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Sample records for fung double tube

  1. Heat exchanger with leak detecting double wall tubes

    Science.gov (United States)

    Bieberbach, George; Bongaards, Donald J.; Lohmeier, Alfred; Duke, James M.

    1981-01-01

    A straight shell and tube heat exchanger utilizing double wall tubes and three tubesheets to ensure separation of the primary and secondary fluid and reliable leak detection of a leak in either the primary or the secondary fluids to further ensure that there is no mixing of the two fluids.

  2. Heat transfer in laminar flow for a finned double - tube

    International Nuclear Information System (INIS)

    Colle, S.

    1977-01-01

    An analitical study of the steady-state heat transfer in laminar flow in finned double-tube heat exchangers is presented. The fins are plane, straight and continous, equally spaced and are fixed over the external surface of the inner tube. A constant peripheral temperature distribution is assumed to apply over the inner tube surface and each fin, and a constant peripheral heat flux is assumed to apply over the outer tube surface, while the overall heat flux is suposed to be uniform in the longitudinal direction of the duct. The prediction of the thermal performance of the finned double-tube is made by means of the relationship between the Nusselt number, the boundary conditions and the geometric characteristcs of the duct. (author) [pt

  3. Performance analysis of double basin solar still with evacuated tubes

    International Nuclear Information System (INIS)

    Hitesh N Panchal; Shah, P. K.

    2013-01-01

    Solar still is a very simple device, which is used for solar distillation process. In this research work, double basin solar still is made from locally available materials. Double basin solar still is made in such a way that, outer basin is exposed to sun and lower side of inner basin is directly connected with evacuated tubes to increase distillate output and reducing heat losses of a solar still. The overall size of the lower basin is about 1006 mm x 325 mm x 380 mm, the outer basin is about 1006 mm x 536 mm x 100 mm Black granite gravel is used to increase distillate output by reducing quantity of brackish or saline water in the both basins. Several experiments have conducted to determine the performance of a solar still in climate conditions of Mehsana (latitude of 23 degree 59' and longitude of 72 degree 38'), Gujarat, like a double basin solar still alone, double basin solar still with different size black granite gravel, double basin solar still with evacuated tubes and double basin solar still with evacuated tubes and different size black granite gravel. Experimental results show that, connecting evacuated tubes with the lower side of the inner basin increases daily distillate output of 56% and is increased by 60%, 63% and 67% with average 10 mm, 20 mm and 30 mm size black granite gravel. Economic analysis of present double basin solar still is 195 days. (authors)

  4. Leak location in a double wall tube steam generator. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Greene, D.A.; McMurtrie, K.R.; Gaubatz, D.C.

    1980-01-01

    An experimental and analytical study was made of an acoustic location system for use with double wall tube steam generators. A conceptual design of an acoustic leak location system was developed. This system has the potential for detecting the third fluid gas escaping from the annulus between the double walled tubes into the sodium. The acoustic system uses an array of accelerometers mounted onto the outside of the steam generator vessel. Electronic circuitry selects a number of accelerometers, forms them into an array which focuses within the vessel. The volume of the vessel is sequentially scanned for anomalous acoustic energy.

  5. Research on liquid impact forming technology of double-layered tubes

    Science.gov (United States)

    Sun, Changying; Liu, Jianwei; Yao, Xinqi; Huang, Beixing; Li, Yuhan

    2018-03-01

    A double-layered tube is widely used and developed in various fields because of its perfect comprehensive performance and design. With the advent of the era of a double-layered tube, the requirements for double layered tube forming quality, manufacturing cost and forming efficiency are getting higher, so forming methods of a double-layered tube are emerged in an endless stream, the forming methods of a double-layered tube have a great potential in the future. The liquid impact forming technology is a combination of stamping technology and hydroforming technology. Forming a double-layered tube has huge advantages in production cost, quality and efficiency.

  6. Development of the double-wall-tube steam generator. Evaluation of inner tube leak detection system

    International Nuclear Information System (INIS)

    Teraoku, Takuji; Kisohara, Naoyuki

    1995-01-01

    A double-wall-tube steam generator (DWT-SG) is considered to have possibility of eliminating a secondary heat transport system to realize a reliable and simplified FBR plant. Thus, basic tests for inner/outer tube leak detection and prototypical leak tests by use of the 1MWt DWT-SG model have been performed to evaluate the feasibility of DWT-SG. Their results demonstrated that the inner leak detection system can definitely detect a steam leak from an inner tube flaw. Analyses of the inner tube leak and detection behavior obtained in the 1MWt DWT-SG test enabled to estimate the performance of the inner tube detection system of the commercial DWT-SG system. (author)

  7. Core design of super LWR with double tube water rods

    International Nuclear Information System (INIS)

    Wu, Jianhui; Oka, Yoshiaki

    2014-01-01

    Highlights: • Supercritical light water cooled and moderated reactor with double tube water rods is developed. • Double-row fuel rod assembly and out-in fuel loading pattern are applied. • Separation plates in peripheral assemblies increase average outlet temperature. • Neutronic and thermal design criteria are satisfied during the cycle. - Abstract: Double tube water rods are employed in core design of super LWR to simplify the upper core structure and refueling procedure. The light water moderator flows up in the inner tube from the bottom of the core, then, changes the flow direction at the top of the core into the outer tube and flows out at the bottom of the core. It eliminates the moderator guide/distribution tubes into the single tube water rods from the top dome of the reactor pressure vessel of the previous super LWR design. Two rows of fuel rods are filled between the water rods in the fuel assembly. Out-in refueling pattern is adopted to flatten radial power distribution. The peripheral fuel assemblies of the core are divided into four flow zones by separation plates for increasing the average core outlet temperature. Three enrichment zones are used for axial power flattening. The equilibrium core is analyzed based on neutronic/thermal-hydraulic coupled model. The results show that, by applying the separation plates in peripheral fuel assemblies and low gadolinia enrichment, the maximum cladding surface temperature (MCST) is limited to 653 °C with the average outlet temperature of 500 °C. The inherent safety is satisfied by the negative void reactivity effects and sufficient shutdown margin

  8. Shell-and-double concentric-tube heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Bougriou, Cherif; Baadache, Khireddine [University of Batna, Department of Mechanics, Batna (Algeria)

    2010-03-15

    This study concerns a new type of heat exchangers, which is that of shell-and-double concentric-tube heat exchangers. These heat exchangers can be used in many specific applications such as air conditioning, waste heat recovery, chemical processing, pharmaceutical industries, power production, transport, distillation, food processing, cryogenics, etc. The case studies include both design calculations and performance calculations. It is demonstrated that the relative diameter sizes of the two tubes with respect to each other are the most important parameters that influence the heat exchanger size. (orig.)

  9. Light Production in the Double Chooz Photomultiplier Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, E.; Cerrada, M.; Crespo, J. I.; Gil-Botella, I.; Jimenez, S.; Lopez, M.; Novella, P.; Palomares, C.; Santorelli, R.; Verdugo, A.

    2012-09-13

    In this document we present a study of the phenomenon of light emission (called glowing) in the bases of the Hamamatsu R7081MOD-ASSY photomultiplier tubes (PMTs) used in the Double Chooz experiment. The tests have been carried out at the CIEMAT laboratories over a photomultiplier tube of the same model. We have studied the phenomenon making first a characterization of it, and then focusing on the dependence of the rate and the amount of emitted light versus voltage and temperature. In addition, we have looked for the possible existence of an ultraviolet component in the light which would be harmful for the experiment because it could be able to excite the scintillator liquid. Finally, we propose and test a method to reduce the light emission using a cover on the base of the photomultiplier tube.. (Author)

  10. The single chest tube versus double chest tube application after pulmonary lobectomy: A systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Xuefei Zhang

    2016-01-01

    Conclusion: Compared with the double chest tube, the single chest tube significantly decreases amount of drainage, duration of chest tube drainage, pain score, the number of patients who need thoracentesis, and cost. Although there is convincing evidence to confirm the results mentioned herein, they still need to be confirmed by large-sample, multicenter, randomized, controlled trials.

  11. Thermal hydraulic characteristics of a double-walled tube advanced nuclear steam generator

    International Nuclear Information System (INIS)

    Cho, S.M.; Seltzer, A.H.

    1989-01-01

    In this paper the thermal hydraulic characteristics of double-walled tube steam generator designed for sodium-cooled nuclear reactors are presented. The double-walled tube construction, along with double-barrier welds for tube-to-tubesheet joints, virtually eliminates the probability of heat transfer tube failure. Considerations are given to the use of the internal core tube, helical vane swirl generator, external protector tube, and variably perforated flow baffles to improve thermal and hydraulic performance of the steam generator. These thermal hydraulic design features with a particular reference to a 432 MW PRISM steam generator are discussed

  12. Peptide signalling during the pollen tube journey and double fertilization.

    Science.gov (United States)

    Qu, Li-Jia; Li, Ling; Lan, Zijun; Dresselhaus, Thomas

    2015-08-01

    Flowering seed plants (angiosperms) have evolved unique ways to protect their gametes from pathogen attack and from drying out. The female gametes (egg and central cell) are deeply embedded in the maternal tissues of the ovule inside the ovary, while the male gametes (sperm cells) are enclosed in the vegetative pollen tube cell. After germination of the pollen tube at the surface of papilla cells of the stigma the two immobile sperm cells are transported deep inside the sporophytic maternal tissues to be released inside the ovule for double fertilization. Angiosperms have evolved a number of hurdles along the pollen tube journey to prevent inbreeding and fertilization by alien sperm cells, and to maximize reproductive success. These pre-zygotic hybridization barriers require intensive communication between the male and female reproductive cells and the necessity to distinguish self from non-self interaction partners. General molecules such as nitric oxide (NO) or gamma-aminobutyric acid (GABA) therefore appear to play only a minor role in these species-specific communication events. The past 20 years have shown that highly polymorphic peptides play a leading role in all communication steps along the pollen tube pathway and fertilization. Here we review our current understanding of the role of peptides during reproduction with a focus on peptide signalling during self-incompatibility, pollen tube growth and guidance as well as sperm reception and gamete activation. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  13. LBA Regional Wetlands Data Set, 1-Degree (Matthews and Fung)

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set is a subset of a global database compiled by Matthews and Fung (1987) on the distribution and environmental characteristics of natural wetlands. The...

  14. Shell and Double Concentric Tube Heat Exchanger Calculations and Analysis

    Directory of Open Access Journals (Sweden)

    Basma Abbas Abdulmajeed

    2015-01-01

    Full Text Available This study concerns a new type of heat exchangers, which is that of shell-and-double concentric tube heat exchangers. The case studies include both design calculations and performance calculations. The new heat exchanger design was conducted according to Kern method. The volumetric flow rates were 3.6 m3/h and 7.63 m3/h for the hot oil and water respectively. The experimental parameters studied were: temperature, flow rate of hot oil, flow rate of cold water and pressure drop. A comparison was made for the theoretical and experimental results and it was found that the percentage error for the hot oil outlet temperature was (- 1.6%. The percentage errors for the pressure drop in the shell and in the concentric tubes were (17.2% and (- 39% respectively. For cold water outlet temperature, the percentage error was (- 3.3%, while it was (18% considering the pressure drop in the annulus formed. The percentage error for the total power consumed was (-10.8% A theoretical comparison was made between the new design and the conventional heat exchanger from the point of view of, length, mass, pressure drop and total power consumed.

  15. Entropy Generation of Shell and Double Concentric Tubes Heat Exchanger

    Directory of Open Access Journals (Sweden)

    basma abbas abdulmajeed

    2016-06-01

    Full Text Available Entropy generation was studied for new type of heat exchanger (shell and double concentric tubes heat exchanger. Parameters of hot oil flow rate, temperature of inlet hot oil and pressure drop were investigated with the concept of entropy generation. The results showed that the value of entropy generation increased with increasing the flow rate of hot oil and when cold water flow rate was doubled from 20 to 40 l/min, these values were larger. On the other hand, entropy generation increased with increasing the hot oil inlet temperature at a certain flow rate of hot oil. Furthermore, at a certain hot oil inlet temperature, the entropy generation increased with the pressure drop at different hot oil inlet flow rates. Finally, in order to keep up with modern technology, infrared thermography camera was used in order to measure the temperatures. The entropy generation was determined with lower values when infrared thermography camera was used to measure the temperatures, compared with the values obtained by using thermocouples.

  16. Current Status on the Development of a Double Wall Tube Steam Generator

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ho Yun; Choi, Byoung Hae; Kim, Jong Man; Kim, Byung Ho

    2007-12-15

    A fast reactor, which uses sodium as a coolant, has a lot of merits as a next generation nuclear reactor. However, the possibility of a sodium-water reaction occurrence hinders the commercialization of this reactor. As one way to improve the reliability of a steam generator, a double-wall tube steam generator is being developed in GEN-4 program. In this report, the current state of the technical developments for a double-wall tube steam generator are reviewed and a future plan for the development of a double-wall tube steam generator is established. The current focuses of this research are an improvement of the heat transfer capability for a double-wall tube and the development of a proper leak detection method for the failure of a double-wall tube during a reactor operation. The ideal goal is an on-line leak detection of a double wall tube to prevent the sodium-water reaction. However, such a method is not developed as yet. An alternative method is being used to improve the reliability of a steam generator by performing a non-destructive test of a double wall tube during the refueling period of a reactor. In this method a straight double wall tube is employed to perform this test easily, but has a difficulty regarding an absorption of a thermal expansion of the used materials. If an on-line leak detection method is developed, the demerits of a straight double-wall tube are avoided by using a helical type double-wall tube, and the probability of a sodium-water reaction can be reduced to a level less than the design-based accident.

  17. Preliminary Study on Biosynthesis of Bacterial Nanocellulose Tubes in a Novel Double-Silicone-Tube Bioreactor for Potential Vascular Prosthesis.

    Science.gov (United States)

    Hong, Feng; Wei, Bin; Chen, Lin

    2015-01-01

    Bacterial nanocellulose (BNC) has demonstrated a tempting prospect for applications in substitute of small blood vessels. However, present technology is inefficient in production and BNC tubes have a layered structure that may bring danger after implanting. Double oxygen-permeable silicone tubes in different diameters were therefore used as a tube-shape mold and also as oxygenated supports to construct a novel bioreactor for production of the tubular BNC materials. Double cannula technology was used to produce tubular BNC via cultivations with Acetobacter xylinum, and Kombucha, a symbiosis of acetic acid bacteria and yeasts. The results indicated that Kombucha gave higher yield and productivity of BNC than A. xylinum. Bacterial nanocellulose was simultaneously synthesized both on the inner surface of the outer silicone tube and on the outer surface of the inner silicone tube. Finally, the nano BNC fibrils from two directions formed a BNC tube with good structural integrity. Scanning electron microscopy inspection showed that the tubular BNC had a multilayer structure in the beginning but finally it disappeared and an intact BNC tube formed. The mechanical properties of BNC tubes were comparable with the reported value in literatures, demonstrating a great potential in vascular implants or in functional substitutes in biomedicine.

  18. Preliminary Study on Biosynthesis of Bacterial Nanocellulose Tubes in a Novel Double-Silicone-Tube Bioreactor for Potential Vascular Prosthesis

    Directory of Open Access Journals (Sweden)

    Feng Hong

    2015-01-01

    Full Text Available Bacterial nanocellulose (BNC has demonstrated a tempting prospect for applications in substitute of small blood vessels. However, present technology is inefficient in production and BNC tubes have a layered structure that may bring danger after implanting. Double oxygen-permeable silicone tubes in different diameters were therefore used as a tube-shape mold and also as oxygenated supports to construct a novel bioreactor for production of the tubular BNC materials. Double cannula technology was used to produce tubular BNC via cultivations with Acetobacter xylinum, and Kombucha, a symbiosis of acetic acid bacteria and yeasts. The results indicated that Kombucha gave higher yield and productivity of BNC than A. xylinum. Bacterial nanocellulose was simultaneously synthesized both on the inner surface of the outer silicone tube and on the outer surface of the inner silicone tube. Finally, the nano BNC fibrils from two directions formed a BNC tube with good structural integrity. Scanning electron microscopy inspection showed that the tubular BNC had a multilayer structure in the beginning but finally it disappeared and an intact BNC tube formed. The mechanical properties of BNC tubes were comparable with the reported value in literatures, demonstrating a great potential in vascular implants or in functional substitutes in biomedicine.

  19. Preliminary Study on Biosynthesis of Bacterial Nanocellulose Tubes in a Novel Double-Silicone-Tube Bioreactor for Potential Vascular Prosthesis

    Science.gov (United States)

    Wei, Bin; Chen, Lin

    2015-01-01

    Bacterial nanocellulose (BNC) has demonstrated a tempting prospect for applications in substitute of small blood vessels. However, present technology is inefficient in production and BNC tubes have a layered structure that may bring danger after implanting. Double oxygen-permeable silicone tubes in different diameters were therefore used as a tube-shape mold and also as oxygenated supports to construct a novel bioreactor for production of the tubular BNC materials. Double cannula technology was used to produce tubular BNC via cultivations with Acetobacter xylinum, and Kombucha, a symbiosis of acetic acid bacteria and yeasts. The results indicated that Kombucha gave higher yield and productivity of BNC than A. xylinum. Bacterial nanocellulose was simultaneously synthesized both on the inner surface of the outer silicone tube and on the outer surface of the inner silicone tube. Finally, the nano BNC fibrils from two directions formed a BNC tube with good structural integrity. Scanning electron microscopy inspection showed that the tubular BNC had a multilayer structure in the beginning but finally it disappeared and an intact BNC tube formed. The mechanical properties of BNC tubes were comparable with the reported value in literatures, demonstrating a great potential in vascular implants or in functional substitutes in biomedicine. PMID:26090420

  20. Investigation of structural and electronic properties of double walled Zn O nano tube bundle

    International Nuclear Information System (INIS)

    Moradian, R.; Amjadian, S.; Shahrokhi, M.

    2012-01-01

    We have investigated the structural and electronic properties of isolated double walled Zn O nano tube and its bundle by the first principles calculations in the framework of the density functional theory based on the full-potential augmented plane-wave within the generalized gradient approximation. Our results show that bundle nano tube is more stable than isolated nano tube. In the bundle the inter-tube interaction between each wall with its nearest neighbors causes, band splitting and reduction of semiconducting energy gap.

  1. Enhancement of distillate output of double basin solar still with vacuum tubes

    Directory of Open Access Journals (Sweden)

    Hitesh N. Panchal

    2015-07-01

    Full Text Available In this research paper, attempts are made to make a double basin solar still. The overall size of the lower basin used is 1006 mm × 325 mm × 380 mm and the outer basin is 1006 mm × 536 mm × 100 mm. Black granite gravel is used to increase the distillate output by reducing the quantity of brackish or saline water in both basins. Several experiments have been conducted to determine the performance of a solar still in climate conditions of Mehsana (latitude of 23°59′ and longitude of 72° 38′, Gujarat. Here, three conditions used to determine the performance of double basin solar still like a double basin solar still alone, double basin solar still with black granite gravel, double basin solar still with vacuum tubes and double basin solar still with vacuum tubes and black granite gravel. Experimental results and comparison with other researchers show that, the daily distillate output increases by coupling vacuum tubes and by coupling vacuum tubes and black granite gravel to 56% and 65% respectively.

  2. The Bulging Behavior of Thick-Walled 6063 Aluminum Alloy Tubes Under Double-Sided Pressures

    Science.gov (United States)

    Cui, Xiao-Lei; Wang, Xiao-Song; Yuan, Shi-Jian

    2015-05-01

    To make further exploration on the deformation behavior of tube under double-sided pressures, the thick-walled 6063 aluminum alloy tubes with an outer diameter of 65 mm and an average thickness of 7.86 mm have been used to be bulged under the combined action of internal and external pressures. In the experiment, two ends of the thick-walled tubes were fixed using the tooth and groove match. Three levels of external pressure (0 MPa, 40 MPa, and 80 MPa), in conjunction with the internal pressure, were applied on the tube outside and inside simultaneously. The effect of external pressure on the bulging behavior of the thick-walled tubes, such as the limiting expansion ratio, the bulging zone profile, and the thickness distribution, has been investigated. It is shown that the limiting expansion ratio, the bulging zone profile, and the thickness distribution in the homogeneous bulging area are all insensitive to the external pressure. However, the external pressure can make the thick-walled tube achieve a thinner wall at the fracture area. It reveals that the external pressure can only improve the fracture limit of the thick-walled 6063 tubes, but it has very little effect on their homogeneous bulging behavior. It might be because the external pressure can only increase the magnitude of the hydrostatic pressure for the tube but has no effect on the Lode parameter.

  3. The Effect of Nanoparticles on Thermal Efficiency of Double Tube Heat Exchangers in Turbulent Flow

    OpenAIRE

    Aghayari, Reza; Madah, Heydar; Keyvani, Bahram; Moghadassi, Abdolreza; Ashori, Fatemeh

    2014-01-01

    This paper refers to the Overall Heat Transfer Coefficient of Nano Fluids (OHTCNF) in heat exchangers and the relevant effective parameters. An improvement in Heat Transfer (HT) and OHTCNF containing nanoaluminum oxide with ca. 20 nm particle size and particular volume fraction in the range of 0.001-0.002 has been reported. The effects of temperature and concentration of nanoparticles on HT variation as well as Overall Heat Transfer Coefficient (OHTC) in a countercurrent double tube heat exch...

  4. Double tube heat exchanger with novel enhancement: Part I - flow development length and adiabatic friction factor

    Energy Technology Data Exchange (ETDEWEB)

    Tiruselvam, R.; Raghavan, Vijay R. [Universiti Teknologi PETRONAS, Faculty of Mechanical Engineering, Tronoh (Malaysia)

    2012-04-15

    The study is conducted to evaluate the flow characteristics in a double tube heat exchanger using two new and versatile enhancement configurations. The novelty is that they are usable in single phase forced convection, evaporation and condensation. Correlations are proposed for flow development length and friction factor for use in predicting fluid pumping power in thermal equipment as well as in subsequent heat transfer characterization of the surface. (orig.)

  5. Description of a double centrifugation tube method for concentrating canine platelets

    OpenAIRE

    Perazzi, Anna; Busetto, Roberto; Martinello, Tiziana; Drigo, Michele; Pasotto, Daniela; Cian, Francesco; Patruno, Marco; Iacopetti, Ilaria

    2013-01-01

    Background To evaluate the efficiency of platelet-rich plasma preparations by means of a double centrifugation tube method to obtain platelet-rich canine plasma at a concentration at least 4 times higher than the baseline value and a concentration of white blood cells not exceeding twice the reference range. A complete blood count was carried out for each sample and each concentrate. Whole blood samples were collected from 12 clinically healthy dogs (consenting blood donors). Blood was proces...

  6. Evaluation of single and double centrifugation tube methods for concentrating equine platelets.

    Science.gov (United States)

    Argüelles, D; Carmona, J U; Pastor, J; Iborra, A; Viñals, L; Martínez, P; Bach, E; Prades, M

    2006-10-01

    The aim of this study was to evaluate single and double centrifugation tube methods for concentrating equine platelets. Whole blood samples were collected from clinically normal horses and processed by use of single and double centrifugation tube methods to obtain four platelet concentrates (PCs): PC-A, PC-B, PC-C, and PC-D, which were analyzed using a flow cytometry hematology system for hemogram and additional platelet parameters (mean platelet volume, platelet distribution width, mean platelet component concentration, mean platelet component distribution width). Concentrations of transforming growth factor beta 1 (TGF-beta(1)) were determined in all the samples. Platelet concentrations for PC-A, PC-B, PC-C, and PC-D were 45%, 44%, 71%, and 21% higher, respectively, compared to the same values for citrated whole blood samples. TGF-beta(1) concentrations for PC-A, PC-B, PC-C, and PC-D were 38%, 44%, 44%, and 37% higher, respectively, compared to citrated whole blood sample values. In conclusion, the single and double centrifugation tube methods are reliable methods for concentrating equine platelets and for obtaining potentially therapeutic TGF-beta(1) levels.

  7. Description of a double centrifugation tube method for concentrating canine platelets.

    Science.gov (United States)

    Perazzi, Anna; Busetto, Roberto; Martinello, Tiziana; Drigo, Michele; Pasotto, Daniela; Cian, Francesco; Patruno, Marco; Iacopetti, Ilaria

    2013-07-22

    To evaluate the efficiency of platelet-rich plasma preparations by means of a double centrifugation tube method to obtain platelet-rich canine plasma at a concentration at least 4 times higher than the baseline value and a concentration of white blood cells not exceeding twice the reference range. A complete blood count was carried out for each sample and each concentrate. Whole blood samples were collected from 12 clinically healthy dogs (consenting blood donors). Blood was processed by a double centrifugation tube method to obtain platelet concentrates, which were then analyzed by a flow cytometry haematology system for haemogram. Platelet concentration and white blood cell count were determined in all samples. Platelet concentration at least 4 times higher than the baseline value and a white blood cell count not exceeding twice the reference range were obtained respectively in 10 cases out of 12 (83.3%) and 11 cases out of 12 (91.6%). This double centrifugation tube method is a relatively simple and inexpensive method for obtaining platelet-rich canine plasma, potentially available for therapeutic use to improve the healing process.

  8. Double-lumen endotracheal tube positioning: Bag compliance Vs. fiberoptic bronchoscopy

    Directory of Open Access Journals (Sweden)

    Noyan Ashraf MA

    2012-11-01

    Full Text Available Background: Lung separation is the basis of thoracic anesthesia, which is performed by different instruments. Checking probable malpositioning of tracheal tube needs fiberoptic bronchoscopy. The aim of this study was to compare respirator suggested compliance with fiberoptic findings in detecting major tracheal tube malpositioning.Methods: A total of 256 patients undergoing thoracic surgery with double-lumen tracheal tube insertion in Imam Khomeini Hospital, Tehran, Iran, during 2010-11 were divided into three groups (n=86. We used left-sided double-lumen tube (DLT for left or right-sided surgeries (groups 1 and 2, and right-sided DLT for left-sided surgeries (group 3. The position of the tubes was evaluated and compared using bag compliance versus fiberoptic bronchoscopy.Results: The mean age of the study population was 44.7±13.4 (16-73 years, while 155 (59.9% were male. The sensitivity, specificity, positive and negative predictive values, and the accuracy of bag compliance test for left-sided DLT in supine position were 40% (95% CI: 20-60%, 99% (95% CI: 96-99%, 84% (95% CI: 54-94% 92% (95% CI: 88-95% and 92% (95% CI: 87-95%, respectively. The above-mentioned variables for lateral decubitus position respectively were 27%, 98%, 76%, 89%, and 88%. Malpositioning was more prevalent in right-sided DLTs (P=0.02.Conclusion: Based on the results of this study, and the high specificity, positive predictive value, and accuracy of bag compliance test, its use is encouraged as an alternative to fiberoptic bronchoscopy for checking DLT position, specially, in emergent surgeries or when fiberoptic bronchoscopy is unreachable due to lack of expertise or personnel.

  9. Male-female crosstalk during pollen germination, tube growth and guidance, and double fertilization.

    Science.gov (United States)

    Dresselhaus, Thomas; Franklin-Tong, Noni

    2013-07-01

    Sperm cells of flowering plants are non-motile and thus require transportation to the egg apparatus via the pollen tube to execute double fertilization. During its journey, the pollen tube interacts with various sporophytic cell types that support its growth and guide it towards the surface of the ovule. The final steps of tube guidance and sperm delivery are controlled by the cells of the female gametophyte. During fertilization, cell-cell communication events take place to achieve and maximize reproductive success. Additional layers of crosstalk exist, including self-recognition and specialized processes to prevent self-fertilization and consequent inbreeding. In this review, we focus on intercellular communication between the pollen grain/pollen tube including the sperm cells with the various sporophytic maternal tissues and the cells of the female gametophyte. Polymorphic-secreted peptides and small proteins, especially those belonging to various subclasses of small cysteine-rich proteins (CRPs), reactive oxygen species (ROS)/NO signaling, and the second messenger Ca(2+), play center stage in most of these processes.

  10. Double plasma arc in a graphite tube - application of discharge atmospheres

    International Nuclear Information System (INIS)

    Arens, C.; Nickel, H.; Mazurkiewicz, M.; Vukanovic, D.

    1981-01-01

    With a view to safety and economic efficiency element-specific limits are required for permissible impurities in reactor graphite. This leads to the necessity of developing suitable methods of analysis. Emission spectroscopy has proved to be a method of analysis featuring a high detection capability and offering the possibility of determining several elements simultaneously. A prolongation of the particle residence time in the plasma (and, thus, an increase in radiation intensity) was the objective when developing a novel spectrochemical source of excitation. The method uses two d.c. arcs burning in a horizontally arranged graphite tube. The double plasma arc in a graphite tube has proved to be an excellent source of excitation for the analysis of powder and solutions. (orig./IHOE)

  11. Anharmonic properties of Raman modes in double wall carbon nano tubes

    Energy Technology Data Exchange (ETDEWEB)

    Marquina, J. [Universidad de los Andes, Facultad de Ciencias, Centro de Estudios Avanzados en Optica, 5101 Merida (Venezuela, Bolivarian Republic of); Power, Ch.; Gonzalez, J. [Universidad de los Andes, Facultad de Ciencias, Centro de Estudios en Semiconductores, 5101 Merida (Venezuela, Bolivarian Republic of); Broto, J. M. [Universite de Toulouse, Laboratoire National des Champs Magnetiques Intenses, CNRS UPR 3228, 31400 Toulouse (France); Flahaut, E., E-mail: castella@ula.v [Universite Paul Sabatier, Laboratoire de Chimie des Materiaux Inorganiques, UMR CNRS 5085, 31062 Toulouse (France)

    2011-07-01

    The temperature dependence of the radial breathing modes (RB Ms) and the zone-center tangential optical phonons (G-bands) of double-walled carbon nano tubes has been investigated between 300 and 700 K using Raman scattering. As expected, with increasing temperature, the frequencies of the Raman peaks, including the RB Ms and G-bands downshift simultaneously. We show here that the temperature dependence of the RB Ms can be fitted by a simple linear dependence and different RB Ms have different frequency shifts. We observe a noticeable nonlinearity in the temperature dependence of the G-band associated with the outer semiconducting tube G+ext (s). The deviation from the linear trend is due to the contribution of the third-order anharmonic term in the lattice potential energy with a pure temperature effect. An estimated value of 1.5 for the Grueneisen parameter of the G+ext (s) band was found. (Author)

  12. Parametric study and performance analysis of hybrid rocket motors with double-tube configuration

    Science.gov (United States)

    Yu, Nanjia; Zhao, Bo; Lorente, Arnau Pons; Wang, Jue

    2017-03-01

    The practical implementation of hybrid rocket motors has historically been hampered by the slow regression rate of the solid fuel. In recent years, the research on advanced injector designs has achieved notable results in the enhancement of the regression rate and combustion efficiency of hybrid rockets. Following this path, this work studies a new configuration called double-tube characterized by injecting the gaseous oxidizer through a head end injector and an inner tube with injector holes distributed along the motor longitudinal axis. This design has demonstrated a significant potential for improving the performance of hybrid rockets by means of a better mixing of the species achieved through a customized injection of the oxidizer. Indeed, the CFD analysis of the double-tube configuration has revealed that this design may increase the regression rate over 50% with respect to the same motor with a conventional axial showerhead injector. However, in order to fully exploit the advantages of the double-tube concept, it is necessary to acquire a deeper understanding of the influence of the different design parameters in the overall performance. In this way, a parametric study is carried out taking into account the variation of the oxidizer mass flux rate, the ratio of oxidizer mass flow rate injected through the inner tube to the total oxidizer mass flow rate, and injection angle. The data for the analysis have been gathered from a large series of three-dimensional numerical simulations that considered the changes in the design parameters. The propellant combination adopted consists of gaseous oxygen as oxidizer and high-density polyethylene as solid fuel. Furthermore, the numerical model comprises Navier-Stokes equations, k-ε turbulence model, eddy-dissipation combustion model and solid-fuel pyrolysis, which is computed through user-defined functions. This numerical model was previously validated by analyzing the computational and experimental results obtained for

  13. Checklisten für die Durchführung der Umweltprüfung/Umweltbetriebsprüfung an Hochschulen im Rahmen der Einführung von Umweltmanagementsystemen. - 2003

    OpenAIRE

    Günther, Edeltraud; Fröhlich, Jürgen; Winkler, Ute; Klauke, Ines; Brömmer, Kathrin

    2003-01-01

    Mit der Validierung des Umweltmanagementsystems nach der EG-Öko-Audit-Verordnung (EMAS II) ist die TU Dresden die erste Technische Universität Deutschlands, die den Prozess der Einführung und Umsetzung eines Umweltmanagementsystems nach EMAS II erfolgreich durchlaufen hat. Im Rahmen des Öko-Audits an der TU Dresden wurden Checklisten zur Hilfestellung für die Durchführung der Umweltprüfung und Umweltbetriebsprüfung entwickelt. Die Durchführung der Umweltprüfung und Umweltbetriebsprüfung an de...

  14. Computation of Electromagnetic Torque in a Double Rotor Switched Reluctance Motor Using Flux Tube Methods

    Directory of Open Access Journals (Sweden)

    Mohammad Hamiruce Marhaban

    2012-10-01

    Full Text Available With their highly robust nature and simple design, switched reluctance machines are finding their way into numerous modern day applications. However, they produce oscillatory torque that generates torque ripple and mechanical vibrations. A double rotor structure to maximize the flux linkage and thereby increase the torque generating capability is proposed. As the machine operates close to saturation, the torque computation depends heavily on the energy conversion as the rotor rolls over the stator for a fixed pole pitch. The flux linkage characteristics are highly non-linear, hence estimation of the magnetic and mechanical parameters is extremely cumbersome. Magnetic circuit analysis by interpretation of the number of flux tubes using integration techniques at different positions of the machine to develop the flux linkage characteristics of the double rotor structure is presented. Computation of the inductances during the movement of rotor from unaligned to aligned is crucial in determining the generated torque. Relevant equations of calculations for inductance and flux linkages in the aligned, partially aligned and unaligned positions are computed. The partially aligned computation is based on the average on two intermediate positions, namely the 1/4th aligned and 3/4th aligned conditions. The static torque characteristics based on the energy conversion principles are used to compute the torque value. Results from simulation and experiments used for performance evaluation of the proposed flux tube analysis for computation of the electro-magnetic torque are presented.

  15. Performance improvements of the BNC tubes from unique double-silicone-tube bioreactors by introducing chitosan and heparin for application as small-diameter artificial blood vessels.

    Science.gov (United States)

    Li, Xue; Tang, Jingyu; Bao, Luhan; Chen, Lin; Hong, Feng F

    2017-12-15

    In order to improve property of bacterial nano-cellulose (BNC) to achieve the requirements of clinical application as small caliber vascular grafts, chitosan (CH) was deposited into the fibril network of the BNC tubes fabricated in unique Double-Silicone-Tube bioreactors. Heparin (Hep) was then chemically grafted into the BNC-based tubes using EDC/NHS crosslinking to improve performance of anticoagulation and endothelialization. Physicochemical and mechanical property, blood compatibility, and cytocompatibility were compared before and after compositing. The results indicated that strength at break was increased but burst pressure decreased slightly after compositing. Performance of the BNC tubes was improved remarkably after introducing chitosan and heparin. The EDC/NHS crosslinking catalyzed both amide bonds and ester bonds formation in the BNC/CH-Hep composites. Three-dimensional surface structure and roughness were firstly obtained and discussed in relation to the hemocompatibility of BNC-based tubes. This work demonstrates the heparinized BNC-based tubes have great potential in application as small-diameter vascular prosthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Structural Pre-sizing of a Coaxial Double-tube Type Hot Gas Duct

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kee Nam; Kim, Y-W [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-10-15

    The nuclear hydrogen system being researched at KAERI is planning to produce hydrogen in the order of 950 .deg. C by using nuclear energy and a thermo-chemical process, and helium gas is tentatively considered as the choice for the coolant. A hot gas duct (HGD) is a key component connecting the reactor pressure vessel and the intermediate heat exchanger (IHX) for the nuclear hydrogen system. The HGD is a unique component exclusively found in an HTR-module concept where a nuclear core and IHX are placed separately into two pressure vessels, which require a connecting duct between them. A coaxial double-tube type cross vessel is considered for the HGD structure of the nuclear hydrogen system because of its successive extensive experience. In this study, a structural pre-sizing for the primary HGD was carried out. These activities include a predecision on the geometric dimensions, a pre-evaluation on the strength, and a pre-selection on the material of the coaxial double-tube type cross vessel components. A predecision on the geometric dimensions was undertaken based on various engineering concepts, such as a constant flow velocity (CFV) model, a constant flow rate (CFR) model, a constant hydraulic head (CHH) model, and finally a heat balanced (HB) model. For the CFV model, CFR model, and CHH model, the HGD structure might be insensitive to a flow induced vibration (FIV) in the case where there are no pressure differences between the hot and cold helium regions. Also we compared the geometric dimensions from the various models.

  17. Computed Tomographic Window Setting for Bronchial Measurement to Guide Double-Lumen Tube Size.

    Science.gov (United States)

    Seo, Jeong-Hwa; Bae, Jinyoung; Paik, Hyesun; Koo, Chang-Hoon; Bahk, Jae-Hyon

    2018-04-01

    The bronchial diameter measured on computed tomography (CT) can be used to guide double-lumen tube (DLT) sizes objectively. The bronchus is known to be measured most accurately in the so-called bronchial CT window. The authors investigated whether using the bronchial window results in the selection of more appropriately sized DLTs than using the other windows. CT image analysis and prospective randomized study. Tertiary hospital. Adults receiving left-sided DLTs. The authors simulated selection of DLT sizes based on the left bronchial diameters measured in the lung (width 1,500 Hounsfield unit [HU] and level -700 HU), bronchial (1,000 HU and -450 HU), and mediastinal (400 HU and 25 HU) CT windows. Furthermore, patients were randomly assigned to undergo imaging with either the bronchial or mediastinal window to guide DLT sizes. Using the underwater seal technique, the authors assessed whether the DLT was appropriately sized, undersized, or oversized for the patient. On 130 CT images, the bronchial diameter (9.9 ± 1.2 mm v 10.5 ± 1.3 mm v 11.7 ± 1.3 mm) and the selected DLT size were different in the lung, bronchial, and mediastinal windows, respectively (p window suggested too small DLTs (28 Fr) for adults. In the prospective study, oversized tubes were chosen less frequently in the bronchial window than in the mediastinal window (6/110 v 23/111; risk ratio 0.38; 95% CI 0.19-0.79; p = 0.003). No tubes were undersized after measurements in these two windows. The bronchial measurement in the bronchial window guided more appropriately sized DLTs compared with the lung or mediastinal windows. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. "Detachment of the carinal hook following endobronchial intubation with a double lumen tube"

    Directory of Open Access Journals (Sweden)

    Rocha Ana C

    2011-10-01

    Full Text Available Abstract Background Carinal hooks increases difficulty at endotracheal intubation. Amputation of the carinal hook during passage and malpositioning of the tube to the hook are some of the potential problems related with left-sided Carlens double lumen tube (DLT. This article reports an amputation of the hook during a difficult selective intubation and aimed at calling the attention to complications associated with DLTs and the importance of fiberoptic bronchoscopy. Case presentation A 68 year-old woman was scheduled for right-sided thoracotomy in whom blind DLT insertion was performed. Narrowed trachea causes difficulty in rotating the DLT 90° counter-clockwise. After carinal hook was noticed upon visual inspection of the DLT, fiberoptic bronchoscopy was used to remove the missing part (with the use of forceps from the right mainstem bronchus. Conclusion Insertion of DLTs with carinal hook is associated with technical problems and potentially life-threatening hazards have discouraged their use. Fiberoptic evaluation and repositioning solves most of the problems. Although amputation of the carinal hook has not been previously reported, clinicians should be alert. This case report emphasizes the utility of the fiberoptic bronchoscopy in the operating theatre for placement, positioning and inspection of the carinal hook DLT.

  19. Fast, global, and entrepreneurial: supply chain management, Hong Kong style. An interview with Victor Fung. Interview by Joan Magretta.

    Science.gov (United States)

    Fung, V

    1998-01-01

    Li & Fung, Hong Kong's largest export trading company, has been an innovator in supply chain management--a topic of increasing importance to many senior executives. In this interview, chairman Victor Fung explains both the philosophy behind supply chain management and the specific practices that Li & Fung has developed to reduce costs and lead times, allowing its customers to buy "closer to the market." Li & Fung has been a pioneer in "dispersed manufacturing." It performs the higher-value-added tasks such as design and quality control in Hong Kong, and outsources the lower-value-added tasks to the best possible locations around the world. The result is something new: a truly global product. To produce a garment, for example, the company might purchase yarn from Korea that will be woven and dyed in Taiwan, then shipped to Thailand for final assembly, where it will be matched with zippers from a Japanese company. For every order, the goal is to customize the value chain to meet the customer's specific needs. To be run effectively, Victor Fung maintains, trading companies have to be small and entrepreneurial. He describes the organizational approaches that keep the company that way despite its growing size and geographic scope: its organization around small, customer-focused units; its incentives and compensation structure; and its use of venture capital as a vehicle for business development. As Asia's economic crisis continues, chairman Fung sees a new model of companies emerging--companies that are, like Li & Fung, narrowly focused and professionally managed.

  20. McGrath Series 5 videolaryngoscope vs Airtraq DL videolaryngoscope for double-lumen tube intubation

    Science.gov (United States)

    Wan, Li; Liao, Mingfeng; Li, Li; Qian, Wei; Hu, Rong; Chen, Kun; Zhang, Chuanhan; Yao, Wenlong

    2016-01-01

    Abstract Background: Many studies have shown Airtraq videolaryngoscope provided faster tracheal intubation and a higher success rate than other videolaryngoscopes. Recently, different types of videolaryngoscopes have been reported for use in double-lumen tube (DLT) intubation. However, the advantages and disadvantages between them remain undetermined for DLT intubation. In this study, we compared the Airtraq DL videolaryngoscope with the McGrath Series 5 videolaryngoscope for DLT intubation by experienced anesthesiologists. Methods: Ninety patients with expected normal airways were randomly allocated to either the Airtraq or McGrath group. The primary outcome was DLT intubation time. The secondary outcomes were glottic view, success rate, subjective ease of intubation (100-mm visual analog scale, 0 = easy; 100 = difficult), incidence of DLT malposition, and postoperative intubation-related complication. Results: The airway characteristics were comparable between the 2 groups. Cormack and Lehane grades significantly improved with the use of the McGrath and Airtraq videolaryngoscopes, compared with the Macintosh laryngoscope. The intubation success rate on the first attempt was 93% in the Airtraq group and 95% in the McGrath group (P > 0.05). The intubation time in the McGrath group is longer than that in the Airtraq group (39.9 [9.1]s vs 28.6 [13.6]s, P  0.05). Conclusions: When using videolaryngoscopes for DLT intubation, the Airtraq DL is superior to the McGrath Series 5 in intubation time, but it does not decrease intubation difficulty. PMID:28002347

  1. Double-lumen tubes and auto-PEEP during one-lung ventilation.

    Science.gov (United States)

    Spaeth, J; Ott, M; Karzai, W; Grimm, A; Wirth, S; Schumann, S; Loop, T

    2016-01-01

    Double-lumen tubes (DLT) are routinely used to enable one-lung-ventilation (OLV) during thoracic anaesthesia. The flow-dependent resistance of the DLT's bronchial limb may be high as a result of its narrow inner diameter and length, and thus potentially contribute to an unintended increase in positive end-expiratory pressure (auto-PEEP). We therefore studied the impact of adult sized DLTs on the dynamic auto-PEEP during OLV. In this prospective clinical study, dynamic auto-PEEP was determined in 72 patients undergoing thoracic surgery, with right- and left-sided DLTs of various sizes. During OLV, air trapping was provoked by increasing inspiration to expiration ratio from 1:2 to 2:1 (five steps). Based on measured flow rate, airway pressure (Paw) and bronchial pressure (Pbronch), the pressure gradient across the DLT (ΔPDLT) and the total auto-PEEP in the respiratory system (i.e. the lungs, the DLT and the ventilator circuit) were determined. Subsequently the DLT's share in total auto-PEEP was calculated. ΔPDLT was 2.3 (0.7) cm H2O over the entire breathing cycle. At the shortest expiratory time the mean total auto-PEEP was 2.9 (1.5) cm H2O (range 0-5.9 cm H2O). The DLT caused 27 to 31% of the total auto-PEEP. Size and side of the DLT's bronchial limb did not impact auto-PEEP significantly. Although the DLT contributes to the overall auto-PEEP, its contribution is small and independent of size and side of the DLT's bronchial limb. The choice of DLT does not influence the risk of auto-PEEP during OLV to a clinically relevant extent. DRKS00005648. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Zerstörungsfreie Prüfung von modernen Werkstoffen mit dynamischen Shearografie-Verfahren

    OpenAIRE

    Menner, Philipp

    2013-01-01

    Die Herausforderungen an die zerstörungsfreie Prüfung steigen mit der zunehmenden Verbreitung moderner Werkstoffe. Die ZfP-Methoden sollten nicht nur schnell und kontaktfrei arbeiten, sondern auch die in diesen Werkstoffen auftretenden neuen Defektarten zuverlässig erfassen. Elektronische Speckle-Pattern-Interferometrie (ESPI) kann unter Verwendung zeitabhängiger Anregungs- und Auswerte-Methoden viele dieser Anforderungen erfüllen, sie ist jedoch für industrielle Anwendungen nicht robust g...

  3. The important role of positioning in nasogastric tube insertion in unconscious patients: A prospective, randomised, double-blind study.

    Science.gov (United States)

    Zhao, Wangmiao; Ge, Chunyan; Zhang, Wanzeng; Sun, Zhaosheng; Li, Xiaowei

    2018-01-01

    To investigate whether positioning the body in a lateral decubitus position will facilitate nasogastric tube insertion in unconscious patients. Inserting a nasogastric tube into unconscious patients can be challenging because these patients cannot cooperate with the operator. The piriform sinus and arytenoid cartilage are the most commonly reported impaction sites. However, we found that the first impaction site was the backward displaced tongue when inserting a nasogastric tube in unconscious patients who often exhibited glossoptosis. Performing an intubation in the lateral decubitus position could make this procedure easy. This prospective, double-blind, parallel, randomised controlled trial was conducted in Hengshui City, Hebei Province, China. A total of 110 cases of unconscious patients were enrolled. The patients were randomly assigned to a conventional group (group C) or a lateral decubitus position group (group L). In group C, the nasogastric tube was inserted while the patients were in a supine position using the conventional technique, and in group L, the tube was inserted in a lateral decubitus position or further tilting the body to a prone decubitus position 20-30°. We discussed reasonable intubation methods in unconscious patients by comparing the success rate on first insertion, the overall success rate, the intubation time and the complication rates between the two groups. Group L had a higher success rate on first insertion and overall success rate than group C (p Nasogastric tube insertions in the lateral decubitus position are recommended in unconscious patients because of the higher success rate, reduced intubation time and lower complication rate. This study provides an effective method for nasogastric tube insertions in unconscious patients. © 2017 John Wiley & Sons Ltd.

  4. Multi-objective shape optimization of double pipe heat exchanger with inner corrugated tube using RSM method

    International Nuclear Information System (INIS)

    Han, Huai-Zhi; Li, Bing-Xi; Wu, Hao; Shao, Wei

    2015-01-01

    Integrated a fully developing three-dimensional heat transfer and flow model, a multi-objective optimization aims to fulfill the geometric design for double-tube heat exchangers with inner corrugated tube is investigated in this work with RSM. Dimensionless corrugation pitch (p/D), dimensionless corrugation height (H/D), dimensionless corrugation radius (r/D) and Reynolds number (Re) are considered as four design parameters. Considering the process parameters, the characteristic numbers involving heat transfer characteristic, resistance characteristic and overall heat transfer performance calculated by CFD, and are served as objective functions to the RSM (Nu c , f c , Nu c /Nu s , f c /f s and h in this paper). The results of optimal designs are a set of multiple optimum solutions, called 'Pareto optimal solutions'. It reveals the identical tendency of Nu c /Nu s and f c /f s reflecting the conflict between them that means augmenting the heat transfer performance with various design parameters in the optimal situation inevitably sacrificed the increase of flow resistance. According to the Pareto optimal curves, the optimum designing parameters of double pipe heat exchanger with inner corrugated tube under the constrains of Nu c /Nu s ≥1.2 are found to be P/D = 0.82, H/D = 0.22, r/D = 0.23, Re = 26,263, corresponding to the maximum value of η = 1.12. (authors)

  5. Finite element implementation of a generalized Fung-elastic constitutive model for planar soft tissues.

    Science.gov (United States)

    Sun, Wei; Sacks, Michael S

    2005-11-01

    Numerical simulations of the anisotropic mechanical properties of soft tissues and tissue-derived biomaterials using accurate constitutive models remain an important and challenging research area in biomechanics. While most constitutive modeling efforts have focused on the characterization of experimental data, only limited studies are available on the feasibility of utilizing those models in complex computational applications. An example is the widely utilized exponential constitutive model proposed by Fung. Although present in the biomechanics literature for several decades, implementation of this model into finite element (FE) simulations has been limited. A major reason for limited numerical implementations are problems associated with inherent numerical instability and convergence. To address this issue, we developed and applied two restrictions for a generalized Fung-elastic constitutive model necessary to achieve numerical stability. These are (1) convexity of the strain energy function, and (2) the condition number of material stiffness matrix set lower than a prescribed value. These constraints were implemented in the nonlinear regression used for constitutive model parameter estimation to the experimental biaxial mechanical data. We then implemented the generalized Fung-elastic model into a commercial FE code (ABAQUS, Pawtucket, RI, USA). Single element and multi-element planar biaxial test simulations were conducted to verify the accuracy and robustness of the implementation. Results indicated that numerical convergence and accurate FE implementation were consistently obtained. The present study thus presents an integrated framework for accurate and robust implementation of pseudo-elastic constitutive models for planar soft tissues. Moreover, since our approach is formulated within a general FE code, it can be straightforwardly adopted across multiple software platforms.

  6. Use of GlideScope for double lumen endotracheal tube insertion in an awake patient with difficult airway.

    Science.gov (United States)

    Onrubia, X; Lluch-Oltra, A; Armero, R; Baldó, J

    2014-01-01

    There is scientific evidence that an anticipated difficult airway must be managed with the patient being awake. The GlideScope has been proven to be a useful device to intubate the trachea in some instances when difficult airway is present, and particularly in the awake patient. It has also been used for double lumen tube (DLT) in the anaesthetized patient, but its use with DLT in both circumstances, awake patients with difficult airway has not been described. GlideScope enabled us to achieve accurate local anesthetic spraying and a successful endotracheal intubation with a double lumen tube (DLT) in an awake patient with predicted difficult airway and bronchoaspiration risk. Different ways to resolve cases like this can be found in the anesthetic literature, but we think this could be another option to bear in mind. We also describe a new variation in the maneuver of introducing a DLT into the trachea under GlideScope view as DLT presents with some difficulties when introduced under normal circumstances. This option could add some risk for the patients when used in inexperienced hands and there is not sufficient scientific evidence in the literature to recommend it for all cases. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  7. Improving the double quantum filtered COSY experiment by "Moving Tube" NMR.

    Science.gov (United States)

    Donovan, Kevin J; Allen, Mary; Martin, Rachel W; Shaka, A J

    2012-06-01

    Most 2D NMR spectra show artifacts that become increasingly more prominent as the relaxation delay between transients is decreased. Additionally, "rushing" a 2D experiment may lead to reduced sensitivity. It is shown here how to collect a DQF-COSY spectrum in less time, without artifacts, and with improved sensitivity, by a hardware solution we call Moving Tube NMR (MT NMR): the sample volume is physically moved out of the receiver coil after each transient and replaced by a fresh aliquot that is nearer to the equilibrium magnetization M(0). MT NMR was implemented with an automated mechanism that gave accurate and reproducible vertical tube movement, and a very long 5mm outer diameter (OD) NMR tube to hold a larger sample volume. Comparison of conventional and MT NMR DQF-COSY showed increased sensitivity and far reduced artifacts in the latter. The so-called t(1)-noise in the MT spectrum was no worse than in the conventional spectrum, pointing to the excellent specifications of the long 5mm OD tube, and the good mechanical handling of the automated drive. Thus, MT NMR could improve throughput for routine 2D NMR experiments without reducing sensitivity or adding artifacts, if sufficient sample is available. MT NMR could also be useful in cases of limited solubility, or for nuclei with long T(1) relaxation times. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. COMPARISON OF DOUBLE AND SINGLE PIERCING PROCESS IN SEAMLESS STEEL TUBE MANUFACTURE

    OpenAIRE

    Chihiro, HAYASHI; Tomio, YAMAKAWA; Corporate Research and Development Laboratories, Sumitomo Metal Industries, Ltd.; Corporate Research and Development Laboratories, Sumitomo Metal Industries, Ltd.

    1997-01-01

    An investigation work was made on the influence of the piercing process on the rotary forging effects, redundant shear deformations and power consumption. In this work, a study was made to compare the double and single piercing process with reference to the Mannesmann piercing mill and the cone-type piercing mill developed by the authors. If the conventional double piercing process employing the Mannesmann piercing mill is replaced by the single piercing process employing the cone-type pierci...

  9. The effects of thermal softening of double-lumen endobronchial tubes on postoperative sore throat, hoarseness and vocal cord injuries: a prospective double-blind randomized trial.

    Science.gov (United States)

    Seo, J-H; Cho, C W; Hong, D M; Jeon, Y; Bahk, J-H

    2016-02-01

    It is well known that thermal softening of polyvinyl chloride tracheal tubes reduces nasal damage during nasotracheal intubation. We hypothesized that thermal softening of double-lumen endobronchial tubes (DLTs) may be effective for reducing airway injury. This randomized double-blind study was performed to investigate whether thermal softening of DLTs decreased postoperative sore throat, hoarseness or vocal cord injuries. Patients (n=140) undergoing one lung anaesthesia were randomized into two groups (n=70 each) depending on whether the DLT was softened by warming or not before tracheal intubation. The DLTs were placed in warm saline [40(1)°C] in the thermal softening group or in room temperature saline in the control group for 10 min. The vocal cords were examined by using flexible laryngoscopy immediately after extubation. Sore throat and hoarseness were evaluated for three postoperative days. The primary outcomes were the incidence of sore throat, hoarseness, and vocal cord injuries. Sore throat and vocal cord injuries occurred less frequently in the thermal softening group than in the control group [14/70 vs 27/70, risk ratio (95% CI): 0.52 (0.30-0.90), P=0.025 for sore throat; 15/70 vs 27/70, risk ratio (95% CI): 0.56 (0.32-0.95), P=0.042 for vocal cord injuries]. However, the incidence of hoarseness was comparable between the two groups. Tracheal intubation with DLTs softened by warming decreased the postoperative incidence of sore throat and vocal cord injuries. Therefore, thermal softening of DLTs before intubation seems to be helpful in reducing airway injuries associated with DLT intubation. NCT 01626365. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. In situ Raman spectroelectrochemistry as a tool for the differentiation of inner tubes of double-wall carbon nanotubes and thin single-wall carbon nanotubes.

    Science.gov (United States)

    Kalbác, Martin; Kavan, Ladislav; Dunsch, Lothar

    2007-12-01

    In situ Raman spectroelectrochemistry has been used to distinguish between thin single-wall carbon nanotubes (SWCNT) and the inner tubes of double-wall carbon nanotubes (DWCNT). The spectroelectrochemical method is based on the different change of the electronic structure of the inner tube in DWCNT and that of SWCNT during electrochemical charging, which is reflected in the Raman spectra. During electrochemical charging the inner tubes of DWCNT exhibit a delayed attenuation of the intensities of their Raman modes as referred to the behavior of SWCNT of similar diameter. The changes are pronounced for the radial breathing mode (RBM), and thus, these modes are diagnostic for the distinction of inner tubes of DWCNT from the thin SWCNT. The different sensitivities of inner and outer tubes to the applied electrochemical charging is a simple analytical tool for differentiation of SWCNT and DWCNT in a mixture. The significance of the proposed method is demonstrated on a commercial DWCNT sample.

  11. Evaluation of Continuous Irrigation and Drainage with a Double-Cavity Sleeve Tube to Treat Brain Abscess.

    Science.gov (United States)

    Yang, Zhenxing; Du, Li; Liu, Renzhong; Jian, Zhihong; Wan, Yu

    2017-10-01

    Brain abscesses carries a high morbidity and mortality, and despite medical advances, it continues to pose diagnostic and therapeutic challenges worldwide. The traditional surgical approaches to treating brain abscess (burr hole aspiration and craniotomy) have both advantages and disadvantages and remain controversial. Here we report a single institution's experience with a new surgical approach for brain abscess. We retrospectively analyzed 46 patients with intracranial abscess who underwent continuous irrigation and drainage through a double-cavity sleeve tube placed surgically in conjunction with a 4-week course of intravenous cefotaxime and metronidazole at Renmin Hospital of Wuhan University between January 2008 and December 2016. The patients' medical records were analyzed for demographic data, clinical presentation, predisposing factors, imaging findings, microbiological test results, treatments, surgical techniques, and outcomes. The 46 patients included 29 males and 17 females, ranging in age from 22 to 74 years. A single abscess was detected in 34 patients, whereas 12 patients had multiple abscesses. The average duration of hospitalization was 12.6 days. After treatment, 38 of the 46 patients resumed a normal life despite minor deficits (Glasgow Outcome Score [GOS] 5), 6 patients exhibited slight neurologic deficits (GOS 4), and 2 patients died of severe systemic infection and multiorgan failure. In particular, a patient with a brain abscess broken into the ventricle recovered well (GOS 5). No patient required repeat aspiration or surgical excision. Continuous brain abscess cavity irrigation and drainage with a double-cavity sleeve tube is an effective treatment for brain abscess and produces excellent results, especially for an abscess broken into the ventricle. It combines the advantages of burr hole aspiration and open craniotomy excision. It is easy to perform and reduces costs and damage to the patient, and also shortens hospitalization time and

  12. Efficiency, efficacy, and safety of EZ-blocker compared with left-sided double-lumen tube for one-lung ventilation

    NARCIS (Netherlands)

    Mourisse, J.M.; Liesveld, J.; Verhagen, A.F.T.M.; Rooij, G. van; Heide, S. van der; Schuurbiers, O.C.J.; Heijden, E. van der

    2013-01-01

    BACKGROUND: Double-lumen tubes (DLTs) or bronchial blockers are commonly used for one-lung ventilation. DLTs are sometimes difficult or even impossible to introduce, and the incidence of postoperative hoarseness and airway injuries is higher. Bronchial blockers are more difficult to position and

  13. Does nebulized lidocaine reduce the pain and distress of nasogastric tube insertion in young children? A randomized, double-blind, placebo-controlled trial.

    Science.gov (United States)

    Babl, Franz E; Goldfinch, Christopher; Mandrawa, Christine; Crellin, Dianne; O'Sullivan, Ronan; Donath, Susan

    2009-06-01

    Nasogastric tube insertion is a common procedure in children that is very painful and distressing. Although nebulized lidocaine has been shown to be effective in reducing the pain and discomfort of nasogastric tube insertion in adults, there have been no similar studies in children. We set out to investigate the role of nebulized lidocaine in reducing pain and distress of nasogastric tube insertion in young children. We conducted a randomized, double-blind, placebo-controlled trial of nebulized 2% lidocaine at 4 mg/kg versus saline placebo during nasogastric tube insertion at a tertiary urban pediatric emergency department. Patients were eligible if they were aged from 1 to 5 years with no comorbid disease and a clinical indication for a nasogastric tube. Nebulization occurred for 5 minutes, 5 minutes before nasogastric tube insertion. Video recordings before, during, and after the procedure were rated using the Face, Legs, Activity, Cry, and Consolability (FLACC) pain and distress assessment tool (primary outcome measure) and pain and distress visual analog scale scores (secondary outcome measures). Difficulty of insertion and adverse events were also assessed. Eighteen participants were nebulized with 2% lidocaine and 18 participants with normal saline. Nebulization was found to be highly distressing. FLACC scores during nasogastric tube insertion were very high in both groups. There was a trend in the post-nasogastric tube insertion period toward lower FLACC scores in the lidocaine group. Visual analog scale scores for this postinsertion period were significantly lower in the lidocaine arm for pain and distress. There were no significant differences between groups in terms of difficulty of insertion and the number of minor adverse events. The study was terminated early because of the distress and treatment delay associated with nebulization. Nasogastric tube insertion results in very high FLACC scores irrespective of lidocaine use. Nebulized lidocaine cannot be

  14. Flow instability research on steam generator with straight double-walled heat transfer tube for FBR. Pressure drop under high pressure condition

    International Nuclear Information System (INIS)

    Liu, Wei; Tamai, Hidesada; Yoshida, Hiroyuki; Takase, Kazuyuki; Hayafune, Hiroki; Futagami, Satoshi; Kisohara, Naoyuki

    2008-01-01

    For the Steam Generator (SG) with straight double-walled heat transfer tube that used in sodium cooled Faster Breeder Reactor, flow instability is one of the most important items need researching. As the first step of the research, thermal hydraulics experiments were performed under high pressure condition in JAEA with using a straight tube. Pressure drop, heat transfer coefficients and void fraction data were derived. This paper evaluates the pressure drop data with TRAC-BF1 code. The Pffan's correlation for single phase flow and the Martinelli-Nelson's two-phase flow multiplier are found can be well predicted the present pressure drop data under high pressure condition. (author)

  15. Combination of intravenous dexmedetomidine with topicalization of airway for placement of double lumen tube in a spontaneously breathing patient of giant lung bullae

    Directory of Open Access Journals (Sweden)

    Vikas Karne

    2016-10-01

    Here we present a patient with giant lung bulla in left lower lobe with severely reduced pulmonary reserves and significant air-trapping posted for VAT assisted bullectomy. Anaesthesia challenges including pathological changes, its effects during induction of anaesthesia, and issues related to placement of double lumen tube in a spontaneously breathing patient are discussed with possible advantages of dexmedetomidine in this special group of patients.

  16. Characterization of Multiaxial Stress-Strain Response of Tube Metal from Double-Sided Hydro-Bulging Test Based on Hosford's 1979 Yield Criterion

    Science.gov (United States)

    Cui, Xiao-Lei; Yang, Zhai-Ping; Wang, Xiao-Song

    2017-05-01

    To further explore the characterization of the multiaxial stress-strain responses of anisotropic tube metal from double-sided hydro-bulging tests, an analytical model for the equivalent stress and equivalent strain calculation was derived based on Hosford's 1979 yield criterion. Furthermore, thin-walled 5052-O aluminum alloy tubes were used to conduct the bulging experiment with an external pressure of 85 MPa. After the experimental data were substituted into the above analytical model, the Voce equation was used to fit the equivalent stress-strain relationship. It is concluded that the stress versus strain curves of the 5052-O tubes are strongly dependent on the loaded stress states, the adopted yield criteria, and the anisotropy coefficients. The external pressure of 85 MPa had little or no effect on the stress versus strain curves of the tubes, but the locations of the multiaxial stress versus strain curves were lower than that of the uniaxial stress versus strain curve. Moreover, the curve from Hosford's 1979 yield criterion not only had a higher saturation stress and material constant value than the curve from Mises and Hill's 1948 yield criteria but also had a dependence on the anisotropy coefficient.

  17. Intrathoracic esophageal replacement in the dog with the use of an artificial esophagus composed of a collagen sponge with a double-layered silicone tube.

    Science.gov (United States)

    Yamamoto, Y; Nakamura, T; Shimizu, Y; Matsumoto, K; Takimoto, Y; Kiyotani, T; Sekine, T; Ueda, H; Liu, Y; Tamura, N

    1999-08-01

    Intrathoracic esophageal replacement with an artificial esophagus is considered difficult. We attempted to replace the intrathoracic esophagus with an artificial esophagus composed of a collagen sponge with a double-layered silicone tube and examined the state of host tissue regeneration. A 5-cm long gap was created in the intrathoracic esophagus in 9 dogs and repaired by interposition of our prosthesis. The dogs were fed only by intravenous hyperalimentation for 28 days. The silicone tube was removed at 29 days after the operation, and oral feeding was reintroduced. One dog was put to death at each of the following times: 1, 2, 3, 3, 6, 12, and 24 months after the operation. One dog is still surviving without problems after more than 26 months. One dog died of malnutrition at 10 months. In all dogs, the host regenerated tissue had replaced the resulting gap at the time of silicone tube removal. The mucosa had fully regenerated within 3 months and the glands within 12 months. The process of stenosis and shrinkage was complete within 3 months and did not advance thereafter. The lamina muscularis mucosae were observed as islets of smooth muscle within 12 months. Although the skeletal muscle regenerated close to the anastomoses, it did not extend to the middle of the regenerated esophagus even after 24 months. Use of a collagen sponge with a double-layered silicone tube was shown to be feasible even in the thorax and to allow the regenerated host tissue, consisting of the mucosa, glands, and lamina muscularis mucosae, to replace the esophageal gap.

  18. Glidescope versus Airtraq DL for double-lumen tracheal tube insertion in patients with a predicted or known difficult airway: A randomised study.

    Science.gov (United States)

    Belze, Olivier; Lepage, Evan; Bazin, Yvan; Kerourin, Pierre; Fusciardi, Jacques; Remérand, Francis; Espitalier, Fabien

    2017-07-01

    Double-lumen tracheal tube (DLT) insertion can be managed with videolaryngoscopes such as the Glidescope or indirect laryngoscopes like the Airtraq DL. No study has compared both devices when a difficult intubation is predicted. Our hypothesis was that the Glidescope is superior to the Airtraq for double-lumen tube insertion in patients with a predicted or known difficult airway. Randomised study. Adults scheduled for thoracic elective surgery, requiring one-lung ventilation with a predicted difficult intubation score of at least 7 (Arné risk index). Between March 2014 and March 2015, adult patients, scheduled for elective thoracic surgery, requiring double-lumen tracheal tube placement, and with a predicted risk (evaluated preoperatively using the Arné score) or a history of difficult intubation, were allocated to a Glidescope or an Airtraq group. The primary outcome was the overall success rate of tracheal intubation after two attempts. Secondary outcomes were success rates on the first attempt, duration of intubation, need for laryngeal pressure, Cormack and Lehane grade and side-effects. Of 277 patients, 78 were predicted to have a difficult airway. Finally, 72 patients were enrolled. Neither the overall success rates of tracheal intubation [Glidescope group 31/36 (86%) versus Airtraq group 34/36 (94%), P = 0.43] nor the side-effects differed between groups. There was no difference concerning visualisation of the glottis using the Cormack and Lehane grade (P = 0.18) or intubation time [Glidescope group 67 s (49 to 90) versus Airtraq group 81 s (59 to 101), P = 0.28]. All patients with a previous history of difficult intubation were intubated successfully. There is no difference in success rates of tracheal intubation with a double-lumen tube in patients with a predicted or known difficult airway when using either a Glidescope or Airtraq device. National register of the French National Agency for Medicines and Health Products Safety No. 2014-A

  19. Comparison of the Airtraq laryngoscope and the GlideScope for double-lumen tube intubation in patients with predicted normal airways: a prospective randomized trial.

    Science.gov (United States)

    Yi, Jie; Gong, Yahong; Quan, Xiang; Huang, Yuguang

    2015-04-28

    The Airtraq laryngoscope and the GlideScope are commonly used in many airway scenarios. However, their features have not been fully described for double-lumen tube intubation. A prospective randomized study was designed to compare their intubation performances in thoracic surgery patients. Seventy ASA physical status I and II patients with predicted normal airway were scheduled for thoracic surgeries with double-lumen tube intubation. They were randomly assigned to one of two groups and intubated with either the Airtraq laryngoscope (group A, n = 35) or the GlideScope (group G, n = 35). Airway assessments were performed prior to anesthesia, and all patients were induced with a standard anesthetic regimen. The Cormack-Lehane grades were initially evaluated with a Macintosh laryngoscope and subsequently with the group-specific laryngoscope before intubation. Intubation time was recorded as the primary outcome. The Cormack-Lehane grade, the success of the first intubation attempt, the intubation difficulty scales and ease of tube advancement were noted. Hemodynamic variables during intubation and incidence of post-operative sore throat were documented as well. The intubation time of group A was shorter than that of group G (36.6 ± 20.2 s vs. 54.6 ± 25.7 s, p = 0.002). The Cormack-Lehane grade (I/II/III/IV) was significantly better in group A (33/2/0/0 vs. 28/7/0/0, p = 0.042). The mean arterial pressure and heart rate rose to higher levels during intubation with the GlideScope than with the Airtraq laryngoscope. The success of the first intubation attempt and the intubation difficulty scales were comparable between the two groups. The numbers of patients who experienced postoperative sore throat were similar (6 vs. 8) in the two groups. Compared with the GlideScope, the specially designed Airtraq laryngoscope might be more suitable for double-lumen tube intubations in patients with predicted normal airway. www.chictr.org Identifier: Chi

  20. Vocal Fold Adjustment Caused by Phonation Into a Tube: A Double-Case Study Using Computed Tomography

    Czech Academy of Sciences Publication Activity Database

    Hampala, V.; Laukkanen, A. M.; Guzman, M.; Horáček, Jaromír; Švec, J. G.

    2015-01-01

    Roč. 29, č. 6 (2015), s. 733-742 ISSN 0892-1997 R&D Projects: GA ČR(CZ) GAP101/12/1306 Institutional support: RVO:61388998 Keywords : vocal folds * resonance tube * computed tomography Subject RIV: BI - Acoustics Impact factor: 1.113, year: 2015 http://ac.els-cdn.com/S0892199714002756/1-s2.0-S0892199714002756-main.pdf?_tid=58e41ed4-d4be-11e5-b79c-00000aab0f01&acdnat=1455635150_c180f8db4970456952fb802bf329392b

  1. Replacing a double-lumen tube with a single-lumen tube or a laryngeal mask airway device to reduce coughing at emergence after thoracic surgery: a randomized controlled single-blind trial.

    Science.gov (United States)

    Tanoubi, Issam; Sun, Joanna Ng Man; Drolet, Pierre; Fortier, Louis-Philippe; Donati, François

    2015-09-01

    Coughing episodes occur frequently at extubation after thoracic surgery, and this may be due in part to the double-lumen tube (DLT). In this study, the DLT was replaced with either a single-lumen endotracheal tube (ETT) or a laryngeal mask airway (LMA) device or left in place, and the incidence of coughing at emergence was compared between the three groups. Fifty-eight adults scheduled for thoracic surgery with a DLT were included. Exclusion criteria were an anticipated difficult airway, obesity, and contraindication to the use of an LMA ProSeal™ (LMA-P). After surgery but before emergence, patients were randomized to having the DLT (1) removed and replaced by an LMA-P (LMA-P Group), (2) removed and replaced by an ETT (ETT Group), or (3) left in place (DLT Group). The primary outcome was the number of coughing episodes at extubation. Among 184 patients screened, 124 did not meet inclusion criteria, and two patients, both in the ETT Group, were excluded after randomization, leaving 20, 18, and 20 patients in the LMA-P, ETT, and DLT Groups, respectively. There were fewer coughing episodes (median [quartiles]) in the LMA-P Group than in the DLT Group (0[0-1] vs 2[1-3], respectively; P = 0.01). In the DLT Group, 90% of patients coughed at least once. This incidence was not significantly different in the ETT Group (83%; P = 0.222) but was significantly reduced in the LMA-P Group (35%; P replaced by an LMA-P before emergence. The number of patients in this trial was too small to evaluate the risks associated with exchanging the airway device. This trial was registered at ClinicalTrials.gov: NCT00925613.

  2. A randomized study comparing three bronchial blockers, Arndt®, Coopdech® and EZ-blocker® and a double-lumen tube for lung isolation : A manikin study

    NARCIS (Netherlands)

    Mungroop, H. E.; Gennep, L.; Morei, N.; Scheeren, T.; Epema, A. H.

    2011-01-01

    Background and Goal of Study: Double-lumen tubes (DLT) and bronchial blockers (BB) are used for lung isolation and one lung ventilation during thoracic surgery. Recently1 a new Y shaped bronchial blocker was developed, the EZ-Blocker, with two distal extensions to be placed in the two main

  3. Validierung der Wirksamkeitsprüfung für Clostridium tetani Impfstoffe ad usum veterinarium durch den direkten Nachweis von Tetanus-Antitoxin im Zieltier mittels ELISA

    OpenAIRE

    Roßkopf, Ute

    2007-01-01

    Die dargelegten Ergebnisse zur Validierung einer neuen Wirksamkeitsprüfung von Tetanus-Impfstoffen resultieren aus umfangreichen Feldstudien, durchgeführt mit neun unterschiedlichen Impfstoffen für das Pferd sowie acht Impfstoffen für das Schaf. Insgesamt wurden 102 Pferde und 82 Schafe entsprechend den Angaben in der Gebrauchsinformation immunisiert. Blutentnahmen fanden nach einem vorgegebenen Schema von bis zu zwei Jahren nach der ersten Impfung statt. Die Impfstoffe waren entweder monoval...

  4. Performance Evaluation of AI2O3/Water Nanofluid as Coolant in a Double-Tube Heat Exchanger Flowing under a Turbulent Flow Regime

    Directory of Open Access Journals (Sweden)

    Navid Bozorgan

    2012-01-01

    Full Text Available Nanofluids are expected to be a promising coolant candidate in chemical processes for water waste remediation and heat transfer system size reduction. This paper focuses on the potential mass flowrate reduction in exchanger with a given heat exchange capacity using nanofluids. Al2O3 nanoparticles with diameters of 7 nm dispersed in water with volume concentrations up to 2% are selected as a coolant, and their performance in a horizontal double-tube counterflow heat exchanger under turbulent flow conditions is numerically studied. The results show that the flowrate of nanofluid coolant decreases with the increase of concentration of nanoparticles in the exchanger with a given heat exchange capacity. The mass flowrate of the nanofluid at a volume concentration of 2 vol.% is approximately 24.5% lower than that of pure water (base fluid for given conditions. For the pressure drop, the results show that the pressure drop of nanofluid is slightly higher than water and increases with increase of volume concentrations. In addition, the reduction of wall temperature and heat transfer area is estimated.

  5. 2D double-layer-tube-shaped structure Bi{sub 2}S{sub 3}/ZnS heterojunction with enhanced photocatalytic activities

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Xiaoming, E-mail: dawn1026@163.com [Department of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yan' an University, Yanan, Shaanxi 716000 (China); Wang, Zihang; Fu, Feng [Department of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yan' an University, Yanan, Shaanxi 716000 (China); Li, Xiang [Department of Chemistry and Chemical Engineering, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yan' an University, Yanan, Shaanxi 716000 (China); Department of Chemical Engineering, Northwest University, Xian, Shaanxi 710069 (China); Li, Wenhong [Department of Chemical Engineering, Northwest University, Xian, Shaanxi 710069 (China)

    2015-10-01

    Bi{sub 2}S{sub 3}/ZnS heterojunction with 2D double-layer-tube-shaped structures was prepared by the facile synthesis method. The corresponding relationship was obtained among loaded content to phase, morphology, and optical absorption property of Bi{sub 2}S{sub 3}/ZnS composite. The results shown that Bi{sub 2}S{sub 3} loaded could evidently change the crystallinity of ZnS, enhance the optical absorption ability for visible light of ZnS, and improve the morphologies and microstructure of ZnS. The photocatalytic activities of the Bi{sub 2}S{sub 3}/ZnS sample were evaluated for the photodegradation of phenol and desulfurization of thiophene under visible light irradiation. The results showed that Bi{sub 2}S{sub 3} loaded greatly improved the photocatalytic activity of ZnS, and the content of loaded Bi{sub 2}S{sub 3} had an impact on the catalytic activity of ZnS. Moreover, the mechanism of enhanced photocatalytic activity was also investigated by analysis of relative band positions of Bi{sub 2}S{sub 3} and ZnS, and photo-generated hole was main active radicals during photocatalytic oxidation process.

  6. Wound tube heat exchanger

    Science.gov (United States)

    Ecker, Amir L.

    1983-01-01

    What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

  7. A comparison of the McGrath® Series 5 videolaryngoscope and Macintosh laryngoscope for double-lumen tracheal tube placement in patients with a good glottic view at direct laryngoscopy.

    Science.gov (United States)

    Yao, W L; Wan, L; Xu, H; Qian, W; Wang, X R; Tian, Y K; Zhang, C H

    2015-07-01

    We compared the McGrath® Series 5 videolaryngoscope with the Macintosh laryngoscope for double-lumen tracheal tube placement in patients with a predicted good glottic view on assessment of the airway. An initial laryngoscopy was performed using the Macintosh laryngoscope; 96 patients with Cormack and Lehane grade-1 or -2a views were randomly assigned to undergo intubation using either the McGrath or Macintosh device. Compared with the Macintosh laryngoscope, the McGrath videolaryngoscope provided more Cormack and Lehane grade-1 views (47 (97.9%) vs 29 (60.4%), p Cormack and Lehane grade ≥ 2b on initial laryngoscopy using the Macintosh, the glottic view was improved on intubation with the McGrath videolaryngoscope, with a total success rate of double-lumen tube placement of 94.4% and mean (SD) intubation time of 50.0 (18.6) s. We recommend that in patients with a low airway risk index score requiring intubation with a double-lumen tracheal tube, the Macintosh laryngoscope is used as the first device and the McGrath videolaryngoscope is used only if this provides a poor glottic view. © 2015 The Association of Anaesthetists of Great Britain and Ireland.

  8. Difficulty in inserting left double-lumen endobronchial tubes at the cricoid level in small-statured women: A retrospective study

    Directory of Open Access Journals (Sweden)

    Mika Sato

    2017-01-01

    Full Text Available Background and Aims: Left double-lumen endobronchial tube (DLT sizes are selected using tracheal diameters and left mainstem bronchial diameters (LMBDs determined from chest radiographs or computed tomography (CT scans. In Western women, 35-Fr or 37-Fr DLTs are often selected. However, difficulties can be encountered when inserting 32-Fr or 35-Fr DLTs in Japanese women. We investigated success rates for 32-Fr or 35-Fr DLT insertion in Japanese women and determined the causes of unsuccessful DLT insertion. Methods: We searched anaesthesia records of Japanese women aged ≥20 years who underwent thoracic surgery with 32-Fr or 35-Fr DLTs between April 2010 and March 2015 in our hospital. In the successful group (SG, patients were intubated using the initially selected DLTs. By contrast, in the unsuccessful group (UG, the DLT size had to be changed. The Mann–Whitney U-test and Fisher's exact test were used to compare groups. Results: The SG included 149 (96.1% of 155 cases of 32-Fr DLT use and 119 (95.2% of 125 cases of 35-Fr DLT use. Patient height was significantly lower in the UG than in the SG for the 35-Fr DLT (P = 0.0036. In seven of 12 UG patients (three for 32-Fr and four for 35-Fr, the transverse diameters of cricoid cartilages were smaller than the DLTs' tracheal diameters, thereby preventing passage through the cricoid cartilages. Conclusion: Along with LMBDs, transverse diameters of cricoid cartilages based on CT scans or ultrasonogram findings may help in selecting the appropriate left DLT size.

  9. Disconnection technique with a bronchial blocker for improving lung deflation: a comparison with a double-lumen tube and bronchial blocker without disconnection.

    Science.gov (United States)

    Yoo, Ji Young; Kim, Dae Hee; Choi, Ho; Kim, Kun; Chae, Yun Jeong; Park, Sung Yong

    2014-08-01

    One-lung ventilation (OLV) is accomplished with a double-lumen tube (DLT) or a bronchial blocker (BB). The authors compared the effectiveness of lung collapse using DLT, BB, and BB with the disconnection technique. Prospective, randomized, blind trial. A university hospital. Fifty-two patients undergoing elective pneumothorax surgery. Patients were assigned randomly to 1 of 3 groups: The DLT group (group 1), the BB group (group 2), and the BB with the disconnection technique group (group 3). The authors modified the disconnection technique in group 3 as follows: (1) turned off the ventilator and opened the adjustable pressure-limiting valve, allowing both lungs to collapse and (2) after loss of the CO2 trace on the capnograph, inflated the blocker cuff and turned on the ventilator, allowing only dependent-lung ventilation. Five and ten minutes after OLV, the degree of lung collapse was assessed by the surgeon, who was blinded to the isolation technique. The quality of lung collapse at 5 and 10 minutes was significantly better in groups 1 and 3 than in group 2. No significant differences were observed for the degree of lung collapse at any time point between groups 1 and 3. The average time for loss of the CO2 trace on the capnograph was 32.3±7.0 seconds in group 3. A BB with spontaneous collapse took longer to deflate and did not provide equivalent surgical exposure to the DLT. The disconnection technique could be helpful to accelerate lung collapse with a BB. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Double-modification of lectin using two distinct chemistries for fluorescent ratiometric sensing and imaging saccharides in test tube or in cell.

    Science.gov (United States)

    Nakata, Eiji; Koshi, Yoichiro; Koga, Erina; Katayama, Yoshiki; Hamachi, Itaru

    2005-09-28

    The site-selective incorporation of two different fluorophores into a naturally occurring protein (lectin, a sugar-binding protein) has been successfully carried out using two distinct orthogonal chemical methods. By post-photoaffinity labeling modification, Con A, a glucose- and mannose-selective lectin, was modified with fluorescein in the proximity of the sugar binding site (Tyr100 site), and the controlled acylation reaction provided the site-selective attachment of coumarin at Lys114. In this doubly modified Con A, the fluorescein emission changed upon the binding to the corresponding sugars, such as the glucose or mannose derivatives, whereas the coumarin emission was constant. Thus, the doubly modified Con A fluorescently sensed the glucose- and mannose-rich saccharides in a ratiometric manner while retaining the natural binding selectivity and affinity, regardless of the double modification. On the benefit of the ratiometric fluorescent analysis using two distinct probes, the sugar trimming process of a glycoprotein can be precisely monitored by the engineered Con A. Furthermore, the doubly modified Con A can be used not only for the convenient fluorescent imaging of saccharides localized on a cell surface, such as the MCF-7, a breast cancer cell having rich high-mannose branch, but also for the ratiometric fluorescent sensing of the glucose concentration inside HepG2 cells. These results demonstrated that the semisynthetic lectin modified doubly by two distinct chemistries is superior to the singly modified one in function, and thus, it may be potentially useful in cell, as well as in test tube.

  11. Verminderung des Personalbedarfs durch den Einsatz einer computerbasierten Histologieprüfung [Reduction of the need for personel with a computer-based histology examination

    Directory of Open Access Journals (Sweden)

    Woermann, Ulrich

    2006-08-01

    Histologieprüfung insgesamt benötigten Personentage von 21 auf 6 zu reduzieren. Der materielle Aufwand ist mit 2 Prüfungs-PCs und einem Server-PC bescheiden. Sicherheitsprobleme bestehen bei einem in sich geschlossenen lokalen Netzwerk nicht. Durch kontinuierliche Speicherung der Prüfungsdaten auf dem Server wird ein Datenverlust vorgebeugt. Psychometrisch war die computerbasierte Histologieprüfung gleichwertig zur früher benutzten mündlich-strukturierten Prüfung. Der Einsatz von Computern kann den hohen Ressourcenbedarf von OSCE bzw. OSPE vermindern. Er kann somit mithelfen, dass ein wertvolles Prüfungsverfahren nicht an der beschränkten Verfügbarkeit von Personl scheitert.

  12. Multi-anode wire straw tube tracker

    International Nuclear Information System (INIS)

    Oh, S.H.; Ebenstein, W.L.; Wang, C.W.

    2011-01-01

    We report on a test of a straw tube detector design having several anode (sense) wires inside a straw tube. The anode wires form a circle inside the tube and are read out independently. This design could solve several shortcomings of the traditional single wire straw tube design such as double hit capability and stereo configuration.

  13. Bronchial blocker versus left double-lumen endotracheal tube in video-assisted thoracoscopic surgery: a randomized-controlled trial examining time and quality of lung deflation.

    Science.gov (United States)

    Bussières, Jean S; Somma, Jacques; Del Castillo, José Luis Carrasco; Lemieux, Jérôme; Conti, Massimo; Ugalde, Paula A; Gagné, Nathalie; Lacasse, Yves

    2016-07-01

    Double-lumen endotracheal tubes (DL-ETT) and bronchial blockers (BB) have both been used for lung isolation in video-assisted thoracic surgery (VATS). Though not well studied, it is widely thought that a DL-ETT provides faster and better quality lung collapse. The aim of this study was to compare a BB technique vs a left-sided DL-ETT strategy with regard to the time and quality of lung collapse during one-lung ventilation (OLV) for elective VATS. Forty patients requiring OLV for VATS were randomized to receive a BB (n = 20) or a left-sided DL-ETT (n = 20). The primary endpoint was the time from pleural opening (performed by the surgeon) until complete lung collapse. The time was evaluated offline by reviewing video recorded during the VATS. The quality of lung deflation was also graded offline using a visual scale (1 = no lung collapse; 2 = partial lung collapse; and 3 = total lung collapse) and was recorded at several time points after pleural incision. The surgeon also graded the time to complete lung collapse and quality of lung deflation during the procedure. The surgeon's guess as to which device was used for lung isolation was also recorded. Of the 40 patients enrolled in the study, 20 patients in the DL-ETT group and 18 in the BB group were analyzed. There mean (standard deviation) time to complete lung collapse of the operative lung was significantly faster using the BB compared with using the DL-ETT [7.5 (3.8) min vs 36.6 (29.1) min, respectively; mean difference, 29.1 min; 95% confidence interval, 1.8 to 7.2; P < 0.001]. Overall, a higher proportion of patients in the BB group than in the DL-ETT group achieved a quality of lung collapse score of 3 at five minutes (57% vs 6%, respectively; P < 0.004), ten minutes (73% vs 14%, respectively; P = 0.005), and 20 min (100% vs 25%, respectively; P = 0.002) after opening the pleura. The surgeon incorrectly guessed the type of device used in 78% of the BB group and 50% of the DL-ETT group (P = 0.10). The time and

  14. Influence of double hydrogen bonds and alkyl chains on the gelation of nonchiral polyurethane model compounds: sheets, eaves trough, tubes and oriented fibers.

    Science.gov (United States)

    Khanna, Shalini; Khan, Mostofa Kamal; Sundararajan, Pudupadi

    2009-11-17

    We describe the gelation, upon self-assembly of a series of nonchiral molecules, resulting in tubular morphology of the fibers. These are biscarbamates, which are model compounds for polyurethanes with two hydrogen bonding groups separated by a (CH(2))(6) spacer and symmetrically substituted with alkyl chains on either side varying in length from C(6) to C(18). Upon gelation, these molecules form a sheet initially. The sheets then tend to wrap, leading to tubules. Those with partial wrapping resemble eaves troughs. With the predominant growth along the hydrogen bonding direction, the energy of interaction between the molecules along this direction would be more dominant than just the van der Waals interaction in the other two, leading to asymmetry of interaction in the sheet. We rationalize such tube formation in this case on the basis of the theories [Schnur, J. M.; Ratna, B. R.; Selinger, J. V.; Singh, A.; Jyothi, G.; Easwaran, K. R. K. Science, 1994, 264, 945. Schnur, J. M. Science, 1993, 262, 166. McKierman, R. L.; Heintz, A. M.; Hsu, S. L.; Gido, S. P.; Penelle, J. Polym. Mater. Sci. Eng. 2001, 84, 416.] which were developed for amphiphilic mono and bilayers, which state that these bilayers are not at their minimal energy when they are flat, and prefer a bent state. The gelation behavior of this series with double hydrogen bond is compared with the monocarbamates with a single hydrogen bonding motif [Moniruzzaman, M.; Sundararajan, P. R. Langmuir 2005, 21, 3802.]. We attribute the tendency toward both gelation and crystallization in some cases to the competing contributions of the hydrogen bond and van der Waals interactions between the long alkyl side chains. Oriented fibers for X-ray diffraction were obtained by simply using a magnetic stir bar during gelation. It is also found that the solvents that gel with diureas [van Esch, J.; Kellogg, R. M.; Feringa, B. L. Tetrahedron Lett. 1997, 38, 281] also form gels with biscarbamates. While the biscarbamates with

  15. Feeding Tubes

    Science.gov (United States)

    ... the TPN. Tubes Used for Enteral Feeds NG (Nasogastric Tube) A flexible tube is placed via the nose, ... portion of the small intestine Naso – nose NG – Nasogastric Tube -ostomy – new opening Percutaneous – through the skin PEJ – ...

  16. Did low tube voltage CT combined with low contrast media burden protocols accomplish the goal of "double low" for patients? An overview of applications in vessels and abdominal parenchymal organs over the past 5 years.

    Science.gov (United States)

    Shen, Yaqi; Hu, Xuemei; Zou, Xianlun; Zhu, Di; Li, Zhen; Hu, Daoyu

    2016-09-01

    Imaging communities have already reached a consensus that the radiation dose of computed tomography (CT) should be reduced as much as reasonably achievable to lower population risks. Increasing attention is being paid to iodinated contrast media (CM) induced nephrotoxicity (CIN); a decrease in the intake of iodinated CM is required by increasingly more radiologists. Theoretically, the radiation dose varies with the tube current time and square of the tube voltage, with higher iodine contrast at low photon energies (Huda et al. [2000] Radiology, 21 7, 430-435).The use of low tube voltage is a promising strategy to reduce both the radiation dose and CM burden. The term 'double low' has been coined to describe scanning protocols that reduce radiation dose and iodine intake synchronously. These protocols are becoming increasingly popular in the clinical setting. The aim of this review was to describe all original studies using the 'double low' strategy in the last 5 years. We searched an online electronic database (PubMed) from January 2011 to December 2015 for original studies published on the relationship of low tube voltage with low radiation dose and low iodine contrast media burden in patients undergoing CT scans. Studies that failed to reduce radiation dose or iodine CM burden were excluded in this study. Thirty-seven studies aimed at reducing radiation dose using low tube voltage combined with iodine CM reduced protocols were included in this study. Most studies evaluated conditions associated with arteries. Four were cerebral and neck computed tomography angiography (CTA) studies, 15 were pulmonary CTA (pCTA) and coronary CTA (cCTA) studies, one concerned myocardial perfusion, five studies focused on the thoracic and abdominal aorta, and one investigated renal arteries. Three studies consisted of CT venography (CTV) of the pelvis and lower extremities. Six publications examined the liver, and two focused on the kidney. Overall, this review demonstrates that

  17. Building lab-scale x-ray tube based irradiators

    Science.gov (United States)

    The construction of economical x-ray tube based irradiators in a variety of configurations is described using 1000 Watt x-ray tubes. Single tube, double tube, and four tube designs are described, as well as various cabinet construction techniques. Relatively high dose rates were achieved for small s...

  18. Postoperative antibacterial prophylaxis for the prevention of infectious complications associated with tube thoracostomy in patients undergoing elective general thoracic surgery: a double-blind, placebo-controlled, randomized trial.

    Science.gov (United States)

    Oxman, David A; Issa, Nicolas C; Marty, Francisco M; Patel, Alka; Panizales, Christia Z; Johnson, Nathaniel N; Licona, J Humberto; McKenna, Shannon S; Frendl, Gyorgy; Mentzer, Steven J; Jaklitsch, Michael T; Bueno, Raphael; Colson, Yolonda; Swanson, Scott J; Sugarbaker, David J; Baden, Lindsey R

    2013-05-01

    To determine whether extended postoperative antibacterial prophylaxis for patients undergoing elective thoracic surgery with tube thoracostomy reduces the risk of infectious complications compared with preoperative prophylaxis only. Prospective, randomized, double-blind, placebo-controlled trial. Brigham and Women's Hospital, an 800-bed tertiary care teaching hospital in Boston, Massachusetts. A total of 251 adult patients undergoing elective thoracic surgery requiring tube thoracostomy between April 2008 and April 2011. Patients received preoperative antibacterial prophylaxis with cefazolin sodium (or other drug if the patient was allergic to cefazolin). Postoperatively, patients were randomly assigned (at a 1:1 ratio) using a computer-generated randomization sequence to receive extended antibacterial prophylaxis (n = 125) or placebo (n = 126) for 48 hours or until all thoracostomy tubes were removed, whichever came first. The combined occurrence of surgical site infection, empyema, pneumonia, and Clostridium difficile colitis by postoperative day 28. A total of 245 patients were included in the modified intention-to-treat analysis (121 in the intervention group and 124 in the placebo group). Thirteen patients (10.7%) in the intervention group and 8 patients (6.5%) in the placebo group had a primary end point (risk difference, -4.3% [95% CI, -11.3% to 2.7%]; P = .26). Six patients (5.0%) in the intervention group and 5 patients (4.0%) in the placebo group developed surgical site infections (risk difference, -0.93% [95% CI, -6.1% to 4.3%]; P = .77). Seven patients (5.8%) in the intervention group and 3 patients (2.4%) in the placebo group developed pneumonia (risk difference, -3.4% [95% CI, -8.3% to 1.6%]; P = .21). One patient in the intervention group developed empyema. No patients experienced C difficile colitis. Extended postoperative antibacterial prophylaxis for patients undergoing elective thoracic surgery requiring tube thoracostomy did not reduce the

  19. OSCE - praktische Tipps zur Implementierung einer klinisch-praktischen Prüfung [OSCE - hands on instructions for the implementation of an objective structured clinical examination

    Directory of Open Access Journals (Sweden)

    Nikendei, Christoph

    2006-08-01

    Full Text Available [english] Introduction: Objective structured clinical examinations (OSCEs have proved to be a reliable and valid assessment tool for basic clinical skills. In regards to the more and more practical education of medical students there is an increasing need for the implementation of OSCEs. To facilitate this implementation we would like to give a review of literature and to present our 12 station OSCE at the Medical Hospital of the University of Heidelberg. Methods: During winter term 2004 / 2005 143 medical students in thir 3rd year of training participated the OSCE. For the conception of the assessment a blueprint was used. Standard setting was carried out with a modified Angoff method, students performance was assessed by experts using self-developed checklists. Results: The OSCE at the Medical Hospital of the University of Heidelberg showed a reliability of 0,748. According to the results of the standard setting procedure 142 students (99,3% passed the exam. Taking the OSCE on the first, second or third day of assessment did not have impact on students' performance. Discussion: The OSCE at the Medical Hospital of the University of Heidelberg proves to be a reliable and fair assessment tool. Even the OSCE represents an assessment tool that needs resources and time it is well accepted in students and raters if it is planned and organised carefully. [german] Einleitung: Der OSCE (objective structured clinical examination hat sich als reliables und valides Instrument zur Prüfung klinisch-praktischer Fertigkeiten erwiesen. In Hinblick auf die vermehrt praxisnahe Ausbildung im Medizinstudium wächst die Notwendigkeit der Durchführung einer solchen klinisch-praktischen Prüfung. Um eine Implementierung zu erleichtern wird nach einem Literaturüberblick der 12-Stationen-OSCE an der Medizinischen Universitätsklinik Heidelberg in Hinblick auf Konzeption, Bestimmung der Bestehensgrenze, Durchführung und Notenvergabe vorgestellt. Methode: Im WS 2004

  20. FUNDAMENTAL AREAS OF PHENOMENOLOGY (INCLUDING APPLICATIONS): Linear Analysis of Folded Double-Ridged Waveguide Slow-Wave Structure for Millimeter Wave Traveling Wave Tube

    Science.gov (United States)

    He, Jun; Wei, Yan-Yu; Gong, Yu-Bin; Wang, Wen-Xiang

    2009-11-01

    A novel slow-wave structure (SWS), the folded double-ridged waveguide structure, is presented and its linear gain properties are investigated. The perturbed dispersion equation is derived and the small signal growth rate is calculated for dimensions of the ridge-loaded region and the parameters of the electron beam. The novel structure has potential applications in the production of high power and broad band radiation. For a cold beam, the linear theory predicts a gain of 1.1-1.27 dB/period and a 3-dB small-signal gain bandwidth of 30% in W-band. A comparison between the folded double-ridged waveguide SWS and folded waveguide SWS (FWSWS) shows that with the same physical parameters, the novel SWS has an advantage over the FWSWS on the bandwidth and electron efficiency.

  1. Successful 1:1 proportion ventilation with a unique device for independent lung ventilation using a double-lumen tube without complications in the supine and lateral decubitus positions. A pilot study.

    Directory of Open Access Journals (Sweden)

    Michał Kowalczyk

    Full Text Available Adequate blood oxygenation and ventilation/perfusion matching should be main goal of anaesthetic and intensive care management. At present, one of the methods of improving gas exchange restricted by ventilation/perfusion mismatching is independent ventilation with two ventilators. Recently, however, a unique device has been developed, enabling ventilation of independent lungs in 1:1, 2:1, 3:1, and 5:1 proportions. The main goal of the study was to evaluate the device's utility, precision and impact on pulmonary mechanics. Secondly- to measure the gas distribution in supine and lateral decubitus position.69 patients who underwent elective thoracic surgery were eligible for the study. During general anaesthesia, after double lumen tube intubation, the aforementioned control system was placed between the anaesthetic machine and the patient. In the supine and lateral decubitus (left/right positions, measurements of conventional and independent (1:1 proportion ventilation were performed separately for each lung, including the following: tidal volume, peak pressure and dynamic compliance.Our results show that conventional ventilation using Robertshaw tube in the supine position directs 47% of the tidal volume to the left lung and 53% to the right lung. Furthermore, in the left lateral position, 44% is directed to the dependent lung and 56% to the non-dependent lung. In the right lateral position, 49% is directed to the dependent lung and 51% to the non-dependent lung. The control system positively affected non-dependent and dependent lung ventilation by delivering equal tidal volumes into both lungs with no adverse effects, regardless of patient's position.We report that gas distribution is uneven during conventional ventilation using Robertshaw tube in the supine and lateral decubitus positions. However, this recently released control system enables precise and safe independent ventilation in the supine and the left and right lateral decubitus

  2. DEVELOPMENT OF AN ANALYTICAL METHOD TO EVALUATE THE INTEGRITY OF A CALANDRIA TUBE IN THE CASE OF PRESSURE TUBE RUPTURE

    OpenAIRE

    森下 善嗣

    1990-01-01

    An analytical method which consists of two‐dimensional thermal‐hydraulic analysis and three‐dimensional structural analysis has been proposed to evaluate the integrity of a calandria tube in the case of pressure tube rupture in a pressure tube type reactor.In order to validate the method,experiments were carried out with coaxially arranged double tubes simulating a pressure tube and a calandria tube.Experimental data were also comparedwith analytical results with the proposed method.

  3. Alterações oculares em micose fungóide associada com vírus linfotrópico de células t humanas tipo I

    OpenAIRE

    Mendes Junior,Epaminondas de Souza; Guerra,Ricardo Luz Leitão; Palma,Leonora Cristina Leal; Marback,Eduardo Ferrari; Marback,Patrícia Maria Fernandes

    2010-01-01

    São relatados dois casos da associação de micose fungóide e HTLV-I. Os achados oftalmológicos observados foram, no caso 1: ceratopatia ponteada e ceratoconjuntivite seca e; no caso 2: ceratoconjuntivite seca, espessamento e nódulos difusos em bordas palpebrais. A associação de micose fungóide e HTLV-I nos dois casos sugere envolvimento deste vírus na etiopatogenia da doença. Maior conhecimento e realização de estudos bem controlados poderão ser úteis na determinação precisa desta hipótese....

  4. Micose fungóide hipopigmentar com 20 anos de evolução Hypopigmented mycosis fungoides with 20 years evolution

    Directory of Open Access Journals (Sweden)

    Rodrigo Pereira Duquia

    2005-04-01

    Full Text Available A micose fungóide hipopigmentar é uma forma rara de linfoma cutâneo de células T, em que lesões hipopigmentadas ocorrem na ausência de lesões clássicas dessa neoplasia. Na literatura latino-americana existem apenas três casos; relata-se aqui o caso de um homem negro, de 29 anos com lesões há 20 anos O tratamento é semelhante ao de outros tipos de linfomas T cutâneos, sendo o psoraleno mais ultravioleta A (Puva e a mostarda nitrogenada tópica os mais relatados.Hypopigmented mycosis fungoides is a rare variant of the cutaneous T-cell lymphoma, in which hypopigmented lesions are seen without the classical lesions. Only three cases are found in the Latin-American literature. We report the case of a 29-year-old black male patient, who first presented with these lesions 20 years ago. The treatment is similar to the classical forms of the disease: psoralen plus ultraviolet A (PUVA and topical nitrogen mustard are most often used.

  5. Measurement of the delta34S value in methionine by double spike multi-collector thermal ionization mass spectrometry using Carius tube digestion.

    Science.gov (United States)

    Mann, Jacqueline L; Kelly, W Robert

    2010-09-15

    Methionine is an essential amino acid and is the primary source of sulfur for humans. Using the double spike ((33)S-(36)S) multi-collector thermal ionization mass spectrometry (MC-TIMS) technique, three sample bottles of a methionine material obtained from the Institute for Reference Materials and Measurements have been measured for delta(34)S and sulfur concentration. The mean delta(34)S value, relative to Vienna Canyon Diablo Troilite (VCDT), determined was 10.34 +/- 0.11 per thousand (n = 9) with the uncertainty reported as expanded uncertainties (U). These delta(34)S measurements include a correction for blank which has been previously ignored in studies of sulfur isotopic composition. The sulfur concentrations for the three bottles range from 56 to 88 microg/g. The isotope composition and concentration results demonstrate the high accuracy and precision of the DS-MC-TIMS technique for measuring sulfur in methionine.

  6. A Fatal Aortoesophageal Fistula Caused by Critical Combination of Double Aortic Arch and Nasogastric Tube Insertion for Superior Mesenteric Artery Syndrome

    Directory of Open Access Journals (Sweden)

    Tomofumi Miura

    2010-06-01

    Full Text Available Double aortic arch (DAA is a rare vascular congenital abnormality. Since a vascular ring surrounds bronchus and esophagus, any oral or nasal intubation can physically cause fatal aortoesophageal fistula (AEF. We report herein the first case of association of DAA and superior mesenteric artery (SMA syndrome and the second case of AEF caused by nasogastric intubation in an adult with DAA. A 19-year-old woman visited our hospital for nausea and vomiting. She was diagnosed with SMA syndrome by computed tomography (CT. Nasogastric intubation relieved her symptoms in 4 days. Extramural compression with top ulceration was found in esophagogastroduodenoscopy on the 5th hospital day. She suddenly showed massive hematemesis on the 12th hospital day. AEF was found by CT. Soon, she died despite of intensive care. Retrospective interview disclosed the fact that DAA was pointed out in her childhood. We conclude that intubation must be avoided in DAA and a detailed clinical interview about DAA is mandatory to avoid AEF.

  7. Geotextile Tube Structures Guidelines for Contract Specifications

    Science.gov (United States)

    2006-09-01

    Nonwoven fabrics: Diaphragm Bursting Strength Tester Method ASTM D 3884 (1992) Abrasion Resistance of Textile Fabrics (Rotary Platform, Double-Head... filter cloth, excavation of borrow material, transportation of borrow material, filling of the tubes, coating of the completed tubes, disposal of waste

  8. Ear Tubes

    Science.gov (United States)

    ... of the ear drum or eustachian tube, Down Syndrome, cleft palate, and barotrauma (injury to the middle ear caused by a reduction of air pressure, ... specialist) may be warranted if you or your child has experienced repeated ... fluid in the middle ear, barotrauma, or have an anatomic abnormality that ...

  9. The Mashups of YouTube

    DEFF Research Database (Denmark)

    Simonsen, Thomas Mosebo

    2013-01-01

    , but rather in its social and communicative abilities within the YouTube community. This leads to the article’s overall argument that the main characteristic of the YouTube Mashup can be explained in terms of connectivity. It is argued that Mashups reveal a double articulation of connectivity; one......This article focuses on YouTube mashups and how we can understand them as a specific subgenre on YouTube. The Mashups are analysed as audiovisual recontextualizations that are given new meaning, e.g., via collaborative social communities or for individual promotional purposes. This is elaborated...... that involves the social mechanisms of the Mashups, and another mode, which concerns the explicit embedding of structural connectivity that accentuates the medium-specific infrastructure of YouTube. This double articulation of connectivity is furthermore elaborated on by including Grusin and Bolter’s concept...

  10. Neutron tubes

    Science.gov (United States)

    Leung, Ka-Ngo [Hercules, CA; Lou, Tak Pui [Berkeley, CA; Reijonen, Jani [Oakland, CA

    2008-03-11

    A neutron tube or generator is based on a RF driven plasma ion source having a quartz or other chamber surrounded by an external RF antenna. A deuterium or mixed deuterium/tritium (or even just a tritium) plasma is generated in the chamber and D or D/T (or T) ions are extracted from the plasma. A neutron generating target is positioned so that the ion beam is incident thereon and loads the target. Incident ions cause D-D or D-T (or T-T) reactions which generate neutrons. Various embodiments differ primarily in size of the chamber and position and shape of the neutron generating target. Some neutron generators are small enough for implantation in the body. The target may be at the end of a catheter-like drift tube. The target may have a tapered or conical surface to increase target surface area.

  11. Design for Double Rainbow

    Science.gov (United States)

    Thomas, Lisa Carlucci

    2011-01-01

    Rare is the inspirational, spontaneous, transformative moment shared among 20 million people. In the summer of 2010, people around the world were moved by the sighting of a double rainbow--almost a triple rainbow--"all the way across the sky" in Yosemite National Park. Caught on video and posted to by YouTube by Paul Vasquez in January 2010, the…

  12. photomultiplier tubes

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  13. photomultiplier tube

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  14. Micose fungóide: estudo epidemiológico de 17 casos e avaliação da resposta terapêutica à PUVA Mycosis fungoides: epidemiologic study of 17 cases and evaluation of PUVA photochemotherapy

    Directory of Open Access Journals (Sweden)

    Ida Duarte

    2006-02-01

    Full Text Available FUNDAMENTOS: A fotoquimioterapia com PUVA é indicada para tratamento da micose fungóide, empregada como monoterapia em estágios precoces ou combinada a outras drogas nos estágios mais avançados da doença. OBJETIVOS: Avaliação da resposta terapêutica à fotoquimioterapia PUVA em pacientes com micose fungóide. MÉTODOS: Entre janeiro de 1996 e novembro de 2003 avaliaram-se 17 pacientes com micose fungóide no setor de Fototerapia da Clínica Dermatológica da Santa Casa de São Paulo. A terapia com PUVA foi realizada como monoterapia nos estádios iniciais ou como coadjuvante nos estádios avançados da doença. Avaliou-se o resultado do tratamento quanto ao aspecto clínico das lesões e parâmetros histológicos após tratamento. RESULTADOS: Quatorze de 16 pacientes responderam à fotoquimioterapia. Relacionando o estadiamento da doença à resposta terapêutica obteve-se o seguinte: cinco pacientes (um em estágio IA e quatro em IB com controle total (cura das lesões; quatro (todos IB com melhora intensa (controle de 70-99%; dois (IIB e IVA com melhora moderada (de 50 a 69%; três (IA, IB, IIA com melhora discreta (menos 50%; dois (IB, IIB inalterados (sem resposta. Um paciente teve de descontinuar o tratamento por apresentar intenso ardor. CONCLUSÃO: Houve resposta à terapia PUVA em 87% dos pacientes, com controle total ou melhora intensa da doença em 56% dos casos. Sua efetividade permitiu regressão das lesões cutâneas, principalmente nos casos precoces. A fotoquimioterapia com PUVA mostrou ser tratamento seguro e efetivo, devendo ser considerado em pacientes com micose fungóide.BACKGROUND: PUVA photochemotherapy is indicated to treat mycosis fungoides, either as monotherapy in the earlier stages of the disease or in combination with other drugs in more advanced stages of evolution. OBJECTIVES: To evaluate PUVA photochemotherapy response in patients with mycosis fungoides. METHODS: From January 1996 to November 2003, 17

  15. Tracheostomy tube - eating

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000464.htm Tracheostomy tube - eating To use the sharing features on ... when you swallow foods or liquids. Eating and Tracheostomy Tubes When you get your tracheostomy tube, or ...

  16. Eustachian tube patency

    Science.gov (United States)

    Eustachian tube patency refers to how much the eustachian tube is open. The eustachian tube runs between the middle ear and the throat. It controls the pressure behind the eardrum and middle ear space. This helps keep ...

  17. Heat exchanger tube mounts

    Science.gov (United States)

    Wolowodiuk, W.; Anelli, J.; Dawson, B.E.

    1974-01-01

    A heat exchanger in which tubes are secured to a tube sheet by internal bore welding is described. The tubes may be moved into place in preparation for welding with comparatively little trouble. A number of segmented tube support plates are provided which allow a considerable portion of each of the tubes to be moved laterally after the end thereof has been positioned in preparation for internal bore welding to the tube sheet. (auth)

  18. Tube holding system

    International Nuclear Information System (INIS)

    Cunningham, R.C.

    1978-01-01

    A tube holding rig is described for the lateral support of tubes arranged in tight parcels in a heat exchanger. This tube holding rig includes not less than two tube supporting assemblies, with a space between them, located crosswise with respect to the tubes, each supporting assembly comprising a first set of parallel components in contact with the tubes, whilst a second set of components is also in contact with the tubes. These two sets of parts together define apertures through which the tubes pass [fr

  19. Tracheostomy tube - speaking

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000465.htm Tracheostomy tube - speaking To use the sharing features on ... are even speaking devices that can help you. Tracheostomy Tubes and Speaking Air passing through vocal cords ( ...

  20. X-ray tubes

    International Nuclear Information System (INIS)

    Young, R.W.

    1979-01-01

    A form of x-ray tube is described which provides satisfactory focussing of the electron beam when the beam extends for several feet from gun to target. Such a tube can be used for computerised tomographic scanning. (UK)

  1. Neural Tube Defects

    Science.gov (United States)

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the ... that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In ...

  2. Jejunostomy feeding tube

    Science.gov (United States)

    ... may replace the tube every now and then. Cleaning the Skin Around the J-tube To clean ... this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial ...

  3. One lung Isolation using a Nasogastric tube and Foley's catheter: A ...

    African Journals Online (AJOL)

    Pneumonectomy for suppurative lung disease requires that one-lung anaesthesia be employed to protect the healthy lung from soilage by the diseased lung. The most commonly used technique for achieving lung isolation involves the use of a double lumen tube. However, the use of a double lumen tube especially in ...

  4. Mycosis fungoides and Sézary syndrome: clinical, histopathological and immunohistochemical review and update Micose fungóide e síndrome de Sézary: revisão e atualização clínica, histopatológica e imuno-histoquímica

    Directory of Open Access Journals (Sweden)

    Thamy Yamashita

    2012-12-01

    Full Text Available This paper reviews the diagnostic and classificatory concepts of mycosis fungoides and Sézary syndrome in light of the latest normative publications. It describes the great variability of the clinical expression of mycosis fungoides in its early stages as well as the histopathological and immunohistochemical aspects that help with diagnosis. The diagnostic criteria required for characterizing Sézary syndrome and the staging system used for both mycosis fungoides and Sézary syndrome are described.O artigo revisa os conceitos diagnósticos e de classificação da micose fungóide e da síndrome de Sézary a luz das publicações normativas mais recentes. Descreve a grande variabilidade de expressão clinica da micose fungóide em seus estágios iniciais assim como os aspectos histopatológicos e imuno-histoquímicos auxiliares ao diagnóstico. São descritos os critérios de diagnósticos exigidos para que se caracterize a síndrome de Sézary e o sistema de estadiamento, utilizado para ambas, micose fungóide e síndrome de Sézary.

  5. Nasogastric and feeding tubes.

    Science.gov (United States)

    Gharib, Ahmed M; Stern, Eric J; Sherbin, Vandy L; Rohrmann, Charles A

    1996-05-01

    Preview The authors' experience in a radiology department suggested to them that there is a wide range of beliefs among practitioners regarding proper placement of nasogastric and feeding tubes. Improper positioning can cause serious problems, as they explain. Indications for different tube positions, complications of incorrect tube placement, and directions for proper positioning are discussed and illustrated.

  6. Construction of preheaters with horizontal tubes

    Energy Technology Data Exchange (ETDEWEB)

    Goetze

    1944-09-27

    This report involved construction of preheaters for distillation and cracking plants in the oil industry, particularly in America. The use of heat transmission by radiation was also a consideration here. The recycling of waste gases occurred, but was not the rule. A convection section was often built next to the radiation section, in which the discharge gases were used for heating the incoming product. The general arrangement of the preheaters was discussed. The first form was a rectangular box with fireproof lining with tubes arranged in a single row along the outer walls and sometimes in a double row on the ceiling. It consisted of smooth and finned tubes. From the simple form a double preheater was developed that allowed one or two common discharge flues to provide as large a heating surface as possible within a reasonable space. Other items discussed were recycling of waste gases, reasons for the choice of horizontal preheaters with radiation heating, the use of vertical tubes in the U.S.A. and elsewhere in the oil industry, details of horizontal preheater tubes, end closures, material, suspension, protection against overloading by radiation, circulation heating, burners, use of horizontal radiation preheaters in hydrogenation in the U.S.A., rebuilding I. G. preheaters, construction, tube supports, and masonry. A list of references on cracking, preheaters, heat transmission, and alloyed steels was given.

  7. 21 CFR 868.5800 - Tracheostomy tube and tube cuff.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tracheostomy tube and tube cuff. 868.5800 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5800 Tracheostomy tube and tube cuff. (a) Identification. A tracheostomy tube and tube cuff is a device intended to be placed into a...

  8. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... YouTube Videos >> NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration ... Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: ...

  9. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... YouTube Videos > NEI YouTube Videos: Amblyopia NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia ... of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: Amblyopia ...

  10. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... NEI YouTube Videos > NEI YouTube Videos: Amblyopia NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration ... Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: ...

  11. Modelling the flow and the two-phase science of heat inside a cross-section tube of a `once through` vapor generator overheated with sodium; Modelisation de l`ecoulement et de la thermique double phase a l`interieur d`un tube droit de generateur de vapeur `once-through` a surchauffe chauffe au sodium

    Energy Technology Data Exchange (ETDEWEB)

    Mutelle, H

    1997-11-28

    Concerning the future fast neutrons reactors, studied in the frame of the European Fast Reactor (E.F.R.) project, several innovations have been proposed particularly in the field of vapor generators. These vapor generators have the particularity to use two different exchange fluids which can react violently one with the other. The thermodynamic fluid or secondary fluid is water under high pressure (18.5 MPa) which comes under saturated in the inlet of the device, warms and vaporizes inside the nest of boiler-tubes. At the outlet, vapor is overheated. The primary fluid is a liquid metal (sodium for French reactors) which flows outside the nest of boiler-tubes in the opposite direction of the secondary fluid. Several vapor generators models have been carried out. Concerning the European Fast Reactor project, the tubes have a cross-section and are in ferritic steel. Inside the boiler-tubes, the water-vapor flow can be divided into three areas. The first one is the liquid monophasic rate. It ends by the start of the boiling which is nucleated in the shell. Downstream, the two-phase flow passes from a bubbles flow to an annular flow. The liquid is then on the form of shell film and on the form of droplets carried along by the vapor flux. The dryout of the annular film is the start of the third area where there is vapor forced convection. At the present time, there is still no thermohydraulic code in the conditions of the E.F.R. vapor generator. In order to have a reliable size tool, the members of the E.F.R. project have then decided to do a two-phase flow model and have experimented a mono tubular scale model called ``ATLAS`` which represents well the real component for size, fluids and running conditions. The aim of the present work is then, in the frame of this experimental program, to 1)qualify the heat exchange and friction laws which will be later introduced in the thermohydraulic codes of cross-sections vapor generators 2)characterize the dryout phenomenon 3

  12. She's the boss: signaling in pollen tube reception.

    Science.gov (United States)

    Kessler, Sharon A; Grossniklaus, Ueli

    2011-10-01

    In angiosperms, the sperm cells are carried within the pollen tubes (male gametophytes) to the female gametophyte so that double fertilization can occur. The female gametophyte exerts control over the male, with specialized cells known as synergids guiding the pollen tubes and controlling their behavior when they enter the female gametophyte so that the sperm cells can be delivered to the egg and central cell. Upon pollen tube arrival at the ovule, signal transduction cascades mediated by receptor-like kinases are initiated in both the synergid and the tip of the pollen tube, leading to synergid cell death and pollen tube rupture. In this review, we discuss the role of these receptors and of newly discovered members of the pollen tube reception pathway. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Lunar Lava Tube Sensing

    Science.gov (United States)

    York, Cheryl Lynn; Walden, Bryce; Billings, Thomas L.; Reeder, P. Douglas

    1992-01-01

    Large (greater than 300 m diameter) lava tube caverns appear to exist on the Moon and could provide substantial safety and cost benefits for lunar bases. Over 40 m of basalt and regolith constitute the lava tube roof and would protect both construction and operations. Constant temperatures of -20 C reduce thermal stress on structures and machines. Base designs need not incorporate heavy shielding, so lightweight materials can be used and construction can be expedited. Identification and characterization of lava tube caverns can be incorporated into current precursor lunar mission plans. Some searches can even be done from Earth. Specific recommendations for lunar lava tube search and exploration are (1) an Earth-based radar interferometer, (2) an Earth-penetrating radar (EPR) orbiter, (3) kinetic penetrators for lunar lava tube confirmation, (4) a 'Moon Bat' hovering rocket vehicle, and (5) the use of other proposed landers and orbiters to help find lunar lava tubes.

  14. Steam generator tube performance

    International Nuclear Information System (INIS)

    Tatone, O.S.; Pathania, R.S.

    1983-08-01

    A review of the performance of steam generator tubes in 110 water-cooled nuclear power reactors showed that tubes were plugged at 46 (42 percent) of the reactors. The number of tubes removed from service increased from 1900 (0.14 percent) in 1980 to 4692 (0.30 percent) in 1981. The leading causes of tube failures were stress corrosion cracking from the primary side, stress corrosion cracking (or intergranular attack) from the secondary side and pitting corrosion. The lowest incidence of corrosion-induced defects from the secondary side occurred in reactors that used all-volatile treatment since start-up. At one reactor a large number of degraded tubes were repaired by sleeving which is expected to become an important method of tube repair in the future

  15. Manual tube welding torch

    International Nuclear Information System (INIS)

    Kiefer, J.H.; Smith, D.J.

    1981-01-01

    In a welding torch which fits over a tube intermediate the ends thereof for welding the juncture between the tube and a boss on the back side of a tube plate, a split housing encloses a tungsten electrode, a filler wire duct and a fiber optic bundle arranged to observe the welding process. A shielding gas duct is provided in the housing. A screw is provided for setting electrode/work distance. Difficult remote tube welding operations can be performed with the apparatus. (author)

  16. Steam generator tube performance

    International Nuclear Information System (INIS)

    Tatone, O.S.; Pathania, R.S.

    1984-10-01

    A review of the performance of steam generator tubes in 116 water-cooled nuclear power reactors showed that tubes were plugged at 54 (46 percent) of the reactors. The number of tubes removed from service decreased from 4 692 (0.30 percent) in 1981 to 3 222 (0.20 percent) in 1982. The leading causes of tube failures were stress corrosion cracking from the primary side, stress corrosion cracking (or intergranular attack) from the secondary side and pitting corrosion. The lowest incidence of corrosion-induced defects from the secondary side occurred in reactors that have used only volatile treatment, with or without condensate demineralization

  17. Sapphire tube pressure vessel

    Science.gov (United States)

    Outwater, John O.

    2000-01-01

    A pressure vessel is provided for observing corrosive fluids at high temperatures and pressures. A transparent Teflon bag contains the corrosive fluid and provides an inert barrier. The Teflon bag is placed within a sapphire tube, which forms a pressure boundary. The tube is received within a pipe including a viewing window. The combination of the Teflon bag, sapphire tube and pipe provides a strong and inert pressure vessel. In an alternative embodiment, tie rods connect together compression fittings at opposite ends of the sapphire tube.

  18. Fuel nozzle tube retention

    Energy Technology Data Exchange (ETDEWEB)

    Cihlar, David William; Melton, Patrick Benedict

    2017-02-28

    A system for retaining a fuel nozzle premix tube includes a retention plate and a premix tube which extends downstream from an outlet of a premix passage defined along an aft side of a fuel plenum body. The premix tube includes an inlet end and a spring support feature which is disposed proximate to the inlet end. The premix tube extends through the retention plate. The spring retention feature is disposed between an aft side of the fuel plenum and the retention plate. The system further includes a spring which extends between the spring retention feature and the retention plate.

  19. Steam generator tube failures

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service.

  20. Steam generator tube failures

    International Nuclear Information System (INIS)

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service

  1. Chest Tube Thoracostomy

    Science.gov (United States)

    ... in the space around the lungs (called a pleural effusion) . A chest tube may also be needed when a patient has ... or chest CT are also done to evaluate pleural fluid. If the X-ray shows a need for a chest tube to drain fluid or air, the procedure is ...

  2. Double Trouble

    NARCIS (Netherlands)

    Elsaesser, Thomas; Kievit, Robert; Simons, Jan

    1994-01-01

    Double Trouble highlights the career of Dutch scriptwriter and television producer Chiem van Houweninge, well-known for his long-running TV comedy series and as author of episodes for TV detective series. Double Trouble gives Van Houweninge's own views on writing and filming in television prime

  3. Ventricular tachycardia following tube thoracotomy.

    Science.gov (United States)

    Hibbert, Benjamin; Lim, Toon Wei; Hibbert, Rebecca; Green, Martin; Gollob, Michael H; Davis, Darryl R

    2010-10-01

    Arrhythmias provoked by tube thoracotomy are a rare complication. We report a ventricular tachycardia after chest tube insertion for a device-related pneumothorax. Sinus rhythm was restored only by removal of the chest tube and insertion of a pliable pleural drain. Identification of the chest tube as an arrhythmic trigger following tube thoracotomy is essential in definitive management of refractory arrhythmias.

  4. Molybdenum Tube Characterization report

    Energy Technology Data Exchange (ETDEWEB)

    Beaux II, Miles Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Usov, Igor Olegovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-07

    Chemical vapor deposition (CVD) techniques have been utilized to produce free-standing molybdenum tubes with the end goal of nuclear fuel clad applications. In order to produce tubes with properties desirable for this application, deposition rates were lowered requiring long deposition durations on the order of 50 hours. Standard CVD methods as well as fluidized-bed CVD (FBCVD) methods were applied towards these objectives. Characterization of the tubes produced in this manner revealed material suitable for fuel clad applications, but lacking necessary uniformity across the length of the tubes. The production of freestanding Mo tubes that possess the desired properties across their entire length represents an engineering challenge that can be overcome in a next iteration of the deposition system.

  5. Categorising YouTube

    DEFF Research Database (Denmark)

    Simonsen, Thomas Mosebo

    2011-01-01

    This article provides a genre analytical approach to creating a typology of the User Generated Content (UGC) of YouTube. The article investigates the construction of navigation processes on the YouTube website. It suggests a pragmatic genre approach that is expanded through a focus on YouTube’s...... technological affordances. Through an analysis of the different pragmatic contexts of YouTube, it is argued that a taxonomic understanding of YouTube must be analysed in regards to the vacillation of a user-driven bottom-up folksonomy and a hierarchical browsing system that emphasises a culture of competition...... and which favours the already popular content of YouTube. With this taxonomic approach, the UGC videos are registered and analysed in terms of empirically based observations. The article identifies various UGC categories and their principal characteristics. Furthermore, general tendencies of the UGC within...

  6. Passive heat transfer enhancement in 3D corrugated tube

    DEFF Research Database (Denmark)

    Navickaité, Kristina; Engelbrecht, Kurt; Bahl, Christian

    2017-01-01

    An innovative hydraulic design was studied for corrugated tube geometry for a heat exchanger. An ellipse based double corrugation was used as a concept of the geometry. The hydraulic diameter (Dh) is maintained over the tube length while the shape of the cross section varies continuously along...... the flow direction. 38 corrugated tubes with a Dh of 5 mm were studied numerically with corrugation heights from 0.23 to 0.69 mm and corrugation periods from 5 to 50 mm for laminar flow with water. Computational fluid dynamics (CFD) is used as a tool to study the effect of corrugation geometry on heat...

  7. Status of pulse tube development at CEA/SBT

    International Nuclear Information System (INIS)

    Ravex, A.; Rolland, P.

    1994-01-01

    Interest in the pulse tube comes from its potential for high reliability and low level of induced vibration. A numerical model has been developed to provide a tool for practical design. It has been successfully validated against the experimental results obtained with a single stage double inlet pulse tube which has achieved a temperature of 28 K at a frequency of a few Hz. Further developments have demonstrated the capability of operating a pulse tube at higher frequencies in association with a Stirling pressure oscillator. Current projects include coaxial geometry for miniature pulse tubes with linear resonant pressure oscillators. A 4 K multistaged pulse tube is also in development. (authors). 5 figs., 12 refs

  8. Isolated Fallopian Tube Torsion

    Directory of Open Access Journals (Sweden)

    S. Kardakis

    2013-01-01

    Full Text Available Isolated torsion of the Fallopian tube is a rare gynecological cause of acute lower abdominal pain, and diagnosis is difficult. There are no pathognomonic symptoms; clinical, imaging, or laboratory findings. A preoperative ultrasound showing tubular adnexal masses of heterogeneous echogenicity with cystic component is often present. Diagnosis can rarely be made before operation, and laparoscopy is necessary to establish the diagnosis. Unfortunately, surgery often is performed too late for tube conservation. Isolated Fallopian tube torsion should be suspected in case of acute pelvic pain, and prompt intervention is necessary.

  9. Automation in tube finishing bay

    International Nuclear Information System (INIS)

    Bhatnagar, Prateek; Satyadev, B.; Raghuraman, S.; Syama Sundara Rao, B.

    1997-01-01

    Automation concept in tube finishing bay, introduced after the final pass annealing of PHWR tubes resulted in integration of number of sub-systems in synchronisation with each other to produce final cut fuel tubes of specified length, tube finish etc. The tube finishing bay which was physically segregated into four distinct areas: 1. tube spreader and stacking area, 2. I.D. sand blasting area, 3. end conditioning, wad blowing, end capping and O.D. wet grinding area, 4. tube inspection, tube cutting and stacking area has been studied

  10. X-ray tube

    International Nuclear Information System (INIS)

    Webley, R.S.

    1975-01-01

    The object of the invention described is to provide an X-ray tube providing a scanned X-ray output which does not require a scanned electron beam. This is obtained by an X-ray tube including an anode which is rotatable about an axis, and a source of a beam of energy, for example an electron beam, arranged to impinge on a surface of the anode to generate X-radiation substantially at the region of incidence on the anode surface. The anode is rotatable about the axis to move the region of incidence over the surface. The anode is so shaped that the rotation causes the region of incidence to move in a predetermined manner relative to fixed parts of the tube so that the generated X-radiation is scanned in a predetermined manner relative to the tube. (UK)

  11. Tube Alinement for Machining

    Science.gov (United States)

    Garcia, J.

    1984-01-01

    Tool with stepped shoulders alines tubes for machining in preparation for welding. Alinement with machine tool axis accurate to within 5 mils (0.13mm) and completed much faster than visual setup by machinist.

  12. Steam generator tube performance

    International Nuclear Information System (INIS)

    Tatone, O.S.; Pathania, R.S.

    1982-04-01

    The performance of steam generator tubes in water-cooled nuclear power reactors has been reviewed for 1980. Tube defects occurred at 38% of the 97 reactors surveyed. This is a marginal improvement over 1979 when defects occurred at 41% of the reactors. The number of failed tubes was also lower, 0.14% of the tubes in service in 1980 compared with 0.20% of those in service in 1979. Analysis of the causes of these failures indicates that stress corrosion cracking was the leading failure mechanism. Reactors that used all-volatile treatment of secondary water, with or without full-flow condensate demineralization since start-up showed the lowest incidence of corrosion-related defects

  13. Ear tube insertion

    Science.gov (United States)

    ... mastoiditis) or the brain, or that damages nearby nerves Injury to the ear after sudden changes in ... does not heal after the tube falls out. Most of the time, these problems DO NOT last long. They also ...

  14. Tube Feeding Troubleshooting Guide

    Science.gov (United States)

    ... the diameter is measured in units known as French sizes, or “Fr”; a low profile tube also ... your quality of life. You are encouraged to speak with your physician, dietitian, home care company, or ...

  15. Longitudinally excited CO2 laser with multiple laser tubes

    Science.gov (United States)

    Uno, Kazuyuki; Akitsu, Tetsuya; Jitsuno, Takahisa

    2016-11-01

    We developed a longitudinally excited CO2 laser system that was constituted of two or three laser tubes and a single driving circuit. The multiple laser tubes simultaneously produced almost the same short laser pulses with a spike pulse width of about 164 ns and a pulse tail length of about 74 μs with a single driving circuit. The double-tube system was constituted of two 30 cm-long laser tubes with inner diameters of 13 mm and 16 mm and a single driving circuit with an input energy of 2.18 J. The output energy of the 13 mm-tube was 23.3 mJ, and that of the 16 mm-tube was 21.9 mJ at a gas pressure of 4.2 kPa (CO2:N2:He = 1:1:2). The triple-tube system was constituted of three 30 cm-long laser tubes with inner diameters of 9 mm, 13 mm, and 16 mm and a single driving circuit with an input energy of 2.18 J. The output energy of the 9 mm tube was 15.9 mJ, that of the 13 mm tube was 24.1 mJ, and that of the 16 mm tube was 19.2 mJ at a gas pressure of 4.2 kPa. With the same driving circuit and the same input energy, the total output energies of the multitube laser systems were higher than the output energy of a single-tube system.

  16. Magnesium tube hydroforming

    Energy Technology Data Exchange (ETDEWEB)

    Liewald, M.; Pop, R. [Institute for Metal Forming Technology (IFU), Stuttgart (Germany)

    2008-04-15

    Magnesium alloys reveal a good strength-to-weight ratio in the family of lightweight metals and gains potential to provide up to 30% mass savings compared to aluminium and up to 75 % compared to steel. The use of sheet magnesium alloys for auto body applications is however limited due to the relatively low formability at room temperature. Within the scope of this paper, extruded magnesium tubes, which are suitable for hydroforming applications, have been investigated. Results obtained at room temperature using magnesium AZ31 tubes show that circumferential strains are limited to a maximal value of 4%. In order to examine the influence of the forming temperature on tube formability, investigations have been carried out with a new die set for hot internal high pressure (IHP) forming at temperatures up to 400 C. Earlier investigations with magnesium AZ31 tubes have shown that fractures occur along the welding line at tubes extruded over a spider die, whereby a non-uniform expansion at bursting with an elongation value of 24% can be observed. A maximum circumferential strain of approx. 60% could be attained when seamless, mechanically pre-expanded and annealed tubes of the same alloy have been used. The effect of annealing time on materials forming properties shows a fine grained structure for sufficient annealing times as well as deterioration with a large increase at same time. Hence, seamless ZM21 tubes have been used in the current investigations. With these tubes, an increased tensile fracture strain of 116% at 350 C is observed as against 19% at 20 C, obtained by tensile testing of milled specimens from the extruded tubes. This behaviour is also seen under the condition of tool contact during the IHP forming process. To determine the maximum circumferential strain at different forming temperatures and strain rates, the tubes are initially bulged in a die with square cross-section under plane stress conditions. Thereafter, the tubes are calibrated by using an

  17. Crush analysis of the foam-filled bitubal circular tube under oblique impact

    Science.gov (United States)

    Djamaluddin, F.; Abdullah, S.; Arrifin, A. K.; Nopiah, Z. M.

    2018-02-01

    This paper presents crashworthiness analysis of bitubal cylindrical tubes under different impact angular. The numerical solution of double cylindrical tubes are determined by finite element analysis (FEA). Moreover, the structure was impacted by mass block as impactor respect to longitudinal direction of the tubes. The model of structure was developed by non-linear ABAQUS sofware with variations of load angle and dimensions of tube. The outcome of this study is the respons parameters such as the peak crusing force (PCF), energy absorption (EA) and specific energy absorption (SEA), thus it can be expected this tube as the great energy absorber.

  18. Power vacuum tubes handbook

    CERN Document Server

    Whitaker, Jerry

    2012-01-01

    Providing examples of applications, Power Vacuum Tubes Handbook, Third Edition examines the underlying technology of each type of power vacuum tube device in common use today. The author presents basic principles, reports on new development efforts, and discusses implementation and maintenance considerations. Supporting mathematical equations and extensive technical illustrations and schematic diagrams help readers understand the material. Translate Principles into Specific Applications This one-stop reference is a hands-on guide for engineering personnel involved in the design, specification,

  19. Strengthening of a railway bridge with NSMR and CFRP tubes

    DEFF Research Database (Denmark)

    Täljsten, Björn; Bennitz, Anders; Danielsson, Georg

    2008-01-01

    Strengthening of structures with CFRP is today considered an accepted method to upgrade concrete structures. In this paper two different CFRP strengthening systems are combined to give extended service life to a Swedish double-trough-double-track railway bridge, constructed in concrete with a 10....... Sensors on bars and tubes display proofs of utilization of the CFRP while displacement sensors and strain gauges on the steel reinforcement due to the small loads in the service limit state show minor effect....

  20. Dynamics of tubes in fluid with tube-baffle interaction

    International Nuclear Information System (INIS)

    Chen, S.S.; Jendrzejczyk, J.A.; Wambsganss, M.W.

    1983-09-01

    Three series of tests are performed to evaluate the effects of tube to tube-support-plate (TSP) clearance on tube dynamic characteristics and instability phenomena for tube arrays in crossflow. Test results show that, for relatively large clearances, tubes may possess TSP-inactive modes in which the tubes rattle inside some of the tube-support-plate holes, and that the natural frequencies of TSP-inactive modes are lower than those of TSP-active modes, in which the support plates provide knife-edge type support. Tube response characteristics associated with TSP-inactive modes are sensitive to tube-to-TSP clearance, TSP thickness, excitation amplitude, tube alignment, and the fluid inside the clearance. In addition, tube response is intrinsically nonlinear, with the dominance of TSP-inactive or TSP-active modes depending on the magnitudes of different system parameters. In general, such a system is difficult to model; only a full-scale test can provide all the necessary characteristics. A tube array supported by TSPs with relatively large clearances may be subjected to dynamic instability in some of the TSP-inactive modes; tube response characteristics and impact forces on TSPs for a tube row are studied in detail in this report. Tube displacements associated with the instability of a TSP-inactive mode are small; however, impacts of the tube against TSPs may result in significant damage in a relatively short time. 52 figures

  1. Alterações oculares em micose fungóide associada com vírus linfotrópico de células t humanas tipo I Ocular fidings in mycosis fungoides associated with human t-lymphotropic virus type I

    Directory of Open Access Journals (Sweden)

    Epaminondas de Souza Mendes Junior

    2010-10-01

    Full Text Available São relatados dois casos da associação de micose fungóide e HTLV-I. Os achados oftalmológicos observados foram, no caso 1: ceratopatia ponteada e ceratoconjuntivite seca e; no caso 2: ceratoconjuntivite seca, espessamento e nódulos difusos em bordas palpebrais. A associação de micose fungóide e HTLV-I nos dois casos sugere envolvimento deste vírus na etiopatogenia da doença. Maior conhecimento e realização de estudos bem controlados poderão ser úteis na determinação precisa desta hipótese.Two cases of mycosis fungoides associated with HTLV-I are reported. The ophthalmological findings were, in the first case, punctate keratopathy and keratoconjunctivitis sicca, and in the second case, keratoconjunctivitis sicca, thickening and difuse nodulos on eyelid margin. The association of mycosis fungoides and HTLV-I in these cases suggests involvement of this agent in the pathogenesis of the disease.

  2. Gastrostomy feeding tube - pump - child

    Science.gov (United States)

    ... tube feeding; PEG tube care; Feeding - gastrostomy tube - pump; G-tube - pump; Gastrostomy button - pump; Bard Button - pump; MIC-KEY - pump ... Gather supplies: Feeding pump (electronic or battery powered) Feeding ... pump (includes a feeding bag, drip chamber, roller clamp, ...

  3. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... search for current job openings visit HHS USAJobs Home >> NEI YouTube Videos >> NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia Animations Blindness Cataract ...

  4. Categorising YouTube

    Directory of Open Access Journals (Sweden)

    Thomas Mosebo Simonsen

    2011-09-01

    Full Text Available This article provides a genre analytical approach to creating a typology of the User Generated Content (UGC of YouTube. The article investigates the construction of navigationprocesses on the YouTube website. It suggests a pragmatic genre approach that is expanded through a focus on YouTube’s technological affordances. Through an analysis of the different pragmatic contexts of YouTube, it is argued that a taxonomic understanding of YouTube must be analysed in regards to the vacillation of a user-driven bottom-up folksonomy and a hierarchical browsing system that emphasises a culture of competition and which favours the already popular content of YouTube. With this taxonomic approach, the UGC videos are registered and analysed in terms of empirically based observations. The article identifies various UGC categories and their principal characteristics. Furthermore, general tendencies of the UGC within the interacting relationship of new and old genres are discussed. It is argued that the utility of a conventional categorical system is primarily of analytical and theoretical interest rather than as a practical instrument.

  5. Three Cell Fusions during Double Fertilization.

    Science.gov (United States)

    Sprunck, Stefanie; Dresselhaus, Thomas

    2015-05-07

    Fertilization of both egg and central cell is a major distinguishing feature of flowering plants. Now, Maruyama et al. report a third cell fusion event between the persistent synergid and the fertilized central cell shortly after double fertilization in Arabidopsis. This causes rapid dilution of pollen tube attractant(s), preventing polytubey. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Fill tube fitted spheres

    International Nuclear Information System (INIS)

    Ives, B.H.

    1981-01-01

    The high temperature diffusion technique for fuel filling of some future direct drive cryogenic ICF targets may be unacceptable. The following describes a technique of fitting a 1 mm diameter x 6 μm thick glass microsphere with an approx. 50 μm O.D. glass fill tube. The process of laser drilling a 50 μm diameter hole in the microsphere wall, technique for making the epoxy joint between the sphere and fill tube, as well as the assembly procedure are also discussed

  7. Steam generator tube vibration study

    International Nuclear Information System (INIS)

    Enderlin, W.I.

    1986-01-01

    Chemical cleaning has been proposed to remove magnetite buildup in some pressurized water reactor steam generators. The US Nuclear Regulatory Commission (NRC) has expressed concern that such cleaning would combine with the tube denting caused by magnetite formation to enlarge tube/tube support plate clearances, increasing the level of flow-induced vibrations that could lead to unacceptably high tube wear and failure rates. In support of NRC, the Pacific Northwest Laboratory investigated whether such increased clearances would exacerbate tube fretting wear. Using a full-length scale model of a steam generator tube bundle, flow tests were conducted at an instrumented location through clearances representing as-built and post-cleaned tube conditions. Test results indicated little potential for increased tube wear as a result of chemical cleaning, under normal operating conditions at tube support locations similar to that tested

  8. Misdirected minitracheostomy tube

    Directory of Open Access Journals (Sweden)

    Ajmer Singh

    2017-01-01

    Full Text Available We report a patient who after an uneventful coronary artery bypass graft surgery and left ventricular aneurysmorrhaphy developed intracerebral hemorrhage and subsequently required minitracheostomy. Chest X-ray showed misdirected minitracheostomy tube facing upward toward the laryngeal opening which was repositioned using bronchoscope.

  9. A New Resonance Tube

    Science.gov (United States)

    Bates, Alan

    2017-01-01

    The measurement of the speed of sound in air with the resonance tube is a popular experiment that often yields accurate results. One approach is to hold a vibrating tuning fork over an air column that is partially immersed in water. The column is raised and lowered in the water until the generated standing wave produces resonance: this occurs at…

  10. Thoughts of accelerator tubes

    International Nuclear Information System (INIS)

    Larson, J.D.

    1977-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators

  11. Thoughts of accelerator tubes

    Energy Technology Data Exchange (ETDEWEB)

    Larson, J D

    1977-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators.

  12. Eustachian Tube Dysfunction

    Science.gov (United States)

    ... When it is inflated, the balloon opens a pathway for mucus and air to flow through the tube. This can help it function properly. FDA warning The U.S. Food and Drug Administration (FDA) advises against the use of ear candles. ...

  13. Tube-dwelling invertebrates

    NARCIS (Netherlands)

    Hölker, Franz; Vanni, Michael J.; Kuiper, Jan J.; Meile, Christof; Grossart, Hans Peter; Stief, Peter; Adrian, Rita; Lorke, Andreas; Dellwig, Olaf; Brand, Andreas; Hupfer, Michael; Mooij, Wolf M.; Nützmann, Gunnar; Lewandowski, Jörg

    2015-01-01

    There is ample evidence that tube-dwelling invertebrates such as chironomids significantly alter multiple important ecosystem functions, particularly in shallow lakes. Chironomids pump large water volumes, and associated suspended and dissolved substances, through the sediment and thereby compete

  14. Chest tube insertion

    Science.gov (United States)

    ... of your chest cavity. This is called the pleural space. It is done to allow your lungs to fully expand. ... pneumothorax ) Fluid buildup in the chest (called a pleural ... in the esophagus (the tube that allows food to go from the mouth ...

  15. Double ambidexterity

    DEFF Research Database (Denmark)

    Kaulio, Matti; Thorén, Kent; Rohrbeck, René

    2017-01-01

    We leverage the business model innovation and ambidexterity literature to investigate a contradictory case, the Swedish-Finnish Telecom operator TeliaSonera. Despite being challenged by three major disruptions, the company not only still exists but also enjoys remarkably good financial performance...... this behaviour as double ambidexterity. We use an in-depth case study to conceptualize double ambidexterity and discuss its impact on the business's survival and enduring success........ Building on extant archival data and interviews, we carefully identify and map 26 organizational responses during 1992–2016. We find that the firm has overcome three critical phases by experimenting and pioneering with portfolios of business models and/or technological innovations. We describe...

  16. Double Chooz

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Christian [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

    2006-05-15

    The goal of the Double Chooz reactor neutrino experiment is to search for the neutrino mixing parameter {theta}{sub 13}. Double Chooz will use two identical detectors at 150 m and 1.05 km distance from the reactor cores. The near detector is used to monitor the reactor {nu}-bar {sub e} flux while the second is dedicated to the search for a deviation from the expected (1/distance){sup 2} behavior. This two detector concept will allow a relative normalization systematic error of ca. 0.6 %. The expected sensitivity for sin{sup 2}2{theta}{sub 13} is then in the range 0.02 - 0.03 after three years of data taking. The antineutrinos will be detected in a liquid scintillator through the capture on protons followed by a gamma cascade, produced by the neutron capture on Gd.

  17. Drift tubes of Linac 2

    CERN Multimedia

    Photographic Service

    1977-01-01

    Being redied for installation, those at the right are for tank 1, those on the left for tank 2. Contrary to Linac 1, which had drift-tubes supported on stems, here the tubes are suspended, for better mechanical stability.

  18. Rubens Flame-Tube Demonstration.

    Science.gov (United States)

    Ficken, George W.; Stephenson, Francis C.

    1979-01-01

    Investigates and explains the phenomenon associated with Rubens flame-tube demonstration, specifically the persistance of flames at regular intervals along the tube for few minutes after the gas is turned off. (GA)

  19. Prospects for stronger calandria tubes

    International Nuclear Information System (INIS)

    Ells, C.E.; Coleman, C.E.; Hosbons, R.R.; Ibrahim, E.F.; Doubt, G.L.

    1990-12-01

    The CANDU calandria tubes, made of seam welded and annealed Zircaloy-2, have given exemplary service in-reactor. Although not designed as a system pressure containment, calandria tubes may remain intact even in the face of pressure tube rupture. One such incident at Pickering Unit 2 demonstrated the economic advantage of such an outcome, and a case can be made for increasing the probability that other calandria tubes would perform in a similar fashion. Various methods of obtaining stronger calandria tubes are available, and reviewed here. When the tubes are internally pressurized, the weld is the weak section of the tube. Increasing the oxygen concentration in the starting sheet, and thickening the weld, are promising routes to a stronger tube

  20. Expansion lyre-shaped tube

    International Nuclear Information System (INIS)

    Andro, Jean.

    1973-01-01

    The invention relates the expansion lyre-shaped tube portions formed in dudgeoned tubular bundles between two bottom plates. An expansion lyre comprises at least two sets of tubes of unequal lengths coplanar and symmetrical with respect to the main tube axis, with connecting portions between the tubes forming said sets. The invention applies to apparatus such as heat exchangers, heaters, superheaters or breeders [fr

  1. NEI You Tube Videos: Amblyopia

    Science.gov (United States)

    ... NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia Animations Blindness Cataract Convergence Insufficiency Diabetic Eye Disease Dilated Eye Exam Dry Eye For Kids Glaucoma Healthy Vision Tips Leber Congenital Amaurosis Low ...

  2. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia Animations Blindness Cataract Convergence Insufficiency Diabetic Eye Disease Dilated Eye Exam Dry Eye For Kids Glaucoma Healthy Vision Tips Leber Congenital Amaurosis Low ...

  3. A study on LMFBR steam generator design without tube failure propagation in water leak events

    International Nuclear Information System (INIS)

    Futagami, Satoshi; Hayafune, Hiroki; Fujimura, Ken; Sato, Mitsuru

    2009-01-01

    The major target performance of the SG for commercialized FBR is not only economic performance but also property protection performance. The candidate SG design will be selected at the end of JFY 2010. The straight double wall tube SG is one of the SG candidates for commercialized FBR, and other SG concepts were studied in this paper. In proposing an alternative SG, alternative technological measures with a double wall tube were investigated and included reinforcing the tube against wastage and quick detection of initial tube leaks. Alternative SG concept candidates for preventing tube failure propagation and mitigation of water leak accidents were proposed through a combination of technological measures. The candidates were then comparatively evaluated from the point of view of property protection performance, total weight, technological issues, and so on. A coated wall tube SG and protective wall tube SG were decided on as the alternative SGs because of superior property protection performance and with the technological issues. At the end of JFY 2010, the straight double wall tube SG will be decided upon as the result of R and D activities, and alternative SGs evaluated in feasibility studies. A plan for studying feasibility with the technological issues of the alternative SG was proposed. (author)

  4. Neutron image intensifier tubes

    International Nuclear Information System (INIS)

    Verat, M.; Rougeot, H.; Driard, B.

    1983-01-01

    The most frequently used techniques in neutron radiography employ a neutron converter consisting of either a scintillator or a thin metal sheet. The radiation created by the neutrons exposes a photographic film that is in contact with the converter: in the direct method, the film is exposed during the time that the object is irradiated with neutrons; in the transfer method, the film is exposed after the irradiation of the object with neutrons. In industrial non-destructive testing, when many identical objects have to be checked, these techniques have several disadvantages. Non-destructive testing systems without these disadvantages can be constructed around neutron-image intensifier tubes. A description and the operating characteristics of neutron-image intensifier tubes are given. (Auth.)

  5. Neural tube defects

    Directory of Open Access Journals (Sweden)

    M.E. Marshall

    1981-09-01

    Full Text Available Neural tube defects refer to any defect in the morphogenesis of the neural tube, the most common types being spina bifida and anencephaly. Spina bifida has been recognised in skeletons found in north-eastern Morocco and estimated to have an age of almost 12 000 years. It was also known to the ancient Greek and Arabian physicians who thought that the bony defect was due to the tumour. The term spina bifida was first used by Professor Nicolai Tulp of Amsterdam in 1652. Many other terms have been used to describe this defect, but spina bifida remains the most useful general term, as it describes the separation of the vertebral elements in the midline.

  6. Stable double helical iodine chains inside single-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Zhen [College of Science, Liaoning University of Technology, Jinzhou, Liaoning, 121001 (China); Liu, Chun-Jian [College of Mathematics and Physics, Bohai University, Jinzhou, Liaoning, 121000 (China); Lv, Hang [Institute of New Energy, Bohai University, Jinzhou, Liaoning, 121000 (China); Liu, Bing-Bing, E-mail: liubb@jlu.edu.cn [State Key Laboratory of Superhard Materials, Jilin University, Changchun, 130012 (China)

    2016-08-12

    The helicity of stable double helical iodine chains inside single-walled carbon nanotubes (SWCNTs) is studied by calculating the systematic interaction energy. Our results present clear images of stable double helical structures inside SWCNTs. The optimum helical radius and helical angle increase and decrease with increasing diameter, respectively. The tube's diameter plays a leading role in the helicity of encapsulated structures, while the tube's chirality may induce different metastable structures. This study indicates that the observed double helical iodine chains in experiments are not necessarily the optimum structures, but may also be metastable structures. - Highlights: • The stable double helical iodine chain inside single-walled carbon nanotubes is proposed. • The influence of tube's diameter and chirality on the stability of encapsulated iodine chains is studied. • The metastable double helical structures may be co-existence with the stable structure but not in the same tubes.

  7. CRL X-ray tube

    International Nuclear Information System (INIS)

    Kolchevsky, N.N.; Petrov, P.V.

    2015-01-01

    A novel types of X-ray tubes with refractive lenses are proposed. CRL-R X-ray tube consists of Compound Refractive Lens- CRL and Reflection X-ray tube. CRL acts as X-ray window. CRL-T X-ray consists of CRL and Transmission X-ray tube. CRL acts as target for electron beam. CRL refractive lens acts as filter, collimator, waveguide and focusing lens. Properties and construction of the CRL X-ray tube are discussed. (authors)

  8. CRL X-RAY TUBE

    OpenAIRE

    Kolchevsky, N. N.; Petrov, P. V.

    2015-01-01

    A novel types of X-ray tubes with refractive lenses are proposed. CRL-R X-ray tube consists of Compound Refractive Lens- CRL and Reflection X-ray tube. CRL acts as X-ray window. CRL-T X-ray consists of CRL and Transmission X-ray tube. CRL acts as target for electron beam. CRL refractive lens acts as filter, collimator, waveguide and focusing lens. Properties and construction of the CRL X-ray tube are discussed.

  9. Localization of actin in pollen tubes of Ornithogalum virens L.

    Directory of Open Access Journals (Sweden)

    Małgorzata Stępka

    2014-01-01

    Full Text Available The germinating pollen grain (in vivo on the stigma or in vitro in germination medium forms a pollen tube which transports the vegetative nucleus and generative cell/two sperm cells participating in the process of double fertilization. The growth of the tube and the transport of organelles and the cells occur due to two major motor systems existing in the pollen tubes of higher plants: the tubuline-dynein/kinesin and the actin-myosin system. In pollen tubes of Ornithogalum virens the actin filaments were labelled with TRITC-phalloidin (2 µg/ml in the PIPES buffer and the 10% sucrose, without the fixative and DMSO. Omission of the fixative and permeabilizing agent (DMSO allowed better preservation of the structure, and the "fluorescence" of actin was observed in living pollen tubes. Observations in CLSM (confocal laser scanning microscope showed that actin is distributed in the vicinity of the cell membrane. This could support the view that actin filaments and the plasmalemma form the pollen tube cortex along which the cytoplasmic movement of organelles, and cell transport occurs.

  10. Multi objective optimization of foam-filled circular tubes for quasi-static and dynamic responses

    Directory of Open Access Journals (Sweden)

    Fauzan Djamaluddin

    Full Text Available AbstractFuel consumption and safety are currently key aspects in automobile design. The foam-filled thin-walled aluminium tube represents a potentially effective material for use in the automotive industry, due to its energy absorption capability and light weight. Multi-objective crashworthiness design optimization for foam-filled double cylindrical tubes is presented in this paper. The double structures are impacted by a rigid wall simulating quasi-static and dynamic loadings. The optimal parameters under consideration are the minimum peak crushing force and maximum specific energy absorption, using the non-dominated sorting genetic algorithm-II (NSGA-II technique. Radial basis functions (RBF and D-Optimal are adopted to determine the more complex crashworthiness functional objectives. The comparison is performed by finite element analysis of the impact crashworthiness characteristics in tubes under static and dynamic loads. Finally, the optimum crashworthiness performance of empty and foam-filled double tubes is investigated and compared to the traditional single foam-filled tube. The results indicate that the foam-filled double aluminium circular tube can be recommended for crashworthy structures.

  11. Free compression tube. Applications

    Science.gov (United States)

    Rusu, Ioan

    2012-11-01

    During the flight of vehicles, their propulsion energy must overcome gravity, to ensure the displacement of air masses on vehicle trajectory, to cover both energy losses from the friction between a solid surface and the air and also the kinetic energy of reflected air masses due to the impact with the flying vehicle. The flight optimization by increasing speed and reducing fuel consumption has directed research in the aerodynamics field. The flying vehicles shapes obtained through studies in the wind tunnel provide the optimization of the impact with the air masses and the airflow along the vehicle. By energy balance studies for vehicles in flight, the author Ioan Rusu directed his research in reducing the energy lost at vehicle impact with air masses. In this respect as compared to classical solutions for building flight vehicles aerodynamic surfaces which reduce the impact and friction with air masses, Ioan Rusu has invented a device which he named free compression tube for rockets, registered with the State Office for Inventions and Trademarks of Romania, OSIM, deposit f 2011 0352. Mounted in front of flight vehicles it eliminates significantly the impact and friction of air masses with the vehicle solid. The air masses come into contact with the air inside the free compression tube and the air-solid friction is eliminated and replaced by air to air friction.

  12. Shock tube Multiphase Experiments

    Science.gov (United States)

    Middlebrooks, John; Allen, Roy; Paudel, Manoj; Young, Calvin; Musick, Ben; McFarland, Jacob

    2017-11-01

    Shock driven multiphase instabilities (SDMI) are unique physical phenomena that have far-reaching practical applications in engineering and science. The instability is present in high energy explosions, scramjet combustors, and supernovae events. The SDMI arises when a multiphase interface is impulsively accelerated by the passage of a shockwave. It is similar in development to the Richtmyer-Meshkov (RM) instability however, particle-to-gas coupling is the driving mechanism of the SDMI. As particle effects such as lag and phase change become more prominent, the SDMI's development begins to significantly deviate from the RM instability. We have developed an experiment for studying the SDMI in our shock tube facility. In our experiments, a multiphase interface is created using a laminar jet and flowed into the shock tube where it is accelerated by the passage of a planar shockwave. The interface development is captured using CCD cameras synchronized with planar laser illumination. This talk will give an overview of new experiments conducted to examine the development of a shocked cylindrical multiphase interface. The effects of Atwood number, particle size, and a second acceleration (reshock) of the interface will be discussed.

  13. Establishment of the male germline and sperm cell movement during pollen germination and tube growth in maize

    OpenAIRE

    Kliwer, Irina; Dresselhaus, Thomas

    2010-01-01

    Two sperm cells are required to achieve double fertilization in flowering plants (angiosperms). In contrast to animals and lower plants such as mosses and ferns, sperm cells of flowering plants (angiosperms) are immobile and are transported to the female gametes (egg and central cell) via the pollen tube. The two sperm cells arise from the generative pollen cell either within the pollen grain or after germination inside the pollen tube. While pollen tube growth and sperm behavior has been int...

  14. Doubling Syndemics

    Science.gov (United States)

    2017-01-01

    Abstract This study investigates health concerns and access to health services for Roma from Romania who live in homelessness in Copenhagen, Denmark. They collect refundable bottles and call themselves “badocari,” which in Romanian refers to “people who work with bottles.” Homeless Roma in Denmark have not previously been studied through ethnographic research. The study stresses the importance of a syndemic approach towards understanding badocari health concerns. Syndemics is understood as co-occurring diseases, which unfold within contexts of social injustice. The case of the badocari is argued to be a case of “doubling syndemics” since the co-occurring diseases are further multiplied and enhanced by an ongoing mobility between dual contexts of precarious livelihoods in Romania and Denmark, respectively. The study complements the approach to syndemics with a perspective on human rights. It sheds light on the limited possibilities that exist for addressing health concerns of the badocari, both in Romania and in Denmark, and argues that the universal human right to health is not realized in the everyday lives of destitute EU migrants such as the badocari. Rather, they experience lack of access to adequate medical treatment and follow-up care, both as citizens of a member state and as co-citizens of the European Union. PMID:29302164

  15. Bacterial Biofilms in Jones Tubes.

    Science.gov (United States)

    Ahn, Eric S; Hauck, Matthew J; Kirk Harris, Jonathan; Robertson, Charles E; Dailey, Roger A

    To investigate the presence and microbiology of bacterial biofilms on Jones tubes (JTs) by direct visualization with scanning electron microscopy and polymerase chain reaction (PCR) of representative JTs, and to correlate these findings with inflammation and/or infection related to the JT. In this study, prospective case series were performed. JTs were recovered from consecutive patients presenting to clinic for routine cleaning or recurrent irritation/infection. Four tubes were processed for scanning electron microscopy alone to visualize evidence of biofilms. Two tubes underwent PCR alone for bacterial quantification. One tube was divided in half and sent for scanning electron microscopy and PCR. Symptoms related to the JTs were recorded at the time of recovery. Seven tubes were obtained. Five underwent SEM, and 3 out of 5 showed evidence of biofilms (60%). Two of the 3 biofilms demonstrated cocci and the third revealed rods. Three tubes underwent PCR. The predominant bacteria identified were Pseudomonadales (39%), Pseudomonas (16%), and Staphylococcus (14%). Three of the 7 patients (43%) reported irritation and discharge at presentation. Two symptomatic patients, whose tubes were imaged only, revealed biofilms. The third symptomatic patient's tube underwent PCR only, showing predominantly Staphylococcus (56%) and Haemophilus (36%) species. Two of the 4 asymptomatic patients also showed biofilms. All symptomatic patients improved rapidly after tube exchange and steroid antibiotic drops. Bacterial biofilms were variably present on JTs, and did not always correlate with patients' symptoms. Nevertheless, routine JT cleaning is recommended to treat and possibly prevent inflammation caused by biofilms.

  16. Failure analysis of boiler tube

    International Nuclear Information System (INIS)

    Mehmood, K.; Siddiqui, A.R.

    2007-01-01

    Boiler tubes are energy conversion components where heat energy is used to convert water into high pressure superheated steam, which is then delivered to a turbine for electric power generation in thermal power plants or to run plant and machineries in a process or manufacturing industry. It was reported that one of the tubes of a fire-tube boiler used in a local industry had leakage after the formation of pits at the external surface of the tube. The inner side of the fire tube was working with hot flue gasses with a pressure of 10 Kg/cm/sup 2/ and temperature 225 degree C. The outside of the tube was surrounded by feed water. The purpose of this study was to determine the cause of pits developed at the external surface of the failed boiler tube sample. In the present work boiler tube samples of steel grade ASTM AI61/ASTM A192 were analyzed using metallographic analysis, chemical analysis, and mechanical testing. It was concluded that the appearance of defects on the boiler tube sample indicates cavitation type corrosion failure. Cavitation damage superficially resembled pitting, but surface appeared considerably rougher and had many closely spaced pits. (author)

  17. YouTube and 'psychiatry'.

    Science.gov (United States)

    Gordon, Robert; Miller, John; Collins, Noel

    2015-12-01

    YouTube is a video-sharing website that is increasingly used to share and disseminate health-related information, particularly among younger people. There are reports that social media sites, such as YouTube, are being used to communicate an anti-psychiatry message but this has never been confirmed in any published analysis of YouTube clip content. This descriptive study revealed that the representation of 'psychiatry' during summer 2012 was predominantly negative. A subsequent smaller re-analysis suggests that the negative portrayal of 'psychiatry' on YouTube is a stable phenomenon. The significance of this and how it could be addressed are discussed.

  18. Radiation-resistant camera tube

    International Nuclear Information System (INIS)

    Kuwahata, Takao; Manabe, Sohei; Makishima, Yasuhiro

    1982-01-01

    It was a long time ago that Toshiba launched on manufacturing black-and-white radiation-resistant camera tubes employing nonbrowning face-plate glass for ITV cameras used in nuclear power plants. Now in compliance with the increasing demand in nuclear power field, the Company is at grips with the development of radiation-resistant single color-camera tubes incorporating a color-stripe filter for color ITV cameras used under radiation environment. Herein represented are the results of experiments on characteristics of materials for single color-camera tubes and prospects for commercialization of the tubes. (author)

  19. Learning from YouTube [Video Book

    Science.gov (United States)

    Juhasz, Alexandra

    2011-01-01

    YouTube is a mess. YouTube is for amateurs. YouTube dissolves the real. YouTube is host to inconceivable combos. YouTube is best for corporate-made community. YouTube is badly baked. These are a few of the things Media Studies professor Alexandra Juhasz (and her class) learned about YouTube when she set out to investigate what actually happens…

  20. Double inflation

    International Nuclear Information System (INIS)

    Silk, J.; Turner, M.S.

    1986-04-01

    The Zel'dovich spectrum of adiabatic density perturbations is a generic prediction of inflation. There is increasing evidence that when the spectrum is normalized by observational data on small scales, there is not enough power on large scales to account for the observed large-scale structure in the Universe. Decoupling the spectrum on large and small scales could solve this problem. As a means of decoupling the large and small scales we propose double inflation (i.e., two episodes of inflation). In this scenario the spectrum on large scales is determined by the first episode of inflation and those on small scales by a second episode of inflation. We present three models for such a scenario. By nearly saturating the large angular-scale cosmic microwave anisotropy bound, we can easily account for the observed large-scale structure. We take the perturbations on small scales to be very large, deltarho/rho approx. = 0.1 to 0.01, which results in the production of primordial black holes (PBHs), early formation of structure, reionization of the Universe, and a rich array of astrophysical events. The Ω-problem is also addressed by our scenario. Allowing the density perturbations produced by the second episode of inflation to be large also lessens the fine-tuning required in the scalar potential and makes reheating much easier. We briefly speculate on the possibility that the second episode of inflation proceeds through the nucleation of bubbles, which today manifest themselves as empty bubbles whose surfaces are covered with galaxies. 37 refs., 1 fig

  1. Tube to tube excursive instability - sensitivities and transients

    International Nuclear Information System (INIS)

    Brown, M.; Layland, M.W.

    1980-01-01

    A simple basic analysis of excursive instability in a boiler tube shows how it depends upon operating conditions and physical properties. A detailed mathematical model of an AGR boiler is used to conduct a steady state parameter sensitivity survey. It is possible from this basis to anticipate the effects of changes in operating conditions and changes in design parameters upon tube to tube stability. Dynamic responses of tubes operating near the stability threshold are examined using a mathematical model. Simulated excursions are triggered by imparting small abrupt pressure changes on the boiler inlet pressure. The influences of the magnitude of the pressure change, waterside friction factor and gas side coupling between tubes are examined. (author)

  2. Nasogastric tube syndrome induced by an indwelling long intestinal tube.

    Science.gov (United States)

    Sano, Naoki; Yamamoto, Masayoshi; Nagai, Kentaro; Yamada, Keiichi; Ohkohchi, Nobuhiro

    2016-04-21

    The nasogastric tube (NGT) has become a frequently used device to alleviate gastrointestinal symptoms. Nasogastric tube syndrome (NTS) is an uncommon but potentially life-threatening complication of an indwelling NGT. NTS is characterized by acute upper airway obstruction due to bilateral vocal cord paralysis. We report a case of a 76-year-old man with NTS, induced by an indwelling long intestinal tube. He was admitted to our hospital for treatment of sigmoid colon cancer. He underwent sigmoidectomy to release a bowel obstruction, and had a long intestinal tube inserted to decompress the intestinal tract. He presented acute dyspnea following prolonged intestinal intubation, and bronchoscopy showed bilateral vocal cord paralysis. The NGT was removed immediately, and tracheotomy was performed. The patient was finally discharged in a fully recovered state. NTS be considered in patients complaining of acute upper airway obstruction, not only with a NGT inserted but also with a long intestinal tube.

  3. A New Resonance Tube

    Science.gov (United States)

    Bates, Alan

    2017-12-01

    The measurement of the speed of sound in air with the resonance tube is a popular experiment that often yields accurate results. One approach is to hold a vibrating tuning fork over an air column that is partially immersed in water. The column is raised and lowered in the water until the generated standing wave produces resonance: this occurs at the point where sound is perceived to have maximum loudness, or at the point where the amplitude of the standing wave has maximum value, namely an antinode. An antinode coincides with the position of the tuning fork, beyond the end of the air column, which consequently introduces an end correction. One way to minimize this end correction is to measure the distance between consecutive antinodes.

  4. Piezoelectric Rotary Tube Motor

    Science.gov (United States)

    Fisher, Charles D.; Badescu, Mircea; Braun, David F.; Culhane, Robert

    2011-01-01

    A custom rotary SQUIGGLE(Registered TradeMark) motor has been developed that sets new benchmarks for small motor size, high position resolution, and high torque without gear reduction. Its capabilities cannot be achieved with conventional electromagnetic motors. It consists of piezoelectric plates mounted on a square flexible tube. The plates are actuated via voltage waveforms 90 out of phase at the resonant frequency of the device to create rotary motion. The motors were incorporated into a two-axis postioner that was designed for fiber-fed spectroscopy for ground-based and space-based projects. The positioner enables large-scale celestial object surveys to take place in a practical amount of time.

  5. Pressure tube reactor

    International Nuclear Information System (INIS)

    Matsumoto, Tomoyuki; Fujino, Michihira.

    1980-01-01

    Purpose: To equalize heavy water flow distribution by providing a nozzle for externally injecting heavy water from a vibration preventive plate to the upper portion to feed the heavy water in a pressure tube reactor and swallowing up heavy water in a calandria tank to supply the heavy water to the reactor core above the vibration preventive plate. Constitution: A moderator injection nozzle is mounted on the inner wall of a calandria tank. Heavy water is externally injected above the vibration preventive plate, and heavy water in the calandria tank is swallowed up to supply the heavy water to the core reactor above the vibration preventive plate. Therefore, the heavy water flow distribution can be equalized over the entire reactor core, and the distribution of neutron absorber dissolved in the heavy water is equalized. (Yoshihara, H.)

  6. Primary Fallopian Tube Carcinoma

    Directory of Open Access Journals (Sweden)

    Prasad K Shetty

    2011-01-01

    Full Text Available Primary Fallopian Tube Carcinoma (PFTC is rare and accounts for about 0.3% of all gynecologic cancers. Less than 1500 cases have been reported in the literature. It arises in postmenopausal women and typically presents with abdominal pelvic pain, vaginal bleeding and watery discharge. However, a correct diagnosis is rarely achieved preoperative, and in many cases, the diagnosis is made after incidental surgery for unrelated conditions commonly being ovarian carcinoma . Compared with ovarian carcinoma, PFTC more often presents at early stages, but it has a worse prognosis. PFTC is usually managed in the same manner as ovarian cancer. We report a case of Left PFTC that presented as Left ovarian mass, and we briefly review the literature.

  7. Characterization of tube support alloys

    International Nuclear Information System (INIS)

    Vaia, A.R.

    1985-01-01

    The involvement and relationship of carbon steel corrosion products in the tube denting phenomenon promoted an intensive research effort to: 1) understand, reproduce, and arrest the denting process, and 2) evaluate alternative tube support materials to provide additional corrosion resistance. The paper summarizes a corrosion testing program for the verification of type 405 stainless steel under acid or all volatile treatment conditions

  8. Flaming on YouTube

    NARCIS (Netherlands)

    Moor, Peter J.; Heuvelman, A.; Verleur, R.

    2010-01-01

    In this explorative study, flaming on YouTube was studied using surveys of YouTube users. Flaming is defined as displaying hostility by insulting, swearing or using otherwise offensive language. Three general conclusions were drawn. First, although many users said that they themselves do not flame,

  9. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... Amaurosis Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: Amblyopia NEI Home Contact Us A-Z Site Map NEI on Social Media Information in Spanish (Información en español) Website, ...

  10. 27 CFR 40.352 - Cigarette tubes.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Cigarette tubes. 40.352... OF THE TREASURY (CONTINUED) TOBACCO MANUFACTURE OF TOBACCO PRODUCTS, CIGARETTE PAPERS AND TUBES, AND PROCESSED TOBACCO Manufacture of Cigarette Papers and Tubes Taxes § 40.352 Cigarette tubes. Cigarette tubes...

  11. Integrated straight - through automatic non-destructive examination and data acquisition system for thin-wall tubes

    International Nuclear Information System (INIS)

    Stoessel, A.; Boulanger, G.; Furlan, J.; Mogavero, R.

    1981-09-01

    This non-destructive testing unit inspects the cladding tubes for the SUPER-PHENIX fast neutron reactor. The quality level demanded for these tubes, as well as their number, required designing an installation that combined high performance with a great testing rate and complete automation. The testing is effected under immersion by means of six transducers, focused in line, working at 30 MHz. The tubes are numbered on an automatic rig; marking is by dark rings obtained by superficial electrolysis of the tube and regularly distributed on the abscissa; the quality of the tube is not affected by this. The advantage of this numbering system is that it enables the tubes to be fed to the test set in any order. An acquisition unit, constituted of a microprocessor, a semi-graphical printer and a double floppy disk unit, makes it possible to enter, edit and store the information for each tube [fr

  12. Double hard scattering without double counting

    Science.gov (United States)

    Diehl, Markus; Gaunt, Jonathan R.; Schönwald, Kay

    2017-06-01

    Double parton scattering in proton-proton collisions includes kinematic regions in which two partons inside a proton originate from the perturbative splitting of a single parton. This leads to a double counting problem between single and double hard scattering. We present a solution to this problem, which allows for the definition of double parton distributions as operator matrix elements in a proton, and which can be used at higher orders in perturbation theory. We show how the evaluation of double hard scattering in this framework can provide a rough estimate for the size of the higher-order contributions to single hard scattering that are affected by double counting. In a numeric study, we identify situations in which these higher-order contributions must be explicitly calculated and included if one wants to attain an accuracy at which double hard scattering becomes relevant, and other situations where such contributions may be neglected.

  13. Double hard scattering without double counting

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, Markus [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Gaunt, Jonathan R. [VU Univ. Amsterdam (Netherlands). NIKHEF Theory Group; Schoenwald, Kay [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2017-02-15

    Double parton scattering in proton-proton collisions includes kinematic regions in which two partons inside a proton originate from the perturbative splitting of a single parton. This leads to a double counting problem between single and double hard scattering. We present a solution to this problem, which allows for the definition of double parton distributions as operator matrix elements in a proton, and which can be used at higher orders in perturbation theory. We show how the evaluation of double hard scattering in this framework can provide a rough estimate for the size of the higher-order contributions to single hard scattering that are affected by double counting. In a numeric study, we identify situations in which these higher-order contributions must be explicitly calculated and included if one wants to attain an accuracy at which double hard scattering becomes relevant, and other situations where such contributions may be neglected.

  14. HF electronic tubes. Technologies, grid tubes and klystrons

    International Nuclear Information System (INIS)

    Lemoine, Th.

    2009-01-01

    This article gives an overview of the basic technologies of electronic tubes: cathodes, electronic optics, vacuum and high voltage. Then the grid tubes, klystrons and inductive output tubes (IOT) are introduced. Content: 1 - context and classification; 2 - electronic tube technologies: cathodes, electronic optics, magnetic confinement (linear tubes), periodic permanent magnet (PPM) focussing, collectors, depressed collectors; 3 - vacuum technologies: vacuum quality, surface effects and interaction with electrostatic and RF fields, secondary emission, multipactor effect, thermo-electronic emission; 4 - grid tubes: operation of a triode, tetrodes, dynamic operation and classes of use, 'common grid' and 'common cathode' operation, ranges of utilisation and limitations, operation of a tetrode on unadjusted load, lifetime of a tetrode, uses of grid tubes; 5 - klystrons: operation, impact of space charge, multi-cavity klystrons, interaction efficiency, extended interaction klystrons, relation between interaction efficiency, perveance and efficiency, ranges of utilization and power limitations, multi-beam klystrons and sheet beam klystrons, operation on unadjusted load, klystron band pass and lifetime, uses; 6 - IOT: principle of operation, ranges of utilisation and limitations, interaction efficiency and depressed collector IOT, IOT lifetime and uses. (J.S.)

  15. Pulsed Drift Tube Accelerator

    International Nuclear Information System (INIS)

    Faltens, A.

    2004-01-01

    The pulsed drift-tube accelerator (DTA) concept was revived by Joe Kwan and John Staples and is being considered for the HEDP/WDM application. It could be used to reach the full energy or as an intermediate accelerator between the diode and a high gradient accelerator such as multi-beam r.f. In the earliest LBNL HIF proposals and conceptual drivers it was used as an extended injector to reach energies where an induction linac with magnetic quadrupoles is the best choice. For HEDP, because of the very short pulse duration, the DTA could provide an acceleration rate of about 1MV/m. This note is divided into two parts: the first, a design based on existing experience; the second, an optimistic extrapolation. The first accelerates 16 parallel K + beams at a constant line charge density of 0.25(micro) C/m per beam to 10 MeV; the second uses a stripper and charge selector at around 4MeV followed by further acceleration to reach 40 MeV. Both benefit from more compact sources than the present 2MV injector source, although that beam is the basis of the first design and is a viable option. A pulsed drift-tube accelerator was the first major HIF experiment at LBNL. It was designed to produce a 2(micro)s rectangular 1 Ampere C s + beam at 2MeV. It ran comfortably at 1.6MeV for several years, then at lower voltages and currents for other experiments, and remnants of that experiment are in use in present experiments, still running 25 years later. The 1A current, completely equivalent to 1.8A K + , was chosen to be intermediate between the beamlets appropriate for a multi-beam accelerator, and a single beam of, say, 10A, at injection energies. The original driver scenarios using one large beam on each side of the reactor rapidly fell out of favor because of the very high transverse and longitudinal fields from the beam space charge, circa 1MV/cm and 250 kV/cm respectively, near the chamber and because of aberrations in focusing a large diameter beam down to a 1mm radius spot at a

  16. Water-storage-tube systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hemker, P.

    1981-12-24

    Passive solar collection/storage/distribution systems were surveyed, designed, fabricated, and mechanically and thermally tested. The types studied were clear and opaque fiberglass tubes, metal tubes with plastic liners, and thermosyphoning tubes. (MHR)

  17. Conditioning and breakdown phenomena in accelerator tubes

    International Nuclear Information System (INIS)

    Skorka, S.J.

    1979-01-01

    Important breakdown mechanisms in accelerator tubes are reviewed, and discharge phenomena in NEC tubes are deduced from the surface appearance of the electrodes and insulators of a used tube. Microphotos of these surfaces are shown

  18. Eddy current signal comparison for tube identification

    Science.gov (United States)

    Glass, S. W.; Vojvodic, R.

    2015-03-01

    Inspection of nuclear power plant steam generator tubes is required to justify continued safe plant operation. The steam generators consist of thousands of tubes with nominal diameters of 15 to 22mm, approximately 1mm wall thickness, and 20 to 30m in length. The tubes are inspected by passing an eddy current probe through the tubes from tube end to tube end. It is critical to know exactly which tube identification (row and column) is associated with each tube's data. This is controlled by a precision manipulator that provides the tube ID to the eddy current system. Historically there have been some instances where the manipulator incorrectly reported the tube ID. This can have serious consequences including lack of inspection of a tube, or if a pluggable indication is detected, the tube is likely to be mis-plugged thereby risking a primary to secondary leak.

  19. mouseTube

    Science.gov (United States)

    Torquet, Nicolas; de Chaumont, Fabrice; Faure, Philippe; Bourgeron, Thomas; Ey, Elodie

    2016-01-01

    Ultrasonic vocalisation is a broadly used proxy to evaluate social communication in mouse models of neuropsychiatric disorders. The efficacy and robustness of testing these models suffer from limited knowledge of the structure and functions of these vocalisations as well as of the way to analyse the data. We created mouseTube , an open database with a web interface, to facilitate sharing and comparison of ultrasonic vocalisations data and metadata attached to a recording file. Metadata describe 1) the acquisition procedure, e.g ., hardware, software, sampling frequency, bit depth; 2) the biological protocol used to elicit ultrasonic vocalisations; 3) the characteristics of the individual emitting ultrasonic vocalisations ( e.g. , strain, sex, age). To promote open science and enable reproducibility, data are made freely available. The website provides searching functions to facilitate the retrieval of recording files of interest. It is designed to enable comparisons of ultrasonic vocalisation emission between strains, protocols or laboratories, as well as to test different analysis algorithms and to search for protocols established to elicit mouse ultrasonic vocalisations. Over the long term, users will be able to download and compare different analysis results for each data file. Such application will boost the knowledge on mouse ultrasonic communication and stimulate sharing and comparison of automatic analysis methods to refine phenotyping techniques in mouse models of neuropsychiatric disorders.

  20. X-ray tube

    International Nuclear Information System (INIS)

    Mayo, B.J.

    1980-01-01

    An x-ray tube in which the x-ray origin is scanned on a circle around the patient, comprises a ring-shaped anode, an electron beam travelling along a circular path being deflected onto the anode at the desired positions. The electron beam path may be in a plane parallel to the anode and perhaps at the same radius. It may be in the same plane as a transmission target/anode and at a greater radius. The anode should extend over at least 180 0 although it may extend to 360 0 . Electrostatic means may be provided to constrain the beam to the circular path and further electrostatic means deflect it to the anode of the beam and ensure it is focused at the point of incidence. Collimators provide a planar fan-shaped beam and the anode may be shaped to attenuate side lobes of the radiation. Electrode collects electrons not deflected. The focal regions may be adjacent or otherwise. Coils may provide periodic focusing to overcome space charge dispersion and dynamic adjustment of the focusing before deflection ensures focusing at target incidence. Focusing may be absent near the deflection region, and current in the coil section near the focal region should be zero. (author)

  1. Flux tubes at finite temperature

    Energy Technology Data Exchange (ETDEWEB)

    Cea, Paolo [INFN, Sezione di Bari,Via G. Amendola 173, I-70126 Bari (Italy); Dipartimento di Fisica dell’Università di Bari,Via G. Amendola 173, I-70126 Bari (Italy); Cosmai, Leonardo [INFN, Sezione di Bari,Via G. Amendola 173, I-70126 Bari (Italy); Cuteri, Francesca; Papa, Alessandro [Dipartimento di Fisica, Università della Calabria & INFN-Cosenza,Ponte Bucci, cubo 31C, I-87036 Rende (Cosenza) (Italy)

    2016-06-07

    The chromoelectric field generated by a static quark-antiquark pair, with its peculiar tube-like shape, can be nicely described, at zero temperature, within the dual superconductor scenario for the QCD confining vacuum. In this work we investigate, by lattice Monte Carlo simulations of the SU(3) pure gauge theory, the fate of chromoelectric flux tubes across the deconfinement transition. We find that, if the distance between the static sources is kept fixed at about 0.76 fm ≃1.6/√σ and the temperature is increased towards and above the deconfinement temperature T{sub c}, the amplitude of the field inside the flux tube gets smaller, while the shape of the flux tube does not vary appreciably across deconfinement. This scenario with flux-tube “evaporation” above T{sub c} has no correspondence in ordinary (type-II) superconductivity, where instead the transition to the phase with normal conductivity is characterized by a divergent fattening of flux tubes as the transition temperature is approached from below. We present also some evidence about the existence of flux-tube structures in the magnetic sector of the theory in the deconfined phase.

  2. Measurement of Work Generation and Improvement in Performance of a Pulse Tube Engine

    Science.gov (United States)

    Hamaguchi, Kazuhiro; Futagi, Hiroaki; Yazaki, Taichi; Hiratsuka, Yoshikatsu

    Apart from double acting type engines, Stirling engines have either 2 pistons in 2 cylinders or 2 pistons in a single cylinder. Typically, the heater, regenerator and cooler are installed between the 2 pistons. The pulse tube engine, on the other hand, consists of a single piston in a single cylinder, a pulse tube, a heater, a regenerator, a cooler and a second cooler. For this paper, a simple prototype engine that uses air at normal atmospheric pressure as the working gas was fabricated. The oscillating velocity of the working gas in the pulse tube was measured using LDV, and the work flow emitting out of the pulse tube was observed. In addition, the effect of inserting heat storage material in the pulse tube on shaft power and indicated power was examined experimentally. A dramatic increase in the shaft power was achieved.

  3. PEG tubes: dealing with complications.

    Science.gov (United States)

    Malhi, Hardip; Thompson, Rosie

    A percutaneous endoscopic gastronomy tube can be used to deliver nutrition, hydration and medicines directly into the patient's stomach. Patients will require a tube if they are unable to swallow safely, putting them at risk of aspiration of food, drink and medicines into their lungs. It is vital that nurses are aware of the complications that may arise when caring for a patient with a PEG tube. It is equally important that nurses know how to deal with these complications or from where tc seek advice. This article provides a quick troubleshooting guide to help nurses deal with complications that can arise with PEG feeding.

  4. Rigid inflatable gastrostomy tube malposition

    Directory of Open Access Journals (Sweden)

    Timothy E. Murray, MB, MCh, MRCS, FFR

    2017-12-01

    Full Text Available Rigid inflatable gastrostomy (RIG tubes are widely used in contemporary clinical practice for a variety of indications. Insertion of RIG tubes is associated with a high technical success rate and low incidence of mortality. In this case report, a procedural pitfall associated with intraperitoneal-extragastric malposition is described. Rigorous assessment of abdominal radiographs, as well as awareness of the expected appearance of the RIG tube and gastropexy T-fasteners, allows the abdominal radiologist to detect early RIG position in the early postprocedural period. Abdominal radiography is a widely available and inexpensive technique. The high spatial resolution it provides makes it a valuable tool in determining hardware position.

  5. Expansion tube test time predictions

    Science.gov (United States)

    Gourlay, Christopher M.

    1988-01-01

    The interaction of an interface between two gases and strong expansion is investigated and the effect on flow in an expansion tube is examined. Two mechanisms for the unsteady Pitot-pressure fluctuations found in the test section of an expansion tube are proposed. The first mechanism depends on the Rayleigh-Taylor instability of the driver-test gas interface in the presence of a strong expansion. The second mechanism depends on the reflection of the strong expansion from the interface. Predictions compare favorably with experimental results. The theory is expected to be independent of the absolute values of the initial expansion tube filling pressures.

  6. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... and Aging Program African American Program Training and Jobs Fellowships NEI Summer Intern Program Diversity In Vision ... DIVRO) Student Training Programs To search for current job openings visit HHS USAJobs Home >> NEI YouTube Videos >> ...

  7. Tube-wave seismic imaging

    Science.gov (United States)

    Korneev, Valeri A [LaFayette, CA

    2009-05-05

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  8. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... and Aging Program African American Program Training and Jobs Fellowships NEI Summer Intern Program Diversity In Vision ... DIVRO) Student Training Programs To search for current job openings visit HHS USAJobs Home > NEI YouTube Videos > ...

  9. Lunar Core Drive Tubes Summary

    Data.gov (United States)

    National Aeronautics and Space Administration — Contains a brief summary and high resolution imagery from various lunar rock and core drive tubes collected from the Apollo and Luna missions to the moon.

  10. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... questions Clinical Studies Publications Catalog Photos and Images Spanish Language Information Grants and Funding Extramural Research Division ... Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video ...

  11. Conditioning of NEC accelerator tubes

    International Nuclear Information System (INIS)

    Yntema, J.L.

    1979-01-01

    The conditioning process of NEC tubes was investigated by recording the fluctuations observed with a residual gas analyzer for a fixed mass and a simultaneous recording of the current fluctuations in background pressure

  12. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino ... To search for current job openings visit HHS USAJobs Home » NEI YouTube ...

  13. Eddy current tube testing unit

    International Nuclear Information System (INIS)

    Dufayet, J.P.; Duret, G.

    1975-01-01

    The unit described can check a wide variety of tubes in quick succession and its modular design gives it a high degree of versability. Suitably defined working conditions and specific fittings enable most of the faults encountered in the manufacture of a tube to be detected. By appropriate means of selection based on signal amplitude, phase and frequency analyses it is possible to adapt selection criteria to the seriousness of the different categories of defect [fr

  14. Electronics for proportional drift tubes

    International Nuclear Information System (INIS)

    Fremont, G.; Friend, B.; Mess, K.H.; Schmidt-Parzefall, W.; Tarle, J.C.; Verweij, H.; CERN-Hamburg-Amsterdam-Rome-Moscow Collaboration); Geske, K.; Riege, H.; Schuett, J.; CERN-Hamburg-Amsterdam-Rome-Moscow Collaboration); Semenov, Y.; CERN-Hamburg-Amsterdam-Rome-Moscow Collaboration)

    1980-01-01

    An electronic system for the read-out of a large number of proportional drift tubes (16,000) has been designed. This system measures deposited charge and drift-time of the charge of a particle traversing a proportional drift tube. A second event can be accepted during the read-out of the system. Up to 40 typical events can be collected and buffered before a data transfer to a computer is necessary. (orig.)

  15. The YouTube reader

    OpenAIRE

    Snickars, Pelle; Vonderau, Patrick

    2009-01-01

    YouTube has come to epitomize the possibilities of digital culture. With more than seventy million unique users a month and approximately eighty million videos online, this brand-name video distribution platform holds the richest repository of popular culture on the Internet. As the fastest growing site in the history of the Web, YouTube promises endless new opportunities for amateur video, political campaigning, entertainment formats, and viral marketing—a clip culture that has seemed to out...

  16. Dermatology on YouTube.

    Science.gov (United States)

    Boyers, Lindsay N; Quest, Tyler; Karimkhani, Chante; Connett, Jessica; Dellavalle, Robert P

    2014-06-15

    YouTube, reaches upwards of six billion users on a monthly basis and is a unique source of information distribution and communication. Although the influence of YouTube on personal health decision-making is well established, this study assessed the type of content and viewership on a broad scope of dermatology related content on YouTube. Select terms (i.e. dermatology, sun protection, skin cancer, skin cancer awareness, and skin conditions) were searched on YouTube. Overall, the results included 100 videos with over 47 million viewers. Advocacy was the most prevalent content type at 24% of the total search results. These 100 videos were "shared" a total of 101,173 times and have driven 6,325 subscriptions to distinct YouTube user pages. Of the total videos, 35% were uploaded by or featured an MD/DO/PhD in dermatology or other specialty/field, 2% FNP/PA, 1% RN, and 62% other. As one of the most trafficked global sites on the Internet, YouTube is a valuable resource for dermatologists, physicians in other specialties, and the general public to share their dermatology-related content and gain subscribers. However, challenges of accessing and determining evidence-based data remain an issue.

  17. 21 CFR 872.6570 - Impression tube.

    Science.gov (United States)

    2010-04-01

    ... DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6570 Impression tube. (a) Identification. An impression tube is a device consisting of a hollow copper tube intended to take an impression of a single tooth... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Impression tube. 872.6570 Section 872.6570 Food...

  18. 27 CFR 41.35 - Cigarette tubes.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Cigarette tubes. 41.35... OF THE TREASURY (CONTINUED) TOBACCO IMPORTATION OF TOBACCO PRODUCTS, CIGARETTE PAPERS AND TUBES, AND PROCESSED TOBACCO Taxes Tax Rates § 41.35 Cigarette tubes. Cigarette tubes are taxed at the following rates...

  19. Tubing vs. buckets: a cost comparison

    Science.gov (United States)

    Neil K. Huyler

    1975-01-01

    Equipment investment for tubing-vacuum systems was significantly less than that for bucket systems. Tubing-vacuum systems required about 22 percent less labor input, the major labor input being completed before sap-flow periods. Annual cost of operation was less for tubing-vacuum than the bucket system. Small tubing-vacuum operations showed more profit potential than...

  20. A clinical study of fallopian tube recanalization by comptesswely injecting contrast medunm into the uterus

    International Nuclear Information System (INIS)

    Xi Jiayuan; Jiang Yong; Zhu Ying; Gong Hiafeng; Lv Liang; Zhao Xinxiang; Fang Min; Wei Dingying; Hua Jian

    2006-01-01

    Objective: To search for a new, simple, rapid, safe and effective method with combination of hystero. Salingography and fallopian tube recanalization. Methods: After the double-lumen balloon catheter was inserted into the uterine cavity and then followed by saline or air injection into to the saccule. The internal os of cervix was thus blocked by the filled saccule. Iohexol was injected into uterine cavity and fallopian tubes to undertake hystero-salingography and selective radiography under the television observation. In case of obstruction the fallopian tube recanalization could be obtained by manual increasing the contrast injection pressure into the uterine cavity. Results: 2698 cases including 811 primary infertile women and 1887 cases of secondary infertilities were examed by this method. The number of obstructed fallopian tube was 3082 including 1561 right fallopian tubes and 1521 left ones. The rate of tube obstruction was 77.77% and that of tube recanalization was 88.96% including 2397 branches recanalized completely and 322 partially recanalizd. The venous reflux was found in 27 cases and light complications included slight vagina bleeding, mild transient spastic pain without mortality. Conclusion: This method of combining hystero-salinography and fallopian tube recanalization, is safe, effective, economic and practical for infertile women with quick procedure process; and worthy to be recommended. (authors)

  1. Theoretical and experimental validation of evacuated tubes directly coupled with solar still

    Science.gov (United States)

    Panchal, H. N.; Thakkar, H.

    2016-11-01

    Experimental study of evacuated tubes coupled solar still in the climatic conditions of Mehsana, a region of North Gujarat, India during summer and winter climate conditions has been made. Experimental setup was made by authors. Fourteen double-walled hard borosilicate glass tubes have been used. Evacuated tubes were inclined at angle of 45° from horizontal. Outer tubes of evacuated tubes were transparent, inner tubes were coated with a selective coating of Al-Ni/Al compound for better solar radiation absorption and minimum emittance. It has been shown that evacuated tube attachments to the solar still increased the water temperature inside the solar still for increment in the generation of distillate output. Evacuated tubes coupled solar still is not only produce distilled water during sunshine hours, but also off-sunshine hours due to heat storage effect. For the validation of the experimental results, a theoretical model is proposed based on the fundamentals of heat and mass transfer equations for solar still glass cover, water in basin and basin bottom. Two main statistical parameters—root mean square error and mean bias error—were calculated to compare the results of experiments and theoretical analysis. Closed matching of the experimental and theoretical results has been found.

  2. A Study on the Development of Nonglass Solar Vacuum Tube Collector

    International Nuclear Information System (INIS)

    Oh, Seung Jin

    2008-02-01

    Nature has been providing us energy from the beginning of the world. However human has hardly used it wisely. Solar energy is a kind of renewable energy from the nature. This study has been carried out to study the use of solar energy as it is harnessed in the form of thermal energy. Solar energy is one of the most promising energy resources such as hydrogen, biomass, wind and geothermal energy, because it is clean and inexhaustible. Space heating in buildings can be provided from solar energy by systems that are similar in many respects to water heater systems. By tapping into solar energy, we can not only solve the problem of energy shortage, but also can protect the environment and benefit the human beings. There are currently two types of evacuated tube; a single glass tube and a double glass tube. The former consists of a single glass tube which contains a flat or curved aluminium plate attached to a copper heat pipe or water flow pipe. The latter consists of rows of parallel transparent glass tubes, each of which contains an absorber tube. Evacuated tube collectors introduced above, however, pose some problems as they break rather easily under mechanical stresses. This paper introduces some preliminary results in design and fabrication of a non-glass solar vacuum tube collector in which the thermosyphon(heat pipe)made of copper is used as a heat transfer device. A series of tests have been performed to assess the ability of a non-glass solar vacuum tube collector. The series of experiments are as follows: 1)Vacuum level inside a vacuum tube. 2)Effects of the air remaining inside a vacuum tube on the temperature on the absorber plate. 3)Comparison of a non-glass vacuum solar collector with a single glass evacuated tube(SEIDO 5). Different vacuum levels inside non-glass vacuum tubes were applied to check any leakage or unexpected physical or chemical developments with time. The vacuum level changed from 10 -2 torr to 5torr in 5 days due to air infiltration from

  3. Analysis of forming limit in tube hydroforming

    International Nuclear Information System (INIS)

    Kim, Chan Il; Yang, Seung Hang; Kim, Young Suk

    2013-01-01

    The automotive industry has shown increasing interest in tube hydroforming. Despite many automobile structural parts being produced from cylindrical tubes, failures frequently occur during tube hydroforming under improper forming conditions. These problems include wrinkling, buckling, folding back, and bursting. We perform analytical studies to determine forming limits in tube hydroforming and demonstrate how these forming limits are influenced by the loading path. Theoretical results for the forming limits of wrinkling and bursting are compared with experimental results for an aluminum tube.

  4. International double taxation

    OpenAIRE

    Odarčenko, Michal

    2015-01-01

    1 Summary This thesis deals with the issue of international double taxation of income and capital and methods for its solution. International double taxation is an issue which states began to deal with in the late 19th century. This interest intensified after the First World War when also the League of Nations (predecessor of the United Nations) began to deal with international double taxation. Most attention the phenomenon of double taxation of income and capital with an international elemen...

  5. The effectiveness of an endotracheal tube holder

    Directory of Open Access Journals (Sweden)

    Byung Gun Lim

    2016-01-01

    Full Text Available The security of the endotracheal tube (ETT is important in the anesthesia and intensive care settings. Recently, an ETT holder instead of an adhesive tape is frequently used to provide the fixation of the ETT. There are some studies that focused on the effectiveness of the ETT holder in preventing displacement of ETT compared to an adhesive tape (1, 2. I have experienced the use of an ETT holder (E-holder, KS medical, Bucheon, Korea in many different anesthesia settings and recognized its usefulness and convenience other than ETT security in the following specific settings.  Firstly, the ETT holder is definitely effective for patients undergoing procedures that frequently require the adjustment of ETT (or double lumen tube location including thoracic surgery. The location of double lumen tube needed for lung separation can be modified for effective ventilation during anesthetic induction or surgery, and after position changes. The tube can be easily relocated to the proper place for lung separation and effective ventilation by unlocking/relocking the button of the ETT holder under flexible bronchoscopic guidance (Fig. 1A, which can facilitate the operative procedure to be performed easily and quickly. Secondly, the ETT holder can be useful in procedures requiring the prone position (3. Especially, it is useful in all circumstances requiring the adjustment of ETT in the prone position. For instance, it is definitely useful for patients with Duchene muscular dystrophy undergoing scoliosis surgery under prone position. Adolescent patients with Duchene muscular dystrophy frequently have tracheobronchial malacia. If so, the airway pressure can be elevated due to the narrowing of the lesion of malacia when changed to the prone position (4. To overcome this problem, a reinforced ETT should be relocated so that it passes the narrowed tracheal lesion under flexible bronchoscopic guidance (Fig. 1B. However, the approach for this management is somewhat

  6. Physics of magnetic flux tubes

    CERN Document Server

    Ryutova, Margarita

    2015-01-01

    This book is the first account of the physics of magnetic flux tubes from their fundamental properties to collective phenomena in an ensembles of flux tubes. The physics of magnetic flux tubes is absolutely vital for understanding fundamental physical processes in the solar atmosphere shaped and governed by magnetic fields. High-resolution and high cadence observations from recent space and  ground-based instruments taken simultaneously at different heights and temperatures not only show the ubiquity of filamentary structure formation but also allow to study how various events are interconnected by system of magnetic flux tubes. The book covers both theory and observations. Theoretical models presented in analytical and phenomenological forms are tailored for practical applications. These are welded with state-of-the-art observations from early decisive ones to the most recent data that open a new phase-space for exploring the Sun and sun-like stars. Concept of magnetic flux tubes is central to various magn...

  7. Double Outlet Right Ventricle

    Science.gov (United States)

    ... Right Ventricle Menu Topics Topics FAQs Double Outlet Right Ventricle Double outlet right ventricle (DORV) is a rare form of congenital heart disease. Article Info En español Double outlet right ventricle (DORV) is a rare form of congenital ...

  8. Endotracheal tube defects: Hidden causes of airway obstruction

    Directory of Open Access Journals (Sweden)

    Sofi Khalid

    2010-01-01

    Full Text Available Manufacturing defects of endotracheal tube (ETT are still encountered in anesthesia practice. Many such defects go unnoticed during routine inspection prior to their use. Such defects in ETT may lead to partial or complete airway obstruction in an intubated patient. We report a case of partial airway obstruction with a prepacked, single use, uncuffed ETT due to a manufacturing defect in the form of a plastic meniscus at the distal end of the tube. This case report highlights the significance of standard monitoring of ventilation and the role of a vigilant clinician in detecting such defects in avoiding critical events as can arise from the use of such defective ETTs. It also emphasizes the need for double checking ETTs prior to their use.

  9. Study on high throughput nanomanufacturing of photopatternable nanofibers using tube nozzle electrospinning with multi-tubes and multi-nozzles

    Science.gov (United States)

    Fang, Sheng-Po; Jao, PitFee; Senior, David E.; Kim, Kyoung-Tae; Yoon, Yong-Kyu

    2017-12-01

    High throughput nanomanufacturing of photopatternable nanofibers and subsequent photopatterning is reported. For the production of high density nanofibers, the tube nozzle electrospinning (TNE) process has been used, where an array of micronozzles on the sidewall of a plastic tube are used as spinnerets. By increasing the density of nozzles, the electric fields of adjacent nozzles confine the cone of electrospinning and give a higher density of nanofibers. With TNE, higher density nozzles are easily achievable compared to metallic nozzles, e.g. an inter-nozzle distance as small as 0.5 cm and an average semi-vertical repulsion angle of 12.28° for 8-nozzles were achieved. Nanofiber diameter distribution, mass throughput rate, and growth rate of nanofiber stacks in different operating conditions and with different numbers of nozzles, such as 2, 4 and 8 nozzles, and scalability with single and double tube configurations are discussed. Nanofibers made of SU-8, photopatternable epoxy, have been collected to a thickness of over 80 μm in 240 s of electrospinning and the production rate of 0.75 g/h is achieved using the 2 tube 8 nozzle systems, followed by photolithographic micropatterning. TNE is scalable to a large number of nozzles, and offers high throughput production, plug and play capability with standard electrospinning equipment, and little waste of polymer.

  10. On hydraulics of capillary tubes

    Directory of Open Access Journals (Sweden)

    N.G. Aloyan

    2016-03-01

    Full Text Available The article considers the laws of motion of water in the capillary tubes, taken as a model for flowing well, on the analogical net count device. For capillary tube the lower limit value of flow rate is empirically determined above which the total hydraulic resistance of the capillary is practically constant. The specificity of the phenomenon is that the regime of motion, by a Reynolds number, for a given flow rate still remains laminar. This circumstance can perplex the specialists, so the author invites them to the scientific debate on the subject of study. Obviously, to identify the resulting puzzle it is necessary to conduct a series of experiments using capillaries of different lengths and diameters and with different values of overpressure. The article states that in tubes with very small diameter the preliminary magnitude of capillary rise of water in the presence of flow plays no role and can be neglected.

  11. Patient identification and tube labelling

    DEFF Research Database (Denmark)

    van Dongen-Lases, Edmée C; Cornes, Michael P; Grankvist, Kjell

    2016-01-01

    of phlebotomy procedures with the CLSI H3-A6 guideline was unacceptably low, and that patient identification and tube labelling are amongst the most critical steps in need of immediate attention and improvement. The process of patient identification and tube labelling is an essential safety barrier to prevent......Venous blood sampling (phlebotomy) is the most common invasive procedure performed in patient care. Guidelines on the correct practice of phlebotomy are available, including the H3-A6 guideline issued by the Clinical Laboratory Standards Institute (CLSI). As the quality of practices and procedures...... patient identity mix-up. Therefore, the EFLM Working Group aims to encourage and support worldwide harmonisation of patient identification and tube labelling procedures in order to reduce the risk of preanalytical errors and improve patient safety. With this Position paper we wish to raise awareness...

  12. Drift tubes of Linac 2

    CERN Multimedia

    CERN PhotoLab

    1977-01-01

    With the advent of the 800 MeV PS Booster in 1972, the original injector of the PS, a 50 MeV Alvarez-type proton linac, had reached its limits, in terms of intensity and stability. In 1973 one therefore decided to build a new linac (Linac 2), also with a drift-tube Alvarez structure and an energy of 50 MeV. It had a new Cockcroft-Walton preinjector with 750 keV, instead of the previous one with 500 keV. Linac 2 was put into service in 1980. The old Linac 1 was then used for the study of, and later operation with, various types of ions. This picture shows Linac 2 drift-tubes, suspended on stems coming from the top, in contrast to Linac 1, where the drift-tubes stood on stems coming from the bottom.

  13. Double layers in space

    International Nuclear Information System (INIS)

    Carlqvist, P.

    1982-01-01

    For more than a decade it has been realised that electrostatic double layers are likely to occur in space. The author briefly discusses the theoretical background of such double layers. Most of the paper is devoted to an account of the observational evidence for double layers in the ionosphere and magnetosphere of the Earth. Several different experiments are reviewed including rocket and satellite measurements and ground based observations. It is concluded that the observational evidence for double layers in space is very strong. The experimental results indicate that double layers with widely different properties may exist in space. (Auth.)

  14. Miniature X-Ray Tubes

    Science.gov (United States)

    Bearman, Gregory H.

    1995-01-01

    Miniature x-ray tubes proposed for use in portable instruments used to analyze minerals. Electrons from field emitter (instead of thermionic emitter) accelerated to target to generate x-rays. Fabricated from silicon wafers, micromachined field emitters (MFEs) not subject to breakage or restrictions on lifetimes, and tolerate vacuums that filaments cannot. Miniature x-ray tubes very robust, immune to shock and vibration, and permanently sealed with getter for continued pumping. Combined with solid-state x-ray detectors for analysis of x-ray fluorescence.

  15. Working session 3: Tubing integrity

    International Nuclear Information System (INIS)

    Cueto-Felgueroso, C.; Strosnider, J.

    1997-01-01

    Twenty-three individuals representing nine countries (Belgium, Canada, the Czech Republic, France, Japan, the Slovak Republic, Spain, the UK, and the US) participated in the session on tube integrity. These individuals represented utilities, vendors, consultants and regulatory authorities. The major subjects discussed by the group included overall objectives of managing steam generator tube degradation, necessary elements of a steam generator degradation management program, the concept of degradation specific management, structural integrity evaluations, leakage evaluations, and specific degradation mechanisms. The group's discussions on these subjects, including conclusions and recommendations, are summarized in this article

  16. Opposed slant tube diabatic sorber

    Science.gov (United States)

    Erickson, Donald C.

    2004-01-20

    A sorber comprised of at least three concentric coils of tubing contained in a shell with a flow path for liquid sorbent in one direction, a flow path for heat transfer fluid which is in counter-current heat exchange relationship with sorbent flow, a sorbate vapor port in communication with at least one of sorbent inlet or exit ports, wherein each coil is coiled in opposite direction to those coils adjoining it, whereby the opposed slant tube configuration is achieved, with structure for flow modification in the core space inside the innermost coil.

  17. YouTube and Facebook

    DEFF Research Database (Denmark)

    Robertson, Scott P.; Vatrapu, Ravi; Medina, Richard

    This paper examines the links to YouTube from the Facebook “walls” of Barack Obama, Hillary Clinton, and John McCain over two years prior to the 2008 U.S. Presidential election. User-generated linkage patterns show how participants in these politically-related social networking dialogues used...... online video to make their points. We show a strong integration of the Web 2.0 and new media technologies of social networking and online video. We argue that political discussion in social networking environments can no longer be viewed as primarily textual, and that neither Facebook nor YouTube can...

  18. Pump element for a tube pump

    DEFF Research Database (Denmark)

    2011-01-01

    The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction...... portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. The invention further relates to a pump element comprising at least two non-return valve members connected by a rod element, and for insertion in an at least partly flexible tube in such tube...... pump as mentioned above, thereby acting to generate a fluid flow through the tube upon repeated deformation of the tube between the two valve members. The pump element may comprise a connecting part for coupling to another tube and may comprise a sealing part establishing a fluid tight connection...

  19. Calcium-dependent protein kinases regulate polarized tip growth in pollen tubes.

    Science.gov (United States)

    Myers, Candace; Romanowsky, Shawn M; Barron, Yoshimi D; Garg, Shilpi; Azuse, Corinn L; Curran, Amy; Davis, Ryan M; Hatton, Jasmine; Harmon, Alice C; Harper, Jeffrey F

    2009-08-01

    Calcium signals are critical for the regulation of polarized growth in many eukaryotic cells, including pollen tubes and neurons. In plants, the regulatory pathways that code and decode Ca(2+) signals are poorly understood. In Arabidopsis thaliana, genetic evidence presented here indicates that pollen tube tip growth involves the redundant activity of two Ca(2+)-dependent protein kinases (CPKs), isoforms CPK17 and -34. Both isoforms appear to target to the plasma membrane, as shown by imaging of CPK17-yellow fluorescent protein (YFP) and CPK34-YFP in growing pollen tubes. Segregation analyses from two independent sets of T-DNA insertion mutants indicate that a double disruption of CPK17 and -34 results in an approximately 350-fold reduction in pollen transmission efficiency. The near sterile phenotype of homozygous double mutants could be rescued through pollen expression of a CPK34-YFP fusion. In contrast, a transgene rescue was blocked by mutations engineered to disrupt the Ca(2+)-activation mechanism of CPK34 (CPK34-YFP-E465A,E500A), providing in vivo evidence linking Ca(2+) activation to a biological function of a CPK. While double mutant pollen tubes displayed normal morphology, relative growth rates for the most rapidly growing tubes were reduced by more than three-fold compared with wild type. In addition, while most mutant tubes appeared to grow far enough to reach ovules, the vast majority (>90%) still failed to locate and fertilize ovules. Together, these results provide genetic evidence that CPKs are essential to pollen fitness, and support a mechanistic model in which CPK17 and -34 transduce Ca(2+) signals to increase the rate of pollen tube tip growth and facilitate a response to tropism cues.

  20. The beginning of a seed: regulatory mechanisms of double fertilization.

    Science.gov (United States)

    Bleckmann, Andrea; Alter, Svenja; Dresselhaus, Thomas

    2014-01-01

    THE LAUNCH OF SEED DEVELOPMENT IN FLOWERING PLANTS (ANGIOSPERMS) IS INITIATED BY THE PROCESS OF DOUBLE FERTILIZATION: two male gametes (sperm cells) fuse with two female gametes (egg and central cell) to form the precursor cells of the two major seed components, the embryo and endosperm, respectively. The immobile sperm cells are delivered by the pollen tube toward the ovule harboring the female gametophyte by species-specific pollen tube guidance and attraction mechanisms. After pollen tube burst inside the female gametophyte, the two sperm cells fuse with the egg and central cell initiating seed development. The fertilized central cell forms the endosperm while the fertilized egg cell, the zygote, will form the actual embryo and suspensor. The latter structure connects the embryo with the sporophytic maternal tissues of the developing seed. The underlying mechanisms of double fertilization are tightly regulated to ensure delivery of functional sperm cells and the formation of both, a functional zygote and endosperm. In this review we will discuss the current state of knowledge about the processes of directed pollen tube growth and its communication with the synergid cells resulting in pollen tube burst, the interaction of the four gametes leading to cell fusion and finally discuss mechanisms how flowering plants prevent multiple sperm cell entry (polyspermy) to maximize their reproductive success.

  1. The beginning of a seed: regulatory mechanisms of double fertilization

    Directory of Open Access Journals (Sweden)

    Andrea eBleckmann

    2014-09-01

    Full Text Available The launch of seed development in flowering plants (angiosperms is initiated by the process of double fertilization: two male gametes (sperm cells fuse with two female gametes (egg and central cell to form the precursor cells of the two major seed components, the embryo and endosperm, respectively. The immobile sperm cells are delivered by the pollen tube towards the ovule harboring the female gametophyte by species-specific pollen tube guidance and attraction mechanisms. After pollen tube burst inside the female gametophyte, the two sperm cells fuse with the egg and central cell initiating seed development. The fertilized central cell forms the endosperm while the fertilized egg cell, the zygote, will form the actual embryo and suspensor. The latter structure connects the embryo with the sporophytic maternal tissues of the developing seed. The underlying mechanisms of double fertilization are tightly regulated to ensure delivery of functional sperm cells and the formation of both, a functional zygote and endosperm. In this review we will discuss the current state of knowledge about the processes of directed pollen tube growth and its communication with the synergid cells resulting in pollen tube burst, the interaction of the four gametes leading to cell fusion and finally discuss mechanisms how flowering plants prevent multiple sperm cell entry (polyspermy to maximize their reproductive success.

  2. Study on antioxidant experiment on forged steel tube sheet and tube hole for steam generator

    International Nuclear Information System (INIS)

    Zong Hai; Wang Detai; Ding Yang

    2012-01-01

    Antioxidant experiment on forged steel tube sheet and tube hole for steam generator was studied and the influence of different simulated heat treatments on the antioxidant performance of tube sheet and tube hole was made. The influence of different antioxidant methods on the size of tube hole was drawn. Furthermore, the change of size and weight of 18MnD5 forged steel tube sheet on the condition of different simulated heat treatments was also studied. The analytical results have proved reference information for the use of 18MnD5 material and for key processes of processing tube hole and wearing and expanding U-style tube. (authors)

  3. Double-sided microtron at Nihon University

    International Nuclear Information System (INIS)

    Tanaka, T.; Hayakawa, K.; Yatoh, H.; Yoshida, K.; Takeda, O.; Sato, K.; Torizuka, Y.

    1990-01-01

    Construction of a 35 MeV cw double-sided microtron (DSM) at Nihon University was started in 1984 and completed in the spring of 1989. This machine was constructed as a proto-type of an 1 GeV cw double sided microtron for a medical pion facility and test accelerator for FEL and other applications. The 4.55 MeV electron beam from 5 MeV injector linac is injected to the DSM. The energy gain is 6 MeV at each turn acceleration. After recirculated 5 times, the electron beam with 34.5 MeV is extracted at the final short straight section. The DAW structure is used for all the accelerating tubes including the injector linac. Total rf power of 200 kW is provided by four 50 kW klystrons of 2450 MHz. (author)

  4. Mechanical support for straw tubes

    International Nuclear Information System (INIS)

    Joestlein, H.

    1990-01-01

    A design is proposed for mounting a large number of straw tubes to form an SSC central tracking chamber. The assembly is precise and of very low mass. The fabrication is modular and can be carried out with a minimum of tooling and instrumentation. Testing of modules is possible prior to the final assembly. 4 figs

  5. OurTube / David Talbot

    Index Scriptorium Estoniae

    Talbot, David

    2009-01-01

    USA California Ülikooli töötajate Abram Stern'i ja Michael Dale'i poolt 2005. a. algatatud USA kongressis peetud kõnede videoremiksidest ja nende poolt loodud veebisaidist Metavid.org. Ka YouTube keskkonnast ja wikipedia katsetustest muuta oma keskkond multimeedialisemaks

  6. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... Program Vision and Aging Program African American Program Training and Jobs Fellowships NEI Summer Intern Program Diversity In Vision Research & Ophthalmology (DIVRO) Student Training Programs To search for current job openings visit HHS USAJobs Home >> NEI YouTube Videos >> ...

  7. Working session 1: Tubing degradation

    International Nuclear Information System (INIS)

    Kharshafdjian, G.; Turluer, G.

    1997-01-01

    A general introductory overview of the purpose of the group and the general subject area of SG tubing degradation was given by the facilitator. The purpose of the session was described as to open-quotes develop conclusions and proposals on regulatory and technical needs required to deal with the issues of SG tubing degradation.close quotes Types, locations and characteristics of tubing degradation in steam generators were briefly reviewed. The well-known synergistic effects of materials, environment, and stress and strain/strain rate, subsequently referred to by the acronym open-quotes MESSclose quotes by some of the group members, were noted. The element of time (i.e., evolution of these variables with time) was emphasized. It was also suggested that the group might want to consider the related topics of inspection capabilities, operational variables, degradation remedies, and validity of test data, and some background information in these areas was provided. The presentation given by Peter Millet during the Plenary Session was reviewed; Specifically, the chemical aspects and the degradation from the secondary side of the steam generator were noted. The main issues discussed during the October 1995 EPRI meeting on secondary side corrosion were reported, and a listing of the potential SG tube degradations was provided and discussed

  8. Case of nasogastric tube dysfunction.

    Science.gov (United States)

    Rainer, Florian; Prenner, Guenther; Binder, Lukas Peter; Fickert, Peter; Plank, Johannes

    2018-01-05

    An elderly female patient was admitted to intensive care for prolonged vasopressor therapy and mechanical ventilation after cardiac arrest and acute percutaneous coronary intervention. Antiplatelet, thyroid hormone replacement and statin therapies were administered through a 14-French nasogastric tube (Nestlé Health Science) and enteral feeding was initiated. Correct position of the nasogastric tube was confirmed radiologically. On the seventh day in the intensive care, our patient was seen to regurgitate soft crumbs into her mouth. The blocked nasogastric tube was removed, but attempts to reinsert another tube failed.Upper GI endoscopy revealed an obstruction of the oesophagus with a milky-yellowish caseous substance 20 cm from the incisors (figure 1). The proximal part of the mass showed a central hole and ring-shaped layers resembling the cut face of a tree trunk.gutjnl;gutjnl-2017-315619v1/F1F1F1Figure 1Obstruction of the oesophagus with a milky-yellowish caseous substance. What caused the obstruction?How should we manage such a problem? © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. Kundt's Tube Experiment Using Smartphones

    Science.gov (United States)

    Parolin, Sara Orsola; Pezzi, Giovanni

    2015-01-01

    This article deals with a modern version of Kundt's tube experiment. Using economic instruments and a couple of smartphones, it is possible to "see" nodes and antinodes of standing acoustic waves in a column of vibrating air and to measure the speed of sound.

  10. Steam generator tube integrity program

    International Nuclear Information System (INIS)

    Diercks, D.R.; Shack, W.J.

    1996-01-01

    The degradation of steam generator tubes in pressurized water nuclear reactors continues to be a serious problem, and the US Nuclear Regulatory Commission (NRC) is developing a performance-based rule and regulatory guide for steam generator tube integrity. To support the evaluation of industry-proposed implementation of these performance-based criteria, the NRC is sponsoring a new research program at Argonne National Laboratory on steam generator tubing degradation. The objective of the new program is to provide the necessary experimental data and predictive correlations and models that will permit the NRC to independently evaluate the integrity of steam generator tubes. The technical work in the program is divided into four tasks, (1) assessment of inspection reliability, (2) research on in-service inspection technology, (3) research on degradation modes and integrity, and (4) development of methodology and technical assessments for current and emerging regulatory issues. The objectives of and planned research activities under each of these four tasks are described here. (orig.)

  11. Tube in shell heat exchangers

    International Nuclear Information System (INIS)

    Hayden, O.; Willby, C.R.; Sheward, G.E.; Ormrod, D.T.; Firth, G.F.

    1980-01-01

    An improved tube-in-shell heat exchanger to be used between liquid metal and water is described for use in the liquid metal coolant system of fast breeder reactors. It is stated that this design is less prone to failures which could result in sodium water reactions than previous exchangers. (UK)

  12. Tubing with high corrosion resistance

    Science.gov (United States)

    Ioffe, A. V.; Tetyueva, T. V.; Vyboyshchik, M. A.; Trifonova, E. A.; Lutsenko, E. S.

    2010-07-01

    The optimum chemical composition and the regime for heat treatment of heat-resistant steel 15Kh5M are determined for the production of tubing with strength of group L80 (API 5CT) and high cold resistance and resistance to carbon dioxide and sulfurated hydrogen corrosion at low alloying additives of chromium and molybdenum.

  13. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... Macular Degeneration Amblyopia Animations Blindness Cataract Convergence Insufficiency Diabetic Eye Disease Dilated Eye Exam Dry Eye For Kids Glaucoma Healthy Vision Tips Leber Congenital Amaurosis Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube ...

  14. Welding the CNGS decay tube

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    3.6 km of welds were required for the 1 km long CERN Neutrinos to Gran Sasso (CNGS) decay tube, in which particles produced in the collision with a proton and a graphite target will decay into muons and muon neutrinos. Four highly skilled welders performed this delicate task.

  15. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... and Aging Program African American Program Training and Jobs Fellowships NEI Summer Intern Program Diversity In Vision ... DIVRO) Student Training Programs To search for current job openings visit HHS USAJobs Home » NEI YouTube Videos » ...

  16. 21 CFR 876.5980 - Gastrointestinal tube and accessories.

    Science.gov (United States)

    2010-04-01

    ... intubation, feeding tube, gastroenterostomy tube, Levine tube, nasogastric tube, single lumen tube with... § 876.9. (2) Class I (general controls) for the dissolvable nasogastric feed tube guide for the nasogastric tube. The class I device is exempt from the premarket notification procedures in subpart E of part...

  17. Schizophrenia on YouTube.

    Science.gov (United States)

    Nour, Matthew M; Nour, Murraih H; Tsatalou, Olga-Maria; Barrera, Alvaro

    2017-01-01

    YouTube ( www.youtube.com ) is the most popular video-sharing Web site on the Internet and is used by medical students as a source of information regarding mental health conditions, including schizophrenia. The accuracy and educational utility of schizophrenia presentations on YouTube are unknown. The purpose of this study was to analyze the accuracy of depictions of psychosis in the context of a diagnosis of schizophrenia (referred to in this article as "acute schizophrenia") on YouTube and to assess the utility of these videos as educational tools for teaching medical students to recognize the clinical features of acute schizophrenia. YouTube was searched for videos purporting to show acute schizophrenia. Eligible videos were independently rated by two consultant psychiatrists on two separate occasions 22 days apart for diagnostic accuracy, psychopathology, and educational utility. Videos (N=4,200) were assessed against predefined inclusion and exclusion criteria. The majority were not eligible for further analysis, mostly because they did not claim to show a patient with schizophrenia (74%) or contained duplicated content (11%). Of 35 videos that met the eligibility and adequacy criteria, only 12 accurately depicted acute schizophrenia. Accurate videos were characterized by persecutory delusions (83%), inappropriate affect (75%), and negative symptoms (83%). Despite the fact that 83% of accurate videos were deemed to have good educational utility compared with 15% of inaccurate videos, accurate and inaccurate videos had similar view counts (290,048 versus 186,124). Schizophrenia presentations on YouTube offer a distorted picture of the condition.

  18. Preparation of metallic uranium tubes

    International Nuclear Information System (INIS)

    Lerouge, G.; Decours, J.

    1964-01-01

    The production furnace is an induction heated vacuum furnace having a capacity at the moment of 250 kg. Previously the crucible was heated by the inductor, the mould being outside the inductor. The tubes thus produced contained cavities, the alloy structure was fine; this was cold-mould casting, At the moment the top of the moulds are pre-heated, this is the so called hot-mould casting. This method has the advantage of eliminating the cavities but leads to a less fine microstructure. The alloy used for the 18 x 40 mm and 23 x 43 mm tubes is U-Mo (1.1 per cent). Since the moulds are now heated at the top, the solidification of the metal is very slow in this zone leading to a pronounced γ grain, whereas towards the base the faster cooling leads to a smaller γ grain. The γ structure depends essentially on the solidification rate and on the time spent in this zone. In order to obtain a fine and homogeneous grain along the whole length of the tube, a controlled cooling treatment is effected. It consists in heating the uranium tubes in the γ place and then in cooling them at a rate of between 20 and 50 deg C/mm down to 400 deg C. The 77 x 95 mm and 54 x 70 mm annular elements are at the moment being produced for research purposes. Their preparation is similar to that of 18 x 40 mm and 23 x 43 mm elements. The 77 x 95 mm tubes are at the moment made from U-Cr alloy (0.1 per cent); because of their size, their preparation is carried out in 600 mm diameter furnaces. (authors) [fr

  19. Rejection index for pressure tubes

    International Nuclear Information System (INIS)

    Mitchell, A.B.; Meneley, D.

    1989-10-01

    The objective of the present study was to establish a set of criteria (or Rejection Index) which could be used to decide whether a zirconium-2 1/2 w/o niobium pressure tube in a CANDU reactor should be removed from service due to in-service degradation. A critique of key issues associated with establishing a realistic rejection index was prepared. Areas of uncertainty in available information were identified and recommendations for further analysis and laboratory testing made. A Rejection Index based on the following limits has been recommended: 1) Limits related to design intent and normal operation: any garter spring must remain within the tolerance band specified for its design location; the annulus gas system must normally be operated in a circulating mode with a procedure in place for purging to prevent accumulation of deuterium. It must remain sensitive to leaks into any part of the systems; and pressure tube dimensions and distortions must be limited to maintain the fuel channels within the original design intent; 2) Limits related to defect tolerance: adequate time margins between occurrence of a leaking crack and unstable failure must be demonstrated for all fuel channels; long lap-type flaws are unacceptable; crack-like defects of any size are unacceptable; and score marks, frat marks and other defects with contoured profiles must fall below certain depth, length and stress intensity limits; and 3) Limits related to property degradation: at operating temperature each pressure tube must be demonstrated to have a critical length in excess of a stipulated value; the maximum equivalent hydrogen level in any pressure tube should not exceed a limit which should be defined taking into account the known history of that tube; the maximum equivalent hydrogen level in any rolled joint should not exceed a limit which is presently recommended as 200 ppm equivalent hydrogen; and the maximum diametral creep strain should be limited to less than 5%

  20. Improving the calandria tubes for CANDU reactors

    International Nuclear Information System (INIS)

    Coleman, C.E.; Fong, R.W.L.; Doubt, G.L.

    1997-01-01

    CANDU calandria tubes are made from annealed Zircaloy-2 sheet formed into a cylinder and welded along its length to make the tube. The current calandria tubes have given exemplary service for many years. With more stringent regulations and the need to accommodate warm cooling water in tropical countries, we started a development program to increase the margins for failure during postulated accidents. These improvements involve increasing the tube strength and optimising the heat-transfer from an excessively hot fuel channel to the cool moderator. If the postulated accident involves a pressure tube break, it would be desirable if the calandria tube withstood the full pressure of the heat-transport system. The weakest link in current calandria tubes is the weld. Thickening the weld can increase the strength by 20% while seamless tubes can be 45% stronger than current tubes. The latter tubes can hold full system pressure for many hours without failure. If during the postulated accident the fuel and pressure tube become excessively hot but do not touch the calandria tube, the radiant heat loss must be maximised. Current calandria tubes have an absorptivity (emissivity) of about 0.2. To protect the fuel and the fuel channel we have devised a finish to the inside surface of the calandria tube that increases the emissivity to 0.7. If during the postulated accident the hot pressure tube touches the cool calandria tube, the contact conductance and the critical heat flux must be optimised to ensure nucleate boiling of the moderator at the outside surface of the calandria tube and therefore efficient exploitation of the moderator as a heat sink. In laboratory tests small ridges on the inside surface and roughening of the outside surface have been shown to increase the margins against failure and increase the possible moderator temperatures thus providing the opportunity to decrease the cost of the moderator heat-exchange system and remove restrictions on reactor operation in

  1. A case of a 'lost' nasogastric tube.

    Science.gov (United States)

    Sankar, V; Shakeel, M; Keh, S; Ah-See, K W

    2012-12-01

    To present the case of a 'lost' nasogastric tube and to highlight the importance of imaging and/or chest X-ray after nasogastric tube insertion, especially in unreliable patients. A 50-year-old man, undergoing radiotherapy treatment for squamous cell carcinoma of the tongue base, was admitted for pain control and nasogastric tube feeding. This patient required multiple nasogastric tubes over a two-week period. The patient repeatedly denied pulling the nasogastric tube out and we were unable to establish the exact mode of nasogastric tube removal. On one such occasion another tube was inserted and a check X-ray showed two feeding tubes; the latest one was lying in the left main bronchus and the old nasogastric tube was observed in the oesophagus, with its upper end jutting above the hypopharynx. It was apparent that the patient had somehow cut the tube and swallowed it. This case not only illustrates the importance of flexible nasendoscopy and/or chest X-ray for checking the position of the nasogastric tube, but also highlights that some patients are not tolerant of nasogastric tubes. The use of nasogastric tubes should be avoided in these patients to prevent any self-inflicted injury.

  2. [Tracheal intubation with Parker Flex-Tip tubes assisted by tube-guiding devices].

    Science.gov (United States)

    Mizuno, Ju; Morita, Shigeho; Suzuki, Maya; Arita, Hideko; Hanaoka, Kazuo

    2010-04-01

    In tracheal intubation assisted by tube-guiding devices passing through the tube, such as fiberoptic scopes, bougies, tracheal tube exchange catheters, and light wands, passage of the tube-guiding device, by itself, is often easy. But advancing a tracheal tube with a conventional distal tip over these tube-guiding devices is frequently difficult or impossible, because its rigid, side-beveled tip frequently catches on anatomical features of the airway. A novel tracheal tube, the Parker Flex-Tip tube (Parker Medical, Colorado, USA) has a centered, curved, tapered and flexible distal tip that passes through the airway faster and easier than conventional tracheal tubes. As it is advanced along a tube-guiding device, the tip of the Parker tube travels along the midline of the airway, without the gap that usually exists between the distal edge of a conventional tracheal tube and the tube-guiding device. The gapless, midline travel of the Parker tube leads to a greater incidence of first-attempt intubation success with tube-guiding devices, because there is less risk of tube tip hang-ups on the arytenoids and the vocal cords. Clinically, use of the Parker tube is helpful for oral and nasal intubations, especially in patients with difficult airways.

  3. Outcomes of Infants with Home Tube Feeding: Comparing Nasogastric Versus Gastrostomy Tubes

    Science.gov (United States)

    Khalil, Syed Tariq; Uhing, Michael R.; Duesing, Lori; Visotcky, Alexis; Tarima, Sergey; Nghiem-Rao, T. Hang

    2017-01-01

    Background Determine the tube-related complications and feeding outcomes of infants discharged home from the NICU with nasogastric (NG) tube feeding or gastrostomy (G-tube) feeding. Material & Methods We performed a chart review of 335 infants discharged from our NICU with home NG tube or G-tube feeding between January 2009 – December 2013. The primary outcome was the incidence of feeding tube-related complications requiring emergency department (ED) visits, hospitalizations, or deaths. Secondary outcome was feeding status at 6 months post-discharge. Univariate and multivariate analyses were conducted. Results There were 322 infants discharged with home enteral tube feeding, 84 NG tube and 238 G-tube, with available out-patient data for the 6 month post-discharge period. A total of 115 ED visits, 28 hospitalizations, and 2 deaths were due to a tube-related complication. The incidence of tube-related complications requiring an ED visit was significantly higher in the G-tube group compared to the NG tube group (33.6% vs 9.5%, p tube related complication. By 6 months post-discharge, full oral feeding was achieved in 71.4% of infants in the NG tube group compared to 19.3% in the G-tube group (p tube and percentage of oral feeding at discharge were significantly associated with continued tube feeding at 6 months post-discharge. Conclusion Home NG tube feeding is associated with fewer ED visits for tube-related complications compared to home G-tube feeding. There may be some infants who could benefit from a trial home NG tube feeding. PMID:27647478

  4. Outcomes of Infants With Home Tube Feeding: Comparing Nasogastric vs Gastrostomy Tubes.

    Science.gov (United States)

    Khalil, Syed Tariq; Uhing, Michael R; Duesing, Lori; Visotcky, Alexis; Tarima, Sergey; Nghiem-Rao, T Hang

    2017-11-01

    The aim of this study was to determine the tube-related complications and feeding outcomes of infants discharged home from the neonatal intensive care unit (NICU) with nasogastric (NG) tube feeding or gastrostomy (G-tube) feeding. We performed a chart review of 335 infants discharged from our NICU with home NG tube or G-tube feeding between January 2009 and December 2013. The primary outcome was the incidence of feeding tube-related complications requiring emergency department (ED) visits, hospitalizations, or deaths. Secondary outcome was feeding status at 6 months postdischarge. Univariate and multivariate analyses were conducted. There were 322 infants discharged with home enteral tube feeding (NG tube, n = 84; G-tube, n = 238), with available outpatient data for the 6-month postdischarge period. A total of 115 ED visits, 28 hospitalizations, and 2 deaths were due to a tube-related complication. The incidence of tube-related complications requiring an ED visit was significantly higher in the G-tube group compared with the NG tube group (33.6% vs 9.5%, P tube-related complication. By 6 months postdischarge, full oral feeding was achieved in 71.4% of infants in the NG tube group compared with 19.3% in the G-tube group ( P tube and percentage of oral feeding at discharge were significantly associated with continued tube feeding at 6 months postdischarge. Home NG tube feeding is associated with fewer ED visits for tube-related complications compared with home G-tube feeding. Some infants could benefit from a trial home NG tube feeding.

  5. In service inspection for steam generator tubes

    International Nuclear Information System (INIS)

    Comby, R.; Eyrolles, Ph.

    1988-01-01

    In this paper the authors show the means putting in place for examination of steam generators tubes. These means (eddy current probes, ultrasonic testing) associated with a knowledge on degradation phenomena allow mapping controlled tubes and limiting undesirable obturations [fr

  6. X-ray tube current control

    International Nuclear Information System (INIS)

    Dupuis, W.A.; Resnick, T.A.

    1982-01-01

    A closed loop feedback system for controlling the current output of an x-ray tube. The system has circuitry for improving the transient response and stability of the x-ray tube current over a substantial nonlinear portion of the tube current production characteristic. The system includes a reference generator for applying adjustable step function reference signals representing desired tube currents. The system also includes means for instantaneous sensing of actual tube current. An error detector compares the value of actual and reference tube current and produces an error signal as a function of their difference. The system feedback loop includes amplification circuitry for controlling x-ray tube filament dc voltage to regulate tube current as a function of the error signal value. The system also includes compensation circuitry, between the reference generator and the amplification circuitry, to vary the loop gain of the feedback control system as a function of the reference magnitude

  7. The accessory fallopian tube: A rare anomaly

    Directory of Open Access Journals (Sweden)

    Kusum R Gandhi

    2012-01-01

    Full Text Available This paper presents a rare anatomical variation in the form of accessory fallopian tube on right side. The duplication of fallopian tube was observed in a 34-year-old female during routine undergraduate dissection in our department. Fallopian tube is the part of uterus that carries the ovum from the ovary to the uterus. Accessory fallopian tube is the congenital anomaly attached to the ampullary part of main tube. This accessory tube is common site of pyosalpinx, hydrosalpinx, cystic swelling and torsion. The ovum released by the ovary may also be captured by the blind accessory tube leading to infertility or ectopic pregnancy. Hence, all patients of infertility or pelvic inflammatory disease should be screened to rule out the presence of accessory fallopian tube and if encountered should be removed.

  8. Chemical cleaning specification: few tube test model

    International Nuclear Information System (INIS)

    Hampton, L.V.; Simpson, J.L.

    1979-09-01

    The specification is for the waterside chemical cleaning of the 2 1/4 Cr - 1 Mo steel steam generator tubes. It describes the reagents and conditions for post-chemical cleaning passivation of the evaporator tubes

  9. Prestressed Carbon Fiber Composite Overwrapped Gun Tube

    National Research Council Canada - National Science Library

    Littlefield, Andrew; Hyland, Edward

    2006-01-01

    .... Using composite materials not only directly removes weight from the gun tube but, by better balancing the tube, allows the use of smaller drive systems, thus further enhancing the system weight loss...

  10. Ceramic vacuum tubes for geothermal well logging

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, R.D.

    1977-01-01

    Useful design data acquired in the evaluation of ceramic vacuum tubes for the development of a 500/sup 0/C instrumentation amplifier are presented. The general requirements for ceramic vacuum tubes are discussed for application to the development of high temperature well logs. Commercially available tubes are described and future contract activities that specifically relate to ceramic vacuum tubes are detailed. Supplemental data are presented in the appendix.

  11. Overlapping double potential wells in a single optical microtube cavity with vernier-scale-like tuning effect

    Energy Technology Data Exchange (ETDEWEB)

    Madani, A.; Schmidt, O. G. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany); Material Systems for Nanoelectronics, Chemnitz University of Technology, Reichenhainer Str. 70, 09107 Chemnitz (Germany); Bolaños Quiñones, V. A.; Ma, L. B., E-mail: l.ma@ifw-dresden.de; Jorgensen, M. R. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany); Miao, S. D. [Anhui Key Lab of Controllable Chemical Reaction and Material Chemical Engineering, School of Chemical Engineering, Hefei University of Technology, Tunxi Road. 193, Hefei, Anhui 230009 (China)

    2016-04-25

    Spatially and temporally overlapping double potential wells are realized in a hybrid optical microtube cavity due to the coexistence of an aggregate of luminescent quantum dots embedded in the tube wall and the cone-shaped tube's geometry. The double potential wells produce two independent sets of optical modes with different sets of mode numbers, indicating phase velocity separation for the modes overlapping at the same frequency. The overlapping mode position can be tuned by modifying the tube cavity, where these mode sets shift with different magnitudes, allowing for a vernier-scale-like tuning effect.

  12. Spring/dimple instrument tube restraint

    Science.gov (United States)

    DeMario, E.E.; Lawson, C.N.

    1993-11-23

    A nuclear fuel assembly for a pressurized water nuclear reactor has a spring and dimple structure formed in a non-radioactive insert tube placed in the top of a sensor receiving instrumentation tube thimble disposed in the fuel assembly and attached at a top nozzle, a bottom nozzle, and intermediate grids. The instrumentation tube thimble is open at the top, where the sensor or its connection extends through the cooling water for coupling to a sensor signal processor. The spring and dimple insert tube is mounted within the instrumentation tube thimble and extends downwardly adjacent the top. The springs and dimples restrain the sensor and its connections against lateral displacement causing impact with the instrumentation tube thimble due to the strong axial flow of cooling water. The instrumentation tube has a stainless steel outer sleeve and a zirconium alloy inner sleeve below the insert tube adjacent the top. The insert tube is relatively non-radioactivated inconel alloy. The opposed springs and dimples are formed on diametrically opposite inner walls of the insert tube, the springs being formed as spaced axial cuts in the insert tube, with a web of the insert tube between the cuts bowed radially inwardly for forming the spring, and the dimples being formed as radially inward protrusions opposed to the springs. 7 figures.

  13. Manual tube-to-tubesheet welding torch

    Science.gov (United States)

    Kiefer, Joseph H.; Smith, Danny J.

    1982-01-01

    A welding torch made of a high temperature plastic which fits over a tube intermediate the ends thereof for welding the juncture between the tube and the back side of a tube plate and has a ballooned end in which an electrode, filler wire guide, fiber optic bundle, and blanketing gas duct are disposed.

  14. Heat exchanger with a removable tube section

    Science.gov (United States)

    Wolowodiuk, W.; Anelli, J.

    1975-07-29

    A heat exchanger is described in which the tube sheet is secured against primary liquid pressure, but which allows for easy removal of the tube section. The tube section is supported by a flange which is secured by a number of shear blocks, each of which extends into a slot which is immovable with respect to the outer shell of the heat exchanger. (auth)

  15. The Fuge Tube Diode Array Spectrophotometer

    Science.gov (United States)

    Arneson, B. T.; Long, S. R.; Stewart, K. K.; Lagowski, J. J.

    2008-01-01

    We present the details for adapting a diode array UV-vis spectrophotometer to incorporate the use of polypropylene microcentrifuge tubes--fuge tubes--as cuvettes. Optical data are presented validating that the polyethylene fuge tubes are equivalent to the standard square cross section polystyrene or glass cuvettes generally used in…

  16. Feasibility study of aluminum beam tube for the collider: An option for no-coating and no-liner

    International Nuclear Information System (INIS)

    Chou, W.

    1994-07-01

    This report proposes to use a single-layer beam tube made of high strength, high resistivity aluminum alloy (such as 7039-T61 or A7N01) to replace the double-layer copper coated stainless steel tube in the SSC Collider. The main reasons are: (1) a potential saving of about $23 million which is basically the baseline cost of the copper coating and (2) the use of an extruded aluminum tube consisting of a beam chamber and a pumping chamber may solve the vacuum problem without any liner

  17. THE EFFECTS OF SWIRL GENERATOR HAVING WINGS WITH HOLES ON HEAT TRANSFER AND PRESSURE DROP IN TUBE HEAT EXCHANGER

    Directory of Open Access Journals (Sweden)

    Zeki ARGUNHAN

    2006-02-01

    Full Text Available This paper examines the effect of turbulance creators on heat transfer and pressure drop used in concentric heat exchanger experimentaly. Heat exchanger has an inlet tube with 60 mm in diameter. The angle of swirl generators wings is 55º with each wing which has single, double, three and four holes. Swirl generators is designed to easily set to heat exchanger entrance. Air is passing through inner tube of heat exhanger as hot fluid and water is passing outer of inner tube as cool fluid.

  18. Numerical and experimental study of an annular pulse tube used in the pulse tube cooler

    Science.gov (United States)

    Pang, Xiaomin; Chen, Yanyan; Wang, Xiaotao; Dai, Wei; Luo, Ercang

    2017-12-01

    Multi-stage pulse tube coolers normally use a U-type configuration. For compactness, it is attractive to build a completely co-axial multi-stage pulse tube cooler. In this way, an annular shape pulse tube is inevitable. Although there are a few reports about previous annular pulse tubes, a detailed study and comparison with a circular pulse tube is lacking. In this paper, a numeric model based on CFD software is carried out to compare the annular pulse tube and circular pulse tube used in a single stage in-line type pulse tube cooler with about 10 W of cooling power at 77 K. The length and cross sectional area of the two pulse tubes are kept the same. Simulation results show that the enthalpy flow in the annular pulse tube is lower by 1.6 W (about 11% of the enthalpy flow) compared to that in circular pulse tube. Flow and temperature distribution characteristics are also analyzed in detail. Experiments are then conducted for comparison with an in-line type pulse tube cooler. With the same acoustic power input, the pulse tube cooler with a circular pulse tube obtains 7.88 W of cooling power at 77 K, while using an annular pulse tube leads to a cooling power of 7.01 W, a decrease of 0.9 W (11.4%) on the cooling performance. The study sets the basis for building a completely co-axial two-stage pulse tube cooler.

  19. Morphomechanics: transforming tubes into organs.

    Science.gov (United States)

    Taber, Larry A

    2014-08-01

    After decades focusing on the molecular and genetic aspects of organogenesis, researchers are showing renewed interest in the physical mechanisms that create organs. This review deals with the mechanical processes involved in constructing the heart and brain, concentrating primarily on cardiac looping, shaping of the primitive brain tube, and folding of the cerebral cortex. Recent studies suggest that differential growth drives large-scale shape changes in all three problems, causing the heart and brain tubes to bend and the cerebral cortex to buckle. Relatively local changes in form involve other mechanisms such as differential contraction. Understanding the mechanics of organogenesis is central to determining the link between genetics and the biophysical creation of form and structure. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Microwave discharges in capillary tubes

    International Nuclear Information System (INIS)

    Dervisevic, Emil

    1984-01-01

    This research thesis aims at being a contribution to the study of microwave discharge by a surface wave, and more precisely focusses on the discharge in capillary tubes filled with argon. The author first present theoretical models which describe, on the one hand, the propagation of the surface wave along the plasma column, and, on the other hand, longitudinal and radial profiles of the main discharge characteristics. The second part addresses the study of the influence of parameters (gas pressure and tube radius) on discharge operation and characteristics. Laws of similitude as well as empirical relationships between argon I and argon II emission line intensities, electron density, and electric field in the plasma have been established [fr

  1. Scintillation counter: photomultiplier tube alignment

    International Nuclear Information System (INIS)

    Olson, R.E.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into the sample receiving zone. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (auth)

  2. Ionization tube simmer current circuit

    Science.gov (United States)

    Steinkraus, R.F. Jr.

    1994-12-13

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current. 6 figures.

  3. ATLAS Muon Drift Tube Electronics

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Y [KEK, High Energy Accelerator Research Organisation, Tsukuba (Japan); Ball, B; Chapman, J W; Dai, T; Ferretti, C; Gregory, J [University of Michigan, Department of Physics, Ann Arbor, MI (United States); Beretta, M [INFN Laboratori Nazionali di Frascati, Frascati (Italy); Boterenbrood, H; Jansweijer, P P M [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Brandenburg, G W; Fries, T; Costa, J Guimaraes da; Harder, S; Huth, J [Harvard University, Laboratory for Particle Physics and Cosmology, Cambridge, MA (United States); Ceradini, F [INFN Roma Tre and Universita Roma Tre, Dipartimento di Fisica, Roma (Italy); Hazen, E [Boston University, Physics Department, Boston, MA (United States); Kirsch, L E [Brandeis University, Department of Physics, Waltham, MA (United States); Koenig, A C [Radboud University Nijmegen/Nikhef, Dept. of Exp. High Energy Physics, Nijmegen (Netherlands); Lanza, A [INFN Pavia, Pavia (Italy); Mikenberg, G [Weizmann Institute of Science, Department of Particle Physics, Rehovot (Israel)], E-mail: brandenburg@physics.harvard.edu (and others)

    2008-09-15

    This paper describes the electronics used for the ATLAS monitored drift tube (MDT) chambers. These chambers are the main component of the precision tracking system in the ATLAS muon spectrometer. The MDT detector system consists of 1,150 chambers containing a total of 354,000 drift tubes. It is capable of measuring the sagitta of muon tracks to an accuracy of 60 {mu}m, which corresponds to a momentum accuracy of about 10% at p{sub T}= 1 TeV. The design and performance of the MDT readout electronics as well as the electronics for controlling, monitoring and powering the detector will be discussed. These electronics have been extensively tested under simulated running conditions and have undergone radiation testing certifying them for more than 10 years of LHC operation. They are now installed on the ATLAS detector and are operating during cosmic ray commissioning runs.

  4. ATLAS Muon Drift Tube Electronics

    CERN Document Server

    Arai, Y; Beretta, M; Boterenbrood, H; Brandenburg, G W; Ceradini, F; Chapman, J W; Dai, T; Ferretti, C; Fries, T; Gregory, J; Guimarães da Costa, J; Harder, S; Hazen, E; Huth, J; Jansweijer, P P M; Kirsch, L E; König, A C; Lanza, A; Mikenberg, G; Oliver, J; Posch, C; Richter, R; Riegler, W; Spiriti, E; Taylor, F E; Vermeulen, J; Wadsworth, B; Wijnen, T A M

    2008-01-01

    This paper describes the electronics used for the ATLAS monitored drift tube (MDT) chambers. These chambers are the main component of the precision tracking system in the ATLAS muon spectrometer. The MDT detector system consists of 1,150 chambers containing a total of 354,000 drift tubes. It is capable of measuring the sagitta of muon tracks to an accuracy of 60 microns, which corresponds to a momentum accuracy of about 10% at pT = 1 TeV. The design and performance of the MDT readout electronics as well as the electronics for controlling, monitoring and powering the detector will be discussed. These electronics have been extensively tested under simulated running conditions and have undergone radiation testing certifying them for more than 10 years of LHC operation. They are now installed on the ATLAS detector and are operating during cosmic ray commissioning runs.

  5. Origami interleaved tube cellular materials

    International Nuclear Information System (INIS)

    Cheung, Kenneth C; Tachi, Tomohiro; Calisch, Sam; Miura, Koryo

    2014-01-01

    A novel origami cellular material based on a deployable cellular origami structure is described. The structure is bi-directionally flat-foldable in two orthogonal (x and y) directions and is relatively stiff in the third orthogonal (z) direction. While such mechanical orthotropicity is well known in cellular materials with extruded two dimensional geometry, the interleaved tube geometry presented here consists of two orthogonal axes of interleaved tubes with high interfacial surface area and relative volume that changes with fold-state. In addition, the foldability still allows for fabrication by a flat lamination process, similar to methods used for conventional expanded two dimensional cellular materials. This article presents the geometric characteristics of the structure together with corresponding kinematic and mechanical modeling, explaining the orthotropic elastic behavior of the structure with classical dimensional scaling analysis. (paper)

  6. X-ray tube target

    International Nuclear Information System (INIS)

    Weber, R.G.

    1980-01-01

    A target with an improved heat emissive surface for use in a rotating anode type x-ray tube is described. The target consists of a body having a first surface portion made of x-ray emissive material and a second surface portion made of a heat emissive material comprising at least one of hafnium boride, hafnium oxide, hafnium nitride, hafnium silicide, and hafnium aluminide. (U.K.)

  7. The comparison of corrosion resistance between Baosteel's alloy 690 tube and foreign alloy 690 tube

    International Nuclear Information System (INIS)

    Ma Mingjuan; Zhang Lefu; Li Yan

    2012-01-01

    Alloy 690 having excellent corrosion resistance is widely used for SG tubes. The intergranular corrosion and pitting corrosion resistance of Baosteel's alloy 690 tube, Country A alloy 690 tube and Country B alloy 690 tube have been analysed by comparison. It shows that: The intergranular corrosion of Baosteel's alloy 690 tube tested complied with ASTM G28 Standard could satisfy the technical requirement. However.some of Baosteel's alloy 690 tube in intergranular corrosion resistance had less performance than Country A. In addition, pitting corrosion tested with ASTM G48 Standard shown the Baosteel's alloy 690 tube better than Country B. (authors)

  8. Dynamic characteristics of heat exchanger tubes vibrating in a tube support plate inactive mode

    International Nuclear Information System (INIS)

    Jendrzejczyk, J.A.

    1985-01-01

    Tubes in shell-and-tube heat exchangers, including nuclear plant steam generators, derive their support from longitudinally positioned tube support plates (TSPs). Typically there is a clearance between the tube and TSP hole. Depending on design and fabrication tolerances, the tube may or may not contact all of the TSPs. Noncontact results in an inactive TSP which can lead to detrimental flow induced tube vibrations under certain conditions dependent on the resulting tube-TSP interaction dynamics and the fluid excitation forces. The purpose of this study is to investigate the tube-TSP interaction dynamics. Results of an experimental study of damping and natural frequency as functions of tube-TSP diametral clearance and TSP thickness are reported. Calculated values of damping ratio and frequency of a tube vibrating within an inactive TSP are also presented together with a comparison of calculated and experimetnal quantities

  9. Advanced pressure tube sampling tools

    International Nuclear Information System (INIS)

    Wittich, K.C.; King, J.M.

    2002-01-01

    Deuterium concentration is an important parameter that must be assessed to evaluate the Fitness for service of CANDU pressure tubes. In-reactor pressure tube sampling allows accurate deuterium concentration assessment to be made without the expenses associated with fuel channel removal. This technology, which AECL has developed over the past fifteen years, has become the standard method for deuterium concentration assessment. AECL is developing a multi-head tool that would reduce in-reactor handling overhead by allowing one tool to sequentially sample at all four axial pressure tube locations before removal from the reactor. Four sets of independent cutting heads, like those on the existing sampling tools, facilitate this incorporating proven technology demonstrated in over 1400 in-reactor samples taken to date. The multi-head tool is delivered by AECL's Advanced Delivery Machine or other similar delivery machines. Further, AECL has developed an automated sample handling system that receives and processes the tool once out of the reactor. This system retrieves samples from the tool, dries, weighs and places them in labelled vials which are then directed into shielded shipping flasks. The multi-head wet sampling tool and the automated sample handling system are based on proven technology and offer continued savings and dose reduction to utilities in a competitive electricity market. (author)

  10. Double deflation and aggregation

    NARCIS (Netherlands)

    Dietzenbacher, Erik; Hoen, A.R.

    Published input-output tables in constant prices are relatively scarce. Therefore, input-output tables often have to be deflated by the practitioners themselves. The method of double deflation is used predominantly for this purpose. The present paper shows that the double-deflation method is subject

  11. Double layer formation

    International Nuclear Information System (INIS)

    Singh, N.

    1982-01-01

    Results from several numerical simulations of the formation of double layers in plasmas with a constant potential drop across them are presented. Here the emphasis is mainly on plasma processes during the formation of double layers. The recurring formation of double layers, their propagation and associated current interruptions are observed when the electron current injected into the simulation region from the low potential side exceeds the electron thermal current. This recurring process is stopped (or delayed) when the electron current recuperation is inhibited by a small magnetic force on the electrons. The motion of double layers is examined and it is found that the motion is caused by the interruption of the ion current from the high potential side. The subsequent recovery of this current renders the double layer stationary. (author)

  12. Tube entrance lens focus control

    Science.gov (United States)

    Weisser, D. C.; Fifield, L. K.; Kitchen, T. F. G.; Tunningley, T. B.; Lobanov, N. R.; Muirhead, A. G.

    2013-02-01

    The entrance of the accelerator tube in a large electrostatic accelerator imposes a strong lens that dominates the beam optics. The magnification of the lens is large because of the low injection energy, the high voltage gradient of the acceleration tube and the long distance to the terminal. In the absence of the acceleration, the magnification would produce an unacceptably large beam spot at the terminal. The tyranny of the lens is especially irksome when the accelerator is required to operate at a lower terminal voltage than the one corresponding to the nominal gradient at high voltage. One way around the difficulty, used in NEC Pelletron accelerators, is to insert a series of nylon and steel rods that short together units of the acceleration structure at the terminal leaving the ones near the entrance close to the nominal gradient for optimum transmission. This operation takes time and risks the loss of insulating gas. Another alternative used in the 25URC at Oak Ridge National Laboratory, is to focus the beam at the tube entrance, substantially diluting the effect of the entrance lens. The beam then diverges and so requires an additional lens part way to the terminal. This solution is only partially effective and still necessitates use of shorting rods for low voltage operation. The fact that these elaborate strategies are used is evidence that the alternative of lowering the injection energy as the terminal voltage is lowered imposes enough problems that it is not used in practice. We have modeled a solution that controls the voltage gradient at the tube entrance using an external power supply. This not only maintains the focusing effect of the lens but provides the opportunity to tune the beam by adjusting the entrance lens. A 150 kV power supply outside the pressure vessel feeds a controllable voltage through a high voltage feed-through to the fifth electrode of the accelerator tube. Thus 150 kV on this electrode creates the nominal gradient of 30 kV per

  13. SAFARI 2000 Wetlands Data Set, 1-Deg (Matthews and Fung)

    Data.gov (United States)

    National Aeronautics and Space Administration — This database provides information on the distribution and environmental characteristics of natural wetlands. The database was developed to evaluate the role of...

  14. Development boiling to sprinkled tube bundle

    Science.gov (United States)

    Kracík, Petr; Pospíšil, Jiří

    2016-03-01

    This paper presents results of a studied heat transfer coefficient at the surface of a sprinkled tube bundle where boiling occurs. Research in the area of sprinkled exchangers can be divided into two major parts. The first part is research on heat transfer and determination of the heat transfer coefficient at sprinkled tube bundles for various liquids, whether boiling or not. The second part is testing of sprinkle modes for various tube diameters, tube pitches and tube materials and determination of individual modes' interface. All results published so far for water as the falling film liquid apply to one to three tubes for which the mentioned relations studied are determined in rigid laboratory conditions defined strictly in advance. The sprinkled tubes were not viewed from the operational perspective where there are more tubes and various modes may occur in different parts with various heat transfer values. The article focuses on these processes. The tube is located in a low-pressure chamber where vacuum is generated using an exhauster via ejector. The tube consists of smooth copper tubes of 12 mm diameter placed horizontally one above another.

  15. Development boiling to sprinkled tube bundle

    Directory of Open Access Journals (Sweden)

    Kracík Petr

    2016-01-01

    Full Text Available This paper presents results of a studied heat transfer coefficient at the surface of a sprinkled tube bundle where boiling occurs. Research in the area of sprinkled exchangers can be divided into two major parts. The first part is research on heat transfer and determination of the heat transfer coefficient at sprinkled tube bundles for various liquids, whether boiling or not. The second part is testing of sprinkle modes for various tube diameters, tube pitches and tube materials and determination of individual modes’ interface. All results published so far for water as the falling film liquid apply to one to three tubes for which the mentioned relations studied are determined in rigid laboratory conditions defined strictly in advance. The sprinkled tubes were not viewed from the operational perspective where there are more tubes and various modes may occur in different parts with various heat transfer values. The article focuses on these processes. The tube is located in a low-pressure chamber where vacuum is generated using an exhauster via ejector. The tube consists of smooth copper tubes of 12 mm diameter placed horizontally one above another.

  16. Cases of fallopian tube prolapse

    Directory of Open Access Journals (Sweden)

    Sushil Chawla

    2015-01-01

    Full Text Available Fallopian tube prolapse post hysterectomy is rarely reported complication which can lead to doubts in the mind of young and experienced surgeons alike. This leads to patient morbidity and gets different medical treatments ranging from antibiotics to local applications of copper sulphate, without relief. The use of proper surgical technique, prevention of post operative hematoma and infection go a long way in its prevention.We hereby present two cases, which were manged successfully to relieve the patients of their agony.

  17. Eddy current inspection of tubing

    International Nuclear Information System (INIS)

    Bauza, J. L. R.; Herrero, J.; Diaz, J.

    1966-01-01

    The Experimental research work carried out to develop a Eddy current testing equipment is described. Search coils with ferrite or air cores were used and the obtained results are discussed. Valuable information was gained from a improved channel in which a direct measure of the defect and the reference signal phase difference is obtained. Artificial defect used to evaluate resolution and sensitivity were produced by electro-machining and mechanical means. Finned SAP tubing was tested in a routine basis with the described equipment and the results plotted. Basic and theoretical considerations on the Eddy current testing technique are given in the last section of this report. (Author)

  18. Role of intertube interactions in double- and triple-walled carbon nanotubes.

    Science.gov (United States)

    Hirschmann, Thomas Ch; Araujo, Paulo T; Muramatsu, Hiroyuki; Rodriguez-Nieva, Joaquin F; Seifert, Max; Nielsch, Kornelius; Kim, Yoong Ahm; Dresselhaus, Mildred S

    2014-02-25

    Resonant Raman spectroscopy studies are performed to access information about the intertube interactions and wall-to-wall distances in double- and triple-walled carbon nanotubes. Here, we explain how the surroundings of the nanotubes in a multiwalled system influence their radial breathing modes. Of particular interest, the innermost tubes in double- and triple-walled carbon nanotube systems are shown to be significantly shielded from environmental interactions, except for those coming from the intertube interaction with their own respective host tubes. From a comparison of the Raman results for bundled as well as individual fullerene-peapod-derived double- and triple-walled carbon nanotubes, we observe that metallic innermost tubes, when compared to their semiconducting counterparts, clearly show weaker intertube interactions. Additionally, we discuss a correlation between the wall-to-wall distances and the frequency upshifts of the radial breathing modes observed for the innermost tubes in individual double- and triple-walled carbon nanotubes. All results allow us to contemplate fundamental properties related to DWNTs and TWNTs, as for example diameter- and chirality-dependent intertube interactions. We also discuss differences in fullerene-peapod-derived and chemical vapor deposition grown double- and triple-walled systems with the focus on mechanical coupling and interference effects.

  19. Double shell planar experiments on OMEGA

    Science.gov (United States)

    Dodd, E. S.; Merritt, E. C.; Palaniyappan, S.; Montgomery, D. S.; Daughton, W. S.; Schmidt, D. W.; Cardenas, T.; Wilson, D. C.; Loomis, E. N.; Batha, S. H.; Ping, Y.; Smalyuk, V. A.; Amendt, P. A.

    2017-10-01

    The double shell project is aimed at fielding neutron-producing capsules at the National Ignition Facility (NIF), in which an outer low-Z ablator collides with an inner high-Z shell to compress the fuel. However, understanding these targets experimentally can be challenging when compared with conventional single shell targets. Halfraum-driven planar targets at OMEGA are being used to study physics issues important to double shell implosions outside of a convergent geometry. Both VISAR and radiography through a tube have advantages over imaging through the hohlraum and double-shell capsule at NIF. A number physics issues are being studied with this platform that include 1-d and higher dimensional effects such as defect-driven hydrodynamic instabilities from engineering features. Additionally, the use of novel materials with controlled density gradients require study in easily diagnosed 1-d systems. This work ultimately feeds back into the NIF capsule platform through manufacturing tolerances set using data from OMEGA. Supported under the US DOE by the LANS, LLC under contract DE-AC52-06NA25396. LA-UR-17-25386.

  20. Neutrinoless double beta decay

    Indian Academy of Sciences (India)

    Abstract. The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given.

  1. Reflection Positive Doubles

    OpenAIRE

    Jaffe, Arthur; Janssens, Bas

    2016-01-01

    Here we introduce reflection positive doubles, a general framework for reflection positivity, covering a wide variety of systems in statistical physics and quantum field theory. These systems may be bosonic, fermionic, or parafermionic in nature. Within the framework of reflection positive doubles, we give necessary and sufficient conditions for reflection positivity. We use a reflection-invariant cone to implement our construction. Our characterization allows for a direct interpretation in t...

  2. A double layer review

    International Nuclear Information System (INIS)

    Block, L.P.

    1977-06-01

    A review of the main results on electrostatic double layers (sometimes called space charge layers or sheaths) obtained from theory, and laboratory and space experiments up to the spring of 1977 is given. By means of barium jets and satellite probes, double layers have now been found at the altitudes, earlier predicted theoretically. The general potential distribution above the auroral zone, suggested by inverted V-events and electric field reversals, is corroborated. (author)

  3. Accuracy of Motor Axon Regeneration Across Autograft, Single Lumen, and Multichannel Poly(lactic-co-glycolic Acid) (PLGA) Nerve Tubes

    Science.gov (United States)

    de Ruiter, Godard C.; Spinner, Robert J.; Malessy, Martijn J. A.; Moore, Michael J.; Sorenson, Eric J.; Currier, Bradford L.; Yaszemski, Michael J.; Windebank, Anthony J.

    2012-01-01

    Objective Accuracy of motor axon regeneration becomes an important issue in the development of a nerve tube for motor nerve repair. Dispersion of regeneration across the nerve tube may lead to misdirection and polyinnervation. In this study, we present a series of methods to investigate the accuracy of regeneration, which we used to compare regeneration across autografts and single lumen poly(lactic-co-glycolic acid) (PLGA) nerve tubes. We also present the concept of the multichannel nerve tube that may limit dispersion by separately guiding groups of regenerating axons. Methods Simultaneous tracing of the tibial and peroneal nerves with fast blue (FB) and diamidino yellow (DY), 8 weeks after repair of a 1-cm nerve gap in the rat sciatic nerve, was performed to determine the percentage of double-projecting motoneurons. Sequential tracing of the peroneal nerve with DY 1 week before and FB 8 weeks after repair was performed to determine the percentage of correctly directed peroneal motoneurons. Results In the cases in which there was successful regeneration across single lumen nerve tubes, more motoneurons had double projections to both the tibial and peroneal nerve branches after single lumen nerve tube repair (21.4%) than after autograft repair (5.9%). After multichannel nerve tube repair, this percentage was slightly reduced (16.9%), although not significantly. The direction of regeneration was nonspecific after all types of repair. Conclusion Retrograde tracing techniques provide new insights into the process of regeneration across nerve tubes. The methods and data presented in this study can be used as a basis in the development of a nerve tube for motor nerve repair. PMID:18728579

  4. X-ray tube transformer

    International Nuclear Information System (INIS)

    1980-01-01

    An X-ray generator is described which comprises a transmission line transformer including an electrical conductor with a cavity and a second electrical conductor including helical windings disposed along a longitudinal axis within the cavity of the first conductor. The windings have a pitch which varies per unit length along the axis. There is dielectric material in the cavity for insulation and to couple electromagnetically the two conductors in response to an electric current flowing through the conductors, which have an impedance between them; this varies with distance along the axis of the helix of the second conductor. An X-ray tube is disposed along the longitudinal axis within the cavity, for radiating X-rays. The invention increases the voltage of applied voltage pulses at the remote tube-head with a transformer formed by using a spiral delay line geometry to give a tapered-impedance coaxial high voltage multiplier for pulse voltage operation. This transformer is smaller and lighter than previous designs for the same high peak voltage and power ratings. This is important because the penetration capabilities of Flash X-ray equipment increase with voltage, particularly in heavy materials such as steel. (U.K.)

  5. Narratives From YouTube

    Directory of Open Access Journals (Sweden)

    Mikael Quennerstedt

    2013-10-01

    Full Text Available The aim of this paper is to explore what is performed in students’ and teachers’ actions in physical education practice in terms of “didactic irritations,” through an analysis of YouTube clips from 285 PE lessons from 27 different countries. Didactic irritations are occurrences that Rønholt describes as those demanding “didactic, pedagogical reflections and discussions, which in turn could lead to alternative thinking and understanding about teaching and learning.” Drawing on Barad’s ideas of performativity to challenge our habitual anthropocentric analytical gaze when looking at educational visual data, and using narrative construction, we also aim to give meaning to actions, relations, and experiences of the participants in the YouTube clips. To do this, we present juxtaposing narratives from teachers and students in terms of three “didactic irritations”: (a stories from a track, (b, stories from a game, and (c, stories from a bench. The stories re-present events-of-moving in the data offering insights into embodied experiences in PE practice, making students’ as well as teachers’ actions in PE practice understandable.

  6. Fluoroscopic placement of jejunal feeding tubes

    International Nuclear Information System (INIS)

    Hoffer, F.; Mandell, V.S.; Sandler, R.H.; Leichner, A.; Kaplan, L.C.; Haynie, M.

    1992-01-01

    Over a two-and-one-half year period, 50 children underwent placements of jejunal tubes through a nasal route (NJ, n=47) or through an existing gastrostomy site (GJ, n=119). There were four attempted placements (98% success rate). The NJ tubes remained in place an average of 13 days, and the GJ tubes remained in place an average of 37 days. Fluoroscopic time for placement of an NJ tube an averaged 6 min (29 cases) and for a GJ tube 8 minutes (91 cases). In spite of the limited retention time, fluoroscopic time, and availability of alternative methods, fluoroscopically placed jejunal feedings tubes are still playing an active role in this institution. (orig.)

  7. Tube bundle vibrations in transversal flow

    International Nuclear Information System (INIS)

    Gibert, R.J.; Sagner, M.

    1978-01-01

    This study gives important information concerning characteristic parameters about lock-in and whirling instability phenomena, in the case of tube arrays. The work is mainly an experimental one though models are also developed: 1) an equilateral pitch bundle (p=1,5 D with D=tube diameter) is tested. Tube damping (epsilon) and first eigenfrequency (f), flow velocity are explored in a large domain. Vibratory level of the tubes are measured and critical points are ploted on the fluidelastic parameters diagram. Several bundles with various usual pitches and arrangements (in line or staggered) are tested. Critical velocities are measured and the whirling instability characteristic coefficient is tabulated. A complementary experiment is made on tube rows with various pitches. This gives valuable informations concerning the look-in domain in VR and A'R diagram. Furthermore this puts in evidence the important effect of a frequency difference between two adjacent tubes on the whirling critical velocity

  8. Why do aged fluorescent tubes flicker?

    Science.gov (United States)

    Plihon, Nicolas; Ferrand, Jérémy; Guyomar, Tristan; Museur, Flavien; Taberlet, Nicolas

    2017-11-01

    Our everyday experience of aged and defective fluorescent tubes or bulbs informs us that they may flicker and emit a clicking sound while struggling to light up. In this article, the physical mechanisms controlling the initial illumination of a functioning fluorescent tube are investigated using a simple and affordable experimental setup. Thermionic emission from the electrodes of the tube controls the startup of fluorescent tubes. The origin of the faulty startup of aged fluorescent tubes is discussed and flickering regimes using functional tubes are artificially produced using a dedicated setup that decreases electron emission by the thermionic effect in a controlled manner. The physical parameters controlling the occurrence of flickering light are discussed, and their temporal statistics are reported.

  9. Design of the forward straw tube tracker for the PANDA experiment

    Science.gov (United States)

    Smyrski, J.; Apostolou, A.; Biernat, J.; Czyżycki, W.; Filo, G.; Fioravanti, E.; Fiutowski, T.; Gianotti, P.; Idzik, M.; Korcyl, G.; Korcyl, K.; Lisowski, E.; Lisowski, F.; Płażek, J.; Przyborowski, D.; Przygoda, W.; Ritman, J.; Salabura, P.; Savrie, M.; Strzempek, P.; Swientek, K.; Wintz, P.; Wrońska, A.

    2017-06-01

    The design of the Forward Tracker for the Forward Spectrometer of the PANDA experiment is described. The tracker consists of 6 tracking stations, each comprising 4 planar double layers of straw tube detectors, and has a total material budget of only 2% X0. The straws are made self-supporting by a 1 bar over-pressure of the working gas mixture (Ar/CO2). This allows to use lightweight and compact rectangular support frames for the double layers and to split the frames into pairs of C-shaped half-frames for an easier installation on the beam line.

  10. Numerical investigation of conjugate heat transfer and flow performance of a fin and tube heat exchanger with vortex generators

    DEFF Research Database (Denmark)

    Singh, Shobhana; Sørensen, Kim

    2017-01-01

    Vortex generator is considered as an effective device for augmentation of the thermal-hydraulic performance of a heat exchanger. The aim of present study is to examine the influence of vortex generators on a double fin and tube heat exchanger performance. Vortex generator of rectangular winglet...

  11. Importance of crevices formed between tubes and tube plate for the operational behaviour of heat exchangers

    International Nuclear Information System (INIS)

    Achten, N.; Herbsleb, G.; Wieling, N.

    1986-01-01

    It must be guaranteed by construction and manufacture of heat exchangers that primary and secondary medium are completely separated from each other. When this requirement is fullfilled, the operational use of heat exchangers can be impaired by corrosion reactions within the crevice formed between tube and tube plate which may result in corrosion damage. The various techniques which are in use to connect tubes and tube plate and which are described in the present report, must be valued with respect to the tightness of the connection as well as to the formation of crevices between tubes and tube plate. Corrosion resistant copperbase alloys and stainless steels are the most important materials which are in use for the construction of heat exchangers. The mechanisms of crevice corrosion with unalloyed and low alloy carbon steels, stainless steels, and mixed connections between tube and tube plate with these materials are described in detail. Crevice corrosion may be caused also by the formation of galvanic cells between materials of differing electrochemical response. Furthermore, the concentration of aggressive media in crevices between tubes and tube plate can lead to corrosion damage of heat exchanger tubes. For the service operation of heat exchangers without any hazard of corrosion damage in crevices between tubes and tube plate, such crevices must be avoided by proper construction and manufacture. As a model for suitable measures to avoid crevices, the manufacture of steam generators for PWR's is described. (orig.) [de

  12. A fundamental study on sodium-water reaction in the double-pool-type LMFBR

    International Nuclear Information System (INIS)

    Yoshida, Kazuo; Akimoto, Tokuzo

    1987-01-01

    In order to evaluate the pressure rise by large sodium-water reaction in the Double-Pool LMFBR, basic tests on pressure wave celerity in rectangular tube are carried out. The initial spike pressure in rectangular-shelled steam generator of the Double Pool reactor, strongly depends on pressure wave celerity. In this study, celerity was measured as a function of pressure wave rising time and pulse height, and influence of water around the test section on celerity was investigated. (author)

  13. Preparation of nitrogen-doped carbon tubes

    Science.gov (United States)

    Chung, Hoon Taek; Zelenay, Piotr

    2015-12-22

    A method for synthesizing nitrogen-doped carbon tubes involves preparing a solution of cyanamide and a suitable transition metal-containing salt in a solvent, evaporating the solvent to form a solid, and pyrolyzing the solid under an inert atmosphere under conditions suitable for the production of nitrogen-doped carbon tubes from the solid. Pyrolyzing for a shorter period of time followed by rapid cooling resulted in a tubes with a narrower average diameter.

  14. Vibrations of tube arrays in transversal flow

    International Nuclear Information System (INIS)

    Gibert, R.J.; Doyen, R.

    1981-08-01

    In this study the local forces per unit length acting in a tube in a single row and in bundle have been measured. Their modification by a given harmonic motion of the tube itself or of an adjacent tube has been particularly studied. Some complementary experiments have been performed to extend the whirling coefficient tabulation and also to precise the effect of the upstream velocity profile on the whirling critical velocities [fr

  15. Flow of Jeffrey Fluid through Narrow Tubes

    OpenAIRE

    Nallapu, Santhosh; Radhakrishnamacharya, G.

    2014-01-01

    The present paper deals with a two-fluid model for the flow of Jeffrey fluid in tubes of small diameters. It is assumed that the core region consists of Jeffrey fluid and Newtonian fluid in the peripheral region. Analytical expressions for velocity, effective viscosity, core hematocrit and mean hematocrit have been derived. The effects of various parameters, namely, Jeffrey parameter ({\\lambda}1), tube hematocrit (H0) and tube radius (a) on effective viscosity, core hematocrit and mean hemato...

  16. Performance characteristics of solar blind UV image intensifier tube

    Science.gov (United States)

    Cheng, Hongchang; Shi, Feng; Feng, Liu; Liu, Hui; Ren, Bing; Zhang, Lian-dong

    2009-07-01

    The UV radiation of spectrum range of 200~320nm almost is zero on the earth surface because UV radiation is greatly absorbed by ozone in atmosphere. So this spectrum range is called "Solar Blind Range". Because Solar Blind UV(SBUV) can't be influenced by atmosphere, it is easy to detect them as soon as SBUV radiation objects appear in the earth surface. If UV photoelectric image devices are used to observe them, high contrast picture will be acquired, that bright object's image lie in full black background. It is easy to identify the picture by human eye or other optical sensor (CCD). A solar blind UV(Ultra Violet) image intensifier tube(SBUV-IIT) is a special image intensifier tube, which was developed on double proximity focused Generation low-light-level image intensifier tube. It only responses spectrum range of 200~320 nm., SBUV-IIT can be used to observe UV faint radiation object, because UV sensitivity is high and response time is rapid and radiation gain is high. Low-altitude-flying missile can be observed by detecting its tail fog with SBUV-IIT, because its tail fog emits plenty of SBUV. By this way high contrast UV picture can be acquired to achieve missile warning, and this way has been widely used in foreign ordnance equipment. SBUV-IIT has been described in this paper. It is double proximity focused MCP (Micro-channel plate) image intensifier tube. It is 18mm active diameter of photocathode and phosphor screen. Input and output window is quartz glass and fiber optics faceplate respective. Photocathode material and phosphor screen is tellurium cesium compound and P20. It has been developed with a limiting UV resolution of 39 line pair per millimeter, and spectral response of 200~320 nm, photocathode maximum sensitivity of 29.5 milli-ampere per watt at wavelength 254 nm and a mass of 35g. It can be coupled with CCD easily. It has been well suited for fingerprint identify and camera system, It'll be used for UV hail testing, UV earthquake forecasting and

  17. Acute complications associated with bedside placement of feeding tubes.

    Science.gov (United States)

    Baskin, William N

    2006-02-01

    Several types of feeding tubes can be placed at a patient's bedside; examples include nasogastric, nasointestinal, gastrostomy, and jejunostomy tubes. Nasoenteral tubes can be placed blindly at bedside or with the assistance of placement devices. Nasoenteric tubes can also be placed via fluoroscopy and endoscopy. Gastrostomy and jejunostomy tubes can be placed using endoscopic techniques. This paper will describe the indications and contraindications for different types of tubes that can be placed at the bedside and complications associated with tube placement. Complications associated with nasoenteral tubes include inadvertent malpositioning of the tube, epistaxis, sinusitis, inadvertent tube removal, tube clogging, tube-feeding-associated diarrhea, and aspiration pneumonia. Complications from percutaneous gastrostomy and jejunostomy tube placements include procedure-related mishaps, site infection, leakage, buried bumper syndrome, tube malfunction, and inadvertent removal. These complications will be reviewed, along with a discussion of incidence, cause, treatment, and prevention approaches.

  18. An anti vimentin antibody promotes tube formation

    DEFF Research Database (Denmark)

    Jørgensen, Mathias Lindh; Møller, Carina Kjeldahl; Rasmussen, Lasse

    2017-01-01

    antibody technology, promotes tube formation of endothelial cells in a 2D matrigel assay. By binding vimentin, the antibody increases the tube formation by 21% after 5 hours of incubation. Addition of the antibody directly to cultured endothelial cells does not influence endothelial cell migration...... or proliferation. The enhanced tube formation can be seen for up to 10 hours where after the effect decreases. It is shown that the antibody-binding site is located on the coil 2 domain of vimentin. To our knowledge this is the first study that demonstrates an enhanced tube formation by binding vimentin in a 2D...

  19. Stresses in pin-loaded tubes

    Science.gov (United States)

    Ahmad, Ishtiaq

    This thesis deals with a parametric 3-dimensional photoelastic study of the stresses in pin-loaded tubes, commonly used in securing an aircraft engine into the air frame. Among the geometric variables studied (normalised with reference to the outer tube diameter) are included form values of the ratio of pin-hole diameter to outer tube diameter (0.10, 0.20, 0.40 and 0.60), four different hole-centre positions relative to the tube end and six values of the ratio of tube thickness to outer tube diameter (0.04, 0.08, 0.16, 0.25, 0.32 and 0.50). The other variables investigated are clearance between pin and hole, pin stiffness and lubrication. Some combinations of pairs of pins, either parallel or "crossed" have also been studied, and the effects of different modes of tensile loading, compressive loading, bending loading and torsional loading have been assessed. The results include details of the distribution of normalised changes in tube diameter along the planes of symmetry, the distribution of stress indices around the tube ends, the distribution of stress indices along planes of symmetry and the distribution of stress indices around the pin-loaded holes. The work is discussed in detail. The results provide a valuable reference in the design of pin-loaded tubes.

  20. Failure Analysis of a Service Tube

    Science.gov (United States)

    Xie, Zhongdong; Cai, Weiguo; Li, Zhenxing; Guan, YiMing; Zhang, Baocheng; Yang, XiaoTong

    2017-12-01

    One tube was cracked used in the primary reformer furnace in a fertilizer plant for two and half years. In order to find out the causes of cracking, the methods for chemical composition analysis, macro- and microstructure analysis, penetrant testing, weld analysis, crack and surface damage analysis, mechanics property analysis, high temperature endurance performance analysis, stress and wall thickness calculation were adopted. The integrated assessment results showed that the carbon content of the tube was in the lower limit of the standard range; the tube effective wall thickness was too small; local overheating leads to tube cracking in use process.

  1. Bottom nozzle to guide tube connection

    International Nuclear Information System (INIS)

    Bryan, W.J.

    1991-01-01

    This patent describes a nuclear fuel assembly which includes an upper end fitting and a lower end fitting spaced therefrom and connected thereto by elongated guide tubes of one alloy having an open upper end and a closed lower end with spaced fuel element retaining grids mounted on the guide tubes therebetween, the closed lower ends of the guide tubes including a threaded central passageway and the attachment of the guide tubes to the lower end fitting of another alloy. It comprises: an externally threaded bolt with a first end threadably received in the threaded central passageway of the lower end of the guide tube and a head at the other end of the side of the lower end fitting opposite the guide tube; an interruption in the external threads of the bolt which forms a groove which communicates the interior of the guide tube with the side of the lower end fitting opposite the guide tube and enhances its frictional engagement with the threaded central passageway, thereby to hold and attach the guide tube and lower end fitting firmly together, even through a series of temperature cycles

  2. Numerical study of a VM type multi-bypass pulse tube cryocooler operating at 4K

    Science.gov (United States)

    Pan, Changzhao; Zhang, Tong; Wang, Jue; Chen, Liubiao; Cui, Chen; Wang, Junjie; Zhou, Yuan

    2017-12-01

    VM cryocooler is one kind of Stirling type cryocooler working at low frequency. At present, we have obtained the liquid helium temperature by using a two-stage VM/pulse tube hybrid cryocooler. As a new kind of 4K cryocooler, there are many aspects need to be studied and optimized in detail. In order to reducing the vibration and improving the stability of this cryocooler, a pulse tube cryocooler was designed to get rid of the displacer in the first stage. This paper presents a detail numerical investigation on this pulse tube cryocooler by using the SAGE software. The low temperature phase shifters were adopted in this cryocooler, which were low temperature gas reservoir, low temperature double-inlet and multi-bypass. After optimizing, the structure parameters and the best diameters of orifice, multi-bypass and double-inlet were obtained. With the pressure ratio of about 1.6 and operating frequency 2Hz, this cryocooler could supply above 40mW cooling power at 4.2K, and the total input power needs no more than 60W at 77K. Based on the highest efficiency of 77K high capacity cryocooler, the overall efficiency of this VM type pulse tube cryocooler is above 0.5% relative Carnot efficient.

  3. Digital PIV Measurements of Acoustic Particle Displacements in a Normal Incidence Impedance Tube

    Science.gov (United States)

    Humphreys, William M., Jr.; Bartram, Scott M.; Parrott, Tony L.; Jones, Michael G.

    1998-01-01

    Acoustic particle displacements and velocities inside a normal incidence impedance tube have been successfully measured for a variety of pure tone sound fields using Digital Particle Image Velocimetry (DPIV). The DPIV system utilized two 600-mj Nd:YAG lasers to generate a double-pulsed light sheet synchronized with the sound field and used to illuminate a portion of the oscillatory flow inside the tube. A high resolution (1320 x 1035 pixel), 8-bit camera was used to capture double-exposed images of 2.7-micron hollow silicon dioxide tracer particles inside the tube. Classical spatial autocorrelation analysis techniques were used to ascertain the acoustic particle displacements and associated velocities for various sound field intensities and frequencies. The results show that particle displacements spanning a range of 1-60 microns can be measured for incident sound pressure levels of 100-130 dB and for frequencies spanning 500-1000 Hz. The ability to resolve 1 micron particle displacements at sound pressure levels in the 100 dB range allows the use of DPIV systems for measurement of sound fields at much lower sound pressure levels than had been previously possible. Representative impedance tube data as well as an uncertainty analysis for the measurements are presented.

  4. Working session 2: Tubing inspection

    International Nuclear Information System (INIS)

    Guerra, J.; Tapping, R.L.

    1997-01-01

    This session was attended by delegates from 10 countries, and four papers were presented. A wide range of issues was tabled for discussion. Realizing that there was limited time available for more detailed discussion, three topics were chosen for the more detailed discussion: circumferential cracking, performance demonstration (to focus on POD and sizing), and limits of methods. Two other subsessions were organized: one dealt with some challenges related to the robustness of current inspection methods, especially with respect to leaving cracked tubes in service, and the other with developing a chart of current NDE technology with recommendations for future development. These three areas are summarized in turn, along with conclusions and/or recommendations. During the discussions there were four presentations. There were two (Canada, Japan) on eddy current probe developments, both of which addressed multiarray probes that would detect a range of flaws, one (Spain) on circumferential crack detection, and one (JRC, Petten) on the recent PISC III results

  5. Paramecium swimming in capillary tube

    Science.gov (United States)

    Jana, Saikat; Um, Soong Ho; Jung, Sunghwan

    2012-04-01

    Swimming organisms in their natural habitat need to navigate through a wide range of geometries and chemical environments. Interaction with boundaries in such situations is ubiquitous and can significantly modify the swimming characteristics of the organism when compared to ideal laboratory conditions. We study the different patterns of ciliary locomotion in glass capillaries of varying diameter and characterize the effect of the solid boundaries on the velocities of the organism. Experimental observations show that Paramecium executes helical trajectories that slowly transition to straight lines as the diameter of the capillary tubes decreases. We predict the swimming velocity in capillaries by modeling the system as a confined cylinder propagating longitudinal metachronal waves that create a finite pressure gradient. Comparing with experiments, we find that such pressure gradient considerations are necessary for modeling finite sized ciliary organisms in restrictive geometries.

  6. Atmospheres in a Test Tube

    Science.gov (United States)

    Claudi, R.; Erculiani, M. S.; Giro, E.; D'Alessandro, M.; Galletta, G.

    2013-09-01

    The "Atmosphere in a Test Tube" project is a laboratory experiment that will be able to reproduce condition of extreme environments by means of a simulator. These conditions span from those existing inside some parts of the human body to combinations of temperatures, pressures, irradiation and atmospheric gases present on other planets. In this latter case the experiments to be performed will be useful as preliminary tests for both simulation of atmosphere of exoplanets and Solar System planets and Astrobiology experiments that should be performed by planetary landers or by instruments to be launched in the next years. In particular at INAF Astronomical Observatory of Padova Laboratory we are approaching the characterization of extrasolar planet atmospheres taking advantage by innovative laboratory experiments with a particular focus on low mass Neptunes and Super earths and low mass M dwarfs primaries.

  7. Failure analysis of retired steam generator tubings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hong Pyo; Kim, J. S.; Hwang, S. S. and others

    2005-04-15

    Degradation of steam generator leads to forced outage and extension of outage, which causes increase in repair cost, cost of purchasing replacement power and radiation exposure of workers. Steam generator tube rupture incident occurred in Uljin 4 in 2002, which made public sensitive to nuclear power plant. To keep nuclear energy as a main energy source, integrity of steam generator should be demonstrated. Quantitative relationship between ECT(eddy current test) signal and crack size is needed in assesment of integrity of steam generator in pressurized water reactor. However, it is not fully established for application in industry. Retired steam generator of Kori 1 has many kinds of crack such as circumferential and axial primary water stress corrosion crack and outer diameter stress corrosion crack(ODSCC). So, it can be used in qualifying and improving ECT technology and in condition monitoring assesment for crack detected in ISI(in service inspection). In addition, examination of pulled tube of Kori 1 retired steam generator will give information about effectiveness of non welded sleeving technology which was employed to repair defect tubes and remedial action which was applied to mitigate ODSCC. In this project, hardware such as semi hot lab. for pulled tube examination and modification transportation cask for pulled tube and software such as procedure of transportation of radioactive steam generator tube and non-destructive and destructive examination of pulled tube were established. Non-destructive and destructive examination of pulled tubes from Kori 1 retired steam generator were performed in semi hot lab. Remedial actions applied to Kori 1 retired steam generator, PWSCC trend and bulk water chemistry and crevice chemistry in Kori 1 were evaluated. Electrochemical decontamination technology for pulled tube was developed to reduce radiation exposure and enhance effectiveness of pulled tube examination. Multiparameter algorithm developed at ANL, USA was

  8. Observation of "YouTube" Language Learning Videos ("YouTube" LLVS)

    Science.gov (United States)

    Alhamami, Munassir

    2013-01-01

    This paper navigates into the "YouTube" website as one of the most usable online tools to learn languages these days. The paper focuses on two issues in creating "YouTube" language learning videos: pedagogy and technology. After observing the existing "YouTube" LLVs, the study presents a novel rubric that is directed…

  9. Effect of Tube Pitch on Pool Boiling Heat Transfer of Vertical Tube Bundle

    International Nuclear Information System (INIS)

    Kang, Myeong Gie

    2016-01-01

    Summarizing the previous results it can be stated that heat transfer coefficients are highly dependent on the tube pitch and the heat flux of the relevant tube. The published results are mostly about the horizontal tubes. However, there are many heat exchangers consisting of vertical tubes like AP600. Therefore, the focus of the present study is an identification of the effects of a tube pitch as well as the heat flux of a relevant tube on the heat transfer of a tube bundle installed vertically. When the heat flux is increased many bubbles are generating due to the increase of the nucleation sites. The bubbles become coalescing with the nearby bubbles and generates big bunches of bubbles on the tube surface. This prevents the access of the liquid to the surface and deteriorates heat transfer. The bubble coalescence is competing with the mechanisms enhancing heat transfer. The pitch was varied from 28.5 mm to 95 mm and the heat flux of the nearby tube was changed from 0 to 90kW/m 2 . The enhancement of the heat transfer is clearly observed when the heat flux of the nearby tube becomes larger and the heat flux of the upper tube is less than 40kW/m 2 . The effect of the tube pitch on heat transfer is negligible as the value of DP/ is increased more than 4.

  10. Study of a double bubbler for material balance in liquids

    Energy Technology Data Exchange (ETDEWEB)

    Hugues Lambert

    2013-09-01

    The objective of this project was to determine the potential of a double bubbler to measure density and fluid level of the molten salt contained in an electrorefiner. Such in-situ real-time measurements can provide key information for material balances in the pyroprocessing of the nuclear spent fuel. This theoretical study showed this technique has a lot of promise. Four different experiments were designed and performed. The first three experiments studied the influence of a variety of factors such as depth difference between the two tubes, gas flow rate, the radius of the tubes and determining the best operating conditions. The last experiment purpose was to determine the precision and accuracy of the apparatus during specific conditions. The elected operating conditions for the characterization of the system were a difference of depth of 25 cm and a flow rate of 55 ml/min in each tube. The measured densities were between 1,000 g/l and 1,400g/l and the level between 34cm and 40 cm. The depth difference between the tubes is critical, the larger, the better. The experiments showed that the flow rate should be the same in each tube. The concordances with theoretical predictions were very good. The density precision was very satisfying (spread<0.1%) and the accuracy was about 1%. For the level determination, the precision was also very satisfying (spread<0.1%), but the accuracy was about 3%. However, those two biases could be corrected with calibration curves. In addition to the aqueous systems studied in the present work, future work will focus on examining the behavior of the double bubbler instrumentation in molten salt systems. The two main challenges which were identified in this work are the effect of the temperature and the variation of the superficial tension.

  11. Double containment shell for nuclear power plants

    International Nuclear Information System (INIS)

    Sykora, D.

    1977-01-01

    A double containment shell is proposed for nuclear power plants, especially those equipped with pressurized water reactors. The shell offers increased environmental protection from primary circuit accidents. The inner shell is built of steel or concrete while the outer shell is always built of concrete. The space between the two shells is filled with water and is provided with several manholes and with stiffeners designed for compensation for load due to the water hydrostatic pressure. Water serves the airtight separation of the containment shell inside from the environment and the absorption of heat released in a primary circuit accident. In case the inner shell is made of concrete, it is provided with heat-removal tubes in-built in its walls ensuring rapid heat transfer from the inside of the containment to the water in the interwall space. (Z.M.)

  12. Tuning of sorted double-walled carbon nanotubes by electrochemical charging.

    Science.gov (United States)

    Kalbac, Martin; Green, Alexander A; Hersam, Mark C; Kavan, Ladislav

    2010-01-26

    Double-walled carbon nanotubes sorted by density gradient ultracentrifugation were examined by Raman spectroscopy and by in situ Raman spectroelectrochemistry. The sorted samples had a narrow distribution of diameters of both inner and outer tubes, which enabled a comparison of the behavior of inner metallic tubes and inner semiconducting nanotubes as a function of the applied electrochemical potential. The metallic inner tubes were efficiently doped even though they were protected from electrolyte ions by the outer wall, whereas the doping of semiconducting inner tubes was observed only at high magnitudes of the electrode potential. These results indicate that the doping response of inner tubes is predominantly controlled by inner tube electronic properties. On the other hand, the effect of electronic structure of the outer tube on the behavior of inner tube is weak. Furthermore, the efficiency of the charge transfer from outer to inner wall depends on the doping level. A low doping level corresponds to a high efficiency of the charge-transfer, while a high doping level shows low charge-transfer efficiency.

  13. Project Half Double

    DEFF Research Database (Denmark)

    Svejvig, Per; Ehlers, Michael; Adland, Karoline Thorp

    and as an opportunity rather than a threat and a risk. We are convinced that by doing so, we can strengthen Denmark’s competitiveness and play an important role in the battle for jobs and future welfare. The overall goal is to deliver “projects in half the time with double the impact”, where projects in half the time...... many of the key performance indicators associated with them can be evaluated (Grundfos and Siemens Wind Power). In addition to the current status of delivering impact faster for the seven pilot projects, it is important to highlight that Project Half Double phase 1 has planted many seeds in the pilot......Project Half Double has a clear mission to succeed in finding a project methodology that can increase the success rate of our projects while increasing the speed at which we generate new ideas and develop new products and services. Chaos and complexity should be seen as a basic condition...

  14. Dynamics and control of trajectory tubes theory and computation

    CERN Document Server

    Kurzhanski, Alexander B

    2014-01-01

    This monograph presents theoretical methods involving the Hamilton–Jacobi–Bellman formalism in conjunction with set-valued techniques of nonlinear analysis to solve significant problems in dynamics and control. The emphasis is on issues of reachability, feedback control  synthesis under complex state constraints, hard or double bounds on controls, and performance in finite time. Guaranteed state estimation, output feedback control, and hybrid dynamics are also discussed. Although the focus is on systems with linear structure, the authors indicate how to apply each approach to nonlinear and nonconvex systems. The main theoretical results lead to computational schemes based on extensions of ellipsoidal calculus that provide complete solutions to the problems. These computational schemes in turn yield software tools that can be applied effectively to high-dimensional systems. Dynamics and Control of Trajectory Tubes: Theory and Computation will interest graduate and senior undergraduate students, as well as...

  15. How to pass a nasogastric tube.

    Science.gov (United States)

    Dyer, I; Ashton, W B

    1991-01-01

    The passage of a nasogastric tube may be met with some difficulty. The indications and contraindications for, and the method of insertion of, the tube are described, as are the difficulties that may be encountered, their solutions, and the complications that may result from the procedure.

  16. Teaching Shakespeare with YouTube

    Science.gov (United States)

    Desmet, Christy

    2009-01-01

    YouTube, the video sharing website that allows viewers to upload video content ranging from cute dog tricks to rare rock videos, also supports a lively community devoted to the performance of Shakespeare and Shakespearean adaptations. YouTube is also a popular site for student producers of Shakespeare performances, parodies, and other artistic…

  17. Arrested segregative phase separation in capillary tubes

    NARCIS (Netherlands)

    Tromp, R. Hans; Lindhoud, Saskia

    2006-01-01

    Phase separation in a capillary tube with one of the phases fully wetting the capillary wall is arrested when the typical size of the phase domains reaches the value of the diameter of the tube. The arrested state consists of an alternating sequence of concave-capped and convex-capped cylindrical

  18. X-ray tubes for computed tomography

    International Nuclear Information System (INIS)

    Kotabe, Munenori; Sado, Noriyuki; Tachiki, Shigeru; Kitsuya, Minoru

    1979-01-01

    The X-ray tomography by computer processing (CT) is rapidly spreading because of the capabilities to obtain useful diagnostic information quantitatively, which was not able to be obtained by conventional X-ray photography, and to perform no-intrusion inspection, because it can picture the difference of X-ray absorption coefficient of several per cent in the soft tissues inside craniums. As the X-ray tubes to meet these requirements, the fixed anode X-ray tubes having high continuous rating are required for head CT, while the rotary anode X-ray tubes having the large cumulative heat capacity of anodes for whole body CT. Hitachi Ltd. has developed the X-ray tubes of type H 7129 of 4 kW rating for head CT and of type UJ-6FC-05V of 300 kHU (heat unit) for whole body CT. The specifications required for respective X-ray tubes include several items, and the maximum working tube voltage, focusing dimensions, long or short term maximum input and others are reported for the above described tubes. The performance centering around the loading life-time is described. In the tubes for whole body CT, repeated loading is also investigated. For the assumed input of 70,000 HU/slice, repeated loading of 10 times or more is possible in both cases when the input is repeatedly applied at loading intervals of 90 and 120 sec. (Wakatsuki, Y.)

  19. Sampling Artifacts from Conductive Silicone Tubing

    Energy Technology Data Exchange (ETDEWEB)

    Timko, Michael T.; Yu, Zhenhong; Kroll, Jesse; Jayne, John T.; Worsnop, Douglas R.; Miake-Lye, Richard C.; Onasch, Timothy B.; Liscinsky, David; Kirchstetter, Thomas W.; Destaillats, Hugo; Holder, Amara L.; Smith, Jared D.; Wilson, Kevin R.

    2009-05-15

    We report evidence that carbon impregnated conductive silicone tubing used in aerosol sampling systems can introduce two types of experimental artifacts: 1) silicon tubing dynamically absorbs carbon dioxide gas, requiring greater than 5 minutes to reach equilibrium and 2) silicone tubing emits organic contaminants containing siloxane that adsorb onto particles traveling through it and onto downstream quartz fiber filters. The consequence can be substantial for engine exhaust measurements as both artifacts directly impact calculations of particulate mass-based emission indices. The emission of contaminants from the silicone tubing can result in overestimation of organic particle mass concentrations based on real-time aerosol mass spectrometry and the off-line thermal analysis of quartz filters. The adsorption of siloxane contaminants can affect the surface properties of aerosol particles; we observed a marked reduction in the water-affinity of soot particles passed through conductive silicone tubing. These combined observations suggest that the silicone tubing artifacts may have wide consequence for the aerosol community and should, therefore, be used with caution. Gentle heating, physical and chemical properties of the particle carriers, exposure to solvents, and tubing age may influence siloxane uptake. The amount of contamination is expected to increase as the tubing surface area increases and as the particle surface area increases. The effect is observed at ambient temperature and enhanced by mild heating (<100 oC). Further evaluation is warranted.

  20. Fibreoptic Bronchoscope for Nasogastric Tube Placement

    Directory of Open Access Journals (Sweden)

    Bhandari Dhiraj

    2015-09-01

    Full Text Available A patient of stage III squamous cell carcinoma of mandible with hemi-mandibulectomy, modified radical neck dissection and radiotherapy required Ryle’s Tube (RT insertion for feeding. This case report describes use of fibreoptic bronchoscope to place an endotracheal tube in oesophagus through nasal route which was then used as a conduit to pass a RT into stomach.

  1. Models of Flux Tubes from Constrained Relaxation

    Indian Academy of Sciences (India)

    tribpo

    Equilibria corresponding to the energy extrema while conserving these invariants for parallel flows yield three classes of ... parallel heat flux, due to the boundary condition Β · n = 0, that the total energy, is conserved. In all HR, K, S, and the total mass, ... Zero net current flux tubes are qualitatively similar to the flux tube with ...

  2. Sound absorption and reflection with coupled tubes

    NARCIS (Netherlands)

    van der Eerden, F.J.M.

    2000-01-01

    This paper describes a special sound absorbing technique with an accompanying efficient numerical design tool. As a basis pressure waves in a single narrow tube or pore are considered. In such a tube the viscosity and the thermal conductivity of the air, or any other fluid, can have a significant

  3. Development of Zirconium alloys (for pressure tubes)

    International Nuclear Information System (INIS)

    Kim, Young Suk; Kwon, Sang Chul; Choo, Ki Nam; Jung, Chung Hwan; Yim, Kyong Soo; Kim, Sung Soo; Baek, Jong Hyuk; Jeong, Yong Hwan; Kim, Kyong Ho; Cho, Hae Dong; Hwang, S. K.; Kim, M. H.; Kwon, S. I; Kim, I. S.

    1997-09-01

    The objective of this research is to set up the basic technologies for the evaluation of pressure tube integrity and to develop improved zirconium alloys to prevent pressure tube failures due to DHC and hydride blister caused by excessive creep-down of pressure tubes. The experimental procedure and facilities for characterization of pressure tubes were developed. The basic research related to a better understanding of the in-reactor performances of pressure tubes leads to noticeable findings for the first time : the microstructural effect on corrosion and hydrogen pick-up behavior of Zr-2.5Nb pressure tubes, texture effect on strength and DHC resistance and enhanced recrystallization by Fe in zirconium alloys and etc. Analytical methodology for the assessment of pressure tubes with surface flaws was set up. A joint research is being under way with AECL to determine the fracture toughness of O-8 at the EOL (End of Life) that had been quadruple melted and was taken out of the Wolsung Unit-1 after 10 year operation. In addition, pressure tube with texture controlled is being made along with VNINM in Russia as a joint project between KAERI and Russia. Finally, we succeeded in developing 4 different kinds of zirconium alloys with better corrosion resistance, low hydrogen pickup fraction and higher creep strength. (author). 121 refs., 65 tabs., 260 figs

  4. The pulse tube and the pendulum.

    Science.gov (United States)

    Swift, G W; Backhaus, S

    2009-11-01

    An inverted pulse tube in which gravity-driven convection is suppressed by acoustic oscillations is analogous to an inverted pendulum that is stabilized by high-frequency vibration of its pivot point. Gravity acts on the gas density gradient arising from the end-to-end temperature gradient in the pulse tube, exerting a force proportional to that density gradient, tending to cause convection when the pulse tube is inverted. Meanwhile, a nonlinear effect exerts an opposing force proportional to the square of any part of the density gradient that is not parallel to the oscillation direction. Experiments show that convection is suppressed when the pulse-tube convection number N(ptc)=omega(2)a(2)DeltaT/T(avg)/[g(alphaD sin theta-L cos theta)] is greater than 1 in slender tubes, where omega is the radian frequency of the oscillations, a is their amplitude, DeltaT is the end-to-end temperature difference, T(avg) is the average absolute temperature, g is the acceleration of gravity, L is the length of the pulse tube and D is its diameter, alpha is about 1.5, and the tip angle theta ranges from 90 degrees for a horizontal tube to 180 degrees for an inverted tube. Theory suggests that the temperature dependence should be DeltaT/T(avg) instead of DeltaT/T(avg).

  5. Thermodynamic analysis of a pulse tube engine

    International Nuclear Information System (INIS)

    Moldenhauer, Stefan; Thess, André; Holtmann, Christoph; Fernández-Aballí, Carlos

    2013-01-01

    Highlights: ► Numerical model of the pulse tube engine process. ► Proof that the heat transfer in the pulse tube is out of phase with the gas velocity. ► Proof that a free piston operation is possible. ► Clarifying the thermodynamic working principle of the pulse tube engine. ► Studying the influence of design parameters on the engine performance. - Abstract: The pulse tube engine is an innovative simple heat engine based on the pulse tube process used in cryogenic cooling applications. The working principle involves the conversion of applied heat energy into mechanical power, thereby enabling it to be used for electrical power generation. Furthermore, this device offers an opportunity for its wide use in energy harvesting and waste heat recovery. A numerical model has been developed to study the thermodynamic cycle and thereby help to design an experimental engine. Using the object-oriented modeling language Modelica, the engine was divided into components on which the conservation equations for mass, momentum and energy were applied. These components were linked via exchanged mass and enthalpy. The resulting differential equations for the thermodynamic properties were integrated numerically. The model was validated using the measured performance of a pulse tube engine. The transient behavior of the pulse tube engine’s underlying thermodynamic properties could be evaluated and studied under different operating conditions. The model was used to explore the pulse tube engine process and investigate the influence of design parameters.

  6. Non-uniform tube representation of proteins

    DEFF Research Database (Denmark)

    Hansen, Mikael Sonne

    might not correctly capture volume exclusion - of crucial importance when trying to understand a proteins $3$d-structure. We propose a new reduced model treating the protein as a non-uniform tube with a radius reflecting the positions of atoms. The tube representation is well suited considering X...

  7. Places to Go: YouTube

    Science.gov (United States)

    Downes, Stephen

    2008-01-01

    Founded in 2005 by three former PayPal employees, YouTube has revolutionized the Internet, marking a change from the static Internet to the dynamic Internet. In this edition of Places to Go, Stephen Downes discusses how the rise of a ubiquitous media format--Flash video--has made YouTube's success possible and argues that Flash video has important…

  8. Confined Tube Crimp Using Portable Hand Tools

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, Joseph James [Los Alamos National Laboratory; Pereyra, R. A. [LANL Retired; Archuleta, Jeffrey Christopher [Los Alamos National Laboratory; Martinez, Isaac P. [Los Alamos National Laboratory; Nelson, A. M. [MST-16 Summer Student (2007); Allen, Ronald Scott [Los Alamos National Laboratory; Page, R. L. [LANL Retired; Freer, Jerry Eugene [Los Alamos National Laboratory; Dozhier, Nathan Gus [Los Alamos National Laboratory

    2016-04-04

    The Lawrence Radiation Laboratory developed handheld tools that crimp a 1/16 inch OD tube, forming a leak tight seal1 (see Figure 1). The leak tight seal forms by confining the 1/16 inch OD tubing inside a die while applying crimp pressure. Under confined pressure, the tube walls weld at the crimp. The purpose of this study was to determine conditions for fabricating a leak tight tube weld. The equipment was used on a trial-and-error basis, changing the conditions after each attempt until successful welds were fabricated. To better confine the tube, the die faces were polished. Polishing removed a few thousandths of an inch from the die face, resulting in a tighter grip on the tubing wall. Using detergent in an ultrasonic bath, the tubing was cleaned. Also, the time under crimp pressure was increased to 30 seconds. With these modifications, acceptable cold welds were fabricated. After setting the conditions for an acceptable cold weld, the tube was TIG welded across the crimped face.

  9. Broadcast yourself on YouTube - really?

    NARCIS (Netherlands)

    Kruitbosch, G.; Nack, F.

    2008-01-01

    One essential reason for people to publish on the web is to express themselves freely. YouTube facilitates this self-expression by allowing users to upload video content they generated. This paper investigates to what extent the videos on YouTube are self-generated content, instead of amalgamated

  10. Fluid dynamics and vibration of tube banks in fluid flow

    International Nuclear Information System (INIS)

    Zukauskas, A.; Ulinskas, R.; Katinas, V.

    1988-01-01

    This work presents results derived in fluid dynamics, hydraulic drag and flow-induced vibrations within transverse and yawed tube banks. The studies encompass banks of smooth, rough and finned tubes at Reynolds numbers from 1 to 2x10/sup 6/. Highlighted in the text are fluid dynamic parameters of tube banks measured at inter-tube spaces and tube surfaces

  11. Square tubing reduces cost of telescoping bridge crane hoist

    Science.gov (United States)

    Bernstein, G.; Graae, J.; Schraidt, J.

    1967-01-01

    Using standard square tubing in a telescoping arrangement reduces the cost of a bridge crane hoist. Because surface tolerances of square tubing need not be as accurate as the tubing used previously and because no spline is necessary, the square tubing is significantly less expensive than splined telescoping tubes.

  12. Double Chooz experiment

    International Nuclear Information System (INIS)

    Palomares, C.

    2009-01-01

    Double Chooz will use two identical detectors at different distances from the Chooz nuclear power station to search for a non-vanishing value of θ 13 , and, hopefully, to open the way to experiments aspiring to discover CP violation in the leptonic sector. The far detector is expected to be operative by the end of 2009. Installation of the near detector will occur in 2010. Double Chooz has the capacity to exclude sin 2 (2θ 13 ) 31 2 = 2.5 x 10 -3 eV 2 with three years of data running both near and far detectors. (author)

  13. John Deakin: Double Exposures

    Directory of Open Access Journals (Sweden)

    Paul Rousseau

    2015-11-01

    Full Text Available In this series of short films made by Jonathan Law, the art historian James Boaden, and the curator of The John Deakin Archive, Paul Rousseau, discuss the double-exposure images made by the photographer John Deakin (1912-1972 in the 1950s and 1960s. The films ask you, firstly, to look closely at the images being discussed. Each one begins with a sustained and intense shot of a single image before opening up to a wide-ranging discussion about Deakin, double exposures, and photography.

  14. Pneumothorax occurring after nasogastric tube removal

    Science.gov (United States)

    Paul, Vishesh; Shenoy, Amith; Kupfer, Yizhak; Tessler, Sidney

    2013-01-01

    An 85-year-old woman with failure to thrive due to poor oral intake was admitted owing to dehydration. A nasogastric (NG) tube was inserted for the initiation of enteral feedings. The tube position was confirmed by gastric auscultation after insufflating air through the tube. A chest X-ray revealed that the NG tube traversed the right main stem bronchus with its tip ending in the right costophrenic angle adjacent to the pleura. No pneumothorax was identified. The tube was removed and a short while later the patient developed mild chest discomfort. A repeat chest X-ray revealed significant pneumothorax on the right side. She was treated conservatively with 100% oxygen with successful resolution of the pneumothorax. PMID:24296770

  15. Coke from small-diameter tubes analyzed

    International Nuclear Information System (INIS)

    Albright, L.F.

    1988-01-01

    The mechanism for coke deposit formation and the nature of the coke itself can vary with the design of the ethylene furnace tube bank. In this article, coke deposits from furnaces with small-diameter pyrolysis tubes are examined. The samples were taken from four furnaces of identical design (Plant B). As in both the first and second installments of the series, the coke deposits were examined using a scanning electron microscope (SEM) and an energy dispersive X-ray analyzer (EDAX). The deposits from the small-diameter tubes are compared with the coke deposits from the furnace discussed in earlier articles. Analysis of the coke in both sets of samples are then used to offer recommendations for improved decoking procedures, operating procedures, better feed selection, and better selection of the metallurgy used in furnace tubes, to extend the operating time of the furnace tubes by reducing the amount and type of coke build up

  16. Pressure tube rupture in a closed tank

    International Nuclear Information System (INIS)

    Khater, H.A.; Hadaller, G.I.; Stern, F.

    1985-06-01

    A study has been prepared on the feasibility of conducting pressure tube/calandria tube rupture tests in a closed tank, simulating a scaled-down calandria vessel. The study includes: i) a review of previous work, ii) an analytical investigation of the scaling problem of the calandria vessel and relevant in-core structures, iii) selection of a method for initiating pressure tube/calandria tube rupture, iv) a set of specifications for the test assembly, v) general arrangement drawings, vi) a proposal for a test matrix, vii) a survey and evaluation of existing facilities which could provide the required high pressure, temperature and fluid inventory, and viii) a cost estimate for the detailed design and construction, instrumentation, data acquisition and reduction, testing and reporting. The study concludes that it is both technically and practically feasible to conduct pressure tube rupture tests in a closed tank

  17. Experimental study of tube/support impact forces in multi-span PWR steam generator tubes

    International Nuclear Information System (INIS)

    Axisa, F.; Desseaux, A.; Gibert, R.J.

    1984-12-01

    The vibro-impact response of a straight part of a steam generator tube is investigated experimentally and using numerical simulation with the aim to relate tube overall dynamics with excitation and tube-support clearance. Configuration studied here corresponds to the tube being excited in only one direction at its first resonance presenting an antinode of vibration at the impacted support. Tests show namely that midspan displacement of tube is almost proportional to excitation level and clearance. Impact forces averaged over a cycle of vibration are almost proportional to excitation and poorly dependent on clearance. Results of numerical simulation are in fairly good agreement with test results

  18. Design and Realization Aspects of 1-THz Cascade Backward Wave Amplifier Based on Double Corrugated Waveguide

    DEFF Research Database (Denmark)

    Paoloni, Claudio; Di Carlo, Aldo; Bouamrane, Fayçal

    2013-01-01

    The design and fabrication challenges in the first ever attempt to realize a 1-THz vacuum tube amplifier are described. Implementation of innovative solutions including a slow-wave structure in the form of a double corrugated waveguide, lateral tapered input and output couplers, deep X-ray LIGA...

  19. 0011-0030.IEEE 754: 64 Bit Double Precision FloatsThis.pdf | 01 ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.IEEE 754: 64 Bit Double Precision FloatsThis.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. 29th Mid-year meeting. Posted on 19 ...

  20. Revisiting the Fully Automated Double-Ring Infiltrometer Using Open-Source Electronics

    Science.gov (United States)

    The double-ring infiltrometer (DRI) is commonly used for measuring soil hydraulic conductivity. However, constant-head DRI tests typically involve the use of Mariotte tubes, which can be problematic to set-up, and time-consuming to maintain and monitor during infiltration tests....

  1. Observation of X-ray intensity distribution from the anode of a fine-focus tube using Δω - Δ2θ scans

    International Nuclear Information System (INIS)

    Grigg, M.W.; Barnea, Z.; Maslen, V.W.

    1995-01-01

    A split intensity distribution from the anode of fine focus x-ray tubes probably due to tungsten deposited on the target is reported. Such a doubling of the target complicates the interpretation of Δ ω -Δ2θ intensity distributions and introduces systematic errors in the determination of lattice parameters. It is estimated that the increasing tungsten deposit affects, in time, the intensity of x-ray tubes. 4 refs., 4 figs

  2. Nasogastric tube as protection for recurrent oesophageal stricture: a case report.

    Science.gov (United States)

    Woynarowski, Marek; Dądalski, Maciej; Wojno, Violetta; Teisseyre, Mikołaj; Szymczak, Marek; Chyżyńska, Anna; Hurkała, Leszek; Płowiecki, Emil; Kmiotek, Jakub

    2014-04-28

    This report presents the case of an 8.5-year-old boy with Down syndrome after experiencing extensive caustic injury to the oesophagus and stomach resulting from the accidental ingestion of concentrated sulphuric acid. The patient had undergone 32 unsuccessful endoscopic oesophageal stricture dilatations and stenting procedures performed over a period of 15 mo following the accident. Surgical reconstruction of the oesophagus was not possible due to previous gastric and cardiac surgeries for congenital conditions. Before referring the patient for salivary fistula surgery, the patient received a nasogastric tube with perforations located above the upper margin of the oesophageal stenosis for the passage of saliva and fluid. The tube was well tolerated and improved swallowing; however the backflow of gastric contents caused recurrent infections of the respiratory tract. To overcome these problems, we developed a double lumen, varying diameter, perforated tube for protection of the oesophageal closure. This nasogastric tube was found to be safe and decreased the need for hospitalization and further endoscopic procedures. This newly developed tube can thus be considered as a treatment option for patients with recurrent oesophageal stenosis and contraindications for surgical oesophageal reconstruction.

  3. Effect of the inertance tube on the performance of the Stirling type pulse tube refrigerator

    International Nuclear Information System (INIS)

    Hong, Yong Ju; Park, Seong Je; Kim, Hyo Bong; Kim, Yang Hoon; Choi, Young Don

    2002-01-01

    The Pulse Tube Refrigerator(PTR), which has no moving parts at its cold section, is attractive for obtaining higher reliability, simpler construction and lower vibration than in any other small cryocoolers. Commonly used mean to achieve optimum performance of the PTR are orifice or inertance tube. The Stirling type Pulse Tube Refrigerator in the experiments consists of a compressor driven by linear motors, which make pressure waves, a regenerator, a pulse tube with inertance tube, and a buffer. The pressures and temperature are measured to explore the dependency of inertance tube on the performance of the PTR. The results show the dependency of cool-down characteristics, no-load temperature on frequency of operation and inertance tube

  4. On the distribution of temperatures in steam generator tubes at tube support plate Intersections

    International Nuclear Information System (INIS)

    Cizelj, L.; Dvorsek, T.; Petelin, S.

    1995-01-01

    This analysis was initiated to examine the temperature fields in the steam generator tube in the vicinity of the tube support plates. It is assumed that the flow of the secondary coolant is severely disturbed there, which causes local heating of the tube surface. Different designs of tube support plates (a drilled hole - NE Krsko, broached trefoil and broached quatrefoil designs) were assessed and compared. Inside the drilled hole tube support plate, the temperature of the reactor coolant. Inside broached trefoil and quatrefoil support plates, the tube surface temperature reaches about 10K less than reactor coolant temperature. The most important result concerning the Krsko specific conditions is that the frequency of the detected defects can be correlated with the temperature of the tube outer surface and void fraction of the secondary coolant. (author)

  5. Layered double hydroxides

    DEFF Research Database (Denmark)

    López Rayo, Sandra; Imran, Ahmad; Hansen, Hans Chr. Bruun

    2017-01-01

    A novel zinc (Zn) fertilizer concept based on Zn doped layered double hydroxides (Zn-doped Mg-Fe-LDHs) has been investigated. Zn-doped Mg-Fe-LDHs were synthetized, their chemical composition was analyzed and their nutrient release was studied in buffered solutions with different pH values. Uptake...

  6. Beyond the double banana

    DEFF Research Database (Denmark)

    Rosenzweig, Ivana; Fogarasi, András; Johnsen, Birger

    2014-01-01

    performance was compared with the double banana (longitudinal bipolar montage, 10-20 array). RESULTS: Adding the inferior temporal electrode chain, computed montages (reference free, common average, and source derivation), and voltage maps significantly increased the sensitivity. Phase maps had the highest...

  7. Double aortic arch

    Science.gov (United States)

    Surgery can be done to fix double aortic arch. The surgeon ties off the smaller branch and separates it from the larger branch. Then the surgeon closes the ends of the aorta with stitches. This relieves pressure on the esophagus and windpipe.

  8. Aristotle and Double Effect

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2014-01-01

    cases from the literature on double effect such as, amongst others, strategic bombing, the trolley problem, and craniotomy. I find that, despite some common features such as the dilemmatic structure and the inevitability of a bad effect, Aristotle’s mixed actions do not count as cases justifiable...

  9. Nuclear double beta decay

    International Nuclear Information System (INIS)

    Hubert, P.; Mennrath, P.

    1985-01-01

    The processes of double beta decay with and without emission of neutrinos are briefly reviewed. After the definitions of the processes and implications for the neutrino properties, the present status of the experimental results is discussed. We conclude with a description of the Bordeaux-Zaragoza-Strasbourg experimental which will run in the Frejus tunnel

  10. Aristotle and Double Effect

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2014-01-01

    There are some interesting similarities between Aristotle’s ‘mixed actions’ in Book III of the Nicomachean Ethics and the actions often thought to be justifiable with the Doctrine of Double Effect. Here I analyse these similarities by comparing Aristotle’s examples of mixed actions with standard ...

  11. Tube Formation in Nanoscale Materials

    Directory of Open Access Journals (Sweden)

    Yan Chenglin

    2008-01-01

    Full Text Available Abstract The formation of tubular nanostructures normally requires layered, anisotropic, or pseudo-layered crystal structures, while inorganic compounds typically do not possess such structures, inorganic nanotubes thus have been a hot topic in the past decade. In this article, we review recent research activities on nanotubes fabrication and focus on three novel synthetic strategies for generating nanotubes from inorganic materials that do not have a layered structure. Specifically, thermal oxidation method based on gas–solid reaction to porous CuO nanotubes has been successfully established, semiconductor ZnS and Nb2O5nanotubes have been prepared by employing sacrificial template strategy based on liquid–solid reaction, and an in situ template method has been developed for the preparation of ZnO taper tubes through a chemical etching reaction. We have described the nanotube formation processes and illustrated the detailed key factors during their growth. The proposed mechanisms are presented for nanotube fabrication and the important pioneering studies are discussed on the rational design and fabrication of functional materials with tubular structures. It is the intention of this contribution to provide a brief account of these research activities.

  12. Tube Formation in Nanoscale Materials.

    Science.gov (United States)

    Yan, Chenglin; Liu, Jun; Liu, Fei; Wu, Junshu; Gao, Kun; Xue, Dongfeng

    2008-12-01

    The formation of tubular nanostructures normally requires layered, anisotropic, or pseudo-layered crystal structures, while inorganic compounds typically do not possess such structures, inorganic nanotubes thus have been a hot topic in the past decade. In this article, we review recent research activities on nanotubes fabrication and focus on three novel synthetic strategies for generating nanotubes from inorganic materials that do not have a layered structure. Specifically, thermal oxidation method based on gas-solid reaction to porous CuO nanotubes has been successfully established, semiconductor ZnS and Nb(2)O(5) nanotubes have been prepared by employing sacrificial template strategy based on liquid-solid reaction, and an in situ template method has been developed for the preparation of ZnO taper tubes through a chemical etching reaction. We have described the nanotube formation processes and illustrated the detailed key factors during their growth. The proposed mechanisms are presented for nanotube fabrication and the important pioneering studies are discussed on the rational design and fabrication of functional materials with tubular structures. It is the intention of this contribution to provide a brief account of these research activities.

  13. Atmosphere in a Test Tube

    Science.gov (United States)

    Claudi, R.; Pace, E.; Ciaravella, A.; Micela, G.; Piccioni, G.; Billi, D.; Cestelli Guidi, M.; Coccola, L.; Erculiani, M. S.; Fedel, M.; Galletta, G.; Giro, E.; La Rocca, N.; Morosinotto, T.; Poletto, L.; Schierano, D.; Stefani, S.

    The ancestor philosophers' dream of thousand of new world is finally realised: more than 1800 extrasolar planets have been discovered in the neighborhood of our Sun. Most of them are very different from those we used to know in our Solar System. Others orbit the Habitable Zone (HZ) of their parent stars. Space missions, as JWST and the very recently proposed ARIEL, or ground based instruments, like SPHERE@VLT, GPI@GEMINI and EPICS@ELT, have been proposed and built to measure the atmospheric transmission, reflection and emission spectra over a wide wavelength range of these new worlds. In order to interpret the spectra coming out by this new instrumentation, it is important to know in detail the optical characteristics of gases in the typical physical conditions of the planetary atmospheres and how those characteristics could be affected by radiation driven photochemical and bio-chemical reaction. Insights in this direction can be achieved from laboratory studies of simulated planetary atmosphere of different pressure and temperature conditions under the effects of radiation sources, used as proxies of different bands of the stellar emission. ''Atmosphere in a Test Tube'' is a collaboration among several Italian astronomical, biological and engineering institutes in order to share their experiencece in performing laboratory experiments on several items concerning extrasolar planet atmospheres.

  14. Ultrasonography for confirmation of gastric tube placement.

    Science.gov (United States)

    Tsujimoto, Hiraku; Tsujimoto, Yasushi; Nakata, Yukihiko; Akazawa, Mai; Kataoka, Yuki

    2017-04-17

    Gastric tubes are commonly used for the administration of drugs and tube feeding for people who are unable to swallow. Feeding via a tube misplaced in the trachea can result in severe pneumonia. Therefore, the confirmation of tube placement in the stomach after tube insertion is important. Recent studies have reported that ultrasonography provides good diagnostic accuracy estimates in the confirmation of appropriate tube placement. Hence, ultrasound could provide a promising alternative to X-rays in the confirmation of tube placement, especially in settings where X-ray facilities are unavailable or difficult to access. To assess the diagnostic accuracy of ultrasound for gastric tube placement confirmation. We searched the Cochrane Library (2016, Issue 3), MEDLINE (to March 2016), Embase (to March 2016), National Institute for Health Research (NIHR) PROSPERO Register (to May 2016), Aggressive Research Intelligence Facility Databases (to May 2016), ClinicalTrials.gov (to May 2016), ISRCTN registry (May 2016), World Health Organization International Clinical Trials Registry Platform (to May 2016) and reference lists of articles, and contacted study authors. We included studies that evaluated the diagnostic accuracy of naso- and orogastric tube placement confirmed by ultrasound visualization using X-ray visualization as the reference standard. We included cross-sectional studies, and case-control studies. We excluded case series or case reports. Studies were excluded if X-ray visualization was not the reference standard or if the tube being placed was a gastrostomy or enteric tube. Two review authors independently assessed the risk of bias and extracted data from each of the included studies. We contacted authors of the included studies to obtain missing data. We identified 10 studies (545 participants and 560 tube insertions) which met our inclusion criteria.No study was assigned low risk of bias or low concern in every QUADAS-2 domain. We judged only three (30

  15. Resonant oscillations in open axisymmetric tubes

    Science.gov (United States)

    Amundsen, D. E.; Mortell, M. P.; Seymour, B. R.

    2017-12-01

    We study the behaviour of the isentropic flow of a gas in both a straight tube of constant cross section and a cone, open at one end and forced at or near resonance at the other. A continuous transition between these configurations is provided through the introduction of a geometric parameter k associated with the opening angle of the cone where the tube corresponds to k=0. The primary objective is to find long-time resonant and near-resonant approximate solutions for the open tube, i.e. k→ 0. Detailed analysis for both the tube and cone in the limit of small forcing (O(ɛ 3)) is carried out, where ɛ 3 is the Mach number of the forcing function and the resulting flow has Mach number O(ɛ ). The resulting approximate solutions are compared with full numerical simulations. Interesting distinctions between the cone and the tube emerge. Depending on the damping and detuning, the responses for the tube are continuous and of O(ɛ ). In the case of the cone, the resonant response involves an amplification of the fundamental resonant mode, usually called the dominant first-mode approximation. However, higher modes must be included for the tube to account for the nonlinear generation of higher-order resonances. Bridging these distinct solution behaviours is a transition layer of O(ɛ 2) in k. It is found that an appropriately truncated set of modes provides the requisite modal approximation, again comparing well to numerical simulations.

  16. Carburization of stainless steel furnace tubes

    Energy Technology Data Exchange (ETDEWEB)

    Mirabal, E.; Molina, C. [Refineria Isla, Curazao, S.A., P.O. Box 3843. Curacao, (Netherlands Antilles); Hau, J.L.; Mayorga, A.G. [PDVSA-Intevep. P.O. Box 76343. Caracas 1070A, Venezuela (Venezuela)

    1998-12-31

    Stainless steel containing molybdenum are usually recommended to resist naphtenic acid corrosion in vacuum heaters. In 1993 the original 5Cr-1/2Mo roof tubes of the furnace in a vacuum unit were replaced by stainless steel 316 Ti to minimize tube replacement and increase heater reliability. Unexpectedly, some of the new tubes failed after only three years of service and just one year after undergoing the last inspection. The damage occurred in the form of deep holes and perforations, starting from the outside tube surface on the fireside. Coke build-up occurred due to severe operating conditions, overheating the tubes on the fireside, above 675 Centigrade. Metallographic and Scanning Electron Microscopy (Sem) examination revealed internal and external carburization of the material due to the presence of coke and combustion ashes, respectively. The increase in the skin metal temperature facilitated the diffusion of carbon from these carbon-rich deposits into the low carbon content material (0.023%). Depletion of chromium at the grain boundaries due to the massive formation of chromium carbides, resulted in a severe intergranular corrosion attack by molten salts rich in vanadium and sulfur produced by asphalt burning. Normal operating practice demands the use of steam for the heater tubes to control coke build-up. This practice had been first reduced and then eliminated, during the past two years prior to the failure, because of economic incentives. This paper describes the root cause analysis conducted to account for these premature tube failures. (Author)

  17. Carburization of stainless steel furnace tubes

    International Nuclear Information System (INIS)

    Mirabal, E.; Molina, C.; Hau, J.L.; Mayorga, A.G.

    1998-01-01

    Stainless steel containing molybdenum are usually recommended to resist naphtenic acid corrosion in vacuum heaters. In 1993 the original 5Cr-1/2Mo roof tubes of the furnace in a vacuum unit were replaced by stainless steel 316 Ti to minimize tube replacement and increase heater reliability. Unexpectedly, some of the new tubes failed after only three years of service and just one year after undergoing the last inspection. The damage occurred in the form of deep holes and perforations, starting from the outside tube surface on the fireside. Coke build-up occurred due to severe operating conditions, overheating the tubes on the fireside, above 675 Centigrade. Metallographic and Scanning Electron Microscopy (Sem) examination revealed internal and external carburization of the material due to the presence of coke and combustion ashes, respectively. The increase in the skin metal temperature facilitated the diffusion of carbon from these carbon-rich deposits into the low carbon content material (0.023%). Depletion of chromium at the grain boundaries due to the massive formation of chromium carbides, resulted in a severe intergranular corrosion attack by molten salts rich in vanadium and sulfur produced by asphalt burning. Normal operating practice demands the use of steam for the heater tubes to control coke build-up. This practice had been first reduced and then eliminated, during the past two years prior to the failure, because of economic incentives. This paper describes the root cause analysis conducted to account for these premature tube failures. (Author)

  18. The Effect of Local Electric Field in the Middle Dielectric Wall on the Infrared Plasmonic Shift of the Concentric Gold Double Nanotubes.

    Science.gov (United States)

    Zhenji, Li; Shaoyan, Gao

    2015-02-01

    The effect of inserted gold nanotube on the localized surface plasmon resonance (LSPR) shifting and local electric field enhancement of concentric gold double nanotubes has been studied by using the quasi-static electricity. Because of the combined effect from inter-surface and inter-tube plasmon coupling, the LSPR in gold double nanotubes could be easily tuned into the infrared wavelength region. The calculation results indicate the plasmon peak shifting is quite sensitive to the thickness of the inner gold tube and the gap between the inner and outer gold tubes. The physical mechanism has been attributed to the local field effect of the separate dielectric layer. Because of the additional attraction from the inner gold tube to the free electrons at outer gold tube, the decreasing electric field in the middle dielectric spacer layer reduces the restoring force and lead to intense red shift of LSPR.

  19. Ceramic accelerating tube of the improved construction

    International Nuclear Information System (INIS)

    Vasserman, S.B.; Kazarezov, I.V.; Pokhlebenin, E.I.; Shirokov, V.V.

    1976-01-01

    An improved ceramic accelerating tube is designed. The electrodes are made of copper and covar which provides for maintaining the geometry of the electrodes at thermal-compression welding and obviates the need for machanical treatment of the envelope after welding. Employment of the insulators with a finned surface from the vacuum side by two times increases the electric strength of the accelerating tube, as compared to the insulators with a smooth surface. The accelerating tube envelope can withstand the pulsed voltages of 1.5 MV at a pulse duration of 6 μs and a repetition rate of 100 Hz within two hours

  20. X-ray tube technology update

    International Nuclear Information System (INIS)

    Rehani, M.M.

    1997-01-01

    During the 100 years since the discovery of x-rays, the x-ray tube has undergone significant improvements to meet the demand of shorter exposure time and frequent exposures as in angiography. This has been achieved by multiple focal spots, rotating anodes, design consideration of the anode and the tube assembly. While physical improvements have resulted in improved performance, the principle has remained the same, as also has the problem of massive heat generation which consumes almost 99% of the energy. This article traces the history of tubes and current perspectives. (author). 3 refs., 3 figs., 2 tabs

  1. Autocalibration of high precision drift tubes

    International Nuclear Information System (INIS)

    Bacci, C.; Bini, C.; Ciapetti, G.; De Zorzi, G.; Gauzzi, P.; Lacava, F.; Nisati, A.; Pontecorvo, L.; Rosati, S.; Veneziano, S.; Cambiaghi, M.; Casellotti, G.; Conta, C.; Fraternali, M.; Lanza, A.; Livan, M.; Polesello, G.; Rimoldi, A.; Vercesi, V.

    1997-01-01

    We present the results on MDT (monitored drift tubes) autocalibration studies obtained from the analysis of the data collected in Summer 1995 on the H8B Muon Test Beam. In particular we studied the possibility of autocalibration of the MDT using four or three layers of tubes, and we compared the calibration obtained using a precise external tracker with the output of the autocalibration procedure. Results show the feasibility of autocalibration with four and three tubes and the good accuracy of the autocalibration procedure. (orig.)

  2. Noninflammatory fallopian tube pathology in children

    International Nuclear Information System (INIS)

    Merlini, Laura; Anooshiravani, Mehrak; Hanquinet, Sylviane; Vunda, Aaron; Borzani, Irene; Napolitano, Marcello

    2008-01-01

    Noninflammatory tubal abnormalities are rare in children and usually not well covered by traditional educational material. The presenting symptoms are nonspecific and are common to many other conditions, so its preoperative diagnosis is rarely made. The purpose of this study was to review the hospital charts and imaging findings in children and sexually inactive adolescents who showed fallopian tube pathology. Understanding of the pertinent findings of previous imaging examinations might assist radiologists in making the correct preoperative diagnosis and increase the likelihood of preserving the fallopian tubes. The clinical entities described in this article include isolated tubal torsion, paratubal cysts, hydrosalpinx, undescended/ectopic fallopian tube, and tubal inguinal hernia. (orig.)

  3. CATHENA Code Assessment for Pressure Tube and Calandria Tube Contact Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hyoung Kyoun; Choi, Chul Jin; Choi, Jong Ho [KEPCO-EnC, Daejeon (Korea, Republic of)

    2015-05-15

    Canadian Algorithm for THErmalhydraulic Network Analysis (CATHENA), has been validated against full-scale Contact Boiling Experiments conducted using specific channel power, pressure, and moderator subcooling as pre-test conditions. The pressure tube (PT) and calandria tube (CT) temperatures, the extent of dryout and failures of the pressure tube or the calandria tube (if any) are the outcome of these experiments. Recently, an IAEA International Collaborative Standard Problem (ICSP) to provide contact boiling experimental data to participants for assessing the subcooling requirements for a heated pressure tube, plastically deforming into contact with the calandria tube during a postulated large break LOCA condition has been performed. The CATHENA code assessment results against the experimental data distributed for the ICSP are provided in this paper. The CATHENA code is used to simulate the experiment on pressure tube ballooning conducted at the AECL. The overall code's predictions show good agreements with the experimental data. The contact timing by the pressure tube ballooning is predicted accurately, however, it is found that the code largely underpredict the peak temperature at the pressure tube and the calandria tube. This discrepancy seems to be induced from multi-dimensional flow effects in the water tank. For more accurate calculations, detailed modeling of the water tank is required.

  4. A prospective randomized trial of transnasal ileus tube vs nasogastric tube for adhesive small bowel obstruction

    Science.gov (United States)

    Chen, Xiao-Li; Ji, Feng; Lin, Qi; Chen, Yi-Peng; Lin, Jian-Jiang; Ye, Feng; Yu, Ji-Ren; Wu, Yi-Jun

    2012-01-01

    AIM: To study the therapeutic efficacy of a new transnasal ileus tube advanced endoscopically for adhesive small bowel obstruction. METHODS: A total of 186 patients with adhesive small bowel obstruction treated from September 2007 to February 2011 were enrolled into this prospective randomized controlled study. The endoscopically advanced new ileus tube was used for gastrointestinal decompression in 96 patients and ordinary nasogastric tube (NGT) was used in 90 patients. The therapeutic efficacy was compared between the two groups. RESULTS: Compared with the NGT group, the ileus tube group experienced significantly shorter time for relief of clinical symptoms and improvement in the findings of abdominal radiograph (4.1 ± 2.3 d vs 8.5 ± 5.0 d) and laboratory tests (P tube group and 46.7% in the NGT group (P tube group and 53.3% of the NGT group underwent surgery. For recurrent adhesive bowel obstruction, ileus tube was also significantly more effective than NGT (95.8% vs 31.6%). In the ileus tube group, the drainage output on the first day and the length of hospital stay were significantly different depending on the treatment success or failure (P tube can be used for adhesive small bowel obstruction. Endoscopic placement of the ileus tube is convenient and worthy to be promoted despite the potential risks. PMID:22563179

  5. Gastrostomy Tube Placement Without Nasogastric Tube: A Retrospective Evaluation in 85 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Heberlein, Wolf E., E-mail: weheberlein@uams.edu; Goodwin, Whitney J.; Wood, Clint E.; Yousaf, Muhammad; Culp, William C. [University of Arkansas for Medical Sciences, Department of Radiology (United States)

    2012-12-15

    Purpose: Our study evaluated techniques for percutaneous gastrostomy (G)-tube placement without the use of a nasogastric (NG) tube. Instead, direct puncture of a physiologic air bubble or effervescent-enhanced gastric bubble distention was performed in patients with upper digestive tract obstruction (UDTO) or psychological objections to NG tubes. Materials and Methods: A total of 886 patients underwent G-tube placement in our department during a period of 7 years. We present our series of 85 (9.6%) consecutive patients who underwent percutaneous G-tube placement without use of an NG tube. Results: Of these 85 patients, fluoroscopic guided access was attempted by direct puncture of a physiologically present gastric air bubble in 24 (28%) cases. Puncture of an effervescent-induced large gastric air bubble was performed in 61 (72%) patients. Altogether, 82 (97%) of 85 G tubes were successfully placed in this fashion. The three failures comprised refusal of effervescent, vomiting of effervescent, and one initial tube misplacement when a deviation from our standard technique occurred. Conclusion: The described techniques compare favorably with published large series on G-tube placement with an NG tube in place. The techniques are especially suited for patients with UDTO due to head, neck, or esophageal malignancies, but they should be considered as an alternative in all patients. Direct puncture of effervescent-enhanced gastric bubble distention is a safe, patient-friendly and effective technique.

  6. Influence of furnace tube shapeon thermal strain of fire-tube boilers

    Directory of Open Access Journals (Sweden)

    Gaćeša Branka

    2014-01-01

    Full Text Available The aim of this paper is to use numerical analysis and fine element method-FEM to investigate the influence of furnace tube shape on the thermal strain of fire-tube boilers. Thermal stresses in corrugated furnace tubes of different shape, i.e. with different corrugation pitch and depth, were analysed first. It was demonstrated that the thermal stresses in corrugated furnace tube are significantly reduced with the increase of corrugation depth. Than deformations and stresses in the structure of a fire-tube boiler were analysed in a real operating condition, for the cases of installed plain furnace tube and corrugated furnace tubes with different shapes. It was concluded that in this fire-tube boiler, which is of larger steam capacity, the corrugated furnace tube must be installed, as well as that the maximal stress in the construction is reduced by the installation of the furnace tube with greater corrugation depth. The analysis of stresses due to pressure and thermal loads pointed out that thermal stresses are not lower-order stresses in comparison to stresses due to pressure loads, so they must be taken into consideration for boiler strength analysis. [Projekat Ministarstva nauke Republike Srbije, br. TR 35040 i br. TR 35011

  7. Procedure and device for extracting the end of a tube inserted into a hole in a tube plate

    International Nuclear Information System (INIS)

    1980-01-01

    When constructing heat exchangers and steam generators, particularly in the construction of steam generators for nuclear power stations, many small diameter tubes have to be secured into a very thick tube plate for instance 600 mm thick. This crimping or expanding of the tube is generally performed by rolling the internal surface of the tube inside a hole drilled right through the tube plate and slightly greater in diameter than the external diameter of the tube before the tube is rolled. To check the tubes for defects, it is necessary to extract certain tubes from the tube plate in order to move the tube to a testing and inspection point and examine the part of it that was secured in the plate hole. The invention concerns the uncrimping of these tubes [fr

  8. EFFECT OF TUBE PITCH ON HEAR TRANSFER IN SPRINKLED TUBE BUNDLE

    Directory of Open Access Journals (Sweden)

    Petr Kracík

    2015-10-01

    Full Text Available Water flowing on a sprinkled tube bundle forms three basic modes: the Droplet mode (the liquid drips from one tube to another, the Jet mode (with an increasing flow rate, the droplets merge into a column and the Membrane (Sheet mode (with a further increase in the flow rate of the falling film liquid, the columns merge and create sheets between the tubes. With a sufficient flow rate, the sheets merge at this stage, and the tube bundle is completely covered by a thin liquid film. There are several factors influencing both the individual modes and the heat transfer. Beside the above-mentioned falling film liquid flow rate, these are for instance the tube diameters, the tube pitches in the tube bundle, or the physical conditions of the falling film liquid. This paper presents a summary of data measured at atmospheric pressure, with a tube bundle consisting of copper tubes of 12 millimetres in diameter, and with a studied tube length of one meter. The tubes are situated horizontally one above another at a pitch of 15 to 30 mm, and there is a distribution tube placed above them with water flowing through apertures of 1.0mm in diameter at a 9.2mm span. Two thermal conditions have been tested with all pitches: 15 °C to 40 °C and 15 °C to 45 °C. The temperature of the falling film liquid, which was heated during the flow through the exchanger, was 15 °C at the distribution tube input. The temperature of the heating liquid at the exchanger input, which had a constant flow rate of approx. 7.2. litres per minute, was 40 °C, or alternatively 45 °C.

  9. Evaluation of neutron streaming in fast breeder reactor fuel assembly by double heterogeneous modelling

    International Nuclear Information System (INIS)

    Unesaki, Hironobu; Takeda, Toshikazu

    1988-01-01

    Neutron streaming in a fast breeder reactor fuel assembly caused by the double heterogeneity structure is estimated by double heterogeneous modelling. The conventional pin cell model, a two-region subassembly model and the exact pin cluster model are used to take into account the streaming effect caused by the pin cell structure and the surrounding wrapper tube structure. The heterogeneity of wrapper tube and its surrounding sodium is explicitly considered. The streaming effect is evaluated based on Benoist's diffusion coefficient. The total streaming effect caused by the double heterogeneity structure of a fuel subassembly is found to be -0.2 % dk/kk' for k eff , which is almost twice that obtained from the conventional pin cell model of -0.1 % dk/kk'. (author)

  10. Double-walled ZrO{sub 2} nanotube array. Preparation and enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Chaorui; Hu, Shengliang; Chang, Qing; Wang, Yanzhong [School of Materials Science and Engineering, North University of China, Taiyuan (China); Yang, Jinlong [School of Materials Science and Engineering, North University of China, Taiyuan (China); School of Materials Science and Engineering, Tsinghua University, Beijing (China)

    2017-11-15

    This work demonstrates the formation of self-ordered double-walled ZrO{sub 2} nanotube array via electrochemical anodization in glycerol-based electrolyte. Compared with its counterpart of single-walled ZrO{sub 2} nanotube array, the tube wall of double-walled ZrO{sub 2} nanotube split into outer and inner layers for the decomposition of glycerol during anodization process. Moreover, the double-walled structure showed its advantage of achieving improved utilization of light and higher specific surface area of nanotube array. Due to the unique double-walled structure, the double-walled ZrO{sub 2} nanotube array exhibited better photocatalytic activity than the single-walled ZrO{sub 2} nanotube array. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Project Half Double

    DEFF Research Database (Denmark)

    Svejvig, Per; Gerstrøm, Anna; Frederiksen, Signe Hedeboe

    projects and to document their development. The purpose of this addendum is thus to document the development in the pilot projects from June 2016 to January 2017 with particular focus on the impact they have created. This Addendum is a supplement and should be read in conjunction with the Phase 1 report...... by the day. The formal part of Project Half Double was initiated in June 2015; it is divided into two phases where phase 1 took place from June 2015 to June 2016 with seven pilot projects, and phase 2 is in progress from July 2016 to July 2017 with 10 pilot projects. The Half Double consortium: Implement....... The Danish Industry Foundation, an independent philanthropic foundation, is contributing to the project financially with DKK 13.8 million. About the addendum: We published the report “Preliminary results for phase 1” in June 2016 (Svejvig, Ehlers et al. 2016). It is time to follow up on the Phase 1 pilot...

  12. The double Laplacian growth

    International Nuclear Information System (INIS)

    Loutsenko, I.; Yermolayeva, O.

    2008-06-01

    The dynamics of the idealized Laplacian growth (or the Hele-Shaw problem) can be approximated by the Poiselle flow which in appropriate units takes the form of the Darcy law. In this paper we account for the liquid inertia in the Hele-Shaw problem at zero surface tension limit. The Laplace dynamics for the pressure is extended here with one more for the velocity potential for which we call this growth process the Double Laplacian. The application of the conformal mappings technique leads to doubled dynamics for both the conformal map and the complex potential, which is presented in the paper for the radial and the planar growth. We apply the stability analysis and discuss the integrability for the stated problem. (author)

  13. Subatmospheric double containment system

    International Nuclear Information System (INIS)

    Gans, D. Jr.; Noble, J.H.

    1978-01-01

    A reinforced concrete double wall nuclear containment structure with each wall including an essentially impervious membrane or liner and porous concrete filling the annulus between the two walls is described. The interior of the structure is maintained at subatmospheric pressure, and the annulus between the two walls is maintained at a subatmospheric pressure intermediate between that of the interior and the surrounding atmospheric pressure, during normal operation. In the event of an accident within the containment structure the interior pressure may exceed atmospheric pressure, but leakage from the interior to the annulus between the double walls will not result in the pressure of the annulus exceeding atmospheric pressure so that there is no net outleakage from the containment structure

  14. Neutrinoless double beta decay

    Indian Academy of Sciences (India)

    2012-10-06

    Oct 6, 2012 ... nuclear decay of neutrinoless double beta decay typically leading to sub-eV values as well. (Z, A) → (Z + 2, A) + 2e .... Here again energy resolution matters, because of the continuous spectrum of the 2νββ- decay mode, its high .... The benefit of using Te is its high natural abundance. This experiment is in ...

  15. Internal ultrasonic testing of steam generator tubes

    International Nuclear Information System (INIS)

    Furlan, J.; Soleille, G.; Chalaye, H.

    1983-01-01

    The ''in situ'' inspection of steam generator tubes uses generally Foucault currents before starting and along its life. This inspection aims at searching cracks and corrosion defects. The Foucault current method is quite badly adapted to ''closed crack'' detection, for it doesn't introduce neither resistivity or magnetic permeability variation, or lack of matter. More, it is sensible to the magnetic properties of the tube itself and to its environment (tubular or support plates). It is why, this first systematic inspection has to be completed by an ultrasonic one allowing to bring new elements in the uncertain cases. A device with an internal probe has been developed. It ''lights'' the tube wall with the aid of a transducer of which beam reflects on a mirror. Operating conditions are the same as for Foucault current testing, that is to say the probe moves inside the tube without rotation of the device (bent parts are excluded) [fr

  16. YouTube and ‘psychiatry’

    Science.gov (United States)

    Gordon, Robert; Miller, John; Collins, Noel

    2015-01-01

    YouTube is a video-sharing website that is increasingly used to share and disseminate health-related information, particularly among younger people. There are reports that social media sites, such as YouTube, are being used to communicate an anti-psychiatry message but this has never been confirmed in any published analysis of YouTube clip content. This descriptive study revealed that the representation of ‘psychiatry’ during summer 2012 was predominantly negative. A subsequent smaller re-analysis suggests that the negative portrayal of ‘psychiatry’ on YouTube is a stable phenomenon. The significance of this and how it could be addressed are discussed. PMID:26755987

  17. Integrity Assessment of GOH Heater Tube

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Bong Sang; Hong, J. H.; Oh, Y. J.; Yoon, J. H.; Oh, J. M. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1997-08-01

    An assessment of structural integrity of ASTM A312-TP347 GOH heater tube was performed. The surface notches which had been produced during tube manufacturing process were analyzed microscopically. Chemical analysis, hardness tests, tensile tests, and J-Integral fracture resistance tests were carried out to compare the mechanical properties with those of the material specification and also with the other material of the same type. The test results showed the mechanical properties of the GOH tube material are within the specification range. An elastic-plastic fracture mechanics analysis based on the DPFAD method reveals the tube an appropriate safety margin for the normal operation. 13 refs., 5 tabs., 24 figs. (author)

  18. Medical Informatics Idle YouTube Potential.

    Science.gov (United States)

    Hucíková, Anežka; Babic, Ankica

    2017-01-01

    YouTube as an online video-sharing service in the context of Web 2.0 goes beyond the bounds of pure fun, for which the platform was primarily established. Nowadays, commonly to other social media, it serves also educational, informational and last but not least, marketing purposes. The importance of video sharing is supported by several predictions about video reaching over 90% of global internet traffic by 2020. Using qualitative content analysis over selected YouTube videos, paper examines the current situation of the platform's marketing potential usage by medical informatics organizations, researches and other healthcare professionals. Results of the analysis demonstrate several ways in which YouTube is already used to inform, educate or promote above-mentioned medical institutions. However, their engagement in self-promo or spreading awareness of their research projects via YouTube is considered to be low.

  19. Energy absorber uses expanded coiled tube

    Science.gov (United States)

    Johnson, E. F.

    1972-01-01

    Mechanical shock mitigating device, based on working material to its failure point, absorbs mechanical energy by bending or twisting tubing. It functions under axial or tangential loading, has no rebound, is area independent, and is easy and inexpensive to build.

  20. Advanced Illness: Feeding Tubes and Ventilators

    Science.gov (United States)

    ... are here Home Advanced Illness: Feeding Tubes and Ventilators Order this publication Printer-friendly version Introduction Families ... a Family Meeting for additional help. Pneumonia and Ventilators One of the other choices a patient or ...

  1. SPECIAL PURPOSE SHOCK TUBE for BLAST ASSESSMENT

    Data.gov (United States)

    Federal Laboratory Consortium — This device is a specially designed shock tube for testing fabric samples in a controlled environment. The device determines the appropriate types of sensors to be...

  2. The nasogastric tube syndrome in infants.

    Science.gov (United States)

    Harmon, Jeffrey; Balakrishnan, Karthik; de Alarcon, Alessandro; Hart, Catherine K

    2014-05-01

    This series of three patients is the first description of the presentation, clinical course, and endoscopic findings of nasogastric tube-related airway distress, or nasogastric tube syndrome, in infants. We identify key differences in disease features from those described in adults, based on our literature review. Specifically, infant nasogastric tube syndrome presented as significant respiratory distress and postcricoid inflammation without vocal fold immobility. Symptoms resolved more quickly (mean±SD, 2±1 days) than reported in adults. We suggest that nasogastric tube syndrome should be considered in infants with otherwise unexplained respiratory distress, even in the absence of impaired vocal fold mobility. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. Short Communication Tube-forming polychaetes enhance ...

    African Journals Online (AJOL)

    bottom systems in the North Atlantic where polychaete tube densities are often much higher. Keywords: habitat formation, onuphid polychaete, species richness, western Indian Ocean African Journal of Marine Science 2011, 33(2): 327–332 ...

  4. Accidental Decannulation OF TRACHEOSTOMY TUBES - Case Series.

    Science.gov (United States)

    Omokanye, H K; Dunmade, A D; Segun-Busari, S; Afolabi, O A; Habeeb, O G; Adegboye, M B; Alabi, B S

    2016-01-01

    Tracheostomy tube (TT) is usually removed in a planned manner once the patient ceases to have the condition that necessitated the procedure. Accidental decannulation or extubation refers to inadvertent removal of tracheostomy tube out of the stoma. It could prove fatal in an otherwise stable patient. We review a variety of unexpected and often-overlooked causes of accidental decannulation with suggestions on preventive measures. We therefore present three cases of accidental decannulation of tracheostomy tubes in order to report our experiences in the management of the condition. Accidental decannulation occurs both in hospitalized and patient on home care of their tracheostomy tubes. Reduction in neck circumference due to weight loss predisposes to accidental decannulation, which could be prevented by suturing the flange to the skin.

  5. A simplified technique for nasoendotracheal tube immobilization.

    OpenAIRE

    Berardo, N.; Leban, S. G.; Williams, F. A.

    1989-01-01

    A simplified technique for immobilization of a nasoendotracheal tube is described in which a wide strap of open cell, hypoallergenic, foam-backed fabric is secured to the patient's head with a Velcro fastener.

  6. Manufacturing and testing the HTGR refueling tube

    International Nuclear Information System (INIS)

    Gurin, V.A.; Gribanov, Yu.A.; Kolosenko, V.V.; Gujda, V.V.

    2015-01-01

    The paper describes the manufacturing technique for a refueling tube of a high-temperature gas-cooled nuclear reactor (HTGR). Four refueling tube sections were made: two sections from GSP-50 material and two sections from carbon-carbon (C-C) composite materials. Radiation tests were carried out in the reactor BOR-60. Experimental results show that the strength characteristics and thermophysical properties of graphitized carbon materials, from which the sections have been manufactured, are higher by a factor of 2.5-3.5 as compared with the HTGR refueling tube requirements. The dimensional changes of GSP-50 and C-C composite materials at temperatures between 300 and 600 deg C up to the neutron fluence of 1·10 21 n/cm 2 are comparable and meet the specifications for HTGR refueling tube

  7. Stabilization Strategies for Drift Tube Linacs

    CERN Document Server

    AUTHOR|(CDS)2085420; Lamehi Rashti, Mohammad

    The average axial electric fields in drift tube linac cavities are known to be sensitive with respect to the perturbation errors. Postcoupler is a powerful stabilizer devices that is used to reduce this sensitivity of average axial field. Postcouplers are the cylindrical rod which is extended from cavity wall toward the drift tube without touching the drift tube surface. Postcouplers need to be adjusted to the right length to stabilize the average axial field. Although postcouplers are used successfully in many projects, there is no straightforward procedure for postcouplers adjustment and it has been done almost based on trial and errors. In this thesis, the physics and characteristics of postcouplers has been studied by using an equivalent circuit model and 3D finite element method calculations. Finally, a straightforward and accurate method to adjust postcouplers has been concluded. The method has been verified by using experimental measurements on CERN Linac4 drift tube linac cavities.

  8. Flux Tube Dynamics in the Dual Superconductor

    International Nuclear Information System (INIS)

    Lampert, M.; Svetitsky, B.

    1999-01-01

    We have studied plasma oscillations in a flux tube created in a dual superconductor. The theory contains an Abelian gauge field coupled magnetically to a Higgs field that confines electric charge via the dual Meissner effect. Starting from a static flux tube configuration, with electric charges at either end, we release a fluid of electric charges in the system that accelerate and screen the electric field. The weakening of the electric field allows the flux tube to collapse, and the inertia of the charges forces it open again. We investigate both Type I and Type II superconductors, with plasma frequencies both above and below the threshold for radiation into the Higgs vacuum. (The parameters appropriate to QCD are in the Type II regime; the plasma frequency depends on the mass taken for the fluid constituents.) The coupling of the plasma oscillations to the Higgs field making up the flux tube is the main new feature in our work

  9. The Choking Game on YouTube

    Science.gov (United States)

    Defenderfer, Ellen K.; Austin, Jillian E.; Davies, W. Hobart

    2016-01-01

    The choking game (TCG) is an adolescent activity in which asphyxiation is used to obtain a “high,” occasionally resulting in seizures or death. A plethora of TCG information is available through YouTube, though this content has not been evaluated recently. The current study described TCG as portrayed in YouTube videos and compared views and ratings of TCG videos to unrelated videos. The TCG videos demonstrated diverse methods of asphyxiation, with a minority showing injury to the participants. TCG videos were less likely to be commented on or rated positively than non–choking game videos. TCG prevention videos differed significantly from actual TCG videos in the way they depicted the social context of TCG. Thus, TCG videos are accessible through YouTube, but the prevention materials available on YouTube are not accurate or representative. Accurate and educational online prevention materials should be created to decrease the occurrence of TCG. PMID:27335992

  10. The Choking Game on YouTube

    Directory of Open Access Journals (Sweden)

    Ellen K. Defenderfer MS

    2016-03-01

    Full Text Available The choking game (TCG is an adolescent activity in which asphyxiation is used to obtain a “high,” occasionally resulting in seizures or death. A plethora of TCG information is available through YouTube, though this content has not been evaluated recently. The current study described TCG as portrayed in YouTube videos and compared views and ratings of TCG videos to unrelated videos. The TCG videos demonstrated diverse methods of asphyxiation, with a minority showing injury to the participants. TCG videos were less likely to be commented on or rated positively than non–choking game videos. TCG prevention videos differed significantly from actual TCG videos in the way they depicted the social context of TCG. Thus, TCG videos are accessible through YouTube, but the prevention materials available on YouTube are not accurate or representative. Accurate and educational online prevention materials should be created to decrease the occurrence of TCG.

  11. Inverse Kinematics of Concentric Tube Steerable Needles.

    Science.gov (United States)

    Sears, Patrick; Dupont, Pierre E

    2007-01-01

    Prior papers have introduced steerable needles composed of precurved concentric tubes. The curvature and extent of these needles can be controlled by the relative rotation and translation of the individual tubes. Under certain assumptions on the geometry and design of these needles, the forward kinematics problem can be solved in closed form by means of algebraic equations. The inverse kinematics problem, however, is not as straightforward owing to the nonlinear map between relative tube displacements and needle tip configuration as well as to the multiplicity of solutions as the number of tubes increases. This paper presents a general approach to solving the inverse kinematics problem using a pseudoinverse solution together with gradients of nullspace potential functions to enforce geometric and mechanical constraints.

  12. The effect of tube-support interaction on the dynamic response of heat exchanger tubes

    International Nuclear Information System (INIS)

    Shin, Y.S.; Jendrzejczyk, J.A.; Wambsganss, M.W.

    1977-01-01

    To avoid detrimental tube vibration in heat exchangers, resonant conditions and instabilitites must be avoided, and/or peak dynamic amplitudes must not exceed allowable limits. In attempting a theoretical analysis, questions arise as to the effects of tube/support interaction on tube vibrational characteristics (i.e. resonant frequencies, modes, damping) and response amplitude. As a part of ANL's Flow-Induced Vibration Program in support of the Clinch River Breeder Reactor Plant (CRBRP) steam generator design activity, tube/support interaction experiments are being performed not only to gain the insight into the dynamic behavior of CRBRP steam generator tubes, but also to provide the basis for developing design guidance. Test results were compared with anaytical results based on multispan tube with 'knife-edge' supports at the support locations. (Auth.)

  13. Chemical milling of zircaloy tubing to produce integral OD spiral finned tubes. AWBA development program

    Science.gov (United States)

    Horwood, W. A.

    1982-02-01

    A detailed process description is provided for producing integral spiral fins on the outside surface of Zircaloy nuclear fuel cladding tubes by masking with pressure sensitive tape strips and then chemical milling (pickling) the tube wall between the tape strips to leave the fins in relief. Fins up to 0.020 inch high by 0.05 to 0.12 inch wide were consistently produced on tubes having wall thickness of 0.008 inch or greater after fin pickling. Wall thickness uniformity was excellent. Information is provided on tube surface preparation to maximize tape mask adhesion time during pickling, acid chemistry control to prevent local tube wall thinning near the fin, and pickling techniques to promote uniform material removal. Simple fixture designs are described for quickly and conveniently applying the tape strips to the tube wall in an accurate spiral.

  14. Optimizing Tube Precurvature to Enhance Elastic Stability of Concentric Tube Robots.

    Science.gov (United States)

    Ha, Junhyoung; Park, Frank C; Dupont, Pierre E

    2017-02-01

    Robotic instruments based on concentric tube technology are well suited to minimally invasive surgery since they are slender, can navigate inside small cavities and can reach around sensitive tissues by taking on shapes of varying curvature. Elastic instabilities can arise, however, when rotating one precurved tube inside another. In contrast to prior work that considered only tubes of piecewise constant precurvature, we allow precurvature to vary along the tube's arc length. Stability conditions for a planar tube pair are derived and used to formulate an optimal design problem. An analytic formulation of the optimal precurvature function is derived that achieves a desired tip orientation range while maximizing stability and respecting bending strain limits. This formulation also includes straight transmission segments at the proximal ends of the tubes. The result, confirmed by both numerical and physical experiment, enables designs with enhanced stability in comparison to designs of constant precurvature.

  15. Cathode readout with stripped resistive drift tubes

    International Nuclear Information System (INIS)

    Bychkov, V.N.; Kekelidze, G.D.; Novikov, E.A.; Peshekhonov, V.D.; Shafranov, M.D.; Zhiltsov, V.E.

    1995-01-01

    A straw tube drift chamber prototype has been constructed and tested. The straw tube material is mylar film covered with a carbon layer with a resistivity of 0.5, 30 and 70 kΩ/□. Both the anode wire and the cathode strip signals were detected to study the behaviour of the chamber in the presence of X-ray ionization. The construction and the results of the study are presented. (orig.)

  16. A Flue Gas Tube for Thermoelectric Generator

    DEFF Research Database (Denmark)

    2013-01-01

    The invention relates to a flue gas tube (FGT) (1) for generation of thermoelectric power having thermoelectric elements (8) that are integrated in the tube. The FTG may be used in combined heat and power (CHP) system (13) to produce directly electricity from waste heat from, e.g. a biomass boiler....... The CHP system may also be operated in a heating or cooling mode, thus being able to heat or cool water by feeding electricity to the system....

  17. Fractional delay waveguide modeling of acoustic tubes

    Science.gov (United States)

    Vaelimaeki, V.

    The theme of this work is computational modeling of acoustic tubes. The models are intended to be used in a sound synthesizer based on physical modeling. Such a synthesizer could be used producing realistic sounds of, e.g., woodwind instruments or the human voice. This work deals with digital waveguide modeling of acoustic tubes, such as bores of musical woodwind instruments or the human vocal tract. The acoustic tube systems considered in this work are those consisting of a straight cylindrical or conical tube or of concatenated cylindrical or conical tube sections. Also, the joint of three tube sections is studied. Of special interest for our application is a junction where a side branch is connected to a cylindrical tube as it is needed in the simulation of finger holes of wood-wind instruments. All of the cylindrical tube models are described for both pressure and volume velocity. In the case of conical bores, only pressure waves are considered as models for volume velocity waves are more complicated. The basic waveguide models are extended by employing the concept of fractional delay, which means a delay smaller than a unit delay. The fractional delays are implemented using bandlimited interpolation. Applying fractional delay filtering techniques, a spatially discretized waveguide model is turned into a spatially continuous one. This implies that the length of the digital waveguide can be adjusted as accurately as required, and a change of the impedance of a waveguide may occur at any desired point between sampling points. The authors call this kind of system a fractional delay waveguide filter (FDWF). It is a discrete-time structure but a spatially continuous model of a physical system.

  18. Formability of Micro-Tubes in Hydroforming

    Science.gov (United States)

    Hartl, Christoph; Anyasodor, Gerald; Lungershausen, Joern

    2011-05-01

    Micro-hydroforming is a down-scaled metal forming process, based on the expansion of micro-tubes by internal pressurization within a die cavity. The objective of micro-hydroforming is to provide a technology for the economic mass production of complex shaped hollow micro-components. Influence of size effects in metal forming processes increases with scaling down of metal parts. Investigations into the change in formability of micro-tubes due to metal part scaling down constituted an important subject within the conducted fundamental research work. Experimental results are presented, concerning the analysis of the formability of micro-tubes made from stainless steel AISI 304 with an outer diameter of 800 μm and a wall thickness of 40 μm. An average ratio of tube wall thickness to grain size of 1.54 of up to 2.56 was analyzed. Miniaturised mechanical standard methods as well as bulge tests with internal hydrostatic pressurization of the tubular specimens were applied to analyze the influence of size-dependent effects. A test device was developed for the bulge experiments which enabled the pressurization of micro-tubes with internal pressures up to 4000 bar. To determine the attainable maximum achievable expansion ratio the tubes were pressurized in the bulge tests with increasing internal pressure until instability due to necking and subsequent bursting occurred. Comparisons with corresponding tests of macro-tubes, made from the here investigated material, showed a change in formability of micro-tubes which was attributed to the scaling down of the hydroforming process. In addition, a restricted applicability of existing theoretical correlations for the determination of the maximum pressure at bursting was observed for down-scaled micro-hydroforming.

  19. Accidental Decannulation OF TRACHEOSTOMY TUBES - Case Series

    OpenAIRE

    Omokanye, HK; Dunmade, AD; Segun-Busari, S; Afolabi, OA; Habeeb, OG; Adegboye, MB; Alabi, BS

    2016-01-01

    Tracheostomy tube (TT) is usually removed in a planned manner once the patient ceases to have the condition that necessitated the procedure. Accidental decannulation or extubation refers to inadvertent removal of tracheostomy tube out of the stoma. It could prove fatal in an otherwise stable patient. We review a variety of unexpected and often-overlooked causes of accidental decannulation with suggestions on preventive measures. We therefore present three cases of accidental decannulation of ...

  20. Resolution of lava tubes with ground penetrating radar: preliminary results from the TubeX project

    Science.gov (United States)

    Esmaeili, S.; Kruse, S.; Garry, W. B.; Whelley, P.; Young, K.; Jazayeri, S.; Bell, E.; Paylor, R.

    2017-12-01

    As early as the mid 1970's it was postulated that planetary tubes or caves on other planetary bodies (i.e., the Moon or Mars) could provide safe havens for human crews, protect life and shield equipment from harmful radiation, rapidly fluctuating surface temperatures, and even meteorite impacts. What is not clear, however, are the exploration methods necessary to evaluate a potential tube-rich environment to locate suitable tubes suitable for human habitation. We seek to address this knowledge gap using a suite of instruments to detect and document tubes in a terrestrial analog study at Lava Beds National Monument, California, USA. Here we describe the results of ground penetrating radar (GPR) profiles and light detection and ranging (LiDAR) scans. Surveys were conducted from the surface and within four lava tubes (Hercules Leg, Skull, Valentine and, Indian Well Caves) with varying flow composition, shape, and complexity. Results are shown across segments of these tubes where the tubes are 10 m in height and the ceilings are 1 - 10 m below the surface. The GPR profiles over the tubes are, as expected, complex, due to scattering from fractures in roof material and three-dimensional heterogeneities. Point clouds derived from the LiDAR scans of both the interior and exterior of the lava tubes provide precise positioning of the tube geometry and depth of the ceiling and floor with respect to the surface topography. GPR profiles over LiDAR-mapped tube cross-sections are presented and compared against synthetic models of radar response to the measured geometry. This comparison will help to better understand the origins of characteristic features in the radar profiles. We seek to identify the optimal data processing and migration approaches to aid lava tube exploration of planetary surfaces.

  1. Development and Technology Transfer of the Syncro Blue Tube (Gabriel) Magnetically Guided Feeding Tube

    Science.gov (United States)

    2017-06-01

    2007; 31(4):269-73. Marderstein EL, Simmons RL, Ochoa JB. Patient safety: effect of institutional protocols on adverse events related to feeding tube...JM, Akkermans LM. Gastrointestinal motility and gastric tube feeding in mechanically ventilated patients. Crit Care Med. 1998;26:1510–1517. 4. Hsu...21 4 I. Introduction Year one of this project focused on demonstrating the effectiveness of the Syncro-BlueTube magnetically guided

  2. Forisome performance in artificial sieve tubes.

    Science.gov (United States)

    Knoblauch, Michael; Stubenrauch, Mike; van Bel, Aart J E; Peters, Winfried S

    2012-08-01

    In the legume phloem, sieve element occlusion (SEO) proteins assemble into Ca(2+)-dependent contractile bodies. These forisomes presumably control phloem transport by forming reversible sieve tube plugs. This function, however, has never been directly demonstrated, and appears questionable as forisomes were reported to be too small to plug sieve tubes, and failed to block flow efficiently in artificial microchannels. Moreover, plugs of SEO-related proteins in Arabidopsis sieve tubes do not affect phloem translocation. We improved existing procedures for forisome isolation and storage, and found that the degree of Ca(2+)-driven deformation that is possible in forisomes of Vicia faba, the standard object of earlier research, has been underestimated substantially. Forisomes deform particularly strongly under reducing conditions and high sugar concentrations, as typically found in sieve tubes. In contrast to our previous inference, Ca(2+)-inducible forisome swelling certainly seems sufficient to plug sieve tubes. This conclusion was supported by 3D-reconstructions of forisome plugs in Canavalia gladiata. For a direct test, we built microfluidics chips with artificial sieve tubes. Using fluorescent dyes to visualize flow, we demonstrated the complete blockage of these biomimetic microtubes by Ca(2+)-induced forisome plugs, and concluded by analogy that forisomes are capable of regulating phloem flow in vivo. © 2012 Blackwell Publishing Ltd.

  3. Investigations on high-pressure ribbed tubes

    Energy Technology Data Exchange (ETDEWEB)

    Kling, G.

    1942-05-01

    During hydrogenation of coal, the reactants (coal paste and hydrogen) had to be heated to reaction temperature partly by heat exchange with products and partly by heating in hairpin tubes of a preheater. These hairpin tubes were heated externally by hot circulating gases. In order to improve heat transfer from the gases to the tubes, various types of metal ribbing were welded to the tubes to catch more heat and transfer it to the tubes. This report detailed some studies on the best shapes and dimensions and numbers of plates to be used. The report was limited to flat, rectangular-cross-section plates attached perpendicularly, instead of including flat circular plates, spiral plates, or other configurations. The advantage of greater surface area to catch more heat had to be balanced off against the disadvantage of greater surface area to absorb more heat in internal resistance to heat flow. The report described the experimental conditions, the modifications tested, and the shape decided upon as best for flat plates. Some of the diagrams illustrating temperature distributions around the tubes and ribs were presented in imitation three-dimenional formats. 16 figures.

  4. Double layers - theory and experiment

    International Nuclear Information System (INIS)

    Torven, S.

    1980-06-01

    A survey is given of recent investigations of electric double layers in low density plasmas. The existence of double layers is now well established in both magnetized and unmagnetized plasmas. Laboratory experiments and numerical simulations show that double layers coexist with waves and fluctuations as expected in view of the particle beams which are formed in the layer. Under certain conditions the level of the fluctuations is small and experimental results then compare favourably with stationary double layer models. Significant progress on layer formation processes has been made, but further investigations are required to predict under what conditions double layers will form in different types of plasmas. (author)

  5. Antiviral activity of double-stranded RNA-binding protein PACT against influenza A virus mediated via suppression of viral RNA polymerase.

    Science.gov (United States)

    Chan, Chi-Ping; Yuen, Chun-Kit; Cheung, Pak-Hin Hinson; Fung, Sin-Yee; Lui, Pak-Yin; Chen, Honglin; Kok, Kin-Hang; Jin, Dong-Yan

    2018-03-07

    PACT is a double-stranded RNA-binding protein that has been implicated in host-influenza A virus (IAV) interaction. PACT facilitates the action of RIG-I in the activation of the type I IFN response, which is suppressed by the viral nonstructural protein NS1. PACT is also known to interact with the IAV RNA polymerase subunit PA. Exactly how PACT exerts its antiviral activity during IAV infection remains to be elucidated. In the current study, we demonstrated the interplay between PACT and IAV polymerase. Induction of IFN-β by the IAV RNP complex was most robust when both RIG-I and PACT were expressed. PACT-dependent activation of IFN-β production was suppressed by the IAV polymerase subunits, polymerase acidic protein, polymerase basic protein 1 (PB1), and PB2. PACT associated with PA, PB1, and PB2. Compromising PACT in IAV-infected A549 cells resulted in the augmentation of viral RNA (vRNA) transcription and replication and IFN-β production. Furthermore, vRNA replication was boosted by knockdown of PACT in both A549 cells and IFN-deficient Vero cells. Thus, the antiviral activity of PACT is mediated primarily via its interaction with and inhibition of IAV polymerase. Taken together, our findings reveal a new facet of the host-IAV interaction in which the interplay between PACT and IAV polymerase affects the outcome of viral infection and antiviral response.-Chan, C.-P., Yuen, C.-K., Cheung, P.-H. H., Fung, S.-Y., Lui, P.-Y., Chen, H., Kok, K.-H., Jin, D.-Y. Antiviral activity of double-stranded RNA-binding protein PACT against influenza A virus mediated via suppression of viral RNA polymerase.

  6. Ac-induced disruption of the doubleDs structure in tomato

    NARCIS (Netherlands)

    Rommens, Caius M.T.; Biezen, Erik A. van der; Ouwerkerk, Pieter B.F.; Nijkamp, H. John J.; Hille, Jacques

    1991-01-01

    The maize doubleDs element is stably maintained in the tomato genome. Upon the subsequent introduction of Ac into a plant containing doubleDs, disruption of the doubleDs structure and DNA rearrangements at the site of the doubleDs element were observed. No indications were obtained for excision of

  7. Advanced Ultrasupercritical (AUSC) Tube Membrane Panel Development

    Energy Technology Data Exchange (ETDEWEB)

    Pschirer, James [Alstom Power Inc., Windsor, CT (United States); Burgess, Joshua [Alstom Power Inc., Windsor, CT (United States); Schrecengost, Robert [Alstom Power Inc., Windsor, CT (United States)

    2017-08-16

    Alstom Power Inc., a wholly owned subsidiary of the General Electric Company (GE), has completed the project “Advanced Ultrasupercritical (AUSC) Tube Membrane Panel Development” under U.S. Department of Energy (DOE) Award Number DE-FE0024076. This project was part of DOE’s Novel Crosscutting Research and Development to Support Advanced Energy Systems program. AUSC Tube Membrane Panel Development was a two and one half year project to develop and verify the manufacturability and serviceability of welded tube membrane panels made from high performance materials suitable for the AUSC steam cycles, defined as high pressure steam turbine inlet conditions of 700-760°C (1292-1400°F) and 24.5-35MPa (3500-5000psi). The difficulty of this challenge lies in the fact that the membrane-welded construction imposes demands on the materials that are unlike any that exist in other parts of the boiler. Tube membrane panels have been designed, fabricated, and installed in boilers for over 50 years with relatively favorable experience when fabricated from carbon and Cr-Mo low alloy steels. The AUSC steam cycle requires membrane tube panels fabricated from materials that have not been used in a weldment with metal temperatures in the range of 582-610°C (1080-1130°F). Fabrication materials chosen for the tubing were Grade 92 and HR6W. Grade 92 is a creep strength enhanced ferritic Cr-Mo alloy and HR6W is a high nickel alloy. Once the materials were chosen, GE performed the engineering design of the panels, prepared shop manufacturing drawings, and developed manufacturing and inspection plans. After the materials were purchased, GE manufactured and inspected the tube membrane panels, determined if post fabrication heat treatment of the tube membrane panels was needed, performed pre- and post-weld heat treatment on the Grade 92 panels, conducted final nondestructive inspection of any heat treated tube membrane panels, conducted destructive inspection of the completed tube

  8. 46 CFR 153.979 - Gauging with a sounding tube.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Gauging with a sounding tube. 153.979 Section 153.979... Procedures § 153.979 Gauging with a sounding tube. (a) No person may remove the cover of a sounding tube... cargo transfer may not authorize removal of the cover from a sounding tube gauge unless all tank...

  9. Eddy current measurement of remote tube positions in CANDU reactors

    International Nuclear Information System (INIS)

    Craig, S.T.; Krause, T.W.; Luloff, B.V.; Schankula, J.J.

    2004-01-01

    Regular NDE inspections of CANDU reactors are made by inserting probes into one of 380 pressure tubes that traverse the core. Each pressure tube is surrounded by a gas annulus and contained in a calandria tube. Separation between the pressure tube and calandria tubes is maintained by four spacers. Moderator water surrounds the calandria tubes. Auxiliary tubular assemblies within the moderator run perpendicular to the pressure tube for the injection of neutron poison and for mounting flux detectors. Laboratory tests have demonstrated the use of remote field eddy currents to measure the distance between the pressure tube and auxiliary tubes. Implementation uses coils from two appropriately separated probes in existing inspection heads. These coils are the transmit coil used for sensing the spacers and the receive coil from a probe used to measure the gap between the pressure tube and its surrounding calandria tube. The axis of the transmit coil is aligned with the axis of the pressure tube. The receive coil axis is perpendicular to the transmit coil, and located near the inner diameter of the pressure tube. Although the coil spacing and orientation are not ideal, laboratory tests have demonstrated repeatable measurements under conditions of varying liftoff, pressure tube wall thickness and diameter, and gap between pressure tube and calandria tube. The experimental conditions, test cases, and results are presented. (author)

  10. 21 CFR 870.4390 - Cardiopulmonary bypass pump tubing.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiopulmonary bypass pump tubing. 870.4390... bypass pump tubing. (a) Identification. A cardiopulmonary bypass pump tubing is polymeric tubing which is used in the blood pump head and which is cyclically compressed by the pump to cause the blood to flow...

  11. Process for installing tubes in a steam generator

    International Nuclear Information System (INIS)

    Boula, G.; George, A.

    1988-01-01

    This process consists essentially to introduce the tubes by planar layers, to place antivibration bars above the layer and tensioning the bars with forces perpendicular to the layer, to check the play between the bars and the tubes and to replace the tubes beyond tolerance by other tubes [fr

  12. The Double Star mission

    Directory of Open Access Journals (Sweden)

    Liu

    2005-11-01

    Full Text Available The Double Star Programme (DSP was first proposed by China in March, 1997 at the Fragrant Hill Workshop on Space Science, Beijing, organized by the Chinese Academy of Science. It is the first mission in collaboration between China and ESA. The mission is made of two spacecraft to investigate the magnetospheric global processes and their response to the interplanetary disturbances in conjunction with the Cluster mission. The first spacecraft, TC-1 (Tan Ce means "Explorer", was launched on 29 December 2003, and the second one, TC-2, on 25 July 2004 on board two Chinese Long March 2C rockets. TC-1 was injected in an equatorial orbit of 570x79000 km altitude with a 28° inclination and TC-2 in a polar orbit of 560x38000 km altitude. The orbits have been designed to complement the Cluster mission by maximizing the time when both Cluster and Double Star are in the same scientific regions. The two missions allow simultaneous observations of the Earth magnetosphere from six points in space. To facilitate the comparison of data, half of the Double Star payload is made of spare or duplicates of the Cluster instruments; the other half is made of Chinese instruments. The science operations are coordinated by the Chinese DSP Scientific Operations Centre (DSOC in Beijing and the European Payload Operations Service (EPOS at RAL, UK. The spacecraft and ground segment operations are performed by the DSP Operations and Management Centre (DOMC and DSOC in China, using three ground station, in Beijing, Shanghai and Villafranca.

  13. Double your money

    International Nuclear Information System (INIS)

    Moxon, Suzanne

    1998-01-01

    The government-owned Hydro-Quebec was instructed to take certain actions, one of which was to increase profits. The company has published a report describing its plans for 1998-2002. The company expects to increase sales and double its income over the five years. Hydro-Quebec (which produces or purchases 97% of the electricity consumed in the province) will freeze prices until April 2002. Environmental considerations and liaison with local communities are included in the 5-year plan. The company expects to invest c$1.2B in international markets over the five years and C$20M per year are earmarked for research. (UK)

  14. Fireside carburization of stainless steel furnace tubes

    Energy Technology Data Exchange (ETDEWEB)

    Mirabal, E.; Molina, C. [PDVSA-Refineria Isla, Curayao (Netherlands); Mayorga, A.; Hau, J.L. [PDVSA-Intevep, Caracas (Venezuela)

    1999-11-01

    Most heavy Venezuelan crudes are recognized for having a high total acid number (TAN) that is usually associated with a high tendency to produce naphthenic acid corrosion. To resist this type of corrosion in vacuum heaters, 9Cr-1Mo steel and stainless steels containing molybdenum are usually recommended. In 1993 the original 5Cr-1/2Mo roof tubes of the furnace in a vacuum unit were replaced by stainless steel 316Ti to minimize tube replacement and increase heater reliability. Unexpectedly, some of the new tubes failed after only three years of service, and just one year after undergoing the last turnaround inspection. The damage occurred in the form of deep holes and perforations, starting from the outside tube surface on the fireside. Coke build-up occurred due to severe operating conditions, overheating the tubes on the fireside, above 675 C (1250 F). Metallographic and Scanning Electron Microscopic (SEM) examination revealed internal and external carburization of the material due to the presence of coke and combustion ashes, respectively. The increase in the skin metal temperature facilitated the diffusion of carbon from these carbon-rich deposits into the low carbon content material (0.023 O/O).Depletion of chromium at the grain boundaries due to the massive formation of chromium carbides, resulted in a severe intergranular corrosion attack by molten salts rich in vanadium and sulfur due to asphalt burning. Normal operating practice demands the use of steam for the heater tubes to control coke build-up. This practice had been first reduced and then eliminated, during the past two years prior to the failure, because of economic incentives. This paper describes the root cause analysis conducted to account for these premature tube failures.

  15. Compounded Apixaban Suspensions for Enteral Feeding Tubes.

    Science.gov (United States)

    Caraballo, Maria L; Donmez, Seda; Nathan, Kobi; Zhao, Fang

    2017-07-01

    Objective: There is limited information on compounded apixaban formulations for administration via enteral feeding tubes. This study was designed to identify a suitable apixaban suspension formulation that is easy to prepare in a pharmacy setting, is compatible with commonly used feeding tubes, and has a beyond-use date of 7 days. Methods: Apixaban suspensions were prepared from commercially available 5-mg Eliquis tablets. Several vehicles and compounding methods were screened for ease of preparation, dosage accuracy, and tube compatibility. Two tubing types, polyurethane and polyvinyl chloride, with varying lengths and diameters, were included in the study. They were mounted on a peg board during evaluation to mimic the patient body position. A 7-day stability study of the selected formulation was also conducted. Results: Vehicles containing 40% to 60% Ora-Plus in water all exhibited satisfactory flowability through the tubes. The mortar/pestle compounding method was found to produce more accurate and consistent apixaban suspensions than the pill crusher or crushing syringe method. The selected formulation, 0.25 mg/mL apixaban in 50:50 Ora-Plus:water, was compatible with both tubing types, retaining >98% drug in posttube samples. The stability study also confirmed that this formulation was stable physically and chemically over 7 days of storage at room temperature. Conclusions: A suitable apixaban suspension formulation was identified for administration via enteral feeding tubes. The formulation consisted of 0.25 mg/mL apixaban in 50:50 Ora-Plus:water. The stability study results supported a beyond-use date of 7 days at room temperature.

  16. Flat Tile Armour Cooled by Hypervapotron Tube: a Possible Technology for ITER

    Science.gov (United States)

    Schlosser, J.; Escourbiac, F.; Merola, M.; Schedler, B.; Bayetti, P.; Missirlian, M.; Mitteau, R.; Robin-Vastra, I.

    Carbon fibre composite (CFC) flat tile armours for actively cooled plasma facing components (PFC’s) are an important challenge for controlled fusion machines. Flat tile concepts, water cooled by tubes, were studied, developed, tested and finally operated with success in Tore Supra. The components were designed for 10 MW/m2 and mock-ups were successfully fatigue tested at 15 MW/m2, 1000 cycles. For ITER, a tube-in-tile concept was developed and mock-ups sustained up to 25 MW/m2 for 1000 cycles without failure. Recently flat tile armoured mock-ups cooled by a hypervapotron tube successfully sustained a cascade failure test under a mean heat flux of 10 MW/m2 but with a doubling of the heat flux on some tiles to simulate missing tiles (500 cycles). This encouraging results lead to reconsider the limits for flat tile concept when cooled by hypervapotron (HV) tube. New tests are now scheduled to investigate these limits in regard to the ITER requirements. Experimental evidence of the concept could be gained in Tore Supra by installing a new limiter into the machine.

  17. Impurities incorporation into magnetite scale formed on simulated steam generator tubing

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, K.; Yamaguchi, K.; Koike, M. [Kyushu Electric Power Co., Inc. (Japan); Kawamura, H.; Hirano, H. [Central Research Inst. of Electric Power Industry (Japan); Yamada, Y.; Nakamura, T. [The Kansai Electric Power Co., Inc. (Japan)

    2002-07-01

    From a viewpoint of ensuring the integrity of steam generators (SGs) tubing in PWR plants, the research was made into how impurities in the secondary coolant are incorporated into magnetite (Fe{sub 3}O{sub 4}) scale formed on the tube in a laboratory test. We experimented with a method to form Fe{sub 3}O{sub 4} scale on a tube under a boiling heat transfer condition in the laboratory test, simulating the conditions of SG in the actual PWR plants. Based on the scale formation method, we investigated the incorporation of sulfur (S) into the scale. S is known as the most common impurity solved in the secondary coolant and a dominant factor in making heat transfer crevice environment acidic. The effects of sodium (Na) and silicon (Si), solved in test solution with S, on the S incorporation into scale were also investigated. The test resulted in a double-layered scale being formed on the tube surface, with the outer scale being porous and the inner scale dense. It was revealed that the S incorporation into scales was affected by the S concentration in the solution and existence of other impurities, such as Na and Si. (authors)

  18. Impurities incorporation into magnetite scale formed on simulated steam generator tubing

    International Nuclear Information System (INIS)

    Takahashi, K.; Yamaguchi, K.; Koike, M.; Kawamura, H.; Hirano, H.; Yamada, Y.; Nakamura, T.

    2002-01-01

    From a viewpoint of ensuring the integrity of steam generators (SGs) tubing in PWR plants, the research was made into how impurities in the secondary coolant are incorporated into magnetite (Fe 3 O 4 ) scale formed on the tube in a laboratory test. We experimented with a method to form Fe 3 O 4 scale on a tube under a boiling heat transfer condition in the laboratory test, simulating the conditions of SG in the actual PWR plants. Based on the scale formation method, we investigated the incorporation of sulfur (S) into the scale. S is known as the most common impurity solved in the secondary coolant and a dominant factor in making heat transfer crevice environment acidic. The effects of sodium (Na) and silicon (Si), solved in test solution with S, on the S incorporation into scale were also investigated. The test resulted in a double-layered scale being formed on the tube surface, with the outer scale being porous and the inner scale dense. It was revealed that the S incorporation into scales was affected by the S concentration in the solution and existence of other impurities, such as Na and Si. (authors)

  19. Flat Tile Armour Cooled by Hypervapotron Tube: a Possible Technology for ITER

    International Nuclear Information System (INIS)

    Schlosser, J.; Escourbiac, F.; Bayetti, P.; Missirlian, M.; Mitteau, R.; Merola, M.; Schedler, B.; Bobin-Vastra, I.

    2004-01-01

    Carbon fibre composite (CFC) flat tile armours for actively cooled plasma facing components (PFC's) are an important challenge for controlled fusion machines. Flat tile concepts, water cooled by tubes, were studied, developed, tested and finally operated with success in Tore Supra. The components were designed for 10MW/m 2 and mock-ups were successfully fatigue tested at 15MW/m 2 ; 1000 cycles. For ITER, a tube-in-tile concept was developed and mock-ups sustained up to 25MW/m 2 for 1000 cycles without failure. Recently flat tile armoured mock-ups cooled by a hypervapotron tube successfully sustained a cascade failure test under a mean heat flux of 10MW/m 2 but with a doubling of the heat flux on some tiles to simulate missing tiles (500 cycles). This encouraging results lead to reconsider the limits for flat tile concept when cooled by hypervapotron (HV) tube. New tests are now scheduled to investigate these limits in regard to the ITER requirements. Experimental evidence of the concept could be gained in Tore Supra by installing a new limiter into the machine

  20. Flat tile armour cooled by hypervapotron tube: a possible technology for ITER

    International Nuclear Information System (INIS)

    Schlosser, J.; Escourbiac, F.; Bayetti, P.; Missirlian, M.; Mitteau, R.; Schedler, B.; Bobin-Vastra, I.

    2003-01-01

    Carbon fibre composite (CFC) flat tile armours for actively cooled plasma facing components (PFC's) are an important challenge for controlled fusion machine. Flat tile concepts, water cooled by tubes, were studied, developed, tested and finally experienced with success in Tore Supra. The components were designed for 10 MW/m 2 and mock-ups were successfully fatigue tested at 15 MW/m 2 , 1000 cycles. For ITER, a tube-in-tile concept was developed and mock-ups sustained up to 25 MW/m 2 for 1000 cycles without failure. Recently flat tile armored mock-ups cooled by Hypervapotron tube successfully sustained a cascade failure test under a mean heat flux of 10 MW/m 2 but with a doubling of the heat flux on some tiles to simulate missing tiles (500 cycles). This encouraging results lead to reconsider the limits for flat tile concept when cooled by Hypervapotron tube. New tests are now scheduled to investigate these limits notably in regards to the ITER requirements. The concept could also be experimented in Tore Supra by installing a new limiter into the machine. (authors)

  1. Synchronized and concurrent experiments in Moving Tube NMR: using separate sample volumes for different pulse sequences.

    Science.gov (United States)

    Donovan, Kevin J

    2014-10-01

    This study presents a new application of sample shuttling with a long NMR tube (Moving Tube NMR, MT-NMR) as a method for collecting different experiments synchronously or even concurrently using separate sample regions. Synchronized experiments were performed using an automated shuttling apparatus to move different sample regions into the coil between transients such that each experiment was collected using a separate, specific sample segment. Additionally, a 2D NOESY spectrum and a double quantum filtered COSY (DQCOSY) spectrum were collected concurrently by shuttling between two different sample regions during the NOESY mixing time. These applications of the Moving Tube technique show that it is a useful platform for compounded data acquisition to optimize spectrometer time by minimizing measurement times and avoiding problems arising from instrument and sample instabilities. Furthermore, collecting a DQCOSY during a 2D NOESY mixing time opens a wide array of possibilities, as this principle can be applied to collect any experiment during a NOESY mixing time provided that the mixing period is longer than the sum of the sample shuttling time plus a complete scan of the intermittent experiment. While this methodology relies on the use of a long sample tube, it does not require excessive sample volumes, as two milliliters is enough to constitute multiple sample regions. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Nasogastric tube insertion using airway tube exchanger in anesthetized and intubated patients.

    Science.gov (United States)

    Kim, Hyae-Jin; Lee, Hyeon Jeong; Cho, Hyun-Jun; Kim, Hae-Kyu; Cho, Ah-Reum; Oh, Narae

    2016-12-01

    A nasogastric tube (NGT) is commonly inserted into patients undergoing abdominal surgery to decompress the stomach during or after surgery. However, for anatomic reasons, the insertion of NGTs into anesthetized and intubated patients may be challenging. We hypothesized that the use of a tube exchanger for NGT insertion could increase the success rate and reduce complications. One hundred adult patients, aged 20-70 years, who were scheduled for gastrointestinal surgeries with general anesthesia and NGT insertion were enrolled in our study. The patients were randomly allocated to the tube-exchanger group or the control group. The number of attempts, the time required for successful NGT insertion, and the complications were noted for each patient. In the tube-exchanger group, the success rate of NGT insertion on the first attempt was 92%, which is significantly higher than 68%, the rate in the control group (P = 0.007). The time required for successful NGT insertion in the tube-exchanger group was 18.5 ± 8.2 seconds, which is significantly shorter than the control group, 75.1 ± 9.8 seconds (P tube-exchanger group. There were many advantages in using a tube-exchanger as a guide to inserting NGTs in anesthetized and intubated patients. Compared to the conventional technique, the use of a tube-exchanger resulted in a higher the success rate of insertion on the first attempt, a shorter procedure time, and fewer complications.

  3. Vibro-impact responses of a tube with tube--baffle interaction

    International Nuclear Information System (INIS)

    Shin, Y.S.; Sass, D.E.; Jendrzejczyk, J.A.

    1978-01-01

    The relatively small, inherent tube-to-baffle hole clearances associated with manufacturing tolerances in heat exchangers affect the vibrational characteristics and the response of the tube. Numerical studies were made to predict the vibro-impact response of a tube with tube-baffle interaction. The finite element method has been employed with a non-linear elastic contact spring-dashpot to model the effect of the relative approach between the tube and the baffle plate. The coupled equations of motion are directly integrated with a proportional system damping represented by a linear combination of mass and stiffness. Lumped mass approach with explicit time integration scheme was found to be a suitable choice for tube-baffle impacting analysis. Fourier analyses indicate that the higher mode contributions to the tube response are significant for strong tube-baffle impacting. The contact damping forces are negligible compared with the contact spring forces. The numerical analysis results are in reasonably good agreement with those of the experiments

  4. Fluid heating by current injection tubes; Chauffage de fluides par tubes a passage de courant

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, L.S. [Societe Parmilleux (France)

    1999-04-01

    Current injection tube technology may be applied in compact fluid heating installation with a very low level of thermal inertia. The technology is particularly suitable for heating heat-sensitive fluids or those with a tendency to foul other types of installations. Specific advantages of current injection tubes include the elimination of cold spots and their reduced volume requirements. (author)

  5. Inpatient tube weaning in children with long-term feeding tube dependency: A retrospective analysis.

    Science.gov (United States)

    Trabi, Thomas; Dunitz-Scheer, Marguerite; Kratky, Elisabeth; Beckenbach, Hannes; Scheer, Peter J

    2010-11-01

    This study investigates the outcome of an intervention program to establish oral feeding after prolonged tube feeding in children. The intervention is based on supervised reduction of enteral formula within a few days supported by a 3-week program of speech therapy, occupational therapy, psychoanalytically based eating therapy, physical therapy, psychodynamic coaching, and nutritional counseling of the infant and his or her parents. Two hundred twenty-one cases were included in this study. All patients had been severely ill or were handicapped and had been exclusively fed by tube for most of their lives. The major outcome variable was complete discontinuation of tube feeding with sufficient oral feeding after treatment, defined as the child's ability to sustain stable body weight by self-motivated oral feeding. Two hundred three patients (92%) were completely fed orally after treatment. Tube feeding was discontinued completely within 8 days in mean, and mean in-patient treatment time was 21.6 days. The current method can be used by a trained and experienced team to wean tube-dependent children from prolonged tube feeding. Tube weaning should be addressed from the beginning of tube feeding in all children who are expected to restore oral feeding after the phase of nutritional stabilization. Since successful programs are rare, we were motivated to present our results of this elaborate program in this article. Copyright © 2010 Michigan Association for Infant Mental Health.

  6. Residual stresses estimation in tubes after rapid heating of surface

    International Nuclear Information System (INIS)

    Serikov, S.V.

    1992-01-01

    Results are presented on estimation of residual stresses in tubes of steel types ShKh15, EhP836 and 12KIMF after heating by burning pyrotechnic substance inside tubes. External tube surface was heated up to 400-450 deg C under such treatment. Axial stresses distribution over tube wall thickness was determined for initial state, after routine heat treatment and after heating with the use of fireworks. Inner surface heating was shown to essentially decrease axial stresses in tubes

  7. Automated Diagnosis and Classification of Steam Generator Tube Defects

    International Nuclear Information System (INIS)

    Garcia, Gabe V.

    2004-01-01

    A major cause of failure in nuclear steam generators is tube degradation. Tube defects are divided into seven categories, one of which is intergranular attack/stress corrosion cracking (IGA/SCC). Defects of this type usually begin on the outer surface of the tubes and propagate both inward and laterally. In many cases these defects occur at or near the tube support plates. Several different methods exist for the nondestructive evaluation of nuclear steam generator tubes for defect characterization

  8. SHEATHED TUBE AND APPARATUS AND METHOD OF PRODUCTION THEREOF

    Science.gov (United States)

    Ohlinger, L.A.

    1959-08-18

    A tubular fuel element covered inside and out by a unitary covering tube originally about twice its length and of small enough diameter to fit snugly inside the fuel tube is described. The covering tube is then reentrantly folded back by a pressure-die mechanism over both ends of the fuel tube and againsts outside until the folded back ends of the covering tube meet where they are welded in a single seam running circumferentially around the middle of the resulting assembly.

  9. CFD Studies on Multi Lead Rifled [MLR] Boiler Tubes

    OpenAIRE

    Dr T C Mohankumar

    2013-01-01

    This paper reports the merits of multi lead rifled [MLR] tubes in vertical water tube boiler using CFD tool. Heat transfer enhancement of MLR tubes was mainly taken in to consideration. Performance of multi lead rifled tube was studied by varying its influencing geometrical parameter like number of rifling, height of rifling, length of pitch of rifling for a particular length. The heat transfer analysis was done at operating conditions of an actual coal fired water tube boiler situated at Apo...

  10. Automated Diagnosis and Classification of Steam Generator Tube Defects

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Gabe V. Garcia

    2004-10-01

    A major cause of failure in nuclear steam generators is tube degradation. Tube defects are divided into seven categories, one of which is intergranular attack/stress corrosion cracking (IGA/SCC). Defects of this type usually begin on the outer surface of the tubes and propagate both inward and laterally. In many cases these defects occur at or near the tube support plates. Several different methods exist for the nondestructive evaluation of nuclear steam generator tubes for defect characterization.

  11. Kennedy Space Center Fixation Tube (KFT)

    Science.gov (United States)

    Richards, Stephanie E.; Levine, Howard G.; Romero, Vergel

    2016-01-01

    Experiments performed on the International Space Station (ISS) frequently require the experimental organisms to be preserved until they can be returned to earth for analysis in the appropriate laboratory facility. The Kennedy Fixation Tube (KFT) was developed to allow astronauts to apply fixative, chemical compounds that are often toxic, to biological samples without the use of a glovebox while maintaining three levels of containment (Fig. 1). KFTs have been used over 200 times on-orbit with no leaks of chemical fixative. The KFT is composed of the following elements: a polycarbonate main tube where the fixative is loaded preflight, the sample tube where the plant or other biological specimens is placed during operations, the expansion plug, actuator, and base plug that provides fixative containment (Fig. 2). The main tube is pre-filled with 25 mL of fixative solution prior to flight. When actuated, the specimen contained within the sample tube is immersed with approximately 22 mL (+/- 2 mL) of the fixative solution. The KFT has been demonstrated to maintain its containment at ambient temperatures, 4degC refrigeration and -100 C freezing conditions.

  12. Calandria cooling structure in pressure tube reactor

    International Nuclear Information System (INIS)

    Hyugaji, Takenori; Sasada, Yasuhiro.

    1976-01-01

    Purpose: To contrive the structure of a heavy water distributing device in a pressure tube reactor thereby to reduce the variation in the cooling function thereof due to the welding deformation and installation error. Constitution: A heating water distributing plate is provided at the lower part of the upper tubular plate of a calandria tank to form a heavy water distributing chamber between both plates and a plurality of calandria tubes. Heavy water which has flowed in the upper part of the heavy water distributing plate from the heavy water inlet nozzle flows down through gaps formed around the calandria tubes, whereby the cooling of the calandria tank and the calandria tubes is carried out. In the above described calandria cooling structure, a heavy water distributing plate support is provided to secure the heavy water distributing plate and torus-shaped heavy water distributing rings are fixed to holes formed in the heavy water distributing plate penetrating through the calandria tubes thereby to form torus-shaped heavy water outlet ports each having a space. (Seki, T.)

  13. Solitary wave propagation in solar flux tubes

    International Nuclear Information System (INIS)

    Erdelyi, Robert; Fedun, Viktor

    2006-01-01

    The aim of the present work is to investigate the excitation, time-dependent dynamic evolution, and interaction of nonlinear propagating (i.e., solitary) waves on vertical cylindrical magnetic flux tubes in compressible solar atmospheric plasma. The axisymmetric flux tube has a field strength of 1000 G at its footpoint, which is typical for photospheric regions. Nonlinear waves that develop into solitary waves are excited by a footpoint driver. The propagation of the nonlinear signal is investigated by solving numerically a set of fully nonlinear 2.0D magnetohydrodynamic (MHD) equations in cylindrical coordinates. For the initial conditions, axisymmetric solutions of the linear dispersion relation for wave modes in a magnetic flux tube are applied. In the present case, we focus on the sausage mode only. The dispersion relation is solved numerically for a range of plasma parameters. The equilibrium state is perturbed by a Gaussian at the flux tube footpoint. Two solitary solutions are found by solving the full nonlinear MHD equations. First, the nonlinear wave propagation with external sound speed is investigated. Next, the solitary wave propagating close to the tube speed, also found in the numerical solution, is studied. In contrast to previous analytical and numerical works, here no approximations were made to find the solitary solutions. A natural application of the present study may be spicule formation in the low chromosphere. Future possible improvements in modeling and the relevance of the photospheric chromospheric transition region coupling by spicules is suggested

  14. Air liquide's space pulse tube cryocooler systems

    Science.gov (United States)

    Trollier, T.; Tanchon, J.; Buquet, J.; Ravex, A.

    2017-11-01

    Thanks to important development efforts completed with ESA funding, Air Liquide Advanced Technology Division (AL/DTA), is now in position to propose two Pulse Tube cooler systems in the 40-80K temperature range for coming Earth Observation missions such as Meteosat Third Generation (MTG), SIFTI, etc… The Miniature Pulse Tube Cooler (MPTC) is lifting up to 2.47W@80K with 50W compressor input power and 10°C rejection temperature. The weight is 2.8 kg. The Large Pulse Tube Cooler (LPTC) is providing 2.3W@50K for 160W input power and 10°C rejection temperature. This product is weighing 5.1 kg. The two pulse tube coolers thermo-mechanical units are qualified against environmental constraints as per ECSS-E-30. They are both using dual opposed pistons flexure bearing compressor with moving magnet linear motors in order to ensure very high lifetime. The associated Cooler Drive Electronics is also an important aspect specifically regarding the active control of the cooler thermo-mechanical unit during the launch phase and the active reduction of the vibrations induced by the compressor (partly supported by the French Agency CNES). This paper details the presentation of the two Pulse Tube Coolers together with the Cooler Drive Electronics aspects.

  15. Electroacoustic control of Rijke tube instability

    Science.gov (United States)

    Zhang, Yumin; Huang, Lixi

    2017-11-01

    Unsteady heat release coupled with pressure fluctuation triggers the thermoacoustic instability which may damage a combustion chamber severely. This study demonstrates an electroacoustic control approach of suppressing the thermoacoustic instability in a Rijke tube by altering the wall boundary condition. An electrically shunted loudspeaker driver device is connected as a side-branch to the main tube via a small aperture. Tests in an impedance tube show that this device has sound absorption coefficient up to 40% under normal incidence from 100 Hz to 400 Hz, namely over two octaves. Experimental result demonstrates that such a broadband acoustic performance can effectively eliminate the Rijke-tube instability from 94 Hz to 378 Hz (when the tube length varies from 1.8 m to 0.9 m, the first mode frequency for the former is 94 Hz and the second mode frequency for the latter is 378 Hz). Theoretical investigation reveals that the devices act as a damper draining out sound energy through a tiny hole to eliminate the instability. Finally, it is also estimated based on the experimental data that small amount of sound energy is actually absorbed when the system undergoes a transition from the unstable to stable state if the contrpaol is activated. When the system is actually stabilized, no sound is radiated so no sound energy needs to be absorbed by the control device.

  16. Some features of plastic streamer tube operation

    International Nuclear Information System (INIS)

    Guz, Yu.P.; Lapin, V.V.; Obraztsov, V.F.; Zaitsev, A.M.

    1986-01-01

    In the framework of the construction of the DELPHI hadron calorimeter the properties of plastic streamer tubes with high resistivity cathodes and external pick-up electrodes have been investigated. The tube structure consists of an extruded PVC profile (PVC+10% CaCO 3 ), shaped as an open 8-cell element where 80 μ anode wires are stretched along. All the wires are soldered to the HV connector via damping resistors. A PVC cover is placed on the top of it to close the 8-tube element with the inner cross section 9x9 mm. Both the top cover and open profile are coated with graphite paint on the side facing the wires, acting as the resistive cathode of the device. The 8-tube element is inside an extruded PVC container. External pick-up electrodes (pads) are used to detect induced pulses, transmitted through the resistive cathode. Most of the tests were made with 1 m long tubes and normally with a gas mixture composed of Ar:C 4 H 10 =1:3. A possible method of improving their operation performances with the help of an additional ''antistatic'' cover is demonstrated

  17. Finite-size effect on the Raman-active modes of double-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Sbai, K [Equipe de Physique Informatique et Modelisation des Systemes, Universite MY Ismail, Faculte des Sciences, BP 11201, Zitoune, 50000 Meknes (Morocco); Rahmani, A [Equipe de Physique Informatique et Modelisation des Systemes, Universite MY Ismail, Faculte des Sciences, BP 11201, Zitoune, 50000 Meknes (Morocco); Chadli, H [Equipe de Physique Informatique et Modelisation des Systemes, Universite MY Ismail, Faculte des Sciences, BP 11201, Zitoune, 50000 Meknes (Morocco); Sauvajol, J-L [Laboratoire des Colloides, Verres et Nanomateriaux (UMR CNRS 5587), Universite Montpellier II, 34095 Montpellier Cedex 5 (France)

    2008-01-09

    The dependence of the breathing-like phonon modes (BLM) and tangential-like phonon modes (TLM) of individual, finite and infinite bundles of double-walled carbon nanotubes (DWCNTs) as a function of the relative lengths of the inner (L{sub i}) and outer (L{sub o}) tubes is calculated by using the spectral moments method in the framework of the bond-polarization theory. Depending on the relative lengths of the inner (L{sub i}) and outer (L{sub o}) tubes, additional modes are evidenced in the BLM region. These modes must be considered in the analysis of the experimental data.

  18. Improvement of heat transfer by means of ultrasound: Application to a double-tube heat exchanger.

    Science.gov (United States)

    Legay, M; Simony, B; Boldo, P; Gondrexon, N; Le Person, S; Bontemps, A

    2012-11-01

    A new kind of ultrasonically-assisted heat exchanger has been designed, built and studied. It can be seen as a vibrating heat exchanger. A comprehensive description of the overall experimental set-up is provided, i.e. of the test rig and the acquisition system. Data acquisition and processing are explained step-by-step with a detailed example of graph obtained and how, from these experimental data, energy balance is calculated on the heat exchanger. It is demonstrated that ultrasound can be used efficiently as a heat transfer enhancement technique, even in such complex systems as heat exchangers. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Precursors to New Molecular Tube Ligands. 1. Double-Capped Trinuclear Cobalt Complexes of Aminoethanethiol.

    Science.gov (United States)

    Arnold, Alan P.; Bhula, Rajumati; Chen, Xiangna; Geue, Rodney J.; Jackson, W. Gregory

    1999-05-03

    Co(SCH(2)CH(2)NH(2))(3) has been capped on the facial amines through protection of the thiolates by coordination of two such complexes to a central Co(III) ion. The trinuclear species forming the framework is the complex ion [Co{Co(SCH(2)CH(2)NH(2))(3)}(2)](3+), 1, in meso and rac forms which have been chromatographically separated and identified. Hexaimine derivatives of 1, [Co{Co(SCH(2)CH(2)N=CH(2))(3)}(2)](3+), 2, have been synthesized in good yield by reaction with excess paraformaldehyde and base in CH(3)CN. The hexaimines have been reacted with NH(3) to yield dicapped aza species [Co{Co(SCH(2)CH(2)NHCH(2))(3)N}(2)](3+), 3, or reacted with nitromethane to yield the nitro-capped ions [Co{Co(SCH(2)CH(2)NHCH(2)C)(3)CNO(2)}(2)](3+), 4. The reactions are retentive; i.e., meso reactant yields meso product. All of the products have been characterized by (1)H NMR, (13)C NMR, and UV-vis spectroscopy. Electrochemical measurements (CV and dc coulometry) in CH(3)CN indicate that the central Co(III) ion in all of the species is reduced first, followed by the two terminal Co(III) centers. The formal potentials show that the Co(III) oxidation state is stabilized by the six thiolate bridging ligands in comparison to six thioether donor atoms, whereas capping has a destabilizing effect.

  20. Detailed Root Cause Analysis of SG Tube ODSCC Indications within the Tube Sheets of NPP Biblis Unit A

    Science.gov (United States)

    Kilian, R.; Beck, J.; Lang, H.; Schönherr, T.; Widera, M.

    Biblis Unit A is a Siemens/KWU type four loop PWR equipped with SG tubing made from Stainless Steel Alloy 800, operating from 1975 until the shutdown in 2011 due to the German political decision of a quick nuclear phase out. During the regular SG tubing inspections using eddy current testing in 2005 and 2006, a few SG tube indications were detected within the tube sheet between upper and lower mechanical tube expansion. These indications were limited to the outer tube bundle periphery. As a consequence two tubes with EC indications were pulled in 2006 for further investigations. The destructive examinations revealed axially oriented cracks starting from the outer tube surface (ODSCC). The analysis of the debris from the upper expansion area clearly indicated the presence of secondary side water in the volume between tube sheet and SG tube. Penetration of secondary side water is only possible by a penetration path along the upper expansion.

  1. Development of a 39.5 GHz Karp traveling wave tube for use in space

    Science.gov (United States)

    Jacquez, A.; Wilson, D.

    1988-10-01

    A millimeter-wave TWT was developed using a dispersive, high-impedance forward wave interaction structure based on a ladder, with non-space-harmonic interaction, for a tube with high gain per inch and high efficiency. The 'Tunneladder' interaction structure combines ladder properties modified to accommodate Pierce gun beam optics on a radially magnetized PM focusing structure. The development involved the fabrication of chemically milled, shaped ladders diffusion brazed to each ridge of a double ridged waveguide. Cold-test data are presented, representing the omega-Beta and impedance characteristics of the modified ladder circuit These results were used in small and large-signal computer programs to predict TWT gain and efficiency. A laboratory model tube was designed and fabricated, including all major subassemblies.

  2. Performance study of a fin and tube heat exchanger with different fin geometry

    DEFF Research Database (Denmark)

    Singh, Shobhana; Sørensen, Kim; Condra, Thomas Joseph

    2016-01-01

    This study analyses the effect of different fin geometries on the heat transfer and pressure loss characteristics of a fin and tube heat exchanger. A numerical investigation is carried out on liquid–gas type double-finned tube heat exchanger under cross-flow condition. Three different cross......-sections namely: a) Rectangular, b) Trapezoidal, c) Triangular are adopted to define the fin geometry. The CFD simulations are performed to incorporate coupled steady state conjugate heat transfer with the turbulent flow phenomenon for the Reynolds number in the range of 5000-13000. Dimensionless heat transfer...... models show that triangular fin geometry can provide higher heat transfer performance in comparison to the fins with rectangular and trapezoidal geometry with lower pressure loss and a bonus of 7.27% reduction in weight under similar operating conditions....

  3. High efficiency 40 K single-stage Stirling-type pulse tube cryocooler

    Science.gov (United States)

    Wu, X. L.; Chen, L. B.; Pan, C. Z.; Cui, C.; Wang, J. J.; Zhou, Y.

    2017-12-01

    A high efficiency single-stage Stirling-type coaxial pulse tube cryocooler (SPTC) operating at around 40 K has been designed, built and tested. The double-inlet and the inertance tubes together with the gas reservoir were adopted as the phase shifters. Under the conditions of 2.5 MPa charging pressure and 30 Hz operating frequency, the prototype has achieved a no-load temperature of 23.8 K with 330 W of electric input power at a rejection temperature of 279 K. When the input power increases to 400 W, it can achieve a cooling capacity of 4.7 W/40 K while rejecting heat at 279 K yielding an efficiency of 7.02% relative to Carnot. It achieves a cooling capacity of 5 W/40 K with an input power of 450 W. It takes 10 minutes for the SPTC to cool to its no-load temperature of 40 K from 295 K.

  4. Steam generator tube denting simulation testing

    International Nuclear Information System (INIS)

    Battaglia, P.J.; Singley, W.J.

    1978-02-01

    Tube denting has been reported in steam generators in a number of commercial nuclear power plants in recent years. In order to aid in understanding of the mechanism leading to tube denting in the steam generators, a Bettis laboratory test program was initiated to attempt to reproduce tube denting and to investigate the effects of chemistry, design, and temperature. The results of the tests indicate that denting can be reproduced in the small model steam generator test apparatus devised for this testing. Denting was observed under carbon steel support plates in seawater-contaminated secondary water in a test with hydrazine-ammonia chemistry and a primary water inlet temperature of 590 0 F and in a test with hydrazine-morpholine chemistry and a primary water inlet temperature of 545 0 F. The parameters of these two tests simulate conditions in a typical commercial steam generator and the Shippingport Atomic Power Station steam generators, respectively

  5. Fluid structure interaction in tube bundles

    International Nuclear Information System (INIS)

    Brochard, D.; Jedrzejewski, F.; Gibert, R.J.

    1995-01-01

    A lot of industrial components contain tube bundles immersed in a fluid. The mechanical analysis of such systems requires the study of the fluid structure interaction in the tube bundle. Simplified methods, based on homogenization methods, have been developed to analyse such phenomenon and have been validated through experimental results. Generally, these methods consider only the fluid motion in a plan normal to the bundle axis. This paper will analyse, in a first part, the fluid structure interaction in a tube bundle through a 2D finite element model representing the bundle cross section. The influence of various parameters like the bundle size, and the bundle confinement will be studied. These results will be then compared with results from homogenization methods. Finally, the influence of the 3D fluid motion will be investigated, in using simplified methods. (authors). 11 refs., 12 figs., 2 tabs

  6. Advanced tube-bundle rocket thrust chamber

    Science.gov (United States)

    Kazaroff, John M.; Pavli, Albert J.

    1990-01-01

    An advanced rocket thrust chamber for future space application is described along with an improved method of fabrication. Potential benefits of the concept are improved cyclic life, reusability, and performance. Performance improvements are anticipated because of the enhanced heat transfer into the coolant which will enable higher chamber pressure in expander cycle engines. Cyclic life, reusability and reliability improvements are anticipated because of the enhanced structural compliance inherent in the construction. The method of construction involves the forming of the combustion chamber with a tube-bundle of high conductivity copper or copper alloy tubes, and the bonding of these tubes by an electroforming operation. Further, the method of fabrication reduces chamber complexity by incorporating manifolds, jackets, and structural stiffeners while having the potential for thrust chamber cost and weight reduction.

  7. Circumferential cracking of steam generator tubes

    International Nuclear Information System (INIS)

    Karwoski, K.J.

    1997-04-01

    On April 28, 1995, the U.S. Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 95-03, open-quote Circumferential Cracking of Steam Generator Tubes.close-quote GL 95-03 was issued to obtain information needed to verify licensee compliance with existing regulatory requirements regarding the integrity of steam generator tubes in domestic pressurized-water reactors (PWRs). This report briefly describes the design and function of domestic steam generators and summarizes the staff's assessment of the responses to GL 95-03. The report concludes with several observations related to steam generator operating experience. This report is intended to be representative of significant operating experience pertaining to circumferential cracking of steam generator tubes from April 1995 through December 1996. Operating experience prior to April 1995 is discussed throughout the report, as necessary, for completeness

  8. New discharge tube with virtual cathode

    International Nuclear Information System (INIS)

    Seidelmann, L.; Aubrecht, L.

    2003-01-01

    Till this time known methods of the excitation of the discharge between electrodes are using either secondary or thermo emission of electrons by the cathode. Usually we speak about the self-maintained discharge. Lifetime of the cathode, that is shortened by the emission, limits in principle, the lifetime of the whole discharge tube. The discharge can, according to the present state of the art, be induced also by the inductive way. Arrangement for excitation of such discharge is rather expensive. The construction of the inductive excited discharge tube is considerably influenced by the necessity of the limitation of the losses in excitation magnetic circuits. Especially length of the discharge and pressure of the working gas are limited by the economic standpoints. Function of the discharge is always connected with unwanted electromagnetic radiation, whose restraint is expensive and represents limiting factor for arrangement of the discharge tube (Authors)

  9. A miniature high repetition rate shock tube

    Science.gov (United States)

    Tranter, R. S.; Lynch, P. T.

    2013-09-01

    A miniature high repetition rate shock tube with excellent reproducibility has been constructed to facilitate high temperature, high pressure, gas phase experiments at facilities such as synchrotron light sources where space is limited and many experiments need to be averaged to obtain adequate signal levels. The shock tube is designed to generate reaction conditions of T > 600 K, P < 100 bars at a cycle rate of up to 4 Hz. The design of the apparatus is discussed in detail, and data are presented to demonstrate that well-formed shock waves with predictable characteristics are created, repeatably. Two synchrotron-based experiments using this apparatus are also briefly described here, demonstrating the potential of the shock tube for research at synchrotron light sources.

  10. Non-uniform tube representation of proteins

    DEFF Research Database (Denmark)

    Hansen, Mikael Sonne

    Treating the full protein structure is often neither computationally nor physically possible. Instead one is forced to consider various reduced models capturing the properties of interest. Previous work have used tubular neighborhoods of the C-alpha backbone. However, assigning a unique radius...... might not correctly capture volume exclusion - of crucial importance when trying to understand a proteins $3$d-structure. We propose a new reduced model treating the protein as a non-uniform tube with a radius reflecting the positions of atoms. The tube representation is well suited considering X......-ray crystallographic resolution ~ 3Å while a varying radius accounts for the different sizes of side chains. Such a non-uniform tube better capture the protein geometry and has numerous applications in structural/computational biology from the classification of protein structures to sequence-structure prediction....

  11. Direct ophthalmoscopy on YouTube

    DEFF Research Database (Denmark)

    Borgersen, Nanna Jo; Henriksen, Mikael Johannes Vuokko; Konge, Lars

    2016-01-01

    BACKGROUND: Direct ophthalmoscopy is well-suited for video-based instruction, particularly if the videos enable the student to see what the examiner sees when performing direct ophthalmoscopy. We evaluated the pedagogical effectiveness of instructional YouTube videos on direct ophthalmoscopy...... in general. We then systematically searched YouTube. Two authors reviewed eligible videos to assess eligibility and extract data on video statistics, content, and approach to visualization. Correlations between video statistics and contents were investigated using two-tailed Spearman's correlation. RESULTS...... the patient and how to examine the fundus. Time spent on fundus examination correlated with the number of views per week (Spearman's ρ=0.53; P=0.029). CONCLUSION: Videos may help overcome the pedagogical issues in teaching direct ophthalmoscopy; however, the few available videos on YouTube fail to address...

  12. Expressly Fabricated Molar Tube Bases: Enhanced Adhesion

    Science.gov (United States)

    Phull, Tarun Singh; Rana, Tarun; Kumar, Varun

    2014-01-01

    Clinicians, Orthodontists and their patients’ parents often expect the best results in the shortest time span possible. Orthodontic bonding of molar tubes has been an acceptable risk in a modern era of refined biomaterials and instrumentation. Although many orthodontists still prefer banding to bonding, it is the failure rate of the tubes on molars which accounts to an impedance in molar bonding. One of the reasons for molar attachment failures is attributed to improper adaptation of the buccal tube base with or without increased thickness of composite. Merits of banding the second molars especially when these are the terminal teeth for anchorage have been overemphasized in the literature. The present article presents a simple and relatively less time consuming technique of preparing molar tubes to be bonded on tooth surfaces which may be quite difficult to isolate especially for bonding, for example, mandibular second molars. The increased surface area of the composite scaffold helps not only in enhanced bond strength but also serves to reduce the incidence of plaque accumulation given the dexterity of invitro preparation. The removal of the occlusal part of the molar tube scaffold helps in prevention of open / raised bite tendencies. The present innovation, therefore, is not merely serendipity but a structured technique to overcome a common dilemma for the clinical orthodontist. The present dictum of banding being superior to molar tube bonding may prove to be futile with trendsetting molar attachments. It is also an established fact that bonding proves to be a lesser expensive modality when compared to banding procedures. PMID:25121070

  13. Performance of the hybrid photomultiplier tube (HPMT)

    Energy Technology Data Exchange (ETDEWEB)

    Schomaker, R.J. [B.V. Delft Electronische Producten, Roden (Netherlands)

    1995-12-31

    The HPMT, which may be an alternative for PhotoMultiplier Tubes (PMT`s) in many applications, is a vacuum tube in which the latest technologies of photocathodes and photodiodes are combined. Photo-electrons are accelerated and bombarding a reversely biased PIN diode, where they create many electron-hole-pairs. The resulting charge pulse can be amplified and further processed. The HPMT shows many superior characteristics compared to regular PMT`s, because it does not suffer the statistical fluctuations common for electron multiplication processes. An energy resolution of up to 14 photo-electrons will be presented, together with striking figures for dynamic range and timing behavior.

  14. Cathode Readout with Stripped Resistive Drift Tubes

    International Nuclear Information System (INIS)

    Bychkov, V.N.; Kekelidze, G.D.; Novikov, E.A.; Peshekhonov, V.D.; Shafranov, M.D.; Zhil'tsov, V.E.

    1994-01-01

    A straw tube drift chamber prototype has been constructed and tested. The straw tube material is mylar film covered with carbon layer of resistivity 0.5, 30 and 70 k Ohm/sq. The gas mixture used was Ar/CH 4 . Both the anode wire and cathode signals were detected in order to study the behaviour of the chamber in the presence of X-ray ionization. The construction and the results of the study are presented. 7 refs., 11 figs., 1 tab

  15. Beware of the malformed nasogastric tube

    Science.gov (United States)

    Garg, Rakesh; Khanna, Puneet; S, Siva Kumaran; Sonny, Abraham

    2009-01-01

    Untoward events with faulty instruments and apparatus are well known and if not recognised can be disastrous. We present a case of a faulty nasogastric tube having both ends sharp-edged and closed with a detachable blocker. In our case, had we inserted the faulty nasogastric tube, the impact of the blocker, although small, in the tract could have eroded the nasal/oesophageal/gastric mucosa causing its sequalae. Thus, we would like to emphasise the need to check all instruments before using them to prevent any catastrophic complication. PMID:21686494

  16. Observation of a Coulomb flux tube

    Science.gov (United States)

    Greensite, Jeff; Chung, Kristian

    2018-03-01

    In Coulomb gauge there is a longitudinal color electric field associated with a static quark-antiquark pair. We have measured the spatial distribution of this field, and find that it falls off exponentially with transverse distance from a line joining the two quarks. In other words there is a Coulomb flux tube, with a width that is somewhat smaller than that of the minimal energy flux tube associated with the asymptotic string tension. A confinement criterion for gauge theories with matter fields is also proposed.

  17. Detection of ''beading faults'' in welded tubes

    International Nuclear Information System (INIS)

    Mondot, J.

    In the steel tube industry the word ''beading'' refers to a highly localised leak affecting the welded zone. During the pneumatic test its flow rate is generally very low no more than a few thousandths of a mm 3 /second. Detection of such a fault by this test is consequently slow, and those which are choked or at the limit of leakage may escape detection. For greater safety, the tube technician is now using non-destructive testing methods such as eddy-currents and ultrasonics [fr

  18. Pulse tube coolers for Meteosat third generation

    International Nuclear Information System (INIS)

    Butterworth, James; Aigouy, Gérald; Chassaing, Clement; Debray, Benoît; Huguet, Alexandre

    2014-01-01

    Air Liquide's Large Pulse Tube Coolers (LPTC) will be used to cool the focal planes of the Infrared Sounder (IRS) and Flexible Combined Imager (FCI) instruments aboard the ESA/Eumetsat satellites Meteosat Third Generation (MTG). This cooler consists of an opposed piston linear compressor driving a pulse tube cold head and the associated drive electronics including temperature regulation and vibration cancellation algorithms. Preparations for flight qualification of the cooler are now underway. In this paper we present results of the optimization and qualification activities as well as an update on endurance testing

  19. Nitrous oxide use and endotracheal tube rupture.

    Science.gov (United States)

    Mosby, E L; Schelkun, P M; Vincent, S K

    1988-01-01

    Nitrous oxide is an important and widely used anesthetic agent. However, during lengthy surgical procedures, significant amounts of nitrous oxide diffuse into the endotracheal tube cuff, causing sequelae that may include increased cuff pressures, tracheal trauma, increased postoperative discomfort, and cuff rupture. In this paper, two cases are presented in which the endotracheal tube cuff used to deliver this anesthetic agent ruptured after more than four hours of surgery. Two simple means of limiting the diffusion of nitrous oxide into the cuff and thus preventing this occurrence are described.

  20. Digital Radiography Qualification of Tube Welding

    Science.gov (United States)

    Carl, Chad

    2012-01-01

    The Orion Project will be directing Lockheed Martin to perform orbital arc welding on commodities metallic tubing as part of the Multi Purpose Crew Vehicle assembly and integration process in the Operations and Checkout High bay at Kennedy Space Center. The current method of nondestructive evaluation is utilizing traditional film based x-rays. Due to the high number of welds that are necessary to join the commodities tubing (approx 470), a more efficient and expeditious method of nondestructive evaluation is desired. Digital radiography will be qualified as part of a broader NNWG project scope.

  1. Self-assembling segmented coiled tubing

    Science.gov (United States)

    Raymond, David W.

    2016-09-27

    Self-assembling segmented coiled tubing is a concept that allows the strength of thick-wall rigid pipe, and the flexibility of thin-wall tubing, to be realized in a single design. The primary use is for a drillstring tubular, but it has potential for other applications requiring transmission of mechanical loads (forces and torques) through an initially coiled tubular. The concept uses a spring-loaded spherical `ball-and-socket` type joint to interconnect two or more short, rigid segments of pipe. Use of an optional snap ring allows the joint to be permanently made, in a `self-assembling` manner.

  2. Double profunda brachii artery

    Directory of Open Access Journals (Sweden)

    Gavishiddappa A Hadimani

    2016-01-01

    Full Text Available Brachial artery (BA is a continuation of the axillary artery at the lower border of teres major. In the cubital fossa, BA divides into radial artery and ulnar artery as terminal branches. Large branch given from the BA in the upper part is profunda brachii artery. In the present case, we noticed double profunda brachii that arises from the BA. They are profunda brachii artery 1 and profunda brachii artery 2. Profunda brachii artery 1 arises in the proximal part of the BA and profunda brachii artery 2 arises distal to the profunda brachii artery 1. Both the arteries run inferolaterally in the spiral groove along with radial nerve. Variations of profunda brachii artery are important during harvesting of the lateral arm flaps and may lead to inadvertent injury during percutaneous arterial catheterization or injection of drugs.

  3. Double-Skin Facade

    DEFF Research Database (Denmark)

    Kalyanova, Olena

    , transparent insulation and preheating operation modes of DSF cavity. The data sets include measurements of naturally induced air flow, temperature gradients, velocity profiles, climate data, etc. Two data sets were used for further empirical validation of building simulation software for DSF modelling within...... favored by companies and their employees. To bring the reduction of energy use in these buildings application of suitable tools and methods is necessary to achieve successful design solutions. Earlier work on the topic of DSF modelling was examined from various publications. As a result, the main...... to perform the simulations. To fill in the gap of lacking experimental data a range of measurements was carried out in an outdoor, double-skin façade full-scale test facility ‘The Cube'. As a result, three complete sets of experimental data were composed. These are available for external air curtain...

  4. GENERALIZED DOUBLE PARETO SHRINKAGE.

    Science.gov (United States)

    Armagan, Artin; Dunson, David B; Lee, Jaeyong

    2013-01-01

    We propose a generalized double Pareto prior for Bayesian shrinkage estimation and inferences in linear models. The prior can be obtained via a scale mixture of Laplace or normal distributions, forming a bridge between the Laplace and Normal-Jeffreys' priors. While it has a spike at zero like the Laplace density, it also has a Student's t -like tail behavior. Bayesian computation is straightforward via a simple Gibbs sampling algorithm. We investigate the properties of the maximum a posteriori estimator, as sparse estimation plays an important role in many problems, reveal connections with some well-established regularization procedures, and show some asymptotic results. The performance of the prior is tested through simulations and an application.

  5. Doubled Color Codes

    Science.gov (United States)

    Bravyi, Sergey

    Combining protection from noise and computational universality is one of the biggest challenges in the fault-tolerant quantum computing. Topological stabilizer codes such as the 2D surface code can tolerate a high level of noise but implementing logical gates, especially non-Clifford ones, requires a prohibitively large overhead due to the need of state distillation. In this talk I will describe a new family of 2D quantum error correcting codes that enable a transversal implementation of all logical gates required for the universal quantum computing. Transversal logical gates (TLG) are encoded operations that can be realized by applying some single-qubit rotation to each physical qubit. TLG are highly desirable since they introduce no overhead and do not spread errors. It has been known before that a quantum code can have only a finite number of TLGs which rules out computational universality. Our scheme circumvents this no-go result by combining TLGs of two different quantum codes using the gauge-fixing method pioneered by Paetznick and Reichardt. The first code, closely related to the 2D color code, enables a transversal implementation of all single-qubit Clifford gates such as the Hadamard gate and the π / 2 phase shift. The second code that we call a doubled color code provides a transversal T-gate, where T is the π / 4 phase shift. The Clifford+T gate set is known to be computationally universal. The two codes can be laid out on the honeycomb lattice with two qubits per site such that the code conversion requires parity measurements for six-qubit Pauli operators supported on faces of the lattice. I will also describe numerical simulations of logical Clifford+T circuits encoded by the distance-3 doubled color code. Based on a joint work with Andrew Cross.

  6. Disinfection of Biofilms in Tubes with Ultraviolet Light

    DEFF Research Database (Denmark)

    Bak, Jimmy; Begovic, Tanja

    2009-01-01

    Bacterial biofilms on long-term catheters are a major source of infection. We demonstrate here the potential of UVC light emitting diodes (LED) for disinfection purposes in catheter like tubes contaminated with biofilm. We show that UVC Light propagation is possible through teflon tubes using...... that the UVC light attenuation inside the tube can be described by an exponential function depending of tube length and various loss mechanisms. The disinfection efficiency of the UVC diodes is demonstrated on tubes contaminated artificially with a Pseudomonas aeruginosa biofilm. The tubes were connected...... to a flow system and biofilms were produced during a three day period. Tubes in lengths of 10 cm (FEP teflon) were contaminated. Tubes for control and for UVC treatment were contaminated in parallel. The control and UVC treated tubes were both filled with a 20 % NaCl solution during the UVC treatment time...

  7. Heat conduction in double-walled carbon nanotubes with intertube additional carbon atoms.

    Science.gov (United States)

    Cui, Liu; Feng, Yanhui; Tan, Peng; Zhang, Xinxin

    2015-07-07

    Heat conduction of double-walled carbon nanotubes (DWCNTs) with intertube additional carbon atoms was investigated for the first time using a molecular dynamics method. By analyzing the phonon vibrational density of states (VDOS), we revealed that the intertube additional atoms weak the heat conduction along the tube axis. Moreover, the phonon participation ratio (PR) demonstrates that the heat transfer in DWCNTs is dominated by low frequency modes. The added atoms cause the mode weight factor (MWF) of the outer tube to decrease and that of the inner tube to increase, which implies a lower thermal conductivity. The effects of temperature, tube length, and the number and distribution of added atoms were studied. Furthermore, an orthogonal array testing strategy was designed to identify the most important structural factor. It is indicated that the tendencies of thermal conductivity of DWCNTs with added atoms change with temperature and length are similar to bare ones. In addition, thermal conductivity decreases with the increasing number of added atoms, more evidently for atom addition concentrated at some cross-sections rather than uniform addition along the tube length. Simultaneously, the number of added atoms at each cross-section has a considerably more remarkable impact, compared to the tube length and the density of chosen cross-sections to add atoms.

  8. Formation of Double Neutron Stars, Millisecond Pulsars and Double ...

    Indian Academy of Sciences (India)

    Edward P. J. Heuvel

    2017-09-12

    Sep 12, 2017 ... Abstract. The 1982 model for the formation of Hulse–Taylor binary radio pulsar PSR B1913+16 is described, which since has become the 'standard model' for the formation of the double neutron stars, confirmed by the. 2003 discovery of the double pulsar system PSR J0737-3039AB. A brief overview is ...

  9. Draping Double-Layer Woven Fabrics Onto Double-Curvature ...

    African Journals Online (AJOL)

    Draping woven fabrics to complex parts with double curvature leads to complex redistribution and reorientation of the yarns in composites reinforced with woven preforms. To reduce the risk of fabric tearing or wrinkling we propose to use double-layer woven fabrics. This paper presents a simulation model for draping

  10. Everything the nurse practitioner should know about pediatric feeding tubes.

    Science.gov (United States)

    Hannah, Erin; John, Rita Marie

    2013-11-01

    To provide an overview of the current feeding tubes in use in the pediatric population including feeding tube complications, and specific guidance for patients at the initiation, throughout the use of, and at the discontinuation of tube feeding. A review of the literature was performed using multiple databases including PubMed, CINAHL, Ovid Medline, and Cochrane Library. Key words used included pediatric gastrostomy (G) tubes, nasogastric (NG) tubes, gastrojejunostomy (GJ) tubes, enteral access, and nurse practitioner (NP). Any child who cannot obtain nutrition orally is a candidate for enteral feeding tube access. Tube feeding is the recommended care guideline for children that are undernourished or unable to safely take-in oral nutrition. Tube feeding has been known to improve health-related quality of life. There are a number of different forms of feeding tubes that can be used in children, including NG, orogastric, G, and GJ tubes. Children are being sent home regularly with enteral feeding tube access and NPs will encounter these patients in everyday practice. It is important that NPs know the risks and benefits of tube feeding as well as the types of tubes currently in use and their indications, advantages, disadvantages, and complications. ©2013 The Author(s) ©2013 American Association of Nurse Practitioners.

  11. Manipulation and functionalization of nano-tubes: application to boron nitride nano-tubes

    International Nuclear Information System (INIS)

    Maguer, A.

    2007-01-01

    This PhD work is divided into two parts dealing with boron nitride (BNNT) and carbon nano-tubes. The first part is about synthesis, purification and chemical functionalization of BNNT. Single-walled BNNT are synthesized by LASER ablation of a hBN target. Improving the synthesis parameters first allowed us to limit the byproducts (hBN, boric acid). A specific purification process was then developed in order to enrich the samples in nano-tubes. Purified samples were then used to develop two new chemical functionalization methods. They both involve chemical molecules that present a high affinity towards the BN network. The use of long chain-substituted quinuclidines and borazines actually allowed the solubilization of BNNT in organic media. Purification and functionalization were developed for single-walled BNNT and were successfully applied to multi-walled BNNT. Sensibility of boron to thermic neutrons finally gave birth to a study about covalent functionalization possibilities of the network. The second part of the PhD work deals with separation of carbon nano-tubes depending on their properties. Microwave irradiation of carbon nano-tubes first allowed the enrichment of initially polydisperse samples in large diameter nano-tubes. A second strategy involving selective interaction between one type of tubes and fullerene micelles was finally envisaged to selectively solubilize carbon nano-tubes with specific electronic properties. (author) [fr

  12. Influence of tube spinning on formability of friction stir welded aluminum alloy tubes for hydroforming application

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.S. [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Hu, Z.L., E-mail: zhilihuhit@163.com [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Hubei Key Laboratory of Advanced Technology of Automobile Parts, Wuhan University of Technology, Wuhan 430070 (China); State Key Laboratory of Materials Processing and Die and Mould Technology, Huazhong University of Science and Technology (China); Yuan, S.J. [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Hua, L. [Hubei Key Laboratory of Advanced Technology of Automobile Parts, Wuhan University of Technology, Wuhan 430070 (China)

    2014-06-01

    Due to economic and ecological reasons, the application of tailor-welded blanks of aluminum alloy has gained more and more attention in manufacturing lightweight structures for automotives and aircrafts. In the study, the research was aimed to highlight the influence of spinning on the formability of FSW tubes. The microstructural characteristics of the FSW tubes during spinning were studied by electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM). The formability of the FSW tubes with different spinning reduction was assessed by hydraulic bulge test. It is found that the spinning process shows a grain refinement of the tube. The grains of the FSW tube decrease with increasing thickness reduction, and the effect of grain refinement is more obvious for the BM compared to that of the weld. The difference of grain size and precipitates between the weld and BM leads to an asymmetric W-type microhardness distribution after spinning. The higher thickness reduction of the tube, the more uniform distribution of grains and precipitates it shows, and consequently results in more significant increase of strength. As compared with the result of tensile test, the tube after spinning shows better formability when the stress state changes from uniaxial to biaxial stress state.

  13. Microscopical investigation of steamside oxide on X20CrMoV121 superheater tubes

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Hansson, Anette Nørgaard; Jensen, Søren A.

    2011-01-01

    X20CrMoV121 is a 12%Cr martensitic steel which has been used in power plants in Europe for many decades. Superheater tubes exposed for various durations up to 135,000 hours in power plants in Denmark at steam temperatures varying from 450 to 575°C were investigated. Light optical and scanning ele...... electron microscopy was used to investigate steamside oxide morphologies. At all temperatures there is a double layered oxide, however, the inner:outer oxide thickness is not always equal. At the lower steam temperature range of...

  14. Performance of pressure tubes in CANDU reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, D.; Griffiths, M.; Bickel, G.; Buyers, A.; Coleman, C.; Nordin, H.; St Lawrence, S. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

    2016-06-15

    The pressure tubes in CANDU reactors typically operate for times up to about 30 years prior to refurbishment. The in-reactor performance of Zr-2.5Nb pressure tubes has been evaluated by sampling and periodic inspection. This paper describes the behavior and discusses the factors controlling the behaviour of these components. The Zr–2.5Nb pressure tubes are nominally extruded at 815{sup o}C, cold worked nominally 27%, and stress relieved at 400 {sup o}C for 24 hours, resulting in a structure consisting of elongated grains of hexagonal close-packed alpha-Zr, partially surrounded by a thin network of filaments of body-centred-cubic beta-Zr. These beta-Zr filaments are meta-stable and contain about 20% Nb after extrusion. The stress-relief treatment results in partial decomposition of the beta-Zr filaments with the formation of hexagonal close-packed alpha-phase particles that are low in Nb, surrounded by a Nb-enriched beta-Zr matrix. The material properties of pressure tubes are determined by variations in alpha-phase texture, alpha-phase grain structure, network dislocation density, beta-phase decomposition, and impurity concentration that are a function of manufacturing variables. The pressure tubes operate at temperatures between 250 {sup o}C and 310 {sup o}C with coolant pressures up to about 11 MPa in fast neutron fluxes up to 4 x 10{sup 17} n·m{sup -2}·s{sup -1} (E > 1 MeV) and the properties are modified by these conditions. The properties of the pressure tubes in an operating reactor are therefore a function of both manufacturing and operating condition variables. The ultimate tensile strength, fracture toughness, and delayed hydride-cracking properties (velocity (V) and threshold stress intensity factor (K{sub IH})) change with irradiation, but all reach a nearly limiting value at a fluence of less than 10{sup 25} n·m{sup -2} (E > 1 MeV). At this point the ultimate tensile strength is raised about 200 MPa, toughness is reduced by about 50%, V increases

  15. Doubled haploid production from Spanish onion (Allium cepa L. germplasm: embryogenesis induction, plant regeneration and chromosome doubling

    Directory of Open Access Journals (Sweden)

    Oreto eFayos

    2015-05-01

    Full Text Available The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2 to 3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09% and Fuentes de Ebro the lowest (0.53%. These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%, whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%. Different amiprofos-methyl (APM treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 µM APM in liquid medium. However, the application of 25 µM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the 4 regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their

  16. YouTube as an information source for pediatric adenotonsillectomy and ear tube surgery.

    Science.gov (United States)

    Sorensen, Jeffrey A; Pusz, Max D; Brietzke, Scott E

    2014-01-01

    Assess the overall quality of information on adenotonsillectomy and ear tube surgery presented on YouTube (www.youtube.com) from the perspective of a parent or patient searching for information on surgery. The YouTube website was systematically searched on select dates with a formal search strategy to identify videos pertaining to pediatric adenotonsillectomy and ear tube surgery. Only videos with at least 5 (ear tube surgery) or 10 (adenotonsillectomy) views per day were included. Each video was viewed and scored by two independent scorers. Videos were categorized by goal and scored for video/audio quality, accuracy, comprehensiveness, and procedure-specific content. Cross-sectional study. Public domain website. Fifty-five videos were scored for adenotonsillectomy and forty-seven for ear tube surgery. The most common category was educational (65.3%) followed by testimonial (28.4%), and news program (9.8%). Testimonials were more common for adenotonsillectomy than ear tube surgery (41.8% vs. 12.8%, p=0.001). Testimonials had a significantly lower mean accuracy (2.23 vs. 2.62, p=0.02), comprehensiveness (1.71 vs. 2.22, p=0.007), and TA specific content (0.64 vs. 1.69, p=0.001) score than educational type videos. Only six videos (5.9%) received high scores in both video/audio quality and accuracy/comprehensiveness of content. There was no significant association between the accuracy and comprehensive score and views, posted "likes", posted "dislikes", and likes/dislikes ratio. There was an association between "likes" and mean video quality (Spearman's rho=0.262, p=0.008). Parents/patients searching YouTube for information on pediatric adenotonsillectomy and ear tube surgery will generally encounter low quality information with testimonials being common but of significantly lower quality. Viewer perceived quality ("likes") did not correlate to formally scored content quality. Published by Elsevier Ireland Ltd.

  17. An advanced tube wear and fatigue workstation to predict flow induced vibrations of steam generator tubes

    International Nuclear Information System (INIS)

    Gay, N.; Baratte, C.; Flesch, B.

    1997-01-01

    Flow induced tube vibration damage is a major concern for designers and operators of nuclear power plant steam generators (SG). The operating flow-induced vibrational behaviour has to be estimated accurately to allow a precise evaluation of the new safety margins in order to optimize the maintenance policy. For this purpose, an industrial 'Tube Wear and Fatigue Workstation', called 'GEVIBUS Workstation' and based on an advanced methodology for predictive analysis of flow-induced vibration of tube bundles subject to cross-flow has been developed at Electricite de France. The GEVIBUS Workstation is an interactive processor linking modules as: thermalhydraulic computation, parametric finite element builder, interface between finite element model, thermalhydraulic code and vibratory response computations, refining modelling of fluid-elastic and random forces, linear and non-linear dynamic response and the coupled fluid-structure system, evaluation of tube damage due to fatigue and wear, graphical outputs. Two practical applications are also presented in the paper; the first simulation refers to an experimental set-up consisting of a straight tube bundle subject to water cross-flow, while the second one deals with an industrial configuration which has been observed in some operating steam generators i.e., top tube support plate degradation. In the first case the GEVIBUS predictions in terms of tube displacement time histories and phase planes have been found in very good agreement with experiment. In the second application the GEVIBUS computation showed that a tube with localized degradation is much more stable than a tube located in an extended degradation zone. Important conclusions are also drawn concerning maintenance. (author)

  18. Are long corolla tubes in Pedicularis driven by pollinator selection?

    Science.gov (United States)

    Huang, Shuang-Quan; Wang, Xiang-Ping; Sun, Shi-Guo

    2016-08-01

    The evolution of long corolla tubes has been hypothesized to be driven by long-tongued pollinators. Corolla tubes in Pedicularis species can be longer than 10 cm which may function as flower stalks to increase visual attractiveness to pollinators because these species provide no nectar and are pollinated by bumblebees. The corolla tube length was manipulated (shorter or longer) in two Pedicularis species in field to examine whether longer tubes are more attractive to pollinators and produce more seeds than short tubes. Our results did not support the pollinator attraction hypothesis, leaving the evolution of long tubes in Pedicularis remains mysterious. © 2015 Institute of Botany, Chinese Academy of Sciences.

  19. Damping of multispan heat exchanger tubes. Pt. 1: in gases

    International Nuclear Information System (INIS)

    Pettigrew, M.J.; Goyder, H.G.D.; Qiao, Z.L.; Axisa, F.

    1986-07-01

    Flow-induced vibration analyses of heat exchanger tubes require the knowledge of damping. This paper treats the question of damping on multispan heat exchanger tubes in air and gases. The different energy dissipation mechanisms that contribute to tube damping are discussed. The available experimental data are reviewed and analysed. We find that the main damping mechanism in gases is friction between tube and tube-supports. Damping is strongly related to tube-support thickness. Damping values are recommended for design purposes. This study is interesting in the nuclear industry for it often uses heat exchangers

  20. Maintenance of immersion ultrasonic testing on the water tube boiler

    International Nuclear Information System (INIS)

    Ishiyama, Toru; Kawasaki, Ichio; Miura, Hirohito

    2014-01-01

    There are 4-boiler in nuclear fuel cycle engineering laboratories (NCL). These boilers have been operated in the long term over 20 years. One of them, the leakage of boiler water was found at one of the generating tubes, and 2 adjoining generating tubes were corroded in Dec, 2011. These generating tubes were investigated by immersion ultrasonic testing (UT) for measure thickness of the tube. As a result, thinner tube was found in a part of a bend and near the water drum. These parts are covered with sulfide deposit, it seems that the generating tubes were corroded by sulfide. (author)