which reduced the S. mutans of the biofilm most effectively. Laser and 0.05% chlorhexidine were caused reduction in the viable counts of S. mutans significantly different (P < 0.05) also, but these two test treatments did not statistically differ from each other. HMME group did not statistically differ with negative control group. Fluorescence microscopy indicated that HMME localized primarily in the S. mutans of the biofilm. It was demonstrated that HMME-mediated PDT was efficient at killing S. mutans of biofilms and a useful approach in the treatment of dental plaque-related diseases. 相似文献
98.
[AlO4Al12(OH)24(H2O)12] + (Al13) formation in electrolysis process is studied. The results detected by27Al NMR spectroscopy show that high content of Al13 polymer is formed in the partially hydrolyzed aluminum solution prepared by controlled electrolysis process. In the produced electrolyte of total Al concentration ([AlT]) 2.0 mol · L-1 with a basicity (B = OH/Al molar ratios) of 2.0, the content of Al13 polymer is over 60% of total Al. Dynamic light scattering shows that the size distribution of the final electrolyte solutions ([AlT] = 2.0 mol · L-1) is trimodal with B = 2.0 and bimodal with B = 2.5. The aggregates of Al13 complexes increase the particle size of partially hydrolyzed aluminum solution. 相似文献
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This paper is concerned with the removability of isolated singularities for the weighted p‐Laplacian with singular convection. Critical singular exponents included in diffusion and convection are exactly determined. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献