水中悬浮颗粒是水体物质的重要成分，因此监测它们的种类和浓度对研究和保护水生态系统具有重要科学意义和实用价值。文中研制了一种水中悬浮颗粒分类仪（Suspended Particle Classifier, SPC），旨在现场检测野外采集的水样，快速得出水中悬浮颗粒的种类、数量和比例。SPC采用引流管将颗粒输送至散射体积内，通过同时探测单个颗粒的散射光偏振态和荧光信号，结合机器学习算法对颗粒分类。对沉积物、微塑料和微藻的标准样品做了数据集并训练分类器，SPC能以大于95%的预测正确率对它们进行分类。接着，将SPC和商业水质多参数监测仪（QWA）同时在崖门水道连续布放25个小时。SPC能快速测量现场采集的水样，获取不同水层的沉积物、微塑料和微藻的数量随时间的变化情况。SPC给出的微藻数量与QWA测得的叶绿素a浓度以及藻红蛋白浓度之间存在显著的相关性；此外，SPC给出的沉积物等效时间截面和QWA测得的浊度值也呈现出明显的相关性，由此可以证明SPC分类结果的可靠性。结果表明：SPC能够对水中的悬浮颗粒进行现场快速分类检测，有望成为探索水生态系统的关键技术。

Brillouin light scattering (BLS) spectroscopy is a label-free method of measuring the GHz-frequency viscoelastic properties. The measured longitudinal modulus is acutely sensitive to the degree of hydration, crosslinking, and temperature, which can be indicative of tissue health. As such, performing in situ measurements on humans is particularly desirable for exploring potential clinical translation, however, is not possible with existing designs which are coupled to bench-top microscopes. Here we introduce a robust fiber coupled hand-held BLS probe and demonstrate its reliability for measuring excised human tissue. We verify its accuracy using confocal BLS microscopy and further show that it is possible to distinguish veins, arteries, nerves and muscles based on their BLS-measured viscoelasticity. This provides a necessary first step towards in situ clinical BLS viscoelasticity studies of human tissue.

In this study a commercial particle analyzer was used to image and help sorting microplastic particles (MPs) dispersed in filtrated and de-aerated tap water. The device provides a relatively easy and fast procedure for obtaining ultra-high-definition imaging, allowing the determination of shape, size, and number of 2D-projections of solid particles. The image analysis revealed clear differences among the studied different MPs originating from the grinding of five common grades of plastic sheets as they affect the image rendering differently, principally due to the light scattering either at the surface or in the volume of the microplastics. The high-quality imaging of the device also allows the discrimination of the microplastics from air bubbles with well-defined spherical shapes as well as to obtain an estimate of the size of MPs in a snapshot. We associate the differences among the shapes of the identified MPs in this study depending on the plastic type with known physical properties, such as brittleness, crystallinity, or softness. Furthermore, as a novel method we exploit a parameter based on the light intensity map from moving particles in cuvette flow to sort MPs from other particles, such as, wood fiber, human hair, and air bubbles. Using the light intensity map, which is related to the plastic-water refractive index ratio, the presence of microplastics in water can be revealed among other particles, but not their specific plastic type.

利用双峰颗粒样品相关函数的相对衰减特性，提出基于衰减特性的长延时相关函数相继提取法。该方法分别定义小颗粒相关函数拟合窗口的起始点，间隔点和大颗粒相关函数拟合窗口的终止点。首先，将间隔点定义为相对衰减特性极小值对应的延迟时间；其次，以间隔点为界，根据相对衰减特性图纵坐标最大值与其他纵坐标值的比例关系，确定小颗粒相关函数拟合窗口的起始点与大颗粒相关函数拟合窗口的终止点。以此三个参考点作为相关函数拟合窗口的选取准则，对拟合窗口进行优化选择，减小窗口选择的盲目性，从而提高粒度反演结果的准确性。模拟数据与实验数据表明，改进的优化算法反演结果显著降低了颗粒粒径相对误差、峰值位置相对误差以及相关函数均方根误差，提出的基于衰减特性的长延时相关函数相继提取法优于传统长延时相关函数相关提取法。

Terahertz (THz) technology offers novel opportunities in biology and medicine, thanks to the unique features of THz-wave interactions with tissues and cells. Among them, we particularly notice strong sensitivity of THz waves to the tissue water, as a medium for biochemical reactions and a main endogenous marker for THz spectroscopy and imaging. Tissues of the brain have an exceptionally high content of water. This factor, along with the features of the structural organization and biochemistry of neuronal and glial tissues, makes the brain an exciting subject to study in the THz range. In this paper, progress and prospects of THz technology in neurodiagnostics are overviewed, including diagnosis of neurodegenerative disease, myelin deficit, tumors of the central nervous system (with an emphasis on brain gliomas), and traumatic brain injuries. Fundamental and applied challenges in study of the THz-wave – brain tissue interactions and development of the THz biomedical tools and systems for neurodiagnostics are discussed.

流体工质的热、质扩散系数是表征其传热和传质的重要迁移性质，往往需要采用不同设备测量获得。为探索可同时测量热、质扩散系数的动态光散射方法，研究了采样时间、入射角、黏度、折射率偏差及路易斯数Le等因素对测量可靠性及精度的影响。利用二元混合流体正己烷/正癸烷、正己烷/正十六烷体系进行验证，结果表明：当采样时间为弛豫时间的1.5~3倍且入射角度为8°~12°时，具有较低黏度、较高折射率偏差（>4%）的体系且Le值为10~80时，可以同时可靠地获取流体热、质扩散系数，且测量不确定度低于5%；与已有方法对比，热、质扩散系数的偏差分别为4.00%和3.56%，证明了该测量方法和系统的可靠性。