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91.
双波段成象及融合技术研究 总被引：3，自引：4，他引：3
概括地分析了双波段成象技术的发展概况，分析了成象技术的基本原理，提出了红外双波段基本方案和涉及的关键技术，分析和计算了系统的基本性能。最后，讨论了双波段及融合技术，认为在双波段实现融合应以自主式结构为主。 相似文献
92.
生物组织样品的光学特性可以由光学相干层析成像系统探测到的后向散射功率确定，文中建立了入射光线在样品介质内的一阶散射数学模型，揭示了样品的衰减系数和后向散射系数与系统探测结果之间的关系。 相似文献
93.
微焦点X射线成像设备FXS-160包括微焦点X光机、图像增强器、5个运动自由度物品台等,适合于检测集成芯片、电路板、小型器件等,在监视器上可实时获得物体的透视图像。以微焦点X射线成像设备为基础,开发遵循DICOM标准的小型PACS系统,完成微焦点X射线图像的采集与传输,提供了一个可扩展性强、架构灵活的辐射成像实验平台,并为辐射成像工业应用标准的建立进行了有益的尝试。 相似文献
94.
95.
Eoin G. McAleer Mustafa K. Alazzawi Chawon Hwang Jacob M. LaManna David L. Jacobson Boris Khaykovich Richard A. Haber E. Koray Akdoğan 《Journal of the American Ceramic Society》2023,106(7):4399-4410
Stereolithography of ceramics remains one of the most powerful additive manufacturing routes for the creation of intricate ceramic parts. Despite its utility as a forming tool, ceramic stereolithography requires a challenging debinding stage due to the requisite high polymeric loading. Earlier research has identified both the polymeric resin composition and debinding atmosphere to be crucial factors in improving debinding performance. Here, we use a combination of thermogravimetric analysis and neutron imaging to examine samples of different compositions printed using the same processing and exposure parameters. We quantify the influence of both polyethylene glycol addition and the use of different debinding atmospheres (argon and vacuum) on the debinding behavior of ceramic pellets. Specifically, we demonstrate a method for examining the concentration gradients that develop during thermal debinding with the aid of neutron tomography. We find that at a constant heating rate of 1°C/min up to 500°C, vacuum atmosphere appears to result in a greater number of cracks as compared to the use of argon. The vacuum atmosphere led to the development of lower concentration gradients in the samples on average. The greatest improvement resulted with the addition of polyethylene glycol to the samples. This addition led to significantly less cracking and much lower concentration gradients in samples during debinding. These results prompt us to conclude that while keeping printing and exposure parameters constant, composition modification has a more significant effect on the debinding improvement than heating atmosphere. 相似文献
96.
Ashley J. Saltzman Alex D. Brown Kevin Wan Julien L. Manin Lyle M. Pickett Marc C. Welliver Daniel R. Guildenbecher 《Propellants, Explosives, Pyrotechnics》2023,48(3):e202200167
Fireballs produced from the detonation of high explosives often contain particulates primarily composed of various phases of carbon soot. The transport and concentration of these particulates is of interest for model validation and emission characterization. This work proposes ultra-high-speed imaging techniques to observe a fireball's structure and optical depth. An extinction-based diagnostic applied at two wavelengths indicates that extinction scales inversely with wavelength, consistent with particles in the Rayleigh limit and dimensionless extinction coefficients which are independent of wavelength. Within current confidence bounds, the extinction-derived soot mass concentrations agree with expectations based upon literature reported soot yields. Results also identify areas of high uncertainty where additional work is recommended. 相似文献
97.
Jiayu Zeng Minhui Liu Dr. Songjiao Li Prof. Dr. Dan Cheng Prof. Dr. Longwei He Prof. Dr. Lin Yuan 《Chembiochem : a European journal of chemical biology》2023,24(12):e202300035
Conventional chemotherapy (CT) is associated with severe side effects and inducible resistance, making it difficult to meet clinical requirements, forcing the development of new multifunctional prodrugs for precision medicine. In recent decades, researchers and clinicians have focused on developing of multifunctional chemotherapeutic prodrugs with tumor-targeting capability, activatable and traceable chemotherapeutic activity, as a powerful tool to improve theranostic outcomes in cancer treatment. The conjugates of near-infrared (NIR) organic fluorophores and chemotherapy reagents create an exciting avenue for real-time monitoring of drug delivery and distribution, as well as the combination of chemotherapy and photodynamic therapy (PDT). Therefore, there are great opportunities for researchers to conceive and exploit multifunctional prodrugs that can visualize chemo-drugs release and tumor treatment in vivo. In this review, the design strategy and the recent progress of multifunctional organic chemotherapeutic prodrugs for activating NIR fluorescence imaging-guided therapy are described and discussed in detail. Finally, the prospects and challenges of multifunctional chemotherapeutic prodrugs for NIR fluorescence imaging-guided therapy are provided. 相似文献
98.
《中国化学工程学报》2024,72(8):220-225
The construction of a stable-membrane tracker has significant implications for the visualization of the membrane in live cells.However,most current plasma trackers are not suitable for tracking plasma membranes for a long time due to their limited retention time.Herein,Mem580-F-Sulfo is designed to target and anchor cell membranes and therefore track cell membranes for a longer time.This tracker is composed of a lipophilic boron-dipyrromethene(BODIPY)derivative and a hydrophilic zwitterion to form an amphiphilic structure,which enables its targeting ability toward cell membranes.Moreover,a reactive ester group is included to bind with proteins through covalent bonds in cell membranes non-specifically,which extends retention time in cell membranes.Mem580-F-Sulfo shows intense bright-ness(94600),with a high molar absorption coefficient of up to about 100000 L·mol-1·cm-1 and a fluorescence quantum yield of up to 0.97.It shows fast cell membrane targeting ability and long retention up to 90 min.In brief,this work has not only developed a tracker with good cell membrane targetability but also provided a new strategy for improving the targeting stability of cell membranes. 相似文献
99.
《Fuel Cells》2018,18(2):195-205
The knowledge of heat loss from the fuel cell will be helpful to decide on material components and fixture design. In the present study, a new methodology is proposed to estimate heat loss from passive DMFC using interferometry technique. Printed circuit board (PCB) fixture is adapted in our study that replaces end plate and current collector. The accurate cell temperature distribution is useful to estimate the heat from the cell fixture. The cell temperature distribution is measured based on infra‐red (IR) thermography and this temperature distribution is used to estimate the heat transfer coefficient of the fuel cell. Differential interferometer (DI) technique is used to estimate the heat transfer under different operating conditions of the fuel cell. The cell surface temperature measured on the cathode gas diffusion layer (GDL) is 42 °C for 5M methanol concentration whereas for 1M, it is 32 °C. Based on the analysis , the average heat transfer coefficient of the cell at vertical PCB rib orientation using 5M methanol concentration is estimated to be 2.7 Wm−2 K−1. A two‐dimensional non‐isothermal single‐phase half‐cell (cathode) model is developed and compared with experiments. The cell temperature distribution obtained from model is in good agreement with experiments. The model is extended to study the effect of PCB orientation and thermal conductivity of PCB material on heat loss. The cell at vertical PCB rib orientation retains 15 ‐ 20% more heat than horizontal rib. Therefore, the cell temperature showed 42 °C and performed 10% better compared to horizontal PCB rib. 相似文献
100.
BackgroundOptical techniques, including computer vision, spectral imaging, near-infrared technology and other emerging imaging and spectroscopy techniques, have been rapidly developing and widely applied in fruit and vegetable grading systems for nondestructive quality inspecting and grading over the past decades. However, automatic detection of quality and grading is still difficult due to some still existing challenges, which are the key of blocking their commercialization in robotic fruit and vegetable grading systems. The challenges include the following aspects: the influence of physical and biological variability, whole surface detection, discrimination between defects and stems/calyxes, unobvious defect detection, robustness of the features and algorithms, as well as rapid optical detection system development. These challenges can reduce the fruit or vegetable quality inspection accuracy, thus greatly reducing automatic level of the quality inspecting and grading machines.Scope and approachAs agricultural engineers with about eight years of technical experience in fruit grading systems, we believe the ultimate goal of each scientific research should seek its task in serving the engineering. So, we have made many attempts to solve the challenges and increase the automation of the grading machines.Key findings and conclusionsThe review gives a detailed summary about the challenges and solutions of optical-based nondestructive quality inspection for fruit or vegetable grading systems from the perspective of engineering. Particular attention has been paid to the techniques that can improve the automation degree of the grading robot in this review. The advantages and disadvantages of the solutions are compared and discussed. Additionally, the remaining engineering challenges and future trends are also discussed. 相似文献