Review and Study of Physics Driven Pitting Corrosion Modeling in 2024-T3 Aluminum Alloys (Postprint)
2015-05-01
AFRL-RX-WP-JA-2015-0218 REVIEW AND STUDY OF PHYSICS DRIVEN PITTING CORROSION MODELING IN 2024-T3 ALUMINUM ALLOYS (POSTPRINT) Lingyu...2014 – 1 April 2015 4. TITLE AND SUBTITLE REVIEW AND STUDY OF PHYSICS DRIVEN PITTING CORROSION MODELING IN 2024-T3 ALUMINUM ALLOYS (POSTPRINT) 5a...18 Review and Study of Physics Driven Pitting Corrosion Modeling in 2024-T3 Aluminum Alloys Lingyu Yu 1*, Kumar V. Jata2 1Mechanical Engineering
Inexpensive Open-Source Data Logging in the Field
NASA Astrophysics Data System (ADS)
Wickert, A. D.
2013-12-01
I present a general-purpose open-source field-capable data logger, which provides a mechanism to develop dense networks of inexpensive environmental sensors. This data logger was developed as a low-power variant of the Arduino open-source development system, and is named the ALog ("Arduino Logger") BottleLogger (it is slim enough to fit inside a Nalgene water bottle) version 1.0. It features an integrated high-precision real-time clock, SD card slot for high-volume data storage, and integrated power switching. The ALog can interface with sensors via six analog/digital pins, two digital pins, and one digital interrupt pin that can read event-based inputs, such as those from a tipping-bucket rain gauge. We have successfully tested the ALog BottleLogger with ultrasonic rangefinders (for water stage and snow accumulation and melt), temperature sensors, tipping-bucket rain gauges, soil moisture and water potential sensors, resistance-based tools to measure frost heave, and cameras that it triggers based on events. The source code for the ALog, including functions to interface with a a range of commercially-available sensors, is provided as an Arduino C++ library with example implementations. All schematics, circuit board layouts, and source code files are open-source and freely available under GNU GPL v3.0 and Creative Commons Attribution-ShareAlike 3.0 Unported licenses. Through this work, we hope to foster a community-driven movement to collect field environmental data on a budget that permits citizen-scientists and researchers from low-income countries to collect the same high-quality data as researchers in wealthy countries. These data can provide information about global change to managers, governments, scientists, and interested citizens worldwide. Watertight box with ALog BottleLogger data logger on the left and battery pack with 3 D cells on the right. Data can be collected for 3-5 years on one set of batteries.
NASA Astrophysics Data System (ADS)
Ropert-Coudert, Yan; Knott, Nathan; Chiaradia, André; Kato, Akiko
2007-02-01
It is crucial in any bio-logging study to establish the potential effect that attachment of loggers may have on the animal. This ensures that the behaviour monitored by the loggers has a biological relevance, as well as for ethical reasons. Evaluation of the effects of externally attached loggers shows that they increase the drag of swimming animals and increase their energy expenditure. Nevertheless, little research has been done on the effects of size or position of such loggers. In this study, we tested whether the size (i.e. large: 4.9% versus small: 3.4% of the bird's frontal area) or the place of attachment (middle versus lower back) affected the diving behaviour of male and female little penguins ( Eudyptula minor). The positioning of the data logger on the middle or lower section of little penguins' back had little, if no effect, on the diving variables measured in this study. Size of the loggers, however, had strong effects. Birds with large loggers made shorter dives and reached shallower depths than those with small loggers. In addition, birds with large loggers made more dives probably to compensate for the extra cost of carrying a large logger. The measured variables also differed between the sexes, with males diving deeper and longer than females. Logger size had a sex-specific effect on the trip duration and descent speed, with males equipped with large loggers staying longer at sea than those with small loggers, and females with large loggers descending faster than those with small loggers. From our results, it appears that effects of logger position do not exist or are very small in comparison with the effects of logger size. The results of the current study indicate that the effects of size of loggers be evaluated more commonly in bio-logging research into the diving activity of free-ranging birds.
Tarity, T David; Koch, Chelsea N; Burket, Jayme C; Wright, Timothy M; Westrich, Geoffrey H
2017-03-01
Adverse local tissue reaction formation has been suggested to occur with the Modular Dual Mobility (MDM) acetabular design. Few reports in the literature have evaluated fretting and corrosion damage between the acetabular shell and modular metal inserts in this modular system. We evaluated a series of 18 retrieved cobalt chromium MDM inserts for evidence of fretting and corrosion. We assessed the backsides of 18 MDM components for evidence of fretting and corrosion in polar and taper regions based on previously established methods. We collected and assessed 30 similarly designed modular inserts retrieved from metal-on-metal (MoM) total hip arthroplasties as a control. No specific pattern of fretting or corrosion was identified on the MDM inserts. Both fretting and corrosion were significantly greater in the MoM cohort than the MDM cohort, driven by higher fretting and corrosion scores in the engaged taper region of the MoM inserts. MoM components demonstrated more fretting and corrosion than MDM designs, specifically at the taper region, likely driven by differences in the taper engagement mechanism and geometry among the insert designs. The lack of significant fretting and corrosion observed in the MDM inserts are inconsistent with recent claims that this interface may produce clinically significant metallosis and adverse local tissue reactions. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Sooby, Elizabeth; Balachandran, Shreyas; Foley, David; Hartwig, Karl; McIntyre, Peter; Phongikaroon, Supathorn; Pogue, Nathaniel; Simpson, Michael; Tripathy, Prabhat
2011-10-01
For an accelerator-driven subcritical molten salt fission core to survive its 50+ year fuel life, the primary vessel, heat exchanger, and various internal components must be made of materials that resist corrosion and radiation damage in a high-temperature environment, (500-800 C). An experimental study of the corrosion behavior of candidate metals in contact with molten salt is being conducted at the Center for Advanced Energy Studies. Initial experiments have been run on Nb, Ta, Ni, two zirconium alloys, Hastelloy-N, and a series of steel alloys to form a base line for corrosion in both chloride and bromide salt. Metal coupons were immersed in LiCl-KCl or LiBr-KBr at 700 C in an inert-atmosphere. Salt samples were extracted on a time schedule over a 24-hr period. The samples were analyzed using inductively coupled plasma-mass spectrometry to determine concentrations of metals from corrosion. Preliminary results will be presented.
Steel-free hybrid reinforcement system for concrete bridge decks, phase 1
DOT National Transportation Integrated Search
2006-05-01
Use of nonferrous fiber-reinforced polymer (FRP) reinforcement bars (rebars) offers one promising alternative to mitigating the corrosion problem in steel reinforced concrete bridge decks. Resistance to chloride ion driven corrosion, high tensile str...
Comparing the Methodologies in ASTM G198 Using Combined Hygrothermal-Corrosion Modeling
Samuel L. Zelinka
2013-01-01
ASTM G198, âStandard test method for determining the relative corrosion performance of driven fasteners in contact with treated wood,â was accepted by consensus and published in 2011. The method has two different exposure conditions for determining fastener corrosion performance in treated wood. The first method places the wood and embedded fasteners in a...
NASA Astrophysics Data System (ADS)
2012-07-01
WE RECOMMEND Data logger Fourier NOVA LINK: data logging and analysis To Engineer is Human Engineering: essays and insights Soap, Science, & Flat-Screen TVs People, politics, business and science overlap uLog sensors and sensor adapter A new addition to the LogIT range offers simplicity and ease of use WORTH A LOOK Imagined Worlds Socio-scientific predictions for the future Mini light data logger and mini temperature data logger Small-scale equipment for schools SensorLab Plus LogIT's supporting software, with extra features HANDLE WITH CARE CAXE110P PICAXE-18M2 data logger Data logger 'on view' but disappoints Engineering: A Very Short Introduction A broad-brush treatment fails to satisfy WEB WATCH Two very different websites for students: advanced physics questions answered and a more general BBC science resource
Information needs for increasing log transport efficiency
Timothy P. McDonald; Steven E. Taylor; Robert B. Rummer; Jorge Valenzuela
2001-01-01
Three methods of dispatching trucks to loggers were tested using a log transport simulation model: random allocation, fixed assignment of trucks to loggers, and dispatch based on knowledge of the current status of trucks and loggers within the system. This 'informed' dispatch algorithm attempted to minimize the difference in time between when a logger would...
ERIC Educational Resources Information Center
Barrett, Scott M.; Bolding, M. Chad; Munsell, John F.
2012-01-01
Virginia's SHARP logger program is a Cooperative Extension program currently providing training to over 1,500 loggers, foresters, and others. We conducted a mail survey of SHARP loggers to characterize program participants, assess programming needs, and evaluate program effectiveness. Results indicate a diverse group of participants in terms of…
Fuel supply structure of wood-fired power plants in the Northeast: Loggers' perspectives
Neil K. Huyler; Neil K. Huyler
1989-01-01
A study of loggers' perceptions of the impact of large biomass demand centers on the forest resource base in the Northeast indicated that most loggers strongly believe that the post-harvest stand has improved. However, the impact of whole-tree chipping on the forest resource base was not made clear from the loggers' survey.
NASA Astrophysics Data System (ADS)
Gillman, M. A.; Lamoureux, S. F.; Lafrenière, M. J.
2017-09-01
The Stream Temperature, Intermittency, and Conductivity (STIC) electrical conductivity (EC) logger as presented by Chapin et al. (2014) serves as an inexpensive (˜50 USD) means to assess relative EC in freshwater environments. This communication demonstrates the calibration of the STIC logger for quantifying EC, and provides examples from a month long field deployment in the High Arctic. Calibration models followed multiple nonlinear regression and produced calibration curves with high coefficient of determination values (R2 = 0.995 - 0.998; n = 5). Percent error of mean predicted specific conductance at 25°C (SpC) to known SpC ranged in magnitude from -0.6% to 13% (mean = -1.4%), and mean absolute percent error (MAPE) ranged from 2.1% to 13% (mean = 5.3%). Across all tested loggers we found good accuracy and precision, with both error metrics increasing with increasing SpC values. During 10, month-long field deployments, there were no logger failures and full data recovery was achieved. Point SpC measurements at the location of STIC loggers recorded via a more expensive commercial electrical conductivity logger followed similar trends to STIC SpC records, with 1:1.05 and 1:1.08 relationships between the STIC and commercial logger SpC values. These results demonstrate that STIC loggers calibrated to quantify EC are an economical means to increase the spatiotemporal resolution of water quality investigations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gunter, Dan; Lee, Jason; Stoufer, Martin
2003-03-28
The NetLogger Toolkit is designed to monitor, under actual operating conditions, the behavior of all the elements of the application-to-application communication path in order to determine exactly where time is spent within a complex system Using NetLogger, distnbuted application components are modified to produce timestamped logs of "interesting" events at all the critical points of the distributed system Events from each component are correlated, which allov^ one to characterize the performance of all aspects of the system and network in detail. The NetLogger Toolkit itself consists of four components an API and library of functions to simplify the generation ofmore » application-level event logs, a set of tools for collecting and sorting log files, an event archive system, and a tool for visualization and analysis of the log files In order to instrument an application to produce event logs, the application developer inserts calls to the NetLogger API at all the critical points in the code, then links the application with the NetLogger library All the tools in the NetLogger Toolkit share a common log format, and assume the existence of accurate and synchronized system clocks NetLogger messages can be logged using an easy-to-read text based format based on the lETF-proposed ULM format, or a binary format that can still be used through the same API but that is several times faster and smaller, with performance comparable or better than binary message formats such as MPI, XDR, SDDF-Binary, and PBIO. The NetLogger binary format is both highly efficient and self-describing, thus optimized for the dynamic message construction and parsing of application instrumentation. NetLogger includes an "activation" API that allows NetLogger logging to be turned on, off, or modified by changing an external file This IS useful for activating logging in daemons/services (e g GndFTP server). The NetLogger reliability API provides the ability to specify backup logging locations and penodically try to reconnect broken TCP pipe. A typical use for this is to store data on local disk while net is down. An event archiver can log one or more incoming NetLogger streams to a local disk file (netlogd) or to a mySQL database (netarchd). We have found exploratory, visual analysis of the log event data to be the most useful means of determining the causes of performance anomalies The NetLogger Visualization tool, niv, has been developed to provide a flexible and interactive graphical representation of system-level and application-level events.« less
Ludynia, Katrin; Dehnhard, Nina; Poisbleau, Maud; Demongin, Laurent; Masello, Juan F.; Quillfeldt, Petra
2012-01-01
Logger technology has revolutionised our knowledge of the behaviour and physiology of free-living animals but handling and logger attachments may have negative effects on the behaviour of the animals and their welfare. We studied southern rockhopper penguin (Eudyptes chrysocome) females during the guard stage in three consecutive breeding seasons (2008/09−2010/11) to evaluate the effects of handling and logger attachment on foraging trip duration, dive behaviour and physiological parameters. Smaller dive loggers (TDRs) were used in 2010/11 for comparison to larger GPS data loggers used in all three seasons and we included two categories of control birds: handled controls and PIT control birds that were previously marked with passive integrative transponders (PITs), but which had not been handled during this study. Increased foraging trip duration was only observed in GPS birds during 2010/11, the breeding season in which we also found GPS birds foraging further away from the colony and travelling longer distances. Compared to previous breeding seasons, 2010/11 may have been a period with less favourable environmental conditions, which would enhance the impact of logger attachments. A comparison between GPS and TDR birds showed a significant difference in dive depth frequencies with birds carrying larger GPS data loggers diving shallower. Mean and maximum dive depths were similar between GPS and TDR birds. We measured little impact of logger attachments on physiological parameters (corticosterone, protein, triglyceride levels and leucocyte counts). Overall, handling and short-term logger attachments (1–3 days) showed limited impact on the behaviour and physiology of the birds but care must be taken with the size of data loggers on diving seabirds. Increased drag may alter their diving behaviour substantially, thus constraining them in their ability to catch prey. Results obtained in this study indicate that data recorded may also not represent their normal dive behaviour. PMID:23185623
The design of a microprocessor-based data logger
Leap, K.J.; Dedini, L.A.
1982-01-01
The design of a microprocessor-based data logger, which collects and digitizes analog voltage signals from a continuous-measuring instrumentation system and transmits serial data to a magnetic tape recorder, is discussed. The data logger was assembled from commercially-available components and can be user-programmed for greater flexibility. A description of the data logger hardware and software designs, general operating instructions, the microprocessor program listing, and electrical schematic diagrams are presented.
Roles of Radiolytic and Externally Generated H2 in the Corrosion of Fractured Spent Nuclear Fuel.
Liu, Nazhen; Wu, Linda; Qin, Zack; Shoesmith, David W
2016-11-15
A 2-D model for the corrosion of spent nuclear fuel inside a failed nuclear waste container has been modified to determine the influence of various redox processes occurring within fractures in the fuel. The corrosion process is driven by reaction of the fuel with the dominant α radiolysis product, H 2 O 2 . A number of reactions are shown to moderate or suppress the corrosion rate, including H 2 O 2 decomposition and a number of reactions involving dissolved H 2 produced either by α radiolysis or by the corrosion of the steel container vessel. Both sources of H 2 lead to the suppression of fuel corrosion, with their relative importance being determined by the radiation dose rate, the steel corrosion rate, and the dimensions of the fractures in the fuel. The combination of H 2 from these two sources can effectively prevent corrosion when only micromolar quantities of H 2 are present.
Data-Logger Interface And Test Controller
NASA Technical Reports Server (NTRS)
Burch, Donnie R.
1995-01-01
Data-logger interface and test controller developed to enable automation of tests in conjunction with data-acquisition functions performed by data loggers that have output-switching capabilities. Includes relay logic circuits that remain deenergized until out-of-tolerance condition on any data channel discovered. Designed to be connected to Fluke model 2286A (or equivalent) data-logger system, which features 3 control channels with 6 data inputs per channel. Includes elapsed-time counter that keeps track of power outages.
Comparing the Methodologies in ASTM G198: Is There an Easy Way Out?
Samuel L. Zelinka
2013-01-01
ASTM(1) G198, Standard test method for determining the relative corrosion performance of driven fasteners in contact with treated wood, was accepted by consensus and published in 2011. The method has two different exposure conditions for determining fastener corrosion performance in treated wood. The first method places the wood and embedded...
NASA Astrophysics Data System (ADS)
Shin, Eunhye; Jin, Saera; Kim, Jiyoon; Chang, Sung-Jin; Jun, Byung-Hyuk; Park, Kwang-Won; Hong, Jongin
2016-08-01
K-doped TiO2 nanowire networks were prepared by the corrosion reaction of Ti nanoparticles in an alkaline (potassium hydroxide: KOH) solution. The prepared nanostructures were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, X-ray diffraction (XRD) and photoluminescence (PL) spectra. Their sunlight-driven photocatalytic activity was also investigated with differently charged dye molecules, such as methylene blue, rhodamine B and methyl orange. The adsorption of the dye molecules on the photocatalyst surface would play a critical role in their selective photodegradation under sunlight illumination.
Goldhawk, C; Crowe, T; González, L A; Janzen, E; Kastelic, J; Pajor, E; Schwartzkopf-Genswein, K
2014-09-01
Measuring animal-level conditions during transit provides information regarding the true risk of environmental challenges to cattle welfare during transportation. However, due to constraints on placing loggers at the animal level, there is a need to identify appropriate proxy locations. The objective was to evaluate 8 distributions of ceiling-level loggers in the deck and belly compartments of pot-belly trailers for assessing animal-level temperature and humidity during 5 to 18 h commercial transportation of feeder cattle. Ambient conditions during transportation ranged from 3.6 to 45.2°C (20.3 ± 7.61°C, mean ± SD). When considering the entire journey, average differences between ceiling and animal-level temperatures were similar among logger layouts (P > 0.05). The uncertainty in the difference in temperature and humidity between locations was high relative to the magnitude of the difference between animal- and ceiling-level conditions. Single-logger layouts required larger adjustments to predict animal-level conditions within either compartment, during either the entire journey or when the trailer was stationary (P < 0.05). Within certain logger layouts, there were small but significant differences in the ability of regression equations to predict animal-level conditions that were associated with cattle weight and available space relative to body size. Furthermore, evaluation of logger layouts based solely on the entire journey without consideration of stationary periods did not adequately capture variability in layout performance. In conclusion, to adequately monitor animal-level temperature and humidity, 10 loggers distributed throughout the compartment was recommended over single-logger layouts within both the deck and belly compartments of pot-belly trailers transporting feeder cattle in warm weather.
Design of an accurate wireless data logger for vibration analysis with Android interface.
Blanco, J R; Menéndez, J; Ferrero, F J; Campo, J C; Valledor, M
2016-12-01
In this work a new accurate wireless data logger using the Android interface was developed to monitor vibrations at low-cost. The new data logger is completely autonomous and extremely reduced in size. This instrument enables data collection wirelessly and the ability to display it on any tablet or smartphone with operating system Android. The prototype allows the monitoring of any industrial system with minimal investment in material and installation costs. The data logger is capable of making 12.8 kSPS enough to sample up to 5 kHz signals. The basic specification of the data logger includes a high resolution 1-axis piezoelectric accelerometer with a working range of ±30 G. In addition to the acceleration measurements, temperature can also be recorded. The data logger was tested during a 6-month period in industrial environments. The details of the specific hardware and software design are described. The proposed technology can be easily transferred to many other areas of industrial monitoring.
Optimising crime scene temperature collection for forensic entomology casework.
Hofer, Ines M J; Hart, Andrew J; Martín-Vega, Daniel; Hall, Martin J R
2017-01-01
The value of minimum post-mortem interval (minPMI) estimations in suspicious death investigations from insect evidence using temperature modelling is indisputable. In order to investigate the reliability of the collected temperature data used for modelling minPMI, it is necessary to study the effects of data logger location on the accuracy and precision of measurements. Digital data logging devices are the most commonly used temperature measuring devices in forensic entomology, however, the relationship between ambient temperatures (measured by loggers) and body temperatures has been little studied. The placement of loggers in this study in three locations (two outdoors, one indoors) had measurable effects when compared with actual body temperature measurements (simulated with pig heads), some more significant than others depending on season, exposure to the environment and logger location. Overall, the study demonstrated the complexity of the question of optimal logger placement at a crime scene and the potential impact of inaccurate temperature data on minPMI estimations, showing the importance of further research in this area and development of a standard protocol. Initial recommendations are provided for data logger placement (within a Stevenson Screen where practical), situations to avoid (e.g. placement of logger in front of windows when measuring indoor temperatures), and a baseline for further research into producing standard guidelines for logger placement, to increase the accuracy of minPMI estimations and, thereby, the reliability of forensic entomology evidence in court. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Shipboard Analytical Capabilities on the Renovated JOIDES Resolution, IODP Riserless Drilling Vessel
NASA Astrophysics Data System (ADS)
Blum, P.; Foster, P.; Houpt, D.; Bennight, C.; Brandt, L.; Cobine, T.; Crawford, W.; Fackler, D.; Fujine, K.; Hastedt, M.; Hornbacher, D.; Mateo, Z.; Moortgat, E.; Vasilyev, M.; Vasilyeva, Y.; Zeliadt, S.; Zhao, J.
2008-12-01
The JOIDES Resolution (JR) has conducted 121 scientific drilling expeditions during the Ocean Drilling Program (ODP) and the first phase of the Integrated Ocean Drilling Program (IODP) (1983-2006). The vessel and scientific systems have just completed an NSF-sponsored renovation (2005-2008). Shipboard analytical systems have been upgraded, within funding constraints imposed by market driven vessel conversion cost increases, to include: (1) enhanced shipboard analytical services including instruments and software for sampling and the capture of chemistry, physical properties, and geological data; (2) new data management capabilities built around a laboratory information management system (LIMS), digital asset management system, and web services; (3) operations data services with enhanced access to navigation and rig instrumentation data; and (4) a combination of commercial and home-made user applications for workflow- specific data extractions, generic and customized data reporting, and data visualization within a shipboard production environment. The instrumented data capture systems include a new set of core loggers for rapid and non-destructive acquisition of images and other physical properties data from drill cores. Line-scan imaging and natural gamma ray loggers capture data at unprecedented quality due to new and innovative designs. Many instruments used to characterize chemical compounds of rocks, sediments, and interstitial fluids were upgraded with the latest technology. The shipboard analytical environment features a new and innovative framework (DESCinfo) and application (DESClogik) for capturing descriptive and interpretive data from geological sub-domains such as sedimentology, petrology, paleontology, structural geology, stratigraphy, etc. This system fills a long-standing gap by providing a global database, controlled vocabularies and taxa name lists with version control, a highly configurable spreadsheet environment for data capture, and visualization of context data collected with the shipboard core loggers and other instruments.
Measuring stream temperature with digital data loggers: a user's guide
Jason Dunham; Gwynne Chandler; Bruce Rieman; Don Martin
2005-01-01
Digital data loggers (thermographs) are among the most widespread instruments in use for monitoring physical conditions in aquatic ecosystems. The intent of this protocol is to provide guidelines for selecting and programming data loggers, sampling water temperatures in the field, data screening and analysis, and data archiving.
Controlling sediment collection with data loggers
Rand E. Eads
1991-01-01
Abstract - The proliferation of commercial non-programmable data loggers in the past five years has done little to increase sediment sampling efficiency in remote locations. Recent advances in microelectronics have encouraged the development of commercial, low-power, programmable data loggers at reasonable cost. Although some facets of hydrologic data collection may...
Wang, Haibo; Hu, Chun; Zhang, Lili; Li, Xiaoxiao; Zhang, Yu; Yang, Min
2014-11-15
Bacterial characteristics in corrosion products and their effect on the formation of dense corrosion scales on cast iron coupons were studied in drinking water, with sterile water acting as a reference. The corrosion process and corrosion scales were characterized by electrochemical and physico-chemical measurements. The results indicated that the corrosion was more rapidly inhibited and iron release was lower due to formation of more dense protective corrosion scales in drinking water than in sterile water. The microbial community and denitrifying functional genes were analyzed by pyrosequencing and quantitative polymerase chain reactions (qPCR), respectively. Principal component analysis (PCA) showed that the bacteria in corrosion products played an important role in the corrosion process in drinking water. Nitrate-reducing bacteria (NRB) Acidovorax and Hydrogenophaga enhanced iron corrosion before 6 days. After 20 days, the dominant bacteria became NRB Dechloromonas (40.08%) with the protective corrosion layer formation. The Dechloromonas exhibited the stronger corrosion inhibition by inducing the redox cycling of iron, to enhance the precipitation of iron oxides and formation of Fe3O4. Subsequently, other minor bacteria appeared in the corrosion scales, including iron-respiring bacteria and Rhizobium which captured iron by the produced siderophores, having a weaker corrosion-inhibition effect. Therefore, the microbially-driven redox cycling of iron with associated microbial capture of iron caused more compact corrosion scales formation and lower iron release. Copyright © 2014 Elsevier Ltd. All rights reserved.
Assessing safety awareness and knowledge and behavioral change among West Virginia loggers
Helmkamp, J; Bell, J; Lundstrom, W; Ramprasad, J; Haque, A
2004-01-01
Objective: To determine if a video used during logger training influences safety attitude, knowledge, and workplace habits. Method: From April 2002 to October 2003, loggers receiving training through the West Virginia Division of Forestry were given a new safety module. This consisted of a pre-training survey, viewing video, brief introduction to field safety guide, and an immediate post-training survey. Six months after training, loggers were contacted by telephone to assess workplace behavioral changes. Results: 1197 loggers attended 80 training sessions and completed surveys; 21% were contacted at follow up. Pre-training surveys indicated that half said "accidents" were part of the job and had experienced a "close call" in their work. An overwhelming majority felt that safety management and periodic meetings were important. Over 75% indicated they would not take risks in order to make a profit. Several statistically significant improvements were noted in safety knowledge after viewing the video: logger's location in relation to the tree stump during fatal incidents and the pictorial identification of an overloaded truck and the safest cutting notch. At follow up, many of the loggers said they related to the real life victim stories portrayed in the video. Further, the field guide served as a quick and easy reference and taught them valuable tips on safe cutting and felling. Conclusions: Significant changes in safety knowledge and attitude among certified loggers resulted from viewing the video during training. Subsequent use of the video and field guide at the worksite encouraged positive change in self reported work habits and practices. PMID:15314051
NASA Astrophysics Data System (ADS)
Anderson, T.; Jencso, K. G.; Hoylman, Z. H.; Hu, J.
2015-12-01
Characterizing the mechanisms that lead to differences in forest ecosystem productivity across complex terrain remains a challenge. This difficulty can be partially attributed to the cost of installing networks of proprietary data loggers that monitor differences in the biophysical factors contributing to tree growth. Here, we describe the development and initial application of a network of open source data loggers. These data loggers are based on the Arduino platform, but were refined into a custom printed circuit board (PCB). This reduced the cost and complexity of the data loggers, which made them cheap to reproduce and reliable enough to withstand the harsh environmental conditions experienced in Ecohydrology studies. We demonstrate the utility of these loggers for high frequency, spatially-distributed measurements of sap-flux, stem growth, relative humidity, temperature, and soil water content across 36 landscape positions in the Lubrecht Experimental Forest, MT, USA. This new data logging technology made it possible to develop a spatially distributed monitoring network within the constraints of our research budget and may provide new insights into factors affecting forest productivity across complex terrain.
The Gem Infrasound Logger and Custom-Built Instrumentation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Jacob F.; Johnson, Jeffrey B.; Bowman, Daniel C.
Here, we designed, built, and recorded data with a custom infrasound logger (referred to as the Gem) that is inexpensive, portable, and easy to use. We also describe its design process, qualities, and applications in this article. Field instrumentation is a key element of geophysical data collection, and the quantity and quality of data that can be recorded is determined largely by the characteristics of the instruments used. Geophysicists tend to rely on commercially available instruments, which suffice for many important types of fieldwork. However, commercial instrumentation can fall short in certain roles, which motivates the development of custom sensorsmore » and data loggers. Particularly, we found existing data loggers to be expensive and inconvenient for infrasound campaigns, and developed the Gem infrasound logger in response. In this article, we discuss development of this infrasound logger and the various uses found for it, including projects on volcanoes, high-altitude balloons, and rivers. Further, we demonstrate that when needed, scientists can feasibly design and build their own specialized instruments, and that doing so can enable them to record more and better data at a lower cost.« less
The Gem Infrasound Logger and Custom-Built Instrumentation
Anderson, Jacob F.; Johnson, Jeffrey B.; Bowman, Daniel C.; ...
2017-11-22
Here, we designed, built, and recorded data with a custom infrasound logger (referred to as the Gem) that is inexpensive, portable, and easy to use. We also describe its design process, qualities, and applications in this article. Field instrumentation is a key element of geophysical data collection, and the quantity and quality of data that can be recorded is determined largely by the characteristics of the instruments used. Geophysicists tend to rely on commercially available instruments, which suffice for many important types of fieldwork. However, commercial instrumentation can fall short in certain roles, which motivates the development of custom sensorsmore » and data loggers. Particularly, we found existing data loggers to be expensive and inconvenient for infrasound campaigns, and developed the Gem infrasound logger in response. In this article, we discuss development of this infrasound logger and the various uses found for it, including projects on volcanoes, high-altitude balloons, and rivers. Further, we demonstrate that when needed, scientists can feasibly design and build their own specialized instruments, and that doing so can enable them to record more and better data at a lower cost.« less
Schüller, Laura K; Heuwieser, Wolfgang
2016-08-01
The objectives of this study were to examine heat stress conditions at cow level and to investigate the relationship to the climate conditions at 5 different stationary locations inside a dairy barn. In addition, we compared the climate conditions at cow level between primiparous and multiparous cows for a period of 1 week after regrouping. The temperature-humidity index (THI) differed significantly between all stationary loggers. The lowest THI was measured at the window logger in the experimental stall and the highest THI was measured at the central logger in the experimental stall. The THI at the mobile cow loggers was 2·33 THI points higher than at the stationary loggers. Furthermore, the mean daily THI was higher at the mobile cow loggers than at the stationary loggers on all experimental days. The THI in the experimental pen was 0·44 THI points lower when the experimental cow group was located inside the milking parlour. The THI measured at the mobile cow loggers was 1·63 THI points higher when the experimental cow group was located inside the milking parlour. However, there was no significant difference for all climate variables between primiparous and multiparous cows. These results indicate, there is a wide range of climate conditions inside a dairy barn and especially areas with a great distance to a fresh air supply have an increased risk for the occurrence of heat stress conditions. Furthermore, the heat stress conditions are even higher at cow level and cows not only influence their climatic environment, but also generate microclimates within different locations inside the barn. Therefore climate conditions should be obtained at cow level to evaluate the heat stress conditions that dairy cows are actually exposed to.
A Data-Based Console Logger for Mission Operations Team Coordination
NASA Technical Reports Server (NTRS)
Thronesbery, Carroll; Malin, Jane T.; Jenks, Kenneth; Overland, David; Oliver, Patrick; Zhang, Jiajie; Gong, Yang; Zhang, Tao
2005-01-01
Concepts and prototypes1,2 are discussed for a data-based console logger (D-Logger) to meet new challenges for coordination among flight controllers arising from new exploration mission concepts. The challenges include communication delays, increased crew autonomy, multiple concurrent missions, reduced-size flight support teams that include multidisciplinary flight controllers during quiescent periods, and migrating some flight support activities to flight controller offices. A spiral development approach has been adopted, making simple, but useful functions available early and adding more extensive support later. Evaluations have guided the development of the D-Logger from the beginning and continue to provide valuable user influence about upcoming requirements. D-Logger is part of a suite of tools designed to support future operations personnel and crew. While these tools can be used independently, when used together, they provide yet another level of support by interacting with one another. Recommendations are offered for the development of similar projects.
Andrew D. George; Frank R. Thompson; John. Faaborg
2015-01-01
A spatial mismatch exists between regional climate models and conditions experienced by individual organisms. We demonstrate an approach to downscaling air temperatures for site-level studies using airborne LiDAR data and remote microclimate loggers. In 2012-2013, we established a temperature logger network in the forested region of central Missouri, USA, and obtained...
Review and study of physics driven pitting corrosion modeling in 2024-T3 aluminum alloys
NASA Astrophysics Data System (ADS)
Yu, Lingyu; Jata, Kumar V.
2015-04-01
Material degradation due to corrosion and corrosion fatigue has been recognized to significantly affect the airworthiness of civilian and military aircraft, especially for the current fleet of airplanes that have served beyond their initial design life. The ability to predict the corrosion damage development in aircraft components and structures, therefore, is of great importance in managing timely maintenance for the aging aircraft vehicles and in assisting the design of new ones. The assessment of aircraft corrosion and its influence on fatigue life relies on appropriate quantitative models that can evaluate the initiation of the corrosion as well as the accumulation during the period of operation. Beyond the aircraft regime, corrosion has also affected the maintenance, safety and reliability of other systems such as nuclear power systems, steam and gas turbines, marine structures and so on. In the work presented in this paper, we reviewed and studied several physics based pitting corrosion models that have been reported in the literature. The classic work of particle induced pitting corrosion by Wei and Harlow is reviewed in detail. Two types of modeling, a power law based simplified model and a microstructure based model, are compared for 2024-T3 alloy. Data from literatures are used as model inputs. The paper ends with conclusions and recommendations for future work.
Yanshu Li; Daowei Zhang
2010-01-01
A framework was developed to estimate the welfare incidence of the 1996 U.S.-Canada Softwood Lumber Agreement among producers in two-processing-stage markets--timberland owners, loggers, and lumber manufacturers--in the U.S. South. Timberland owners are the largest beneficiary whereas lumber manufacturers are the second and loggers the least. Empirically, without...
Samuel L. Zelinka
2007-01-01
This paper evaluates the effect that uncertainties in measurements of time, weight, and surface area have on the determination of the corrosion rate of metal fasteners in contact with wood. Three different types of nails were driven into alkaline copper quaternary (ACQ)-treated wood and exposed to 26.7°C (80°C) at 100 % relative humidity environment for up to 1 year....
Worldwide Research, Worldwide Participation: Web-Based Test Logger
NASA Technical Reports Server (NTRS)
Clark, David A.
1998-01-01
Thanks to the World Wide Web, a new paradigm has been born. ESCORT (steady state data system) facilities can now be configured to use a Web-based test logger, enabling worldwide participation in tests. NASA Lewis Research Center's new Web-based test logger for ESCORT automatically writes selected test and facility parameters to a browser and allows researchers to insert comments. All data can be viewed in real time via Internet connections, so anyone with a Web browser and the correct URL (universal resource locator, or Web address) can interactively participate. As the test proceeds and ESCORT data are taken, Web browsers connected to the logger are updated automatically. The use of this logger has demonstrated several benefits. First, researchers are free from manual data entry and are able to focus more on the tests. Second, research logs can be printed in report format immediately after (or during) a test. And finally, all test information is readily available to an international public.
A Custom Data Logger for Real-Time Remote Field Data Collections
2017-03-01
ERDC/CHL CHETN-VI-46 March 2017 Approved for public release; distribution is unlimited. A Custom Data Logger for Real- Time Remote Field Data...Field Research Facility (FRF), for remote real- time data collections. This custom data logger is compact and energy efficient but has the same...INTRODUCTION: Real- time data collections offer many advantages: 1. Instrument failures can be rapidly detected and repaired, thereby minimizing
Progress on Component Evaluation for Nuclear Explosion Monitoring
2008-09-01
one data logger, Geotech Smart24. For the infrasound sensors tested, the test results allow us to conclude that both sensors had sufficiently quiet...a lower frequency than expected. Sandia was also asked to evaluate the Geotech Smart24 data logger for qualification as a replacement to the Geotech ...results of using 26-bit quantization. Characterization Geotech Smart24 Data-Logger with Active Fortezza Crypto Card Data Signing Over the spring
Monitoring stream temperatures—A guide for non-specialists
Heck, Michael P.; Schultz, Luke D.; Hockman-Wert, David; Dinger, Eric C.; Dunham, Jason B.
2018-04-19
Executive SummaryWater temperature influences most physical and biological processes in streams, and along with streamflows is a major driver of ecosystem processes. Collecting data to measure water temperature is therefore imperative, and relatively straightforward. Several protocols exist for collecting stream temperature data, but these are frequently directed towards specialists. This document was developed to address the need for a protocol intended for non-specialists (non-aquatic) staff. It provides specific step-by-step procedures on (1) how to launch data loggers, (2) check the factory calibration of data loggers prior to field use, (3) how to install data loggers in streams for year-round monitoring, (4) how to download and retrieve data loggers from the field, and (5) how to input project data into organizational databases.
Ethernet based data logger for gaseous detectors
NASA Astrophysics Data System (ADS)
Swain, S.; Sahu, P. K.; Sahu, S. K.
2018-05-01
A data logger is designed to monitor and record ambient parameters such as temperature, pressure and relative humidity along with gas flow rate as a function of time. These parameters are required for understanding the characteristics of gas-filled detectors such as Gas Electron Multiplier (GEM) and Multi-Wire Proportional Counter (MWPC). The data logger has different microcontrollers and has been interfaced to an ethernet port with a local LCD unit for displaying all measured parameters. In this article, the explanation of the data logger design, hardware, and software description of the master microcontroller and the DAQ system along with LabVIEW interface client program have been presented. We have implemented this device with GEM detector and displayed few preliminary results as a function of above parameters.
2014-06-01
Even well- controlled laboratory testing saw a range of COV from less than 10 percent to over 500 percent for different steels (Tryon & Cruse...identified. This 6-year limit is driven by concerns about corrosion fatigue , a process initiated by water gaining access to the carbon steel of the shaft...physics and is controlled by different parameters and interactions of the many variables involved. Figure 2 depicts the corrosion fatigue sequence of
Inexpensive, Low Power, Open-Source Data Logging hardware development
NASA Astrophysics Data System (ADS)
Sandell, C. T.; Schulz, B.; Wickert, A. D.
2017-12-01
Over the past six years, we have developed a suite of open-source, low-cost, and lightweight data loggers for scientific research. These loggers employ the popular and easy-to-use Arduino programming environment, but consist of custom hardware optimized for field research. They may be connected to a broad and expanding range of off-the-shelf sensors, with software support built in directly to the "ALog" library. Three main models exist: The ALog (for Autonomous or Arduino Logger) is the extreme low-power model for years-long deployments with only primary AA or D batteries. The ALog shield is a stripped-down ALog that nests with a standard Arduino board for prototyping or education. The TLog (for Telemetering Logger) contains an embedded radio with 500 m range and a GPS for communications and precision timekeeping. This enables meshed networks of loggers that can send their data back to an internet-connected "home base" logger for near-real-time field data retrieval. All boards feature feature a high-precision clock, full size SD card slot for high-volume data storage, large screw terminals to connect sensors, interrupts, SPI and I2C communication capability, and 3.3V/5V power outputs. The ALog and TLog have fourteen 16-bit analog inputs with a precision voltage reference for precise analog measurements. Their components are rated -40 to +85 degrees C, and they have been tested in harsh field conditions. These low-cost and open-source data loggers have enabled our research group to collect field data across North and South America on a limited budget, support student projects, and build toward better future scientific data systems.
Wright, Richard L.; Zillmer, Ruediger; Biran, Adam; Hall, Peter; Sidibe, Myriam
2015-01-01
We evaluated the utility of electronic loggers to measure the effects of a simple intervention designed to influence the rates of hand washing with soap within enclosed toilets and bathrooms in low-income urban households in Kerala, India. 58 households were given three items with embedded electronic loggers for a period of 2-5 days. Two logged soaps tracked hand and body washing in the bathroom. The third logged item was a water vessel used for flushing the toilet and for post-defecation anal cleansing; this served as a marker of toilet use. In addition, 28 households in a Soap by toilet arm were given an additional logged soap, to be kept by the toilet, and used for hand washing. Compared with the Soap in bathroom arm, the loggers in the Soap by toilet households recorded 73% greater daily use of soaps designated for hand washing (t(36)=2.92, p<0.01) and 172% greater use within 2 minutes of the use of the water vessel (t(36)=3.51, p = 0.001). We conclude that the loggers were capable of detecting changes in the rates of hand washing with soap and changes in hand washing with soap after use of the toilet. Further adoption of logger technologies would enable more insightful studies of hand washing within urban environments. PMID:26101886
Wright, Richard L; Zillmer, Ruediger; Biran, Adam; Hall, Peter; Sidibe, Myriam
2015-01-01
We evaluated the utility of electronic loggers to measure the effects of a simple intervention designed to influence the rates of hand washing with soap within enclosed toilets and bathrooms in low-income urban households in Kerala, India. 58 households were given three items with embedded electronic loggers for a period of 2-5 days. Two logged soaps tracked hand and body washing in the bathroom. The third logged item was a water vessel used for flushing the toilet and for post-defecation anal cleansing; this served as a marker of toilet use. In addition, 28 households in a Soap by toilet arm were given an additional logged soap, to be kept by the toilet, and used for hand washing. Compared with the Soap in bathroom arm, the loggers in the Soap by toilet households recorded 73% greater daily use of soaps designated for hand washing (t(36)=2.92, p<0.01) and 172% greater use within 2 minutes of the use of the water vessel (t(36)=3.51, p = 0.001). We conclude that the loggers were capable of detecting changes in the rates of hand washing with soap and changes in hand washing with soap after use of the toilet. Further adoption of logger technologies would enable more insightful studies of hand washing within urban environments.
Carter, Stephen P.; Bearhop, Stuart; Harrison, Xavier A.; Dall, Sasha R. X.; McDonald, Robbie A.; Delahay, Richard J.
2012-01-01
Knowledge of the way in which animals interact through social networks can help to address questions surrounding the ecological and evolutionary consequences of social organisation, and to understand and manage the spread of infectious diseases. Automated proximity loggers are increasingly being used to record interactions between animals, but the accuracy and reliability of the collected data remain largely un-assessed. Here we use laboratory and observational field data to assess the performance of these devices fitted to a herd of 32 beef cattle (Bos taurus) and nine groups of badgers (Meles meles, n = 77) living in the surrounding woods. The distances at which loggers detected each other were found to decrease over time, potentially related to diminishing battery power that may be a function of temperature. Loggers were highly accurate in recording the identification of contacted conspecifics, but less reliable at determining contact duration. There was a tendency for extended interactions to be recorded as a series of shorter contacts. We show how data can be manipulated to correct this discrepancy and accurately reflect observed interaction patterns by combining records between any two loggers that occur within a 1 to 2 minute amalgamation window, and then removing any remaining 1 second records. We make universally applicable recommendations for the effective use of proximity loggers, to improve the validity of data arising from future studies. PMID:22745704
Nelson, Eric D; Huang, Henry
2011-03-01
The utility of temperature/humidity data loggers are evaluated as a low-cost approach to enrich practical understanding of the actual time dependent humidity that a pharmaceutical product is exposed to. While this approach is found to have significant utility in general, small systematic biases in the measurements due to the presence of the data logger are observed. Taking these biases into account enables more productive extrapolation of measured time/humidity profiles. © 2011 American Association of Pharmaceutical Scientists
Robert B. Rummer
1997-01-01
Logging is facing a world of change. A logger?s niche can be defined by terrain, climate, location, timber and product, local government, Federal government, landowners, and mills. The author offers strategies for survival and successful competition.
Mor-Bell Logger: Skidding Case Study
Bryce J. Stokes; Jerry L. Koger; Frank J. Pickle
1983-01-01
A production equation was developed for the Mor-Bell logger for skidding while thinning a loblolly pine plantation. Production and costs for skidding and iron gate delimbing were determined for a range of operating conditions.
Application of vaginal temperature measurement in bitches.
Maeder, B; Arlt, S; Burfeind, O; Heuwieser, W
2012-12-01
Finding innovative, non-invasive methods for continuously measuring body temperature minimizing human interference is important for accurate data collection. The objective of this study was to assess feasibility and accuracy of continuous body temperature measurements with loggers placed in the vaginal cavity of bitches. First, an in vitro experiment was performed to compare values obtained by temperature loggers (n = 26) to a calibrated liquid-in-glass thermometer. The mean differences between the two methods were low. Next, an in vivo experiment was performed using five healthy bitches, and values obtained by the vaginal loggers were compared to measurements collected rectally with digital thermometers. The results show that rectal and vaginal temperatures were correlated. The mean differences between rectal and vaginal temperatures were negligible. We conclude that the utilized temperature loggers provide accurate and reliable data. © 2012 Blackwell Verlag GmbH.
Coliform culturability in over- versus undersaturated drinking waters.
Grandjean, D; Fass, S; Tozza, D; Cavard, J; Lahoussine, V; Saby, S; Guilloteau, H; Block, J-C
2005-05-01
The culturability of Escherichia coli in undersaturated drinking water with respect to CaCO3 (corrosive water) or in oversaturated water (non-corrosive water) was tested in different reactors: glass flasks (batch, "non-reactive" wall); glass reactors (chemostat, "non-reactive" wall) versus a corroded cast iron Propella reactor (chemostat, "reactive" wall) and a 15-year-old distribution system pilot (chemostat, "reactive" wall with 1% corroded cast iron and 99% cement-lined cast iron). The E. coli in E. coli-spiked drinking water was not able to maintain its culturability and colonize the experimental systems. It appears from our results that the optimal pH for maintaining E. coli culturability was around 8.2 or higher. However, in reactors with a reactive wall (corroded cast iron), the decline in E. coli culturability was slower when the pH was adjusted to 7.9 or 7.7 (i.e. a reactor fed with corrosive water; pH
Data logger technologies for manual wheelchairs: A scoping review.
Routhier, François; Lettre, Josiane; Miller, William C; Borisoff, Jaimie F; Keetch, Kate; Mitchell, Ian M; Research Team, CanWheel
2018-01-01
In recent years, studies have increasingly employed data logger technologies to record objective driving and physiological characteristics of manual wheelchair users. However, the technologies used offer significant differences in characteristics, such as measured outcomes, ease of use, and level of burden. In order to identify and describe the extent of published research activity that relies on data logger technologies for manual wheelchair users, we performed a scoping review of the scientific and gray literature. Five databases were searched: Medline, Compendex, CINAHL, EMBASE, and Google Scholar. The 119 retained papers document a wide variety of logging devices and sensing technologies measuring a range of outcomes. The most commonly used technologies were accelerometers installed on the user (18.8%), odometers installed on the wheelchair (12.4%), accelerometers installed on the wheelchair (9.7%), and heart monitors (9.7%). Not surprisingly, the most reported outcomes were distance, mobility events, heart rate, speed/velocity, acceleration, and driving time. With decreasing costs and technological improvements, data loggers are likely to have future widespread clinical (and even personal) use. Future research may be needed to assess the usefulness of different outcomes and to develop methods more appropriate to wheelchair users in order to optimize the practicality of wheelchair data loggers.
The effect of spiked boots on logger safety, productivity and workload.
Kirk, P; Parker, R
1994-04-01
Analysis of 1657 lost-time logging accidents in the New Zealand logging industry (1985-1991) indicates that 17.5% were as a result of slips, trips and falls and a total of 2870 days were lost. Most (56%) of these slipping, tripping and falling accidents occurred in the felling and delimbing phase of the logging operation, where 37% of the workforce are employed. In an attempt to reduce the number of slipping injuries to loggers employed in felling and delimbing, a study of the effectiveness of spike-soled (caulk) boots was undertaken. Four loggers were intensively observed at work, by continuous time-study methods, while wearing their conventional rubber-soled boots and then spike-soled boots. The number of slips, work methods used, physiological workload and productivity were compared for loggers wearing the two footwear types. Results indicated that spike-soled boots were associated with a significant reduction in the frequency of slips and had no adverse effect on work methods, physiological workload or productivity. Spike-soled boots are now being promoted for use by loggers in New Zealand as a simple method to reduce slipping, tripping and falling accidents.
Studies on Materials for Heavy-Liquid-Metal-Cooled Reactors in Japan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Minoru Takahashi; Masayuki Igashira; Toru Obara
2002-07-01
Recent studies on materials for the development of lead-bismuth (Pb-Bi)-cooled fast reactors (FR) and accelerator-driven sub-critical systems (ADS) in Japan are reported. The measurement of the neutron cross section of Bi to produce {sup 210}Po, the removal experiment of Po contamination and steel corrosion test in Pb-Bi flow were performed in Tokyo Institute of Technology. A target material corrosion test was performed in the project of Transmutation Experimental Facility for ADS in Japan Atomic Energy Research Institute (JAERI). Steel corrosion test was started in Mitsui Engineering and Shipbuilding Co., LTD (MES). The feasibility study for FR cycle performed in Japanmore » Nuclear Cycle Institute (JNC) are described. (authors)« less
Walker, Robert; Arima, Eugenio; Messina, Joe; Soares-Filho, Britaldo; Perz, Stephen; Vergara, Dante; Sales, Marcio; Pereira, Ritaumaria; Castro, Williams
2013-01-01
This article addresses the spatial decision-making of loggers and implications for forest fragmentation in the Amazon basin. It provides a behavioral explanation for fragmentation by modeling how loggers build road networks, typically abandoned upon removal of hardwoods. Logging road networks provide access to land, and the settlers who take advantage of them clear fields and pastures that accentuate their spatial signatures. In shaping agricultural activities, these networks organize emergent patterns of forest fragmentation, even though the loggers move elsewhere. The goal of the article is to explicate how loggers shape their road networks, in order to theoretically explain an important type of forest fragmentation found in the Amazon basin, particularly in Brazil. This is accomplished by adapting graph theory to represent the spatial decision-making of loggers, and by implementing computational algorithms that build graphs interpretable as logging road networks. The economic behavior of loggers is conceptualized as a profit maximization problem, and translated into spatial decision-making by establishing a formal correspondence between mathematical graphs and road networks. New computational approaches, adapted from operations research, are used to construct graphs and simulate spatial decision-making as a function of discount rates, land tenure, and topographic constraints. The algorithms employed bracket a range of behavioral settings appropriate for areas of terras de volutas, public lands that have not been set aside for environmental protection, indigenous peoples, or colonization. The simulation target sites are located in or near so-called Terra do Meio, once a major logging frontier in the lower Amazon Basin. Simulation networks are compared to empirical ones identified by remote sensing and then used to draw inferences about factors influencing the spatial behavior of loggers. Results overall suggest that Amazonia's logging road networks induce more fragmentation than necessary to access fixed quantities of wood. The paper concludes by considering implications of the approach and findings for Brazil's move to a system of concession logging.
Carnley, Mark V.
2015-01-01
The Pressure Water Level Data Logger manufactured by Infinities USA, Inc., was evaluated by the U.S. Geological Survey (USGS) Hydrologic Instrumentation Facility for conformance with the manufacturer’s stated accuracy specifications for measuring pressure throughout the device’s operating temperature range and with the USGS accuracy requirements for water-level measurements. The Pressure Water Level Data Logger (Infinities Logger) is a submersible, sealed, water-level sensing device with an operating pressure range of 0 to 11.5 feet of water over a temperature range of −18 to 49 degrees Celsius. For the pressure range tested, the manufacturer’s accuracy specification of 0.1 percent of full scale pressure equals an accuracy of ±0.138 inch of water. Three Infinities Loggers were evaluated, and the testing procedures followed and results obtained are described in this report. On the basis of the test results, the device is poorly compensated for temperature. For the three Infinities Loggers, the mean pressure differences varied from –4.04 to 5.32 inches of water and were not within the manufacturer’s accuracy specification for pressure measurements made within the temperature-compensated range. The device did not meet the manufacturer’s stated accuracy specifications for pressure within its temperature-compensated operating range of –18 to 49 degrees Celsius or the USGS accuracy requirements of no more than 0.12 inch of water (0.01 foot of water) or 0.10 percent of reading, whichever is larger. The USGS accuracy requirements are routinely examined and reported when instruments are evaluated at the Hydrologic Instrumentation Facility. The estimated combined measurement uncertainty for the pressure cycling test was ±0.139 inch of water, and for temperature, the cycling test was ±0.127 inch of water for the three Infinities Loggers.
Beddows, Patricia A; Mallon, Edward K
2018-02-09
A low-cost data logging platform is presented that provides long-term operation in remote or submerged environments. Three premade "breakout boards" from the open-source Arduino ecosystem are assembled into the core of the data logger. Power optimization techniques are presented which extend the operational life of this module-based design to >1 year on three alkaline AA batteries. Robust underwater housings are constructed for these loggers using PVC fittings. Both the logging platform and the enclosures, are easy to build and modify without specialized tools or a significant background in electronics. This combination turns the Cave Pearl data logger into a generalized prototyping system and this design flexibility is demonstrated with two field studies recording drip rates in a cave and water flow in a flooded cave system. This paper describes a complete DIY solution, suitable for a wide range of challenging deployment conditions.
Mallon, Edward K.
2018-01-01
A low-cost data logging platform is presented that provides long-term operation in remote or submerged environments. Three premade “breakout boards” from the open-source Arduino ecosystem are assembled into the core of the data logger. Power optimization techniques are presented which extend the operational life of this module-based design to >1 year on three alkaline AA batteries. Robust underwater housings are constructed for these loggers using PVC fittings. Both the logging platform and the enclosures, are easy to build and modify without specialized tools or a significant background in electronics. This combination turns the Cave Pearl data logger into a generalized prototyping system and this design flexibility is demonstrated with two field studies recording drip rates in a cave and water flow in a flooded cave system. This paper describes a complete DIY solution, suitable for a wide range of challenging deployment conditions. PMID:29425185
da Cunha, Antonio Ribeiro
2015-05-01
This study aimed to assess measurements of temperature and relative humidity obtained with HOBO a data logger, under various conditions of exposure to solar radiation, comparing them with those obtained through the use of a temperature/relative humidity probe and a copper-constantan thermocouple psychrometer, which are considered the standards for obtaining such measurements. Data were collected over a 6-day period (from 25 March to 1 April, 2010), during which the equipment was monitored continuously and simultaneously. We employed the following combinations of equipment and conditions: a HOBO data logger in full sunlight; a HOBO data logger shielded within a white plastic cup with windows for air circulation; a HOBO data logger shielded within a gill-type shelter (multi-plate prototype plastic); a copper-constantan thermocouple psychrometer exposed to natural ventilation and protected from sunlight; and a temperature/relative humidity probe under a commercial, multi-plate radiation shield. Comparisons between the measurements obtained with the various devices were made on the basis of statistical indicators: linear regression, with coefficient of determination; index of agreement; maximum absolute error; and mean absolute error. The prototype multi-plate shelter (gill-type) used in order to protect the HOBO data logger was found to provide the best protection against the effects of solar radiation on measurements of temperature and relative humidity. The precision and accuracy of a device that measures temperature and relative humidity depend on an efficient shelter that minimizes the interference caused by solar radiation, thereby avoiding erroneous analysis of the data obtained.
Validation of triaxial accelerometers to measure the lying behaviour of adult domestic horses.
DuBois, C; Zakrajsek, E; Haley, D B; Merkies, K
2015-01-01
Examining the characteristics of an animal's lying behaviour, such as frequency and duration of lying bouts, has become increasingly relevant for animal welfare research. Triaxial accelerometers have the advantage of being able to continuously monitor an animal's standing and lying behaviour without relying on live observations or video recordings. Multiple models of accelerometers have been validated for use in monitoring dairy cattle; however, no units have been validated for use in equines. This study tested Onset Pendant G data loggers attached to the hind limb of each of two mature Standardbred horses for a period of 5 days. Data loggers were set to record their position every 20 s. Horses were monitored via live observations during the day and by video recordings during the night to compare activity against accelerometer data. All lying events occurred overnight (three to five lying bouts per horse per night). Data collected from the loggers was converted and edited using a macro program to calculate the number of bouts and the length of time each animal spent lying down by hour and by day. A paired t-test showed no significant difference between the video observations and the output from the data loggers (P=0.301). The data loggers did not distinguish standing hipshot from standing square. Predictability, sensitivity, and specificity were all >99%. This study has validated the use of Onset Pendant G data loggers to determine the frequency and duration of standing and lying bouts in adult horses when set to sample and register readings at 20 s intervals.
Thermally driven self-healing using copper nanofiber heater
NASA Astrophysics Data System (ADS)
Lee, Min Wook; Jo, Hong Seok; Yoon, Sam S.; Yarin, Alexander L.
2017-07-01
Nano-textured transparent heaters made of copper nanofibers (CuNFs) are used to facilitate accelerated self-healing of bromobutyl rubber (BIIR). The heater and BIIR layer are separately deposited on each side of a transparent flexible polyethylene terephthalate (PET) substrate. A pre-notched crack on the BIIR layer was bridged due to heating facilitated by CuNFs. In the corrosion test, a cracked BIIR layer covered a steel substrate. An accelerated self-healing of the crack due to the transparent copper nanofiber heater facilitated an anti-corrosion protective effect of the BIIR layer.
Evaluating the effectiveness of a logger safety training program.
Bell, Jennifer L; Grushecky, Shawn T
2006-01-01
Logger safety training programs are rarely, if ever, evaluated as to their effectiveness in reducing injuries. Workers' compensation claim rates were used to evaluate the effectiveness of a logger safety training program, the West Virginia Loggers' Safety Initiative (LSI). There was no claim rate decline detected in the majority (67%) of companies that participated in all 4 years of the LSI. Furthermore, their rate did not differ from the rest of the WV logging industry that did not participate in the LSI. Worker turnover was significantly related to claim rates; companies with higher turnover of employees had higher claim rates. Companies using feller bunchers to harvest trees at least part of the time had a significantly lower claim rate than companies not using them. Companies that had more inspections per year had lower claim rates. High injury rates persist even in companies that receive safety training; high employee turnover may affect the efficacy of training programs. The logging industry should be encouraged to facilitate the mechanization of logging tasks, to address barriers to employee retention, and to increase the number of in-the-field performance monitoring inspections. Impact on industry There are many states whose logger safety programs include only about 4-8 hours of safe work practices training. These states may look to West Virginia's expanded training program (the LSI) as a model for their own programs. However, the LSI training may not be reaching loggers due to the delay in administering training to new employees and high levels of employee turnover. Regardless of training status, loggers' claim rates decline significantly the longer they work for a company. It may be that high injury rates in the state of West Virginia would be best addressed by finding ways to encourage and facilitate companies to become more mechanized in their harvesting practices, and to increase employee tenure. Increasing the number of yearly performance inspections may also be a venue to reduce claim rates. Future research could investigate in better detail the working conditions of West Virginia loggers and identify barriers to job tenure, particularly for workers whose primary job task is chainsaw operation. A larger-scale study of the effect of performance monitoring inspections on claim rates is also warranted.
Characterization of Stress Corrosion Cracking Using Laser Ultrasonics
DOT National Transportation Integrated Search
2008-08-31
In-service inspection of gas and oil pipelines is a subject of great current interest. Issues of safety and fitness for service have driven extensive efforts to develop effective monitoring and inspection techniques. A number of effective NDT techniq...
Galvanic Corrosion of Lead by Iron (Oxyhydr)Oxides: Potential Impacts on Drinking Water Quality.
Trueman, Benjamin F; Sweet, Gregory A; Harding, Matthew D; Estabrook, Hayden; Bishop, D Paul; Gagnon, Graham A
2017-06-20
Lead exposure via drinking water remains a significant public health risk; this study explored the potential effects of upstream iron corrosion on lead mobility in water distribution systems. Specifically, galvanic corrosion of lead by iron (oxyhydr)oxides was investigated. Coupling an iron mineral cathode with metallic lead in a galvanic cell increased lead release by 531 μg L -1 on average-a 9-fold increase over uniform corrosion in the absence of iron. Cathodes were composed of spark plasma sintered Fe 3 O 4 or α-Fe 2 O 3 or field-extracted Fe 3 O 4 and α-FeOOH. Orthophosphate immobilized oxidized lead as insoluble hydroxypyromorphite, while humic acid enhanced lead mobility. Addition of a humic isolate increased lead release due to uniform corrosion by 81 μg L -1 and-upon coupling lead to a mineral cathode-release due to galvanic corrosion by 990 μg L -1 . Elevated lead in the presence of humic acid appeared to be driven by complexation, with 208 Pb and UV 254 size-exclusion chromatograms exhibiting strong correlation under these conditions (R 2 average = 0.87). A significant iron corrosion effect was consistent with field data: lead levels after lead service line replacement were greater by factors of 2.3-4.7 at sites supplied by unlined cast iron distribution mains compared with the alternative, lined ductile iron.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-07
... purchase of three hundred acoustic leak detection sensors/loggers (``loggers'') and one fully programmable... and one programmable radio transceiver (Model: Gutermann Zonescan 820) on the basis that there are no...
AcquiControl: Seismic Data Logger Control via iPhone
NASA Astrophysics Data System (ADS)
Golden, S.; Horkley, B.
2010-12-01
Seismic stations are often placed in remote areas, accessible only a few times per year. A typical stand-alone seismic station consists of the seismometer and a data logger, which records the data to attached disk drives or flash memory for later collection by a field crew. Even if the station uses telemetry, maintenance visits may be minimized but rarely entirely avoided. During station visits, field personnel use laptops or handheld devices to control the data logger and seismometer, check their status, and adjust their configuration if necessary. The efficiency and reliability of these on-site quality control tasks has a significant impact on the overall performance of seismic field operations. One widespread seismic data logger is the RT130 by REFTEK Inc., which is traditionally controlled through REFTEK proprietary software designed to run on Palm compatible devices. While this software functions well, compatible Palm handhelds went out of production and are getting hard to find. Also we felt, that its user interface still offered room for improvement. Therefore, we developed a new RT130 control application, named AcquiControl, which runs on Apple’s iPhone or iPod Touch, and features a redesigned, user-friendly interface. The Palm handheld communicates with the data logger through a serial cable. While this is technically also possible with the iPhone or iPod Touch, the production and licensing costs for the required custom cable so far kept us from further pursuing this path. Instead, AcquiControl makes use of the wireless networking capabilities inherent to any iPhone or iPod Touch. To wirelessly connect to an RT130 data logger, we use a wireless-to-serial “dongle” manufactured by Serialio.com, which attaches directly to the data logger’s serial port. First experiments with this setup have shown, that it is actually more convenient to use than a directly attached serial cable, especially during less than ideal environmental conditions such as present while working in the rain. AcquiControl offers a third-party alternative to interface with RT130 data loggers in the field. Currently it covers most frequently used capabilities of the older Palm software through equivalent features, with plans to add more as needed. Beyond that, the application could be easily adapted to support other data loggers than the RT130, possibly even by other manufacturers. This would give users a more uniform interface regardless of data logger model, which could become an advantage during mixed-equipment campaigns. Also, the same software could be expanded to allow the direct input of various field notes, which could be downloaded together with automatically logged configuration data to ease the preparation of seismic metadata or the building of a project-central seismic database.
Electrokinetic nanoparticle treatment for corrosion remediation on simulated reinforced bridge deck
NASA Astrophysics Data System (ADS)
Kupwade-Patil, Kunal; Cardenas, Henry E.
2013-09-01
ASTM G109 specimens were used in this work as these simulate the configuration of the bridge deck and subjected to elevated chloride levels. Nanoparticles which were 24 nm in size were driven directly through the concrete matrix and to the reinforcement using an electric field. The intent was to use the nanoparticles as pore blocking agents that could prevent chlorides from re-entering and accessing the rebar. Electrochemical, microstructure, and pore structure characterization was conducted on the electrokinetic nanoparticle (EN) treated and control specimens. At the end of post saltwater exposure period EN-treated specimens exhibited lower corrosion current densities, chloride contents below the threshold limit for new construction and 22 % reduction in porosity as compared to the controls. EN treatment was successful in mitigating reinforcement corrosion in concrete.
γ-radiation induced corrosion of copper in bentonite-water systems under anaerobic conditions
NASA Astrophysics Data System (ADS)
Karin Norrfors, K.; Björkbacka, Åsa; Kessler, Amanda; Wold, Susanna; Jonsson, Mats
2018-03-01
In this work we have experimentally studied the impact of bentonite clay on the process of radiation-induced copper corrosion in anoxic water. The motivation for this is to further develop our understanding of radiation-driven processes occurring in deep geological repositories for spent nuclear fuel where copper canisters containing the spent nuclear fuel will be embedded in compacted bentonite. Experiments on radiation-induced corrosion in the presence and absence of bentonite were performed along with experiments elucidating the impact irradiation on the Cu2+ adsorption capacity of bentonite. The experiments presented in this work show that the presence of bentonite clay has no or very little effect on the magnitude of radiation-induced corrosion of copper in anoxic aqueous systems. The absence of a protective effect similar to that observed for radiation-induced dissolution of UO2 is attributed to differences in the corrosion mechanism. This provides further support for the previously proposed mechanism where the hydroxyl radical is the key radiolytic oxidant responsible for the corrosion of copper. The radiation effect on the bentonite sorption capacity of Cu2+ (reduced capacity) is in line with what has previously been reported for other cations. The reduced cation sorption capacity is partly attributed to a loss of Al-OH sites upon irradiation.
Li, Jian; Kang, Ruimei; Tang, Xiaohua; She, Houde; Yang, Yaoxia; Zha, Fei
2016-04-14
Oil-polluted water has become a worldwide problem due to increasing industrial oily wastewater as well as frequent oil-spill pollution. Compared with underwater superoleophobic (water-removing) filtration membranes, superhydrophobic/superoleophilic (oil-removing) materials have advantages as they can be used for the filtration of heavy oil or the absorption of floating oil from water/oil mixtures. However, most of the superhydrophobic materials used for oil/water separation lose their superhydrophobicity when exposed to hot (e.g. >50 °C) water and strong corrosive liquids. Herein, we demonstrate superhydrophobic overlapped candle soot (CS) and silica coated meshes that can repel hot water (about 92 °C) and strong corrosive liquids, and were used for the gravity driven separation of oil-water mixtures in hot water and strong acidic, alkaline, and salty environments. To the best of our knowledge, we are unaware of any previously reported studies on the use of superhydrophobic materials for the separation of oil from hot water and corrosive aqueous media. In addition, the as-prepared robust superhydrophobic CS and silica coated meshes can separate a series of oils and organic solvents like kerosene, toluene, petroleum ether, heptane and chloroform from water with a separation efficiency larger than 99.0%. Moreover, the as-prepared coated mesh still maintained a separation efficiency above 98.5% and stable recyclability after 55 cycles of separation. The robust superhydrophobic meshes developed in this work can therefore be practically used as a highly efficient filtration membrane for the separation of oil from harsh water conditions, benefiting the environment and human health.
A novel design for sap flux data acquisition in large research plots using open source components
NASA Astrophysics Data System (ADS)
Hawthorne, D. A.; Oishi, A. C.
2017-12-01
Sap flux sensors are a widely-used tool for estimating in-situ, tree-level transpiration rates. These probes are installed in the stems of multiple trees within a study area and are typically left in place throughout the year. Sensors vary in their design and theory of operation, but all require electrical power for a heating element and produce at least one analog signal that must be digitized for storage. There are two topologies traditionally adopted to energize these sensors and gather the data from them. In one, a single data logger and power source are used. Dedicated cables radiate out from the logger to supply power to each of the probes and retrieve analog signals. In the other layout, a standalone data logger is located at each monitored tree. Batteries must then be distributed throughout the plot to service these loggers. We present a hybrid solution based on industrial control systems that employs a central data logger and battery, but co-locates digitizing hardware with the sensors at each tree. Each hardware node is able to communicate and share power over wire links with neighboring nodes. The resulting network provides a fault-tolerant path between the logger and each sensor. The approach is optimized to limit disturbance of the study plot, protect signal integrity and to enhance system reliability. This open-source implementation is built on the Arduino micro-controller system and employs RS485 and Modbus communications protocols. It is supported by laptop based management software coded in Python. The system is designed to be readily fabricated and programmed by non-experts. It works with a variety of sap-flux measurement techniques and it is able to interface to additional environmental sensors.
Atheull, Adolphe Nfotabong; Din, Ndongo; Longonje, Simon N; Koedam, Nico; Dahdouh-Guebas, Farid
2009-11-17
Worldwide there is growing research interest in the ethnobiology of mangrove forests. Notwithstanding that, little information has been published about ethnobiology of mangrove forests in Cameroon. The aims of this study were a) to analyze the harvesting methods and the local selling of mangrove wood products by loggers in the vicinity of Wouri estuary and b) to investigate the patterns of subsistence uses of mangrove wood products around the Douala-Edea reserve. Semi-structured interviews were conducted with 120 active mangrove loggers in 23 Douala wood markets and 103 households located in three villages (Mbiako, Yoyo I and Yoyo II) close to Douala-Edea reserve. In each of the three densely populated villages, every second household was chosen for sampling while in all markets, mangrove loggers were chosen randomly. In addition, log diameters were measured in each market using a wooden foldable tape measure. A post hoc analysis (Newman-Keuls test) was performed in order to detect the common wood class diameter sold in the Douala wood markets. The analysis of the loggers' survey data has shown that large logs of Rhizophora with diameter greater than 40 cm were common in the Douala wood markets and were more closely associated with loggers who used chainsaws. In addition to the general mangroves wood products selling, the analysis on a subsistence level (households' survey) suggests the local population's dependence on mangroves, with multiple uses of Rhizophora racemosa Meyer, R. harrisonii Leechman, Avicennia germinans L. Stearn., Laguncularia racemosa Gaertn. f. and Conocarpus erectus L. timbers for furniture, fences, smoking fish, and fuelwood. Finally, Nypa fruticans (Thunb.) Wurmb. leaves were used as thatching material for house walls and roofs. Our findings revealed that big logs of Rhizophora were commonly sold by the loggers. A majority of loggers (60%) reported that mangrove marketed wood constitute a principal source of income. Most of the villagers (85.83%) often depend on mangroves for subsistence needs and for them there is no substitute for mangrove wood. Therefore, more efforts should be undertaken at the national level to implement conservation, management and sustainable use of these coastal forests.
2009-01-01
Background Worldwide there is growing research interest in the ethnobiology of mangrove forests. Notwithstanding that, little information has been published about ethnobiology of mangrove forests in Cameroon. The aims of this study were a) to analyze the harvesting methods and the local selling of mangrove wood products by loggers in the vicinity of Wouri estuary and b) to investigate the patterns of subsistence uses of mangrove wood products around the Douala-Edea reserve. Methods Semi-structured interviews were conducted with 120 active mangrove loggers in 23 Douala wood markets and 103 households located in three villages (Mbiako, Yoyo I and Yoyo II) close to Douala-Edea reserve. In each of the three densely populated villages, every second household was chosen for sampling while in all markets, mangrove loggers were chosen randomly. In addition, log diameters were measured in each market using a wooden foldable tape measure. A post hoc analysis (Newman-Keuls test) was performed in order to detect the common wood class diameter sold in the Douala wood markets. Results The analysis of the loggers' survey data has shown that large logs of Rhizophora with diameter greater than 40 cm were common in the Douala wood markets and were more closely associated with loggers who used chainsaws. In addition to the general mangroves wood products selling, the analysis on a subsistence level (households' survey) suggests the local population's dependence on mangroves, with multiple uses of Rhizophora racemosa Meyer, R. harrisonii Leechman, Avicennia germinans L. Stearn., Laguncularia racemosa Gaertn. f. and Conocarpus erectus L. timbers for furniture, fences, smoking fish, and fuelwood. Finally, Nypa fruticans (Thunb.) Wurmb. leaves were used as thatching material for house walls and roofs. Conclusion Our findings revealed that big logs of Rhizophora were commonly sold by the loggers. A majority of loggers (60%) reported that mangrove marketed wood constitute a principal source of income. Most of the villagers (85.83%) often depend on mangroves for subsistence needs and for them there is no substitute for mangrove wood. Therefore, more efforts should be undertaken at the national level to implement conservation, management and sustainable use of these coastal forests. PMID:19919680
A Parametric Oscillator Experiment for Undergraduates
NASA Astrophysics Data System (ADS)
Huff, Alison; Thompson, Johnathon; Pate, Jacob; Kim, Hannah; Chiao, Raymond; Sharping, Jay
We describe an upper-division undergraduate-level analytic mechanics experiment or classroom demonstration of a weakly-damped pendulum driven into parametric resonance. Students can derive the equations of motion from first principles and extract key oscillator features, such as quality factor and parametric gain, from experimental data. The apparatus is compact, portable and easily constructed from inexpensive components. Motion control and data acquisition are accomplished using an Arduino micro-controller incorporating a servo motor, laser sensor, and data logger. We record the passage time of the pendulum through its equilibrium position and obtain the maximum speed per oscillation as a function of time. As examples of the interesting physics which the experiment reveals, we present contour plots depicting the energy of the system as functions of driven frequency and modulation depth. We observe the transition to steady state oscillation and compare the experimental oscillation threshold with theoretical expectations. A thorough understanding of this hands-on laboratory exercise provides a foundation for current research in quantum information and opto-mechanics, where damped harmonic motion, quality factor, and parametric amplification are central.
High temperature corrosion of cold worked YUS409D bellows of bellow-sealed valve in LBE
NASA Astrophysics Data System (ADS)
Mustari1, A. P. A.; Irwanto1, D.; Takahashi, M.
2017-01-01
Lead-bismuth eutectic (LBE) loop test is highly contributes to the lead-alloy-cooled fast breeder reactor (LFR) and accelerator driven system (ADS) research and development by providing comprehensive results of both corrosion and erosion phenomenon. Bellows-sealed valve is a crucial part in the LBE loop test apparatus, due to its capability of preventing corrosion on valve spring, thus improves the operation time of the system. LBE is very corrosive to stainless steel by formation of oxide layer or elemental dissolution, e.g. Ni. Thus, new type of bellows for bellows-sealed valve made of nickel free material, i.e. YUS409D, is proposed to be used in the LBE. Bellows material undergo heat treatments for mechanical improvement including cold working and annealing. The thickness reduction by the heat treatments is about 90% of initial condition. Corrosion behavior of the bellows has been studied in stagnant LBE at 500 and 600 °C for 500 hours. The oxygen concentration was controlled at about 10-7 wt%. Typical oxide layers were developed on the surface. Oxidation rate was sharply increased at 600°C.
NASA Technical Reports Server (NTRS)
Jovic, Srboljub
2015-01-01
This document provides the software design description for the two core software components, the LVC Gateway, the LVC Gateway Toolbox, and two participants, the LVC Gateway Data Logger and the SAA Processor (SaaProc).
Krawczel, P D; Klaiber, L M; Thibeau, S S; Dann, H M
2012-08-01
Assessing feeding behavior is important in understanding the effects of nutrition and management on the well-being of dairy cows. Historically, collection of these data from cows fed with a Calan Broadbent Feeding System (American Calan Inc., Northwood, NH) required the labor-intensive practices of direct observation or video review. The objective of this study was to evaluate the agreement between the output of a HOBO change-of-state data logger (Onset Computer Corp., Bourne, MA), mounted to the door shell and latch plate, and video data summarized with continuous sampling. Data (number of feed bin visits per day and feeding time in minutes per day) were recorded with both methods from 26 lactating cows and 10 nonlactating cows for 3 d per cow (n=108). The agreement of the data logger and video methods was evaluated using the REG procedure of SAS to compare the mean response of the methods against the difference between the methods. The maximum allowable difference (MAD) was set at ±3 for bin visits and ±20 min for feeding time. Ranges for feed bin visits (2 to 140 per d) and feeding time (28 to 267 min/d) were established from video data. Using the complete data set, agreement was partially established between the data logger and video methods for feed bin visits, but not established for feeding time. The complete data set generated by the data logger was screened to remove visits of a duration ≤3 s, reflecting a cow unable to enter a feed bin (representing 7% of all data) and ≥5,400 s, reflecting a failure of the data logger to align properly with its corresponding magnetic field (representing <1% of all data). Using the resulting screened data set, agreement was established for feed bin visits and feeding time. For bin visits, 4% of the data was beyond the MAD. For feeding time, 3% of the data was beyond the MAD and 74% of the data was ±1 min. The insignificant P-value, low coefficient of determination, and concentration of the data within the MAD indicate the agreement of the change-of-state data logger and video data. This suggests the usage of a change-of-state data logger to assess the feeding behavior of cows feeding from a Calan Broadbent Feeding System is appropriate. Use of the screening criteria for data analysis is recommended. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Clinicians’ and researchers’ perspectives on manual wheelchair data loggers
Routhier, François; Lettre, Josiane; Miller, William C.; Borisoff, Jaimie F.; Keetch, Kate; Mitchell, Ian M.
2017-01-01
Recent studies have employed data loggers to record a wide range of, sometimes differing, objective outcomes associated with the use of manual wheelchairs. To identify which outcomes are broadly perceived to be the most important to measure when objectively documenting manual wheelchair use, a cross-sectional survey was conducted with groups of researchers and clinicians in the field of wheeled mobility. We also surveyed the challenges these groups experienced when using data loggers. The survey was informed by a previous scoping review of the scientific and gray literature. Seventy-four people, with various academic and professional backgrounds, completed the survey: 57 researchers (77.0%) and 17 clinicians (23.0%). Regarding the importance they attributed to commonly measured outcomes, the most highly rated outcome identified by both groups was “distance traveled.” There were significant differences between the groups’ perspectives in rating and ranking the importance of “pressure-relief activities”, “seat pressure” and “acceleration.” In terms of challenges or barriers associated with the use of data loggers for monitoring manual wheelchair use, it appears that researchers and clinicians have relatively similar needs and preferences. However, only clinicians reported that the time they wanted to, or could, allocate to review recorded information was a potential hardship. Our hope is that these results will help further development and increase the functionality and applicability of data loggers for manual wheelchairs in research and clinical contexts. PMID:28202382
Niphargus: a silicon band-gap sensor temperature logger for high-precision environmental monitoring
NASA Astrophysics Data System (ADS)
Burlet, Christian; Vanbrabant, Yves; Piessens, Kris; Welkenhuysen, Kris; Verheyden, Sophie
2014-05-01
A temperature logger, called 'Niphargus', was developed at the Geological Survey of Belgium to monitor temperature of local natural processes with sensitivity of the order of a few hundredths of degrees to monitor temperature variability in open air, caves, soils and rivers. The newly developed instrument uses a state-of-the-art band-gap silicon temperature sensor with digital output. This sensor reduces the risk of drift associated with thermistor-based sensing devices, especially in humid environments. The Niphargus is designed to be highly reliable, low-cost and powered by a single lithium cell with up to several years autonomy depending on the sampling rate and environmental conditions. The Niphargus was evaluated in an ice point bath experiment in terms of temperature accuracy and thermal inertia. The small size and low power consumption of the logger allow its use in difficult accessible environments, e.g. caves and space-constrained applications, inside a rock in a water stream. In both cases, the loggers have proven to be reliable and accurate devices. For example, spectral analysis of the temperature signal in the Han caves (Belgium) allowed detection and isolation of a 0.005° C amplitude day-night periodic signal in the temperature curve. PIC Figure 1: a Niphargus logger in its standard size. SMD components side. Photo credit: W. Miseur
UO(2) Oxidative Corrosion by Nonclassical Diffusion.
Stubbs, Joanne E; Chaka, Anne M; Ilton, Eugene S; Biwer, Craig A; Engelhard, Mark H; Bargar, John R; Eng, Peter J
2015-06-19
Using x-ray scattering, spectroscopy, and density-functional theory, we determine the structure of the oxidation front when a UO(2) (111) surface is exposed to oxygen at ambient conditions. In contrast to classical diffusion and previously reported bulk UO(2+x) structures, we find oxygen interstitials order into a nanoscale superlattice with three-layer periodicity and uranium in three oxidation states: IV, V, and VI. This oscillatory diffusion profile is driven by the nature of the electron transfer process, and has implications for understanding the initial stages of oxidative corrosion in materials at the atomistic level.
Loggers' Views on Training After Attending a Three-Day Educational Program.
ERIC Educational Resources Information Center
Reeb, James E.
1996-01-01
Surveyed 120 loggers who attended a 3-day educational program on first aid and adult cardiopulmonary resuscitation, forest ecology and silviculture, woods safety, and small business management. Results indicate that the training was worthwhile to the participants and they would be willing to attend additional training. (JRH)
Turbidity threshold sampling for suspended sediment load estimation
Jack Lewis; Rand Eads
2001-01-01
Abstract - The paper discusses an automated procedure for measuring turbidity and sampling suspended sediment. The basic equipment consists of a programmable data logger, an in situ turbidimeter, a pumping sampler, and a stage-measuring device. The data logger program employs turbidity to govern sample collection during each transport event. Mounting configurations and...
Characteristics of West Virginia loggers during economically difficult times
Ben Spong; Jinxing Wang; David Summerfield
2011-01-01
West Virginia licensed loggers have been surveyed over the years regarding their business, operational, and personal characteristics. An update of this study was completed in 2009 to illustrate the impacts of the current economic conditions on the forestry and forest products industries. Additionally, this survey will help demonstrate the preparedness of the logging...
A portable system for characterizing wildland fire behavior
Bret Butler; D. Jimenez; J. Forthofer; K. Shannon; Paul Sopko
2010-01-01
A field deployable system for quantifying energy and mass transport in wildland fires is described. The system consists of two enclosures: The first is a sensor/data logger combination package that allows characterization of convective/radiant energy transport in fires. This package contains batteries, a programmable data logger, sensors, and other electronics. The...
Kartoğlu, Umit; Nelaj, Erida; Maire, Denis
2010-05-28
This intervention study was conducted in Albania to establish the superiority of the Fridge-tag (30-day electronic refrigerator temperature logger) against thermometers. Intervention sites used Fridge-tag and a modified temperature control record sheet, while control sites continued with their routine operation with thermometers. All refrigerators in both groups were equipped with downloadable electronic data loggers to record temperatures for reference. Focus group sessions were conducted with involved staff to discuss temperature monitoring, Fridge-tag use and its user-friendliness. Significant discrepancies were observed between thermometer readings and the electronic data loggers in control sites, while all alarms from Fridge-tag were confirmed in the intervention group. Thermometers are not sufficient to monitor temperatures in refrigerators since they miss the great majority of low and high alarms. Fridge-tag has proven to be an effective tool in providing health workers with the information they need to take the necessary actions when there are refrigerator temperature variations. (c) 2010 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Rao, Amar P.
The Davis-Schrimpf Seep Field is a cluster of about 50 transtension-related geothermal seeps in the Imperial Valley, southeastern California. Five temperature time-series were collected from four features and compared to one another, against prior time-series, and to local seismicity. Loggers placed in separate vents within one seep returned moderate anti-correlation. Vents may selectively clog and unclog. Clogging frequencies explaining the observed level of negative correlation were given. Loggers placed in the same vent produced 87-92% positive correlation. It is therefore likely that the vast majority of temperature data measured with loggers possesses meaningful accuracy. Loggers placed in separate seeps exhibited correlation close to or greater than the statistically significant 60% threshold. I propose two lineaments provide a hydraulic connection between these seeps. Two Mw>3.0 earthquake swarms, including one Mw>4.0 event, within 24 kilometers showed possible linkage with >5 degree Celsius temperature perturbations. Seepage warmed 14.5-36.8 degrees Celsius over 5-7 years.
Clinicians' and Researchers' Perspectives on Manual Wheelchair Data Loggers.
Routhier, François; Lettre, Josiane; Miller, William C; Borisoff, Jaimie F; Keetch, Kate; Mitchell, Ian M
2017-07-01
Recent studies have used data loggers to record a wide range of, sometimes differing, objective outcomes associated with the use of manual wheelchairs. To identify which outcomes are broadly perceived to be the most important to measure when objectively documenting manual wheelchair use, a cross-sectional survey was conducted with groups of researchers and clinicians in the field of wheeled mobility. We also surveyed the challenges these groups experienced when using data loggers. The survey was informed by a previous scoping review of the scientific and gray literature. Seventy-four people with various academic and professional backgrounds completed the survey: 57 researchers (77.0%) and 17 clinicians (23.0%). Regarding the importance they attributed to commonly measured outcomes, the most highly rated outcome identified by both groups was "distance traveled." There were significant differences between the groups' perspectives in rating and ranking the importance of "pressure-relief activities," "seat pressure," and "acceleration." In terms of challenges or barriers associated with the use of data loggers for monitoring manual wheelchair use, it appears that researchers and clinicians have relatively similar needs and preferences. However, only clinicians reported that the time they wanted to, or could, allocate to review recorded information was a potential hardship. Our hope is that these results will help further development and increase the functionality and applicability of data loggers for manual wheelchairs in research and clinical contexts. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Xu, Jiang; Ma, Jin Jin; Munroe, Paul; Xie, Zong-Han
The development of new corrosion-resistant coatings is often challenging, but strongly driven by the potential benefits such coatings hold. A nanostructured Ta2N coating was deposited on a Ti-6Al-4V substrate in an Ar-N atmosphere using a double cathode glow discharge plasma method with the aim being to improve its corrosion resistance in oral environments. The microstructure of the coating was investigated by a range of methods including XRD, SEM-EDS and TEM. The as-deposited coating exhibited densely packed fibrous structure and the individual fibers were composed of equiaxed grains with an average grain size ˜13nm, arranged along the longitudinal axis of the individual fibers. The electrochemical behavior of the Ta2N nanocrystalline coating was characterized in artificial saliva containing different NaF concentrations by a range of electrochemical techniques, including potentiodynamic measurement, EIS, capacitance and PZFC measurements. It was shown that the coating possessed superior corrosion resistance compared to uncoated Ti-6Al-4V, because its passive film exhibited higher stability against the fluoride ion attack.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pu, Chao; Gao, Yanfei; Wang, Yanli
To study the stress corrosion intergranular cracking mechanism, a diffusion-coupled cohesive zone model (CZM) is proposed for the simulation of the stress-assisted diffusional process along grain boundaries and the mechanical response of grain boundary sliding and separation. This simulation methodology considers the synergistic effects of impurity diffusion driven by pressure gradient and degradation of grain boundary strength by impurity concentration. The diffusion-coupled CZM is combined with crystal plasticity finite element model (CPFEM) to simulate intergranular fracture of polycrystalline material under corrosive environment. Significant heterogeneity of the stress field and extensive impurity accumulation is observed at grain boundaries and junction points.more » Deformation mechanism maps are constructed with respect to the grain boundary degradation factor and applied strain rate, which dictate the transition from internal to near-surface intergranular fracture modes under various strain amplitudes and grain sizes.« less
NASA Technical Reports Server (NTRS)
Rosner, Daniel E.; Nagarajan, R.
1987-01-01
An analysis is undertaken of aerodynamically- and centrifugally-driven liquid condensate layers on nonisothermal combustion turbines' stator vanes and rotor blades. Attention is given to the quantitative consequences of one possible mechanism for the initiation of 'hot corrosion' in the underlying blade material through a 'fluxing' of the protective oxide coating by the molten salt of the Newtonian condensate film. Illustrative calculations are presented for the condensate streamline pattern and the distributions of the steady-state condensate layer thickness, together with the corresponding oxide dissolution rate, for a test turbine blade.
46 CFR 169.675 - Generators and motors.
Code of Federal Regulations, 2011 CFR
2011-10-01
... with a nameplate of corrosion-resistant material marked with the following information as applicable... having only electrically driven fire and bilge pumps must have two generators. One of these generators... at the lowest part of the frame for attaching a drain pipe or drain plug. (f) Except as provided in...
Jet Engines as High-Capacity Vacuum Pumps
NASA Technical Reports Server (NTRS)
Wojciechowski, C. J.
1983-01-01
Large diffuser operations envelope and long run times possible. Jet engine driven ejector/diffuser system combines two turbojet engines and variable-area-ratio ejector in two stages. Applications in such industrial proesses as handling corrosive fumes, evaporation of milk and fruit juices, petroleum distillation, and dehydration of blood plasma and penicillin.
Working safely in summertime heat
Robert B. Rummer
1997-01-01
As logging operations continue in the hotter months of he year, the safety hazard of heat stress appears. Loggers are particularly at risk, because the combination of hard physical work and outdoor conditions puts high demands on the body. While loggers rarely die from heat stress, they may suffer heat illness symptoms ranging from the discomfort of heat rash to nausea...
The Role of Communicative Feedback in Successful Water Conservation Programs
ERIC Educational Resources Information Center
Tom, Gail; Tauchus, Gail; Williams, Jared; Tong, Stephanie
2011-01-01
The Sacramento County Water Agency has made available 2 water conservation programs to its customers. The Data Logger Program attaches the Meter Master Model 100 EL data logger to the customer's water meter for 1 week and provides a detailed report of water usage from each fixture. The Water Wise House Call Program provides findings and…
ERIC Educational Resources Information Center
Tosa, Sachiko; Martin, Fred
2010-01-01
This study examined how a professional development program which incorporates the use of electronic data-loggers could impact on science teachers' attitudes towards inquiry-based teaching. The participants were 28 science or technology teachers who attended workshops offered in the United States and Japan. The professional development program…
Production and Costs of the Chambers Delimbinator in First Thinning of Pine Plantations
Scott T. Mooney; Kevin D. Boston; W. Dale Greene
2000-01-01
Production and quality measures were collected and analyzed for a new chain-flail delimbing machine, Chambers Delimbinator, on two operations in central and southwestern Georgia. The first operation, Logger A, used two skidders and one loader while the second operation, Logger B, used two skidder and two loaders. Lobber B with the lower cycle time and larger piece...
Potential for shared log transport services
Tim McDonald; Steve Taylor; Jorge Valenzuela
2001-01-01
A simulation model of a log transport logistics network was developed. The model could be structured to either share truck capacity among a group of loggers, or to assign a fixed number of trucks to individual loggers. Another variation of the model allowed the use of a staging yard to set out loaded trailers and deliver them to destinations using dedicated shuttle...
An inexpensive and reliable monitoring station design for use with lightweight, compact data loggers
Ronald S., Jr. Zalesny; Adam H. Wiese; Edmund O. Bauer; William L., Jr. Headlee; Richard B. Hall; A. Assibi Mahama; Jill A. Zalesny
2007-01-01
We designed, constructed, and field-tested an inexpensive and reliable monitoring station that can be used with lightweight, compact data loggers. We feel this design, improved three times over 6 yr, could benefit anyone in nursery or field settings interested in acquiring environmental data. We provide step-by-step instructions on the construction of the monitoring...
Candidate molten salt investigation for an accelerator driven subcritical core
NASA Astrophysics Data System (ADS)
Sooby, E.; Baty, A.; Beneš, O.; McIntyre, P.; Pogue, N.; Salanne, M.; Sattarov, A.
2013-09-01
We report a design for accelerator-driven subcritical fission in a molten salt core (ADSMS) that utilizes a fuel salt composed of NaCl and transuranic (TRU) chlorides. The ADSMS core is designed for fast neutronics (28% of neutrons >1 MeV) to optimize TRU destruction. The choice of a NaCl-based salt offers benefits for corrosion, operating temperature, and actinide solubility as compared with LiF-based fuel salts. A molecular dynamics (MD) code has been used to estimate properties of the molten salt system which are important for ADSMS design but have never been measured experimentally. Results from the MD studies are reported. Experimental measurements of fuel salt properties and studies of corrosion and radiation damage on candidate metals for the core vessel are anticipated. A special thanks is due to Prof. Paul Madden for introducing the ADSMS group to the concept of using the molten salt as the spallation target, rather than a conventional heavy metal spallation target. This feature helps to optimize this core as a Pu/TRU burner.
A new data logger for integrated geophysical monitoring
NASA Astrophysics Data System (ADS)
Orazi, Massimo; Peluso, Rosario; Caputo, Antonio; Giudicepietro, Flora; Martini, Marcello
2015-04-01
GILDA digital recorder is a data logger developed at Osservatorio Vesuviano (INGV). It provides excellent data quality with low power consumption and low production cost. It is widely used in the multi-parametric monitoring networks of Neapolitan volcanoes and Stromboli volcano. We have improved the characteristics of GILDA recorder to realize a robust user-oriented acquisition system for integrated geophysical monitoring. We have designed and implemented new capabilities concerning the use of the low rate channels to get data of environmental parameters of the station. We also improved the stand-alone version of the data logger. This version can be particularly useful for scientific experiments and to rapidly upgrade permanent monitoring networks. Furthermore, the local storage can be used as back-up for the monitoring systems in continuous transmission, in case of failure of the transmission system. Some firmware changes have been made in order to improve the performance of the instrument. In particular, the low rate acquisition channels were conditioned to acquire internal parameters of the recorder such as the temperature and voltage. A prototype of the new version of the logger is currently installed at Campi Flegrei for a experimental application. Our experiment is aimed at testing the new version of GILDA data logger in multi-board configuration for multiparametric acquisitions. A second objective of the experiment is the comparison of the recorded data with geochemical data acquired by a multiparametric geochemical station to investigate possible correlations between seismic and geochemical parameters. The target site of the experiment is "Bocca Grande" fumarole in Solfatara volcano. By exploiting the modularity of GILDA, for the experiment has been realized an acquisition system based on three dataloggers for a total of 12 available channels. One of GILDA recorders is the Master and the other two are Slaves. The Master is responsible for the initial configuration of the GPS receiver for timing data. The two data loggers configured in slave mode await the end of the initial configuration and then receive the GPS timing data and PPS from the Master. This allows you to use one GPS receiver and optimize power consumption. The whole system is configured to continuously transmit data via WiFi and to locally store data.
Forin-Wiart, Marie-Amélie; Hubert, Pauline; Sirguey, Pascal; Poulle, Marie-Lazarine
2015-01-01
Recently developed low-cost Global Positioning System (GPS) data loggers are promising tools for wildlife research because of their affordability for low-budget projects and ability to simultaneously track a greater number of individuals compared with expensive built-in wildlife GPS. However, the reliability of these devices must be carefully examined because they were not developed to track wildlife. This study aimed to assess the performance and accuracy of commercially available GPS data loggers for the first time using the same methods applied to test built-in wildlife GPS. The effects of antenna position, fix interval and habitat on the fix-success rate (FSR) and location error (LE) of CatLog data loggers were investigated in stationary tests, whereas the effects of animal movements on these errors were investigated in motion tests. The units operated well and presented consistent performance and accuracy over time in stationary tests, and the FSR was good for all antenna positions and fix intervals. However, the LE was affected by the GPS antenna and fix interval. Furthermore, completely or partially obstructed habitats reduced the FSR by up to 80% in households and increased the LE. Movement across habitats had no effect on the FSR, whereas forest habitat influenced the LE. Finally, the mean FSR (0.90 ± 0.26) and LE (15.4 ± 10.1 m) values from low-cost GPS data loggers were comparable to those of built-in wildlife GPS collars (71.6% of fixes with LE < 10 m for motion tests), thus confirming their suitability for use in wildlife studies. PMID:26086958
NASA Astrophysics Data System (ADS)
Hut, Rolf; Bogaard, Thom
2017-04-01
Throwing something in a river and seeing how fast it floats downstream is the first thing that every hydrologists does when encountering a new river. Using a collection of floats allows estimation of gauge surface water velocity and dispersion characteristics. To use floats over long (hundreds of kilometers) stretches of river requires either a crew that keeps an eye on the floats (labor intensive) or having high-tech floats that upload their location on regular intervals, such that they can be retrieved at the end of the experiment. GPS floats with communication units have been custom build by scientists before. Connecting GPS units to GSM modems used to require deep knowledge on micro-electronics and network protocols. In this work we present a version that is build using only off-the-shelf electronics that require no deep knowledge of either micro electronics nor network protocols. The new cellular enabled Particle Electron development board made it possible to connect a Sparkfun OpenLog (SD-card based logger) to a GPS tracker with no soldering and little programming. Because scientist can program the device themselves, settings like sample time can be adapted to the needs of specific experiments and additional sensors can be easily added. When writing GPS location every minute to SD and reporting every fifteen minutes online, our logger can run for three days on a single 2200 mAh LiPo battery (provided with the Particle Electron). Cost of components for our logger is less than 150. The durability of our GPS loggers will be tested during a field campaign at the end of January 2017 where 15 floats will float down the Irrawaddy river over a length of more than 200 km, during two days.
Methods for accurate cold-chain temperature monitoring using digital data-logger thermometers
NASA Astrophysics Data System (ADS)
Chojnacky, M. J.; Miller, W. M.; Strouse, G. F.
2013-09-01
Complete and accurate records of vaccine temperature history are vital to preserving drug potency and patient safety. However, previously published vaccine storage and handling guidelines have failed to indicate a need for continuous temperature monitoring in vaccine storage refrigerators. We evaluated the performance of seven digital data logger models as candidates for continuous temperature monitoring of refrigerated vaccines, based on the following criteria: out-of-box performance and compliance with manufacturer accuracy specifications over the range of use; measurement stability over extended, continuous use; proper setup in a vaccine storage refrigerator so that measurements reflect liquid vaccine temperatures; and practical methods for end-user validation and establishing metrological traceability. Data loggers were tested using ice melting point checks and by comparison to calibrated thermocouples to characterize performance over 0 °C to 10 °C. We also monitored logger performance in a study designed to replicate the range of vaccine storage and environmental conditions encountered at provider offices. Based on the results of this study, the Centers for Disease Control released new guidelines on proper methods for storage, handling, and temperature monitoring of vaccines for participants in its federally-funded Vaccines for Children Program. Improved temperature monitoring practices will ultimately decrease waste from damaged vaccines, improve consumer confidence, and increase effective inoculation rates.
Hydrologic Observatory Data Telemetry Network in an Extreme Environment
NASA Astrophysics Data System (ADS)
Irving, K.; Kane, D.
2007-12-01
A network of hydrological research data stations on the North Slope of Alaska using radio telemetry to gather data in "near real time" will be described. The network consists of approximately 25 research stations, 10 repeater stations, and 3 Internet-connected base stations (though data is also collected at repeater stations and research stations may also function as repeaters). With this operational network, radio link redundancy is sufficient to reach any research station from any base station. The data network is driven in "pull" mode using software running on computers in Fairbanks, and emphasis is placed on reliably collecting and storing data as found on the remote data loggers. Work is underway to deploy dynamic routing software on the controlling computers, at which point the network will be capable of automatically working around problems which may include icing on antennas, satellite sun outages, animal damage, and many others.
Optimal Configuration and Deployment of Software on Multi-Core Processing Architectures
2008-07-01
between the event generating threads and the collector thread is implemented through semaphores . The Perseus data logger is designed to minimize the...performance counters (through the PAPI API) and opens up access to the shared memory logger through a semaphore and Remote Procedure Call (RPC) buffer... synchronization events. Using this rich data, the TMAM is able to output all of the information necessary to identify precisely which pairs of thread
Development open source microcontroller based temperature data logger
NASA Astrophysics Data System (ADS)
Abdullah, M. H.; Che Ghani, S. A.; Zaulkafilai, Z.; Tajuddin, S. N.
2017-10-01
This article discusses the development stages in designing, prototyping, testing and deploying a portable open source microcontroller based temperature data logger for use in rough industrial environment. The 5V powered prototype of data logger is equipped with open source Arduino microcontroller for integrating multiple thermocouple sensors with their module, secure digital (SD) card storage, liquid crystal display (LCD), real time clock and electronic enclosure made of acrylic. The program for the function of the datalogger is programmed so that 8 readings from the thermocouples can be acquired within 3 s interval and displayed on the LCD simultaneously. The recorded temperature readings at four different points on both hydrodistillation show similar profile pattern and highest yield of extracted oil was achieved on hydrodistillation 2 at 0.004%. From the obtained results, this study achieved the objective of developing an inexpensive, portable and robust eight channels temperature measuring module with capabilities to monitor and store real time data.
Chapin, Thomas; Todd, Andrew S.; Zeigler, Matthew P.
2014-01-01
Water temperature and streamflow intermittency are critical parameters influencing aquatic ecosystem health. Low-cost temperature loggers have made continuous water temperature monitoring relatively simple but determining streamflow timing and intermittency using temperature data alone requires significant and subjective data interpretation. Electrical resistance (ER) sensors have recently been developed to overcome the major limitations of temperature-based methods for the assessment of streamflow intermittency. This technical note introduces the STIC (Stream Temperature, Intermittency, and Conductivity logger); a robust, low-cost, simple to build instrument that provides long-duration, high-resolution monitoring of both relative conductivity (RC) and temperature. Simultaneously collected temperature and RC data provide unambiguous water temperature and streamflow intermittency information that is crucial for monitoring aquatic ecosystem health and assessing regulatory compliance. With proper calibration, the STIC relative conductivity data can be used to monitor specific conductivity.
NASA Astrophysics Data System (ADS)
Price, J.; Liff, H.; Lakshmi, V.
2012-12-01
Temperature is considered to be one of the most important physical factors in determining organismal distribution and physiological performance of species in rocky intertidal ecosystems, especially the growth and survival of mussels. However, little is known about the spatial and temporal patterns of temperature in intertidal ecosystems or how those patterns affect intertidal mussel species because of limitations in data collection. We collected in situ temperature at Strawberry Hill, Oregon USA using mussel loggers embedded among the intertidal mussel species, Mytilus californianus. Remotely sensed surface temperatures were used in conjunction with in situ weather and ocean data to determine if remotely sensed surface temperatures can be used as a predictor for changes in the body temperature of a rocky intertidal mussel species. The data used in this study was collected between January 2003 and December 2010. The mussel logger temperatures were compared to in situ weather data collected from a local weather station, ocean data collected from a NOAA buoy, and remotely sensed surface temperatures collected from NASA's sun-synchronous Moderate Resolution Imaging Spectroradiometer aboard the Earth Observing System Aqua and EOS Terra satellites. Daily surface temperatures were collected from four pixel locations which included two sea surface temperature (SST) locations and two land surface temperature (LST) locations. One of the land pixels was chosen to represent the intertidal surface temperature (IST) because it was located within the intertidal zone. As expected, all surface temperatures collected via satellite were significantly correlated to each other and the associated in situ temperatures. Examination of temperatures from the off-shore NOAA buoy and the weather station provide evidence that remotely sensed temperatures were similar to in situ temperature data and explain more variability in mussel logger temperatures than the in situ temperatures. Our results suggest that temperatures (surface temperature and air temperature) are similar across larger spatial scales even when the type of data collection is different. Mussel logger temperatures were strongly correlated to SSTs and were not significantly different than SSTs. Sea surface temperature collected during the Aqua overpass explained 67.1% of the variation in mean monthly mussel logger temperature. When SST, LST, and IST were taken into consideration, nearly 73% of the variation in mussel logger temperature was explained. While in situ monthly air temperature and water temperature explained only 28-33% of the variation in mussel logger temperature. Our results suggests that remotely sensed surface temperatures are reliable and important measurements that can be used to better understand the effects temperature may have on intertidal mussel species in Strawberry Hill, Oregon. Remotely sensed surface temperature could act as a relative indicator of change and may be used to predict general habitat trends and drivers that could directly affect organism body temperature.
Morris, Gail; Conner, L Mike
2017-01-01
Global positioning system (GPS) technologies have improved the ability of researchers to monitor wildlife; however, use of these technologies is often limited by monetary costs. Some researchers have begun to use commercially available GPS loggers as a less expensive means of tracking wildlife, but data regarding performance of these devices are limited. We tested a commercially available GPS logger (i-gotU GT-120) by placing loggers at ground control points with locations known to < 30 cm. In a preliminary investigation, we collected locations every 15 minutes for several days to estimate location error (LE) and circular error probable (CEP). Using similar methods, we then investigated the influence of cover on LE, CEP, and fix success rate (FSR) by constructing cover over ground control points. We found mean LE was < 10 m and mean 50% CEP was < 7 m. FSR was not significantly influenced by cover and in all treatments remained near 100%. Cover had a minor but significant effect on LE. Denser cover was associated with higher mean LE, but the difference in LE between the no cover and highest cover treatments was only 2.2 m. Finally, the most commonly used commercially available devices provide a measure of estimated horizontal position error (EHPE) which potentially may be used to filter inaccurate locations. Using data combined from the preliminary and cover investigations, we modeled LE as a function of EHPE and number of satellites. We found support for use of both EHPE and number of satellites in predicting LE; however, use of EHPE to filter inaccurate locations resulted in the loss of many locations with low error in return for only modest improvements in LE. Even without filtering, the accuracy of the logger was likely sufficient for studies which can accept average location errors of approximately 10 m.
Understanding perceptions of stakeholder groups about Forestry Best Management Practices in Georgia.
Tumpach, Chantal; Dwivedi, Puneet; Izlar, Robert; Cook, Chase
2018-05-01
Forestry Best Management Practices (BMPs) are critical in ensuring sustainable forest management in the United States because of their effectiveness in protecting water quality, reducing soil erosion, maintaining riparian habitat, and sustaining site productivity. The success of forestry BMPs depends heavily on coordination among primary stakeholder groups. It is important to understand perceptions of such groups for a successful forest policy formulation. We used the SWOT-AHP (Strengths, Weaknesses, Opportunities, and Threats analysis with the Analytical Hierarchy Process) framework to assess perceptions of three stakeholder groups (loggers, landowners, agency foresters) about forestry BMPs in Georgia, the largest roundwood producing state in the United States. The agency and logger stakeholder groups gave the highest priority to improved reputation under the strength category, whereas the landowner stakeholder group perceived sustainable forestry as the highest priority under the same category. Lack of landowner education was the highest priority under the weakness category for landowner and agency stakeholder groups, whereas the logger stakeholder group selected lack of trained personnel as the highest priority under the same category. Agency and landowner stakeholder groups gave the highest priority to training and education while loggers indicated maintenance of forest-based environmental benefits as their highest priority under the opportunity category. Finally, landowners and agency stakeholder groups perceived more regulations and restrictions as most significant in the threat category whereas the logger stakeholder group was most concerned about the insufficient accounting of cost sharing under the same category. Overall, selected stakeholder groups recognize the importance of forestry BMPs and had positive perceptions about them. A collaborative approach based on continuous feedback can streamline expectations of stakeholder groups about forestry BMPs in Georgia and several other states that are interested in maintaining high compliance rate of forestry BMPs for ensuring sustainable forest management. Copyright © 2018 Elsevier Ltd. All rights reserved.
An Analysis of Mimosa pudica Leaves Movement by Using LoggerPro Software
NASA Astrophysics Data System (ADS)
Sugito; Susilo; Handayani, L.; Marwoto, P.
2016-08-01
The unique phenomena of Mimosa pudica are the closing and opening movements of its leaves when they got a stimulus. By using certain software, these movements can be drawn into graphic that can be analysed. The LoggerPro provides facilities needed to analyse recorded videos of the plant's reaction to stimulus. Then, through the resulted graph, analysis of some variables can be carried out. The result showed that the plant's movement fits an equation of y = mx + c.
Fine Scale Baleen Whale Behavior Observed Via Tagging Over Daily Time Scales
2014-09-30
During late fall 2013 and winter 2014, I built a data logger for the optical plankton counter ( OPC ) to facilitate its continued use on the NOAA Ship...Gordon Gunter. This ship has very long (> 5 km) of conducting sea cable, and we had communication issues with the OPC with the manufacturers...telemetry system over this long sea cable. To solve this problem, I adapted an existing data logger to provide power and log data from the OPC locally on
NASA Astrophysics Data System (ADS)
Salvador-Franch, Ferran; Salvà-Catarineu, Montserrat; Oliva, Marc; Gómez-Ortiz, Antonio
2016-04-01
Glaciers shaped the headwaters and valley floors in the Eastern Pyrenees during the Last Glaciation at elevations above 2100-2200 m. Since the deglaciation of these areas, periglacial processes have generated a wide range of periglacial landforms, such as rock glaciers, patterned ground and debris slopes. The role of soil temperatures is decisive for the degree of activity of periglacial processes: cryoturbation, solifluction, frost weathering, etc. Nowadays, periglacial processes in the Eastern Pyrenees are driven by a seasonal frozen layer extending 5-7 months. In general, at 2100 m the seasonal frost reaches 20 cm depth, while at 2700 m reaches 50 cm depth. However, soil temperatures, and thus, periglacial processes are strongly controlled by the large interannual variability of the snow cover. With the purpose of understanding the rhythm and intensity of soil freezing/thawing in 2003 we set up several monitoring sites along a vertical transect from the valley floors (1100 m) to the high plateaus (2700 m) across the southern slope of the Puigpedrós massif (2914 m), in the Eastern Pyrenees. The monitoring of soil temperatures has been conducted from 2003 to 2015 in different periglacial landforms using UTL and Hobo loggers. These loggers were installed at depths of 5, 20 and 50 cm at five sites: Calmquerdós (2730 m), Malniu (2230 m), La Feixa (2150 m), Meranges (1600 m) and Das (1097 m). Air temperatures used as reference come from two automatic stations of the Catalan Meteorological Survey in Malniu and Das, and with two loggers installed in La Feixa and Meranges. No permafrost regime was detected in none of the sites. Data shows evidence of the control of snow cover on the depth of the frozen layer and on the number of freeze-thaw cycles. Air temperatures at 2000-2200 m show a mean of 150 freeze-thaw cycles per year. In La Feixa, with very thin snow cover, only 67 cycles are recorded at 5 cm depth and 5 cycles at 50 cm depth. In Malniu, located at a higher elevation showing a thicker and longer snow cover, only 17 freeze-thaw cycles per year are recorded at 5 cm depth, with no cycles recorded at 50 cm depth. Soils remain unfrozen during years with a very thick snow cover. The snow cover is also largely conditioned by the microtopography and exposure to the dominant winds. These factors condition the distribution, duration and intensity of the frozen ground and, thus, determine the intensity of periglacial processes in these areas.
NASA Astrophysics Data System (ADS)
Salvador-Franch, Ferran; Salvà-Catarineu, Montserrat; Oliva, Marc; Gómez-Ortiz, Antonio
2015-04-01
During the Last Glaciation glaciers shaped the headwaters and valley floors in the Eastern Pyrenees above 2100-2200 m. Since the deglaciation of these high mountain environments, periglacial processes have generated rock glaciers, patterned ground and debris slopes. The role of soil temperatures is decisive regarding the contemporary activity of several processes: cryoturbation, solifluction, frost weathering, etc. Nowadays, periglacial processes are driven by a seasonal frozen layer extending 4-5 months. At 2100 m the seasonal frost reaches 20 cm depth, while at 2700 m reaches 50 cm depth. However, soil temperatures, and thus, periglacial processes are strongly controlled by the large interannual variability of the snow cover. With the purpose of understanding the rhythm and intensity of soil freezing/thawing we have set up several monitoring sites along a vertical transect from the high plateaus (2700 m) to the valley floors (1100 m) across the southern slope of the Puigpedrós massif (2914 m), in the Eastern Pyrenees. The monitoring of soil temperatures extends from 2003 to 2014. TinyTalk, UTL and Hobo loggers have been used in this study. These loggers were installed at depths of -5, -20 and -50 cm at five sites: Calmquerdós (2730 m), Malniu (2230 m), La Feixa (2150 m), Meranges (1600 m) and Das (1097 m). Air temperatures used as reference come from two automatic stations of the Catalan Meteorological Survey (Malniu, Das) as well as from two loggers installed in La Feixa and Meranges. Data shows the control of snow cover on the depth of the frozen layer and on the number of freeze-thaw cycles. Air temperatures at 2000-2200 m show a mean of 150 freeze-thaw cycles per year. In La Feixa, with very thin snow cover, only 67 cycles are recorded at 5 cm depth and 5 cycles at 50 cm depth. In Malniu, located at a higher elevation showing a thicker and longer snow cover, only 17 freeze-thaw cycles per year are recorded at 5 cm depth, with no cycles recorded at 50 cm depth. Soils remain unfrozen during years with a very thick snow cover. The snow cover is also largely conditioned by the microtopography and exposure to the dominant winds. These factors condition the distribution, duration and intensity of the frozen ground and, thus, determine the intensity of periglacial processes in these areas.
A portable data-logging system for industrial hygiene personal chlorine monitoring.
Langhorst, M L; Illes, S P
1986-02-01
The combination of suitable portable sensors or instruments with small microprocessor-based data-logger units has made it possible to obtain detailed monitoring data for many health and environmental applications. Following data acquisition in field use, the logged data may be transferred to a desk-top personal computer for complete flexibility in manipulation of data and formating of results. A system has been assembled from commercial components and demonstrated for chlorine personal monitoring applications. The system consists of personal chlorine sensors, a Metrosonics data-logger and reader unit, and an Apple II Plus personal computer. The computer software was developed to handle sensor calibration, data evaluation and reduction, report formating and long-term storage of raw data on a disk. This system makes it possible to generate time-concentration profiles, evaluate dose above a threshold, quantitate short-term excursions and summarize time-weighted average (TWA) results. Field data from plant trials demonstrated feasibility of use, ruggedness and reliability. No significant differences were found between the time-weighted average chlorine concentrations determined by the sensor/logger system and two other methods: the sulfamic acid bubbler reference method and the 3M Poroplastic diffusional dosimeter. The sensor/data-logger system, however, provided far more information than the other two methods in terms of peak excursions, TWAs and exposure doses. For industrial hygiene applications, the system allows better definition of employee exposures, particularly for chemicals with acute as well as chronic health effects.(ABSTRACT TRUNCATED AT 250 WORDS)
Open Source Hardware for DIY Environmental Sensing
NASA Astrophysics Data System (ADS)
Aufdenkampe, A. K.; Hicks, S. D.; Damiano, S. G.; Montgomery, D. S.
2014-12-01
The Arduino open source electronics platform has been very popular within the DIY (Do It Yourself) community for several years, and it is now providing environmental science researchers with an inexpensive alternative to commercial data logging and transmission hardware. Here we present the designs for our latest series of custom Arduino-based dataloggers, which include wireless communication options like self-meshing radio networks and cellular phone modules. The main Arduino board uses a custom interface board to connect to various research-grade sensors to take readings of turbidity, dissolved oxygen, water depth and conductivity, soil moisture, solar radiation, and other parameters. Sensors with SDI-12 communications can be directly interfaced to the logger using our open Arduino-SDI-12 software library (https://github.com/StroudCenter/Arduino-SDI-12). Different deployment options are shown, like rugged enclosures to house the loggers and rigs for mounting the sensors in both fresh water and marine environments. After the data has been collected and transmitted by the logger, the data is received by a mySQL-PHP stack running on a web server that can be accessed from anywhere in the world. Once there, the data can be visualized on web pages or served though REST requests and Water One Flow (WOF) services. Since one of the main benefits of using open source hardware is the easy collaboration between users, we are introducing a new web platform for discussion and sharing of ideas and plans for hardware and software designs used with DIY environmental sensors and data loggers.
ERIC Educational Resources Information Center
Benade, Leon
2011-01-01
The revised New Zealand Curriculum became mandatory for use in New Zealand schools in February 2010. The ongoing reform agenda in education in New Zealand since 1989 and elsewhere internationally has had corrosive effects on teacher professionality. State-driven neo-liberal policy and education reforms are deeply damaging to the mental and moral…
A preliminary evaluation of a reusable digital sterilization indicator prototype.
Puttaiah, R; Griggs, J; D'Onofrio, M
2014-09-01
Sterilization of critical and semicritical instruments used in patient care must undergo a terminal process of sterilization. Use of chemical and physical indicators are important in providing information on the sterilizer's performance during each cycle. Regular and periodic monitoring of sterilizers using biological indicators is necessary in periodically validating performance of sterilizers. Data loggers or independent digital parametric indicators are innovative devices that provide more information than various classes chemical indicators. In this study we evaluated a prototype of an independent digital parametric indicator's use in autoclaves. The purpose of this study was to evaluate the performance of an independent digital indicator/data logger prototype (DS1922F) that could be used for multiple cycles within an autoclave.MG Materials and methods: Three batches of the DS1922F (150 samples) were used in this study that was conducted in a series. The first batch was challenged with 300 sterilization cycles within an autoclave and the data loggers evaluated to study failures and the reason for failure, make corrections and improve the prototype design. After changes made based on studying the first batch, the second batch of the prototype (150 samples) were challenged once again with 300 sterilization cycles within an autoclave and failure studied again in further improvement of the prototype. The final batch (3rd batch) of the prototype (150 samples) was challenged again but with 600 cycles to see how long they would last. Kaplan-Meier survival analysis analyses of all three batches was conducted (α = 0.05) and failed samples qualitatively studied in understanding the variables involved in the failure of the prototype, and in improving quality. Each tested batch provided crucial information on device failure and helped in improvement of the prototype. Mean lifetime survival of the final batch (Batch 3) of prototype was 498 (480, 516) sterilization cycles in an autoclave. In this study, the final batch of the DS1922F prototype data logger was found to be robust in withstanding the challenge of 600 autoclave cycles, with a mean lifetime of more than 450 cycles, multiple times more than prescribed number of cycles. Instrument reprocessing is among the important aspects of infection control. While stringent procedures are followed in instrument reprocessing within the clinic in assuring patient safety, regular use of sterilization process indicators and periodic biological validation of the sterilizer's performance is necessary. Chemical indicators for use in Autoclaves provide information on whether the particular cycle's parameters were achieved but do not provide at what specific point in time or temperature the failure occurred. Data loggers and associated reader software as the tested prototype in this evaluation (DS1922F), are designed to provide continuous information on time and temperature of the prescribed cycle. Data loggers provide immediate information on the process as opposed to Biological Indicators that take from days to a week in obtaining a confirmatory result. Further, many countries do not have the sterilization monitoring service infrastructure to meet the demands of the end users. In the absence of sterilization monitoring services, use of digital data loggers for each sterilization cycle is more pragmatic.
Zacour, Brian M; Pandey, Preetanshu; Subramanian, Ganeshkumar; Gao, Julia Z; Nikfar, Faranak
2014-06-01
The objective of this study was to determine the impact that the micro-environment, as measured by PyroButton data loggers, experienced by tablets during the pan coating unit operation had on the layer adhesion of bilayer tablets in open storage conditions. A full factorial design of experiments (DOE) with three center points was conducted to study the impact of final tablet hardness, film coating spray rate and film coating exhaust temperature on the delamination tendencies of bilayer tablets. PyroButton data loggers were placed (fixed) at various locations in a pan coater and were also allowed to freely move with the tablet bed to measure the micro-environmental temperature and humidity conditions of the tablet bed. The variance in the measured micro-environment via PyroButton data loggers accounted for 75% of the variance in the delamination tendencies of bilayer tablets on storage (R(2 )= 0.75). A survival analysis suggested that tablet hardness and coating spray rate significantly impacted the delamination tendencies of the bilayer tablets under open storage conditions. The coating exhaust temperature did not show good correlation with the tablets' propensity to crack indicating that it was not representative of the coating micro-environment. Models created using data obtained from the PyroButton data loggers outperformed models created using primary DOE factors in the prediction of bilayer tablet strength, especially upon equipment or scale transfers. The coating micro-environment experienced by tablets during the pan coating unit operation significantly impacts the strength of the bilayer interface of tablets on storage.
A comparison in Colorado of three methods to monitor breeding amphibians
Corn, P.S.; Muths, E.; Iko, W.M.
2000-01-01
We surveyed amphibians at 4 montane and 2 plains lentic sites in northern Colorado using 3 techniques: standardized call surveys, automated recording devices (frog-loggers), and intensive surveys including capture-recapture techniques. Amphibians were observed at 5 sites. Species richness varied from 0 to 4 species at each site. Richness scores, the sums of species richness among sites, were similar among methods: 8 for call surveys, 10 for frog-loggers, and 11 for intensive surveys (9 if the non-vocal salamander Ambystoma tigrinum is excluded). The frog-logger at 1 site recorded Spea bombifrons which was not active during the times when call and intensive surveys were conducted. Relative abundance scores from call surveys failed to reflect a relatively large population of Bufo woodhousii at 1 site and only weakly differentiated among different-sized populations of Pseudacris maculata at 3 other sites. For extensive applications, call surveys have the lowest costs and fewest requirements for highly trained personnel. However, for a variety of reasons, call surveys cannot be used with equal effectiveness in all parts of North America.
DOE Office of Scientific and Technical Information (OSTI.GOV)
HUBER, J.H.
An Enraf Densitometer is installed on tank 241-AY-102. The Densitometer will frequently be tasked to obtain and log density profiles. The activity can be effected a number of ways. Enraf Incorporated provides a software package called ''Logger18'' to its customers for the purpose of in-shop testing of their gauges. Logger18 is capable of accepting an input file which can direct the gauge to obtain a density profile for a given tank level and bottom limit. Logger18 is a complex, DOS based program which will require trained technicians and/or tank farm entries to obtain the data. ALARA considerations have prompted themore » development of a more user-friendly, computer-based interface to the Enraf densitometers. This document records the plan by which this new Enraf data acquisition software will be developed, reviewed, verified, and released. This plan applies to the development and implementation of a one-time-use software program, which will be called ''Enraf Control Panel.'' The software will be primarily used for remote operation of Enraf Densitometers for the purpose of obtaining and logging tank product density profiles.« less
In vitro simulation of fretting-corrosion in hip implant modular junctions: The influence of pH.
Royhman, Dmitry; Patel, Megha; Jacobs, Joshua J; Wimmer, Markus A; Hallab, Nadim J; Mathew, Mathew T
2018-02-01
The fretting-corrosion behavior of mixed metal contacts is affected by various mechanical and electrochemical parameters. Crevice conditions at the junction and patient-specific pathologies can affect the pH of the prosthetic environment. The main objective of this study is to understand the effect of pH variation at the stem/head junction of the hip implant under fretting corrosion exposure. We hypothesized that pH will have a significant influence on the fretting-corrosion behavior hip implant modular junctions. A custom-made setup was used to evaluate the fretting corrosion behavior of hip implant modular junctions. A Newborn calf serum solution (30 g/L protein content) was used to simulate the synovial fluid environment. A sinusoidal fretting motion, with a displacement amplitude of +50 µm, was applied to the Ti alloy rod. The effects of pathology driven, periprosthetic pH variation were simulated at four different pH levels (3.0, 4.5, 6.0 and 7.6). Electrochemical and mechanical properties were evaluated before, during, and after the applied fretting motion. The impedance of the system was increased in response to the fretting motion. The hysteresis tangential load/displacement behavior was not affected by pH level. The worn surfaces of CoCrMo pins exhibited the presence of tribolayer or organic deposits, in the pH 4.5 group, which may explain the lower drop in potential and mass loss observed in that group. Mechanically dominated wear mechanisms, namely, adhesive wear was shown in the pH 7.6 group, which may account for a higher potential drop and metal content loss. This study suggests that the fretting-corrosion mechanisms in hip implant are affected by the pH levels of the surrounding environment and patient-specific factors. Copyright © 2017. Published by Elsevier Ltd.
Flow accelerated organic coating degradation
NASA Astrophysics Data System (ADS)
Zhou, Qixin
Applying organic coatings is a common and the most cost effective way to protect metallic objects and structures from corrosion. Water entry into coating-metal interface is usually the main cause for the deterioration of organic coatings, which leads to coating delamination and underfilm corrosion. Recently, flowing fluids over sample surface have received attention due to their capability to accelerate material degradation. A plethora of works has focused on the flow induced metal corrosion, while few studies have investigated the flow accelerated organic coating degradation. Flowing fluids above coating surface affect corrosion by enhancing the water transport and abrading the surface due to fluid shear. Hence, it is of great importance to understand the influence of flowing fluids on the degradation of corrosion protective organic coatings. In this study, a pigmented marine coating and several clear coatings were exposed to the laminar flow and stationary immersion. The laminar flow was pressure driven and confined in a flow channel. A 3.5 wt% sodium chloride solution and pure water was employed as the working fluid with a variety of flow rates. The corrosion protective properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. Equivalent circuit models were employed to interpret the EIS spectra. The time evolution of coating resistance and capacitance obtained from the model was studied to demonstrate the coating degradation. Thickness, gloss, and other topography characterizations were conducted to facilitate the assessment of the corrosion. The working fluids were characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The influence of flow rate, fluid shear, fluid composition, and other effects in the coating degradation were investigated. We conclude that flowing fluid on the coating surface accelerates the transport of water, oxygen, and ions into the coating, as well as promotes the migration of coating materials from the coating into the working fluid, where coatings experience more severe deterioration in their barrier property under flowing conditions. Pure water has shown to be a much more aggressive working fluid than electrolyte solutions. The flowing fluid over the coating surface could be used as an effective acceleration method.
Multiscale processing of loss of metal: a machine learning approach
NASA Astrophysics Data System (ADS)
De Masi, G.; Gentile, M.; Vichi, R.; Bruschi, R.; Gabetta, G.
2017-07-01
Corrosion is one of the principal causes of degradation to failure of marine structures. In practice, localized corrosion is the most dangerous mode of attack and can result in serious failures, in particular in marine flowlines and inter-field lines, arousing serious concerns relatively to environmental impact. The progress in time of internal corrosion, the location along the route and across the pipe section, the development pattern and the depth of the loss of metal are a very complex issue: the most important factors are products characteristics, transport conditions over the operating lifespan, process fluid-dynamics, and pipeline geometrical configuration. Understanding which factors among them play the most important role is a key step to develop a model able to predict with enough accuracy the sections more exposed to risk of failure. Some factors play a crucial role at certain spatial scales while other factors at other scales. The Mutual Information Theory, intimately related to the concept of Shannon Entropy in Information theory, has been applied to detect the most important variables at each scale. Finally, the variables emerged from this analysis at each scale have been integrated in a predicting data driven model sensibly improving its performance.
Field tests of a chemiresistor sensor for in-situ monitoring of vapor-phase contaminants
NASA Astrophysics Data System (ADS)
Ho, C.; McGrath, L.; Wright, J.
2003-04-01
An in-situ chemiresistor sensor has been developed that can detect volatile organic compounds in subsurface environmental applications. Several field tests were conducted in 2001 and 2002 to test the reliability, operation, and performance of the in-situ chemiresistor sensor system. The chemiresistor consists of a carbon-loaded polymer deposited onto a microfabricated circuit. The polymer swells reversibly in the presence of volatile organic compounds as vapor-phase molecules absorb into the polymer, causing a change in the electrical resistance of the circuit. The change in resistance can be calibrated to known concentrations of analytes, and arrays of chemiresistors can be used on a single chip to aid in discrimination. A waterproof housing was constructed to allow the chemiresistor to be used in a variety of media including air, soil, and water. The integrated unit, which can be buried in soils or emplaced in wells, is connected via cable to a surface-based solar-powered data logger. A cell-phone modem is used to automatically download the data from the data logger on a periodic basis. The field tests were performed at three locations: (1) Edwards Air Force Base, CA; (2) Nevada Test Site; and (3) Sandia's Chemical Waste Landfill near Albuquerque, NM. The objectives of the tests were to evaluate the ruggedness, longevity, operation, performance, and engineering requirements of these sensors in actual field settings. Results showed that the sensors could be operated continuously for long periods of time (greater than a year) using remote solar-powered data-logging stations with wireless telemetry. The sensor housing, which was constructed of 304 stainless steel, showed some signs of corrosion when placed in contaminated water for several months, but the overall integrity was maintained. The detection limits of the chemiresistors were generally found to be near 0.1% of the saturated vapor pressure of the target analyte in controlled laboratory conditions (e.g., ~100 ppmv for TCE), but fluctuations in environmental parameters and other interferences increased the detection limit by about an order of magnitude in the field tests. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.
Coupled oscillators: interesting experiments for high school students
NASA Astrophysics Data System (ADS)
Kodejška, Č.; Lepil, O.; Sedláčková, H.
2018-07-01
This work deals with the experimental demonstration of coupled oscillators using simple tools in the form of mechanical coupled pendulums, magnetically coupled elastic strings or electromagnetic oscillators. For the evaluation of results the data logger Lab Quest Vernier and video analysis in the Tracker program were used. In the first part of this work, coupled mechanical oscillators of different types are shown and the data analysis by the Tracker or Vernier Logger Pro programs. The second part describes a measurement using two LC circuits with inductively or capacitive coupled electromagnetic oscillators and the obtained experimental results.
McColloster, Patrick; Vallbona, Carlos
2011-01-01
We conducted the first US study using graphic-output temperature data loggers in quantifying cold chain failure. Fifty-four vaccine refrigerators of a county outpatient health system were studied. Forty-eight percent maintained temperatures of 2°C to 8°C and 24% had protracted periods of temperatures less than 0°C. The correlation between the percentage of refrigerators with freezing temperatures and the pertussis rate for each health region was r = 0.76. The findings suggest that improper vaccine storage may have contributed to recent increases in pertussis rates.
Teaching Science with Technology
NASA Astrophysics Data System (ADS)
Gornostaeva, Svetlana
2015-04-01
This is a short introduction about me, description of different teaching methods, which is used in my teaching practice of Geography, biology and GIS systems education. The main part is tell about practical lesson with lab Vernier. My name is Svetlana Gornostaeva. I am a geography, biology and GIS systems teacher in Tallinn Mustjõe Gymnasium (www.mjg.ee) and private school Garant (http://www.erakoolgarant.ee/). In my teaching practice I do all to show that science courses are very important, interesting, and do not difficult. I use differentiated instruction methods also consider individual needs. At lessons is used different active teaching methods such as individual work of various levels of difficulty, team works, creative tasks, interactive exercises, excursions, role-playing games, meeting with experts. On my lessons I use visual aids (maps, a collection of rocks and minerals, herbarium, posters, Vernier data logger). My favorite teaching methods are excursions, meeting with experts and practical lesson with lab Vernier. A small part of my job demonstrate my poster. In the next abstract I want to bring a one practical work with Vernier which I do with my students, when we teach a theme "Atmosphere and climate". OUTDOOR LEARNING. SUBJECT "ATMOSPHERE AND CLIMATE". WEATHER OBSERVATIONS WITH VERNIER DATA LOGGER. The aim: students teach to use Vernier data logger and measure climatic parameters such as: temperature, humidity, atmospheric pressure, solar radiation, ultraviolet light radiation, wind speed. In working process pupils also teach work together, observe natural processes, analyze. Children are working by small groups, 4-5 in each group. Every one should personally measure all parameters and put numbers into the table. After it group observe cloudiness, analyze table and give conclusion "Is at this moment dominates cyclone or anticyclone ?". Children really like this kind of job. Vernier data logger it is really fantastic tool. It is mobile lab. This system give possibilities to easy and fast observe nature process in dynamic. Vernier puts easy-to-use data loggers, sensors, experiments and graphing/analysis software into the hands of students, helping educators develop the next generation of scientists and engineers. You also can do a bit fun with Vernier. For instance, children, who finished their job faster with anemometer can give answer to the question : whom lungs are bigger?" or with thermometer give answer to the question : who has the hottest hands?". Also with thermometer children can draw a rabbit or a mountain. I convinced that Vernier data logger with sensors should be in each school. SUMMARY Personally I am young teacher and do not have a lot of work experience, but I really like my work and do all to share my skills to my students.
Lamb, Juliet S.; Satgé, Yvan G.; Fiorello, Christine V.; Jodice, Patrick G. R.
2017-01-01
Although the use of bird-borne data loggers has become widespread in avian field research, the effects of capture and transmitter attachment on behavior and demographic rates are not often measured. Tag- and capture-induced effects on individual behavior, survival and reproduction may limit extrapolation of transmitter data to wider populations. However, measuring individual responses to capture and tagging is a necessary step in developing research techniques that minimize negative effects. We measured the short-term behavioral effects of handling and GPS transmitter attachment on Brown Pelicans under both captive and field conditions, and followed tagged individuals through a full breeding season to assess whether capture and transmitter attachment increased rates of nest abandonment or breeding failure. We observed slight increases in preening among tagged individuals 0–2 h after capture relative to controls that had not been captured or tagged, with a corresponding reduction in time spent resting. One to three days post-capture, nesting behavior of tagged pelicans resembled that of neighbors that had not been captured or tagged. Eighty-eight percent of tagged breeders remained at the same nest location for more than 48 h after capture, attending nests and chicks for an average of 49 days, and 51% were assumed to successfully fledge young. Breeding success was driven primarily by variation in location; however, sex and handling time also influenced the probability of successful breeding in tagged pelicans, suggesting that individual characteristics and the capture process itself can confound the effects of capture and transmitter attachment. We conclude that pelicans fitted with GPS transmitters exhibit comparable behaviors to untagged individuals within a day of capture and that GPS tracking is a viable technique for studying behavior and demography in this species. We also identify measures to minimize post-capture nest abandonment rates in tracking studies, including minimizing handling time and covering nests during processing.
Chen, Le; Yang, Jinhui; Klaus, Shannon; Lee, Lyman J; Woods-Robinson, Rachel; Ma, Jie; Lum, Yanwei; Cooper, Jason K; Toma, Francesca M; Wang, Lin-Wang; Sharp, Ian D; Bell, Alexis T; Ager, Joel W
2015-08-05
Achieving stable operation of photoanodes used as components of solar water splitting devices is critical to realizing the promise of this renewable energy technology. It is shown that p-type transparent conducting oxides (p-TCOs) can function both as a selective hole contact and corrosion protection layer for photoanodes used in light-driven water oxidation. Using NiCo2O4 as the p-TCO and n-type Si as a prototypical light absorber, a rectifying heterojunction capable of light driven water oxidation was created. By placing the charge separating junction in the Si using a np(+) structure and by incorporating a highly active heterogeneous Ni-Fe oxygen evolution catalyst, efficient light-driven water oxidation can be achieved. In this structure, oxygen evolution under AM1.5G illumination occurs at 0.95 V vs RHE, and the current density at the reversible potential for water oxidation (1.23 V vs RHE) is >25 mA cm(-2). Stable operation was confirmed by observing a constant current density over 72 h and by sensitive measurements of corrosion products in the electrolyte. In situ Raman spectroscopy was employed to investigate structural transformation of NiCo2O4 during electrochemical oxidation. The interface between the light absorber and p-TCO is crucial to produce selective hole conduction to the surface under illumination. For example, annealing to produce more crystalline NiCo2O4 produces only small changes in its hole conductivity, while a thicker SiOx layer is formed at the n-Si/p-NiCo2O4 interface, greatly reducing the PEC performance. The generality of the p-TCO protection approach is demonstrated by multihour, stable, water oxidation with n-InP/p-NiCo2O4 heterojunction photoanodes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fishbaugher, M. J.
1985-05-01
The decreasing cost of microcomputers along with improvements in power metering circuitry have changed the way in which electrical energy use is monitored. Although utilities still rely on kilowatt-hour (kWh) meters for billing purposes, a microcomputer-based monitoring system is used when greater temporal and end-use resolution is desired. Because these types of monitoring systems will be used increasingly in large-scale conservation and end-use studies, it is important that their performance be analyzed to determine their accuracy. A co-instrumentation test was devised in which two such microcomputer-based monitoring systems made simultaneous measurements of electrical end-uses in two commercial buildings. The analysismore » of the co-instrumentation data aids in the evaluation of microcomputer-based monitoring systems used for end-use measurements. Separate and independent data loggers were used to measure the same loads simultaneously. In addition to these two systems, a utility billing meter measured the total energy use in each building during the co-instrumentation test. The utility's meters provided a relatively accurate standard by which the performance of both loggers could be judged. The comparison between the SCL and PNL microcomputer-based loggers has shown that power measurement techniques directly affect system performance. The co-instrumentation test has shown that there are certain standards that a monitoring system must meet if it is to perform well. First, it is essential to calibrate a microcomputer-based logger against a known standard load before the system is installed. Second, a microcomputer-based system must have some way of accounting for power factors. Recent advances in power metering circuitry have made it relatively easy to apply these power factors automatically in real time.« less
Miller, Thomas D; Maxwell, Andrew J; Lindquist, Thomas D; Requard, Jake
2013-01-01
To determine the cooling effect of generic insulated shipping containers in ambient and high-temperature environments. Twenty-seven shipping containers were packed with wet ice according to industry standards. The ice in each container was weighed. Ambient temperatures were recorded by data loggers affixed to the exterior. Internal temperatures were recorded by data loggers packed inside the containers, for as long as the data loggers remained at ≤8°C. The cooling effect, or minutes per gram of ice a data logger maintained a temperature of ≤8°C, was calculated using linear regression; 8 similar containers were subjected to elevated summer temperatures. Small, medium, and large containers held mean masses of wet ice of 685, 1929, and 4439 g, respectively. The linear regression equation for grams of ice to duration of time at ≤8°C was y = 0.1994x + 385.13 for small containers, y = 0.1854x + 1273.3 for medium, and y = 0.5892x + 1410.3 for large containers, resulting in a cooling effect of 25.1 hours for small, 58.9 hours for medium, and 85.7 hours for large containers at ambient temperature. The duration of cooling effect in the summer profile group was consistent with that of the ambient temperature group. All of the container sizes successfully maintained proper cooling when packed with the appropriate grams of wet ice for the needed time interval. This study validates current practice for the shipment of corneal tissue in inexpensive, generic containers that can maintain effective cooling for the duration required for local, national, and international shipment.
MISSE 1 and 2 Tray Temperature Measurements
NASA Technical Reports Server (NTRS)
Harvey, Gale A.; Kinard, William H.
2006-01-01
The Materials International Space Station Experiment (MISSE 1 & 2) was deployed August 10,2001 and retrieved July 30,2005. This experiment is a co-operative endeavor by NASA-LaRC. NASA-GRC, NASA-MSFC, NASA-JSC, the Materials Laboratory at the Air Force Research Laboratory, and the Boeing Phantom Works. The objective of the experiment is to evaluate performance, stability, and long term survivability of materials and components planned for use by NASA and DOD on future LEO, synchronous orbit, and interplanetary space missions. Temperature is an important parameter in the evaluation of space environmental effects on materials. The MISSE 1 & 2 had autonomous temperature data loggers to measure the temperature of each of the four experiment trays. The MISSE tray-temperature data loggers have one external thermistor data channel, and a 12 bit digital converter. The MISSE experiment trays were exposed to the ISS space environment for nearly four times the nominal design lifetime for this experiment. Nevertheless, all of the data loggers provided useful temperature measurements of MISSE. The temperature measurement system has been discussed in a previous paper. This paper presents temperature measurements of MISSE payload experiment carriers (PECs) 1 and 2 experiment trays.
Dahlqvist, Camilla; Hansson, Gert-Åke; Forsman, Mikael
2016-07-01
Repetitive work and work in constrained postures are risk factors for developing musculoskeletal disorders. Low-cost, user-friendly technical methods to quantify these risks are needed. The aims were to validate inclination angles and velocities of one model of the new generation of accelerometers with integrated data loggers against a previously validated one, and to compare meaurements when using a plain reference posture with that of a standardized one. All mean (n = 12 subjects) angular RMS-differences in 4 work tasks and 4 body parts were <2.5° and all mean median angular velocity differences <5.0 °/s. The mean correlation between the inclination signal-pairs was 0.996. This model of the new generation of triaxial accelerometers proved to be comparable to the validated accelerometer using a data logger. This makes it well-suited, for both researchers and practitioners, to measure postures and movements during work. Further work is needed for validation of the plain reference posture for upper arms. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.
A Temperature-Monitoring Vaginal Ring for Measuring Adherence
Boyd, Peter; Desjardins, Delphine; Kumar, Sandeep; Fetherston, Susan M.; Le-Grand, Roger; Dereuddre-Bosquet, Nathalie; Helgadóttir, Berglind; Bjarnason, Ásgeir; Narasimhan, Manjula; Malcolm, R. Karl
2015-01-01
Background Product adherence is a pivotal issue in the development of effective vaginal microbicides to reduce sexual transmission of HIV. To date, the six Phase III studies of vaginal gel products have relied primarily on self-reporting of adherence. Accurate and reliable methods for monitoring user adherence to microbicide-releasing vaginal rings have yet to be established. Methods A silicone elastomer vaginal ring prototype containing an embedded, miniature temperature logger has been developed and tested in vitro and in cynomolgus macaques for its potential to continuously monitor environmental temperature and accurately determine episodes of ring insertion and removal. Results In vitro studies demonstrated that DST nano-T temperature loggers encapsulated in medical grade silicone elastomer were able to accurately and continuously measure environmental temperature. The devices responded quickly to temperature changes despite being embedded in different thickness of silicone elastomer. Prototype vaginal rings measured higher temperatures compared with a subcutaneously implanted device, showed high sensitivity to diurnal fluctuations in vaginal temperature, and accurately detected periods of ring removal when tested in macaques. Conclusions Vaginal rings containing embedded temperature loggers may be useful in the assessment of product adherence in late-stage clinical trials. PMID:25965956
Development of Thermal Radiation Experiments Kit Based on Data Logger for Physics Learning Media
NASA Astrophysics Data System (ADS)
Permana, H.; Iswanto, B. H.
2018-04-01
Thermal Radiation Experiments Kit (TREK) based on data logger for physics learning media was developed. TREK will be used as a learning medium on the subject of Temperature and Heat to explain the concept of emissivity of a material in grade XI so that it can add variations of experiments which are commonly done such as thermal expansion, transfer of thermal energy (conduction, convection, and radiation), and specific heat capacity. DHT11 sensor is used to measure temperature and microcontroller Arduino-uno used as data logger. The object tested are in the form of coated glass thin films and aluminum with different colors. TREK comes with a user manual and student worksheet (LKS) to make it easier for teachers and students to use. TREK was developed using the ADDIE Development Model (Analyze, Design, Development, Implementation, and Evaluation). And validated by experts, physics teachers, and students. Validation instrument is a questionnaire with a five-item Likert response scale with reviewed aspect coverage: appropriate content and concepts, design, and user friendly. The results showed that TREK was excellent (experts 88.13%, science teachers 95.68%, and students 85.77%).
VAB Temperature and Humidity Study
NASA Technical Reports Server (NTRS)
Lane, John E.; Youngquist, Robert C.; Muktarian, Edward; Nurge, Mark A.
2014-01-01
In 2012, 17 data loggers were placed in the VAB to measure temperature and humidity at 10-minute intervals over a one-year period. In 2013, the data loggers were replaced with an upgraded model and slight adjustments to their locations were made to reduce direct solar heating effects. The data acquired by the data loggers was compared to temperature data provided by three wind towers located around the building. It was found that the VAB acts as a large thermal filter, delaying and reducing the thermal oscillations occurring outside of the building. This filtering is typically more pronounced at higher locations in the building, probably because these locations have less thermal connection with the outside. We surmise that the lower elevations respond more to outside temperature variations because of air flow through the doors. Temperatures inside the VAB rarely exceed outdoor temperatures, only doing so when measurements are made directly on a surface with connection to the outside (such as a door or wall) or when solar radiation falls directly on the sensor. A thermal model is presented to yield approximate filter response times for various locations in the building. Appendix A contains historical thermal and humidity data from 1994 to 2009.
Calculation of air movement in ice caves by using the CalcFlow method
NASA Astrophysics Data System (ADS)
Meyer, Christiane; Pflitsch, Andreas; Maggi, Valter
2017-04-01
We present a method to determine the air flow regime within ice caves by temperature loggers. Technical capabilities of conducting airflow measurements are restricted by the availability of energy at the ice cave study sites throughout the year. Though the knowledge of the airflow regime is a prerequisite for the understanding of the cave climate. By cross-correlating different time series of air temperature measurements inside a cave, we define the travel time of the air between the loggers, which corresponds to the time shift of best correlation, and use this result to derive the airflow speed. Then we estimate the temperature biases and scale factors for the temperature variations observed by the different loggers by a least squares adjustment. As quality control for bias and scale we use the formal errors of the estimation process. For the calculated airflow speed quality criteria are developed by use of a simulation study. Furthermore we will apply the method to temperature measurements in the static ice cave Schellenberger Eishöhle (Germany). In the end we show how the method can be used as an advanced filter for the separation of different signal contents of the temperature measurements.
Prediction of parturition in bitches utilizing continuous vaginal temperature measurement.
Geiser, B; Burfeind, O; Heuwieser, W; Arlt, S
2014-02-01
The objective of this study was to determine sensitivity and specificity of a body temperature decline in bitches to predict parturition. Temperature loggers were placed into the vaginal cavity of 16 pregnant bitches on day 56-61 after estimated ovulation or first mating. This measurement technique has been validated previously and enabled continuous sampling of body temperature. The temperature loggers were expelled from the vagina before delivery of the first pup. The computed values for specificity (77-92%) were higher than sensitivity (53-69%), indicating a more precise prognosis of parturition not occurring. In conclusion, our findings may assist interpreting vaginal temperature measurements in order to predict parturition in bitches. © 2013 Blackwell Verlag GmbH.
Development of autonomous gamma dose logger for environmental monitoring
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jisha, N. V.; Krishnakumar, D. N.; Surya Prakash, G.
2012-03-15
Continuous monitoring and archiving of background radiation levels in and around the nuclear installation is essential and the data would be of immense use during analysis of any untoward incidents. A portable Geiger Muller detector based autonomous gamma dose logger (AGDL) for environmental monitoring is indigenously designed and developed. The system operations are controlled by microcontroller (AT89S52) and the main features of the system are software data acquisition, real time LCD display of radiation level, data archiving at removable compact flash card. The complete system operates on 12 V battery backed up by solar panel and hence the system ismore » totally portable and ideal for field use. The system has been calibrated with Co-60 source (8.1 MBq) at various source-detector distances. The system is field tested and performance evaluation is carried out. This paper covers the design considerations of the hardware, software architecture of the system along with details of the front-end operation of the autonomous gamma dose logger and the data file formats. The data gathered during field testing and inter comparison with GammaTRACER are also presented in the paper. AGDL has shown excellent correlation with energy fluence monitor tuned to identify {sup 41}Ar, proving its utility for real-time plume tracking and source term estimation.« less
Phillips, Nathan; Bond, Barbara J.
1999-07-01
To record photosynthetically active radiation (PAR) simultaneously at a number of points throughout a forest canopy, we developed a simple, inexpensive (< $10 US) current-to-voltage converter that processes the current generated by a photodiode radiation sensor to a voltage range that is recordable with a miniature data logger. The converter, which weighs less than 75 g and has a volume of only 100 cm(3), is built around an ultra-low power OP-90 precision operational amplifier, which consumes less than 0.5 mA at 9 V when converting the output of a Li-Cor LI-190SA quantum sensor exposed to photosynthetically active radiation (PAR) of 2500 &mgr;mol m(-2) s(-1) or only 5 &mgr;A in low light. A small 9-V battery thus powers the amplifier for more than 1000 h of continuous operation. Correlations between photometer readings and voltage output from the current-to-voltage converter were high and linear at both high and low PAR. Sixteen Li-Cor LI-190SA quantum sensors each equipped with current-to-voltage converters and connected to a miniature data logger were deployed in the upper branches of a Panamanian tropical rainforest canopy. Each unit performed reliably during a one- or two-week evaluation.
Development of autonomous gamma dose logger for environmental monitoring
NASA Astrophysics Data System (ADS)
Jisha, N. V.; Krishnakumar, D. N.; Surya Prakash, G.; Kumari, Anju; Baskaran, R.; Venkatraman, B.
2012-03-01
Continuous monitoring and archiving of background radiation levels in and around the nuclear installation is essential and the data would be of immense use during analysis of any untoward incidents. A portable Geiger Muller detector based autonomous gamma dose logger (AGDL) for environmental monitoring is indigenously designed and developed. The system operations are controlled by microcontroller (AT89S52) and the main features of the system are software data acquisition, real time LCD display of radiation level, data archiving at removable compact flash card. The complete system operates on 12 V battery backed up by solar panel and hence the system is totally portable and ideal for field use. The system has been calibrated with Co-60 source (8.1 MBq) at various source-detector distances. The system is field tested and performance evaluation is carried out. This paper covers the design considerations of the hardware, software architecture of the system along with details of the front-end operation of the autonomous gamma dose logger and the data file formats. The data gathered during field testing and inter comparison with GammaTRACER are also presented in the paper. AGDL has shown excellent correlation with energy fluence monitor tuned to identify 41Ar, proving its utility for real-time plume tracking and source term estimation.
LaZerte, Stefanie E; Reudink, Matthew W; Otter, Ken A; Kusack, Jackson; Bailey, Jacob M; Woolverton, Austin; Paetkau, Mark; de Jong, Adriaan; Hill, David J
2017-10-01
Radio frequency identification (RFID) provides a simple and inexpensive approach for examining the movements of tagged animals, which can provide information on species behavior and ecology, such as habitat/resource use and social interactions. In addition, tracking animal movements is appealing to naturalists, citizen scientists, and the general public and thus represents a tool for public engagement in science and science education. Although a useful tool, the large amount of data collected using RFID may quickly become overwhelming. Here, we present an R package (feedr) we have developed for loading, transforming, and visualizing time-stamped, georeferenced data, such as RFID data collected from static logger stations. Using our package, data can be transformed from raw RFID data to visits, presence (regular detections by a logger over time), movements between loggers, displacements, and activity patterns. In addition, we provide several conversion functions to allow users to format data for use in functions from other complementary R packages. Data can also be visualized through static or interactive maps or as animations over time. To increase accessibility, data can be transformed and visualized either through R directly, or through the companion site: http://animalnexus.ca, an online, user-friendly, R-based Shiny Web application. This system can be used by professional and citizen scientists alike to view and study animal movements. We have designed this package to be flexible and to be able to handle data collected from other stationary sources (e.g., hair traps, static very high frequency (VHF) telemetry loggers, observations of marked individuals in colonies or staging sites), and we hope this framework will become a meeting point for science, education, and community awareness of the movements of animals. We aim to inspire citizen engagement while simultaneously enabling robust scientific analysis.
Development of software for geodynamic processes monitoring system
NASA Astrophysics Data System (ADS)
Kabanov, M. M.; Kapustin, S. N.; Gordeev, V. F.; Botygin, I. A.; Tartakovsky, V. A.
2017-11-01
This article justifies the usage of natural pulsed electromagnetic Earth's noises logging method for mapping anomalies of strain-stress state of Earth's crust. The methods and technologies for gathering, processing and systematization of data gathered by ground multi-channel geophysical loggers for monitoring geomagnetic situation have been experimentally tested, and software had been developed. The data was consolidated in a network storage and can be accessed without using any specialized client software. The article proposes ways to distinguish global and regional small-scale time-space variations of Earth's natural electromagnetic field. For research purposes, the software provides a way to export data for any given period of time for any loggers and displays measurement data charts for selected set of stations.
NASA Astrophysics Data System (ADS)
Rogers, Daniel M.
The research is aimed to evaluate thermal spray coatings to address material issues in supercritical and ultra-supercritical Rankine cycles. The primary purpose of the research is to test, evaluate, and eventually implement a coating to improve corrosion resistance and increase efficiency of coal fired power plants. The research is performed as part of a comprehensive project to evaluate the ability of titanium, titanium carbide, or titanium diboride powders to provide fireside corrosion resistance in supercritical and ultra-supercritical steam boilers, specifically, coal driven boilers in Illinois that must utilize high sulfur and high chlorine content coal. [1] The powder coatings that were tested are nano-sized titanium carbide (TiC) and titanium di-boride (TiB2) powders that were synthesized by a patented process at Southern Illinois University. The powders were then sent to Gas Technology Institute in Chicago to coat steel coupons by HVOF (High Velocity Oxy-Fuel) thermal spray technique. The powders were coated on an austenitic 304H stainless steel substrate which is commonly found in high temperature boilers, pipelines, and heat exchangers. The samples then went through various tests for various lengths of time under subcritical, supercritical, and ultra-supercritical conditions. The samples were examined using a scanning electron microscope and x-ray diffraction techniques to study microstructural changes and then determined which coating performed best.
Zhan, Yaoyao; Hu, Wanbin; Zhang, Weijie; Liu, Minbo; Duan, Lizhu; Huang, Xianya; Chang, Yaqing; Li, Cong
2016-11-15
The impact of CO 2 -driven ocean acidification(OA) on early development and calcification in the sea urchin Strongylocentrotus intermedius cultured in northern Yellow Sea was investigated by comparing fertilization success, early cleavage rate, hatching rate of blastulae, larvae survival rate at 70h post-fertilization, larval morphology and calcification under present natural seawater condition (pH=8.00±0.03) and three laboratory-controlled acidified conditions (OA 1 , △pH=-0.3units; OA 2 , △pH=-0.4units; OA 3 , △pH=-0.5units) projected by IPCC for 2100. Results showed that pH decline had no effect on the overall fertilization, however, with decreased pH, delayed early embryonic cleavage, reduced hatching rate of blastulae and four-armed larvae survival rate at 70h post-fertilization, impaired larval symmetry, shortened larval spicules, and corrosion spicule structure were observed in all OA-treated groups as compared to control, which indicated that CO 2 -driven OA affected early development and calcification in S. intermedius negatively. Copyright © 2016 Elsevier Ltd. All rights reserved.
Shaffer, Scott A.; Clatterbuck, Corey A.; Kelsey, Emma C.; Naiman, Alex D.; Young, Lindsay C.; VanderWerf, Eric A.; Warzybok, Pete; Bradley, Russell; Jahncke, Jaime; Bower, Geoff C.
2014-01-01
Egg turning is unique to birds and critical for embryonic development in most avian species. Technology that can measure changes in egg orientation and temperature at fine temporal scales (1 Hz) was neither readily available nor small enough to fit into artificial eggs until recently. Here we show the utility of novel miniature data loggers equipped with 3-axis (i.e., triaxial) accelerometers, magnetometers, and a temperature thermistor to study egg turning behavior in free-ranging birds. Artificial eggs containing egg loggers were deployed in the nests of three seabird species for 1–7 days of continuous monitoring. These species (1) turned their eggs more frequently (up to 6.5 turns h−1) than previously reported for other species, but angular changes were often small (1–10° most common), (2) displayed similar mean turning rates (ca. 2 turns h−1) despite major differences in reproductive ecology, and (3) demonstrated distinct diurnal cycling in egg temperatures that varied between 1.4 and 2.4°C. These novel egg loggers revealed high-resolution, three-dimensional egg turning behavior heretofore never measured in wild birds. This new form of biotechnology has broad applicability for addressing fundamental questions in avian breeding ecology, life history, and development, and can be used as a tool to monitor birds that are sensitive to disturbance while breeding. PMID:24887441
Godfrey, A; Culhane, K M; Lyons, G M
2007-10-01
The aim of this study was to assess the accuracy of the 'activPAL Professional' physical activity logger by comparing its output to that of a proven discrete accelerometer-based activity monitor during extended measurements on healthy subjects while performing activities of daily living (ADL). Ten healthy adults, with unrestricted mobility, wore both the activPAL and the discrete dual accelerometer (Analog Devices ADXL202)-based activity monitor that recorded in synchronization with each other. The accelerometer derived data were then compared to that generated by the activPAL and a complete statistical and error analysis was performed using a Matlab program. This program determined trunk and thigh inclination angles to distinguish between sitting/lying, standing and stepping for the discrete accelerometer device and amount of time spent on each activity. Analysis was performed on a second-by-second basis and then categorized at 15s intervals in direct comparison with the activPAL generated data. Of the total time monitored (approximately 60 h) the detection accuracies for static and dynamic activities were approximately 98%. In a population of healthy adults, the data obtained from the activPAL Professional physical activity logger for both static and dynamic activities showed a close match to a proven discrete accelerometer data with an offset of approximately 2% between the two systems.
On the frequency response of a Wenglor particle-counting system for aeolian transport measurements
NASA Astrophysics Data System (ADS)
Bauer, Bernard O.; Davidson-Arnott, Robin G. D.; Hilton, Michael J.; Fraser, Douglas
2018-06-01
A commonly deployed particle-counting system for aeolian saltation flux, consisting of a Wenglor fork sensor and an Onset Hobo Pulse Input Adapter linked to an Onset Hobo Energy Logger Pro data logger, was tested for frequency response. The Wenglor fork sensor is an optical gate device that has very fast switching capacity that can accommodate the time of flight of saltating sand particles through the sensing volume with the exception of very fine sand or silt and very quickly moving particles. The Pulse Input Adapter, in contrast, imposes limitations on the frequency response of the system. The manufacturer of the pulse adapter specifies an upper limit of 120 Hz, although bench tests with an electronic pulse generator indicate that the frequency response of the Pulse Input Adapter, in isolation, is excellent up to 3000 Hz, with only small error (less than 1.6%) due to under-counting during data transfer intervals. A mechanical test of the integrated system (fork sensor, pulse input adapter, and data logger) demonstrates excellent performance up to about 700 Hz (less than 2% error), but significant under-counting above 1000 Hz for unknown reasons. This specific particle-counting system therefore has a frequency response that is well suited for investigation of the dynamics of aeolian saltation as typically encountered in most field conditions on coastal beaches with the exception of extreme wind events and very small particle sizes.
Design and Deployment of a General Purpose, Open Source LoRa to Wi-Fi Hub and Data Logger
NASA Astrophysics Data System (ADS)
DeBell, T. C.; Udell, C.; Kwon, M.; Selker, J. S.; Lopez Alcala, J. M.
2017-12-01
Methods and technologies facilitating internet connectivity and near-real-time status updates for in site environmental sensor data are of increasing interest in Earth Science. However, Open Source, Do-It-Yourself technologies that enable plug and play functionality for web-connected sensors and devices remain largely inaccessible for typical researchers in our community. The Openly Published Environmental Sensing Lab at Oregon State University (OPEnS Lab) constructed an Open Source 900 MHz Long Range Radio (LoRa) receiver hub with SD card data logger, Ethernet and Wi-Fi shield, and 3D printed enclosure that dynamically uploads transmissions from multiple wirelessly-connected environmental sensing devices. Data transmissions may be received from devices up to 20km away. The hub time-stamps, saves to SD card, and uploads all transmissions to a Google Drive spreadsheet to be accessed in near-real-time by researchers and GeoVisualization applications (such as Arc GIS) for access, visualization, and analysis. This research expands the possibilities of scientific observation of our Earth, transforming the technology, methods, and culture by combining open-source development and cutting edge technology. This poster details our methods and evaluates the application of using 3D printing, Arduino Integrated Development Environment (IDE), Adafruit's Open-Hardware Feather development boards, and the WIZNET5500 Ethernet shield for designing this open-source, general purpose LoRa to Wi-Fi data logger.
40 CFR 92.127 - Emission measurement accuracy.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Emission measurement accuracy. (a) Good engineering practice dictates that exhaust emission sample analyzer... resolution read-out systems such as computers, data loggers, etc., can provide sufficient accuracy and...
40 CFR 92.127 - Emission measurement accuracy.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Emission measurement accuracy. (a) Good engineering practice dictates that exhaust emission sample analyzer... resolution read-out systems such as computers, data loggers, etc., can provide sufficient accuracy and...
40 CFR 92.127 - Emission measurement accuracy.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Emission measurement accuracy. (a) Good engineering practice dictates that exhaust emission sample analyzer... resolution read-out systems such as computers, data loggers, etc., can provide sufficient accuracy and...
40 CFR 92.127 - Emission measurement accuracy.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Emission measurement accuracy. (a) Good engineering practice dictates that exhaust emission sample analyzer... resolution read-out systems such as computers, data loggers, etc., can provide sufficient accuracy and...
40 CFR 92.127 - Emission measurement accuracy.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Emission measurement accuracy. (a) Good engineering practice dictates that exhaust emission sample analyzer... resolution read-out systems such as computers, data loggers, etc., can provide sufficient accuracy and...
Reconstructing a hydrogen-driven microbial metabolic network in Opalinus Clay rock.
Bagnoud, Alexandre; Chourey, Karuna; Hettich, Robert L; de Bruijn, Ino; Andersson, Anders F; Leupin, Olivier X; Schwyn, Bernhard; Bernier-Latmani, Rizlan
2016-10-14
The Opalinus Clay formation will host geological nuclear waste repositories in Switzerland. It is expected that gas pressure will build-up due to hydrogen production from steel corrosion, jeopardizing the integrity of the engineered barriers. In an in situ experiment located in the Mont Terri Underground Rock Laboratory, we demonstrate that hydrogen is consumed by microorganisms, fuelling a microbial community. Metagenomic binning and metaproteomic analysis of this deep subsurface community reveals a carbon cycle driven by autotrophic hydrogen oxidizers belonging to novel genera. Necromass is then processed by fermenters, followed by complete oxidation to carbon dioxide by heterotrophic sulfate-reducing bacteria, which closes the cycle. This microbial metabolic web can be integrated in the design of geological repositories to reduce pressure build-up. This study shows that Opalinus Clay harbours the potential for chemolithoautotrophic-based system, and provides a model of microbial carbon cycle in deep subsurface environments where hydrogen and sulfate are present.
Reconstructing a hydrogen-driven microbial metabolic network in Opalinus Clay rock
Bagnoud, Alexandre; Chourey, Karuna; Hettich, Robert L.; de Bruijn, Ino; Andersson, Anders F.; Leupin, Olivier X.; Schwyn, Bernhard; Bernier-Latmani, Rizlan
2016-01-01
The Opalinus Clay formation will host geological nuclear waste repositories in Switzerland. It is expected that gas pressure will build-up due to hydrogen production from steel corrosion, jeopardizing the integrity of the engineered barriers. In an in situ experiment located in the Mont Terri Underground Rock Laboratory, we demonstrate that hydrogen is consumed by microorganisms, fuelling a microbial community. Metagenomic binning and metaproteomic analysis of this deep subsurface community reveals a carbon cycle driven by autotrophic hydrogen oxidizers belonging to novel genera. Necromass is then processed by fermenters, followed by complete oxidation to carbon dioxide by heterotrophic sulfate-reducing bacteria, which closes the cycle. This microbial metabolic web can be integrated in the design of geological repositories to reduce pressure build-up. This study shows that Opalinus Clay harbours the potential for chemolithoautotrophic-based system, and provides a model of microbial carbon cycle in deep subsurface environments where hydrogen and sulfate are present. PMID:27739431
NASA Astrophysics Data System (ADS)
Gordeev, V. F.; Malyshkov, S. Yu.; Botygin, I. A.; Sherstnev, V. S.; Sherstneva, A. I.
2017-11-01
The general trend of modern ecological geophysics is changing priorities towards rapid assessment, management and prediction of ecological and engineering soil stability as well as developing brand new geophysical technologies. The article describes researches conducted by using multi-canal geophysical logger MGR-01 (developed by IMCES SB RAS), which allows to measure flux density of very low-frequency electromagnetic radiation. It is shown that natural pulsed electromagnetic fields of the earthen lithosphere can be a source of new information on Earth's crust and processes in it, including earthquakes. The device is intended for logging electromagnetic processes in Earth's crust, geophysical exploration, finding structural and lithological inhomogeneities, monitoring the geodynamic movement of Earth's crust, express assessment of seismic hazards. The data is gathered automatically from observation point network in Siberia
Flight experience with lightweight, low-power miniaturized instrumentation systems
NASA Technical Reports Server (NTRS)
Hamory, Philip J.; Murray, James E.
1992-01-01
Engineers at the NASA Dryden Flight Research Facility (NASA-Dryden) have conducted two flight research programs with lightweight, low-power miniaturized instrumentation systems built around commercial data loggers. One program quantified the performance of a radio-controlled model airplane. The other program was a laminar boundary-layer transition experiment on a manned sailplane. The purpose of this paper is to report NASA-Dryden personnel's flight experience with the miniaturized instrumentation systems used on these two programs. The paper will describe the data loggers, the sensors, and the hardware and software developed to complete the systems. The paper also describes how the systems were used and covers the challenges encountered to make them work. Examples of raw data and derived results will be shown as well. Finally, future plans for these systems will be discussed.
Development and testing of a tensiologger: a tensiometer with a built-in datalogger
NASA Astrophysics Data System (ADS)
Tuts, Valentijn; Ronchi, Benedicta; Diels, Jan
2014-05-01
Water-filled tensiometers are widely used for measuring matric potential in the range between 0 and approximately -90kPa in soils. When placed in variably-saturated soil horizons, they correctly measure the pressure head both in unsaturated and saturated conditions. Modern tensiometers consist of a porous ceramic cup filled with water that is connected to a pressure transducer. Tensiometers are commercially available in different models, and can be logged with data loggers. Logging requires either cabling to connect the tensiometers to a data logger, or a wireless connection. Cables hamper field operations and can be unpractical because of the distances involved. Commercially available systems with wireless data communication with a central datalogger do not come cheap. We therefore developed a simple water-filled tensiometer with a build-in datalogger, which we called a tensiologger. The tensiologger is assembled using a porous ceramic cup (Al2O3 sinter material with bubble point > 15 bar, UMS GmbH Munich, Germany) filled with degassed demineralised water for transferring the pressure head to the pressure transducer. This cup is screwed onto a small housing with a capsulated logger circuit consisting of a pressure transducer, a temperature sensor for temperature measurement and for temperature correction of the pressure transducer, a memory for 32k measurements, and a microcontroller for logging the data. This loggercircuit is screwed onto an extension tube of 25 mm diameter that contains a replaceable battery and an optical interface at the top (extending from the soil surface). The data can be retrieved from the logger by means of a readout unit that is placed over the optical interface. This readout unit is connected to a USB port of a portable PC with logger software developed in Visual Basic. The cost of all parts including the printed circuit board is 220€ (excluding labour cost for making screw connections and assembling). The tensiologger was tested over a 8-month period at a grassland site in Blegny, Belgium. We installed tensiologgers at three different locations along a slope and at 15, 45, and 75 cm depth. At the lowest topographic location, we measured groundwater levels with a diver, which allowed us to know when soil is saturated. During or after rainfall events, tension peaks were detected at all depths with a little retardation along the profile, and positive pressure head values were measured as the soil became saturated. Higher on the slope, where drilling problems impede piezometer installation, positive tensions were measured sporadically at 75 cm and 45 cm depth. In dry periods, air bubbles developed in the cups of the shallow tensiologgers, and so cups had to be refilled with degassed water.
Real-time Remote Data Online For Norris Geyser Basin in Yellowstone National Park
NASA Astrophysics Data System (ADS)
Perry, J. E.; Lowenstern, J. B.; Clor, L.; Cervelli, P. F.; Allen, S. T.; Heasler, H.; Moloney, T.
2010-12-01
Perry, John, Lowenstern, Jacob, Cervelli, Peter, Clor, Laura, Heasler, Henry, Allen, Scott, Moloney, Tim During June 2010, ten 900MHz wireless temperature data loggers (nodes) were installed around the Norris Geyser Basin to monitor geothermal features, streams and soil temperatures. The loggers can provide near real-time updates on temperature variations within 0.2 deg C due to hydrothermal discharges or subsurface fluid migration. Each sensor node is programmed to measure the temperature every two minutes and automatically upload data to the base station computer daily. The hardware consists of a waterproof case containing an M5 logger (made by Marathon Products, Inc.®) with internal memory, lithium D-cell batteries and a 900 MHz, 1-W-transceiver and 5 meter long Teflon-coated probe with a thermistor sensor. Tethered stub or panel antennas are oriented to optimize signal strength to the base station near the Norris Museum. A 0.61 meter-long base-station antenna located 10m high provides signal to the furthest node over 850 meters away with most being “line-of-sight”. A 20-meter coaxial cable and lightning grounding wire connects the base-station antenna to an Ethernet-radio connected to the YNP local-area network. A server located 26-km north at Mammoth Hot Springs requests data at regular intervals (normally daily), archives the information, and then sends it to the USGS for further archiving and internet distribution. During periods of unusual hydrothermal behavior, data can be requested as needed, and it is possible to set user-programmable alarm limits for notification. The RF network is designed to monitor changes from three different sub-basins at Norris (Gray Lakes, Steamboat-Echinus and Porcelain Basin), the main Tantalus Creek drainage, and five individual thermal features (Constant, Porkchop, Steamboat and Echinus Geysers, and Opalescent Spring). The logger installed in Nuphar Lake provides ambient temperatures controlled solely by local meteorological conditions. Soil temperature is measured near Vixen Geyser. The system will permit land managers, scientists and the public to keep track of changes to the hydrothermal system, including geyser eruptions, periodic basin-wide disturbances, or fluid-release events that may accompany or follow seismic activity.
Microprocessors: Laboratory Simulation of Industrial Control Applications.
ERIC Educational Resources Information Center
Gedeon, David V.
1981-01-01
Describes a course to make technical managers more aware of computer technology and how data loggers, programmable controllers, and larger computer systems interact in a hierarchical configuration of manufacturing process control. (SK)
Livestock Grazing as a Driver of Vernal Pool Ecohydrology
NASA Astrophysics Data System (ADS)
Michaels, J.; McCarten, N. F.
2017-12-01
Vernal pools are seasonal wetlands that host rare plant communities of high conservation priority. Plant community composition is largely driven by pool hydroperiod. A previous study found that vernal pools grazed by livestock had longer hydroperiods compared with pools excluded from grazing for 10 years, and suggests that livestock grazing can be used to protect plant diversity. It is important to assess whether observed differences are due to the grazing or due to water balance variables including upland discharge into or out of the pools since no a priori measurements were made of the hydrology prior to grazing. To address this question, in 2016 we compared 15 pools that have been grazed continuously and 15 pools that have been fenced off for over 40 years at a site in Sacramento County. We paired pools based on abiotic characteristics (size, shape, slope, soil type) to minimize natural variation. We sampled vegetation and water depth using Solinst level loggers. We found that plant diversity and average hydroperiod was significantly higher in the grazed pools. We are currently measuring groundwater connectivity and upland inputs in order to compare the relative strength of livestock grazing as a driver of hydroperiod to these other drivers.
LCLS-II CRYOMODULE TRANSPORT SYSTEM TESTING
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huque, Naeem; Daly, Edward F.; McGee, Michael W.
The Cryomodules (CM) for the Linear Coherent Light Source II (LCLS-II) will be shipped to SLAC (Menlo Park, California) from JLab (Newport News, Virginia) and FNAL (Batavia, Illinois). A transportation system has been designed and built to safely transport the CMs over the road. It uses an array of helical isolator springs to attenuate shocks on the CM to below 1.5g in all directions. The system rides on trailers equipped with Air-Ride suspension, which attenuates vibration loads. The prototype LCLS-II CM (pCM) was driven 750 miles to test the transport system; shock loggers recorded the shock attenuation on the pCMmore » and vacuum gauges were used to detect any compromises in beamline vacuum. Alignment measurements were taken before and after the trip to check whether cavity positions had shifted beyond the ± 0.2mm spec. Passband frequencies and cavity gradients were measured at 2K at the Cryomodule Test Facility (CMTF) at JLab to identify any degradation of CM performance after transportation. The transport system was found to have safely carried the CM and is cleared to begin shipments from JLab and FNAL to SLAC.« less
Development of Ocean-Bottom Seismograph in Taiwan
NASA Astrophysics Data System (ADS)
Chang, H.; Jang, J. P.; Chen, P.; Lin, C. R.; Kuo, B. Y.; Wang, C. C.; Kim, K. H.; Lin, P. P.
2016-12-01
Yardbird-20s, one type of Ocean-Bottom Seismograph (OBS), is fabricated by Taiwan Ocean Research Institute (TORI), the Institute of Earth Science of Academia Sinica and the Institute of Undersea Technology of the National Sun Yat-Sen University in Taiwan. Yardbirds can be deployed up to 5000m deep for up to 15 months. The total weight with anchor in the air is about 170Kg. The rising and sinking rate is about 0.8 m/s. We utilized ultra-low power micro control unit (MCU) and SD card to design a data logger. The sensors are three of 4.5Hz geophones that were extended the lower frequency response to 20 sec. The sensor module also includes the leveling system, which is design by dual-axis DC motor-driven module to level the vertical component to be less than 0.1 degree with respect to the gravity. Yardbirds have been successfully deployed and recovered in several research cruises in Taiwan and Korea. In this study, we'll also display the data quality and power spectral density (PSD) calculations, probability density function (PDF) plots and from the Yardbirds that deployed and recovered in the East Sea near sough-east of Korea.
The effects of time on the capacity of pipe piles in dense marine sand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chow, F.C.; Jardine, R.J.; Brucy, F.
Investigations into pile behavior in dense marine sand have been performed by IFP and IC at Dunkirk, North France. In the most recent series of tests, strain-gauged, open-ended pipe piles, driven and statically load tested in 1989, were retested in 1994. Surprisingly large increases in shaft capacity were measured. The possible causes are evaluated in relation to previous case histories, laboratory soil tests, pile corrosion and new effective stress analyses developed using smaller, more intensively instrumented piles. The shaft capacities predicted by existing design methods are also assessed. 51 refs., 12 figs., 4 tabs.
76 FR 44306 - Endangered Species; File No. 16146
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-25
.... Of the 160, 20 also would be tagged with satellite tags and data loggers (epoxy attachments) and acoustic transmitters (epoxy or drill carapace and attach with wire). All 20 would not necessarily be...
Encourage student learning of hydraulic matters by the use of Arduino platform
NASA Astrophysics Data System (ADS)
Rodriguez Sinobas, Leonor; Granja García, Javier; Sánchez Calvo, Raúl
2014-05-01
Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for several purposes to anyone interested in creating interactive objects or environments. The hydraulic matters teach at the Agricultural Engineering School at the Technical University of Madrid deal with practical issues regarding the measurement of variables such as pressure, discharge, temperature and soil water content. Most of the data loggers available in the market for these variables at expensive and not always affordable. On the other hand, current students are eager to manage new technological devices thus, their skills could be oriented not only to the application of an electronic platform as Arduino to build low cost data loggers for different purposes, but to encourage their learning in the hydraulic matters improving their self esteem
Diving Simulation concerning Adélie Penguin
NASA Astrophysics Data System (ADS)
Ito, Shinichiro; Harada, Masanori
Penguins are sea birds that swim using lift and drag forces by flapping their wings like other birds. Although diving data can be obtained using a micro-data logger which has improved in recent years, all the necessary diving conditions for analysis cannot be acquired. In order to determine all these hard-to-get conditions, the posture and lift and drag forces of penguins were theoretically calculated by the technique used in the analysis of the optimal flight path of aircrafts. In this calculation, the actual depth and speed of the dive of an Adélie penguin (Pygoscelis adeliae) were utilized. Then, the calculation result and experimental data were compared, and found to be in good agreement. Thus, it is fully possible to determine the actual conditions of dive by this calculation, even those that cannot be acquired using a data logger.
de Jong, Carol; Field, Hume; Tagtag, Anson; Hughes, Tom; Dechmann, Dina; Jayme, Sarah; Epstein, Jonathan H; Epstein, Jonathan; Smith, Craig; Santos, Imelda; Catbagan, Davinio; Lim, Mundita; Benigno, Carolyn; Daszak, Peter; Newman, Scott
2013-01-01
Species of Old World fruit-bats (family Pteropodidae) have been identified as the natural hosts of a number of novel and highly pathogenic viruses threatening livestock and human health. We used GPS data loggers to record the nocturnal foraging movements of Acerodon jubatus, the Golden-crowned flying fox in the Philippines to better understand the landscape utilisation of this iconic species, with the dual objectives of pre-empting disease emergence and supporting conservation management. Data loggers were deployed on eight of 54 A. jubatus (two males and six females) captured near Subic Bay on the Philippine island of Luzon between 22 November and 2 December 2010. Bodyweight ranged from 730 g to 1002 g, translating to a weight burden of 3-4% of bodyweight. Six of the eight loggers yielded useful data over 2-10 days, showing variability in the nature and range of individual bat movements. The majority of foraging locations were in closed forest and most were remote from evident human activity. Forty-six discrete foraging locations and five previously unrecorded roost locations were identified. Our findings indicate that foraging is not a random event, with the majority of bats exhibiting repetitious foraging movements night-to-night, that apparently intact forest provides the primary foraging resource, and that known roost locations substantially underestimate the true number (and location) of roosts. Our initial findings support policy and decision-making across perspectives including landscape management, species conservation, and potentially disease emergence.
Castle, Kevin T.; Weller, Theodore J.; Cryan, Paul M.; Hein, Cris D.; Schirmacher, Michael R.
2015-01-01
1. Determining the detailed movements of individual animals often requires them to carry tracking devices, but tracking broad-scale movement of small bats (< 30g) has been limited by transmitter technology and long-term attachment methods. This limitation inhibits our understanding of bat dispersal and migration, particularly in the context of emerging conservation issues like fatalities at wind turbines and diseases. 2. We tested a novel method of attaching lightweight global positioning system (GPS) tags and geolocating data loggers to small bats. We used monofilament, synthetic, absorbable sutures to secure GPS tags and data loggers to the skin of anesthetized big brown bats (Eptesicus fuscus) in Colorado and hoary bats (Lasiurus cinereus) in California. 3. GPS tags and data loggers were sutured to 17 bats in this study. Three tagged bats were recaptured seven months after initial deployment, with tags still attached; none of these bats showed ill effects from the tag. No severe injuries were apparent upon recapture of 6 additional bats that carried tags up to 26 days after attachment, however one of the bats exhibited skin chafing. 4. Use of absorbable sutures to affix small tracking devices seems to be a safe, effective method for studying movements of bats over multiple months, although additional testing is warranted. This new attachment method has the potential to quickly advance our understanding of small bats, particularly as more-sophisticated miniature tracking devices (e.g., satellite tags) become available.
Castle, Kevin T; Weller, Theodore J; Cryan, Paul M; Hein, Cris D; Schirmacher, Michael R
2015-07-01
Determining the detailed movements of individual animals often requires them to carry tracking devices, but tracking broad-scale movement of small bats (<30 g) has been limited by transmitter technology and long-term attachment methods. This limitation inhibits our understanding of bat dispersal and migration, particularly in the context of emerging conservation issues such as fatalities at wind turbines and diseases. We tested a novel method of attaching lightweight global positioning system (GPS) tags and geolocating data loggers to small bats. We used monofilament, synthetic, absorbable sutures to secure GPS tags and data loggers to the skin of anesthetized big brown bats (Eptesicus fuscus) in Colorado and hoary bats (Lasiurus cinereus) in California. GPS tags and data loggers were sutured to 17 bats in this study. Three tagged bats were recaptured 7 months after initial deployment, with tags still attached; none of these bats showed ill effects from the tag. No severe injuries were apparent upon recapture of 6 additional bats that carried tags up to 26 days after attachment; however, one of the bats exhibited skin chafing. Use of absorbable sutures to affix small tracking devices seems to be a safe, effective method for studying movements of bats over multiple months, although additional testing is warranted. This new attachment method has the potential to quickly advance our understanding of small bats, particularly as more sophisticated miniature tracking devices (e.g., satellite tags) become available.
Is propensity to obesity associated with the diurnal pattern of core body temperature?
Hynd, P I; Czerwinski, V H; McWhorter, T J
2014-02-01
Obesity affects more than half a billion people worldwide, but the underlying causes remain unresolved. It has been proposed that propensity to obesity may be associated with differences between individuals in metabolic efficiency and in the energy used for homeothermy. It has also been suggested that obese-prone individuals differ in their responsiveness to circadian rhythms. We investigated both these hypotheses by measuring the core body temperature at regular and frequent intervals over a diurnal cycle, using indigestible temperature loggers in two breeds of canines known to differ in propensity to obesity, but prior to divergence in fatness. Greyhounds (obesity-resistant) and Labradors (obesity-prone) were fed indigestible temperature loggers. Gastrointestinal temperature was recorded at 10-min intervals for the period of transit of the logger. Diet, body condition score, activity level and environment were similar for both groups. Energy digestibility was also measured. The mean core body temperature in obesity-resistant dogs (38.27 °C) was slightly higher (P<0.001) than in obesity-prone dogs (38.18 °C) and the former had a greater variation (P<0.001) in 24h circadian core temperature. There were no differences in diet digestibility. Canines differing in propensity to obesity, but prior to its onset, differed little in mean core temperature, supporting similar findings in already-obese and lean humans. Obese-prone dogs were less variable in daily core temperature fluctuations, suggestive of a degree of circadian decoupling.
UAV Applications in Hydrology: A Case Study in Gökova Basin, Muğla, Turkey
NASA Astrophysics Data System (ADS)
Kurtulus, B.; Sağır, Ç.; Erdem, G.; Avşar; Kurtuluş, D. F.; Tunca, E.; Le Coz, M.; Razack, M.
2016-12-01
Adopting new technologies to hydrogeological studies is quite seldom at the present time. In the near future, successfully applications of Unmanned Air Vehicle (UAV) and small data logging system will be expected to show positive impact by encouraging the innovative designs and uses of these systems to monitor hydrosystem changes in local-to-regional ecosystems. Understanding of hydrosystem using these devices and the prediction of global/local change impacts on it has one of the highest scientific and socio-economic importance in Mediterranean zone. This study is a part of an ERANETMED project title as "Groundwater Resilience to Climate Change and High Pressure within an IWRM Approach". The main aim is to use of different types of drone and loggers equipped with visible/multispectral/thermal cameras for monitoring karstic springs, lakes, rivers etc... The advantages of this study are the ease of field data acquiring, fast and safe measurement process without making any harm to karstic springs by using hazardous materials and implement hi-tech instruments in hydrogeology studies. Therefore, in this study producing high resolution spatial and temporal hydrodynamic and physicochemical data of karst springs are collected by using drone and loggers. The preliminary results of drone images, logger data analysis and the possible application use of drones in hydrogeology domain will be presented in this study. In this regard, we would like to thank TUBITAK & ERANETMED (Project No: 115Y843) and the project members.
NASA Astrophysics Data System (ADS)
Bates, Alan
2015-12-01
Instruments or digital meters with data values visible on a seven-segment display can easily be found in the physics lab. Examples include multimeters, sound level meters, Geiger-Müller counters and electromagnetic field meters, where the display is used to show numerical data. Such instruments, without the ability to connect to computers or data loggers, can measure and display data at a particular instant in time. The user should be present to read the display and to record the data. Unlike these digital meters, the sensor-data logger system has the advantage of automatically measuring and recording data at selectable sample rates over a desired sample time. The process of adding data logging features to a digital meter with a seven-segment display can be achieved with Seven Segment Optical Character Recognition (SSOCR) software. One might ask, why not just purchase a field meter with data logging features? They are relatively inexpensive, reliable, available online, and can be delivered within a few days. But then there is the challenge of making your own instrument, the excitement of implementing a design, the pleasure of experiencing an entire process from concept to product, and the satisfaction of avoiding costs by taking advantage of available technology. This experiment makes use of an electromagnetic field meter with a seven-segment liquid crystal display to measure background electromagnetic field intensity. Images of the meter display are automatically captured with a camera and analyzed using SSOCR to produce a text file containing meter display values.
Mashburn, Douglas N.; Stevens, Richard H.; Woodall, Harold C.
1977-01-01
This invention comprises a rotatable annular probe-positioner which carries at least one radially disposed sensing probe, such as a Pitot tube having a right-angled tip. The positioner can be coaxially and rotatably mounted within a compressor casing or the like and then actuated to orient the sensing probe as required to make measurements at selected stations in the annulus between the positioner and compressor casing. The positioner can be actuated to (a) selectively move the probe along its own axis, (b) adjust the yaw angle of the right-angled probe tip, and (c) revolve the probe about the axis common to the positioner and casing. A cam plate engages a cam-follower portion of the probe and normally rotates with the positioner. The positioner includes a first-motor-driven ring gear which effects slidable movement of the probe by rotating the positioner at a time when an external pneumatic cylinder is actuated to engage the cam plate and hold it stationary. When the pneumatic cylinder is not actuated, this ring gear can be driven to revolve the positioner and thus the probe to a desired circumferential location about the above-mentioned common axis. A second motor-driven ring gear included in the positioner can be driven to rotate the probe about its axis, thus adjusting the yaw angle of the probe tip. The positioner can be used in highly corrosive atmosphere, such as gaseous uranium hexafluoride.
Measuring and mapping rock wall permafrost across Norway
NASA Astrophysics Data System (ADS)
Magnin, Florence; Etzelmuller, Bernd; Hilger, Paula; Westermann, Sebastian; Isaksen, Ketil; Hermans, Reginald
2017-04-01
The investigation of rock wall permafrost is of high relevance for geohazards assessment and for understanding cold-climate landscape evolution since its changes over time can cause slope instability and trigger rock falls. The destabilization of steep slopes is a serious threat to human activities and lives in Norway, especially because most of rock walls lie directly above houses, infrastructures and large water bodies with potential of high-energy displacement waves. Rock wall permafrost has been investigated since the early 2010s in alpine massifs of western Norway thanks to the CryoLINK project (2008-2011). The CryoWALL project (2015-2019) aims at extending this preliminary study to the nation-wide scale. It consists in systematic measurements of rock surface temperature (RST) in order model and to map the spatial distribution of rock wall permafrost. In between August 2015 and August 2016, 20 RST loggers (Geoprecision mini data loggers, accuracy ± 0.1°C, precision 0.01°C, sensors PT1000) were installed at 10 cm depth of 7 selected sites. These loggers are distributed along a latitudinal transect (from 60°50'N to 69°46'N), cover various elevations and sun-exposures, and are completed by 4 other loggers installed in Jotunheimen in 2009 and 2010. The RST time series are used for (a) characterizing the distribution of rock wall permafrost across Norway, (b) running steady-state and transient numerical models of rock wall permafrost at selected sites, and to (c) calibrate a general linear regression model that will be used to (d) predict the spatial distribution of rock wall permafrost at the national scale. In this communication we will introduce the RST measurement installations and sites, as well as the first RST records that encompass 6 years of continuous measurements in Jotunheimen, and 1 year of record for 13 other loggers. The preliminary analysis shows that RST differs by 3°C between N and S faces in Southern Norway, with mean annual RST as low as -1.9°C at 1700 m a.s.l in a N face (Nordfjord, Sogn of Fjordane) during the measurement year which was about 0.8°C above normal (1981-2010). In Northern Norway, the RST difference between N and S faces is rather around 1.5°C due to the midnight sun and polar night effects, inducing similar RST in both aspects during December, January, May and June. Negative mean annual RST is found as low as 1200 m a.s.l in S-exposed faces (Kåfjorden, Troms) during the measurement year which was 1.1°C above normal in this area. The ice and snow coating the rock faces during winter appears as a significant warming factor that can raise the mean annual RST up to at least 1°C compared to bare rock conditions. This first data set is shown to be of high relevance for predictive modelling.
Exploring Quadratic Functions with Logger "Pro"
ERIC Educational Resources Information Center
Pope, Derek
2018-01-01
The author shares the lesson that he used to introduce the quadratic unit to students in an extended second-year algebra class, demonstrate why it was appropriate for his struggling learners, and discuss possible future modifications to this lesson.
Fabrication of the Appalachian Thinner
Cleveland J. Biller
1982-01-01
The Appalachian Thinner, a prototype cable yarder, has proven capable of harvesting timber on steep slopes. Details of the fabrication of the prototype yarder are presented. An Appalachian Thinner can be built economically in a typical logger's repair shop.
Iowa Saw-Log Production and Sawmill Industry, 1969
James E. Blyth
1972-01-01
Iowa loggers harvested nearly 47 million board feet of saw logs in 1969. Leading species were soft maple, elm, red oak, and cottonwood. Three-fifths of the wood residue generated at 63 Iowa sawmills was not used.
A portable smoking pattern recorder.
Creighton, D E; Noble, M J; Whewell, R T
1979-01-01
An instrument has been developed which can be used to record the smoking patterns of human smokers in almost any location. The smoker is required to smoke the cigarette through an orifice plate cigarette holder connected to the recorder. The smoking pattern data are recorded onto a standard audio cassette as pressure and flow signals together with timing impulses and speech. The instrument is battery powered and can be built into a small brief case. The four channels of data are decoded on a separate instrument, which uses the timing signals to synchronise a data logger, thus making the whole system independent of tape speed errors. The speech channel is used to identify the smoker, cigarette, location, etc. Comparisons have been made of the performance of the portable recorder and a laboratory smoking analyser and data logger. It was found that data decoded from the portable recorder are generally within 1% of the values recorded directly on the laboratory instrument.
NASA Astrophysics Data System (ADS)
Timi, Purnota Hannan; Shermin, Saima; Rahman, Asifur
2017-06-01
Flight data recorder is one of the most important sources of flight data in event of aviation disaster which records a wide range of flight parameters including altitude, airspeed, heading etc. and also helps monitoring and analyzing aircraft performance. Cockpit voice recorder records radio microphone transmissions and sounds in the cockpit. These devices help to find out and understand the root causes of aircraft crashes and help building better aircraft systems and technical solutions to prevent similar type of crashes in future, which lead to improvement in safety of aircrafts and passengers. There are other devices also which enhance the aircraft safety and assists in emergency or catastrophic situations. This paper discusses the concept of Flight Data Recorder (FDR), Cockpit Voice Recorder (CVR), Underwater Locator Beacon (ULB), Data logger and flarm-collision avoidance system for aircraft and their applications in aviation.
Merello, Paloma; García-Diego, Fernando-Juan; Zarzo, Manuel
2012-11-28
Ariadne's house, located at the city center of ancient Pompeii, is of great archaeological value due to the fresco paintings decorating several rooms. In order to assess the risks for long-term conservation affecting the valuable mural paintings, 26 temperature data-loggers and 26 relative humidity data-loggers were located in four rooms of the house for the monitoring of ambient conditions. Data recorded during 372 days were analyzed by means of graphical descriptive methods and analysis of variance (ANOVA). Results revealed an effect of the roof type and number of walls of the room. Excessive temperatures were observed during the summer in rooms covered with transparent roofs, and corrective actions were taken. Moreover, higher humidity values were recorded by sensors on the floor level. The present work provides guidelines about the type, number, calibration and position of thermohygrometric sensors recommended for the microclimate monitoring of mural paintings in outdoor or semi-confined environments.
Data-acquisition system for environmental monitoring aboard a twin-engined aircraft
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tichler, J.; Bernstein, H.; Brown, R.M.
A number of experimental platforms have been used in support of the Multistate Atmospheric Power Production Study (MAP3S) and the Coastal Meteorology programs at Brookhaven National Laboratory. These platforms include a twin-engine Britten Norman Islander aircraft, a motorized van, a variety of boats and temporary enclosures set up in the field. Each platform carried a data logger consisting of a multiplexer, an analog to digital (A/D) converter and a four track endless loop magnetic tape for data storage. In recent years it has become increasingly evident that the data loggers in use were no longer adequate. Since the aircraft providedmore » the most constraints on the data acquisition system as well as being the most important research platform, a data system was designed for that platform with the secondary goal that the system would serve as a prototype for systems to be used on other platforms.« less
Towards a Community Environmental Observation Network
NASA Astrophysics Data System (ADS)
Mertl, Stefan; Lettenbichler, Anton
2014-05-01
The Community Environmental Observation Network (CEON) is dedicated to the development of a free sensor network to collect and distribute environmental data (e.g. ground shaking, climate parameters). The data collection will be done with contributions from citizens, research institutions and public authorities like communities or schools. This will lead to a large freely available data base which can be used for public information, research, the arts,..... To start a free sensor network, the most important step is to provide easy access to free data collection and -distribution tools. The initial aims of the project CEON are dedicated to the development of these tools. A high quality data logger based on open hardware and free software is developed and a software suite of already existing free software for near-real time data communication and data distribution over the Internet will be assembled. Foremost, the development focuses on the collection of data related to the deformation of the earth (such as ground shaking, surface displacement of mass movements and glaciers) and the collection of climate data. The extent to other measurements will be considered in the design. The data logger is built using open hardware prototyping platforms like BeagleBone Black and Arduino. Main features of the data logger are: a 24Bit analog-to-digital converter; a GPS module for time reference and positioning; wireless mesh networking using Optimized Link State Routing; near real-time data transmission and communication; and near real-time differential GNSS positioning using the RTKLIB software. The project CEON is supported by the Internet Foundation Austria (IPA) within the NetIdee 2013 call.
Wildlife contact analysis: Emerging methods, questions, and challenges
Cross, Paul C.; Creech, Tyler G.; Ebinger, Michael R.; Heisey, Dennis M.; Irvine, Kathryn M.; Creel, Scott
2012-01-01
Recent technological advances, such as proximity loggers, allow researchers to collect complete interaction histories, day and night, among sampled individuals over several months to years. Social network analyses are an obvious approach to analyzing interaction data because of their flexibility for fitting many different social structures as well as the ability to assess both direct contacts and indirect associations via intermediaries. For many network properties, however, it is not clear whether estimates based upon a sample of the network are reflective of the entire network. In wildlife applications, networks may be poorly sampled and boundary effects will be common. We present an alternative approach that utilizes a hierarchical modeling framework to assess the individual, dyadic, and environmental factors contributing to variation in the interaction rates and allows us to estimate the underlying process variation in each. In a disease control context, this approach will allow managers to focus efforts on those types of individuals and environments that contribute the most toward super-spreading events. We account for the sampling distribution of proximity loggers and the non-independence of contacts among groups by only using contact data within a group during days when the group membership of proximity loggers was known. This allows us to separate the two mechanisms responsible for a pair not contacting one another: they were not in the same group or they were in the same group but did not come within the specified contact distance. We illustrate our approach with an example dataset of female elk from northwestern Wyoming and conclude with a number of important future research directions.
O'Neill, C J; Bishop-Hurley, G J; Williams, P J; Reid, D J; Swain, D L
2014-12-10
Reproductive efficiency is an important determinant of profitable cattle breeding systems and the success of assisted reproductive techniques (ART) in wildlife conservation programs. Methods of estrous detection used in intensive beef and dairy cattle systems lack accuracy and remain the single biggest issue for improvement of reproductive rates and such methods are not practical for either large-scale extensive beef cattle enterprises or free-living mammalian species. Recent developments in UHF (ultra high frequency) proximity logger telemetry devices have been used to provide a continuous pair-wise measure of associations between individual animals for both livestock and wildlife. The objective of this study was to explore the potential of using UHF telemetry to identify the reproductive cycle phenotype in terms of intensity and duration of estrus. The study was conducted using Belmont Red (interbred Africander Brahman Hereford-Shorthorn) cattle grazing irrigated pasture on Belmont Research Station, northeastern Australia. The cow-bull associations from three groups of cows each with one bull were recorded over a 7-week breeding season and the stage of estrus was identified using ultrasonography. Telemetry data from bull and cows, collected over 4 8-day logger deployments, were log transformed and analyzed by ANOVA. Both the number and duration of bull-cow affiliations were significantly (P<0.001) greater in estrous cows compared to anestrus cows. These results support the development of the UHF technology as a hands-off and noninvasive means of gathering socio-sexual information on both wildlife and livestock for reproductive management. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.
Code of Federal Regulations, 2014 CFR
2014-01-01
..., including farmers, ranchers, loggers, agricultural harvesters and fishermen, that engage in the production or harvesting of an agricultural product. Producers may or may not own the land or other production..., value of production, increased diversification of industry, higher labor force participation rates...
Code of Federal Regulations, 2012 CFR
2012-01-01
..., including farmers, ranchers, loggers, agricultural harvesters and fishermen, that engage in the production or harvesting of an agricultural product. Producers may or may not own the land or other production..., value of production, increased diversification of industry, higher labor force participation rates...
Code of Federal Regulations, 2013 CFR
2013-01-01
..., including farmers, ranchers, loggers, agricultural harvesters and fishermen, that engage in the production or harvesting of an agricultural product. Producers may or may not own the land or other production..., value of production, increased diversification of industry, higher labor force participation rates...
NASA Technical Reports Server (NTRS)
1994-01-01
This video presents two examples of NASA Technology Transfer. The first is a Downhole Video Logger, which uses remote sensing technology to help in mining. The second example is the use of satellite image processing technology to enhance ultrasound images taken during pregnancy.
USDA-ARS?s Scientific Manuscript database
This application was designed for farmers, agriculture researchers, and gardeners. The application includes a calculator, a data logger, and a GPS mapping function. It was designed for vegetable farming but can be used for open field applications. The calculator solves for the amount of pesticide,...
Hardwood thinning opportunities in the Lake States.
John A. Sturos
1986-01-01
The symposium presents and discusses new information on the hardwood resource, silviculture, harvesting, economics, and product potential from hardwood thinnings in the Lake States. Included are forest management perspectives from the logger, private industry, and state and federal forest managers.
Prediction of parturition in Holstein dairy cattle using electronic data loggers.
Titler, M; Maquivar, M G; Bas, S; Rajala-Schultz, P J; Gordon, E; McCullough, K; Federico, P; Schuenemann, G M
2015-08-01
The objective of the present study was to assess the effect of parturition on behavioral activity [steps, standing time, lying time, lying bouts (LB), and duration of LB] 4 d before calving using electronic data loggers. Animals (n=132) from 3 herds were housed in similar freestall barns using a prepartum pen 21 d before the expected calving date and were moved into a contiguous individual maternity pen for parturition. Electronic data loggers were placed on a hind leg of prepartum heifers (heifers, n=33) and cows (cows, n=99) at 7±3 d before the expected calving date and removed at 14±3 d in milk. Calving ease (scale 1-4), parity, calving date and time, and stillbirth (born dead or died within 24h) were recorded. The number of steps (no./d), standing time (min/d), lying time (min/d), number of LB (no./d), and duration of LB (min/b) were recorded. Data were analyzed using MIXED procedures of SAS, adjusting for the herd effect. Only cows experiencing unassisted births (calving ease=1) were included in the study. An activity index was developed to predict calving time. Heifers and cows with unassisted births had significantly higher number of steps and longer standing time, decreased lying time, and more LB of shorter duration 24h before calving compared with d -4, -3, and -2. Additionally, the number of LB increased as both heifers and cows approached labor starting on d -2 and peaked at the day of calving. The time since the activity index increased over 50% to parturition did not differ between heifers and cows, and the activity index revealed the shift in activity on average 6h 14min (range from 2h to 14h 15min) before calf birth. This study provided evidence that heifers and cows approaching parturition showed a similar, but distinct, behavioral pattern that can be observed on average 6h before calf birth. The potential benefits of electronic data loggers as predictors of parturition along with proactive management practices should improve the overall survival and welfare of both the dam and calf. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Perumal, G; Ayyagari, A; Chakrabarti, A; Kannan, D; Pati, S; Grewal, H S; Mukherjee, S; Singh, S; Arora, H S
2017-10-25
Substrate-cell interactions for a bioimplant are driven by substrate's surface characteristics. In addition, the performance of an implant and resistance to degradation are primarily governed by its surface properties. A bioimplant typically degrades by wear and corrosion in the physiological environment, resulting in metallosis. Surface engineering strategies for limiting degradation of implants and enhancing their performance may reduce or eliminate the need for implant removal surgeries and the associated cost. In the current study, we tailored the surface properties of stainless steel using submerged friction stir processing (FSP), a severe plastic deformation technique. FSP resulted in significant microstructural refinement from 22 μm grain size for the as-received alloy to 0.8 μm grain size for the processed sample with increase in hardness by nearly 1.5 times. The wear and corrosion behavior of the processed alloy was evaluated in simulated body fluid. The processed sample demonstrated remarkable improvement in both wear and corrosion resistance, which is explained by surface strengthening and formation of a highly stable passive layer. The methylthiazol tetrazolium assay demonstrated that the processed sample is better in supporting cell attachment, proliferation with minimal toxicity, and hemolysis. The athrombogenic characteristic of the as-received and processed samples was evaluated by fibrinogen adsorption and platelet adhesion via the enzyme-linked immunosorbent assay and lactate dehydrogenase assay, respectively. The processed sample showed less platelet and fibrinogen adhesion compared with the as-received alloy, signifying its high thromboresistance. The current study suggests friction stir processing to be a versatile toolbox for enhancing the performance and reliability of currently used bioimplant materials.
Soil moisture monitoring in Candelaro basin, Southern Italy
NASA Astrophysics Data System (ADS)
Campana, C.; Gigante, V.; Iacobellis, V.
2012-04-01
The signature of the hydrologic regime can be investigated, in principle, by recognizing the main mechanisms of runoff generation that take place in the basin and affect the seasonal behavior or the rainfall-driven events. In this framework, besides the implementation of hydrological models, a crucial role should be played by direct observation of key state variables such as soil moisture at different depths and different distances from the river network. In fact, understanding hydrological systems is often limited by the frequency and spatial distribution of observations. Experimental catchments, which are field laboratories with long-term measurements of hydrological variables, are not only sources of data but also sources of knowledge. Wireless distributed sensing platforms are a key technology to address the need for overcoming field limitations such as conflicts between soil use and cable connections. A stand-alone wireless network system has been installed for continuous monitoring of soil water contents at multiple depths along a transect located in Celone basin (sub-basin of Candelaro basin in Puglia, Southern Italy). The transect consists of five verticals, each one having three soil water content sensors at multiple depths: 0,05 m, 0,6 m and 1,2 m below the ground level. The total length of the transect is 307 m and the average distance between the verticals is 77 m. The main elements of the instrumental system installed are: fifteen Decagon 10HS Soil Moisture Sensors, five Decagon Em50R Wireless Radio Data Loggers, one Rain gauge, one Decagon Data Station and one Campbell CR1000 Data Logger. Main advantages of the system as described and presented in this work are that installation of the wireless network system is fast and easy to use, data retrieval and monitoring information over large spatial scales can be obtained in (near) real-time mode and finally other type of sensors can be connected to the system, also offering wide potentials for future applications. First records of the wireless underground network system indicate the presence of interesting patterns in space-time variability of volumetric soil moisture content, that provide evidence of the combined process of vertical infiltration and lateral flow. ACKNOWLEDGEMENT The research in this work is supported by the MIRAGE FP7 project (Grant agreement n. 211732).
Feasibility of Bluetooth Data as a Surrogate Measure of Vehicle Operations
DOT National Transportation Integrated Search
2012-10-01
This research was designed as proof-of-concept study to investigate how Bluetooth data loggers can be used to collect vehicle : operational data over traditional vehicle counting methods. The reliability test included mapping areas for five antenna o...
Folksongs: Magic in Your Classroom.
ERIC Educational Resources Information Center
Seidman, Laurence I.
1985-01-01
Folksongs can be used with all students at all grade levels. Teacher guidelines are provided and three musical themes--whaling in New England, the California Gold Rush, and loggers and lumbering--are used to illustrate how to use folksongs in the classroom. (RM)
Review on stress corrosion and corrosion fatigue failure of centrifugal compressor impeller
NASA Astrophysics Data System (ADS)
Sun, Jiao; Chen, Songying; Qu, Yanpeng; Li, Jianfeng
2015-03-01
Corrosion failure, especially stress corrosion cracking and corrosion fatigue, is the main cause of centrifugal compressor impeller failure. And it is concealed and destructive. This paper summarizes the main theories of stress corrosion cracking and corrosion fatigue and its latest developments, and it also points out that existing stress corrosion cracking theories can be reduced to the anodic dissolution (AD), the hydrogen-induced cracking (HIC), and the combined AD and HIC mechanisms. The corrosion behavior and the mechanism of corrosion fatigue in the crack propagation stage are similar to stress corrosion cracking. The effects of stress ratio, loading frequency, and corrosive medium on the corrosion fatigue crack propagation rate are analyzed and summarized. The corrosion behavior and the mechanism of stress corrosion cracking and corrosion fatigue in corrosive environments, which contain sulfide, chlorides, and carbonate, are analyzed. The working environments of the centrifugal compressor impeller show the behavior and the mechanism of stress corrosion cracking and corrosion fatigue in different corrosive environments. The current research methods for centrifugal compressor impeller corrosion failure are analyzed. Physical analysis, numerical simulation, and the fluid-structure interaction method play an increasingly important role in the research on impeller deformation and stress distribution caused by the joint action of aerodynamic load and centrifugal load.
Gungle, Bruce
2006-01-01
Frequency, timing, and duration of streamflow were monitored in 20 ephemeral-stream channels across the Sierra Vista Subwatershed of the Upper San Pedro Basin, southeastern Arizona, during an 18-month period. One channel (Walnut Gulch) had Agricultural Research Service streamflow-gaging stations in place. The sediments of the remaining 19 ephemeral-stream channels were instrumented with multiple temperature loggers along the channel lengths. A thermograph-interpretation technique was developed in order to determine frequency, timing, and duration of streamflow in these channels. Streamflow onset was characterized by exceedance of a critical minimum drop in temperature within the channel sediments during any 15-minute interval, whereas streamflow cessation was identified by the local temperature minimum that immediately followed the critical temperature drop. All data for the 18-month period from December 1, 2000, to May 31, 2002, were analyzed in terms of monsoon (June 1 to September 19) and nonmonsoon (September 20 to May 31) periods. Nonmonsoon precipitation during the 2000-2002 study period (excludes October and November 2000) was 82 percent and 39 percent of the 30-year average, respectively, whereas monsoon precipitation during 2001 was 99 percent of the 30-year average. Ephemeral streamflow was detected at least once during the monitoring period at 87 percent of the monitoring sites (45 of the 52 sites that returned useful data; includes 4 streamflow-gaging stations). The summer monsoon period accounted for 82 percent of all streamflow events by number and 71 percent of all events by total streamflow duration. Nonmonsoon streamflow events peaked in number, total streamflow duration, and mean streamflow duration midway between the Huachuca Mountains and the San Pedro River on the west side of the subwatershed. These three streamflow parameters dropped off sharply about 10 kilometers from the mountain front. The number and total duration of nonmonsoon streamflows on the east side of the subwatershed trended downward with increased distance from the mountain fronts. Monsoon streamflow events were more evenly distributed across the subwatershed than nonmonsoon events, and the number and duration of streamflows generally trended upward with distance from the mountain fronts. Additional years of data are needed to determine whether these patterns are consistent year to year, or were due to randomness in the spatial distribution of precipitation. Streamflows in three ephemeral-stream channels were analyzed in detail. More than two-thirds of the streamflow events detected in each of these channels occurred at no more than one monitoring site along the channel length. In only one of the three channels-Garden Canyon-was a streamflow event detected at all logger sites along its length. Five temperature loggers provided data from urbanized areas, and these loggers detected streamflow more than 50 percent more often and of a duration nearly three times greater than did temperature loggers across the rural parts of the subwatershed. Because historical records do not indicate that more precipitation occurs in the urbanized area than in the rural areas, the increased frequency of flow detection in the urban area is attributed to an increase in runoff from the impervious surfaces throughout the urbanized area.
"Artificial intelligence" at streamgaging stations
R. B. Thomas
1985-01-01
Two types of problems are related to collecting hydrologic data at stream gaging stations. One includes the technical/logistical questions associated with measuring and transferring data for processing. Effort spent on these problems ranges from improving devices for sensing data to using electronic data loggers.
The Corrosion and Preservation of Iron Antiques.
ERIC Educational Resources Information Center
Walker, Robert
1982-01-01
Discusses general corrosion reactions (iron to rust), including corrosion of iron, sulfur dioxide, chlorides, immersed corrosion, and underground corrosion. Also discusses corrosion inhibition, including corrosion inhibitors (anodic, cathodic, mixed, organic); safe/dangerous inhibitors; and corrosion/inhibition in concrete/marble, showcases/boxes,…
Broell, Franziska; Burnell, Celene; Taggart, Christopher T
2016-03-01
Animal-borne data loggers allow movement, associated behaviours and energy expenditure in fish to be quantified without direct observations. As with any tagging, tags that are attached externally may adversely affect fish behaviour, swimming efficiency and survival. We report on free-swimming wild Atlantic cod (Gadus morhua) held in a large mesocosm that exhibited distinctly aberrant rotational swimming (scouring) when externally tagged with accelerometer data loggers. To quantify the phenomenon, the cod were tagged with two sizes of loggers (18 and 6 g; <2% body mass) that measured tri-axial acceleration at 50 Hz. An automated algorithm, based on body angular rotation, was designed to extract the scouring movements from the acceleration signal (98% accuracy). The algorithm also identified the frequency pattern and associated energy expenditure of scouring in relation to tag load (% body weight). The average per cent time spent scouring (5%) was independent of tag load. The vector of the dynamic body acceleration (VeDBA), used as a proxy for energy expenditure, increased with tag load (r(2)=0.51), and suggests that fish with large tags spent more energy when scouring than fish with small tags. The information allowed us to determine potential detrimental effects of an external tag on fish behaviour and how these effects may be mitigated by tag size. The algorithm can potentially identify similar rotational movements associated with spawning, courtship, feeding and parasite-load shedding in the wild. The results infer a more careful interpretation of data derived from external tags and the careful consideration of tag type, drag, buoyancy and placement, as well as animal buoyancy and species. © 2016. Published by The Company of Biologists Ltd.
Creative Uses of Custom Electronics for Environmental Monitoring
NASA Astrophysics Data System (ADS)
Hicks, S.; Aufdenkampe, A. K.; Montgomery, D. S.
2012-12-01
The ability to build custom electronic devices specifically suited to a unique task has gotten easier and cheaper, thanks to the recent popularity of open source electronics platforms like Arduino. Using Arduino-based processor boards, we have been creating a variety of helpful devices to perform functions that would have been too expensive to implement with standard methods and commercial hardware. The Christina River Basin CZO is currently operating dozens of homemade dataloggers that are connected to different types of environmental sensors. Most of these Arduino loggers have been deployed for over a year, so our experiences with them and their sensors have taught us a lot about the reliability and accuracy of both the loggers and the sensors. Some loggers also have the capability for wireless radio or ethernet data transmission for reporting live data to web sites for instant graphing or archiving. Other Arduino devices have the ability to be controlled remotely through web sites or telephones, making it easy to remotely trigger sample pumps or valves. The open-source nature of Arduino means collaboration is easy because the circuit schematics and source code for programming the boards can be shared between users. And because Arduino devices are easy to use and program, we developed an interface board that allows educators to easily connect a variety of inexpensive environmental sensors to an Arduino board. Then the students can write and upload simple programs to interact with the sensors, making it a very effective tool for teaching electronics and environmental science at the same time. The flexibility and capability of electronics prototyping platforms like Arduino mean these simple boards can cheaply and effectively perform a countless number of tasks for projects in environmental science and education.
Levin, Iris I.; Zonana, David M.; Burt, John M.; Safran, Rebecca J.
2015-01-01
Proximity logging is a new tool for understanding social behavior as it allows for accurate quantification of social networks. We report results from field calibration and deployment tests of miniaturized proximity tags (Encounternet), digital transceivers that log encounters between tagged individuals. We examined radio signal behavior in relation to tag attachment (tag, tag on bird, tag on saline-filled balloon) to understand how radio signal strength is affected by the tag mounting technique used for calibration tests. We investigated inter-tag and inter-receiver station variability, and in each calibration test we accounted for the effects of antennae orientation. Additionally, we used data from a live deployment on breeding barn swallows (Hirundo rustica erythrogaster) to analyze the quality of the logs, including reciprocal agreement in dyadic logs. We evaluated the impact (in terms of mass changes) of tag attachment on the birds. We were able to statistically distinguish between RSSI values associated with different close-proximity (<5m) tag-tag distances regardless of antennae orientation. Inter-tag variability was low, but we did find significant inter-receiver station variability. Reciprocal agreement of dyadic logs was high and social networks were constructed from proximity tag logs based on two different RSSI thresholds. There was no evidence of significant mass loss in the time birds were wearing tags. We conclude that proximity loggers are accurate and effective for quantifying social behavior. However, because RSSI and distance cannot be perfectly resolved, data from proximity loggers are most appropriate for comparing networks based on specific RSSI thresholds. The Encounternet system is flexible and customizable, and tags are now light enough for use on small animals (<50g). PMID:26348329
Research on a new type of fiber Bragg grating based corrosion sensor
NASA Astrophysics Data System (ADS)
Li, Peng; Song, Shide; Wang, Xiaona; Zhou, Weijie; Zhang, Zuocai
2015-08-01
Investigations of the corrosion of rebars in concrete structures are widely studied because of the serious damage to concrete caused by rebar corrosion. The rebar corrosion products in reinforced concrete take up 2~6 times the volume of the rebar. Based on this principle, a new type of fiber Bragg grating (FBG) corrosion sensor is proposed in this paper, which consists of two sensors, an FBG corrosion measurement sensor to measure the expansion strain caused by rebar corrosion, and a temperature compensation sensor to eliminate the cross-sensitivity of FBG corrosion sensor. The corrosion rate is derived by the wavelength shift of FBG corrosion sensor, so rebar corrosion can be monitored and assessed by the FBG wavelength shift. A customized rebar with epoxy fixing groove is designed to install a corrosion sensor on its surface and an embedded temperature compensation sensor. The corrosion sensor is embedded in cement mortar and subsequently casted in concrete. The performance of the corrosion sensor is studied in an accelerated electrochemical corrosion test. Experimental results show that the new type of corrosion sensor has advantage of relatively large measurement range of corrosion rate. The corrosion sensor is suitable to monitor slightly and moderately corroded rebars.
Synergy effect of naphthenic acid corrosion and sulfur corrosion in crude oil distillation unit
NASA Astrophysics Data System (ADS)
Huang, B. S.; Yin, W. F.; Sang, D. H.; Jiang, Z. Y.
2012-10-01
The synergy effect of naphthenic acid corrosion and sulfur corrosion at high temperature in crude oil distillation unit was studied using Q235 carbon-manganese steel and 316 stainless steel. The corrosion of Q235 and 316 in corrosion media containing sulfur and/or naphthenic acid at 280 °C was investigated by weight loss, scanning electron microscope (SEM), EDS and X-ray diffractometer (XRD) analysis. The results showed that in corrosion media containing only sulfur, the corrosion rate of Q235 and 316 first increased and then decreased with the increase of sulfur content. In corrosion media containing naphthenic acid and sulfur, with the variations of acid value or sulfur content, the synergy effect of naphthenic acid corrosion and sulfur corrosion has a great influence on the corrosion rate of Q235 and 316. It was indicated that the sulfur accelerated naphthenic acid corrosion below a certain sulfur content but prevented naphthenic acid corrosion above that. The corrosion products on two steels after exposure to corrosion media were investigated. The stable Cr5S8 phases detected in the corrosion products film of 316 were considered as the reason why 316 has greater corrosion resistance to that of Q235.
Tax tips for forest landowners for the 2008 tax year
Linda Wang; John L. Greene
2009-01-01
This article summarizes key federal income tax provisions for forestland owners, foresters, loggers, forest product businesses, and tax practioners, and is current as of October 1, 2008. Consult your tax and legal professionals for advice on your particular tax situation.
Physical characterization of intertidal estuarine plant habitats over time may reveal distribution-limiting thresholds. Temperature data from loggers embedded in sediment in transects crossing Zostera marina and Z. japonica habitats in lower Yaquina Bay, Oregon display signific...
ERIC Educational Resources Information Center
Daniels, Elva S.
1983-01-01
A teaching unit uses the songs of sailors, loggers, coal miners, and other workers to illustrate how the United States was built in the nineteenth century. Words and music for seven songs are given, along with classroom activities to help children understand occupations and industries during that time. (PP)
Monitoring tools of COMPASS experiment at CERN
NASA Astrophysics Data System (ADS)
Bodlak, M.; Frolov, V.; Huber, S.; Jary, V.; Konorov, I.; Levit, D.; Novy, J.; Salac, R.; Tomsa, J.; Virius, M.
2015-12-01
This paper briefly introduces the data acquisition system of the COMPASS experiment and is mainly focused on the part that is responsible for the monitoring of the nodes in the whole newly developed data acquisition system of this experiment. The COMPASS is a high energy particle experiment with a fixed target located at the SPS of the CERN laboratory in Geneva, Switzerland. The hardware of the data acquisition system has been upgraded to use FPGA cards that are responsible for data multiplexing and event building. The software counterpart of the system includes several processes deployed in heterogenous network environment. There are two processes, namely Message Logger and Message Browser, taking care of monitoring. These tools handle messages generated by nodes in the system. While Message Logger collects and saves messages to the database, the Message Browser serves as a graphical interface over the database containing these messages. For better performance, certain database optimizations have been used. Lastly, results of performance tests are presented.
The NASA rocky mountain space grant high altitude research balloon project
NASA Astrophysics Data System (ADS)
Moore, R. G.; Espy, P.
1994-02-01
A group of U.S. universities, under the auspices of NASA's Space Grant College and Fellowship Program, has initiated a super-pressure balloon research project to measure ozone column density in the atmosphere above 20 kilometers, together with stratospheric circulation between 20 km and 40 km, over the continental U.S.A. Data from a balloon-borne ultraviolet spectrometer, together with time, altitude, latitude and longitude information from a Global Positioning System receiver, are recorded at ten-minute intervals during daytime hours in an on-board solid-state data logger. Coded messages are transmitted nightly from selected amateur radio ground stations to a receiver in the balloon gondola to command the transmission of packet radio bursts from the data logger to the ground stations, for relay to a central data collection and analysis facility at Utah State University. Discussions are under way with radio amateurs and members of the international scientific balloon community regarding extension of flights to cover the earth's northern hemisphere.
The NASA rocky moutain space grant high altitude research balloon project
NASA Astrophysics Data System (ADS)
Moore, R. G.; Espy, P.
1994-02-01
A group of U.S. universities, under the auspices of NASA's Space Grant College and Fellowship Program, has initiated a super-pressure balloon research project to measure ozone column density in the atmosphere above 20 kilometers, together with stratospheric circulation between 20 km and 40 km, over the continental U.S.A. Data from a balloon-borne ultraviolet spectrometer, together with time, altitude, latitude and longitude information from a Global Positioning System reciever, are recorded at ten-minute intervals during daytime hours in an on-board solid-state data logger. Coded messages are transmitted nightly from selected amateur radio ground stations to a receiver in the balloon gondola to command transmission of packet radio bursts from the data logger to the ground stations, for relay to a central data collection and analysis facility at Utah State University. Discussions are under way with radio amateurs and members of the international scientific balloon community regarding extension of flights to cover the earth's northern hemisphere.
2012-01-01
Background Ariadne’s house, located at the city center of ancient Pompeii, is of great archaeological value due to the fresco paintings decorating several rooms. In order to assess the risks for long-term conservation affecting the valuable mural paintings, 26 temperature data-loggers and 26 relative humidity data-loggers were located in four rooms of the house for the monitoring of ambient conditions. Results Data recorded during 372 days were analyzed by means of graphical descriptive methods and analysis of variance (ANOVA). Results revealed an effect of the roof type and number of walls of the room. Excessive temperatures were observed during the summer in rooms covered with transparent roofs, and corrective actions were taken. Moreover, higher humidity values were recorded by sensors on the floor level. Conclusions The present work provides guidelines about the type, number, calibration and position of thermohygrometric sensors recommended for the microclimate monitoring of mural paintings in outdoor or semi-confined environments. PMID:23190798
Helmuth, Brian; Choi, Francis; Matzelle, Allison; Torossian, Jessica L.; Morello, Scott L.; Mislan, K.A.S.; Yamane, Lauren; Strickland, Denise; Szathmary, P. Lauren; Gilman, Sarah E.; Tockstein, Alyson; Hilbish, Thomas J.; Burrows, Michael T.; Power, Anne Marie; Gosling, Elizabeth; Mieszkowska, Nova; Harley, Christopher D.G.; Nishizaki, Michael; Carrington, Emily; Menge, Bruce; Petes, Laura; Foley, Melissa M.; Johnson, Angela; Poole, Megan; Noble, Mae M.; Richmond, Erin L.; Robart, Matt; Robinson, Jonathan; Sapp, Jerod; Sones, Jackie; Broitman, Bernardo R.; Denny, Mark W.; Mach, Katharine J.; Miller, Luke P.; O’Donnell, Michael; Ross, Philip; Hofmann, Gretchen E.; Zippay, Mackenzie; Blanchette, Carol; Macfarlan, J.A.; Carpizo-Ituarte, Eugenio; Ruttenberg, Benjamin; Peña Mejía, Carlos E.; McQuaid, Christopher D.; Lathlean, Justin; Monaco, Cristián J.; Nicastro, Katy R.; Zardi, Gerardo
2016-01-01
At a proximal level, the physiological impacts of global climate change on ectothermic organisms are manifest as changes in body temperatures. Especially for plants and animals exposed to direct solar radiation, body temperatures can be substantially different from air temperatures. We deployed biomimetic sensors that approximate the thermal characteristics of intertidal mussels at 71 sites worldwide, from 1998-present. Loggers recorded temperatures at 10–30 min intervals nearly continuously at multiple intertidal elevations. Comparisons against direct measurements of mussel tissue temperature indicated errors of ~2.0–2.5 °C, during daily fluctuations that often exceeded 15°–20 °C. Geographic patterns in thermal stress based on biomimetic logger measurements were generally far more complex than anticipated based only on ‘habitat-level’ measurements of air or sea surface temperature. This unique data set provides an opportunity to link physiological measurements with spatially- and temporally-explicit field observations of body temperature. PMID:27727238
NASA Astrophysics Data System (ADS)
Helmuth, Brian; Choi, Francis; Matzelle, Allison; Torossian, Jessica L.; Morello, Scott L.; Mislan, K. A. S.; Yamane, Lauren; Strickland, Denise; Szathmary, P. Lauren; Gilman, Sarah E.; Tockstein, Alyson; Hilbish, Thomas J.; Burrows, Michael T.; Power, Anne Marie; Gosling, Elizabeth; Mieszkowska, Nova; Harley, Christopher D. G.; Nishizaki, Michael; Carrington, Emily; Menge, Bruce; Petes, Laura; Foley, Melissa M.; Johnson, Angela; Poole, Megan; Noble, Mae M.; Richmond, Erin L.; Robart, Matt; Robinson, Jonathan; Sapp, Jerod; Sones, Jackie; Broitman, Bernardo R.; Denny, Mark W.; Mach, Katharine J.; Miller, Luke P.; O'Donnell, Michael; Ross, Philip; Hofmann, Gretchen E.; Zippay, Mackenzie; Blanchette, Carol; Macfarlan, J. A.; Carpizo-Ituarte, Eugenio; Ruttenberg, Benjamin; Peña Mejía, Carlos E.; McQuaid, Christopher D.; Lathlean, Justin; Monaco, Cristián J.; Nicastro, Katy R.; Zardi, Gerardo
2016-10-01
At a proximal level, the physiological impacts of global climate change on ectothermic organisms are manifest as changes in body temperatures. Especially for plants and animals exposed to direct solar radiation, body temperatures can be substantially different from air temperatures. We deployed biomimetic sensors that approximate the thermal characteristics of intertidal mussels at 71 sites worldwide, from 1998-present. Loggers recorded temperatures at 10-30 min intervals nearly continuously at multiple intertidal elevations. Comparisons against direct measurements of mussel tissue temperature indicated errors of ~2.0-2.5 °C, during daily fluctuations that often exceeded 15°-20 °C. Geographic patterns in thermal stress based on biomimetic logger measurements were generally far more complex than anticipated based only on ‘habitat-level’ measurements of air or sea surface temperature. This unique data set provides an opportunity to link physiological measurements with spatially- and temporally-explicit field observations of body temperature.
Development of oxygen meters for the use in lead-bismuth
NASA Astrophysics Data System (ADS)
Konys, J.; Muscher, H.; Voß, Z.; Wedemeyer, O.
2001-07-01
Liquid lead and the eutectic lead-bismuth alloy (PbBi) are considered both as a spallation target and coolant of an accelerator driven system (ADS) for the transmutation of long-lived actinides from nuclear waste into shorter living isotopes. It is known that both, pure lead and PbBi, exhibit a high corrosivity against austenitic and ferritic steels, because of the high solubility of nickel and iron in PbBi. One way of reducing the strong corrosion is the in situ formation of stable oxide scales on the steel surfaces. Thermodynamic calculations and experimental results have confirmed, that the control of oxygen in lead or PbBi within a defined activity range can lead to acceptable corrosion rates. To control the level of oxygen dissolved in lead or PbBi, a sensor for measuring the oxygen activity is required. Within the sodium fast breeder reactor development, an adequate technique was established for estimating oxygen in liquid sodium. This knowledge can be used for other metal/oxygen systems like oxygen in PbBi. For measuring the oxygen activity and calculating its concentration, the relevant thermodynamic and solubility data have to be considered. Two reference electrode systems: Pt/air and In/In 2O 3 (both based on yttria-stabilized zirconia as solid electrolyte) are investigated to evaluate their electromotive force (EMF)-temperature dependency in saturated and unsaturated oxygen solutions. Results with both types of oxygen meters in PbBi at different oxygen levels were compared with theoretical calculations. The experimental data indicate that the design, construction and integration of an oxygen control unit in a large scale PbBi-loop seems to be very feasible.
Microencapsulation Technology for Corrosion Mitigation by Smart Coatings
NASA Technical Reports Server (NTRS)
Buhrow, Jerry; Li, Wenyan; Jolley, Scott; Calle, Luz M.
2011-01-01
A multifunctional, smart coating for the autonomous control of corrosion is being developed based on micro-encapsulation technology. Corrosion indicators as well as corrosion inhibitors have been incorporated into microcapsules, blended into several paint systems, and tested for corrosion detection and protection effectiveness. This paper summarizes the development, optimization, and testing of microcapsules specifically designed to be incorporated into a smart coating that will deliver corrosion inhibitors to mitigate corrosion autonomously. Key words: smart coating, corrosion inhibition, microencapsulation, microcapsule, pH sensitive microcapsule, corrosion inhibitor, corrosion protection pain
Study on Corrosion-induced Crack Initiation and Propagation of Sustaining Loaded RCbeams
NASA Astrophysics Data System (ADS)
Zhong, X. P.; Li, Y.; Yuan, C. B.; Yang, Z.; Chen, Y.
2018-05-01
For 13 pieces of reinforced concrete beams with HRB500 steel bars under long-term sustained loads, at time of corrosion-induced initial crack of concrete, and corrosion-induced crack widths of 0.3mm and 1mm, corrosion of steel bars and time-varying behavior of corrosion-induced crack width were studied by the ECWD (Electro-osmosis - constant Current – Wet and Dry cycles) accelerated corrosion method. The results show that when cover thickness was between 30 and 50mm,corrosion rates of steel bars were between 0.8% and 1.7% at time of corrosion-induced crack, and decreased with increasing concrete cover thickness; when corrosion-induced crack width was 0.3mm, the corrosion rate decreased with increasing steel bar diameter, and increased with increasing cover thickness; its corrosion rate varied between 0.98% and 4.54%; when corrosion-induced crack width reached 1mm, corrosion rate of steel bars was between 4% and 4.5%; when corrosion rate of steel bars was within 5%, the maximum and average corrosion-induced crack and corrosion rate of steel bars had a good linear relationship. The calculation model predicting the maximum and average width of corrosion-induced crack is given in this paper.
Sun, Bo; Ye, Tianyuan; Feng, Qiang; Yao, Jinghua; Wei, Mumeng
2015-01-01
This paper studies the corrosion behavior of B10 copper-nickel alloy in marine environment. Accelerated degradation test under marine environmental conditions was designed and performed based on the accelerated testing principle and the corrosion degradation mechanism. With the prolongation of marine corrosion time, the thickness of Cu2O film increased gradually. Its corrosion product was Cu2(OH)3Cl, which increased in quantity over time. Cl− was the major factor responsible for the marine corrosion of copper and copper alloy. Through the nonlinear fitting of corrosion rate and corrosion quantity (corrosion weight loss), degradation data of different corrosion cycles, the quantitative effects of two major factors, i.e., dissolved oxygen (DO) and corrosion medium temperature, on corrosion behavior of copper alloy were analyzed. The corrosion failure prediction models under different ambient conditions were built. One-day corrosion weight loss under oxygenated stirring conditions was equivalent to 1.31-day weight loss under stationary conditions, and the corrosion rate under oxygenated conditions was 1.31 times higher than that under stationary conditions. In addition, corrosion medium temperature had a significant effect on the corrosion of B10 copper sheet. PMID:28793549
Sun, Bo; Ye, Tianyuan; Feng, Qiang; Yao, Jinghua; Wei, Mumeng
2015-09-10
This paper studies the corrosion behavior of B10 copper-nickel alloy in marine environment. Accelerated degradation test under marine environmental conditions was designed and performed based on the accelerated testing principle and the corrosion degradation mechanism. With the prolongation of marine corrosion time, the thickness of Cu₂O film increased gradually. Its corrosion product was Cu₂(OH)₃Cl, which increased in quantity over time. Cl - was the major factor responsible for the marine corrosion of copper and copper alloy. Through the nonlinear fitting of corrosion rate and corrosion quantity (corrosion weight loss), degradation data of different corrosion cycles, the quantitative effects of two major factors, i.e. , dissolved oxygen (DO) and corrosion medium temperature, on corrosion behavior of copper alloy were analyzed. The corrosion failure prediction models under different ambient conditions were built. One-day corrosion weight loss under oxygenated stirring conditions was equivalent to 1.31-day weight loss under stationary conditions, and the corrosion rate under oxygenated conditions was 1.31 times higher than that under stationary conditions. In addition, corrosion medium temperature had a significant effect on the corrosion of B10 copper sheet.
DOT National Transportation Integrated Search
2017-01-01
New traffic signal controllers, which have advanced data collection abilities, offer better information about the response of traffic signal timings to traffic flows. However, traffic engineers need more than raw data. The controllers must be set up ...
29 CFR 780.203 - Performance of operations on a farm but not by the farmer.
Code of Federal Regulations, 2010 CFR
2010-07-01
... on a farm undertaken on behalf of the farmer or on behalf of the buyer of the logs or the resulting lumber by a contract logger or sawmill owner are not within the scope of agriculture unless it can be...
DOT National Transportation Integrated Search
2017-01-01
The arterial traffic signal performance measures were not used to their fullest potential in the past. The development of traffic signal controllers with event-based, high-resolution data logging capabilities enabled the advances in derivation and vi...
Improving Attachments of Non-Invasive (Type III) Electronic Data Loggers to Cetaceans
2011-09-30
Micro texturing of the suction cup to reduced leakage: Objective: Use microtexturing to create a superhydrophobic barrier between the lip and the...surface area of a solid, thereby amplifying the natural hydrophobicity of a surface. Superhydrophobicity is created by interfacial tension forces that
ERIC Educational Resources Information Center
Killam, Alice Dow
1994-01-01
A former teacher reminisces about her teaching experiences during the 1920s in a rural school along the Aroostook River in Wade, Maine. Each year, when the boat carrying the cook for loggers upriver arrived, she and her students went aboard and received a special treat of warm molasses cake. (LP)
ERIC Educational Resources Information Center
Miles, Donna
2001-01-01
In response to high numbers of preventable fatal accidents in the logging industry, the Occupational Safety and Health Administration (OSHA) developed a week-long logger safety training program that includes hands-on learning of safety techniques in the woods. Reaching small operators has been challenging; outreach initiatives in Maine, North…
USDA-ARS?s Scientific Manuscript database
Micrometeorological methods and ecosystem-scale energy and mass flux density measurements have become increasingly important in soil, agricultural, and environmental sciences. For many scientists without formal training in atmospheric science, these techniques are relatively inaccessible. Eddy cov...
INFLUENCE OF RESIDENTIAL HVAC DUTY CYCLE ON INDOOR AIR QUALITY
Measurements of duty cycle, the fraction of time the heating and cooling (HVAC) system was operating, were made in homes during the spring season of the RTP Particulate Matter Panel Study and the Tampa Asthmatic Children's Study. A temperature sensor/logger placed on an outlet...
Wireless sensor network for irrigation application in cotton
USDA-ARS?s Scientific Manuscript database
A wireless sensor network was deployed in a cotton field to monitor soil water status for irrigation. The network included two systems, a Decagon system and a microcontroller-based system. The Decagon system consists of soil volumetric water-content sensors, wireless data loggers, and a central data...
A Multifunctional Coating for Autonomous Corrosion Control
NASA Technical Reports Server (NTRS)
Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott t.
2011-01-01
Nearly all metals and their alloys are subject to corrosion that causes them to lose their structural integrity or other critical functionality. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to indicate it and control it. The multi-functionality of the coating is based on microencapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of existing microcapsulation designs, the corrosion controlled release function that triggers the delivery of corrosion indicators and inhibitors on demand, only when and where needed. Microencapsulation of self-healing agents for autonomous repair of mechanical damage to the coating is also being pursued. Corrosion indicators, corrosion inhibitors, as well as self-healing agents, have been encapsulated and dispersed into several paint systems to test the corrosion detection, inhibition, and self-healing properties of the coating. Key words: Corrosion, coating, autonomous corrosion control, corrosion indication, corrosion inhibition, self-healing coating, smart coating, multifunctional coating, microencapsulation.
Corrosion Performance of High Damping Alloys in 3.5% Sodium Chloride Environment.
1987-09-01
Electrochemical Technique, Sea Exposure, Scanning Electron Microscopy. 9 .,5MAZT (Continue on rvre of necessary ad 4*er.#y by boock numbver# -The... electrochemical nature of corrosion provides a means of determining an almost instantaneous corrosion rate. Corrosion rate and the nature of corrosion attack were... electrochemical nature of corrosion provides a means of determining an almost instantaneous corrosion rate. Corrosion rate and the nature of
A Multifunctional Smart Coating for Autonomous Corrosion Control
NASA Technical Reports Server (NTRS)
Calle, Luz Marina; Buhrow, Jerry W.; Jolley, Scott T.
2012-01-01
Corrosion is a destructive process that often causes failure in metallic components and structures. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to control it. The multi-functionality of the coating is based on micro-encapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of other existing microcapsules designs, the corrosion controlled release function that allows the delivery of corrosion indicators and inhibitors on demand only when and where needed. Corrosion indicators as well as corrosion inhibitors have been incorporated into microcapsules, blended into several paint systems, and tested for corrosion detection and protection efficacy. This
A Multifunctional Coating for Autonomous Corrosion Control
NASA Technical Reports Server (NTRS)
Calle, Luz M.; Hintze, Paul E.; Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott T.
2010-01-01
Corrosion is a destructive process that often causes failure in metallic components and structures. Protective coatings are the most commonly used method of corrosion control. However, progressively stricter environmental regulations have resulted in the ban of many commercially available corrosion protective coatings due to the harmful effects of their solvents or corrosion inhibitors. This work concerns the development of a multifunctional, smart coating for the autonomous control of corrosion. This coating is being developed to have the inherent ability to detect the chemical changes associated with the onset of corrosion and respond autonomously to control it. The multi-functionality of the coating is based on microencapsulation technology specifically designed for corrosion control applications. This design has, in addition to all the advantages of other existing microcapsules designs, the corrosion controlled release function that allows the delivery of corrosion indicators and inhibitors on demand only when and where they are needed. Corrosion indicators as well as corrosion inhibitors have been incorporated into the microcapsules, blended into several paint systems, and tested for corrosion detection and protection efficacy.
To better characterize the relationships between both adjacent hydrology/ precipitation and nutrient processing with groundwater level fluctuations, continuous water level data are being collected across three dominant wetland types, each with varied landscape characteristics. Th...
40 CFR 89.310 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2010 CFR
2010-07-01
... to § 89.323. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates... generally not be used. (2) Some high resolution read-out systems, such as computers, data loggers, and so..., using good engineering judgement, below 15 percent of full scale are made to ensure the accuracy of the...
40 CFR 86.1338-84 - Emission measurement accuracy.
Code of Federal Regulations, 2010 CFR
2010-07-01
... engineering practice dictates that exhaust emission sample analyzer readings below 15 percent of full scale... computers, data loggers, etc., can provide sufficient accuracy and resolution below 15 percent of full scale... spaced points, using good engineering judgement, below 15 percent of full scale are made to ensure the...
Modeling and Simulation Network Data Standards
2011-09-30
COMBATXXI Movement Logger Data Output Dictionary. Field # Geocentric Coordinates (GCC) Heading Geodetic Coordinates (GDC) Heading Universal...B-8 Field # Geocentric Coordinates (GCC) Heading Geodetic Coordinates (GDC) Heading Universal Transverse Mercator (UTM) Heading...FKSM Fort Knox Supplemental Material FM field manual GCC geocentric coordinates GDC geodetic coordinates GIG global information grid
Signal processing techniques were applied to high-resolution time series data obtained from conductivity loggers placed upstream and downstream of a wastewater treatment facility along a river. Data was collected over 14-60 days, and several seasons. The power spectral densit...
Pressure-Height Properties of Water with Automated Data Collection
ERIC Educational Resources Information Center
Bates, Alan
2013-01-01
Instrumentation available for teachers and students has changed considerably during the last 20 years. The data logger-sensor system has the advantage of taking reliable measurements over time with suitable sample rates. This experiment is not an open-ended investigation but an opportunity to explore the established relationship between the…
Forestry BMP Implementation Costs for Virginia
R.M. Shaffer; H.L. Haney; E.G. Worrell; W.M. Aust
1998-01-01
Forestry Best Management Practices (BMPs) are operational techniques used to protect water quality during timber harvesting operations. The implementation cost of BMPs is important to loggers, forest landowners, and the forest industry. This study provides an estimate of BMP implementation cost on a per harvested acre basis for the coastal plain, Piedmont, and...
RELATIONSHIPS BETWEEN HABITAT ARRANGEMENT AND JUVENILE WINTER FLOUNDER DENSITY IN NARRAGANSETT BAY
We used aerial photography in conjunction with a 1-m beam trawl attached to a videocamera with GPS overwrite and a YSI water quality logger to quantify fish densities and characterize habitats in Narragansett Bay and in Rhode Island's coastal lagoons. We compared fish counts fro...
40 CFR 90.314 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2014 CFR
2014-07-01
... engineering practice. Adhere to the minimum requirements given in §§ 90.316 through 90.325 and § 90.409. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates that exhaust emission...) Some high resolution read-out systems, such as computers, data loggers, and so forth, can provide...
40 CFR 90.314 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2011 CFR
2011-07-01
... engineering practice. Adhere to the minimum requirements given in §§ 90.316 through 90.325 and § 90.409. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates that exhaust emission...) Some high resolution read-out systems, such as computers, data loggers, and so forth, can provide...
40 CFR 90.314 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2012 CFR
2012-07-01
... engineering practice. Adhere to the minimum requirements given in §§ 90.316 through 90.325 and § 90.409. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates that exhaust emission...) Some high resolution read-out systems, such as computers, data loggers, and so forth, can provide...
40 CFR 86.1338-84 - Emission measurement accuracy.
Code of Federal Regulations, 2013 CFR
2013-07-01
... engineering practice dictates that exhaust emission sample analyzer readings below 15 percent of full scale... computers, data loggers, etc., can provide sufficient accuracy and resolution below 15 percent of full scale... spaced points, using good engineering judgement, below 15 percent of full scale are made to ensure the...
40 CFR 89.310 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2011 CFR
2011-07-01
... to § 89.323. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates... generally not be used. (2) Some high resolution read-out systems, such as computers, data loggers, and so..., using good engineering judgement, below 15 percent of full scale are made to ensure the accuracy of the...
40 CFR 89.310 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2013 CFR
2013-07-01
... to § 89.323. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates... generally not be used. (2) Some high resolution read-out systems, such as computers, data loggers, and so..., using good engineering judgement, below 15 percent of full scale are made to ensure the accuracy of the...
40 CFR 86.1338-84 - Emission measurement accuracy.
Code of Federal Regulations, 2012 CFR
2012-07-01
... engineering practice dictates that exhaust emission sample analyzer readings below 15 percent of full scale... computers, data loggers, etc., can provide sufficient accuracy and resolution below 15 percent of full scale... spaced points, using good engineering judgement, below 15 percent of full scale are made to ensure the...
40 CFR 86.1338-84 - Emission measurement accuracy.
Code of Federal Regulations, 2011 CFR
2011-07-01
... engineering practice dictates that exhaust emission sample analyzer readings below 15 percent of full scale... computers, data loggers, etc., can provide sufficient accuracy and resolution below 15 percent of full scale... spaced points, using good engineering judgement, below 15 percent of full scale are made to ensure the...
40 CFR 90.314 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2013 CFR
2013-07-01
... engineering practice. Adhere to the minimum requirements given in §§ 90.316 through 90.325 and § 90.409. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates that exhaust emission...) Some high resolution read-out systems, such as computers, data loggers, and so forth, can provide...
40 CFR 89.310 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2012 CFR
2012-07-01
... to § 89.323. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates... generally not be used. (2) Some high resolution read-out systems, such as computers, data loggers, and so..., using good engineering judgement, below 15 percent of full scale are made to ensure the accuracy of the...
40 CFR 89.310 - Analyzer accuracy and specifications.
Code of Federal Regulations, 2014 CFR
2014-07-01
... to § 89.323. (c) Emission measurement accuracy—Bag sampling. (1) Good engineering practice dictates... generally not be used. (2) Some high resolution read-out systems, such as computers, data loggers, and so..., using good engineering judgement, below 15 percent of full scale are made to ensure the accuracy of the...
Measurements of duty cycle , the fraction of time the heating and cooling (HVAC) system was operating, were made in each participant's home during the spring season of the RTP Particulate Matter Panel Study. A miniature temperature sensor/data logger combination placed on the ...
Improving Attachments of Non-Invasive (Type III) Electronic Data Loggers to Cetaceans
2014-09-30
the assessment tag impact on animal health and well-being. Specifically, we are working to develop methods that will enable the accurate estimates...currently not available for any marine mammal, about animal health and activity has the potential to revolutionize how animals are cared for in these
Maya Traditional Knowledge: Preserving Forests in Guatemala.
ERIC Educational Resources Information Center
Bernstein, Jacob
1996-01-01
In the mountains of western Guatemala, Maya K'iche communities draw on extensive indigenous knowledge of the local ecosystem to manage sections of forest allocated as community responsibility for generations. Supported by spiritual beliefs, community elders seek to guide the use and preservation of the forest despite illegal loggers, corrupt…
Cost of wetland protection using a Christy cable yarder
Chris B. LeDoux; John E. Baumgras; Edwin S. Miyata
1990-01-01
Forest managers, loggers, land-use planners, and other decision makers need an understanding of estimating the cost of protecting wetlands using cable logging systems to harvest timber products. Results suggest that protection costs can range from $245 to $490 per acre depending on the degree of protection desired.
Dennis P. Bradley; Frank E. Biltonen
1973-01-01
Describes the productivity of selected aspen pulpwood loggers in northern Minnesota. The most important factors affecting productivity were the ratio of harvested trees per acre to total trees per acre, harvested volume per acre, and the spacing of nonharvested trees
Primary forest products industry and industrial roundwood production, Michigan, 1969.
James E. Blyth; Allen H. Boelter
1971-01-01
Michigan loggers cut 173.8 million cubic feet of industrial roundwood products in 1969. Ninety percent was pulpwood and saw logs. Production is shifting from softwoods to hardwoods. The number of active primary wood-using mills declined rapidly from 1954 to 1969, but production per mill has expanded.
Cost of wetland protection using cable logging systems
Chris B. LeDoux; John E. Baumgras
1990-01-01
Forest managers, loggers, land-use planners, and other decision makers need an understanding of estimating the cost of protecting wetlands using cable logging systems to harvest timber products. Results suggest that protection costs can range from $244.75 to $489.50 per acre depending on the degree of protection desired.
40 CFR 49.4165 - Control equipment requirements.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., except for § 60.18(c)(2) and (f)(2) for those utility flares operated with an electronically controlled...) Equipped with one of the following: (A) A continuous burning pilot flame. (B) An electronically controlled... electronically controlled automatic igniter, such as a chart recorder, data logger or similar devices; (vi...
40 CFR 49.4165 - Control equipment requirements.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., except for § 60.18(c)(2) and (f)(2) for those utility flares operated with an electronically controlled...) Equipped with one of the following: (A) A continuous burning pilot flame. (B) An electronically controlled... electronically controlled automatic igniter, such as a chart recorder, data logger or similar devices; (vi...
Wireless sensor network for monitoring soil moisture and weather conditions
USDA-ARS?s Scientific Manuscript database
A wireless sensor network (WSN) was developed and deployed in three fields to monitor soil water status and collect weather data for irrigation scheduling. The WSN consists of soil-water sensors, weather sensors, wireless data loggers, and a wireless modem. Soil-water sensors were installed at three...
Soil moisture and plant canopy temperature sensing for irrigation application in cotton
USDA-ARS?s Scientific Manuscript database
A wireless sensor network was deployed in a cotton field to monitor soil water status for irrigation. The network included two systems, a Decagon system and a microcontroller-based system. The Decagon system consists of soil volumetric water-content sensors, wireless data loggers, and a central data...
Controlled-Release Microcapsules for Smart Coatings for Corrosion Applications
NASA Technical Reports Server (NTRS)
2008-01-01
Corrosion is a serious problem that has enormous costs and serious safety implications. Localized corrosion, such as pitting, is very dangerous and can cause catastrophic failures. The NASA Corrosion Technology Laboratory at Kennedy Space Center is developing a smart coating based on pH-sensitive microcapsules for corrosion applications. These versatile microcapsules are designed to be incorporated into a smart coating and deliver their core content when corrosion starts. Corrosion indication was the first function incorporated into the microcapsules. Current efforts are focused on incorporating the corrosion inhibition function through the encapsulation of corrosion inhibitors into water core and oil core microcapsules. Scanning electron microscopy (SEM) images of encapsulated corrosion inhibitors are shown.
Effects of space weather on high-latitude ground systems
NASA Astrophysics Data System (ADS)
Pirjola, Risto
Geomagnetically induced currents (GIC) in technological systems, such as power grids, pipelines, cables and railways, are a ground manifestation of space weather. The first GIC observations were already made in early telegraph equipment more than 150 years ago. In power networks, GIC may saturate transformers with possible harmful consequences extending even to a collapse of the whole system or to permanent damage of transformers. In pipelines, GIC and the associated pipe-to-soil voltages may enhance corrosion or disturb surveys associated with corrosion control. GIC are driven by the geoelectric field induced by a geomagnetic variation at the Earth’s surface. The electric and magnetic fields are primarily produced by ionospheric currents and secondarily affected by the ground conductivity. Of great importance is the auroral electrojet with other rapidly varying currents indicating that GIC are a particular high-latitude problem. In this paper, we summarize the GIC research done in Finland during about 25 years, and discuss the calculation of GIC in a given network. Special attention is paid to modelling a power system. It is shown that, when considering GIC at a site, it is usually sufficient to take account for a smaller grid in the vicinity of the particular site. Modelling GIC also provides a basis for developing forecasting and warning methods of GIC.
Effects of space weather on high-latitude ground systems
NASA Astrophysics Data System (ADS)
Pirjola, R.
Geomagnetically induced currents (GIC) in technological systems, such as power grids, pipelines, cables and railways, are a ground manifestation of space weather. The first GIC observations were already made in early telegraph equipment about 150 years ago. In power networks, GIC may saturate transformers with possible harmful consequences extending from harmonics in the electricity to excessive reactive power demands and even to a collapse of the system or to damage of transformers. In pipelines, GIC and the associated pipe-to-soil voltages may enhance corrosion or disturb corrosion control. GIC are driven by the geoelectric field induced by a geomagnetic variation at the Earth's surface. The electric and magnetic fields are primarily produced by ionospheric currents and secondarily affected by the ground conductivity. Of great importance is the auroral electrojet with other rapidly-varying currents indicating that GIC are a particular high latitude problem. Thus, a lot of GIC research has been done in North America and Scandinavia. For example in Finland, GIC have been studied for about 25 years in collaboration between scientists and industry. A scientific challenge in GIC research today is to investigate the ionospheric events that produce the largest geoelectric fields and GIC. Forecasting purposes will require fast methods of calculating the geoelectric field.
Gamma radiation induces hydrogen absorption by copper in water
NASA Astrophysics Data System (ADS)
Lousada, Cláudio M.; Soroka, Inna L.; Yagodzinskyy, Yuriy; Tarakina, Nadezda V.; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A.; Jonsson, Mats
2016-04-01
One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.
A quantitative study on magnesium alloy stent biodegradation.
Gao, Yuanming; Wang, Lizhen; Gu, Xuenan; Chu, Zhaowei; Guo, Meng; Fan, Yubo
2018-06-06
Insufficient scaffolding time in the process of rapid corrosion is the main problem of magnesium alloy stent (MAS). Finite element method had been used to investigate corrosion of MAS. However, related researches mostly described all elements suffered corrosion in view of one-dimensional corrosion. Multi-dimensional corrosions significantly influence mechanical integrity of MAS structures such as edges and corners. In this study, the effects of multi-dimensional corrosion were studied using experiment quantitatively, then a phenomenological corrosion model was developed to consider these effects. We implemented immersion test with magnesium alloy (AZ31B) cubes, which had different numbers of exposed surfaces to analyze differences of dimension. It was indicated that corrosion rates of cubes are almost proportional to their exposed-surface numbers, especially when pitting corrosions are not marked. The cubes also represented the hexahedron elements in simulation. In conclusion, corrosion rate of every element accelerates by increasing corrosion-surface numbers in multi-dimensional corrosion. The damage ratios among elements with the same size are proportional to the ratios of corrosion-surface numbers under uniform corrosion. The finite element simulation using proposed model provided more details of changes of morphology and mechanics in scaffolding time by removing 25.7% of elements of MAS. The proposed corrosion model reflected the effects of multi-dimension on corrosions. It would be used to predict degradation process of MAS quantitatively. Copyright © 2018 Elsevier Ltd. All rights reserved.
Sui, Yiyong; Sun, Chong; Sun, Jianbo; Pu, Baolin; Ren, Wei; Zhao, Weimin
2017-06-09
The stability of an electrodeposited nanocrystalline Ni-based alloy coating in a H₂S/CO₂ environment was investigated by electrochemical measurements, weight loss method, and surface characterization. The results showed that both the cathodic and anodic processes of the Ni-based alloy coating were simultaneously suppressed, displaying a dramatic decrease of the corrosion current density. The corrosion of the Ni-based alloy coating was controlled by H₂S corrosion and showed general corrosion morphology under the test temperatures. The corrosion products, mainly consisting of Ni₃S₂, NiS, or Ni₃S₄, had excellent stability in acid solution. The corrosion rate decreased with the rise of temperature, while the adhesive force of the corrosion scale increased. With the rise of temperature, the deposited morphology and composition of corrosion products changed, the NiS content in the corrosion scale increased, and the stability and adhesive strength of the corrosion scale improved. The corrosion scale of the Ni-based alloy coating was stable, compact, had strong adhesion, and caused low weight loss, so the corrosion rates calculated by the weight loss method cannot reveal the actual oxidation rate of the coating. As the corrosion time was prolonged, the Ni-based coating was thinned while the corrosion scale thickened. The corrosion scale was closely combined with the coating, but cannot fully prevent the corrosive reactants from reaching the substrate.
NASA Technical Reports Server (NTRS)
Zollars, G. F.
1979-01-01
This bibliography cites 118 articles from the international literature concerning corrosion characteristics of nickel alloys. Articles dealing with corrosion resistance, corrosion tests, intergranular corrosion, oxidation resistance, and stress corrosion cracking of nickel alloys are included.
Stress Corrosion-Cracking and Corrosion Fatigue Impact of IZ-C17+ Zinc Nickel on 4340 Steel
2017-05-17
REPORT NO: NAWCADPAX/TIM-2016/189 STRESS CORROSION-CRACKING AND CORROSION FATIGUE IMPACT OF IZ-C17+ ZINC-NICKEL ON 4340 STEEL by...CORROSION-CRACKING AND CORROSION FATIGUE IMPACT OF IZ-C17+ ZINC-NICKEL ON 4340 STEEL by Craig Matzdorf Charles Lei Matt Stanley...5a. CONTRACT NUMBER STRESS CORROSION-CRACKING AND CORROSION FATIGUE IMPACT OF IZ-C17+ ZINC-NICKEL ON 4340 STEEL 5b. GRANT NUMBER 5c. PROGRAM
DOE Office of Scientific and Technical Information (OSTI.GOV)
Atrens, Andrej; Song, Guang -Ling; Liu, Ming
2015-01-07
This paper provides a review of recent developments in the field of Mg corrosion and puts those into context. This includes considerations of corrosion manifestations, material influences, surface treatment, anodization, coatings, inhibition, biodegradable medical applications, stress corrosion cracking, flammability, corrosion mechanisms for HP Mg, critical evaluation of corrosion mechanisms, and concluding remarks. There has been much research recently, and much research continues in this area. In conclusion, this is expected to produce significantly better, more-corrosion-resistant Mg alloys.
Simulation on the steel galvanic corrosion and acoustic emission
NASA Astrophysics Data System (ADS)
Yu, Yang; Shi, Xin; Yang, Ping
2015-12-01
Galvanic corrosion is a very destructive localized corrosion. The research on galvanic corrosion could determine equipment corrosion and prevent the accidents occurrence. Steel corrosion had been studied by COMSOL software with mathematical modeling. The galvanic corrosion of steel-aluminum submerged into 10% sodium chloride solution had been on-line detected by PIC-2 acoustic emission system. The results show that the acoustic emission event counts detected within unit time can qualitative judge galvanic corrosion rate and further erosion trend can be judged by the value changes.
NASA Astrophysics Data System (ADS)
Kurniawan, Budi Agung; Pratiwi, Vania Mitha; Ahmadi, Nafi'ul Fikri
2018-04-01
Corrosion become major problem in most industries. In the oil and gas company, corrosion occurs because of reaction between steel and chemical species inside crude oil. Crude oil or nature gas provide corrosive species, such as CO2, O2, H2S and so on. Fluid containing CO2 gas causes CO2 corrosion which attack steel as well as other corrosion phenomena. This CO2 corrosion commonly called as sweet environment and produce FeCO3 as corrosion products. Fluid flow factor in pipelines during the oil and gas transportation might increase the rate of corrosion itself. Inhibitor commonly use used as corrosion protection because its simplicity in usage. Nowadays, organic inhibitor become main issue in corrosion protection because of biodegradable, low cost, and environmental friendly. This research tried to use tobacco leaf extract as organic inhibitor to control corrosion in CO2 environment. The electrolyte solution used was 3.5% NaCl at pH 4 and pH 7. Weight loss test results showed that the lowest corrosion rate was reach at 132.5 ppm inhibitor, pH 7 and rotational speed of 150 rpm with corrosion rate of 0.091 mm/y. While at pH 4, the lowest corrosion rate was found at rotational speed of 150 rpm with inhibitor concentration of 265 ppm and corrosion rate of 0.327 mm/y. FTIR results indicate the presence of nicotine functional groups on the steel surface. However, based on corrosion rate, it is believed that corrosion occurs, and FeCO3 was soluble in electrolyte. Tobacco leaf extract inhibitors worked by a physisorption mechanism, where tobacco inhibitors formed thin layer on the steel surface.
Corrosion and Corrosion Control in Light Water Reactors
NASA Astrophysics Data System (ADS)
Gordon, Barry M.
2013-08-01
Serious corrosion problems have plagued the light water reactor (LWR) industry for decades. The complex corrosion mechanisms involved and the development of practical engineering solutions for their mitigation will be discussed in this article. After a brief overview of the basic designs of the boiling water reactor (BWR) and pressurized water reactor (PWR), emphasis will be placed on the general corrosion of LWR containments, flow-accelerated corrosion of carbon steel components, intergranular stress corrosion cracking (IGSCC) in BWRs, primary water stress corrosion cracking (PWSCC) in PWRs, and irradiation-assisted stress corrosion cracking (IASCC) in both systems. Finally, the corrosion future of both plants will be discussed as plants extend their period of operation for an additional 20 to 40 years.
Martin, Holly J.; Horstemeyer, M. F.; Wang, Paul T.
2010-01-01
The understanding of how corrosion affects magnesium alloys is of utmost importance as the automotive and aerospace industries have become interested in the use of these lightweight alloys. However, the standardized salt-spray test does not produce adequate corrosion results when compared with field data, due to the lack of multiple exposure environments. This research explored four test combinations through three sets of cycles to determine how the corrosion mechanisms of pitting, intergranular corrosion, and general corrosion were affected by the environment. Of the four test combinations, Humidity-Drying was the least corrosive, while the most corrosive test condition was Salt Spray-Humidity-Drying.more » The differences in corrosivity of the test conditions are due to the various reactions needed to cause corrosion, including the presence of chloride ions to cause pit nucleation, the presence of humidity to cause galvanic corrosion, and the drying phase which trapped chloride ions beneath the corrosion by-products.« less
NASA Astrophysics Data System (ADS)
Zhang, Dazheng; Gao, Xiuhua; Su, Guanqiao; Du, Linxiu; Liu, Zhenguang; Hu, Jun
2017-05-01
The corrosion behavior of low-C medium-Mn steel in simulated marine immersion and splash zone environment was studied by static immersion corrosion experiment and wet-dry cyclic corrosion experiment, respectively. Corrosion rate, corrosion products, surface morphology, cross-sectional morphology, elemental distribution, potentiodynamic polarization curves and electrochemical impedance spectra were used to elucidate the corrosion behavior of low-C medium-Mn steel. The results show that corrosion rate in immersion zone is much less than that in splash zone owing to its relatively mild environment. Manganese compounds are detected in the corrosion products and only appeared in splash zone environment, which can deteriorate the protective effect of rust layer. With the extension of exposure time, corrosion products are gradually transformed into dense and thick corrosion rust from the loose and porous one in these two environments. But in splash zone environment, alloying elements of Mn appear significant enrichment in the rust layer, which decrease the corrosion resistance of the steel.
Corrosion and corrosion prevention in gas turbines
NASA Technical Reports Server (NTRS)
Mom, A. J. A.; Kolkman, H. J.
1985-01-01
The conditions governing the corrosion behavior in gas turbines are surveyed. Factors such as temperature, relative humidity, the presence of sulfur and nitrogen dioxide, and fuel quality are discussed. Electromechanical corrosion at relatively low temperature in compressors; oxidation; and hot corrosion (sulfidation) at high temperature in turbines are considered. Corrosion prevention by washing and rinsing, fueld additives, and corrosion resistant materials and coatings are reviewed.
NASA Technical Reports Server (NTRS)
Calle, Luz Marina
2015-01-01
The marine environment at NASAs Kennedy Space Center (KSC) has been documented by ASM International (formerly American Society for Metals) as the most corrosive in North America. With the introduction of the Space Shuttle in 1981, the already highly corrosive conditions at the launch pads were rendered even more severe by the highly corrosive hydrochloric acid (HCl) generated by the solid rocket boosters (SRBs). Numerous failures at the launch pads are caused by corrosion. The structural integrity of ground infrastructure and flight hardware is critical to the success, safety, cost, and sustainability of space missions. NASA has over fifty years of experience dealing with unexpected failures caused by corrosion and has developed expertise in corrosion control in the launch and other environments. The Corrosion Technology Laboratory at KSC evolved, from what started as an atmospheric exposure test site near NASAs launch pads, into a capability that provides technical innovations and engineering services in all areas of corrosion for NASA, external partners, and customers.This paper provides a chronological overview of NASAs role in anticipating, managing, and preventing corrosion in highly corrosive environments. One important challenge in managing and preventing corrosion involves the detrimental impact on humans and the environment of what have been very effective corrosion control strategies. This challenge has motivated the development of new corrosion control technologies that are more effective and environmentally friendly. Strategies for improved corrosion protection and durability can have a huge impact on the economic sustainability of human spaceflight operations.
Sui, Yiyong; Sun, Chong; Sun, Jianbo; Pu, Baolin; Ren, Wei; Zhao, Weimin
2017-01-01
The stability of an electrodeposited nanocrystalline Ni-based alloy coating in a H2S/CO2 environment was investigated by electrochemical measurements, weight loss method, and surface characterization. The results showed that both the cathodic and anodic processes of the Ni-based alloy coating were simultaneously suppressed, displaying a dramatic decrease of the corrosion current density. The corrosion of the Ni-based alloy coating was controlled by H2S corrosion and showed general corrosion morphology under the test temperatures. The corrosion products, mainly consisting of Ni3S2, NiS, or Ni3S4, had excellent stability in acid solution. The corrosion rate decreased with the rise of temperature, while the adhesive force of the corrosion scale increased. With the rise of temperature, the deposited morphology and composition of corrosion products changed, the NiS content in the corrosion scale increased, and the stability and adhesive strength of the corrosion scale improved. The corrosion scale of the Ni-based alloy coating was stable, compact, had strong adhesion, and caused low weight loss, so the corrosion rates calculated by the weight loss method cannot reveal the actual oxidation rate of the coating. As the corrosion time was prolonged, the Ni-based coating was thinned while the corrosion scale thickened. The corrosion scale was closely combined with the coating, but cannot fully prevent the corrosive reactants from reaching the substrate. PMID:28772995
In-situ monitoring of undercoating corrosion damage by Direct Optical Interrogation (DOI)
NASA Astrophysics Data System (ADS)
Lopez-Garrity, Meng
An approach referred to as "Direct Optical Interrogation" (DOI) has been developed as an extension of the thin film pitting approach developed and used by Frankel and others. Samples were prepared by depositing Al and Al-Cu alloy metallizations about 800 nm thick on glass substrates. These metallizations were then coated with various coatings and coating systems. Samples were introduced to aggressive environments and the progression of corrosion of the metallization under the coating was monitored in situ using low power videography. Because metallizations were thin, corrosion quickly penetrated through the metal layer to the glass substrate and then spread laterally. Measurement of the lateral spread of corrosion enabled non-electrochemical assessment of the corrosion kinetics. In Al-Cu thin films, both aged and as-deposited, corrosion sites are irregularly shaped because there is not enough cathodic current to propagate the entire corrosion site margin at equal rates. In a number of cases, corrosion propagates with a filamentary morphology resembling filiform corrosion. Cu played a strong role in determining under coating corrosion morphology and growth kinetics in experiments with Al-Cu thin films substrates. As-deposited Al-Cu metallizations were more corrosion resistant than aged metallization and both were more corrosion resistant than pure Al. Cu-rich dendrites were formed on the corrosion front. Corrosion rate (current density) was calculated using Faraday's law by collecting corrosion site perimeter and bottom area. Systematic exploration of the effects of a chromate and chromate-free conversion coatings, chromate and chromate-free primer coatings and the presence or absence of a polyurethane topcoat confirmed the extraordinary corrosion protection by chromates. A commercial praseodymium-pigmented primer coating was not particularly effective in retarding undercoating corrosion site growth unless paired with a chromate conversion coating. The presence of a topcoat dramatically reduces undercoating corrosion and masks many deficiencies of a conversion coating or primer. DOI was used to compare undercoating corrosion that developed due to exposure in ASTM B117, ASTM G85-A5 and outdoor environments. Similar corrosion morphologies developed in ASTM B117 and static immersion exposures. A single and stable corrosions site nucleated and propagated with a filamentary morphology. In general, salt spray exposure was more aggressive than static immersion. ASTM G85-A5 exposure produced different corrosion morphologies. Corrosion sites were round rather than filamentary. Massive nucleation of small corrosion sites across the whole surface also occurred. ASTM G85 environment was mild compared with the ASTM B117 and static immersion exposures. In outdoor exposure testing carried out for 5 months, no signs of corrosion was observed. To assess the extent to which oxygen reduction occurring on the coated surface supported corrosion site growth, a universal pH indicator was added to agar gels or PVB coatings applied on top of metallizations. Color changes indicating pH changes associated with local alkalization or acidification due to local cell action were assessed visually. Overall, the evidence is consistent with the idea that both hydrogen reduction and oxygen reduction support local corrosion site growth. In practical embodiments of corrosion protection, every effort should be made to restrict oxygen reduction to slow corrosion growth rates.
Virtual Instrumentation Corrosion Controller for Natural Gas Pipelines
NASA Astrophysics Data System (ADS)
Gopalakrishnan, J.; Agnihotri, G.; Deshpande, D. M.
2012-12-01
Corrosion is an electrochemical process. Corrosion in natural gas (methane) pipelines leads to leakages. Corrosion occurs when anode and cathode are connected through electrolyte. Rate of corrosion in metallic pipeline can be controlled by impressing current to it and thereby making it to act as cathode of corrosion cell. Technologically advanced and energy efficient corrosion controller is required to protect natural gas pipelines. Proposed virtual instrumentation (VI) based corrosion controller precisely controls the external corrosion in underground metallic pipelines, enhances its life and ensures safety. Designing and development of proportional-integral-differential (PID) corrosion controller using VI (LabVIEW) is carried out. When the designed controller is deployed at field, it maintains the pipe to soil potential (PSP) within safe operating limit and not entering into over/under protection zone. Horizontal deployment of this technique can be done to protect all metallic structure, oil pipelines, which need corrosion protection.
49 CFR 192.491 - Corrosion control records.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...
49 CFR 192.491 - Corrosion control records.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...
49 CFR 192.491 - Corrosion control records.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 3 2014-10-01 2014-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...
49 CFR 192.491 - Corrosion control records.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 3 2013-10-01 2013-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...
49 CFR 192.491 - Corrosion control records.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 3 2012-10-01 2012-10-01 false Corrosion control records. 192.491 Section 192.491... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.491 Corrosion... detail to demonstrate the adequacy of corrosion control measures or that a corrosive condition does not...
Summary of the Sixth Persh Workshop: Corrosion Policy Guiding Science and Technology
2016-01-01
mitigating corrosion. Corrosion affects military readiness, so corrosion prevention and control (CPC) have a high priority for the DOD since CPC is a...resulting in high -cost repairs. Corrosion mitigation is thus a key cost-effective approach for system maintainability and reduced life cycle costs. The... treatments . • Develop corrosion databases and corrosion models for predictive evaluation. Testing methods for realistic prediction of performance
Corrosion of titanium: Part 1: aggressive environments and main forms of degradation.
Prando, Davide; Brenna, Andrea; Diamanti, Maria Vittoria; Beretta, Silvia; Bolzoni, Fabio; Ormellese, Marco; Pedeferri, MariaPia
2017-11-11
Titanium has outstanding corrosion resistance due to the external natural oxide protective layer formed when it is exposed to an aerated environment. Despite this, titanium may suffer different forms of corrosion in severe environments: uniform corrosion, pitting and crevice corrosion, hydrogen embrittlement, stress-corrosion cracking, fretting corrosion and erosion. In this first review, forms of corrosion affecting titanium are analyzed based on a wide literature review. For each form of corrosion, the mechanism and most severe environment are reported according to the current understanding.In the second part, this review will address the possible surface treatments that can increase corrosion resistance on commercially pure titanium: Electrochemical anodizing, thermal oxidation, chemical oxidation and bulk treatments such as alloying will be considered, highlighting the advantages of each technique.
Corrosion Behavior of Ceramic Cup of Blast Furnace Hearth by Liquid Iron and Slag
NASA Astrophysics Data System (ADS)
Li, Yanglong; Cheng, Shusen; Wang, Zhifeng
2016-10-01
Three kinds of sample bricks of ceramic cups for blast furnace hearth were studied by dynamic corrosion tests based on different corrosion systems, i.e., liquid iron system, liquid slag system and liquid iron-slag system. Considering the influence of temperature and sample rotational speed, the corrosion profiles and mass loss of the samples were analyzed. In addition, the microstructure of the corroded samples was observed by optical microscope (OM) and scanning electron microscope (SEM). It was found that the corrosion profiles could be divided into iron corrosion region, slag corrosion region and iron-slag corrosion region via corrosion degree after iron-slag corrosion experiment. The most serious corrosion occurred in iron-slag corrosion region. This is due to Marangoni effect, which promotes a slag film formed between liquid iron and ceramic cup and results in local corrosion. The corrosion of the samples deepened with increasing temperature of liquid iron and slag from 1,623 K to 1,823 K. The variation of slag composition had greater influence on the erosion degree than that of rotational speed in this experiment. Taking these results into account the ceramic cup composition should be close to slag composition to decrease the chemical reaction. A microporous and strong material should be applied for ceramic cup.
Uniform Corrosion and General Dissolution of Aluminum Alloys 2024-T3, 6061-T6, and 7075-T6
NASA Astrophysics Data System (ADS)
Huang, I.-Wen
Uniform corrosion and general dissolution of aluminum alloys was not as well-studied in the past, although it was known for causing significant amount of weight loss. This work comprises four chapters to understand uniform corrosion of aluminum alloys 2024-T3, 6061-T6, and 7075-T6. A preliminary weight loss experiment was performed for distinguishing corrosion induced weight loss attributed to uniform corrosion and pitting corrosion. The result suggested that uniform corrosion generated a greater mass loss than pitting corrosion. First, to understand uniform corrosion mechanism and kinetics in different environments, a series of static immersion tests in NaCl solutions were performed to provide quantitative measurement of uniform corrosion. Thereafter, uniform corrosion development as a function of temperature, pH, Cl-, and time was investigated to understand the influence of environmental factors. Faster uniform corrosion rate has been found at lower temperature (20 and 40°C) than at higher temperature (60 and 80°C) due to accelerated corrosion product formation at high temperatures inhibiting corrosion reactions. Electrochemical tests including along with scanning electron microscopy (SEM) were utilized to study the temperature effect. Second, in order to further understand the uniform corrosion influence on pit growth kinetics, a long term exposures for 180 days in both immersion and ASTM-B117 test were performed. Uniform corrosion induced surface recession was found to have limited impact on pit geometry regardless of exposure methods. It was also found that the competition for limited cathodic current from uniform corrosion the primary rate limiting factor for pit growth. Very large pits were found after uniform corrosion growth reached a plateau due to corrosion product coverage. Also, optical microscopy and focused ion beam (FIB) imaging has provided more insights of distinctive pitting geometry and subsurface damages found from immersion samples and B117 samples. Although uniform corrosion was studied in various electrolytes, the pH impact was still difficult to discern due to ongoing cathodic reactions that changed electrolyte pH with time. Therefore, buffered pH electrolytes with pH values of 3, 5, 8, and 10 were prepared static immersion tests. Electrochemical experiments were performed in each buffered pH conditions for understanding corrosion mechanisms. Uniform corrosion was found exhibiting higher corrosion rate in buffered acidic and alkaline electrolytes due to pH- and temperature-dependent corrosion product precipitation. Observations were supported by electrochemical, SEM, and EDS observations. Due to the complexity of corrosion data, a reliable corrosion prediction based on empirical observations could be challenging. Artificial neural network (ANN) modeling was used for corrosion data pattern recognition by mimicking human neural network systems. Predictive models were developed based on corrosion data acquired in this study. The model was adaptable through iteratively update its prediction by error minimization during the training phase. Trained ANN model can predict uniform corrosion successfully. In addition to ANN, fuzzy curve analysis was utilized to rank the influence of each input (temperature, pH, Cl-, and time). For example, temperature and pH were found to be the most influential parameters to uniform corrosion. This information can provide feedback for ANN improvement, also known as "data pruning".
Hot corrosion of the B2 nickel aluminides
NASA Technical Reports Server (NTRS)
Ellis, David L.
1993-01-01
The hot corrosion behavior of the B2 nickel aluminides was studied to determine the inherent hot corrosion resistance of the beta nickel aluminides and to develop a mechanism for the hot corrosion of the beta nickel aluminides. The effects of the prior processing of the material, small additions of zirconium, stoichiometry of the materials, and preoxidation of the samples were also examined. Additions of 2, 5, and 15 w/o chromium were used to determine the effect of chromium on the hot corrosion of the beta nickel aluminides and the minimum amount of chromium necessary for good hot corrosion resistance. The results indicate that the beta nickel aluminides have inferior inherent hot corrosion resistance despite their excellent oxidation resistance. Prior processing and zirconium additions had no discernible effect on the hot corrosion resistance of the alloys. Preoxidation extended the incubation period of the alloys only a few hours and was not considered to be an effective means of stopping hot corrosion. Stoichiometry was a major factor in determining the hot corrosion resistance of the alloys with the higher aluminum alloys having a definitely superior hot corrosion resistance. The addition of chromium to the alloys stopped the hot corrosion attack in the alloys tested. From a variety of experimental results, a complex hot corrosion mechanism was proposed. During the early stages of the hot corrosion of these alloys the corrosion is dominated by a local sulphidation/oxidation form of attack. During the intermediate stages of the hot corrosion, the aluminum depletion at the surface leads to a change in the oxidation mechanism from a protective external alumina layer to a mixed nickel-aluminum spinel and nickel oxide that can occur both externally and internally. The material undergoes extensive cracking during the later portions of the hot corrosion.
NASA Technical Reports Server (NTRS)
Calle, Luz Marina
2014-01-01
Corrosion is the degradation of a material that results from its interaction with the environment. The marine environment at NASAs Kennedy Space Center (KSC) has been documented by ASM International (formerly American Society for Metals) as the most corrosive in the United States. With the introduction of the Space Shuttle in 1981, the already highly corrosive conditions at the launch pads were rendered even more severe by the 70 tons of highly corrosive hydrochloric acid that were generated by the solid rocket boosters. Numerous failures at the launch pads are caused by corrosion.The structural integrity of ground infrastructure and flight hardware is critical to the success, safety, cost, and sustainability of space missions. As a result of fifty years of experience with launch and ground operations in a natural marine environment that is highly corrosive, NASAs Corrosion Technology Laboratory at KSC is a major source of corrosion control expertise in the launch and other environments. Throughout its history, the Laboratory has evolved from what started as an atmospheric exposure facility near NASAs launch pads into a world-wide recognized capability that provides technical innovations and engineering services in all areas of corrosion for NASA and external customers.This presentation will provide a historical overview of the role of NASAs Corrosion Technology in anticipating, managing, and preventing corrosion. One important challenge in managing and preventing corrosion involves the detrimental impact on humans and the environment of what have been very effective corrosion control strategies. This challenge has motivated the development of new corrosion control technologies that are more effective and environmentally friendly. Strategies for improved corrosion protection and durability can have a huge impact on the economic sustainability of human spaceflight operations.
Corrosion of RoHS-Compliant Surface Finishes in Corrosive Mixed Flowing Gas Environments
NASA Astrophysics Data System (ADS)
Hannigan, K.; Reid, M.; Collins, M. N.; Dalton, E.; Xu, C.; Wright, B.; Demirkan, K.; Opila, R. L.; Reents, W. D.; Franey, J. P.; Fleming, D. A.; Punch, J.
2012-03-01
Recently, the corrosion resistance of printed wiring board (PWB) finishes has generated considerable interest due to field failures observed in various parts of the world. This study investigates the corrosion issues associated with the different lead-free PWB surface finishes. Corrosion products on various PWB surface finishes generated in mixed flowing gas (MFG) environments were studied, and analysis techniques such as scanning electron microscopy, energy-dispersive x-ray, x-ray diffraction, focused ion beam, and scanning Auger microscopy were used to quantify the corrosion layer thickness and determine the composition of corrosion products. The corrosion on organic solderability preservative samples shows similar corrosion products to bare copper and is mainly due to direct attack of copper traces by corrosive gases. The corrosion on electroless nickel immersion gold occurs primarily through the porosity in the film and is accelerated by the galvanic potential between gold and copper; similar results were observed on immersion silver. Immersion tin shows excellent corrosion resistance due to its inherent corrosion resistance in the MFG environment as well as the opposite galvanic potential between tin and copper compared with gold or silver and copper.
NASA Astrophysics Data System (ADS)
Liu, Zhiguo; Yan, Guangyao; Mu, Zhitao; Li, Xudong
2018-01-01
The accelerated pitting corrosion test of 7B04 aluminum alloy specimen was carried out according to the spectrum which simulated airport environment, and the corresponding pitting corrosion damage was obtained and was defined through three parameters A and B and C which respectively denoted the corrosion pit surface length and width and corrosion pit depth. The ratio between three parameters could determine the morphology characteristics of corrosion pits. On this basis the stress concentration factor of typical corrosion pit morphology under certain load conditions was quantitatively analyzed. The research shows that the corrosion pits gradually incline to be ellipse in surface and moderate in depth, and most value of B/A and C/A lies in 1 between 4 and few maximum exceeds 4; The stress concentration factor Kf of corrosion pits is obviously affected by the its morphology, the value of Kf increases with corrosion pits depth increasement under certain corrosion pits surface geometry. Also, the value of Kf decreases with surface width increasement under certain corrosion pits depth. The research conclusion can set theory basis for corrosion fatigue life analysis of aircraft aluminum alloy structure.
pH Responsive Microcapsules for Corrosion Control
NASA Technical Reports Server (NTRS)
Calle, Luz Marina; Li, Wenyan; Muehlberg, Aaron; Boraas, Samuel; Webster, Dean; JohnstonGelling, Victoria; Croll, Stuart; Taylor, S Ray; Contu, Francesco
2008-01-01
The best coatings for corrosion protection provide not only barriers to the environment, but also a controlled release of a corrosion inhibitor, as demanded by the presence of corrosion or mechanical damage. NASA has developed pH sensitive microcapsules (patent pending) that can release their core contents when corrosion starts. The objectives of the research presented here were to encapsulate non-toxic corrosion inhibitors, to incorporate the encapsulated inhibitors into paint formulations, and to test the ability of the paints to control corrosion. Results showed that the encapsulated corrosion inhibitors, specifically Ce(NO3)3 , are effective to control corrosion over long periods of time when incorporated at relatively high pigment volume concentrations into a paint formulation.
Microstructural Aspects of Localized Corrosion Behavior of Mg Alloys
NASA Astrophysics Data System (ADS)
Chu, Peng-Wei
Combining high specific strength and unique electrochemical properties, magnesium (Mg) alloys are promising lightweight materials for various applications from automotive, consumer electronics, biomedical body implant, to battery electrodes. Engineering solutions such as coatings have enabled the use of Mg alloys, despite their intrinsic low corrosion resistance. Consequently, the fundamental mechanisms responsible for the unique localized corrosion behavior of bare Mg alloys, the associated abnormal hydrogen evolution response, and the relationships between corrosion behavior and alloy microstructure are still unsolved. This thesis aims to uncover the specificities of Mg corrosion and the roles of alloy chemistry and microstructure. To this end, multiscale site-specific microstructure characterization techniques, including in situ optical microscopy, scanning electron microscopy with focused ion beam milling, and transmission electron microscopy, combined with electrochemical analysis and hydrogen evolution rate monitoring, were performed on pure Mg and selected Mg alloys under free corrosion and anodic polarization, revealing key new information on the propagation mode of localized corrosion and the role of alloy microstructures, thereby confirming or disproving the validity of previously proposed corrosion models. Uniform surface corrosion film on Mg alloys immersed in NaCl solution consisted a bi-layered structure, with a porous Mg(OH)2 outer layer on top of a MgO inner layer. Presence of fine scale precipitates in Mg alloys interacted with the corrosion reaction front, reducing the corrosion rate and surface corrosion film thickness. Protruding hemispherical dome-like corrosion products, accompanied by growing hydrogen bubbles, formed on top of the impurity particles in Mg alloys by deposition of Mg(OH)2 via a microgalvanic effect. Localized corrosion on Mg alloys under both free immersion and anodic polarization was found to be governed by a common mechanism, with the corrosion front propagating laterally a few mum inside the alloy and underneath the surface corrosion film, with finger-like features aligned with (0001) Mg basal planes at the localized corrosion/alloy interface. Rising streams of hydrogen bubbles were found to follow the anodic dissolution of Mg and formation of Mg(OH)2 corrosion products at the propagating localized corrosion fronts. Alloying elements segregation to the grain boundaries showed the ability to stop localized corrosion propagation momentarily. By revealing the microstructure of corrosion features on Mg alloys, a descriptive model was proposed. Relationships between the corrosion behavior and alloy microstructures were also identified. This microscopic information can serve as a guideline for future development of Mg alloys by tailoring the microstructure to achieve proper corrosion responses for applications under different environments.
Corrosion and fatigue of surgical implants
NASA Technical Reports Server (NTRS)
Lisagor, W. B.
1975-01-01
Implants for the treatment of femoral fractures, mechanisms leading to the failure or degradation of such structures, and current perspectives on surgical implants are discussed. Under the first heading, general usage, materials and procedures, environmental conditions, and laboratory analyses of implants after service are considered. Corrosion, crevice corrosion, stress corrosion cracking, intergranular corrosion, pitting corrosion, fatigue, and corrosion fatigue are the principal degradation mechanisms described. The need for improvement in the reliability of implants is emphasized.
49 CFR 195.589 - What corrosion control information do I have to maintain?
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...
49 CFR 195.589 - What corrosion control information do I have to maintain?
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...
49 CFR 195.589 - What corrosion control information do I have to maintain?
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 3 2012-10-01 2012-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...
49 CFR 195.589 - What corrosion control information do I have to maintain?
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 3 2013-10-01 2013-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...
49 CFR 195.589 - What corrosion control information do I have to maintain?
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 3 2014-10-01 2014-10-01 false What corrosion control information do I have to... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.589 What corrosion control... sufficient detail to demonstrate the adequacy of corrosion control measures or that corrosion requiring...
NASA Technical Reports Server (NTRS)
Pearman, Benjamin Pieter; Calle, Luz M.
2015-01-01
This poster presents the results obtained from experiments designed to evaluate the release properties, as well as the corrosion inhibition effectiveness, of several encapsulated corrosion inhibitors. Microencapsulation has been used in the development of environmentally friendly multifunctional smart coatings. This technique enables the incorporation of autonomous corrosion detection, inhibition and self-healing functionalities into many commercially available coating systems. Select environmentally friendly corrosion inhibitors were encapsulated in organic and inorganic pH-sensitive microparticles and their release in basic solutions was studied. The release rate results showed that the encapsulation can be tailored from fast, for immediate corrosion protection, to slow, which will provide continued long-term corrosion protection. The incorporation of several corrosion inhibitor release profiles into a coating provides effective corrosion protection properties. To investigate the corrosion inhibition efficiency of the encapsulated inhibitors, electrochemical techniques were used to obtain corrosion potential, polarization curve and polarization resistance data. These measurements were performed using the free as well as the encapsulated inhibitors singly or in combinations. Results from these electrochemical tests will be compared to those obtained from weight loss and other accelerated corrosion experiments.
Evaluation of bridge cables corrosion using acoustic emission technique
NASA Astrophysics Data System (ADS)
Li, Dongsheng; Ou, Jinping
2010-04-01
Owing to the nature of the stress, corrosion of bridge cable may result in catastrophic failure of the structure. However, using electrochemical techniques isn't fully efficient for the detection and control on line of the corrosion phenomenon. A non-destructive testing method based on acoustic emission technique monitoring bridge cable corrosion was explored. The steel strands were placed at room temperature in 5% NaCl solution. Acoustic emission (AE) characteristic parameters were recorded in the whole corrosion experiment process. Based on the plot of cumulated acoustic activity, the bridge cables corrosion included three stages. It can be clearly seen that different stages have different acoustic emission signal characteristics. The AE characteristic parameters would be increased with cables corrosion development. Finally, the bridge cables corrosion experiment with different stress state and different corrosion environment was performed. The results shows that stress magnitude only affects the bridge cable failure time, however, the AE characteristic parameters value has changed a little. It was verified that AE technique can be used to detect the bridge cable early corrosion, investigating corrosion developing trend, and in monitoring and evaluating corrosion damages.
Chem I Supplement: Corrosion: A Waste of Energy.
ERIC Educational Resources Information Center
Journal of Chemical Education, 1979
1979-01-01
This article, intended for secondary school chemistry students, discusses the corrosion of metals. The discussion includes: (1) thermodynamic aspects of corrosion; (2) electrochemical aspects of corrosion; and (3) inhibition of corrosion processes. (HM)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kardash, N.V.; Egorov, V.V.; Forman, A.Y.
1986-11-01
The purpose of the present study is to ascertain the effectiveness of familiar additives and oil-soluble inhibitors under conditions of acid corrosion in comparison with their rapid action and waterreplacement efficiency, and the capacity to inhibit an electrolyte that forms in the oils, to protect against electrochemical corrosion, especially from pitting, and to reduce the mechanical-corrosion forms of wear. Characteristics of several oil-soluble corrosion inhibitors and the effectiveness of the oil-soluble inhibitors are shown. The additives M, ALOP, and MONIKA are most effective under fretting-corrosion conditions. It is shown that only the combined additives and compositions that provide for metalmore » protection in both acid and neutral media are sufficiently effective in preventing corrosion cracking, fatigue, corrosion fatigue and corrosion fretting.« less
Environmentally Friendly Coating Technology for Autonomous Corrosion Control
NASA Technical Reports Server (NTRS)
Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Johnsey, Marissa N.; Jolley, Scott T.; Pearman, Benjamin P.; Zhang, Xuejun; Fitzpatrick, Lilliana; Gillis, Mathew; Blanton, Michael;
2016-01-01
This work concerns the development of environmentally friendly encapsulation technology, specifically designed to incorporate corrosion indicators, inhibitors, and self-healing agents into a coating, in such a way that the delivery of the indicators and inhibitors is triggered by the corrosion process, and the delivery of self-healing agents is triggered by mechanical damage to the coating. Encapsulation of the active corrosion control ingredients allows the incorporation of desired autonomous corrosion control functions such as: early corrosion detection, hidden corrosion detection, corrosion inhibition, and self-healing of mechanical damage into a coating. The technology offers the versatility needed to include one or several corrosion control functions into the same coating.The development of the encapsulation technology has progressed from the initial proof-of-concept work, in which a corrosion indicator was encapsulated into an oil-core (hydrophobic) microcapsule and shown to be delivered autonomously, under simulated corrosion conditions, to a sophisticated portfolio of micro carriers (organic, inorganic, and hybrid) that can be used to deliver a wide range of active corrosion ingredients at a rate that can be adjusted to offer immediate as well as long-term corrosion control. The micro carriers have been incorporated into different coating formulas to test and optimize the autonomous corrosion detection, inhibition, and self-healing functions of the coatings. This paper provides an overview of progress made to date and highlights recent technical developments, such as improved corrosion detection sensitivity, inhibitor test results in various types of coatings, and highly effective self-healing coatings based on green chemistry.
Cui, Yong; Liu, Shuming; Smith, Kate; Hu, Hongying; Tang, Fusheng; Li, Yuhong; Yu, Kanghua
2016-10-01
Stainless steels generally have extremely good corrosion resistance, but are still susceptible to pitting corrosion. As a result, corrosion scales can form on the surface of stainless steel after extended exposure to aggressive aqueous environments. Corrosion scales play an important role in affecting water quality. These research results showed that interior regions of stainless steel corrosion scales have a high percentage of chromium phases. We reveal the morphology, micro-structure and physicochemical characteristics of stainless steel corrosion scales. Stainless steel corrosion scale is identified as a podiform chromite deposit according to these characteristics, which is unlike deposit formed during iron corrosion. A conceptual model to explain the formation and growth of stainless steel corrosion scale is proposed based on its composition and structure. The scale growth process involves pitting corrosion on the stainless steel surface and the consecutive generation and homogeneous deposition of corrosion products, which is governed by a series of chemical and electrochemical reactions. This model shows the role of corrosion scales in the mechanism of iron and chromium release from pitting corroded stainless steel materials. The formation of corrosion scale is strongly related to water quality parameters. The presence of HClO results in higher ferric content inside the scales. Cl - and SO 4 2- ions in reclaimed water play an important role in corrosion pitting of stainless steel and promote the formation of scales. Copyright © 2016. Published by Elsevier B.V.
The Inverse-Square Law with Data Loggers
ERIC Educational Resources Information Center
Bates, Alan
2013-01-01
The inverse-square law for the intensity of light received at a distance from a light source has been verified using various experimental techniques. Typical measurements involve a manual variation of the distance between a light source and a light sensor, usually by sliding the sensor or source along a bench, measuring the source-sensor distance…
Educational Electrical Appliance Power Meter and Logger
ERIC Educational Resources Information Center
Nunn, John
2013-01-01
The principles behind two different designs of inductive power meter are presented. They both make use of the microphone input of a computer which, together with a custom-written program, can record the instantaneous power of a domestic electrical appliance. The device can be built quickly and can be calibrated with reference to a known power…
Logging roads and log decks for wildlife habitat
William H. Healy
1989-01-01
Roads are essential to manage and use forest land. They can improve wildlife habitat and provide recreational opportunities. But roads are often controversial because they have so many different users-loggers, hikers, hunters, and off-road-vehicle drivers. Benefits to wildlife can be maximized and user conflicts minimized by careful planning and design. Decisions about...
Physiological and psychological impacts of extended work hours in logging operations
Dana Mitchell; Tom Gallagher
2007-01-01
A study was initiated in 2006 to develop an understanding of the considerations of using extended work hours in the logging industry in the southeastern United States. Through semistructured interviews, it was obvious that loggers were individually creating ways of successfully implementing extended working hours without understanding the impacts that extended working...
Skateboard/Longboard Speedometer Project
ERIC Educational Resources Information Center
Hare, Jonathan
2012-01-01
A simple, low-cost infrared LED speedometer is described that can be fitted to a skateboard, longboard or even a bicycle to measure speed. Notes on building, setting up and calibration are given. When used with a low-cost data logger, continuous measurements of speed can be made while out and about. The device forms an interesting science club…
Signal processing techniques were applied to high-resolution time series data obtained from conductivity loggers placed upstream and downstream of an oil and gas wastewater treatment facility along a river. Data was collected over 14-60 days. The power spectral density was us...
Conditioned Pupil Disposition, Autonomy, and Effective Use of ICT in Science Classrooms.
ERIC Educational Resources Information Center
Rodrigues, Susan
2003-01-01
Data from three projects (a CD-ROM of the periodic table, video animation on CD ROM, and data loggers) show how conditioned dispositions affect information/communications technology use. The projects demonstrate how students have been conditioned to work mindlessly in science classrooms, following the path of least cognitive demand and avoiding…
Using a Digital Video Camera to Study Motion
ERIC Educational Resources Information Center
Abisdris, Gil; Phaneuf, Alain
2007-01-01
To illustrate how a digital video camera can be used to analyze various types of motion, this simple activity analyzes the motion and measures the acceleration due to gravity of a basketball in free fall. Although many excellent commercially available data loggers and software can accomplish this task, this activity requires almost no financial…
Chris B. LeDoux
2006-01-01
Forest landowners, managers, loggers, land-use planners, and other decision/policy makers need to understand the opportunity cost associated with different levels of allowable management and required/voluntary protection in streamside management zones (SMZs). Four different logging technologies, two mature hardwood stands, three levels of streamside zone protection,...
Use of expert systems for integrated silvicultural planning
Chris B. LeDoux
1997-01-01
The use of silvicultural treatments in hardwood stands presents opportunities for increasing the growth and yield of quality sawtimber and enhancing the suitability of the site for use by numerous species of wildlife. Planners, loggers, and managers must consider multiple aspects of the ecosystem when making silvicultural decisions. In this paper we demonstrate an...
Coupled Oscillators: Interesting Experiments for High School Students
ERIC Educational Resources Information Center
Kodejška, C.; Lepil, O.; Sedlácková, H.
2018-01-01
This work deals with the experimental demonstration of coupled oscillators using simple tools in the form of mechanical coupled pendulums, magnetically coupled elastic strings or electromagnetic oscillators. For the evaluation of results the data logger Lab Quest Vernier and video analysis in the Tracker program were used. In the first part of…
ERIC Educational Resources Information Center
Bates, Alan
2015-01-01
Instruments or digital meters with data values visible on a seven-segment display can easily be found in the physics lab. Examples include multimeters, sound level meters, Geiger-Müller counters and electromagnetic field meters, where the display is used to show numerical data. Such instruments, without the ability to connect to computers or data…
Improving Attachments of Non-Invasive (Type III) Electronic Data Loggers to Cetaceans
2013-09-30
logged using a netbook and USB analog to digital converter. Initial testing of the SSSCup was conducted on a common dolphin (Delphinus delphis) cadaver...cell and five pressure sensors (four to measure internal cup pressure and one for atmospheric pressure). Sensor data are logged using a netbook and
Solving wood chip transport problems with computer simulation.
Dennis P. Bradley; Sharon A. Winsauer
1976-01-01
Efficient chip transport operations are difficult to achieve due to frequent and often unpredictable changes in distance to market, chipping rate, time spent at the mill, and equipment costs. This paper describes a computer simulation model that allows a logger to design an efficient transport system in response to these changing factors.
Implementation guide for turbidity threshold sampling: principles, procedures, and analysis
Jack Lewis; Rand Eads
2009-01-01
Turbidity Threshold Sampling uses real-time turbidity and river stage information to automatically collect water quality samples for estimating suspended sediment loads. The system uses a programmable data logger in conjunction with a stage measurement device, a turbidity sensor, and a pumping sampler. Specialized software enables the user to control the sampling...
Hardwood log supply: a broader perspective
Iris Montague; Adri Andersch; Jan Wiedenbeck; Urs Buehlmann
2015-01-01
At regional and state meetings we talk with others in our business about the problems we face: log exports, log quality, log markets, logger shortages, cash flow problems, the weather. These are familiar talking points and real and persistent problems. But what is the relative importance of these problems for log procurement in different regions of...
Technoeconomic analysis of conventional logging systems operating from stump to landing
Raymond L. Sarles; William G. Luppold; William G. Luppold
1986-01-01
Analyzes technical and economic factors for six conventional logging systems suitable for operation in eastern forests. Discusses financial risks and business implications for loggers investing in high-production, state-of-the-art logging systems. Provides logging contractors with information useful as a preliminary guide for selection of equipment and systems....
Changes in the Logging Labor Force
Charles H. Wolf; Jean W. Nolley
1977-01-01
Employment in the logging industry dropped 28 percent between 1950 and 1970, while output of industrial roundwood increased 31 percent. Today's loggers are older, better educated, and more skilled. A large proportion are self-employed, many work less than a full year, and a substantial number have incomes below the poverty level. Mechanization of timber harvesting...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-29
..., power reactors under construction, research and test reactors, agreement states, non-agreement states, as well as users of byproduct material (e.g. departments of health, medical centers, steel mills, well loggers, and radiographers.) 7. An estimate of the number of annual responses: 339. [[Page 71674...
A note on the collection and cleaning of water temperature data
Colin Sowder; E. Ashley Steel
2012-01-01
Inexpensive remote temperature data loggers have allowed for a dramatic increase of data describing water temperature regimes. This data is used in understanding the ecological functioning of natural riverine systems and in quantifying changes in these systems. However, an increase in the quantity of yearly temperature data necessitates complex data management,...
Developing a Webcam-Based Data Logger to Analyze Cosmic Rays in a Cloud Chamber
NASA Astrophysics Data System (ADS)
Nealon, Kelly; Bellis, Matt
2015-04-01
Muons from secondary cosmic rays provide students with an opportunity to interact with a natural phenomenon that relies both on special relativity and fairly sophisticated particle physics knowledge. In many physics departments, undergraduate students set up a pair of scintillators in coincidence to measure the rate of these muons and in some cases, measure their angular dependence, but this requires specialized and potentially expensive equipment. We have spent the past year formalizing a design of a cloud chamber that relies not on dry ice, but Peltier thermoelectric coolers, that can be built for about one hundred dollars worth of equipment. With this design we can see the tracks left by cosmic rays, however to turn it into a useful undergraduate physics lab requires some sort of data logger. This poster details our efforts to use an off-the-shelf webcam to trigger on the change in image when a cosmic ray track appears in the chamber. We use this to estimate the rate and angular dependence and compare our results to other measurements. The successes and limitations of this approach will be discussed.
Loggers and Forest Fragmentation: Behavioral Models of Road Building in the Amazon Basin
NASA Technical Reports Server (NTRS)
Arima, Eugenio Y.; Walker, Robert T.; Perz, Stephen G.; Caldas, Marcellus
2005-01-01
Although a large literature now exists on the drivers of tropical deforestation, less is known about its spatial manifestation. This is a critical shortcoming in our knowledge base since the spatial pattern of land-cover change and forest fragmentation, in particular, strongly affect biodiversity. The purpose of this article is to consider emergent patterns of road networks, the initial proximate cause of fragmentation in tropical forest frontiers. Specifically, we address the road-building processes of loggers who are very active in the Amazon landscape. To this end, we develop an explanation of road expansions, using a positive approach combining a theoretical model of economic behavior with geographic information systems (GIs) software in order to mimic the spatial decisions of road builders. We simulate two types of road extensions commonly found in the Amazon basin in a region: showing the fishbone pattern of fragmentation. Although our simulation results are only partially successful, they call attention to the role of multiple agents in the landscape, the importance of legal and institutional constraints on economic behavior, and the power of GIs as a research tool.
Landscape Utilisation, Animal Behaviour and Hendra Virus Risk.
Field, H E; Smith, C S; de Jong, C E; Melville, D; Broos, A; Kung, N; Thompson, J; Dechmann, D K N
2016-03-01
Hendra virus causes sporadic fatal disease in horses and humans in eastern Australia. Pteropid bats (flying-foxes) are the natural host of the virus. The mode of flying-fox to horse transmission remains unclear, but oro-nasal contact with flying-fox urine, faeces or saliva is the most plausible. We used GPS data logger technology to explore the landscape utilisation of black flying-foxes and horses to gain new insight into equine exposure risk. Flying-fox foraging was repetitious, with individuals returning night after night to the same location. There was a preference for fragmented arboreal landscape and non-native plant species, resulting in increased flying-fox activity around rural infrastructure. Our preliminary equine data logger study identified significant variation between diurnal and nocturnal grazing behaviour that, combined with the observed flying-fox foraging behaviour, could contribute to Hendra virus exposure risk. While we found no significant risk-exposing difference in individual horse movement behaviour in this study, the prospect warrants further investigation, as does the broader role of animal behaviour and landscape utilisation on the transmission dynamics of Hendra virus.
NASA Astrophysics Data System (ADS)
2010-09-01
WE RECOMMEND Enjoyable Physics Mechanics book makes learning more fun SEP Colorimeter Box A useful and inexpensive colorimeter for the classroom Pursuing Power and Light Account of the development of science in the 19th centuary SEP Bottle Rocket Launcher An excellent resource for teaching about projectiles GLE Datalogger GPS software is combined with a datalogger EDU Logger Remote datalogger has greater sensing abilities Logotron Insight iLog Studio Software enables datlogging, data analysis and modelling iPhone Apps Mobile phone games aid study of gravity WORTH A LOOK Physics of Sailing Book journeys through the importance of physics in sailing The Lightness of Being Study of what the world is made from LECTURE The 2010 IOP Schools and Colleges Lecture presents the physics of fusion WEB WATCH Planet Scicast pushes boundaries of pupil creativity
Effects of low-density feeding on elk–fetus contact rates on Wyoming feedgrounds
Creech, Tyler G.; Cross, Paul C.; Scurlock, Brandon M.; Maichak, Eric J.; Rogerson, Jared D.; Henningsen, John C.; Creel, Scott
2012-01-01
High seroprevalance for Brucella abortus among elk on Wyoming feedgrounds suggests that supplemental feeding may influence parasite transmission and disease dynamics by altering the rate at which elk contact infectious materials in their environment. We used proximity loggers and video cameras to estimate rates of elk-to-fetus contact (the primary source of brucellosis transmission) during winter supplemental feeding. We compared contact rates during high-density and low-density (LD) feeding treatments that provided the same total amount of food distributed over different areas. Low-density feeding led to >70% reductions in total number of contacts and number of individuals contacting a fetus. Proximity loggers and video cameras provided similar estimates of elk–fetus contact rates. Elk contacted fetuses and random control points equally, suggesting that elk were not attracted to fetuses but encountered them incidentally while feeding. The modeled relationship between contact rate and disease prevalence is nonlinear and LD feeding may result in large reductions in brucellosis prevalence, but this depends on the amount of transmission that occurs on and off feedgrounds.
A Robust, Microwave Rain Gauge
NASA Astrophysics Data System (ADS)
Mansheim, T. J.; Niemeier, J. J.; Kruger, A.
2008-12-01
Researchers at The University of Iowa have developed an all-electronic rain gauge that uses microwave sensors operating at either 10 GHz or 23 GHz, and measures the Doppler shift caused by falling raindrops. It is straightforward to interface these sensors with conventional data loggers, or integrate them into a wireless sensor network. A disadvantage of these microwave rain gauges is that they consume significant power when they are operating. However, this may be partially negated by using data loggers' or sensors networks' sleep-wake-sleep mechanism. Advantages of the microwave rain gauges are that one can make them very robust, they cannot clog, they don't have mechanical parts that wear out, and they don't have to be perfectly level. Prototype microwave rain gauges were collocated with tipping-bucket rain gauges, and data were collected for two seasons. At higher rain rates, microwave rain gauge measurements compare well with tipping-bucket measurements. At lower rain rates, the microwave rain gauges provide more detailed information than tipping buckets, which quantize measurement typically in 1 tip per 0.01 inch, or 1 tip per mm of rainfall.
Atmospheric corrosion of metals in industrial city environment.
Kusmierek, Elzbieta; Chrzescijanska, Ewa
2015-06-01
Atmospheric corrosion is a significant problem given destruction of various materials, especially metals. The corrosion investigation in the industrial city environment was carried out during one year exposure. Corrosion potential was determined using the potentiometric method. The highest effect of corrosion processes was observed during the winter season due to increased air pollution. Corrosion of samples pre-treated in tannic acid before the exposure was more difficult compared with the samples without pretreatment. The corrosion products determined with the SEM/EDS method prove that the most corrosive pollutants present in the industrial city air are SO2, CO2, chlorides and dust.
NASA Astrophysics Data System (ADS)
Lu, J. Z.; Han, B.; Cui, C. Y.; Li, C. J.; Luo, K. Y.
2017-02-01
The effects of massive laser shock peening (LSP) treatment with different coverage layers on residual stress, pitting morphologies in a standard corrosive solution and electrochemical corrosion resistance of AISI 4145 steel were investigated by pitting corrosion test, potentiodynamic polarisation test, and SEM observations. Results showed massive LSP treatment can effectively cause an obvious improvement of pitting corrosion resistance of AISI 4145 steel, and increased coverage layer can also gradually improve its corrosion resistance. Massive LSP treatment with multiple layers was shown to influence pitting corrosion behaviour in a standard corrosive solution.
Corrosion-Activated Micro-Containers for Environmentally Friendly Corrosion Protective Coatings
NASA Technical Reports Server (NTRS)
Li, Wenyan; Buhrow, J. W.; Zhang, X.; Johnsey, M. N.; Pearman, B. P.; Jolley, S. T.; Calle, L. M.
2016-01-01
This work concerns the development of environmentally friendly encapsulation technology, specifically designed to incorporate corrosion indicators, inhibitors, and self-healing agents into a coating, in such a way that the delivery of the indicators and inhibitors is triggered by the corrosion process, and the delivery of self-healing agents is triggered by mechanical damage to the coating. Encapsulation of the active corrosion control ingredients allows the incorporation of desired autonomous corrosion control functions such as: early corrosion detection, hidden corrosion detection, corrosion inhibition, and self-healing of mechanical damage into a coating. The technology offers the versatility needed to include one or several corrosion control functions into the same coating.The development of the encapsulation technology has progressed from the initial proof-of-concept work, in which a corrosion indicator was encapsulated into an oil-core (hydrophobic) microcapsule and shown to be delivered autonomously, under simulated corrosion conditions, to a sophisticated portfolio of micro carriers (organic, inorganic, and hybrid) that can be used to deliver a wide range of active corrosion ingredients at a rate that can be adjusted to offer immediate as well as long-term corrosion control. The micro carriers have been incorporated into different coating formulas to test and optimize the autonomous corrosion detection, inhibition, and self-healing functions of the coatings. This paper provides an overview of progress made to date and highlights recent technical developments, such as improved corrosion detection sensitivity, inhibitor test results in various types of coatings, and highly effective self-healing coatings based on green chemistry. The NASA Kennedy Space Centers Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion indicators, inhibitors and self-healing agents. This allows the incorporation of autonomous corrosion control functionalities, such as corrosion detection and inhibition as well as the self-healing of mechanical damage, into coatings. This paper presents technical details on the characterization of inhibitor-containing particles and their corrosion inhibitive effects using electrochemical and mass loss methods.Three organic environmentally friendly corrosion inhibitors were encapsulated in organic microparticles that are compatible with desired coatings. The release of the inhibitors from the microparticles in basic solution was studied. Fast release, for immediate corrosion protection, as well as long-term release for continued protection, was observed.The inhibition efficacy of the inhibitors, incorporated directly and in microparticles, on carbon steel was evaluated. Polarization curves and mass loss measurements showed that, in the case of 2MBT, its corrosion inhibition effectiveness was greater when it was delivered from microparticles.
Corrosion engineering in the utilization of the Raft River geothermal resource
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, R.L.
1976-08-01
The economic impact of corrosion and the particular problems of corrosion in the utilization of geothermal energy resources are noted. Corrosion is defined and the parameters that control corrosion in geothermal systems are discussed. A general background of corrosion is presented in the context of the various forms of corrosion, in relation to the Raft River geothermal system. A basic reference for mechanical design engineers involved in the design of geothermal energy recovery systems is provided.
Flow-induced corrosion behavior of absorbable magnesium-based stents.
Wang, Juan; Giridharan, Venkataraman; Shanov, Vesselin; Xu, Zhigang; Collins, Boyce; White, Leon; Jang, Yongseok; Sankar, Jagannathan; Huang, Nan; Yun, Yeoheung
2014-12-01
The aim of this work was to study corrosion behavior of magnesium (Mg) alloys (MgZnCa plates and AZ31 stents) under varied fluid flow conditions representative of the vascular environment. Experiments revealed that fluid hydrodynamics, fluid flow velocity and shear stress play essential roles in the corrosion behavior of absorbable magnesium-based stent devices. Flow-induced shear stress (FISS) accelerates the overall corrosion (including localized, uniform, pitting and erosion corrosions) due to the increased mass transfer and mechanical force. FISS increased the average uniform corrosion rate, the localized corrosion coverage ratios and depths and the removal rate of corrosion products inside the corrosion pits. For MgZnCa plates, an increase of FISS results in an increased pitting factor but saturates at an FISS of ∼0.15Pa. For AZ31 stents, the volume loss ratio (31%) at 0.056Pa was nearly twice that (17%) at 0Pa before and after corrosion. Flow direction has a significant impact on corrosion behavior as more severe pitting and erosion corrosion was observed on the back ends of the MgZnCa plates, and the corrosion product layer facing the flow direction peeled off from the AZ31 stent struts. This study demonstrates that flow-induced corrosion needs be understood so that Mg-based stents in vascular environments can be effectively designed. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Internal Corrosion and Deposition Control
This chapter reviews the current knowledge of the science of corrosion control and control of scaling in drinking water systems. Topics covered include: types of corrosion; physical, microbial and chemical factors influencing corrosion; corrosion of specific materials; direct ...
Corrosion resistance of steel materials in LiCl-KCl melts
NASA Astrophysics Data System (ADS)
Wang, Le; Li, Bing; Shen, Miao; Li, Shi-yan; Yu, Jian-guo
2012-10-01
The corrosion behaviors of 304SS, 316LSS, and Q235A in LiCl-KCl melts were investigated at 450°C by Tafel curves and electrochemical impedance spectroscopy (EIS). 316LSS shows the best corrosion resistance behaviors among the three materials, including the most positive corrosion potential and the smallest corrosion current from the Tafel curves and the largest electron transfer resistance from the Nyquist plots. The results are in good agreement with the weight losses in the static corrosion experiments for 45 h. This may be attributed to the better corrosion resistance of Mo and Ni existing as alloy elements in 316LSS, which exhibit the lower corrosion current densities and more positive corrosion potentials than 316LSS in the same melts.
Corrosion Performance of Inconel 625 in High Sulphate Content
NASA Astrophysics Data System (ADS)
Ismail, Azzura
2016-05-01
Inconel 625 (UNS N06625) is a type of nickel-chromium-molybdenum alloy with excellent corrosion resistance in a wide range of corrosive media, being especially resistant to pitting and crevice corrosion. However, in aggressive environment, Inconel 625 will suffer corrosion attack like other metals. This research compared the corrosion performance of Inconel 625 when exposed to higher sulphate content compared to real seawater. The results reveal that Inconel 625 is excellent in resist the corrosion attack in seawater. However, at increasing temperature, the corrosion resistance of this metal decrease. The performance is same in seawater with high sulphate content at increasing temperature. It can be concluded that sulphate promote perforation on Inconel 625 and become aggressive agents that accelerate the corrosion attack.
Microencapsulation of Corrosion Indicators for Smart Coatings
NASA Technical Reports Server (NTRS)
Li, Wenyan; Buhrow, Jerry W.; Jolley, Scott T.; Calle, Luz M.; Hanna,Joshua S.; Rawlins, James W.
2011-01-01
A multifunctional smart coating for the autonomous detection, indication, and control of corrosion is been developed based on microencapsulation technology. This paper summarizes the development, optimization, and testing of microcapsules specifically designed for early detection and indication of corrosion when incorporated into a smart coating. Results from experiments designed to test the ability of the microcapsules to detect and indicate corrosion, when blended into several paint systems, show that these experimental coatings generate a color change, indicative of spot specific corrosion events, that can be observed with the naked eye within hours rather than the hundreds of hours or months typical of the standard accelerated corrosion test protocols.. Key words: smart coating, corrosion detection, microencapsulation, microcapsule, pH-sensitive microcapsule, corrosion indicator, corrosion sensing paint
Barringer, J.L.; Kish, G.R.; Velnich, A.J.
1993-01-01
Ground water from the unconfined part of the Kirkwood-Cohansey aquifer system in the New Jersey Coastal Plain typically is corrosive-- that is, it is acidic, soft, and has low concentrations of alkalinity. Corrosive ground water has the potential to leach trace elements and asbestos fibers from plumbing materials used in potable- water systems, thereby causing potentially harmful concentrations of these substances in drinking water. Corrosion indices were calculated from water-quality data for 370 wells in the unconfined Kirkwood-Cohansey aquifer system. Values of the Langelier Saturation Index are predominantly negative, indicating that the water is undersaturated with respect to calcium carbonate, and, therefore, is potentially corrosive. Values of the Aggressive Index, a similar estimator of the corrosiveness of water, range from 3.9 (highly corrosive) to 11.9 (moderately corrosive). The median Aggressive Index value calculated for the 370 wells is 6.0, a value that indicates that the water is highly corrosive. Moderately corrosive ground water is found in some coastal areas. Isolated instances of moderately corrosive water are found in northern Ocean County, and in Burlington, Camden, and Salem Counties. In the vicinity of Ocean County corrosion-index values change little with depth, but in Atlantic, Burlington, and Salem Counties the corrosiveness of ground water generally appears to decrease with depth. Analyses of standing tap water from newly constructed homes in the Coastal Plain show concentrations of lead and other trace elements are significantly higher than those in ambient ground water. The elevated trace-element concentrations are attributed to the corrosion of plumbing materials by ground water. Results of the tap-water analyses substantiate the corrosiveness of Kirkwood-Cohansey ground water, as estimated by corrosion-index values.
NASA Astrophysics Data System (ADS)
Stockdale, Andrew
The use of low NOx boilers in coal fired power plants has resulted in sulfidizing corrosive conditions within the boilers and a reduction in the service lifetime of the waterwall tubes. As a solution to this problem, Ni-based weld overlays are used to provide the necessary corrosion resistance however; they are susceptible to corrosion fatigue. There are several metallurgical factors which give rise to corrosion fatigue that are associated with the localized melting and solidification of the weld overlay process. Coextruded coatings offer the potential for improved corrosion fatigue resistance since coextrusion is a solid state coating process. The corrosion and corrosion fatigue behavior of alloy 622 weld overlays and coextruded claddings was investigated using a Gleeble thermo-mechanical simulator retrofitted with a retort. The experiments were conducted at a constant temperature of 600°C using a simulated combustion gas of N2-10%CO-5%CO2-0.12%H 2S. An alternating stress profile was used with a minimum tensile stress of 0 MPa and a maximum tensile stress of 300 MPa (ten minute fatigue cycles). The results have demonstrated that the Gleeble can be used to successfully simulate the known corrosion fatigue cracking mechanism of Ni-based weld overlays in service. Multilayer corrosion scales developed on each of the claddings that consisted of inner and outer corrosion layers. The scales formed by the outward diffusion of cations and the inward diffusion of sulfur and oxygen anions. The corrosion fatigue behavior was influenced by the surface finish and the crack interactions. The initiation of a large number of corrosion fatigue cracks was not necessarily detrimental to the corrosion fatigue resistance. Finally, the as-received coextruded cladding exhibited the best corrosion fatigue resistance.
Simulation of Corrosion Process for Structure with the Cellular Automata Method
NASA Astrophysics Data System (ADS)
Chen, M. C.; Wen, Q. Q.
2017-06-01
In this paper, from the mesoscopic point of view, under the assumption of metal corrosion damage evolution being a diffusive process, the cellular automata (CA) method was proposed to simulate numerically the uniform corrosion damage evolution of outer steel tube of concrete filled steel tubular columns subjected to corrosive environment, and the effects of corrosive agent concentration, dissolution probability and elapsed etching time on the corrosion damage evolution were also investigated. It was shown that corrosion damage increases nonlinearly with increasing elapsed etching time, and the longer the etching time, the more serious the corrosion damage; different concentration of corrosive agents had different impacts on the corrosion damage degree of the outer steel tube, but the difference between the impacts was very small; the heavier the concentration, the more serious the influence. The greater the dissolution probability, the more serious the corrosion damage of the outer steel tube, but with the increase of dissolution probability, the difference between its impacts on the corrosion damage became smaller and smaller. To validate present method, corrosion damage measurements for concrete filled square steel tubular columns (CFSSTCs) sealed at both their ends and immersed fully in a simulating acid rain solution were conducted, and Faraday’s law was used to predict their theoretical values. Meanwhile, the proposed CA mode was applied for the simulation of corrosion damage evolution of the CFSSTCs. It was shown by the comparisons of results from the three methods aforementioned that they were in good agreement, implying that the proposed method used for the simulation of corrosion damage evolution of concrete filled steel tubular columns is feasible and effective. It will open a new approach to study and evaluate further the corrosion damage, loading capacity and lifetime prediction of concrete filled steel tubular structures.
A Multifunctional Coating for Autonomous Corrosion Control
NASA Technical Reports Server (NTRS)
Calle, L. M.; Hintze, P. E.; Li, W.; Buhrow, J. W.; Jolley, S. T.
2011-01-01
This slide presentation reviews the effects of corrosion on various structures at the Kennedy Space Center, and the work to discover a corrosion control coating that will be autonomous and will indicate corrosion at an early point in the process. Kennedy Space Center has many environmental conditions that are corrosive: ocean salt spray, heat, humidity, sunlight and acidic exhaust from the Solid Rocket Boosters (SRBs). Presented is a chart which shows the corrosion rates of carbon steel at various locations. KSC has the highest corrosion rates with 42.0 mils/yr, leading the next highest Galeta Point Beach, in the Panama Canal Zone with 27 mils/yr corrosion. A chart shows the changes in corrosion rate with the distance from the ocean. The three types of corrosion protective coatings are described: barrier (passive), Barrier plus active corrosion inhibiting components, and smart. A smart coating will detect and respond actively to changes in its environment in a functional and predictable manner and is capable of adapting its properties dynamically. The smart coating uses microcapsules, particles or liquid drops coated in polymers, that can detect and control the corrosion caused by the environment. The mechanism for a pH sensitive microcapsule and the hydrophobic core microcapsule are demonstrated and the chemistry is reviewed. When corrosion begins, the microcapsule will release the contents of the core (indicator, inhibitor, and self healing agent) in close proximity to the corrosion. The response to a pH increase is demonstrated by a series of pictures that show the breakdown of the microcapsule and the contents release. An example of bolt corrosion is used, as an example of corrosion in places that are difficult to ascertain. A comparison of various coating systems is shown.
An electrochemical study of the corrosion behavior of primer coated 2219-T87 aluminum
NASA Technical Reports Server (NTRS)
Danford, M. D.; Higgins, R. H.
1985-01-01
The corrosion behavior for 2219-T87 aluminum coated with various primers, including those used for the external tank and solid rocket boosters of the Space Shuttle Transportation System, were investigated using electrochemical techniques. Corrosion potential time, polarization resistance time, electrical resistance time, and corrosion rate time measurements were all investigated. It was found that electrical resistance time and corrosion rate time measurement were most useful for studying the corrosion behavior of painted aluminum. Electrical resistance time determination give useful information concerning the porosity of paint films, while corrosion rate time curves give important information concerning overall corrosion rates and corrosion mechanisms. In general, the corrosion rate time curves all exhibited at least one peak during the 30 day test period, which was attributed, according to the proposed mechanisms, to the onset of the hydrogen evolution reaction and the beginning of destruction of the protective properties of the paint film.
NASA Astrophysics Data System (ADS)
Wang, Yan; Huang, Zhiquan; Yan, Qin; Liu, Chen; Liu, Peng; Zhang, Yi; Guo, Changhong; Jiang, Guirong; Shen, Dejiu
2016-08-01
The effects of corrosion products on corrosion behaviors of AZ31 magnesium alloy with a plasma electrolytic oxidation (PEO) coating were investigated under the salt spray corrosion test (SSCT). The surface morphology, cross-sectional microstructure, chemical and phase compositions of the PEO coating were determined using scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction analysis (XRD), respectively. Further, the corrosion process of the samples under the SSCT was examined in a non-aqueous electrolyte (methanol) using electrochemical impedance spectroscopy (EIS) coupled with equivalent circuit. The results show that the inner layer of the coating was destroyed firstly and the corrosion products have significant effects on the corrosion behaviors of the coating. The results above are discussed and an electrochemical corrosion model is proposed in the paper.
Recent Developments on Autonomous Corrosion Protection Through Encapsulation
NASA Technical Reports Server (NTRS)
Li, W.; Buhrow, J. W.; Calle, L. M.; Gillis, M.; Blanton, M.; Hanna, J.; Rawlins, J.
2015-01-01
This paper concerns recent progress in the development of a multifunctional smart coating, based on microencapsulation, for the autonomous detection and control of corrosion. Microencapsulation has been validated and optimized to incorporate desired corrosion control functionalities, such as early corrosion detection and inhibition, through corrosion-initiated release of corrosion indicators and inhibitors, as well as self-healing agent release triggered by mechanical damage. While proof-of-concept results have been previously reported, more recent research and development efforts have concentrated on improving coating compatibility and synthesis procedure scalability, with a targeted goal of obtaining easily dispersible pigment-grade type microencapsulated materials. The recent progress has resulted in the development of pH-sensitive microparticles as a corrosion-triggered delivery system for corrosion indicators and inhibitors. The synthesis and early corrosion indication results obtained with coating formulations that incorporate these microparticles are reported. The early corrosion indicating results were obtained with color changing and with fluorescent indicators.
NASA Technical Reports Server (NTRS)
Parker, R. J.; Bamberger, E. N.; Nahm, A. H.
1983-01-01
Corrosion tests were run with AISI 52100, AISI M-50 and AMS 5794 under conditions that simulate the crevice corrosion found in aircraft ball and roller bearings rejected at overhaul for corrosion. Test specimens were fabricated that simulated the contacts of balls or rollers and the raceways. Corrosion cells were assembled in the presence of a lubricant contaminated with water and chloride ions. The cell was then thermally cycled between 339 K (150 F) and 276 K (37 F). The corrosion observed after 14 cycles was that of crevice and pitting corrosion typically found in aircraft bearings. AMS 5749 showed a very slight amount of corrosion. No appreciable differences were noted between AISI 52100 and AISI M-50, but both showed much greater corrosion than AMS 5749. The corrosion pits observed in AISI M-50 appeared to be fewer in number but generally deeper and larger than in AISI 52100.
Ultrasonic Corrosion Fatigue Behavior of High Strength Austenitic Stainless Steels
NASA Astrophysics Data System (ADS)
Ebara, R.; Yamaguchi, Y.; Kanei, D.; Yamamoto, Y.
Ultrasonic corrosion fatigue tests were conducted for high strength austenitic stainless steels such as YUS270 and SUS304N2 in 3%NaCl aqueous solution. The reduction of giga-cycle corrosion fatigue strength of YUS270 and SUS304N2 was not observed at all, while the reduction of corrosion fatigue life was observed at higher stress amplitude. Corrosion pit was observed on corrosion fatigue crack initiation area. Striation was predominantly observed on crack propagation area in air and in 3% NaCl aqueous solution. The reduction of corrosion fatigue strength of high strength austenitic stainless steels such as YUS270 and SUS304N2 is due to the corrosion pit formation at corrosion fatigue crack initiation area. It can be concluded that the higher the ultimate tensile strength of austenitic stainless steels the higher the giga-cycle corrosion fatigue strength in 3%NaCl aqueous solution is.
NASA Technical Reports Server (NTRS)
Rawdon, Henry S
1928-01-01
The permanence, with respect to corrosion, of light aluminum alloy sheets of the duralumin type, that is, heat-treatable alloys containing Cu, Mg, Mn, and Si is discussed. Alloys of this type are subject to surface corrosion and corrosion of the interior by intercrystalline paths. Results are given of accelerated corrosion tests, tensile tests, the effect on corrosion of various alloying elements and heat treatments, electrical resistance measurements, and X-ray examinations.
Corrosion of High-Density Sintered Tungsten Alloys. Part 2. Accelerated Corrosion Testing
1988-12-01
REPORT MRL-R- 1145 CORROSION OF HIGH-DENSITY SINTERED TUNGSTEN ALLOYS PART 2: ACCELERATED CORROSION TESTING J.J. Batten and B.T. Moore I DTIC . *arit*fl...Commo,,wea°h 91 Avor,++.°_ DECEMBER 1988 012 rI DEPARTMENT OF DEFENCE MATERIALS RESEARCH LABORATORY REPORT MRL-R- 1145 CORROSION OF HIGH-DENSITY SINTERED...TUNGSTEN ALLOYS PART 2: ACCELERATED CORROSION TESTING J.J. Batten and B.T. Moore ABSTRACT As a consequence of corrosion during long-term storage in
Controlling stress corrosion cracking in mechanism components of ground support equipment
NASA Technical Reports Server (NTRS)
Majid, W. A.
1988-01-01
The selection of materials for mechanism components used in ground support equipment so that failures resulting from stress corrosion cracking will be prevented is described. A general criteria to be used in designing for resistance to stress corrosion cracking is also provided. Stress corrosion can be defined as combined action of sustained tensile stress and corrosion to cause premature failure of materials. Various aluminum, steels, nickel, titanium and copper alloys, and tempers and corrosive environment are evaluated for stress corrosion cracking.
2009-01-01
Background Our understanding of the effects of human movement on dengue virus spread remains limited in part due to the lack of precise tools to monitor the time-dependent location of individuals. We determined the utility of a new, commercially available, GPS data-logger for long-term tracking of human movements in Iquitos, Peru. We conducted a series of evaluations focused on GPS device attributes key to reliable use and accuracy. GPS observations from two participants were later compared with semi-structured interview data to assess the usefulness of GPS technology to track individual mobility patterns. Results Positional point and line accuracy were 4.4 and 10.3 m, respectively. GPS wearing mode increased spatial point error by 6.9 m. Units were worn on a neck-strap by a carpenter and a moto-taxi driver for 14-16 days. The application of a clustering algorithm (I-cluster) to the raw GPS positional data allowed the identification of locations visited by each participant together with the frequency and duration of each visit. The carpenter moved less and spent more time in more fixed locations than the moto-taxi driver, who visited more locations for a shorter period of time. GPS and participants' interviews concordantly identified 6 common locations, whereas GPS alone identified 4 locations and participants alone identified 10 locations. Most (80%) of the locations identified by participants alone were places reported as visited for less than 30 minutes. Conclusion The present study demonstrates the feasibility of a novel, commercially available GPS data-logger for long-term tracking of humans and shows the potential of these units to quantify mobility patterns in relationship with dengue virus transmission risk in a tropical urban environment. Cost, battery life, size, programmability and ease of wear are unprecedented from previously tested units, proving the usefulness of GPS-dataloggers for linking movement of individuals and transmission risk of dengue virus and other infectious agents, particularly in resource-poor settings. PMID:19948034
A ocean bottom vector magnetometer
NASA Astrophysics Data System (ADS)
Wang, Xiaomei; Teng, Yuntian; Wang, Chen; Ma, Jiemei
2017-04-01
The new development instrument with a compact spherical coil system and Overhauser magnetometer for measuring the total strength of the magnetic field and the vectors of strength, Delta inclination - Delta declination, meanwhile we also use a triaxial fluxgate instrument of the traditional instrument for geomagnetic vector filed measurement. The advantages of this method are be calibrated by each other and get good performances with automatic operation, good stability and high resolution. Firstly, a brief description of the instrument measurement principles and the key technologies are given. The instrument used a spherical coil system with 34 coils to product the homogeneous volume inside the coils which is large enough to accommodate the sensor of Overhauser total field sensor; the rest of the footlocker-sized ocean-bottom vector magnetometer consists of equipment to run the sensors and records its data (batteries and a data logger), weight to sink it to the sea floor, a remote-controlled acoustic release and flotation to bring the instrument back to the surface. Finally, the accuracy of the instrument was tested in the Geomagnetic station, and the measurement accuracies of total strength and components were better than 0.2nT and 1nT respectively. The figure 1 shows the development instrument structure. it includes six thick glass spheres which protect the sensor, data logger and batteries from the pressures of the deep sea, meanwhile they also provide recycling positive buoyancy; To cushion the glass, the spheres then go inside yellow plastic "hardhats". The triaxial fluxgate is inside No.1 glass spheres, data logger and batteries are inside No.2 glass spheres, the new vector sensor is inside No.3 glass spheres, acoustic communication unit is inside No.4 glass spheres, No.5 and No.6 glass spheres are empty which only provide recycling positive buoyancy. The figure 2 shows the development instrument Physical photo.
High-Altitude Hydration System
NASA Technical Reports Server (NTRS)
Parazynski, Scott E.; Orndoff, Evelyne; Bue, Grant C.; Schaefbauer, Mark E.; Urban, Kase
2010-01-01
Three methods are being developed for keeping water from freezing during high-altitude climbs so that mountaineers can remain hydrated. Three strategies have been developed. At the time of this reporting two needed to be tested in the field and one was conceptual. The first method is Passive Thermal Control Using Aerogels. This involves mounting the fluid reservoir of the climber s canteen to an inner layer of clothing for better heat retention. For the field test, bottles were mounted to the inner fleece layer of clothing, and then aerogel insulation was placed on the outside of the bottle, and circumferentially around the drink straw. When climbers need to drink, they can pull up the insulated straw from underneath the down suit, take a sip, and then put it back into the relative warmth of the suit. For the field test, a data logger assessed the temperatures of the water reservoir, as well as near the tip of the drink straw. The second method is Passive Thermal Control with Copper-Shielded Drink Straw and Aerogels, also mounted to inner layers of clothing for better heat retention. Braided wire emanates from the inside of the fleece jacket layer, and continues up and around the drink straw in order to use body heat to keep the system-critical drink straw warm enough to keep water in the liquid state. For the field test, a data logger will be used to compare this with the above concept. The third, and still conceptual, method is Active Thermal Control with Microcontroller. If the above methods do not work, microcontrollers and tape heaters have been identified that could keep the drink straw warm even under extremely cold conditions. Power requirements are not yet determined because the thermal environment inside the down suit relative to the external environment has not been established. A data logger will be used to track both the external and internal temperatures of the suit on a summit day.
Flow Classification and Cave Discharge Characteristics in Unsaturated Karst Formation
NASA Astrophysics Data System (ADS)
Mariethoz, G.; Mahmud, K.; Baker, A.; Treble, P. C.
2015-12-01
In this study we utilize the spatial array of automated cave drip monitoring in two large chambers of the Golgotha Cave, SW Australia, developed in Quaternary aeolianite (dune limestone), with the aim of understanding infiltration water movement via the relationships between infiltration, stalactite morphology and groundwater recharge. Mahmud et al. (2015) used the Terrestrial LiDAR measurements to analyze stalactite morphology and to characterize possible flow locations in this cave. Here we identify the stalactites feeding the drip loggers and classify each as matrix (soda straw or icicle), fracture or combined-flow. These morphology-based classifications are compared with flow characteristics from the drip logger time series and the discharge from each stalactite is calculated. The total estimated discharge from each area is compared with infiltration estimates to better understand flow from the surface to the cave ceilings of the studied areas. The drip discharge data agrees with the morphology-based flow classification in terms of flow and geometrical characteristics of cave ceiling stalactites. No significant relationships were observed between the drip logger discharge, skewness and coefficient of variation with overburden thickness, due to the possibility of potential vadose-zone storage volume and increasing complexity of the karst architecture. However, these properties can be used to characterize different flow categories. A correlation matrix demonstrates that similar flow categories are positively correlated, implying significant influence of spatial distribution. The infiltration water comes from a larger surface area, suggesting that infiltration is being focused to the studied ceiling areas of each chamber. Most of the ceiling in the cave site is dry, suggesting the possibility of capillary effects with water moving around the cave rather than passing through it. Reference:Mahmud et al. (2015), Terrestrial Lidar Survey and Morphological Analysis to Identify Infiltration Properties in the Tamala Limestone, Western Australia, IEEE JSTARS, DOI: 10.1109/JSTARS.2015.2451088, in Press.
Vazquez-Prokopec, Gonzalo M; Stoddard, Steven T; Paz-Soldan, Valerie; Morrison, Amy C; Elder, John P; Kochel, Tadeusz J; Scott, Thomas W; Kitron, Uriel
2009-11-30
Our understanding of the effects of human movement on dengue virus spread remains limited in part due to the lack of precise tools to monitor the time-dependent location of individuals. We determined the utility of a new, commercially available, GPS data-logger for long-term tracking of human movements in Iquitos, Peru. We conducted a series of evaluations focused on GPS device attributes key to reliable use and accuracy. GPS observations from two participants were later compared with semi-structured interview data to assess the usefulness of GPS technology to track individual mobility patterns. Positional point and line accuracy were 4.4 and 10.3 m, respectively. GPS wearing mode increased spatial point error by 6.9 m. Units were worn on a neck-strap by a carpenter and a moto-taxi driver for 14-16 days. The application of a clustering algorithm (I-cluster) to the raw GPS positional data allowed the identification of locations visited by each participant together with the frequency and duration of each visit. The carpenter moved less and spent more time in more fixed locations than the moto-taxi driver, who visited more locations for a shorter period of time. GPS and participants' interviews concordantly identified 6 common locations, whereas GPS alone identified 4 locations and participants alone identified 10 locations. Most (80%) of the locations identified by participants alone were places reported as visited for less than 30 minutes. The present study demonstrates the feasibility of a novel, commercially available GPS data-logger for long-term tracking of humans and shows the potential of these units to quantify mobility patterns in relationship with dengue virus transmission risk in a tropical urban environment. Cost, battery life, size, programmability and ease of wear are unprecedented from previously tested units, proving the usefulness of GPS-dataloggers for linking movement of individuals and transmission risk of dengue virus and other infectious agents, particularly in resource-poor settings.
NASA Astrophysics Data System (ADS)
Hirahara, S.; Nakayama, T.; Hori, S.; Sato, T.; Chiba, Y.; Okada, T.; Matsuzawa, T.
2015-12-01
Soon after the 2011 Tohoku earthquake, seismic activity of Tohoku region, NE Japan is induced in the inland area of Akita prefecture and the border area between Fukushima and Yamagata prefectures. We plan to install a total of 80 offline seismic observation stations in these areas for studying the effect of megathrust earthquake on the activities of inland earthquakes. In our project, maintenance will be held twice-a-year for 4 years from 2015 by using 2.0Hz short-period 3-component seismometer, KVS-300 and ultra-low-power data logger, EDR-X7000 (DC12V 0.08W power supply). We installed seismometer on the rock surface or the slope of the natural ground at the possible sites confirmed with low noise level to obtain distinct seismic waveform data. We report an improvement in installation method of the offline seismic observation station in the heavy snowfall area of Tohoku region based on the retrieved data. In the conventional method, seismometer was installed in the hand-dug hole of a slope in case it is not waterproof. Data logger and battery were installed in the box container on the ground surface, and then, GPS antenna was installed on the pole fixed by stepladder. There are risks of the inclination of seismometer and the damage of equipment in heavy snowfall area. In the new method, seismometer is installed in the robust concrete box on the buried basement consists of precast concrete mass to keep its horizontality. Data logger, battery, and GPS antenna are installed on a high place by using a single pole with anchor bolt and a pole mount cabinet to enhance their safety. As a result, total costs of installation are kept down because most of the equipment is reusable. Furthermore, an environmental burden of waste products is reduced.
Towards a more practical attention bias test to assess affective state in sheep
Doyle, Rebecca E.; Colditz, Ian G.; Belson, Sue; Cronin, Greg M.; Lee, Caroline
2018-01-01
Tests for attention bias potentially offer more rapid assessment of affective state in animals than existing cognitive methods. An attention bias test has previously been developed for sheep and validated as a measure of anxious states. The 3 minute test assessed behavioural responses of sheep in an enclosed arena after brief exposure to the threat of a dog. Experiment 1 of the current study aimed to refine the previously developed method, removing the need for a habituation period and shortening the test duration. Sheep were given either an anxiolytic drug, an anxiogenic drug or a control treatment prior to testing to induce contrasting affective states. Differences in behaviour were found between the treatment groups within the first 45s of the test, indicating the original test duration could be shortened from 180 s. During testing, 36 of 40 animals in the control and anxiolytic groups ate the novel feed offered in the test, indicating it is not necessary to habituate animals to a feed container. Experiment 2 aimed to confirm the responses measured in the test were primarily towards the dog rather than other aspects of the test environment. Sheep exposed to an empty window at the beginning of the test behaved differently to those which were exposed to a dog, indicating sheep behaviour in the test is at least partially a response to the dog. A third group of sheep were also tested with the dog immediately after having small data loggers attached to their necks. Behaviour of these sheep did not differ from the sheep tested without loggers, indicating data logger attachment did not impact their behaviour in the test. In both experiments, treatments did not appear to modify activity (zones crossed), which we propose indicates the test was primarily detecting valence of the affective state rather than arousal. PMID:29293636
Scully, John R
2015-01-01
Recent advances in characterization tools, computational capabilities, and theories have created opportunities for advancement in understanding of solid-fluid interfaces at the nanoscale in corroding metallic systems. The Faraday Discussion on Corrosion Chemistry in 2015 highlighted some of the current needs, gaps and opportunities in corrosion science. Themes were organized into several hierarchical categories that provide an organizational framework for corrosion. Opportunities to develop fundamental physical and chemical data which will enable further progress in thermodynamic and kinetic modelling of corrosion were discussed. These will enable new and better understanding of unit processes that govern corrosion at the nanoscale. Additional topics discussed included scales, films and oxides, fluid-surface and molecular-surface interactions, selected topics in corrosion science and engineering as well as corrosion control. Corrosion science and engineering topics included complex alloy dissolution, local corrosion, and modelling of specific corrosion processes that are made up of collections of temporally and spatially varying unit processes such as oxidation, ion transport, and competitive adsorption. Corrosion control and mitigation topics covered some new insights on coatings and inhibitors. Further advances in operando or in situ experimental characterization strategies at the nanoscale combined with computational modelling will enhance progress in the field, especially if coupling across length and time scales can be achieved incorporating the various phenomena encountered in corrosion. Readers are encouraged to not only to use this ad hoc organizational scheme to guide their immersion into the current opportunities in corrosion chemistry, but also to find value in the information presented in their own ways.
Combining hygrothermal and corrosion models to predict corrosion of metal fasteners embedded in wood
Samuel L. Zelinka; Dominique Derome; Samuel V. Glass
2011-01-01
A combined heat, moisture, and corrosion model is presented and used to simulate the corrosion of metal fasteners embedded in solid wood exposed to the exterior environment. First, the moisture content and temperature at the wood/fastener interface is determined at each time step. Then, the amount of corrosion is determined spatially using an empirical corrosion rate...
An Investigation of Anaerobic Processes in Fuel/Natural Seawater Environments
2012-02-08
Corrosion rates were estimated from polarization resistance measurements and corrosion was measured by weight loss. Corrosion attack morphology and...rates were estimated from polarization resistance measurements and corrosion was measured by weight loss. Corrosion attack morphology and corrosion...the backside of the coupons with conductive epoxy and carbon tape to achieve electrical connection. Coupons were individually mounted in epoxy to
Atmospheric corrosion of metals in industrial city environment
Kusmierek, Elzbieta; Chrzescijanska, Ewa
2015-01-01
Atmospheric corrosion is a significant problem given destruction of various materials, especially metals. The corrosion investigation in the industrial city environment was carried out during one year exposure. Corrosion potential was determined using the potentiometric method. The highest effect of corrosion processes was observed during the winter season due to increased air pollution. Corrosion of samples pre-treated in tannic acid before the exposure was more difficult compared with the samples without pretreatment. The corrosion products determined with the SEM/EDS method prove that the most corrosive pollutants present in the industrial city air are SO2, CO2, chlorides and dust. PMID:26217736
NASA Astrophysics Data System (ADS)
Li, Shiwei; Gao, Bo; Yin, Shaohua; Tu, Ganfeng; Zhu, Guanglin; Sun, Shuchen; Zhu, Xiaoping
2015-12-01
The effects of Si and RE on the microstructure and corrosion resistance of Zn-6Al-3Mg coating (ZAM) have been investigated. Surface morphology observations of the coating and corrosion products reveal that the additions of Si and rare earth metals (RES) improve the microstructural homogeneity of ZAMSR coating and stability of corrosion products formed on ZAMSR coating. Moreover, only uniform corrosion occurs in ZAMSR coating during the corrosion test, while intergranular corrosion and pitting occur in ZAM. As a result, the corrosion resistance of ZAM coating is improved by the additions of Si and RES.
Corrosion Behavior of Weathering Steel Under Thin Electrolyte Layer at Different Relative Humidity
NASA Astrophysics Data System (ADS)
Xia, Yan; Liu, Pan; Zhang, Jianqing; Cao, Fahe
2018-01-01
The corrosion behavior of weathering steel under thin electrolyte layer (TEL) at different relative humidity (RH) was investigated by cathodic polarization, electrochemical impedance spectroscopy, electrochemical noise, SEM/EDS, XRD and Raman spectroscopy. The results indicate that during the initial stage, the corrosion rate increases as the RH decreases when the initial thickness of TEL is above 100 μm. During the middle and final corrosion stages, the corrosion behavior of weathering steel is influenced by RH, the initial thickness of TEL and corrosion product. The TEL corrosion is divided into three types, and a weathering steel corrosion model under TEL and bulk solution is also proposed.
Xu, Yunze; Li, Kaiqiang; Liu, Liang; Yang, Lujia; Wang, Xiaona; Huang, Yi
2016-01-01
In this paper, a new kind of carbon steel (CS) and stainless steel (SS) galvanic sensor system was developed for the study of rebar corrosion in different pore solution conditions. Through the special design of the CS and SS electronic coupons, the electronic resistance (ER) method and zero resistance ammeter (ZRA) technique were used simultaneously for the measurement of both the galvanic current and the corrosion depth. The corrosion processes in different solution conditions were also studied by linear polarization resistance (LPR) and the measurements of polarization curves. The test result shows that the galvanic current noise can provide detailed information of the corrosion processes. When localized corrosion occurs, the corrosion rate measured by the ER method is lower than the real corrosion rate. However, the value measured by the LPR method is higher than the real corrosion rate. The galvanic current and the corrosion current measured by the LPR method shows linear correlation in chloride-containing saturated Ca(OH)2 solution. The relationship between the corrosion current differences measured by the CS electronic coupons and the galvanic current between the CS and SS electronic coupons can also be used to evaluate the localized corrosion in reinforced concrete. PMID:27618054
Xu, Yunze; Li, Kaiqiang; Liu, Liang; Yang, Lujia; Wang, Xiaona; Huang, Yi
2016-09-08
In this paper, a new kind of carbon steel (CS) and stainless steel (SS) galvanic sensor system was developed for the study of rebar corrosion in different pore solution conditions. Through the special design of the CS and SS electronic coupons, the electronic resistance (ER) method and zero resistance ammeter (ZRA) technique were used simultaneously for the measurement of both the galvanic current and the corrosion depth. The corrosion processes in different solution conditions were also studied by linear polarization resistance (LPR) and the measurements of polarization curves. The test result shows that the galvanic current noise can provide detailed information of the corrosion processes. When localized corrosion occurs, the corrosion rate measured by the ER method is lower than the real corrosion rate. However, the value measured by the LPR method is higher than the real corrosion rate. The galvanic current and the corrosion current measured by the LPR method shows linear correlation in chloride-containing saturated Ca(OH)₂ solution. The relationship between the corrosion current differences measured by the CS electronic coupons and the galvanic current between the CS and SS electronic coupons can also be used to evaluate the localized corrosion in reinforced concrete.
The dual role of microbes in corrosion
Kip, Nardy; van Veen, Johannes A
2015-01-01
Corrosion is the result of a series of chemical, physical and (micro) biological processes leading to the deterioration of materials such as steel and stone. It is a world-wide problem with great societal and economic consequences. Current corrosion control strategies based on chemically produced products are under increasing pressure of stringent environmental regulations. Furthermore, they are rather inefficient. Therefore, there is an urgent need for environmentally friendly and sustainable corrosion control strategies. The mechanisms of microbially influenced corrosion and microbially influenced corrosion inhibition are not completely understood, because they cannot be linked to a single biochemical reaction or specific microbial species or groups. Corrosion is influenced by the complex processes of different microorganisms performing different electrochemical reactions and secreting proteins and metabolites that can have secondary effects. Information on the identity and role of microbial communities that are related to corrosion and corrosion inhibition in different materials and in different environments is scarce. As some microorganisms are able to both cause and inhibit corrosion, we pay particular interest to their potential role as corrosion-controlling agents. We show interesting interfaces in which scientists from different disciplines such as microbiology, engineering and art conservation can collaborate to find solutions to the problems caused by corrosion. PMID:25259571
The dual role of microbes in corrosion.
Kip, Nardy; van Veen, Johannes A
2015-03-01
Corrosion is the result of a series of chemical, physical and (micro) biological processes leading to the deterioration of materials such as steel and stone. It is a world-wide problem with great societal and economic consequences. Current corrosion control strategies based on chemically produced products are under increasing pressure of stringent environmental regulations. Furthermore, they are rather inefficient. Therefore, there is an urgent need for environmentally friendly and sustainable corrosion control strategies. The mechanisms of microbially influenced corrosion and microbially influenced corrosion inhibition are not completely understood, because they cannot be linked to a single biochemical reaction or specific microbial species or groups. Corrosion is influenced by the complex processes of different microorganisms performing different electrochemical reactions and secreting proteins and metabolites that can have secondary effects. Information on the identity and role of microbial communities that are related to corrosion and corrosion inhibition in different materials and in different environments is scarce. As some microorganisms are able to both cause and inhibit corrosion, we pay particular interest to their potential role as corrosion-controlling agents. We show interesting interfaces in which scientists from different disciplines such as microbiology, engineering and art conservation can collaborate to find solutions to the problems caused by corrosion.
PH and Electrochemical Responsive Materials for Corrosion Smart Coating Applications
NASA Technical Reports Server (NTRS)
Li, Wenyan; Calle, Luz M.
2008-01-01
Corrosion is a costly issue for military operations and civil industries. While most corrosion initiates from localized corrosion form, such as pitting, failure directly caused by localized corrosion is the most dangerous kind, because it is difficult to anticipate and prevent, occurs very suddenly and can be catastrophic. One way of preventing these failures is with a coating that can detect and heal localized corrosion. pH and other electrochemical changes are often associated with localized corrosion, so it is expected that materials that are pH or otherwise electrochemical responsive can be used to detect and control corrosion. This paper will review various pH and electrochemical responsive materials and their potential applications in corrosion smart coatings. Current research results in this field will also be reported.
Corrosion-resistant high-entropy alloys: A review
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, Yunzhu; Yang, Bin; Liaw, Peter
Corrosion destroys more than three percent of the world’s gross domestic product. Therefore, the design of highly corrosion-resistant materials is urgently needed. By breaking the classical alloy-design philosophy, high-entropy alloys (HEAs) possess unique microstructures, which are solid solutions with random arrangements of multiple elements. The particular locally-disordered chemical environment is expected to lead to unique corrosion-resistant properties. In this review, the studies of the corrosion-resistant HEAs during the last decade are summarized. The corrosion-resistant properties of HEAs in various aqueous environments and the corrosion behavior of HEA coatings are presented. The effects of environments, alloying elements, and processing methods onmore » the corrosion resistance are analyzed in detail. Finally, the possible directions of future work regarding the corrosion behavior of HEAs are suggested.« less
Corrosion-resistant high-entropy alloys: A review
Shi, Yunzhu; Yang, Bin; Liaw, Peter
2017-02-05
Corrosion destroys more than three percent of the world’s gross domestic product. Therefore, the design of highly corrosion-resistant materials is urgently needed. By breaking the classical alloy-design philosophy, high-entropy alloys (HEAs) possess unique microstructures, which are solid solutions with random arrangements of multiple elements. The particular locally-disordered chemical environment is expected to lead to unique corrosion-resistant properties. In this review, the studies of the corrosion-resistant HEAs during the last decade are summarized. The corrosion-resistant properties of HEAs in various aqueous environments and the corrosion behavior of HEA coatings are presented. The effects of environments, alloying elements, and processing methods onmore » the corrosion resistance are analyzed in detail. Finally, the possible directions of future work regarding the corrosion behavior of HEAs are suggested.« less
Evaluation of Encapsulated Inhibitor for Autonomous Corrosion Protection
NASA Technical Reports Server (NTRS)
Johnsey, M. N.; Li, W.; Buhrow, J. W.; Calle, L. M.; Pearman, B. P.; Zhang, X.
2015-01-01
This work concerns the development of smart coating technologies based on microencapsulation for the autonomous control of corrosion. Microencapsulation allows the incorporation of corrosion inhibitors into coating which provides protection through corrosion-controlled release of these inhibitors.One critical aspect of a corrosion protective smart coating is the selection of corrosion inhibitor for encapsulation and comparison of the inhibitor function before and after encapsulation. For this purpose, a systematic approach is being used to evaluate free and encapsulated corrosion inhibitors by salt immersion. Visual, optical microscope, and Scanning Electron Microscope (with low-angle backscatter electron detector) are used to evaluate these inhibitors. It has been found that the combination of different characterization tools provide an effective method for evaluation of early stage localized corrosion and the effectiveness of corrosion inhibitors.
Effect of mechanical treatment on intergranular corrosion of 6064 alloy bars
NASA Astrophysics Data System (ADS)
Sláma, P.; Nacházel, J.
2017-02-01
Aluminium Al-Mg-Si-type alloys (6xxx-series) exhibit good mechanical properties, formability, weldability and good corrosion resistance in various environments. They often find use in automotive industry and other applications. Some alloys, however, particularly those with higher copper levels, show increased susceptibility to intergranular corrosion. Intergranular corrosion (IGC) is typically related to the formation of microgalvanic cells between cathodic, more noble phases and depleted (precipitate-free) zones along grain boundaries. It is encountered mainly in AlMgSi alloys containing Cu, where it is thought to be related to the formation Q-phase precipitates (Al4Mg8Si7Cu2) along grain boundaries. The present paper describes the effects of mechanical working (extrusion, drawing and straightening) and artificial aging on intergranular corrosion in rods of the 6064 alloy. The resistance to intergranular corrosion was mapped using corrosion tests according to EN ISO 11846, method B. Corrosion tests showed dependence of corrosion type on mechanical processing of the material. Intergranular, pitting and transgranular corrosion was observed. Artificial ageing influenced mainly the depth of the corrosion.
NASA Technical Reports Server (NTRS)
Mendreck, M. J.; Hurless, B. E.; Torres, P. D.; Danford, M. D.
1998-01-01
The corrosion and stress corrosion cracking (SCC) characteristics of annealed and hardened 440C stainless steel were evaluated in high humidity and 3.5-percent NaCl solution. Corrosion testing consisted of an evaluation of flat plates, with and without grease, in high humidity, as well as electrochemical testing in 3.5-percent NaCl. Stress corrosion testing consisted of conventional, constant strain, smooth bar testing in high humidity in addition to two relatively new techniques under evaluation at MSFC. These techniques involve either incremental or constant rate increases in the load applied to a precracked SE(B) specimen, monitoring the crack-opening-displacement response for indications of crack growth. The electrochemical corrosion testing demonstrated an order of magnitude greater general corrosion rate in the annealed 440C. All techniques for stress corrosion testing showed substantially better SCC resistance in the annealed material. The efficacy of the new techniques for stress corrosion testing was demonstrated both by the savings in time and the ability to better quantify SCC data.
Corrosion behavior of high-strength spring steel for high-speed railway
NASA Astrophysics Data System (ADS)
Niu, Gang; Chen, Yin-li; Wu, Hui-bin; Wang, Xuan; Tang, Di
2018-05-01
The corrosion resistance and evolution of corrosion products in medium-carbon high-strength spring steels were investigated in a neutral salt spray (5wt% NaCl solution). A formation model of γ-FeOOH and a transformation model describing the conversion of γ-FeOOH to α-FeOOH were constructed. The results indicated that, at the initial corrosion stage, the corrosion resistance was gradually improved with the addition of Cr; however, with the addition of alloying element V, the corrosion resistance decreased. These results were attributed mainly to the initial corrosion stage being closely related to the matrix microstructure parameters such as grain-boundary character and dislocation density. After the rust layer was formed at a later corrosion stage, the corrosion resistance was reinforced with the addition of Cr and V because Cr strongly influenced the composition, structure, and morphology of the corrosion products. The results presented herein show that Cr was conducive to the transformation of γ-FeOOH into α-FeOOH. Moreover, V and Cr exhibited obvious synergy and were enriched in the inner layer of the corrosion products.
Dual Use Corrosion Inhibitor and Penetrant for Anomaly Detection in Neutron/X Radiography
NASA Technical Reports Server (NTRS)
Hall, Phillip B. (Inventor); Novak, Howard L. (Inventor)
2004-01-01
A dual purpose corrosion inhibitor and penetrant composition sensitive to radiography interrogation is provided. The corrosion inhibitor mitigates or eliminates corrosion on the surface of a substrate upon which the corrosion inhibitor is applied. In addition, the corrosion inhibitor provides for the attenuation of a signal used during radiography interrogation thereby providing for detection of anomalies on the surface of the substrate.
Yang, Fan; Shi, Baoyou; Gu, Junnong; Wang, Dongsheng; Yang, Min
2012-10-15
The corrosion scales on iron pipes could have great impact on the water quality in drinking water distribution systems (DWDS). Unstable and less protective corrosion scale is one of the main factors causing "discolored water" issues when quality of water entering into distribution system changed significantly. The morphological and physicochemical characteristics of corrosion scales formed under different source water histories in duration of about two decades were systematically investigated in this work. Thick corrosion scales or densely distributed corrosion tubercles were mostly found in pipes transporting surface water, but thin corrosion scales and hollow tubercles were mostly discovered in pipes transporting groundwater. Magnetite and goethite were main constituents of iron corrosion products, but the mass ratio of magnetite/goethite (M/G) was significantly different depending on the corrosion scale structure and water source conditions. Thick corrosion scales and hard shell of tubercles had much higher M/G ratio (>1.0), while the thin corrosion scales had no magnetite detected or with much lower M/G ratio. The M/G ratio could be used to identify the characteristics and evaluate the performances of corrosion scales formed under different water conditions. Compared with the pipes transporting ground water, the pipes transporting surface water were more seriously corroded and could be in a relatively more active corrosion status all the time, which was implicated by relatively higher siderite, green rust and total iron contents in their corrosion scales. Higher content of unstable ferric components such as γ-FeOOH, β-FeOOH and amorphous iron oxide existed in corrosion scales of pipes receiving groundwater which was less corroded. Corrosion scales on groundwater pipes with low magnetite content had higher surface area and thus possibly higher sorption capacity. The primary trace inorganic elements in corrosion products were Br and heavy metals. Corrosion products obtained from pipes transporting groundwater had higher levels of Br, Ti, Ba, Cu, Sr, V, Cr, La, Pb and As. Copyright © 2012 Elsevier Ltd. All rights reserved.
The Tension and Puncture Properties of HDPE Geomembrane under the Corrosion of Leachate.
Xue, Qiang; Zhang, Qian; Li, Zhen-Ze; Xiao, Kai
2013-09-17
To investigate the gradual failure of high-density polyethylene (HDPE) geomembrane as a result of long-term corrosion, four dynamic corrosion tests were conducted at different temperatures and durations. By combining tension and puncture tests, we systematically studied the variation law of tension and puncture properties of the HDPE geomembrane under different corrosion conditions. Results showed that tension and puncture failure of the HDPE geomembrane was progressive, and tensile strength in the longitudinal grain direction was evidently better than that in the transverse direction. Punctures appeared shortly after puncture force reached the puncture strength. The tensile strength of geomembrane was in inversely proportional to the corrosion time, and the impact of corrosion was more obvious in the longitudinal direction than transverse direction. As corrosion time increased, puncture strength decreased and corresponding deformation increased. As with corrosion time, the increase of corrosion temperature induced the decrease of geomembrane tensile strength. Tensile and puncture strength were extremely sensitive to temperature. Overall, residual strength had a negative correlation with corrosion time or temperature. Elongation variation increased initially and then decreased with the increase in temperature. However, it did not show significant law with corrosion time. The reduction in puncture strength and the increase in puncture deformation had positive correlations with corrosion time or temperature. The geomembrane softened under corrosion condition. The conclusion may be applicable to the proper designing of the HDPE geomembrane in landfill barrier system.
Predicting concrete corrosion of sewers using artificial neural network.
Jiang, Guangming; Keller, Jurg; Bond, Philip L; Yuan, Zhiguo
2016-04-01
Corrosion is often a major failure mechanism for concrete sewers and under such circumstances the sewer service life is largely determined by the progression of microbially induced concrete corrosion. The modelling of sewer processes has become possible due to the improved understanding of in-sewer transformation. Recent systematic studies about the correlation between the corrosion processes and sewer environment factors should be utilized to improve the prediction capability of service life by sewer models. This paper presents an artificial neural network (ANN)-based approach for modelling the concrete corrosion processes in sewers. The approach included predicting the time for the corrosion to initiate and then predicting the corrosion rate after the initiation period. The ANN model was trained and validated with long-term (4.5 years) corrosion data obtained in laboratory corrosion chambers, and further verified with field measurements in real sewers across Australia. The trained model estimated the corrosion initiation time and corrosion rates very close to those measured in Australian sewers. The ANN model performed better than a multiple regression model also developed on the same dataset. Additionally, the ANN model can serve as a prediction framework for sewer service life, which can be progressively improved and expanded by including corrosion rates measured in different sewer conditions. Furthermore, the proposed methodology holds promise to facilitate the construction of analytical models associated with corrosion processes of concrete sewers. Copyright © 2016 Elsevier Ltd. All rights reserved.
Corrosion and Protection of Metal in the Seawater Desalination
NASA Astrophysics Data System (ADS)
Hou, Xiangyu; Gao, Lili; Cui, Zhendong; Yin, Jianhua
2018-01-01
Seawater desalination develops rapid for it can solve water scarcity efficiently. However, corrosion problem in the seawater desalination system is more serious than that in normal water. So, it is important to pay attention to the corrosion and protection of metal in seawater desalination. The corrosion characteristics and corrosion types of metal in the seawater desalination system are introduced in this paper; In addition, corrosion protect methods and main influencing factors are stated, the latest new technologies about anti-corrosion with quantum energy assisted and magnetic inhibitor are presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moon, Joonoh, E-mail: mjo99@kims.re.kr; Ha, Heon-Young; Lee, Tae-Ho
2013-08-15
The pitting corrosion and interphase corrosion behaviors in high heat input welded heat-affected zone (HAZ) of a metastable high-nitrogen Fe–18Cr–10Mn–N austenitic stainless steel were explored through electrochemical tests. The HAZs were simulated using Gleeble simulator with high heat input welding condition of 300 kJ/cm and the peak temperature of the HAZs was changed from 1200 °C to 1350 °C, aiming to examine the effect of δ-ferrite formation on corrosion behavior. The electrochemical test results show that both pitting corrosion resistance and interphase corrosion resistance were seriously deteriorated by δ-ferrite formation in the HAZ and their aspects were different with increasingmore » δ-ferrite fraction. The pitting corrosion resistance was decreased by the formation of Cr-depleted zone along δ-ferrite/austenite (γ) interphase resulting from δ-ferrite formation; however it didn't depend on δ-ferrite fraction. The interphase corrosion resistance depends on the total amount of Cr-depleted zone as well as ferrite area and thus continuously decreased with increasing δ-ferrite fraction. The different effects of δ-ferrite fraction on pitting corrosion and interphase corrosion were carefully discussed in terms of alloying elements partitioning in the HAZ based on thermodynamic consideration. - Highlights: • Corrosion behavior in the weld HAZ of high-nitrogen austenitic alloy was studied. • Cr{sub 2}N particle was not precipitated in high heat input welded HAZ of tested alloy. • Pitting corrosion and interphase corrosion show a different behavior. • Pitting corrosion resistance was affected by whether or not δ-ferrite forms. • Interphase corrosion resistance was affected by the total amount of δ-ferrite.« less
Rylska, Dorota; Sokołowski, Grzegorz; Sokołowski, Jerzy; Łukomska-Szymańska, Monika
2017-01-01
The purpose of the study was to evaluate corrosion resistance of Wirobond C® alloy after chemical passivation treatment. The alloy surface undergone chemical passivation treatment in four different media. Corrosion studies were carried out by means of electrochemical methods in saline solution. Corrosion effects were determined using SEM. The greatest increase in the alloy polarization resistance was observed for passive layer produced in Na2SO4 solution with graphite. The same layer caused the highest increase in corrosion current. Generally speaking, the alloy passivation in Na2SO4 solution with graphite caused a substantial improvement of the corrosion resistance. The sample after passivation in Na2SO4 solution without graphite, contrary to others, lost its protective properties along with successive anodic polarization cycles. The alloy passivation in Na3PO4 solution with graphite was the only one that caused a decrease in the alloy corrosion properties. The SEM studies of all samples after chemical passivation revealed no pit corrosion - in contrast to the sample without any modification. Every successive polarization cycle in anodic direction of pure Wirobond C® alloy enhances corrosion resistance shifting corrosion potential in the positive direction and decreasing corrosion current value. The chemical passivation in solutions with low pH values decreases susceptibility to electrochemical corrosion of Co-Cr dental alloy. The best protection against corrosion was obtained after chemical passivation of Wirobond C® in Na2SO4 solution with graphite. Passivation with Na2SO4 in solution of high pH does not cause an increase in corrosion resistance of WIROBOND C. Passivation process increases alloy resistance to pit corrosion.
Review of corrosion in 10- and 14-ton mild steel depleted UF{sub 6} storage cylinders
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lykins, M.L.
1995-08-01
A literature review was conducted to determine the type, extent and severity of corrosion found in the 10- and 14-ton mild steel depleted UF{sub 6} storage cylinders. Also discussed in this review is corrosion found in the valves and plugs used in the cylinders. Corrosion of the cylinders is a gradual process which occurs slowly over time. Understanding corrosion of the cylinders is an important concern for long term storage of the UF{sub 6} in the cylinder yards, as well as the final disposition of the depleted UF{sub 6} tails inventory in the future. The following conclusions are made frommore » the literature review: (1) The general external corrosion rate of the cylinders is about 1 to 2 mils per year (1 mil = 0.001{double_prime}). The highest general external corrosion rate was over 5 mpy on the 48G type cylinders. (2) General internal corrosion from the depleted UF{sub 6} is negligible under normal storage conditions. Crevice corrosion can occur at the cylinder/saddle interface from the retention of water in this area. Crevice corrosion can occur at the cylinder/skirt interface on the older skirted cylinders due to the lack of water drainage in this area. Crevice corrosion can occur on cylinders that have been in ground contact. Crevice corrosion and galvanic corrosion can occur where the stainless steel I.D. nameplates are attached to the cylinder. The packing nuts on the bronze one-inch valves used in the cylinders are susceptible to stress corrosion cracking (SCC). Mechanical damage from routine handling can lead to a breach in a cylinder with subsequent accelerated corrosion of the mild steel due to attack from HF and other UF{sub 6} hydrolysis by-products.« less
NASA Astrophysics Data System (ADS)
Tang, Fujian
This study is aimed (a) to statistically characterize the corrosion-induced deterioration process of reinforced concrete structures (concrete cracking, steel mass loss, and rebar-concrete bond degradation), and (b) to develop and apply three types of enamel-coated steel bars for improved corrosion resistance of the structures. Commercially available pure enamel, mixed enamel with 50% calcium silicate, and double enamel with an inner layer of pure enamel and an outer layer of mixed enamel were considered as various steel coatings. Electrochemical tests were respectively conducted on steel plates, smooth bars embedded in concrete, and deformed bars with/without concrete cover in 3.5 wt.% NaCl or saturated Ca(OH)2 solution. The effects of enamel microstructure, coating thickness variation, potential damage, mortar protection, and corrosion environment on corrosion resistance of the steel members were investigated. Extensive test results indicated that corrosion-induced concrete cracking can be divided into four stages that gradually become less correlated with corrosion process over time. The coefficient of variation of crack width increases with the increasing level of corrosion. Corrosion changed the cross section area instead of mechanical properties of steel bars. The bond-slip behavior between the corroded bars and concrete depends on the corrosion level and distribution of corrosion pits. Although it can improve the chemical bond with concrete and steel, the mixed enamel coating is the least corrosion resistant. The double enamel coating provides the most consistent corrosion performance and is thus recommended to coat reinforcing steel bars for concrete structures applied in corrosive environments. Corrosion pits in enamel-coated bars are limited around damage locations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiabin, Han; Carey, James W; Zhang, Jinsuo
2011-01-27
Traditional corrosion inhibitors are bio-toxic chemicals with organic components that bond to the fresh metal surface and thus isolate them from corrosive environments. The shortcoming of these inhibitors is that they are less effective in high-temperature and high-pressure environments, and where corrosion scale is formed or particulates are deposited. In this paper, we describe a novel green inorganic inhibitor made of environmentally friendly and cost-effective geo-material that was developed for high-temperature and high-pressure environments, particularly under scale-forming conditions. It inhibits corrosion by enhancing the protectiveness of corrosion scale. In contrast to traditional corrosion inhibitors which are efficient for bare surfacemore » corrosion but not effective with scale, the novel inhibitor has no effect on bare surface corrosion but greatly improves corrosion inhibition under scale-formation conditions. This is because a homogeneous scale doped with inhibitor component forms. This enhanced corrosion scale demonstrated excellent protection against corrosion. In high-pressure CO{sub 2} systems (pCO{sub 2}=10 Mpa, T=50 C and [NaCl]=1 wt%) without inhibitor, the bare-surface corrosion rate decreases from ca. 10 mm/y to 0.3 mm/year due to formation of scale. Application of a six hundred ppm solution ofthe new inorganic inhibitor reduced the corrosion rate to 0.01 mm/year, an additional factor of 30. The current inhibitor product was designed for application to CO{sub 2} systems that form corrosion scale, including but not limited to oil and gas wells, offshore production of oil and gas, CO{sub 2} sequestration and enhanced geothermal production involving CO{sub 2}.« less
Flow-induced corrosion of absorbable magnesium alloy: In-situ and real-time electrochemical study
Wang, Juan; Jang, Yongseok; Wan, Guojiang; Giridharan, Venkataraman; Song, Guang-Ling; Xu, Zhigang; Koo, Youngmi; Qi, Pengkai; Sankar, Jagannathan; Huang, Nan; Yun, Yeoheung
2016-01-01
An in-situ and real-time electrochemical study in a vascular bioreactor was designed to analyze corrosion mechanism of magnesium alloy (MgZnCa) under mimetic hydrodynamic conditions. Effect of hydrodynamics on corrosion kinetics, types, rates and products was analyzed. Flow-induced shear stress (FISS) accelerated mass and electron transfer, leading to an increase in uniform and localized corrosions. FISS increased the thickness of uniform corrosion layer, but filiform corrosion decreased this layer resistance at high FISS conditions. FISS also increased the removal rate of localized corrosion products. Impedance-estimated and linear polarization-measured polarization resistances provided a consistent correlation to corrosion rate calculated by computed tomography. PMID:28626241
Flow-induced corrosion of absorbable magnesium alloy: In-situ and real-time electrochemical study.
Wang, Juan; Jang, Yongseok; Wan, Guojiang; Giridharan, Venkataraman; Song, Guang-Ling; Xu, Zhigang; Koo, Youngmi; Qi, Pengkai; Sankar, Jagannathan; Huang, Nan; Yun, Yeoheung
2016-03-01
An in-situ and real-time electrochemical study in a vascular bioreactor was designed to analyze corrosion mechanism of magnesium alloy (MgZnCa) under mimetic hydrodynamic conditions. Effect of hydrodynamics on corrosion kinetics, types, rates and products was analyzed. Flow-induced shear stress (FISS) accelerated mass and electron transfer, leading to an increase in uniform and localized corrosions. FISS increased the thickness of uniform corrosion layer, but filiform corrosion decreased this layer resistance at high FISS conditions. FISS also increased the removal rate of localized corrosion products. Impedance-estimated and linear polarization-measured polarization resistances provided a consistent correlation to corrosion rate calculated by computed tomography.
Corrosion products of carbonation induced corrosion in existing reinforced concrete facades
DOE Office of Scientific and Technical Information (OSTI.GOV)
Köliö, Arto; Honkanen, Mari; Lahdensivu, Jukka
Active corrosion in reinforced concrete structures is controlled by environmental conditions and material properties. These factors determine the corrosion rate and type of corrosion products which govern the total achieved service life. The type and critical amount of corrosion products were studied by electron microscopy and X-ray diffractometry on concrete and reinforcement samples from existing concrete facades on visually damaged locations. The corrosion products in outdoor environment exposed concrete facades are mostly hydroxides (Feroxyhite, Goethite and Lepidocrocite) with a volume ratio to Fe of approximately 3. The results can be used to calibrate calculation of the critical corrosion penetration ofmore » concrete facade panels.« less
Gascoyne, Trevor C; Dyrkacz, Richard M; Turgeon, Thomas R; Burnell, Colin D; Wyss, Urs P; Brandt, Jan-M
2014-10-01
Eight retrieved metal-on-metal total hip replacements displayed corrosion damage along the cobalt-chromium alloy liner taper junction with the Ti alloy acetabular shell. Scanning electron microscopy indicated the primary mechanism of corrosion to be grain boundary and associated crevice corrosion, which was likely accelerated through mechanical micromotion and galvanic corrosion resulting from dissimilar alloys. Coordinate measurements revealed up to 4.3mm(3) of the cobalt-chromium alloy taper surface was removed due to corrosion, which is comparable to previous reports of corrosion damage on head-neck tapers. The acetabular liner-shell taper appears to be an additional source of metal corrosion products in modular total hip replacements. Patients with these prostheses should be closely monitored for signs of adverse reaction towards corrosion by-products. Copyright © 2014 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
DUNCAN JB; COOKE GA
2007-03-22
Tank Farms Operations removed an electrochemical noise probe from Tank 241-AN-107. In the field, the probe was cut into four sections, wrapped, and placed in a 55-gallon drum, This drum was delivered to the 222-S Laboratory. The 222 S Laboratory unpackaged the sections of the AN-107 electrochemical noise probe and examined the material for evidence of corrosion. Each of the four sections contained three C-ring and three bullet specimens. The specimens were examined for pitting corrosion, crevice corrosion, and stress corrosion cracking. No evidence of stress corrosion cracking was found in the stressed C-ring specimens. Minor pitting was evident onmore » some surfaces. Crevice corrosion was the dominant type of corrosion observed.« less
Catt, Kasey; Li, Huaxiu; Cui, X Tracy
2017-01-15
Magnesium (Mg) is a promising biodegradable implant material because of its appropriate mechanical properties and safe degradation products. However, in vivo corrosion speed and hydrogen gas production need to be controlled for uses in biomedical applications. Here we report the development of a conducting polymer 3,4-ethylenedioxythiphene (PEDOT) and graphene oxide (GO) composite coating as a corrosion control layer. PEDOT/GO was electropolymerized on Mg samples in ethanol media. The coated Mg samples were subjected to various corrosion tests. The PEDOT/GO coating significantly reduced the rate of corrosion as evidenced by lower Mg ion concentration and pH of the corrosion media. In addition, the coating decreased the evolved hydrogen. Electrochemical analysis of the corroding samples showed more positive corrosion potential, a decreased corrosion current, and an increase in the polarization resistance. PEDOT/GO corrosion protection is attributed to three factors; an initial passive layer preventing solution ingress, buildup of negative charges in the film, and formation of corrosion protective Mg phosphate layer through redox coupling with Mg corrosion. To explore the biocompatibility of the coated implants in vitro, corrosion media from PEDOT/GO coated or uncoated Mg samples were exposed to cultured neurons where PEDOT/GO coated samples showed decreased toxicity. These results suggest that PEDOT/GO coating will be an effective treatment for controlling corrosion of Mg based medical implants. Coating Mg substrates with a PEDOT/GO composite coating showed a significant decrease in corrosion rate. While conducting polymer coatings have been used to prevent corrosion on various metals, there has been little work on the use of these coatings for Mg. Additionally, to our knowledge, there has not been a report of the combined used of conducting polymer and GO as a corrosion control layer. Corrosion control is attributed to an initial barrier layer followed by electrochemical coupling of the PEDOT/GO coating with the substrate to facilitate the formation of a protective phosphate layer. This coupling also resulted in a decrease in hydrogen produced during corrosion, which could further improve the host tissue integration of Mg implants. This work elaborates on the potential for electroactive polymers to serve as corrosion control methods. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
49 CFR 192.461 - External corrosion control: Protective coating.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Protective coating... for Corrosion Control § 192.461 External corrosion control: Protective coating. (a) Each external protective coating, whether conductive or insulating, applied for the purpose of external corrosion control...
49 CFR 193.2627 - Atmospheric corrosion control.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false Atmospheric corrosion control. 193.2627 Section... LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2627 Atmospheric corrosion... atmospheric corrosion by— (a) Material that has been designed and selected to resist the corrosive atmosphere...
49 CFR 193.2631 - Internal corrosion control.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false Internal corrosion control. 193.2631 Section 193... GAS FACILITIES: FEDERAL SAFETY STANDARDS Maintenance § 193.2631 Internal corrosion control. Each component that is subject to internal corrosive attack must be protected from internal corrosion by— (a...
49 CFR 192.461 - External corrosion control: Protective coating.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Protective coating... for Corrosion Control § 192.461 External corrosion control: Protective coating. (a) Each external protective coating, whether conductive or insulating, applied for the purpose of external corrosion control...
DOT National Transportation Integrated Search
1998-06-01
We used a simulated concrete pore water solution to evaluate the corrosion protection performance of concrete corrosion-inhibiting admixtures and epoxy-coated reinforcing bars (ECR). We evaluated three commercial corrosion inhibitors, ECR from three ...
Corrosion probe. Innovative technology summary report
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
Over 253 million liters of high-level waste (HLW) generated from plutonium production is stored in mild steel tanks at the Department of Energy (DOE) Hanford Site. Corrosion monitoring of double-shell storage tanks (DSTs) is currently performed at Hanford using a combination of process knowledge and tank waste sampling and analysis. Available technologies for corrosion monitoring have progressed to a point where it is feasible to monitor and control corrosion by on-line monitoring of the corrosion process and direct addition of corrosion inhibitors. The electrochemical noise (EN) technique deploys EN-based corrosion monitoring probes into storage tanks. This system is specifically designedmore » to measure corrosion rates and detect changes in waste chemistry that trigger the onset of pitting and cracking. These on-line probes can determine whether additional corrosion inhibitor is required and, if so, provide information on an effective end point to the corrosion inhibitor addition procedure. This report describes the technology, its performance, its application, costs, regulatory and policy issues, and lessons learned.« less
Stress corrosion cracking of an aluminum alloy used in external fixation devices.
Cartner, Jacob L; Haggard, Warren O; Ong, Joo L; Bumgardner, Joel D
2008-08-01
Treatment for compound and/or comminuted fractures is frequently accomplished via external fixation. To achieve stability, the compositions of external fixators generally include aluminum alloy components due to their high strength-to-weight ratios. These alloys are particularly susceptible to corrosion in chloride environments. There have been several clinical cases of fixator failure in which corrosion was cited as a potential mechanism. The aim of this study was to evaluate the effects of physiological environments on the corrosion susceptibility of aluminum 7075-T6, since it is used in orthopedic external fixation devices. Electrochemical corrosion curves and alternate immersion stress corrosion cracking tests indicated aluminum 7075-T6 is susceptible to corrosive attack when placed in physiological environments. Pit initiated stress corrosion cracking was the primary form of alloy corrosion, and subsequent fracture, in this study. Anodization of the alloy provided a protective layer, but also caused a decrease in passivity ranges. These data suggest that once the anodization layer is disrupted, accelerated corrosion processes occur. (c) 2007 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Chen, He; Yang, Yueguang; Su, Guolei; Wang, Xiaoqing; Zhang, Hourong; Sun, Xiaoyu; Fan, Youping
2017-09-01
There are increasingly serious electrocorrosion phenomena on insulator hardware caused by direct current transmission due to the wide-range popularization of extra high voltage direct current transmission engineering in our country. Steel foot corrosion is the main corrosion for insulators on positive polarity side of transmission lines. On one hand, the corrosion leads to the tapering off of steel foot diameter, having a direct influence on mechanical property of insulators; on the other hand, in condition of corrosion on steel foot wrapped in porcelain ware, the volume of the corrosion product is at least 50% more than that of the original steel foot, leading to bursting of porcelain ware, threatening safe operation of transmission lines. Therefore, it is necessary to conduct research on the phenomenon and propose feasible measures for corrosion inhibition. Starting with the corrosion mechanism, this article proposes two measures for corrosion inhibition, and verifies the inhibition effect in laboratory conditions, providing reference for application in engineering.
NASA Astrophysics Data System (ADS)
Esnault, L.; Jullien, M.; Mustin, C.; Bildstein, O.; Libert, M.
In deep geological environments foreseen for the disposal of radioactive waste, metallic containers will undergo anaerobic corrosion. In this context, the formation of corrosion products such as magnetite may reduce the rate of corrosion processes through the formation of a protective layer. This study aims at determining the direct impact of iron-reducing bacteria (IRB) activity on the stability of corrosion protective layers. Batch experiments investigating iron corrosion processes including the formation of secondary magnetite and its subsequent alteration in the presence of IRB show the bacteria ability to use structural Fe(III) for respiration which leads to the sustainment of a high corrosion rate. With the bio-reduction of corrosion products such as magnetite, and H 2 as electron donor, IRB promote the reactivation of corrosion processes in corrosive environments by altering the protective layer. This phenomenon could have a major impact on the long-term stability of metallic compounds involved in multi-barrier system for high-level radioactive waste containment.
Study of development and utilization of a multipurpose atmospheric corrosion sensor
NASA Technical Reports Server (NTRS)
Diwan, Ravinder M.; Raman, A.; Bhattacharya, P. K.
1994-01-01
There has been a critical need for analyzing various aspects of atmospheric corrosion and for the development of atmospheric corrosion microsensors. The project work has involved the following activities: (1) making of multielectrode corrosion monitors on dielectric substrates; (2) testing them in the laboratory for functional characteristics; (3) preparing a report on the state of the art of atmospheric corrosion sensor development around the world; and (4) corrosion testing of electrochemical changes of sensor specimens and related fog testing. The study included work on the subject of development and utilization of a multipurpose atmospheric corrosion sensor and this report is the annual report on work carried out on this research project. This has included studies on the development of sensors of two designs, stage 1 and stage 2, and with glass and alumina substrate, experimentation and development and characterization of the coating uniformity, aspects of corrosion monitoring, literature search on the corrosion sensors and their development. A state of the art report on atmospheric corrosion sensor development was prepared and submitted.
Evaluating Rebar Corrosion Using Nonlinear Ultrasound
NASA Astrophysics Data System (ADS)
Woodward, Clinton; Amin, Md. Nurul
2008-02-01
The early detection of rebar corrosion in reinforced concrete is difficult using current methods. This pilot study investigated the viability of using nonlinear ultrasound to detect the effects of rebar corrosion in its early stages. The study utilized three accelerated corrosion specimens and one control specimen. Results showed that when corrosion developed in the area isonified by a Rayleigh wave, nonlinear parameters increased. As corrosion progressed, these nonlinear parameters also increased.
The effect of vacuum annealing on corrosion resistance of titanium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chikanov, V.N.; Peshkov, V.V.; Kireev, L.S.
1994-09-01
The effect of annealing on the corrosion resistance of OT4-1 sheet titanium in 25% HCl under various air pressures and self-evacuating conditions has been investigated. From the kinetic corrosion curves it follows that the least corrosion resistance of titanium is observed after vacuum annealing. Even low residual air pressure in a chamber improves corrosion resistance. The corrosion resistance of titanium decreases with vacuum-annealing time.
Corrosion Control in the US Navy: Ships & USMC Vehicles
2014-11-18
Mr. Matthew Koch Corrosion Control & Prevention Executive Presented by E. Dail Thomas II, Consultant 18 November 2014 Corrosion Control in... control number. 1. REPORT DATE 18 NOV 2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Corrosion Control in...and Technology DoD Corrosion Prevention and Control IPT Director, Corrosion Policy and Oversight USD Acquisition, Technology and Logistics ASD
Xu, Chen; Li, Zhiyuan; Jin, Weiliang
2013-01-01
The corrosion of reinforcements induced by chloride has resulted to be one of the most frequent causes of their premature damage. Most corrosion sensors were designed to monitor corrosion state in concrete, such as Anode-Ladder-System and Corrowatch System, which are widely used to monitor chloride ingress in marine concrete. However, the monitoring principle of these corrosion sensors is based on the macro-cell test method, so erroneous information may be obtained, especially from concrete under drying or saturated conditions due to concrete resistance taking control in macro-cell corrosion. In this paper, a fast weak polarization method to test corrosion state of reinforcements based on electrochemical polarization dynamics was proposed. Furthermore, a new corrosion sensor for monitoring the corrosion state of concrete cover was developed based on the proposed test method. The sensor was tested in cement mortar, with dry-wet cycle tests to accelerate the chloride ingress rate. The results show that the corrosion sensor can effectively monitor chloride penetration into concrete with little influence of the relative humidity in the concrete. With a reasonable corrosion sensor electrode arrangement, it seems the Ohm-drop effect measured by EIS can be ignored, which makes the tested electrochemical parameters more accurate. PMID:24084117
Xu, Chen; Li, Zhiyuan; Jin, Weiliang
2013-09-30
The corrosion of reinforcements induced by chloride has resulted to be one of the most frequent causes of their premature damage. Most corrosion sensors were designed to monitor corrosion state in concrete, such as Anode-Ladder-System and Corrowatch System, which are widely used to monitor chloride ingress in marine concrete. However, the monitoring principle of these corrosion sensors is based on the macro-cell test method, so erroneous information may be obtained, especially from concrete under drying or saturated conditions due to concrete resistance taking control in macro-cell corrosion. In this paper, a fast weak polarization method to test corrosion state of reinforcements based on electrochemical polarization dynamics was proposed. Furthermore, a new corrosion sensor for monitoring the corrosion state of concrete cover was developed based on the proposed test method. The sensor was tested in cement mortar, with dry-wet cycle tests to accelerate the chloride ingress rate. The results show that the corrosion sensor can effectively monitor chloride penetration into concrete with little influence of the relative humidity in the concrete. With a reasonable corrosion sensor electrode arrangement, it seems the Ohm-drop effect measured by EIS can be ignored, which makes the tested electrochemical parameters more accurate.
49 CFR 192.467 - External corrosion control: Electrical isolation.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Electrical isolation... for Corrosion Control § 192.467 External corrosion control: Electrical isolation. (a) Each buried or... pipeline is necessary to facilitate the application of corrosion control. (c) Except for unprotected copper...
49 CFR 192.475 - Internal corrosion control: General.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false Internal corrosion control: General. 192.475... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.475 Internal corrosion control: General. (a) Corrosive gas may not be transported by...
49 CFR 192.475 - Internal corrosion control: General.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false Internal corrosion control: General. 192.475... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.475 Internal corrosion control: General. (a) Corrosive gas may not be transported by...
49 CFR 192.477 - Internal corrosion control: Monitoring.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false Internal corrosion control: Monitoring. 192.477... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.477 Internal corrosion control: Monitoring. If corrosive gas is being transported, coupons...
49 CFR 192.467 - External corrosion control: Electrical isolation.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Electrical isolation... for Corrosion Control § 192.467 External corrosion control: Electrical isolation. (a) Each buried or... pipeline is necessary to facilitate the application of corrosion control. (c) Except for unprotected copper...
49 CFR 192.477 - Internal corrosion control: Monitoring.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false Internal corrosion control: Monitoring. 192.477... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Requirements for Corrosion Control § 192.477 Internal corrosion control: Monitoring. If corrosive gas is being transported, coupons...
Conjoint corrosion and wear in titanium alloys.
Khan, M A; Williams, R L; Williams, D F
1999-04-01
When considering titanium alloys for orthopaedic applications it is important to examine the conjoint action of corrosion and wear. In this study we investigate the corrosion and wear behaviour of Ti-6Al-4V, Ti-6Al-7Nb and Ti-13Nb-13Zr in phosphate buffered saline (PBS), bovine albumin solutions in PBS and 10% foetal calf serum solutions in PBS. The tests were performed under four different conditions to evaluate the influence of wear on the corrosion and corrosion on the wear behaviour as follows: corrosion without wear, wear-accelerated corrosion, wear in a non-corrosive environment and wear in a corrosive environment. The corrosion behaviour was investigated using cyclic polarisation studies to measure the ability of the surface to repassivate following breakdown of the passive layer. The properties of the repassivated layer were evaluated by measuring changes in the surface hardness of the alloys. The amount of wear that had occurred was assessed from weight changes and measurement of the depth of the wear scar. It was found that in the presence of wear without corrosion the wear behaviour of Ti-13Nb-13Zr was greater than that of Ti-6Al-7Nb or Ti-6Al-4V and that in the presence of proteins the wear of all three alloys is reduced. In the presence of corrosion without wear Ti-13Nb-13Zr was more corrosion resistant than Ti-6Al-7Nb which was more corrosion resistant than Ti-6Al-4V without proteins whereas in the presence of protein the corrosion resistance of Ti-13Nb-13Zr and Ti-6Al-7Nb was reduced and that of Ti-6Al-4V increased. In the presence of corrosion and wear the corrosion resistance of Ti-13Nb-13Zr is higher than that of Ti-6Al-7Nb or Ti-6Al-4V in PBS but in the presence of proteins the corrosion resistance of Ti-13Nb-13Zr and Ti-6Al-7Nb are very similar but higher than that of Ti-6Al-4V. The wear of Ti-13Nb-13Zr is lower than that of Ti-6Al-7Nb and Ti-6Al-4V with or without the presence of proteins in a corrosive environment. Therefore the overall degradation when both corrosion and wear processes are occurring is lowest for Ti-13Nb-13Zr and highest for Ti-6Al-4V and the presence of proteins reduces the degradation of all three alloys.
Vegetation of the McCormick Research Natural Area
Frederick T. Metzger
1973-01-01
The 17,000 acre McCormick tract, nestled in the Michigamme Highlands of Michigan`s Upper Peninsula, has rested quietly since the white pine loggers broke camp 70 years ago. The few occasional visitors have been hikers, fishermen, hunters, and trappers, who left little imprint on the land. The roads that eventually dissected the surrounding area never penetrated here....
Open source data logger for low-cost environmental monitoring
2014-01-01
Abstract The increasing transformation of biodiversity into a data-intensive science has seen numerous independent systems linked and aggregated into the current landscape of biodiversity informatics. This paper outlines how we can move forward with this programme, incorporating real time environmental monitoring into our methodology using low-power and low-cost computing platforms. PMID:24855446
Tracking rainfall impulses through progressively larger drainage basins in steep forested terrain
R. R. Ziemer; R. M. Rice
1990-01-01
Abstract - The precision of timing devices in modern electronic data loggers makes it possible to study the routing of water through small drainage basins having rapid responses to hydrologic impulses. Storm hyetographs were measured using digital tipping bucket rain gauges and their routing was observed at headwater piezometers located mid-slope, above a swale, and...
Project SUN (Students Understanding Nature)
NASA Technical Reports Server (NTRS)
Curley, T.; Yanow, G.
1995-01-01
Project SUN is part of NASA's 'Mission to Planet Earth' education outreach effort. It is based on development of low cost, scientifi- cally accurate instrumentation and computer interfacing, coupled with Apple II computers as dedicated data loggers. The project is com- prised of: instruments, interfacing, software, curriculum, a detailed operating manual, and a system of training at the school sites.
ERIC Educational Resources Information Center
Cooper, Rory A.; Ferretti, Eliana; Oyster, Michelle; Kelleher, Annmarie; Cooper, Rosemarie
2011-01-01
Participation is considered the most meaningful outcome of rehabilitation. The purpose of this study was to investigate whether there were correlations between wheelchair activity recorded with a data logger and community participation as measured by the Participation Survey/Mobility. Data from 16 participants were included in this study. Data…
ERIC Educational Resources Information Center
Zhang, Ruinan; Liu, Song; Yuan, Hongyan; Xiao, Dan; Choi, Martin M. F.
2012-01-01
Photocatalytic water splitting by semiconductor photocatalysts has attracted considerable attention in the past few decades. In this experiment, nanosized titanium dioxide (nano-TiO[subscript 2]) particles are used to photocatalytically split water, which is then monitored by an oxygen sensor. Sacrificial reagents such as organics (EDTA) and metal…
Subsurface pipeflow dynamics of north-coastal California swale systems
Robert R. Ziemer; Jeffrey S. Albright
1987-01-01
Abstract - Pipeflow dynamics are being studied at Caspar Creek Experimental Watershed in north-coastal California near Ft. Bragg. Pipes have been observed at depths to 2 m within trenched swales and at the heads of gullied channels in small (0.8 to 2 ha) headwater drainages. Digital data loggers connected to pressure transducers monitor discharge using calibrated...
Comparison of Field Methods and Models to Estimate Mean Crown Diameter
William A. Bechtold; Manfred E. Mielke; Stanley J. Zarnoch
2002-01-01
The direct measurement of crown diameters with logger's tapes adds significantly to the cost of extensive forest inventories. We undertook a study of 100 trees to compare this measurement method to four alternatives-two field instruments, ocular estimates, and regression models. Using the taping method as the standard of comparison, accuracy of the tested...
Interdisciplinary research can provide information for the harvesting challenges of the 1990's
Chris B. LeDoux; John E. Baumgras
1991-01-01
Management of our complex forest ecosystems in the economic and political climate of the 1990's is a challenge for planners, managers, and loggers. A multifunctional approach - using the research results of other disciplines and considering all forest uses and values - can improve the effectiveness of forest operations research. Since harvesting cost and revenue...
Information and Communication Technologies (ICT) in Biology Teaching in Slovenian Secondary Schools
ERIC Educational Resources Information Center
Sorgo, Andrej; Verckovnik, Tatjana; Kocijancic, Slavko
2010-01-01
About two-thirds of Slovene secondary schools received computers equipped with data-loggers and sensors to be used in teaching Physics, Chemistry and Biology. Later it was recognized that only a couple of Biology teachers were using the donated equipment in their classrooms or laboratories. The questionnaire, intended to investigate the situation,…
Measuring Model Rocket Engine Thrust Curves
ERIC Educational Resources Information Center
Penn, Kim; Slaton, William V.
2010-01-01
This paper describes a method and setup to quickly and easily measure a model rocket engine's thrust curve using a computer data logger and force probe. Horst describes using Vernier's LabPro and force probe to measure the rocket engine's thrust curve; however, the method of attaching the rocket to the force probe is not discussed. We show how a…
In-situ characterization of wildland fire behavior
Bret Butler; D. Jimenez; J. Forthofer; Paul Sopko; K. Shannon; Jim Reardon
2010-01-01
A system consisting of two enclosures has been developed to characterize wildand fire behavior: The first enclosure is a sensor/data logger combination that measures and records convective/radiant energy released by the fire. The second is a digital video camera housed in a fire proof enclosure that records visual images of fire behavior. Together this system provides...
Techniques for the wheeled-skidder operator
Robert L. Hartman; Harry G. Gibson; Harry G. Gibson
1970-01-01
How much production a logger gets from a logging job may depend heavily on his skidder operators. They are key men on any logging job. This is one conclusion that forestry engineers at the USDA Forest Service's Forestry Sciences Laboratory at Morgantown, West Virginia, came to after studying the operation of u-heeled skidders in mountainous Appalachian terrain....
Time Series Analysis of Water Level and Temperature in the St Louis River Estuary
Pressure and temperature loggers were deployed at 9 sites in the St Louis River estuary between 6/23 10/31 2011. A reference sensor was place on the shore to correct pressure data. Sensors were paced at <1 m depth in Allouez Bay, Superior Bay, near Hearding Island, WLSSD Bay, th...
49 CFR 195.559 - What coating material may I use for external corrosion control?
Code of Federal Regulations, 2011 CFR
2011-10-01
... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...
49 CFR 193.2629 - External corrosion control: buried or submerged components.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...
49 CFR 195.559 - What coating material may I use for external corrosion control?
Code of Federal Regulations, 2010 CFR
2010-10-01
... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...
49 CFR 192.931 - How may Confirmatory Direct Assessment (CDA) be used?
Code of Federal Regulations, 2011 CFR
2011-10-01
... corrosion or internal corrosion. (b) External corrosion plan. An operator's CDA plan for identifying external corrosion must comply with § 192.925 with the following exceptions. (1) The procedures for... criteria of scheduled action must be excavated in each ECDA region. (c) Internal corrosion plan. An...
49 CFR 192.927 - What are the requirements for using Internal Corrosion Direct Assessment (ICDA)?
Code of Federal Regulations, 2012 CFR
2012-10-01
... Corrosion Direct Assessment (ICDA)? 192.927 Section 192.927 Transportation Other Regulations Relating to... Internal Corrosion Direct Assessment (ICDA)? (a) Definition. Internal Corrosion Direct Assessment (ICDA) is... on the locations in covered segments where internal corrosion is most likely to exist. The process...
49 CFR 192.931 - How may Confirmatory Direct Assessment (CDA) be used?
Code of Federal Regulations, 2012 CFR
2012-10-01
... corrosion or internal corrosion. (b) External corrosion plan. An operator's CDA plan for identifying external corrosion must comply with § 192.925 with the following exceptions. (1) The procedures for... criteria of scheduled action must be excavated in each ECDA region. (c) Internal corrosion plan. An...
49 CFR 192.927 - What are the requirements for using Internal Corrosion Direct Assessment (ICDA)?
Code of Federal Regulations, 2014 CFR
2014-10-01
... Corrosion Direct Assessment (ICDA)? 192.927 Section 192.927 Transportation Other Regulations Relating to... Internal Corrosion Direct Assessment (ICDA)? (a) Definition. Internal Corrosion Direct Assessment (ICDA) is... on the locations in covered segments where internal corrosion is most likely to exist. The process...
49 CFR 193.2629 - External corrosion control: buried or submerged components.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...
49 CFR 192.927 - What are the requirements for using Internal Corrosion Direct Assessment (ICDA)?
Code of Federal Regulations, 2013 CFR
2013-10-01
... Corrosion Direct Assessment (ICDA)? 192.927 Section 192.927 Transportation Other Regulations Relating to... Internal Corrosion Direct Assessment (ICDA)? (a) Definition. Internal Corrosion Direct Assessment (ICDA) is... on the locations in covered segments where internal corrosion is most likely to exist. The process...
49 CFR 195.559 - What coating material may I use for external corrosion control?
Code of Federal Regulations, 2014 CFR
2014-10-01
... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...
49 CFR 193.2629 - External corrosion control: buried or submerged components.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...
49 CFR 193.2629 - External corrosion control: buried or submerged components.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: buried or submerged... corrosion control: buried or submerged components. (a) Each buried or submerged component that is subject to external corrosive attack must be protected from external corrosion by— (1) Material that has been designed...
49 CFR 192.931 - How may Confirmatory Direct Assessment (CDA) be used?
Code of Federal Regulations, 2013 CFR
2013-10-01
... corrosion or internal corrosion. (b) External corrosion plan. An operator's CDA plan for identifying external corrosion must comply with § 192.925 with the following exceptions. (1) The procedures for... criteria of scheduled action must be excavated in each ECDA region. (c) Internal corrosion plan. An...
49 CFR 195.559 - What coating material may I use for external corrosion control?
Code of Federal Regulations, 2012 CFR
2012-10-01
... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...
49 CFR 192.931 - How may Confirmatory Direct Assessment (CDA) be used?
Code of Federal Regulations, 2014 CFR
2014-10-01
... corrosion or internal corrosion. (b) External corrosion plan. An operator's CDA plan for identifying external corrosion must comply with § 192.925 with the following exceptions. (1) The procedures for... criteria of scheduled action must be excavated in each ECDA region. (c) Internal corrosion plan. An...
49 CFR 195.559 - What coating material may I use for external corrosion control?
Code of Federal Regulations, 2013 CFR
2013-10-01
... corrosion control? 195.559 Section 195.559 Transportation Other Regulations Relating to Transportation...) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Corrosion Control § 195.559 What coating material may I use for external corrosion control? Coating material for external corrosion control under...
46 CFR 129.210 - Protection from wet and corrosive environments.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Protection from wet and corrosive environments. 129.210... ELECTRICAL INSTALLATIONS General Requirements § 129.210 Protection from wet and corrosive environments. (a... exposed to corrosive environments must be of suitable construction and must be resistant to corrosion. ...
46 CFR 129.210 - Protection from wet and corrosive environments.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Protection from wet and corrosive environments. 129.210... ELECTRICAL INSTALLATIONS General Requirements § 129.210 Protection from wet and corrosive environments. (a... exposed to corrosive environments must be of suitable construction and must be resistant to corrosion. ...
46 CFR 129.210 - Protection from wet and corrosive environments.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Protection from wet and corrosive environments. 129.210... ELECTRICAL INSTALLATIONS General Requirements § 129.210 Protection from wet and corrosive environments. (a... exposed to corrosive environments must be of suitable construction and must be resistant to corrosion. ...
46 CFR 129.210 - Protection from wet and corrosive environments.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Protection from wet and corrosive environments. 129.210... ELECTRICAL INSTALLATIONS General Requirements § 129.210 Protection from wet and corrosive environments. (a... exposed to corrosive environments must be of suitable construction and must be resistant to corrosion. ...
46 CFR 129.210 - Protection from wet and corrosive environments.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Protection from wet and corrosive environments. 129.210... ELECTRICAL INSTALLATIONS General Requirements § 129.210 Protection from wet and corrosive environments. (a... exposed to corrosive environments must be of suitable construction and must be resistant to corrosion. ...
Terahertz NDE for Under Paint Corrosion Detection and Evaluation
NASA Technical Reports Server (NTRS)
Anastasi, Robert F.; Madaras, Eric I.
2005-01-01
Corrosion under paint is not visible until it has caused paint to blister, crack, or chip. If corrosion is allowed to continue then structural problems may develop. Identifying corrosion before it becomes visible would minimize repairs and costs and potential structural problems. Terahertz NDE imaging under paint for corrosion is being examined as a method to inspect for corrosion by examining the terahertz response to paint thickness and to surface roughness.
1982-12-01
Treaty Organization, Brussels, 1971), p. 449. 14. D. 0. Sprowls, T. J. Summerson, G. M. Ugianski, S. G. Epstein, and H. L. Craig , Jr., in Stress...National Association of Corrosion Engineers Houston, TX, 1972). 22. H. L. Craig , Jr. (ed.), Stress Corrosion-New Approaches, ASTM-STP- 610 (American...62. M. Hishida and H. Nakada, Corrosion 33 (11) 403 (1977). b3. D. C. Deegan and B. E. Wilde, Corrosion 34 (6), 19 (1978). 64. S. Orman, Corrosion Sci
AGARD Corrosion Handbook. Volume 2. Aircraft Corrosion Control Documents: A Descriptive Catalogue
1987-03-01
sweelb other than recommending that the use of maraging steel bolts be prohibited. However, it does provide a very good overview of the corrosion problems...as corrosion resistant steels in this manual. The metallurgy and general corrosion behavior of these steels is discussed in AGARD Corrosio.t Handbook...specifically with the selection of corrosion resistapt steels is a recommendation for prohibiting the use of maraging steel bolts in uncontrolled
NASA Astrophysics Data System (ADS)
Pan, Yuheng; Liu, Tiegen; Jiang, Junfeng; Liu, Kun; Wang, Shuang; He, Pan; Yan, Jinlin
2015-08-01
Monitoring corrosion of steel reinforcing bars is critical for the durability and safety of reinforced concrete structures. Corrosion sensors based on fiber optic have proved to exhibit meaningful benefits compared with the conventional electric ones. In recent years, Fiber Bragg Grating (FBG) has been used as a new kind of sensing element in an attempt to directly monitor the corrosion in concrete structure due to its remarkable advantages. In this paper, we present a novel kind of FBG based rebar corrosion monitoring sensor. The rebar corrosion is detected by volume expansion of the corroded rebar by transferring it to the axial strain of FBG when concrete structure is soaked in salt water. An accelerated salt water corrosion test was performed. The experiment results showed the corrosion can be monitored effectively and the corrosion rate is obtained by volume loss rate of rebar.
Application of response surface methodology method in designing corrosion inhibitor
NASA Astrophysics Data System (ADS)
Asmara, Y. P.; Athirah; Siregar, J. P.; Kurniawan, T.; Bachtiar, D.
2017-10-01
In oil and gas pipelines and offshore structure, inhibitors have been considered to be the first choice to reduce corrosion rate. There are many corrosion inhibitor compositions available in the market. To produce the best corrosion inhibitor requires many experimental data which is not efficient. These experiments used response surface methodology (RSM) to select corrosion inhibitor compositions. The experiments investigated effects of corrosion inhibition on corrosion rate of low carbon steel in 3% NaCl solution with different concentrations of selected main inhibitor compositions which are ethyl acetate (EA), ethylene glycol (EG) and sodium benzoate (SB). Corrosion rate were calculated using linear polarization resistance (LPR). All of the experiments were set in natural conditions at pH 7. MINITAB® version 15 was used for data analysis. It is shown that a quadratic model is a representative model can predict best corrosion inhibitor composition comprehensibly.
The Effect of Homogenization on the Corrosion Behavior of Al-Mg Alloy
NASA Astrophysics Data System (ADS)
Li, Yin; Hung, Yuanchun; Du, Zhiyong; Xiao, Zhengbing; Jia, Guangze
2018-04-01
The effect of homogenization on the corrosion behavior of 5083-O aluminum alloy is presented in this paper. The intergranular corrosion and exfoliation corrosion were used to characterize the discussed corrosion behavior of 5083-O aluminum alloy. The variations in the morphology, the kind and distribution of the precipitates, and the dislocation configurations in the samples after the homogenization were evaluated using optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The effects of the highly active grain boundary character distribution and the types of constituent particles on the corrosion are discussed on the basis of experimental observations. The results indicated that the corrosion behavior of 5083-O alloy was closely related to the microstructure obtained by the heat treatment. Homogenization carried out after casting had the optimal effect on the overall corrosion resistance of the material. Nevertheless, all samples could satisfy the requirements of corrosion resistance in marine applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, Yamiao; Duan, Xiaobo; Li, Yanbing
2015-08-15
Highlights: • The effects of sulfur loading on the corrosion behaviors were investigated systematically. • The corrosion became severer with increasing sulfur loading or cycle times. • The corrosion films are porous and loose and cannot prevent further reaction between lithium and polysulfides. - Abstract: The corrosion behaviors in rechargeable lithium–sulfur batteries come from the reactions between polysulfides and metal lithium anode, and they are significantly influenced by the sulfur loading. While there are limited papers reported on the effects of sulfur loading on the corrosion behaviors. In this paper, the effects have been investigated systematically. The corrosion films consistedmore » of insulating lithium ion conductors are loose and porous, so that the corrosive reactions cannot be hindered. The thickness of the corrosion layers, consequently, increased along with increasing sulfur loading or cycle times. For instance, the thickness of corrosion layers after 50 cycles was 98 μm in the cell with 5 mg sulfur while it reached up to 518 μm when the loading increased to 15 mg. The continuous deposition of corrosion products gave rise to low active materials utilization and poor cycling performance.« less
Ultimate strength performance of tankers associated with industry corrosion addition practices
NASA Astrophysics Data System (ADS)
Kim, Do Kyun; Kim, Han Byul; Zhang, Xiaoming; Li, Chen Guang; Paik, Jeom Kee
2014-09-01
In the ship and offshore structure design, age-related problems such as corrosion damage, local denting, and fatigue damage are important factors to be considered in building a reliable structure as they have a significant influence on the residual structural capacity. In shipping, corrosion addition methods are widely adopted in structural design to prevent structural capacity degradation. The present study focuses on the historical trend of corrosion addition rules for ship structural design and investigates their effects on the ultimate strength performance such as hull girder and stiffened panel of double hull oil tankers. Three types of rules based on corrosion addition models, namely historic corrosion rules (pre-CSR), Common Structural Rules (CSR), and harmonised Common Structural Rules (CSRH) are considered and compared with two other corrosion models namely UGS model, suggested by the Union of Greek Shipowners (UGS), and Time-Dependent Corrosion Wastage Model (TDCWM). To identify the general trend in the effects of corrosion damage on the ultimate longitudinal strength performance, the corrosion addition rules are applied to four representative sizes of double hull oil tankers namely Panamax, Aframax, Suezmax, and VLCC. The results are helpful in understanding the trend of corrosion additions for tanker structures
Research on A3 steel corrosion behavior of basic magnesium sulfate cement
NASA Astrophysics Data System (ADS)
Xing, Sainan; Wu, Chengyou; Yu, Hongfa; Jiang, Ningshan; Zhang, Wuyu
2017-11-01
In this paper, Tafel polarization technique is used to study the corrosion behavior of A3 steel basic magnesium sulfate, and then analyzing the ratio of raw materials cement, nitrites rust inhibitor and wet-dry cycle of basic magnesium sulfate corrosion of reinforced influence, and the steel corrosion behavior of basic magnesium sulfate compared with magnesium oxychloride cement and Portland cement. The results show that: the higher MgO/MgSO4 mole ratio will reduce the corrosion rate of steel; Too high and too low H2O/MgSO4 mole ratio may speed up the reinforcement corrosion effect; Adding a small amount of nitrite rust and corrosion inhibitor, not only can obviously reduce the alkali type magnesium sulfate in the early hydration of cement steel bar corrosion rate, but also can significantly reduce dry-wet circulation under the action of alkali type magnesium sulfate cement corrosion of reinforcement effect. Basic magnesium sulfate cement has excellent ability to protect reinforced, its long-term corrosion of reinforcement effect and was equal to that of Portland cement. Basic magnesium sulfate corrosion of reinforced is far below the level in the MOC in the case.
The Tension and Puncture Properties of HDPE Geomembrane under the Corrosion of Leachate
Xue, Qiang; Zhang, Qian; Li, Zhen-Ze; Xiao, Kai
2013-01-01
To investigate the gradual failure of high-density polyethylene (HDPE) geomembrane as a result of long-term corrosion, four dynamic corrosion tests were conducted at different temperatures and durations. By combining tension and puncture tests, we systematically studied the variation law of tension and puncture properties of the HDPE geomembrane under different corrosion conditions. Results showed that tension and puncture failure of the HDPE geomembrane was progressive, and tensile strength in the longitudinal grain direction was evidently better than that in the transverse direction. Punctures appeared shortly after puncture force reached the puncture strength. The tensile strength of geomembrane was in inversely proportional to the corrosion time, and the impact of corrosion was more obvious in the longitudinal direction than transverse direction. As corrosion time increased, puncture strength decreased and corresponding deformation increased. As with corrosion time, the increase of corrosion temperature induced the decrease of geomembrane tensile strength. Tensile and puncture strength were extremely sensitive to temperature. Overall, residual strength had a negative correlation with corrosion time or temperature. Elongation variation increased initially and then decreased with the increase in temperature. However, it did not show significant law with corrosion time. The reduction in puncture strength and the increase in puncture deformation had positive correlations with corrosion time or temperature. The geomembrane softened under corrosion condition. The conclusion may be applicable to the proper designing of the HDPE geomembrane in landfill barrier system. PMID:28788321
Runa, M J; Mathew, M T; Fernandes, M H; Rocha, L A
2015-01-01
In uncemented Ti6Al4V hip implants, the bone-stem interface is subjected to cyclic loading motion driven by the daily activities of the patients, which may lead to the complete failure of the implant in the long term. It may also compromise the proliferation and differentiation processes of osteoblastic cells (bone-forming cells). The main objective of this work is to approach for the first time the role of these organic materials on the bio-tribocorrosion mechanisms of cultured Ti6Al4V alloys. The colonized materials with MG63 osteoblastic-like cells were characterized through cell viability/proliferation and enzymatic activity. Tribocorrosion tests were performed under a reciprocating sliding configuration and low contact pressure. Electrochemical techniques were used to measure the corrosion kinetics of the system, under free potential conditions. All tests were performed at a controlled atmosphere. The morphology and topography of the wear scar were evaluated. The results showed that the presence of an osteoblastic cell layer on the implant surface significantly influences the tribocorrosion behavior of Ti6Al4V alloy. It was concluded that the cellular material was able to form an extra protective layer that inhibits further wear degradation of the alloy and decreases its corrosion tendency. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Ultrasonic cavitation erosion of 316L steel weld joint in liquid Pb-Bi eutectic alloy at 550°C.
Lei, Yucheng; Chang, Hongxia; Guo, Xiaokai; Li, Tianqing; Xiao, Longren
2017-11-01
Liquid lead-bismuth eutectic alloy (LBE) is applied in the Accelerator Driven transmutation System (ADS) as the high-power spallation neutron targets and coolant. A 19.2kHz ultrasonic device was deployed in liquid LBE at 550°C to induce short and long period cavitation erosion damage on the surface of weld joint, SEM and Atomic force microscopy (AFM) were used to map out the surface properties, and Energy Dispersive Spectrometer (EDS) was applied to the qualitative and quantitative analysis of elements in the micro region of the surface. The erosion mechanism for how the cavitation erosion evolved by studying the element changes, their morphology evolution, the surface hardness and the roughness evolution, was proposed. The results showed that the pits, caters and cracks appeared gradually on the erode surface after a period of cavitation. The surface roughness increased along with exposure time. Work hardening by the bubbles impact in the incubation stage strengthened the cavitation resistance efficiently. The dissolution and oxidation corrosion and cavitation erosion that simultaneously happened in liquid LBE accelerated corrosion-erosion process, and these two processes combined to cause more serious damage on the material surface. Contrast to the performance of weld metal, base metal exhibited a much better cavitation resistance. Copyright © 2017. Published by Elsevier B.V.
NASA Technical Reports Server (NTRS)
Stegman, Thomas W.; Wilson, Mark E.; Glasscock, Brad; Holt, Mike
2014-01-01
The International Space Station (ISS) Internal Active Thermal Control System (IATCS) experienced a number of chemical changes driven by system absorption of CO2 which altered the coolant’s pH. The natural effects of the decrease in pH from approximately 9.2 to less than 8.4 had immediate consequences on system corrosion rates and corrosion product interactions with specified coolant constituents. The alkalinity of the system was increased through the development and implementation of a carbonate/bicarbonate buffer that would increase coolant pH to 9.0 – 10.0 and maintain pH above 9.0 in the presence of ISS cabin concentrations of CO2 up to twenty times higher than ground concentrations. This paper defines how a carbonate/bicarbonate buffer works in an open carbon dioxide system and summarizes the analyses performed on the buffer for safe and effective application in the on-orbit system. The importance of the relationship between the cabin environment and the IATCS is demonstrated as the dominant factor in understanding the system chemistry and pH trends before and after addition of the carbonate/bicarbonate buffer. The paper also documents the corollary electrochemical and chemical reactions the system has experienced and the rationale for remediation of these effects with the addition of the carbonate/bicarbonate buffer.
The Effects of Alloy Chemistry on Localized Corrosion of Austenitic Stainless Steels
NASA Astrophysics Data System (ADS)
Sapiro, David O.
This study investigated localized corrosion behavior of austenitic stainless steels under stressed and unstressed conditions, as well as corrosion of metallic thin films. While austenitic stainless steels are widely used in corrosive environments, they are vulnerable to pitting and stress corrosion cracking (SCC), particularly in chloride-containing environments. The corrosion resistance of austenitic stainless steels is closely tied to the alloying elements chromium, nickel, and molybdenum. Polarization curves were measured for five commercially available austenitic stainless steels of varying chromium, nickel, and molybdenum content in 3.5 wt.% and 25 wt.% NaCl solutions. The alloys were also tested in tension at slow strain rates in air and in a chloride environment under different polarization conditions to explore the relationship between the extent of pitting corrosion and SCC over a range of alloy content and environment. The influence of alloy composition on corrosion resistance was found to be consistent with the pitting resistance equivalent number (PREN) under some conditions, but there were also conditions under which the model did not hold for certain commercial alloy compositions. Monotonic loading was used to generate SCC in in 300 series stainless steels, and it was possible to control the failure mode through adjusting environmental and polarization conditions. Metallic thin film systems of thickness 10-200 nm are being investigated for use as corrosion sensors and protective coatings, however the corrosion properties of ferrous thin films have not been widely studied. The effects of film thickness and substrate conductivity were examined using potentiodynamic polarization and scanning vibrating electrode technique (SVET) on iron thin films. Thicker films undergo more corrosion than thinner films in the same environment, though the corrosion mechanism is the same. Conductive substrates encourage general corrosion, similar to that of bulk iron, while insulating substrates supported only localized corrosion.
Long-term corrosion of a Ga-containing restorative material.
Sarkar, N K; Moiseyeva, R; Berzins, D W; Osborne, J W
2000-03-01
The aim was to simulate and characterize the long-term corrosion of a Ga-containing alloy (Galloy, SDI). To induce corrosion, cylindrical specimens, 8 x 4 mm, of the material were subject to potentiostatic polarization at -0.1 V (SCE) in a phosphated buffered saline (PBS) solution at 20 degrees C for d. The current-time transients during polarization were recorded and the corresponding anodic charge, Q, was calculated. Parallel potentiostatic corrosion tests in a Cl-free PBS solution were also conducted to demonstrate the significance of the Cl- ion in corrosion. In addition, potentiodynamic anodic polarization tests were performed to characterize the overall corrosion behavior of the alloy in both electrolytes. The external and internal corroded layers, formed during potentiostatic corrosion in PBS, were measured by optical microscopy. SEM and EDXA were used to characterize the morphology and composition of the potentiostatically polarized surfaces. Galloy was passive in Cl-free PBS. The Cl- ion in PBS destroyed passivity and initiated a "dissolution-precipitation" type reaction during potentiostatic corrosion. The latter led to circumferential internal corrosion and growth of a layer of external corrosion products. The thickness of the internal and external corrosion layers was 0.77 +/- 0.07 and 0.86 +/- 0.37 mm, respectively. The Q value (89.3 +/- 13.7 C/cm2) in PBS was about two orders of magnitude higher than that (0.66 +/- 0.24 C/cm2) in Cl-free PBS. The corrosion products contained Sn, Ga, In, Cu, O and Cl. Massive internal and external corrosion in a Cl-containing medium as in saliva, accumulation of corrosion products at the cavity wall, and the consequent stress build-up contribute to post-operative pain, tooth straining, marginal breakdown and fractured teeth reported with the clinical use of Galloy.
Kassab, Elisa J; Gomes, José Ponciano
2013-09-01
To assess the influence of fluoride concentration on the corrosion behavior of nickel titanium (NiTi) superelastic wire and to compare the corrosion resistance of NiTi with that of beta titanium alloy in physiological solution with and without addition of fluoride. NiTi corrosion resistance was investigated through electrochemical impedance spectroscopy and anodic polarization in sodium chloride (NaCl 0.15 M) with and without addition of 0.02 M sodium fluoride (NaF), and the results were compared with those associated with beta titanium. The influence of fluoride concentration on NiTi corrosion behavior was assessed in NaCl (0.15 M) with and without 0.02, 0.04, 0.05, 0.07, and 0.12 M NaF solution. Galvanic corrosion between NiTi and beta titanium were investigated. All samples were characterized by scanning electron microscopy. Polarization resistance decreased when NaF concentration was increased, and, depending on NaF concentration, NiTi can suffer localized or generalized corrosion. In NaCl solution with 0.02 M NaF, NiTi suffer localized corrosion, while beta titanium alloys remained passive. Current values near zero were observed by galvanic coupling of NiTi and beta titanium. There is a decrease in NiTi corrosion resistance in the presence of fluoride. The corrosion behavior of NiTi alloy depends on fluoride concentration. When 0.02 and 0.04 M of NaF were added to the NaCl solution, NiTi presented localized corrosion. When NaF concentration increased to 0.05, 0.07, and 0.12 M, the alloy presented general corrosion. NiTi corrosion resistance behavior is lower than that of beta titanium. Galvanic coupling of these alloys does not increase corrosion rates.
Sun, Jianbo; Sun, Chong; Lin, Xueqiang; Cheng, Xiangkun; Liu, Huifeng
2016-01-01
The novel Cr-containing low alloy steels have exhibited good corrosion resistance in CO2 environment, mainly owing to the formation of Cr-enriched corrosion film. In order to evaluate whether it is applicable to the CO2 and H2S coexistence conditions, the corrosion behavior of low-chromium steels in CO2-H2S environment with high pressure and high temperature was investigated using weight loss measurement and surface characterization. The results showed that P110 steel suffered localized corrosion and both 3Cr-P110 and 5Cr-P110 steels exhibited general corrosion. However, the corrosion rate of 5Cr-P110 was the highest among them. The corrosion process of the steels was simultaneously governed by CO2 and H2S. The outer scales on the three steels mainly consisted of FeS1−x crystals, whereas the inner scales on Cr-containing steels comprised of amorphous FeS1−x, Cr(OH)3 and FeCO3, in contrast with the amorphous FeS1−x and FeCO3 mixture film of P110 steel. The more chromium the steel contains, the more chromium compounds the corrosion products contain. The addition of chromium in steels increases the uniformity of the Cr-enriched corrosion scales, eliminates the localized corrosion, but cannot decrease the general corrosion rates. The formation of FeS1−x may interfere with Cr-enriched corrosion scales and lowering the corrosion performance of 3Cr-P110 and 5Cr-P110 steels. PMID:28773328
The Role of Stress in the Corrosion Cracking of Aluminum Alloys
2013-03-01
Corrosion IGSCC Intergranular Stress Corrosion Cracking NAMLT Nitric Acid Mass Loss Test SCC Stress Corrosion Cracking TGSCC Transgranular Stress...solution at a nitric acid mass loss test (NAMLT) value of 49 mg/cm 2 with an applied voltage of 0.73 VSCE. They also showed that the amount of corrosion ...for determining the susceptibility to intergranualr corrosion of 5XXX series aluminum alloys by mass loss after exposure to nitric acid ," vol.
NASA Astrophysics Data System (ADS)
Sun, Ze; Zhang, Donghui; Yan, Baoxu; Kong, Dejun
2018-02-01
An arc sprayed aluminum (Al) coating on S355 steel was processed using a laser remelting (LR). The microstructures, chemical element composition, and phases of the obtained Al coating were analyzed using a field mission scanning electronic microscope (FESEM), energy dispersive spectrometer (EDS), and X-ray diffractometer (XRD), respectively, and the residual stresses were measured using an X-ray diffraction stress tester. The immersion corrosion tests and potentiodynamic polarization of Al coating in 3.5% NaCl solution were performed to investigate the effects of LR on its immersion corrosion behaviors, and the corrosion mechanism of Al coating was also discussed. The results show that the arc sprayed Al coating is composed of Al phase, while that by LR is composed of Al-Fe and AlO4FeO6 phases, and the porosities and cracks in the arc sprayed Al coating are eliminated by LR, The residual stress of arc sprayed Al coating is -5.6 ± 18 MPa, while that after LR is 137.9 ± 12 MPa, which deduces the immersion corrosion resistance of Al coating. The corrosion mechanism of arc sprayed Al coating is pitting corrosion and crevice corrosion, while that by LR is uniform corrosion and pitting corrosion. The corrosion potential of arc sprayed Al coating by LR shifts positively, which improves its immersion corrosion resistance.
Metal roof corrosion related to volcanic ash deposition
NASA Astrophysics Data System (ADS)
Oze, C.; Cole, J. W.; Scott, A.; Wilson, T.; Wilson, G.; Gaw, S.; Hampton, S.; Doyle, C.; Li, Z.
2013-12-01
Volcanoes produce a wide range of hazards capable of leading to increased rates of corrosion to the built environment. Specifically, widely distributed volcanic ash derived from explosive volcanic eruptions creates both short- and long-term hazards to infrastructure including increased corrosion to exposed building materials such as metal roofing. Corrosion has been attributed to volcanic ash in several studies, but these studies are observational and are beset by limitations such as not accounting for pre-existing corrosion damage and/or other factors that may have also directly contributed to corrosion. Here, we evaluate the corrosive effects of volcanic ash, specifically focusing on the role of ash leachates, on a variety of metal roofing materials via weathering chamber experiments. Weathering chamber tests were carried out for up to 30 days using a synthetic ash dosed with an acidic solution to produce a leachate comparable to a real volcanic ash. Visual, chemical and surface analyses did not definitively identify significant corrosion in any of the test roofing metal samples. These experiments attempted to provide quantitative information with regards to the rates of corrosion of different types of metal roof materials. However, they demonstrate that no significant corrosion was macroscopically or microscopically present on any of the roofing surfaces despite the presence of corrosive salts after a duration of thirty days. These results suggest ash leachate-related corrosion is not a major or immediate concern in the short-term (< 1 month).
Wastewater-Enhanced Microbial Corrosion of Concrete Sewers.
Jiang, Guangming; Zhou, Mi; Chiu, Tsz Ho; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L
2016-08-02
Microbial corrosion of concrete in sewers is known to be caused by hydrogen sulfide, although the role of wastewater in regulating the corrosion processes is poorly understood. Flooding and splashing of wastewater in sewers periodically inoculates the concrete surface in sewer pipes. No study has systematically investigated the impacts of wastewater inoculation on the corrosion of concrete in sewers. This study investigated the development of the microbial community, sulfide uptake activity, and the change of the concrete properties for coupons subjected to periodic wastewater inoculation. The concrete coupons were exposed to different levels of hydrogen sulfide under well-controlled conditions in laboratory-scale corrosion chambers simulating real sewers. It was evident that the periodic inoculation induced higher corrosion losses of the concrete in comparison to noninoculated coupons. Instantaneous measurements such as surface pH did not reflect the cumulative corrosion losses caused by long-term microbial activity. Analysis of the long-term profiles of the sulfide uptake rate using a Gompertz model supported the enhanced corrosion activity and greater corrosion loss. The enhanced corrosion rate was due to the higher sulfide uptake rates induced by wastewater inoculation, although the increasing trend of sulfide uptake rates was slower with wastewater. Increased diversity in the corrosion-layer microbial communities was detected when the corrosion rates were higher. This coincided with the environmental conditions of increased levels of gaseous H2S and the concrete type.
46 CFR 197.320 - Diving ladder and stage.
Code of Federal Regulations, 2011 CFR
2011-10-01
... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...
46 CFR 197.320 - Diving ladder and stage.
Code of Federal Regulations, 2010 CFR
2010-10-01
... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...
46 CFR 197.320 - Diving ladder and stage.
Code of Federal Regulations, 2012 CFR
2012-10-01
... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...
46 CFR 197.320 - Diving ladder and stage.
Code of Federal Regulations, 2013 CFR
2013-10-01
... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...
46 CFR 197.320 - Diving ladder and stage.
Code of Federal Regulations, 2014 CFR
2014-10-01
... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...
Maintainability Improvement Through Corrosion Prediction
1997-12-01
Aluminum base alloys - Mechanical properties; Lithium- Alloying elements; Crack propagation- Corrosion effects ; Fatigue life - Corrosion... effects on the corrosion fatigue life of 7075-T6 aluminum alloy . Ma,L CORPORATE SOURCE: University of Utah JOURNAL: Dissertation Abstracts International...Diffusion effects ; Hydrogen- Diffusion SECTION HEADINGS: 64 (Corrosion) 52. 715866 87-640094 The Life Prediction for 2024
Corrosion control is a concern for many drinking water utilities. The Lead and Copper Rule established a regulatory need to maintain a corrosion control program. Other corrosion-related issues such as “red” water resulting from excessive iron corrosion and copper pinhole leaks ...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...
46 CFR 154.412 - Cargo tank corrosion allowance.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 5 2011-10-01 2011-10-01 false Cargo tank corrosion allowance. 154.412 Section 154.412... Containment Systems § 154.412 Cargo tank corrosion allowance. A cargo tank must be designed with a corrosion...) carries a cargo that corrodes the tank material. Note: Corrosion allowance for independent tank type C is...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...
46 CFR 154.412 - Cargo tank corrosion allowance.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo tank corrosion allowance. 154.412 Section 154.412... Containment Systems § 154.412 Cargo tank corrosion allowance. A cargo tank must be designed with a corrosion...) carries a cargo that corrodes the tank material. Note: Corrosion allowance for independent tank type C is...
49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 3 2011-10-01 2011-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...
49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...
49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective coating...
49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 3 2014-10-01 2014-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 3 2012-10-01 2012-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2) Bare...
49 CFR 192.459 - External corrosion control: Examination of buried pipeline when exposed.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 3 2013-10-01 2013-10-01 false External corrosion control: Examination of buried... Requirements for Corrosion Control § 192.459 External corrosion control: Examination of buried pipeline when... portion must be examined for evidence of external corrosion if the pipe is bare, or if the coating is...
NASA Astrophysics Data System (ADS)
Eyu, Gaius Debi; Will, Geoffrey; Dekkers, Willem; MacLeod, Jennifer
2015-12-01
The influence of fluid flow, surface roughness and immersion time on the electrochemical behaviour of carbon steel in coal seam gas produced water under static and hydrodynamic conditions has been studied. The disc electrode surface morphology before and after the corrosion test was characterized using scanning electron microscopy (SEM). The corrosion product was examined using X-ray photoelectron spectroscopy (XPS) and X-ray diffractometry (XRD).The results show that the anodic current density increased with increasing surface roughness and consequently a decrease in corrosion surface resistance. Under dynamic flow conditions, the corrosion rate increased with increasing rotating speed due to the high mass transfer coefficient and formation of non-protective akaganeite β-FeO(OH) and goethite α-FeO(OH) corrosion scale at the electrode surface. The corrosion rate was lowest at 0 rpm. The corrosion rate decreased in both static and dynamic conditions with increasing immersion time. The decrease in corrosion rate is attributed to the deposition of corrosion products on the electrode surface. SEM results revealed that the rougher surface exhibited a great tendency toward pitting corrosion.
Hsieh, Ming-Kai; Li, Heng; Chien, Shih-Hsiang; Monnell, Jason D; Chowdhury, Indranil; Dzombak, David A; Vidic, Radisav D
2010-12-01
Secondary treated municipal wastewater is a promising alternative to fresh water as power plant cooling water system makeup water, especially in arid regions. Laboratory and field testing was conducted in this study to evaluate the corrosiveness of secondary treated municipal wastewater for various metals and metal alloys in cooling systems. Different corrosion control strategies were evaluated based on varied chemical treatment. Orthophosphate, which is abundant in secondary treated municipal wastewater, contributed to more than 80% precipitative removal of phosphorous-based corrosion inhibitors. Tolyltriazole worked effectively to reduce corrosion of copper (greater than 95% inhibition effectiveness). The corrosion rate of mild steel in the presence of free chlorine 1 mg/L (as Cl2) was approximately 50% higher than in the presence of monochloramine 1 mg/L (as Cl2), indicating that monochloramine is a less corrosive biocide than free chlorine. The scaling layers observed on the metal alloys contributed to corrosion inhibition, which could be seen by comparing the mild steel 21-day average corrosion rate with the last 5-day average corrosion rate, the latter being approximately 50% lower than the former.
NASA Technical Reports Server (NTRS)
Russell, Richard W.; Calle, Luz Marina; Johnston, Frederick; Montgomery, Eliza L.; Curran, Jerome P.; Kolody, Mark R.
2013-01-01
NASA began corrosion studies at the Kennedy Space Center (KSC) in 1966 during the Gemini/Apollo Programs with the evaluation of long-term corrosion protective coatings for carbon steel. KSC's Beachside Corrosion Test Site (BCTS), which has been documented by the American Society of Materials (ASM) as one of the most corrosive, naturally occurring, environments in the world, was established at that time. With the introduction of the Space Shuttle in 1981, the already highly corrosive conditions at the launch pad were rendered even more severe by the acid ic exhaust from the solid rocket boosters. In the years that followed, numerous studies have identified materials, coatings, and maintenance procedures for launch hardware and equipment exposed to the highly corrosive environment at the launch pad. This paper presents a historical overview of over 45 years of corrosion and coating evaluation studies and a description of the BCTS's current capabilities. Additionally, current research and testing programs involving chromium free coatings, environmentally friendly corrosion preventative compounds, and alternates to nitric acid passivation will be discussed.