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烟台夹河口外柱状沉积物还原性无机硫、活性铁的变化特征及其相互关系 期刊论文  OAI收割
海洋科学, 2018, 卷号: 42, 期号: 8, 页码: 90-97
作者:  
姜明;  赵国强;  李兆冉;  盛彦清
  |  收藏  |  浏览/下载:27/0  |  提交时间:2020/07/08
还原性无机硫  活性铁  深层柱状沉积物  硫化度  矿化度  Reduced inorganic sulfur  Reactive iron  Deep core sediments  Degree of pyritization  Degree of sulfidity  The distribution characteristics and coupling mechanism of reduced inorganic sulfur (RIS)and reactive iron in marine core sediments are closely related to the evolution of environment quality.In this study,an improved cold diffusion method and hydrochloric acid extraction method were applied to the acid-volatile sulfur (AVS),pyrite sulfur (CRS),elemental sulfur (ES),and reactive iron [Fe (Ⅱ)and Fe (III)] analyses.The distribution characteristics and coupling mechanism of S and Fe were investigated based on a core sediment 4 meters deep collected in the northern sea area of the mouth of Jiahe River,Yantai.The results showed that the RIS in sediments was dominated by CRS,followed by AVS and ES.The content of AVS presented a narrow range with depth,whereas the CRS and ES were higher at the top and bottom layers than the middle layer  reactive iron was dominated by Fe (II),which increased with depth,while Fe (Ⅲ)gradually decreased with depth.Most of the Fe (III)was reduced to the disssolved Fe(II),which was combined with the soluble H_2S of the sulfate-reducing bacteria to produce CRS and ES in the deep layer,resulting in their accumulation at the bottom of core sediments.Furthermore,this study showed that reactive iron was not a limiting factor for the accumulation of RIS with lower degree of pyritization and degree of sulfidity.  
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
收藏  |  浏览/下载:34/0  |  提交时间:2015/10/20
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.  
Reagentless near-infrared determination of cholesterol in undiluted human serum using interval partial least square (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
Gao H.; Lu Q.; Huang F.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
In order to determination of cholesterol in human serum with no reagent using nearinfrared (NIR) spectroscopy. Interval partial least square (iPLS) was proposed as an effective variable selection approach for multivariate calibration. For this purpose  an independent sample set was employed to evaluate the prediction ability of the resulting model. The spectrum was split into different interval. Then  the informative region of cholesterol (1688-1760nm)  in which the PLS model has a low RMSEP with 0.241mmol/L and a high R with 0.975  is selected with 23 intervals. The results indicate that  the informative region of cholesterol can be obtained by iPLS and applied to design the simpler reagentless NIR instruments for inexpensive cholesterol measurement in future. (2012) Trans Tech Publications  Switzerland.  
Influence of high temperature annealing in nitrogen on upconversion luminescence of -NaYF4: Yb3+, Er3+ hexagonal sub-microplates (EI CONFERENCE) 会议论文  OAI收割
2012 International conference on Function Materials and Nanotechnology, FMN 2012, May 19, 2012 - May 20, 2012, Zhengzhou, China
作者:  
Zhao J.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
The pure -NaYF4: Yb3+  Er3+ hexagonal sub-microplates were successfully prepared by the combination of coprecipitation and hydrothermal methods using sodium citrate as chelator. The size of them is about 600 nm 400 nm (side length thickness). The obtained sample was divided into two parts and one of them was annealed in nitrogen at 300 C for 2 hours. The crystal structure of the -NaYF4: Yb3+  Er3+ hexagonal sub-microplates before and after annealing treatment is hexagonal phase. Under the excitation of 980 nm diode laser  the upconversion luminescence intensity the sample after annealing is much stronger than that of the sample without annealing treatment. High temperature annealing process improved the crystallization of the sample  resulting in the decrease of the nonradiative relaxation and the enhancement of the upconversion luminescence. (2012) Trans Tech Publications  Switzerland.  
Rapid cell separation in double spiral microfluidic channels 会议论文  OAI收割
23rd International Congress of Theoretical and Applied Mechanics, 中国北京/Beijing, China, 2012-08-19
作者:  
Liu C;  Sun JS;  Jiang XY;  Hu GQ(胡国庆)
收藏  |  浏览/下载:23/0  |  提交时间:2014/04/02
Design of reimaging F/1.0 long-wavelength infrared optical system (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:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:36/0  |  提交时间:2013/03/25
A reimaging F/1.0 long-wavelength infrared optical system is proposed. The design has a flexible opto-mechanical layout. The design process is as follows. Firstly  the catadioptric reimaging system consists of two reflecting mirrors and a relay lenses. Two reflecting mirrors make up of the first imaging system and are therefore free of chromatic aberrations  while low dispersion lenses were used in the reimaging system  so the optical system do not need achromatic design for a high image quality. Then  to correct high-order aberrations resulting from large relative aperture  more parameters need to be used with aspheric or diffractive surfaces due to modern optic technology development. Here  aspheric is selected for easily manufacture. Finally  the design is completed with the help of ZEMAX software. The effective focal length of the objective is 120mm and the field of view (FOV) is 4. The simulated final design shows adequate image quality and the modulation transfer function (MTF) is close to diffraction limit. The effect of the surrounding environmental temperature is analyzed using the concept of thermal defocusing  and the thermal compensation is discussed. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
High resolution gray-scale modulation method based on linear superposition for LED displays (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Control, Automation and Systems Engineering, CASE 2011, July 30, 2011 - July 31, 2011, Singapore, Singapore
Feng Y.; Xu X.; Miao C.; Ding T.
收藏  |  浏览/下载:12/0  |  提交时间:2013/03/25
Design of stable image platform on airborne camera (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China
作者:  
Yang L.;  Yang L.
收藏  |  浏览/下载:16/0  |  提交时间:2013/03/25
Modulation transfer function resulting from random vibration was analyzed. To conclude that the effect of angular displacement was the major factor. Allowable MTF degradation was represented  and 34dB reduction was achieved at frequency of 100HZ. With the help of MSC.ADAMS simulation software  and convert allowable MTF degradation into stable system design parameters  simulated curve proves correct for isolator  which can guide perfect design for stabilization system. Based on the spatial mechanism and translational principle of parallelogram  and the irrotational displacement mechanism was tested by optical method  an irrotational displacement isolator was developed. It can meet the requirements of irrotational displacement and damp. An instance was given  coupled angle is less than 8?  it can satisfy the demand of aerial imaging. (2011) Trans Tech Publications.  
Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文  OAI收割
Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise  for a seeker electro-driven with a concentric glass dome  the large errors will decrease the picking  pointing  and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure  manufacture  installation and vibration coming from working environment. In this paper  the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case  the diameter is 120mm  and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker  and at the same time  the errors resulting from installation were considered too. Based on calculating  the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However  the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper  and finally  the maximum gimbal displacement error reduced to 0.1mm  which is acceptable corresponding to the picking  pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Integrated intensity, orientation code and spatial information for robust tracking (EI CONFERENCE) 会议论文  OAI收割
2007 2nd IEEE Conference on Industrial Electronics and Applications, ICIEA 2007, May 23, 2007 - May 25, 2007, Harbin, 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
real-time tracking is an important topic in computer vision. Conventional single cue algorithms typically fail outside limited tracking conditions. Integration of multimodal visual cues with complementary failure modes allows tracking to continue despite losing individual cues. In this paper  we combine intensity  orientation codes and special information to form a new intensity-orientation codes-special (IOS) feature to represent the target. The intensity feature is not affected by the shape variance of object and has good stability. Orientation codes matching is robust for searching object in cluttered environments even in the cases of illumination fluctuations resulting from shadowing or highlighting  etc The spatial locations of the pixels are used which allow us to take into account the spatial information which is lost in traditional histogram. Histograms of intensity  orientation codes and spatial information are employed for represent the target Mean shift algorithm is a nonparametric density estimation method. The fast and optimal mode matching can be achieved by this method. In order to reduce the compute time  we use the mean shift procedure to reach the target localization. Experiment results show that the new method can successfully cope with clutter  partial occlusions  illumination change  and target variations such as scale and rotation. The computational complexity is very low. If the size of the target is 3628 pixels  it only needs 12ms to complete the method. 2007 IEEE.