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11.
Zeolitic Imidazolate Framework-8 (ZIF-8), for the first time for ZIFs, exhibits a remarkable capacity for the anticancer drug 5-fluorouracil (5-FU), around 660 mg of 5-FU/g of ZIF-8, and presents a pH-triggered controlled drug release property. These prove ZIF-8 to be a valuable candidate for delivery of anticancer agents and reveal its potential applications in the treatment of cancer.  相似文献   
12.
A new organic-inorganic hybrid, [Cu(en)(2)](3){[Cu(en)(2)][H(6)SiNb(18)O(54)]}·22H(2)O (1, en = ethylenediamine) containing the crescent-shaped polyoxoanion [H(6)SiNb(18)O(54)](8-) and copper-organic cations has been successfully synthesized, and elemental analyses, IR spectra, thermogravimetric analyses and single-crystal X-ray diffraction were investigated.  相似文献   
13.
An unprecedented organic-inorganic hybrid {[Cu(6)L(6)(H(2)O)(3)][Nb(10)V(4)O(40)(OH)(2)]}(2)·13H(2)O (1) (L = 1,10-phenanthroline) containing the unreported {Nb(10)V(4)O(40)(OH)(2)}(12-) building blocks has been successfully synthesized and its photoluminescent properties, IR spectra, thermogravimetric analyses and single-crystal X-ray diffraction were investigated.  相似文献   
14.
In this paper, we put our focus on a variable-coe~cient fifth-order Korteweg-de Vries (fKdV) equation, which possesses a great number of excellent properties and is of current importance in physical and engineering fields. Certain constraints are worked out, which make sure the integrability of such an equation. Under those constraints, some integrable properties are derived, such as the Lax pair and Darboux transformation. Via the Darboux transformation, which is an exercisable way to generate solutions in a recursive manner, the one- and two-solitonic solutions are presented and the relevant physical applications of these solitonic structures in some fields are also pointed out.  相似文献   
15.
电击法磁性纳米颗粒作为水稻转基因载体的研究   总被引:2,自引:0,他引:2  
建立了以磁性纳米颗粒为载体,由电击法介导基因导入植物细胞的优化方法。制备了粒径小于10nm的磁性纳米颗粒,与绿色荧光蛋白(Green fluorescent protein,GFP)基因融合制备基因载体,同时,制备水稻悬浮细胞,加入电极杯中,调节电击条件为:电压分别是800,1000和1200V,电容25μF,电阻200Ω,直径10mm,电击数次。利用倒置荧光显微镜观察转化后的悬浮细胞,可以明显看到绿色荧光蛋白在水稻细胞内表达。说明纳米颗粒基因载体在电击作用下能有效进入细胞,利用磁性纳米颗粒作为基因载体电击法转化植物细胞初步成功。  相似文献   
16.
In the present paper, the authors introduce two new subclasses of close-to-convex functions and of quasi-convex functions. The integral representations for functions belonging to these classes are provided, the convolution conditions, growth theorems, distortion theorems and covering theorems for these classes are also provided. The results obtained generalize some known results, and some other new results are obtained.  相似文献   
17.
Fingerprints are the most common personal identification feature and key evidence for crime scene investigators. The prediction of fingerprints features include gender, height range (tall or short), left or right hand, and finger position can effectively narrow down the list of suspects, increase the speed of comparison, and greatly improve the effectiveness of criminal investigations. In this study, we used three commonly used CNNs (VGG16, Inception-v3, and Resnet50) to perform biometric prediction on 1000 samples, and the results showed that VGG16 achieved the highest accuracy in identifying gender (79.2%), left- and right-hand fingerprints (94.4%), finger position (84.8%), and height range (69.8%, using the ring finger of male participants). In addition, we visualized the CNN classification basis by the Grad-CAM technique and compared the results with those predicted by experts and found that the CNN model outperformed experts in terms of classification accuracy and speed, and provided good reference for fingerprints that were difficult to determine manually.  相似文献   
18.
The coordinating properties of N-o-chlorobenzamido-meso-tetraphenylporphyrin (N-NHCO(o-Cl)C6H4-Htpp; 11) have been investigated for the Zn2+ ion. Insertion of Zn results in the formation of the zinc complex Zn(N-NCO(o-Cl)C6H4-tpp)(MeOH) · MeOH (12 · MeOH). The diamagnetic 12 · MeOH can be transformed into the diamagnetic Zn(N-NHCO(o-Cl)C6H4-tpp)Cl · CH2Cl2 (13 · CH2Cl2) in a reaction with aqueous hydrogen chloride (2%). X-ray structures for 12 · MeOH and 13 · CH2Cl2 have been determined. The coordination sphere around the Zn2+ ion in 12 · MeOH is a distorted trigonal bipyramid with N(2), N(4) and O(2) lying in the equatorial plane, whereas for the Zn2+ ion in 13 · CH2Cl2, it is a square-based pyramid in which the apical site is occupied by the Cl(1) atom.  相似文献   
19.
In this paper, the multisoliton solutions in terms of double Wronskian determinant are presented for a generalized variable-coefficient nonlinear Schrödinger equation, which appears in space and laboratory plasmas, arterial mechanics, fluid dynamics, optical communications and so on. By means of the particularly nice properties of Wronskian determinant, the solutions are testified through direct substitution into the bilinear equations. Furthermore, it can be proved that the bilinear Bäcklund transformation transforms between (N − 1)- and N-soliton solutions.  相似文献   
20.
Applicable in fluid dynamics and plasmas, a generalized variable-coefficient Korteweg-de Vries (vcKdV) model is investigated. The bilinear form and analytic N-soliton-like solution for such a model are derived by the Hirota method and Wronskian technique. Additionally, the bilinear auto-Bǎcklund transformation between (N-1)- soliton-like and N-soliton-like solutions is verified.  相似文献   
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