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排序方式: 共有193条查询结果,搜索用时 15 毫秒
91.
92.
In this paper we prove the global existence and uniqueness of smooth solutions to the 2D micropolar fluid flows with zero angular viscosity. 相似文献
93.
In two space dimension, we prove the global existence of smooth solutions to a coupled microscopic-macroscopic co-rotational
FENE dumbbell model which arises from the kinetic theory of diluted solutions of polymeric liquids with noninteracting polymer
chains. 相似文献
94.
The haemocompatibility of phosphorus-incorporated tetrahedral amorphous carbon (ta-C:P) films, synthesized by filtered cathodic vacuum arc technique with PH3 as the dopant source, was assessed by in vitro platelet adhesion tests. Results based on scanning electron microscopy and contact angle measurements reveal that phosphorus incorporation improves the wettability and blood compatibility of ta-C film. Our studies may provide a novel approach for the design and synthesis of doped ta-C films to repel platelet adhesion and reduce thrombosis risk. 相似文献
95.
CHEN Qionglei & ZHANG Zhifei Department of Mathematics Zhejiang University Hangzhou China Academy of Mathematics System Sciences Chinese Academy of Sciences Beijing China 《中国科学A辑(英文版)》2004,47(6):842-853
In this paper we give the (Lα p, Lp) boundedness of the maximal operator of a class of super singular integrals defined bywhich improves and extends the known result. Moreover, by applying an off-Diagonal T1 Theorem, we also obtain the (Lp, Lq) boundedness of the commutator defined by 相似文献
96.
Chemodynamic therapy kills cancer cells with reactive oxygen species generated by endogenous triggers in the tumor microenvironment. Although chemodynamic therapy is blossoming in recent years, their therapy process still faces a series of hampers. The unknown catalytic activity of chemodynamic therapy reagents may lead to unpredictable therapy effects, so it is necessary to reveal the therapeutic mechanism of chemodynamic therapy and develop self-monitoring probes. In this mini-review, we summarize and illustrate the most recent progress of chemodynamic therapy, focusing on the applications of magnetic imaging and optical imaging probe for monitoring cancer chemodynamic therapy. Furthermore, we also discuss the potential challenges and the further directions of this field. 相似文献
97.
刚性球形传声器阵列可以在无空间模糊的条件下进行球谐域数据处理,基于球形阵列的可控波束形成器导向响应功率(SRP)算法定位精度高,但是计算量大,计算效率低。通过将球面致密的全局网格搜索替换为分层搜索策略可以有效减小SRP算法的计算量。提出MRE-SRP算法保持球形阵列SRP定位精度的同时降低计算量,首先通过球谐域MUSIC(SH-MUSIC)算法判断入射声源的数量减小搜索区域;其次将相对熵模型引入球谐域SRP(SH-SRP)定位算法中,提取网格分层前后的信息增益,设计自适应网格选择判据,实现分层多分辨率网格的精准再细分,从而降低计算量。实验验证了所提出算法的性能,结果显示在单双声源定位中,该算法可以实现较高的定位精度,精准选择分层网格,计算量减少75%以上。 相似文献
98.
WFQEM‐based perturbation approach and its applications in analyzing nonlinear periodic structures 下载免费PDF全文
Based on the weak form quadrature element method, a perturbation approach is developed. Waves propagating in periodic beams on a nonlinear elastic foundation are studied by using the new proposed method. The feasibility and accuracy of the proposed method are verified by comparing the present results with those available in literatures in linear cases. Detailed modal analysis of the linear cases is conducted in order to obtain the dispersion relations of the nonlinear cases. The theoretical results show that the dispersion relations of the nonlinear cases are amplitude dependent. Furthermore, the effects of geometric parameters and degree of nonlinearity on the amplitude‐dependent dispersion relations are discussed in detail. This work provides a new method for analyzing the dispersion relations of nonlinear periodic structures and gives some useful guidelines for designing periodic beams or pipelines with nonlinear structure–foundation interaction. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
99.
A sensitive method for carbon tetrachloride (CCl4) determination has been developed with the aid of ultrasonic oxidation decolorization of methyl orange (MO). It is found that the ultrasonic oxidation decolorization rate of MO can be significantly promoted by adding a little amount of CCl4. The increased ultrasonic decolorization rate of MO is strongly dependent on the concentration of CCl4 added, and a linear correlation is observed between the amount of CCl4 and the decolorization rate of MO in the ultrasonic oxidation process. Thus, the CCl4 determination is transformed to a simple and direct determination of the decoloration extent of MO solution at a given concentration. As an indirect spectrophotometric determination of CCl4, the new method is sensitive and easy of operation with a maximum wavelength of 508 nm, molar absorptivity of 3.83 × 104 L mol−1 cm−1, and a Sandell sensitivity of 7.96 × 10−3 μg cm−2. Under optimized conditions, Beer's law is obeyed in the range of 0.4-20 mg L−1 of CCl4 (DL = 0.19 mg L−1, r = 0.9996). The concentrations of CCl4 in several practical samples have been determined satisfactorily by using this method. 相似文献
100.
本研究通过原位引发聚合方法,以合成的4,4'-偶氮(4-氰基戊酸酯基)四苯乙烯(TPE-tetraAZO)为引发剂,引发乙烯基吡咯烷酮单体聚合,并通过侧链含孤对电子的N、O元素与稀土Eu(III)配位,成功制备四臂星型聚合物TPE-tetraPVP-Eu(III),该双亲性聚合物可自组装成尺寸约为20 nm的非半导体型聚合物量子点(Pdots).光学性能研究表明:该Pdots在360 nm和395 nm激发下分别发射蓝色(435 nm)和红色(615 nm)荧光,其中,Pdots的蓝色荧光具有典型的AIE特性,并对环境温度和pH具有明显双重响应特性,最低临界温度为37℃,接近人体温度.此外,Pdots表现出低细胞毒性,可通过调节激发波长,实现对HeLa、HepG2及A549三种肿瘤细胞的可逆双色荧光成像,展现出优异的成像效果,有望作为一种活细胞多色荧光示踪探针材料. 相似文献