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41.
关于Orlicz空间的H性质的注记   总被引:3,自引:0,他引:3  
该文给出了Orlicz函数空间具有H性质的充分必要条件.  相似文献   
42.
The ability to target the adeno‐associated virus (AAV) to specific types of cells, by altering the cell‐surface receptor it binds, is desirable to generate safe and efficient therapeutic vectors. Chemical attachment of receptor‐targeting agents onto the AAV capsid holds potential to alter its tropism, but is limited by the lack of site specificity of available conjugation strategies. The development of an AAV production platform is reported that enables incorporation of unnatural amino acids (UAAs) into specific sites on the virus capsid. Incorporation of an azido‐UAA enabled site‐specific attachment of a cyclic‐RGD peptide onto the capsid, retargeting the virus to the αvβ3 integrin receptors, which are overexpressed in tumor vasculature. Retargeting ability was site‐dependent, underscoring the importance of achieving site‐selective capsid modification. This work provides a general chemical approach to introduce various receptor binding agents onto the AAV capsid with site selectivity to generate optimized vectors with engineered infectivity.  相似文献   
43.
The repair of critical-sized bone defects remains a major concern in clinical care. Herein, a multifunctional hydrogel is rationally designed to synergistically photothermal antibacterial and potentiate bone regeneration via adding magnesium oxide nanoparticle and black phosphorus nanosheet (BPNS) into poly(vinyl alcohol)/chitosan hydrogel (PVA/CS-MgO-BPNS). Under the dual effect of near-infrared irradiation and CS intrinsic antibacterial properties, PVA/CS-MgO-BPNS hydrogel can kill more than 99.9% of Staphylococcus aureus and Escherichia coli. The released Mg ions stimulate the migration of mesenchymal stem cells (MSCs) to hydrogels and synergize with released phosphate to promote osteogenic differentiation. The PVA/CS-MgO-BPNS hydrogel also promotes calcium phosphate particle formation and therefore improves the biomineralization ability. Furthermore, the potential molecular mechanism of PVA/CS-MgO-BPNS to regulate MSCs migration and differentiation is through activating phosphoinositide 3-kinase (PI3K)-Akt signaling pathways through RNA-seq analysis. Finally, the PVA/CS-MgO-BPNS hydrogel could significantly promote endogenous bone tissue regeneration in the rat skull defect model. Taken together, this easy fabricated multifunctional hydrogel has good clinical applicability for the repair of large-scale bone defects.  相似文献   
44.
Fan  Chao  Jin  Hui  Chen  Yunan  Ge  Zhiwei  Zhao  Qiuyang 《Journal of Thermal Analysis and Calorimetry》2020,141(5):1591-1603
Journal of Thermal Analysis and Calorimetry - Gasification models of a char particle based on the true porous structure are essential for the accurate simulation of gasifiers, and pore-scale study...  相似文献   
45.
针对蔗汁酒精废液中含有的大量色素物,采用大孔树脂吸附提取色素,对蔗汁酒精废液中色素的提取工艺及其抗氧化活性进行了研究。通过静态吸附实验筛选出吸附树脂D101及对应的洗脱溶剂乙醇。最佳流速为3BV/h,最佳洗脱条件为40%的乙醇在pH6~7范围内进行洗脱。经测定,色素的黄酮含量为茶多酚的27.2%,但对自由基的抑制率却为茶多酚的88.06%,表明蔗汁酒精废液中提取的色素具有较高的抗氧化活性。  相似文献   
46.
In this work, we present necessary and sufficient conditions for compactness of the composition operator on Orlicz–Lorentz spaces and determine upper and lower estimates for the essential norm of the composition operator on these spaces.  相似文献   
47.
Maltol, ethyl maltol, vanillin, and ethyl vanillin are important food additives as flavor enhancers. To quantify the four additives in milk powder, a novel 2D liquid chromatographic (2DLC) method was developed in this article. In such a 2DLC system, the target fractions eluted from the first dimensional column (C4) are stored onto the trapping column (C8) for subsequent analysis; after that, they were switched into the second dimensional column (C18) by a two‐position six‐port switching valve. A one‐step sample preparation method was used prior to 2DLC chromatographic analysis, which was easy and convenient. After optimization of all experimental parameters, the new method was validated in terms of linearity, LODs, and LOQs, intra‐ and interday precision, and accuracy. A conventional single‐dimensional liquid chromatographic method was also proposed in this work for comparison. In order to evaluate the applicability of the new 2DLC method, five brands of commercial milk powder samples (n = 8) were analyzed. Vanillin and ethyl vanillin were detected in two samples, respectively. It is showed that the 2DLC method is effective in quality control programs of milk powder products.  相似文献   
48.
In this paper some lower and upper estimates of M‐constants for Orlicz–Lorentz function spaces for both, the Luxemburg and the Amemiya norms, are given. Since degenerated Orlicz functions φ and degenerated weighted sequences ω are also admitted, this investigations concern the most possible wide class of Orlicz–Lorentz function spaces. M‐constants were defined in 1969 by E. A. Lifshits, and used by many authors in the study of lattice structures on Banach spaces, as well as in the fixed point theory.  相似文献   
49.
准共线集成声光模式转换器的性能分析与设计   总被引:2,自引:2,他引:0  
吕敏  崔建民  刘维  崔芳  孙雨南 《光子学报》2005,34(5):662-665
报道了一种SiO2薄膜声波导和Ti∶LiNbO3光波导之间存在一个角度的准共线的模式转换器结构, 利用波导模式分析导出薄膜声波导的宽度限制; 利用模式耦合理论得出了声光模式转换特性和耦合系数的加权形式. 实现了对耦合系数的加权, 较好地抑制了旁瓣. 在综合考虑旁瓣和线宽的条件下, 设计了这种TE/TM声光模式转换器, 其旁瓣为-16.8 dB, -3 dB线宽和-10 dB线宽分别为1.37 nm和2.31 nm.  相似文献   
50.
Criteria for locally uniform convexity of Musielak-Orlicz function spaces of Bochner type equipped with the Luxemburg norm are given. We also prove that, in Musielak-Orlicz function spaces generated by locally uniformly convex Banach space, locally uniform convexity and strict convexity are equivalent.  相似文献   
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