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101.
Complex scattering amplitudes are used to calculate the phase contrast of colloidal gold particles. Comparison of measurements of the phase contrast intensity at the centre of the gold particle as a function of defocus for unfiltered and zero-loss filtered images demonstrates the increase in phase contrast achieved by zero-loss filtering even for a thick carbon substrate film. The granulation of amorphous germanium films is measured by the spatial rms (root mean square) values of image intensity in a defocus series. 相似文献
102.
Hiromasa Higasa Ryoichi Takahata Hiroshi Imaizumi Kenzo Miya 《Electrical Engineering in Japan》1996,116(3):96-106
A high-temperature superconductor YBa2Cu3O7-x with strong pinning force has allowed stable magnetic suspension with no control to be developed. Two types of superconducting magnetic bearings (SMB) using YBCO and permanent magnet were assembled. The two types are radial and axial. The dynamic stiffness of each SMB as it was cooled down under a magnetic field by liquid nitrogen was measured both radially and axially. As a result, it was found that the spring constants of these SMBs were almost as large as a practically desirable value; however, their damping coefficients were lower than the practical level. These findings are useful as one of the data bases for development of an optimum SMB design to support the weight of rotors in an axial direction. 相似文献
103.
Visually perceiving an action may activate corresponding motor programs. This automatic motor activation can occur both for higher level (i.e., the goal of an action) and for lower level (i.e., the specific effector with which it is executed) aspects of an action. The authors used a tool-use action paradigm to experimentally dissociate priming effects for observing the target, the movement, or the target-to-movement mapping of a tool-use action. In 3 experiments, participants took turns in acting, observing the tool-use action of another person in trial n-1, and executing an action in trial n. Trial transitions from n-1 to n were manipulated in 4 conditions with (a) mapping repeated and movement and target changed, (b) target repeated and movement and mapping changed, (c) movement repeated and target and mapping changed, or (d) all components repeated. Results indicate priming effects for repeating the target-to-movement mapping (i.e., the action rule) of a tool-use action and suggest that a rather abstract action schema is activated during action observation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
A series of nanocomposite thin films, composed of Nd2Fe14B and α-Fe, has been prepared by DC-magnetron sputtering combined ion beam sputtering onto Si (100) substrates. The effects of post annealing on the microstructure and magnetic properties of [NdFeB/α-Fe/NdFeB]-type thin films have been investigated. The X-ray diffraction (XRD) study showed that annealing of the films for 30min at temperatures 550,600,650,700℃ resulted in the appearance of diffraction peaks, characteristic for Nd2Fe14B tetragonal structure, α-Fe and Nd2O3 phases. The investigation using the Vibrating Sample Magnetometer (VSM) with a maximum applied field of 2 T indicated that with the increase of the annealing temperature, the magnetic properties of the multilayer films were improved and reached peak value at 650℃ (Hci=41.72kA·m-1, Mr/Ms=0.4, (BH)max=30.35kJ·m-3), after which the magnetic properties were decreased greatly. Along with the increase of the thickness of α-Fe layer from Tα-Fe16nm, the coercivity Hci, saturation magnetization Ms, and remanence ratio Mr/Ms all declined. As the Atomic Force Microscope (AFM) indicated, after being annealed at 650℃ for 30min, the sample was showed fine surface morphology with grain size 60nm≤dα-Fe≤80nm and 100nm≤dNdFeB≤150nm. 相似文献
105.
The structural change of diamond induced by hydrogen plasma exposure at room temperature, and its thermal stability, were investigated using electron spin resonance (ESR), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) techniques. ESR observation revealed that it gave rise to a highly defective structure (spin concentration of 1020 cm− 3), which is very similar to the structure of hydrogenated amorphous carbon (a-C : H) confirmed by XPS and FTIR. Post-annealing was also carried out to clarify the thermal stability of the defects. The number of spin centers decreased with increasing annealing temperature, and eventually, the defective structure changed to a graphitic one by annealing at 800 °C. 相似文献
106.
采用大电流交流脉冲对非晶Fe78B13Si9合金进行了去应力退火。初步探讨了电脉冲加热对加热速率和该合金内应力释放、退火脆化以及最终软磁性影响的基本规律。结果表明:电脉冲加热可以得到远高于常规退火的加热速率,选择合适工艺参数可使非晶合金内应力释放90%,软磁性(H_c和B_s)达常规退火后的95%以上,与此同时使合金的延性(断裂应变ε_f)维持在0.9以上,从而有望实现非晶合金磁性与延性的合理配合。 相似文献
107.
本文主要阐述使用红外热象仪检测运行中的电力设备所发现的问题。文中通过若干实例介绍了用红外热象仪检测带电运行的发电机、电容器及连接头,并查出带有严重缺陷的部位,从而避免事故发生。 相似文献
108.
Allan Rogerson 《Journal of Nondestructive Evaluation》1996,15(3-4):93-99
This paper reviews available information on the state of practice of inservice material property monitoring performed in European energy industries. Current practice includes a range of standard nondestructive testing and monitoring methods, improved remote sampling and surveillance specimen testing, and new monitoring techniques which are emerging from ongoing development programs. These new technologies include ultrasonic, positron annihilation, neutron diffraction, and magnetic techniques. 相似文献
109.
A. N. Palagushkin S. A. Prokopenko A. P. Sergeev A. N. Arlamenkov 《Optical Memory & Neural Networks》2007,16(4):288-294
The results of experimental definition of optical parameters of silver nanolayers by the method of surface plasmon resonance
(SPR) are described. The goniometric installation for measurement of angular dependences of reflection of light by layered
nanosructures at the attenuated internal reflection (angular spectrum of reflection) is designed. Calculation of optical parameters
of nanolayers is executed taking into account the form of a curve of tin angular spectrum of reflection.
The text was submitted by the authors in English. 相似文献
110.