中国科学院机构知识库网格系统: 检索

Gradient Structure-Induced Temperature Responsiveness in Styrene/Methyl Methacrylate Gradient Copolymers Micelles 期刊论文 OAI收割
macromolecular rapid communications, 2014, 卷号: 35, 期号: 3, 页码: 309-316
Zheng,Chao; Huang,Haiying; He,Tianbai

收藏 | 浏览/下载：24/0 | 提交时间：2015/10/15

In this work micelles are formed by gradient copolymer of styrene and methyl methacrylate in acetone-water mixture and their temperature responsiveness is investigated in a narrow range near room temperature. Three different kinds of structural transitions could be induced by temperature: unimers to micelle transition shrinkage/stretching of micelles and morphological transition from spherical micelles to vesicles. In addition a model analysis on the interface of gradient copolymer micelle is made to better understand these phenomena. It is found that both position and composition of the interface could alter in response to the change in temperature. According to the experiments and model analysis it is proposed that temperature responsiveness might be an intrinsic and universal property of gradient copolymer micelles which only originates from the gradient structure.

Structural Differences Between Cold- and Melt-Crystallized Poly(trimethylene terephthalate) Samples 期刊论文 OAI收割
APPLIED SPECTROSCOPY, 2013, 卷号: 67, 期号: 3, 页码: 307-313
作者: Chen, Zhen; Yan, Shouke

|

收藏 | 浏览/下载：21/0 | 提交时间：2019/04/09

Poly(Trimethylene Terephthalate) (Ptt) Fourier Transform Infrared Spectroscopy (Ft-ir) Crystallization Structure.

Structure and magnetic properties of (Al, Co) Co-doped ZnO thin films (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Materials Science and Nanotechnology, ICMSN 2012, November 16, 2012 - November 18, 2012, Guangzhou, China
Cao P.; Bai Y.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

In this study Zn0.99Co0.01Al0.015O thin film has been prepared by sol-gel method. The structural and magnetic properties of the sample were investigated. X-ray diffraction spectroscopy analyses indicate that the Co and Al codoping can not disturb the structure of ZnO. No additional peaks are observed in the Zn0.99Co0.01Al xO and Al3+ and Co2+ substitute for Zn 2+ without changing the wurtzite structure. The resistance measurements confirm that Al ions increase the free carriers concentration. Based on the above experiments we think the ferromagnetic behavior of the sample could not originate from Co nanoclusters. The presence of free carriers and localized d spins is a prerequisite for the appearance of ferromagnetism. As the result the carriers generated by Al doping is considered a main factor to induce the ferromagnetic phenomenon. (2013) Trans Tech Publications Switzerland.

Lightweight design of large scale theodolite's turntable based on topology optimization of continuum structure (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, 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 solve the problem that the weight of large scale theodolite's casting or steel plate welded structure is too heavy lightweight design of large scale turntable based on topology optimization of continuum structure is investigated. Topology optimization could have better optimization efficiency because it can provide the optimized distribution of material and gain optimized structure in conceptual design phase of the structural design. In order to obtain lightweight and high stiffness structure a truss turntable based on topology optimization of continuum structure is presented and the validity of this lightweight structure is examined by finite element analysis. Comparing to the traditional welding steel turntable the lightweight turntable without changing the static displacement can lose 386.48 kg(lightweight ratio is 26.7%) and its first-order natural frequency raises from 167.02Hz to 173.71Hz. Meanwhile in other aspects this turntable also has better performance than traditional structure. 2012 IEEE.

Effect of adding Cr on magnetic properties and metallic behavior in MnTe film (EI CONFERENCE) 会议论文 OAI收割
作者: Li J.; Li J.; Li J.

收藏 | 浏览/下载：44/0 | 提交时间：2013/03/25

Mn1 - xCrxTe films with x = 0 0.02 and 0.05 was synthesized by pulsed laser deposition and crystallize in hexagonal NiAs-type structure. The spin glass behavior predicted before by Monte Carlo calculation is observed in the MnTe film. This behavior is destroyed by adding Cr in the MnTe film. The temperature dependence of magnetization shows a sharp rise at around 66 K due to the magneto-elastic coupling. Metallic behavior is observed in the MnTe film in the temperature range 120-220 K which is ascribed to the magnetic ordering. The metallic behavior disappears with adding Cr because adding Cr ions destroys the magnetic ordering which is mediated by the sp-d exchange interaction between the Cr ions. 2012 Elsevier B.V.

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：25/0 | 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.

Study of horizontal shafting with spherical four-way structure (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
作者: Yang L.; Yang L.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

Altazimuth photoelectric theodolite level shaft U-type and T-type structure but with the expanding field of applications of photoelectric theodolite the horizontal shaft structure occur great changes. For example in the marine environment shipboard conditions the instrument has a waterproof corrosion-resistant easy maintenance and other functions while carrier-based optoelectronic devices from a single visible television configure the development of integrated infrared system and ranging system as one of the single-station measurement system due to the spherical structure has sufficient internal space exactly adapted to this need. In this paper the horizontal axis of a spherical four-way structure. From aspects of the spherical four-way split in the form and shafting design and finite element analysis of the detailed design. A spherical four-way horizontal axis system diameter 550mm weight 19kg sphere in the 40kg load the maximum deformation of 3.3m fully meet the requirements. The shaft of the structure of the shaking is less than 2 arc seconds the vibration test the re-examination instrument accuracy change is less than 1 arc seconds. Verify that the structure is stable and reliable. 2012 IEEE.

The electromagnetic compatibility design of restrained image transmission equipments (EI CONFERENCE) 会议论文 OAI收割
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
作者: Wang W.; Wang W.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

In order to improve the quality of image transmission this paper puts forward a box shielding method that could eliminate electromagnetic interference signal on image transmission equipments. At first this paper analyzes the shielding effectiveness of electromagnetic interference selects the qualified shielding material and designs the structure. After that it analyzes the descending of shielding effectiveness in the operational system and improves the equipments shielding effectiveness by means of the electromagnetic compatibility design that accords with electromagnetic compatibility norms. At last through the EMI radiometry this paper confirms that the equipments are in accordance with the design requirements of electromagnetic compatibility norms. (2012) Trans Tech Publications Switzerland.

Double inverted pendulum control based on three-loop PID and improved BP neural network (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Digital Manufacturing and Automation, ICDMA 2011, August 5, 2011 - August 7, 2011, Zhangjiajie, Hunan, China
作者: Fan Y.

收藏 | 浏览/下载：37/0 | 提交时间：2013/03/25

To deal with the defects of BP neural networks used in balance control of inverted pendulum such as longer train time and converging in partial minimum this article reaLizes the control of double inverted pendulum with improved BP algorithm of artificial neural networks(ANN) builds up a training model of test simulation and the BP network is 6-10-1 structure. Tansig function is used in hidden layer and PureLin function is used in output layer LM is used in training algorithm. The training data is acquried by three-loop PID algorithm. The model is learned and trained with Matlab calculating software and the simuLink simulation experiment results prove that improved BP algorithm for inverted pendulum control has higher precision better astringency and lower calculation. This algorithm has wide appLication on nonLinear control and robust control field in particular. 2011 IEEE.

Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
作者: Wang S.-R.; Lin G.-Y.; Yu L.

收藏 | 浏览/下载：36/0 | 提交时间：2013/03/25

Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.