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141.
Glaser SJ 《Angewandte Chemie (International ed. in English)》2001,40(1):147-149
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Vandersypen LM Steffen M Breyta G Yannoni CS Cleve R Chuang IL 《Physical review letters》2000,85(25):5452-5455
We report the realization of a nuclear magnetic resonance quantum computer which combines the quantum Fourier transform with exponentiated permutations, demonstrating a quantum algorithm for order finding. This algorithm has the same structure as Shor's algorithm and its speed-up over classical algorithms scales exponentially. The implementation uses a particularly well-suited five quantum bit molecule and was made possible by a new state initialization procedure and several quantum control techniques. 相似文献
143.
Steffen M Vandersypen LM Chuang IL 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2000,146(2):369-374
The rotation of a spin subject to an on-resonance soft pulse and simultaneously to a soft pulse at a nearby frequency may strongly deviate from the desired rotation expected for a single on-resonance pulse. The deviation is the result of transient frequency shifts of the spin caused by the off-resonance irradiation. We show that the resulting error can be corrected by shifting the frequency of the on-resonance pulse in such a way that it tracks the shift of the spin frequency. Experimentally, the effectiveness of this simple and intuitive method is demonstrated for simultaneous inversions at nearby frequencies in the case of both coupled and uncoupled spins. Simulations predict that the correction technique is effective for arbitrary pulse shapes and tip angles and is particularly useful when the frequency window of the shaped pulse is two to eight times the frequency separation between the chemical shifts of the two spins. 相似文献
144.
Meg Duroux Leonid Gurevich Esben Skovsen Steffen B. Petersen 《Applied Surface Science》2007,254(4):1126-1130
Ultraviolet light can be used to immobilize biomolecules onto thiol reactive surfaces in order to, e.g., make biosensors. The mechanism involves light-induced formation of free, reactive thiol groups in disulphide containing molecules. This technology allows for the creation of arrays of biomolecules with a high degree of reproducibility, circumventing the need for often expensive nano/micro-dispensing technologies. The ultimate size of the immobilized spots is defined by the focal area of the UV beam. Light-induced immobilization has the added benefit that the immobilized molecules will be spatially oriented and covalently bound to the surface. In this paper, we demonstrate the utility of a sensor array created with the new sensor technology when integrated into a microfluidic system. Protein arrays made using light-induced immobilization showed successful antigen/antibody binding in a flow cell allowing the visualisation of real time binding and enzyme activity. This new technology is ideal for the creation of protein/DNA microarrays, can replace present micro-dispensing arraying technologies and is ideal as a molecular imprinting technology. 相似文献
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Steffen König 《代数通讯》2013,41(8):2395-2401
We give in this note some new bounds on p c(G) in terms of σ c for several classes of finite groups, in particular, we prove that ρ c ≤4σ c (G) for any finite solvable group G, which improves some known results. We also pose some related open problems. 相似文献
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