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排序方式: 共有13条查询结果,搜索用时 22 毫秒
1.
Abstract Zinc phthalolocyanine photosensitized donor-acceptor systems for light energy conversion and for the design of photoelectrochemical molecular devices are presented. Covalently linked phthalocyanine complexes were incorporated in bilayer lipid membranes (BLM) and deposited on SnO2 transparent electrodes. Their photovoltages were measured and compared. It has been found that a more favorable orientation and closer proximity are attained in the diad compounds between the donor (phthalocyanine)-acceptor (anthraquinone) pair than in the reference compound for efficient light-induced charge separation and transfer. The triad compound is the best among all tested compounds. The decrease in the fluorescence yield and lifetime induced by quinones was examined and the apparent electron-transfer rate constants were calculated.  相似文献   
2.
采用多参考组态相互作用(MRCI)方法,结合aug-cc-pV6Z(AV6Z)基组,计算了C2+(X4Σg-,14Σu+)的势能曲线,计算过程中考虑了Davidson修正和相对论效应,并将结果外推至完备基组(CBS)的极限.基于得到的单点能量,用最小二乘法方法进行了Murrell-Sorbie函数拟合,得到了势能函数解析式(APEF).基于APEF,计算了C2+(X4Σg-,14Σu+)离子体系的离解能De,平衡核间距Re,光谱常数ωeeχe,Bee,结果与实验和其他理论计算值符合...  相似文献   
3.
A pinhole camera for imaging X-ray synchrotron radiation from a dipole magnet is now in operation at the Shanghai Synchrotron Radiation Facility (SSRF) storage ring. The electron beam size is derived by unfolding the radiation image and the point spread function (PSF) with deconvolution techniques. The performance of the pinhole is determined by the accuracy of the PSF measurement. This article will focus on a beam-based calibration scheme to measure the PSF system by varying the beam images with different quadrupole settings and fitting them with the corresponding theoretical beam sizes. Applying this method at SSRF, the PSF value of the pinhole is revised from 37 to 44 μm. The deviation in beam size between the theoretical value and the measured value is minimized to 4% after calibration. This optimization allows us to observe the horizontal disturbance due to injection down to as small as 0.5 μm.  相似文献   
4.
This paper clarifies the nonlinear and nonstationary characteristics of transient vibration of a single-disk rotor system on anisotropic supports passing through critical speed under limited energy supply. By analytical dynamics and Bogoliubov-Mitropolskii asymptotic method, the governing equations of motion of the system are reduced to a set of first order differential equations capable of numerical integral solution. The influences of gyroscopic effect of the rotor, external and internal damping as well as the initial phase angle of static unbalance on transient response are discussed.  相似文献   
5.
CTAB在硅胶表面吸附引起的润湿性变化和模拟驱油   总被引:3,自引:0,他引:3  
用椭圆偏振法测定溴代十六烷基三甲胺(CTAB)水溶液在光滑的二氧化硅膜片上的吸附,其结果符合两阶段模型,即在不同浓度下发生单分子层和近似双分子层的吸附,并与其表面润湿性变化的数据吻合.用改进的Washburn方程测量改性硅胶粉末的润湿性, 研究了CTAB水溶液在硅胶粉末表面上吸附引起的润湿性变化.并由此探讨了CTAB水溶液在硅胶粉末表面的润湿性,表面活性剂的临界胶束浓度(CMC)与表面含油粉末脱油率的关系,对在非超低界面张力条件下通过改变固/液界面润湿性提高原油采收率作了实验探讨.  相似文献   
6.
This paper reports the design and cold test of the cavity beam position monitor (CBPM) for SX-FEL to fulfill tile requirement of beam position measurement resolution of less than 1 p_m, even 0.1 btm. The CBPM was optimized by using a coupling slot to damp the TM010 mode in the output signal. Tile isolation of TM01o mode is about 117 dB, and the shunt impedance is about 200 ~@4.65 GHz with the quality factor 80 from MAFIA simulation and test result. A special antenna was designed to load power for reducing excitation of other modes in the cavity. The resulting output power of TM110 mode was about 90 mV/mm when the source was 6 dBm, and the accomplishable minimum voltage was about 200 btV. The resolution of the CBPM was about 0.1 btm from the linear fitting result based on the cold test.  相似文献   
7.
We perform the experiments to investigate in-situ phase fraction in a jet pump using the electrical resistance tomography (ERT) technique. A new jet pump with ERT sensors is designed to measure in-situ phase fraction and flow regime. The study is based on laboratory experiments that are carried out on a 50-mm vertical flow rig for various gas and liquid phase superficial velocities. The different flow patterns of gas liquid in the jet pump and vertical pipe are studied using the ERT technique. The results suggest that the ERT system can be used to successfully produce images of gas-liquid flow patterns with frames rates of 58 fps and the in-situ phase fraction with frame rates of 5 fps can be obtained. The visualizations of a rapid mixing process in the throat of a jet pump obtained in this work provide a reliable basis for theoretical study and optimal design of jet pumps.  相似文献   
8.
In this paper, the Riccati transfer matrix method and the component theory of forward and backward whirls are used to the eigenproblem of damped free whirling vibration of a flexible rotor with arbitrarily distributed mass on isotropic or anisotropic supports, with the gyroscopic effect taken into account to find out its critical speeds and corresponding vibrational shape functions. The generalized damped mode theory is developed and extended, which is employed in combination with the Bogoliubov-Mitropolskii asymptotic method to deduce two sets of first order differential equations to calculate the transient response of the rotor with limited power supply passing through its critical speeds in forward whirl and backward whirl respectively. The coupling phenomenon of the rotor through two neighboring critical speeds is also analyzed.  相似文献   
9.
Fluorescein ethyl ester as a model and four dyads of Fluorescein and Anthroic acid linked with different length spacer were synthesized and characterized. They were put in bilayer membrane and on SnO2 coated substrate, The photoinduced voltaic responses were observed and compared when fluorescein was excited using visible light. It was found that the dyads have higher responses than the model, and the dyad with a butylene spacer (n=4) has the highest response. The results and related mechanisms were discussed.  相似文献   
10.
DMPC与蛋白质在气-液界面上复合组装过程研究   总被引:2,自引:0,他引:2  
对磷脂DMPC与蛋白质(β-lactoglobulin,β-casein或humanserumalbumin)组成的复合单分子膜在压缩过程中的相变进行了研究,同时通过Brewster角显微镜观察了磷脂与蛋白质在空气-水界面处发生的自组装过程。发现当低表面压时在DMPC/β-casein,DMPC/humanserumalbumin和DMPC/β-lactoglobulin复合单分子膜上分别出现线状和块状微区,而在较高表面压时只有DMPC/β-casein体系出现钩状的微区。说明微区的形貌与蛋白质的种类及构象变化有关。  相似文献   
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