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81.
Mingxi Yang Yang Meng Junjun Liu Weixian Yu Bai Yang 《Particle & Particle Systems Characterization》2019,36(1)
Carbon dots (CDs), as an emerging fluorescent nanomaterial with low toxicity, has been widely applied in various bio‐related fields. However, investigations on their capabilities in guiding osteogenic differentiation are rarely seen, which has great significance in osteoporosis therapy and bone regeneration. Herein, for the first time, a new kind of Mg2+‐doped CDs is facilely synthesized through a one‐step hydrothermal method from metal gluconate salts. The CDs can serve as nanocarrier of Mg2+ ions entering into cells, and the bioessential metal ions subsequently stimulate osteoblastic differentiation by improving alkaline phosphatase (ALP) activity and upregulation related mRNA expression. Noteworthy, the raw material has almost negligible performance on osteoblastic differentiation compared to Mg‐CDs, which is due to the ultrasmall sizes of CDs and the efficient uptake by cells. Moreover, benefitting from the fluorescence properties, Mg‐CDs can also be applied as cell labeling agents. This work proposes a new strategy to synthesize multifunctional metal ion‐doped CDs, which might had great potential in serving as promising nanodrugs for bone loss therapy. 相似文献
82.
Dr. Yoji Horii Dr. Keiichi Katoh Dr. Kunihisa Sugimoto Dr. Ryo Nakanishi Dr. Brian K. Breedlove Prof. Dr. Masahiro Yamashita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(12):3098-3104
In the research field of single-molecule magnets (SMMs), lanthanoid–lanthanoid interactions, so-called f–f interactions, are known to affect the SMM properties, although their magnitudes are small. In this article, an SMM with very weak f–f interactions is reported, and the effects of the interactions on the SMM properties are discussed. X-ray structural analysis of the DyIII-CdII-phthalocyaninato sextuple-decker complex (Dy2Cd3) reveals that the intramolecular Dy−Dy length in Dy2Cd3 is more than 13 Å, which is longer than the intermolecular Dy−Dy length. Even though the two DyIII ions are far apart, intermolecular ferromagnetic dipole–dipole interactions are observed in Dy2Cd3. From detailed analysis of ac magnetic susceptibilities, quantum tunneling of the magnetization (QTM) in Dy2Cd3 is partially suppressed owing to the existence of very weak Dy−Dy interactions. Our results show that even very weak Dy−Dy interactions act as a dipolar bias, suppressing QTM. 相似文献
83.
Dr. Francesca Arcudi Dana Emily Westmoreland Prof. Emily Allyn Weiss 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(63):14469-14474
Colloidal quantum dot (QD) photocatalysts have the electrochemical and optical properties to be highly effective for a range of redox reactions. QDs are proven photo-redox catalysts for a variety of reactions in organic solvents but are less prominent for aqueous reactions. Aqueous QD photocatalysts require hydrophilic ligand shells that provide long-term colloidal stability but are not so tight-binding as to prevent catalytic substrates from accessing the QD surface. Common thiolate ligands, which also poison many co-catalysts and undergo photo-oxidative desorption, are therefore often not an option. This paper describes a framework for the design of water-solubilizing ligands that are in dynamic exchange on and off the QD surface, but still provide long-term colloidal stability to CdS QDs. The binding affinity and inter-ligand electrostatic interactions of a bifunctional ligand, aminoethyl phosphonic acid (AEP), are tuned with the pH of the dispersion. The key to colloidal stability is electrostatic stabilization of the monolayer. This work demonstrates a means of mimicking the stabilizing power of a thiolate-bound ligand with a zwitterionic tail group, but without the thiolate binding group. 相似文献
84.
A linear optical unambiguous discrimination of hyperentangled Bell states is proposed for two‐photon systems entangled in both the polarization and momentum degrees of freedom (DOFs) assisted by time bin. This unambiguous discrimination scheme can completely identify 16 orthogonal hyperentangled Bell states using only linear optical elements, where the function of the auxiliary entangled Bell state is replaced by time bin. Moreover, the possibility of extending this scheme for distinguishing hyperentangled Bell states in n DOFs is discussed, and it shows that hyperentangled Bell states in n ( ) DOFs can be distinguished with k ( ) auxiliary entangled states of additional DOFs by introducing a time delay, which decreases the auxiliary entanglement resource required for unambiguous discrimination of hyperentangled Bell state. Therefore, this scheme provides a new way for distinguishing hyperentangled states with current technology, which will extend the application of discrimination of hyperentangled states via linear optics to other quantum information protocols besides hyperdense coding schemes in the future. 相似文献
85.
86.
Controlled quantum teleportation of an unknown single-qutrit state in noisy channels with memory 下载免费PDF全文
《中国物理 B》2021,30(6):60303-060303
This paper proposes a three-dimensional(3 D) controlled quantum teleportation scheme for an unknown single-qutrit state. The scheme is first introduced in an ideal environment, and its detailed implementation is described via the transformation of the quantum system. Four types of 3 D-Pauli-like noise corresponding to Weyl operators are created by Kraus operators: trit-flip, t-phase-flip, trit-phase-flip, and t-depolarizing. Then, this scheme is analyzed in terms of four types of noisy channel with memory. For each type of noise, the average fidelity is calculated as a function of memory and noise parameters, which is afterwards compared with classical fidelity. The results demonstrate that for trit-flip and t-depolarizing noises, memory will increase the average fidelity regardless of the noise parameter. However, for t-phase-flip and trit-phaseflip noises, memory may become ineffective in increasing the average fidelity above a certain noise threshold. 相似文献
87.
ABSTRACTWe study the effect of the external electric field Fext on the low-temperature electron mobility μ in an asymmetrically doped AlxGa1-xAs based V-shaped double quantum well (VDQW) structure. We show that nonlinearity of µ occurs under double subband occupancy on account of intersubband effects. The field Fext alters the VDQW potential leading to transfer of subband wave functions between the wells, which affects the scattering potentials and hence μ. In the VDQW structure, due to the alloy channel layer, the alloy disorder (Al-) scattering happens to be significant along with the ionised impurity (Imp-) scattering. The non-linear behaviour of μ is because of μImp, while the overall magnitude of μ is mostly due to μAl. The increase of difference in the doping concentrations of the outer barriers increases the nonlinearity of μ. The oscillatory character of μ is amended by varying the width of the well and barrier and also the height of the VDQW. Our results can be used to study VDQW based nanoscale field effect transistor structures. 相似文献
88.
In this work,the entropy functions of ideal quantum gases in a three-dimensional harmonic trap are analytically calculated using temperature as an explicit variable.Afterward,the applicability of the analytical formulas is validated by comparison with the numerical calculation.The results illustrate that the obtained functions could be applied for the whole temperature regime with a maximum relative deviation of less than 7.5%in the vicinity of the critical temperature Tcin the case of Bose gases.Meanwhile,for Fermi gases,although the analytical formula fits well at very low-and high-temperature regimes,it cannot be applied at temperature in the range[0.3-0.5]T_F,where T_F is the Fermi temperature.In addition,the consistency between our formulas and classical ones at significantly high temperatures is also discussed. 相似文献
89.
Qiong-Tao Xie 《理论物理通讯》2020,72(6):65105-64
An analytical method is developed to study the two-mode quantum Rabi model. For certain specific parameter conditions, especially for the resonant conditions, we obtain an infinite number of the exact solutions of the eigenfunctions and associated energies. It is shown that there exist new types of the exact energies which do not correspond to the level-crossings. Our analytical method may find applications in some related models. 相似文献
90.
《Physics letters. A》2020,384(26):126662
We study the dynamic of magneto-polaron condensate in monolayer two dimensional (2D) transition metal dichalcogenides (TMDs) materials of 2H types in triangular quantum well potential. Within both the quantum mechanical Schrödinger approach (QMSA) and the improved Wigner-Brillouin theory (IWBT), Landau energies levels (LELs) are derived. We have shown that the magneto-polaron condensation is enhanced in monolayer MoSe2 compared to MoS2, WS2 and WSe2. We derive various levels by increasing a magnetic field and laser parameter. We show that the quantum confinement lifts the degeneracy of the Landau levels (LLs) resulting in an anticrossing and crossing. The dephasing effect due to the quantum well potential's parameter plays an important role in the magneto-polaron energy corrections, which are also affected by the amplitude of the laser field. The system presents Stückelberg oscillations which is important for practical applications. 相似文献