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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
  |  收藏  |  浏览/下载：110/0  |  提交时间：2020/07/08
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.  
Comparison of simulated backgrounds with in-orbit observations for HE, ME, and LE onboard Insight-HXMT 期刊论文  OAI收割
Astrophysics and Space Science, 2020, 卷号: 365, 页码: 158
作者:  HXMT
  |  收藏  |  浏览/下载：50/0  |  提交时间：2022/02/08
Insight-HXMT  Geant4 simulation  Background observation  Astrophysics  - Instrumentation and Methods for Astrophysics  Abstract: Insight-HXMT, the first X-ray astronomical satellite in China, aims to reveal new sources in the Galaxy and to study fundamental physics of X-ray binaries from 1 to 250 keV. It has three collimated telescopes, the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME), and the Low Energy X-ray telescope (LE). Before the launch, in-orbit backgrounds of these three telescopes had been estimated through Geant4 simulation, in order to investigate the instrument performance and the achievement of scientific goals. In this work, these simulated backgrounds are compared with in-orbit observations. Good agreements are shown for all three telescopes. For HE, (1) the deviation of the simulated background rate after two years of operation in space is 5 % from the observation  (2) the total background spectrum and the relative abundance of the 67 keV line show long-term increases both in simulations and observations. For ME, (1) the deviation of simulated background rate is within 15 % from the observation, and (2) there are no obvious long-term increase features in the background spectra of simulations and observations. For LE, the background level given by simulations is also consistent with observations. The consistencies of these comparisons validate that the Insight-HXMT mass model, i.e., space environment components and models adopted, physics processes selected, and detector constructions built, is reasonable. However, the line features at 7.5 and 8.0 keV, which are obvious in the observed spectra of LE, are not evident in simulations. This might result from uncertainties in the LE constructions.  
Worth-based choice: giving an offered smaller pear an even greater fictional value 期刊论文  OAI收割
JOURNAL OF PACIFIC RIM PSYCHOLOGY, 2019, 卷号: 13, 页码: 16
作者:  Zheng, Yu;  Shen, Si-Chu;  Xu, Ming-Xing;  Rao, Li-Lin;  Li, Shu
  |  收藏  |  浏览/下载：77/0  |  提交时间：2019/05/20
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
  |  收藏  |  浏览/下载：140/0  |  提交时间：2017/12/07
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.  
Mid-late Pleistocene glacial evolution in the Grove Mountains, East Antarctica, constraints from cosmogenic Be-10 surface exposure dating of glacial erratic cobbles 期刊论文  OAI收割
QUATERNARY SCIENCE REVIEWS, 2016, 卷号: 145, 期号: 0, 页码: 71-81
作者:  Dong, GC (Dong, Guocheng);  Huang, FX (Huang, Feixin);  Caffee, MW (Caffee, Marc W.);  Huang, FX;  Yi, CL (Yi, Chaolu)
  |  收藏  |  浏览/下载：29/0  |  提交时间：2017/09/26
Glacial HisTories From The East Antarctic Ice Sheet (Eais) Provide Keys To UnderstAndIng Correlations Between The Eats And Global Climate. They Are Especially Helpful In The Assessment Of Global Sea Level Change  And As a Means Of Quantifying The Magnitude Of pAst Glacial Activity And The RAte At Which Ice Responded To climAte Change. Given The Significance Of Eais Glacial hisTories  It Is Imperative That More Glacial Chronologic Data For thIs Region Be Obtained  Especially For The Mid-to-lAte Pleistocene. We Report Cosmogenic Be-10 Surface Exposure DAtIng Results From Glacially Transported Cobbles Embedded In Blue-ice moraIne MAterial At Mount hardIng  The Grove Mountains  Eais. Forty Exotic Cobbles Sampled AlOng Two PrOfiles (a And b) On This Blue-ice MoraIne Present Apparent Exposure-ages RangIng From 7.2 To 542.2 Ka. We Explore This Scattered Dataset By UsIng PrIncipal compOnent Analysis (Pca) To Identify Statistically Significant Trends In The Data. We Identify a correlatiOn betWeen Exposure-age And Distance Of The Cobbles From Mount hardIng. In prOfile a  Cobbles Further From Mount HardIng Yield Older Exposure-ages Than Those That Are Relatively Close. In Profile b  Cobbles Closer To Mount HardIng Are Found To Have Relatively Older Exposure-ages. In Term Of Glacial hisTory We Suggest That The Direction Of Ice Flow Changed durIng The Period From Similar To 60 To 200 Ka  And That Multiple Glacial Fluctuations Occurred In The Mid-late Pleistocene. (c) 2016 Elsevier Ltd. All Rights Reserved.  
Error analysis of the micro temperature control system (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Measurement, Instrumentation and Automation, ICMIA 2012, September 15, 2012 - September 16, 2012, Guangzhou, China
Han Z.; Song K.
收藏  |  浏览/下载：48/0  |  提交时间：2013/03/25
Accuracy synthesis of a 3-RPS parallel robot based on manufacturing costs (EI CONFERENCE) 会议论文  OAI收割
31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China
Yao T.-K.; Xi Z.; Feng Z.; Zhang L.-M.; Yong W.
收藏  |  浏览/下载：32/0  |  提交时间：2013/03/25
Pose accuracy is an important issue for parallel robot being used as mirror supporting system of telescope. One challenging topic is the accuracy synthesis which deals with the optimal design of the manufacturing and assembling tolerances of each component under the given pose accuracy. First  the error model of the 3-RPS parallel robot is built based on total derivation of the kinematic equations. And the error variable of each spherical or rotate joint can be expressed as a single boundary error parameter but not three independent position parameters. Then  the accuracy synthesis model is formulated taking the manufacturing costs as the optimization objective and the accuracy requirements as the constraint condition. Finally  the genetic algorithm is used to solve the optimization problem and a simulation example is given. The results show that the accuracy synthesis method based on manufacturing costs can satisfy the need of pose accuracy and is better for engineering application than the method based on error sensitivity. 2012 Chinese Assoc of Automati.  
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
Research on the torque characteristic of disc micromotor on axial magnetic field (EI CONFERENCE) 会议论文  OAI收割
2012 2nd International Conference on Consumer Electronics, Communications and Networks, CECNet 2012, April 21, 2012 - April 23, 2012, Three Gorges, China
Liu B.
收藏  |  浏览/下载：53/0  |  提交时间：2013/03/25
In order to increase the electromagnetic torque density of micromotor with axial magnetic field  numerical analysis of permanent magnetic field and electromagnetic torque were deduced and the key factors of increasing torque density of micromotor was obtained. The numerical analysis of three-dimensional magnetic field in air gap produced by spliced sector permanent magnetic poles is done  and the way of improving flux density and permanent magnet use efficiency are given through investigating the influence of magnet thickness  height of air gap and pole interval rate and other parameters to air gap flux density and leakage flux. Based on the test of axial magnetic field and torque characteristic of micromotor  the analysis of micromotor magnetic field and calculation of torque are verified  meanwhile using the plane stator with 0.7mm thickness assemble micromotor having minimum air gap height of 1mm and its torque constant up to 3.8mNm/A. 2012 IEEE.  
Correction of baseline drifts due to the pressure changes between attenuated total reflection prism and human skin for noninvasive blood glucose sensing with Fourier Transform infrared spectroscopy (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Smart Materials and Nanotechnology in Engineering, SMNE 2011, September 17, 2011 - September 18, 2011, Wuhan, China
作者:  Wang D.
收藏  |  浏览/下载：48/0  |  提交时间：2013/03/25