Ultrasonic sensor signals and optimum path forest classifier for the microstructural characterization of thermally-aged inconel 625 alloy.

Science.gov (United States)

de Albuquerque, Victor Hugo C; Barbosa, Cleisson V; Silva, Cleiton C; Moura, Elineudo P; Filho, Pedro P Rebouças; Papa, João P; Tavares, João Manuel R S

2015-05-27

Secondary phases, such as laves and carbides, are formed during the final solidification stages of nickel-based superalloy coatings deposited during the gas tungsten arc welding cold wire process. However, when aged at high temperatures, other phases can precipitate in the microstructure, like the γ'' and δ phases. This work presents an evaluation of the powerful optimum path forest (OPF) classifier configured with six distance functions to classify background echo and backscattered ultrasonic signals from samples of the inconel 625 superalloy thermally aged at 650 and 950 °C for 10, 100 and 200 h. The background echo and backscattered ultrasonic signals were acquired using transducers with frequencies of 4 and 5 MHz. The potentiality of ultrasonic sensor signals combined with the OPF to characterize the microstructures of an inconel 625 thermally aged and in the as-welded condition were confirmed by the results. The experimental results revealed that the OPF classifier is sufficiently fast (classification total time of 0.316 ms) and accurate (accuracy of 88.75%" and harmonic mean of 89.52) for the application proposed.

De novo transcriptome profiling of cold-stressed siliques during pod filling stages of Indian mustard (Brassica juncea L.

Directory of Open Access Journals (Sweden)

Somya eSinha

2015-10-01

Full Text Available Low temperature is a major abiotic stress that impedes plant growth and development. Brassica juncea is an economically important oil seed crop and is sensitive to freezing stress during pod filling subsequently leading to abortion of seeds. To understand the cold stress mediated global perturbations in gene expression, whole transcriptome of B. juncea siliques that were exposed to sub-optimal temperature was sequenced. Manually self-pollinated siliques at different stages of development were subjected to either short (6 h or long (12 h durations of chilling stress followed by construction of RNA-seq libraries and deep sequencing using Illumina’s NGS platform. De-novo assembly of B. juncea transcriptome resulted in 133641 transcripts, whose combined length was 117 Mb and N50 value was 1428 bp. We identified 13342 differentially regulated transcripts by pair-wise comparison of 18 transcriptome libraries. Hierarchical clustering of these differentially expressed transcripts along with Spearman correlation analysis identified two major clusters representing early (5-15 DAP and late stages (20-30 DAP of silique development. Detailed analysis led to the discovery of two gene expression clusters whose transcripts were inducible at both durations of the cold stress irrespective of the developmental stages. We further explored the expression patterns of gene families encoding for transcription factors (TFs, transcription regulators (TRs and kinases, and found that cold stress induced protein kinases specifically during early silique development. We validated the digital gene expression profiles of selected transcripts by qPCR and found a high degree of concordance between the two analyses. To our knowledge this is the first report of transcriptome sequencing of cold-stressed B. juncea siliques. The data generated in this study would be a valuable resource for not only understanding the cold stress signaling pathway but also for introducing cold

Characterization of microstructures in austenitic stainless steels by ultrasonics

International Nuclear Information System (INIS)

Raj, Baldev; Palanichamy, P.; Jayakumar, T.; Kumar, Anish; Vasudevan, M.; Shankar, P.

2000-01-01

Recently, many nondestructive techniques have been considered for microstructural characterization of materials to enable in-situ component assessment for pre-service quality and in-service performance. Ultrasonic parameters have been used for estimation of average grain size, evaluation of recrystallization after cold working, and characterization of Cr2N precipitation during thermal aging in different grades of austenitic stainless steels. Ultrasonic first back wall echo signals were obtained from several specimens of AISI type 316 stainless steel with different grain sizes. Shift in the spectral peak frequency and the change in the full width at half maximum of the autopower spectrum of the first back wall echo are correlated with the grain size in the range 30-150 microns. The advantages of this method are: (i) independence of variation in couplant conditions (ii), applicable even to highly attenuating materials, (iii) direct correlation of the ultrasonic parameters with yield strength and (iv) suitability for shop-floor applications. Recrystallization behavior (temperature range 973-1173 K and time durations 0.5-1000 h) of cold worked titanium modified 316 stainless steel (D9) has been characterized using ultrasonic velocity measurements. A velocity parameter derived using a combination of shear and longitudinal wave velocities is correlated with the degree of recrystallization. These velocity measurement could also identify onset, progress and completion of recrystallization more accurately as compared to hardness and strength measurements. Ultrasonic velocity measurements were performed in thermally aged (at 1123 K for 10 to 2000 h) nuclear grade 316 LN stainless steel. Change in velocity due to thermal aging treatment could be used to reveal the formation of (i) Cr-N clusters associated with high lattice strains, (ii) coherent Cr2N precipitation, (iii) loss of coherency and (iv) growth of incoherent Cr2N precipitates. Microstructural characterization by

Mapping and validation of QTLs for cold tolerance at seedling stage in rice from an indica cultivar Habiganj Boro VI (Hbj.BVI).

Science.gov (United States)

Biswas, Partha S; Khatun, Hasina; Das, Nomita; Sarker, Md Mahathir; Anisuzzaman, M

2017-12-01

Yellowing, stunting, and seedling death associated with cold stress is a common problem in many Asian countries for winter rice cultivation. Improvement of cultivars through marker-assisted selection of QTLs for cold tolerance at seedling stage from locally adapted germplasm/cultivar is the most effective and sustainable strategy to resolve this problem. A study was undertaken to map QTLs from 151 F 2:3 progenies of a cross between a cold susceptible variety, BR1 and a locally adapted traditional indica cultivar, Hbj.BVI. A total of six significant QTLs were identified for two cold tolerance indices-cold-induced leaf discoloration and survival rate after a recovery period of seven days on chromosomes 6, 8, 11, and 12. Among these QTLs, qCTSL - 8 - 1 and qCTSS - 8 - 1 being co-localized into RM7027-RM339 on chromosome 8 and qCTSL - 12 - 1 and qCTSS - 12 - 1 into RM247-RM2529 on chromosome 12 showed 12.78 and 14.96% contribution, respectively, to the total phenotypic variation for cold tolerance. Validation of QTL effect in BC 1 F 3 population derived a cross between a cold susceptible BRRI dhan28 and Hbj.BVI showed dominating effect of qCTSL - 12 - 1 on cold tolerance at seedling stage and it became stronger when one or more other QTLs were co-segregated with it. These results suggest that the QTLs identified in this study are stable and effective on other genetic background also, which warrant the use of these QTLs for further study aiming to cultivar development for seedling stage cold tolerance.

Ultrasonic guided wave for monitoring corrosion of steel bar

Science.gov (United States)

Liu, Xi; Qin, Lei; Huang, Bosheng

2018-01-01

Steel corrosion of reinforced concrete structures has become a serious problem all over the word. In this paper, the work aims at monitoring steel corrosion using ultrasonic guided wave (UGW). Ultrasonic guided wave monitoring is a dynamic and non-destructive testing technology. The advantages of ultrasonic guided wave monitoring for reinforcement corrosion are real-time, online and continuous. In addition, it can judge the different stages of steel bar corrosion, which achieved non-destructive detection.

Ultrasonication aided in-situ transesterification of microbial lipids to biodiesel.

Science.gov (United States)

Zhang, Xiaolei; Yan, Song; Tyagi, Rajeshwar Dayal; Surampalli, Rao Y; Valéro, Jose R

2014-10-01

In-situ transesterification of microbial lipid to biodiesel has been paid substantial attention due to the fact that the lipid extraction and transesterification can be conducted in one-stage process. To improve the feasibility of in-situ transesterification, ultrasonication was employed to reduce methanol requirement and reaction time. The results showed that the use of ultrasonication could achieve high conversion of lipid to FAMEs (92.1% w lipid conversion/w total lipids) with methanol to lipid molar ratio 60:1 and NaOH addition 1% w/w lipid in 20 min, while methanol to lipid molar ratio 360:1, NaOH addition 1% w/w lipid, and reaction time 12h was required to obtain similar yield in in-situ transesterification without ultrasonication. The compositions of FAMEs obtained in case of ultrasonication aided in-situ transesterification were similar as that of two-stage extraction followed by transesterification processes. Copyright © 2014. Published by Elsevier Ltd.

The Effects of Cold Stress at Germination and Seedling Stages on Antioxidant Enzymes and Some Physiological Aspects of Chickpea (Cicer arientinum.

Directory of Open Access Journals (Sweden)

S. Wanaei

2012-04-01

Full Text Available In order to investigate the effects of cold stress on antioxidant enzymes and physiological characteristics in chickpea, two separate experiments were conducted at germination and seedling stages. Each experiment with six temperature levels (T1(control=15C°, T2=5C°, T3=0C°, T4=-5C°, T5=-10C° and T6=-15C° and three varieties (V1=Pirouz V2=ILC482 V3=Bivaniej was carried out in a randomized complete block design with three replications at controlled condition in crop physiological laboratory of Kurdistan university at 2009. The results showed that cold treatment increased Catalase and Peroxdase activity, cell membrane injury and H2O2 concentration significantly. The temperature -5C° treatment had the most influence on physiological traits. Based on germination stage trial, ILC482 was known as resistance cultivar and Pirouz showed highest sensitivity to cold treatments. There were positive and significant correlation between H2O2 concentration with Catalase (r = 0.98** and Peroxidase (r = 0.89** at germination stage. Peroxidase activity was about tenfold more of the Catalase activity. In general, the results showed that cold stress increased reactive oxygen species; these product lead to oxidative damages to cell membrane.

Ultrasonic processing for recovery of chicken erythrocyte hemoglobin

Science.gov (United States)

Hemoglobin from chicken blood has been shown to be a good substitute for synthetic polymeric flocculants. One stage of processing the blood entails breaking open the cells and releasing the cytoplasmic contents; in the present study, we investigate the use of ultrasonic processing at this stage. Was...

Ultrasonic Testing

Energy Technology Data Exchange (ETDEWEB)

Lee, Hyeong Jun; Kuk, Jeong Han

2002-02-15

This book introduces ultrasonic testing, which tells of outline of ultrasonic testing, principle of ultrasonic testing, prosperities of ultrasonic waves, radiographic test and ultrasonic test, basic theory on ultrasonic testing, mode conversion, transmission and diffraction, ultrasonic flaw detection and probe, standard test piece and reference test piece, like KS(JIS) ASME and ASTM, classification and properties of ultrasonic testing, straight beam method, angle beam method, ASME SEC.V.Art.5 ASTMA 388 and KS B 0817 Korean industrial standard.

Investigation of multi-stage cold forward extrusion process using coupled thermo-mechanical finite element analysis

Science.gov (United States)

Görtan, Mehmet Okan

2018-05-01

Cold extrusion processes are distinguished by their low material usage as well as great efficiency in the production of mid-range and large component series. Although majority of the cold extruded parts are produced using die systems containing multiple forming stages, this subject has rarely been investigated so far. Therefore, the characteristics of multi-stage cold forward rod extrusion is studied in the current work using thermo-mechanically coupled finite element (FE) analysis. A case hardening steel, 16MnCr5 (1.7131) was used as experimental material. Its strain, strain rate and temperature dependent mechanical characteristics were determined using compression testing and modeled in FE simulations via a Johnson-Cook material model. Friction coefficients for the same material while in contact with a tool steel (1.2379) were determined dependent on temperature and contact pressure using sliding compression test (SCT) and modeled by an adaptive friction model developed by the author. In the first set of simulations, rod material with a diameter of 14.9 mm was extruded down to a diameter of 9.6 mm in a single step using three different die opening angles (2α); 20°, 40° and 60°. In the second set of investigations, the same rod was reduced first to 12 mm and then to 9.6 mm in two steps within the same forming die. Press forces, contact normal stresses between extruded material and forming die, material temperature and axial stresses are compared in these two set of simulations and the differences are discussed.

[Effects of ultrasonic pretreatment on drying characteristics of sewage sludge].

Science.gov (United States)

Li, Run-Dong; Yang, Yu-Ting; Li, Yan-Long; Niu, Hui-Chang; Wei, Li-Hong; Sun, Yang; Ke, Xin

2009-11-01

The high water content of sewage sludge has engendered many inconveniences to its treatment and disposal. While ultrasonic takes on unique advantages on the sludge drying because of its high ultrasonic power, mighty penetrating capability and the ability of causing cavitations. Thus this research studies the characteristics influences of ultrasonic bring to the sludge drying and effects of the exposure time, ultrasonic generator power, temperatures of ultrasonic and drying temperature on the drying characteristics of dewatered sludge. Results indicate that ultrasonic pretreatment could speed up evaporation of the free water in sludge surface and help to end the drying stage with constant speed. In addition, ultrasonic treatment can effectively improve the sludge drying efficiency which could be more evident with the rise of the ultrasonic power (100-250 W), ultrasonic temperature and drying temperature. If dried under low temperature such as 105 degrees C, sludge will have premium drying characteristics when radiated under ultrasound for a shorter time such as 3 min. In the end, the ultrasonic treatment is expected to be an effective way to the low-cost sludge drying and also be an important reference to the optimization of the sludge drying process because of its effects on the increase of sludge drying efficiency.

Ultrasonic imaging of projected components of PFBR

Energy Technology Data Exchange (ETDEWEB)

Sylvia, J.I., E-mail: sylvia@igcar.gov.in [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India); Jeyan, M.R.; Anbucheliyan, M.; Asokane, C.; Babu, V. Rajan; Babu, B.; Rajan, K.K.; Velusamy, K.; Jayakumar, T. [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India)

2013-05-15

Highlights: ► Under sodium ultrasonic scanner in PFBR is for detecting protruding objects. ► Feasibility study for detecting Absorber rods and its drive mechanisms. ► Developed in-house PC based ultrasonic imaging system. ► Different case studies were carried out on simulated ARDM's. ► Implemented the experimental results to PFBR application. -- Abstract: The 500 MWe, sodium cooled, Prototype Fast Breeder Reactor (PFBR) is under advanced stage of construction at Kalpakkam in India. Opacity of sodium restricts visual inspection of components immersed in sodium by optical means. Ultrasonic wave passes through sodium hence ultrasonic techniques using under sodium ultrasonic scanners are developed to obtain under sodium images. The main objective of such an Under Sodium Ultrasonic Scanner (USUSS) for Prototype Fast Breeder Reactor (PFBR) is to detect and ensure that no core Sub Assembly (SA) or Absorber Rod or its Drive Mechanism is protruded in the above core plenum before starting the fuel handling operation. Hence, it is necessary to detect and locate the object, if it is protruding the above core plenum. To study the feasibility of detecting the absorber rods and their drive mechanisms using direct ultrasonic imaging technique, experiments were carried out for different orientations and profiles of the projected components in a 5 m diameter water tank. The in-house developed PC based ultrasonic scanning system is used for acquisition and analysis of data. The pseudo three dimensional color images obtained are discussed and the results are applicable for PFBR. This paper gives the details of the features of the absorber rods and their drive mechanisms, their orientation in the reactor core, experimental setup, PC based ultrasonic scanning system, ultrasonic images and the discussion on the results.

Dental hard tissue characterization using laser-based ultrasonics

Science.gov (United States)

Blodgett, David W.; Massey, Ward L.

2003-07-01

Dental health care and research workers require a means of imaging the structures within teeth in vivo. One critical need is the detection of tooth decay in its early stages. If decay can be detected early enough, the process can be monitored and interventional procedures, such as fluoride washes and controlled diet, can be initiated to help re-mineralize the tooth. Currently employed x-ray imaging is limited in its ability to visualize interfaces and incapable of detecting decay at a stage early enough to avoid invasive cavity preparation followed by a restoration. To this end, non-destructive and non-contact in vitro measurements on extracted human molars using laser-based ultrasonics are presented. Broadband ultrasonic waves are excited in the extracted sections by using a pulsed carbon-dioxide (CO2) laser operating in a region of high optical absorption in the dental hard tissues. Optical interferometric detection of the ultrasonic wave surface displacements in accomplished with a path-stabilized Michelson-type interferometer. Results for bulk and surface in-vitro characterization of caries are presented on extracted molars with pre-existing caries.

High-power ultrasonic processing: Recent developments and prospective advances

Science.gov (United States)

Gallego-Juarez, Juan A.

2010-01-01

Although the application of ultrasonic energy to produce or to enhance a wide variety of processes have been explored since about the middle of the 20th century, only a reduced number of ultrasonic processes have been established at industrial level. However, during the last ten years the interest in ultrasonic processing has revived particularly in industrial sectors where the ultrasonic technology may represent a clean and efficient tool to improve classical existing processes or an innovation alternative for the development of new processes. Such seems to be the case of relevant sectors such as food industry, environment, pharmaceuticals and chemicals manufacture, machinery, mining, etc where power ultrasound is becoming an emerging technology for process development. The possible major problem in the application of high-intensity ultrasound on industrial processing is the design and development of efficient power ultrasonic systems (generators and reactors) capable of large scale successful operation specifically adapted to each individual process. In the area of ultrasonic processing in fluid media and more specifically in gases, the development of the steppedplate transducers and other power ge with extensive radiating surface has strongly contributed to the implementation at semi-industrial and industrial stage of several commercial applications, in sectors such as food and beverage industry (defoaming, drying, extraction, etc), environment (air cleaning, sludge filtration, etc...), machinery and process for manufacturing (textile washing, paint manufacture, etc). The development of different cavitational reactors for liquid treatment in continuous flow is helping to introduce into industry the wide potential of the area of sonochemistry. Processes such as water and effluent treatment, crystallization, soil remediation, etc have been already implemented at semi-industrial and/or industrial stage. Other single advances in sectors like mining or energy have

Detecting accuracy of flaws by manual and automatic ultrasonic inspections

International Nuclear Information System (INIS)

Iida, K.

1988-01-01

As the final stage work in the nine year project on proving tests of the ultrasonic inspection technique applied to the ISI of LWR plants, automatic ultrasonic inspection tests were carried out on EDM notches, surface fatigue cracks, weld defects and stress corrosion cracks, which were deliberately introduced in full size structural components simulating a 1,100 MWe BWR. Investigated items are the performance of a newly assembled automatic inspection apparatus, detection limit of flaws, detection resolution of adjacent collinear or parallel EDM notches, detection reproducibility and detection accuracy. The manual ultrasonic inspection of the same flaws as inspected by the automatic ultrasonic inspection was also carried out in order to have comparative data. This paper reports how it was confirmed that the automatic ultrasonic inspection is much superior to the manual inspection in the flaw detection rate and in the detection reproducibility

Effect of ultrasonic cold forging technology as the pretreatment on the corrosion resistance of MAO Ca/P coating on AZ31B Mg alloy

Energy Technology Data Exchange (ETDEWEB)

Chen, Lingling, E-mail: daisy_chenlingling@163.com [College of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617 (China); College of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Gu, Yanhong, E-mail: gu_yanhong@163.com [College of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617 (China); Liu, Lu, E-mail: liulu@bipt.edu.cn [College of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617 (China); Liu, Shujing, E-mail: liushujing@bipt.edu.cn [College of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617 (China); Hou, Binbin, E-mail: sohu19880815@126.com [School of Engineering and Technology, China University of Geosciences, Beijing 100083 (China); Liu, Qi, E-mail: 13521196884@sina.cn [College of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617 (China); Ding, Haiyang, E-mail: dinghaiyang@bipt.edu.cn [College of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617 (China)

2015-06-25

Highlights: • Ultrasonic cold forging technology was used as the pretreatment for MAO coating. • Nano layer with the grain size of 30–80 nm was formed on the UCFT treated surface. • Calcium phosphate contained coating was obtained by MAO process. • The remained nano layer underlying MAO coating could impact the corrosion resistance greatly. - Abstract: A calcium phosphate contained (Ca/P) coating was obtained on AZ31B Mg alloy by micro-arc oxidation (MAO) process under the pretreatment of ultrasonic cold forging technology (UCFT). The surface nanograins were introduced after UCFT pretreatment on AZ31B Mg alloy. Optical microscope (OM) was employed to observe the microstructures of the untreated and UCFT treated samples. Transmission electron microscopy (TEM) and atomic force microscope (AFM) were employed to observe the microstructures of nanograins and the surface roughness of the UCFT treated Mg alloys. The grain size of the UCFT treated Mg alloy is 48.67 nm and the surface roughness is 17.03 nm. The microstructures and the phase compositions of MAO samples were observed and analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The XRD results show that the coating include Ca/P phase, including hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}), HA), tertiary calcium phosphate (Ca{sub 3}(PO{sub 4}){sub 2}, TCP) and calcium phosphate dehydrate (CaHPO{sub 4}⋅2H{sub 2}O, DCPD). The hardness of the samples was measured by the micro-hardness tester under the loads of 10 g, 25 g and 50 g. 3D topographies of hardness indenter were characterized by 3D profiler. The immersion tests and potentiodynamic polarization tests were used to evaluate the weight loss rate and corrosion current density in simulated body fluid (SBF). The results show that the corrosion resistance of Ca/P MAO coating on Mg alloy was improved greatly by the pretreatment of UCFT.

Energy-Based Analysis of Ultrasonically Assisted Turning

Directory of Open Access Journals (Sweden)

G.A. Volkov

2011-01-01

Full Text Available The process of ultrasonically-assisted turning (UAT is a superposition of vibration of a cutting tool on its standard movement in conventional turning (CT. The former technique has several advantages compared with the latter, one of the main being a significant decrease in the level of cutting forces. In this paper the effects observed in UAT are analysed employing ideas of dynamic fracture mechanics. The active stage of loading duration depends heavily on ultrasonic frequency and the cutting speed; he application of the fracture criterion based on the notion of incubation time makes it possible to calculate a dependence of this duration on its threshold amplitude. An estimation of energy, necessary to create a threshold pulse in the material, is made by solving the contact Hertz problem. The obtained time dependence of energy has a marked minimum. Thus, the existence of energy-efficient loading duration is demonstrated. This explains the decrease in the cutting force resulting from superimposed ultrasonic vibration. The obtained results are in agreement with experiments on ultrasonic assisted machining of aluminium and Inconel 718 alloy.

Mechanochemical degradation of potato starch paste under ultrasonic irradiation

Institute of Scientific and Technical Information of China (English)

LI Jian-bin; LI Lin; LI Bing; CHEN Ling; GUI Lin

2006-01-01

In the paper, changes in the molecular weight, the intrinsic viscosity and the polydispersity (molecular mass distribution) of treated potato starch paste were studied under different ultrasonic conditions which include irradiation time, ultrasonic intensity, potato starch paste concentration, and distance from probe tip on the degradation of potato starch paste. Intrinsic viscosity of potato starch paste was determined following the ASTM (American Society for Testing and Materials) standard practice for dilute solution viscosity of polymers. Molecular mass and polydispersity of potato starch paste were measured on GPC (Gel Permeation Chromatography). The results showed that the average molecular mass and the intrinsic viscosity of starch strongly depended on irradiation time. Degradation increased with prolonged ultrasonic irradiation time, and the increase of ultrasonic intensity could accelerate the degradation, resulting in a faster degradation rate, a lower limiting value and a higher degradation extent. Starch samples were degraded faster in dilute solutions than in concentrated solutions. The molecular mass and the intrinsic viscosity of starch increased with the increase of distance from probe tip. Our results also showed that the polydispersity decreased with ultrasonic irradiation under all ultrasonic conditions. Ultrasonic degradation of potato starch paste occured based on the mechanism of molecular relaxation of starch paste. In the initial stage, ultrasonic degradation of potato starch paste was a random process, and the molecular mass distribution was broad. After that, ultrasonic degradation of potato starch paste changed to a nonrandom process, and the molecular mass distribution became narrower. Finally, molecular mass distribution tended toward a saturation value.

Design and cold-air test of single-stage uncooled turbine with high work output

Science.gov (United States)

Moffitt, T. P.; Szanca, E. M.; Whitney, W. J.; Behning, F. P.

1980-01-01

A solid version of a 50.8 cm single stage core turbine designed for high temperature was tested in cold air over a range of speed and pressure ratio. Design equivalent specific work was 76.84 J/g at an engine turbine tip speed of 579.1 m/sec. At design speed and pressure ratio, the total efficiency of the turbine was 88.6 percent, which is 0.6 point lower than the design value of 89.2 percent. The corresponding mass flow was 4.0 percent greater than design.

Ultrasonic testing

Energy Technology Data Exchange (ETDEWEB)

Song, Sung Jin [Sungkwunkwan Univ., Seoul (Korea, Republic of); Jeong, Hyun Jo [Wonkwang Univ., Iksan (Korea, Republic of)

2004-02-15

For the proper performance of ultrasonic testing of steel welded joints, and anisotropic material it is necessary to have sound understanding on the underlying physics. To provide such an understanding, it is beneficial to have simulation tools for ultrasonic testing. In order to address such a need, we develop effective approaches to simulate angle beam ultrasonic testing with a personal computer. The simulation is performed using ultrasonic measurement models based on the computationally efficient multi-Gaussian beams. This reach will describe the developed ultrasonic testing models together with the experimental verification of their accuracy.

Autolysis of Pichia pastoris induced by cold.

Science.gov (United States)

Bartolo-Aguilar, Yaneth; Dendooven, Luc; Chávez-Cabrera, Cipriano; Flores-Cotera, Luis B; Hidalgo-Lara, María E; Villa-Tanaca, Lourdes; Marsch, Rodolfo

2017-12-01

The production of recombinant biopharmaceutical proteins is a multi-billion dollar market. Protein recovery represents a major part of the production costs. Pichia pastoris is one of the microbial systems most used for the production of heterologous proteins. The use of a cold-induced promoter to express lytic enzymes in the yeast after the growth stage could reduce protein recovery costs. This study shows that a cold-shock can be applied to induce lysis of the yeast cells. A strain of P. pastoris was constructed in which the endogenous eng gene encoding a putative endo-β-1,3-glucanase was overexpressed using the cold-shock induced promoter of the cctα gene from Saccharomyces cerevisiae. In the transgenic P. pastoris, the expression of eng increased 3.6-fold after chilling the cells from 30 to 4 °C (cold-shock stage) followed by incubation for 6 h (eng expression stage). The culture was heated to 30 °C for 6 h (ENG synthesis stage) and kept at 37 °C for 24 h (lysis stage). After this procedure the cell morphology changed, spheroplasts were obtained and cellular lysis was observed. Thus, a clone of P. pastoris was obtained, which undergoes autolysis after a cold-shock.

Strengthening power generation efficiency utilizing liquefied natural gas cold energy by a novel two-stage condensation Rankine cycle (TCRC) system

International Nuclear Information System (INIS)

Bao, Junjiang; Lin, Yan; Zhang, Ruixiang; Zhang, Ning; He, Gaohong

2017-01-01

Highlights: • A two-stage condensation Rankine cycle (TCRC) system is proposed. • Net power output and thermal efficiency increases by 45.27% and 42.91%. • The effects of the condensation temperatures are analyzed. • 14 working fluids (such as propane, butane etc.) are compared. - Abstract: For the low efficiency of the traditional power generation system with liquefied natural gas (LNG) cold energy utilization, by improving the heat transfer characteristic between the working fluid and LNG, this paper has proposed a two-stage condensation Rankine cycle (TCRC) system. Using propane as working fluid, compared with the combined cycle in the conventional LNG cold energy power generation method, the net power output, thermal efficiency and exergy efficiency of the TCRC system are respectively increased by 45.27%, 42.91% and 52.31%. Meanwhile, the effects of the first-stage and second-stage condensation temperature and LNG vaporization pressure on the performance and cost index of the TCRC system (net power output, thermal efficiency, exergy efficiency and UA) are analyzed. Finally, using the net power output as the objective function, with 14 organic fluids (such as propane, butane etc.) as working fluids, the first-stage and second-stage condensation temperature at different LNG vaporization pressures are optimized. The results show that there exists a first-stage and second-stage condensation temperature making the performance of the TCRC system optimal. When LNG vaporization pressure is supercritical pressure, R116 has the best economy among all the investigated working fluids, and while R150 and R23 are better when the vaporization pressure of LNG is subcritical.

Reactor Coolant Temperature Measurement using Ultrasonic Technology

Energy Technology Data Exchange (ETDEWEB)

Jung, JaeCheon [KEPCO International Nuclear graduate School, Ulsan (Korea, Republic of); Seo, YongSun; Bechue, Nicholas [Krohne Messtechnik GmbH, Duisburg (Germany)

2016-10-15

In NPP, the primary piping temperature is detected by four redundant RTDs (Resistance Temperature Detectors) installed 90 degrees apart on the RCS (Reactor Coolant System) piping circumferentially. Such outputs however, if applied to I and C systems would not give balanced results. The discrepancy can be explained by either thermal stratification or improper arrangement of thermo-wells and RTDs. This phenomenon has become more pronounced in the hot-leg piping than in the cold-leg. Normally, the temperature difference among channels is in the range of 1°F in Korean nuclear power Plants. Consequently, a more accurate pipe average temperate measurement technique is required. Ultrasonic methods can be used to measure average temperatures with relatively higher accuracy than RTDs because the sound wave propagation in the RCS pipe is proportional to the average temperature around pipe area. The inaccuracy of RCS temperature measurement worsens the safety margin for both DNBR and LPD. The possibility of this discrepancy has been reported with thermal stratification effect. Proposed RCS temperature measurement system based on ultrasonic technology offers a countermeasure to cope with thermal stratification effect on hot-leg piping that has been an unresolved issue in NPPs. By introducing ultrasonic technology, the average internal piping temperature can be measured with high accuracy. The inaccuracy can be decreased less than ±1℉ by this method.

Using Ultrasonic Lamb Waves To Measure Moduli Of Composites

Science.gov (United States)

Kautz, Harold E.

1995-01-01

Measurements of broad-band ultrasonic Lamb waves in plate specimens of ceramic-matrix/fiber and metal-matrix/fiber composite materials used to determine moduli of elasticity of materials. In one class of potential applications of concept, Lamb-wave responses of specimens measured and analyzed at various stages of thermal and/or mechanical processing to determine effects of processing, without having to dissect specimens. In another class, structural components having shapes supporting propagation of Lamb waves monitored ultrasonically to identify signs of deterioration and impending failure.

Combined cold compressor/ejector helium refrigerator cycle

International Nuclear Information System (INIS)

Schlafke, A.P.; Brown, D.P.; Wu, K.C.

1984-01-01

This chapter demonstrates how the use of a cold compressor in series with an ejector is an effective way to produce the desired low pressure in a helium refrigeration system. The cold compressor is tentatively located at the low pressure side below the J-T heat exchanger. The ejector is the first stage and the cold compressor is the second stage of the two-stage pumping system. A centrifugal, oil-bearing type compressor was installed on the R and D refrigerator at the Brookhaven National Laboratory. It is determined that the combined cold compressor and ejector system produces a lower temperature on the same load or more cooling at the same temperature compared with a system which uses an ejector alone. Results of the test showed a gain of 20%

A quality control method by ultrasonic vibration energy and diagnosis system at trimming process

International Nuclear Information System (INIS)

Suh, Chang Min; Song, Gil Ho; Pyoun, Young Shik

2007-01-01

In this paper, the characteristics in mechanical properties of ultrasonic cold forging treatment (UCFT) used for the trimming knife and the effects of ultrasonic vibration energy (UVE) into the trimming process on the state of the strip cutting face were studied. And a diagnosis system to quality control for trimming knife and strip cutting face was developed and installed in plant. By the plant application of UCFT, service life of knife was more increased over 100% than that of conventional knife and using the developed diagnosis system, the knife breakage and saw ear have been perfectly detected and quality control of trimming face is effectively obtained

Evaluation of the stages involved in cold ischemia time in renal transplants in Chile.

Science.gov (United States)

Elgueta, S; Fuentes, C; Arenas, A; Labraña, C; Gajardo, J G; Lopez, M; Hernandez, J; Rodriguez, H; Rodriguez, L

2010-01-01

Cold ischemia time (CIT) is one of the factors that determine the evolution of a renal transplant; taking measures to reduce this time requires knowledge of its stages. The objective of this study was to evaluate the times in the stages that determine CIT in renal transplants. We analyzed 108 donors and 201 kidney transplantations performed in Chile in 2008, establishing the CIT for the kidney transplanted by the center that extracted the kidneys (local kidney) and for the kidney transplanted in another center (shared kidney). Average CIT was 18.8 hours: namely, 16.9 hours for local and 20.2 hours for shared kidneys (P = .0001484). CIT for cases in which samples were sent to histocompatibility laboratory prior to nephrectomy was 7.3 hours less than for those sent postnephrectomy. The mean time between the allocation of the kidney and the transplant was 7.3 hours; 5.6 hours for local kidneys and 8.4 hours for shared kidneys (P = .000007124). We identified the stages at which intervention is possible to reduce the CIT, mainly for shared kidneys. All involved parties should make an effort to reduce this time.

Cold Sore

Science.gov (United States)

... may reduce how often they return. Symptoms A cold sore usually passes through several stages: Tingling and itching. Many people feel an itching, burning or tingling sensation around their lips for a day or so ...

Application of Ultrasonic Waves on Maintaining Freshness of Tilapia Fillet

Directory of Open Access Journals (Sweden)

Ruddy Suwandi

2015-06-01

Full Text Available ish fillet is one of fisheries products that easily deteriorated; hence handling techniques are needed to maintain the freshness. Ultrasonic wave have been widely applied to some of food products for maintaining freshness through microbial inactivation, however the ultrasonic application to fisheries products has not been reported. The purpose of this study was to analyze the effect of ultrasonic wave on fish freshness. The stages of the study were sample preparation, sonication, freshness parameters examination and histology observation. Ultrasonic wave did not affectthe organoleptic value and the TVB, but affected the pH value and the TPC. The sample in which the TPC value was found significantly different, were further observed after 48 and 96 hours storage. The result showed that the TPC value of sonicated sample for 9 minutes was lower to that of without sonication. Histology analysis showed, however, sonication made the structure of muscle fiber less compact and deformation of myomer was found.

Ultrasonic signature

International Nuclear Information System (INIS)

Borloo, E.; Crutzen, S.

1974-12-01

The unique and tamperproof identification technique developed at Ispra is based on ultrasonic Non-Destructive-Techniques. Reading fingerprints with ultrasonic requires high reproducibility of standard apparatus and transducers. The present report gives an exhaustive description of the ultrasonic technique developed for identification purposes. Different applications of the method are described

Industrial Applications of High Power Ultrasonics

Science.gov (United States)

Patist, Alex; Bates, Darren

Since the change of the millennium, high-power ultrasound has become an alternative food processing technology applicable to large-scale commercial applications such as emulsification, homogenization, extraction, crystallization, dewatering, low-temperature pasteurization, degassing, defoaming, activation and inactivation of enzymes, particle size reduction, extrusion, and viscosity alteration. This new focus can be attributed to significant improvements in equipment design and efficiency during the late 1990 s. Like most innovative food processing technologies, high-power ultrasonics is not an off-the-shelf technology, and thus requires careful development and scale-up for each and every application. The objective of this chapter is to present examples of ultrasonic applications that have been successful at the commercialization stage, advantages, and limitations, as well as key learnings from scaling up an innovative food technology in general.

Wireless cardiac action potential transmission with ultrasonically inserted silicon microprobes

International Nuclear Information System (INIS)

Shen, C J; Ramkumar, A; Lal, A; Gilmour, R F Jr

2011-01-01

This paper reports on the integration of ultrasonically inserted horn-shaped cardiac probes with wireless transmission of 3D cardiac action potential measurement for applications in ex vivo preparations such as monitoring the onset of ventricular fibrillation. Ultrasonically inserted silicon horn probes permit reduced penetration force during insertion, allowing silicon, a brittle material, to penetrate cardiac tissue. The probes also allow recording from multiple sites that are lithographically defined. An application-specific integrated circuit has been designed with a 40 dB amplifying stage and a frequency modulating oscillator at 95 MHz to wirelessly transmit the recorded action potentials. This ultrasonically inserted microprobe wireless system demonstrates the initial results in wireless monitoring of 3D action potential propagation, and the extraction of parameters of interest including the action potential duration and diastolic interval

Ultrasonic horn design for ultrasonic machining technologies

Directory of Open Access Journals (Sweden)

Naď M.

2010-07-01

Full Text Available Many of industrial applications and production technologies are based on the application of ultrasound. In many cases, the phenomenon of ultrasound is also applied in technological processes of the machining of materials. The main element of equipments that use the effects of ultrasound for machining technology is the ultrasonic horn – so called sonotrode. The performance of ultrasonic equipment, respectively ultrasonic machining technologies depends on properly designed of sonotrode shape. The dynamical properties of different geometrical shapes of ultrasonic horns are presented in this paper. Dependence of fundamental modal properties (natural frequencies, mode shapes of various sonotrode shapes for various geometrical parameters is analyzed. Modal analyses of the models are determined by the numerical simulation using finite element method (FEM design procedures. The mutual comparisons of the comparable parameters of the various sonotrode shapes are presented.

Radionuclide and ultrasonic investigations in liver cirrhosis with portal hypertension

International Nuclear Information System (INIS)

Khodzhibekov, M.Kh.; Rikhsieva, L.Eh.; Nazyrov, F.G.

1988-01-01

Combined radionuclide and ultrasonic investigations (UNI) were performed in 95 patients with liver cirrhosis complicated by portal hypertension. Liver and splenic shape structure and the presence of fluid in the abdominal cavity were assessed in USI. Radionuclide methods of investigation of the hepatic blood flow, assessment of the shape, size and structure of RP distribution in the liver and spleen, and for calculation of the hepatosplenic index. The most significant signs of differentiation of stages of portal hypertension were the presence and amount of fluid in the abdominal cavity and a hepatic blood flow value reflecting the gravity of portal hypertension. Combined radionuclide and ultrasonic investigations permitted a differentiated approach to staging of portal hypertension and assessment of liver and splenic morphofunctional state that could play an important role in the choice of tactics of surgery of liver cirrhosis

Radionuclide and ultrasonic investigations in liver cirrhosis with portal hypertension

Energy Technology Data Exchange (ETDEWEB)

Khodzhibekov, M Kh; Rikhsieva, L Eh; Nazyrov, F G

1988-08-01

Combined radionuclide and ultrasonic investigations (UNI) were performed in 95 patients with liver cirrhosis complicated by portal hypertension. Liver and splenic shape structure and the presence of fluid in the abdominal cavity were assessed in USI. Radionuclide methods of investigation of the hepatic blood flow, assessment of the shape, size and structure of RP distribution in the liver and spleen, and for calculation of the hepatosplenic index. The most significant signs of differentiation of stages of portal hypertension were the presence and amount of fluid in the abdominal cavity and a hepatic blood flow value reflecting the gravity of portal hypertension. Combined radionuclide and ultrasonic investigations permitted a differentiated approach to staging of portal hypertension and assessment of liver and splenic morphofunctional state that could play an important role in the choice of tactics of surgery of liver cirrhosis.

Ultrasonic cleaning of conveyor belt materials using Listeria monocytogenes as a model organism.

Science.gov (United States)

Tolvanén, Riina; Lunden, Janne; Korkeala, Hannu; Wirtanen, Gun

2007-03-01

Persistent Listeria monocytogenes contamination of food industry equipment is a difficult problem to solve. Ultrasonic cleaning offers new possibilities for cleaning conveyors and other equipment that are not easy to clean. Ultrasonic cleaning was tested on three conveyor belt materials: polypropylene, acetal, and stainless steel (cold-rolled, AISI 304). Cleaning efficiency was tested at two temperatures (30 and 45 degrees C) and two cleaning times (30 and 60 s) with two cleaning detergents (KOH, and NaOH combined with KOH). Conveyor belt materials were soiled with milk-based soil and L. monocytogenes strains V1, V3, and B9, and then incubated for 72 h to attach bacteria to surfaces. Ultrasonic cleaning treatments reduced L. monocytogenes counts on stainless steel 4.61 to 5.90 log units; on acetal, 3.37 to 5.55 log units; and on polypropylene, 2.31 to 4.40 log units. The logarithmic reduction differences were statistically analyzed by analysis of variance using Statistical Package for the Social Sciences software. The logarithmic reduction was significantly greater in stainless steel than in plastic materials (P conveyor belt materials.

Ultrasonic inspection

International Nuclear Information System (INIS)

Satittada, Gannaga

1984-01-01

Ultrasonic inspection is one of the most widely used methods for nondestructive inspection. The beam of high-frequency sound wave, ultrasonic wave, is introduced into the material. It travels through the material with some attendant loss of energy and can be reflected at interfaces. The reflected beam is detected and analyzed. Ultrasonic inspection is used to detect flaws in metal parts as well as in welded, brazed and bonded joints during research work and developing production and service. It is also used to detect and locate porosity, pipe, and flakes. In addition, it can be used for the measurement of metal thickness. Ultrasonic inspection is therefore used for quality control and material inspection in all major industries

Influence of a high vacuum on the precise positioning using an ultrasonic linear motor.

Science.gov (United States)

Kim, Wan-Soo; Lee, Dong-Jin; Lee, Sun-Kyu

2011-01-01

This paper presents an investigation of the ultrasonic linear motor stage for use in a high vacuum environment. The slider table is driven by the hybrid bolt-clamped Langevin-type ultrasonic linear motor, which is excited with its different modes of natural frequencies in both lateral and longitudinal directions. In general, the friction behavior in a vacuum environment becomes different from that in an environment of atmospheric pressure and this difference significantly affects the performance of the ultrasonic linear motor. In this paper, to consistently provide stable and high power of output in a high vacuum, frequency matching was conducted. Moreover, to achieve the fine control performance in the vacuum environment, a modified nominal characteristic trajectory following control method was adopted. Finally, the stage was operated under high vacuum condition, and the operating performances were investigated compared with that of a conventional PI compensator. As a result, robustness of positioning was accomplished in a high vacuum condition with nanometer-level accuracy.

Influence of a high vacuum on the precise positioning using an ultrasonic linear motor

International Nuclear Information System (INIS)

Kim, Wan-Soo; Lee, Dong-Jin; Lee, Sun-Kyu

2011-01-01

This paper presents an investigation of the ultrasonic linear motor stage for use in a high vacuum environment. The slider table is driven by the hybrid bolt-clamped Langevin-type ultrasonic linear motor, which is excited with its different modes of natural frequencies in both lateral and longitudinal directions. In general, the friction behavior in a vacuum environment becomes different from that in an environment of atmospheric pressure and this difference significantly affects the performance of the ultrasonic linear motor. In this paper, to consistently provide stable and high power of output in a high vacuum, frequency matching was conducted. Moreover, to achieve the fine control performance in the vacuum environment, a modified nominal characteristic trajectory following control method was adopted. Finally, the stage was operated under high vacuum condition, and the operating performances were investigated compared with that of a conventional PI compensator. As a result, robustness of positioning was accomplished in a high vacuum condition with nanometer-level accuracy.

Ultrasonic mammography

International Nuclear Information System (INIS)

Hueneke, B.

1982-01-01

608 women are examined by means of ultrasonic mammography during the period of 1 year. 432 patients were examined with the compound method with the U.I. Octoson, a water tank scanner, and 176 patients with the real time method with a directly connected linear-array-scanner. The following results were obtained at the end of the examination period: In the ultrasonic and also in the X-ray mammogram tumour diameters can be determined with an error rate of +- 30%. In the diagnosing of carcinomas, a significant dependence of the exactness on the sice of the tumour is found for the combination of the five methods tested (clinical examination, X-ray mammography, ultrasonic mammography, thermography, cytology). Classifying the individual methods with regard to their exactness, X-ray mammography ranks in front of ultrasonic mammography. Mastopathic changes in the breast can be screened by means of ultrasonic mammography. The structure of the changes can be determined more exactly than with an X-ray picture which is due to the possibility of differentiating solid and cystic structures. In diagnosing fibro-adenomas and establishing diagnoses on young women with dense gland bodies, ultrasonic mammography is superior to radiology both in the ability of screening a finding of a fibro-adenoma (US=88%, X-ray=75%) and in the possibility of classifying it as ''more benign than malignant''. (orig./MG) [de

Ultrasonic physics

CERN Document Server

Richardson, E G

1962-01-01

Ultrasonic Physics, Second Edition, provides an introduction to the fundamental principles of ultrasonic physics. The book opens with a discussion of the sources of ultrasound. This is followed by separate chapters on the properties and detection of ultrasonic radiation; measurement of propagation constants, i.e., the velocity and absorption, of ultrasound; ultrasound propagation in gases, liquids, and solids; and ultrasound propagation in aerosols, suspensions, and emulsions. The final chapter covers miscellaneous physical and physico-chemical actions, including dispersion and coagulation of

Effects of ultrasonic irradiation on crystallization and structural properties of EMT-type zeolite nanocrystals

Energy Technology Data Exchange (ETDEWEB)

Ng, Eng-Poh, E-mail: epng@usm.my [School of Chemical Sciences, Universiti Sains Malaysia, USM, 11800 Penang (Malaysia); Awala, Hussein [Laboratoire Catalyse & Spectrochimie, CNRS-ENSICAEN, Université de Caen (France); Ghoy, Jia-Pei [School of Chemical Sciences, Universiti Sains Malaysia, USM, 11800 Penang (Malaysia); Vicente, Aurélie [Laboratoire Catalyse & Spectrochimie, CNRS-ENSICAEN, Université de Caen (France); Ling, Tau Chuan [Institute of Biological Sciences, Faculty of Science, University of Malaya (Malaysia); Ng, Yun Hau [School of Chemical Engineering, The University of New South Wales, Sydney (Australia); Mintova, Svetlana [Laboratoire Catalyse & Spectrochimie, CNRS-ENSICAEN, Université de Caen (France); Adam, Farook, E-mail: farook@usm.my [School of Chemical Sciences, Universiti Sains Malaysia, USM, 11800 Penang (Malaysia)

2015-06-01

Synthesis of EMT zeolite nanocrystals from rice husk ash biomass (RHA) under continuous ultrasonic irradiation is reported. The aging, nucleation and crystallization stages of EMT zeolite in the system were monitored at ambient temperature, and compared with the conventional hydrothermal method. It was found that ultrasonic wave induced rapid crystal growth of the nanosized EMT zeolite. Complete crystallization of EMT nanocrystals was achieved within 24 h which was much faster than conventional hydrothermal synthesis (36 h). Furthermore, XRD and TEM analyses revealed that more nuclei were formed during the nucleation stage, allowing the preparation of smaller zeolite nanocrystals with high crystallinity. The results also showed that sonocrystallization produced EMT zeolite with high yield (ca. 80%). The ultrasound-prepared EMT nanocrystals were also found to have high porosity and high hydrophilicity, making the material promising for water sorption applications including vapor sensing, heat pump and adsorption technologies. - Highlights: • Nanosized EMT zeolites are formed from rice husk ash under ultrasonic irradiation. • The effects of ultrasonic waves in nanosized EMT zeolite synthesis are studied. • Ultrasound induces rapid crystal growth and produces high zeolite yield. • Smaller zeolite nanocrystals with high crystallinity and large defect sites are obtained. • Improved surface hydrophilicity of crystals is beneficial for water sorption applications.

Development of an ultrasonic pulse-echo (UPE) technique for aircraft icing studies

Energy Technology Data Exchange (ETDEWEB)

Liu, Yang; Hu, Hui [Department of Aerospace Engineering, Iowa State University, 2271 Howe Hall, Room 1200, Ames, IA 50011 (United States); Chen, Wen-Li [Department of Aerospace Engineering, Iowa State University, 2271 Howe Hall, Room 1200, Ames, IA 50011 (United States); School of Civil Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150090 (China); Bond, Leonard J. [Department of Aerospace Engineering, Iowa State University, 2271 Howe Hall, Room 1200, Ames, IA 50011 (United States); Center for Nondestructive Evaluation, Iowa State University, 1915 Scholl Road, 151 ASC II, Ames, IA 50011 (United States)

2014-02-18

Aircraft operating in some cold weather conditions face the risk of icing. Icing poses a threat to flight safety and its management is expensive. Removing light frost on a clear day from a medium-size business jet can cost $300, heavy wet snow removal can cost $3,000 and removal of accumulated frozen/freezing rain can cost close to $10,000. Understanding conditions that lead to severe icing events is important and challenging. When an aircraft or rotorcraft flies in a cold climate, some of the super cooled droplets impinging on exposed aircraft surfaces may flow along the surface prior to freezing and give various forms and shapes of ice. The runback behavior of a water film on an aircraft affects the morphology of ice accretion and the rate of formation. In this study, we report the recent progress to develop an Ultrasonic Pulse-Echo (UPE) technique to provide real-time thickness distribution measurements of surface water flows driven by boundary layer airflows for aircraft icing studies. A series of initial experimental investigations are conducted in an ice wind tunnel employing an array of ultrasonic transducers placed underneath the surface of a flat plate. The water runback behavior on the plate is evaluated by measuring the thickness profile variation of the water film along the surface by using the UPE technique under various wind speed and flow rate conditions.

Study of ultrasonic characterization and propagation in austenitic welds: The MOSAICS project

Energy Technology Data Exchange (ETDEWEB)

Chassignole, Bertrand, E-mail: bertrand.chassignole@edf.fr [EDF R and D, MMC department, Les Renardières, 77818 Moret sur Loing (France); Recolin, Patrick, E-mail: patrick.recolin@dcnsgroup.com [DCNS CESMAN, 44620 La montagne (France); Leymarie, Nicolas, E-mail: nicolas.leymarie@cea.fr [CEA LIST, 91191 Gif-sur-Yvette (France); Gueudré, Cécile, E-mail: cecile.gueudre@univ-amu.fr [LMA, Aix Marseille Université, CNRS, UPR 7051, F-13402 Marseille Cedex 20 (France); Guy, Philippe, E-mail: philippe.guy@insa-lyon.fr [INSA Lyon, LVA laboratory, 69621 Villeurbanne (France); Elbaz, Deborah, E-mail: deborah.elbaz@extende.com [Extende, 91400 Orsay (France)

2015-03-31

Regulatory requirements enforce a volumetric inspection of welded components of nuclear equipments. However, the multi-pass austenitic welds are characterized by anisotropic and heterogeneous structures which lead to numerous disturbances of the ultrasonic beam. The MOSAICS project supported by the ANR (French National Research Agency) aims at matching various approaches to improve the prediction of the ultrasonic testing in those welds. The first stage consists in characterizing the weld structure (determination of the columnar grain orientation and measurements of elastic constants and attenuation coefficients). The techniques of characterization provide input data for the modeling codes developed in another task of the project. For example, a 3D version of the finite elements code ATHENA is developed by EDF R and D to take into account anisotropic texture in any direction. Semi-analytical models included in CIVA software are also improved to better predict the ultrasonic propagation in highly anisotropic and heterogeneous structures. The last stage deals with modeling codes validation based on experimental inspections on representative mock-ups containing calibrated defects. The objective of this paper is to give an overview of the MOSAICS project and to present specific results illustrating the various tasks.

Effect of Ultrasonic Frequency on Lactic Acid Fermentation Promotion by Ultrasonic Irradiation

Science.gov (United States)

Shimada, Tadayuki; Ohdaira, Etsuzo; Masuzawa, Nobuyoshi

2004-05-01

The authors have been researching the promotion of lactic acid fermentation by ultrasonic irradiation. In the past research, it was proven that ultrasonic irradiation is effective in the process of fermentation, and the production of yoghurt and kefir was promoted. In this study, the effect of the ultrasonic frequency in this fermentation process was examined. In the frequency range of this study, it was found that the action of fermentation promotion was exponentially proportionate to the irradiated ultrasonic frequency.

Electromagnetic ultrasonic guided waves

CERN Document Server

Huang, Songling; Li, Weibin; Wang, Qing

2016-01-01

This book introduces the fundamental theory of electromagnetic ultrasonic guided waves, together with its applications. It includes the dispersion characteristics and matching theory of guided waves; the mechanism of production and theoretical model of electromagnetic ultrasonic guided waves; the effect mechanism between guided waves and defects; the simulation method for the entire process of electromagnetic ultrasonic guided wave propagation; electromagnetic ultrasonic thickness measurement; pipeline axial guided wave defect detection; and electromagnetic ultrasonic guided wave detection of gas pipeline cracks. This theory and findings on applications draw on the author’s intensive research over the past eight years. The book can be used for nondestructive testing technology and as an engineering reference work. The specific implementation of the electromagnetic ultrasonic guided wave system presented here will also be of value for other nondestructive test developers.

Ultrasonic viewing device

International Nuclear Information System (INIS)

Ito, Juro.

1979-01-01

Purpose: To improve the safety of reactor operation by enabling to detect the states and positions of fuel assemblies over a wide range with a set of ultrasonic viewing device comprising a rotatable ultrasonic transmitter-receiver and a reflector mounted with an adjustable angle. Constitution: A driving portion for a ultrasonic viewing device is provided to a rotary plug closing the opening of a reactor vessel and a guide pipe suspending below the coolant level is provided to the driving portion. An ultrasonic transmitter-receiver is provided at the end of the holder tube in the guide pipe. A reflector is provided at the upper position of the reactor core so as to correspond to the ultrasonic transmitter-receiver. The ultrasonic transmitter-receiver, positioned by the driving portion, performs horizontal movement for scanning the entire surface of the top of the reactor core, as well as vertical movement covering the gap between the upper mechanism on the reactor and the reactor core, whereby the confirmation for the separation of the control rod and the detection for the states of the reactor core can be conducted by the reflection waves from the reflector. (Moriyama, K.)

2D biological representations with reduced speckle obtained from two perpendicular ultrasonic arrays.

Science.gov (United States)

Rodriguez-Hernandez, Miguel A; Gomez-Sacristan, Angel; Sempere-Payá, Víctor M

2016-04-29

Ultrasound diagnosis is a widely used medical tool. Among the various ultrasound techniques, ultrasonic imaging is particularly relevant. This paper presents an improvement to a two-dimensional (2D) ultrasonic system using measurements taken from perpendicular planes, where digital signal processing techniques are used to combine one-dimensional (1D) A-scans were acquired by individual transducers in arrays located in perpendicular planes. An algorithm used to combine measurements is improved based on the wavelet transform, which includes a denoising step during the 2D representation generation process. The inclusion of this new denoising stage generates higher quality 2D representations with a reduced level of speckling. The paper includes different 2D representations obtained from noisy A-scans and compares the improvements obtained by including the denoising stage.

Radial vibration and ultrasonic field of a long tubular ultrasonic radiator.

Science.gov (United States)

Shuyu, Lin; Zhiqiang, Fu; Xiaoli, Zhang; Yong, Wang; Jing, Hu

2013-09-01

The radial vibration of a metal long circular tube is studied analytically and its electro-mechanical equivalent circuit is obtained. Based on the equivalent circuit, the radial resonance frequency equation is derived. The theoretical relationship between the radial resonance frequency and the geometrical dimensions is studied. Finite element method is used to simulate the radial vibration and the radiated ultrasonic field and the results are compared with those from the analytical method. It is concluded that the radial resonance frequency for a solid metal rod is larger than that for a metal tube with the same outer radius. The radial resonance frequencies from the analytical method are in good agreement with those from the numerical method. Based on the acoustic field analysis, it is concluded that the long metal tube with small wall thickness is superior to that with large wall thickness in producing radial vibration and ultrasonic radiation. Therefore, it is expected to be used as an effective radial ultrasonic radiator in ultrasonic sewage treatment, ultrasonic antiscale and descaling and other ultrasonic liquid handling applications. Copyright © 2013 Elsevier B.V. All rights reserved.

Ultrasonic decontamination robot

International Nuclear Information System (INIS)

Patenaude, R.S.

1984-01-01

An ultrasonic decontamination robot removes radioactive contamination from the internal surface of the inlet and outlet headers, divider plate, tube sheet, and lower portions of tubes of a nuclear power plant steam generator. A programmable microprocessor controller guides the movement of a robotic arm mounted in the header manway. An ultrasonic transducer having a solvent delivery subsystem through which ultrasonic action is achieved is moved by the arm over the surfaces. A solvent recovery suction tube is positioned within the header to remove solvent therefrom while avoiding interference with the main robotic arm. The solvent composition, temperature, pressure, viscosity, and purity are controlled to optimize the ultrasonic scrubbing action. The ultrasonic transducer is controlled at a power density, frequency, and on-off mode cycle such as to optimize scrubbing action within the range of transducer-to-surface distance and solvent layer thickness selected for the particular conditions encountered. Both solvent and transducer control actions are optimized by the programmable microprocessor. (author)

Ultrasonic testing device

International Nuclear Information System (INIS)

Lawrie, W.E.

1978-01-01

The ultrasonic transmitter made of polarized ferroelectric ceramic material (lead zirconate titanate) is arranged in a strip carrier which allows it to be introduced between the fuel elements of a fuel subassembly in a water cooled nuclear reactor. The ultrasonic transmitter is insulated relative to the carrier. The echo of the ra dal ultrasonic pulse is recorded which changes as faulty water filled fuel elements are detected. (RW) [de

Characterization of Aging Behavior in M250 Grade Maraging Steel Using Ultrasonic Measurements

Science.gov (United States)

Rajkumar, K. V.; Kumar, Anish; Jayakumar, T.; Raj, Baldev; Ray, K. K.

2007-02-01

Ultrasonic measurements have been carried out in M250 grade maraging steel specimens subjected to solution annealing at 1093 K for 1 hour followed by aging at 755 K for various durations in the range of 0.25 to 100 hours. The influence of aging on microstructure, room temperature hardness, and ultrasonic parameters (longitudinal and shear wave velocities and Poisson’s ratio) has been studied in order to derive correlations among these parameters in aged M250 maraging steel. Both hardness and ultrasonic velocities exhibit almost similar behaviors with aging time. They increase with the precipitation of intermetallic phases, Ni3Ti and Fe2Mo, and decrease with the reversion of martensite to austenite. Ultrasonic shear wave velocity is found to be more influenced by the precipitation of intermetallic phases, whereas longitudinal wave velocity is influenced more by the reversion of martensite to austenite. Unlike hardness and ultrasonic velocities, the Poisson’s ratio exhibits a monotonous decrease with aging time and, hence, can be used for unambiguous monitoring of the aging process in M250 maraging steel. Further, none of the parameters, i.e., hardness, ultrasonic velocity, or Poisson’s ratio, alone could identify the initiation of the reversion of austenite at early stage; however, the same could be identified from the correlation between ultrasonic velocity and Poisson’s ratio, indicating the advantage of using the multiparametric approach for comprehensive characterization of complex aging behavior in M250 grade maraging steel.

Recording length criteria as applied in ultrasonic testing

International Nuclear Information System (INIS)

Fischer, E.; Kroening, M.; Schober, H.; Fischdick, H.

1983-01-01

An appreciable method used to assess the quality and integrity of safety-related components in light water reactors is the ultrasonic examination, in which case great importance is attributed to the criteria pertaining to recording length and permissible defect size. The development of the recording length criteria as applied when employing this method of examination is portrayed, the latter being based on the criteria which have proven themselves throughout long years of practice in the examination of conventional components. When taking these criteria into account the application of conventional ultrasonic techniques often leads to problems in the case of thick-walled components the reason being that indications are overrated. Taking the design of reactor components as the basic point of consideration, modified criteria are derived particularly when the size of discontinuities calculated by fracture mechanics analyses is taken into account. The introduction of new ultrasonic examination techniques such as, for example, focussed probes revealed that a considerably more realistic assessment is possible and consequently results in a reduction of unnecessary repairs. A comparison of the size of indications determined using conventional and analytical technqiues renders possible the anchoring of an intermediate stage in the evaluation of indications which is encompassed in the consideration of the bundle divergence. Thus a new concept is realized for the evaluation of ultrasonic indications detected in reactor components, which in the meantime has found its way into the associated regulatory guides. (orig.)

Measurement of a 3D Ultrasonic Wavefield Using Pulsed Laser Holographic Microscopy for Ultrasonic Nondestructive Evaluation

Directory of Open Access Journals (Sweden)

Xing Wang

2018-02-01

Full Text Available In ultrasonic array imaging, 3D ultrasonic wavefields are normally recorded by an ultrasonic piezo array transducer. Its performance is limited by the configuration and size of the array transducer. In this paper, a method based on digital holographic interferometry is proposed to record the 3D ultrasonic wavefields instead of the array transducer, and the measurement system consisting of a pulsed laser, ultrasonic excitation, and synchronization and control circuit is designed. A consecutive sequence of holograms of ultrasonic wavefields are recorded by the system. The interferograms are calculated from the recorded holograms at different time sequence. The amplitudes and phases of the transient ultrasonic wavefields are recovered from the interferograms by phase unwrapping. The consecutive sequence of transient ultrasonic wavefields are stacked together to generate 3D ultrasonic wavefields. Simulation and experiments are carried out to verify the proposed technique, and preliminary results are presented.

Ultrasonic unit for line-by-line ultrasonic scanning of bodies

International Nuclear Information System (INIS)

Soldner, R.

1978-01-01

The ultrasonic unit for medical diagnostics operates by the sectorial scanning principle, which avoids direct coupling of the transducer head to the surface of the body. For this purpose, several transmitter/receiver units (approx. 100) are arranged on a partial ring of a circular arc and the ultrasonic beams, which can be triggered sequentially in time, are directed at a common intersection behind the ultrasonic window of the unit, i.e., outside the unit. A mechanical system is employed to set and adjust the partial ring carrying the transmitter/receiver units. (DG) [de

Control of molecular weight distribution in synthesis of poly(2-hydroxyethyl methacrylate) using ultrasonic irradiation.

Science.gov (United States)

Kubo, Masaki; Kondo, Takayuki; Matsui, Hideki; Shibasaki-Kitakawa, Naomi; Yonemoto, Toshikuni

2018-01-01

Poly(2-hydroxyethyl methacrylate) (PHEMA) was synthesized using ultrasonic irradiation without any chemical initiator. The effect of the ultrasonic power intensity on the time course of the conversion to polymer, the number average molecular weight, and the polydispersity were investigated in order to synthesize a polymer with a low molecular weight distribution (i.e., low polydispersity). The conversion to polymer increased with time. A higher ultrasonic power intensity resulted in a faster reaction rate. The number average molecular weight increased during the early stage of the reaction and then gradually decreased with time. A higher ultrasonic intensity resulted in a faster degradation rate of the polymer. The polydispersity decreased with time. This was because the degradation rate of a polymer with a higher molecular weight was faster than that of a polymer with a lower molecular weight. A polydispersity below 1.3 was obtained under ultrasonic irradiation. By changing the ultrasonic power intensity during the reaction, the number average molecular weight can be controlled while maintaining low polydispersity. When the ultrasonic irradiation was halted, the reactions stopped and the number average molecular weight and polydispersity did not change. On the basis of the experimental results, a kinetic model for synthesis of PHEMA under ultrasonic irradiation was constructed considering both polymerization and polymer degradation. The kinetic model was in good agreement with the experimental results for the time courses of the conversion to polymer, the number average molecular weight, and the polydispersity for various ultrasonic power intensities. Copyright © 2017 Elsevier B.V. All rights reserved.

Deconvolution algorithms applied in ultrasonics

International Nuclear Information System (INIS)

Perrot, P.

1993-12-01

In a complete system of acquisition and processing of ultrasonic signals, it is often necessary at one stage to use some processing tools to get rid of the influence of the different elements of that system. By that means, the final quality of the signals in terms of resolution is improved. There are two main characteristics of ultrasonic signals which make this task difficult. Firstly, the signals generated by transducers are very often non-minimum phase. The classical deconvolution algorithms are unable to deal with such characteristics. Secondly, depending on the medium, the shape of the propagating pulse is evolving. The spatial invariance assumption often used in classical deconvolution algorithms is rarely valid. Many classical algorithms, parametric and non-parametric, have been investigated: the Wiener-type, the adaptive predictive techniques, the Oldenburg technique in the frequency domain, the minimum variance deconvolution. All the algorithms have been firstly tested on simulated data. One specific experimental set-up has also been analysed. Simulated and real data has been produced. This set-up demonstrated the interest in applying deconvolution, in terms of the achieved resolution. (author). 32 figs., 29 refs

Resistivity recovery of neutron-irradiated and cold-worked thorium

International Nuclear Information System (INIS)

Tang, J.T.

1976-01-01

Recovery of neutron-irradiated and cold-worked thorium was studied using electrical resistivity measurements. Thorium wires containing 30 and 300 wt ppM carbon were irradiated to fast neutron fluence of 1.3 x 10 18 n/cm 2 (E greater than 0.1 MeV). Another group of thorium wires containing 45, 300 and 600 wt ppM carbon were laterally compressed 5 to 40 percent. Both irradiation and cold-working were performed at liquid nitrogen temperature. The induced resistivity was found to increase with carbon content for both treatments. Isochronal recovery studies were performed in the 120--420 0 K temperature range. Two recovery stages (II and III) were found for both cold-worked and irradiated samples. In all cases the activation energies were determined by use of the ratio-of-slope method. Consistent results were observed for both irradiated and cold-worked specimens within the experimental error in the two stages. Other methods were also used in determining the activation energy of stage III for irradiated samples. All analysis methods indicated that the activation energies decreased with increasing carbon content for differently treated specimens. Possible reasons for such behavior are discussed. The annealing data obtained do not fit a simple chemical rate equation but follow the empirical exponential equation proposed by Avrami. A model of detrapping of interstitials from impurities is suggested for stage II recovery. On the basis of the observed low activation energy and high retention of defects above stage III, a divacancy migration model is proposed for stage III recovery

Clinical and metabolic evaluation of one-stage, full-mouth, ultrasonic debridement as a therapeutic approach for uncontrolled type 2 diabetic patients with periodontitis.

Science.gov (United States)

Cirano, Fabiano Ribeiro; Pera, Claudia; Ueda, Paulo; Casarin, Renato Correa Viana; Ribeiro, Fernanda Vieira; Pimentel, Suzana Peres; Casati, Marcio Zaffalon

2012-09-01

To evaluate the therapeutic potential of one-stage, full-mouth, ultrasonic debridement (FMUD) as a treatment for type 2 diabetic patients with generalized severe chronic periodontitis. Sixteen patients diagnosed with generalized severe chronic periodontitis and type 2 diabetes mellitus were allocated to the diabetic group; another 15 subjects with periodontitis but without metabolic disorders were placed in the nondiabetic group. Both groups were treated using the FMUD protocol, a unique 45-minute session of ultrasonic debridement of all sites presenting periodontal disease. Patients were analyzed for the following parameters: plaque and bleeding indices, gingival recession, probing depth, and clinical attachment level. Further, diabetic subjects were assessed using fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c) tests. Patients were evaluated at 3 and 6 months for all parameters. ANOVA and the Tukey test were used for data analysis (P periodontal health after treatment. There were no significant differences between the groups for any of the parameters assessed (P > .05). Diabetic subjects treated with FMUD had a clinical response similar to that of nondiabetic subjects at all pocket depths. No adverse effects or medical disturbances were observed in either group during treatment. FPG and HbA1c levels remained unaltered after treatment. Within the limitations of this study, FMUD promoted clinical improvements in patients with type 2 uncontrolled diabetes and generalized severe chronic periodontitis.

Genetic Architecture of Cold Tolerance in Rice (Oryza sativa) Determined through High Resolution Genome-Wide Analysis

Science.gov (United States)

Cold temperature is an important abiotic stress which negatively affects morphological development and seed production in rice (Oryza sativa L.). At the seedling stage, cold stress causes poor germination, seedling injury and poor stand establishment; and at the reproductive stage cold decreases se...

Ultrasonic pretreatment of woodchips for the conversion of cellulose to glucose for bioethanol production

International Nuclear Information System (INIS)

Tutun Nugraha; Rettyana Ayuputri; Mohammad Ihsan

2010-01-01

In this study, lignocellulosic biomass i.e. the woodchips of Albacia tree (Paraserianthes falcataria) were given different pretreatment methods, i.e. chemical (acid) and physical (ultrasonic). The pretreatment was given in order to convert the cellulose to glucose for the production of bioethanol. 1 % H_2SO_4 was applied for the acid pretreatment. Ultrasound pretreatment was carried out at varied time (10, 20 and 30 minutes) at 600 W, 20 khz before or after the acid pretreatment. Enzymatic attack of the pretreated sample was also applied to enhance the saccharification process of cellulose. The objective of the research was to determine the most effective ultrasonic duration and the best combination of method for enzymatic hydrolysis of the woodchips. The data showed that the highest yield of glucose was achieved at 20 minutes ultrasonic time. It was also found that substantial amount of hydrolysis of cellulose to glucose occur during the ultrasonic stage even without the presence of acid or cellulose enzyme. It is likely that the highly energetic ultrasonic process alone could assist in enhancing rate of hydrolysis of lignocellulosic cellulose into glucose. (author)

Evaluation of Creep-Fatigue Damage in 304 Stainless Steel using Ultrasonic Non-Destructive Test

Energy Technology Data Exchange (ETDEWEB)

Lee, Sung Sik [Safetech Co. Ltd., Kimhae (Korea, Republic of); Oh, Yong Jun [Hanbat National Univ., Daejon (Korea, Republic of); Nam, Soo Woo [KISTI ReSEAT Program, Seoul (Korea, Republic of)

2011-12-15

It is well known that grain boundary cavitation is the main failure mechanism in austenitic stainless steel under tensile hold creep-fatigue interaction conditions. The cavities are nucleated at the grain boundary during cyclic loading and grow to become grain boundary cracks. The attenuation of ultrasound depends on scattering and absorption in polycrystalline materials. Scattering occurs when a propagation wave encounters microstructural discontinuities, such as internal voids or cavities. Since the density of the creepfatigue cavities increases with the fatigue cycles, the attenuation of ultrasound will also be increased with the fatigue cycles and this attenuation can be detected nondestructively. In this study, it is found that individual grain boundary cavities are formed and grow up to about 100 cycles and then, these cavities coalesce to become cracks. The measured ultrasonic attenuation increased with the cycles up to cycle 100, where it reached a maximum value and then decreased with further cycles. These experimental measurements strongly indicate that the open pores of cavities contribute to the attenuation of ultrasonic waves. However, when the cavities develop, at the grain boundary cracks whose crack surfaces are in contact with each other, there is no longer any open space and the ultrasonic wave may propagate across the cracks. Therefore, the attenuation of ultrasonic waves will be decreased. This phenomenon of maximum attenuation is very important to judge the stage of grain boundary crack development, which is the indication of the dangerous stage of the structures.

System for ultrasonic testing of welded seams. Einrichtung zur Ultraschallpruefung von Schweissnaehten

Energy Technology Data Exchange (ETDEWEB)

Bondarenko, J K; Troizkij, V A; Agronskaja, E V; Vasiliev, L N; Orel, V G; Naida, V L; Baldakov, V F; Ustjusanin, J V; Litvinenko, V A; Petrovskij, S N

1984-07-12

The invention concerns a device for the ultrasonic testing of welded joints which can be used in particular for quality control of multi-layer weldments. The testing equipment consists of probe, material testing device, amplitude discriminator, recording device, up and down counters and threshold value stages. (GSCH).

Cold temperatures increase cold hardiness in the next generation Ophraella communa beetles.

Directory of Open Access Journals (Sweden)

Zhong-Shi Zhou

Full Text Available The leaf beetle, Ophraella communa, has been introduced to control the spread of the common ragweed, Ambrosia artemisiifolia, in China. We hypothesized that the beetle, to be able to track host-range expansion into colder climates, can phenotypically adapt to cold temperatures across generations. Therefore, we questioned whether parental experience of colder temperatures increases cold tolerance of the progeny. Specifically, we studied the demography, including development, fecundity, and survival, as well as physiological traits, including supercooling point (SCP, water content, and glycerol content of O. communa progeny whose parents were maintained at different temperature regimes. Overall, the entire immature stage decreased survival of about 0.2%-4.2% when parents experienced cold temperatures compared to control individuals obtained from parents raised at room temperature. However, intrinsic capacity for increase (r, net reproductive rate (R 0 and finite rate of increase (λ of progeny O. communa were maximum when parents experienced cold temperatures. Glycerol contents of both female and male in progeny was significantly higher when maternal and paternal adults were cold acclimated as compared to other treatments. This resulted in the supercooling point of the progeny adults being significantly lower compared to beetles emerging from parents that experienced room temperatures. These results suggest that cold hardiness of O. communa can be promoted by cold acclimation in previous generation, and it might counter-balance reduced survival in the next generation, especially when insects are tracking their host-plants into colder climates.

Relative expression of genes related with cold tolerance in ...

African Journals Online (AJOL)

SAM

2014-06-18

Jun 18, 2014 ... Low temperature is one of the main abiotic stresses affecting rice yield in Chile. Alterations ... To find mechanisms of cold tolerance in Chilean cultivars, we ... dependent on the development stage and the intensity of the cold ...

Artificial Intelligence Assists Ultrasonic Inspection

Science.gov (United States)

Schaefer, Lloyd A.; Willenberg, James D.

1992-01-01

Subtle indications of flaws extracted from ultrasonic waveforms. Ultrasonic-inspection system uses artificial intelligence to help in identification of hidden flaws in electron-beam-welded castings. System involves application of flaw-classification logic to analysis of ultrasonic waveforms.

Ultrasonic grinding method

International Nuclear Information System (INIS)

Miyahara, Shuji.

1990-01-01

An ultrasonic generator and a liquid supply nozzle are opposed to an object to be ground and a pump is started in this state to supply an organic solvent. Matters to be decontaminated which adheres to the surface of the object to be ground and are difficult to be removed by a mere mechanical removing method can be eliminated previously by the surface active effect of the organic solvent such as ethanol prior to the oscillation of the ultrasonic generator. Subsequently, when the ultrasonic generator is oscillated, scales in the floated state can be removed simply. Further, since the organic solvent can penetrate to provide the surface active effect even in such a narrow portion that the top end of the ultrasonic generator is difficult to the intruded at the surface of the object to be ground, the decontaminating treatment can be applied also to such a narrow portion. (T.M.)

ULTRASONIC ASSEMBLY [REVIEW

Directory of Open Access Journals (Sweden)

PORAV Viorica

2015-05-01

Full Text Available The paper exposes the possibility of machine producesers to optimize the costs of clothes assembling. Ultrasonic systems being frequently utilized have many advantages on semi products of synthetic textile and technical textile. First of all, sewing – cutting process can be accomplished under high speeds and rate of losses can be minimized. Cutting seal applications are frequently used for underwear and sportswear. Slicing and unit cutting machines, as well as portable sealing machines are available for labeling sector. Products such as bag, pocket and cover can be sewed in a seamless manner for promotion purposes. All objects in terms of accessories are obtained in same standard. Our quilting machines are preferred in worldwide due to its threadless, high quality sealing. An alternative to the classic sewing assembly, with thread and needles is ultrasonic seaming. In ultrasonic welding, there are no connective bolts, nails, soldering materials, or adhesives necessary to bind the materials together. Ultrasonic is defined as acoustic frequencies above the range audible to the human ear. Ultrasonic frequencies are administered to the fabric from the sonotrode of bonding machine. The high frequency and powerful energy produced, when is release in one special environment, the ultrasound heating this environment. The ability to ultrasonic weld textiles and films depend on their thermoplastic contents and the desired end results. The paper defines the weld ability of more common textiles and films. The welding refers to all types of bonding and sealing, as in point bonding of fabric, or continuous sealing of film.

The effect of cold work on the recrystallization and precipitation kinetics of Al-Cu alloy

International Nuclear Information System (INIS)

Taha, A.S.; EL-Mossalamy, S.; Nassar, A.M.

1990-01-01

The effect of cold work by rolling (10-70%) followed by isochronal and isothermal annealing on the microhardness and iso thermal annealing on the microhardness and structure of Al-3.94 wt % Cu was investigated using microhardness measurements, optical and scanning electron microscopy. Two stages of annealing were observed, the first stage lies in the range R T-623 degree K is associated with decrease in hardness indicating overall recovery, while the second stage lies in the range 623-823 degree K shows hardness increase with temperature indicating precipitation reaching a maximum at 823 degree K for all cold worked specimens. The maximum hardness increases with the increase of the degree of cold work. The first stage is attributed to recovery processes including recrystallization while the second stage is attributed to precipitation which enhanced by increasing amount of cold work as indicated by hardness and scanning electron microscopy observations

Continuous ultrasonic waves to detect steam bubbles in water under high pressure

Energy Technology Data Exchange (ETDEWEB)

Hulshof, H J.M.; Schurink, F

1985-01-01

Steam in the recirculation circuit of boilers may lead to unacceptable high thermal loads on the evaporator tubes. The ability to detect steam in the recirculation circuit during process transients is therefore important. A simple detector using continuous ultrasonic waves and able to detect bubbles in water contained in steel tubes is described in this paper. The variation of the transmitted wave caused by the bubbles was determined by demodulation. The results have met the objectives set for cold water with air bubbles. A clear indication of the presence of steam bubbles was found in fast-flowing hot water in a steel tube with a diameter of 60 mm. A change in the low-frequency region of the modulation was the only indication of the presence of steam bubbles in the large-diameter downcomer of the water-separator drum of a boiler in an electrical power plant. Possible causes of the differences in the results obtained are discussed on the basis of differences in bubble sizes and in focusing and reflection of the ultrasonic waves. (orig.). 11 refs.; 10 figs.

Continuous ultrasonic waves to detect steam bubbles in water under high pressure

International Nuclear Information System (INIS)

Hulshof, H.J.M.; Schurink, F.

1985-01-01

Steam in the recirculation circuit of boilers may lead to unacceptable high thermal loads on the evaporator tubes. The ability to detect steam in the recirculation circuit during process transients is therefore important. A simple detector using continuous ultrasonic waves and able to detect bubbles in water contained in steel tubes is described in this paper. The variation of the transmitted wave caused by the bubbles was determined by demodulation. The results have met the objectives set for cold water with air bubbles. A clear indication of the presence of steam bubbles was found in fast-flowing hot water in a steel tube with a diameter of 60 mm. A change in the low-frequency region of the modulation was the only indication of the presence of steam bubbles in the large-diameter downcomer of the water-separator drum of a boiler in an electrical power plant. Possible causes of the differences in the results obtained are discussed on the basis of differences in bubble sizes and in focusing and reflection of the ultrasonic waves. (orig.)

Safe and efficient operation of multistage cold compressor systems

International Nuclear Information System (INIS)

Kauschke, M.; Haberstroh, C.; Quack, H.

1996-01-01

Large refrigeration rates in the temperature range of super fluid helium can only be obtained with the help of centrifugal cold compressors. For the large 2 K systems, four compression stages are necessary to reach atmospheric pressure. Centrifugal cold compressors are quite sensitive to mass flow and suction temperature variations; but these have to be expected in a real system. The first step in the systems design is to find safe and efficient quasi-stationary modes of operation. The system which is being proposed for the TESLA refrigerators relies on two features. The first is to allow the room temperature screw compressor, downstream of the cold compressors to work occasionally with a subatmospheric suction pressure. The second is to stabilize the suction temperature of the third stage of compression at about 10 K. With these features it is possible, that in all modes of operation all four compressor stages operate exactly at their design point

Effect of cold working on ordering of an equiatomic CuPt alloy

International Nuclear Information System (INIS)

Hisatsune, Kunihiro; Shiraishi, Takanobu; Takuma, Yasuko; Tanaka, Yasuhiro; Miura, Eri

2005-01-01

Effect of cold working on the ordering of an equiatomic CuPt alloy during continuous heating was studied by means of electrical resistivity measurements, hardness tests, differential scanning calorimetry, and X-ray diffraction. The ordering after cold working occurred in three stages with remarkable acceleration, namely, the migration and the annihilation of excess vacancies (I a ), those of secondary defects (I b ) and the migration of equilibrium vacancies (II) as well as that of quenched sample. The lattice defects introduced by cold working advanced the stages I a and I b , and therefore decreased the stage II. There existed two temperature regions with softening due to ordering enhanced recrystallization and normal recrystallization

Ultrasonic phased arrays for nondestructive inspection of forgings

International Nuclear Information System (INIS)

Wuestenberg, H.; Rotter, B.; Klanke, H.P.; Harbecke, D.

1993-01-01

Ultrasonic examinations on large forgings like rotor shafts for turbines or components for nuclear reactors are carried out at various manufacturing stages and during in-service inspections. During the manufacture, most of the inspections are carried out manually. Special in-service conditions, such as those at nuclear pressure vessels, have resulted in the development of mechanized scanning equipment. Ultrasonic probes have improved, and well-adapted sound fields and pulse shapes and based on special imaging procedures for the representation of the reportable reflectors have been applied. Since the geometry of many forgings requires the use of a multitude of angles for the inspections in-service and during manufacture, phased-array probes can be used successfully. The main advantages of the phased-array concept, e.g. the generation of a multitude of angles with the typical increase of redundancy in detection and quantitative evaluation and the possibility to produce pictures of defect situations, will be described in this contribution

Remote consulting based on ultrasonic digital immages and dynamic ultrasonic sequences

Science.gov (United States)

Margan, Anamarija; Rustemović, Nadan

2006-03-01

Telematic ultrasonic diagnostics is a relatively new tool in providing health care to patients in remote, islolated communities. Our project facility, "The Virtual Polyclinic - A Specialists' Consulting Network for the Islands", is located on the island of Cres in the Adriatic Sea in Croatia and has been extending telemedical services to the archipelago population since 2000. Telemedicine applications include consulting services by specialists at the University Clinical Hospital Center Rebro in Zagreb and at "Magdalena", a leading cardiology clinic in Croatia. After several years of experience with static high resolution ultrasonic digital immages for referral consulting diagnostics purposes, we now also use dynamic ultrasonic sequences in a project with the Department of Emmergency Gastroenterology at Rebro in Zagreb. The aim of the ongoing project is to compare the advantages and shortcomings in transmitting static ultrasonic digital immages and live sequences of ultrasonic examination in telematic diagnostics. Ultrasonic examination is a dynamic process in which the diagnostic accuracy is highly dependent on the dynamic moment of an ultrasound probe and signal. Our first results indicate that in diffuse parenchymal organ pathology the progression and the follow up of a disease is better presented to a remote consulting specialist by dynamic ultrasound sequences. However, the changes that involve only one part of a parenchymal organ can be suitably presented by static ultrasonic digital images alone. Furthermore, we need less time for digital imaging and such tele-consultations overall are more economical. Our previous telemedicine research and practice proved that we can greatly improve the level of medical care in remote healthcare facilities and cut healthcare costs considerably. The experience in the ongoing project points to a conclusion that we can further optimize remote diagnostics benefits by a right choice of telematic application thus reaching a

Ultrasonic flow meter

NARCIS (Netherlands)

Lötters, Joost Conrad; Snijders, G.J.; Volker, A.W.F.

2014-01-01

The invention relates to an ultrasonic flow meter comprising a flow tube for the fluid whose flow rate is to be determined. The flow meter comprises a transmitting element for emitting ultrasonic waves, which is provided on the outer jacket of the flow tube. A receiving element, which is provided on

A Delay Time Measurement of ULTRAS (Ultra-high Temperature Ultrasonic Response Analysis System) for a High Temperature Experiment

International Nuclear Information System (INIS)

Koo, Kil Mo; Kim, Sang Baik

2010-01-01

The temperature measurement of very high temperature core melt is of importance in a high temperature as the molten pool experiment in which gap formation between core melt and the reactor lower head, and the effect of the gap on thermal behavior are to be measured. The existing temperature measurement techniques have some problems, which the thermocouple, one of the contact methods, is restricted to under 2000 .deg. C, and the infrared thermometry, one of the non-contact methods, is unable to measure an internal temperature and very sensitive to the interference from reacted gases. In order to solve these problems, the delay time technique of ultrasonic wavelets due to high temperature has two sorts of stage. As a first stage, a delay time measurement of ULTRAS (Ultra-high Temperature Ultrasonic Response Analysis System) is suggested. As a second stage, a molten material temperature was measured up to 2300 .deg. C. Also, the optimization design of the UTS (ultrasonic temperature sensor) with persistence at the high temperature was suggested in this paper. And the utilization of the theory suggested in this paper and the efficiency of the developed system are performed by special equipment and some experiments supported by KRISS (Korea Research Institute of Standard and Science)

Two-stage absorber systems - Economically viable combined heat and cold generation; Wirtschaftlicher Kraft-Waerme-Kaelte-Verbund

Energy Technology Data Exchange (ETDEWEB)

Biniossek, H. [Giesecke und Devrient, Muenchen (Germany); Schmid, W. [Technische Gebaeudeausruestung, Muenchen (Germany)

2008-07-01

This article takes a look at how the possibilities of optimising power, heat and cold generation for the German Giesecke and Devrient company were examined and implemented. The company, which produces banknotes and chip-cards, chose the combination of a Combined Heat and Power (CHP) Unit and a two-stage absorber refrigeration system. The company's old system is briefly described and the reasons for replacing it are discussed. The careful dimensioning of the new system and the search for appropriate equipment are described. Intelligent power flows and a cooling system with two different temperature levels are described. Costs saved and emergency power generation are also looked at, as are the complex demands placed on the control of the system. The system's functioning is briefly described.

Ultrasonic Low-Friction Containment Plate for Thermal and Ultrasonic Stir Weld Processes

Science.gov (United States)

Graff, Karl; Short, Matt

2013-01-01

The thermal stir welding (TSW) process is finding applications in fabrication of space vehicles. In this process, workpieces to be joined by TSW are drawn, by heavy forces, between "containment plates," past the TSW tool that then causes joining of the separate plates. It is believed that the TSW process would be significantly improved by reducing the draw force, and that this could be achieved by reducing the friction forces between the workpieces and containment plates. Based on use of high-power ultrasonics in metal forming processes, where friction reduction in drawing dies has been achieved, it is believed that ultrasonic vibrations of the containment plates could achieve similar friction reduction in the TSW process. By applying ultrasonic vibrations to the containment plates in a longitudinal vibration mode, as well as by mounting and holding the containment plates in a specific manner such as to permit the plates to acoustically float, friction between the metal parts and the containment plates is greatly reduced, and so is the drawing force. The concept was to bring in the ultrasonics from the sides of the plates, permitting the ultrasonic hardware to be placed to the side, away from the equipment that contains the thermal stir tooling and that applies clamping forces to the plates. Tests demonstrated that one of the major objectives of applying ultrasonics to the thermal stir system, that of reducing draw force friction, should be achievable on a scaled-up system.

Computer-controlled ultrasonic equipment for automatic inspection of nuclear reactor components after manufacturing

International Nuclear Information System (INIS)

Moeller, P.; Roehrich, H.

1983-01-01

After foundation of the working team ''Automated US-Manufacture Testing'' in 1976 the realization of an ultrasonic test facility for nuclear reactor components after manufacturing has been started. During a period of about 5 years, an automated prototype facility has been developed, fabricated and successfully tested. The function of this facility is to replace the manual ultrasonic tests, which are carried out autonomically at different stages of the manufacturing process and to fulfil the test specification under improved economic conditions. This prototype facility has been designed as to be transported to the components to be tested at low expenditure. Hereby the reproduceability of a test is entirely guaranteed. (orig.) [de

Long-Range Piping Inspection by Ultrasonic Guided Waves

International Nuclear Information System (INIS)

Joo, Young Sang; Lim, Sa Hoe; Eom, Heung Seop; Kim, Jae Hee

2005-01-01

The ultrasonic guided waves are very promising for the long-range inspection of large structures because they can propagate a long distance along the structures such as plates, shells and pipes. The guided wave inspection could be utilized for an on-line monitoring technique when the transmitting and receiving transducers are positioned at a remote point on the structure. The received signal has the information about the integrity of the monitoring area between the transmitting and receiving transducers. On-line monitoring of a pipe line using an ultrasonic guided wave can detect flaws such as corrosion, erosion and fatigue cracking at an early stage and collect useful information on the flaws. However the guided wave inspection is complicated by the dispersive characteristics for guided waves. The phase and group velocities are a function of the frequency-thickness product. Therefore, the different frequency components of the guided waves will travel at different speeds and the shape of the received signal will changed as it propagates along the pipe. In this study, we analyze the propagation characteristics of guided wave modes in a small diameter pipe of nuclear power plant and select the suitable mode for a long-range inspection. And experiments will be carried out for the practical application of a long-range inspection in a 26m long pipe by using a high-power ultrasonic inspection system

Computer automation of ultrasonic testing. [inspection of ultrasonic welding

Science.gov (United States)

Yee, B. G. W.; Kerlin, E. E.; Gardner, A. H.; Dunmyer, D.; Wells, T. G.; Robinson, A. R.; Kunselman, J. S.; Walker, T. C.

1974-01-01

Report describes a prototype computer-automated ultrasonic system developed for the inspection of weldments. This system can be operated in three modes: manual, automatic, and computer-controlled. In the computer-controlled mode, the system will automatically acquire, process, analyze, store, and display ultrasonic inspection data in real-time. Flaw size (in cross-section), location (depth), and type (porosity-like or crack-like) can be automatically discerned and displayed. The results and pertinent parameters are recorded.

Ultrasonic inspection of austenitic welds

International Nuclear Information System (INIS)

Baikie, B.L.; Wagg, A.R.; Whittle, M.J.; Yapp, D.

1976-01-01

The ultrasonic examination of austenitic stainless steel weld metal has always been regarded as a difficult proposition because of the large and variable ultrasonic attenuations and back scattering obtained from apparently similar weld deposits. The work to be described shows how the existence of a fibre texture within each weld deposit (as a result of epitaxial growth through successive weld beads) produces a systematic variation in the ultrasonic attenuation coefficient and the velocity of sound, depending upon the angle between the ultrasonic beam and the fibre axis. Development work has shown that it is possible to adjust the welding parameters to ensure that the crystallographic texture within each weld is compatible with improved ultrasonic transmission. The application of the results to the inspection of a specific weld in type 316 weld metal is described

Irradiation Testing of Ultrasonic Transducers

International Nuclear Information System (INIS)

Daw, J.; Rempe, J.; Palmer, J.; Tittmann, B.; Reinhardt, B.; Kohse, G.; Ramuhalli, P.; Montgomery, R.; Chien, H.T.; Villard, J.F.

2013-06-01

Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of numerous parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 10 21 n/cm 2 (E> 0.1 MeV). This test will be an instrumented lead test; and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. By characterizing magnetostrictive and piezoelectric transducer survivability during irradiation, test results will enable the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. (authors)

Ultrasonic dip seal maintenance system

International Nuclear Information System (INIS)

Poindexter, A.M.; Ricks, H.E.

1978-01-01

Disclosed is a system for removing impurities from the surfaces of liquid dip seals and for wetting the metal surfaces of liquid dip seals in nuclear components. The system comprises an ultrasonic transducer that transmits ultrasonic vibrations along an ultrasonic probe to the metal and liquid surfaces of the dip seal thereby loosening and removing those impurities

Molecular weight kinetics and chain scission models for dextran polymers during ultrasonic degradation.

Science.gov (United States)

Pu, Yuanyuan; Zou, Qingsong; Hou, Dianzhi; Zhang, Yiping; Chen, Shan

2017-01-20

Ultrasonic degradation of six dextran samples with different initial molecular weights (IMW) has been performed to investigate the degradation behavior and chain scission mechanism of dextrans. The weight-average molecular weight (Mw) and polydispersity index (D value) were monitored by High Performance Gel Permeation Chromatography (HPGPC). Results showed that Mw and D value decreased with increasing ultrasonic time, resulting in a more homologous dextran solution with lower molecular weight. A significant degradation occurred in dextrans with higher IMW, particularly at the initial stage of the ultrasonic treatment. The Malhotra model was found to well describe the molecular weight kinetics for all dextran samples. Experimental data was fitted into two chain scission models to study dextran chain scission mechanism and the model performance was compared. Results indicated that the midpoint scission model agreed well with experimental results, with a linear regression factor of R 2 >0.99. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of ultrasonic treatment on the physico-chemical parameters of kvass

Directory of Open Access Journals (Sweden)

V. A. Demchenko

2016-01-01

Full Text Available In this paper, for the intensification of production kvass process are encouraged to use the installation "Wave-M" UZTA-1/22-OM sonication product. The aim of the experiment was to study the effect of treatment of process water and the yeast suspension with ultrasound in the production of kvass. To achieve its objectives for the Department of technological machinery and equipment ITMO University experimental setup was designed. In the course of the experiment we studied the effect of ultrasonic treatment on the physico-chemical characteristics of the finished beverage, made in different formulations, depending on the tiered effect of ultrasound. Organoleptic evaluation of the product was carried out, and active acidity measured amount of dry matter in the finished beverage. When processing kvass ultrasound power of 60 and 90 W at a tasting in the product became noticeable pleasant caramel flavor. Due to this effect may be replaced in the production of soft drinks expensive equipment used for cooking in sugar syrup tinting siropovarochnyh, kolerovarochnyh boilers cheaper ultrasonic unit. The acidity of the samples increased within acceptable limits. On the amount of solids in kvass ultrasonic treatment did not significantly affected. To increase the shelf life of the beverage used microfiltration. Anticipated acceleration of the process of obtaining fermented kvass 2 times. It is shown that the filtration using the dosing of ultrasound in the production of kvass not only reduce the cost of the equipment and remove some of the tra-ditional processes, but also provide with the cold sterilization of kvass with higher quality indicators.

Microstructure Characterization and Hardness Evaluation of Alloy 52 Welded Stainless Steel 316 Subjected to Ultrasonic Nanocyrtal Surface Modification Technique

Energy Technology Data Exchange (ETDEWEB)

Kim, H. D.; Amanov, A.; Pyun, Y. S. [Sun Moon Univ., Asan (Korea, Republic of); Kim, Y. S.; Choi, Y. S. [Andong National Univ., Andong (Korea, Republic of)

2015-10-15

In this study, an ultrasonic nanocrystal surface modification (UNSM) technique was applied to dissimilar weld point between STS316L and Alloy 52. This UNSM technique is a patented technology, which can be described as a type of ultrasonic cold-forging technology. It has been demonstrated that the UNSM technique is a simple method to produce a nanocrystalline surface layer at the top surface of metallic materials. Microstructure and hardness of STS316L and Alloy 52 are investigated before and after UNSM treatment. It is expected according to the previous study that the UNSM technique is able to release the residual stress which delays PWSCC. In this study, microstructural characterization and hardness evaluation of STS316L and welded Alloy 52 subjected to UNSM technique were investigated.

Ultrasonic neuromodulation

Science.gov (United States)

Naor, Omer; Krupa, Steve; Shoham, Shy

2016-06-01

Ultrasonic waves can be non-invasively steered and focused into mm-scale regions across the human body and brain, and their application in generating controlled artificial modulation of neuronal activity could therefore potentially have profound implications for neural science and engineering. Ultrasonic neuro-modulation phenomena were experimentally observed and studied for nearly a century, with recent discoveries on direct neural excitation and suppression sparking a new wave of investigations in models ranging from rodents to humans. In this paper we review the physics, engineering and scientific aspects of ultrasonic fields, their control in both space and time, and their effect on neuronal activity, including a survey of both the field’s foundational history and of recent findings. We describe key constraints encountered in this field, as well as key engineering systems developed to surmount them. In closing, the state of the art is discussed, with an emphasis on emerging research and clinical directions.

Ultrasonic vibration imposed on nanoparticle-based ZnO film improves the performance of the ensuing perovskite solar cell

Science.gov (United States)

Miao, Yihe; Du, Peng; Wang, Zhiyu; Chen, Qianli; Eslamian, Morteza

2018-02-01

This work focuses on the development of nearly annealing-free ZnO-based perovskite solar cells (PSCs), suitable for low-cost manufacturing of PSCs on flexible substrates. To this end, thin film of ZnO nanoparticles is employed as the electron transporting layer (ETL), because of its low-temperature solution-processability and high electron mobility. In order to remove the structural and surface defects, ultrasonic vibration is imposed on the substrate of the as-spun wet ZnO films for a short duration of 3 min. It is shown that the ultrasonic excitation bridges the ZnO nanoparticles (cold sintering), and brings about significant improvement in the ZnO film nanostructure and functionality. In addition, ethyl acetate (EA), as an emerging volatile anti-solvent, is employed to deposit the methylammonium (MA) lead halide perovskite thin film atop the ZnO ETL, in order to prepare perovskite layers that only need an annealing time of 30 s. The ZnO-based PSCs, with a simple structure and free of additional treatments, except for the ultrasonic vibration, exhibit a promising performance with a power conversion efficiency (PCE) of over 11%, 40% higher than that of the control device. The ultrasonic vibration treatment is facile, low-cost, environmentally friendly, and compatible with the scalable coating and printing techniques, such as spray and blade coating.

Ultrasonic colour Doppler imaging

DEFF Research Database (Denmark)

Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

2011-01-01

Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...

Ultrasonic flowmeters

International Nuclear Information System (INIS)

Wittekind, W.D.

1979-01-01

A prototype ultrasonic flowmeter was assembled and tested. The theoretical basis of this prototype ultrasonic flowmeter is reviewed; the equipment requirements for a portable unit are discussed; the individual electronic modules contained in the prototype are described; the operating procedures and configuration are explained; and the data from preliminary calibrations are presented. The calibration data confirm that the prototype operates according to theoretical predictions and can indeed provide nonintrusive flow measurements to predicted accuracies for pipes larger than two inches, under single phase stable flow conditions

Pulsed ultrasonic stir welding system

Science.gov (United States)

Ding, R. Jeffrey (Inventor)

2013-01-01

An ultrasonic stir welding system includes a welding head assembly having a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. During a welding operation, ultrasonic pulses are applied to the rod as it rotates about its longitudinal axis. The ultrasonic pulses are applied in such a way that they propagate parallel to the longitudinal axis of the rod.

Ultrasonic stir welding process and apparatus

Science.gov (United States)

Ding, R. Jeffrey (Inventor)

2009-01-01

An ultrasonic stir welding device provides a method and apparatus for elevating the temperature of a work piece utilizing at least one ultrasonic heater. Instead of relying on a rotating shoulder to provide heat to a workpiece an ultrasonic heater is utilized to provide ultrasonic energy to the workpiece. A rotating pin driven by a motor assembly performs the weld on the workpiece. A handheld version can be constructed as well as a fixedly mounted embodiment.

A pulse tube cryocooler with a cold reservoir

Science.gov (United States)

Zhang, X. B.; Zhang, K. H.; Qiu, L. M.; Gan, Z. H.; Shen, X.; Xiang, S. J.

2013-02-01

Phase difference between pressure wave and mass flow is decisive to the cooling capacity of regenerative cryocoolers. Unlike the direct phase shifting using a piston or displacer in conventional Stirling or GM cryocoolers, the pulse tube cyocooler (PTC) indirectly adjusts the cold phase due to the absence of moving parts at the cold end. The present paper proposed and validated theoretically and experimentally a novel configuration of PTC, termed cold reservoir PTC, in which a reservoir together with an adjustable orifice is connected to the cold end of the pulse tube. The impedance from the additional orifice to the cold end helps to increase the mass flow in phase with the pressure wave at the cold end. Theoretical analyses with the linear model for the orifice and double-inlet PTCs indicate that the cooling performance can be improved by introducing the cold reservoir. The preliminary experiments with a home-made single-stage GM PTC further validated the results on the premise of minor opening of the cold-end orifice.

Imaging techniques for ultrasonic testing

International Nuclear Information System (INIS)

2013-01-01

These seminar proceedings contain 16 lectures on the following topics: 1. From imaging to quantification - ultrasound methods in medical diagnostics; 2. SAFT, TOFD, Phased Array - classical applications and recent developments in ultrasonic imaging; 3. Innovative ultrasonic imaging methods in research and application; 4. Industrial ultrasonic testing of fibre-reinforced structures of complex geometry; 5. Visualisation of crack tips in the inspection of wheel set shafts with longitudinal boreholes as a means of avoiding unnecessary wheel set changes; 6. Areal analysis of the propagation of Lamb waves on curved, anisotropic structures; 7. High-resolution representation in immersion technique testing; 8. Variants in generating images from phased array measurement data - practical examples involving copper, carbon-fibre reinforced plastic and other materials; 9. GIUM - an unconventional method of microstructure imaging using ultrasonic stimulation and laser vibrometry scanning; 10. Innovative air-ultrasonic testing concepts for improved imaging; 11. Use of imaging methods for improving the quality of test results from nondestructive testing; 12. Modelling and visualisation of EMUS stimulation for transducer optimisation; 13. Use of SAFT in the manufacture of energy conversion machines; 14. Ultrasonic imaging tests for improved defect characterisation during weld seam inspection on longitudinally welded large-diameter pipes; 15. SAFT reconstruction for testing austenitic weld seams and dissimilar metal weld seams for transverse cracks; 16. Imaging-based optimisation method for quantitative ultrasonic testing of anisotropic inhomogeneous austenitic welded joints with determination and utilisation of their elastic properties. One contribution has been abstracted separately. [de

A self-running standing wave-type bidirectional slider for the ultrasonically levitated thin linear stage.

Science.gov (United States)

Koyama, Daisuke; Takei, Hiroyuki; Nakamura, Kentaro; Ueha, Sadayuki

2008-08-01

A slider for a self-running standing wave-type, ultrasonically levitated, thin linear stage is discussed. The slider can be levitated and moved using acoustic radiation force and acoustic streaming. The slider has a simple configuration and consists of an aluminum vibrating plate and a piezoelectric zirconate titanate (PZT) element. The large asymmetric vibration distribution for the high thrust and levitation performance was obtained by adjusting the configuration determined by finite elemental analysis (FEA). As a preliminary step, the computed results of the sound pressure distribution in the 1-mm air gap by FEA was com pared with experimental results obtained using a fiber optic probe. The direction of the total driving force for the acoustic streaming in the small air gap was estimated by the sound pressure distribution calculated by FEA, and it was found that the direction of the acoustic streaming could be altered by controlling the vibration mode of the slider. The flexural standing wave could be generated along the vibrating plate near the frequencies predicted based on the FEA results. The slider could be levitated by the acoustic radiation force radiated from its own vibrating plate at several frequencies. The slider could be moved in the negative and positive directions at 68 kHz and 69 kHz, which correspond to the results computed by FEA, with the asymmetric vibration distribution of the slider's vibrating plate. Larger thrust could be obtained with the smaller levitation distance, and the maximum thrust was 19 mN.

3D printed components with ultrasonically arranged microscale structure

Science.gov (United States)

Llewellyn-Jones, Thomas M.; Drinkwater, Bruce W.; Trask, Richard S.

2016-02-01

This paper shows the first application of in situ manipulation of discontinuous fibrous structure mid-print, within a 3D printed polymeric composite architecture. Currently, rapid prototyping methods (fused filament fabrication, stereolithography) are gaining increasing popularity within the engineering commnity to build structural components. Unfortunately, the full potential of these components is limited by the mechanical properties of the materials used. The aim of this study is to create and demonstrate a novel method to instantaneously orient micro-scale glass fibres within a selectively cured photocurable resin system, using ultrasonic forces to align the fibres in the desired 3D architecture. To achieve this we have mounted a switchable, focused laser module on the carriage of a three-axis 3D printing stage, above an in-house ultrasonic alignment rig containing a mixture of photocurable resin and discontinuous 14 μm diameter glass fibre reinforcement(50 μm length). In our study, a suitable print speed of 20 mm s-1 was used, which is comparable to conventional additive layer techniques. We show the ability to construct in-plane orthogonally aligned sections printed side by side, where the precise orientation of the configurations is controlled by switching the ultrasonic standing wave profile mid-print. This approach permits the realisation of complex fibrous architectures within a 3D printed landscape. The versatile nature of the ultrasonic manipulation technique also permits a wide range of particle types (diameters, aspect ratios and functions) and architectures (in-plane, and out-plane) to be patterned, leading to the creation of a new generation of fibrous reinforced composites for 3D printing.

Designing and Evaluating an Ultrasonic System for Identification of Weed Species

Directory of Open Access Journals (Sweden)

danial gandomzadeh

2016-09-01

Full Text Available Introduction: Considering the importance of healthy and inexpensive agricultural production, it is necessary to seek ways for precisely discrimination of weeds in the field to minimize the use of herbicides. In this research the feasibility of weed detection due to the reflected ultrasonic waves from some common weeds including Portulacaceae, Chenopodium album L, Tribulus terrestris L, Amaranthus retroflexus L and Salsola iberica, was investigated. Materials and Methods: An electronic circuit with several parts such as a microcontroller, a power supply (5 DC volts, a RS-232 output port, and an ultrasonic wave generator and detector was constructed. It emits a 40 KHz ultrasonic wave and receives the recursive wave which is reflected from the weed canopy. It can be mounted on an adjustable tripod that is aligned along the three main directions (X, Y, and Z and can also be turned around the X axis. The data acquisition was accomplished in the research field of the College of Agriculture, Ferdowsi University of Mashhad. The experiments were performed by mounting the system at constant height of 4 cm from the crop canopy. To avoid interfering of the recursive wave with the emitted wave, the generator and the detector were placed far apart. For each experiment the temperature and the relative humidity were recorded in a check list. For the Neural Network the so called BDLRF algorithm was used for training the network and started with a relatively constant large step size of learning rate and momentum term . Before destabilizing the network or when the convergence is slowed down, these values are decreased monotonically (22. In this study Double Sequential Classification Method was used for weed discrimination. This classification method can better simulate the human procedure for classification of different objects, from each other. The human being at the first stage, and based on some distinguishable criteria classifies the things into some main

Evaluation of Early-Age Concrete Compressive Strength with Ultrasonic Sensors.

Science.gov (United States)

Yoon, Hyejin; Kim, Young Jin; Kim, Hee Seok; Kang, Jun Won; Koh, Hyun-Moo

2017-08-07

Surface wave velocity measurement of concrete using ultrasonic sensors requires testing on only one side of a member. Thus, it is applicable to concrete cast inside a form and is often used to detect flaws and evaluate the compressive strength of hardened concrete. Predicting the in situ concrete strength at a very early stage inside the form helps with determining the appropriate form removal time and reducing construction time and costs. In this paper, the feasibility of using surface wave velocities to predict the strength of in situ concrete inside the form at a very early stage was evaluated. Ultrasonic sensors were used to measure a series of surface waves for concrete inside a form in the first 24 h after placement. A continuous wavelet transform was used to compute the travel time of the propagating surface waves. The cylindrical compressive strength and penetration resistance tests were also performed during the test period. Four mixtures and five curing temperatures were used for the specimens. The surface wave velocity was confirmed to be applicable to estimating the concrete strength at a very early age in wall-like elements. An empirical formula is proposed for evaluating the early-age compressive strength of concrete considering the 95% prediction intervals.

Full-field ultrasonic inspection for a composite sandwich plate skin-core debonding detection using laser-based ultrasonics

Science.gov (United States)

Chong, See Yenn; Victor, Jared J.; Todd, Michael D.

2017-04-01

In this paper, a full-field ultrasonic guided wave method is proposed to inspect a composite sandwich specimen made for an aircraft engine nacelle. The back skin/core interface of the specimen is built with two fabricated disbond defects (diameters of 12.7 mm and 25.4 mm) by removing areas of the adhesive used to bond the back skin to the core. A laser ultrasonic interrogation system (LUIS) incorporated with a disbond detection algorithm is developed. The system consists of a 1-kHz laser ultrasonic scanning system and a single fixed ultrasonic sensor to interrogate ultrasonic guided waves in the sandwich specimen. The interest area of 400 mm × 400 mm is scanned at a 0.5 mm scan interval. The corresponding full-field ultrasonic data is obtained and generated in the three-dimensional (3-D) space-time domain. Then, the 3-D full-field ultrasonic data is Fourier transformed and the ultrasonic frequency spectra are analyzed to determine the dominant frequency that is sensitive to the disbond defects. Continuous wavelet transform (CWT) based on fast Fourier transform (FFT) is implemented as a single-frequency bandpass filter to filter the full-field ultrasonic data in the 3-D space-time domain at the selected dominant frequency. The LUIS has shown the ability to detect the disbond with diameters of 11 mm and 23 mm which match to the pre-determined disbond sizes well. For future research, a robust signal processing algorithm and a model-based matched filter will be investigated to make the detection process autonomous and improve detectability

21 CFR 872.4850 - Ultrasonic scaler.

Science.gov (United States)

2010-04-01

... DEVICES DENTAL DEVICES Surgical Devices § 872.4850 Ultrasonic scaler. (a) Identification. An ultrasonic scaler is a device intended for use during dental cleaning and periodontal (gum) therapy to remove calculus deposits from teeth by application of an ultrasonic vibrating scaler tip to the teeth. (b...

Fabrication and inspection of stainless-steel-clad tubes for fast reactors

International Nuclear Information System (INIS)

Spriet, M.

1975-01-01

The production of cladding tubes requires a selection of the raw material, particular core taken during the cold and hot processes, special surface preparations, heat treatments, and intermediate control during the principal steps of fabrication. The inspection is made in two stages: acceptance tests at Vallourec (Eddy current and ultrasonic tests, metrology of internal and external diameter and thickness, metallography, analyses, tensile tests) and ultrasonic tests, metrology of external diameter and thickness, metallography, analyses, mechanical tests at high temperature) [fr

Ultrasonic Bat Deterrent Technology

Energy Technology Data Exchange (ETDEWEB)

Kinzie, Kevin; Rominger, Kathryn M.

2017-12-14

The project objective was to advance the development and testing of an Near commercial bat-deterrent system with a goal to increase the current GE deterrent system effectiveness to over 50% with broad species applicability. Additionally, the research supported by this program has provided insights into bat behavior and ultrasonic deterrent design that had not previously been explored. Prior research and development had demonstrated the effectiveness of a commercial-grade, air-powered, ultrasonic bat deterrent to be between 30-50% depending upon the species of bat. However, the previous research provided limited insight into the behavioral responses of bats in the presence of ultrasonic deterrent sound fields that could be utilized to improve effectiveness. A unique bat flight room was utilized to observe the behavioral characteristics of bats in the presence of ultrasonic sound fields. Behavioral testing in the bat flight facility demonstrated that ultrasonic sounds similar to those produced by the GE deterrent influenced the activities and behaviors, primarily those associated with foraging, of the species exposed. The study also indicated that continuous and pulsing ultrasonic signals had a similar effect on the bats, and confirmed that as ultrasonic sounds attenuate, their influence on the bats’ activities and behavior decreases. Ground testing at Wolf Ridge Wind, LLC and Shawnee National Forest assessed both continuous and pulsing deterrent signals emitted from the GE deterrent system and further enhanced the behavioral understanding of bats in the presence of the deterrent. With these data and observations, the existing 4-nozzle continuous, or steady, emission ultrasonic system was redesigned to a 6-nozzle system that could emit a pulsing signal covering a larger air space around a turbine. Twelve GE 1.6-100 turbines were outfitted with the deterrent system and a formal three-month field study was performed using daily carcass searches beneath the 12

Quality control of disinfection in ultrasonic baths

Energy Technology Data Exchange (ETDEWEB)

Schoene, H. [Technical University Dresden (Germany). Faculty of Mechanical Engineering; Jatzwauk, L. [University Hospital of the Technical University Dresden (Germany). Abt. Krankenhaushygiene

2002-07-01

Numerous investigations under laboratory conditions confirmed the microbicidal efficacy of ultrasonication. Morphological destruction was shown on bacteria and fungi as well as on different virus species. Ultrasonic treatment seems to increase the effect of different antibiotics and disinfectants. Reasons for this synergism are largely unknown and uninvestigated, but the active principle seems to bee the dispersing effect of ultrasonication in combination with the destruction of cell wall or cell membrane. Unfortunately no validation of test conditions exists for most of these investigations, regarding intensity and frequency of ultrasonic waves, temperature of liquid medium and measurement of cavitation which is an essential part of physical and chemical effects in ultrasonic baths. In contrast to most laboratory experiments sound density of ultrasound for treatment of medical instruments is below 1 W/cm{sup 2} because instruments will be destroyed under stronger ultrasonic conditions. The frequency is below 50 KHz. This paper describes bactericidal and fungicidal effects of low- intensity-ultrasonication and its synergistical support to chemical disinfection. (orig.)

The effects of corrosion conditions and cold work on the nodular corrosion of zircaloy-4

International Nuclear Information System (INIS)

You, Gil Sung

1992-02-01

The nodular corrosion of Zircaloy-4 was investigated on the effects of corrosion conditions and cold work. Variation of steam pressures, heat-up environments and prefilms were considered and cold work effects were also studied. The corrosion rate of Zircaloy-4 was dependent on pressure between 1 and 100 atm and it followed the cubic law as W=16.85 x P 0.31 for plate specimens and W=12.69 x P 0.27 for tube specimens, where W is weight gain (mg/dm 2 ) and P is the steam pressure (atm). The environment variation in autoclave during heat-up period did not affect the early stage of nodular corrosion. The prefilm, which was formed at 500 .deg. C under 1 atm steam for 4 hours, restrained the formation of the initial small nodules. The oxide film formed under 1 atm steam showed no difference of electrical resistivity from the oxides formed under 100 atm steam pressure. Cold work specimens showed the higher resistivity against nodular corrosion than as-received specimens. The corrosion resistance arising from cold work seems to be due to the texture changes by the cold work. The results showed that cold work can affect the later stage of uniform corrosion and the early stage of nodular corrosion, namely, the nodule initiation stage

Development and Application of an Ultrasonic Gas Flowmeter

International Nuclear Information System (INIS)

Hwang, Won Ho; Jeong, Hee Don; Park, Sang Gug; Jhang, Kyung Young

2002-01-01

This paper describes the development and the field application of the ultrasonic gas flowmeter for accurate measurement of the volumetric flow rate of gases in a harsh environmental conditions in iron and steel making company. This ultrasonic flowmeter is especially suited for measuring LDG, COG, BFG gases produced in iron and steel making process. This is a transit time type ultrasonic flowmeter. We have developed the transmitting and receiving algorithm of ultrasonic wave and the ultrasonic signal processing algorithm to develope a transit time type ultrasonic flowmeter. We have evaluated the performance of ultrasonic flowmeter by the calibration system with Venturi type standard flowmeter. We has confirmed its reliability by extensive field tests for a year in POSCO, iron and steel making company. Now we have developed the commercial model of ultrasonic flowmeter and applied to the POSCO gas line

Ultrasonic Tomography Imaging for Liquid-Gas Flow Measurement

Directory of Open Access Journals (Sweden)

Muhammad Jaysuman PUSPPANATHAN

2013-01-01

Full Text Available This research was carried out to measure two-phase liquid – gas flow regime by using a dual functionality ultrasonic transducer. Comparing to the common separated transmitter–receiver ultrasonic pairs transducer, the dual functionality ultrasonic transceiver is capable to produce the same measurable results hence further improvises and contributes to the hardware design improvement and system accuracy. Due to the disadvantages and the limitations of the separated ultrasonic transmitter–receiver pair, this paper presents a non-invasive ultrasonic tomography system using ultrasonic transceivers as an alternative approach. Implementation of ultrasonic transceivers, electronic measurement circuits, data acquisition system and suitable image reconstruction algorithms, the measurement of a liquid/gas flow was realized.

A New Servo Control Drive for Electro Discharge Texturing System Industrial Applications Using Ultrasonic Technology

Directory of Open Access Journals (Sweden)

M. Shafik

2013-07-01

Full Text Available This paper presents a new ultrasonic servo control drive for electro discharge texturing system industrial applications. The new drive is aiming to overcome the current teething issues of the existing electro discharge texturing system, servo control drive level of precision, processing stability, dynamic response and surface profile of the machined products. The new ultrasonic servo control drive consists of three main apparatuses, an ultrasonic motor, electronic driver and control unit. The ultrasonic motor consists of three main parts, the stator, rotor and sliding element. The motor design process, basic configuration, principles of motion, finite element analysis and experimental examination of the main characteristics is discussed in this paper. The electronic driver of the motor consists of two main stages which are the booster and piezoelectric amplifier. The experimental test and validation of the developed servo control drive in electro discharge texturing platform is also discussed and presented in this paper. The initial results showed that the ultrasonic servo control drive is able to provide: a bidirectional of motion, a resolution of <50μm and a dynamic response of <10msec. The electron microscopic micro examination into the textured samples showed that: a clear improvement in machining stability, products surface profile, a notable reduction in the processing time, arcing and short-circuiting teething phenomena.

Ultrasonic Stir Welding

Science.gov (United States)

Nabors, Sammy

2015-01-01

NASA Marshall Space Flight Center (MSFC) developed Ultrasonic Stir Welding (USW) to join large pieces of very high-strength metals such as titanium and Inconel. USW, a solid-state weld process, improves current thermal stir welding processes by adding high-power ultrasonic (HPU) energy at 20 kHz frequency. The addition of ultrasonic energy significantly reduces axial, frictional, and shear forces; increases travel rates; and reduces wear on the stir rod, which results in extended stir rod life. The USW process decouples the heating, stirring, and forging elements found in the friction stir welding process allowing for independent control of each process element and, ultimately, greater process control and repeatability. Because of the independent control of USW process elements, closed-loop temperature control can be integrated into the system so that a constant weld nugget temperature can be maintained during welding.

Multi-Stage Adaptive Noise Cancellation Technique for Synthetic Hard-α Inclusion

International Nuclear Information System (INIS)

Kim, Jae Joon

2003-01-01

Adaptive noise cancellation techniques are ideally suitable for reducing spatially varying noise due to the grain structure of material in ultrasonic nondestructive evaluation. Grain noises have an un-correlation property, while flaw echoes are correlated. Thus, adaptive filtering algorithms use the correlation properties of signals to enhance the signal-to-noise ratio (SNR) of the output signal. In this paper, a multi-stage adaptive noise cancellation (MANC) method using adaptive least mean square error (LMSE) filter for enhancing flaw detection in ultrasonic signals is proposed

Morphology of First Zoeal Stage of Four Genera of Alvinocaridid Shrimps from Hydrothermal Vents and Cold Seeps: Implications for Ecology, Larval Biology and Phylogeny.

Directory of Open Access Journals (Sweden)

Iván Hernández-Ávila

Full Text Available Alvinocaridid shrimps are endemic species inhabiting hydrothermal vents and/or cold seeps. Although indirect evidences (genetic and lipid markers suggest that their larval stages disperse widely and support large scale connectivity, larval life and mechanisms underlying dispersal are unknown in alvinocaridids. Here we provide for the first time detailed descriptions of the first larval stage (zoea I of four alvinocaridid species: Rimicaris exoculata and Mirocaris fortunata from the Mid-Atlantic Ridge, Alvinocaris muricola from the Congo Basin and Nautilocaris saintlaurentae from the Western Pacific. The larvae were obtained from onboard hatching of brooding females (either at atmospheric pressure or at habitat pressure in hyperbaric chambers and from the water column near adult habitats, sampled with plankton pumps or sediment traps. Major characteristics of the alvinocaridid larvae include undeveloped mandible and almost complete absence of setation in the inner margin of the mouth parts and maxillipeds. Although the larvae are very similar between the four species studied, some morphological features could be used for species identification. In addition, undeveloped mouthparts and the large amount of lipid reserves strongly support the occurrence of primary lecithotrophy in the early stage of alvinocaridids. Although lecithotrophy in decapod crustaceans is usually associated with abbreviated larval development, as a mechanism of larval retention, morphological and physiological evidences suggest the occurrence of an extended and lecithotrophic larval stage in the Alvinocarididae. These traits permit the colonization of widely dispersed and fragmented environments of hydrothermal vents and cold seeps. Distribution of larval traits along the phylogenetic reconstruction of the Alvinocarididae and related families suggest that lecithotrophy/planktotrophy and extended/abbreviated development have evolved independently along related families in all

Pitch-catch only ultrasonic fluid densitometer

Science.gov (United States)

Greenwood, M.S.; Harris, R.V.

1999-03-23

The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

Effect of cold work and aging on mechanical properties of a copper ...

Indian Academy of Sciences (India)

Unknown

Influence of cold working and aging on the mechanical properties of a ... toughness and ductility in various stages of cold work and aging may include high stress concentration at high ... copper is added to HSLA steels to cause precipitation.

Under sodium ultrasonic imaging system for PFBR

International Nuclear Information System (INIS)

Patankar, V.H.; Lalwani, S.K.; Agashe, A.A.

2014-01-01

Under Sodium UltraSonic Scanner (USUSS) has been developed to detect the growth and protrusion of fuel sub-assemblies of PFBR, submerged in liquid sodium by using the ultrasonic imaging technique during reactor shut-down when liquid sodium is at 180 ℃. The imaging is carried out prior to every Fuel handling operation. Electronics Division, BARC has designed and developed an 8-Channel Ultrasonic Imaging System (UIS) which consists of 4 downward viewing and 4 side viewing ultrasonic transducers alongwith pulser-receiver, signal processing electronics hardware and software. An automated mechanical scanner developed by IGCAR houses sodium immersible transducers to image the fuel sub assemblies. The system has been successfully tested with dummy protruding and grown FSAs, submerged under liquid sodium. Such ultrasonic imaging systems are not available to India from international market. The USUSS developed indigenously has all the features available in similar systems developed by other countries. After every imaging campaign, the mechanical scanner containing ultrasonic transducers is stored in the Argon filled storage-pit. Before every campaign of USUSS, it is necessary to check the healthiness of the sodium immersible and contaminated ultrasonic transducers, as the under-sodium scanner is decontaminated once in five years. For this purpose, a novel Non Contact Ultrasonic Inspection System (NCUIS) has been designed and developed by Electronics Division, BARC to check the functionality of the high-temperature and contaminated transducers of USUSS, using air-coupled ultrasonic technique. (author)

Effect of ultrasonic pre-treatment of thermomechanical pulp on hydrogen peroxide bleaching

Science.gov (United States)

Loranger, E.; Charles, A.; Daneault, C.

2012-12-01

Ultrasound pre-treatments of softwood TMP had been carried to evaluate its impact on the efficiency of hydrogen peroxide bleaching. The trials were performed after a factorial design of experiment using frequency, power and time as variables. The experiments were conducted in an ultrasonic bath and then bleached with hydrogen peroxide. Measurements such as brightness, L*A*B* color system coordinate, residual hydrogen peroxide and metal content were evaluated on bleached pulp. The results indicate that the effect of ultrasonic treatment on brightness was dependent on the ultrasound frequency used; the brightness increased slightly at 68 kHz and decreased at 40 and 170 kHz. These results were correlated to the ultrasound effect on the generation of transition metals (copper, iron and manganese) which are responsible for catalytic decomposition of hydrogen peroxide. The influence of metal interference was minimized by using a chelating agent such as diethylene triamine pentaacetic acid (DTPA). With the results obtained in this study we have identified a set of option conditions, e.g. 1000 W, 40 kHz, 1.5 % consistency and 0.2% addition of DTPA prior to the bleaching stage (after ultrasonic pre-treatment) who improve brightness by 2.5 %ISO.

WARM EXTENDED DENSE GAS AT THE HEART OF A COLD COLLAPSING DENSE CORE

International Nuclear Information System (INIS)

Shinnaga, Hiroko; Phillips, Thomas G.; Furuya, Ray S.; Kitamura, Yoshimi

2009-01-01

In order to investigate when and how the birth of a protostellar core occurs, we made survey observations of four well-studied dense cores in the Taurus molecular cloud using CO transitions in submillimeter bands. We report here the detection of unexpectedly warm (∼30-70 K), extended (radius of ∼2400 AU), dense (a few times 10 5 cm -3 ) gas at the heart of one of the dense cores, L1521F (MC27), within the cold dynamically collapsing components. We argue that the detected warm, extended, dense gas may originate from shock regions caused by collisions between the dynamically collapsing components and outflowing/rotating components within the dense core. We propose a new stage of star formation, 'warm-in-cold core stage (WICCS)', i.e., the cold collapsing envelope encases the warm extended dense gas at the center due to the formation of a protostellar core. WICCS would constitute a missing link in evolution between a cold quiescent starless core and a young protostar in class 0 stage that has a large-scale bipolar outflow.

Pulsed ultrasonic stir welding method

Science.gov (United States)

Ding, R. Jeffrey (Inventor)

2013-01-01

A method of performing ultrasonic stir welding uses a welding head assembly to include a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. In the method, the rod is rotated about its longitudinal axis during a welding operation. During the welding operation, a series of on-off ultrasonic pulses are applied to the rod such that they propagate parallel to the rod's longitudinal axis. At least a pulse rate associated with the on-off ultrasonic pulses is controlled.

Ultrasonic tests. Pt. 2

International Nuclear Information System (INIS)

Goebbels, K.

1980-01-01

After a basic treatment of ultrasonic wave propagation, of the state-of-the-art methods and the technical background in the preceeding part, advanced ultrasonic NDT techniques are presented here. The discussion of new development includes - manipulation systems, - automation of ultrasonic testing methods, documentation and evaluation. In the middle of this part the main problem areas will be discussed: - detection of defects (e.g. in coarse grained structures and welds), - classification of defects (e.g. discrimination between crack-like and volumetric faults), - sizing of defects. Research in the field of acoustical holography, development of probes and phased arrays, electromagnetic acoustic transducers and signal enhancement are the main contributing parts to the report. (orig./RW)

A comparative study on the property determination of metal matrix composites using ultrasonic and eddy current techniques

International Nuclear Information System (INIS)

Jeong, Hyun Jo

1997-01-01

Ultrasonic and eddy current methods were developed for the quantitative determination of material properties in particulate reinforced metal matrix composites. The proposed techniques employed measurements of ultrasonic velocity and eddy current conductivity, together with theoretical models which relate the effective anisotropic properties of the composites to their microstructures. The approach was used for a wide range of SiC particulate reinforced Al matrix(SiC p /Al) composites to estimate the particulate volume fractions of the composites. The SiC p volume fraction was calculated by coupling the measured velocity and conductivity with their corresponding model predictions. Both methods were shown to be reliable in determining the reinforcement volume fractions. However, the ultrasonic method was found to be better than the eddy current method, since the electrical conductivity was sensitive to the presence of intermetallic compounds formed during processing stage.

An optimum cold end configuration for helium liquefaction cycles

International Nuclear Information System (INIS)

Minta, M.; Smith, J.L.

1984-01-01

This chapter examines the effect of the non-ideal behavior of helium at low temperature on the performance of helium liquefaction cycles. The effect is isolated by means of a continuum model for the precooling stage. The cold end losses are due primarily to the composite effect of the non-ideality of helium at low temperatures and the heat exchanger losses, in addition to the component losses fixed by the expander/compressor efficiencies. Topics considered include continuously distributed full-pressure ratio expanders, continuously distributed full-flow expanders, the heat exchange effect (ideal gas working fluid, real gas working fluid), and cold end configuration. The cold end configuration minimizes the cycle cold end losses

Detailed simulation of ultrasonic inspections

International Nuclear Information System (INIS)

Chaplin, K.R.; Douglas, S.R.; Dunford, D.

1997-01-01

Simulation of ultrasonic inspection of engineering components have been performed at the Chalk River Laboratories of AECL for over 10 years. The computer model, called EWE for Elastic Wave Equations, solves the Elastic Wave Equations using a novel finite difference scheme. It simulates the propagation of an ultrasonic wave from the transducer to a flaw, the scatter of waves from the flaw, and measurement of signals at a receive transducer. Regions of different materials, water and steel for example, can be simulated. In addition, regions with slightly different material properties from the parent material can be investigated. The two major types of output are displays of the ultrasonic waves inside the component and the corresponding A-scans. EPRI and other organizations have used ultrasonic models for: defining acceptable ultrasonic inspection procedures, designing and evaluating inspection techniques, and for quantifying inspection reliability. The EWE model has been applied to the inspection of large pipes in a nuclear plant, gas pipeline welds and steam generator tubes. Most recent work has dealt with the ultrasonic inspection of pressure tubes in CANDU reactors. Pressure tube inspections can reliably detect and size defects; however, there are improvements that can be made. For example, knowing the sharpness of a flaw-tip is crucial for fitness for service assessments. Computer modelling of the ultrasonic inspection of flaws with different root radius has suggested inspection techniques that provide flaw tip radius information. A preliminary investigation of these methods has been made in the laboratory. The basis for the model will be reviewed at the presentation. Then the results of computer simulations will be displayed on a PC using an interactive program that analyzes simulated A-scans. This software tool gives inspection staff direct access to the results of computer simulations. (author)

The effects of ultrasonic solidification on aluminum

OpenAIRE

Đorđević Slavko 1

2003-01-01

The effect of ultrasound on characteristics of solidified aluminum was shown. An ultrasonic head and ultrasonic system for modification was designed and applied to the crystallizing aluminum melt. The ultrasonic generator allows power of 50-500 W, amplitude of oscillations 10-100 um.m and the operating frequency of 25 kHz. Ultrasonic modification was done by ultrasound introduced from above into the melt. Microstructure photographs show decreasing of the grain size more than five times.

The effects of ultrasonic solidification on aluminum

Directory of Open Access Journals (Sweden)

Đorđević Slavko 1

2003-01-01

Full Text Available The effect of ultrasound on characteristics of solidified aluminum was shown. An ultrasonic head and ultrasonic system for modification was designed and applied to the crystallizing aluminum melt. The ultrasonic generator allows power of 50-500 W, amplitude of oscillations 10-100 um.m and the operating frequency of 25 kHz. Ultrasonic modification was done by ultrasound introduced from above into the melt. Microstructure photographs show decreasing of the grain size more than five times.

Case studies in ultrasonic testing

International Nuclear Information System (INIS)

Prasad, V.; Satheesh, C.; Varde, P.V.

2015-01-01

Ultrasonic testing is widely used Non Destructive Testing (NDT) method and forms the essential part of In-service inspection programme of nuclear reactors. Main application of ultrasonic testing is for volumetric scanning of weld joints followed by thickness gauging of pipelines and pressure vessels. Research reactor Dhruva has completed the first In Service Inspection programme in which about 325 weld joints have been volumetrically scanned, in addition to thickness gauging of 300 meters of pipe lines of various sizes and about 24 nos of pressure vessels. Ultrasonic testing is also used for level measurements, distance measurements and cleaning and decontamination of tools. Two case studies are brought out in this paper in which ultrasonic testing is used successfully for identification of butterfly valve opening status and extent of choking in pipe lines in Dhruva reactor systems

Internal ultrasonic inspection of flexible pipe

Energy Technology Data Exchange (ETDEWEB)

Baltzersen, O. (IKU Petroleumsforskning A/S, Trondheim (Norway) Norwegian Inst. of Tech., Trondheim (Norway). Div. of Petroleum Engineering and Applied Geophysics); Waag, T.I. (IKU Petroleumsforskning A/S, Trondheim (Norway))

1993-10-01

Methods for internal ultrasonic inspection of flexible pipe have been investigated through experiments with a short sample of Coflexip pipe. Ultrasonic backscatter methods using normal and non-normal incidence have been used for qualitative high contrast ultrasonic imaging of the inner surface of the pipe. Analysis of the internal cross-section has been performed based on the use of a non-contact ultrasonic caliper, and processing procedures which enable calculation of, and compensation for, eccentricity of the tool in the pipe. The methods developed can be used to quantitatively estimate the thickness of the internal carcass, and perform high resolution topographic mapping of the inner surface. (Author)

Stresses in ultrasonically assisted bone cutting

International Nuclear Information System (INIS)

Alam, K; Mitrofanov, A V; Silberschmidt, V V; Baeker, M

2009-01-01

Bone cutting is a frequently used procedure in the orthopaedic surgery. Modern cutting techniques, such as ultrasonic assisted drilling, enable surgeons to perform precision operations in facial and spinal surgeries. Advanced understanding of the mechanics of bone cutting assisted by ultrasonic vibration is required to minimise bone fractures and to optimise the technique performance. The paper presents results of finite element simulations on ultrasonic and conventional bone cutting analysing the effects of ultrasonic vibration on cutting forces and stress distribution. The developed model is used to study the effects of cutting and vibration parameters (e.g. amplitude and frequency) on the stress distributions in the cutting region.

Estimation of residual stress in cold rolled iron-disks from strain measurements on the high resolution Fourier diffractometer

International Nuclear Information System (INIS)

Aksenov, V.L.; Balagurov, A.M.; Taran, Yu.V.

1995-01-01

The results of estimating residual stresses in cold rolled iron disks by measurements with the high resolution Fourier diffractometer (HRFD) at the IBR-2 pulsed reactor are presented. These measurements were made for calibration of magnetic and ultrasonic measurements carried out at the Fraunhofer-Institute for Nondestructive Testing in Saarbrucken (Germany). The tested objects were cold rolled steel disks of 2.5 mm thickness and diameter of about 500 mm used for forming small, gas pressure tanks. Neutron diffraction experiments were carried out at the scattering angle 2θ=+152 d eg with resolution Δd/d=1.5·10 -3 . The gauge volume was chosen according to the magnetic measurements lateral resolution 20x20 mm 2 . In the nearest future the neutron diffraction measurements with cold rolled iron disks at the scattering angle 2θ=±90 0 are planned. Also the texture analysis will be included in the Rietveld refinement procedure for more correct calculation of residual stress fields in the cold rolled materials. 8 refs., 10 figs., 1 tab

Fundamentals of ultrasonic phased arrays

CERN Document Server

Schmerr, Lester W

2014-01-01

This book describes in detail the physical and mathematical foundations of ultrasonic phased array measurements.?The book uses linear systems theory to develop a comprehensive model of the signals and images that can be formed with phased arrays. Engineers working in the field of ultrasonic nondestructive evaluation (NDE) will find in this approach a wealth of information on how to design, optimize and interpret ultrasonic inspections with phased arrays. The fundamentals and models described in the book will also be of significant interest to other fields, including the medical ultrasound and

New design of process for cold forging to improve multi-stage gas fitting

Directory of Open Access Journals (Sweden)

Han-Sung Huang

2016-04-01

Full Text Available This work develops a process that solves the problem of the formation of cracks inside forged gas fittings in the cold forging process that arises from poor forging process design. DEFORM-3D forming software was utilized, and macroscopic experiments with optical microscopy and scanning electron microscopy were conducted to investigate the processed structures and the distribution therein of metal flow lines, and to find the internal micro-cracks to determine whether the cold forging process is reasonable. Analytical results herein demonstrate that the stress and strain inside the gas fitting can be elucidated using metal forming software. Together with experimental results, they demonstrate that a concentration of stress damages the workpiece in the forming process. Moreover, as metal flow lines become narrower, the workpiece becomes more easily damaged. Consequently, the improved cold forging process that is described in this work should be utilized to reduce the occurrence of fine cracks and defects. Planning for proper die design and production, increasing the quality of products, and reducing the number of defective products promote industrial competitiveness.

Rotary ultrasonic machining of CFRP: A comparison with grinding.

Science.gov (United States)

Ning, F D; Cong, W L; Pei, Z J; Treadwell, C

2016-03-01

Carbon fiber reinforced plastic (CFRP) composites have been intensively used in various industries due to their superior properties. In aircraft and aerospace industry, a large number of holes are required to be drilled into CFRP components at final stage for aircraft assembling. There are two major types of methods for hole making of CFRP composites in industry, twist drilling and its derived multi-points machining methods, and grinding and its related methods. The first type of methods are commonly used in hole making of CFRP composites. However, in recent years, rotary ultrasonic machining (RUM), a hybrid machining process combining ultrasonic machining and grinding, has also been successfully used in drilling of CFRP composites. It has been shown that RUM is superior to twist drilling in many aspects. However, there are no reported investigations on comparisons between RUM and grinding in drilling of CFRP. In this paper, these two drilling methods are compared in five aspects, including cutting force, torque, surface roughness, hole diameter, and material removal rate. Copyright © 2015 Elsevier B.V. All rights reserved.

Method and apparatus to characterize ultrasonically reflective contrast agents

Science.gov (United States)

Pretlow, Robert A., III (Inventor)

1993-01-01

A method and apparatus for characterizing the time and frequency response of an ultrasonically reflective contrast agent is disclosed. An ultrasonically reflective contrast agent is injected, under constant pressure, into a fluid flowing through a pump flow circuit. The fluid and the ultrasonically reflective contrast agent are uniformly mixed in a mixing chamber, and the uniform mixture is passed through a contrast agent chamber. The contrast agent chamber is acoustically and axially interposed between an ultrasonic transducer chamber and an acoustic isolation chamber. A pulse of ultrasonic energy is transmitted into the contrast agent chamber from the ultrasonic transducer chamber. An echo waveform is received from the ultrasonically reflective contrast agent, and it is analyzed to determine the time and frequency response of the ultrasonically reflective contrast agent.

Factors of Nonlinear-ultrasonic Detection and Its Application to HR3C Fireside Corrosion

Directory of Open Access Journals (Sweden)

QIN Peng

2016-11-01

Full Text Available Based on the discussion of the factors influencing the nonlinear ultrasonic testing, the feasibility of nondestructive evaluation of HR3C fireside corrosion was investigated using nonlinear ultrasonic testing. The results show that the number of pulse string is no more than 2df/c and the installation of Hanning window is helpful to reduce the disturbance of the system, in addition, the rough surface of the sample has a significant impact on the nonlinear parameter β. The nonlinear coefficient demonstrates a phased growth trend as corrosion time prolongs. At the initial stage of corrosion(within 50h,there are small increments within 20% in the nonlinear coefficient, however,the nonlinear coefficient β is increased obviously with the duration time to 150h. Compared with un-corroded sample, the amplification in the sample corroded for 200h reaches to 260%. The monotonous varieties in nonlinear coefficient are consistent with the aggravation of corrosion damage,hence,it is feasible to nondestructively evaluate HR3C fireside corrosion by means of ultrasonic nonlinear testing.

Improvement of Ultrasonic Distance Measuring System

Directory of Open Access Journals (Sweden)

Jiang Yu

2018-01-01

Full Text Available This paper mainly introduces a kind of ultrasonic distance measuring system with AT89C51 single chip as the core component. The paper expounds the principle of ultrasonic sensor and ultrasonic ranging, hardware circuit and software program, and the results of experiment and analysis.The hardware circuit based on SCM, the software design adopts the advanced microcontroller programming language.The amplitude of the received signal and the time of ultrasonic propagation are regulated by closed loop control. [1,2]The double closed loop control technology for amplitude and time improves the measuring accuracy of the instrument. The experimental results show that greatly improves the measurement accuracy of the system.

Ultrasonic tests on materials with protective coatings

International Nuclear Information System (INIS)

Whaley, H.L.

1977-01-01

Protective coatings are applied to some nuclear components such as reactor vessels to inhibit surface corrosion. Since in-service ultrasonic inspection is required for such components, a study was performed to determine whether the use of protective coatings can affect ultrasonic tests. Two 2 in. thick steel plates were uniformly machined, sandblasted, and used as bases for two types of protective coatings. The type and thickness of the coating and the presence of contamination, such as fingerprints or mild oxidation under the paint, were the independent variables associated with the coating. Tests were run to determine the effects of the protective coatings on ultrasonic tests conducted on the steel plates. Significant variations in ultrasonic test sensitivity occurred as a function of the type and thickness of protective coating, couplant (material that conducts the ultrasound from the transducer into the test part, normally water or some type of oil), transducer wear plate, and ultrasonic test frequency. Ultrasonic tests can be strongly affected by a protective coating on the component to be inspected. As compared to the test sensitivity for an uncoated reference sample, the sensitivity may be dramatically shifted up or down on the coated surface. In certain coating thickness ranges, the sensitivity can fluctuate widely with small changes in coating thickness. If a coating is chosen properly, however, components with protective coatings can be tested ultrasonically with valid results. These results are for the case of ultrasonic input on the coated surface. It is not expected that an ultrasonic test conducted from the front surface would be appreciably affected by a coating on the rear surface

Ultrasonic propulsion of kidney stones.

Science.gov (United States)

May, Philip C; Bailey, Michael R; Harper, Jonathan D

2016-05-01

Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments. Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

Study on electrical impedance matching for broadband ultrasonic transducer

Energy Technology Data Exchange (ETDEWEB)

Kim, Geon Woo [University of Science and Technology, Daejeon (Korea, Republic of); Kim, Ki Bok [Korea Research Institute of Standards and Science, Center for Safety Measurement, Daejeon (Korea, Republic of); Baek, Kwang Sae [Elache Co., Busan (Korea, Republic of)

2017-02-15

Ultrasonic transducers with high resolution and resonant frequency are required to detect small defects (less than hundreds of μm) by ultrasonic testing. The resonance frequency and resolution of an ultrasonic transducer are closely related to the thickness of piezo-electric materials, backing materials, and the electric impedance matching technique. Among these factors, electrical impedance matching plays an important role because it can reduce the loss and reflection of ultrasonic energy differences in electrical impedance between an ultrasonic transducer and an ultrasonic defects detecting system. An LC matching circuit is the most frequently used electric matching method. It is necessary for the electrical impedance of an ultrasonic transducer to correspond to approximately 50 Ω to compensate the difference in electrical impedance between both connections. In this study, a 15 MHz immersion ultrasonic transducer was fabricated and an LC electrical impedance circuit was applied to that for having broad-band frequency characteristic.

Ultrasonic inspection of austenitic welds

International Nuclear Information System (INIS)

Baikie, B.L.; Wagg, A.R.; Whittle, M.J.; Yapp, D.

1976-01-01

Optical and X-ray metallography combined with ultrasonic testing by compression waves was used for inspection of stainless steel weld metal produced by three different welding techniques. X-ray diffraction showed that each weld possessed a characteristic fibre textured structure which was shown by optical microscopy to be parallel to columnar grain boundaries. Metallographic evidence suggested that the development of fibre texture is due to the mechanism of competitive growth. From observations made as a result of optical metallographic examination the orientation of the fibre axis could be predicted if the weld geometry and welding procedure were known. Ultrasonic velocity and attenuation measurements as a continuous function of grain orientation, made on cylinders machined from weld samples, showed that attenuation was strongly orientation dependent. It was concluded that the sensitivity of ultrasonic inspection to small defects is unlikely to be as high for austenitic welds as for ferritic even when transmission is improved by modifying the welding procedure to improve the ultrasonic transmission. (U.K.)

Rail inspection using noncontact laser ultrasonics

International Nuclear Information System (INIS)

Kim, Nak Hyeon; Sohn, Hoon; Han, Soon Woo

2012-01-01

In this study, a noncontact laser ultrasonic system is proposed for rail defect detection. An Nd Yag pulse laser is used for generation of ultrasonic waves, and the corresponding ultrasonic responses are measured by a laser Doppler vibrometer. For the detection of rail surface damages, the shape of the excitation laser beam is transformed into a line. On the other hand, a point source laser beam is used for the inspection of defects inside a rail head. Then, the interactions of propagating ultrasonic waves with defects are examined using actual rail specimens. Amplitude attenuation was mainly observed for a surface crack, and reflections were most noticeable from an internal damage. Finally, opportunities and challenges associated with real time rail inspection from a high speed train are discussed

Ultrasonic characterization of yogurt fermentation process

OpenAIRE

IZBAIM , DRIS; FAIZ , BOUAZZA; MOUDDEN , ALI; MALAININE , MOHAMED; ABOUDAOUD , Idriss

2012-01-01

International audience; The objective of this work is to characterize the fermentation of yogurt based on an ultrasonic technique. Conventionally, the acidity of the yogurt is measured by a pH meter to determine the progress of fermentation. However, the pH meter should be cleaned and calibrated for each measurement and, therefore, this method is not practical. In this regard, ultrasonic techniques are fast, non-invasive and inexpensive. The measurement of ultrasonic parameters such as amplit...

Ultrasonic Characterization of Superhard Material: Osmium Diboride

International Nuclear Information System (INIS)

Yadawa, P K

2012-01-01

Higher order elastic constants have been calculated in hexagonal structured superhard material OsB 2 at room temperature following the interaction potential model. The temperature variation of the ultrasonic velocities is evaluated along different angles with unique axis of the crystal using the second order elastic constants. The ultrasonic velocity decreases with the temperature along particular orientation with the unique axis. Temperature variation of the thermal relaxation time and Debye average velocities are also calculated along the same orientation. The temperature dependency of the ultrasonic properties is discussed in correlation with elastic, thermal and electrical properties. It has been found that the thermal conductivity is the main contributor to the behaviour of ultrasonic attenuation as a function of temperature and the responsible cause of attenuation is phonon-phonon interaction. The mechanical properties of OsB 2 at low temperature are better than at high temperature, because at low temperature it has low ultrasonic velocity and ultrasonic attenuation. Superhard material OsB 2 has many industrial applications, such as abrasives, cutting tools and hard coatings.

Studies on Section XI ultrasonic repeatability

International Nuclear Information System (INIS)

Jamison, T.D.; McDearman, W.R.

1981-05-01

A block representative of a nuclear component has been welded containing intentional defects. Acoustic emission data taken during the welding correlate well with ultrasonic data. Repetitive ultrasonic examinations have been performed by skilled operators using a procedure based on that desribed in ASME Section XI. These examinations were performed by different examination teams using different ultrasonic equipment in such a manner that the effects on the repeatability of the ultrasonic test method caused by the operator and by the use of different equipment could be estimated. It was tentatively concluded that when considering a large number of inspections: (1) there is no significant difference in indication sizing between operators, and (2) there is a significant difference in amplitude and defect sizing when instruments having different, Code acceptable operating characteristics are used. It was determined that the Section XI sizing parameters follow a bivariate normal distribution. Data derived from ultrasonically and physically sizing indications in nuclear components during farication show that the Section XI technique tends to overestimate the size of the reflectors

Uncertainty estimation of ultrasonic thickness measurement

International Nuclear Information System (INIS)

Yassir Yassen, Abdul Razak Daud; Mohammad Pauzi Ismail; Abdul Aziz Jemain

2009-01-01

The most important factor that should be taken into consideration when selecting ultrasonic thickness measurement technique is its reliability. Only when the uncertainty of a measurement results is known, it may be judged if the result is adequate for intended purpose. The objective of this study is to model the ultrasonic thickness measurement function, to identify the most contributing input uncertainty components, and to estimate the uncertainty of the ultrasonic thickness measurement results. We assumed that there are five error sources significantly contribute to the final error, these sources are calibration velocity, transit time, zero offset, measurement repeatability and resolution, by applying the propagation of uncertainty law to the model function, a combined uncertainty of the ultrasonic thickness measurement was obtained. In this study the modeling function of ultrasonic thickness measurement was derived. By using this model the estimation of the uncertainty of the final output result was found to be reliable. It was also found that the most contributing input uncertainty components are calibration velocity, transit time linearity and zero offset. (author)

Experimental investigation of ultrasonic velocity anisotropy in ...

Indian Academy of Sciences (India)

Permanent link: https://www.ias.ac.in/article/fulltext/pram/077/02/0345-0355. Keywords. Magnetic fluids; ultrasonic wave; sound velocity; anisotropy. Abstract. Magnetic field-induced dispersion of ultrasonic velocity in a Mn0.7Zn0.3Fe2O4 fluid (applied magnetic field is perpendicular to the ultrasonic propagation vector) is ...

Microstructure and texture evolution of ultra-thin grain-oriented silicon steel sheet fabricated using strip casting and three-stage cold rolling method

Energy Technology Data Exchange (ETDEWEB)

Song, Hong-Yu; Liu, Hai-Tao, E-mail: liuht@ral.neu.edu.cn; Wang, Yin-Ping; Wang, Guo-Dong

2017-03-15

A 0.1 mm-thick grain-oriented silicon steel sheet was successfully produced using strip casting and three-stage cold rolling method. The microstructure, texture and inhibitor evolution during the processing was briefly analyzed. It was found that Goss texture was absent in the hot rolled sheet because of the lack of shear deformation. After normalizing, a large number of dispersed MnS precipitates with the size range of 15–90 nm were produced. During first cold rolling, dense shear bands were generated in the deformed ferrite grains, resulting in the intense Goss texture after first intermediate annealing. The microstructure was further refined and homogenized during the subsequent cold rolling and annealing processes. After primary recrystallization annealing, a homogeneous microstructure consisting of fine and equiaxed grains was produced while the associated texture was characterized by a strong γ-fiber texture. Finally, a complete secondary recrystallization microstructure consisting of entirely large Goss grains was produced. The magnetic induction B{sub 8} and iron loss P{sub 10/400} was 1.79 T and 6.9 W/kg, respectively. - Highlights: • Ultra-thin grain-oriented silicon steel was produced by strip casting process. • Microstructure, texture and inhibitor evolution was briefly investigated. • Goss texture was absent in primary recrystallization annealed sheet. • MnS precipitates with a size range of 15–90 nm formed after normalizing. • A complete secondary recrystallization microstructure was produced.

Ultrasonic Waveguide Sensor with a Layer-Structured Plate

International Nuclear Information System (INIS)

Joo, Young Sang; Bae, Jin Ho; Kim, Jong Bum

2010-01-01

In-vessel structures of a sodium-cooled fast reactor (SFR) are submerged in opaque liquid sodium in reactor vessel. The ultrasonic inspection techniques should be applied for observing the in-vessel structures under hot liquid sodium. Ultrasonic sensors such as immersion sensors and rod-type waveguide sensors had developed in order to apply under-sodium viewing of the in-vessel structures of SFR. Recently the novel plate-type ultrasonic waveguide sensor has been developed for the versatile application of under-sodium viewing in SFR. In the previous studies, the Ultrasonic waveguide sensor module had been designed and manufactured. And the feasibility study of the ultrasonic waveguide sensor has been performed. To Improve the performance of the ultrasonic waveguide sensor module in the under-sodium application, the dispersion effect due to the 10 m long distance propagation of the A 0 -mode Lamb wave should be minimized and the longitudinal leaky wave in a liquid sodium should be generated within the range of the effective radiation angle. In this study, a new concept of ultrasonic waveguide sensor with a layered-structured plate is suggested for the non-dispersive propagation of A 0 -mode Lamb wave in an ultrasonic waveguide sensor and the effective generation of leaky wave in a liquid sodium

21 CFR 882.1925 - Ultrasonic scanner calibration test block.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic scanner calibration test block. 882... Ultrasonic scanner calibration test block. (a) Identification. An ultrasonic scanner calibration test block is a block of material with known properties used to calibrate ultrasonic scanning devices (e.g., the...

Ultrasonic attenuation in superconducting zinc

International Nuclear Information System (INIS)

Auluck, S.

1978-01-01

The differences in the Zn ultrasonic attenuation data of different workers are analyzed. The superconducting energy gaps deduced from our analysis of the ultrasonic-attenuation data of Cleavelin and Marshall are consistent with the gaps deduced from the knowledge of the Fermi surface and the electron-phonon mass enhancement factor

Results of molten salt panel and component experiments for solar central receivers: Cold fill, freeze/thaw, thermal cycling and shock, and instrumentation tests

Energy Technology Data Exchange (ETDEWEB)

Pacheco, J.E.; Ralph, M.E.; Chavez, J.M.; Dunkin, S.R.; Rush, E.E.; Ghanbari, C.M.; Matthews, M.W.

1995-01-01

Experiments have been conducted with a molten salt loop at Sandia National Laboratories in Albuquerque, NM to resolve issues associated with the operation of the 10MW{sub e} Solar Two Central Receiver Power Plant located near Barstow, CA. The salt loop contained two receiver panels, components such as flanges and a check valve, vortex shedding and ultrasonic flow meters, and an impedance pressure transducer. Tests were conducted on procedures for filling and thawing a panel, and assessing components and instrumentation in a molten salt environment. Four categories of experiments were conducted: (1) cold filling procedures, (2) freeze/thaw procedures, (3) component tests, and (4) instrumentation tests. Cold-panel and -piping fill experiments are described, in which the panels and piping were preheated to temperatures below the salt freezing point prior to initiating flow, to determine the feasibility of cold filling the receiver and piping. The transient thermal response was measured, and heat transfer coefficients and transient stresses were calculated from the data. Freeze/thaw experiments were conducted with the panels, in which the salt was intentionally allowed to freeze in the receiver tubes, then thawed with heliostat beams. Slow thermal cycling tests were conducted to measure both how well various designs of flanges (e.g., tapered flanges or clamp type flanges) hold a seal under thermal conditions typical of nightly shut down, and the practicality of using these flanges on high maintenance components. In addition, the flanges were thermally shocked to simulate cold starting the system. Instrumentation such as vortex shedding and ultrasonic flow meters were tested alongside each other, and compared with flow measurements from calibration tanks in the flow loop.

Ultrasonic scanner for stainless steel weld inspections. [LMFBR

Energy Technology Data Exchange (ETDEWEB)

Kupperman, D. S.; Reimann, K. J.

1978-09-01

The large grain size and anisotropic nature of stainless steel weld metal make conventional ultrasonic testing very difficult. A technique is evaluated for minimizing the coherent ultrasonic noise in stainless steel weld metal. The method involves digitizing conventional ''A-scan'' traces and averaging them with a minicomputer. Results are presented for an ultrasonic scanner which interrogates a small volume of the weld metal while averaging the coherent ultrasonic noise.

Ultrasonic assisted hot metal powder compaction.

Science.gov (United States)

Abedini, Rezvan; Abdullah, Amir; Alizadeh, Yunes

2017-09-01

Hot pressing of metal powders is used in production of parts with similar properties to wrought materials. During hot pressing processes, particle rearrangement, plastic deformation, creep, and diffusion are of the most effective powder densification mechanisms. Applying ultrasonic vibration is thought to result in great rates of densification and therefore higher efficiency of the process is expected. This paper deals with the effects of power ultrasonic on the densification of AA1100 aluminum powder under constant applied stress. The effects of particle size and process temperature on the densification behavior are discussed. The results show that applying ultrasonic vibration leads to an improved homogeneity and a higher relative density. Also, it is found that the effect of ultrasonic vibration is greater for finer particles. Copyright © 2016 Elsevier B.V. All rights reserved.

Ultrasonic nondestructive materials characterization

Science.gov (United States)

Green, R. E., Jr.

1986-01-01

A brief review of ultrasonic wave propagation in solid materials is presented with consideration of the altered behavior in anisotropic and nonlinear elastic materials in comparison with isotropic and linear elastic materials. Some experimental results are described in which ultrasonic velocity and attenuation measurements give insight into materials microstructure and associated mechanical properties. Recent developments with laser beam non-contact generation and detection of ultrasound are presented. The results of several years of experimental measurements using high-power ultrasound are discussed, which provide substantial evidence of the inability of presently accepted theories to fully explain the interaction of ultrasound with solid materials. Finally, a special synchrotron X-ray topographic system is described which affords the possibility of observing direct interaction of ultrasonic waves with the microstructural features of real crystalline solid materials for the first time.

Ultrasonic colour Doppler imaging

DEFF Research Database (Denmark)

Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

2011-01-01

Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

Study on Effect of Ultrasonic Vibration on Grinding Force and Surface Quality in Ultrasonic Assisted Micro End Grinding of Silica Glass

Directory of Open Access Journals (Sweden)

Zhang Jianhua

2014-01-01

Full Text Available Ultrasonic vibration assisted micro end grinding (UAMEG is a promising processing method for micro parts made of hard and brittle materials. First, the influence of ultrasonic assistance on the mechanism of this processing technology is theoretically analyzed. Then, in order to reveal the effects of ultrasonic vibration and grinding parameters on grinding forces and surface quality, contrast grinding tests of silica glass with and without ultrasonic assistance using micro radial electroplated diamond wheel are conducted. The grinding forces are measured using a three-component dynamometer. The surface characteristics are detected using the scanning electron microscope. The experiment results demonstrate that grinding forces are significantly reduced by introducing ultrasonic vibration into conventional micro end grinding (CMEG of silica glass; ultrasonic assistance causes inhibiting effect on variation percentages of tangential grinding force with grinding parameters; ductile machining is easier to be achieved and surface quality is obviously improved due to ultrasonic assistance in UAMEG. Therefore, larger grinding depth and feed rate adopted in UAMEG can lead to the improvement of removal rate and machining efficiency compared with CMEG.

Lumber defect detection by ultrasonics

Science.gov (United States)

K. A. McDonald

1978-01-01

Ultrasonics, the technology of high-frequency sound, has been developed as a viable means for locating most defects In lumber for use in digital form in decision-making computers. Ultrasonics has the potential for locating surface and internal defects in lumber of all species, green or dry, and rough sawn or surfaced.

Work Hardening Behavior of 1020 Steel During Cold-Beating Simulation

Science.gov (United States)

CUI, Fengkui; LING, Yuanfei; XUE, Jinxue; LIU, Jia; LIU, Yuhui; LI, Yan

2017-03-01

The present research of cold-beating formation mainly focused on roller design and manufacture, kinematics, constitutive relation, metal flow law, thermo-mechanical coupling, surface micro-topography and microstructure evolution. However, the research on surface quality and performance of workpieces in the process of cold-beating is rare. Cold-beating simulation experiment of 1020 steel is conducted at room temperature and strain rates ranging from 2000 to 4000 s-1 base on the law of plastic forming. According to the experimental data, the model of strain hardening of 1020 steel is established, Scanning Electron Microscopy(SEM) is conducted, the mechanism of the work hardening of 1020 steel is clarified by analyzing microstructure variation of 1020 steel. It is found that the strain rate hardening effect of 1020 steel is stronger than the softening effect induced by increasing temperatures, the process of simulation cold-beating cause the grain shape of 1020 steel significant change and microstructure elongate significantly to form a fibrous tissue parallel to the direction of deformation, the higher strain rate, the more obvious grain refinement and the more hardening effect. Additionally, the change law of the work hardening rate is investigated, the relationship between dislocation density and strain, the relationship between work hardening rate and dislocation density is obtained. Results show that the change trend of the work hardening rate of 1020 steel is divided into two stages, the work hardening rate decreases dramatically in the first stage and slowly decreases in the second stage, finally tending toward zero. Dislocation density increases with increasing strain and strain rate, work hardening rate decreases with increasing dislocation density. The research results provide the basis for solving the problem of improving the surface quality and performance of workpieces under cold-beating formation of 1020 steel.

Detection of cold pain, cold allodynia and cold hyperalgesia in freely behaving rats

Directory of Open Access Journals (Sweden)

Woolf Clifford J

2005-12-01

Full Text Available Abstract Background Pain is elicited by cold, and a major feature of many neuropathic pain states is that normally innocuous cool stimuli begin to produce pain (cold allodynia. To expand our understanding of cold induced pain states we have studied cold pain behaviors over a range of temperatures in several animal models of chronic pain. Results We demonstrate that a Peltier-cooled cold plate with ± 1°C sensitivity enables quantitative measurement of a detection withdrawal response to cold stimuli in unrestrained rats. In naïve rats the threshold for eliciting cold pain behavior is 5°C. The withdrawal threshold for cold allodynia is 15°C in both the spared nerve injury and spinal nerve ligation models of neuropathic pain. Cold hyperalgesia is present in the spared nerve injury model animals, manifesting as a reduced latency of withdrawal response threshold at temperatures that elicit cold pain in naïve rats. We also show that following the peripheral inflammation produced by intraplantar injection of complete Freund's adjuvant, a hypersensitivity to cold occurs. Conclusion The peltier-cooled provides an effective means of assaying cold sensitivity in unrestrained rats. Behavioral testing of cold allodynia, hyperalgesia and pain will greatly facilitate the study of the neurobiological mechanisms involved in cold/cool sensations and enable measurement of the efficacy of pharmacological treatments to reduce these symptoms.

Computer simulation of ultrasonic testing for aerospace vehicle

Energy Technology Data Exchange (ETDEWEB)

Yamawaki, H [National Institute for Materials Science, 1-2-1, Sengen, 305-0047 Tsukuba (Japan); Moriya, S; Masuoka, T [Japan Aerospace Exploration Agency, 1 Koganesawa, Kimigawa, 981-1525 Kakuda (Japan); Takatsubo, J, E-mail: yamawaki.hisashi@nims.go.jp [Advanced Industrial Science and Technology, AIST Tsukuba Central 2, 1-1-1 Umezono, 305-8568 Tsukuba (Japan)

2011-01-01

Non-destructive testing techniques are developed to secure reliability of aerospace vehicles used repetitively. In the case of cracks caused by thermal stress on walls in combustion chambers of liquid-fuel rockets, it is examined by ultrasonic waves visualization technique developed in AIST. The technique is composed with non-contact ultrasonic generation by pulsed-laser scanning, piezoelectric transducer for the ultrasonic detection, and image reconstruction processing. It enables detection of defects by visualization of ultrasonic waves scattered by the defects. In NIMS, the condition of the detection by the visualization is investigated using computer simulation for ultrasonic propagation that has capability of fast 3-D calculation. The simulation technique is based on finite-difference method and two-step elastic wave equations. It is reported about the investigation by the calculation, and shows availability of the simulation for the ultrasonic testing technique of the wall cracks.

Fundamentals and applications of ultrasonic waves

CERN Document Server

Cheeke, J David N

2002-01-01

Ultrasonics. A subject with applications across all the basic sciences, engineering, medicine, and oceanography, yet even the broader topic of acoustics is now rarely offered at undergraduate levels. Ultrasonics is addressed primarily at the doctoral level, and texts appropriate for beginning graduate students or newcomers to the field are virtually nonexistent.Fundamentals and Applications of Ultrasonic Waves fills that void. Designed specifically for senior undergraduates, beginning graduate students, and those just entering the field, it begins with the fundamentals, but goes well beyond th

Ultrasonic flow measurements for irrigation process monitoring

Science.gov (United States)

Ziani, Elmostafa; Bennouna, Mustapha; Boissier, Raymond

2004-02-01

This paper presents the state of the art of the general principle of liquid flow measurements by ultrasonic method, and problems of flow measurements. We present an ultrasonic flowmeter designed according to smart sensors concept, for the measurement of irrigation water flowing through pipelines or open channels, using the ultrasonic transit time approach. The new flowmeter works on the principle of measuring time delay differences between sound pulses transmitted upstream and downstream in the flowing liquid. The speed of sound in the flowing medium is eliminated as a variable because the flowrate calculations are based on the reciprocals of the transmission times. The transit time difference is digitally measured by means of a suitable, microprocessor controlled logic. This type of ultrasonic flowmeter will be widely used in industry and water management, it is well studied in this work, followed by some experimental results. For pressurized channels, we use one pair of ultrasonic transducer arranged in proper positions and directions of the pipe, in this case, to determine the liquid velocity, a real time on-line analysis taking account the geometries of the hydraulic system, is applied to the obtained ultrasonic data. In the open channels, we use a single or two pairs of ultrasonic emitter-receiver according to the desired performances. Finally, the goals of this work consist in integrating the smart sensor into irrigation systems monitoring in order to evaluate potential advantages and demonstrate their performance, on the other hand, to understand and use ultrasonic approach for determining flow characteristics and improving flow measurements by reducing errors caused by disturbances of the flow profiles.

The study on a gas-coupled two-stage stirling-type pulse tube cryocooler

Science.gov (United States)

Wu, X. L.; Chen, L. B.; Zhu, X. S.; Pan, C. Z.; Guo, J.; Wang, J. J.; Zhou, Y.

2017-12-01

A two-stage gas-coupled Stirling-type pulse tube cryocooler (SPTC) driven by a linear dual-opposed compressor has been designed, manufactured and tested. Both of the stages adopted coaxial structure for compactness. The effect of a cold double-inlet at the second stage on the cooling performance was investigated. The test results show that the cold double-inlet will help to achieve a lower cooling temperature, but it is not conducive to achieving a higher cooling capacity. At present, without the cold double-inlet, the second stage has achieved a no-load temperature of 11.28 K and a cooling capacity of 620 mW/20 K with an input electric power of 450 W. With the cold double-inlet, the no-load temperature is lowered to 9.4 K, but the cooling capacity is reduced to 400 mW/20 K. The structure of the developed cryocooler and the influences of charge pressure, operating frequency and hot end temperature will also be introduced in this paper.

Ultrasonic sectional imaging for crack identification. Part 1. Confirmation test of essential factors for ultrasonic imaging

International Nuclear Information System (INIS)

Sasahara, Toshihiko

2008-01-01

Since the first reports of inter-granular stress corrosion crack (IGSCC) in boiling water reactor (BWR) pipe in the 1970s, nuclear power industry has focused considerable attention on service induced crack detection and sizing using ultrasonic examination. In recent years, phased array systems, those reconstruct high quality flaw images at real time are getting to apply for crack detection and sizing. But because the price of phased array systems are expensive for inspection vendors, field application of phased array systems are limited and reliable ultrasonic imaging systems with reasonable price are expected. This paper will discuss cost effective ultrasonic equipment with sectional image (B-scan) presentation as the simplified imaging system for assisting ultrasonic examination personnel. To develop the simplified B-scan imaging system, the frequency characteristics of IGSCC echoes and neighboring geometry echoes such as base-metal to weld interface and inner surface of a pipe are studied. The experimental study confirmed the reflectors have different frequency characteristics and 2MHz is suitable to visualize IGSCC and 5MHz and higher frequency are suitable to reconstruct geometry images. The other study is the amplifier selection for the imaging system. To reconstruct images of IGSCC and geometry echoes, the ultrasonic imaging instrument with linear amplifier has to adjust gain setting to the target. On the other hand, the ultrasonic imaging instrument with logarithmic amplifier can collect and display wider dynamic range on a screen and this wider dynamic range are effective to visualize IGSCC and geometry echoes on a B-scan presentation at a time. (author)

Resonant difference-frequency atomic force ultrasonic microscope

Science.gov (United States)

Cantrell, John H. (Inventor); Cantrell, Sean A. (Inventor)

2010-01-01

A scanning probe microscope and methodology called resonant difference-frequency atomic force ultrasonic microscopy (RDF-AFUM), employs an ultrasonic wave launched from the bottom of a sample while the cantilever of an atomic force microscope, driven at a frequency differing from the ultrasonic frequency by one of the contact resonance frequencies of the cantilever, engages the sample top surface. The nonlinear mixing of the oscillating cantilever and the ultrasonic wave in the region defined by the cantilever tip-sample surface interaction force generates difference-frequency oscillations at the cantilever contact resonance. The resonance-enhanced difference-frequency signals are used to create images of nanoscale near-surface and subsurface features.

Recent progress in online ultrasonic process monitoring

Science.gov (United States)

Wen, Szu-Sheng L.; Chen, Tzu-Fang; Ramos-Franca, Demartonne; Nguyen, Ky T.; Jen, Cheng-Kuei; Ihara, Ikuo; Derdouri, A.; Garcia-Rejon, Andres

1998-03-01

On-line ultrasonic monitoring of polymer co-extrusion and gas-assisted injection molding are presented. During the co- extrusion of high density polyethylene and Santoprene ultrasonic sensors consisting of piezoelectric transducers and clad ultrasonic buffer rods are used to detect the interface between these two polymers and the stability of the extrusion. The same ultrasonic sensor also measures the surface temperature of the extruded polymer. The results indicate that temperature measurements using ultrasound have a faster response time than those obtained by conventional thermocouple. In gas-assisted injection molding the polymer and gas flow front positions are monitored simultaneously. This information may be used to control the plunger movement.

Auto-positioning ultrasonic transducer system

Science.gov (United States)

Buchanan, Randy K. (Inventor)

2010-01-01

An ultrasonic transducer apparatus and process for determining the optimal transducer position for flow measurement along a conduit outer surface. The apparatus includes a transmitting transducer for transmitting an ultrasonic signal, said transducer affixed to a conduit outer surface; a guide rail attached to a receiving transducer for guiding movement of a receiving transducer along the conduit outer surface, wherein the receiving transducer receives an ultrasonic signal from the transmitting transducer and sends a signal to a data acquisition system; and a motor for moving the receiving transducer along the guide rail, wherein the motor is controlled by a controller. The method includes affixing a transmitting transducer to an outer surface of a conduit; moving a receiving transducer on the conduit outer surface, wherein the receiving transducer is moved along a guide rail by a motor; transmitting an ultrasonic signal from the transmitting transducer that is received by the receiving transducer; communicating the signal received by the receiving transducer to a data acquisition and control system; and repeating the moving, transmitting, and communicating along a length of the conduit.

Hand Gesture Recognition Using Ultrasonic Waves

KAUST Repository

AlSharif, Mohammed Hussain

2016-04-01

Gesturing is a natural way of communication between people and is used in our everyday conversations. Hand gesture recognition systems are used in many applications in a wide variety of fields, such as mobile phone applications, smart TVs, video gaming, etc. With the advances in human-computer interaction technology, gesture recognition is becoming an active research area. There are two types of devices to detect gestures; contact based devices and contactless devices. Using ultrasonic waves for determining gestures is one of the ways that is employed in contactless devices. Hand gesture recognition utilizing ultrasonic waves will be the focus of this thesis work. This thesis presents a new method for detecting and classifying a predefined set of hand gestures using a single ultrasonic transmitter and a single ultrasonic receiver. This method uses a linear frequency modulated ultrasonic signal. The ultrasonic signal is designed to meet the project requirements such as the update rate, the range of detection, etc. Also, it needs to overcome hardware limitations such as the limited output power, transmitter, and receiver bandwidth, etc. The method can be adapted to other hardware setups. Gestures are identified based on two main features; range estimation of the moving hand and received signal strength (RSS). These two factors are estimated using two simple methods; channel impulse response (CIR) and cross correlation (CC) of the reflected ultrasonic signal from the gesturing hand. A customized simple hardware setup was used to classify a set of hand gestures with high accuracy. The detection and classification were done using methods of low computational cost. This makes the proposed method to have a great potential for the implementation in many devices including laptops and mobile phones. The predefined set of gestures can be used for many control applications.

Ultrasonic wave propagation in powders

Science.gov (United States)

Al-Lashi, R. S.; Povey, M. J. W.; Watson, N. J.

2018-05-01

Powder clumps (cakes) has a significant effect on the flowability and stability of powders. Powder caking is mainly caused by moisture migration due to wetting and environmental (temperature and humidity) changes. The process of moisture migration caking involves creating liquid bridges between the particles during condensation which subsequently harden to form solid bridges. Therefore, an effective and reliable technique is required to quantitatively and non-invasively monitor caking kinetics and effective stiffness. This paper describes two ultrasonic instruments (ultrasonic velocity pulse and airborne ultrasound systems) that have been used to monitor the caking phenomenon. Also, it discusses the relationship between the ultrasonic velocity and attenuation measurements and tracking caking kinetics and the effective stiffness of powders.

Feasibility of ultrasonic and eddy current methods for measurement of residual stress in shot peened metals

International Nuclear Information System (INIS)

Lavrentyev, Anton I.; Stucky, Paul A.; Veronesi, William A.

2000-01-01

Shot peening is a well-known method for extending the fatigue life of metal components by introducing compressive residual stresses near their surfaces. The capability to nondestructively evaluate the near surface residual stress would greatly aid the assurance of proper fatigue life in shot-peened components. This paper presents preliminary results from a feasibility study examining the use of ultrasonic and eddy current NDE methods for residual stress measurement in components where the stress has been introduced by shot peening. With an ultrasonic method, a variation of ultrasonic surface wave speed with shot peening intensity was measured. Near surface conductivity was measured by eddy current methods. Since the effective penetration depth of both methods employed is inversely related to the excitation frequency, by making measurements at different frequencies, each method has the potential to provide the stress-depth profile. Experiments were conducted on aluminum specimens (alloy 7075-T7351) peened within the Almen peening intensity range of 4C to 16C. The experimental results obtained demonstrate a correlation between peening intensity and Rayleigh wave velocity and between peening intensity and conductivity. The data suggests either of the methods may be suitable, with limitations, for detecting unsatisfactory levels of shot peening. Several factors were found to contribute to the measured responses: surface roughness, near surface plastic deformation (cold work) and residual stress. The contribution of each factor was studied experimentally. The feasibility of residual stress determination from the measured data is discussed

Standard practice for leaks using ultrasonics

CERN Document Server

American Society for Testing and Materials. Philadelphia

2011-01-01

1.1 Practice A, Pressurization—This practice covers procedures for calibration of ultrasonic instruments, location, and estimated measurements of gas leakage to atmosphere by the airborne ultrasonic technique. 1.2 In general practice this should be limited to leaks detected by two classifications of instruments, Class I and Class II. Class I instruments should have a minimum detectable leak rate of 6.7 × 10−7 mol/s (1.5 × 10−2 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Class II instruments should have a minimal detectable leak rate of 6.7 × 10−6 mol/s (1.5 × 10−1 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Refer to Guide E432 for additional information. 1.3 Practice B, Ultrasonic Transmitter—For object under test not capable of being pressurized but capable of having ultrasonic tone placed/injected into the test area to act as an ultrasonic leak trace source. 1.3.1 This practice is limited to leaks producing leakage o...

Applications of a nanocomposite-inspired in-situ broadband ultrasonic sensor to acousto-ultrasonics-based passive and active structural health monitoring.

Science.gov (United States)

Liu, Menglong; Zeng, Zhihui; Xu, Hao; Liao, Yaozhong; Zhou, Limin; Zhang, Zhong; Su, Zhongqing

2017-07-01

A novel nanocomposite-inspired in-situ broadband ultrasonic sensor previously developed, with carbon black as the nanofiller and polyvinylidene fluoride as the matrix, was networked for acousto-ultrasonic wave-based passive and active structural health monitoring (SHM). Being lightweight and small, this kind of sensor was proven to be capable of perceiving strain perturbation in virtue of the tunneling effect in the formed nanofiller conductive network when acousto-ultrasonic waves traverse the sensor. Proof-of-concept validation was implemented, to examine the sensor performance in responding to acousto-ultrasonic waves in a broad frequency regime: from acoustic emission (AE) of lower frequencies to guided ultrasonic waves (GUWs) of higher frequencies. Results have demonstrated the high fidelity, ultrafast response and high sensitivity of the sensor to acousto-ultrasonic waves up to 400kHz yet with an ultra-low magnitude (of the order of micro-strain). The sensor is proven to possess sensitivity and accuracy comparable with commercial piezoelectric ultrasonic transducers, whereas with greater flexibility in accommodating curved structural surfaces. Application paradigms of using the sensor for damage evaluation have spotlighted the capability of the sensor in compromising "sensing cost" with "sensing effectiveness" for passive AE- or active GUW-based SHM. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of an ultrasonic process for soil remediation

International Nuclear Information System (INIS)

Wu, J.M.; Huang, H.S.; Livengood, C.D.

1995-01-01

An ultrasonic process for the detoxification of carbon tetrachloride- (CCl 4 - ) contaminated soil was investigated in the laboratory by using a batch irradiation reactor equipped with a 600-W ultrasonic power supply operated at a frequency of 20 kHz. Key parameters studied included soil characteristics, irradiation time, CCl 4 concentration, steady-state operating temperature, applied ultrasonic-wave energy, and the ratio of soil to water in the system. The results of the experiments showed that (1) residual CCl 4 concentrations could be decreased with longer irradiation periods and (2) detoxification efficiency was proportional to steady-state operating temperature and applied ultrasonic-wave energy. The characteristics of the contaminated soil were found to be an important factor in the design of an ultrasonic detoxification system. A soil-phase CCl 4 concentration below 1 ppm (initial concentration of 56 ppm) was achieved through this process, indicating that the application of ultrasonic irradiation is feasible and effective in the detoxification of soil contaminated by organic compounds. On the basis of the experimental results, a schematic of a full-scale ultrasonic soil-detoxification system was developed. Improvements to this novel process are discussed

Crack initiation and propagation on the polymeric material ABS (Acrylonitrile Butadiene Styrene, under ultrasonic fatigue testing

Directory of Open Access Journals (Sweden)

G. M. Domínguez Almaraz

2015-10-01

Full Text Available Crack initiation and propagation have been investigated on the polymeric material ABS (Acrylonitrile Butadiene Styrene, under ultrasonic fatigue testing. Three controlled actions were implemented in order to carry out fatigue tests at very high frequency on this material of low thermal conductivity, they are: a The applying load was low to limit heat dissipation at the specimen neck section, b The dimensions of testing specimen were small (but fitting the resonance condition, in order to restraint the temperature gradient at the specimen narrow section, c Temperature at the specimen neck section was restrained by immersion in water or oil during ultrasonic fatigue testing. Experimental results are discussed on the basis of thermo-mechanical behaviour: the tail phenomenon at the initial stage of fatigue, initial shear yielding deformation, crazed development on the later stage, plastic strain on the fracture surface and the transition from low to high crack growth rate. In addition, a numerical analysis is developed to evaluate the J integral of energy dissipation and the stress intensity factor K, with the crack length

Ultrasonic characterization of vegetable oil product

International Nuclear Information System (INIS)

Sidek Hj Abd Aziz; Chow Sai Pew; Abdul Halim Shaari; Nor Azizah Shaari

1992-01-01

The ultrasonic wave velocity and attenuation of a number vegetable oil products were measured using an ultrasonic pulse echo overlap technique from room temperature up to 90 0 C. Among the liquid samples studied were refined bleach deodorized (RED) palm oil, palm olein, coconut oil, corn oil and soya bean oil. The velocity of sound in vegetable oil products varies from about 1200 to 200 ms-1 and decrease linearly as the temperature increases. The ultrasonic properties of the oil are much dependent on their viscosity, density, relaxation effect and vibrational anharmonicity

Ultrasonic-based membrane aided sample preparation of urine proteomes.

Science.gov (United States)

Jesus, Jemmyson Romário; Santos, Hugo M; López-Fernández, H; Lodeiro, Carlos; Arruda, Marco Aurélio Zezzi; Capelo, J L

2018-02-01

A new ultrafast ultrasonic-based method for shotgun proteomics as well as label-free protein quantification in urine samples is developed. The method first separates the urine proteins using nitrocellulose-based membranes and then proteins are in-membrane digested using trypsin. The enzymatic digestion process is accelerated from overnight to four minutes using a sonoreactor ultrasonic device. Overall, the sample treatment pipeline comprising protein separation, digestion and identification is done in just 3h. The process is assessed using urine of healthy volunteers. The method shows that male can be differentiated from female using the protein content of urine in a fast, easy and straightforward way. 232 and 226 proteins are identified in urine of male and female, respectively. From this, 162 are common to both genders, whilst 70 are unique to male and 64 to female. From the 162 common proteins, 13 are present at levels statistically different (p minimalism concept as outlined by Halls, as each stage of this analysis is evaluated to minimize the time, cost, sample requirement, reagent consumption, energy requirements and production of waste products. Copyright © 2017 Elsevier B.V. All rights reserved.

Remediation of Diesel Fuel Contaminated Sandy Soil using Ultrasonic Waves

Directory of Open Access Journals (Sweden)

Wulandari P.S.

2010-01-01

Full Text Available Ultrasonic cleaning has been used in industry for some time, but the application of ultrasonic cleaning in contaminated soil is just recently received considerable attention, it is a very new technique, especially in Indonesia. An ultrasonic cleaner works mostly by energy released from the collapse of millions of microscopic cavitations near the dirty surface. This paper investigates the use of ultrasonic wave to enhance remediation of diesel fuel contaminated sandy soil considering the ultrasonic power, soil particle size, soil density, water flow rate, and duration of ultrasonic waves application.

Cold and heat waves in the United States.

Science.gov (United States)

Barnett, A G; Hajat, S; Gasparrini, A; Rocklöv, J

2012-01-01

Extreme cold and heat waves, characterized by a number of cold or hot days in succession, place a strain on people's cardiovascular and respiratory systems. The increase in deaths due to these waves may be greater than that predicted by extreme temperatures alone. We examined cold and heat waves in 99 US cities for 14 years (1987-2000) and investigated how the risk of death depended on the temperature threshold used to define a wave, and a wave's timing, duration and intensity. We defined cold and heat waves using temperatures above and below cold and heat thresholds for two or more days. We tried five cold thresholds using the first to fifth percentiles of temperature, and five heat thresholds using the 95-99 percentiles. The extra wave effects were estimated using a two-stage model to ensure that their effects were estimated after removing the general effects of temperature. The increases in deaths associated with cold waves were generally small and not statistically significant, and there was even evidence of a decreased risk during the coldest waves. Heat waves generally increased the risk of death, particularly for the hottest heat threshold. Cold waves of a colder intensity or longer duration were not more dangerous. Cold waves earlier in the cool season were more dangerous, as were heat waves earlier in the warm season. In general there was no increased risk of death during cold waves above the known increased risk associated with cold temperatures. Cold or heat waves earlier in the cool or warm season may be more dangerous because of a build up in the susceptible pool or a lack of preparedness for extreme temperatures. Copyright © 2011 Elsevier Inc. All rights reserved.

The Dynamic Performance of Flexural Ultrasonic Transducers

Directory of Open Access Journals (Sweden)

Andrew Feeney

2018-01-01

Full Text Available Flexural ultrasonic transducers are principally used as proximity sensors and for industrial metrology. Their operation relies on a piezoelectric ceramic to generate a flexing of a metallic membrane, which delivers the ultrasound signal. The performance of flexural ultrasonic transducers has been largely limited to excitation through a short voltage burst signal at a designated mechanical resonance frequency. However, a steady-state amplitude response is not generated instantaneously in a flexural ultrasonic transducer from a drive excitation signal, and differences in the drive characteristics between transmitting and receiving transducers can affect the measured response. This research investigates the dynamic performance of flexural ultrasonic transducers using acoustic microphone measurements and laser Doppler vibrometry, supported by a detailed mechanical analog model, in a process which has not before been applied to the flexural ultrasonic transducer. These techniques are employed to gain insights into the physics of their vibration behaviour, vital for the optimisation of industrial ultrasound systems.

The Potential of Cold Plasma for Safe and Sustainable Food Production.

Science.gov (United States)

Bourke, Paula; Ziuzina, Dana; Boehm, Daniela; Cullen, Patrick J; Keener, Kevin

2018-06-01

Cold plasma science and technology is increasingly investigated for translation to a plethora of issues in the agriculture and food sectors. The diversity of the mechanisms of action of cold plasma, and the flexibility as a standalone technology or one that can integrate with other technologies, provide a rich resource for driving innovative solutions. The emerging understanding of the longer-term role of cold plasma reactive species and follow-on effects across a range of systems will suggest how cold plasma may be optimally applied to biological systems in the agricultural and food sectors. Here we present the current status, emerging issues, regulatory context, and opportunities of cold plasma with respect to the broad stages of primary and secondary food production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lithium niobate ultrasonic transducer design for Enhanced Oil Recovery.

Science.gov (United States)

Wang, Zhenjun; Xu, Yuanming; Gu, Yuting

2015-11-01

Due to the strong piezoelectric effect possessed by lithium niobate, a new idea that uses lithium niobate to design high-power ultrasonic transducer for Enhanced Oil Recovery technology is proposed. The purpose of this paper is to lay the foundation for the further research and development of high-power ultrasonic oil production technique. The main contents of this paper are as follows: firstly, structure design technique and application of a new high-power ultrasonic transducer are introduced; secondly, the experiment for reducing the viscosity of super heavy oil by this transducer is done, the optimum ultrasonic parameters for reducing the viscosity of super heavy oil are given. Experimental results show that heavy large molecules in super heavy oil can be cracked into light hydrocarbon substances under strong cavitation effect caused by high-intensity ultrasonic wave. Experiment proves that it is indeed feasible to design high-power ultrasonic transducer for ultrasonic oil production technology using lithium niobate. Copyright © 2015 Elsevier B.V. All rights reserved.

Degradation of acephate using combined ultrasonic and ozonation method

Directory of Open Access Journals (Sweden)

Bin Wang

2015-07-01

Full Text Available The degradation of acephate in aqueous solutions was investigated with the ultrasonic and ozonation methods, as well as a combination of both. An experimental facility was designed and operation parameters such as the ultrasonic power, temperature, and gas flow rate were strictly controlled at constant levels. The frequency of the ultrasonic wave was 160 kHz. The ultraviolet-visible (UV-Vis spectroscopic and Raman spectroscopic techniques were used in the experiment. The UV-Vis spectroscopic results show that ultrasonication and ozonation have a synergistic effect in the combined system. The degradation efficiency of acephate increases from 60.6% to 87.6% after the solution is irradiated by a 160 kHz ultrasonic wave for 60 min in the ozonation process, and it is higher with the combined method than the sum of the separated ultrasonic and ozonation methods. Raman spectra studies show that degradation via the combined ultrasonic/ozonation method is more thorough than photocatalysis. The oxidability of nitrogen atoms is promoted under ultrasonic waves. Changes of the inorganic ions and degradation pathway during the degradation process were investigated in this study. Most final products are innocuous to the environment.

Ultrasonic Abrasive Removal Of EDM Recast

Science.gov (United States)

Mandel, Johnny L.; Jacobson, Marlowe S.

1990-01-01

Ultrasonic abrasive process removes layer of recast material generated during electrical-discharge machining (EDM) of damper pocket on turbine blade. Form-fitted tool vibrated ultrasonically in damper pocket from which material removed. Vibrations activate abrasive in pocket. Amount of material removed controlled precisely.

Optimisation of thallium ''1223'' high-temperature superconducting wire by a single-stage cold deformation process. [TlPbSrCaCuO

Energy Technology Data Exchange (ETDEWEB)

Glowacki, B A [IRC in Superconductivity, Cambridge (United Kingdom) Materials Science and Metallurgy, Cambridge (United Kingdom); Ashworth, S P [BICC Cables Ltd., Erith (United Kingdom)

1992-09-15

Superconducting tapes containing (Tl[sub 0.5]Pb[sub 0.5])Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub 9] were manufactured by a powder-in-tube technique and a single annealing stage. The (Tl[sub 0.5]Pb[sub 0.5])Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub 9] forms a ''1223'' structure with a Tc of over 120 K. A cold pressing stage was found to be necessary to achieve the higher J[sub c] values at 77 K. The transport J[sub c] was found to depend on: the annealing temperature, annealing time and pressing pressure. SEM examination of the Tl-1223 grain structure showed a marked difference between rolled and pressed tapes. This is ascribed to the production of a lead-rich phase during pressing, this is supported by XRD evidence. No significant degree of grain alignment was found in the Tl-1223 tapes, either by XRD analysis or by the measurement of transport critical current in applied magnetic fields. (orig.).

Fundamentals of Medical Ultrasonics

CERN Document Server

Postema, Michiel

2011-01-01

This book sets out the physical and engineering principles of acoustics and ultrasound as used for medical applications. It covers the basics of linear acoustics, wave propagation, non-linear acoustics, acoustic properties of tissue, transducer components, and ultrasonic imaging modes, as well as the most common diagnostic and therapeutic applications. It offers students and professionals in medical physics and engineering a detailed overview of the technical aspects of medical ultrasonic imaging, whilst serving as a reference for clinical and research staff.

Assessing ultrasonic examination results

International Nuclear Information System (INIS)

Deutsch, V.; Vogt, M.

1977-01-01

Amongst nondestructive examination methods, the ultrasonic examination plays an important role. The reason why its scope of application is so wide is because the sound conducting capacity is the only property the material of a test specimen has to have. As the fields are so manifold, only main aspects can be described briefly. The list of references, however, is very extensive and gives plenty of information of all the problems concerning the assessment of ultrasonic examination results. (orig./RW) [de

Ultrasonically-assisted Thermal Stir Welding System

Science.gov (United States)

Ding, R. Jeffrey (Inventor)

2014-01-01

A welding head assembly has a work piece disposed between its containment plates' opposing surfaces with the work piece being maintained in a plastic state thereof at least in a vicinity of the welding head assembly's stir rod as the rod is rotated about its longitudinal axis. The welding head assembly and the work piece experience relative movement there between in a direction perpendicular to the rod's longitudinal axis as the work piece is subjected to a compressive force applied by the containment plates. A first source coupled to the first containment plate applies a first ultrasonic wave thereto such that the first ultrasonic wave propagates parallel to the direction of relative movement. A second source coupled to the second containment plate applies a second ultrasonic wave thereto such that the second ultrasonic wave propagates parallel to the direction of relative movement.propagates parallel to the direction of relative movement.

Development of computer-controlled ultrasonic image processing system for severe accidents research

International Nuclear Information System (INIS)

Koo, Kil Mo; Kang, Kyung Ho; Kim, Jong Tai; Kim, Jong Whan; Cho, Young Ro; Ha, Kwang Soon; Park, Rae Jun; Kim, Sang Baik; Kim, Hee Dong; Sim, Chul Moo

2000-07-01

In order to verify in-vessel corium cooling mechanism, LAVA(Lower-plenum Arrested Vessel Attack) experiment is being performed as a first stage proof of principle test. The aims of this study are to find a gap formation between corium melt and reactor lower head vessel, to verify the principle of the gap formation and to analyze the effect of the gap formation on the thermal behavior of corium melt and the lower plenum. This report aims at developing a computer controlled image signal processing system which is able to improve visualization and to measure the gap distribution with 3-dimensional planar image using a time domain signal analysis method as a part of the ultrasonic pulse echo methods and a computerized position control system. An image signal processing system is developed by independently developing an ultrasonic image signal processing technique and a PC controlled position control system and then combining both systems

Development of computer-controlled ultrasonic image processing system for severe accidents research

Energy Technology Data Exchange (ETDEWEB)

Koo, Kil Mo; Kang, Kyung Ho; Kim, Jong Tai; Kim, Jong Whan; Cho, Young Ro; Ha, Kwang Soon; Park, Rae Jun; Kim, Sang Baik; Kim, Hee Dong; Sim, Chul Moo

2000-07-01

In order to verify in-vessel corium cooling mechanism, LAVA(Lower-plenum Arrested Vessel Attack) experiment is being performed as a first stage proof of principle test. The aims of this study are to find a gap formation between corium melt and reactor lower head vessel, to verify the principle of the gap formation and to analyze the effect of the gap formation on the thermal behavior of corium melt and the lower plenum. This report aims at developing a computer controlled image signal processing system which is able to improve visualization and to measure the gap distribution with 3-dimensional planar image using a time domain signal analysis method as a part of the ultrasonic pulse echo methods and a computerized position control system. An image signal processing system is developed by independently developing an ultrasonic image signal processing technique and a PC controlled position control system and then combining both systems.

Development of an intelligent ultrasonic welding defect classification software

International Nuclear Information System (INIS)

Song, Sung Jin; Kim, Hak Joon; Jeong, Hee Don

1997-01-01

Ultrasonic pattern recognition is the most effective approach to the problem of discriminating types of flaws in weldments based on ultrasonic flaw signals. In spite of significant progress in the research on this methodology, it has not been widely used in many practical ultrasonic inspections of weldments in industry. Hence, for the convenient application of this approach in many practical situations, we develop an intelligent ultrasonic signature classification software which can discriminate types of flaws in weldments based on their ultrasonic signals using various tools in artificial intelligence such as neural networks. This software shows the excellent performance in an experimental problem where flaws in weldments are classified into two categories of cracks and non-cracks. This performance demonstrates the high possibility of this software as a practical tool for ultrasonic flaw classification in weldments.

Backward ray tracing for ultrasonic imaging

NARCIS (Netherlands)

Breeuwer, R.

1990-01-01

Focused ultrasonic beams frequently pass one or more media interfaces, strongly affecting the ultrasonic beamshape and focusing. A computer program, based on backward ray tracing was developed to compute the shape of a corrected focusing mirror. This shape is verified with another program; then the

Ultrasonic imaging of metastatic carcinoma in thyroid gland

International Nuclear Information System (INIS)

Bai Ling; Yang Tao; Tang Ying; Mao Jingning; Chen Wei; Wang Wei

2008-01-01

Objectives: To explore the ultrasonic findings of metastatic thyroid carcinoma and to evaluate the diagnostic value of the ultrasonic imaging for patients with metastatic thyroid neoplasm. Methods: The ultrasonic imaging characteristics of ten patients who were diagnosed with metastatic thyroid carcinoma were retrospectively analyzed. In all the cases, fine-needle aspiration cytology (FNAC) of the thyroid was performed during the clinical diagnosis. Results: The ultrasonic images of the ten patients fell into four types: multiple nodules in the thyroid, single nodule in the thyroid, diffuse calcification and heterogeneous echo. Seven cases showed speckled calcific foci. Abnormal blood flow signal was found in 9 cases. Conclusion: The ultrasonic findings of metastatic carcinoma in the thyroid gland are various and non-specific. Color Doppler ultrasound may provide ample evidence. The diagnosis depends on FNAC. (authors)

Effect of Ti solute on the recovery of cold-rolled V-Ti alloys

International Nuclear Information System (INIS)

Leguey, T.; Munoz, A.; Pareja, R.

1999-01-01

The recovery characteristics of cold-rolled pure V and V-Ti alloys with compositions of 0.3, 1 and 4.5 at.% Ti have been investigated by positron annihilation spectroscopy. The recovery is accomplished in two stages. Fifty percent cold rolling induces the formation of microvoids in V-0.3Ti and V-1Ti but not in V-4.5Ti. The first recovery stage in pure V, V-0.3Ti and V-1Ti starts with the dissolution of microvoids. The recovery curves of the annihilation parameters for the alloys indicate the formation of Ti-rich precipitates during the first recovery stage. These precipitates act as very efficient vacancy sinks. The second recovery stage starting for annealing temperatures above ≅1150 K is attributed to annealing of vacancies associated to the precipitates. (orig.)

Overview of the ultrasonic instrumentation research in the MYRRHA project

Energy Technology Data Exchange (ETDEWEB)

Dierckx, M.; Leysen, W.; Van Dyck, D. [Belgian Nuclear Research Center SCK.CEN (Belgium)

2015-07-01

The Belgian Nuclear Research Centre SCK.CEN is in the process of developing MYRRHA, a new generation IV fast flux research reactor to replace the aging BR2. MYRRHA is conceptualized as an accelerator driven system cooled with lead bismuth eutectic mixture (LBE). As LBE is opaque to visual light, ultrasonic measurement techniques are employed as the main technology to provide feedback where needed. This paper we will give an overview of the R and D at SCK.CEN with respect to ultrasonic instrumentation in heavy liquid metals. High temperature ultrasonic transducers are deployed into the reactor to generate and receive the required ultrasonic signals. The ultrasonic waves are generated and sensed by means of a piezo-electric disc at the heart of the transducer. The acoustic properties of commonly used piezo-electric materials match rather well with the acoustic properties of heavy liquid metals, simplifying the design and construction of high bandwidth ultrasonic transducers for use in heavy liquid metals. The ultrasonic transducers will operate in a liquid metal environment, where radiation and high temperature limit the choice of materials for construction. Moreover, the high surface tension of the liquid metal hinders proper wetting of the transducer, required for optimal transmission and reception of the ultrasonic waves. In a first part of the paper, we will discuss the effect of these parameters on the performance of the overall ultrasonic system. In the second part of the paper, past, present and future ultrasonic experiments in LBE will be reviewed. We will show the results of an experiment where a transducer is scanned near the free surface of an LBE pool to render ultrasonic images of objects submerged in the heavy liquid metal. Additionally, the preliminary results of an ongoing experiment that measures the evolution of LBE wetting on different types of metals and various surface conditions will be reported. The evolution of wetting is an important

Ultrasonic testing of materials at level 2

International Nuclear Information System (INIS)

1988-06-01

Ultrasonic inspection is a nondestructive method in which high frequency sound waves are introduced into the material being inspected. Ultrasonic testing has a superior penetrating power to radiography and can detect flaws deep in the test specimen (say up to about 6 to 7 meters of steel). It is quite sensitive to small flaws and allows the precise determination of the location and size of the flaws. Basic ultrasonic test methods such as the through transmission method and the resonance method, sensors and testing techniques are described. Pulse echo type flaw detectors and their applications for inspection of welds are surveyed. Ultrasonic standards, calibration of the equipment and evaluation methods are presented. Examples of practical applications in welding, casting and forging processes are given. Figs and tabs

Ultrasonic thermometry for nuclear power plants

International Nuclear Information System (INIS)

Saravana Kumar, S.; Arunraj, A.L.R.; Swaminathan, K.

2013-01-01

Ultrasonic transducer provides a method of measurement of temperature in industrial tanks and boilers containing different liquids with varied salt content. This method is used to measure the average temperature continuously where other traditional methods available do not offer. Traditional methods used for temperature measurement like infrared thermometers, thermocouples, measures temperature at a single location. Numerous thermocouples are to be fixed at various part of the boiler in order to measure the temperature of the entire boiler, which incurs high cost. Reliability of the system decreases, with increasing number of thermocouples. When they fail at a point, the time incurred in finding the faulty part or faulty thermocouple is high. Ultrasonic transducer provides continuous measurement for all different characteristic liquids with higher accuracy and lesser response time. Fault location and clearance time is also less in ultrasonic measurement method, since only a couple of transducers used for the entire boiler structure. Additionally ultrasonic thermometry along support measuring electronic system can be built of low cost. (author)

Analysis of Ultrasonic Resonance Signal in Multi-Layered Structure

International Nuclear Information System (INIS)

Kim, Jae Hoon; Kim, Dong Ryun

2012-01-01

Ultrasonic testing are far superior to other nondestructive tests for detecting the disbond interface which occurred in adhesive interface. However, a solid rocket motor consisting of a steel case, rubber insulation, liner, and propellant poses many difficulties for analyzing ultrasonic waves because of the superposition of reflected waves and large differences in acoustic impedance of various materials. Therefore, ultrasonic tests for detecting the disbond interface in solid rocket motor have been applied in very limited areas between the steel case and rubber insulation using an automatic C-scan system. The existing ultrasonic test cannot detect the disbond interface between the liner and propellant of a solid rocket motor because most of the ultrasonic waves are absorbed in the rubber material which has low acoustic impedance. This problem could be overcome by analyzing the resonance frequency from the frequency spectrum using the ultrasonic resonance method. In this paper, a new technique to detect the disbond interface between the liner and propellant using ultrasonic resonance characteristics is discussed in detail.

Analysis of Ultrasonic Resonance Signal in Multi-Layered Structure

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Hoon [Dept. of Mechanical Design Engineering, Chungnam National University, Daejeon (Korea, Republic of); Kim, Dong Ryun [Agency for Defense Development, Daejeon (Korea, Republic of)

2012-08-15

Ultrasonic testing are far superior to other nondestructive tests for detecting the disbond interface which occurred in adhesive interface. However, a solid rocket motor consisting of a steel case, rubber insulation, liner, and propellant poses many difficulties for analyzing ultrasonic waves because of the superposition of reflected waves and large differences in acoustic impedance of various materials. Therefore, ultrasonic tests for detecting the disbond interface in solid rocket motor have been applied in very limited areas between the steel case and rubber insulation using an automatic C-scan system. The existing ultrasonic test cannot detect the disbond interface between the liner and propellant of a solid rocket motor because most of the ultrasonic waves are absorbed in the rubber material which has low acoustic impedance. This problem could be overcome by analyzing the resonance frequency from the frequency spectrum using the ultrasonic resonance method. In this paper, a new technique to detect the disbond interface between the liner and propellant using ultrasonic resonance characteristics is discussed in detail.

The Round robin test of the PISC-2 programme: plates and ultrasonic procedures used PISC 2 report N.2. Final issue

International Nuclear Information System (INIS)

1986-09-01

Ultrasonic testing is widely used for detecting, locating and sizing defects in primary circuit elements at various stages of plant life. The successive PISC projects have together made up a most notable sustained international effort to assess the effectiveness of these inspection techniques. The Plate Inspection Steering Committee (PISC-I) programme (1976-1980) was intended to establish the capabilities of manual ultrasonic procedure based on the 1974 ASME Code Section XI Procedure. The Programme for the Inspection of Steel Components (PISC-II, 1981-1986) constitutes a broader based evaluation of the best performance obtainable by modern ultrasonic techniques under optimal conditions. The present paper is the second in a series of reports currently being issued which describe the results of the PISC-II studies. Included are descriptions of the four round robin test plates and of the ultrasonic procedures applied to them by the participating inspection teams. The report also lists the participating organisations and gives the time schedule of the tests and an indication of the costs incurred

Training methods in non-destructive examination with ultrasonic testing

International Nuclear Information System (INIS)

Walte, F.

1986-01-01

German concept for inspection of LWR, leak before break, basic safety; General inspection methods; Ultrasonic inspection - basic principle, generation of ultrasound, bulk and surface waves, piezo electric and electromagnetic transducers, energy balance, scattering and adsorption, divergence; Ultra techniques in compliance with KTA-rules - pulse-echo, tandem, throughtransmission; Valuation of ultrasonic indications; Pre- and in-service inspection; Practical part - ultrasonic equipment, ultrasonic piezo electric transducers, wall thickness measurement, crack depth measurement with potential drop technique. (orig.)

Ultrasonic Cleaning of Nuclear Steam Generator by Micro Bubble

Energy Technology Data Exchange (ETDEWEB)

Jeong, Woo Tae [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of); Kim, Sang Tae; Yoon, Sang Jung [Sae-An Engineering Co., Seoul (Korea, Republic of)

2012-05-15

In this paper, we present ultrasonic cleaning technology for a nuclear steam generator using micro bubble. We could extend the boundary of ultrasonic cleaning by using micro bubbles in water. Ultrasonic energy measured was increased about 5 times after the generation of micro bubbles in water. Furthermore, ultrasound energy was measured to be strong enough to create cavitation even though the ultrasound sensor was about 2 meters away from the ultrasonic transducer

Ultrasonic inspection development at HEDL

International Nuclear Information System (INIS)

Day, C.K.; Mech, S.J.; Michaels, T.E.; Dixon, N.E.

1978-01-01

Ultrasonic testing methods and equipment are being developed to support preservice and in-service inspection of selected FFTF welds. A digital computer system is employed in the analysis of both simulated FFTF pipe sections and plate specimens containing fatigue cracks. It is anticipated that test evaluation standards containing fatigue cracks will partially eliminate questions formerly associated with weld test calibration producers by providing natural cracks which follow grain boundaries and stress patterns resembling piping situ conditions. Studies have revealed that commercial transducers may satisfy LMFBR ultrasonic pipe inspection applications: The test system evaluation included transducers and wedge coupling and fluid coupling materials which exhibited acceptable performance at temperatures to 2300C. Results are presented that demonstrate the feasibility of ultrasonic inspection of components immersed in sodium at temperatures to 2600C. (UK)

Effect of decision making on ultrasonic examination performance

International Nuclear Information System (INIS)

Harris, D.H.

1992-05-01

A decision aid was developed to overcome examiner limitations in information processing and decision making during ultrasonic examinations. The aid provided a means of noting signal characteristics as they were observed during the examination, and of presenting them simultaneously for decision making. The aid also served as a way of providing detailed feedback on examination performance during training. The aid was incorporated into worksheets used for the conduct of practice examinations during ultrasonic examination training. To support the introduction and use of the decision aid, one hour of supplementary training was inserted in an existing 64-hour training course on ultrasonic detection of defects. This study represented a modest step in improving the performance of ultrasonic examinations in nuclear power plants. Findings indicated that aided decision making supported by limited training can significantly improve ultrasonic detection performance

Status and perspective of development of cold moderators at the IBR-2 reactor

International Nuclear Information System (INIS)

Kulikov, S; Shabalin, E

2012-01-01

The modernized IBR-2M reactor will start its operation with three water grooved moderators in 2011. Afterwards, they will be exchanged by a new complex of moderators. The complex consists of three so-called kombi-moderators, each of them containing a pre-moderator, a cold moderator, grooved ambient water moderators and post-moderators. They are mounted onto three moveable trolleys that serve to deliver and install moderators near the reactor core. The project is divided in three stages. In 2012 the first stage of development of complex of moderators will be finished. The water grooved moderator will be replaced with the new kombi-moderator for beams nos. 7, 8, 10, 11. Main parameters of moderators for this direction will be studied then. The next stages will be done for beams nos. 2-3 and for beams nos. 1, 9, 4-6, consequently. Cold moderator chambers at the modernized IBR-2 reactor are filled with thousands of beads (∼3.5 - 4 mm in diameter) of moderating material. The cold helium gas flow delivers beads from the charging device to the moderator during the fulfillment process and cools down them during the reactor cycle. The mixture of aromatic hydrocarbons (mesithylen and m-xylen) has been chosen as moderating material. The explanation of the choice of material for novel cold neutron moderators, configuration of moderator complex for the modernized IBR-2 reactor and the main results of optimization of moderator complex for the third stage of moderator development are discussed in the article.

Status and perspective of development of cold moderators at the IBR-2 reactor

Science.gov (United States)

Kulikov, S.; Shabalin, E.

2012-03-01

The modernized IBR-2M reactor will start its operation with three water grooved moderators in 2011. Afterwards, they will be exchanged by a new complex of moderators. The complex consists of three so-called kombi-moderators, each of them containing a pre-moderator, a cold moderator, grooved ambient water moderators and post-moderators. They are mounted onto three moveable trolleys that serve to deliver and install moderators near the reactor core. The project is divided in three stages. In 2012 the first stage of development of complex of moderators will be finished. The water grooved moderator will be replaced with the new kombi-moderator for beams #7, 8, 10, 11. Main parameters of moderators for this direction will be studied then. The next stages will be done for beams #2-3 and for beams #1, 9, 4-6, consequently. Cold moderator chambers at the modernized IBR-2 reactor are filled with thousands of beads (~3.5 - 4 mm in diameter) of moderating material. The cold helium gas flow delivers beads from the charging device to the moderator during the fulfillment process and cools down them during the reactor cycle. The mixture of aromatic hydrocarbons (mesithylen and m-xylen) has been chosen as moderating material. The explanation of the choice of material for novel cold neutron moderators, configuration of moderator complex for the modernized IBR-2 reactor and the main results of optimization of moderator complex for the third stage of moderator development are discussed in the article.

Resistivity recovery of neutron-irradiated and cold-worked thorium

International Nuclear Information System (INIS)

Tang, J.T.

1977-02-01

Results from a study of the resistivity recovery of neutron-irradiated and cold-worked thorium on isochronal annealing, activation energies, and isothermal annealing and kinetics are discussed. The nature and extent of radiation effects on the resistivity of thorium at 80 0 K, interpretation of stage II recovery above 80 0 K, and activation energy and interpretation of stage III recovery are also discussed. There are 79 references

On-line ultrasonic gas entrainment monitor

International Nuclear Information System (INIS)

Day, C.K.; Pedersen, H.N.

1978-01-01

Apparatus employing ultrasonic energy for detecting and measuring the quantity of gas bubbles present in liquids being transported through pipes is described. An ultrasonic transducer is positioned along the longitudinal axis of a fluid duct, oriented to transmit acoustic energy radially of the duct around the circumference of the enclosure walls. The back-reflected energy is received centrally of the duct and interpreted as a measure of gas entrainment. One embodiment employs a conical reflector to direct the transmitted acoustic energy radially of the duct and redirect the reflected energy back to the transducer for reception. A modified embodiment employs a cylindrical ultrasonic transducer for this purpose

Comparison of the Benefit Feeling Rate Based on the Sho of OTC Kakkonto, Cold Remedy and Cold Remedy with Kakkonto Combination Product.

Science.gov (United States)

Okita, Mitsuyoshi; Yayoshi, Yuki; Ohara, Kousuke; Negishi, Akio; Akimoto, Hayato; Inoue, Naoko; Numajiri, Sachihiko; Ohshima, Shigeru; Honma, Seiichi; Oshima, Shinji; Kobayashi, Daisuke

2017-10-01

Kakkonto (KK), a traditional Japanese Kampo formulation for cold and flu, is generally sold as an OTC pharmaceuticals used for self-medication. Kampo formulations should be used according to the Sho-symptoms of Kampo medicine. These symptoms refer to the subjective symptoms themselves. Although with OTC pharmaceuticals, this is often not the case. We surveyed the relationship of agreement of Sho with the benefit feeling rate (BFR) of patients who took KK (n=555), cold remedies with KK (CK, n=315), and general cold remedies (GC, n=539) using internet research. BFR of a faster recovery was greater in participants who took the medication early and who had confidence in their physical strength in all treatment groups. BFR was significantly higher in the GC group than in the KK group for patients with headache, runny nose, blocked nose, sneezing, and cough. BFR was also significantly higher in the GC group than in the CK group for headache (males) and cough (females). BFR was the highest in the KK group for stiff shoulders. All cold remedies were more effective when taken early, and the larger the number of Sho that a patient had, the greater the BFR increased. Therefore, a cold remedy is expected to be most effective when there are many cold symptoms and when it is taken at an early stage of the common cold.

Enhancement of the reliability of automated ultrasonic inspections using tools of quantitative NDT

International Nuclear Information System (INIS)

Kappes, W.; Baehr, W.; Kroening, M.; Schmitz, V.

1994-01-01

To achieve reliable test results from automated ultrasonic inspection of safety related components, optimization and integral consideration of the various inspection stages - inspection planning, inspection performance and evaluation of results - are indispensable. For this purpose, a large potential of methods is available: advanced measurement techniques, mathematical-numerical modelling processes, artificial intelligence tools, data bases and CAD systems. The potential inherent in these methods to enhance inspection reliability is outlined by way of different applications. (orig.) [de

A flow meter for ultrasonically measuring the flow velocity of fluids

DEFF Research Database (Denmark)

2015-01-01

The invention regards a flow meter for ultrasonically measuring the flow velocity of fluids comprising a duct having a flow channel with an internal cross section comprising variation configured to generate at least one acoustic resonance within the flow channel for a specific ultrasonic frequency......, and at least two transducers for generating and sensing ultrasonic pulses, configured to transmit ultrasonic pulses at least at said specific ultrasonic frequency into the flow channel such that the ultrasonic pulses propagate through a fluid flowing in the flow channel, wherein the flow meter is configured...

Bulk viscosity and ultrasonic attenuation in liquid metals

International Nuclear Information System (INIS)

Awasthi, O.N.; Murthy, B.V.S.

1984-11-01

Ultrasonic attenuation in simple liquid metals has been investigated using the thermodynamic theory of relaxation processes incorporating the concept of a two state model for the liquid near the melting point. Agreement of the results with the experimental values of the ultrasonic attenuation and bulk viscosity indicates that this might be an appropriate approach to explain the excess attenuation of ultrasonic waves in liquid metals. (author)

Ultrasonic techniques for fluids characterization

CERN Document Server

Povey, Malcolm J W

1997-01-01

This book is a comprehensive and practical guide to the use of ultrasonic techniques for the characterization of fluids. Focusing on ultrasonic velocimetry, the author covers the basic topics and techniques necessaryfor successful ultrasound measurements on emulsions, dispersions, multiphase media, and viscoelastic/viscoplastic materials. Advanced techniques such as scattering, particle sizing, and automation are also presented. As a handbook for industrial and scientific use, Ultrasonic Techniques for Fluids Characterization is an indispensable guide to chemists and chemical engineers using ultrasound for research or process monitoring in the chemical, food processing, pharmaceutical, cosmetic, biotechnology,and fuels industries. Key Features * Appeals to anyone using ultrasound to study fluids * Provides the first detailed description of the ultrasound profiling technique for dispersions * Describes new techniques for measuring phase transitions and nucleation, such as water/ice and oil/fat * Presents the l...

Cement-based materials' characterization using ultrasonic attenuation

Science.gov (United States)

Punurai, Wonsiri

The quantitative nondestructive evaluation (NDE) of cement-based materials is a critical area of research that is leading to advances in the health monitoring and condition assessment of the civil infrastructure. Ultrasonic NDE has been implemented with varying levels of success to characterize cement-based materials with complex microstructure and damage. A major issue with the application of ultrasonic techniques to characterize cement-based materials is their inherent inhomogeneity at multiple length scales. Ultrasonic waves propagating in these materials exhibit a high degree of attenuation losses, making quantitative interpretations difficult. Physically, these attenuation losses are a combination of internal friction in a viscoelastic material (ultrasonic absorption), and the scattering losses due to the material heterogeneity. The objective of this research is to use ultrasonic attenuation to characterize the microstructure of heterogeneous cement-based materials. The study considers a real, but simplified cement-based material, cement paste---a common bonding matrix of all cement-based composites. Cement paste consists of Portland cement and water but does not include aggregates. First, this research presents the findings of a theoretical study that uses a set of existing acoustics models to quantify the scattered ultrasonic wavefield from a known distribution of entrained air voids. These attenuation results are then coupled with experimental measurements to develop an inversion procedure that directly predicts the size and volume fraction of entrained air voids in a cement paste specimen. Optical studies verify the accuracy of the proposed inversion scheme. These results demonstrate the effectiveness of using attenuation to measure the average size, volume fraction of entrained air voids and the existence of additional larger entrapped air voids in hardened cement paste. Finally, coherent and diffuse ultrasonic waves are used to develop a direct

How cold is cold dark matter?

International Nuclear Information System (INIS)

Armendariz-Picon, Cristian; Neelakanta, Jayanth T.

2014-01-01

If cold dark matter consists of particles, these must be non-interacting and non-relativistic by definition. In most cold dark matter models however, dark matter particles inherit a non-vanishing velocity dispersion from interactions in the early universe, a velocity that redshifts with cosmic expansion but certainly remains non-zero. In this article, we place model-independent constraints on the dark matter temperature to mass ratio, whose square root determines the dark matter velocity dispersion. We only assume that dark matter particles decoupled kinetically while non-relativistic, when galactic scales had not entered the horizon yet, and that their momentum distribution has been Maxwellian since that time. Under these assumptions, using cosmic microwave background and matter power spectrum observations, we place upper limits on the temperature to mass ratio of cold dark matter today (away from collapsed structures). These limits imply that the present cold dark matter velocity dispersion has to be smaller than 54 m/s. Cold dark matter has to be quite cold, indeed

Cold welding of organic light emitting diode: Interfacial and contact models

Directory of Open Access Journals (Sweden)

J. Asare

2016-06-01

Full Text Available This paper presents the results of an analytical and computational study of the contacts and interfacial fracture associated with the cold welding of Organic Light Emitting diodes (OLEDs. The effects of impurities (within the possible interfaces are explored for contacts and interfacial fracture between layers that are relevant to model OLEDs. The models are used to study the effects of adhesion, pressure, thin film layer thickness and dust particle modulus (between the contacting surfaces on contact profiles around impurities between cold-welded thin films. The lift-off stage of thin films (during cold welding is then modeled as an interfacial fracture process. A combination of adhesion and interfacial fracture theories is used to provide new insights for the design of improved contact and interfacial separation during cold welding. The implications of the results are discussed for the design and fabrication of cold welded OLED structures.

Beat-Frequency/Microsphere Medical Ultrasonic Imaging

Science.gov (United States)

Yost, William T.; Cantrell, John H.; Pretlow, Robert A., III

1995-01-01

Medical ultrasonic imaging system designed to provide quantitative data on various flows of blood in chambers, blood vessels, muscles, and tissues of heart. Sensitive enough to yield readings on flows of blood in heart even when microspheres used as ultrasonic contrast agents injected far from heart and diluted by circulation of blood elsewhere in body.

A novel ultrasonic velocity sensing approach to monitoring state of charge of vanadium redox flow battery

International Nuclear Information System (INIS)

Chou, Yi-Sin; Hsu, Ning-Yih; Jeng, King-Tsai; Chen, Kuan-Hsiang; Yen, Shi-Chern

2016-01-01

Highlights: • This is the first to apply ultrasonic sensing technique to monitor SOC of VRB. • Ultrasound velocity is affected by concentration and temperature of a solution. • The ultrasonic sensing is applicable to both positive and negative sides of VRB. • An empirical model equation fits the results of this two-component system well. • The SOC of a VRB can be properly measured using ultrasonic sensing. - Abstract: A novel ultrasonic velocity sensing approach is proposed and investigated to monitor the state of charge (SOC) of a vanadium redox flow battery (VRB, or VRFB). The positive electrode is designated as the energy storage capacity-limiting one so that the molar ratio of the V"5"+ ion in the positive electrolyte solution determines the SOC of a VRB. The tested single-cell VRB is connected to an ultrasonic sensor and charged/discharged almost to its two extremes at a constant current of 2 A under various operating temperatures. It is found that the ultrasound velocity exhibits distinct variations in accordance with changes of vanadium ion compositions in the positive electrolyte solution as the SOC of the VRB varies. The SOC obtained can be depicted in a 3D plot in terms of ultrasound velocity and operating temperature. An empirical model equation is proposed and found to fit the experimental results of both charging and discharging stages quite well. The advantages of this SOC sensing approach are that it is totally independent of VRB operations and can be readily applied to both sides of the electrodes. It is expected to develop into a dependable method for accurate and real-time monitoring of SOC for VRB.

Ultrasonic sensor for sodium perspective device

International Nuclear Information System (INIS)

Ogawa, Fujio; Onuki, Koji.

1995-01-01

The present invention concerns an ultrasonic wave sensor for a sodium perspective device disposed in an FBR type reactor, which can change the directing angle of the ultrasonic sensor irrespective of the external conditions in liquid sodium. Namely, the sensor comprises (1) a sensor main body, (2) a diaphragm disposed on an oscillating surface of ultrasonic waves generated from the sensor main body, (3) a pressurizing and depressurizing nozzle connected to the sensor main body, and (4) a pressure detector disposed to these nozzles. A gas is charged/discharged to and from the sensor main body to control a gas pressure in the main body. If the gas pressure is made higher, the diaphragm is deformed convexly. If the gas pressure is lowered, the diaphragm is deformed concavely. The directing angle is greater when it is deformed a convexly, and it is smaller when it is deformed concavely. Accordingly, ultrasonic wave receiving/sending range in the sodium can be varied optionally by controlling the gas pressure in the main body. (I.S.)

The Effectiveness of Surface Coatings on Preventing Interfacial Reaction During Ultrasonic Welding of Aluminum to Magnesium

Science.gov (United States)

Panteli, Alexandria; Robson, Joseph D.; Chen, Ying-Chun; Prangnell, Philip B.

2013-12-01

High power ultrasonic spot welding (USW) is a solid-state joining process that is advantageous for welding difficult dissimilar material couples, like magnesium to aluminum. USW is also a useful technique for testing methods of controlling interfacial reaction in welding as the interface is not greatly displaced by the process. However, the high strain rate deformation in USW has been found to accelerate intermetallic compound (IMC) formation and a thick Al12Mg17 and Al3Mg2 reaction layer forms after relatively short welding times. In this work, we have investigated the potential of two approaches for reducing the IMC reaction rate in dissimilar Al-Mg ultrasonic welds, both involving coatings on the Mg sheet surface to (i) separate the join line from the weld interface, using a 100- μm-thick Al cold spray coating, and (ii) provide a diffusion barrier layer, using a thin manganese physical vapor deposition (PVD) coating. Both methods were found to reduce the level of reaction and increase the failure energy of the welds, but their effectiveness was limited due to issues with coating attachment and survivability during the welding cycle. The effect of the coatings on the joint's interface microstructure, and the fracture behavior have been investigated in detail. Kinetic modeling has been used to show that the benefit of the cold spray coating can be attributed to the reaction rate reverting to that expected under static conditions. This reduces the IMC growth rate by over 50 pct because at the weld line, the high strain rate dynamic deformation in USW normally enhances diffusion through the IMC layer. In comparison, the thin PVD barrier coating was found to rapidly break up early in USW and become dispersed throughout the deformation layer reducing its effectiveness.

Designing an in-situ ultrasonic nondestructive evaluation system for ultrasonic additive manufacturing

Science.gov (United States)

Nadimpalli, Venkata K.; Nagy, Peter B.

2018-04-01

Ultrasonic Additive Manufacturing (UAM) is a solid-state layer by layer manufacturing process that utilizes vibration induced plastic deformation to form a metallurgical bond between a thin layer and an existing base structure. Due to the vibration based bonding mechanism, the quality of components at each layer depends on the geometry of the structure. In-situ monitoring during and between UAM manufacturing steps offers the potential for closed-loop control to optimize process parameters and to repair existing defects. One interface that is most prone to delamination is the base/build interface and often UAM component height and quality are limited by failure at the base/build interface. Low manufacturing temperatures and favorable orientation of typical interface defects in UAM make ultrasonic NDE an attractive candidate for online monitoring. Two approaches for in-situ NDE are discussed and the design of the monitoring system optimized so that the quality of UAM components is not affected by the addition of the NDE setup. Preliminary results from in-situ ultrasonic NDE indicate the potential to be utilized for online qualification, closed-loop control and offline certification of UAM components.

Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen

Science.gov (United States)

2002-06-24

UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP012494 TITLE: Cold Antimatter Plasmas, and Aspirations for Cold...part numbers comprise the compilation report: ADP012489 thru ADP012577 UNCLASSIFIED Cold Antimatter Plasmas, and Aspirations for Cold Antihydrogen G...and positrons. The antiprotons come initially from the new Antiproton Decel- erator facility at CERN. Good control of such cold antimatter plasmas is

Computer simulation of ultrasonic waves in solids

International Nuclear Information System (INIS)

Thibault, G.A.; Chaplin, K.

1992-01-01

A computer model that simulates the propagation of ultrasonic waves has been developed at AECL Research, Chalk River Laboratories. This program is called EWE, short for Elastic Wave Equations, the mathematics governing the propagation of ultrasonic waves. This report contains a brief summary of the use of ultrasonic waves in non-destructive testing techniques, a discussion of the EWE simulation code explaining the implementation of the equations and the types of output received from the model, and an example simulation showing the abilities of the model. (author). 2 refs., 2 figs

Ultrasonic Transducer Peak-to-Peak Optical Measurement

Directory of Open Access Journals (Sweden)

Pavel Skarvada

2012-01-01

Full Text Available Possible optical setups for measurement of the peak-to-peak value of an ultrasonic transducer are described in this work. The Michelson interferometer with the calibrated nanopositioner in reference path and laser Doppler vibrometer were used for the basic measurement of vibration displacement. Langevin type of ultrasonic transducer is used for the purposes of Electro-Ultrasonic Nonlinear Spectroscopy (EUNS. Parameters of produced mechanical vibration have to been well known for EUNS. Moreover, a monitoring of mechanical vibration frequency shift with a mass load and sample-transducer coupling is important for EUNS measurement.

Determine bond strength by ultrasonic measurement

International Nuclear Information System (INIS)

Brown, C.M.

1978-01-01

Application of ultrasonic methods for the evaluation and measurement of bond strength has been the object of numerous investigations in the last fifteen years. Some investigators have reported good success (in limited application) while others have experienced dismal failure. One problem common to all investigations was the difficulty in extracting and isolating the many components which comprise the ultrasonic signal reflected from a bonded interface. Part of this problem was due to manually extracting individual parameters from large volumes of raw data. However, with the vast technology now available in the field of signal analysis and computerized data processing, it is feasible to isolate and analyze individual parameters within the ultrasonic signal for great volumes of raw data

Numerical shaping of the ultrasonic wavelet

International Nuclear Information System (INIS)

Bonis, M.

1991-01-01

Improving the performance and the quality of ultrasonic testing requires the numerical control of the shape of the driving signal applied to the piezoelectric transducer. This allows precise shaping of the ultrasonic field wavelet and corrections for the physical defects of the transducer, which are mainly due to the damper or the lens. It also does away with the need for an accurate electric matching. It then becomes feasible to characterize, a priori, the ultrasonic wavelet by means of temporal and/or spectral specifications and to use, subsequently, an adaptative algorithm to calculate the corresponding driving wavelet. Moreover, the versatility resulting from the numerical control of this wavelet allows it to be changed in real time during a test

Design of fresh food sensory perceptual system for cold chain logistics

OpenAIRE

Zhang Ying; Cheng Ruqi; Chen Shaohui

2018-01-01

According to the present stage low-level information of China's cold chain preservation, designed a kind of fresh food sensory perceptual system for cold chain logistics based on Internet of things. This system highly integrated applied many technologies such as the Internet of things technology, forecasting technology for fruits and vegetables preservation period, RFID and Planar bar code technology, big data and cloud computing technology and so on.Designed as a four-layer structure includi...

Review of ultrasonic irrigation in endodontics: increasing action of irrigating solutions

Science.gov (United States)

Mozo, Sandra; Llena, Carmen

2012-01-01

Introduction: Effective irrigant delivery and agitation are prerequisites for successful endodontic treatment. Ultrasonic irrigation can be performed with or without simultaneous ultrasonic instrumentation. Existing literature reveals that ultrasonic irrigation may have a very positive effect on chemical, biological and physical debridement of the root canal system as investigated in many in vitro studies. Objective: The purpose of this review article was to summarize and discuss the available information concerning ultrasonic irrigation in endodontics. Methods: This article presents an overview of ultrasonic irrigation methods and their debridement efficacy. In this paper the relevant literature on passive ultrasonic irrigation is reviewed. Information from original scientific papers or reviews listed in MEDLINE and Cochrane were included in the review. Results: The use of ultrasound in the irrigation procedure results in improved canal cleanliness, better irrigant transfer to the canal system, soft tissue debridement, and removal of smear layer and bacteria. There are many in vitro studies, but there is a need to standardize protocols, and correlate the clinical efficacy of ultrasonic devices with improved treatment outcomes. Understanding the basis of ultrasonic irrigation is fundamental for clinicians and researchers to improve the design and use of ultrasonic irrigation. Key words:Ultrasonic irrigation, ultrasound, smear layer, endodontics. PMID:22143738

Contact-free ultrasonic testing: applications to metrology and NDT

International Nuclear Information System (INIS)

Le Brun, A.

1988-01-01

In some cases classical ultrasonic testing is impossible because of adverse environment (high temperature, ionizing radiations, etc). Ultrasonic waves are created by laser impact and detected by electromagneto-acoustic transducers or laser interferometry. Association of ultrasonics generation by photoacoustic effect and reception by heterodyne interferometer is promising for the future [fr

Ultrasonic actuation for MEMS dormancy-related stiction reduction

Science.gov (United States)

Kaajakari, Ville; Kan, Shyi-Herng; Lin, Li-Jen; Lal, Amit; Rodgers, M. Steven

2000-08-01

The use of ultrasonic pulses incident on surface micromachines has been shown to reduce dormancy-related failure. We applied ultrasonic pulses from the backside of a silicon substrate carrying SUMMiT processed surface micromachined rotors, used earlier as ultrasonic motors. The amplitude of the pulses was less than what is required to actuate the rotor (sub-threshold actuation). By controlling the ultrasonic pulse exposure time it was found that pulsed samples had smaller actuation voltages as compared to non-pulsed samples after twelve-hour dormancy. This result indicates that the micromachine stiction to surfaces during dormant period can be effectively eliminated, resulting in long-term stability of surface micromachines in critical applications.

NEET In-Pile Ultrasonic Sensor Enablement-Final Report

Energy Technology Data Exchange (ETDEWEB)

J. Daw; J. Rempe; J. Palmer; P. Ramuhalli; R. Montgomery; H.T. Chien; B. Tittmann; B. Reinhardt; P. Keller

2014-09-01

Ultrasonic technologies offer the potential to measure a range of parameters during irradiation of fuels and materials, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes under harsh irradiation test conditions. There are two primary issues that currently limit in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. The harsh nature of in-pile testing and the variety of desired measurements demand that an enhanced signal processing capability be developed to make in-pile ultrasonic sensors viable. To address these issues, the NEET ASI program funded a three year Ultrasonic Transducer Irradiation and Signal Processing Enhancements project, which is a collaborative effort between the Idaho National Laboratory, the Pacific Northwest National Laboratory, the Argonne National Laboratory, and the Pennsylvania State University. The objective of this report is to document the objectives and accomplishments from this three year project. As summarized within this document, significant work has been accomplished during this three year project.

Extrinsic Fabry-Perot ultrasonic detector

Science.gov (United States)

Kidwell, J. J.; Berthold, John W., III

1996-10-01

We characterized the performance of a commercial fiber optic extrinsic Fabry-Perot interferometer for use as an ultrasonic sensor, and compared the performance with a standard lead zirconate titanate (PZT) detector. The interferometer was unstabilized. The results showed that the fiber sensor was about 12 times less sensitive than the PZT detector. Ultrasonic frequency response near 100 kHz was demonstrated. We describe the design of the fiber sensor, the details of the tests performed, and potential applications.

Hypothermic general cold adaptation induced by local cold acclimation.

Science.gov (United States)

Savourey, G; Barnavol, B; Caravel, J P; Feuerstein, C; Bittel, J H

1996-01-01

To study relationships between local cold adaptation of the lower limbs and general cold adaptation, eight subjects were submitted both to a cold foot test (CFT, 5 degrees C water immersion, 5 min) and to a whole-body standard cold air test (SCAT, 1 degree C, 2 h, nude at rest) before and after a local cold acclimation (LCA) of the lower limbs effected by repeated cold water immersions. The LCA induced a local cold adaptation confirmed by higher skin temperatures of the lower limbs during CFT and a hypothermic insulative general cold adaptation (decreased rectal temperature and mean skin temperature P adaptation was related to the habituation process confirmed by decreased plasma concentrations of noradrenaline (NA) during LCA (P general cold adaptation was unrelated either to local cold adaptation or to the habituation process, because an increased NA during SCAT after LCA (P syndrome" occurring during LCA.

Internal properties assessment in agar wood trees using ultrasonic velocity measurement

International Nuclear Information System (INIS)

Mohd Noorul Ikhsan Mohamed; Mohamad Pauzi Ismail; Mat Rasol Awang; Mohd Fajri Osman; Fakhruzi, M.; Hashim, M.M.

2010-01-01

This paper presents the application of ultrasonic velocity in agar wood trees (Aquilaria crassna) with the purpose of evaluating the relationship of the ultrasonic velocity to the variations of internal properties of trees. In this study, three circular cross-sectional discs from the freshly cut tree were selected as samples. First sample with a big hole (decay) in the middle, second sample with internal resinous and the last one is the sample with no defects. The through transmission ultrasonic testing method was carried out using Tico ultrasonic pulse velocity tester which is from Switzerland. Two-dimensional image of internal properties evaluation by an ultrasonic investigation was obtained using Matlab. The results showed that the ultrasonic wave cannot pass through the internal decay or resinous so that the wave went round it and thus ultrasonic wave velocity significantly decreased by increasing the hole or resinous. The difference in color of the image generated by Matlab software based on variation of ultrasonic velocity between the internal decay area and its surrounding area was obvious. Therefore, the properties of internal properties of the three could be detected by ultrasonic line imaging technique. (author)

Characterization of nuclear graphite elastic properties using laser ultrasonic methods

Science.gov (United States)

Zeng, Fan W.; Han, Karen; Olasov, Lauren R.; Gallego, Nidia C.; Contescu, Cristian I.; Spicer, James B.

2015-05-01

Laser ultrasonic methods have been used to characterize the elastic behaviors of commercially-available and legacy nuclear graphites. Since ultrasonic techniques are sensitive to various aspects of graphite microstructure including preferred grain orientation, microcrack orientation and porosity, laser ultrasonics is a candidate technique for monitoring graphite degradation and structural integrity in environments expected in high-temperature, gas-cooled nuclear reactors. Aspects of materials texture can be assessed by studying ultrasonic wavespeeds as a function of propagation direction and polarization. Shear wave birefringence measurements, in particular, can be used to evaluate elastic anisotropy. In this work, laser ultrasonic measurements of graphite moduli have been made to provide insight into the relationship between the microstructures and the macroscopic stiffnesses of these materials. In particular, laser ultrasonic measurements have been made using laser line sources to produce shear waves with specific polarizations. By varying the line orientation relative to the sample, shear wave birefringence measurements have been recorded. Results from shear wave birefringence measurements show that an isostatically molded graphite, such as PCIB, behaves isotropically, while an extruded graphite, such as H-451, displays significant ultrasonic texture. Graphites have complicated microstructures that depend on the manufacturing processes used, and ultrasonic texture in these materials could originate from grain orientation and preferred microcrack alignment. Effects on material isotropy due to service related microstructural changes are possible and the ultimate aim of this work is to determine the degree to which these changes can be assessed nondestructively using laser ultrasonics measurements.

Analysis of Ultrasonic Transmitted Signal for Apple using Wavelet Transform

International Nuclear Information System (INIS)

Kim, Ki Bok; Lee, Sang Dae; Choi, Man Yong; Kim, Man Soo

2005-01-01

This study was conducted to analyze the ultrasonic transmitted signal for apple using wavelet transform. Fruit consists of nonlinear visco-elastic properties such as flesh, an ovary and rind and lienee most ultrasonic wave is attenuated and its frequency is shifted during passing the fruit. Thus it is not easy to evaluate the internal quality of the fruit using typical ultrasonic parameters such as wave velocity, attenuation, and frequency spectrum. The discrete wavelet transform was applied to the ultrasonic transmitted signal for apple. The magnitude of the first peak frequency of the wavelet basis from the ultrasonic transmitted signal showed a close correlation to the storage time of apple

Ultrasonic filtration of industrial chemical solutions

Science.gov (United States)

Cosma, T.

1974-01-01

The practical results obtained as a result of filtering industrial chemical solutions under continuous flow conditions with the aid of an ultrasonic filter are presented. The main part of the assembly consists of an ultrasonic generator with an output power of about 400 W and the filtration assembly, in which there is a magnetostrictive amplifier constructed for 20.5 kHz. In addition to ensuring a continuous flow of filtered solution, ultrasonic filters can be replaced or cleaned at intervals of time that are 8-10 times greater than in the case of mechanical filters. They yield considerably better results as far as the size of the filtered particles is concerned. The parameters on which filtration quality depends are also presented.

Ultrasonic imaging in LMFBRs using digital techniques

International Nuclear Information System (INIS)

Fothergill, J.R.; McKnight, J.A.; Barrett, L.M.

Ultrasonic technology for providing images of components immersed in the opaque sodium of LMFBRs is being developed at RNL. For many years the application has been restricted by the unavailability of convenient ultrasonic sources and receivers capable of withstanding the reactor environment. Until recently, for example, important ultrasonic instrument design, such as for future sweep arms, had to be based on waveguided ultrasonics. RNL have developed an economic immersible transducer that can be deployed during reactor shut-down, when many demands for ultrasonic imaging are made. The transducer design is not suited at present to the sophisticated techniques of phased arrays; consequently image formation must depend on the physical scanning of a target using one or more transducers in pulse-echo mode. The difficulties of access into a fast reactor impose further restrictions. Some applications may involve easy scanning sequences, thus the sweep arm requires only a rotation to provide a map of the reactor core area. For a more detailed examination of the same area, however, special engineering solutions are needed to provide a more satisfactory scanning sequence. A compromise solution involving the rotating shield movement is being used for a PFR experiment to examine a limited area of the core. (author)

Hardware Developments of an Ultrasonic Tomography Measurement System

Directory of Open Access Journals (Sweden)

Hudabiyah ARSHAD AMARI

2010-01-01

Full Text Available This research provides new technique in ultrasonic tomography by using ultrasonic transceivers instead of using separate transmitter-receiver pair. The numbers of sensors or transducers used to acquire data plays an important role to generate high resolution tomography images. The configuration of these sensors is a crucial factor in the efficiency of data acquisition. Instead of using common separated transmitter – receiver, an alternative approach has been taken to use dual functionality ultrasonic transceiver. A prototype design of sensor’s jig that will hold 16 transceivers of 14.1mm has been design. Transmission-mode approach with fan beam technique has been used for sensing the flow of gas, liquid and solid. This paper also explains the circuitry designs for the Ultrasonic Tomography System.

Ultrasonic system for NDE of fruits and vegetables

International Nuclear Information System (INIS)

Jhang, Kyung Young; Jung, Gyoo Hong; Kim, Man Soo

1999-01-01

The nondestructive internal quality evaluation of agricultural products has been strongly required from the needs for individual inspection. In recent, ultrasonic wave has been considered as a solution for this problem. This study is to construct the ultrasonic inspection system for fruits and vegetables on the basis of pre-knowledge that general frequency band(higher than 100 kHz) ultrasonic waves do not transmitted well due to severe attenuation. Our system includes ultrasonic pulser and receiver, transducers(50 kHz), acoustic hem, pneumatic controller and signal processing units (PC). In order to confirm the performance, several samples (apple, pear, persimmon, kiwi fruit, potato and radish) were tested, and the results showed sufficient possibility to apply to NDE of fruits and vegetables.

SNS 2.1K Cold Box Turn-down Studies

International Nuclear Information System (INIS)

F. Casagrande; P.A. Gurd; D.R. Hatfield; M.P. Howell; W.H. Strong; D. Arenius; J. Creel; V. Ganni; P. Knudsen

2006-01-01

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory is nearing completion. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The 2.1K cold box consists of four stages of centrifugal compressors with LN2-cooled variable speed electric motors and magnetic bearings. The cryogenic system successfully supported the Linac beam commissioning at both 4.2K and 2.1K and has been fully operational since June 2005. This paper describes the control principles utilized and the experimental results obtained for the SNS cold compressors turn-down capability to about 30% of the design flow, and possible limitation of the frequency dependent power factor of the cold compressor electric motors, which was measured for the first time during commissioning. These results helped to support the operation of the Linac over a very broad and stable cold compressor operating flow range (refrigeration capacity) and pressure. This in turn helped to optimize the cryogenic system operating parameters, minimizing the utilities and improving the system reliability and availability

Phenomenally High Transduction Air/gas Transducers for Practical Non-Contact Ultrasonic Applications

Science.gov (United States)

Bhardwaj, Mahesh C.

2009-03-01

Based on novel acoustic impedance matching layers and high coupling piezoelectric materials this paper describes exceptionally high air/gas transduction ultrasonic transducers. By providing applications oriented performance of these transducers we also usher in the era of much desired Non-Contact Ultrasound (NCU) testing and analysis of a wide range of materials including early stage formation of materials such as uncured composite prepregs, green ceramics and powder metals, plastics, elastomers, porous, hygroscopic, chemically bonded and other materials. Besides quality control, ultimately NCU offers timely opportunities for cost-effective materials production, energy savings, and environment protection.

On line ultrasonic integrated backscatter

International Nuclear Information System (INIS)

Landini, L.; Picano, E.; Mazzarisi, A.; Santarelli, F.; Benassi, A.; De Pieri, G.

1988-01-01

A new equipment for on-line evaluation of index based on two-dimensional integrated backscatter from ultrasonic images is described. The new equipment is fully integrated into a B-mode ultrasonic apparatus which provides a simultaneous display of conventional information together with parameters of tissue characterization. The system has been tested with a backscattering model of microbubbles in polysaccharide solution, characterized by a physiological exponential time decay. An exponential fitting to the experimental data was performed which yielded r=0.95

Ultrasonic-assisted manufacturing processes: Variational model and numerical simulations

KAUST Repository

Siddiq, Amir

2012-04-01

We present a computational study of ultrasonic assisted manufacturing processes including sheet metal forming, upsetting, and wire drawing. A fully variational porous plasticity model is modified to include ultrasonic softening effects and then utilized to account for instantaneous softening when ultrasonic energy is applied during deformation. Material model parameters are identified via inverse modeling, i.e. by using experimental data. The versatility and predictive ability of the model are demonstrated and the effect of ultrasonic intensity on the manufacturing process at hand is investigated and compared qualitatively with experimental results reported in the literature. © 2011 Elsevier B.V. All rights reserved.

Cold Stress

Science.gov (United States)

... Publications and Products Programs Contact NIOSH NIOSH COLD STRESS Recommend on Facebook Tweet Share Compartir Workers who ... cold environments may be at risk of cold stress. Extreme cold weather is a dangerous situation that ...

Computer-aided ultrasonic inspection of steam turbine rotors

Energy Technology Data Exchange (ETDEWEB)

Mayer, K H; Weber, M; Weiss, M [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

1999-12-31

As the output and economic value of power plants increase, the detection and sizing of the type of flaws liable to occur in the rotors of turbines using ultrasonic methods assumes increasing importance. An ultrasonic inspection carried out at considerable expense is expected to bring to light all safety-relevant flaws and to enable their size to be determined so as to permit a fracture-mechanics analysis to assess the reliability of the rotor under all possible stresses arising in operation with a high degree of accuracy. The advanced computer-aided ultrasonic inspection of steam turbine rotors have improved reliability, accuracy and reproducibility of ultrasonic inspection. Further, there has been an improvement in the resolution of resolvable group indications by applying reconstruction and imagine methods. In general, it is also true for the advanced computer-aided ultrasonic inspection methods that, in the case of flaw-affected forgings, automated data acquisition provides a substantial rationalization and a significant documentation of the results for the fracture mechanics assessment compared to manual inspection. (orig.) 8 refs.

Computer-aided ultrasonic inspection of steam turbine rotors

Energy Technology Data Exchange (ETDEWEB)

Mayer, K.H.; Weber, M.; Weiss, M. [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

1998-12-31

As the output and economic value of power plants increase, the detection and sizing of the type of flaws liable to occur in the rotors of turbines using ultrasonic methods assumes increasing importance. An ultrasonic inspection carried out at considerable expense is expected to bring to light all safety-relevant flaws and to enable their size to be determined so as to permit a fracture-mechanics analysis to assess the reliability of the rotor under all possible stresses arising in operation with a high degree of accuracy. The advanced computer-aided ultrasonic inspection of steam turbine rotors have improved reliability, accuracy and reproducibility of ultrasonic inspection. Further, there has been an improvement in the resolution of resolvable group indications by applying reconstruction and imagine methods. In general, it is also true for the advanced computer-aided ultrasonic inspection methods that, in the case of flaw-affected forgings, automated data acquisition provides a substantial rationalization and a significant documentation of the results for the fracture mechanics assessment compared to manual inspection. (orig.) 8 refs.

The outcome of laparoscopic cholecystectomy by ultrasonic dissection.

LENUS (Irish Health Repository)

Sasi, Walid

2010-04-01

Electrocautery remains the main energy form used for dissection in laparoscopic cholecystectomy. However, due to its many risks the search continues for safer and more efficient forms of energy. This chapter assesses the outcomes of dissection using ultrasonic energy as compared to monopolar electrocautery during laparoscopic cholecystectomy. Studies included are trials of prospectively randomized adult patients with symptomatic gallstone disease subject either ultrasonic or monopolar electrocautery dissection during laparoscopic cholecystectomy. Seven trials were included in this review, with a total patient number of 695 randomized to two dissection methods: 340 in the electrocautery group and 355 in the ultrasonic group. Ultrasonic dissection is shown to be superior to monopolar electrocautery in laparoscopic cholecystectomy. Disadvantages include a difficult maneuvering technique and overall cost. Appropriate training programs may be implemented to overcome the first disadvantage, and it might be argued that given the combined cost of factors associated with standard clip and cautery technique, cost issues may be outweighed by the benefits of ultrasonic dissection. However, this necessitates further cost-benefit analysis.

Ultrasonic extraction of flavonoids and phenolics from loquat ...

African Journals Online (AJOL)

Administrator

2011-06-08

Jun 8, 2011 ... ultrasonic pharmaceutical managing machine (Sinobest electronic. Co. Ltd., Jining, Shangdong ... During the ultrasonic treatment, the temperature ..... essential oil extraction by a hydrodistillation process using a 2(4) complete ...

Nondestructive control of materials by ultrasonic tests

International Nuclear Information System (INIS)

Mercier, Noelle.

1974-01-01

A bibliographic study of nondestructive control methods of solids by ultrasonic tests, and of the ultrasonic emission of a transducer of finite dimension, is first presented. The principle of two of these methods is verified experimentally; they should permit the measurement of various physical parameters of solids, and the detection of local inhomogeneities. The first method calls upon the analysis of the ultrasonic signal (amplitude and phase), after it has crossed a constant thickness of a metallic specimen. This analysis reveals variations of attenuation and of ultrasonic propagation velocity within the specimen. A good spatial resolution is obtained by using 1mm-diameter probes. The second method leads, thanks to a test rig equipped with broad frequency band electrostatic transducers, to the knowledge of the attenuation law of the specimens as a function of frequency (present range: 5 to 15MHz); from this a classification of these specimens as regards their granulometry is deduced [fr

Advanced ultrasonic technology for natural gas measurement

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-11-15

In recent years, due to rising environmental and safety concerns, increasing commodity prices, and operational inefficiencies, a paradigm shift has been taking place with respect to gas measurement. The price of natural gas depends on the location, time of the year, and type of consumer. There is wide uncertainty associated with an orifice meter. This paper presents the use of advanced ultrasonic technology for the measurement of natural gas. For many years, multi-path ultrasonic meters with intelligent sensor technology have been used for gas measurement. This paper gives the various applications of ultrasonic technology along with their advantages and a draws a comparison with orifice meters. From the study it can be concluded that extensive advances in the use of ultrasonic technology for gas measurement have widened the areas of application and that varying frequencies combined with sealed transducer designs make it possible to measure atmospheric and sour gas in custody transfer process control and flaring accurately.

Frequency and amplitude dependences of molding accuracy in ultrasonic nanoimprint technology

International Nuclear Information System (INIS)

Mekaru, Harutaka; Takahashi, Masaharu

2009-01-01

We use neither a heater nor ultraviolet lights, and are researching and developing an ultrasonic nanoimprint as a new nano-patterning technology. In our ultrasonic nanoimprint technology, ultrasonic vibration is not used as a heat generator instead of the heater. A mold is connected with an ultrasonic generator, and mold patterns are pushed down and pulled up at a high speed into a thermoplastic. Frictional heat is generated by ultrasonic vibration between mold patterns and thermoplastic patterns formed by an initial contact force. However, because frictional heat occurs locally, the whole mold is not heated. Therefore, a molding material can be comprehensively processed at room temperature. A magnetostriction actuator was built into our ultrasonic nanoimprint system as an ultrasonic generator, and the frequency and amplitude can be changed between dc–10 kHz and 0–4 µm, respectively. First, the ultrasonic nanoimprint was experimented by using this system on polyethylene terephthalate (PET, T g = 69 °C), whose the glass transition temperature (T g ) is comparatively low in engineering plastics, and it was ascertained that the most suitable elastic material for this technique was an ethyl urethane rubber. In addition, we used a changeable frequency of the magnetostriction actuator, and nano-patterns in an electroformed-Ni mold were transferred to a 0.5 mm thick sheet of PET, polymethylmethacrylate (PMMA) and polycarbonate (PC), which are typical engineering plastics, under variable molding conditions. The frequency and amplitude dependence of ultrasonic vibration to the molding accuracy were investigated by measuring depth and width of imprinted patterns. As a result, regardless of the molding material, the imprinted depth was changed drastically when the frequency exceeded 5 kHz. On the other hand, when the amplitude of ultrasonic vibration grew, the imprinted depth gradually deepened. Influence of the frequency and amplitude of ultrasonic vibration was not

The digital ultrasonic test unit for automatic equipment

International Nuclear Information System (INIS)

Hiraoka, T.; Matsuyama, H.

1976-01-01

The operations and features of the ultrasonic test unit used and the digital data processing techniques employed are described. This unit is used for a few hundred multi-channel automatic ultrasonic test equipment

Research on Fatigue Damage of Compressor Blade Steel KMN-I Using Nonlinear Ultrasonic Testing

Directory of Open Access Journals (Sweden)

Pengfei Wang

2017-01-01

Full Text Available The fatigue damage of compressor blade steel KMN-I was investigated using nonlinear ultrasonic testing and the relation curve between the material nonlinearity parameter β and the fatigue life was obtained. The results showed that the nonlinearity parameter increased first and then decreased with the increase of the fatigue cycles. The microstructures were observed by scanning electron microscopy (SEM. It was found that some small defects like holes and pits appeared in the material matrix with the increase of the fatigue cycles, and the nonlinearity parameter increased correspondingly. The nonlinearity parameter reached the peak value when the microcracks initiated, and the nonlinearity parameter began to decrease when the microcracks further propagated to macrocracks. Therefore, it is proved that the nonlinearity parameter can be used to characterize the initiation of microcracks at the early stage of fatigue, and a method of evaluating the fatigue life of materials by nonlinear ultrasonic testing is proposed.

Design of ultrasonic probe and evaluation of ultrasonic waves on E.coli in Sour Cherry Juice

Directory of Open Access Journals (Sweden)

B Hosseinzadeh Samani

2015-09-01

Full Text Available Introduction: The common method used for juice pasteurization is the thermal method since thermal methods contribute highly to inactivating microbes. However, applying high temperatures would lead to inefficient effects on nutrition and food value. Such effects may include vitamin loss, nutritional flavor loss, non-enzyme browning, and protein reshaping (Kuldiloke, 2002. In order to decrease the adverse effects of the thermal pasteurization method, other methods capable of inactivation of microorganisms can be applied. In doing so, non-thermal methods including pasteurization using high hydrostatic pressure processing (HPP, electrical fields, and ultrasound waves are of interest (Chen and Tseng, 1996. The reason for diminishing microbial count in the presence of ultrasonic waves could be due to the burst of very tiny bubbles developed by ultrasounds which expand quickly and burst in a short time. Due to this burst, special temperature and pressure conditions are developed which could initiate or intensify several physical and/or chemical reactions. The aim of this study is to evaluate the non-thermal ultrasonic method and its effective factors on the E.coli bacteria of sour cherry. Materials and methods: In order to supply uniform ultrasonic waves, a 1000 W electric generator (Model MPI, Switzerland working at 20±1 kHz frequency was used. The aim of this study is to evaluate the non-thermal ultrasonic method and its effective factors on the E.coli bacteria of sour cherry. For this purpose, a certain amount of sour cherry fruit was purchased from local markets. First, the fruits were washed, cleaned and cored. The prepared fruits were then dewatered using an electric juicer. In order to separate pulp suspensions and tissue components, the extracted juice was poured into a centrifuge with the speed of 6000 rpm for 20 min. For complete separation of the remaining suspended particles, the transparent portion of the extract was passed through a

Miniaturized and general purpose fiber optic ultrasonic sources

International Nuclear Information System (INIS)

Biagi, E.; Fontani, S.; Masotti, L.; Pieraccini, M.

1997-01-01

Innovative photoacoustic sources for ultrasonic NDE, smart structure, and clinical diagnosis are proposed. The working principle is based on thermal conversion of laser pulses into a metallic film evaporated directly onto the tip of a fiber optic. Unique features of the proposed transducers are very high miniaturization and potential easy embedding in smart structure. Additional advantages, high bedding in smart structure. Additional advantages, high ultrasonic frequency, large and flat bandwidth. All these characteristics make the proposed device an ideal ultrasonic source

Experimental study on combined cold forging process of backward cup extrusion and piercing

Science.gov (United States)

Henry, Robinson; Liewald, Mathias

2018-05-01

A reduction in material usage of cold forged components while maintaining the functional requirements can be achieved using hollow or tubular preforms. These preforms are used to meet lightweight requirements and to decrease production costs of cold formed components. To increase production efficiency in common multi-stage cold forming processes, manufacturing of hollow preforms by combining the processes backward cup extrusion and piercing was established and will be discussed in this paper. Corresponding investigations and experimental studies are reported in this article. The objectives of the experimental investigations have been the detection of significant process parameters, determination of process limits for the combined processes and validation of the numerical investigations. In addition, the general influence concerning surface quality and diameter tolerance of hollow performs are discussed in this paper. The final goal is to summarize a guideline for industrial application, moreover, to transfer the knowledge to industry, as regards what are required part geometries to reduce the number of forming stages as well as tool cost.

Design of fresh food sensory perceptual system for cold chain logistics

Directory of Open Access Journals (Sweden)

Zhang Ying

2018-01-01

Full Text Available According to the present stage low-level information of China's cold chain preservation, designed a kind of fresh food sensory perceptual system for cold chain logistics based on Internet of things. This system highly integrated applied many technologies such as the Internet of things technology, forecasting technology for fruits and vegetables preservation period, RFID and Planar bar code technology, big data and cloud computing technology and so on.Designed as a four-layer structure including sensing layer, network layer, control layer and user layer. The system can implement the real-time temperature and humidity environment parameters monitoring and early warning of the whole cold chain logistics for fresh agricultural products from picking, storage, transportation and processing link. It greatly improved the information level of cold chain circulation in our country and has a strong marketing value.

Enhancement of gama-aminobutyric acid (GABA) and other health-related metabolites in germinated red rice (Oryza sativa L.) by ultrasonication.

Science.gov (United States)

Ding, Junzhou; Ulanov, Alexander V; Dong, Mengyi; Yang, Tewu; Nemzer, Boris V; Xiong, Shanbai; Zhao, Siming; Feng, Hao

2018-01-01

Red rice (Oryza sativa L.) that has a red (reddish brown) bran layer in de-hulled rice is known to contain rich biofunctional components. Germination is an effective technique to improve the nutritional quality, digestibility, and flavor of de-hulled rice. Ultrasonication, a form of physical stimulation, has been documented as a novel approach to improve the nutritional quality of plant-based food. This study was undertaken to test the use of ultrasound to enhance the nutritional value of red rice. Ultrasonication (5min, 16W/L) was applied to rice during soaking or after 66h germination. Changes of metabolites (amino acids, sugars, and organic acids) in red rice treated by ultrasonication were determined using a GC/MS plant primary metabolomics analysis platform. Differential expressed metabolites were identified through multivariate statistical analysis. Results showed that γ-aminobutyric acid (GABA) and riboflavin (vitamin B 2 ) in red rice significantly increased after germination for 72h, and then experienced a further increase after treatment by ultrasound at different stages during germination. The metabolomics analysis showed that some plant metabolites, i.e. GABA, O-phosphoethanolamine, and glucose-6-phosphate were significantly increased after the ultrasonic treatment (VIP>1.5) in comparison with the untreated germinated rice. The findings of this study showed that controlled germination with ultrasonic stress is an effective method to enhance GABA and other health-promoted components in de-hulled rice. Copyright © 2017 Elsevier B.V. All rights reserved.

Diagnostic evaluation of rolling behavior in ball bearings by ultrasonic technique

International Nuclear Information System (INIS)

Wakabayashi, T

2012-01-01

Failures of machines having rotating parts are mostly caused by damage to bearings and there exist increasing demands for detecting damaged bearings at an early stage. However, conventional diagnostic methods, such as measuring temperature and observing vibration, have found difficulties in performing the early detection, so that more advanced diagnosis is necessary. This study therefore applies an ultrasonic technique as an advanced diagnostic method to bearing life tests. Ultrasonic wave pulses (UWP) emitted from a piezoelectric UWP generator can partially reflect from the interfaces of contact zones within the housing and the bearing with regard to the different acoustic impedance between a solid-to-solid contact and a contact dominated by some fluid layers. Hence, the intensity of the resultant UWP echoes can be determined by the real contact area formed at the interfaces. The experimental results of UWP echoes under the different operating conditions have demonstrated that the time intervals between peaks of UWP echoes varied in accordance with the movement of rolling balls and the lubricating phenomena in bearings. This behavior has further suggested the possibility of the early detection of abnormalities in ball bearings by using the variation in UWP echoes.

Deconvolution algorithms applied in ultrasonics; Methodes de deconvolution en echographie ultrasonore

Energy Technology Data Exchange (ETDEWEB)

Perrot, P

1993-12-01

In a complete system of acquisition and processing of ultrasonic signals, it is often necessary at one stage to use some processing tools to get rid of the influence of the different elements of that system. By that means, the final quality of the signals in terms of resolution is improved. There are two main characteristics of ultrasonic signals which make this task difficult. Firstly, the signals generated by transducers are very often non-minimum phase. The classical deconvolution algorithms are unable to deal with such characteristics. Secondly, depending on the medium, the shape of the propagating pulse is evolving. The spatial invariance assumption often used in classical deconvolution algorithms is rarely valid. Many classical algorithms, parametric and non-parametric, have been investigated: the Wiener-type, the adaptive predictive techniques, the Oldenburg technique in the frequency domain, the minimum variance deconvolution. All the algorithms have been firstly tested on simulated data. One specific experimental set-up has also been analysed. Simulated and real data has been produced. This set-up demonstrated the interest in applying deconvolution, in terms of the achieved resolution. (author). 32 figs., 29 refs.

Considerations for ultrasonic testing application for on-orbit NDE

Science.gov (United States)

Koshti, Ajay M.

2015-04-01

The paper addresses some on-orbit nondestructive evaluation (NDE) needs of NASA for International Space Station (ISS). The presentation gives NDE requirements for inspecting suspect damage due to micro-meteoroids and orbital debris (MMOD) impact on the pressure wall of the ISS. This inspection is meant to be conducted from inside of the ISS module. The metallic wall of the module has a fixed wall thickness but also has integral orthogrid ribs for reinforcement. Typically, a single MMOD hit causes localized damage in a small area causing loss of material similar to pitting corrosion, but cracks may be present too. The impact may cause bulging of the wall. Results of the ultrasonic and eddy current demonstration scans on test samples are provided. The ultrasonic technique uses shear wave scans to interrogate the localized damage area from the surrounding undamaged area. The scanning protocol results in multiple scans, each with multiple "vee" paths. A superimposition and mosaic of the three-dimensional ultrasonic data from individual scans is desired to create C-scan images of the damage. This is a new data reduction process which is not currently implemented in state-of-art ultrasonic instruments. Results of ultrasonic scans on the simulated MMOD damage test plates are provided. The individual C-scans are superimposed manually creating mosaic of the inspection. The resulting image is compared with visibly detected damage boundaries, X-ray images, and localized ultrasonic and eddy current scans for locating crack tips to assess effectiveness of the ultrasonic scanning. The paper also discusses developments needed in improving ergonomics of the ultrasonic testing for on-orbit applications.

Process Stability of Ultrasonic-Wave-Assisted Gas Metal Arc Welding

Science.gov (United States)

Fan, Chenglei; Xie, Weifeng; Yang, Chunli; Lin, Sanbao; Fan, Yangyang

2017-10-01

As a newly developed arc welding method, ultrasonic-wave-assisted arc welding successfully introduced power ultrasound into the arc and weld pool, during which the ultrasonic acts on the top of the arc in the coaxial alignment direction. The advanced process for molten metals can be realized by using an additional ultrasonic field. Compared with the conventional gas metal arc welding (GMAW), the welding arc is compressed, the droplet size is decreased, and the droplet transfer frequency is increased significantly in ultrasonic-wave-assisted GMAW (U-GMAW). However, the stability of the metal transfer has deep influence on the welding quality equally, and the ultrasonic wave effect on the stability of the metal transfer is a phenomenon that is not completely understood. In this article, the stabilities of the short-circuiting transfer process and globular transfer process are studied systematically, and the effect of ultrasonic wave on the metal transfer is analyzed further. The transfer frequency and process stability of the U-GMAW process are much higher than those of the conventional GMAW. Analytical results show that the additional ultrasonic wave is helpful for improving welding stability.

Study on the development of ultrasonic gas flowmeter

International Nuclear Information System (INIS)

Hwang, Won Ho; Park, Sang Gug; Yang, Kyu Hong; Jhang, Kyung Young

2001-01-01

Ultrasonic flowmeters have more advantages than the conventional method using pressure-difference. In these reasons, many advanced nations are already selling the commercial model. In RIST, we have been developed ultrasonic gas flow meter for the localization since a project was been contracted with POSCO in 1997. This paper describes a new ultrasonic gas flowmeter. This ultrasonic gas flowmeter is developed for accurate measurement of gases in a harsh environmental conditions. It is especially suited for measuring LDG, COG, BFG gases produced in iron and steel making process. In this study, we had developed the commercial model about the first tested model and applied a completed system to the POSCO gas line. Its performance has already well been proven by extensive field tests for several months in POSCO, iron and steel making company

Method of noncontacting ultrasonic process monitoring

Science.gov (United States)

Garcia, Gabriel V.; Walter, John B.; Telschow, Kenneth L.

1992-01-01

A method of monitoring a material during processing comprising the steps of (a) shining a detection light on the surface of a material; (b) generating ultrasonic waves at the surface of the material to cause a change in frequency of the detection light; (c) detecting a change in the frequency of the detection light at the surface of the material; (d) detecting said ultrasonic waves at the surface point of detection of the material; (e) measuring a change in the time elapsed from generating the ultrasonic waves at the surface of the material and return to the surface point of detection of the material, to determine the transit time; and (f) comparing the transit time to predetermined values to determine properties such as, density and the elastic quality of the material.

Fast synthesize ZnO quantum dots via ultrasonic method.

Science.gov (United States)

Yang, Weimin; Zhang, Bing; Ding, Nan; Ding, Wenhao; Wang, Lixi; Yu, Mingxun; Zhang, Qitu

2016-05-01

Green emission ZnO quantum dots were synthesized by an ultrasonic sol-gel method. The ZnO quantum dots were synthesized in various ultrasonic temperature and time. Photoluminescence properties of these ZnO quantum dots were measured. Time-resolved photoluminescence decay spectra were also taken to discover the change of defects amount during the reaction. Both ultrasonic temperature and time could affect the type and amount of defects in ZnO quantum dots. Total defects of ZnO quantum dots decreased with the increasing of ultrasonic temperature and time. The dangling bonds defects disappeared faster than the optical defects. Types of optical defects first changed from oxygen interstitial defects to oxygen vacancy and zinc interstitial defects. Then transformed back to oxygen interstitial defects again. The sizes of ZnO quantum dots would be controlled by both ultrasonic temperature and time as well. That is, with the increasing of ultrasonic temperature and time, the sizes of ZnO quantum dots first decreased then increased. Moreover, concentrated raw materials solution brought larger sizes and more optical defects of ZnO quantum dots. Copyright © 2015 Elsevier B.V. All rights reserved.

Piezoelectric Nanotube Array for Broadband High-Frequency Ultrasonic Transducer.

Science.gov (United States)

Liew, Weng Heng; Yao, Kui; Chen, Shuting; Tay, Francis Eng Hock

2018-03-01

Piezoelectric materials are vital in determining ultrasonic transducer and imaging performance as they offer the function for conversion between mechanical and electrical energy. Ultrasonic transducers with high-frequency operation suffer from performance degradation and fabrication difficulty of the demanded piezoelectric materials. Hence, we propose 1-D polymeric piezoelectric nanostructure with controlled nanoscale features to overcome the technical limitations of high-frequency ultrasonic transducers. For the first time, we demonstrate the integration of a well-aligned piezoelectric nanotube array to produce a high-frequency ultrasonic transducer with outstanding performance. We find that nanoconfinement-induced polarization orientation and unique nanotube structure lead to significantly improved piezoelectric and ultrasonic transducing performance over the conventional piezoelectric thin film. A large bandwidth, 126% (-6 dB), is achieved at high center frequency, 108 MHz. Transmission sensitivity of nanotube array is found to be 46% higher than that of the monolithic thin film transducer attributed to the improved electromechanical coupling effectiveness and impedance match. We further demonstrate high-resolution scanning, ultrasonic imaging, and photoacoustic imaging using the obtained nanotube array transducers, which is valuable for biomedical imaging applications in the future.

[Destruction of synovial pannus of antigen-induced arthritis by ultrasonic cavitation in rabbits].

Science.gov (United States)

Zhang, Ling-yan; Qiu, Li; Wang, Lei; Lin, Ling; Wen, Xiao-rong

2011-11-01

To optimize the conditions of ultrasonic irradiation and microbubble of ultrasound cavitation on destruction of synovial pannus of antigen-induced arthritis (AIA) in rabbits. Antigen-induced arthritis was successfully induced on bilateral knee joints of 85 rabbits. Each 10 AIA rabbits were divided into two groups to compare various peak negative pressures, different ultrasonic pulse durations, various pulse repetition frequencies, different irradiance duration, different dosages of microbubble contrast agents, different ultrasonic irradiance times. With intravenous infusion of Sonovue to the rabbits, ultrasonic irradiance was performed on the right knee joint using the above condition of ultrasound cavitation. At the day 1 after ultrasonic irradiance, MRI and pathological examination were employed to evaluate the optimal conditions. The optimal parameters and conditions for ultrasonic irradiance included intermittent ultrasonic application (in 6 s intervals), 0.6 mL/kg of microbubble contrast agent, 4.6 MPa of ultrasonic peak negative pressure, 100 cycles of pulse duration, 50 Hz of pulse repetition frequency, 5 min of ultrasonic duration, 0.6 mL/kg of dosages of microbubble contrast agents and multi-sessional ultrasonic irradiance. After the ultrasonic irradiance, the thickness of right knee synovium measured by MRI was thinner than that of left knee and synovial necrosis was confirmed by the pathological finding. Under optimal ultrasonic irradiation and microbubble conditions, ultrasonic cavitation could destroy synovial pannus of AIA in rabbits.

P-Scan provides accuracy and repeatability in ultrasonics

International Nuclear Information System (INIS)

Keys, R.L.

1987-01-01

The P-Scan (Projection image scanning technique) is an automated ultrasonic inspection technique, developed to overcome the problems with accuracy and repeatability experienced with manual ultrasonic systems. The equipment and its applications are described. (author)

Ultrasonic experiment on hydrate formation of a synthesis gas

Energy Technology Data Exchange (ETDEWEB)

Sun, Shicai; Fan, Shuanshi; Liang, Deqing; Zhang, Junshe; Feng, Ziping

2005-07-01

The effect of ultrasonic on the induction time and formation rate of natural gas hydrates was investigated in a stainless steel cell in this study. The results show that the induction time with ultrasonic was about 1/6 of that without ultrasonic and only about 1/10 if rehydration after decomposition in water-gas system. In sodium dodecyl sulfate (SDS) solution-gas system, the critical micellar concentration (CMC) was not identified with ultrasonic. The formation rate and storage capacity of hydrate increased with increasing SDS concentration at a range of 0 to 800ppm. However, the increase was insignificant as the SDS concentration increased from 600 to 800ppm, (Author)

Selective Bioparticle Retention and Characterization in a Chip-Integrated Confocal Ultrasonic Cavity

DEFF Research Database (Denmark)

Svennebring, J.; Manneberg, O.; Skafte-Pedersen, Peder

2009-01-01

We demonstrate selective retention and positioning of cells or other bioparticles by ultrasonic manipulation in a microfluidic expansion chamber during microfluidic perfusion. The chamber is designed as a confocal ultrasonic resonator for maximum confinement of the ultrasonic force field at the c......We demonstrate selective retention and positioning of cells or other bioparticles by ultrasonic manipulation in a microfluidic expansion chamber during microfluidic perfusion. The chamber is designed as a confocal ultrasonic resonator for maximum confinement of the ultrasonic force field...... sample feeding, a set of several manipulation functions performed in series is demonstrated: sample bypass-injection-aggregation and retention-positioning. Finally, we demonstrate transillumination microscopy imaging Of Ultrasonically trapped COS-7 cell aggregates. Biotechnol. Bioeng. 2009;103: 323-328....

Defect detection and sizing in ultrasonic imaging

International Nuclear Information System (INIS)

Moysan, J.; Benoist, P.; Chapuis, N.; Magnin, I.

1991-01-01

This paper introduces imaging processing developed with the SPARTACUS system in the field of ultrasonic testing. The aim of the imaging processing is to detect and to separate defects echoes from background noise. Image segmentation and particularities of ultrasonic images are the base of studied methods. 4 figs.; 6 refs [fr

Reproducibility problems of in-service ultrasonic testing results

International Nuclear Information System (INIS)

Honcu, E.

1974-01-01

The reproducibility of the results of ultrasonic testing is the basic precondition for its successful application in in-service inspection of changes in the quality of components of nuclear power installations. The results of periodic ultrasonic inspections are not satisfactory from the point of view of reproducibility. Regardless, the ultrasonic pulse-type method is suitable for evaluating the quality of most components of nuclear installations and often the sole method which may be recommended for inspection with regard to its technical and economic aspects. (J.B.)

Further Investigations on Simultaneous Ultrasonic Coal Flotation

Directory of Open Access Journals (Sweden)

Safak Gokhan Ozkan

2017-09-01

Full Text Available This study investigates the flotation performance of a representative hard coal slime sample (d80 particle size of minus 0.2 mm obtained from the Prosper-Haniel coal preparation plant located in Bottrop, Germany. Flotation was carried out with a newly designed flotation cell refurbished from an old ultrasonic cleaning bath (2.5 L volume equipped with a single frequency (35 kHz and two different power levels (80–160 W and a sub-aeration-type flotation machine operating at a stable impeller speed (1200 rpm and air rate (2.5 L/min. The reagent combination for conventional and simultaneous ultrasonic coal flotation tests was Ekofol-440 at variable dosages (40–300 g/t with controlling water temperature (20–25 °C at natural pH (6.5–7.0. The batch coal flotation results were analyzed by comparing the combustible recovery (% and separation efficiency (% values, taking mass yield and ash concentrations of the froths and tailings into account. It was found that simultaneous ultrasonic coal flotation increased yield and recovery values of the floated products with lower ash values than the conventional flotation despite using similar reagent dosages. Furthermore, particle size distribution of the ultrasonically treated and untreated coals was measured. Finely distributed coal particles seemed to be agglomerated during the ultrasonic treatment, while ash-forming slimes were removed by hydrodynamic cavitation.

Development and application of the ultrasonic technologies in nuclear engineering

International Nuclear Information System (INIS)

Lebedev, Nikolay; Krasilnikov, Dmitry; Vasiliev, Albert; Dubinin, Gennady; Yurmanov, Viktor

2012-09-01

Efficiency of some traditional chemical technologies in different areas could be significantly increased by adding ultrasonic treatment. For example, ultrasonic treatment was found to improve make-up water systems, decontamination procedures, etc. Improvement of traditional chemical technologies with implementation of ultrasonic treatment has allowed to significantly reducing water waste, including harmful species and radioactive products. The report shows the examples of the recent ultrasonic technology development and application in Russian nuclear engineering. They are as follows: - Preliminary cleaning of surfaces of in-pile parts (e.g. control sensors) prior to their assemblage and welding - Decontamination of grounds and metal surfaces of components with a complex structure -Decrease in sliding friction between fuel rods and grids during VVER reactor fuel assembly manufacturing -Removal of deposits from reactor fuel surfaces in VVER-440s -Increasing the density and strength of pressed sintered items while making fuel pellets and fuel elements, especially mixed-oxide fuel Surface cleanness is very important for the fuel assembly manufacturing, especially prior to welding. An ultrasonic technology for surface cleaning (from graphite and other lubricants, oxides etc.) was developed and implemented. The ultrasonic cleaning is applicable to the parts having both simple shape and different holes. Ultrasonic technology has allowed to improve the surface quality and environmental safety. Ultrasonic treatment appears to be expedient to intensify the chemical decontamination of solid radioactive waste from grounds of different fractions to metallic components. Ultrasonic treatment reduces the decontamination process duration up to 100 times as much. Excellent decontamination factor was received even for the ground fractions below 1 mm. It should be noted that alternative decontamination techniques (e.g. hydraulic separation) are poorly applicable for such ground

An inverse method for crack characterization from ultrasonic B-Scan images

International Nuclear Information System (INIS)

Faur, M.; Roy, O.; Benoist, PH.; Morisseau, PH.

1996-01-01

Concern has been expressed about the capabilities of performing non destructive evaluation (NDE) of flaws located near to the outer surface in nuclear pressurized water reactor (PWR) vessels. The ultrasonic examination of PWR is accomplished from the inside with ultrasonic focused transducers working in the pulse echo mode. By recording the echoes as a function of time, the Ascan representation may be obtained. Many ultrasonic flaw detectors used for NDE are based on the simple Ascan concept involving measuring a time interval called 'time of flight'. By combining the Ascan concept synchronized transducer scanning, one can produce Bscan images that are two dimensional descriptions of the flaw interaction with the ultrasonic field. In the following, the flaw is assumed to be an axially oriented crack (the most serious flaw to be found in a pressurized component). In the case of the outer surface cracks (OSC's), analyzing and interpreting ultrasonic Ascan images become difficult because of the various reflections of the ultrasonic beam on the crack and on the outer surface (the so-called corner effect). Methods for automatic interpretation of ultrasonic experimental data are currently under investigation. In this paper, we present an inverse method for determining the geometrical characteristics of OSC's from ultrasonic Bscan images. The direct model used for the inversion procedure predicts synthetic Bscan images of ultrasonic examination of blocks containing planar defects interrogated by focused probes. (authors)

Ultrasonic calibration assembly

International Nuclear Information System (INIS)

1981-01-01

Ultrasonic transducers for in-service inspection of nuclear reactor vessels have several problems associated with them which this invention seeks to overcome. The first is that of calibration or referencing a zero start point for the vertical axis of transducer movement to locate a weld defect. The second is that of verifying the positioning (vertically or at a predetermined angle). Thirdly there is the problem of ascertaining the speed per unit distance in the operating medium of the transducer beam prior to the actual inspection. The apparatus described is a calibration assembly which includes a fixed, generally spherical body having a surface for reflecting an ultrasonic beam from one of the transducers which can be moved until the reflection from the spherical body is the highest amplitude return signal indicating radial alignment from the body. (U.K.)

Very high temperature ultrasonic thermometer

International Nuclear Information System (INIS)

Jorzik, E.

1983-01-01

An ultrasonic thermometer comprises an electric pulse transducer head, a pulse transmission line, a notched sensor wire attached to and extending along the axis of said transmission line and a sheath enclosing the transmission line and the sensor wire, a portion of the interior face of the sheath being covered by a stuffing material along at least the length of the notched part of the sensor wire, such that contact between the sensor wire and the stuffing material does not substantially give rise to reflection of an ultrasonic pulse at the point of contact. (author)

Ultrasonically assisted drilling of rocks

Science.gov (United States)

Mikhailova, N. V.; Onawumi, P. Y.; Roy, A.; Silberschmidt, V. V.

2018-05-01

Conventional drilling of rocks can generate significant damage in the drilled material; a material layer is often split off a back surface of a sample during drilling, negatively affecting its strength. To improve finish quality, ultrasonically assisted drilling (UAD) was employed in two rocks - sandstone and marble. Damage areas in both materials were reduced in UAD when compared to conventional drilling. Reductions in a thrust force and a torque reduction were observed only for UAD in marble; ultrasonic assistance in sandstone drilling did not result in improvements in this regard.

Ultrasonic control of ceramic membrane fouling by particles: effect of ultrasonic factors.

Science.gov (United States)

Chen, Dong; Weavers, Linda K; Walker, Harold W

2006-07-01

Ultrasound at 20 kHz was applied to a cross-flow ultrafiltration system with gamma-alumina membranes in the presence of colloidal silica particles to systematically investigate how ultrasonic factors affect membrane cleaning. Based on imaging of the ultrasonic cavitation region, optimal cleaning occurred when the membrane was outside but close to the cavitation region. Increasing the filtration pressure increased the compressive forces driving cavitation collapse and resulted in fewer cavitation bubbles absorbing and scattering sound waves and increasing sound wave penetration. However, an increased filtration pressure also resulted in greater permeation drag, and subsequently less improvement in permeate flux compared to low filtration pressure. Finally, pulsed ultrasound with short pulse intervals resulted in permeate flux improvement close to that of continuous sonication.

C-Scan Performance Test of Under-Sodium ultrasonic Waveguide Sensor in Sodium

International Nuclear Information System (INIS)

Joo, Young Sang; Bae, Jin Ho; Kim, Jong Bum

2011-01-01

Reactor core and in-vessel structures of a sodium-cooled fast (SFR) are submerged in opaque liquid sodium in the reactor vessel. The ultrasonic inspection techniques should be applied for observing the in-vessel structures under hot liquid sodium. Ultrasonic sensors such as immersion sensors and rod-type waveguide sensors have developed in order to apply under-sodium viewing of the in-vessel structures of SFR. Recently the novel plate-type ultrasonic waveguide sensor has been developed for the versatile application of under-sodium viewing in SFR. In previous studies, the ultrasonic waveguide sensor module was designed and manufactured, and the feasibility study of the ultrasonic waveguide sensor was performed. To improve the performance of the ultrasonic waveguide sensor in the under-sodium application, a new concept of ultrasonic waveguide sensors with a Be coated SS304 plate is suggested for the effective generation of a leaky wave in liquid sodium and the non-dispersive propagation of A 0 -mode Lamb wave in an ultrasonic waveguide sensor. In this study, the C-scan performance of the under-sodium ultrasonic waveguide sensor in sodium has been investigated by the experimental test in sodium. The under-sodium ultrasonic waveguide sensor and the sodium test facility with a glove box system and a sodium tank are designed and manufactured to carry out the performance test of under-sodium ultrasonic waveguide sensor in sodium environment condition

Liquid ultrasonic flow meters for crude oil measurement

Energy Technology Data Exchange (ETDEWEB)

Kalivoda, Raymond J.; Lunde, Per

2005-07-01

Liquid ultrasonic flow meters (LUFMs) are gaining popularity for the accurate measurement of petroleum products. In North America the first edition of the API standard ''Measurement of liquid hydrocarbons by ultrasonic flow meters using transit time technology'' was issued in February 2005. It addresses both refined petroleum products and crude oil applications. Its field of application is mainly custody transfer applications but it does provide general guidelines for the installation and operation of LUFM's other applications such as allocation, check meters and leak detection. As with all new technologies performance claims are at times exaggerated or misunderstood and application knowledge is limited. Since ultrasonic meters have no moving parts they appear to have fewer limitations than other liquid flow meters. Liquids ultrasonic flow meters, like turbine meters, are sensitive to fluid properties. It is increasingly more difficult to apply on high viscosity products then on lighter hydrocarbon products. Therefore application data or experience on the measurement of refined or light crude oil may not necessarily be transferred to measuring medium to heavy crude oils. Before better and more quantitative knowledge is available on how LUFMs react on different fluids, the arguments advocating reduced need for in-situ proving and increased dependency on laboratory flow calibration (e.g. using water instead of hydrocarbons) may be questionable. The present paper explores the accurate measurement of crude oil with liquid ultrasonic meters. It defines the unique characteristics of the different API grades of crude oils and how they can affect the accuracy of the liquid ultrasonic measurement. Flow testing results using a new LUFM design are discussed. The paper is intended to provide increased insight into the potentials and limitations of crude oil measurement using ultrasonic flow meters. (author) (tk)

A study on Computer-controlled Ultrasonic Scanning Device

International Nuclear Information System (INIS)

Huh, H.; Park, C. S.; Hong, S. S.; Park, J. H.

1989-01-01

Since the nuclear power plants in Korea have been operated in 1979, the nondestructive testing (NDT) of pressure vessels and/or piping welds plays an important role for maintaining the safety and integrity of the plants. Ultrasonic method is superior to the other NDT method in the viewpoint of the detectability of small flaw and accuracy to determine the locations, sizes, orientations, and shapes. As the service time of the nuclear power plants is increased, the radiation level from the components is getting higher. In order to get more quantitative and reliable results and secure the inspector from the exposure to high radiation level, automation of the ultrasonic equipment has been one of the important research and development(R and D) subject. In this research, it was attempted to visualize the shape of flaws presented inside the specimen using a Modified C-Scan technique. In order to develop Modified C-Scan technique, an automatic ultrasonic scanner and a module to control the scanner were designed and fabricated. IBM-PC/XT was interfaced to the module to control the scanner. Analog signals from the SONIC MARK II were digitized by Analog-Digital Converter(ADC 0800) for Modified C-Scan display. A computer program has been developed and has capability of automatic data acquisition and processing from the digital data, which consist of maximum amplitudes in each gate range and locations. The data from Modified C-Scan results was compared with shape from artificial defects using the developed system. Focal length of focused transducer was measured. The automatic ultrasonic equipment developed through this study is essential for more accurate, reliable, and repeatable ultrasonic experiments. If the scanner are modified to meet to appropriate purposes, it can be applied to automation of ultrasonic examination of nuclear power plants and helpful to the research on ultrasonic characterization of the materials

Chemical coloring on stainless steel by ultrasonic irradiation.

Science.gov (United States)

Cheng, Zuohui; Xue, Yongqiang; Ju, Hongbin

2018-01-01

To solve the problems of high temperature and non-uniformity of coloring on stainless steel, a new chemical coloring process, applying ultrasonic irradiation to the traditional chemical coloring process, was developed in this paper. The effects of ultrasonic frequency and power density (sound intensity) on chemical coloring on stainless steel were studied. The uniformity of morphology and colors was observed with the help of polarizing microscope and scanning electron microscopy (SEM), and the surface compositions were characterized by X-ray photoelectric spectroscopy (XPS), meanwhile, the wear resistance and the corrosion resistance were investigated, and the effect mechanism of ultrasonic irradiation on chemical coloring was discussed. These results show that in the process of chemical coloring on stainless steel by ultrasonic irradiation, the film composition is the same as the traditional chemical coloring, and this method can significantly enhance the uniformity, the wear and corrosion resistances of the color film and accelerate the coloring rate which makes the coloring temperature reduced to 40°C. The effects of ultrasonic irradiation on the chemical coloring can be attributed to the coloring rate accelerated and the coloring temperature reduced by thermal-effect, the uniformity of coloring film improved by dispersion-effect, and the wear and corrosion resistances of coloring film enhanced by cavitation-effect. Ultrasonic irradiation not only has an extensive application prospect for chemical coloring on stainless steel but also provides an valuable reference for other chemical coloring. Copyright © 2017 Elsevier B.V. All rights reserved.

Simulation of the Two-Phase Liquid – Gas Flow through Ultrasonic Transceivers Application in Ultrasonic Tomography

Directory of Open Access Journals (Sweden)

Zulkarnay Zakaria

2010-01-01

Full Text Available In this paper, ultrasonic transmission mode tomography was used to visualize the two phase liquid/gas flow in a pipe/vessel. The sensing element consists of 8, 16 and 32 units ultrasonic transceivers were used to cover the pipe cross-section at different time. The motivation of this paper is to analyze the optimum numbers of transceivers which can give the best performance in providing better image of the two phase liquid/gas flow. This paper also details the development of the system including the ultrasonic transduction circuits, the electronic measurement circuits, the data acquisition system and the image reconstruction techniques. Ten conditions of liquid-gas flow have been simulated. The system was found capable of visualizing the internal characteristics and provides the concentration profile for the corresponding liquid and gas phases while the 32 transceivers has provided the best image for the ten conditions applied.

Method and system having ultrasonic sensor movable by translation device for ultrasonic profiling of weld samples

Science.gov (United States)

Panyard, James; Potter, Timothy; Charron, William; Hopkins, Deborah; Reverdy, Frederic

2010-04-06

A system for ultrasonic profiling of a weld sample includes a carriage movable in opposite first and second directions. An ultrasonic sensor is coupled to the carriage to move over the sample as the carriage moves. An encoder determines the position of the carriage to determine the position of the sensor. A spring is connected at one end of the carriage. Upon the carriage being moved in the first direction toward the spring such that the carriage and the sensor are at a beginning position and the spring is compressed the spring decompresses to push the carriage back along the second direction to move the carriage and the sensor from the beginning position to an ending position. The encoder triggers the sensor to take the ultrasonic measurements of the sample when the sensor is at predetermined positions while the sensor moves over the sample between the beginning and positions.

Experiences in using ultrasonic holography with numerical and optical reconstruction

International Nuclear Information System (INIS)

Schmitz, V.; Wosnitza, M.

1978-01-01

At present, ultrasonic holography can resolve and image faults of 1 mm and more and with distances of one ultrasonic wavelength. The main field of application is for thick-walled structural components. Depending on the expected orientation, test probe arrangements as in standard ultrasonic testing are chosen. (orig./RW) [de

Improvement of solar ethanol distillation using ultrasonic waves

Directory of Open Access Journals (Sweden)

Jaruwat Jareanjit

2016-08-01

Full Text Available This report presents a study on the use of ultrasonic waves in solar ethanol distillation to investigate the performance of ultrasonic waves at a frequency of 30 kHz and at 100 Watts that were installed in the inlet area of a 10-litre distillation tank. Based on the non-continuous distillation process (batch distillation, the experiment demonstrated that using ultrasonic waves in solar ethanol distillation caused the average concentration of hourly distilled ethanol to be higher than that of a normal system (solar ethanol distillation without ultrasonic wave at the same or higher distillation rate and hourly distillation volume. The ultrasonic wave was able to enhance the separation of ethanol from the solution (water-ethanol mixture through solar distillation. The amount of pure ethanol product from each distilled batch was clearly larger than the amount of product obtained from a normal system when the initial concentration of ethanol was lower than 50%v/v (% by volume, where an average of approximately 40% and 20% are obtained for an initial ethanol concentration of 10%v/v and 30%v/v, respectively. Furthermore, the distillation rate varied based on the solar radiation value.

Failed fuel rod detection method by ultrasonic wave

International Nuclear Information System (INIS)

Takamatsu, Masatoshi; Muraoka, Shoichi; Ono, Yukio; Yasojima, Yujiro.

1990-01-01

Ultrasonic wave signals sent from an ultrasonic receiving element are supplied to an evaluation circuit by way of a gate. A table for gate opening and closing timings at the detecting position in each of the fuel rods in a fuel assembly is stored in a memory. A fuel rod is placed between an ultrasonic transmitting element and the receiving element to determine the positions of the transmitting element and the receiving element by positional sensors. The opening and closing timings at the positions corresponding to the result of the detection are read out from the table, and the gates are opened and closed by the timing. This can introduce the ultrasonic wave signals transmitted through a control rod always to the evaluation circuit passing through the gate. Accordingly, the state of failure of the fuel rod can be detected accurately. (I.N.)

Ultrasonic weld testing.

Science.gov (United States)

1970-12-01

The study was broken down into two phases. Phase I consisted of a laboratory investigation of test specimens to determine the reliability of the ultrasonic equipment and testing procedure. Phase II was a field study where the knowledge, skills and ab...

System and technique for ultrasonic determination of degree of cooking

Energy Technology Data Exchange (ETDEWEB)

Bond, Leonard J [Richland, WA; Diaz, Aaron A [W. Richland, WA; Judd, Kayte M [Richland, WA; Pappas, Richard A [Richland, WA; Cliff, William C [Richland, WA; Pfund, David M [Richland, WA; Morgen, Gerald P [Kennewick, WA

2007-03-20

A method and apparatus are described for determining the doneness of food during a cooking process. Ultrasonic signal are passed through the food during cooking. The change in transmission characteristics of the ultrasonic signal during the cooking process is measured to determine the point at which the food has been cooked to the proper level. In one aspect, a heated fluid cooks the food, and the transmission characteristics along a fluid-only ultrasonic path provides a reference for comparison with the transmission characteristics for a food-fluid ultrasonic path.

Effect of acoustic softening on the thermal-mechanical process of ultrasonic welding.

Science.gov (United States)

Chen, Kunkun; Zhang, Yansong; Wang, Hongze

2017-03-01

Application of ultrasonic energy can reduce the static stress necessary for plastic deformation of metallic materials to reduce forming load and energy, namely acoustic softening effect (ASE). Ultrasonic welding (USW) is a rapid joining process utilizing ultrasonic energy to form a solid state joint between two or more pieces of metals. Quantitative characterization of ASE and its influence on specimen deformation and heat generation is essential to clarify the thermal-mechanical process of ultrasonic welding. In the present work, experiments were set up to found out mechanical behavior of copper and aluminum under combined effect of compression force and ultrasonic energy. Constitutive model was proposed and numerical implemented in finite element model of ultrasonic welding. Thermal-mechanical analysis was put forward to explore the effect of ultrasonic energy on the welding process quantitatively. Conclusions can be drawn that ASE increases structural deformation significantly, which is beneficial for joint formation. Meanwhile, heat generation from both frictional work and plastic deformation is slightly influenced by ASE. Based on the proposed model, relationship between ultrasonic energy and thermal-mechanical behavior of structure during ultrasonic welding was constructed. Copyright © 2016 Elsevier B.V. All rights reserved.

Ethylene and cold participate in the regulation of LeCBF1 gene expression in postharvest tomato fruits.

Science.gov (United States)

Zhao, Danying; Shen, Lin; Fan, Bei; Yu, Mengmeng; Zheng, Yang; Lv, Shengnan; Sheng, Jiping

2009-10-20

C-repeat/dehydration-responsive element binding factor (CBF) is a transcription factor regulating cold response in plants, of which little is known in fruits. We showed a double-peak expression pattern of Lycopersicon esculentum putative transcriptional activator CBF1 (LeCBF1) in mature green fruit. The peaks appeared at 2 and 16 h after subjection to cold storage (2 degrees C). The second peak was coincident with, and thus caused by a peak in endogenous ethylene production. We showed that LeCBF1 expression was regulated by exogenous ethylene and 1-methylcyclopropene, and was not expressed without cold induction. LeCBF1 expression was different in the five maturation stages of fruits, but expression peaked at 2 h at all stages.

An ultrasonic waveguide for nuclear power plants

International Nuclear Information System (INIS)

Watkins, R.D.; Gillespie, A.B.; Deighton, M.O.; Pike, R.B.

1983-01-01

The value of ultrasonic techniques in nuclear plants is well established. However, in most cases nuclear power plants present an extremely hostile environment for an ultrasonic transducer. The paper presents a novel technique for introducing an ultrasound into hostile liquid environments using a new form of ultrasonic waveguide. Using this approach, a standard transducer arrangement is sited in a hospitable area and conveys the ultrasound along the guide to the required beam-emission collection position. The design of a single-mode ultrasonic waveguide is described. The ultrasound is conveyed along a stainless steel strip of rectangular cross-section. The transference of energy between the strip and the liquid is achieved through a highly efficient mode-conversion process. This process overcomes the usual problems of mis-match of acoustic impedances of stainless steel and liquids, and also produces a highly collimated beam of ultrasound. Tests of a 10-m-long waveguide using these techniques are described, achieving signal-to-noise ratios in the region of 40 dB. (author)

Wear reduction through piezoelectrically-assisted ultrasonic lubrication

International Nuclear Information System (INIS)

Dong, Sheng; J Dapino, Marcelo

2014-01-01

Traditional lubricants are undesirable in harsh aerospace environments and certain automotive applications. Ultrasonic vibrations can be used to reduce and modulate the effective friction coefficient between two sliding surfaces. This paper investigates the relationship between friction force reduction and wear reduction in ultrasonically lubricated surfaces. A pin-on-disc tribometer is modified through the addition of a piezoelectric transducer which vibrates the pin at 22 kHz in the direction perpendicular to the rotating disc surface. Friction and wear metrics including volume loss, surface roughness, friction forces and apparent stick-slip effects are measured without and with ultrasonic vibrations at three different sliding velocities. SEM imaging and 3D profilometry are used to characterize the wear surfaces and guide model development. Over the range of speeds considered, ultrasonic vibrations reduce the effective friction force up to 62% along with a wear reduction of up to 49%. A simple cube model previously developed to quantify friction force reduction is implemented which describes wear reduction within 15% of the experimental data. (paper)

Cell and band structures in cold rolled polycrystalline copper

DEFF Research Database (Denmark)

Ananthan, V.S.; Leffers, Torben; Hansen, Niels

1991-01-01

dislocation walls (DDWs) and cells develop during the initial stages of cold rolling. Grains having a high density of DDWs are described as high wall density (HWD) structures, and grains having a low density of DDWs are described as low wall density (LWD) structures. These structures are characterised by cell...

Dog-Bone Horns for Piezoelectric Ultrasonic/Sonic Actuators

Science.gov (United States)

Sherrit, Stewart; Bar-Cohen, Yoseph; Chang, Zensheu; Bao, Xiaoqi

2007-01-01

A shape reminiscent of a dog bone has been found to be superior to other shapes for mechanical-amplification horns that are components of piezoelectrically driven actuators used in a series of related devices denoted generally as ultrasonic/sonic drill/corers (USDCs). The first of these devices was reported in Ultrasonic/Sonic Drill/Corers With Integrated Sensors (NPO-20856), NASA Tech Briefs, Vol. 25, No. 1 (January 2001), page 38. The dog-bone shape was conceived especially for use in a more recent device in the series, denoted an ultrasonic/ sonic gopher, that was described in Ultrasonic/Sonic Mechanisms for Drilling and Coring (NPO-30291), NASA Tech Briefs, Vol. 27, No. 9 (September 2003), page 65. The figure shows an example of a dog-bone-shaped horn and other components of an ultrasonic gopher. Prerequisite to a meaningful description of this development is an unavoidably lengthy recapitulation of the principle of operation of a USDC and, more specifically, of the ultrasonic/sonic gopher as described previously in NASA Tech Briefs. The ultrasonic actuator includes a stack of piezoelectric rings, the horn, a metal backing, and a bolt that connects the aforementioned parts and provides compressive pre-strain to the piezoelectric stack to prevent breakage of the rings during extension. The stack of piezoelectric rings is excited at the resonance frequency of the overall ultrasonic actuator. Through mechanical amplification by the horn, the displacement in the ultrasonic vibration reaches tens of microns at the tip of the horn. The horn hammers an object that is denoted the free mass because it is free to move longitudinally over a limited distance between hard stops: The free mass bounces back and forth between the ultrasonic horn and a tool bit (a drill bit or a corer). Because the longitudinal speed of the free mass is smaller than the longitudinal speed of vibration of the tip of the horn, contact between the free mass and the horn tip usually occurs at a

High quantum yield ZnO quantum dots synthesizing via an ultrasonication microreactor method.

Science.gov (United States)

Yang, Weimin; Yang, Huafang; Ding, Wenhao; Zhang, Bing; Zhang, Le; Wang, Lixi; Yu, Mingxun; Zhang, Qitu

2016-11-01

Green emission ZnO quantum dots were synthesized by an ultrasonic microreactor. Ultrasonic radiation brought bubbles through ultrasonic cavitation. These bubbles built microreactor inside the microreactor. The photoluminescence properties of ZnO quantum dots synthesized with different flow rate, ultrasonic power and temperature were discussed. Flow rate, ultrasonic power and temperature would influence the type and quantity of defects in ZnO quantum dots. The sizes of ZnO quantum dots would be controlled by those conditions as well. Flow rate affected the reaction time. With the increasing of flow rate, the sizes of ZnO quantum dots decreased and the quantum yields first increased then decreased. Ultrasonic power changed the ultrasonic cavitation intensity, which affected the reaction energy and the separation of the solution. With the increasing of ultrasonic power, sizes of ZnO quantum dots first decreased then increased, while the quantum yields kept increasing. The effect of ultrasonic temperature on the photoluminescence properties of ZnO quantum dots was influenced by the flow rate. Different flow rate related to opposite changing trend. Moreover, the quantum yields of ZnO QDs synthesized by ultrasonic microreactor could reach 64.7%, which is higher than those synthesized only under ultrasonic radiation or only by microreactor. Copyright © 2016 Elsevier B.V. All rights reserved.

Wavelet Analysis of Ultrasonic Echo Waveform and Application to Nondestructive Evaluation

International Nuclear Information System (INIS)

Park, Ik Keun; Park, Un Su; Ahn, Hyung Keun; Kwun, Sook In; Byeon, Jai Won

2000-01-01

Recently, advanced signal analysis which is called 'time-frequency analysis' has been used widely in nondestructive evaluation applications. Wavelet transform(WT) and Wigner Distribution are the most advanced techniques for processing signals with time-varying spectra. Wavelet analysis method is an attractive technique for evaluation of material characterization nondestructively. Wavelet transform is applied to the time-frequency analysis of ultrasonic echo waveform obtained by an ultrasonic pulse-echo technique. In this study, the feasibility of noise suppression of ultrasonic flaw signal and frequency-dependent ultrasonic group velocity and attenuation coefficient using wavelet analysis of ultrasonic echo waveform have been verified experimentally. The Gabor function is adopted the analyzing wavelet. The wavelet analysis shows that the variations of ultrasonic group velocity and attenuation coefficient due to the change of material characterization can be evaluated at each frequency. Furthermore, to assure the enhancement of detectability and new sizing performance, both computer simulated results and experimental measurements using wavelet signal processing are used to demonstrate the effectiveness of the noise suppression of ultrasonic flaw signal obtained from austenitic stainless steel weld including EDM notch

Design, fabrication, commissioning, and testing of a 250 g/s, 2-K helium cold compressor system

International Nuclear Information System (INIS)

V. Ganni; D. M. Arenius; B. S. Bevins; W. C. Chronis; J. D. Creel; J. D. Wilson Jr.

2002-01-01

In June 1999 the Thomas Jefferson National Accelerator Facility (TJNAF) Cryogenic Systems Group had completed the design, fabrication, and commissioning of a cold compressor system capable of pumping 250 g/s of 2-K helium vapor to a pressure above 1 bar. The 2-K cold box consists of five stages of centrifugal variable speed compressors with LN2 cooled drive motors and magnetic bearings, a plate fin heat exchanger, and an LN2 shield system. The new 2-K cold box (referred to as the SCN) was built as a redundant system to an existing four stage cold compressor SCM cold box that was commissioned in May 1994. The SCN has been in continuous service supporting the facility experiments since commissioning. This system has achieved a significant improvement in the total 2-K refrigeration system capacity and stability and has substantially increased the operating envelope both in cold compressor flow and operating pressure range. This paper describes the cold box configuration and the experience s in the design, fabrication, commissioning and performance evaluation. The capacity of the system for various operating pressures (0.040 to 0.025 bar at the load corresponding to a total compressor pressure ratio of 28 to 54) is presented. An effort is made to characterize the components and their operating data over the tested range. This includes the return side pressure drop in the distribution system, the heat exchanger, and the cold compressor characteristics. The system design parameters and their effects on performance are outlined

Automated ultrasonic inspection using PULSDAT

International Nuclear Information System (INIS)

Naybour, P.J.

1992-01-01

PULSDAT (Portable Ultrasonic Data Acquisition Tool) is a system for recording the data from single probe automated ultrasonic inspections. It is one of a range of instruments and software developed by Nuclear Electric to carry out a wide variety of high quality ultrasonic inspections. These vary from simple semi-automated inspections through to multi-probe, highly automated ones. PULSDAT runs under the control of MIPS software, and collects data which is compatible with the GUIDE data display system. PULSDAT is therefore fully compatible with Nuclear Electric's multi-probe inspection systems and utilises all the reliability and quality assurance of the software. It is a rugged, portable system that can be used in areas of difficult access. The paper discusses the benefits of automated inspection and gives an outline of the main features of PULSDAT. Since April 1990 PULSDAT has been used in several applications within Nuclear Electric and this paper presents two examples: the first is a ferritic set-through nozzle and the second is an austenitic fillet weld. (Author)

Cold injuries.

Science.gov (United States)

Kruse, R J

1995-01-01

There are two categories of cold injury. The first is hypothermia, which is a systemic injury to cold, and the second is frostbite, which is a local injury. Throughout history, entire armies, from George Washington to the Germans on the Russian Front in World War II, have fallen prey to prolonged cold exposure. Cold injury is common and can occur in all seasons if ambient temperature is lower than the core body temperature. In the 1985 Boston Marathon, even though it was 76 degrees and sunny, there were 75 runners treated for hypothermia. In general, humans adapt poorly to cold exposure. Children are at particular risk because of their relatively greater surface area/body mass ratio, causing them to cool even more rapidly than adults. Because of this, the human's best defense against cold injury is to limit his/her exposure to cold and to dress appropriately. If cold injury has occurred and is mild, often simple passive rewarming such as dry blankets and a warm room are sufficient treatment.

Astrochemical Properties of Planck Cold Clumps

Energy Technology Data Exchange (ETDEWEB)

Tatematsu, Ken’ichi; Sanhueza, Patricio; Nguyễn Lu’o’ng, Quang; Hirota, Tomoya [National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Liu, Tie; Choi, Minho; Kang, Miju; Kim, Kee-Tae [Korea Astronomy and Space Science Institute, Daedeokdaero 776, Yuseong, Daejeon 305-348 (Korea, Republic of); Ohashi, Satoshi [Department of Astronomy, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Liu, Sheng-Yuan; Hirano, Naomi [Academia Sinica Institute of Astronomy and Astrophysics, 11F of Astronomy-Mathematics Building, AS/NTU. No.1, Section 4, Roosevelt Rd, Taipei 10617, Taiwan (China); Thompson, Mark A. [Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Hatfield, AL10 9AB (United Kingdom); Fuller, Gary [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Wu, Yuefang [Department of Astronomy, Peking University, 100871, Beijing (China); Li, Di [National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012 (China); Francesco, James Di [NRC Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Wang, Ke [European Southern Observatory (Germany); Ristorcelli, Isabelle [IRAP, CNRS (UMR5277), Universite Paul Sabatier, 9 avenue du Colonel Roche, BP 44346, F-31028, Toulouse Cedex 4 (France); Juvela, Mika [Department of physics, University of Helsinki, FI-00014, Helsinki (Finland); Shinnaga, Hiroko, E-mail: k.tatematsu@nao.ac.jp [Department of Physics, Kagoshima University, 1-21-35, Korimoto, Kagoshima, 890-0065 (Japan); Collaboration: JCMT Large Program “SCOPE” collaboration; TRAO Key Science Program “TOP” collaboration; and others

2017-02-01

We observed 13 Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The N{sub 2}H{sup +} distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC{sub 3}N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the N{sub 2}H{sup +} emission. The CCS emission, which is known to be abundant in starless molecular cloud cores, is often very clumpy in the observed targets. We made deep single-pointing observations in DNC, HN{sup 13}C, N{sub 2}D{sup +}, and cyclic-C{sub 3}H{sub 2} toward nine clumps. The detection rate of N{sub 2}D{sup +} is 50%. Furthermore, we observed the NH{sub 3} emission toward 15 Planck cold clumps to estimate the kinetic temperature, and confirmed that most targets are cold (≲20 K). In two of the starless clumps we observed, the CCS emission is distributed as it surrounds the N{sub 2}H{sup +} core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and N{sub 2}D{sup +}. These two clumps are most likely on the verge of star formation. We introduce the chemical evolution factor (CEF) for starless cores to describe the chemical evolutionary stage, and analyze the observed Planck cold clumps.

Development of phased-array ultrasonic testing probe

International Nuclear Information System (INIS)

Kawanami, Seiichi; Kurokawa, Masaaki; Taniguchi, Masaru; Tada, Yoshihisa

2001-01-01

Phased-array ultrasonic testing was developed for nondestructive evaluation of power plants. Phased-array UT scans and focuses an ultrasonic beam to inspect areas difficult to inspect by conventional UT. We developed a highly sensitive piezoelectric composite, and designed optimized phased-array UT probes. We are applying our phased-array UT to different areas of power plants. (author)

Automated ultrasonic testing--capabilities, limitations and methods

International Nuclear Information System (INIS)

Beller, L.S.; Mikesell, C.R.

1977-01-01

The requirements for precision and reproducibility of ultrasonic testing during inservice inspection of nuclear reactors are both quantitatively and qualitatively more severe than most current practice in the field can provide. An automated ultrasonic testing (AUT) system, which provides a significant advancement in field examination capabilities, is described. Properties of the system, its application, and typical results are discussed

Gas ultrasonic flow rate measurement through genetic-ant colony optimization based on the ultrasonic pulse received signal model

Science.gov (United States)

Hou, Huirang; Zheng, Dandan; Nie, Laixiao

2015-04-01

For gas ultrasonic flowmeters, the signals received by ultrasonic sensors are susceptible to noise interference. If signals are mingled with noise, a large error in flow measurement can be caused by triggering mistakenly using the traditional double-threshold method. To solve this problem, genetic-ant colony optimization (GACO) based on the ultrasonic pulse received signal model is proposed. Furthermore, in consideration of the real-time performance of the flow measurement system, the improvement of processing only the first three cycles of the received signals rather than the whole signal is proposed. Simulation results show that the GACO algorithm has the best estimation accuracy and ant-noise ability compared with the genetic algorithm, ant colony optimization, double-threshold and enveloped zero-crossing. Local convergence doesn’t appear with the GACO algorithm until -10 dB. For the GACO algorithm, the converging accuracy and converging speed and the amount of computation are further improved when using the first three cycles (called GACO-3cycles). Experimental results involving actual received signals show that the accuracy of single-gas ultrasonic flow rate measurement can reach 0.5% with GACO-3 cycles, which is better than with the double-threshold method.

Actively adjustable step-type ultrasonic horns in longitudinal vibration

Science.gov (United States)

Lin, Shuyu; Guo, Hao; Xu, Jie

2018-04-01

Actively adjustable longitudinal step-type ultrasonic horns are proposed and studied. The horn is composed of a traditional ultrasonic horn and piezoelectric material. In practical applications, this kind of step-type ultrasonic horn is mechanically excited by an ultrasonic transducer and the piezoelectric material is connected to an adjustable electric impedance. In this research, the effects of the electric impedance and of the location of the piezoelectric material on the performance of the horn are studied. It is shown that when the electric resistance is increased, the resonance frequency of the horn is increased; the displacement magnification is increased when the piezoelectric material is located in the large end and decreased when the piezoelectric material is located in the small end of the horn. The displacement magnification for the piezoelectric material in the large end is larger than that for the piezoelectric material in the small end of the horn. Some step-type ultrasonic horns are designed and manufactured; the resonance frequency and the displacement magnification are measured by means of POLYTEC Laser Scanning vibrometer. It is shown that the theoretical resonance frequency and the displacement magnification are in good agreement with the measured results. It is concluded that by means of the insertion of the piezoelectric material in the longitudinal horn, the horn performance can be adjusted by changing the electric impedance and the location of the piezoelectric material in the horn. It is expected that this kind of adjustable ultrasonic horns can be used in traditional and potential ultrasonic technologies where the vibrational performance adjustment is needed.

Mid-IR laser ultrasonic testing for fiber reinforced plastics

Science.gov (United States)

Kusano, Masahiro; Hatano, Hideki; Oguchi, Kanae; Yamawaki, Hisashi; Watanabe, Makoto; Enoki, Manabu

2018-04-01

Ultrasonic testing is the most common method to detect defects in materials and evaluate their sizes and locations. Since piezo-electric transducers are manually handled from point to point, it takes more costs for huge products such as airplanes. Laser ultrasonic testing (LUT) is a breakthrough technique. A pulsed laser generates ultrasonic waves on a material surface due to thermoelastic effect or ablation. The ultrasonic waves can be detected by another laser with an interferometer. Thus, LUT can realize instantaneous inspection without contacting a sample. A pulse laser with around 3.2 μm wavelength (in the mid-IR range) is more suitable to generate ultrasonic waves for fiber reinforced plastics (FRPs) because the light is well absorbed by the polymeric matrix. On the other hand, such a laser is not available in the market. In order to emit the mid-IR laser pulse, we came up with the application of an optical parametric oscillator and developed an efficient wavelength conversion device by pumping a compact Nd:YAG solid-state laser. Our mid-IR LUT system is most suitable for inspection of FRPs. The signal-to-noise ratio of ultrasonic waves generated by the mid-IR laser is higher than that by the Nd:YAG laser. The purpose of the present study is to evaluate the performance of the mid-IR LUT system in reflection mode. We investigated the effects of the material properties and the laser properties on the generated ultrasonic waves. In addition, C-scan images by the system were also presented.

Method of case hardening depth testing by using multifunctional ultrasonic testing instrument

International Nuclear Information System (INIS)

Salchak, Y A; Sednev, D A; Ardashkin, I B; Kroening, M

2015-01-01

The paper describes usability of ultrasonic case hardening depth control applying standard instrument of ultrasonic inspections. The ultrasonic method of measuring the depth of the hardened layer is proposed. Experimental series within the specified and multifunctional ultrasonic equipment are performed. The obtained results are compared with the results of a referent method of analysis. (paper)

Proceedings of the specialists' meeting on reliability of the ultrasonic inspection of austenitic materials

Energy Technology Data Exchange (ETDEWEB)

NONE

1980-07-01

The contributions of this meeting addressed several topics: the fundamentals of ultrasonic examination of austenitic materials (effect of anisotropy on propagation, improvement of ultrasonic testing to thick bimetallic welds, aspects of the ultrasonic testing of austenitic steel structures, utilization of a Fisher linear discriminant function in intergranular stress corrosion cracking or IGSCC detection, case of coarse grain austenitic welds, efforts of the Argonne National Laboratory), instruments and methods (longitudinal wave ultrasonic inspection, Grass echo suppression technique during the ultrasonic inspection of fuel cladding tubes, inspections of fillet and butt welds, improvement by signal averaging techniques, multiple bearing angle crack detector for cladded pipes examinations, flow-to-grain echo enhancement by split-spectrum processing, ultrasonic imaging techniques, ultrasonic inspection of pipe weldments for IGSCC), industrial practice (ultrasonic testing techniques for fabrication and in-service inspection, experiences in ultrasonic examination of austenitic steel components, experience and practice on nuclear piping in Spain, detection of underclad defects, sizing of cracks perpendicular to stainless overlay), and reliability (survey of ultrasonic testing in austenitic weld material, examination of electron beam welds, factors affecting the reliability of ultrasonic examination, detectability of IGSCC, ultrasonic inspection reliability for primary piping systems)

Proceedings of the specialists' meeting on reliability of the ultrasonic inspection of austenitic materials

International Nuclear Information System (INIS)

1980-01-01

The contributions of this meeting addressed several topics: the fundamentals of ultrasonic examination of austenitic materials (effect of anisotropy on propagation, improvement of ultrasonic testing to thick bimetallic welds, aspects of the ultrasonic testing of austenitic steel structures, utilization of a Fisher linear discriminant function in intergranular stress corrosion cracking or IGSCC detection, case of coarse grain austenitic welds, efforts of the Argonne National Laboratory), instruments and methods (longitudinal wave ultrasonic inspection, Grass echo suppression technique during the ultrasonic inspection of fuel cladding tubes, inspections of fillet and butt welds, improvement by signal averaging techniques, multiple bearing angle crack detector for cladded pipes examinations, flow-to-grain echo enhancement by split-spectrum processing, ultrasonic imaging techniques, ultrasonic inspection of pipe weldments for IGSCC), industrial practice (ultrasonic testing techniques for fabrication and in-service inspection, experiences in ultrasonic examination of austenitic steel components, experience and practice on nuclear piping in Spain, detection of underclad defects, sizing of cracks perpendicular to stainless overlay), and reliability (survey of ultrasonic testing in austenitic weld material, examination of electron beam welds, factors affecting the reliability of ultrasonic examination, detectability of IGSCC, ultrasonic inspection reliability for primary piping systems)

Combination of Ultrasonic Vibration and Cryogenic Cooling for Cutting Performance Improvement of Inconel 718 Turning

Science.gov (United States)

Lin, S. Y.; Chung, C. T.; Cheng, Y. Y.

2011-01-01

The main objective of this study is to develop a thermo-elastic-plastic coupling model, based on a combination skill of ultrasonically assisted cutting and cryogenic cooling, under large deformation for Inconel 718 alloy machining process. The improvement extent on cutting performance and tool life promotion may be examined from this investigation. The critical value of the strain energy density of the workpiece will be utilized as the chip separation and the discontinuous chip segmentation criteria. The forced convection cooling and a hydrodynamic lubrication model will be considered and formulated in the model. Finite element method will be applied to create a complete numerical solution for this ultrasonic vibration cutting model. During the analysis, the cutting tool is incrementally advanced forward with superimposed ultrasonic vibration in a back and forth step-by-step manner, from an incipient stage of tool-workpiece engagement to a steady state of chip formation, a whole simulation of orthogonal cutting process under plane strain deformation is thus undertaken. High shear strength induces a fluctuation phenomenon of shear angle, high shear strain rate, variation of chip types and chip morphology, tool-chip contact length variation, the temperature distributions within the workpiece, chip and tool, periodic fluctuation in cutting forces can be determined from the developed model. A complete comparison of machining characteristics between some different combinations of ultrasonically assisted cutting and cryogenic cooling with conventional cutting operation can be acquired. Finally, the high-speed turning experiment for Inconel 718 alloy will be taken in the laboratory to validate the accuracy of the model, and the progressive flank wear, crater wear, notching and chipping of the tool edge can also be measured in the experiments.

Theoretical and experimental investigations on the cooling capacity distributions at the stages in the thermally-coupled two-stage Stirling-type pulse tube cryocooler without external precooling

Science.gov (United States)

Tan, Jun; Dang, Haizheng

2017-03-01

The two-stage Stirling-type pulse tube cryocooler (SPTC) has advantages in simultaneously providing the cooling powers at two different temperatures, and the capacity in distributing these cooling capacities between the stages is significant to its practical applications. In this paper, a theoretical model of the thermally-coupled two-stage SPTC without external precooling is established based on the electric circuit analogy with considering real gas effects, and the simulations of both the cooling performances and PV power distribution between stages are conducted. The results indicate that the PV power is inversely proportional to the acoustic impedance of each stage, and the cooling capacity distribution is determined by the cold finger cooling efficiency and the PV power into each stage together. The design methods of the cold fingers to achieve both the desired PV power and the cooling capacity distribution between the stages are summarized. The two-stage SPTC is developed and tested based on the above theoretical investigations, and the experimental results show that it can simultaneously achieve 0.69 W at 30 K and 3.1 W at 85 K with an electric input power of 330 W and a reject temperature of 300 K. The consistency between the simulated and the experimental results is observed and the theoretical investigations are experimentally verified.

Detection of Fatigue Damage by Using Frequency Attenuation of a Laser Ultrasonic Longitudinal Wave

International Nuclear Information System (INIS)

Park, Seung-Kyu; Baik, Sung-Hoon; Jung, Hyun-Kyu; Joo, Young-Sang; Cha, Hyung-Ki; Kang, Young-June

2006-01-01

The measurement of fatigue damage in nuclear power plant components is very important to prevent a catastrophic accident and the subsequent severe losses. Specifically, it is preferred to detect at an early stage of the fatigue damage. If the fatigue damage that is in danger of growing into a fracture is accurately detected, an appropriate treatment could be carried out to improve the condition. Although most engineers and designers take precautions against fatigue, some breakdowns of nuclear power plant components still occur due to fatigue damage. It is considered that ultrasound testing technique is the most promising method to detect the fatigue damage in many nondestructive testing methods. Ultrasound testing method has a variety of elastic waves, such as a longitudinal wave, a shear wave, a surface wave and a lamb wave. Also we can use various analysis methods, such as a velocity variation and a signal attenuation. Laser ultrasonic testing has attracted attention as a non-contact testing technique. This system consists of a pulse laser to remotely generate ultrasound and a laser interferometer to remotely measure the surface displacement due to the generated ultrasound. This noncontact testing technique has the following advantages over the conventional piezoelectric transducers. Firstly, the inspection system can be remotely operated for a structure in hostile environments, such as in high radioactivity, high temperatures and narrow spaces. Secondly, we can obtain lots of information from the received ultrasonic waveforms because the laser ultrasonic technique does not require fluid couplant which disturbs the ultrasonic waveforms. Thirdly, laser ultrasound has a wideband spectrum and a high spatial resolution. Therefore, the laser ultrasound provides more accurate information for a testing material and has potential for the detection of fatigue damage in various metals composing a nuclear power plant

Ultrasonic testing using time of flight diffraction technique (TOFD)

International Nuclear Information System (INIS)

Khurram Shahzad; Ahmad Mirza Safeer Ahmad; Muhammad Asif Khan

2009-04-01

This paper describes the ultrasonic testing using Time Flight Diffraction (TOFD) Technique for welded samples having different types and sizes of defects. TOFD is a computerized ultrasonic system, able to scan, store and evaluate indications in terms of location, through thickness and length in a more easy and convenient. Time of Flight Diffraction Technique (TOFD) is more fast and easy technique for ultrasonic testing as we can examine a weld i a single scan along the length of the weld with two probes known as D-scan. It shows the image of the complete weld with the defect information. The examinations were performed on carbon steel samples used for ultrasonic testing using 70 degree probes. The images for different type of defects were obtained. (author)

Ultrasonic-resonator-combined apparatus for purifying nuclear aerosol particles

Energy Technology Data Exchange (ETDEWEB)

Hou, Suxia; Zhang, Quanhu; Li, Sufen; Chen, Chen; Su, Xianghua [Xi' an Hi-Tech Institute, Xi' an (China)

2017-12-15

The radiation hazards of radionuclides in the air arising from the storage room of nuclear devices to the operators cannot be ignored. A new ultrasonic-resonator-combined method for purifying nuclear aerosol particles is introduced. To remove particles with diameters smaller than 0.3 μm, an ultrasonic chamber is induced to agglomerate these submicron particles. An apparatus which is used to purify the nuclear aerosol particles is described in the article. The apparatus consists of four main parts: two filtering systems, an ultrasonic chamber and a high-pressure electrostatic precipitator system. Finally, experimental results demonstrated the effectiveness of the implementation of the ultrasonic resonators. The feasibility of the method is proven by its application to the data analysis of the experiments.

Ultrasonic Generation and Optimization for EMAT

International Nuclear Information System (INIS)

Jian, X.; Dixon, Steve; Edwards, Rachel S.

2005-01-01

A model for transient ultrasonic wave generation by EMATs in non-magnetic metals is presented. It combines analytical solutions currently available and FEM to calculate ultrasonic bulk and Rayleigh waves generated by the EMAT. Analytical solutions are used as they can be calculated quickly on a standard mathematical computer package. Calculations agree well with the experimental measurement. The model can be used to optimize EMAT design, and has explained some of the results from our previous published measurements

Longitudinal ultrasonic waves dispersion in bars

International Nuclear Information System (INIS)

Suarez Antola, R.

2001-01-01

The exhibition intends to review some aspects of the propagation of the longitudinal ultrasonic pulses shortly in bars of traverse section uniform.Aspects they are part of the denominated geometric dispersion of the pulses.This phenomenon It can present like an additional complication in the ultrasonic essay of low frequency of thin pieces in structures and machines but takes place former ex professed in some applications of the wave guides been accustomed to in the prosecution of signs

Ultrasonic hot powder compaction of Ti-6Al-4V.

Science.gov (United States)

Abedini, Rezvan; Abdullah, Amir; Alizadeh, Yunes

2017-07-01

Power ultrasonic has been recently employed in a wide variety of manufacturing processes among which ultrasonic assisted powder compaction is a promising powder materials processing technique with significant industrial applications. The products manufactured by the powder metallurgy commonly consist of residual porosities, material impurities, structural non-homogeneities and residual stress. In this paper, it is aimed to apply power ultrasonic to the hot consolidation process of Ti-6Al-4V titanium alloy powder in order to improve mechanical properties. To do this, the effects of ultrasonic power and process temperature and pressure were considered and then deeply studied through a series of experiments. It was shown that the addition of ultrasonic vibration leads to a significant improvement in the consolidation performance and the mechanical strength of the fabricated specimens. Copyright © 2017 Elsevier B.V. All rights reserved.

A Miniature Probe for Ultrasonic Penetration of a Single Cell

Directory of Open Access Journals (Sweden)

Mingfei Xiao

2009-05-01

Full Text Available Although ultrasound cavitation must be avoided for safe diagnostic applications, the ability of ultrasound to disrupt cell membranes has taken on increasing significance as a method to facilitate drug and gene delivery. A new ultrasonic resonance driving method is introduced to penetrate rigid wall plant cells or oocytes with springy cell membranes. When a reasonable design is created, ultrasound can gather energy and increase the amplitude factor. Ultrasonic penetration enables exogenous materials to enter cells without damaging them by utilizing instant acceleration. This paper seeks to develop a miniature ultrasonic probe experiment system for cell penetration. A miniature ultrasonic probe is designed and optimized using the Precise Four Terminal Network Method and Finite Element Method (FEM and an ultrasonic generator to drive the probe is designed. The system was able to successfully puncture a single fish cell.

A study on the development of a real-time intelligent system for ultrasonic flaw classification

International Nuclear Information System (INIS)

Song, Sung Jin; Kim, Hak Joon; Lee, Hyun; Lee, Seung Seok

1998-01-01

In spite of significant progress in research on ultrasonic pattern recognition it is not widely used in many practical field inspection in weldments. For the convenience of field application of this methodology, following four key issues have to be suitably addressed; 1) a software where the ultrasonic pattern recognition algorithm is efficiently implemented, 2) a real-time ultrasonic testing system which can capture the digitized ultrasonic flaw signal so the pattern recognition software can be applied in a real-time fashion, 3) database of ultrasonic flaw signals in weldments, which is served as a foundation of the ultrasonic pattern recognition algorithm, and finally, 4) ultrasonic features which should be invariant to operational variables of the ultrasonic test system. Presented here is the recent progress in the development of a real-time ultrasonic flaw classification by the novel combination of followings; an intelligent software for ultrasonic flaw classification in weldments, a computer-base real-time ultrasonic nondestructive evaluation system, database of ultrasonic flaw signals, and invariant ultrasonic features called 'normalized features.'

Research of the ultrasonic testing parts reconditioned by welding

Directory of Open Access Journals (Sweden)

C. Petriceanu

2016-07-01

Full Text Available The paper presents the results obtained following the nondestructive ultrasonic testing of crankpin shaft of a crankshaft that were reconditioned by welding. After the ultrasonic testing, the reconditioned samples were cut and subjected to visual testing and microstructure examination. When the results obtained following the nondestructive tests were analyzed, it was observed that the ultrasonic nondestructive testing method is an efficient way to determine the conformity of the areas that were reconditioned by welding.

Ultrasonic-assisted manufacturing processes: Variational model and numerical simulations

KAUST Repository

Siddiq, Amir; El Sayed, Tamer

2012-01-01

We present a computational study of ultrasonic assisted manufacturing processes including sheet metal forming, upsetting, and wire drawing. A fully variational porous plasticity model is modified to include ultrasonic softening effects

A capacitive ultrasonic transducer based on parametric resonance

Science.gov (United States)

Surappa, Sushruta; Satir, Sarp; Levent Degertekin, F.

2017-07-01

A capacitive ultrasonic transducer based on a parametric resonator structure is described and experimentally demonstrated. The transducer structure, which we call capacitive parametric ultrasonic transducer (CPUT), uses a parallel plate capacitor with a movable membrane as part of a degenerate parametric series RLC resonator circuit with a resonance frequency of fo. When the capacitor plate is driven with an incident harmonic ultrasonic wave at the pump frequency of 2fo with sufficient amplitude, the RLC circuit becomes unstable and ultrasonic energy can be efficiently converted to an electrical signal at fo frequency in the RLC circuit. An important characteristic of the CPUT is that unlike other electrostatic transducers, it does not require DC bias or permanent charging to be used as a receiver. We describe the operation of the CPUT using an analytical model and numerical simulations, which shows drive amplitude dependent operation regimes including parametric resonance when a certain threshold is exceeded. We verify these predictions by experiments with a micromachined membrane based capacitor structure in immersion where ultrasonic waves incident at 4.28 MHz parametrically drive a signal with significant amplitude in the 2.14 MHz RLC circuit. With its unique features, the CPUT can be particularly advantageous for applications such as wireless power transfer for biomedical implants and acoustic sensing.

Ultrasonic imaging of material flaws exploiting multipath information

Science.gov (United States)

Shen, Xizhong; Zhang, Yimin D.; Demirli, Ramazan; Amin, Moeness G.

2011-05-01

In this paper, we consider ultrasonic imaging for the visualization of flaws in a material. Ultrasonic imaging is a powerful nondestructive testing (NDT) tool which assesses material conditions via the detection, localization, and classification of flaws inside a structure. Multipath exploitations provide extended virtual array apertures and, in turn, enhance imaging capability beyond the limitation of traditional multisensor approaches. We utilize reflections of ultrasonic signals which occur when encountering different media and interior discontinuities. The waveforms observed at the physical as well as virtual sensors yield additional measurements corresponding to different aspect angles. Exploitation of multipath information addresses unique issues observed in ultrasonic imaging. (1) Utilization of physical and virtual sensors significantly extends the array aperture for image enhancement. (2) Multipath signals extend the angle of view of the narrow beamwidth of the ultrasound transducers, allowing improved visibility and array design flexibility. (3) Ultrasonic signals experience difficulty in penetrating a flaw, thus the aspect angle of the observation is limited unless access to other sides is available. The significant extension of the aperture makes it possible to yield flaw observation from multiple aspect angles. We show that data fusion of physical and virtual sensor data significantly improves the detection and localization performance. The effectiveness of the proposed multipath exploitation approach is demonstrated through experimental studies.

Analysis of ultrasonic techniques for the characterization of microfiltration polymeric membranes

International Nuclear Information System (INIS)

Lucas, Carla S.; Baroni, Douglas B.; Costa, Antonio M.L.M.; Bittencourt, Marcelo S.Q.

2009-01-01

The use of polymeric membranes is extremely important in several industries such as nuclear, biotechnology, chemical and pharmaceutical. In the nuclear area, for instance, systems based on membrane separation technologies are currently being used in the treatment of radioactive liquid effluent, and new technologies using membranes are being developed at a great rate. The knowledge of the physical characteristics of these membranes, such as, pore size and the pore size distribution, is very important to the membranes separation processes. Only after these characteristics are known is it possible to determine the type and to choose a particular membrane for a specific application. In this work, two ultrasonic non destructive techniques were used to determine the porosity of membranes: pulse echo and transmission. A 25 MHz immersion transducer was used. Ultrasonic signals were acquired, for both techniques, after the ultrasonic waves passed through a microfiltration polymeric membrane of pore size of 0.45 μm and thickness of 180 μm. After the emitted ultrasonic signal crossed the membrane, the received signal brought several information on the influence of the membrane porosity in the standard signal of the ultrasonic wave. The ultrasonic signals were acquired in the time domain and changed to the frequency domain by application of the Fourier Fast Transform (FFT), thus generating the material frequency spectrum. For the pulse echo technique, the ultrasonic spectrum frequency changed after the ultrasonic wave crossed the membrane. With the transmission technique there was only a displacement of the ultrasonic signal at the time domain. (author)

Nondestructive evaluation of a cermet coating using ultrasonic and eddy current techniques

International Nuclear Information System (INIS)

Roge, B.; Fahr, A.; Giguere, J.S.R.; McRae, K.I.

2002-01-01

This paper describes a series of experiments conducted to characterize cermet coatings using conventional ultrasonic and eddy current techniques as well as an ultrasonic leaky surface wave method. The results demonstrate the ability of these techniques to detect the presence of artificial defects on the surface or beneath the surface of the coating. In addition, ultrasonic tests in particular ultrasonic leaky surface waves demonstrate the ability to detect the presence of manufacturing flaws. Ultrasonic time-of-flight and eddy current quadrature measurements also show sensitivity to variations in coating thickness

Reproducibility of the results in ultrasonic testing

International Nuclear Information System (INIS)

Chalaye, M.; Launay, J.P.; Thomas, A.

1980-12-01

This memorandum reports on the conclusions of the tests carried out in order to evaluate the reproducibility of ultrasonic tests made on welded joints. FRAMATOME have started a study to assess the dispersion of results afforded by the test line and to characterize its behaviour. The tests covered sensors and ultrasonic generators said to be identical to each other (same commercial batch) [fr

Artificial intelligence and ultrasonic tests in detection of defects

International Nuclear Information System (INIS)

Barrera Cardiel, G.; Fabian Alvarez, M. a.; Velez Martinez, M.; Villasenor, L.

2001-01-01

One of the most serious problems in the quality control of welded unions is the location, identification and classification of defects. As a solution to this problem, a technique for classification, applicable to welded unions done by electric arc welding as well as by friction, is proposed; it is based on ultrasonic signals. The neuronal networks proposed are Kohonen and Multilayer Percept ron, all in a virtual instrument environment. Currently the techniques most used in this field are: radiological analysis (X-rays) and ultrasonic analysis (ultrasonic waves). The X-ray technique in addition to being dangerous requires highly specialized personnel and equipment, therefore its use is restricted. The ultrasonic technique, in spite of being one of the most used for detection of discontinuities, requires personnel with wide experience in the interpretation of ultrasonic signals, this is a time-consuming process which necessarily increases its operation cost. The classification techniques that we propose turn out to be safe, reliable, inexpensive and easy to implement for the solution of this important problem. (Author) 8 refs

Inspection of austenitic welds with ultrasonic phased array technology

Energy Technology Data Exchange (ETDEWEB)

Garcia, A.; Fernandez, F. [Tecnatom (Spain); Dutruc, R.; Ferriere, R. [Metalscan (France)

2011-07-01

This series of slides presents the use of ultrasonic phased array technology in the inspection of austenitic welds. The inspection from outside surface (the inspection is performed in contact using wedges to couple the probe to the outer surface of the component) shows that longitudinal wave is the most adequate for perpendicular scans and transversal ultrasonic wave is the most adequate for parallel scans. Detection and length sizing are performed optimally in perpendicular scans. The inspection from inside surface shows: -) Good results in the detection of defects (Sizing has met the requirements imposed by the Authority of the Russian Federation); -) The new design of the mechanical equipment and of the numerous ultrasonic beams refracted by the array probes has increased the volume inspected. The design of the mechanical equipment has also allowed new areas to be inspected (example a piping weld that was not accessible from the outer surface; -) The ultrasonic procedure and Inspection System developed have been validated by the Authority of the Russian Federation. Phase array technique supplies solutions to solve accessibility concerns and improve the ultrasonic inspections of nuclear components

Ultrasonic testing X gammagraphy

International Nuclear Information System (INIS)

Mello Campos, A.M. de

1989-01-01

The experience of 10 years for substituting gammagraphy tests by ultrasonic tests is related. A comparative evaluation of data obtained from both techniques applied to welded butt joints is presented. (author)

Ultrasonic partial discharge monitoring method on instrument transformers

Directory of Open Access Journals (Sweden)

Kartalović Nenad

2012-01-01

Full Text Available Sonic and ultrasonic partial discharge monitoring have been applied since the early days of these phenomena monitoring. Modern measurement and partial discharge acoustic (ultrasonic and sonic monitoring method has been rapidly evolving as a result of new electronic component design, information technology and updated software solutions as well as the development of knowledge in the partial discharge diagnosis. Electrical discharges in the insulation system generate voltage-current pulses in the network and ultrasonic waves that propagate through the insulation system and structure. Amplitude-phase-frequency analysis of these signals reveals information about the intensity, type and location of partial discharges. The paper discusses the possibility of ultrasonic method selectivity improvement and the increase of diagnosis reliability in the field. Measurements were performed in the laboratory and in the field while a number of transformers were analysed for dissolved gases in the oil. A comparative review of methods for the partial discharge detection is also presented in this paper.

Ultrasonic texture characterization of aluminum, zirconium and titanium alloys

International Nuclear Information System (INIS)

Anderson, A.J.

1997-01-01

This work attempts to show the feasibility of nondestructive characterization of non-ferrous alloys. Aluminum alloys have a small single crystal anisotropy which requires very precise ultrasonic velocity measurements for derivation of orientation distribution coefficients (ODCs); the precision in the ultrasonic velocity measurement required for aluminum alloys is much greater than is necessary for iron alloys or other alloys with a large single crystal anisotropy. To provide greater precision, some signal processing corrections need to be applied to account for the inherent, half-bandwidth offset in triggered pulses when using a zero-crossing technique for determining ultrasonic velocity. In addition, alloys with small single crystal anisotropy show a larger dependence on the single crystal elastic constants (SCECs) when predicting ODCs which require absolute velocity measurements. Attempts were made to independently determine these elastics constants in an effort to improve correlation between ultrasonically derived ODCs and diffraction derived ODCs. The greater precision required to accurately derive ODCs in aluminum alloys using ultrasonic nondestructive techniques is easily attainable. Ultrasonically derived ODCs show good correlation with derivations made by Bragg diffraction techniques, both neutron and X-ray. The best correlation was shown when relative velocity measurements could be used in the derivations of the ODCs. Calculation of ODCs in materials with hexagonal crystallites can also be done. Because of the crystallite symmetries, more information can be extracted using ultrasonic techniques, but at a cost of requiring more physical measurements. Some industries which use materials with hexagonal crystallites, e.g. zirconium alloys and titanium, have traditionally used texture parameters which provide some specialized measure of the texture. These texture parameters, called Kearns factors, can be directly related to ODCs

Fabrication Improvement of Cold Forging Hexagonal Nuts by Computational Analysis and Experiment Verification

Directory of Open Access Journals (Sweden)

Shao-Yi Hsia

2015-01-01

Full Text Available Cold forging has played a critical role in fasteners and has been applied to the automobile industry, construction industry, aerospace industry, and living products so that cold forging presents the opportunities for manufacturing more products. By using computer simulation, this study attempts to analyze the process of creating machine parts, such as hexagonal nuts. The DEFORM-3D forming software is applied to analyze the process at various stages in the computer simulation, and the compression test is also used for the flow stress equation in order to compare the differences between the experimental results and the equation that is built into the computer simulation software. At the same time, the metallography and hardness of experiments are utilized to understand the cold forging characteristics of hexagonal nuts. The research results would benefit machinery businesses to realize the forging load and forming conditions at various stages before the fastener formation. In addition to planning proper die design and production, the quality of the produced hexagonal nuts would be more stable to promote industrial competitiveness.

A comparison of Frost expression among species and life stages of Drosophila.

Science.gov (United States)

Bing, X; Zhang, J; Sinclair, Brent J

2012-02-01

Frost (Fst) is a gene associated with cold exposure in Drosophila melanogaster. We used real-time PCR to assess whether cold exposure induces expression of Fst in 10 different life stages of D. melanogaster, and adults of seven other Drosophila species. We exposed groups of individuals to 0 °C (2 h), followed by 1 h recovery (22 °C). Frost was significantly upregulated in response to cold in eggs, third instar larvae, and 2- and 5-day-old male and female adults in D. melanogaster. Life stages in which cold did not upregulate Fst had high constitutive expression. Frost is located on the opposite strand of an intron of Diuretic hormone (DH), but cold exposure did not upregulate DH. Frost orthologues were identified in six other species within the Melanogaster group (Drosophila sechellia, Drosophila simulans, Drosophila yakuba, Drosophila erecta, Drosophila ananassae and Drosophila mauritiana). Frost orthologues were upregulated in response to cold exposure in both sexes in adults of all of these species. The predicted structure of a putative Frost consensus protein shows highly conserved tandem repeats of motifs involved in cell signalling (PEST and TRAF2), suggesting that Fst might encode an adaptor protein involved in acute stress or apoptosis signalling in vivo. © 2011 The Authors. Insect Molecular Biology © 2011 The Royal Entomological Society.

Quadrature demodulation based circuit implementation of pulse stream for ultrasonic signal FRI sparse sampling

International Nuclear Information System (INIS)

Shoupeng, Song; Zhou, Jiang

2017-01-01

Converting ultrasonic signal to ultrasonic pulse stream is the key step of finite rate of innovation (FRI) sparse sampling. At present, ultrasonic pulse-stream-forming techniques are mainly based on digital algorithms. No hardware circuit that can achieve it has been reported. This paper proposes a new quadrature demodulation (QD) based circuit implementation method for forming an ultrasonic pulse stream. Elaborating on FRI sparse sampling theory, the process of ultrasonic signal is explained, followed by a discussion and analysis of ultrasonic pulse-stream-forming methods. In contrast to ultrasonic signal envelope extracting techniques, a quadrature demodulation method (QDM) is proposed. Simulation experiments were performed to determine its performance at various signal-to-noise ratios (SNRs). The circuit was then designed, with mixing module, oscillator, low pass filter (LPF), and root of square sum module. Finally, application experiments were carried out on pipeline sample ultrasonic flaw testing. The experimental results indicate that the QDM can accurately convert ultrasonic signal to ultrasonic pulse stream, and reverse the original signal information, such as pulse width, amplitude, and time of arrival. This technique lays the foundation for ultrasonic signal FRI sparse sampling directly with hardware circuitry. (paper)

Using piezoelectric sensors for ultrasonic pulse velocity measurements in concrete

International Nuclear Information System (INIS)

Kee, Seong-Hoon; Zhu, Jinying

2013-01-01

The ultrasonic pulse velocity (UPV) test has been a widely used non-destructive testing method for concrete structures. However, the conventional UPV test has limitations in consistency of results and applicability in hard-to-access regions of structures. The authors explore the feasibility of embedded piezoelectric (PZT) sensors for ultrasonic measurements in concrete structures. Two PZT sensors were embedded in a reinforced concrete specimen. One sensor worked as an actuator driven by an ultrasonic pulse-receiver, and another sensor worked as a receiver. A series of ultrasonic tests were conducted to investigate the performance of the embedded sensors in crack-free concrete and concrete specimens having a surface-breaking crack under various external loadings. Signals measured by the embedded sensors show a broad bandwidth with a centre frequency around 80 kHz, and very good coherence in the frequency range from 30 to 180 kHz. Furthermore, experimental variability in ultrasonic pulse velocity and attenuation is substantially reduced compared to previously reported values from conventional UPV equipment. Findings from this study demonstrate that the embedded sensors have great potential as a low-cost solution for ultrasonic transducers for health monitoring of concrete in structures. (paper)

Fundamentals and Applications of Ultrasonic Waves

CERN Document Server

Cheeke, J David N

2012-01-01

Designed specifically for newcomers to the field, this fully updated second edition begins with fundamentals and quickly advances beyond general wave concepts into an in-depth treatment of ultrasonic waves in isotropic media. Focusing on the physics of acoustic waves, their propagation, technology, and applications, this accessible overview of ultrasonics includes accounts of viscoelasticity and multiple scattering. It examines new technologies, including atomic force acoustic microscopy, lasers, micro-acoustics, and nanotechnology. In addition, it highlights both direct and indirect applicati

The ultrasonic shop map and its use in preservice inspection

International Nuclear Information System (INIS)

Caplan, J.S.

1975-01-01

Prior to the introduction of Section X1 of the ASME Code on Inservice Inspection, a plan was introduced by Westinghouse to perform ultrasonic examinations of areas of high stress and high fluence of reactor pressure vessels in the manufacturer's shop and subsequent to the shop hydrostatic test. The tests provided a shop reference map of ultrasonic responses to use in subsequent preservice and inservice inspections, and attempted to locate any ultrasonic reflections beyond the acceptance standards of ASME Section III and, later, of Section X1. The history of the program is reviewed. Thirty-six vessels were examined during 1970 to 1973. As a result of indications discovered during ultrasonic examination repairs were carried out on five of these. Details are given of inspections and repairs. A summary is also given of the indications detected and of the correlations between the ultrasonic evaluation and actual flow characteristics. (U.K.)

An intelligent software approach to ultrasonic flaw classification in weldments

International Nuclear Information System (INIS)

Song, Sung Jin; Kim, Hak Joon; Lee, Hyun

1997-01-01

Ultrasonic pattern recognition is the most effective approach to the problem of discriminating types of flaws in weldments based on ultrasonic flaw signals. In spite of significant progress on this methodology, it has not been widely used in practical ultrasonic inspection of weldments in industry. Hence, for the convenient application of this approach in many practical situations, we develop an intelligent ultrasonic signature classification software which can discriminate types of flaws in weldments using various tools in artificial intelligence such as neural networks. This software shows excellent performances in an experimental problem where flaws in weldments are classified into two categories of cracks and non-cracks.

Ultrasonic testing device having an adjustable water column

Science.gov (United States)

Roach, Dennis P.; Neidigk, Stephen O.; Rackow, Kirk A.; Duvall, Randy L.

2015-09-01

An ultrasonic testing device having a variable fluid column height is disclosed. An operator is able to adjust the fluid column height in real time during an inspection to to produce optimum ultrasonic focus and separate extraneous, unwanted UT signals from those stemming from the area of interest.

Cold deformation of ADI castings: Martensitic transformation

International Nuclear Information System (INIS)

Navea, Lilian R; Mannheim, Rodolfo M; Garin, Jorge L

2004-01-01

Research and applications in austempered ductile iron (ADI castings) have recently undergone noticeable progress in the industrialized world, becoming a highly competitive engineering material. The notable properties of these castings derive from their austenitic matrix stabilized by carbon, a thermally stable austenite during the austenizing process but possibly turning into martensite when undergoing plastic deformation. This work aims to study the changing structure of an ADI casting caused by one directional cold lamination. The samples that were studied were obtained from two nodular castings, one without alloying and the other alloyed with Cu, Ni and Mo. The samples were austenized in the first stage of the austempering process at 910 o C for 80 min. Then in the second stage the unalloyed samples were austempered at 410 o C for 10 min and the alloyed samples for 120 min. After the thermal treatment, the test pieces were deformed 0% to 25% by cold lamination. The quantification of the phases was performed using x-ray diffraction and the metallographic study using optic and Scanning Electronic Microscopy. The results show that the martensitic phase obtained by deformation is a very fine structure that evolves into a thicker one when the deformation of the samples increases (CW)

Ultrasonic/Sonic Rotary-Hammer Drills

Science.gov (United States)

Badescu, Mircea; Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Kassab, Steve

2010-01-01

Ultrasonic/sonic rotary-hammer drill (USRoHD) is a recent addition to the collection of apparatuses based on ultrasonic/sonic drill corer (USDC). As described below, the USRoHD has several features, not present in a basic USDC, that increase efficiency and provide some redundancy against partial failure. USDCs and related apparatuses were conceived for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. They have been described in numerous previous NASA Tech Briefs articles. To recapitulate: A USDC can be characterized as a lightweight, lowpower, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. A basic USDC includes a piezoelectric stack, an ultrasonic transducer horn connected to the stack, a free mass ( free in the sense that it can bounce axially a short distance between hard stops on the horn and the bit), and a tool bit. The piezoelectric stack creates ultrasonic vibrations that are mechanically amplified by the horn. The bouncing of the free mass between the hard stops generates the sonic vibrations. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that unlike in conventional twist drilling, little applied axial force is needed to make the apparatus advance into the material of interest. There are numerous potential applications for USDCs and related apparatuses in geological exploration on Earth and on remote planets. In early USDC experiments, it was observed that accumulation of cuttings in a drilled hole causes the rate of penetration of the USDC to decrease steeply with depth, and that the rate of penetration can be increased by removing the cuttings. The USRoHD concept provides for

Mid-infrared pulsed laser ultrasonic testing for carbon fiber reinforced plastics.

Science.gov (United States)

Kusano, Masahiro; Hatano, Hideki; Watanabe, Makoto; Takekawa, Shunji; Yamawaki, Hisashi; Oguchi, Kanae; Enoki, Manabu

2018-03-01

Laser ultrasonic testing (LUT) can realize contactless and instantaneous non-destructive testing, but its signal-to-noise ratio must be improved in order to measure carbon fiber reinforced plastics (CFRPs). We have developed a mid-infrared (mid-IR) laser source optimal for generating ultrasonic waves in CFRPs by using a wavelength conversion device based on an optical parametric oscillator. This paper reports a comparison of the ultrasonic generation behavior between the mid-IR laser and the Nd:YAG laser. The mid-IR laser generated a significantly larger ultrasonic amplitude in CFRP laminates than a conventional Nd:YAG laser. In addition, our study revealed that the surface epoxy matrix of CFRPs plays an important role in laser ultrasonic generation. Copyright © 2017 Elsevier B.V. All rights reserved.

Gas ultrasonic flow rate measurement through genetic-ant colony optimization based on the ultrasonic pulse received signal model

International Nuclear Information System (INIS)

Hou, Huirang; Zheng, Dandan; Nie, Laixiao

2015-01-01

For gas ultrasonic flowmeters, the signals received by ultrasonic sensors are susceptible to noise interference. If signals are mingled with noise, a large error in flow measurement can be caused by triggering mistakenly using the traditional double-threshold method. To solve this problem, genetic-ant colony optimization (GACO) based on the ultrasonic pulse received signal model is proposed. Furthermore, in consideration of the real-time performance of the flow measurement system, the improvement of processing only the first three cycles of the received signals rather than the whole signal is proposed. Simulation results show that the GACO algorithm has the best estimation accuracy and ant-noise ability compared with the genetic algorithm, ant colony optimization, double-threshold and enveloped zero-crossing. Local convergence doesn’t appear with the GACO algorithm until –10 dB. For the GACO algorithm, the converging accuracy and converging speed and the amount of computation are further improved when using the first three cycles (called GACO-3cycles). Experimental results involving actual received signals show that the accuracy of single-gas ultrasonic flow rate measurement can reach 0.5% with GACO-3 cycles, which is better than with the double-threshold method. (paper)

Enhancement of biogas production in anaerobic co-digestion by ultrasonic pretreatment

International Nuclear Information System (INIS)

Zou, Shuzhen; Wang, Xiaojiao; Chen, Yuanlin; Wan, Haiwen; Feng, Yongzhong

2016-01-01

Highlights: • Ultrasonic pretreatment changed physical structure of samples. • Ultrasonic pretreatment improved biogas production via changing environment before and during anaerobic digestion process. • The main factors affecting biogas production differ in different pretreated samples. - Abstract: This paper optimized the anaerobic digestion (AD) pretreatment process and identified the influence of pretreatment on the co-digestion of maize straw (MS) and dairy manure (DM). In the study, ultrasonic was used to pretreat MS and DM prior to digestion, with power intensities of 0, 189.39, 284.09, and 378.79 kJ at 0, 20, 30, and 40 min, respectively. Changes in the surface structures of MS and DM were observed by scanning electron microscopy (SEM), and factor analysis was used to analyze the main factors affecting biogas production in the AD process. The result showed that the structure of DM was distributed and that the structure of MS became more roughness following the ultrasonic pretreatment (UP). The highest total biogas production of co-digestion (240.32 mL/g VS_f_e_d) was obtained when MS was pretreated for 30 min without DM pretreatment (MS_3_0DM_0). This was significantly higher than that of the untreated sample (CK) (141.65 mL/g VS_f_e_d). The cellulose activity (CA), reducing sugar (RS) content, volatile fatty acid (VFA) content and pH in the digester feed, and their maximum and minimum values in the AD process was affected by UP. Factor 1 of MS_3_0DM_0 was determined by RS content, pH and VFA content that they had the most influence on biogas production on days 6, 18, 24 and 30. Factor 2 of it was determined by CA, and it had most influence on days 0, 12, 36 and 42 in the AD process, The result of the factor analysis indicated that the main factors affecting biogas production were affected by UP and they differ according to the different digestion stages. This research concluded that UP improved total biogas production via changing the initial

Cold priming drives the sub-cellular antioxidant systems to protect photosynthetic electron transport against subsequent low temperature stress in winter wheat

DEFF Research Database (Denmark)

Li, Xiangnan; Cai, Jian; Liu, Fulai

2014-01-01

Low temperature seriously depresses the growth of wheat through inhibition of photosynthesis, while earlier cold priming may enhance the tolerance of plants to subsequent low temperature stress. Here, winter wheat plants were firstly cold primed (5.2°C lower temperature than the ambient temperatu......-cellular antioxidant systems, depressing the oxidative burst in photosynthetic apparatus, hereby enhanced the tolerance to subsequent low temperature stress in winter wheat plants.......Low temperature seriously depresses the growth of wheat through inhibition of photosynthesis, while earlier cold priming may enhance the tolerance of plants to subsequent low temperature stress. Here, winter wheat plants were firstly cold primed (5.2°C lower temperature than the ambient temperature......, viz., 10.0°C) at the Zadoks growth stage 28 (i.e.re-greening stage, starting on 20th of March) for 7d, and after 14d of recovery the plants were subsequently subjected to a 5d low temperature stress (8.4°C lower than the ambient temperature, viz., 14.1°C) at the Zadoks growth stage 31 (i...

Ultrasonic leak detection

International Nuclear Information System (INIS)

Murphy, R.V.

1977-01-01

A scanning ultrasonic microphone was used to detect the presence and locate the sources of hydraulic noises in piping systems in a reactor environment. The intensity changes of the noises correspond to changes of flow conditions within the system caused by throttled valves, flow rate changes, and leaks. (author)

STUDY ON MORPHOLOGICAL AND STRUCTURAL CHANGES INDUCED BY ULTRASONIC DEGR EASING OF WOOL AND HUMAN HAIR WASTES

Directory of Open Access Journals (Sweden)

BĂLĂU MÎNDRU Tudorel

2014-05-01

Full Text Available Recovery and reuse of wool and hair waste is a challenge with the ultimate goal environment protection. One of the early stages of the recovery process is the operation of scouring-degreasing wool and human hair waste. In recent decades the use of ultrasound technology has established an important place in different industrial processes and has started to revolutionize environmental protection. The power of ultrasound can enhance a wide variety of chemical and physical processes, mainly due to the phenomenon known as cavitation in a liquid medium. The objective of the present work is to develop eco-friendly effective degreasing system for keratin fiber waste with the aid of ultrasound, using distilled water and also trichlorethylene as a medium of propagation-degreasing, and realized a comparative analysis of efficiency of fat extraction by Soxhlet classical method and via ultrasonication. This work investigate the effect that ultrasonic irradiation has on the structure of wool and hair fibers. Thus were highlighted both morphological and structural changes of treated materials using optical microscopy, and FTIR spectroscopy. By using the unconventional method of cleaning and degreasing with an ultrasonic resonator tube are possible reductions in utility and solvents consumption together with changes in the cuticular layer of wool and hair fibers.

System of acquisition and analysis of ultrasonic data

International Nuclear Information System (INIS)

Vaubert, Y.; Birac, A.M.; Saglio, R.

1982-08-01

An original system of acquisition and analysis of ultrasonic data collected during examinations named STADUS-PRODUS has been developed by C.E.A. in Saclay. First developed for the needs of in-service inspection of PWR vessels, it is now used for the different automatic ultrasonic controls with various tools

Effect of Heat Generation of Ultrasound Transducer on Ultrasonic Power Measured by Calorimetric Method

Science.gov (United States)

Uchida, Takeyoshi; Kikuchi, Tsuneo

2013-07-01

Ultrasonic power is one of the key quantities closely related to the safety of medical ultrasonic equipment. An ultrasonic power standard is required for establishment of safety. Generally, an ultrasonic power standard below approximately 20 W is established by the radiation force balance (RFB) method as the most accurate measurement method. However, RFB is not suitable for high ultrasonic power because of thermal damage to the absorbing target. Consequently, an alternative method to RFB is required. We have been developing a measurement technique for high ultrasonic power by the calorimetric method. In this study, we examined the effect of heat generation of an ultrasound transducer on ultrasonic power measured by the calorimetric method. As a result, an excessively high ultrasonic power was measured owing to the effect of heat generation from internal loss in the transducer. A reference ultrasound transducer with low heat generation is required for a high ultrasonic power standard established by the calorimetric method.

Effect of Discontinuous Ultrasonic Treatment on Mechanical Properties and Microstructure of Cast Al413-SiCnp Nanocomposites

Directory of Open Access Journals (Sweden)

M.R. Dehnavi

2015-05-01

Full Text Available Effects of discontinuous ultrasonic treatment on the microstructure, nanoparticle distribution, and mechanical properties of cast Al413-SiCnp nanocomposites were studied. The results showed that discontinuous ultrasonic treatment was more effective in improving the mechanical properties of the cast nanocomposites than the equally timed continuous treatment. The yield and ultimate tensile strengths of Al413-2%SiCnp nanocomposites discontinuously treated for two 20 minute periods increased by about 126% and 100% compared to those of the monolithic sample, respectively. These improvements were about 107% and 94% for the nanocomposites continuously treated for a single 40 minute period. The improvement in the mechanical properties was associated with severe refinement of the microstructure, removal of the remaining gas layers on the particles surfaces, more effective fragmentation of the remaining agglomerates as well as improved wettability and distribution of the reinforcing particles during the first stage of solidification.

Ultrasonically enhanced disintegration. Polymers, sludge, and contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Groenroos, A.

2010-05-15

There are a great variety of potential applications of high-intensity ultrasonic energy. Of these, cleaning, plastic pounding, and at present also sludge disintegration and the remediation of contaminated soil are probably the best known and offer the most general market for high-intensity ultrasonics. All developments within the area of ultrasound applications lead to the creation of environmentally friendly processes and compounds, emphasizing the role of ultrasound in 'green chemistry'. Ultrasound technology is considered not easy to use in industrial processes, since devices providing high sonic energy are not easy to construct. This thesis investigates on a semi-pilot scale if it is possible to enhance the disintegration of three quite different samples: polymers, sludge, and contaminated soil by using ultrasound. The results indicate that it is possible to enhance the disintegration of polymers by means of ultrasonic power only when the cavitation threshold is exceeded. Above the cavitation threshold, the most extensive degradation took place at the lowest ultrasonic frequency used. The biggest decrease (from 115,000 g/mol to 30,000 g/mol) in relative molecular mass (RMM) was observed when the concentration of polyvinyl alcohol (PVA) was the lowest (1.0%). However, in the case of carboxymethylcellulose (CMC) it was observed that when viscosity was not adjusted there is an optimum polymer concentration (1.5-2.0%) where degradation is most efficient. The thesis shows that the extent of ultrasonic depolymerization decreases with decreasing molecular mass of the CMC polymer. The study also reveals that ultrasonic irradiation causes narrowing of the molecular mass distribution. The degradation of CMC polymer proceeded linearly and the rate of ultrasonic depolymerization decreased with decreasing molecular mass. In cases where the initial dynamic viscosities of polymer solutions were not the same, the sonolytic degradation of CMC polymer mainly depended

Characteristic analysis of a traveling wave ultrasonic motor using an ellipsoidal static contact model

International Nuclear Information System (INIS)

Lim, Jung Pil; Rho, Jong Seok; Yi, Kyung Pyo; Jung, Hyun Kyo; Seo, Jung Moo

2009-01-01

A characteristic analysis of an ultrasonic motor (USM) at the design stage has thus far been impossible. Therefore, a characteristic analysis method is suggested on the basis of a proposed model describing the complex nonlinear contact condition between the rotor and stator. The proposed contact model and analysis method can guide theoretical research on the minimization of the main disadvantages of the USM, which mainly result from the contact mechanism. The validity and usefulness of the suggested analysis method is verified by experimental data from a prototyped USM

Absorption and dispersion of ultrasonic waves

CERN Document Server

Herzfeld, Karl F; Massey, H S W; Brueckner, Keith A

1959-01-01

Absorption and Dispersion of Ultrasonic Waves focuses on the influence of ultrasonics on molecular processes in liquids and gases, including hydrodynamics, energy exchange, and chemical reactions. The book first offers information on the Stokes-Navier equations of hydrodynamics, as well as equations of motion, viscosity, formal introduction of volume viscosity, and linearized wave equation for a nonviscous fluid. The manuscript then ponders on energy exchange between internal and external degrees of freedom as relaxation phenomenon; effect of slow energy exchange on sound propagation; differe

Characterization methods for ultrasonic test systems

International Nuclear Information System (INIS)

Busse, L.J.; Becker, F.L.; Bowey, R.E.; Doctor, S.R.; Gribble, R.P.; Posakony, G.J.

1982-07-01

Methods for the characterization of ultrasonic transducers (search units) and instruments are presented. The instrument system is considered as three separate components consisting of a transducer, a receiver-display, and a pulser. The operation of each component is assessed independently. The methods presented were chosen because they provide the greatest amount of information about component operation and were not chosen based upon such conditions as cost, ease of operation, field implementation, etc. The results of evaluating a number of commercially available ultrasonic test instruments are presented

A capacitive ultrasonic transducer based on parametric resonance.

Science.gov (United States)

Surappa, Sushruta; Satir, Sarp; Levent Degertekin, F

2017-07-24

A capacitive ultrasonic transducer based on a parametric resonator structure is described and experimentally demonstrated. The transducer structure, which we call capacitive parametric ultrasonic transducer (CPUT), uses a parallel plate capacitor with a movable membrane as part of a degenerate parametric series RLC resonator circuit with a resonance frequency of f o . When the capacitor plate is driven with an incident harmonic ultrasonic wave at the pump frequency of 2f o with sufficient amplitude, the RLC circuit becomes unstable and ultrasonic energy can be efficiently converted to an electrical signal at f o frequency in the RLC circuit. An important characteristic of the CPUT is that unlike other electrostatic transducers, it does not require DC bias or permanent charging to be used as a receiver. We describe the operation of the CPUT using an analytical model and numerical simulations, which shows drive amplitude dependent operation regimes including parametric resonance when a certain threshold is exceeded. We verify these predictions by experiments with a micromachined membrane based capacitor structure in immersion where ultrasonic waves incident at 4.28 MHz parametrically drive a signal with significant amplitude in the 2.14 MHz RLC circuit. With its unique features, the CPUT can be particularly advantageous for applications such as wireless power transfer for biomedical implants and acoustic sensing.

Signal analysis approach to ultrasonic evaluation of diffusion bond quality

International Nuclear Information System (INIS)

Thomas, Graham; Chinn, Diane

1999-01-01

Solid state bonds like the diffusion bond are attractive techniques for joining dissimilar materials since they are not prone to the defects that occur with fusion welding. Ultrasonic methods can detect the presence of totally unbonded regions but have difficulty sensing poor bonded areas where the substrates are in intimate contact. Standard ultrasonic imaging is based on amplitude changes in the signal reflected from the bond interface. Unfortunately, amplitude alone is not sensitive to bond quality. We demonstrated that there is additional information in the ultrasonic signal that correlates with bond quality. In our approach, we interrogated a set of dissimilar diffusion bonded samples with broad band ultrasonic signals. The signals were digitally processed and the characteristics of the signals that corresponded to bond quality were determined. These characteristics or features were processed with pattern recognition algorithms to produce predictions of bond quality. The predicted bond quality was then compared with the destructive measurement to assess the classification capability of the ultrasonic technique

Cold plate

Energy Technology Data Exchange (ETDEWEB)

Marroquin, Christopher M.; O' Connell, Kevin M.; Schultz, Mark D.; Tian, Shurong

2018-02-13

A cold plate, an electronic assembly including a cold plate, and a method for forming a cold plate are provided. The cold plate includes an interface plate and an opposing plate that form a plenum. The cold plate includes a plurality of active areas arranged for alignment over respective heat generating portions of an electronic assembly, and non-active areas between the active areas. A cooling fluid flows through the plenum. The plenum, at the non-active areas, has a reduced width and/or reduced height relative to the plenum at the active areas. The reduced width and/or height of the plenum, and exterior dimensions of cold plate, at the non-active areas allow the non-active areas to flex to accommodate surface variations of the electronics assembly. The reduced width and/or height non-active areas can be specifically shaped to fit between physical features of the electronics assembly.

Quality assurance of brazed copper plates through advanced ultrasonic NDE

OpenAIRE

Segreto, T.; Caggiano, A.; Teti, R.

2016-01-01

Ultrasonic non-destructive methods have demonstrated great potential for the detection of flaws in a material under examination. In particular, discontinuities produced by welding, brazing, and soldering are regularly inspected through ultrasonic techniques. In this paper, an advanced ultrasonic non-destructive evaluation technique is applied for the quality control of brazed copper cells in order to realize an accelerometer prototype for cancer proton therapy. The cells are composed of two h...

Manufacturing technologies for ultrasonic transducers in a broad frequency range

OpenAIRE

Gebhardt, Sylvia; Hohlfeld, Kai; Günther, Paul; Neubert, Holger

2018-01-01

According to the application field, working frequency of ultrasonic transducers needs to be tailored to a certain value. Low frequency ultrasonic transducers with working frequencies of 1 kHz to 1 MHz are especially interesting for sonar applications, whereas high frequency ultrasonic transducers with working frequencies higher than 15 MHz are favorable for high-resolution imaging in biomedical and non-destructive evaluation. Conventional non-destructive testing devices and clinical ultrasoun...

Microbiological evaluation of ultrasonic nebulization for disinfecting dental impressions.

Science.gov (United States)

Mendonca, Marcio Jose; Rafael, Renata Santos; Camilotti, Veridiana; Menolli, Rafael Andrade; Sicoli, Eliseu Augusto; Teixeira, Nancielli; Sinhoreti, Mario Alexandre Coelho

2013-07-01

Disinfecting dental impressions is necessary to decrease the risk of cross-contamination in dental offices. Ultrasonic nebulization has been mentioned as a microbicidal technique that can be used to disinfect contaminated dental impressions. This study compared the microbicidal effect of 2% glutaraldehyde and 0.2% peracetic acid for the disinfection of dental impressions made with vinyl polysiloxane, using 2 disinfection methods: immersion and ultrasonic nebulization. Bactericial efficacy was examined using Staphylococcus aureus and Bacillus atrophaeus as indicators. Thirty impressions were obtained and distributed randomly in 5 groups (n = 6). Group 1 was immersed in 2% glutaraldehyde immersion for 10 minutes, Group 2 was immersed in 0.2% peracetic acid for 10 minutes, Group 3 underwent ultrasonic nebulization for 10 minutes in 2% glutaraldehyde solution, Group 4 underwent ultrasonic nebulization for 10 minutes in 0.2% peracetic acid solution, and Group 5 was a control group that received no disinfectant. Both solutions experienced a 100% reduction in microorganisms following ultrasonic nebulization, as did peracetic acid following immersion; however, immersion in glutaraldehyde demonstrated lower values of reduction in B atrophaeus group, with a statistically significant difference compared with the other experimental groups.

Elastic-Plastic Behaviour of Ultrasonic Assisted Compression of Polyvinyl Chloride (PVC) Foam

Science.gov (United States)

Muhalim, N. A. D.; Hassan, M. Z.; Daud, Y.

2018-04-01

The present study aims to investigate the elastic-plastic behaviour of ultrasonic assisted compression of PVC closed-cell foam. A series of static and ultrasonic compression test of PVC closed-cell foam were conducted at a constant cross head speed of 30 mm/min on dry surface condition. For quasi-static test, specimen was compressed between two rigid platens using universal testing machine. In order to evaluate the specimen behavior under ultrasonic condition, specimen was placed between a specifically design double-slotted block horn and rigid platen. The horn was designed and fabricated prior to the test as a medium to transmit the ultrasonic vibration from the ultrasonic transducer to the working specimen. It was tuned to a frequency of 19.89 kHz in longitudinal mode and provided an average oscillation amplitude at 6 µm on the uppermost surface. Following, the characteristics of stress-strain curves for quasi-static and ultrasonic compression tests were analyzed. It was found that the compressive stress was significantly reduced at the onset of superimposed ultrasonic vibration during plastic deformation.

Development of automatic ultrasonic testing system and its application

International Nuclear Information System (INIS)

Oh, Sang Hong; Matsuura, Toshihiko; Iwata, Ryusuke; Nakagawa, Michio; Horikawa, Kohsuke; Kim, You Chul

1997-01-01

The radiographic testing (RT) has been usually applied to a nondestructive testing, which is carried out on purpose to detect internal defects at welded joints of a penstock. In the case that RT could not be applied to, the ultrasonic testing (UT) was performed. UT was generally carried out by manual scanning and the inspections data were recorded by the inspector in a site. So, as a weak point, there was no objective inspection records correspond to films of RT. It was expected that the automatic ultrasonic testing system by which automatic scanning and automatic recording are possible was developed. In this respect, the automatic ultrasonic testing system was developed. Using newly developed the automatic ultrasonic testing system, test results to the circumferential welded joints of the penstock at a site were shown in this paper.

Study of ultrasonic imagine of spleen in patients with leukemia

International Nuclear Information System (INIS)

Zheng Hui; Zhou Chunyan; Jiang Ju; Luo Liying; Huang Yanhong

2011-01-01

To investigate spleen ultrasonic imagine in patients with leukemia and to provide basis information for preventing and treat disease,the spleens imaging of 158 patients with leukemia were detected by B mode ultrasonicgraphy and the data of clinical medical examination were analyzed.The results showed that the spleens' ultrasonic imagine of patients with leukemia were not related to the degree of anemia.The ultrasonic imagines of spleen in patients with chronic leukemia were different to the other kinds of leukemia.The ultrasonic imagine of spleens in leukemia patients are related to types and development of leukemia.The B-ultrasound screening should be used to help clinical diagnosis and treatment of patients with leukemia. (authors)

First stage of bio-jet fuel production: non-food sunflower oil extraction using cold press method

Directory of Open Access Journals (Sweden)

Xianhui Zhao

2014-06-01

Full Text Available As a result of concerning petroleum price increasing and environmental impact, more attention is attracted to renewable resources for transportation fuels. Because not conflict with human and animal food resources, non-food vegetable oils are promising sources for developing bio-jet fuels. Extracting vegetable oil from oilseeds is the first critical step in the pathway of bio-jet fuel production. When sunflower seeds are de-hulled, there are always about 5%–15% broken seed kernels (fine meat particles left over as residual wastes with oil content up to 48%. However, the oil extracted from these sunflower seed residues is non-edible due to its quality not meeting food standards. Genetically modified sunflower grown on margin lands has been identified one of sustainable biofuel sources since it doesn't compete to arable land uses. Sunflower oils extraction from non-food sunflower seeds, sunflower meats, and fine sunflower meats (seed de-hulling residue was carried out using a cold press method in this study. Characterization of the sunflower oils produced was performed. The effect of cold press rotary frequency on oil recovery and quality was discussed. The results show that higher oil recovery was obtained at lower rotary frequencies. The highest oil recovery for sunflower seeds, sunflower meats, and fine sunflower meats in the tests were 75.67%, 89.74% and 83.19% respectively. The cold press operating conditions had minor influence on the sunflower oil quality. Sunflower meat oils produced at 15 Hz were preliminarily upgraded and distilled. The properties of the upgraded sunflower oils were improved. Though further study is needed for the improvement of processing cost and oil recovery, cold press has shown promising to extract oil from non-food sunflower seeds for future bio-jet fuel production.

Cold-water coral mounds on the Pen Duick Escarpment, Gulf of Cadiz: The MiCROSYSTEMS project approach

NARCIS (Netherlands)

Van Rooij, D.; Blamart, D.; De Mol, L.; Mienis, F.; Pirlet, H.; Wehrmann, L. M.; Barbieri, R.; Maignien, L.; Templer, S. P.; de Haas, H.; Hebbeln, D.; Frank, N.; Larmagnat, S.; Stadnitskaia, A.; Stivaletta, N.; van Weering, T.; Zhang, Y.; Hamoumi, N.; Cnudde, V.; Duyck, P.; Henriet, J.-P.; The MiCROSYSTEMS MD 169 Shipboard Party

2011-01-01

Here we present a case study of three cold-water coral mounds in a juvenile growth stage on top of the Pen Duick Escarpment in the Gulf of Cadiz; Alpha, Beta and Gamma mounds. Although cold-water corals are a common feature on the adjacent cliffs, mud volcanoes and open slope, no actual living

Pre and post garter spring repositioning ultrasonic inspection of pressure tubes

International Nuclear Information System (INIS)

Desimone, C.; Katchadjian, P.; Tacchia, Mauricio

1997-01-01

This paper present a description of the ultrasonic cracked hydride blister detections system used for pre and post inspection of pressure tubes during garter spring repositioning in CNE (Embalse Nuclear Power Station). Ultrasonic system setup configuration, transducers characteristics, blister detection head, calibration of parameters, operating procedure, records of ultrasonic inspections and evaluation. (author) [es

Performance demonstration experience for reactor pressure vessel shell ultrasonic testing

International Nuclear Information System (INIS)

Zado, V.

1998-01-01

The most ultrasonic testing techniques used by many vendors for pressurized water reactor (PWR) examinations were based on American Society of Mechanical Engineers 'Boiler and Pressurized Vessel Code' (ASME B and PV Code) Sections XI and V. The Addenda of ASME B and PV Code Section XI, Edition 1989 introduced Appendix VIII - 'Performance Demonstration for Ultrasonic Examination Systems'. In an effort to increase confidence in performance of ultrasonic testing of the operating nuclear power plants in United States, the ultrasonic testing performance demonstration examination of reactor vessel welds is performed in accordance with Performance Demonstration Initiative (PDI) program which is based on ASME Code Section XI, Appendix VIII requirements. This article provides information regarding extensive qualification preparation works performed prior EPRI guided performance demonstration exam of reactor vessel shell welds accomplished in January 1997 for the scope of Appendix VIII, Supplements IV and VI. Additionally, an overview of the procedures based on requirements of ASME Code Section XI and V in comparison to procedure prepared for Appendix VIII examination is given and discussed. The samples of ultrasonic signals obtained from artificial flaws implanted in vessel material are presented and results of ultrasonic testing are compared to actual flaw sizes. (author)

Evaluation of ultrasonic technique to characterize the concentration of boric acid in liquid medium

International Nuclear Information System (INIS)

Kohara, Richard Yuzo Ramida

2015-01-01

This dissertation is to analyze the viability of using ultrasonic technique to characterize the concentration of boric acid in liquid medium non-invasively, therefore, ultrasonic tests were performed relating different boric acid concentrations with the travel time of the ultrasonic wave, also were evaluated factors able to mask the characterization of these concentrations by ultrasonic technique. The results showed that the ultrasonic technique allows the characterization of boric acid concentrations in liquid medium in very simple terms by the ultrasonic wave travel time, requiring further studies in complex conditions. (author)

Contribution of dynamic focusing to ultrasonic defect characterization

International Nuclear Information System (INIS)

Mahaut, S.

1997-01-01

Non destructive testing of vessels of pressurized water reactors uses ultrasonic focused transducers, with spherically shaped emitting surface or requiring an acoustic lens. But a mechanically focused transducer has to be used for a given inspection zone and for a fixed control configuration. The aim of this thesis is to improve ultrasonic defect characterization using adaptive dynamic focusing. Such a technique makes use of a ultrasonic defect characterization using adaptive dynamic focusing. Such a technique makes use of an ultrasonic transducer split into an array of individually controlled elements, allowing to apply delay and amplitude laws, calculated from modeling or experimentally deduced. Acoustical characteristics of the ultrasonic beam in the inspected specimen this can be electronically controlled; refraction angle, depth focusing, beam width. We briefly describe in the first chapter a theoretical modeling of the ultrasonic field radiated through a fluid/solid interface, extended to phase array transducers. This model is based on the integral formulation of Rayleigh, modified to take into account transmission through a fluid/solid (homogeneous and isotropic), of planar or cylindrical shape. In the second chapter an experimental study of this technique, with delay and amplitude laws given from the model, is presented, showing the efficiency of this method to adjust the acoustic performances. In he third chapter, experimental delay laws, extracted from the time distribution of signals received by the array (issued from a preliminary detected reflector), are used to provide an optimal imaging of the defect. This self-focusing procedure shows to adapt to a defect without using theoretical delays. The last chapter is dedicated to different applications devoted to improved defect characterization. The first application uses amplitude distribution received by the array, pointing out geometric characteristics of the reflector, while the second application

A new deconvolution method applied to ultrasonic images

International Nuclear Information System (INIS)

Sallard, J.

1999-01-01

This dissertation presents the development of a new method for restoration of ultrasonic signals. Our goal is to remove the perturbations induced by the ultrasonic probe and to help to characterize the defects due to a strong local discontinuity of the acoustic impedance. The point of view adopted consists in taking into account the physical properties in the signal processing to develop an algorithm which gives good results even on experimental data. The received ultrasonic signal is modeled as a convolution between a function that represents the waveform emitted by the transducer and a function that is abusively called the 'defect impulse response'. It is established that, in numerous cases, the ultrasonic signal can be expressed as a sum of weighted, phase-shifted replicas of a reference signal. Deconvolution is an ill-posed problem. A priori information must be taken into account to solve the problem. The a priori information translates the physical properties of the ultrasonic signals. The defect impulse response is modeled as a Double-Bernoulli-Gaussian sequence. Deconvolution becomes the problem of detection of the optimal Bernoulli sequence and estimation of the associated complex amplitudes. Optimal parameters of the sequence are those which maximize a likelihood function. We develop a new estimation procedure based on an optimization process. An adapted initialization procedure and an iterative algorithm enables to quickly process a huge number of data. Many experimental ultrasonic data that reflect usual control configurations have been processed and the results demonstrate the robustness of the method. Our algorithm enables not only to remove the waveform emitted by the transducer but also to estimate the phase. This parameter is useful for defect characterization. At last the algorithm makes easier data interpretation by concentrating information. So automatic characterization should be possible in the future. (author)

Evaluation of Fall Sowing of Cold Tolerant Chickpa (Cicer arietinum L. Genotypes under Supplementary Irrigation in Mashhad

Directory of Open Access Journals (Sweden)

A. Nezami

2011-01-01

Full Text Available Abstract In order to investigate of phenological and morphological characteristics, yield components and yield of cold tolerant chickpea genotypes in fall sowing, 9 cold tolerant chickpea genotypes and Karaj 12-60-31 as a control were evaluated in Experimental Field of College of Agriculture, Ferdowsi University of Mashhad in 2006-2007. The experiment was carried out based on randomized complete block design with four replications. The planting date was 25 October and three times of irrigation was done as supplementary irrigation at planting stage, 20 days after that and at flowering stage. The control was ruined at seedling stage due to the hard cold. Based on the results, the differences among the genotypes for all of measured traits including growth duration, plant height, number and length of branches, yield components (pod number per plant, seed number per pod and 100 seeds weight, seed yield and biological yield were significant (P≥0.05. There were positive and significant correlations between seed yield and vegetative (r=0.71** and reproductive (r=0.68** periods. MCC291, MCC349 and MCC207 produced the highest seed yield with 231, 229 and 217 g.m-2, respectively. Totally, it appears that some of genotypes have appropriate yield potential for fall sowing under supplementary irrigation at Mashhad. Keywords: Cold tolerant, Chickpea genotypes, Phenological and morphological characteristics, Seed yield, Yield components

Ultrasonic Ranging System With Increased Resolution

Science.gov (United States)

Meyer, William E.; Johnson, William G.

1987-01-01

Master-oscillator frequency increased. Ultrasonic range-measuring system with 0.1-in. resolution provides continuous digital display of four distance readings, each updated four times per second. Four rangefinder modules in system are modified versions of rangefinder used for automatic focusing in commercial series of cameras. Ultrasonic pulses emitted by system innocuous to both people and equipment. Provides economical solutions to such distance-measurement problems as posed by boats approaching docks, truck backing toward loading platform, runway-clearance readout for tail of airplane with high angle attack, or burglar alarm.

Ultrasonic process for detoxification of groundwater

International Nuclear Information System (INIS)

Wu, Jiann M.; Huang, H.S.; Livengood, C.D.

1991-01-01

In this paper, we present the results of an investigation of the ultrasonic irradiation of carbon tetrachloride at various pH values, temperatures, and power intensities. Kinetic data and selected chemical mechanism are discussed and proposed. To study oxidant efficiency, chemical oxidants, such as hydrogen peroxide, are also considered. This work is part of a project entitled ''Ultrasonic Process for Detoxification of Groundwater and Soil,'' sponsored by the US Department of Energy, Office of Technology Development, to develop an innovative process for the effective destruction of chlorinated organics in soil and groundwater

Ultrasonic Testing of NIF Amplifier FAU Top Plates

International Nuclear Information System (INIS)

Chinn, D.J.; Huber, R.D.; Haskins, J.J.; Rodriguez, J.A.; Souza, P.R.; Le, T.V.

2002-01-01

A key component in the National Ignition Facility (NIF) laser optic system is the amplifier frame assembly unit (FAU). The cast aluminum top plate that supports the FAU is required to withstand loads that would occur during an earthquake with a recurrence period of 1000 years. The stringent seismic requirements placed on the FAU top plate induced a study of the cast aluminum material used in the top plate. Ultrasonic testing was used to aid in characterizing the aluminum material used in the plates. This report documents the work performed using contact ultrasonic testing to characterize the FAU top plate material. The ultrasonic work reported here had 3 objectives: (1) inspect the plate material before cyclic testing conducted at the Pacific Earthquake Engineering Research Center (PEER); (2) determine the overall quality of individual plates; and (3) detect large defects in critical areas of individual plates. Section III, ''Pre-cyclic test inspection'', describes work performed in support of Objective 1. Section IV, ''Ultrasonic field measurements'', describes work performed in support of Objectives 2 and 3

Methanolysis of triolein by low frequency ultrasonic irradiation

Energy Technology Data Exchange (ETDEWEB)

Hanh, Hoang Duc; Starvarache, Carmen; Okitsu, Kenji; Maeda, Yasuaki; Nishimura, Rokuro [Graduate School of Engineering, Osaka Prefecture University, Gakuen-cho 1-1, Sakai, Osaka 599-8531 (Japan); Dong, Nguyen The [Institute of Environmental Technology, Vietnamese Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi (Viet Nam)

2008-02-15

Methanolysis of triolein was investigated at room temperature by 40 kHz ultrasonic irradiation to make biodiesel fuel as methyl esters. It was found that the yield of methyl esters strongly depended on the amount of KOH and the molar ratio of methanol to triolein (M/T) and was highest at the M/T molar ratio of 6/1, KOH concentration of 1 wt% and irradiation time of 30 min. In addition, the effects of sonication on the methanolysis of triolein were discussed in comparison to the effects of stirring experiments. The optimum condition under stirring experiments showed that the molar ratio of M/T, KOH concentration and reaction time were 6/1, 1.5 wt% and 4 h, respectively. These results clearly indicated that the ultrasonic irradiation method would be a promising one compared to the conventional stirring method. The high yield under the ultrasonic irradiation condition would be due to high speed mixing and mass transfer between the methanol and triolein as well as the formation of a microemulsion resulting from the ultrasonic cavitation phenomenon. (author)

Methanolysis of triolein by low frequency ultrasonic irradiation

Energy Technology Data Exchange (ETDEWEB)

Hoang Duc Hanh [Graduate School of Engineering, Osaka Prefecture University, Gakuen-cho 1-1, Sakai, Osaka 599-8531 (Japan)], E-mail: hoangduchanh75@yahoo.com; Nguyen The Dong [Institute of Environmental Technology, Vietnamese Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi (Viet Nam); Starvarache, Carmen; Okitsu, Kenji; Maeda, Yasuaki; Nishimura, Rokuro [Graduate School of Engineering, Osaka Prefecture University, Gakuen-cho 1-1, Sakai, Osaka 599-8531 (Japan)

2008-02-15

Methanolysis of triolein was investigated at room temperature by 40 kHz ultrasonic irradiation to make biodiesel fuel as methyl esters. It was found that the yield of methyl esters strongly depended on the amount of KOH and the molar ratio of methanol to triolein (M/T) and was highest at the M/T molar ratio of 6/1, KOH concentration of 1 wt% and irradiation time of 30 min. In addition, the effects of sonication on the methanolysis of triolein were discussed in comparison to the effects of stirring experiments. The optimum condition under stirring experiments showed that the molar ratio of M/T, KOH concentration and reaction time were 6/1, 1.5 wt% and 4 h, respectively. These results clearly indicated that the ultrasonic irradiation method would be a promising one compared to the conventional stirring method. The high yield under the ultrasonic irradiation condition would be due to high speed mixing and mass transfer between the methanol and triolein as well as the formation of a microemulsion resulting from the ultrasonic cavitation phenomenon.

Development of ultrasonic instrument 'UT1000 Series'

International Nuclear Information System (INIS)

Ogura, Yukio; Ikeda, Toshimichi

1984-01-01

The ultrasonic flaw detectors with 'A-scope indication' have been frequently used as the means for confirming the soundness of structures and equipments, but there are problems in their operational, quantifying and recording capabilities. Recently, the digital ultrasonic measuring instrument of touch panel type ''UT 1000 Series'' has been developed, which resolves these problems by a single effort. This measuring instrument is that of portable type, which gives the digital output of measured results in real time only by lightly touching the peak point of an echo on the Brown tube. This instrument contains the rich software for measurement, and can measure the positions and dimensions of defects and the pressure on contact surfaces with high accuracy. 'A-scope indication' is the indication with an oscilloscope taking the intensity of echo and the propagation time of ultrasonic waves on the ordinate and abscissa, respectively. There are three types of the instrument, that is, for detecting defects, for measuring contact surface pressure and for both purposes. The size of the instrument is 240 mm width, 350 mm length and 175 mm height, and the weight is 8.5 kgf. The specification, function and features of the ultrasonic flaw detector, touch panel, gain setter, key board, microcomputer and others are reported. (Kako, I.)

Design - manufacturing and characterization of specific ultrasonic probes

International Nuclear Information System (INIS)

Petit, J.

1985-01-01

Optimization of ultrasonic examinations requires essentially to determine precisely parameters used for manufacturing of probes and to check characteristics of beams used. The system presented permits an automatic determination of dimensions of beams in conditions which are totally representative of those of their use. In the field of ultrasonic examinations a good estimate or knowledge of sound beams is of great help to solve difficult examination problems. The FRAMATOME's Centre d'Etude et de Recherche en Essais Non Destructifs (CEREND) : (Study and Research Center in Non-Destructive Testing) has developed and elaborated various techniques in order to improve ultrasonic examinations with specific probes. These techniques concern design, manufacturing and characterization of these probes

A Simple Model for Nonlinear Confocal Ultrasonic Beams

Science.gov (United States)

Zhang, Dong; Zhou, Lin; Si, Li-Sheng; Gong, Xiu-Fen

2007-01-01

A confocally and coaxially arranged pair of focused transmitter and receiver represents one of the best geometries for medical ultrasonic imaging and non-invasive detection. We develop a simple theoretical model for describing the nonlinear propagation of a confocal ultrasonic beam in biological tissues. On the basis of the parabolic approximation and quasi-linear approximation, the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation is solved by using the angular spectrum approach. Gaussian superposition technique is applied to simplify the solution, and an analytical solution for the second harmonics in the confocal ultrasonic beam is presented. Measurements are performed to examine the validity of the theoretical model. This model provides a preliminary model for acoustic nonlinear microscopy.

Conceptualizing Cold Disasters

DEFF Research Database (Denmark)

Lauta, Kristian Cedervall; Dahlberg, Rasmus; Vendelø, Morten Thanning

2017-01-01

In the present article, we explore in more depth the particular circumstances and characteristics of governing what we call ‘cold disasters’, and thereby, the paper sets out to investigate how disasters in cold contexts distinguish themselves from other disasters, and what the implications hereof...... are for the conceptualization and governance of cold disasters. Hence, the paper can also be viewed as a response to Alexander’s (2012a) recent call for new theory in the field of disaster risk reduction. The article is structured in four overall parts. The first part, Cold Context, provides an overview of the specific...... conditions in a cold context, exemplified by the Arctic, and zooms in on Greenland to provide more specific background for the paper. The second part, Disasters in Cold Contexts, discusses “cold disasters” in relation to disaster theory, in order to, elucidate how cold disasters challenge existing...

Proposed new ultrasonic test bed

International Nuclear Information System (INIS)

Maxfield, B.W.

1978-01-01

Within the last four or five years, a great deal of progress has been made both here and in a number of other laboratories in developing techniques that will enable considerably more information to be obtained from the ultrasonic examination of an object. Some of these recent developments relate to information contained within the diffracted beam which does not return along the incident path. An ultrasonic examination based upon an evaluation of diffracted energy must use at least two transducers, one for transmission and the other for reception. Current indications are that even more reliable test results will be achieved using a receiving transducer that can scan a significant portion of the diffracted field including that portion which is back-reflected. In general, this scan can be interpreted most accurately if it follows a path related to the surface shape. If more than one region within the object is to be interrogated, then the transmitting transducer must also be scanned, again along a path related to the surface shape. The large quantity of information obtained as the result of such an examination must be subjected to sophisticated computer analysis in order to be displayed in a meaningful and intelligible manner. Although one motivation for building such an instrument is to explore new ultrasonic test procedures that are evolving from current laboratory research, this is neither the sole motivation nor the only use for this instrument. Such a mechanical and electronic device would permit conventional ultrasonic tests to be performed on parts of complex geometry without the expensive and time-consuming special fixturing that is currently required. May possible test geometries could be explored in practice prior to the construction of a specialized test apparatus. Hence, it would be necessary to design much, if any, flexibility into the special test apparatus

[The use of ultrasonic files in canal preparation].

Science.gov (United States)

Calas, P; Terrie, B

1990-01-01

The continuous high volume of irrigating solution delivered by the ultrasonic system facilitates the root canal debridement. An excellent cleaning of dentin wall is obtained even on surfaces unreached by the mechanical instrumentation. In order to obtain an efficacious preparation, the use of ultrasonic files were combined with instrumentation. This new technique is described in this article.

Cold fusion method

International Nuclear Information System (INIS)

Takahashi, Akihito.

1994-01-01

A Pt wire electrode is supported from the periphery relative to a Pd electrode by way of a polyethylene or teflon plate in heavy water, and electrolysis is applied while varying conditions successively in a sawteeth fashion at an initial stage, and after elapse of about one week, a pulse current is supplied to promote nuclear reaction and to generate excess heat greater than a charged electric power. That is, small amount of neutron emission is increased and electrolytic cell temperature is elevated by varying the electrolysis conditions successively in the sawteeth fashion at the initial stage. In addition, when the pulse electric current is supplied after elapse of about one week, the electrolytic cell temperature is abnormally elevated, so that the promotion of nuclear reaction phenomenon and the generation of excess heat greater than the charged electric power are recognized. Then, a way to control power level and time fluctuation of cold fusion is attained, thereby contributing to development of a further method for generating excess heat as desired. In addition, it contributes to a development for a method of obtaining such an excess heat that can be taken as a new energy. (N.H.)

An advanced system for automated ultrasonic testing

International Nuclear Information System (INIS)

Dressler, K.

1989-01-01

As the main component of the AUP system, an ALOK ultrasonic unit has been chosen as it allows for testing of large component areas both search for defects and description of defect geometries. All data required for fault analysis can be obtained by one measuring run. For inspection of primary circuit components in nuclear power stations, the manipulator control and the ultrasonic probe are installed behind the first sufficient shielding. (orig./HP) [de

Ultrasonic enhancement of lipase-catalysed transesterification for biodiesel synthesis.

Science.gov (United States)

Bhangu, Sukhvir Kaur; Gupta, Shweta; Ashokkumar, Muthupandian

2017-01-01

The production of biodiesel was carried out from canola oil and methanol catalysed by lipase from Candida rugosa under different ultrasonic experimental conditions using horn (20kHz) and plate (22, 44, 98 and 300kHz) transducers. The effects of experimental conditions such as horn tip diameter, ultrasonic power, ultrasonic frequency and enzyme concentrations on biodiesel yield were investigated. The results showed that the application of ultrasound decreased the reaction time from 22-24h to 1.5h with the use of 3.5cm ultrasonic horn, an applied power of 40W, methanol to oil molar ratio of 5:1 and enzyme concentration of 0.23wt/wt% of oil. Low intensity ultrasound is efficient and a promising tool for the enzyme catalysed biodiesel synthesis as higher intensities tend to inactivate the enzyme and reduce its efficiency. Copyright © 2016 Elsevier B.V. All rights reserved.

High-resolution ultrasonic spectroscopy

Directory of Open Access Journals (Sweden)

V. Buckin

2018-03-01

Full Text Available High-resolution ultrasonic spectroscopy (HR-US is an analytical technique for direct and non-destructive monitoring of molecular and micro-structural transformations in liquids and semi-solid materials. It is based on precision measurements of ultrasonic velocity and attenuation in analysed samples. The application areas of HR-US in research, product development, and quality and process control include analysis of conformational transitions of polymers, ligand binding, molecular self-assembly and aggregation, crystallisation, gelation, characterisation of phase transitions and phase diagrams, and monitoring of chemical and biochemical reactions. The technique does not require optical markers or optical transparency. The HR-US measurements can be performed in small sample volumes (down to droplet size, over broad temperature range, at ambient and elevated pressures, and in various measuring regimes such as automatic temperature ramps, titrations and measurements in flow.

Old World frog and bird vocalizations contain prominent ultrasonic harmonics

Science.gov (United States)

Narins, Peter M.; Feng, Albert S.; Lin, Wenyu; Schnitzler, Hans-Ulrich; Denzinger, Annette; Suthers, Roderick A.; Xu, Chunhe

2004-02-01

Several groups of mammals such as bats, dolphins and whales are known to produce ultrasonic signals which are used for navigation and hunting by means of echolocation, as well as for communication. In contrast, frogs and birds produce sounds during night- and day-time hours that are audible to humans; their sounds are so pervasive that together with those of insects, they are considered the primary sounds of nature. Here we show that an Old World frog (Amolops tormotus) and an oscine songbird (Abroscopus albogularis) living near noisy streams reliably produce acoustic signals that contain prominent ultrasonic harmonics. Our findings provide the first evidence that anurans and passerines are capable of generating tonal ultrasonic call components and should stimulate the quest for additional ultrasonic species.

The Machining of Hard Mold Steel by Ultrasonic Assisted End Milling

Directory of Open Access Journals (Sweden)

Ming Yi Tsai

2016-11-01

Full Text Available This study describes the use of ultrasonic-assisted end milling to improve the quality of the machined surface of hard Stavax (modified AISI 420 mold steel and to reduce the amount of work involved in the final polishing process. The effects of input voltage, the stretch length and cutter holding force on the amplitude of the ultrasonic vibration used were measured. The effect of ultrasonic frequency (25 and 50 kHz and amplitude (0, 2.20 and 3.68 μm as well as the effect of the rake angle (6° and −6° and the cutter helix angle (25°, 35° and 45° on tool wear and quality of the workpiece surface finish were also investigated. It was found that the ultrasonic amplitude increased with cutter stretch length and input voltage, as expected. The amplitude remained constant when the cutter holding force exceeded 15 N. The experimental results showed that the ultrasonic amplitude had an optimum value with respect to surface finish. However, large amplitude ultrasonics did not necessarily improve quality. Furthermore, the cutters used for ultrasonic-assisted milling show less wear than those used for normal milling. It was also found that a positive rake angle and cutters with a large helix angle gave a better surface finish.

Workability and mechanical properties of ultrasonically cast Al–Al2O3 nanocomposites

International Nuclear Information System (INIS)

Mula, Suhrit; Pabi, S.K.; Koch, Carl C; Padhi, P.; Ghosh, S.

2012-01-01

Workability and mechanical properties of the ultrasonically cast Al–X wt% Al 2 O 3 (X=2, 3.57 and 4.69) metal matrix nanocomposites were reported in the present investigation. The Al–Al 2 O 3 (average size ∼10 nm) composites showed maximum reduction ratios of 2, 1.75 and 1.41 at room temperature, and 8, 7 and 6 at 300 °C. The elastic modulus, nanoindentation hardness, microhardness and Vickers hardness were measured on the as-cast, cold and hot rolled specimens. The tensile properties were also evaluated for the as-cast composites for different wt% of reinforcement. The microstructural examination was done by optical, scanning and transmission electron microscopy. The strength and workability of the nanocomposites were discussed in the light of dislocation/particle interaction, particle size and its concentration, inter-particle spacing and working temperature. 2 wt% of Al 2 O 3 reinforcement showed better combination of workability and mechanical properties possibly due to better distribution of particulates in the matrix.

Effects of ultrasonic disintegration on sludge microbial activity and dewaterability

International Nuclear Information System (INIS)

Li Huan; Jin Yiying; Mahar, Rasool Bux; Wang Zhiyu; Nie Yongfeng

2009-01-01

Ultrasonic treatment can disintegrate sludge, enhance microbial activity and improve sludge dewaterability at different energy inputs. To find their relationship, the three phenomena during ultrasonic treatment were investigated synchronously, and an experimental model was established to describe the process of ultrasonic sludge disintegration. Analysis results showed that the changes of sludge microbial activity and dewaterability were dependent on sludge disintegration degree during ultrasonic treatment. When sludge disintegration degree was lower than 20%, sludge flocs were disintegrated into micro-floc aggregates and the microbial activity increased over 20%. When sludge disintegration degree was over 40%, most cells were destroyed at different degree, and sludge activity decreased drastically. Only when sludge disintegration degree was 2-5%, sludge dewaterability was improved with the conditioning of FeCl 3 . It was also found that the sonication with low density and long duration was more efficient than sonication with high density and short duration at the same energy input for sludge disintegration, and a transmutative power function model can be used to describe the process of ultrasonic disintegration

Effects of ultrasonic disintegration on sludge microbial activity and dewaterability.

Science.gov (United States)

Huan, Li; Yiying, Jin; Mahar, Rasool Bux; Zhiyu, Wang; Yongfeng, Nie

2009-01-30

Ultrasonic treatment can disintegrate sludge, enhance microbial activity and improve sludge dewaterability at different energy inputs. To find their relationship, the three phenomena during ultrasonic treatment were investigated synchronously, and an experimental model was established to describe the process of ultrasonic sludge disintegration. Analysis results showed that the changes of sludge microbial activity and dewaterability were dependent on sludge disintegration degree during ultrasonic treatment. When sludge disintegration degree was lower than 20%, sludge flocs were disintegrated into micro-floc aggregates and the microbial activity increased over 20%. When sludge disintegration degree was over 40%, most cells were destroyed at different degree, and sludge activity decreased drastically. Only when sludge disintegration degree was 2-5%, sludge dewaterability was improved with the conditioning of FeCl(3). It was also found that the sonication with low density and long duration was more efficient than sonication with high density and short duration at the same energy input for sludge disintegration, and a transmutative power function model can be used to describe the process of ultrasonic disintegration.

Ultrasonic Communication Project, Phase 1, FY1999

Energy Technology Data Exchange (ETDEWEB)

Haynes, H.D.; Akerman, M.A.; Baylor, V.M.

2000-06-01

This Phase 1 project has been successful in identifying, exploring, and demonstrating methods for ultrasonic-based communication with an emphasis on the application of digital signal processing techniques. During the project, at the direction of the agency project monitor, particular attention was directed at sending and receiving ultrasonic data through air and through pipes that would be commonly found in buildings. Efforts were also focused on development of a method for transmitting computer files ultrasonically. New methods were identified and evaluated for ultrasonic communication. These methods are based on a technique called DFS. With DFS, individual alphanumeric characters are broken down into a sequence of bits, and each bit is used to generate a discrete ultrasonic frequency. Characters are then transmitted one-bit-at-a-time, and reconstructed by the receiver. This technique was put into practice through the development of LabVIEW{trademark}VIs. These VIs were integrated with specially developed electronic circuits to provide a system for demonstrating the transmission and reception/reconstruction of typed messages and computer files. Tests were performed to determine the envelope for ultrasound transmission through pipes (with and without water) versus through air. The practical aspects of connections, efficient electronics, impedance matching, and the effect of damping mechanisms were all investigated. These tests resulted in a considerable number of reference charts that illustrate the absorption of ultrasound through different pipe materials, both with and without water, as a function of distance. Ultrasound was found to be least attenuated by copper pipe and most attenuated by PVC pipe. Water in the pipe provides additional damping and attenuation of ultrasonic signals. Dramatic improvements are observed, however, in ultrasound signal strength if the transducers are directly coupled to the water, rather than simply attaching them to the outside of

Ultrasonic Resonance Spectroscopy of Composite Rims for Flywheel Rotors

Science.gov (United States)

Harmon, Laura M.; Baaklini, George Y.

2002-01-01

Flywheel energy storage devices comprising multilayered composite rotor systems are being studied extensively for utilization in the International Space Station. These composite material systems were investigated with a recently developed ultrasonic resonance spectroscopy technique. The ultrasonic system employs a continuous swept-sine waveform and performs a fast Fourier transform (FFT) on the frequency response spectrum. In addition, the system is capable of equalizing the amount of energy at each frequency. Equalization of the frequency spectrum, along with interpretation of the second FFT, aids in the evaluation of the fundamental frequency. The frequency responses from multilayered material samples, with and without known defects, were analyzed to assess the capabilities and limitations of this nondestructive evaluation technique for material characterization and defect detection. Amplitude and frequency changes were studied from ultrasonic responses of thick composite rings and a multiring composite rim. A composite ring varying in thickness was evaluated to investigate the full thickness resonance. The frequency response characteristics from naturally occurring voids in a composite ring were investigated. Ultrasonic responses were compared from regions with and without machined voids in a composite ring and a multiring composite rim. Finally, ultrasonic responses from the multiring composite rim were compared before and after proof spin testing to 63,000 rpm.

Quarantine cold treatments for Ceratitis capitata and Anastrepha fraterculus (Diptera: Tephritidae) for citrus in Argentina: conclusions after 10 years of research

International Nuclear Information System (INIS)

Willink, Eduardo; Gastaminza, Gerardo; Salvatore, Analia; Gramajo, M. Cecilia; Acenolaza, Mariana; Avila, Rosana; Favre, Paola

2006-01-01

Argentina has quarantine restrictions in some markets due to the presence of two quarantine fruit fly pests: Ceratitis capitata and Anastrepha fraterculus. One alternative is the use of cold quarantine treatments during transport of the commodities. Since 1996, the Estacion Experimental Agroindustrial Obispo Colombres (EEAOC), Tucuman, Argentina, has developed different cold quarantine treatments for citrus. In the present work we present all the data the EEAOC generated in the last ten years in order to facilitate the development of such cold treatments. Fruit flies were obtained from the colonies reared at EEAOC. Four citrus species were analyzed: lemon, grapefruit, orange and tangerines. Different varieties were analyzed for each fruit species. Sensitivity trials aiming at determine the most tolerant stage as well as to asses if there is any influence of varieties on cold tolerance were performed. Finally we compared the tolerance to cold between the two species. Sensitivity trials showed that mature larvae (L3) are the most tolerant stage for both fruit fly species. There was no effect of the varieties and the two fruit fly species were equally sensible to cold. Our results provide strong evidence in favor of concluding that any cold treatment developed for C. capitata is effective for A. fraterculus. (author)

Quarantine cold treatments for Ceratitis capitata and Anastrepha fraterculus (Diptera: Tephritidae) for citrus in Argentina: conclusions after 10 years of research

Energy Technology Data Exchange (ETDEWEB)

Willink, Eduardo; Gastaminza, Gerardo; Salvatore, Analia; Gramajo, M. Cecilia; Acenolaza, Mariana; Avila, Rosana; Favre, Paola, E-mail: ewillink@eeaoc.org.a [Estacion Experimental Agroindustrial Obispo Colombres (EEAOC), Tucuman (Argentina)

2006-07-01

Argentina has quarantine restrictions in some markets due to the presence of two quarantine fruit fly pests: Ceratitis capitata and Anastrepha fraterculus. One alternative is the use of cold quarantine treatments during transport of the commodities. Since 1996, the Estacion Experimental Agroindustrial Obispo Colombres (EEAOC), Tucuman, Argentina, has developed different cold quarantine treatments for citrus. In the present work we present all the data the EEAOC generated in the last ten years in order to facilitate the development of such cold treatments. Fruit flies were obtained from the colonies reared at EEAOC. Four citrus species were analyzed: lemon, grapefruit, orange and tangerines. Different varieties were analyzed for each fruit species. Sensitivity trials aiming at determine the most tolerant stage as well as to asses if there is any influence of varieties on cold tolerance were performed. Finally we compared the tolerance to cold between the two species. Sensitivity trials showed that mature larvae (L3) are the most tolerant stage for both fruit fly species. There was no effect of the varieties and the two fruit fly species were equally sensible to cold. Our results provide strong evidence in favor of concluding that any cold treatment developed for C. capitata is effective for A. fraterculus. (author)

Multipath ultrasonic gas flow-meter based on multiple reference waves.

Science.gov (United States)

Zhou, Hongliang; Ji, Tao; Wang, Ruichen; Ge, Xiaocheng; Tang, Xiaoyu; Tang, Shizhen

2018-01-01

Several technologies can be used in ultrasonic gas flow-meters, such as transit-time, Doppler, cross-correlation and etc. In applications, the approach based on measuring transit-time has demonstrated its advantages and become more popular. Among those techniques which can be applied to determine time-of-flight (TOF) of ultrasonic waves, including threshold detection, cross correlation algorithm and other digital signal processing algorithms, cross correlation algorithm has more advantages when the received ultrasonic signal is severely disturbed by the noise. However, the reference wave for cross correlation computation has great influence on the precise measurement of TOF. In the applications of the multipath flow-meters, selection of the reference wave becomes even more complicated. Based on the analysis of the impact factors that will introduce noise and waveform distortion of ultrasonic waves, an averaging method is proposed to determine the reference wave in this paper. In the multipath ultrasonic gas flow-meter, the analysis of each path of ultrasound needs its own reference wave. In case study, a six-path ultrasonic gas flow-meter has been designed and tested with air flow through the pipeline. The results demonstrate that the flow rate accuracy and the repeatability of the TOF are significantly improved by using averaging reference wave, compared with that using random reference wave. Copyright © 2017 Elsevier B.V. All rights reserved.

Ultrasonic superlensing jets and acoustic-fork sheets

Energy Technology Data Exchange (ETDEWEB)

Mitri, F.G., E-mail: F.G.Mitri@ieee.org

2017-05-18

Focusing acoustical (and optical) beams beyond the diffraction limit has remained a major challenge in imaging instruments and systems, until recent advances on “hyper” or “super” lensing and higher-resolution imaging techniques have shown the counterintuitive violation of this rule under certain circumstances. Nonetheless, the proposed technologies of super-resolution acoustical focusing beyond the diffraction barrier require complex tools such as artificially engineered metamaterials, and other hardware equipment that may not be easily synthesized or manufactured. The present contribution therefore suggests a simple and reliable method of using a sound-penetrable circular cylinder lens illuminated by a nonparaxial Gaussian acoustical sheet (i.e. finite beam in 2D) to produce non-evanescent ultrasonic superlensing jets (or bullets) and acoustical ‘snail-fork’ shaped wavefronts with limited diffraction. The generalized (near-field) scattering theory for acoustical sheets of arbitrary wavefronts and incidence is utilized to synthesize the incident beam based upon the angular spectrum decomposition method and the multipole expansion method in cylindrical wave functions to compute the scattered pressure around the cylinder with particular emphasis on its physical properties. The results show that depending on the beam and lens parameters, a tight focusing (with dimensions much smaller than the beam waist) can be achieved. Subwavelength resolution can be also achieved by selecting a lens material with a speed of sound exceeding that of the host fluid medium. The ultrasonic superlensing jets provide the impetus to develop improved subwavelength microscopy and acoustical image-slicing systems, cell lysis and surgery, and photoacoustic imaging to name a few examples. Moreover, an acoustical fork-sheet generation may open innovative avenues in reconfigurable on-chip micro/nanoparticle tweezers and surface acoustic waves devices. - Highlights: • Ultrasonic

Cold urticaria. Dissociation of cold-evoked histamine release and urticara following cold challenge.

Science.gov (United States)

Keahey, T M; Greaves, M W

1980-02-01

Nine patients with acquired cold urticaria were studied to assess the effects of beta-adrenergic agents, xanthines, and corticosteroids on cold-evoked histamine release from skin in vivo. The patients, in all of whom an immediate urticarial response developed after cooling of the forearm, demonstrated release of histamine into the venous blood draining that forearm. Following treatment with aminophylline and albuterol in combination or prednisone alone, suppression of histamine release occurred in all but one patient. In some patients, this was accompanied by a subjective diminution in pruritus or buring, but there was no significant improvement in the ensuing edema or erythema. In one patient, total suppression of histamine release was achieved without any effect on whealing and erythema in response to cold challenge. Our results suggest that histamine is not central to the pathogenesis of vascular changes in acquired cold urticaria.

21 CFR 892.1550 - Ultrasonic pulsed doppler imaging system.

Science.gov (United States)

2010-04-01

... system. (a) Identification. An ultrasonic pulsed doppler imaging system is a device that combines the... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic pulsed doppler imaging system. 892.1550... include signal analysis and display equipment, patient and equipment supports, component parts, and...

A Comparative Analysis of the Rebound Hammer and Ultrasonic ...

African Journals Online (AJOL)

This work presents a study on the comparison between some non-destructive testing tech-niques (Rebound Hammer and Ultrasonic Pulse Velocity). Tests were performed to com-pare the accuracy between the rebound hammer and the ultrasonic pulse velocity methodin estimating the strength of concrete. Eighty samples ...

PROSPECTS FOR APPLICATION OF FLEXIBLE ULTRASONIC WAVEGUIDE SYSTEMS IN MEDICINE AND ENGINEERING

Directory of Open Access Journals (Sweden)

V. T. Minchenya

2010-01-01

Full Text Available The article presents comprehensive review of current and possible future applications of flexible ultrasonic waveguides in medicine and engineering. Issues of design, modelling and manufacturing of flexible waveguides are considered. The article also presents some results of the authors in this field, particularly modelling techniques developed for the design of flexible waveguides and ultrasonic technologies and equipment for ultrasonic thromboectomy, heating of frozen fuel and ultrasonic drilling of brittle materials. Novel technology for manufacturing flexible waveguides based on electrolytic-plasma machining is also described

Nuclear Radiation Tolerance of Single Crystal Aluminum Nitride Ultrasonic Transducer

Science.gov (United States)

Reinhard, Brian; Tittmann, Bernhard R.; Suprock, Andrew

Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models, (Rempe et al., 2011; Kazys et al., 2005). These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2. The irradiation is also supported by a multi-National Laboratory collaboration funded by the Nuclear Energy Enabling Technologies Advanced Sensors and Instrumentation (NEET ASI) program. The results from this irradiation, which started in February 2014, offer the potential to enable the development of novel radiation tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. Hence, results from this irradiation offer the potential to bridge the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the

Ultrasonic analysis of UO{sub 2} pellets

Energy Technology Data Exchange (ETDEWEB)

Bittencourt, Marcelo de S.Q.; Baroni, Douglas B.; Martorelli, Daniel S., E-mail: bittenc@ien.gov.br, E-mail: douglasbaroni@ien.gov.br, E-mail: daniel@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Ultrassom; Dias, Fabio C.; Silva, Jose W.S. da, E-mail: fabio@ird.gov.br, E-mail: wanderley@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Salvaguardas

2013-07-01

Ceramic materials have been widely used for various purposes in many different industries due to certain characteristics, such as high melting point and high resistance to corrosion. In the nuclear area, ceramics are of great importance due to the process of fabrication of fuel pellets for nuclear reactors. Generally, high accuracy destructive techniques are used to characterize nuclear materials for fuel fabrication. These techniques usually require costly equipment and facilities, as well as experienced personnel. This paper aims at presenting an analysis methodology for UO2 pellets using a non-destructive ultrasonic technique for porosity measurement. This technique differs from traditional ultrasonic techniques in the sense it uses ultrasonic pulses in frequency domain instead of time domain. Therefore, specific characteristics of the analyzed material are associated with the obtained frequency spectrum. In the present work, four fuel grade UO2 pellets were analyzed and the corresponding results evaluated. (author)

Effect of ultrasonic pretreatment on purified water disinfection

International Nuclear Information System (INIS)

Simon Andreu, P.; Lardin Mifsut, C.; Vergara Romero, L.; Polo Canas, P. M.; Perez Sanchez, P.; Rancano Perez, A.

2009-01-01

Due to the importance of a suitable water disinfection in order to insure a pollutant effect minimization against environment, this work has been carried out to determine how can affect an ultrasonic pre-treatment upon disinfection step. It has been confirmed the ultrasonic disintegration of bacterial cells in treated water and disinfectant power of treatment by itself, which is not enough to be used as a single method in water disinfection. It has also been proved that from a technical and economical point of view the combination of UV and ultrasound improves the UV treatment performance. Finally, it has been detected that an ultrasonic pre-treatment increases chlorination effectiveness, however the high cost in this combination makes it unfeasible of industrial scale. (Author) 6 refs

Measurement of transitional flow in pipes using ultrasonic flowmeters

Energy Technology Data Exchange (ETDEWEB)

Zheng-Gang, Liu; Guang-Sheng, Du; Zhu-Feng, Shao; Qian-Ran, He; Chun-Li, Zhou, E-mail: lzhenggang@sdu.edu.cn [School of Energy and Power Engineering, Qian-Fo-shan campus, Shandong University, Jinan City 250061, Shandong Province (China)

2014-10-01

The accuracy of an ultrasonic flowmeter depends on the ratio k of average profile velocity of pipe and average velocity of an ultrasonic propagation path. But there is no appropriate method of calculating k for transition flow. In this paper, the velocity field of the transition flow in a pipe is measured by particle image velocimetry. On this basis, the k of U-shaped and V-shaped ultrasonic flowmeter is obtained when Reynolds number is between 2000 and 20 000. It is shown that the k is constant when the Reynolds number is in the range of 2000–2400 and 5400–20 000, and the k decreases with the increasing of Re when the Reynolds number is 2400–5400. The results of study can be used to improve the measurement accuracy of ultrasonic flowmeters when flow is transition flow and can provide help for the study of pipe flow. (paper)

Prediction of strength of wood composite materials using ultrasonic

International Nuclear Information System (INIS)

Mahmoud, M.K.; Emam, A.

2005-01-01

Wood is a biological material integrating a very large variability of its mechanical properties (tensile and compressive), on the two directional longitudinal and transverse Ultrasonic method has been utilized to measure both wood physical and / or wood mechanical properties. The aim of this article is to show the development of ultrasonic technique for quality evaluation of trees, wood material and wood based composites. For quality assessment of these products we discuss the nondestructive evaluation of different factors such as: moisture content, temperature, biological degradation induced by bacterial attack and fungal attack. These techniques were adapted for trees, timber and wood based composites. The present study discusses the prediction of tensile and compressive strength of wood composite materials using ultrasonic testing. Empirical relationships between the tensile properties, compression strength and ultrasonic were proposed. The experimental results indicate the possibility of establishing a relationship between tensile strength and compression values. Moreover, the fractures in tensile and compressive are discussed by photographic

Natural cold baryogenesis from strongly interacting electroweak symmetry breaking

International Nuclear Information System (INIS)

Konstandin, Thomas; Servant, Géraldine

2011-01-01

The mechanism of ''cold electroweak baryogenesis'' has been so far unpopular because its proposal has relied on the ad-hoc assumption of a period of hybrid inflation at the electroweak scale with the Higgs acting as the waterfall field. We argue here that cold baryogenesis can be naturally realized without the need to introduce any slow-roll potential. Our point is that composite Higgs models where electroweak symmetry breaking arises via a strongly first-order phase transition provide a well-motivated framework for cold baryogenesis. In this case, reheating proceeds by bubble collisions and we argue that this can induce changes in Chern-Simons number, which in the presence of new sources of CP violation commonly lead to baryogenesis. We illustrate this mechanism using as a source of CP violation an effective dimension-six operator which is free from EDM constraints, another advantage of cold baryogenesis compared to the standard theory of electroweak baryogenesis. Our results are general as they do not rely on any particular UV completion but only on a stage of supercooling ended by a first-order phase transition in the evolution of the universe, which can be natural if there is nearly conformal dynamics at the TeV scale. Besides, baryon-number violation originates from the Standard Model only

Comparison radiographic and automated ultrasonic inspection of pipeline tie-in welds

International Nuclear Information System (INIS)

Connelly, T.; Gross, B.

2007-01-01

In recent years the use of automated ultrasonic inspection (AUT) for pipeline girth welds has seen rapid growth and is now used almost exclusively for all gas metal arc welding (GMAW) girth weld inspection. The following paper reviews some of the major features of ultrasonic inspection by comparison to conventional Film Radiography (RT) and reviews the use of ultrasonic inspection for pipeline and tie-in welds. (author)

Measurement of hydroxyl radical production in ultrasonic aqueous solutions by a novel chemiluminescence method.

Science.gov (United States)

Hu, Yufei; Zhang, Zhujun; Yang, Chunyan

2008-07-01

Measurement methods for ultrasonic fields are important for reasons of safety. The investigation of an ultrasonic field can be performed by detecting the yield of hydroxyl radicals resulting from ultrasonic cavitations. In this paper, a novel method is introduced for detecting hydroxyl radicals by a chemiluminescence (CL) reaction of luminol-hydrogen peroxide (H2O2)-K5[Cu(HIO6)2](DPC). The yield of hydroxyl radicals is calculated directly by the relative CL intensity according to the corresponding concentration of H2O2. This proposed CL method makes it possible to perform an in-line and real-time assay of hydroxyl radicals in an ultrasonic aqueous solution. With flow injection (FI) technology, this novel CL reaction is sensitive enough to detect ultra trace amounts of H2O2 with a limit of detection (3sigma) of 4.1 x 10(-11) mol L(-1). The influences of ultrasonic output power and ultrasonic treatment time on the yield of hydroxyl radicals by an ultrasound generator were also studied. The results indicate that the amount of hydroxyl radicals increases with the increase of ultrasonic output power (< or = 15 W mL(-1)). There is a linear relationship between the time of ultrasonic treatment and the yield of H2O2. The ultrasonic field of an ultrasonic cleaning baths has been measured by calculating the yield of hydroxyl radicals.

Ultrasonic spectroscopy applications in condensed matter physics and materials science

CERN Document Server

Leisure, Robert G

2017-01-01

Ultrasonic spectroscopy is a technique widely used in solid-state physics, materials science, and geology that utilizes acoustic waves to determine fundamental physical properties of materials, such as their elasticity and mechanical energy dissipation. This book provides complete coverage of the main issues relevant to the design, analysis, and interpretation of ultrasonic experiments. Topics including elasticity, acoustic waves in solids, ultrasonic loss, and the relation of elastic constants to thermodynamic potentials are covered in depth. Modern techniques and experimental methods including resonant ultrasound spectroscopy, digital pulse-echo, and picosecond ultrasound are also introduced and reviewed. This self-contained book includes extensive background theory and is accessible to students new to the field of ultrasonic spectroscopy, as well as to graduate students and researchers in physics, engineering, materials science, and geophysics.

Mechanisms and kinetics models for ultrasonic waste activated sludge disintegration.

Science.gov (United States)

Wang, Fen; Wang, Yong; Ji, Min

2005-08-31

Ultrasonic energy can be applied as pre-treatment to disintegrate sludge flocs and disrupt bacterial cells' walls, and the hydrolysis can be improved, so that the rate of sludge digestion and methane production is improved. In this paper, by adding NaHCO3 to mask the oxidizing effect of OH, the mechanisms of disintegration are investigated. In addition, kinetics models for ultrasonic sludge disintegration are established by applying multi-variable linear regression method. It has been found that hydro-mechanical shear forces predominantly responsible for the disintegration, and the contribution of oxidizing effect of OH increases with the amount of the ultrasonic density and ultrasonic intensity. It has also been inferred from the kinetics model which dependent variable is SCOD+ that both sludge pH and sludge concentration significantly affect the disintegration.

Ultrasonic methods in solid state physics

CERN Document Server

Truell, John; Elbaum, Charles

1969-01-01

Ultrasonic Methods in Solid State Physics is devoted to studies of energy loss and velocity of ultrasonic waves which have a bearing on present-day problems in solid-state physics. The discussion is particularly concerned with the type of investigation that can be carried out in the megacycle range of frequencies from a few megacycles to kilomegacycles; it deals almost entirely with short-duration pulse methods rather than with standing-wave methods. The book opens with a chapter on a classical treatment of wave propagation in solids. This is followed by separate chapters on methods and techni

Ultrasonic two-dimensional imaging of the heart with multiscan

International Nuclear Information System (INIS)

Roelandt, J.R.T.C.

1980-01-01

The aim of the author was to present the implementation into cardiology of the ultrasonic linear array scanner. The first clinical results, the progress in examination technique and potential applications are described. One method which complements the ultrasonic imaging capabilities is the use of the echo contrast. (Auth.)

Ultrasonic defect detection method for socket welding joint

International Nuclear Information System (INIS)

Tominaga, Masaaki; Matsuo, Toshiyuki; Ueno, Akihiro; Watanabe, Kunimichi; Kawamata, Kunio.

1995-01-01

The present invention provides a method of detecting defects over a wide range of a socket weld portion of various kinds of pipelines used, for example, in a nuclear power plant. Namely, an inclined probe is disposed to a jig for detecting defects by ultrasonic waves. This is rotated at least by one turn along the peripheral surface of the material to be detected such as weld tube joints. Defects of weld portion of the material can be detected automatically by using ultrasonic waves during the rotation. The inclined probe for detecting defects by ultrasonic waves comprises a transmission portion having a planar transmittance oscillator disposed to a wedge on the transmission side and a receiving portion comprising a planar receiving oscillator disposed to a wedge on the receiving side. With such a constitution, ultrasonic waves are emitted from the transmission portion to the defect detection portion in the welded portion. If a defect is present, defective echo is reflected to the receiving portion disposed ahead of the probe. Since the defective echo changes depending on the height of the detective portion, the estimation of the height of the defect can be facilitated. (I.S.)

Cold H I clouds near the supernova remnant W44

International Nuclear Information System (INIS)

Sato, F.

1986-01-01

The cold H I clouds near the supernova remnant W44 are investigated by the use of the Maryland-Green Bank Survey (Westerhout 1973). Several clouds with a mean diameter of about 20 pc are distributed in the region. They do not seem to make a shell around W44, contrary to the suggestion by Knapp and Kerr (1974) based on the low-resolution data at coarse grids. Some of them form a chain, about 100 pc in length, extending approximately along the galactic equator. It resembles the cold H I cloud near W3 and W4. The major constituent of the clouds is probably the hydrogen molecule, and the total mass of the entire complex amounts to 25,000 81,000 solar masses. The estimated Jeans mass indicates that they will contract to dense molecular clouds. Therefore, it may safely be concluded that the cold H1 cloud complex near W44 is a giant molecular cloud at an early evolutionary stage. 14 references

Phased Array Ultrasonic Evaluation of Space Shuttle Main Engine (SSME) Nozzle Weld

Science.gov (United States)

James, Steve; Engel, J.; Kimbrough, D.; Suits, M.; Hopson, George (Technical Monitor)

2001-01-01

This viewgraph presentation gives an overview of the phased array ultrasonic evaluation of the Space Shuttle Main Engine (SSME) nozzle weld. Details are given on the nondestructive testing evaluation approach, conventional shear wave and phased array techniques, and an x-ray versus phased array risk analysis. The field set-up was duplicated to the greatest extent possible in the laboratory and the phased array ultrasonic technique was developed and validated prior to weld evaluation. Results are shown for the phased array ultrasonic evaluation and conventional ultrasonic evaluation results.

A study on the ultrasonic measurement for damage evaluation of power plant bearing

International Nuclear Information System (INIS)

Lee, Sang Guk

2004-01-01

For the purpose of monitoring by ultrasonic test of the ball bearing conditions in rotating machinery, a system for their diagnosis was developed. Ultrasonic technique is used to detect abnormal conditions in the bearing system. And various data such as frequency spectrum, energy and amplitude of ultrasonic signals, and ultrasonic parameters were acquired during experiments with the simulated ball bearing system. Based on the above results and practical application for power plant, algorithms and judgement criteria for diagnosis system was established. Bearing diagnosis system is composed of four parts as follows : sensing part for ultrasonic sensor and preamplifier, signal processing part for measuring frequency spectrum, energy and amplitude, interface part for connecting ultrasonic signal to PC using A/D converter, graphic display and software part for display of bearing condition and for managing of diagnosis program

Relationships of self-identified cold tolerance and cold-induced vasodilatation in the finger

Science.gov (United States)

Park, Joonhee; Lee, Joo-Young

2016-04-01

This study was conducted to investigate relationships of self-identified cold tolerance and cold-induced vasodilatation (CIVD) in the finger. Nine males and 34 females participated in the following 2 tests: a CIVD test and a self-reported survey. The CIVD test was conducted 30-min cold-water immersion (3.8 ± 0.3 °C) of the middle finger at an air temperature of 27.9 ± 0.1 °C. The self-reported questionnaire consisted of 28 questions about whole and local body cold and heat tolerances. By a cluster analysis on the survey results, the participants were divided into two groups: high self-identified cold tolerance (HSCT, n = 25) and low self-identified cold tolerance (LSCT, n = 18). LSCT had lower self-identified cold tolerance ( P cold or heat tolerance had relationships with cold tolerance index, T max, and amplitude ( P cold tolerance classified through a standardized survey could be a good index to predict physiological cold tolerance.

Finite Element Simulation of the Shear Effect of Ultrasonic on Heat Exchanger Descaling

Science.gov (United States)

Lu, Shaolv; Wang, Zhihua; Wang, Hehui

2018-03-01

The shear effect on the interface of metal plate and its attached scale is an important mechanism of ultrasonic descaling, which is caused by the different propagation speed of ultrasonic wave in two different mediums. The propagating of ultrasonic wave on the shell is simulated based on the ANSYS/LS-DYNA explicit dynamic analysis. The distribution of shear stress in different paths under ultrasonic vibration is obtained through the finite element analysis and it reveals the main descaling mechanism of shear effect. The simulation result is helpful and enlightening to the reasonable design and the application of the ultrasonic scaling technology on heat exchanger.

Technique for ultrasonic testing of austenitic steel weldments of NPP components

International Nuclear Information System (INIS)

Lantukh, V.M.; Grebennik, V.S.; Kordinov, E.V.; Kesler, N.A.; Shchedrin, I.F.

1987-01-01

Special literature on ultrasonic testing of weldments of austenitic steel is analysed. Technique for ultrasonic testing of the ring and longitudinal butt welded joints of NPP components without reinforcing bead removal is described. Special converter design and fabrication practice are described. Results of experimental check of the developed testing technology and its application during NNPs' mounting and operation are presented. Results of ultrasonic and X-ray testing are compared

Automated electronic intruder simulator for evaluation of ultrasonic intrusion detectors

International Nuclear Information System (INIS)

1979-01-01

An automated electronic intruder simulator for testing ultrasonic intrusion detectors is described. This simulator is primarily intended for use in environmental chambers to determine the effects of temperature and humidity on the operation of ultrasonic intrusion detectors

High performance ultrasonic field simulation on complex geometries

Science.gov (United States)

Chouh, H.; Rougeron, G.; Chatillon, S.; Iehl, J. C.; Farrugia, J. P.; Ostromoukhov, V.

2016-02-01

Ultrasonic field simulation is a key ingredient for the design of new testing methods as well as a crucial step for NDT inspection simulation. As presented in a previous paper [1], CEA-LIST has worked on the acceleration of these simulations focusing on simple geometries (planar interfaces, isotropic materials). In this context, significant accelerations were achieved on multicore processors and GPUs (Graphics Processing Units), bringing the execution time of realistic computations in the 0.1 s range. In this paper, we present recent works that aim at similar performances on a wider range of configurations. We adapted the physical model used by the CIVA platform to design and implement a new algorithm providing a fast ultrasonic field simulation that yields nearly interactive results for complex cases. The improvements over the CIVA pencil-tracing method include adaptive strategies for pencil subdivisions to achieve a good refinement of the sensor geometry while keeping a reasonable number of ray-tracing operations. Also, interpolation of the times of flight was used to avoid time consuming computations in the impulse response reconstruction stage. To achieve the best performance, our algorithm runs on multi-core superscalar CPUs and uses high performance specialized libraries such as Intel Embree for ray-tracing, Intel MKL for signal processing and Intel TBB for parallelization. We validated the simulation results by comparing them to the ones produced by CIVA on identical test configurations including mono-element and multiple-element transducers, homogeneous, meshed 3D CAD specimens, isotropic and anisotropic materials and wave paths that can involve several interactions with interfaces. We show performance results on complete simulations that achieve computation times in the 1s range.

21 CFR 892.1560 - Ultrasonic pulsed echo imaging system.

Science.gov (United States)

2010-04-01

... system. (a) Identification. An ultrasonic pulsed echo imaging system is a device intended to project a... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic pulsed echo imaging system. 892.1560... receiver. This generic type of device may include signal analysis and display equipment, patient and...

Effect of ultrasonic specific energy on waste activated sludge ...

African Journals Online (AJOL)

The effect of ultrasonic specific energy on waste activated sludge (WAS) solubilization and enzyme activity was investigated in this study. Experimental results showed that the increase of ultrasonic specific energy in the range of 0 - 90000 kJ/kg dried sludge (DS) benefited WAS particle size reduction and the solubilization ...

Ultrasonic Technology in Duress Alarms.

Science.gov (United States)

Lee, Martha A.

2000-01-01

Provides the pros and cons of the most commonly used technologies in personal duress alarm systems in the school environment. Discussed are radio frequency devices, infrared systems, and ultrasonic technology. (GR)

Indoor Airborne Ultrasonic Wireless Communication Using OFDM Methods.

Science.gov (United States)

Jiang, Wentao; Wright, William M D

2017-09-01

Concerns still exist over the safety of prolonged exposure to radio frequency (RF) wireless transmissions and there are also potential data security issues due to remote signal interception techniques such as Bluesniping. Airborne ultrasound may be used as an alternative to RF for indoor wireless communication systems for securely transmitting data over short ranges, as signals are difficult to intercept from outside the room. Two types of air-coupled capacitive ultrasonic transducer were used in the implementation of an indoor airborne wireless communication system. One was a commercially available SensComp series 600 ultrasonic transducer with a nominal frequency of 50 kHz, and the other was a prototype transducer with a high- k dielectric layer operating at higher frequencies from 200 to 400 kHz. Binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), and quadrature amplitude modulation (QAM)-based orthogonal frequency division multiplexing modulation methods were successfully implemented using multiple orthogonal subchannels. The modulated ultrasonic signal packets were synchronized using a wireless link, and a least-squares channel estimation algorithm was used to compensate the phase and amplitude distortion introduced by the air channel. By sending and receiving the ultrasonic signals using the SensComp transducers, the achieved maximum system data rate was up to 180 kb/s using 16-QAM with ultrasonic channels from 55 to 99 kHz, over a line-of-sight transmission distance of 6 m with no detectable errors. The transmission range could be extended to 9 and 11 m using QPSK and BPSK modulation schemes, respectively. The achieved data rates for the QPSK and BPSK schemes were 90 and 45 kb/s using the same bandwidth. For the high- k ultrasonic transducers, a maximum data rate up to 800 kb/s with no measurable errors was achieved up to a range of 0.7 m. The attainable transmission ranges were increased to 1.1 and 1.2 m with data rates of 400 and 200 kb

Design and Manufacture an Ultrasonic Dispersion System with Automatic Frequency Adjusting Property

Directory of Open Access Journals (Sweden)

Herlina ABDUL RAHIM

2011-03-01

Full Text Available This paper a novel ultrasonic dispersion system for the cleaning application or dispersing of particles which are mixed in liquid has been proposed. The frequency band of designed system is 30 kHz so that the frequency of ultrasonic wave sweeps from 30 kHz to 60 kHz with 100 Hz steps. One of the superiority of manufactured system in compare with the other similar systems which are available in markets is that this system can transfer the maximum and optimum energy of ultrasonic wave inside the liquid tank with the high efficiency in the whole of the usage time of the system. The used ultrasonic transducers in this system as the generator of ultrasonic wave is the type of air coupled ceramic ultrasonic piezoelectric with the nominal maximum power 50 Watt. The frequency characteristic of applied piezoelectric is that it produces the maximum amplitude of ultrasonic wave on the resonance frequency, so this system is designed to work on resonance frequency of piezoelectric, continuously. This is done by the use of control system which is consisted of two major parts, sensing part and controlling part. The manufactured ultrasonic dispersion system is consisted of 9 piezoelectrics so that it can produce 450 watt ultrasonic energy, totally. The main purpose of this project is to produce a safety system especially for fatigue car driver so as to prevent from accidents. The statistic on road fatality shows that human error constitute of 64.84 % road accidents fatality and 17.4 % due to technical factors. These systems encompassed the approach of hand pressure applied on the steering wheel. The steering will be installed with pressure sensors. At the same time these sensors can be used to measure gripping force while driving.

Rapid formation of nanocrystalline HfO2 powders from amorphous hafnium hydroxide under ultrasonically assisted hydrothermal treatment

International Nuclear Information System (INIS)

Meskin, Pavel E.; Sharikov, Felix Yu.; Ivanov, Vladimir K.; Churagulov, Bulat R.; Tretyakov, Yury D.

2007-01-01

Peculiarities of hafnium hydroxide hydrothermal decomposition were studied by in situ heat flux calorimetry for the first time. It was shown that this process occurs in one exothermal stage (ΔH = -17.95 kJ mol -1 ) at 180-250 deg. C resulting in complete crystallization of amorphous phase with formation of pure monoclinic HfO 2 . It was found that the rate of m-HfO 2 formation can be significantly increased by combining hydrothermal treatment with simultaneous ultrasonic activation

Ultrasonic assessment of additive manufactured Ti-6Al-4V

Science.gov (United States)

Schehl, Norman; Kramb, Vicki; Dierken, Josiah; Aldrin, John; Schwalbach, Edwin; John, Reji

2018-04-01

Additive Manufacturing (AM) processes offer the potential for manufacturing cost savings and rapid insertion into service through production of near net shape components for complicated structures. Use of these parts in high reliability applications such as those in the aerospace industry will require nondestructive characterization methods to ensure post-process material quality in as-built condition. Ultrasonic methods can be used for this quality verification. Depending on the application, the service life of AM components can be sensitive to the part surface condition. The surface roughness and layered structure inherent to the electron-beam powder-bed fusion process necessitates new approaches to evaluate subsurface material integrity in its presence. Experimental methods and data analytics may improve the evaluation of as-built additively manufactured materials. This paper discusses the assessment of additively manufactured EBM Ti-6Al-4V panels using ultrasonic methods and the data analytics applied to evaluate material integrity. The assessment was done as an exploratory study as the discontinuities of interest in these test samples were not known when the measurements were performed. Water immersion ultrasonic techniques, including pulse-echo and through transmission with 10 MHz focused transducers, were used to explore the material integrity of as-built plates. Subsequent destructive mechanical tests of specimens extracted from the plates provided fracture locations indicating critical flaws. To further understand the effect of surface-roughness, an evaluation of ultrasonic response in the presence of as-built surfaces and with the surface removed was performed. The assessment of additive manufactured EBM Ti-6Al-4V panels with ultrasonic techniques indicated that ultrasonic energy was attenuated by the as-built surface roughness. In addition, feature detection was shown to be sensitive to experimental ultrasonic parameters and flaw morphology.

A circular aperture array for ultrasonic tomography and quantitative NDE

Energy Technology Data Exchange (ETDEWEB)

Nielsen, S A

1998-08-01

The main topics of this thesis are ultrasonic tomography and ultrasonic determination of elastic stiffness constants. Both issues are based on a synthetic array with transducer elements distributed uniformly along a circular aperture, i.e., a circular aperture array. The issues are treated both theoretically and experimentally by broadband pulse techniques. Ultrasonic tomography, UCT, from a circular aperture is a relatively new imaging technique in Non-destructive Evaluation (NDE) to acquire cross sectional images in bulk materials. A filtered back-projection algorithm is used to reconstruct images in four different experiments and results of attenuation, velocity and reflection tomograms in Plexiglas of AlSi-alloy cylinders are presented. Two kinds of ultrasonic tomography are introduced: bistatic and monostatic imaging. Both techniques are verified experimentally by Plexiglas cylinders. Different reconstruction artifacts are discussed and theoretical resolution constraints are discussed for various configurations of the circular aperture array. The monostatic technique is used in volumetric imaging. In the experimental verification artificial and real discontinuities in a cylindrical AlSi-alloy are compared with similar discontinuities in a Plexiglas specimen. Finally, some limitations to UCT are discussed. The circular aperture array is used to determine five independent elastic stiffness constants of a unidirectional glass/PET (Poly Ethylene Teraphtalate) laminate. Energy flux propagation and attenuation of ultrasonic waves are considered and velocity surfaces are calculated for different planes of interest. Relations between elastic stiffness constants and engineering constants (i.e., Young`s moduli, shear moduli and Poisson`s ratios) are discussed for an orthotropic composite. Six micromechanical theories are reviewed, and expressions predicting the elastic engineering constants are evaluated. The micromechanical predicted elastic stiffness constants for the

Laser-Ultrasonic Testing and its Applications to Nuclear Reactor Internals

Science.gov (United States)

Ochiai, M.; Miura, T.; Yamamoto, S.

2008-02-01

A new nondestructive testing technique for surface-breaking microcracks in nuclear reactor components based on laser-ultrasonics is developed. Surface acoustic wave generated by Q-switched Nd:YAG laser and detected by frequency-stabilized long pulse laser coupled with confocal Fabry-Perot interferometer is used to detect and size the cracks. A frequency-domain signal processing is developed to realize accurate sizing capability. The laser-ultrasonic testing allows the detection of surface-breaking microcrack having a depth of less than 0.1 mm, and the measurement of their depth with an accuracy of 0.2 mm when the depth exceeds 0.5 mm including stress corrosion cracking. The laser-ultrasonic testing system combined with laser peening system, which is another laser-based maintenance technology to improve surface stress, for inner surface of small diameter tube is developed. The generation laser in the laser-ultrasonic testing system can be identical to the laser source of the laser peening. As an example operation of the system, the system firstly works as the laser-ultrasonic testing mode and tests the inner surface of the tube. If no cracks are detected, the system then changes its work mode to the laser peening and improves surface stress to prevent crack initiation. The first nuclear industrial application of the laser-ultrasonic testing system combined with the laser peening was completed in Japanese nuclear power plant in December 2004.

Comet assay as a cold chain control tool

International Nuclear Information System (INIS)

Duarte, Renato Cesar

2009-01-01

Bearing in mind an ever more demanding market regarding the quality of food, it has been necessary to develop processes that meet the demands of consumers. Within the existing processes the cold chain and irradiation stand out. The cold chain comprises all the stages of conserving food from production, cooling, freezing, storing and transportation to the final consumer. Irradiation, as a means of conserving food, prolongs the shelf life, inhibits budding and reduces pathogenic contamination among other benefits. Is very important the identification of food degradation in function of failure on the processes which they were subjected. The comet assay is a screening test widely studied, considerate fast and with low cost. By the fact of the test identify breaks on the DNA, may be possible use the comet test on the control of cold chain failures that degrade de food. The labels and stamp, do not consider the previous food situation and indicate failures from the moment where they be placed in contact with the product. With the comet assay is possible to check the degradation that has occurred in liver chicken samples until the moment of comet's test realization. (author)

Ultrasonic propagation velocity in magnetic and magnetorheological fluids due to an external magnetic field

International Nuclear Information System (INIS)

Bramantya, M A; Sawada, T; Motozawa, M

2010-01-01

Ultrasonic propagation velocity in a magnetic fluid (MF) and magnetorheological fluid (MRF) changes with the application of an external magnetic field. The formation of clustering structures inside the MF and MRF clearly has an influence on the ultrasonic propagation velocity. Therefore, we propose a qualitative analysis of these structures by measuring properties of ultrasonic propagation. Since MF and MRF are opaque, non-contact inspection using the ultrasonic technique can be very useful for analyzing the inner structures of MF and MRF. In this study, we measured ultrasonic propagation velocity in a hydrocarbon-based MF and MRF precisely. Based on these results, the clustering structures of these fluids are analyzed experimentally in terms of elapsed time dependence and the effect of external magnetic field strength. The results reveal hysteresis and anisotropy in the ultrasonic propagation velocity. We also discuss differences of ultrasonic propagation velocity between MF and MRF.

Electrocautery causes more ischemic peritoneal tissue damage than ultrasonic dissection.

NARCIS (Netherlands)

Broek, R.P.G ten; Wilbers, J.; Goor, H. van

2011-01-01

BACKGROUND: Minimizing peritoneal tissue injury during abdominal surgery has the benefit of reducing postoperative inflammatory response, pain, and adhesion formation. Ultrasonic dissection seems to reduce tissue damage. This study aimed to compare electrocautery and ultrasonic dissection in terms

Correlation between ultrasonic nonlinearity and elastic nonlinearity in heat-treated aluminum alloy

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Beom; Jhang, Kyung Young [Hanyang University, Seoul (Korea, Republic of)

2017-04-15

The nonlinear ultrasonic technique is a potential nondestructive method to evaluate material degradation, in which the ultrasonic nonlinearity parameter is usually measured. The ultrasonic nonlinearity parameter is defined by the elastic nonlinearity coefficients of the nonlinear Hooke’s equation. Therefore, even though the ultrasonic nonlinearity parameter is not equal to the elastic nonlinearity parameter, they have a close relationship. However, there has been no experimental verification of the relationship between the ultrasonic and elastic nonlinearity parameters. In this study, the relationship is experimentally verified for a heat-treated aluminum alloy. Specimens of the aluminum alloy were heat-treated at 300°C for different periods of time (0, 1, 2, 5, 10, 20, and 50 h). The relative ultrasonic nonlinearity parameter of each specimen was then measured, and the elastic nonlinearity parameter was determined by fitting the stress-strain curve obtained from a tensile test to the 5th-order-polynomial nonlinear Hooke’s equation. The results showed that the variations in these parameters were in good agreement with each other.

Application of nonlinear ultrasonic method for monitoring of stress state in concrete

International Nuclear Information System (INIS)

Kim, Gyu Jin; Kwak, Hyo Gyoung; Park, Sun Jong

2016-01-01

As the lifespan of concrete structures increases, their load carrying capacity decreases owing to cyclic loads and long-term effects such as creep and shrinkage. For these reasons, there is a necessity for stress state monitoring of concrete members. Particularly, it is necessary to evaluate the concrete structures for behavioral changes by using a technique that can overcome the measuring limitations of usual ultrasonic nondestructive evaluation methods. This paper proposes the use of a nonlinear ultrasonic method, namely, nonlinear resonant ultrasonic spectroscopy (NRUS) for the measurement of nonlinearity parameters for stress monitoring. An experiment compared the use of NRUS method and a linear ultrasonic method, namely, ultrasonic pulse velocity (UPV) to study the effects of continuously increasing loads and cyclic loads on the nonlinearity parameter. Both NRUS and UPV methods found a similar direct relationship between load level and that parameter. The NRUS method showed a higher sensitivity to micro-structural changes of concrete than UPV method. Thus, the experiment confirms the possibility of using the nonlinear ultrasonic method for stress state monitoring of concrete members

Application of nonlinear ultrasonic method for monitoring of stress state in concrete

Energy Technology Data Exchange (ETDEWEB)

Kim, Gyu Jin; Kwak, Hyo Gyoung [Dept. of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Park, Sun Jong [Dept. of Structural System and Site Safety Evaluation, Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2016-04-15

As the lifespan of concrete structures increases, their load carrying capacity decreases owing to cyclic loads and long-term effects such as creep and shrinkage. For these reasons, there is a necessity for stress state monitoring of concrete members. Particularly, it is necessary to evaluate the concrete structures for behavioral changes by using a technique that can overcome the measuring limitations of usual ultrasonic nondestructive evaluation methods. This paper proposes the use of a nonlinear ultrasonic method, namely, nonlinear resonant ultrasonic spectroscopy (NRUS) for the measurement of nonlinearity parameters for stress monitoring. An experiment compared the use of NRUS method and a linear ultrasonic method, namely, ultrasonic pulse velocity (UPV) to study the effects of continuously increasing loads and cyclic loads on the nonlinearity parameter. Both NRUS and UPV methods found a similar direct relationship between load level and that parameter. The NRUS method showed a higher sensitivity to micro-structural changes of concrete than UPV method. Thus, the experiment confirms the possibility of using the nonlinear ultrasonic method for stress state monitoring of concrete members.

Dynamic Takagi-Sugeno Model for the Control of Ultrasonic Motor

Directory of Open Access Journals (Sweden)

Shi Jingzhuo

2011-01-01

Full Text Available Model of ultrasonic motor is the foundation of the design of ultrasonic motor's speed and position controller. A two-input and one-output dynamic Takagi-Sugeno model of ultrasonic motor driving system is worked out using fuzzy reasoning modeling method in this paper. Many fuzzy reasoning modeling methods are sensitive to the initial values and easy to fall into local minimum, and have a large amount of calculation. In order to overcome these defects, equalized universe method is used in this paper to get clusters centers and obtain fuzzy clustering membership functions, and then, the unknown parameters of the conclusions of fuzzy rules are identified using least-square method. Different experimental data that are tested with different operational conditions are used to examine the validity of the fuzzy model. Comparison between experimental data and calculated data of the model indicates that the model can well describe the nonlinear characteristics among the frequency, amplitude of driving voltage and rotating speed. The proposed fuzzy model can be used to analyze the performance of ultrasonic motor driving system, and also can be used to design the speed and position controller of ultrasonic motor.

Mode Identification of Guided Ultrasonic Wave using Time- Frequency Algorithm

International Nuclear Information System (INIS)

Yoon, Byung Sik; Yang, Seung Han; Cho, Yong Sang; Kim, Yong Sik; Lee, Hee Jong

2007-01-01

The ultrasonic guided waves are waves whose propagation characteristics depend on structural thickness and shape such as those in plates, tubes, rods, and embedded layers. If the angle of incidence or the frequency of sound is adjusted properly, the reflected and refracted energy within the structure will constructively interfere, thereby launching the guided wave. Because these waves penetrate the entire thickness of the tube and propagate parallel to the surface, a large portion of the material can be examined from a single transducer location. The guided ultrasonic wave has various merits like above. But various kind of modes are propagating through the entire thickness, so we don't know the which mode is received. Most of applications are limited from mode selection and mode identification. So the mode identification is very important process for guided ultrasonic inspection application. In this study, various time-frequency analysis methodologies are developed and compared for mode identification tool of guided ultrasonic signal. For this study, a high power tone-burst ultrasonic system set up for the generation and receive of guided waves. And artificial notches were fabricated on the Aluminum plate for the experiment on the mode identification

STADUS - Ultrasonic data acquisition and processing system

International Nuclear Information System (INIS)

Saglio, Robert; Birac, A.M.; Frappier, J.C.

1982-05-01

The CEA (Commissariat a l'Energie Atomique) has developed a system for the acquisition and analysis of data recorded during ultrasonic testing. Initially this system was designed and built for the needs of in-service inspection of PWR type power reactors. It is in far wider use today for miscellaneous automatic ultrasonic inspection procedures. This system records, in digital form, the ultrasonic data supplied by the transducers (maximum 16 simultaneous channels), and the geometric coordinates defining the position of the inspection tool. Based on these data, which are recorded on floppy disk, this system helps to display data in the form of A SCAN, B SCAN and C SCAN images. In addition, processing programs of data transfer from the STADUS floppy disks have been developed and inserted on computers more powerful than the one used in the STADUS system. These programs serve to obtain different fault charts on an adjustable scale, as well as listings concerning the defect positions and dimensions [fr

Wound healing in the jugal mucosa of rats with a cold blade scalpel and an ultrasonic harmonic scalpel.

Science.gov (United States)

De Masi, Elen Carolina David João; Rocha, Sergio Luis; Mocellin, Marcos; Faria, João Luis Garcia de

2009-01-01

Ultrasound harmonic scalpel has been recently introduced in otorhinolaryngological procedures. to assess macro and microscopic evolution of the healing process of wounds created in the jugal mucosa of rats by the use of ultrasound scalpel. we used 30 Wistar rats in which we made mucosal incisions on the right jugal mucosa with the ultrasound harmonic scalpel (USHS) and on the left side with the cold blade scalpel (CBS). Macroscopic and microscopic evaluations were carried out on the third, seventh and fourteenth days of postoperative. For the microscopic evaluation we used HE to asses the inflammatory process and the Sirius Red approach for collagens type I and III. Anti-CD 3 antibodies and anti-factor VIII assessed the concentration of T-lymphocytes and neovessels. the USHS caused greater cell damage with reepitelization delay. Microscopy showed more intense inflammatory reactions and a loss in collagen build up, delay in scar maturation and a greater vessel neoformation. USHS brings about a greater lesion in the incision area; delayed regeneration; promotes greater inflammatory process and angiogenic activity; delays in fibroplasia and scar tissue maturation on the rats' jugal mucosa when compared to cold blade scalpel.

Non-contact feature detection using ultrasonic Lamb waves

Science.gov (United States)

Sinha, Dipen N [Los Alamos, NM

2011-06-28

Apparatus and method for non-contact ultrasonic detection of features on or within the walls of hollow pipes are described. An air-coupled, high-power ultrasonic transducer for generating guided waves in the pipe wall, and a high-sensitivity, air-coupled transducer for detecting these waves, are disposed at a distance apart and at chosen angle with respect to the surface of the pipe, either inside of or outside of the pipe. Measurements may be made in reflection or transmission modes depending on the relative position of the transducers and the pipe. Data are taken by sweeping the frequency of the incident ultrasonic waves, using a tracking narrow-band filter to reduce detected noise, and transforming the frequency domain data into the time domain using fast Fourier transformation, if required.

Analysis of a Non-resonant Ultrasonic Levitation Device

Science.gov (United States)

Andrade, Marco A. B.; Pérez, Nicolás; Adamowski, Julio C.

In this study, a non-resonant configuration of ultrasonic levitation device is presented, which is formed by a small diameter ultrasonic transducer and a concave reflector. The influence of different levitator parameters on the levitation performance is investigated by using a numerical model that combines the Gor'kov theory with a matrix method based on the Rayleigh integral. In contrast with traditional acoustic levitators, the non-resonant ultrasonic levitation device allows the separation distance between the transducer and the reflector to be adjusted continually, without requiring the separation distance to be set to a multiple of half-wavelength. It is also demonstrated, both numerically and experimentally, that the levitating particle can be manipulated by maintaining the transducer in a fixed position in space and moving the reflector in respect to the transducer.

Signal Compression in Automatic Ultrasonic testing of Rails

Directory of Open Access Journals (Sweden)

Tomasz Ciszewski

2007-01-01

Full Text Available Full recording of the most important information carried by the ultrasonic signals allows realizing statistical analysis of measurement data. Statistical analysis of the results gathered during automatic ultrasonic tests gives data which lead, together with use of features of measuring method, differential lossy coding and traditional method of lossless data compression (Huffman’s coding, dictionary coding, to a comprehensive, efficient data compression algorithm. The subject of the article is to present the algorithm and the benefits got by using it in comparison to alternative compression methods. Storage of large amount  of data allows to create an electronic catalogue of ultrasonic defects. If it is created, the future qualification system training in the new solutions of the automat for test in rails will be possible.

Ultrasonic stress evaluation through thickness of a stainless steel pressure vessel

International Nuclear Information System (INIS)

Javadi, Yashar; Pirzaman, Hamed Salimi; Raeisi, Mohammadreza Hadizadeh; Najafabadi, Mehdi Ahmadi

2014-01-01

This paper investigates ultrasonic method in stress measurement through thickness of a pressure vessel. Longitudinal critically refracted (L CR ) waves are employed to measure the welding residual stresses in a vessel constructed from austenitic stainless steel 304L. The acoustoelastic constant is measured through a hydro test to keep the pressure vessel intact. Hoop and axial residual stresses are evaluated by using different frequency range of ultrasonic transducers. The welding processes of vessel shell and caps are simulated by a 3D finite element (FE) model which is validated by hole-drilling method. The residual stresses calculated by FE simulation are then compared with those obtained from the ultrasonic measurement while a good agreement is observed. It is demonstrated that the residual stresses through thickness of the stainless steel pressure vessel can be evaluated by combining FE and L CR method (known as FEL CR method). - Highlights: • The main goal is ultrasonic evaluation of through thickness stresses. • Welding processes of a stainless steel pressure vessel are modelled by FE. • The hole-drilling method is used to validate the FE results. • Residual stresses are measured by four different series of ultrasonic transducers. • The comparison between ultrasonic and FE results show an acceptable agreement

Ultrasonic extensometer measures bolt preload

Science.gov (United States)

Daniels, C. M., Jr.

1978-01-01

Extensometer using ultrasonic pulse reflections to measure elongations in tightened belts and studs is much more accurate than conventional torque wrenches in application of specified preload to bolts and other threaded fasteners.

Contributions regarding calculus and design of an ultrasonic system used in plasma metallization

Science.gov (United States)

Amza, G.

2015-11-01

Paper presents the calculus elements and construction for the ultrasonic system used in reconditioning process by metallization. A series of necessary elements used in ultrasonic system dimensioning are given and an ultrasonic system used in reconditioning process by plasma and grain metallization are presented. Also, a calculated ultrasonic system is modelled to work in resonance regime at the frequency f = 22Khz. Stress map inside material, internal energy variation, lost energy variation on length and volume unit are presented.

Burning Cold: Involvement of TRPA1 in Noxious Cold Sensation

OpenAIRE

Kwan, Kelvin Y.; Corey, David P.

2009-01-01

Soon after its discovery ten years ago, the ion channel TRPA1 was proposed as a sensor of noxious cold. Evidence for its activation by painfully cold temperatures (below ~15° C) has been mixed, however. Some groups found that cold elicits a nonselective conductance in cells expressing TRPA1; others found no activation, or argued that activation is an indirect effect of elevated \\(Ca^{ 2+}\\) . Sensory cells from the trigeminal and dorsal root ganglia that are activated by cold were sometimes c...

Damage to the edge of steel stampings and abrasive during ultrasonic hydroabrasive machining

International Nuclear Information System (INIS)

Dokuchaeva, V.A.; Chernov, A.P.

1976-01-01

Principles have been established explaining the fracture of abrasive material in the process of ultrasonic hydroabrasive treatment, and a method is proposed suitable for the calculation of steel barb erosion in the hydroabrasive flux. It is assumed that fracture occurs along the entire edge surface and that the losses caused by plastic deformation are small. Conclusion has been made as to the governing the change of the abrasive particle size in the time of treatment. It is shown that the most serious fracture takes place at initial stage of the treatment, terminating practically after 60 minutes of operation. Curves showing the distribution of boron carbide abrasive particles are presented