{"title":"A combined virtual impactor and field-effect transistor microsystem for particulate matter separation and detection","authors":"Yanna Li, Muqing Fu, W. Pang, Ye Chang, X. Duan","doi":"10.1063/10.0003447","DOIUrl":"https://doi.org/10.1063/10.0003447","url":null,"abstract":"Ambient suspended particulate matter (PM) (primarily with particle diameter 2.5 µm or less, i.e., PM2.5) can adversely affect ecosystems and human health. Currently, optical particle sensors based on light scattering dominate the portable PM sensing market. However, the light scattering method has poor adaptability to different-sized PM and adverse environmental conditions. Here, we design and develop a portable PM sensing microsystem that consists of a micromachined virtual impactor (VI) for particle separation, a thermophoretic deposition chip for particle collection, and an extended-gate field-effect transistor (FET) for particle analysis. This system can realize on-site separation, collection, and analysis of aerosol particles without being influenced by environmental factors. In this study, the design of the VI is thoroughly analyzed by numerical simulation, and mixtures of different-sized silicon dioxide (SiO2) particles are used in an experimental verification of the performance of the VI and FET. Considering the low cost and compact design of the whole system, the proposed PM analysis microsystem has potential for PM detection under a wide range of conditions, such as heavily polluted industrial environments and for point-of-need outdoor and indoor air quality monitoring.","PeriodicalId":35428,"journal":{"name":"Nami Jishu yu Jingmi Gongcheng/Nanotechnology and Precision Engineering","volume":"4 1","pages":"013003"},"PeriodicalIF":3.7,"publicationDate":"2021-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/10.0003447","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43400065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Deep-learning-based nanowire detection in AFM images for automated nanomanipulation","authors":"Huitian Bai, Sen Wu","doi":"10.1063/10.0003218","DOIUrl":"https://doi.org/10.1063/10.0003218","url":null,"abstract":"Atomic force microscope (AFM)-based nanomanipulation has been proved to be a possible method for assembling various nanoparticles into complex patterns and devices. To achieve efficient and fully automated nanomanipulation, nanoparticles on the substrate must be identified precisely and automatically. This work focuses on an autodetection method for flexible nanowires using a deep learning technique. An instance segmentation network based on You Only Look Once version 3 (YOLOv3) and a fully convolutional network (FCN) is applied to segment all movable nanowires in AFM images. Combined with follow-up image morphology and fitting algorithms, this enables detection of postures and positions of nanowires at a high abstraction level. Benefitting from these algorithms, our program is able to automatically detect nanowires of different morphologies with nanometer resolution and has over 90% reliability in the testing dataset. The detection results are less affected by image complexity than the results of existing methods and demonstrate the good robustness of this algorithm.","PeriodicalId":35428,"journal":{"name":"Nami Jishu yu Jingmi Gongcheng/Nanotechnology and Precision Engineering","volume":"4 1","pages":"013002"},"PeriodicalIF":3.7,"publicationDate":"2021-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/10.0003218","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47685610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A twist sensor based on polarization-maintaining fibers with different cladding diameters","authors":"Xiaoqi Liu, Yan-ge Liu, Zhi Wang","doi":"10.1063/10.0003338","DOIUrl":"https://doi.org/10.1063/10.0003338","url":null,"abstract":"A fiber twist sensor using a Sagnac interferometer incorporating a tapered polarization-maintaining fiber (PMF) is proposed. The transmission properties of the sensor are investigated both theoretically and experimentally. Given the optoelastic effect, which depends on fiber geometry, the modal and group birefringences of the PMF can be controlled by applying different twist angles. The spectral wavelength shifts, free spectral ranges, and transmission losses of the original, microtapered, and etched PMFs were compared. Notably, the interference dips for the etched PMF move in opposite directions. As a result, the proposed PMF-based sensor could have multiparameter sensing applications.","PeriodicalId":35428,"journal":{"name":"Nami Jishu yu Jingmi Gongcheng/Nanotechnology and Precision Engineering","volume":"4 1","pages":"023001"},"PeriodicalIF":3.7,"publicationDate":"2021-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/10.0003338","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46240730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Propagation characteristics of photonic crystal fibers selectively filled with ionic liquid","authors":"Xiaoqi Liu, Yan-ge Liu, Zhi Wang","doi":"10.1063/10.0002950","DOIUrl":"https://doi.org/10.1063/10.0002950","url":null,"abstract":"We present a numerical and experimental study of the propagation characteristics of photonic crystal fibers (PCFs) selectively filled with ionic liquid (IL; 1-butyl-3-methylimidazolium iodine). Three types of IL-filled PCF are investigated: one with all air holes filled, one with an IL-filled air hole in the second ring, and one with an IL-filled air hole in the third ring. The results show that the third type of IL-filled PCF is the most sensitive to temperature; the sensitivity of resonant dips between the LP01 and LP21 modes is ∼−2.9 nm/°C. Moreover, the intensity of the resonant dips changes with the polarization angle of the light source; the sensitivity is ∼−0.79 dB per unit polarization angle. Based on this property, IL-filled PCFs with different utilities can be realized by changing the filling position flexibly. Consequently, IL-filled PCFs can be used under flexible conditions and controllable temperatures to create a compact polarization-angle sensor.","PeriodicalId":35428,"journal":{"name":"Nami Jishu yu Jingmi Gongcheng/Nanotechnology and Precision Engineering","volume":"4 1","pages":"013001"},"PeriodicalIF":3.7,"publicationDate":"2021-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/10.0002950","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45305266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}