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991.
We report a new class of ruthenium(II) polypyridine complexes functionalized with a nitrone group as phosphorogenic bioorthogonal probes. These complexes were very weakly emissive owing to rapid C=N isomerization of the nitrone moiety, but exhibited significant emission enhancement upon strain‐promoted alkyne–nitrone cycloaddition (SPANC) reaction with bicyclo[6.1.0]nonyne (BCN)‐modified substrates. The modification of nitrone with a dicationic ruthenium(II) polypyridine unit at the α‐C‐position and a phenyl ring at the N‐position led to remarkably accelerated reaction kinetics, which are substantially greater (up to ≈278 fold) than those of other acyclic nitrone–BCN systems. Interestingly, the complexes achieved specific cell membrane/cytosol staining upon specific labeling of an exogenous substrate, BCN‐modified decane (BCN‐C10), in live cells. Importantly, the in situ generation of the more lipophilic isoxazoline adduct in the cytoplasm resulted in increased cytotoxicity, highlighting a novel approach to apply the SPANC labeling technique in drug activation.  相似文献   
992.
The design, fabrication, and analytical use of a poly(methylmethacrylate) (PMMA)-based microfluidic module for nanoelectrospray ionization-tandem mass spectrometry (nano-ESI-MS/MS) were described. The microfluidic module can be mass-produced at low costs and used as a disposable device to generate nano-ESI-MS/MS signals for protein identification from low amounts of protein samples. Compared with commercially available nanospray capillary tips, the module gave comparable signal quality and also offered advantages in convenience and easiness of operation, permitting repeated usage, and disposability.  相似文献   
993.
A whole impulsive control scheme of nonlinear systems with time-varying delays, which is an extension for impulsive control of nonlinear systems without time delay, is presented in this paper. Utilizing the Lyapunov functions and the impulsive-type comparison principles, we establish a series of different conditions under which impulsively controlled nonlinear systems with time-varying delays are asymptotically stable. Then we estimate upper bounds of impulse interval and time-varying delays for asymptotically stable control. Finally a numerical example is given to illustrate the effectiveness of the method.  相似文献   
994.
刘峰  关治洪  王华 《中国物理 B》2008,17(7):2405-2411
We propose an impulsive hybrid control method to control the period-doubling bifurcations and stabilize unstable periodic orbits embedded in a chaotic attractor of a small-world network. Simulation results show that the bifurcations can be delayed or completely eliminated. A periodic orbit of the system can be controlled to any desired periodic orbit by using this method.  相似文献   
995.
This paper proposes an experimentally feasible scheme for implementing quantum dense coding of trapped-ion system in decoherence-free states. As the phase changes due to time evolution of components with different eigenenergies of quantum superposition are completely frozen, quantum dense coding based on this model would be perfect. The scheme is insensitive to heating of vibrational mode and Bell states can be exactly distinguished via detecting the ionic state.  相似文献   
996.
This paper deals with the exponential stability of impulsive Takagi-Sugeno fuzzy systems with delay. Impulsive control and delayed fuzzy control are applied to the system, and the criterion on exponential stability expressed in terms of linear matrix inequalities (LMIs) is presented.  相似文献   
997.
The seasonal variability of cloud optical depth over northwestern China derived from Clouds and the Earth's Radiant Energy System (CERES) Single Scanner Footprint (SSF) Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) Edition IB data from July 2002 to June 2004 is presented. The regions of interest are those with Asia monsoon influence, the Tianshan and Qilian Mountains, and the Taklimakan Desert. The results show that the instantaneous measurements presented here are much higher than the previous results derived from International Satellite Cloud Climatology Project (ISCCP) D2 monthly mean data. Generally the measurements of cloud optical depth are the highest in summer and the lowest in winter, however, Taklimakan Desert has the lowest measurements in autumn. The regional variation is quite significant over northwestern China.  相似文献   
998.
372-mJ long pulse pyrotechnically pumped laser   总被引:2,自引:0,他引:2  
A pyrotechnically pumped Nd glass laser is demonstrated by the use of pyrotechnic flashlamps composed of several chemical materials arranged in a stable plane concave resonator cavity. The flashlamp was made of chemical mixture with oxidant, fuel, and binder. The emission spectrum of pyrotechnic flame covered most of the absorption bands of Nda+ in phosphate glass. Under 4.56-g chemical mixture pumping, long pulse output power of about 5.5 W was achieved.  相似文献   
999.
Let β > 1 be a Pisot number andg be a positive Hölder continuous function with period one and g(0) = 1. The multiperiodic functionG(ξ)=Π n=0 g(ξ/βn) is studied and the asymptotic behaviour ofI G(T) = ∫ 0 T G(ξ)dξ investigated. We prove that the limit of logI(T)/ logT exists asT tends to infinity. We also provide a method to calculate this limit for the caseg(ξ) = cos2 2πξ, corresponding to the Fourier transform of the Bernoulli convolution associated to the golden number (or some of its generalizations).  相似文献   
1000.
An adaptive trust region method and its convergence   总被引:17,自引:0,他引:17  
In this paper, a new trust region subproblem is proposed. The trust radius in the new subproblem adjusts itself adaptively. As a result, an adaptive trust region method is constructed based on the new trust region subproblem. The local and global convergence results of the adaptive trust region method are proved. Numerical results indicate that the new method is very efficient.  相似文献   
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