Transition Metal Chemistry - In this paper, four diiron toluene-3,4-dithiolate complexes with phosphine ligands were synthesized and characterized. Treatment of complex... 相似文献
An experimentally feasible strong coupling system between a spin ensemble and a superconducting qubit is studied. The coupling strength can be exponentially enhanced by applying the squeezing transformations to the system. By means of the two spin ensembles commonly coupled to a superconducting qubit, a set of universal nonadiabatic holonomic single‐qubit quantum gates can be realized in a decoherence‐free subspace. Furthermore, this proposal is robust with respect to decay of the system parameters, and it is experimentally feasible with currently available technology. 相似文献
In this paper, two fault tolerant authenticated quantum dialogue (AQD) protocols against the collective-dephasing noise and the collective-rotation noise are constructed, respectively, by using logical qubits and controlled-not (CNOT) operations. The proposed protocols can accomplish the mutual identity authentications between two communicants before decoding and overcome the information leakage problem. The quantum measurements throughout the proposed protocols can be simplified into the single-photon measurements. Moreover, they have the information-theoretical efficiency as high as 50%. Different from the recent fault tolerant QD protocols generating two adjacent logical qubits in the same state, the proposed protocols do not have this special requirement.
In this study, three different volume expansion ratios of expanded graphite (EG) are prepared and investigated to enhance the heat transfer efficiency of the sodium acetate trihydrate (SAT) composites. A series of SAT composite phase change materials (CPCMs) with EG were prepared. The influence of volume expansion ratio and mass fraction of EG on thermodynamic characteristics of SAT CPCMs was examined, including thermal conductivity, phase change temperature, enthalpy, latent heat storage and release time, and the degree of supercooling. Results showed that SAT CPCMs can be absorbed adequately by EG, and EG could enhance the heat transfer efficiency effectively. But it also brought some problems with the addition of all the three volume expansion ratios of EG, such as the poor enthalpy and serious supercooling. Particularly, the situation gets worse with the increase in mass and expansion ratio of EG. Therefore, it is better to choose the EG with proper expansion ratio or reduce the proportion of the EG which possesses higher expansion ratio. Besides, thermal cycling test and thermogravimetric analysis revealed that the SAT CPCMs with 3 mass% EG showed a good thermal stability.
This paper presents a semi-analytical drained solution for cylindrical cavity expansion in sand. By introducing an auxiliary variable, defined as the ratio of the original position to the current position of a material particle, the governing differential equations of the cylindrical cavity expansion problem can be transformed into a group of first-order ordinary differential equations. These equations are solved as an initial value problem by incorporating a bounding-surface model with state-dependent dilatancy. This approach does not require the division of the material around the cavity into an elastic zone and a plastic zone. The state-dependent dilatancy model employed in this study allows the investigation of the effects of the initial relative density and mean normal stress of the sand, whereas the rigorous definitions of the invariant stresses permit the examination of the effect of the initial ratio of the horizontal stress to the vertical stress. Moreover, the model parameters that are of paramount importance for the cylindrical cavity expansion analyses are determined via comprehensive parametric studies. 相似文献
A new synthetic application of N-sulfonyl-1,2,3-triazoles acting as a 1-aza-[4C] synthon via the 1,2-shift reaction of an α-imine rhodium carbene was developed for the synthesis of fused pyrimidine derivatives. The high reactivity of the strained three-membered 2H-azirine ring facilitated the unusual cyclization of electron-deficient dienes with electron-deficient dienophiles. The compatibility was good with common functionalities tolerated. Excellent chemoselectivity was observed, and no reactions occurred between the rhodium carbene and 2H-azirine. The products could be converted into seven-membered multi-functionalized 1H-1,4-diazepine derivatives, illustrating the potential application of the protocol in medium-sized N-heterocycle synthesis. 相似文献