High-efficiency transmissive invisibility cloaking based on all-dielectric multilayer frame structure metasurfaces

Introduction: For technical renovation of the thermal plant, one frame structure workshop of 50,000 m2 construction area and one reinforcement concrete chimney of 150m height shall be demolished by blasting in the same time. The engineering environment is very complicated and the accommodation space for the structures collapse is limited. Therefore, the collapse sequence, direction, scope of the structures must be accurately controlled to ensure the safe operation of the adjacent generator unit and transformer station. Methods: By taking technical measures of theoretical analysis and numerical simulation etc., as well as research on structures collapse process and initiation system, it puts forward the technology of bidirectional folded collapse of the workshop and it uniquely adopts the initiation system that combined with “half-second delay inside drilling” and “millisecond delay outside drilling”. Results and Conclusion: Additionally, by using of the integrated vibration reduction technology in combination of the blasting ruins, buffer ditch and damping ditch, it has safely accomplished the blasting demolition work in high efficiency. Besides the blasting demolition vibration signal is collected and analyzed. The success of the blasting demolition will become valuable reference to other similar works.

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The SkyTrough™ Parabolic Trough Solar Collector

ASME 2009 3rd International Conference on Energy Sustainability, Volume 2 ◽

10.1115/es2009-90090 ◽

2009 ◽

Cited By ~ 6

Author(s):

Adrian Farr ◽

Randy Gee

Keyword(s):

Solar Collector ◽

High Efficiency ◽

Low Cost ◽

Frame Structure ◽

Component Part ◽

Parabolic Trough ◽

Actuation System ◽

Inrush Currents ◽

Parabolic Trough Solar Collector ◽

Utility Scale

The SkyTrough™ is a new high-efficiency parabolic trough solar collector that has been designed with features to reduce capital cost, shorten installation time, and reduce O&M cost. This collector builds on the excellent success of prior generation utility-scale parabolic trough designs, but incorporates several engineering and material innovations, listed below. 1. Lightweight, low cost, unbreakable non-glass reflectors using ReflecTech® Mirror Film with reflectance equal to silvered glass mirrors — and easy to install and replace, 2. Large aperture area parabolic trough module with more than double the aperture area of the Nevada Solar One (NSO) module, 3. Longer linear receiver (SCHOTT PTR™80) utilized to match the larger aperture width SkyTrough, 4. Aluminum space frame structure that is considerably lighter per unit of aperture area compared to NSO, 5. Total component “part count” that is considerably reduced per unit of aperture area, yielding a shorter assembly time per unit of aperture than the NSO modules, 6. Hydraulic-based rotary actuation system that provides built-in “stow” locking capability and higher torque capability compared to NSO, 7. SkyTrakker™ control system reduces inrush currents and reduces parasitic power consumption associated with collector sun tracking.

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Seismic Performance of an Efficient Scissor-Jack-Damper Configuration

Shock and Vibration ◽

10.1155/2020/2403640 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Lihua Zhu ◽

Pengyu Guo ◽

Chenglong Hua ◽

Shiyu Shan

Keyword(s):

Mechanical Behavior ◽

Seismic Performance ◽

High Efficiency ◽

Steel Frame ◽

Earthquake Damage ◽

Frame Structure ◽

Magnification Factor ◽

Practical Engineering ◽

Steel Frame Structure ◽

Damping Systems

Energy-dissipating or damping systems have been widely used in new and retrofitted structures for reducing earthquake damage to structural frames. Most damping devices were installed using diagonal or chevronbrace configurations, until the development of toggle-brace and scissor-jack configurations. This paper presents a modified scissor-jack-damper configuration with substantially improved efficiency. The mechanical behavior of the efficient scissor-jack-damper configuration is analyzed theoretically, and a formula for the displacement magnification factor of the configuration is proposed. A steel-frame specimen installed with the efficient scissor-jack-damper configuration was tested to verify the accuracy of the formula. The seismic responses of an uncontrolled steel-frame structure and of two controlled structures, installed with a diagonal brace and efficient scissor-jack-damper configurations, were analyzed using SAP2000. The high efficiency of the proposed scissor-jack-damper configuration is thus verified for practical engineering situations.

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Preparation and strengthening mechanisms of in-situ HF catalyzed highly porous mullite with whisker frame structure

Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University ◽

10.1051/jnwpu/20213910208 ◽

2021 ◽

Vol 39 (1) ◽

pp. 208-215

Author(s):

Haihong Zhang ◽

Qi Wang ◽

Jinhai Wang ◽

Fangli Yu ◽

Jianjiang Tang ◽

...

Keyword(s):

Porous Materials ◽

High Efficiency ◽

Sol Gel ◽

High Strength ◽

Transition Process ◽

Lap Joints ◽

Frame Structure ◽

High Porosity ◽

Porous Mullite

Using HF as catalyst and based on sol-gel chemical precursor powder molding and sintering process, porous mullite with whisker frame structure was in-situ synthesized in the blank body. Due to the high efficiency catalysis of HF, this structure has both of high porosity and high strength. The effects of HF addition and sintering temperature on the formation of mullite whisker frame, phase transition process, porosity and strength of porous materials were discussed, and the optimal process parameters were determined. The mechanism of strengthening the porous materials was preliminary analyzed, and under the catalysis of HF, the close connection between whisker frame lap joints was formed. When the porosity of mullite is up to 83.22%, the compressive strength of can reach 16.48 MPa.

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Microcalorimeters for X-Ray Spectroscopy

International Astronomical Union Colloquium ◽

10.1017/s0252921100107365 ◽

1988 ◽

Vol 102 ◽

pp. 41

Author(s):

E. Silver ◽

C. Hailey ◽

S. Labov ◽

N. Madden ◽

D. Landis ◽

...

Keyword(s):

High Resolution ◽

High Efficiency ◽

Thermal Response ◽

Low Noise ◽

High Resolution Spectroscopy ◽

Superconducting Transition ◽

Sapphire Substrates ◽

Laboratory Plasmas ◽

Adiabatic Demagnetization ◽

Theoretical Predictions

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.

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Imaging and diffraction modes in Scanning Transmission Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144814 ◽

1986 ◽

Vol 44 ◽

pp. 684-687

Author(s):

J. M. Cowley ◽

R. Glaisher ◽

J. A. Lin ◽

H.-J. Ou

Keyword(s):

Scanning Transmission Electron Microscopy ◽

High Efficiency ◽

Fiber Optic ◽

Image Intensifier ◽

Detector System ◽

Detector Plane ◽

Secondary Electrons ◽

Transmission Electron ◽

Scanning Transmission ◽

Special Detector

Some of the most important applications of STEM depend on the variety of imaging and diffraction made possible by the versatility of the detector system and the serial nature, of the image acquisition. A special detector system, previously described, has been added to our STEM instrument to allow us to take full advantage of this versatility. In this, the diffraction pattern in the detector plane may be formed on either of two phosphor screens, one with P47 (very fast) phosphor and the other with P20 (high efficiency) phosphor. The light from the phosphor is conveyed through a fiber-optic rod to an image intensifier and TV system and may be photographed, recorded on videotape, or stored digitally on a frame store. The P47 screen has a hole through it to allow electrons to enter a Gatan EELS spectrometer. Recently a modified SEM detector has been added so that high resolution (10Å) imaging with secondary electrons may be used in conjunction with other modes.

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Influence of MBE Growth Conditions on Dislocation Densities of GaAs/Ge Epilayers Grown on Silicon Substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118692 ◽

1985 ◽

Vol 43 ◽

pp. 364-365

Author(s):

K.M. Hones ◽

P. Sheldon ◽

B.G. Yacobi ◽

A. Mason

Keyword(s):

High Efficiency ◽

Lattice Mismatch ◽

Low Cost ◽

Growth Conditions ◽

Nonradiative Recombination ◽

Device Structure ◽

Si Substrates ◽

Transmission Electron ◽

Dislocation Densities ◽

Dislocation Type

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.

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The use of high-resolution FESEM to study solid-state phase transformations and reactions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172875 ◽

1994 ◽

Vol 52 ◽

pp. 1028-1029

Author(s):

P. G. Kotula ◽

D. D. Erickson ◽

C. B. Carter

Keyword(s):

Solid State ◽

High Resolution ◽

Phase Transformations ◽

High Efficiency ◽

Sol Gel ◽

Quantitative Information ◽

Solid State Reactions ◽

Critical Dimensions ◽

Backscattered Electrons ◽

Backscattered Electron

High-resolution field-emission-gun scanning electron microscopy (FESEM) has recently emerged as an extremely powerful method for characterizing the micro- or nanostructure of materials. The development of high efficiency backscattered-electron detectors has increased the resolution attainable with backscattered-electrons to almost that attainable with secondary-electrons. This increased resolution allows backscattered-electron imaging to be utilized to study materials once possible only by TEM. In addition to providing quantitative information, such as critical dimensions, SEM is more statistically representative. That is, the amount of material that can be sampled with SEM for a given measurement is many orders of magnitude greater than that with TEM.In the present work, a Hitachi S-900 FESEM (operating at 5kV) equipped with a high-resolution backscattered electron detector, has been used to study the α-Fe2O3 enhanced or seeded solid-state phase transformations of sol-gel alumina and solid-state reactions in the NiO/α-Al2O3 system. In both cases, a thin-film cross-section approach has been developed to facilitate the investigation. Specifically, the FESEM allows transformed- or reaction-layer thicknesses along interfaces that are millimeters in length to be measured with a resolution of better than 10nm.

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Interlayer confinement synthesis of Ir nanodots/dual carbon as an electrocatalyst for overall water splitting

Journal of Materials Chemistry A ◽

10.1039/d0ta09358k ◽

2020 ◽

Author(s):

Yaru Li ◽

Yu-Quan Zhu ◽

Weili Xin ◽

Song Hong ◽

Xiaoying Zhao ◽

...

Keyword(s):

Water Splitting ◽

Noble Metal ◽

High Efficiency ◽

Overall Water Splitting ◽

Highly Dispersed

Rationally designing low-content and high-efficiency noble metal nanodots offers opportunities to enhance electrocatalytic performances for water splitting. However, the preparation of highly dispersed nanodots electrocatalysts remains a challenge. Herein, we...

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