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近海环境中抗生素分析样品前处理技术的研究进展 期刊论文 OAI收割
色谱, 2020, 卷号: 38, 期号: 1, 页码: 95-103
作者: 吕敏; 陈令新

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抗生素近海前处理技术综述 antibiotics coastal pretreatment techniques review The widespread and massive usage of antibiotics for the prevention and treatment of diseases in human and animals have resulted in their continuous discharge into the environment, and finally, into the coastal environment through various pathways. Accumulation of antibiotics in aquatic organisms poses a great threat to ecological and human health, especially because it facilitates the generation and spread of bacterial resistance. Given the diverse range of antibiotics with various features, as well as their presence at low concentrations in the environment, it is imperative to develop pretreatment techniques for antibiotics in various matrices. In this paper, the pretreatment methods proposed in recent decades for antibiotics in coastal water, sediment, and biota are summarized, with emphasis on commonly used methods such as solid-phase extraction, solid-liquid extraction, matrix solid-phase dispersion, and QuEChERS. Additionally, the potential factors influencing the extraction performance and clean-up efficiency are analyzed. The advantages and disadvantages of the methods and their development are finally discussed.

Timing analysis of Swift J1658.2-4242's outburst in 2018 with Insight-HXMT, NICER and AstroSat 期刊论文 OAI收割
Journal of High Energy Astrophysics, 2019, 卷号: 24, 页码: 30-40
作者: HXMT

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Accretion accretion disks Black hole physics X-rays: binaries: Swift J1658.2-4242 Astrophysics - High Energy Astrophysical Phenomena Abstract: We present the observational results from a detailed timing analysis of the black hole candidate Swift J1658.2-4242 during its 2018 outburst with the observations of Hard X-ray Modulation Telescope (Insight-HXMT), Neutron Star Interior Composition Explorer (NICER) and AstroSat in 0.1-250 keV. The evolution of intensity, hardness and integrated fractional root mean square (rms) observed by Insight-HXMT and NICER are presented in this paper. Type-C quasi-periodic oscillations (QPOs) observed by NICER (0.8-3.5 Hz) and Insight-HXMT (1-1.6 Hz) are also reported in this work. The features of the QPOs are analyzed with an energy range of 0.5-50 keV. The relations between QPO frequency and other characteristics such as intensity, hardness and QPO rms are carefully studied. The timing and spectral properties indicate that Swift J1658.2-4242 is a black hole binary system. Besides, the rms spectra of the source calculated from the simultaneous observation of Insight-HXMT, NICER and AstroSat support the Lense-Thirring origin of the QPOs. The relation between QPO phase lag and the centroid frequency of Swift J1658.2-4242 reveals a near zero constant when < 4Hz and a soft phase lag at 6.68 Hz. This independence follows the same trend as the high inclination galactic black hole binaries such as MAXI J1659-152.

An analysis of first-time and repeat visitors to Korean national parks from 2007 and 2013 期刊论文 OAI收割
Journal of Mountain Science, 2017, 卷号: 14, 期号: 12, 页码: 2527-2539
作者: Yunseon CHOE; Michael A. SCHUETT; Kyu-Won SIM

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ThIs Paper ExamIned VIsiTors To Bukhansan NatiOnal Park In Korea Based On First-time And Repeat vIsitatiOn. Bukhansan NatiOnal Park Is Korea's Most Heavily vIsited NatiOnal Park With Annual vIsitatiOn Of Six milliOn VIsiTors In 2015. Data Used In ThIs Article Were Collected On-site In The Park In 2007 And 2013 By The Korea NatiOnal Park Service (Knps). The Study Variables Included Socio-demographics Travel Behavior Motivation And Satisfaction With Park Attributes Services And Facilities. Data Were Analyzed By Each Study Year For First-time And Repeat Visitors. Results Showed Significant Differences For Both First-time And Repeat Visitors.On Several Socio-demographic Travel Behavior And Motivation Variables Within Each Study Year. For Satisfaction With Park Attributes Facilities And Services First-time VisiTors Were Significantly Different From Repeat VisiTors On Seven Variables For Both Years. implicatiOns Are Given Regarding Programs And Services To Improve visiTor satisfactiOn And Sustain The Natural Cultural And HisTorical Resources At Bukhansan nAtional Park And Other nAtional Parks In Korea. Future Research Suggestions Are Provided To Learn More About visiTor Characteristics StAndards Of Quality And Preferences In The National Parks.

Rapid Micro-Patterning of a Conductive PANI/MWNTs-Polymer Composite Using an Optically-induced Electrokinetics Chip 会议论文 OAI收割
IEEE Nanotechnology Materials and Devices Conference (IEEE NMDC), Honolulu, HI, OCT 16-19, 2012
作者: Liu N(刘娜); Liang WF(梁文峰); Mai, John D.; Dong ZL(董再励); Li WJ(李文荣)

收藏 | 浏览/下载：36/0 | 提交时间：2013/12/26

A flexible, dynamically programmable and low-cost method applicable to micro-patterning of a conductive polymer/carbon nanotube composite solution is significant due to the potential applications in many areas. This paper demonstrates a new micro-patterning method for fabricating electrodes from a conductive polyaniline (PANI)/MWNT composite using an optically-induced electrokinetics (OEK) chip. This method quickly patterns flexible polymeric electrodes with different geometries when a square waveform signal with amplitudes from 16-20 Volts and frequencies from 20-30 kHz are applied. The geometric dimensions of the electrodes can be varied dynamically by controlling the size and exposure time of the light pattern. The surface morphology of electrodes patterned by this method is scanned by an atomic force microscope (AFM) and a scanning electron microscope (SEM) which show that the electrodes are uniform and continuous. Furthermore, the geometric dimensions and resistances of the electrodes are measured and analyzed. Experimental results reveal that the relationship between the resistance and geometries of the electrodes obey Ohm's law and the resistivity of the electrodes is about 0.03 Omega.m.

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：27/0 | 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.; Zhang J.; Wang X.

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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.

Structural amelioration of 920 nm optically pumped semiconductor vertical external-cavity surface emitting laser (OPS-VECSEL) (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Energy, Environment and Sustainable Development, EESD 2012, October 12, 2012 - October 14, 2012, Jilin, China
作者: Liu Y.; Liu Y.; Wang L.; Wang L.; Wang L.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

920 nm optically pumped semiconductor vertical external-cavity surface emitting laser (OPS-VECSEL) has an important application in laser display. We constructed and optimized a 920 nm OPS-VECSEL with active region of In0.09Ga0.91As quantum well (QW) system pumped by 808 nm laser diode module. By the finite element method self-consistent solutions of the semiconductor electronic and optical equations are realized to calculate the characteristics parameters of OPS-VECSEL. The performances of device especially the mode the threshold and the optical-optical translation efficiency were analyzed by dealing with different number of QWs (1 2 and 3) in one period QW depth barrier width the component and dimension of the non-absorption layer. We chose an improved structure of them. On this basis we ameliorated the number of QW periods and the simulation showed that in order to obtain high performance device the choice of the number of QW periods must be cautious. (2013) Trans Tech Publications Switzerland.

Finite element model and analysis for micro-cutting of aluminum alloy 7050-T7451 (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Machine Design and Manufacturing Engineering, ICMDME 2012, May 11, 2012 - May 12, 2012, Jeju Island, Korea, Republic of
作者: Zhou J.; Wang F.; Wang F.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

In this paper a finite element model with respect to actual state of micro-cutting is established by adopting software of ABAQUS/Explicit. Based on the FE model the cutting force and specific cutting force with various uncut depth of cut with different cutting edge radius are compared and then analyzed with regard to this simulation. In micro-cutting the nonlinear scaling phenomenon is more evident with the decreasing of uncut chip thickness. The likely explanations for the size effect in small uncut chip thickness are discussed in this paper. (2012) Trans Tech Publications Switzerland.

Method for improving transmission efficiency in 40Gbit/s system based on dispersion compensation (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Industrial Control and Electronics Engineering, ICICEE 2012, August 23, 2012 - August 25, 2012, Xi'an, China
Yu W.-J.; Wang R.-G.; Cheng P.; Zheng X.-F.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

In an effort to overcome the problem that the transmission efficiency is too low in 40Gbit/s system a method based on dispersion compensation is provided. Firstly the application background of 40Gbit/s system the key using technologies and the shortcomings and advantages of 40Gbit/s system are possessed. Secondly an application program of 40Gbit/s system based on dispersion compensation is given. At the same time this program is analyzed. Thirdly this program is compared with another program which has been widely used in 40Gbit/s system. Finally the compared results show that this program is able to improve the transmission efficiency apparently. 2012 IEEE.

Precision analysis of simulation systems with hardware-in-loop caused by performance of three-Axis virtual flight motion simulator (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Manufacturing Science and Technology, ICMST 2011, September 16, 2011 - September 18, 2011, Singapore, Singapore
Wang T.; Zhu M.-C.; Yin S.-L.; Jia H.-G.

收藏 | 浏览/下载：49/0 | 提交时间：2013/03/25

Simulation systems with hardware-in-loop are composed by three-Axis virtual flight motion simulator simulation computer load torque simulator and visual simulation systems. Three-Axis Virtual Flight Motion Simulator are used to simulate the attitude of missile in simulation system with hardware-in-loop so its performance influenced the result of simulation directly. This paper mainly analyzed the factors which influenced the performance of a three-Axis virtual flight motion simulator which we are used now in the lab then analyzed the entire simulation system's error caused by these factors through numerical simulation method. By analysis we can see that bandwidth is the main factor influenced the precision of simulation systems with hardware-in-loop mechanical device installation error and measurement error may also cause some errors of the systems at the same time.