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91.
A hydrophilic and temperature-induced degradation drug, vinorelbine bitartrate (VB)-loaded phosphatidylethanolamin sterically stabilized liposomes (PSLs) were prepared by the thin film hydration method. Liposomes were made of phosphatidylethanolamine: cholesteryl: oleic acid (PE: CHOL: OA, 6:4:3 mass/mass). The mean particle size of the PSLs ranged from 600 to 650 nm. The transmission electron microscope (TEM) images displayed that the shape of the PSLs was multilamellar vesicles with smooth surface. The highest entrapment efficiency (EE) and drug loading capacity (DL) could reach up to 81.2 and 16.6%, respectively. The studies of drug release showed that the drug release could last for much more than 48 hours. The PSLs was evaluated by comparing the rate of release of encapsulated VB in different phosphate buffer solution (PBS). 相似文献
92.
The condensation of indene or 2-nitrofluorene with aromatic aldehydes catalyzed by bis-(p-methoxyphenyl)telluroxide (BMPTO) under ultrasonic wave irradiation gave corresponding fulvenes in fair to good yield. 相似文献
93.
L. Lam H. C. Morris R. F. Shao S. L. Yang Z. C. Liang S. Zheng 《Liquid crystals》2013,40(6):1813-1826
The theoretical and experimental developments in the interfacial dynamics and the formation of viscous fingering patterns in Hele-Shaw cells of liquid crystal-air systems are summarized and discussed. These include radial and linear cells with or without grooves engraved on the cell plates. Instabilities of fingers, the role of intrinsic and extrinsic anisotropies, etc., are emphasized. In a linear cell, when the injected air is kept at constant pressure, a whole sequence of successive instabilities of fingers (hump, tip-splitting, sidewrinkling, sidebranching and DLA-like structure) is observed in a single run of the experiment. In our theory, the equations of motion of nematic flows in Hele-Shaw cells are derived from the Ericksen-Leslie equations. In the linear approximation, the equations resemble those of isotropic liquids with the presence of effective viscosities and anisotropic surface tension. Experimental observations are interpreted with the introduction of an effective control parameter which may be time dependent. Special features of viscous fingers in liquid crystals in contrast to those in isotropic liquids, such as asymmetric dendritics, displacement of the finger from the central axis of the linear cell, and reentrant sequence of patterns, are pointed out. Plausible explanations of these phenomena are given. In this newly developed field, a large number of interesting problems remain to be solved. 相似文献
94.
95.
Motivated by a recent London penetration depth measurement [H. Kim, et al., Phys. Rev. Lett. 114, 027003 (2015)] and novel composite pairing scenario [O. Erten, R. Flint, and P. Coleman, Phys. Rev. Lett. 114, 027002 (2015)] of the Yb-doped heavy fermion superconductor CeCoIn5, we revisit the issue of superfluid response in the microscopic heavy fermion lattice model. However, from the literature, an explicit expression for the superfluid response function in heavy fermion superconductors is rare. In this paper, we investigate the superfluid density response function in the celebrated Kondo–Heisenberg model. To be specific, we derive the corresponding formalism from an effective fermionic large-N mean-field pairing Hamiltonian whose pairing interaction is assumed to originate from the effective local antiferromagnetic exchange interaction. Interestingly, we find that the physically correct, temperature-dependent superfluid density formula can only be obtained if the external electromagnetic field is directly coupled to the heavy fermion quasi-particle rather than the bare conduction electron or local moment. Such a unique feature emphasizes the key role of the Kondo-screening-renormalized heavy quasi-particle for low-temperature/energy thermodynamics and transport behaviors. As an important application, the theoretical result is compared to an experimental measurement in heavy fermion superconductors CeCoIn5 and Yb-doped Ce1?xYbxCoIn5 with fairly good agreement and the transition of the pairing symmetry in the latter material is explained as a simple doping effect. In addition, the requisite formalism for the commonly encountered nonmagnetic impurity and non-local electrodynamic effect are developed. Inspired by the success in explaining classic 115-series heavy fermion superconductors, we expect the present theory will be applied to understand other heavy fermion superconductors such as CeCu2Si2 and more generic multi-band superconductors. 相似文献
96.
97.
It has been proved that there exists a certain correlation between fingertip temperature oscillations and blood flow oscillations. In this work, a porous media model of human hand is presented to investigate how the blood flow oscillation in the endothelial frequency band influences fingertip skin temperature oscillations. The porosity which represents the density of micro vessels is assumed to vary periodically and is a function of the skin temperature. Finite element analysis of skin temperature for a contra lateral hand under a cooling test was conducted. Subsequently, wavelet analysis was carried out to extract the temperature oscillations of the data through the numerical analysis and experimental measurements. Furthermore, the oscillations extracted from both numerical analyses and experiments were statistically analyzed to compare the amplitude. The simulation and experimental results show that for the subjects in cardiovascular health, the skin temperature fluctuations in endothelial frequency decrease during the cooling test and increase gradually after cooling, implying that the assumed porosity variation can represent the vasomotion in the endothelial frequency band. 相似文献
98.
Yan Liang Dian He Deshun Zhou Junshuai Li Lei Tang Zhen Wang 《Molecules (Basel, Switzerland)》2021,26(16)
A series of 16 new derivatives of harmine N9-Cinnamic acid were synthesized and fully characterized using NMR and MS. The in vitro antibacterial evaluation revealed that most of the synthesized harmine derivatives displayed better antibacterial activities against Gram-positive strains (S. aureus, S. albus and MRSA) than Gram-negative strains (E. coli and PA). In particular, compound 3c showed the strongest bactericidal activity with a minimum inhibitory concentration of 13.67 μg/mL. MTT assay showed that compound 3c displayed weaker cytotoxicity than harmine with IC50 of 340.30, 94.86 and 161.67 μmol/L against WI-38, MCF-7 and HepG2 cell lines, respectively. The pharmacokinetic study revealed that the distribution and elimination of 3c in vivo were rapid in rats with an oral bioavailability of 6.9%. 相似文献
99.
Juan Yang Qiwan Li Luxiang Wang Jinliang Shao Li Wang 《International journal of environmental analytical chemistry》2019,99(3):282-296
In this study, a convenient and sensitive analytical method based on dispersive solid-phase extraction (dSPE) and gas chromatography-tandem mass spectrometry in tandem was developed for the simultaneous determination of six chloroacetamide herbicides (acetochlor, alachlor, metolachlor, metazachlor, butachlor and pretilachlor) in soil. Parameters that could influence the extraction efficiency such as the varieties of solvents, the amount of solvents and sorbents were investigated. The optimized extractions were performed by mixing 5.0 g of dried soil with 10.0 mL acetonitrile, 10.0 mL deionized water and 4.0 g sodium chloride, and then the extract was purified with 50.0 mg N-propyl ethylenediamine (PSA), 50.0 mg C18, 10.0 mg graphitized carbon black (GCB) and 100.0 mg MgSO4 (5:5:1:10). At 5.0, 25.0 and 100.0 ng g?1 fortification levels for each analyte, the average obtained recoveries ranged from 87.7% to 108.0% with relative standard deviation (RSD) between 3.8% and 10.9%. The soil matrix effect of the six compounds were lower than 11.0%. The linear relation was observed in the range of 5.0–500.0 ng g?1 and the correlation coefficient (R2) of these compounds were higher than 0.998. The detection limits (LODs) were in the range of 0.2–1.0 ng g?1, and the limits of quantification (LOQs) were between 0.8 and 2.2 ng g?1. Comparing with the gas chromatography-electron capture detector (GC-ECD), the GC-tandem mass spectrometry (MS/MS) method can improve the anti-interference ability and thus get better separation of the chloroacetamide herbicides. Additionally, this method was verified to fit for soil samples with broad organic matter range (16.2 to 83.0 g kg?1). The developed method was successfully applied for analysing 26 field soil samples collected from Dianchi lake basin in the southeast of China. About 42.0% soil samples were detected with these herbicides, of which butachlor was the most frequently detected and the highest concentration was up to 137.0 ng g?1 in rape soil. 相似文献
100.
Nonlinear Dynamics - This paper is concerned with the problem of nonfragile control for a class of fuzzy switched systems with mode-dependent time-varying delays. By constructing novelty Lyapunov... 相似文献