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1.
Journal of Optimization Theory and Applications - We consider the conic linear program given by a closed convex cone in an Euclidean space and a matrix, where vector on the right-hand side of the...  相似文献   
2.
Herein, we investigated the analytical features of potentiometric immunosensors for detection of alpha-fetoprotein (AFP) in hepatocellular carcinoma at different electrodes, such as carbon fiber microelectrode (CFME) and carbon-disk electrode (CDE), respectively. To construct such an immunosensor, anti-AFP capture antibodies were first conjugated covalently onto the activated electrodes through typical carbodiimide coupling. Thereafter, one-step immunoreaction protocol was successfully introduced to develop a new potentiometric immunoassay upon addition of AFP. Accompanying the antigen-antibody reaction, the surface charges of the modified electrodes were changed for the readout of electric potential. Results indicated that the linear range of CDE-based immunosensor was 0.1–100 ng mL−1 AFP, whereas the assay sensitivity by using CFME could be further increased to 3.2 pg mL−1 with the linear range from 0.01 to 500 ng mL−1 AFP. Meanwhile, CFME-based immunosensor showed high sensitivity, good reproducibility and specificity, and could be utilized for the analysis of human serum specimens with consistent results relative to commercialized ELISA kit.  相似文献   
3.
Sim  Woojeong  Lee  Booyeong  Kim  Dong Ju  Lee  Jeong A  Kim  Jaewon  Chung  Jintai 《Nonlinear dynamics》2022,108(2):987-1004
Nonlinear Dynamics - This study analyzes the vibro-impact behavior of two adjacent cantilever beams subjected to vibration generated by applying harmonic excitation to their rigid base. For the...  相似文献   
4.
Rechargeable Mg batteries (RMBs) are advantageous large-scale energy-storage devices because of the high abundance and high safety, but exploring high-performance cathodes remains the largest difficulty for their development. Compared with oxides and sulfides, selenides show better Mg-storage performance because the weaker interaction with the Mg2+ cation favors fast kinetics. Herein, nanorod-like FeSe2 was synthesized and investigated as a cathode for RMBs. Compared with microspheres and microparticles, nanorods exhibit higher capacity and better rate capability with a smaller particle size. The FeSe2 nanorods show a high capacity of 191 mAh g−1 at 50 mA g−1 and a good rate performance of 39 mAh g−1 at 1000 mA g−1. Ex situ characterizations demonstrate the Mg2+ intercalation mechanism for FeSe2, and a slight conversion reaction occurs on the surface of the particles. The capacity fading is mainly because of the dissolution of Fe2+, which is caused by the reaction between Fe2+ and Cl of the electrolyte during the charge process on the surface of the particles. The surface of FeSe2 is mainly selenium after long cycling, which may also dissolve in the electrolyte during cycling. The present work develops a new type of Mg2+ intercalation cathode for RMBs. More importantly, the fading mechanism revealed herein has considered the specificity of Mg battery electrolyte and would assist a better understanding of selenide cathodes for RMBs.  相似文献   
5.
高超飞行器在中低空以极高马赫数飞行时, 飞行器表面会遇到湍流与高温非平衡效应耦合作用的新问题. 这种高焓湍流边界层壁面摩阻产生机制是新型高超声速飞行器所关注的基础科学问题, 厘清此产生机制可以为减阻方法的设计提供指导, 具有重要的工程实用价值. 本文选取高超声速飞行时楔形体头部斜激波后的高焓流动状态, 开展了考虑高温非平衡效应的湍流边界层直接数值模拟研究, 并设置同等边界层参数下的低焓完全气体湍流边界层流动作为对比, 采用RD (Renard & Deck)分解技术研究了高焓湍流边界层摩阻的主要产生机制, 对摩阻产生的主要贡献项积分函数分布进行了详细分析, 研究了高温非平衡效应对摩阻产生的影响规律; 采用象限分析技术, 研究了摩阻分解湍动能生成项的主导流动事件. 计算结果表明, 高温非平衡效应会使得壁面摩阻脉动条带的流向和展向尺寸均减小. 分子黏性耗散项和湍动能生成项是高焓湍流边界层摩阻生成的主要流动过程. 分子黏性耗散项主要作用在近壁区, 高焓流动的分布与低焓流动存在差异. 象限分析表明, 上抛和下扫运动是影响摩阻分解中湍动能生成项的主导事件.   相似文献   
6.
Acta Mathematicae Applicatae Sinica, English Series - In this paper, we investigate a delayed HIV infection model that considers the homeostatic proliferation of CD4+ T cells. The existence and...  相似文献   
7.
Liu  Kang  Wang  Rujing  Zheng  Shijian  Dong  Shifeng  Sun  Guowei 《Nonlinear dynamics》2022,107(3):2363-2390
Nonlinear Dynamics - This study focuses on the design of a fixed-time disturbance observer-based robust fault-tolerant tracking control scheme for an uncertain quadrotor unmanned aerial vehicle...  相似文献   
8.
当前锂离子动力电池电化学模型存在模型复杂、建模难度大、计算效率低、老化评估效果差的问题,本文提出一种考虑电池衰退老化的机理模型(ADME).本文首先通过有限差分法对伪二维(P2D)电化学模型进行离散降阶处理,得到简化伪二维(SP2D)模型.在SP2D模型的基础上,基于阴阳两极发生的副反应导致的衰退老化现象,提出一种考虑电池衰退老化的机理模型.其次,使用多变量偏差补偿最小二乘法实现模型参数辨识.最后通过动力电池衰退老化性能循环实验,对比分析了恒流、脉冲工况下SP2D模型和ADME模型的终端电压输出.结果表明:ADME模型较为简单、计算效率和估算精度高,可以有效评估电池容量老化衰退,得到理想的锂离子动力电池外特性曲线.  相似文献   
9.
Zhang  Yicai  Zhao  Min  Sun  Dihua  Dong  Chen 《Nonlinear dynamics》2021,103(2):1891-1909

With the development of vehicle technology, the number of vehicles equipped with the adaptive cruise control (ACC) system is increasing, and it is more and more common for ACC vehicles to drive with regular vehicles. In this work, we proposed a mixed traffic model with regular vehicles and ACC vehicles via the transformation of micro-model and macro-model. The linear stability analysis tells that the permeability of ACC vehicles has an important influence on the traffic system. Meanwhile, through the nonlinear analysis, the KdV–Burgers equation describing the density wave is obtained. Besides, the results of numerical simulations are consistent with the theory, which indicates that the increase in ACC vehicles is conducive to the stability of the transportation system.

  相似文献   
10.
Zhao  Tianqi  Luo  Tianzi  Fang  Bo  Shi  Lijiang  Jin  Yongxing  Zhou  Pengwei  Yao  Dong  Li  Chenxia  Jing  Xufeng  Hong  Zhi 《Journal of Russian Laser Research》2021,42(5):586-597
Journal of Russian Laser Research - The zero-refractive-index metamaterials have excellent electromagnetic properties, which provide new ideas and methods to realize the control of electromagnetic...  相似文献   
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