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71.
Aligned poly(L-lactide) (PLLA)/poly(?-caprolactone) (PCL)/hydroxyapaite (HA) composite fibrous membranes were fabricated by electrospinning. Their morphology, thermal stability, mechanical properties, hydrophilic properties and biocompatibility were investigated. The electrospun fibers are highly aligned and the HA are oriented along the fiber axis. When HA are incorporated, the PLLA/PCL/HA composite fibers become thinner due to the increased conductivity. In addition, the aligned HA reinforce the electrospun fibrous membranes. The larger porosity and higher hydrophilic properties induced by HA in the electrospun fibers have improved the degradation of the PLLA/PCL/HA fibrous membranes which have no toxic effect on proliferation of adipose-derived stem cells.  相似文献   
72.
李登峰  燕敦验 《数学学报》2004,47(3):527-530
本文证明:如果来自多尺度分析(伸缩因子为矩阵)的小波是标准正交的,那么相对应的尺度函数也是标准正交的,其中函数f_s(x)∈L~2(R~n)(s=1,2,…,r,r是正整数)的标准正交性是指f_s(x)的整平移所构成的函数族为L~2(R~n)的标准正交系。结果表明,如果我们想从多尺度分析出发构造正交小波,那么该多尺度分析必须有正交尺度函数。  相似文献   
73.
由完全分解水的特殊性出发,从材料的结构和能带设计以及材料的表面修饰等方面对完全分解水光催化剂的研制及其分解水产氢产氧性能进行了评述.介绍了Z型体系在完全分解水制氢方面的原理,以及目前已经开发出来的几个Z型体系.对光催化完全分解水研究中存在的问题进行了简单分析.  相似文献   
74.
Dong  Kaifeng  Xu  Kun  Zhou  Youyou  Zuo  Chao  Wang  Leimin  Zhang  Chuanke  Jin  Fang  Song  Junlei  Mo  Wenqin  Hui  Yajuan 《Nonlinear dynamics》2022,109(3):2129-2141
Nonlinear Dynamics - A new type of weak signal detection system that combines the memristor and Van der pol-Duffing chaotic system has been proposed in this paper, and the dynamic characteristics...  相似文献   
75.
Herein, we design and synthesize a novel all-carbon supramolecular polymer host (SPh) containing conjugated macrocycles interconnected by a linear poly(para-phenylene) backbone. Applying the supramolecular host and fullerene C60 as the guest, we successfully construct a supramolecular polymeric heterojunction (SPh⊃C60). This carbon structure offers a means to explore the convex–concave π–π interactions between SPh and C60. The produced SPh was characterized by gel permeation chromatography, mass spectrometry, FTIR, Raman spectroscopy, and other spectroscopies. The polymeric segment can be directly viewed using a scanning tunneling microscope. Femtosecond transient absorption and fluorescence up-conversion measurements revealed femtosecond (≪300 fs) electron transfer from photoexcited SPh to C60, followed by nanosecond charge recombination to produce the C60 triplet excited state. The potential applications of SPh⊃C60 in electron- and hole-transport devices were also investigated, revealing that C60 incorporation enhances the charge transport properties of SPh. These results expand the scope of the synthesis and application of supramolecular polymeric heterojunctions.

Herein, we design and synthesize a novel all-carbon supramolecular polymer host (SPh) containing conjugated macrocycles interconnected by a linear poly(para-phenylene) backbone.  相似文献   
76.
Qiao  Liangzhi  Wang  Shanshan  Du  Kaifeng 《Cellulose (London, England)》2021,28(13):8419-8428
Cellulose - It remains a formidable challenge to construct high-performance haemoperfusion adsorbents with fast adsorption kinetic and high adsorption capacity for efficiently removing bilirubin...  相似文献   
77.
采用Mindlin壳元,对SPF/DB工艺进行了模拟。利用罚函数方法,对板材自身接触问题进行分析,给出了接触板材间的接触力,并提出一种接触搜索判断方法,同时给出了算例。  相似文献   
78.
Hybrid organic-inorganic compounds have attracted increasing interest in recent years due to the possibility of combination of different characteristics of the compounds to get unusual structures, properties, or applications1. Polyoxometalates (POMs) whic…  相似文献   
79.
As an analogue to thermally activated delayed fluorescence (TADF) of organic molecules, thermally activated delayed photoluminescence (TADPL) observed in molecule-functionalized semiconductor nanocrystals represents an exotic mechanism to harvest energy from dark molecular triplets and to obtain controllable, long-lived PL from nanocrystals. The reported TADPL systems have successfully covered the visible spectrum. However, TADF molecules already emit very efficiently in the visible, diminishing the technological impact of the less-efficient nanocrystal-molecule TADPL. Here we report bright, near-infrared TADPL in lead-free CuInSe2 nanocrystals functionalized with carboxylated tetracene ligands, which results from efficient triplet energy transfer from photoexcited nanocrystals to ligands, followed with thermally activated reverse energy transfer from ligand triplets back to nanocrystals. This strategy prolonged the nanocrystal exciton lifetime from 100 ns to 60 μs at room temperature.  相似文献   
80.
Abstract In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities for them.  相似文献   
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