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351.
A theoretical scheme for preserving the entanglement in a two-qubit-spin coupled system in the presence of Dzyaloshinskii–Moriya (DM) anisotropic antisymmetric interaction is proposed. On the basis of a sequence of operations performed periodically on the system, the scheme can preserve the entanglement of the system starting from any initial state with any desired high precision for any desired long duration.  相似文献   
352.
In this paper uniform persistence is establised for kolmogorov type Prey‐Predator and competion models with per capitals ent growth rates that are dependent on time‐lagged population densities.  相似文献   
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Zou  Fan  Zuo  Jing  Geng  Chao  Li  Feng  Huang  Guan  Liu  Jiaying  Jiang  Jiali  Fan  Zhihua  Li  Xinyang 《Journal of Russian Laser Research》2021,42(4):462-467
Journal of Russian Laser Research - Laser aiming is one of the key technologies of laser atmospheric transmission. The beam actually is affected by atmospheric turbulence and mechanical vibration;...  相似文献   
355.
A novel approach was developed to improve the solubility of non-soluble compounds by introducing solubilising molecules peripherally through hydrogen-bond-mediated assembly. The solubilisation process can be reversed by adding competing hydrogen bonding moieties and removing the solubilising molecules. This method may potentially facilitate device fabrication.  相似文献   
356.
The fabrication of three‐dimensional (3D) electrospun composite scaffolds was presented in this study. Layers of electrospun meshes made from composites of poly(lactide‐co‐glycolide acid) (PLGA) and hydroxyapatite (HA) were stacked and sintered using pressurized gas. Three HA concentrations of 5, 10, and 20 wt % were tested, and the addition of the HA nanoparticles decreased the tensile mechanical properties of the meshes with 20 wt % HA. However, after the gas absorption process, the fibers within the mesh sintered, which improved the mechanical properties more than twofold. The fabrication of 3D, porous, electrospun scaffolds was also demonstrated. The resulting 3D scaffolds had open porosity of up to 70% and modulus of ~20 MPa. This technique improves on the current electrospinning technology by overcoming the challenges of depositing a thick, 3D structure. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011  相似文献   
357.
The inclusion complexes of uniconazole [(E)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-lyl)-1-penten-3-ol, UCZ] with two cyclodextrin derivatives, hydroxypropyl-β-cyclodextrin (HP-β-CD) and methylated-β-cyclodextrin (Me-β-CD), were prepared and characterized by 1H NMR and FT-IR. The phase solubility of UCZ and HP-β-CD, UCZ and Me-β-CD, which displays the ability of CDs complexation and solubilization, was studied in aqueous solutions and phosphate buffer solutions (PBS) with different property pH values (6.2, 7.2, 8.0). The solubility results indicated that the pH of PBS showed more enhancement on the interaction of HP-β-CD and UCZ than Me-β-CD with the increasing pH value, and the optimal pH value for complexation of UCZ and HP-β-CD, UCZ and Me-β-CD was at 8.0 and at 7.2, respectively. These were also determined by UCZ release behavior and dissolution studies of the complexes in solid state.  相似文献   
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This paper proposes a data-driven stability criterion for quadratic stabilization of unknown nonlinear discrete-time systems. The novelty of this quadratic stability criterion lies in the direct use of the time series of system states, instead of using mathematical models. The data-driven stability criterion is utilized to design a control for stabilizing unknown nonlinear systems using online black-box system identification. The effectiveness and the adaptability of the proposed approach are compared with those of adaptive feedback linearization method with an example of stabilizing a nonlinear aeroelastic system.  相似文献   
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