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排序方式: 共有267条查询结果,搜索用时 31 毫秒
81.
Michael K. Henry Alexey V. Gorshkov Yaakov S. Weinstein Paola Cappellaro Joseph Emerson Nicolas Boulant Jonathan S. Hodges Chandrasekhar Ramanathan Timothy F. Havel Rudy Martinez David G. Cory 《Quantum Information Processing》2007,6(6):431-444
Incoherent noise is manifest in measurements of expectation values when the underlying ensemble evolves under a classical
distribution of unitary processes. While many incoherent processes appear decoherent, there are important differences. The
distribution functions underlying incoherent processes are either static or slowly varying with respect to control operations
and so the errors introduced by these distributions are refocusable. The observation and control of incoherence in small Hilbert
spaces is well known. Here we explore incoherence during an entangling operation, such as is relevant in quantum information
processing. As expected, it is more difficult to separate incoherence and decoherence over such processes. However, by studying
the fidelity decay under a cyclic entangling map we are able to identify distinctive experimental signatures of incoherence.
This is demonstrated both through numerical simulations and experimentally in a three qubit nuclear magnetic resonance implementation.
相似文献
82.
83.
NMR Quantum Information Processing 总被引:1,自引:0,他引:1
84.
Kim H.H. Chandrasekhar S. Burrus C.A. Jr. Bauman J. 《Solid-State Circuits, IEEE Journal of》2001,36(5):769-776
A transimpedance amplifier packaged with an InP p-i-n photodiode has been demonstrated for 10-Gb/s SONET receiver. The shunt feedback transimpedance amplifier is fabricated in 0.25-μm modular Si BiCMOS technology. The transimpedance of 55 dBΩ is achieved at a bandwidth of 9 GHz by applying shunt peaking and filter termination at the input. The optical sensitivity of -17 dBm was measured at 10 Gb/s for a bit-error rate of 10-12 相似文献
85.
86.
The accurate experimental determination of pharmaceutical compound solubilities at various temperature and pressure ranges in supercritical carbon dioxide (ScCO2) is a challenging and time‐consuming task. Therefore, prediction or correlations of solute solubilities are essential for implementation of ScCO2 technologies to pharmaceutical industries. Solubilities of 41 pharmaceutical compounds in ScCO2 are correlated by an empirical model, which is developed based on the degree of freedom analysis. Its correlating ability is compared with existing solubility models elaborated by other authors and evaluated in terms of global mean absolute relative deviation, sum of squares due to error, root mean square deviation, R2, and Adj. R2. The proposed model is found to correlate better than existing models. 相似文献
87.
K. Paramesh N. Lakshmana Reddy M.V. Shankar T. Chandrasekhar 《International Journal of Hydrogen Energy》2018,43(8):3957-3966
It is estimated that the fossil fuel reserves are going to deplete continuously due to extensive usage. In order to cope with this crisis, it is necessary to increase the efforts towards production of biofuels such as biological hydrogen (H2). It is well-known fact that the biological hydrogen is a clean and ideal energy and liberates high amount of energy per unit mass. Several groups are working for the large scale production of H2 chemically and also using photosynthetic organisms, but output is not satisfactory. The best way to achieve enhancement of H2 is through altering the photosynthetic process by applying various stress conditions or by natural selection. In the process of selection, Chlorococcum minutum was found with improved H2 output when compared to model green alga Chlamydomonas reinhardtii in a massively parallel and competitive high-throughput screen of different green algae. Both the species belongs to class chlorophyceae of green algae and live in fresh water conditions. In extent various light, pH and temperature conditions were applied and achieved the enhancement of H2 production in this species under in vitro settings. Augmented hydrogenase activity was found in Chlorococcum minutum when compared to model alga and this may be one of the reason behind improved H2 output. Hence this species may be considered as one of the best species with respect to H2 production and also this work may be useful for future renewable energy research. 相似文献
88.
Dr. Rhushikesh A. Kulkarni Chloe A. Briney Dr. Daniel R. Crooks Sarah E. Bergholtz Dr. Chandrasekhar Mushti Dr. Stephen J. Lockett Dr. Andrew N. Lane Dr. Teresa W.-M. Fan Dr. Rolf E. Swenson Dr. W. Marston Linehan Dr. Jordan L. Meier 《Chembiochem : a European journal of chemical biology》2019,20(3):360-365
Dysregulated metabolism can fuel cancer by altering the production of bioenergetic building blocks and directly stimulating oncogenic gene-expression programs. However, relatively few optical methods for the direct study of metabolites in cells exist. To address this need and facilitate new approaches to cancer treatment and diagnosis, herein we report an optimized chemical approach to detect the oncometabolite fumarate. Our strategy employs diaryl tetrazoles as cell-permeable photoinducible precursors to nitrileimines. Uncaging these species in cells and cell extracts enables them to undergo 1,3-dipolar cycloadditions with endogenous dipolarophile metabolites such as fumarate to form pyrazoline cycloadducts that can be readily detected by their intrinsic fluorescence. The ability to photolytically uncage diaryl tetrazoles provides greatly improved sensitivity relative to previous methods, and enables the facile detection of dysregulated fumarate metabolism through biochemical activity assays, intracellular imaging, and flow cytometry. Our studies showcase an intersection of bioorthogonal chemistry and metabolite reactivity that can be applied for biological profiling, imaging, and diagnostics. 相似文献
89.
Batchu Chandrasekhar 《Journal of Sulfur Chemistry》2014,35(5):538-586
This review describes the reactions of o-aminothiophenol and its derivatives as building blocks for the synthesis of polyfunctionalized benzothiazoles with pharmacological interest. Annelated benzothiazoles were prepared by a cyclocondensation reaction of o-aminothiophenol and its derivatives with carbonyl and other functionalities. In the case of carbonyl functions, this reaction takes place by a nucleophilic addition, followed by cyclization concomitant with the elimination of water. The objective of this survey is to provide a comprehensive account of the synthesis of various benzothiazole systems and their potential to develop better chemotherapeutic agents. 相似文献
90.