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Sample records for chrome oxide refractory

  1. Low-Chrome/Chrome Free Refractories for Slagging Gasifiers

    International Nuclear Information System (INIS)

    Bennett, J.P.; Kwong, K.-S.; Powell, C.P.; Thomas, H.; Petty, A.V. Jr.

    2007-01-01

    Gasifiers are containment vessels used to react carbon-containing materials with oxygen and water, producing syngas (CO and H2) that is used in chemical and power production. It is also a potential source of H2 in a future hydrogen economy. Air cooled slagging gasifiers are one type of gasifier, operating at temperatures from 1275-1575 C and at pressures of 400 psi or higher. They typically use coal or petroleum coke as the carbon source, materials which contain ash impurities that liquefy at the gasification temperatures, producing liquid slag in quantities of 100 or more tons/day, depending on the carbon fed rate and the percent ash present in the feedstock. The molten slag is corrosive to refractory linings, causing chemical dissolution and spalling. The refractory lining is composed of chrome oxide, alumina, and zirconia; and is replaced every 3-24 months. Gasifier users would like greater on-line availability and reliability of gasifier liners, something that has impacted gasifier acceptance by industry. Research is underway at NETL to improve refractory service life and to develop a no-chrome or low-chrome oxide alternative refractory liner. Over 250 samples of no- or low-chrome oxide compositions have been evaluated for slag interactions by cup testing; with potential candidates for further studies including those with ZrO2, Al2O3, and MgO materials. The development of improved liner materials is necessary if technologies such as IGCC and DOE's Near Zero Emissions Advanced Fossil Fuel Power Plant are to be successful and move forward in the marketplace

  2. Improvement of uptake of chrome tan on hide protein by basic oxides

    International Nuclear Information System (INIS)

    Nashya, E.H.A.; Aggiagh, A.E.; Khedra, M.H.; El-Sayeda, N.H.E.

    2005-01-01

    Three basic oxides were used to improve uptake of chrome tan as well as shrinkage temperature of the tanned leather. In addition, the skin quality is one of the most important factors taking into consideration. Three basic oxides, named magnesium oxide, manganese oxide and sodium bicarbonate. The process was optimized taking into the account the shaking rate, chrome concentration (%), initial ph, basic oxides concentration, temperature and contact time. The optimum conditions for exhaustion, fixation, shrinkage temperature as well as skin quality showed that agitation rate of 150 rpm, chrome concentration of 16%, initial ph of 2.5, basic oxide concentration of 4% magnesium oxide, temperature of 35 degree C and contact time of 24 hr. The best results obtained are 88% exhaustion, 90.03% fixation and 109 degree C shrinkage temperature in aqueous medium

  3. Chemometrics models for assessment of oxidative stress risk in chrome-electroplating workers.

    Science.gov (United States)

    Zendehdel, Rezvan; Shetab-Boushehri, Seyed Vahid; Azari, Mansoor R; Hosseini, Vajihe; Mohammadi, Hamidreza

    2015-04-01

    Oxidative stress is the main cause of hexavalant chromium-induced damage in chrome electroplating workers. The main goal of this study is toxicity analysis and the possibility of toxicity risk categorizing in the chrome electroplating workers based on oxidative stress parameters as prognostic variables. We assessed blood chromium levels and biomarkers of oxidative stress such as lipid peroxidation, thiol (SH) groups and antioxidant capacity of plasma. Data were subjected to principle component analysis (PCA) and artificial neuronal network (ANN) to obtain oxidative stress pattern for chrome electroplating workers. Blood chromium levels increased from 4.42 ppb to 10.6 ppb. Induction of oxidative stress was observed by increased in lipid peroxidation (22.38 ± 10.47 μM versus 14.74 ± 4.82 μM, p chrome electroplaters. The result showed multivariate modeling can be interpreted as the induced biochemical toxicity in the workers exposed to hexavalent chromium. Different occupation groups were assessed on the basis of risk level of oxidative stress which could further justify proceeding engineering control measures.

  4. Weight of Polyethylene Wear Particles is Similar in TKAs with Oxidized Zirconium and Cobalt-chrome Prostheses

    Science.gov (United States)

    Kim, Jun-Shik; Huh, Wansoo; Lee, Kwang-Hoon

    2009-01-01

    Background The greater lubricity and resistance to scratching of oxidized zirconium femoral components are expected to result in less polyethylene wear than cobalt-chrome femoral components. Questions/purposes We examined polyethylene wear particles in synovial fluid and compared the weight, size (equivalent circle diameter), and shape (aspect ratio) of polyethylene wear particles in knees with an oxidized zirconium femoral component with those in knees with a cobalt-chrome femoral component. Patients and Methods One hundred patients received an oxidized zirconium femoral component in one knee and a cobalt-chrome femoral component in the other. There were 73 women and 27 men with a mean age of 55.6 years (range, 44–60 years). The minimum followup was 5 years (mean, 5.5 years; range, 5–6 years). Polyethylene wear particles were analyzed using thermogravimetric methods and scanning electron microscopy. Results The weight of polyethylene wear particles produced at the bearing surface was 0.0223 ± 0.0054 g in 1 g synovial fluid in patients with an oxidized zirconium femoral component and 0.0228 ± 0.0062 g in patients with a cobalt-chrome femoral component. Size and shape of polyethylene wear particles were 0.59 ± 0.05 μm and 1.21 ± 0.24, respectively, in the patients with an oxidized zirconium femoral component and 0.52 ± 0.03 μm and 1.27 ± 0.31, respectively, in the patients with a cobalt-chrome femoral component. Knee Society knee and function scores, radiographic results, and complication rate were similar between the knees with an oxidized zirconium and cobalt-chrome femoral component. Conclusions The weight, size, and shape of polyethylene wear particles were similar in the knees with an oxidized zirconium and a cobalt-chrome femoral component. We found the theoretical advantages of this surface did not provide the actual advantage. Level of Evidence Level I, therapeutic study. See the guidelines for Authors for a complete

  5. Mid-term survivorship and clinical outcomes of cobalt-chrome and oxidized zirconium on highly crosslinked polyethylene.

    Science.gov (United States)

    Petis, Stephen M; Vasarhelyi, Edward M; Lanting, Brent A; Howard, James L; Naudie, Douglas D R; Somerville, Lyndsay E; McCalden, Richard W

    2016-02-01

    The choice of bearing articulation for total hip arthroplasty in younger patients is amenable to debate. We compared mid-term patient-reported outcomes and survivorship across 2 different bearing articulations in a young patient cohort. We reviewed patients with cobalt-chrome or oxidized zirconium on highly crosslinked polyethylene who were followed prospectively between 2004 and 2012. Kaplan-Meier analysis was used to determine predicted cumulative survivorship at 5 years with all-cause and aseptic revisions as the outcome. We compared patient-reported outcomes, including the Harris hip score (HHS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Short-form 12 (SF-12) scores. A total of 622 patients were followed during the study period. Mean follow-up was 8.2 (range 2.0-10.6) years for cobalt-chrome and 7.8 (range 2.1-10.7) years for oxidized zirconium. Mean age was 54.9 ± 10.6 years for cobalt-chrome and 54.8 ± 10.7 years for oxidized zirconium. Implant survivorship was 96.0% (95% confidence interval [CI] 94.9%-97.1%) for cobalt-chrome and 98.7% (95% CI 98.0%-99.4%) for oxidized zirconium on highly crosslinked polyethylene for all-cause revisions, and 97.2% (95% CI 96.2%-98.2%) for cobalt-chrome and 99.0% (95% CI 98.4%-99.6%) for oxidized zirconium for aseptic revisions. An age-, sex- and diagnosis-matched comparison of the HHS, WOMAC and SF-12 scores demonstrated no significant changes in clinical outcomes across the groups. Both bearing surface couples demonstrated excellent mid-term survivorship and outcomes in young patient cohorts. Future analyses on wear and costs are warranted to elicit differences between the groups at long-term follow-up.

  6. Autoradiographic study of corrosion of refractories

    International Nuclear Information System (INIS)

    Lisenenkova, S.B.; Kucheryavyi, M.N.; Bursteva, T.A.

    1988-01-01

    A comparative study was made of the character of the interaction between a container-glass melt consisting of sodium calcium silicate and refractories in various furnace sections using an autoradiographic method. Static tests were conducted on specimens of the following refractories: chrome-aluminum-zircon, Bakor 41, corundum, a high alumina refractory, and a refractory based on tin dioxide. The specimens were activated by calcium 45. Autoradiography and photomicrography indicated that an intrinsic feature of all refractories was that calcium from the melt penetrated the refractories along the weak link; for fused-cast refractories, the glass phase; and for sintered refractories, through the binder and cracks

  7. Degradation of Alumina and Magnesia Chrome refractory bricks in Portland cement kiln – Corrected version*

    Directory of Open Access Journals (Sweden)

    Ben Addi K.

    2014-05-01

    Full Text Available In cement plants, the refractory products are particularly confronted to partially liquid oxide phases at temperature ranging between 900°C and 1700°C. All constituents of these products have to resist not only to thermal constraints, but also to the thermochemical solicitations which result from contact material/coating. In order to study the phenomenon of degradation of refractory bricks in cement kilns and to identify the causes of their degradation, we proceed to the examination of industrial cases in cement kiln. Many chemical tests of the degraded refractory bricks have been done and the results acquired were compared to the ones not used. The analysis of the results is doing using different techniques (Loss of ignition, X-ray Fluorescence, X-ray Diffraction. The results show that the degradation of the used bricks in the clinkering and cooling zone is due to the infiltration of aggressive elements such us sulphur, alkali (Na2O, K2O .... The chemical interaction between the Portland clinker phases and refractory material has also an importance on the stability of the coating and consequently on the life of the refractories.

  8. Study on creep-fatigue evaluation of chrome-molybdenum steel

    International Nuclear Information System (INIS)

    Aoto, Kazumi; Wada, Yusaku

    1993-01-01

    Though chrome-molybdenum steel has quite different basic material properties from austenitic stainless steel, the life fraction rule based on an advanced ductility exhaustion theory proposed for SUS304 is able to give proper prediction for creep-fatigue life of chrome-molybdenum steel. The applicability of the present evaluation method to chrome-molybdenum steel is validated by both mechanical study and micro-structural observation. The mechanism of creep-fatigue failure of Mod.9Cr-1Mo(NT) is one of the most controversial subjects among researchers. However, it is clarified in this report that creep-fatigue damage of this material under actual loading conditions is dominated by creep-cavitation of grain boundaries as same way as that of austenitic stainless steel. Furthermore, for the life reduction of low cycle fatigue of chrome-molybdenum steel with compression-side strain hold, both effects of mean stress and oxide-wedge are denied and it is insisted that the acceleration of fatigue-crack propagation is occurred by oxide-progress location and its thickness. (author)

  9. Novel Chemical Process for Producing Chrome Coated Metal

    Directory of Open Access Journals (Sweden)

    Christopher Pelar

    2018-01-01

    Full Text Available This work demonstrates that a version of the Reduction Expansion Synthesis (RES process, Cr-RES, can create a micron scale Cr coating on an iron wire. The process involves three steps. I. A paste consisting of a physical mix of urea, chrome nitrate or chrome oxide, and water is prepared. II. An iron wire is coated by dipping. III. The coated, and dried, wire is heated to ~800 °C for 10 min in a tube furnace under a slow flow of nitrogen gas. The processed wires were then polished and characterized, primarily with scanning electron microscopy (SEM. SEM indicates the chrome layer is uneven, but only on the scale of a fraction of a micron. The evidence of porosity is ambiguous. Elemental mapping using SEM electron microprobe that confirmed the process led to the formation of a chrome metal layer, with no evidence of alloy formation. Additionally, it was found that thickness of the final Cr layer correlated with the thickness of the precursor layer that was applied prior to the heating step. Potentially, this technique could replace electrolytic processing, a process that generates carcinogenic hexavalent chrome, but further study and development is needed.

  10. Novel Chemical Process for Producing Chrome Coated Metal.

    Science.gov (United States)

    Pelar, Christopher; Greenaway, Karima; Zea, Hugo; Wu, Chun-Hsien; Luhrs, Claudia C; Phillips, Jonathan

    2018-01-05

    This work demonstrates that a version of the Reduction Expansion Synthesis (RES) process, Cr-RES, can create a micron scale Cr coating on an iron wire. The process involves three steps. I. A paste consisting of a physical mix of urea, chrome nitrate or chrome oxide, and water is prepared. II. An iron wire is coated by dipping. III. The coated, and dried, wire is heated to ~800 °C for 10 min in a tube furnace under a slow flow of nitrogen gas. The processed wires were then polished and characterized, primarily with scanning electron microscopy (SEM). SEM indicates the chrome layer is uneven, but only on the scale of a fraction of a micron. The evidence of porosity is ambiguous. Elemental mapping using SEM electron microprobe that confirmed the process led to the formation of a chrome metal layer, with no evidence of alloy formation. Additionally, it was found that thickness of the final Cr layer correlated with the thickness of the precursor layer that was applied prior to the heating step. Potentially, this technique could replace electrolytic processing, a process that generates carcinogenic hexavalent chrome, but further study and development is needed.

  11. Two-Step Oxidation of Refractory Gold Concentrates with Different Microbial Communities.

    Science.gov (United States)

    Wang, Guo-Hua; Xie, Jian-Ping; Li, Shou-Peng; Guo, Yu-Jie; Pan, Ying; Wu, Haiyan; Liu, Xin-Xing

    2016-11-28

    Bio-oxidation is an effective technology for treatment of refractory gold concentrates. However, the unsatisfactory oxidation rate and long residence time, which cause a lower cyanide leaching rate and gold recovery, are key factors that restrict the application of traditional bio-oxidation technology. In this study, the oxidation rate of refractory gold concentrates and the adaption of microorganisms were analyzed to evaluate a newly developed two-step pretreatment process, which includes a high temperature chemical oxidation step and a subsequent bio-oxidation step. The oxidation rate and recovery rate of gold were improved significantly after the two-step process. The results showed that the highest oxidation rate of sulfide sulfur could reach to 99.01 % with an extreme thermophile microbial community when the pulp density was 5%. Accordingly, the recovery rate of gold was elevated to 92.51%. Meanwhile, the results revealed that moderate thermophiles performed better than acidophilic mesophiles and extreme thermophiles, whose oxidation rates declined drastically when the pulp density was increased to 10% and 15%. The oxidation rates of sulfide sulfur with moderate thermophiles were 93.94% and 65.73% when the pulp density was increased to 10% and 15%, respectively. All these results indicated that the two-step pretreatment increased the oxidation rate of refractory gold concentrates and is a potential technology to pretreat the refractory sample. Meanwhile, owing to the sensitivity of the microbial community under different pulp density levels, the optimization of microbial community in bio-oxidation is necessary in industry.

  12. Electrochemical regeneration of chrome etching solution

    NARCIS (Netherlands)

    Andel, van Y.; Janssen, L.J.J.

    2002-01-01

    A metal surface is chromatized with a chromic acid solution to obtain a good adherence of polymer coatings. In this process Cr(VI) is reduced to Cr(III). The oxidation strength of the solution decreases during use. The chrome solution needs to be regenerated and purified. A new anode material,

  13. Novel Chemical Process for Producing Chrome Coated Metal

    OpenAIRE

    Pelar, Christopher; Greenaway, Karima; Zea, Hugo; Wu, Chun-Hsien; Luhrs, Claudia C.; Phillips, Jonathan

    2018-01-01

    The article of record as published may be found at http://dx.doi.org/10.3390/ma11010078 This work demonstrates that a version of the Reduction Expansion Synthesis (RES) process, Cr-RES, can create a micron scale Cr coating on an iron wire. The process involves three steps. I. A paste consisting of a physical mix of urea, chrome nitrate or chrome oxide, and water is prepared. II. An iron wire is coated by dipping. III. The coated, and dried, wire is heated to ~800 ◦C for 10 min in a tube fu...

  14. MICROWAVE MEASUREMENT OF REFRACTORY MATERIALS AT HIGH-TEMPERATURE

    International Nuclear Information System (INIS)

    Kharkovsky, S.; Zoughi, R.; Smith, J.; Davis, B.; Limmer, R.

    2009-01-01

    Knowledge of the electrical behavior of refractory materials may enable the development and optimization of microwave nondestructive techniques to detect and evaluate changes in their physical properties while the materials are in service. This paper presents the results of a limited and preliminary investigation in which two refractory materials (dense chrome and dense zircon) were subjected to increasing temperature in a furnace and in which a frequency-modulated continuous-wave radar operating in the frequency range of 8-18 GHz radar was used to evaluate their attenuation properties.

  15. Microwave Measurement of Refractory Materials at High-Temperature

    Science.gov (United States)

    Kharkovsky, S.; Zoughi, R.; Smith, J.; Davis, B.; Limmer, R.

    2009-03-01

    Knowledge of the electrical behavior of refractory materials may enable the development and optimization of microwave nondestructive techniques to detect and evaluate changes in their physical properties while the materials are in service. This paper presents the results of a limited and preliminary investigation in which two refractory materials (dense chrome and dense zircon) were subjected to increasing temperature in a furnace and in which a frequency-modulated continuous-wave radar operating in the frequency range of 8-18 GHz radar was used to evaluate their attenuation properties.

  16. Structure-phase composition and nano hardness of chrome-fullerite-chrome films irradiated by boron ions

    International Nuclear Information System (INIS)

    Baran, L.V.

    2015-01-01

    By methods of atomic force microscopy, X-ray diffraction and nano indentation the research of change of structure phase composition and nano hardness of the chrome - fullerite - chrome films, subjected to implantation by B + ions (E = 80 keV, F = 5*10 17 ions/cm 2 ) are submitted. It is established, that as a result of Boron ion implantation of the chrome - fullerite - chrome films, chrome and fullerite inter fusion on sues, that is the solid-phase interaction and as a result of which forms the heterophase with increased nano hardness. (authors)

  17. Photo-oxidation. Of the system chrome hexavalent-4-chlorophenol

    International Nuclear Information System (INIS)

    Gil Pavas, Edison; Cabrera Limpias, Marianela; Jaramillo Jimenez, Sergio Alejandro

    2003-01-01

    As a proposal to eliminate highly toxic chemical components derived from industrial waste, the researchers study the behavior of the compound hexavalent chromium / 4-chlorophenol system when subjected to photo degradation in a photo-reactor compound parabolic cylinder (CPC) to scale pilot. The effect is analyzed in order to determine the operation conditions to reach the highest degradation levels possible. The analyzed variables were pH, concentration of catalyst (TiO 2 ), time of recirculation and the relation of initial concentrations among polluting agents. The factor that most influences the levels of removal reached is the pH, which has a different effect for each of the pollutants. This implies that, theoretically, you cannot adopt a unique group of operation parameters to favor the degradation of both however, in the practice; high levels of degradation of both pollutants are obtained in the optimal point of operation of the chrome. It is also observed that the catalyst concentration does not influence the degradation of the polluting agents significantly, at least for the initial concentrations studied. The recirculation time is closely related to the kinetics of degradation of each polluting agent. Elevated degradation levels are reached in a short time for 4-chlorophenol, while more prolonged recirculation times are required for hexavalent chromium. The relation of initial concentrations of the polluting agents also exerts an opposite effect on the degradation levels reached for each polluting agent; the hexavalent chromium reduction is favored with high initial concentrations of 4-chlorophenol, whereas the oxidation of 4-chlorophenol is favored with high initial hexavalent chromium concentrations, which suggests some synergy between the oxidation-reduction reactions of 4-chlorophenol and hexavalent chromium. Finally, a 97% hexavalent chromium reduction and a 94.9% oxidation of 4-chlorophenol were obtained

  18. Study on the efficiency of ceramic coating for avoiding oxidation in carbon refractories

    International Nuclear Information System (INIS)

    Santos, I.M.G.; Cruz Junior, F.; Paskocimas, C.A.; Leite, E.R.; Longo, Elson; Varela, J.A.

    1997-01-01

    A ceramic coating made of sodium phosphossilicate and clay was developed to the protection of refractories against carbon oxidation during the pre-heating of siderurgical equipment. This search has the objective of comparing the refractory behaviour with and without coating, according to temperature, time and atmosphere. The results show that the coating is more efficient at higher temperatures. An important point is that the efficiency is smaller after long thermal is that the efficiency is smaller after long thermal treatments and at very aggressive conditions. In spite of this the oxidation is still smaller than in refractory without coating. (author)

  19. Treatment of refractory organic pollutants in industrial wastewater by wet air oxidation

    Directory of Open Access Journals (Sweden)

    Mingming Luan

    2017-02-01

    Full Text Available Wet air oxidation (WAO is one of the most economical and environmentally-friendly advanced oxidation processes. It makes a promising technology for the treatment of refractory organic pollutants in industrial wastewaters. In wet air oxidation aqueous waste is oxidized in the liquid phase at high temperatures (125–320 °C and pressures (0.5–20 MPa in the presence of an oxygen-containing gas (usually air. The advantages of the process include low operating costs and minimal air pollution discharges. The present review is concerned about the literature published in the treatment of refractory organic pollutants in industrial wastewaters, such as dyes. Phenolics were taken as model pollutants in most cases. Reports on effect of treatment for the WAO of refractory organic pollutants in industrial wastewaters are reviewed, such as emulsified wastewater, TNT red water, etc. Discussions are also made on the mechanism and kinetics of WAO and main technical parameters influencing WAO. Finally, development direction of WAO is summed up.

  20. Application of metal oxide refractories for melting and casting reactive metals

    International Nuclear Information System (INIS)

    Jessen, N.C. Jr.; Holcombe, C.E. Jr.; Townsend, A.B.

    1979-01-01

    Extensive investigations have been conducted to develop metal oxide refractories for containment of molten uranium and uranium alloys. Since uranium and uranium alloys are readily susceptable to the formation of complex oxides, carbides, nitrides, intermetallic compounds, and suboxide reactions, severe problems exist for the production of quality castings. These contamination reactions are dependent on temperature, pressure, and molten metal interfacial reactions. The need for high purity metals to meet specification repeatedly has resulted in the development of improved metal oxide refractories and sophisticated furnace controls. Applications of Y 2 O 3 for use as a crucible and mold coating, precision molds and cores, and high temperature castable ceramics are discussed. Experimental results on melt impurity levels, thermal controls during melting, surface interactions and casting quality are presented

  1. The rise of Chrome

    Directory of Open Access Journals (Sweden)

    Jonathan Tamary

    2015-10-01

    Full Text Available Since Chrome’s initial release in 2008 it has grown in market share, and now controls roughly half of the desktop browsers market. In contrast with Internet Explorer, the previous dominant browser, this was not achieved by marketing practices such as bundling the browser with a pre-loaded operating system. This raises the question of how Chrome achieved this remarkable feat, while other browsers such as Firefox and Opera were left behind. We show that both the performance of Chrome and its conformance with relevant standards are typically better than those of the two main contending browsers, Internet Explorer and Firefox. In addition, based on a survey of the importance of 25 major features, Chrome product managers seem to have made somewhat better decisions in selecting where to put effort. Thus the rise of Chrome is consistent with technical superiority over the competition.

  2. Chrome recycling from leather solid wastes

    International Nuclear Information System (INIS)

    Mohamed, O.A.; Mohamady, H.S.; El-Sayed, N.H.

    2005-01-01

    Leather processing is one of the industrial activities that generate chromium bearing wastes in different forms, one of them is chrome shavings which contributes about 10% of the quantum raw skins /hides, and causes on burning dangerous human hazardous. Hydrolysis processes by different alkalis such as (LiOK KOH, NaOH) have been applied to recover chrome from solid wastes. The extent of hydrolysis was studied as a function of alkalis concentrations, in presence and absence of reducing agents, shaking time and temperature. Hydrolysis process exhibits 99%, 98% and 97%, chrome recovery for LiOH, KOH and NaOH respectively. The recovered chrome has been used in retaining process, examined through visual and mechanical tests of leather samples. The evaluation of the tanning process with recovered chrome gave acceptable results

  3. Total control of chromium in tanneries - thermal decomposition of filtration cake from enzymatic hydrolysis of chrome shavings.

    Science.gov (United States)

    Kocurek, P; Kolomazník, K; Bařinová, M; Hendrych, J

    2017-04-01

    This paper deals with the problem of chromium recovery from chrome-tanned waste and thus with reducing the environmental impact of the leather industry. Chrome-tanned waste was transformed by alkaline enzymatic hydrolysis promoted by magnesium oxide into practically chromium-free, commercially applicable collagen hydrolysate and filtration cake containing a high portion of chromium. The crude and magnesium-deprived chromium cakes were subjected to a process of thermal decomposition at 650°C under oxygen-free conditions to reduce the amount of this waste and to study the effect of magnesium removal on the resulting products. Oxygen-free conditions were applied in order to prevent the oxidation of trivalent chromium into the hazardous hexavalent form. Thermal decomposition products from both crude and magnesium-deprived chrome cakes were characterized by high chromium content over 50%, which occurred as eskolaite (Cr 2 O 3 ) and magnesiochromite (MgCr 2 O 4 ) crystal phases, respectively. Thermal decomposition decreased the amount of chrome cake dry feed by 90%. Based on the performed experiments, a scheme for the total control of chromium in the leather industry was designed.

  4. Thermal spray coatings replace hard chrome

    International Nuclear Information System (INIS)

    Schroeder, M.; Unger, R.

    1997-01-01

    Hard chrome plating provides good wear and erosion resistance, as well as good corrosion protection and fine surface finishes. Until a few years ago, it could also be applied at a reasonable cost. However, because of the many environmental and financial sanctions that have been imposed on the process over the past several years, cost has been on a consistent upward trend, and is projected to continue to escalate. Therefore, it is very important to find a coating or a process that offers the same characteristics as hard chrome plating, but without the consequent risks. This article lists the benefits and limitations of hard chrome plating, and describes the performance of two thermal spray coatings (tungsten carbide and chromium carbide) that compared favorably with hard chrome plating in a series of tests. It also lists three criteria to determine whether plasma spray or hard chrome plating should be selected

  5. Chrome tannage using high-intensity ultrasonic field.

    Science.gov (United States)

    Mäntysalo, E; Marjoniemi, M; Kilpeläinen, M

    1997-04-01

    The process time in chrome tannage in leather making, using an elastic compression cycle followed by irradiation by high-intensity ultrasound, is quite short lasting only a few minutes, compared with a process time of several hours in modern chrome tannage. After ultrasonic irradiation, samples were basified in 17 h in chrome liquor at a pH of 4.0 and the shrinkage temperature was measured. The determination of the efficiency for the chrome liquor penetrating into the hides can be based on the steepness of the shrinkage temperature-processing time curve. An approximate value of 20 degrees C min(-1) can be evaluated for the initial slope of the curve when elastic compression and high-intensity ultrasonic irradiation is used, and a processing time of 2 min is required in chrome liquor (plus 17 h basification and 24 h storage time) to obtain leather stable to boiling. Usually, hides are kept in chrome liquor for 2 h.

  6. Emission during the firing of chrome-magnesite products in tunnel kilns

    Energy Technology Data Exchange (ETDEWEB)

    Krechin, Yu.V.; Telegin, S.V.; Ivanov, N.M.; Kasimov, A.M.; Plichko, E.P.; Sverkov, Yu.M.; Maksimov, B.N.

    1986-11-01

    When chrome-magnesite products are fired in tunnel furnaces, the concentration in the effluent gas of dust is 110-150; of Cr/sub 7/O/sub 3/, 5-7; NO/sub x/, 20-35; CO, 100-125; SO/sub 2/, 25-40; and SO/sub 3/, 30-70 mg/m/sup 3/. The emission dust is finely dispersed. The average size of the particles of dust is 0.3, the minimum 0.05, and the maximum 1 ..mu..m. There is no hydrogen sulfide, NO/sub 2/, or CrO/sub 3/ in the emission. Dust and nitrogen oxides are formed in the firing zone of the kiln. The formation of dust and NO/sub 2/ depends on the air-consumption coefficient. The use of the pipe-in-pipe type of ports does not provide good gas combustion. To improve the operation of the kiln and the combustion of the natural gas it is recommended that instead of the obsolescent tube-in-tube ports, the ports developed by the Eastern Institute of Refractories be installed since they have given good results in tests. To improve the scattering effect of the removal of dust in the existing equipment it is recommended that the height of the flue stacks be increased to 40-50 m.

  7. A study on the utilization of chromic oxide wastes

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seung Woong; Kim, Chi Kwon; Hwang, Seon Kook; Kim, Byung Gyu; Son, Jeong Soo; Nam, Chul Woo [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-01

    This study was carried out to develop the optimum process for recovering precious and valuable metals from chrome oxide wastes. The following subjects such as, (1) feasibility on the recovery of precious and valuable metals, (2) recovery rate of precious and valuable metals, (3) purification of extracted precious and valuable metals, and (4) environmental aspects of recovery process, were investigated and the main results are as follows. (1) With Sem analysis of chrome oxide wastes, it was found that combustion process for eliminating oil and water in wastes, was necessary. (2) After leaching chrome oxide wastes with nitric acid and aqua regia, silver and gold were effectively separated and recovered. But a lot of silver and gold were remaining in the leaching residue. It was considered that chrome oxide powder was coated with organic materials during polishing stage and their products were insoluble in acidic solution. (3) The optimum process for separation and recovery of precious metal and production of new chrome oxide is consist of several process such as perchloric acid leaching, recovery of silver chloride, cementation for gold, reduction of chrome ion, and production of pure chrome oxide. (4) For separating chrome compound from the chrome oxide waste occurred in stainless steel polishing process, alkali roasting process was suggested. (author). 18 refs., 29 figs., 11 tabs.

  8. Lung cancer in Yorkshire chrome platers, 1972-97.

    Science.gov (United States)

    Sorahan, T; Harrington, J M

    2000-06-01

    To investigate mortality from lung cancer in chrome platers, a group exposed to chromic acid. The mortality of a cohort of 1087 chrome platers (920 men, 167 women) from 54 plants situated in the West Riding of Yorkshire, United Kingdom, was investigated for the period 1972-97. All subjects were employed as chrome platers for >/=3 months and all were alive on 31 May 1972. Mortality data were also available for a cohort of 1163 comparison workers with no known occupational exposure to chrome compounds (989 men, 174 women). Information on duration of chrome work and smoking habits collected for a cross sectional survey carried out in 1969-72 were available for 916 (84.3%) of the chrome platers; smoking habits were available for 1004 (86.3%) comparison workers. Two analytical approaches were used, indirect standardisation and Poisson regression. Based on serial mortality rates for the general population of England and Wales, significantly increased mortality from lung cancer was observed (obs) in male chrome platers (obs 60, expected (exp) 32.5, standardised mortality ratio (SMR) 185, pchrome, although data on working after 1972 were not available. Confident interpretation is not possible but occupational exposures to hexavalent chromium may well have been involved in the increased mortality from lung cancer found in this cohort of chrome platers.

  9. The rise of Chrome

    OpenAIRE

    Jonathan Tamary; Dror G. Feitelson

    2015-01-01

    Since Chrome’s initial release in 2008 it has grown in market share, and now controls roughly half of the desktop browsers market. In contrast with Internet Explorer, the previous dominant browser, this was not achieved by marketing practices such as bundling the browser with a pre-loaded operating system. This raises the question of how Chrome achieved this remarkable feat, while other browsers such as Firefox and Opera were left behind. We show that both the performance of Chrome and its co...

  10. Refinement in black chrome for use as a solar selective coating

    Science.gov (United States)

    Mcdonald, G. E.

    1974-01-01

    Black chrome is significant as a solar selective coating because the current extensive use of black chrome in the electroplating industry as a durable decorative finish makes black chrome widely available on a commercial scale and potentially low in cost as a solar selective coating. Black-chrome deposits were modified by underplating with dull nickel or by being plated on rough surfaces. Both of these procedures increased the visible absorptance. There was no change in the infrared reflectance for the dull-nickel - black-chrome combination from that reported for the bright-nickel - black-chrome combination. However, the bright-nickel - black-chrome coating plated on rough surfaces indicated a slight decrease in infrared reflectance. As integrated over the solar spectrum for air mass 2, the reflectance of the dull-nickel - black-chrome coating was 0.077, of the bright-nickel - black-chrome coating plated on a 0.75-micron (30-microinch) surface was 0.070, of the bright-nickel - black-chrome coating plated on a 2.5 micron (100-microinch) surface was 0.064. The corresponding values for the bright-nickel - black-chrome coating on a 0.0125-micron (0.5-microinch) surface, two samples of black nickel, and two samples of Nextrel black paint were 0.132, 0.123, 0.133, and 0.033, respectively.

  11. Development of CMOS MEMS inductive type tactile sensor with the integration of chrome steel ball force interface

    Science.gov (United States)

    Yeh, Sheng-Kai; Chang, Heng-Chung; Fang, Weileun

    2018-04-01

    This study presents an inductive tactile sensor with a chrome steel ball sensing interface based on the commercially available standard complementary metal-oxide-semiconductor (CMOS) process (the TSMC 0.18 µm 1P6M CMOS process). The tactile senor has a deformable polymer layer as the spring of the device and no fragile suspended thin film structures are required. As a tactile force is applied on the chrome steel ball, the polymer would deform. The distance between the chrome steel ball and the sensing coil would changed. Thus, the tactile force can be detected by the inductance change of the sensing coil. In short, the chrome steel ball acts as a tactile bump as well as the sensing interface. Experimental results show that the proposed inductive tactile sensor has a sensing range of 0-1.4 N with a sensitivity of 9.22(%/N) and nonlinearity of 2%. Preliminary wireless sensing test is also demonstrated. Moreover, the influence of the process and material issues on the sensor performances have also been investigated.

  12. Don’t let Chrome expose your passwords

    CERN Multimedia

    Computer Security Team

    2013-01-01

    Do you still struggle with remembering your password? Is this despite our many attempts to help you: “Train your Brain: Don't put your password on paper!" (article here), “Creativity@CERN” (article here) and “Maths to the rescue!" (article here)? Then you might have considered the “save your password” features in Chrome, Firefox or Internet Explorer… these features remember your Facebook, CERN, Twitter, Amazon and ebay passwords. But be careful: it might be easy for someone to read them!   If enabled, Chrome, Firefox, Internet Explorer and others can remember the password of specific sites after you’ve logged in to those sites the first time. As the passwords are, however, stored in plain text, they can still be read out by anyone with access to that computer. In Chrome, just type “chrome://settings/passwords” and click the password you want to reveal. Or in F...

  13. ELABORATION PROCESS OF REFRACTORY MATERIALS BY REACTIVE PROJECTION OF OXIDE, PEROXIDE AND METALS

    OpenAIRE

    Pilatti , M.; Cransveld , J.; Raymond , G.; Plumat , E.; Duvigneaud , P.

    1986-01-01

    A device has been set up for spraying with accuracy a compound having a controlled grain size of refractory oxide, peroxide and metals. The refractory material is obtained by melting and recristallisation on a preheated substrate. Composition in the CaO.Al2O3 system and in the CaO-Al2O3-ZrO2 system have been synthesized. They have been analysed by X-ray diffraction and SEM. Dense and well cristallized materials have been deposited. This process can be successfully applied for the repair of a ...

  14. Ultrasound assisted chrome tanning: Towards a clean leather production technology.

    Science.gov (United States)

    Mengistie, Embialle; Smets, Ilse; Van Gerven, Tom

    2016-09-01

    Nowadays, there is a growing demand for a cleaner, but still effective alternative for production processes like in the leather industry. Ultrasound (US) assisted processing of leather might be promising in this sense. In the present paper, the use of US in the conventional chrome tanning process has been studied at different pH, temperature, tanning time, chrome dose and US exposure time by exposing the skin before tanning and during tanning operation. Both prior exposure of the skin to US and US during tanning improves the chrome uptake and reduces the shrinkage significantly. Prior exposure of the skin to US increase the chrome uptake by 13.8% or reduces the chrome dose from 8% to 5% (% based on skin weight) and shorten the process time by half while US during tanning increases the chrome uptake by 28.5% or reduces the chrome dose from 8% to 4% (half) and the tanning time to one third compared to the control without US. Concomitantly, the resulting leather quality (measured as skin shrinkage) improved from 5.2% to 3.2% shrinkage in the skin exposed to US prior tanning and to 1.3% in the skin exposed to US during the tanning experiment. This study confirms that US chrome tanning is an effective and eco-friendly tanning process which can produce a better quality leather product in a shorter process time with a lower chromium dose. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Lung cancer in Yorkshire chrome platers, 1972-97

    OpenAIRE

    Sorahan, T.; Harrington, J

    2000-01-01

    OBJECTIVES—To investigate mortality from lung cancer in chrome platers, a group exposed to chromic acid.
METHODS—The mortality of a cohort of 1087 chrome platers (920 men, 167 women) from 54 plants situated in the West Riding of Yorkshire, United Kingdom, was investigated for the period 1972-97. All subjects were employed as chrome platers for ⩾3 months and all were alive on 31 May 1972. Mortality data were also available for a cohort of 1163 comparison workers with no known occupational expo...

  16. Hex Chrome Free Coatings for Electronics Overview

    Science.gov (United States)

    Kessel, Kurt

    2013-01-01

    The overall objective of the Hex Chrome Free Coatings for Electronics project is to evaluate and test pretreatment coating systems not containing hexavalent chrome in avionics and electronics housing applications. This objective will be accomplished by testing strong performing coating systems from prior NASA and DoD testing or new coating systems as determined by the stakeholders.

  17. Crack resistance of tungsten strengthened by dispersed refractory oxides

    International Nuclear Information System (INIS)

    Babak, A.V.; Uskov, E.I.

    1984-01-01

    Investigation results are presented for crack resistance of commercial tungsten, obtained during specimen testing at temperatures of 20 deg C to Tsub(cr) (upper boundary of temperature range of ductile-brittle transition). Comparison of s-n diagrams and temperature dependences of crack resistance are conducted for commercial tungsten and tungsten strengthened by refractory oxides. It is shown that dispersion hardening increases crack resistance in the temperature range of 20 to 2000 deg C but the upper boundary of ductile-brittle shifts to the side of higher temperatures

  18. LABORATORY STUDY FOR THE REDUCTION OF CHROME (VI) TO CHROME (III) USING SODIUM METABISULFITE UNDER ACIDIC CONDITIONS

    International Nuclear Information System (INIS)

    DUNCAM JB; GUTHRIE MD; LUECK KJ; AVILA M

    2007-01-01

    This report describes the results from RPP-PLAN-32738, 'Test Plan for the Effluent Treatment Facility to Reduce Chrome(VI) to Chrome(I1I) in the Secondary Waste Stream', using sodium metabisulfite. Appendix A presents the report as submitted by the Center for Laboratory Sciences (CLS) to CH2M HILL Hanford Group, Inc. The CLS carried out the laboratory effort under Contract Number 21065, release Number 30. This report extracts the more pertinent aspects of the laboratory effort

  19. LABORATORY STUDY FOR THE REDUCTION OF CHROME (VI) TO CHROME (III) USING SODIUM METABISULFITE UNDER ACIDIC CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAM JB; GUTHRIE MD; LUECK KJ; AVILA M

    2007-07-18

    This report describes the results from RPP-PLAN-32738, 'Test Plan for the Effluent Treatment Facility to Reduce Chrome(VI) to Chrome(I1I) in the Secondary Waste Stream', using sodium metabisulfite. Appendix A presents the report as submitted by the Center for Laboratory Sciences (CLS) to CH2M HILL Hanford Group, Inc. The CLS carried out the laboratory effort under Contract Number 21065, release Number 30. This report extracts the more pertinent aspects of the laboratory effort.

  20. Improvements in or relating to refractory oxide protective coatings for fuel can

    International Nuclear Information System (INIS)

    Cairns, J.A.; Bennett, M.J.; Linacre, J.K.

    1981-01-01

    An improved coating for Advanced Gas Cooled Nuclear Reactor austenitic stainless steel fuel cans is described which, tests have shown, inhibits the deposition of carbon on the cans in carbon-containing ionising radiation environments. The coating comprises a refractory oxide which has been prepared by a vapour phase condensation method, in combination with a noble metal. (U.K.)

  1. Chrome-free Samarium-based Protective Coatings for Magnesium Alloys

    Science.gov (United States)

    Hou, Legan; Cui, Xiufang; Yang, Yuyun; Lin, Lili; Xiao, Qiang; Jin, Guo

    The microstructure of chrome-free samarium-based conversion coating on magnesium alloy was investigated and the corrosion resistance was evaluated as well. The micro-morphology, transverse section, crystal structure and composition of the coating were observed by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and X- ray photoelectron spectroscopy (XPS), respectively. The corrosion resistance was evaluated by potentiodynamic polarization curve and electrochemical impedance spectroscopy (EIS). The results reveal that the morphology of samarium conversion coating is of crack-mud structure. Tiny cracks distribute in the compact coating deposited by samarium oxides. XRD, EDS and XPS results characterize that the coating is made of amorphous and trivalent-samarium oxides. The potentiodynamic polarization curve, EIS and OCP indicate that the samarium conversion coating can improve the corrosion resistance of magnesium alloys.

  2. Investigation of the structure of nanocrystalline refractory oxides by X-ray diffraction, electron microscopy, and atomic force microscopy

    International Nuclear Information System (INIS)

    Ulyanova, T. M.; Titova, L. V.; Medichenko, S. V.; Zonov, Yu. G.; Konstantinova, T. E.; Glazunova, V. A.; Doroshkevich, A. S.; Kuznetsova, T. A.

    2006-01-01

    The structures of nanocrystalline fibrous powders of refractory oxides have been investigated by different methods: determination of coherent-scattering regions, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic-force microscopy (AFM). The sizes of nanograins of different crystalline phases of refractory metal oxides have been determined during the formation of these nanograins and the dynamics of their growth during heat treatment in the temperature range 600-1600 deg. C has been studied. The data on the structure of nanocrystalline refractory oxide powders, obtained by different methods, are in good agreement. According to the data on coherent-scattering regions, the sizes of the ZrO 2 (Y 2 O 3 ) and Al 2 O 3 grains formed are in the range 4-6 nm, and the particle sizes determined according to the TEM and AFM data are in the ranges 5-7 and 2-10 nm, respectively. SEM analysis made it possible to investigate the dynamics of nanoparticle growth at temperatures above 1000 deg. C and establish the limiting temperatures of their consolidation in fibers

  3. Waste Treatment of Chrome Residue of Chromium Recovery Process Using Calcium Carbonate

    International Nuclear Information System (INIS)

    Endro Kismolo; Prayitno; Nurimaniwathy

    2002-01-01

    The aim of the research was to apply the precipitation technology for the treatment of aqueous wastes of leather tanning industries. The chrome liquid wastes taken was the effluent from the residue of the chromium recovery process using magnesium oxide. The precipitant used was calcium carbonate. The experiments was performed by adjusting the concentration of calcium carbonate from 50 ppm, 100 ppm, 150 ppm, 200 ppm, 250 ppm, 300 ppm, 350 ppm to 400 ppm. The stirring speed was varied from 50 rpm, 75 rpm, 100 rpm, 125 rpm, 150 rpm, 175 rpm to 200 rpm. The time of mixing was varied from 30 minutes, 60 minutes, 90 minutes, 120 minutes, 150 minutes, 175 minutes and 200 minutes. The result from the experiments lead to the best condition obtained were the concentration of precipitant was 300 ppm, flow rates of mixing was 125 rpm and time of mixing was 60 minutes. At this condition the separations efficiency of chrome obtained was 99.985%. (author)

  4. 40 CFR 415.340 - Applicability; description of the chrome pigments production subcategory.

    Science.gov (United States)

    2010-07-01

    ... chrome pigments production subcategory. 415.340 Section 415.340 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Chrome Pigments Production Subcategory § 415.340 Applicability; description of the chrome pigments production subcategory. This subpart applies to discharges to waters of the United States and...

  5. High exhaust chrome complex using chrome tanned tannery, solid wastes and common hydrocarbons as reductants and masking agents to minimize the liquid and solid wastes: tanning and environmental impact studies

    International Nuclear Information System (INIS)

    Nawaz, H.R.

    2005-01-01

    Still no alternate of chrome tanning has been found to achieve the best quality and quantity of leather. But the chrome tanning process is associated with the generation of very toxic liquid and solid wastes. Therefore we emphasized to develop an efficient process for the synthesis of high exhaust chrome complex that could minimize the both liquid and solid wastes up to very low limit. In this research, chrome shavings and raw organic compounds have beneficially utilized as a reductant as well as potential masking agents providing a comprehensive close loop. Two chrome tanning materials have been developed using leather shavings with molasses in product A and replacement of molasses by other organic compounds for chrome complex B. These materials have also been employed for the tanning of goatskins parallel to the commercial BCS from the market. The comparative studies revealed that, the quality of leather made from product B is either better or comparable with the conventional tanning material. The chrome contents in leather have been increased with the simultaneous decreased in spent chrome liquor. Hence the exhaustion rate of chrome complex B has been noted up to 95%. While the physical characteristics of resulted leather from product A and B have been found comparable to that of conventional tanned leather. Therefore this methodology would not only reduce liquid and solid wastes but also provide quality leather and economically multi benefits. (author)

  6. The coating layer structure of commercial chrome plates

    International Nuclear Information System (INIS)

    Chen, Sheng

    2015-01-01

    Highlights: • AES and XPS depth profiling analysis were used in the experiment. • The detailed coating layer structure of the commercial chrome plate was obtained. • Peak fitting method was used to investigate the chemical states of Cr in the coating. - Abstract: The surface and cross-sectional morphologies of the commercial chrome plate coating layer with the thickness of dozens of nanometers have been observed. To investigate the detailed structure of the coating layer, Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) combined with the low energy Ar + sputtering technique have been employed. Through careful analysis of experimental data, it can be obtained that the coating layer of commercial chrome plates is composed of four layers from top to bottom with different compositions

  7. Gold recovery from refractory ores. The role of pressure oxidation. Recuperacion de oro de minerales refractarios. El papel de la oxidacion a presion

    Energy Technology Data Exchange (ETDEWEB)

    Alguacil, F.J.; Cobo, A.; Caravaca, C. (Consejo Superior de Investigaciones Cientificas. Centro Nacional de Investigaciones Metalurgicas. Madrid (Spain))

    1993-01-01

    Pressure oxidation is a hydrometallurgical technique that renders auriferous refractory materials, specially sulphides, amenable to cyanidation process. The effectiveness of the operation as a pretreatment to the recovery of refractory gold, is reflected by the succesful startup over the last ten years of seven commercial plants. Some factors affecting the selection of pressure oxidation as pretreatment for gold recovery are discussed. (Author)

  8. A novel electrochemical sensor for the analysis of β-agonists: The poly(acid chrome blue K)/graphene oxide-nafion/glassy carbon electrode

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Xiaoyun [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047 (China); Ni, Yongnian, E-mail: ynni@ncu.edu.cn [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047 (China); Department of Chemistry, Nanchang University, Nanchang 330031 (China); Kokot, Serge, E-mail: s.kokot@qut.edu.au [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane 4001 (Australia)

    2013-09-15

    Graphical abstract: A new modified electrode was constructed by the electro-polymerization of acid chrome blue K (ACBK) at a graphene-nafion modified glassy carbon electrode (GCE). The novel electrode was successfully employed for the analysis of eight β-agonist analytes with high sensitivity. -- Highlights: • Construction of the poly-ACBK/graphene-nafion/GCE. •The modified electrode showed high sensitivity for the analysis of the β-agonists. • A novel method was successfully developed for the analysis of clenbuterol in pork. • Research provided a new method of constructing electrodes for biological analysis. -- Abstract: A novel modified electrode was constructed by the electro-polymerization of 4,5-dihydroxy-3-[(2-hydroxy-5-sulfophenyl)azo]-2,7-naphthalenedisulfonic acid trisodium salt (acid chrome blue K (ACBK)) at a graphene oxide (GO)-nafion modified glassy carbon electrode (GCE). The characterization of an electrochemically synthesized poly-ACBK/GO-nafion film was investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), atomic force microscopy (AFM) and scanning electron microscopy (SEM) techniques, and the results were interpreted and compared at each stage of the electrode construction. Electrochemical oxidation of eight β-agonists – clenbuterol, salbutamol, terbutaline, ractopamine, dopamine, dobutamine, adrenaline, and isoprenaline, was investigated by CV at the different electrodes. At the poly-ACBK/GO-nafion/GCE, the linear sweep voltammetry peak currents of the eight β-agonists increased linearly with their concentrations in the range of 1.0–36.0 ng mL{sup −1}, respectively, and their corresponding limits of detection (LODs) were within the 0.58–1.46 ng mL{sup −1} range. This electrode showed satisfactory reproducibility and stability, and was used successfully for the quantitative analysis of clenbuterol in pork samples.

  9. LEACHABILITY OF CHROME FROM MAGNESIA-CHROMITE REFRACTORY BRICKS CORRODED BY Cu/CuO- Na2O.2SiO2 SLAGS

    Directory of Open Access Journals (Sweden)

    David Medved

    2015-06-01

    Full Text Available The interactions of magnesia-chromite refractory brick with Cu-Na2O.2SiO2 and CuO-Na2O.2SiO2 melts are studied and the chemical durability of corrosion products in water is evaluated. The corrosion tests confirm intensive infiltration of the slag melts into the tested refractory bricks and formation of Cr(6+ compounds. The molten copper partially oxidizes during corrosion test by air and penetrates into bricks. Interactions among periclase (MgO and chromite (FeCr2O4 grains with the melt Na2O.2SiO2 and copper oxides makes possible to form several compounds (e.g. Cu2MgO3, CuCrO4, CaCrO4, Na2CrO4, MgCrO4. Just the marked yellow spots, which were observed on the corroded brick surface after 30 days of free storage, suggest hydration of the high-temperature corrosion products. The yellow color of spots points out to chromates as Na2CrO4 and MgCrO4, which are well soluble in water. The leaching of corroded bricks in water (batch leaching test of a ratio of S (solid : W (water = 0.1 taking up to 28 days confirmed the Cr, Na, Mg and Ca ions leach-out. The pH value of solution increased up to 9 during leaching mainly as a consequence of elevated Na+ ion concentration. The Cr ion concentration rises in the solution up to 1 mmol.l-1. The observed moderate decrease of Cr ion concentration in the solution with the length of leaching indicates super-saturation of the solution and precipitation of the products.

  10. Improvement of exhaustion and fixation of chrome tan by hydroxy organic acids

    International Nuclear Information System (INIS)

    Nashy, E.H.A.; Khedr, M.H.; EL-Sayed, N.H.

    2005-01-01

    Chrome tan is the most important tanning agent in the tanning industry, but it causes extreme pollution due to the incomplete exhaustion of the serious chrome cations in tanning bath. The exhaustion and fixation of chrome tan were improved in this study through treatment of delimed hide with three carboxylic acids named citric, malic and tartaric acids before exposure to tanning process. The process was optimized taking into the account the shaking rate, chrome concentration (%), initial ph, acids concentration, and temperature and contact time. The optimum conditions for exhaustion, fixation, shrinkage temperature as well as skin quality showed that agitation rate of 150 rpm, chrome concentration of 16%, initial ph of 8.5, acid concentration of 3% tartaric acid, temperature of 35 degree C and contact time of 24 hr.The best results obtained are 88% exhaustion, 88.32% fixation and 106 degree C shrinkage temperature in aqueous medium

  11. Articulation of Native Cartilage Against Different Femoral Component Materials. Oxidized Zirconium Damages Cartilage Less Than Cobalt-Chrome.

    Science.gov (United States)

    Vanlommel, Jan; De Corte, Ronny; Luyckx, Jean Philippe; Anderson, Melissa; Labey, Luc; Bellemans, Johan

    2017-01-01

    Oxidized zirconium (OxZr) is produced by thermally driven oxidization creating an oxidized surface with the properties of a ceramic at the top of the Zr metal substrate. OxZr is much harder and has a lower coefficient of friction than cobalt-chrome (CoCr), both leading to better wear characteristics. We evaluated and compared damage to the cartilage of porcine patella plugs, articulating against OxZr vs CoCr. Our hypothesis was that, owing to its better wear properties, OxZr would damage cartilage less than CoCr. If this is true, OxZr might be a better material for the femoral component during total knee arthroplasty if the patella is not resurfaced. Twenty-one plugs from porcine patellae were prepared and tested in a reciprocating pin-on-disk machine while lubricated with bovine serum and under a constant load. Three different configurations were tested: cartilage-cartilage as the control group, cartilage-OxZr, and cartilage-CoCr. Macroscopic appearance, cartilage thickness, and the modified Mankin score were evaluated after 400,000 wear cycles. The control group showed statistically significant less damage than plugs articulating against both other materials. Cartilage plugs articulating against OxZr were statistically significantly less damaged than those articulating against CoCr. Although replacing cartilage by an implant always leads to deterioration of the cartilage counterface, OxZr results in less damage than CoCr. The use of OxZr might thus be preferable to CoCr in case of total knee arthroplasty without patella resurfacing. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Molecular spectroscopic study for suggested mechanism of chrome tanned leather

    Science.gov (United States)

    Nashy, Elshahat H. A.; Osman, Osama; Mahmoud, Abdel Aziz; Ibrahim, Medhat

    2012-03-01

    Collagen represents the structural protein of the extracellular matrix, which gives strength of hides and/or skin under tanning process. Chrome tan is the most important tanning agent all over the world. The methods for production of leather evolved over several centuries as art and engineering with little understanding of the underlying science. The present work is devoted to suggest the most probable mechanistic action of chrome tan on hide proteins. First the affect of Cr upon hide protein is indicated by the studied mechanical properties. Then the spectroscopic characterization of the hide protein as well as chrome tanned leather was carried out with Horizontal Attenuated Total Reflection (HATR) FT-IR. The obtained results indicate how the chromium can attached with the active sites of collagen. Molecular modeling confirms that chromium can react with amino as well as carboxylate groups. Four schemes were obtained to describe the possible interactions of chrome tan with hide proteins.

  13. Qualification and Flight Test of Non-Chrome Primers for C-130 Aircraft

    Science.gov (United States)

    2011-08-17

    system  Significant hexavalent chrome reduction in finish system  Potential exposure level of spray applied chromated conversion coating not as...Lockheed Martin Aeronautics Company Qualification and Flight Test of Non- Chrome Primers for C-130 Aircraft Scott Jones Lockheed Martin...00-2011 to 00-00-2011 4. TITLE AND SUBTITLE Qualification and Flight Test of Non- Chrome Primers for C-130 Aircraft 5a. CONTRACT NUMBER 5b. GRANT

  14. Refractory of Furnaces to Reduce Environmental Impact

    International Nuclear Information System (INIS)

    Hanzawa, Shigeru

    2011-01-01

    The energy load of furnaces used in the manufacturing process of ceramics is quite large. Most of the environmental impact of ceramics manufacturing is due to the CO 2 produced from this high energy load. To improve this situation, R and D has focused on furnace systems and techniques of control in order to reduce energy load. Since furnaces are comprised of refractory, consideration of their mechanical and thermal characteristics is important. Herein are described several refractory types which were chosen through comparison of the characteristics which contribute to heat capacity reduction, heat insulating reinforcement and high emissivity, thereby improving thermal radiation heat transfer efficiency to the ceramic articles. One selected refractory material which will reduce the environmental impact of a furnace, chosen considering low heat capacity and high emissivity characteristics, is SiC. In this study, thermal radiation heat transfer efficiency improvement and its effect on ceramic articles in the furnace and oxidation behaviour were investigated at 1700K. A high density SiC refractory, built into the furnace at construction, has relatively high oxidation durability and has the ability to reduce environmental impact-CO 2 by 10 percent by decreasing the furnace's energy load. However, new oxidation prevention techniques for SiC will be necessary for long-term use in industrial furnaces, because passive to active oxidation transition behaviour of commercial SiC refractory is coming to close ideal.

  15. Refractory of Furnaces to Reduce Environmental Impact

    Science.gov (United States)

    Hanzawa, Shigeru

    2011-10-01

    The energy load of furnaces used in the manufacturing process of ceramics is quite large. Most of the environmental impact of ceramics manufacturing is due to the CO2 produced from this high energy load. To improve this situation, R&D has focused on furnace systems and techniques of control in order to reduce energy load. Since furnaces are comprised of refractory, consideration of their mechanical and thermal characteristics is important. Herein are described several refractory types which were chosen through comparison of the characteristics which contribute to heat capacity reduction, heat insulating reinforcement and high emissivity, thereby improving thermal radiation heat transfer efficiency to the ceramic articles. One selected refractory material which will reduce the environmental impact of a furnace, chosen considering low heat capacity and high emissivity characteristics, is SiC. In this study, thermal radiation heat transfer efficiency improvement and its effect on ceramic articles in the furnace and oxidation behaviour were investigated at 1700K. A high density SiC refractory, built into the furnace at construction, has relatively high oxidation durability and has the ability to reduce environmental impact-CO2 by 10 percent by decreasing the furnace's energy load. However, new oxidation prevention techniques for SiC will be necessary for long-term use in industrial furnaces, because passive to active oxidation transition behaviour of commercial SiC refractory is coming to close ideal.

  16. Preparation and properties of crystals of mixed refractory oxides with perovskite structure

    Energy Technology Data Exchange (ETDEWEB)

    Melekh, B T; Andreev, A A; Kartenko, N F; Pevtsov, A B; Trepakov, V A; Filin, Yu N [AN SSSR, Moscow. Fiziko-Tekhnicheskij Inst.

    1982-10-01

    Peculiar features of crystal growth of some complex refractory oxides with perovskite structure using the method of direct high-frequency melting in a cold container are studied. Melting, synthesis and directed crystallization have been conducted in the air. X-ray diffraction investigations of the prepared SrTiO/sub 3/, CaZrO/sub 3/, BaZrO/sub 3/, BaHFO/sub 3/, LaCrO/sub 3/, YCrO/sub 3/, ErCrO/sub 3/, La/sub 2/Ti/sub 2/O/sub 7/, LaTaO/sub 3/ and other oxides are conducted, lattice parameters are given. Optical spectra of absorption, photo- and thermoluminescence and thermostimulated currents are studied.

  17. Production of crystalline refractory metal oxides containing colloidal metal precipitates and useful as solar-effective absorbers

    Science.gov (United States)

    Narayan, Jagdish; Chen, Yok

    1983-01-01

    This invention is a new process for producing refractory crystalline oxides having improved or unusual properties. The process comprises the steps of forming a doped-metal crystal of the oxide; exposing the doped crystal in a bomb to a reducing atmosphere at superatmospheric pressure and a temperature effecting precipitation of the dopant metal in the crystal lattice of the oxide but insufficient to effect net diffusion of the metal out of the lattice; and then cooling the crystal. Preferably, the cooling step is effected by quenching. The process forms colloidal precipitates of the metal in the oxide lattice. The process may be used, for example, to produce thermally stable black MgO crystalline bodies containing magnetic colloidal precipitates consisting of about 99% Ni. The Ni-containing bodies are solar-selective absorbers, having a room-temperature absorptivity of about 0.96 over virtually all of the solar-energy spectrum and exhibiting an absorption edge in the region of 2 .mu.m. The process parameters can be varied to control the average size of the precipitates. The process can produce a black MgO crystalline body containing colloidal Ni precipitates, some of which have the face-centered-cubic structure and others of which have the body-centered cubic structure. The products of the process are metal-precipitate-containing refractory crystalline oxides which have improved or unique optical, mechanical, magnetic, and/or electronic properties.

  18. Hexavalent Chrome Free Coatings for Electronics: Electromagnetic Interference (EMI) Shielding Effectiveness (SE)

    Science.gov (United States)

    Kessel, Kurt R.

    2016-01-01

    Determine the suitability of trivalent chromium conversion coatings that meet the requirements of MIL-DTL-5541, Type II, for use in applications where high-frequency electrical performance is important. Evaluate the ability of hexavalent chrome free pretreated aluminum to form adequate EMI seals, and maintain that seal while being subjected to harsh environmental conditions. Assess the performance of trivalent chromium pretreatments against a known control hexavalent chrome pretreatment before and after they have been exposed to a set of environmental conditions. It is known that environmental testing causes a decrease in shielding effectiveness when hexavalent chrome pretreatments are used (Alodine 1200s). Need to determine how shielding effectiveness will be affected with the use of hexavalent chrome free pretreatments. Performance will be assessed by evaluating shielding effectiveness (SE) test data from a variety of test samples comprised of different aluminum types and/or conversion coatings. The formation of corrosion will be evaluated between the mating surfaces and gasket to assess the corrosion resistant properties of the pretreatments, comparing the hexavalent control to the hexavalent chrome free pretreatments.

  19. Hexavalent Chrome Free Coatings for Electronics Applications: Joint Test Report

    Science.gov (United States)

    Rothgeb, Matt; Kessel, Kurt

    2013-01-01

    The overall objective of the Hexavalent Chrome Free Coatings for Electronics Applications project is to evaluate and test pretreatments not containing hexavalent chrome in avionics and electronics housing applications. This objective will be accomplished by testing strong performing coating systems from prior NASA and DoD testing or new coating systems as determined by the stakeholders.

  20. Evaluation of the reusing of MGO-C refractory brick in refractory mixes

    International Nuclear Information System (INIS)

    Silva, R.D.S. da; Braganca, S.R.

    2012-01-01

    The residue from the use of MgO-C refractories in electric arc furnace presents, mostly, magnesium oxide in its composition and some slag contamination and impurities from the process of electrofusion scrap iron/steel. In this study, it was studied the characteristics of this residue and reused through its introduction into a commercial refractory mix, employed as material of coating and repair. This refractory mix was tested by thermogravimetric analysis, compressive strength, evaluation of plasticity and porosity as well as aspects of its installation, such as adhesion in situ. Results showed that there potential for reuse with the introduction of the waste in commercial mix was 30%, with little loss of compressive strength and plasticity. (author)

  1. THE CHROME-TANNED GOAT LEATHER FOR HIGH QUALITY OF BATIK

    Directory of Open Access Journals (Sweden)

    W. Pancapalaga

    2015-09-01

    Full Text Available in which the first stage aimed to evaluate sodium silica as batik wax releasing agent on chrome leather.Completely randomized design (CRD was applied in this study. The concentration of sodium silica wastreated as treatments, in which Tl = 0, T2 = 2 g/L, T3: 4 g/L and T4 = 6 g/L. The second stage of thestudy was aimed to evaluate the type of dye used in batik method dyeing on chrome-tanned goat leather.CRD was used and the treatments were types of dye, i.e. T'1 = acid, T'2= indigosol, T'3 = napthol, T'4 =remazol. In both studies, 9 replicates were applied for each treatment. The use of sodium silicateconcentration of 2 g/L resulted in the percentage of release wax of 91.4% and did not degrade the qualityof chrome leather. The type of acid dyes and naphthol provided the best adhesion and color brightnessand resistance to washing treatment, water, sweat, bend, and rub at 4/5 to 5 on a scale of gray. Inconclusion, chrome tanned goat leather with batik dyeing method was recommended to become one ofthe raw materials of leather goods.

  2. Laboratory studies of refractory metal oxide smokes

    International Nuclear Information System (INIS)

    Nuth, J.A.; Nelson, R.N.; Donn, B.

    1989-01-01

    Studies of the properties of refractory metal oxide smokes condensed from a gas containing various combinations of SiH4, Fe(CO)5, Al(CH3)3, TiCl4, O2 and N2O in a hydrogen carrier stream at 500 K greater than T greater than 1500 K were performed. Ultraviolet, visible and infrared spectra of pure, amorphous SiO(x), FeO(x), AlO(x) and TiO(x) smokes are discussed, as well as the spectra of various co-condensed amorphous oxides, such as FE(x)SiO(y) or Fe(x)AlO(y). Preliminary studies of the changes induced in the infrared spectra of iron-containing oxide smokes by vacuum thermal annealing suggest that such materials become increasingly opaque in the near infrared with increased processing: hydration may have the opposite effect. More work on the processing of these materials is required to confirm such a trend: this work is currently in progress. Preliminary studies of the ultraviolet spectra of amorphous Si2O3 and MgSiO(x) smokes revealed no interesting features in the region from 200 to 300 nm. Studies of the ultraviolet spectra of both amorphous, hydrated and annealed SiO(x), TiO(x), AlO(x) and FeO(x) smokes are currently in progress. Finally, data on the oxygen isotopic composition of the smokes produced in the experiments are presented, which indicate that the oxygen becomes isotopically fractionated during grain condensation. Oxygen in the grains is as much as 3 percent per amu lighter than the oxygen in the original gas stream. The authors are currently conducting experiments to understand the mechanism by which fractionation occurs

  3. Syndeformation Chrome Spinels Inclusions in the Plastically Deformed Olivine Aggregates (Kraka Ophiolites, the Southern Urals

    Directory of Open Access Journals (Sweden)

    D. E. Saveliev

    2015-12-01

    Full Text Available This article presents the results of structural, petrographic, mineralogical and chemical studies of dunite veinlets in spinel peridotite from the Kraka ophiolites. It is demonstrated that plastic deformation of polycrystalline olivine, which form dunite, was accompanied by precipitation of impurities (aluminum and chrome as newly formed chrome spinels. The thinnest acicular inclusions of 0.3-0.5 micron thick are aligned in olivine grains along [010] axis. Bigger elongated irregular chrome spinel grains usually occur along grain and sub-grain olivine boundaries, and, occasionally, inside the grains along [100] axis. Alteration from the fine xenomorphic grains of chrome spinels to the bigger idiomorphic crystals was observed. Analogically to dynamic ageing (dispersion hardening in metals, the structural and chemical alterations in dunites are interpreted as deformation induced segregation of impurities. It is suggested that the euhedral chrome spinel grains typical for ophiolitic dunites were formed by coalescence and spheroidization. This process may be a key factor in the formation of ophiolitic chrome ore deposits.

  4. Electrodeposition of Nanocrystalline Co-P Coatings as a Hard Chrome Alternative (Briefing Charts)

    Science.gov (United States)

    2011-02-10

    chrome plating utilizes chromium in the hexavalent state (Cr6+) Cr6+ is a known carcinogen and poses a health risk to operators OSHA lowered the Cr6+ PEL...from 52 µg/m3 to 5 µg/m3 8 Apr 09, Memorandum, DoD Directive Hexavalent Chromium Management Policy NAVAIR Cr6+ Authorization Process Hard Chrome ...Aerospace & Defense February 10, 2011 Electrodeposition of Nanocrystalline Co-P Coatings as a Hard Chrome Alternative Jack Benfer Co-PI NAVAIR

  5. Chrome-tanned leather shavings as a filler of butadiene-acrylonitrile rubber.

    Science.gov (United States)

    Przepiórkowska, A; Chrońska, K; Zaborski, M

    2007-03-06

    The noxious wastes from the tanning industry such as chrome-tanned leather shavings were used as the only filler of rubber mixes containing carboxylated butadiene-acrylonitrile rubber (XNBR) or butadiene-acrylonitrile rubber (NBR), and a dispersing agent Limanol PEV (Schill & Seilacher). The best form addition of leather powder to the rubber mixes is mixed the waste protein with zinc oxide. The leather powder added to the rubber mixes improves the mechanical properties: tensile strength (T(s)), elongation at break (epsilon(b)) and increase the cross-linking density of carboxylated XNBR and NBR rubber mixes. Satisfactory results of these studies are presented in this work.

  6. Treatment of hexavalent chrome by bacteria. Saikin ni yoru rokka kuromu no shori

    Energy Technology Data Exchange (ETDEWEB)

    Otake, H [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1993-08-01

    A biological reduction method in which hazardous hexavalent chrome is reduced by bacteria is explained as one of the bioremediation technologies. Those bacteria are separated from active sludge in the urban sewage treatment plant. The hexavalent chrome-reducing bacteria were isolated by cultivating the sludge. They were Enterobacter cloacae which are intestinal bacteria. Then, they were named HO1 stock. As a result of analyzing the reduction mechanism, it was made clear that the function is localized in the cellular endosporium and that the reduction is made by utilizing the electronic transfer system of endosporium. Under both aerobic and anaerobic conditions, they convert the hexavalent chrome into the trivalent chrome outside the cells. As a result of test, it was known that 5mM hexavalent chrome can be treated in one day. A quick reduction was confirmed also through an experiment in which carbon source was added to the industrial wastewater. If used for the treatment of sludge/water contaminated by hexavalent chrome, the present reduction by bacteria has the following advantages: The highest reduction rate is given near pH=7 at ordinary temperatures. It is not necessary to add chemicals. Energy is not needed. It is a disadvantageous fact that the present bacteria, if exposed to oxygen, become inactive. 18 refs., 5 figs.

  7. Effect of nano-ZrO2 addition on microstructure, mechanical property and thermal shock behaviour of dense chromic oxide refractory material

    International Nuclear Information System (INIS)

    Lu, Lixia; Ding, Chunhui; Zhanga, Chi; Yanga, De'an; Di, Lizhi

    2015-01-01

    To obtain a good performance hot-face lining material in gasifier, nano-ZrO 2 , up to 5 wt %, was added into chromic oxide powder with 3 wt % TiO 2 followed by sintering at 1500°C for 2.5 h. The effect of nano-ZrO 2 addition on microstructure, mechanical property and thermal shock behaviour was studied. ZrO 2 promoted densification at contents higher than 1 wt %. Microcracks and phase transformation toughened the dense chromic oxide refractory material. The main reason for decrease of strength was the existence microcracks in specimens and weakening of intergranular fracture. Dense chromic oxide refractory material with 2∼3 wt % nano-ZrO 2 possessed good densification, uniform microstructure, normal mechanical property and proper thermal shock resistance. The rupture strength retention ratio was nearly twice than that of chromic oxide material without ZrO 2 after three cycles of quenching test from 950°C to cold water. (author)

  8. Investigation of aluminosilicate refractory for solid oxide fuel cell applications

    Science.gov (United States)

    Gentile, Paul Steven

    Stationary solid oxide fuel cells (SOFCs) have been demonstrated to provide clean and reliable electricity through electro-chemical conversion of various fuel sources (CH4 and other light hydrocarbons). To become a competitive conversion technology the costs of SOFCs must be reduced to less than $400/kW. Aluminosilicate represents a potential low cost alternative to high purity alumina for SOFC refractory applications. The objectives of this investigation are to: (1) study changes of aluminosilicate chemistry and morphology under SOFC conditions, (2) identify volatile silicon species released by aluminosilicates, (3) identify the mechanisms of aluminosilicate vapor deposition on SOFC materials, and (4) determine the effects of aluminosilicate vapors on SOFC electrochemical performance. It is shown thermodynamically and empirically that low cost aluminosilicate refractory remains chemically and thermally unstable under SOFC operating conditions between 800°C and 1000°C. Energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) of the aluminosilicate bulk and surface identified increased concentrations of silicon at the surface after exposure to SOFC gases at 1000°C for 100 hours. The presence of water vapor accelerated surface diffusion of silicon, creating a more uniform distribution. Thermodynamic equilibrium modeling showed aluminosilicate remains stable in dry air, but the introduction of water vapor indicative of actual SOFC gas streams creates low temperature (active anode interface.

  9. Oxidation of refractory sulfur compounds over Ti-containing mesoporous molecular sieves prepared by using a fluorosilicon compound.

    Science.gov (United States)

    Jeong, Kwang-Eun; Cho, Chin-Soo; Chae, Ho-Jeong; Kim, Chul-Ung; Jeong, Soon-Yong

    2010-05-01

    Titanium containing mesoporous molecular sieve (Ti-MMS) catalysts were studied for the oxidative desulfurization of refractory sulfur compounds. Ti-MMS catalysts were synthesized from fluorosilicon compounds and Ti with the hydrolysis reaction of H2SiF6 in an ammonia-surfactant mixed solution. The solid products were characterized by XRD, XRF, nitrogen adsorption, and diffuse reflectance UV-vis spectroscopy. Effects of Ti loading and oxidant/sulfur mole ratio, and sulfur species on ODS activity were investigated.

  10. NASA and ESA Collaboration on Hexavalent Chrome Free Coatings

    Science.gov (United States)

    Greene, Brian

    2017-01-01

    Presentation on the NASA and ESA Collaboration on Hexavalent Chrome Free Coatings project. Project is in response to a Memorandum of Understanding between NASA and ESA Concerning Cooperation in the Field of Space Transportation - signed September 11, 2009. The National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) have expressed mutual interest in pursuing cooperation in the areas of evaluating hexavalent chrome-free coatings, environmentally-preferable coatings for maintenance of launch facilities and ground support equipment, citric acid as an alternative to nitric acid for passivation of stainless steel alloys.

  11. GSDO Program Hexavalent Chrome Alternatives: Final Pretreatments Test Report

    Science.gov (United States)

    Kessel, Kurt

    2013-01-01

    Hexavalent chrome free pretreatments should be considered for use on Ground Support Equipment (OSE) and Electrical Ground Support Equipment (EOSE). Both of the hexavalent chrome free pretreatments (Metalast TCP HF and SurTec 650C) evaluated by this project met, and in some instances exceeded, the requirements ofMIL-DTL-5541 "Chemical Conversion Coatings on Aluminum and Aluminum Alloys". For DC resistance measurements, both Metalast TCP HF and SurTec (!50C met initial requirements following assembly and in many cases continued to maintain passing readings for the duration of testing.

  12. Selective coating for solar panels. [using black chrome and black nickel

    Science.gov (United States)

    Mcdonald, G. E. (Inventor)

    1977-01-01

    The energy absorbing properties of solar heating panels are improved by depositing a black chrome coating of controlled thickness on a specially prepared surface of a metal substrate. The surface is prepared by depositing a dull nickel on the substrate, and the black chrome is plated on this low emittance surface to a thickness between 0.5 micron and 2.5 microns.

  13. A preliminary study of oxidation-resistant coatings on refractory-metal thermocouple sheaths

    International Nuclear Information System (INIS)

    Wilkins, S.C.

    1985-01-01

    The need to make reliable temperature measurements up to 2200 0 C or higher in steam environments during in-pile nuclear fuel damage tests led to a search for oxidation-resistant coatings for the refractory-metal sheaths used to enclose and protect thermocouples used for such measurements. Iridium, thoria, and thoria-over-iridium coatings were separately sputter-deposited on molybdenum-rhenium alloy protection tubes for evaluation. The coated samples were individually heated in flowing steam in an induction furnace. An extension tube welded to each sample was connected to a vacuum pump and gauge; failure of the sample was detected by noting the degradation of the vacuum maintained in the sample. Relatively heavy coatings of iridium provided a modest degree of oxidation protection at the temperatures of interest. Thoria coatings provided no significant protection at those temperatures, compared to uncoated control samples

  14. Microstructural Evolution in Chroming Coatings Friction Pairs under Dry Sliding Test Conditions

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2018-01-01

    Full Text Available The microstructures of subsurface layers of 20CrMnTi steel pins against chroming and nonchroming T10 under dry sliding tests were studied by means of OM (optical microscopy, XRD (X-ray diffraction, and SEM (scanning electron microscopy. Results showed that the chroming coating strengthened the disc surface and significantly affected microstructural evolution. Three layers—the matrix, deformation layer (DL, and surface layer (SL—formed in 20CrMnTi for the chroming T10. The matrix and deformation layer (DL formed in 20CrMnTi for the nonchroming T10. The formation of the microstructure was considered as a result of the shear deformation.

  15. NASA TEERM Hexavalent Chrome Alternatives Projects

    Science.gov (United States)

    Kessel, Kurt; Rothgeb, Matt

    2011-01-01

    This slide presentation reviews the NASA project to select an alternative to hexavalent chrome in the aerospace industry. Included is a recent historic testing and research that the Agency has performed on (1) the external tank, (2) the shuttle orbiter, (3) the Shuttle Rocket Booster, and (4) the Space Shuttle Main Engine. Other related Technology Evaluation for Environmental Risk Mitigation (TEERM) projects are reviewed. The Phase I process of the project performed testing of alternatives the results are shown in a chart for different coating systems. International collaboration was also reviewed. Phase II involves further testing of pretreatment and primers for 6 and 12 months of exposure to conditions at Launch Pad and the beach. Further test were performed to characterize the life cycle corrosion of the space vehicles. A new task is described as a joint project with the Department of Defense to identify a Hex Chrome Free Coatings for Electronics.

  16. Typical corrosion of alumina refractory in aluminum reflow oven

    International Nuclear Information System (INIS)

    Baldo, Jaoa B.

    2014-01-01

    The refractory linings of furnaces for secondary melting of aluminum, are exposed to intense attack by the molten metal. This occurs, because molten aluminum has a strong reducing power over the refractory oxide components, particularly Fe 2 O 3 , SiO 2 and TiO 2 . In this work, based on X-ray diffraction and scanning electron microscopy, it is presented a post mortem study of the mechanisms that lead to a premature wear of a 80% Al2O3 chemically bonded refractory bricks, used in the metal line of an aluminum re-melting furnace. The SEM analysis demonstrated that the oxides SiO 2 and TiO 2 contained in the refractory were reduced and transformed into their metallic elements causing an intense structural spalling. (author)

  17. An investigation into mineral processing of north Semnan refractory earth

    International Nuclear Information System (INIS)

    Aslani, S.; Samin-Bani-Hashemi, H.R.; Taghi-Zadeh, O.

    2002-01-01

    This paper is dealing with refractory earth of North Semnan. Having an area of 2000 square kilometers, Semnan province is mainly formed by sedimentary rocks with a verity of refractory earth, red earth and kaolin containing heavy minerals. The refractory earth of this area contains a considerable rate of aluminum oxide in shape of dia spore minerals, behemoth and gybsite along with heavy minerals of iron and titanium. To improve the quality of refractory earth, in order to be used in related industries, these minerals have to be separated. To assess the quality of refractory earth of North Semnan as the raw materials of refractory industries, their genesis and mineralogy properties have been precisely studied. Based on the rate of aluminium oxide of the refractory earth of North Semnan mines, a suitable mineral deposit has been selected for more investigation. Using XRD and X RF methods along with electronic and photo microscopes, the refractory earth and heavy minerals of them have been assessed. The elementary laboratory experiments of fragmentation and magnetic separation have been performed. It has been proved that the iron minerals can be separated and, therefore, the quality of the refractory earth can be improved. The separation of titanium minerals has to be investigated with other methods

  18. Application of a high-temperature neutron diffraction apparatus to the study of refractory oxides

    International Nuclear Information System (INIS)

    Aldebert, P.; Badie, J.-M.; Buevoz, J.-L.; Roult, G.

    1975-01-01

    A furnace allowing studies of refractory materials by neutron diffraction in situ up to 2500 deg C is described. It is fitted on to a new type of time of flight spectrometer the pulsed source of which is given by a correlation chopper. The advantages of this technique in comparison with fixed-wavelength goniometers are developped. The examination at high temperature of several refractory oxides has been carried out with this experimental device. The thermal expansion curve of α alumina has been established with accuracy up to near the melting point. Several high temperature cristalline forms, X form La 2 O 3 , the tetragonal and cubic ZrO 2 , tetragonal HfO 2 , have been studied. Concerning the latter two, the case of their solid solutions 2MO 2 -M' 2 O 3 (with M=Hf or Zr and M'=La or Y) has also been considered, at room temperature only [fr

  19. Perspectives on environmental protection of refractory metals

    International Nuclear Information System (INIS)

    Perking, R.A.

    1992-01-01

    Alloys of refractory metals which combine high strength to weight ratios with useful low-temperature toughness and ductility have been designed to meet the requirements for the next generation of high-temperature aerospace structural materials with one exception: long term resistance to oxidation. It is considered unlikely that refractory metal alloys can be modified to possess useful resistance to oxidation as bulk materials or that coating can be designed to provide high reliability fail-safe protection for the structural alloys developed to date. Recent developments indicate that bulk alloys of W and Mo can be designed to possess short term resistance to oxidation, providing a base material which can be coated to extend useful life with fail-safe protection in the event of random coating failures. Current research on silicide coatings indicates that significant improvements in coating reliability and performance also are feasible. The technical basis for these conclusions is presented in this paper and the direction of future work that could lead to environmentally stable refractory metal alloy/coating systems is discussed

  20. Determination of tracer quantities of chromium in uranium; Dosage de traces de chrome dans l'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Huart, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    A method is described for the photometric determination of chromium in uranium by absorbency at 540 m{mu} of the Cr(VI) diphenylcarbazide combination. After attack by nitric acid, the solution is made perchloric, and the chromium oxidised at the boiling point by permanganate. Excess oxidant is removed by hydrochloric acid. Study of operating conditions resulted in a method with an accuracy of {+-} 0,5 ppm for 0,5 to 15 ppm chromium in the metal. (author) [French] Le chrome est dose dans l'uranium par photometrie a 540 m{mu} du compose colore Cr(VI) diphenylcarbazide. Apres mise en solution critique et reprise perchlorique a chaud, le chrome est oxyde en milieu acide et a l'ebullition par le permanganate. L'exces d'oxydant est ensuite detruit par l'acide chlorhydrique a l'ebullition. L'etude des conditions experimentales aboutit a un mode operatoire strict. La precision obtenue pour des teneurs comprises entre 0,5 et 15 ppm dans le metal est de 0,5 ppm. (auteur)

  1. SU-E-T-328: Dosimetric Impact of Cobalt-Chrome Stabilization Hardware in Paraspinal Radiation Therapy

    International Nuclear Information System (INIS)

    Tang, G; LoSasso, T; Saleh, Z; Mechalakos, J; Lim, S; Lovelock, D; Laufer, I; Bilsky, M; Yamada, J

    2015-01-01

    Purpose: Due to saturation, high density materials Result in an apparent density of 3.2 g/cm 3 in CT images. The true density of traditional titanium stabilization rods (∼4.4 g/cm 3 ) is typically ignored in treatment planning. This may not be acceptable for new cobalt-chrome rods with a density of 8.5 g/cm 3 . This study reports the dosimetric impact of cobalt-chrome rods in paraspinal radiotherapy. Methods: For titanium and cobalt-chrome rods, two planning studies were done for both IMRT and VMAT in Varian Eclipse using AAA. 1) The effect of planning without assigning the true rod density was assessed by comparing plans generated with the apparent density and recalculated with the true density for titanium and cobalt-chrome. 2) To test if TPS can compensate for high density rods during optimization. Furthermore, TPS calculation accuracy was verified using MapCheck for a single 20 x 10 cm 2 field. The MapCheck was incrementally shifted to achieve measurement resolution of 1 mm. Results: PTV coverage was ∼0.3% and ∼4.7% lower in plans that were recalculated with the true rod density of titanium and cobalt-chrome, respectively. PTV coverage can be maintained if the correct density is used in optimization. Measurements showed that TPS overestimated the dose locally by up to 11% for cobalt-chrome rods and up to 4% for titanium rods if the density is incorrect. With density corrected, maximum local differences of 6% and 3% were seen for cobalt-chrome and titanium rods, respectively. At 2 cm beneath a rod, electrons scattered from the side of the rod increased the lateral dose and diminished as depth increases. TPS was not able to account for this effect properly even with the true rod density assigned. Conclusion: Neglecting the true density of cobalt-chrome rods can cause under coverage to the PTV. Assigning the correct density during treatment planning can minimize unexpected decrease in PTV dose

  2. Chromium Elimination from Water by use of Iron Oxide Nanoparticles Absorbents

    Directory of Open Access Journals (Sweden)

    S Shokraei

    2014-09-01

    Results: results showed that best absorbent is soil absorbent and iron oxide nanoparticles, with maximum removal percent equal to 96.2%. Also best turnover was obtained from 8837 ppm of primary concentration of heavy metal. In other hand, in other experiments that used from iron oxide nanoparticles, adding of nanoparticles caused to increase in chrome absorption and conversion of Cr6+ to Cr3+. Conclusion: with use of the results of this study can be said that Combining of iron oxide nanoparticles with chrome removal filters can be convert Cr6+ to Cr3+, and process turnover will increased.

  3. Preparation of high exhaust chrome from leather shavings and hydrocarbons with its application in leather processing for green tanning technology

    International Nuclear Information System (INIS)

    Nawaz, H.R.; Solangi, B.A.; Nadeem, U.; Zehra, B.

    2010-01-01

    The use of chrome in tanning has made the remarkable advances to achieve the best quality and quantity of leather. But the chrome tanning process is associated with the generation of heavy metal containing solid wastes and toxic effluents. To solve the environmental issues we emphasized on the development of high exhaust chrome complex from chrome containing leather wastes that could minimize the toxic effluents up to negligible limit. Therefore in the synthetic process of chrome tanning material, the chrome shavings and the hydrocarbons have been utilized as a reductant as well as the potential masking intermediates. These chrome tanning materials have been prepared using leather shavings alone in product A, partial replacement of shavings by hydrocarbons for product B and then replacement of hydrocarbons by molasses for product C. The materials have been employed for the tanning of goat skins parallel to the commercial basic chromium sulfate (BCS). (author)

  4. Barrier Coatings for Refractory Metals and Superalloys

    Energy Technology Data Exchange (ETDEWEB)

    SM Sabol; BT Randall; JD Edington; CJ Larkin; BJ Close

    2006-02-23

    In the closed working fluid loop of the proposed Prometheus space nuclear power plant (SNPP), there is the potential for reaction of core and plant structural materials with gas phase impurities and gas phase transport of interstitial elements between superalloy and refractory metal alloy components during service. Primary concerns are surface oxidation, interstitial embrittlement of refractory metals and decarburization of superalloys. In parallel with kinetic investigations, this letter evaluates the ability of potential coatings to prevent or impede communication between reactor and plant components. Key coating requirements are identified and current technology coating materials are reviewed relative to these requirements. Candidate coatings are identified for future evaluation based on current knowledge of design parameters and anticipated environment. Coatings were identified for superalloys and refractory metals to provide diffusion barriers to interstitial transport and act as reactive barriers to potential oxidation. Due to their high stability at low oxygen potential, alumina formers are most promising for oxidation protection given the anticipated coolant gas chemistry. A sublayer of iridium is recommended to provide inherent diffusion resistance to interstitials. Based on specific base metal selection, a thin film substrate--coating interdiffusion barrier layer may be necessary to meet mission life.

  5. Barrier Coatings for Refractory Metals and Superalloys

    International Nuclear Information System (INIS)

    SM Sabol; BT Randall; JD Edington; CJ Larkin; BJ Close

    2006-01-01

    In the closed working fluid loop of the proposed Prometheus space nuclear power plant (SNPP), there is the potential for reaction of core and plant structural materials with gas phase impurities and gas phase transport of interstitial elements between superalloy and refractory metal alloy components during service. Primary concerns are surface oxidation, interstitial embrittlement of refractory metals and decarburization of superalloys. In parallel with kinetic investigations, this letter evaluates the ability of potential coatings to prevent or impede communication between reactor and plant components. Key coating requirements are identified and current technology coating materials are reviewed relative to these requirements. Candidate coatings are identified for future evaluation based on current knowledge of design parameters and anticipated environment. Coatings were identified for superalloys and refractory metals to provide diffusion barriers to interstitial transport and act as reactive barriers to potential oxidation. Due to their high stability at low oxygen potential, alumina formers are most promising for oxidation protection given the anticipated coolant gas chemistry. A sublayer of iridium is recommended to provide inherent diffusion resistance to interstitials. Based on specific base metal selection, a thin film substrate--coating interdiffusion barrier layer may be necessary to meet mission life

  6. Improvement of castable refractories for RH snorkel; RH shinshitsukanyo futeikeizai no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Nishi, K.; Obana, T.; Fijii, T.; Shimizu, I. [Harima Ceramics Corp., Hyogo (Japan)

    1999-11-01

    Relating to corrosion of RH submerged nozzle, resistance against iron oxide of monolithic refractories was examined. Corrosion and seepage of refractories were measured by rotating corrosion, refractories include alumina-spinel castable, which is applied to RH under tank, and alumina-magnesia castable, which is generally used for RH, submerged nozzle. Alumina-spinel castable is superior in resistance against iron oxide than alumina-magnesia castable, and the resistance decreased with increase of stainless fiber addition to castable. Alumina-spinel castable without stainless fiber was suitable for bottom end of the dipping pipe. (NEDO)

  7. Chrome - Free Aluminum Coating System

    Science.gov (United States)

    Bailey, John H.; Gugel, Jeffrey D.

    2010-01-01

    This slide presentation concerns the program to qualify a chrome free coating for aluminum. The program was required due to findings by OSHA and EPA, that hexavalent chromium, used to mitigate corrosion in aerospace aluminum alloys, poses hazards for personnel. This qualification consisted of over 4,000 tests. The tests revealed that a move away from Cr+6, required a system rather than individual components and that the maximum corrosion protection required pretreatment, primer and topcoat.

  8. Oxidation in air of two refractory alloys (Nicral D and Hastelloy X) at 900 and 1100 deg. C

    International Nuclear Information System (INIS)

    Sannier, J.; Dominget, R.; Darras, R.

    1960-01-01

    The oxidation in air of two refractory alloys (Nicral D and Hastelloy X) has been studied at 900 and 1100 deg. C, by means of recording thermo-balances and microscopic cross section examination. At 900 deg. C, the surface oxidation rates of the two alloys are quite similar, but at 1100 deg. C the alloy Nicral D oxidizes faster than the alloy Hastelloy X. On the other hand, after heating at 1100 deg. C for 150 hours, Nicral D shows both intergranular oxidation and a small amount of internal oxidation, whereas Hastelloy X is especially subject to internal oxidation. In addition, two descaling methods were compared: an electrolytic method, in a sodium hydroxide-sodium carbonate bath, and a chemical method using a sodium nitrate-sodium peroxide bath; the latter appears suitable only for Hastelloy X. Reprint of a paper published in Journal of nuclear materials, 3, p. 213-225, 1959 [fr

  9. Influence of thermal treatments on the microstructure and mechanical properties of a HC cast refractory steel

    International Nuclear Information System (INIS)

    Gatica, D; Garin, J; Mannheim, R

    2008-01-01

    The effect of thermal treatments at 750 ( o C) on the microstructure and hardness of a HC cast refractory steel was studied. Samples were extracted from blocks obtained from the melting of this steel, which were heated to 750 ( o C) for 1, 2, 3, 6, 12, 24, 48 and 96 hours and cooled in water. The microstructural analysis was performed using X-ray diffraction, optic and scanning electron microscopy. The phases in each of the samples were quantified using X-ray diffraction, by the direct comparison method, using the DIFRACC-AT, PROFILE FITTING, LATTICE and LAZY-PULVERIX programs. Ferrite was also measured with a magnetic inductor. The phases that were present were ferrite, austenite and Cr 23 C 6 chrome carbides, with a small percentage of molybdenum carbides, slag and non metallic inclusions. As a result of the thermal treatment, the ferrite increased, the austenite decreased and the chrome carbides increased, although their presence varied during the first hours of treatment, displaying a sustained increase only after the 24 hours of heating. Brittle phases, like the sigma phase, did not occur, corroborated by other authors who have noted that for this phase to form there must be preexisting Cr 7 C 3 chrome carbide, as well as Cr 23 C 6 . Temperature impact tests were held in order to determine the temperature of ductile-brittle transition. Unnotched test pieces were submitted to impact trials in a temperature range of 20 to 200 ( o C). This steel does not have a clear transition temperature, but ranges from 50 ( o C) to 80 ( o C )

  10. Wear and creep of highly crosslinked polyethylene against cobalt chrome and ceramic femoral heads.

    Science.gov (United States)

    Galvin, A L; Jennings, L M; Tipper, J L; Ingham, E; Fisher, J

    2010-10-01

    The wear and creep characteristics of highly crosslinked ultrahigh-molecular-weight polyethylene (UHMWPE) articulating against large-diameter (36mm) ceramic and cobalt chrome femoral heads have been investigated in a physiological anatomical hip joint simulator for 10 million cycles. The crosslinked UHMWPE/ceramic combination showed higher volume deformation due to creep plus wear during the first 2 million cycles, and a steady-state wear rate 40 per cent lower than that of the crosslinked UHMWPE/cobalt chrome combination. Wear particles were isolated and characterized from the hip simulator lubricants. The wear particles were similar in size and morphology for both head materials. The particle isolation methodology used could not detect a statistically significant difference between the particles produced by the cobalt chrome and alumina ceramic femoral heads.

  11. Development of technology of complex aluminum-silicon-chrome alloy with utilization of off grade raw materials

    Directory of Open Access Journals (Sweden)

    A. Mekhtiev

    2015-01-01

    Full Text Available Experimental studies on obtaining a complex aluminum-silicon-chrome alloy (FASCh from Karaganda high-ash coals and high-carbon ferrochromefines were carried out. A method for smelting low-carbon ferrochrome using aluminum-silicon-chrome alloy as a reductant is suggested.

  12. NASA TEERM Hexavalent Chrome Alternatives Projects

    Science.gov (United States)

    Kessel, Kurt R.; Rothgeb, Matthew

    2011-01-01

    The overall objective of the Hex Chrome Free Coatings for Electronics project is to evaluate and test pretreatment coating systems not containing hexavalent chrome in avionics and electronics housing applications. This objective will be accomplished by testing strong performing coating systems from prior NASA and DoD testing or new coating systems as determined by the stakeholders. The technical stakeholders have agreed that this protocol will focus specifically on Class 3 coatings. Original Equipment Manufacturers (OEMs), depots, and support contractors have to be prepared to deal with an electronics supply chain that increasingly provides parts with lead-free finishes, some labeled no differently and intermingled with their SnPb counterparts. Allowance of lead-free components presents one of the greatest risks to the reliability of military and aerospace electronics. The introduction of components with lead-free terminations, termination finishes, or circuit boards presents a host of concerns to customers, suppliers, and maintainers of aerospace and military electronic systems such as: 1. Electrical shorting due to tin whiskers 2. Incompatibility of lead-free processes and parameters (including higher melting points of lead-free alloys) with other materials in the system 3. Unknown material properties and incompatibilities that could reduce solder joint reliability

  13. Study of skin and mucous membrane disorders among workers engaged in the sodium dichromate manufacturing industry and chrome plating industry.

    Science.gov (United States)

    Singhal, Vijay Kumar; Deswal, Balbir Singh; Singh, Bachu Narayan

    2015-01-01

    Inhalation of dusts and fumes arising during the manufacture of sodium dichromate from chrome ore, chromic acid mist emitted during electroplating, and skin contact with chromate produce hazards to workers. (1) To elucidate the prevalence of skin and mucous membrane disorders among the workers engaged in the sodium dichromate manufacturing industry and chrome plating industry. (2) To know the relationship of prevalence with the duration of exposure to chrome mist, dust, and fumes. A cross-sectional study was conducted among all the workers engaged in sodium dichromate manufacturing and chrome plating from several industries situated near the Delhi-Haryana border in the districts of Faridabad and Sonepat of Haryana, India from January 01, 2014 to December 31, 2014. All the workers available from the concerned industries for the study were interviewed and medically examined after obtaining their informed consent. A total of 130 workers comprising 66 workers from the sodium dichromate manufacturing industry and 64 workers from the chrome plating industry were examined on a pretested schedule. Descriptive statistical methods (proportions, relative risk, and Chi-square test of significance with P value analyzed using Epi Info version 7). All the workers were found to be males and of the adult age group. Out of the total examined, 69.69% and 56.22% of the workers had disorders of the nasal mucous membrane in the sodium dichromate manufacturing industry and the chrome plating industry, respectively. 42.42% and 28.22% of the workers had perforation of the nasal septum in the sodium dichromate manufacturing industry and chrome plating industry, respectively. 6.06% and 3.12% workers had skin ulcers in the sodium dichromate manufacturing industry and chrome plating industry, respectively. Nasal irritation and rhinorrhea were the most commonly found symptoms in both the processes. 48.48% and 90.52% of the workers were using hand gloves in the sodium dichromate manufacturing

  14. Safety evaluation of traces of nickel and chrome in cosmetics: The case of Dead Sea mud.

    Science.gov (United States)

    Ma'or, Ze'evi; Halicz, Ludwik; Portugal-Cohen, Meital; Russo, Matteo Zanotti; Robino, Federica; Vanhaecke, Tamara; Rogiers, Vera

    2015-12-01

    Metal impurities such as nickel and chrome are present in natural ingredients-containing cosmetic products. These traces are unavoidable due to the ubiquitous nature of these elements. Dead Sea mud is a popular natural ingredient of cosmetic products in which nickel and chrome residues are likely to occur. To analyze the potential systemic and local toxicity of Dead Sea mud taking into consideration Dead Sea muds' natural content of nickel and chrome. The following endpoints were evaluated: (Regulation No. 1223/20, 21/12/2009) systemic and (SCCS's Notes of Guidance) local toxicity of topical application of Dead Sea mud; health reports during the last five years of commercial marketing of Dead Sea mud. Following exposure to Dead Sea mud, MoS (margin of safety) calculations for nickel and chrome indicate no toxicological concern for systemic toxicity. Skin sensitization is also not to be expected by exposure of normal healthy skin to Dead Sea mud. Topical application, however, is not recommended for already nickel-or chrome-sensitized persons. As risk assessment of impurities present in cosmetics may be a difficult exercise, the case of Dead Sea mud is taken here as an example of a natural material that may contain traces of unavoidable metals. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Optical Determination of Lead Chrome Green in Green Tea by Fourier Transform Infrared (FT-IR Transmission Spectroscopy.

    Directory of Open Access Journals (Sweden)

    Xiaoli Li

    Full Text Available The potential of Fourier transform infrared (FT-IR transmission spectroscopy for determination of lead chrome green in green tea was investigated based on chemometric methods. Firstly, the qualitative analysis of lead chrome green in tea was performed based on partial least squares discriminant analysis (PLS-DA, and the correct rate of classification was 100%. And then, a hybrid method of interval partial least squares (iPLS regression and successive projections algorithm (SPA was proposed to select characteristic wavenumbers for the quantitative analysis of lead chrome green in green tea, and 19 wavenumbers were obtained finally. Among these wavenumbers, 1384 (C = C, 1456, 1438, 1419(C = N, and 1506 (CNH cm-1 were the characteristic wavenumbers of lead chrome green. Then, these 19 wavenumbers were used to build determination models. The best model was achieved by least squares support vector machine (LS-SVMalgorithm with high coefficient of determination and low root-mean square error of prediction set (R2p = 0.864 and RMSEP = 0.291. All these results indicated the feasibility of IR spectra for detecting lead chrome green in green tea.

  16. A conceptual model for determining career choice of CHROME alumna based on farmer's conceptual models

    Science.gov (United States)

    Moore, Lisa Simmons

    This qualitative program evaluation examines the career decision-making processes and career choices of nine, African American women who participated in the Cooperating Hampton Roads Organization for Minorities in Engineering (CHROME) and who graduated from urban, rural or suburban high schools in the year 2000. The CHROME program is a nonprofit, pre-college intervention program that encourages underrepresented minority and female students to enter science, technically related, engineering, and math (STEM) career fields. The study describes career choices and decisions made by each participant over a five-year period since high school graduation. Data was collected through an Annual Report, Post High School Questionnaires, Environmental Support Questionnaires, Career Choice Questionnaires, Senior Reports, and standardized open-ended interviews. Data was analyzed using a model based on Helen C. Farmer's Conceptual Models, John Ogbu's Caste Theory and Feminist Theory. The CHROME program, based on its stated goals and tenets, was also analyzed against study findings. Findings indicated that participants received very low levels of support from counselors and teachers to pursue STEM careers and high levels of support from parents and family, the CHROME program and financial backing. Findings of this study also indicated that the majority of CHROME alumna persisted in STEM careers. The most successful participants, in terms of undergraduate degree completion and occupational prestige, were the African American women who remained single, experienced no critical incidents, came from a middle class to upper middle class socioeconomic background, and did not have children.

  17. Plasma deposition of refractories

    International Nuclear Information System (INIS)

    Kudinov, V.V.; Ivanov, V.M.

    1981-01-01

    The problems of deposition, testing and application of plasma coating of refractory metals and oxides are considered. The process fundamentals, various manufacturing procedures and equipment for their realization are described in detail. Coating materials are given (Al, Mg, Al 2 O 3 , ZrO 2 , MgAlO 4 ) which are used in reactor engineering and their designated purposes are shown [ru

  18. Synthesis of Citric-Acrylate Oligomer and its in-Situ Reaction with Chrome Tanned Collagen (hide powder)

    International Nuclear Information System (INIS)

    Haroun, A.A.; Masoud, R.A.; Bronco, S.; Ciardelli, F.

    2005-01-01

    The purpose of this study was to formulate the new combined system of acrylic and citric acids, which has been prepared by free radical polymerization and esterification reaction at the same time to form citric acrylate (CAC) oligomer through ester linkage and low molecular weight (Mw 2241), in compared with polyacrylic acid. The chemical structure and the reaction mechanism of this oligomer were confirmed by different spectroscopic tools (1 H , 13 C-NMR, ATR-IR), gel permeation chromatography and thermogravimetric analysis (TGA/DTA). The problem of the effect of the masking agents in the chrome tanning of the collagen and the pickling of the hide has been approached from the study of the hydrothermal and mechanical properties, using this new eco-friendly oligomer, which was carried out in-situ treated/grafted chrome tanned collagen (hide powder), and pickled hide. The microemulsion grafting copolymerization of (CAC) using 2.2-azo-bis isobutyronitrile (ABIN), via direct coupling reaction, onto the chrome tanned collagen showed that the free amino groups of the collagen were considered to be a potential site for the in-situ reaction with (CAC) oligomer. Also, using of citric-acrylate (CAC) oligomer, during chrome tanning of leather, instead of the traditional strong acids (sulfuric, hydrochloric and formic) resulted in significant improvement in chrome exhaustion and physical properties

  19. Effects of Temperature, Oxygen Partial Pressure, and Materials Selection on Slag Infiltration into Porous Refractories for Entrained-Flow Gasifiers

    Science.gov (United States)

    Kaneko, Tetsuya Kenneth

    The penetration rate of molten mineral contents (slag) from spent carbonaceous feedstock into porous ceramic-oxide refractory linings is a critical parameter in determining the lifecycle of integrated gasification combined cycle energy production plants. Refractory linings that withstand longer operation without interruption are desirable because they can mitigate consumable and maintenance costs. Although refractory degradation has been extensively studied for many other high-temperature industrial processes, this work focuses on the mechanisms that are unique to entrained-flow gasification systems. The use of unique feedstock mixtures, temperatures from 1450 °C to 1600 °C, and oxygen partial pressures from 10-7 atm to 10-9 atm pose engineering challenges in designing an optimal refractory material. Experimentation, characterization, and modeling show that gasifier slag infiltration into porous refractory is determined by interactions between the slag and the refractory that either form a physical barrier that impedes fluid flow or induce an increased fluid viscosity that decelerates the velocity of the fluid body. The viscosity of the slag is modified by the thermal profile of the refractory along the penetration direction as well as reactions between the slag and refractory that alter the chemistry, and thereby the thermo-physical properties of the fluid. Infiltration experiments reveal that the temperature gradient inherently present along the refractory lining limits penetration. A refractory in near-isothermal conditions demonstrates deeper slag penetration as compared to one that experiences a steeper thermal profile. The decrease in the local temperatures of the slag as it travels deeper into the refractory increases the viscosity of the fluid, which in turn slows the infiltration velocity of fluid body into the pores of the refractory microstructure. With feedstock mixtures that exhibit high iron-oxide concentrations, a transition-metal-oxide, the oxygen

  20. Comparative of the Tribological Performance of Hydraulic Cylinders Coated by the Process of Thermal Spray HVOF and Hard Chrome Plating

    Directory of Open Access Journals (Sweden)

    R.M. Castro

    2014-03-01

    Full Text Available Due to the necessity of obtaining a surface that is resistant to wear and oxidation, hydraulic cylinders are typically coated with hard chrome through the process of electroplating process. However, this type of coating shows an increase of the area to support sealing elements, which interferes directly in the lubrication of the rod, causing damage to the seal components and bringing oil leakage. Another disadvantage in using the electroplated hard chromium process is the presence of high level hexavalent chromium Cr+6 which is not only carcinogenic, but also extremely contaminating to the environment. Currently, the alternative process of high-speed thermal spraying (HVOF - High Velocity Oxy-Fuel, uses composite materials (metal-ceramic possessing low wear rates. Research has shown that some mechanical properties are changed positively with the thermal spray process in industrial applications. It is evident that a coating based on WC has upper characteristics as: wear resistance, low friction coefficient, with respect to hard chrome coatings. These characteristics were analyzed by optical microscopy, roughness measurements and wear test.

  1. Le chrome en milieu marin

    OpenAIRE

    Chiffoleau, Jean-francois

    1994-01-01

    Le présent document constitue une synthèse des connaissances sur le cycle biogéochimique du chrome. Les sources naturelles et anthropiques sont étudiées, les échanges entre les différents compartiments géochimiques sont évalués, avec une attention particulière portée à la quantification des apports aussi bien des fleuves que de l'atmosphère au milieu marin. Les niveaux de concentration dans ces compartiments sont évalués, et montrent que l'on rencontre dans certaines régions des contamination...

  2. Validation of HVOF WC/Co Thermal Spray Coatings as a Replacement for Hard Chrome Plating on Aircraft Landing Gear

    National Research Council Canada - National Science Library

    Sartwell, Bruce

    2004-01-01

    .... However, chrome plating utilizes hexavalent chromium, which is a highly toxic carcinogen, and increasingly stringent environmental and worker-safety regulations are making chrome plating more expensive for the DoD...

  3. Ni–Mo–Co ternary alloy as a replacement for hard chrome

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Meenu, E-mail: meenu_srivas@yahoo.co.uk; Anandan, C.; Grips, V.K. William

    2013-11-15

    Hard chrome is the most extensively used electroplated coating in the aerospace and automotive industries due to its attractive properties such as high hardness and excellent wear resistance. However, due to the health risks associated with the use of hexavalent chromium baths during electroplating, there is a need to identify an alternative to this coating. In this study a nickel–molybdenum alloy with cobalt as the alloying element has been developed. The coating was characterized for its micro hardness, wear resistance, coefficient of friction and corrosion resistance. The coating was also subjected to heat treatment at temperatures in the range of 200°–600 °C. It was observed that the micro hardness of Ni–Mo–Co (730 KHN) alloy coating under optimized conditions is apparently quiet similar to that of the most probable substitute Co–P (745 VHN) and hard chrome (800 VHN) coatings. The tribological properties like the wear rate and coefficient of friction of the 400 °C heat treated Ni–Mo–Co coating were noticed to be better compared to hard chrome coating. The electrochemical impedance and polarization studies showed that the corrosion resistance of heat treated Ni–Mo–Co alloy was better than as-deposited Ni–Mo–Co and Ni–Mo coating.

  4. Ni–Mo–Co ternary alloy as a replacement for hard chrome

    International Nuclear Information System (INIS)

    Srivastava, Meenu; Anandan, C.; Grips, V.K. William

    2013-01-01

    Hard chrome is the most extensively used electroplated coating in the aerospace and automotive industries due to its attractive properties such as high hardness and excellent wear resistance. However, due to the health risks associated with the use of hexavalent chromium baths during electroplating, there is a need to identify an alternative to this coating. In this study a nickel–molybdenum alloy with cobalt as the alloying element has been developed. The coating was characterized for its micro hardness, wear resistance, coefficient of friction and corrosion resistance. The coating was also subjected to heat treatment at temperatures in the range of 200°–600 °C. It was observed that the micro hardness of Ni–Mo–Co (730 KHN) alloy coating under optimized conditions is apparently quiet similar to that of the most probable substitute Co–P (745 VHN) and hard chrome (800 VHN) coatings. The tribological properties like the wear rate and coefficient of friction of the 400 °C heat treated Ni–Mo–Co coating were noticed to be better compared to hard chrome coating. The electrochemical impedance and polarization studies showed that the corrosion resistance of heat treated Ni–Mo–Co alloy was better than as-deposited Ni–Mo–Co and Ni–Mo coating.

  5. Elevated Frequencies of Micronuclei and other Nuclear Abnormalities of Chrome Plating Workers Occupationally Exposed to Hexavalent Chromium.

    Science.gov (United States)

    Sudha, S; Kripa, S K; Shibily, P; Shyn, J

    2011-01-01

    Biomonitoring provides a useful tool to estimate the genetic risk from exposure to genotoxic agents. The aim of this study was to assess the potential cytogenetic damage associated with occupational exposure to hexavalent chromium by using micronuclei (MN) as a biomarker. This was a cross-sectional study and all participants were males. Both the exposed and control individuals were selected from Coimbatore, Southern India. Exfoliated buccal cells from 44 chrome plating workers and 40 age and sex matched control subjects were examined for MN frequency and nuclear abnormalities (NA) other than micronuclei, such as binucleates, broken eggs, karyorrhexis, karyolysis and pyknosis. Results showed statistically significant difference between chrome plating workers and control groups. MN and NA frequencies in chrome plating workers were significantly higher than those in control groups (p chrome plating workers are under risk of significant cytogenetic damage. Therefore, there is a need to educate those who work with heavy metals about the potential hazard of occupational exposure and the importance of using protective measures.

  6. Effect of gamma radiation on chrome-tanned sheepskin

    International Nuclear Information System (INIS)

    Kaldirimci, C.

    1982-01-01

    Effect of 60 γ-radiation on chrome-tanned, blue-stock sheepskin was investigated. Radiation was applied between 0.35-10.5 Mrad and the resultant physical and mechanical changes were observed. Radiation did not change the water adsorption capability of leather but caused significant reductions in shrinkage temperature and tensile strength. The correlations between dose and radiation hazards were determined. (author)

  7. The Use Level of Chrome Tannage For Rabbit Fur Leather Observed on Tearing Strength, Stitch Tearing Strength, Water Absorption and Organoleptic

    Directory of Open Access Journals (Sweden)

    Mustakim Mustakim

    2012-02-01

    Full Text Available The purpose of this study was to find out the appropiate of chrome tannage level for rabbit fur leather quality. The result were expected to contribute information for many people who relate with tanning technology, especialy about the use level of chrome tannage for fur leather quality and could as patern to hold further research.The material that used were 12 pieces of three months of rabbit skin. The method is Completely Randomized Design, consist of three treatments of chrome tannage (Chromosal B, they were : B1 (Chromosal B 6%, B2 (Chromosal B 8%, and B3 (Chromosal B 10%. Each of treatment hold on four replications. The variables which measured are tearing strength, stitch teraing strength, water absorption and organoleptic consist of “kekuatan bulu”’ “kerataan bulu” and “kelemasan kulit” in fur leather. Data was analysed by analysis variance followed by Duncan’s Multiple Range Test. The result of this research show that the use level of chromosal B give very significant influence among tearing strength, stitch tearing strength and water absorption. It gave significant influence among the organoleptic test. Based on the result, can be concluded that 10 percent of chrome tannage (chromosal B, produce the best result on tearing strength, stitch tearing strength, water absorption and organoleptic for “kekuatan bulu” and “kerataan bulu”. The incrase of chrome tannage offer will decrease the “kelemasan kulit” in fur leather and the best “kelemasan kulit” produced by the lowest chrome tannage offer, that was 6 percent of Chromosal B. The best quality of rabbit fur leather produced by 10 percent of chrome tannage offer.   Keywords: chrome, tannage, fur leather

  8. Refractory metal particles in refractory inclusions in the Allende meteorite

    International Nuclear Information System (INIS)

    Fuchs, L.H.; Blander, M.

    1980-01-01

    An examination of refractory metal particles in five calcium-aluminum-rich inclusions in the Allende meteorite indicates a complex variety of compositions and large departures from equilibrium. These particles appear to have been primordial condensates which were isolated from the nebula and from each other at different times by cocondensing oxides. Selective diffusion and/or oxidation of the more oxidizable metals (Mo, W, Fe and Ni), phase segregations into different alloy phases (fcc, bcc, hcp and perhaps ordered phases) and the formation of metastable condensates appears to have been involved in the modification of these materials to their present state. Only a small fraction of our observations cannot be reconciled with this picture because of a lack of knowledge of some of the phase equilibria which might have bee involved

  9. SUPERFUND TREATABILITY CLEARINGHOUSE: SOIL STABILIZATION PILOT STUDY, UNITED CHROME NPL SITE PILOT STUDY AND HEALTH AND SAFETY PROGRAM, UNITED CHROME NPL SITE PILOT STUDY

    Science.gov (United States)

    This document is a project plan for a pilot study at the United Chrome NPL site, Corvallis, Oregon and includes the health and safety and quality assurance/quality control plans. The plan reports results of a bench-scale study of the treatment process as iieasured by the ...

  10. Feasibility of Biological Effective Monitoring of Chrome Electroplaters to Chromium through Analysis of Serum Malondialdehyde.

    Science.gov (United States)

    Mozafari, P; Rezazadeh Azari, M; Shokoohi, Y; Sayadi, M

    2016-10-01

    Great concern about occupational exposure to chromium (Cr [VI]) has been reported due to escalated risk of lung cancer in exposed workers. Consequences of occupational exposure to Cr (VI) have been reported as oxidative stress and lung tissue damage. To investigate the feasibility of biological effect monitoring of chrome electroplaters through analysis of serum malondialdehyde (MDA). 90 workers directly involved in chrome electroplating---categorized into three equal groups based on their job as near bath workers, degreaser, and washers---and 30 workers without exposure to Cr (VI), served as the control group, were studied. Personal samples were collected and analyzed according to NIOSH method 7600. Serum MDA level was measured by HPLC using a UV detector. Median Cr (VI) exposure level was 0.38 mg/m(3) in near bath workers, 0.20 mg/m(3) in degreasers, and 0.05 mg/m(3) in washers. The median serum MDA level of three exposed groups (2.76 μmol/L) was significantly (p<0.001) higher than that in the control group (2.00 μmol/L). There was a positive correlation between electroplaters' level of exposure to Cr (VI) and their serum MDA level (Spearman's ρ 0.806, p<0.001). Serum MDA level is a good biomarker for the level of occupational exposure to Cr (VI) in electroplaters.

  11. Feasibility of Biological Effective Monitoring of Chrome Electroplaters to Chromium through Analysis of Serum Malondialdehyde

    Directory of Open Access Journals (Sweden)

    P Mozafari

    2016-10-01

    Full Text Available Background: Great concern about occupational exposure to chromium (Cr [VI] has been reported due to escalated risk of lung cancer in exposed workers. Consequences of occupational exposure to Cr (VI have been reported as oxidative stress and lung tissue damage. Objective: To investigate the feasibility of biological effect monitoring of chrome electroplaters through analysis of serum malondialdehyde (MDA. Methods: 90 workers directly involved in chrome electroplating—categorized into three equal groups based on their job as near bath workers, degreaser, and washers—and 30 workers without exposure to Cr (VI, served as the control group, were studied. Personal samples were collected and analyzed according to NIOSH method 7600. Serum MDA level was measured by HPLC using a UV detector. Results: Median Cr (VI exposure level was 0.38 mg/m3 in near bath workers, 0.20 mg/m3 in degreasers, and 0.05 mg/m3 in washers. The median serum MDA level of three exposed groups (2.76 μmol/L was significantly (p<0.001 higher than that in the control group (2.00 μmol/L. There was a positive correlation between electroplaters' level of exposure to Cr (VI and their serum MDA level (Spearman's ρ 0.806, p<0.001. Conclusion: Serum MDA level is a good biomarker for the level of occupational exposure to Cr (VI in electroplaters.

  12. Primary DNA damage in chrome-plating workers.

    Science.gov (United States)

    Gambelunghe, A; Piccinini, R; Ambrogi, M; Villarini, M; Moretti, M; Marchetti, C; Abbritti, G; Muzi, G

    2003-06-30

    In order to evaluate the primary DNA damage due to occupational exposure to chromium (VI), DNA strand-breaks and apoptosis in peripheral lymphocytes were measured in a group of 19 chrome-plating workers. DNA strand-breaks was assessed by alkaline (pH>13) single-cell microgel electrophoresis ('comet') assay, while apoptosis was measured by flow-cytometry after propidium iodide staining of the cells. Concentrations of chromium in urine, erythrocytes and lymphocytes were investigated as biological indicators of exposure. A group of 18 hospital workers (control group I) and another 20 university personnel (control group II) without exposure to chromium were also studied as controls. The results of the study show that chrome-plating workers have higher levels of chromium in urine, erythrocytes and lymphocytes than unexposed workers. Comet tail moment values, assumed as index of DNA damage, are increased in chromium-exposed workers and results are significantly correlated to chromium lymphocyte concentrations. No difference emerged in the percentage of apoptotic nuclei in exposed and unexposed workers. The study confirms that measurements of chromium in erythrocytes and lymphocytes may provide useful information about recent and past exposure to hexavalent chromium at the workplace. The increase in DNA strand-breaks measured by comet assay suggests this test is valid for the biological monitoring of workers exposed to genotoxic compounds such as chromium (VI).

  13. NASA and ESA Collaboration on Hexavalent Chrome Alternatives: Pretreatments Only Final Test Report

    Science.gov (United States)

    Kessel, Kurt R.

    2015-01-01

    Hexavalent chromium (hex chrome or CR(VI)) is a widely used element within applied coating systems because of its self-healing and corrosion-resistant properties. The replacement of hex chrome in the processing of aluminum for aviation and aerospace applications remains a goal of great significance. Aluminum is the major manufacturing material of structures and components in the space flight arena. The National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) are engaged in a collaborative effort to test and evaluate alternatives to hexavalent chromium containing corrosion coating systems. NASA and ESA share common risks related to material obsolescence associated with hexavalent chromium used in corrosion-resistant coatings.

  14. Production of lightweight refractory material by hydrothermal process

    International Nuclear Information System (INIS)

    Sulejmani, Ramiz B.

    2002-01-01

    Many different processes of production of lightweight refractories are well known over the World. Traditional production of lightweight refractories is by addition of combustibles or by a special frothing process. This work is concerned with hydrothermal of lightweight refractories from rice husk ash. The rice husk ash, used in present investigations were from Kocani region, R. Macedonia. The chemical analysis of the rice husk ash shows that it contains 91,8 - 93,7% SiO 2 and some alkaline and alkaline earth oxides. Microscopic and X - ray diffraction examinations of the rice husk ash have shown that it is composed of cristobalite, tridimite and amorphous silica. The composition of the mixture for lightweight refractory brick production is 93,4% rice husk ash and 6,6% Ca(OH) 2 . The mixtures were well mixed, moistened and pressed at 5 - 10 MPa. The hydrothermal reactions between calcium hydroxide and rice husk ash over the temperature range 80 - 160 o C were investigated. The period of autoclave treatment was from 2 to 72 h. After the hydrothermal treatment of the samples, the mineralogical composition, bulk density, density, cold crushing strength, porosity, refractoriness and thermal expansion were examined. Analysing the properties of the obtained samples it can be concluded that from rice husk ash and calcium hydroxide under hydrothermal condition it is possible to obtain lightweight acid refractory material with high quality.(Author)

  15. Enhancement of the life of refractories through the operational experience of plasma torch melter

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Young Pyo [Technology Institute, Korea Radioactive waste Agency (KORAD), Daejeon (Korea, Republic of); Choi, Jaang Young [Chungnam National University, Daejeon (Korea, Republic of)

    2016-06-15

    The properties of wastes for melting need to be considered to minimize the maintenance of refractory and to discharge the molten slags smoothly from a plasma torch melter. When the nonflammable wastes from nuclear facilities such as concrete debris, glass, sand, etc., are melted, they become acid slags with low basicity since the chemical composition has much more acid oxides than basic oxides. A molten slag does not have good characteristics of discharge and is mainly responsible for the refractory erosion due to its low liquidity. In case of a stationary plasma torch melter with a slant tapping port on the wall, a fixed amount of molten slags remains inside of tapping hole as well as the melter inside after tapping out. Nonmetallic slags keep the temperature higher than melting point of metal because metallic slags located on the bottom of melter by specific gravity difference are simultaneously melted when dual mode plasma torch operates in transferred mode. In order to minimize the refractory erosion, the compatible refractories are selected considering the temperature inside the melter and the melting behavior of slags whether to contact or noncontact with molten slags. An acidic refractory shall not be installed in adjacent to a basic refractory for the resistibility against corrosion.

  16. The Role of Diffusion Media in Nitriding Process on Surface Layers Characteristics of AISI 4140 with and without Hard Chrome Coatings

    Directory of Open Access Journals (Sweden)

    K.A. Widi

    2016-09-01

    Full Text Available The surface layer characteristics of the AISI 4140 tool steel treated by nitriding gas before and after hard chrome plating utilizing pure nitrogen diffusion media (fluidized bed reactor and the without gas (muffle reactor has been studied experimentally. The result shows that nitriding substrate with hard chrome layers has nitrogen atoms concentration almost twice greater than that without hard chrome layers. After being given a hard chrome plating, nitriding on AISI 4140 steel generally has a nitrogen concentration of up to 4 times more than the substrate without hard chrome coating. Almost the entire specimen showed the highest concentration of N atoms in the area below the surface (hardening depth of 200 to 450 µm. N atoms diffusion depth profile has a correlation with hardening depth profile, especially on the specimens layered with hard chromium. The substrate without hard chrome plating tends to have higher surface hardness than the sub-surface. The results show that the effectiveness and efficiency of the gas nitriding diffusion process can be produced without the use of gas in the muffle reactor but the specimens must be hard chromium coated first. This phenomenon can be explained by the role of the passive layer formation that works as a barrier to keeps the spreading of N atoms concentrated in sub-surface areas.

  17. Improvements in or relating to refractory materials

    International Nuclear Information System (INIS)

    Peckett, J.W.A.

    1980-01-01

    A process is described for the production of a refractory material which includes heating an intermediate material containing carbon to cause a thermally induced reaction involving carbon in the intermediate material, wherein the intermediate material has been produced by heating a shaped gel precipitated gel, and the carbon in the intermediate material for participating in the thermally induced reaction has been produced from a gelling agent, or a derivative thereof, incorporated in the gel during gel precipitation. As examples, the refractory material may comprise uranium/plutonium oxide, or uranium/plutonium carbide, or thorium/uranium carbide, or tungsten carbide, or tungsten carbide/cobalt metal. (author)

  18. Porous ceramics out of oxides

    International Nuclear Information System (INIS)

    Bakunov, V.S.; Balkevich, V.L.; Vlasov, A.S.; Guzman, I.Ya.; Lukin, E.S.; Poluboyarinov, D.N.; Poliskij, R.Ya.

    1977-01-01

    A review is made of manufacturing procedures and properties of oxide ceramics intended for high-temperature thermal insulation and thermal protection applications. Presented are structural characteristics of porous oxide refractories and their properties. Strength and thermal conductivity was shown to depend upon porosity. Described is a procedure for manufacturing porous ceramic materials from aluminium oxide, zirconium dioxide, magnesium oxide, beryllium oxide. The thermal resistance of porous ceramics from BeO is considerably greater than that of other high-refractoriness oxides. Listed are areas of application for porous materials based on oxides

  19. Synthesis and characterization of ceramic pigments based on oxides of chromium and iron, on TiO2

    International Nuclear Information System (INIS)

    Silva, E.M. da; Galvao, S.B.; Paskocimas, C.A.

    2011-01-01

    This work used oxides of chromium and iron, as precursors of the synthesis of ceramic pigments. The synthesis is based on the dissolution of citric acid as a complexing agent, addition of metal oxides, such as ion chromophores; polymerization with ethylene glycol and doping with titanium oxide. Passing through pre-calcination, breakdown, calcination at different temperatures (900 and 1100 ° C), resulting in pigments: green for pigment chrome deposited on TiO 2 and orange for iron on TiO 2 . Noticing an increase in the opacity with increasing temperature. The thermal analysis (TG and DTA), evaluated their thermal behavior, the XRD revealed the formation of crystalline phases as Iron Titanate and Chrome Titanate; SEM showed the formation of hexagonal particles for both oxides. Thus, the synthesized oxides were within the requirements for application as ceramic pigments. (author)

  20. Soybean plant growth study conducted using purified protein hydrolysate-based fertilizer made from chrome-tanned leather waste.

    Science.gov (United States)

    Pati, Anupama; Chaudhary, Rubina

    2015-12-01

    Leather processing discharges enormous amount of chrome containing leather solid waste which creates a major disposal problem. Chrome-tanned leather solid waste is a complex of collagen and chromium. The presence of chromium limits protein application in fertilizer industry. The purified protein hydrolysate with zero chromium could be used as a nitrogen source for fertilizer formulation. In this study, an attempt has been made to employ purified protein hydrolysate derived from chrome-tanned leather shavings (CTLS) in formulation of fertilizer. The formulated fertilizer (1–3 t ha(-1)) is employed as nitrogen source in production of soybean. Plant growth study demonstrates that formulated fertilizer dosage 3 t ha(-1) produced similar effects of commercial fertilizer-treated plants. Application of formulated fertilizer yielded higher seed in plant than commercial fertilizer.

  1. Refractory materials based on compounds of Mg, Zr, Si and Ca

    International Nuclear Information System (INIS)

    Drygalska, E.; Piech, J.; Szczerba, J.

    2003-01-01

    Basic refractory materials modified with zirconium oxide or calcium zirconate find application in metallurgy and ceramic industry. Fundamental raw material for ZrO 2 production is zirconia sand, while synthetic calcium zirconate is produced in reaction of zirconium oxide with calcium oxide. Regarding these facts new highly refractory composite materials CZ and DZ were obtained from mixtures of zirconia sand and limestone of dolomite. These composite materials may contain stabilised ZrO 2 and/or calcium zirconate. Among other important components are periclase and calcium orthosilicates. All these phases have high melting points (above 2000 o C). This work describes thermal and technological properties and microstructure of CZ and DZ materials. The use of calcareous raw materials (limestone and dolomite) yields materials with good hydration resistance. These composites may be used as an additive modifying properties of magnesia products. (author)

  2. Selection of the Chrome Reduction Bacteria in the Waste of Tanning Leather Industries by Ozonization Method

    International Nuclear Information System (INIS)

    Yazid, M.; Aris Bastianudin; Widdi Usada

    2007-01-01

    Selection of the chrome reduction bacteria in the waste of tanning leather industries by ozonization method has been done. The objectives of this research was to obtain isolate bacteria from the waste with chrome contain, so that expected can be used for chrome bioremediation agent for arrange to improved the waste treatment for tanning leather industries. Selection of bacteria in the waste was carried out by ozonization method with time variation 0 to 210 minutes by time interval 15 minutes. Isolation bacteria was carried out was grown on the BHI media for 24 hours at 37°C temperature. So be inoculated by streak plate method on the TBX, MC, EA, CTM and BP media. Characterization of bacteria was done by saw the colonies morphology, sel morphology and biochemical characterization. So, identification of isolate bacteria by matching profile method. The result of this research can be obtained 5 isolate bacteria BCR1, BCR2, BCR3, BCR4 and BCR5 with the different phenotypic character. From the five isolate can be selected resistance ozon isolate until 180 minutes time ozonization were BCR 2, were identified belong to the genus of Bacillus. The examination results showed that the isolate bacteria be able to reduction of the chrome concentration in the waste of tanning leather industries by 71.03 %. Efficiency. (author)

  3. Parallel between steels alloyed with chrome-nickel and Fe-Mn-Al-C steels, in their response to fracture and wear (Review)

    International Nuclear Information System (INIS)

    Ramos, J; Perez, G.A

    2008-01-01

    The big worldwide demand for chrome-nickel alloy steels ('conventional steel') leads to the need for advanced materials for applications in different engineering systems that operate at high temperatures and in aggressive environmental conditions, favoring research and development in alternate alloys. In this technological race in search of these new materials, the FeMnAlC alloys ('new steels') have attracted attention for their excellent mechanical and tribological properties as well as for their good performance in corrosive-oxide environments, which make them similar to conventional steel. There are two important similarities between these two steels. First, an agent that causes the passive film to become stainless appears in both steels: chrome in the conventional steel, and aluminum in the FeMnAl alloy. The second similarity is that a stabilizing agent of the austenitic phase (FCC) appears in both, so that excellent mechanical properties can be obtained: nickel in the conventional steel, and manganese in the FeMnAl alloy. In certain sectors, such as aeronautics, conventional steel is rarely used because it is a very heavy material. This conventional steel is almost three times heavier that aluminum (7.85/2.7). Two advantages that the new FeMnAIC steels have compared to the conventional steels are that they are about 13% lighter in weight and they are less expensive. The FeMnAl also have excellent mechanical properties and good corrosion-oxidation resistance, which generates big expectations for their application in a broad scientific spectrum. This work reports the state of the information currently available about FeMnAlC alloys, comparing the mechanical and tribological behaviors of conventional alloy steels with chrome and nickel alloys, specifying the scopes of their application. A condition that favors the steels' fragility is the high speed of deformation and impact, where the FCC crystalline structure materials do not have a fragile ductile transition

  4. Evaluation of refractory materials for a nuclear waste incinerator

    International Nuclear Information System (INIS)

    Grotzky, V.K.; Kneale, P.A.; Teter, A.R.

    1980-01-01

    An experiment to find a suitable refractory lining for a nuclear waste incinerator has been completed. Eleven brick and six castable products were analyzed by optical and scanning microscopy. All the materials were fashioned into cup shapes and subjected to temperatures ranging from 800 to 1200 0 C for as long as six weeks. Some of the cups were charged weekly with pellets made from ash materials that would contact an incinerator liner. Refractory products containing a high percentage of aluminum oxide had the greatest resistance to cracking and slag buildup. 35 figures

  5. Effect of current imbalance on stability of a cable-in-conduit conductor consisting of chrome-plated strands

    International Nuclear Information System (INIS)

    Koizumi, Norikiyo; Takahashi, Yoshikazu; Nishi, Masataka; Isono, Takaaki; Tsuji, Hiroshi; Ono, Michitaka; Hamajima, Takataro; Fujioka, Tsutomu.

    1997-02-01

    The effect of an unbalanced current distribution in a conductor consisting of chrome plated strands on stability was investigated using a cable-in-conduit conductor (CICC) consisting of 27 NbTi chrome-plated strands. In addition, the quench behavior when a non-uniform current distribution was produced in the conductor was studied from the experimental results. Moreover, impedance of the chrome-plated strands was measured using the sample conductor. The results show that the stability is determined by the largest strand current when it is sufficiently large otherwise by the transport current when it is not high enough. It was found that it took a long time to make the conductor quench from the onset of the normal transition of the strand carrying the large current. This is explained by the good diffusivity of the coolant temperature in the conductor's cross section. Since the ramp-rate limitation cannot probably take place if the coolant temperature is diffused well in the conductor's cross section, it is expected the ramp-rate limitation can be prevented using this effect. It is also shown that the chrome-plated strands come into contact with one another with uniform transverse conductance on the order of 10 3 S/m. (author)

  6. Chromatographic characterization of products isolated from chrome shavings

    Directory of Open Access Journals (Sweden)

    Edivaldo E Garcia

    1999-01-01

    Full Text Available Gel permeation chromatography and high performance liquid chromatography were employed for separation and chemical characterization of products isolated from chrome shavings. After enzymatic hydrolysis, the products isolated were peptides of higher molecular weight. Peptides of lower molecular weight and free aminoacids were the main products using sulfuric acid in chrome shavings solubilization. Glycine (17% , glutamic acid (10.6% , alanine (9.2% , and arginine (8.2% were the principal amino acids found. Phenylalanine(1.8% was the main aromatic amino acid , while tryptophane was completely absent.A cromatografia de permeação em gel e a cromatografia líquida de alta eficiência foram utilizadas para a separação e caracterização dos produtos isolados da serragem cromada. Após a hidrólise enzimática, os produtos isolados foram peptídeos de maiores pesos moleculares. Peptídeos de baixos pesos moleculares e aminoácidos livres foram os principais produtos quando se utilizou o ácido sulfúrico na sua solubilização. Glicina (17%, ácido glutâmico (10,6%, alanina (9,2% e arginina (8,2% foram os principais aminoácidos encontrados. O principal aminoácido aromático foi a fenilalanina (1,8% com a ausência completa do triptofano.

  7. Microstructure and properties of high chrome steel roller after laser surface melting

    International Nuclear Information System (INIS)

    Li Meiyan; Wang Yong; Han Bin; Zhao Weimin; Han Tao

    2009-01-01

    Laser surface melting of high chrome steels was achieved by a 5 kW continuous wave CO 2 laser. The microstructure of the laser surface-melted steels was investigated by scanning electron microscopy, transmission electron microscopy and X-ray diffractometry, and the hardness profiles were determined by a Vickers hardness tester. The corrosion behavior in 3.5% NaCl solution was studied by electrochemical corrosion equipment. The large carbides of high chrome steels are completely dissolved and ultrafine dendrites of austenite with submicroscopic M 23 C 6 carbides precipitation are formed in the melted zone. The austenite in the melted zone has a high tempering stability. The corrosion resistance of the laser surface-melted steels is significantly improved due to the dissolution of carbides and the increase of the alloying elements in the solid solution as well as the large amount of austenite.

  8. Development of various welding techniques for refractory and reactive metals and alloys

    International Nuclear Information System (INIS)

    Tonpe, Sunil; Saibaba, N.

    2016-01-01

    Nuclear Fuel Complex (NFC), Hyderabad, India with its excellent manufacturing facilities, produces nuclear fuel and structural components for nuclear reactors. NFC has taken up the challenging job of production of various critical components made out of refractory and reactive metals and alloys for nuclear and aerospace applications as an indigenization import substitute program. Refractory metals are prime candidates for many high temperature aerospace components because of refractory metal's high melting points and inherent creep resistance. The use of refractory metals is often limited because of their poor room temperature properties, inadequate oxidation resistance at elevated temperatures, difficulties associated with joining or welding etc. These advanced materials demand stringent requirement with respect to chemistry, dimensional tolerances, mechanical and metallurgical properties. This paper discusses in detail various welding techniques adopted in NFC for refractory and reactive metals and alloys such as Nb, Zr, Ti, Ta, Zircaloy, Titanium-half alloy etc. to manufacture various components and assemblies required for nuclear and aerospace applications

  9. Characteristics of the chrome-tanned sheep leather treated by radiation-induced graft of BA

    International Nuclear Information System (INIS)

    Zhou Dezhong; Deng Yongzhen; Li Ying

    1986-01-01

    The characteristics of the chrome-tanned sheep leather treated by radiation-induced graft of BA is presented. Using the method of radiation-induced graft of BA instead of the chrome-retanning, the leather has been obviously improved not only in the surface, such as the brightness, fullness, uniformity of the thickness but also in the physical characteristics such as retaining of tensile strength, decreasing of water absorption after being immersed in water for 2h, and 24h, enhancement of tearing strength and stitch tear strength. Although the air permeability and water vapor permeability are a bit worse than the control, however is still in the range of the standard issued by Light Industry Ministry of China

  10. Slagging gasifier refractories. A new pathway to longer refractory life

    Energy Technology Data Exchange (ETDEWEB)

    Schnake, Mark [Harbinson-Walker Refractories Company, Mexico, MO (United States)

    2013-07-01

    Solid fuel slagging gasification to convert coal or petroleum coke feedstocks into syngas has rapidly evolved over the last 25 years. The gasifier is a high temperature, high pressure reaction chamber. Operating temperatures are between 1250 and 1575 C. Pressures will be between 20.4 and 68 atm. Syngas has been typically used for chemical feedstocks, fuel for power plants, or for steam and hydrogen generation in other industrial applications. Ash which comes from the solid fuel during gasification has many impurities. It melts during the gasifier reactor operation forming a liquid that penetrates the refractory lining. Given time, the refractory will wear away from thermal spalling, structural spalling, or overheating of the refractory. In some cases, all three wear mechanisms are seen in the same gasifier lining. Industry users have identified refractory life as one major limiting factor in worldwide use of this technology. Users have stated if the refractory liner can increase on-line availability of the gasifier operation, more industry acceptance of this technology is possible. Harbison-Walker Refractories Company will review destructive factors affecting lining life and discuss new refractory materials that have dramatically increased gasifier lining life and reliability. New refractory materials will be presented and supported by field trial results and post mortem analysis.

  11. Microstructure and properties of high chrome steel roller after laser surface melting

    Energy Technology Data Exchange (ETDEWEB)

    Li Meiyan, E-mail: lmy_102411@163.com [College of Electromechanical Engineering, China University of Petroleum, 271 Bei' er Road, Dongying 257061 (China); Wang Yong; Han Bin; Zhao Weimin; Han Tao [College of Electromechanical Engineering, China University of Petroleum, 271 Bei' er Road, Dongying 257061 (China)

    2009-06-15

    Laser surface melting of high chrome steels was achieved by a 5 kW continuous wave CO{sub 2} laser. The microstructure of the laser surface-melted steels was investigated by scanning electron microscopy, transmission electron microscopy and X-ray diffractometry, and the hardness profiles were determined by a Vickers hardness tester. The corrosion behavior in 3.5% NaCl solution was studied by electrochemical corrosion equipment. The large carbides of high chrome steels are completely dissolved and ultrafine dendrites of austenite with submicroscopic M{sub 23}C{sub 6} carbides precipitation are formed in the melted zone. The austenite in the melted zone has a high tempering stability. The corrosion resistance of the laser surface-melted steels is significantly improved due to the dissolution of carbides and the increase of the alloying elements in the solid solution as well as the large amount of austenite.

  12. High alumina refractories

    International Nuclear Information System (INIS)

    Simao, L.C.; Lopes, A.B.; Galvao Filho, N.B.; Souza, R.B. de

    1989-01-01

    High alumina refractories with 92 to 96.5% Al 2 O 3 were produced using brown and white fused as aggregate. Those refractories present only alumina-α and mullite as crystalline mineralogical phase. Other physical and chemical characteristics are similar to the ones found in refractories produced in Brazil, Japan and U.S.A. The most important physical and chemical tests used for the characterization of the raw materials and refractories, complemented by those realized at high temperatures, plus X-ray Difractometry and optical microscopy are presented, besides the refractory formulation and main parameters of production [pt

  13. RESEARCH OF PROCESS OF AN ALLOYING OF THE FUSED COATINGS RECEIVED FROM THE SUPERFICIAL ALLOYED WIRE BY BORON WITH IN ADDITIONALLY APPLIED ELECTROPLATED COATING OF CHROME AND COPPER

    Directory of Open Access Journals (Sweden)

    V. A. Stefanovich

    2015-01-01

    Full Text Available Researches on distribution of chrome and copper in the fused coating received from the superficial alloyed wire by boron with in additionally applied electroplated coating of chrome and copper were executed. The structure of the fused coating consists of dendrites on which borders the boride eutectic is located. It is established that the content of chrome in dendrites is 1,5– 1,6 times less than in the borid; distribution of copper on structure is uniformed. Coefficients of digestion of chrome and copper at an argon-arc welding from a wire electrode with electroplated coating are established. The assimilation coefficient for chrome is equal to 0,9–1,0; for copper – 0,6–0,75.

  14. Carbothermic reduction of refractory metals

    International Nuclear Information System (INIS)

    Anderson, R.N.; Parlee, N.A.D.

    1976-01-01

    The reduction of stable refractory metal oxides by carbon is generally unacceptable since the product is usually contaminated with carbides. The carbide formation may be avoided by selecting a solvent metal to dissolve the reactive metal as it is produced and reduce its chemical activity below that required for carbide formation. This approach has been successfully applied to the oxides of Si, Zr, Ti, Al, Mg, and U. In the case where a volatile suboxide, a carbonyl reaction, or a volatile metal occur, the use of the solvent metal appears satisfactory to limit the loss of material at low pressures. In several solute--solvent systems, vacuum evaporation is used to strip the solvent metal from the alloy to give the pure metal

  15. Wire winding increases lifetime of oxide coated cathodes

    Science.gov (United States)

    Kerslake, W.; Vargo, D.

    1965-01-01

    Refractory-metal heater base wound with a thin refractory metal wire increases the longevity of oxide-coated cathodes. The wire-wound unit is impregnated with the required thickness of metal oxide. This cathode is useful in magnetohydrodynamic systems and in electron tubes.

  16. Evaluation of tertiary treatments for the reduction of refractory micropollutants in wastewater

    OpenAIRE

    Besnault, S.; Martin Ruel, S.; Baig, S.; Heiniger, B.; Esperanza, M.; Budzinski, H.; Miege, C.; Coquery, M.; Dauthuille, P.

    2012-01-01

    Some refractory micropollutants remain in treated wastewater after secondary treatments. In order to reduce their concentration in treated water, tertiary treatments can be used such as advanced oxidation processes and activated carbon. The efficiency of granular activated carbon in a long term is not well known and advanced oxidation processes have mostly been studied at laboratory scale. Advanced oxidation processes and granular activated carbon pilots were studied in two different wastewat...

  17. Merits of using andalusite-based refractories compared to bauxite-based refractories

    OpenAIRE

    Nyoka, M.; Brazier, D.; Courtney, T.; Parry, R.A.

    2013-01-01

    Historically bauxite-based refractories have been used in applications where andalusite-based refractories could work. Bauxite-based refractories were chosen over andalusite-based refractories mainly because of the availability of low-cost Chinese bauxite and also because many furnaces were designed by international companies that cannot easily access high-quality products. Currently, the availability of low-cost bauxite is under threat as a result of high export duties and tariffs as well as...

  18. Green chemistry approaches to leather tanning process for making chrome-free leather by unnatural amino acids.

    Science.gov (United States)

    Krishnamoorthy, G; Sadulla, S; Sehgal, P K; Mandal, Asit Baran

    2012-05-15

    In the present study, green and sustainable method or eco-friendly approaches to tanning process based on unnatural D-amino acids (D-AA)-aldehyde (Ald) as a substitute for chrome-free tanning has been attempted. The distribution of optically active D-AA in tanned leather, the hydrothermal stability, the mechanical properties and resistance to collagenolytic activity of tanned leather, the evaluation of eco-friendly characteristics were investigated. Scanning electron microscopic (SEM) and Atomic force microscopic (AFM) analyses indicate the surface morphology and roughness, respectively, of the tanned leather collagen matrix. Shrinkage and Differential scanning calorimetric (DSC) analyses shows that the shrinkage temperature (T(s)) and denaturation temperature (T(d)) of tanned leather are related to the content of D-AA+Ald present in the leather matrix. It has been found that the T(s) of D-AA tanned leather is more than that of Ald tanned leather and also more or less equal to chrome tanned leather. Environmental impact assessment (EIA) shows that the developed process results in significant reduction in total solids content (TSC) and improves better biodegradability of organic compound present in the effluent compared to chrome tanning. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Direct brazing of ceramics, graphite, and refractory metals

    International Nuclear Information System (INIS)

    Canonico, D.A.; Cole, N.C.; Slaughter, G.M.

    1976-03-01

    ORNL has been instrumental in the development of brazing filler metals for joining ceramics, graphite, and refractory metals for application at temperatures above 1000 0 C. The philosophy and techniques employed in the development of these alloys are presented. A number of compositions are discussed that have been satisfactorily used to braze ceramics, graphite, and refractory metals without a prior surface treatment. One alloy, Ti--25 percent Cr--21 percent V, has wet and flowed on aluminum oxide and graphite. Further, it has been utilized in making brazes between different combinations of the three subject materials. The excellent flowability of this alloy and alloys from the Ti--Zr--Ge system is evidenced by the presence of filler metal in the minute pores of the graphite and ceramics

  20. PEEK-OPTIMA? as an alternative to cobalt chrome in the femoral component of total knee replacement: A preliminary study

    OpenAIRE

    Cowie, Raelene M; Briscoe, Adam; Fisher, John; Jennings, Louise M

    2016-01-01

    PEEK-OPTIMA™ (Invibio Ltd, UK) has been considered as an alternative joint arthroplasty bearing material due to its favourable mechanical properties and the biocompatibility of its wear debris. In this study, the potential to use injection moulded PEEK-OPTIMA™ as an alternative to cobalt chrome in the femoral component of a total knee replacement was investigated in terms of its wear performance. Experimental wear simulation of three cobalt chrome and three PEEK-OPTIMA™ femoral components art...

  1. Effects of nanodiamonds of explosive synthesis on the skin of experimental animals locally exposed to cobalt and chrome ions.

    Science.gov (United States)

    Prokhorenkov, V I; Vasil'eva, E Yu; Puzyr', A P; Bondar', V S

    2014-12-01

    Experiments in vivo demonstrated the protective effect of modified nanodiamonds on guinea pig skin after local exposure cobalt ions, but not chrome ions. The observed differences are determined by different adsorption of these ions by nanodiamonds: in vitro experiments showed that nanodiamonds adsorbed cobalt ions, but not chrome ions from water solutions. The perspectives of using modified nanodiamonds as a new adsorbent for prevention of allergic contact dermatitis induced by ions of bivalent metals are discussed.

  2. Effects of based Ca O and aluminum ash desulfurization agent on wearing of torpedo car refractories; Acao de agente dessulfurante a base de CaO + Al `ash`sobre o desgaste de refratario de carro torpedo

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Sidiney Nascimento; Marques, Oscar Rosa; Delgado, Paulo Roberto Senna [Companhia Siderurgica Nacional, Volta Redonda, RJ (Brazil); Longo, Elson; Varela, Jose Arana [Sao Carlos Univ., SP (Brazil). Dept. de Quimica; Justus, Sergio Murilo [Universidade Estadual de Ponta Grossa, PR (Brazil). Dept. de Engenharia de Materiais

    1996-12-31

    The introduction oa a new desulfurization agent, at Companhia Siderurgica Nacional (CSN) based Ca O and aluminum ash, have been strongly altered the work conditions of slag line refractories of torpedo car. The wearing mechanism of Al{sub 2} O{sub 3}.Si C.C refractories of torpedo car slag line is as follows: graphite and silicon carbide oxidation by the gas present in torpedo car atmosphere and sodium oxide from process slag; as result from these oxidation reactions, there is a increasing of refractory permeability, simultaneously the silica precipitation in the refractory matrix; the refractory matrix, rich in mullite, strongly reacts with the calcium oxide from slag and silica excess, precipitated from oxidation reactions; as consequence, the formation of low melting point phases occurs which accelerates the wearing of material. (author) 12 refs., 6 figs., 8 tabs.

  3. New applications and novel processing of refractory metal alloys

    International Nuclear Information System (INIS)

    Briant, C.L.

    2001-01-01

    Refractory metals have often been limited in their application because of their propensity to oxidize and to undergo a loos of yield strength at elevated temperatures. However, recent developments in both processing and alloy composition have opened the possibility that these materials might be used in structural applications that were not considered possible in the past. At the same time, the use of refractory metals in the electronics industry is growing, particularly with the use of tantalum as a diffusion barrier for copper metallization. Finally, the application of grain boundary engineering to the problem of intergranular fracture in these materials may allow processes to be developed that will produce alloys with a greater resistance to fracture. (author)

  4. Oxidation of Refractory Benzothiazoles with PMS/CuFe2O4: Kinetics and Transformation Intermediates

    KAUST Repository

    Zhang, Tao; Chen, Yin; Leiknes, TorOve

    2016-01-01

    Benzothiazole (BTH) and its derivatives, 2-(methylthio)bezothiazole (MTBT), 2-benzothiazolsulfonate (BTSA) and 2-hydroxybenzothiazole (OHBT), are refractory pollutants ubiquitously existing in urban runoff at relatively high concentrations. Here, we report their oxidation by CuFe2O4-activated peroxomonosulfate (PMS/CuFe2O4), focusing on kinetics and transformation intermediates. These benzothiazoles can be efficiently degraded by this oxidation process which is confirmed to generate mainly sulfate radicals (with negligible hydroxyl-radical formation) under slightly acidic to neutral pH conditions. The molar exposure ratio of sulfate radical to residual PMS (i.e. Rct) of this process is a constant which is related to reaction condition and can be easily determined. Reaction rate constants of these benzothiazoles towards sulfate radical are (3.3 ± 0.3) × 109, (1.4 ± 0.3) × 109, (1.5 ± 0.1) × 109 and (4.7 ± 0.5) × 109 M-1s-1, respectively (pH 7 and 20 oC). Based on Rct and these rate constants, their degradation in the presence of organic matter can be well predicted. A number of transformation products were detected and tentatively identified using triple-quadruple/linear ion trap MS/MS and high-resolution MS. It appears that sulfate radicals attack BTH, MTBT and BTSA on their benzo ring via electron transfer, generating multiple hydroxylated intermediates which are reactive towards common oxidants. For OHBT oxidation, it prefers to break down the thiazole ring. Due to competitions of the transformation intermediates, a minimum PMS/pollutant molar ratio of 10-20 is required for effective degradation. The flexible PMS/CuFe2O4 could be a useful process to remove the benzothiazoles from low DOC waters like urban runoff or polluted groundwater.

  5. Oxidation of Refractory Benzothiazoles with PMS/CuFe2O4: Kinetics and Transformation Intermediates

    KAUST Repository

    Zhang, Tao

    2016-05-04

    Benzothiazole (BTH) and its derivatives, 2-(methylthio)bezothiazole (MTBT), 2-benzothiazolsulfonate (BTSA) and 2-hydroxybenzothiazole (OHBT), are refractory pollutants ubiquitously existing in urban runoff at relatively high concentrations. Here, we report their oxidation by CuFe2O4-activated peroxomonosulfate (PMS/CuFe2O4), focusing on kinetics and transformation intermediates. These benzothiazoles can be efficiently degraded by this oxidation process which is confirmed to generate mainly sulfate radicals (with negligible hydroxyl-radical formation) under slightly acidic to neutral pH conditions. The molar exposure ratio of sulfate radical to residual PMS (i.e. Rct) of this process is a constant which is related to reaction condition and can be easily determined. Reaction rate constants of these benzothiazoles towards sulfate radical are (3.3 ± 0.3) × 109, (1.4 ± 0.3) × 109, (1.5 ± 0.1) × 109 and (4.7 ± 0.5) × 109 M-1s-1, respectively (pH 7 and 20 oC). Based on Rct and these rate constants, their degradation in the presence of organic matter can be well predicted. A number of transformation products were detected and tentatively identified using triple-quadruple/linear ion trap MS/MS and high-resolution MS. It appears that sulfate radicals attack BTH, MTBT and BTSA on their benzo ring via electron transfer, generating multiple hydroxylated intermediates which are reactive towards common oxidants. For OHBT oxidation, it prefers to break down the thiazole ring. Due to competitions of the transformation intermediates, a minimum PMS/pollutant molar ratio of 10-20 is required for effective degradation. The flexible PMS/CuFe2O4 could be a useful process to remove the benzothiazoles from low DOC waters like urban runoff or polluted groundwater.

  6. Minimization of the environmental impact of chrome tanning: a new process with high chrome exhaustion.

    Science.gov (United States)

    Morera, Josep M; Bacardit, Anna; Ollé, Lluís; Bartolí, Esther; Borràs, Maria D

    2007-11-01

    In all tanning technology operations wastes are generated. These reach the environment as residual waters, solid and liquid waste as well as atmospheric emissions and odours. This study tests an alternative method to the traditional tanning method at an industrial level. The new method is based on tanning without float and by significantly increasing the temperature at the end of the tanning process. The properties of the leathers obtained using the two methods have been compared and the results indicate that those leathers have similar physical, chemical, and organoleptic properties. However, the differences existing from the environmental point of view are significant. It is not necessary to use clean water for this tanning. Moreover, there is a 75% reduction of the residual float, a 91% reduction of the chrome discharged, and a 94% reduction of the chlorides discharged. A financial assessment was carried out to demonstrate that the newly proposed system is 32% more economic than the traditional one.

  7. Refractory Materials for Flame Deflector Protection System Corrosion Control: Refractory Ceramics Literature Survey

    Science.gov (United States)

    Calle, Luz Marina; Hintze, Paul E.; Parlier, Christopher R.; Curran, Jerome P.; Kolody, Mark; Perusich, Stephen; Whitten, Mary C.; Trejo, David; Zidek, Jason; Sampson, Jeffrey W.; hide

    2009-01-01

    Ceramics can be defmed as a material consisting of hard brittle properties produced from inorganic and nonmetallic minerals made by firing at high temperatures. These materials are compounds between metallic and nonmetallic elements and are either totally ionic, or predominately ionic but having some covalent character. This definition allows for a large range of materials, not all applicable to refractory applications. As this report is focused on potential ceramic materials for high temperature, aggressive exposure applications, the ceramics reviewed as part of this report will focus on refractory ceramics specifically designed and used for these applications. Ceramic materials consist of a wide variety of products. Callister (2000) 1 characterized ceramic materials into six classifications: glasses, clay products, refractories, cements, abrasives, and advanced ceramics. Figure 1 shows this classification system. This review will focus mainly on refractory ceramics and cements as in general, the other classifications are neither applicable nor economical for use in large structures such as the flame trench. Although much work has been done in advanced ceramics over the past decade or so, these materials are likely cost prohibitive and would have to be fabricated off-site, transported to the NASA facilities, and installed, which make these even less feasible. Although the authors reviewed the literature on advanced ceramic refractories 2 center dot 3 center dot 4 center dot 5 center dot 6 center dot 7 center dot 8 center dot 9 center dot 10 center dot 11 center dot 12 after the review it was concluded that these materials should not be ' the focus of this report. A review is in progress on materials and systems for prefabricated refractory ceramic panels, but this review is focusing more on typical refractory materials for prefabricated systems, which could make the system more economically feasible. Refractory ceramics are used for a wide variety of applications

  8. Refractory vasculitis

    NARCIS (Netherlands)

    Rutgers, Bram; Kallenberg, Cees G. M.

    Refractory vasculitis occurs in 4-5% of patients with anti-neutrophil cytoplasmic antibody associated vasculitis (AAV). Differences between therapies used for refractory disease are mostly reflected in the percentages of complete and partial remissions, but also in the number of serious side

  9. Radiation-initiated graft polymerization of methyl acrylate onto chrome-tanned sheepskin

    International Nuclear Information System (INIS)

    Kaldirimci, C.; Bas, N.

    1982-01-01

    Radiation grafting method was applied to obtain leather-polymer composite. Grafting of methyl acrylate onto chrome-tanned, bluestock sheepskin was investigated under the initiatory effect of 60 Co radiation of 0.20 11.50 Mrad. The percent of grafting was determined and water adsorption and shrinkage temperature measurements were carried out. It was shown that 2-4 Mrad is convenient to produce leather-polymer composite. (author)

  10. Application of Nuclear methods in the chrome bed prospecting from Casimba sector, Pinares de Mayari

    International Nuclear Information System (INIS)

    Guerra, M.; Velazquez Cruz, R.

    1993-01-01

    A study for chrome determination in Casimba sector, Pinares de Mayari, was carried out using nuclear geophysical methods: and spectrometry neutron-gamma capture. For this purpose Cs 137 and Am-Be sources were used

  11. 40 CFR 425.20 - Applicability; description of the hair save, chrome tan, retan-wet finish subcategory.

    Science.gov (United States)

    2010-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING... cattle-like hides into finished leather by hair save unhairing, chrome tanning, and retan-wet finishing. ...

  12. Refractory oxides for fusion reactor first walls, the effects of the reducing environment

    International Nuclear Information System (INIS)

    Hoffman, J.G.

    1979-01-01

    Of the several applications for refractory oxides in fusion reactor systems, the most demanding is that for the first wall. Some components in proximity of the first wall (possibly waveguides or flux breakers) will also be subjected to similar environments. Many parameters affect the ultimate usability of a particular material for reactor applications: electrical resistivity and dielectric breakdown if applicable, thermal conductivity, mechanical properties, and stability with respect to neutral molecular or atomic, or ionized fuel gases. All these properties can be affected by the radiation environment present in an operating power reactor. Temperatures up to 2000K may be expected for radiatively cooled first wall liners in some proposed designs although surface temperatures are appreciably lower (approximately 1000K) in other applications. The exact nature of the chemical environment is not defined even for the most well developed design concepts, but possible environments may be hypothesized; ambient neutral molecular and atomic species, bombardment by high energy charge exchange neutral atoms, direct ionic bombardment from stray ions, and plasma dumps from failure of the confinement system. Preliminary work has begun to more adequately define the extent of the problem and suggest approaches to engineering solutions

  13. Performance of refractory alloy-clad fuel pins

    International Nuclear Information System (INIS)

    Dutt, D.S.; Cox, C.M.; Millhollen, M.K.

    1984-12-01

    This paper discusses objectives and basic design of two fuel-cladding tests being conducted in support of SP-100 technology development. Two of the current space nuclear power concepts use conventional pin type designs, where a coolant removes the heat from the core and transports it to an out-of-core energy conversion system. An extensive irradiation testing program was conducted in the 1950's and 1960's to develop fuel pins for space nuclear reactors. The program emphasized refractory metal clad uranium nitride (UN), uranium carbide (UC), uranium oxide (UO 2 ), and metal matrix fuels (UCZr and BeO-UO 2 ). Based on this earlier work, studies presented here show that UN and UO 2 fuels in conjunction with several refractory metal cladding materials demonstrated high potential for meeting space reactor requirements and that UC could serve as an alternative but higher risk fuel

  14. Pharmacotherapy for Refractory and Super-Refractory Status Epilepticus in Adults.

    Science.gov (United States)

    Holtkamp, Martin

    2018-03-01

    Patients with prolonged seizures that do not respond to intravenous benzodiazepines and a second-line anticonvulsant suffer from refractory status epilepticus and those with seizures that do not respond to continuous intravenous anesthetic anticonvulsants suffer from super-refractory status epilepticus. Both conditions are associated with significant morbidity and mortality. A strict pharmacological treatment regimen is urgently required, but the level of evidence for the available drugs is very low. Refractory complex focal status epilepticus generally does not require anesthetics, but all intravenous non-anesthetizing anticonvulsants may be used. Most descriptive data are available for levetiracetam, phenytoin and valproate. Refractory generalized convulsive status epilepticus is a life-threatening emergency, and long-term clinical consequences are eminent. Administration of intravenous anesthetics is mandatory, and drugs acting at the inhibitory gamma-aminobutyric acid (GABA) A receptor such as midazolam, propofol and thiopental/pentobarbital are recommended without preference for one of those. One in five patients with anesthetic treatment does not respond and has super-refractory status epilepticus. With sustained seizure activity, excitatory N-methyl-d-aspartate (NMDA) receptors are increasingly expressed post-synaptically. Ketamine is an antagonist at this receptor and may prove efficient in some patients at later stages. Neurosteroids such as allopregnanolone increase sensitivity at GABA A receptors; a Phase 1/2 trial demonstrated safety and tolerability, but randomized controlled data failed to demonstrate efficacy. Adjunct ketogenic diet may contribute to termination of difficult-to-treat status epilepticus. Randomized controlled trials are needed to increase evidence for treatment of refractory and super-refractory status epilepticus, but there are multiple obstacles for realization. Hitherto, prospective multicenter registries for pharmacological

  15. Comparative statistical analysis of chrome and vegetable tanning effluents and their effects on related soil

    International Nuclear Information System (INIS)

    Tariq, Saadia R.; Shah, Munir H.; Shaheen, Nazia

    2009-01-01

    Two tanning units of Pakistan, namely, Kasur and Mian Channun were investigated with respect to the tanning processes (chrome and vegetable, respectively) and the effects of the tanning agents on the quality of soil in vicinity of tanneries were evaluated. The effluent and soil samples from 16 tanneries each of Kasur and Mian Channun were collected. The levels of selected metals (Na, K, Ca, Mg, Fe, Cr, Mn, Co, Cd, Ni, Pb and Zn) were determined by using flame atomic absorption spectrophotometer under optimum analytical conditions. The data thus obtained were subjected to univariate and multivariate statistical analyses. Most of the metals exhibited considerably higher concentrations in the effluents and soils of Kasur compared with those of Mian Channun. It was observed that the soil of Kasur was highly contaminated by Na, K, Ca and Mg emanating from various processes of leather manufacture. Furthermore, the levels of Cr were also present at much enhanced levels than its background concentration due to the adoption of chrome tanning. The levels of Cr determined in soil samples collected from the vicinity of Mian Channun tanneries were almost comparable to the background levels. The soil of this city was found to have contaminated only by the metals originating from pre-tanning processes. The apportionment of selected metals in the effluent and soil samples was determined by a multivariate cluster analysis, which revealed significant differences in chrome and vegetable tanning processes.

  16. Comparative statistical analysis of chrome and vegetable tanning effluents and their effects on related soil.

    Science.gov (United States)

    Tariq, Saadia R; Shah, Munir H; Shaheen, Nazia

    2009-09-30

    Two tanning units of Pakistan, namely, Kasur and Mian Channun were investigated with respect to the tanning processes (chrome and vegetable, respectively) and the effects of the tanning agents on the quality of soil in vicinity of tanneries were evaluated. The effluent and soil samples from 16 tanneries each of Kasur and Mian Channun were collected. The levels of selected metals (Na, K, Ca, Mg, Fe, Cr, Mn, Co, Cd, Ni, Pb and Zn) were determined by using flame atomic absorption spectrophotometer under optimum analytical conditions. The data thus obtained were subjected to univariate and multivariate statistical analyses. Most of the metals exhibited considerably higher concentrations in the effluents and soils of Kasur compared with those of Mian Channun. It was observed that the soil of Kasur was highly contaminated by Na, K, Ca and Mg emanating from various processes of leather manufacture. Furthermore, the levels of Cr were also present at much enhanced levels than its background concentration due to the adoption of chrome tanning. The levels of Cr determined in soil samples collected from the vicinity of Mian Channun tanneries were almost comparable to the background levels. The soil of this city was found to have contaminated only by the metals originating from pre-tanning processes. The apportionment of selected metals in the effluent and soil samples was determined by a multivariate cluster analysis, which revealed significant differences in chrome and vegetable tanning processes.

  17. Comparative statistical analysis of chrome and vegetable tanning effluents and their effects on related soil

    Energy Technology Data Exchange (ETDEWEB)

    Tariq, Saadia R. [Department of Chemistry, Lahore College for Women University, Lahore (Pakistan); Shah, Munir H., E-mail: munir_qau@yahoo.com [Department of Chemistry, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Shaheen, Nazia [Department of Chemistry, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2009-09-30

    Two tanning units of Pakistan, namely, Kasur and Mian Channun were investigated with respect to the tanning processes (chrome and vegetable, respectively) and the effects of the tanning agents on the quality of soil in vicinity of tanneries were evaluated. The effluent and soil samples from 16 tanneries each of Kasur and Mian Channun were collected. The levels of selected metals (Na, K, Ca, Mg, Fe, Cr, Mn, Co, Cd, Ni, Pb and Zn) were determined by using flame atomic absorption spectrophotometer under optimum analytical conditions. The data thus obtained were subjected to univariate and multivariate statistical analyses. Most of the metals exhibited considerably higher concentrations in the effluents and soils of Kasur compared with those of Mian Channun. It was observed that the soil of Kasur was highly contaminated by Na, K, Ca and Mg emanating from various processes of leather manufacture. Furthermore, the levels of Cr were also present at much enhanced levels than its background concentration due to the adoption of chrome tanning. The levels of Cr determined in soil samples collected from the vicinity of Mian Channun tanneries were almost comparable to the background levels. The soil of this city was found to have contaminated only by the metals originating from pre-tanning processes. The apportionment of selected metals in the effluent and soil samples was determined by a multivariate cluster analysis, which revealed significant differences in chrome and vegetable tanning processes.

  18. Radiation induced graft copolymerization of methyl methacrylate onto chrome-tanned pig skins

    International Nuclear Information System (INIS)

    Pietrucha, K.; Pekala, W.; Kroh, J.

    1981-01-01

    Graft copolymerization of methyl methacrylate (MMA) onto chrome-tanned pig skins was carried out by irradiation with 60 Co γ-rays. The grafted polymethyl methacrylate (PMMA) chains were isolated by acid hydrolysis of the collagen backbone in order to characterize the graft copolymers. Proof of grafting was obtained through the detection of amino acid endgroups in the isolated grafts by reaction with ninhydrin. The grafting yield of MMA in aqueous emulsion was found to be higher than that for pure MMA and MMA in acetone. The degree of grafting increases with increasing monomer concentration in emulsion and reaches maximum at radiation dose ca 15 kGy. The yield of grafting is very high. The present paper reports the physical properties of chrome-tanned pig skins after graft polymerization with MMA in emulsion. Modified leathers are more resistant against water absorption and abrasion in comparison with unmodified ones. They have more uniform structure over the whole surface, greater thickness and stiffness. The mechanism of some of the processes occurring during radiation grafting of MMA in water emulsion on tanned leathers has been also suggested and discussed. (author)

  19. Radiation induced graft copolymerization of methyl methacrylate onto chrome-tanned pig skins

    Energy Technology Data Exchange (ETDEWEB)

    Pietrucha, K.; Pekala, W.; Kroh, J. (Lodz Univ. (Poland))

    1981-01-01

    Graft copolymerization of methyl methacrylate (MMA) onto chrome-tanned pig skins was carried out by irradiation with /sup 60/Co ..gamma..-rays. The grafted polymethyl methacrylate (PMMA) chains were isolated by acid hydrolysis of the collagen backbone in order to characterize the graft copolymers. Proof of grafting was obtained through the detection of amino acid endgroups in the isolated grafts by reaction with ninhydrin. The grafting yield of MMA in aqueous emulsion was found to be higher than that for pure MMA and MMA in acetone. The degree of grafting increases with increasing monomer concentration in emulsion and reaches maximum at radiation dose ca 15 kGy. The yield of grafting is very high. The present paper reports the physical properties of chrome-tanned pig skins after graft polymerization with MMA in emulsion. Modified leathers are more resistant against water absorption and abrasion in comparison with unmodified ones. They have more uniform structure over the whole surface, greater thickness and stiffness. The mechanism of some of the processes occurring during radiation grafting of MMA in water emulsion on tanned leathers has been also suggested and discussed.

  20. Surface enrichment with chrome and nitriding of IF steel under an abnormal glow discharge

    International Nuclear Information System (INIS)

    Meira, S.R.; Borges, P.C.; Bernardelli, E.A.

    2014-01-01

    The objective of this work is to evaluate the influence of surface enrichment of IF steel with chrome, and nitriding, the formation of the nitrided layer. Thus, IF steel samples were subjected to surface enrichment process, using 409 stainless steel as a target for sputtering, followed by plasma nitriding, both under a dc abnormal glow discharge. The enrichment treatment was operated at 1200 ° C for 3h. The nitriding treatment was operated at 510 ° C for 2 h. The influence of the treatments on the layers formed was studied through optical microscopy (OM), scan electron microscopy (SEM), X-ray diffraction (XRD) and Vickers microindentation. The results show that the enrichment is effective to enrich the IF surface, furthermore, improves the characteristics of nitriding, comparing nitriding samples to nitriding and enriched, was observed needles of nitrides, as well as a higher hardness, which is associated with the nitrides of chrome, on the nitriding and enriched samples. (author)

  1. Brazing Refractory Metals Used In High-Temperature Nuclear Instrumentation

    International Nuclear Information System (INIS)

    Palmer, A.J.; Woolstenhulme, C.J.

    2009-01-01

    As part of the U. S. Department of Energy (DOE) sponsored Next Generation Nuclear Project (NGNP) currently ongoing at Idaho National Laboratory (INL), the irradiation performance of candidate high-temperature gas reactor fuels and materials is being evaluated at INL's Advanced Test Reactor (ATR). The design of the first Advanced Gas Reactor (AGR 1) experiment, currently being irradiated in the ATR, required development of special techniques for brazing niobium and molybdenum. Brazing is one technique used to join refractory metals to each other and to stainless steel alloys. Although brazing processes are well established, it is difficult to braze niobium, molybdenum, and most other refractory metals because they quickly develop adherent oxides when exposed to room-temperature air. Specialized techniques and methods were developed by INL to overcome these obstacles. This paper describes the techniques developed for removing these oxides, as well as the ASME Section IX-qualified braze procedures that were developed as part of the AGR-1 project. All brazes were made using an induction coil with an inert or reducing atmosphere at low pressure. Other parameters, such as filler metals, fluxes used, and general setup procedures, are also discussed

  2. Brazing refractory metals used in high-temperature nuclear instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A. J. [Idaho National Laboratory, MS 3840, P.O. Box 1625, Idaho Falls, ID 83415-3840 (United States); Woolstenhulme, C. J. [EG and G Services, Inc., (United States)

    2009-07-01

    As part of the U. S. Department of Energy (DOE)-sponsored Next Generation Nuclear Project (NGNP) currently ongoing at Idaho National Laboratory (INL), the irradiation performance of candidate high-temperature gas reactor fuels and materials is being evaluated at INL's Advanced Test Reactor (ATR). The design of the first Advanced Gas Reactor (AGR-1) TRISO fuel experiment, currently being irradiated in the ATR, required development of special techniques for brazing niobium and molybdenum. Brazing is one technique used to join refractory metals to each other and to stainless steel alloys. Although brazing processes are well established, it is difficult to braze niobium, molybdenum, and most other refractory metals because they quickly develop adherent oxides when exposed to room-temperature air. Specialized techniques and methods were developed by INL to overcome these obstacles. This paper describes the techniques developed for removing these oxides, as well as the ASME Section IX-qualified braze procedures that were developed as part of the AGR-1 project. All brazes were made using an induction coil with an inert or reducing atmosphere at low pressure. Other parameters, such as filler metals, fluxes used, and general setup procedures, are also discussed. (authors)

  3. Brazing refractory metals used in high-temperature nuclear instrumentation

    International Nuclear Information System (INIS)

    Palmer, A. J.; Woolstenhulme, C. J.

    2009-01-01

    As part of the U. S. Department of Energy (DOE)-sponsored Next Generation Nuclear Project (NGNP) currently ongoing at Idaho National Laboratory (INL), the irradiation performance of candidate high-temperature gas reactor fuels and materials is being evaluated at INL's Advanced Test Reactor (ATR). The design of the first Advanced Gas Reactor (AGR-1) TRISO fuel experiment, currently being irradiated in the ATR, required development of special techniques for brazing niobium and molybdenum. Brazing is one technique used to join refractory metals to each other and to stainless steel alloys. Although brazing processes are well established, it is difficult to braze niobium, molybdenum, and most other refractory metals because they quickly develop adherent oxides when exposed to room-temperature air. Specialized techniques and methods were developed by INL to overcome these obstacles. This paper describes the techniques developed for removing these oxides, as well as the ASME Section IX-qualified braze procedures that were developed as part of the AGR-1 project. All brazes were made using an induction coil with an inert or reducing atmosphere at low pressure. Other parameters, such as filler metals, fluxes used, and general setup procedures, are also discussed. (authors)

  4. Nucleotide sequence of Hungarian grapevine chrome mosaic nepovirus RNA1.

    OpenAIRE

    Le Gall, O; Candresse, T; Brault, V; Dunez, J

    1989-01-01

    The nucleotide sequence of the RNA1 of hungarian grapevine chrome mosaic virus, a nepovirus very closely related to tomato black ring virus, has been determined from cDNA clones. It is 7212 nucleotides in length excluding the 3' terminal poly(A) tail and contains a large open reading frame extending from nucleotides 216 to 6971. The presumably encoded polyprotein is 2252 amino acids in length with a molecular weight of 250 kDa. The primary structure of the polyprotein was compared with that o...

  5. Method of producing oxidation resistant coatings for molybdenum

    International Nuclear Information System (INIS)

    Timmons, G.A.

    1989-01-01

    A method is described for producing a molybdenum element having adherently bonded thereto a thermally self-healing plasma-sprayed coating consisting essentially of a composite of molybdenum and a refactory oxide material capable of reacting with molybdenum oxide under oxidizing conditions to form a substantially thermally stable refractory compound of molybdenum, the method comprising plasma-spraying a coating formed by the step-wise application of a plurality of interbonded plasma-sprayed layers of a composite of molybdenum/refractory oxide material produced from a particulate mixture thereof. The coating comprises a first layer of molybdenum plasma-sprayed bonded to the substrate of the molybdenum element, a second layer of plasma-sprayed mixture of particulate molybdenum/refactory oxide consisting essentially of predominantly molybdenum bonded to the first layer, and succeeding layers of this mixture. The next step is heating the coated molybdenum element under oxidizing conditions to an elevated temperature sufficient to cause oxygen to diffuse into the surface of the multi-layered coating to react with dispersed molybdenum therein to form molybdenum oxide and effect healing of the coating by reaction of the molybdenum oxide with the contained refractory oxide and thereby protect the substrate of the molybdenum element against oxidation

  6. Separation of motor oils, oily wastes and hydrocarbons from contaminated water by sorption on chrome shavings.

    Science.gov (United States)

    Gammoun, A; Tahiri, S; Albizane, A; Azzi, M; Moros, J; Garrigues, S; de la Guardia, M

    2007-06-25

    In this paper, the ability of chrome shavings to remove motor oils, oily wastes and hydrocarbons from water has been studied. To determine amount of hydrocarbons sorbed on tanned wastes, a FT-NIR methodology was used and a multivariate calibration based on partial least squares (PLS) was employed for data treatment. The light density, porous tanned waste granules float on the surface of water and remove hydrocarbons and oil films. Wastes fibers from tannery industry have high sorption capacity. These tanned solid wastes are capable of absorbing many times their weight in oil or hydrocarbons (6.5-7.6g of oil and 6.3g of hydrocarbons per gram of chrome shavings). The removal efficiency of the pollutants from water is complete. The sorption of pollutants is a quasi-instantaneous process.

  7. CHROME: An Approach to Teaching the Concept of Inter-Functional Cooperation in Services Organizations

    Science.gov (United States)

    Johnson, Lester W.

    2010-01-01

    When teaching a services course (e.g., Services Marketing) it is essential that students understand that marketing/management, operations and human resource management within the service organization be fully coordinated. One useful acronym used to remind students of this need is "CHROME", standing for Communications, Human Resources,…

  8. A useful single-solution polychrome stain for plant material...Brook Cyte-Chrome I.

    Science.gov (United States)

    Stanley L Krugman; Julia F. Littlefield

    1968-01-01

    Fresh and chemically fixed sectioned plant material can be quickly stained by applying a Brook Cyte Chrome I polychrome stain. Staining time averaged only about 10 minutes. And exact timing of staining and de-staining is not as critical as with most of the commonly used stains. The overall quality is comparable to that of the traditional stains.

  9. High temperature oxidation resistant cermet compositions

    Science.gov (United States)

    Phillips, W. M. (Inventor)

    1976-01-01

    Cermet compositions are designed to provide high temperature resistant refractory coatings on stainless steel or molybdenum substrates. A ceramic mixture of chromium oxide and aluminum oxide form a coating of chromium oxide as an oxidation barrier around the metal particles, to provide oxidation resistance for the metal particles.

  10. Fabrication of smooth patterned structures of refractory metals, semiconductors, and oxides via template stripping.

    Science.gov (United States)

    Park, Jong Hyuk; Nagpal, Prashant; McPeak, Kevin M; Lindquist, Nathan C; Oh, Sang-Hyun; Norris, David J

    2013-10-09

    The template-stripping method can yield smooth patterned films without surface contamination. However, the process is typically limited to coinage metals such as silver and gold because other materials cannot be readily stripped from silicon templates due to strong adhesion. Herein, we report a more general template-stripping method that is applicable to a larger variety of materials, including refractory metals, semiconductors, and oxides. To address the adhesion issue, we introduce a thin gold layer between the template and the deposited materials. After peeling off the combined film from the template, the gold layer can be selectively removed via wet etching to reveal a smooth patterned structure of the desired material. Further, we demonstrate template-stripped multilayer structures that have potential applications for photovoltaics and solar absorbers. An entire patterned device, which can include a transparent conductor, semiconductor absorber, and back contact, can be fabricated. Since our approach can also produce many copies of the patterned structure with high fidelity by reusing the template, a low-cost and high-throughput process in micro- and nanofabrication is provided that is useful for electronics, plasmonics, and nanophotonics.

  11. PEEK-OPTIMA™ as an alternative to cobalt chrome in the femoral component of total knee replacement: A preliminary study.

    Science.gov (United States)

    Cowie, Raelene M; Briscoe, Adam; Fisher, John; Jennings, Louise M

    2016-11-01

    PEEK-OPTIMA ™ (Invibio Ltd, UK) has been considered as an alternative joint arthroplasty bearing material due to its favourable mechanical properties and the biocompatibility of its wear debris. In this study, the potential to use injection moulded PEEK-OPTIMA ™ as an alternative to cobalt chrome in the femoral component of a total knee replacement was investigated in terms of its wear performance. Experimental wear simulation of three cobalt chrome and three PEEK-OPTIMA ™ femoral components articulating against all-polyethylene tibial components was carried out under two kinematic conditions: 3 million cycles under intermediate kinematics (maximum anterior-posterior displacement of 5 mm) followed by 3 million cycles under high kinematic conditions (anterior-posterior displacement 10 mm). The wear of the GUR1020 ultra-high-molecular-weight polyethylene tibial components was assessed by gravimetric analysis; for both material combinations under each kinematic condition, the mean wear rates were low, that is, below 5 mm 3 /million cycles. Specifically, under intermediate kinematic conditions, the wear rate of the ultra-high-molecular-weight polyethylene tibial components was 0.96 ± 2.26 mm 3 /million cycles and 2.44 ± 0.78 mm 3 /million cycle against cobalt chrome and PEEK-OPTIMA ™ implants, respectively (p = 0.06); under high kinematic conditions, the wear rates were 2.23 ± 1.85 mm 3 /million cycles and 4.44 ± 2.35 mm 3 /million cycles, respectively (p = 0.03). Following wear simulation, scratches were apparent on the surface of the PEEK-OPTIMA ™ femoral components. The surface topography of the femoral components was assessed using contacting profilometry and showed a statistically significant increase in measured surface roughness of the PEEK-OPTIMA ™ femoral components compared to the cobalt chrome implants. However, this did not appear to influence the wear rate, which remained linear over the duration of

  12. PEEK-OPTIMA™ as an alternative to cobalt chrome in the femoral component of total knee replacement: A preliminary study

    Science.gov (United States)

    Cowie, Raelene M; Briscoe, Adam; Fisher, John; Jennings, Louise M

    2016-01-01

    PEEK-OPTIMA™ (Invibio Ltd, UK) has been considered as an alternative joint arthroplasty bearing material due to its favourable mechanical properties and the biocompatibility of its wear debris. In this study, the potential to use injection moulded PEEK-OPTIMA™ as an alternative to cobalt chrome in the femoral component of a total knee replacement was investigated in terms of its wear performance. Experimental wear simulation of three cobalt chrome and three PEEK-OPTIMA™ femoral components articulating against all-polyethylene tibial components was carried out under two kinematic conditions: 3 million cycles under intermediate kinematics (maximum anterior-posterior displacement of 5 mm) followed by 3 million cycles under high kinematic conditions (anterior-posterior displacement 10 mm). The wear of the GUR1020 ultra-high-molecular-weight polyethylene tibial components was assessed by gravimetric analysis; for both material combinations under each kinematic condition, the mean wear rates were low, that is, below 5 mm3/million cycles. Specifically, under intermediate kinematic conditions, the wear rate of the ultra-high-molecular-weight polyethylene tibial components was 0.96 ± 2.26 mm3/million cycles and 2.44 ± 0.78 mm3/million cycle against cobalt chrome and PEEK-OPTIMA™ implants, respectively (p = 0.06); under high kinematic conditions, the wear rates were 2.23 ± 1.85 mm3/million cycles and 4.44 ± 2.35 mm3/million cycles, respectively (p = 0.03). Following wear simulation, scratches were apparent on the surface of the PEEK-OPTIMA™ femoral components. The surface topography of the femoral components was assessed using contacting profilometry and showed a statistically significant increase in measured surface roughness of the PEEK-OPTIMA™ femoral components compared to the cobalt chrome implants. However, this did not appear to influence the wear rate, which remained linear over the duration of the study. These

  13. Influences of the current density on the performances of the chrome-plated layer in deterministic electroplating repair

    Science.gov (United States)

    Xia, H.; Shen, X. M.; Yang, X. C.; Xiong, Y.; Jiang, G. L.

    2018-01-01

    Deterministic electroplating repair is a novel method for rapidly repairing the attrited parts. By the qualitative contrast and quantitative comparison, influences of the current density on performances of the chrome-plated layer were concluded in this study. The chrome-plated layers were fabricated under different current densities when the other parameters were kept constant. Hardnesses, thicknesses and components, surface morphologies and roughnesses, and wearability of the chrome-plated layers were detected by the Vickers hardness tester, scanning electron microscope / energy dispersive X-ray detector, digital microscope in the 3D imaging mode, and the ball-milling instrument with profilograph, respectively. In order to scientifically evaluate each factor, the experimental data was normalized. A comprehensive evaluation model was founded to quantitative analyse influence of the current density based on analytic hierarchy process method and the weighted evaluation method. The calculated comprehensive evaluation indexes corresponding to current density of 40A/dm2, 45A/dm2, 50A/dm2, 55A/dm2, 60A/dm2, and 65A/dm2 were 0.2246, 0.4850, 0.4799, 0.4922, 0.8672, and 0.1381, respectively. Experimental results indicate that final optimal option was 60A/dm2, and the priority orders were 60A/dm2, 55A/dm2, 45A/dm2, 50A/dm2, 40A/dm2, and 65A/dm2.

  14. Spectrophotometric determination of Sc in eriochrome cyanine R(chrome azurol S) - phosphatidyl choline system

    International Nuclear Information System (INIS)

    Xu, Y.; Chen, X.; Hu, Z.

    1987-01-01

    Eriochrome cyanine R(chrome azurol S) is used as a color reagent to determine Sc in the presence of phosphatidyl choline, eta = 3.7 * 10 4 (4.5 * 10 4 ). This method has been connected to extraction separation to determine Sc in the presence of rare earth elements, and good results have been obtained. Phosphatidyl choline(PC) is a biochemical reagent, which can be used as a surfactant. It has been reported that chrome azurol S(CAS) can be used to determine Be in the presence of PC but it has not been reported that eriochrome cyanine R(ECR) and CAS can been used to determine Sc in the presence of PC. This paper has put forward a method by which Sc can be determined. ECR (CAS) has been used as a color reagent and PC as a surfactant. Conditional experiments have been made and this method has been connected to extraction separation. Tributyl phosphate (TBP) extracts Sc from rare earth elements to make a determination and good results have been obtained

  15. Quantitative chemical microdetermination of beryllium with chrome azurol by the ring-oven technique

    International Nuclear Information System (INIS)

    Hansen, N.B.

    1982-01-01

    A method for determination of beryllium in minerals and rocks is described. Because of the toxicity of beryllium the method is designed for determination of 1-10 ng of Be. The sample is fused with sodium carbonate and sodium tetraborate. Interfering metals are masked with EDTA. Be is determined by the Weisz ring-oven method with Chrome Azurol. The relative error is 10%. (Author)

  16. 40 CFR 425.10 - Applicability; description of the hair pulp, chrome tan, retan-wet finishing subcategory.

    Science.gov (United States)

    2010-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING... addition to other unhairing and tanning operation, processes raw or cured cattle or cattle-like hides into finished leather by chemically dissolving the hide hair, chrome tanning, and retan-wet finishing. ...

  17. Refractoriness in human atria

    DEFF Research Database (Denmark)

    Skibsbye, Lasse; Jespersen, Thomas; Christ, Torsten

    2016-01-01

    BACKGROUND: Refractoriness of cardiac cells limits maximum frequency of electrical activity and protects the heart from tonic contractions. Short refractory periods support major arrhythmogenic substrates and augmentation of refractoriness is therefore seen as a main mechanism of antiarrhythmic...... drugs. Cardiomyocyte excitability depends on availability of sodium channels, which involves both time- and voltage-dependent recovery from inactivation. This study therefore aims to characterise how sodium channel inactivation affects refractoriness in human atria. METHODS AND RESULTS: Steady......-state activation and inactivation parameters of sodium channels measured in vitro in isolated human atrial cardiomyocytes were used to parameterise a mathematical human atrial cell model. Action potential data were acquired from human atrial trabeculae of patients in either sinus rhythm or chronic atrial...

  18. Synthesis and characterization of ceramic pigments based on oxides of chromium and iron, on TiO{sub 2}; Sintese e caracterizacao de pigmentos ceramicos a base de oxidos de cromo e de ferro, depositados sobre TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Silva, E.M. da; Galvao, S.B.; Paskocimas, C.A., E-mail: everlania_siva@yahoo.com.br [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2011-07-01

    This work used oxides of chromium and iron, as precursors of the synthesis of ceramic pigments. The synthesis is based on the dissolution of citric acid as a complexing agent, addition of metal oxides, such as ion chromophores; polymerization with ethylene glycol and doping with titanium oxide. Passing through pre-calcination, breakdown, calcination at different temperatures (900 and 1100 ° C), resulting in pigments: green for pigment chrome deposited on TiO{sub 2} and orange for iron on TiO{sub 2}. Noticing an increase in the opacity with increasing temperature. The thermal analysis (TG and DTA), evaluated their thermal behavior, the XRD revealed the formation of crystalline phases as Iron Titanate and Chrome Titanate; SEM showed the formation of hexagonal particles for both oxides. Thus, the synthesized oxides were within the requirements for application as ceramic pigments. (author)

  19. Green chemistry approaches to leather tanning process for making chrome-free leather by unnatural amino acids

    International Nuclear Information System (INIS)

    Krishnamoorthy, G.; Sadulla, S.; Sehgal, P.K.; Mandal, Asit Baran

    2012-01-01

    Highlights: ► Unnatural D-AA assisted tanned leathers found soft and full possessing tight grain. ► Increased hydrothermal stability of collagen via intra and inter molecular crosslink. ► D-Ly+Ald tanned leathers revealed a properly oriented with well aligned structure. ► D-AA in collagen creates new topologies inaccessible to homo chiral molecules. ► Improves conventional tanning process, and reduce the total solid and liquid wastes. - Abstract: In the present study, green and sustainable method or eco-friendly approaches to tanning process based on unnatural D-amino acids (D-AA)-aldehyde (Ald) as a substitute for chrome-free tanning has been attempted. The distribution of optically active D-AA in tanned leather, the hydrothermal stability, the mechanical properties and resistance to collagenolytic activity of tanned leather, the evaluation of eco-friendly characteristics were investigated. Scanning electron microscopic (SEM) and Atomic force microscopic (AFM) analyses indicate the surface morphology and roughness, respectively, of the tanned leather collagen matrix. Shrinkage and Differential scanning calorimetric (DSC) analyses shows that the shrinkage temperature (T s ) and denaturation temperature (T d ) of tanned leather are related to the content of D-AA+Ald present in the leather matrix. It has been found that the T s of D-AA tanned leather is more than that of Ald tanned leather and also more or less equal to chrome tanned leather. Environmental impact assessment (EIA) shows that the developed process results in significant reduction in total solids content (TSC) and improves better biodegradability of organic compound present in the effluent compared to chrome tanning.

  20. Corrosion assessment of refractory materials for high temperature waste vitrification

    International Nuclear Information System (INIS)

    Marra, J.C.; Congdon, J.W.; Kielpinski, A.L.

    1995-01-01

    A variety of vitrification technologies are being evaluated to immobilize radioactive and hazardous wastes following years of nuclear materials production throughout the Department of Energy (DOE) complex. The compositions and physical forms of these wastes are diverse ranging from inorganic sludges to organic liquids to heterogeneous debris. Melt and off-gas products can be very corrosive at the high temperatures required to melt many of these waste streams. Ensuring material durability is required to develop viable treatment processes. Corrosion testing of materials in some of the anticipated severe environments is an important aspect of the materials identification and selection process. Corrosion coupon tests on typical materials used in Joule heated melters were completed using glass compositions with high salt contents. The presence of chloride in the melts caused the most severe attack. In the metal alloys, oxidation was the predominant corrosion mechanism, while in the tested refractory material enhanced dissolution of the refractory into the glass was observed. Corrosion testing of numerous different refractory materials was performed in a plasma vitrification system using a surrogate heterogeneous debris waste. Extensive corrosion was observed in all tested materials

  1. Plasma spraying of refractory metals and refractory hard materials. State of the art

    International Nuclear Information System (INIS)

    Eschnauer, H.; Lugscheider, E.; Jaeger, D.

    1989-01-01

    Suitable spraying processes for manufacturing refractory metals, refractory hard materials as well as spray materials with refractory components are the VPS- and IPS-spraying techniques. The advantages of these special spraying process variations are described. The reactive spraying materials are systematically organized. The characteristical properties used in purpose of improving the substrate surfaces are explained. Finally some examples of the latest results of research concerning plasma spraying of reactive materials are shown. 16 refs., 10 figs. (Author)

  2. Fracturing of revision of a cobalt-chrome femoral head after fracturing of a ceramic femoral head, with diffuse metallosis. Case report

    Directory of Open Access Journals (Sweden)

    Pedro Miguel Dantas Costa Marques

    2013-04-01

    Full Text Available We presente a case of a fracture of a cobalt-chrome femoral head after revision of a hip total prosthesis with ceramic femoral head fracture. During surgery we found the cobalt-chrome femoral head fracture, wear of the polyethylene and massive metallosis in muscular and cartilaginous tissue. Both femoral stem and acetabular cup were stable and without apparent wearing. After surgical debridement, we promoted the substitution of the femoral head and the acetabular polyethylene by similar ones. After 12 months of follow-up, the patient has no pain complaints, function limit or systemic signs associated with malign metallosis

  3. Ion assisted deposition of refractory oxide thin film coatings for improved optical and structural properties

    International Nuclear Information System (INIS)

    Sahoo, N.K.; Thakur, S.; Bhattacharyya, D.; Das, N.C.

    1999-03-01

    Ion assisted deposition technique (IAD) has emerged as a powerful tool to control the optical and structural properties of thin film coatings. Keeping in view the complexity of the interaction of ions with the films being deposited, sophisticated ion sources have been developed that cater to the need of modern optical coatings with stringent spectral and environmental specifications. In the present work, the results of ion assisted deposition (IAD) of two commonly used refractory oxides, namely TiO 2 and ZrO 2 , using cold cathode ion source (CC-102R) are presented. Through successive feedback and calibration techniques, various ion beams as well as deposition parameters have been optimized to achieve the best optical and structural film properties in the prevalent deposition geometry of the coating system. It has been possible to eliminate the unwanted optical and structural inhomogeneities from these films using and optimized set of process parameters. Interference modulated spectrophotometric and phase modulated ellipsometric techniques have been very successfully utilized to analyze the optical and structural parameters of the films. Several precision multilayer coatings have been developed and are being used for laser and spectroscopic applications. (author)

  4. Ion nitriding post-oxidation as an alternative technique to electrolytic chromium; Nitruracion post-oxidacion ionica como tecnica alternativa al cromado electrolitico

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Guillen, J. C.; Granda-Gutierrez, E.E.; Campa-Castilla, A.; Perez-Aguilar, S.I.; Garza-Gomez, A.; Candelas-Ramirez, J.; Mendez-Mendez, R. [COMIMSA. Corporacion Mexicana de Investigacion en Materiales S.A. de C.V., Saltillo, Coahuila (Mexico)]. E-mail: jcarlos@comimsa.com

    2010-11-15

    The effect of temperature and processing time during post-oxidation on hardness and corrosion resistance of AISI 1045 samples treated through nitriding and post-oxidation in a pulsed plasma discharge is evaluated in this paper. Also, a comparative analysis of the mechanical properties obtained with the dual nitriding - post oxidation process versus those properties of typical hard chrome coatings was performed with an aim to propose an alternative technique to the processes of galvanic coatings. The latter revealed that the process of ion nitriding and post-oxidation provides similar properties in hardness and improves the corrosion resistance compared to the hard chrome case. It is conclude that the technique of ion nitriding and post-oxidation is a non environmental harmful technology with strong potential to replace highly polluting electroplating techniques for application of hard chrome coatings. [Spanish] En el presente trabajo se evalua el efecto del tiempo y la temperatura de post-oxidacion sobre las propiedades de dureza y resistencia a la corrosion de muestras de acero AISI 1045 sometido al proceso de nitruracion post-oxidacion ionica en plasmas pulsados. Asi mismo, con el objetivo de fundamentar la propuesta de utilizacion de la nitruracion post-oxidacion ionica como una tecnica alternativa a los procesos galvanicos para aplicacion de recubrimientos de cromo duro, se realizo un analisis comparativo de propiedades, evidenciando que, mediante el proceso nitruracion postoxidacion ionica, es posible obtener caracteristicas similares en dureza y mejores en resistencia a la corrosion que las tipicas obtenidas para el cromo duro. Los resultados obtenidos permiten postular una tecnica que no dana al medio ambiente, como lo es la nitruracion post-oxidacion ionica, como candidata potencial para sustituir las tecnicas galvanicas altamente contaminantes para aplicacion de cromo duro.

  5. Theoretical and practical aspects about corrosion of refractories used in steel metallurgy: part 3: characterization of commercial refractories

    International Nuclear Information System (INIS)

    Braganca, S.R.

    2012-01-01

    In this study, it was reviewed the main aspects found in the literature about refractories corrosion, evaluating the feasibility of certain tests and relating them with experimental results. The physical properties and microstructure of commercial refractories were analyzed, considering the differences between them and the quality implications and probable life of the refractory. Thus, it was studied the various types of refractories used as lining on steel ladle. Magnesia-carbon and doloma-carbon refractories were analyzed, highlighting the differences between them. The examined refractory showed characteristics favoring high resistance to corrosion process, presenting a series of properties to be selected in accordance with industry practice. (author)

  6. Study of the oxides nature effect of rare and rare earth elements on the aluminium-chromium catalyst properties

    International Nuclear Information System (INIS)

    Dadashev, B.A.; Abbasov, S.G.; Sarydzhanov, A.A.; AN Azerbajdzhanskoj SSR, Baku. Inst. Neftekhimicheskikh Protsessov)

    1975-01-01

    Adsorption studies have shown that oxides of rare and rare earth elements REE appreciably influence the structure of aluminium-chrome catalyst. Alkaline promotors, unlike REE, contribute to the formation of developed contact surface. Electrophysical investigations show that oxides of rare elements introduced into the catalyst increase its conductivity and activation energy. As for REE oxides, they decrease the conductivity and increase the activation energy. Catalysts with developed surface and high conductivity are also more active in the reaction of isopentane dehydration

  7. Green chemistry approaches to leather tanning process for making chrome-free leather by unnatural amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Krishnamoorthy, G.; Sadulla, S.; Sehgal, P.K. [Central Leather Research Institute, Council of Scientific and Industrial Research (CSIR), Adyar, Chennai 600 020 (India); Mandal, Asit Baran, E-mail: abmandal@hotmail.com [Central Leather Research Institute, Council of Scientific and Industrial Research (CSIR), Adyar, Chennai 600 020 (India)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Unnatural D-AA assisted tanned leathers found soft and full possessing tight grain. Black-Right-Pointing-Pointer Increased hydrothermal stability of collagen via intra and inter molecular crosslink. Black-Right-Pointing-Pointer D-Ly+Ald tanned leathers revealed a properly oriented with well aligned structure. Black-Right-Pointing-Pointer D-AA in collagen creates new topologies inaccessible to homo chiral molecules. Black-Right-Pointing-Pointer Improves conventional tanning process, and reduce the total solid and liquid wastes. - Abstract: In the present study, green and sustainable method or eco-friendly approaches to tanning process based on unnatural D-amino acids (D-AA)-aldehyde (Ald) as a substitute for chrome-free tanning has been attempted. The distribution of optically active D-AA in tanned leather, the hydrothermal stability, the mechanical properties and resistance to collagenolytic activity of tanned leather, the evaluation of eco-friendly characteristics were investigated. Scanning electron microscopic (SEM) and Atomic force microscopic (AFM) analyses indicate the surface morphology and roughness, respectively, of the tanned leather collagen matrix. Shrinkage and Differential scanning calorimetric (DSC) analyses shows that the shrinkage temperature (T{sub s}) and denaturation temperature (T{sub d}) of tanned leather are related to the content of D-AA+Ald present in the leather matrix. It has been found that the T{sub s} of D-AA tanned leather is more than that of Ald tanned leather and also more or less equal to chrome tanned leather. Environmental impact assessment (EIA) shows that the developed process results in significant reduction in total solids content (TSC) and improves better biodegradability of organic compound present in the effluent compared to chrome tanning.

  8. High temperature resistant cermet and ceramic compositions. [for thermal resistant insulators and refractory coatings

    Science.gov (United States)

    Phillips, W. M. (Inventor)

    1978-01-01

    High temperature oxidation resistance, high hardness and high abrasion and wear resistance are properties of cermet compositions particularly to provide high temperature resistant refractory coatings on metal substrates, for use as electrical insulation seals for thermionic converters. The compositions comprise a sintered body of particles of a high temperature resistant metal or metal alloy, preferably molybdenum or tungsten particles, dispersed in and bonded to a solid solution formed of aluminum oxide and silicon nitride, and particularly a ternary solid solution formed of a mixture of aluminum oxide, silicon nitride and aluminum nitride. Ceramic compositions comprising a sintered solid solution of aluminum oxide, silicon nitride and aluminum nitride are also described.

  9. Validation of HVOF WC/Co Thermal Spray Coatings as a Replacement for Hard Chrome Plating on Aircraft Landing Gear

    National Research Council Canada - National Science Library

    Sartwell, Bruce

    2004-01-01

    .... This document constitutes the final report on a project to quality high-velocity oxygen-fuel (HVOF) thermal spray WC/Co coatings as a replacement for hard chrome plating on landing gear components...

  10. Poultry feed based on protein hydrolysate derived from chrome-tanned leather solid waste: creating value from waste.

    Science.gov (United States)

    Chaudhary, Rubina; Pati, Anupama

    2016-04-01

    Leather industry generates huge amount of chrome-containing leather solid waste which creates major environment problems to tanners worldwide. Chrome-tanned leather solid waste is primarily chromium complex of collagen protein. The presence of chromium limits its protein application in animal feed industry. The purified protein hydrolysate with zero chromium could be used in poultry feed. In this study, an attempt has been made to assess performance of poultry with purified protein hydrolysate as a feed derived from chrome-tanned leather waste as partial replacement of soyabean meal as a sole source of protein for growing broiler chickens. Growth study was conducted to evaluate the effect of feeding protein hydrolysate on performance and physiochemical characteristics of meat of broiler chickens. Two experimental diets containing various levels of protein hydrolysate (EI-20 % and EII-30 %) were evaluated. The comparative study was performed as control with soyabean meal. Daily feed intake, body weight gain and feed conversion ratio were measured from day 8 to day 35. At the end of the study, birds were randomly selected and slaughtered to evaluate for physiochemical characteristics of meat. Diet had significant effects on feed intake and body weight gain. Birds fed with 20 and 30 % protein hydrolysate consumed 9.5 and 17.5 % higher amount of feed and gained 6.5 and 16.6 % higher than soyabean meal-fed birds. The current study produced evidence that protein hydrolysate can replace up to 75 % of soyabean meal in broiler diets without affecting either growth performance or meat characteristics.

  11. Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

    OpenAIRE

    Malushin, N. N.; Valuev, Denis Viktorovich; Valueva, Anna Vladimirovna; Serikbol, A.; Borovikov, I. F.

    2015-01-01

    The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66).

  12. Hexavalent Chrome Free Coatings for Electronics Applications: Joint Test Report

    Science.gov (United States)

    Kessel, Kurt

    2012-01-01

    Regardless of the corrosivity of the environment, all metals require periodic maintenance activity to guard against the insidious effects of corrosion and thus ensure that alloys meet or exceed design or performance life. The standard practice for protecting metallic substrates is the application of a coating system. Applied coating systems work via a variety of methods (barrier, galvanic, and/or inhibitor) and adhere to the substrate through a combination of chemical and physical bonds. For years hexavalent chromium has been a widely used element within applied coating systems because of its self healing and corrosion resistant properties. Occupational Safety and Health Administration (OSHA) studies have concluded that hexavalent chromium (hex chrome) is carcinogenic and poses significant risk to human health. On May 5, 2011 amendments to the Defense Federal Acquisition Regulation Supplement (DFARS) were issued in the Federal Register. Subpart 223.73 prohibits contracts from requiring hexavalent chromium in deliverables unless certain exceptions apply. These exceptions include authorization from a general or flag officer and members of the Senior Executive Service from a Program Executive Office, and unmodified legacy systems. Otherwise, Subpart 252.223-7008 provides the contract clause prohibiting contractors from using or delivering hexavalent chromium in a concentration greater than 0.1 percent by weight for all new contracts and to be included down to subcontractors for supplies, maintenance and repair services, and construction materials. National Aeronautics and Space Administration (NASA), Department of Defense (DoD), and industry stakeholders continue to search for alternatives to hex chrome in coatings applications that meet their performance requirements in corrosion protection, cost, operability, and health and safety, while typically specifying that performance must be equal to or greater than existing systems.

  13. Removal of refractory organics in nanofiltration concentrates of municipal solid waste leachate treatment plants by combined Fenton oxidative-coagulation with photo--Fenton processes.

    Science.gov (United States)

    Li, Jiuyi; Zhao, Lei; Qin, Lele; Tian, Xiujun; Wang, Aimin; Zhou, Yanmei; Meng, Liao; Chen, Yong

    2016-03-01

    Removal of the refractory organic matters in leachate brines generated from nanofiltration unit in two full-scale municipal solid waste landfill leachate treatment plants was investigated by Fenton oxidative-coagulation and ultraviolet photo - Fenton processes in this study. Fenton oxidative-coagulation was performed under the condition of an initial pH of 5.0 and low H2O2/Fe(2+) ratios. After precipitate separation, the remaining organic constituents were further oxidized by photo - Fenton process. For both leachate brines with varying pollution strength, more than 90% COD and TOC reductions were achieved at H2O2/Fe(2+) dosages of 35 mM/8 mM and 90 mM/10 mM, respectively. The effluent COD ranged 120-160 mg/L under the optimal operating conditions, and the biodegradability was increased significantly. Fenton oxidative-coagulation was demonstrated to contribute nearly 70% overall removal of organic matters. In the combined processes, the efficiency of hydrogen peroxide varied from 216 to 228%, which may significantly reduce the operating cost of conventional Fenton method. Six phthalic acid esters and thirteen polycyclic aromatic hydrocarbons were found in leachate brines, and, on the average, around 80% phthalic acid esters and 90% polycyclic aromatic hydrocarbons were removed by the combined treatments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

    International Nuclear Information System (INIS)

    Malushin, N N; Valuev, D V; Valueva, A V; Serikbol, A; Borovikov, I F

    2015-01-01

    The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66). (paper)

  15. Compatibility of refractory materials with boiling sodium

    International Nuclear Information System (INIS)

    Meacham, S.A.

    1976-01-01

    The program employed to determine the compatibility of commercially available refractories with boiling sodium is described. The effects of impurities contained within the refractory material, and their relations with the refractory's physical stability are discussed. Also, since consideration of refractories for use as an insulating material within Liquid Metal Fast Breeder Reactor Plants (LMFBR's) is currently under investigation; recommendations, based upon this program, are presented

  16. REFRACTORY THROMBOCYTOPENIA AND NEUTROPENIA: A DIAGNOSTIC CHALLENGE

    OpenAIRE

    Emmanuel Gyan; François Dreyfus; Pierre Fenaux

    2015-01-01

    Background. The 2008 WHO classification identified refractory cytopenia with unilineage dysplasia (RCUD) as a composite entity encompassing refractory anemia, refractory thrombocytopenia (RT), and refractory neutropenia (RN), characterized by 10% or more dysplastic cells in the bone marrow respective lineage. The diagnosis of RT and RN is complicated by several factors.  Diagnosing RT first requires exclusion of familial thrombocytopenia, chronic auto-immune thrombocytopenia, concomitant medi...

  17. Thermal behaviour of chrome shavings and of sludges recovered after digestion of tanned solid wastes with calcium hydroxide

    International Nuclear Information System (INIS)

    Tahiri, S.; Albizane, A.; Messaoudi, A.; Azzi, M.; Bennazha, J.; Younssi, S. Alami; Bouhria, M.

    2007-01-01

    The thermal behaviour of chrome shavings and of sludges recovered after digestion of tanned wastes with Ca(OH) 2 was studied. Ashes obtained after incineration of wastes at various temperatures were analysed by X-ray diffraction and EDX method. The main crystallized phases present in the ash obtained at 600 deg. C are Cr 2 O 3 and NaCl. The diffractograms revealed an increase in the intensities of the chromium oxide peaks and a very notable decrease of the amount of sodium chloride at 1100 deg. C. EDX analysis revealed a total disappearance of the chlorine peak at this temperature. Scanning electron micrographs show that the waste lost its fibrous aspect when the temperature increases. Formation of aggregates was noted after 550 deg. C. Combustion of organic matters and decarbonation phenomenon are the main stages observed on GTA and DTA curves of sludges. These phenomena are, respectively, exothermic and endothermic. The diffractogram of sludges recorded at 550 deg. C, in the presence of a constant oxygen surplus, revealed the presence of CaCrO 4 and CaCO 3

  18. Refractory bin for burning

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, D.L.; McPherson, T.L.

    1989-12-26

    This patent describes a refractory bin. It has a generally rectangular horizontal cross sectional configuration. It has wall structures each comprising an upper and a lower pair of elongated horizontal vertically spaced generally parallel support beams each having a vertical flange defining a support edge along its upper surface, a first generally rectangular refractory panel arranged with its lower edge at the bottom of the bin and with its outer surface in flat face contacting relation with the vertical flanges of the lower pair of support beams, a plurality of brackets each having a horizontal part and a vertical part and being secured to the outer surface of the first refractory panel.

  19. Talimogene Laherparepvec and Nivolumab in Treating Patients With Refractory Lymphomas or Advanced or Refractory Non-melanoma Skin Cancers

    Science.gov (United States)

    2018-05-21

    Adenoid Cystic Carcinoma; Adnexal Carcinoma; Apocrine Carcinoma; Eccrine Porocarcinoma; Extraocular Cutaneous Sebaceous Carcinoma; Hidradenocarcinoma; Keratoacanthoma; Malignant Sweat Gland Neoplasm; Merkel Cell Carcinoma; Microcystic Adnexal Carcinoma; NK-Cell Lymphoma, Unclassifiable; Non-Melanomatous Lesion; Paget Disease; Papillary Adenocarcinoma; Primary Cutaneous Mucinous Carcinoma; Refractory Anaplastic Large Cell Lymphoma; Refractory Mature T-Cell and NK-Cell Non-Hodgkin Lymphoma; Refractory Mycosis Fungoides; Refractory Primary Cutaneous T-Cell Non-Hodgkin Lymphoma; Refractory T-Cell Non-Hodgkin Lymphoma; Sezary Syndrome; Signet Ring Cell Carcinoma; Skin Basal Cell Carcinoma; Skin Basosquamous Cell Carcinoma; Skin Squamous Cell Carcinoma; Spiradenocarcinoma; Squamous Cell Carcinoma of Unknown Primary Origin; Stage III Skin Cancer; Stage IV Skin Cancer; Sweat Gland Carcinoma; Trichilemmocarcinoma; Vulvar Squamous Cell Carcinoma

  20. Penanganan limbah krom dengan metode destruksi kimia

    Directory of Open Access Journals (Sweden)

    Suliestiyah Wiryodiningrat

    2007-06-01

    Full Text Available The treatment of chrome waste water was conducted by chemical destruction method. Chromium recovery process that at the same time lowering the chrome content is considered the best solution so far. The treatment of chrome The treatment of chrome waste water was done by chemical process using Magnesium Oxide and Lime to produce Sludge of Chromium performed. By the process of chemical destruction method using Sulphuric Acid, Chrome Sulphate or Chromosal powder that can be used as an alternative tanning agent can be obtained. It can be concluded from the research that destruction process of Chrome Hydroxide Sludge of Lime Process requires speed of stirring 100 rpm. At this state, the content of soluble Solid Substance in Chromium Sulphate Liquor was 5.125 g/l, and the solubility of chromosal in water was 99.15%, whereas for Sludge of Chrome Hydoxide from Magnesium Oxide process, the best speed of stirring was 150 rpm, with soluble solid substance in the Chrome Sulphate was 4.085 g/l and solubility of Chromosal powder in water was 99.54%.

  1. Emergency Surgery for Refractory Status Epilepticus.

    Science.gov (United States)

    Botre, Abhijeet; Udani, Vrajesh; Desai, Neelu; Jagadish, Spoorthy; Sankhe, Milind

    2017-08-15

    Management of refractory status epilepticus in children is extremely challenging. Two children with medically refractory status epilepticus, both of whom had lesional pathology on MRI and concordant data on EEG and PET scan. Emergency hemispherotomy performed in both patients. A complete, sustained seizure freedom obtained postoperatively. Emergency surgery is a treatment option in selected cases of drug refractory status epilepticus with lesional pathology and concordant data.

  2. Nucleotide sequence of Hungarian grapevine chrome mosaic nepovirus RNA1.

    Science.gov (United States)

    Le Gall, O; Candresse, T; Brault, V; Dunez, J

    1989-10-11

    The nucleotide sequence of the RNA1 of hungarian grapevine chrome mosaic virus, a nepovirus very closely related to tomato black ring virus, has been determined from cDNA clones. It is 7212 nucleotides in length excluding the 3' terminal poly(A) tail and contains a large open reading frame extending from nucleotides 216 to 6971. The presumably encoded polyprotein is 2252 amino acids in length with a molecular weight of 250 kDa. The primary structure of the polyprotein was compared with that of other viral polyproteins, revealing the same general genetic organization as that of other picorna-like viruses (comoviruses, potyviruses and picornaviruses), except that an additional protein is suspected to occupy the N-terminus of the polyprotein.

  3. Updates in Refractory Status Epilepticus

    Science.gov (United States)

    Mahulikar, Advait; Suchdev, Kushak; Shah, Aashit

    2018-01-01

    Refractory status epilepticus is defined as persistent seizures despite appropriate use of two intravenous medications, one of which is a benzodiazepine. It can be seen in up to 40% of cases of status epilepticus with an acute symptomatic etiology as the most likely cause. New-onset refractory status epilepticus (NORSE) is a recently coined term for refractory status epilepticus where no apparent cause is found after initial testing. A large proportion of NORSE cases are eventually found to have an autoimmune etiology needing immunomodulatory treatment. Management of refractory status epilepticus involves treatment of an underlying etiology in addition to intravenous anesthetics and antiepileptic drugs. Alternative treatment options including diet therapies, electroconvulsive therapy, and surgical resection in case of a focal lesion should be considered. Short-term and long-term outcomes tend to be poor with significant morbidity and mortality with only one-third of patients reaching baseline neurological status. PMID:29854452

  4. Compositional Variation of Chrome Spinels in the Ore-bearing Zones of the Kraka Ophiolite and the Chromitite Origin

    Directory of Open Access Journals (Sweden)

    D. E. Saveliev

    2017-07-01

    Full Text Available The article considers a chemical variation of accessory and ore-forming chrome spinels from the Kraka ultramafic massif at the different scales, from the deposit to the thin section. A correlation analysis of compositional and structural features of ultramafic rocks and ores was performed. The ultramafic rocks and chromitites in the studied massif show the distinct deformation structures and tectonite olivine fabric. A typical chemical gap (i.e. Cr#=Cr/(Cr+Al was observed between peridotite, on the one hand, and dunite and chromitite, on the other hand, on the scale of deposits and ore-bearing zones. The location and size of this gap depend on the type of deposit. The gap becomes wider from the disseminated tabular bodies to the typical podiform ones. It has been found that in the thin initial dunite veinlets in peridotite the chrome spinels chemistry changes gradually and there is no Cr# gap between peridotite and dunite. The dunite venlets show a strong olivine fabric, which is an evidence of their high-temperature plastic flow origin. It has been revealed that new chrome spinel grains previously formed as rods or needles and then coarsened. We explained this observation as the result of impurity segregation, coalescence and spheroidization induced by the plastic deformation of olivine. It is inferred that a solid crystal flow is the main requirement for the dunite and chromitite body formation in the Kraka ophiolite massif. In the solid stream, the mineral phase separation takes place. For example, olivine and orthopyroxene grains of parental peridotite separate from one another, and weaker (more mobile olivine grains form dunite bodies in which chromitite appears as a result of impurity segregation.

  5. Penanganan Limbah Krom Dengan Metode Destruksi Kimia

    OpenAIRE

    Wiryodiningrat, Suliestiyah; Kismolo, Endro; Prayitno, Prayitno

    2007-01-01

    The treatment of chrome waste water was conducted by chemical destruction method. Chromium recovery process that at the same time lowering the chrome content is considered the best solution so far. The treatment of chrome The treatment of chrome waste water was done by chemical process using Magnesium Oxide and Lime to produce Sludge of Chromium performed. By the process of chemical destruction method using Sulphuric Acid, Chrome Sulphate or Chromosal powder that can be used as an alternative...

  6. Penanganan limbah krom dengan metode destruksi kimia

    OpenAIRE

    Suliestiyah Wiryodiningrat; Endro Kismolo; Prayitno Prayitno

    2007-01-01

    The treatment of chrome waste water was conducted by chemical destruction method. Chromium recovery process that at the same time lowering the chrome content is considered the best solution so far. The treatment of chrome The treatment of chrome waste water was done by chemical process using Magnesium Oxide and Lime to produce Sludge of Chromium performed. By the process of chemical destruction method using Sulphuric Acid, Chrome Sulphate or Chromosal powder that can be used as an alternative...

  7. Refractory status epilepticus

    Directory of Open Access Journals (Sweden)

    Sanjay P Singh

    2014-01-01

    Full Text Available Refractory status epilepticus is a potentially life-threatening medical emergency. It requires early diagnosis and treatment. There is a lack of consensus upon its semantic definition of whether it is status epilepticus that continues despite treatment with benzodiazepine and one antiepileptic medication (AED, i.e., Lorazepam + phenytoin. Others regard refractory status epilepticus as failure of benzodiazepine and 2 antiepileptic medications, i.e., Lorazepam + phenytoin + phenobarb. Up to 30% patients in SE fail to respond to two antiepileptic drugs (AEDs and 15% continue to have seizure activity despite use of three drugs. Mechanisms that have made the treatment even more challenging are GABA-R that is internalized during status epilepticus and upregulation of multidrug transporter proteins. All patients of refractory status epilepticus require continuous EEG monitoring. There are three main agents used in the treatment of RSE. These include pentobarbital or thiopental, midazolam and propofol. RSE was shown to result in mortality in 35% cases, 39.13% of patients were left with severe neurological deficits, while another 13% had mild neurological deficits.

  8. Refractory status epilepticus

    Science.gov (United States)

    Singh, Sanjay P; Agarwal, Shubhi; Faulkner, M

    2014-01-01

    Refractory status epilepticus is a potentially life-threatening medical emergency. It requires early diagnosis and treatment. There is a lack of consensus upon its semantic definition of whether it is status epilepticus that continues despite treatment with benzodiazepine and one antiepileptic medication (AED), i.e., Lorazepam + phenytoin. Others regard refractory status epilepticus as failure of benzodiazepine and 2 antiepileptic medications, i.e., Lorazepam + phenytoin + phenobarb. Up to 30% patients in SE fail to respond to two antiepileptic drugs (AEDs) and 15% continue to have seizure activity despite use of three drugs. Mechanisms that have made the treatment even more challenging are GABA-R that is internalized during status epilepticus and upregulation of multidrug transporter proteins. All patients of refractory status epilepticus require continuous EEG monitoring. There are three main agents used in the treatment of RSE. These include pentobarbital or thiopental, midazolam and propofol. RSE was shown to result in mortality in 35% cases, 39.13% of patients were left with severe neurological deficits, while another 13% had mild neurological deficits. PMID:24791086

  9. Characterization of emission factors related to source activity for trichloroethylene degreasing and chrome plating processes.

    Science.gov (United States)

    Wadden, R A; Hawkins, J L; Scheff, P A; Franke, J E

    1991-09-01

    A study at an automotive parts fabrication plant evaluated four metal surface treatment processes during production conditions. The evaluation provides examples of how to estimate process emission factors from activity and air concentration data. The processes were open tank and enclosed tank degreasing with trichloroethylene (TCE), chromium conversion coating, and chromium electroplating. Area concentrations of TCE and chromium (Cr) were monitored for 1-hr periods at three distances from each process. Source activities at each process were recorded during each sampling interval. Emission rates were determined by applying appropriate mass balance models to the concentration patterns around each source. The emission factors obtained from regression analysis of the emission rate and activity data were 16.9 g TCE/basket of parts for the open-top degreaser; 1.0 g TCE/1000 parts for the enclosed degreaser; 1.48-1.64 mg Cr/1000 parts processed in the hot CrO3/HNO3 tank for the chrome conversion coating; and 5.35-9.17 mg Cr/rack of parts for chrome electroplating. The factors were also used to determine the efficiency of collection for the local exhaust systems serving each process. Although the number of observations were limited, these factors may be useful for providing initial estimates of emissions from similar processes in other settings.

  10. Development of refractory concrete for extreme conditions

    International Nuclear Information System (INIS)

    Pundiene, I; Antonovich, V; Stonys, R; Demidova-Buiziniene, I

    2011-01-01

    Comparative analysis is provided for the properties of medium-cement refractory concrete with microsilica based on mullite filler in relation to different type of deflocculant. The effect of different deflocculants on refractory concrete structure formation, hydration, rheology, strength and heat resistance is discussed. Corrosion resistance test, determined that samples with hybrid deflocculant showed better resistance for slag penetration than samples with only the sodium tripolyphosphate or polycarboxylate ether deflocculant. Moreover, a composition of hybrid deflocculant let to control the rate of the hydration process and to get features of refractory refractory concrete.

  11. High-Density Infrared Surface Treatments of Refractories

    Energy Technology Data Exchange (ETDEWEB)

    Tiegs, T.N.

    2005-03-31

    Refractory materials play a crucial role in all energy-intensive industries and are truly a crosscutting technology for the Industries of the Future (IOF). One of the major mechanisms for the degradation of refractories and a general decrease in their performance has been the penetration and corrosion by molten metals or glass. Methods and materials that would reduce the penetration, wetting, and corrosive chemistry would significantly improve refractory performance and also maintain the quality of the processed liquid, be it metal or glass. This report presents the results of an R&D project aimed at investigating the use of high-density infrared (HDI) heating to surface treat refractories to improve their performance. The project was a joint effort between Oak Ridge National Laboratory (ORNL) and the University of Missouri-Rolla (UMR). HDI is capable of heating the near-surface region of materials to very high temperatures where sintering, diffusion, and melting can occur. The intended benefits of HDI processing of refractories were to (1) reduce surface porosity (by essentially sealing the surface to prevent liquid penetration), (2) allow surface chemistry changes to be performed by bonding an adherent coating onto the underlying refractory (in order to inhibit wetting and/or improve corrosion resistance), and (3) produce noncontact refractories with high-emissivity surface coatings.

  12. Google Chrome OS: Cultural influence on product launch strategy between India and developed countries

    OpenAIRE

    Santhosh, Arjun

    2011-01-01

    In recent times product launch has become vital deciding factor in the success of a product. The significance of product launch becomes even higher if the product is radically new and different from existing products in the market. The aim of this dissertation is to look into the possible factors which might influence the product launch of Google Chrome Operating System that has radical concepts and design. The essential variations which might be needed for the successful launch in India as c...

  13. Genetics Home Reference: iron-refractory iron deficiency anemia

    Science.gov (United States)

    ... refractory iron deficiency anemia Iron-refractory iron deficiency anemia Printable PDF Open All Close All Enable Javascript ... expand/collapse boxes. Description Iron-refractory iron deficiency anemia is one of many types of anemia , which ...

  14. PHOTOCATALYTIC REMOVAL OF TR I- AND HEXA-VALENT CHROMIUM IONS FROM CHROME-ELECTROPL ATING WASTEWATER

    OpenAIRE

    Puangrat Kajitvichyanukul; Chulaluck Changul

    2017-01-01

    A novel technique based on photocatalysis was applied to eliminate chromium ions, a toxic hazardous environmental pollutant. The photoreduction of each species of chromium (total, hexavalent, and trivalent chromiums) from chrome-electroplating wastewater was investigated using a titanium dioxide suspension under irradiation by a low-pressure mercury lamp. The initial concentration of total chromium was 300 mg/l. The applied conditions were the direct photocatalytic reduction process at pH 3.6...

  15. Refractory hypertension: definition, prevalence, and patient characteristics.

    Science.gov (United States)

    Acelajado, Maria Czarina; Pisoni, Roberto; Dudenbostel, Tanja; Dell'Italia, Louis J; Cartmill, Falynn; Zhang, Bin; Cofield, Stacey S; Oparil, Suzanne; Calhoun, David A

    2012-01-01

    Among patients with resistant hypertension (RHTN), there are those whose blood pressure (BP) remains uncontrolled in spite of maximal medical therapy. This retrospective analysis aims to characterize these patients with refractory hypertension. Refractory hypertension was defined as BP that remained uncontrolled after ≥3 visits to a hypertension clinic within a minimum 6-month follow-up period. Of the 304 patients referred for RHTN, 29 (9.5%) remained refractory to treatment. Patients with refractory hypertension and those with controlled RHTN had similar aldosterone levels and plasma renin activity (PRA). Patients with refractory hypertension had higher baseline BP (175±23/97±15 mm Hg vs 158±25/89±15 mm Hg; P=.001/.005) and heart rate, and higher rates of prior stroke and congestive heart failure. During follow-up, the BP of patients with refractory hypertension remained uncontrolled (168.4±14.8/93.8±17.7 mm Hg) in spite of use of an average of 6 antihypertensive medications, while those of patients with controlled RHTN decreased to 129.3±11.2/77.6±10.8 mm Hg. Spironolactone reduced the BP by 12.9±17.8/6.6±13.7 mm Hg in patients with refractory hypertension and by 24.1±16.7/9.2±12.0 mm Hg in patients with controlled RHTN. In patients with RHTN, approximately 10% remain refractory to treatment. Similar aldosterone and PRA levels and a diminished response to spironolactone suggest that aldosterone excess does not explain the treatment failure. © 2011 Wiley Periodicals, Inc.

  16. Oxidative treatment characteristics of biotreated textile-dyeing wastewater and chemical agents used in a textile-dyeing process by advanced oxidation process.

    Science.gov (United States)

    Lim, B R; Hu, H Y; Ahn, K H; Fujie, K

    2004-01-01

    The oxidative treatment characteristics of biotreated textile-dyeing wastewater and typical chemicals such as desizing, scouring, dispersing and swelling agents used in the textile-dyeing process by advanced oxidation process were experimentally studied. The refractory organic matters remained in the effluent of biological treatment process without degradation may be suitable for the improvement of biodegradability and mineralized to CO2 by combined ozonation with and without hydrogen peroxide. On the other hand, the refractory chemicals contained in the scouring agent A and swelling agent may not be mineralized and their biodegradability may not be improved by ozonation. However, the BOD/DOC ratio of scouring agent B increased from 0.3 to 0.45 after ozonation. Based on the results described above, advanced treatment process involving the ozonation without and with the addition of hydrogen peroxide, followed by biological treatment was proposed for the treatment of refractory wastewater discharged from the textile-dyeing process.

  17. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr.; Alireza Rezaie

    2003-12-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesia aluminate and baria aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  18. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Alireza Rezaie

    2003-12-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesia aluminate and baria aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  19. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Alireza Rezaie; Xiaoting Liang; Musa Karakus; Jun Wei

    2005-12-01

    -situ; and were functionally-graded to give the best combination of thermal, mechanical and physical properties and chemical stability; and are relatively inexpensive, reliable repair materials. Material development was divided into 2 tasks: Task 1 was development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO2 and SiC. Task 2 was finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  20. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-10-01

    -situ; and were functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development were divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  1. Refractory for Black Liquor Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick; Musa Karakus; Alireza Rezaie

    2004-03-30

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO2 and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  2. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

    2004-07-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  3. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

    2004-10-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  4. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-01-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  5. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

    2005-04-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  6. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr; Musa Karakus; Xiaoting Liang

    2005-07-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  7. REFRACTORY FOR BLACK LIQUOR GASIFIERS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Headrick Jr.; Alireza Rezaie

    2004-04-01

    surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided into 2 tasks: Task 1, Development and property determinations of improved and existing refractory systems for black liquor containment. Refractory systems of interest include magnesium aluminate and barium aluminate spinels for binder materials, both dry and hydratable, and materials with high alumina contents, 85-95 wt%, aluminum oxide, 5.0-15.0 wt%, and BaO, SrO, CaO, ZrO{sub 2} and SiC. Task 2, Finite element analysis of heat flow and thermal stress/strain in the refractory lining and steel shell of existing and proposed vessel designs. Stress and strain due to thermal and chemical expansion has been observed to be detrimental to the lifespan of existing black liquor gasifiers. The thermal and chemical strain as well as corrosion rates must be accounted for in order to predict the lifetime of the gasifier containment materials.

  8. NASA and ESA Collaboration on Hexavalent Chrome Alternatives - Pretreatments with Primers Screening Final Test Report

    Science.gov (United States)

    Rothgeb, Matthew J.; Kessel, Kurt R.

    2015-01-01

    Hexavalent chromium (hex chrome or Cr(VI)) is a widely used element within applied coating systems because of its self-healing and corrosion-resistant properties. The replacement of hex chrome in the processing of aluminum for aviation and aerospace applications remains a goal of great significance. Aluminum is the major manufacturing material of structures and components in the space flight arena. The National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) are engaged in a collaborative effort to test and evaluate alternatives to hexavalent chromium containing corrosion coating systems. NASA and ESA share common risks related to material obsolescence associated with hexavalent chromium used in corrosion-resistant coatings. In the United States, Occupational Safety and Health Administration (OSHA) studies have concluded that hexavalent chromium is carcinogenic and poses significant risk to human health. On May 5, 2011, amendments to the Defense Federal Acquisition Regulation Supplement (DFARS) were issued in the Federal Register. Subpart 223.73 prohibits contracts from requiring hexavalent chromium in deliverables unless certain exceptions apply. Subpart 252.223-7008 provides the contract clause prohibiting contractors and subcontractors from using or delivering hexavalent chromium in a concentration greater than 0.1 percent by weight for all new contracts associated with supplies, maintenance and repair services, and construction materials. ESA faces its own increasingly stringent regulations within European directives such as Registration, Evaluation, Authorization and Restriction of Chemical (REACH) substances and the Restriction of Hazardous Substances Directive (RoHS) which have set a mid-2017 sunset date for hexavalent chromium. NASA and ESA continue to search for an alternative to hexavalent chromium in coatings applications that meet their performance requirements in corrosion protection, cost, operability, and health and

  9. Refractories for Industrial Processing. Opportunities for Improved Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, James G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hayden, H. Wayne [Metals Manufacture Process and Controls Technology, Inc., Oak Ridge, TN (United States); Angelini, Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Moore, Robert E. [R.E. Moore Associates, Maricopa, AZ (United States); Headrick, William L. [R.E. Moore Associates, Maricopa, AZ (United States)

    2005-01-01

    Refractories are a class of materials of critical importance to manufacturing industries with high-temperature unit processes. This study describes industrial refractory applications and identifies refractory performance barriers to energy efficiency for processing. The report provides recommendations for R&D pathways leading to improved refractories for energy-efficient manufacturing and processing.

  10. Environmentally Friendly Zirconium Oxide Pretreatment

    Science.gov (United States)

    2013-05-01

    Society for Testing and Materials AVCRAD Aviation Classification Repair Activity Depot Chrome (VI) Hexavalent Chromium CRS Cold Rolled Steel...are being used commercially in automotive and other industrial operations as replacements to hexavalent chromium-based and zinc phosphate...application over CRS and aluminum with water-borne and solvent-borne Mil-Spec primers gave results in corrosion performance similar to the chrome

  11. Methods of use of calcium hexa aluminate refractory linings and/or chemical barriers in high alkali or alkaline environments

    Science.gov (United States)

    McGowan, Kenneth A; Cullen, Robert M; Keiser, James R; Hemrick, James G; Meisner, Roberta A

    2013-10-22

    A method for improving the insulating character/and or penetration resistance of a liner in contact with at least one of an alkali and/or alkaline environments is provided. The method comprises lining a surface that is subject to wear by an alkali environment and/or an alkaline environment with a refractory composition comprising a refractory aggregate consisting essentially of a calcium hexa aluminate clinker having the formula CA.sub.6, wherein C is equal to calcium oxide, wherein A is equal to aluminum oxide, and wherein the hexa aluminate clinker has from zero to less than about fifty weight percent C.sub.12A.sub.7, and wherein greater than 98 weight percent of the calcium hexa aluminate clinker having a particle size ranging from -20 microns to +3 millimeters, for forming a liner of the surface. This method improves the insulating character/and or penetration resistance of the liner.

  12. Pack cementation diffusion coatings for Fe-base and refractory alloys. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, R.A. [Ohio State Univ., Columbus, OH (United States). Dept. of Materials Science and Engineering

    1998-03-10

    With the aid of computer-assisted calculations of the equilibrium vapor pressures in halide-activated cementation packs, processing conditions have been identified and experimentally verified for the codeposition of two or more alloying elements in a diffusion coating on a variety of steels and refractory metal alloys. A new comprehensive theory to treat the multi-component thermodynamic equilibria in the gas phase for several coexisting solid phases was developed and used. Many different processes to deposit various types of coatings on several types of steels were developed: Cr-Si codeposition for low- or medium-carbon steels, Cr-Al codeposition on low-carbon steels to yield either a Kanthal-type composition (Fe-25Cr-4Al in wt.%) or else a (Fe, Cr){sub 3}Al surface composition. An Fe{sub 3}Al substrate was aluminized to achieve an FeAl surface composition, and boron was also added to ductilize the coating. The developmental Cr-lean ORNL alloys with exceptional creep resistance were Cr-Al coated to achieve excellent oxidation resistance. Alloy wires of Ni-base were aluminized to provide an average composition of Ni{sub 3}Al for use as welding rods. Several different refractory metal alloys based on Cr-Cr{sub 2}Nb have been silicided, also with germanium additions, to provide excellent oxidation resistance. A couple of developmental Cr-Zr alloys were similarly coated and tested.

  13. Modeling of High Temperature Oxidation Behavior of FeCrAl Alloy by using Artificial Neural Network

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Joon; Ryu, Ho Jin [KAIST, Daejeon (Korea, Republic of)

    2016-10-15

    Refractory alloys are candidate materials for replacing current zirconium-base cladding of light water reactors and they retain significant creep resistance and mechanical strength at high temperatures up to 1500 ℃ due to their high melting temperature. Thermal neutron cross sections of refractory metals are higher than that of zirconium, however the loss of neutron can be overcome by reducing cladding thickness which can be facilitated with enhanced mechanical properties. However, most refractory metals show the poor oxidation resistance at a high temperature. Oxidation behaviors of the various compositions of FeCrAl alloys in high temperature conditions were modeled by using Bayesian neural network. The automatic relevance determination (ARD) technique represented the influence of the composition of alloying elements on the oxidation resistance of FeCrAl alloys. This model can be utilized to understand the tendency of oxidation behavior along the composition of each element and prove the applicability of neural network modeling for the development of new cladding material of light water reactors.

  14. Tungsten and refractory metals 3, proceedings

    International Nuclear Information System (INIS)

    Bose, A.; Dowding, R.J.

    1996-01-01

    The Third International Conference on Tungsten and Refractory Metals was held in Greater Washington DC at the McLean Hilton, McLean Virginia, on November 15--16, 1995. This meeting was the third in a series of conferences held in the Washington DC area. The first meeting was in 1992 and was entitled ''International Conference on Tungsten and Tungsten Alloys.'' In 1994, the scope of the meeting was expanded to include other refractory metals such as molybdenum, iridium, rhenium, tantalum and niobium. The tremendous success of that meeting was the primary motivation for this Conference. The broader scope (the inclusion of other refractory metals and alloys) of the Conference was kept intact for this meeting. In fact, it was felt that the developments in the technology of these materials required a common forum for the interchange of current research information. The papers presented in this meeting examined the rapid advancements in the technology of refractory metals, with special emphasis on the processing, structure, and properties. Among the properties there was emphasis on both quasi-static and dynamic rates. Another topic that received considerable interest was the area of refractory carbides and tungsten-copper composites. One day of concurrent session was necessary to accommodate all of the presentations

  15. Oxidation of lignin-carbohydrate complex from bamboo with hydrogen peroxide catalyzed by Co(salen

    Directory of Open Access Journals (Sweden)

    Zhou Xue-Fei

    2014-01-01

    Full Text Available The reactivity of salen complexes toward hydrogen peroxide has been long recognized. Co(salen was tested as catalyst for the aqueous oxidation of a refractory lignin-carbohydrate complex (LCC isolated from sweet bamboo (Dendrocalamushamiltonii in the presence of hydrogen peroxide as oxidant. Co(salen catalyzed the reaction of hydrogen peroxide with LCC. From the spectra analyses, lignin units in LCC were undergoing ring-opening, side chain oxidation, demethoxylation, β-O-4 cleavage with Co(salen catalytic oxidation. The degradation was also observed in the carbohydrate of LCC. The investigation on the refractory LCC degradation catalyzed by Co(salen may be an important aspect for environmentally-oriented biomimetic bleaching in pulp and paper industry.

  16. Engineering high power induction plasma unit at BARC for mass synthesis of refractory nano-ceramics

    International Nuclear Information System (INIS)

    Ghorui, S.; Sahasrabudhe, S.N.; Dhamale, G.; Das, A.K.

    2013-01-01

    Atmospheric pressure RF thermal plasma sources are gaining increasing importance for production of high purity novel nano-materials in different high-end technological applications. Inherent electrode-less features of the discharge together with the large volume and high energy density of the produced plasma ensures contamination free process environment and mass production ability. Reported herewith is the development of an indigenous induction plasma system for mass synthesis of nanopowders of refractory ceramic materials. The system has been tested for continuous synthesis of Al 2 O 3 nano-powder at a rate of more than 600 gm per hour and checked for its viability for bulk production of nano-particles of other refractory ceramics like Yttrium oxide and Neodymium Oxide. From collected evidences, the process of formation of the nano-particles is identified as the evaporation and subsequent homogeneous nucleation. Major features observed for alumina are complete conversion into highly spherical nano-sized particles, small particle sizes, very narrow size distribution, highly crystallite nature and mixed phases depending on the zone of collection. For alumina, the particles are found to exhibit a uni-modal distribution with peak near 15 nm

  17. Potential refractory alloy requirements for space nuclear power applications

    International Nuclear Information System (INIS)

    Cooper, R.H. Jr.

    1984-01-01

    In reviewing design requirements for refractory alloys for space nuclear applications, several key points are identified. First, the successful utilization of refractory alloys is considered an enabling requirement for the successful deployment of high efficiency, lightweight, and small space nuclear systems. Second, the recapture of refractory alloy nuclear technology developed in the 1960s and early 1970s appears to be a pacing activity in the successful utilization of refractory alloys. Third, the successful application of refractory alloys for space nuclear applications will present a significant challenge to both the materials and the systems design communities

  18. SUS 321 HTB boiler tubing with fire grained internal surface resistant to steam-induced oxidation

    International Nuclear Information System (INIS)

    Kanero, Takahiro; Minami, Yuusuke; Kodera, Toshihide

    1981-01-01

    Considerable amount of scale is produced by high temperature steam on the austenitic stainless steel tubes used for the superheaters and reheaters of large boilers for power generation. The scale of outer layer separates off due to the thermal stress at the time of starting-up and stopping, and causes the blocking of pipes and the erosion of turbine blades. Following the increase of nuclear power generation, large boilers are used for medium load, accordingly it is expected that the troubles like these increase. In this paper, the manufacturing method and the properties of SUS 321 HTB with fine grain internal surface are reported, which was developed to reduce the rate of growth of scale and to prevent the separation of scale. In order to prevent the separation of scale from austenitic stainless steel tubes, the reduction of scale thickness, surface treatment such as chrome plating, the use of alloys with excellent oxidation resistance, the formation of chrome-rich film rapidly, the heat treatment of cold-worked tubes and so on were carried out. The nitrification of SUS 321 H steel brought about two-phase structure of the fine grain internal surface with excellent oxidation resistance and the rest of coarse grains with high creep strength. (Kako, I.)

  19. Refractories for steel-works

    International Nuclear Information System (INIS)

    Villanova, R.A.; Galant, C.L.; Haas, C.; Rosenbaum, V.

    The routine procedures utilized for quality control of refractory materials used by PIRATINI's steel-works, are presented ' under an objetive and practical maner. The attention of the paper is concentrated upon the following' refractory types with higher consume: silicon-aluminous; aluminous; basic magnesia; basic chrom-magnesia. All steps of utilization are described, including specification, supplies programation, storage; sampling; physical tests, and also aplication procedures. Results from routine analysis during a six month period, by ' means of X-Ray Quantometry, using the fusion pearls procedure, are presented compared with Atomic Absorption [pt

  20. Development of AZS refractories for the glass industry

    International Nuclear Information System (INIS)

    Guzman, A.M.; Rodriguez, P.

    2004-01-01

    Refractory materials can support high temperatures, thermal strength and the contact with aggressive environments, for this reason they are widely used in the cement, glass and steel industry. Commercial AZS (alumina-zirconia-silica) refractories are a good alternative in refractory materials for the glass industry' because they can support the aggressive conditions during liquid processing of glass. However, another problem encountered in glass industry is contamination by refractory' material that fall into the molten glass, which can produce a series of defects in the final product. This research was conducted to develop new formulations of AZS refractories with different amounts of ZrO 2 with the purpose of improving the characteristics, properties and the work conditions in the glass melting furnaces and, at the same time, lower the costs this type of refractories. The results obtained indicate that the composition with low content of ZrO 2 can provide better properties than the commercial product, with some modifications in the particle size distribution. Copyright (2004) AD-TECH - International Foundation for the Advancement of Technology Ltd

  1. Refractory migraine in a headache clinic population

    Directory of Open Access Journals (Sweden)

    Fernandez-Torron Roberto

    2011-08-01

    Full Text Available Abstract Background Many migraineurs who seek care in headache clinics are refractory to treatment, despite advances in headache therapies. Epidemiology is poorly characterized, because diagnostic criteria for refractory migraine were not available until recently. We aimed to determine the frequency of refractory migraine in patients attended in the Headache Unit in a tertiary care center, according to recently proposed criteria. Methods The study population consisted of a consecutive sample of 370 patients (60.8% females with a mean age of 43 years (range 14-86 evaluated for the first time in our headache unit over a one-year period (between October 2008 and October 2009. We recorded information on clinical features, previous treatments, Migraine Disability Assessment Score (MIDAS, and final diagnosis. Results Overall migraine and tension-type headache were found in 46.4% and 20.5% of patients, respectively. Refractory migraine was found in 5.1% of patients. In refractory migraineurs, the mean MIDAS score was 96, and 36.8% were medication-overusers. Conclusions Refractory migraine is a relatively common and very disabling condition between the patients attended in a headache unit. The proposed operational criteria may be useful in identifying those patients who require care in headache units, the selection of candidates for combinations of prophylactic drugs or invasive treatments such as neurostimulation, but also to facilitate clinical studies in this patient group.

  2. NOvel Refractory Materials for High Alkali, High Temperature Environments

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, J.G.; Griffin, R. (MINTEQ International, Inc.)

    2011-08-30

    Refractory materials can be limited in their application by many factors including chemical reactions between the service environment and the refractory material, mechanical degradation of the refractory material by the service environment, temperature limitations on the use of a particular refractory material, and the inability to install or repair the refractory material in a cost effective manner or while the vessel was in service. The objective of this project was to address the need for new innovative refractory compositions by developing a family of novel MgO-Al2O3 spinel or other similar magnesia/alumina containing unshaped refractory composition (castables, gunnables, shotcretes, etc) utilizing new aggregate materials, bond systems, protective coatings, and phase formation techniques (in-situ phase formation, altered conversion temperatures, accelerated reactions, etc). This family of refractory compositions would then be tailored for use in high-temperature, highalkaline industrial environments like those found in the aluminum, chemical, forest products, glass, and steel industries. A research team was formed to carry out the proposed work led by Oak Ridge National Laboratory (ORNL) and was comprised of the academic institution Missouri University of Science and Technology (MS&T), and the industrial company MINTEQ International, Inc. (MINTEQ), along with representatives from the aluminum, chemical, glass, and forest products industries. The two goals of this project were to produce novel refractory compositions which will allow for improved energy efficiency and to develop new refractory application techniques which would improve the speed of installation. Also methods of hot installation were sought which would allow for hot repairs and on-line maintenance leading to reduced process downtimes and eliminating the need to cool and reheat process vessels.

  3. SINTERED REFRACTORY TUNGSTEN ALLOYS. Gesinterte hochschmelzende wolframlegierungen

    Energy Technology Data Exchange (ETDEWEB)

    Kieffer, R.; Sedlatschek, K.; Braun, H.

    1971-12-15

    Dependence of the melting point of the refractory metals on their positions in the periodic system - alloys of tungsten with other refractory metals - sintering of the alloys - processing of the alloys - technological properties.

  4. Electrolysis with diamond anodes: Eventually, there are refractory species!

    Science.gov (United States)

    Mena, Ismael F; Cotillas, Salvador; Díaz, Elena; Sáez, Cristina; Rodríguez, Juan J; Cañizares, P; Mohedano, Ángel F; Rodrigo, Manuel A

    2018-03-01

    In this work, synthetic wastewater polluted with ionic liquid 1-butyl-3-methylimidazolium (Bmim) bis(trifluoromethanesulfonyl)imide (NTf 2 ) undergoes four electrolytic treatments with diamond anodes (bare electrolysis, electrolysis enhanced with peroxosulfate promoters, irradiated with UV light and with US) and results obtained were compared with those obtained with the application of Catalytic Wet Peroxide Oxidation (CWPO). Despite its complex heterocyclic structure, Bmim + cation is successfully depleted with the five technologies tested, being transformed into intermediates that eventually can be mineralized. Photoelectrolysis attained the lowest concentration of intermediates, while CWPO is the technology less efficient in their degradation. However, the most surprising result is that concentration of NTf 2 - anion does not change during the five advanced oxidation processes tested, pointing out its strong refractory character, being the first species that exhibits this character in wastewater undergoing electrolysis with diamond. This means that the hydroxyl and sulfate radicals mediated oxidation and the direct electrolysis are inefficient for breaking the C-S, C-F and S-N bounds of the NTf 2 - anion, which is a very interesting mechanistic information to understand the complex processes undergone in electrolysis with diamond. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. A comparative analysis of five chrome green pigments based on different spectroscopic techniques

    International Nuclear Information System (INIS)

    Desnica, V.; Furic, K.; Hochleitner, B.; Mantler, M.

    2003-01-01

    A detailed study of five chrome-based green pigments belonging to a large pigment collection at the Academy of Fine Arts in Vienna, Austria has been performed. The samples were analyzed and compared using the two X-ray methods--X-ray fluorescence and X-ray diffraction, and the two optical methods--Raman spectroscopy and infrared spectroscopy. The composition differences between the similarly denoted samples of the collection were determined and the significant sensitivity differences of the investigated methods to specific compounds have been established. This relative discrepancy of the obtained results depending on the technique used proved once again the need of a combined use of the investigated methods

  6. Stochastic histories of refractory interstellar dust

    International Nuclear Information System (INIS)

    Liffman, K.; Chayton, D.D.

    1988-01-01

    The authors calculate histories for refractory dust particles in the interstellar medium. The double purposes are to learn something of the properties of interstellar dust as a system and to evaluate with specific assumptions the cosmic chemical memory interpretation of a specific class of isotopic anomalies. They assemble the profile of a particle population from a large number of stochastic, or Monte Carlo, histories of single particles, which are necessarily taken to be independent with this approach. They specify probabilities for each of the events that may befall a given particle and unfold its history by a sequence of random numbers. They assume that refractory particles are created only by thermal condensation within stellar material during its ejection from stars, and that these refractory particles can be destroyed only by being sputtered to a size too small for stability or by being incorporated into the formation of new stars. In order to record chemical detail, the authors take each new refractory particle to consist of a superrefractory core plus a more massive refractory mantle. They demonstrate that these superrefractory cores have effective lifetimes much longer than the turnover time of dust mass against sputtering. As examples of cosmic chemical memory they evaluate the 16 O-richness of interstellar aluminum and mechanisms for the 48 Ca/ 50 Ti correlation. Several related consequences of this approach are discussed

  7. High density thoria-silica-metal (III) oxide fibers

    International Nuclear Information System (INIS)

    1974-01-01

    Transparent refractory fibers, at least 50% thoria and additionally containing silica and metal(III) oxides, particularly Al 2 O 3 and B 2 O 3 or Cr 2 O 3 are made by shaping and dehydratively gelling, particularly by extruding in air, viscous aqueous thoria solutions or sols containing colloidal silica with boric acid-stabilized aluminum acetate, or additionally chromium acetate or colloidal Cr 2 O 3 , and heating the resulting gelled fibers in a controlled manner to decompose and volatilize undesired constituents and convert fibers to refractory fibers which are useful to form, for example, refractory fabrics, or as reinforcement for composites. The fabrics are heat resistant. A special application is X-ray protective clothing

  8. Response properties of the refractory auditory nerve fiber.

    Science.gov (United States)

    Miller, C A; Abbas, P J; Robinson, B K

    2001-09-01

    The refractory characteristics of auditory nerve fibers limit their ability to accurately encode temporal information. Therefore, they are relevant to the design of cochlear prostheses. It is also possible that the refractory property could be exploited by prosthetic devices to improve information transfer, as refractoriness may enhance the nerve's stochastic properties. Furthermore, refractory data are needed for the development of accurate computational models of auditory nerve fibers. We applied a two-pulse forward-masking paradigm to a feline model of the human auditory nerve to assess refractory properties of single fibers. Each fiber was driven to refractoriness by a single (masker) current pulse delivered intracochlearly. Properties of firing efficiency, latency, jitter, spike amplitude, and relative spread (a measure of dynamic range and stochasticity) were examined by exciting fibers with a second (probe) pulse and systematically varying the masker-probe interval (MPI). Responses to monophasic cathodic current pulses were analyzed. We estimated the mean absolute refractory period to be about 330 micros and the mean recovery time constant to be about 410 micros. A significant proportion of fibers (13 of 34) responded to the probe pulse with MPIs as short as 500 micros. Spike amplitude decreased with decreasing MPI, a finding relevant to the development of computational nerve-fiber models, interpretation of gross evoked potentials, and models of more central neural processing. A small mean decrement in spike jitter was noted at small MPI values. Some trends (such as spike latency-vs-MPI) varied across fibers, suggesting that sites of excitation varied across fibers. Relative spread was found to increase with decreasing MPI values, providing direct evidence that stochastic properties of fibers are altered under conditions of refractoriness.

  9. Refractory alloy technology for space nuclear power applications

    International Nuclear Information System (INIS)

    Cooper, R.H. Jr.; Hoffman, E.E.

    1984-01-01

    Purpose of this symposium is twofold: (1) to review and document the status of refractory alloy technology for structural and fuel-cladding applications in space nuclear power systems, and (2) to identify and document the refractory alloy research and development needs for the SP-100 Program in both the short and the long term. In this symposium, an effort was made to recapture the space reactor refractory alloy technology that was cut off in midstream around 1973 when the national space nuclear reactor program began in the early 1960s, was terminated. The six technical areas covered in the program are compatibility, processing and production, welding and component fabrication, mechanical and physical properties, effects of irradiation, and machinability. The refractory alloys considered are niobium, molybdenum, tantalum, and tungsten. Thirteen of the 14 pages have been abstracted separately. The remaining paper summarizes key needs for further R and D on refractory alloys

  10. Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers.

    Science.gov (United States)

    Goldoni, Matteo; Caglieri, Andrea; Poli, Diana; Vettori, Maria Vittoria; Corradi, Massimo; Apostoli, Pietro; Mutti, Antonio

    2006-03-15

    Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers.Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively.The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC.Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI).

  11. Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers

    International Nuclear Information System (INIS)

    Goldoni, Matteo; Caglieri, Andrea; Poli, Diana; Vettori, Maria Vittoria; Corradi, Massimo; Apostoli, Pietro; Mutti, Antonio

    2006-01-01

    Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers. Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively. The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC. Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI)

  12. Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers

    Energy Technology Data Exchange (ETDEWEB)

    Goldoni, Matteo [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Caglieri, Andrea [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); Poli, Diana [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Vettori, Maria Vittoria [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Corradi, Massimo [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy); National Institute of Occupational Safety and Prevention, Research Centre at University of Parma, Parma (Italy); Apostoli, Pietro [Laboratory of Industrial Hygiene, Department of Experimental and Applied Medicine, University of Brescia (Italy); Mutti, Antonio [Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Via Gramsci 14, 43100 Parma (Italy)]. E-mail: antonio.mutti@unipr.it

    2006-03-15

    Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers. Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively. The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC. Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI)

  13. REFRACTORY THROMBOCYTOPENIA AND NEUTROPENIA: A DIAGNOSTIC CHALLENGE

    Directory of Open Access Journals (Sweden)

    Emmanuel Gyan

    2015-02-01

    Full Text Available Background. The 2008 WHO classification identified refractory cytopenia with unilineage dysplasia (RCUD as a composite entity encompassing refractory anemia, refractory thrombocytopenia (RT, and refractory neutropenia (RN, characterized by 10% or more dysplastic cells in the bone marrow respective lineage. The diagnosis of RT and RN is complicated by several factors.  Diagnosing RT first requires exclusion of familial thrombocytopenia, chronic auto-immune thrombocytopenia, concomitant medications, viral infections, or hypersplenism. Diagnosis of RN should also be made after ruling out differential diagnoses such as ethnic or familial neutropenia, as well as acquired, drug-induced, infection-related or malignancy-related neutropenia. An accurate quantification of dysplasia should be performed in order to distinguish RT or RN from the provisional entity named idiopathic cytopenia of unknown significance (ICUS. Cytogenetic analysis, and possibly in the future somatic mutation analysis (of genes most frequently mutated in MDS, and flow cytometry analysis aberrant antigen expression on myeloid cells may help in this differential diagnosis. Importantly, we and others found that, while isolated neutropenia and thrombocytopenia are not rare in MDS, those patients can generally be classified (according to WHO 2008 classification as refractory cytopenia with multilineage dysplasia or refractory anemia with excess blasts, while RT and RN (according to WHO 2008 are quite rare.These results suggest in particular that identification of RT and RN as distinct entities could be reconsidered in future WHO classification updates.

  14. An evaluation of electric melter refractories for contact with glass used for the immobilisation of nuclear waste

    International Nuclear Information System (INIS)

    Hayward, P.J.; George, I.M.

    1987-01-01

    Corrosion tests have been performed on twelve candidate refractories in contact with borosilicate, titanosilicate, and aluminosilicate melts, in order to rank them for use in an all-electric melter for the production of waste form materials suitable for immobilising nuclear fuel recycle wastes. Viscosities and electrical conductivities of the melts have also been measured to enable optimum processing conditions to be determined. Of the materials tested, the choice of glass contact refractory for the Joule heated melting of the borosilicate and titanosilicate compositions is Monofrax K3 or SEPR 2161, in conjunction with tin oxide electrodes. The aluminosilicate glass waste form would require an alternative method of production (sol-gel processing, or sintering of a precursor frit), because of its high viscosity. (author)

  15. 154 Effet du chrome niacinate sur la tolérance au glucose chez le rat ...

    African Journals Online (AJOL)

    PR BOKO

    contribution to the DEX treated groups. CrN supplementation did not correct the elevation of blood glucose ... chrome niacinate (30mg/kg/j, PO) pendant 14 jours, n=10. 2-2-2. Prélèvements. 1mL de sang a été prélevé à partir de la veine caudale sur tube hépariné à j0, j7, j14, j21 et j28. Les prélèvements ont été centrifugés ...

  16. Elevated Frequencies of Micronuclei and other Nuclear Abnormalities of Chrome Plating Workers Occupationally Exposed to Hexavalent Chromium

    OpenAIRE

    Sudha, S; Kripa, SK; Shibily, P; Shyn, J

    2011-01-01

    Background Biomonitoring provides a useful tool to estimate the genetic risk from exposure to genotoxic agents. The aim of this study was to assess the potential cytogenetic damage associated with occupational exposure to hexavalent chromium by using micronuclei (MN) as a biomarker. Methods This was a cross-sectional study and all participants were males. Both the exposed and control individuals were selected from Coimbatore, Southern India. Exfoliated buccal cells from 44 chrome plating work...

  17. ESR investigations of radiation grafting of methyl methacrylate in aqueous emulsion onto chrome-tanned pig skin

    International Nuclear Information System (INIS)

    Pietrucha, K.; Pekala, W.; Plonka, A.

    1980-01-01

    Upon γ-irradiation at 77 K of the aqueous emulsions of methyl methacrylate embedded into chrome-tanned pig skins there are formed only the radicals of collagen and of 2-el-2-methylopropionic acid methyl ester. The presence of water in the system increases markedly the radiation yield of collagen radicals. During gradual heating up the polymerization reactions start and the macro-radical of growing polymer is observed. Chromium does not participate in the processes of initiation and grafting. (author)

  18. Refractory alloy technology for space nuclear power applications

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.H. Jr.; Hoffman, E.E. (eds.)

    1984-01-01

    Purpose of this symposium is twofold: (1) to review and document the status of refractory alloy technology for structural and fuel-cladding applications in space nuclear power systems, and (2) to identify and document the refractory alloy research and development needs for the SP-100 Program in both the short and the long term. In this symposium, an effort was made to recapture the space reactor refractory alloy technology that was cut off in midstream around 1973 when the national space nuclear reactor program began in the early 1960s, was terminated. The six technical areas covered in the program are compatibility, processing and production, welding and component fabrication, mechanical and physical properties, effects of irradiation, and machinability. The refractory alloys considered are niobium, molybdenum, tantalum, and tungsten. Thirteen of the 14 pages have been abstracted separately. The remaining paper summarizes key needs for further R and D on refractory alloys. (DLC)

  19. Hardening parts by chrome plating in manufacture and repair

    Science.gov (United States)

    Astanin, V. K.; Pukhov, E. V.; Stekolnikov, Y. A.; Emtsev, V. V.; Golikova, O. A.

    2018-03-01

    In the engineering industry, galvanic coatings are widely used to prolong the service life of the machines, which contribute to the increase in the strength of the parts and their resistance to environmental influences, temperature and pressure drops, wear and fretting corrosion. Galvanic coatings have been widely applied in engineering, including agriculture, aircraft building, mining, construction, and electronics. The article focuses on the manufacturing methods of new agricultural machinery parts and the repair techniques of worn parts by chrome plating. The main attention is paid to the unstable methods of chromium deposition (in pulsed and reversing modes) in low-concentration electrolytes, which makes it possible to increase the reliability and durability of the hardened parts operation by changing the conditions of electrocrystallization, that is, directed formation of the structure and texture, thickness, roughness and microhardness of chromium plating. The practical recommendations are given on the current and temperature regimes of chromium deposition and composition of baths used for the restoration and hardening of the machine parts. Moreover, the basic methods of machining allowances removal are analysed.

  20. Temperature and Thermal Stress Analysis of Refractory Products

    Directory of Open Access Journals (Sweden)

    Shaoyang Shi

    2013-05-01

    Full Text Available Firstly current status of temperature and thermal stress research of refractory product at home and aboard are analyzed. Finite element model of two classical refractory products is building by using APDL language. Distribution law of temperature and thermal stress of two typical refractory products-ladles and tundish are analyzed and their structures are optimized. Stress of optimal structure is dropped obviously, and operation life is increased effectively.

  1. Kinetic model of the thermal pyrolysis of chrome tanned leather treated with NaOH under different conditions using thermogravimetric analysis.

    Science.gov (United States)

    Bañón, E; Marcilla, A; García, A N; Martínez, P; León, M

    2016-02-01

    The thermal decomposition of chrome tanned leather before and after a soaking treatment with NaOH was studied using thermogravimetric analysis (TGA). The effect of the solution concentration (0.2M and 0.5M) and the soaking time (5min and 15min) was evaluated. TGA experiments at four heating rates (5, 10, 15 and 20°Cmin(-1)) were run in a nitrogen atmosphere for every treatment condition. A kinetic model was developed considering the effect of the three variables studied, i.e.: the NaOH solution concentration, the soaking time and the heating rate. The proposed model for chrome tanned leather pyrolysis involves a set of four reactions, i.e.: three independent nth order reactions, yielding the corresponding products and one of them undergoing a successive cero order reaction. The model was successfully applied simultaneously to all the experimental data obtained. The evaluation of the kinetic parameters obtained (activation energy, pre-exponential factor and reaction order) allowed a better understanding of the effect of the alkali treatment on these wastes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. SiC as an oxidation-resistant refractory material. Pt. 1

    International Nuclear Information System (INIS)

    Schlichting, J.

    1979-01-01

    Uses his own investigations and gives a literature survey on the oxidation and corrosion behaviour of SiC (in the form of a pure SiC powder, hot-pressed and reaction-sintered materials). The excellent stability of SiC in oxidizing atmosphere is due to the development of protective SiO 2 coatings. Any changes in these protective coatings (e.g. due to impurities with corrosive media, high porosity of SiC, etc.) lead in most cases to increased rates of oxidation and thus restrict the field of application of SiC. (orig.) [de

  3. Recycling of Chrome Tanned Leather Dust in Acrylonitrile Butadiene Rubber

    Science.gov (United States)

    El-Sabbagh, Salwa H.; Mohamed, Ola A.

    2010-06-01

    Concerns on environmental waste problem caused by chrome tanned leather wastes in huge amount have caused an increasing interest in developing this wastes in many composite formation. This leather dust was used as filler in acrylonitrile butadiene rubber (NBR) before treatment and after treatment with ammonia solution and sod. formate. Different formulations of NBR/ leather dust (untreated-treated with ammonia solution—treated with sod. formate) composites are prepared. The formed composite exhibit a considerable improvement in some of their properties such as rheometric characteristics especially with composites loaded with treated leather dust. Tensile strength, modulus at 100% elongation, hardness and youngs modulus were improved then by further loading start to be steady or decrease. Cross linking density in toluene were increased by incorporation of leather dust treated or untreated resulting in decreases in equilibrium swelling. Distinct increase in the ageing coefficient of both treated and untreated leather with drop in NBR vulcanizates without leather dust. Addition of leather dust treated or untreated exhibit better thermal stability.

  4. Comparative evaluation of the locally manufactured low-alumina fireclay refractories

    International Nuclear Information System (INIS)

    Mohammad, D.; Ahmed, W.; Khan, M.I.

    2007-01-01

    Properties of domestically produced low-alumina refractories commonly known as medium duty fireclay refractories were studied and a comparative evaluation was performed. Refractory properties such as density, porosity, cold strength, reheat change and deformation at high-temperature were determined. Significant differences were discovered between these products sold as medium duty fireclay refractories. One brand marketed as medium duty refractory was found to be too inferior to be designated as medium duty firebrick. Absence of any standards and lack of awareness on the part of users of the various test methods appear to be the cause of this situation. (author)

  5. Directed light fabrication of refractory metals and alloys

    International Nuclear Information System (INIS)

    Fonseca, J.C.; Lewis, G.K.; Dickerson, P.G.; Nemec, R.B.

    1999-01-01

    This report covers deposition of refractory pure metals and alloys using the Directed Light Fabrication (DLF) process and represents progress in depositing these materials through September 1998. In extending the DLF process technology to refractory metals for producing fully dense, structurally sound deposits, several problems have become evident. (1) Control of porosity in DLF-deposited refractory metal is difficult because of gases, apparently present in commercially purchased refractory metal powder starting materials. (2) The radiant heat from the molten pool during deposition melts the DLF powder feed nozzle. (3) The high reflectivity of molten refractory metals, at the Nd-YAG laser wavelength (1.06microm), produces damaging back reflections to the optical train and fiber optic delivery system that can terminate DLF processing. (4) The current limits on the maximum available laser power to prevent back reflection damage limit the parameter range available for densification of refractory metals. The work to date concentrated on niobium, W-25Re, and spherodized tungsten. Niobium samples, made from hydride-dehydride powder, had minimal gas porosity and the deposition parameters were optimized; however, test plates were not made at this time. W-25Re samples, containing sodium and potassium from a precipitation process, were made and porosity was a problem for all samples although minimized with some process parameters. Deposits made from potassium reduced tungsten that was plasma spherodized were made with minimized porosity. Results of this work indicate that further gas analysis of starting powders and de-gassing of starting powders and/or gas removal during deposition of refractory metals is required

  6. The influence of activating agents on the performance of rice husk-based carbon for sodium lauryl sulfate and chrome (Cr) metal adsorptions

    Science.gov (United States)

    Arneli; Safitri, Z. F.; Pangestika, A. W.; Fauziah, F.; Wahyuningrum, V. N.; Astuti, Y.

    2017-02-01

    This research aims to study the influence of activating agents to produce rice husk based-carbon with high adsorption capacity and efficiency for either hazardous organic molecules or heavy metals which are unfriendly for the environment. Firstly, rice husk was burned by pyrolysis at different temperatures to produce rice husk-based carbon. To improve its ability as an adsorbent, carbon was treated with activating agents, namely, H3PO4 and KOH at room and high temperature (420 °C). The performance of carbon was then tested by contacting it with surfactant (SLS). Finally, the surfactant-modified active carbon was applied for chrome metal removal. The result shows that activation of carbon using phosphate acid (H3PO4) was more effective than potassium hydroxide (KOH) conducted at high temperature to adsorb sodium lauryl sulfate (SLS) and chrome metal with the adsorption capacity 1.50 mgg-1 and 0.375 mgg-1, respectively.

  7. Machining refractory alloys: an overview

    International Nuclear Information System (INIS)

    Christopher, J.D.

    1984-01-01

    Nontraditional machining is a generic term for those material removal processes that differ drastically from the historic operations such as turning, milling, drilling, tapping, and grinding. The use of primary energy modes other than mechanical, such as thermal, electrical, and chemical, sets these operations apart and reinforces their nontraditional label. Several of these newer processes have been very successful in machining close tolerance parts from refractory materials. This paper provides a general overview of both traditional and nontraditional aspects of machining refractory materials. 11 figures, 7 tables

  8. The Effects of Mg/Si on the Exoplanetary Refractory Oxygen Budget

    Science.gov (United States)

    Unterborn, Cayman T.; Panero, Wendy R.

    2017-08-01

    Solar photospheric abundances of refractory elements mirror the Earth’s to within ˜10 mol% when normalized to the dominant terrestrial-planet-forming elements Mg, Si, and Fe. This allows for the adoption of solar composition as an order-of-magnitude proxy for Earth’s. It is not known, however, the degree to which this mirroring of stellar and terrestrial planet abundances holds true for other star-planet systems without determination of the composition of initial planetesimals via condensation sequence calculations and post condensation processes. We present the open-source Arbitrary Composition Condensation Sequence calculator (ArCCoS) to assess how the elemental composition of a parent star affects that of the planet-building material, including the extent of oxidation within the planetesimals. We demonstrate the utility of ArCCoS by showing how variations in the abundance of the stellar refractory elements Mg and Si affect the condensation of oxygen, a controlling factor in the relative proportions of planetary core and silicate mantle material. This thereby removes significant degeneracy in the interpretation of the structures of exoplanets, as well as provides observational tests for the validity of this model.

  9. Recursos de información elaborados por el CRAI. Instalar y Configurar Zotero enlazarlo a Mozilla, Chrome y Word

    OpenAIRE

    López Lucas, Jesús

    2018-01-01

    Este tutorial explica los pasos para la instalación del gestor de referencias bibliográficas Zotero en un PC con Sistema Operativo Microsoft Windows. Asimismo, se indican las características del software y la manera de trabajar con él desde Mozilla Firefox, Google Chrome y Microsoft Word. Tutorial sobre instalación y configuración de Zotero para los diferentes navegadores web.

  10. Directed light fabrication of refractory metals and alloys

    International Nuclear Information System (INIS)

    Fonseca, J.C.; Lewis, G.K.; Dickerson, P.G.; Nemec, R.B.

    1999-01-01

    This report covers work performed under Order No. FA0000020 AN Contract DE-AC12-76SN00052 for deposition of refractory pure metals and alloys using the Directed Light Fabrication (DLF) process and represents the progress in depositing these materials through September 1998. In extending the DLF process technology to refractory metals for producing fully dense, structurally sound deposits, several problems have become evident. 1. Control of porosity in DLF-deposited refractory metal is difficult because of gases, apparently present in commercially purchased refractory metal powder starting materials. 2. The radiant heat from the molten pool during deposition melts the DLF powder feed nozzle. 3. The high reflectivity of molten refractory metals, at the Nd-YAG laser wavelength (1.06microm), produces damaging back reflections to the optical train and fiber optic delivery system that can terminate DLF processing. 4. The current limits on the maximum available laser power to prevent back reflection damage limit the parameter range available for densification of refractory metals. The work to date concentrated on niobium, W-25Re, and spherodized tungsten. Niobium samples, made from hydride-dehydride powder, had minimal gas porosity and the deposition parameters were optimized; however, test plates were not made at this time. W-25Re samples, containing sodium and potassium from a precipitation process, were made and porosity was a problem for all samples although minimized with some process parameters. Deposits made from potassium reduced tungsten that was plasma spherodized were made with minimized porosity. Results of this work indicate that further gas analysis of starting powders and de-gassing of starting powders and/or gas removal during deposition of refractory metals is required

  11. Chemical and Electronic Structure Studies of Refractory and Dielectric Thin Films.

    Science.gov (United States)

    Corneille, Jason Stephen

    This study presents the synthesis and characterization of oxide and refractory thin films under varying conditions. The deposition of the thin films is performed under vacuum conditions. The characterization of the growth, as well as the chemical and electronic properties of the thin films was accomplished using a broad array of surface analytical techniques. These model studies describe the relationship between the preparative processes and the stoichiometry, structure and electronic properties of the film products. From these efforts, the optimal deposition conditions for the production of high quality films have been established. The thin film oxides synthesized and studied here include magnesium oxide, silicon oxide and iron oxide. These oxides were synthesized on a refractory substrate using both post oxidation of thin films as well as reactive vapor deposition of the metals in the presence of an oxygen background. Comparisons and contrasts are presented for the various systems. Metallic magnesium films were grown and characterized as a preliminary study to the synthesis of magnesium oxide. Magnesium oxide (MgO(100)) was synthesized on Mo(100) by evaporating magnesium at a rate of one monolayer per minute in an oxygen background pressure of 1 times 10 ^{-6} Torr at room temperature. The resulting film was found to exhibit spectroscopic characteristics quite similar to those observed for bulk MgO. The acid/base characteristics of the films were studied using carbon monoxide, water and methanol as probe molecules. The film was found to exhibit essentially the same chemical properties as found in analogous powdered catalysts. Silicon dioxide was synthesized by evaporating silicon onto Mo(100) in an oxygen ambient. It is shown that the silicon oxide prepared at room temperature with a silicon deposition rate of {~ }{1.2}A/min and an oxygen pressure of 2 times 10^{ -8} Torr, consisted of predominantly silicon dioxide with a small fraction of suboxides. Annealing to

  12. Spinning of refractory metals

    International Nuclear Information System (INIS)

    Chang Wenkua; Zheng Han

    1989-01-01

    The effects of spinning process parameters including max. pass percentage reduction, spinning temperature, feed rate, lubricant and annealing technology on the quality of shaped components are summarized and discussed in the present paper. The above mentioned parameters are adopted in the process of spinning of barrel-shaped and specially shaped components of refractory metals and their alloys W, Mo, Nb, Zr, TZM molybdenum alloy, C-103, C-752 niobium alloy etc. The cause of leading to usual defects of spun products of refractory metals such as lamellar as 'scaling', crack, swelling, wrinkle, etc. have been analysed and the ways to eliminate the defects have been put forward. 8 figs., 5 tabs. (Author)

  13. Migration of TRU-containing slag into candidate refractories for waste management

    International Nuclear Information System (INIS)

    Seymour, W.C.

    1978-11-01

    Results of initial tests on transuranic migration into commercial refractories are reported. Five castable refractories and a plastic-bonded refractory were tested using the cup test method. Initial results indicate that castable materials will not survive conditions expected in the slagging pyrolysis unit; plastic refractories appear to have better performance. The major mechanism of migration into the tested refractories is pore penetration. Al 2 O 3 and Al 2 O 3 -Cr 2 O 3 phases appear resistant to chemical diffusion of transuranics. 2 figures, 16 tables

  14. Development of alumino-silicate refractories in Ghana

    International Nuclear Information System (INIS)

    Kisiedu, A. K.; Tetteh, D.M.B.; Obiri, H. A.; Brenya, E. F.; Ayensu, A.

    2008-01-01

    Alumino-silicate (bauxite), andalusite, kaolin and clay were investigated for suitability in production of alumina, mullite and fireclay brick refractories. The raw materials were characterized by X-ray diffraction, differential thermal and silicate analyses. The x-ray diffraction analysis of alumina and mullite refractories fired at 1450 0 C, and fireclay bricks fired at 1350 0 C, indicated presence of corundum and alpha-alumina crystals. The values of thermal (fired) shrinkage, crushing, strength, porosity, water absorption and bulk density determined were 31.1%, 2.3 x 10 3 kg/m 3 , 4.86 x 10 6 N/m 2 and 13.2 % for mullite; 30.2%, 2.4 x 10 3 kg/m 3 , 3.20 x 10 6 N/m 2 and W = 12.8 % for alumina; and 25.2 %, 2.1 x 10 3 kg/m 3 , 2.61 x 10 6 N/m 2 and W = 11.8% for fireclay, respectively. Bauxite, andalusite and special kaolin were identified as potential raw materials for developing alumina and mullite refractories for construction of high temperature kilns and furnaces operating at 1350 0 C. The clay and kaolin minerals could be used to produce fireclay refractories for construction of incinerators operating at maximum temperatures of about 1000 0 C. The performance of the refractories was demonstrated by producing bricks to construct kilns and incinerators for the ceramic industry and hospitals. (au)

  15. A review of the chrome mordant dyeing of wool with special reference to the afterchrome process

    CSIR Research Space (South Africa)

    Maasdorp, APB

    1983-11-01

    Full Text Available a -~min*o'- Hydroxyaw Dycs Salicylic Acid Dyes Azo dyes oxidkd to Quinone form when complexed (C.I. Mordant Black 3) e Chrome Fast Brow TV (C.I. Mordant Brow 33) Flavine A (C.I. Mordant Yellow 5) e Solochrome Rcd (C.I. Mordant..., it was decided that they should bedescribed in more detail. In 1858, Peter Greiss, a chemist at a Burton-on-Trent brewery produced the first diizonium salts by treating primary aromatic amines with nitrous acid produced from hydrochloric acid and sodium...

  16. Refractory disease in antineutrophil cytoplasmic antibodies associated vasculitis

    NARCIS (Netherlands)

    Rutgers, Abraham; Kallenberg, Cornelis

    Purpose of review Induction treatment of antineutrophil cytoplasmic antibodies (ANCA) associated vasculitis (AAV) is not always successful and nonresponding patients are considered refractory. Recent findings Refractory disease should be subdefined to the treatment that was received.

  17. AN ADVANCED OXIDATION PROCESS : FENTON PROCESS

    Directory of Open Access Journals (Sweden)

    Engin GÜRTEKİN

    2008-03-01

    Full Text Available Biological wastewater treatment is not effective treatment method if raw wastewater contains toxic and refractory organics. Advanced oxidation processes are applied before or after biological treatment for the detoxification and reclamation of this kind of wastewaters. The advanced oxidation processes are based on the formation of powerful hydroxyl radicals. Among advanced oxidation processes Fenton process is one of the most promising methods. Because application of Fenton process is simple and cost effective and also reaction occurs in a short time period. Fenton process is applied for many different proposes. In this study, Fenton process was evaluated as an advanced oxidation process in wastewater treatment.

  18. Diagnosis and management of refractory celiac disease: a systematic review.

    Science.gov (United States)

    Labidi, Asma; Serghini, Meriem; Karoui, Sami; Boubaker, Jalel; Filali, Azza

    2013-01-01

    Refractory celiac disease is defined by persisting malabsorptive symptoms in spite of a strict gluten free diet for at least 6 to 12 months. Alternatives to gluten free diet seem to be still controversial. To describe the clinical and epidemiologic aspects of refractory celiac disease, and to identify therapeutic options in this condition. Systematic review and critical analysis of observational studies, clinical trials and case reports that focused on diagnosis and management of refractory celiac disease. Refractory celiac disease can be classified as type 1 or type 2 according to the phenotype of intraepithelial lymphocytes. Great complications such as enteropathy-associated T-cell lymphoma may occur in a subgroup of these patients mainly in refractory celiac disease type 2. Curative therapies are still lacking. Refractory celiac disease remains a diagnosis of exclusion. Its prognosis remains still dismal by the absence yet of curative therapies. However, some new treatments seem to hold promise during few cohort-studies.

  19. Modern materials based on refractory compounds

    International Nuclear Information System (INIS)

    Kosolapova, T.Ya.

    1979-01-01

    Discussed are the existing methods for synthesizing powders of binary refractory compounds and high-productivity techniques which hold promise as regards the manufacture of highly disperse and pure powders. Plasmochemical synthesis is shown to be an effective method for obtaining practically all carbides, nitrides and borides. A description is given of three main methods for obtaining single crystals of refractory compounds (TiN, TiC, ZrC, ZrB 2 , NbC) fairly perfect in structure and composition. These processes include deposition from vapour-gas phase, melting in arc plasma and crystallization from solutions in metallic melts. The advantages have been shown of the self-propagating high-temperature synthesis of refractory compounds, ensuring the manufacture of products, close in composition to stoichiometric ones simultaneously with forming of items. Mechanical, thermal, abrasive, and resistive characteristics of the above materials are presented

  20. Monitoring the intensity of mechanical vibration during the processing of chrome steel 14109

    Directory of Open Access Journals (Sweden)

    Š. Salokyová

    2017-01-01

    Full Text Available Article deals with the examination of the effect of cutting parameters on the occurrence and size of mechanical vibration on three selected measured points during the processing of chrome steel. It also includes execution, experiment evaluation in this field and comparison of measured vibrations acceleration amplitude values according to the standards. The results of the measurement serve for early identification of a defect, which has great effect on the smoothness and efficiency of the machine. The article concludes with the proposed new findings from the measured values evaluation and formulated new recommendations for the operation in production system with lathe turning technology. The measured experimental values of the acceleration amplitude of mechanical vibrations were compared with theoretical values.

  1. Structure, preparation and properties of refractory compounds and systems

    International Nuclear Information System (INIS)

    Holleck, H.; Thuemmler, F.

    1977-01-01

    At the beginning of this report the possibilities of hardness optimization of refractory carbides are generally discussed. Three papers deal with TaC-basis refractories and hard metals. In particular, carbides with very low nonmetal/metal ratios and composites with hard phases formed by decomposition of tantalum carbonitrides are discussed. Another contribution reports investigations concerning the influence of the microstructure on the hardness of polycristaline mixed carbides. In a series of four papers, results are presented on the work of optimization conventional WC hard metals by introduction of a Fe,Co,Ni-binder: The influence of composition, carbon content and sintering conditions, as well as the wetting behaviour between carbides and binder metals are discussed. Phase relations in the refractory nitride and refractory nitride-binder metal systems as well as phase stabilities of ordered transition metal phases are reported in three papers, fundamental in character. Finally, the work concerning chemical analysis of refractory systems is described. (orig.) [de

  2. Refractory versus resistant hypertension: Novel distinctive phenotypes

    Science.gov (United States)

    Dudenbostel, Tanja; Siddiqui, Mohammed; Gharpure, Nitin; Calhoun, David A.

    2017-01-01

    Resistant hypertension (RHTN) is relatively common with an estimated prevalence of 10-20% of treated hypertensive patients. It is defined as blood pressure (BP) >140/90 mmHg treated with ≥3 antihypertensive medications, including a diuretic, if tolerated. Refractory hypertension is a novel phenotype of severe antihypertensive treatment failure. The proposed definition for refractory hypertension, i.e. BP >140/90 mmHg with use of ≥5 different antihypertensive medications, including a diuretic and a mineralocorticoid receptor antagonist (MRA) has been applied inconsistently. In comparison to RHTN, refractory hypertension seems to be less prevalent than RHTN. This review focuses on current knowledge about this novel phenotype compared with RHTN including definition, prevalence, mechanisms, characteristics and comorbidities, including cardiovascular risk. In patients with RHTN excess fluid retention is thought to be a common mechanism for the development of RHTN. Recently, evidence has emerged suggesting that refractory hypertension may be more of neurogenic etiology due to increased sympathetic activity as opposed to excess fluid retention. Treatment recommendations for RHTN are generally based on use and intensification of diuretic therapy, especially with the combination of a long-acting thiazide-like diuretic and an MRA. Based on findings from available studies, such an approach does not seem to be a successful strategy to control BP in patients with refractory hypertension and effective sympathetic inhibition in such patients, either with medications and/or device based approaches may be needed. PMID:29034321

  3. Forming Refractory Insulation On Copper Wire

    Science.gov (United States)

    Setlock, J.; Roberts, G.

    1995-01-01

    Alternative insulating process forms flexible coat of uncured refractory insulating material on copper wire. Coated wire formed into coil or other complex shape. Wire-coating apparatus forms "green" coat on copper wire. After wire coiled, heating converts "green" coat to refractory electrical insulator. When cured to final brittle form, insulating material withstands temperatures above melting temperature of wire. Process used to make coils for motors, solenoids, and other electrical devices to be operated at high temperatures.

  4. Effects of conducting oxide barrier layers on the stability of Crofer® 22 APU/Ca3Co4O9 interfaces

    DEFF Research Database (Denmark)

    Holgate, Tim C.; Han, Li; Wu, NingYu

    2014-01-01

    Practical implementation of oxide thermoelectrics on an industrial or commercial scale for waste heat energy conversion requires the development of chemically stable interfaces between metal interconnects and oxide thermoelements that exhibit low electrical contact resistances. A commercially...... available high-chrome iron alloy (i.e., Crofer® 22 APU) serving as the interconnect metal was spray coated with LaNi0.6Fe0.4O3 (LNFO) or (Mn,Co)3O4 spinel and then interfaced with a p-type thermoelectric material—calcium cobaltate (Ca3Co4O9)—using spark plasma sintering. The interfaces have been...

  5. High-dose chemotherapy and auto-SCT for relapsed and refractory Hodgkin's lymphoma patients refractory to first-line salvage chemotherapy but responsive to second-line salvage chemotherapy.

    Science.gov (United States)

    Rauf, Muhammad Shahzad; Maghfoor, Irfan; Elhassan, Tusneem Ahmed M; Akhtar, Saad

    2015-01-01

    Relapsed or primary refractory Hodgkin's lymphoma (HL) patients refractory to first-line salvage chemotherapy (first salvage) and unable to undergo high-dose chemotherapy (HDC) and autologous stem cell transplant (auto-SCT) have very poor outcome. Some patients are offered second-line salvage chemotherapy (second salvage), if they are responsive and may receive HDC auto-SCT. We identified 31 patients (18 males, 13 females) from 1996-2012 who received second salvage prior to auto-SCT. Median age at auto-SCT is 22 years. Patients were grouped as (1) relapsed-refractory (Rel:Ref): patients with prior complete response (CR) and on relapse found refractory to first salvage and received second salvage and (2) refractory-refractory (Ref:Ref): patients refractory to both primary treatment and first salvage and received second salvage. Median follow-up is 63 months (18-170). Disease status after second salvage prior to HDC was CR 16 %, partial response (PR) 71 % and stable disease 13 %. After HDC auto-SCT, CR:PR: progressive disease was observed in 18 (58 %): four (12 %): nine (29 %) patients, respectively. Five-year overall survival (OS) for whole group is 57 % (Rel:Ref vs. Ref:Ref, 73 % vs. 48 %, p = 0.48). Progression-free survival (PFS) for whole group is 52 % (Rel:Ref vs. Ref:Ref, 73 % vs. 40 % respectively, p = 0.11). Second-line salvage is a valid approach with no long-term side effects for those HL patients who do not respond to first-line salvage chemotherapy and they can be candidate of HDC and stem cell transplant with a high ORR, the PFS and OS in relapse-refractory and refractory-refractory group of patients.

  6. Characterization of arsenic resistant and arsenopyrite oxidizing Acidithiobacillus ferrooxidans from Hutti gold leachate and effluents.

    Science.gov (United States)

    Dave, Shailesh R; Gupta, Kajal H; Tipre, Devayani R

    2008-11-01

    Four arsenic resistant ferrous oxidizers were isolated from Hutti Gold Mine Ltd. (HGML) samples. Characterization of these isolates was done using conventional microbiological, biochemical and molecular methods. The ferrous oxidation rates with these isolates were 16, 48, 34 and 34 mg L(-1)h(-1) and 15, 47, 34 and 32 mg L(-1)h(-1) in absence and presence of 20 mM of arsenite (As3+) respectively. Except isolate HGM 8, other three isolates showed 2.9-6.3% inhibition due to the presence of 20 mM arsenite. Isolate HGM 8 was able to grow in presence of 14.7 g L(-1) of arsenite, with 25.77 mg L(-1)h(-1) ferrous oxidation rate. All the four isolates were able to oxidize iron and arsenopyrite from 20 g L(-1) and 40 g L(-1) refractory gold ore and 20 g L(-1) refractory gold concentrate. Once the growth was established pH adjustment was not needed inspite of ferrous oxidation, which could be due to concurrent oxidation of pyrite. Isolate HGM 8 showed the final cell count of as high as 1.12 x 10(8) cells mL(-1) in 40 g L(-1) refractory gold ore. The isolates were grouped into one haplotypes by amplified ribosomal DNA restriction analysis (ARDRA). The phylogenetic position of HGM 8 was determined by 16S rDNA sequencing. It was identified as Acidithiobacillus ferrooxidans and strain name was given as SRHGM 1.

  7. Refractory myasthenia gravis - clinical profile, comorbidities and response to rituximab.

    Science.gov (United States)

    Sudulagunta, Sreenivasa Rao; Sepehrar, Mona; Sodalagunta, Mahesh Babu; Settikere Nataraju, Aravinda; Bangalore Raja, Shiva Kumar; Sathyanarayana, Deepak; Gummadi, Siddharth; Burra, Hemanth Kumar

    2016-01-01

    Introduction: Myasthenia gravis (MG) is an antibody mediated autoimmune neuromuscular disorder characterized by fatigable muscle weakness. A proportion of myasthenia gravis patients are classified as refractory due to non responsiveness to conventional treatment. This retrospective study was done to evaluate clinical profile, epidemiological, laboratory, and features of patients with MG and mode of management using rituximab and complications. Methods: Data of myasthenia gravis patients admitted or presented to outpatient department (previous medical records) with MG between January 2008 and January 2016 were included. A total of 512 patients fulfilled the clinical and diagnostic criteria of myasthenia gravis of which 76 patients met the diagnostic certainty for refractory myasthenia gravis and were evaluated. Results: Out of 76 refractory MG patients, 53 (69.73%) patients fulfilled all the three defined criteria. The median age of onset of the refractory MG group was 36 years with a range of 27-53 years. In our study 25 patients (32.89%) belonged to the age group of 21-30 years. Anti-MuSK antibodies were positive in 8 non-refractory MG patients (2.06%) and 36 refractory MG patients (47.36%). Mean HbA 1C was found to be 8.6±2.33. The dose of administered prednisone decreased by a mean of 59.7% ( p =3.3x10 -8 ) to 94.6% ( p =2.2x10 -14 ) after the third cycle of rituximab treatment. Conclusion: The refractory MG patients are most commonly female with an early age of onset, anti-MuSK antibodies, and thymomas. Refractory MG patients have higher prevalence and poor control (HbA 1C >8%) of diabetes mellitus and dyslipidemia probably due to increased steroid usage. Rituximab is very efficient in treatment of refractory MG with adverse effects being low.

  8. RESULTS OF OUTPATIENT PROGRAM ON EFFECTIVE THERAPY OF REFRACTORY ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    M. M. Batyushin

    2015-12-01

    Full Text Available Aim. To increase in efficacy of antihypertensive therapy in patients with refractory arterial hypertension (HT.Material and methods. Patients with refractory HT were revealed during first month of program. The causes of refractory HT were analyzed. Combined antihypertensive therapy was prescribed to reach target level of blood pressure (BP. This therapy lasted 24 weeks and included angiotensin converting enzyme (ACE inhibitor, thiazid diuretic (indapamide and dihydropyridine calcium antagonist (nifedipine XL.Results. 200 patients with refractory HT were revealed. True refractory HT took place in 59,9% of patients and pseudo refractory HT – in 40,1% of patients. Lack of diuretics or combined antihypertensive therapy were the main reason of insufficient BP control. Proposed 3-drugs therapy resulted in reduction of systolic BP from 190 to 132 Hg mm and diastolic BP from 104 to 81 Hg mm. Target level of BP was reached in 94% patients. There were no side effects which demanded to stop therapy.Conclusion. High incidence of pseudorefractory HT (40,1% is revealed. Significant prevalence of renal disturbances especially chronic interstitial inflammatory could be responsible for refractory HT development. Use of 3-drugs therapy (ACE inhibitor, indapamide and nifedipine XL provides effective control of BP in refractory and pseudorefractory HT.

  9. RESULTS OF OUTPATIENT PROGRAM ON EFFECTIVE THERAPY OF REFRACTORY ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    M. M. Batyushin

    2007-01-01

    Full Text Available Aim. To increase in efficacy of antihypertensive therapy in patients with refractory arterial hypertension (HT.Material and methods. Patients with refractory HT were revealed during first month of program. The causes of refractory HT were analyzed. Combined antihypertensive therapy was prescribed to reach target level of blood pressure (BP. This therapy lasted 24 weeks and included angiotensin converting enzyme (ACE inhibitor, thiazid diuretic (indapamide and dihydropyridine calcium antagonist (nifedipine XL.Results. 200 patients with refractory HT were revealed. True refractory HT took place in 59,9% of patients and pseudo refractory HT – in 40,1% of patients. Lack of diuretics or combined antihypertensive therapy were the main reason of insufficient BP control. Proposed 3-drugs therapy resulted in reduction of systolic BP from 190 to 132 Hg mm and diastolic BP from 104 to 81 Hg mm. Target level of BP was reached in 94% patients. There were no side effects which demanded to stop therapy.Conclusion. High incidence of pseudorefractory HT (40,1% is revealed. Significant prevalence of renal disturbances especially chronic interstitial inflammatory could be responsible for refractory HT development. Use of 3-drugs therapy (ACE inhibitor, indapamide and nifedipine XL provides effective control of BP in refractory and pseudorefractory HT.

  10. LINX®, a novel treatment for patients with refractory asthma complicated by gastroesophageal reflux disease: a case report.

    Science.gov (United States)

    Sriratanaviriyakul, Narin; Kivler, Celeste; Vidovszky, Tamas J; Yoneda, Ken Y; Kenyon, Nicholas J; Murin, Susan; Louie, Samuel

    2016-05-24

    Gastroesophageal reflux disease is one of the most common comorbidities in patients with asthma. Gastroesophageal reflux disease can be linked to difficult-to-control asthma. Current management includes gastric acid suppression therapy and surgical antireflux procedures. The LINX® procedure is a novel surgical treatment for patients with gastroesophageal reflux disease refractory to medical therapy. To the best of our knowledge, we report the first case of successful treatment of refractory asthma secondary to gastroesophageal reflux disease using the LINX® procedure. Our patient was a 22-year-old white woman who met the American Thoracic Society criteria for refractory asthma that had remained poorly controlled for 5 years despite progressive escalation to step 6 treatment as recommended by National Institutes of Health-National Asthma Education and Prevention Program guidelines, including high-dose oral corticosteroids, high-dose inhaled corticosteroid plus long-acting β2-agonist, leukotriene receptor antagonist, and monthly omalizumab. Separate trials with azithromycin therapy and roflumilast did not improve her asthma control, nor did bronchial thermoplasty help. Additional consultations with two other university health systems left the patient with few treatment options for asthma, which included cyclophosphamide. Instead, the patient underwent a LINX® procedure after failure of maximal medical therapy for gastroesophageal reflux disease with the additional aim of improving asthma control. After she underwent LINX® treatment, her asthma improved dramatically and was no longer refractory. She had normal exhaled nitric oxide levels and loss of peripheral eosinophilia after LINX® treatment. Prednisone was discontinued without loss of asthma control. The only immediate adverse effects due to the LINX® procedure were bloating, nausea, and vomiting. LINX® is a viable alternative to the Nissen fundoplication procedure for the treatment of patients with

  11. Bone marrow immunophenotyping by flow cytometry in refractory cytopenia of childhood

    NARCIS (Netherlands)

    A.M. Aalbers (Anna Maartje); M.M. van den Heuvel-Eibrink (Marry); I. Baumann (Irith); M.N. Dworzak (Michael); H. Hasle (Henrik); F. Locatelli (Franco); B. de Moerloose (Barbara); M. Schmugge; E. Mejstříková (Ester); M. Nováková (Michaela); M. Zecca (Marco); C.M. Zwaan (Christian Michel); J.G. te Marvelde (Jeroen); A.W. Langerak (Anton); J.J.M. van Dongen (Jacques); R. Pieters (Rob); C.M. Niemeyer (Charlotte); V.H.J. van der Velden (Vincent)

    2015-01-01

    textabstractRefractory cytopenia of childhood is the most common type of childhood myelodysplastic syndrome. Because the majority of children with refractory cytopenia have a normal karyotype and a hypocellular bone marrow, differentiating refractory cytopenia from the immune-mediated bone marrow

  12. Selection and application of C18200 chrome copper for the OHTE confinement test helical coil

    International Nuclear Information System (INIS)

    Puhn, F.A.; Graumann, D.W.

    1981-01-01

    The selection and qualification of copper for the OHTE confinement test helical coil (H-coil) was a crucial step in the success of this new experiment. Previous problems encountered at General Atomic Company with close tolerance machined parts made from high strength copper were identified. The design criteria included selecting a material with minimal warpage during machining, an electrical conductivity >80% IACS, and a yield strength of at least 241 Mpa (35 ksi). The investigation of candidate materials and testing samples led to selection of a material that fully met all requirements. The C18200 chrome copper forged plates were supplied by the Ampco Metal Division of Ampco-Pittsburgh Corporation

  13. A comparative view of radiation, photo and photocatalytically induced oxidation of water pollutants

    International Nuclear Information System (INIS)

    Getoff, N.

    1997-01-01

    Water resources are presently overloaded with biologically resistant (refractory) pollutants. Several oxidation methods have been developed for their degradation, the most efficient of which is irradiation treatment, particularly that based on e-beam processing in the presence of O 2 /O 3 . The next-best method is photoinduced pollutant oxidation with VUV- and/or UV-light, using H 2 O 2 or H 2 O 2 /O 3 as an additional source of OH radicals. The photocatalytic method, using e.g. TiO 2 as a catalyst in combination with oxidation agents such as H 2 O 2 or H 2 O 2 /O 3 , is also recommended. The suitability of these three methods is illustrated by examples and they are briefly discussed and compared on the basis of the energy consumption and efficiency. Other methods, such as ozone treatment, the photo-Fenton process, ultrasonic and electrochemical treatments, as well as the well known biological process and thermal oxidation of refractory pollutants, are briefly mentioned. (author)

  14. Corrosão de refratários utilizados na siderurgia. Parte II: propriedades físicas dos refratários e fatores operacionais Corrosion of refractories used in steel metallurgy. Part II: refractories physical properties and operating factor

    Directory of Open Access Journals (Sweden)

    S. R. Bragança

    2012-12-01

    Full Text Available Foi realizada uma revisão dos principais aspectos encontrados na literatura especializada sobre corrosão de refratários, avaliando-se a viabilidade de determinados ensaios e relacionando-os com os resultados experimentais. Na primeira parte deste trabalho foram abordadas as principais propriedades da microestrutura dos refratários, como a qualidade dos agregados e da matriz, incluindo-se a fase ligante (como resinas ou piche, presença de carbono, porosidade e aditivos antioxidantes. Nesta segunda parte os demais aspectos ligados à corrosão, como as propriedades físico-químicas dos refratários, as características das escórias e das condições operacionais são discutidas, sempre, relacionando-se a teoria com dados da prática industrial. Especificamente, analisaram-se os refratários de linha de escória de panela de aço.In this study, the main aspects found in the literature about refractories corrosion were reviewed, evaluating the feasibility of certain tests and relating them with experimental results. In the first part of this work, the main properties of the microstructure of the refractories were discussed, such as aggregates and the matrix, including the binder phase (resins or pitch, presence of carbon, porosity, additives and anti-oxidants. In this second part, the remaining aspects of corrosion, such as physical and chemical properties of refractories, slag characteristics and operating conditions are discussed, linking the theory with data from industrial practice. Specifically, it was analyzed the refractory from slag-line of steel ladle.

  15. Nucleotide sequence and genetic organization of Hungarian grapevine chrome mosaic nepovirus RNA2.

    Science.gov (United States)

    Brault, V; Hibrand, L; Candresse, T; Le Gall, O; Dunez, J

    1989-10-11

    The complete nucleotide sequence of hungarian grapevine chrome mosaic nepovirus (GCMV) RNA2 has been determined. The RNA sequence is 4441 nucleotides in length, excluding the poly(A) tail. A polyprotein of 1324 amino acids with a calculated molecular weight of 146 kDa is encoded in a single long open reading frame extending from nucleotides 218 to 4190. This polyprotein is homologous with the protein encoded by the S strain of tomato black ring virus (TBRV) RNA2, the only other nepovirus sequenced so far. Direct sequencing of the viral coat protein and in vitro translation of transcripts derived from cDNA sequences demonstrate that, as for comoviruses, the coat protein is located at the carboxy terminus of the polyprotein. A model for the expression of GCMV RNA2 is presented.

  16. Colectomy for refractory constipation

    DEFF Research Database (Denmark)

    Raahave, Dennis; Loud, Franck Bjørn; Christensen, Elsebeth

    2010-01-01

    OBJECTIVE: This study evaluated the type of colectomy, postoperative complications, functional results, and satisfaction in patients with constipation refractory to conservative therapy. Further, colonic transit time (CTT), faecal load (coprostasis), and colon length (redundancies) were compared ...

  17. The compatibility of chromium-aluminium steels with high pressure carbon dioxid at intermediate- temperatures; Compatibilite des aciers au chrome-aluminium avec le gaz carbonique sous pression aux temperatures moyennes

    Energy Technology Data Exchange (ETDEWEB)

    Leclercq, D; Loriers, H; David, R; Darras, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    With a view to their use in the exchangers of nuclear reactors of the graphite-gas or heavy water-gas types, the behaviour of chromium-aluminium steels containing up to 7 per cent chromium and 1.5 per cent aluminium has been studied in the presence of high-pressure carbon dioxide at temperatures of between 400 and 700 deg. C. The two most interesting grades of steel (2 per cent Cr - 0.35 per cent Al - 0.35 per cent Mo and 7 per cent Cr - 1.5 per cent Al - 0.6 per cent Si) are still compatible with carbon dioxide up to 550 and 600 deg. C respectively. A hot dip aluminised coating considerably increases resistance to oxidation of the first grade and should make possible its use up to temperatures of at least 600 deg. C. (authors) [French] Dans l'optique de leur emploi dans les echangeurs de reacteurs nucleaires des filieres graphite-gaz ou eau lourde-gaz, le comportement en presence de gaz carbonique sous pression d'aciers au chrome-aluminium, contenant jusqu'a 7 pour cent de chrome et 1,5 pour cent d'aluminium a ete etudie entre 400 et 700 deg. C. Les deux nuances les plus interessantes (2 pour cent Cr - 0,35 pour cent Al - 0,35 pour cent Mo et 7 pour cent Cr - 1,5 pour cent Al - 0,6 pour cent Si) restent compatibles avec le gaz carbonique jusqu'a 550 et 600 deg. C respectivement. Un revetement d'aluminium, effectue par immersion dans un bain fondu, ameliore notablement la resistance a l'oxydation de la premiere et doit permettre son empioi jusqu'a 600 deg. C au moins. (auteurs)

  18. Statistical experimental design for refractory coatings

    International Nuclear Information System (INIS)

    McKinnon, J.A.; Standard, O.C.

    2000-01-01

    The production of refractory coatings on metal casting moulds is critically dependent on the development of suitable rheological characteristics, such as viscosity and thixotropy, in the initial coating slurry. In this paper, the basic concepts of mixture design and analysis are applied to the formulation of a refractory coating, with illustration by a worked example. Experimental data of coating viscosity versus composition are fitted to a statistical model to obtain a reliable method of predicting the optimal formulation of the coating. Copyright (2000) The Australian Ceramic Society

  19. Beta-blockers in cirrhosis and refractory ascites

    DEFF Research Database (Denmark)

    Kimer, Nina; Feineis, Martin; Møller, Søren

    2015-01-01

    OBJECTIVE: It is currently discussed if beta-blockers exert harmful effects and increase mortality in patients with cirrhosis and refractory ascites. In this study, we provide an overview of the available literature in this field in combination with a retrospective analysis of 61 patients...... trials (9 trials on propranolol, 1 case-control study and 4 retrospective analyses) were identified. One trial suggested an increased mortality in patients treated with beta-blockers and refractory ascites. The results of the remaining trials were inconclusive. No increase in mortality among beta-blocker......-treated patients was found in the present retrospective analysis. CONCLUSIONS: Treatment with beta-blockers may increase mortality in patients with cirrhosis and refractory ascites. However, the current evidence is sparse and high-quality studies are warranted to clarify the matter....

  20. The degradation of lining of rotary furnaces in the production of zinc oxide

    Czech Academy of Sciences Publication Activity Database

    Luptáková, Natália; Pešlová, F.; Anisimov, E.

    2014-01-01

    Roč. 21, č. 3 (2014), s. 116-121 ISSN 1335-0803 Institutional support: RVO:68081723 Keywords : zinc oxide * the production of zinc oxide * zinc slag * refractories * the degradation of rotary furnace linings Subject RIV: JG - Metallurgy http://ojs.mateng.sk/index.php/Mateng/article/view/133/194

  1. Fire and explosion hazards of refractory compound powders

    International Nuclear Information System (INIS)

    Krivtsov, V.A.; Kostina, E.S.

    1978-01-01

    Data on fire and explosion hazards of refractory compound powders (HfC, ZrC,LaB 6 , ZrN, etc.) are presented. It is shown that refractory compounds can be fire- and exposion hazardous in various degrees. Qualitative and quantitative estimations of one of fire-hazard characteristics - smoldering temperature - are presented

  2. Steam explosion studies with single drops of molten refractory materials

    International Nuclear Information System (INIS)

    Nelson, L.S.

    1980-01-01

    Laser heating, levitation melting, and metal combustion were used to prepare individual drops of molten refractory materials which simulate LWR fuel melt products. Drop temperatures ranged from approx. = 1500 to > 3000K. These drops, several millimeters in diameter, were injected into water and subjected to pressure transients (approx. = 1MPa peak pressures) generated by a submerged exploding bridgewire. Molten oxides of Fe, Al and Zr could be induced to explode with bridgewire initiation. High speed films showed the explosions with exceptional clarity, and pressure transducer records could be correlated with individual frames in the films. Pressure spikes one or two MPa high were generated whenever an explosion occurred. Debris particles were mostly spheroidal, with diameters in the range 10 to 1000 μm

  3. Extra-corporeal membrane oxygenation in the management of 2009 influenza A (H1N1) refractory respiratory failure.

    LENUS (Irish Health Repository)

    Das, J P

    2012-02-01

    Rapidly progressive acute respiratory failure attributed to 2009 H1N1 influenza A infection has been reported worldwide-3. Refractory hypoxaemia despite conventional mechanical ventilation and lung protective strategies has resulted in the use a combination of rescue therapies, such as conservative fluid management, prone positioning, inhaled nitric oxide, high frequency oscillatory ventilation and extracorporeal membrane oxygenation (ECMO)4. ECMO allows for pulmonary or cardiopulmonary support as an adjunct to respiratory and cardiac failure, minimising ventilator-associated lung injury (VALI). This permits treatment of the underlying disease process, while concurrently allowing for recovery of the acute lung injury. This case documents a previously healthy twenty-two year old Asian male patient with confirmed pandemic (H 1N1) 2009 influenza A who was successfully managed with ECMO in the setting of severe refractory hypoxaemia and progressive hypercapnia.

  4. Extra-corporeal membrane oxygenation in the management of 2009 influenza A (H1N1) refractory respiratory failure.

    LENUS (Irish Health Repository)

    Das, J P

    2011-03-01

    Rapidly progressive acute respiratory failure attributed to 2009 H1N1 influenza A infection has been reported worldwide-3. Refractory hypoxaemia despite conventional mechanical ventilation and lung protective strategies has resulted in the use a combination of rescue therapies, such as conservative fluid management, prone positioning, inhaled nitric oxide, high frequency oscillatory ventilation and extracorporeal membrane oxygenation (ECMO)4. ECMO allows for pulmonary or cardiopulmonary support as an adjunct to respiratory and cardiac failure, minimising ventilator-associated lung injury (VALI). This permits treatment of the underlying disease process, while concurrently allowing for recovery of the acute lung injury. This case documents a previously healthy twenty-two year old Asian male patient with confirmed pandemic (H 1N1) 2009 influenza A who was successfully managed with ECMO in the setting of severe refractory hypoxaemia and progressive hypercapnia.

  5. Improved oxidation resistance of group VB refractory metals by Al+ ion implantation

    International Nuclear Information System (INIS)

    Hampikian, J.M.

    1996-01-01

    Aluminum ion implantation of vanadium, niobium, and tantalum improved the metals' oxidation resistances at 500 C and 735 C. Implanted vanadium oxidized only to one-third the extent of unimplanted vanadium when exposed at 500 C to air. The oxidative weight gains of implanted niobium and tantalum proved negligible when measured at 500 C and for times sufficient to fully convert the untreated metals to their pentoxides. At 735 C, implantation of vanadium only slightly retarded its oxidation, while oxidative weight gains of niobium and tantalum were reduced by factors of 3 or more. Implanted niobium exhibited weight gain in direct proportion to oxidation time squared at 735 C. Microstructural examination of the metals implanted with selected fluences of the 180 kV aluminum ions showed the following. The solubility limit of aluminum is extended by implantation, the body centered cubic (bcc) phases being retained to ∼60 at. pct Al in all three metals. The highest fluence investigated, 2.4 x 10 22 ions/m 2 , produced an ∼400-nm layer of VAl 3 beneath the surface of vanadium, and ∼300-nm layers of an amorphous phase containing ∼70 at. pct Al beneath the niobium and tantalum surfaces. All three metals, implanted to this fluence and annealed at 600 C, contained tri-aluminides, intermetallic compounds known for their oxidation resistances. Specimens implanted to this fluence were thus selected for the oxidation measurements

  6. Roasting of refractory gold and silver concentrate; Tostacion de un concentrado refractario de oro y plata

    Energy Technology Data Exchange (ETDEWEB)

    Coraonado, J. H.; Encinas, M. A.; Leyva, M. A.; Valenzuela, J. L.; Valenzuela, A.; Munive, G. T.

    2012-11-01

    In processing of precious metal ores with high pyrite content, refractory concentrates are obtained, which are difficult to process. A refractory gold and silver concentrate was leached with sodium cyanide. Results show low extraction percentages, being 34 % of gold and 40 % of silver. A roasting method to oxidize the concentrate was used, making it more susceptible to cyanidation, hence a more efficient way to extract precious metals. The variables include roasting temperature and roasting and cyanidation time. In addition, the hot calcine was added to the leaching solution at room temperature to analyze the effect on particle size and recovery. The best results, although not entirely satisfactory (50 % of gold and 61 % of silver) were obtained by roasting the concentrate for 4 h at 600 degree centigrade, followed by cyanidation for 20 h. The lime consumption to raise the pH to about 11.3 was increased markedly to 25 kg/m{sup 3}. (Author) 11 refs.

  7. Joint Test Protocol: Environmentally Friendly Zirconium Oxide Pretreatment Demonstration

    Science.gov (United States)

    2013-12-01

    and compliance issues associated with the use of zinc phosphate and chromate/ chrome containing conversion coatings while maintaining military...safety, and occupational health risks associated with the use of zinc phosphate and chromate/ chrome -containing conversion coatings. There is a need to...zirconium-based pretreatment will be shown to be both environmentally acceptable (no hazardous air pollutants or heavy metals such as hexavalent chromium

  8. Immunomodulatory therapy in refractory/recurrent ovarian cancer.

    Science.gov (United States)

    Chen, Chao-Yu; Lai, Chyong-Huey; Yang, Lan-Yan; Tang, Yun-Hsin; Chou, Hung-Hsueh; Chang, Chee-Jen; Lin, Cheng-Tao

    2015-04-01

    To investigate the efficacy and toxicity of immunomodulatory therapy (IMT) alone or as an add-on to palliative/salvage chemotherapy in patients with refractory/recurrent epithelial ovarian cancer (EOC). We retrospectively analyzed the efficacy and toxicity of IMT in 15 patients with refractory/recurrent EOC who had previously received multiple chemotherapy regimens. The median age of the patients was 56 years (range, 41-75 years). Three patients were platinum-sensitive, two were platinum-resistant, and the remaining 10 patients were refractory to platinum-based front-line chemotherapy. IMT consisted of picibanil (OK-432) on Day 1, interleukin-2 and/or interferon-α on Day 2 administered by subcutaneous injection (every week or 2-weekly). Five patients never received metronomic oral cyclophosphamide. After IMT, three patients achieved partial remission (PR, lasting for 11 months, ≥ 12 months, and 16 months), and six patients had stable disease (SD). The disease stabilizing rate (PR+SD) was 60% (3/3 in platinum-sensitive and 6/12 in platinum-resistant/refractory patients). The absolute lymphocyte count (ALC) at 1 month after IMT was significantly higher in the PR+SD group (median 1242.0/μL) than in the progression group (median 325.0/μL) (p = 0.012). No ≥ Grade 3 toxicities were observed. The median post-IMT survival time was 12 months (range, 2-39 months). IMT alone or add-on to palliative/salvage chemotherapy for refractory/recurrent EOC achieves a substantial disease stabilizing rate without severe toxicity, which might be a potential option in selected patients. The ALC 1 month after IMT could be an early indicator to disease stabilization. Copyright © 2015. Published by Elsevier B.V.

  9. Chromate dermatitis from a boiler lining.

    Science.gov (United States)

    Rycroft, R J; Calnan, C D

    1977-08-01

    Chromate dermatitis is described in a mechanical fitter working inside boiler combustion chambers. A source of hexavalent chromate is traced to the action of the heat and alkaline fuel ash on trivalent chrome ore in parts of the refractory lining. Removal of the patient from this contact has resulted in almost complete clearing of his dermatitis, without any relapse, during a 9-month follow-up period.

  10. Cost Estimate for Gun Liner Emplacement

    Science.gov (United States)

    2011-08-01

    excellent material to resist wear and erosion in gun tubes, it is applied by an electrolytic process that involves hexavalent chromium, a known carcinogen...A recent Department of Defense memorandum has strongly urged that, wherever possible, processes involving hexavalent chromium be eliminated from...might be affordable.) Other refractory metals, such as the Stellite series, BioDur CCM* (a cobalt, chrome , molybdenum alloy), or niobium are less

  11. Estimation of environmental mobility of heavy metals using a sequential leaching of particulate material emitted from an opencast chrome mine complex

    Energy Technology Data Exchange (ETDEWEB)

    Poeykioe, R. [Meri-Lappi Institute, Centre for Environmental Technology, University of Oulu, Kemi (Finland); Peraemaeki, P.; Kuokkanen, T. [University of Oulu, Department of Chemistry, Oulu (Finland); Vaelimaeki, I. [Suomen Ympaeristoepalvelu Oy, Oulu (Finland)

    2002-06-01

    A four-stage sequential leaching procedure was applied to assess the bioavailability and environmental mobility of heavy metals (Cr, Fe, Cu, Ni and Cd) in total suspended particulate (TSP) material emitted from an opencast chrome mine complex (Kemi, Northern Finland). TSP material was collected on glass fibre filters by a high-volume sampler, and a sequential leaching procedure was used to determine the distribution of heavy metals between the water-soluble fraction (H{sub 2}O), environmentally mobile fraction (CH{sub 3}COONH{sub 4}), the fraction bound to carbonate and oxides (HONH{sub 3}Cl + CH{sub 3}COOH), and the fraction bound to silicates and organic matter, that is the environmentally immobile fraction (HNO{sub 3} + HF + HCl). The sequential leaching procedure was also applied to the certified reference materials VKI (QC Loam Soil A) and PACS-2 (Marine Sediment) to evaluate the accuracy and reproducibility of the leaching procedure. The heavy metals were determined by graphite furnace atomic absorption spectrometry (GFAAS) and flame atomic absorption spectrometry (FAAS). The concentrations of metals in the water-soluble fraction (H{sub 2}O) decreased in the order Fe >Cu >Cr >Ni >Cd, and in the environmentally mobile fraction (CH{sub 3}COONH{sub 4}) in the order Cu >Fe >Ni >Cr >Cd. (orig.)

  12. [Therapy-resistant and therapy-refractory arterial hypertension].

    Science.gov (United States)

    Wallbach, M; Koziolek, M J

    2018-05-02

    Therapy-resistant and therapy-refractory arterial hypertension differ in prevalence, pathogenesis, prognosis and therapy. In both cases, a structured approach is required, with the exclusion of pseudoresistance and, subsequently, secondary hypertension. Resistant hypertension has been reported to be more responsive to intensified diuretic therapy, whereas refractory hypertension is presumed to require sympathoinhibitory therapy. Once the general measures and the drug-based step-up therapy have been exhausted, interventional procedures are available.

  13. Refractory myasthenia gravis – clinical profile, comorbidities and response to rituximab

    Science.gov (United States)

    Sudulagunta, Sreenivasa Rao; Sepehrar, Mona; Sodalagunta, Mahesh Babu; Settikere Nataraju, Aravinda; Bangalore Raja, Shiva Kumar; Sathyanarayana, Deepak; Gummadi, Siddharth; Burra, Hemanth Kumar

    2016-01-01

    Introduction: Myasthenia gravis (MG) is an antibody mediated autoimmune neuromuscular disorder characterized by fatigable muscle weakness. A proportion of myasthenia gravis patients are classified as refractory due to non responsiveness to conventional treatment. This retrospective study was done to evaluate clinical profile, epidemiological, laboratory, and features of patients with MG and mode of management using rituximab and complications. Methods: Data of myasthenia gravis patients admitted or presented to outpatient department (previous medical records) with MG between January 2008 and January 2016 were included. A total of 512 patients fulfilled the clinical and diagnostic criteria of myasthenia gravis of which 76 patients met the diagnostic certainty for refractory myasthenia gravis and were evaluated. Results: Out of 76 refractory MG patients, 53 (69.73%) patients fulfilled all the three defined criteria. The median age of onset of the refractory MG group was 36 years with a range of 27–53 years. In our study 25 patients (32.89%) belonged to the age group of 21–30 years. Anti-MuSK antibodies were positive in 8 non-refractory MG patients (2.06%) and 36 refractory MG patients (47.36%). Mean HbA1C was found to be 8.6±2.33. The dose of administered prednisone decreased by a mean of 59.7% (p=3.3x10–8) to 94.6% (p=2.2x10–14) after the third cycle of rituximab treatment. Conclusion: The refractory MG patients are most commonly female with an early age of onset, anti-MuSK antibodies, and thymomas. Refractory MG patients have higher prevalence and poor control (HbA1C >8%) of diabetes mellitus and dyslipidemia probably due to increased steroid usage. Rituximab is very efficient in treatment of refractory MG with adverse effects being low. PMID:27790079

  14. IMPROVED CORROSION RESISTANCE OF ALUMINA REFRACTORIES

    Energy Technology Data Exchange (ETDEWEB)

    John P. Hurley; Patty L. Kleven

    2001-09-30

    The initial objective of this project was to do a literature search to define the problems of refractory selection in the metals and glass industries. The problems fall into three categories: Economic--What do the major problems cost the industries financially? Operational--How do the major problems affect production efficiency and impact the environment? and Scientific--What are the chemical and physical mechanisms that cause the problems to occur? This report presents a summary of these problems. It was used to determine the areas in which the EERC can provide the most assistance through bench-scale and laboratory testing. The final objective of this project was to design and build a bench-scale high-temperature controlled atmosphere dynamic corrosion application furnace (CADCAF). The furnace will be used to evaluate refractory test samples in the presence of flowing corrodents for extended periods, to temperatures of 1600 C under controlled atmospheres. Corrodents will include molten slag, steel, and glass. This test should prove useful for the glass and steel industries when faced with the decision of choosing the best refractory for flowing corrodent conditions.

  15. A novel RE-chrome-boronizing technology assisted by fast multiple rotation rolling treatment at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Xing-dong [School of Materials Science and Engineering, Shandong University, Jinan 250061 (China); School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101 (China); Xu, Bin, E-mail: xubin@sdjzu.edu.cn [School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101 (China); Cai, Yu-cheng [School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101 (China)

    2015-12-01

    Highlights: • A nanostructured layer with grain size of approximately 30 nm was successfully fabricated in the upper-layer of carbon steel. • The penetrating rate was enhanced significantly by the fast multiple rotation rolling (FMRR) treatment at low temperature. • A novel and efficient RE-Chrome-Boronizing technology assisted by fast multiple rotation rolling (FMRR) treatment at low temperature was used to fabricate boride layers on the surface of carbon steel. - Abstract: The boride layer was fabricated on the surface of carbon steel by a novel RE-Chrome-Boronizing technology assisted by fast multiple rotation rolling (FMRR) treatment at low temperature. The microstructure of the boride layer was characterized by using scanning electron microscopy (SEM). The microstructure of the top surface layer of substrate was characterized by transmission electron microscopy (TEM) and high resolution rransmission electron microscopy (HRTEM). Experimental results showed that a nanostructured layer with grain size of approximately 30 nm was obtained; the amorphous phase and high-density dislocations were observed in upper-layer of FMRR samples, which led to the reduction of diffusion activation energy of boron atoms. Boride layers fabricated on the FMRR samples are continuous, dense, uniform, and low in brittleness. The penetrating rate was enhanced significantly when the FMRR samples were Cr-Rare earth-boronized at 650 °C for 6 h. The thickness of the boride layer of FMRR samples on carbon steel was approximately 25 μm when the duration was 60 min, which was approximately 1.5 times higher than the original sample. The boride layer consisted of mainly Fe2B, and adheres well to the metallic substrate.

  16. Clinical and microbiological features of refractory periodontitis subjects.

    Science.gov (United States)

    Colombo, A P; Haffajee, A D; Dewhirst, F E; Paster, B J; Smith, C M; Cugini, M A; Socransky, S S

    1998-02-01

    The purpose of this investigation was to compare the clinical parameters and the site prevalence and levels of 40 subgingival species in successfully treated and refractory periodontitis subjects. 94 subjects received scaling and root planing and if needed, periodontal surgery and systemically administered tetracycline. 28 refractory subjects showed mean full mouth attachment loss and/or > 3 sites showing attachment loss > 2.5 mm within 1 year post-therapy. 66 successfully treated subjects showed mean attachment level gain and no sites with attachment loss > 2.5 mm. Baseline subgingival plaque samples were taken from the mesial aspect of each tooth and the presence and levels of 40 subgingival taxa were determined using whole genomic DNA probes and checkerboard DNA-DNA hybridization. The mean levels and % of sites colonized by each species (prevalence) was computed for each subject and differences between groups sought using the Mann-Whitney test. Most of the 40 species tested, including Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Bacteroides forsythus, were equally or less prevalent in the refractory group. Prevotella nigrescens was significantly more prevalent in successfully treated subjects, while refractory subjects harbored a larger proportion of Streptococcus species, particularly Streptococcus constellatus. The odds of a subject being refractory was 8.6 (p or = 3.5% of the total DNA probe count. Since few microbiological differences existed between treatment outcome groups using DNA probes to known species, the predominant cultivable microbiota of 33 subgingival samples from 14 refractory subjects was examined. 85% of the 1649 isolates were identified using probes to 69 recognized subgingival species. The remaining unidentified strains were classified by analyzing 16S rRNA gene sequences. Many sequenced isolates were of taxa not considered a common part of the oral microbiota such as Acinetobacter baumanni

  17. Oxidation of pyrite: Consequences and significance

    Directory of Open Access Journals (Sweden)

    Dimitrijević Mile D.

    2002-01-01

    Full Text Available This paper presents the most important studies on the oxidation of pyrite particularly in aqueous solutions. The consequences of pyrite oxidation was examined, as well as its importance, from both the technical-technological and environmental points of view. The oxidation of pyrite was considered in two parts. The spontaneous oxidation of pyrite in nature was described in the first part, with this part comprising pyrite oxidation in deposits depots and mines. It is explained how way natural electrochemical processes lead to the decomposition of pyrite and other minerals associated with pyrite. The oxidation of pyrite occurring during technological processes such as grinding, flotation and leaching, was shown in the second part. Particular emphasis was placed on the oxidation of pyrite during leaching. This part includes the leaching of sulphide and oxide ores, the leaching of pyrite coal and the leaching of refractory gold-bearing ores (pressure oxidation, bacterial oxidation, oxidation by means of strong oxidants and the electrolysis of pyrite suspensions. Various mechanisms of pyrite oxidation and of the galvanic interaction of pyrite with other sulphide minerals are shown.

  18. Timing of Secondary Hydrothermal Alteration of the Luobusa Chromitites Constrained by Ar/Ar Dating of Chrome Chlorites

    Directory of Open Access Journals (Sweden)

    Wei Guo

    2018-05-01

    Full Text Available Chrome chlorites are usually found as secondary phases formed by hydrothermal alteration of chromite deposits and associated mafic/ultramafic rocks. Here, we report the 40Ar/39Ar age of chrome chlorites separated from the Luobusa massive chromitites which have undergone secondary alteration by CO2-rich hydrothermal fluids. The dating results reveal that the intermediate heating steps (from 4 to 10 of sample L7 generate an age plateau of 29.88 ± 0.42 Ma (MSWD = 0.12, plateau 39Ar = 74.6%, and the plateau data points define a concordant inverse isochron age of 30.15 ± 1.05 Ma (MSWD = 0.08, initial 40Ar/36Ar = 295.8 ± 9.7. The Ar release pattern shows no evidence of later degassing or inherited radiogenic component indicated by an atmospheric intercept, thus representing the age of the hydrothermal activity. Based on the agreement of this hydrothermal age with the ~30 Ma adakitic plutons exposed in nearby regions (the Zedong area, tens of kilometers west Luobusa and the extensive late Oligocene plutonism distributed along the southeastern Gangdese magmatic belt, it is suggested that the hydrothermal fluids are likely related to the ~30 Ma magmatism. The hydrothermal fluid circulation could be launched either by remote plutons (such as the Sangri granodiorite, the nearest ~30 Ma pluton west Luobusa or by a similar coeval pluton in the local Luobusa area (inferred, not found or reported so far. Our results provide important clues for when the listwanites in Luobusa were formed.

  19. Defining refractory migraine: results of the RHSIS Survey of American Headache Society members.

    Science.gov (United States)

    Schulman, Elliott A; Peterlin, B Lee; Lake, Alvin E; Lipton, Richard B; Hanlon, Alexandra; Siegel, Sherry; Levin, Morris; Goadsby, Peter J; Markley, Herbert G

    2009-04-01

    To gauge consensus regarding a proposed definition for refractory migraine proposed by Refractory Headache Special Interest Section, and where its use would be most appropriate. Headache experts have long recognized that a subgroup of headache sufferers remains refractory to treatment. Although different groups have proposed criteria to define refractory migraine, the definition remains controversial. The Refractory Headache Special Interest Section of the American Headache Society developed a definition through a consensus process, assisted by a literature review and initial membership survey. A 12-item questionnaire was distributed at the American Headache Society meeting in 2007 during a platform session and at the Refractory Headache Special Interest Section symposium. The same questionnaire was subsequently sent to all American Headache Society members via e-mail. A total of 151 responses from AHS members form the basis of this report. The survey instrument was designed using Survey Monkey. Frequencies and percentages of the survey were used to describe survey responses. American Headache Society members agreed that a definition for refractory migraine is needed (91%) that it should be added to the International Classification of Headache Disorders-2 (86%), and that refractory forms of non-migraine headache disorders should be defined (87%). Responders believed a refractory migraine definition would be of greatest value in selecting patients for clinical drug trials. The current refractory migraine definition requires a diagnosis of migraine, interference with function or quality of life despite modification of lifestyle factors, and adequate trials of acute and preventive medicines with established efficacy. The proposed criteria for the refractory migraine definition require failing 2 preventive medications to meet the threshold for failure. Although 42% of respondents agreed with the working definition of refractory migraine, 43% favored increasing the

  20. Obtainment of tantalum oxide from national ores

    International Nuclear Information System (INIS)

    Pinatti, D.G.; Ribeiro, S.; Martins, A.H.

    1988-01-01

    The experimental results of tantalum oxides (Ta 2 O 5 ) obtainment from Brazilian ores of tantalite and columbite are described. This study is a part of the technologic and scientific research design of refractory metals (Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W) and correlate ceramics. (C.G.C.) [pt

  1. The Role of Refractory Dissolved Organic Matter in Ocean Carbon Sequestration

    DEFF Research Database (Denmark)

    Jørgensen, Linda

    The ocean assimilates a large amount of atmospheric CO2 and is potentially a buffer for climate change. A fraction of the assimilated CO2 is incorporated into algal biomass and further converted into refractory dissolved organic matter (DOM). Carbon bound in refractory DOM has the potential...... studies the prokaryotic production and degradation of oceanic refractory DOM and discusses the reasons for the persistent nature of this large DOM fraction. The first two papers investigate the microbial carbon pump, i.e. prokaryotic transfor-mation of organic carbon into refractory DOM. The results show...... DOM compounds in the ocean are rare—possibly too rare to sustain viable uptake and assimilation. Hence, the dilute concentration of individual compounds is a possible explanation for the apparent refractory nature of most DOM in the ocean. Understanding the mechanisms that control the quality...

  2. Intraepithelial lymphocytes in refractory celiac disease : lost in transition

    NARCIS (Netherlands)

    Schmitz, Frederike

    2014-01-01

    Refractory coeliac disease type II (RCDII) is a severe complication of coeliac disease. Whereas celiac disease can successfully be treated by the strict avoidance of gluten, refractory celiac patients show no remission despite a gluten-free diet. The pathology of RCDII is only partially understood,

  3. Clinical Features of Refractory Ascites in Outpatients

    Directory of Open Access Journals (Sweden)

    Wanda Regina Caly

    Full Text Available OBJECTIVES: To present the clinical features and outcomes of outpatients who suffer from refractory ascites. METHODS: This prospective observational study consecutively enrolled patients with cirrhotic ascites who submitted to a clinical evaluation, a sodium restriction diet, biochemical blood tests, 24 hour urine tests and an ascitic fluid analysis. All patients received a multidisciplinary evaluation and diuretic treatment. Patients who did not respond to the diuretic treatment were controlled by therapeutic serial paracentesis, and a transjugular intrahepatic portosystemic shunt was indicated for patients who required therapeutic serial paracentesis up to twice a month. RESULTS: The most common etiology of cirrhosis in both groups was alcoholism [49 refractory (R and 11 non-refractory ascites (NR]. The majority of patients in the refractory group had Child-Pugh class B cirrhosis (p=0.034. The nutritional assessment showed protein-energy malnutrition in 81.6% of the patients in the R group and 35.5% of the patients in the NR group, while hepatic encephalopathy, hernia, spontaneous bacterial peritonitis, upper digestive hemorrhage and type 2 hepatorenal syndrome were present in 51%, 44.9%, 38.8%, 38.8% and 26.5% of the patients in the R group and 9.1%, 18.2%, 0%, 0% and 0% of the patients in the NR group, respectively (p=0.016, p=0.173, p=0.012, p=0.012, and p=0.100, respectively. Mortality occurred in 28.6% of the patients in the R group and in 9.1% of the patients in the NR group (p=0.262. CONCLUSION: Patients with refractory ascites were malnourished, suffered from hernias, had a high prevalence of complications and had a high postoperative death frequency, which was mostly due to infectious processes.

  4. Resistant and Refractory Hypertension: Antihypertensive Treatment Resistance vs Treatment Failure

    Science.gov (United States)

    Siddiqui, Mohammed; Dudenbostel, Tanja; Calhoun, David A.

    2017-01-01

    Resistant or difficult to treat hypertension is defined as high blood pressure that remains uncontrolled with 3 or more different antihypertensive medications, including a diuretic. Recent definitions also include controlled blood pressure with use of 4 or more medications as also being resistant to treatment. Recently, refractory hypertension, an extreme phenotype of antihypertensive treatment failure has been defined as hypertension uncontrolled with use of 5 or more antihypertensive agents, including a long-acting thiazide diuretic and a mineralocorticoid receptor antagonist. Patients with resistant vs refractory hypertension share similar characteristics and comorbidities, including obesity, African American race, female sex, diabetes, coronary heart disease, chronic kidney disease, and obstructive sleep apnea. Patients with refractory vs resistant hypertension tend to be younger and are more likely to have been diagnosed with congestive heart failure. Refractory hypertension might also differ from resistant hypertension in terms of underlying cause. Preliminary evidence suggests that refractory hypertension is more likely to be neurogenic in etiology (ie, heightened sympathetic tone), vs a volume-dependent hypertension that is more characteristic of resistant hypertension in general. PMID:26514749

  5. Performance assessment of refractory samples in the Los Alamos Controlled Air Incinerator

    International Nuclear Information System (INIS)

    Hutchins, D.A.; Borduin, L.C.; Koenig, R.A.; Vavruska, J.S.; Warner, C.L.

    1986-01-01

    A refractory evaluation project was initiated in 1979 to study the performance of six selected refractory materials within the Los Alamos Controlled Air Incinerator (CAI). Determining refractory resistance to thermal shock, chemical attack, and plutonium uptake was of particular interest. The experimental refractories were subjected to a variety of waste materials, including transuranic (TRU) contaminated wastes, highly chlorinated compounds and alkaline metal salts of perchlorate, chlorate, nitrate and oxylate, over the six year period of this study. Results of this study to date indicate that the use of high alumina, and possibly specialty plastic refractories, is advisable for the lining of incinerators used for the thermal destruction of diverse chemical compounds. 12 refs., 4 tabs

  6. White-Coat Effect Is Uncommon in Patients With Refractory Hypertension.

    Science.gov (United States)

    Siddiqui, Mohammed; Judd, Eric K; Oparil, Suzanne; Calhoun, David A

    2017-09-01

    Refractory hypertension is a recently described phenotype of antihypertensive treatment failure defined as uncontrolled blood pressure (BP) despite the use of ≥5 different antihypertensive agents, including chlorthalidone and spironolactone. Recent studies indicate that refractory hypertension is uncommon, with a prevalence of ≈5% to 10% of patients referred to a hypertension specialty clinic for uncontrolled hypertension. The prevalence of white-coat effect, that is, uncontrolled automated office BP ≥135/85 mm Hg and controlled out-of-office BP hypertensive patients overall is ≈30% to 40%. The prevalence of white-coat effect among patients with refractory hypertension has not been previously reported. In this prospective evaluation, consecutive patients referred to the University of Alabama at Birmingham Hypertension Clinic for uncontrolled hypertension were enrolled. Refractory hypertension was defined as uncontrolled automated office BP ≥135/85 mm Hg with the use of ≥5 antihypertensive agents, including chlorthalidone and spironolactone. Automated office BP measurements were based on 6 serial readings, done automatically with the use of a BpTRU device unobserved in the clinic. Out-of-office BP measurements were done by 24-hour ambulatory BP monitor. Thirty-four patients were diagnosed with refractory hypertension, of whom 31 had adequate ambulatory BP monitor readings. White-coat effect was present in only 2 patients, or 6.5% of the 31 patients with refractory hypertension, suggesting that white-coat effect is largely absent in patients with refractory hypertension. These findings suggest that white-coat effect is not a common cause of apparent lack of BP control in patients failing maximal antihypertensive treatment. © 2017 American Heart Association, Inc.

  7. Friction measurements of steel on refractory bricks

    International Nuclear Information System (INIS)

    Eiselstein, L.E.

    1981-08-01

    During startup or shutdown of a pool-type LMFBR, substantial shear stresses may arise between the base of the steel reactor vessel and the refractory brick support base. The magnitude of these stresses, which result from differences in thermal expansion, can be estimated if the friction coefficient is known. This report describes experiments to determine friction coefficients between 2 1/4 Cr-1Mo steel and several refractory materials and to examine effects to contact pressure, temperature, sliding velocity, lubricants, and surface condition

  8. Characterization of refractory brick based on local raw material from Lampung Province - Indonesia

    Science.gov (United States)

    Amin, Muhammad; Suryana, Yayat I.; Isnugroho, Kusno; Aji, Bramantyo B.; Birawidha, David C.; Hendronursito, Yusup

    2018-04-01

    Refractories are non-metallic inorganic materials that are difficult to melt at high temperatures and used in high-temperature casting industries. Refractories are classified into their constituent mineral feed stocks, refractories having typical plot properties commonly called fire bricks. In the manufacture of refractory bricks that exist in the market during the use of mangrove materials derived from abroad that is from China. In this research the refractory brick materials used are quartz sand, feldspart, kaolin, bentonite, and ball clay. All materials come from local Lampung Province - Indonesia. The experiment, there are 7 kinds of experimental composition, made of plot shape with size 230 mm, 65 mm in thickness, 114 mm height mould using manual press machine with 10 tons power and burning at 1400°C for 5 hours. Refractory brick product is done by physical test in the form of porosity, specific gravity, compressive strength and XRF and SEM characteristics. The result of XRF characteristic of refractory brick composition of 1 to 5 compared to the refractory brick type SK 34 in the market and the result of composition 1 is a composition close to refractory brick composition type SK 34 namely SiO2 is 54.21 %, Al2O3 is 25.38 % and test Physical of Bulk density is 2.25 g/cm3, porosity is 18.98 % and compressive strength is 325 kg/cm2.

  9. Polymeric precursors method for obtaining pigments based on Inorganic oxides of chromium and iron deposited on TiO2

    International Nuclear Information System (INIS)

    Silva, Everlania M. da; Galvao, Sheila B.; Paskocimas, C.A.

    2011-01-01

    The case study was the use of chromium oxides and iron, as a precursor in the synthesis of inorganic pigments. The synthesis was based on the dissolution of citric acid as a complexing agent, addition of metal oxides, such as ion chromophores; polymerization with ethylene glycol and doping with titanium oxide. Going through pre-calcination, breakdown, calcination at different temperatures (700, 900 and 1100 deg C resulting in pigments: green for pigment and chromium deposited on TiO2, orange for iron on TiO2. The thermal analysis (TG and DTA), evaluated their thermal decompositions, the XRD revealed the formation of crystalline phases such as iron titanate and chrome titanate; SEM showed the formation of hexagonal particles for both oxides. Under the different analysis, one can see the potential stability of pigments and powders, can be proposed its use as pigments in polymers. (author)

  10. Refractory benign esophageal strictures

    Directory of Open Access Journals (Sweden)

    Gopal Goyal

    2016-01-01

    Full Text Available Refractory benign esophageal stricture (RBES is a frequently encountered problem worldwide. These strictures arise from various causes such as corrosive injury, radiation therapy, peptic origin, ablative therapy, and after surgery. Most strictures can be treated successfully with endoscopic dilatation using bougies or balloons, with only a few complications. Those patients who fail after serial dilatation with bougies or balloons will come to the category of refractory strictures. Dilatation combined with intralesional steroid injections can be considered for peptic strictures, whereas incisional therapy has been demonstrated to be effective for short anastomotic strictures. When these therapeutic options do not resolve the stenosis, stent placement should be considered. Self-bougienage can be proposed to a selected group of patients with a proximal stenosis. Most of the patients of RBES respond to above-mentioned treatment and occasional patient may require surgery as the final treatment option. This review aims to provide a comprehensive approach toward endoscopic management of RBESs based on current literature and personal experience.

  11. Illness identity in young adults with refractory epilepsy.

    Science.gov (United States)

    Luyckx, Koen; Oris, Leen; Raymaekers, Koen; Rassart, Jessica; Moons, Philip; Verdyck, Ludo; Mijnster, Teus; Mark, Ruth E

    2018-03-01

    Refractory epilepsy is an intrusive condition with important implications for daily functioning in emerging and young adulthood. The present study examined the degree to which refractory epilepsy is integrated in one's identity, and examined how such a sense of illness identity was related to health-related quality of life (HRQOL). A total of 121 18- to 40-year-old patients with refractory epilepsy (56.2% women) completed self-report questionnaires assessing the four illness identity states of acceptance, enrichment, engulfment, and rejection (Illness Identity Questionnaire (IIQ)); HRQOL (Quality of Life in Epilepsy Inventory - 31); and seizure frequency and severity (Liverpool Seizure Severity Scale (LSSS)). Illness identity scores were compared with a sample of 191 patients with a nonneurological chronic disease (congenital heart disease). Hierarchical regression analyses were conducted to assess the predictive value of illness identity for HRQOL when simultaneously controlling for demographic and clinical features. Patients with refractory epilepsy scored higher on rejection and engulfment and lower on acceptance when compared with patients with congenital heart disease. Further, seizure severity and number of medication side-effects were positively related to engulfment and negatively to acceptance. Finally, when simultaneously controlling for various demographic and clinical variables, illness identity significantly predicted HRQOL (with engulfment being the strongest and most consistent predictor). The extent to which patients with refractory epilepsy succeed in integrating their illness into their identity may have important implications for HRQOL. Clinicians should be especially attentive for signs that patients feel engulfed by their epilepsy. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Ketogenic diet treatment for pediatric super-refractory status epilepticus.

    Science.gov (United States)

    Appavu, Brian; Vanatta, Lisa; Condie, John; Kerrigan, John F; Jarrar, Randa

    2016-10-01

    We aimed to study whether ketogenic diet (KD) therapy leads to resolution of super-refractory status epilepticus in pediatric patients without significant harm. A retrospective review was performed at Phoenix Children's Hospital on patients with super-refractory status epilepticus undergoing ketogenic diet therapy from 2011 to 2015. Ten children with super-refractory status epilepticus, ages 2-16 years, were identified. 4/10 patients had immune mediated encephalitis, including Rasmussen encephalitis, anti-N-methyl-d-aspartate receptor encephalitis, and post-infectious mycoplasma encephalitis. Other etiologies included Lennox Gastaut Syndrome, non-ketotic hyperglycinemia, PCDH19 and GABRG2 genetic epilepsy, New Onset Refractory Status Epilepticus, and Febrile Infection-Related Epilepsy Syndrome. 4/10 patients' EEG features suggested focal with status epilepticus, and 6/10 suggested generalized with status epilepticus. Median hospital length was 61days and median ICU length was 27days. The median number of antiepileptic medications prior to diet initiation was 3.0 drugs, and the median after ketogenic diet treatment was 3.5 drugs. Median duration of status epilepticus prior to KD was 18days. 9/10 patients had resolution of super-refractory status epilepticus in a median of 7days after diet initiation. 8/9 patients were weaned off anesthesia within 15days of diet initiation, and within 1day of achieving ketonuria. 1/10 patients experienced side effects on the diet requiring supplementation. Most patients achieved resolution of status epilepticus on KD therapy, suggesting it could be an effective therapy that can be utilized early in the treatment of children with super refractory status epilepticus. Copyright © 2016. Published by Elsevier Ltd.

  13. Studies on tempering at different temperatures of the beta phase retained by water quenching in uranium-chromium alloys containing from 0,37 to 4 atoms of chromium percent (1963); Etude du revenu a differentes temperatures de la phase beta retenue par trempe a l'eau dans les alliages uranium-chrome contenant de 0,37 a 4 atomes pour cent de chrome (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Degois, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-15

    The author made a systematic study of the annealing of the beta phase retained by water-quenching in uranium-chromium alloys of concentrations between 0.37 and 4 of chromium percent. It is shown that alloys containing less than 1 atom per cent are transformed at temperatures between room temperature and 250 deg. C according to a bainitic process involving activation energies of the order of 14,500 cal/mole. Alloys containing more than 1 at. per cent are transformed at temperature between 400 and 650 deg. C by way of a germination and growth process involving an activation energy of the order of 33,000 cal/mole. The limit of solubility of chromium in beta uranium plays a fundamental part in the transformations of the alloys. The TTT curves of beta {yields} alpha transformation were drawn by the use of a thermo-dilatometer of very low inertia. The transformation law may be expressed 1 x = exp. (kt){sup n}; x represents the degree of progression of the transformation, k a coefficient dependent on the temperature, and n an exponent depending only on the composition of the alloy. A micrographic and crystallographic study confirmed the results found by dilatometry; in particular it was possible to measure the progression rates of the transformation. (author) [French] L'auteur a fait une etude systematique du revenu de la phase beta retenue par trempe a l'eau dans les alliages uranium-chrome de teneurs comprises entre 0,37 et 4 atomes pour cent de chrome. Il a montre que les alliages qui contiennent moins de 1 atome pour cent de chrome se transforment aux temperatures comprises entre la temperature ordinaire et 250 deg. C selon un processus bainitique mettant en jeu des energies d'activatlon de l'ordre de 14500 cal/mole. Les alliages qui renferment plus de 1 atome pour cent de chrome se transforment aux temperatures comprises entre 400 et 650 deg. C suivant un processus de germination et croissance mettant en jeu une energie d'activation de l'ordre de -33000 cal/mole. La

  14. Refractory metal joining for first wall applications

    International Nuclear Information System (INIS)

    Cadden, C.H.; Odegard, B.C.

    2000-01-01

    The potential use of high temperature coolant (e.g. 900 deg. C He) in first wall structures would preclude the applicability of copper alloy heat sink materials and refractory metals would be potential replacements. Brazing trials were conducted in order to examine techniques to join tungsten armor to high tungsten (90-95 wt%) or molybdenum TZM heat sink materials. Palladium-, nickel- and zirconium-based filler metals were investigated using brazing temperatures ranging from 1000 deg. C to 1275 deg. C. Palladium-nickel and palladium-cobalt braze alloys were successful in producing generally sound metallurgical joints in tungsten alloy/tungsten couples, although there was an observed tendency for the pure tungsten armor material to exhibit grain boundary cracking after bonding. The zirconium- and nickel-based filler metals produced defect-containing joints, specifically cracking and porosity, respectively. The palladium-nickel braze alloy produced sound joints in the Mo TZM/tungsten couple. Substitution of a lanthanum oxide-containing, fine-grained tungsten material (for the pure tungsten) eliminated the observed tungsten grain boundary cracking

  15. Refractory metal joining for first wall applications

    Energy Technology Data Exchange (ETDEWEB)

    Cadden, C.H. E-mail: chcadde@sandia.gov; Odegard, B.C

    2000-12-01

    The potential use of high temperature coolant (e.g. 900 deg. C He) in first wall structures would preclude the applicability of copper alloy heat sink materials and refractory metals would be potential replacements. Brazing trials were conducted in order to examine techniques to join tungsten armor to high tungsten (90-95 wt%) or molybdenum TZM heat sink materials. Palladium-, nickel- and zirconium-based filler metals were investigated using brazing temperatures ranging from 1000 deg. C to 1275 deg. C. Palladium-nickel and palladium-cobalt braze alloys were successful in producing generally sound metallurgical joints in tungsten alloy/tungsten couples, although there was an observed tendency for the pure tungsten armor material to exhibit grain boundary cracking after bonding. The zirconium- and nickel-based filler metals produced defect-containing joints, specifically cracking and porosity, respectively. The palladium-nickel braze alloy produced sound joints in the Mo TZM/tungsten couple. Substitution of a lanthanum oxide-containing, fine-grained tungsten material (for the pure tungsten) eliminated the observed tungsten grain boundary cracking.

  16. Refractory metal joining for first wall applications

    Science.gov (United States)

    Cadden, C. H.; Odegard, B. C.

    2000-12-01

    The potential use of high temperature coolant (e.g. 900°C He) in first wall structures would preclude the applicability of copper alloy heat sink materials and refractory metals would be potential replacements. Brazing trials were conducted in order to examine techniques to join tungsten armor to high tungsten (90-95 wt%) or molybdenum TZM heat sink materials. Palladium-, nickel- and zirconium-based filler metals were investigated using brazing temperatures ranging from 1000°C to 1275°C. Palladium-nickel and palladium-cobalt braze alloys were successful in producing generally sound metallurgical joints in tungsten alloy/tungsten couples, although there was an observed tendency for the pure tungsten armor material to exhibit grain boundary cracking after bonding. The zirconium- and nickel-based filler metals produced defect-containing joints, specifically cracking and porosity, respectively. The palladium-nickel braze alloy produced sound joints in the Mo TZM/tungsten couple. Substitution of a lanthanum oxide-containing, fine-grained tungsten material (for the pure tungsten) eliminated the observed tungsten grain boundary cracking.

  17. Central Diabetes Insipidus in Refractory Antineutrophil Cytoplasmic Antibody-associated Vasculitis.

    Science.gov (United States)

    Ohashi, Keiji; Morishita, Michiko; Watanabe, Haruki; Sada, Ken-Ei; Katsuyama, Takayuki; Miyawaki, Yoshia; Katsuyama, Eri; Narazaki, Mariko; Tatebe, Noriko; Watanabe, Katsue; Kawabata, Tomoko; Wada, Jun

    2017-11-01

    We herein describe two cases of refractory antineutrophil cytoplasmic antibody-associated vasculitis (AAV) complicated with diabetes insipidus (DI) possibly related to hypertrophic pachymeningitis (HP). One patient had microscopic polyangiitis and HP, which were refractory to cyclophosphamide, azathioprine, rituximab, mycophenolate mofetil (MMF), and mizoribine. Remission was finally achieved with the use of etanercept, but DI occurred 5 years later. The other patient had granulomatosis with polyangiitis, which that was refractory to cyclophosphamide, methotrexate, MMF, and rituximab. DI subsequently developed, but was successfully treated with etanercept. Dura mater hypertrophy was macroscopically observed in the latter case.

  18. A Review on Recent Advances on Magnesia-Doloma Refractories by Nano-Technology.

    Directory of Open Access Journals (Sweden)

    Salman Ghasemi-Kahrizsangi

    2017-07-01

    Full Text Available Due to exhibiting an excellent chemical resistance against basic environments at high temperature, good thermal shock resistance, thermodynamic stability in the presence of carbon, and a suitable abrasion resistance, MgO-CaO refractories are widely used in argon-oxygen decarburization furnaces in the metallurgy industry and cement rotary kilns. Furthermore, MgO-CaO refractories are beneficial to removing inclusions from molten steels; thus, they have been considered to be one of the effective refractory types for processing clean steel products. Also, MgO-CaO materials have become one of the attractive steelmaking refractories because of their low cost and high ore reserves.  However, in spite of these primary advantages, the application of MgO-CaO refractories has not been popular due to its tendency to hydration when exposed to the atmosphere.  In world most of MgO-CaO bricks producers used of organic components such as tar, pitch, and peck for produce MgO-CaO refractories. But during the application of these bricks in steel and cement and industrials, they released CO and CO2 gases to air and pollute the atmosphere. For this reason, recently some researcher investigate the effect of additive nanoparticles on MgO-CaO refractories performance. They reported the used of Nano-additive have acceptable results and additive nanoparticles can replace by aforementioned environment contaminating organic compounds. In this study, we reviewed all effort that done for improving the hydration resistance of MgO-CaO refractories by application of Nano-additives with an emphasis on the beneficial the use of additives nanoparticle for reduction of environmental pollution by various industries which used of MgO-CaO refractory bricks.

  19. Refractory Research Group - U.S. DOE, Albany Research Center [Institution Profile

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, James P.

    2004-09-01

    The refractory research group at the Albany Research Center (ARC) has a long history of conducting materials research within the U.S. Bureau of Mines, and more recently, within the U.S. Dept. of Energy. When under the U.S. Bureau of Mines, research was driven by national needs to develop substitute materials and to conserve raw materials. This mission was accomplished by improving refractory material properties and/or by recycling refractories using critical and strategic materials. Currently, as a U.S. Dept of Energy Fossil Energy field site, research is driven primarily by the need to assist DOE in meeting its vision to develop economically and environmentally viable technologies for the production of electricity from fossil fuels. Research at ARC impacts this vision by: • Providing information on the performance characteristics of materials being specified for the current generation of power systems; • Developing cost-effective, high performance materials for inclusion in the next generation of fossil power systems; and • Solving environmental emission and waste problems related to fossil energy systems. A brief history of past refractory research within the U.S. Bureau of Mines, the current refractory research at ARC, and the equipment and capabilities used to conduct refractory research at ARC will be discussed.

  20. New system for vacuum deposition of refractory materials using an atmospheric-pressure inductively coupled plasma

    International Nuclear Information System (INIS)

    Merkle, B.D.; Kniseley, R.N.; Schmidt, F.A.

    1987-01-01

    We have successfully developed a technique utilizing an atmospheric-pressure inductively coupled plasma combined with a low-pressure deposition chamber for deposition of thin films. The equipment and method of operation are discussed. Refractory powders (Nb and Y 2 O 3 ) were injected into the plasma and deposited as Nb and substoichiometric yttrium oxide, YO/sub 1.49/, onto Fe and Cu substrates. The substoichiometric yttrium oxide deposit adhered well to the Fe and Cu substrates, while the Nb deposit adhered well to the Fe only. The Nb deposit on the Cu substrate flaked and peeled probably because of stresses induced from the thermal expansion mismatch between the Nb and Cu. Further studies will be undertaken to better understand the processes occurring in this type of plasma-coating system in order to optimize the instrumental parameters for particular coating applications

  1. Brentuximab Vedotin Treatment for Primary Refractory Hodgkin Lymphoma

    Directory of Open Access Journals (Sweden)

    Hung-Bo Wu

    2013-01-01

    Full Text Available Up to 40% of patients with advanced Hodgkin lymphoma (HL become refractory or relapsed after current standard chemotherapy, among which primary refractory HL confers a particularly poor outcome. With intensive salvage chemotherapy and autologous stem cell transplantation, the long-term remission rate for these patients was only 30%, but more selective treatments with higher therapeutic index are needed. We report the experience of using a new anti-CD30 immunotoxin, brentuximab vedotin, in salvage treatment of a 30-year-old woman with primary refractory Hodgkin lymphoma. The patient presented with SVC syndrome due to the bulky mediastinal tumor and was confirmed to have classical Hodgkin lymphoma, nodular sclerosis type, stage IIIA. The tumor responded to induction chemotherapy transiently, but local progression was noted during subsequent cycles of treatment. Salvage radiotherapy to the mediastinal tumor, obtained no remission but was followed by rapid in-field progression and then lung metastasis. She declined stem cell transplantation and received salvage brentuximab vedotin (BV therapy, which induced dramatic shrinkage of tumor without significant side effects. Serial followup of PET/CT imaging confirmed a rapid and continuous complete remission for 12 months. Although durability of the remission needs further observation, this case illustrates the excellent efficacy of brentuximab vedotin in primary refractory Hodgkin lymphoma.

  2. Testing of the melter lid refractory for the West Valley Demonstration Project (WVDP)

    International Nuclear Information System (INIS)

    Gupta, A.; Jain, V.; Mahoney, J.L.; Holman, T.M.

    1991-01-01

    Monofrax H and Mulfrax 202 refractory were tested for potential application as the melter lid refractory for the WVDP. Resistance to spalling and corrosion by the slurry and offgas salts were primary criteria for selection. Test specimens were subjected to thermal cycling between 450 and 1,100C for five weeks. Visual examination indicated some corrosion but no spalling. SEM/EDS analysis was performed to determine the glass/refractory interface corrosion mechanism. The refractory selection basis will be discussed

  3. On the role of salts for the treatment of wastewaters containing pharmaceuticals by electrochemical oxidation using a boron doped diamond anode

    International Nuclear Information System (INIS)

    Lan, Yandi; Coetsier, Clémence; Causserand, Christel; Groenen Serrano, Karine

    2017-01-01

    Refractory pharmaceuticals remain in biologically treated wastewater and are continuously discharged into aquatic systems due to their limited biodegradability. Electrochemical oxidation is promising for the treatment of such refractory compounds, in particular using a boron doped diamond (BDD) anode. This study investigates the role of salts, such as sulfates and chlorides in the electrochemical treatment of wastewater. The presence of sulfates accelerated the removal of ciprofloxacin and sulfamethoxazole, but had no effect on the oxidation of salbutamol. This comparison highlights the selectivity of the reaction between organics and sulfate radicals. The addition of chlorides into the solution led to a remarkably-faster degradation of ciprofloxacin. However, incomplete mineralization was observed at high current densities due to the significant formation of halogenated organic compounds (AOX). The formation of refractory and toxic compounds such as ClO_4"− and AOX can be limited under the control of (i) applied current intensity and (ii) duration of electrolysis. Electrochemical oxidation of concentrated biologically-treated hospital wastewater investigated the excellent removal of biorefractory pharmaceuticals and confirmed the acceleration effect of salts on pharmaceutical degradation.

  4. Simultaneously Recovering High-Purity Chromium and Removing Organic Pollutants from Tannery Effluent

    Directory of Open Access Journals (Sweden)

    Jie Zong

    2016-01-01

    Full Text Available Chromium pollution is a serious issue because of carcinogenic toxicities of the pollutants and low recovery rate of chromium because of the presence of organic, such as protein and fat. In this work, high recovery rate and high purity of the chromium ion were successfully prepared by the way of acid enzyme, flocculant, and Fenton oxidation. The experiments were characterized by TG, TOC, UV-VIS, and SEM. In the work, the tannery waste chrome liquor was used as experimental material. The results showed that the percentage of reduction of TOC in the tannery waste chrome liquor by method of Fenton oxidation, acid enzyme, and the flocculant was 71.15%, 65.26%, and 22.05%, respectively. Therefore, the organism content of chrome tanning waste liquid was greatly reduced through the pretreatment. And the application experiment showed that the properties and grain surface and fibers of the tanned leather with commercial chromium powder and chrome tanning agent prepared from the chromium waste liquid treated with Fenton are nearly the same.

  5. Effectiveness of botulinum toxin A in treatment of refractory erythromelalgia

    Directory of Open Access Journals (Sweden)

    Kuan-Hsiang Lin

    2013-05-01

    Full Text Available Erythromelalgia is characterized by intense burning pain, erythema, and heat in affected areas after precipitating factors such as warm temperature or stress. It is refractory to treatment in some situations. We describe a woman with adenosquamous cell carcinoma of the lung and medically refractory erythromelalgia. The symptoms of erythromelalgia presented as refractory to any medical treatment. Due to the unresponsive nature of her condition, botulinum toxin type A (onabotulinumtoxin A was injected over both of her cheeks, periodically for six cycles. Her symptoms responded dramatically to subcutaneous and intradermal injection of botulinum toxin type A. Repetitive injection demonstrated consistent and reproducible responses, and the efficacy was maintained for approximately 1 month. No adverse effects or complications were noted. Botulinum toxin type A might be safe and effective as an alternative treatment for refractory erythromelalgia, but further large-scale studies are required.

  6. Theoretical and practical aspects about corrosion of refractories used in steel metallurgy: part 3: characterization of commercial refractories; Aspectos teoricos e praticos sobre a corrosao de refratarios utilizados na metalurgia: caracterizacao de refratarios comerciais

    Energy Technology Data Exchange (ETDEWEB)

    Braganca, S.R., E-mail: saulorb@ufrgs.br [Universidade Federal do Rio Grande Sul (DEMAT/UFRGS), RS (Brazil)

    2012-07-01

    In this study, it was reviewed the main aspects found in the literature about refractories corrosion, evaluating the feasibility of certain tests and relating them with experimental results. The physical properties and microstructure of commercial refractories were analyzed, considering the differences between them and the quality implications and probable life of the refractory. Thus, it was studied the various types of refractories used as lining on steel ladle. Magnesia-carbon and doloma-carbon refractories were analyzed, highlighting the differences between them. The examined refractory showed characteristics favoring high resistance to corrosion process, presenting a series of properties to be selected in accordance with industry practice. (author)

  7. Interventional embolization for refractory hyperthyroidism

    International Nuclear Information System (INIS)

    Jiang Guomin; Zhang Yunping; Chen Yaxian; Zhao Jinwei; Yang Weihuai; Chen Jinluo

    2001-01-01

    Objective: To evaluate the clinical effects of the thyroid artery embolization for refractory hyperthyroidism. Methods: Super selective catheterization and interventional embolization of thyroid superior and inferior arteries were performed with PVA microspheres and Gelfoam particles. Changes of function and size of thyroid were investigated after embolization. Results: The procedures were succeeded in all 21 patients. Followed up by 3-12 months, serum level of thyroid hormones dropped significantly (median FT 3 from 17.1 pmol/L to 7.44 pmol/L, median FT 4 from 51.1 pmol/L to 23.3 pmol/L, P< 0.01). The size of thyroid glands decreased remarkably. Symptoms of hyperthyroidism were controlled in 4 patients and were effectively controlled through low dose antithyroid medication in 17 patients. No serious complications occurred. Conclusions: Thyroid artery embolization is a new safe and effective method for refractory hyperthyroidism

  8. Establishment of Wear Resistant HVOF Coatings for 50CrMo4 Chromium Molybdenum Alloy Steel as an Alternative for Hard Chrome Plating

    Science.gov (United States)

    Karuppasamy, S.; Sivan, V.; Natarajan, S.; Kumaresh Babu, S. P.; Duraiselvam, M.; Dhanuskodi, R.

    2018-05-01

    High cost imported components of seamless steel tube manufacturing plants wear frequently and need replacement to ensure the quality of the product. Hard chrome plating, which is time consuming and hazardous, is conventionally used to restore the original dimension of the worn-out surface of the machine components. High Velocity Oxy-Fuel (HVOF) thermal spray coatings with NiCrBSi super alloy powder and Cr3C2 NiCr75/25 alloy powder applied on a 50CrMo4 (DIN-1.7228) chromium molybdenum alloy steel, the material of the wear prone machine component, were evaluated for use as an alternative for hard chrome plating in this present work. The coating characteristics are evaluated using abrasive wear test, sliding wear test and microscopic analysis, hardness test, etc. The study results revealed that the HVOF based NiCrBSi and Cr3C2NiCr75/25 coatings have hardness in the range of 800-900 HV0.3, sliding wear rate in the range of 50-60 µm and surface finish around 5 microns. Cr3C2 NiCr75/25 coating is observed to be a better option out of the two coatings evaluated for the selected application.

  9. Efficacy of infliximab in refractory posterior uveitis in Behcet's disease patients

    OpenAIRE

    Ayman K. El Garf; Amira A. Shahin; Sherif A. Shawky; Mohammed A. Azim; Dina A. Effat; Sherry K. Abdelrahman

    2018-01-01

    Aim of the work: Ocular manifestations are the main cause of morbidity in Behcet's disease (BD). Infliximab (IFX), a chimeric monoclonal antibody directed against tumor necrosis factor-alpha, may be efficient in refractory uveitis due to BD. The aim of this study was to assess the efficacy and safety of IFX in the treatment of patients with BD-associated refractory posterior uveitis (PU). Patient and Methods: Twenty patients with refractory Behcet's PU received IFX therapy as intravenous infu...

  10. Study of aluminium oxide from high-alumina refractory ceramics by ...

    Indian Academy of Sciences (India)

    Wintec

    Keywords. Ceramics; aluminium oxide; X-ray diffraction; scanning electron microscopy; thermolumi- nescence. ... and ruby, consists of a slightly distorted hexagonal O. 2– .... a very complex structure consisting of a broad distribu- .... Imax (a.u.).

  11. Ketogenic diet in 3 cases of childhood refractory status epilepticus

    DEFF Research Database (Denmark)

    Sort, Rune; Born, Alfred P; Pedersen, Karen N.

    2013-01-01

    Refractory status epilepticus (RSE) in children is associated with a significant risk of death or neurological morbidity. Recently attention has been drawn to the ketogenic diet (KD) as an acute treatment, as it has shown promise in controlling seizures in otherwise refractory status epilepticus...

  12. Super Refractory Status Epilepticus

    African Journals Online (AJOL)

    user

    et al did retrospective cohort study from 1 January st. 1994 to 31 March 1998 at Presbyterian Medical. Centre in Columbia, to determine the frequency, risk factors and impact on the outcome of RSE. They found out that 69% of seizures recurred after. Key Words: Super refractory status epilepticus, Zambia. Medical Journal of ...

  13. Process technology - rare and refractory metals

    International Nuclear Information System (INIS)

    Gupta, C.K.; Bose, D.K.

    1989-01-01

    India has fairly rich resreves of rare and refractory metals. Abundant sources of ilmenite, rutile, zircon and rare earths are found in the placer deposits of the southern and eastern coasts of the country. Columbite-tantalite occur in mica and the mining belts of Bihar and cassiterite deposits are found in Bastar (Madhya Pradesh). Vanadium as a minor associate occurs in bauxites and in the vast deposits of titaniferrous magnetites. Over the years, research and development and pilot plant works in many research organisations in India have built up a sound technological base in the country for process metallurgy of many refractory and rare earth metals starting from their indigenous sources. The present paper provides a comprehensive view of the developments that have taken place till now on the processing of various refractory and rare earth metals with particular reference to the extensive work carried out at the Department of Atomic Energy. The coverage includes mineral benification separation of individual elements, preparation of pure intermediates, techniques of reduction to metal and final purification. The paper also reviews some of the recent developments that have been taken place in these fields and the potential application of these metals in the foreseeable future. (author). 22 refs., 18 fi g., 7 tabs

  14. Reuse of ultrafine mineral wool production waste in the manufacture of refractory concrete.

    Science.gov (United States)

    Stonys, R; Kuznetsov, D; Krasnikovs, A; Škamat, J; Baltakys, K; Antonovič, V; Černašėjus, O

    2016-07-01

    The paper deals with the mineral wool production waste (cupola dust - CD), presents CD characterization and aims to reuse CD in production of refractory concrete with calcium aluminate cement. The study of CD covers its chemical, phase and thermal analyses along with the morphological study and determination of particles size distribution. Zeta-potential, electrical conductivity and pH values of CD suspension are presented in the paper as well. Commercial microsilica additive in refractory concrete has been replaced with cupola dust. Compositions of refractory concrete have been prepared by incorporating 1%, 2% and 3% of CD. The bulk density, ultrasonic wave velocity, cold crushing strength and thermal shock resistance of the created refractory concrete have been determined. Based on experimental results, it has been found that cupola dust may be used for the production of refractory concrete. The environmental impact related to the CD reuse in refractory concrete production has been evaluated as well. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. When myasthenia gravis is deemed refractory: clinical signposts and treatment strategies

    Science.gov (United States)

    Mantegazza, Renato; Antozzi, Carlo

    2018-01-01

    The prognosis for patients with myasthenia gravis (MG) has improved significantly over the past half century, including substantial reductions in mortality and morbidity. However, approximately 10% of patients fails to respond adequately to current therapies and are considered treatment refractory, or treatment intolerant, and up to 80% have disease that fails to achieve complete stable remission. Although patients with autoantibodies to muscle-specific tyrosine kinase (anti-MuSK positive) are more likely to become treatment refractory than those with autoantibodies to the acetylcholine receptor (anti-AChR positive), each of these serotypes is substantially represented in the refractory MG population. Other risk factors for becoming treatment refractory include history of thymoma or thymectomy and female sex. A modified treatment algorithm for MG is proposed: patients who have disease that fails to respond to the stepwise approach to therapy, are treatment intolerant, or who require chronic rescue measures despite ongoing therapy, should be considered treatment refractory and emerging therapies should be considered. Three emerging monoclonal antibody-based therapies are discussed: the anti-B-cell agent rituximab; the terminal complement activation inhibitor eculizumab; and belimumab, which targets B-cell activating factor. Increased understanding of molecular pathophysiology and accurate antibody subtyping in MG should lead to the use of new therapeutic agents and successful management of treatment-refractory patients. PMID:29403543

  16. Refractory organic substances in the environment

    National Research Council Canada - National Science Library

    Frimmel, F. H

    2002-01-01

    ... and its Quality Control in Fractions of Refractory Organic Substances and the Corresponding Original Water Samples 39 Introduction 39 Description of Analytical Methods 41 Sample Treatment 41 Fl...

  17. Evaluation of Alternative Refractory Materials for the Main Flame Deflectors at KSC Launch Complexes

    Science.gov (United States)

    Calle, Luz Marina; Trejo, David; Rutkowsky, Justin

    2006-01-01

    The deterioration of the refractory materials used to protect the KSC launch complex steel base structures from the high temperatures during launches results in frequent and costly repairs and safety hazards. KSC-SPEC-P-0012, Specification for Refractory Concrete, is ineffective in qualifying refractory materials. This study of the specification and of alternative refractory materials recommends a complete revision of the specification and further investigation of materials that were found to withstand the environment of the Solid Rocket Booster main flame deflector better than the refractory materials in current use in terms of compressive strength, tensile strength, modulus of rupture, shrinkage, and abrasion.

  18. Nanoscale investigation of the degradation mechanism of a historical chrome yellow paint by quantitative electron energy loss spectroscopy mapping of chromium species.

    Science.gov (United States)

    Tan, Haiyan; Tian, He; Verbeeck, Jo; Monico, Letizia; Janssens, Koen; Van Tendeloo, Gustaaf

    2013-10-18

    Getting the picture: The investigation of 100 year old chrome yellow paint by transmission electron microscopy and spectroscopy has led to the identification of four types of core-shell particles. This nanoscale investigation has allowed a mechanism to be proposed for the darkening of some bright yellow colors in Van Gogh's paintings (e.g. in Falling leaves (Les Alyscamps), 1888). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. A comparative view of radiation, photo and photocatalytically induced oxidation of water pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Getoff, N [Institute for Theoretical Chemistry and Radiation Chemistry, Univ. of Vienna, Vienna (Austria)

    1997-10-01

    Water resources are presently overloaded with biologically resistant (refractory) pollutants. Several oxidation methods have been developed for their degradation, the most efficient of which is irradiation treatment, particularly that based on e-beam processing in the presence of O{sub 2}/O{sub 3}. The next-best method is photoinduced pollutant oxidation with VUV- and/or UV-light, using H{sub 2}O{sub 2} or H{sub 2}O{sub 2}/O{sub 3} as an additional source of OH radicals. The photocatalytic method, using e.g. TiO{sub 2} as a catalyst in combination with oxidation agents such as H{sub 2}O{sub 2} or H{sub 2}O{sub 2}/O{sub 3}, is also recommended. The suitability of these three methods is illustrated by examples and they are briefly discussed and compared on the basis of the energy consumption and efficiency. Other methods, such as ozone treatment, the photo-Fenton process, ultrasonic and electrochemical treatments, as well as the well known biological process and thermal oxidation of refractory pollutants, are briefly mentioned. (author). 36 refs, 9 figs, 3 tabs.

  20. Explosive compaction of aluminum oxide modified by multiwall carbon nanotubes

    Science.gov (United States)

    Buzyurkin, A. E.; Kraus, E. I.; Lukyanov, Ya L.

    2018-04-01

    This paper presents experiments and numerical research on explosive compaction of aluminum oxide powder modified by multiwall carbon nanotubes (MWCNT) and modeling of the stress state behind the shock front at shock loading. The aim of this study was to obtain a durable low-porosity compact sample. The explosive compaction technology is used in this problem because the aluminum oxide is an extremely hard and refractory material. Therefore, its compaction by traditional methods requires special equipment and considerable expenses.

  1. Therapeutic burst-suppression coma in pediatric febrile refractory status epilepticus.

    Science.gov (United States)

    Lin, Jainn-Jim; Chou, Cheng-Che; Lan, Shih-Yun; Hsiao, Hsiang-Ju; Wang, Yu; Chan, Oi-Wa; Hsia, Shao-Hsuan; Wang, Huei-Shyong; Lin, Kuang-Lin

    2017-09-01

    Evidence for the beneficial effect of therapeutic burst-suppression coma in pediatric patients with febrile refractory status epilepticus is limited, and the clinical outcomes of this treatment strategy are largely unknown. Therefore, the aim of this study was to explore the outcomes of therapeutic burst-suppression coma in a series of children with febrile refractory status epilepticus. We retrospectively reviewed consecutive pediatric patients with febrile refractory status epilepticus admitted to our pediatric intensive care unit between January 2000 and December 2013. The clinical characteristics were analyzed. Thirty-five patients (23 boys; age range: 1-18years) were enrolled, of whom 28 (80%) developed super-refractory status epilepticus. All of the patients received the continuous administration of intravenous antiepileptic drugs for febrile refractory status epilepticus, and 26 (74.3%) achieved therapeutic burst-suppression coma. All of the patients received mechanical ventilatory support, and 26 (74.3%) received inotropic agents. Eight (22.9%) patients died within 1month. The neurologically functional outcomes at 6months were good in six (27.3%) of the 22 survivors, of whom two returned to clinical baseline. The patients with therapeutic burst-suppression coma were significantly associated with hemodynamic support than the patients with electrographic seizures control (p=0.03), and had a trend of higher 1-month mortality rate, worse 6months outcomes, and a longer duration of hospitalization. Our results suggest that therapeutic burst-suppression coma to treat febrile refractory status epilepticus may lead to an increased risk of hemodynamic instability and a trend of worse outcomes. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  2. Zirconium determination in refractories (gravimetric method)

    International Nuclear Information System (INIS)

    Capiotto, N.; Narahashi, Y.; Perish, P.G.; Souza, J.R. de

    1991-01-01

    A gravimetric method for zirconium determination in refractories is described. X-ray fluorescence analysis is also employed in this experiment and considerations about interfering elements are presented. (M.V.M.)

  3. Neurobiochemical mechanisms of a ketogenic diet in refractory epilepsy

    Directory of Open Access Journals (Sweden)

    Patricia Azevedo de Lima

    2014-12-01

    Full Text Available A ketogenic diet is an important therapy used in the control of drug-refractory seizures. Many studies have shown that children and adolescents following ketogenic diets exhibit an over 50% reduction in seizure frequency, which is considered to be clinically relevant. These benefits are based on a diet containing high fat (approximately 90% fat for 24 months. This dietary model was proposed in the 1920s and has produced variable clinical responses. Previous studies have shown that the mechanisms underlying seizure control involve ketone bodies, which are produced by fatty acid oxidation. Although the pathways involved in the ketogenic diet are not entirely clear, the main effects of the production of ketone bodies appear to be neurotransmitter modulation and antioxidant effects on the brain. This review highlights the impacts of the ketogenic diet on the modulation of neurotransmitters, levels of biogenic monoamines and protective antioxidant mechanisms of neurons. In addition, future perspectives are proposed.

  4. Applications of radioisotopes for studying refractory wear-out in Bhilai Steel Plant

    International Nuclear Information System (INIS)

    Dubey, R.S.; Bose, U.P.; Shipstone, A.J.

    1979-01-01

    In Bhilai Steel Plant, investigations were carried out to study the refractory wear-out of (i) hearth bottom of blast furnaces, (ii) roof of open hearth furnaces, and (iii) hot metal mixer lining, by using radioisotope tracer techniques with a view to evaluate the life of the refractory lining at various locations and to help in planning its timely hot and cold repairs. The life of the refractory lining has the effective bearing on the overall production and hence on the economy of the plant. The two radiometric methods employed for studying the erosion of the refractory lining, by using isotope inserted bricks at various positions without damaging the lining are (i) based on recording the penetration of gamma rays emitting from the radioactive isotopes inserted at definite points of the brick lining and, (ii) by detecting the radioactivity of the pig iron or steel arising due to washing away of the respective radioactive isotopes previously inserted in the lining. In hot mixers also radioisotope sources were placed in the critical location of refractory lining and the washing out of radioisotope due to refractory brick wear out was detected by radiogauging at site. It has been found that radiotracer technique with periodic radiogauging is very useful method for tracing the radioisotope source if more than one refractory brick with isotope is placed, as in the case of open hearth furnaces. The results of radioanalysis revealed that radioactivity coming alongwith hot metal steel has been far below the permissible limit of concentration i.e. 20 micro-curie per ton of metal. Further, during dismantling of the residual refractory lining of open hearth furnaces or hot metal mixers, bricks containing radioisotopes have been successfully retrieved for safe disposal. (auth.)

  5. Fragmentation process of vitrified ceramic waste (VCW) aiming its incorporation in silico-aluminous refractory concrete for production of refractory bricks

    International Nuclear Information System (INIS)

    Gomes, L.B.; Brandalise, R.N.; Santos, V. dos; Bergmann, C.P.

    2012-01-01

    Ceramic industry generates large amounts of waste, usually disposed in landfills. Reuse could minimize their generation and provides sustainable solutions. However, the energy cost of grinding these waste becomes a hindrance to their reuse. This work aims to obtain particle sizes of vitrified ceramic waste (VCW) using a fast, efficient and low cost fragmentation process as well as its use in refractory concrete. The results shows a wide range of particle size of VCW, which can be used as a promising source of raw material for production of refractory concrete. (author)

  6. Depression in patients with refractory temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Eleonora Borges Gonçalves

    2011-10-01

    Full Text Available OBJECTIVE: To evaluate the comorbidity of depressive disorders in patients with refractory temporal lobe epilepsy (TLE. METHOD: We evaluated 25 consecutive patients with refractory TLE (16 women and 9 men, using semi-structured psychiatric interviews, according to the International Classification of Diseases (ICD-10, and the Beck Depression Inventory. RESULTS: Seventeen of 25 patients (68% had depressive disorder: 6 with dysthymia, three with major depressive episodes and 8 with recurrent depressive disorders. Two (8% were diagnosed with mixed anxiety and depression. Only 5 of 17 patients (29.4% were previously diagnosed with depressive disorder and received prior antidepressant treatment. Duration of epilepsy was significantly higher in patients with depressive disorder (p=0.016, but there was no relationship between depression and seizure frequency. CONCLUSION: This study confirmed that depressive disorders are common and underdiagnosed in patients with TLE refractory to AEDs. Patients with longer duration of epilepsy are at higher risk of having depression.

  7. Alkali metal-refractory metal biphase electrode for AMTEC

    Science.gov (United States)

    Williams, Roger M. (Inventor); Bankston, Clyde P. (Inventor); Cole, Terry (Inventor); Khanna, Satish K. (Inventor); Jeffries-Nakamura, Barbara (Inventor); Wheeler, Bob L. (Inventor)

    1989-01-01

    An electrode having increased output with slower degradation is formed of a film applied to a beta-alumina solid electrolyte (BASE). The film comprises a refractory first metal M.sup.1 such as a platinum group metal, suitably platinum or rhodium, capable of forming a liquid or a strong surface adsorption phase with sodium at the operating temperature of an alkali metal thermoelectric converter (AMTEC) and a second refractory metal insoluble in sodium or the NaM.sup.1 liquid phase such as a Group IVB, VB or VIB metal, suitably tungsten, molybdenum, tantalum or niobium. The liquid phase or surface film provides fast transport through the electrode while the insoluble refractory metal provides a structural matrix for the electrode during operation. A trilayer structure that is stable and not subject to deadhesion comprises a first, thin layer of tungsten, an intermediate co-deposited layer of tungsten-platinum and a thin surface layer of platinum.

  8. Prognostic Factors for Refractory Status Epilepticus

    Directory of Open Access Journals (Sweden)

    J. Gordon Millichap

    2013-03-01

    Full Text Available Researchers at the Mayo Clinic, Rochester, MN studied the outcome and identified prognostic factors for refractory status epilepticus (RSE in 54 adult patients, median age 52 years [range 18-93].

  9. Refractory disease in autoimmune diseases

    NARCIS (Netherlands)

    Vasconcelos, Carlos; Kallenberg, Cees; Shoenfeld, Yehuda

    Refractory disease (RD) definition has different meanings but it is dynamic, according to knowledge and the availability of new drugs. It should be differentiated from severe disease and damage definitions and it must take into account duration of adequate therapy and compliance of the patient. It

  10. Chemical analysis of refractories by plasma spectrometry

    International Nuclear Information System (INIS)

    Coutinho, C.A.

    1990-01-01

    X-ray spectrometry has been, since the last two or three decades, the traditional procedure for the chemical analysis of refractories, due to its high degree of accuracy and speed to produce analytical results. An interesting alternative to X-ray fluorescence is provided by the Inductively Coupled Plasma Spectrometry technique, for those laboratories where wet chemistry facilities are already available or process control is not required at high speed, or investiment costs have to be low. This paper presents results obtained by plasma spectroscopy for the analysis of silico - aluminous refractories, showing calibration curves, precion and detection limits. Considerations and comparisons with X-ray fluorescence are also made. (author) [pt

  11. Development of electro fused aggregates for use in refractories for the burning zone of cement kilns

    International Nuclear Information System (INIS)

    Ferreira, Luis Leonardo Horne Curimbaba

    2006-01-01

    Electro fused aggregates are largely used in refractory production due to the better performance reached when they are employed. In this work electro fused aggregates were designed for application in refractories for the burning zone of cement kilns. Initially reaction evaluation was conducted aiming the identification of the most prone refractory systems when single refractory phases react with Portland cement phases at high temperatures. In the next step, raw materials of the best refractory systems were electro fused to generate different aggregate compositions. The electro fused aggregates properties were evaluated and the classified ones were used to produce refractory bricks for the burning zone of cement kilns. General characteristics of these bricks were measured and compared with a standard magnesia-spinel refractory. Aggregates of the system Mg O - TiO 2 - Ca O, more specifically aggregates belonged to the compatibility triangle Mg O - Mg 2 TiO 4 - CaTiO 3 , showed suitable characteristics for development of refractories for the burning zone cement kilns. (author)

  12. Zirconium determination in refractories (gravimetric method)

    International Nuclear Information System (INIS)

    Capiotto, N.; Narahashi, Y.; Perish, C.G.; Souza, J.R.

    1991-01-01

    The zirconium determination in refractories is described, consisting in two separation methods for eliminating the interferences. The formatted product is calcined at 1100 0 C and determined gravimetrically as Zr P z 07. (author)

  13. Genetics of refractoriness to Plasmodium falciparum in the mosquito Anopheles stephensi

    NARCIS (Netherlands)

    Feldmann, A.M.; Gemert, Geert-Jan van; Vegte-Bolmer, Marga G. van de; Jansen, Ritsert C.

    1998-01-01

    We previously selected a line of the malaria vector mosquito Anopheles stephensi refractory (resistant) to the human malaria parasite Plasmodium falciparum, using in vitro infections with P. falciparum gametocytes. This report presents data on the genetic background of refractoriness. The results of

  14. Productivity Costs in Patients with Refractory Chronic Rhinosinusitis

    Science.gov (United States)

    Rudmik, Luke; Smith, Timothy L.; Schlosser, Rodney J.; Hwang, Peter H.; Mace, Jess C.; Soler, Zachary M.

    2014-01-01

    Objective Disease-specific reductions in patient productivity can lead to substantial economic losses to society. The purpose of this study was to: 1) define the annual productivity cost for a patient with refractory chronic rhinosinusitis (CRS) and 2) evaluate the relationship between degree of productivity cost and CRS-specific characteristics. Study Design Prospective, multi-institutional, observational cohort study. Methods The human capital approach was used to define productivity costs. Annual absenteeism, presenteeism, and lost leisure time was quantified to define annual lost productive time (LPT). LPT was monetized using the annual daily wage rates obtained from the 2012 US National Census and the 2013 US Department of Labor statistics. Results A total of 55 patients with refractory CRS were enrolled. The mean work days lost related to absenteeism and presenteeism was 24.6 and 38.8 days per year, respectively. A total of 21.2 household days were lost per year related to daily sinus care requirements. The overall annual productivity cost was $10,077.07 per patient with refractory CRS. Productivity costs increased with worsening disease-specific QoL (r=0.440; p=0.001). Conclusion Results from this study have demonstrated that the annual productivity cost associated with refractory CRS is $10,077.07 per patient. This substantial cost to society provides a strong incentive to optimize current treatment protocols and continue evaluating novel clinical interventions to reduce this cost. PMID:24619604

  15. Productivity costs in patients with refractory chronic rhinosinusitis.

    Science.gov (United States)

    Rudmik, Luke; Smith, Timothy L; Schlosser, Rodney J; Hwang, Peter H; Mace, Jess C; Soler, Zachary M

    2014-09-01

    Disease-specific reductions in patient productivity can lead to substantial economic losses to society. The purpose of this study was to: 1) define the annual productivity cost for a patient with refractory chronic rhinosinusitis (CRS) and 2) evaluate the relationship between degree of productivity cost and CRS-specific characteristics. Prospective, multi-institutional, observational cohort study. The human capital approach was used to define productivity costs. Annual absenteeism, presenteeism, and lost leisure time was quantified to define annual lost productive time (LPT). LPT was monetized using the annual daily wage rates obtained from the 2012 U.S. National Census and the 2013 U.S. Department of Labor statistics. A total of 55 patients with refractory CRS were enrolled. The mean work days lost related to absenteeism and presenteeism were 24.6 and 38.8 days per year, respectively. A total of 21.2 household days were lost per year related to daily sinus care requirements. The overall annual productivity cost was $10,077.07 per patient with refractory CRS. Productivity costs increased with worsening disease-specific QoL (r = 0.440; p = 0.001). Results from this study have demonstrated that the annual productivity cost associated with refractory CRS is $10,077.07 per patient. This substantial cost to society provides a strong incentive to optimize current treatment protocols and continue evaluating novel clinical interventions to reduce this cost. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  16. Refractory metal based superalloys

    International Nuclear Information System (INIS)

    Alonso, Paula R.; Vicente, Eduardo E.; Rubiolo, Gerardo H.

    1999-01-01

    Refractory metals are looked as promising materials for primary circuits in fission reactors and even as fusion reactor components. Indeed, superalloys could be developed which take advantage of their high temperature properties together with the benefits of a two- phase (intermetallic compound-refractory metal matrix) coherent structure. In 1993, researchers of the Office National d'Etudes et de Recherches Aerospatiales of France reported the observation of such a coherent structure in the Ta-Ti-Zr-Al-Nb-Mo system although the exact composition is not reported. The intermetallic compound would be Ti 2 AlMo based. However, the formation of this compound and its possible coexistence with a disordered bcc phase in the ternary system Ti-Al-Mo is a controversial subject in the related literature. In this work we develop a technique to obtain homogeneous alloys samples with 50 Ti-25 Al-25 Mo composition. The resulting specimens were characterized by optical and electronic metallography (SEM), microprobe composition measurements (EPMA) and X-ray diffraction (XRD) analyses. The results show the evidence for a bcc (A2→B2) ordering reaction in the Ti-Al-Mo system in the 50 Ti-25 Al-25 Mo composition. (author)

  17. Surface enrichment with chrome and nitriding of IF steel under an abnormal glow discharge; Enriquecimento superficial com cromo e nitretacao do aco IF em descarga eletrica em regime anormal

    Energy Technology Data Exchange (ETDEWEB)

    Meira, S.R.; Borges, P.C., E-mail: sabrina.r.meira@gmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Grupo de Materiais; Bernardelli, E.A. [Instituto Federal do Parana (IFPR), Paranagua, PR (Brazil). Laboratorio de Materiais

    2014-07-01

    The objective of this work is to evaluate the influence of surface enrichment of IF steel with chrome, and nitriding, the formation of the nitrided layer. Thus, IF steel samples were subjected to surface enrichment process, using 409 stainless steel as a target for sputtering, followed by plasma nitriding, both under a dc abnormal glow discharge. The enrichment treatment was operated at 1200 ° C for 3h. The nitriding treatment was operated at 510 ° C for 2 h. The influence of the treatments on the layers formed was studied through optical microscopy (OM), scan electron microscopy (SEM), X-ray diffraction (XRD) and Vickers microindentation. The results show that the enrichment is effective to enrich the IF surface, furthermore, improves the characteristics of nitriding, comparing nitriding samples to nitriding and enriched, was observed needles of nitrides, as well as a higher hardness, which is associated with the nitrides of chrome, on the nitriding and enriched samples. (author)

  18. PHOTOCATALYTIC REMOVAL OF TR I- AND HEXA-VALENT CHROMIUM IONS FROM CHROME-ELECTROPL ATING WASTEWATER

    Directory of Open Access Journals (Sweden)

    Puangrat Kajitvichyanukul

    2017-11-01

    Full Text Available A novel technique based on photocatalysis was applied to eliminate chromium ions, a toxic hazardous environmental pollutant. The photoreduction of each species of chromium (total, hexavalent, and trivalent chromiums from chrome-electroplating wastewater was investigated using a titanium dioxide suspension under irradiation by a low-pressure mercury lamp. The initial concentration of total chromium was 300 mg/l. The applied conditions were the direct photocatalytic reduction process at pH 3.65 and the indirect photocatalytic reduction with added hole scavengers at the same solution pH. Results from both processes were comparatively discussed. Result show that chromium was not efficiently removed by direct photoreduction. In contrast, with the adding of hole scavengers, which were formate ions, the photoreduction of chromium was very favorable. Both hexavalent and trivalent chromiums were efficiently removed. The photocatalytic mechanism is purposed in this study.

  19. Spectrophotometric determination of zirconium with Chrome Azurol s in aqueous streams of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Ganesh, S.; Velavendan, P.; Pandey, N.K.; Kamachi Mudali, U.; Natarajan, R.

    2014-01-01

    A sensitive and reproducible spectrophotometric method for the determination of zirconium is developed. The method is based on the formation of stable bluish violet colour complex with Chrome Azurol S (CAS) with maximum absorption at 598 nm. The complex formed obeys Beer's law in the range of 1-7 μg/mL. Under optimum conditions, the sensitivity of the proposed method, (i.e. the detection limit), molar absorptivity and Sandell's sensitivity values are 2.42 μg/mL, 3.93 x10 3 L.Mol -1 .cm -1 and 2.54 x 10 -4 μg/cm 2 respectively. Relative standard deviation is less than 2% and correlation coefficient is 0.997. The present method is highly sensitive, selective, rapid and simple. It can be applied for the direct determination of zirconium in environmental, industrial, water and nuclear reprocessing samples. (author)

  20. Felbamate in an adult population with severe refractory epilepsy.

    LENUS (Irish Health Repository)

    Kearney, H

    2011-04-05

    Felbamate (FBM) is efficacious in treating patients with refractory epilepsy but was withdrawn due to cases of aplastic anaemia, hepatic failure and five reported deaths. FBM is currently used in specialist centres and is only being used in one Irish centre to date. This papers aim is to review the efficacy and safety experience of FBM in Irish adult patients with refractory epilepsy. A retrospective chart review was done on patients\\' medical records. Patients were subdivided into responders and non responders based on change in seizure frequency and side effects were recorded for all. Of the 13 patients on FBM nine patients responded to FBM, four patients did not. FBM is a safe and efficacious alternative in an Irish adult population with refractory epilepsy. However close monitoring is still required given the potential fatal side effects that are possible with this anticonvulsant.

  1. Performance testing of refractory alloy-clad fuel elements for space reactors

    International Nuclear Information System (INIS)

    Dutt, D.S.; Cox, C.M.; Karnesky, R.A.; Millhollen, M.K.

    1985-01-01

    Two fast reactor irradiation tests, SP-1 and SP-2, provide a unique and self-consistent data set with which to evaluate the technical feasibility of potential fuel systems for the SP-100 space reactor. Fuel pins fabricated with leading cladding candidates (Nb-1Zr, PWC-11, and Mo-13Re) and fuel forms (UN and UO 2 ) are operated at temperatures typical of those expected in the SP-100 design. The first US fast reactor irradiated, refractory alloy clad fuel pins, from the SP-1 test, reached 1 at. % burnup in EBR-II in March 1985. At that time selected pins were discharged for interim examination. These examinations confirmed the excellent performance of the Nb-1Zr clad uranium oxide and uranium nitride fuel elements, which are the baseline fuel systems for two SP-100 reactor concepts

  2. Ten patients with refractory status epilepticus in an intensive care department

    NARCIS (Netherlands)

    ter Maaten, JC; van Schijndel, RJM; Heimans, JJ; Schreuder, WO

    1998-01-01

    Status epilepticus (SE) is a serious disease, associated with a high morbidity and mortality, particularly if refractory to initial therapy. We describe the clinical manifestations and outcome in ten cases with refractory SE admitted to our medical intensive care unit. Three of these selected group

  3. Refractory absence epilepsy associated with GLUT-1 deficiency syndrome.

    LENUS (Irish Health Repository)

    Byrne, Susan

    2011-05-01

    GLUT-1 deficiency syndrome (GLUT-1 DS) is a disorder of cerebral glucose transport associated with early infantile epilepsy and microcephaly. We report two boys who presented with refractory absence epilepsy associated with hypoglycorrhachia, both of whom have genetically confirmed GLUT-1 DS. We propose that these children serve to expand the phenotype of GLUT-1 DS and suggest that this condition should be considered as a cause of refractory absence seizures in childhood.

  4. Treatment of Refractory Idiopathic Supraorbital Neuralgia Using Percutaneous Pulsed Radiofrequency.

    Science.gov (United States)

    Luo, Fang; Lu, Jingjing; Ji, Nan

    2018-02-26

    No ideal therapeutic method currently exists for refractory idiopathic supraorbital neuralgia patients who do not respond to conservative therapy, including medications and nerve blocks. Pulsed radiofrequency is a neuromodulation technique that does not produce sequelae of nerve damage after treatment. However, the efficacy of percutaneous pulsed radiofrequency for the treatment of refractory idiopathic supraorbital neuralgia is still not clear. The purpose of our study was to evaluate the efficacy and safety of pulsed radiofrequency treatment of the supraorbital nerve for refractory supraorbital neuralgia patients. We prospectively investigated the long-term effects of ultrasound-guided percutaneous pulsed radiofrequency in the treatment of 22 refractory idiopathic supraorbital neuralgia patients. A reduction in the verbal pain numeric rating scale score of more than 50% was used as the standard of effectiveness. The effectiveness rates at different time points within 2 years were calculated. After a single pulsed radiofrequency treatment, the effectiveness rate at 1 and 3 months was 77%, and the rates at 6 months, 1 year, and 2 years were 73%, 64%, and 50%, respectively. Except for a small portion of patients (23%) who experienced mild upper eyelid ecchymosis that gradually disappeared after approximately 2 weeks, no obvious complications were observed. In conclusion, the results of our study demonstrate that for patients with refractory idiopathic supraorbital neuralgia, percutaneous pulsed radiofrequency may be an effective and safe treatment choice. © 2018 World Institute of Pain.

  5. Surgical disconnection of patent paraumbilical vein in refractory hepatic encephalopathy.

    Science.gov (United States)

    Ishikawa, Yoshinori; Yoshida, Hiroshi; Mamada, Yasuhiro; Taniai, Nobuhiko; Bando, Koichi; Mizuguchi, Yoshiaki; Kakinuma, Daisuke; Kanda, Tomohiro; Akimaru, Koho; Tajiri, Takashi

    2008-06-01

    Refractory hepatic encephalopathy (HE) frequently develops in patients with cirrhosis and portal-systemic shunt. Recently, patients with refractory HE associated with portal-systemic shunt have been treated with interventional radiology. We describe a promising new treatment for portal-systemic shunt, ligation of the patent paraumbilical vein (PUV) after partial splenic embolization, in patients with refractory HE. Four patients with cirrhosis (3 women and 1 man; mean age, 56 years) and refractory HE due to a patent PUV were studied. Patency of the PUV had recurred in 1 patient after primary occlusion by interventional radiological procedures. The Child-Pugh class was B in 2 patients and C in 2. Before the present treatment, all patients had been hospitalized at least 3 times because of recurrent HE. Partial splenic embolization was performed in all patients to decrease portal venous pressure before surgery. Surgical ligation of the patent PUV was performed under epidural anesthesia. The patent PUV was carefully skeletonized and doubly ligated. Esophageal varices were evaluated with upper gastrointestinal endoscopy before and after surgery. The mean follow-up duration was 15.8 months. After ligation, there were no clinically significant complications. Esophageal varices were unchanged. The serum ammonia level was higher before surgery (162.3 +/- 56.4 mug/dL, mean +/- SD) than after surgery (41.8 +/- 20.2 mug/dL; p=0.0299). No patient had symptoms of HE. Ligation of the patent PUV is an effective treatment for patients with refractory HE.

  6. Bulk Vitrification Performance Enhancement: Refractory Lining Protection Against Molten Salt Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Hrma, Pavel R.; Bagaasen, Larry M.; Schweiger, Michael J.; Evans, Michael B.; Smith, Benjamin T.; Arrigoni, Benjamin M.; Kim, Dong-Sang; Rodriguez, Carmen P.; Yokuda, Satoru T.; Matyas, Josef; Buchmiller, William C.; Gallegos, Autumn B.; Fluegel, Alexander

    2007-08-06

    Bulk vitrification (BV) is a process that heats a feed material that consists of glass-forming solids and dried low-activity waste (LAW) in a disposable refractory-lined metal box using electrical power supplied through carbon electrodes. The feed is heated to the point that the LAW decomposes and combines with the solids to generate a vitreous waste form. This study supports the BV design and operations by exploring various methods aimed at reducing the quantities of soluble Tc in the castable refractory block portion of the refractory lining, which limits the effectiveness of the final waste form.

  7. Comparison of Refractory Performance in Black Liquor Gasifiers and a Smelt Test System

    International Nuclear Information System (INIS)

    Peascoe, RA

    2001-01-01

    Prior laboratory corrosion studies along with experience at the black liquor gasifier in New Bern, North Carolina, clearly demonstrate that serious material problems exist with the gasifier's refractory lining. Mullite-based and alumina-based refractories used at the New Bern facility suffered significant degradation even though they reportedly performed adequately in smaller scale systems. Oak Ridge National Laboratory's involvement in the failure analysis, and the initial exploration of suitable replacement materials, led to the realization that a simple and reliable, complementary method for refractory screening was needed. The development of a laboratory test system and its suitability for simulating the environment of black liquor gasifiers was undertaken. Identification and characterization of corrosion products were used to evaluate the test system as a rapid screening tool for refractory performance and as a predictor of refractory lifetime. Results from the test systems and pl ants were qualitatively similar

  8. Nucleotide sequence of the 3' ends of the double-stranded RNAs of grapevine chrome mosaic nepovirus.

    Science.gov (United States)

    Le Gall, O; Candresse, T; Dunez, J

    1988-02-01

    Attempts were made to label the termini of dsRNAs corresponding to the two genomic RNAs of grapevine chrome mosaic nepovirus (GCMV). It was not possible to label the 5' ends of the dsRNAs with [gamma-32P]ATP, which suggests that a genome-linked protein blocks their 5' ends. Both dsRNA species were labelled at their 3' ends with pCp. The 3'-terminal sequences were determined by 'wandering spot' or by partial enzymic cleavage analysis. One strand (presumably positive) ended in a poly(A) 30 to 50 nucleotides long whereas the other (presumably negative) ended in 3'-ACCUUUUAAAAAG (RNA1) or 3'-ACCUUUUAAUAAAG (RNA2). The sequences resemble closely those complementary to the 5' ends of the RNAs of tomato black ring virus (strain S), which is distantly related to GCMV.

  9. Oral tranexamic acid lightens refractory melasma.

    Science.gov (United States)

    Tan, Aaron Wei Min; Sen, Priya; Chua, Sze Hon; Goh, Boon Kee

    2017-08-01

    Melasma is a common acquired hyperpigmentary disorder, particularly among Asians and Hispanics, but its exact pathomechanism is poorly understood. Tranexamic acid has been found to lighten melasma by interfering with the interaction of melanocytes and keratinocytes by inhibiting the plasminogen/plasmin system. The aim was to evaluate the therapeutic effects of oral tranexamic acid in the treatment of melasma refractory to topical skin-lightening agents. This retrospective study analyses patients with melasma recruited from a tertiary dermatological centre in Singapore between 1 August 2009 and 31 March 2011. The patients chosen had refractory melasma treated with oral tranexamic acid 250 mg twice daily in addition to pre-existing combination topical therapy. Objective assessment using the physician's global assessment and melasma area and severity index (MASI) scores were performed based on a post-hoc analysis of photographic records by three independent physicians. A paired t-test was used to evaluate the changes in the MASI scores pre-therapy and post-treatment. Statistical significance was defined as P tranexamic acid for a mean period of 3.7 ± 0.33 months, in addition to combination topical therapy. Their mean age was 47.2 ± 1.61 years. The mean MASI scores after tranexamic acid treatment (2.7 ± 1.6) were significantly lower (P tranexamic acid can serve as a safe and useful adjunct in the treatment of refractory melasma. © 2016 The Australasian College of Dermatologists.

  10. Clinical features and course of refractory anemia with ring sideroblasts associated with marked thrombocytosis

    Science.gov (United States)

    Broseus, Julien; Florensa, Lourdes; Zipperer, Esther; Schnittger, Susanne; Malcovati, Luca; Richebourg, Steven; Lippert, Eric; Cermak, Jaroslav; Evans, Jyoti; Mounier, Morgane; Raya, José Maria; Bailly, François; Gattermann, Norbert; Haferlach, Torsten; Garand, Richard; Allou, Kaoutar; Besses, Carlos; Germing, Ulrich; Haferlach, Claudia; Travaglino, Erica; Luno, Elisa; Pinan, Maria Angeles; Arenillas, Leonor; Rozman, Maria; Perez Sirvent, Maria Luz; Favre, Bernardine; Guy, Julien; Alonso, Esther; Ahwij, Nuhri; Jerez, Andrés; Hermouet, Sylvie; Maynadié, Marc; Cazzola, Mario; Girodon, François

    2012-01-01

    Background Refractory anemia with ring sideroblasts associated with marked thrombocytosis was proposed as a provisional entity in the 2001 World Health Organization classification of myeloid neoplasms and also in the 2008 version, but its existence as a single entity is contested. We wish to define the clinical features of this rare myelodysplastic/myeloproliferative neoplasm and to compare its clinical outcome with that of refractory anemia with ring sideroblasts and essential thrombocythemia. Design and Methods We conducted a collaborative retrospective study across Europe. Our database included 200 patients diagnosed with refractory anemia with ring sideroblasts and marked thrombocytosis. For each of these patients, each patient diagnosed with refractory anemia with ring sideroblasts was matched for age and sex. At the same time, a cohort of 454 patients with essential thrombocythemia was used to compare outcomes of the two diseases. Results In patients with refractory anemia with ring sideroblasts and marked thrombocytosis, depending on the Janus Kinase 2 V617F mutational status (positive or negative) or platelet threshold (over or below 600×109/L), no difference in survival was noted. However, these patients had shorter overall survival and leukemia-free survival with a lower risk of thrombotic complications than did patients with essential thrombocythemia (P<0.001) but better survival (P<0.001) and a higher risk of thrombosis (P=0.039) than patients with refractory anemia with ring sideroblasts. Conclusions The clinical course of refractory anemia with ring sideroblasts and marked thrombocytosis is better than that of refractory anemia with ring sideroblasts and worse than that of essential thrombocythemia. The higher risk of thrombotic events in this disorder suggests that anti-platelet therapy might be considered in this subset of patients. From a clinical point of view, it appears to be important to consider refractory anemia with ring sideroblasts and

  11. Refractory metal superalloys: Design of yttrium aluminum garnet passivating niobium alloys

    Science.gov (United States)

    Bryan, David

    A systems-based approach, integrating computational modeling with experimental techniques to approach engineering problems in a time and cost efficient manner, was employed to design a Nb-based refractory superalloy for use at 1300°C. Ashby-type selection criteria for both thermodynamic and kinetic parameters were employed to identify a suitable protective oxide for Nb alloys. Yttrium aluminum garnet (YAG) was selected as the most promising candidate for its excellent combination of desirable properties. The alloy microstructural concept was based upon the gamma - gamma' nickel-based superalloys in which the multifunctional gamma' phase serves as both a creep strengthening dispersion and a source of reactive elements for oxide passivation. Candidate ternary Pd-Y-Al and Pt-Y-Al compounds were fabricated and characterized by XRD and DTA. Of the intermetallics studied, only PtYAl had a high enough melting point (1580°C) for use in an alloy operating at 1300°C. The alloy matrix design was based upon Wahl's extension of Wagner's criterion for protective oxidation, requiring a reduction of the product N ODO/DAl by 5 orders of magnitude relative to binary Nb-Al. A thermodynamic and kinetic analysis identified elements with large oxygen affinities as the most beneficial for reducing the magnitude of the quantity NOD O. Construction of a combined thermodynamic and mobility database identified increased Al solubility as the best approach for increasing D Al. Utilizing the thermodynamic and mobility databases, obtained from a combination of model alloys, oxidation experiments, and first principles calculations, theoretical designs predicted the large changes in solubility and transport parameters were achievable. Several prototype alloys were then fabricated and evaluated via oxidation tests at both 1300°C and 1100°C. YAG formation was demonstrated as part of multicomponent oxide scales in the alloys that exhibited the greatest reduction in oxidation rates. The oxidation

  12. Nanostructured refractory thin films for solar applications

    Science.gov (United States)

    Ollier, E.; Dunoyer, N.; Dellea, O.; Szambolics, H.

    2014-08-01

    Selective solar absorbers are key elements of all solar thermal systems. Solar thermal panels and Concentrated Solar Power (CSP) systems aim respectively at producing heat and electricity. In both cases, a surface receives the solar radiation and is designed to have the highest optical absorption (lowest optical reflectivity) of the solar radiation in the visible wavelength range where the solar intensity is the highest. It also has a low emissivity in the infrared (IR) range in order to avoid radiative thermal losses. Current solutions in the state of the art usually consist in deposited interferential thin films or in cermets [1]. Structured surfaces have been proposed and have been simulated because they are supposed to be more efficient when the solar radiation is not normal to the receiving surface and because they could potentially be fabricated with refractory materials able to sustain high operating temperatures. This work presents a new method to fabricate micro/nanostructured surfaces on molybdenum (refractory metal with a melting temperature of 2623°C). This method now allows obtaining a refractory selective surface with an excellent optical selectivity and a very high absorption in the visible range. This high absorption performance was obtained by achieving a double structuration at micro and nano scales thanks to an innovative process flow.

  13. Investigation of the interaction of chrome compounds with blue-green microalgae Spirulina platensis

    International Nuclear Information System (INIS)

    Mosulishvili, L.M.; Belokobyl'skij, A.I.; Kirkesali, E.I.; Frontas'eva, M.V.; Pavlov, S.S.; Aksenova, N.G.

    2002-01-01

    The interaction of CrIII with the cells of blue-green microalgae Spirulina platensis in course of cultivation in a nutrient medium loaded with corresponding chrome compounds is studied. It is shown that the rate of absorption of CrVI ions by spirulina biomass from the nutrient medium is approximately two orders of magnitude lower as compared to that of CrIII ions. At the same time the presence of CrVI in a nutrient medium is accompanied by a significant decrease in the cell growth rate and by deteriorating the quality of spirulina biomass. It is established that at endogenous insertion of CrIII into the biocomplex of spirulina no change in the valence state of chromium in the nutrient medium is observed and the natural properties of the biomass do not change. On the basis of the obtained concentration dependences, the recommended doses of CrIII in the preparation 'Cr-Spirulina' within the ranges of 30-100 μg/g as a food addition, and 200-250 μg/g for a medical preventive treatment are determined. (author)

  14. Long-term evaluation of treatment of chronic, therapeutically refractory tinnitus by neurostimulation

    NARCIS (Netherlands)

    Staal, M. J.; Holm, A. F.; Mooij, J. J. A.; Albers, F. W. J.; Bartels, H.

    2007-01-01

    Objective: Long-term evaluation of treatment of chronic, therapeutically refractory tinnitus by means of chronic electrical stimulation of the vestibulocochlear nerve. Patients: Inclusion criteria were severe, chronic, therapeutically refractory, unilateral tinnitus and severe hearing loss at the

  15. Super-Refractory Status Epilepticus: Report of a Case and Review of the Literature.

    Science.gov (United States)

    Lapenta, Leonardo; Frisullo, Giovanni; Vollono, Catello; Brunetti, Valerio; Giannantoni, Nadia Mariagrazia; Sandroni, Claudio; Di Lella, Giuseppe; Della Marca, Giacomo

    2015-10-01

    Super-refractory status epilepticus (SE; ie, SE continuing or recurring despite 24 hours of general anesthesia) is a severe condition with high percentage of mortality and morbidity. Usually, this condition occurs because of serious brain damage; nevertheless, some patients develop super-refractory SE without identifiable etiology. Although not uncommonly encountered in neurointensive care, scientific data on this condition are still lacking in terms of treatment and prognosis. Herein, we report a case of super-refractory SE with recovery after 50 days, despite electroencephalographic (EEG) and magnetic resonance imaging (MRI) signs traditionally related to poor prognosis. A review of the literature on super-refractory SE is also presented. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  16. Tioguanine in the treatment of refractory coeliac disease--a single centre experience.

    Science.gov (United States)

    Tack, G J; van Asseldonk, D P; van Wanrooij, R L J; van Bodegraven, A A; Mulder, C J

    2012-08-01

    Refractory coeliac disease type I is a complicated form of coeliac disease characterised by primary or secondary resistance to a gluten-free diet with persisting or reoccurring intestinal villous atrophy and symptoms of malabsorption. Besides corticosteroids, azathioprine has been advocated for the treatment of refractory coeliac disease type I. However, tioguanine (TG) might be better tolerated and more efficacious owing to a simpler metabolism towards bioactivation. To evaluate tolerability and effectiveness of the nonconventional thiopurine derivative TG in refractory coeliac disease type I. Refractory coeliac disease type I patients treated with TG between June 2001 and November 2010 with a follow-up period of at least 1 year were included. Adverse events, laboratory values, 6-thioguanine nucleotide concentrations and rates of both clinical and histological response were evaluated at baseline and during follow-up. Twelve adult refractory coeliac disease type I patients were included. The median TG treatment duration was 14 months. Ten patients tolerated TG treatment on the long term, whereas two patients withdrew treatment due to adverse events. No nodular regenerative hyperplasia of the liver was observed. During follow-up clinical and histological response was observed in 83% and 78%, respectively. Corticosteroid dependency decreased by 50%. Tioguanine appears to be a convenient drug for the treatment of refractory coeliac disease type I based on higher histological and similar clinical response rates as compared with historical conventional therapies. © 2012 Blackwell Publishing Ltd.

  17. Refractory, Abrasive and Other Industrial Mineral Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes refractory, abrasive, and other industrial minerals operations in the United States. The data represent commodities covered by the Minerals...

  18. Evaluation of nutritional status in children with refractory epilepsy

    Directory of Open Access Journals (Sweden)

    Testolin G

    2006-04-01

    Full Text Available Abstract Background children affected by refractory epilepsy could be at risk of malnutrition because of feeding difficulties (anorexia, chewing, swallowing difficulties or vomiting and chronic use of anticonvulsants, which may affect food intake and energy metabolism. Moreover, their energy requirement may be changed as their disabilities would impede normal daily activities. The aim of the present study was to evaluate nutritional status, energy metabolism and food intake in children with refractory epilepsy. Methods 17 children with refractory epilepsy (13 boys and 4 girls; mean age 9 ± 3,2 years; Body Mass Index 15,7 ± 3,6 underwent an anthropometric assessment, body composition evaluation by dual-energy X-ray absorptiometry, detailed dietetic survey and measurement of resting energy expenditure by indirect calorimetry. Weight-for-age, height-for-age (stunting and weight-for-height (wasting were estimated compared to those of a reference population of the same age. Results 40% of children were malnourished and 24% were wasted. The nutritional status was worse in the more disabled children. Dietary intake resulted unbalanced (18%, 39%, 43% of total daily energy intake derived respectively from protein, lipid and carbohydrate. Adequacy index [nutrient daily intake/recommended allowance (RDA × 100] was Conclusion many children with refractory epilepsy would benefit from individual nutritional assessment and management as part of their overall care.

  19. Heterogeneous Oxidation of Laboratory-generated Mixed Composition and Biomass Burning Particles

    Science.gov (United States)

    Lim, C. Y.; Sugrue, R. A.; Hagan, D. H.; Cappa, C. D.; Kroll, J. H.; Browne, E. C.

    2016-12-01

    Heterogeneous oxidation of organic aerosol (OA) can significantly transform the chemical and physical properties of particulate matter in the atmosphere, leading to changes to the chemical composition of OA and potential volatilization of organic compounds. It has become increasingly apparent that the heterogeneous oxidation kinetics of OA depend on the phase and morphology of the particles. However, most laboratory experiments to date have been performed on single-component, purely organic precursors, which may exhibit fundamentally different behavior than more complex particles in the atmosphere. Here we present laboratory studies of the heterogeneous oxidation of two more complex chemical systems: thin, organic coatings on inorganic seed particles and biomass burning OA. In the first system, squalane (C30H62), a model compound for reduced OA, is coated onto dry ammonium sulfate particles at various thicknesses (10-20 nm) and exposed to hydroxyl radical (OH) in a flow tube reactor. In the second, we use a semi-batch reactor to study the heterogeneous OH-initiated oxidation of biomass burning particles as a part of the 2016 FIREX campaign in Missoula, MT. The resulting changes in chemical composition are monitored with an Aerodyne High Resolution Time-of-flight Aerosol Mass Spectrometer (AMS) and a soot-particle AMS for the non-refractory and refractory systems, respectively. We show that the heterogeneous oxidation kinetics of these multicomponent particles are substantially different than that of the single-component particles. The oxidation of organic coatings is rapid, undergoing dramatic changes to carbon oxidation state and losing a significant amount of organic mass after relatively low OH exposures (equivalent to several days of atmospheric processing). In the case of biomass burning particles, the kinetics are complex, with different components (inferred by aerosol mass spectrometry) undergoing oxidation at different rates.

  20. A numerical investigation into the influence of the properties of cobalt chrome cellular structures on the load transfer to the periprosthetic femur following total hip arthroplasty.

    Science.gov (United States)

    Hazlehurst, Kevin Brian; Wang, Chang Jiang; Stanford, Mark

    2014-04-01

    Stress shielding of the periprosthetic femur following total hip arthroplasty is a problem that can promote the premature loosening of femoral stems. In order to reduce the need for revision surgery it is thought that more flexible implant designs need to be considered. In this work, the mechanical properties of laser melted square pore cobalt chrome molybdenum cellular structures have been incorporated into the design of a traditional monoblock femoral stem. The influence of incorporating the properties of cellular structures on the load transfer to the periprosthetic femur was investigated using a three dimensional finite element model. Eleven different stiffness configurations were investigated by using fully porous and functionally graded approaches. This investigation confirms that the periprosthetic stress values depend on the stiffness configuration of the stem. The numerical results showed that stress shielding is reduced in the periprosthetic Gruen zones when the mechanical properties of cobalt chrome molybdenum cellular structures are used. This work identifies that monoblock femoral stems manufactured using a laser melting process, which are designed for reduced stiffness, have the potential to contribute towards reducing stress shielding. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  1. Effectiveness of intravenous levetiracetam as an adjunctive treatment in pediatric refractory status epilepticus.

    Science.gov (United States)

    Kim, Jon Soo; Lee, Jeong Ho; Ryu, Hye Won; Lim, Byung Chan; Hwang, Hee; Chae, Jong-Hee; Choi, Jieun; Kim, Ki Joong; Hwang, Yong Seung; Kim, Hunmin

    2014-08-01

    Intravenous levetiracetam (LEV) has been shown to be effective and safe in treating adults with refractory status epilepticus (SE). We sought to investigate the efficacy and safety of intravenous LEV for pediatric patients with refractory SE. We performed a retrospective medical-record review of pediatric patients who were treated with intravenous LEV for refractory SE. Clinical information regarding age, sex, seizure type, and underlying neurological status was collected. We evaluated other anticonvulsants that were used prior to administration of intravenous LEV and assessed loading dose, response to treatment, and any adverse events from intravenous LEV administration. Fourteen patients (8 boys and 6 girls) received intravenous LEV for the treatment of refractory SE. The mean age of the patients was 4.4 ± 5.5 years (range, 4 days to 14.6 years). Ten of the patients were neurologically healthy prior to the refractory SE, and the other 4 had been previously diagnosed with epilepsy. The mean loading dose of intravenous LEV was 26 ± 4.6 mg/kg (range, 20-30 mg/kg). Seizure termination occurred in 6 (43%) of the 14 patients. In particular, 4 (57%) of the 7 patients younger than 2 years showed seizure termination. No immediate adverse events occurred during or after infusions. The current study demonstrated that the adjunctive use of intravenous LEV was effective and well tolerated in pediatric patients with refractory SE, even in patients younger than 2 years. Intravenous LEV should be considered as an effective and safe treatment option for refractory SE in pediatric patients.

  2. Enhancing Surface Finish of Additively Manufactured Titanium and Cobalt Chrome Elements Using Laser Based Finishing

    Science.gov (United States)

    Gora, Wojciech S.; Tian, Yingtao; Cabo, Aldara Pan; Ardron, Marcus; Maier, Robert R. J.; Prangnell, Philip; Weston, Nicholas J.; Hand, Duncan P.

    Additive manufacturing (AM) offers the possibility of creating a complex free form object as a single element, which is not possible using traditional mechanical machining. Unfortunately the typically rough surface finish of additively manufactured parts is unsuitable for many applications. As a result AM parts must be post-processed; typically mechanically machined and/or and polished using either chemical or mechanical techniques (both of which have their limitations). Laser based polishing is based on remelting of a very thin surface layer and it offers potential as a highly repeatable, higher speed process capable of selective area polishing, and without any waste problems (no abrasives or liquids). In this paper an in-depth investigation of CW laser polishing of titanium and cobalt chrome AM elements is presented. The impact of different scanning strategies, laser parameters and initial surface condition on the achieved surface finish is evaluated.

  3. Neuroimaging in refractory epilepsy. Current practice and evolving trends

    Energy Technology Data Exchange (ETDEWEB)

    Ramli, N. [Department of Biomedical Imaging, University Malaya Research Imaging Centre (Malaysia); Rahmat, K., E-mail: katt_xr2000@yahoo.com [Department of Biomedical Imaging, University Malaya Research Imaging Centre (Malaysia); Lim, K.S.; Tan, C.T. [Neurology Unit, Department of Medicine, University Malaya, Kuala Lumpur (Malaysia)

    2015-09-15

    Highlights: • Neuroimaging is imperative in diagnostic work up and therapeutic assessment of refractory epilepsy. • Identification of epileptogenic zone on EEG, MRI and functional imaging improves the success of surgery. • High performance MRI greatly enhanced metabolic information and elucidate brain functions. • Optimisation of epilepsy protocols in structural and functional MRI are presented in this article. - Abstract: Identification of the epileptogenic zone is of paramount importance in refractory epilepsy as the success of surgical treatment depends on complete resection of the epileptogenic zone. Imaging plays an important role in the locating and defining anatomic epileptogenic abnormalities in patients with medically refractory epilepsy. The aim of this article is to present an overview of the current MRI sequences used in epilepsy imaging with special emphasis of lesion seen in our practices. Optimisation of epilepsy imaging protocols are addressed and current trends in functional MRI sequences including MR spectroscopy, diffusion tensor imaging and fusion MR with PET and SPECT are discussed.

  4. Neuroimaging in refractory epilepsy. Current practice and evolving trends

    International Nuclear Information System (INIS)

    Ramli, N.; Rahmat, K.; Lim, K.S.; Tan, C.T.

    2015-01-01

    Highlights: • Neuroimaging is imperative in diagnostic work up and therapeutic assessment of refractory epilepsy. • Identification of epileptogenic zone on EEG, MRI and functional imaging improves the success of surgery. • High performance MRI greatly enhanced metabolic information and elucidate brain functions. • Optimisation of epilepsy protocols in structural and functional MRI are presented in this article. - Abstract: Identification of the epileptogenic zone is of paramount importance in refractory epilepsy as the success of surgical treatment depends on complete resection of the epileptogenic zone. Imaging plays an important role in the locating and defining anatomic epileptogenic abnormalities in patients with medically refractory epilepsy. The aim of this article is to present an overview of the current MRI sequences used in epilepsy imaging with special emphasis of lesion seen in our practices. Optimisation of epilepsy imaging protocols are addressed and current trends in functional MRI sequences including MR spectroscopy, diffusion tensor imaging and fusion MR with PET and SPECT are discussed

  5. Artigo revisão: atuação dos antioxidantes em refratários contendo carbono Review article: performance of the antioxidants in carbon containing refractories

    Directory of Open Access Journals (Sweden)

    A. P. Luz

    2007-12-01

    Full Text Available Os materiais refratários contendo carbono têm despertado grande atenção nos últimos anos, uma vez que são amplamente utilizados na indústria siderúrgica em virtude de suas excelentes propriedades. A presença do carbono nos refratários contribui para o aumento da resistência ao choque térmico, da energia de fratura e da resistência ao ataque por escória. Entretanto, a principal desvantagem do seu uso é a sua alta susceptibilidade a oxidação. Com o objetivo de manter o carbono presente na estrutura do material refratário o maior tempo possível, algumas medidas são requeridas para reduzir sua oxidação sob condições operacionais. Desta forma, o uso de substâncias conhecidas como antioxidantes tem sido extensivamente estudado. Os principais antioxidantes, suas características e formas de atuação são abordados nesta revisão. A formação de novos compostos devido à reação entre os antioxidantes com o carbono, nitrogênio, oxigênio e o próprio material refratário pode provocar um preenchimento parcial dos poros e redução da taxa de interdifusão dos gases, havendo assim a prevenção da oxidação do carbono presente no refratário.Carbon containing refractories have received great attention over the last years, as they are widely used in the steel making industry due to their better properties, such as: higher thermal shock resistance, fracture energy and slag resistance. However, their main disadvantage is the carbon oxidation. Aiming to keep carbon in the structure of the refractory material some actions are required in order to reduce its oxidation under operational conditions. Therefore, the use of materials known as antioxidants has been extensively studied. The main antioxidants, their characteristics and performance are discussed in the present review article. The formation of new compounds due to the reaction of the antioxidants with carbon, nitrogen, oxygen and the refractory material can induce a pore

  6. Possibility of surface carburization of refractory metals of electric spark alloying

    International Nuclear Information System (INIS)

    Verkhoturov, A.D.; Isaeva, L.P.; Timofeeva, I.I.; Tsyban', V.A.

    1981-01-01

    The paper is concerned with a study in the alloying layer formation under electric spark alloying of refractory (Ti, Zr, Nb, Mo, W, Co, Fe) metals with graphite in argon and in air using the EhFI-46A installation. It is shown that in electric spark alloying with graphite there appear certain specific conditions for the alloying layer formation manifested in the cathode mass decrease during treatment. In this case an alloying layer consisting of carbides, oxides of the corresponding metals and material of the base is formed on the metal surface. The best carburization conditions in the process of electric spark alloying are realized for group 4 metals when treating them in ''soft'' regime, specific time of alloying being 1-3 min/sm 2 and for group 5 and 6 metals - in ''rigid'' regime of treatment and specific time of alloying 3-5 min/cm 2 [ru

  7. The effect of various sintering temperature on used refractory towards its physical properties

    Science.gov (United States)

    Sudibyo; Wulandari, Y. R.; Amin, M.; Azhar

    2018-01-01

    The used magnesia refractory from the kiln of cement industry was successfully recycled to new refractory using Kaolin as an adhesive. In this work, the temperatures of sintering were varied from 1000°C to 1500°C. The result shows that the increment temperature effects in sintering process will enhance refractory physical properties such as bulk density, cold crushing strength or pressure strength and thermal conductivity. Meanwhile, the porosity was decreased as the increase of the sintering temperature.

  8. Rapid pacing results in changes in atrial but not in ventricular refractoriness

    NARCIS (Netherlands)

    Schoonderwoerd, BA; Van Gelder, IC; Tieleman, RG; Bel, KJ; Crijns, HJGM

    It is well known that atrial tachycardia causes atrial electrical remodeling, characterized by shortening of atrial effective refractory periods (AERPs) and loss of physiological adaptation of AERP to rate. However, the nature and time course of changes in ventricular effective refractory periods

  9. Transient refractory material dissolution by a volumetrically-heated melt

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, Jean Marie, E-mail: jean-marie.seiler@cea.fr [CEA, DEN, DTN, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France); Ratel, Gilles [CEA, DEN, DTN, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France); Combeau, Hervé [Institut Jean Lamour, UMR 7198, Lorraine University, Ecole des Mines de Nancy, Parc de Saurupt, 54042 Nancy Cedex (France); Gaus-Liu, Xiaoyang; Kretzschmar, Frank; Miassoedov, Alexei [Karlsruhe Institut of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2014-12-15

    Highlights: • We describe a test investigating ceramic dissolution by a molten non-eutectic melt. • The evolution of the interface temperature between melt and refractory is measured. • A theoretical model describing dissolution kinetics is proposed. • When dissolution stops, interface temperature is the liquidus temperature of the melt. - Abstract: The present work addresses the question of corium–ceramic interaction in a core catcher during a core-melt accident in a nuclear power plant. It provides an original insight into transient aspects concerning dissolution of refractory material by a volumetrically heated pool. An experiment with simulant material (LIVECERAM) is presented. Test results clearly show that dissolution of solid refractory material can occur in a non-eutectic melt at a temperature which is lower than the melting temperature of the refractory material. During the dissolution transient, the interface temperature rises above the liquidus temperature, corresponding to the instantaneous average composition of the melt pool. With constant power dissipation in the melt and external cooling of the core-catcher, a final steady-state situation is reached. Dissolution stops when the heat flux (delivered by the melt to the refractory) can be removed by conduction through the residual thickness of the ceramic, with T{sub interface} = T{sub liquidus} (calculated for the average composition of the final liquid pool). The final steady state corresponds to a uniform pool composition and uniform interface temperature distribution. Convection in the pool is governed by natural thermal convection and the heat flux distribution is therefore similar to what would be obtained for a single component pool. An interpretation of the experiment with two model-based approaches (0D and 1D) is presented. The mass transfer kinetics between the interface and the bulk is controlled by a diffusion sublayer within the boundary layer. During the dissolution transient

  10. Oxidized calmodulin kinase II regulates conduction following myocardial infarction: a computational analysis.

    Directory of Open Access Journals (Sweden)

    Matthew D Christensen

    2009-12-01

    Full Text Available Calmodulin kinase II (CaMKII mediates critical signaling pathways responsible for divergent functions in the heart including calcium cycling, hypertrophy and apoptosis. Dysfunction in the CaMKII signaling pathway occurs in heart disease and is associated with increased susceptibility to life-threatening arrhythmia. Furthermore, CaMKII inhibition prevents cardiac arrhythmia and improves heart function following myocardial infarction. Recently, a novel mechanism for oxidative CaMKII activation was discovered in the heart. Here, we provide the first report of CaMKII oxidation state in a well-validated, large-animal model of heart disease. Specifically, we observe increased levels of oxidized CaMKII in the infarct border zone (BZ. These unexpected new data identify an alternative activation pathway for CaMKII in common cardiovascular disease. To study the role of oxidation-dependent CaMKII activation in creating a pro-arrhythmia substrate following myocardial infarction, we developed a new mathematical model of CaMKII activity including both oxidative and autophosphorylation activation pathways. Computer simulations using a multicellular mathematical model of the cardiac fiber demonstrate that enhanced CaMKII activity in the infarct BZ, due primarily to increased oxidation, is associated with reduced conduction velocity, increased effective refractory period, and increased susceptibility to formation of conduction block at the BZ margin, a prerequisite for reentry. Furthermore, our model predicts that CaMKII inhibition improves conduction and reduces refractoriness in the BZ, thereby reducing vulnerability to conduction block and reentry. These results identify a novel oxidation-dependent pathway for CaMKII activation in the infarct BZ that may be an effective therapeutic target for improving conduction and reducing heterogeneity in the infarcted heart.

  11. A randomized controlled trial of the ketogenic diet in refractory childhood epilepsy

    NARCIS (Netherlands)

    Lambrechts, D.A.J.E.; de Kinderen, R.J.A.; Vles, J.S.H.; de Louw, A.J.A.; Aldenkamp, A.P.; Majoie, H.J.M.

    2017-01-01

    Objective: To evaluate the efficacy and tolerability of the ketogenic diet (KD) during the first 4 months of a randomized controlled trial (RCT) in refractory epilepsy patients aged 1–18 years. Methods: Children and adolescents with refractory epilepsy, not eligible for epilepsy surgery, were

  12. Improved cooler design of electric arc furnace refractory in mining industry using thermal analysis modeling and simulation

    International Nuclear Information System (INIS)

    Istadi, I.; Bindar, Y.

    2014-01-01

    Production of steel and nickel using the electric arc furnace should be focused on the intensification of energy. Improvement of energy efficiency of the most consuming facilities was achieved by improving the use of alternative energy minimization such as reducing the heat lost of hot gases, minimizing the heat radiated through refractory linings of metallurgical furnaces, and cooling the highly thermally stressed components. The refractory of electric arc furnace should be modified to achieve the best cooling system of the furnace. In this physical modeling and simulation works, four modification scenarios of wall refractory designs were simulated, i.e. refractory with basic design, refractory with deep plate coolers, refractory with extra plate coolers, and refractory with wall falling film coolers. Finally, the use of deep plate cooler and the existing waffle cooler system was considered to be the best design of efficient electric arc furnace operationally. - Highlights: • Electric arc furnace design should be focused on the intensification of energy. • Refractory of electric arc furnace were modified to achieve the best cooling system. • Four modification scenarios of the wall refractory designs were simulated. • Use of deep plate cooler and existing waffle cooler system is the best cooling

  13. Ixabepilone: a new chemotherapeutic option for refractory metastatic breast cancer

    Directory of Open Access Journals (Sweden)

    Shannon Puhalla

    2008-09-01

    Full Text Available Shannon Puhalla, Adam BrufskyUPMC Magee-Womens Cancer Program, University of Pittsburgh, Pittsburgh, Pennsylvania, USAAbstract: Taxane therapy is commonly used in the treatment of metastatic breast cancer. However, most patients will eventually become refractory to these agents. Ixabepilone is a newly approved chemotherapeutic agent for the treatment of metastatic breast cancer. Although it targets microtubules similarly to docetaxel and paclitaxel, ixabepilone has activity in patients that are refractory to taxanes. This review summarizes the pharmacology of ixapebilone and clinical trials with the drug both as a single agent and in combination. Data were obtained using searches of PubMed and abstracts of the annual meetings of the American Society of Clinical Oncology and the San Antonio Breast Cancer Symposium from 1995 to 2008. Ixapebilone is a semi-synthetic analog of epothilone B that acts to induce apoptosis of cancer cells via the stabilization of microtubules. Phase I clinical trials have employed various dosing schedules ranging from daily to weekly to 3-weekly. Dose-limiting toxicites included neuropathy and neutropenia. Responses were seen in a variety of tumor types. Phase II studies verified activity in taxane-refractory metastatic breast cancer. The FDA has approved ixabepilone for use as monotherapy and in combination with capecitabine for the treatment of metastatic breast cancer. Ixabepilone is an efficacious option for patients with refractory metastatic breast cancer. The safety profile is similar to that of taxanes, with neuropathy and neutropenia being dose-limiting. Studies are ongoing with the use of both iv and oral formulations and in combination with other chemotherapeutic and biologic agents.Keywords: ixabepilone, epothilone, metastatic breast cancer, taxane-refractory

  14. Cannon Wear and Erosion Science and Technology Objective Program (STO) 155-mm Projectile Rotating Band/Obturation for Extended Range

    Science.gov (United States)

    2015-06-01

    refractory metal coatings such as chrome plating have slowed the erosion at the origin but have not prevented down bore wear. Down bore wear is due...in the current projectile inventory: the M107, M864/M549A1, and the M483A1 types (fig. 1). The band material is either copper or a copper/ zinc alloy... ductility and sufficient tensile (shear) strength in order to engrave and survive 300 in. of tube travel. In the materials, these properties are

  15. Clinical outcomes of intravenous immunoglobulin therapy in refractory uveitis.

    Science.gov (United States)

    Garcia-Geremias, M; Carreño, E; Epps, S J; Lee, R W J; Dick, A D

    2015-04-01

    Intravenous immunoglobulin (IVIg) therapy has multiple mechanisms of immunomodulatory action. We wished therefore to assess its efficacy in a spectrum of patients with refractory uveitis. Retrospective review of clinical charts was conducted to document response to IVIg treatment in consecutive patients with treatment-refractory uveitis. Main outcome measures were control of intraocular inflammation, visual acuity, progression of the disease, and complications. Four (two male) patients, with a mean age at the beginning of the treatment of 47 years (range: 39-64), were included in the study. Indication for treatment was patients with active non-infectious uveitis refractory to steroids and immunomodulatory therapy. All patients received a course of 0.5 g/kg per day of IVIg for three consecutive days, repeating this course at a mean of 11 week (range: 2-39 weeks) intervals when indicated clinically. The median duration of the IVIg therapy was 7 months (range: 3-14 months). In three patients treatment resulted in stabilisation and prevention of progression of the disease, and additionally in two patients it facilitated a decrease in prednisolone dose. Treatment failed to induce long-term remission in one patient with recurrence of macular oedema. IVIg was well tolerated with neither immediate nor longer-term adverse events observed. In three out of four cases IVIg was an effective adjunctive therapy and well tolerated for the management of treatment-refractory uveitis.

  16. SULFUR REDUCTION IN GASOLINE AND DIESEL FUELS BY EXTRACTION/ADSORPTION OF REFRACTORY DIBENZOTHIOPHENES

    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Angelici

    2003-06-01

    Refractory 4,6-dimethyldibenzothiophene, which is difficult to remove from petroleum feedstocks, binds to the Ru in Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} by displacing the H{sub 2}O ligand. Thiophene, benzothiophene and dibenzothiophene (DBT) also react with Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} similarly. This binding ability of Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} has been used to remove over 50% of the DBT in simulated petroleum feedstocks by a biphasic extraction process. The extraction phase is readily regenerated by air-oxidation thereby completing a cyclic process that removes DBT from petroleum feedstocks. Solid phase extractants consisting of Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+}, CpRu(CO){sub 2}(BF{sub 4}), CpFe(CO){sub 2}(C{sub 4}H{sub 8}){sup +} and AgX (where X = BF{sub 4}{sup -}, PF{sub 6}{sup -} or NO{sub 3}{sup -}) adsorbed on silica have also been used to remove DBT and 4,6-Me{sub 2}DBT from simulated petroleum feedstocks. The AgX/silica adsorbents remove 90% of the DBT and 4,6-Me{sub 2}DBT and can be regenerated and re-used for multiple extractions, which makes these adsorbents of potential industrial use for the removal of refractory dibenzothiophenes from petroleum feedstocks.

  17. Advances in refractories for the metallurgical industries III: proceedings of the international symposium

    Energy Technology Data Exchange (ETDEWEB)

    Allaire, C.; Rigaud, M. [eds.] [Ecole Polytchnique, Montreal, PQ (Canada)

    1999-07-01

    In the three years since the last symposium key innovations have been made in the penetration of monoliths in all sectors of the metallurgical industries. The symposium was presented within the 38th Annual Conference of Metallurgists of the Canadian Institute of Mining, Metallurgy and Petroleum. Broad international coverage was maintained with papers originating from 12 different countries including: Australia, Canada, China, France, Germany, India, Iran, Japan, Korea, Mexico, New Zealand, Norway, and the United States. The 27 papers presented are divided into seven sessions to reflect the interests of the participants. The sessions included mold fluxes I and II, aluminum refractories, alumina castables, andalusite castables, continuous casting of refractories, aluminum refractories II and copper-nickel refineries. One paper on refractories for exhaust gas scrubbers is abstracted separately.

  18. Low carbon content and carbon-free refractory materials with high thermal shock resistance; Thermoschockbestaendige feuerfeste Erzeugnisse mit geringerem Kohlenstoffgehalt bzw. kohlenstofffreie Erzeugnisse

    Energy Technology Data Exchange (ETDEWEB)

    Brachhold, Nora; Aneziris, C.G.; Stein, Volker; Roungos, Vasileios; Moritz, Kirsten [TU Bergakademie Freiberg (TUBAF) (DE). Inst. fuer Keramik, Glas- und Baustofftechnik (IKGB)

    2012-07-01

    Carbon bonded refractories are essential for steelmaking due to their excellent thermal shock resistance. The research on carbon reduced and carbon-free materials is necessary to manufacture high quality stainless steels tending carbon pick-up in contact to conventional refractory materials. Further advantages are reduced emissions of CO{sub 2} and energy saving potentials due to better heat insulation properties. The challenge is to develop alternative materials with lower carbon contents but with the necessary thermal shock resistance. The Priority Programme 1418 funded by the German Research Foundation (DFG) concentrates on this problem. In this article two materials are presented. First, the carbon content could be reduced by nanoscaled additives resulting in better bonding between matrix and oxidic components. Second, an AL{sub 2}O{sub 3}-rich carbon-free material is presented showing a very good thermal shock resistance due to its designed microstructure. Finally, a steel casting simulator is introduced to test the new materials under nearly real conditions. (orig.)

  19. Étude de l’évolution de la teneur en chrome hexavalent dans le cuir, influence des conditions de fabrication et importance des facteurs environnementaux

    OpenAIRE

    Fontaine , Mathilde

    2017-01-01

    Currently, 80 to 85% of leather is tanned with chrome. This process allows to obtain excellent physico-mechanical properties with optimum economic conditions. The chromium salts in trivalent form used in the manufacturing of leather are not harmful; however under some conditions and associated with other substances, trivalent chromium can be transformed into hexavalent chromium, highly allergenic and potentially harmful to the health of the consumer. Since 1st May 2015, the presence of hexava...

  20. Determination of Cr2O3 in chrome-tanned leather by radionuclide-excited X-ray fluorescence analysis

    International Nuclear Information System (INIS)

    Melich, M.; Palagyi, S.; Kern, M.

    1989-01-01

    Preliminary results on the determination of Cr 2 O 3 in chrome-tanned leather by measuring the content of Cr by means of radionuclide-excited XRF analysis are reported. For excitation a 3.7 GBq 238 Pu source was used and the characteristic K X-rays of Cr were detected with a planar Si(Li) detector. Both smooth and rough sides of the leather were analyzed directly or with a pair of V/Ti balanced filters. A fairly good correlation was found between Cr Kx counts of the rough side and the Cr 2 O 3 concentrations determined chemically in the range of 3.5 to 6.0% Cr 2 O 3 . The method renders possible a rapid and non-destructive determination of Cr 2 O 3 in various leather samples. (author)

  1. Refractory status epilepticus and glutamic acid decarboxylase antibodies in adults: presentation, treatment and outcomes.

    Science.gov (United States)

    Khawaja, Ayaz M; Vines, Brannon L; Miller, David W; Szaflarski, Jerzy P; Amara, Amy W

    2016-03-01

    Glutamic acid decarboxylase antibodies (GAD-Abs) have been implicated in refractory epilepsy. The association with refractory status epilepticus in adults has been rarely described. We discuss our experience in managing three adult patients who presented with refractory status epilepticus associated with GAD-Abs. Case series with retrospective chart and literature review. Three patients without pre-existing epilepsy who presented to our institution with generalized seizures between 2013 and 2014 were identified. Seizures proved refractory to first and second-line therapies and persisted beyond 24 hours. Patient 1 was a 22-year-old female who had elevated serum GAD-Ab titres at 0.49 mmol/l (normal: status epilepticus. Causation cannot be established since GAD-Abs may be elevated secondary to concurrent autoimmune diseases or formed de novo in response to GAD antigen exposure by neuronal injury. Based on this report and available literature, there may be a role for immuno- and chemotherapy in the management of refractory status epilepticus associated with GAD-Abs.

  2. Evaluation of olivine refractories for TES

    Science.gov (United States)

    Gay, B. M.; Cochrane, R. L.; Palmour, H., III; Paisley, M. J.

    1982-02-01

    The principal objectives of this program are to (1) experimentally determine the degree of improvement in thermal and mechanical performance that can be obtained with an olivine thermal storage brick made of domestic materials using advanced processing techniques compared with state-of-the-art as represented by commercial European bricks, (2) conduct an assessment of existing German ceramic process technology and determine its adaptability to domestic raw materials and manufacturing practices, and (3) investigate, on a limited basis, method for further improvement of domestic-olivine brick. To date, accomplishments include (1) installation of improved, computer-based instrumentation, (2) the use of this system to determine performance characteristics of a set of heat storage refractories under cyclic use conditions, (3) acquisition of the services of a knowledgeable European consultant, (4) continued lab-scale process/property optimization studies, and (5) comparative testing of olivine-based and magnesite-based heat storage refractories in the calorimetric test facility at Purdue University.

  3. An unusual case of refractory wheeze

    Science.gov (United States)

    Ramesh, Venkat; Acharya, Vishak; Pai, Narasimha; Krishnan, Ananda

    2015-01-01

    A 37-year-old man presented with a history of episodic wheeze and breathlessness of 3 years’ duration refractory to treatment. Physical examination revealed diffuse expiratory polyphonic rhonchi while the remainder of the examination including the cardiac examination was reported as normal. Pulmonary function testing revealed mild obstruction with bronchodilator reversibility. The patient was discharged on a 6-month course of antitubercular treatment (ATT) as bronchial brush cytology (obtained via bronchoscopy) was positive for acid-fast bacilli. The patient presented after completing 6 months of ATT with persistent symptoms, a loud S1 and a mid-diastolic murmur at the apex. High-resolution CT of the chest showed bilateral dependent ground glass opacities. An echocardiogram revealed a left atrial myxoma, and normal RV size and pressures. The patient underwent successful surgical removal of the same, and made a complete recovery. Refractory wheeze is a very unusual presentation of a left atrial myxoma. PMID:25733086

  4. Preparation and characterization of clay bonded high strength silica refractory by utilizing agriculture waste

    International Nuclear Information System (INIS)

    Bhardwaj, A.; Hossain, S.K.S.; Majh, M.R.

    2017-01-01

    Clay bonded silica refractory was prepared by utilizing agriculture waste called rice husk ash (RHA) and refractory grog. Various samples were prepared with different compositions based upon partial replacement of quartz by RHA. Rectangular samples were prepared by following semi dry process prior to pressing in a uniaxial hydraulic press and sintering at a temperature of 1200°C in air atmosphere. Various physical, mechanical and thermal characterizations were done like X-ray diffraction (XRD), scanning electron microscope (SEM), apparent porosity (AP), bulk density (BD), cold crushing strength (CCS), refractoriness and thermal conductivity measurement. The sample utilizing 30% of RHA was considered most optimum composition which produced cold crushing strength of 38MPa and thermal conductivity of 2.08W/mK at 800°C with a considerable good refractoriness. Enhancement in the mechanical as well as thermal properties may be considered as attributed to the amorphous silica which has reacted more easily and efficiently with other material surrounding giving rise to the densification and produced stable crystalline phase to the refractory material. These promising characteristics suggests that the RHA may lead to be used as a potential material for the preparation of clay bonded high strength silica refractories. [es

  5. Refractory heartburn: comparison of intercellular space diameter in documented GERD vs. functional heartburn.

    Science.gov (United States)

    Vela, Marcelo F; Craft, Brandon M; Sharma, Neeraj; Freeman, Janice; Hazen-Martin, Debra

    2011-05-01

    Refractory heartburn despite acid suppression may be explained by ongoing gastroesophageal reflux disease (GERD) or functional heartburn (FH), i.e., symptoms without evidence of GERD. Impedance-pH monitoring (impedance-pH) detects acid and nonacid reflux and is useful for evaluating acid-suppressed, refractory patients. Intercellular space diameter (ISD) of esophageal epithelium measured by transmission electron microscopy (TEM) is a marker of epithelial damage present in both erosive and nonerosive reflux disease. ISD has not been used to study refractory heartburn or FH. Our aim was to compare ISD in healthy controls and refractory heartburn patients with GERD and FH. In refractory heartburn patients (heartburn more than twice/week for at least 2 months despite proton pump inhibitor (PPI) b.i.d.), erosive esophagitis and/or abnormal impedance-pH (increased acid exposure or positive symptom index) defined GERD; normal esophagogastroduodenoscopy (EGD)/impedance-pH defined FH. Asymptomatic, healthy controls had normal EGD and pH-metry. Mean ISD in each subject, determined by blinded TEM of esophageal biopsies, was the average of 100 measurements (10 measurements in each of 10 micrographs). In all, 11 healthy controls, 11 FH, and 15 GERD patients were studied. Mean ISD was significantly higher in GERD compared with controls (0.87 vs. 0.32 μm, P=0.003) and FH (0.87 vs. 0.42 μm, P=0.012). Mean ISD was similar in FH and controls (0.42 vs. 0.32 μm, P=0.1). The proportion of patients with abnormal ISD was significantly higher for GERD compared with FH (60 vs. 9%, P=0.014). ISD is increased in refractory heartburn patients with GERD but not those with FH. Our findings suggest that measurement of ISD by TEM might be a useful tool to distinguish GERD from FH in patients with refractory heartburn.

  6. Oxidative DNA damage in bone marrow cells of patients with low-risk myelodysplastic syndrome

    Czech Academy of Sciences Publication Activity Database

    Novotná, Božena; Bagryantseva, Yana; Šišková, M.; Neuwirtová, R.

    2009-01-01

    Roč. 33, č. 2 (2009), s. 340-343 ISSN 0145-2126 R&D Projects: GA MZd NR8265 Institutional research plan: CEZ:AV0Z50390512 Keywords : Myelodysplastic syndrome * Refractory anemia * Oxidative DNA damage Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.358, year: 2009

  7. Colectomy for refractory constipation

    DEFF Research Database (Denmark)

    Raahave, Dennis; Loud, Franck Bjørn; Christensen, Elsebeth

    2010-01-01

    OBJECTIVE: This study evaluated the type of colectomy, postoperative complications, functional results, and satisfaction in patients with constipation refractory to conservative therapy. Further, colonic transit time (CTT), faecal load (coprostasis), and colon length (redundancies) were compared...... had at hemicolectomy, 11 patients a subtotal colectomy and 3 patients an ileostomy. Two patients had an anastomotic leak and one died. In 11 patients, further surgery was necessary, because of recurrent constipation. Abdominal pain disappeared and defecation patterns improved significantly to 1-4 per...

  8. Refractory alloy component fabrication

    International Nuclear Information System (INIS)

    Young, W.R.

    1984-01-01

    Purpose of this report is to describe joining procedures, primarily welding techniques, which were developed to construct reliable refractory alloy components and systems for advanced space power systems. Two systems, the Nb-1Zr Brayton Cycle Heat Receiver and the T-111 Alloy Potassium Boiler Development Program, are used to illustrate typical systems and components. Particular emphasis is given to specific problems which were eliminated during the development efforts. Finally, some thoughts on application of more recent joining technology are presented. 78 figures

  9. Supersonic pulsed free-jet of atoms and molecules of refractory metals: laser induced fluorescence spectroscopic studies on zirconium atoms and zirconium oxide molecules

    International Nuclear Information System (INIS)

    Nakhale, S.G.

    2004-11-01

    The experimental setup for generating supersonic pulsed free-jet containing atoms and molecules of refractory nature has been built. The technique of laser vaporization in conjunction with supersonic cooling is used to generate these species. The cooled atoms and molecules in supersonic free-jet are probed by laser induced fluorescence spectroscopy. In particular, the technique has been used to perform low-resolution laser induced fluorescence spectroscopy, limited by laser linewidth, on cold Zr atoms and ZrO molecules. The translational temperatures of ∼ 26.5 K and the rotational temperatures of ∼ 81 K have been achieved. It is possible to achieve the Doppler width of few tens of MHz allowing it to perform high-resolution spectroscopy on these atomic and molecular species. Also because of low rotational temperature of molecules the spectral congestion is greatly reduced. In general, this technique can be applied to perform spectroscopy on atoms and molecules of refractory nature. (author)

  10. Method for hot pressing irregularly shaped refractory articles

    Science.gov (United States)

    Steinkamp, William E.; Ballard, Ambrose H.

    1982-01-01

    The present invention is directed to a method for hot pressing irregularly haped refractory articles with these articles of varying thickness being provided with high uniform density and dimensional accuracy. Two partially pressed compacts of the refractory material are placed in a die cavity between displaceable die punches having compact-contacting surfaces of the desired article configuration. A floating, rotatable block is disposed between the compacts. The displacement of the die punches towards one another causes the block to rotate about an axis normal to the direction of movement of the die punches to uniformly distribute the pressure loading upon the compacts for maintaining substantially equal volume displacement of the powder material during the hot pressing operation.

  11. Ketogenic Diet in Super-Refractory Status Epilepticus

    OpenAIRE

    Smith, Garnett; Press, Craig A.

    2017-01-01

    Researchers from the Children’s National Health System in Washington, D.C. studied the feasibility, rate of complications, and effect on seizures of initiating the Ketogenic Diet (KD) in pediatric patients with Super-Refractory Status Epilepticus (SRSE).

  12. Development of spectrophotometric determination of beryllium in beryl minerals using chrome Azurol S

    Directory of Open Access Journals (Sweden)

    Hisham K. Fouad

    2016-09-01

    Full Text Available A developed, direct, rapid, and sensitive spectrophotometric determination of beryllium in beryl minerals with Chrome Azurol S (CAS as a chromogenic reagent was developed in the present article. The determination was performed without either solvent extraction or ion exchange separation of beryllium from its matrix. The stable 1:1 Be-CAS complex was formed instantly with duration time of at least 24 h with constant absorbance. Different parameters such as wavelengths, pH, EDTA concentration and dye concentration were studied for the optimum determination of beryllium. Interference due to presence of high aluminum concentrations was overcome by adding 5% EDTA disodium salt solution. Maximum absorbance for Be-CAS complex was performed at λmax 568 NM using acetate buffer at pH 4.6. Beer’s law was obeyed in the range from 0.02 to 9 ppm with molar absorptivity ε = 0.22 × 104 mol−1 cm−1 and an average standard deviation of 0.7. The R.S.D for 10 replicate measurements of 1 ppm Be was 1.2%.

  13. Clinical and etiological profile of refractory rickets from western India.

    Science.gov (United States)

    Joshi, Rajesh R; Patil, Shailesh; Rao, Sudha

    2013-07-01

    To present clinical and etiological profile of refractory rickets from Mumbai. Case records of 36 patients presenting over 2½ y with refractory rickets were evaluated with respect to clinical presentation, biochemical, radiological features and where needed, ophthalmological examination, ultrasonography and special tests on blood and urine. Twenty three (63 %) patients had renal tubular acidosis (RTA)-distal RTA in 20 and proximal RTA in 3 patients; 5 (14 %) had vitamin D dependent rickets (VDDR I in 2 and VDDR II in 3 patients), 4 (11 %) had chronic renal failure (CRF) and 2 each (6 %) had hypophosphatemic rickets and chronic liver disease as cause of refractory rickets. A significant proportion of patients with RTA and VDDR showed skeletal changes of rickets in the first 2 y of life, while those with hypophosphatemic rickets presented later. Patients with hypophosphatemic rickets had predominant involvement of lower limbs, normal blood calcium and PTH levels and phosphorus leak in urine. All patients with RTA presented with failure to thrive, polyuria and marked rickets; blood alkaline phosphatase levels being normal in almost 50 % patients. Three (75 %) patients with rickets due to CRF had GFR rickets inspite of taking high dose of vitamin D orally. Refractory rickets is a disorder of multiple etiologies; a good history and clinical examination supplemented with appropriate investigations helps to determine its cause.

  14. USE OF STRUCTURAL MRI IN PATIENTS WITH MEDICALLY REFRACTORY SEIZURES

    Directory of Open Access Journals (Sweden)

    Ara G. Kaprelyan

    2012-12-01

    Full Text Available Introduction: Refractory epilepsy is common in patients with structural brain lesions including acquired disorders and genetic abnormalities. Recently, MRI is a precise diagnostic tool for recognition of different structural causes underlying medically intractable seizures.Objective: To evaluate the usefulness of MRI for detection of brain lesions associated with refractory epilepsy.Material and methods: 49 patients (20M and 29F; aged 48.6±24.7 years with refractory epilepsy were included in the study. They presented with partial (46.0%, secondary (31.0% or primary (23.0% generalized tonic-clonic seizures. Clinical diagnosis was based on the revised criteria of ILAE. Structural neuroimaging (MRI, EEG recording, and neurological examination were performed.Results: MRI detected different structural brain abnormalities totally in 36 (73.5% patients, including cerebral tumors (21p, cerebrovascular accidents (5p, hyppocampal sclerosis (3p, developmental malformations (2p, postencephalitic lesions (2p, arachnoid cysts (2p, and tuberous sclerosis (1p. Neuroimaging revealed normal findings in 13 (27.5% cases. EEG recordings showed focal epileptic activity in 38 (77.6% patients, including 33 cases with and 5 without structural brain abnormalities.Conclusion: This study revealed that structural brain lesions are commonly associated with refractory epilepsy. We suggested that MRI is a useful diagnostic method for assessment of patients with uncontrolled seizures or altered epileptic pattern.

  15. Penetration and Effectiveness of Micronized Copper in Refractory Wood Species.

    Science.gov (United States)

    Civardi, Chiara; Van den Bulcke, Jan; Schubert, Mark; Michel, Elisabeth; Butron, Maria Isabel; Boone, Matthieu N; Dierick, Manuel; Van Acker, Joris; Wick, Peter; Schwarze, Francis W M R

    2016-01-01

    The North American wood decking market mostly relies on easily treatable Southern yellow pine (SYP), which is being impregnated with micronized copper (MC) wood preservatives since 2006. These formulations are composed of copper (Cu) carbonate particles (CuCO3·Cu(OH)2), with sizes ranging from 1 nm to 250 μm, according to manufacturers. MC-treated SYP wood is protected against decay by solubilized Cu2+ ions and unreacted CuCO3·Cu(OH)2 particles that successively release Cu2+ ions (reservoir effect). The wood species used for the European wood decking market differ from the North American SYP. One of the most common species is Norway spruce wood, which is poorly treatable i.e. refractory due to the anatomical properties, like pore size and structure, and chemical composition, like pit membrane components or presence of wood extractives. Therefore, MC formulations may not suitable for refractory wood species common in the European market, despite their good performance in SYP. We evaluated the penetration effectiveness of MC azole (MCA) in easily treatable Scots pine and in refractory Norway spruce wood. We assessed the effectiveness against the Cu-tolerant wood-destroying fungus Rhodonia placenta. Our findings show that MCA cannot easily penetrate refractory wood species and could not confirm the presence of a reservoir effect.

  16. Wettability between TiN,TiC Containing Carbon Composite Refractory and Molten Slag or Hot Metal

    Institute of Scientific and Technical Information of China (English)

    SHIYue-xun; LIYingand; 等

    1994-01-01

    In order to develop a new-type TiC-TiN containing carbon composite refractory so as to improve the service life of blast furnace hearth,the wettability between the carbon refractory and molten slag or metal has been mea-sured.It was indicated that the carbon refractory is wet-ted by slag(θ≤90°) when(TiC+TiN)>33.52%,The effects of TiN or TiC on wetting behavior are basi-cally identical.When the amount of TiC in the carbon com-posite refractory is greater than 60% it will be wetted by hot metal;therefore,the carbon composite refractory will be wetted by slag but not permeated by hot metal when the amount of TiC is restricted.

  17. Refractory Coated/Lined Low Density Structures, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This project addresses the development of refractory coated or lined low density structures applicable for advanced future propulsion system technologies. The...

  18. Applications of electricity and corrosion. Precautions for use of metals and stainless and refractory alloys

    International Nuclear Information System (INIS)

    Gras, J.M.

    1993-09-01

    The development of applications of electricity poses highly diversified problems with materials where the resistance to corrosion prevails. Corrosion occurs under various conditions, which sometimes look harmless, and it covers diverse phenomenons linked to the nature of materials and to the physical and chemical context. However, in spite of the diversity of the processes used (electrical boilers, mechanical steam compression, heat pumps, Joule effect,) the knowledge required to approach the corrosion problems corresponds to a limited number of generic situations with regard not only to the phenomenons proper (general corrosion of copper, pitting and stress corrosion cracking of stainless steels, refractory alloys oxidation,) but also to chemical conditions which favour the corrosion (natural waters, acidic condensates, hot gases). This report is a short guide to anti-corrosion. With the aid of questions asked during the past few years, it aims to provide engineers in charge of the development of applications of electricity with a few recommendations upon the precautions for use of metallic materials. We analyze in turn the problems met with wet air and drying mists, chloride-containing neutral waters, alkaline waters and caustic media, acidic waters and concentrated acids, and, last, hot gases. We lay stress upon the behaviour of materials deemed to withstand corrosion under aqueous conditions (stainless steels and alloys, copper,titanium) and corrosion at high temperatures (refractory alloys). (author). 11 figs., 43 refs., 11 tabs

  19. Refractory Hypertension: Determination of Prevalence, Risk Factors and Comorbidities in a Large, Population-Based Cohort

    Science.gov (United States)

    Calhoun, David A.; Booth, John N.; Oparil, Suzanne; Irvin, Marguerite R.; Shimbo, Daichi; Lackland, Daniel T.; Howard, George; Safford, Monika M.; Muntner, Paul

    2014-01-01

    Refractory hypertension is an extreme phenotype of antihypertensive treatment failure. Participants in the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study, a large (n=30,239), population-based cohort were evaluated to determine the prevalence of refractory hypertension and associated cardiovascular risk factors and comorbidities. Refractory hypertension was defined as uncontrolled blood pressure (systolic/diastolic ≥ 140/90 mm Hg) on ≥ 5 antihypertensive drug classes. Participants with resistant hypertension (systolic/diastolic ≥140/90 mm Hg on ≥ 3 orhypertensive participants served as comparator groups. Of 14,809 REGARDS participants receiving antihypertensive treatment, 78 (0.5%) had refractory hypertension. The prevalence of refractory hypertension was 3.6% among participants with resistant hypertension(n=2,144) and 41.7% among participants on 5 or more antihypertensive drug classes. Among all hypertensive participants, African American race, male gender, living in the stroke belt or buckle, higher body mass index, lower heart rate, reduced estimated glomerular filtration rate, albuminuria, diabetes and history of stroke and coronary heart disease were associated with refractory hypertension. Compared to resistant hypertension, prevalence ratios for refractory hypertension were increased for African Americans (3.00, 95% CI 1.68 – 5.37) and those with albuminuria (2.22, 95% CI 1.40 – 3.52) and diabetes (2.09, 95% CI 1.32 – 3.31). The median 10-year Framingham risk for coronary heart disease and stroke was higher among participants with refractory hypertension compared to either comparator group. These data indicate that while resistant hypertension is relatively common among treated hypertensive patients, true antihypertensive treatment failure is rare. PMID:24324035

  20. Super-refractory status epilepticus in West China.

    Science.gov (United States)

    Tian, L; Li, Y; Xue, X; Wu, M; Liu, F; Hao, X; Zhou, D

    2015-07-01

    This study aims to determine the general frequency, mortality, and risk factors of super-refractory status epilepticus (SRSE) versus non-refractory status epilepticus (NRSE) and refractory status epilepticus (RSE). This work is a retrospective study. Clinical data of patients who were diagnosed with status epilepticus (SE) in the neurological ward and neuro-intensive care unit of West China Hospital from January 2009 to December 2012 were collected and analyzed. A total of 98 patients were included in the study. The percentages of NRSE, RSE, and SRSE were 67.3%, 20.4%, and 12.2%, respectively. Convulsive SE was the main seizure type among the three groups. The most common cause of NRSE was related to epilepsy (EP). However, 67.7% of SRSE cases were caused by acute encephalitis. Moreover, 47% of SE and 40% of RSE cases had a history of EP, whereas only 8.3% of SRSE cases had such history (P  0.05). The general mortality of SE was 7.1%, whereas that of SRSE was 50%. During follow-up, most SRSE patients who survived have developed symptomatic EP. This study was the first to use the statistical percentage of SRSE. Approximately 12.2% of SE cases will result in SRSE, which is a challenging medical situation for doctors. Patients with first episodes and acute encephalitis were also prone to develop SRSE. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Refractory experience in circulating fluidized bed combustors, Task 7

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, R.Q.

    1989-11-01

    This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE's Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.

  2. Refractory metal component technology for in-core sensor design

    International Nuclear Information System (INIS)

    Cannon, C.P.

    1986-02-01

    Within recent years, an increasing concern over reactor safety has prompted tests that characterize reactor core environments during transient conditions. Such tests include the Loss-of-Fluid-Tests (Idaho National Engineering Lab (INEL)), Severe Fuel Damage Tests (INEL), Core Debris Rubble Tests (Sandia National Laboratories (SNL)), and similar tests performed by foreign nations. The in-core sensors for these tests require refractory metal components to be compatible with electrical insulator materials as well as materials comprising highly corrosive service mediums. This paper presents the refractory metal technology utilized to provide basic sensor designs in the above mentioned reactor tests

  3. Mechanical activation of ceramic powders and its influence on the quality of the refractory linings

    International Nuclear Information System (INIS)

    Ceganac, Z.; Acimovic, Z.; Andric, Lj.; Petrov, M.; Mihajlovic, S.

    2003-01-01

    In the paper we present results of the investigation of the influence of mechanical activation of ceramic powders-talc and alumina, on the quality of refractory linings for casting applications. It is shown that additional fine grinding of ceramic powders increases the quality of the refractory lining. Grinding and activation of the particles with various granulations contributes to the creation of the homogenous continuous layer of refractory lining on the sand moulds and cores, as well as on the evaporating polystyrene patterns for applications in the Lost foam casting process. Refractory linings obtained within the activation of particles procedure have better adherence to moulds, cores and evaporating patterns. (Original)

  4. High Throughput Drug Sensitivity Assay and Genomics- Guided Treatment of Patients With Relapsed or Refractory Acute Leukemia

    Science.gov (United States)

    2018-02-28

    Acute Leukemia of Ambiguous Lineage; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Refractory Acute Myeloid Leukemia; Refractory Adult Acute Lymphoblastic Leukemia; Refractory Childhood Acute Lymphoblastic Leukemia

  5. Testing Consent Order on Refractory Ceramic Fibers

    Science.gov (United States)

    This notice announces that EPA has signed signed an enforceable testing consent order under the Toxic Substances Control Act (TSCA), 15 U.S.C. section 2601 at seq., with three of the primary producers of refractory ceramic fibers (RCF).

  6. Improving outcomes of refractory celiac disease – current and emerging treatment strategies

    Directory of Open Access Journals (Sweden)

    Woodward J

    2016-08-01

    Full Text Available Jeremy Woodward Department of Gastroenterology and Clinical Nutrition, Addenbrooke’s Hospital, Cambridge, UK Abstract: Intestinal inflammation and symptoms of celiac disease (CD usually respond well to gluten withdrawal, but rare cases are refractory to diet. Two types of refractory CD are discriminated on the basis of the presence or absence of an atypical population of mucosal lymphocytes that may progress to enteropathy-associated T-cell lymphoma. Challenges remain in the secure diagnosis of both types of refractory disease, and evidence on which to base treatment recommendations is flawed by the small numbers of reported patients and the use of different diagnostic strategies. Recent advances in our understanding of the mechanisms of the condition in conjunction with the development of immunomodulatory agents for managing other inflammatory diseases are helping to shape future approaches to targeted therapy. Progression will depend on collaboration and recruitment to trials. In the meantime, there is evidence to suggest that earlier diagnosis and better follow-up and management of CD may prevent the development of refractoriness. Keywords: celiac disease, gluten, small intestine, lymphoma, lymphocytes

  7. NOVEL REFRACTORY MATERIALS FOR HIGH ALKALI, HIGH TEMPERATURE ENVIRONMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, James Gordon [ORNL; Smith, Jeffrey D [ORNL; O' Hara, Kelley [University of Missouri, Rolla; Rodrigues-Schroer, Angela [Minteq International, Inc.; Colavito, [Minteq International, Inc.

    2012-08-01

    A project was led by Oak Ridge National Laboratory (ORNL) in collaboration with a research team comprised of the academic institution Missouri University of Science and Technology (MS&T), and the industrial company MINTEQ International, Inc. (MINTEQ), along with representatives from the aluminum, chemical, glass, and forest products industries. The project was to address the need for new innovative refractory compositions by developing a family of novel MgO-Al 2O3, MgAl2O4, or other similar spinel structured or alumina-based unshaped refractory compositions (castables, gunnables, shotcretes, etc.) utilizing new aggregate materials, bond systems, protective coatings, and phase formation techniques (in-situ phase formation, altered conversion temperatures, accelerated reactions, etc). This family of refractory compositions would then be tailored for use in high-temperature, high-alkaline industrial environments like those found in the aluminum, chemical, forest products, glass, and steel industries. Both practical refractory development experience and computer modeling techniques were used to aid in the design of this new family of materials. The newly developed materials were expected to offer alternative material choices for high-temperature, high-alkali environments that were capable of operating at higher temperatures (goal of increasing operating temperature by 100-200oC depending on process) or for longer periods of time (goal of twice the life span of current materials or next process determined service increment). This would lead to less process down time, greater energy efficiency for associated manufacturing processes (more heat kept in process), and materials that could be installed/repaired in a more efficient manner. The overall project goal was a 5% improvement in energy efficiency (brought about through a 20% improvement in thermal efficiency) resulting in a savings of 3.7 TBtu/yr (7.2 billion ft3 natural gas) by the year 2030. Additionally, new

  8. Service life prediction for refractory materials

    Czech Academy of Sciences Publication Activity Database

    Boccaccini, D. N.; Cannio, M.; Volkov-Husović, T. D.; Kamseu, E.; Romagnoli, M.; Veronesi, P.; Leonelli, C.; Dlouhý, Ivo; Boccaccini, A. R.

    2008-01-01

    Roč. 43, č. 12 (2008), s. 4079-4090 ISSN 0022-2461 R&D Projects: GA ČR(CZ) GA106/05/0495 Institutional research plan: CEZ:AV0Z20410507 Keywords : refractory materials * ultrasonic velocity * fracture toughness Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 1.181, year: 2008

  9. Refractory chronic cluster headache

    DEFF Research Database (Denmark)

    Mitsikostas, Dimos D; Edvinsson, Lars; Jensen, Rigmor H

    2014-01-01

    Chronic cluster headache (CCH) often resists to prophylactic pharmaceutical treatments resulting in patients' life damage. In this rare but pragmatic situation escalation to invasive management is needed but framing criteria are lacking. We aimed to reach a consensus for refractory CCH definition...... for clinical and research use. The preparation of the final consensus followed three stages. Internal between authors, a larger between all European Headache Federation members and finally an international one among all investigators that have published clinical studies on cluster headache the last five years...

  10. Chrome Tanning Leather of Giant Sea Perch Combined with Seed Extract Areca Nut on the Physical Characteristics

    Directory of Open Access Journals (Sweden)

    Bustami - Ibrahim

    2014-11-01

    Full Text Available Tanning is the process of converting raw hide protein to leather, which are stable, not easily decompose, and is suitable for a variety of uses. The use of vegetable based tanning materials in the leather tanning process has not been carried out. Vegetable based materials that were used are betel nuts. This plant contains tannin which is the main agent in the process of leather tanning. The aim of this study was to determine the physical characteristics of snapper leather treated with betel nut extract. Soxhlet extracting method with methanol as a solvent were used to obtain tannin from betel nuts. Tanned Snapper Leather were analyzed for physical quality, elongation strength, tensile strength, tear strength, and sewing strength. The result showed that methanol extracted betel nut with 10% concentration gives the optimum physical characteristics.Keywords: areca nut, chrome, snapper, snapper

  11. Chromed Leather Dyeing Peculiarities when Deliming with Peracetic Acid

    Directory of Open Access Journals (Sweden)

    Kęstutis BELEŠKA

    2013-05-01

    Full Text Available The research was aimed to investigate the influence of deliming with peracetic acid on leather dyeing kinetics. Hydrophobic C.I. Acid Red 213 and hydrophilic C.I. Acid Red 423 dyes were used. Sorption of dye depends on hydrophobicity/hydrophility of dye and dyeing temperature. Equilibrium of process is reached faster using hydrophobic C.I. Acid Red 213 at 45 ºC. However, both control and experimental leather fibres adsorb more hydrophilic dye C.I. Acid Red 423 and this fact does not depend on temperature. The diffusion coefficient of dye C.I. Acid Red 423 calculated according to Weisz model is higher when dyeing conventional leather. The change of deliming method has influence on chromed leather dyeing but this influence is not significant. The adsorption ability of control leather fibres at 30 ºC and 45 ºC is higher using both dyes as compared to the dyeing the experimental one. The increase of dyeing temperature increases the adsorption ability independently on the sort of leather fibres. Such dependence of the adsorption ability on the temperature shows that hydrophobic action and van der Waals forces prevail between dye and fibres during dyeing process. The Gibbs energy changes show that adsorption of both dyes by leather fibres independently on their sort is a spontaneous process. The affinity of both dyes to conventional leather fibres is higher comparing with experimental one. The change of enthalpy is positive in all cases, and it means that the driving force of the dyeing is the change of entropy.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4431

  12. Refractory Depression, Fatigue, Irritable Bowel Syndrome, and Chronic Pain: A Functional Medicine Case Report.

    Science.gov (United States)

    Plotnikoff, Gregory; Barber, Melissa

    2016-01-01

    Single-disorder or single-organ-system clinical practice guidelines are often of limited usefulness in guiding effective management of patients with chronic multidimensional signs and symptoms. The presence of multiple long-standing medical problems in a given patient despite intensive medical effort suggests that addressing systemic core imbalances could complement more narrowly focused approaches. A 72-year-old man experiencing longstanding depression, fatigue, irritable bowel syndrome, and chronic pain in the context of additional refractory illnesses was assessed and treated, guided by a system-oriented approach to underlying core imbalances termed functional medicine. This patient was referred from a team of clinicians representing primary care, cardiology, gastroenterology, hematology, and psychology. Prior treatment had been unsuccessful in managing multiple chronic comorbidities. Diagnostic assessment included comprehensive stool and nutritional/metabolic laboratory testing. The blood-, urine-, or stool-based measurements of relevant markers for multiple systemic issues, including digestion/absorption, inflammation, oxidative stress, and methylation, identified previously unrecognized root causes of his constellation of symptoms. These functional measurements guided rational recommendations for dietary choices and supplementation. The patient experienced steady and significant improvement in his mental health, fatigue, chronic pain, and irritable bowel syndrome-as well as the unexpected resolution of his chronic idiopathic pancytopenia. The success in this case suggests that other patients with chronic, complex, and treatment-refractory illness may benefit from a system-oriented assessment of core imbalances guided by specialized nutritional/metabolic and digestive laboratory testing.

  13. Iron Refractory Iron Deficiency Anaemia: A Rare Cause of Iron Deficiency Anaemia

    LENUS (Irish Health Repository)

    McGrath, T

    2018-01-01

    We describe the case of a 17-month-old boy with a hypochromic microcytic anaemia, refractory to oral iron treatment. After exclusion of dietary and gastrointestinal causes of iron deficiency, a genetic cause for iron deficiency was confirmed by finding two mutations in the TMPRSS6 gene, consistent with a diagnosis of iron-refractory iron deficiency anaemia (IRIDA).

  14. Long-time rupture strength and creep behaviour of welded joints on heat-resistant CrMoV steels with 1 and 12% chrome

    International Nuclear Information System (INIS)

    Maier, G.; Maile, K.; Theofel, H.

    1985-01-01

    Power plant components in the creep range are damaged frequently in the weld joint zones. The investigation concentrated therefore on the reliability of the information supplied by tests on small- and large-size samples. Creep rupture tests of dissimilar welded joints (1% with 12% chrome) with variations of heat input and weld metal have been conducted. At creep rupture times of about 10 4 h all joints failed in the outside heat affected zone of the weaker base metal. Large-size samples, proved in comparison at same stresses, showed distinctly longer times to rupture. (orig.) [de

  15. Mixed Uranium/Refractory Metal Carbide Fuels for High Performance Nuclear Reactors

    International Nuclear Information System (INIS)

    Knight, Travis; Anghaie, Samim

    2002-01-01

    Single phase, solid-solution mixed uranium/refractory metal carbides have been proposed as an advanced nuclear fuel for advanced, high-performance reactors. Earlier studies of mixed carbides focused on uranium and either thorium or plutonium as a fuel for fast breeder reactors enabling shorter doubling owing to the greater fissile atom density. However, the mixed uranium/refractory carbides such as (U, Zr, Nb)C have a lower uranium densities but hold significant promise because of their ultra-high melting points (typically greater than 3700 K), improved material compatibility, and high thermal conductivity approaching that of the metal. Various compositions of (U, Zr, Nb)C were processed with 5% and 10% metal mole fraction of uranium. Stoichiometric samples were processed from the constituent carbide powders, while hypo-stoichiometric samples with carbon-to-metal (C/M) ratios of 0.92 were processed from uranium hydride, graphite, and constituent refractory carbide powders. Processing techniques of cold uniaxial pressing, dynamic magnetic compaction, sintering, and hot pressing were investigated to optimize the processing parameters necessary to produce high density (low porosity), single phase, solid-solution mixed carbide nuclear fuels for testing. This investigation was undertaken to evaluate and characterize the performance of these mixed uranium/refractory metal carbides for high performance, ultra-safe nuclear reactor applications. (authors)

  16. Development of silicide coating over molybdenum based refractory alloy and its characterization

    International Nuclear Information System (INIS)

    Chakraborty, S.P.; Banerjee, S.; Sharma, I.G.; Suri, A.K.

    2010-01-01

    Molybdenum based refractory alloys are potential candidate materials for structural applications in high temperature compact nuclear reactors and fusion reactors. However, these alloys being highly susceptible to oxidation in air or oxygen at elevated temperature, undergoes severe losses from highly volatile molybdenum trioxide species. Present investigation, therefore, examines the feasibility of development of silicide type of coating over molybdenum base TZM alloy shape (Mo > 99 wt.%) using pack cementation coating technique. TZM alloy was synthesized in this laboratory from oxide intermediates of MoO 2 , TiO 2 and ZrO 2 in presence of requisite amount of carbon, by alumino-thermic reduction smelting technique. The arc melted and homogenized samples of TZM alloy substrate was then embedded in the chosen and intimately mixed pack composition consisting of inert matrix (Al 2 O 3 ), coating powder (Si) and activator (NH 4 Cl) taken in the judicious proportion. The sealed charge packs contained in an alumina crucible were heated at temperatures of 1000 o C for 8-16 h heating cycle to develop the coating. The coating phase was confirmed to be of made of MoSi 2 by XRD analysis. The morphology of the coating was studied by SEM characterization. It had revealed that the coating was diffusion bonded where Si from coating diffused inward and Mo from TZM substrate diffused outward to form the coating. The coating was found to be resistant to oxidation when tested in air up to 1200 o C. A maximum 100 μm of coating thickness was achieved on each side of the substrate.

  17. Approaches to refractory epilepsy

    Directory of Open Access Journals (Sweden)

    Jerome Engel

    2014-01-01

    Full Text Available Epilepsy is one of the most common serious neurological conditions, and 30 to 40% of people with epilepsy have seizures that are not controlled by medication. Patients are considered to have refractory epilepsy if disabling seizures continue despite appropriate trials of two antiseizure drugs, either alone or in combination. At this point, patients should be referred to multidisciplinary epilepsy centers that perform specialized diagnostic testing to first determine whether they are, in fact, pharmacoresistant, and then, if so, offer alternative treatments. Apparent pharmacoresistance can result from a variety of situations, including noncompliance, seizures that are not epileptic, misdiagnosis of the seizure type or epilepsy syndrome, inappropriate use of medication, and lifestyle issues. For patients who are pharmacoresistant, surgical treatment offers the best opportunity for complete freedom from seizures. Surgically remediable epilepsy syndromes have been identified, but patients with more complicated epilepsy can also benefit from surgical treatment and require more specialized evaluation, including intracranial EEG monitoring. For patients who are not surgical candidates, or who are unwilling to consider surgery, a variety of other alternative treatments can be considered, including peripheral or central neurostimulation, ketogenic diet, and complementary and alternative approaches. When such alternative treatments are not appropriate or effective, quality of life can still be greatly improved by the psychological and social support services offered by multidisciplinary epilepsy centers. A major obstacle remains the fact that only a small proportion of patients with refractory epilepsy are referred for expert evaluation and treatment.

  18. Refractory overactive bladder: Beyond oral anticholinergic therapy

    Science.gov (United States)

    Glinski, Ronald W.; Siegel, Steven

    2007-01-01

    Objectives: In this review, we discuss the treatment of refractory overactive bladder (OAB) that has not adequately responded to medication therapy and we propose an appropriate care pathway to the treatment of OAB. We also attempt to address the cost of OAB treatments. Materials and Methods: A selective expert review of the current literature on the subject of refractory OAB using MEDLINE was performed and the data is summarized. We also review our experience in treating refractory OAB. The role and outcomes of various treatment options for refractory OAB are discussed and combined therapy with oral anticholinergics is explored. Emerging remedies including intravesical botulinum toxin injection and pudendal neuromodulation are also reviewed, along with conventional surgical options. Results: In general behavioral therapy, pelvic floor electrical stimulation, magnetic therapy and posterior tibial nerve stimulation (PTNS), have shown symptom decreases in 50-80% of patients with OAB. Depending on the study, combination therapy with oral anticholinergics seems to improve efficacy of behavioral therapy and PTNS in approximately 10-30%. In multicenter, long-term randomized controlled trials, sacral neuromodulation has been shown to improve symptoms of OAB and OAB incontinence in up to 80% of the patients treated. Studies involving emerging therapies such as pudendal serve stimulation suggest that there may be a 15-20% increase in efficacy over sacral neuromodulation, but long-term studies are not yet available. Another emerging therapy, botulinum toxin, is also showing similar success in reducing OAB symptoms in 80-90% of patients. Surgical approaches, such as bladder augmentation, are a last resort in the treatment of OAB and are rarely used at this point unless upper tract damage is a concern and all other treatment options have been exhausted. Conclusion: The vast majority of OAB patients can be managed successfully by behavioral options with or without

  19. Refractory overactive bladder: Beyond oral anticholinergic therapy

    Directory of Open Access Journals (Sweden)

    Ronald W Glinski

    2007-01-01

    Full Text Available Objectives: In this review, we discuss the treatment of refractory overactive bladder (OAB that has not adequately responded to medication therapy and we propose an appropriate care pathway to the treatment of OAB. We also attempt to address the cost of OAB treatments. Materials and Methods: A selective expert review of the current literature on the subject of refractory OAB using MEDLINE was performed and the data is summarized. We also review our experience in treating refractory OAB. The role and outcomes of various treatment options for refractory OAB are discussed and combined therapy with oral anticholinergics is explored. Emerging remedies including intravesical botulinum toxin injection and pudendal neuromodulation are also reviewed, along with conventional surgical options. Results: In general behavioral therapy, pelvic floor electrical stimulation, magnetic therapy and posterior tibial nerve stimulation (PTNS, have shown symptom decreases in 50-80% of patients with OAB. Depending on the study, combination therapy with oral anticholinergics seems to improve efficacy of behavioral therapy and PTNS in approximately 10-30%. In multicenter, long-term randomized controlled trials, sacral neuromodulation has been shown to improve symptoms of OAB and OAB incontinence in up to 80% of the patients treated. Studies involving emerging therapies such as pudendal serve stimulation suggest that there may be a 15-20% increase in efficacy over sacral neuromodulation, but long-term studies are not yet available. Another emerging therapy, botulinum toxin, is also showing similar success in reducing OAB symptoms in 80-90% of patients. Surgical approaches, such as bladder augmentation, are a last resort in the treatment of OAB and are rarely used at this point unless upper tract damage is a concern and all other treatment options have been exhausted. Conclusion: The vast majority of OAB patients can be managed successfully by behavioral options with or

  20. Development of diagnosis and repair system for steelmaking refractories; Seikoyo taikabutsu no shindan hoshu gijutsu no kakuritsu

    Energy Technology Data Exchange (ETDEWEB)

    Aso, S.; Harada, S.; Tsutsui, Y. [Nippon Steel Corp., Tokyo (Japan)

    1996-06-01

    The latest measurement equipment and repair method were introduced into the work area of all refractories in the process of torpedo cars, hot metal preliminary treatment, hot metal pans, secondary refining, and cast pans so as to improve the cost of the newest advanced steelmaking refractories. As a result, the refractory cost could be reduced by 10%. This paper introduces the improvement in RH refractories and refractories for hot metal preliminary treatment. As for basic items, in addition to the visual observation, the thickness of refractories was quantified using equipment (laser profile meter, thermotracer, and NS sensor) for the furnace stop in the minimum remaining length. An ITV was also installed in the facilities where the visual check is difficult to carry out. Repair is mainly done by spraying. A thermal spraying repair method with high durability was used for the repair. A method that relieves a thermal shock was used for preheating. Moreover, measures that make the temperature gradient in the thickness direction uniform by using newly developed microwave drying equipment were taken for drying of unburned refractories. 4 refs., 13 figs., 2 tabs.

  1. Bone hydatid disease refractory to nitazoxanide treatment

    NARCIS (Netherlands)

    Schipper, Hans G.; Simsek, Suat; van Agtmael, Michiel A.; van Lienden, Krijn P.

    2009-01-01

    We report a patient with bone hydatid disease that was refractory to both long-term daily treatment with albendazole, combined with cimetidine or administered as monotherapy ( approximately 15 years) and a relatively short course of nitazoxanide combined with albendazole (3 months). Despite

  2. Toll-like receptor 2 expression in refractory periapical lesions.

    Science.gov (United States)

    Desai, S V; Love, R M; Rich, A M; Seymour, G J

    2011-10-01

    To investigate the expression of TLR2 in refractory periapical lesions. Refractory periapical lesion biopsies were histopathologically and clinically categorized into asymptomatic periapical granuloma (n=10), symptomatic periapical granuloma (n=10) or periapical cyst (n=10) and prepared for immunohistochemical staining using antibodies to TLR2, CD3 and CD19 or staining with methyl green pyronin. Sections were viewed under light microscopy and the presence or absence of the target cells was correlated with the histopathological and clinical data. Additionally, TLR2 expression was quantified by counting TLR(+) cells. Various mononuclear inflammatory cells in the bacteria-induced periapical lesions were reactive to TLR2 antibody, with many showing morphological similarities to lymphocytes and plasma cells. Lymphocytes were the most numerous cells in the inflammatory infiltrate. In refractory periapical granuloma, CD3(+) T cells were more numerous, whereas in periapical cysts, CD19(+) B cells were more numerous. There was a statistically significant (Pperiapical granuloma than asymptomatic periapical granuloma or periapical cyst. The presence of TLR-expressing cells in periapical granulomas and cysts provides further evidence that periapical cysts are likely to be sustained by the immune system via reaction to bacterial antigens. © 2011 International Endodontic Journal.

  3. Morphometric brain characterization of refractory obsessive-compulsive disorder: diffeomorphic anatomic registration using exponentiated Lie algebra.

    Science.gov (United States)

    Tang, Wanjie; Li, Bin; Huang, Xiaoqi; Jiang, Xiaoyu; Li, Fei; Wang, Lijuan; Chen, Taolin; Wang, Jinhui; Gong, Qiyong; Yang, Yanchun

    2013-10-01

    Few studies have used neuroimaging to characterize treatment-refractory obsessive-compulsive disorder (OCD). This study sought to explore gray matter structure in patients with treatment-refractory OCD and compare it with that of healthy controls. A total of 18 subjects with treatment-refractory OCD and 26 healthy volunteers were analyzed by MRI using a 3.0-T scanner and voxel-based morphometry (VBM). Diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) was used to identify structural changes in gray matter associated with treatment-refractory OCD. A partial correlation model was used to analyze whether morphometric changes were associated with Yale-Brown Obsessive-Compulsive Scale scores and illness duration. Gray matter volume did not differ significantly between the two groups. Treatment-refractory OCD patients showed significantly lower gray matter density than healthy subjects in the left posterior cingulate cortex (PCC) and mediodorsal thalamus (MD) and significantly higher gray matter density in the left dorsal striatum (putamen). These changes did not correlate with symptom severity or illness duration. Our findings provide new evidence of deficits in gray matter density in treatment-refractory OCD patients. These patients may show characteristic density abnormalities in the left PCC, MD and dorsal striatum (putamen), which should be verified in longitudinal studies. © 2013. Published by Elsevier Inc. All rights reserved.

  4. The degradation of lining of rotary furnaces in the production of zinc oxide

    OpenAIRE

    Natália Luptáková; Evgeniy Anisimov; Františka Pešlová

    2014-01-01

    This paper is closely connected with the complex problem of degradation relating to the refractories of rotary furnace linings in the production of zinc oxide. Zinc oxide can be produced by variety of ways, but the most common method of production which is used in Europe is indirect, i.e. pyrolytic combustion of zinc. This method is also called "French process" of manufacturing ZnO. But this mentioned method of preparation leads to the creation of the enormous amount of zinc slag including ch...

  5. Absorptive coating for aluminum solar panels

    Science.gov (United States)

    Desmet, D.; Jason, A.; Parr, A.

    1979-01-01

    Method for coating forming coating of copper oxide from copper component of sheet aluminum/copper alloy provides strong durable solar heat collector panels. Copper oxide coating has solar absorption characteristics similar to black chrome and is much simpler and less costly to produce.

  6. Medical versus surgical treatment for refractory or recurrent peptic ulcer.

    Science.gov (United States)

    Gurusamy, Kurinchi Selvan; Pallari, Elena

    2016-03-29

    Refractory peptic ulcers are ulcers in the stomach or duodenum that do not heal after eight to 12 weeks of medical treatment or those that are associated with complications despite medical treatment. Recurrent peptic ulcers are peptic ulcers that recur after healing of the ulcer. Given the number of deaths due to peptic ulcer-related complications and the long-term complications of medical treatment (increased incidence of fracture), it is unclear whether medical or surgical intervention is the better treatment option in people with recurrent or refractory peptic ulcers. To assess the benefits and harms of medical versus surgical treatment for people with recurrent or refractory peptic ulcer. We searched the specialised register of the Cochrane Upper GI and Pancreatic Diseases group, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and trials registers until September 2015 to identify randomised trials and non-randomised studies, using search strategies. We also searched the references of included studies to identify further studies. We considered randomised controlled trials and non-randomised studies comparing medical treatment with surgical treatment in people with refractory or recurrent peptic ulcer, irrespective of language, blinding, or publication status for inclusion in the review. Two review authors independently identified trials and extracted data. We planned to calculate the risk ratio, mean difference, standardised mean difference, or hazard ratio with 95% confidence intervals using both fixed-effect and random-effects models with Review Manager 5 based on intention-to-treat analysis. We included only one non-randomised study published 30 years ago in the review. This study included 77 participants who had gastric ulcer and in whom medical therapy (histamine H2 receptor blockers, antacids, and diet) had failed after an average duration of treatment of 29 months. The

  7. Sorption techniques for production of high purity refractory metals

    International Nuclear Information System (INIS)

    Shatalov, V.V.; Peganov, V.A.; Logvinenko, I.A.; Molchanova, T.V.

    2004-01-01

    A consideration is given to potentialities of sorption processes tot provide a high quality of refractory metal and their alloys when using hydrometallurgical methods for raw material processing. The efficiency of application of ion exchange technology is shown for complex solutions reprocessing for various types of polymetallic raw materials, among them uranium ores, enriched concentrates of refractory metal ores, intermediate products, waste solutions. Based on investigation results on the behaviour of elements in process solutions and the mechanism of their sorption and elution, the process of pure chemical compounds production are developed which provide thereafter manufacturing compact metals. The flowsheets developed are mastered on a commercial scale [ru

  8. Response to parenteral iron therapy distinguish unexplained refractory iron deficiency anemia from iron-refractory iron deficiency anemia.

    Science.gov (United States)

    Akin, M; Sarbay, H; Guler, S; Balci, Y I; Polat, A

    2016-04-01

    We evaluated that response to parenteral iron therapy could be helpful in distinguishing the types of iron deficiency anemia. This study analyzed responses to IV iron sucrose therapy of 15 children with unexplained refractory iron deficiency anemia (URIDA). We compared the results at diagnosis, 6 weeks and 6 months after the therapy. Results were compared with responses of 11 patients' results with iron-refractory iron deficiency anemia (IRIDA) from our previous study. Six weeks after the start of treatment, ferritin, MCV, MCH and Hb values were in normal range in 10 patients. The increase in Hb, MCH, MCV, and ferritin values ranged 2.6-3.5 g/dL, 1.7-4.2 pg, 2-9 fL, and 13-25 ng/mL, respectively. In five patients, Hb, MCH, and MCV mean (range) values [11.2 g/dL (11-12.2), 24.5 pg (24-25.6), and 67 fL (65-70)] were nearly normal but ferritin mean (range) values [9.8 ng/mL (8-11)] were below normal. Six weeks after the start of treatment, Hb, MCH, MCV and ferritin values of patients with IRIDA were increased. The increase in Hb, MCH, MCV, and ferritin values ranged 0.8-2.7 g/dL, 1.7-4.2 pg, 2-9 fL, and 13-25 ng/mL, respectively. IRIDA is only partially responsive to parenteral iron supplementation. In conclusion, this study demonstrated that the response to intravenous iron therapy for the URIDA cases improved blood parameters more effectively than hereditary IRIDA. Response to parenteral iron therapy would be helpful to distinguish unexplained refractory IDA from hereditary IRIDA for clinicians who do not have access to hepcidin or TMPRS6 mutation analysis. © 2016 John Wiley & Sons Ltd.

  9. Low-temperature plasma spheroidizing of polydisperse powders of refractory materials

    International Nuclear Information System (INIS)

    Tsymbalist, M.M.; Rudenskaya, N.A.; Kuz'min, B.P.; Pan'kov, V.A.

    2003-01-01

    A model is developed for heating and melting of a spherical particle, when powder processing in low temperature plasma, with the aim of estimation of the dependence of the degree of fusion on particle size for various materials. Spheroidizing of various refractory material powders close in shape and size composition is experimentally performed. Experimental and calculation estimates of spheroidizing criteria for the materials studied are in a satisfactory agreement. The influence of basic physical properties of refractory materials and plasma processing parameters on the degree of particle spheroidizing is analyzed [ru

  10. Colonic exclusion and combined therapy for refractory constipation.

    Science.gov (United States)

    Peng, Hong-Yun; Xu, Ai-Zhong

    2006-12-28

    To investigate the therapeutic effectiveness of colonic exclusion and combined therapy for refractory constipation. Thirty-two patients with refractory constipation were randomly divided into treatment group (n = 14) and control group (n = 18). Fourteen patients in treatment group underwent colonic exclusion and end-to-side colorectal anastomosis. Eighteen patients in control group received subtotal colectomy and end-to-end colorectal anastomosis. The therapeutic effects of the operations were assessed by comparing the surgical time, incision length, volume of blood losses, hospital stay, recovery rate and complication incidence. All patients received long-term follow-up. All operations were successful and patients recovered fully after the operations. In comparison of treatment group and control group, the surgical time (h), incision length (cm), volume of blood losses (mL), hospital stay (d) were 87 +/- 16 min vs 194 +/- 23 min (t = 9.85), 10.4 +/- 0.5 cm vs 21.2 +/- 1.8 cm (t = 14.26), 79.5 +/- 31.3 mL vs 286.3 +/- 49.2 mL (t = 17.24), and 11.8 +/- 2.4 d vs 18.6 +/- 2.6 d (t = 6.91), respectively (P 0.05), 21.4% vs 33.3% (P = 0.73 > 0.05), respectively. Colonic exclusion has better therapeutic efficacy on refractory constipation. It has many advantages such as shorter surgical time, smaller incision, fewer blood losses and shorter hospital stay.

  11. Nonequilibrium iron oxide formation in some low-mass post-asymptotic giant branch stars

    Science.gov (United States)

    Rietmeijer, Frans J. M.

    1992-01-01

    Using experimental evidence that under highly oxidizing conditions gamma-Fe2O3 (maghemite) and Fe3O4 display refractory behavior, it is proposed that very low C/O ratios, that could be unique to evolving AGB stars, induce nonequilibrium formation of ferromagnetic iron oxide grains along with chondritic dust. The oxides are preferentially fractionated from chondritic dust in the stellar magnetic field which could account for the observed extreme iron underabundance in their photosphere. A search for the 1-2.5-micron IR absorption feature, or for diagnostic magnetite and maghemite IR absorption features, could show the validity of the model proposed.

  12. Radiocarbon (14C) Constraints On The Fraction Of Refractory Dissolved Organic Carbon In Primary Marine Aerosol From The Northwest Atlantic

    Science.gov (United States)

    Beaupre, S. R.; Kieber, D. J.; Keene, W. C.; Long, M. S.; Frossard, A. A.; Kinsey, J. D.; Duplessis, P.; Chang, R.; Maben, J. R.; Lu, X.; Zhu, Y.; Bisgrove, J.

    2017-12-01

    Nearly all organic carbon in seawater is dissolved (DOC), with more than 95% considered refractory based on modeled average lifetimes ( 16,000 years) and characteristically old bulk radiocarbon (14C) ages (4000 - 6000 years) that exceed the timescales of overturning circulation. Although this refractory dissolved organic carbon (RDOC) is present throughout the oceans as a major reservoir of the global carbon cycle, its sources and sinks are poorly constrained. Recently, RDOC was proposed to be removed from the oceans through adsorption onto the surfaces of rising bubble plumes produced by breaking waves, ejection into the atmosphere via bubble bursting as a component of primary marine aerosol (PMA), and subsequent oxidation in the atmosphere. To test this mechanism, we used natural abundance 14C (5730 ± 40 yr half-life) to trace the fraction of RDOC in PMA produced in a high capacity generator at two biologically-productive and two oligotrophic hydrographic stations in the Northwest Atlantic Ocean during a research cruise aboard the R/V Endeavor (Sep - Oct 2016). The 14C signatures of PMA separately generated day and night from near-surface (5 m) and deep (2500 m) seawater were compared with corresponding 14C signatures in seawater of near-surface dissolved inorganic carbon (DIC, a proxy for recently produced organic matter), bulk deep DOC (a proxy for RDOC), and near-surface bulk DOC. Results constrain the selectivity of PMA formation from RDOC in natural mixtures of recently produced and refractory DOC. The implications of these results for PMA formation and RDOC biogeochemistry will be discussed.

  13. Corrosion behavior of Al-Fe-sputtering-coated steel, high chromium steels, refractory metals and ceramics in high temperature Pb-Bi

    International Nuclear Information System (INIS)

    Abu Khalid, Rivai; Minoru, Takahashi

    2007-01-01

    Corrosion tests of Al-Fe-coated steel, high chromium steels, refractory metals and ceramics were carried out in high temperature Pb-Bi at 700 C degrees. Oxygen concentrations in this experiment were 6.8*10 -7 wt.% for Al-Fe-coated steels and 5*10 -6 wt.% for high chromium steels, refractory metals and ceramics. All specimens were immersed in molten Pb-Bi in a corrosion test pot for 1.000 hours. Coating was done with using the unbalanced magnetron sputtering (UBMS) technique to protect the steel from corrosion. Sputtering targets were Al and SUS-304. Al-Fe alloy was coated on STBA26 samples. The Al-Fe alloy-coated layer could be a good protection layer on the surface of steel. The whole of the Al-Fe-coated layer still remained on the base surface of specimen. No penetration of Pb-Bi into this layer and the matrix of the specimen. For high chromium steels i.e. SUS430 and Recloy10, the oxide layer formed in the early time could not prevent the penetration of Pb-Bi into the base of the steels. Refractory metals of tungsten (W) and molybdenum (Mo) had high corrosion resistance with no penetration of Pb-Bi into their matrix. Penetration of Pb-Bi into the matrix of niobium (Nb) was observed. Ceramic materials were SiC and Ti 3 SiC 2 . The ceramic materials of SiC and Ti 3 SiC 2 had high corrosion resistance with no penetration of Pb-Bi into their matrix. (authors)

  14. Lightweight cordierite–mullite refractories with low coefficients of ...

    Indian Academy of Sciences (India)

    of thermal conductivity and high mechanical properties ... compositions and microstructures of lightweight refractories were measured by X-ray .... of matrices were determined by calibration with EDAX ZAF .... Guzman I Ya 2003 Glass Ceram.

  15. Antipsychotic Polypharmacy in a Treatment-Refractory Schizophrenia Population Receiving Adjunctive Treatment With Electroconvulsive Therapy

    DEFF Research Database (Denmark)

    Kristensen, Diana; Hageman, Ida; Bauer, Jeanett

    2013-01-01

    Antipsychotic polypharmacy (APP) is frequent, but its pattern is unknown in treatment-refractory schizophrenia-spectrum patients receiving electroconvulsive therapy (ECT).......Antipsychotic polypharmacy (APP) is frequent, but its pattern is unknown in treatment-refractory schizophrenia-spectrum patients receiving electroconvulsive therapy (ECT)....

  16. Refractory oxides containing aluminium and barium Oxidos refratários contendo alumínio e bário

    Directory of Open Access Journals (Sweden)

    T. J. Davies

    1998-10-01

    Full Text Available Oxides containing aluminium and barium, optionally with chromium, are refractory with several possible industrial uses. A gel precursor of an oxide having the formula BaO.n(Al2xCr2yO3, where 1Oxidos contendo alumínio e bário, opcionalmente com crômio, são refratários com vários possíveis usos industriais. Foi preparado um gel precursor de um óxido de formula BaO.n(Al2xCr2yO3, com 1

  17. Morphological differentiation of severe aplastic anaemia from hypocellular refractory cytopenia of childhood

    DEFF Research Database (Denmark)

    Baumann, Irith; Führer, Monika; Behrendt, Sonja

    2012-01-01

    To evaluate the reproducibility and reliability of the histomorphological criteria differentiating severe aplastic anaemia (SAA) and hypoplastic refractory cytopenia of childhood (RCC), the most frequently acquired hypocellular bone marrow conditions of childhood.......To evaluate the reproducibility and reliability of the histomorphological criteria differentiating severe aplastic anaemia (SAA) and hypoplastic refractory cytopenia of childhood (RCC), the most frequently acquired hypocellular bone marrow conditions of childhood....

  18. Advances in multidisciplinary individualized treatment of refractory hepatic alveolar echinococcosis

    Directory of Open Access Journals (Sweden)

    ABUDUAINI Abulizi

    2015-04-01

    Full Text Available Hepatic alveolar echinococcosis (HAE is a zoonotic parasitic disease that seriously threatens the population in western China and compromises patients′ quality of life. With the continuous improvement in radical resection rate in recent years, late-stage HAE patients that were incurable in the past now have the opportunity for radical resection. However, patients who are not suitable candidates for radical resection still suffer from various complications and poor quality of life. Therefore, HAE is still considered a refractory and complex disease. The simple empirical treatment model provided by traditional professional discussion is unable to satisfy the treatment of advanced refractory HAE as it is unable to integrate specialized, standardized clinical skills for diagnosis and treatment. Multidisciplinary individualized treatment (MDT organically integrates the advantages of the available treatment into a reasonable individualized comprehensive treatment regimen. This review summarizes the advances in MDT for HAE as the best option to increase long-term survival, and suggests MDT as the first-line treatment for late-stage refractory hepatic alveolar echinococcosis.

  19. Immunomodulatory therapy in refractory/recurrent ovarian cancer

    Directory of Open Access Journals (Sweden)

    Chao-Yu Chen

    2015-04-01

    Conclusion: IMT alone or add-on to palliative/salvage chemotherapy for refractory/recurrent EOC achieves a substantial disease stabilizing rate without severe toxicity, which might be a potential option in selected patients. The ALC 1 month after IMT could be an early indicator to disease stabilization.

  20. Decision Making during the Psychological Refractory Period

    NARCIS (Netherlands)

    Zylberberg, Ariel; Ouellette, Brian; Sigman, Mariano; Roelfsema, Pieter R.

    2012-01-01

    In spite of its massively parallel architecture [1], the human brain is fundamentally limited if required to perform two tasks at the same time [2, 3]. This limitation can be studied with the psychological refractory period (PRP) paradigm, where two stimuli that require speeded responses occur in

  1. Ways to improve physical and thermal performance of refractory lining materials

    Directory of Open Access Journals (Sweden)

    Khlystov A.I.

    2017-01-01

    Full Text Available Refractory lining materials, which include ceramic refractories and nonfired heat-resistant concretes, have a very short lifespan during the turnaround time measured in years and sometimes months. Therefore, increasing the service life of thermal generating units by 1.5-2 times will bring significant economic benefits. The main factor that determines the durability of refractory lining materials is the thermal resistance. It is possible to increase the thermal resistance by improving such physical and mechanical properties as strength and density. As for the ceramic refractory performance improvement, such technological methods as their structural and chemical modification by phosphate binder impregnation, as well as introduction of phosphate components into the ceramic batches during the molding process increase, in particular, their thermal stability. The use of aluminous and high-alumina cements contributes to a significant increase of not only strength, but also physical and thermal performance of heat-resistant concretes with different fillers. Switching to the use of chemical binders in the compositions of heat-resistant concretes (liquid glass with effective hardeners; silicate-block and phosphate binders enables to develop high-heat resistant materials which do not soften in a wide range of heating temperatures from 400 °С to 1600 °С. The positive results on increasing the thermal resistance of heat-resistant composites can be obtained by reinforcing them with high temperature fibers.

  2. CAR-T cells and allogeneic hematopoietic stem cell transplantation for relapsed/refractory B-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Liu, Jun; Zhang, Xi; Zhong, Jiang F; Zhang, Cheng

    2017-10-01

    Relapsed/refractory acute lymphoblastic leukemia (ALL) has a low remission rate after chemotherapy, a high relapse rate and poor long-term survival even when allogeneic hematopoietic stem cell transplantation (allo-HSCT) is performed. Chimeric antigen receptors redirected T cells (CAR-T cells) can enhance disease remission with a favorable outcome for relapsed/refractory ALL, though some cases quickly relapsed after CAR-T cell treatment. Thus, treatment with CAR-T cells followed by allo-HSCT may be the best way to treat relapsed/refractory ALL. In this review, we first discuss the different types of CAR-T cells. We then discuss the treatment of relapsed/refractory ALL using only CAR-T cells. Finally, we discuss the use of CAR-T cells, followed by allo-HSCT, for the treatment of relapsed/refractory ALL.

  3. Rate of primary refractory disease in B and T-cell non-Hodgkin's lymphoma: correlation with long-term survival.

    Directory of Open Access Journals (Sweden)

    Corrado Tarella

    Full Text Available BACKGROUND: Primary refractory disease is a main challenge in the management of non-Hodgkin's Lymphoma (NHL. This survey was performed to define the rate of refractory disease to first-line therapy in B and T-cell NHL subtypes and the long-term survival of primary refractory compared to primary responsive patients. METHODS: Medical records were reviewed of 3,106 patients who had undergone primary treatment for NHL between 1982 and 2012, at the Hematology Centers of Torino and Bergamo, Italy. Primary treatment included CHOP or CHOP-like regimens (63.2%, intensive therapy with autograft (16.9%, or other therapies (19.9%. Among B-cell NHL, 1,356 (47.8% received first-line chemotherapy with rituximab. Refractory disease was defined as stable/progressive disease, or transient response with disease progression within six months. RESULTS: Overall, 690 (22.2% patients showed primary refractory disease, with a higher incidence amongst T-cell compared to B-cell NHL (41.9% vs. 20.5%, respectively, p<0.001. Several other clinico-pathological factors at presentation were variably associated with refractory disease, including histological aggressive disease, unfavorable clinical presentation, Bone Marrow involvement, low lymphocyte/monocyte ration and male gender. Amongst B-cell NHL, the addition of rituximab was associated with a marked reduction of refractory disease (13.6% vs. 26.7% for non-supplemented chemotherapy, p<0.001. Overall, primary responsive patients had a median survival of 19.8 years, compared to 1.3 yr. for refractory patients. A prolonged survival was consistently observed in all primary responsive patients regardless of the histology. The long life expectancy of primary responsive patients was documented in both series managed before and after 2.000. Response to first line therapy resulted by far the most predictive factor for long-term outcome (HR for primary refractory disease: 16.52, p<0.001. CONCLUSION: Chemosensitivity to primary

  4. Clinical observation on Ahmed glaucoma valve implantation for teenagers with refractory glaucoma

    Directory of Open Access Journals (Sweden)

    Dong-Dao Song

    2016-06-01

    Full Text Available AIM:To observe the clinical effect of Ahmed glaucoma valve(AGVimplantation for teenagers with refractory glaucoma. METHODS: Twenty-seven patients(27 eyeswith refractory glaucoma were treated with AGV implantation in our hospital from October 2012 to October 2014. The patients were followed up for 12mo. The success rate of the operation, postoperative intraocular pressure, the best corrected visual acuity, as well as complications were recorded. RESULTS: The success rate of the operation was 85%. The intraocular pressure of the 27 patients decreased from 48.3±8.3mmHg before operations to 21.4±8.1mmHg(PPCONCLUSION: AGV implantation is characterized by a high success rate, simple operation, less complications and is an effective treatment for refractory glaucoma in adolescents.

  5. Corrosion of K-3 glass-contact refractory in sodium-rich aluminosilicate melts

    International Nuclear Information System (INIS)

    Lu, X.D.; Gan, H.; Buechele, A.C.; Pegg, I.L.

    1999-01-01

    The corrosion of the glass-contact refractory Monofrax K-3 in two sodium-rich aluminosilicate melts has been studied at 1,208 and 1,283 C using a modified ASTM procedure with constant agitation of the melt by air bubbling. The results for the monolithic refractory indicate a fast initial stage involving phase dissolution and transformation and a later passivated stage in which the surface of the refractory has been substantially modified. The composition of the stable spinel phase in the altered layer on monolithic coupons of K-3 is almost identical to the equilibrium composition bracketed by the dissolution of powdered K-3 into under-saturated melts on the other. The temperature and melt shear viscosity were found to have significant effects on the rates of K-3 dissolution and transformation

  6. A retrospective study on the management of patients with rituximab refractory follicular lymphoma.

    Science.gov (United States)

    Solal-Céligny, Philippe; Leconte, Pierre; Bardet, Aurélie; Hernandez, Juana; Troussard, Xavier

    2018-01-01

    Given that there are currently no clear recommendations regarding therapeutic options for rituximab refractory/relapsed follicular lymphoma patients, this study aimed to describe the real-life management of patients with refractory follicular lymphoma after systemic rituximab-containing regimens (rFL), and rFL patient characteristics. In this retrospective, national, multicentre study, descriptive analyses were mainly performed according to rituximab-containing regimen at rFL diagnosis [rituximab monotherapy (R-MONO), rituximab + chemotherapy (R-COMBO), and ongoing rituximab maintenance (R-MAINTAIN)]. The 459 analysed patients experienced rituximab-refractoriness between October 2013 and September 2015: R-MONO: 58 (13%), R-COMBO: 197 (43%), R-MAINTAIN: 204 (44%). Post-refractoriness strategies were heterogeneous: idelalisib ± rituximab (22%), without anti-lymphoma treatment (21%), rituximab-chemotherapy (21%) and stem cell transplantation (18%). Rituximab was continued in combination in 41% of cases. Chosen strategies varied according to patient age (without anti-lymphoma treatment: 28% of patients if ≥65 years vs. 12% if management and for the design of clinical trials in these patients. © 2017 John Wiley & Sons Ltd.

  7. Classical management of refractory adult immune (idiopathic) thrombocytopenic purpura.

    Science.gov (United States)

    McMillan, R

    2002-03-01

    Treatment of chronic immune (idiopathic) thrombocytopenic purpura with corticosteroids and/or splenectomy results in safe platelet counts in over 70% of patients without additional treatment. Therapy of patients who are refractory to these two treatments may be difficult. The treatment approach to refractory ITP patients, described in this report, is arbitrarily divided into four levels: levels 1 through 3 represent treatments with increasing side effects; level 4 therapy may be tried when the others have failed. Patients undergoing these treatments may require concomitant intravenous gammaglobulin, high-dose corticosteroids or platelets, to maintain the platelet count in the setting of mucosal bleeding or severe thrombocytopenia. Copyright 2002, Elsevier Science Ltd. All rights reserved.

  8. Refractory Septic Shock Treated with Nephrectomy under the Support of Extracorporeal Membrane Oxygenation

    Directory of Open Access Journals (Sweden)

    Young Kun Lee

    2015-08-01

    Full Text Available Conventional medical therapies have not been very successful in treating adults with refractory septic shock. The effects of direct hemoperfusion using polymyxin B and veno-arterial extracorporeal membrane oxygenation (ECMO for refractory septic shock remain uncertain. A 66-year-old man was admitted to the emergency department and suffered from sepsis-induced hemodynamic collapse. For hemodynamic improvement, we performed direct hemoperfusion using polymyxin B. Computed tomography scan of this patient revealed emphysematous pyelonephritis (EPN, for which he underwent emergent nephrectomy with veno-arterial ECMO support. To the best of our knowledge, this is the first report of successful treatment of EPN with refractory septic shock using polymyxin B hemoperfusion and nephrectomy under the support of ECMO.

  9. Characterization of oxide scales grown on alloy 310S stainless steel after long term exposure to supercritical water at 500 °C

    Energy Technology Data Exchange (ETDEWEB)

    Behnamian, Yashar, E-mail: behnamia@ualberta.ca [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Mostafaei, Amir [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Kohandehghan, Alireza [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Amirkhiz, Babak Shalchi [Canmet MATERIALS, Natural Resources Canada, Hamilton, Ontario L8P 0A5 (Canada); Serate, Daniel [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Zheng, Wenyue [Canmet MATERIALS, Natural Resources Canada, Hamilton, Ontario L8P 0A5 (Canada); Guzonas, David [Canadian Nuclear Laboratories, Chalk River Laboratories, Chalk River, Ontario K0J 1J0 (Canada); Chmielus, Markus [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Chen, Weixing, E-mail: Weixing@ualberta.ca [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada); Luo, Jing Li, E-mail: Jingli.luo@ualberta.ca [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9 (Canada)

    2016-10-15

    The oxide scale grown of static capsules made of alloy 310S stainless steel was investigated by exposure to the supercritical water at 500 °C 25 MPa for various exposure times up to 20,000 h. Characterization techniques such as X-ray diffraction, scanning/transmission electron microscopy, energy dispersive spectroscopy, and fast Fourier transformation were employed on the oxide scales. The elemental and phase analyses indicated that long term exposure to the SCW resulted in the formation of scales identified as Fe{sub 3}O{sub 4} (outer layer), Fe-Cr spinel (inner layer), Cr{sub 2}O{sub 3} (transition layer) on the substrate, and Ni-enrichment (chrome depleted region) in the alloy 310S. It was found that the layer thickness and weight gain vs. exposure time followed parabolic law. The oxidation mechanism and scales grown on the alloy 310S stainless steel exposed to SCW are discussed. - Highlights: •Oxidation of alloy 310S stainless steel exposed to SCW (500 °C/25 MPa) •The layer thickness and weight gain vs. exposure time followed parabolic law. •Oxide layers including Fe{sub 3}O{sub 4} (outer), Fe-Cr spinel (inner) and Cr{sub 2}O{sub 3} (transition) •Ni element is segregated by the selective oxidation of Cr.

  10. Nitric-glycolic flowsheet reduction/oxidation (redox) model for the defense waste processing facility (DWPF)

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Williams, M. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Trivelpiece, C. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Ramsey, W. G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-06-14

    Control of the REDuction/OXidation (REDOX) state of glasses containing high concentrations of transition metals, such as High Level Waste (HLW) glasses, is critical in order to eliminate processing difficulties caused by overly reduced or overly oxidized melts. Operation of a HLW melter at Fe+2/ΣFe ratios of between 0.09 and 0.33, retains radionuclides in the melt and thus the final glass. Specifically, long-lived radioactive 99Tc species are less volatile in the reduced Tc4+ state as TcO2 than as NaTcO4 or Tc2O7, and ruthenium radionuclides in the reduced Ru4+ state are insoluble RuO2 in the melt which are not as volatile as NaRuO4 where the Ru is in the +7 oxidation state. Similarly, hazardous volatile Cr6+ occurs in oxidized melt pools as Na2CrO4 or Na2Cr2O7, while the Cr+3 state is less volatile and remains in the melt as NaCrO2 or precipitates as chrome rich spinels. The melter REDOX control balances the oxidants and reductants from the feed and from processing additives such as antifoam.

  11. Iatrogenic colorectal Kaposi sarcoma complicating a refractory ...

    African Journals Online (AJOL)

    Kaposi sarcoma is a mesenchymal tumor associated to a human herpes virus-8. It often occurs in human immunodeficiency virus-positive subjects. Colorectal localization is rare. We report the case of a colorectal Kaposi sarcoma complicating a refractory ulcerative colitis treated with surgery after the failure of ...

  12. Efficacy and Safety of Rituximab in Children with Refractory Nephrotic Syndrome; A Multicenter Clinical Trial

    Directory of Open Access Journals (Sweden)

    Yo Han Ahn

    2014-06-01

    Conclusions: In this interim analysis of clinical trial to evaluate the efficacy and safety of RTX in children with refractory NS, RTX treatment for refractory NS was safe and effective, especially in patients with DNS.

  13. Evaluation of nutritional status in children with refractory epilepsy.

    Science.gov (United States)

    Bertoli, S; Cardinali, S; Veggiotti, P; Trentani, C; Testolin, G; Tagliabue, A

    2006-04-26

    children affected by refractory epilepsy could be at risk of malnutrition because of feeding difficulties (anorexia, chewing, swallowing difficulties or vomiting) and chronic use of anticonvulsants, which may affect food intake and energy metabolism. Moreover, their energy requirement may be changed as their disabilities would impede normal daily activities. The aim of the present study was to evaluate nutritional status, energy metabolism and food intake in children with refractory epilepsy. 17 children with refractory epilepsy (13 boys and 4 girls; mean age 9 +/- 3,2 years; Body Mass Index 15,7 +/- 3,6) underwent an anthropometric assessment, body composition evaluation by dual-energy X-ray absorptiometry, detailed dietetic survey and measurement of resting energy expenditure by indirect calorimetry. Weight-for-age, height-for-age (stunting) and weight-for-height (wasting) were estimated compared to those of a reference population of the same age. 40% of children were malnourished and 24% were wasted. The nutritional status was worse in the more disabled children. Dietary intake resulted unbalanced (18%, 39%, 43% of total daily energy intake derived respectively from protein, lipid and carbohydrate). Adequacy index [nutrient daily intake/recommended allowance (RDA) x 100] was nutritional assessment and management as part of their overall care.

  14. Adalimumab for the treatment of refractory noninfectious paediatric uveitis.

    Science.gov (United States)

    Muñoz-Gallego, Alicia; Barral, Estefanía; Enríquez, Eugenia; Tejada, Pilar; Barceló, Ana; de Inocencio, Jaime

    2017-06-01

    To report the experience of our center with the use of adalimumab (ADA) for the treatment of severe refractory noninfectious paediatric uveitis. The study is a retrospective case series of all paediatric patients with refractory uveitis who were treated with ADA at the Paediatric Uveitis Unit of our center from 2008 to 2015. We present 12 patients (6 Juvenile idiopathic arthritis-associated uveitis, 4 idiopathic panuveitis, 1 early-onset sarcoidosis-associated panuveitis, and 1 intermediate uveitis), with uveitis in 19/24 eyes. Once ADA therapy was started, all the patients presented improved activity according to Standardization of Uveitis Nomenclature (SUN) criteria. Nine out of the 12 patients had structural damage before ADA could be started: cataract (n = 4), glaucoma (n = 2), cystic macular edema (n = 1), exudative retinal detachment (n = 1), and optic disk edema (n = 5). Visual acuity improved or maintained stable in 17/19 affected eyes, and only 2 eyes decreased its visual acuity because of structural damage, which was already present before ADA therapy. In our experience, ADA presents a good safety profile and is efficacious in the treatment of paediatric patients with different forms of refractory noninfectious uveitis.

  15. Evaluation of nutritional status in children with refractory epilepsy

    Science.gov (United States)

    Bertoli, S; Cardinali, S; Veggiotti, P; Trentani, C; Testolin, G; Tagliabue, A

    2006-01-01

    Background children affected by refractory epilepsy could be at risk of malnutrition because of feeding difficulties (anorexia, chewing, swallowing difficulties or vomiting) and chronic use of anticonvulsants, which may affect food intake and energy metabolism. Moreover, their energy requirement may be changed as their disabilities would impede normal daily activities. The aim of the present study was to evaluate nutritional status, energy metabolism and food intake in children with refractory epilepsy. Methods 17 children with refractory epilepsy (13 boys and 4 girls; mean age 9 ± 3,2 years; Body Mass Index 15,7 ± 3,6) underwent an anthropometric assessment, body composition evaluation by dual-energy X-ray absorptiometry, detailed dietetic survey and measurement of resting energy expenditure by indirect calorimetry. Weight-for-age, height-for-age (stunting) and weight-for-height (wasting) were estimated compared to those of a reference population of the same age. Results 40% of children were malnourished and 24% were wasted. The nutritional status was worse in the more disabled children. Dietary intake resulted unbalanced (18%, 39%, 43% of total daily energy intake derived respectively from protein, lipid and carbohydrate). Adequacy index [nutrient daily intake/recommended allowance (RDA) × 100] was nutritional assessment and management as part of their overall care. PMID:16640779

  16. NOS module - reducing the nitrogen oxides and dust emissions of wood-fired systems; NOS-Modul. Installation und Test - Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Salerno, B.

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the potential of reducing dust and nitrogen oxides emissions of biomass-fired systems. Two prototype installations are described with capacities of 70 - 300 kW and 150 - 500 kW, the latter being a mobile installation installed together with a silo in a container. The prototypes can burn problematical biomass such as cereals, chicken droppings, damp wood-chippings and straw. Various factors and configurations influencing the formation of emissions are examined. Cyclone technology, a catalyst using chrome-nickel shavings and a ceramic heat-exchanger are discussed. Measurements made are presented in tabular and graphical form and discussed.

  17. Sub-micrometer refractory carbonaceous particles in the polar stratosphere

    Science.gov (United States)

    Schütze, Katharina; Wilson, James Charles; Weinbruch, Stephan; Benker, Nathalie; Ebert, Martin; Günther, Gebhard; Weigel, Ralf; Borrmann, Stephan

    2017-10-01

    Eleven particle samples collected in the polar stratosphere during SOLVE (SAGE III Ozone loss and validation experiment) from January until March 2000 were characterized in detail by high-resolution transmission and scanning electron microscopy (TEM/SEM) combined with energy-dispersive X-ray microanalysis. A total of 4202 particles (TEM = 3872; SEM = 330) were analyzed from these samples, which were collected mostly inside the polar vortex in the altitude range between 17.3 and 19.9 km. Particles that were volatile in the microscope beams contained ammonium sulfates and hydrogen sulfates and dominated the samples. Some particles with diameters ranging from 20 to 830 nm were refractory in the electron beams. Carbonaceous particles containing additional elements to C and O comprised from 72 to 100 % of the refractory particles. The rest were internal mixtures of these materials with sulfates. The median number mixing ratio of the refractory particles, expressed in units of particles per milligram of air, was 1.1 (mg air)-1 and varied between 0.65 and 2.3 (mg air)-1. Most of the refractory carbonaceous particles are completely amorphous, a few of the particles are partly ordered with a graphene sheet separation distance of 0.37 ± 0.06 nm (mean value ± standard deviation). Carbon and oxygen are the only detected major elements with an atomic O/C ratio of 0.11 ± 0.07. Minor elements observed include Si, S, Fe, Cr and Ni with the following atomic ratios relative to C: Si/C: 0.010 ± 0.011; S/C: 0.0007 ± 0.0015; Fe/C: 0.0052 ± 0.0074; Cr/C: 0.0012 ± 0.0017; Ni/C: 0.0006 ± 0.0011 (all mean values ± standard deviation).High-resolution element distribution images reveal that the minor elements are distributed within the carbonaceous matrix; i.e., heterogeneous inclusions are not observed. No difference in size, nanostructure and elemental composition was found between particles collected inside and outside the polar vortex. Based on chemistry and nanostructure

  18. Wetting of refractory metals with copper base alloys

    International Nuclear Information System (INIS)

    Anikeev, E.F.; Kostikov, V.I.; Chepelenko, V.N.; Batov, V.M.

    1978-01-01

    The effect is studied of phosphorus upon the wetting of molybdenum, niobium and tantalum by an alloy of the system copper-silver (10%) as a function of contact time and phosphorus concentration. Experiments have been conducted in vacuum of 5x10 -4 mm Hg at 900 deg C. It is established that the introduction of phosphorus into a copper-silver alloy improves the wetting of molybdenum, niobium and tantalum. Formation of intermetallic compounds on the alloy-refractory metal interface can be avoided by adjusting the time of contact of the solder with molybdenum, niobium and tantalum. As a solder with 2.9% phosphorus spreads well over copper, it is suggested to use said solder for brazing copper and the investigated refractory metals in items intended for service at temperatures of up to 600 deg C

  19. Refractory compounds for repairing coke-oven brickwork

    Energy Technology Data Exchange (ETDEWEB)

    Hanganu, M.; Dragomir, C. (and others)

    1984-01-01

    A number of refractory compounds are presented, based on aluminium phosphate, phosphoric acid, sodium silicate and fire-clay and mullitic zirconium mastic, including their composition, properties and application (by impregnation, spray application or pouring), which are suitable for repairing various types of coke-oven brickwork. The results obtained are given.

  20. Carboxyhemoglobin formation secondary to nitric oxide therapy in the setting of interstitial lung disease and pulmonary hypertension.

    Science.gov (United States)

    Ruisi, Phillip; Ruisi, Michael

    2011-01-01

    Carbon monoxide (CO) has been widely recognized as an exogenous poison, although endogenous mechanisms for its formation involve heme-oxygenase (HO) isoforms, more specifically HO-1, in the setting of oxidative stress such as acute respiratory distress syndrome, sepsis, trauma, and nitric oxide use have been studied. In patients with refractory hypoxemia, inhaled nitric oxide (iNO) therapy is used to selectively vasodilate the pulmonary vasculature and improve ventilation-perfusion match. Inhaled nitric oxide is rapidly inactivated on binding to hemoglobin in the formation of nitrosyl- and methemoglobin in the pulmonary vasculature. Hence, inhaled nitric oxide has minimal systemic dissemination. Several experimental design studies involving lab rats have demonstrated increased levels of carboxyhemoglobin and exhaled CO as a result of nitric oxide HO-1 induction.