WorldWideScience

Sample records for hull coating system

  1. Estimating hull coating thickness distributions using the EM Algorithm

    OpenAIRE

    Corriere, Michael A.

    2000-01-01

    The underwater hull coating system on surface ships is comprised anti-corrosive (AC) and anti-fouling (AF) paint The AF layers are designed to wear away, continuously leaching cuprous oxide to inhibit marine growth. The thickness of the AF paint layers determines the expected service life of a coating system. Thus, it is important to assess the thickness of the AF layers to determine if the current hull coating system is sufficient. The Naval Ship Technical Manual (NSTM) provides specific gui...

  2. Diatom community structure on commercially available ship hull coatings.

    Science.gov (United States)

    Zargiel, Kelli A; Coogan, Jeffrey S; Swain, Geoffrey W

    2011-10-01

    Diatoms are primary colonizers of both antifouling and fouling-release ship hull coatings. There are few published studies which report on diatom community development on modern ship hull coatings. This study reports diatom communities on eight commercial marine ship hull coatings exposed at three static immersion sites along the east coast of Florida, viz. Daytona, Sebastian, and Miami. The coatings tested were three ablative copper systems (Ameron ABC-3, International BRA-640, and Hempel Olympic 76600), two copper-free biocidal systems (E-Paint SN-1, Sherwin Williams HMF), and three fouling-release (FR) systems (International Intersleek 700, International Intersleek 900, and Hempel Hempasil). One hundred and twenty-seven species comprising 44 genera were identified, including some of the more commonly known foulers, viz. Achnanthes, Amphora, Cocconeis, Entomoneis, Licmophora, Melosira, Navicula, Nitzschia, Synedra, and Toxarium. A significant difference was seen among sites, with the more estuarine site, Sebastian, having lower overall diatom abundance and higher diversity than Daytona and Miami. Copper coatings were primarily fouled by Amphora delicatissima and Entomoneis pseudoduplex. Copper-free coatings were fouled by Cyclophora tenuis, A. delicatissima, Achnanthes manifera, and Amphora bigibba. FR surfaces were typified by C. tenuis, and several species of Amphora. The presence of C. tenuis is new to the biofouling literature, but as new coatings are developed, this diatom may be one of many that prove to be problematic for static immersion. Results show coatings can be significantly influenced by geographical area, highlighting the need to test ship hull coatings in locations similar to where they will be utilized.

  3. Brush development for underwater ship hull coating maintenance

    Science.gov (United States)

    Tribou, Melissa Eileen

    Ship hull grooming has been proposed as an environmentally friendly method of maintaining ship hull coatings in a fouling-free condition. It is defined as the frequent and gentle cleaning of a ship hull coating to prevent the establishment of fouling. This research investigated the grooming tool properties and operational requirements needed to implement the method. The grooming tool needs to provide sufficient force to remove incipient fouling without damaging the surface and consume minimal energy. Research showed that a vertical rotating brush design containing brushes filled with angled polypropylene bristles provided an effective method. This brush system was able to successfully prevent incipient fouling from becoming established on a copper ablative and two silicone fouling release coatings when groomed on a weekly basis; however, biofilm was not completely controlled. Brush design and operational parameters in relation to brush normal forces were investigated and models were developed to understand the relationship between bristle stiffness, dimensions, and angular velocity. A preliminary look at wear found that bristle stiffness has an effect on the degree of marring of the surface of a silicone fouling release coating. The knowledge gained by this research may be used to optimize grooming brush design and operational parameters that can be applied to the design and deployment of low power autonomous underwater vehicles that will groom the ship while in port.

  4. In-Water Hull Cleaning & Filtration System

    Science.gov (United States)

    George, Dan

    2015-04-01

    Dan George R & D Mining Technology LinkedIn GRD Franmarine have received the following prestigious awards in 2014 for their research & development of an in-water hull cleaning and filtration system "The Envirocart: Golden Gecko Award for Environmental Excellence; WA Innovator of the Year - Growth Sector; Department of Fisheries - Excellence in Marine Biosecurity Award - Innovation Category; Lloyd's List Asia Awards - Environmental Award; The Australian Innovation Challenge - Environment, Agriculture and Food Category; and Australian Shipping and Maritime Industry Award - Environmental Transport Award. The Envirocart developed and patented by GRD Franmarine is a revolutionary new fully enclosed capture and containment in-water hull cleaning technology. The Envirocart enables soft Silicon based antifouling paints and coatings containing pesticides such as Copper Oxide to be cleaned in situ using a contactless cleaning method. This fully containerised system is now capable of being deployed to remote locations or directly onto a Dive Support Vessel and is rated to offshore specifications. This is the only known method of in-water hull cleaning that complies with the Department of Agriculture Fisheries and Forestry (DAFF) and Department of Fisheries WA (DoF) Guidelines. The primary underwater cleaning tool is a hydraulically powered hull cleaning unit fitted with rotating discs. The discs can be fitted with conventional brushes for glass or epoxy based coatings or a revolutionary new patented blade system which can remove marine biofouling without damaging the antifouling paint (silicone and copper oxide). Additionally there are a patented range of fully enclosed hand cleaning tools for difficult to access niche areas such as anodes and sea chests, providing an innovative total solution that enables in-water cleaning to be conducted in a manner that causes no biological risk to the environment. In full containment mode or when AIS are present, material is pumped

  5. A New Anticorrosive Coating System For Navy Ship Hulls%新型舰船船体防腐蚀涂料配套体系的研究

    Institute of Scientific and Technical Information of China (English)

    金晓鸿; 洪栋煌

    2001-01-01

    The research of a new anticorrosive coating system fo r navy ship hulls is described. The coating system consists of the anticorrosive primer (fast drying water-based inorganic silicate zinc coating or organic zin c-rich coating ), the barrier type tie coating and the special optical finishing. The system is screened out by a series of tests including traditional performance test, acce lerated test, the system compatibility test, the simulated-panel test exposed to the sea and the ship application test. The results indicate that th e system is superior to that of the existing system in protective performances a nd is complied with the new navy requirements in optical properties.%介绍了一种新型舰船船体用防腐蚀涂料配套体系.这种涂料体系是由防锈底漆(水溶性快速固化无机硅酸锌底漆或有机富锌底漆)、具有屏蔽功能的中间层涂料和具有特种光学性能的面漆组成的.通过实验室的常规性能试验、加速暴露试验和配套性试验对研制的防锈底漆、中间层涂料和面漆配套体系进行了筛选,并对筛选出的体系进行了实海环境暴露试验、模拟体实海浸泡试验以及实艇涂装应用试验.试验结果表明,该防腐蚀涂料体系在防腐蚀性能方面明显优于目前使用的涂料体系,符合海军对舰艇艇体特种光学性能的最新要求.

  6. 46 CFR 154.178 - Contiguous hull structure: Heating system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous hull structure: Heating system. 154.178... Equipment Hull Structure § 154.178 Contiguous hull structure: Heating system. The heating system for... the heating capacity to meet § 154.174(b)(2) or § 154.176(b)(2); (b) Have stand-by heating to...

  7. Effects of biofouling development on drag forces of hull coatings for ocean-going ships: a review

    DEFF Research Database (Denmark)

    Lindholdt, Asger; Dam-Johansen, Kim; Olsen, S. M.;

    2015-01-01

    This review presents a systematic overview of the literature and describes the experimental methods used to quantify the drag of hull coatings. It also summarizes the findings of hull coating's drag performance and identifies the main parameters impacting it. The advantages and disadvantages...... of the reported methods listed in this review provide an assessment of the most efficient methods to quantify the drag performance of hull coatings. This review determines that drag performance of hull coating technology varies depending on whether the coating condition is newly applied, after dynamic or static...

  8. Determination of efficiency of anechoic or decoupling hull coatings using water tank acoustic measurements

    OpenAIRE

    AUDOLY, Christian

    2012-01-01

    International audience; External anechoic and decoupling hull coatings are used on ships or submarines to reduce acoustic target strength and radiated noise, respectively. Measurement of test panels in a water tank gives only the reflection and transmission coefficients in free field, with respects to frequency. It is shown using simple models that anechoic and decoupling efficiencies can be derived, providing appropriate modulus and phase measurement of the coefficients. Additionnally, the i...

  9. A Sensor System for Detection of Hull Surface Defects

    Directory of Open Access Journals (Sweden)

    Juan Suardíaz

    2010-07-01

    Full Text Available This paper presents a sensor system for detecting defects in ship hull surfaces. The sensor was developed to enable a robotic system to perform grit blasting operations on ship hulls. To achieve this, the proposed sensor system captures images with the help of a camera and processes them in real time using a new defect detection method based on thresholding techniques. What makes this method different is its efficiency in the automatic detection of defects from images recorded in variable lighting conditions. The sensor system was tested under real conditions at a Spanish shipyard, with excellent results.

  10. Drag resistance measurements for newly applied antifouling coatings and welding seams on ship hull surface

    DEFF Research Database (Denmark)

    Wang, Xueting; Olsen, S. M.; Andres, E.

    in their newly applied conditions. The effects of water absorption of newly applied antifouling coatings on frictional resistance were measured. A flexible rotor with artificial welding seams on its periphery has been designed and constructed to estimate the influence of welding seams on drag resistance. Both......Drag resistances of newly applied antifouling coatings and welding seams on ship hull surface have been investigated using a pilot-scale rotary setup. Both conventional biocide-based antifouling (AF) coatings and silicone-based fouling release (FR) coatings have been studied and compared...... the density of welding seams (number per 5 m ship side) and the height of welding seams had a significant effect on drag resistance....

  11. Static vs dynamic settlement and adhesion of diatoms to ship hull coatings.

    Science.gov (United States)

    Zargiel, Kelli A; Swain, Geoffrey W

    2014-01-01

    Many experiments utilize static immersion tests to evaluate the performance of ship hull coatings. These provide valuable data; however, they do not accurately represent the conditions both the hull and fouling organisms encounter while a ship is underway. This study investigated the effect of static and dynamic immersion on the adhesion and settlement of diatoms to one antifouling coating (BRA 640), four fouling-release coatings (Intersleek(®) 700, Intersleek(®) 900, Hempasil X3, and Dow Corning 3140) and one standard surface (Intergard(®) 240 Epoxy). Differences in community composition were observed between the static and dynamic treatments. Achnanthes longipes was present on all coatings under static immersion, but was not present under dynamic immersion. This was also found for diatoms in the genera Bacillaria and Gyrosigma. Melosira moniformis was the only diatom present under dynamic conditions, but not static conditions. Several common fouling diatom genera were present on panels regardless of treatment: Amphora, Cocconeis, Entomoneis Cylindrotheca, Licmophora, Navicula, Nitzschia, Plagiotropis, and Synedra. Biofilm adhesion, diatom abundance and diatom diversity were found to be significantly different between static and dynamic treatments; however, the difference was dependent on coating and sampling date. Several coatings (Epoxy, DC 3140 and IS 700) had significantly higher biofilm adhesion on dynamically treated panels on at least one of the four sampling dates, while all coatings had significantly higher diatom abundance on at least one sampling date. Diversity was significantly greater on static panels than dynamic panels for Epoxy, IS 700 and HX3 at least once during the sampling period. The results demonstrate how hydrodynamic stress will significantly influence the microfouling community. Dynamic immersion testing is required to fully understand how antifouling surfaces will respond to biofilm formation when subjected to the stresses experienced

  12. Validation of Closed Loop Degaussing System for Double Hull Submarines

    OpenAIRE

    Demilier, Laurent; Cauffet, Gilles; Chadebec, Olivier; Coulomb, Jean-Louis; Rouve, Laure-Line

    2010-01-01

    International audience; This paper presents last DCNS development on Closed Loop Degaussing System dedicated to high performance electromagnetic silent warship. This paper focuses on an evolution of the CLDG algorithm for degaussed warship. Developed in cooperation with Grenoble Electrical Engineering Lab, this genuine method allows to determine the hull unknown magnetization components, thus the predicted signature, based on real time magnetic measurements from sensors located very close to ...

  13. Data on photo-nanofiller models for self-cleaning foul release coating of ship hulls.

    Science.gov (United States)

    Selim, Mohamed S; El-Safty, Sherif A; El-Sockary, Maher A; Hashem, Ahmed I; Abo Elenien, Ossama M; El-Saeed, Ashraf M; Fatthallah, Nesreen A

    2016-09-01

    The data presented in this article are related to the research article entitled "Smart photo-induced silicone/TiO2 nanocomposites with dominant [110] exposed surfaces for self-cleaning foul-release coatings of ship hulls" (Selimet al., 2016) [1]. This article reports on successfully designing and controlling TiO2 spherical single crystal photo-nanofillers and indicating evidence of fouling resistance after stimulation through UV radiation exposure. These data also reveal that the influence of well-dispersed spherical TiO2 nanoparticles (NPs) into the polymer matrix surface features on the prepared fouling release (FR) coating. Single crystal TiO2 nanospheres have played a large role in the scenario of photocatalysis due to its cost effectiveness, inert nature and photo stability. The model output and the surface and mechanical behavior data of the fabricated UV-irradiated silicone-based FR nanocoatings are made publicly available through analyzing nanocomposite topology, superhydrophilicity and self-cleaning efficiency in order to enable critical analysis of the tailored model. It also investigates the photo-bactericidal effect confirmed through biofilm coverage data disability. The modeled nanocomposites were subjected to comparable studies with other published models so as to understand how different UV-irradiated nano-scale parameters propagate and affect bulk film response.

  14. Diatom community structure on in-service cruise ship hulls.

    Science.gov (United States)

    Hunsucker, Kelli Zargiel; Koka, Abhishek; Lund, Geir; Swain, Geoffrey

    2014-10-01

    Diatoms are an important component of marine biofilms found on ship hulls. However, there are only a few published studies that describe the presence and abundance of diatoms on ships, and none that relate to modern ship hull coatings. This study investigated the diatom community structure on two in-service cruise ships with the same cruise cycles, one coated with an antifouling (AF) system (copper self-polishing copolymer) and the other coated with a silicone fouling-release (FR) system. Biofilm samples were collected during dry docking from representative areas of the ship and these provided information on the horizontal and vertical zonation of the hull, and intact and damaged coating and niche areas. Diatoms from the genera Achnanthes, Amphora and Navicula were the most common, regardless of horizontal ship zonation and coating type. Other genera were abundant, but their presence was more dependent on the ship zonation and coating type. Samples collected from damaged areas of the hull coating had a similar community composition to undamaged areas, but with higher diatom abundance. Diatom fouling on the niche areas differed from that of the surrounding ship hull and paralleled previous studies that investigated differences in diatom community structure on static and dynamically exposed coatings; niche areas were similar to static immersion and the hull to dynamic immersion. Additionally, diatom richness was greater on the ship with the FR coating, including the identification of several new genera to the biofouling literature, viz. Lampriscus and Thalassiophysa. These results are the first to describe diatom community composition on in-service ship hulls coated with a FR system. This class of coatings appears to have a larger diatom community compared to copper-based AF systems, with new diatom genera that have the ability to stick to ship hulls and withstand hydrodynamic forces, thus creating the potential for new problematic species in the biofilm.

  15. Geographic Information Systems (GIS)-based assessment of rice hull energy resource in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Capareda, S.C. [University of the Philippines at Los Banos, Laguna (Philippines)

    1999-07-01

    Geographic Information System (GIS) was used as a tool in encoding available rice hull production data in the Philippines to determine the exact location of rice hull resources, the potential electrical power that could be generated given a certain radius of coverage, and the trend in yearly production. Data from the Bureau of Agricultural Statistics (1997), the National Statistics Office (1994), and the National Food Authority (1997) were used to calculate and validate available rice hull resources. Maps from the National Mapping and Resource Wonnation Administration (1997) were digitized and the available rice hull resource was estimated for each municipality in the top producing regions. In 1996, an estimated 2.3 million metric tons of rice hull produced over a wide geographic range with an energy equivalent of about 970 MW. Central Luzon, Western Visayas and the Cagayan Valley are the regions with the largest rice hull resource. There is sufficient rice hull resource in the Philippines to merit the development of technologies for thermal energy production. (author)

  16. Assessing 3-D Uncertain System Stability by Using MATLAB Convex Hull Functions

    OpenAIRE

    Mohammed Tawfik Hussein

    2011-01-01

    This paper is dealing with the robust stability of an uncertain three dimensional (3-D) system using existence MATLAB convex hull functions. Hence, the uncertain model of plant will be simulated by INTLAB Toolbox; furthermore, the root loci of the characteristic polynomials of the convex hull are obtained to judge whether the uncertain system is stable or not. A design third order example for uncertain parameters is given to validate the proposed approach.

  17. MULTI-AGENT COMPUTER AIDED ASSEMBLY PROCESS PLANNING SYSTEM FOR SHIP HULL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A multi-agent computer aided assembly process planning system (MCAAPP) for ship hull is presented. The system includes system framework, global facilitator, the macro agent structure, agent communication language, agent-oriented programming language, knowledge representation and reasoning strategy. The system can produce the technological file and technological quota, which can satisfy the production needs of factory.

  18. Research and development of a digital design system for hull structures

    Science.gov (United States)

    Zhan, Yi-Ting; Ji, Zhuo-Shang; Liu, Yin-Dong

    2007-06-01

    Methods used for digital ship design were studied and formed the basis of a proposed frame model suitable for ship construction modeling. Based on 3-D modeling software, a digital design system for hull structures was developed. Basic software systems for modeling, modifying, and assembly simulation were developed. The system has good compatibility, and models created by it can be saved in different 3-D file formats, and 2D engineering drawings can be output directly. The model can be modified dynamically, overcoming the necessity of repeated modifications during hull structural design. Through operations such as model construction, intervention inspection, and collision detection, problems can be identified and modified during the hull structural design stage. Technologies for centralized control of the system, database management, and 3-D digital design are integrated into this digital model in the preliminary design stage of shipbuilding.

  19. Research and development of a digital design system for hull structures

    Institute of Scientific and Technical Information of China (English)

    ZHAN Yi-ting; JI Zhuo-shang; LIU Yin-dong

    2007-01-01

    Methods used for digital ship design were studied and formed the basis of a proposed frame model suitable for ship construction modeling. Based on 3-D modeling software, a digital design system for hull structures was developed. Basic software systems for modeling, modifying, and assembly simulation were developed. The system has good compatibility, and models created by it can be saved indifferent 3-D file formats, and 2D engineering drawings can be output directly. The model can be modified dynamically, overcoming the necessity of repeated modifications during hull structural design.Through operations such as model construction, intervention inspection, and collision detection,problems can be identified and modified during the hull structural design stage. Technologies for centralized control of the system, database management, and 3-D digital design are integrated into this digital model in the preliminary design stage of shipbuilding.

  20. Comparative Performance of High Efficiency Ship Propulsion Systems for Destroyer Hull Types. Volume I

    Science.gov (United States)

    1974-12-06

    i pi» ■«■■i . ilMi<MI««iPMpM«l««P«nMVHV*W«nPW- AD-A007 340 COMPARATIVE PERFORMANCE OF HIGH EFFICIENCY SHIP PROPULSION SYSTEMS...OF HIGH EFFICIENCY SHIP PROPULSION SYSTEMS FOR DESTROYER HULL TYPES VOLUME I By Alan J. Stewart 6 December 1974 Approved for Public Release... Ship Propulsion Systems for Destroyer Hull Types 7. AH r:i.iR(JJ Alan J. Stewart 9. Pr.fii-OFIMING OiiüANIi ATION NAMI A’JD AOOMESS Bradford

  1. The Effect of Hull Biofouling on Parameters Characterising Ship Propulsion System Efficiency

    Directory of Open Access Journals (Sweden)

    Tarełko Wiesła

    2015-01-01

    Full Text Available One of most important issues concerning technical objects is the increase of their operating performance. For a ship this performance mainly depends on the efficiency of its main pro-pulsion system and the resistance generated during its motion on water. The overall ship re-sistance, in turn, mainly depends on the hull friction resistance, closely related with the pres-ence of different types of roughness on the hull surface, including underwater part biofouling. The article analyses the effect of hull biofouling on selected parameters characterising the efficiency of the ship propulsion system with adjustable propeller. For this purpose a two-year research experiment was performed on a sailing vessel during its motor navigation phases. Based on the obtained results, three groups of characteristics were worked out for different combinations of engine rotational speed and adjustable propeller pitch settings. The obtained results have revealed that the phenomenon of underwater hull biofouling affects remarkably the parameters characterising propulsion system efficiency. In particular, the development of the biofouling layer leads to significant reduction of the speed of navigation.

  2. Optimization of compartments arrangement of submarine pressure hull with knowledge based system

    Science.gov (United States)

    Chung, Bo-Young; Kim, Soo-Young; Shin, Sung-Chul; Koo, Youn-Hoe; Kraus, Andreas

    2011-12-01

    This study aims to optimize an arrangement of ship compartments with knowledge-based systems. Though great attention has been shown to the optimization of hull forms in recent years, the study on arrangement design optimization has received relatively little attention. A ship is both an engineering system and a kind of assembly of many spaces. This means that, to design an arrangement of ship compartments, it is necessary to treat not only geometric data but also knowledge on topological relations between spaces and components of a ship. In this regard, we select a suitable knowledge representation scheme for describing ship compartments and their relations, and then develop a knowledge-based system using expert system shell. This new approach is applied to create design variations for optimization on an arrangement of a pressure hull of a submerged vehicle. Finally, we explicate how our approach improves the design process.

  3. Calculation of the hull and of the car-suspension systems of airships

    Science.gov (United States)

    Verduzio, R

    1924-01-01

    Differential and integral curves are presented and well as numerous calculations relating to hulls. Some of the calculations include those relating to hulls, those relating to the invariability of the shape of the hulls, and those relating to the suspension of the hull.

  4. Advanced thermal barrier coating systems

    Science.gov (United States)

    Dorfman, M. R.; Reardon, J. D.

    1985-01-01

    Current state-of-the-art thermal barrier coating (TBC) systems consist of partially stabilized zirconia coatings plasma sprayed over a MCrAlY bond coat. Although these systems have excellent thermal shock properties, they have shown themselves to be deficient for a number of diesel and aircraft applications. Two ternary ceramic plasma coatings are discussed with respect to their possible use in TBC systems. Zirconia-ceria-yttria (ZCY) coatings were developed with low thermal conductivities, good thermal shock resistance and improved resistance to vanadium containing environments, when compared to the baseline yttria stabilized zirconia (YSZ) coatings. In addition, dense zirconia-titania-yttria (ZTY) coatings were developed with particle erosion resistance exceeding conventional stabilized zirconia coatings. Both coatings were evaluated in conjunction with a NiCr-Al-Co-Y2O3 bond coat. Also, multilayer or hybrid coatings consisting of the bond coat with subsequent coatings of zirconia-ceria-yttria and zirconia-titania-yttria were evaluated. These coatings combine the enhanced performance characteristics of ZCY with the improved erosion resistance of ZTY coatings. Improvement in the erosion resistance of the TBC system should result in a more consistent delta T gradient during service. Economically, this may also translate into increased component life simply because the coating lasts longer.

  5. Coefficients of Propeller-hull Interaction in Propulsion System of Inland Waterway Vessels with Stern Tunnels

    Directory of Open Access Journals (Sweden)

    Jan Kulczyk

    2014-09-01

    Full Text Available Propeller-hull interaction coefficients - the wake fraction and the thrust deduction factor - play significant role in design of propulsion system of a ship. In the case of inland waterway vessels the reliable method of predicting these coefficients in early design stage is missing. Based on the outcomes from model tests and from numerical computations the present authors show that it is difficult to determine uniquely the trends in change of wake fraction and thrust deduction factor resulting from the changes of hull form or operating conditions. Nowadays the resistance and propulsion model tests of inland waterway vessels are carried out rarely because of relatively high costs. On the other hand, the degree of development of computational methods enables’ to estimate the reliable values o interaction coefficients. The computations referred to in the present paper were carried out using the authors’ own software HPSDKS and the commercial software Ansys Fluent.

  6. Data on photo-nanofiller models for self-cleaning foul release coating of ship hulls

    Directory of Open Access Journals (Sweden)

    Mohamed S. Selim

    2016-09-01

    Full Text Available The data presented in this article are related to the research article entitled “Smart photo-induced silicone/TiO2 nanocomposites with dominant [110] exposed surfaces for self-cleaning foul-release coatings of ship hulls” (Selimet al., 2016 [1]. This article reports on successfully designing and controlling TiO2 spherical single crystal photo-nanofillers and indicating evidence of fouling resistance after stimulation through UV radiation exposure. These data also reveal that the influence of well-dispersed spherical TiO2 nanoparticles (NPs into the polymer matrix surface features on the prepared fouling release (FR coating. Single crystal TiO2 nanospheres have played a large role in the scenario of photocatalysis due to its cost effectiveness, inert nature and photo stability. The model output and the surface and mechanical behavior data of the fabricated UV-irradiated silicone-based FR nanocoatings are made publicly available through analyzing nanocomposite topology, superhydrophilicity and self-cleaning efficiency in order to enable critical analysis of the tailored model. It also investigates the photo-bactericidal effect confirmed through biofilm coverage data disability. The modeled nanocomposites were subjected to comparable studies with other published models so as to understand how different UV-irradiated nano-scale parameters propagate and affect bulk film response.

  7. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  8. A fast adaptive convex hull algorithm on two-dimensional processor arrays with a reconfigurable BUS system

    Science.gov (United States)

    Olariu, S.; Schwing, J.; Zhang, J.

    1991-01-01

    A bus system that can change dynamically to suit computational needs is referred to as reconfigurable. We present a fast adaptive convex hull algorithm on a two-dimensional processor array with a reconfigurable bus system (2-D PARBS, for short). Specifically, we show that computing the convex hull of a planar set of n points taken O(log n/log m) time on a 2-D PARBS of size mn x n with 3 less than or equal to m less than or equal to n. Our result implies that the convex hull of n points in the plane can be computed in O(1) time in a 2-D PARBS of size n(exp 1.5) x n.

  9. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  10. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  11. INNOVATIVE COATING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Asamatdinov Marat Orynbaevich

    2017-03-01

    Full Text Available Restoration of monuments of architecture is a sphere of activity which places particularly high demands on technical specialists and experts. It is necessary, depending on the objectives of restoration and finishing of a monument of architecture and its damages and defects, to select appropriate technologies and materials. Mineral substances as fillers, and inorganic (mineral colouring pigments, along with liquid potassium glass form an ultrastrong combination of materials. It gives to paints made of these mineral substances, an extremely high weather resistance and durability.The functional concept of silicate paints is the ability to silicify with other mineral construction materials. Silicate paints are the only colouring system which enters into chemical compound with the base due to the liquid potassium silicate properties. Also, bonds between quartzitic elements in its fillers are formed. As a result, it provides yet greater wear resistance and resistance to chalking. In ICA MGSU bachelors-technologists are given the "Facade Materials in the Modern Architecture of Buildings” course, in which special attention is paid to decorative coatings of various types; also, scientific research for improvement of paintwork material application technologies is performed. Cooperation of the higher school entities with technical assistance centres of construction firms makes it possible to enhance the quality of training and competence of graduates, as well as create favorable conditions for development of modern domestic technologies including those in the sphere of execution of architectural facades using innovative systems.

  12. Stochastic Dynamic Programming Applied to Hydrothermal Power Systems Operation Planning Based on the Convex Hull Algorithm

    Directory of Open Access Journals (Sweden)

    Bruno H. Dias

    2010-01-01

    Full Text Available This paper presents a new approach for the expected cost-to-go functions modeling used in the stochastic dynamic programming (SDP algorithm. The SDP technique is applied to the long-term operation planning of electrical power systems. Using state space discretization, the Convex Hull algorithm is used for constructing a series of hyperplanes that composes a convex set. These planes represent a piecewise linear approximation for the expected cost-to-go functions. The mean operational costs for using the proposed methodology were compared with those from the deterministic dual dynamic problem in a case study, considering a single inflow scenario. This sensitivity analysis shows the convergence of both methods and is used to determine the minimum discretization level. Additionally, the applicability of the proposed methodology for two hydroplants in a cascade is demonstrated. With proper adaptations, this work can be extended to a complete hydrothermal system.

  13. A markerless motion capture system to study musculoskeletal biomechanics: visual hull and simulated annealing approach.

    Science.gov (United States)

    Corazza, S; Mündermann, L; Chaudhari, A M; Demattio, T; Cobelli, C; Andriacchi, T P

    2006-06-01

    Human motion capture is frequently used to study musculoskeletal biomechanics and clinical problems, as well as to provide realistic animation for the entertainment industry. The most popular technique for human motion capture uses markers placed on the skin, despite some important drawbacks including the impediment to the motion by the presence of skin markers and relative movement between the skin where the markers are placed and the underlying bone. The latter makes it difficult to estimate the motion of the underlying bone, which is the variable of interest for biomechanical and clinical applications. A model-based markerless motion capture system is presented in this study, which does not require the placement of any markers on the subject's body. The described method is based on visual hull reconstruction and an a priori model of the subject. A custom version of adapted fast simulated annealing has been developed to match the model to the visual hull. The tracking capability and a quantitative validation of the method were evaluated in a virtual environment for a complete gait cycle. The obtained mean errors, for an entire gait cycle, for knee and hip flexion are respectively 1.5 degrees (+/-3.9 degrees ) and 2.0 degrees (+/-3.0 degrees ), while for knee and hip adduction they are respectively 2.0 degrees (+/-2.3 degrees ) and 1.1 degrees (+/-1.7 degrees ). Results for the ankle and shoulder joints are also presented. Experimental results captured in a gait laboratory with a real subject are also shown to demonstrate the effectiveness and potential of the presented method in a clinical environment.

  14. Anticorrosion Performance of Epoxy Coatings Containing Small Amount of Inherently Conducting PEDOT/PSS on Hull Steel in Seawater

    Institute of Scientific and Technical Information of China (English)

    Jian Hou; Guang Zhu; Jingkun Xu; Huajian Liu

    2013-01-01

    Corrosion protection of the hull steel by the conventional epoxy paint containing a small amount of commercial poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT/PSS),which is one of the most popular and successful inherently conducting polymers as the corrosion inhibitor was studied.The corrosion behavior of the samples was investigated in seawater by electrochemical impedance spectroscopy and open circuit potential.Scanning electron microscopy was used to observe the surface morphology of the samples after corrosion.It was found that adding a small amount of PEDOT/PSS to the epoxy resin can significantly improve its corrosion protection.

  15. Modern approaches to marine antifouling coatings

    OpenAIRE

    Chambers, Lily D.; Stokes, Keith R.; Walsh, Frank C.; Wood, Robert J.K.

    2006-01-01

    Marine structures such as platforms, jetties and ship hulls are subject to diverse and severe biofouling. Methods for inhibiting both organic and inorganic growth on wetted substrates are varied but most antifouling systems take the form of protective coatings. Biofouling can negatively affect the hydrodynamics of a hull by increasing the required propulsive power and the fuel consumption. This paper reviews the development of antifouling coatings for the prevention of marine biological fouli...

  16. Effect of corrosion on the ship hull of a double hull very large crude oil carrier

    Science.gov (United States)

    Vu Van, Tuyen; Yang, Ping

    2017-09-01

    This study aims to examine and analyze the effect of corrosion wastage on the ship hull of a double hull very large crude oil carrier. To calculate the ultimate bending moment capacity, along with the neutral axis position at the limit state, section modulus, and moment of inertia, the incremental-iterative method is employed. This paper also considered the residual strength checking criteria of ship hull and the ultimate stress behaviors of the representative structural elements. Then, Paik's probabilistic corrosion, which employs two levels of corrosion rate and three different assumptions of coating life time, is applied to assess the corrosion effects. The calculation results obtained through relevant analyses are also presented.

  17. Diffusion Barrier Coating System and Oxidation Behavior of Coated Alloys

    Institute of Scientific and Technical Information of China (English)

    T.NARITA

    2009-01-01

    @@ 1 Introduction Research into the formation of Re-based alloys is in progress in our laboratory to provide a diffusion barrier layer between heat-resistant alloys and Al reservoir layers, which assist in the formation and maintenance a protective Al2O3 scale for long periods. Coatings with a two-layered structure comprised of inner Re-based alloy layer and outer β-NiAl layer with or without Pt addition were successfully formed on various heat resistant alloys such as Ni-based singlecrystal superalloys, Ni-based heat resistant alloys, NiMo based alloy, Ni-Cr based alloy, and Fe-based alloys. The duplex layer coating proposed is generally termed a diffusion barrier coating system; DBC system.

  18. 46 CFR 154.516 - Piping: Hull protection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping: Hull protection. 154.516 Section 154.516... and Process Piping Systems § 154.516 Piping: Hull protection. A vessel's hull must be protected from...-522), at: (a) Each piping connection dismantled on a routine basis; (b) Cargo discharge and...

  19. A new approach to hull consistency

    Directory of Open Access Journals (Sweden)

    Kolev Lubomir

    2016-06-01

    Full Text Available Hull consistency is a known technique to improve the efficiency of iterative interval methods for solving nonlinear systems describing steady-states in various circuits. Presently, hull consistency is checked in a scalar manner, i.e. successively for each equation of the nonlinear system with respect to a single variable. In the present poster, a new more general approach to implementing hull consistency is suggested which consists in treating simultaneously several equations with respect to the same number of variables.

  20. Optics and multilayer coatings for EUVL systems

    Energy Technology Data Exchange (ETDEWEB)

    Soufli, R; Bajt, S; Hudyma, R M; Taylor, J S

    2008-03-21

    EUV lithography (EUVL) employs illumination wavelengths around 13.5 nm, and in many aspects it is considered an extension of optical lithography, which is used for the high-volume manufacturing (HVM) of today's microprocessors. The EUV wavelength of illumination dictates the use of reflective optical elements (mirrors) as opposed to the refractive lenses used in conventional lithographic systems. Thus, EUVL tools are based on all-reflective concepts: they use multilayer (ML) coated optics for their illumination and projection systems, and they have a ML-coated reflective mask.

  1. Dynamic Planar Convex Hull

    DEFF Research Database (Denmark)

    Jacob, Riko

    We determine the computational complexity of the dynamic convex hull problem in the planar case. We present a data structure that maintains a finite set of n points in the plane under insertion and deletion of points in amortized O(log n) time per operation. The space usage of the data structure...... is O(n). The data structure supports extreme point queries in a given direction, tangent queries through a given point, and queries for the neighboring points on the convex hull in O(log n) time. The extreme point queries can be used to decide whether or not a given line intersects the convex hull......, and the tangent queries to determine whether a given point is inside the convex hull. The space usage of the data structure is O(n). We give a lower bound on the amortized asymptotic time complexity that matches the performance of this data structure....

  2. Dynamic Planar Convex Hull

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølfting; Jacob, Rico

    2002-01-01

    In this paper we determine the computational complexity of the dynamic convex hull problem in the planar case. We present a data structure that maintains a finite set of n points in the plane under insertion and deletion of points in amortized O(log n) time per operation. The space usage...... of the data structure is O(n). The data structure supports extreme point queries in a given direction, tangent queries through a given point, and queries for the neighboring points on the convex hull in O(log n) time. The extreme point queries can be used to decide whether or not a given line intersects...... the convex hull, and the tangent queries to determine whether a given point is inside the convex hull. We give a lower bound on the amortized asymptotic time complexity that matches the performance of this data structure....

  3. Thermal barrier coating for alloy systems

    Science.gov (United States)

    Seals, Roland D.; White, Rickey L.; Dinwiddie, Ralph B.

    2000-01-01

    An alloy substrate is protected by a thermal barrier coating formed from a layer of metallic bond coat and a top coat formed from generally hollow ceramic particles dispersed in a matrix bonded to the bond coat.

  4. ETV Program Report: Coatings for Wastewater Collection Systems - Standard Cement Materials, Epoxy Coating 4553

    Science.gov (United States)

    The Standard Cement Materials, Inc. Standard Epoxy Coating 4553™ (SEC 4553) epoxy coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Ma...

  5. ETV Program Report: Coatings for Wastewater Collection Systems - Standard Cement Materials, Epoxy Coating 4553

    Science.gov (United States)

    The Standard Cement Materials, Inc. Standard Epoxy Coating 4553™ (SEC 4553) epoxy coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Ma...

  6. Article Including Environmental Barrier Coating System

    Science.gov (United States)

    Lee, Kang N. (Inventor)

    2015-01-01

    An enhanced environmental barrier coating for a silicon containing substrate. The enhanced barrier coating may include a bond coat doped with at least one of an alkali metal oxide and an alkali earth metal oxide. The enhanced barrier coating may include a composite mullite bond coat including BSAS and another distinct second phase oxide applied over said surface.

  7. Matching Forces Applied in Underwater Hull Cleaning with Adhesion Strength of Marine Organisms

    Directory of Open Access Journals (Sweden)

    Dinis Oliveira

    2016-10-01

    Full Text Available Biofouling is detrimental to the hydrodynamic performance of ships. In spite of advances in hull coating technology, a ship must usually undergo underwater hull cleaning to remove biofouling during her in-service time. However, some cleaning practices may also lead to decreased lifetime of the fouling-control coating. Therefore, cleaning forces should be minimized, according to the adhesion strength of marine organisms present on the hull. In this article, values of adhesion strength found in available literature are discussed in the light of current knowledge on hull cleaning technology. Finally, the following knowledge gaps are identified: (1 data on adhesion strength of naturally-occurring biofouling communities are practically absent; (2 shear forces imparted by current cleaning devices on low-form fouling (microfouling and corresponding effects on hull coatings are largely unknown. This knowledge would be valuable for both developers and users of cleaning technology.

  8. A Study on Corrosion Resistance of Coating System on Steel

    Energy Technology Data Exchange (ETDEWEB)

    Nah, Hwan Seon; Lee, Hyeon Ju; Kim, Kang Seok [Korea Electricity Power Research Institute, Daejeon (Korea, Republic of); Lee, Chul Woo [KEPCO E and Co., Yongin (Korea, Republic of)

    2007-04-15

    The design purpose of architectural finish on steel structures is to prevent corrosion in the respect of structural durability, function, beauty and economy. In particular, as structures located on shores is easily degraded due to damage from salt, it is necessary to evaluate the applied coating systems on steel structures. This study is focused on anti-corrosive tests of both steel surfaces and high strength bolts. Two kinds of tests were conducted on each specimen under the condition of outdoor exposure and salt spray comparatively during 760 hours. In case of coating systems on steel surfaces, three layered coating system showed the best function among the various coating systems. Regarding the coating systems on high strength bolts, the coating system composed of zinc dust on hot dip galvanized coating was found to be the best against corrosion.

  9. Overlay metallic-cermet alloy coating systems

    Science.gov (United States)

    Gedwill, M. A.; Levine, S. R.; Glasgow, T. K. (Inventor)

    1984-01-01

    A substrate, such as a turbine blade, vane, or the like, which is subjected to high temperature use is coated with a base coating of an oxide dispersed, metallic alloy (cermet). A top coating of an oxidation, hot corrosion, erosion resistant alloy of nickel, cobalt, or iron is then deposited on the base coating. A heat treatment is used to improve the bonding. The base coating serves as an inhibitor to interdiffusion between the protective top coating and the substrate. Otherwise, the protective top coating would rapidly interact detrimentally with the substrate and degrade by spalling of the protective oxides formed on the outer surface at elevated temperatures.

  10. Thermal and Environmental Barrier Coatings for Advanced Propulsion Engine Systems

    Science.gov (United States)

    Zhu, Dong-Ming; Miller, Robert A.

    2004-01-01

    Ceramic thermal and environmental barrier coatings (TEBCs) are used in gas turbine engines to protect engine hot-section components in the harsh combustion environments, and extend component lifetimes. For future high performance engines, the development of advanced ceramic barrier coating systems will allow these coatings to be used to simultaneously increase engine operating temperature and reduce cooling requirements, thereby leading to significant improvements in engine power density and efficiency. In order to meet future engine performance and reliability requirements, the coating systems must be designed with increased high temperature stability, lower thermal conductivity, and improved thermal stress and erosion resistance. In this paper, ceramic coating design and testing considerations will be described for high temperature and high-heat-flux engine applications in hot corrosion and oxidation, erosion, and combustion water vapor environments. Further coating performance and life improvements will be expected by utilizing advanced coating architecture design, composition optimization, and improved processing techniques, in conjunction with modeling and design tools.

  11. 14 CFR 27.755 - Hulls.

    Science.gov (United States)

    2010-01-01

    ... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 27.755 Hulls. For each rotorcraft, with a hull and auxiliary floats, that is to be approved for both taking off from and landing...

  12. Degradation and Failure Characteristics of NPP Containment Protective Coating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, R.L.

    2001-02-22

    A research program to investigate the performance and potential for debris formation of Service Level I coating systems used in nuclear power plant containment is being performed at the Savannah River Technology Center. The research activities are aligned to address phenomena important to cause coating disbondment as identified by the Industry Coatings Expert Panel. The period of interest for performance covers the time from application of the coating through 40 years of service, followed by a medium-to-large break loss-of-coolant accident scenario, which is a design basis accident (DBA) scenario. The interactive program elements are described in this report and the application of these elements to evaluate the performance of the specific coating system of Phenoline 305 epoxy-phenolic topcoat over Carbozinc 11 primer on a steel substrate. This system is one of the predominant coating systems present on steel substrates in NPP containment.

  13. HULLED WHEAT FARMING IN DEVELI

    Directory of Open Access Journals (Sweden)

    Sancar Bulut

    2016-07-01

    Full Text Available Emmer (Triticum dicoccum and einkorn (T. monococcum cultivation has a long history in Anatolia. The crops, cultivated in Anatolia over thousands years, can still be found in some parts of the country, especially Develi in the Kayseri province. The total cultivation area of these crops was around 36 000 ha in 2015. The species is mainly cultivated in sloping and marginal lands by poor farmers, where no other crops can be economically grown. Cultivation area is rapidly declining, and if such trend continues, hulled wheats will be shortly completely wiped out from Turkey. Present-day distribution of emmer and spelt within Turkey is concentrated in countryside areas of Develi where traditional farming systems still survive. This group of wheats is called in Turkish the general name of ‘kaplìca’ which means ‘covered’ or ‘hulled’. More specifically, the tetraploid species (emmer is called ‘gacer’ in the Develi. Being a low-yielding type of wheat, emmer was replaced by other improved varieties of Triticum. This decrease was mainly due to the widespread use of improved cultivars of wheat and the adoption of new agricultural techniques, but also to social and economic factors. In fact, wheat yielded 2840 t/ha, whereas hulled wheats yielded 1200 t/ha. The cultivation of these two crops shows disadvantages that relate to the harvesting techniques used and the need to dehisce the spikelets to obtain the grain for human consumption. The increasing interest in low-input systems due to the actual ecological and economical situation has led to a growing interest in specific genetic variability. Organic agriculture and health food products have been gaining increasing popularity that has led to a renewed interest in hulled wheat species such as emmer and spelt. The objective of this study was to estimate agronomical and grain quality characteristics of some Turkey (Develi emmer landraces. This effort was motivated by the fact that autochthonous

  14. The Local Transformation of the Catamaran-stern Hull

    Institute of Scientific and Technical Information of China (English)

    XU Na

    2016-01-01

    [Abstract]Lines plan of a ship related to resistance,structural strength,and economic benefit,is a complicated system engineering.Especially for the catamaran-stern hull,the designers have to modify the lines plan of the ship,in order to combine the catamaran-stern with the main ship hull.This paper use trigonometric function method to achieve the local transformation of catamaran-stern hull;on the other hand,making it programmed can effectively shorten the cycle of shipbuilding.

  15. Characterizations of boundary pluripolar hulls

    NARCIS (Netherlands)

    Djire, I.K.; Wiegerinck, J.

    2016-01-01

    We present some basic properties of the so-called boundary relative extremal function and discuss boundary pluripolar sets and boundary pluripolar hulls. We show that for B-regular domains the boundary pluripolar hull is always trivial on the boundary of the domain and present a “boundary version” o

  16. Characterizations of boundary pluripolar hulls

    NARCIS (Netherlands)

    Djire, I.K.; Wiegerinck, J.

    2016-01-01

    We present some basic properties of the so-called boundary relative extremal function and discuss boundary pluripolar sets and boundary pluripolar hulls. We show that for B-regular domains the boundary pluripolar hull is always trivial on the boundary of the domain and present a “boundary version” o

  17. Applications of coatings in coal-fired energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.

    1992-03-01

    Corrosion and erosion of metallic structural materials at elevated temperatures in complex multicomponent gas environments that include particulates are potential problems in many fossil energy systems, especially those using coal as a feedstock. The use of appropriate corrosion-resistant coatings on metallic components offers an avenue to minimize material degradation and extend component life. The purpose of this paper is to review the current status of coating performance in environments typical of pulverized-coal-fired boilers, coal gasification, fluidized-bed combustion, and gas turbines. The paper discusses the complexity of environments in different systems and the coating requirements for acceptable performance. Examples illustrate the morphology and corrosion/erosion performance of coating/structural alloy combinations exposed in some of these systems. La addition, future research and development needs are discussed for coating applications in several coal-fired systems.

  18. Process engineering of ceramic composite coatings for fuel cell systems

    Energy Technology Data Exchange (ETDEWEB)

    Li, G.; Kim, H.; Chen, M.; Yang, Q.; Troczynski, T. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Metals and Materials Engineering

    2003-07-01

    Researchers at UBCeram at the Department of Metals and Materials Engineering at the University of British Columbia have developed a technology to chemically bond composite sol-gel (CB-CSG) coating onto metallic surfaces of complex or concave shapes. The process has been optimized for electrically resistive coatings and corrosion-resistant coatings. The CSG is sprayed onto metallic surfaces and is heat-treated at 300 degrees C to partially dehydrate the hydroxides. The CSG film is then chemically bonded through reaction of active alumina with metal phosphates, such as aluminium phosphate. A new chromate-free process is being developed to address the issue of coatings porosity. The electrodeposition technique involves polymer particles mixed with suspended fine alumina particles which are co-deposited by electrophoretic means or by electrocoagulation. The composite e-coatings have excellent mechanical properties and are being considered as a protective coating for various components of fuel cell systems. 9 refs., 7 figs.

  19. On Fuzzy Simplex and Fuzzy Convex Hull

    Institute of Scientific and Technical Information of China (English)

    Dong QIU; Wei Quan ZHANG

    2011-01-01

    In this paper,we discuss fuzzy simplex and fuzzy convex hull,and give several representation theorems for fuzzy simplex and fuzzy convex hull.In addition,by giving a new characterization theorem of fuzzy convex hull,we improve some known results about fuzzy convex hull.

  20. Active control of radiated pressure of a submarine hull

    Science.gov (United States)

    Pan, Xia; Tso, Yan; Juniper, Ross

    2008-03-01

    A theoretical analysis of the active control of low-frequency radiated pressure from submarine hulls is presented. Two typical hull models are examined in this paper. Each model consists of a water-loaded cylindrical shell with a hemispherical shell at one end and conical shell at the other end, which forms a simple model of a submarine hull. The conical end is excited by an axial force to simulate propeller excitations while the other end is free. The control action is implemented through a Tee-sectioned circumferential stiffener driven by pairs of PZT stack actuators. These actuators are located under the flange of the stiffener and driven out of phase to produce a control moment. A number of cost functions for minimizing the radiated pressure are examined. In general, it was found that the control system was capable of reducing more than half of the total radiated pressure from each of the submarine hull for the first three axial modes.

  1. Pegasus International, Inc. coating removal systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    The Pegasus Coating Removal System (PCRS) was demonstrated at Florida International University (FIU) where it was being evaluated for efficiency and cost. In conjunction with the FIU testing demonstration, a human factors assessment was conducted to assess the hazards and associated safety and health issues of concern for workers utilizing this technology. The PCRS is a chemical paste that is applied to the surface using a brush, roller, or airless sprayer. After the type of PCRS, thickness, and dwell time have been determined, a laminated backed material is placed on top of the chemical paste to slow down the drying process and to provide a mechanism to strip-off the chemical. After the dwell time is reached, the chemical substrate can be removed. Scrapers may be used to break-loose the layers as necessary or to break-loose the layers that are not removed when the laminated paper is picked up. Residue may also be cleaned off of the surface with a damp sponge with an agitating motion, absorbent sponges, or a vacuum, as needed. The paint and removal agent is then placed in drums for disposal at a later time. During the assessment sampling was conducted for organic vapors and general observational techniques were conducted for ergonomics. Recommendations for improved worker safety and health during application and removal of the PCRS include: (1) work practices that reflect avoidance of exposure or reducing the risk of exposure; (2) assuring all PPE and equipment are compatible with the chemicals being used; (3) work practices that reduce the worker`s need to walk on the slippery surface caused by the chemical or the use of special anti-slip soles; (4) careful control of overspray (if a spray application is used); and (5) the use of ergonomically designed long-handled tools to apply and remove the chemical (to alleviate some of the ergonomic concerns).

  2. Degradation and failure characteristics of NPP containment protective coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, R.L.

    2000-03-30

    A research program to investigate the performance and potential for failure of Service Level 1 coating systems used in nuclear power plant containment is in progress. The research activities are aligned to address phenomena important to cause failure as identified by the industry coatings expert panel. The period of interest for performance covers the time from application of the coating through 40 years of service, followed by a medium-to-large break loss-of-coolant accident scenario, which is a design basis accident (DBA) scenario. The interactive program elements are discussed in this report and the application of these elements to the System 5 coating system (polyamide epoxy primer, carbon steel substrate) is used to evaluate performance.

  3. Engineering Hydrodynamic AUV Hulls

    Science.gov (United States)

    Allen, J.

    2016-12-01

    AUV stands for autonomous underwater vehicle. AUVs are used in oceanography and are similar to gliders. MBARIs AUVs as well as other AUVs map the ocean floor which is very important. They also measure physical characteristics of the water, such as temperature and salinity. My science fair project for 4th grade was a STEM activity in which I built and tested 3 different AUV bodies. I wanted to find out which design was the most hydrodynamic. I tested three different lengths of AUV hulls to see which AUV would glide the farthest. The first was 6 inches. The second was 12 inches and the third was 18 inches. I used clay for the nosecone and cut a ruler into two and made it the fin. Each AUV used the same nosecone and fin. I tested all three designs in a pool. I used biomimicry to create my hypothesis. When I was researching I found that long slim animals swim fastest. So, my hypothesis is the longer AUV will glide farthest. In the end I was right. The longer AUV did glide the farthest.

  4. Physicochemical characterization and failure analysis of military coating systems

    Science.gov (United States)

    Keene, Lionel Thomas

    Modern military coating systems, as fielded by all branches of the U.S. military, generally consist of a diverse array of organic and inorganic components that can complicate their physicochemical analysis. These coating systems consist of VOC-solvent/waterborne automotive grade polyurethane matrix containing a variety of inorganic pigments and flattening agents. The research presented here was designed to overcome the practical difficulties regarding the study of such systems through the combined application of several cross-disciplinary techniques, including vibrational spectroscopy, electron microscopy, microtomy, ultra-fast laser ablation and optical interferometry. The goal of this research has been to determine the degree and spatial progression of weathering-induced alteration of military coating systems as a whole, as well as to determine the failure modes involved, and characterizing the impact of these failures on the physical barrier performance of the coatings. Transmission-mode Fourier Transform Infrared (FTIR) spectroscopy has been applied to cross-sections of both baseline and artificially weathered samples to elucidate weathering-induced spatial gradients to the baseline chemistry of the coatings. A large discrepancy in physical durability (as indicated by the spatial progression of these gradients) has been found between older and newer generation coatings. Data will be shown implicating silica fillers (previously considered inert) as the probable cause for this behavioral divergence. A case study is presented wherein the application of the aforementioned FTIR technique fails to predict the durability of the coating system as a whole. The exploitation of the ultra-fast optical phenomenon of femtosecond (10-15S) laser ablation is studied as a potential tool to facilitate spectroscopic depth profiling of composite materials. Finally, the interferometric technique of Phase Shifting was evaluated as a potential high-sensitivity technique applied to the

  5. DIFFUSION COATINGS FOR CORROSION RESISTANT COMPONENTS IN COAL GASIFICATION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Angel Sanjurjo

    2005-01-01

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low cost alloy may improve is resistance to such sulfidation attack and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this reporting period we coated coupons of selected alloy steels with diffusion coatings of Cr and Al, as well as with titanium and tantalum nitrides. The coated samples were analyzed for their surface composition. In several instances, the samples were also cut to determine the depth profile of the coating. Several of the early runs did not yield uniform or deep enough coatings and hence a significant portion of the effort in this period was devoted fixing the problems with our fluidized bed reactor. Before the end of the quarter we had prepared a number of samples, many of them in duplicates, and sent one set to Wabash River Energy Laboratory for them to install in their gasifier. The gasifier was undergoing a scheduled maintenance and thus presented an opportunity to place some of our coupons in the stream of an operating gasifier. The samples submitted included coated and uncoated pairs of different alloys.

  6. Entirely polytetrafluoroethylene coating for pacemaker system contact dermatitis.

    Science.gov (United States)

    Tamenishi, Akinori; Usui, Akihiko; Oshima, Hideki; Ueda, Yuichi

    2008-04-01

    A 63-year-old man underwent pacemaker implantation for complete atrio-ventricular block. The patient repeated admissions for skin necrosis, and generator or pacemaker system was re-implanted each time. The patient was admitted with skin necrosis of the generator pocket three years after re-implantation. A skin patch test was positive on almost all components of the pacemaker system. The patient underwent pacemaker system removal and re-implantation of polytetrafluoroethylene (PTFE) sheets coating pericardium leads and generator. There has been no recurrence. PTFE sheet coating is effective to treat pacemaker system contact dermatitis.

  7. Convex Hulls of Algebraic Sets

    CERN Document Server

    Gouveia, João

    2010-01-01

    This article describes a method to compute successive convex approximations of the convex hull of a set of points in R^n that are the solutions to a system of polynomial equations over the reals. The method relies on sums of squares of polynomials and the dual theory of moment matrices. The main feature of the technique is that all computations are done modulo the ideal generated by the polynomials defining the set to the convexified. This work was motivated by questions raised by Lov\\'asz concerning extensions of the theta body of a graph to arbitrary real algebraic varieties, and hence the relaxations described here are called theta bodies. The convexification process can be seen as an incarnation of Lasserre's hierarchy of convex relaxations of a semialgebraic set in R^n. When the defining ideal is real radical the results become especially nice. We provide several examples of the method and discuss convergence issues. Finite convergence, especially after the first step of the method, can be described expl...

  8. Slurry Coating System Statement of Work and Specification

    Energy Technology Data Exchange (ETDEWEB)

    Chan, S. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-02-06

    The Slurry Coating System will be used to coat crystals with a polymer to support Lawrence Livermore National Security, LLC (LLNS) research and development at Lawrence Livermore National Laboratory (LLNL). The crystals will be suspended in water in a kettle. A polymer solution is added, temperature of the kettle is raised and aggregates of the crystals and polymer form. The slurry is heated under vacuum to drive off the solvents and slowly cooled while mixing to room temperature. The resulting aggregates are then filtered and dried. The performance characteristics and fielding constraints define a unique set of requirements for a new system. This document presents the specifications and requirements for the system.

  9. Effect of feeding corn, hull-less or hulled barley on fermentation by mixed cultures of ruminal microorganisms.

    Science.gov (United States)

    Fellner, V; Burns, J C; Marshall, D S

    2008-05-01

    Increased demands for corn grain warrant the evaluation of alternative grain types for ruminant production systems. This study was conducted to determine the effects of hulled and hull-less barley (Hordeum vulgare L.) cultivars compared with corn (Zea mays L.) as an alternative grain type on fermentation in cultures of mixed ruminal microorganisms. Three continuous fermentors were fed 14 g of dry feed per day (divided equally between 2 feedings) consisting of alfalfa (Medicago sativa L.) hay pellets (40% of dry matter) and 1) ground corn, 2) hulled barley, or 3) hull-less barley concentrate (60% of dry matter) in each fermentor. Following an adaptation period of 5 d, culture samples were taken at 2 h after the morning feeding on d 6, 7, and 8 of each period for analysis. A second run of the fermentors followed the same treatment sequence to provide replication. Culture pH was reduced with corn (5.55) and did not differ between barley cultivars (average pH 5.89). Total volatile fatty acid concentration and acetate to propionate ratio were not different across grain type or barley cultivar with the exception of greater total volatile fatty acid concentrations with hull-less barley. Corn produced less methane (14.6 mmol/d) and ammonia-N (7.3 mg/100 mL) compared with barley (33.1 mmol/d and 22 mg/100 mL, respectively); methane was greater with hull-less barley but ammonia-N concentration was similar between the 2 barley cultivars. Hull-less barley had greater digestibility compared with hulled barley, and corn had reduced digestibility compared with barley. Concentrations of C18:0 were greater and those of C18:1 and C18:2 lesser in cultures fed hulled and hull-less barley compared with corn. Our data indicate that grain type and barley cultivar have an impact on ruminal fermentation. The lesser starch concentration of barley minimized the drop in culture pH and improved digestibility.

  10. 14 CFR 29.755 - Hull buoyancy.

    Science.gov (United States)

    2010-01-01

    ... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.755 Hull buoyancy. Water-based and amphibian rotorcraft. The hull and auxiliary floats, if used, must have enough... stability great enough to minimize the probability of capsizing the rotorcraft for the worst combination...

  11. DIFFUSION COATINGS FOR CORROSION RESISTANT COMPONENTS IN COAL GASIFICATION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Angel Sanjurjo

    2004-05-01

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low cost alloy may improve is resistance to such sulfidation attack and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. A review of the literature indicated that the Fe- and Ni-based high-temperature alloys are susceptible to sulfidation attack unless they are fortified with high levels of Cr, Al, and Si. To impart corrosion resistance, these elements need not be in the bulk of the alloy and need only be present at the surface layers. We selected diffusion coatings of Cr and Al, and surface coatings of Si and Ti for the preliminary testing. These coatings will be applied using the fluidized bed chemical vapor deposition technique developed at SRI which is rapid and relatively inexpensive. We have procured coupons of typical alloys used in a gasifier. These coupons will be coated with Cr, Al, Si, and Ti. The samples will be tested in a bench-scale reactor using simulated coal gas compositions. In addition, we will be sending coated samples for insertion in the gas stream of the coal gasifier.

  12. Hull Girder Fatigue Damage Estimations of a Large Container Vessel by Spectral Analysis

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2013-01-01

    This paper deals with fatigue damage estimation from the analysis of full-scale stress measurements in the hull of a large container vessel (9,400 TEU) covering several months of operation. For onboard decision support and hull monitoring sys-tems, there is a need for a fast reliable method...

  13. DIFFUSION COATINGS FOR CORROSION RESISTANT COMPONENTS IN COAL GASIFICATION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Angel Sanjurjo

    2005-03-01

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low cost alloy may improve is resistance to such sulfidation attack and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this reporting period we conducted two exposure tests with coated and uncoated coupons. The first one was aborted after a short period, because of a leak in the pressure regulator of a CO/CO{sub 2}/H{sub 2} gas mixture gas cylinder that was used to prepare the simulated coal gas stream. Nevertheless, this run was very instructive as it showed that during the brief exposure when the concentration of H{sub 2}S increased to 8.6%, even specialty alloys such as HR160 and I800 were badly corroded, yet the sample of a SS405-steel that was coated with Ti/Ta showed no signs of corrosion. After replacing the pressure regulator, a second run was conducted with a fresh set of coated and uncoated samples. The Ti/Ta-coated on to SS405 steel from the earlier runs was also exposed in this test. The run proceeded smoothly, and at the end of test the uncoated steels were badly damaged, some evidence of corrosion was found on coupons of HR160 and I800 alloys and the Cr-coated steels, but again, the Ti/Ta-coated sample appeared unaffected.

  14. Study on coupling dynamical theory for interaction of propulsion system and hull of large ships:a review%大型船舶推进系统与船体耦合动力学研究综述

    Institute of Scientific and Technical Information of China (English)

    严新平; 李志雄; 刘正林; 杨平; 朱汉华; 杨忠民

    2013-01-01

    This paper reviews theory and methodology that were developed to cope with the matching opti-mization of the ship propulsion system and hull. The recent advancement on the strip theory for the fore-casting of hull deflection under various wave loads, and the impact of the hull deformation on the propulsion shaft line are discussed. The advantages and shortcomings of traditional shafting alignment techniques are reviewed and illustrated through examples. Applications and the state of-the-art in advanced shafting dy-namic alignment are also reviewed. Finally, several main areas for future development in this field are dis-cussed. These include development of the precise modeling theory of the large ship propulsion system un-der uncertainty, the coupled dynamic modeling method for the large ship propulsion system and hull de-flection, and the optimization database for the coupling design of the propulsion system and ship type.%  船舶推进系统-船体的动力学耦合理论是适应船舶大型化发展趋势和提高大型船舶航行性能的理论基础,需要解决大型船舶的大尺度效应、多参数耦合作用以及不确定航行环境与状态对船舶推进系统影响的理论问题,并探索通过改善推进系统的自适应性和工作可靠性来提升船舶航行性能的方法。文章侧重从大型船舶推进系统的状态不确定性分析与评估、水环境—船体—推进系统动力学耦合作用、以及船舶的实验室试验性能与实海环境的航行性能不一致性等三个方面,综合分析了国内外在该领域研究进展,指出尚待解决的问题和今后的研究方向。

  15. Automated Visual Inspection of Ship Hull Surfaces Using the Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Carlos Fernández-Isla

    2013-01-01

    Full Text Available A new online visual inspection technique is proposed, based on a wavelet reconstruction scheme over images obtained from the hull. This type of visual inspection to detect defects in hull surfaces is commonly carried out at shipyards by human inspectors before the hull repair task starts. We propose the use of Shannon entropy for automatic selection of the band for image reconstruction which provides a low decomposition level, thus avoiding excessive degradation of the image, allowing more precise defect segmentation. The proposed method here is capable of on-line assisting to a robotic system to perform grit blasting operations over damage areas of ship hulls. This solution allows a reliable and cost-effective operation for hull grit spot blasting. A prototype of the automated blasting system has been developed and tested in the Spanish NAVANTIA shipyards.

  16. Onboard monitoring of fatigue damage rates in the hull girder

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Dam; Jensen, Jørgen Juncher; Pedersen, Preben Terndrup

    2011-01-01

    Most new advanced ships have extensive data collection systems to be used for continuous monitoring of engine and hull performance, for voyage performance evaluation etc. Such systems could be expanded to include also procedures for stress monitoring and for decision support, where the most...

  17. Mechanical testing of advanced coating system, volume 1

    Science.gov (United States)

    Cruse, T. A.; Nagy, A.; Popelar, C. F.

    1990-01-01

    The Electron Beam Physical Vapor Deposition (EBPVD) coating material has a highly columnar microstructure, and as a result it was expected to have very low tensile strength. To be able to fabricate the required compression and tensile specimens, a substrate was required to provide structural integrity for the specimens. Substrate and coating dimensions were adjusted to provide sufficient sensitivity to resolve the projected loads carried by the EBPVD coating. The use of two distinctively different strain transducer systems, for tension and compression loadings, mandated two vastly different specimen geometries. Compression specimen and tensile specimen geometries are given. Both compression and tensile test setups are described. Data reduction mathematical models are given and discussed in detail as is the interpretation of the results. Creep test data is also given and discussed.

  18. Mechanical degradation of coating systems in high-temperature cyclic oxidation

    CSIR Research Space (South Africa)

    Pennefather, RC

    1995-01-01

    Full Text Available Cyclic oxidation tests were performed on a large variety of commercially available overlay coatings. The results confirmed that the composition of the coating as well as the processing method of the coating can affect the life of the system. Coating...

  19. Economic and Environmental Impact Trade-Offs Related to In-Water Hull Cleanings of Merchant Vessels

    DEFF Research Database (Denmark)

    Pagoropoulos, Aris; Kjær, Louise Laumann; Dong, Yan

    2017-01-01

    Merchant vessels are equipped with antifouling systems to prevent accumulation of marine organisms on the hull—a phenomenon known as fouling. In many cases, however, fouling accumulates and in-water hull cleaning is required. Hull cleanings are part of a hull management scheme, and although...... and avoided costs and environmental impacts from the hull management system, we used both temporally and spatially distributed models to capture the degradation of the antifouling system as well as the global sailing profile of the vessels. Last, we analyzed how each of the modeled impacts varied...

  20. Effect of carbon on microstructure of CrAlCχN1-χ coatings by hybrid coating system

    Institute of Scientific and Technical Information of China (English)

    Sung-Kyu AHN; Se-Hun KWON; Kwang-Ho KIM

    2011-01-01

    A systematic investigation of the microstructure of CrAICχN1-χ coatings as a function of carbon contents was conducted.Quaternary CrAICχN1-χ coatings were deposited on Si wafers by a hybrid coating system combining an arc-ion plating technique and a DC reactive magnetron sputtering technique using Cr and Al targets in the Ar/N2/CH4 gaseous mixture. The effect of carbon content on microstructure of CrAICχN1-χ coatings was investigated with instrumental analyses of X-ray diffraction, X-ray photoelectron, and high-resolution transmission electron microscopy. The results show that the carbon content of CrAICχN1-χ coatings linearly increases with increasing CH4/(CH4/N2) gas flow rate ratio. The surface roughness of the CrAICχN 1-χ coating layer decreases with the increase of carbon content.

  1. High performance coated board inspection system based on commercial components

    CERN Document Server

    Barjaktarovic, M; Radunovic, J

    2007-01-01

    This paper presents a vision system for defect (fault) detection on a coated board developed using three industrial firewire cameras and a PC. Application for image processing and system control was realized with the LabView software package. Software for defect detection is based on a variation of the image segmentation algorithm. Standard steps in image segmentation are modified to match the characteristics of defects. Software optimization was accomplished using SIMD (Single Instruction Multiple Data) technology available in the Intel Pentium 4 processors that provided real time inspection capability. System provides benefits such as: improvement in production process, higher quality of delivered coated board and reduction of waste. This was proven during successful exploitation of the system for more than a year.

  2. Diffusion Coatings for Corrosion Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Angel Sanjurjo

    2005-01-01

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low cost alloy may improve its resistance to such sulfidation attack and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this reporting period we focused on getting a bench-scale test system to expose alloy coupons to simulated gasifier environment. The test facility was designed to allow about 20 specimen coupons to be exposed simultaneously for an extend period to a simulated coal gas stream at temperatures up to 1000 C. The simulated gas stream contained about 26%H{sub 2}, 39%CO, 17%CO{sub 2}, 1.4% H{sub 2}S and balance steam. We successfully ran a 100+h test with coated and uncoated stainless steel coupons. The tested alloys include SS304, SS316, SS405, SS409, SS410, and IN800. The main finding is that Ti/Ta coating provides excellent protection to SS405 under conditions where uncoated austenitic and ferritic stainless steel alloy coupons are badly corroded. Cr coatings also appear to afford some protection against corrosion.

  3. Pentek metal coating removal system: Baseline report; Greenbook (chapter)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-31

    The Pentek coating removal technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The Pentek coating removal system consisted of the ROTO-PEEN Scaler, CORNER-CUTTER{reg_sign}, and VAC-PAC{reg_sign}. They are designed to remove coatings from steel, concrete, brick, and wood. The Scaler uses 3M Roto Peen tungsten carbide cutters while the CORNER-CUTTER{reg_sign} uses solid needles for descaling activities. These hand tools are used with the VAC-PAC{reg_sign} vacuum system to capture dust and debris as removal of the coating takes place. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure minimal, but noise exposure was significant. Further testing for each exposure is recommended because of the environment where the testing demonstration took place. It is feasible that the dust and noise levels will be higher in an enclosed operating environment of different construction. In addition, other areas of concern found were arm-hand vibration, whole-body, ergonomics, heat stress, tripping hazards, electrical hazards, machine guarding, and lockout/tagout.

  4. High removal rate laser-based coating removal system

    Science.gov (United States)

    Matthews, Dennis L.; Celliers, Peter M.; Hackel, Lloyd; Da Silva, Luiz B.; Dane, C. Brent; Mrowka, Stanley

    1999-11-16

    A compact laser system that removes surface coatings (such as paint, dirt, etc.) at a removal rate as high as 1000 ft.sup.2 /hr or more without damaging the surface. A high repetition rate laser with multiple amplification passes propagating through at least one optical amplifier is used, along with a delivery system consisting of a telescoping and articulating tube which also contains an evacuation system for simultaneously sweeping up the debris produced in the process. The amplified beam can be converted to an output beam by passively switching the polarization of at least one amplified beam. The system also has a personal safety system which protects against accidental exposures.

  5. ETV Program Report: Coatings for Wastewater Collection Systems - Protective Liner Systems, Inc., Epoxy Mastic, PLS-614

    Science.gov (United States)

    The Protective Liner Systems International, Inc. Epoxy Mastic PLS-614 coating used for wastewater collection system rehabilitation was evaluated by EPA’s Environmental Technology Verification Program under laboratory conditions at the Center for Innovative Grouting Material and T...

  6. Rotary feeding system for metallic coating installation by electrodeposition

    Science.gov (United States)

    Stănescu, A.; Alecusan, A. M.; Dimitescu, A.

    2016-08-01

    The paper aims to present an alternative feeding system for metallic coatings lines by electrodeposition which lends itself to the circular arrangement of the cuvettes used in such plants. The novelty lies both, in the arrangement of the electrodeposition installation components and mechanical feeding and transport system for parts to be electrodeposited. The control and actuation system of this type of installation simplifies. Nevertheless, all these increase the system reliability and run lower maintenance costs, without adversely affecting the quality of the end product. The paper presents the justification for reducing the total energy consumption in the electrodeposition process, too.

  7. Degradation and Failure Characteristics of NPP Containment Protective Coating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, R.L.

    2001-04-10

    Nuclear power plants (NPPs) must ensure that the emergency core cooling system (ECCS) or safety-related containment spray system (CSS) remains capable of performing its design safety function throughout the life of the plant. This requires ensuring that long-term core cooling can be maintained following a postulated loss-of-coolant accident (LOCA). Adequate safety operation can be impaired if the protective coatings which have been applied to the concrete and steel structures within the primary containment fail, producing transportable debris which could then accumulate on BWR ECCS suction strainers or PWR ECCS sump debris screens located within the containment. This document will present the data collected during the investigation of coating specimens from plants.

  8. 33 CFR 110.31 - Hull Bay and Allerton Harbor at Hull, Mass.

    Science.gov (United States)

    2010-07-01

    ... Hull, Mass. 110.31 Section 110.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Hull, Mass. (a) Area No. 1 in Allerton Harbor. That area north of Hog Island beginning at latitude 42... jurisdiction, and at the discretion, of the local Harbor Master, Hull, Mass....

  9. Process Optimization of a Novel Immediate Release Film Coating System using QbD Principles

    National Research Council Canada - National Science Library

    Teckoe, Jason; Mascaro, Tracey; Farrell, Thomas P; Rajabi-Siahboomi, Ali R

    2013-01-01

    This work describes a quality-by-design (QbD) approach to determine the optimal coating process conditions and robust process operating space for an immediate release aqueous film coating system (Opadry® 200...

  10. Automated system for laser damage testing of coated optics

    Science.gov (United States)

    Ness, Dale C.; Streater, Alan D.

    2005-12-01

    Research Electro-Optics Inc. (REO) has recently developed a new laser damage testing facility for the purpose of optimizing process parameters for fabrication and coating of high-damage optics. It also enables full or sample qualification of optics with laser damage specifications. The fully automated laser damage testing system uses microscope photography for detection of damage and a 3 ns pulse length 1064 nm laser for irradiation of the sample. It can test and statistically analyze damage events from a large number of shots, enabling large area testing for low probability events. The system measures and maps sizes and locations of damage sites down to a few microns in diameter. The results are not subject to variations due to the human operator. For coatings deposited by ion beam sputtering, small defects (less than 20 microns) are found to be most prevalent at the fluences specified for small optics for the National Ignition Facility. The ability to measure and characterize small defects has improved REO's ability to optimize their processes for making coated optics with high damage thresholds. In addition to qualifying particular parts, the periodic testing also assures that equipment and processes remain optimized.

  11. Corrosion Degradation of Coated Aluminum Alloy Systems through Galvanic Interactions

    Science.gov (United States)

    2017-07-19

    chromated  (adhesion  promoting  pretreatment,  praseodymium-­‐rich   primer)  system  in  two   environments ...non-­‐ chromated  coating  system  in  the  two   environments  was   quite  different.  It  should  be  noted  that... chromated  case.  Furthermore,  it  suggests  that  during  prolonged  exposure  to  an  aggressive  

  12. John Hull and the Money Culture

    Science.gov (United States)

    Attfield, David

    2008-01-01

    John Hull's recent educational writings have included several on what he calls the "money culture". This is analysed and criticised in this article. Hull offers a Marxist and a neo-Marxist account of the role of money in western societies utilising the labour theory of value, false consciousness and the materialist interpretation of history. It is…

  13. John Hull and the Money Culture

    Science.gov (United States)

    Attfield, David

    2008-01-01

    John Hull's recent educational writings have included several on what he calls the "money culture". This is analysed and criticised in this article. Hull offers a Marxist and a neo-Marxist account of the role of money in western societies utilising the labour theory of value, false consciousness and the materialist interpretation of history. It is…

  14. Spatially varying microhardness in a platinum-modified nickel aluminide bond coat in a thermal barrier coating system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, M. [Department of Materials Science and Engineering, Case Western Reserve University, 10900 Euclid Avenue White 418, Cleveland, OH 44106-7204 (United States); Heuer, A.H. [Department of Materials Science and Engineering, Case Western Reserve University, 10900 Euclid Avenue White 418, Cleveland, OH 44106-7204 (United States)]. E-mail: heuer@case.edu

    2006-04-15

    hardness of a Pt-modified Ni aluminide bond coat and its ZrO{sub 2} top coat in an electron beam-physical vapor deposition ZrO{sub 2}-based thermal barrier coating system has been studied as a function of temperature in as-deposited and aged (1200 deg. C/1 h) coupon samples, and in a used blade taken out of service after a (modest) fraction of life. A marked brittle to ductile transition at 580 {+-} 30 deg. C was observed in the as-deposited material, in agreement with previous uniaxial tensile data in this system. Significant spatial variation in the hardness of the bond coats were observed at room temperature and could be correlated with spatially varying microstructures.

  15. Coating-Substrate Systems for Thermomechanically Durable Turbine Airfoils

    Science.gov (United States)

    2015-06-30

    the NiAl( Cr , Zr) coating , and EQ coating deposited by NIMS in Tsukuba, Japan, and a vapor phase NiAl aluminide coatings , in comparison to bare Rene...life by about a factor of 2. Relative to the vapor phase aluminide coatings , the oxide- filled cracks in the NiAl( Cr , Zr) coating penetrated through...the coating and interdiffusion zone more rapidly (within 2000 cycles). Additionally, without the constraint of a TBC, the NiAl( Cr , Zr) coating

  16. Formation of hydrotalcite coating on the aluminum alloy 6060 in spray system

    DEFF Research Database (Denmark)

    Zhou, Lingli; Friis, Henrik; Roefzaad, Melanie

    2016-01-01

    Coatings with the composition of Li-Al-NO3 hydrotalcite were formed on the Al alloy 6060 using a spray system. The coatings consist of crystals with a typical hydrotalcite structure. Dense, uniform and blade-like flakes cover completely the surface of the Al substrate. The coatings display a mult...

  17. Influence of boron doping on mechanical and tribological properties in multilayer CVD-diamond coating systems

    Indian Academy of Sciences (India)

    SAJAD HUSSAIN DIN; M A SHAH; N A SHEIKH; K A NAJAR; K RAMASUBRAMANIAN; S BALAJI; M S RAMACHANDRA RAO

    2016-12-01

    Titanium alloy (Ti6Al4V) substrates were deposited with smooth multilayer coatings, by hot filament chemical vapour deposition technique. The effect of boron doping on lattice parameter, residual stresses, hardness and coefficient of friction in multilayer-diamond coating system was studied. The frictional behaviour of the coatings was studied using a ball-on-disc micro-tribometer by sliding the coated samples of titanium alloy (Ti6Al4V) substrates against alumina (Al$_2$O$_3$) balls, and increasing normal load from 1 to 10N. The average friction coefficient decreased from 0.36 to 0.29 for undoped multilayer-diamond coating system and from 0.33 to 0.18 for borondoped (BD) multilayer-diamond coating system. The average indentation depths for undoped and BD multilayerdiamond coating systems were found to be equal to $\\sim$58 and $\\sim$65 nm, respectively, and their hardness values were 60 and 55~GPa, respectively.

  18. Process optimization of a novel immediate release film coating system using QbD principles.

    Science.gov (United States)

    Teckoe, Jason; Mascaro, Tracey; Farrell, Thomas P; Rajabi-Siahboomi, Ali R

    2013-06-01

    This work describes a quality-by-design (QbD) approach to determine the optimal coating process conditions and robust process operating space for an immediate release aqueous film coating system (Opadry® 200). Critical quality attributes (CQAs) or associated performance indicators of the coated tablets were measured while coating process parameters such as percent solids of the coating dispersion, coating spray rate, inlet air temperature, airflow rate and pan speed were varied, using a design of experiment protocol. The optimized process parameters were then confirmed by independent coating trials. Disintegration time of coated tablets was not affected by the coating process conditions used in this study, while tablet appearance, as determined by measurement of tablet color, coating defects and gloss was determined to be a CQA. Tablet gloss increased when low spray rate and low percent solids were used, as well as with increased coating pan speed. The study used QbD principles and experimental design models to provide a basis to identify ranges of coating process conditions which afford acceptable product quality. High productivity, color uniformity, and very low defect levels were obtained with Opadry 200 even when using a broad range of coating process conditions.

  19. 33 CFR 181.29 - Hull identification number display.

    Science.gov (United States)

    2010-07-01

    ... SECURITY (CONTINUED) BOATING SAFETY MANUFACTURER REQUIREMENTS Identification of Boats § 181.29 Hull... boat hull. (a) The primary hull identification number must be affixed— (1) On boats with transoms, to... hull/deck joint, whichever is lowest. (2) On boats without transoms or on boats on which it would be...

  20. 46 CFR 151.10-20 - Hull construction.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Hull construction. 151.10-20 Section 151.10-20 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Barge Hull Construction Requirements § 151.10-20 Hull construction. (a) Construction features. (1) Each barge hull shall be constructed with a suitable bow...

  1. Tungsten carbide coatings with different binders prepared by low power plasma spray system

    Institute of Scientific and Technical Information of China (English)

    GAO Yang; M.F.Morks; FU Ying-qing

    2004-01-01

    Thermal spraying of cermet coatings is widely used for protection of machining parts against wear and corrosion. These coatings consist of WC particles in metal binders such as Co, Cr and Ni. Three kinds of WC powders with different metal binders (Co, NiCr and CoCr) were sprayed by low power plasma spray system on Al-Si-Cu alloy substrate. Fundamental aspects of sprayed cermet coatings, including (i) the effects of binder type on the coating structure, (ii) the hardness and (iii) the microstructure, were investigated. All cermet coatings have the same phase structure such as WC and W2 C. However, the intensities of these phases are different in each coating, mainly due to the difference in solidification rate in each case. Moreover, the hardness measurements are found to be different in each coating. The results show that, binder type has a significant effect on the physical and mechanical properties of the sprayed coatings.

  2. On teh non-destructive inspection system of the coating oil strage tank. Coating tank no hihakai kensa system ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Miyagawa, K. (Nihon University, Tokyo (Japan). Collete of Industrial Technology)

    1991-03-25

    Recently inside bottom steel plates in oil storage tanks are often coated by epoxy resin to prevent corrosion. Since dangerous tanks are obligated to be overhauled regularly by fire protection law, coatings of the tanks are removed when inspected each time and recoated after inspection. To eliminate such waste, a non-destructive inspection system to inspect over coating films without removing them has been demanded. This report examines the non-destructive inspection system on coating films of the tanks and introduces the study on the method to measure corrosion of bottom steel plates by the ultrasonic thickness gage as well as the research on the development of the system and method for non-destructive inspection to detect surface flaw on the weld parts of the bottom plates. Consequently, it was confirmed through experiments that non-destructive inspection on the coating films is possible. 1 ref., 2 tabs.

  3. Oxidation and Hot Corrosion Behavior of a Composite Coating System

    Institute of Scientific and Technical Information of China (English)

    Dongbai XIE; Fuhui WANG

    2003-01-01

    The oxidation and hot corrosion behavior of Co-Ni-Cr-Al-Ta-Y coating produced by magnetron sputtering with and without enamel coating has been investigated in air at 900℃ and in molten 75 wt pct NaCl+25 wt pct Na2SO4at 850℃. The results show that the enamel coating possesses good hot corrosion resistance in the molten salts, in comparison with the sputtered Co-Ni-Cr-Al-Ta-Y coating. In the hot corrosion test, breakaway corrosion did not occur on the samples with enamel coating and the composition of enamel coating did not significantly change either. The oxidation resistance of the sputtered coating, which offers good adhesion, can be improved by the enamel coating.

  4. Global Loads on FRP Ship Hulls

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1997-01-01

    Fibre reinforced plastic (FRP) composites used for high-speed vessels have lower modulus of elasticity than the conventionally used steels.Therefore, for large fast ships the lowest natural frequencies of the global hull modes can be relatively low compared to the frequency of waveencounter....... As part of the NoKoS project it was decided to investigate the effect of hull flexibility on the wave-induced as well as accidental structural loads on high-speed ships.Especially it was decided to determine whether there is an upper size of FRP and aluminium mono-hulls caused by continuous wave action...

  5. Pressure Hull Analysis under Shock Loading

    Directory of Open Access Journals (Sweden)

    Ya-Jung Lee

    2008-01-01

    Full Text Available The hull of high performance submarines must resist underwater shock loading due to exploding torpedoes or depth bombs. An underwater shock involving an initial shock wave and successive bubble pulsating waves is so complex that a theoretical technique for deriving shock pressure distribution is required for improving simulation efficiency. Complete shock loading is obtained theoretically in this work, and responses of a submarine pressure hull are calculated using ABAQUS USA (Underwater Shock Analysis codes. In the long run, this deflection and stress data will assist in examining the structural arrangement of the submarine pressure hull.

  6. Underwater Explosion Damage of Ship Hull Panels

    OpenAIRE

    K. Rarnajeyathilagam; Vendhan, C.P.

    2003-01-01

    Underwater explosion is a major threat to ships and submarines in a war environment. The prediction of the mode and the extent of the failure is an essential step in designing for shock loading. The localised failure in a hull panel is severe compared to the global response of the ship. In this study, an attempt has been made to predict the response and failure modes of three types of hull panels (flat, concave, and convex). The shock loading on the hull panel has been estimated based on the ...

  7. Novel Surface Coating System Based on Maleated Shellac

    OpenAIRE

    Hasmukh S. Patel; Sumeet J. Patel

    2010-01-01

    Shellac a natural forest product was reacted with various proportion of maleic anhydride. The resulted maleated shellac samples were designated as (MS-1 to 3) and applied for the preparation of surface coating material. Thus various compositions of coating materials were prepared by varying the contents of MS and commercial grades of acrylic resins (AR). The coating materials were applied on substrates like plaster of paris, cement and limed surface. All the coating showed film performance wi...

  8. Formation of hydrotalcite coating on the aluminum alloy 6060 in spray system

    DEFF Research Database (Denmark)

    Zhou, Lingli; Friis, Henrik; Roefzaad, Melanie

    2016-01-01

    -layer structure with average thickness of ∼1000 nm. The hydrotalcite-coated samples performed better than those without coatings in salt-spray and filiform-corrosion tests, and further treatment involving sealing with a Mg acetate solution and dipping in a H2O2 + Ce-based solution improved the corrosion......Coatings with the composition of Li-Al-NO3 hydrotalcite were formed on the Al alloy 6060 using a spray system. The coatings consist of crystals with a typical hydrotalcite structure. Dense, uniform and blade-like flakes cover completely the surface of the Al substrate. The coatings display a multi...

  9. Investigations on the Suitability of Coated Steel Piping System for High Pressure Seawater Reverse Osmosis Application

    Science.gov (United States)

    Mobin, Mohammad

    2010-03-01

    This study deals with the investigations concerning with the suitability of coated steel piping system as an economically viable alternative to costly stainless steel piping for high pressure seawater reverse osmosis (SWRO) application. The piping system selected for investigation is a carbon steel piping coated internally and externally with thermoplastic coating (coating powder Plascoat PPA 571). The performance of thermoplastic coating was investigated by conducting SWRO pilot plant test, salt spray test, mechanical tests and testing of the coating under crevices (both in pilot plant and laboratory), and for leachable organics and inorganics (both in laboratory and pilot plant test). The testing of coating in the pilot plant resulted in the formation of some blisters on the internal surface of the pipes. The blisters were broken causing the corrosion of underneath steel. The coating showed a poor resistance to salt fog test. In general, the coating performed satisfactorily under the crevices but showed blistering on either side of the test panels. The adhesive strength of the coating was found to be poor; however, it showed good flexibility. The results of chemical analysis did not show the leaching of organic or inorganic pollutants from the coating.

  10. Pressure Hull Analysis under Shock Loading

    OpenAIRE

    Ya-Jung Lee; Chia-Hao Hsu; Chien-Hua Huang

    2008-01-01

    The hull of high performance submarines must resist underwater shock loading due to exploding torpedoes or depth bombs. An underwater shock involving an initial shock wave and successive bubble pulsating waves is so complex that a theoretical technique for deriving shock pressure distribution is required for improving simulation efficiency. Complete shock loading is obtained theoretically in this work, and responses of a submarine pressure hull are calculated using ABAQUS USA (Underwater Shoc...

  11. Inspecting the inside of underwater hull

    Science.gov (United States)

    Valkovic, Vladivoj; Sudac, Davorin

    2009-05-01

    In order to demonstrate the possibility of identifying the material within ship's underwater hull, sunken ships and other objects on the sea floor tests with the 14 MeV sealed tube neutron generator incorporated inside a small submarine submerged in the test basin filled with sea water have been performed. Results obtained for inspection of diesel fuel and explosive presence behind single and double hull constructions are presented.

  12. Fluorinated ethylene propylene copolymer coating for the stability enhancement of electroactive and photoactive systems

    Science.gov (United States)

    Zhao, Luping; Neoh, K. G.; Zhang, Yan; Kang, E. T.

    2003-11-01

    The effectiveness of radio frequency sputtered fluorinated ethylene propylene copolymer (FEP) for the stability enhancement of electroactive and photoactive systems was investigated. Two kinds of electroactive polymer systems, polyaniline (PANI) coated low density polyethylene (LDPE) film and PANI-viologen assembly, were tested. In both cases, a sputtered FEP coating of coating of 40-50 nm in thickness. The deposition of a FEP coating on the photoactive viologen system (viologen grafted on LDPE film) prolonged its photochromic effect by inhibiting the diffusion of oxygen, and hence the reoxidation of the highly colored viologen radical cations to the dication state.

  13. Residual stresses in coating-based systems, part Ⅰ:Mechanisms and analytical modeling

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiancheng; WU Yixiong; XU Binshi; WANG Haidou

    2007-01-01

    Thin films and multi-layered coatings comprised of different classes of materials are often used for various fimctional devices. The thermo-mechanical integrity of these systems is becoming a major concern and is strongly related to the residual stresses because of the fabrication processes. In this paper, the sources of the residual stresses in the coating-based systems and the concept of"misfit strain" were briefly reviewed. Analytical models were developed to predict the residual stresses in multi-layered film structures or coating-based systems using the force and moment balances. In addition, the residual stress distributions in the functionally and compositionally graded coatings were also analyzed.

  14. The design of underwater hull-cleaning robot

    Institute of Scientific and Technical Information of China (English)

    YUAN Fu-cai; GUO Li-bin; MENG Qing-xin; LIU Fu-qiang

    2004-01-01

    The research on underwater ship-hull cleaning robot was conducted on the purpose of realizing the automation of cleaning underwater ship hull so that service life of ship will be prolonged and ship speed will raised. Moreover, fuel consumption and the work intensity of divers will be reduced. In this paper, the current situation and the latest technology in China and abroad were analyzed;meanwhile, the typical characteristics of the underwater cleaning robot were introduced. According to the work principle of the underwater cleaning robot, the emphasis was put on the analysis and study of permanent-magnetic absorption, magnetic wheel, airproof and anticorrosion, underwater cleaning equipment and control system. The robot is easy in rotation and simple in control.

  15. Ultimate Strength of Ship Hulls under Torsion

    DEFF Research Database (Denmark)

    Paik, Jeom Kee; Thayamballi, Anil K.; Pedersen, Preben Terndrup

    2001-01-01

    For a ship hull with large deck openings such as container vessels and some large bulk carriers, the analysis of warping stresses and hatch opening deformations is an essential part of ship structural analyses. It is thus of importance to better understand the ultimate torsional strength characte......For a ship hull with large deck openings such as container vessels and some large bulk carriers, the analysis of warping stresses and hatch opening deformations is an essential part of ship structural analyses. It is thus of importance to better understand the ultimate torsional strength...... characteristics of ships with large hatch openings. The primary aim of the present study is to investigate the ultimate strength characteristics of ship hulls with large hatch openings under torsion. Axial (warping) as well as shear stresses are normally developed for thin-walled beams with open cross sections...... analyses, it is shown that the influence of torsion induced warping stresses on the ultimate hull girder bending strength is small for ductile hull materials while torsion induced shear stresses will of course reduce the ship hull ultimate bending moment....

  16. DIFFUSION COATINGS FOR CORROSION RESISTANT COMPONENTS IN COAL GASIFICATION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Angel Sanjurjo

    2004-05-01

    Heat-exchangers, filters, turbines, and other components in integrated coal gasification combined cycle system must withstand demanding conditions of high temperatures and pressure differentials. Under the highly sulfiding conditions of the high temperature coal gas, the performance of components degrade significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low cost alloy may improve is resistance to such sulfidation attack and decrease capital and operating costs. A review of the literature indicates that the corrosion reaction is the competition between oxidation and sulfidation reactions. The Fe- and Ni-based high-temperature alloys are susceptible to sulfidation attack unless they are fortified with high levels of Cr, Al, and Si. To impart corrosion resistance, these elements need not be in the bulk of the alloy and need only be present at the surface layers.

  17. DEVELOPMENT OF A NO-VOC/NO-HAP WOOD FURNITURE COATINGS SYSTEM

    Science.gov (United States)

    The report gives results of the development and demonstration of a no-VOC (volatile organic compound)/no-HAP (hazardous air pollutant) wood furniture coating system. The performance characteristics of the new coating system are excellent in terms of adhesion, drying time, gloss, ...

  18. Noah, Joseph and Convex Hulls

    Science.gov (United States)

    Watkins, N. W.; Chau, Y.; Chapman, S. C.

    2010-12-01

    The idea of describing animal movement by mathematical models based on diffusion and Brownian motion has a long heritage. It has thus been natural to account for those aspects of motion that depart from the Brownian by the use of models incorporating long memory & subdiffusion (“the Joseph effect”) and/or heavy tails & superdiffusion (“the Noah effect”). My own interest in this problem was originally from a geoscience perspective, and was triggered by the need to model time series in space physics where both effects coincide. Subsequently I have been involved in animal foraging studies [e.g. Edwards et al, Nature, 2007]. I will describe some recent work [Watkins et al, PRE, 2009] which studies how fixed-timestep and variable-timestep formulations of anomalous diffusion are related in the presence of heavy tails and long range memory (stable processes versus the CTRW). Quantities for which different scaling relations are predicted between the two approaches are of particular interest, to aid testability. I will also present some of work in progress on the convex hull of anomalously diffusing walkers, inspired by its possible relevance to the idea of home range in biology, and by Randon-Furling et al’s recent analytical results in the Brownian case [PRL, 2009].

  19. Residual Stresses in Thermal Barrier Coatings for a Cu-8Cr-4Nb Substrate System

    Science.gov (United States)

    Ghosn, Louis J.; Raj, Sai V.

    2002-01-01

    Analytical calculations were conducted to determine the thermal stresses developed in a coated copper-based alloy, Cu-8%(at.%)Cr-4%Nb (designated as GRCop-84), after plasma spraying and during heat-up in a simulated rocket engine environment. Finite element analyses were conducted for two coating systems consisting of a metallic top coat, a pure copper bond coat and the GRCop-84. The through thickness temperature variations were determined as a function of coating thickness for two metallic coatings, a Ni-17%(wt%)Cr-6%Al-0.5%Y alloy and a Ni-50%(at.%)Al alloy. The residual stresses after low-pressure plasma spraying of the NiCrAlY and NiAl coatings on GRCop-84 substrate were also evaluated. These analyses took into consideration a 50.8 mm copper bond coat and the effects of an interface coating roughness. The through the thickness thermal stresses developed in coated liners were also calculated after 15 minutes of exposure in a rocket environment with and without an interfacial roughness.

  20. Silica Derived from Burned Rice Hulls

    Directory of Open Access Journals (Sweden)

    M.F. de Souza

    2002-10-01

    Full Text Available Three new processes to obtain silica having high specific surface area from burned pre-treated rice hulls are presented and discussed. These procedures allow for the simultaneous recovery of biomass energy and the production of high quality silica at thermoelectric plants, without the risk of using corrosive substances in the burning process. The first method involves treatment of the hull with hot organic acid solutions before burning, the second with boiling water, both using an autoclave at temperatures close to150 °C, while the third method renders the hull fragile by treating it at 250 °C and reducing it to a fine powder before burning. The first two methods result in white amorphous silica that can show 500 m²/g of specific surface area. The third method, which does not remove the alkaline elements from the hull, produces an amorphous gray carbon-free powder whose specific surface area can be as high as 250 m²/g. An investigation of the specific surface area of the prepared silica indicates the alkaline elements are not mixed with silica in the hulls or combined as insoluble compounds. A comparison is made of these processes and the dissolution of silica by sodium hydroxide solutions is discussed.

  1. Evaluation of the Lifetime and Thermal Conductivity of Dysprosia-Stabilized Thermal Barrier Coating Systems

    Science.gov (United States)

    Curry, Nicholas; Markocsan, Nicolaie; Östergren, Lars; Li, Xin-Hai; Dorfman, Mitch

    2013-08-01

    The aim of this study was the further development of dysprosia-stabilized zirconia coatings for gas turbine applications. The target for these coatings was a longer lifetime and higher insulating performance compared to today's industrial standard thermal barrier coating. Two morphologies of ceramic top coat were studied: one using a dual-layer system and the second using a polymer to generate porosity. Evaluations were carried out using a laser flash technique to measure thermal properties. Lifetime testing was conducted using thermo-cyclic fatigue testing. Microstructure was assessed with SEM and Image analysis was used to characterize porosity content. The results show that coatings with an engineered microstructure give performance twice that of the present reference coating.

  2. Thermal and Environmental Barrier Coating Development for Advanced Propulsion Engine Systems

    Science.gov (United States)

    Zhu, Dongming; Miller, Robert A.; Fox, Dennis S.

    2008-01-01

    Ceramic thermal and environmental barrier coatings (TEBCs) are used in gas turbine engines to protect engine hot-section components in the harsh combustion environments, and extend component lifetimes. Advanced TEBCs that have significantly lower thermal conductivity, better thermal stability and higher toughness than current coatings will be beneficial for future low emission and high performance propulsion engine systems. In this paper, ceramic coating design and testing considerations will be described for turbine engine high temperature and high-heat-flux applications. Thermal barrier coatings for metallic turbine airfoils and thermal/environmental barrier coatings for SiC/SiC ceramic matrix composite (CMC) components for future supersonic aircraft propulsion engines will be emphasized. Further coating capability and durability improvements for the engine hot-section component applications can be expected by utilizing advanced modeling and design tools.

  3. Anticorrosion performance of the coating/metal system by electrochemical impedance spectra

    Institute of Scientific and Technical Information of China (English)

    Yinghuai Zhang; Lining Xu; Minxu Lu; Pu Zhang

    2008-01-01

    In order to investigate the anticorrosion performance of the organic coating/metal system, electrochemical impedance spectra (EIS) were measured in the 3.5wt% NaC1 solution, the chemical component and the formation of corrosion products scale were analyzed by laser Raman microspectroscopy, and the pattern of the organic coating/metal system was observed by scanning electron microscopy (SEM). The characteristics and the delamination process of the organic coating/metal system were investigated systematically, and the emphases were on the transportation of the corrosive medium and the changes of the coating/metal interface. The results show that the impedance decreases at the initial immersion, then increases at the middle-immersion, and again decreases at last, which is related to the corrosion products scale. The concentration of Cl-in the coating, which destroys the corrosion products scale, increases with the immersion time.

  4. Underwater Explosion Damage of Ship Hull Panels

    Directory of Open Access Journals (Sweden)

    K. Rarnajeyathilagam

    2003-10-01

    Full Text Available Underwater explosion is a major threat to ships and submarines in a war environment. The prediction of the mode and the extent of the failure is an essential step in designing for shock loading. The localised failure in a hull panel is severe compared to the global response of the ship. In this study, an attempt has been made to predict the response and failure modes of three types of hull panels (flat, concave, and convex. The shock loading on the hull panel has been estimated based on the Taylor's plate theory. The numerical analysis has been carried out using the CSAIGENSA (DYNA3D code that employs nonlinear finite element model.

  5. Development of a Remotely Controlled Testing Platform with Low-drag Air-ventilated Hull

    Institute of Scientific and Technical Information of China (English)

    Konstantin I. Matveev; Nicholaus I. Perry; Alexander W. Mattson; Christopher S. Chaney

    2015-01-01

    This paper addresses the development and testing of a remotely controlled boat platform with an innovative air-ventilated hull. The application of air cavities on the underside of ship hulls is a promising means for reducing hydrodynamic drag and pollutant emissions and increasing marine transportation efficiency. Despite this concept’s potential, design optimization and high-performance operation of novel air-cavity ships remain a challenging problem. Hull construction and sensor instrumentation of the model-scale air-cavity boat is described in the paper. The modular structure of the hull allows for easy modifications, and an electric propulsion unit enables self-propelled operation. The boat is controlled remotely via a radio transmission system. Results of initial tests are reported, including thrust, speed, and airflow rate in several loading conditions. The constructed platform can be used for optimizing air-cavity systems and testing other innovative hull designs. This system can be also developed into a high-performance unmanned boat.

  6. Characteristics of MCrAlY coatings sprayed by high velocity oxygen-fuel spraying system

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Y.; Saitoh, M.; Tamura, M.

    2000-01-01

    High velocity oxygen-fuel (HVOF) spraying system in open air has been established for producing the coatings that are extremely clean and dense. It is thought that the HVOF sprayed MCrAlY (M is Fe, Ni and/or Co) coatings can be applied to provide resistance against oxidation and corrosion to the hot parts of gas turbines. Also, it is well known that the thicker coating can be sprayed in comparison with any other thermal spraying systems due to improved residual stresses. However, thermal and mechanical properties of HVOF coatings have not been clarified. Especially, the characteristics of residual stress, that are the most important property from the view point of production technique, have not been made clear. In this paper, the mechanical properties of HVOF sprayed MCrAlY coatings were measured in both the case of as-sprayed and heat-treated coatings in comparison with a vacuum plasma sprayed MCrAlY coatings. It was confirmed that the mechanical properties of HVOF sprayed MCrAlY coatings could be improved by a diffusion heat treatment to equate the vacuum plasma sprayed MCrAlY coatings. Also, the residual stress characteristics were analyzed using a deflection measurement technique and a X-ray technique. The residual stress of HVOF coating was reduced by the shot-peening effect comparable to that of a plasma spray system in open air. This phenomena could be explained by the reason that the HVOF sprayed MCrAlY coating was built up by poorly melted particles.

  7. Innovative fiber coating systems based on organic modified ceramics

    Science.gov (United States)

    Schuster, Kay; Kobelke, Jens; Rose, Klaus; Helbig, Manfred; Zoheidi, Mohammad; Heinze, Alexander

    2010-02-01

    We describe the application of inorganic organic hybrid materials (ORMOCERs) as optical fiber coatings for use in Fiber Bragg Grating sensors and high power transmission fibers. The materials are UV curable, enable a single layer thickness of about 50 μm and show high a high peak temperature stability >300 °C. Regarding the fiber protection the coatings have been investigated using tensile strength measurements before and after temperature load. Best coatings maintain the high tensile strength of 68 N (125 μm fiber) with a Weibull parameter of 182 after a temperature cycling up to 300 °C. For the first time a low refractive index ORMOCER will be presented showing a numerical aperture of 0.47 at a wavelength of 1000 nm on a pure silica fiber. This corresponds to a refractive index of 1.37. The fiber possesses a fiber loss of 18 dB/km at a wavelength of 1000 nm. The fibers have been coated using a gravity as well as pressure technology. The latter possesses extremely minimized die equipment and is therefore well applicable for small coating amounts. The so called dead volume within the coating die is about 1 ml. The overall dead volume is only influenced by the supply pipe and can be reduced down to 5 ml.

  8. Analytic Disks and the Projective Hull

    OpenAIRE

    Lawson Jr, H. Blaine; Wermer, John

    2008-01-01

    Let X be a complex manifold and c a simple closed curve in X. We address the question: What conditions on c ensure the existence of a 1-dimensional complex subvariety V with boundary c in X. When X = C^n, an answer to this question involves the polynomial hull of gamma. When X = P^n, complex projective space, the projective hull hat{c} of c comes into play. One always has V contained in hat{c}, and for analytic curves they conjecturally coincide. In this paper we establish an approximate anal...

  9. 46 CFR 45.153 - Through-hull piping: General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Through-hull piping: General. 45.153 Section 45.153 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Conditions of Assignment § 45.153 Through-hull piping: General. (a) All through-hull pipes required by...

  10. 46 CFR 308.107 - War risk hull insurance policy.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false War risk hull insurance policy. 308.107 Section 308.107 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Hull and Disbursements Insurance § 308.107 War risk hull insurance policy. Standard Form...

  11. 33 CFR 181.23 - Hull identification numbers required.

    Science.gov (United States)

    2010-07-01

    ... SECURITY (CONTINUED) BOATING SAFETY MANUFACTURER REQUIREMENTS Identification of Boats § 181.23 Hull... identify each boat produced or imported with two hull identification numbers that meet the requirements of... for the purposes of sale, must identify that boat with two hull identification numbers that meet the...

  12. 14 CFR 29.757 - Hull and auxiliary float strength.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and auxiliary float strength. 29.757 Section 29.757 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand...

  13. 46 CFR 154.172 - Contiguous steel hull structure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous steel hull structure. 154.172 Section 154.172... Structure § 154.172 Contiguous steel hull structure. (a) Except as allowed in paragraphs (b) and (c) of this... construction of the contiguous steel hull structure must meet the thickness and steel grade in Table 1 for...

  14. 46 CFR 282.23 - Hull and machinery insurance.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Hull and machinery insurance. 282.23 Section 282.23... COMMERCE OF THE UNITED STATES Calculation of Subsidy Rates § 282.23 Hull and machinery insurance. (a) Subsidy items. The fair and reasonable net premium costs (including stamp taxes) of hull and...

  15. 46 CFR 252.33 - Hull and machinery insurance.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Hull and machinery insurance. 252.33 Section 252.33... Subsidy Rates § 252.33 Hull and machinery insurance. (a) Subsidy items. The fair and reasonable net premium costs (including stamp taxes) of hull and machinery, increased value, excess general...

  16. Silicone coating systems to improve corrosion protection of steel; Silikonbeschichtungssysteme zur Verbesserung des Korrosionsschutzes von Stahl

    Energy Technology Data Exchange (ETDEWEB)

    Kucharczyk, P.; Fachinger, J.; Odoj, R. [Forschungszentrum Juelich GmbH (Germany); Boehnert, R. [Fachhochschule Koeln (Germany)

    2006-06-15

    Due to German policy an interim storage of radioactive waste during additional 30 years is needed. This requires a high standard of storage containers especially in terms of corrosion resistance. Silicon elastomers (polysiloxanes) have favourable physical and chemical properties and seem to be appropriate for either outer or inner coating of storage containers. In this paper corrosion protection of different silicon coating systems has been investigated. The addition-curing polysiloxane RT622 (Wacker Chemie) was used for experiments. This is a low-viscosity material that could be modified by corrosion protecting pigments like zinc powder and micaceous iron ore. The pigment coatings assured better corrosion protection than unmodified silicon covering. Furthermore, the zinc powder caused the most notable improvement of corrosion protection. The best coating system consisted of a zinc paint and a polysiloxane coating. (orig.)

  17. Corrosion and oxidation properties of NiCr coatings sprayed in presence of gas shroud system

    Energy Technology Data Exchange (ETDEWEB)

    Morks, M.F., E-mail: mhanna@swin.edu.au [Industrial Research Institute Swinburne, Swinburne University of Technology, Hawthorn, Melbourne, VIC 3122 (Australia); Berndt, C.C. [Industrial Research Institute Swinburne, Swinburne University of Technology, Hawthorn, Melbourne, VIC 3122 (Australia)

    2010-04-15

    The oxidation of a NiCr bond coat during air plasma spraying was controlled by designing a gas shroud system attached to the plasma torch nozzle. Two nozzles, termed as 'normal' and 'high-speed' nozzles examined the effect of nozzle internal design on the microstructure and phase structure of coatings. X-ray diffraction and SEM morphologies showed that the shroud system reduced the oxidation of NiCr particles during the spray process. Compared with conventional air plasma spraying, the argon gas shroud reduced the coating hardness because the volume fraction of partially melted particles increased. The high-speed nozzle reduced the oxidation and hardness of NiCr coatings due to the increase of partially melted particles in the coatings.

  18. Residual stress depth profiling in complex hard coating systems by X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Klaus, M. [Technische Universitaet Berlin, Institut fuer Werkstoffwissenschaften und-technologien, Sekr. BH 18, Ernst-Reuter-Platz 1, 10587 Berlin (Germany); Genzel, Ch. [Hahn-Meitner-Institut Berlin, Bereich Strukturforschung, Albert-Einstein-Strasse 15, 12489 Berlin (Germany)], E-mail: genzel@hmi.de; Holzschuh, H. [Walter AG, Derendinger Strasse 53, 72072 Tuebingen (Germany)

    2008-12-01

    X-ray residual stress analysis on multilayered coating systems is a quite difficult and demanding procedure. To obtain information on both, the individual sublayers the coating consists of and the interfacial substrate region, it is necessary to apply different methods which are complementary with respect to the accessible information depth. Based on the concept of an 'equivalent thickness' for describing angle-dispersive diffraction in multilayer structures, a method is proposed that allows for the evaluation of steep intra - as well as interlayer stress gradients within the upper sublayers of multilayer coating systems. Furthermore, energy-dispersive diffraction is shown suitable to detect the residual stress distribution in the near interface substrate zone beneath the coatings. The applicability of the approaches introduced here is demonstrated by the example of cemented carbide WC/Co cutting tools being coated by chemical vapor deposition with sequences of Al{sub 2}O{sub 3}/TiCN sublayers.

  19. An Improved Approach to Fracture Toughness Assessment of Brittle Coating on Ductile Substrate Systems under Indentation

    Science.gov (United States)

    Demidova, Natalia V.

    Fracture toughness is an important material property that determines the structural integrity of a component with pre-existing or service-generated flaws. In the present research, an indentation-based method and the associated fracture mechanics model are proposed for fracture toughness assessment of brittle coating/ductile substrate systems. The proposed models consider well-developed radial/median cracks generated under sharp indentation, despite that the crack formation process may have gone through crack initiation and propagation phases. For generality, the geometry of a well-developed crack is assumed to be semi-elliptical in shape. The driving force of the crack is considered to stem from the residual plastic zone expansion under the indenter, as well as the far-field Boussinesq (elastic) stress. Three well-defined configurations are studied. For the first configuration, a crack with a depth of less than 7% of the coating thickness is considered. In this case, the problem is treated as the one for the monolithic material with the coating material properties. For the second configuration, a crack that runs deeper than 7% of the coating thickness but is still within the coating layer is analyzed. In this case, the composite hardness is introduced into the analysis to account for the influence of the substrate material properties; and furthermore, an interface correction factor is proposed to take into account the presence of the coating/substrate interface and its influence on the stress intensity factor of the well-developed elliptical cracks. For the third configuration, a crack penetrating into the substrate is considered. In this case, based on the condition of deformation compatibility across the coating/substrate interface, the bulk modulus for the coating/substrate system is introduced into the analysis. A series of indentation tests are conducted on a WC/10Co/4Cr coating/1080 low carbon steel substrate specimen, which is a brittle coating on a ductile

  20. Summary of Coating Surveys on the Four Air Command Frigates (Zeven Provincien Class) (Onderzoek naar de conditie van de coatingsystemen op vier luchtcommandofregatten (Zeven Provincien Klasse))

    Science.gov (United States)

    2008-03-26

    surface cleanliness Sa 21/2 1 F/C Sigmaguard CSF 85, 300 pim Water ballast tanks Welds and burnt spots blasting to Sa 2V2, Sewage tanks sweeping of...AlphaGen) was used. Table 13: Coating specifications underwater hulls LCF’s Systems LCF1I LCF 2 LCF 3 LCF 4 Blasting to surface cleanliness Sa 21/ x x x X_ 1

  1. RANS simulation of cavitation and hull pressure fluctuation for marine propeller operating behind-hull condition

    Directory of Open Access Journals (Sweden)

    Kwang-Jun Paik

    2013-12-01

    Full Text Available Simulations of cavitation flow and hull pressure fluctuation for a marine propeller operating behind a hull using the unsteady Reynolds-Averaged Navier-Stokes equations (RANS are presented. A full hull body submerged under the free surface is modeled in the computational domain to simulate directly the wake field of the ship at the propeller plane. Simulations are performed in design and ballast draught conditions to study the effect of cavitation number. And two propellers with slightly different geometry are simulated to validate the detectability of the numerical simulation. All simulations are performed using a commercial CFD software FLUENT. Cavitation patterns of the simulations show good agreement with the experimental results carried out in Samsung CAvitation Tunnel (SCAT. The simulation results for the hull pressure fluctuation induced by a propeller are also compared with the experimental results showing good agreement in the tendency and amplitude, especially, for the first blade frequency.

  2. Electrokinetic Properties of Lubricin Antiadhesive Coatings in Microfluidic Systems.

    Science.gov (United States)

    Greene, George W; Duffy, Emer; Shallan, Aliaa; Wuethrich, Alain; Paull, Brett

    2016-02-23

    Lubricin is a glycoprotein found in articular joints which has long been recognized as being an important biological boundary lubricant molecule and, more recently, an impressive antiadhesive that readily self-assembles into a well ordered, polymer brush layer on virtually any substrate. The lubricin molecule possesses an overabundance of anionic charge, a property that is atypical among antiadhesive molecules, that enables its use as a coating for applications involving electrokinetic processes such as electrophoresis and electroosmosis. Coating the surfaces of silica and polymeric microfluidic devices with self-assembled lubricin coatings affords a unique combination of excellent fouling resistance and high charge density that enables notoriously "sticky" biomolecules such as proteins to be used and controlled electrokinetically in the device without complications arising from nonspecific adsorption. Using capillary electrophoresis, we characterized the stability, uniformity, and electrokinetic properties of lubricin coatings applied to silica and PTFE capillaries over a range of run buffer pHs and when exposed to concentrated solutions of protein. In addition, we demonstrate the effectiveness of lubricin as a coating to minimize nonspecific protein adsorption in an electrokinetically controlled polydimethylsiloxane/silica microfluidic device.

  3. Residual stresses in coating-based systems, part Ⅱ: Optimal designing methodologies

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiancheng; WU Yixiong; XU Binshi; WANG Haidou

    2007-01-01

    In this part of the work,different cases are studied to illustrate the implementation of the analytical models that have been developed in Part Ⅰ [Front.Mech.Eng.China,2007,2(1):1-12].Different topics are involved in the optimal design of coating-based systems.Some essential relations among material properties and dimensions of the coating and substrate and the residual stress variations are reflected.For the multilayered coating-based systems,some optimal design methodologies are proposed,such as the decrease in stress discontinuity at the interface between the adjacent layers,the curvature as a function of the coating thickness,the effect of the interlayer on the residual stress redistribution,and so on.For the single-layered coating-based systems,some typical approximations that are often used to predict the residual stresses in the coating-based system or bilayer structure are corrected.A simplified model for predicting the quenching stress in a coating is also developed.

  4. An investigation of enhanced capability thermal barrier coating systems for diesel engine components

    Science.gov (United States)

    Holtzman, R. L.; Layne, J. L.; Schechter, B.

    1984-01-01

    Material systems and processes for the development of effective and durable thermal barriers for heavy duty diesel engines were investigated. Seven coating systems were evaluated for thermal conductivity, erosion resistance, corrosion/oxidation resistance, and thermal shock resistance. An advanced coating system based on plasma sprayed particle yttria stabilized zirconia (PS/HYSZ) was judged superior in these tests. The measured thermal conductivity of the selected coating was 0.893 W/m C at 371 C. The PS/HYSZ coating system was applied to the piston crown, fire deck and valves of a single cylinder low heat rejection diesel engine. The coated engine components were tested for 24 hr at power levels from 0.83 MPa to 1.17 MPa brake mean effective pressure. The component coatings survived the engine tests with a minimum of distress. The measured fire deck temperatures decreased 86 C (155 F) on the intake side and 42 C (75 F) on the exhaust side with the coating applied.

  5. Welding torch trajectory generation for hull joining using autonomous welding mobile robot

    Science.gov (United States)

    Hascoet, J. Y.; Hamilton, K.; Carabin, G.; Rauch, M.; Alonso, M.; Ares, E.

    2012-04-01

    Shipbuilding processes involve highly dangerous manual welding operations. Welding of ship hulls presents a hazardous environment for workers. This paper describes a new robotic system, developed by the SHIPWELD consortium, that moves autonomously on the hull and automatically executes the required welding processes. Specific focus is placed on the trajectory control of such a system and forms the basis for the discussion in this paper. It includes a description of the robotic hardware design as well as some methodology used to establish the torch trajectory control.

  6. Study of Residual Strength Index of Damaged Ship Hulls

    Institute of Scientific and Technical Information of China (English)

    QIEn-rong; CUIWei-cheng; WANZheng-quan; QIUQiang

    2004-01-01

    This paper studies the effect of non-symmetric flood and rigidity loss of damaged ship hulls to external loads. Based on the calculation method of ultimate strength of damaged ship hulls under non-symmetric bending, the effect of collision, grounding and explosion damage on the ultimate strength of ship hull is also analyzed. Then, residual strength index of damaged ship hulls is given based on extreme loads and ultimate strength calculations. The critical sea state of damaged shin hulls is also predicted.

  7. Design of broadband multilayer dichroic coating for a high-efficiency solar energy harvesting system.

    Science.gov (United States)

    Jiachen, Wang; Lee, Sang Bae; Lee, Kwanil

    2015-05-20

    We report on the design and performance of a broadband dichroic coating for a solar energy conversion system. As a spectral beam splitter, the coating facilitates a hybrid system that combines a photovoltaic cell with a thermal collector. When positioned at a 45° angle with respect to incident light, the coating provides high reflectance in the 40-1100 nm and high transmission in the 1200-2000 nm ranges for a photovoltaic cell and a thermal collector, respectively. Numerical simulations show that our design leads to a sharp transition between the reflection and transmission bands, low ripples in both bands, and slight polarization dependence.

  8. "Keisri hull" on viimast korda laval

    Index Scriptorium Estoniae

    2010-01-01

    Neli hooaega Ugala repertuaaris olnud Jaan Krossi romaani põhjal lavastatud draama "Keisri hull" etendub viimast korda 10. veebruaril. Viimane etendus on pühendatud Jaan Krossi 90. sünniaastapäevale, mis on 19. veebruaril. Lavastajad Peeter Tammearu ja Jaak Allik. Peaosas Peeter Tammearu

  9. "Keisri hull" on viimast korda laval

    Index Scriptorium Estoniae

    2010-01-01

    Neli hooaega Ugala repertuaaris olnud Jaan Krossi romaani põhjal lavastatud draama "Keisri hull" etendub viimast korda 10. veebruaril. Viimane etendus on pühendatud Jaan Krossi 90. sünniaastapäevale, mis on 19. veebruaril. Lavastajad Peeter Tammearu ja Jaak Allik. Peaosas Peeter Tammearu

  10. Hull Form Design and Optimization Tool Development

    Science.gov (United States)

    2012-07-01

    Surface Warfare Center Carderock Division NURBS – Non Uniform Rational B-Spline ONR – Office of Naval Research SSF – Steady Ship Flow SWATH – Small...normalized using different hull parameters. Output HulGen has the ability to create a NURBS surface in Rhinoceros, a commercial 3D modeling software

  11. Rhythmical Alchemy: Village Drumming with Arthur Hull.

    Science.gov (United States)

    Hillerson, Gary R.; Hull, Arthur

    As a step toward writing a master's thesis in psychology, the connection between rhythm circles and psychotherapeutic process was explored. Arthur Hull, who experienced and preached about the healing power of rhythm for many years, was interviewed. This article recorded the interview between Arthur and the researcher. The interviewer learned that…

  12. Projective Hulls and Characterizations of Meromorphic Functions

    CERN Document Server

    Anderson, J T; Levenberg, N; Ransford, T J

    2011-01-01

    We give conditions characterizing holomorphic and meromorphic functions in the unit disk of the complex plane in terms of certain weak forms of the maximum principle. Our work is directly inspired by recent results of John Wermer, and by the theory of the projective hull of a compact subset of complex projective space developed by Reese Harvey and Blaine Lawson.

  13. Committee VI.1. Extreme Hull Girder Loading

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2000-01-01

    Committee Mandate. Evaluate and develop direct calculation procedures for extreme wawe loads on ship hull girders. Due consideration shall be given to stochastic and non-linear effects. The procedures shall be assessed by comparison with in-service experiences, model tests and more refined...

  14. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Jordi Perez-Mariano; Angel Sanjurjo

    2007-03-31

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the hightemperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this period, we analyzed several 409 low alloy steel samples after coating them in our fluidized bed reactor and also after exposing them to our corrosion test. We report the following findings: 1. A protective coating was deposited inside a porous 409 steel sample to protect it from sulfidation attack. The coating was based on a combination of Si diffusion layer, Nb interlayer and nitrides of titanium and silicon. 2. Analysis of solid coupons exposed to simulated coal gas at 900 C for 300 h showed that multilayer metal/ceramic coatings provide a better protection than ceramic coatings. 3. Deposition of several ceramic/metal multilayer coatings showed that coatings with niobium and tantalum interlayers have good adhesion. However, coatings with a tungsten interlayer suffered localized delaminating and coatings with Zr interlayers showed poor adhesion. 4. Analysis of solid coupons, coated with the above-mentioned multilayer films, after exposure to simulated coal gas at 900 C for 300 h showed that niobium is the best candidate for interlayer material.

  15. Effects of internal mass distribution and its isolation on the acoustic characteristics of a submerged hull

    Science.gov (United States)

    Peters, Herwig; Kinns, Roger; Kessissoglou, Nicole

    2014-03-01

    The primary aim of machinery isolation in marine vessels is to isolate structural vibration of the onboard machinery from the hull and to reduce far-field radiation of underwater noise. A substantial proportion of the total submarine mass is on flexible mounts that isolate supported masses from the hull at frequencies above the mounting system resonant frequency. This reduces the dynamically effective mass of the hull and affects the signature of the marine vessel due to propeller excitation. A fully coupled finite element/boundary element (FE/BE) model has been developed to investigate the effect of mass distribution and isolation in a submerged hull. The finite element model of the structure includes internal structures to represent the machinery and other flexibly mounted components. Changes in the radiated sound power demonstrate the effect of machinery isolation on the acoustic signature of the submerged hull due to the external propeller forces. Results are also presented to show how the arrangement of flexible mounts for a large internal structure can influence the radiation due to machinery forces.

  16. CNT coated thread micro-electro-mechanical system for finger proprioception sensing

    Science.gov (United States)

    Shafi, A. A.; Wicaksono, D. H. B.

    2017-04-01

    In this paper, we aim to fabricate cotton thread based sensor for proprioceptive application. Cotton threads are utilized as the structural component of flexible sensors. The thread is coated with multi-walled carbon nanotube (MWCNT) dispersion by using facile conventional dipping-drying method. The electrical characterization of the coated thread found that the resistance per meter of the coated thread decreased with increasing the number of dipping. The CNT coated thread sensor works based on piezoresistive theory in which the resistance of the coated thread changes when force is applied. This thread sensor is sewed on glove at the index finger between middle and proximal phalanx parts and the resistance change is measured upon grasping mechanism. The thread based microelectromechanical system (MEMS) enables the flexible sensor to easily fit perfectly on the finger joint and gives reliable response as proprioceptive sensing.

  17. A Mathematical Model for Diffusion-Controlled Monolithic Matrix Coated with outer Membrane System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A release model for diffusion-controlled monolithic matrix coated with outer membrane system is proposed and solved by using the refined double integral method. The calculated results are in satisfactory agreement with the experimental release data. The present model can be well used to describe the release process for all cd/cs values. In addition, the release effects of the monolithic matrix coated with outer membrane system are discussed theoretically.

  18. An Investigation on of Galvanic Corrosion between Exhaust System of Titanium Alloy and Hull Steel%钛合金与钢的电偶腐蚀行为研究

    Institute of Scientific and Technical Information of China (English)

    司卫华

    2013-01-01

    Corrosion and electrochemical characters of titanium alloys TA28 and Ti6321 as well as ship hull steels 907A and 921A,which are employed in ship,were studied by using electrochemical methods.Experiment was carried out to investigate galvanic corrosion behavior between titanium alloys and ship hull steels in different area ratio.Results show that slight galvanic corrosion would occur on ship hull when TA28 or Ti6321 are used,while a proper insolating can effectively control the galvanic corrosion between titanium alloys and ship hull steel.%研究了TA28、Ti6321钛合金以及921A、907A船体结构钢在海水环境中的腐蚀特性及电化学行为,对两种钛合金与船体钢之间多面积比条件下的电偶腐蚀行为进行了试验.结果表明,当钛合金与钢直接接触时,钛合金与钢制船体间存在轻微的电偶腐蚀,采用电绝缘措施可以有效控制钛合金对钢制船体的电偶腐蚀.

  19. Electrochemical nano-coating processes in solar energy systems

    Directory of Open Access Journals (Sweden)

    F. Kadırgan

    2006-01-01

    Full Text Available The efficiencies of electrochemically prepared nano-thick CdS and black nickel coatings were investigated as a function of their preparation conditions in the application field of energy; such as, solar-electricity conversion, solar cells, and solar-thermal conversion, spectrally selective solar collectors.

  20. Structural Health Monitoring of Tall Buildings with Numerical Integrator and Convex-Concave Hull Classification

    Directory of Open Access Journals (Sweden)

    Suresh Thenozhi

    2012-01-01

    Full Text Available An important objective of health monitoring systems for tall buildings is to diagnose the state of the building and to evaluate its possible damage. In this paper, we use our prototype to evaluate our data-mining approach for the fault monitoring. The offset cancellation and high-pass filtering techniques are combined effectively to solve common problems in numerical integration of acceleration signals in real-time applications. The integration accuracy is improved compared with other numerical integrators. Then we introduce a novel method for support vector machine (SVM classification, called convex-concave hull. We use the Jarvis march method to decide the concave (nonconvex hull for the inseparable points. Finally the vertices of the convex-concave hull are applied for SVM training.

  1. Basic dye adsorption onto an agro-based waste material--sesame hull (Sesamum indicum L.).

    Science.gov (United States)

    Feng, Yanfang; Yang, Fan; Wang, Yongqian; Ma, Li; Wu, Yonghong; Kerr, Philip G; Yang, Linzhang

    2011-11-01

    The aim of this project was to establish an economical and environmentally benign biotechnology for removing methylene blue (MB) from wastewater. The adsorption process of MB onto abandoned sesame hull (Sesamum indicum L.) (SH) was investigated in a batch system. The results showed that a wide range of pH (3.54-10.50) was favorable for the adsorption of MB onto SH. The Langmuir model displayed the best fit for the isothermal data. The exothermic adsorption process fits a pseudo-second-order kinetic model. The maximum monolayer adsorption capacity (359.88 mg g(-1)) was higher than most previously investigated low-cost bioadsorbents (e.g., peanut hull, wheat straw, etc.). This study indicated that sesame hull is a promising, unconventional, affordable and environmentally friendly bio-measure that is easily deployed for removing high levels of MB from wastewater. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    Science.gov (United States)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 1013 to 1015 n/cm2. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 1015 to 1016 n/cm2 with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  3. Post Irradiation Evaluation of Thermal Control Coatings and Solid Lubricants to Support Fission Surface Power Systems

    Science.gov (United States)

    Bowman, Cheryl L.; Jaworske, Donald A.; Stanford, Malcolm K.; Persinger, Justin A.; Khorsandi, Behrooz; Blue, Thomas E.

    2007-01-01

    The development of a nuclear power system for space missions, such as the Jupiter Icy Moons Orbiter or a lunar outpost, requires substantially more compact reactor design than conventional terrestrial systems. In order to minimize shielding requirements and hence system weight, the radiation tolerance of component materials within the power conversion and heat rejection systems must be defined. Two classes of coatings, thermal control paints and solid lubricants, were identified as material systems for which limited radiation hardness information was available. Screening studies were designed to explore candidate coatings under a predominately fast neutron spectrum. The Ohio State Research Reactor Facility staff performed irradiation in a well characterized, mixed energy spectrum and performed post irradiation analysis of representative coatings for thermal control and solid lubricant applications. Thermal control paints were evaluated for 1 MeV equivalent fluences from 10(exp 13) to 10(exp 15) n per square centimeters. No optical degradation was noted although some adhesive degradation was found at higher fluence levels. Solid lubricant coatings were evaluated for 1 MeV equivalent fluences from 10(exp 15) to 10(exp 16) n per square centimeters with coating adhesion and flexibility used for post irradiation evaluation screening. The exposures studied did not lead to obvious property degradation indicating the coatings would have survived the radiation environment for the previously proposed Jupiter mission. The results are also applicable to space power development programs such as fission surface power for future lunar and Mars missions.

  4. Improved TPB-coated Light Guides for Liquid Argon TPC Light Detection Systems

    CERN Document Server

    Moss, Z; Collin, G; Conrad, J M; Jones, B J P; Moon, J; Toups, M; Wongjirad, T

    2014-01-01

    Scintillation light produced in liquid argon (LAr) must be shifted from 128 nm to visible wavelengths in light detection systems used for liquid argon time-projection chambers (LArTPCs). To date, LArTPC light collection systems have employed tetra phenyl butadiene (TPB) coatings on photomultiplier tubes (PMTs) or plates placed in front of the PMTs. Recently, a new approach using TPB-coated light guides was proposed. In this paper, we report on light guides with improved attenuation lengths above 100 cm when measured in air. This is an important step in the development of meter-scale light guides for future LArTPCs. Improvements come from using a new acrylic-based coating, diamond-polished cast UV transmitting acrylic bars, and a hand-dipping technique to coat the bars.

  5. A scoring system for coat and tail condition in ringtailed lemurs, Lemur catta.

    Science.gov (United States)

    Berg, Wiebke; Jolly, Alison; Rambeloarivony, Hajarimanitra; Andrianome, Vonjy; Rasamimanana, Hantanirina

    2009-03-01

    Coat condition can be influenced by a wide variety of disorders and thus provides a useful tool for noninvasive health and welfare assessments in wild and captive animals. Using Lemur catta as an exemplar, we offer a 6-step scoring system for coat and tail condition, ranging from perfectly fluffy to half or more of body and tail being hairless. The categories are described in detail and illustrated with sample pictures from a wild population in Berenty Reserve, Madagascar. Furthermore, we elaborate on intermediate conditions and discoloration of fur. Coat condition scoring allows the comparison between years, seasons, and the effect of toxin, disease or stress. Although this system was developed for wild L. catta, we believe it can also be of value for other species. We recommend scoring coat condition in healthy wild mammal populations to give a baseline on yearly and seasonal variations vs. deteriorating health conditions or pathology. (c) 2009 Wiley-Liss, Inc.

  6. Influence of Heat Treatment on the Bond Coat Cyclic Oxidation Behaviour in an Air-plasma-sprayed Thermal Barrier Coating System

    Institute of Scientific and Technical Information of China (English)

    W.R. Chen; X. Wu; B.R. Marple; P.C. Patnaik

    2004-01-01

    It is generally believed that a thermally grown oxide (TGO) layer of alumina provides enhanced protection to the metallic bond coat in thermal barrier coating (TBC) systems at elevated temperatures. However, in an air-plasma-sprayed (APS) TBC system with Co-32Ni-21Cr-8A1-0.5Y (wt%) bond coat, the TGO layer formed upon thermal exposure in air was predominantly chromia and spinels, which would not effectively protect the bond coat at above 1000℃. In addition,mixed oxides of chromia, spinel and nickel oxide formed heterogeneously between the ceramic coating and CoNiCrAlY bond coat, which would promote crack initiation and lead to premature TBC failure. A heat treatment in a low-pressure condition was applied to the as-sprayed TBC system, with the aim to produce an alumina layer as well as reduce the amount of detrimental oxides. The influence of this low-pressure oxidation treatment (LPOT) on the bond coat cyclic oxidation behaviour of the TBC system was also investigated.

  7. Influence of Heat Treatment on the Bond Coat Cyclic Oxidation Behaviour in an Air-plasma-sprayed Thermal Barrier Coating System

    Institute of Scientific and Technical Information of China (English)

    W.R.Chen; X.Wu; B.R.Marple; P.C.Patnaik

    2004-01-01

    It is generally believed that a thermally grown oxide (TGO) layer of alumina provides enhanced protection to the metallic bond coat in thermal barrier coating (TBC) systems at elevated temperatures. However, in an air-plasma-sprayed (APS) TBC system with Co-32Ni-21Cr-8A1-0.5Y (wt%) bond coat, the TGO layer formed upon thermal exposure in air was predominantly chromia and spinels, which would not effectively protect the bond coat at above 1000℃. In addition, mixed oxides of chromia, spinel and nickel oxide formed heterogeneously between the ceramic coating and CoNiCrA1Y bond coat, which would promote crack initiation and lead to premature TBC failure. A heat treatment in a low-pressure condition was applied to the as-sprayed TBC system, with the aim to produce an alumina layer as well as reduce the amount of detrimental oxides. The influence of this low-pressure oxidation treatment (LPOT) on the bond coat cyclic oxidation behaviour of the TBC system was also investigated.

  8. Portable Handheld Laser Small Area Supplemental Coatings Removal System

    Science.gov (United States)

    2006-05-01

    Reference (5)) DMB (Wheat-Starch) (Reference (2)) Flash Lamp (Reference (6) CO2 Laser (Reference (1)) Plasma Etching (Reference (3)) Excimer ... excimer , dye, or semiconductor. The lasing mediums most commonly used for coating removal are solid-state, gas, or semiconductor. • Solid-state...infrared light at 1,064 nanometers (nm) and can be delivered via fiber optical cable. • Gas lasers commonly use helium, helium-neon, argon , or CO2 as

  9. Final Scientific/Technical Report "Arc Tube Coating System for Color Consistency"

    Energy Technology Data Exchange (ETDEWEB)

    Buelow, Roger; Jenson, Chris; Kazenski, Keith

    2013-03-21

    DOE has enabled the use of coating materials using low cost application methods on light sources to positively affect the output of those sources. The coatings and light source combinations have shown increased lumen output of LED fixtures (1.5%-2.0%), LED arrays (1.4%) and LED powered remote phosphor systems Philips L-Prize lamp (0.9%). We have also demonstrated lifetime enhancements (3000 hrs vs 8000 hrs) and shifting to higher CRI (51 to 65) in metal halide high intensity discharge lamps with metal oxide coatings. The coatings on LEDs and LED products are significant as the market is moving increasingly more towards LED technology. Enhancements in LED performance are demonstrated in this work through the use of available materials and low cost application processes. EFOI used low refractive index fluoropolymers and low cost dipping processes for application of the material to surfaces related to light transmission of LEDs and LED products. Materials included Teflon AF, an amorphous fluorinated polymer and fluorinated acrylic monomers. The DOE SSL Roadmap sets goals for LED performance moving into the future. EFOI's coating technology is a means to shift the performance curve for LEDs. This is not limited to one type of LED, but is relevant across LED technologies. The metal halide work included the use of sol-gel solutions resulting in silicon dioxide and titanium dioxide coatings on the quartz substrates of the metal halide arc tubes. The coatings were applied using low cost dipping processes.

  10. Monitoring Local Strain in a Thermal Barrier Coating System Under Thermal Mechanical Gas Turbine Operating Conditions

    Science.gov (United States)

    Manero, Albert; Sofronsky, Stephen; Knipe, Kevin; Meid, Carla; Wischek, Janine; Okasinski, John; Almer, Jonathan; Karlsson, Anette M.; Raghavan, Seetha; Bartsch, Marion

    2015-07-01

    Advances in aircraft and land-based turbine engines have been increasing the extreme loading conditions on traditional engine components and have incited the need for improved performance with the use of protective coatings. These protective coatings shield the load-bearing super alloy blades from the high-temperature combustion gases by creating a thermal gradient over their thickness. This addition extends the life and performance of blades. A more complete understanding of the behavior, failure mechanics, and life expectancy for turbine blades and their coatings is needed to enhance and validate simulation models. As new thermal-barrier-coated materials and deposition methods are developed, strides to effectively test, evaluate, and prepare the technology for industry deployment are of paramount interest. Coupling the experience and expertise of researchers at the University of Central Florida, The German Aerospace Center, and Cleveland State University with the world-class synchrotron x-ray beam at the Advanced Photon Source in Argonne National Laboratory, the synergistic collaboration has yielded previously unseen measurements to look inside the coating layer system for in situ strain measurements during representative service loading. These findings quantify the in situ strain response on multilayer thermal barrier coatings and shed light on the elastic and nonelastic properties of the layers and the role of mechanical load and internal cooling variations on the response. The article discusses the experimental configuration and development of equipment to perform in situ strain measurements on multilayer thin coatings and provides an overview of the achievements thus far.

  11. Investigation of dynamic characteristics of a rotor system with surface coatings

    Science.gov (United States)

    Yang, Yang; Cao, Dengqing; Wang, Deyou

    2017-02-01

    A Jeffcott rotor system with surface coatings capable of describing the mechanical vibration resulting from unbalance and rub-impact is formulated in this article. A contact force model proposed recently to describe the impact force between the disc and casing with coatings is employed to do the dynamic analysis for the rotor system with rubbing fault. Due to the variation of penetration, the contact force model is correspondingly modified. Meanwhile, the Coulomb friction model is applied to simulate the friction characteristics. Then, the case study of rub-impact with surface coatings is simulated by the Runge-Kutta method, in which a linear interpolation method is adopted to predict the rubbing instant. Moreover, the dynamic characteristics of the rotor system with surface coatings are analyzed in terms of bifurcation plot, waveform, whirl orbit, Poincaré map and spectrum plot. And the effects of the hardness of surface coatings on the response are investigated as well. Finally, compared with the classical models, the modified contact force model is shown to be more suitable to solve the rub-impact of aero-engine with surface coatings.

  12. FPSO Global Strength and Hull Optimization

    Institute of Scientific and Technical Information of China (English)

    Junyuan Ma; Jianhua Xiao; Rui Ma; Kai Cao

    2014-01-01

    Global strength is a significant item for floating production storage and offloading (FPSO) design, and steel weight plays an important role in the building costs of FPSO. It is the main task to consider and combine these two aspects by optimizing hull dimensions. There are many optional methods for the global strength analysis. A common method is to use the ABS FPSO Eagle software to analyze the global strength including the rule check and direct strength analysis. And the same method can be adopted for the FPSO hull optimization by changing the depth. After calculation and optimization, the results are compared and analyzed. The results can be used as a reference for the future design or quotation purpose.

  13. TLP hull structural design and analysis

    Institute of Scientific and Technical Information of China (English)

    Yang Jiahui; Ren Michael

    2013-01-01

    Tension leg platform (TLP) has been one of the most favorite deep-water platform concepts for offshore oil and gas field exploration and development.As of now,a total of 24 TLPs have been installed worldwide with 3 more to be installed in the near future and 5 more under design.Most of these installations are in the Gulf of Mexico (GoM).Water depths for these TLP installations range from 150 m to 1 600 m.It is highly expected that China will have her first TLP designed,fabricated,and installed in the very near future.In order to satisfy the need for a unified hull structural design practice,this paper presents the design philosophy of a conventional TLP hull structure with emphases on critical structural components design and analysis methodologies.

  14. Deposition of hybrid organic-inorganic composite coatings using an atmospheric plasma jet system.

    Science.gov (United States)

    Dembele, Amidou; Rahman, Mahfujur; Reid, Ian; Twomey, Barry; MacElroy, J M Don; Dowling, Denis P

    2011-10-01

    The objective of this study is to investigate the influence of alcohol addition on the incorporation of metal oxide nanoparticles into nm thick siloxane coatings. Titanium oxide (TiO2) nanoparticles with diameters of 30-80 nm were incorporated into an atmospheric plasma deposited tetramethylorthosilicate (TMOS) siloxane coating. The TMOS/TiO2 coating was deposited using the atmospheric plasma jet system known as PlasmaStream. In this system the liquid precursor/nanoparticle mixture is nebulised into the plasma. It was observed that prior to being nebulised the TiO2 particles agglomerated and settled over time in the TMOS/TiO2 mixture. In order to obtain a more stable nanoparticle/TMOS suspension the addition of the alcohols methanol, octanol and pentanol to this mixture was investigated. The addition of each of these alcohols was found to stabilise the nanoparticle suspension. The effect of the alcohol was therefore assessed with respect to the properties of the deposited coatings. It was observed that coatings deposited from TMOS/TiO2, with and without the addition of methanol were broadly similar. In contrast the coatings deposited with octanol and pentanol addition to the TMOS/TiO2 mixture were significantly thicker, for a given set of deposition parameters and were also more homogeneous. This would indicate that the alcohol precursor was incorporated into the plasma polymerised siloxane. The incorporation of the organic functionality from the alcohols was confirmed from FTIR spectra of the coatings. The difference in behaviour with alcohol type is likely to be due to the lower boiling point of methanol (65 degrees C), which is lower than the maximum plasma temperature measured at the jet orifice (77 degrees C). This temperature is significantly lower than the 196 degrees C and 136 degrees C boiling points of octanol and pentanol respectively. The friction of the coatings was determined using the Pin-on-disc technique. The more organic coatings deposited with

  15. The Aerodynamic Forces on Airship Hulls

    Science.gov (United States)

    Munk, M. M.

    1979-01-01

    The new method for making computations in connection with the study of rigid airships, which was used in the investigation of Navy's ZR-1 by the special subcommittee of the National Advisory Committee for Aeronautics appointed for this purpose is presented. The general theory of the air forces on airship hulls of the type mentioned is described and an attempt was made to develop the results from the very fundamentals of mechanics.

  16. The hull number of an oriented graph

    Directory of Open Access Journals (Sweden)

    Gary Chartrand

    2003-01-01

    Full Text Available We present characterizations of connected graphs G of order n≥2 for which h+(G=n. It is shown that for every two integers n and m with 1≤n−1≤m≤(n2, there exists a connected graph G of order n and size m such that for each integer k with 2≤k≤n, there exists an orientation of G with hull number G.

  17. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Jordi Perez-Mariano; Angel Sanjurjo

    2006-06-30

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this period, we analyzed several coated and exposed samples of 409 steel by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). We report here on findings of this analysis: (1) A SS409 coupon that was coated with multilayered combined nitrides of Ti, Al, and Si showed adherent coatings on the surface; (2) A similarly coated coupon, after exposure to simulated coal gas at 900 C for 300 h, revealed that the coating has cracked during the exposure; (3) An SS409 coupon that was coated with nitrides of Ti and Si with a barrier layer of tungsten in between to improve the adhesion of the coating and to prevent outward diffusion of iron to the surface. (4) A porous coupon was coated with nitrides of Ti and Al and examination of the coupon revealed deposition of Ti at the interior surfaces. A similarly prepared coupon was exposed to simulated coal gas at 370 C for 300 h, and it showed no corrosion.

  18. Surface morphology of spray-dried nanoparticle-coated microparticles designed as an oral drug delivery system

    Directory of Open Access Journals (Sweden)

    R. C. R. Beck

    2008-06-01

    Full Text Available This paper was devoted to studying the influence of coating material (nanocapsules or nanospheres, drug model (diclofenac, acid or salt and method of preparation on the morphological characteristics of nanoparticle-coated microparticles. The cores of microparticles were obtained by spray drying or evaporation and the coating was applied by spray drying. SEM analyses showed nanostructures coating the surface of nanocapsule-coated microparticles and a rugged surface for nanosphere-coated microparticles. The decrease in their surface areas was controlled by the nanoparticulated system, which was not dependent on microparticle size. Optical microscopy and X-ray analyses indicated that acid diclofenac crystals were present in formulations prepared with the acid as well as in the nanocapsule-coated microparticles prepared with the salt. The control of coating is dependent on the use of nanocapsules or nanospheres and independent of either the characteristics of the drug or the method of preparing the core.

  19. Thermodynamic aspects of the coating formation through mechanochemical synthesis in vibration technology systems

    Science.gov (United States)

    Shtyn, S. U.; Lebedev, V. A.; Gorlenko, A. O.

    2017-02-01

    On the basis of thermodynamic concepts of the process, we proposed an energy model that reflects the mechanochemical essence of coating forming in terms of vibration technology systems, which takes into account the contribution to the formation of the coating, the increase of unavailable energy due to the growth of entropy, the increase in the energy of elastic-plastic crystal lattice distortion as a result of the mechanical influence of working environment indenters, surface layer internal energy change which occurs as a result of chemical interaction of the contacting media. We proposed adhesion strength of the local volume modified through processing as a criterion of the energy condition of the formed coating. We established analytical dependence which helps to obtain the coating strength of the material required by operating conditions.

  20. Benchmarking TPB-coated Light Guides for Liquid Argon TPC Light Detection Systems

    CERN Document Server

    Baptista, B; Chiu, C; Conrad, J M; Ignarra, C M; Jones, B J P; Katori, T; Mufson, S

    2012-01-01

    Scintillation light from liquid argon is produced at 128 nm and thus must be shifted to visible wavelengths in light detection systems used for Liquid Argon Time Projection Chambers (LArTPCs). To date, designs have employed tetraphenyl butadiene (TPB) coatings on photomultiplier tubes (PMTs) or plates placed in front of the PMTs. Recently, a new approach using TPB-coated light guides was proposed. In this paper, we show that the response of lightguides coated with TPB in a UV Transmitting (UVT) acrylic matrix is very similar to that of a coating using a polystyrene (PS) matrix. We obtain a factor of three higher light yield than has been previously reported from lightguides. This paper provides information on the response of the lightguides so that these can be modeled in simulations for future LArTPCs. This paper also identifies areas of R&D for potential improvements in the lightguide response

  1. THE RESEARCH TECHNIQUES FOR ANALYSIS OF MECHANICAL AND TRIBOLOGICAL PROPERTIES OF COATING-SUBSTRATE SYSTEMS

    Directory of Open Access Journals (Sweden)

    Kinga CHRONOWSKA-PRZYWARA

    2014-06-01

    Full Text Available The article presents research techniques for the analysis of both mechanical and tribological properties of thin coatings applied on highly loaded machine elements. In the Institute of Machine Design and Exploitation, AGH University of Science and Technology students of the second level of Mechanical Engineering study tribology attending laboratory class. Students learn on techniques for mechanical and tribological testing of thin, hard coatings deposited by PVD and CVD technologies. The program of laboratories contains micro-, nanohardness and Young's modulus measurements by instrumental indentations and analysys of coating to substrate adhesion by scratch testing. The tribological properties of the coating-substrate systems are studied using various techniques, mainly in point contact load conditions with ball-on-disc and block-on-ring tribomiters as well as using ball cratering method in strongly abrasive suspensions.

  2. Reducing Friction and Wear of Tribological Systems through Hybrid Tribofilm Consisting of Coating and Lubricants

    Directory of Open Access Journals (Sweden)

    Shuichiro Yazawa

    2014-06-01

    Full Text Available The role of surface protective additives becomes vital when operating conditions become severe and moving components operate in a boundary lubrication regime. After protecting film is slowly removed by rubbing, it can regenerate through the tribochemical reaction of the additives at the contact. However, there are limitations about the regeneration of the protecting film when additives are totally consumed. On the other hand, there are a lot of hard coatings to protect the steel surface from wear. These can enable the functioning of tribological systems, even in adverse lubrication conditions. However, hard coatings usually make the friction coefficient higher, because of their high interfacial shear strength. Amongst hard coatings, diamond-like carbon (DLC is widely used, because of its relatively low friction and superior wear resistance. In practice, conventional lubricants that are essentially formulated for a steel/steel surface are still used for lubricating machine component surfaces provided with protective coatings, such as DLCs, despite the fact that the surface properties of coatings are quite different from those of steel. It is therefore important that the design of additive molecules and their interaction with coatings should be re-considered. The main aim of this paper is to discuss the DLC and the additive combination that enable tribofilm formation and effective lubrication of tribological systems.

  3. Apatite coating of electrospun PLGA fibers using a PVA vehicle system carrying calcium ions.

    Science.gov (United States)

    Kim, In Ae; Rhee, Sang-Hoon

    2010-01-01

    A novel method to coat electrospun poly(D,L-lactic-co-glycolic acid) (PLGA) fiber surfaces evenly and efficiently with low-crystalline carbonate apatite crystals using a poly(vinyl alcohol) (PVA) vehicle system carrying calcium ions was presented. A non-woven PLGA fabric was prepared by electrospinning: a 10 wt% PLGA solution was prepared using 1,1,3,3-hexafluoro-2-propanol as a solvent and electrospun under a electrical field of 1 kV/cm using a syringe pump with a flowing rate of 3 ml/h. The non-woven PLGA fabric, 12 mm in diameter and 1 mm in thickness, was cut and then coated with a PVA solution containing calcium chloride dihydrate (specimen PPC). As controls, pure non-woven PLGA fabric (specimen P) and fabric coated with a calcium chloride dihydrate solution without PVA (specimen PC) were also prepared. Three specimens were exposed to simulated body fluid for 1 week and this exposure led to form uniform and complete apatite coating layer on the fiber surfaces of specimen PPC. However, no apatite had formed to the fiber surfaces of specimen P and only inhomogeneous coating occurred on the fiber surfaces of specimen PC. These results were explained in terms of the calcium chelating and adhesive properties of PVA vehicle system. The practical implication of the results is that this method provides a simple but efficient technique for coating the fiber surface of an initially non-bioactive material with low-crystalline carbonate apatite.

  4. On Rational Design of Double Hull Tanker Structures against Collision

    DEFF Research Database (Denmark)

    Paik, Jeom Kee; Chung, Jang Young; Choe, Ich Hung

    1999-01-01

    in the present study were (i) developing a framework for the collision design procedure for double hull tanker structures, (ii) experimental investigation of the structural crashworthiness of the collided vessels in collision or stranding, using double skinned structural models, (iii) validation of the special...... be useful for the rational design of new double hull tanker side structures against ship collision to reduced the risk of oil pollution and for the collision resistance evaluation of existing double hull tanker structures....

  5. Refractory Materials for Flame Deflector Protection System Corrosion Control: Coatings Systems Literature Survey

    Science.gov (United States)

    Calle, Luz M.; Hintze, Paul E.; Parlier, Christopher R.; Sampson, Jeffrey W.; Coffman, Brekke E.; Coffman, Brekke E.; Curran, Jerome P.; Kolody, Mark R.; Whitten, Mary; Perisich, Steven; Trejo, David

    2009-01-01

    When space vehicles are launched, extreme heat, exhaust, and chemicals are produced and these form a very aggressive exposure environment at the launch complex. The facilities in the launch complex are exposed to this aggressive environment. The vehicle exhaust directly impacts the flame deflectors, making these systems very susceptible to high wear and potential failure. A project was formulated to develop or identify new materials or systems such that the wear and/or damage to the flame deflector system, as a result of the severe environmental exposure conditions during launches, can be mitigated. This report provides a survey of potential protective coatings for the refractory concrete lining on the steel base structure on the flame deflectors at Kennedy Space Center (KSC).

  6. The Development of Environmental Barrier Coating Systems for SiC-SiC Ceramic Matrix Composites: Environment Effects on the Creep and Fatigue Resistance

    Science.gov (United States)

    Zhu, Dongming; Ghosn, Louis J.

    2014-01-01

    Topics covered include: Environmental barrier coating system development: needs, challenges and limitations; Advanced environmental barrier coating systems (EBCs) for CMC airfoils and combustors; NASA EBC systems and material system evolutions, Current turbine and combustor EBC coating emphases, Advanced development, processing, testing and modeling, EBC and EBC bond coats: recent advances; Design tool and life prediction of coated CMC components; Advanced CMC-EBC rig demonstrations; Summary and future directions.

  7. Research on the Design of Hull Crashworthiness Structure based on Sandwich Plate System%基于SPS的船体耐撞结构设计研究

    Institute of Scientific and Technical Information of China (English)

    刘昆; 王自力; 张延昌; 唐文勇

    2014-01-01

    Sandwich Plate System (SPS) with superior mechanical performance is widely used in ship repairing. The core has good buffer function so that it can be used as crashworthiness structures. Based on ABAQUS, the crashworthiness of SPS side structure under collision load was analyzed, such as damage deformation, collision force and energy absorption. Then the crashworthiness of SPS was compared with traditional side structure. The results show that SPS side structure has better crashwor-thiness than traditional side structure.%夹层板系统(SPS)具有优良的力学性能,因此被广泛地应用于船舶修造过程。因其夹芯层具有良好的缓冲作用,所以可以用作耐撞结构以提高舰船的碰撞性能。文章基于大型商业有限元分析软件ABAQUS,分析了SPS舷侧结构的碰撞性能,重点讨论了损伤变形、碰撞力和能量吸收等碰撞参数,并与传统舷侧结构的碰撞性能进行比较。研究表明:SPS舷侧结构较传统舷侧结构在总质量相当的情况下,极限撞深提高且在极限撞深时吸能也提高较多,表现出了优越的耐撞性能。

  8. Hydrodynamics of single-deadrise hulls and their catamaran configurations

    Directory of Open Access Journals (Sweden)

    Ghazi S. Bari

    2017-05-01

    Full Text Available Asymmetric planing hulls are often used on high-speed catamarans. In this study, a linearized potential-flow method is applied for modeling steady hydrodynamics of single asymmetric hulls and their catamaran setups. Numerical results are validated with available experimental data and empirical correlations. Parametric calculation results are presented for the lift coefficient and the center of pressure for variable hull geometry, spacings, and speed regimes. The lift coefficient is found to increase at smaller hull spacings and decrease at higher Froude numbers and higher deadrise angles.

  9. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Angel Sanjurjo

    2005-09-01

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this reporting period, we conducted several exposure tests with coated and uncoated coupons including a ''500-h'' test. The first experiment was a 316-h test and was designed to look at the performance of Ti/Ta nitride coatings, which seemed to fare the best in earlier tests. The next experiment was a 112-h test with a range of pure metals and commercially available materials. Its purpose was to help identify those metals that best withstood gasifier environment, and hence should be good ingredients for coatings. Finally, we ran a ''500-h'' test, which was also our milestone, with coupons coated with Ti/Ta nitride or Cr/Al coatings.

  10. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Jordi Perez-Mariano; Angel Sanjurjo

    2006-12-31

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this period, we analyzed several coated and exposed samples of 409 steel by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX), and report on the findings of four samples: (1) Analysis of two porous coupons after exposure to the porous metal particulate filter of the coal gasification power plant at 370 C for 2140 hours revealed that corrosion takes place in the bulk of the sample while the most external zone surface survived the test. (2) Coating and characterization of several porous 409 steel coupons after being coated with nitrides of Ti, Al and/or Si showed that adjusting experimental conditions results in thicker coatings in the bulk of the sample. (3) Analysis of coupons exposed to simulated coal gas at 370 C for 300 hours showed that a better corrosion resistance is achieved by improving the coatings in the bulk of the samples.

  11. A brief review of environmentally benign antifouling and foul-release coatings for marine applications

    NARCIS (Netherlands)

    Buskens, P.J.P.; Wouters, M.E.L.; Rentrop, C.H.A.; Vroon, Z.A.E.P.

    2013-01-01

    Antifouling coatings for ship hulls are a very important topic in coating research. They are essential with respect to fuel consumption of ships: without antifouling coating, biological species start to adhere to the ship's exterior, leading to a gradual increase in fuel consumption. To date, the wo

  12. A brief review of environmentally benign antifouling and foul-release coatings for marine applications

    NARCIS (Netherlands)

    Buskens, P.J.P.; Wouters, M.E.L.; Rentrop, C.H.A.; Vroon, Z.A.E.P.

    2013-01-01

    Antifouling coatings for ship hulls are a very important topic in coating research. They are essential with respect to fuel consumption of ships: without antifouling coating, biological species start to adhere to the ship's exterior, leading to a gradual increase in fuel consumption. To date, the

  13. Structural and acoustic responses of a submarine hull due to propeller forces

    Science.gov (United States)

    Merz, Sascha; Kinns, Roger; Kessissoglou, Nicole

    2009-08-01

    The low frequency structural and acoustic responses of a simplified axisymmetric submarine model to fluctuating propeller forces along the submarine axis are investigated. The forces arise from a hydrodynamic mechanism and are transmitted from the propeller to the submarine hull through both the shaft and the fluid. Numerical models have been developed to simulate the strongly coupled structure-fluid interaction of a submerged vessel in the frequency domain. The structure is modelled using the finite element method, so that more complex features such as ring-stiffeners, bulkheads and the propulsion system can be taken into account. A simple, passive vibration attenuation system known as a resonance changer is included in the model of the propeller/shafting system. The surrounding fluid is modelled using the boundary element method. The influence and importance of model parameters such as structural stiffness and fluid loading effects are investigated. Due to the fluctuating propeller forces, the hull is excited by axial structural forces transmitted through the propeller/shafting system as well as by acoustic dipoles, where the dipoles are correlated to the structural forces in strength and direction. The acoustic dipole at the propeller also radiates sound directly to the far field of the surrounding fluid. It is demonstrated that the performance of the RC is negatively influenced at frequencies above the fundamental axial resonance of the hull by the effect of forces transmitted through the fluid. Another problem arises due to increased axial movement of the propeller, when the RC is optimised to minimise excitation of the hull via the propeller shaft. This results in an additional sound field that excites the submarine hull in a similar manner to the fluid forces that arise directly from the hydrodynamic mechanism.

  14. Residual stress analysis of the thermal barrier coating system by considering the plasma spraying process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myung Jae; Lee, Byung Chai [KAIST, Daejeon (Korea, Republic of); Lim, Jang Gyun; Kim, Moon Ki [Sungkyunkwan University, Suwon (Korea, Republic of)

    2014-06-15

    The residual stress is the key factor causing the reliability problem of thermal barrier coating (TBC). The failure of plasma spray coatings due to residual stresses is a serious and recurring problem of TBC. The difference of thermal expansion coefficient between the substrate and each coating combined with temperature evolution and temperature gradients during deposition process determine the residual stress for the whole TBC system. The magnitudes and distributions of the residual stresses are affected by deposition process and deposition characteristics. Most of FEA (finite element analysis) has been performed under the assumption that the multilayer coating system is stacked at once without considering the deposition process during plasma spraying. In this research, FEA for a coupled heat transfer and elastic-plastic thermal stress was performed to obtain the more detailed and reliable result of residual stress of the TBC system using the element activation/deactivation technique. The residual stress variation from the start of plasma spraying to cooling stage with room temperature was obtained systematically considering the deposition process. It can be used as reference data to improve the performance of TBC. In addition, the relationship between residual stress and coating conditions such as cooling rate and time is also examined thoroughly.

  15. Galvanic Liquid Applied Coating System For Protection of Embedded Steel Surfaces from Corrosion

    Science.gov (United States)

    Curran, Joseph; Curran, Jerome; Voska, N. (Technical Monitor)

    2002-01-01

    Corrosion of reinforcing steel in concrete is an insidious problem facing Kennedy Space Center (KSC), other Government Agencies, and the general public. These problems include KSC launch support structures, highway bridge infrastructure, and building structures such as condominium balconies. Due to these problems, the development of a Galvanic Liquid Applied Coating System would be a breakthrough technology having great commercial value for the following industries: Transportation, Infrastructure, Marine Infrastructure, Civil Engineering, and the Construction Industry. This sacrificial coating system consists of a paint matrix that may include metallic components, conducting agents, and moisture attractors. Similar systems have been used in the past with varying degrees of success. These systems have no proven history of effectiveness over the long term. In addition, these types of systems have had limited success overcoming the initial resistance between the concrete/coating interface. The coating developed at KSC incorporates methods proven to overcome the barriers that previous systems could not achieve. Successful development and continued optimization of this breakthrough system would produce great interest in NASA/KSC for corrosion engineering technology and problem solutions. Commercial patents on this technology would enhance KSC's ability to attract industry partners for similar corrosion control applications.

  16. A Hull cell study of a NiW electrolyte and evaluation of its properties; Estudio en celula Hull de un bano electrolitico de NiW y evaluacion de sus propiedades

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Urrutia, I.; Diez, J. A.; Muller, C.; Calvillo, P.

    2009-07-01

    Interest in NiW coatings has grown in recent years due to its favourable properties such as hardness, and resistance to both wear and corrosion, making it one of the actual alternatives to hard chromium coatings. In this work, we have undertaken a Hull cell study, investigating the influence of the metal concentration, temperature, pH and current density on the composition of the alloy formed and its thickness. We have also studied the most important properties of the NiW deposits, including morphology, hardness, and resistance to abrasion and corrosion. (Author) 9 refs.

  17. Advanced thermal barrier system bond coatings for use on Ni, Co-, and Fe-base alloy substrates

    Science.gov (United States)

    Stecura, S.

    1985-01-01

    New and improved Ni-, Co-, and Fe-base bond coatings have been identified for the ZrO2-Y2O3 thermal barrier coatings to be used on NI-, Co-, and Fe-base alloy substrates. These bond coatings were evaluated in a cyclic furnace between 1120 and 1175 C. It was found that MCrAlYb (where M = Ni, Co, or Fe) bond coating thermal barrier systems. The longest life was obtained with the FeCrAlYb thermal barrier system followed by NiCrAlYb and CoCrAlYb thermal barrier systems in that order.

  18. Advanced Oxide Material Systems for 1650 C Thermal/Environmental Barrier Coating Applications

    Science.gov (United States)

    Zhu, Dong-Ming; Fox, Dennis S.; Bansal, Narottam P.; Miller, Robert A.

    2004-01-01

    Advanced thermal and environmental barrier coatings (TEBCs) are being developed for low-emission SiC/SiC ceramic matrix composite (CMC) combustor and vane applications to extend the CMC liner and vane temperature capability to 1650 C (3000 F) in oxidizing and water-vapor-containing combustion environments. The advanced 1650 C TEBC system is required to have a better high-temperature stability, lower thermal conductivity, and more resistance to sintering and thermal stress than current coating systems under engine high-heat-flux and severe thermal cycling conditions. In this report, the thermal conductivity and water vapor stability of selected candidate hafnia-, pyrochlore- and magnetoplumbite-based TEBC materials are evaluated. The effects of dopants on the materials properties are also discussed. The test results have been used to downselect the TEBC materials and help demonstrate the feasibility of advanced 1650 C coatings with long-term thermal cycling durability.

  19. Use of bicarbonate buffer systems for dissolution characterization of enteric-coated proton pump inhibitor tablets.

    Science.gov (United States)

    Shibata, Hiroko; Yoshida, Hiroyuki; Izutsu, Ken-Ichi; Goda, Yukihiro

    2016-04-01

    The aim of this study was to assess the effects of buffer systems (bicarbonate or phosphate at different concentrations) on the in vitro dissolution profiles of commercially available enteric-coated tablets. In vitro dissolution tests were conducted using an USP apparatus II on 12 enteric-coated omeprazole and rabeprazole tablets, including innovator and generic formulations in phosphate buffers, bicarbonate buffers and a media modified Hanks (mHanks) buffer. Both omeprazole and rabeprazole tablets showed similar dissolution profiles among products in the compendial phosphate buffer system. However, there were large differences between products in dissolution lag time in mHanks buffer and bicarbonate buffers. All formulations showed longer dissolution lag times at lower concentrations of bicarbonate or phosphate buffers. The dissolution rank order of each formulation differed between mHanks buffer and bicarbonate buffers. A rabeprazole formulation coated with a methacrylic acid copolymer showed the shortest lag time in the high concentration bicarbonate buffer, suggesting varied responses depending on the coating layer and buffer components. Use of multiple dissolution media during in vitro testing, including high concentration bicarbonate buffer, would contribute to the efficient design of enteric-coated drug formulations. © 2016 Royal Pharmaceutical Society, Journal of Pharmacy and Pharmacology.

  20. Horizontal direction drill shore approach - a unique field joint coating system

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, Robert; Lemuchi, Andre; Gudme, Carl [Canusa-CPS, Toronto, ON (Canada)

    2005-07-01

    High performance pipeline coatings such as 3-layer polypropylene (3LPP) have been developed to meet the more demanding applications of today's pipelines. For offshore applications, this coating type is ideal because it offers lay contractors a tough, virtually holiday free coating, which enhances lay speeds. However, the field joint on polypropylene-coated pipe is one of the challenges for contractors who want to maximize lay speed and minimize cost. In recent years, a polypropylene-based heat-shrinkable sleeve has been developed to overcome some of the issues that lay contractors had, and the system is in widespread use globally. At the point where offshore pipelines transition to onshore sections the construction has also been a major challenge. Recently, contractors have used a system whereby they trench or directionally drill the pipeline up the shore approach then directionally drill through sensitive areas beyond the beach. This minimizes the environmental impact at the shoreline and can be quite cost effective. Again, the challenge of a more universally accepted field joint solution for polypropylene-coated pipelines that could withstand the rigours of the construction method was present. (author)

  1. Creep Behavior of Hafnia and Ytterbium Silicate Environmental Barrier Coating Systems on SiC/SiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming; Fox, Dennis S.; Ghosn, Louis J.; Harder, Bryan

    2011-01-01

    Environmental barrier coatings will play a crucial role in future advanced gas turbine engines because of their ability to significantly extend the temperature capability and stability of SiC/SiC ceramic matrix composite (CMC) engine components, thus improving the engine performance. In order to develop high performance, robust coating systems for engine components, appropriate test approaches simulating operating temperature gradient and stress environments for evaluating the critical coating properties must be established. In this paper, thermal gradient mechanical testing approaches for evaluating creep and fatigue behavior of environmental barrier coated SiC/SiC CMC systems will be described. The creep and fatigue behavior of Hafnia and ytterbium silicate environmental barrier coatings on SiC/SiC CMC systems will be reported in simulated environmental exposure conditions. The coating failure mechanisms will also be discussed under the heat flux and stress conditions.

  2. Optimization of a Wcl6 CVD System to Coat UO2 Powder with Tungsten

    Science.gov (United States)

    Belancik, Grace A.; Barnes, Marvin W.; Mireles, Omar; Hickman, Robert

    2015-01-01

    In order to achieve deep space exploration via Nuclear Thermal Propulsion (NTP), Marshall Space Flight Center (MSFC) is developing W-UO2 CERMET fuel elements, with focus on fabrication, testing, and process optimization. A risk of fuel loss is present due to the CTE mismatch between tungsten and UO2 in the W-60vol%UO2 fuel element, leading to high thermal stresses. This fuel loss can be reduced by coating the spherical UO2 particles with tungsten via H2/WCl6 reduction in a fluidized bed CVD system. Since the latest incarnation of the inverted reactor was completed, various minor modifications to the system design were completed, including an inverted frit sublimer. In order to optimize the parameters to achieve the desired tungsten coating thickness, a number of trials using surrogate HfO2 powder were performed. The furnace temperature was varied between 930 C and 1000degC, and the sublimer temperature was varied between 140 C and 200 C. Each trial lasted 73-82 minutes, with one lasting 205 minutes. A total of 13 trials were performed over the course of three months, two of which were re-coatings of previous trials. The powder samples were weighed before and after coating to roughly determine mass gain, and Scanning Electron Microscope (SEM) data was also obtained. Initial mass results indicated that the rate of layer deposition was lower than desired in all of the trials. SEM confirmed that while a uniform coating was obtained, the average coating thickness was 9.1% of the goal. The two re-coating trials did increase the thickness of the tungsten layer, but only to an average 14.3% of the goal. Therefore, the number of CVD runs required to fully coat one batch of material with the current configuration is not feasible for high production rates. Therefore, the system will be modified to operate with a negative pressure environment. This will allow for better gas mixing and more efficient heating of the substrate material, yielding greater tungsten coating per trial.

  3. Extraction of starch from hulled and hull-less barley with papain and aqueous sodium hydroxide.

    Science.gov (United States)

    Sharma, Priyanka; Tejinder, S

    2014-12-01

    Starch was isolated from hulled (VJM 201) and hull-less (BL 134) barley with papain and aqueous sodium hydroxide treatments. For enzyme-assisted extraction, barley was steeped in water containing 0.2 % SO2 + 0.55 % lactic acid at 50° ± 2 °C for 4-5 h. The slurry was mixed with 0.4-2.0 g papain/kg barley and incubated at 50° ± 2 °C for 1-5 h. Aqueous sodium hydroxide (0.01-0.05 M) was added to the finely ground barley meal. The alkaline slurry was incubated at ambient temperature (25° ± 2 °C) for 15-60 min. The starch and grain fractions were isolated by screening and centrifugation. Increases in the time of treatment significantly affected the fiber, centrifugation and non-starch residue losses. Concentration of papain and sodium hydroxide had negligible effect on extraction losses. The enzyme-assisted extraction efficiency of starch was higher (80.7-84.6 %) than the alkaline method (70.9-83.7 %). The hulled barley showed higher extraction efficiency than the hull-less barley. The slurry treated with 0.4 g papain/kg barley for 5 h and 0.03 M sodium hydroxide for 60 min produced maximal yield of starch. Barley starch showed desirably high pasting temperature, water binding capacity and hold viscosity; and low final and setback viscosity compared with the commercial corn starch. The alkaline extracted hull-less barley starch showed exceptionally high peak and hold viscosities.

  4. 46 CFR 154.188 - Membrane tank: Inner hull steel.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Membrane tank: Inner hull steel. 154.188 Section 154.188 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... Structure § 154.188 Membrane tank: Inner hull steel. For a vessel with membrane tanks, the inner...

  5. 77 FR 59575 - Hull Identification Numbers for Recreational Vessels

    Science.gov (United States)

    2012-09-28

    ... SECURITY Coast Guard 33 CFR Part 181 Hull Identification Numbers for Recreational Vessels AGENCY: Coast... requesting public comments regarding the existing regulatory requirement to indicate a boat's model year as part of the 12-character Hull Identification Number (HIN). Under current regulations in 33 CFR part 181...

  6. Progressive hull removal from barley using the Fitzpatrick comminuting mill

    Science.gov (United States)

    The objective of the study was to explore an alternative use of the Fitzpatrick Comminuting Machine: to use it to remove the hull from hulled barley while keeping the barley kernel intact. Traditionally, this mill is used to grind material, but we have recently discovered that it also has the abili...

  7. Registration of Harriman low-phytate, hulled spring barley

    Science.gov (United States)

    The Agricultural Research Service, U.S. Department of Agriculture (USDA-ARS), has released 'Harriman', (Hordeum vulgare L.) (Reg. No. xxxxxx, P.I. xxxxxx). Harriman is a hulled, low-phytate barley, the second to be developed and released by the USDA-ARS. Compared to the previously released hulled, l...

  8. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Angel Sanjurjo

    2006-01-01

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this period we tested coated alloy coupons under conditions designed to mimic the conditions in the filter unit after the high-temperature heat recovery unit (HTHRU). The filter unit is another important area where corrosion has caused unscheduled downtime, and the remedy has been the use of sintered metal tubes made of expensive alloys such as inconel. The objective of our test was to determine if those coatings on 400-series steel that were not able to withstand the harsher conditions of the HTHRU, may be sufficiently resistant for use in the filter unit, at the reduced temperatures. Indeed, most of our coatings survived well; the exceptions were the coated porous samples of SS316. We continued making improvements to our coatings apparatus and the procedure began during the last quarter. As a result of these modifications, the coupons we are now producing are uniform. We describe the improved procedure for preparing diffusion coatings. Finally, because porous samples of steel in grades other than SS316 are not readily available, we also decided to procure SS409 powder and fabricate our own sintered porous coupons.

  9. Numerical assessment of functionally graded tungsten/EUROFER coating system for first wall applications

    Energy Technology Data Exchange (ETDEWEB)

    Qu, D.D., E-mail: dandna.qu@partner.kit.edu; Basuki, W.W.; Aktaa, J.

    2015-10-15

    Highlights: • Tungsten coatings with W/EUROFER functional graded (FG) interlayers on EUROFER substrates are investigated by means of finite element (FE) simulations as first wall (FW) application. • The FE simulations consider elasto-perfectly plastic and elasto-viscoplastic material models and the fabrication phase and operation phase. • The effects of FG-interlayers thicknesses on mitigating the residual stress and inelastic strain are studied. • Allowable number of cycles is calculated based on creep damage accumulation. - Abstract: Reduced activation ferritic/martensitic (RAFM) steels, e.g. EUROFER, are to be used as structural material for the first wall (FW) of future fusion power plants. The interaction between the plasma and the FW, especially physical sputtering, will limit the FW lifetime under normal operation. Therefore, a tungsten coating should be selected to protect the FW due to its low sputtering yield, low activation, high melting point and high thermal conductivity. However, the mismatch of thermo-physical properties between W and EUROFER induces large residual thermal stresses and even failure of components. Functionally graded material (FGM) is considered as an appropriate solution to mitigate the high residual stresses. In this work, W coatings on EUROFER substrates with W/EUROFER FG-layer (the coating system) are investigated by means of finite element (FE) simulations considering elasto-perfectly plastic and elasto-viscoplastic material models. For determining optimal parameters of the coating system the vacuum plasma spraying (VPS) fabrication process and the operation phase of the fusion reactor are simulated. Based on the FE results creep assessment of the coating system is performed demonstrating the gain in lifetime to be expected when using a FG-layer and investigating its dependence on the thickness of the FG-layer.

  10. DEMONSTRATION OF A NO-VOC/NO-HAP WOOD KITCHEN CABINET COATING SYSTEM

    Science.gov (United States)

    The report gives results of the development and demonstration of a no-VOC (volatile organic compound)/no-HAP (hazardous air pollutant) wood furniture coating system at two cabinet manufacturing plants: one in Portland, OR, and the other in Redwood City, CA. Technology transfer ef...

  11. Final Report on NASA Portable Laser Coating Removal Systems Field Demonstrations and Testing

    Science.gov (United States)

    Rothgeb, Matthew J; McLaughlin, Russell L.

    2008-01-01

    Processes currently used throughout the National Aeronautics and Space Administration (NASA) to remove corrosion and coatings from structures, ground service equipment, small parts and flight components result in waste streams consisting of toxic chemicals, spent media blast materials, and waste water. When chemicals are used in these processes they are typically high in volatile organic compounds (VOC) and are considered hazardous air pollutants (HAP). When blast media is used, the volume of hazardous waste generated is increased significantly. Many of the coatings historically used within NASA contain toxic metals such as hexavalent chromium, and lead. These materials are highly regulated and restrictions on worker exposure continue to increase. Most recently the Occupational Safety and Health Administration (OSHA) reduced the permissible exposure limit (PEL) for hexavalent chromium (CrVI) from 52 to 5 micrograms per cubic meter of air as an 8-hour time-weighted average. Hexavalent chromium is found in numerous pretreatment and primer coatings used within the Space Shuttle Program. In response to the need to continue to protect assets within the agency and the growing concern over these new regulations, NASA is researching different ways to continue the required maintenance of both facility and flight equipment in a safe, efficient, and environmentally preferable manner. The use of laser energy to prepare surfaces for a variety of processes, such as corrosion and coating removal, weld preparation, and non destructive evaluation (NDE) is a relatively new application of the technology that has been proven to be environmentally preferable and in many cases less labor intensive than currently used removal methods. The novel process eliminates VOCs and blast media and captures the removed coatings with an integrated vacuum system. This means that the only waste generated are the coatings that are removed, resulting in an overall cleaner process. The development of a

  12. Effect of an absorptive coating on solar energy storage in a Trombe wall system

    Energy Technology Data Exchange (ETDEWEB)

    Nwachukwu, N.P. [Nigeria Univ., Nsukka (Nigeria). Dept. of Mechanical Engineering; Okonkwo, W.I. [National Center for Energy Research and Development, Nsukka (Nigeria)

    2008-07-01

    An analysis is undertaken to show the effects of a range of coating absorptivity values on the improvement of heat transfer across a Trombe wall (which is used for passive solar heating) and to its enclosure. The analysis shows that enhanced heat delivery to the enclosure of a Trombe wall system is feasible with the application of an absorptive coating of a superior nature - characterized by high absorptivity and very low emissivity - on the heat-receiving surface of the wall and thus can be seen as a heat transfer enhancement technique. (author)

  13. Effect of an Absorptive Coating on Solar Energy Storage in a Thrombe wall system

    Energy Technology Data Exchange (ETDEWEB)

    Nwachukwu, Nwosu P. [Department of Mechanical Engineering, University of Nigeria, Nsukka (Nigeria); Okonkwo, Wilfred I. [National Center for Energy Research and Development (NCERD), Nsukka (Nigeria)

    2008-07-01

    An analysis is undertaken to show the effects of a range of coating absorptivity values on the improvement of heat transfer across a Trombe wall (which is used for passive solar heating) and to its enclosure. The analysis shows that enhanced heat delivery to the enclosure of a Trombe wall system is feasible with the application of an absorptive coating of a superior nature - characterized by high absorptivity and very low emissivity - on the heat-receiving surface of the wall and thus can be seen as a heat transfer enhancement technique. (author)

  14. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Angel Sanjurjo

    2005-12-01

    Heat exchangers, particle filters, turbines, and other components in an integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high-alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this reporting period, we conducted a simulated gasifier test primarily with TiN-coated steel samples. Although the test showed these coatings to offer significant protection against corrosion, they also revealed a lack of uniformity in the coatings. We spent a considerable amount of effort improving our coatings procedure as well as the fluidized bed reactor and its heater. Based on the results collected thus far, we selected 12 samples and sent them to ConocoPhillips for testing in their gasifier at the Wabash River Energy plant.

  15. Impact of surface coated magnetite used in magnetic drug delivery system on immune response

    Science.gov (United States)

    Oaku, Yoshihiro; Tamada, Junya; Mishima, Fumihito; Akiyama, Yoko; Osako, Mariana Kiomy; Koriyama, Hiroshi; Nakagami, Hironori; Nishijima, Shigehiro

    2015-05-01

    Magnetic drug delivery system (MDDS) is a technique to effectively accumulate drugs, which are combined with ferromagnetic particles, into the affected area using magnetic force control. This study intends to apply MDDS for immunotherapy by enhancing immune responses by a surface treatment of a ferromagnetic particle. The objective of this study is to give the adjuvant effect to a ferromagnetic particle by the surface treatment with alum, which is known as one of the common adjuvants that activates inflammasome pathway. First, magnetite was prepared as a ferromagnetic particle and coated with alum. Alum-coated magnetite increased the expression of caspase-1, which is an activated indicator of inflammasome, in the culture of human monocyte cell (THP-1 cell). To evaluate the potential of the surface coated particles, the particles were subcutaneously injected to mice with a peptide vaccine. As a result, the antibody titer was increased by the surface coated particles as assessed by ELISA. Although a magnetic force has not yet applied in this study, the administration experiment to mice using magnetic force control is our next step. In conclusion, we modified the immune response to magnetite by coating the surface with alum. This can lead to a clinical application for vaccine therapy in future.

  16. Coated whey protein/alginate microparticles as oral controlled delivery systems for probiotic yeast.

    Science.gov (United States)

    Hébrard, Géraldine; Hoffart, Valérie; Beyssac, Eric; Cardot, Jean-Michel; Alric, Monique; Subirade, Muriel

    2010-01-01

    Viable Saccharomyces boulardii, used as a biotherapeutic agent, was encapsulated in food-grade whey protein isolate (WP) and alginate (ALG) microparticles, in order to protect and vehicle them in gastrointestinal environment. Yeast-loaded microparticles with a WP/ALG ratio of 62/38 were produced with high encapsulation efficiency (95%) using an extrusion/cold gelation method and coated with ALG or WP by a simple immersion method. Swelling, yeast survival, WP loss and yeast release in simulated gastric and intestinal fluids (SGF and SIF, pH 1.2 and 7.5) with and without their respective digestive enzymes (pepsin and pancreatin) were investigated. In SGF, ALG network shrinkage limited enzyme diffusion into the WP/ALG matrix. Coated and uncoated WP/ALG microparticles were resistant in SGF even with pepsin. Survival of yeast cells in microparticles was 40% compared to 10% for free yeast cells and was improved to 60% by coating. In SIF, yeast cell release followed coated microparticle swelling with a desirable delay. Coated WP/ALG microparticles appear to have potential as oral delivery systems for Saccharomyces boulardii or as encapsulation means for probiotic cells in pharmaceutical or food processing applications.

  17. [Silica-coated ethosome as a novel oral delivery system for enhanced oral bioavailability of curcumin].

    Science.gov (United States)

    Li, Chong; Deng, Li; Zhang, Yan; Su, Ting-Ting; Jiang, Yin; Chen, Zhang-Bao

    2012-11-01

    The aim of this study is to investigate the feasibility of silica-coated ethosome as a novel oral delivery system for the poorly water-soluble curcumin (as a model drug). The silica-coated ethosomes loading curcumin (CU-SE) were prepared by alcohol injection method with homogenization, followed by the precipitation of silica by sol-gel process. The physical and chemical features of CU-SEs, and curcumin release were determined in vitro. The pharmacodynamics and bioavailability measurements were sequentially performed. The mean diameter of CU-SE was (478.5 +/- 80.3) nm and the polydispersity index was 0.285 +/- 0.042, while the mean value of apparent drug entrapment efficiency was 80.77%. In vitro assays demonstrated that CU-SEs were significantly stable with improved release properties when compared with curcumin-loaded ethosomes (CU-ETs) without silica-coatings. The bioavailability of CU-SEs and CU-ETs was 11.86- and 5.25-fold higher, respectively, than that of curcumin suspensions (CU-SUs) in in vivo assays. The silica coatings significantly promoted the stability of ethosomes and CU-SEs exhibited 2.26-fold increase in bioavailablity relative to CU-ETs, indicating that the silica-coated ethosomes might be a potential approach for oral delivery of poorly water-soluble drugs especially the active ingredients of traditional Chinese medicine with improved bioavailability.

  18. Development and in vitro Evaluation of Enteric Coated Multiparticulate System for Resistant Tuberculosis.

    Science.gov (United States)

    Rahman, Md A; Ali, J

    2008-01-01

    The multiparticulate formulation of sodium para aminosalicylate for oral administration was developed by extrusion spheronization technique. Microcrystalline cellulose was used as filler in concentration of 14.4% w/w. Pellets were coated with Eudragit L 30 D-55 using fluidized bed processor. Different weight gains of acrylic polymer were applied onto the pellets and evaluated for in vitro dissolution behavior in 0.1 N HCl for two hours and then media was changed to phosphate buffer pH 6.8. A 60% w/w coating level of Eudragit L30 D 55 has produced the most acceptable results against the gastric attack. 3% Seal coat of HPMC E5 was also applied in order to protect the drug from migration into the Eudragit coat and film coat was applied in order to prevent aggregation of pellets in the dissolution media. Morphological characteristics of developed pellets were also investigated by scanning electron microscopy and found to be smooth and spherical. Developed system was found to be suitable for the delivery of Sod PAS in to intestinal region.

  19. Development and in vitro evaluation of enteric coated multiparticulate system for resistant tuberculosis

    Directory of Open Access Journals (Sweden)

    Rahman Md

    2008-01-01

    Full Text Available The multiparticulate formulation of sodium para aminosalicylate for oral administration was developed by extrusion spheronization technique. Microcrystalline cellulose was used as filler in concentration of 14.4% w/w. Pellets were coated with Eudragit L 30 D-55 using fluidized bed processor. Different weight gains of acrylic polymer were applied onto the pellets and evaluated for in vitro dissolution behavior in 0.1 N HCl for two hours and then media was changed to phosphate buffer pH 6.8. A 60% w/w coating level of Eudragit L30 D 55 has produced the most acceptable results against the gastric attack. 3% Seal coat of HPMC E5 was also applied in order to protect the drug from migration into the Eudragit coat and film coat was applied in order to prevent aggregation of pellets in the dissolution media. Morphological characteristics of developed pellets were also investigated by scanning electron microscopy and found to be smooth and spherical. Developed system was found to be suitable for the delivery of Sod PAS in to intestinal region.

  20. Coating Properties of WC-Ni Cold Spray Coating for the Application in Secondary Piping System of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, JeongWon; Kim, Seunghyun; Kim, Ji Hyun [UNIST, Ulsan (Korea, Republic of)

    2015-10-15

    As a result of FAC(flow accelerated corrosion), severe accidents, failure of carbon steel like a Mihama Unit-3 occurred. Chemical composition change of carbon steel or coating to inner surface is one of methods to improve corrosion properties. Among them, thermal spray coating is convenient solution to apply at industry. Powder is melted at blast furnace and ejected to substrate. After adhesion, substrate and coating layer is cooled down and coated layer protects steel from corrosion finally. However high thermal energy is transferred to substrate and coating layer so it leads high thermal residual stress in coating procedure. Besides, high temperature for melting powder makes unexpected chemical reaction of powder like an oxidation or carburization. Whereas, cold spray uses low temperature comparing with other thermal spray. Thermal energy is used for not melting powder but high kinetic energy of powder and plastic deformation during collision. Therefore, fuel such as oxygen-acetylene gas is not needed. It needs carrier gas, compressed air, nitrogen or helium, to increase kinetic energy of powder and move powder to substrate. Comparing cold spray with high velocity oxy fuel (HVOF), one of thermal spray, cold spray coating layer contains only WC and Co. One of other problem about WC is brittleness during coating. To improve deformability of WC, binder metal is added. For example, Co, Cr, Ni, Cu, Al, Fe or etc. Additionally, binder metal lowering melting temperature of composite powder increases coating properties. Among them, Co which is widely used as binder metal maintains mechanical properties like a hardness and improves corrosion properties. Therefore Co is not suitable for binder metal of WC coating. In contrast, Ni has better corrosion resistance to alkaline environment and makes lower melting temperature. Moreover, in a view of cold spray, FCC structure has better deformability than BCC or HCP, and BCC has lowest deformability. WC is BCC structure so it

  1. Influence of lithium coating on the optics of Doppler backscatter system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X. H.; Liu, A. D., E-mail: lad@ustc.edu.cn; Zhou, C.; Hu, J. Q.; Wang, M. Y.; Yu, C. X.; Liu, W. D.; Li, H.; Lan, T.; Xie, J. L. [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2015-10-15

    This paper presents the first investigation of the effect of lithium coating on the optics of Doppler backscattering. A liquid lithium limiter has been applied in the Experimental Advanced Superconducting Tokamak (EAST), and a Doppler backscattering has been installed in the EAST. A parabolic mirror and a flat mirror located in the vacuum vessel are polluted by lithium. An identical optical system of the Doppler backscattering is set up in laboratory. The power distributions of the emission beam after the two mirrors with and without lithium coating (cleaned before and after), are measured at three different distances under four incident frequencies. The results demonstrate that the influence of the lithium coating on the power distributions are very slight, and the Doppler backscattering can work normally under the dosage of lithium during the 2014 EAST campaign.

  2. Mechanisms governing the interfacial delamination of thermal barrier coating system with double ceramic layers

    Science.gov (United States)

    Xu, Rong; Fan, Xueling; Wang, T. J.

    2016-05-01

    A systematic study of factors affecting the interfacial delamination of thermal barrier coating system (TBCs) with double ceramic layers (DCL) is presented. Crack driving forces for delaminations at two weak interfaces are examined. The results show that a thicker outermost ceramic layer can induce dramatic increase in crack driving force and make the interface between two ceramic coatings become more prone to delamination. The behavior is shown to be more prominent in TBCs with stiffer outmost coating. The thickness ratio of two ceramic layers is an important parameter for controlling the failure mechanisms and determining the lifetime of DCL TBCs under inservice condition. By accounting for the influences of thickness ratio of two ceramic layers and interfacial fracture toughnesses of two involved interfaces, the fracture mechanism map of DCL TBCs has been constructed, in which different failure mechanisms are identified. The results quanlitatively agree with the aviliable experimental data.

  3. Electrically insulating coatings for V-Li self-cooled blanket in a fusion system

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Reed, C. B.; Uz, M.; Park, J. H.; Smith, D. L.

    2000-05-17

    The blanket system is one of the most important components in a fusion reactor because it has a major impact on both the economics and safety of fusion energy. The primary functions of the blanket in a deuterium/tritium-fueled fusion reactor are to convert the fusion energy into sensible heat and to breed tritium for the fuel cycle. The liquid-metal blanket concept requires an electrically insulating coating on the first-wall structural material to minimize the magnetohydrodynamic pressure drop that occurs during the flow of liquid metal in a magnetic field. Based on the thermodynamics of interactions between the coating and the liquid lithium on one side and the structural V-base alloy on the other side, several coating candidates are being examined to perform the insulating function over a wide range of temperatures and lithium chemistries.

  4. Availability of Tongue Diagnosis System for Assessing Tongue Coating Thickness in Patients with Functional Dyspepsia

    Directory of Open Access Journals (Sweden)

    Juyeon Kim

    2013-01-01

    Full Text Available Tongue diagnosis is an important procedure in traditional Korean medicine (TKM. In particular, tongue coating thickness (TCT is deemed to show the progression of the disease. However, conventional tongue diagnosis has limitations because of various external factors. Therefore, it is necessary to investigate the availability of tongue diagnosis system (TDS in the assessment of TCT. This study has been designed as a prospective clinical trial involving 60 patients with functional dyspepsia. Tongue images will be obtained by TDS twice with a 30 min interval. The system will measure the percentage of TCT and classify it as either no coating, thin coating, or thick coating according to the existing diagnostic criteria. After finishing the collection of 60 patients' tongue images, TCT on the images will be simultaneously evaluated by the conventional method to establish the gold standard for assessing TCT by 5 well-trained clinicians. The evaluation will be repeated by the same clinicians after 2 weeks, but the order of the images will be changed. This trial is expected to provide clinical evidence for the availability of TDS as a diagnostic tool and to contribute to the standardization of the diagnosis system used in TKM. This trial is registered with ClinicalTrials.gov NCT01864837.

  5. Analysis of long-term mechanical grooming on large-scale test panels coated with an antifouling and a fouling-release coating.

    Science.gov (United States)

    Hearin, John; Hunsucker, Kelli Z; Swain, Geoffrey; Stephens, Abraham; Gardner, Harrison; Lieberman, Kody; Harper, Michael

    2015-01-01

    Long-term grooming tests were conducted on two large-scale test panels, one coated with a fluorosilicone fouling-release (FR) coating, and one coated with a copper based ablative antifouling (AF) coating. Mechanical grooming was performed weekly or bi-weekly using a hand operated, electrically powered, rotating brush tool. The results indicate that weekly grooming was effective at removing loose or heavy biofilm settlement from both coatings, but could not prevent the permanent establishment of low-profile tenacious biofilms. Weekly grooming was very effective at preventing macrofouling establishment on the AF coating. The effectiveness of weekly grooming at preventing macrofouling establishment on the FR coating varied seasonally. The results suggest that frequent mechanical grooming is a viable method to reduce the fouling rating of ships' hulls with minimal impact to the coating. Frequent grooming could offer significant fuel savings while reducing hull cleaning frequencies and dry dock maintenance requirements.

  6. Application of a production line phosphorescence sensor coating system on a jet engine for surface temperature detection

    Science.gov (United States)

    Sollazzo, P. Y.; Feist, J. P.; Berthier, S.; Charnley, B.; Wells, J.; Heyes, A. L.

    2013-09-01

    Thermal Barrier Coatings (TBC) are used to reduce the working temperature of the high pressure turbine blade metal surface and hence permit engines to operate at higher temperatures/ efficiencies. A sensor TBC is an adaptation of existing TBCs to enhance their functionality, such that they become sensors and allow measurement of component temperatures. The sensing capability is introduced by embedding optically active materials into the TBC and by illuminating these coatings with excitation light phosphorescence can be observed. The phosphorescence carries temperature and structural information about the coating. This paper describes the first ever implementation of a sensor coating system on a full-scale jet engine. The system consists of three main components: industrially manufactured coatings, advanced remote detection optics with large stand-off distances and tailored control and readout software. The majority of coatings were based on yttrium stabilized zirconia doped with Dy and Eu, although other coatings were manufactured, too. Coatings were produced on a production line using atmospheric plasma spraying. An advanced optical system was designed, manufactured and operated permitting scanning of coated components using a wide acceptance angle. Successful measurements were taken from the nozzle guide vanes at the inlet to the turbine section and are reported in the paper.

  7. Advanced thermal barrier system bond coatings for use on nickel-, cobalt- and iron-base alloy substrates

    Science.gov (United States)

    Stecura, S.

    1986-01-01

    New and improved Ni-, Co-, and Fe-base bond coatings have been identified for the ZrO2-Y2O3 thermal barrier coatings to be used on Ni-, Co-, and Fe-base alloy substrates. These bond coatings were evaluated in a cyclic furnace between 1120 and 1175 C. It was found that MCrAlYb (where M = Ni, Co, or Fe) bond coating thermal barrier systems have significantly longer lives than MCrAlY bond coating thermal barrier systems. The longest life was obtained with the FeCrAlYb thermal barrier system followed by NiCrAlYb and CoCrAlYb thermal barrier systems in that order.

  8. Analysis and Alternate Selection of Nanopowder Modifiers to Improve a Special Protective Coating System

    Directory of Open Access Journals (Sweden)

    S. P. Bardakhanov

    2017-01-01

    Full Text Available This paper presents a practical approach for rational choice of silica nanopowders as modifiers to control and improve the performance of protective coating systems operating in harsh environmental conditions. The approach is based on the multiparameter analysis of nanoparticle reactivity of similar silica synthesized by using chemical and physical methods. The analysis indicates distinct adsorption centers due to the differences in the particles formation; the features of the formation and adsorption mechanisms lead to higher diffusion capacity of the nanoparticles, synthesized by physical methods, into a paint material and finally result in stronger chemical bonds between the system elements. The approach allows reducing the consumption of paint materials by 30% or more, at least 2-3 times increasing of the coating adhesion and hence the system life. Validity of the approach is illustrated through the data obtained from comparative modeling, factory testing, and practical use of modified systems.

  9. Effects of compound carboxylate-urea system on nano Ni-Cr/SiC composite coatings from trivalent chromium baths.

    Science.gov (United States)

    He, Xinkuai; Hou, Bailong; Cai, Youxing; Wu, Luye

    2013-03-01

    The effects of compound carboxylate-urea system on the nano Ni-Cr/SiC composite coatings from trivalent chromium baths have been investigated in ultrasonic field. These results indicated that the SiC and Cr contents and the thickness of the Ni-Cr/SiC composite coatings could be obviously improved by the compound carboxylate-urea system. The steady-state polarization curves showed that the hydrogen evolution reaction (HER) could be significantly inhibited by the compound carboxylate-urea system, which was benefit to increase the SiC and Cr contents and the thickness of the composite coatings. The cyclic voltammetry (CV) curves showed that both of the Cr(III) and Ni(II) cathodic polarization could be increased in the bath containing the compound carboxylate-urea system. Thus, a compact Ni-Cr/SiC composite coating could be obtained using this technique. The surface morphology of the Ni-Cr/SiC composite coatings checked with the scanning electron micrographs (SEM) showed that the surface smoothness could be also improved and the microcracks and pinholes could be decreased due to the presence of the compound carboxylate-urea system. The phase composition of the as-posited coating was measured by the X-ray diffraction. XRD data showed that the as-posited coating was Ni-Cr/SiC composite coating. The chemical composition of the coating was investigated by energy dispersive spectrum (EDS) analysis. The result showed the Ni-Cr/SiC composite coatings with 3.8 wt.% SiC and 24.68 wt.% Cr were obtained in this study, which had best corrosion resistance according to the results of the typical potentiodynamic polarization curves of the Ni-Cr/SiC composite coatings.

  10. TPB-coated Light Guides for Liquid Argon TPC Light Detection Systems

    CERN Document Server

    Ignarra, C M

    2013-01-01

    Light detection systems in Liquid Argon Time Projection Chambers (LArTPCs) require the detection of the 128 nm light produced during argon scintillation. Most detectors use Tetraphenyl Butadiene (TPB) to shift the wavelength of the light into a range visible to Photomultiplier Tubes (PMTs). These proceedings summarize characterizations of light-guides coated with a matrix of TPB in UV transmitting acrylic which are more compact than existing LArTPC light collection systems.

  11. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Angel Sanjurjo

    2006-06-01

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. In previous tests, we had frequently encountered problems with our steam generator that were exacerbated by the very low flow rates that we needed. During this period we installed a new computer-controlled system for injecting water into the steam generator that eliminated this problem. We also tested alloy coupons coated by using the improved procedures described in our last quarterly report. Most of these coatings were nitrided Ti and Ta coatings, either by themselves, or sometimes with barrier layers of Al and Si nitrides. The samples were tested for 300 h at 900 C in a gas stream designed to mimic the environment in the high temperature heat recovery unit (HTHRU). Three samples that showed least corrosion were exposed for an additional 100 h.

  12. AN AUTOMATIC MEASURING SYSTEM FOR PRINT QUALITY OF COATED INK-JET PAPER

    Institute of Scientific and Technical Information of China (English)

    JinsongTao; GangChen; MiaonanZhu; AiminTang; HongweiZhang

    2004-01-01

    An automatic visual measuring system designed for evaluating the print quality of coated ink-jet paper is presented. Based on the degree of wicking, feathering, strike-through and color-to-color bleeding, Ink-jet Print Quality Index (IPQI), which was calculated with Area Spread Ratio (ASR), Edge Raggedness (ER), and Roundness Deviation (RD) of the printed dots, was used to evaluate the print quality. An iterative repetition interpolation threshold segmentation algorithm was performed with the aid of magnifying glass, charge coupled device (CCD)camera, frame grabber, image software and computer. Seven kinds of coated glossy photo papers were tested with a constant ink and ink-jet printer, the optical print resolution of each kind was obtained and their performance was ranked. It was shown that the system can meet the requirements ofpapermakers and can provide an objective and quantitative method both for evaluating the print quality, determining the optical print resolution and optimizing the coating process for coated ink-jet paper.

  13. AN AUTOMATIC MEASURING SYSTEM FOR PRINT QUALITY OF COATED INK-JET PAPER

    Institute of Scientific and Technical Information of China (English)

    Jinsong Tao; Gang Chen; Miaonan Zhu; Aimin Tang; Hongwei Zhang

    2004-01-01

    An automatic visual measuring system designed for evaluating the print quality of coated ink-jet paper is presented. Based on the degree of wicking,feathering, strike-through and color-to-color bleeding, Ink-jet Print Quality Index (IPQI), which was calculated with Area Spread Ratio (ASR), Edge Raggedness (ER), and Roundness Deviation (RD) of the printed dots, was used to evaluate the print quality. An iterative repetition interpolation threshold segmentation algorithm was performed with the aid of magnifying glass, charge coupled device (CCD)camera, frame grabber, image software and computer. Seven kinds of coated glossy photo papers were tested with a constant ink and ink-jet printer,the optical print resolution of each kind was obtained and their performance was ranked. It was shown that the system can meet the requirements ofpapermakers and can provide an objective and quantitative method both for evaluating the print quality, determining the optical print resolution and optimizing the coating process for coated ink-jet paper.

  14. Coated particle fuel for radioisotope power systems (RPSs) and radioisotope heater units (RHUs)

    Science.gov (United States)

    Sholtis, Joseph A.; Lipinski, Ronald J.; El-Genk, Mohamed S.

    1999-01-01

    Coated particle fuel offers great promise for advanced radioisotope power systems (RPSs) and radioisotope heater units (RHUs) being pursued for future U.S. solar system exploration missions. Potential benefits of this fuel include improved design flexibility and materials compatibility, enhanced safety and performance, and reduced specific mass and volume. This paper describes and discusses coated particle fuel, with emphasis on its applicability, attributes, and potential benefits to future RPSs and RHUs. Additionally, this paper identifies further analyses and verification testing that should be conducted before a commitment is made to fully develop this fuel. Efforts to date indicate there is every reason to believe that the potential benefits of coated particle fuel to future RPSs and RHUs can be demonstrated with a modest, phased analytical and verification test effort. Thus, developmental risk appears minimal, while the potential benefits are substantial. If coated particle fuel is pursued and ultimately developed successfully, it could revolutionize the design and space use of future RPSs and RHUs.

  15. Characterization and refinement of carbide coating formation rates and dissolution kinetics in the Ta-C system

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Patrick James [Univ. of New Mexico, Albuquerque, NM (United States)

    1996-10-01

    The interaction between carbide coating formation rates and dissolution kinetics in the tantalum-carbon system was investigated. The research was driven by the need to characterize carbide coating formation rates. The characterization of the carbide coating formation rates was required to engineer an optimum processing scheme for the fabrication of the ultracorrosion-resistant composite, carbon-saturated tantalum. A packed-bed carburization process was successfully engineered and employed. The packed-bed carburization process produced consistent, predictable, and repeatable carbide coatings. A digital imaging analysis measurement process for accurate and consistent measurement of carbide coating thicknesses was developed. A process for removing the chemically stable and extremely hard tantalum-carbide coatings was also developed in this work.

  16. Hardface coating systems and methods for metal alloys and other materials for wear and corrosion resistant applications

    Energy Technology Data Exchange (ETDEWEB)

    Seals, Roland D.

    2015-08-18

    The present disclosure relates generally to hardface coating systems and methods for metal alloys and other materials for wear and corrosion resistant applications. More specifically, the present disclosure relates to hardface coatings that include a network of titanium monoboride (TiB) needles or whiskers in a matrix, which are formed from titanium (Ti) and titanium diboride (TiB.sub.2) precursors by reactions enabled by the inherent energy provided by the process heat associated with coating deposition and, optionally, coating post-heat treatment. These hardface coatings are pyrophoric, thereby generating further reaction energy internally, and may be applied in a functionally graded manner. The hardface coatings may be deposited in the presence of a number of fluxing agents, beta stabilizers, densification aids, diffusional aids, and multimode particle size distributions to further enhance their performance characteristics.

  17. Extraction of starch from hulled and hull-less barley with papain and aqueous sodium hydroxide

    OpenAIRE

    2013-01-01

    Starch was isolated from hulled (VJM 201) and hull-less (BL 134) barley with papain and aqueous sodium hydroxide treatments. For enzyme-assisted extraction, barley was steeped in water containing 0.2 % SO2 + 0.55 % lactic acid at 50° ± 2 °C for 4–5 h. The slurry was mixed with 0.4–2.0 g papain/kg barley and incubated at 50° ± 2 °C for 1–5 h. Aqueous sodium hydroxide (0.01–0.05 M) was added to the finely ground barley meal. The alkaline slurry was incubated at ambient temperature (25° ± 2 °C) ...

  18. 46 CFR 91.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery... hulls, boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels, the..., respecting material and inspection of hulls, boilers, and machinery, and the certificate of...

  19. 46 CFR 189.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery... inspection of hulls, boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels... chapter, respecting material and construction of hulls, boilers, and machinery, and certificate...

  20. Notes on aerodynamic forces on airship hulls

    Science.gov (United States)

    Tuckerman, L B

    1923-01-01

    For a first approximation the air flow around the airship hull is assumed to obey the laws of perfect (i.e. free from viscosity) incompressible fluid. The flow is further assumed to be free from vortices (or rotational motion of the fluid). These assumptions lead to very great simplifications of the formulae used but necessarily imply an imperfect picture of the actual conditions. The value of the results depends therefore upon the magnitude of the forces produced by the disturbances in the flow caused by viscosity with the consequent production of vortices in the fluid. If these are small in comparison with the forces due to the assumed irrotational perfect fluid flow the results will give a good picture of the actual conditions of an airship in flight.

  1. Wave induced extreme hull girder loads on containerships

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Pedersen, Preben Terndrup; Shi, Bill;

    2009-01-01

    , forward speed and hull flexibility. The vertical hull girder loads are evaluated for specific operational profiles. Firstly a quadratic strip theory is presented which can give separate predictions for the hogging and sagging bending moments and shear forces and for hull girder loads. Then this procedure...... is used as a base to derive semi-analytical formulas such that approximate wave load calculations can be performed by a simple spreadsheet program. Due to the few input parameters this procedure can be used to estimate the wave-induced bending moments at the conceptual design phase. Since the procedure...

  2. Pyrolysis of sunflower seed hulls for obtaining bio-oils.

    Science.gov (United States)

    Casoni, Andrés I; Bidegain, Maximiliano; Cubitto, María A; Curvetto, Nestor; Volpe, María A

    2015-02-01

    Bio-oils from pyrolysis of as received sunflower seed hulls (SSH), hulls previously washed with acid (SSHA) and hulls submitted to a mushroom enzymatic attack (BSSH) were analyzed. The concentration of lignin, hemicellulose and cellulose varied with the pre-treatment. The liquid corresponding to SSH presented a relatively high concentration of acetic acid and a high instability to storage. The bio-oil from SSHA showed a high concentration of furfural and an appreciable amount of levoglucosenone. Lignin was degraded upon enzymatic activity, for this reason BSSH led to the highest yield of bio-oil, with relative high concentration of acetic acid and stability to storage.

  3. Corn fiber hulls as a food additive or animal feed

    Science.gov (United States)

    Abbas, Charles; Beery, Kyle E.; Cecava, Michael J.; Doane, Perry H.

    2010-12-21

    The present invention provides a novel animal feed or food additive that may be made from thermochemically hydrolyzed, solvent-extracted corn fiber hulls. The animal feed or food additive may be made, for instance, by thermochemically treating corn fiber hulls to hydrolyze and solubilize the hemicellulose and starch present in the corn fiber hulls to oligosaccharides. The residue may be extracted with a solvent to separate the oil from the corn fiber, leaving a solid residue that may be prepared, for instance by aggolmerating, and sold as a food additive or an animal feed.

  4. Effects of coatings on storability of carrot under evaporative coolant system.

    Directory of Open Access Journals (Sweden)

    Adetunji Charles Oluwaseun

    2013-09-01

    Full Text Available Four different coatings were developed from the mucilage of Cactus and their effects were investigated on the quality and storability of carrot fruits. The four experimental coatings were: Pure mucilage extracts (ME, Mucilage extract mixed with 5ml glycerol (MEG, Mucilage extract mixed 5ml soy oil ( MESO, Mucilage extract mixed with 5ml olive oil(MEOO the addition of oil served as plasticizer. The following parameters were measured: weight loss, ascorbic acid content, pH, firmness and microbial qualities. Four hundred and eighty (480 carrot were arranged randomly into five treatments, the control (untreated and four coating treatments were stored for seven weeks under Evaporative Coolant System (ECS. Prior to storage, the carrot samples were surface sterilized using 100mg/L sodium hypochlorite. Results showed that Cactus mucilage was effective in extending the shelf-life of carrotwhen compared to untreated control in the following order: MESO>MEOO>MEG>ME>Control. Results revealed that coatings hindered the growth of microorganisms significantly

  5. Organic Coatings on Primitive Grains in IDPs: Implications for the Formation of Solar System Organic Matter

    Science.gov (United States)

    Flynn, G. J.; Wirick, S.; Keller, L. P.; Sandford, S.

    2009-12-01

    Chondritic, porous interplanetary dust particles (CP IDPs) are the most primitive samples of extraterrestrial material available for laboratory analysis [1]. These ~10 micron CP IDPs are unequilibrated aggregates of mostly submicron, anhy-drous grains of a diverse variety, including olivine, pyroxene, glass, and sulfide. We previously reported that CP IDPs contain a significant amount of organic matter, and concluded that parent body aqueous processing, which these IDPs never experienced, was not the mechanism that produced much of the pre-biotic organic matter of the early Solar System [2]. However, we were not able to establish either the time or mechanism of its production. The individual grains in these CP IDPs are coated by layers of carbonaceous material [3], typically ~100 nm thick, which holds the grains together. We have analyzed these grain coatings by X-ray Absorption Near-Edge Structure (XANES) spectroscopy using the Scanning Transmission X-Ray Microscope (STXM) on beamline X1A of the National Synchrotron Light Source. We have obtained C-XANES maps, using a 35 nm probe spot, of ultramicrotome sections from CP IDPs. Cluster analysis, which compares spectra from each pixel in the map and identifies groups of pixels exhibiting similar spectra [4], was used to analyze the data. Cluster analysis indicates most carbonaceous grain coatings have very similar C-XANES spectra, demonstrating that carbonaceous coatings on the individual grains in CP IDPs are organic, with the two strongest absorption features from C=C and C=O. This organic matter coats the individual grains, implying an assembly sequence beginning with grain formation, followed by the emplacement of the organic coating, and finally the assembly of the primitive dust particles. The organic grain coatings in the primitive CP IDPs appear to have formed prior to the aggregation of the most primitive dust particles currently available for laboratory analysis, indicating that these grain coatings are the

  6. Experimental and Numerical Analysis of Hull Girder Vibrations and Bow Impact of a Large Ship Sailing in Waves

    Directory of Open Access Journals (Sweden)

    Jialong Jiao

    2015-01-01

    Full Text Available It is of great importance to evaluate the hull structural vibrations response of large ships in extreme seas. Studies of hydroelastic response of an ultra large ship have been conducted with comparative verification between experimental and numerical methods in order to estimate the wave loads response considering hull vibration and water impact. A segmented self-propelling model with steel backbone system was elaborately designed and the experiments were performed in a tank. Time domain numerical simulations of the ship were carried out by using three-dimensional nonlinear hydroelasticity theory. The results from the computational analyses have been correlated with those from model tests.

  7. Thin-Walled Beam Theories and Their Applications in the Torsional Strength Analysis of Ship Hulls.

    Science.gov (United States)

    1987-01-01

    numerous deep web frames and transverse bulkheads. The system has been utilized in a study of a frigate under an assumed torsional/flexural load, the...transverse bulkheads and r deep web frames. Figure 18 indicates that, despite the poor agreement in twist angle, the axial stress results compare quite...under torsional loads. This will be the case for a typical warship hull, because of the large number of deep web frames and transverse bulkheads. The

  8. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Jordi Perez; Marc Hornbostel; Kai-Hung Lau; Angel Sanjurjo

    2007-05-31

    Advanced electric power generation systems use a coal gasifier to convert coal to a gas rich in fuels such as H{sub 2} and CO. The gas stream contains impurities such as H{sub 2}S and HCl, which attack metal components of the coal gas train, causing plant downtime and increasing the cost of power generation. Corrosion-resistant coatings would improve plant availability and decrease maintenance costs, thus allowing the environmentally superior integrated-gasification-combined-cycle (IGCC) plants to be more competitive with standard power-generation technologies. Heat-exchangers, particle filters, turbines, and other components in the IGCC system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low cost alloy will improve is resistance to such sulfidation attack and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. The Fe- and Ni-based high-temperature alloys are susceptible to sulfidation attack unless they are fortified with high levels of Cr, Al, and Si. To impart corrosion resistance, these elements need not be in the bulk of the alloy and need only be present at the surface layers. In this study, the use of corrosion-resistant coatings on low alloy steels was investigated for use as high-temperature components in IGCC systems. The coatings were deposited using SRI's fluidized-bed reactor chemical vapor deposition technique. Diffusion coatings of Cr and Al were deposited by this method on to dense and porous, low alloy stainless steel substrates. Bench-scale exposure tests at 900 C with a simulated coal gas stream containing 1.7% H{sub 2}S showed that the low alloy steels such SS405 and SS409 coated with

  9. Shuttle active thermal control system development testing. Volume 7: Improved radiator coating adhesive tests

    Science.gov (United States)

    Reed, M. W.

    1973-01-01

    Silver/Teflon thermal control coatings have been tested on a modular radiator system projected for use on the space shuttle. Seven candidate adhesives have been evaluated in a thermal vacuum test on radiator panels similar to the anticipated flight hardware configuration. Several classes of adhesives based on polyester, silicone, and urethane resin systems were tested. These included contact adhesives, heat cured adhesives, heat and pressure cured adhesives, pressure sensitive adhesives, and two part paint on or spray on adhesives. The coatings attached with four of the adhesives, two silicones and two urethanes, had no changes develop during the thermal vacuum test. The two silicone adhesives, both of which were applied to the silver/Teflon as transfer laminates to form a tape, offered the most promise based on application process and thermal performance. Each of the successful silicone adhesives required a heat and pressure cure to adhere during the cryogenic temperature excursion of the thermal-vacuum test.

  10. Characterization of Coated Sand Cores from Two Different Binder Systems for Grey Iron Castings

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Tiedje, Niels Skat; Poulsen, Thomas

    Expansion defects on the surface of the castings include sand burn-in, metal penetration and/or veining, finning or scab. Veining or finning and metal penetration are of interest. These defects are associated with silica sand and result from the penetration of liquid metal into cracks formed during...... differential expansion of the core during heating. The rapid expansion of silica sand up to 600 oC and especially at 573 oC, where the α – β phase transformation occurs, is the cause of stresses in the core system. These stresses cause crack formation and metal melt flows into these cracks causing finning...... or veining and metal penetration defects. The use of refractory coatings on cores is fundamental to obtaining acceptable casting surface quality and is used on resin bonded cores in production foundries. In this study new sol gel-coated sand cores made from coldbox and furan binder systems were investigated...

  11. Effect of Nitrogen on Hull Traits and Its Causes in Yangdao6

    Institute of Scientific and Technical Information of China (English)

    YANG Lian-xin; WANG Yu-long; DONG Gui-chun; HUANG Jian-yi; ZHANG Ya-jie; CAI Hui-rong

    2002-01-01

    The experiments were carried out under solution and pot cultural conditions with rice Yangdao6. Effect of nitrogen on hull size, weight and plumpness and its relationship with plant nutrition were analysed. On comparison with no fertilization, low N application concentration from transplanting to heading, or employing basal fertilizer or tiller promoting one would result in increment of hull size and weight,while raising N application concentration from transplanting to heading or employing excessive spike fertilizer would result in smaller, lighter hull and poorer hull plumpness. The more amount of nitrogen applied, the more hull development would be inhibited. Top dressing at heading would facilitate hull substance accumulation, but its effect on hull size was small. The variation of hull traits differed in the following order: hull weight > hull weight per unit area > hull area > hull length > hull width. Hull traits were highly significantly correlated to the nitrogen content of plant at heading, with correlation coefficient from - 0. 8684* * to- 0.9336 * *, and positively correlated to the contents of soluble sugar and starch at heading, with correlation coefficient of 0.6660NS - 0.9501 * *. Improving hull characters would be beneficial to substance accumulation of grain, thus improving grain weight considerably(r = 0.6388 * -0.9574 * * ).

  12. "Keisri hull" kui müstiline fantasy / Siimon Prii

    Index Scriptorium Estoniae

    Prii, Siimon

    2006-01-01

    30. sept. Ugalas esietendunud Jaan Krossi "Keisri hull" (autoridramatiseering), lavastajad Jaak Allik ja Peeter Tammearu. Kunstnik on Jaanus Laagriküll ja muusikaline kujundaja Peeter Konovalov. Peaosas Peeter Tammearu

  13. "Keisri hull" kui müstiline fantasy / Siimon Prii

    Index Scriptorium Estoniae

    Prii, Siimon

    2006-01-01

    30. sept. Ugalas esietendunud Jaan Krossi "Keisri hull" (autoridramatiseering), lavastajad Jaak Allik ja Peeter Tammearu. Kunstnik on Jaanus Laagriküll ja muusikaline kujundaja Peeter Konovalov. Peaosas Peeter Tammearu

  14. Efficient protocols for point-convex hull inclusion decision problems

    Directory of Open Access Journals (Sweden)

    Yun Ye

    2010-05-01

    Full Text Available Secure Multi-party Computation (SMC is dedicated to solve trust problems in cooperative computing with each participant’s private data. Privacy Preserving Computational Geometry (PPCG is a special area in SMC and being widely researched. In the real world, PPCG theories can be found being used in various occasions such as military cooperation, commercial competitions and so on. Point-convex hull inclusion problem is a practical case in PPCG and has its profound values. This paper firstly investigates the point inclusion problem with static convex hull, and then marches on to the cases of active convex hull, including the parallel moving and rotating ones. To solve the problems above, we propose a secure protocol to determine the relative position of a private point and a private convex hull in the first place. Compared with previous solutions, our protocols perform better in efficiency, especially when the number of the convex hull’s point is large.

  15. Hull shape optimization for autonomous underwater vehicles using CFD

    Directory of Open Access Journals (Sweden)

    Ting Gao

    2016-01-01

    Full Text Available Drag estimation and shape optimization of autonomous underwater vehicle (AUV hulls are critical to energy utilization and endurance improvement. In the present work, a shape optimization platform composed of several commercial software packages is presented. Computational accuracy, efficiency and robustness were carefully considered and balanced. Comparisons between experiments and computational fluid dynamics (CFD were conducted to prove that a two-dimensional (2D unstructured mesh, a standard wall function and adaptive mesh refinement could greatly improve efficiency as well as guarantee accuracy. Details of the optimization platform were then introduced. A comparison of optimizers indicates that the multi-island genetic algorithm (MIGA obtains a better hull shape than particle swarm optimization (PSO, despite being a little more time consuming. The optimized hull shape under general volume requirement could provide reference for AUV hull design. Specific requirements based on optimization testify of the platform’s robustness.

  16. Computing Hulls And Centerpoints In Positive Definite Space

    CERN Document Server

    Fletcher, P Thomas; Phillips, Jeff M; Venkatasubramanian, Suresh

    2009-01-01

    In this paper, we present algorithms for computing approximate hulls and centerpoints for collections of matrices in positive definite space. There are many applications where the data under consideration, rather than being points in a Euclidean space, are positive definite (p.d.) matrices. These applications include diffusion tensor imaging in the brain, elasticity analysis in mechanical engineering, and the theory of kernel maps in machine learning. Our work centers around the notion of a horoball: the limit of a ball fixed at one point whose radius goes to infinity. Horoballs possess many (though not all) of the properties of halfspaces; in particular, they lack a strong separation theorem where two horoballs can completely partition the space. In spite of this, we show that we can compute an approximate "horoball hull" that strictly contains the actual convex hull. This approximate hull also preserves geodesic extents, which is a result of independent value: an immediate corollary is that we can approxima...

  17. Pretreatment of rice hulls by ionic liquid dissolution.

    Science.gov (United States)

    Lynam, Joan G; Reza, M Toufiq; Vasquez, Victor R; Coronella, Charles J

    2012-06-01

    As a highly available waste product, rice hulls could be a starting block in replacing liquid fossil fuels. However, their silica covering can make further use difficult. This preliminary study investigates effects of dissolving rice hulls in the ionic liquids 1-ethyl-3-methylimidazolium acetate (EMIM Ac), 1-hexyl-3-methylimidazolium chloride, (HMIM Cl), and 1-allyl-3-methylimidazolium chloride (AMIM Cl), and what lignocellulosic components can be precipitated from the used ionic liquid with water and ethanol. EMIM Ac dissolution at 110 °C for 8 h was found to completely remove lignin from rice hulls, while ethanol was capable of precipitating lignin out of the used EMIM Ac. With 8h dissolution at 110 °C using HMIM Cl, approximately 20% of the cellulose in the rice hull sample can be precipitated out using water as co-solvent, while more than 60% of the hemicellulose can be precipitated with ethanol.

  18. Final Report on Portable Laser Coating Removal Systems Field Demonstrations and Testing

    Science.gov (United States)

    Rothgeb, Matthew J.; McLaughlin, Russell L.

    2008-01-01

    Processes currently used throughout the National Aeronautics and Space Administration (NASA) to remove corrosion and coatings from structures, ground service equipment and small components results in waste streams consisting of toxic chemicals, spent media blast materials, and waste water. When chemicals are used in these processes they are typically high in volatile organic compounds (VOC) and are considered hazardous air pollutants (HAP). When blast media is used, the volume of hazardous waste generated is increased significantly. Many of the coatings historically used within NASA contain toxic metals such as hexavalent chromium, and lead. These materials are highly regulated and restrictions on worker exposure continue to increase. Most recently the EPA reduced the permissible exposure limit (PEL) for hexavalent chromium. The new standard lowers OSHA's PEL for hexavalent chromium from 52 to 5 micrograms of Cr(V1) per cubic meter of air as an 8-hour time-weighted average. Hexavalent chromium is found in the pretreatment and primer coatings used within the Shuttle Program. In response to the need to continue to protect assets within the agency and the growing concern over these new regulations, NASA is researching different ways to continue the required maintenance of both facility and flight equipment in a safe, efficient and environmentally preferable manner. The use of laser energy to remove prepare surfaces for a variety of processes, such as corrosion and coating removal, weld preparation and non destructive evaluation is a relatively new technology that has shown itself to be environmentally preferable and in many cases less labor intensive than currently used removal methods. The development of a Portable Laser Coating Removal System (PLCRS) started as the goal of a Joint Group on Pollution Prevention (JG-PP) project, led by the Air Force, where several types of lasers in several configurations were thoroughly evaluated. Following this project, NASA decided

  19. Hydrodynamic modeling of semi-planing hulls with air cavities

    Directory of Open Access Journals (Sweden)

    Konstantin I. Matveev

    2015-05-01

    Full Text Available High-speed heavy loaded monohull ships can benefit from application of drag-reducing air cavities under stepped hull bottoms. The subject of this paper is the steady hydrodynamic modeling of semi-planing air-cavity hulls. The current method is based on a linearized potential-flow theory for surface flows. The mathematical model description and parametric calculation results for a selected configuration with pressurized and open air cavities are presented.

  20. Impact of Cardiovascular Health on Hearing: Interview with Ray Hull

    Science.gov (United States)

    Montgomery, Judy K.

    2006-01-01

    Do you belong to a sports club or gym? Do you like to work out, play tennis, swim, or run regularly? If so, you are also improving your hearing health. I did not learn this from a sports column; I learned it from interviewing Ray Hull. Dr. Raymond H. Hull, PhD, is a professor of communication sciences and disorders, audiology, and director of the…

  1. Microstructure Evolution and Durability of Advanced Environmental Barrier Coating Systems for SiC/SiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming; Evans, Laura J.; McCue, Terry R.; Harder, Bryan

    2016-01-01

    Environmental barrier coated SiC-SiC ceramic matrix composites (CMCs) systems will play a crucial role in next generation turbine engines for hot-section component applications because of their ability to significantly increase engine operating temperatures with improved efficiency, reduce engine weight and cooling requirements. Advanced HfO2 and rare earth silicate environmental barrier coatings (EBCs), along with multicomponent hafnium and rare earth silicide EBC bond coats have been developed. The coating degradation mechanisms in the laboratory simulated engine thermal cycling, and fatigue-creep operating environments are also being investigated. This paper will focus on the microstructural and compositional evolutions of an advanced environmental barrier coating system on a SiC-SiC CMC substrate during the high temperature simulated durability tests, by using a Field Emission Gun Scanning Electron Microscopy, Energy Dispersive Spectroscopy (EDS) and Wavelength Dispersive Spectroscopy (WDS). The effects of Calcium-Magnesium-Alumino-Silicate (CMAS) from road sand or volcano-ash deposits on the degradation mechanisms of the environmental barrier coating systems will also be discussed. The detailed analysis results help understand the EBC-CMC system performance, aiming at the durability improvements to achieve more robust, prime-reliant environmental barrier coatings.

  2. Preconditioning 2D Integer Data for Fast Convex Hull Computations.

    Directory of Open Access Journals (Sweden)

    José Oswaldo Cadenas

    Full Text Available In order to accelerate computing the convex hull on a set of n points, a heuristic procedure is often applied to reduce the number of points to a set of s points, s ≤ n, which also contains the same hull. We present an algorithm to precondition 2D data with integer coordinates bounded by a box of size p × q before building a 2D convex hull, with three distinct advantages. First, we prove that under the condition min(p, q ≤ n the algorithm executes in time within O(n; second, no explicit sorting of data is required; and third, the reduced set of s points forms a simple polygonal chain and thus can be directly pipelined into an O(n time convex hull algorithm. This paper empirically evaluates and quantifies the speed up gained by preconditioning a set of points by a method based on the proposed algorithm before using common convex hull algorithms to build the final hull. A speedup factor of at least four is consistently found from experiments on various datasets when the condition min(p, q ≤ n holds; the smaller the ratio min(p, q/n is in the dataset, the greater the speedup factor achieved.

  3. Grene and Hull on types and typological thinking in biology.

    Science.gov (United States)

    Honenberger, Phillip

    2015-04-01

    Marjorie Grene (1910-2009) and David Hull (1935-2010) were among the most influential voices in late twentieth-century philosophy of biology. But, as Grene and Hull pointed out in published discussions of one another's work over the course of nearly forty years, they disagreed strongly on fundamental issues. Among these contested issues is the role of what is sometimes called "typology" and "typological thinking" in biology. In regard to taxonomy and the species problem, Hull joined Ernst Mayr's construal of typological thinking as a backward relic of pre-Darwinian science that should be overcome. Grene, however, treated the suspicion of typological thinking that characterized Hull's views, as well as those of other architects of the New Evolutionary Synthesis, as itself suspicious and even unsustainable. In this paper I review three debates between Grene and Hull bearing on the question of the validity of so-called typological thinking in biology: (1) a debate about the dispensability of concepts of "type" within evolutionary theory, paleontology, and taxonomy; (2) a debate about whether species can be adequately understood as individuals, and thereby independently of those forms of thinking Hull and Mayr had construed as "typological"; and (3) a debate about the prospects of a biologically informed theory of human nature.

  4. Preconditioning 2D Integer Data for Fast Convex Hull Computations.

    Science.gov (United States)

    Cadenas, José Oswaldo; Megson, Graham M; Luengo Hendriks, Cris L

    2016-01-01

    In order to accelerate computing the convex hull on a set of n points, a heuristic procedure is often applied to reduce the number of points to a set of s points, s ≤ n, which also contains the same hull. We present an algorithm to precondition 2D data with integer coordinates bounded by a box of size p × q before building a 2D convex hull, with three distinct advantages. First, we prove that under the condition min(p, q) ≤ n the algorithm executes in time within O(n); second, no explicit sorting of data is required; and third, the reduced set of s points forms a simple polygonal chain and thus can be directly pipelined into an O(n) time convex hull algorithm. This paper empirically evaluates and quantifies the speed up gained by preconditioning a set of points by a method based on the proposed algorithm before using common convex hull algorithms to build the final hull. A speedup factor of at least four is consistently found from experiments on various datasets when the condition min(p, q) ≤ n holds; the smaller the ratio min(p, q)/n is in the dataset, the greater the speedup factor achieved.

  5. Long-Term Anti-Corrosion Performance of a Conducting Polymer-Based Coating System for Steels

    Science.gov (United States)

    Pan, Tongyan; Yu, Qifeng

    2016-06-01

    The long-term durability of a two-layer coating system was evaluated by two accelerated corrosion tests, i.e., the ASTM B117 Salt spray test and the ASTM D5894 Cyclic salt fog/UV exposure test, and a series of surface analyses. The coating system was developed for protecting structural steels from corrosion, including a functional primer made of intrinsically conducting polymer (ICP) and a protective topcoat. The standard pull-off test per ASTM D4541 was employed for characterizing the adhesion of the coating systems to substrate, aided by visual examination of the surface deterioration of the samples. The ICP-based systems demonstrated superior long-term anti-corrosion capacity when a polyurethane topcoat is used. The ICP-based primer made of a waterborne epoxy gave poorer anti-corrosion performance than the ICP-based primer made of regular non-waterborne epoxy, which can be attributed to the lower adhesion the waterborne epoxy demonstrated to the substrate surface. The zinc-rich control systems showed good anti-corrosion durability; however, they may produce excessive oxidative products of zinc to cause coating delamination. Based on the test results, the two-layer coating system consisting of an ICP-based primer and a polyurethane topcoat outperforms the conventional zinc-rich coating systems for corrosion protection of steels.

  6. Stress-strain state in "coating-substrate" system after coating stability loss induced by impact of thermal stresses

    Science.gov (United States)

    Lyukshin, P. A.; Bochkareva, S. A.; Grishaeva, N. Yu.; Lyukshin, B. A.; Matolygina, N. Yu.; Panin, S. V.

    2016-11-01

    Thermal barrier coatings (TBC) are aimed at protection of machine parts working under extremely high temperatures. One of the major problems at their exploitation is related to delamination of the coating from the substrate. In this concern, investigation of the patterns and evolution of the stress-strain state (SSS) at their interface is of particular interest. The main reasons of the delamination are associated with the distinction of thermo-physical properties (first of all, thermal expansion coefficient) of the interfaced material, as well as by the difference in heating conditions (heat supply and abstraction). The latter is of particular importance when the transient regimes take place under the heat impact, i.e. the TBC becomes rapidly heated, while the substrate has much lower temperature. In order to analyze and simulate the processes that give rise to the delamination, a number of problems is to be solved. At the first stage, the temperature variation induced by the thermal impact both in the coating and the substrate is to be determined. At the second stage, the distribution of the Stress Strain State (SSS) in the coating and the substrate are to be found. Based on the values of the calculated stresses, the stability loss patterns of the coating might be revealed. In doing so, the latter is regarded as a plate rested on Winkler elastic foundation. By defining the plate deflections in concern of its interaction with the substrate, the distribution of the SSS parameters at the contact surface can be found. Finally, the conditions to determine the TBC delamination from the substrate are estimated.

  7. Pyrolysis kinetics of raw and hydrothermally carbonized Karanj (Pongamia pinnata) fruit hulls via thermogravimetric analysis.

    Science.gov (United States)

    Islam, Md Azharul; Asif, M; Hameed, B H

    2015-03-01

    The pyrolysis of karanj fruit hulls (KFH) and karanj fruit hull hydrothermal carbonization (KFH-HTC) hydrochar was thermogravimetrically investigated under a nitrogen environment at 5 °C/min, 10 °C/min, and 20 °C/min. The pyrolysis decomposition of KFH biomass was faster than that of KFH-HTC hydrochar because of the high volatility and fixed carbon of KFH biomass. Weight loss percentage was also affected by the heating rates. The kinetic data were evaluated with the Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa methods. The activation energy values obtained with these two methods were 61.06 and 68.53 kJ/mol for KFH biomass and 130.49 and 135.87 kJ/mol for KFH-HTC hydrochar, respectively. The analysis of kinetic process mechanisms was verified with the Coats-Redfern method. KFH-HTC hydrochar may play a potential role in transforming biomass to energy-rich feedstock for thermochemical applications because of its high heating value, high fixed carbon, and low ash and sulfur contents.

  8. Evaluation of the biological activity of sunflower hull extracts

    Energy Technology Data Exchange (ETDEWEB)

    Taha, F. S.; Wagdy, S. M.; Hassanein, M. M. M.; Hamed, S. F.

    2012-11-01

    This work was planned with the aim of adding value to sunflower seed hulls, a waste product of the oil industry by preparing a sunflower hull phenolic extract rich in chlorogenic acid (CGA). In order to fulfill this goal, the optimization for the extraction of a phenolic extract from the hulls was investigated. The parameters studied were: type of solvent, solvent to water ratio and hull to solvent ratio. In addition, the solvent mixtures were also studied. The resulting phenolic extracts were evaluated for their biological activities. This included phenolic content determination, evaluation of the antioxidant and antimicrobial activities. Chlorogenic acid was determined in two chosen hull extracts using the UV spectrophotometric method and HPLC analysis. The anti carcinogenic activity of the two chosen extracts was tested on seven different cell line carcinomas. The results revealed that all the phenolic extracts of sunflower hull studied contain between 190-312.5 mg phenolics/ 100 g hulls. The highest phenolic extraction was achieved with 80% methanol (1:30, hull to solvent, w/v ratio) and methanol to ethanol to water (7:7:6 v/v/v) mixture with values of 312.5 and 306.5 mg phenolics/100 g hulls, respectively. The free radical scavenging activity and antioxidant activity of all the samples ranged from 33.6-72.6%. The highest antioxidant activity and free radical scavenging activity were achieved by the same extracts that possessed the highest phenolic content, namely methanol to ethanol to water extract and 80% methanol with values 71.8 and 72.6%, 68.2 and 70.9% respectively, compared to 77.9 and 76.9% respectively for TBHQ. All the phenolic extracts possessed antimicrobial activity but to different levels against different pathogenic bacteria. The two chosen extracts also possessed anti carcinogenic activity, which differed among varying cell line carcinomas. The HPLC analysis indicated that chlorogenic acid was the main phenolic acid in the extract. Thus it can

  9. Flip to Regular Triangulation and Convex Hull.

    Science.gov (United States)

    Gao, Mingcen; Cao, Thanh-Tung; Tan, Tiow-Seng

    2017-02-01

    Flip is a simple and local operation to transform one triangulation to another. It makes changes only to some neighboring simplices, without considering any attribute or configuration global in nature to the triangulation. Thanks to this characteristic, several flips can be independently applied to different small, non-overlapping regions of one triangulation. Such operation is favored when designing algorithms for data-parallel, massively multithreaded hardware, such as the GPU. However, most existing flip algorithms are designed to be executed sequentially, and usually need some restrictions on the execution order of flips, making them hard to be adapted to parallel computation. In this paper, we present an in depth study of flip algorithms in low dimensions, with the emphasis on the flexibility of their execution order. In particular, we propose a series of provably correct flip algorithms for regular triangulation and convex hull in 2D and 3D, with implementations for both CPUs and GPUs. Our experiment shows that our GPU implementation for constructing these structures from a given point set achieves up to two orders of magnitude of speedup over other popular single-threaded CPU implementation of existing algorithms.

  10. Sustainable design and manufacturing of multifunctional polymer nanocomposite coatings: A multiscale systems approach

    Science.gov (United States)

    Xiao, Jie

    Polymer nanocomposites have a great potential to be a dominant coating material in a wide range of applications in the automotive, aerospace, ship-making, construction, and pharmaceutical industries. However, how to realize design sustainability of this type of nanostructured materials and how to ensure the true optimality of the product quality and process performance in coating manufacturing remain as a mountaintop area. The major challenges arise from the intrinsic multiscale nature of the material-process-product system and the need to manipulate the high levels of complexity and uncertainty in design and manufacturing processes. This research centers on the development of a comprehensive multiscale computational methodology and a computer-aided tool set that can facilitate multifunctional nanocoating design and application from novel function envisioning and idea refinement, to knowledge discovery and design solution derivation, and further to performance testing in industrial applications and life cycle analysis. The principal idea is to achieve exceptional system performance through concurrent characterization and optimization of materials, product and associated manufacturing processes covering a wide range of length and time scales. Multiscale modeling and simulation techniques ranging from microscopic molecular modeling to classical continuum modeling are seamlessly coupled. The tight integration of different methods and theories at individual scales allows the prediction of macroscopic coating performance from the fundamental molecular behavior. Goal-oriented design is also pursued by integrating additional methods for bio-inspired dynamic optimization and computational task management that can be implemented in a hierarchical computing architecture. Furthermore, multiscale systems methodologies are developed to achieve the best possible material application towards sustainable manufacturing. Automotive coating manufacturing, that involves paint spay and

  11. Performance of Hull-Detection Algorithms For Proton Computed Tomography Reconstruction

    CERN Document Server

    Schultze, Blake; Censor, Yair; Schulte, Reinhard; Schubert, Keith Evan

    2014-01-01

    Proton computed tomography (pCT) is a novel imaging modality developed for patients receiving proton radiation therapy. The purpose of this work was to investigate hull-detection algorithms used for preconditioning of the large and sparse linear system of equations that needs to be solved for pCT image reconstruction. The hull-detection algorithms investigated here included silhouette/space carving (SC), modified silhouette/space carving (MSC), and space modeling (SM). Each was compared to the cone-beam version of filtered backprojection (FBP) used for hull-detection. Data for testing these algorithms included simulated data sets of a digital head phantom and an experimental data set of a pediatric head phantom obtained with a pCT scanner prototype at Loma Linda University Medical Center. SC was the fastest algorithm, exceeding the speed of FBP by more than 100 times. FBP was most sensitive to the presence of noise. Ongoing work will focus on optimizing threshold parameters in order to define a fast and effic...

  12. Fluid dynamic interface between hull and hydrofoil; Sentai to suichuyoku no ryutai rikigakuteki kansho ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Kataoka, K.; Ando, J.; Nakatake, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-04-10

    For the high-speed ship with hydrofoil, it is important to grasp the mutual interference between its hydrofoil and hull. In this study, effects of the state of hydrofoils and velocity on the hull were fluid-dynamically investigated through the numerical calculation by means of Rankine source method using a Wigley model with two hydrofoils. Before considering the model with hydrofoils, the attitude change of a hull without hydrofoils during traveling in high-speed was examined. For the high-speed ship, various measuring systems have been conceived due to the large change in its attitude. The Wigley model has been used for the numerical calculation when considering the attitude change in the medium- and low-speed regions. In this study, resistance tests without constraining the sinkage and trim were conducted using a Wigley model in the high-speed region around Fn=1.0, which have not been usually conducted. The attitude changes were compared with the numerical calculation results by the Rankine source method. The wave making resistance and attitude change of the Wigley model with hydrofoils were also calculated. 12 refs., 10 figs.

  13. Mathematical model of small water-plane area twin-hull and application in marine simulator

    Science.gov (United States)

    Zhang, Xiufeng; Lyu, Zhenwang; Yin, Yong; Jin, Yicheng

    2013-09-01

    Small water-plane area twin-hull (SWATH) has drawn the attention of many researchers due to its good sea-keeping ability. In this paper, MMG's idea of separation was used to perform SWATH movement modeling and simulation; respectively the forces and moment of SWATH were divided into bare hull, propeller, rudder at the fluid hydrodynamics, etc. Wake coefficient at the propellers which reduces thrust coefficient, and rudder mutual interference forces among the hull and propeller, for the calculation of SWATH, were all considered. The fourth-order Runge-Kutta method of integration was used by solving differential equations, in order to get SWATH's movement states. As an example, a turning test at full speed and full starboard rudder of `Seagull' craft is shown. The simulation results show the SWATH's regular pattern and trend of motion. It verifies the correctness of the mathematical model of the turning movement. The SWATH's mathematical model is applied to marine simulator in order to train the pilots or seamen, or safety assessment for ocean engineering project. Lastly, the full mission navigation simulating system (FMNSS) was determined to be a successful virtual reality technology application sample in the field of navigation simulation.

  14. Biosecurity risks associated with in-water and shore-based marine vessel hull cleaning operations.

    Science.gov (United States)

    Woods, Chris M C; Floerl, Oliver; Jones, Liz

    2012-07-01

    The removal of biofouling from vessels during hull cleaning can pose a biosecurity threat if viable, non-indigenous organisms are released into the aquatic environment. However, the effect of cleaning on biofouling organism viability in different types of cleaning operations has been poorly studied. We compared the effects of hull cleaning on biofouling organisms removed from 36 marine vessels during in-water (without capture of cleaning waste) and shore-based (with capture, and treatment of cleaning waste) cleaning. In-water cleaning resulted in higher proportions of viable biofouling organisms surviving cleaning (62.3 ± 7.1% of all organisms examined) compared to dry dock (37.8 ± 8.6%) and haul-out (20.1 ± 5.3%) operations. For shore-based facilities with effluent treatment systems, concentrations of organisms and/or their propagules in cleaning effluent was reduced by ≥ 98.5% compared to initial hydro-blast effluent concentrations. These results can be used in guidance for hull cleaning operations to minimize associated biosecurity risk. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Jordi Perez-Mariano; Angel Sanjurjo

    2005-03-15

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high-temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. During this period, we conducted two 300-hour tests. In the first test, we exposed samples at 900 C under conditions simulating the high-temperature heat recovery unit (HTHRU). The second test was at 370 C, corresponding to the filter units following the HTHRU. The tests were showed the resilience of silicon nitride as a coating component, and the new coating procedures better penetrated the pores in sintered metal filter samples. Finally, we also received samples that were exposed in the Wabash River plant. Unfortunately, all these samples, that were prepared last year, were severely eroded and/or corroded.

  16. Effect of annealing on phase sequence and their composition in the Pt-coated Mo system

    Energy Technology Data Exchange (ETDEWEB)

    Khumalo, Z.M., E-mail: zakhele@tlabs.ac.za [Department of Physics, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Topić, M. [Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Comrie, C.M. [Department of Physics, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Blumenthal, M. [Department of Physics, University of Cape Town, Private Bag X3, Rondebosch 7701 (South Africa); Pineda-Vargas, C.A.; Bucher, R. [Materials Research Department, National Research Foundation, iThemba LABS, P.O. Box 722, Somerset West (South Africa); Kisslinger, K. [Center for Functional Nanomaterials, Brookhaven National Laboratory, P.O. Box 5000, Upton, NY USA (United States)

    2014-11-01

    Highlights: • Platinum coatings were prepared using electron beam evaporator. • The phase analysis revealed the presence of the MoPt{sub 2} and MoPt. • At low annealing time, the MoPt{sub 2} phase appeared to have more Pt content. • The MoPt{sub 2} phase disappeared as the annealing time increases. • It is believed that the MoPt phase was growing at the expense of the MoPt{sub 2}. - Abstract: The phase formation sequence and the composition of phases induced by thermal annealing in a platinum (Pt) coated molybdenum (Mo) system were investigated by X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS) and transmission electron microscopy (TEM). The X-ray diffraction study of a 0.2 μm thick platinum layer deposited on a Mo substrate and annealed at temperatures between 800 °C and 900 °C for different periods of time shows the formation of MoPt{sub 2} and MoPt phases. It was also found that these phases nucleate sequentially and the MoPt{sub 2} phase becomes unstable at 900 °C after a longer annealing time of 8 h. Rutherford backscattering spectroscopy and transmission electron microscopy showed that the coating thickness approximately doubled after thermal annealing, from 0.22 μm to 0.46 μm, due to the formation of the Pt–Mo phases.

  17. Health implications of PAH release from coated cast iron drinking water distribution systems in The Netherlands.

    Science.gov (United States)

    Blokker, E J Mirjam; van de Ven, Bianca M; de Jongh, Cindy M; Slaats, P G G Nellie

    2013-05-01

    Coal tar and bitumen have been historically used to coat the insides of cast iron drinking water mains. Polycyclic aromatic hydrocarbons (PAHs) may leach from these coatings into the drinking water and form a potential health risk for humans. We estimated the potential human cancer risk from PAHs in coated cast iron water mains. In a Dutch nationwide study, we collected drinking water samples at 120 locations over a period of 17 days under various operational conditions, such as undisturbed operation, during flushing of pipes, and after a mains repair, and analyzed these samples for PAHs. We then estimated the health risk associated with an exposure scenario over a lifetime. During flushing, PAH levels frequently exceeded drinking water quality standards; after flushing, these levels dropped rapidly. After the repair of cast iron water mains, PAH levels exceeded the drinking water standards for up to 40 days in some locations. The estimated margin of exposure for PAH exposure through drinking water was > 10,000 for all 120 measurement locations, which suggests that PAH exposure through drinking water is of low concern for consumer health. However, factors that differ among water systems, such as the use of chlorination for disinfection, may influence PAH levels in other locations.

  18. Studies of chitosan/organic acid/Eudragit RS/RL-coated system for colonic delivery.

    Science.gov (United States)

    Kaur, Karanjit; Kim, Kwonho

    2009-01-21

    Prednisolone (PDS) beads were coated sequentially with (i) innermost hydrophobic layer of Eudragit RS/RL, (ii) middle drug release-triggering layer of chitosan, organic acid and Eudragit RS/RL, and (iii) outermost enteric coating layer. Continuous dissolution studies were carried out in artificial gastric fluid (pH 1.2), followed by intestinal fluid (pH 6.8), and finally in colonic fluid (pH 4 and 6) with and without beta-glucosidase. While drug release was prevented in the gastric and small-intestinal fluids, a continuous release was observed in the colonic fluid. Succinic acid provided the fastest rate of release in the colonic fluid compared to citric, tartaric or malic acid. A combined mechanism of drug release is proposed, which considers the swelling of chitosan and Eudragit RS/RL in the presence of succinic acid possibly via electrostatic interaction between the amine groups of chitosan/quaternary ammonium groups of Eudragit RS/RL and the carboxyl groups of succinic acid in aqueous medium. The results of plasma pharmacokinetic studies in Sprague-Dawley rats showed that the developed system provided a significant delay (T(max) 9.3 h) in the absorption profile of PDS compared with simple enteric-coated (T(max) 4 h) or powder (T(max) 1 h) formulation that was taken as proof for the colon-targeted delivery.

  19. AN EFFICIENT ALGORITHM FOR THE CONVEX HULL OF PLANAR SCATTERED POINT SET

    Directory of Open Access Journals (Sweden)

    Z. Fu

    2012-07-01

    Full Text Available Computing the convex hull of a point set is requirement in the GIS applications. This paper studies on the problem of minimum convex hull and presents an improved algorithm for the minimum convex hull of planar scattered point set. It adopts approach that dividing the point set into several sub regions to get an initial convex hull boundary firstly. Then the points on the boundary, which cannot be vertices of the minimum convex hull, are removed one by one. Finally the concave points on the boundary, which cannot be vertices of the minimum convex hull, are withdrew. Experimental analysis shows the efficiency of the algorithm compared with other methods.

  20. Blanch Resistant and Thermal Barrier NiAl Coating Systems for Advanced Copper Alloys

    Science.gov (United States)

    Raj, Sai V. (Inventor)

    2005-01-01

    A method of forming an environmental resistant thermal barrier coating on a copper alloy is disclosed. The steps include cleansing a surface of a copper alloy, depositing a bond coat on the cleansed surface of the copper alloy, depositing a NiAl top coat on the bond coat and consolidating the bond coat and the NiAl top coat to form the thermal barrier coating. The bond coat may be a nickel layer or a layer composed of at least one of copper and chromium-copper alloy and either the bond coat or the NiAl top coat or both may be deposited using a low pressure or vacuum plasma spray.

  1. Coated particle fuel for radioisotope power systems and heater units: status and future research needs

    Science.gov (United States)

    El-Genk, Mohamed S.; Tournier, Jean-Michel; Sholtis, Joseph A.; Lipinski, Ronald J.

    2000-01-01

    Coated particle fuel has been proposed recently for use in Radioisotope Power Systems (RPSs) and Radioisotope Heater Units (RHUs) for a variety of space missions requiring power levels from mWs to 10's or even hundreds of Watts. It can be made into different shapes and sizes of solid compacts, heating tapes, or paints. Using a conservative design approach, this fuel form could increase by 2.3-2.4 times the thermal power output of a LWRHU, while offering promise of enhanced safety. These performance figures are based on using single-size (500 μm) compacts of ZrC coated 238PuO2 kernels and assuming 10% and 5% He release, respectively, at 1723 K, following 10 years of storage. Using binary-size (300 and 1200 μm) fuel kernels in the compact increases the thermal power output by an additional 15%. 238PuO2 fuel kernels are intentionally sized (>=300 μm in diameter) to prevent any adverse radiological effects. They are non-respirable and non-inhalable and, if ingested, would simply be excreted with no radiological effects. The 238PuO2 fuel kernels are contained within a strong ZrC coating, which is designed to fully retain the fuel and the helium gas. Helium retention in large grain (>=300 μm) granular and polycrystalline fuel kernels is possible even at high temperatures (>1700 K). The former could be fabricated using binderless agglomeration or similar processes, while the latter could be fabricated using Sol-Gel or thermal plasma processes, with potentially less radioactive waste and fabrication contamination. In addition to summarizing the results of a recent effort investigating the performance of coated fuel particle compact (CPFC) and helium gas release, this paper identifies and discusses future research and testing needs. .

  2. Bioinspired Hand-Operated Smart-Wetting Systems Using Smooth Liquid Coatings.

    Science.gov (United States)

    Tenjimbayashi, Mizuki; Matsubayashi, Takeshi; Moriya, Takeo; Shiratori, Seimei

    2017-07-06

    Manually controllable "hand-operated" smart systems have been developed in many fields, including smart wetting materials, electronic devices, molecular machines, and drug delivery systems. Because complex morphological or chemical control are generally required, versatile strategies for constructing the system are technologically important. Inspired by the natural phenomenon of raindrops rarely bouncing and usually spreading on a puddle, we introduce a droplet-impact-triggering smart-wetting system using "non-smart" smooth liquid coating materials. Changing the droplet impact energy by changing the volume or casting height causes the droplet to completely bounce or spread on the liquid surface, regardless of the miscibility between the two liquids, owing to the stability of air layer. As the bouncing of a droplet on a liquid interface is not usually observed during wetting, we first analyze how the droplet bounces, then prove that the wettability is triggered by the droplet's impact energy, and finally introduce some applications using this system.

  3. Residual stress evaluation of coating films using welding residual stress and deformation analysis system. Yosetsu zanryu oryoku/henkei kaiseki system ni yoru coating himaku no zanryu oryoku hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Y.; Tanaka, K.; Takahashi, M.; Okada, T.; Saito, M. (Toshiba Corp., Tokyo (Japan)); Toyoda, M. (Osaka Univ., Osaka (Japan). Faculty of Engineering)

    1992-09-25

    With the objective that anybody having the basic knowledge on a simple welding technique can do easily welding residual stress and deformation analysis in an interactive mode, the welding residual stress and deformation analysis system (WRED) using a lap-top personal computer is being developed. In this report, an analytical study as well as an experimental study have been made on applicability of this system from the viewpoint of evaluating the residual stress chararcteristics of coating members in the WRED. In particular, the residual stress characteristics of ceramic coating films and those of graded coating members are described in detail. Part of the obtained results is as follows; as a result of the analysis by the WRED system of ceramic coating members processed each by the CVD method, the PVD method and the plasma flame coating method, only the CVD method and the plasma flame coating method have agreed well with the result of the residual stress measurement by the X-ray method. 12 refs., 8 figs., 2 tabs.

  4. New types of coating systems for steel sheets by high-rate evaporation in combination with plasma processes

    Energy Technology Data Exchange (ETDEWEB)

    Scheffel, B.; Metzner, C. [Fraunhofer-Institut fuer Elektronenstrahl und Plasmatechnik (FEP), Dresden (Germany); Ehlers, K.D. [Salzgitter AG Stahl und Technologie (Germany); Schuhmacher, B. [Dortmunder Oberflaechencentrum GmbH, Dortmund (Germany); Flossdorf, F.J.; Steinbeck, G. [Verein Deutscher Eisenhuettenleute (VDEh), Duesseldorf (Germany); Steffen, R. [Stahlwerke Bremen GmbH (Germany); Hagler, J. [voestalpine Stahl GmbH, Linz (Austria)

    2002-03-01

    High-rate evaporation in combination with plasma processes is a promising approach to obtain new types of steel sheet coating with improved corrosion resistance and application properties. To estimate the potential for the application of PVD-coatings (physical vapour deposition) different coating systems for steel sheet as well as for hot-dip or electro-galvanized steel sheet were designed. The samples were produced on a laboratory scale using PVD processes with very high deposition rates (in the order of 1 {mu}m s{sup -1}) as well as high-power plasma processes for the pre-treatment. The relationship between the composition, microstructure and properties of the coating systems, in particular concerning corrosion protection, abrasion during forming, phosphating and paint adhesion, were studied. It was found that the corrosion resistance of galvanized steel sheets can be considerably improved by vapour deposition of metal or inorganic films with a thickness of several hundred nanometers. Investigations on vapour deposition of titanium and stainless steel coatings on steel sheets, for applications in a severely corrosive environment, showed that the corrosion resistance in relation to the coating thickness can be significantly enhanced by means of plasma activation during the vapour deposition process. Finally, an outlook on possible industrial applications including an estimation of the process costs will be presented. For certain coating systems the results look promising. Consequently, these particular coating systems will be investigated in more detail by means of using a large-scale in-line deposition plant for metallic strips and sheets. (orig.)

  5. New backing layer for transdermal drug delivery systems: coatings based on fatty acid and beeswax on chitosan films

    OpenAIRE

    Rullier-Birat, Bénédicte; Cazalbou, Sophie; Nassar, Maria Alejandra; Sandrine, Cavalie; Tourrette, Audrey

    2015-01-01

    International audience; Fatty acids and beeswax are known to improve barrier properties of biodegradable materials. Thanks to their hydrophobic character, they can act as a barrier against water giving to the material more occlusive properties. This work was aimed at preparing fatty acid and beeswax coatings for a transdermal drug delivery system. In order to study occlusive properties of these coatings, water vapor permeability and contact angle measurements were carried out. The most homoge...

  6. Bioactivities and antiradical properties of millet grains and hulls.

    Science.gov (United States)

    Chandrasekara, Anoma; Shahidi, Fereidoon

    2011-09-14

    Antioxidant activities of phenolic extracts of kodo and pearl millet whole grains, dehulled grains, and hulls were examined by monitoring inhibition of radical-induced DNA scission, human low-density lipoprotein (LDL) cholesterol, and phospholipid liposome oxidation. Total phenolic content (TPC), hydroxyl and peroxyl radical inhibition, and antiproliferative activities against HT-29 cells were also determined. Major hydroxycinnamic acids in dehulled grains and hulls were identified and quantified using HPLC. Phenolic extract of kodo millet exhibited higher inhibition activities against oxidation of LDL cholesterol and liposome than that of pearl millet. All phenolic extracts exhibited a dose-dependent inhibition of DNA scission. The TPC of hulls of kodo and pearl millets were 3 times higher than those of their corresponding whole grains. At the end of 96 h of incubation, kodo millet extracts inhibited cell proliferation in the range of 75-100%. Antioxidant activities of phenolic extracts were in the order hull > whole grain > dehulled grain. Dehulling reduced the antioxidant potential of whole millet grains. Ferulic and p-coumaric acids were the major hydroxycinnamic acids, and their contents ranged from 17.8 to 1685 μg/g defatted meal and from 3.5 to 680 μg/g defatted meal, respectively. Dehulled grains, as well as the hull fraction, may serve as potential sources of nutraceutical and functional food ingredients in health promotion.

  7. Ship Resistance of Quadramaran With Various Hull Position Configurations

    Institute of Scientific and Technical Information of China (English)

    Yanuar; Gunawan; A Muhyi; A Jamaluddin

    2016-01-01

    Multihull ships are widely used for sea transportation, and those with four hulls are known as quadramarans. Hull position configurations of a quadramaran include the diamond, tetra, and slice. In general, multihull vessels traveling at high speeds have better hydrodynamic efficiency than monohull ships. This study aims to identify possible effects of various quadramaran hull position configurations on ship resistance for hull dimensions of 2 m length, 0.21 m breadth, and 0.045 m thickness. We conducted a towing test in which we varied the hull spacing and speed atFr values between 0.08 and 0.62 and measured the total resistance using a load cell transducer. The experimental results reveal that the lowest total resistance was achieved with a diamond quadramaran configuration atFr = 0.1-0.6 and an effective interference factor of up to 0.35 withS/L = 3/10 andR/L = 1/2 atFr = 0.62.

  8. Region-of-interest volumetric visual hull refinement

    KAUST Repository

    Knoblauch, Daniel

    2010-01-01

    This paper introduces a region-of-interest visual hull refinement technique, based on flexible voxel grids for volumetric visual hull reconstructions. Region-of-interest refinement is based on a multipass process, beginning with a focussed visual hull reconstruction, resulting in a first 3D approximation of the target, followed by a region-of-interest estimation, tasked with identifying features of interest, which in turn are used to locally refine the voxel grid and extract a higher-resolution surface representation for those regions. This approach is illustrated for the reconstruction of avatars for use in tele-immersion environments, where head and hand regions are of higher interest. To allow reproducability and direct comparison a publicly available data set for human visual hull reconstruction is used. This paper shows that region-of-interest reconstruction of the target is faster and visually comparable to higher resolution focused visual hull reconstructions. This approach reduces the amount of data generated through the reconstruction, allowing faster post processing, as rendering or networking of the surface voxels. Reconstruction speeds support smooth interactions between the avatar and the virtual environment, while the improved resolution of its facial region and hands creates a higher-degree of immersion and potentially impacts the perception of body language, facial expressions and eye-to-eye contact. Copyright © 2010 by the Association for Computing Machinery, Inc.

  9. Functional improvement of antibody fragments using a novel phage coat protein III fusion system

    DEFF Research Database (Denmark)

    Jensen, Kim Bak; Larsen, Martin; Pedersen, Jesper Søndergaard;

    2002-01-01

    Functional expressions of proteins often depend on the presence of host specific factors. Frequently recombinant expression strategies of proteins in foreign hosts, such as bacteria, have been associated with poor yields or significant loss of functionality. Improvements in the performance...... of heterologous expression systems will benefit present-day quests in structural and functional genomics where high amounts of active protein are required. One example, which has been the subject of considerable interest, is recombinant antibodies or fragments thereof as expressions of these in bacteria......(s) of the filamentous phage coat protein III. Furthermore, it will be shown that the observed effect is neither due to improved stability nor increased avidity....

  10. Durability and CMAS Resistance of Advanced Environmental Barrier Coatings Systems for SiC/SiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming

    2015-01-01

    Environmental barrier coatings (EBCs) and SiCSiC ceramic matrix composites (CMCs) systems will play a crucial role in next generation turbine engines for hot-section component applications because of their ability to significantly increase engine operating temperatures with improved efficiency, reduce engine weight and cooling requirements. This paper will emphasize advanced environmental barrier coating developments for SiCSiC turbine airfoil components, by using advanced coating compositions and processing, in conjunction with mechanical and environment testing and durability validations. The coating-CMC degradations and durability in the laboratory simulated engine fatigue-creep and complex operating environments are being addressed. The effects of Calcium-Magnesium-Alumino-Silicate (CMAS) from road sand or volcano-ash deposits on the degradation mechanisms of the environmental barrier coating systems will be discussed. The results help understand the advanced EBC-CMC system performance, aiming at the durability improvements of more robust, prime-reliant environmental barrier coatings for successful applications of the component technologies and lifing methodologies.

  11. Design Optimization of Liquid Fueled High Velocity Oxy- Fuel Thermal Spraying Technique for Durable Coating for Fossil Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Choudhuri, Ahsan [Univ. of Texas, El Paso, TX (United States); Love, Norman [Univ. of Texas, El Paso, TX (United States)

    2016-11-04

    High-velocity oxy–fuel (HVOF) thermal spraying was developed in 1930 and has been commercially available for twenty-five years. HVOF thermal spraying has several benefits over the more conventional plasma spray technique including a faster deposition rate which leads to quicker turn-around, with more durable coatings and higher bond strength, hardness and wear resistance due to a homogeneous distribution of the sprayed particles. HVOF thermal spraying is frequently used in engineering to deposit cermets, metallic alloys, composites and polymers, to enhance product life and performance. HVOF thermal spraying system is a highly promising technique for applying durable coatings on structural materials for corrosive and high temperature environments in advanced ultra-supercritical coal- fired (AUSC) boilers, steam turbines and gas turbines. HVOF thermal spraying is the preferred method for producing coatings with low porosity and high adhesion. HVOF thermal spray process has been shown to be one of the most efficient techniques to deposit high performance coatings at moderate cost. Variables affecting the deposit formation and coating properties include hardware characteristics such as nozzle geometry and spraying distance and process parameters such as equivalence ratio, gas flow density, and powder feedstock. In the spray process, the powder particles experience very high speeds combined with fast heating to the powder material melting point or above. This high temperature causes evaporation of the powder, dissolution, and phase transformations. Due to the complex nature of the HVOF technique, the control and optimization of the process is difficult. In general, good coating quality with suitable properties and required performance for specific applications is the goal in producing thermal spray coatings. In order to reach this goal, a deeper understanding of the spray process as a whole is needed. Although many researchers studied commercial HVOF thermal spray

  12. Solar selective black nickel-cobalt coatings on aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Shashikala, A.R.; Sharma, A.K.; Bhandari, D.R. [Thermal System Group, ISRO Satellite Centre, Bangalore 560 017 (India)

    2007-04-16

    Solar selective black nickel-cobalt plating on pre cleaned aluminum alloy substrates with nickel undercoat were investigated. Process optimization was carried out by the hull cell experiments investigating the influence of operating variables on the optical selectivity of the coating. The coatings were characterized with scanning electron microscope, X-ray diffraction, energy dispersive X-ray spectroscopic and polarization studies. Evaluation of the coatings was carried out by adhesion, measurement of coating thickness and optical properties, humidity, thermal cycling, thermo-vacuum performance and thermal stability tests. (author)

  13. Effects of Chromate and Non-Chromate Coating Systems on Environmentally Assisted Fatigue of an Aluminum Alloy

    Science.gov (United States)

    Schubbe, Joel J.; Westmoreland, Sophoria N.

    2014-10-01

    Fatigue crack growth testing of 2024-T3 Aluminum plate was performed using compact tension (CT) specimens with chromate and non-chromate primer paint systems to evaluate the effects of the coatings on fatigue crack growth rates. The tests were conducted in lab air and sea water environments for each of the coating systems. Standard E399 CT specimens were tested to determine the influence level of environmentally assisted cracking (corrosion fatigue) on crack growth rates and cyclic count to prescribed pre-crack and final crack lengths. Increasing stress range (Δ K) tests were conducted at 10 Hz in the range of 6.5 to 26.5 MPa. It was determined that the coated specimens exhibited a 12% shorter total life, on average, than the bare specimens for the lab air cases. In the case of salt water exposure, the coated specimens exhibited approximately 10% life increase over the bare specimens. The number of cycles to the 2.54 mm pre-crack length for the coated specimens was all less than the cycle count for the bare tests. In each case (coated or bare), there was an increased growth rate at the lower stress ranges in the salt water environment, with the chromate system case displaying the smallest change (increase). It can be concluded that the coated specimens initiate cracks and propagate faster than the bare specimens for short cracks at low stress range, but the environmental influence on the specimens is quickly overshadowed as the cracks elongate and the rate of growth increases. The coated specimens exhibited a higher total life cycle count to final crack length for this testing.

  14. Irradiated-Microsphere Gamma Analyzer (IMGA): an integrated system for HTGR coated particle fuel performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kania, M.J.; Valentine, K.H.

    1980-02-01

    The Irradiated-Microsphere Gamma Analyzer (IMGA) System, designed and built at ORNL, provides the capability of making statistically accurate failure fraction measurements on irradiated HTGR coated particle fuel. The IMGA records the gamma-ray energy spectra from fuel particles and performs quantitative analyses on these spectra; then, using chemical and physical properties of the gamma emitters it makes a failed-nonfailed decision concerning the ability of the coatings to retain fission products. Actual retention characteristics for the coatings are determined by measuring activity ratios for certain gamma emitters such as /sup 137/Cs//sup 95/Zr and /sup 144/Ce//sup 95/Zr for metallic fission product retention and /sup 134/Cs//sup 137/Cs for an indirect measure of gaseous fission product retention. Data from IMGA (which can be put in the form of n failures observed in N examinations) can be accurately described by the binomial probability distribution model. Using this model, a mathematical relationship between IMGA data (n,N), failure fraction, and confidence level was developed. To determine failure fractions of less than or equal to 1% at confidence levels near 95%, this model dictates that from several hundred to several thousand particles must be examined. The automated particle handler of the IMGA system provides this capability. As a demonstration of failure fraction determination, fuel rod C-3-1 from the OF-2 irradiation capsule was analyzed and failure fraction statistics were applied. Results showed that at the 1% failure fraction level, with a 95% confidence level, the fissile particle batch could not meet requirements; however, the fertile particle exceeded these requirements for the given irradiation temperature and burnup.

  15. Double-hulling of the bulk carriers%散货船的双壳化

    Institute of Scientific and Technical Information of China (English)

    莫中华

    2004-01-01

    This article analyses the technical background of the double-hulling of the bulk carriers and describes the 3 major problems for its design. It finally compares the characteristics of the single/double hull bulk carriers by listing.

  16. Experimental Evaluation of the Hydrodynamic Response of Crew Boat Hulls

    DEFF Research Database (Denmark)

    Pecher, Arthur; Kofoed, Jens Peter

    This report presents the results of an experimental study on 3 different hulls of crew boats intended for service to offshore wind turbines. Their hydrodynamic behaviour has been tested in various sea states representing general wave conditions that could be expected at offshore wind farms. Two...... main setups were used during the tests, corresponding to the hulls being connected to an offshore windmill and being free floating. The following aspects were the main subjects of investigation: • The Response Amplitude Operators of the hulls in two different configurations and with waves coming from 3...... the supervision of Jens Peter Kofoed in the deep wave basin in the Hydraulics and Coastal Engineering laboratory at Aalborg University during spring 2012....

  17. ISOLATION AND CHARACTERIZATION OF NANOFIBRILLATED CELLULOSE FROM OAT HULLS

    Directory of Open Access Journals (Sweden)

    Giovanni B. Paschoal

    2015-05-01

    Full Text Available The objectives of this work were to investigate the microstructure, crystallinity and thermal stability of nanofibrillated cellulose obtained from oat hulls using bleaching and acid hydrolysis at a mild temperature (45 ºC followed by ultrasonication. The oat hulls were bleached with peracetic acid, and after bleaching, the compact structure around the cellulosic fibers was removed, and the bundles became individualized. The extraction time (30 or 60 min did not affect the properties of the nanofibrillated cellulose, which presented a higher crystallinity index and thermal stability than the raw material (oat hulls. The nanocellulose formed interconnected webs of tiny fibers with diameters of 70-100 nm and lengths of several micrometers, producing nanofibers with a relatively high aspect ratio, thus indicating that these materials are suitable for polymer reinforcement.

  18. On the Global Ship Hull Bending Energy in Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Li, Y.

    2004-01-01

    During ship collisions part of the kinetic energy of the involved vessels prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can be stored in elastic...... absorbed by the struck ship normally is small and varies from 1 to 6 % of the energy released for crushing. The energy stored as elastic global hull girder vibrations depends on the ship mass, the local stiffness of the side structure, and of the position of contact. The results also show that for highly...... hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non trivial part of the energy released for structural deformation during the collision can be absorbed as elastic energy in global...

  19. On the global ship hull bending energy in ship collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Li, Yujie

    2009-01-01

    be stored in elastic hull vibrations during a ship collision. When a ship side is strengthened in order to improve the crashworthiness it has been argued in the scientific literature that a non-trivial part of the energy released for structural deformation during the collision can be absorbed as elastic...... energy absorbed by the struck ship normally is small and varies from 1 to 6% of the energy released for crushing. The energy stored as elastic global hull girder vibrations depends on the ship mass, the local stiffness of the side structure, and of the position of contact. The results also show......During ship collisions part of the kinetic energy of the involved vessels immediately prior to contact is absorbed as energy dissipated by crushing of the hull structures, by friction and by elastic energy. The purpose of this report is to present an estimate of the elastic energy that can...

  20. The interaction of extreme waves with hull elements

    Science.gov (United States)

    Galiev, Shamil; Flay, Richard

    2010-05-01

    The problem of the impact of a rogue wave onto a deformable marine structure is formulated in a few publications (see, for example, a short review in http://researchspace.auckland.ac.nz/handle/2292/4474). In this paper the results from numerical and experimental investigations of the effect of cavitation on the deformation of a hull element, loaded by a wall of water, generated by an extreme ocean surface wave are considered. The hull element is modelled as a circular metal plate with the edge of the plate rigidly clamped. The plate surface is much smaller than the surface of the wave front, so that at the initial moment of the interaction, the pressure is constant on the plate surface. At the next instant, because of the plate deformation, axisymmetric loading of the plate occurs. The influences of membrane forces and plastic deformations are ignored, and therefore, the equation of plate motion has the following classical form Eh3(wrrrr+2r -1wrrrr- r-2wrr+r-3wr) = - 121- ν2)[ρhwtt+ δ(r,t)(p+ ρ0a0wt)]. Here w is the plate displacement, subscripts t and rindicate derivatives with respect to time and the radial coordinate, PIC is the plate material density, his the plate thickness, Eis Young's modulus, PIC is Poisson's ratio and p is the pressure of the incident surface wave measured on the wall, PIC is the water density, PIC is the speed of sound in water, and PIC is the normal velocity of the plate. The term PIC takes into account the effect of the deformability of the plate. Obviously, the hull of a vessel is not rigid like a solid wall, but starts to deform and to move. This motion produces a reflected pressure wave, which travels from the hull into the water wave with a magnitude equal to PIC . The normal velocity is positive so the reflected pressure PIC is negative (tensile wave). If the fluid pressure drops below some critical value pk, the wet plate surface separates from the water, and cavitation may be generated. The function δ(r,t) takes into account

  1. Inside-pipe hydrophobic coating method promoting dropwise condensation in a passive cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Joo Won; Kang, Jun Young; Hwang, Kyoung Won; Park, Hyun Sun; Kiyofumi, Moriyama [POSTECH, Pohang(Korea, Republic of); Kim, Moo Hwan [Korea Institute of nuclear safety, Daejeon(Korea, Republic of)

    2015-05-15

    Submerged by large tsunami, active cooling system was not operated to cool down decay heat. Likewise, station black out can lead to severe accident so that the necessity of cooling system without requesting any electric power was stressed out. Passive Auxiliary Feedwater System(PAFS) is one of the passive cooling systems suggested by Korea Atomic Energy Research Institute(KAERI). It has hundreds of slightly inclined horizontal U-shaped pipes submerged in a large water pool. Under the accident circumstances, this system cools steam that comes from the steam generator into condensed water inside the pipes without any electric power. These pipes are made of stainless steel 304L, with the diameter of 50 mm, and the length of 8 m. The main heat transfer phenomenon inside a pipe is the condensation phenomenon. There are two modes of condensation: one is filmwise condensation(FWC) and the other is dropwise condensation(DWC). On a surface wetted by a liquid well, FWC occurs to form liquid film. The final goal of this study is to increase cooling capacity of passive safety system like PAFS. Up to now, the attempts to increase condensation heat transfer were limited to make finned tube. DWC which has higher heat transfer coefficient was only promoted on vertical plates or external pipes. By promoting DWC inside a pipe, condensation heat transfer will be fundamentally enhanced. In this paper, hydrophobic coating inside a pipe method will be presented for promoting DWC, and its condensation heat transfer performance will be evaluated by conducting condensation experiment on a vertical plate. The inside-pipe hydrophobic coating method was developed using Teflon, and it was checked that DWC was promoted by this method with visualization results. At the saturation pressure of 145kPa, average heat transfer coefficient for DWC was 53.3 kW/m''2/K, and that for FWC was 13.5 kW/m''2/K. Based on this results, it can be concluded that this coating method will

  2. Creep behavior of plasma sprayed NiCr and NiCrAl coating-based systems

    Institute of Scientific and Technical Information of China (English)

    Xiancheng ZHANG; Changjun LIU; Fuzhen XUAN; Zhengdong WANG; Shan-Tung TU

    2011-01-01

    The creep behavior of the plasma sprayed NiCr and NiCrAl coating/Nickel alloy 690substrate systems at 1033 K was investigated. Results showed that there was almost no difference in the creep lives between the NiCr and NiCrAl coated specimens at a given stress level, since the contents of Cr used in the NiCr and NiCrAl powders are almost same. The relationship between the minimum creep rate and the applied stress followed the well-known Norton's power law, εmin=Aσn, with the values of A=2.66× 10-16 Mpa-n.h-1 and n=6.48. The relation between the applied stress and time to rupture of the coated specimens can be estimated by using Larson-Miller equation. The θ projection method can be used to accurately characterize the creep behavior of the coated specimens.

  3. Effect of Residual Stresses and Prediction of Possible Failure Mechanisms on Thermal Barrier Coating System by Finite Element Method

    Science.gov (United States)

    Ranjbar-Far, M.; Absi, J.; Mariaux, G.; Shahidi, S.

    2010-09-01

    This work is focused on the effect of the residual stresses resulting from the coating process and thermal cycling on the failure mechanisms within the thermal barrier coating (TBC) system. To reach this objective, we studied the effect of the substrate preheating and cooling rate on the coating process conditions. A new thermomechanical finite element model (FEM) considering a nonhomogeneous temperature distribution has been developed. In the results, we observed a critical stress corresponding to a low substrate temperature and high cooling rate during spraying of the top-coat material. Moreover, the analysis of the stress distribution after service shows that more critical stresses are obtained in the case where residual stresses are taken into account.

  4. Tribological characterization of selected hard coatings

    OpenAIRE

    Karlsson, Patrik

    2009-01-01

    Hard coatings are often used for protection of tool surfaces due to coating properties like low friction and high wear resistance. Even though many of the hard coatings have been tested for wear, it is important to try new wear test setups to fully understand tribological mechanisms and the potential of hard coatings. Few experiments have been performed with dual-coated systems where the sliding contact surfaces are coated with the same, or different, hard coating. The dual-coated system coul...

  5. Hull-form optimization of KSUEZMAX to enhance resistance performance

    Directory of Open Access Journals (Sweden)

    Park Jong-Heon

    2015-01-01

    Full Text Available This paper deploys optimization techniques to obtain the optimum hull form of KSUEZMAX at the conditions of full-load draft and design speed. The processes have been carried out using a RaPID-HOP program. The bow and the stern hull-forms are optimized separately without altering neither, and the resulting versions of the two are then combined. Objective functions are the minimum values of wave-making and viscous pressure resistance coefficients for the bow and stern. Parametric modification functions for the bow hull-form variation are SAC shape, section shape (U-V type, DLWL type, bulb shape (bulb height and size; and those for the stern are SAC and section shape (U-V type, DLWL type. WAVIS version 1.3 code is used for the potential and the viscous-flow solver. Prior to the optimization, a parametric study has been conducted to observe the effects of design parameters on the objective functions. SQP has been applied for the optimization algorithm. The model tests have been conducted at a towing tank to evaluate the resistance performance of the optimized hull-form. It has been noted that the optimized hull-form brings 2.4% and 6.8% reduction in total and residual resistance coefficients compared to those of the original hull-form. The propulsive efficiency increases by 2.0% and the delivered power is reduced 3.7%, whereas the propeller rotating speed increases slightly by 0.41 rpm.

  6. DETERMINATION OF CREEP PROPERTIES OF THERMAL BARRIER COATING(TBC) SYSTEMS FROM THE INDENTATION CREEP TESTING WITH ROUND FLAT INDENTERS

    Institute of Scientific and Technical Information of China (English)

    B. Zhao; B.X. Xu; J. Liu; Z.F. Yue

    2004-01-01

    Indentation creep behavior with cylindrical flat indenters on the thermal barrier coating (TBC) was studied by finite element method (FEM). On the constant applied indentation creep stress, there is a steady creep rate for each case studied for different creep properties of the TBC system. The steady creep depth rate depends on the applied indentation creep stress and size of the indenters as well as the creep properties of the bond coat of the TBC and the substrate. The possibilities to determine the creep properties of a thermal barrier system from indention creep testing were discussed. As an example, with two different size indenters, the creep properties of bond coat of the TBC system can be derived by an inverse FEM method. This study not only provides a numerical method to obtain the creep properties of the TBC system, but also extends the application of indentation creep method with cylindrical flat indenters.

  7. Coated magnetic particles in electrochemical systems: Synthesis, modified electrodes, alkaline batteries, and paste electrodes

    Science.gov (United States)

    Unlu, Murat

    Magnetic field effects on electrochemical reactions have been studied and shown to influence kinetics and dynamics. Recently, our group has introduced a novel method to establish magnetic field effects by incorporating inert, magnetic microparticles onto the electrode structure. This modification improved several electrochemical systems including modified electrodes, alkaline batteries, and fuel cells. This dissertation describes the applicability of magnetic microparticles and the understanding of magnetic field effects in modified electrodes, alkaline batteries, and paste electrodes. Magnetic effects are studied on electrodes that are coated with an ion exchange polymer that embeds chemically inert, commercial, magnetic microparticles. The flux (electrolysis current) of redox probe to the magnetically modified system is compared to a similar non-magnetic electrode. Flux enhancements of 60% are achieved at magnetically modified electrode as compared to non-magnetic controls. In addition to modifying electrode surfaces, the incorporation of magnetic microparticles into the electrode material itself establishes a 20% increase in flux. Possible magnetic field effects are evaluated. Study of samarium cobalt modified electrolytic manganese dioxide, EMD electrodes further establish a magnetic effect on alkaline cathode performance. Magnetic modification improves alkaline battery performance in primary and secondary applications. The reaction mechanism is examined through voltammetric methods. This work also includes coating protocols to produce inert magnetic microparticles with high magnetic content. Magnetite powders are encapsulated in a polymer matrix by dispersion polymerization. Composite particles are examined in proton exchange membrane fuel cells to study carbon monoxide tolerance.

  8. Investigation of an Intumescent Coating System in Pilot and Laboratory-scale Furnaces

    DEFF Research Database (Denmark)

    Nørgaard, Kristian Petersen

    (450 - 600 °C), at which the collapse may occur, is the use of a fire protective intumescent coating, which swells when exposed to temperatures above about 200 °C. The swelling of the intumescent coating happens according to a complex sequence of chemical reactions, whereby the coating forms a porous...... char, which thermally insulates the substrate. In addition to the coating itself, several process parameters influence the performance of the intumescent coating. Such parameters may for instance be the interaction with an underlying anticorrosive primer, the heating rate employed, or the oxygen...... content in the fire. In this work, focus has been on process parameters for an intumescent coating for so-called cellulosic fires. The thesis contains five chapters, where Chapter 1 is a literature survey providing background knowledge on coatings, intumescent coatings in particular, and fire scenarios...

  9. The Projective Hull of Certain Curves in C^2

    OpenAIRE

    Harvey, F. Reese; Lawson, Jr, H. Blaine; Wermer, John

    2006-01-01

    The projective hull X^ of a subset X in complex projective space P^n is an analogue of the classical polynomial hull of a set in C^n. If X is contained in an affine chart C^n on P^n, then the affine part of X^ is the set of points x in C^n for which there exists a constant M=M_x so that |p(x)| 0. Let X^(M) be the set of points x where M_x can be chosen < M. Using an argument of E. Bishop, we show t...

  10. Analysis of international one meter class hull shapes

    OpenAIRE

    Pons Forn, Ariadna

    2015-01-01

    It has been observed that up to 23 different model were racing the IOM worlds in 2014. These means that skippers has a broad range of designs when buying a new boat. This project aims to analyse different hull shapes of International One Metre Class in order to have the necessary technical information to know how the hull shapes affect the seakeeping and boat performance. Every year the number of skippers and design keep increasing (2825 last year), therefore understanding how an IOM boat per...

  11. Finding Convex Hulls Using Quickhull on the GPU

    CERN Document Server

    Tzeng, Stanley

    2012-01-01

    We present a convex hull algorithm that is accelerated on commodity graphics hardware. We analyze and identify the hurdles of writing a recursive divide and conquer algorithm on the GPU and divise a framework for representing this class of problems. Our framework transforms the recursive splitting step into a permutation step that is well-suited for graphics hardware. Our convex hull algorithm of choice is Quickhull. Our parallel Quickhull implementation (for both 2D and 3D cases) achieves an order of magnitude speedup over standard computational geometry libraries.

  12. Design of convex hull plate forming by pure line heating

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-biao; JI Zhuo-shang; LIU Yu-jun

    2004-01-01

    This paper presents a ship-hull plate forming way by pure line heating. The heating lines forming the required bending angle is determined by curvature analysis method. Heating along the calculated heating lines results in bland plate with initial transverse curvature. Then, the plate with desired convex shape can be obtained by heating in the longitudinal edge. This is the whole forming process by pure line heating. This paper presents a method of plane development for ship-hull plate with B-spline surface representation, and provides the shrinkage heating lines in the forming process. This forming way would facilitate temperature control and make plate forming automatically easy.

  13. Structurally Integrated, Damage Tolerant Thermal Spray Coatings: Processing Effects on Surface and System Functionalities

    Science.gov (United States)

    Vackel, Andrew

    Thermal Spray (TS) coatings have seen extensive application as protective surfaces to enhance the service life of substrates prone to damage in their operating environment (wear, corrosion, heat etc.). With the advent of high velocity TS processes, the ability to deposit highly dense (>99%) metallic and cermet coatings has further enhanced the protective ability of these coatings. In addition to surface functionality, the influence of the coating application on the mechanical performance of a coated component is of great concern when such a component will experience either static or cyclic loading during service. Using a process mapping methodology, the processing-property interplay between coating materials meant to provide damage tolerant surface or for structural restoration are explored in terms of relevant mechanical properties. Most importantly, the residual stresses inherent in TS deposited coatings are shown to play a significant role in the integrated mechanical performance of these coatings. Unique to high velocity TS processes is the ability to produce compressive stresses within the deposit from the cold working induced by the high kinetic energy particles upon impact. The extent of these formation stresses are explored with different coating materials, as well as processing influence. The ability of dense TS coatings to carry significant structural load and synergistically strengthen coated tensile specimens is demonstrated as a function of coating material, processing, and thickness. The sharing of load between the substrate and otherwise brittle coating enables higher loads before yield for the bi-material specimens, offering a methodology to improve the tensile performance of coated components for structural repair or multi-functionality (surface and structure). The concern of cyclic fatigue damage in coated components is explored, since the majority of service application are designed for loading to be well below the yield point. The role of

  14. 46 CFR 32.63-20 - Hull structure-B/ALL.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Hull structure-B/ALL. 32.63-20 Section 32.63-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS SPECIAL EQUIPMENT, MACHINERY, AND HULL..., and Carrying Certain Dangerous Bulk Cargoes § 32.63-20 Hull structure—B/ALL. (a) General. In addition...

  15. Of Curriculum Conceptions, Orientations, and Cultures: A Rejoinder to John E. Hull

    Science.gov (United States)

    Van Brummelen, Harro

    2009-01-01

    In this article, the author presents a rejoinder to John E. Hull. Van Brummelen first states his appreciation of John Hull's thoughtful evaluation of his views of curriculum, views in which many Christian educators have played a part. It has been several decades since the author spelled out what Hull calls an "education for discipleship"…

  16. 14 CFR 29.519 - Hull type rotorcraft: Water-based and amphibian.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull type rotorcraft: Water-based and amphibian. 29.519 Section 29.519 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... § 29.519 Hull type rotorcraft: Water-based and amphibian. (a) General. For hull type rotorcraft,...

  17. 46 CFR 71.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery..., boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels, the standards... and inspection of hulls, boilers, and machinery, and the certificate of classification...

  18. Boat's hull modeling with low-cost triangulation scanners

    Science.gov (United States)

    Guidi, Gabriele; Micoli, Laura L.; Russo, Michele

    2005-01-01

    In a 3D acquisition project range maps collected around the object to be modeled, need to be integrated. With portable range cameras these range maps are taken from unknown positions and their coordinate systems are local to the sensor. The problem of unifying all the measurements in a single reference system is solved by taking contiguous range maps with a suitable overlap level; taking one map as reference and doing a rototranslation of the adjacent ones by using an "Iterative Closest Point" (ICP) method. Depending on the 3D features over the acquired surface and on the amount of overlapping, the ICP algorithm convergence can be more or less satisfactory. Anyway it always has a random component depending on measurement uncertainty. Therefore, although each individual scan has a very good accuracy, the error's propagation may produce deviations in the aligned set respect to real surface points. In this paper a systematic study of the different alignment modality and the consequent total metric distortions on the final model, is shown. In order to experiment these techniques a case-study of industrial interest was chosen: the 3D modeling of a boat's hull mold. The experiments involved a triangulation based laser scanner integrated with a digital photogrammetry system. In order to check different alignment procedures, a Laser Radar capable to scan all the object surface with a single highly accurate scan, was used to create a "gold-standard" data set. All the experiments were compared with this reference and from the comparison several interesting methodological conclusions have been obtained.

  19. Evolving lessons on nanomaterial-coated viral vectors for local and systemic gene therapy.

    Science.gov (United States)

    Kasala, Dayananda; Yoon, A-Rum; Hong, Jinwoo; Kim, Sung Wan; Yun, Chae-Ok

    2016-07-01

    Viral vectors are promising gene carriers for cancer therapy. However, virus-mediated gene therapies have demonstrated insufficient therapeutic efficacy in clinical trials due to rapid dissemination to nontarget tissues and to the immunogenicity of viral vectors, resulting in poor retention at the disease locus and induction of adverse inflammatory responses in patients. Further, the limited tropism of viral vectors prevents efficient gene delivery to target tissues. In this regard, modification of the viral surface with nanomaterials is a promising strategy to augment vector accumulation at the target tissue, circumvent the host immune response, and avoid nonspecific interactions with the reticuloendothelial system or serum complement. In the present review, we discuss various chemical modification strategies to enhance the therapeutic efficacy of viral vectors delivered either locally or systemically. We conclude by highlighting the salient features of various nanomaterial-coated viral vectors and their prospects and directions for future research.

  20. Coated Particles Fuel Compact-General Purpose Heat Source for Advanced Radioisotope Power Systems

    Science.gov (United States)

    El-Genk, Mohamed S.; Tournier, Jean-Michel

    2003-01-01

    Coated Particles Fuel Compacts (CPFC) have recently been shown to offer performance advantage for use in Radioisotope Heater Units (RHUs) and design flexibility for integrating at high thermal efficiency with Stirling Engine converters, currently being considered for 100 We. Advanced Radioisotope Power Systems (ARPS). The particles in the compact consist of 238PuO2 fuel kernels with 5-μm thick PyC inner coating and a strong ZrC outer coating, whose thickness depends on the maximum fuel temperature during reentry, the fuel kernel diameter, and the fraction of helium gas released from the kernels and fully contained by the ZrC coating. In addition to containing the helium generated by radioactive decay of 238Pu for up to 10 years before launch and 10-15 years mission lifetime, the kernels are intentionally sized (>= 300 μm in diameter) to prevent any adverse radiological effects on reentry. This paper investigates the advantage of replacing the four iridium-clad 238PuO2 fuel pellets, the two floating graphite membranes, and the two graphite impact shells in current State-Of-The-Art (SOA) General Purpose Heat Source (GPHS) with CPFC. The total mass, thermal power, and specific power of the CPFC-GPHS are calculated as functions of the helium release fraction from the fuel kernels and maximum fuel temperature during reentry from 1500 K to 2400 K. For the same total mass and volume as SOA GPHS, the generated thermal power by single-size particles CPFC-GPHS is 260 W at Beginning-Of-Mission (BOM), versus 231 W for the GPHS. For an additional 10% increase in total mass, the CPFC-GPHS could generate 340 W BOM; 48% higher than SOA GPHS. The corresponding specific thermal power is 214 W/kg, versus 160 W/kg for SOA GPHS; a 34% increase. Therefore, for the same thermal power, the CPFC-GPHS is lighter than SOA GPHS, while it uses the same amount of 238PuO2 fuel and same aeroshell. For the same helium release fraction and fuel temperature, binary-size particles CPFC-GPHS could

  1. Plasma Spraying and Characterization of Tungsten Carbide-Cobalt Coatings by the Water-Stabilized System WSP

    Directory of Open Access Journals (Sweden)

    Pavel Ctibor

    2009-01-01

    Full Text Available Tungsten carbide-cobalt powders (WC-17wt% Co were plasma sprayed by a water-stabilized system WSP. Experiments with variable feeding distances and spray distances were carried out. Thinner coatings were deposited on carbon steel substrates and thicker coatings on stainless steel substrates to compare different cooling conditions. Basic characterization of coatings was done by XRD, SEM, and light microscopy plus image analysis. Microhardness was measured on polished cross-sections. The main focus of investigation was resistance against wear in dry as well as wet conditions. The appropriate tests were performed with set-ups based on ASTM G65 and G75, respectively. The influence of spray parameters onto coating wear performance was observed. The results of mechanical tests were discussed in connection with changes of phase composition and with the quality of the coating's microstructure. The results show that for obtaining the best possible WC-17Co coating with WSP process, from the viewpoint of wear resistance, the desired parameters combination is long feeding distance combined with short spray distance.

  2. Application of ICH Q9 Quality Risk Management Tools for Advanced Development of Hot Melt Coated Multiparticulate Systems.

    Science.gov (United States)

    Stocker, Elena; Becker, Karin; Hate, Siddhi; Hohl, Roland; Schiemenz, Wolfgang; Sacher, Stephan; Zimmer, Andreas; Salar-Behzadi, Sharareh

    2017-01-01

    This study aimed to apply quality risk management based on the The International Conference on Harmonisation guideline Q9 for the early development stage of hot melt coated multiparticulate systems for oral administration. N-acetylcysteine crystals were coated with a formulation composing tripalmitin and polysorbate 65. The critical quality attributes (CQAs) were initially prioritized using failure mode and effects analysis. The CQAs of the coated material were defined as particle size, taste-masking efficiency, and immediate release profile. The hot melt coated process was characterized via a flowchart, based on the identified potential critical process parameters (CPPs) and their impact on the CQAs. These CPPs were prioritized using a process failure mode, effects, and criticality analysis and their critical impact on the CQAs was experimentally confirmed using a statistical design of experiments. Spray rate, atomization air pressure, and air flow rate were identified as CPPs. Coating amount and content of polysorbate 65 in the coating formulation were identified as critical material attributes. A hazard and critical control points analysis was applied to define control strategies at the critical process points. A fault tree analysis evaluated causes for potential process failures. We successfully demonstrated that a standardized quality risk management approach optimizes the product development sustainability and supports the regulatory aspects.

  3. Oxidant Status following Cardiac Surgery with Phosphorylcholine-Coated Extracorporeal Circulation Systems

    Science.gov (United States)

    Kaya, Ayşem

    2016-01-01

    Introduction. Extracorporeal circulation (ECC) related systemic oxidative stress is a well-known entity but the underlying mechanisms are not clearly described. Our aim was to investigate the relation between the oxidative stress indices, inflammatory markers, and phosphorylcholine-coated (PCC) ECC systems. Patients and Methods. Thirty-two consecutive coronary artery bypass grafting (CABG) cases were randomly assigned to Group I (PCC, n = 18) and Group II (noncoated, n = 14) ECC circuits. Total Antioxidant Status (TAS), Total Oxidant Status (TOS), Tumor Necrosis Factor-α (TNF-α), Interleukin-1β (IL-β), Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-10 (IL-10), and Procalcitonin (PCT) levels were measured at 5 different time points. The association between the oxidative indices levels and PCC system used was analyzed. Results. In Group I TOS and TAS statuses were increased at T1, T2, T3, and T4, while IL-10 and TNF-α levels accompanied those raises only at T2 (Group I-Group II, 4.73 ± 2.04 versus 2.79 ± 0.63, p = 0.002, and 30.56 ± 8.11 versus 23.97 ± 7.8, p = 0.031, resp.). In contrast, mean TAS and TOS levels were similar to baseline at all time points in Group II but IL-6 and IL-8 levels were increased at T2 (Group I-Group II, 16.84 ± 5.63 versus 44.81 ± 17.0, p = 0.001, and 38.88 ± 9.8 versus 46.14 ± 9.25, p = 0.038, resp.). Conclusion. Even coated ECC systems are still incapable of attenuating the inflammatory response to cardiopulmonary bypass (CPB). PMID:27994711

  4. Electrical and structural characterisation of nanostructured titania coatings deposited on interdigitated electrode system

    Energy Technology Data Exchange (ETDEWEB)

    Milanovic, Marija, E-mail: majam@uns.ac.rs [Department of Materials Engineering, Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad (Serbia); Stojanovic, Goran [Department of Power, Electronics and Telecommunications Engineering, Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovica 6, 21000 Novi Sad (Serbia); Nikolic, Ljubica M. [Department of Materials Engineering, Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad (Serbia); Radovanovic, Milan; Skoric, Branko; Miletic, Aleksandar [Department of Power, Electronics and Telecommunications Engineering, Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovica 6, 21000 Novi Sad (Serbia)

    2011-10-17

    Highlights: {yields} La/TiO{sub 2} and Nb/TiO{sub 2} nanocrystalline coatings as interdigitated electrode system for sensors. {yields} A method for the computation of conductivity and relative permittivity was proposed. {yields} Nb causes an increase of electrical properties, while La has the opposite effect. - Abstract: This paper presents the electrical properties of La- and Nb-doped nanostructured titanium dioxide (TiO{sub 2}) thin coatings deposited on the alumina substrate with gold electrodes in the interdigitated form to obtain appropriate devices for sensor application. Electrical parameters such as conductivity {sigma} and permittivity {epsilon} were calculated using measured values of phase angle {theta}{sub m}, capacitance C{sub m} and resistance R{sub m}. These values were measured using an HP-4194A Impedance/Gain-Phase Analyzer with a Z-probe in the frequency range from 10{sup 3} Hz to 10{sup 8} Hz. The measured results showed that with addition of 2, 4 or 6 at% of lanthanum, conductivity and permittivity of analysed samples are decreasing, whereas the addition of niobium in the same percentage follows the opposite trend.

  5. Automated MALDI Matrix Coating System for Multiple Tissue Samples for Imaging Mass Spectrometry

    Science.gov (United States)

    Mounfield, William P.; Garrett, Timothy J.

    2012-03-01

    Uniform matrix deposition on tissue samples for matrix-assisted laser desorption/ionization (MALDI) is key for reproducible analyte ion signals. Current methods often result in nonhomogenous matrix deposition, and take time and effort to produce acceptable ion signals. Here we describe a fully-automated method for matrix deposition using an enclosed spray chamber and spray nozzle for matrix solution delivery. A commercial air-atomizing spray nozzle was modified and combined with solenoid controlled valves and a Programmable Logic Controller (PLC) to control and deliver the matrix solution. A spray chamber was employed to contain the nozzle, sample, and atomized matrix solution stream, and to prevent any interference from outside conditions as well as allow complete control of the sample environment. A gravity cup was filled with MALDI matrix solutions, including DHB in chloroform/methanol (50:50) at concentrations up to 60 mg/mL. Various samples (including rat brain tissue sections) were prepared using two deposition methods (spray chamber, inkjet). A linear ion trap equipped with an intermediate-pressure MALDI source was used for analyses. Optical microscopic examination showed a uniform coating of matrix crystals across the sample. Overall, the mass spectral images gathered from tissues coated using the spray chamber system were of better quality and more reproducible than from tissue specimens prepared by the inkjet deposition method.

  6. Inulin-based polymer coated SPIONs as potential drug delivery systems for targeted cancer therapy.

    Science.gov (United States)

    Scialabba, C; Licciardi, M; Mauro, N; Rocco, F; Ceruti, M; Giammona, G

    2014-11-01

    This paper deal with the synthesis and characterization of PEGylated squalene-grafted-inulin amphiphile capable of self-assembling and self-organizing into nanocarriers once placed in aqueous media. It was exploited as coating agent for obtaining doxorubicin loaded superparamagnetic iron oxide nanoparticles (SPIONs) endowed with stealth like behavior and excellent physicochemical stability. Inulin was firstly modified in the side chain with primary amine groups, followed in turn by conjugation with squalenoyl derivatives through common amidic coupling agents and PEGylation by imine linkage. Polymer coated SPIONs were so obtained by spontaneous self-assembling of inulin copolymer onto magnetite surface involving hydrophobic-hydrophobic interactions between the metallic core and the squalene moieties. The system was characterized in terms of hydrodynamic radius, zeta potential, shape and drug loading capacity. On the whole, the stealth-like shell stabilized the suspension in aqueous media, though allowing the release of the doxorubicin loaded in therapeutic range. The cytotoxicity profile on cancer (HCT116) cell line and in vitro drug uptake were evaluated both with and without an external magnetic field used as targeting agent and uptake promoter, displaying that magnetic targeting implies advantageous therapeutic effects, that is amplified drug uptake and increased anticancer activity throughout the tumor mass.

  7. Pyrolytic carbon-coated stainless steel felt as a high-performance anode for bioelectrochemical systems.

    Science.gov (United States)

    Guo, Kun; Hidalgo, Diana; Tommasi, Tonia; Rabaey, Korneel

    2016-07-01

    Scale up of bioelectrochemical systems (BESs) requires highly conductive, biocompatible and stable electrodes. Here we present pyrolytic carbon-coated stainless steel felt (C-SS felt) as a high-performance and scalable anode. The electrode is created by generating a carbon layer on stainless steel felt (SS felt) via a multi-step deposition process involving α-d-glucose impregnation, caramelization, and pyrolysis. Physicochemical characterizations of the surface elucidate that a thin (20±5μm) and homogenous layer of polycrystalline graphitic carbon was obtained on SS felt surface after modification. The carbon coating significantly increases the biocompatibility, enabling robust electroactive biofilm formation. The C-SS felt electrodes reach current densities (jmax) of 3.65±0.14mA/cm(2) within 7days of operation, which is 11 times higher than plain SS felt electrodes (0.30±0.04mA/cm(2)). The excellent biocompatibility, high specific surface area, high conductivity, good mechanical strength, and low cost make C-SS felt a promising electrode for BESs.

  8. Self-lubricant nanocomposite hard coatings in Ti-Al-N-C system

    Institute of Scientific and Technical Information of China (English)

    Y. Z. Huang; M. Stueber; P. Barna; J.M. Rodenburg

    2004-01-01

    An ambitious objective in the development of self-lubricating wear-resistant coatings is to make use of lubricious phases such as graphite, amorphous carbon or MoS2 incorporated into coatings. A series of (Ti,Al)(N,C)coatings with different carbon contents (0 -28 %, mole fraction) were deposited by reactive magnetron sputtering of TiAl in a mixture of Ar, N2 and CH4 gases. The microstructure and constitution of these coatings were investigated using EPMA, AFM, XPS, (HR)TEM, Raman spectroscopy and X-ray diffraction. Starting from a pure TiAlN coating significant changes in the microstructure of the coatings were observed dependent on the carbon concentration. Under optimum conditions nanocomposite coatings with a structure of a coexisting metastable hard, nanocrystalline fcc (Ti,Al)(N,C) phase and an amorphous carbon phase were deposited. The localization of an amorphous carbon phase was shown by HRTEM.

  9. Effect of Y2O3 stabilized ZrO2 coating with tri-model structure on bi-layered thermally grown oxide evolution in nano thermal barrier coating systems at elevated temperatures

    Institute of Scientific and Technical Information of China (English)

    Mohammadreza Daroonparvar; Muhamad Azizi Mat Yajid; Noordin Mohd Yusof; Hamid Reza Bakhsheshi-Rad; Z Valefi; Esah Hamzah

    2014-01-01

    Bi-layered thermally grown oxide (TGO) layer plays a major role in the spallation of Y2O3 stabilized ZrO2 (YSZ) layer form the bond coat in the thermal barrier coating (TBC) systems during oxidation. On the other hand, bi-layered TGO formation and growth in the TBC systems with nanostructured YSZ have not been deeply investigated during cyclic oxidation. Hence, Inconel 738/NiCrAlY/normal YSZ and Inconel 738/NiCrAlY/nano YSZ systems were pre-oxidized at 1000 °C and then subjected to cyclic oxidation at 1150 °C. According to microstructural observations, nanostructured YSZ layer over the bond coat should have less mi-cro-cracks and pinholes, due to the compactness of the nanostructure and the presence of nano zones that resulted in lower O infiltration into the nanothermal barrier coating system, formation of thinner and nearly continuous mono-layered thermally grown oxide on the bond coat during pre-oxidation, lower spinels formation at the Al2O3/YSZ interface and finally, reduction of bi-layered thermally grown oxide thickness during cyclic oxidation. It was found that pre-heat treatment and particularly coating microstructure could influence microstructural evolution (bi-layered TGO thickness) and durability of thermal barrier coating systems during cyclic oxidation.

  10. Evaluation of long-term corrosion durability and self-healing ability of scratched coating systems on carbon steel in a marine environment

    Science.gov (United States)

    Zhao, Xia; Chen, Changwei; Xu, Weichen; Zhu, Qingjun; Ge, Chengyue; Hou, Baorong

    2016-09-01

    Defects in protective-coating systems on steel surfaces are inevitable in practical engineering applications. A composite coating system, including a primer, middle coat and topcoat, were used to protect carbon steel from corrosion in a marine environment. Two environmental additives, glass fibers and thiourea, were applied in the middle coat to modify the coating system. The long-term corrosion durability and self-healing ability of the scratched coating system were evaluated by multiple methods. Results of the electrochemical technologies indicated that the coating system that contained 0.5 wt.% fibers and 0.5 wt.% thiourea presented good corrosion protection and self-healing for carbon steel when immersed in 3.5% NaCl for 120 d. Evolution of localized corrosion factors with time, as obtained from the current distribution showed that fibers combined with thiourea could inhibit the occurrence of local corrosion in scratched coating systems and retarded the corrosion development significantly. Surface characterization suggested that adequate thiourea could be absorbed uniformly on fibers for a long time to play an important role in protecting the carbon steel. Finally, schematic models were established to demonstrate the action of fibers and thiourea on the exposed surface of the carbon steel and the scratched coating system in the entire deterioration process.

  11. The Hull Method for Selecting the Number of Common Factors

    Science.gov (United States)

    Lorenzo-Seva, Urbano; Timmerman, Marieke E.; Kiers, Henk A. L.

    2011-01-01

    A common problem in exploratory factor analysis is how many factors need to be extracted from a particular data set. We propose a new method for selecting the number of major common factors: the Hull method, which aims to find a model with an optimal balance between model fit and number of parameters. We examine the performance of the method in an…

  12. "Keisri hull" pürib taas filmiks

    Index Scriptorium Estoniae

    2008-01-01

    Eesti Filmi Sihtasutus otsustas anda arendustoetust mängufilmidele "Keisri hull" (režissöör Peeter Simm, arendaja Lege Artis Film), "Rahad ette" (režissöör Jaak Kilmi, arendaja Eetriüksus), "Öölendurid" (režissöör Peeter Urbla, arendaja Exitfilm)

  13. "Keisri hull" pürib taas filmiks

    Index Scriptorium Estoniae

    2008-01-01

    Eesti Filmi Sihtasutus otsustas anda arendustoetust mängufilmidele "Keisri hull" (režissöör Peeter Simm, arendaja Lege Artis Film), "Rahad ette" (režissöör Jaak Kilmi, arendaja Eetriüksus), "Öölendurid" (režissöör Peeter Urbla, arendaja Exitfilm)

  14. The fundamental formulas for vertices of convex hull

    Directory of Open Access Journals (Sweden)

    Md. Kazi Salimullah

    2013-07-01

    Full Text Available This paper represents four formulas for solution of convex hull problem. It aims to analyze how many points are vertices out of total input points, how many vertices lie on a horizontal or vertical lines, position of vertices and number of vertices on lower and higher lines(horizontal or vertical.

  15. Morphologically intelligent underactuated robot for underwater hull cleaning

    DEFF Research Database (Denmark)

    Souto, Daniel; Faina, Andres; López-Peña, Fernando

    2015-01-01

    in the use of the chemicals that are usually employed to prevent the growth of marine life on the hull and which are generally harmful to the environment. The robot described in this paper is an underactuated morphologically adapted robot that through an appropriate morphology and making use of the forces...

  16. CFD simulation on Kappel propeller with a hull wake field

    DEFF Research Database (Denmark)

    Shin, Keun Woo; Andersen, Poul; Møller Bering, Rasmus

    2013-01-01

    -water characteristics. The hull wake field is simulated without the propeller flow to check whether it is preserved at the propeller plane or not. Propeller flow simulations are made with mean axial wake varying only along the radius (i.e. circumferentially uniform), whole axial wake and upstream transverse wake...

  17. 46 CFR 154.170 - Outer hull steel plating.

    Science.gov (United States)

    2010-10-01

    ... American Bureau of Shipping published in “Rules for Building and Classing Steel Vessels” 1981. (b) Along... 46 Shipping 5 2010-10-01 2010-10-01 false Outer hull steel plating. 154.170 Section 154.170... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment...

  18. Water Pressure Distribution on a Flying Boat Hull

    Science.gov (United States)

    Thompson, F L

    1931-01-01

    This is the third in a series of investigations of the water pressures on seaplane floats and hulls, and completes the present program. It consisted of determining the water pressures and accelerations on a Curtiss H-16 flying boat during landing and taxiing maneuvers in smooth and rough water.

  19. Convex Hull Abstraction in Specialisation of CLP Programs

    DEFF Research Database (Denmark)

    Peralta, J.C.; Gallagher, John Patrick

    2003-01-01

    We introduce an abstract domain consisting of atomic formulas constrained by linear arithmetic constraints (or convex hulls). This domain is used in an algorithm for specialization of constraint logic programs. The algorithm incorporates in a single phase both top-down goal directed propagation a...

  20. Effects of Geometry on the Steady Performance of Planing Hulls

    DEFF Research Database (Denmark)

    Wagner, M. K.; Andersen, Poul

    2003-01-01

    is applied to practical hull forms with chines spray rails and with varying deadrise over the length of the boat. The deadrise variation has a large influence on lift and drag. For a design situation, where the total lift and centre of effort is given, the influence on the total drag is less due to change...

  1. Protective Coatings

    Science.gov (United States)

    1980-01-01

    General Magnaplate Corporation's pharmaceutical machine is used in the industry for high speed pressing of pills and capsules. Machine is automatic system for molding glycerine suppositories. These machines are typical of many types of drug production and packaging equipment whose metal parts are treated with space spinoff coatings that promote general machine efficiency and contribute to compliance with stringent federal sanitation codes for pharmaceutical manufacture. Collectively known as "synergistic" coatings, these dry lubricants are bonded to a variety of metals to form an extremely hard slippery surface with long lasting self lubrication. The coatings offer multiple advantages; they cannot chip, peel or be rubbed off. They protect machine parts from corrosion and wear longer, lowering maintenance cost and reduce undesired heat caused by power-robbing friction.

  2. Development Status and Performance Comparisons of Environmental Barrier Coating Systems for SiCSiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming; Harder, Bryan

    2016-01-01

    Environmental barrier coatings (EBC) and SiCSiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft turbine engine systems, because of their ability to significantly increase engine operating temperatures, reduce engine weight and cooling requirements. This paper presents current NASA EBC-CMC development emphases including: the coating composition and processing improvements, laser high heat flux-thermal gradient thermo-mechanical fatigue - environmental testing methodology development, and property evaluations for next generation EBC-CMC systems. EBCs processed with various deposition techniques including Plasma Spray, Electron Beam - Physical Vapor Deposition, and Plasma Spray Physical Vapor Deposition (PS-PVD) will be particularly discussed. The testing results and demonstrations of advanced EBCs-CMCs in complex simulated engine thermal gradient cyclic fatigue, oxidizing-steam and CMAS environments will help provide insights into the coating development strategies to meet long-term engine component durability goals.

  3. Corrosion Resistance of Zn and Cu Coated Steel Pipes as a Substitute for Cu Pipe in an Air Conditioner System

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jae Gyeong; Park, Chan Jin; Hong, Sung Kil [Chonnam National University, Gwangju (Korea, Republic of)

    2009-02-15

    We investigated the corrosion resistance of Zn and Cu coated steel pipes as a substitute for Cu pipe in an air-conditioner system. In addition, the galvanic corrosion tendency between two dissimilar metal parts was studied. The corrosion resistance of the Cu electroplated steel was similar to that of Cu, while the corrosion rate of the Zn electro-galvanized and the galvalume (Zn-55 % Al) coated steels was much higher and not suitable for Cu substitute in artificial sea water and acidic rain environments. Furthermore, the galvanic difference between Cu electroplated steel and Cu was so small that the Cu coated steel pipe can be used as a substitute for Cu pipe in an air-conditioner system.

  4. Aerodynamic Characteristics of Three Deep-Stepped Planing-Tail Flying-Boat Hulls

    Science.gov (United States)

    Riebe, John M.; Naeseth, Rodger L.

    1947-01-01

    An investigation was made in the Langley 300 MPH 7- by 10-foot tunnel to determine the aerodynamic characteristics of three deep-stepped planing-tail flying-boat hulls differing only in the amount of step fairing. The hulls were derived by increasing the unfaired step depth of a planing-tail hull of a previous aerodynamic investigation to a depth about 92 percent of the hull beam. Tests were also made on a transverse-stepped hull with an extended afterbody for the purpose of comparison and in order to extend and verify the results of a previous investigation. The investigation indicated that the extended afterbody hull had a minimum drag coefficient about the same as a conventional hull, 0.0066, and an angle-of-attack range for minimum drag coefficient of 0.0057 which was 14 percent less than the transverse stepped hull with extended afterbody; the hulls with step fairing had up to 44 percent less minimum drag coefficient than the transverse-stepped hull, or slightly more drag than a streamlined body having approximately the same length and volume. Longitudinal and lateral instability varied little with step fairing and was about the same as a conventional hull.

  5. Optimization of Wigley Hull Form in order to Ensure the Objective Functions of the Seakeeping Performance

    Institute of Scientific and Technical Information of China (English)

    Hassan Bagheri; Hassan Ghassemi

    2014-01-01

    The research performed in this paper was carried out to investigate the computational procedure to design seakeeping optimized ship hull form. To reach the optimized hull form, four stages should be done, which consists of: generate alternative hull form, seakeeping calculations, objective functions and optimization techniques. There are many parameters that may be determined in ship hull form optimization. This paper deals with developed strip theory for determining the seakeeping performance, genetic algorithm (GA) as optimization method, high order equations for curve fitting of the hull form and finally reaching to the minimum bow vertical motion in regular head waves. The Wigley hull is selected as an initial hull and carried to be optimized. Two cases are considered. For the first case, the only form coefficients of the hull (CB, CM, CW, CP) are changed and main dimensions (L, B, T) are fixed. In the second case both hull form and main dimensions are varied simultaneously. Finally, optimized hull form and its seakeeping performances are presented. The results of optimization procedure demonstrate that the optimized hull forms yield a reduction in vertical motion and acceleration.

  6. Diffusion Coatings for Corrosion-Resistant Components in Coal Gasification Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gopala N. Krishnan; Ripudaman Malhotra; Esperanza Alvarez; Kai-Hung Lau; Jordi Perez Mariano; Angel Sanjurjo

    2006-09-30

    Heat-exchangers, particle filters, turbines, and other components in integrated coal gasification combined cycle system must withstand the highly sulfiding conditions of the high temperature coal gas over an extended period of time. The performance of components degrades significantly with time unless expensive high alloy materials are used. Deposition of a suitable coating on a low-cost alloy may improve its resistance to such sulfidation attack, and decrease capital and operating costs. The alloys used in the gasifier service include austenitic and ferritic stainless steels, nickel-chromium-iron alloys, and expensive nickel-cobalt alloys. The primary activity this period was preparation and presentation of the findings on this project at the Twenty-Third annual Pittsburgh Coal Conference. Dr. Malhotra attended this conference and presented a paper. A copy of his presentation constitutes this quarterly report.

  7. Implementing an emergency medical services system in Kathmandu, Nepal: a model for "white coat diplomacy".

    Science.gov (United States)

    Walker, Rebecca; Auerbach, Paul S; Kelley, Benjamin V; Gongal, Rajesh; Amsalem, David; Mahadevan, Swaminatha

    2014-09-01

    Wilderness medicine providers often visit foreign lands, where they come in contact with medical situations that are representative of the prevailing healthcare issues in the host countries. The standards of care for matters of acute and chronic care, public health, and crisis intervention are often below those we consider to be modern and essential. Emergency medical services (EMS) is an essential public medical service that is often found to be underdeveloped. We describe our efforts to support development of an EMS system in the Kathmandu Valley of Nepal, including training the first-ever class of emergency medical technicians in that country. The purpose of this description is to assist others who might attempt similar efforts in other countries and to support the notion that an effective approach to improving foreign relations is assistance such as this, which may be considered a form of "white coat diplomacy."

  8. On-Chip Bondwire Magnetics with Ferrite-Epoxy Glob Coating for Power Systems on Chip

    Directory of Open Access Journals (Sweden)

    Jian Lu

    2008-01-01

    Full Text Available A novel concept of on-chip bondwire inductors and transformers with ferrite epoxy glob coating is proposed to offer a cost effective approach realizing power systems on chip (SOC. We have investigated the concept both experimentally and with finite element modeling. A Q factor of 30–40 is experimentally demonstrated for the bondwire inductors which represents an improvement by a factor of 3–30 over the state-of-the-art MEMS micromachined inductors. Transformer parameters including self- and mutual inductance and coupling factors are extracted from both modeled and measured S-parameters. More importantly, the bondwire magnetic components can be easily integrated into SOC manufacturing processes with minimal changes and open enormous possibilities for realizing cost-effective, high-current, high-efficiency power SOCs.

  9. Carbon-Dot-Coated Alginate Beads as a Smart Stimuli-Responsive Drug Delivery System.

    Science.gov (United States)

    Majumdar, Sristi; Krishnatreya, Gargee; Gogoi, Neelam; Thakur, Debajit; Chowdhury, Devasish

    2016-12-21

    In this work, we report a smart stimuli-responsive drug delivery system (DDS) that can release drug depending upon the amount of pathogen (MRSA) present in the target. A greater amount of MRSA in the system will lead to more release of drug and vice versa. Carbon-dot-coated novel alginate beads (CA-CD) exhibiting superior stability was successfully used as smart drug delivery vehicle. Garlic extract (GE), which contains allicin, was taken as model drug system to demonstrate the phenomena. It was observed that GE loading was 19 and 78% with CA and CA-CD, respectively. CA-CD-GE shows pH-dependent controlled drug release, which results in increased therapeutic efficiency. CA-CD-GE is not only stimuli responsive but also a controlled drug release system as it releases drug according to the pathogen concentration (MRSA). All the three factors viz. drug release, MRSA concentration and pH of the medium are interdependent as when the cell divides, it produces secondary metabolites that lead to the decrease in pH of the medium. The drop in the pH value triggers drug release from the beads. And the effect of the drug is reflected by the MRSA cell death. Hence, we demonstrate a smart stimuli responsive DDS. However, such DDS will be useful in cases where increased amount of pathogen in the system will lead to reduction in pH.

  10. Environmentally benign sol-gel antifouling and foul-releasing coatings.

    Science.gov (United States)

    Detty, Michael R; Ciriminna, Rosaria; Bright, Frank V; Pagliaro, Mario

    2014-02-18

    Biofouling on ships and boats, characterized by aquatic bacteria and small organisms attaching to the hull, is an important global issue, since over 80000 tons of antifouling paint is used annually. This biofilm, which can form in as little as 48 hours depending on water temperature, increases drag on watercraft, which greatly reduces their fuel efficiency. In addition, biofouling can lead to microbially induced corrosion (MIC) due to H2S formed by the bacteria, especially sulfate-reducing bacteria. When the International Maritime Organization (IMO) international convention banned the use of effective but environmentally damaging coatings containing tributyl tin in 2008, the development of clean and effective antifouling systems became more important than ever. New nonbiocidal coatings are now in high demand. Scientists have developed new polymers, materials, and biocides, including new elastomeric coatings that they have obtained by improving the original silicone (polydimethylsiloxane) formulation patented in 1975. However, the high cost of silicones, especially of fluoropolymer-modified silicones, has generally prevented their large-scale diffusion. In 2009, traditional antifouling coatings using cuprous oxide formulated in copolymer paints still represented 95% of the global market volume of anti-fouling paints. The sol-gel nanochemistry approach to functional materials has emerged as an attractive candidate for creating low fouling surfaces due to the unique structure and properties of silica-based coatings and of hybrid inorganic-organic silicas in particular. Sol-gel formulations easily bind to all types of surfaces, such as steel, fiberglass, aluminum, and wood. In addition, they can cure at room temperature and form thin glassy coatings that are markedly different from thick silicone elastomeric foul-releasing coatings. Good to excellent performance against biofouling, low cure temperatures, enhanced and prolonged chemical and physical stability, ease of

  11. Polyelectrolyte Multilayer Film Coated Silver Nanorods: An Effective Carrier System for Externally Activated Drug Delivery

    Science.gov (United States)

    Paramasivam, Gokul; Sharma, Varsha; Sundaramurthy, Anandhakumar

    2017-08-01

    Nanoparticle anisotropy offers unique functions and features in comparison with spherical nanoparticles (NPs) and makes anisotropic nanoparticles (ANPs) promising candidates in applications like drug delivery, imaging, biosensing and theranostics. Presence of surface active groups (e.g. amine, and carboxylate groups) on their surface provides binding sites for ligands or other biomolecules, and hence, this could be targeted for specific part or cells in our body. In the quest of such surface modification, functionalization of ANPs along Layer-by-Layer (LbL) coating of oppositely charged polyelectrolytes (PE) reduces cellular toxicity and promotes easy encapsulation of drugs. In this work, we report the silver nanorods (AgNRs) synthesis by adsorbate directed synthetic approach using cetyltrimethyl ammonium bromide (CTAB). The formed ANPs is investigated by scanning electron microscopy (SEM) and UV-Visible (UV-Vis) spectroscopy revealing the shaping of AgNRs of 3-16 nm aspect ratio with some presence of triangles. These NRs were further coated with bio polymers of chitosan (CH) and dextran sulphate (DS) through LbL approach and used for encapsulation of water soluble anti-bacterial drugs like ciprofloxacin hydrochloride (CFH). The encapsulation of drugs and profiles of drug release were investigated and compared to that of spherical silver nanoparticles (AgNPs). The added advantages of the proposed drug delivery system (DDS) can be externally activated to release the loaded drug and used as contrast agents for biological imaging under exposure to NIR light. Such system shows unique and attractive characteristics required for drug delivery and bioimaging thus offering the scope for further development as theranostic material.

  12. Study on practical application of a longitudinal hull strength theory considering camber in cross section; Yokodanmen no sori wo koryoshita sentai tate kyodo riron no jitsuyoka ni kansuru kenkyu. 2

    Energy Technology Data Exchange (ETDEWEB)

    Nose, M.; Suzuki, K.; Furuno, H. [Nagasaki Institute of Applied Science, Nagasaki (Japan); Suzuki, K.

    1997-10-01

    Discussions were given on practical application of a stress analyzing method for thin-wall deformed cross-sectional beam considering cross section camber in longitudinal bending. The non-static calculation method described in the previous report can be applied to a box-type cross section having multi-connected cells, bulk cargo transport vessels and container ships with dual hull structure, and oil tankers with dual hull structure of medium size. The calculation method was capable of achieving remarkable enhancement in efficiency over that of conventional calculation methods. The present study is intended to make the method applicable also to multi-connected cross section shapes having more than one longitudinal partitions as used in dual hull VLCC and ULCC. As a result, an expanded non-static calculation system was developed, which has introduced into the conception described in the previous report a new conception of triple point and independent start point members. As a result of applying the method to dual hull bulk cargo transport vessels, container ships, dual hull oil tankers of medium size, VLCC and ULCC, it was verified that the system operated properly. Remarkable efficiency improvement has been made possible as compared with conventional analysis methods applied to individual ships. The system is capable of automatic calculation, and makes possible the practical application of the hull strength theory considering cross section camber. 3 refs., 10 figs., 1 tab.

  13. Use of coated fabric membranes for facade and roof systems of steel constructions

    OpenAIRE

    Lavrič, Anja

    2011-01-01

    The thesis is divided into three parts. In the first part (chapters 2 to 7), types of architectural membrane structures from coated fabrics are presented, different types of coated fabrics and their composition is described, welding procedures for membranes from coated fabrics are shown, and physical and mechanical characteristics of these membranes are given, including laboratory tests descriptions of individual characteristics. In the second part of the thesis (chapter 8), we are discussing...

  14. Novel process for trivalent chromium plating in chloride system and properties of obtained chromium coatings%氯化物体系三价铬电镀新工艺及其镀层性能

    Institute of Scientific and Technical Information of China (English)

    赖奂汶; 郭崇武

    2013-01-01

    开发了Trich-6861氯化物体系三价铬电镀新工艺.通过赫尔槽试验测得不同电流密度下的镀铬速率维持在0.077~0.181 μm/min,且不随电镀时间延长而改变.镀层厚度在0.4 μm以上,表面呈蓝白色,光滑、无裂纹,中性盐雾试验120 h不变色,恒定湿热试验、冷热冲击试验、人造汗液测试和抗化学污染测试均合格.生产实践表明,该工艺镀液性能稳定,操作简单,便于维护,顾客满意度较高.%A novel Trich-6861 process for trivalent chromium plating in chloride system was developed. The deposition rate of the process measured by Hull cell test is 0.077-0.181 μm/min at different current densities, invariable with the extending of plating time. The chromium coating has a thickness of 0.4 μm or above, with blue-white, smooth, and crack-free surface, does not tarnish after neutral salt spray test for 120 h, and can pass the steady-state damp heat test, cold-heat shock test, artificial sweat test, and chemical contamination test. The production practice showed that the plating process has advantages of high bath stability, simple operation, and easy maintenance, and thus has earned a high customer satisfaction.

  15. Phenol-formaldehyde intumescent coating composition and coating prepared therefrom

    Science.gov (United States)

    Salyer, Ival O. (Inventor); Fox, Bernard L. (Inventor)

    1986-01-01

    Intumescent coatings which form a thick, uniform, fine celled, low density foam upon exposure to a high intensity heat flux or flame are disclosed, the invention coatings comprise phenolic resin prepolymer containing a blowing agent and a nucleating agent; in the preferred embodiments the coatings also contains a silicone surfactant, the coatings are useful in thermal and fire protection systems.

  16. Preparation and characterization of 6-mercaptopurine-coated magnetite nanoparticles as a drug delivery system

    Directory of Open Access Journals (Sweden)

    Dorniani D

    2013-09-01

    . By MTT assay, the FCMP nanocomposite was shown not to be toxic to a normal mouse fibroblast cell line. Conclusion: Iron oxide coated with chitosan containing 6-mercaptopurine prepared using a coprecipitation method has the potential to be used as a controlled-release formulation. These nanoparticles may serve as an alternative drug delivery system for the treatment of cancer, with the added advantage of sparing healthy surrounding cells and tissue. Keywords: superparamagnetic nanoparticles, 6-mercaptopurine, controlled release, cytotoxicity, drug delivery

  17. Design and demonstration of a system for the deposition of atomic-oxygen durable coatings for reflective solar dynamic power system concentrators

    Science.gov (United States)

    Mcclure, Donald J.

    1988-01-01

    A system for the vacuum deposition of atomic-oxygen durable coatings for reflective solar dynamic power systems (SDPS) concentrators was designed and demonstrated. The design issues pertinent to SDPS were developed by the Government Aerospace Systems Division of the Harris Corporation and are described in NASA-CR-179489. Both design and demonstration phases have been completed. At the time of this report the deposition system was ready for coating of facets for SDPS concentrators. The materials issue relevant to the coating work were not entirely resolved. These issues can only be resolved when substrates which are comparable to those which will be used in flight hardware are available. The substrates available during the contract period were deficient in the areas of surface roughness and contamination. These issues are discussed more thoroughly in the body of the report.

  18. Residual stresses within sprayed coatings

    Institute of Scientific and Technical Information of China (English)

    JIANG Yi; XU Bin-shi; WANG Hai-dou

    2005-01-01

    Some important developments of residual stress researches for coating-based systems were studied. The following topics were included the sources of residual stresses in coatings: error analysis of Stoney's equation in the curvature method used for the measurement of coating residual stress, the modeling of residual stress and some analytical models for predicting the residual stresses in coatings. These topics should provide some important insights for the fail-safe design of the coating-based systems.

  19. Effect of storage time, thermocycling and resin coating on durability of dentin bonding systems

    Directory of Open Access Journals (Sweden)

    Seyed-Mostafa Mousavinasab

    2009-01-01

    Full Text Available Background:Along with development of different dental adhesives, concerns about hydrolytic deg-radation of the adhesive components have arisen. The purpose of this study was to evaluate the in-vitro influence of thermocycling, water storage and resin coating on the microshear bond strength of total etch and self etch adhesive systems to dentin. Methods:The superficial coronal dentin of eighty intact third molars were exposed and divided into 5 equal groups. Dental adhesives including Scotch Bond Multi Purpose (SBMP, Single Bond (SB, Clearfil SE Bond (CSE, Prompt L-Pop (PLP, and Prompt L-Pop plus Margin bond (PLPM were applied according to the manufacturers′ instructions on prepared surfaces in the study groups, respectively. Then composite cylinders were bonded and specimens were divided into two subgroups. One subgroup was stored in water for 24 hours. The second subgroup was subjected to 3000 thermocycle shocks and then was stored in 37°C water for 3 months. Finally, all teeth were subjected to the mi-croshear bond strength test. Data were analyzed using two-way ANOVA and Tukey HSD tests. One specimen similar to each subgroup was also prepared for SEM evaluation. Results:After one-day storage, the SBMP showed the highest bond strength followed by CSE, PLPM, SB and PLP. After three months storage, the highest bond strength was observed in SBMP followed by PLPM, CSE, SB, and PLP. Conclusion: SBMP showed the best bond strength while CSE represented acceptable bond durabil-ity. Resin coating on PLP improved bond strength and durability.

  20. The mucoadhesive and gastroretentive properties of hydrophobin-coated porous silicon nanoparticle oral drug delivery systems.

    Science.gov (United States)

    Sarparanta, Mirkka P; Bimbo, Luis M; Mäkilä, Ermei M; Salonen, Jarno J; Laaksonen, Päivi H; Helariutta, A M Kerttuli; Linder, Markus B; Hirvonen, Jouni T; Laaksonen, Timo J; Santos, Hélder A; Airaksinen, Anu J

    2012-04-01

    Impediments to intestinal absorption, such as poor solubility and instability in the variable conditions of the gastrointestinal (GI) tract plague many of the current drugs restricting their oral bioavailability. Particulate drug delivery systems hold great promise in solving these problems, but their effectiveness might be limited by their often rapid transit through the GI tract. Here we describe a bioadhesive oral drug delivery system based on thermally-hydrocarbonized porous silicon (THCPSi) functionalized with a self-assembled amphiphilic protein coating consisting of a class II hydrophobin (HFBII) from Trichoderma reesei. The HFBII-THCPSi nanoparticles were found to be non-cytotoxic and mucoadhesive in AGS cells, prompting their use in a biodistribution study in rats after oral administration. The passage of HFBII-THCPSi nanoparticles in the rat GI tract was significantly slower than that of uncoated THCPSi, and the nanoparticles were retained in stomach by gastric mucoadhesion up to 3 h after administration. Upon entry to the small intestine, the mucoadhesive properties were lost, resulting in the rapid transit of the nanoparticles through the remainder of the GI tract. The gastroretentive drug delivery system with a dual function presented here is a viable alternative for improving drug bioavailability in the oral route.

  1. DEMONSTRATION OF NO-VOC/NO-HAP WOOD FURNITURE COATING SYSTEM

    Science.gov (United States)

    The United States Environmental Protection Agency has contracted with AeroVironment Environmental Services, Inc. and its subcontractor, Adhesives Coating Co., to develop and demonstrate a no-VOC (volatile organic compound)/no-HAP (hazardous air pollutant) wood furniture coating s...

  2. Release of cerium dibutylphosphate corrosion inhibitors from highly filled epoxy coating systems

    NARCIS (Netherlands)

    Soestbergen, M. van; Baukh, V.; Erich, S.J.F.; Huinink, H.P.; Adan, O.C.G.

    2014-01-01

    Carcinogenic chromates are phased out as corrosion inhibitors in organic coatings, and are replaced by benign alternatives. Cerium-based compounds are excellent corrosion inhibitors in an aqueous environment. However, whether they are effective as corrosion inhibitor in an organic coating also depen

  3. Investigation into the Coating and Desensitization Effect on HNIW of Paraffin Wax/Stearic Acid Composite System

    Science.gov (United States)

    Wang, Dong-Xu; Chen, Shu-Sen; Jin, Shao-Hua; Shu, Qing-Hai; Jiang, Zhen-Ming; Shang, Feng-Qin; Li, Jin-Xin

    2016-01-01

    2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW) was bonded by fluorine rubber and then desensitized by paraffin wax (PW), stearic acid (SA), and a PW/SA composite system using an aqueous suspension method. The coating and desensitization effects of the composite systems on HNIW and the influence of the addition of SA on the mechanical properties of the coated HNIW samples were studied. In addition, the PW/SA composite solution was simulated using a molecular dynamics method, and the relationship between the desensitization effect on HNIW and the properties of the composite solution was investigated. The results showed that the PW/SA composite system, of which the desensitization effect on HNIW was between those of the two desensitizers, could effectively coat HNIW and that the composite solution had the most stable and well-distributed state when using benzene as solvent with the mass ratio of PW/SA equal to 7/3 or 3/7, thus resulting in the best desensitization effect on HNIW. Moreover, the addition of stearic acid was successful in enhancing the mechanical properties of the coated HNIW samples.

  4. Functionally gradient materials for thermal barrier coatings in advanced gas turbine systems

    Energy Technology Data Exchange (ETDEWEB)

    Banovic, S.W.; Barmak, K.; Chan, H.M. [Lehigh Univ., Bethlehem, PA (United States)] [and others

    1995-10-01

    New designs for advanced gas turbine engines for power production are required to have higher operating temperatures in order to increase efficiency. However, elevated temperatures will increase the magnitude and severity of environmental degradation of critical turbine components (e.g. combustor parts, turbine blades, etc{hor_ellipsis}). To offset this problem, the usage of thermal barrier coatings (TBCs) has become popular by allowing an increase in maximum inlet temperatures for an operating engine. Although thermal barrier technology is over thirty years old, the principle failure mechanism is the spallation of the ceramic coating at or near the ceramic/bond coat interface. Therefore, it is desirable to develop a coating that combines the thermal barrier qualities of the ceramic layer and the corrosion protection by the metallic bond coat without the detrimental effects associated with the localization of the ceramic/metal interface to a single plane.

  5. Study on the methods of precision controlling for the manufacture of hull curvature sections

    Institute of Scientific and Technical Information of China (English)

    LIU Yu-jun; HU Ri-qiang; DENG Yan-ping

    2006-01-01

    The precision controlling technology is a key step for the modern ship construction, with the precision controlling of the ship-hull curvature as one of bottlenecks in shipbuilding, where the initial is to present a compensation value for the ship-hull plate precisely. The compensation value of the curvature plate is composed of two parts: the construction compensation, which results in the process of heating construction of curvature plate, and the assembling compensation, which results in welding ribbed stiffeners onto the curvature plate. Based on the developed computation system for the local contraction value, this paper presents a method to establish the experimented samples for the assembling compensation by means of numerical experiments, and another method to establish the practical mathematical model for the construction compensation of curvature plate. Furthermore, it introduces the experimental measuring method for the assembling compensation of the curvature plate, based on which the related database system has been developed. Numerical examples are analyzed to demonstrate the process to establish mathematical model for the assembling compensation values.

  6. Precise Morphology Control and Continuous Fabrication of Perovskite Solar Cells Using Droplet-Controllable Electrospray Coating System.

    Science.gov (United States)

    Hong, Seung Chan; Lee, Gunhee; Ha, Kyungyeon; Yoon, Jungjin; Ahn, Namyoung; Cho, Woohyung; Park, Mincheol; Choi, Mansoo

    2017-03-08

    Herein, we developed a novel electrospray coating system for continuous fabrication of perovskite solar cells with high performance. Our system can systemically control the size of CH3NH3PbI3 precursor droplets by modulating the applied electrical potential, shown to be a crucial factor for the formation of perovskite films. As a result, we have obtained pinhole-free and large grain-sized perovskite solar cells, yielding the best PCE of 13.27% with little photocurrent hysteresis. Furthermore, the average PCE through the continuous coating process was 11.56 ± 0.52%. Our system demonstrates not only the high reproducibility but also a new way to commercialize high-quality perovskite solar cells.

  7. Effects of feeding hull-less barley on production performance, milk fatty acid composition, and nutrient digestibility of lactating dairy cows.

    Science.gov (United States)

    Yang, Y; Ferreira, G; Teets, C L; Corl, B A; Thomason, W E; Griffey, C A

    2017-03-16

    The objectives of this study were to evaluate production performance, milk fatty acid composition, and nutrient digestibility in high-producing dairy cows consuming diets containing corn and hull-less barley (cultivar Amaze 10) in different proportions as the grain source. Eight primiparous and 16 multiparous Holstein cows were assigned to 1 of 4 diets in a replicated 4 × 4 Latin square design with 21-d periods. Cows were fed once daily (1200 h) by means of a Calan gate system (American Calan Inc., Northwood, NH). All diets contained ∼20% grain (dry matter basis). Treatments consisted of 100% corn (0B), 67% corn and 33% hull-less barley (33B), 33% corn and 67% hull-less barley (67B), and 100% hull-less barley (100B) as the grain sources. Total-tract nutrient digestibility was estimated using lanthanum chloride (LaCl3) as an external marker. Dry matter intake differed quadratically among treatments, being lowest for 67B and highest for 0B and 100B. Feeding hull-less barley did not affect milk yield, and milk fat concentration differed cubically among treatments. The cubic response was attributed to the higher milk fat concentration observed for the diet containing 67B. Neither the concentrations in milk of protein and lactose nor the yields of protein and lactose differed among treatments. The proportion of de novo synthesized fatty acids in milk did not differ among treatments. The apparent total-tract digestibility of dry matter, crude protein, and neutral detergent fiber did not differ among treatments. Although a quadratic effect was observed, starch digestibility was minimally affected by treatments. In conclusion, this study indicates that hull-less barley grain is as good as corn grain as an energy source when formulating diets for high-producing dairy cows.

  8. Bubbles versus biofilms: a novel method for the removal of marine biofilms attached on antifouling coatings using an ultrasonically activated water stream

    Science.gov (United States)

    Salta, M.; Goodes, L. R.; Maas, B. J.; Dennington, S. P.; Secker, T. J.; Leighton, T. G.

    2016-09-01

    The accumulation of marine organisms on a range of manmade surfaces, termed biofouling, has proven to be the Achilles’ heel of the shipping industry. Current antifouling coatings, such as foul release coatings (FRCs), only partially inhibit biofouling, since biofilms remain a major issue. Mechanical ship hull cleaning is commonly employed to remove biofilms, but these methods tend to damage the antifouling coating and often do not result in full removal. Here, we report the effectiveness of biofilm removal from FRCs through a novel cleaning device that uses an ultrasonically activated stream (UAS). In this device, ultrasound enhances the cleaning properties of microbubbles in a freely flowing stream of water. The UAS was applied on two types of commercial FRCs which were covered with biofilm growth following twelve days immersion in the marine environment. Biofilm removal was quantified in terms of reduction in biovolume and surface roughness, both measured using an optical profilometer, which were then compared with similar measurements after cleaning with a non-ultrasonically activated water stream. It was found that the UAS significantly improves the cleaning capabilities of a water flow, up to the point where no detectable biofilm remained on the coating surfaces. Overall biofilm surface coverage was significantly lower on the FRC coatings cleaned with the UAS system when compared to the coatings cleaned with water or not cleaned at all. When biofilm biomass removal was investigated, the UAS system resulted in significantly lower biovolume values even when compared to the water cleaning treatment with biovolume values close to zero. Remarkably, the surface roughness of the coatings after cleaning with the UAS was found to be comparable to that of the blank, non-immersed coatings, illustrating that the UAS did not damage the coatings in the process. The data supporting this study are openly available from the University of Southampton repository at http

  9. Fuzzy Clustering Using the Convex Hull as Geometrical Model

    Directory of Open Access Journals (Sweden)

    Luca Liparulo

    2015-01-01

    Full Text Available A new approach to fuzzy clustering is proposed in this paper. It aims to relax some constraints imposed by known algorithms using a generalized geometrical model for clusters that is based on the convex hull computation. A method is also proposed in order to determine suitable membership functions and hence to represent fuzzy clusters based on the adopted geometrical model. The convex hull is not only used at the end of clustering analysis for the geometric data interpretation but also used during the fuzzy data partitioning within an online sequential procedure in order to calculate the membership function. Consequently, a pure fuzzy clustering algorithm is obtained where clusters are fitted to the data distribution by means of the fuzzy membership of patterns to each cluster. The numerical results reported in the paper show the validity and the efficacy of the proposed approach with respect to other well-known clustering algorithms.

  10. Terrestrial laser scanning used to detect asymmetries in boat hulls

    Science.gov (United States)

    Roca-Pardiñas, Javier; López-Alvarez, Francisco; Ordóñez, Celestino; Menéndez, Agustín; Bernardo-Sánchez, Antonio

    2012-01-01

    We describe a methodology for identifying asymmetries in boat hull sections reconstructed from point clouds captured using a terrestrial laser scanner (TLS). A surface was first fit to the point cloud using a nonparametric regression method that permitted the construction of a continuous smooth surface. Asymmetries in cross-sections of the surface were identified using a bootstrap resampling technique that took into account uncertainty in the coordinates of the scanned points. Each reconstructed section was analyzed to check, for a given level of significance, that it was within the confidence interval for the theoretical symmetrical section. The method was applied to the study of asymmetries in a medium-sized yacht. Identified were differences of up to 5 cm between the real and theoretical sections in some parts of the hull.

  11. Wave-induced Ship Hull Vibrations in Stochastic Seaways

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Dogliani, M.

    1996-01-01

    -Gaussian in stationary stochastic seaways. The statistical properties of a response are here described by the first four statistical moments through a Hermite series approximation to the probability density function. The peak value distributions of the low and high frequency responses are treated independently, due......A theoretical Study is undertaken on the determination of wave-induced loads in flexible ship hulls. The calculations are performed within the framework of a non-linear, quadratic strip theory formulated in the frequency domain. Included are non-linear effects due to changes in added mass...... to the large separation between dominating wave frequencies and the lowest two-node frequency of the hull beam. Both extreme value predictions and fatigue damage are considered.For a fast container ship the rigid body and two-node (springing) vertical wave-induced bending moments amidship are calculated...

  12. A Mean Point Based Convex Hull Computation Algorithm

    Directory of Open Access Journals (Sweden)

    Digvijay Singh

    2016-11-01

    Full Text Available The optimal solution of a Linear Programming problem (LPP is a basic feasible solution and all basic feasible solutions are extreme or boundary points of a convex region formed by the constraint functions of the LPP. In fact, the feasible solution space is not always a convex set so the verification of extreme points for optimality is quite difficult. In order to cover the non-convex feasible points within a convex set, a convex hull is imagined so that the extreme or boundary points may be checked for evaluation of the optimum solution in the decision-making process. In this article a computer assisted convex hull computation algorithm using the Mean Point and Python code verified results of the designed algorithm are discussed.

  13. Antioxidant Properties of Water-Soluble Gum from Flaxseed Hulls.

    Science.gov (United States)

    Bouaziz, Fatma; Koubaa, Mohamed; Barba, Francisco J; Roohinejad, Shahin; Chaabouni, Semia Ellouz

    2016-08-02

    Soluble flaxseed gum (SFG) was extracted from flax (Linum usitatissimum) hulls using hot water, and its functional groups and antioxidant properties were investigated using infrared spectroscopy and different antioxidant assays (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), reducing power capacity, and β-carotene bleaching inhibition assay), respectively. The antioxidant capacity of SFG showed interesting DPPH radical-scavenging capacity (IC50 SFG = 2.5 mg·mL(-1)), strong ABTS radical scavenging activity (% inhibition ABTS = 75.6% ± 2.6% at 40 mg·mL(-1)), high reducing power capacity (RPSFG = 5 mg·mL(-1)), and potent β-carotene bleaching inhibition activity (IC50 SFG = 10 mg·mL(-1)). All of the obtained results demonstrate the promising potential use of SFG in numerous industrial applications, and a way to valorize flaxseed hulls.

  14. Development of 100W class blue direct diode laser coating system for laser metal deposition

    Science.gov (United States)

    Higashino, R.; Tsukamoto, M.; Sato, Y.; Abe, N.; Asano, K.; Funada, Y.

    2017-02-01

    Laser cladding technique is widely used for industrial application such as oil, energy industry, and aircraft and so on because it is able to repair and to form a near net shape. This process have been employed infrared lasers with wavelength of 0.8-10.6μm since output power of these lasers have over 1000W. Metal processing efficiency was, however, low in these wavelength, because the absorption was low. Thus, we developed the laser cladding system with blue direct diode laser at the wavelength of 445nm. 6 blue diode lasers was combined on the focusing spot to reach the output power of 100W by a lens, which one blue diode laser module was maximum output power of 20W. By using this laser cladding system, a pure copper film coating on a SUS304 stainless steel plate was demonstrated from a copper powder. As the result, the copper layer was formed on SUS304 stainless steel plate at the width of 322μm and thickness of 534μm was formed on the substrate.

  15. Symmetric Compound Parabolic Concentrator with Indium Tin Oxide Coated Glass as Passive Cooling System for Photovoltaic Application

    OpenAIRE

    Damasen Ikwaba Paul

    2016-01-01

    One problem with concentrating photovoltaic systems is the increase in operating photovoltaic module temperature which results in power output reduction. Indium Tin Oxide (ITO) coated glasses exhibit both high transmittance in the visible region and high reflectance in the infrared region of the solar spectrum. Such materials can be used as selective windows in photovoltaic modules operating under concentrating system enabling passive cooling. In this paper, a Heat Reflector Window (HRW) cons...

  16. LINEAR AND NONLINEAR BUCKLING ANALYSIS OF STIFFENED CYLINDRICAL SUBMARINE HULL

    OpenAIRE

    SREELATHA P.R; ALICE MATHAI

    2012-01-01

    Submarine is a watercraft capable of independent operation under water. Use of submarines includes marine science, offshore industry underwater exploration etc. The pressure hull of submarine is constructed as combination of cylinders and domes. The shell is subjected to very high hydrostatic pressure, which creates large compressive stress resultants. Due to this the structure is susceptible to buckling. The introduction of stiffeners in both directions considerably increases the buckling st...

  17. A Numerical Model for Torsion Analysis of Composite Ship Hulls

    Directory of Open Access Journals (Sweden)

    Ionel Chirica

    2012-01-01

    Full Text Available A new methodology based on a macroelement model proposed for torsional behaviour of the ship hull made of composite material is proposed in this paper. A computer program has been developed for the elastic analysis of linear torsion. The results are compared with the FEM-based licensed soft COSMOS/M results and measurements on the scale simplified model of a container ship, made of composite materials.

  18. Prediction of propeller-induced hull-pressure fluctuations

    OpenAIRE

    Van Wijngaarden, H.C.J.

    2011-01-01

    The cavitating propeller often forms the primary source of noise and vibration on board ships. The propeller induces hydroacoustic pressure fluctuations due to the passing blades and, more importantly, the dynamic activity of cavities in the propeller’s immediate vicinity. The accurate prediction of the resulting vibratory hull-excitation forces is indispensible in the ship design process, but is not always warranted. From this follows the main objective of the thesis, which is the developmen...

  19. Metalclad Airship Hull Study. Volume 1 and Volume 2

    Science.gov (United States)

    1976-12-01

    functipning .in, harmony with elastic deformations of the skiA and are h’ghly.. red •,ndant both, in loading (since they are continuoas.,qircular beams) as... perimetral stations, the apex cornice will not require reinforcement. The frame can be reduced in height all along its perimeter from its present structural...sealed off by thin flat sheet, spot welded to corrugations. The inner perimetral corridor within each main frame is gas tight and contains air under hull

  20. Lower Bound for Convex Hull Area and Universal Cover Problems

    CERN Document Server

    Khandhawit, Tirasan; Sriswasdi, Sira

    2011-01-01

    In this paper, we provide a lower bound for an area of the convex hull of points and a rectangle in a plane. We then apply this estimate to establish a lower bound for a universal cover problem. We showed that a convex universal cover for a unit length curve has area at least 0.232239. In addition, we show that a convex universal cover for a unit closed curve has area at least 0.0879873.

  1. The structure and properties of single-layer and gradient-layered coatings of the Ti–Al–Si–Cr–Mo–S–N system

    Energy Technology Data Exchange (ETDEWEB)

    Ovchinnikov, Stanislav, E-mail: ovm@spti.tsu.ru; Pinzhin, Yurii, E-mail: pinzhin@phys.tsu.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation); National Research Tomsk State University, Tomsk, 634050 (Russian Federation)

    2015-10-27

    Using the method of microprobe analysis and transmission electron microscopy, the influence of obtaining conditions upon particular elemental composition and growth structure coatings of Ti–Al–Si–Mo–S–N system was studied. The possibility of formation and characteristics of the structural and elastic-stress state single-layer coatings with nanoscale columnar or equiaxed grains and gradient-layered, combining two types of selected structure, was defined. On the basis of hardness, tribological properties and coating hardness, a conclusion was made about the relative prospects of its use as wear-resistant coatings with a nanocrystalline structure.

  2. Antifouling Coatings Influence both Abundance and Community Structure of Colonizing Biofilms: a Case Study in the Northwestern Mediterranean Sea

    OpenAIRE

    Camps, Mercedes; Barani, Aude; Gregori, Gerald; Bouchez, Agnes; Le Berre, Brigitte; Bressy , Christine; Blache, Yves

    2014-01-01

    When immersed in seawater, substrates are rapidly colonized by both micro- and macroorganisms. This process is responsible for important economic and ecological prejudices, particularly when related to ship hulls or aquaculture nets. Commercial antifouling coatings are supposed to reduce biofouling, i.e., micro- and macrofoulers. In this study, biofilms that primarily settled on seven different coatings (polyvinyl chloride [PVC], a fouling release coating [FRC], and five self-polishing copoly...

  3. Effect of graded interlayer on the mode I edge delamination by residual stresses in multilayer coating-based systems

    Science.gov (United States)

    Zhang, X. C.; Xu, B. S.; Wang, H. D.; Wu, Y. X.

    2008-01-01

    The mode I edge delamination could be initiated due to the presence of the interfacial peeling stresses near the edges of the multilayered systems due to the material mismatches between the adjacent layers. However, the exact peeling stress distributions could not be obtained by using the existing analytical and numerical models. It was proposed recently that the peeling moment resulting from the localized peeling stresses could be used to characterize mode I edge delamination. In this paper, the effect of the graded interlayer on the mode I edge delamination by thermal residual stresses in multilayer coating-based systems was investigated. Following the previous analysis approaches, the exact closed-form solutions for the peeling moments at individual interfaces and the curvatures for bilayer system, typical thermal barrier coating (TBC) system and TBC-based system with a graded interlayer inserted between the metallic layer and the ceramic layer were, respectively, derived. Case studies showed that the edge delamination by thermal stress could be impeded by properly selecting the coating materials and individual layer thicknesses. These studies may provide some important insights for developing fail-safe designing methodologies for multilayered systems.

  4. Structural and acoustic response of a finite stiffened submarine hull

    Science.gov (United States)

    Wang, Xian-zhong; Jiang, Chen-ban; Xu, Rui-yang

    2016-12-01

    After borrowing the idea of precise integration method, a precise integration transfer matrix method (PITMM) is proposed by modifying traditional transfer matrix method. The submarine hull can be modeled as joined conicalcylindrical-spherical shells. By considering the effect of the ring-stiffeners, the field transfer matrixes of shells of revolution are obtained accurately by PITMM. After assembling the field transfer matrixes into an entire matrix, the dynamic model is established to solve the dynamic responses of the joined shell. By describing the sound pressure in fluid by modified wave superposition method (MWSM) and collocating points along the meridian line of the joined shell, finally the structural and acoustic responses of a finite stiffened submarine hull can be predicted by coupled PITMM and MWSM. The effectiveness of the present method has been verified by comparing the structural and acoustic responses of the spherical shell with existing results. Furthermore, the effects of the model truncation, stiffness and thickness on the structural and acoustic responses of the submarine hull are studied.

  5. Free-surface flow around an appended hull

    Science.gov (United States)

    Lungu, A.; Pacuraru, F.

    2010-08-01

    The prediction of the total drag experienced by an advancing ship is a complicated problem which requires a thorough understanding of the hydrodynamic forces acting on the hull, the physical processes from which these forces arise as well as their mutual interaction. A general numerical method to predict the hydrodynamic performance of a twin-propeller combatant ship is presented in the paper, which describes the solution of a RANS solver coupled with a body force method as an attempt in investigating the flow features around the ship hull equipped with rotating propellers and rudders. A special focus is made on the propeller non-symmetrical inflow field, aimed at obtaining the necessary data for the propulsive performances evaluation as well as for the propeller final design. The reported work allows not only the performance evaluation for the overall performances of a hull, but also leads to the development, implementation and validation of new concepts in modeling the turbulent vortical flows, with direct connection to the ship propulsion problem.

  6. Free-surface flow around an appended hull

    Energy Technology Data Exchange (ETDEWEB)

    Lungu, A; Pacuraru, F, E-mail: adrian.lungu@ugal.r [Department of Ship Hydrodynamics, ' Dunarea de Jos' University of Galati 47 Domneasca Street, Galati 800008 (Romania)

    2010-08-15

    The prediction of the total drag experienced by an advancing ship is a complicated problem which requires a thorough understanding of the hydrodynamic forces acting on the hull, the physical processes from which these forces arise as well as their mutual interaction. A general numerical method to predict the hydrodynamic performance of a twin-propeller combatant ship is presented in the paper, which describes the solution of a RANS solver coupled with a body force method as an attempt in investigating the flow features around the ship hull equipped with rotating propellers and rudders. A special focus is made on the propeller non-symmetrical inflow field, aimed at obtaining the necessary data for the propulsive performances evaluation as well as for the propeller final design. The reported work allows not only the performance evaluation for the overall performances of a hull, but also leads to the development, implementation and validation of new concepts in modeling the turbulent vortical flows, with direct connection to the ship propulsion problem.

  7. HULL GESTURE AND RESISTANCE PREDICTION OF HIGH-SPEED VESSELS*

    Institute of Scientific and Technical Information of China (English)

    NI Chong-ben; ZHU Ren-chuan; MIAO Guo-ping; FAN Ju

    2011-01-01

    Since trim and sinkage are significant while vessels are advancing forward with high speed, the predicted vessel resistance based on restrained model theory or experiment may not be real resistance of vessels during voyage. It is necessary to take the influence of hull gesture into account for oredicting the resistance of high-speed ship. In the present work the resistance problem of high speed ship is treated with the viscous flow theory, and the dynamic mesh technique is adopted to coincide with variation of hull gesture of high speed vessel on voyage. The simulation of the models of S60 ship and a trimaran moving in towing tank with high speed are conducted by using the above theory and technique. The corresponding numerical results are in good agreement with the experimental data. It indicates that the resistance prediction for high speed vessels should take hull gesture into consideration and the dynamic mesh method proposed here is effective in calculating the resistance of high speed vessels.

  8. Antioxidant and antiproteinase effects of buckwheat hull extracts

    Directory of Open Access Journals (Sweden)

    Ernest Šturdík

    2013-03-01

    Full Text Available Buckwheat is known not only due to its appropriate nutritional composition but the content of prophylactic compounds, too. These are responsible for buckwheat beneficial impact on human health. Most of them are concentrated in outer layers of buckwheat grain. The subject of this work was to screen hulls of nine common and one tartary buckwheat cultivar for the content of flavonoids and its antioxidant and antiproteinase effects. The highest content of total flavonoids was determined for tartary buckwheat cultivar Madawaska (0.6% of hulls weight. Among common buckwheat cultivars the best values reached samples Bamby (0.23% and KASHO-2 (0.11%. Antioxidant activity as detected via binding radical ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid and monitoring reducing power was the most effective for samples with highest flavonoid content. Buckwheat hulls effectively inhibited pathophysiological proteases thrombin and urokinase, whereas only little effects were seen to trypsin and elastase. In this testing there were again the best samples with highest flavonoid content. Only tartary buckwheat Madawaska effectively inhibited elastase at tested concentrations. No significant correlation was determined between flavonoid content and measured antioxidant or protease inhibitory action. Obtained results allow us to commend tartary buckwheat cultivar Madawaska as well as common buckwheat cultivars Bamby and KASHO-2 for further experiments.doi:10.5219/272

  9. Photocatalytic and biocidal activities of novel coating systems of mesoporous and dense TiO₂-anatase containing silver nanoparticles.

    Science.gov (United States)

    Roldán, María V; de Oña, Paula; Castro, Yolanda; Durán, Alicia; Faccendini, Pablo; Lagier, Claudia; Grau, Roberto; Pellegri, Nora S

    2014-10-01

    Here we describe the development of novel nanostructured coating systems with improved photocatalytic and antibacterial activities. These systems comprise a layer of SiO2 followed by a layer of mesoporous or dense TiO2-anatase, and doping with silver nanoparticles (Ag NPs). The coatings were synthesized via a sol-gel technique by combining colloidal Ag NPs with TiO2 and SiO2 sols. The photocatalytic activity was studied through methyl orange decomposition under UV light. Results showed a great increase of photocatalytic activity by Ag NPs doping. The most active photocatalyst corresponded to the Ag-SiO2/TiO2 mesoporous system, associated with the porosity of the coatings and with the decrease of e-h recombination for the presence of Ag NPs. All the TiO2 coatings showed a strong bactericidal activity against planktonic forms of Gram-negative (enterohemorrhagic Escherichia coli) and Gram-positive (Listeria monocytogenes) pathogens, as well as a strong germicidal effect against deadly spores of human gas gangrene- and anthrax-producing bacteria (Clostridium perfringens and Bacillus anthracis, respectively). The bactericidal and sporocidal activity was improved by doping the coatings with Ag NPs, even more when nanoparticles were in the outer layer of TiO2, because they are more accessible to the environment. The mechanisms responsible for the increase of photocatalytic and bactericidal behaviors related to Ag NP doping were studied by spectroscopic ellipsometry, UV-vis spectroscopy, photoluminescence and anodic stripping voltammetry. It was found that the separation of the electron-hole pair contributed to the enhancement of photocatalysis, whereas the effect of the local electric field reinforcement was probably present. A possible involvement of a decrease of band-gap energy and dispersion by silver nanoparticles is ruled out. bactericidal efficacy was increased by Ag(+) ion release. Overall, the results included in this article show that the architecture of the

  10. Fire-retardant coatings based on organic bromine/phenoxy or brominated epoxy systems

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D.M.; Chiu, Ing L.

    1989-06-01

    Thin phenoxy and brominated epoxy/curing agent films were prepared by solvent casting on Mylar and Kapton. Thicknesses were approximated assuming volume additivity. Important parameters were uniformity of thickness, distribution of the bromine-containing fire retardant, adhesion to carrier substrate (either Mylar or Kapton), and uniformity of the coating, i.e., absence of pinholes, blush, blistering, etc. Wetting behavior was modified using fluoro, silicone or polyurea surfactants. Several solvent systems were examined and a ternary solvent system was ultimately used. Distribution of fire-retardant bromine was analyzed using electron microprobe, x-ray fluorescence and wet chemical methods. Significant discrepancies in the /mu/m-scale analyses of the microprobe measurements have not been resolved. Some of the brominated fire retardants were insoluble in the resin systems and the phase separation was immediately obvious. Similarly, some of the crystallizable epoxies could not be cast easily into homogeneous, amorphous films. Castings were made on a standard 8'' /times/ 10'' aluminum vacuum plate polished with jeweler's rouge prior to every casting. Solvent was removed in a forced air or vacuum oven. Removal and/or curing was accelerated with temperature. The fire-retardant bromine was required to be stable in alcohol/salt solutions. Final formulation used after a significant amount of testing was phenoxy resin PKHC in a ternary solvent system composed of methylethyl ketone, cellosolve acetate and toluene. Tetrabromobisphenol A was used as the flame retardant with FC-430 as surfactant. The dying schedule was 30 minutes at 150/degree/C. 4 refs., 6 figs., 3 tabs.

  11. Two-dimensional modeling of stepped planing hulls with open and pressurized air cavities

    Directory of Open Access Journals (Sweden)

    Konstantin I. Matveev

    2012-06-01

    Full Text Available A method of hydrodynamic discrete sources is applied for two-dimensional modeling of stepped planing surfaces. The water surface deformations, wetted hull lengths, and pressure distribution are calculated at given hull attitude and Froude number. Pressurized air cavities that improve hydrodynamic performance can also be modeled with the current method. Presented results include validation examples, parametric calculations of a single-step hull, effect of trim tabs, and performance of an infinite series of periodic stepped surfaces. It is shown that transverse steps can lead to higher lift-drag ratio, although at reduced lift capability, in comparison with a stepless hull. Performance of a multi-step configuration is sensitive to the wave pattern between hulls, which depends on Froude number and relative hull spacing.

  12. Anticorrosive coatings: a review

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Kiil, Søren; Dam-Johansen, Kim

    2009-01-01

    The main objective of this review is to describe some of the important topics related to the use of marine and protective coatings for anticorrosive purposes. In this context, "protective" refers to coatings for containers, offshore constructions, wind turbines, storage tanks, bridges, rail cars......, and petrochemical plants while "marine" refers to coatings for ballast tanks, cargo holds and cargo tanks, decks, and engine rooms on ships. The review aims at providing a thorough picture of state-of-the-art in anticorrosive coatings systems. International and national legislation aiming at reducing the emission...... of volatile organic compounds (VOCs) have caused significant changes in the anticorrosive coating industry. The requirement for new VOC-compliant coating technologies means that coating manufacturers can no longer rely on the extensive track record of their time-served products to convince consumers...

  13. Microwave-assisted extraction of polyphenols from Camellia oleifera fruit hull.

    Science.gov (United States)

    Zhang, Liangliang; Wang, Yongmei; Wu, Dongmei; Xu, Man; Chen, Jiahong

    2011-05-27

    The abundant fruit hulls of tea-oil tree (Camellia oleifera) are still underutilized and wastefully discaded to pollute the environment. In order to solve this problem and better utilize the fruit hulls of C. oleifera, a microwave-assisted extraction system was used to extract their polyphenols using water as the extraction solvent. A central composite design (CCD) was used to monitor the effects of three extraction processing parameters--liquid:solid ratio (mL/g), extraction time (min) and extraction temperature (°C)--on the polyphenol yield (%). The results showed that the optimal conditions were liquid:solid ratio of 15.33:1 (mL/g), extraction time of 35 min and extraction temperature of 76 °C. Validation tests indicated that under the optimized conditions the actual yield of polyphenols was 15.05 ± 0.04% with RSD = 0.21% (n = 5), which was in good agreement with the predicted yield. Phenolic compounds in the extracts were analysed by HPLC, and gallic acid was found to be the predominant constituent. The total flavonoid content in the extracts was determined and high total flavonoid content was revealed (140.06 mg/g dry material).

  14. Microwave-Assisted Extraction of Polyphenols from Camellia oleifera Fruit Hull

    Directory of Open Access Journals (Sweden)

    Jiahong Chen

    2011-05-01

    Full Text Available The abundant fruit hulls of tea-oil tree (Camellia oleifera are still underutilized and wastefully discaded to pollute the environment. In order to solve this problem and better utilize the fruit hulls of C. oleifera, a microwave-assisted extraction system was used to extract their polyphenols using water as the extraction solvent. A central composite design (CCD was used to monitor the effects of three extraction processing parameters – liquid:solid ratio (mL/g, extraction time (min and extraction temperature (°C – on the polyphenol yield (%. The results showed that the optimal conditions were liquid:solid ratio of 15.33:1 (mL/g, extraction time of 35 min and extraction temperature of 76 °C. Validation tests indicated that under the optimized conditions the actual yield of polyphenols was 15.05 ± 0.04% with RSD = 0.21% (n = 5, which was in good agreement with the predicted yield. Phenolic compounds in the extracts were analysed by HPLC, and gallic acid was found to be the predominant constituent. The total flavonoid content in the extracts was determined and high total flavonoid content was revealed (140.06 mg/g dry material.

  15. Coating and curing apparatus and methods

    Energy Technology Data Exchange (ETDEWEB)

    Brophy, Brenor L.; Gonsalves, Peter R.; Maghsoodi, Sina; Colson, Thomas E.; Yang, Yu S.; Abrams, Ze' ev R.

    2016-04-19

    Disclosed is a coating apparatus including flow coating and roll-coating that may be used for uniform sol-gel coating of substrates such as glass, solar panels, windows or part of an electronic display. Also disclosed are methods for substrate preparation, flow coating and roll coating. Lastly, systems and methods for curing sol-gel coatings deposited onto the surface of glass substrates using high temperature air-knives, infrared emitters and direct heat applicators are disclosed.

  16. Patients’ safety: is there a systemic release of gentamicin by gentamicin-coated tibia nails in clinical use?

    Science.gov (United States)

    Moghaddam, Arash; Graeser, Viola; Westhauser, Fabian; Dapunt, Ulrike; Kamradt, Till; Woerner, Stefan M; Schmidmaier, Gerhard

    2016-01-01

    Introduction Osteitis is one of the most serious complications in orthopedic surgery. Expert Tibia Nail (ETN) PROtect™ coated with a biodegradable layer of gentamicin-laden polymer was developed for prophylaxis of osteomyelitis. In systemic administration, gentamicin has only a small therapeutic index and serious side effects; it is potentially nephrotoxic as well as ototoxic. It is not yet known if relevant gentamicin concentrations are released into the systemic circulation after implantation of gentamicin-coated nails. In order to evaluate the patients’ risks profiles and increase patient safety, we measured gentamicin levels in pre- and postoperative serum samples of patients undergoing implantation of ETN PROtect. Methods Twenty-five patients who received ETN PROtect between March 2012 and August 2014 were included in this study. Collection of blood samples occurred before the operation, at weeks 1–4, 3 and 6 months, and up to 1 year after the implantation. Measurement of gentamicin levels in serum samples was performed at the central laboratory of Heidelberg University Hospital. Additionally, laboratory parameters, C-reactive protein, leukocyte number, urea and creatinine concentrations were analyzed in routine controls before and after operating and assessed for systemic side effects. Results Over the course of this prospective observational study, we were able to determine that gentamicin-coated nails do not release gentamicin into the systemic circulation above the lowest detectable level of 0.2 mg/dL. There were slight increases in the mean inflammation and renal retention markers, but no gentamicin-associated side effects could be linked to implantation. Furthermore, no allergic reactions could be detected during our study. Conclusion Our findings suggest that there is no relevant release of gentamicin into the systemic circulation causing a systemic effect, and serious side effects due to gentamicin-coated tibia nails should not be feared

  17. Design of a High Speed Planing Hull with a Cambered Step and Surface Piercing Hydrofoils

    Science.gov (United States)

    2014-06-01

    Design of a High Speed Planing Hull with a Cambered Step and Surface Piercing Hydrofoils by Leon Alexander Faison Bachelor of Science in...Speed Planing Hull with a Cambered Step and Surface Piercing Hydrofoils 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...cambered step and stern, surface piercing hydrofoils , commonly known as a Dynaplane hull. This configuration combines the drag reduction benefits of a

  18. Protective coatings of hafnium dioxide by atomic layer deposition for microelectromechanical systems applications

    Science.gov (United States)

    Berdova, Maria; Wiemer, Claudia; Lamperti, Alessio; Tallarida, Grazia; Cianci, Elena; Lamagna, Luca; Losa, Stefano; Rossini, Silvia; Somaschini, Roberto; Gioveni, Salvatore; Fanciulli, Marco; Franssila, Sami

    2016-04-01

    This work presents the investigation of HfO2 deposited by atomic layer deposition (ALD) from either HfD-CO4 or TEMAHf and ozone for microelectromechanical systems (MEMS) applications, in particular, for environmental protection of aluminum micromirrors. This work shows that HfO2 films successfully protect aluminum in moist environment and at the same time retain good reflectance properties of underlying material. In our experimental work, the chemical composition, crystal structure, electronic density and roughness of HfO2 films remained the same after one week of humidity treatment (relative humidity of 85%, 85 °C). The reflectance properties underwent only minor changes. The observed shift in reflectance was only from 80-90% to 76-85% in 400-800 nm spectral range when coated with ALD HfO2 films grown with Hf(NMeEt)4 and no shift (remained in the range of 68-83%) for films grown from (CpMe)2Hf(OMe)Me.

  19. Strategies for interfacing inorganic nanocrystals with biological systems based on polymer-coating.

    Science.gov (United States)

    Palui, Goutam; Aldeek, Fadi; Wang, Wentao; Mattoussi, Hedi

    2015-01-01

    Interfacing inorganic nanoparticles and biological systems with the aim of developing novel imaging and sensing platforms has generated great interest and much activity. However, the effectiveness of this approach hinges on the ability of the surface ligands to promote water-dispersion of the nanoparticles with long term colloidal stability in buffer media. These surface ligands protect the nanostructures from the harsh biological environment, while allowing coupling to target molecules, which can be biological in nature (e.g., proteins and peptides) or exhibit specific photo-physical characteristics (e.g., a dye or a redox-active molecule). Amphiphilic block polymers have provided researchers with versatile molecular platforms with tunable size, composition and chemical properties. Hence, several groups have developed a wide range of polymers as ligands or micelle capsules to promote the transfer of a variety of inorganic nanomaterials to buffer media (including magnetic nanoparticles and semiconductor nanocrystals) and render them biocompatible. In this review, we first summarize the established synthetic routes to grow high quality nanocrystals of semiconductors, metals and metal oxides. We then provide a critical evaluation of the recent developments in the design, optimization and use of various amphiphilic copolymers to surface functionalize the above nanocrystals, along with the strategies used to conjugate them to target biomolecules. We finally conclude by providing a summary of the most promising applications of these polymer-coated inorganic platforms in sensor design, and imaging of cells and tissues.

  20. Simulation of residual stresses and their effects on thermal barrier coating systems using finite element method

    Science.gov (United States)

    Zhu, JianGuo; Chen, Wei; Xie, HuiMin

    2015-03-01

    Thermal barrier coating (TBC) systems are widely used in industrial gas-turbine engines. However, premature failures have impaired the use of TBCs and cut down their lifetime, which requires a better understanding of their failure mechanisms. In the present study, experimental studies of isothermal cycling are firstly carried out with the observation and estimation of microstructures. According to the experimental results, a finite element model is established for the analysis of stress perpendicular to the TBC/BC interface. Detailed residual stress distributions in TBC are obtained to reflect the influence of mechanical properties, oxidation, and interfacial roughness. The calculated results show that the maximum tensile stress concentration appears at the peak of TBC and continues to increase with thermal cycles. Because of the microstructural characteristics of plasma-sprayed TBCs, cracks initialize in tensile stress concentration (TSC) regions at the peaks of TBC and propagate along the TBC/BC interface resulting in the spallation of TBC. Also, the inclusion of creep is crucial to failure prediction and is more important than the inclusion of sintering in the simulation.

  1. Polymer Derived Rare Earth Silicate Nanocomposite Protective Coatings for Nuclear Thermal Propulsion Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this Phase I SBIR program is to develop polymer derived rare earth silicate nanocomposite environmental barrier coatings (EBC) for providing...

  2. Symbiotic Behavior during Co-culturing of Clostridium thermocellum NKP-2 and Thermoanaerobacterium thermosaccharolyticum NOI-1 on Corn Hull

    Directory of Open Access Journals (Sweden)

    Suphavadee Chimtong

    2014-03-01

    Full Text Available The symbiosis of co-culturing between Clostridium thermocellum NKP-2 and Thermoanaerobacterium thermosaccharolyticum NOI-1 is described. An efficient biomass-degrading enriched culture was isolated from soil that contained two different bacterial strains showing homology to C. thermocellum and T. thermosaccharolyticum. The enzymatic system produced from the isolated strains when cultivated individually on corn hulls demonstrated different cellulolytic and xylanolytic enzyme activities. Strain NKP-2 produced cellulose- and xylan-main chain cleaving enzymes such as carboxymethylcellulase (CMCase, avicelase, and xylanase as major enzymes, whereas strain NOI-1 produced primarily short- and side-chain cleaving enzymes such as cellobiohydrolase, β-glucosidase, β-xylosidase, acetyl esterase, and especially α-L-arabinofuranosidase. Enhancement of corn hull utilization, cell growth, and fermentation products (ethanol, butanol, acetic acid, butyric acid, H2, and CO2 was greatly increased during co-culturing compared with individual cultivation of both strains. The symbiotic behavior between both strains was one of mutualism, in which the synergistic degradation of corn hulls by co-action of cellulolytic and xylanolytic enzymes promoted hydrolysis of biomass for growth and fermented products.

  3. Effects of coatings on storability of carrot under evaporative coolant system.

    OpenAIRE

    Adetunji Charles Oluwaseun; Arowora Kayode; Fawole Oluyemisi Bolajoko; Adetunji Juliana Bunmi

    2013-01-01

    Four different coatings were developed from the mucilage of Cactus and their effects were investigated on the quality and storability of carrot fruits. The four experimental coatings were: Pure mucilage extracts (ME), Mucilage extract mixed with 5ml glycerol (MEG), Mucilage extract mixed 5ml soy oil ( MESO), Mucilage extract mixed with 5ml olive oil(MEOO) the addition of oil served as plasticizer. The following parameters were measured: weight loss, ascorbic acid content, pH, firmness and mic...

  4. Effect of acrylic polymers on physical parameters of spheronized pellets using an aqueous coating system

    Directory of Open Access Journals (Sweden)

    Akhter Afsana

    2009-01-01

    Full Text Available The aim of this study was to develop ambroxol hydrochloride sustained release pellets by an extrusion-spheronization technique and subsequent coating with acrylic polymers. Acrylic polymers like Eudragit RL 30 D, Eudragit RS 30 D and Eudragit NE 30 D were used as release retarding coating polymers. The release retarding capability of these polymers was also investigated. In each case, 10% polymer on dry basis was loaded. The flow property, surface roughness as well as the drug release behavior of the pellets was found to be the subject of types of polymers. About 35% drug was released at the first hour in 0.1N HCl media (pH 1.2 from Eudragit RL 30 D-coated pellets but from Eudragit RS 30 D and Eudragit NE 30 D-coated pellets, only 13.75 and 2.43% drug was released, respectively. In buffer media (pH 6.8, about 54% drug was released at the first hour from Eudragit RL 30 D-coated pellets but only 64% drug was released at 10 h. From Eudragit RL 30 D- and Eudragit NE 30 D-coated pellets only 7.28 and 1.14% drug was released at 1 h, respectively, but about 5.14 and 5.86 h was required for 50% drug release from these two polymers and about 80% drug was released at 10 h. The functional groups present in the polymeric films played a significant role on in vitro release kinetics of the drug from the coated pellets. Different kinetic models like zero order, first order and Higuchi were used for fitting the drug release pattern. The Higuchi model was the best fitted for ambroxol release from the coated pellets. The drug release mechanism was derived with Korsmeyer equation.

  5. Systems design of COATLI: an all-sky robotic optical imager with 0.3 arcsec image quality

    Science.gov (United States)

    Cuevas, Salvador; Langarica, Rosalia; Watson, Alan M.; Fuentes-Fernández, Jorge; Ángeles, Fernando; Farah, Alejandro S.; Figueroa, Liliana; Becerra-Godínez, Rosa L.; Chapa, Oscar; Román-Zúñiga, Carlos G.; Quiróz, Fernando; Tejada, Carlos; Álvarez-Núñez, Luis C.; Ruz, Jaime; Tinoco, Silvio J.

    2016-08-01

    COATLI is a new instrument and telescope that will provide 0.3 arcsec FWHM images from 550 to 920 nm over a large fraction of the sky. It consists of a robotic 50-cm telescope with a diffraction-limited imager. The imager has a steering mirror for fast guiding, a blue channel using an EMCCD from 400 to 550 nm to measure image motion, a red channel using a standard CCD from 550 to 920 nm, and an active optics system based on a deformable mirror to compensate static aberrations in the red channel. Since the telescope is small, fast guiding will provide diffraction-limited image quality in the red channel over a large fraction of the sky, even in relatively poor seeing. The COATLI telescope will be installed at the Observatorio Astronómico Nacional in Sierra San Pedro Mártir, Baja California, México, in 2016 and will initially operate with a simple interim imager. The definitive COATLI instrument will be installed in 2017. In this work we present the general optomechanical and control electronics design of COATLI.

  6. Surface studies on superhydrophobic and oleophobic polydimethylsiloxane-silica nanocomposite coating system

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Bharathibai J., E-mail: bharathi@nal.res.in [Surface Engineering Division, CSIR-National Aerospace Laboratories, Bangalore 560017 (India); Dinesh Kumar, V.; Anandan, C. [Surface Engineering Division, CSIR-National Aerospace Laboratories, Bangalore 560017 (India)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Superhydrophobic coatings were rendered oleophobic by applying a topcoat of FAS. Black-Right-Pointing-Pointer The coatings exhibited stable oleophobic property with oil CA of 79 Degree-Sign . Black-Right-Pointing-Pointer Fluoroalkyl groups have more affinity towards silica nanoparticles than for PDMS. Black-Right-Pointing-Pointer Very small amount of fluorine was required to render oil repellency to the coating. - Abstract: Superhydrophobic and oleophobic polydimethylsiloxane (PDMS)-silica nanocomposite double layer coating was fabricated by applying a thin layer of low surface energy fluoroalkyl silane (FAS) as topcoat. The coatings exhibited WCA of 158-160 Degree-Sign and stable oleophobic property with oil CA of 79 Degree-Sign . The surface morphology was characterized by field emission scanning electron microscopy (FESEM) and surface chemical composition was determined by energy dispersive X-ray spectrometery (EDX) and X-ray photoelectron spectroscopy (XPS). FESEM images of the coatings showed micro-nano binary structure. The improved oleophobicity was attributed to the combined effect of low surface energy of FAS and roughness created by the random distribution of silica aggregates. This is a facile, cost-effective method to obtain superhydrophobic and oleophobic surfaces on larger area of various substrates.

  7. Ship Hull Form Optimization by Evolutionary Algorithm in Order to Diminish the Drag

    Institute of Scientific and Technical Information of China (English)

    Hassan Zakerdoost; Hassan Ghassemi; Mahmoud Ghiasi

    2013-01-01

    This study presents a numerical method for optimizing hull form in calm water with respect to total drag which contains a viscous drag and a wave drag.The ITTC 1957 model-ship correlation line was used to predict frictional drag and the corrected linearized thin-ship theory was employed to estimate the wave drag.The evolution strategy (ES) which is a member of the evolutionary algorithms (EAs) family obtains an optimum hull form by considering some design constraints.Standard Wigley hull is considered as an initial hull in optimization procedures for two test cases and new hull forms were achieved at Froude numbers 0.24,0.316 and 0.408.In one case the ES technique was ran for the initial hull form,where the main dimensions were fixed and the only variables were the hull offsets.In the other case in addition to hull offsets,the main dimensions were considered as variables that are optimized simultaneously.The numerical results of optimization procedure demonstrate that the optimized hull forms yield a reduction in total drag.

  8. Grounding-Induced Sectional Forces and Residual Strength of Grounded Ship Hulls

    DEFF Research Database (Denmark)

    Paik, Jeom Kee; Pedersen, Preben Terndrup

    1996-01-01

    The aim of the present study is to determine the sectional forces induced by ship grounding and also to assess the residual strength of groundedship hulls. An analytical approach is used to estimate the grounding-induced sectional forces of ships. The extent and location of structural damage due...... to grounding is defined based on the ABS Safe Hull guide. The residual strength of damaged hulls is calculated by using a simple analytical formula. The method is applied to residual strength assessment of a damaged double hull tanker of 38,400 dwt due to grounding....

  9. Protective coatings of hafnium dioxide by atomic layer deposition for microelectromechanical systems applications

    Energy Technology Data Exchange (ETDEWEB)

    Berdova, Maria, E-mail: maria.berdova@aalto.fi [Aalto University, Department of Materials Science and Engineering, 02150, Espoo (Finland); Wiemer, Claudia; Lamperti, Alessio; Tallarida, Grazia; Cianci, Elena [Laboratorio MDM, IMM CNR, Via C. Olivetti 2, 20864, Agrate Brianza, MB (Italy); Lamagna, Luca; Losa, Stefano; Rossini, Silvia; Somaschini, Roberto; Gioveni, Salvatore [STMicroelectronics, Via C. Olivetti 2, 20864, Agrate Brianza, MB (Italy); Fanciulli, Marco [Laboratorio MDM, IMM CNR, Via C. Olivetti 2, 20864, Agrate Brianza, MB (Italy); Università degli studi di Milano Bicocca, Dipartimento di Scienza dei Materiali, 20126, Milano (Italy); Franssila, Sami, E-mail: sami.franssila@aalto.fi [Aalto University, Department of Materials Science and Engineering, 02150, Espoo (Finland)

    2016-04-15

    Graphical abstract: - Highlights: • Atomic layer deposition of HfO{sub 2} from (CpMe){sub 2}Hf(OMe)Me or Hf(NMeEt){sub 4} and ozone for potential applications in microelectromechanical systems. • ALD HfO{sub 2} protects aluminum substrates from degradation in moist environment and at the same time retains good reflectance properties of the underlying material. • The resistance of hafnium dioxide to moist environment is independent of chosen precursors. - Abstract: This work presents the investigation of HfO{sub 2} deposited by atomic layer deposition (ALD) from either HfD-CO4 or TEMAHf and ozone for microelectromechanical systems (MEMS) applications, in particular, for environmental protection of aluminum micromirrors. This work shows that HfO{sub 2} films successfully protect aluminum in moist environment and at the same time retain good reflectance properties of underlying material. In our experimental work, the chemical composition, crystal structure, electronic density and roughness of HfO{sub 2} films remained the same after one week of humidity treatment (relative humidity of 85%, 85 °C). The reflectance properties underwent only minor changes. The observed shift in reflectance was only from 80–90% to 76–85% in 400–800 nm spectral range when coated with ALD HfO{sub 2} films grown with Hf(NMeEt){sub 4} and no shift (remained in the range of 68–83%) for films grown from (CpMe){sub 2}Hf(OMe)Me.

  10. Yttria-stabilized zirkonia / gadolinium zirconate double-layer plasma-sprayed thermal barrier coating systems (TBCs)

    Energy Technology Data Exchange (ETDEWEB)

    Bakan, Emine

    2015-07-01

    Thermal barrier coating (TBC) research and development is driven by the desirability of further increasing the maximum inlet temperature in a gas turbine engine. A number of new top coat ceramic materials have been proposed during the last decades due to limited temperature capability (1200 C) of the state-of-the-art yttria-stabilized zirconia (7 wt. % Y{sub 2}O{sub 3}-ZrO{sub 2}, YSZ) at long term operation. Zirconate pyrochlores of the large lanthanides((Gd → La){sub 2}Zr{sub 2}O{sub 7}) have been particularly attractive due to their higher temperature phase stability than that of the YSZ. Nonetheless, the issues related with the implementation of pyrochlores such as low fracture toughness and formation of deleterious interphases with thermally grown oxide (TGO, Al{sub 2}O{sub 3}) were reported. The implication was the requirement of an interlayer between the pyrochlores and TGO, which introduced double-layer systems to the TBC literature. Furthermore, processability issues of pyrochlores associated with the different evaporation rates of lanthanide oxides and zirconia resulting in unfavorable composition variations in the coatings were addressed in different studies. After all, although the material properties are available, there is a paucity of data in the literature concerning the properties of the coatings made of pyrochlores. From the processability point of view the most reported pyrochlore is La{sub 2}Zr{sub 2}O{sub 7}. Hence, the goal of this research was to investigate plasma-sprayed Gd{sub 2}Zr{sub 2}O{sub 7} (GZO) coatings and YSZ/GZO double-layer TBC systems. Three main topics were examined based on processing, performance and properties: (i) the plasma spray processing of the GZO and its impact on the microstructural and compositional properties of the GZO coatings; (ii) the cycling lifetime of the YSZ/GZO double-layer systems under thermal gradient at a surface temperature of 1400 C; (iii) the properties of the GZO and YSZ coatings such as

  11. Evaluation of the biological activity of sunflower hull extracts

    Directory of Open Access Journals (Sweden)

    Taha, F. S.

    2012-06-01

    Full Text Available This work was planned with the aim of adding value to sunflower seed hulls, a waste product of the oil industry by preparing a sunflower hull phenolic extract rich in chlorogenic acid (CGA. In order to fulfill this goal, the optimization for the extraction of a phenolic extract from the hulls was investigated. The parameters studied were: type of solvent, solvent to water ratio and hull to solvent ratio. In addition, the solvent mixtures were also studied. The resulting phenolic extracts were evaluated for their biological activities. This included phenolic content determination, evaluation of the antioxidant and antimicrobial activities. Chlorogenic acid was determined in two chosen hull extracts using the UV spectrophotometric method and HPLC analysis. The anticarcinogenic activity of the two chosen extracts was tested on seven different cell line carcinomas. The results revealed that all the phenolic extracts of sunflower hull studied contain between 190-312.5 mg phenolics/ 100 g hulls. The highest phenolic extraction was achieved with 80% methanol (1:30, hull to solvent, w/v ratio and methanol to ethanol to water (7:7:6 v/v/v mixture with values of 312.5 and 306.5 mg phenolics/100 g hulls, respectively. The free radical scavenging activity and antioxidant activity of all the samples ranged from 33.6-72.6%. The highest antioxidant activity and free radical scavenging activity were achieved by the same extracts that possessed the highest phenolic content, namely methanol to ethanol to water extract and 80% methanol with values 71.8 and 72.6%, 68.2 and 70.9% respectively, compared to 77.9 and 76.9% respectively for TBHQ. All the phenolic extracts possessed antimicrobial activity but to different levels against different pathogenic bacteria. The two chosen extracts also possessed anticarcinogenic activity, which differed among varying cell line carcinomas. The HPLC analysis indicated that chlorogenic acid was the main phenolic acid in the

  12. Advanced Multifunctional Coating

    Science.gov (United States)

    2011-08-17

    and UV durability of then current chrome free TT-P-2756 SPTC • Leverage APC technology into SPTC • Coating uses same fluoropolyurethane technology...as APC currently used on C-17 • Leverage recent advances in chrome free corrosion inhibitor technology • State of the art chrome free corrosion...coat exposed metal Aluminum Base Metal Original Finish System Aged APC Topcoat Conversion Coat Chromic Acid Anodize Aluminum Cladding Original Primer

  13. The Causes of Boat Hull Blisters

    Science.gov (United States)

    1987-05-01

    a standard, specification, or regulation. This report, or portions thereof may not be used for advertising or sales promotion purposes. Citation of...D. S. Edgell , and A. G. Hankin. ’Blister performance of GRP systems in Aqueous environments." 36th Annual Conference, SPI Reinforced Plastics

  14. A Combined Brazing and Aluminizing Process for Repairing Turbine Blades by Thermal Spraying Using the Coating System NiCrSi/NiCoCrAlY/Al

    Science.gov (United States)

    Nicolaus, M.; Möhwald, K.; Maier, H. J.

    2017-08-01

    The repair and maintenance of components in the aerospace industry play an increasingly important role due to rising manufacturing costs. Besides welding, vacuum brazing is a well-established repair process for turbine blades made of nickel-based alloys. After the coating of the worn turbine blade has been removed, the manual application of the nickel-based filler metal follows. Subsequently, the hot gas corrosion-protective coating is applied by thermal spraying. The brazed turbine blade is aluminized to increase the hot gas corrosion resistance. The thermal spray technology is used to develop a two-stage hybrid technology that allows shortening the process chain for repair brazing turbine blades and is described in the present paper. In the first step, the coating is applied on the base material. Specifically, the coating system employed here is a layer system consisting of nickel filler metal, NiCoCrAlY and aluminum. The second step represents the combination of brazing and aluminizing of the coating system which is subjected to a heat treatment. The microstructure, which results from the combined brazing and aluminizing process, is characterized and the relevant diffusion processes in the coating system are illustrated. The properties of the coating and the ramifications with respect to actual applications will be discussed.

  15. Coating system of hydrogen storage alloy powder slurry; Suiso kyuzo gokin funmatsu surari no tofu sochi

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, J.

    1995-03-31

    As the hydrogen storage alloy powder slurry has a high density and a high viscosity, it is necessary to apply a considerably high tension to the current collector sheet when the current collector sheet is continuously coated with the hydrogen storage alloy powder slurry. This invention provides a method of continuously coating the hydrogen storage alloy powder slurry on the running current collector sheet. In order to keep the viscosity of alloy powder slurry constant and to reduce the tension to be applied to the sheet during coating, a stirring jig is installed facing to the front surface and back surface of the current collector sheet and rotating in the sheet running direction and in the opposite direction. In this way, the thixotropic structure of the hydrogen storage alloy powder slurry is constantly broken, so that a gradual increase in viscosity does not take place. Resultingly, the homogeneous hydrogen storage alloy electrode can be continuously produced. 6 figs.

  16. "Thunderstruck": Plasma-Polymer-Coated Porous Silicon Microparticles As a Controlled Drug Delivery System.

    Science.gov (United States)

    McInnes, Steven J P; Michl, Thomas D; Delalat, Bahman; Al-Bataineh, Sameer A; Coad, Bryan R; Vasilev, Krasimir; Griesser, Hans J; Voelcker, Nicolas H

    2016-02-01

    Controlling the release kinetics from a drug carrier is crucial to maintain a drug's therapeutic window. We report the use of biodegradable porous silicon microparticles (pSi MPs) loaded with the anticancer drug camphothecin, followed by a plasma polymer overcoating using a loudspeaker plasma reactor. Homogenous "Teflon-like" coatings were achieved by tumbling the particles by playing AC/DC's song "Thunderstruck". The overcoating resulted in a markedly slower release of the cytotoxic drug, and this effect correlated positively with the plasma polymer coating times, ranging from 2-fold up to more than 100-fold. Ultimately, upon characterizing and verifying pSi MP production, loading, and coating with analytical methods such as time-of-flight secondary ion mass spectrometry, scanning electron microscopy, thermal gravimetry, water contact angle measurements, and fluorescence microscopy, human neuroblastoma cells were challenged with pSi MPs in an in vitro assay, revealing a significant time delay in cell death onset.

  17. Surface studies on superhydrophobic and oleophobic polydimethylsiloxane-silica nanocomposite coating system

    Science.gov (United States)

    Basu, Bharathibai J.; Dinesh Kumar, V.; Anandan, C.

    2012-11-01

    Superhydrophobic and oleophobic polydimethylsiloxane (PDMS)-silica nanocomposite double layer coating was fabricated by applying a thin layer of low surface energy fluoroalkyl silane (FAS) as topcoat. The coatings exhibited WCA of 158-160° and stable oleophobic property with oil CA of 79°. The surface morphology was characterized by field emission scanning electron microscopy (FESEM) and surface chemical composition was determined by energy dispersive X-ray spectrometery (EDX) and X-ray photoelectron spectroscopy (XPS). FESEM images of the coatings showed micro-nano binary structure. The improved oleophobicity was attributed to the combined effect of low surface energy of FAS and roughness created by the random distribution of silica aggregates. This is a facile, cost-effective method to obtain superhydrophobic and oleophobic surfaces on larger area of various substrates.

  18. Water permeability of pigmented waterborne coatings

    NARCIS (Netherlands)

    Donkers, P.A.J.; Huinink, H.P.; Erich, S.J.F.; Reuvers, N.J.W.; Adan, O.C.G.

    2013-01-01

    Coatings are used in a variety of applications. Last decades more and more coating systems are transforming from solvent to waterborne coating systems. In this study the influence of pigments on the water permeability of a waterborne coating system is studied, with special interest in the possible i

  19. Surfactant-coated Candida rugosa Lipase as Catalyst for Hydrolysis of Olive Oil in Solvent-Free Two-Phase System

    Institute of Scientific and Technical Information of China (English)

    宋宝东; 丁辉; 吴金川; HayashiY.; TalukderMMR; 王世昌

    2003-01-01

    The surfactant-coated Candida rugosa lipase was used as catalyst for hydrolysis of olive oil in two-phase system consisting of olive oil and phosphate buffer without organic solvent. For both the coated and native lipases,the optimal buffer/oil volume ratio of 1.0, aqueous pH 6.8 and reaction temperature 30℃ were determined. The maximum activity of the coated lipase was ca 1.3 times than that of the native lipase. The half-life of the coated lipase in olive oil and the native lipase in phosphate buffer was ca 9 h and 12 h, and the final residual activity was 27% and 20% of their initial values, respectively. The final substrate conversion by the coated lipase was ca 20% higher than that of the native lipase.

  20. A new carbon structure in annealed film coatings of the carbon-lead system

    Science.gov (United States)

    Volodin, V. N.; Tuleushev, Yu. Zh.; Zhakanbaev, E. A.; Tsai, K. V.; Rofman, O. V.

    2017-01-01

    Carbon-lead solid solutions coexisting with amorphous carbon have been obtained for the first time in a film coating deposited by ion-plasma sputtering. During subsequent vacuum annealing of carbon-lead films containing more than 68.5 at % Pb, this element almost completely evaporates to leave an amorphous carbon coating on a substrate. During annealing at 1100°C, this amorphous carbon crystallizes into a new hexagonal lattice with unit cell parameters a = 0.7603 nm and c = 0.8168 nm. Characteristic X-ray diffraction data for the identification of this phase are determined.

  1. Thermal/residual stress in an electron beam physical vapor deposited thermal barrier coating system

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, J.; Jordan, E.H.; Barber, B.; Gell, M. [Univ. of Connecticut, Storrs, CT (United States)

    1998-10-09

    Elastic-plastic finite element models are used to define the thermal/residual stress state responsible for the observed failure behavior of an electron beam physical vapor deposited yttria stabilized zirconia thermal barrier coating on a Pt-Al bond coat. The failures were observed to start at grain boundary ridges, some of which evolved into oxide filled cavities. Finite element models are made of the actual interface geometries through the use of metallographic sectioning and imaging processing. There is a one to one correspondence of calculated tension in the oxide layer and the observed localized damage. Purely elastic analysis failed to show some important tensile regions associated with the observed failure.

  2. Experimental Program for the Determination of Hull Structural Damping Coefficients.

    Science.gov (United States)

    1981-09-01

    approaches are appar- ent. One concept is to have each individual excitation device self contained, and to control the phasing and amplitude of the motions...n ma. cllt r ibu-t si,,nificantly to hull damping hut avai.1lt iu, lo 1 , , ht if tt I - scle and from model tests, toil to adequo tI e ly :anf Wtf... controlled excitations. It is generally understood that the total damping consists of at least three basic components, i.e. hydrodynamic, cargo and structural

  3. Tank Tests of Model 36 Flying Boat Hull

    Science.gov (United States)

    Allison, John

    1938-01-01

    N.A.C.A. Model 36, a hull form with parallel middle body for half the length of the forebody and designed particularly for use with stub wings, was tested according to the general fixed-trim method over the range of practical loads, trims, and speeds. It was also tested free to trim with the center of gravity at two different positions. The results are given in the form of nondimensional coefficients. The resistance at the hump was exceptionally low but, at high planing speeds, afterbody interference made the performance only mediocre.

  4. Numerical Study of the Hull-Propeller-Rudder Interaction

    Science.gov (United States)

    Lungu, Adrian; Pacuraru, Florin

    2009-09-01

    The paper describes the solution of a RANS solver coupled with a body force method as an attempt in investigating the flow features around a maneuvering containership equipped with a rotating propeller and rudder. A special focus is made on the propeller non-symmetrical inflow field, aimed at obtaining the necessary data for the propulsive performances evaluation as well as for the propeller final design. The reported work allows not only the performance evaluation for the overall performances of a hull, but also leads to the development, implementation and validation of new concepts in modeling the turbulent vortical flows, with direct connection to the ship propulsion problem.

  5. On the Influence of Hull Girder Flexibility on the Wave

    DEFF Research Database (Denmark)

    Seng, Sopheak; Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2012-01-01

    Numerical predictions and model test results of the wave induced bending moments in a 9,400 TEU post-Panamax container vessel are presented for two regular wave scenarios. Different numerical procedures have been applied: a linear and non-linear time-domain strip theory and a direct calculation (...... (CFD) solving the Navier-Stokes equations with the free surface captured by a volume-of-fluid (VOF) method. In all procedures the flexibility of the hull girder is modelled as a non-uniform Timoshenko beam. It is observed that the non-linear models agree well with the model tests...

  6. Hulled and hull-less barley cultivars with the genetic trait for low-phytic acid increased the apparent digestibility of phosphorus and calcium in diets for young swine

    Science.gov (United States)

    A 35-d experiment was conducted using 63 crossbred pigs (35 barrows and 28 gilts) with an average initial BW of 7.0 kg and age of 28 d to evaluate the efficacy of the low-phytic acid (LPA) genetic trait in hulled and hull-less barley cultivars. The hulled cultivars were Harrington normal barley (NB)...

  7. 33 CFR 80.135 - Hull, MA to Race Point, MA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Hull, MA to Race Point, MA. 80.135 Section 80.135 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Atlantic Coast § 80.135 Hull, MA to Race Point, MA....

  8. Gamma radiation effects on phenolics, antioxidants activity and in vitro digestion of pistachio (Pistachia vera) hull

    Energy Technology Data Exchange (ETDEWEB)

    Behgar, M., E-mail: mbehgar@nrcam.org [Agricultural, Medical and Industrial Research School, P.O. Box 31485498, Karaj (Iran, Islamic Republic of); Ghasemi, S.; Naserian, A. [Faculty of Agriculture, Excellence Center in Animal Science, Ferdowsi University of Mashhad, P.O. Box 917751163, Mashhad (Iran, Islamic Republic of); Borzoie, A.; Fatollahi, H. [Agricultural, Medical and Industrial Research School, P.O. Box 31485498, Karaj (Iran, Islamic Republic of)

    2011-09-15

    The effect of gamma radiation (10, 20, 30, 40, 50 and 60 kGy) on tannin, total phenolics, antioxidants activity and in vitro digestion of pistachio hulls has been investigated in this study. The possibility of using the radial diffusion method based on software measurement of the rings area has also been investigated in this study. The software based method in radial diffusion method showed a higher r{sup 2} (0.995) value when compared to the traditional method. Irradiation reduced the tannin content (P<0.01) and activity of antioxidants (P<0.05) of pistachio hull extracts but increased the total phenolic content (P<0.05). There was no effect of gamma irradiation on the in vitro digestion of the pistachio hull. Irradiation decreased the digestion rate of the pistachio hull at the dose of 40 kGy when compared to the control. This study showed that gamma irradiation decreased tannin and antioxidants activity of pistachio hull. - Highlights: > we investigate the effects of gamma irradiation on pistachio hull. > We examine changes in phenolics, antioxidant and digestion of pistachio hull. > Computerized radial diffusion method gives precise regression for standard curve. > Gamma irradiation will decrease tannin and antioxidants of pistachio hull extracts.

  9. On Convex Hull of Orthogonal Scalar Spectral Functions of a Carleman Operator

    Directory of Open Access Journals (Sweden)

    S. M. Bahri

    2008-11-01

    Full Text Available In this paper we describe the closed convex hull of orthogonal resolvents of an abstract symmetric operator of defect indices (1; 1, then we study the convex hull of orthogonal spectral functions of a Carleman operator in the Hilbert space L^2(X;mu.

  10. Edith de Nancrede at Hull-House: Theatre Programs for Youth.

    Science.gov (United States)

    Hecht, Stuart J.

    1991-01-01

    Describes the work of Edith de Nancrede in developing theater programs for youth at Chicago's Hull-House during the early part of the twentieth century. Describes how her intense dedication to theater and education contributed to the success of Hull-House and to the achievements of its leader, Jane Addams. (PRA)

  11. Distributed Topological Convex Hull Estimation of Event Region in Wireless Sensor Networks without Location Information

    NARCIS (Netherlands)

    Guo, Peng; Cao, Jiannong; Zhang, Kui

    2015-01-01

    In critical event (e.g., fire or gas) monitoring applications of wireless sensor networks (WSNs), convex hull of the event region is an efficient tool in handling the usual tasks like event report, routes reconstruction and human motion planning. Existing works on estimating convex hull of event

  12. Edith de Nancrede at Hull-House: Theatre Programs for Youth.

    Science.gov (United States)

    Hecht, Stuart J.

    1991-01-01

    Describes the work of Edith de Nancrede in developing theater programs for youth at Chicago's Hull-House during the early part of the twentieth century. Describes how her intense dedication to theater and education contributed to the success of Hull-House and to the achievements of its leader, Jane Addams. (PRA)

  13. Effect of rice hull mulch on nutrient concentration of fertilized irrigation water

    Science.gov (United States)

    Parboiled rice hulls are an effective mulch for controlling weeds in nursery containers. A layer of rice hulls between 1.25 and 2.5 cm deep has been shown to provide effective control of liverwort (Marchantia polymorpha), bittercress (Cardamine flexuosa), and creeping woodsorrel (Oxalis corniculata...

  14. Distributed topological convex hull estimation of event region in wireless sensor networks without location information

    NARCIS (Netherlands)

    Guo, Peng; Cao, Jiannong; Zhang, Kui

    2015-01-01

    In critical event (e.g., fire or gas) monitoring applications of wireless sensor networks (WSNs), convex hull of the event region is an efficient tool in handling the usual tasks like event report, routes reconstruction and human motion planning. Existing works on estimating convex hull of event reg

  15. Rice hull smoke extract inactivates Salmonella Typhimurium in laboratory media and protects infected mice against mortality

    Science.gov (United States)

    A recently discovered and characterized rice hull liquid smoke extract was tested for bactericidal activity against Salmonella Typhimurium using the disc-agar method. The Minimum Inhibitory Concentration (MIC) value of rice hull smoke extract was found to be 0.822% (v/v). The in vivo antibacterial a...

  16. Electrodepositing behaviors and properties of nano Fe-Ni-Cr/SiC composite coatings from trivalent chromium baths containing compound carboxylate-urea system.

    Science.gov (United States)

    He, Xinkuai; Hou, Bailong; Cai, Youxing; Li, Chen; Jiang, Yumei; Wu, Luye

    2013-06-01

    The nano Fe-Ni-Cr/SiC composite coatings were prepared using pulse electrodeposition method from trivalent chromium baths containing compound carboxylate-urea system and nano SiC in ultrasonic field. The effects of the carboxylate-urea system on the nano Fe-Ni-Cr/SiC composite coatings have been investigated. These results indicated that the SiC and Cr contents and the thickness of the Fe-Ni-Cr/SiC composite coatings could be obviously improved by the compound carboxylate-urea system. The steady-state polarization curves showed that the hydrogen evolution reaction (HER) could be significantly inhibited by the compound carboxylate-urea system, which was benefit to increase the SiC and Cr contents and the thickness of the composite coatings. The cyclic voltammetry (CV) curves showed that the cathodic polarization of the matrix metal ions could be increased in the bath containing the compound carboxylate-urea system. Thus, a compact Fe-Ni-Cr/SiC composite coating could be obtained using this technique. The surface morphology of the Fe-Ni-Cr/SiC composite coatings checked with the scanning electron micrographs (SEM) showed that the surface smoothness could be also improved and the microcracks and pinholes could be decreased due to the presence of the compound carboxylate-urea system. The phase composition of the as-posited coating was measured by the X-ray diffraction (XRD). XRD data showed that the as-posited coating was Fe-Ni-Cr/SiC composite coating. The chemical composition of the coating was investigated by energy dispersive spectrum (EDS) analysis. The result showed the functional Fe-Ni-Cr/SiC composite coatings with 4.1 wt.% SiC and 25.1 wt.% Cr, and 23.9 microm thickness were obtained in this study, which had best corrosion resistance according to the results of the typical potentiodynamic polarization curves of the Fe-Ni-Cr/SiC composite coatings.

  17. Development of Cubic Bezier Curve and Curve-Plane Intersection Method for Parametric Submarine Hull Form Design to Optimize Hull Resistance Using CFD

    Institute of Scientific and Technical Information of China (English)

    Deddy Chrismianto; Ahmad Fauzan Zakki; Berlian Arswendo; Dong Joon Kim

    2015-01-01

    Optimization analysis and computational fluid dynamics (CFDs) have been applied simultaneously, in which a parametric model plays an important role in finding the optimal solution. However, it is difficult to create a parametric model for a complex shape with irregular curves, such as a submarine hull form. In this study, the cubic Bezier curve and curve-plane intersection method are used to generate a solid model of a parametric submarine hull form taking three input parameters into account: nose radius, tail radius, and length-height hull ratio (L/H). Application program interface (API) scripting is also used to write code in the ANSYS DesignModeler. The results show that the submarine shape can be generated with some variation of the input parameters. An example is given that shows how the proposed method can be applied successfully to a hull resistance optimization case. The parametric design of the middle submarine type was chosen to be modified. First, the original submarine model was analyzed, in advance, using CFD. Then, using the response surface graph, some candidate optimal designs with a minimum hull resistance coefficient were obtained. Further, the optimization method in goal-driven optimization (GDO) was implemented to find the submarine hull form with the minimum hull resistance coefficient (Ct). The minimum Ct was obtained. The calculated difference in Ct values between the initial submarine and the optimum submarine is around 0.26%, with the Ct of the initial submarine and the optimum submarine being 0.001 508 26 and 0.001 504 29, respectively. The results show that the optimum submarine hull form shows a higher nose radius (rn) and higher L/H than those of the initial submarine shape, while the radius of the tail (rt) is smaller than that of the initial shape.

  18. Development of cubic Bezier curve and curve-plane intersection method for parametric submarine hull form design to optimize hull resistance using CFD

    Science.gov (United States)

    Chrismianto, Deddy; Zakki, Ahmad Fauzan; Arswendo, Berlian; Kim, Dong Joon

    2015-12-01

    Optimization analysis and computational fluid dynamics (CFDs) have been applied simultaneously, in which a parametric model plays an important role in finding the optimal solution. However, it is difficult to create a parametric model for a complex shape with irregular curves, such as a submarine hull form. In this study, the cubic Bezier curve and curve-plane intersection method are used to generate a solid model of a parametric submarine hull form taking three input parameters into account: nose radius, tail radius, and length-height hull ratio ( L/ H). Application program interface (API) scripting is also used to write code in the ANSYS design modeler. The results show that the submarine shape can be generated with some variation of the input parameters. An example is given that shows how the proposed method can be applied successfully to a hull resistance optimization case. The parametric design of the middle submarine type was chosen to be modified. First, the original submarine model was analyzed, in advance, using CFD. Then, using the response surface graph, some candidate optimal designs with a minimum hull resistance coefficient were obtained. Further, the optimization method in goal-driven optimization (GDO) was implemented to find the submarine hull form with the minimum hull resistance coefficient ( C t ). The minimum C t was obtained. The calculated difference in C t values between the initial submarine and the optimum submarine is around 0.26%, with the C t of the initial submarine and the optimum submarine being 0.001 508 26 and 0.001 504 29, respectively. The results show that the optimum submarine hull form shows a higher nose radius ( r n ) and higher L/ H than those of the initial submarine shape, while the radius of the tail ( r t ) is smaller than that of the initial shape.

  19. Load rate dependence of the mechanical properties of thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Zotov, Nikolay; Eggeler, Gunther [Institut fuer Werkstoffe, Ruhr Universitaet Bochum, 44780 Bochum (Germany); Bartsch, Marion [Institut fuer Werkstoff-Forschung, DLR Koeln, 51147 Koeln (Germany)

    2009-07-01

    Thermal barrier coatings (TBC), composed of yttrium-stabilized zirconia (YSZ) ceramic top coat (TC) and intermetallic NiCoCrAlY bond coat (BC) are commonly used as protective coatings of Ni-based high temperature gas engine components. Nanoindentation techniques are increasingly applied for determining the TBC mechanical properties on a nanometre scale. However, little is known about the load-rate dependence of the mechanical properties, which is important for better understanding of cyclic thermal fatigue experiments. Nanoindentations with different load rates omega were performed on polished cross-sections of TBC, deposited by EB-PVD on IN625 substrates (S), using a XP Nanoindenter (MTS) equipped with Berkovich diamond tip. The Young's modulus (E) of the TC is independent of omega, while E for the BC and the S decreases with omega. The hardness (H) of the TC and the BC increases, while H for the S decreases with omega. From the dependence of H on omega, creep power-law exponents c = 0.24(11) and c = 0.023(6) for the TC and the BC were determined. For all TBC components, a decrease with omega of the power-law exponents n and m, describing the loading and unloading nanoindentation curves, is observed.

  20. Advanced fiber information systems seed coat neps baseline response from diverse mediums

    Science.gov (United States)

    An extensive literature search has revealed that no papers have been published regarding selectivity calculation of the AFIS seed coat neps (SCN) determination over interfering material in cotton. A prerequisite to selectivity measurements is to identify suitable fiber medium(s) that give baseline ...

  1. Gamma radiation effects on phenolics, antioxidants activity and in vitro digestion of pistachio ( Pistachia vera) hull

    Science.gov (United States)

    Behgar, M.; Ghasemi, S.; Naserian, A.; Borzoie, A.; Fatollahi, H.

    2011-09-01

    The effect of gamma radiation (10, 20, 30, 40, 50 and 60 kGy) on tannin, total phenolics, antioxidants activity and in vitro digestion of pistachio hulls has been investigated in this study. The possibility of using the radial diffusion method based on software measurement of the rings area has also been investigated in this study. The software based method in radial diffusion method showed a higher r2 (0.995) value when compared to the traditional method. Irradiation reduced the tannin content ( Ppistachio hull extracts but increased the total phenolic content ( Ppistachio hull. Irradiation decreased the digestion rate of the pistachio hull at the dose of 40 kGy when compared to the control. This study showed that gamma irradiation decreased tannin and antioxidants activity of pistachio hull.

  2. PENGKLASIFIKASIAN DEBITUR DENGAN MENGGUNAKAN ALGORITMA GRAHAM SCAN DALAM PENGAPLIKASIAN CONVEX HULL

    Directory of Open Access Journals (Sweden)

    AGUS EKA ARIESTA

    2014-01-01

    Full Text Available Computational geometry is the mathematical science of computation by using the algorithm analysis to solve the problems of geometry. The problems of computational include polygon triangulations, convex hulls, Voronoi diagrams, and motion planning. Convex hull is the set of points that form a convex polygon that covers the entire set of points. The algorithms for determining the convex hull, among others, Graham Scan, Jarvis March, and Divide and Conquer. In the two-dimensional case, Graham Scan algorithm is highly efficient in the use of time complexity. This article discusses the quest convex hull of the data bank debtors, some of the data used to look at the classification accuracy of the convex hull formed. The coordinates of all the data found by using principal component analysis.After the data are analyzed, we get the accuracy of classification by 74%.

  3. Removal and isolation of germ-rich fractions from hull-less barley using a fitzpatrick comminuting mill

    Science.gov (United States)

    A process was developed to produce a germ-enriched fraction from hull-less barley using a Fitzpatrick Comminuting Mill followed by sieving. Hulled and hull-less barleys contain 1.5-2.5% oil and, like wheat kernels which contain wheat germ oil, much of the oil in barley kernels is in the germ fracti...

  4. 7 CFR 319.55a - Administrative instructions relating to entry of rice straw and rice hulls into Guam.

    Science.gov (United States)

    2010-01-01

    ... straw and rice hulls into Guam. 319.55a Section 319.55a Agriculture Regulations of the Department of... QUARANTINE NOTICES Rice Quarantine § 319.55a Administrative instructions relating to entry of rice straw and rice hulls into Guam. Rice straw and rice hulls may be imported into Guam without further permit,...

  5. Evaluation of Underwater Adhesives and Friction Coatings for In Situ Attachment of Fiber Optic Sensor System for Subsea Applications

    Science.gov (United States)

    Tang, Henry H.; Le, Suy Q.; Orndoff, Evelyne S.; Smith, Frederick D.; Tapia, Alma S.; Brower, David V.

    2012-01-01

    Integrity and performance monitoring of subsea pipelines and structures provides critical information for managing offshore oil and gas production operation and preventing environmentally damaging and costly catastrophic failure. Currently pipeline monitoring devices require ground assembly and installation prior to the underwater deployment of the pipeline. A monitoring device that could be installed in situ on the operating underwater structures could enhance the productivity and improve the safety of current offshore operation. Through a Space Act Agreement (SAA) between the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) and Astro Technology, Inc. (ATI), JSC provides technical expertise and testing facilities to support the development of fiber optic sensor technologies by ATI. This paper details the first collaboration effort between NASA JSC and ATI in evaluating underwater applicable adhesives and friction coatings for attaching fiber optic sensor system to subsea pipeline. A market survey was conducted to examine different commercial ]off ]the ]shelf (COTS) underwater adhesive systems and to select adhesive candidates for testing and evaluation. Four COTS epoxy based underwater adhesives were selected and evaluated. The adhesives were applied and cured in simulated seawater conditions and then evaluated for application characteristics and adhesive strength. The adhesive that demonstrated the best underwater application characteristics and highest adhesive strength were identified for further evaluation in developing an attachment system that could be deployed in the harsh subsea environment. Various friction coatings were also tested in this study to measure their shear strengths for a mechanical clamping design concept for attaching fiber optic sensor system. A COTS carbide alloy coating was found to increase the shear strength of metal to metal clamping interface by up to 46 percent. This study provides valuable data for

  6. Analysis of organic grain coatings in primitive interplanetary dust particles: Implications for the origin of Solar System organic matter

    Science.gov (United States)

    Flynn, George

    Analysis of organic grain coatings in primitive interplanetary dust particles: Implications for the origin of Solar System organic matter Chondritic, porous interplanetary dust particles (CP IDPs), the most primitive samples of extraterrestrial material available for laboratory analysis [1], are unequilibrated aggregates of mostly submicron, anhydrous grains of a diverse mineralogy. They contain organic matter not produced by parent body aqueous processing [2], some carrying H and N isotopic anomalies consistent with molecular cloud or outer Solar System material [3]. Scanning Transmission X-Ray Microscope (STXM) imaging at the C K-edge shows the individual grains in 10 micron aggregate CP IDPs are coated by a layer of carbonaceous material 100 nm thick. This structure implies a three-step formation sequence. First, individual grains condensed from the cooling nebular gas. Then complex, refractory organic molecules covered the surfaces of the grains either by deposition, formation in-situ, or a combination of both processes. Finally, the grains collided and stuck together forming the first dust-size material in the Solar System. Ultramicrotome sections, 70 to 100 nm thick were cut from several CP IDPs, embedded in elemental S to avoid exposure to C-based embedding media. X-ray Absorption Near Edge Structure (XANES) spectra were derived from image stacks obtained using a STXM. "Cluster analysis" was used to compare the C-XANES spectra from each of the pixels in an image stack and identify pixels exhibiting similar spectra. When applied to a CP IDP, cluster analysis identifies most carbonaceous grain coatings in a particle as having similar C-XANES spectra. Two processes are commonly suggested in the literature for production of organic grain coatings. The similarity in thickness and C-XANES spectra of the coatings on different minerals in the same IDP indicates the first, mineral specific catalysis, was not the process that produced these organic rims. Our results

  7. Copper Based Antifouling Paints for Prevention of Marine Growth on ship Hulls

    Directory of Open Access Journals (Sweden)

    Y.P.S. Nirvan

    1982-01-01

    Full Text Available "The mode of action and requirements of ingredients of copper based antifouling paints used in the country for the prevention of fouling, on ship-hulls have been described. The studies on performance of antifouling paints based on cuprous oxide-chlorinated rubber-rosin system have also been reported. Antifouling life improves with increase in concentration of cuprous oxide, 43 per cent by volume being the optimum toxic content. A minimum rosin to resin ratio of 3:1 is required to permit adequate release of copper for prolonged periods. Hydrolysable plasticizer namely tricresyl phosphate has been found to be superior to chlorinated paraffin wax for the design of antifouling compositions. The antifouling paint based on chlorinated rubber resin is expected to give a life of 15-18 months in service."

  8. CYTOTOXIC AND ANTIOXIDANT ACTIVITY OF BUCKWHEAT HULL EXTRACTS

    Directory of Open Access Journals (Sweden)

    Martina Danihelová

    2013-02-01

    Full Text Available Buckwheat contains many prophylactic compounds that are concentrated mainly in outer layers of buckwheat grain. The aim of this study was to prepare buckwheat hull extracts. Ten buckwheat cultivars were screened for their antioxidant and anticancer properties. Total polyphenol content was determined using Folin-Ciocalteau's reagent. Antioxidant activity was established by the method of binding free radical DPPH. Cytotoxic properties were measured on human cervical cancer cells HeLa using mitochondrial cytotoxic test (MTT. Total polyphenol content ranged from 166.67 to 635.31 mg GAE/100 g DW. The highest content displayed tartary buckwheat cultivar Madawaska (0.64% of hulls weight. Among common buckwheat the richest in polyphenols were cultivars Bamby and KASHO-2. The best free radical binding antioxidant activity was found for cultivars with highest polyphenol content. This relationship was not observed for cytotoxic action on human cervical cancer cells. The best growth inhibitory activity on HeLa cancer cells displayed common buckwheat cultivars Bamby and KASHO-2 (up to 50%, extract concentration 100 µg/ml. This was not found for tartary buckwheat cultivar Madawaska.

  9. Remote identification of the vibration amplitude of ship hull

    Directory of Open Access Journals (Sweden)

    A. N. Pinchuk

    2014-01-01

    Full Text Available The aim is to develop the methodological support to determine vibration amplitude of the ship hull remotely using a coherent radar centimeter range based on the variation of the Doppler signal spectrum reflected from a vibrating surface.The paper presents a synthesized mathematical model of the radio signal reflected from the vibrating surface. It is the signal of coherent radar of continuous radiation with a known carrier frequency and the amplitude of the radiated signal. In the synthesis it was believed that the displacement in the radial direction with respect to the vibrating surface radar was sinusoidal.The dependences of the vibration amplitude on the value of the normalized Doppler radio signal spectrum at the second harmonic frequency are obtained. Cycle results of field experiments to study the variability of the sea surface, determining the level of its roughness, allows us to establish that the energy of surface waves of gravitational-capillary range has a high correlation with the wind speed. It is proved that the ratio of the spectral density levels at vibration frequency and its multiple frequencies is specified by the index of phase modulation linearly related to the amplitude of vibration of the ship hull.The results are significant for radar (radar detection of water targets using the coherent radar of centimeter range, ensuring the correct records of noise generated by the scattering of radio waves from the water surface.

  10. Faba bean hulls as a potential source of pectin.

    Science.gov (United States)

    Korish, Mohamed

    2015-09-01

    This study aimed for the first time to assess the potential use of faba bean hulls as a source of pectin. The study involved extracting pectin under various conditions of pH, temperature and extraction time and determining how these conditions affected pectin yield and its characteristics. The maximum yield of extracted pectin did not coincide with the highest degree of esterification since the maximum yield (15.75 %) was recorded at pH 1.5 and at a temperature of 85 °C for an 80-min extraction period and solid to liquid (1: 25) ratio, while the highest degree of esterification (54.62 %) occurred at pH 2.5 and at temperature of 90 °C for a 60-min extraction period. The composition of the pectin varied according to the extraction conditions: the neutral sugars galactose, arabinose and rhamnose increased under milder extraction conditions while glucose, mannose and xylose sugars predominated under harsher extraction conditions. The results indicated that faba bean hulls contains adequate amount of pectin, suitable for commercial utilization.

  11. Dilute Acid Hydrolysis of Cowpea Hulls: A Kinetic Study

    Directory of Open Access Journals (Sweden)

    Chioma M. Onyelucheya

    2016-08-01

    Full Text Available In this study, dilute acid hydrolysis of cowpea hulls was carried out in two stages under the following conditions: pre-hydrolysis (4%v/v H2SO4, 121˚C, 30 minutes and hydrolysis ( at 10% and 15% v/v H2SO4,varied at different temperatures 150 oC, 160 oC, 170 oC and 180 oC for 2.5 hrs.. The substrate was characterized using both Fourier transform infrared spectroscopy and proximate analysis. The percentage lignocellulosic composition of the substrate was obtained for cellulose, hemicellulose and lignin as 34%, 14% and 4.7% respectively. Maximum glucose concentration of 8.09g was obtained using 10%v/v acid concentration at 170˚C after a reaction time of 90min. Saeman’s model gave a good fit for the experimental data. Activation energy for glucose formation using 10%v/v and 15%v/v H2SO4 was obtained as 38.28KJ and 82.204KJ respectively. From the results obtained it can be concluded that cowpea hulls can be converted to a useful product.

  12. In vivo siRNA delivery system for targeting to the liver by poly-l-glutamic acid-coated lipoplex

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Hattori

    2014-01-01

    Full Text Available In this study, we developed anionic polymer-coated liposome/siRNA complexes (lipoplexes with chondroitin sulfate C (CS, poly-l-glutamic acid (PGA and poly-aspartic acid (PAA for siRNA delivery by intravenous injection, and evaluated the biodistribution and gene silencing effect in mice. The sizes of CS-, PGA- and PAA-coated lipoplexes were about 200 nm and their ζ-potentials were negative. CS-, PGA- and PAA-coated lipoplexes did not induce agglutination after mixing with erythrocytes. In terms of biodistribution, siRNAs after intravenous administration of cationic lipoplexes were largely observed in the lungs, but those of CS-, PGA- and PAA-coated lipoplexes were in both the liver and the kidneys, indicating that siRNA might be partially released from the anionic polymer-coated lipoplexes in the blood circulation and accumulate in the kidney, although the lipoplexes can prevent the agglutination with blood components. To increase the association between siRNA and cationic liposome, we used cholesterol-modified siRNA (siRNA-Chol for preparation of the lipoplexes. When CS-, PGA- and PAA-coated lipoplexes of siRNA-Chol were injected into mice, siRNA-Chol was mainly observed in the liver, not in the kidneys. In terms of the suppression of gene expression in vivo, apolipoprotein B (ApoB mRNA in the liver was significantly reduced 48 h after single intravenous injection of PGA-coated lipoplex of ApoB siRNA-Chol (2.5 mg siRNA/kg, but not cationic, CS- and PAA-coated lipoplexes. In terms of toxicity after intravenous injection, CS-, PGA- and PAA-coated lipoplexes did not increase GOT and GPT concentrations in blood. From these findings, PGA coatings for cationic lipoplex of siRNA-Chol might produce a systemic vector of siRNA to the liver.

  13. Patients’ safety: is there a systemic release of gentamicin by gentamicin-coated tibia nails in clinical use?

    Directory of Open Access Journals (Sweden)

    Moghaddam A

    2016-09-01

    Full Text Available Arash Moghaddam,1 Viola Graeser,1 Fabian Westhauser,1 Ulrike Dapunt,1 Till Kamradt,1 Stefan M Woerner,2 Gerhard Schmidmaier1 1HTRG – Heidelberg Traume Research Group Center for Orthopedics, Trauma and Spinal Cord Injury, University Hospital Heidelberg, Heidelberg, Germany; 2Department of Internal Medicine and Clinical Chemistry, University Hospital Heidelberg, Heidelberg, Germany Introduction: Osteitis is one of the most serious complications in orthopedic surgery. Expert Tibia Nail (ETN PROtect™ coated with a biodegradable layer of gentamicin-laden polymer was developed for prophylaxis of osteomyelitis. In systemic administration, gentamicin has only a small therapeutic index and serious side effects; it is potentially nephrotoxic as well as ototoxic. It is not yet known if relevant gentamicin concentrations are released into the systemic circulation after implantation of gentamicin-coated nails. In order to evaluate the patients’ risks profiles and increase patient safety, we measured gentamicin levels in pre- and postoperative serum samples of patients undergoing implantation of ETN PROtect.Methods: Twenty-five patients who received ETN PROtect between March 2012 and August 2014 were included in this study. Collection of blood samples occurred before the operation, at weeks 1–4, 3 and 6 months, and up to 1 year after the implantation. Measurement of gentamicin levels in serum samples was performed at the central laboratory of Heidelberg University Hospital. Additionally, laboratory parameters, C-reactive protein, leukocyte number, urea and creatinine concentrations were analyzed in routine controls before and after operating and assessed for systemic side effects.Results: Over the course of this prospective observational study, we were able to determine that gentamicin-coated nails do not release gentamicin into the systemic circulation above the lowest detectable level of 0.2 mg/dL. There were slight increases in the mean

  14. Fabrication and Characterization of a Porous Silicon Drug Delivery System with an Initiated Chemical Vapor Deposition Temperature-Responsive Coating.

    Science.gov (United States)

    McInnes, Steven J P; Szili, Endre J; Al-Bataineh, Sameer A; Vasani, Roshan B; Xu, Jingjing; Alf, Mahriah E; Gleason, Karen K; Short, Robert D; Voelcker, Nicolas H

    2016-01-12

    This paper reports on the fabrication of a pSi-based drug delivery system, functionalized with an initiated chemical vapor deposition (iCVD) polymer film, for the sustainable and temperature-dependent delivery of drugs. The devices were prepared by loading biodegradable porous silicon (pSi) with a fluorescent anticancer drug camptothecin (CPT) and coating the surface with temperature-responsive poly(N-isopropylacrylamide-co-diethylene glycol divinyl ether) (pNIPAM-co-DEGDVE) or non-stimulus-responsive poly(aminostyrene) (pAS) via iCVD. CPT released from the uncoated oxidized pSi control with a burst release fashion (∼21 nmol/(cm(2) h)), and this was almost identical at temperatures both above (37 °C) and below (25 °C) the lower critical solution temperature (LCST) of the switchable polymer used, pNIPAM-co-DEGDVE (28.5 °C). In comparison, the burst release rate from the pSi-pNIPAM-co-DEGDVE sample was substantially slower at 6.12 and 9.19 nmol/(cm(2) h) at 25 and 37 °C, respectively. The final amount of CPT released over 16 h was 10% higher at 37 °C compared to 25 °C for pSi coated with pNIPAM-co-DEGDVE (46.29% vs 35.67%), indicating that this material can be used to deliver drugs on-demand at elevated temperatures. pSi coated with pAS also displayed sustainable drug delivery profiles, but these were independent of the release temperature. These data show that sustainable and temperature-responsive delivery systems can be produced by functionalization of pSi with iCVD polymer films. Benefits of the iCVD approach include the application of the iCVD coating after drug loading without causing degradation of the drug commonly caused by exposure to factors such as solvents or high temperatures. Importantly, the iCVD process is applicable to a wide array of surfaces as the process is independent of the surface chemistry and pore size of the nanoporous matrix being coated.

  15. In-line Ultrasonic Array System for Monitoring Dynamic of Coating Forming by Cold Spray Process

    Science.gov (United States)

    Lubrick, M.; Titov, S.; Leshchynsky, V.; Maev, R. Gr.

    This study attempts to test the viability of studying the cold spray process using acoustic methods, specifically testing during the actual spray process itself. Multiple composites studied by flat and multi channel transducers as well as actual online measurements are presented. It is shown that the final thickness as well as the dynamics of buildup can be evaluated (including plotting rates of buildup). Cross sections of the coating thickness are also easy to obtain and show true profiles of the coating. The data can also be used to generate real estimates for nozzle speed and spray diameter. Finally comparisons of real thickness and acoustically estimated thickness show a close linear relationship with the y intercept seeming to depend on the composition. The data clearly shows that online acoustic measurement is a viable method for estimating thickness buildup.

  16. Calculation of ice clearing resistance using normal vector of hull form and direct calculation of buoyancy force under the hull

    Directory of Open Access Journals (Sweden)

    Kyung-Duk Park

    2015-07-01

    Full Text Available The ice-resistance estimation technique for icebreaking ships had been studied intensively over recent years to meet the needs of designing Arctic vessels. Before testing in the ice model basin, the estimation of a ship’s ice resistance with high reliability is very important to decide the delivered power necessary for level ice operation. The main idea of previous studies came from several empirical formulas, such as Poznyak and Ionov (1981, Enkvist (1972 and Shimansky (1938 methods, in which ice resistance components such as icebreaking, buoyancy and clearing resistances were represented by the integral equations along the Design Load Water Line (DLWL. The current study proposes a few modified methods not only considering the DLWL shape, but also the hull shape under the DLWL. In the proposed methodology, the DLWL shape for icebreaking resistance and the hull shape under the DLWL for buoyancy and clearing resistances can be directly considered in the calculation. Especially, when calculating clearing resistance, the flow pattern of ice particles under the DLWL of ship is assumed to be in accordance with the ice flow observed during ice model testing. This paper also deals with application examples for a few ship designs and its ice model testing programs at the AARC ice model basin. From the comparison of results of the model test and the estimation, the reliability of this estimation technique has been discussed.

  17. Design and Application of Novel Dispersants for Coatings and Other System

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    1 Results Dispersants are defined as liquids or gases that can be added to a mixture to promote dispersion or to maintain dispersed particles in suspension. A good dispersant not only helps to provide good dispersion, but also good performance, stability and rheological properties. Therefore, dispersants are widely used in many applications such as coating, ink, electronic materials, plastics, and so on[1]. There are different ways to categorize the many dispersants available on the market. From a molec...

  18. Reducing Friction and Wear of Tribological Systems through Hybrid Tribofilm Consisting of Coating and Lubricants

    OpenAIRE

    Shuichiro Yazawa; Ichiro Minami; Braham Prakash

    2014-01-01

    The role of surface protective additives becomes vital when operating conditions become severe and moving components operate in a boundary lubrication regime. After protecting film is slowly removed by rubbing, it can regenerate through the tribochemical reaction of the additives at the contact. However, there are limitations about the regeneration of the protecting film when additives are totally consumed. On the other hand, there are a lot of hard coatings to protect the steel surface from ...

  19. Decreased material-activation of the complement system using low-energy plasma polymerized poly(vinyl pyrrolidone) coatings

    DEFF Research Database (Denmark)

    Andersen, T.E.; Kolmos, H.J.; Palarasah, Yaseelan

    2011-01-01

    surface. The ppVP surface is furthermore characterized physically and chemically using scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR), which indicates preservation of chemical functionality by the applied plasma process. Overall, the pp......In the current study we investigate the activation of blood complement on medical device silicone rubber and present a plasma polymerized vinyl pyrrolidone (ppVP) coating which strongly decreases surface-activation of the blood complement system. We show that uncoated silicone and polystyrene...

  20. 涂装工程建设的新模式——COS体系%COS system: a new mode of coating engineering construction

    Institute of Scientific and Technical Information of China (English)

    方震

    2012-01-01

    The COS system, a new mode of coating engineering construction characterized by integrating coating, operation and service into one, is an embodiment of integration of coatings and painting, which makes the coating production factories turn a concept of only selling coating materials into providing good films for clients. In this paper, the advantages of COS system were discussed. Some cases where the coating production factories and painting equipment factories successfully applied COS system to operation were shared.%COS体系是一种集涂装、经营和服务于一体的涂装工程建设新模式,它把涂料生产厂家只卖涂料的观念转化成向客户提供优质涂膜的理念,是涂料涂装一体化的具体体现.讨论了COS体系的优点,并分享了涂料生产厂家和涂装设备厂成功应用COS体系经营的案例.

  1. Review of Hull Structural Monitoring Systems for Navy Ships

    Science.gov (United States)

    2013-05-01

    correctly identify stresses in areas where stress concentrations occur. Examples of some of the different SBSGs used in HSMS listed in Table 1...those that may induce a vibratory response in the ship structure. These loads become significant if the frequency of the load is close to the natural... Miner linear damage hypothesis is used together with S-N (Stress Range – No of Cycles) curves for welded structures to establish the fatigue life for

  2. Hybrid Wireless Hull Monitoring System for Naval Combat Vessels

    Science.gov (United States)

    2010-03-01

    sensor node (or the entire node) into sleep mode. The sensor is designed to run on 6 AA size nickel -metal hydride (NiMH) rechargeable batteries...Farrar, C.R. and Prime, M.R. (1998), "A Summary Review of Vibration-Based Damage Identification Methods", Shock and Vibration Digest , 30(2), 91-105...Structure Committee, U.S. Coast Guard, Washington, D.C., USA. Harvey, A.F. (1963), Microwave engineering, Academic Press, London and New York

  3. Refined universal laws for hull volumes and perimeters in large planar maps

    Science.gov (United States)

    Guitter, Emmanuel

    2017-07-01

    We consider ensembles of planar maps with two marked vertices at distance k from each other, and look at the closed line separating these vertices and lying at distance d from the first one (d  faces within the hull is called the hull volume, and the length of the separating line the hull perimeter. We study the statistics of the hull volume and perimeter for arbitrary d and k in the limit of infinitely large planar quadrangulations, triangulations and Eulerian triangulations. We consider more precisely situations where both d and k become large with the ratio d/k remaining finite. For infinitely large maps, two regimes may be encountered: either the hull has a finite volume and its complementary is infinitely large, or the hull itself has an infinite volume and its complementary is of finite size. We compute the probability for the map to be in either regime as a function of d/k as well as a number of universal statistical laws for the hull perimeter and volume when maps are conditioned to be in one regime or the other.

  4. A new algorithm for computing the convex hull of a planar point set

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    When the edges of a convex polygon are traversed along one direction, the interior of the convex polygon is always on the same side of the edges. Based on this characteristic of convex polygons, a new algorithm for computing the convex hull of a simple polygon is proposed in this paper, which is then extended to a new algorithm for computing the convex hull of a planar point set. First, the extreme points of the planar point set are found, and the subsets of point candidate for vertex of the convex hull between extreme points are obtained. Then, the ordered convex hull point sequences between extreme points are constructed separately and concatenated by removing redundant extreme points to get the convex hull. The time complexity of the new planar convex hull algorithm is O(nlogh), which is equal to the time complexity of the best output-sensitive planar convex hull algorithms.Compared with the algorithm having the same complexity, the new algorithm is much faster.

  5. Hydrodynamic Characteristics of a Low-drag, Planing-tail Flying-boat Hull

    Science.gov (United States)

    Suydam, Henry B

    1948-01-01

    The hydrodynamic characteristics of a flying-boat incorporating a low-drag, planing-tail hull were determined from model tests made in Langley tank number 2 and compared with tests of the same flying boat incorporating a conventional-type hull. The planing-tail model, with which stable take-offs were possible for a large range of elevator positions at all center-of-gravity locations tested, had more take-off stability than the conventional model. No upper-limit porpoising was encountered by the planing-tail model. The maximum changes in rise during landings were lower for the planing-tail model than for the conventional model at most contact trims, an indication of improved landing stability for the planing-tail model. The hydrodynamic resistance of the planing-tail hull was lower than the conventional hull at all speeds, and the load-resistance ratio was higher for the planing-tail hull, being especially high at the hump. The static trim of the planing-tail hull was much higher than the conventional hull, but the variation of trim with speed during take-off was smaller.

  6. Benzoylsalicylic acid isolated from seed coats of Givotia rottleriformis induces systemic acquired resistance in tobacco and Arabidopsis.

    Science.gov (United States)

    Kamatham, Samuel; Neela, Kishore Babu; Pasupulati, Anil Kumar; Pallu, Reddanna; Singh, Surya Satyanarayana; Gudipalli, Padmaja

    2016-06-01

    Systemic acquired resistance (SAR), a whole plant defense response to a broad spectrum of pathogens, is characterized by a coordinated expression of a large number of defense genes. Plants synthesize a variety of secondary metabolites to protect themselves from the invading microbial pathogens. Several studies have shown that salicylic acid (SA) is a key endogenous component of local and systemic disease resistance in plants. Although SA is a critical signal for SAR, accumulation of endogenous SA levels alone is insufficient to establish SAR. Here, we have identified a new acyl derivative of SA, the benzoylsalicylic acid (BzSA) also known as 2-(benzoyloxy) benzoic acid from the seed coats of Givotia rottleriformis and investigated its role in inducing SAR in tobacco and Arabidopsis. Interestingly, exogenous BzSA treatment induced the expression of NPR1 (Non-expressor of pathogenesis-related gene-1) and pathogenesis related (PR) genes. BzSA enhanced the expression of hypersensitivity related (HSR), mitogen activated protein kinase (MAPK) and WRKY genes in tobacco. Moreover, Arabidopsis NahG plants that were treated with BzSA showed enhanced resistance to tobacco mosaic virus (TMV) as evidenced by reduced leaf necrosis and TMV-coat protein levels in systemic leaves. We, therefore, conclude that BzSA, hitherto unknown natural plant product, is a new SAR inducer in plants.

  7. Electrode–electrolyte interface stability in solid state electrolyte systems: influence of coating thickness under varying residual stresses

    Directory of Open Access Journals (Sweden)

    Claas Hüter

    2017-08-01

    Full Text Available We introduce a model of electrode–electrolyte interfacial growth which focuses on theeffect of thin coating layers on the interfacial stability in prestressed systems. We take into accounttransport resulting from deposition from the electrolyte, from capillarity driven surface diffusion, andfrom changes of the chemical potential due to the elastic energy associated with the interface profile.As model system, we use metallic lithium as electrode, LLZO as electrolyte and Al2O3 as a thin filminterlayer, which is a highly relevant interfacial system in state of the art all-solid-electrolyte batteries.We consider the stability of the electrode-coating-electrolyte interface depending on the thickness ofthe thin film interlayer and the magnitude of the elastic prestresses. Our central approach is a linearstability analysis based on the mass conservation at the planar interface, employing approximationswhich are appropriate for solid state electrolytes (SSEs like LLZ, a thin Li metal electrode and a thincoating layer with a thickness in the range of nanometres.

  8. THE OPTIMIZATION OF THE HULL FORM WITH THE MINIMUM WAVE MAKING RESISTANCE BASED ON RANKINE SOURCE METHOD

    Institute of Scientific and Technical Information of China (English)

    ZHANG Bao-ji; MA Kun; JI Zhuo-shang

    2009-01-01

    The hull form optimization concerns one of the most important applications of wave making resistance theories. In order to obtain a hull form with the minimum wave making resistance, an optimization design method based on the CFD is proposed, which combines the Rankine source method with the nonlinear programming (NLP). The bow-body shape is optimized with the minimum wave making resistance as the objective function. A hull form modification function is introduced to represent an improved hull surface, which can be used to generate a new smooth hull surface by multiplying it by the offset data of the original hull surface. The parameters of the hull form modification function are taken as the design variables. Other constraint conditions can also be considered, for example, in optimizing the lines of the bow, appropriate displacements can be taken as the basic constraints. S60 hull form is selected as the original hull. Three improved hulls are obtained by optimal design. Rankine source method proves to be an effective method in ship form optimization based on analysis of the resistance performance and lines of the improved hull.

  9. Environmental Effects from In-Water Hull Cleaning of Ablative Copper Antifouling Coatings

    Science.gov (United States)

    1994-07-01

    spermatozoa . Biol. Bull., 147, 236. Zeitoun, N.A., E.F. Mandelli, W.1. Mclnhenny, and R.O. Reid. 1969. Disposal of the effluents from desalination plants...S.H. Lieberman, and C. Clavell. 1978. Measurement of Cu and Zn in San Diego Bay by automated anodic stripping voltametry. Environ. Sci. Technol., 12

  10. Fuel efficiency and fouling control coatings in maritime transport

    DEFF Research Database (Denmark)

    Lindholdt, Asger

    First, this thesis concerns the drag performance of fouling control coatings (FCCs) used to protect hulls on ships against biofouling and, therefore, minimize any drag therefrom. A systematic overview of the literature and description of the experimental methods used to quantify the drag of FCCs...... currently used consists of measuring drag when coatings are newly applied and after static exposure. It was found that the main limitation of this method primarily arises due to incorrect exposure conditions, when compared to larger commercial ships that mainly are moving with few and shorter idle periods...... with a radius of 11.45 cm. The drag performances in the newly applied coating condition and after one month of static immersion in natural seawater were measured using a friction disk machine (FDM). The four best performing coatings were re-examined for their drag performance after an additional 2.5 months...

  11. On the convex hull of symmetric stable processes

    CERN Document Server

    Kampf, Jürgen

    2010-01-01

    Let alpha \\in (1, 2] and X be an R^d-valued alpha-stable process with independent and symmetric components starting in 0. We consider the closure S_t of the path described by X on the interval [0, t] and its convex hull Z_t. The first result of this paper provides a formula for certain mean mixed volumes of Z_t and in particular for the expected first intrinsic volume of Z_t. The second result deals with the asymptotics of the expected volume of the stable sausage Z_t+B (where B is an arbitrary convex body with interior points) as t \\to 0.

  12. Probabilistic ultimate strength analysis of submarine pressure hulls

    Science.gov (United States)

    Cerik, Burak Can; Shin, Hyun-Kyoung; Cho, Sang-Rai

    2013-03-01

    This paper examines the application of structural reliability analysis to submarine pressure hulls to clarify the merits of probabilistic approach in respect thereof. Ultimate strength prediction methods which take the inelastic behavior of ring-stiffened cylindrical shells and hemi-spherical shells into account are reviewed. The modeling uncertainties in terms of bias and coefficient of variation for failure prediction methods in current design guidelines are defined by evaluating the compiled experimental data. A simple ultimate strength formulation for ring-stiffened cylinders taking into account the interaction between local and global failure modes and an ultimate strength formula for hemispherical shells which have better accuracy and reliability than current design codes are taken as basis for reliability analysis. The effects of randomness of geometrical and material properties on failure are assessed by a prelimnary study on reference models. By evaluation of sensitivity factors important variables are determined and comparesons are made with conclusions of previous reliability studies.

  13. INTEGRATION OF SHIP HULL ASSEMBLY SEQUENCE PLANNING, SCHEDULING AND BUDGETING

    Directory of Open Access Journals (Sweden)

    Remigiusz Romuald Iwańkowicz

    2015-02-01

    Full Text Available The specificity of the yard work requires the particularly careful treatment of the issues of scheduling and budgeting in the production planning processes. The article presents the method of analysis of the assembly sequence taking into account the duration of individual activities and the demand for resources. A method of the critical path and resource budgeting were used. Modelling of the assembly was performed using the acyclic graphs. It has been shown that the assembly sequences can have very different feasible budget regions. The proposed model is applied to the assembly processes of large-scale welded structures, including the hulls of ships. The presented computational examples have a simulation character. They show the usefulness of the model and the possibility to use it in a variety of analyses.

  14. A New Representation and Algorithm for Constructing Convex Hulls in Higher Dimensional Spaces

    Institute of Scientific and Technical Information of China (English)

    吕伟; 梁友栋

    1992-01-01

    This paper presents a new and simple scheme to describe the convex hull in Rd,which only uses three kinds of the faces of the convex hull.i.e.,the d-1-faces,d-2-faces and 0-faces.Thus,we develop and efficient new algorithm for constructing the convex hull of a finite set of points incrementally.This algorithm employs much less storage and time than that of the previously-existing approaches.The analysis of the runniing time as well as the storage for the new algorithm is also theoretically made.The algorithm is optimal in the worst case for even d.

  15. Aircraft engine-mounted camera system for long wavelength infrared imaging of in-service thermal barrier coated turbine blades

    Science.gov (United States)

    Markham, James; Cosgrove, Joseph; Scire, James; Haldeman, Charles; Agoos, Ian

    2014-12-01

    This paper announces the implementation of a long wavelength infrared camera to obtain high-speed thermal images of an aircraft engine's in-service thermal barrier coated turbine blades. Long wavelength thermal images were captured of first-stage blades. The achieved temporal and spatial resolutions allowed for the identification of cooling-hole locations. The software and synchronization components of the system allowed for the selection of any blade on the turbine wheel, with tuning capability to image from leading edge to trailing edge. Its first application delivered calibrated thermal images as a function of turbine rotational speed at both steady state conditions and during engine transients. In advance of presenting these data for the purpose of understanding engine operation, this paper focuses on the components of the system, verification of high-speed synchronized operation, and the integration of the system with the commercial jet engine test bed.

  16. Enteric coating of ibuprofen tablets (200 mg using an aqueous dispersion system

    Directory of Open Access Journals (Sweden)

    Rabia Bushra

    2010-03-01

    Full Text Available Ibuprofen is a propionic acid derivative that belongs to the class NSAIDs. Major adverse reactions associated with Ibuprofen are related to GIT and include peptic and mucosal ulcers, dyspepsia, severe gastric pain and bleeding, that results in excessive treatment failure. The goal of this study was to develop enteric coated ibuprofen tablets in order to avoid gastric mucosal irritation, diffusion of drug across mucosal lining and to let active ingredient be absorbed easily in small intestine. The formulation was developed and manufactured through the direct compression process, the simplest, easiest and most economical method of manufacturing. Enteric coating was done using an Opadry white subcoating and an aqueous coating dispersion of Acryl-Eze. Enteric coated formulation was subjected to disintegration and dissolution tests by placing in 0.1 M hydrochloric acid for 2 h and then 1 h in phosphate buffer with a pH of 6.8. About 0.04% of drug was released in the acidic phase and 99.05% in the basic medium. These results reflect that ibuprofen can be successfully enteric coated in order to prevent its release in the stomach and facilitate rapid release of the drug in the duodenum, due to the presence of superdisintegrant. Formulating this enteric coated tablets could increase patient compliance by decreasing adverse drug reactions (ADR S associated with Ibuprofen therapy.Ibuprofeno é um derivado do ácido propiônico, que pertence à classe dos fármacos não-esteróides (AINES. As principais reações adversas associadas com o ibuprofeno se referem àquelas do trato gastrintestinal (TGI, como úlceras pépticas e da mucosa, dispepsia, dor gástrica grave e sangramento, que resultam em muitas falhas de tratamento. O objetivo do estudo foi desenvolver comprimidos revestidos de ibuprofeno que impeçam a irritação da mucosa gástrica, difusão do fármaco através da mucosa e permitam, facilmente, a absorção do princípio ativo do intestino

  17. Tank tests of a family of flying-boat hulls

    Science.gov (United States)

    Shoemaker, James M; Parkinson, John B

    1934-01-01

    This report presents towing tests made in the N.A.C.A. tank of a parent form and five variations of a flying-boat hull. The beams of two of the derived forms were made the same as that of the parent and the lengths changed by increasing and decreasing the spacing of stations. The lengths of the two others of the derived forms were made the same as that of the parent while the beams were changed by increasing and decreasing the spacing of buttocks, all other widths being changed in proportion. The remaining derived form has the same length and beam as the parent, but the lines of the forebody were altered to give a planing bottom with no longitudinal curvature forward of the step. The test data were analyzed to determine the minimum resistance and the angle at which it occurs for all speeds and loads. The results of this analysis are given in the form of non dimensional curves for each model. The effect of variation in over-all size, as indicated by a "complete" test on any given hull, is pointed out. The effect of changing length alone by the spacing of buttocks, as well as the effects of the changes in length-beam ratio and longitudinal curvature that result from these operations are discussed. The difficulties encountered in interpreting test results of systematic families derived by the method used are emphasized. Further studies are suggested in which changes in the variable under consideration would not be obscured by secondary changes in other important variables.

  18. Do adhesive systems leave resin coats on the surfaces of the metal matrix bands? An adhesive remnant characterization.

    Science.gov (United States)

    Arhun, Neslihan; Cehreli, Sevi Burcak

    2013-01-01

    Reestablishing proximal contacts with composite resins may prove challenging since the applied adhesives may lead to resin coating that produces additional thickness. The aim of this study was to investigate the surface of metal matrix bands after application of adhesive systems and blowing or wiping off the adhesive before polymerization. Seventeen groups of matrix bands were prepared. The remnant particles were characterized by energy dispersive spectrum and scanning electron microscopy. Total etch and two-step self-etch adhesives did not leave any resin residues by wiping and blowing off. All-in-one adhesive revealed resin residues despite wiping off. Prime and Bond NT did not leave any remnant with compomer. Clinicians must be made aware of the consequences of possible adhesive remnants on matrix bands that may lead to a defective definitive restoration. The adhesive resin used for Class II restorations may leave resin coats on metal matrix bands after polymerization, resulting in additional thickness on the metal matrix bands and poor quality of the proximal surface of the definitive restoration when the adhesive system is incorporated in the restoration.

  19. Polymeric coatings for a multiple-unit pulsatile delivery system: preliminary study on free and applied films.

    Science.gov (United States)

    Maroni, Alessandra; Del Curto, Maria Dorly; Cerea, Matteo; Zema, Lucia; Foppoli, Anastasia; Gazzaniga, Andrea

    2013-01-20

    In order to adapt a previously described swellable/erodible pulsatile delivery system to a multiple-unit configuration, insoluble films with adequate permeability and flexibility were proposed for application to its functional hydroxypropyl methylcellulose (HPMC) layer. By slowing down the penetration of water into the system, such films would be expected to improve the relevant effectiveness in delaying the onset of release without possibly impacting on the mechanism involved. Free films of Eudragit(®)NE containing differing amounts (10-20%) of a superdisintegrant, i.e. Explotab(®)V17, Ac-Di-Sol(®), Kollidon(®)CL or Kollidon(®)CL-M, were prepared by spraying technique and evaluated for hydration, permeability and tensile properties. The hydration and permeability characteristics were enhanced by the addition of the superdisintegrants, generally as a function of their concentration. Explotab(®)V17 was shown particularly useful to increase the film permeability. Moreover, it exerted a minor impact on the advantageous tensile properties of the acrylic polymer, especially in the wet state. Based on these results and on a preliminary release study performed with two-layer devices, the Eudragit(®)NE film with Explotab(®)V17 at the highest investigated percentage was identified as a potential formulation candidate for being applied to HPMC-coated cores thus allowing the onset of release to effectively be delayed by coatings of reduced thickness.

  20. Advanced Materials for Aircraft Propulsion Systems. Phase I. Investigation of Corrosion Resistant Coatings for Service at 3000 F and above.

    Science.gov (United States)

    diffusion barrier between the coating and metallic substrate. Preliminary studies were limited to development of coatings that would be applicable to the protection of Ni-base and Co-base superalloys. (Author)

  1. The friction coefficient evolution of a MoS2/WC multi-layer coating system during sliding wear

    Science.gov (United States)

    Chan, T. Y.; Hu, Y.; Gharbi, Mohammad M.; Politis, D. J.; Wang, L.

    2016-08-01

    This paper discusses the evolution of friction coefficient for the multi-layered Molybdenum Disulphide (MoS2) and WC coated substrate during sliding against Aluminium AA 6082 material. A soft MoS2 coating was prepared over a hard WC coated G3500 cast iron tool substrate and underwent friction test using a pin-on-disc tribometer. The lifetime of the coating was reduced with increasing load while the Aluminium debris accumulated on the WC hard coating surfaces, accelerated the breakdown of the coatings. The lifetime of the coating was represented by the friction coefficient and the sliding distance before MoS2 coating breakdown and was found to be affected by the load applied and the wear mechanism.

  2. Evaluation of environmental safety concentrations of DMSA Coated Fe2O3-NPs using different assay systems in nematode Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Qiuli Wu

    Full Text Available Dimercaptosuccinic acid (DMSA coating improves the uptake efficiency presumably by engendering the Fe(2O(3-NPs. In the present study, we investigated the possible environmental safety concentrations of Fe(2O(3-NPs using different assay systems in nematode Caenorhabditis elegans with lethality, development, reproduction, locomotion behavior, pharyngeal pumping, defecation, intestinal autofluorescence and reactive oxygen species (ROS production as the endpoints. After exposure from L4-larvae for 24-hr, DMSA coated Fe(2O(3-NPs at concentrations more than 50 mg/L exhibited adverse effects on nematodes. After exposure from L1-larvae to adult, DMSA coated Fe(2O(3-NPs at concentrations more than 500 μg/L had adverse effects on nematodes. After exposure from L1-larvae to day-8 adult, DMSA coated Fe(2O(3-NPs at concentrations more than 100 μg/L resulted in the adverse effects on nematodes. Accompanied with the alterations of locomotion behaviors, ROS production was pronouncedly induced by exposure to DMSA coated Fe(2O(3-NPs in the examined three assay systems, and the close associations of ROS production with lethality, growth, reproduction, locomotion behavior, pharyngeal pumping, defecation, or intestinal autofluorescence in nematodes exposed to DMSA coated Fe(2O(3-NPs were confirmed by the linear regression analysis. Moreover, mutations of sod-2 and sod-3 genes, encoding Mn-SODs, showed more susceptible properties than wild-type when they were used for assessing the DMSA coated Fe(2O(3-NPs-induced toxicity, and the safety concentrations for DMSA coated Fe(2O(3-NPs should be defined as concentrations lower than 10 μg/L in sod-2 and sod-3 mutant nematodes.

  3. Note: Automatic layer-by-layer spraying system for functional thin film coatings

    Science.gov (United States)

    Seo, Seongmin; Lee, Sangmin; Park, Yong Tae

    2016-03-01

    In this study, we have constructed an automatic spray machine for producing polyelectrolyte multilayer films containing various functional materials on wide substrates via the layer-by-layer (LbL) assembly technique. The proposed machine exhibits advantages in terms of automation, process speed, and versatility. Furthermore, it has several features that allow a fully automated spraying operation, such as various two-dimensional spraying paths, control of the flow rate and operating speed, air-assist fan-shaped twin-fluid nozzles, and an optical display. The robot uniformly sprays aqueous mixtures containing complementary (e.g., oppositely charged, capable of hydrogen bonding, or capable of covalent bonding) species onto a large-area substrate. Between each deposition of opposite species, samples are spray-rinsed with deionized water and blow-dried with air. The spraying, rinsing, and drying areas and times are adjustable by a computer program. Twenty-bilayer flame-retardant thin films were prepared in order to compare the performance of the spray-assisted LbL assembly with a sample produced by conventional dipping. The spray-coated film exhibited a reduction of afterglow time in vertical flame tests, indicating that the spray-LbL technique is a simple method to produce functional thin film coatings.

  4. Coatings Technology Integration Office (CTIO)

    Data.gov (United States)

    Federal Laboratory Consortium — CTIO serves as the Air Force's central resource for aircraft coating systems and their applications. CTIO's primary objectives are pollution prevention and improved...

  5. Influence of Material Coating on the Heat Transfer in a Layered Cu-SiC-Cu Systems

    Directory of Open Access Journals (Sweden)

    Strojny-Nędza A.

    2017-06-01

    Full Text Available This paper describes the process of obtaining Cu-SiC-Cu systems by way of spark plasma sintering. A monocrystalline form of silicon carbide (6H-SiC type was applied in the experiment. Additionally, silicon carbide samples were covered with a layer of tungsten and molybdenum using chemical vapour deposition (CVD technique. Microstructural examinations and thermal properties measurements were performed. A special attention was put to the metal-ceramic interface. During annealing at a high temperature, copper reacts with silicon carbide. To prevent the decomposition of silicon carbide two types of coating (tungsten and molybdenum were applied. The effect of covering SiC with the aforementioned elements on the composite’s thermal conductivity was analyzed. Results were compared with the numerical modelling of heat transfer in Cu-SiC-Cu systems. Certain possible reasons behind differences in measurements and modelling results were discussed.

  6. Coatings for improved corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.

    1992-05-01

    Several coating approaches are being developed to resist attack in coal-fired environments and thereby minimize corrosion of underlying substrate alloys and extend the time for onset of breakaway corrosion. In general, coating systems can be classified as either diffusion or overlay type, which are distinguished principally by the method of deposition and the structure of the resultant coating-substrate bond. The coating techniques examined are pack cementation, electrospark deposition, physical and chemical vapor deposition, plasma spray, and ion implantation. In addition, ceramic coatings are used in some applications.

  7. Experimental Study on Ship Performaces of a Catamaran with Asymmetric Demi-Hulls

    National Research Council Canada - National Science Library

    Hironori Yasukawa; Noritaka Hirata; Shuji Ikezoe; Yuichi Hirata

    2012-01-01

      To capture the ship performances of a catamaran with asymmetric demi-hulls, tank tests were carried out such as resistance test in still water, measurement test of wave height of wash, seakeeping...

  8. Anomalous dispersion of Lagrangian particles in local regions of turbulent flows revealed by convex hull analysis

    CERN Document Server

    Pratt, J; Mueller, W -C; Chapman, S C; Watkins, N W

    2014-01-01

    Local regions of anomalous particle dispersion, and intermittent events that occur in turbulent flows can greatly influence the global statistical description of the flow. These local behaviors can be identified and analyzed by comparing the growth of neighboring convex hulls of Lagrangian tracer particles. Although in our simulations of homogeneous turbulence the convex hulls generally grow in size, after the Lagrangian particles that define the convex hulls begin to disperse, our analysis reveals short periods when the convex hulls of the Lagrangian particles shrink, evidence that particles are not dispersing simply. Shrinkage can be associated with anisotropic flows, since it occurs most frequently in the presence of a mean magnetic field or thermal convection. We compare dispersion between a wide range of statistically homogeneous and stationary turbulent flows ranging from homogeneous isotropic Navier-Stokes turbulence over different configurations of magnetohydrodynamic turbulence and Boussinesq convect...

  9. Three-Dimensional Mathematical Investigation of Dynamic and Hydrostatic Pressure Distributions on Planing Hulls

    Directory of Open Access Journals (Sweden)

    Parviz Ghadimi

    2013-01-01

    Full Text Available A mathematical model is utilized in order to calculate three-dimensional pressure distributions on planing hulls. This type of modeling is able to determine the hydrodynamic and hydrostatic pressures acting on the bottom of these hulls. As a result, the total 3-dimensional pressure exerted on the planing hull as a sum of hydrostatic and hydrodynamic pressures can be evaluated. Empirical equations introduced in previous works have been used as the fundamentals for the present mathematical modeling method. The obtained results are compared against available experimental results and results of empirical equations in order to validate the proposed method. The outcome of the -squared tests conducted on these comparisons shows favorable accuracy of the results. After evaluation of hydrodynamic pressure, the effects of trim and deadrise angles and wetted length on the 3-dimensional pressure distribution are analyzed. Finally, the total pressure on planing hull and the effect of velocity coefficients are studied.

  10. The influence of shallow water and hull form variations on inland ship resistance

    NARCIS (Netherlands)

    Rotteveel, E.; Hekkenberg, R.G.

    2015-01-01

    Effects of a hull form variation and shallow water on a 110-meter inland ship are presented as preliminary results of the Top Ships project, which is initiated in order to improve inland ship design tools and design guidelines.

  11. The influence of shallow water and hull form variations on inland ship resistance

    NARCIS (Netherlands)

    Rotteveel, E.; Hekkenberg, R.G.

    2015-01-01

    Effects of a hull form variation and shallow water on a 110-meter inland ship are presented as preliminary results of the Top Ships project, which is initiated in order to improve inland ship design tools and design guidelines.

  12. WAVE MAKING COMPUTATION IN TIME DOMAIN FOR MULTI-HULL SHIPS

    Institute of Scientific and Technical Information of China (English)

    LI Guo-an; YE Heng-kui

    2006-01-01

    A method of three-dimensional time domain Green function satisfying linear conditions at free surface and body surface boundary was employed to analyze the wave resistance and wave profile of a displacement multi-hull ship. The wave profile induced by a moving time domain point source was compared with those by a Havelock source, and satisfactory results were obtained. The panel method based on the time domain source distribution on the ship mean wetted hull surface was used to perform the wave making com- putations for mono-hull ships, catamaran and trimaran. Reasonable results were also obtained. Using the numerical method the wave profile simulations of multi-hull ships for a given Froude number were conducted.

  13. A Robot for the Unsupervised Grit-Blasting of Ship Hulls

    Directory of Open Access Journals (Sweden)

    Daniel Souto

    2012-09-01

    Full Text Available This paper describes the design and the control architecture of an unsupervised robot developed for grit blasting ship hulls in shipyards. Grit blasting is a very common and environmentally unfriendly operation, required for preparing metallic surfaces for painting operations. It also implies very unhealthy and hazardous working conditions for the operators that must carry it out. The robot presented here has been designed to reduce the environmental impact of these operations and completely eliminate the health associated risks for the operators. It is based on a double frame main body with magnetic legs that are able to avoid the accumulation of ferromagnetic dust during its operation. The control system presents a layered structure with four layers that are physically distributed into two separate components in order to facilitate different operational modes as well as to increase the safety requirements of the system. A low-level control component has been implemented on the robotic unit itself, and a mission planning and control component has been developed on a base station that is also used for interaction with the operator, when the monitoring of the robot's operation is required. This base station component contains three layers of the control system that permit the manual, semiautonomous and autonomous operation of the whole system. A prototype of the robot has been implemented and tested in realistic environments, ascertaining that the design and the control system are perfectly suited to the functions which the robot must carry out.

  14. A Robot for the Unsupervised Grit-Blasting of Ship Hulls

    Directory of Open Access Journals (Sweden)

    Daniel Souto

    2012-09-01

    Full Text Available This paper describes the design and the control architecture of an unsupervised robot developed for grit blasting ship hulls in shipyards. Grit blasting is a very common and environmentally unfriendly operation, required for preparing metallic surfaces for painting operations. It also implies very unhealthy and hazardous working conditions for the operators that must carry it out. The robot presented here has been designed to reduce the environmental impact of these operations and completely eliminate the health associated risks for the operators. It is based on a double frame main body with magnetic legs that are able to avoid the accumulation of ferromagnetic dust during its operation. The control system presents a layered structure with four layers that are physically distributed into two separate components in order to facilitate different operational modes as well as to increase the safety requirements of the system. A low‐level control component has been implemented on the robotic unit itself, and a mission planning and control component has been developed on a base station that is also used for interaction with the operator, when the monitoring of the robot’s operation is required. This base station component contains three layers of the control system that permit the manual, semiautonomous and autonomous operation of the whole system. A prototype of the robot has been implemented and tested in realistic environments, ascertaining that the design and the control system are perfectly suited to the functions which the robot must carry out.

  15. Opportunities for functional oxides in yttrium oxide-titanium oxide-zirconium oxide system: Applications for novel thermal barrier coatings

    Science.gov (United States)

    Francillon, Wesley

    This dissertation is an investigation of materials and processed under consideration for next generation thermal structural oxides with potential applications as thermal barrier coatings; wherein, high temperature stability and mechanical properties affect durability. Two notable next generation materials systems under investigation are pyrochlore and co-doped zirconia oxides. The motivation for this work is based on current limitations of the currently used thermal barrier material of yttria stabilized zirconia (YSZ) deposited by the plasma spray processes. The rapid quenching associated with the plasma spray process, results in a metastable structure that is a non-transformable tetragonal structure in the yttria partially stabilized zirconia system rather than the equilibrium anticipated two phase mixture of cubic and monoclinic phases. It has been shown that this metastable structure offers enhanced toughness and thus durability during thermomechanical cycling from the operating temperatures in excess of 1000C to ambient. However, the metastable oxides are susceptible to partitioning at temperatures greater than 1200C, thus resulting in a transformation of the tetragonal phase oxides. Transformations of the tetragonal prime phase into the parent cubic and tetragonal prime phase result in coating degradation. Several of the emerging oxides are based on rare earth additions to zirconia. However, there is limited information of the high temperature stability of these oxide coatings and more notably these compositions exhibit limited toughness for durable performance. A potential ternary composition based on the YSZ system that offers the ability to tailor the phase structure is based YO1.5-TiO2 -ZrO2. The ternary of YO1.5-TiO2-ZrO 2 has the current TBC composition of seven molar percent yttria stabilized zirconia, pyrochlore phase oxide and zirconia doped with yttria and titania additions (Ti-YSZ). The Ti-YSZ phase field is of interest because at equilibrium it is

  16. Physicochemical changes in the hull of corn grains during their alkaline cooking.

    Science.gov (United States)

    González, Regino; Reguera, Edilso; Mendoza, Leobardo; Figueroa, Juan Manuel; Sánchez-Sinencio, Feliciano

    2004-06-16

    The alkaline cooking of corn in a solution of Ca(OH)2 to produce corn-based foods is oriented to make corn proteins available, to incorporate Ca to the cooked grains, and also to remove the corn hull. This process (nixtamalization) is known in Mexico and Guatemala from prehispanic times; however, the effect of the alkaline cooking on the corn hull remains poorly documented. In this work, the physicochemical changes that take place in the corn hull during its cooking in a saturated solution of Ca(OH)2 were studied using infrared, X-ray diffraction, 13C cross-polarization/magic-angle spinning (CP/MAS) NMR, confocal imaging microscopy, differential scanning calorimetry, and thermogravimetry techniques. The main effect of this treatment on the hull is the removal of hemicelluloses and lignin, increasing the hull permeability and, as a consequence, facilitating the entry of the alkaline solution into the corn kernel. No significant changes were observed in the cellulose fiber network, which remains as native cellulose I, with a crystalline index, according to 13C CP/MAS NMR spectra, of 0.60. The alkaline treatment does not allow the cellulose fibers to swell and their regeneration in the form of cellulose(II). It seems any attempt to make use of the Ca binding capacity of the hull to increase the Ca availability in nixtamalized corn-based foods requires a separated treatment for the hull and kernel. On alkaline cooking, the hull hemicellulose fraction dissolves, losing its ability to bind Ca as a way to incorporate this element into foods elaborated from nixtamalized corn.

  17. David Hull's generalized natural selection as an explanation for scientific change

    Science.gov (United States)

    Little, Michelle Yvette

    2001-10-01

    Philosophers of science such as Karl Popper and Thomas Kuhn have employed evolutionary idiom in describing scientific change. In Science as a Process (1988) Hull makes evolutionary theory explanatorily applicable. He modifies key evolutionary terms in order that both biological evolution and scientific change are instances of a general selection process. According to Hull, because of naturally-existing competition for credit among researchers and the professional lineages they constitute, scientists are constrained to cooperate and collaborate. This process entails two important philosophical consequences. First, it allows for a natural justification of why the sciences can provide objective empirical knowledge. Second, appreciating its strength means that a philosophical analysis of scientific change is solidly difficult features to combine. I work on strengthening two weaknesses in Hull's arguments. First, operating in his analysis is an unexplicated notion of ``information'' running parallel to the equally opaque notion of genetic information. My third chapter provides a clear account of ``genetic information'' whose usefulness extends beyond the assistance it can render Hull as a clear concept is needed in biological contexts as well. The fourth and fifth chapters submit evidence of scientific change from radio astronomy. Hull insists on empirical backing for philosophical theses but his own book stands to suffer from selection effects as it offers cases drawn from a single subspecialty in the biological sciences. I found that in the main scientists and the change they propel accords well with Hull's explanation. However, instances of major change reveal credit- and resource-sharing to a degree contrary with what Hull would expect. My conclusion is that the naturalness of competition, instantiated during the course of standardized and relatively ``normal'' scientific research, is not the norm during periods of new research and its uncertain standards of

  18. Oat hulls treated with alkaline hydrogen peroxide associated with extrusion as fiber source in cookies

    OpenAIRE

    Galdeano,Melícia Cintia; Grossmann,Maria Victória Eiras

    2006-01-01

    Cookies were prepared with the replacement of 20% of wheat flour by chemically (alkaline hydrogen peroxide) and physically (extrusion) treated oat hulls, with the objective to investigate the possibility of use of this modified material. Cookies elaborated with the untreated hulls were used as control. Cookies were evaluated for their physical (spread ratio, specific volume and color) and sensory characteristics, and no difference was detected (p

  19. EFFECT OF NITROGEN FERTILIZATION ON GRAIN YIELD AND QUALITY OF HULLED AND HULLESS SPRING OATS

    OpenAIRE

    2015-01-01

    A field trial was set up in 2014 the growing season at the Bc Institute’s experimental field in Botinec aiming to investigate the effect of four levels of nitrogen fertilization on grain yield, test weight, thousand kernel weight and plant height of eight hulled and two hulless oat genotypes. Significant differences were found out among nitrogen fertilization levels as well as among the eight hulled genotypes for all traits. The interaction genotype × N fertilization was not significant. Sign...

  20. Morbus Coats

    Science.gov (United States)

    Förl, B.; Schmack, I.; Grossniklaus, H.E.; Rohrschneider, K.

    2010-01-01

    Der fortgeschrittene Morbus Coats stellt im Kleinkindalter eine der schwierigsten Differenzialdiagnosen zum Retinoblastom dar. Wir beschreiben die klinischen und histologischen Befunde zweier Jungen im Alter von 9 und 21 Monaten mit einseitiger Leukokorie. Trotz umfassender Diagnostik mittels Narkoseuntersuchung, MRT und Ultraschall konnte ein Retinoblastom nicht sicher ausgeschlossen werden, und es erfolgte eine Enukleation. Histologisch wurde die Diagnose eines Morbus Coats gesichert. Da eine differenzialdiagnostische Abgrenzung zwischen Morbus Coats und Retinoblastom schwierig sein kann, halten wir in zweifelhaften Fällen auch angesichts der eingeschränkten Visusprognose und potenzieller Sekundärkomplikationen beim fortgeschrittenen Morbus Coats eine Enukleation für indiziert. PMID:18299842