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81.
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
82.
Miao Kan Zhifei Wang Yan Xingtao Wang Jeremy L. Hitt Langqiu Xiao Jeffrey M. McNeill Yong Wang Yixin Zhao Thomas E. Mallouk 《Angewandte Chemie (International ed. in English)》2020,59(28):11462-11469
A molecularly thin layer of 2‐aminobenzenethiol (2‐ABT) was adsorbed onto nanoporous p‐type silicon (b‐Si) photocathodes decorated with Ag nanoparticles (Ag NPs). The addition of 2‐ABT alters the balance of the CO2 reduction and hydrogen evolution reactions, resulting in more selective and efficient reduction of CO2 to CO. The 2‐ABT adsorbate layer was characterized by Fourier transform infrared (FTIR) spectroscopy and modeled by density functional theory calculations. Ex situ X‐ray photoelectron spectroscopy (XPS) of the 2‐ABT modified electrodes suggests that surface Ag atoms are in the +1 oxidation state and coordinated to 2‐ABT via Ag?S bonds. Under visible light illumination, the onset potential for CO2 reduction was ?50 mV vs. RHE, an anodic shift of about 150 mV relative to a sample without 2‐ABT. The adsorption of 2‐ABT lowers the overpotentials for both CO2 reduction and hydrogen evolution. A comparison of electrodes functionalized with different aromatic thiols and amines suggests that the primary role of the thiol group in 2‐ABT is to anchor the NH2 group near the Ag surface, where it serves to bind CO2 and also to assist in proton transfer. 相似文献
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Science China Mathematics - In this paper, we study the stability of shear flows of Prandtl type as $$left({Uleft({y/sqrt nu} right),0} right)$$ for the steady Navier-Stokes equations under a... 相似文献
85.
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
86.
本文介绍了空气动力学中几个基本概念与定律的起源。其中,升力与阻力分别是空气对物体作用力的两个方向上的分量,它们均是由空气与物体的相对运动而产生的,并与该运动速度的平方成正比。库塔儒可夫斯基升力环量定理给出了翼型升力与翼型绕流之间的关系,开启了20世纪早期各国对翼型性能的研究。同时,鉴于理想流体圆柱绕流无阻力的理论结果与实验观察存在的矛盾开始激发人们对黏性流体运动的研究兴趣,并由此诞生了纳维斯托克斯方程组。而后普朗特提出边界层概念,巧妙解决了局部流动与整体流动的关系问题。针对大展弦比直机翼,普朗特又提出了基于升力线假设的升力线模型,并根据翼型气动数据得到三维机翼的气动性能。 相似文献
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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
90.
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