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排序方式: 共有2459条查询结果,搜索用时 31 毫秒
991.
Xing Zhu Gui-Song Huang He-Tian Zhou Xiao Yang Zhe Wang Yong Ling Yuan-Dong Dai Zi-Zhao Gan 《Optical Review》1997,4(1):236-239
We have developed a novel sample-tip regulation for a near-field optical microscope: an ultrasonic resonance regulation method. The regulation range is from 0 to 50 nm. It shows not only stability, simplicity in construction, but also versatility in vacuum, magnetic field, and low temperature environments. The main advantage of this technique is that it is a non-optical detecting scheme, which is very important for near-field spectroscopy. Such construction can also be used as a force microscope to study the topography of insulating samples. The laser light induced force interaction in the near-field range has been observed for the first time, showing that aided by laser radiation, the shear force between sample and tip can be changed depending on the type of sample. This can be interpreted as the light induced optical tip-sample interaction of light pressure effect. The van der Waals dispersion energy and the optical binding energy induced by laser beam between dielectric tip and samples play important role. The effect confirms a theoretical prediction. This new technique and phenomenon will add new aspects to near-field optics. 相似文献
992.
993.
使用全面搜索和优化处理相结合的方法,由一组余震的P波初动解资料可以推断出余震区的构造应力的主轴方向,应力主值的相对大小(1),并同时确定了余震的两个P波节面中的断层面。对1976年唐山地震相1966年邢台地震的余震资料的计算处理,都给出了余震区的主压应力为水平东西向,主张应力为近水平南北向的结果。因此可以认为,本方法对于用地震资料研究应力场是一个有用的工具。 相似文献
994.
Brandenburg G Cinabro D Liu T Saulnier M Wilson R Yamamoto H Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Palmer M Selen M Thaler JJ Edwards KW McLean KW Ogg M Bellerive A Britton DI Hyatt ER Janicek R MacFarlane DB Patel PM Spaan B Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kotov S Kravchenko I Kwak N Kubota Y Lattery M Momayezi M Nelson JK Patton S Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Ling Z Mahmood AH O'Neill JJ Severini H Sun CR 《Physical review letters》1995,75(21):3804-3808
995.
Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Johnson E Karliner I Palmer M Selen M Thaler JJ Edwards KW Bellerive A Britton DI Janicek R MacFarlane DB McLean KW Patel PM Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Darling C Davis R Hancock N Kotov S Kravchenko I Kwak N Anderson S Kubota Y Lattery M O'Neill JJ Patton S Poling R Riehle T Smith A Savinov V Alam MS Athar SB Ling Z Mahmood AH Severini H Timm S Wappler F Anastassov A Blinov S Duboscq JE Fulton R Fujino D Gan KK 《Physical review letters》1996,77(22):4503-4507
996.
Study on the Phase Behavior of Supercritical CO2/Dynol—604/Water System and Solubilization of Methyl Orange in the Microemulsions 总被引:1,自引:0,他引:1
It was found that Dynol-604, a non-fluorous and no silicon-containing nonionic surfactant,was soluble in supercritical (SC) CO2. The phase behavior of SC CO2/Dynol-604/water system was studies. The results showed that one-phase water-in-CO2 microemulsions could be fromed. The solubilization of methyl orange in the microemulsions proved further the existence of water domain in the microemulsions. 相似文献
997.
JinLingCHAI ShouQingWANG GanZuoLI QingXU YanHongGAO 《中国化学快报》2004,15(6):699-702
A novel kinetic mechanism of esterification reaction of 1-hexanoic acid with 1-butanol,catalyzed by lipase, was studied in water-in-oil microemulsions. The microemulsions were formed by alkyl polyglucoside C10G1.54/1-butanol/cyclohexane/phosphate buffer solution. The restult shows that when the ratio of mol concentration of 1-butanol to 1-hexanoic acid is about 3.0,the initial rate V0 get the maximum values. This phenomenon was explained by the modified fishlike phase diagrams. 相似文献
998.
Natural products that act as highly specific, small-molecule protein-binding agents and as modulators of protein-protein interactions are highly complex and exhibit functional groups with three-dimensional and stereochemical diversity. The complex three-dimensional display of chiral functional groups appears to be crucial for exhibiting specificity in protein binding and in differentiating between closely related proteins. The development of methods that allow a high-throughput access to three-dimensional, skelatally complex, polycyclic compounds having few asymmetric diversity sites is essential and a highly challenging task. In the postgenomic chemical biology age, in which there is a great desire to understand protein-protein interactions and to dissect protein networking-based signaling pathways by small molecules, the need for developing "stereocontrolled, diversity-oriented synthesis" methods to generate natural product-like libraries is of utmost importance. 相似文献
999.
The medium-chain-length polyhydroxyalkanoate (PHAMCL) produced by Pseudomonas putida PGA1 using saponified palm kernel oil as the carbon source could degrade readily in water taken from Kayu Ara River in Selangor,
Malaysia. A weight loss of 71.3% of the PHA film occurred in 86 d. The pH of the river water medium fell from 7.5 (at d 0)
to 4.7 (at d 86), and there was a net release of CO2. In sterilized river water, the PHA film also lost weight and the pH of the water fell, but to lesser extents. The C8 monomer
of the PHA was completely removed after 6 d of immersion in the river water, while the proportions of the other monomers (C10,
C12, and C14) were reversed from that of the undegraded PHA. By contrast, the monomer composition of the PHA immersed in sterilized
river water did not change significantly from that of the undegraded PHA. Scanning electron microscopy showed physical signs
of degradation on the PHA film immersed in the river water, but the film immersed in sterilized river water was relatively
unblemished. The results thus indicate that the PHAMCL was degraded in tropical river water by biologic as well as nonbiologic means. A significant finding is that shorter-chain
monomers were selectively removed throughout the entire PHA molecule, and this suggests enzymatic action. 相似文献
1000.
The (0001) surface of alpha-Al(2)O(3) single crystals has been imaged by atomic force microscopy in water. The observed hexagonal lattice arrangement has a period of 4.7 A, in good agreement with the known bulk unit cell. The sample cleaning procedure was found to be crucial in obtaining clean terraces and achieving lattice resolution. 相似文献