In this study, indoor air quality （IAQ） assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines： sem...In this study, indoor air quality （IAQ） assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines： semi-automatic and automatic. Air samples were collected and analyzed in situ for 4 times, once per 2 hours, during working time of 8 hours. Analysis of the experimental data showed that ambient ozone concentrations slowly increases with the increasing of TVOCs concentration and intensive use of UV lamps during automatic screen printing process. Therefore, the detected concentration levels of ozone and VOCs were compared with the Occupational Safety and Health Administration （OSHA） and Serbian Regulation. Comparison of the two mentioned standard regulations, the ozone concentrations in indoor printing air were from 0.83 to 8.1 and 2.4 to 16.2 times higher in the relation to the prescribed PEL and maximum allowed concentration （MAC） values, respectively, while the concentrations of particular VOCs were much below the PEL prescribed by the OSHA.展开更多
Ultraviolet(UV)visualization has extensive applications in military and civil fields such as security monitoring,space communication,and wearable equipment for health monitoring in the internet of things(IoT).Due to t...Ultraviolet(UV)visualization has extensive applications in military and civil fields such as security monitoring,space communication,and wearable equipment for health monitoring in the internet of things(IoT).Due to their remarkable optoelectronic features,perovskite materials are regarded as promising candidates for UV light detecting and imaging.Herein,we report for the first time the excitationdependent perovskite/polymer films with dynamically tunable fluorescence ranging from green to magenta by changing the UV excitation from 260 to 380 nm.And they still render dynamic multicolor UV light imaging with different polymer matrixes,halogen ratios,and cations of perovskite materials.The mechanism of its fluorescence change is related to the chloride vacancies in perovskite materials.A patterned multi-color ultraviolet visualization pad is also demonstrated for visible conversion of the UV region.This technique may provide a universal strategy for information securities,UV visualizations,and dynamic multi-color displays in the IoT.展开更多
报道了一种基于厚膜工艺的氢气传感器。首先采用丝网印刷工艺制作铂加热器线条,再在其上面分别覆有纳米催化剂/氧化铝形成气敏元件、涂覆纳米氧化铝构成补偿元件,最后制成氢气传感器。测试结果表明:传感器灵敏度大于21 m V/1%H2,响应时...报道了一种基于厚膜工艺的氢气传感器。首先采用丝网印刷工艺制作铂加热器线条,再在其上面分别覆有纳米催化剂/氧化铝形成气敏元件、涂覆纳米氧化铝构成补偿元件,最后制成氢气传感器。测试结果表明:传感器灵敏度大于21 m V/1%H2,响应时间小于30 s,非线性和重复性优于2%。展开更多
文摘In this study, indoor air quality （IAQ） assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines： semi-automatic and automatic. Air samples were collected and analyzed in situ for 4 times, once per 2 hours, during working time of 8 hours. Analysis of the experimental data showed that ambient ozone concentrations slowly increases with the increasing of TVOCs concentration and intensive use of UV lamps during automatic screen printing process. Therefore, the detected concentration levels of ozone and VOCs were compared with the Occupational Safety and Health Administration （OSHA） and Serbian Regulation. Comparison of the two mentioned standard regulations, the ozone concentrations in indoor printing air were from 0.83 to 8.1 and 2.4 to 16.2 times higher in the relation to the prescribed PEL and maximum allowed concentration （MAC） values, respectively, while the concentrations of particular VOCs were much below the PEL prescribed by the OSHA.
基金supported by the National Natural Science Foundation of China(52125205,11974317,11674290,U20A20166,U1704138,52192614,61805015,and 61804011)the National Key R&D Program of China(2021YFB3200302 and 2021YFB3200304)+5 种基金Natural Science Foundation of Beijing Municipality(Z180011 and 2222088)Shenzhen Science and Technology Program(KQTD20170810105439418)the Fundamental Research Funds for the Central UniversitiesHenan Science Fund for Distinguished Young Scholars(212300410020)Key Project of Henan Higher Education(21A140001)the Zhengzhou University Physics Discipline Improvement Program。
文摘Ultraviolet(UV)visualization has extensive applications in military and civil fields such as security monitoring,space communication,and wearable equipment for health monitoring in the internet of things(IoT).Due to their remarkable optoelectronic features,perovskite materials are regarded as promising candidates for UV light detecting and imaging.Herein,we report for the first time the excitationdependent perovskite/polymer films with dynamically tunable fluorescence ranging from green to magenta by changing the UV excitation from 260 to 380 nm.And they still render dynamic multicolor UV light imaging with different polymer matrixes,halogen ratios,and cations of perovskite materials.The mechanism of its fluorescence change is related to the chloride vacancies in perovskite materials.A patterned multi-color ultraviolet visualization pad is also demonstrated for visible conversion of the UV region.This technique may provide a universal strategy for information securities,UV visualizations,and dynamic multi-color displays in the IoT.
