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1.
采用一步微波法成功制备了表面带氨基的荧光纳米碳点CDots, 并通过酰胺化反应将靶向基团叶酸接枝到碳点表面, 成功获得中间产物CDots-FA. 在此基础上, 通过已合成四臂端酰肼基化合物2与抗肿瘤药物阿霉素(DOX)连接, 实现在碳点表面的阿霉素药物分子的化学键合, 最终获得多功能纳米载药体系DOX-CDots-FA. 利用原子力显微镜(AFM)、高分辨透射电镜(HR-TEM)和荧光光谱仪对荧光纳米碳点CDots的性能进行表征, 并通过核磁共振、紫外-可见吸收光谱对DOX-CDots-FA结构、接枝率进行了表征. 同时对纳米载药体系DOX-CDots-FA体外药物释放行为、细胞毒性及细胞摄取成像进行了系统的研究. 结果表明, DOX-CDots-FA具有良好的pH响应性. 叶酸靶向基团能加速DOX-CDots-FA被HeLa (FR+)细胞摄取, 并表现出更强的细胞毒性. 同时细胞摄入成像实验表明, 在叶酸靶向作用下, DOX-CDots-FA通过内吞作用进入HeLa细胞, 随后阿霉素被释放出来并进入细胞核区域, 抑制细胞的生长, 从而实现靶向治疗, 降低毒副作用.  相似文献   
2.
Merocyanine (MC) dyes exhibit facile synthesis and attractive optical properties, making them widely studied as the donor materials in organic solar cells (OSCs). In this study, for the first time, simple indole-based MCs are successfully designed as unfused nonfullerene acceptors (NFAs) for OSCs by forming dimers with A−D-π-D−A structure, which possess enhanced photostability compared to the well-known ITIC acceptor and high electron mobility in blend films. When blended with P3HT donor, one of the dimers, i. e. Z2, shows a good cell efficiency of 3.53 %, which outperforms the performance of most of P3HT/NFA blends, particularly for unfused systems, and thus indicates good potential of simple MCs as NFAs.  相似文献   
3.
A filtered backprojection (FBP) reconstruction algorithm for attenuated fan-beam projections has been derived based on Novikov's inversion formula. The derivation uses a common transformation between parallel-beam and fan-beam coordinates. The filtering is shift-invariant. Numerical evaluation of the FBP algorithm is presented as well. As a special application, we also present a shift-invariant FBP algorithm for fan-beam SPECT reconstruction with uniform attenuation compensation. Several other fan-beam reconstruction algorithms are also discussed. In the attenuation-free case, our algorithm reduces to the conventional fan-beam FBP reconstruction algorithm.  相似文献   
4.
Let (C,E,s) be an extriangulated category with a proper class ξ of E-triangles.We study complete cohomology of objects in (C,E,s) by applying ξ-projective resolutions and ξ-injective coresolutions constructed in (C,E,s).Vanishing of complete cohomology detects objects with finite ξ-projective dimension and finite ξ-injective dimension.As a consequence,we obtain some criteria for the validity of the Wakamatsu tilting conjecture and give a necessary and sufficient condition for a virtually Gorenstein algebra to be Gorenstein.Moreover,we give a general technique for computing complete cohomology of objects with finite ξ-Gprojective dimension.As an application,the relations between ξ-projective dimension and ξ-Gprojective dimension for objects in (C,E,s) are given.  相似文献   
5.
Applied Mathematics and Mechanics - The flow around a square cylinder with a synthetic jet positioned at the rear surface is numerically investigated with the unsteady Reynolds-averaged...  相似文献   
6.
基于卡尔曼滤波算法的汽车运动参数测试方法研究   总被引:5,自引:0,他引:5  
提出了一种采用多维组合惯性测量元件进行汽车运动参数测试的方法,并利用卡尔曼滤波算法提高了测试系统的精度。仿真结果表明:卡尔曼滤波算法对汽车姿态、速度等的解算具有较好的效果。  相似文献   
7.
This article is a continuous work of [17 Hu , J. , Zhang , D. ( 2013 ). Weak AB-context for FP-injective modules with respect to semidualizing modules . J. Algebra Appl. 12 ( 7 ): 1350039 .[Crossref], [Web of Science ®] [Google Scholar]], where the coauthors introduced the notion of 𝒢-FP-injective R-modules. In this article, we define a notion of 𝒢-FP-injective dimension for complexes over left coherent rings. To investigate the relationships between 𝒢-FP-injective dimension and FP-injective dimension for complexes, the complete cohomology group bases on FP-injectives is given.  相似文献   
8.
高效液相色谱-蒸发光散射检测法测定烟草中的水溶性糖   总被引:20,自引:0,他引:20  
杨俊  刘江生  蔡继宝  朱晓兰  高芸  苏庆德 《分析化学》2005,33(11):1596-1598
采用Waters高效糖分析柱,梯度洗脱分离,建立了高效液相色谱-蒸发光散射检测法(HPLC—ELSD)同时测定烟草中水溶性糖的新方法。乙腈-水为流动相,流速1.0mL/min,柱温30℃,蒸发光散射检测器漂移管温度80℃,氮气作载气,流速2.00L/min。水溶性糖的线性范围:鼠李糖、果糖、葡萄糖、蔗糖0.5—30μg,检出限低于12.5ng;木糖、阿拉伯糖、甘露糖、麦芽糖0.5—20μg,检出限低于25.0ng。8种水溶性糖的加标回收率范围为86.0%~102.4%;相对标准偏差(n=5)皆小于4.1%。  相似文献   
9.
We study complete cohomology of complexes with finite Gorenstein AC-projective dimension. We show first that the class of complexes admitting a complete level resolution is exactly the class of complexes with finite Gorenstein AC-projective dimension. This lets us give some general techniques for computing complete cohomology of complexes with finite Gorenstein AC-projective dimension. As a consequence, the classical relative cohomology for modules of finite Gorenstein AC-projective dimension is extended. Finally, the relationships between projective dimension and Gorenstein AC-projective dimension for complexes are given.  相似文献   
10.
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