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991.
992.
We present a novel approach for preparation of nanometric protein arrays, based on binding of avidin molecules to nanotemplates generated by conductive AFM lithography on robust oligo(ethylene glycol)-terminated monolayers on silicon (111) surfaces that are protein-resistant. We showed that only biotinated-BSA but not the native BSA bind to the avidin arrays and that the resulting arrays of biotinated BSA could bind avidin to form protein dots with a feature size of approximately 30 nm. This result demonstrates that the avidin array may serve as templates for preparation of nanoarrays of a wide variety of biotin-tagged proteins for studying their interactions with other protein molecules at nanoscale. 相似文献
993.
Nitrilotriacetic acid-modified magnetic nanoparticles as a general agent to bind histidine-tagged proteins 总被引:7,自引:0,他引:7
Xu C Xu K Gu H Zhong X Guo Z Zheng R Zhang X Xu B 《Journal of the American Chemical Society》2004,126(11):3392-3393
Using Nalpha,Nalpha-bis(carboxymethyl)lysine to react with FePt magnetic nanoparticles, we synthesized the FePt-NTA conjugate, which immobilizes Ni2+ ions and selectively binds to histidine-tagged proteins at concentration as low as 0.5 pM. This simple system serves as a useful alternative to existing protocols for protein separation and also acts as a versatile agent for transporting and anchoring proteins. 相似文献
994.
Xun?Gu Selcuk?Akturk Aparna?Shreenath Qiang?Cao Rick?TrebinoEmail author 《Optical Review》2004,11(3):141-152
We review the state of the art of ultrashort-light-pulse measurement using frequency-resolved-optical-gating (FROG). Recent developments have extended the state of the art considerably. FROG devices for measuring the intensity and phase of ultrashort laser pulses have become so simple that almost no alignment is required. In addition, such devices not only operate single shot, but they also yield the two most important spatio-temporal distortions, spatial chirp and pulse-front tilt. With other FROG variations, it is now possible to measure more general ultrashort light pulses (i.e., pulses much more complex than common laser pulses), with time-bandwidth products as large as several thousand and as weak as a few hundred photons, and despite other difficulties such as random absolute phase and poor spatial coherence. 相似文献
995.
Guangyi?Gu Bing?Dai Xunlei?Ding Jinlong?YangEmail author 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,29(1):27-31
Hybrid density functional calculations are performed to study the structural and electronic properties of neutral, anionic and cationic Y3O clusters. The most stable structures of these clusters are found to be triply bridging oxygen atom structures with CS symmetry. The ground states of Y3O, Y3O- and Y3O + are doublet (2A), triplet (3A) and singlet (1A), respectively. The calculated electron affinities and ionization potentials are in good agreement with the available experimental data. Time-dependent density functional theory is used to calculate the low-lying excited states. A theoretical assignment for the features in the experimental photoelectron spectra is given.Received: 5 November 2003, Published online: 20 January 2004PACS:
36.40.Mr Spectroscopy and geometrical structure of clusters - 31.15.Ew Density-functional theory - 34.50.Gb Electronic excitation and ionization of molecules; intermediate molecular states (including lifetimes, state mixing, etc.) 相似文献
996.
Lina Geng Tao Bo Huwei Liu Na Li Feng Liu Kean Li Junling Gu Ruonong Fu 《Chromatographia》2004,59(1-2):65-70
A new capillary coating of alternate -zirconium phosphate lysozyme fabricated for open-tubular electrochromatography enantioseparation. The chiral compounds D, L-tryptophan tested were enantiomerically resolved. The influences brought by experimental parameters, such as organic modifier, temperature, applied voltage and pH of running buffer on the performance of the column, were investigated. 相似文献
997.
By combining supercritical drying technique with AAO template-assisted electrodeposition, noncollapsed, vertically aligned, and free-standing nanowire arrays on a conductive Au film have been fabricated. We also demonstrate that these free-standing nanowire arrays can be feasibly used for fabricating nanowire-based electrically driven devices. 相似文献
998.
Zinc oxide quantum rods 总被引:5,自引:0,他引:5
Yin M Gu Y Kuskovsky IL Andelman T Zhu Y Neumark GF O'Brien S 《Journal of the American Chemical Society》2004,126(20):6206-6207
Nanoscale zinc oxide (ZnO) rods of diameters close to the Bohr-exciton radius ( approximately 2 nm) can be prepared from a simple acetate precursor, resulting in ligand-capped rods of ZnO, highly dispersible in nonpolar solvents. Zinc oxide, ZnO, is a wide band-gap semiconductor with applications in blue/ultraviolet (UV) optoelectronic devices and piezoelectric devices. We observe self-assembly into uniform stacks of nanorods aligned parallel to each other with respect to the long axis, and photoluminescence measurements provide evidence for one-dimensional quantum confinement. 相似文献
999.
[reaction: see text] A novel thiourea-based C2-symmetric ligand was synthesized, and its application in the palladium-catalyzed Heck and Suzuki coupling reactions of arenediazonium salts was evaluated. The reactions, which were performed at room temperature, without added base, and under aerobic conditions, produced product in 4 h with good yield. The corresponding arenediazonium salts were easily generated in one step from anilines. 相似文献
1000.
Let k be a positive integer with k?2 and let be a family of functions meromorphic on a domain D in , all of whose poles have multiplicity at least 3, and of whose zeros all have multiplicity at least k+1. Let a(z) be a function holomorphic on D, a(z)?0. Suppose that for each , f(k)(z)≠a(z) for z∈D. Then is a normal family on D. 相似文献