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	Study on corrosion behavior and mechanism of AISI 4135 steel in marine environments based on field exposure experiment 期刊论文 OAI收割 SCIENCE OF THE TOTAL ENVIRONMENT, 2022, 卷号: 830, 页码: 17 作者: Xu, Yong; Huang, Yanliang; Cai, Fanfan; Lu, Dongzhu; Wang, Xiutong \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2022/07/18 Marine environments Corrosion Field exposure experiment Steel
	食用蔬菜能吸收和积累微塑料期刊论文 OAI收割科学通报, 2019, 卷号: 64, 期号: 9, 页码: 928-934 作者: 李连祯; 周倩; 尹娜; 涂晨; 骆永明 \| 收藏 \| 浏览/下载：143/0 \| 提交时间：2020/06/17 微塑料生菜聚苯乙烯微球吸收积累健康风险 microplastics lettuce polystyrene microbeads uptake accumulation human health risk Microplastic (MP, 100 nm-5 mm) may present an attributable risk to ecosystem and human health, and its pollution has become a global environmental concern. Despite a wealth of information on the accumulation of MPs in aquatic species, there is no information on the uptake and accumulation of MPs by higher plants. Terrestrial edible plants are directly exposed to MPs when agricultural soil was applied with organic manure, sewage sludge as fertilizer or plastic mulching. In this paper, the uptake of two sizes of polystyrene (PS) microbeads (0.2 and 1.0 mum) and then their distribution and migration in an edible plant lettuce were firstly investigated based on laboratory experiments. We used fluorescent markers to track PS microbeads in plant tissues and found fluorescence to be a sensitive and reliable detection method. Sections from untreated control lettuce showed no autofluorescence. When roots were treated with fluorescently labeled PS microbeads, the microbeads could be identified by its fluorescence. Our main study investigated the uptake of 0.2 mum beads, as few luminescence signals were observed in lettuce roots for 1.0 mum beads in our experiment. We observed that 0.2 mum fluorescent microbeads were extracellularly trapped in the root cap mucilage (which is a highly hydrated polysaccharide) and a dark green tip (which was typical of lettuce roots exposed to label PS beads) was usually visible to the naked eye. Confocal images revealed that the PS luminescence signals were mainly located in the vascular system and on the cell walls of the cortex tissue of the roots, indicated that the beads passed through the intercellular space via the apoplastic transport system. Once inside the central cylinder, the 0.2 mum PS beads were transferred from the roots to the stems and leaves via the vascular system following the transpiration stream. We also observed that the PS beads adhered to one another and self-assembled systematically into grape-like and (chain) string-like clusters in the intercellular space of the root and stem vascular tissue of lettuce plant. In contrast to the root and stem, PS beads were dispersed in the leaf tissue. Here, for the first time we provide evidence of the adherence, uptake, accumulation, and translocation of submicrometer MPs within an edible plant. Our findings highlight the previously underappreciated human exposure pathway to MPs through the consumption of contaminated crops and emphasize the need for new management strategies to control the release of MPs waste products into the terrestrial environment. Ultimately, the potential impacts of low range sized MPs on food safety of crop plants and human health need to be urgently considered.
	The solid lubricating material experiment device for shenzhou-7 spaceship 期刊论文 iSwitch采集 Science china-technological sciences, 2010, 卷号: 53, 期号: 9, 页码: 2521-2527 作者: Wang Ke; Ren WeiJia; Wang ShiDa; Weng LiJun 收藏 \| 浏览/下载：26/0 \| 提交时间：2019/05/10 Manned spaceflight Exposure experiment Mechanism Unlock
	A design on a control method of a new type of focal plane shutter (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Xue L.; Ming L.; Zheng L.-N.; Zhou J.-F.; Zhang H.-W.; Zhang J.-C. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 In order to ensure appropriate exposure time and no exposure while electric charge is transferring after taking a photograph it is necessary to have the shutter mechanism cooperate with CCD for area CCD aerial cameras. The ground object illumination has a wide range which is from 4000Lx to 100000Lx so a shutter which is high efficient and a continuous stepless adjustment are also required. This paper introduces the fundamental principle structural design and control procedure about this new focal plane shutter. Under the control of DSP the velocity of shutter curtain governed by the shutter motor can be not only precisely controlled but also the durability and the reliability are increased. The experiment results have shown that this new shutter has the higher stability of movement long life span with more than 105 operating times a wide range of exposure time from1/ 50s to 1/ 320s(depending on the slit width)and the exposure error is less than 10%. With the CCD gain adjustment the performance of this shutter is fully satisfied with the requirements of area CCD aerial cameras. 2010 IEEE.
	Development and radiance calibration of three-waveband camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photonics and Optoelectronics, SOPO 2010, June 19, 2010 - June 21, 2010, Chengdu, China 作者: Wang J.; Liu Y.; Liu Y.; Sun Q.; Liu Y. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 An imaging system with three-waveband sharing one lens and an area CCD was developed. By rotating different filters into the beam path the required waveband was selected. The optical system which can image in ultraviolet visible and near infrared region was designed and the signal collecting system was integrated. The optical design and system integration have some advantages such as low cost small size and light in weight. To obtain a high imaging quality the radiation calibration is carried out in order to establish the relation between the average grey level of output image and the input radiance from the integrating sphere. According to the calibration data in experiments the radiation dynamic range and the best working point of the system are determined. The experiment result shows that the dynamic range of the image system is maximal when the exposure time is 8ms in ultraviolet 0.5ms in visible and 0.125ms in near infrared region. 2010 IEEE.
	The application of auto-controlled liquid crystal light valve arrays to photolithography shutter (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China 作者: Chen Y. 收藏 \| 浏览/下载：14/0 \| 提交时间：2013/03/25 Photolithography shutter is usually used to control exposure in order to obtain patterns of code disc and metrology grating which are the core components of optical shaft encoder. But perforated film as photolithography shutter has many disadvantages such as taking too long time to perforate easily making wrong code lower reusable ratio. Mathematical models for resist property luminous efficiency and exposure have been established by deducing their relations for avoiding the disadvantages which provides the theory of using liquid crystal light valve (LCLV) replacing proforated film. Based on operating principles of LCLV and control theories of photolithography shutter the principle diagram of control circuit of LCLV arrays has been designed according to theirs control principles. In the control system LCLV arrays as photolithography shutter are realized by adopting DS75451 to drive them and using AT89C51 chip to control them. By photolithographic experiment the patterns of code disc are good the edges of lines are vertical it indicates LCLV arrays as photolithography shutter may control exposure and light passing accords with the intending requires. It proves using LCLV arrays replacing perforated film as photolithography shutter is feasible completely.