中国科学院机构知识库网格系统: 检索

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.

烟台牟平海洋牧场季节性低氧对大型底栖动物群落的生态效应 期刊论文 OAI收割
生物多样性, 2019, 卷号: 27, 期号: 2, 页码: 200-210
作者: 李宝泉

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收藏 | 浏览/下载：21/0 | 提交时间：2020/06/17

低氧群落结构群落恢复敏感种机会种 hypoxia community structure community recovery sensitive species opportunistic species Hypoxia is a common phenomenon in the world's oceans, especially in the shallow waters of coastal zones. Rates of hypoxia are increasing due to global climatic changes and anthropogenic activities. Hypoxia can cause mass mortality of marine animals and can have severe negative impacts on marine ecosystems. To better understand the effects of hypoxia on macrobenthic communities, a survey was carried out in the Muping Marine Ranch (Yantai) during June, August and September of 2016. Results showed that seasonal hypoxia led to changes in benthic community structure, especially in terms of species composition and dominant species. The dominant species were Polychaeta Lumbrinereis latreilli, Sternaspis scutata and Mollusca Endopleura lubrica in summer. The opportunistic species Lumbrinereis latreilli increased, whereas, sensitive species such as Leptomya minuta, Glycera chirori, Upogebia major, Pontocrates altamarimus, Eriopisella sechellensis decreased during the hypoxic period of August. Hypoxia also reduced biodiversity indices. The effect of hypoxia on abundance and biomass were not significant, mainly because of the increase in the opportunistic Lumbrinereis latreilli, which counteracted the decline in abundance and biomass of other species. Individual physiological tolerance to hypoxia was different among species. Lumbrinereis latreilli showed higher tolerance to hypoxia in dissolved oxygen (DO) = 1.0 mg/L compared to other species. Some sensitive species, such as Leptomya minuta, Upogebia major, Pontocrates altamarimus and Eriopisella sechellensis showed lower tolerance when DO < 2.5 mg/L. When DO increased to 2.5 mg/L, the macrobenthic community start to recover gradually. The recovery extent and time needed were closely related to the degree of seasonal hypoxia.

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)

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收藏 | 浏览/下载：27/0 | 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.

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：18/0 | 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.

Optimization analysis for radial support by finite elements method (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Intelligent System and Applied Material, GSAM 2012, January 13, 2012 - January 15, 2012, Taiyuan, Shanxi, China
作者: Wang Y.; Wang Y.; Wang Y.; Li C.; Wang Y.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

Primary mirror' surface figure is affected by supporting structure obviously. Especially for large-aperture telescope the surface figure is significant because of primary mirror' self-weight. For the requirement of the usage it's necessary to minimize the surface figure from self-weight by reasonable supporting scheme. The text optimized support point and force of radial support to minimize the surface figure by finite-element software. At the same time it studied the relationship between support point and counterweight to reduce the weight of support structure. At last it gave the optimal solution. (2012) Trans Tech Publications.

Design and fabrication of imaging optical systems with freeform surfaces (EI CONFERENCE) 会议论文 OAI收割
Current Developments in Lens Design and Optical Engineering XIII, August 13, 2012 - August 15, 2012, San Diego, CA, United states
作者: Zhang F.; Wang L.

收藏 | 浏览/下载：32/0 | 提交时间：2013/03/25

Freeform surfaces provide more degrees of freedom for design of optical systems and enhance the ability of compensation and correction aberrations. Freeform surfaces are of advantage to balance the unsymmetrical aberrations especially for the wide-field off-axis optical systems. This paper focus on an off-axis reflective optical system which focal length is 550mm F# is 6.5 and field of view (FOV) is 76. The system adopts some freeform surfaces. We discuss the problems we noticed in processes of design manufacture measurement and alignment and the solutions. At last the periodical research result and the expected performance are given. 2012 SPIE.

Compensation of moire fringe sinusoidal deviation in photoelectrical encoder based on tunable filter (EI CONFERENCE) 会议论文 OAI收割
2011 Symposium on Photonics and Optoelectronics, SOPO 2011, May 16, 2011 - May 18, 2011, Wuhan, China
作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

In order to improve the precision of the absolute photoelectrical encoder a compensating method is put forward which restrains the harmonics in moire fringe signal. After analyzing the relationship between the subdividing error and the sinusoidal index a low-pass digital filter which can make the moire signal satisfy the need of 1024 subdivision is designed. Considering with the fundamental frequency varies with the rotating speed of encoder the tunable filter is adopted whose cutoff frequency is calculated according to the coarse information of the encoder. The simulating results show that the proposed method can improve the sinusoidal index especially at high rotating speed. At last the compensating algorithm is implemented in the terminal of satellite optical communication which needs high resolution. The experimental results show indicate that the developed method is feasible. 2011 IEEE.

Development situation and trend of domestic and international aerial mapping camera (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
Ming L. W.; Xue L.; Hui C. X.; Jun L. Q.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

In the modern military affairs especially in the complex field the acquirement of real-time battlefield information and intelligence is getting more and more important most of this work is completed by aerial reconnaissance or aerial mapping equipment. Aerial mapping camera with time-sensitive and flexible features is playing an increasingly important role in modern warfare. With the development of technology aerial mapping camera has also gone through several generations gradually from film-based type to transmission type. The theory and composition of domestic and international typical aerial mapping camera is introduced from the development situation and trend in this paper. Finally with the domestic research status the development trend of aerial mapping camera is proposed. 2011 IEEE.

Fabrication of high-efficiency ultraviolet blazed gratings by use of direct Ar2-CHF3 ion-beam etching through a rectangular photoresist mask (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, May 24, 2011 - May 26, 2011, Beijing, China
Tan X.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

In ultraviolet spectroscopy groove irregularity and surface roughness of nanometer magnitude can cause a significant loss of diffraction efficiency. Therefore there is a constant need to improve the diffraction efficiency. A blazed grating can concentrate most of the light intensity into a desired diffraction order it is important to control the groove shape precisely so it is the optimum choice among gratings of different kinds of profile. As the operating wavelength of most UV spectral applications is less than 200 nm especially the blaze angle and the apical angle. We have presented a direct shaping method to fabricate EUV blazed gratings by using an ion-beam mixture of Ar+ and CHF2 +to etch K9 glass with a rectangular photoresist mask. With this method the required blaze angle is small we have succeeded in fabricating well-shaped UV blazed gratings with a 1200 line/mm groove density and 8.54 blaze angles and 1200 line/mm groove density and 11.68 blaze angles and the metrical efficiency is about 81% and 78%. The good performance of the gratings was verified by diffraction efficiency measurements. When one uses the etching model the conditions on the ion-beam grazing incident angle and the CHF3partial pressure should be noted. Besides since the etched groove shape depends on the aspect ratio of the photoresist mask ridge if we wish to fabricate larger gratings with this method we must improve the uniformity of the photoresist mask before ion-beam etching. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

The ship-borne infrared searching and tracking system based on the inertial platform (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Li Y.; Zhang H.; Zhang H.; Li Y.; Li Y.

收藏 | 浏览/下载：35/0 | 提交时间：2013/03/25

As a result of the radar system got interferenced or in the state of half silent it can cause the guided precision drop badly In the modern electronic warfare therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings but when interference is in the process of radar leading especially the electro-optical equipment is influenced by the roll pitch and yaw rotation it can affect the target appear outside of the field of optoelectronic devices for a long time so the infrared optoelectronic equipment can not exert the superiority and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking when the lead deviation of the radar is great. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).