Calculation of Power Consumption for a Helical-Screw Conveyer Transporting Bulk Materials

By 1940, a half dozen or so commercial or home-built transmission electron microscopes were in use for studies of the ultrastructure of matter. These operated at 30-60 kV and most pioneering microscopists were preoccupied with their search for electron transparent substrates to support dispersions of particulates or bacteria for TEM examination and did not contemplate studies of bulk materials. Metallurgist H. Mahl and other physical scientists, accustomed to examining etched, deformed or machined specimens by reflected light in the optical microscope, were also highly motivated to capitalize on the superior resolution of the electron microscope. Mahl originated several methods of preparing thin oxide or lacquer impressions of surfaces that were transparent in his 50 kV TEM. The utility of replication was recognized immediately and many variations on the theme, including two-step negative-positive replicas, soon appeared. Intense development of replica techniques slowed after 1955 but important advances still occur. The availability of 100 kV instruments, advent of thin film methods for metals and ceramics and microtoming of thin sections for biological specimens largely eliminated any need to resort to replicas.

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STEM Study of Surface Plasmon Excitation in Small Spherical Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133801 ◽

1990 ◽

Vol 48 (2) ◽

pp. 42-43

Author(s):

Daniel UGARTE

Keyword(s):

Energy Loss ◽

Spherical Particles ◽

Small Particles ◽

Bulk Materials ◽

Low Loss ◽

Plasmon Excitation ◽

Surface Modes ◽

Surface Plasmon Excitation ◽

Analytical Electron ◽

Analytical Electron Microscope

Small particles exhibit chemical and physical behaviors substantially different from bulk materials. This is due to the fact that boundary conditions can induce specific constraints on the observed properties. As an example, energy loss experiments carried out in an analytical electron microscope, constitute a powerful technique to investigate the excitation of collective surface modes (plasmons), which are modified in a limited size medium. In this work a STEM VG HB501 has been used to study the low energy loss spectrum (1-40 eV) of silicon spherical particles [1], and the spatial localization of the different modes has been analyzed through digitally acquired energy filtered images. This material and its oxides have been extensively studied and are very well characterized, because of their applications in microelectronics. These particles are thus ideal objects to test the validity of theories developed up to now.Typical EELS spectra in the low loss region are shown in fig. 2 and energy filtered images for the main spectral features in fig. 3.

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A Stationary Solution of High-Energy Electron Reflection (HEER) for An Arbitrary Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135472 ◽

1990 ◽

Vol 48 (2) ◽

pp. 374-375

Author(s):

YIQUN MA

Keyword(s):

Stationary Solution ◽

High Energy ◽

Bloch Wave ◽

Dynamical Theory ◽

High Energy Electron ◽

Bulk Materials ◽

Periodic Surface ◽

Electron Transmission ◽

Electron Reflection ◽

Long Time

For a long time, the development of dynamical theory for HEER has been stagnated for several reasons. Although the Bloch wave method is powerful for the understanding of physical insights of electron diffraction, particularly electron transmission diffraction, it is not readily available for the simulation of various surface imperfection in electron reflection diffraction since it is basically a method for bulk materials and perfect surface. When the multislice method due to Cowley & Moodie is used for electron reflection, the “edge effects” stand firmly in the way of reaching a stationary solution for HEER. The multislice method due to Maksym & Beeby is valid only for an 2-D periodic surface.Now, a method for solving stationary solution of HEER for an arbitrary surface is available, which is called the Edge Patching method in Multislice-Only mode (the EPMO method). The analytical basis for this method can be attributed to two important characters of HEER: 1) 2-D dependence of the wave fields and 2) the Picard iteractionlike character of multislice calculation due to Cowley and Moodie in the Bragg case.

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Compositional Tuning of Negative Differential Resistance in Bulk Silver Iodide Memristor

New Journal of Chemistry ◽

10.1039/d0nj05427e ◽

2020 ◽

Author(s):

SMITA GAJANAN NAIK ◽

Mohammad Hussain Kasim Rabinal

Keyword(s):

Power Consumption ◽

Negative Differential Resistance ◽

Silver Iodide ◽

Differential Resistance ◽

Fast Response ◽

Low Power Consumption ◽

Switching Effect ◽

Memory Switching ◽

Bulk Silver ◽

Emerging Memory

Electrical memory switching effect has received a great interest to develop emerging memory technology such as memristors. The high density, fast response, multi-bit storage and low power consumption are their...

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1 keV X-RAY ABSORPTION SPECTROSCOPY OF BULK MATERIALS BY ELECTRON YIELD MEASUREMENT

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1984262 ◽

1984 ◽

Vol 45 (C2) ◽

pp. C2-279-C2-280

Author(s):

J. M. Esteva ◽

R. C. Karnatak

Keyword(s):

Absorption Spectroscopy ◽

Bulk Materials ◽

X Ray ◽

Yield Measurement ◽

Electron Yield ◽

X Ray Absorption

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Optimal design of a high homogeneous and small-size shim coil for atomic spin gyroscope based on 0-1 linear programming

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209319 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 165-172

Author(s):

Dongge Deng ◽

Mingzhi Zhu ◽

Qiang Shu ◽

Baoxu Wang ◽

Fei Yang

Keyword(s):

Linear Programming ◽

Power Consumption ◽

Low Power ◽

Optimization Design ◽

Structural Parameters ◽

Axial Position ◽

Low Power Consumption ◽

Optimal Method ◽

Atomic Spin ◽

Shim Coil

It is necessary to develop a high homogeneous, low power consumption, high frequency and small-size shim coil for high precision and low-cost atomic spin gyroscope (ASG). To provide the shim coil, a multi-objective optimization design method is proposed. All structural parameters including the wire diameter are optimized. In addition to the homogeneity, the size of optimized coil, especially the axial position and winding number, is restricted to develop the small-size shim coil with low power consumption. The 0-1 linear programming is adopted in the optimal model to conveniently describe winding distributions. The branch and bound algorithm is used to solve this model. Theoretical optimization results show that the homogeneity of the optimized shim coil is several orders of magnitudes better than the same-size solenoid. A simulation experiment is also conducted. Experimental results show that optimization results are verified, and power consumption of the optimized coil is about half of the solenoid when providing the same uniform magnetic field. This indicates that the proposed optimal method is feasible to develop shim coil for ASG.

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Analysis of Characteristics of Halogen and LED Automobile Lamps

Light & Engineering ◽

10.33383/2019-067 ◽

2020 ◽

pp. 57-62

Author(s):

Olga Yu. Kovalenko ◽

Yulia A. Zhuravlyova

Keyword(s):

Power Consumption ◽

Flip Chip ◽

Weather Conditions ◽

Luminous Flux ◽

Luminous Efficacy ◽

Colour Temperature ◽

Study Results ◽

Calculation Results ◽

Mandatory Rules ◽

Halogen Lamps

This work contains analysis of characteristics of automobile lamps by Philips, KOITO, ETI flip chip LEDs, Osram, General Electric (GE), Gtinthebox, OSLAMPledbulbs with H1, H4, H7, H11 caps: luminous flux, luminous efficacy, correlated colour temperature. Characteristics of the studied samples are analysed before the operation of the lamps. The analysis of the calculation results allows us to make a conclusion that the values of correlated colour temperature of halogen lamps are close to the parameters declared by manufacturers. The analysis of the study results has shown that, based on actual values of correlated colour temperature, it is not advisable to use LED lamps in unfavourable weather conditions (such as rain, fog, snow). The results of the study demonstrate that there is a slight dispersion of actual values of luminous flux of halogen lamps by different manufacturers. Maximum variation between values of luminous flux of different lamps does not exceed 14 %. The analysis of the measurement results has shown that actual values of luminous flux of all halogen lamps comply with the mandatory rules specified in the UN/ECE Regulation No. 37 and luminous flux of LED lamps exceeds maximum allowable value by more than 8 %. Luminous efficacy of LED lamps is higher than that of halogen lamps: more than 82 lm/W and lower power consumption. The results of the measurements have shown that power consumption of a LED automobile lamp is lower than that of similar halogen lamps by 3 times and their luminous efficacy is higher by 5 times.

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