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1.
Wang  Tao  He  Jiuyang  Duan  Demin  Jiang  Bing  Wang  Peixia  Fan  Kelong  Liang  Minmin  Yan  Xiyun 《Nano Research》2019,12(4):863-868

Atherosclerotic plaque rupture results in thrombus formation and vessel occlusion, and is the leading cause of death worldwide. There is a pressing need to identify plaque vulnerability for the treatment of carotid and coronary artery diseases. Nanomaterials with enzyme-like properties have attracted significant interest by providing biological, diagnostic and prognostic information about the diseases. Here we showed that bioengineered magnetoferritin nanoparticles (M-HFn NPs) functionally mimic peroxidase enzyme and can intrinsically recognize plaque-infiltrated active macrophages, which drive atherosclerotic plaque progression and rupture and are significantly associated with the plaque vulnerability. The M-HFn nanozymes catalyze the oxidation of colorimetric substrates to give a color reaction that visualizes the recognized active macrophages for one-step pathological identification of plaque vulnerability. We examined 50 carotid endarterectomy specimens from patients with symptomatic carotid disease and demonstrated that the M-HFn nanozymes could distinguish active macrophage infiltration in ruptured and high-risk plaque tissues, and M-HFn staining displayed a significant correlation with plaque vulnerability (r = 0.89, P < 0.0001).

  相似文献   
2.
The corrosion behaviour of 6082 aluminium alloy was studied by measuring the electrochemical impedance spectra and electrode polarization curves. After the electrochemical tests, a microstructural analysis of the samples was conducted by using optical microscopy and electron scanning microscopy techniques to determine the corrosion mechanism. The results show that the Nyquist plot of the electrochemical impedance data in the NaCl solution consists of high- and low-frequency capacitive impedance loops. When ions are added to the NaCl etchant, the Nyquist plots of the electrochemical impedance data are composed of two different curves: a high-frequency capacitive impedance loop and a low-frequency inductive impedance loop. The corrosion current density increases with increasing concentration, and as a result, the corrosion resistance of the aluminium alloy decreases. The microstructures of 6082 aluminium alloy consist of Mg2Si secondary particles in a large α-Al matrix. Pitting corrosion initially occurs at the boundary between the matrix and secondary particles because the electrode potentials of the matrix and secondary particles are different. Then, corrosion paths develop along the network-like grain boundaries, and finally, massive network-like corrosion occurs throughout the entire alloy.  相似文献   
3.
ABSTRACT

In view of the complexity of current detection efficiency calibration of radioactive gas sources, a method using solid planar sources to be equivalent to gas sources was studied. For the 50 mL gas source box, an optimal equivalent scheme was selected by Monte Carlo Simulations. Then, the full-energy-peak efficiency curve of gas sources at the measurement position of 25 cm, with source-to-detector distance of 25 cm, was fitted by measuring solid planar sources with known activity. To verify the accuracy of the efficiency curve, 41Ar, 133Xe and 87Kr gases were produced and determined by length-compensated method. Then, their full-energy-peak efficiencies at 25 cm position away from the detector were directly calibrated. The percentage efficiency deviations between interpolation from the efficiency curve and direct calibration are all less than 2.5%, which proves the accuracy of the equivalent method. This calibration method is a general one and can be also used for some other radioactive sample measurements, such as non-destructive analysis of gaseous fission product samples with a suitable source-to-detector distance.  相似文献   
4.
王雅刚  白林  苏运河 《玻璃》2006,33(2):28-30
分析总结了几种常见配合料加水系统及其特点,并结合生产实际提出了不同系统的利弊和使用要点.  相似文献   
5.
In order to improve vibration mills grinding effect and increase productive efficiency, prime factors of vibration mills were gained much attention. The purpose of this study is to reveal product size distribution and grinding dynamics of vibration mills by orthogonal experi-ments. The metallurgical refractory materials were used as research object. In order to explore the relationships between grinding effect and primary factors, lots of milling experiments were carried out. Based on the results, the conclusions can be summarized: as time runs, the size distri-bution shows exponential trend, and range becomes more and more narrow. Also the quantitative analysis result between grinding effect and primary factors was obtained by non-linear regres-sion: high frequency, high amplitude and low fill ratio can increase grinding speed.  相似文献   
6.
介绍了大同煤矿集团公司平旺地区供水系统概况及供水管网技术管理的内容。  相似文献   
7.
基于C/S模式的煤矿安全管理信息系统,充分利用了传统C/S模式的优势与特点,具有便捷省时的输入方式及其他业务处理功能,图形化数据查询结果等辅助数据管理功能和系统管理功能,可为煤矿领导作出安全决策提供技术支持。  相似文献   
8.
利用光聚合反应制作表面平整的聚合物光栅   总被引:1,自引:0,他引:1  
提出利用紫外光聚合反应来制作聚合物光栅的方法.实验发现,光栅的表面起伏深度很小,约为12.4~0.7nm;折射率调制较大,达到0.010左右.这种方法在低阶分布反馈聚合物激光器的制作中具有很好的应用前景.  相似文献   
9.
摘要介绍了国内、外主要规范关于少筋混凝土构件的设计方法,并作了比较和评述,归纳出一个适用于不同要求的少筋混凝土受弯构件脆性破坏的附加系数公式,作为结构重要性系数的一个组成部分,以便于设计.  相似文献   
10.
1前言岩土工程数值模拟计算经常会遇到曲边界上任意分布荷载的计算问题,现行的前处理常规计算方法是假定其局部线性分布,这不仅影响计算精度,也增加了输入的工作量,因此合理处理曲边界上任意分布荷载的数值计算问题是此类软件开发的前提和基础。本文提出用二次插值函数法计算曲  相似文献   
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