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51.
In this work, we report the biosynthesis of CuCo2S4 nanoparticles (Bio-NPs) via hydrothermal method. The synthetized Bio-NPs-CuCo2S4 was studied as an active material of working electrode for electrochemical supercapacitor and non-enzymatic hydrazine sensor. The Bio.NPs-CuCo2S4/ITO electrode has a specific capacitance of 264 F/g at a current density of 1 A/g. Meanwhile, the electrode exhibits excellent electrochemical performances, such as an energy density of 33 Wh/Kg and a power density of 900 W/Kg. The Bio.NPs-CuCo2S4/ITO electrode for non-enzymatic hydrazine sensor exhibits a very high sensitivity of 2400 μA.mM−1.cm−2, a wide linear range from 0.001 to 1.400 mM and shows an excellent selectivity.  相似文献   
52.
Synthetic wollastonite has been used as the active phase embedded into two different silica aerogel composites. These composites are different in respect of the route used for the synthesis of the wollastonite powder. Texture and composition of both types of composite have been characterized. In addition, several factors (pH, reaction time, CO2 saturation, etc.) that could help to optimize the carbonation process at room temperature and pressure have been studied. Under the same conditions, both composites confirm previous results showing efficiencies as CO2 sequesters between 80% and 100% in only 15 min of gas flow. The textural characteristics of the aerogel, together with the grain size of the synthetic wollastonite powder, not only increase the speed of the reaction, but also inhibit the appearance of a passivating layer on the surface of the wollastonite grains attacked by the CO2. This is an outstanding feature as it insists on a cutting-edge challenge of the CO2 research: its economical availability.  相似文献   
53.
One of the main motivations for low-energy supersymmetric theories is their ability to address the hierarchy and naturalness problems in the Higgs sector of the standard model. In these theories, at least two doublets of scalar fields are required to break the electroweak symmetry and to generate the masses of the elementary particles, resulting in a rather rich Higgs spectrum. The search for the Higgs bosons of supersymmetry and the determination of their basic properties is one of the major goals of high-energy colliders and, in particular, the LHC, which will soon start operation. We review the salient features of the Higgs sector of the minimal supersymmetric standard model and of some of its extensions and summarize the prospects for probing them at the LHC and at the future ILC. In memoriam of Julius Wess, 1934–2007.  相似文献   
54.
Belhaq  Mohamed  Fahsi  Abdelhak 《Nonlinear dynamics》2010,62(4):1001-1008

Analytical approximation of heteroclinic bifurcation in a 3:1 subharmonic resonance is given in this paper. The system we consider that produces this bifurcation is a harmonically forced and self-excited nonlinear oscillator. This bifurcation mechanism, resulting from the disappearance of a stable slow flow limit cycle at the bifurcation point, gives rise to a synchronization phenomenon near the 3:1 resonance. The analytical approach used in this study is based on the collision criterion between the slow flow limit cycle and the three saddles involved in the bifurcation. The amplitudes of the 3:1 subharmonic response and of the slow flow limit cycle are approximated and the collision criterion is applied leading to an explicit analytical condition of heteroclinic connection. Numerical simulations are performed and compared to the analytical finding for validation.

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