Gas Shielding Technology for Welding and Brazing

Welding is a common method that allows two metallic materials to be joined together with high structural integrity. When joints need to be leak-tight, light-weight, or free of contaminant-trapping seams or surface asperities, welding tends to be specified. There are many welding techniques, each with its own advantages and disadvantages. Some of these techniques include Forge Welding, Gas Tungsten Arc Welding, Friction Stir Welding, and Laser Beam Welding to name a few. Whichever technique is used, the objective is a structural joint that meets the requirements of a particular component or assembly. A key practice in producing quality welds is the use of shielding gas. This article discusses various weld techniques, quality of the welds, and importance of shielding gas in each of those techniques. Metallic bonds, or joints, are produced when metals are put into intimate contact. In the solid-state "blacksmith welding" process, now called Forge Welding (FOW), the site to be joined is pounded into intimate contact. The surfaces to be joined usually need to be heated to make it easier to deform the metal. The surfaces are sprinkled with a flux to melt surface oxides and given a concave shape so that surface contamination can be squeezed out of the joint as the surfaces are pounded together; otherwise the surface contamination would be trapped in the joint and would weaken the weld. In solid-state welding processes surface oxides or other contamination are typically squeezed out of the joint in "flash.

Comparing outpatient oral antibiotic use in Germany and the Netherlands from 2012 to 2016.

PURPOSE: Overuse of antibiotics is of concern, but may differ between European countries. This study compares outpatient use of oral antibiotics between Germany (DE) and the Netherlands (NL). METHODS: For DE, we used the DAPI database with information on dispensings at the expense of the Statutory Health Insurance Funds from > 80% of community pharmacies. For NL, data were obtained from the Dutch Foundation for Pharmaceutical Statistics. Use of oral antibiotics was estimated as defined daily doses per 1000 inhabitants per day (DID), except for age comparisons as packages per 1000 inhabitants annually. National time trends were assessed with linear regression, stratified for the major antibiotic classes, and individual substances. RESULTS: From 2012 to 2016, outpatient antibiotic use was lower in NL than in DE (9.64 vs 14.14 DID in 2016) and non-significantly decreased slightly over time in both countries. In DE, dispensings of oral antibiotics to children were higher compared with NL for the age groups 2 to 5 (2.0-fold in 2016) and 6 to 14 years (2.7-fold in 2016). Use of cephalosporins was very low in NL (0.02 DID in 2016), but the second most frequently dispensed class in DE (2.95 DID in 2016). CONCLUSION: From 2012 to 2016, outpatient use of oral antibiotics was lower in NL than in DE. Differences were primarily observed in the age groups 2 to 5 and 6 to 14 years, although the recommendations of evidence-based guidelines in both countries were in agreement

Quality Appraisal of Ambulatory Oral Cephalosporin and Fluoroquinolone Use in the 16 German Federal States from 2014-2019.

Background: Despite concerns about causing bacterial resistance and serious side effects, oral cephalosporins and fluoroquinolones are still frequently prescribed in Germany. We aimed to test a method for the detection of regional quality differences in the use of oral cephalosporins and fluoroquinolones and to apply this to the German federal states. Methods: Use of antibiotics from 2014–2019 was analyzed using dispensing data from community pharmacies claimed to the statutory health insurance (SHI) funds. Quality of regional antibiotic use in 2019 was assessed by calculating indicators based on defined daily doses per 1000 SHI-insured persons per day (DID). Oral cephalosporin and fluoroquinolone use was followed by linear regression analyses. Results: The method used was suitable to find meaningful quality differences in ambulatory oral cephalosporin and fluoroquinolone use between the German federal states. In 2019, DID varied from 1.62 in Brandenburg to 3.17 in Rhineland-Palatinate for cephalosporins and from 0.47 in Brandenburg to 0.89 in Saarland for fluoroquinolones. The city-states Hamburg, Bremen, and Berlin showed highest quality with the applied indicator set. From 2014–2019, a significant decrease in utilization of oral cephalosporins was found in all federal states. During 2017–2019, all states showed a significant decline of fluoroquinolone us

Change of Exposure Time Mid-Test in High Temperature DIC Measurement

Performing digital image correlation (DIC) at extreme temperatures has been greatly challenging due to the radiation which saturates the camera sensor. At such high temperatures, the light intensity emitted from an object is occasionally so powerful that the acquired images are overwhelmingly saturated. This induces data loss, potentially ruining the test, thus requiring the user to restart the test. For this reason, selection of an appropriate camera sensitivity plays a crucial role prior to beginning the test. Exposure time is a factor contributing to camera sensitivity and it is the easiest setting to manipulate during the test since it introduces minimal errors when comparing to other factors, especially in quasi-static tests. This paper examines the influence of changing exposure time mid-test on DIC measurement uncertainty. The investigation was conducted by rigid body motion experiments at room temperature and 1600 °C, respectively. Thereby, some recommendations are given to help DIC users assess their images at room temperature to extrapolate the exposure at extreme temperatures along with accompanying solutions to salvage data at high temperature

Resurrecting the F-1 - 3D Scanning to Digitally Capture the Saturn V Main Engine

No abstract availabl

Light Meson Dynamics Workshop. Mini proceedings

The mini-proceedings of the Light Meson Dynamics Workshop held in Mainz from February 10th to 12th, 2014, are presented. The web page of the conference, which contains all talks, can be found at https://indico.cern.ch/event/287442/overview .Comment: 46 pages, 17 contributions. Editors: W. Gradl, P. Masjuan, M. Ostrick, and S. Schere

Issues and Opportunities in Exotic Hadrons

The last few years have been witness to a proliferation of new results concerning heavy exotic hadrons. Experimentally, many new signals have been discovered that could be pointing towards the existence of tetraquarks, pentaquarks, and other exotic configurations of quarks and gluons. Theoretically, advances in lattice field theory techniques place us at the cusp of understanding complex coupled-channel phenomena, modelling grows more sophisticated, and effective field theories are being applied to an ever greater range of situations. It is thus an opportune time to evaluate the status of the field. In the following, a series of high priority experimental and theoretical issues concerning heavy exotic hadrons is presented.Comment: White paper from INT workshop, "Modern Exotic Hadrons". References added. Version to appear in Chinese Physics

Comparison of contrast enhanced color Doppler targeted biopsy to conventional systematic biology: Impact on Gleason score

Purpose: Prostate cancer grading with Gleason score is an important prognostic factor. This prospective randomized study compares ultrasound systematic biopsy vs contrast enhanced color Doppler targeted biopsy for the impact on Gleason score findings. Materials and Methods: We examined 690 men (mean age 56 years, range 41 to 77) with a serum total prostate specific antigen of 1.25 ng/ml or greater, a free-to-total prostate specific antigen ratio less than 18% and/or a suspicious digital rectal examination. Contrast enhanced color Doppler targeted biopsies with a limited number of cores (5 or less) were performed in hypervascular areas of the peripheral zone during administration of the ultrasound contrast agent SonovueTM(Bracco, Milano, Italy). Ten systematic biopsies were obtained in a standard spatial distribution. Cancer detection rates and Gleason score were compared. Results: Prostate cancer was identified in 221 of 690 subjects (32%) with a mean prostate specific antigen of 4.6 ng/ml (range 1.4 to 35.0). Prostate cancer was detected in 180 of 690 subjects (26%) with contrast enhanced color Doppler targeted biopsy and in 166 of 690 patients (24%) with systematic ultrasound biopsy. The Gleason score of all 180 cancers detected on contrast enhanced color Doppler targeted biopsy was 6 or higher (mean 6.8). The Gleason score of all 166 cancers detected on systematic biopsy ranged from 4 to 6 and mean Gleason score was 5.4. Contrast enhanced color Doppler targeted biopsy detected significantly higher Gleason scores compared to systematic biopsy (Wilcoxon rank sum test p \u3c0.003). Conclusions: Contrast enhanced color Doppler targeted biopsy detected cancers with higher Gleason scores and more cancer than systematic biopsy. Therefore, contrast enhanced color Doppler seems to be helpful in the grading of prostate cancer, which is important for defining prognosis and deciding treatment

Carbon-Carbon Nozzle Extension Development in Support of In-Space and Upper-Stage Liquid Rocket Engines

No abstract availabl