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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.  
Apoptosis induction and G2/M arrest of 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone from Rubia yunnanensis in human cervical cancer HeLa cells 期刊论文  OAI收割
PHARMAZIE, 2013, 卷号: 68, 期号: 4, 页码: 293-299
作者:  
Zeng, Guang-Zhi;  Fan, Jun-Ting;  Xu, Jun-Ju;  Li, Yan;  Tan, Ning-Hua
收藏  |  浏览/下载:44/0  |  提交时间:2015/05/14
2-Methyl-1,3,6-trihydroxy-9,10-anthraquinone (MTA)  one of the major components isolated from the traditional  Chinese medicine Rubia yunnanensis  exhibited inhibitory activity on the proliferation of several  human cancer cell lines. The results from an annexin V-FITC (fluoresein-5-isothiocyanate) apoptosis assay  and DNA content analysis showed that MTA exerted cytotoxicity via apoptosis induction and G2/M cell cycle  arrest in human cervical carcinoma HeLa cells. Further  MTA was found to induce apoptosis of HeLa cells  through the mitochondria-mediated pathway. It caused the translocation of Bax to the mitochondria and  release of cytochrome c into the cytosol  which caused the cleavage of caspase and poly(ADP-ribose)  polymerase and finally triggered the apoptosis. Furthermore  the p53/p21/Cdc2-cyclin B1 signaling was  found related to the G2/M arrest caused by MTA. The over-expression of p21 and down-expression of  cyclin B1 caused by MTA inactivated the Cdc2-cyclin B1 complex of G2/M checkpoint and finally caused  the G2/M arrest in HeLa cells. This study demonstrated that MTA is a potential anti-cancer component of  R. yunnanensis  a folk anti-cancer herb used in Yunnan  China.  
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:  
收藏  |  浏览/下载:37/0  |  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.  
Parameters estimation of BLDC motor for energy storage system (EI CONFERENCE) 会议论文  OAI收割
10th World Congress on Intelligent Control and Automation, WCICA 2012, July 6, 2012 - July 8, 2012, Beijing, China
Wu J.
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/25
Design of heliostats field for the scale of 1MW solar power tower plant (EI CONFERENCE) 会议论文  OAI收割
2012 Asia-Pacific Power and Energy Engineering Conference, APPEEC 2012, March 27, 2012 - March 29, 2012, Shanghai, China
作者:  
Zhang H.;  Wang Z.;  Wang Z.;  Zhang H.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
The development in basic technology and market strategy of solar thermal power techniques is booming rapidly due to the limited fossil resources and severe environmental problems all over the world. In this paper  the design method of heliostats field for the scale of 1MW solar power tower plant with latitude of 40.4N at the design point of the noon of spring equinox is introduced  which uses the multiplication of three efficiencies of cosine  atmospheric transmittance and intercept as the preliminary boundary limit to locate heliostats  while the spacing between heliostats is set not only for less shading and blocking  but also for the availability of installation and maintenance of heliostats. Furthermore  its optical performance tested by the software HFLD  is quite good  which has annual average efficiency of 71.36% and design point efficiency of 80%. 2012 IEEE.  
Information extraction from laser speckle patterns using wavelet entropy techniques (EI CONFERENCE) 会议论文  OAI收割
MIPPR 2011: Multispectral Image Acquisition, Processing, and Analysis, November 4, 2011 - November 6, 2011, Guilin, China
作者:  
Li X.-Z.;  Wang X.-J.
收藏  |  浏览/下载:39/0  |  提交时间:2013/03/25
A novel speckle patterns processing method is presented using multi-scale wavelet techniques. Laser speckle patterns generated from the sample contained abundant information. In this paper  we propose a method using wavelet entropy techniques to analyze the speckle patterns and exact the information on the sample surface. In our case  we used this approach to test the solar silicon cell surface profiles based on the sym8 orthogonal wavelet family. According different wavelet entropy values  the micro-structure of different solar silicon cell surfaces were comparative analyzed. Furthermore  we studied the AFM and reflective spectra of the wafer. Results show that the wavelet entropy speckle processing method is effective and accurate. And the experiment proved that this method is a useful tool to investigate the surface profile quality. 2011 SPIE.  
Multi-focus image fusion algorithm based on adaptive PCNN and wavelet transform (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Wu Z.-G.; Wang M.-J.; Han G.-L.
收藏  |  浏览/下载:78/0  |  提交时间:2013/03/25
Being an efficient method of information fusion  image fusion has been used in many fields such as machine vision  medical diagnosis  military applications and remote sensing.In this paper  Pulse Coupled Neural Network (PCNN) is introduced in this research field for its interesting properties in image processing  including segmentation  target recognition et al.  and a novel algorithm based on PCNN and Wavelet Transform for Multi-focus image fusion is proposed. First  the two original images are decomposed by wavelet transform. Then  based on the PCNN  a fusion rule in the Wavelet domain is given. This algorithm uses the wavelet coefficient in each frequency domain as the linking strength  so that its value can be chosen adaptively. Wavelet coefficients map to the range of image gray-scale. The output threshold function attenuates to minimum gray over time. Then all pixels of image get the ignition. So  the output of PCNN in each iteration time is ignition wavelet coefficients of threshold strength in different time. At this moment  the sequences of ignition of wavelet coefficients represent ignition timing of each neuron. The ignition timing of PCNN in each neuron is mapped to corresponding image gray-scale range  which is a picture of ignition timing mapping. Then it can judge the targets in the neuron are obvious features or not obvious. The fusion coefficients are decided by the compare-selection operator with the firing time gradient maps and the fusion image is reconstructed by wavelet inverse transform. Furthermore  by this algorithm  the threshold adjusting constant is estimated by appointed iteration number. Furthermore  In order to sufficient reflect order of the firing time  the threshold adjusting constant is estimated by appointed iteration number. So after the iteration achieved  each of the wavelet coefficient is activated. In order to verify the effectiveness of proposed rules  the experiments upon Multi-focus image are done. Moreover  comparative results of evaluating fusion quality are listed. The experimental results show that the method can effectively enhance the edge details and improve the spatial resolution of the image. 2011 SPIE.  
Reality Sim: A realistic environment for robot simulation platform of humanoid robot (EI CONFERENCE) 会议论文  OAI收割
5th International Conference on Automation, Robotics and Applications, ICARA 2011, December 6, 2011 - December 8, 2011, Wellington, New zealand
作者:  
Fu Y.
收藏  |  浏览/下载:38/0  |  提交时间:2013/03/25
As a virtual training  testing and evaluating environment  simulation platform becomes a significant component in Soccer Robot project. Nevertheless  the simulated environment in a simulation platform usually has a big gap with the realistic world. In order to solve this issue  we demonstrate a more realistic simulation system which is called Reality Sim with numerous real images. By this system  the computer vision code could be easily tested on simulation platform. For this purpose  previously  an image database with a large quantity of images recorded by camera pose is built. Furthermore  if the camera pose of an image is not included in the database  an interpolation algorithm is used to reconstruct a brand-new realistic image of that pose such that a realistic image could be provided on every robot camera pose. Our results show this system effectively simulates a more realistic environment for simulation platform. 2011 IEEE.  
Study of the neural network constitutive models for turfy soil with different decomposition degree (EI CONFERENCE) 会议论文  OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者:  
Nie L.
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/25
The turfy soil is of a special humus soil. The decomposition degree is the main factor on the physical and mechanical properties of turfy soil. To build the turfy soil constitutive model  there are a few shortages such as the calculation cumbersome and low accuracy for parameter value with the method of traditional models. Furthermore  those methods did not reflect the influence of strength that effected by decomposition degree of the turfy soil. In this paper  the relationship of stress-strain with different decomposition degrees of turfy soil was carried out through indoor tests. Based on above experimental results  an improved method  which divided into different zones according to different decomposition degrees of turfy soil and calculated combining with neural network constitutive model is put forward. The result shows that  the neural network of turfy soil has good fitting precision and good generalization ability. It can fully describe the influence of the turfy soil. 2011 IEEE.  
Effect of gimbal point displacement on optical axis pointing precision in an image seeker (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:39/0  |  提交时间:2013/03/25
A concentric glass spherical dome was usually chosen as the transparent window mounted in front of the optical lens in an image seeker. However  optical ray had to change its direction when propagating through the dome due to refraction unless passing through the center of the dome  which demanded gimbal point coincide with the center of the dome exactly. In fact  gimbal point displacement could not be eliminating due to fabrication  assembly and vibration  therefore the optical axis pointing error generated. In this paper  the effect of gimbal point displacement on optical axis pointing precision in an image seeker was analyzed  and the theoretical expression of the optical axis pointing error was derived based on geometric optics  and the error dynamics was explored by numerical. Take a visible light image seeker as a case  the thickness of concentric glass spherical dome was 8mm and the inner radius was 72mm  and the optical axis pointing errors varying dynamically with the look angle and the gimbal point displacement were shown in graph. When the gimbal displacement was 0.11mm  the maximum optical axis pointing error was 0.054mrad that is equal to the instantaneous field of view (IFOV) corresponding to the camera system whose focal length was 120mm and pixel size was 6.5m. Furthermore  with the gimbal displacement increasing  the optical axis pointing error increased linearly. The analyzed results provided a theoretical basis for the displacement range  which had to be limited strictly in the gimbal design process. 2011 IEEE.