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黄海桑沟湾水体及沉积物中微塑料污染特征研究 期刊论文 OAI收割
海洋环境科学, 2019, 卷号: 38, 期号: 2, 页码: 198-204
作者: 熊宽旭; 赵新月; 周倩; 付传城; 涂晨

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桑沟湾微塑料潮滩丰度空间分布 Sanggou bay microplastics tidal flats abundance spatial distribution In recent years,research on microplastics pollution in the marine environment has been increasing,but studies on microplastics in water bodies and sediments of the bay under the influence of high-intensity human activities are still rarely reported. In this study,the pollution characteristics of microplastics in the wayer and sediments of Sanggou bay were investigated in December 2017,after the harvest of large-scale aquaculture,with the aim to study the effects of aquaculture activities and hydrodynamics on pollution characteristics and spatial distribution of microplastics in the bay. The results showed that the types of microplastics in the water and sediments of Sanggou bay were mainly fibers,fragments,films,foams and particles. The microplastic abundances in the water and sediments were 1.8 ~ 31.2 N/L,31.2 ~ 1246.8 N/kg,respectively. The average particle sizes of microplastics in water and sediments were 0.51 0.20 mm and 1.54 1.02 mm,respectively. The results of spatial distribution of microplastics in Sanggou bay showed that the high abundance area mainly appears in the inshore waters,and the abundance of microplastics tends to decrease from the inner areas of estuary to the outshore areas. The heterogeneity of microplastic abundance and spatial distribution in Sanggou bay is mainly affected by human activities such as aquaculture,living and shipping,as well as hydrodynamics. In the future,fine sampling and analysis are needed to fully understand the temporal and spatial distribution of microplastics pollution in the bay areas.

In-orbit Demonstration of X-Ray Pulsar Navigation with the Insight-HXMT Satellite 期刊论文 OAI收割
The Astrophysical Journal Supplement Series, 2019, 卷号: 244, 页码: 1
作者: HXMT

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收藏 | 浏览/下载：13/0 | 提交时间：2022/02/08

pulsars: general techniques: miscellaneous Astrophysics - Instrumentation and Methods for Astrophysics Abstract: In this work, we report the in-orbit demonstration of X-ray pulsar navigation with Insight-Hard X-ray Modulation Telescope (Insight-HXMT) Satellite, which was launched on 2017 June 15. The new pulsar navigation method Significance Enhancement of Pulse-profile with Orbit-dynamics is adopted to determine the orbit with observations of only one pulsar. In this test, the Crab pulsar is chosen and observed by Insight-HXMT from 2017 August 31 to September 5. Using the five-day long observation data, the orbit of Insight-HXMT is determined successfully with the three telescopes onboard: High Energy X-ray Telescope, Medium Energy X-ray Telescope, and Low Energy X-ray Telescope, respectively. By combining all the data, the position and velocity of the Insight-HXMT are pinpointed to within 10 km (3ҩ and 10 m s^-1 (3ҩ, respectively.

Synthesis, characterization, and ethylene polymerization behaviors of late-transition metal complexes coordinated with chlorinated bis(arylimino)pyridine ligand 期刊论文 OAI收割
polymer, 2014, 卷号: 55, 期号: 18, 页码: 4611-4618
Liu, Heng; Wang, Feng; Liu, Li; Jai,Xiang-Yu; Zheng,Wenjie; Guo,Jun; Zhang,Chun-Yu; Bai,Chen-Xi; Hu,Yan-Ming; Zhang,Xue-Quan

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A series of late-transition metal complexes supported with chlorinated bis(arylimino)pyridine ligands [2 Ar = 2 Ar = 2 Ar = 2 Ar = 4-Cl-2 Ar = 4-Br-2 6-(ArN=CCl)(2)C5H3N]MtCl(2) (Ar = 2 6-(Pr2C6H3)-Pr-i 6-Et2C6H3 6-Me2C6H3 6-Me2C6H2 6-Me2C6H2 4 Mt = Fe (1b) Mt = Co (1c) Mt = Fe (1d) Mt = Fe (1e) Mt = Fe (1f) 6-Me3C6H2 Co (2b) Ni (3c) Co (2d) Co (2e) Co (2f)) were synthesized. At the presence of methylaluminoxane (MAO) Mt = Fe (1a) Fe(II)- and Co(II)- based complexes were highly active towards ethylene polymerization Co (2a) affording polymers with bimodal and unimodal molar. mass distributions Ni (3a) respectively while the Ni(II)-based complexes gave no polymer products. Moreover the obtained polyethylenes were predominately saturated and vinyl-terminated for Fe(II)- and Co(II)-based complexes respectively. Changing the ligand environment polymerization parameters also posed a great influence on the catalytic activities and the properties of the resulting polymers. (C) 2014 Elsevier Ltd. All rights reserved.

Structural design of large aperture rectangular mirror for space telescope (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Civil Engineering and Transportation, ICCET 2012, October 27, 2012 - October 28, 2012, Guilin, China
作者: Li Z.; Li Z.

收藏 | 浏览/下载：41/0 | 提交时间：2013/03/25

Structural design of large aperture mirror is one of the key technologies for space telescope development. To meet the requirements of high stiffness strength and thermal dimensional stability some factors such as support scheme materials selection lightweight design and flexible support design were taken into account. The three supports location of the mirror was determined according to the modal analytical solution. By adjusting the parameters of flexure hinge influences of gravity assembly stress and thermal stress on the mirror were reduced obviously. Finite element analysis (FEA) results indicate that the surface accuracy reach to rms10.2nm and 10.8nm under the gravity along optical axis direction and 5C uniform temperature rise respectively the fundamental frequency of the mirror component is 268Hz. Dynamics test shows that the first order natural frequency is 256Hz which shows an error less than 5% compared to FEA results. (2013) Trans Tech Publications Switzerland.

Structural design and simulation analysis of ejector used in automotive power steering oil discharge equipment (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Mechanical Engineering, Materials Science and Civil Engineering, ICMEMSCE 2012, August 18, 2012 - August 20, 2012, Harbin, China
Cheng K.; Zou H.; Kong X.; Tang J.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

The structure of ejector used in automotive power steering oil discharge equipment is designed in accordance with the theory of gas-liquid ejector.The two important parameters of the ejector are elected respectively to five values and then 25 ejector models are obtained by the permutations and combinations.The ejector's CFD model is created by Fluent module of Ansys then it is divided into a grid and analyzed. Analyse its pressure distribution and velocity vector which provides the optimal size for the manufacture of the ejectors and a theoretical basis for experiment. (2013) Trans Tech Publications Switzerland.

Luminescence and energy transfer in Ca3Sc2Si 3O12:Ce3+,Mn2+ white LED phosphors (EI CONFERENCE) 会议论文 OAI收割
作者: Luo Y.; Zhang J.; Zhang J.

收藏 | 浏览/下载：36/0 | 提交时间：2013/03/25

Expanded emission spectra ranging from green to red are reported in Ca 3Sc2Si3O12 (CSS):Ce 3+ Mn2+ silicate garnets. Mn2+ may occupy Ca2 site (Mn2+(I)) to generate a yellow emission band at 574 nm or Sc3 site (Mn2+(II)) with red emission band at 680 nm. Efficient energy transfers from the green emitting Ce3+ to both Mn2+(I) and Mn2+(II) occur upon blue excitation into Ce3+. Concentration dependence of Mn2+ emission is analyzed based on Ce3+-Mn2+ energy transfer steady state rate equations and fluorescence lifetimes. Energy transfer efficiency (nT) and rate (W) are calculated with values as high as 45% and 14.01106 s-1 respectively. 2011 Elsevier B.V.

Design and implementation of a single actuated bio-mimetic robotic fish (EI CONFERENCE) 会议论文 OAI收割
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
作者: Wang X.; Wang X.; Wang X.

收藏 | 浏览/下载：52/0 | 提交时间：2013/03/25

The mechanical structure of a single actuated bio-mimetic robotic fish was designed based on forced vibration responses of a non-prismatic cantilever which mimicked the fish body deformation. To realize the cruising turning and burst-and-coast moving modes the hardware system based on the micro controller unit STM32F103C8T6 and the control were developed. The state variable feedback method and PID method were used to design the control algorithms respectively. The simulation and experimental results showed that the whole system could imitate the swimming of the real fish. 2012 IEEE.

Comparison and simulation of subpixel imaging modes for linear CCD (EI CONFERENCE) 会议论文 OAI收割
2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China
作者: Li Y.; He B.; Li Y.; Li Y.; Li Y.

收藏 | 浏览/下载：36/0 | 提交时间：2013/03/25

Subpixel technique of linear CCD is effective to enhance the spatial resolution without increasing the focal length of optics and reducing the pixel size. To compare image quality of two main subpixel imaging modes quincunx sampling and four-point sampling a method to quantitatively evaluate image quality of subpixel based on MTF was proposed. The MTF of quincunx and four-point sampling modes were derived. Analytical results shows that theoretical limiting resolution of quincunx sampling and four-point sampling is improved to 1.4 and 1.86 times respectively and MTF values at Nyquist frequency of two modes are increased by 0.1106 and 0.1679 respectively. MTFA in (0 0.5) of two subpixel imaging modes were calculated and results illustrates that four-point sampling offers much more improvement with image quality than quincunx sampling at the cost of double amount of data. A model for simulating subpixel imaging using Matlab was established and simulation results of spoke target verify the theoretical analysis. (2012) Trans Tech Publications Switzerland.

Analysis on the influence of random vibration on MEMS gyro precision and error compensation (EI CONFERENCE) 会议论文 OAI收割
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
作者: Li M.

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In order to improve its precision in dynamic environment a Kalman filter was designed. Firstly two sets of random drift data of MEMS gyro were respectively analysed and it was found that the variance of random drift under random vibration significantly increased and its mean also changed. Then calculation results show that attitude angle error under random vibration is 2.6 while in the static test it is 0.25. Analysis on the characteristics of random drift was carried out and it is found that it can be treated as stable normally distributed random signal. Finally a corresponding Kalman filter was designed. The results indicated that after filtering the variance of random drift is reduced to 0.0282 26.4% of pre-filtering and the attitude angle error is reduced to 1.5 57.7% of pre-filtering. The above method can effectively compensate for the attitude angle error of MEMS gyro caused by random vibration. This study can be a reference to the application of low-cost MEMS gyro in aircraft navigation. (2012) Trans Tech Publications Switzerland.

Image registration based on Mexican-hat wavelets and pseudo-Zernike moments (EI CONFERENCE) 会议论文 OAI收割
2012 World Automation Congress, WAC 2012, June 24, 2012 - June 28, 2012, Puerto Vallarta, Mexico
作者: Liu Y.; Liu Y.; Liu Y.

收藏 | 浏览/下载：36/0 | 提交时间：2013/03/25

Image registration is a key technique in pattern recognition and image processing and it is widely used in many application areas such as computer vision remote sensing image fusion and object tracking. A method for image registration combining Mexican-hat wavelets and pseudo-Zernike moments is proposed. Firstly feature points are extracted using scale-interaction Mexican-hat wavelets in the reference image and sensed image respectively. Then pseudo-Zernike moments are used to match them and classical RANSAC used to eliminate the wrong matches. And then the well match points are used to estimate the best affine transform parameters by least squares minimization. At last the sensed image is transformed and resampled to accomplish the image registration. The experiments indicate that the proposed algorithm extracts feature points and matches them exactly and eliminates wrong matched points effectively and achieves nice registration results. 2012 TSI Press.