X‐ray measurement of an ultrasonic wave amplitude in a crystal

1975 ◽  
Vol 58 (2) ◽  
pp. 471-474 ◽  
Author(s):  
Kenneth Lazara ◽  
Jose M. Zayas ◽  
Alfred Zajac
Keyword(s):  
Ultrasonic Wave ◽  
Wave Amplitude ◽  
X Ray

scholarly journals Intra-Ring Wood Density and Dynamic Modulus of Elasticity Profiles for Black Spruce and Jack Pine from X-ray Densitometry and Ultrasonic Wave Velocity Measurement

Forests ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 569 ◽  
Author(s):  
Wassim Kharrat ◽  
Ahmed Koubaa ◽  
Mohamed Khlif ◽  
Chedly Bradai
Keyword(s):  
Ultrasonic Wave ◽  
Wave Velocity ◽  
Wood Density ◽  
Modulus Of Elasticity ◽  
Dynamic Modulus ◽  
Velocity Measurement ◽  
Black Spruce ◽  
Jack Pine ◽  
Ultrasonic Wave Velocity ◽  
X Ray

Currently, ultrasonic measurement is a widely used nondestructive approach to determine wood elastic properties, including the dynamic modulus of elasticity (DMOE). DMOE is determined based on wood density and ultrasonic wave velocity measurement. The use of wood average density to estimate DMOE introduces significant imprecision: Density varies due to intra-tree and intra-ring differences and differing silvicultural treatments. To ensure accurate DMOE assessment, we developed a prototype device to measure ultrasonic wave velocity with the same resolution as that provided by the X-ray densitometer for measuring wood density. A nondestructive method based on X-ray densitometry and the developed prototype was applied to determine radial and intra-ring wood DMOE profiles. This method provides accurate information on wood mechanical properties and their sources of variation. High-order polynomials were used to model intra-ring wood density and DMOE profiles in black spruce and jack pine wood. The transition from earlywood to latewood was defined as the inflection point. High and highly significant correlations were obtained between predicted and measured wood density and DMOE. An examination of the correlations between wood radial growth, density, and DMOE revealed close correlations between density and DMOE in rings, earlywood, and latewood

Effects of ultrasonic wave pretreatment on the fibrillation of cellulose fiber

TAPPI Journal ◽  
2014 ◽  
Vol 13 (4) ◽  
pp. 37-43 ◽  
Author(s):  
YONGJIAN XU ◽  
YING YAN ◽  
XIAOPENG YUE ◽  
ZHENFENG ZHU ◽  
DINGJUN ZHANG ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Bond Strength ◽  
Ftir Spectroscopy ◽  
Ultrasonic Wave ◽  
Internal Bond ◽  
Cellulose Fiber ◽  
Ultrasonic Waves ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
X Ray

Pinus massoniana Lamb. was used as the raw cellulose fiber material to investigate effects of ultrasonic wave pretreatment and PFI pretreatment on fiber bonding and absorbability. Influences of ultrasonic wave pretreatment on fiber crystalline structure and hydrogen bonds were also analyzed by wide-angle X-ray diffraction and Fourier transform infrared (FTIR) spectroscopy. The absorption and internal bond strength of fiber pretreated by ultrasonic waves increased by 23.49% and 4.07%, respectively, in comparison with those of virgin fiber, which would result in the improvement of weak bonding and absorbability. Instead, when fiber was pretreated by PFI, absorption decreased in comparison with virgin fiber and internal bond strength increased as much as 1.33 times than that of virgin fiber. The analysis of wide-angle X-ray diffraction curves and FTIR spectroscopy curves revealed that the crystallinity of fiber decreased by 20.59% in comparison with that of virgin fiber when treated by ultrasonic waves. Moreover, the effect of ultrasonic wave pretreatment on intramolecular hydrogen bonds was rather stronger than that of intermolecular hydrogen bonds. Therefore, the optimal swelling ability of fiber would be obtained.

Preparation of Micro-Sized Silver Powder Utilized in Paste for Solar Cell Grid Electrode

2011 ◽  
Vol 412 ◽  
pp. 247-250
Author(s):  
Ya Zheng ◽  
Guo You Gan ◽  
Lei Zhang ◽  
Ji Kang Yan ◽  
Jing Hong Du ◽  
...  
Keyword(s):  
Solar Cell ◽  
Ultrasonic Wave ◽  
Chemical Reduction ◽  
Silver Powder ◽  
Narrow Particle Size Distribution ◽  
Protective Mechanism ◽  
Silver Particles ◽  
X Ray Diffraction ◽  
Grid Electrode ◽  
X Ray

The micro-sized silver used for solar cell grid electrode was obtained from silver nitrate via chemical reduction under ultrasonic wave and alkaline environment using polyethylene glycol (PEG-6000) as dispersant and alcohol as surfactant, and after agitation, the sol was filtered, washed and dried at constant temperature. The PEG and alcohol protective mechanism in the preparing process of spherical silver particles was studied. Effects of the amount of dispersant, pH, dosage of alcohol, were investigated. The silver powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Results show that with 0.35mol/LAgNO3 solution, 25mL ethanol, T = 40°C, pH = 8 and 10min ultrasonic wave, spherical silver power about 1.38 ~ 2.11μm with narrow particle size distribution was fabricated. The paste prepared with ready-made silver powder was printed on the silicon and the contact resistance is very low, indicating the electrical property of the prepared silver is qualified for solar cells.

scholarly journals Experimental Investigation on the Deformability, Ultrasonic Wave Propagation, and Acoustic Emission of Rock Salt Under Triaxial Compression

2019 ◽  
Vol 9 (4) ◽  
pp. 635 ◽  
Author(s):  
Haoran Li ◽  
Zhikai Dong ◽  
Zuolin Ouyang ◽  
Bo Liu ◽  
Wei Yuan ◽  
...  
Keyword(s):  
Crack Initiation ◽  
Ultrasonic Wave ◽  
Attenuation Coefficient ◽  
Rock Salt ◽  
Wave Amplitude ◽  
Ultrasonic Waves ◽  
Ultimate Stress ◽  
Rock Damage ◽  
Brittle Ductile Transition ◽  
Experimental Apparatus

Ultrasonic waves, which constitute an active testing method, and acoustic emissions (AE), which can be applied as passive testing technology, can reveal rock damage processes in different ways. However, few studies so far have simultaneously adopted both, owing to the limitations of the experimental apparatus. However, the simultaneous use of both methods can improve the experimental efficiency and help to understand the rock damage evolution more comprehensively. In this study, concurrent experiments of ultrasonic waves and AE activities were carried out on rock salt under uniaxial compression, and the deformation characteristics were measured. The fracture process was divided into four stages with individual characteristics: the elastic compression stage, brittle-ductile transition with crack initiation, brittle-ductile transition with damage initiation, and plastic deformation and strain hardening stage. The ultrasonic wave velocity, crack density, ultrasonic wave amplitude, and attenuation coefficient were obtained to evaluate the damage process. The ultrasonic wave amplitude and the attenuation coefficient were recommended as forecast indicators, owing to their sensitivity and operability of measurement. The confining pressure had an inhibitory effect on crack expansion and on the AE activity, and the damage ultimate stress was defined and determined according to the AE activity and energy release characteristics. Four critical strengths of the crack initiation threshold stress, dilatancy boundary stress, short-term strength, and damage ultimate stress of rock salt were determined and then discussed. These results are valuable in evaluating rock damage and guiding the operation of underground salt caverns.

Oil Debris Detection Using Capacitance and Ultrasonic Measurements

2007 ◽  
Author(s):  
J. Zhe ◽  
F. K. Choy ◽  
S. V. Murali ◽  
M. A. Sarangi ◽  
R. Wilfong
Keyword(s):  
Particle Size ◽  
Ultrasonic Wave ◽  
Wave Amplitude ◽  
Systematic Difference ◽  
Ultrasonic Measurement ◽  
Experimental Results ◽  
Capacitance Measurements ◽  
Ultrasonic Device ◽  
Ultrasonic Measurements ◽  
Oil Debris

This paper aims at the use of a capacitance sensing approach using a RLC meter to detect oil debris contents and experimental results are compared to those obtained using an ultrasonic device. It was found that both capacitance and ultrasonic measurement can both detect particles as small as 4 mils (101 μm) in diameter. Experimental results show that the measured capacitance increases linearly with the increase of particle size while the ultrasonic wave amplitude decreases linearly with the increase of particle size. While some measurable differences can be detected by both capacitance and ultrasonic measurements between the ferrous and the nonferrous particles, a systematic difference between the data point cannot be developed. In addition, the existence of nonconductive particles cannot be readily detected using the capacitance measurements but their existence can be observed by the ultrasonic measurement.

scholarly journals Synthesis and Characteristics of Multifunctional Magneto-luminescent Nanoparticles by an Ultrasonic Wave-assisted Stӧber Method

2021 ◽  
Vol 32 (3) ◽  
pp. 75-87
Author(s):  
Tien Dung Chu ◽  
◽  
Hoang Nam Nguyen ◽  
◽  
◽  
...  
Keyword(s):  
Ultrasonic Wave ◽  
Biomedical Applications ◽  
X Ray Diffraction ◽  
Sio2 Matrix ◽  
Stöber Method ◽  
Raman Scattering Spectroscopy ◽  
X Ray ◽  
Saturation Magnetisation ◽  
Transmission Electron ◽  
Luminescent Nanoparticles

Multifunctional magneto-luminescent nanoparticles (NPs) were synthesised by an ultrasonic wave-assisted Stöber method. The multifunctional NPs are composed of magnetic NPs (Fe3O4) and photoluminescent quantum dots (QDs) (ZnS:Mn) in amorphous silica (SiO2) matrix, which was confirmed by X-ray diffraction, Raman scattering spectroscopy, and transmission electron microscopy (TEM). The multifunctional NPs have high saturation magnetisation at room temperature simultaneously with strong photoluminescence (PL) in visible light, which is promising for biomedical applications.

Intrinsic corporoantropyloric coordination of motility and gastric emptying

1994 ◽  
Vol 266 (2) ◽  
pp. G255-G262 ◽  
Author(s):  
G. E. Holle ◽  
E. Steinbach ◽  
W. Forth
Keyword(s):  
Gastric Emptying ◽  
Slow Wave ◽  
Gastric Motility ◽  
Wave Amplitude ◽  
Proximal Part ◽  
Platinum Electrodes ◽  
Motility Index ◽  
X Ray ◽  
Force Transducers ◽  
Meat Meal

This study examined changes in gastric motility after interruption of the intramural nervous circuitry from the proximal portion of the stomach to the antrum by a circumferential gastric myotomy. Seven extraluminal strain gauge force transducers and five platinum electrodes were implanted along the antropyloroduodenal region, and gastric emptying was studied by X-ray after a 280-g solid meat meal mixed with barium. The motility index increased aboral to the myotomy by 106 and 69% in the distal antrum and pylorus, respectively, in the first postprandial 30-60 min because of the loss of an inhibitory neural influence from the proximal part of the stomach. Destabilization of the basic electrical rhythm occurred in 50% of the dogs. This was apparent as tachyarrhythmia or bradyarrhythmia and an early postprandial 2-11% decrease in slow-wave frequency and a 100% increase in slow-wave amplitude. Coordination of corporoantropyloric contractions was disorganized. Frequent segmenting and antidromic contractions were associated with reduced periods of optimal emptying and disturbed intragastric chyme transport into the constricted antrum. A 10-30% gastric emptying delay of approximately 50 min was a consequence of myotomy despite an increased antroduodenal motor gradient after myotomy. The overall results suggest that intact intramural innervation and muscular continuity are essential for coordination of corporoantropyloric motility and normal gastric emptying.

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