WorldWideScience

Sample records for bituminous surface treatment

  1. Pre-treatment of bituminized NPP wastes for disposal in near-surface repository

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Vanessa Mota; Tello, Clédola Cássia Oliveira de, E-mail: vanessamotavieira@gmail.com, E-mail: tellocc@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    The implementation of the national repository is an important technical requirement, and a legal requirement for the entry into operation of the nuclear power plant Angra 3. The Brazilian repository is being planned to be a near-surface one. In Brazil the low and intermediate level radioactive wastes are immobilized using cement and bitumen for Angra 1 and Angra 2 NPP, respectively. The main problems due to the disposal of bituminized wastes in repositories are swelling of the waste products and their degradation in the long term. To accommodate the swelling of the bituminized wastes, the drums are filled up to 70 - 90% of their volume, which reduces the structural the repository stability and the disposal availability. Countries, which use bitumen in the solidification of NPP's radioactive waste and have near-surface repositories, need to immobilize this bituminized waste within other drums containing cement pastes or mortars to disposal them. This study aims to find solutions for the storage in surface repository of bituminized radioactive waste products, making them compatible with the acceptance criteria of cemented waste products. It was also performed a modeling with the results obtained in the leaching test using the ALT program and defined the transport model of the cesium leachate element and it was verified that in the early times the leaching was governed by the diffusion model and later by the partition model. The results obtained in this study can be used in the evaluation of performance of repositories. (author)

  2. Skid resistance of bituminous surfaces in Ohio

    Science.gov (United States)

    Colony, D. C.

    1984-03-01

    Statistical studies of skid number (SN) on the state highway system in Ohio reveal apparently systematic variations in distributions of SN among the twelve districts in the state. These variations appear to be significantly related to traffic and to geological characteristics of a given district. Regression calculations using traffic index, a function of ADT and age of the pavement surface in months, show a high correlation with SN, although standard errors of estimate were too large to make the equations useful for predicting SN from traffic variables. Similar results were obtained by elating SN to physiographic features in the state. Pavement surface type (bituminous or pcc) and coarse aggregate type (limestone, gravel or slag) are significantly related to SN.

  3. Design of bituminous surface mixes with high skid resistance.

    Science.gov (United States)

    1974-01-01

    The Virginia Highway Research Council has proposed a study of the skid resistance of bituminous surfaces incorporating relatively hard and expensive aggregates. The hardness of the aggregates to be used aluminum oxide (Exolon) and calcined kaolin -- ...

  4. Identification of aggregates for Tennessee bituminous surface courses

    Science.gov (United States)

    Sauter, Heather Jean

    Tennessee road construction is a major venue for federal and state spending. Tax dollars each year go to the maintenance and construction of roads. One aspect of highway construction that affects the public is the safety of its state roads. There are many factors that affect the safety of a given road. One factor that was focused on in this research was the polish resistance capabilities of aggregates. Several pre-evaluation methods have been used in the laboratory to predict what will happen in a field situation. A new pre-evaluation method was invented that utilized AASHTO T 304 procedure upscaled to accommodate surface bituminous aggregates. This new method, called the Tennessee Terminal Textural Condition Method (T3CM), was approved by Tennessee Department of Transportation to be used as a pre-evaluation method on bituminous surface courses. It was proven to be operator insensitive, repeatable, and an accurate indication of particle shape and texture. Further research was needed to correlate pre-evaluation methods to the current field method, ASTM E 274-85 Locked Wheel Skid Trailer. In this research, twenty-five in-place bituminous projects and eight source evaluations were investigated. The information gathered would further validate the T3CM and find the pre-evaluation method that best predicted the field method. In addition, new sources of aggregates for bituminous surface courses were revealed. The results of this research have shown T3CM to be highly repeatable with an overall coefficient of variation of 0.26% for an eight sample repeatability test. It was the best correlated pre-evaluation method with the locked wheel skid trailer method giving an R2 value of 0.3946 and a Pearson coefficient of 0.710. Being able to predict field performance of aggregates prior to construction is a powerful tool capable of saving time, money, labor, and possibly lives.

  5. Surface Properties of Photo-Oxidized Bituminous Coals: Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    Natural weathering has a detrimental effect on the hydrophobic nature of coal, which in turn can influence clean-coal recovery during flotation. Few techniques are available that can establish the quality of coal surfaces and that have a short analysis time to provide input for process control. Luminescence emissions which can be quantified with an optical microscope and photometer system, are measurably influenced by degree of weathering as well as by mild storage deterioration. In addition, it has been shown that when vitrinite is irradiated with a relatively high intensity flux of violet- or ultraviolet- light in the presence of air, photo-oxidation of the surface occurs. The combination of measuring the change in luminescence emission intensity with degree of surface oxidation provided the impetus for the current investigation. The principal aim of this research was to determine whether clear correlations could be established among surface oxygen functionality, hydrophobicity induced by photo-oxidation, and measurements of luminescence intensity and alteration. If successful, the project would result in quantitative luminescence techniques based on optical microscopy that would provide a measure of the changes in surface properties as a function of oxidation and relate them to coal cleanability. Two analytical techniques were designed to achieve these goals. Polished surfaces of vitrain bands or a narrow size fraction of powdered vitrain concentrates were photo-oxidized using violet or ultraviolet light fluxes and then changes in surface properties and chemistry were measured using a variety of near-surface analytical techniques. Results from this investigation demonstrate that quantitative luminescence intensity measurements can be performed on fracture surfaces of bituminous rank coals (vitrains) and that the data obtained do reveal significant variations depending upon the level of surface oxidation. Photo-oxidation induced by violet or ultraviolet light

  6. Characterize Cold Bituminous Emulsion Mixtures Incorporated Ordinary Portland Cement Filler for Local Surface Layer

    Directory of Open Access Journals (Sweden)

    Mustafa Amoori Kadhim

    2018-02-01

    Full Text Available Cold Bituminous Emulsion Mixtures have many environmental, logistical, and economic advantages over conventional Hot Mix Asphalt. Nevertheless, their inferior performance and high water sensitivity at early life attract little attentions. Moreover, it is impossible to apply CBEM as a structural surface layer if left without treatment or enhancement. The main aim of this study is to enhance the properties of CBEM for the hope of using it as a structural layer. Thus, a trial has been made to improve CBEM mechanical and durability properties by replacing the Ordinary Portland Cement by the Conventional Mineral Filler with 3 percentages; namely, 0, 50%, and 100%. CBEM mixtures mechanical properties were evaluated in term of Marshall Stability and Flow, Indirect Tensile Strength, and Wheel Track Test. While Moisture damage was evaluated in terms of Retained Marshall Stability. Test results showed that the addition of 100%OPC filler can improve CBEM mechanical and durability properties efficiently. In terms of mechanical properties results, CBEM comprised 100%OPC, can be used as a structural Surface layer based on local Iraqi specifications limits, where mixture enhanced about 1.9, 1.78, 9,4.85, and 2.6  times in term of MS, MF, rutting deformation resistance, resistance to tensile cracking, and moisture damage resistance, respectively as compared to untreated CBEM. Also, CBEM-100%OPC mix seemed comparable (and sometime superior to HMA, e.g., resistance to rutting of CBEM is about 6.2 times higher than that of HMA. It’s worth to say that OPC upgrades CBEM to a significant level that enables it to use as a structural layer in terms of the mechanical and the durability properties.

  7. Appropriate use of locally available materials in concrete, bituminous surfacings and layerworks for roads in rural areas

    CSIR Research Space (South Africa)

    Paige-Green, P

    2009-06-17

    Full Text Available and durability of the concrete and probably to increase the shrinkage. Bituminous surfacings are currently tightly specified and comparison with other countries indicates that certain areas of relaxation are possible. These are mostly with respect to the grading...

  8. Surface composition of silica particles embedded in an Australian bituminous coal.

    Science.gov (United States)

    Gong, B; Pigram, P J; Lamb, R N

    1999-07-01

    The composition and structure of the surface layers of a series of silica particles (10-20 microns across), embedded in a bituminous coal from the Whybrow seam, Sydney Basin, Australia, have been characterized in situ using time-of-flight secondary ion mass spectrometry (TOFSIMS), ion imaging, and depth profiling. The silica particles investigated are typically encased in a multilayered shell, the composition of which differs from average composition of both the silica and the bulk coal. The analysis directly demonstrates the presence of a silanol-rich (Si-OH) interfacial layer 3 nm in thickness. This silanol-rich region separates the bulk silica and a complex non-silica layer encasing the particles. The interfacial region also shows significant lithium enrichment (approximately fivefold over bulk) which implies diffusion and precipitation of lithium-containing species during the authigenetic formation of the surface layers of the silica grains. The outer layer encasing the silica particles is 10 nm in thickness and is composed of clays and carbonates, and, in some cases, includes organic material. The elemental constituents of this layer include aluminium, sodium, potassium, magnesium, iron, and lesser amounts of titanium and copper. The variation in the aluminium concentration from the outermost surface to the deeper layers is less than that of other non-silica species. A relatively high amount of calcium is found associated with the silica bulk. Although only non-respirable-sized silica particles are examined in this work, the methods of analysis developed have potential in providing an insight into the surface composition of respirable particles and in further studies of the surface bioavailability of silica species.

  9. 30 CFR 716.4 - Special bituminous coal mines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special bituminous coal mines. 716.4 Section... INTERIOR INITIAL PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.4 Special bituminous coal mines. (a) Definition. Special bituminous coal surface mines as used in this section means those bituminous...

  10. Treatments for clays in aggregates used to produce cement concrete, bituminous materials, and chip seals : technical report.

    Science.gov (United States)

    2013-07-01

    The clay contamination of coarse and fine aggregates and its effects on pavement performance of portland cement concrete, bituminous mixes and chip seals is a major concern for Texas Department of Transportation. We proposed (i) to determine what typ...

  11. Bituminous solidification, disposal, transport and burial of spent ion-exchange resins. Part of a coordinated programme on treatment of spent ion exchange resins

    International Nuclear Information System (INIS)

    Mozes, G.; Kristof, M.

    1983-07-01

    The project dealing with the incorporation of spent ion-exchange resins into bitumen was performed within the Agency coordinated research programme on treatment of spent ion-exchange resins. Physical and chemical properties of commercial ion-exchange resins, bitumens and bituminized resins were studied. It was shown that bitumen with low oil content and with a softening point of 60-70 deg. C are applicable for the incorporation of resins. The final waste form is allowed to contain maximum 50% resin. The comprehensive study of the biological resistance of B-30 bitumen was performed. That showed that any bacteriological attack can be regarded as generally insignificant. A continuously operating technology was realized on a semi-plant scale. The best operating conditions of this technology were determined. On the basis of the experience gained from the experiments a design of the bituminization plant of 50m 3 dry resin/year treatment capacity was proposed

  12. Cold bituminous mixes

    OpenAIRE

    Delak, Boštjan

    2012-01-01

    Asphalt mix (short also asphalt) can be obtained from nature (natural asphalt) or produced technically (artificial asphalt), i. e. as a mix of bituminous binder, stone grain, and other additives that improve the asphalt properties. The beginnings of the use of asphalt can be traced from 6,000 to 4,000 BC since people back then knew some materials that contained bitumen as a binder. A more frequent use of the natural asphalt, however, starts around 3,000 BC. Different peoples used it primar...

  13. Aqueous radioactive waste bituminization

    International Nuclear Information System (INIS)

    Williamson, A.S.

    1980-08-01

    The bituminzation of decontamination and ion exchange resin stripping wastes with four grades of asphalt was investigated to determine the effects of asphalt type on the properties of the final products. All waste forms deformed readily under light loads indicating they would flow if not restrained. It was observed in all cases that product leaching rates increased as the hardness of the asphalt used to treat the waste increased. If bituminization is adopted for any Ontario Hydro aqueous radioactive wastes they should be treated with soft asphalt to obtain optimum leaching resistance and mechanical stability during interim storage should be provided by a corrosion resistant container

  14. Long-term properties of bituminized waste products

    International Nuclear Information System (INIS)

    Snellman, M.; Valkiainen, M.

    1985-10-01

    This study is a survey of the factors of importance for long term behaviour of bituminized ion exchange resins. Phenomena occurring in bituminized waste products affected by the treatment, storage and disposal are identified. Test methods have been developed for characterizing product properties, which are important for the long-term behaviour. The long-term properties of bituminized ion-exchange resins are studied in a repository environment with access of water equilibrated with concrete. In these circumstances the most important properties are ralated to the interactions of bituminized waste with the surrounding barriers. The most important phenomena are water uptake due to rehydration of the resins and subsequent swelling of the product. (author)

  15. Long-term properties of bituminized waste products

    International Nuclear Information System (INIS)

    Snellman, M.; Valkiainen, M.

    1985-10-01

    This study is a survey of the factors of importance for the long term behaviour of bituminized ion exchange resins. Phenomena occurring in bituminized waste products affected by the treatment, storage and disposal are identified. Test methods have been developed for characterizing product properties, which are important for the long-term behaviour. The long-term properties of bituminized ion-exchange resins are studied in a repository environment with access of water equilibrated with concrete. In these circumstances the most important properties are related to the interactions of bituminized waste with the surrounding barriers. The most important phenomena are water uptake due to rehydration of the resins and subsequent swelling of the product

  16. Biocompatible implant surface treatments

    Directory of Open Access Journals (Sweden)

    Bikash Pattanaik

    2012-01-01

    Limitation of this study is that we tried to give a broader overview related to implant surface treatments. It does not give any conclusion regarding the best biocompatible implant surface treatment investigated till date. Unfortunately, the eventually selected studies were too heterogeneous for inference of data.

  17. Behaviour of bituminized radioactive wastes under irradiation

    International Nuclear Information System (INIS)

    Camaro, S.; Gilardi, T.; Vistoli, P.P.

    2000-01-01

    Studies are carried out by the CEA in order to predict the behaviour of bituminized radioactive wastes under self irradiation. Bitumen radiolysis produces gas (mainly H 2 ) which diffuses in the organic matrix. If the hydrogen yield is higher than the diffusion flux through the free surface, hydrogen concentration increases and exceeds its solubility in bitumen. Beyond saturation, bubbles are formed and gas is also evacuated by bubbles drift. The aim of these studies is to evaluate the evacuation capacity of radiolytic gas produced in function of initial bituminized wasteform characteristics. A model was developed to achieve this purpose, by calculating the evolution of bubbles population considering all elementary mechanisms of gas evacuation. (authors)

  18. Nonlinearity of bituminous mixtures

    Science.gov (United States)

    Mangiafico, S.; Babadopulos, L. F. A. L.; Sauzéat, C.; Di Benedetto, H.

    2018-02-01

    This paper presents an experimental characterization of the strain dependency of the complex modulus of bituminous mixtures for strain amplitude levels lower than about 110 μm/m. A series of strain amplitude sweep tests are performed at different temperatures (8, 10, 12 and 14°C) and frequencies (0.3, 1, 3 and 10 Hz), during which complex modulus is monitored. For each combination of temperature and frequency, four maximum strain amplitudes are targeted (50, 75, 100 and 110 μm/m). For each of them, two series of 50 loading cycles are applied, respectively at decreasing and increasing strain amplitudes. Before each decreasing strain sweep and after each increasing strain sweep, 5 cycles are performed at constant maximum targeted strain amplitude. Experimental results show that the behavior of the studied material is strain dependent. The norm of the complex modulus decreases and phase angle increases with strain amplitude. Results are presented in Black and Cole-Cole plots, where characteristic directions of nonlinearity can be identified. Both the effects of nonlinearity in terms of the complex modulus variation and of the direction of nonlinearity in Black space seem to validate the time-temperature superposition principle with the same shift factors as for linear viscoelasticity. The comparison between results obtained during increasing and decreasing strain sweeps suggests the existence of another phenomenon occurring during cyclic loading, which appears to systematically induce a decrease of the norm of the complex modulus and an increase of the phase angle, regardless of the type of the strain sweep (increasing or decreasing).

  19. Effect of transesterification degree and post-treatment on the in-service performance of NCO-functionalized vegetable oil bituminous products

    OpenAIRE

    Cuadri Vega, Antonio Abad; García Morales, Moisés; Navarro Domínguez, Francisco Javier; Partal López, Pedro

    2014-01-01

    The bitumen modification through polyurethane prepolymers presents significant benefits for the manufacture of bituminous products for the paving industry. In this sense, this work explores the use, as bitumen modifier, of a novel reactive prepolymer synthesized by reaction of 4,4´,diphenylmethane diisocyanate (MDI) and a vegetable oil-based polyol, castor oil (CO), previously transesterified with pentaerythritol. On the one hand, thermal analysis on transesterified CO revealed a highly stabl...

  20. Bituminization of liquid radioactive waste. Part 3

    International Nuclear Information System (INIS)

    G'oshev, G.S.; Gradev, G.D.; Stefanova, I.G.; Milusheva, A.G.; Guteva, E.S.; Stefanov, G.I.

    1991-01-01

    The elaborated technology for bituminization of liquid radioactive wastes (salt concentrates) is characterized by the fact that the bituminization process takes place in two stages: concentration of the liquid residue and evaporation of the water with simultaneous homogeneous incorporation of the salts in the melted bitumen. An experimental installation for bituminization of salt concentrates was designed on the basis of this technology. The experience accumulated during the design and construction of the installation for bituminization of salt concentrates could be used for designing and constructing an industrial installation for bituminization of the liquid residue of the nuclear power plants. 2 tabs., 3 figs., 3 refs

  1. Comparative study of test methods for bituminized and other low- and medium-level solidified waste materials

    International Nuclear Information System (INIS)

    Brodersen, K.; Mose Pedersen, B.; Vinther, A.

    1983-12-01

    Various aspects of the behaviour of bituminized or cemented simulated low- or medium-level radioactive waste in contact with water or salt solutions have been investigated. The solubility (approximately 0.5%) and the diffusion coefficient (approximately 5.10 -8 cm 2 /sec) determining transort of water in pure bitumen have been measured for Mexphalte 40/50 at room temperature. A weighing method has been used to study water uptake and swelling of bituminized sodium nitrate, sodium sulphate or cation-exchange resin. The swelling of samples in contact with water was in some cases very pronounced. In strong salt solutions the tendency to swell is much less. The particle size of the embedded waste material is an important parameter. Thermal pre-treatment of cation-exchange resin before bituminization does not seem to improve the quality of the final product. The interaction between bituminized-exchange resin and concrete barrier materials has been studied. Microbial degradation of bitumen and bituminized waste under aerobic conditions has been investigated. It is probably of minor importance as far as leaching is concerned. A method for measuring leaching from a plane surface of cemented waste has been developed. The method avoids the problem of cracks between the sample and the container. Leaching from cemented sodium nitrate or sulphate was investigated. Absorption of CO 2 from the atmosphere was found to have only minor effect on Cs- and Na-leaching but gave a pronounced decrease in Ca-leaching. The use of silica-fume as an additive to cemented sodium nitrate decreased the leach rate by a factor 4. (author)

  2. Pretreatment of bituminous coal for hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Hupfer, H.

    1943-03-29

    Bituminous coal became plastic at certain temperature ranges and swelled, causing plugging of preheater tubes. With few exceptions, this problem was encountered only when hydrogenating bituminous coal. This swelling often appeared in the coking of coals, and for the majority of the cases it was found that efforts to reduce the baking ability of bituminous coal also reduced the swelling of coal paste in the preheater tubes. Three methods of pretreatment to reduce swelling were preheating, oxidation (anoxidation), and sulfur treatment. The preheating by hot nitrogen at 250 atm for 3 hours showed no improvement in swelling characteristics, but produced a greater asphalt content and a lower amount of gasification. Absorption of oxygen was shown to increase the viscosity of the coal paste, while preheating in a vacuum showed no effects. Oxidation (anoxidation) increased the splitting and gasification and gave higher asphalt content. The baking ability of Saar coal could be destroyed by addition of 2.5% sulfur and heating for 1/sup 1///sub 2/ hours at 110/sup 0/C, in a stream of H/sub 2/S. The volatile content dropped significantly when the same coal was heated to 200/sup 0/ to 250/sup 0/C. When neutralized Saar coal was dried under a stream of H/sub 2/S, only slight deterioration of the yield was noted with equal degree of gasification. It was concluded that a more or less distinct improvement would be observed from the absorption of sulfur, but that residue processing would have to be altered to account for the sulfur content.

  3. Rutting performance of cold bituminous emulsion mixtures

    Science.gov (United States)

    Arshad, Ahmad Kamil; Ali, Noor Azilatom; Shaffie, Ekarizan; Hashim, Wardati; Rahman, Zanariah Abd

    2017-10-01

    Cold Bituminous Emulsion Mixture (CBEM) is an environmentally friendly alternative to hot mix asphalt (HMA) for road surfacing, due to its low energy requirements. However, CBEM has generally been perceived to be less superior in performance, compared to HMA. This paper details a laboratory study on the rutting performance of CBEM. The main objective of this study is to determine the Marshall properties of CBEM and to evaluate the rutting performance. The effect of cement in CBEM was also evaluated in this study. The specimens were prepared using Marshall Mix Design Method and rutting performance was evaluated using the Asphalt Pavement Analyzer (APA). Marshall Properties were analysed to confirm compliance with the PWD Malaysia's specification requirements. The rutting performance for specimens with cement was also found to perform better than specimens without cement. It can be concluded that Cold Bituminous Emulsion Mixtures (CBEM) with cement is a viable alternative to Hot Mix Asphalt (HMA) as their Marshall Properties and performance obtained from this study meets the requirements of the specifications. It is recommended that further study be conducted on CBEM for other performance criteria such as moisture susceptibility and fatigue.

  4. Technical and economic assessment of process of treatment of coated bituminous sludge by combustion/vitrification (report PNGMDR 2013-2015)

    International Nuclear Information System (INIS)

    2015-01-01

    This note reports the assessment of a processing by combustion/vitrification of about 60.000 parcels of coated bituminous sludge belonging to intermediate-level long-lived and low-level long-lived category, and warehoused on the Marcoule CEA site. This assessment identifies the front-end cost of an exploratory R and D which would be required to undo technological locks, the cost of design, realisation and exploitation of the associated installation, and the negative features dues to the lack of technological maturity and to the management of environmental risks and impacts in comparison with the reference industrial solution (geological storage). As a conclusion, the authors state that the process is still not technically feasible

  5. Building 107 for surface treatment

    CERN Multimedia

    Brice, Maximilien

    2018-01-01

    A brand new state-of-the-art building hosting laboratories for the surface treatment of vacuum equipment and workshops for the manufacturing and treatment of printed circuit boards was completed in 2017.

  6. Economy of bituminous coal hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    von Hochstetter, H.

    1944-05-11

    The influence of various factors on the production cost of (Janina) bituminous coal hydrogenation is analyzed briefly. The initial reckoning yielded a production cost of 188 marks per metric ton of gasoline and middle oils. The savings concomitant to changes of one percent in gasification, one percent in utilization of purified coal, one percent raising of space/time yield, one percent increase in throughput, one percent in coal concentration in the paste, and one percent in low temperature carbonization yield are listed. Factors affecting hydrogen consumption are listed in a table. Investigations showed the carbon-richest coal to produce a deviation in the effect of gasification upon the working costs by only 10 percent when compared with the Janina coal. Thus, the values listed were considered as guidelines for all kinds of bituminous coal. The calculations admitted the following conclusions: a maximum concentration of coal in the paste is desirable; one can assume a 2 percent reduction in the utilization with a 10 percent increase in throughput, as long as no changes in low temperature carbonization yield take place by changing the distribution in oil production; this configuration would change if the major concern were gas production instead of working costs, or if hydrogen production were the bottleneck. 1 table.

  7. Investigation and analytical results of bituminized products in drums at filing room

    International Nuclear Information System (INIS)

    Shibata, Atsuhiro; Kato, Yoshiyuki; Sano, Yuichi; Kitajima, Takafumi; Fujita, Hideto

    1999-09-01

    This report describes the results of investigation of the bituminized products in drums, liquid waste in the receiving tank V21 and the bituminized mixture in the extruder. The investigation of the products in drums showed most of the unburned products filled after 28B had abnormality, such as hardened surfaces, caves and porous brittle products. The particle sizes of the salt fixed in bituminized products depended neither on batch number nor on feed rate. It indicates the fining of the salt particle caused by the decreased feed rate did not occur. The measured concentrations of metals and anions in the bituminized products showed no abnormality. The catalytic content was not recognized in the products. The infrared absorption spectra obtained with the bituminized products show the oxidation at the incident occurred without oxygen. There was no organic phase on the surface of liquid waste in V21. Chemical analysis and thermal analysis on the precipitate in V21 showed no abnormality. Concentration of sodium nitrate/nitrite in the mixture collected from the extruder was lower than normal products. These results show no chemical activation of the bituminized products. It can be concluded that the chemical characteristics of the products had little abnormality even around the incident. (author)

  8. State of the art report on bituminized waste forms of radioactive wastes

    International Nuclear Information System (INIS)

    Kim, Tae Kook; Shon, Jong Sik; Kim, Kil Jeong; Lee, Kang Moo; Jung, In Ha

    1998-03-01

    In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs

  9. Leachability of bituminized radioactive waste. Literature survey

    International Nuclear Information System (INIS)

    Akimoto, Toshiyuki; Nakayama, Shinichi; Iida, Yoshihisa; Nagano, Tetsushi

    1999-02-01

    Bituminized radioactive waste that will be returned from COGEMA, France is planned to be disposed of in deep geologic repository in Japan. Data on leachability of radionuclides from bituminized waste are required for the performance assessment of the disposal. We made a literature survey on bitumen and bituminized radioactive waste, placing emphasis on leach tests and leach data in terms of geologic disposal. This survey revealed that reliable leach data on transuranium elements and data obtained under reducing conditions that is characteristic to deep underground are lacking. (author). 64 refs

  10. Cold weather paving requirements for bituminous concrete.

    Science.gov (United States)

    1973-01-01

    Cold weather paving specifications were developed from work by Corlew and Dickson, who used a computer solution to predict the cooling rate of bituminous concrete. Virginia had used a minimum atmospheric temperature as a criterion; however, it was ev...

  11. Development of bituminization process for radioactive wastes

    International Nuclear Information System (INIS)

    Segawa, Takeshi; Yamamoto, Masao; Miyao, Hidehiko; Mizuno, Ryukichi

    1973-01-01

    For the bituminization of radioactive wastes from a fuel reprocessing plant, the leachability, irradiation stability and burning property of bitumen products have been studied. Sodium nitrate was used for simulated evaporator concentrate, and mixed with distillation bitumen or blown bitumen; the sodium nitrate content in the mixture was 30 to 60 wt%. The distillation bitumen is superior to the blown bitumen in leachability and flash point, but inferior in the increase of volume by irradiation. Since the volume increase is not large, the distillation bitumen is satisfactory for the bituminization of the evaporator concentrate from a fuel reprocessing plant. (Mori, K.)

  12. Crumb Rubber in cold recycled bituminous mixes

    DEFF Research Database (Denmark)

    Dondi, Giulio; Tataranni, Piergiorgio; Pettinari, Matteo

    2014-01-01

    Today recycling is one of the most innovative and interesting techniques for the rehabilitation of destressed road pavements. In recent years the increased interest in this process, has led to the development of various alternative methods for the recovery and the reuse of road bituminous materials....... Cold recycling is, among the recycling techniques, certainly the most studied and developed: it allows the recovering of bituminous material from an existing pavement without the addition of heat, whilst ensuring the creation of high quality bound base layers. A wide range of materials have been tested...

  13. Firing a sub-bituminous coal in pulverized coal boilers configured for bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    N. Spitz; R. Saveliev; M. Perelman; E. Korytni; B. Chudnovsky; A. Talanker; E. Bar-Ziv [Ben-Gurion University of the Negev, Beer-Sheva (Israel)

    2008-07-15

    It is important to adapt utility boilers to sub-bituminous coals to take advantage of their environmental benefits while limiting operation risks. We discuss the performance impact that Adaro, an Indonesian sub-bituminous coal with high moisture content, has on opposite-wall and tangentially-fired utility boilers which were designed for bituminous coals. Numerical simulations were made with GLACIER, a computational-fluid-dynamic code, to depict combustion behavior. The predictions were verified with full-scale test results. For analysis of the operational parameters for firing Adaro coal in both boilers, we used EXPERT system, an on-line supervision system developed by Israel Electric Corporation. It was concluded that firing Adaro coal, compared to a typical bituminous coal, lowers NOx and SO{sub 2} emissions, lowers LOI content and improves fouling behavior but can cause load limitation which impacts flexible operation. 21 refs., 7 figs., 3 tabs.

  14. Results of exploitation of a pilot-plant installation for bituminization of radioactive sludges

    International Nuclear Information System (INIS)

    Golinski, M.; Ksiazak, Z.; Surala, J.; Dziubecki, R.

    1974-01-01

    Results are discussed of exploitation of a pilot-plant installation for bituminization of radioactive sludges of an efficiency of 25 l/h. In a time period of 20 month 120 cycles were carried out in which 60 m 3 of 2-4% sludges from treatment of low-level waste by the phosphate-ferrocyanide method were solidified. The P-60 asphalt was used for bituminization. The bituminization products contained 5-13.5% of mineral substances. Their activity was in the range 5 x 10 -4 - 5 x 10 -3 μCi/g for alpha emitters and 1.2 - 3.8 x 10 -2 μCi/g for beta emitters. (author)

  15. Noise Reduction Properties of an Experimental Bituminous Slurry with Crumb Rubber Incorporated by the Dry Process

    Directory of Open Access Journals (Sweden)

    Moisés Bueno

    2014-08-01

    Full Text Available Nowadays, cold technology for asphalt pavement in the field of road construction is considered as an alternative solution to conventional procedures from both an economic and environmental point of view. Among these techniques, bituminous slurry surfacing is obtaining an important role due to the properties of the obtained wearing course. The functional performance of this type of surfaces is directly related to its rough texture. Nevertheless, this parameter has a significant influence on the tire/road noise generation. To reduce this undesirable effect on the sound performance, new designs of elastic bituminous slurries have been developed. Within the FENIX project, this work presents the acoustical characterization of an experimental bituminous slurry with crumb rubber from wasted automobile tires incorporated by the dry process. The obtained results show that, under controlled operational parameters, the close proximity sound levels associated to the experimental slurry are considerably lower than those emitted by a conventional slurry wearing course. However, after one year of supporting traffic loads and different weather conditions, the evaluated bituminous slurry, although it conserves the original noise reduction properties in relation to the conventional one, noticeably increases the generated sound emission. Therefore, it is required to continue improving the design of experimental surfaces in order to enhance its long-term performance.

  16. Pretreatment of bituminous coal for hydrogenation (older experiments)

    Energy Technology Data Exchange (ETDEWEB)

    Hupfer, H.

    1943-03-29

    The tendency for coal paste to become plastic inside a certain temperature range, which sometimes caused plugging in the preheater tubes, was observed only in bituminous coal. This phenomenon, called swelling, was seen as parallel to the increase in volume of the coal in coking or carbonization, which had been observed with melting bituminous coal. Although the parallel did not hold for all cases, the frequent simultaneous occurrence of the two phenomena suggested the possibility that those treatments of coal which reduced its baking ability would also improve its behavior in the preheater. Unequivocal results were not obtained, but certain predictions could be made about a pretreatment of coal for hydrogenation. (1) With preheating, no influence with regard to pressure plugging was detected in Brassert coal, although Saar coal Louisenthal, preheated, produced a better asphalt content and lower gasification experimentally. (2) Change in coal due to anoxidation increased the viscosity of the coal paste, while preheating in vacuum had no effect. (3) The baking ability of Saar coal could be destroyed by a sulfur treatment, without appreciably diminishing the volatile content. In general, a distinct improvement was observed with the absorption of sulfur.

  17. Radioactive wastes bituminization by the pilot-plant equipment

    International Nuclear Information System (INIS)

    Golinsky, M.; Ferenc, M.; Ksendzak, Z.; Tikal, A.

    1978-01-01

    Operation experience of pilot-plant for bituminization of radioactive wastes by the method of hot mixing is described. The results obtained have conffirmed parameters of the process gained in laboratory conditions for asphalts D-35 and P-60. The results are stated for experiments of bituminization of still residuums obtained as a result of distillation of low and intermediate-level of activity sewage waters. Chemical composition of the still residuums and characteristics of the P-60 asphalt are given. Bituminization of crystal sodium nitrate and supersaturated solutions at 200 centigrades up to 30% contents of salt in the compound was performed. It is shown that bituminization results depend on salts composition of radioactive wastes subject to solidification. The results are described of investigations of bituminization by the method of hot mixing of still residuums of radioactive wastes containing sodium nitrates on the pilot-plant. Parameters are given of bituminization process and characteristics of compounds obtained in bituminization of still residuums in a form of concentrates. Leachind process for wastes solidificated by the method of bituminization has been investigated. Leaching rate for radionuclides incorporated into bituminization products depending on time of storage is given. Results of the spectrometric analysis of solidificated concentrates, bituminization product and gaseous products of radioactive wastes processing by the method of hot mixing are given. (I.T.) [ru

  18. Bituminization of liquid radioactive wastes. Part 1

    International Nuclear Information System (INIS)

    Gradev, G.D.; Ivanov, V.I.; Stefanova, I.G.; Milusheva, A.G.; Guteva, E.S.; Zhelyazkov, V.T.; Stefanov, G.I.; G'oshev, G.S.

    1991-01-01

    Salt-bitumen products are produced by the method of 'hot mixing' of some Bulgarian bitumens (road bitumen PB 66/99 and the hydroinsulating bitumen HB 80/25) and salts (chlorides, sulphates, borates, salt mixtures modelling the liquid waste from nuclear power plants) in different ratios to determine the optimum conditions for bituminization of liquid radioactive waste. The penetration, ductility and softening temperature were determined. The sedimentation properties and the thermal resistance of the various bitumen-salt mixtures were studied. The most suitable bitumen for technological research at the Kozloduy NPP was found to be the road bitumen PB 66/90 with softening temperature at 48 o C. The optimum amount of salts incorporated in the bitumen - about 45% - was found. No exothermal effects were observed in the bituminization process in the temperature range of up to 200 o C. The results obtained may be useful in the elaboration of a technology for bituminization of liquid radioactive wastes in the Kozloduy NPP. 4 tabs., 5 figs., 4 refs

  19. Bituminization of low- and medium-level radioactive wastes

    International Nuclear Information System (INIS)

    Lefillatre, G.

    1976-01-01

    French operations are presented concerning mainly: the bituminization of radioactive wastes produced in light water reactors; the direct bituminization of liquid effluents without concentration; the experiments carried out for 18 months on the land burial of concentrates solidified by bitumen into blocks of 100 liters. The knowledge acquired in France is exposed: in Valduc and in Saclay with facilities equipped with thin film evaporators and in Marcoule with the conditioning of trilaurylamine and tributyl-phosphate. At last the Cadarache bituminization [fr

  20. Noise Reduction Properties of an Experimental Bituminous Slurry with Crumb Rubber Incorporated by the Dry Process

    OpenAIRE

    Bueno, Moisés; Luong, Jeanne; Terán, Fernando; Viñuela, Urbano; Vázquez, Víctor; Paje, Santiago

    2014-01-01

    Nowadays, cold technology for asphalt pavement in the field of road construction is considered as an alternative solution to conventional procedures from both an economic and environmental point of view. Among these techniques, bituminous slurry surfacing is obtaining an important role due to the properties of the obtained wearing course. The functional performance of this type of surfaces is directly related to its rough texture. Nevertheless, this parameter has a significant influence on th...

  1. Optimization of the encapsulation process of bituminized radioactive wastes

    International Nuclear Information System (INIS)

    Silva, Jarine E.C.; Tello, Clédola C.O.

    2017-01-01

    The objective of this paper is to propose alternatives for the deposition of bituminized waste in metallic packages coated with a cementitious matrix for surface repository, aiming to meet the standards criteria and increasing the integrity of the metallic packaging during the planned storage time, transportation and disposal. For this purpose, tests will be carried out to evaluate cement pastes and mortar with cementitious additives, aiming at the durability and reduction of pores. Leaching tests with different thicknesses will also be carried out, where optimization of the encapsulation can meet safety, durability and economy standards for the repository, as well as practices that contribute to reduce environmental impacts and the economic burden imposed on future generations

  2. Method for surface treatment by electron beams

    International Nuclear Information System (INIS)

    Panzer, S.; Doehler, H.; Bartel, R.; Ardenne, T. von.

    1985-01-01

    The invention has been aimed at simplifying the technology and saving energy in modifying surfaces with the aid of electron beams. The described beam-object geometry allows to abandon additional heat treatments. It can be used for surface hardening

  3. Bituminization of radioactive wastes at the Nuclear Research Center Karlsruhe

    International Nuclear Information System (INIS)

    Hild, W.; Kluger, W.; Krause, H.

    1976-05-01

    A summary is given of the main operational experience gained at the Nuclear Research Center Karlsruhe in 4 years operation of the bituminization plant for evaporator concentrates from low- and medium level wastes. At the same time some of the essential results are compiled that have been obtained in the R + D activities on bituminization. (orig.) [de

  4. Response Modelling of Bitumen, Bituminous Mastic and Mortar

    NARCIS (Netherlands)

    Woldekidan, M.F.

    2011-01-01

    This research focuses on testing and modelling the viscoelastic response of bituminous binders. The main goal is to find an appropriate response model for bituminous binders. The desired model should allow implementation into numerical environments such as ABAQUS. On the basis of such numerical

  5. Simple volatility test for bituminous materials

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, J.A.

    1980-04-01

    A simple, inexpensive test measuring the volatility or fuming propensity of bituminous materials with good repeatability has been devised. The test depends on measuring the mass loss which occurs when a small sample of the material is heated in a shallow open dish on a thermostatic hotplate for a fixed time. A rectilinear inverse relation between the mass losses and the softening points of a series of pitches from one source has been found, and the test has been shown to give results which correlate well with other methods for characterizing pitch volatility. Test results obtained with a range of tar products from pitches to creosotes all showed similarly good repeatability. (4 refs.)

  6. Surface treatment of ceramic articles

    International Nuclear Information System (INIS)

    Komvopoulos, K.; Brown, I.G.; Wei, B.; Anders, S.; Anders, A.; Bhatia, C.S.

    1998-01-01

    A process is disclosed for producing an article with improved ceramic surface properties including providing an article having a ceramic surface, and placing the article onto a conductive substrate holder in a hermetic enclosure. Thereafter a low pressure ambient is provided in the hermetic enclosure. A plasma including ions of solid materials is produced the ceramic surface of the article being at least partially immersed in a macroparticle free region of the plasma. While the article is immersed in the macroparticle free region, a bias of the substrate holder is biased between a low voltage at which material from the plasma condenses on the surface of the article and a high negative voltage at which ions from the plasma are implanted into the article. 15 figs

  7. EFFECT OF SURFACE TREATMENT ON ENAMEL SURFACE ROUGHNESS

    Directory of Open Access Journals (Sweden)

    Şeyda Erşahan

    2016-01-01

    Full Text Available Purpose: To compare the effects of different methods of surface treatment on enamel roughness. Materials and Methods: Ninety human maxillary first premolars were randomly divided into three groups (n=30 according to type of enamel surface treatment: I, acid etching; II, Er:YAG laser; III, Nd:YAG laser. The surface roughness of enamel was measured with a noncontact optical profilometer. For each enamel sample, two readings were taken across the sample—before enamel surface treatment (T1 and after enamel surface treatment (T2. The roughness parameter analyzed was the average roughness (Ra. Statistical analysis was performed using a Paired sample t test and the post-hoc Mann- Whitney U test, with the significance level set at 0.05. Results: The highest Ra (average roughness values were observed for Group II, with a significant difference with Groups I and III (P<0.001. Ra values for the acid etching group (Group I were significantly lower than other groups (P<0.001. Conclusion: Surface treatment of enamel with Er:YAG laser and Nd:YAG laser results in significantly higher Ra than acid-etching. Both Er:YAG laser or Nd:YAG laser can be recommended as viable treatment alternatives to acid etching.

  8. Surface treatments for improved performance and properties

    International Nuclear Information System (INIS)

    Burke, J.J.; Weiss, V.

    1982-01-01

    This book considers the characteristics, structures, and properties of surfaces. Divides the subject into the physical and chemical characteristics of metallic and nonmetallic surfaces, emerging surface modification techniques, surface structure and mechanical properties, and relationships between properties and processing for nonmetallic materials. Explores various methods of surface modification that can produce improved materials properties. Discusses such wide-ranging topics as the characterization of surfaces, reaction kinetics, the chemistry of gaseous hydrogen embrittlement, the effect of surface modification on corrosion, protection against high-temperature corrosion of surfaces, the effect of high temperatures developed during plating on the microstructure and microhardness of steel, near-surface modifications that will improve the crack-tolerant behavior of high-strength alloys, fretting corrosion and fretting fatigue, surface treatments for enhanced bonding between inorganic surfaces and polymers, and the relationships between surface structure, ceramic processing, and mechanical properties. Recommended for workers and researchers in materials science, surface science, and mechanical engineering. Constitutes the proceedings of the Twenty-sixth Sagamore Army Materials Research Conference (entitled ''Surface Treatments for Improved Performance and Properties'') held in New York in 1979

  9. [Determination of aromatic polycyclic hydrocarbons during the installation of bituminous acoustic insulation panels].

    Science.gov (United States)

    Gianello, G; Marrubini, G; La Bua, R; Laurini, C; Bergamaschi, A

    2006-01-01

    Two kinds of bituminous European and Asiatic origin panels, used as acoustic insulators in the production of electrical household appliances have been analysed. The tests, made at 180 degrees C, operation temperature during the assembly phases, have been executed by sampling the smokes released during the thermal treatment, subsequently analysed by GC-MS. The results showed a marked difference between the two samples in the amount of the issued compounds, essentially constituted by alkyl-aromatic hydrocarbons, IPA and Alkyl-IPA.

  10. Surface Water Treatment Workshop Manual.

    Science.gov (United States)

    Ontario Ministry of the Environment, Toronto.

    This manual was developed for use at workshops designed to increase the knowledge of experienced water treatment plant operators. Each of the fourteen lessons in this document has clearly stated behavioral objectives to tell the trainee what he should know or do after completing that topic. Areas covered in this manual include: basic water…

  11. Processing of bituminous coal tar at high temperature with bituminous coal additive

    Energy Technology Data Exchange (ETDEWEB)

    von Hartmann, G.B.; Hupfer, H.; Leonhardt, P.

    1943-05-10

    In short tests, results of the effects of a bituminous coal addition to the processing of tar and pitch were obtainable. Coal used was that from the Heinitz Mines (Upper Silesian), saturated with 1--1.2% iron sulphate. On a mixture of bituminous coal tar residue and tar oil, with a relatively low level of solids and asphalt, a substitution was made for the addition of 2% alkalized iron-grude-catalyst with 20% coal. The same yield was reached using a straight-run procedure. The coal gave somewhat more gasification and additional asphalt in the sludge without increasing the solids content correspondingly. In spite of this, the carbonization results were somewhat improved, which led one to conclude that the coal addition fostered the decomposition of the tar asphalt, and, that the asphalt from the coal could be better carbonized than that out of the tar. One found, also, that the tar mixture with coal additive permitted trouble-free hydrogenation to gasoline and middle oil. Still another short test met with success. A bituminous coal tar pitch containing 24% benzene solids and 36% asphalt, which could not be processed with iron catalyst or even molybdenum-grude, was hydrogenated to gasoline and middle oil with a usable yield of .25 by a 20--25% addition of coal. Here too, the carbonization results were good. The addition of coal had no notable influence on the properties of the resulting oils. The document included test procedures. 11 tables.

  12. Bituminization of radioactive wastes: safety problems and application fields

    International Nuclear Information System (INIS)

    Lefillatre, G.; Leconnetable, J.

    1975-01-01

    The bituminization of low and medium radioactive wastes has many advantages: volume and weight reduction; homogeneity of the solid obtained; good resistance to leaching (biological resistance to microorganisms, resistance to radiations); very favorable characteristics for transport and storage. The latest bituminization facility put into service at the CEA is that of the Saclay Center. The bituminization unit is located after a primary evaporator having a distillation capacity of 2m 3 /h. It enables the coating of effluents at the rate of 60l/h [fr

  13. Surface treatments for aluminium alloys

    Science.gov (United States)

    Ardelean, M.; Lascău, S.; Ardelean, E.; Josan, A.

    2018-01-01

    Typically, in contact with the atmosphere, the aluminium surface is covered with an aluminium oxide layer, with a thickness of less than 1-2μm. Due to its low thickness, high porosity and low mechanical strength, this layer does not protect the metal from corrosion. Anodizing for protective and decorative purposes is the most common method of superficial oxidation processes and is carried out through anodic oxidation. The oxide films, resulted from anodizing, are porous, have a thickness of 20-50μm, and are heat-resistant, stable to water vapour and other corrosion agents. Hard anodizing complies with the same obtains principles as well as decorative and protective anodization. The difference is in that hard anodizing is achieved at low temperatures and high intensity of electric current. In the paper are presented the results of decorative and hard anodization for specimens made from several aluminium alloys in terms of the appearance of the specimens and of the thickness of the anodized.

  14. Surface Water Treatment Rules State Implementation Guidance

    Science.gov (United States)

    These documents provide guidance to states, tribes and U.S. EPA Regions exercising primary enforcement responsibility under the Safe Drinking Water Act. The documents contain EPA’s recommendations for implementation of the Surface Water Treatment Rules.

  15. Observation of gliding arc surface treatment

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Zhu, Jiajian; Ehn, A.

    2015-01-01

    . Water contact angle measurements indicate that the treatment uniformity improves significantly when the AC gliding arc is tilted to the polymer surface. Thickness reduction of the gas boundary layer, explaining the improvement of surface treatment, by the ultrasonic irradiation was directly observed...... surfaces. A gap was observed between the polymer surface and the luminous region of the plasma column, indicating the existence of a gas boundary layer. The thickness of the gas boundary layer is smaller at higher gas flow-rates or with ultrasonic irradiation to the AC gliding arc and the polymer surface......An alternating current (AC) gliding arc can be conveniently operated at atmospheric pressure and efficiently elongated into the ambient air by an air flow and thus is useful for surface modification. A high speed camera was used to capture dynamics of the AC gliding arc in the presence of polymer...

  16. Tooth surface treatment strategies for adhesive cementation

    OpenAIRE

    Rohr, Nadja; Fischer, Jens

    2017-01-01

    PURPOSE The aim of this study was to evaluate the effect of tooth surface pre-treatment steps on shear bond strength, which is essential for understanding the adhesive cementation process. MATERIALS AND METHODS Shear bond strengths of different cements with various tooth surface treatments (none, etching, priming, or etching and priming) on enamel and dentin of human teeth were measured using the Swiss shear test design. Three adhesives (Permaflo DC, Panavia F 2.0, and Panavia V5) and one sel...

  17. Effect of antistripping additives on the compaction of bituminous concrete.

    Science.gov (United States)

    1981-01-01

    The objective of this investigation was to determine the effect of antistripping additives on the compaction of bituminous concrete. To do this, the densities obtained on test sections with and without additive were compared. Comparisons of nuclear d...

  18. Design of bituminous mixes with high skid resistance.

    Science.gov (United States)

    1979-01-01

    Certain highway locations need exceptionally high skid resistance because of the alignment, geometry, and drainage of the roadway and the complex turning maneuvers required. Several beam specimens made of bituminous mixes incorporating unconventional...

  19. Bituminous and asphaltic membranes for radioactive waste repositories on land

    International Nuclear Information System (INIS)

    1988-03-01

    The aim of the study has been to identify, within generic designs for waste facilities, areas where bituminous materials might be incorporated as a barrier. The report is presented in three sections: Part I - The properties of bitumen are described, with particular reference to the long-term behaviour of the material. The durability of bitumen is discussed, including aspects such as ageing, microbial degradation, chemical resistance and radiation resistance. Part II -The use of bituminous materials in hydraulic engineering is outlined. Much of this section of the report concentrates on the use of bituminous materials in embankment dams and reservoir construction. A review of material technology and construction techniques is presented and a detailed assessment made of the performance of the materials in service. Part III - Generic trench type radioactive waste repository designs incorporating bituminous materials are presented. Material and construction specifications for the designs are detailed, and a performance assessment presented. (author)

  20. A NEW APPROACH AT SURFACE ENGINEERING; DUPLEX SURFACE TREATMENT

    Directory of Open Access Journals (Sweden)

    Akgün ALSARAN

    2003-01-01

    Full Text Available Duplex surface process was developed to deposite thin ceramic film coating on commonly manufacturing used low alloy steels. Low alloy steel having low strength by this process was first plasma nitrided with purpose enhancing load bearing capacity and then deposited with such ceramic coating. In this study, the duplex surface treatment was deal with main lines and informed about advantage and disadvantage.

  1. INVESTIGATION ON UTILITY OF PLASTIC WASTE AS AN ADDITIVE FOR BITUMINOUS CONCRETE USING WET PROCESS OF MIXING

    Directory of Open Access Journals (Sweden)

    Anurag Virendra Tiwari

    2017-12-01

    Full Text Available Purpose. Plastic waste has become a major environmental issue of concern due to its exponential growth due to rapid urbanization. The paper investigates utility of plastic waste as an additive for bituminous concrete using wet process of mixing. Methodology. The methodology for the present paper has been designed with complex research consisting of Marshall mix design of the bituminous mix added with plastic waste for modifying bitumen using wet process of mixing, performing the tests on the samples and analyzing the results in the form of table and figures. In the present paper LDPE and HDPE type of plastic waste are used to modify the bitumen. Finding. The results show that addition of 6 percent of bitumen improves the Marshall properties of the mix. Use of plastic to modify the bitumen not only makes the road surface more durable but also it is an eco-friendly way of proper disposal of plastic waste. Originality. The processes used for mixing the plastic waste to the bitumen are dry process and wet process. Dry process of mixing the plastic waste to the bituminous mix is most common and lot of study is carried out on its application. In the present paper wet process of mixing has not yet been studied much. Practical Value. The practical application of utilizing the plastic waste to modify bitumen in the bituminous mix improves the stability values resulting in the more durable road surface. Also the method ensures the proper disposal of plastic waste in eco-friendly way.

  2. Adhesion Promoters in Bituminous Road Materials: A Review

    Directory of Open Access Journals (Sweden)

    Cesare Oliviero Rossi

    2017-05-01

    Full Text Available This review focuses on certain classes of organic compounds known variously in the specific literature of asphalt as adhesion promoters, antistripping agents, wetting agents, antistrips, or adhesion agents. These kinds of organic additives are currently formulated to enhance the bitumen coating of mineral aggregates and improve the workability of asphalt mixtures. In this review, the term “adhesion promoters” includes both synthetic organic compounds as well as those extracted from natural resources, mixed in trace amounts to bitumen. Their main role is to alter the interfacial energy, so that the presence of water, even in trace, does not weaken the bitumen-aggregate bond and tends to favor adhesion. The report also considers the chemical functionalities that play a predominant role in bonding, as well as the effects of surface modification of the aggregate due to the presence of adhesion promoters in pre-blended bituminous mixtures. Although bitumen is widely used in road pavement construction and the discussion is mainly addressed to the improvement of adhesion in road materials, adhesion and wetting properties can also represent a general issue in various bitumen-based industrial products.

  3. Gasification of high ash, high ash fusion temperature bituminous coals

    Science.gov (United States)

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

    2015-11-13

    This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

  4. Plasma assisted surface treatments of biomaterials.

    Science.gov (United States)

    Minati, L; Migliaresi, C; Lunelli, L; Viero, G; Dalla Serra, M; Speranza, G

    2017-10-01

    The biocompatibility of an implant depends upon the material it is composed of, in addition to the prosthetic device's morphology, mechanical and surface properties. Properties as porosity and pore size should allow, when required, cells penetration and proliferation. Stiffness and strength, that depend on the bulk characteristics of the material, should match the mechanical requirements of the prosthetic applications. Surface properties should allow integration in the surrounding tissues by activating proper communication pathways with the surrounding cells. Bulk and surface properties are not interconnected, and for instance a bone prosthesis could possess the necessary stiffness and strength for the application omitting out prerequisite surface properties essential for the osteointegration. In this case, surface treatment is mandatory and can be accomplished using various techniques such as applying coatings to the prosthesis, ion beams, chemical grafting or modification, low temperature plasma, or a combination of the aforementioned. Low temperature plasma-based techniques have gained increasing consensus for the surface modification of biomaterials for being effective and competitive compared to other ways to introduce surface functionalities. In this paper we review plasma processing techniques and describe potentialities and applications of plasma to tailor the interface of biomaterials. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Testing of bituminized ion-exchange resin waste products from a nuclear power plant

    International Nuclear Information System (INIS)

    Muurinen, A.K.; Vuorinen, U.S.

    Testing methods are described and preliminary results presented for the bituminized waste products from TVO nuclear power plant. Radiation effects on the physical and chemical characteristics of the waste product and a pure bitumen sample were studied using an external 60 Co gamma source. Results of the postirradiation study show that the relative density decreases for both the waste products and the bitumen. Softening points rise for waste products but drop for bitumen. Breaking point of the powder resin waste product drops; in the granular resin waste product it rises on the surface and slightly decreases or does not significantly change at the bottom. For bitumen the breaking point rises

  6. Surface Treatments of Nb by Buffered Electropolishing

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Andy T. [JLAB; Rimmer, Robert A. [JLAB; Ciovati, Gianluigi [JLAB; Manus, Robert L. [JLAb; Reece, Charles E. [JLAB; Williams, J. S. [JLAB; Eozénou, F. [CEA, Gif-sur-Yvette; Jin, S. [PKU/IHIP, Beijing; Lin, L. [PKU/IHIP, Beijing; Lu, X.Y. [PKU/IHIP, Beijing; Mammosser, John D. [JLAB; Wang, E. [BNL

    2009-11-01

    Buffered electropolishing (BEP) is a Nb surface treatment technique developed at Jefferson Lab1. Experimental results obtained from flat Nb samples show2-4 that BEP can produce a surface finish much smoother than that produced by the conventional electropolishing (EP), while Nb removal rate can be as high as 4.67 μm/min. This new technique has been applied to the treatments of Nb SRF single cell cavity employing a vertical polishing system5 constructed at JLab as well as a horizontal polishing system at CEA Saclay. Preliminary results show that the accelerating gradient can reach 32 MV/m for a large grain cavity and 26.7 MV/m for a regular grain cavity. In this presentation, the latest progresses from the international collaboration between Peking University, CEA Saclay, and JLab on BEP will be summarized.

  7. Surface treatment for inducing nanotopography on titanium

    International Nuclear Information System (INIS)

    Oliveira, S.V. de; Ribeiro, A.A.; Oliveira, M.V. de

    2014-01-01

    The titanium implant surface plays extremely important role in the biological response. Therefore, the objective of this research was to study the titanium surface nanotopography modified by chemical treatment, in order to improve its bioactivity. Commercially pure titanium samples, ASTM F67 grade 2, were immersed in H 2 SO 4 /H 2 O 2 solution for 2 or 4 hours. The samples were characterized by Scanning Electron Microscopy, Scanning Confocal Optical Microscopy, X-ray Photoelectron Spectroscopy and Diffuse Reflectance Infrared Fourier Transform Spectroscopy. The results revealed nanostructured surfaces with TiO 2 layer, average roughness of 0.86 ± 0.06 μm and 1.07 ± 0.05 μm for 2 or 4 hours, respectively and nanopores with 18 ± 6.82 nm average diameter. (author)

  8. Laser welding, cutting and surface treatment

    International Nuclear Information System (INIS)

    Crafer, R.C.

    1984-01-01

    Fourteen articles cover a wide range of laser applications in welding, cutting and surface treatment. Future trends are covered as well as specific applications in shipbuilding, the manufacture of heart pacemakers, in the electronics industry, in automobile production and in the aeroengine industry. Safety with industrial lasers and the measurement of laser beam parameters are also included. One article on 'Lasers in the Nuclear Industry' is indexed separately. (U.K.)

  9. Long Term 1 Enhanced Surface Water Treatment Rule Documents

    Science.gov (United States)

    The Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) builds on the requirements of the Surface Water Treatment Rule and specifies treatment requirements to address Cryptosporidium m and other microbial contaminants in public water systems.

  10. Tooth surface treatment strategies for adhesive cementation.

    Science.gov (United States)

    Rohr, Nadja; Fischer, Jens

    2017-04-01

    The aim of this study was to evaluate the effect of tooth surface pre-treatment steps on shear bond strength, which is essential for understanding the adhesive cementation process. Shear bond strengths of different cements with various tooth surface treatments (none, etching, priming, or etching and priming) on enamel and dentin of human teeth were measured using the Swiss shear test design. Three adhesives (Permaflo DC, Panavia F 2.0, and Panavia V5) and one self-adhesive cement (Panavia SA plus) were included in this study. The interface of the cement and the tooth surface with the different pre-treatments was analyzed using SEM. pH values of the cements and primers were measured. The highest bond strength values for all cements were achieved with etching and primer on enamel (25.6 ± 5.3 - 32.3 ± 10.4 MPa). On dentin, etching and priming produced the highest bond strength values for all cements (8.6 ± 2.9 - 11.7 ± 3.5 MPa) except for Panavia V5, which achieved significantly higher bond strengths when pre-treated with primer only (15.3 ± 4.1 MPa). Shear bond strength values were correlated with the micro-retentive surface topography of enamel and the tag length on dentin except for Panavia V5, which revealed the highest bond strength with primer application only without etching, resulting in short but sturdy tags. The highest bond strength can be achieved for Panavia F 2.0, Permaflo DC, and Panavia SA plus when the tooth substrate is previously etched and the respective primer is applied. The new cement Panavia V5 displayed low technique-sensitivity and attained significantly higher adhesion of all tested cements to dentin when only primer was applied.

  11. Measurement of heat generation from simulated bituminized product

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Yoshiyuki; Yoneya, Masayuki [TRP Safety Evaluation and Analysis team, Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    1999-09-01

    The fire and explosion incident occurred at Bituminization Demonstration Facility of PNC Tokai Works on March 11, 1997. In order to ascertain the cause of incident, the investigation has been pushed forward. For the investigation, we prepared simulated bituminized product of measurement of heat generation in low temperature region less than 200degC. We used calvet Calorimeter MS80 for the heat generation measurement. Result of measurement, we were able to catch the feeble heat generation from bituminized product. The maximum calorific value that was able to detect it in isothermal measurement was approximately 1 mW/g in 160degC. It was approximately 2 mW/g in 200degC. And, as the another measurement, the measurement condition went heat rate by 0.01degC/minute, the highest temperature 190degC. As a result, the maximum generation of heat value that was able to detect it was approximately 0.5 mW/g. I changed simulated bituminized products and measured these. A difference of condition is salt particle size, salt content rate (45%, 60%), addition of the simulated precipitate. But there was not a difference in the generation of heat characteristic detected. (author)

  12. Reuse of steel slag in bituminous paving mixtures.

    Science.gov (United States)

    Sorlini, Sabrina; Sanzeni, Alex; Rondi, Luca

    2012-03-30

    This paper presents a comprehensive study to evaluate the mechanical properties and environmental suitability of electric arc furnace (EAF) steel slag in bituminous paving mixtures. A variety of tests were executed on samples of EAF slag to characterize the physical, geometrical, mechanical and chemical properties as required by UNI EN specifications, focusing additionally on the volumetric expansion associated with hydration of free CaO and MgO. Five bituminous mixtures of aggregates for flexible road pavement were designed containing up to 40% of EAF slag and were tested to determine Marshall stability and indirect tensile strength. The leaching behaviour of slag samples and bituminous mixtures was evaluated according to the UNI EN leaching test. The tested slag showed satisfactory physical and mechanical properties and a release of pollutants generally below the limits set by the Italian code. Tests on volume stability of fresh materials confirmed that a period of 2-3 months is necessary to reduce effects of oxides hydration. The results of tests performed on bituminous mixtures with EAF slag were comparable with the performance of mixtures containing natural aggregates and the leaching tests provided satisfactory results. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Calcium Oxalate: A Surface Treatment for Limestone

    Directory of Open Access Journals (Sweden)

    Tody M. Cezar

    1998-05-01

    Full Text Available This paper looks at the artificially induced surface conversion of calcium carbonate to the more durable calcium oxalate. Extensive research is being carried out on wall paintings and marble sculpture at the Opicificio delle Pietre Dure e Laboratori di Restauro in Florence, Encouraged by their work, I have researched the effectiveness of the conversion on English limestones. The treated samples have been compared to untreated samples for appearance, hardness, resistance to acid and alkali, porosity, and durability. The results have been assessed considering ease of use, effectiveness, and the appropriateness of the treatment.

  14. Method for treatment of a surface area of steel

    NARCIS (Netherlands)

    Bhowmik, S.; Aaldert, P.J.

    2009-01-01

    The invention relates to a method for treatment of a surface area of steel by polishing said surface area and performing a plasma treatment of said surface area wherein the plasma treatment is performed at at least atmospheric conditions and wherein the plasma treatment is carried out at a power of

  15. Review and environmental impact assessment of green technologies for base courses in bituminous pavements

    International Nuclear Information System (INIS)

    Anthonissen, Joke; Van den bergh, Wim; Braet, Johan

    2016-01-01

    This paper provides a critical review of different approaches applied in the Belgian asphalt sector in order to reduce the environmental impact of bituminous road construction works. The focus is on (1) reusing reclaimed asphalt pavement, (2) reducing the asphalt production temperature, and (3) prolonging the service life of the pavement. Environmental impact assessment of these methods is necessary to be able to compare these approaches and understand better the ability to reduce the environmental impact during the life cycle of the road pavement. Attention should be drawn to the possible shift in environmental impact between various life cycle stages, e.g., raw material production, asphalt production, or waste treatment. Life cycle assessment is necessary to adequately assess the environmental impact of these approaches over the entire service life of the bituminous pavement. The three approaches and their implementation in the road sector in Flanders (region in Belgium) are described and the main findings from life cycle assessment studies on these subjects are discussed. It was found from the review that using reclaimed asphalt pavement in new bituminous mixtures might yield significant environmental gains. The environmental impact of the application of warm mix asphalt technologies, on the other hand, depends on the technique used. - Highlights: • Recycling, lower production temperature and durability of asphalt are investigated. • The use of RAP in new asphalt mixtures yields significant environmental advantages. • It would be beneficial to allow RAP in asphalt mixtures for wearing courses. • The use of particular additives might counteract the environmental gain from WMA. • The service life and the environmental data source influence the LCA results.

  16. Review and environmental impact assessment of green technologies for base courses in bituminous pavements

    Energy Technology Data Exchange (ETDEWEB)

    Anthonissen, Joke, E-mail: joke.anthonissen@uantwerpen.be [Faculty of Applied Engineering, University of Antwerp, Rodestraat 4, 2000 Antwerp (Belgium); Van den bergh, Wim, E-mail: wim.vandenbergh@uantwerpen.be [Faculty of Applied Engineering, University of Antwerp, Rodestraat 4, 2000 Antwerp (Belgium); Braet, Johan, E-mail: johan.braet@uantwerpen.be [Department Engineering Management, Faculty of Applied Economics, University of Antwerp, Prinsstraat 13, 2000 Antwerp (Belgium)

    2016-09-15

    This paper provides a critical review of different approaches applied in the Belgian asphalt sector in order to reduce the environmental impact of bituminous road construction works. The focus is on (1) reusing reclaimed asphalt pavement, (2) reducing the asphalt production temperature, and (3) prolonging the service life of the pavement. Environmental impact assessment of these methods is necessary to be able to compare these approaches and understand better the ability to reduce the environmental impact during the life cycle of the road pavement. Attention should be drawn to the possible shift in environmental impact between various life cycle stages, e.g., raw material production, asphalt production, or waste treatment. Life cycle assessment is necessary to adequately assess the environmental impact of these approaches over the entire service life of the bituminous pavement. The three approaches and their implementation in the road sector in Flanders (region in Belgium) are described and the main findings from life cycle assessment studies on these subjects are discussed. It was found from the review that using reclaimed asphalt pavement in new bituminous mixtures might yield significant environmental gains. The environmental impact of the application of warm mix asphalt technologies, on the other hand, depends on the technique used. - Highlights: • Recycling, lower production temperature and durability of asphalt are investigated. • The use of RAP in new asphalt mixtures yields significant environmental advantages. • It would be beneficial to allow RAP in asphalt mixtures for wearing courses. • The use of particular additives might counteract the environmental gain from WMA. • The service life and the environmental data source influence the LCA results.

  17. Erosion resistance comparison of alternative surface treatments

    Science.gov (United States)

    Česánek, Z.; Schubert, J.; Houdková, Š.

    2017-05-01

    Erosion is a process characterized by the particle separation and the damage of component functional surfaces. Thermal spraying technology HP/HVOF (High Pressure / High Velocity Oxygen Fuel) is commonly used for protection of component surfaces against erosive wear. Alloy as well as cermet based coatings meet the requirements for high erosion resistance. Wear resistance is in many cases the determining property of required component functioning. The application suitability of coating materials is particularly influenced by different hardness. This paper therefore presents an erosion resistance comparison of alloy and cermet based coatings. The coatings were applied on steel substrates and were subjected to the erosive test using the device for evaluation of material erosion resistance working on the principle of centrifugal erodent flow. Abrasive sand Al2O3 with grain size 212-250 μm was selected as an erosive material. For this purpose, the specimens were prepared by thermal spraying technology HP/HVOF using commercially available powders Stellite 6, NiCrBSi, Cr3C2-25%NiCr, Cr3C2-25%CoNiCrAlY, Hastelloy C-276 and experimental coating TiMoCN-29% Ni. Erosion resistance of evaluated coatings was compared with erosive resistance of 1.4923 high alloyed steel without nitridation and in nitrided state and further with surface treatment using technology PVD. According to the evaluation, the resulting erosive resistance depends not only on the selected erodent and surface protection, but also on the erodent impact angle.

  18. Potential of water-washing of rape straw on thermal properties and interactions during co-combustion with bituminous coal.

    Science.gov (United States)

    Ma, Qiulin; Han, Lujia; Huang, Guangqun

    2017-06-01

    The aim of this work was to study the thermal properties and interactions during co-combustion of rape straw (RS) before and after water-washing with bituminous coal. A series of experiments was conducted to investigate the properties and interactions during co-combustion of RS with bituminous coal (at 10, 20, 40 and 60% RS). The feasibility and potential of water-washing as an RS pre-treatment was also explored. Reactivity and the amount of heat released followed a quadratic trend, while changes to the degree of interactions between the fuels conformed to a cosine curve. Water-washing increased the ignition and burn-out temperatures and slightly decreased reactivity. Demineralization negatively affected the previously synergistic co-firing relationship, nevertheless, the amount of heat released increased by 10.28% and the average activation energy (146kJ/mol) was lower than that of the unwashed blend (186kJ/mol). Overall, water-washing of RS could prove a useful pre-treatment before co-combustion with bituminous coal. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Numerical simulation of electromagnetic surface treatment

    Science.gov (United States)

    Sonde, Emmanuel; Chaise, Thibaut; Nelias, Daniel; Robin, Vincent

    2018-01-01

    Surface treatment methods, such as shot peening or laser shock peening, are generally used to introduce superficial compressive residual stresses in mechanical parts. These processes are carried out during the manufacturing steps or for the purpose of repairing. The compressive residual stresses prevent the initiation and growth of cracks and thus improve the fatigue life of mechanical components. Electromagnetic pulse peening (EMP) is an innovative process that could be used to introduce compressive residual stresses in conductive materials. It acts by generating a high transient electromagnetic field near the working surface. In this paper, the EMP process is presented and a sequentially coupled electromagnetic and mechanical model is developed for its simulation. This 2D axisymmetric model is set up with the commercial finite element software SYSWELD. After description and validation, the numerical model is used to simulate a case of introducing residual stresses of compression in a nickel-based alloy 690 thick sample, by the means of electromagnetic pulses. The results are presented in terms of effective plastic strain and residual mean stress. The influence of the process parameters, such as current intensity and frequency, on the results is analyzed. Finally, the predictability of the process is shown by several correlation studies.

  20. Properties of bituminization product from Olkiluoto power plant

    International Nuclear Information System (INIS)

    Valkiainen, M.; Vuorinen, U.

    1985-09-01

    In Finland, disposal into repositories excavated into bedrock on the present power plant sites is considered to be the most feasible alternative for the low- and intermediate level wastes. The Nuclear Waste Commission of the Finnish power companies has sponsored mainly experimental research work on long-term properties of bituminized ion exchange resin performed in the Reactor Laboratory of the Technical Research Centre of Finland since 1981. This report presents results on follow-up measurements of the leach tests started in 1981 and results on new leach tests with cement equilibrated water. Swelling of the bituminization product caused by water uptake is considered important. Both unrestricted and restricted swelling measurements were performed and are reported here. In addition to leaching and swelling also radiolytic gas generation and pH-changes of the leachant are discussed

  1. Pulp and paper plant wastes valorisation in bituminous mixes.

    Science.gov (United States)

    Modolo, R; Benta, A; Ferreira, V M; Machado, L M

    2010-04-01

    Nowadays, the increasing amount of wastes is a concerning reality and the environmental aspects has become a major priority. Following this worry, the purpose of this experimental study was to investigate the possibility of using pulp and paper inorganic wastes, named dregs and grits, in bituminous mixtures as aggregate replacement to reduce environmental effects of these wastes disposal. First, the wastes were chemically and physically characterized and also tested primarily taking into account the requirements for aggregates in bituminous mixtures. Then, formulations were prepared replacing aggregates with wastes in different amounts. The mechanical properties of these mixtures containing wastes were compared with reference samples based on standard methods. According to the results it was possible to verify that grits had a good performance and it might be directly tested industrially as an aggregate in road construction. On the other hand, dregs need to be treated before incorporation to guarantee stable mixes in terms of water sensitivity. Copyright 2009 Elsevier Ltd. All rights reserved.

  2. Solidification of radioactive wastes by bituminization technology. II

    International Nuclear Information System (INIS)

    Stuchlik, S.; Brzobohaty, J.

    1985-01-01

    The bituminization line consists of a rotor film evaporator, a condenser, reserve tanks of bitumen emulsion and model concentrates, a roller train, a vapour concentrate tank, a control console, a bitumen emulsion pump, a model concentrates pump, and a tank for model concentrate preparation. Anion-active emulsion Silembit S-60 produced by Paramo Pardubice was chosen as the bitumen emulsion. A block diagram is given of the experimental bituminization line and its processing is described of model nonactive concentrates whose composition corresponds to that of actual wastes from the V-1 nuclear power plant. Successful tests of the line showed that it could be used for the disposal of radioactive wastes. (E.S.)

  3. Comparison of the performances of several modified bituminous mix formulas

    Science.gov (United States)

    Saoula, Samia; Haddadi, Smail; Mokhtar, Khedidja Ait

    2012-09-01

    The mechanical behaviour of several formulas of bituminous concrete containing polymer (HDPE), polymer-bitumens (EVA) and waste of sole of shoes (containing copolymer butadiene-styrene-SBR noted DSBR and ethylene and vinyl acetate-EVA noted DEVA) were studied. The aim of this work is to improvement of the poor mechanicals performances of a bituminous concrete formula (0/14) which isn't conforming to the Algerian standards. Also, the mechanical tests showed that the permanent deformations and the indirect tensile strength at the temperatures of service resistances are improved. At high-temperature service, formulas of asphalt bitumen-EVA most resistant against the average temperature in service, it mixes made with waste are best resistant. All the formulas have a good behaviour with water.

  4. Nigerian bituminous coal as a fuel-coal. | OGUGBUAJA | Global ...

    African Journals Online (AJOL)

    Nigerian bituminous coal as a fuel-coal. V O OGUGBUAJA, C L NDIOKWERE, G A DIMARI. http://dx.doi.org/10.4314/gjpas.v6i2.16113 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL ...

  5. Gamma radiation hazard to miners in bituminous coal mines

    International Nuclear Information System (INIS)

    Skubacz, K.

    1986-01-01

    Radiation hazard to miners working in 16 bituminous coal mines was determined by a thermoluminescence method. While the miners exposure to gamma radiation is higher than that of the general population, the yearly dose was never found to exceed 5 mSv in any investigated person. Factors contributing to the estimate of the exposure hazard and the need for individual dose monitoring in mines are discussed in more detail. 3 refs., 4 figs. (author)

  6. An experimental evaluation of coke production from bituminous coal tar

    Energy Technology Data Exchange (ETDEWEB)

    Kaloc, M.; Janik, M.; Rojak, A.

    1981-01-01

    Results of studies of laboratory coking of bituminous coal tar are presented, which verify the technical feasibility and suitability of this engineering process for coke production. Thanks to the closed-system character of the process, it is suitable for technological and hygienic reasons. The yield of pitch coke is higher by comparison with that from chamber coking; also the properties of this coke are better; it is suitable for more varied applications, including the production of large-diameter graphite electrodes.

  7. Laser surface treatment of grey cast iron for automotive applications

    NARCIS (Netherlands)

    Ocelik, V.; Tang, P.N.; de Boer, M.C.; de Oliveira, U.; de Hosson, J.T.M.; DeHosson, JTM; Brebbia, CA; Nishida, SI

    2005-01-01

    The surface of pearlitic grey cast iron was treated using a 2 kW Nd:YAG laser beam with the final aim to improve its surface properties, mainly for automotive applications. Two kinds of laser surface treatments were experimentally applied. In the laser surface hardening approach the surface of cast

  8. Catalytic Two-Stage Liquefaction (CTSL) process bench studies with bituminous coal. Final report, [October 1, 1988--December 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Johanson, E.S.; Karolkiewicz, W.F.; Lee, L.K.; Stalzer, R.H.; Smith, T.O.

    1993-03-01

    Reported herein are the details and results of Laboratory and Bench-Scale experiments using bituminous coal concluded at Hydrocarbon Research, Inc., under DOE contract during the period October 1, 1988 to December 31, 1992. The work described is primarily concerned with the application of coal cleaning methods and solids separation methods to the Catalytic Two-Stage Liquefaction (CTSL) Process. Additionally a predispersed catalyst was evaluated in a thermal/catalytic configuration, and an alternative nickel molybdenum catalyst was evaluated for the CTSL process. Three coals were evaluated in this program: Bituminous Illinois No. 6 Burning Star and Sub-bituminous Wyoming Black Thunder and New Mexico McKinley Mine seams. The results from a total of 16 bench-scale runs are reported and analyzed in detail. The tests involving the Illinois coal are reported herein, and the tests involving the Wyoming and New Mexico coals are described in Topical Report No. 1. On the laboratory scale, microautoclave tests evaluating coal, start-up oils, catalysts, thermal treatment, CO{sub 2} addition and sulfur compound effects are reported in Topical Report No. 3. Other microautoclave tests, such as tests on rejuvenated catalyst, coker liquids, and cleaned coals, are described in the Bench Run sections to which they refer. The microautoclave tests conducted for modelling the CTSL process are described in the CTSL Modelling section of Topical Report No. 3 under this contract.

  9. Biodegradation of bituminous products from processing liquid radioactive wastes

    International Nuclear Information System (INIS)

    Tibensky, L.; Krejci, F.; Hladky, E.; Halama, D.

    1988-01-01

    One of the possible ways of disturbing the stability of bituminous products from liquid radioactive waste processing, is biodegradation caused by common microorganisms. Pseudomonas bacteria and a Bacillus cereus culture were selected for experimental study of cultivation of microorganisms. Experiments with mixed cultures were also performed. Pitches, ajatin and imidazoline were used as inhibitors. The thin layer and the emulsion methods were used in assessing biological corrosion. The results of the experiments are discussed with respect to the dependence of bacterial growth on bitumen biodegradation, the effect of pH on bitumen degradation and the effect of inhibitors on bitumen biodegradation. The salts contained in bituminous products were not found to significantly affect the rate of destruction. The degree of degradation was found to mainly depend on the bitumen, its chemical composition, and on the conditions of storage. It was also found that inhibitor additions in some cases modified the properties of the matrix such that it became more liquid. The coefficient of extractibility thus increased of matrix salts. The recultivation of bacteria on a full-value medium resulted in the loss of the inhibitory effect. In some cases, the inhibitor even stimulated the growth of microorganisms. The use of inhibitors in an effort to achieve biostability of bituminous products thus did not solve the problem. (Z.M.). 2 tabs., 9 refs

  10. Influence of the carbon fiber surface microstructure on the surface chemistry generated by a thermo-chemical surface treatment

    International Nuclear Information System (INIS)

    Vautard, F.; Ozcan, S.; Paulauskas, F.; Spruiell, J.E.; Meyer, H.; Lance, M.J.

    2012-01-01

    Highlights: ► Continuous thermo-chemical surface treatment used to functionalize different types of carbon fibers. ► Surface density of functional groups directly correlated to the size of the surface microstructure. ► Preferential creation of hydroxyls and carboxylic acids confirmed regardless of the type of carbon fiber. ► Effective surface treatment regardless of the fiber surface microstructure. ► Potential alternative to electro-chemical surface treatment. - Abstract: Carbon fibers made of textile and aerospace grade polyacrylonitrile precursor fibers were surface treated by a continuous gas phase thermochemical treatment. The surface chemistry generated by the surface treatment was characterized by X-ray photoelectron spectroscopy. The surface and the average entire microstructure of the fibers were characterized by Raman spectroscopy and X-ray diffraction, respectively. Depending on the grade of the precursor, the final surface concentration of oxygen was comprised between 14% and 24%, whereas the typical commercial electrochemical surface treatments led to concentrations of around 8% with the same fibers. The final concentration of oxygen was directly correlated to the size of the crystallites which was a function of the grade of the polyacrylonitrile precursor and to the corresponding surface microstructure. The thermochemical surface treatment enabled a better control of the nature of the oxygen-containing functionalities as well. Whatever the grade of the precursor, desired hydroxyl groups and carboxylic acid functionalities were preferably generated, which is observed to be difficult with electrochemical surface treatments.

  11. Key indexes of the effectiveness of mask surface treatments

    Science.gov (United States)

    Lin, Chen-Yang; Liu, Chung-Hsuan; Lin, Kuan-Wen; Lu, Chi-Lun; Hsu, Luke; Chin, Angus; Yen, Anthony

    2015-10-01

    A proper surface treatment, such as O2 plasma, helps to improve particle removal efficiency (PRE) because of the formation of hydrogen bonding between particles, water and the mask surface after treatment. The effectiveness of surface treatments cannot be determined only by the static wettability after processes. More key indexes should be considered. In this paper, we report our findings on the relationship between surface treatments on photomasks and the resulting wettability. In addition, added defects after the treatment and the cleaning process were inspected with a 193- nm KLA inspector on 193-nm immersion and EUV photomasks, which consist of SiO2, MoSi, Cr, Ta-based absorber and Ru. Based on our work, three indexes can be built for determining the effectiveness of surface treatments. The first is to check whether the surface becomes super-hydrophilic after treatment. The second is to determine the efficiency of surface treatments on enhancing wettability. The last is to quantify the added watermark count after the surface treatment and the cleaning process. With a proper surface treatment, watermarks can be greatly eased. These three indexes can quickly determine possible effective methods for treating the surfaces of different materials.

  12. Specific provisions applicable to the production, inspection, treatment, packaging and interim storage of low and medium level bituminized wastes resulting from the reprocessing of fuels irradiated in pressurized water reactors

    International Nuclear Information System (INIS)

    1984-04-01

    The Fundamental Safety Rules applicable to certain types of nuclear installation are intended to clarify the conditions of which observance, for the type of installation concerned and for the subject that they deal with, is considered as equivalent to compliance with regulatory French technical practice. These Rules should facilitate safety analysises and the clear understanding between persons interested in matters related to nuclear safety. They in no way reduce the operator's liability and pose no obstacle to statutory provisions in force. For any installation to which a Fundamental Safety Rule applies according to the foregoing paragraph, the operator may be relieved from application of the Rule if he shows proof that the safety objectives set by the Rule are attained by other means that he proposes within the framework of statutory procedures. Furthermore, the Central Service for the Safety of Nuclear Installations reserves the right at all times to alter any Fundamental Safety Rule, as required, should it deem this necessary, while specifying the applicability conditions. This rule sets forth the specific provisions applicable to the production, inspection, treatment, packaging and interim storage of the wastes, resulting from the reprocessing of fuels irradiated in a PWR and coated in bitumen

  13. Bioinspired Surface Treatments for Improved Decontamination: Icephobic Surfaces

    Science.gov (United States)

    2017-06-26

    superhydrophobic water contact angles (>150°) that were previously reported. Heptane wetted all surfaces, producing contact angles below the measurable threshold...5 TABLES Table 1 — Contact angles ...fluorosilane to produce both texture and hydrophobic properties. [1, 2] The coating technology is reported to produce a water contact angle of greater than

  14. Ion surface treatments on organic materials

    Science.gov (United States)

    Iwaki, Masaya

    2001-04-01

    A study has been made of surface modification of various organic materials by ion bombardment or implantation to make the surface properties of high and multiple functions in RIKEN. Substrates used were polyimide (PI), polyacetylene, polytetrafluoroethylene (PTFE), polystyrene (PS), silicone rubber, various kinds of proteins and so on. Bombarded or implanted ions were inert gas elements, chemically active gaseous elements and metallic elements. Surface properties such as electrical conductivity, wettability and cell adhesion of implanted layers have been investigated. Surface characterization of implanted materials has been carried out by means of transmission electron microscopy, laser Raman spectroscopy, X-ray photoelectron spectroscopy and Rutherford backscattering spectroscopy. In this paper, studies in RIKEN are reviewed of electrical conductivity, optical absorbance, wettability and cell adhesion depending on current densities and doping elements. Applications of ion bombardment to biomedical materials are introduced using cell adhesion control. It is concluded that ion bombardment or implantation is useful to change and control surface properties of various organic materials.

  15. Surface treatment of magnetic recording heads

    Science.gov (United States)

    Komvopoulos, Kyriakos; Brown, Ian G.; Wei, Bo; Anders, Simone; Anders, Andre; Bhatia, Singh C.

    1995-01-01

    Surface modification of magnetic recording heads using plasma immersion ion implantation and deposition is disclosed. This method may be carried out using a vacuum arc deposition system with a metallic or carbon cathode. By operating a plasma gun in a long-pulse mode and biasing the substrate holder with short pulses of a high negative voltage, direct ion implantation, recoil implantation, and surface deposition are combined to modify the near-surface regions of the head or substrate in processing times which may be less than 5 min. The modified regions are atomically mixed into the substrate. This surface modification improves the surface smoothness and hardness and enhances the tribological characteristics under conditions of contact-start-stop and continuous sliding. These results are obtained while maintaining original tolerances.

  16. Public satisfaction survey of high friction surface treatment.

    Science.gov (United States)

    2017-04-01

    Missouri adults in Callaway County were surveyed to capture their satisfaction with a local high friction surface treatment on : westbound US 54. This treatment was implemented in Project J5P3012. The results are weighted proportionally to the county...

  17. Mechanical properties of hot bituminous mixes manufactured with recycled aggregate of Silestone® waste

    Directory of Open Access Journals (Sweden)

    Rubio, M. C.

    2011-03-01

    Full Text Available This article presents the results of a research project which analyzes the viability of incorporating waste material from decorative quartz solid surfacing in the manufacture of hot bituminous mixes. For this purpose, various bituminous mixes were manufactured with waste aggregate in different percentage. A set of tests were carried out that permitted the characterization of the mechanical behavior of these mixes. The results of these tests were similar to the results obtained when conventional mixes made from virgin quarry aggregate were tested. The results for moisture sensitivity as well as for wheel track rutting on mixes showed the optimal performance of this waste material even under very demanding traffic conditions. Laboratory studies showed that the use of this waste material in the manufacture of bituminous mixes is technically viable and can provide high-quality recycled aggregates at a very low cost, which can be used in the pavement of road.

    Este artículo muestra los resultados de un proyecto de investigación que tiene por objeto analizar la viabilidad de incorporación de residuos procedentes de piedra decorativa en la fabricación de mezclas bituminosas en caliente. Para ello se fabricaron mezclas con áridos reciclados de residuos procedentes de piedra decorativa en distintos porcentajes, realizando un conjunto de ensayos que posibilitaron caracterizar el comportamiento mecánico de dichas mezclas. Los resultados obtenidos fueron similares a los de las mezclas convencionales fabricadas con áridos vírgenes procedentes de cantera. Los valores de resistencia conservada ante la acción del agua y deformación en pista, pusieron de manifiesto la aptitud del residuo incluso ante las condiciones de tráfico más exigentes. Los trabajos realizados en el laboratorio indican que la utilización del residuo en la fabricación de mezclas bituminosas es técnicamente viable, pudiendo obtenerse áridos reciclados de gran calidad y

  18. Wetting of bituminized ion-exchangers under simulated repository conditions

    International Nuclear Information System (INIS)

    Aalto, H.; Valkiainen, M.

    2001-01-01

    According to the present plans the spent nuclear fuel from four Finnish nuclear power units will be transferred after interim storage to the final disposal site where it will be encapsulated and disposed of in a final repository constructed into the bedrock at a depth of 500 meters. Low and medium level waste generated at nuclear power plants will be finally disposed of in caverns constructed in the bedrock at the power plant site. The safety of the final disposal is based on a multibarrier concept and the degree of safety is estimated by using predictive models. The properties of the waste form are taken into account in the design of the repository construction. Bitumen has been chosen as an immobilisation agent for the wet wastes at Olkiluoto Power Plant, where two BWR units, TVO 1 and TVO 2, have separate bituminization facilities designed by Asea-Atom. Properties of bituminized spent ion-exchange resins from Olkiluoto power plant have been studied by VTT Chemical Technology since the late 70's. These studies have concentrated mainly on determining the long-term behaviour of the bituminization product under the repository conditions. Current interest lies on wetted product as a diffusion barrier. For this purpose a microscopic method for the visualisation of the structure of the wetted product has been developed. The equilibration of the samples in simulated concrete groundwater is currently going on at a temperature of 5-8 deg. C. Preliminary results are presented in this paper. Diffusion experiments have been planned for the further characterising of the wetted product as a release barrier for radionuclides including modelling. (author)

  19. Low NOx firing systems for bituminous coal and lignite

    International Nuclear Information System (INIS)

    Knyrim, W.; Scheffknecht, G.

    1997-01-01

    In the case of lignite fluidized boilers the denitrification down to less than 200 mg/m 3 was possible with primary measures on the firing side only. On account of the excellent results achieved with the reconstructed plants the firing systems for the new generation of brown coal fire steam generators with a capacity of 800 MW and more is designed in a similar way. For bituminous coal fire steam generators the primary measures on the firing side are nor sufficient to keep the German NO x emission limit. Therefore these units had to be retrofitted with a SCR-DENOX plant. The experience with the new firing system made in a 110 MW steam generator in Austria with a wide range of fuels is introduced. One of the largest bituminous coal fired once-trough steam generator built by EVT is the boiler for the power station Bexbach I (750 MW). The firing system is designed as a tangential firing system with 32 jet burners. These are arranged in pairs in the corners and divided into 4 burner levels with 4 burner pairs each. One mill is allocated to each burner level. An important characteristic feature is that the four bowl mills are arranged on one side of the steam generator. The plant is constructed with upper air nozzles which are arranged above the top burner level for the reduced of nitrogen oxides. During tests at steam generator with similar design, the nO x formation could be reduced from 750 to 500 mg/m 3 s.t.p. (dry, 6% O 2 ) with an addition of upper air of 20% at 100% unit capacity and constant total flow. As a main approach for the further reduction of the primary NO x emission at bituminous coal fired steam generators with tangential firing systems, the experience gained from the firing of brown coal has also been taken into account. A fundamental aspect in this respect was the vertical air staging in the direction of the furnace height. The results of many tests in a test reactor have shown that the differences of the achievable NO x values of brown and

  20. Solar Radiation effect on the bituminous binder

    International Nuclear Information System (INIS)

    Tadeo Rico, A.; Torres Perez, A.

    2010-01-01

    Asphalt, used as binder in road construction, becomes more brittle and harder during working life on the surface of the road pavement, conducting toward their deterioration. This is caused by the oxidation of the molecular functional groups of the asphalt molecular structure. Moreover, it is observed that ultraviolet radiation increases the oxidation process. However, the effect of solar light on the asphalt degradation has been poorly researched. The aim of this work is to study asphalt ageing caused by effect of solar radiation, by using standard test. Four commercial asphalts from different companies were selected: two with penetration number 50/70, and the other two polymer modified asphalts. From each of the asphalts forty samples were taken off and placed in four different aging conditions of temperature and radiation for a period ranging from 40 to 500 days. Ring and Ball test, and Fraass breaking Point test, were used to analyse the changes of asphalt properties after exposition to solar radiation. The results of the four analyzed asphalts showed a distinct behaviour; not only in the test temperature increase but also in the rate. Another experiment was carried out. Samples from a hot mix asphalt batch were placed under solar radiation, and were compacted by the Marshall procedure after increasing periods of time. Density and resistance to plastic flow using Marshall Apparatus were measured. Results showed an increase in the stability of samples under radiation. Both experiments show that the solar radiation is enough to cause changes in the asphalt molecular structure due to oxidation. So that, the study of the effect of the solar radiation on the asphalt properties could be a good tool to asses the performances of asphalt pavement. (Author) 26 refs.

  1. Maintenance Solutions for Bleeding and Flushed Pavements Surfaced with a Seal Coat or Surface Treatment

    Science.gov (United States)

    2007-02-01

    This report summarizes the findings of research directed at identifying maintenance solutions for bleeding and : flushed asphalt pavements surfaced with seal coats or surface treatments. Although the basic mechanism associated with : both bleeding an...

  2. [INVITED] Laser treatment of Inconel 718 alloy and surface characteristics

    Science.gov (United States)

    Yilbas, B. S.; Ali, H.; Al-Aqeeli, N.; Karatas, C.

    2016-04-01

    Laser surface texturing of Inconel 718 alloy is carried out under the high pressure nitrogen assisting gas. The combination of evaporation and melting at the irradiated surface is achieved by controlling the laser scanning speed and the laser output power. Morphological and metallurgical changes in the treated surface are analyzed using the analytical tools including optical, electron scanning, and atomic force microscopes, energy dispersive spectroscopy, and X-ray diffraction. Microhardnes and friction coefficient of the laser treated surface are measured. Residual stress formed in the surface region is determined from the X-ray diffraction data. Surface hydrophobicity of the laser treated layer is assessed incorporating the sessile drop method. It is found that laser treated surface is free from large size asperities including cracks and the voids. Surface microhardness increases significantly after the laser treatment process, which is attributed to the dense layer formation at the surface under the high cooling rates, dissolution of Laves phase in the surface region, and formation of nitride species at the surface. Residual stress formed is compressive in the laser treated surface and friction coefficient reduces at the surface after the laser treatment process. The combination of evaporation and melting at the irradiated surface results in surface texture composes of micro/nano-poles and pillars, which enhance the surface hydrophobicity.

  3. The Structure of Sandstones in Productive Horizons of the Permian Bituminous Deposits of Tatarstan (Russia

    Directory of Open Access Journals (Sweden)

    R.R. Khasanov

    2017-03-01

    Full Text Available The features of sandstones in productive horizons of the Permian bituminous deposits of Tatarstan (Russia have been considered. The composition and internal structure of sandstones have been studied by optical microscopy, electron paramagnetic resonance (EPR, and electron microscopy, as well as using a number of physical and chemical methods to solve special problems. The investigated sandstones belong to the greywacke group. The clastic material of sandstones contains grains of feldspar, quartz, mica, and particles of volcanic rocks. The nature and composition of cement are important parameters that determine the filtration-capacity properties of sedimentary rocks. Bituminous deposits are characterized by vertical zoning, which is expressed in the alternation of sites with varying degrees of cementation of rocks. Atten-tion has been also paid to post-sedimentation processes, such as pyritization and calcification. Pyrite forms rare xenomorphic isometric grains. The formation of pyrite occurs in diagenesis and is associated with the processes of biogenic sulfate reduction. The source of calcium for the crystallization of dispersed cal-cite in the porous space of sandstones is the underground waters of red-colored Ufimian deposits characterized by the alkaline properties favorable for calcium migration. According to the data of X-ray computed tomography, the internal space of the studied rocks is not homogeneous and represented by a system of communicated and isolated pores. In the studied samples, two types of organic matter differing in organic radicals have been detected. The first type is an organic substance of coal origin. The second type of organic matter belongs to the oil origin and refers to bitumens in its properties. The presence of a significant percentage of asphaltenes in the bitumen composition indicates the destruction of the oil substance in the near-surface conditions.

  4. Cellulose-containing Waste and Bituminized Salts

    International Nuclear Information System (INIS)

    Valcke, E.

    2005-01-01

    In Belgium, Medium-Level radioactive Waste (MLW) would be eventually disposed off in an underground repository in a geological formation such as the Boom Clay, which is studied as a reference host rock formation. MLW contains large quantities of non-radioactive chemicals that are released upon contact with pore water. It could be the case, for instance, for plutonium bearing cellulosic waste - such as paper tissues used to clean alpha glove boxes - issued from nuclear fuel fabrication (Belgonucleaire). At high pH, as in a disposal gallery backfilled with cement, the chemical degradation of cellulose will generate water-soluble products that may form strong complexes with actinides such as Am, Pu, Np, and U. This could lower the sorption of these elements onto the clay minerals, and hence increase their migration through the clay barrier. Another chemical perturbation could occur from the 3000 m 3 of so-called Eurobitum bituminised MLW, with precipitation sludges from the chemical treatment of spent nuclear fuel, and containing about 750 tons of NaNO 3 . The presence of NaNO 3 in this waste will give rise to several processes susceptible to affect the safety of the disposal system. Amongst others, it is necessary to verify that the swelling pressure of bitumen on the gallery wall and the osmotic pressure within the near-field are not too high to induce a fissuration of the host rock, leading to the formation of preferential migration pathways. The major objective of our work is to obtain a broad understanding of the different processes induced by the release of non-radioactive chemicals in the clay formation, to assess the chemical compatibility of different MLW forms with the clay

  5. Interim Enhanced Surface Water Treatment Rule Documents

    Science.gov (United States)

    The IESWTR balances the need for treatment with potential increases in disinfection by -products. The materials found on this page are intended to assist public water systems and state in the implementation of the IESWTR.

  6. Co-pyrolysis characteristic of biomass and bituminous coal.

    Science.gov (United States)

    Li, Shuaidan; Chen, Xueli; Liu, Aibin; Wang, Li; Yu, Guangsuo

    2015-03-01

    Co-pyrolysis characteristics of biomass and bituminous coal have been studied in this work. The temperature was up to 900°C with the heating rates of 10, 15, 20, 25 and 30°C/min. Rice straw, saw dust, microcrystalline cellulose, lignin and Shenfu bituminous coal were chosen as samples. Six different biomass ratios were used. The individual thermal behavior of each sample was obtained. The experimental weight fractions of the blended samples and the calculated values were compared. The results show that the weight fractions of the blended samples behave differently with calculated ones during the co-pyrolysis process. With the increasing biomass ratio, relative deviations between experimental weight fractions and calculated ones are larger. H/C molar ratio, heat transfer properties of biomass would affect to the interaction between biomass and coal. The maximum degradation rates are slower than the calculated ones. The activation energy distributions also changed by adding some biomass into coal. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Natural radioactivity associated with bituminous coal mining in Nigeria

    International Nuclear Information System (INIS)

    Balogun, F.A.; Mokobia, C.E.; Fasasi, M.K.; Ogundare, F.O.

    2003-01-01

    Gamma spectroscopic method was used to determine the natural radioactivity associated with the mining of Nigerian bituminous coal for the purpose of determining the radiological implications of coal mining in the country. The activity concentrations of the radionuclides detected range from 0.20±0.002 to 48.42±5.32 Bq kg -1 . The overall natural radionuclide contribution to the radioactivity of the environment was found to be 404.16±23.44 Bq kg -1 . Of this, coal waste (tailing) alone contributed 49.5% representing the largest contribution. Coal contributed just 5.5%. A comparison of the concentrations obtained in this work for coal with those from other parts of the world indicates that the radioactivity content of the Nigerian bituminous coal is not significantly different. The outdoor and indoor exposure rates in air 1 m above the ground are estimated to be (6.31±1.20)x10 -8 and (7.57±1.20) x10 -8 Gy h -1 , respectively, for the mining environment. These values compare very well with the global values reported by UNSCEAR: 5x10 -8 and 6x10 -8 Gy h -1 , respectively. The resulting annual effective dose equivalent estimated is (4.49±0.74)x10 -4 Sv yr -1 . This also compares favourably with the global value -4x10 -4 Sv yr -1 , reported by UNSCEAR

  8. Ultrasonic Surface Treatment of Titanium Alloys. The Submicrocrystalline State

    Science.gov (United States)

    Klimenov, V. A.; Vlasov, V. A.; Borozna, V. Y.; Klopotov, A. A.

    2015-09-01

    The paper presents the results of the research on improvement of physical-and- mechanical properties of titanium alloys VT1-0 and VT6 by modification of surfaces using ultrasonic treatment, and a comprehensive study of the microstructure and mechanical properties of modified surface layers. It has been established that exposure to ultrasonic treatment leads to formation in the surface layer of a structure with an average size of elements 50 - 100 nm, depending on the brand of titanium alloy.

  9. Effects of surface treatment on the properties of UV coating

    OpenAIRE

    Guo, Xiaolei; Li, Rongrong; Teng, Yu; Cao, Pingxiang; Wang, Xiaodong (Alice); Ji, Futang

    2015-01-01

    The influence of the surface treatment of raw medium-density fiberboard on the properties of 1st ultraviolet putty coating film and the effects of primer coating arrangement on the qualities of 1st ultraviolet primer film were investigated. With regard to surface roughness and the recorded adhesion of the coating film, there were significant variations when the surface treatment was modified or when the coating arrangement was changed. The findings led to the conclusion that there was a close...

  10. Atomic force microscopy analysis of different surface treatments of Ti dental implant surfaces

    International Nuclear Information System (INIS)

    Bathomarco, R.V.; Solorzano, G.; Elias, C.N.; Prioli, R.

    2004-01-01

    The surface of commercial unalloyed titanium, used in dental implants, was analyzed by atomic force microscopy. The morphology, roughness, and surface area of the samples, submitted to mechanically-induced erosion, chemical etching and a combination of both, were compared. The results show that surface treatments strongly influence the dental implant physical and chemical properties. An analysis of the length dependence of the implant surface roughness shows that, for scan sizes larger than 50 μm, the average surface roughness is independent of the scanning length and that the surface treatments lead to average surface roughness in the range of 0.37 up to 0.48 μm. It is shown that the implant surface energy is sensitive to the titanium surface area. As the area increases there is a decrease in the surface contact angle

  11. Effect of Surface Treatment on the Surface Characteristics of AISI 316L Stainless Steel

    Science.gov (United States)

    Trigwell, Steve; Selvaduray, Guna

    2005-01-01

    The ability of 316L stainless steel to maintain biocompatibility, which is dependent upon the surface characteristics, is critical to its effectiveness as an implant material. The surfaces of mechanically polished (MP), electropolished (EP) and plasma treated 316L stainless steel coupons were characterized by X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) for chemical composition, Atomic Force Microscopy for surface roughness, and contact angle measurements for critical surface tension. All surfaces had a Ni concentration that was significantly lower than the bulk concentration of -43%. The Cr content of the surface was increased significantly by electropolishing. The surface roughness was also improved significantly by electropolishing. Plasma treatment had the reverse effect - the surface Cr content was decreased. It was also found that the Cr and Fe in the surface exist in both the oxide and hydroxide states, with the ratios varying according to surface treatment.

  12. Atomic force microscopy analysis of different surface treatments of Ti dental implant surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bathomarco, R.V.; Solorzano, G.; Elias, C.N.; Prioli, R

    2004-06-30

    The surface of commercial unalloyed titanium, used in dental implants, was analyzed by atomic force microscopy. The morphology, roughness, and surface area of the samples, submitted to mechanically-induced erosion, chemical etching and a combination of both, were compared. The results show that surface treatments strongly influence the dental implant physical and chemical properties. An analysis of the length dependence of the implant surface roughness shows that, for scan sizes larger than 50 {mu}m, the average surface roughness is independent of the scanning length and that the surface treatments lead to average surface roughness in the range of 0.37 up to 0.48 {mu}m. It is shown that the implant surface energy is sensitive to the titanium surface area. As the area increases there is a decrease in the surface contact angle.

  13. A Novel Heat Treatment Process for Surface Hardening of Steel: Metal Melt Surface Hardening

    Science.gov (United States)

    Fu, Yong-sheng; Zhang, Wei; Xu, Xiaowei; Li, Jiehua; Li, Jun; Xia, Mingxu; Li, Jianguo

    2017-09-01

    A novel heat treatment process for surface hardening of steel has been demonstrated and named as "metal melt surface hardening (MMSH)." A surface layer with a thickness of about 400 μm and a hardness of about 700 HV has been achieved by ejecting AISI 304 stainless steel melt at a temperature of about 1783 K (1510 °C) onto the 40Cr steel surface. This proposed MMSH provides a very promising application for surface hardening of steel.

  14. Surface modification of steels by electrical discharge treatment in electrolyte

    International Nuclear Information System (INIS)

    Krastev, D.; Paunov, V.; Yordanov, B.; Lazarova, V.

    2013-01-01

    Full text: In this work are discussed some experimental data about the influence of applied electrical discharge treatment in electrolyte on the surface structure of steels. The electrical discharge treatment of steel surface in electrolyte gives a modified structure with specific combination of characteristics in result of nonequilibrium transformations. The modification goes by a high energy thermal process in a very small volume on the metallic surface involving melting, vaporisation, activation and alloying in electrical discharges, and after that cooling of this surface with high rate in the electrolyte. The surface layers obtain a different structure in comparison with the metal matrix and are with higher hardness, wear resistance and corrosion resistance. key words: surface modification, electrical discharge treatment in electrolyte, steels

  15. Effects of surface treatments on the translucency, opalescence, and surface texture of dental monolithic zirconia ceramics.

    Science.gov (United States)

    Kim, Hee-Kyung; Kim, Sung-Hun; Lee, Jai-Bong; Ha, Seung-Ryong

    2016-06-01

    Surface polishing or glazing may increase the appearance of depth of monolithic zirconia restorations. The purpose of this in vitro study was to investigate the effects of surface treatments on the translucency, opalescence, and surface texture of dental monolithic zirconia ceramics. Forty-five monolithic zirconia specimens (16.3×16.4×2.0 mm) were divided into groups I to V, according to the number of colorings each received. Each group was then divided into 3 subgroups (n=3) according to the surface treatment: N=no treatment; P=polished; and G=glazed. CIElab color coordinates were obtained relative to D65 on a reflection spectrophotometer. The translucency parameter (TP) and opalescence parameter (OP) were calculated. One specimen per subgroups I and V was selected for evaluation of surface roughness (Ra) and was examined with scanning electron microscopy (SEM). Data were analyzed with 2-way ANOVA and pairwise comparisons (α=.05). Statistical powers were verified to evaluate results (α=.05). The interaction effects of surface treatments combined with the number of colorings were significant for TP, OP, and Ra (P.05), whereas glazing significantly decreased OP and Ra in most groups. SEM images demonstrated that surface treatments affected the surface texture of monolithic zirconia ceramics. Surface treatments combined with coloring strongly affect the surface texture of dental monolithic zirconia ceramics. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  16. Surface treatment and protection method for cadmium zinc telluride crystals

    Science.gov (United States)

    Wright, Gomez W.; James, Ralph B.; Burger, Arnold; Chinn, Douglas A.

    2003-01-01

    A method for treatment of the surface of a CdZnTe (CZT) crystal that provides a native dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals. A two step process is disclosed, etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and after attachment of electrical contacts, passivating the CZT crystal surface with a solution of 10 w/o NH.sub.4 F and 10 w/o H.sub.2 O.sub.2 in water.

  17. Surface Treatment And Protection Method For Cadium Zinc Telluride Crystals

    Science.gov (United States)

    Wright, Gomez W.; James, Ralph B.; Burger, Arnold; Chinn, Douglas A.

    2006-02-21

    A method for treatment of the surface of a CdZnTe (CZT) crystal that provides a native dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals. A two step process is disclosed, etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and after attachment of electrical contacts, passivating the CZT crystal surface with a solution of 10 w/o NH4F and 10 w/o H2O2 in water.

  18. Superhydrophobic Copper Surfaces by Shot Peening and Chemical Treatment

    Science.gov (United States)

    Forooshani, H. Mojiri; Aliofkhazraei, M.; Rouhaghdam, A. Sabour

    In this paper, superhydrophobic surfaces are developed on polycrystalline copper using a combination of mechanical and chemical treatments by shot peening, dislocation etching and stearic acid treatment. The key point in this combined approach is the fabrication of a dislocation forest by shot peening. These sites were dissolved by etching, and hierarchical structures were fabricated. When these etched surfaces are treated by stearic acid, which has low surface energy, they become superhydrophobic with contact angle more than 150∘. Because of the superior properties and low costs involved with this method, it is expected to be widely used in the industry to fabricate superhydrophobic surfaces.

  19. Field evaluation of skid resistant surfaces : final report : part I.

    Science.gov (United States)

    1970-06-01

    This project was undertaken to establish a thin bituminous surface course that would possess good skid resistant qualities as well as, being both economical and durable. : This is the final report on the evaluation of skid resistant surfaces which wa...

  20. Effect of surface treatment of tailings on effluent quality

    International Nuclear Information System (INIS)

    Murray, D.R.; Okuhara, D.

    1980-01-01

    Lysimeters containing 125 tons of mine tailings were used to determine the impact of gravel, sawdust, and vegetation as surface treatments on the quality and quantity of effluent produced from sulfide-containing uranium mill tailings. Over a 5-yr period, treatments did not alter the effluent quality to a level acceptable to regulatory requirements. The concentration of iron, copper, lead, aluminum, and sulfate increased with the rise of acidity during this period. However, the rate and extent of changes did vary with the treatment. The role of surface treatment in long-term waste abandonment must be investigated further

  1. Surface hardening of AISI 4340 steel by electron beam treatment

    International Nuclear Information System (INIS)

    Wang Chienchun; Hwang Jiunren

    1994-01-01

    This paper investigates the effect of electron beam (EB) surface hardening on the abrasive wear property of AISI 4340 steel. The heat treatment conditions were varied so that the influence of microstructures on the wear resistance could be evaluated. A dry sand/rubber wheel abrasion test was selected to evaluate the high stress wear properties. The results show that the weight loss decreases with increasing hardness of surface layer or base material. The EB surface hardening can improve the abrasive wear resistance by about 10%. The best heat treatment process for AISI 4340 steel against abrasive wear is oil quenching from 840 C, tempering at 370 C, the EB surface hardening under heat input of 135-150 J mm -1 . The width and depth of the wear tracks are reduced after the EB surface hardening treatment. (orig.)

  2. Effect of surface treatment of tailings on effluent quality

    International Nuclear Information System (INIS)

    Murray, D.R.

    1980-01-01

    Successful reclamation treatment, in preparation for long range abandonment of mining wastes, involves both surface treatment and water quality control containment of waste solids and liquid contaminants. This paper describes use of lysimeters containing 125 tonnes of tailings to determine the impact of gravel, sawdust, and vegetation as surface treatments on the quality and quantity of effluent produced from sulphide-containing uranium mill tailings. Over a five-year period these treatments were observed and compared with bare tailings where no surface addition was made. The treatments did not alter the effluent quality to a level acceptable to regulatory requirements. Surface treatments did not appear to affect the leaching of Ra-226, NH 4 and NO 3 . The concentration of Fe, SO 4 , Cu, Pb, and Al increased with the rise of acidity as the pH changed from pH 9.5 to pH 2 in four and one-half years. However the rate and extent of changes of some of these parameters vary with the treatment. The experimental results for the observed trends are presented with limited explanation. Original design problems and unexpected delays in tailing reactions have made firm conclusions impossible at this stage. These data, however, provide a base for further investigation and development of explanations and firm conclusions, as to the role of surface treatment in long-term waste abandonment

  3. Study of thermal reactivity during bituminization of radioactive waste

    International Nuclear Information System (INIS)

    Mouffe, Sh.

    2004-10-01

    This work deals with the study of chemical reactions and phases transitions which can occur between magnesium nitrate, sodium nitrate, cobalt sulphur product, and nickel potassium ferrocyanide, when they are heated together during bituminization process of nuclear waste. The applied methodology associates a few techniques: temperature, enthalpy, and kinetics of reaction are determined by calorimetry, reaction products are characterised by chemical analyses, mass spectrometry and XRD analysis. Three fields of temperature and energy are observed in function of composition (one compound or a mixture of compounds). The study of reactions between NaNO 3 and cobalt sulphur product shows that the presence of water has got an effect on reaction temperature. The study of Mg(NO 3 ) 2 , 6 H 2 O and CoS shows an overlapping of different signals, and that the reaction rate is very slow (a few hours). (author)

  4. Environmental problems caused by bituminous schist and possible solutions

    International Nuclear Information System (INIS)

    Elmas, N.; Aykul, H.; Erarslan, K.; Ediz, I.G.

    1998-01-01

    Schist, as a disposal of mine, has harmful effects on environment. however, several manners can be utilized to prevent the environmental destruction as well as an economical benefit is gained. In this study, environmental problems caused by bituminous schist and other disposals have been investigated on a specific lignite coal mine where schist is disposed as waste material. Pollution and damage on land and in water sources around the coal district and the villages have been observed, recorded and several solutions to environmental problems have been proposed. Discussed proposals will not only solve the environmental pollution problem but also provide waste management facility. Industrial structure of the district enables such a disposal to be used as an economical raw material. Besides, general effects of the coal mine and the power plant nearby have been discussed from environmental point of view, too. 7 refs

  5. Application of infrared camera to bituminous concrete pavements: measuring vehicle

    Science.gov (United States)

    Janků, Michal; Stryk, Josef

    2017-09-01

    Infrared thermography (IR) has been used for decades in certain fields. However, the technological level of advancement of measuring devices has not been sufficient for some applications. Over the recent years, good quality thermal cameras with high resolution and very high thermal sensitivity have started to appear on the market. The development in the field of measuring technologies allowed the use of infrared thermography in new fields and for larger number of users. This article describes the research in progress in Transport Research Centre with a focus on the use of infrared thermography for diagnostics of bituminous road pavements. A measuring vehicle, equipped with a thermal camera, digital camera and GPS sensor, was designed for the diagnostics of pavements. New, highly sensitive, thermal cameras allow to measure very small temperature differences from the moving vehicle. This study shows the potential of a high-speed inspection without lane closures while using IR thermography.

  6. Kwik Bond Polymers(R) high friction surface treatment.

    Science.gov (United States)

    2015-12-01

    High friction surface treatment (HFST) was applied to two on-ramps in the Seattle urban area to improve : friction resistance. The ramps were high accident locations. The system applied was polyester resin binder and : calcined bauxite aggregate. Tes...

  7. Cleaning of diffusion bonding surface by argon ion bombardment treatment

    Science.gov (United States)

    Wang, Airu; Ohashi, Osamu; Yamaguchi, Norio; Aoki, Masanori; Higashi, Yasuo; Hitomi, Nobuteru

    2003-05-01

    The specimens of oxygen-free high conductivity copper, SUS304L stainless steel and pure iron were treated by argon ion bombardment and then were bonded by diffusion bonding method. The effects of argon ion bombardment treatment on faying surface morphology, tensile strength of bonding joints and inclusions at the fracture surface were investigated. The results showed that argon ion bombardment treatment was effective to remove the oxide film and contamination at the faying surface and improve the quality of joints. The tensile strength of the bonded joints was improved, and minimum bonding temperature to make the metallic bonding at the interface was lowered by argon ion bombardment treatment. At the joints with argon ion bombardment treatment, ductile fractured surface was seen and the amount of inclusions was obviously decreased.

  8. Alternative aggregates and materials for high friction surface treatments.

    Science.gov (United States)

    2016-05-01

    The State of Florida has used high friction surface treatments (HFSTs) since 2006 to reduce wet weather crashes on : tight curves and intersections and to maintain bridge decks; however, the Florida Department of Transportation : (FDOT) has reported ...

  9. Dielectric barrier discharge plasma treatment of cellulose nanofibre surfaces

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Madsen, Bo; Berglund, Linn

    2017-01-01

    Dielectric barrier discharge plasma treatment was applied to modify cellulose nanofibre (CNF) surfaces with and without ultrasonic irradiation. The plasma treatment improved the wetting by deionised water and glycerol, and increased the contents of oxygen, carbonyl group, and carboxyl group...... and amorphous phases. Ultrasonic irradiation also improved the uniformity of the treatment. Altogether, it is demonstrated that atmospheric pressure plasma treatment is a promising technique to modify the CNF surface before composite processing....... on the nanofibre surface. Ultrasonic irradiation further enhanced the wetting and oxidation of the nanofibre coating. Scanning electron microscopic observations showed skeleton-like features on the plasma-treated surface, indicating preferential etching of weaker domains, such as low-molecular weight domains...

  10. Coatings and Surface Treatments for Reusable Entry Systems

    Science.gov (United States)

    Johnson, Sylvia M.

    2016-01-01

    This talk outlines work in coatings for TPS done at NASA Ames. coatings and surface treatments on reusable TPS are critical for controlling the behavior of the materials. coatings discussed include RCG, TUFI and HETC. TUFROc is also discussed.

  11. Surface treatment of nanocrystal quantum dots after film deposition

    Science.gov (United States)

    Sykora, Milan; Koposov, Alexey; Fuke, Nobuhiro

    2015-02-03

    Provided are methods of surface treatment of nanocrystal quantum dots after film deposition so as to exchange the native ligands of the quantum dots for exchange ligands that result in improvement in charge extraction from the nanocrystals.

  12. The effects of surface treatments on rapid chloride permeability tests

    KAUST Repository

    Yoon, Seyoon

    2012-08-01

    Surface treatments are commonly applied to improve the chloride resistance of concrete structures exposed to saline environments. Information on chloride ingress to surface-treated concrete is mostly provided by application of the rapid chloride permeability test (RCPT); this test is short in duration and provides rapid results. This study presents a numerical formulation, based on the extended Nernst-Plank/Poisson (NPP) equation, to model the effect of the surface treatment on a sample tested by RCPT. Predictions of the model are compared to experimental measurements. The simulations show that the results from RCPT, in terms of ionic profiles and measurement of the electric field, are dependent on the effectiveness of surface treatments. During RCPT, highly effective surface treatments cause both cations and anions to flocculate at the interface between the surface treatment and the concrete, creating a local electric field. Our numerical model includes these phenomena and presents a methodology to obtain more accurate diffusivities of the surface-treated- concrete from RCPT. © 2012 Elsevier B.V. All rights reserved.

  13. Bonding to zirconia using a new surface treatment

    NARCIS (Netherlands)

    Aboushelib, M.N.; Feilzer, A.J.; Kleverlaan, C.J.

    2010-01-01

    Purpose: Selective infiltration etching (SIE) is a newly developed surface treatment used to modify the surface of zirconia-based materials, rendering them ready for bonding to resin cements. The aim of this study was to evaluate the zirconia/resin bond strength and durability using the proposed

  14. Influence of association of "EVA-NBR" on indirect tensile strength of modified bituminous concrete

    Science.gov (United States)

    Chinoun, M.; Soudani, K.; Haddadi, S.

    2016-04-01

    The aim of this work is to contribute to the improvement of the mechanical properties of bituminous concrete by modification of bituminous concrete. In this study, we present the results of the indirect tensile strength "ITS" of modified bituminous concrete by the combination of two modifiers, one is a plastomer EVA (Ethylene Vinyl Acetate) and the other is a industrial waste from the shoe soles grinding NBR (Nitrile Butadiene Rubber) as crumb rubber. To modify the bitumen a wet process was used. The results show that the modification of bitumen by EVA-NBR combination increases their resistance to the indirect traction "ITS" compared to the bituminous concrete control. The mixture of 5% [50% EVA+ 50% NBR] is given the best result among the other associations.

  15. A new radiometric instrument designed to measure the parameters of bituminous coal on transport belts

    International Nuclear Information System (INIS)

    Kubicek, P.

    1993-01-01

    A new radiometric instrument developed in Czechoslovakia, for the measurement of ash content of bituminous coal, and for the determination of approximate values of moisture and weight is described. (Author)

  16. Investigation on Using SBS and Active Carbon Filler to Reduce the VOC Emission from Bituminous Materials

    OpenAIRE

    Cui, Peiqiang; Wu, Shaopeng; Li, Fuzhou; Xiao, Yue; Zhang, Honghua

    2014-01-01

    Bituminous materials are playing a vital role in pavement design and the roofing industry because of outstanding properties. Unfortunately, bituminous materials will release volatile organic compounds (VOC), making them non-environmentally friendly. Therefore, technologies that can be used to decrease the VOC emission are urgently required. In this research, the VOC emission and material behaviors were analyzed and compared to investigate the possibility of adding styrene butadiene styrene (S...

  17. Improvement of crystalline silicon surface passivation by hydrogen plasma treatment

    International Nuclear Information System (INIS)

    Martin, I.; Vetter, M.; Orpella, A.; Voz, C.; Puigdollers, J.; Alcubilla, R.; Kharchenko, A.V.; Roca i Cabarrocas, P.

    2004-01-01

    A completely dry low-temperature process has been developed to passivate 3.3 Ω cm p-type crystalline silicon surface with excellent results. Particularly, we have investigated the use of a hydrogen plasma treatment, just before hydrogenated amorphous silicon carbide (a-SiC x :H) deposition, without breaking the vacuum. We measured effective lifetime, τ eff , through a quasi-steady-state photoconductance technique. Experimental results show that hydrogen plasma treatment improves surface passivation compared to classical HF dip. S eff values lower than 19 cm s -1 were achieved using a hydrogen plasma treatment and an a-SiC x :H film deposited at 300 deg. C

  18. PITTING CORROSION OF STAINLESS STEEL AT THE VARIOUS SURFACE TREATMENT

    Directory of Open Access Journals (Sweden)

    Viera Zatkalíková

    2011-09-01

    Full Text Available The stainless steel surface treatment is very important with regard to its pitting corrosion susceptibility. An effect of various types surfacing on pitting corrosion resistance of AISI 304stainless steel is investigated in this work. The samples of the tested material are turned, blasted, peened, grinded and a half of them are pickled to achieve higher purity of surfaces and better quality of passive film. Eight types of different finished surfaces are tested by electrochemical and immersion tests to determine corrosion behaviour in conditions where pitting is evoked by controlled potential and second by solution with high redox potential. By this way the effect of mechanical and chemical surface treatment on the resistance to pitting corrosion, character, size and shape of pits are compared in the conditions of different mechanisms of corrosion process.

  19. Numerical treatment of free surface problems in ferrohydrodynamics

    International Nuclear Information System (INIS)

    Lavrova, O; Matthies, G; Mitkova, T; Polevikov, V; Tobiska, L

    2006-01-01

    The numerical treatment of free surface problems in ferrohydrodynamics is considered. Starting from the general model, special attention is paid to field-surface and flow-surface interactions. Since in some situations these feedback interactions can be partly or even fully neglected, simpler models can be derived. The application of such models to the numerical simulation of dissipative systems, rotary shaft seals, equilibrium shapes of ferrofluid drops, and pattern formation in the normal-field instability of ferrofluid layers is given. Our numerical strategy is able to recover solitary surface patterns which were discovered recently in experiments

  20. Evaluation of Cellulosic Fabrics Surface Characteristics after Different Treatments

    OpenAIRE

    Vitalija MASTEIKAITĖ; Ulzan SMAILOVA; Maira NURZHASAROVA; Virginija SACEVIČIENĖ; Tadas KLEVECKAS

    2014-01-01

    Various clothes treatments during their manufacture and wear change the fabrics physical and surface characteristics. The different testing methods for fabrics quality evaluation are used in this research. The aim of this work is to examine the effect of enzyme treatment, laundering and abrasion on the appearance of different cellulosic fabrics. Six cotton and cotton blend woven fabrics used for faded garments production were chosen for this examination. Treatments such, as enzyme wash, domes...

  1. Surface modification of multiwall carbon nanotubes by sulfonitric treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gómez, Sofía, E-mail: sofiagomez@cetmic.unlp.edu.ar [Centro de Tecnología de Recursos Minerales y Cerámica (CETMIC), Camino Centenario y 506, C.C.49, M.B. Gonnet B1897ZCA (Argentina); Rendtorff, Nicolás M., E-mail: rendtorff@cetmic.unlp.edu.ar [Centro de Tecnología de Recursos Minerales y Cerámica (CETMIC), Camino Centenario y 506, C.C.49, M.B. Gonnet B1897ZCA (Argentina); Departamento de Química, Facultad de Ciencias Exactas—UNLP, Calle 115 y 47, La Plata 1900 (Argentina); Aglietti, Esteban F., E-mail: eaglietti@cetmic.unlp.edu.ar [Centro de Tecnología de Recursos Minerales y Cerámica (CETMIC), Camino Centenario y 506, C.C.49, M.B. Gonnet B1897ZCA (Argentina); Departamento de Química, Facultad de Ciencias Exactas—UNLP, Calle 115 y 47, La Plata 1900 (Argentina); Sakka, Yoshio, E-mail: SAKKA.Yoshio@nims.go.jp [National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan); Suárez, Gustavo, E-mail: gsuarez@cetmic.unlp.edu.ar [Centro de Tecnología de Recursos Minerales y Cerámica (CETMIC), Camino Centenario y 506, C.C.49, M.B. Gonnet B1897ZCA (Argentina); Departamento de Química, Facultad de Ciencias Exactas—UNLP, Calle 115 y 47, La Plata 1900 (Argentina)

    2016-08-30

    Highlights: • After the acid treatment highly increase the amount carbonyl and carboxylic groups. • The oxidation of MWCNT generates a high negative charge of it in all the pH range. • It could achieve a good dispersion of the MWCNT in water-based suspension. • There is morphological damage on the surfaces of MWCNT after the acid treatment. • Some surface defects but no shortening were observed by TEM images. - Abstract: Carbon nanotubes are widely used for electronic, mechanical, and optical devices due to their unique structural and quantum characteristics. The species generated by oxidation on the surface of these materials permit binding new reaction chains, which improves the dispersibility, processing and compatibility with other materials. Even though different acid treatments and applications of these CNT have been reported, relatively few research studies have focused on the relationship between the acid treatment and the formation of nanodefects, specific oxidized species or CNT surface defects. In this work, multiwall carbon nanotube (MWCNT) oxidation at 90 °C was characterized in order to determine the acid treatment effect on the surface. It was found that oxidized species are already present in MWCNT without an acid treatment, but there are not enough to cause water-based dispersion. The species were identified and quantified by infrared spectroscopy and X-ray photoelectron spectroscopy. Also, transmission electron microscopy observations showed not only modifications of the oxidized species, but also morphological damage on the surfaces of MWCNT after being subjected to the acid treatment. This effect was also confirmed by Raman spectroscopy. The acid treatment generates higher oxidized species, decreasing the zeta potential in the whole pH range.

  2. Study on hydrophilicity of polymer surfaces improved by plasma treatment

    International Nuclear Information System (INIS)

    Lai Jiangnan; Sunderland, Bob; Xue Jianming; Yan, Sha; Zhao Weijiang; Folkard, Melvyn; Michael, Barry D.; Wang Yugang

    2006-01-01

    Surface properties of polycarbonate (PC), polypropylene (PP), polyethylene terephthalate (PET) samples treated by microwave-induced argon plasma have been studied with contact angle measurement, X-ray photoelectron spectroscopy (XPS) and scanned electron microscopy (SEM). It is found that plasma treatment modified the surfaces both in composition and roughness. Modification of composition makes polymer surfaces tend to be highly hydrophilic, which mainly depended on the increase of ratio of oxygen-containing group as same as other papers reported. And this experiment further revealed that C=O bond is Key factor to the improvement of the hydrophilicity of polymer surfaces. Our SEM observation on PET shown that the roughness of the surface has also been improved in micron scale and it has influence on the surface hydrophilicity

  3. Theme day: corrosion and surface treatments in nuclear facilities. Proceedings

    International Nuclear Information System (INIS)

    2012-02-01

    This document brings together the available presentations given at the theme day organized by the Bourgogne Nuclear Pole on the topic of corrosion and surface treatments in nuclear facilities. Eleven presentations (slides) are compiled in this document: 1 - Introduction - PNB centre of competitiveness and R and D activities (A. Mantovan, PNB); 2 - Corrosion damage (M. Foucault, Areva NP - Centre Technique Le Creusot); 3 - Corrosion mechanisms (R. Oltra, UB-ICB); 4 - Examples of expertise management (C. Duret-Thual, Institut de la corrosion/Corrosion Institute); 5 - General framework of surface treatments (C. Nouveau, ENSAM Cluny Paris Tech); 6 - Surfaces et interfaces characterisation - Part A (C. Langlade, Y. Gachon, UTBM and HEF); 7 - Surfaces et interfaces characterisation - Part B (C. Langlade, Y. Gachon, UTBM and HEF); 8 - Ion beam surface treatment (Y. Le Guellec, Quertech Ingenierie); 9 - Impact surface treatment (G. Saout, Sonats); 10 - Metal oxides Characterisation by US laser (R. Oltra, UB-ICB); 11 - Detection and Characterisation of intergranular corrosion (Y. Kernin, Stephane Bourgois, Areva Intercontrole)

  4. Bituminous reference document: synthesis of knowledge on the long time behavior of bituminous packages; Dossier de reference bitume: synthese des connaissances sur le comportement a long terme des colis bitumes

    Energy Technology Data Exchange (ETDEWEB)

    Sercombe, J.; Adenot, F.; Vistoli, P.P.; Parraud, S.; Riglet-Martial, C.; Gwinner, B.; Felines, I.; Tiffreau, C.; Libert, M

    2004-07-01

    This document is a synthesis of the knowledge acquired at the CEA on the behavior of bituminous packages. In this framework, the CEA studied bituminous packages in generic conditions of a package lifetime. The main factors, the evolution mechanisms and influential parameters have been determined and quantitative s simulation have been developed. After a description of the main initial bituminous packages characterizations, the evolutions in saturated and un-saturated environment are exposed. (A.L.B.)

  5. Surface improvement of EPDM rubber by plasma treatment

    International Nuclear Information System (INIS)

    Moraes, J H; Silva Sobrinho, A S da; Maciel, H S; Dutra, J C N; Massi, M; Mello, S A C; Schreiner, W H

    2007-01-01

    The surface of ethylene-propylene-diene monomer (EPDM) rubber was treated in N 2 /Ar and N 2 /H 2 /Ar RF plasmas in order to achieve similar or better adhesion properties than NBR (acrylonitrile-butadiene) rubber, nowadays used as thermal protection of rocket chambers. The surface properties were studied by contact angle measurements and by x-ray photoelectron spectroscopy (XPS). The treated surfaces of the EPDM samples show a significant reduction in the contact angle measurement, indicating an increase in the surface energy. XPS analyses show the incorporation of polar nitrogen- and oxygen-containing groups on the rubber surface. After plasma treatment the presence of oxygen is observed due to surface oxidation which occurs when the samples are exposed to the air. Atomic force microscopy and scanning electron microscopy analyses indicate a decrease in the EPDM rubber surface roughness, promoted by surface etching during the plasma treatment. Strength tests indicate improvement of about 30% and 110% in the adhesion strength for the plasma treated EPDM/polyurethane liner interface and for the EPDM/epoxy adhesive interface, respectively. The adhesion strength of the EPDM/liner is similar to that obtained for the NBR/liner, which indicates that EPDM rubber can safely be used as thermal protection of the solid propellant rocket chamber

  6. The morphology of coconut fiber surface under chemical treatment

    OpenAIRE

    Arsyad, Muhammad; Wardana, I Nyoman Gede; Pratikto,; Irawan, Yudy Surya

    2015-01-01

    The objective of this study was to determine the effect of chemical treatment on the coconut fiber surface morphology. This study is divided into three stages, preparation of materials, treatment and testing of coconut fiber. The first treatment is coconut fiber soaked in a solution of NaOH for 3 hours with concentration, respectively 5%, 10%, 15%, and 20%. The second treatment is coconut fiber soaked in KMnO4 solution with a concentration of 0.25%, 0.5%, 0.75%, and 1% for 3 hours. The third ...

  7. Surface Modification of Polymeric Materials by Plasma Treatment

    Directory of Open Access Journals (Sweden)

    E.F. Castro Vidaurre

    2002-03-01

    Full Text Available Low-temperature plasma treatment has been used in the last years as a useful tool to modify the surface properties of different materials, in special of polymers. In the present work low temperature plasma was used to treat the surface of asymmetric porous substrates of polysulfone (PSf membranes. The main purpose of this work was to study the influence of the exposure time and the power supplied to argon plasma on the permeability properties of the membranes. Three rf power levels, respectively 5, 10 and 15 W were used. Treatment time ranged from 1 to 50 min. Reduction of single gas permeability was observed with Ar plasma treatments at low energy bombardment (5 W and short exposure time (20 min. Higher power and/or higher plasma exposition time causes a degradation process begins. The chemical and structural characterization of the membranes before and after the surface modification was done by AFM, SEM and XPS.

  8. An alternative treatment of occlusal wear: Cast metal occlusal surface

    OpenAIRE

    Sandeep Kumar; Aman Arora; Reena Yadav

    2012-01-01

    Acrylic resin denture teeth often exhibit rapid occlusal wear, which may lead to decrease in the chewing efficiency, loss of vertical dimension of occlusion, denture instability, temporomandibular joint disturbances, etc. There are various treatment options available like, use of highly cross linked acrylic teeth, amalgam or metal inserts on occlusal surface, use of composite, gold or metal occlusal surface, etc. Several articles have described methods to construct gold and metal occlusal sur...

  9. Assessment of an Impulse GPR Antenna Abilities in Investigation of Transversal Cracks of the Bituminous Pavement

    Science.gov (United States)

    Krysiński, L.; Sudyka, J.

    2012-04-01

    generation or to explain reasons of lacking signal. The three field cases represent different types of bituminous pavement and different degrees of cracking process progress, what showed first of all a large diversity GPR responses types and existence of specific masking effect related possibly to large-size granulation of the asphalt mixture. These examples show that the strong signals are frequently related to advanced deterioration in lower, older layers and confirm difficulty of cracks detection in a new cover. But on other hand long term observation showed that numerous new cracks appear on the surface in places, where some structural singularities were noticed earlier inside the new construction.

  10. Surface oxide formation during corona discharge treatment of AA 1050 aluminium surfaces

    DEFF Research Database (Denmark)

    Minzari, Daniel; Møller, Per; Kingshott, Peter

    2008-01-01

    process modifies aluminium AA 1050 surface, the oxide growth and resulting corrosion properties. The corona treatment is carried out in atmospheric air. Treated surfaces are characterized using XPS, SEM/EDS, and FIB-FESEM and results suggest that an oxide layer is grown, consisting of mixture of oxide...... and hydroxide. The thickness of the oxide layer extends to 150–300 nm after prolonged treatment. Potentiodynamic polarization experiments show that the corona treatment reduces anodic reactivity of the surface significantly and a moderate reduction of the cathodic reactivity.......Atmospheric plasmas have traditionally been used as a non-chemical etching process for polymers, but the characteristics of these plasmas could very well be exploited for metals for purposes more than surface cleaning that is presently employed. This paper focuses on how the corona discharge...

  11. Semiconductor surface and interface passivation by cyanide treatment

    Science.gov (United States)

    Kobayashi, H.; Takahashi, M.; Maida, O.; Asano, A.; Kubota, T.; Ivančo, J.; Nakajima, A.; Akimoto, K.

    2004-08-01

    Cyanide treatment which simply involves immersion of semiconductors in cyanide solutions can passivate interface states as well as surface states. When Si surfaces are treated with KCN solutions, a surface photovoltage greatly increases, and the surface recombination velocity is calculated to be decreased from ˜3000 cm/s to less than 200 cm/s. When the cyanide treatment is applied to ultrathin SiO 2/single-crystalline Si structure, interface states are passivated. The passivation of the SiO 2/Si interface states increases the energy conversion efficiency of MOS solar cells to 16.2% and decreases the leakage current density for MOS diodes to 1/3-1/8. When the cyanide treatment is performed on polycrystalline (poly-) Si, defect states in Si up to at least 0.5 μm depth from the surface are passivated, resulting in a vast increase in the energy conversion efficiency of solar cells and a decrease in the dark current density of MOS diodes to 1/100-1/15 that without cyanide treatment. The defect passivation is attributed to the formation of SiCN bonds from defect states. SiCN bonds are found not to be ruptured by heat treatment at 800 °C and AM 1.5 100 mW/cm 2 irradiation for more than 1000 h. Density functional calculations show that the thermal and irradiation stability results from strong SiCN bonds with the bond energy of 4.5 eV. When the cyanide treatment is performed on oxide/GaAs(1 0 0) structure, the interface state density decreases to ˜50%. The cyanide treatment can also passivate defect states in Cu 2O films, resulting in increases in the carrier density and the band-to-band photoluminescence intensity.

  12. Laser treatment of boron carbide surfaces: Metallurgical and morphological examinations

    Energy Technology Data Exchange (ETDEWEB)

    Yilbas, B.S., E-mail: bsilbas@kfupm.edu.sa; Karatas, C.

    2014-08-01

    Highlights: • Dense layer with fine grains is formed at surface. • Irregular shaped grains and dendrites are formed below dense layer. • Assisting gas forms nitride species (BN and BC{sub 2}N) at surface. • Fracture toughness of treated surface reduces because of high hardness. • Residual stress is compressive and the maximum residual stress is about 0.9 GPa. - Abstract: Laser treatment of B{sub 4}C tile surfaces is carried out under high pressure nitrogen assisting gas environment. Morphological and metallurgical changes in the laser treated layer are examined by incorporating scanning electron microscope, energy dispersive spectroscopy, and X-ray diffraction. Microhardness and fracture toughness of the laser treated surface are determined from the indentation data. Residual stress formed at the treated surface is obtained by using X-ray diffraction technique. It is found that laser treated surface is free from large scale asperities including cracks and voids; however, some locally scattered shallow cavities with 1.5–2 μm widths are formed at the surface because of high temperature processing. Dense layer, consisting of fine grains, and formation of nitride species (BN and BC{sub 2}N) enhance microhardness and lower fracture toughness at the surface. Residual stress formed in the treated layer is compressive and the maximum residual stress is in the order of −0.9 GPa.

  13. Surface treatment of CFRP composites using femtosecond laser radiation

    Science.gov (United States)

    Oliveira, V.; Sharma, S. P.; de Moura, M. F. S. F.; Moreira, R. D. F.; Vilar, R.

    2017-07-01

    In the present work, we investigate the surface treatment of carbon fiber-reinforced polymer (CFRP) composites by laser ablation with femtosecond laser radiation. For this purpose, unidirectional carbon fiber-reinforced epoxy matrix composites were treated with femtosecond laser pulses of 1024 nm wavelength and 550 fs duration. Laser tracks were inscribed on the material surface using pulse energies and scanning speeds in the range 0.1-0.5 mJ and 0.1-5 mm/s, respectively. The morphology of the laser treated surfaces was investigated by field emission scanning electron microscopy. We show that, by using the appropriate processing parameters, a selective removal of the epoxy resin can be achieved, leaving the carbon fibers exposed. In addition, sub-micron laser induced periodic surface structures (LIPSS) are created on the carbon fibers surface, which may be potentially beneficial for the improvement of the fiber to matrix adhesion in adhesive bonds between CFRP parts.

  14. Development of bituminous coal chambers with respect to throughput

    Energy Technology Data Exchange (ETDEWEB)

    Schappert, H.

    1942-10-17

    This short report compared three coal liquefaction plants in Germany which operated principally on bituminous coal and which had been built a few years apart in time. From the earliest plant (Scholven) to the latest (Blechhammer), the liquid-phase throughput had been almost tripled, partly because of the change from 300-atm to 700-atm operation, and partly because of the use of heat exchange to heat the coal paste part way to reaction temperature. This introduction of coal paste heat exchange reduced the load on preheaters so much that the amount of heat necessary in the preheater to heat one (metric) ton of coal paste to reaction temperature was reduced from 320,000 kcal to 170,000 kcal. Another development in the middle plant (Gelsenberg) was the addition of a portion of the cold coal paste at the input to the second reaction oven in each chamber, letting the heat of reaction itself heat that paste to reaction temperature (and at the same time regulating the temperature of the reaction better). Finally it was noted that for the production of a given amount of synthetic fuel, Blechhammer needed only about half as many reaction chambers as did Scholven.

  15. The hydrogasification of lignite and sub-bituminous coals

    Science.gov (United States)

    Bhatt, B.; Fallon, P. T.; Steinberg, M.

    1981-02-01

    A North Dakota lignite and a New Mexico sub-bituminous coal have been hydrogenated at up to 900°C and 2500 psi hydrogen pressure. Yields of gaseous hydrocarbons and aromatic liquids have been studied as a function of temperature, pressure, residence time, feed rates and H2/coal ratio. Coal feed rates in excess of 10 lb/hr have been achieved in the 1 in. I. D.×8 ft reactor and methane concentration as high as 55% have been observed. A four-step reaction model was developed for the production and decomposition of the hydrocarbon products. A single object function formulated from the weighted errors for the four dependent process, variables, CH4, C2H6, BTX, and oil yields, was minimized using a program containing three independent iterative techniques. The results of the nonlinear regression analysis for lignite show that a first-order chemical reaction model with respect to C conversion satisfactorily describes the dilute phase hydrogenation. The activation energy for the initial products formation was estimated to be 42,700 cal/gmole and the power of hydrogen partial pressure was found to be +0.14. The overall correlation coefficient was 0.83. The mechanism, the rate expressions, and the design curves developed can be used for scale-up and reactor design.

  16. A process for the bituminization of radioactive wastes

    International Nuclear Information System (INIS)

    Bar-Ziv, E.; Manor, D.; Levin, I.

    1977-06-01

    A process is described for the incorporation of sodium nitrate solutions in bitumen, with a view to the bituminization of radioactive wastes. This process has involved the development of a chemical process and its technological application. A double jacket reactor equipped with an anchor-type stirrer has been built. Sodium nitrate (NaNO 3 ) solutions with sodium hydroxide (NaOH) are fed into the reactor simultaneously with a bitumen emulsion while heated oil is circulated through the double jacket. After all the water has evaporated, the mixture is ''simmered'' at 170/180 deg C for up to 5 hours in order to get a homogeneous product which will be suitable for final storage. The product contains small salt crystals (10/50 μm) and has high viscosity (200/2000 poise at 160 deg C and 12 rpm), so that the possibility of sedimentation is eliminated. In comparative experiments with molten bitumen, large salt aggregates, inhomogeneously distributed, make the product unsuitable. It has been found that NaOH is responsible for the polimerization of the bitumen, which raises its viscosity. The degree of polimerization depends on the NaOH concentration and ''simmering'' time and temperature. NaOH is added to NaNO 3 in order to raise the mixture's viscosity and thereby prevent sedimentation

  17. Chemical and Pyrolytic Thermogravimetric Characterization of Nigerian Bituminous Coals

    Directory of Open Access Journals (Sweden)

    Nyakuma Bemgba Bevan

    2016-12-01

    Full Text Available The discovery of new coal deposits in Nigeria presents solutions for nation’s energy crises and prospects for socioeconomic growth and sustainable development. Furthermore, the quest for sustainable energy to limit global warming, climate change, and environmental degradation has necessitated the exploration of alternatives using cleaner technologies such as coal pyrolysis. However, a lack of comprehensive data on physico-chemical and thermal properties of Nigerian coals has greatly limited their utilization. Therefore, the physico-chemical properties, rank (classification, and thermal decomposition profiles of two Nigerian bituminous coals – Afuze (AFZ and Shankodi-Jangwa (SKJ – were examined in this study. The results indicate that the coals contain high proportions of C, H, N, S, O and a sufficiently high heating value (HHV for energy conversion. The coal classification revealed that the Afuze (AFZ coal possesses a higher rank, maturity, and coal properties compared to the Shankodi-Jangwa (SKJ coal. A thermal analysis demonstrated that coal pyrolysis in both cases occurred in three stages; drying (30-200 °C, devolatilization (200-600 °C, and char decomposition (600-1000 °C. The results also indicated that pyrolysis at 1000 °C is not sufficient for complete pyrolysis. In general, the thermochemical and pyrolytic fuel properties indicate that the coal from both places can potentially be utilized for future clean energy applications.

  18. Temperature induced development of porous structure of bituminous coal chars at high pressure

    Directory of Open Access Journals (Sweden)

    Natalia Howaniec

    2016-01-01

    Full Text Available The porous structure of chars affects their reactivity in gasification, having an impact on the course and product distribution of the process. The shape, size and connections between pores determine the mechanical properties of chars, as well as heat and mass transport in thermochemical processing. In the study the combined effects of temperature in the range of 973–1273 °K and elevated pressure of 3 MPa on the development of porous structure of bituminous coal chars were investigated. Relatively low heating rate and long residence time characteristic for the in-situ coal conversion were applied. The increase in the temperature to 1173 °K under pressurized conditions resulted in the enhancement of porous structure development reflected in the values of the specific surface area, total pore volume, micropore area and volume, as well as ratio of the micropore volume to the total pore volume. These effects were attributed to the enhanced vaporization and devolatilization, as well as swelling behavior along the increase of temperature and under high pressure, followed by a collapse of pores over certain temperature value. This proves the strong dependence of the porous structure of chars not only on the pyrolysis process conditions but also on the physical and chemical properties of the parent fuel.

  19. Characteristic Study of Shenmu Bituminous Coal Combustion with Online TG-MS-FTIR

    Science.gov (United States)

    Pan, Guanfu

    2018-01-01

    The combustion characteristics of Shenmu bituminous pulverized coal (SBC) were comprehensively investigated with a combined TG-MS-FTIR system by considering the effect of particle size, heating rate and total flowrate. The combustion products were accurately quantified by normalization and numerical analysis of MS results. The results indicate that the decrease of the particle size, heating rate and total flowrate result in lower ignition and burnout temperatures. The activation energy tends to be lower with smaller particle size, lower heating rate and total flowrate. The MS and FTIR results demonstrate that lower concentrations of different products, such as NO, NO2, HCN, CH4 and SO2 were produced with smaller particle size, slower heating rate and lower total flowrate. The decrease of particle size would lead to more contact area with oxygen and slower heating rate could provide more sufficient time for the diffusion. High total flowrate would reduce the oxygen adsorbability on the coal particle surface and shorten the residence time of oxygen, which makes the ignition difficult to occur. This work will guide to understand the combustion kinetics of pulverized coals and be beneficial to control the formation of pollutants.

  20. Using a nitrogen dielectric barrier discharge for surface treatment

    International Nuclear Information System (INIS)

    Borcia, G; Anderson, C A; Brown, N M D

    2005-01-01

    In this paper, continuing previous work, we report on the installation and the testing of an experimental dielectric barrier discharge (DBD) reactor run in a controlled atmospheric pressure gaseous environment other than air. Here, the effects of a N 2 -DBD treatment on the surface of a test polymer material (UHMW polyethylene) are examined, reported, discussed and compared to results obtained previously following air-DBD treatment. Surface analysis and characterization were performed using x-ray photoelectron spectroscopy, contact angle measurement and scanning electron microscopy before and following the DBD processing described. The discharge parameters used were correlated with the changes in the surface characteristics found following DBD treatments of various durations in a nitrogen atmosphere. The work focuses on the control of the gaseous environment supporting the discharge and on the possibility of overcoming the potentially dominant effect of reactive oxygen-related species, derived from any residual air present. The results obtained underline the very high reactivity of such species in the discharge, but are encouraging in respect of the possibility of the implantation or generation of functional groups other than oxygen-related ones at the surface of interest. The processing conditions concerned simulate 'real' continuous high speed processing, allowing the planning of further experiments, where various gaseous mixtures of the type X + N 2 will be used for controlled surface functionalization

  1. Cleaning of magnetic nanoparticle surfaces via cold plasmas treatments

    Directory of Open Access Journals (Sweden)

    Narayan Poudyal

    2017-05-01

    Full Text Available We report surface cleaning of magnetic nanoparticles (SmCo5 nanochips and CoFe2O4 nanoparticles by using cold plasma. SmCo5 nanochips and CoFe2O4 nanoparticles, coated with surfactants (oleic acid and oleylamine, respectively on their surfaces, were treated in cold plasmas generated in argon, hydrogen or oxygen atmospheres. The plasmas were generated using a capacitively coupled pulsed radio frequency discharge. Surface cleaning of nanoparticles was monitored by measurement of the reduction of surface carbon content as functions of plasma processing parameters and treatment times. EDX and XPS analyses of the nanoparticles, obtained after the plasma treatment, revealed significant reduction of carbon content was achieved via plasma treatment. The SmCo5 nanochips and CoFe2O4 nanoparticles treated in an argon plasma revealed reduction of atomic carbon content by more than 54 and 40 in atomic percentage, compared with the untreated nanoparticles while the morphology, crystal structures and magnetic properties are retained upon the treatments.

  2. Inverse calculation of power density for laser surface treatment

    NARCIS (Netherlands)

    Römer, Gerardus Richardus, Bernardus, Engelina; Meijer, J.

    2000-01-01

    Laser beam surface treatment requires a well-defined temperature profile. In this paper an analytic method is presented to solve the inverse problem of heat conduction in solids, based on the 2-dimensional Fourier transform. As a result, the required power density profile of the laser beam can be

  3. Influence of argon plasma treatment on polyethersulphone surface

    Indian Academy of Sciences (India)

    2013-01-09

    Jan 9, 2013 ... waste water treatment from heavy and toxic metals, low-level nuclear waste management and separation of Zr from uranium in their wastes and enzyme immobilization. The aim of this work is to improve superficial hydrophilic properties of PES films by measuring contact angle (surface free energy, SFE), ...

  4. Surface adsorption technique for the treatment of textile wastewaters ...

    African Journals Online (AJOL)

    Reductions in color and pH variation of the effluent were monitored through absorbance and pH measurements throughout the process. Concentration levels of Ni2+ in the wastewater ranged ... for treated samples to be employed for domestic purposes. Key Words: Effluents Treatment, Nickel, Chromium, Surface adsorption ...

  5. Kinetics of Microstructure Evolution during Gaseous Thermochemical Surface Treatment

    DEFF Research Database (Denmark)

    Somers, Marcel A.J.; Christiansen, Thomas

    2005-01-01

    ) precipitation of alloying element nitrides/carbides or by the development of a continuous layer of iron-based (carbo-) nitrides. The evolution of the microstructure during thermochemical treatments is not only determined by solid state diffusion, but in many cases also by the kinetics of the surface reactions...

  6. Surface treatments for material protection in nuclear power plants

    International Nuclear Information System (INIS)

    De, P.K.; Gadiyar, H.S.

    1987-01-01

    The paper highlights some of the surface treatment methods used in nuclear power plants to improve their performance. The corrosion resistance of zirconium alloys results from the formation of an adherent and protective film of ZrO 2 . Graphite coating of zircaloy-2 cladding minimizes the susceptibility to environmental induced cracking. Magnetite formation during the hot conditioning operation improves the corrosion resistance of carbon steel as well as controls the spread of radioactivity. It has been illustrated how the surface treatment is helpful for redistributing residual stress to facilitate conversion of tensile stress to compressive stress to mitigate failures due to stress corrosion and fatigue corrosion. Inhibitors and passivators can modify the surface conditions (in situ) of condenser tubes and cooling water systems. These aspects have been dealt in the text of the paper. (author). 8 refs., 3 figures

  7. Effect of Surface Treatment on the Properties of Wool Fabric

    Science.gov (United States)

    Kan, C. W.; Yuen, C. W. M.; Chan, C. K.; Lau, M. P.

    Wool fiber is commonly used in textile industry, however, it has some technical problems which affect the quality and performance of the finished products such as felting shrinkage, handle, lustre, pilling, and dyeability. These problems may be attributed mainly in the presence of wool scales on the fiber surface. Recently, chemical treatments such as oxidation and reduction are the commonly used descaling methods in the industry. However, as a result of the pollution caused by various chemical treatments, physical treatment such as low temperature plasma (LTP) treatment has been introduced recently because it is similarly capable of achieving a comparable descaling effect. Most of the discussions on the applications of LTP treatment on wool fiber were focused on applying this technique for improving the surface wettability and shrink resistance. Meanwhile, little discussion has been made on the mechanical properties, thermal properties, and the air permeability. In this paper, wool fabric was treated with LTP treatment with the use of a non-polymerizing gas, namely oxygen. After the LTP treatment, the fabrics low-stress mechanical properties, air permeability, and thermal properties were evaluated and discussed.

  8. Surface Treatment of PET Nonwovens with Atmospheric Plasma

    International Nuclear Information System (INIS)

    Li Shufang

    2013-01-01

    In this study, polyethylene-terephthalate (PET) nonwovens are treated using an atmospheric plasma and the effects of the treatment time, treatment power and discharge distance on the ability of water-penetration into the nonwovens are investigated. The result indicates that the method can improve the wettability of PET nonwovens remarkably, but the aging decay of the sample's wettability is found to be notable as a function of the storage time after treatment due to the internal rotation of the single bond of surface macromolecules. As shown by SEM and XPS analysis, the etching and surface reaction are significant, and water-penetration weight is found to increase remarkably with the increasing power. This variation can be attributed to momentum transfer and enhanced higher-energy particle excitation.

  9. Surface treatment of zinc coatings by molybdate solutions

    International Nuclear Information System (INIS)

    Fachikov, L.; Ivanova, D.

    2012-01-01

    Highlights: ► Molybdate conversion treatments on zinc coatings. ► Zn, Mo, P, O and Ni are basic elements in the coatings. ► Better corrosion resistance of zinc coatings after molybdate surface treatment. - Abstract: The influence of different factors such as concentration, temperature, pH and cathodic polarization on formation, properties and composition of coatings obtained under treatment of zinc surfaces by molybdate solutions has been investigated by gravimetric, electrochemical and physical methods. Coatings obtained at pH 4 are distinguished for the best uniformity and density of color. The thicknesses of coatings raise by increasing the cathode current density under other equal conditions. Molybdenum, zinc and phosphorus are the basic components of the passive films.

  10. An alternative treatment of occlusal wear: cast metal occlusal surface.

    Science.gov (United States)

    Kumar, Sandeep; Arora, Aman; Yadav, Reena

    2012-01-01

    Acrylic resin denture teeth often exhibit rapid occlusal wear, which may lead to decrease in the chewing efficiency, loss of vertical dimension of occlusion, denture instability, temporomandibular joint disturbances, etc. There are various treatment options available like, use of highly cross linked acrylic teeth, amalgam or metal inserts on occlusal surface, use of composite, gold or metal occlusal surface, etc. Several articles have described methods to construct gold and metal occlusal surfaces, however, these methods are time-consuming, expensive and requires many cumbersome steps. These methods also requires the patient to be without the prosthesis for the time during which the laboratory procedures are performed. This article presents a quick, simple and relatively inexpensive procedure for construction of metal occlusal surfaces on complete dentures.

  11. An alternative treatment of occlusal wear: Cast metal occlusal surface

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar

    2012-01-01

    Full Text Available Acrylic resin denture teeth often exhibit rapid occlusal wear, which may lead to decrease in the chewing efficiency, loss of vertical dimension of occlusion, denture instability, temporomandibular joint disturbances, etc. There are various treatment options available like, use of highly cross linked acrylic teeth, amalgam or metal inserts on occlusal surface, use of composite, gold or metal occlusal surface, etc. Several articles have described methods to construct gold and metal occlusal surfaces, however, these methods are time-consuming, expensive and requires many cumbersome steps. These methods also requires the patient to be without the prosthesis for the time during which the laboratory procedures are performed. This article presents a quick, simple and relatively inexpensive procedure for construction of metal occlusal surfaces on complete dentures.

  12. Investigation on Using SBS and Active Carbon Filler to Reduce the VOC Emission from Bituminous Materials

    Directory of Open Access Journals (Sweden)

    Peiqiang Cui

    2014-08-01

    Full Text Available Bituminous materials are playing a vital role in pavement design and the roofing industry because of outstanding properties. Unfortunately, bituminous materials will release volatile organic compounds (VOC, making them non-environmentally friendly. Therefore, technologies that can be used to decrease the VOC emission are urgently required. In this research, the VOC emission and material behaviors were analyzed and compared to investigate the possibility of adding styrene butadiene styrene (SBS and active carbon filler into bituminous materials to develop environmentally-friendly materials. Thermal gravimetric analysis-mass spectrometry (TG-MS and ultraviolet-visible spectroscopy testing (UV-Vis were employed to characterize the VOC emission process. Temperature sweep testing and frequency sweep testing were conducted to evaluate the rheological properties of bituminous materials. Research results indicated that the combined introduction of 4 wt% styrene butadiene styrene (SBS and 4 wt% active carbon filler cannot only significantly lower the VOC emission speed and amount, but also improve the deformation resistance behavior at a higher temperature. SBS and active carbon filler can be used to reduce the VOC emission form bituminous materials.

  13. Investigation on Using SBS and Active Carbon Filler to Reduce the VOC Emission from Bituminous Materials.

    Science.gov (United States)

    Cui, Peiqiang; Wu, Shaopeng; Li, Fuzhou; Xiao, Yue; Zhang, Honghua

    2014-08-26

    Bituminous materials are playing a vital role in pavement design and the roofing industry because of outstanding properties. Unfortunately, bituminous materials will release volatile organic compounds (VOC), making them non-environmentally friendly. Therefore, technologies that can be used to decrease the VOC emission are urgently required. In this research, the VOC emission and material behaviors were analyzed and compared to investigate the possibility of adding styrene butadiene styrene (SBS) and active carbon filler into bituminous materials to develop environmentally-friendly materials. Thermal gravimetric analysis-mass spectrometry (TG-MS) and ultraviolet-visible spectroscopy testing (UV-Vis) were employed to characterize the VOC emission process. Temperature sweep testing and frequency sweep testing were conducted to evaluate the rheological properties of bituminous materials. Research results indicated that the combined introduction of 4 wt% styrene butadiene styrene (SBS) and 4 wt% active carbon filler cannot only significantly lower the VOC emission speed and amount, but also improve the deformation resistance behavior at a higher temperature. SBS and active carbon filler can be used to reduce the VOC emission form bituminous materials.

  14. Leaching behavior of a simulated bituminized radioactive waste form under deep geological conditions

    International Nuclear Information System (INIS)

    Nakayama, Shinichi; Iida, Yoshihisa; Nagano, Tetsushi; Akimoto, Toshiyuki

    2003-01-01

    The leaching behavior of a simulated bituminized waste form was studied to acquire data for the performance assessment of the geologic disposal of bituminized radioactive waste. Laboratory-scale leaching tests were performed for radioactive and non-radioactive waste specimens simulating bituminized waste of a French reprocessing company, COGEMA. The simulated waste was contacted with deionized water, an alkaline solution (0.03-mol/l KOH), and a saline solution (0.5-mol/l KCl) under atmospheric and anoxic conditions. The concentrations of Na, Ba, Cs, Sr, Np, Pu, NO 3 , SO 4 and I in the leachates were determined. Swelling of the bituminized waste progressed in deionized water and KOH. The release of the soluble components, Na and Cs, was enhanced by the swelling, and considered to be diffusion-controlled in the swelled layers of the specimens. The release of sparingly soluble components such as Ba and Np was solubility-limited in addition to the progression of leaching. Neptunium, a redox-sensitive element, showed a distinct difference in release between anoxic and atmospheric conditions. The elemental release from the bituminized waste specimens leached in the KCl was very low, which is likely due to the suppression of swelling of the specimens at high ionic strength. (author)

  15. Effects of Surface Treatment of Activated Carbon on Its Surface and Cr(VI) Adsorption Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soo Jin; Jang, Yu Sin [Advanced Materials Division., Korea Research Institute of Chimical Technology, Taejon (Korea)

    2001-04-01

    In this work, the effect of surface treatments on activated carbons (ACs) has been studied in the context of gas and liquid adsorption behaviors. The chemical solutions used in this experiment were 35% sodium hydroxide, and these were used for the acidic and basic treatments, respectively. The surface properties have been determined by pH, acid-base values, and FT-IR. The adsorption isotherms of Cr(VI) ion on activated carbons have been studied with the 5 mg/l concentration at ambient temperature. N{sub 2} adsorption isotherm characteristics, which include the specific surface area, micro pore volume, and microporosity, were determined by BET and Boer's-plot methods. In case of the acidic treatment of activated carbons, it was observed that the adsorption of Cr(VI) ion was more effective due to the increase acid value (or acidic functional group) of activated carbon surfaces. However, the basic treatment on activated carbons was caused no significant effects, probably due to the decreased specific surface area and total pore volume. 27 refs., 7 figs., 4 tabs.

  16. Comprehensive surface treatment of high-speed steel tool

    Science.gov (United States)

    Fedorov, Sergey V.; Aleshin, Sergey V.; Swe, Min Htet; Abdirova, Raushan D.; Kapitanov, Alexey V.; Egorov, Sergey B.

    2018-03-01

    One of the promising directions of hardening of high-speed steel tool is the creation on their surface of the layered structures with the gradient of physic-chemical properties between the wear-resistant coatings to the base material. Among the methods of such surface modification, a special process takes place based on the use of pulsed high-intensity charged particle beams. The high speed of heating and cooling allows structural-phase transformations in the surface layer, which cannot be realized in a stationary mode. The treatment was conducted in a RITM-SP unit, which constitutes a combination of a source of low-energy high-current electron beams "RITM" and two magnetron spraying systems on a single vacuum chamber. The unit enables deposition of films on the surface of the desired product and subsequent liquid-phase mixing of materials of the film and the substrate by an intense pulse electron beam. The article discusses features of the structure of the subsurface layer of high-speed steel M2, modified by surface alloying of a low-energy high-current electron beam, and its effect on the wear resistance of the tool when dry cutting hard to machine Nickel alloy. A significant decrease of intensity of wear of high-speed steel with combined treatment happens due to the displacement of the zone of wear and decrease the radius of rounding of the cutting edge because of changes in conditions of interaction with the material being treated.

  17. ELECTROLYTIC-PLASMA TREATMENT OF INNER SURFACE OF TUBULAR PRODUCTS

    Directory of Open Access Journals (Sweden)

    Yu. G. Alekseev

    2016-01-01

    Full Text Available While manufacturing a number of important tubular products stringent requirements have been imposed on quality of their inner surfaces. The well-known methods for inner surface treatment of pipes include sandblasting, chemical cleaning with acid reagents (oxalic, formic, sulfamic, orthophosphoric acids and electrochemical polishing. Disadvantages of the chemical method are cleaning-up irregularities, high metal removal, limited number of reagent application, complicated selection of reagent chemical composition and concentration, complicated and environmentally harmful recycling of waste chemicals, high cost of reagents. Low productivity at a high cost, as well as hazardous impact on personnel due to high dispersion of abrasive dust are considered as disadvantages of sandblasting. Electrochemical polishing is characterized by the following disadvantages: low processing productivity because supply of high currents is rather difficult due to electrolyte scattering capacity away from the main electrode action zone, limited length of the cavity to be treated due to heating of flexible current leads at operating current densities, application of expensive aggressive electrolytes and high costs of their recycling. A new method for polishing and cleaning of inner surfaces of tubular products based on electrolyte-plasma treatment has been developed. In comparison with the existing methods the proposed methods ensures quality processing with high intensity while applying non-toxic, environmentally friendly and cheap electrolytes. The paper presents results of investigations on technological specific features of electrolyte-plasma treatment for inner surfaces of tubular products: influence of slotted nozzle width, electrolyte flow and rate on stability of gas-vapor blanket, current density and productivity. Results of the research have made it possible to determine modes that provide stability and high productivity in the process of electrolyte

  18. Durability assessment of limestone subjected to surface treatments

    Science.gov (United States)

    Theodoridou, Magdalini; Charalambous, Cleopatra; Ioannou, Ioannis

    2017-04-01

    Weathering is inevitable in existing limestone structures due to their exposure to fluctuating and aggressive environmental conditions, such as wetting/drying, and the presence of salts. Therefore, conservation treatments are often deemed necessary in order to prevent or at least delay the progress of deterioration and to strengthen weathered stones. This paper focuses on the effect of an ethanol-based laboratory produced water repellent and three water-based commercial products (water repellent, pure acrylic emulsion mixed with a water repellent with thermal insulation properties and consolidant) on the durability and other properties of three different types of limestone (massive chalk, calcarenite and bioclastic limestone). All test specimens were subjected to micro-destructive cutting tests before/after the application of the aforementioned surface treatments to investigate changes in resistance to cutting on the area close to the treated surface. They were also subjected to two cycles of salt contamination with 20% w/w Na2SO4•10H2O solution by capillary absorption through their bottom face, until 2 mm of pore space was theoretically filled with salt crystals. Drying after salt contamination took place at 70 °C. The results of the micro-destructive cutting tests showed increases in cutting resistance at the topmost area (1-2 mm below the treated surface) of the massive chalk and the calcarenite, but no significant changes in the case of the rather non-homogeneous bioclastic limestone. At the same time, the performance of each surface treatment varied from lithotype to lithotype. The laboratory produced water repellent showed a generally better performance; no signs of damage were detected due to the formation of salt crystals within the pores of the materials, i.e. subflorescence, when applied on the calcarenite and the bioclastic limestone. Very poor performance was observed for all treatments when applied on the massive chalk. This accounted for (i

  19. Kinetics of Microstructure Evolution during Gaseous Thermochecical Surface Treatment

    DEFF Research Database (Denmark)

    Somers, Marcel A.J.; Christiansen, Thomas

    2005-01-01

    The incorporation of nitrogen or carbon in steel is widely applied to provide major improvements in-materials performance with respect to fatigue, weaif tribology, and atmospheric corrosion. These improvements rely on a modification of the surface-adjacent region of the materiat by tl.re (internalf...... precipitation 6f ailoying element nitrides/carbides"or by thE development of a continuo_us laye_r of iron-based (carbo-) nitrides. The evolution of the microstructure during thermochemical treatme_nts is not only determined by solid-state diffusion, but in many cases also by the kinetics of the surface...

  20. Protective coatings of metal surfaces by cold plasma treatment

    Science.gov (United States)

    Manory, R.; Grill, A.

    1985-01-01

    The cold plasma techniques for deposition of various types of protective coatings are reviewed. The main advantage of these techniques for deposition of ceramic films is the lower process temperature, which enables heat treating of the metal prior to deposition. In the field of surface hardening of steel, significant reduction of treatment time and energy consumption were obtained. A simple model for the plasma - surface reactions in a cold plasma system is presented, and the plasma deposition techniques are discussed in view of this model.

  1. Global market trade policy analysis for petroleum oils and oils obtained from bituminous minerals, crude

    Directory of Open Access Journals (Sweden)

    Bagheri, F.

    2012-01-01

    Full Text Available This article is based on surveying the custom tariffs imposed on the world export market of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. We obtained the data according to the most updated available data provided online by UNCTAD and World Bank. The results indicate that none of the 142 countries in the world market of this product have imposed non-tariff trade barriers on the import of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. The developed countries and the countries with transition economies are the main world import partners. European Union, United States, China, Japan, South Korea, Canada, Singapore, Taiwan, Thailand, South Africa, Australia, Turkey, Brazil, Sweden and Belarus are the examples and have imposed low custom tariffs on Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude.

  2. Study on the coprocessing of Xingiang Heishan bituminous coal with Tahe petroleum residue

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, C.; Zhao, P.; Li, K. [China Shenhua Coal to Liquefaction Corporation Ltd., Ordo (China)

    2007-02-15

    The reaction process of coprocessing Xinjiang Heishan bituminous coal and petroleum residue from Tahe petroleum chemical corporation was studied by using a Japanese vibrating horizontal autoclave. The effects of different petroleum residual addition on coal liquefaction was investigated and compared with the liquefaction result under the condition of exclusive Heishan bituminous coal. The results show that compared with the liquefaction results with only Heishan bituminous coal, coal-residual coprocessing has the characteristics of low hydrogen consumption, low gas and high oil yield. Coal conversion and oil yield was increased with proper addition of petroleum residues. In this experimental system, the optimum addition of petroleum residue is 20%. Coal conversion and oil yield are increased by 1.5% and 11% respectively. 2 refs., 1 fig., 5 tabs.

  3. Plasma Treatment Maintains Surface Energy of the Implant Surface and Enhances Osseointegration

    Directory of Open Access Journals (Sweden)

    Fernando P. S. Guastaldi

    2013-01-01

    Full Text Available The surface energy of the implant surface has an impact on osseointegration. In this study, 2 surfaces: nonwashed resorbable blasting media (NWRBM; control and Ar-based nonthermal plasma 30 days (Plasma 30 days; experimental, were investigated with a focus on the surface energy. The surface energy was characterized by the Owens-Wendt-Rabel-Kaelble method and the chemistry by X-ray photoelectron spectroscopy (XPS. Five adult beagle dogs received 8 implants (n=2 per surface, per tibia. After 2 weeks, the animals were euthanized, and half of the implants (n=20 were removal torqued and the other half were histologically processed (n=20. The bone-to-implant contact (BIC and bone area fraction occupancy (BAFO were evaluated on the histologic sections. The XPS analysis showed peaks of C, Ca, O, and P for the control and experimental surfaces. While no significant difference was observed for BIC parameter (P>0.75, a higher level for torque (P<0.02 and BAFO parameter (P<0.01 was observed for the experimental group. The surface elemental chemistry was modified by the plasma and lasted for 30 days after treatment resulting in improved biomechanical fixation and bone formation at 2 weeks compared to the control group.

  4. Superhydrophobic NiTi shape memory alloy surfaces fabricated by anodization and surface mechanical attrition treatment

    Science.gov (United States)

    Ou, Shih-Fu; Wang, Kuang-Kuo; Hsu, Yen-Chi

    2017-12-01

    This paper describes the fabrication of superhydrophobic NiTi shape memory alloy (SMA) surfaces using an environmentally friendly method based on an economical anodizing process. Perfluorooctyltriethoxysilane was used to reduce the surface energy of the anodized surfaces. The wettability, morphology, composition, and microstructure of the surfaces were investigated by scanning electron microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy. The surface of the treated NiTi SMA exhibited superhydrophobicity, with a water contact angle of 150.6° and sliding angle of 8°. The anodic film on the NiTi SMA comprised of TiO2 and NiO, as well as traces of TiCl3. In addition, before the NiTi SMA was anodized, it underwent a surface mechanical attrition treatment to grain-refine its surface. This method efficiently enhanced the growth rate of the anodic oxide film, and improved the hydrophobic uniformity of the anodized NiTi-SMA-surface.

  5. Surface roughness and the flexural and bend strength of zirconia after different surface treatments.

    Science.gov (United States)

    Hjerppe, Jenni; Närhi, Timo O; Vallittu, Pekka K; Lassila, Lippo V J

    2016-10-01

    Different surface treatments are commonly used during the fabrication of zirconia fixed dental prostheses. However, such treatments can affect the properties of the zirconia framework material. The purpose of this in vitro study was to determine the effect of different surface treatments on the surface roughness and flexural and bend strength of zirconia. Seventy-two zirconia disks (n=8) and 72 zirconia bars (n=8) were sintered and divided into 9 groups for different surface treatments: sintered control, airborne-particle abraded with 50-μm aluminum oxide, airborne-particle abraded with Rocatec soft (30 μm), airborne-particle abraded with Rocatec (105 μm), grinding dry with a micromotor, turbine grinding under water cooling, grinding with silicon carbide paper, diamond paste polishing, and steam cleaning. The biaxial flexural strength of the disks (diameter 19 mm, thickness 1.6 mm) and 3-point bend test of the bars (thickness 2 mm, height 2 mm, length 25 mm) were measured dry at room temperature. One-way ANOVA followed by the Tukey HSD test (α=.05) and Pearson correlation test were used for statistical analysis. Airborne-particle abrasion and silicon carbide paper grinding increased the flexural and bend strength of zirconia specimens (Pzirconia framework material. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  6. Evaluation of Cellulosic Fabrics Surface Characteristics after Different Treatments

    Directory of Open Access Journals (Sweden)

    Vitalija MASTEIKAITĖ

    2014-09-01

    Full Text Available Various clothes treatments during their manufacture and wear change the fabrics physical and surface characteristics. The different testing methods for fabrics quality evaluation are used in this research. The aim of this work is to examine the effect of enzyme treatment, laundering and abrasion on the appearance of different cellulosic fabrics. Six cotton and cotton blend woven fabrics used for faded garments production were chosen for this examination. Treatments such, as enzyme wash, domestic laundering, abrasion using IT-2 and Martindale (Mesdan instruments and rubbing were applied in order to evaluate the worn look of the different fabrics. The degree of fabrics distortion was determined by using abrasion resistance and weight change characteristics. Also, the colour fastness and staining after different dry and wet treatments were analysed. The results of this research show that the surface characteristics of cellulosic fabrics depend on the properties of the fabrics and the type of treatment. Most of the tested cellulosic fabrics have changed their difference in colour not only after the enzyme wash but also after successive abrading and cyclical domestic launderings. Both colour fading of the fabrics and staining of cotton white fabric may appear after rubbing in dry and especially in wet conditions. The received results show that during tested fabrics laundering, the cotton and nylon parts of multifibre fabric were stained more heavily. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4331

  7. Effect of different surface treatments on bond strength, surface and microscopic structure of zirconia ceramic

    Directory of Open Access Journals (Sweden)

    Zeinab R. El-Shrkawy

    2016-06-01

    Conclusions: (1 Surface treatments of Y-TZP ceramic together with MDP primer and silane-coupling agent application improve the bond strength to resin cement. (2 Plasma-Silica coating and plasma-oxygen treatment, both are valuable methods that improve the bond strength of resin cement to Y-TZP ceramic. (3 Silica coating by plasma technology provides durable bond strength and can be a promising alternative pretreatment before silane application to enhance bonding with zirconia ceramic. (4 Tetragonal-monoclinic phase transformation had occurred in Y-TZP samples received both types of plasma treatment.

  8. Surface treatments for biological, chemical and physical applications

    CERN Document Server

    Karaman, Mustafa

    2017-01-01

    A step-by-step guide to the topic with a mix of theory and practice in the fields of biology, chemistry and physics. Straightforward and well-structured, the first chapter introduces fundamental aspects of surface treatments, after which examples from nature are given. Subsequent chapters discuss various methods to surface modification, including chemical and physical approaches, followed by the characterization of the functionalized surfaces. Applications discussed include the lotus effect, diffusion barriers, enzyme immobilization and catalysis. Finally, the book concludes with a look at future technology advances. Throughout the text, tutorials and case studies are used for training purposes to grant a deeper understanding of the topic, resulting in an essential reference for students as well as for experienced engineers in R&D.

  9. Effect of alkali treatment on surface morphology of titanium

    Energy Technology Data Exchange (ETDEWEB)

    Tan, K. J., E-mail: gd130056@siswa.uthm.edu.my; Wahab, M. A. A., E-mail: cd110006@siswa.uthm.edu.my; Mahmod, S., E-mail: cd110201@siswa.uthm.edu.my; Idris, M. I., E-mail: izwana@uthm.edu.my; Abdullah, H. Z., E-mail: hasan@uthm.edu.my [Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Parit Raja, Batu Pahat, Johor (Malaysia)

    2015-07-22

    Alkali and heat treatments were first introduced by Kim et al. to prepare a bioactive surface on titanium. This method has been proven very effective and widely used in other studies to promote titanium osteointegration. This study aims to investigate further the effect of alkali treatment on surface morphology of high purity titanium. High purity titanium foils were immersed in NaOH aqueous solutions of 0.5 M, 5 M and 15 M at 60°C and 80 °C for 1, 3 and 7 days. The surface morphology was examined using Field Emission Scanning Electron Microscope (FESEM). The obtained phases were analysed using Fourier Transform Infrared Spectroscopy (FTIR) in the spectra range of 4000-600 cm{sup −1} at 4 cm{sup −1} resolution and 50 scans. At the same soaking temperature and soaking time, a thicker porous network was observed with increasing concentration of NaOH. At the same soaking temperature, a much porous structure was observed with increasing soaking time. At constant alkali concentration, more homogenously distributed porous surface structure was observed with increasing soaking temperature.

  10. Diffuse coplanar surface barrier discharge -- basic properties and its application in surface treatment of nonwovens

    Science.gov (United States)

    Kovacik, Dusan; Rahel, Jozef; Kubincova, Jana; Zahoranova, Anna; Cernak, Mirko

    2009-10-01

    In recent years, low temperature atmospheric pressure plasma surface treatments have become a hot topic because of the potential of fast and efficient in-line processing fabrication without expensive vacuum equipment. A major problem of atmospheric pressure treatment in air is insufficient treatment uniformity because, particularly at the higher plasma power densities, the air plasma has the tendency of filamentation and transition into an arc discharge. Diffuse coplanar surface barrier discharge (DCSBD) plasma source has been developed to overcome these problems. This type of discharge enables to generate macroscopically homogeneous thin (˜ 0.3 mm) plasma layer with power density of some 100 W/cm^3 practically in any gas without admixture of He. It was found that the ambient air plasma of DCSBD is capable to make lightweight polypropylene nonwoven fabrics permanently hydrophilic, without any pinholing and with low power consumption of some 1 kWh/kg.

  11. Estimated Valuation of the Cost of Road Construction with the Use of Composite Cationic Bituminous Structures

    Directory of Open Access Journals (Sweden)

    Vorotynseva Anna

    2017-01-01

    Full Text Available The need for formation of prices for road construction works producing, by using composite of cationic bituminous structures, is dictated by absence of this type of work in estimate-normative base, due to the fact that this type of materials had never been used before. Estimated specifications could be used either for determination of work cost or for substantiation of efficiency of using new type of materials. This paper provides basic concepts, related to formation of estimate-normative base for determination of construction and installation works cost, particularly road construction works, also it shows formation of coating installation prices by using composite of cationic bituminous emulsions.

  12. Dental Hetero-Graft Materials with Nano Hydroxyapatite Surface Treatment.

    Science.gov (United States)

    Kim, Dai-Hwan; Kim, Kyung-Il; Yoon, Seokyoung; Kim, Hyung-Jo; Ahn, Jin-Soo; Jun, Sang Ho; Kang, Ho Chang; Pang, Changhyun; Kim, Jaeyun; Cha, Hyung Joon; Han, Kwon-Hoon; Kim, Dong-Myong; Lee, Jung Heon

    2015-10-01

    We report the development of hydroxyapatite nanoparticle (HAp NP)-functionalized hetero-graft materials (HGMs) for dental applications. These HGMs were prepared by attaching platelet-, needle-, and sphere-shaped HAp NPs to the surface of xenograft materials through chemical conjugation. Although all three HAp NPs contributed to increase the surface area of bone graft material (BGM), the shape of the HAp NPs was a determining factor. Platelet HAp NPs were most effective, because they caused a 48.9% increase in BGM surface area whereas the influence of the spherical NP was only a 6.7% increase. This suggests that geometric factors regarding both the attached HAp NPs and graft material surface are essential in controlling the surface roughness of graft materials. Among the three HAp NPs, it was the platelet HAp NPs that helped to increase the efficacy of the BGM most significantly. Compared with BGM with no HAp NP attachment, HGM with platelet HAp NP ('platelet-HGM) treatment had ~46.1% higher cell attachment and proliferation rate. The MTT assay also showed that the HAp NP-treated hetero-graft materials had negligible cytotoxicity.

  13. Work function modifications of graphite surface via oxygen plasma treatment

    Science.gov (United States)

    Duch, J.; Kubisiak, P.; Adolfsson, K. H.; Hakkarainen, M.; Golda-Cepa, M.; Kotarba, A.

    2017-10-01

    The surface modification of graphite by oxygen plasma was investigated experimentally (X-ray diffraction, nanoparticle tracking analysis, laser desorption ionization mass spectrometry, thermogravimetry, water contact angle) and by molecular modelling (Density Functional Theory). Generation of surface functional groups (mainly sbnd OHsurf) leads to substantial changes in electrodonor properties and wettability gauged by work function and water contact angle, respectively. The invoked modifications were analyzed in terms of Helmholtz model taking into account the theoretically determined surface dipole moment of graphite-OHsurf system (μ = 2.71 D) and experimentally measured work function increase (from 0.75 to 1.02 eV) to determine the sbnd OH surface coverage (from 0.70 to 1.03 × 1014 groups cm-2). Since the plasma treatment was confined to the surface, the high thermal stability of the graphite material was preserved as revealed by the thermogravimetric analysis. The obtained results provide a suitable quantitative background for tuning the key operating parameters of carbon electrodes: electronic properties, interaction with water and thermal stability.

  14. Corrosion protection of aluminum by silane-based surface treatment

    Science.gov (United States)

    Song, Jun

    The possibility of using silane coupling agents as replacements for chromate treatments was investigated for aluminum substrates. In order to understand the influence of deposition parameters on silane film formation, pure Al substrates were used to study the interaction between silane coupling agents and aluminum surfaces. The silane films formed on pure A1 substrates from aqueous solutions were characterized by ellipsometry, contact angle measurements, reflection absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and Time-of Flight Secondary Ion Mass Spectrometry. The deposition parameters studied include solution concentration, solution dipping time and pH value of the applied solution. It appears that silane film formation involved a true equilibrium of hydrolysis and condensation in aqueous solution. It has been found that the silane film thickness obtained depends primarily on the solution concentration and is independent of the solution dipping time. The molecular orientation of the applied silane film is determined by the pH value of the applied silane solution and the isoelectic point of the metal substrates. The deposition window in terms of pH value for A1 substrates is between 4 and 7. The total surface energy of silane-coated A1 substrate decreases with film aging time, the decreased rate, however, is determined by the nature of silane coupling agents. Based on the results obtained above, a pretreatment, which involved two-step bis-(triethoxysilyl) ethane and gamma-aminopropyltriethoxysilane, was developed for Al substrates with commercial polyester and polyurethane paints. The results of salt spray testing, cyclic corrosion testing, and electrochemical impedance spectroscopy showed that this treatment provided the same level of corrosion performance as the treatment of phosphating plus a final chromate rinse. The likely reasons for excellent performance are discussed in terms of the physical and chemical characteristics of the

  15. Altering surface characteristics of polypropylene mesh via sodium hydroxide treatment.

    Science.gov (United States)

    Regis, Shawn; Jassal, Manisha; Mukherjee, Nilay; Bayon, Yves; Scarborough, Nelson; Bhowmick, Sankha

    2012-05-01

    Incisional hernias represent a serious and common complication following laparotomy. The use of synthetic (e.g. polypropylene) meshes to aid repair of these hernias has considerably reduced recurrence rates. While polypropylene is biocompatible and has a long successful clinical history in treating hernias and preventing reherniation, this material may suffer some limitations, particularly in challenging patients at risk of wound failure due to, for example, an exaggerated inflammation reaction, delayed wound healing, and infection. Surface modification of the polypropylene mesh without sacrificing its mechanical properties, critical for hernia repair, represents one way to begin to address these clinical complications. Our hypothesis is treatment of a proprietary polypropylene mesh with sodium hydroxide (NaOH) will increase in vitro NIH/3T3 cell attachment, predictive of earlier and improved cell colonization and tissue integration of polypropylene materials. Our goal is to achieve this altered surface functionality via enhanced removal of chemicals/oils used during material synthesis without compromising the mechanical properties of the mesh. We found that NaOH treatment does not appear to compromise the mechanical strength of the material, despite roughly a 10% decrease in fiber diameter. The treatment increases in vitro NIH/3T3 cell attachment within the first 72 h and this effect is sustained up to 7 days in vitro. This research demonstrates that sodium hydroxide treatment is an efficient way to modify the surface of polypropylene hernia meshes without losing the mechanical integrity of the material. This simple procedure could also allow the attachment of a variety of biomolecules to the polypropylene mesh that may aid in reducing the complications associated with polypropylene meshes today. Copyright © 2012 Wiley Periodicals, Inc.

  16. Application of an Ecological Surface Treatment for Aluminum Profile

    Directory of Open Access Journals (Sweden)

    Brenda Luisa McNeil-Montañes

    2015-11-01

    Full Text Available Once aluminium is extruded, in contact with oxygen, forms quickly an aluminium oxide superficial protector layer, which is not penetrated  by humidity, gases or polluting agents. This layer has a low thickness and is a bad base for painting anchorage. Through the chemical superficial treatment of the aluminium profile (degreased, deoxidized and cleaning, it is possible its preparation to el iminate the thin oxide superficial layer and dirty and to form a layer of better features. This process is carried out submerging the profiles in the sour dissolution and in the cleaning dissolution (water from the aqueduct and also treated water, without  ions to leave them clean and lastly it is carried out the surface passivation treatment, also called chemical conversion treatment, to obtain bigger penetration and stability of the paintings. The lacquered plant of aluminium, Lacalum, which is the only o ne of this type in the country, used to employ and old technology of chemical superficial treatment using watery solutions that contained hexavalents chromium ions, in order to form a protector layer on the aluminium profiles. This chemical treatment is very harmful to health, that why it was decided its substitution for a new advanced and respectful with the environment technology of non-chromium treatment; as well as the installation of a treatment plant for the process residuals. In general, these improv ements allow obtaining a better product with the smallest impact to the environment as possible, and better in social aspect, thanks to the humanization of the work, and also in economic aspect, because of the decrease of the production costs. In this work, specifications, that most be considered during this non -chromium superficial chemical treatment of the aluminium profiles, are given to obtain a later lacquered; as well as the improvements for the environment.

  17. Catalytic Two-Stage Liquefaction (CTSL{trademark}) process bench studies and PDU scale-up with sub-bituminous coal. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Johanson, E.S.; Karolkiewicz, W.F.; Lee, L.K.T.; Stalzer, R.H.; Smith, T.O.

    1993-03-01

    Reported are the details and results of Laboratory and Bench-Scale experiments using sub-bituminous coal conducted at Hydrocarbon Research, Inc., under DOE Contract No. DE-AC22-88PC88818 during the period October 1, 1988 to December 31, 1992. The work described is primarily concerned with testing of the baseline Catalytic Two-Stage Liquefaction (CTSL{trademark}) process with comparisons with other two stage process configurations, catalyst evaluations and unit operations such as solid separation, pretreatments, on-line hydrotreating, and an examination of new concepts. In the overall program, three coals were evaluated, bituminous Illinois No. 6, Burning Star and sub-bituminous Wyoming Black Thunder and New Mexico McKinley Mine seams. The results from a total of 16 bench-scale runs are reported and analyzed in detail. The runs (experiments) concern process variables, variable reactor volumes, catalysts (both supported, dispersed and rejuvenated), coal cleaned by agglomeration, hot slurry treatments, reactor sequence, on-line hydrotreating, dispersed catalyst with pretreatment reactors and CO{sub 2}/coal effects. The tests involving the Wyoming and New Mexico Coals are reported herein, and the tests involving the Illinois coal are described in Topical Report No. 2. On a laboratory scale, microautoclave tests evaluating coal, start-up oils, catalysts, thermal treatment, CO{sub 2} addition and sulfur compound effects were conducted and reported in Topical Report No. 3. Other microautoclave tests are described in the Bench Run sections to which they refer such as: rejuvenated catalyst, coker liquids and cleaned coals. The microautoclave tests conducted for modelling the CTSL{trademark} process are described in the CTSL{trademark} Modelling section of Topical Report No. 3 under this contract.

  18. Surface-wave-sustained plasma torch for water treatment

    Science.gov (United States)

    Marinova, P.; Benova, E.; Todorova, Y.; Topalova, Y.; Yotinov, I.; Atanasova, M.; Krcma, F.

    2018-02-01

    In this study the effects of water treatment by surface-wave-sustained plasma torch at 2.45 GHz are studied. Changes in two directions are obtained: (i) changes of the plasma characteristics during the interaction with the water; (ii) water physical and chemical characteristics modification as a result of the plasma treatment. In addition, deactivation of Gram positive and Gram negative bacteria in suspension are registered. A number of charged and excited particles from the plasma interact with the water. As a result the water chemical and physical characteristics such as the water conductivity, pH, H2O2 concentration are modified. It is observed that the effect depends on the treatment time, wave power, and volume of the treated liquid. At specific discharge conditions determined by the wave power, gas flow, discharge tube radius, thickness and permittivity, the surface-wave-sustained discharge (SWD) operating at atmospheric pressure in argon is strongly non-equilibrium with electron temperature T e much higher than the temperature of the heavy particles (gas temperature T g). It has been observed that SWD argon plasma with T g close to the room temperature is able to produce H2O2 in the water with high efficiency at short exposure times (less than 60 sec). The H2O2 decomposition is strongly dependant on the temperature thus the low operating gas temperature is crucial for the H2O2 production efficiency. After scaling up the device, the observed effects can be applied for the waste water treatment in different facilities. The innovation will be useful especially for the treatment of waters and materials for medical application.

  19. SEM Analysis of Surface Impact on Biofilm Antibiotic Treatment.

    Science.gov (United States)

    Gomes, Luciana Calheiros; Mergulhão, Filipe José

    2017-01-01

    The aim of this work was to use scanning electron microscopy (SEM) to investigate the effect of ampicillin treatment on Escherichia coli biofilms formed on two surface materials with different properties, silicone (SIL) and glass (GLA). Epifluorescence microscopy (EM) was initially used to assess biofilm formation and killing efficiency on both surfaces. This technique showed that higher bacterial colonization was obtained in the hydrophobic SIL than in the hydrophilic GLA. It has also shown that higher biofilm inactivation was attained for GLA after the antibiotic treatment (7-log reduction versus 1-log reduction for SIL). Due to its high resolution and magnification, SEM enabled a more detailed analysis of the antibiotic effect on biofilm cells, complementing the killing efficiency information obtained by EM. SEM micrographs revealed that ampicillin-treated cells have an elongated form when compared to untreated cells. Additionally, it has shown that different materials induced different levels of elongation on cells exposed to antibiotic. Biofilms formed on GLA showed a 37% higher elongation than those formed on SIL. Importantly, cell elongation was related to viability since ampicillin had a higher bactericidal effect on GLA-formed biofilms. These findings raise the possibility of using SEM for understanding the efficacy of antimicrobial treatments by observation of biofilm morphology.

  20. RF atmospheric plasma jet surface treatment of paper

    Science.gov (United States)

    Pawlat, Joanna; Terebun, Piotr; Kwiatkowski, Michał; Diatczyk, Jaroslaw

    2016-09-01

    A radio frequency RF atmospheric pressure plasma jet was used to enhance the wettability of cellulose-based paper of 90 g m-2 and 160 g m-2 grammage as a perspective platform for antibiotic sensitivity tests. Helium and argon were the carrier gases for oxygen and nitrogen; pure water and rapeseed oil were used for goniometric tests. The influence of the flow rate and gas type, the power of the discharge, and distance from the nozzle was examined. The surface structure was observed using an optical microscope. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectra were investigated in order to determine whether cellulose degradation processes occurred. The RF plasma jet allowed us to decrease the surface contact angle without drastic changes in other features of the tested material. Experiments confirmed the significant influence of the distance between the treated sample and reactor nozzle, especially for treatment times longer than 15 s due to the greater concentration of reactive species at the surface of the sample, which decreases with distance—and their accumulation effect with time. The increase of discharge power plays an important role in decreasing the surface contact angle for times longer than 10 s. Higher power had a positive effect on the amount of generated active particles and facilitated the ignition of discharge. However, a too high value can cause a rise in temperature of the material and heat-caused damage.

  1. Effect of Surface Treatments on Leakage of Zirconium Oxide Ceramics

    Directory of Open Access Journals (Sweden)

    Göknil Alkan Demetoğlu

    2016-08-01

    Full Text Available Objective: The aim of this pilot study was to compare the effects of pretreatments on leakage of zirconia ceramics. Materials and Methods: The speciments divided into 6 groups that were subsequently treated as follows: group 1, no treatment (control; group 2, the ceramic surfaces were airborne-particle abraded with 110 μm aluminum-oxide (Al2O3 particles; group 3, after abrasion of the surfaces with 110 μm Al2O3 particles, silica coating using 30 μm (Al2O3 particles modified by silica (rocatec system and application of the silane coupling agent (espe-sil; group 4, ceramic surfaces irritated with neodymium-doped yttrium aluminium garnet (Nd:YAG laser [fidelis plus 3 foton (Ljubljana, Slovenia] at 20 hz, 100 mj, 2 w, 100 μs; group 5, ceramic surfaces irritated with Nd:YAG laser at fidelis plus 3 fotona (Ljubljana, Slovenia at 20 hz, 100 mj, 2 w, 100 μs; group 6; application of a zirconia primer (z-prime plus bisco, IL, USA agent. And all ceramics tested for leakage. Results: For marginal leakage, score 0 was found in all groups. Conclusion: No significant differences were found in marginal leakage under all conditions.

  2. Effect of surface mechanical attrition treatment (SMAT) on microhardness, surface roughness and wettability of AISI 316L

    NARCIS (Netherlands)

    Arifvianto, B.; Suyitno, [No Value; Mahardika, M.; Dewo, P.; Iswanto, P. T.; Salim, U. A.

    2011-01-01

    Surface roughness and wettability are among the surface properties which determine the service lifetime of materials. Mechanical treatments subjected to the surface layer of materials are often performed to obtain the desired surface properties and to enhance the mechanical strength of materials. In

  3. Microstructural self-healing of bituminous materials : Combined experimental and numerical study

    NARCIS (Netherlands)

    Pauli, A.; Schmets, A.J.M.; Kasbergen, C.; Varveri, K.; Scarpas, A.

    2013-01-01

    Bituminous materials form a class of materials that possess the intrinsic ability to selfheal. This self-healing capability is evidenced by the observation that the service life of these materials ‘in the field’ exceeds the service life as predicted by standard mechanical laboratory tests. This

  4. The X-ray fluorescent method for determination of total sulphur in bituminous coals

    International Nuclear Information System (INIS)

    Widowska-Kusmierska, J.; Siess, K.

    1979-01-01

    The X-ray fluorescent technique for the determination of total sulphur covering concentrations from 0,1 to 10% has been applied for bituminous coals showing a great variability in qualitative and quantitative composition of mineral matter (ash). The described method is a quick one giving results during one hour. The obtained good accuracy of determinations gives prospects for wide industrial application. (author)

  5. Assessment of underground coal gasification in bituminous coals. Volume I. Executive summary. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-01-01

    This report describes the bituminous coal resources of the United States, identifies those resources which are potentially amenable to Underground Coal Gasification (UCG), identifies products and markets in the vicinity of selected target areas, identifies UCG concepts, describes the state of the art of UCG in bituminous coal, and presents three R and D programs for development of the technology to the point of commercial viability. Of the 670 billion tons of bituminous coal remaining in-place as identified by the National Coal Data System, 32.2 billion tons or 4.8% of the total are potentially amenable to UCG technology. The identified amenable resource was located in ten states: Alabama, Colorado, Illinois, Kentucky, New Mexico, Ohio, Oklahoma, Utah, Virginia, and West Virginia. The principal criteria which eliminated 87.3% of the resource was the minimum thickness (42 inches). Three R and D programs were developed using three different concepts at two different sites. Open Borehole, Hydraulic Fracture, and Electrolinking concepts were developed. The total program costs for each concept were not significantly different. The study concludes that much of the historical information based on UCG in bituminous coals is not usable due to the poor siting of the early field tests and a lack of adequate diagnostic equipment. This information gap requires that much of the early work be redone in view of the much improved understanding of the role of geology and hydrology in the process and the recent development of analytical tools and methods.

  6. Effect of bituminous coal properties on carbon dioxide and methane high pressure sorption

    Czech Academy of Sciences Publication Activity Database

    Weishauptová, Zuzana; Přibyl, Oldřich; Sýkorová, Ivana; Machovič, Vladimír

    2015-01-01

    Roč. 139, JAN 1 (2015), s. 115-124 ISSN 0016-2361 Institutional support: RVO:67985891 Keywords : bituminous coal * sorption capacity * maceral composition * Upper Silesian Coal Basin Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.611, year: 2015

  7. Chemomechanics of Damage Accumulation and Damage-Recovery Healing in Bituminous Asphalt Binders

    NARCIS (Netherlands)

    Pauli, A.T.

    2014-01-01

    As a contribution to the development of mutli-scale multi-physics approaches to modelling pavement performance, the present thesis considers the topic of damage accumulation accompanied by damage recover self-healing of the bituminous asphalt phase of pavement systems. It is found insightful that by

  8. 8th RILEM International Symposium on Testing and Characterization of Sustainable and Innovative Bituminous Materials

    CERN Document Server

    Partl, Manfred

    2016-01-01

    This work presents the results of RILEM TC 237-SIB (Testing and characterization of sustainable innovative bituminous materials and systems). The papers have been selected for publication after a rigorous peer review process and will be an invaluable source to outline and clarify the main directions of present and future research and standardization for bituminous materials and pavements. The following topics are covered: - Characterization of binder-aggregate interaction - Innovative testing of bituminous binders, additives and modifiers - Durability and aging of asphalt pavements - Mixture design and compaction analysis - Environmentally sustainable materials and technologies - Advances in laboratory characterization of bituminous materials - Modeling of road materials and pavement performance prediction - Field measurement and in-situ characterization - Innovative materials for reinforcement and interlayer systems - Cracking and damage characterization of asphalt pavements - Rec...

  9. System for supporting conception in the field of surface treatments

    International Nuclear Information System (INIS)

    Evrard, J.M.; Gras, M.

    1989-01-01

    The application of the techniques issued from artificial intelligence for assisting the development of a computer technical memory on a representative subject, which is the surface treatments and coating in tribology, is illustrated. The development of the system is composed of several steps: data acquisition and formatting representation, data validation and software. Particular attention is given to the dialogue between the user and the system. The study shows that the development of the following points are indispensable: the possibility of following the user's reasoning and coming back to previous steps or exploring several parallel ways [fr

  10. Evaluation of Surface Treatment Methods on the Bond Strength of Zirconia Ceramics Systems, Resin Cements and Tooth Surface

    Directory of Open Access Journals (Sweden)

    Akkuş Emek

    2015-07-01

    Full Text Available Objectives: To compare the effects of airborne-particle abrasion (APA and tribochemical silica coating (TSC surface treatment methods on the shear bond strength of zirconia ceramics systems, resin cements and tooth surface

  11. Environmental performance assessment of a company of aluminum surface treatment

    Directory of Open Access Journals (Sweden)

    Susan Catieri Ramalho

    2013-08-01

    Full Text Available The purpose of this article was to evaluate the environmental performance of a medium-sized company that provides services for surface treatment of aluminum. The treatment is known as anodizing. The research method was qualitative numerical modeling. The environmental performance of the company was organized into five constructs: atmosphere, wastewater, energy and natural resources, solid waste, and legislation and management. Nineteen indicators were chosen to explain the five constructs. Ten employees of the company prioritized the constructs and evaluated the situation of the indicators by means of a scale of assessment. By means of a mathematical model, the general performance of the environmental operation was calculated at 74.5% of the maximum possible. The indicators that most contributed to the performance not to reach 100% were consumption of electricity and water consumption. The construct of worse performance was natural and energy resources. These are the priorities for future environmental improvement actions that the company may promote.

  12. Aerobic Biofilms Grown from Athabasca Watershed Sediments Are Inhibited by Increasing Concentrations of Bituminous Compounds

    Science.gov (United States)

    Lawrence, John R.; Sanschagrin, Sylvie; Roy, Julie L.; Swerhone, George D. W.; Korber, Darren R.; Greer, Charles W.

    2013-01-01

    Sediments from the Athabasca River and its tributaries naturally contain bitumen at various concentrations, but the impacts of this variation on the ecology of the river are unknown. Here, we used controlled rotating biofilm reactors in which we recirculated diluted sediments containing various concentrations of bituminous compounds taken from the Athabasca River and three tributaries. Biofilms exposed to sediments having low and high concentrations of bituminous compounds were compared. The latter were 29% thinner, had a different extracellular polysaccharide composition, 67% less bacterial biomass per μm2, 68% less cyanobacterial biomass per μm2, 64% less algal biomass per μm2, 13% fewer protozoa per cm2, were 21% less productive, and had a 33% reduced content in chlorophyll a per mm2 and a 20% reduction in the expression of photosynthetic genes, but they had a 23% increase in the expression of aromatic hydrocarbon degradation genes. Within the Bacteria, differences in community composition were also observed, with relatively more Alphaproteobacteria and Betaproteobacteria and less Cyanobacteria, Bacteroidetes, and Firmicutes in biofilms exposed to high concentrations of bituminous compounds. Altogether, our results suggest that biofilms that develop in the presence of higher concentrations of bituminous compounds are less productive and have lower biomass, linked to a decrease in the activities and abundance of photosynthetic organisms likely due to inhibitory effects. However, within this general inhibition, some specific microbial taxa and functional genes are stimulated because they are less sensitive to the inhibitory effects of bituminous compounds or can degrade and utilize some bitumen-associated compounds. PMID:24056457

  13. Treatment of severe ocular surface disorders with albumin eye drops.

    Science.gov (United States)

    Schargus, Marc; Kohlhaas, Markus; Unterlauft, Jan Darius

    2015-06-01

    Promising healing effects by albumin eye drops (AED) on the corneal epithelium have been demonstrated. The aim of this study was to analyze retrospectively if AED are an effective treatment for severe ocular surface defects and if recurrences can be reduced. Seventeen patients with persistent epithelial defects (PED) and 30 patients with sterile corneal ulcers (CU) were treated either with 5% AED or 0.1% hyaluronan eye drops (HED) 8 times daily until complete epithelium closure. Sizes of the corneal defects, length of treatment and follow-up period, as well as recurrence rate were evaluated. Follow-up of PED was carried out for 126 ± 21 days in the AED group and 142 ± 39 days in the HED group. For CU cases, regular follow-up visits were performed for 117 ± 15 days in the AED group and 112 ± 28 days in the HED group. Nine patients in PED group were treated for 11 ± 4 days with AED and the HED group (8 patients) was treated for 10 ± 3 days until corneal epithelium was closed, with only one recurrence in the HED group (P = 0.67). Fifteen patients in CU group were treated for 18 ± 6 days with AED and the HED group (15 patients) was treated for 21 ± 7 days until epithelial closure, with 1 recurrence in the AED group and 8 in the HED group (P = 0.03). This comparative retrospective case-control study showed that AED are able to close corneal epithelial defects like CU and PED as good as HED. Even though times of healing were similar for both treatments, AED seem to reduce the recurrence of sterile CU. Our findings suggest that AED might be beneficial in the management of ocular surface epithelial damage; however, further larger studies are necessary to confirm these results.

  14. Effects of Different Surface Treatments on Composite Repairs.

    Science.gov (United States)

    Batista, Graziela Ribeiro; Kamozaki, Maria Beatriz Beber; Gutierrez, Natália Cortez; Caneppele, Taciana Marco Ferraz; Rocha Gomes Torres, Carlos

    2015-08-01

    To evaluate the influence of different surface treatments on roughness and bond strength of composite repairs. 120 truncated conical specimens were prepared with composite Grandio SO (VOCO) and submitted to 5000 thermal cycles. Specimens were divided into 12 groups (n = 10) regarding the surface treatments: negative control (NC), without treatment; medium-grit diamond bur (MGD); coarse-grit diamond bur (CGD); conventional carbide bur (ConC); crosscut carbide bur (CutC); chemical vapor deposition diamond bur (CVD); sandblasting with aluminum oxide (AlO); Er:YAG laser 200 mJ/10 Hz (Er200); Er:YAG laser 60 mJ/10 Hz (Er50); Nd:YAG laser 120 mJ/15 Hz (Nd120); Nd:YAG laser 60 mJ/ 15Hz (Nd60); air abrasion with 110-μm silica modified aluminum oxide (Rocatec Plus-3M) (SIL). After the surface treatments, the surface roughness (Ra) was measured using a profilometer, and then the adhesive system Admira Bond (VOCO) was applied. Another truncated conical restoration was built up with the same composite over the bonded area of each specimen. In order to evaluate the cohesive strength, double-cone specimens were made and considered as a control group (CoheC). The specimens were submitted to tensile bond strength testing and the obtained data (MPa) were evaluated by one-way ANOVA, Tukey's and correlation tests. ANOVA showed significant differences among experimental groups for roughness and adhesive strength (p < 0.00). The roughness values (Ra) were: NC (0.21 ± 0.19)(c); ConC (0.30 ± 0.08)(c); CutC (0.50 ± 0.22)(cd); CVD (0.74 ± 0.14)(bd); MGD (0.89 ± 0.39)(ab); Er50 (0.89 ± 0.14)(ab); AlO (0.90 ± 0.07)(ab); Nd60 (0.94 ± 0.33ab; SIL (0.98 ± 0.07)(ab); Nd120 (1.10 ± 0.19)(a); CGD (1.10 ± 0.32)(a); Er200 (1.12 ± 0.21)(a). The results of the tensile bond strength test in MPa were: CGD (11.58 ± 3.03)(a); MGD (12.66 ± 3.82)(ab); NC (13.51 ± 3.95(ab); Nd120 (14.11 ± 5.95)(ab); ConC (14.73 ± 6.12)(ab); Er200 (15.51 ± 1.45)(abc); CVD (15.61 ± 5.00(abc); Er50 (16.44

  15. Roughness, surface energy, and superficial damages of CAD/CAM materials after surface treatment.

    Science.gov (United States)

    Strasser, Thomas; Preis, Verena; Behr, Michael; Rosentritt, Martin

    2018-02-05

    The aim of this study was to examine the effects of surface pre-treatment on CAD/CAM materials including ceramics, zirconia, resin-infiltrated ceramic, and resin-based composite. Specimens were made of ten CAD/CAM materials (Celtra Duo, Degudent, D; Vita Suprinity, Vita, D; E.max CAD, Ivoclar-Vivadent, FL; E.max ZirCAD, Ivoclar-Vivadent, FL; Vita Enamic, Vita, D; Cerasmart, GC, B; LAVA Ultimate, 3M, D; SHOFU Block HC, SHOFU, US; Grandio Blocs, VOCO, D; BRILLIANT Crios, Coltene, CH) and pretreated to represent clinical procedures (Hf 20 s/5%; phosphoric acid 20 s/37%; Monobond etch and prime (Ivoclar-Vivadent, FL); water-cooled diamond bur (80 μm; 4 μm); Al 2 O 3 -blasting (50 μm/1 bar, 50 μm/2 bar, 120 μm/1 bar, 120 μm/2 bar); untreated; manufacturer's instructions). SEM-analysis (Phenom, FEI, NL) of the surfaces was performed (magnifications ≤ 10,000×). Roughness values R a , R z (KJ 3D, Keyence, J), and surface energy SE (OCA15 plus, SCA20, DataPhysics, D) were determined (statistics: non-parametric Mann-Whitney U test/Kruskal-Wallis test for independent specimen, α = 0.05). Kruskal-Wallis revealed significant (p CAD/CAM materials require individual pre-treatment for optimized and protective surface activation. Cementation is a key factor for clinical success. Given the variety of available CAD/CAM materials, specific procedures are needed.

  16. Evaluation of chemical surface treatment methods for mitigation of PWSCC

    International Nuclear Information System (INIS)

    Dame, C.; Marks, C.; Olender, A.; Farias, J.

    2015-01-01

    As part of its mission to propose innovative and safe technologies to mitigate Primary Water Stress Corrosion Cracking (PWSCC) in Pressurized Water Reactors (PWR), EPRI recently initiated a program to evaluate potential new chemical surface treatments that might delay the occurrence of PWSCC such that no failure of components would be observed during their lifetime. Among the initial screening of more than thirty technologies, seven were selected for a more detailed review. The selected technologies were: nickel and nickel alloy plating, organic inhibitors, chromium-based inhibitors, silicon carbide, titanium-based inhibitors, rare earth metal (REM)-based inhibitors and encapsulation. The conclusions of the review of these technologies were that two of them were worth pursuing, titanium-based and REM-based inhibitors, and that evaluating the radiological consequences of injecting these products in the primary system, as well as assessing their efficacy to mitigate PWSCC, should be prioritized as the next required steps in qualification for implementation. (authors)

  17. Formation of periodic structures by surface treatments of polyamide fiber

    International Nuclear Information System (INIS)

    Yip, Joanne; Chan, Kwong; Sin, Kwan Moon; Lau, Kai Shui

    2006-01-01

    The processes of UV excimer laser irradiation (both high- and low-fluence) of polyamide fiber were systemically studied, including the surface temperature of the material during the treatment and possible mechanisms for the structure formation. The fluence applied in the high-fluence laser irradiation was above the ablation threshold of the material. The ablation of polymer can be described on the basis of photo-thermal bond breaking within the bulk material. The fluence applied in the low-fluence laser irradiation was far below the ablation threshold of the material. The development of low-fluence laser-induced structures is closely related to the absorption coefficient of the material, the laser fluence used, the polarization of the laser beam, the angle of incidence, and the number of laser pulses applied

  18. Influence of hydrophobic surface treatment toward performance of air filter

    Science.gov (United States)

    Shahfiq Zulkifli, Nazrul; Zaini Yunos, Muhamad; Ahmad, Azlinnorazia; Harun, Zawati; Akhair, Siti Hajar Mohd; Adibah Raja Ahmad, Raja; Hafeez Azhar, Faiz; Rashid, Abdul Qaiyyum Abd; Ismail, Al Emran

    2017-08-01

    This study investigated the performance of hydrophobic surface treatment by using silica aerogel powder via spray coating techniques. Hydrophobic properties were determined by measuring the level of the contact angle. Meanwhile, performance was evaluated in term of the hydrogen gas flow and humidity rejection. The results are shown by contact angle that the microstructure filter, especially in the upper layer and sub-layer has been changed. The results also show an increase of hydrophobicity due to the increased quantity of silica aerogel powder. Results also showed that the absorption and rejection filter performance filter has increased after the addition of silica aerogel powder. The results showed that with the addition of 5 grams of powder of silica aerogel have the highest result of wetting angle 134.11°. The highest humidity rejection found with 5 grams of powder of silica aerogel.

  19. Atmospheric pressure dielectric barrier discharges for sterilization and surface treatment

    Energy Technology Data Exchange (ETDEWEB)

    Chin, O. H.; Lai, C. K.; Choo, C. Y.; Wong, C. S.; Nor, R. M. [Plasma Technology Research Centre, Physics Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Thong, K. L. [Microbiology Division, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-04-24

    Atmospheric pressure non-thermal dielectric barrier discharges can be generated in different configurations for different applications. For sterilization, a parallel-plate electrode configuration with glass dielectric that discharges in air was used. Gram-negative bacteria (Escherichia coli and Salmonella enteritidis) and Gram-positive bacteria (Bacillus cereus) were successfully inactivated using sinusoidal high voltage of ∼15 kVp-p at 8.5 kHz. In the surface treatment, a hemisphere and disc electrode arrangement that allowed a plasma jet to be extruded under controlled nitrogen gas flow (at 9.2 kHz, 20 kVp-p) was applied to enhance the wettability of PET (Mylar) film.

  20. The treatment of surface oxide for reactor repair welding

    International Nuclear Information System (INIS)

    Morgan-Warren, E.J.

    1988-01-01

    A description is presented of potential methods for the treatment of surface oxide in magnox reactors in preparation for repair welding. Advanced weld process fluxing techniques together with mechanical, thermal and chemical cleaning methods are examined in relation to their state of development and feasibility. It is considered that in the short term, mechanical cleaning methods are most likely to be applicable. Weld process fluxing is shown to be a viable technique where the oxide thickness is low, and could form the basis of a medium term development. Possible longer term developments include chemical and thermal cleaning techniques. Recommendations are made for a number of work areas with a view to developing a strategy applicable to the magnox repair programme. (author)

  1. Infiltration of surface mined land reclaimed by deep tillage treatments

    International Nuclear Information System (INIS)

    Chong, S.K.; Cowsert, P.

    1994-01-01

    Surface mining of coal leads to the drastic disturbance of soils. Compaction of replaced subsoil and topsoil resulting from hauling, grading, and leveling procedures produces a poor rooting medium for crop growth. Soil compaction results in high bulk density, low macroporosity, poor water infiltration capacity, and reduced elongation of plant roots. In the United States, Public Law 95-87 mandates that the rooting medium of mined soils have specific textural characteristics and be graded and shaped to a topography similar to premining conditions. Also, crop productivity levels equivalent to those prior to mining must be achieved, especially for prime farmland. Alleviation of compaction has been the major focus of reclamation, and recently new techniques to augment the rooting zone with deep-ripping and loosening equipment have come to the forefront. Several surface mine operators in the Illinois coal basin are using deep tillage equipment that is capable of loosening soils to greater depths than is possible with conventional farm tillage equipment. Information on the beneficial effects of these loosening procedures on soil hydrological properties, such as infiltration, runoff potential, erosion, and water retention, is extremely important for future mined land management. However, such information is lacking. In view of the current yield demonstration regulation for prime farmland and other unmined soils, it is important that as much information as possible be obtained concerning the effect of deep tillage on soil hydrologic properties. The objectives of this study are: (1) to compare infiltration rates and related soil physical properties of mined soils reclaimed by various deep tillage treatments and (2) to study the temporal variability of infiltration and related physical properties of the reclaimed mined soil after deep tillage treatment

  2. Use of additives to improve the capacity of bituminous mixtures to be heated by means of microwaves

    International Nuclear Information System (INIS)

    Gallego, J.; Val, M.A. del; Contreras, V.; Páez, A.

    2017-01-01

    This study examines the potential of adding electric arc furnace slag to bituminous mixtures to be heated by microwaves. The susceptibility of bituminous mixtures to microwave energy is limited and so, in order to improve the energy performance of the heating process, it is necessary to incorporate additives or components to the mixture so as to improve the capacity for microwave heating. The article presents the results of adding various components, (steel wool, scrap tire wire, silicon carbide, iron filings) and an alternative aggregate: electric arc furnace slag. According to the results obtained in the laboratory, slag addition of at least 5% by weight of the bituminous mixture represents the best option for both technical and economic reasons. The results may promote the valorization of this steel industry residue in bituminous mixtures by improving microwave heating response. [es

  3. Chitosan Immobilized on Silica Surface for Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    Tetyana BUDNYAK

    2014-06-01

    Full Text Available Adsorbents of natural origin are widely used for industrial wastewater treatment in order to replace current costly methods of heavy metals removing from solutions. For that purpose, immobilization of chitosan on the silica gel surface by crosslinking of adsorbed biopolymer with glutaraldehyde was carried out. Anchorage of chitosan on the silica surface was confirmed by IR spectroscopy. Concentration of immobilized chitosan was estimated using thermogravimetric analysis. The adsorption of microquantities of Zn(II, Cu(II, Cd(II, Pb(II, Fe(III, V(V and Mo(VI ions from aqueous solutions by obtained composite has been studied. The highest sorption capacities were observed with respect to zinc (0.46 mmol/g, molybdenum- and vanadium-containing ions (0.31 mmol/g. Diffuse reflectance electronic spectra of samples with different content of adsorbed metal and kinetic adsorption characteristics of the composite adsorbent were estimated. DOI: http://dx.doi.org/10.5755/j01.ms.20.2.4975

  4. Surface treatment on polyethylenimine interlayer to improve inverted OLED performance

    Science.gov (United States)

    Wei, Chang-Ting; Zhuang, Jin-Yong; Chen, Ya-Li; Zhang, Dong-Yu; Su, Wen-Ming; Cui, Zheng

    2016-10-01

    Polyethylenimine (PEI) interlayer rinsing with different solvents for inverted organic light emitting diodes (OLEDs) is systematically studied in this paper. In comparison with the pristine one, the maximum current efficiency (CE max) and power efficiency (PE max) are enhanced by 21% and 22% for the device rinsing by ethylene glycol monomethyl ether (EEA). Little effect is found on the work function of the PEI interlayer rinsed by deionized water (DI), ethanol (EtOH), and EEA. On the other hand, the surface morphologies of PEI through different solvent treatments are quite different. Our results indicates that the surface morphology is the key to improving the device performance for IOLED as the work function of PEI keeps stable. Project supported by the National Key Basic Research Project of China (Grant No. 2015CB351901), the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA09020201), the Youth Innovation Promotion Association of Chinese Academy of Sciences (Grant No. 2013206), the National Natural Science Foundation of China (Grant No. 21402233), and the Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK2012631 and BK20140387).

  5. Studies on the treatment of surface water using rajma seeds

    Science.gov (United States)

    Merlin, S. Babitha; Abirami, M.; Kumar, R. Suresh

    2018-03-01

    Indiscriminate disposal of wastewater with suspended solids have led to higher amount of pollution to the natural water bodies. Turbidity removal becomes an essential part in the water treatment when surface water is used for drinking purpose, this can be achieved by means of coagulation process. Coagulation process is the dosing of a coagulant in water, resulting in the destabilization of negatively charged particles. Commercial coagulants which were widely used can synthesize by-products in turn may pollute the environment and deteriorate the ecosystem at a slow rate. So, now-a-days natural coagulants are used as a potential substitute because it's biodegradable, ecofriendly and non-toxic. In this study, the turbid surface water samples were treated using powdered seeds of Rajma (natural coagulant) followed by variations in dosage, settling time and pH were also studied. From the results obtained, it was found that the Rajma seeds powder achieved 48.80% efficiency for 0.5 g/l of optimum dose at pH 6 for 20 min settling time respectively.

  6. Topographical evaluation of different glass and quartz fiber post surface treatments by a tridimensional surface roughness test.

    Science.gov (United States)

    Soares, Leandro Passos; Dias, Katia Regina Hostilio Cervantes; de Vasconcellos, Adalberto Bastos; Sampaio, Eduardo Martins; Limaverde, Aricelso Maia; Barceleiro, Marcos de Oliveira

    2010-01-01

    A tridimensional surface roughness test evaluation is a nondestructive method that can be used to perform a topographic analysis of different surface treatments for glass and quartz fiber posts. This study divided 75 fiber posts into three groups according to their manufacturer. Each group was divided into five subgroups (n = 5), according to the surface treatment each received: immersion in hydrofluoric acid, sandblasting, immersion in hydrogen peroxide, sandblasting followed by immersion in hydrofluoric acid, or sandblasting followed by immersion in hydrogen peroxide. Surface roughness was measured using a tridimensional surface roughness test and analyzed with three-dimensional analysis software. Results were statistically analyzed using Student's t-test. The only surface treatment to modify the surface topography of glass and quartz fiber posts and provide a significant increase in roughness was sandblasting airborne-particle abrasion with 50 micro alumina at a distance of 30 mm, using 2.5 bars of pressure for five seconds.

  7. Water Accumulation and Behavior of Surfactant Associated with Moisture Permeation in Bituminous Pavement on Concrete Deck Bridge

    OpenAIRE

    Sasaki, Iwao; Moriyoshi, Akihiro; Tsunekawa, Masami

    2006-01-01

    Water-related damage is one of the major problems for the durability of the bituminous pavement and concrete slabs of concrete deck bridges. In particular, damage can be drastically accelerated by the intervention of water and some chemicals such as surfactants and salts. Therefore, the mass transfer mechanism of water and the mechanism of chemical absorption in pavement materials are important to study. The authors previously pointed out that water storage in bituminous pavement layers is ca...

  8. Response surface optimization of electrochemical treatment of textile dye wastewater

    International Nuclear Information System (INIS)

    Koerbahti, Bahadir K.

    2007-01-01

    The electrochemical treatment of textile dye wastewater containing Levafix Blue CA, Levafix Red CA and Levafix Yellow CA reactive dyes was studied on iron electrodes in the presence of NaCl electrolyte in a batch electrochemical reactor. The wastewater was synthetically prepared in relatively high dye concentrations between 400 mg/L and 2000 mg/L. The electrochemical treatment of textile dye wastewater was optimized using response surface methodology (RSM), where current density and electrolyte concentration were to be minimized while dye removal and turbidity removal were maximized at 28 deg. C reaction temperature. Optimized conditions under specified cost driven constraints were obtained for the highest desirability at 6.7 mA/cm 2 , 5.9 mA/cm 2 and 5.4 mA/cm 2 current density and 3.1 g/L, 2.5 g/L and 2.8 g/L NaCl concentration for Levafix Blue CA, Levafix Red CA and Levafix Yellow CA reactive textile dyes, respectively

  9. Assessment of underground coal gasification in bituminous coals: potential UCG products and markets. Final report, Phase I

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-01-31

    The following conclusions were drawn from the study: (1) The US will continue to require new sources of energy fuels and substitutes for petrochemical feedstocks into the foreseeable future. Most of this requirement will be met using coal. However, the cost of mining, transporting, cleaning, and preparing coal, disposing of ash or slag and scrubbing stack gases continues to rise; particularly, in the Eastern US where the need is greatest. UCG avoids these pitfalls and, as such, should be considered a viable alternative to the mining of deeper coals. (2) Of the two possible product gases LBG and MBG, MBG is the most versatile. (3) The most logical use for UCG product in the Eastern US is to generate power on-site using a combined-cycle or co-generation system. Either low or medium Btu gas (LBG or MBG) can be used. (4) UCG should be an option whenever surface gasification is considered; particularly, in areas where deeper, higher sulfur coal is located. (5) There are environmental and social benefits to use of UCG over surface gasification in the Eastern US. (6) A site could be chosen almost anywhere in the Illinois and Ohio area where amenable UCG coal has been determined due to the existence of existing transportation or transmission systems. (7) The technology needs to be demonstrated and the potential economic viability determined at a site in the East-North-Central US which has commercial quantities of amenable bituminous coal before utilities will show significant interest.

  10. Radwaste treatment and disposal

    International Nuclear Information System (INIS)

    Ehn, L.; Breza, M.; Pekar, A.

    2000-01-01

    In this lecture is given the basic information, that is concerning on the RAW treatment and long term disposal of the treated RAW in repository at Mochovce. Then here is given the basic technical and technological information, that is concerning bituminization, plant, the vitrification unit, center for the RAW-treatment (BSC) and repository at Mochovce. (authors)

  11. Surface treatment of silicate based glass: base Piranha treatment versus 193nm laser processing

    Science.gov (United States)

    Canning, J.; Petermann, I.; Cook, K.

    2012-02-01

    Contact angle measurements of water on pathology grade borosilicate glass microscope slides before and after base piranha treatment are compared to treatment with 193nm laser irradiation. 193nm irradiation in the presence of hydrogen was also explored. Within experimental resolution, the observed changes in contact angle as a result of treatment either with base Piranha solution or with laser processing are identical. The contact angle, a, in both cases is reduced from a = (27 +/- 6)º to a = (8 +/- 3)º with treatment. However, for the piranha base method, there is an observed reversal over time either fully recovering or partially recovering within hours. By contrast, with laser processed, the increased surface wettability is retained with no change for more than 15 hours. In all cases, surface functionalisation, as measured by contact angle, with (3-mercaptopropyl)trimethoxysilane (MPTS) is found to be largely independent of any processing. We conclude that the method of contact angle as a means for qualitatively asserting improvements in attachment is unjustified.

  12. Long-term behaviour of bituminized waste: modelling self-irradiation and leaching

    Energy Technology Data Exchange (ETDEWEB)

    Simondi-Teisseire, B.; Vistoli, P.P.; Libert, M.; Gilardi, T. [CEA Cadarache, Dept. de Physico-Chimie, DPC, 13 - Saint-Paul-lez-Durance (France); Chaix, P. [CEA Saclay, Dept. de Physico-Chimie, DPC, 91 - Gif-sur-Yvette (France); Blanc, V. [Cogema, 78 - Saint Quentin en Yvelines (France)

    2001-07-01

    During interim storage, the main evolution factor of bituminized wastes is radiolysis, due to self-irradiation. In deep disposal conditions, after site re-saturation and corrosion of the containers, the main evolution will be due to leaching. This paper deals with two models designed to describe respectively radiolytic gas evacuation (JACOB- 2) and bituminized waste leaching (COLONBO), and some of the typical results obtained from these two models. The first model describes radiolytic gas production, diffusive transport of gas, bubble nucleation and ripening and movement under buoyancy. The second one is based on descriptions of water sorption, solubilization, and diffusion into the matrix, water uptake by the most soluble salts leading to alteration of the matrix and finally to diffusive transport of the salts outside the bitumenisate. (author)

  13. Research on the thermal decomposition of Mongolian Baganuur lignite and Naryn sukhait bituminous coal

    Directory of Open Access Journals (Sweden)

    A. Ariunaa

    2016-03-01

    Full Text Available The technical characteristics, elemental composition of the organic and mineral matters, ash melting behaviors and carbonization and gasification reactivities of coals from Baganuur and Naryn sukhait deposits were investigated. The results of proximate and ultimate analysis confirmed that the coal from Baganuur deposit can be graded as a low rank lignite B2 mark coal and Naryn sukhait coal is a bituminous G mark one. The carbonization and gasification experiments were performed using TGA apparatus and fixed bed quartz reactor. The data obtained with two experimental reactors showed that Baganuur lignite had lower thermal stability and much higher CO2 gasification reactivity at 950°C as compared to those for Naryn sukhait bituminous coal.Mongolian Journal of Chemistry 16 (42, 2015, 22-29

  14. Improved adhesion of Ag NPs to the polyethylene terephthalate surface via atmospheric plasma treatment and surface functionalization

    Science.gov (United States)

    Shen, Tao; Liu, Yong; Zhu, Yan; Yang, De-Quan; Sacher, Edward

    2017-07-01

    Ag nanoparticles (NPs) have been widely applied, as important antibacterial materials, on textile and polymer surfaces. However, their adhesion to nonreactive polymer surfaces is generally too weak for many applications. Here, we propose a two-step process, atmospheric plasma treatment followed by a surface chemical modification process, which enhances their adhesion to polyethylene terephthalate (PET) surfaces. We found that, compared to either plasma treatments or surface chemical functionalizations, alone, this combination greatly enhanced their adhesion. The plasma treatment resulted in an increase of active sites (sbnd OH, sbnd CHdbnd O and COOH) at the PET surface, permitting increased bonding to 3-aminopropyltriethoxysilane (APTES), whose sbnd NH2 groups were then able to form a bonding complex with the Ag NPs.

  15. Estimated Valuation of the Cost of Road Construction with the Use of Composite Cationic Bituminous Structures

    OpenAIRE

    Vorotynseva Anna; Ovsiannikov Andrey; Bolgov Vladimir

    2017-01-01

    The need for formation of prices for road construction works producing, by using composite of cationic bituminous structures, is dictated by absence of this type of work in estimate-normative base, due to the fact that this type of materials had never been used before. Estimated specifications could be used either for determination of work cost or for substantiation of efficiency of using new type of materials. This paper provides basic concepts, related to formation of estimate-normative bas...

  16. Study on Plastic Coated Overburnt Brick Aggregate as an Alternative Material for Bituminous Road Construction

    OpenAIRE

    Sarkar, Dipankar; Pal, Manish; Sarkar, Ashoke K.

    2016-01-01

    There are different places in India where natural stone aggregates are not available for constructional work. Plastic coated OBBA can solve the problem of shortage of stone aggregate to some extent. The engineers are always encouraged to use locally available materials. The present investigation is carried out to evaluate the plastic coated OBBA as an alternative material for bituminous road construction. Shredded waste plastics are mixed with OBBA in different percentages as 0.38, 0.42, 0.46...

  17. Surface treatment of glass substrates for the preparation of long-lived carbon stripper foils

    International Nuclear Information System (INIS)

    Takeuchi, Suehiro; Takekoshi, Eiko

    1981-02-01

    Glass substrates having uniformly distributed microscopic grains on the surfaces are useful to make long-lived carbon stripper foils for heavy ions. A method of surface treatment of glass substrates to form the surface structure is described. This method consists of precipitation of glass components, such as soda, onto the surfaces in a hot and humid atmosphere and a fogging treatment of forming microscopic grains of the precipitated substances. Some results of studies on the treatment conditions are also presented. (author)

  18. Carbon Isotope Analyses of Individual Hydrocarbon Molecules in Bituminous Coal, Oil Shale and Murchison Meteorite

    Directory of Open Access Journals (Sweden)

    Kyoungsook Kim

    1998-06-01

    Full Text Available To study the origin of organic matter in meteorite, terrestrial rocks which contain organic compounds similar to the ones found in carbonaceous chondrites are studied and compared with Murchison meteorite. Hydrocarbon molecules were extracted by benzene and methanol from bituminous coal and oil shale and the extracts were partitioned into aliphatic, aromatic, and polar fractions by silica gel column chromatography. Carbon isotopic ratios in each fractions were analysed by GC-C-IRMS. Molecular compound identifications were carried by GC-MS Engine. Bituminous coal and oil shale show the organic compound composition similar to that of meteorite. Oil shale has a wide range of δ(13C, -20.1%_0 - -54.4%_0 compared to bituminous coal, -25.2%_0 - -34.3%_0. Delta values of several molecular compounds in two terrestrial samples are different. They show several distinct distributions in isotopic ratios compared to those of meteorite; Murchison meteorite has a range of δ(13C from -13%_0 to +30%_0. These results provide interpretation for the source and the formation condition of each rock, in particular alteration and migration processes of organic matter. Especially, they show an important clue whether some hydrocarbon molecules observed in meteorite are indigenous or not.

  19. Prediction of Marshall Parameters of Modified Bituminous Mixtures Using Artificial Intelligence Techniques

    Directory of Open Access Journals (Sweden)

    Sunil Khuntia

    2014-09-01

    Full Text Available This study presents the application of artificial neural networks (ANN and least square support vector machine (LS-SVM for prediction of Marshall parameters obtained from Marshall tests for waste polyethylene (PE modified bituminous mixtures. Waste polyethylene in the form of fibres processed from utilized milk packets has been used to modify the bituminous mixes in order to improve their engineering properties. Marshall tests were carried out on mix specimens with variations in polyethylene and bitumen contents. It has been observed that the addition of waste polyethylene results in the improvement of Marshall characteristics such as stability, flow value and air voids, used to evaluate a bituminous mix. The proposed neural network (NN model uses the quantities of ingredients used for preparation of Marshall specimens such as polyethylene, bitumen and aggregate in order to predict the Marshall stability, flow value and air voids obtained from the tests. Out of two techniques used, the NN based model is found to be compact, reliable and predictable when compared with LS-SVM model. A sensitivity analysis has been performed to identify the importance of the parameters considered.

  20. Continuous bench-scale slurry catalyst testing direct coal liquefaction rawhide sub-bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, R.F.; Coless, L.A.; Davis, S.M. [and others

    1995-12-31

    In 1992, the Department of Energy (DOE) sponsored research to demonstrate a dispersed catalyst system using a combination of molybdenum and iron precursors for direct coal liquefaction. This dispersed catalyst system was successfully demonstrated using Black Thunder sub-bituminous coal at Wilsonville, Alabama by Southern Electric International, Inc. The DOE sponsored research continues at Exxon Research and Development Laboratories (ERDL). A six month continuous bench-scale program using ERDL`s Recycle Coal Liquefaction Unit (RCLU) is planned, three months in 1994 and three months in 1995. The initial conditions in RCLU reflect experience gained from the Wilsonville facility in their Test Run 263. Rawhide sub-bituminous coal which is similar to the Black Thunder coal tested at Wilsonville was used as the feed coal. A slate of five dispersed catalysts for direct coal liquefaction of Rawhide sub-bituminous coal has been tested. Throughout the experiments, the molybdenum addition rate was held constant at 100 wppm while the iron oxide addition rate was varied from 0.25 to 1.0 weight percent (dry coal basis). This report covers the 1994 operations and accomplishments.

  1. Study on Plastic Coated Overburnt Brick Aggregate as an Alternative Material for Bituminous Road Construction

    Directory of Open Access Journals (Sweden)

    Dipankar Sarkar

    2016-01-01

    Full Text Available There are different places in India where natural stone aggregates are not available for constructional work. Plastic coated OBBA can solve the problem of shortage of stone aggregate to some extent. The engineers are always encouraged to use locally available materials. The present investigation is carried out to evaluate the plastic coated OBBA as an alternative material for bituminous road construction. Shredded waste plastics are mixed with OBBA in different percentages as 0.38, 0.42, 0.46, 0.50, 0.54, and 0.60 of the weight of brick aggregates. Marshall Method of mix design is carried out to find the optimum bitumen content of such bituminous concrete mix prepared by plastic coated OBBA. Bulk density, Marshall Stability, flow, Marshall Quotient, ITS, TSR, stripping, fatigue life, and deformations have been determined accordingly. Marshall Stability value of 0.54 percent of plastic mix is comparatively higher than the other mixes except 0.60 percent of plastic mix. Test results are within the prescribed limit for 0.54 percent of plastic mix. There is a significant reduction in rutting characteristics of the same plastic mix. The fatigue life of the mix is also significantly higher. Thus plastic coated OBBA is found suitable in construction of bituminous concrete road.

  2. JV Task 126 - Mercury Control Technologies for Electric Utilities Burning Bituminous Coal

    Energy Technology Data Exchange (ETDEWEB)

    Jason Laumb; John Kay; Michael Jones; Brandon Pavlish; Nicholas Lentz; Donald McCollor; Kevin Galbreath

    2009-03-29

    The EERC developed an applied research consortium project to test cost-effective mercury (Hg) control technologies for utilities burning bituminous coals. The project goal was to test innovative Hg control technologies that have the potential to reduce Hg emissions from bituminous coal-fired power plants by {ge}90% at costs of one-half to three-quarters of current estimates for activated carbon injection (ACI). Hg control technology evaluations were performed using the EERC's combustion test facility (CTF). The CTF was fired on pulverized bituminous coals at 550,000 Btu/hr (580 MJ/hr). The CTF was configured with the following air pollution control devices (APCDs): selective catalytic reduction (SCR) unit, electrostatic precipitator (ESP), and wet flue gas desulfurization system (WFDS). The Hg control technologies investigated as part of this project included ACI (three Norit Americas, Inc., and eleven Envergex sorbents), elemental mercury (Hg{sup 0}) oxidation catalysts (i.e., the noble metals in Hitachi Zosen, Cormetech, and Hitachi SCR catalysts), sorbent enhancement additives (SEAs) (a proprietary EERC additive, trona, and limestone), and blending with a Powder River Basin (PRB) subbituminous coal. These Hg control technologies were evaluated separately, and many were also tested in combination.

  3. Analytical modelling for ultrasonic surface mechanical attrition treatment

    Directory of Open Access Journals (Sweden)

    Guan-Rong Huang

    2015-07-01

    Full Text Available The grain refinement, gradient structure, fatigue limit, hardness, and tensile strength of metallic materials can be effectively enhanced by ultrasonic surface mechanical attrition treatment (SMAT, however, never before has SMAT been treated with rigorous analytical modelling such as the connection among the input energy and power and resultant temperature of metallic materials subjected to SMAT. Therefore, a systematic SMAT model is actually needed. In this article, we have calculated the averaged speed, duration time of a cycle, kinetic energy and kinetic energy loss of flying balls in SMAT for structural metallic materials. The connection among the quantities such as the frequency and amplitude of attrition ultrasonic vibration motor, the diameter, mass and density of balls, the sample mass, and the height of chamber have been considered and modelled in details. And we have introduced the one-dimensional heat equation with heat source within uniform-distributed depth in estimating the temperature distribution and heat energy of sample. In this approach, there exists a condition for the frequency of flying balls reaching a steady speed. With these known quantities, we can estimate the strain rate, hardness, and grain size of sample.

  4. Bioactive carbon-PEEK composites prepared by chemical surface treatment.

    Science.gov (United States)

    Miyazaki, Toshiki; Matsunami, Chisato; Shirosaki, Yuki

    2017-01-01

    Polyetheretherketone (PEEK) has attracted much attention as an artificial intervertebral spacer for spinal reconstruction. Furthermore, PEEK plastic reinforced with carbon fiber has twice the bending strength of pure PEEK. However, the PEEK-based materials do not show ability for direct bone bonding, i.e., bioactivity. Although several trials have been conducted for enabling PEEK with bioactivity, few studies have reported on bioactive surface modification of carbon-PEEK composites. In the present study, we attempted the preparation of bioactive carbon-PEEK composites by chemical treatments with H 2 SO 4 and CaCl 2 . Bioactivity was evaluated by in vitro apatite formation in simulated body fluid (SBF). The apatite formation on the carbon-PEEK composite was compared with that of pure PEEK. Both pure PEEK and carbon-PEEK composite formed the apatite in SBF when they were treated with H 2 SO 4 and CaCl 2 ; the latter showed higher apatite-forming ability than the former. It is conjectured that many functional groups able to induce the apatite nucleation, such as sulfo and carboxyl groups, are incorporated into the dispersed carbon phase in the carbon-PEEK composites. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Improved adhesion of Ag NPs to the polyethylene terephthalate surface via atmospheric plasma treatment and surface functionalization

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Tao [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, 253 Xuefu Rd, Kunming, Yunnan, 650093 (China); Liu, Yong [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, 253 Xuefu Rd, Kunming, Yunnan, 650093 (China); Solmont Technology Wuxi Co., Ltd. 228 Linghu Blvd. Tianan Tech Park, A1-602, Xinwu District, Wuxi, Jiangsu 214135 (China); Zhu, Yan, E-mail: zhuyan@kmust.edu.cn [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, 253 Xuefu Rd, Kunming, Yunnan, 650093 (China); Yang, De-Quan, E-mail: dequan.yang@gmail.com [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, 253 Xuefu Rd, Kunming, Yunnan, 650093 (China); Solmont Technology Wuxi Co., Ltd. 228 Linghu Blvd. Tianan Tech Park, A1-602, Xinwu District, Wuxi, Jiangsu 214135 (China); Sacher, Edward [Regroupement Québécois de Matériaux de Pointe, Department of Engineering Physics, École Polytechnique de Montréal, Case Postale 6079, succursale Centre-Ville, Montréal, Québec H3C 3A7 (Canada)

    2017-07-31

    Highlights: • A two-step process has been developed to enhance the adhesion of immobilized Ag NPs to the PET surface. • The method is simple, easy to use and low-cost for mass production. • The increased density of active sites (−OH, −CH=O and COOH) at the PET surface, after plasma treatment, permits increased reaction with 3-aminopropyltriethoxysilane (APTES). • The presence of APTES with high surface density permits −NH{sub 2}-Ag complex formation, increasing the adhesion of the Ag NPs. - Abstract: Ag nanoparticles (NPs) have been widely applied, as important antibacterial materials, on textile and polymer surfaces. However, their adhesion to nonreactive polymer surfaces is generally too weak for many applications. Here, we propose a two-step process, atmospheric plasma treatment followed by a surface chemical modification process, which enhances their adhesion to polyethylene terephthalate (PET) surfaces. We found that, compared to either plasma treatments or surface chemical functionalizations, alone, this combination greatly enhanced their adhesion. The plasma treatment resulted in an increase of active sites (−OH, −CH=O and COOH) at the PET surface, permitting increased bonding to 3-aminopropyltriethoxysilane (APTES), whose −NH{sub 2} groups were then able to form a bonding complex with the Ag NPs.

  6. Status of surface treatment in endosseous implant: A literary overview

    Directory of Open Access Journals (Sweden)

    Gupta Ankur

    2010-01-01

    Full Text Available The attachment of cells to titanium surfaces is an important phenomenon in the area of clinical implant dentistry. A major consideration in designing implants has been to produce surfaces that promote desirable responses in the cells and tissues. To achieve these requirements, the titanium implant surface can be modified in various ways. This review mainly focuses on the surface topography of dental implants currently in use, emphasizing the association of reported variables with biological outcome.

  7. Chemical treatment of zinc surface and its corrosion inhibition studies

    Indian Academy of Sciences (India)

    WINTEC

    elements are capable of forming thin film or molecular layers on the metal surface (Abdel Aal et al 1983; Lakhan. Jha et al 1991; Maja et al 1993; Rajappa and .... solution at 298 K. The surface contained small cavities, which are distributed over the entire surface and a needle- like deposit (corrosion product) was observed.

  8. Improvement of silicon direct bonding using surfaces activated by hydrogen plasma treatment

    CERN Document Server

    Choi, W B; Lee Jae Sik; Sung, M Y

    2000-01-01

    The plasma surface treatment, using hydrogen gas, of silicon wafers was studied as a pretreatment for silicon direct bonding. Chemical reactions of the hydrogen plasma with the surfaces were used for both surface activation and removal of surface contaminants. Exposure of the silicon wafers to the plasma formed an active oxide layer on the surface. This layer was hydrophilic. The surface roughness and morphology were examined as functions of the plasma exposure time and power. The surface became smoother with shorter plasma exposure time and lower power. In addition, the plasma surface treatment was very efficient in removing the carbon contaminants on the silicon surface. The value of the initial surface energy, as estimated by using the crack propagation method, was 506 mJ/M sup 2 , which was up to about three times higher than the value for the conventional direct bonding method using wet chemical treatments.

  9. Sphagnum mosses from 21 ombrotrophic bogs in the athabasca bituminous sands region show no significant atmospheric contamination of "heavy metals".

    Science.gov (United States)

    Shotyk, William; Belland, Rene; Duke, John; Kempter, Heike; Krachler, Michael; Noernberg, Tommy; Pelletier, Rick; Vile, Melanie A; Wieder, Kelman; Zaccone, Claudio; Zhang, Shuangquan

    2014-11-04

    Sphagnum moss was collected from 21 ombrotrophic (rain-fed) peat bogs surrounding open pit mines and upgrading facilities of Athabasca bituminous sands in Alberta (AB). In comparison to contemporary Sphagnum moss from four bogs in rural locations of southern Germany (DE), the AB mosses yielded lower concentrations of Ag, Cd, Ni, Pb, Sb, and Tl, similar concentrations of Mo, but greater concentrations of Ba, Th, and V. Except for V, in comparison to the "cleanest", ancient peat samples ever tested from the northern hemisphere (ca. 6000-9000 years old), the concentrations of each of these metals in the AB mosses are within a factor of 3 of "natural, background" values. The concentrations of "heavy metals" in the mosses, however, are proportional to the concentration of Th (a conservative, lithophile element) and, therefore, contributed to the plants primarily in the form of mineral dust particles. Vanadium, the single most abundant trace metal in bitumen, is the only anomaly: in the AB mosses, V exceeds that of ancient peat by a factor of 6; it is therefore enriched in the mosses, relative to Th, by a factor of 2. In comparison to the surface layer of peat cores collected in recent years from across Canada, from British Columbia to New Brunswick, the Pb concentrations in the mosses from AB are far lower.

  10. Fretting of AISI 9310 and selected fretting resistant surface treatments

    Science.gov (United States)

    Bill, R. C.

    1977-01-01

    Fretting wear experiments were conducted with uncoated AISI 9310 mating surfaces, and with combinations incorporating a selected coating to one of the mating surfaces. Wear measurements and SEM observations indicated that surface fatigue, as made evident by spallation and surface crack formation, is an important mechanism in promoting fretting wear to uncoated 9310. Increasing humidity resulted in accelerated fretting, and a very noticeable difference in nature of the fretting debris. Of the coatings evaluated, alumimum bronze with a polyester additive was most effective at reducing wear and minimizing fretting damage to the mating uncoated surface, by means of a self-lubricating film that developed on the fretting surfaces. Chromium plate performed as an effective protective coating, itself resisting fretting and not accelerating damage to the uncoated surface.

  11. Effects of surface inactivation, high temperature drying and preservative treatment on surface roughness and colour of alder and beech wood

    Science.gov (United States)

    Aydin, Ismail; Colakoglu, Gursel

    2005-10-01

    Although extensive research has been conducted in wood surface quality analysis, a unified approach to surface quality characterisation does not exist. Measurements of the variation in surface roughness and surface colour are used widely for the evaluation of wood surface quality. Colour is a basic visual feature for wood and wood-based products. Colour measurement is one of the quality control tests that should be carried out because the colour deviations are spotted easily by the consumers. On the other hand, a common problem faced by plywood manufacturers is panel delamination, for which a major cause is poor quality glue-bonds resulting from rough veneer. Rotary cut veneers with dimensions of 500 mm × 500 mm × 2 mm manufactured from alder ( Alnus glutinosa subsp. barbata) and beech ( Fagus orientalis Lipsky) logs were used as materials in this study. Veneer sheets were oven-dried in a veneer dryer at 110 °C (normal drying temperature) and 180 °C (high drying temperature) after peeling process. The surfaces of some veneers were then exposed at indoor laboratory conditions to obtain inactive wood surfaces for glue bonds, and some veneers were treated with borax, boric acid and ammonium acetate solutions. After these treatments, surface roughness and colour measurements were made on veneer surfaces. High temperature drying process caused a darkening on the surfaces of alder and beech veneers. Total colour change value (Δ E*) increased linear with increasing exposure time. Among the treatment solutions, ammonium acetate caused the biggest colour change while treatment with borax caused the lowest changes in Δ E* values. Considerable changes in surface roughness after preservative treatment did not occur on veneer surfaces. Generally, no clear changes were obtained or the values mean roughness profile ( Ra) decreased slightly in Ra values after the natural inactivation process.

  12. Gliding arc surface treatment of glass fibre reinforced polyester enhanced by ultrasonic irradiation

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Singh, Shailendra Vikram; Bardenshtein, Alexander

    2010-01-01

    that polar functional groups were introduced at the surface by the gliding arc treatment, and that the treatment efficiency was enhanced by the ultrasonic irradiation, indicating that the adhesive property would be improved. The results are extensively discussed in terms of the plasma conditions......During atmospheric pressure plasma surface treatment, reactive species generated in the plasma diffuse through a boundary gas layer which sticks at the material surface. Due to the short lifetime of these species only a small fraction can reach the surface, limiting the surface treatment efficiency...... of approximately 150 dB were introduced vertically to the GFRP surface through a cylindrical waveguide. The water contact angle of the GFRP surface dropped markedly with no ultrasonic irradiation, and tended to decrease furthermore at higher power. Ultrasonic irradiation during the plasma treatment consistently...

  13. Surface Treatment of Polymeric Materials Controlling the Adhesion of Biomolecules

    Directory of Open Access Journals (Sweden)

    Willy Zorzi

    2012-08-01

    Full Text Available This review describes different strategies of surface elaboration for a better control of biomolecule adsorption. After a brief description of the fundamental interactions between surfaces and biomolecules, various routes of surface elaboration are presented dealing with the attachment of functional groups mostly thanks to plasma techniques, with the grafting to and from methods, and with the adsorption of surfactants. The grafting of stimuli-responsive polymers is also pointed out. Then, the discussion is focused on the protein adsorption phenomena showing how their interactions with solid surfaces are complex. The adsorption mechanism is proved to be dependent on the solid surface physicochemical properties as well as on the surface and conformation properties of the proteins. Different behaviors are also reported for complex multiple protein solutions.

  14. Surface Treatment of Polymeric Materials Controlling the Adhesion of Biomolecules

    Science.gov (United States)

    Poncin-Epaillard, Fabienne; Vrlinic, Tjasa; Debarnot, Dominique; Mozetic, Miran; Coudreuse, Arnaud; Legeay, Gilbert; El Moualij, Benaïssa; Zorzi, Willy

    2012-01-01

    This review describes different strategies of surface elaboration for a better control of biomolecule adsorption. After a brief description of the fundamental interactions between surfaces and biomolecules, various routes of surface elaboration are presented dealing with the attachment of functional groups mostly thanks to plasma techniques, with the grafting to and from methods, and with the adsorption of surfactants. The grafting of stimuli-responsive polymers is also pointed out. Then, the discussion is focused on the protein adsorption phenomena showing how their interactions with solid surfaces are complex. The adsorption mechanism is proved to be dependent on the solid surface physicochemical properties as well as on the surface and conformation properties of the proteins. Different behaviors are also reported for complex multiple protein solutions. PMID:24955631

  15. Bond strength of resin-resin interfaces contaminated with saliva and submitted to different surface treatments

    OpenAIRE

    Furuse, Adilson Yoshio; Cunha, Leonardo Fernandes da; Benetti, Ana Raquel; Mondelli, José

    2007-01-01

    The purpose of this study was to investigate the effect of different surface treatments on shear bond strength of saliva-contaminated resin-resin interfaces. Flat resin surfaces were fabricated. In the control group, no contamination or surface treatment was performed. The resin surfaces of the experimental groups were contaminated with saliva and air-dried, and then submitted to: (G1) rinsing with water and drying; (G2) application of an adhesive system; (G3) rinsing and drying, abrasion wit...

  16. Corrosion prevention of magnesium surfaces via surface conversion treatments using ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Jun; Luo, Huimin

    2016-09-06

    A method for conversion coating a magnesium-containing surface, the method comprising contacting the magnesium-containing surface with an ionic liquid compound under conditions that result in decomposition of the ionic liquid compound to produce a conversion coated magnesium-containing surface having a substantially improved corrosion resistance relative to the magnesium-containing surface before said conversion coating. Also described are the resulting conversion-coated magnesium-containing surface, as well as mechanical components and devices containing the conversion-coated magnesium-containing surface.

  17. Towards improved correlations between bitumen properties and rutting resistance of bituminous mixtures - FunDBitS literature review

    Science.gov (United States)

    Batista, Fátima A.; Hofko, Bernhard; De Visscher, Joëlle; Tanghe, Tine; da Costa, Margarida Sá

    2017-09-01

    Bitumen is the most common binder used in the production of bituminous mixtures for road paving, having a fundamental influence on the performance of the pavement. However, it is not yet fully understood which bitumen properties have a significant influence on the behaviour of bituminous mixtures. In this context, the FunDBitS project was developed. Its main objective was to prepare recommendations on the properties of the bitumen to be specified in order to obtain suitable bituminous mixtures, namely in what concerns to its resistance to permanent deformation (rutting), stiffness, low temperature cracking, fatigue cracking and binder/aggregate interaction. In this framework, the research studies that have become internationally available since the BiTVal project were reviewed in order to assess performance-based bitumen characteristics, which may be introduced into bitumen specification standards. This paper specifically presents the main conclusions regarding the properties of bitumen related to the behaviour to permanent deformation of bituminous mixtures. It was concluded that the most promising test is the “non-recoverable creep compliance” (Jnr) from the Multiple Stress Creep and Recovery (MSCR) test method, although Zero/Low Shear Viscosity (ZSV/LSV) by creep or oscillation test method can also give good correlations with permanent deformation of bituminous mixtures.

  18. Increased Biocompatibility and Bioactivity after Energetic PVD Surface Treatments

    Directory of Open Access Journals (Sweden)

    Stephan Mändl

    2009-09-01

    Full Text Available Ion implantation, a common technology in semiconductor processing, has been applied to biomaterials since the 1960s. Using energetic ion bombardment, a general term which includes conventional ion implantation plasma immersion ion implantation (PIII and ion beam assisted thin film deposition, functionalization of surfaces is possible. By varying and adjusting the process parameters, several surface properties can be attuned simultaneously. Extensive research details improvements in the biocompatibility, mainly by reducing corrosion rates and increasing wear resistance after surface modification. Recently, enhanced bioactivity strongly correlated with the surface topography and less with the surface chemistry has been reported, with an increased roughness on the nanometer scale induced by self-organisation processes during ion bombardment leading to faster cellular adhesion processes.

  19. Evaluating the need for surface treatments to reduce crash frequency on horizontal curves.

    Science.gov (United States)

    2013-10-01

    The application of high-friction surface treatments at appropriate horizontal curve locations throughout the : state has the potential to improve driver performance and reduce the number of crashes experienced at : horizontal curves. These treatments...

  20. Technologies for surface-treatment and under water cutting

    International Nuclear Information System (INIS)

    Bach, F.W.; Redeker, C.F.; Versemann, R.; Brueggemann, P.

    2003-01-01

    Technologies for processing surfaces and decomposition of installations under water will be presented and compared in their use for dismantling of nuclear facilities. For the removal of surfaces the dry ice- and the dry ice laser blasting process are examined. Experiences in the use of a 1kW Nd:YAG laser for under water cutting of metals are presented. An assisting tool to choose a suitable process for removing coatings and component's surfaces will be developed. The presented work is part of the progress made in a research project consisting of 11 partners: developers, operators and end-users. (orig.)

  1. Control of surface wettability for inkjet printing by combining hydrophobic coating and plasma treatment

    International Nuclear Information System (INIS)

    Park, Heung Yeol; Kang, Byung Ju; Lee, Dohyung; Oh, Je Hoon

    2013-01-01

    We have obtained a wide range of surface wettabilities of PI substrate for inkjet printing by combining hydrophobic solution coating and O 2 or Ar plasma treatments. Experiments were conducted to investigate the variation in inkjet-printed dot diameters with different surface treatments. The change in chemical and physical characteristics of treated surfaces was evaluated using static contact angle measurements, field emission scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. Only hydrophobic coated surface produces the smallest dot diameter and the largest contact angle. Dot diameter increases and contact angle decreases as the plasma treatment time increases. Since the removal of hydrophobic layer from the surface occurs due to the etching effect of O 2 and Ar plasma during the plasma treatments, F/C ratio decreases with increasing the plasma treatment time. Surface roughness variations are also observed after plasma treatments. The ranges of printed dot sizes for O 2 and Ar plasma treatments are 38 μm–70 μm and 38 μm–92 μm, respectively. Ar plasma treatment shows a wider range of surface wettability because of higher removal rate of the hydrophobic layer. This combination of hydrophobic coating and plasma treatment can offer an effective way to obtain a wide range of surface wettabilities for high quality inkjet-printed patterns. - Highlights: • Hydrophobic coating and plasma treatments were used to control surface wettability. • Inkjet-printed dot diameters increase with O 2 or Ar plasma treatment time. • Contact angles of Ag ink agree well with the variation tendency of dot diameters. • The removal of hydrophobic layer occurs during the plasma treatments. • Ar plasma treatment shows a wider range of surface wettability than O 2 plasma

  2. Room temperature wafer direct bonding of smooth Si surfaces recovered by Ne beam surface treatments

    Science.gov (United States)

    Kurashima, Yuichi; Maeda, Atsuhiko; Takagi, Hideki

    2013-06-01

    We examined the applicability of a Ne fast atom beam (FAB) to surface activated bonding of Si wafers at room temperature. With etching depth more than 1.5 nm, the bonding strength comparable to Si bulk strength was attained. Moreover, we found the improvement of the bonding strength by surface smoothing effect of the Ne FAB. Silicon surface roughness decreased from 0.40 to 0.17 nm rms by applying a Ne FAB of 30 nm etching depth. The bonding strength between surfaces recovered by Ne FAB surface smoothing was largely improved and finally became equivalent to Si bulk strength.

  3. Superhydrophilic surface treatment for thin film NiTi vascular applications

    International Nuclear Information System (INIS)

    Chun, Youngjae; Levi, Daniel S.; Mohanchandra, K.P.; Carman, Gregory P.

    2009-01-01

    A variety of surface treatment methods were evaluated to modify the hydrophilic nature of thin film nitinol (NiTi). It has been suggested that increasing hydrophilicity reduces the prevalence of platelet adhesion and thrombosis in the vascular system. In this study, thin film NiTi was treated with three pretreatments cleaning, buffered oxide etchant (BOE), and BOE/nitric acid (HNO 3 ), followed by one surface treatment. The three surface treatment studied were UV irradiation, thermal treatment, or hydrogen peroxide. Two surface treatments, i.e., thermal at 600 deg. C for 30 min and 30% hydrogen peroxide treatment for 15 h, produced superhydrophilic surfaces, i.e., wetting angle = 0 deg. However, the superhydrophilic surface produced by the thermal treatment also embrittled the thin film due to the relative thickness of the oxide grown. Long term studies in air showed that all surface treatments trend toward hydrophobic natures. However, storage of the surface treated thin film NiTi in Deionized (DI) water preserved even the superhydrophilic surfaces indefinitely.

  4. Dielectric barrier discharge for surface treatment: application to selected polymers in film and fibre form

    International Nuclear Information System (INIS)

    Borcia, G; Anderson, C A; Brown, N M D

    2003-01-01

    In this paper, we report and discuss a surface treatment method, using a dielectric barrier discharge (DBD) of random filamentary type. This offers a convenient, reliable and economic alternative for the controlled modification (so far, largely dependent on surface oxidation) of various categories of material surfaces. Remarkably uniform treatment and markedly stable modified surface properties result over the entire area of the test surfaces exposed to the discharge even at transit speeds simulating those associated with continuous on-line processing. The effects of air-DBD treatment on the surfaces of various polymer films and polymer-based fabrics were studied. The dielectric barrier concerned has been characterized in terms of the energy deposited by the discharge at the processing electrodes and the resultant modifications of the surface properties of the treated samples were investigated using x-ray photoelectron spectroscopy, contact angle/wickability measurement and scanning electron microscopy. The influence of the surface treatment parameters, such as the energy deposited by the discharge, the inter-electrode gap and the treatment time were examined and related to the post-treatment surface characteristics of the materials processed. Relationships between the processing parameters and the properties of the DBD treated samples were thus established. Of the three process variables investigated, the duration of the treatment was found to have a more significant effect on the surface modifications found than did the discharge energy or the inter-electrode gap. Very short air-DBD treatments (fractions of a second in duration) markedly and uniformly modified the surface characteristics for all the materials treated, to the effect that wettability, wickability and the level of oxidation of the surface appear to be increased strongly within the first 0.1-0.2 s of treatment. Any subsequent surface modification following longer treatment (>1.0 s) was less important

  5. Dielectric barrier discharge for surface treatment: application to selected polymers in film and fibre form

    Science.gov (United States)

    Borcia, G.; Anderson, C. A.; Brown, N. M. D.

    2003-08-01

    In this paper, we report and discuss a surface treatment method, using a dielectric barrier discharge (DBD) of random filamentary type. This offers a convenient, reliable and economic alternative for the controlled modification (so far, largely dependent on surface oxidation) of various categories of material surfaces. Remarkably uniform treatment and markedly stable modified surface properties result over the entire area of the test surfaces exposed to the discharge even at transit speeds simulating those associated with continuous on-line processing. The effects of air-DBD treatment on the surfaces of various polymer films and polymer-based fabrics were studied. The dielectric barrier concerned has been characterized in terms of the energy deposited by the discharge at the processing electrodes and the resultant modifications of the surface properties of the treated samples were investigated using x-ray photoelectron spectroscopy, contact angle/wickability measurement and scanning electron microscopy. The influence of the surface treatment parameters, such as the energy deposited by the discharge, the inter-electrode gap and the treatment time were examined and related to the post-treatment surface characteristics of the materials processed. Relationships between the processing parameters and the properties of the DBD treated samples were thus established. Of the three process variables investigated, the duration of the treatment was found to have a more significant effect on the surface modifications found than did the discharge energy or the inter-electrode gap. Very short air-DBD treatments (fractions of a second in duration) markedly and uniformly modified the surface characteristics for all the materials treated, to the effect that wettability, wickability and the level of oxidation of the surface appear to be increased strongly within the first 0.1-0.2 s of treatment. Any subsequent surface modification following longer treatment (>1.0 s) was less important

  6. Titanium Dioxide-Based Antibacterial Surfaces for Water Treatment

    Science.gov (United States)

    The field of water disinfection is gaining much interest since waterborne diseases caused by pathogenic microorganisms directly endanger human health. Antibacterial surfaces offer a new, ecofriendly technique to reduce the harmful disinfection byproducts that form in medical and ...

  7. Laser gas assisted treatment of steel 309: Corrosion and scratch resistance of treated surface

    Science.gov (United States)

    Toor, Ihsan-ul-Haq; Yilbas, B. S.; Ahmed, Junaid; Karatas, C.

    2017-10-01

    Laser gas assisted surface treatment of steel 309 is carried out and the characteristics of the resulting surface are analyzed using the analytical tools. Scanning electron and 3-D optical microscopes are used to assess the morphological and metallurgical changes in the laser treated layer. Energy spectroscopy and X-ray diffraction are carried out to determine the elemental composition and compounds formed on the laser treated surface. The friction coefficient of the laser treated surface is measured using the micro-tribometer and compared to that of the as received surface. The corrosion resistance of the laser treated and as received surfaces is measured incorporating the electrochemical tests. It is found that laser treatment results in a dense layer and formation of nitride compounds at the surface. This enhances the microhardness at the laser treated surface. The friction coefficient attains lower values at the laser treated surface than that corresponding to the as received surface. The corrosion rate of the surface reduces significantly after the laser treatment process, which can be attributed to the passive layer at the surface via formation of a dense layer and nitride compounds in the surface vicinity. In addition, the number of pit sites decreased for the laser treated surface than that of as received surface.

  8. 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.

  9. Time dependent viscoelastic rheological response of pure, modified and synthetic bituminous binders

    Science.gov (United States)

    Airey, G. D.; Grenfell, J. R. A.; Apeagyei, A.; Subhy, A.; Lo Presti, D.

    2016-08-01

    Bitumen is a viscoelastic material that exhibits both elastic and viscous components of response and displays both a temperature and time dependent relationship between applied stresses and resultant strains. In addition, as bitumen is responsible for the viscoelastic behaviour of all bituminous materials, it plays a dominant role in defining many of the aspects of asphalt road performance, such as strength and stiffness, permanent deformation and cracking. Although conventional bituminous materials perform satisfactorily in most highway pavement applications, there are situations that require the modification of the binder to enhance the properties of existing asphalt material. The best known form of modification is by means of polymer modification, traditionally used to improve the temperature and time susceptibility of bitumen. Tyre rubber modification is another form using recycled crumb tyre rubber to alter the properties of conventional bitumen. In addition, alternative binders (synthetic polymeric binders as well as renewable, environmental-friendly bio-binders) have entered the bitumen market over the last few years due to concerns over the continued availability of bitumen from current crudes and refinery processes. This paper provides a detailed rheological assessment, under both temperature and time regimes, of a range of conventional, modified and alternative binders in terms of the materials dynamic (oscillatory) viscoelastic response. The rheological results show the improved viscoelastic properties of polymer- and rubber-modified binders in terms of increased complex shear modulus and elastic response, particularly at high temperatures and low frequencies. The synthetic binders were found to demonstrate complex rheological behaviour relative to that seen for conventional bituminous binders.

  10. Biowaste utilization in the process of co-gasification with bituminous coal and lignite

    International Nuclear Information System (INIS)

    Howaniec, Natalia; Smoliński, Adam

    2017-01-01

    Biowaste utilization in co-gasification with bituminous coal and lignite gives the benefits of stable supplies of a primary energy source – coal and utilization of a zero-emission, waste material (i.e. agriculture waste, sewage sludge, etc.) with higher process efficiency and lower negative environmental impact than biomass or coal gasification, respectively. The main focus of the study presented is co-gasification of bituminous coal or lignite with biowaste to hydrogen-rich gas. The experiments were performed in the laboratory scale fixed-bed reactor installation at 700 and 900 °C. The Hierarchical Clustering Analysis complemented with a color map of studied data were applied in the selection of the optimal operating parameters for biowaste utilization in the co-gasification process based on the experimental data of gasification/co-gasification process as well as physical and chemical properties of fuels tested. The experimental results showed that the carbon conversion rate in co-gasification increased with increasing biomass content in a fuel. The total gas volume and hydrogen volume in co-gasification were higher than the values expected based on the results of the gasification process of the fuels analyzed. - Highlights: • Biowaste co-gasification with bituminous coal/lignite to hydrogen-rich gas. • Steam co-gasification in laboratory scale fixed-bed reactor at 700 and 900 °C. • Hierarchical Clustering Analysis complemented with color map of experimental data. • Carbon conversion increase with increasing biomass content. • The highest total gas and hydrogen volume in co-gasification of C-B20 blend at 900C.

  11. Mineral matter in Spanish bituminous and brown coals. Part 2: mineral matter quantification

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Tarazona, M.R.; Martinez Alonso, A.; Tascon, J.M.D. (Instituto Nacional del Carbon y sus Derivados, Oviedo (Spain))

    1993-05-01

    A number of methods for mineral matter quantification were applied to a set of Spanish coals. Bituminous coals of different rank from the Asturian Central basin and brown coals from Galician basins were studied. Normative analysis was shown to be an adequate procedure for determining the concentrations of individual mineral species. It was found that mineral constituents of Asturian bituminous coals are, in decreasing abundance order, clay minerals (muscovite, kaolinite), quartz and carbonates. In the case of Galician brown coals kaolinite is the most abundant mineral, followed by quartz and pyrite. Extraction with ammonium acetate and oxidation with hydrogen peroxide yielded equivalent values for the concentrations of alkali and alkaline-earth elements bound to organic matter in brown coals. A series of direct and indirect procedures as well as numerical methods for determining the total mineral matter content of coals were compared. Optimum methods for determining the total mineral matter contents of bituminous coals were low-temperature ashing (LTA) and acid demineralisation. The sum of the LTA yield of ammonium acetate-extracted coal and the total concentration of ion-exchanged elements provided the most reliable results for brown coals. Correction formulae from ash yield previously derived for coals from other basins yielded only slightly satisfactory results for the Spanish coals under study. Results obtained evidence the importance of correctly establishing the nature and concentration of clay minerals present in coal. Also, the convenience of carrying out more comprehensive work to unequivocally establish the mineral matter/ash factors for the various types of Spanish coals is suggested. 65 refs., 6 tabs.

  12. Synergistic effect on thermal behavior during co-pyrolysis of lignocellulosic biomass model components blend with bituminous coal.

    Science.gov (United States)

    Wu, Zhiqiang; Wang, Shuzhong; Zhao, Jun; Chen, Lin; Meng, Haiyu

    2014-10-01

    Co-thermochemical conversion of lignocellulosic biomass and coal has been investigated as an effective way to reduce the carbon footprint. Successful evaluating on thermal behavior of the co-pyrolysis is prerequisite for predicting performance and optimizing efficiency of this process. In this paper, pyrolysis and kinetics characteristics of three kinds of lignocellulosic biomass model components (cellulose, hemicellulose, and lignin) blended with a kind of Chinese bituminous coal were explored by thermogravimetric analyzer and Kissinger-Akahira-Sunose method. The results indicated that the addition of model compounds had different synergistic effects on thermal behavior of the bituminous coal. The cellulose showed positive synergistic effects on the thermal decomposition of the coal bituminous coal with lower char yield than calculated value. For hemicellulose and lignin, whether positive or negative synergistic was related to the mixed ratio and temperature range. The distribution of the average activation energy values for the mixtures showed nonadditivity performance. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. A Method to Estimate the Dynamic Displacement and Stress of a Multi-layered Pavement with Bituminous or Concrete Materials

    Directory of Open Access Journals (Sweden)

    Zheng LU

    2014-12-01

    Full Text Available In this research work, a method to estimate the dynamic characteristics of a multilayered pavement with bituminous or concrete materials is proposed. A mechanical model is established to investigate the dynamic displacement and stress of the multi-layered pavement structure. Both the flexible and the rigid pavements, corresponding to bituminous materials and concrete materials, respectively, are studied. The theoretical solutions of the multi-layered pavement structure are deduced considering the compatibility condition at the interface of the structural layers. By introducing FFT (Fast Fourier Transform algorithm, some numerical results are presented. Comparisons of the theoretical and experimental result implied that the proposed method is reasonable in predicting the stress and displacement of a multi-layered pavement with bituminous or concrete materials. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6071

  14. The projects of reducing environmental pollution at the collieries belonging to Petrosani Autonomous Bituminous Coal Administration

    International Nuclear Information System (INIS)

    Arad, V.; Arad, S.; Costinas, B.; Marchis, G.

    1997-01-01

    The economic development in the Jiu Valley, as practised in the mining and processing of bituminous coal, has had a dynamic character without taking into account, however, the harmful impact on the environment. The most severe problem of environmental pollution in the Jiu Valley is that of the pollution of the Jiu River due to the discharge of waste water from the technological processes of mining and processing coal. This paper presents some solutions for reducing this environmental pollution, especially the Jiu water pollution. 1 ref

  15. Investigation of activity release from bituminized intermediate-level waste forms under thermal stresses

    International Nuclear Information System (INIS)

    Kluger, W.; Vejmelka, P.; Koester, R.

    1983-01-01

    To determine the consequences of a fire during fabrication, intermediate storage and transport of bituminized NaNO 3 waste forms, the fractions of plutonium released from the waste forms were assessed. For this purpose, laboratory tests were made with PuO 2 -containing specimens as well as a field test with specimens containing Eu 2 O 3 . By the evaluation of plutonium release in the laboratory and by the determination of the total sodium release and the relative Eu/Na release in the field tests the plutonium release can be deduced from full-scale specimens. The results show that for bituminized waste forms with high NaNO 3 contents (approx. 36 wt%) the average plutonium release obtained in laboratory testing is 15%. In the field tests (IAEA fire test conditions) an average Eu release of 8% was found. These results justify the statement that also for waste forms in open 175 L drum inserts a maximum plutonium release of about 15% can be expected. From the time-dependence of Eu/Na release in the field tests an induction period of 15-20 minutes between the start of testing and the first Na/Eu release can be derived. The maximum differential Na/Eu release occurs after a test period of 45 to 60 minutes duration and after 90 to 105 minutes (tests K2 and K4, respectively); after that time also the highest temperatures in the products are measured. The release values were determined for products in open 175 L drum inserts which in this form are not eligible for intermediate and ultimate storage. For bituminized waste forms in concrete packages (lost concrete shieldings) a delayed increase in temperature to only 70-80 deg. C takes place (4-5 hours after extinction of the fire) if the fire lasts 45 minutes. The concrete package remains intact under test conditions. This means that activity release from bituminized waste forms packaged in this way can be ruled out in the case under consideration. (author)

  16. Assessment of the Remaining Life of Bituminous Layers in Road Pavements

    Directory of Open Access Journals (Sweden)

    Kálmán Adorjányi

    2017-02-01

    Full Text Available In this paper, a mechanistic-empirical approach is presented for the assessment of bearing capacity condition of asphalt pavement layers by Falling Weight Deflectometer measurements and laboratory fatigue tests. The bearing capacity condition ratio was determined using past traffic data and the remaining fatigue life which was determined from multilayer pavement response model. The traffic growth rate was taken into account with finite arithmetic and geometric progressions. Fatigue resistance of layers’ bituminous materials was obtained with indirect tensile fatigue tests. Deduct curve of condition scores was derived with Weibull distribution.

  17. Fixed-bed gasification research using US coals. Volume 13. Gasification of Blind Canyon bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Thimsen, D.; Maurer, R.E.; Pooler, A.R.; Pui, D.; Liu, B.; Kittelson, D.

    1985-05-01

    A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the thirteenth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of Blind Canyon bituminous coal, from July 31, 1984 to August 11, 1984. 6 refs., 22 figs., 20 tabs.

  18. Bioremediation of pesticides in surface soil treatment unit using ...

    African Journals Online (AJOL)

    The manufacturing and use of pesticides has been rising tremendously in India. The waste generated by the pesticide industry has become an environmental problem due to the present insufficient and ineffective waste treatment technology involving physico-chemical and biological treatment. The available data indicates ...

  19. Effect of surface treatments on stress corrosion cracking susceptibility of nickel base alloys

    International Nuclear Information System (INIS)

    Iwanami, Masaru; Kaneda, Junya; Tamako, Hiroaki; Hato, Hisamitsu; Takamoto, Shinichi

    2009-01-01

    Effect of surface treatment on SCC susceptibility of Ni base alloys was investigated. Cracks were observed in all grinding specimens in a creviced bent beam (CBB) test. On the other hand, no cracks occurred in shot peening (SP), water jet peening (WJP) specimens. It was indicated that these surface treatments effectively reduced the SCC susceptibility of nickel-base alloys. As a result of a residual stress test, the surface of specimens with grinding had high tensile residual stress. However, SP and WJP improved surface residual stress to compressive stress. The depth of the compressive effect of WJP was almost the same as that of SP. However, the surface hardness of WJP specimens differed from that of SP and it was found that WJP had less impact on surface hardening. This difference was consistent with their surface microstructures. The surface of SP specimens had clearly the deformation region, but the surface of WJP specimens was localized. (author)

  20. Surface science in hernioplasty: The role of plasma treatments

    Science.gov (United States)

    Nisticò, Roberto; Magnacca, Giuliana; Martorana, Selanna

    2017-10-01

    The aim of this review is to clarify the importance of surface modifications induced in biomaterials for hernia-repair application. Starting from the pioneering experiences involving proto-materials as ancient prosthesis, a historical excursus between the biomaterials used in hernioplasty was realized. Subsequently, after the revolutionary discovery of stereoregular polymerization followed by the PP application in the biomedical field performed by the surgeon F. Usher, a comparative study on different hernia-repair meshes available was realized in order to better understand all the outstanding problems and possible future developments. Furthermore, since many unsolved problems on prosthetic devices implantation are linked to phenomena occurring at the interface between the biomaterials surface and the body fluids, the importance of surface science in hernioplasty was highlighted and case studies of new surface-modified generations of prosthesis presented. The results discussed in the following evidence how the surface study are becoming increasingly important for a proper knowledge of issues related to the interaction between the living matter and the artificial prostheses.

  1. Improving Hydrophobicity of Glass Surface Using Dielectric Barrier Discharge Treatment in Atmospheric Air

    International Nuclear Information System (INIS)

    Fang Zhi; Qiu Yuchang; Wang Hui; Kuffel, E

    2007-01-01

    Non-thermal plasmas under atmospheric pressure are of great interest in industrial applications, especially in material surface treatment. In this paper, the treatment of a glass surface for improving hydrophobicity using the non-thermal plasma generated by dielectric barrier discharge (DBD) at atmospheric pressure in ambient air is conducted, and the surface properties of the glass before and after the DBD treatment are studied by using contact angle measurement, surface resistance measurement and wet flashover voltage tests. The effects of the applied voltage and time duration of DBD on the surface modification are studied, and the optimal conditions for the treatment are obtained. It is found that a layer of hydrophobic coating is formed on the glass surface after spraying a thin layer of silicone oil and undergoing the DBD treatment, and the improvement of hydrophobicity depends on DBD voltage and treating time. It seems that there exists an optimum treating time for a certain applied voltage of DBD during the surface treatment. The test results of thermal aging and chemical aging show that the hydrophobic layer has quite stable characteristics. The interaction mechanism between the DBD plasma and the glass surface is discussed. It is concluded that CH 3 and large molecule radicals can react with the radicals in the glass surface to replace OH, and the hydrophobicity of the glass surface is improved accordingly

  2. Surface Characterization and Cell Adhesion of Different Zirconia Treatments: An in vitro Study.

    Science.gov (United States)

    Nassif, Wadih; Rifai, Mohamad

    2018-02-01

    The aim of this study was to characterize the surface of zirconia subjected to different treatments and evaluate its effect on cell adhesion and proliferation. A total of 80 zirconia disks were divided into four groups (n = 20) according to the surface treatments used: group I: as-sintered (AS), no surface treatment applied; group II: abrasion treatment applied using Rocatec (ROC; 3M ESPE) system with silica-coated alumina powder of grit size 110 μm; group III: erbium, chromium:yttrium, scandium, gallium, garnet (Er, Cr:YSGG) laser (LAS; BIOLASE) was used at a frequency of 20 Hz and output power of 3 W; and group IV: specimens were subjected to the selective infiltration etching (SIE) technique. Surface characterization was evaluated for the different groups (roughness, hardness, and morphology), and cell behavior (adhesion and proliferation) was tested (a = 0.05). The ROC group reported a significant increase in surface roughness (2.201 ± 0.352) and Vickers hardness (1758 ± 16.6) compared with the other surface treatments. The SIE surface-treated group reported a significantly higher number of cells (64.5 ± 2.6 and 53.5 ± 2.2 respectively) compared with the other surface-treated groups. The SIE is a promising surface treatment for zirconia that significantly enhances cell adhesion and osseointegration. The SIE treatment of zirconia implants may help in a faster and better osseointegration.

  3. Polyfunctional Modifiers for Bitumen and Bituminous Materials with High Performance

    Directory of Open Access Journals (Sweden)

    Alim Feizrakhmanovich Kemalov

    2018-01-01

    Full Text Available Over the last decade increase in capacity and the intensity of vehicular traffic has increased manifoldly, including heavy trucks, super singles, and higher tire pressures, resulting in significant increase of dynamic loads on the road surface which in turn lead to high quality requirements for bitumen in order to avoid premature wear and failure of asphalt concrete pavements. One of the possibilities to increase the quality of bitumen is to use special additives and modifiers that can provide a high adhesion to mineral filler and inhibit the aging and degradation processes in the asphalt coating. To achieve this, in the present study composite modifiers based on bisimidazolines derivatives were synthesized. The developed polyfunctional modifier (PFM of complex action provides enhanced thermal stability, significantly improves the adhesion between bitumen binder and aggregates, and also improves the physical-mechanical properties of the asphalt concrete. Based on the test results it is recommended to use the synthesized samples of the PFM additive with complex action in asphalt mixtures for road paving.

  4. Air powder abrasive treatment as an implant surface cleaning method: a literature review

    NARCIS (Netherlands)

    Tastepe, C.S.; van Waas, R.; Liu, Y.; Wismeijer, D.

    2012-01-01

    OBJECTIVE: To evaluate the air powder abrasive treatment as an implant surface cleaning method for peri-implantitis based on the existing literature. MATERIALS AND METHODS: A PubMed search was conducted to find articles that reported on air powder abrasive treatment as an implant surface cleaning

  5. The HIE-ISOLDE Superconducting Cavities: Surface Treatment and Niobium Thin Film Coating

    CERN Document Server

    Lanza, G; Ferreira, L M A; Gustafsson, A E; Pasini, M; Trilhe, P; Palmieri, V

    2010-01-01

    CERN has designed and prepared new facilities for the surface treatment and niobium sputter coating of the HIE-ISOLDE superconducting cavities. We describe here the design choices, as well as the results of the first surface treatments and test coatings.

  6. Biomarker geochemistry of bituminous shale sequence and crude oil in the Ereǧli-Bor Basin (Konya-Niǧde), Central Anatolia, Turkey

    Science.gov (United States)

    Kara-Gulbay, Reyhan; Erdogan, Mert; Korkmaz, Sadettin; Kadinkiz, Gökhan

    2016-04-01

    In the Ereǧli-Bor Basin (Konya-Niǧde), Central Anatolia, bituminous shale sequence with thickness ranging between 72 and 160 m occurs in lacustrine deposits of Upper Miocene-Pliocene age. The live oil has also been observed in this bituminous shale sequence. Rock-Eval/TOC, GC and GC-MS analyses were conducted on selected bituminous shale samples from four borehole (key-12/1, key-12/2, key-12/3 key-12/4) and one crude oil sample from a borehole (key-12/2) in the basin. In this study, organic matter type, maturity and depositional environment of bituminous shale are evaluated and the origin of crude oil is determined by the bituminous shale-crude oil correlation. The total organic carbon (TOC) values of the bituminous shale samples range from 1.21-13.98 wt% with an average TOC value of 4.75wt%. The bituminous shale sequence is characterized by high HI (127-662 mg HC/g TOC) and low OI (7-50 mgCO2/TOC). Tmax varies from 332-419ᵒC. Very low Pr/Ph ratios of bituminous shale (0.09-0.22) are indicative of anoxic depositional conditions. C27 is dominate sterane for bituminous shale and crude oil samples with C27>C29>C28. Normal steranes are more dominant compare to iso- and diasteranes. Ouite high sterane/hopane ratios (1.14-2.70) indicate dominant algal organic matter input for bituminous shale and source rock of crude oil. C31R/hopane ratio for bituminous shale and crude oil samples are very low (0.09-0.13) and these ratio show a lacustrine depositional envirronment for bituminous shale and source rock of crude oil. Sterane and terpane distributions of bituminous shale and crude oil are very similar. A very good correlation in terms of biomarker between bituminous shale and crude oil samples indicate that source rock of crude oil is bituminous shale. The 22S/(22R + 22S) C32 homohopane ratios of bituminous shale and crude oil samples are found to be 0.56 and 0.61, indicating that homohopane isomerization has attained equilibrium and bituminous shale and crude oil are

  7. Water evaporation from substrate tooth surface during dentin treatments.

    Science.gov (United States)

    Kusunoki, Mizuho; Itoh, Kazuo; Gokan, Yuka; Nagai, Yoshitaka; Tani, Chihiro; Hisamitsu, Hisashi

    2011-01-01

    The purpose of this study was to evaluate changes in the quantity of water evaporation from tooth surfaces. The amount of water evaporation was measured using Multi probe adapter MPA5 and Tewameter TM300 (Courage+Khazaka Electric GmbH, Köln, Germany) after acid etching and GM priming of enamel; and after EDTA conditioning and GM priming of dentin. The results indicated that the amount of water evaporation from the enamel surface was significantly less than that from the dentin. Acid etching did not affect the water evaporation from enamel, though GM priming significantly decreased the evaporation (83.48 ± 15.14% of that before priming). The evaporation from dentin was significantly increased by EDTA conditioning (131.38 ± 42.08% of that before conditioning) and significantly reduced by GM priming (80.26 ± 7.43% of that before priming). It was concluded that dentin priming reduced water evaporation from the dentin surface.

  8. Protection of Oil Casing Tube Steel via Surface Treatment in China: a Literature Review

    Science.gov (United States)

    Zou, Jiaojuan; Lin, Naiming; Qin, Lin; Tang, Bin; Xie, Faqin

    2013-04-01

    Oil casing tube is the foundation member of an oil well and it plays an important role in oil exploration and exploitation. The oil casing tubes are prone to failure induced by corrosion and wear during applications. Based on the fact that the damages caused by corrosion and wear are first generated on the surface of oil casing tube, adopting an appropriate surface treatment technology would be a promising approach to protect itself from deterioration. Surface treatments can fabricate protective layers with different composition or structure from the substrate. This paper reviewed the existing literatures about the protection of oil casing tube steel via surface treatment in China.

  9. Improved surface treatment of the superconducting TESLA cavities

    CERN Document Server

    Lilje, L; Benvenuti, Cristoforo; Bloess, D; Charrier, J P; Chiaveri, Enrico; Ferreira, L; Losito, R; Matheisen, A; Preis, H; Proch, D; Reschke, D; Safa, H; Schmüser, P; Trines, D; Visentin, B; Wenninger, Horst

    2004-01-01

    The proposed linear electron-positron collider TESLA is based on 1.3 GHz superconducting niobium cavities for particle acceleration. For a centre-of-mass energy of 500 GeV, an accelerating field of 23.4 MV/m is required which is reliably achieved with a niobium surface preparation by chemical etching. An upgrade of the collider to 800 GeV requires an improved cavity preparation technique. In this paper, results are presented on single-cell cavities which demonstrate that fields of up to 40 MV/m are accessible by electrolytic polishing of the inner surface of the cavity.

  10. INFLUENCE OF AISI 316Ti STAINLESS STELL SURFACE TREATMENT ON PITTING CORROSION IN VARIOUS SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Pavol Fajnor

    2010-12-01

    Full Text Available Investigation of the surface treatment effect on the resistance of AISI 316Ti stainless steel to pitting corrosion is presented in this paper. The grinded surfaces without additional chemical treatment, grinded and pickled, grinded, pickled and passivated surfaces are tested. The corrosion tests are carried out by exposition in solution which evoke pitting and by electrochemical cyclic potential - sweep method. According to the results the surface treatment has a great influence on the resistance of the tested material to pitting. It is not possible to estimate the best surface treatment because behavior of AISI 316Ti stainless steel with different surface state depends on the mechanism of corrosion processes which vary in the used experimental methods.

  11. Corrosion Resistance of Steel 45 Subjected to Electromechanical Treatment and Surface Plastic Deformation

    Science.gov (United States)

    Dudkina, N. G.

    2018-01-01

    The corrosion properties of normalized steel 45 are studied after a combined hardening of its surface layer, which consists of electromechanical treatment and surface plastic deformation (EMT + SPD). The effect of different aggressive environments on the structure, microhardness and corrosion rate of the hardened surface layer is determined.

  12. Natural analogues of bitumen and bituminized radioactive waste

    International Nuclear Information System (INIS)

    Hellmuth, K.-H.

    1989-07-01

    Occurrences of natural bitumen provide possibilities to identify and assess materials, processes, phenomena and conditions in nature which can serve as model cases valid also with respect to a final repository. Natural bitumens meet the basic requirements for use as natural analogues. In natural sites, processes of bitumen formation and degradation often work simultaneously. The major processes are thermal alteration, evaporation, reaction with water, biodegradation, oxidation, weathering and radiation degradation. Progress in analytical organic geochemistry made during recent years has enabled a deeper understanding of the structural and compositional effects of these processes on bitumen. This is necessary in natural analogue applications. The time scales involved in degradation processes, as observed in natural occurrences, exceed the time scales dictated by the half-lives of most important fission products in low and medium level waste by orders of magnitude. Only exposure to the weather at the surface leads to a more rapid destruction of bitumen. Trace metals in bitumen arenot released until the matrix is completely destroyed. Products of radiation degradation and weathering of bitumen are able, to a certain degree, to delay migration of the metal ions released. Impregnation with bitumen may effectively reduce the microbial decomposition of easily destructable organic waste components, as can be deduced on the basis of the excellent preservation of fossils observed in bitumen. The complexity of all the natural sites described requires extensive understanding of the origin and kind of organic material in bitumen, its maturation, migration, alteration and degradation and of the geological and tectonic evolution of the site. The latter is used for establishing the time scale

  13. Effects of heat treatments on surface roughness of silicon nitride ceramics

    International Nuclear Information System (INIS)

    Nakano, T.; Kinemuchi, Y.; Ishizaki, K.

    1999-01-01

    Silicon nitride ceramics were sintered by Pulsed Electric Current Sintering (PECS) method. Sintered Si 3 N 4 bodies were coated by copper, and heat treated at 1200 deg C for 1 hour in air. After the Cu coating and heat treatment, the ground Si 3 N 4 surface was oxidized, its duration was calculated from intensities obtained by an Electron Probe Micro Analyzer. The oxidized surfaces became smoother by heat treatment as the Cu coating period increases. The oxidation for smoothening treatments of silicon nitride ceramics requires the eutectic mixture of copper oxide and silicon oxide formed by the heat treatment on the ground surface covered by Cu before the treatment. Less nitrogen atoms on the Si 3 N 4 surface is necessary in order to smoothen the Si 3 N 4 surface. Copyright (1999) AD-TECH - International Foundation for the Advancement of Technology Ltd

  14. Ambient plasma treatment of silicon wafers for surface passivation recovery

    Science.gov (United States)

    Ge, Jia; Prinz, Markus; Markert, Thomas; Aberle, Armin G.; Mueller, Thomas

    2017-08-01

    In this work, the effect of an ambient plasma treatment powered by compressed dry air on the passivation quality of silicon wafers coated with intrinsic amorphous silicon sub-oxide is investigated. While long-time storage deteriorates the effective lifetime of all samples, a short ambient plasma treatment improves their passivation qualities. By studying the influence of the plasma treatment parameters on the passivation layers, an optimized process condition was identified which even boosted the passivation quality beyond its original value obtained immediately after deposition. On the other hand, the absence of stringent requirement on gas precursors, vacuum condition and longtime processing makes the ambient plasma treatment an excellent candidate to replace conventional thermal annealing in industrial heterojunction solar cell production.

  15. Influence of surface treatment on the oxidation behavior of zirconium and zircaloy-4

    International Nuclear Information System (INIS)

    Costa, I.; Ramanathan, L.V.

    1986-01-01

    The influence of fluoride concentration in surface treatment solutions on the oxidation behavior of Zr and Zircaloy-4 in the temperature range 350-760 0 C have been studied by means of thermogravimetric analysis. Two solutions containing different concentrations of hydrofluoric acid have been used for surface treatments, following which surface roughness measurements were also carried out. The influence of fluoride ion concentration on oxidation behavior has been found to be significant at higher temperatures. (Author) [pt

  16. Surface activation of dyed fabric for cellulase treatment.

    Science.gov (United States)

    Schimper, Christian B; Ibanescu, Constanta; Bechtold, Thomas

    2011-10-01

    Surface activation of fabric made from cellulose fibres, such as viscose, lyocell, modal fibres and cotton, can be achieved by printing of a concentrated NaOH-containing paste. From the concentration of reducing sugars formed in solution, an increase in intensity of the cellulase hydrolysis by a factor of six to eight was observed, which was mainly concentrated at the activated parts of the fabric surface. This method of local activation is of particular interest for modification of materials that have been dyed with special processes to attain an uneven distribution of dyestuff within the yarn cross-section, e.g., indigo ring-dyed denim yarn for jeans production. Fabrics made from regenerated cellulose fibres were used as model substrate to express the effects of surface activation on indigo-dyed material. Wash-down experiments on indigo-dyed denim demonstrated significant colour removal from the activated surface at low overall weight loss of 4-5%. The method is of relevance for a more eco-friendly processing of jeans in the garment industry. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Evaluation of Mechanical Property of Carbon Fiber/Polypropylene Composite According to Carbon Fiber Surface Treatment

    International Nuclear Information System (INIS)

    Han, Song Hee; Oh, Hyun Ju; Kim, Seong Su

    2013-01-01

    In this study, the mechanical properties of a carbon fiber/polypropylene composite were evaluated according to the carbon fiber surface treatment. Carbon fiber surface treatments such as silane coupling agents and plasma treatment were performed to enhance the interfacial strength between carbon fibers and polypropylene. The treated carbon fiber surface was characterized by XP S, Sem, and single-filament tensile test. The interlaminar shear strength (Ilks) of the composite with respect to the surface treatment was determined by a short beam shear test. The test results showed that the Ilks of the plasma-treated specimen increased with the treatment time. The Ilks of the specimen treated with a silane coupling agent after plasma treatment increased by 48.7% compared to that of the untreated specimen

  18. The effect of surface treatment on the microstructure of the skin of concrete

    Science.gov (United States)

    Sadowski, Łukasz; Stefaniuk, Damian

    2018-01-01

    The aim of this study is to better understand the heterogeneity and microstructural properties of the skin of concrete. The microstructural evaluation of the skin of concrete was performed using X-ray micro computed tomography (micro-CT). The concrete surface was treated using four methods, due to which different surfaces were obtained, i.e. a raw surface, a surface formed after contact with formwork, a grinded surface and also a shotblasted surface. The results of the pore structure obtained from the micro-CT images were used to assess the influence of selected surface treatment method on the nature of the skin of concrete. It was shown that the thickness and unique nature of the skin of concrete differ for various surface treatment methods.

  19. Feasibility study of producing lump fuel using oil-bituminous sands

    Energy Technology Data Exchange (ETDEWEB)

    Moldybaev, A.B.; Ermagambetov, B.T.; Mamraeva, K.M.; Shin, R.G.; Bakirova, R.K. (Institut Organicheskogo Sinteza i Uglekhimii AN KazSSR (USSR))

    1991-04-01

    Describes production of lump fuel by briquetting and coking different mixtures of non-caking coal with coal preparation sludge and bitumen extracted from oil sands. The coal used was from the Shubarkol'sk coal deposit (USSR); the sludge was from the Saburkhanskaya preparation plant. Properties and composition of oil-bituminous sands and of bitumen to be used as binder are given. Technological details of the briquetting and coking processes are provided. Results show that briquets produced from mixtures of coal and oil-bituminous sands can only be used as a high-ash lump fuel, which cannot be further processed into semicoke. Experiments were carried out briquetting coal or coke, sludge and 6-8% bitumen extracted from the sands, varying coal or coke grain fractions and composition of the mixture. An increased briquet strength was found after using the vacuum-distilled 300-350 C bitumen fraction. Briquets from this non-caking coal with bitumen binder are regarded as ecologically clean fuel. 5 refs.

  20. THE HISTORY OF EXPLORATION AND EXPLOITATION OF BITUMINOUS AND KEROGENOUS DEPOSITS IN CROATIA

    Directory of Open Access Journals (Sweden)

    Berislav Šebečić

    1995-12-01

    Full Text Available It is assumed thal the first known sedimens of natural bitumen or asphalt in coastal Croatia were exploited as the early moddle ages. Yet authenticated written documents about Vinišće near Trogir derive from no earlier than 1628, about Vrgorac/Paklina from only 1753. By the end of the 18th century, many deposits were discovered in Dalmatia, but it was Škrip on the Island of Brač and Suhi Dolac that were important. The earliest known deposits and occurrences of kerogenous rocks, or bituminous or oil shales, are mentioned as stone or fossil coal in Sovinjak, in the upper course of the River Mirna, and in Rebići in Istria; near Sinj, Slivno not far from the River Neretva, Mirta and near Nerežišće on the Island uf Brač. All if these were well known and described in 1804, while Sovinjak was mentioned in the 16th century. In the article, some of new information derived from mining and geological research into bituminous and kerogenous sediments and deposits are provided (the paper is published in Croatian.

  1. Isotopic variations in the nitrogen of natural humic and bituminous organic substances

    International Nuclear Information System (INIS)

    Stiehl, G.; Lehmann, M.

    1980-01-01

    delta 15 N-values and nitrogen contents of a series of humic and bituminous organic sediments of different ranks were determined. The change of the isotopic abundance of nitrogen was investigated during heating in model experiments, using a gas flame coal. In the case of humic carbon coals the relative nitrogen contents vary from 0.8 to 1.4% and the delta 15 N-values from + 3.5 to + 6.3 parts per thousand increasing from the brown coal to anthracite ranks. During the coalification process both the delta 15 N-values and the relative nitrogen contents do not vary continuously with the rank, but pass through maxima and minima. Model experiments using a gas flame coal show the same trend. Nitrogen with delta 15 N-values of + 2.8 or -7 parts per thousand was released in pyrolysis experiments, applying a gas flame coal and a steam coal at temperatures of 650 and 1000 0 C, respectively. The investigated bituminous sediments yielded relative amounts of 0.1 to 0.8% with delta 15 N-values of + 4.2 to + 10.7 parts per thousand. The obtained results are discussed with respect to the elucidation of nitrogen genesis in natural gas deposits. (author)

  2. Assessing radioactive concentrates and waste vapor condensate in solidifying radioactive wastes by bituminization

    International Nuclear Information System (INIS)

    Tibensky, L.; Krejci, F.; Breza, M.; Timulak, J.; Hladky, E.

    1986-01-01

    A brief overview is presented of chemical and radiochemical methods used in the world for the analysis of the concentrate of liquid radioactive wastes from nuclear power plants destined for bituminization. Most methods are also suitable for an analysis of the condensate of waste vapors produced in bituminization. The methods of analysis of the radioactive concentrate from the V-1 nuclear power plant in Jaslovske Bohunice and of the waste vapors condensate were developed and tested in practice. Gross gamma activity was measured using a well-type Na(Tl) scintillation detector, the content of radionuclides was determined using semiconductor Ge(Li) spectrometry. The concentration of boric acid in the concentrate was determined by titration with mannite; in the condensate, using spectrophotometry with curcumine. The content of nitrates in both the concentrate and the condensate was determined spectrophotometrically using salicylic acid, the content of nitrites was determined by spectrophotometry using sulfanilic acid and α-naphthylamine. Carbonates and chlorides were determined by titration, sodium and potassium by flame photometry. The content of organic acids was measured by gravimetry of extracted methyl esters, the content of surfactants by spectrophotometry. Infrared spectrophotometry was used in determining hydrocarbons in the waste vapor condensate. The measured value range and the measurement errors are shown for each method. (A.K.)

  3. Reuse of bituminous pavements: A mini-review of research, regulations and modelling.

    Science.gov (United States)

    Anthonissen, Joke; Van den Bergh, Wim; Braet, Johan

    2017-04-01

    Bituminous pavement can be recycled - even multiple times - by reusing it in new bituminous mixtures. If the mechanical properties of the binder get worse, this reclaimed asphalt is often used in the sub-structure of the road. Apparently, up till now, no end-of-life phase exists for the material. Actually, defining the end-of-life and the end-of-waste stage of a material is important for life cycle assessment modelling. Various standards and scientific studies on modelling life cycle assessment are known, but the crucial stages are not yet defined for reclaimed asphalt pavement. Unlike for iron, steel and aluminium scrap, at this moment, no legislative end-of-waste criteria for aggregates are formulated by the European Commission. More research is necessary in order to develop valuable end-of-life criteria for aggregates. This contribution is a mini-review article of the current regulations, standards and studies concerning end-of-life and end-of-waste of reclaimed asphalt pavement. The existing methodology in order to define end-of-waste criteria, a case study on aggregates and the argumentation used in finished legislative criteria are the basis to clarify some modelling issues for reclaimed asphalt material. Hence, this contribution elucidates the assignment of process environmental impacts to a life cycle stage as defined by EN15804, that is, end-of-life stage (C) and the supplementary information Module D with benefits and loads beyond the system boundary.

  4. Application of the cementitious grouts on stability and durability of semi flexible bituminous mixtures

    Science.gov (United States)

    Karami, Muhammad

    2017-11-01

    This paper describes the results of laboratory test for a high durability semi flexible bituminous mixtures (SFBM). The SFBM consists of an open asphalt structure where a high strength mortar is penetrated into the air voids of the bituminous mixtures. The SFBM combines the cement concrete's strength and the asphalt material flexibility. The objective of this study is to involve in the determination of stability and durability of SFBM by located the position of the specimen on an exposed area for 7, 90, 180 and 240 days. The performance of the SFBM was assessed using Marshall and wheel tracking apparatus. Total 18 specimens were prepared and examined for both of test. The Marshall specimens were cylindrical with dimension of 10.16 cm in diameter and 6.35 cm in high. For wheel tracking test, the specimens consisted of slabs with dimension of 30 cm in length, 30 cm in width and 5 cm in height. The results indicated that the first durability index and second durability index increased significantly. For Marshall test, the first and second durability index increased about 0.9% per day and 52.3%, respectively. However, for wheel tracking test, the first and second durability index increased about 1.9% per day and 119%, respectively.

  5. Adapting palynological preparation methods in subbituminous and bituminous coals from Colombia to improve palynofacies and hydrocarbon source rock evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Blandon, Astrid; Arango, Fredy [Facultad de Minas, Universidad Nacional de Colombia, Calle 65, 78-28, Medellin (Colombia); Parra, Norberto [Facultad de Ciencias, Universidad Nacional de Colombia, Calle 59A, 63-020, Medellin (Colombia); Gorin, Georges E. [Dpmt. Geology-Paleontology, University of Geneva, 13 rue des Maraichers, 1205 Geneva (Switzerland)

    2008-01-21

    Apart from their potential as fossil fuel, bituminous and subbituminous coals in Colombia may prove to be potential source rocks for the generation of hydrocarbons. The assessment of such properties requires the combination of petrographic and palynofacies studies. The latter correspond to the microscopic investigation in transmitted white and reflected UV lights of sedimentary organic matter insoluble in organic and inorganic solvents. To date, mineral acid and Schulze methods have failed to produce good samples of palynofacies constituents from Cenozoic coals in Colombia, so that the latter method had to be modified. The main modifications consist in adapting the KClO{sub 3} to HNO{sub 3} ratio in the Schulze mixture and introducing two extra phases of oxidation with NaOH and NH{sub 4}OH, which permit the washing off of humic substances. This method yields the full spectrum of palynofacies constituents, which are not destroyed or damaged by the alkali treatment. Neither is their fluorescence colour affected by the initial acid treatment. On the contrary, the particle fluorescence intensity tends to increase because of the dissolution of humic acids, making their identification easier. The achievements of the modified method are threefold: 1) it permits the correlation between macerals in petrographic polished sections and their equivalent in palynofacies slides, making the two methods complementary; 2) palynofacies provides a better identification of sporomorphs than petrography, resulting in better paleoenvironmental interpretations; 3) palynofacies tend to give a more precise quantitative evaluation of the liptinitic constituents, and consequently, of the coal hydrocarbon generation potential. (author)

  6. Treatment of surfaces with low-energy electrons

    Energy Technology Data Exchange (ETDEWEB)

    Frank, L., E-mail: ludek@isibrno.cz [Institute of Scientific Instruments of the CAS, v.v.i., Královopolská 147, 61264 Brno (Czech Republic); Mikmeková, E. [Institute of Scientific Instruments of the CAS, v.v.i., Královopolská 147, 61264 Brno (Czech Republic); FEI Company, Achtseweg Noord 5, 5651 GG Eindhoven (Netherlands); Lejeune, M. [LPMC – Faculte des Sciences d’Amiens, Universite de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex 2 (France)

    2017-06-15

    Highlights: • Using proper irradiation parameters, adsorbed hydrocarbons are released from surfaces. • Slow electrons remove hydrocarbons instead of depositing carbon. • Prolonged irradiation with very slow electrons does not create defects in graphene. - Abstract: Electron-beam-induced deposition of various materials from suitable precursors has represented an established branch of nanotechnology for more than a decade. A specific alternative is carbon deposition on the basis of hydrocarbons as precursors that has been applied to grow various nanostructures including masks for subsequent technological steps. Our area of study was unintentional electron-beam-induced carbon deposition from spontaneously adsorbed hydrocarbon molecules. This process traditionally constitutes a challenge for scanning electron microscopy practice preventing one from performing any true surface studies outside an ultrahigh vacuum and without in-situ cleaning of samples, and also jeopardising other electron-optical devices such as electron beam lithographs. Here we show that when reducing the energy of irradiating electrons sufficiently, the e-beam-induced deposition can be converted to e-beam-induced release causing desorption of hydrocarbons and ultimate cleaning of surfaces in both an ultrahigh and a standard high vacuum. Using series of experiments with graphene samples, we demonstrate fundamental features of e-beam-induced desorption and present results of checks for possible radiation damage using Raman spectroscopy that led to optimisation of the electron energy for damage-free cleaning. The method of preventing carbon contamination described here paves the way for greatly enhanced surface sensitivity of imaging and substantially reduced demands on vacuum systems for nanotechnological applications.

  7. Prospects of DLC coating as environment friendly surface treatment process.

    Science.gov (United States)

    Kim, S W; Kim, S G

    2011-06-01

    After first commercialization in 90's, the applications of diamond-like carbon (DLC) have been significantly expanded to tool, automobile parts, machineries and moulds to enhance wear and friction properties. Although DLC has many advantages like high hardness, low friction electrical insulating and chemical stability and has the possible market, its application in the field is still very limited due to the gaps of understanding between end-user and developer of its advantage of costing. Recently, one of the most popular issues in the surface modification is providing the long lasting super-hydrophilic or -hydrophobic properties on the material surface for the outdoor usage. A lot of material loss is caused due to water corrosion which has to do with the flow and contacts of water like fuel cell separator and air conditioner parts. The consequence of development of functional surface based on the hydrophilic or hydrophobic design for the important parts would be really helpful for materials to be cleaner and more energy effective. Here, we first reviewed the DLC technology and then examined the kind of surface modification as well as its merits and disadvantage. We also looked at how we can improve super-hydrophilic and super hydrophobic for the DLC coating layer as well as current status of technology and arts of DLC. In the end, we would like to suggest it as one of the environmental friendly industrial technology. Copyright © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  8. Low-energy particle treatment of GaAs surface

    International Nuclear Information System (INIS)

    Pincik, E.; Ivanco, J.; Brunner, R.; Jergel, M.; Falcony, C.; Ortega, L.; Kucera, J. M.

    2002-01-01

    The paper presents results of a complex study of surface properties of high-doped (2x10 18 cm -3 ) and semi-insulating GaAs after an interaction with the particles coming from low-energy ion sources such as RF plasma and ion beams. The virgin samples were mechano-chemically polished liquid-encapsulated Czochralski-grown GaAs (100) oriented wafers. The crystals were mounted on the grounded electrode (holder). The mixture Ar+H 2 as well as O 2 and CF 4 were used as working gases: In addition, a combination of two different in-situ exposures was applied, such as e.g. hydrogen and oxygen. Structural, electrical and optical properties of the exposed surfaces were investigated using X-ray diffraction at grazing incidence, quasi-static and high-frequency C-V curve measurements, deep-level transient spectroscopy, photo-reflectance, and photoluminescence. Plasma and ion beam exposures were performed in a commercial RF capacitively coupled plasma equipment SECON XPL-200P and a commercial LPAI device, respectively. The evolution of surface properties as a function of the pressure of working gas and the duration of exposure was observed. (Authors)

  9. Organoselenium Surface Modification of Stainless Steel Surfaces To Prevent Biofouling in Treatment of Space Wastestreams Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this work is to quantify the reduction of biofilm formation in a water distribution system resulting from an organoselenium surface coating on...

  10. Aggregate strength for bituminous surfacings for low volume roads: a heavy vehicle simulator experience

    CSIR Research Space (South Africa)

    Paige-Green, P

    2004-09-01

    Full Text Available This paper discusses an investigation using the CSIR Transportek Heavy Vehicle Simulator (HVS) to determine the impact of using aggregates softer than specified in chip seals and to propose possible relaxations in the currently specified strength...

  11. Assessment of Surface Area Characteristics of Dental Implants with Gradual Bioactive Surface Treatment

    Science.gov (United States)

    Czan, Andrej; Babík, Ondrej; Miklos, Matej; Záušková, Lucia; Mezencevová, Viktória

    2017-10-01

    Since most of the implant surface is in direct contact with bone tissue, shape and integrity of said surface has great influence on successful osseointegration. Among other characteristics that predetermine titanium of different grades of pureness as ideal biomaterial, titanium shows high mechanical strength making precise miniature machining increasingly difficult. Current titanium-based implants are often anodized due to colour coding. This anodized layer has important functional properties for right usage and also bio-compatibility of dental implants. Physical method of anodizing and usage of anodizing mediums has a significant influence on the surface quality and itself functionality. However, basic requirement of the dental implant with satisfactory properties is quality of machined surface before anodizing. Roughness, for example, is factor affecting of time length of anodizing operation and so whole productivity. The paper is focused on monitoring of surface and area characteristics, such as roughness or surface integrity after different cutting conditions of miniature machining of dental implants and their impact on suitability for creation of satisfactory anodized layer with the correct biocompatible functional properties.

  12. Surface fuel loadings within mulching treatments in Colorado coniferous forests

    Science.gov (United States)

    Mike A. Battaglia; Monique E. Rocca; Charles C. Rhoades; Michael G. Ryan

    2010-01-01

    Recent large-scale, severe wildfires in the western United States have prompted extensive mechanical fuel treatment programs to reduce potential wildfire size and severity. Fuel reduction prescriptions typically target non-merchantable material so approaches to mechanically treat and distribute residue on site are becoming increasingly common. We examined how mulch...

  13. Effects of Chemical Surface Treatment on Mechanical Properties of ...

    African Journals Online (AJOL)

    MBI

    2015-06-28

    Jun 28, 2015 ... ABSTRACT. Sisal fiber was extracted from Sisal leaves by enzymatic retting method. A portion of the fiber was subjected to alkali, benzoyl chloride and silane treatments. Sisal fiber composites were fabricated using unsaturated polyester resin, by hand lay-up technique using both the treated and untreated ...

  14. Economic study of the treatment of surface water by small ...

    African Journals Online (AJOL)

    The purpose of this work is to evaluate the possibility of utilising an ultrafiltration process for the treatment of water from the dam in the Kabylia region of Algeria and, in particular, for the provision of drinking water to people living in dispersed small villages. The water quality was determined by measuring turbidity, and ...

  15. Plasma surface treatment of Cu by nanosecond-pulse diffuse discharges in atmospheric air

    Science.gov (United States)

    Cheng, ZHANG; Jintao, QIU; Fei, KONG; Xingmin, HOU; Zhi, FANG; Yu, YIN; Tao, SHAO

    2018-01-01

    Nanosecond-pulse diffuse discharges could provide high-density plasma and high-energy electrons at atmospheric pressure. In this paper, the surface treatment of Cu by nanosecond-pulse diffuse discharges is conducted in atmospheric air. Factors influencing the water contact angle (WCA), chemical composition and microhardness, such as the gap spacing and treatment time, are investigated. The results show that after the plasma surface treatment, the WCA considerably decreases from 87° to 42.3°, and the surface energy increases from 20.46 mJ m-2 to 66.28 mJ m-2. Results of energy dispersive x-ray analysis show that the concentration of carbon decreases, but the concentrations of oxygen and nitrogen increase significantly. Moreover, the microhardness increases by approximately 30% after the plasma treatment. The aforementioned changes on the Cu surface indicate the plasma surface treatment enhances the hydrophilicity and microhardness, and it cleans the carbon and achieves oxidization on the Cu surface. Furthermore, by increasing the gap spacing and treatment time, better treatment effects can be obtained. The microhardness in the case of a 2.5 cm gap is higher than that in the case of a 3 cm gap. More oxygen and nitrogen species appear on the Cu surface for the 2.5 cm gap treatment than for the 3 cm gap treatment. The WCA significantly decreases with the treatment time when it is no longer than 90 s, and then it reaches saturation. In addition, more oxygen-containing and nitrogen-containing groups appear after extended plasma treatment time. They contribute to the improvement of the hydrophilicity and oxidation on the Cu surface.

  16. A Study of Atmospheric Plasma Treatment on Surface Energetics of Carbon Fibers

    International Nuclear Information System (INIS)

    Park, Soo Jin; Chang, Yong Hwan; Moon, Cheol Whan; Suh, Dong Hack; Im, Seung Soon; Kim, Yeong Cheol

    2010-01-01

    In this study, the atmospheric plasma treatment with He/O 2 was conducted to modify the surface chemistry of carbon fibers. The effects of plasma treatment parameters on the surface energetics of carbon fibers were experimentally investigated with respect to gas flow ratio, power intensity, and treatment time. Surface characteristics of the carbon fibers were determined by X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), Fourier transform infrared (FT-IR), Zeta-potential, and contact angle measurements. The results indicated that oxygen plasma treatment led to a large amount of reactive functional groups onto the fiber surface, and these groups can form together as physical intermolecular bonding to improve the surface wettability with a hydrophilic polymer matrix

  17. Microstructure evolution and tribological properties of acrylonitrile-butadiene rubber surface modified by atmospheric plasma treatment

    Science.gov (United States)

    Shen, Ming-xue; Zhang, Zhao-xiang; Peng, Xu-dong; Lin, Xiu-zhou

    2017-09-01

    For the purpose of prolonging the service life for rubber sealing elements, the frictional behavior of acrylonitrile-butadiene rubber (NBR) surface by dielectric barrier discharge plasma treatments was investigated in this paper. Surface microstructure and chemical composition were measured by atomic force microscopy, field-emission scanning electron microscopy, and X-ray photoelectron spectroscopy, respectively. Water contact angles of the modified rubber surface were also measured to evaluate the correlation between surface wettability and tribological properties. The results show that plasma treatments can improve the properties of the NBR against friction and wear effectively, the surface microstructure and roughness of plasma-modified NBR surface had an important influence on the surface tribological behavior, and the wear depth first decreased and then increased along with the change of plasma treatment time. It was found that the wettability of the modified surface was gradually improved, which was mainly due to the change of the chemical composition after the treatment. This study suggests that the plasma treatment could effectively improve the tribological properties of the NBR surface, and also provides information for developing wear-resistant NBR for industrial applications.

  18. Effects of air dielectric barrier discharge plasma treatment time on surface properties of PBO fiber

    International Nuclear Information System (INIS)

    Wang Qian; Chen Ping; Jia Caixia; Chen, Mingxin; Li Bin

    2011-01-01

    In this paper, the effects of air dielectric barrier discharge (DBD) plasma treatment time on surface properties of poly(p-phenylene benzobisoxazole) (PBO) fiber were investigated. The surface characteristics of PBO fiber before and after the plasma treatments were analyzed by dynamic contact angle (DCA) analysis, scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). DCA measurements indicated that the surface wettability of PBO fiber was improved significantly by increasing the fiber surface free energy via air DBD plasma treatments. The results were confirmed by the improvement of adhesion of a kind of thermoplastic resin to PBO fiber which was observed by SEM, showing that more resin was adhering evenly to the fiber surface. AFM measurement revealed that the surface topography of PBO fiber became more complicated and the surface roughness was greatly enhanced after the plasma treatments, and XPS analysis showed that some new polar groups (e.g. -O-C=O) were introduced on plasma treated PBO fiber surface. The results of this study also showed that the surface properties of PBO fiber changed with the elongation of plasma treatment time.

  19. Light transmittance and surface roughness of a feldspathic ceramic CAD-CAM material as a function of different surface treatments.

    Science.gov (United States)

    Ural, Çağrı; Duran, İbrahim; Evmek, Betül; Kavut, İdris; Cengiz, Seda; Yuzbasioglu, Emir

    2016-07-15

    The aim of the present study was to determine the effect of different surface treatments on light transmission of aesthetic feldspathic ceramics used in CAD-CAM chairside restorations. Forty eight feldspatic ceramic test specimens were prepared from prefabricated CAD-CAM blocks by using a slow speed diamond saw. Test specimens were prepared and divided into 4 groups (n = 12). In the control group, no surface treatments were applied on the feldspathic ceramic surfaces. In the hydrofluoric acid group, the bonding surfaces of feldspathic ceramics were etched with 9.5 % hydrofluoric acid. In the sandblasting group the feldspathic ceramic surfaces were air-abraded with 30-μm alumium oxide (Al2O3) particles and Er:YAG laser was used to irradiate the ceramic surfaces. The incident light power given by the LED device and the transmitted light power through each ceramic sample was registered using a digital LED radiometer device. Each polymerization light had a light guide with 8-mm-diameter tips. Light transmission of feldspathic ceramic samples was determined by placing it on the radiometer and irradiating the specimen for 10 s at the highest setting for each light polymerization. All specimens were coated with gold using a sputter coater and examined under a field emission scanning electron microscope. Surface roughness measurement each group were evaluated with 3D optical surface and tactile profilometers. One-way ANOVA test results revealed that both surface conditioning method significantly affect the light transmittance (F:412.437; p ceramic material below the value of 400 mW/cm(2) which is critical limit for safe polymerization.

  20. Influence of Surface Treatments on the Bond Strength of Resin Cements to Monolithic Zirconia.

    Science.gov (United States)

    Elsaka, Shaymaa E

    To assess the influence of surface treatment on the microtensile bond strength (μTBS) of resin cements to monolithic zirconia materials. Two types of monolithic zirconia (Zenostar T [ZT] and Prettau Anterior [PA]) were evaluated. The specimens were assigned to three groups based on the surface treatment applied: group 1: control, assintered; group 2: sandblasted with 50-μm Al₂O₃; group 3: tribochemically silica sandblasted. Two types of resin cements (Multilink Speed [MS] and Multilink N [MN]) were applied to each group for evaluating the bond strength using the μTBS test. The fractured specimens were observed with a stereomicroscope and SEM. Surface roughness and topography of monolithic zirconia were examined after treatment. Data were analyzed using ANOVA and Tukey's test. A Weibull analysis was performed on the bond strength data. The bond strength was significantly affected by the surface treatment and the type of resin cement (p zirconia (p = 0.387). Surface treatment with tribochemical silica sandblasting revealed significantly higher bond strength (p zirconia was changed due to surface treatments. The surface treatment of monolithic zirconia with tribochemical silica sandblasting enhanced the bond strength between zirconia and resin cements. Resins cements containing adhesive phosphate monomer (APM, MS) provided higher bond strength to monolithic zirconia than non-APM (MN).

  1. Surface treatment of aramid fiber by air dielectric barrier discharge plasma at atmospheric pressure

    International Nuclear Information System (INIS)

    Jia Caixia; Chen Ping; Liu Wei; Li Bin; Wang Qian

    2011-01-01

    Aramid fiber samples are treated by air dielectric barrier discharge (DBD) plasma at atmospheric pressure; the plasma treatment time is investigated as the major parameter. The effects of this treatment on the fiber surface physical and chemical properties are studied by using surface characterization techniques. Scanning electron microscopy (SEM) is performed to determine the surface morphology changes, X-ray photoelectron spectroscopy (XPS) is analyzed to reveal the surface chemical composition variations and dynamic contact angle analysis (DCAA) is used to examine the changes of the fiber surface wettability. In addition, the wetting behavior of a kind of thermoplastic resin, poly(phthalazinone ether sulfone ketone) (PPESK), on aramid fiber surface is also observed by SEM photos. The study shows that there seems to be an optimum treatment condition for surface modification of aramid fiber by the air DBD plasma. In this paper, after the 12 s, 27.6 W/cm 3 plasma treatment the aramid fiber surface roughness is significantly improved, some new oxygen-containing groups such as C-O, C=O and O=C-O are generated on the fiber surface and the fiber surface wettability is greatly enhanced, which results in the better wetting behavior of PPESK resin on the plasma-treated aramid fiber.

  2. Surface characterization and corrosion behavior of micro-arc oxidized Ti surface modified with hydrothermal treatment and chitosan coating

    International Nuclear Information System (INIS)

    Neupane, Madhav Prasad; Park, Il Song; Lee, Min Ho

    2014-01-01

    In the present work, we describe the surface modification of commercially pure titanium (CP-Ti) by a composite/multilayer coating approach for biomedical applications. CP-Ti samples were treated by micro-arc oxidation (MAO) and subsequently some of the samples were coated with chitosan (Chi) by dip coating method, while others were subjected to hydrothermal treatment (HT) followed by chitosan coating. The MAO, MAO/Chi, and MAO/HT/Chi coated Ti were characterized and their characteristics were compared with CP-Ti. X-ray diffraction and scanning electron microscopy were used to assess the structural and morphological characteristics. The average surface roughness was determined using a surface profilometer. The corrosion resistance of untreated and surface modified Ti in commercial saline at 298 K was evaluated by potentiodynamic polarization test. The results indicated that the chitosan coating is very well integrated with the MAO and MAO/HT coating by physically interlocking itself with the coated layer and almost sealed all the pores. The surface roughness of hydrothermally treated and chitosan coated MAO film was superior evidently to that with other sample groups. The corrosion studies demonstrated that the MAO, hydrothermally treated and chitosan coated sample enhanced the corrosion resistance of titanium. The result indicates that fabrication of hydrothermally treated MAO surface coatings with chitosan is a significant approach to protect the titanium from corrosion, hence enhancing the potential use of titanium as bio-implants. - Highlights: • Micro-arc oxidized (MAO) and hydrothermally treated (HT) Ti surfaces are coated with chitosan (Chi). • The MAO/HT/Chi surface exhibits pores sealing and enhanced the surface roughness. • The MAO/HT/Chi surface significantly increase the corrosion resistance. • The MAO/HT/Chi can be a potential surface of titanium for bio-implants

  3. Treatment of surfaces with low-energy electrons

    Czech Academy of Sciences Publication Activity Database

    Frank, Luděk; Mikmeková, Eliška; Lejeune, M.

    2017-01-01

    Roč. 407, JUN 15 (2017), s. 105-108 ISSN 0169-4332 R&D Projects: GA TA ČR(CZ) TE01020118; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : Low-energy electrons * Electron beam induced release * Graphene * Ultimate cleaning of surfaces Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Nano-processes (applications on nano-scale) Impact factor: 3.387, year: 2016

  4. Bioinspired Surface Treatments for Improved Decontamination: Silicon and Latex Polymer SLIPS Treatments

    Science.gov (United States)

    2017-06-27

    including measurement of sessile, sliding, and shedding contact angles , target spreading, and quantification of retention for the simulant compounds...METHODS Sessile contact angles for samples evaluated under this effort used three 3 µL droplets per surface with each droplet measured ...150°). Heptane wetted all surfaces, producing contact angles below the measurable threshold. Geometric surface energy was reduced by the SLIPS

  5. Improvement of Surface Properties of CP-Titanium by Thermo-Chemical Treatment (TCT) Process

    International Nuclear Information System (INIS)

    Jeong, Hyeon-Gyeong; Hur, Bo-Young; Lee, Dong-Geun; Lee, Yong-Tai; Yaskiv, O.

    2011-01-01

    The thermo-chemical treatment (TCT) process was applied to achieve surface hardening of CP titanium. The following three different surface modification conditions were tested so that the best surface hardening process could be selected:(a) PVD, (b) TCT+PVD, and (c) TCT+Aging+PVD. These specimens were tested and analyzed in terms of surface roughness, wear, friction coefficient, and the gradient of hardening from the surface of the matrix. The three test conditions were all beneficial to improve the surface hardness of CP titanium. Moreover, the TCT treated specimens, that is, (b) and (c), showed significantly improved surface hardness and low friction coefficients through the thickness up to 100um. This is due to the functionally gradient hardened surface improvement by the diffused interstitial elements. The hardened surface also showed improvement in bonding between the PVD and TCT surface, and this leads to improvement in wear resistance. However, TCT after aging treatment did not show much improvement in surface properties compared to TCT only. For the best surface hardening on CP titanium, TCT+PVD has advantages in surface durability and economics.

  6. [INVITED] Laser gas assisted treatment of Ti-alloy: Analysis of surface characteristics

    Science.gov (United States)

    Yilbas, B. S.; Ali, H.; Karatas, C.

    2016-04-01

    Laser gas assisted treatment of Ti6Al4V alloy surface is carried out and nitrogen/oxygen mixture with partial pressure of PO2/PN2=1/3 is introduced during the surface treatment process. Analytical tools are used to characterize the laser treated surfaces. The fracture toughness at the surface and the residual stress in the surface region of the laser treated layer are measured. Scratch tests are carried out to determine the friction coefficient of the treated surface. It is found that closely spaced regular laser scanning tracks generates a self-annealing effect in the laser treated layer while lowering the stress levels in the treated region. Introducing high pressure gas mixture impingement at the surface results in formation of oxide and nitride species including, TiO, TiO2, TiN and TiOxNy in the surface region. A dense layer consisting of fine size grains are formed in the surface region of the laser treated layer, which enhances the microhardness at the surface. The fracture toughness reduces after the laser treatment process because of the microhardness enhancement at the surface. The residual stress formed is comprehensive, which is in the order of -350 MPa.

  7. Fabrication of Nano-Micro Hybrid Structures by Replication and Surface Treatment of Nanowires

    Directory of Open Access Journals (Sweden)

    Yeonho Jeong

    2017-07-01

    Full Text Available Nanowire structures have attracted attention in various fields, since new characteristics could be acquired in minute regions. Especially, Anodic Aluminum Oxide (AAO is widely used in the fabrication of nanostructures, which has many nanosized pores and well-organized nano pattern. Using AAO as a template for replication, nanowires with a very high aspect ratio can be fabricated. Herein, we propose a facile method to fabricate a nano-micro hybrid structure using nanowires replicated from AAO, and surface treatment. A polymer resin was coated between Polyethylene terephthalate (PET and the AAO filter, roller pressed, and UV-cured. After the removal of aluminum by using NaOH solution, the nanowires aggregated to form a micropattern. The resulting structure was subjected to various surface treatments to investigate the surface behavior and wettability. As opposed to reported data, UV-ozone treatment can enhance surface hydrophobicity because the UV energy affects the nanowire surface, thus altering the shape of the aggregated nanowires. The hydrophobicity of the surface could be further improved by octadecyltrichlorosilane (OTS coating immediately after UV-ozone treatment. We thus demonstrated that the nano-micro hybrid structure could be formed in the middle of nanowire replication, and then, the shape and surface characteristics could be controlled by surface treatment.

  8. Laser surface treatment and the resultant hierarchical topography of Ti grade 2 for biomedical application

    Energy Technology Data Exchange (ETDEWEB)

    Kuczyńska, Donata, E-mail: donatakuczynska@gmail.com [Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw (Poland); Kwaśniak, Piotr [Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw (Poland); Marczak, Jan [Military University of Technology, Institute of Optoelectronics, Warsaw (Poland); Bonarski, Jan [Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Cracow (Poland); Smolik, Jerzy [Institute for Sustainable Technology–National Research Institute, Radom (Poland); Garbacz, Halina [Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw (Poland)

    2016-12-30

    Highlights: • Presented surface modification results in multimodal topography. • Laser treatment creates roughness in a range from nano- to micrometers. • Multimodal topography promote protein adsorption. • Hybrid surface treatment results in a texture favorable for osteogenic passes. - Abstract: Modern prosthesis often have a complex structure, where parts of an implant have different functional properties. This gradient of functional properties means that local surface modifications are required. Method presented in this study was develop to functionalize prefabricated elements with original roughness obtained by conventional treatments used to homogenize and clean surface of titanium implants. Demonstrated methodology results in multimodal, periodic grooved topography with roughness in a range from nano- to micrometers. The modified surfaces were characterized in terms of shape, roughness, wettability, surface energy and chemical composition. For this purpose, the following methods were used: scanning electron microscopy, optical profilometry, atomic force microscopy, contact angle measurements and X-ray photoelectron spectroscopy. Protein adsorption studies were conducted to determine the potential biomedical application of proposed method. In order to estimate the intensity and way of the protein adsorption process on different titanium surfaces, XPS studies and AFM measurements were performed. The systematic comparison of surface states and their osseointegration tendency will be useful to evaluate suitability of presented method as an single step treatment for local surface functionalization of currently produced implantable devices.

  9. Surface Treatment on Physical Properties and Biocompatibility of Orthodontic Power Chains

    Directory of Open Access Journals (Sweden)

    H. C. Cheng

    2017-01-01

    Full Text Available The conventional orthodontic power chain, often composed of polymer materials, has drawbacks such as a reduction of elasticity owing to water absorption as well as surface discoloration and staining resulting from food or beverages consumed by the patient. The goal of this study was to develop a surface treatment (nanoimprinting for orthodontic power chains and to alleviate their shortcomings. A concave template (anodic alumina was manufactured by anodization process using pure aluminum substrate by employing the nanoimprinting process. Convex nanopillars were fabricated on the surface of orthodontic power chains, resulting in surface treatment. Distinct parameters of the nanoimprinting process (e.g., imprinting temperature, imprinting pressure, imprinting time, and demolding temperature were used to fabricate nanopillars on the surface of orthodontic power chains. The results of this study showed that the contact angle of the power chains became larger after surface treatment. In addition, the power chains changed from hydrophilic to hydrophobic. The power chain before surface treatment without water absorption had a water absorption rate of approximately 4%, whereas a modified chain had a water absorption rate of approximately 2%–4%. Furthermore, the color adhesion of the orthodontic power chains after surface modification was less than that before surface modification.

  10. Surface Treatment on Physical Properties and Biocompatibility of Orthodontic Power Chains.

    Science.gov (United States)

    Cheng, H C; Chen, M S; Peng, B Y; Lin, W T; Shen, Y K; Wang, Y H

    2017-01-01

    The conventional orthodontic power chain, often composed of polymer materials, has drawbacks such as a reduction of elasticity owing to water absorption as well as surface discoloration and staining resulting from food or beverages consumed by the patient. The goal of this study was to develop a surface treatment (nanoimprinting) for orthodontic power chains and to alleviate their shortcomings. A concave template (anodic alumina) was manufactured by anodization process using pure aluminum substrate by employing the nanoimprinting process. Convex nanopillars were fabricated on the surface of orthodontic power chains, resulting in surface treatment. Distinct parameters of the nanoimprinting process (e.g., imprinting temperature, imprinting pressure, imprinting time, and demolding temperature) were used to fabricate nanopillars on the surface of orthodontic power chains. The results of this study showed that the contact angle of the power chains became larger after surface treatment. In addition, the power chains changed from hydrophilic to hydrophobic. The power chain before surface treatment without water absorption had a water absorption rate of approximately 4%, whereas a modified chain had a water absorption rate of approximately 2%-4%. Furthermore, the color adhesion of the orthodontic power chains after surface modification was less than that before surface modification.

  11. Hyperspectral Surface Analysis for Ripeness Estimation and Quick UV-C Surface Treatments for Preservation of Bananas

    Science.gov (United States)

    Zhao, W.; Yang, Zh.; Chen, Zh.; Liu, J.; Wang, W. Ch.; Zheng, W. Yu.

    2016-05-01

    This study aimed to determine the ripeness of bananas using hyperspectral surface analysis and how a rapid UV-C (ultraviolet-C light) surface treatment could reduce decay. The surface of the banana fruit and its stages of maturity were studied using a hyperspectral imaging technique in the visible and near infrared (370-1000 nm) regions. The vselected color ratios from these spectral images were used for classifying the whole banana into immature, ripe, half-ripe and overripe stages. By using a BP neural network, models based on the wavelengths were developed to predict quality attributes. The mean discrimination rate was 98.17%. The surface of the fresh bananas was treated with UV-C at dosages from 15-55 μW/cm2. The visual qualities with or without UV-C treatment were compared using the image, the chromatic aberration test, the firmness test and the area of black spot on the banana skin. The results showed that high dosages of UV-C damaged the banana skin, while low dosages were more efficient at delaying changes in the relative brightness of the skin. The maximum UV-C treatment dose for satisfactory banana preservation was between 21 and 24 μW/cm2. These results could help to improve the visual quality of bananas and to classify their ripeness more easily.

  12. Enhancement of Biocompatibility on Bioactive Titanium Surface by Low-Temperature Plasma Treatment

    Science.gov (United States)

    Lin, Chia-Cheng; Cheng, Hsin-Chung; Huang, Chiung-Fang; Lin, Che-Tong; Lee, Sheng-Yang; Chen, Chin-Sung; Ou, Keng-Liang

    2005-12-01

    The surface of implantable biomaterials directly contacts the host tissue and is critical in determining biocompatibility. To improve implant integration, interfacial reactions must be controlled to minimize nonspecific adsorption of proteins, and tissue-healing phenomena can be controlled. The purpose of this study was to develop a new method of functionalizing titanium surfaces by plasma treatment. The covalent immobilization of bioactive organic molecules and the bioactivities in vitro were assessed by transmission electron microscopy (TEM), atomic force spectroscopy (AFM), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay as indices of cellular cytotoxicity. Argon plasma removed all of the adsorbed contaminants and impurities. Plasma-cleaned titanium surfaces showed better bioactive performances than untreated titanium surfaces. The analytical results reveal that plasma-cleaned titanium surfaces provide a clean and reproducible starting condition for further plasma treatments to create well-controlled surface layers. Allylamine was ionized by plasma treatment, and acted as a medium to link albumin. Cells demonstrated a good spread, and a wide attachment was attained on the Albu-Ti plate. Cell attachment and growth were shown to be influenced by the surface properties. The plasma treatment process plays an important role in facilitating tissue healing. This process not only provides a clean titanium surface, but also leads to surface amination on plasma-treated titanium surfaces. Surface cleaning by ion bombardment and surface modification by plasma polymerization are believed to remove contamination on titanium surfaces and thus promote tissue healing.

  13. Oxygen Plasma Treatment of Rubber Surface by the Atmospheric Pressure Cold Plasma Torch

    DEFF Research Database (Denmark)

    Lee, Bong-ju; Kusano, Yukihiro; Kato, Nobuko

    1997-01-01

    adhesive. The adhesion property was improved by treatment of the rubber compound with plasma containing oxygen radicals. Physical and chemical changes of the rubber surface as a result of the plasma treatment were analyzed by field emission scanning electron microscopy (FE-SEM) and fourier transform......A new application of the atmospheric cold plasma torch has been investigated. Namely, the surface treatment of an air-exposed vulcanized rubber compound. The effect of plasma treatment was evaluated by the bondability of the treated rubber compound with another rubber compound using a polyurethane...

  14. Surfaces in classical geometries a treatment by moving frames

    CERN Document Server

    Jensen, Gary R; Nicolodi, Lorenzo

    2016-01-01

    Designed for intermediate graduate studies, this text will broaden students' core knowledge of differential geometry providing foundational material to relevant topics in classical differential geometry. The method of moving frames, a natural means for discovering and proving important results, provides the basis of treatment for topics discussed. Its application in many areas helps to connect the various geometries and to uncover many deep relationships, such as the Lawson correspondence. The nearly 300 problems and exercises range from simple applications to open problems. Exercises are embedded in the text as essential parts of the exposition. Problems are collected at the end of each chapter; solutions to select problems are given at the end of the book. Mathematica®, Matlab™, and Xfig are used to illustrate selected concepts and results. The careful selection of results serves to show the reader how to prove the most important theorems in the subject, which may become the foundation of future progress...

  15. Agro-Residues: Surface Treatment and Characterization of Date Palm Tree Fiber as Composite Reinforcement

    Directory of Open Access Journals (Sweden)

    Elsayed A. Elbadry

    2014-01-01

    Full Text Available The aims of this research are to investigate the effect of different surface treatment methods on the different properties of date palm fiber (DPF compared to raw DPF fibers such as surface morphology, density, thermal stability, and tensile properties. The first surface treatment is called surface hand cleaning which can be carried out by cleaning the fibers by soft sand cloth; the second one is the same as the first one after DPF heat treatment in the furnace at 100°C for 1.5 h and the third one is by chemical treatment with 1% NaOH at 100°C for 1 h. The results showed that the mechanical performance of DPF was enhanced by the different treatments and the chemical treatment has pronounced effect on the behavior of DPF. Raw fibers showed the highest variability and presented the lowest value of Weibull modulus, whereas the fibers showed less variability by carrying out the different treatments. Moreover, using soda treatment cleans the fiber surface which causes fibrillation and therefore the tensile strength of the fibers increases.

  16. Environmentally Benign Sol-Gel Surface Treatment for Aluminum Bonding Applications

    National Research Council Canada - National Science Library

    Osborne, Joseph

    1996-01-01

    A surface treatment process for aluminum using sol-gel chemistry has been developed that produces strong adhesive bonds without the rinse water requirements of traditional anodizing or etching processes...

  17. Corrosion resistance of hsla steel after various surface treatments in chloride environment

    Czech Academy of Sciences Publication Activity Database

    Borko, K.; Pastorek, F.; Fintová, Stanislava; Hadzima, B.

    2016-01-01

    Roč. 18, č. 4 (2016), s. 99-102 ISSN 1335-4205 Institutional support: RVO:68081723 Keywords : Corrosion properties * Iron phosphating * S355J steel Subject RIV: JK - Corrosion ; Surface Treatment of Materials

  18. Surface treatment of screw shaped titanium dental implants by high intensity laser pulses

    Science.gov (United States)

    Pető, G.; Karacs, A.; Pászti, Z.; Guczi, L.; Divinyi, T.; Joób, A.

    2002-01-01

    Machined and Al 2O 3 blasted surfaces of screw shaped Ti dental implants were irradiated by 30 ns pulses of Nd:glass laser at 1064 nm wavelength with 0.5-3 J pulse energy. The laser treatment increased the temperature of the Ti surface well above the melting temperature. The resulting ablation of some surface layers was followed by a very rapid solidification. These thermal processes strongly modified the original morphology of the surface and removed the contaminations. The new morphology was characterized by features mostly in ten micron and partly in submicron ranges. The surface composition was the same as the bulk titanium without any segregation. Animal experiments demonstrated that this surface treatment seems to be promising for the improvement of the osseointegration of dental implants.

  19. Influence of atmospheric pressure plasma treatment on surface properties of PBO fiber

    International Nuclear Information System (INIS)

    Zhang Ruiyun; Pan Xianlin; Jiang Muwen; Peng Shujing; Qiu Yiping

    2012-01-01

    Highlights: ► PBO fibers were treated with atmospheric pressure plasmas. ► When 1% of oxygen was added to the plasma, IFSS increased 130%. ► Increased moisture regain could enhance plasma treatment effect on improving IFSS with long treatment time. - Abstract: In order to improve the interfacial adhesion property between PBO fiber and epoxy, the surface modification effects of PBO fiber treated by atmospheric pressure plasma jet (APPJ) in different time, atmosphere and moisture regain (MR) were investigated. The fiber surface morphology, functional groups, surface wettability for control and plasma treated samples were analyzed by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and water contact angle measurements, respectively. Meanwhile, the fiber interfacial shear strength (IFSS), representing adhesion property in epoxy, was tested using micro-bond pull-out test, and single fiber tensile strength was also tested to evaluate the mechanical performance loss of fibers caused by plasma treatment. The results indicated that the fiber surface was etched during the plasma treatments, the fiber surface wettability and the IFSS between fiber and epoxy had much improvement due to the increasing of surface energy after plasma treatment, the contact angle decreased with the treatment time increasing, and the IFSS was improved by about 130%. The processing atmosphere could influence IFSS significantly, and moisture regains (MR) of fibers also played a positive role on improving IFSS but not so markedly. XPS analysis showed that the oxygen content on fiber surface increased after treatment, and C=O, O-C=O groups were introduced on fiber surface. On the other hand, the observed loss of fiber tensile strength caused by plasma treatment was not so remarkable to affect the overall performance of composite materials.

  20. The combined action of UV irradiation and chemical treatment on the titanium surface of dental implants

    Energy Technology Data Exchange (ETDEWEB)

    Spriano, Silvia [Politecnico di Torino, Department of Applied Science and Technology, Corso Duca degli Abruzzi, 24-10129 Torino (Italy); Ferraris, Sara, E-mail: sara.ferraris@polito.it [Politecnico di Torino, Department of Applied Science and Technology, Corso Duca degli Abruzzi, 24-10129 Torino (Italy); Bollati, Daniele; Morra, Marco; Cassinelli, Clara [Nobil Bio Ricerche, Portacomaro (Italy); Lorenzon, Giorgio [Centro Chirurgico, Via Mallonetto, 47, 10032, Brandizzo Torino (Italy)

    2015-09-15

    Highlights: • A combined UV irradiation and H{sub 2}O{sub 2} treatment was applied to titanium surfaces. • A thin, homogeneous, not porous, crack-free and bioactive oxide layer was obtained. • The process significantly improves the biological response of titanium surfaces. • A clinical case demonstrates the effectiveness of the proposed treatment. - Abstract: The purpose of this paper is to describe an innovative treatment for titanium dental implants, aimed at faster and more effective osteointegration. The treatment has been performed with the use of hydrogen peroxide, whose action was enhanced by concomitant exposure to a source of ultraviolet light. The developed surface oxide layer was characterized from the physical and chemical points of view. Moreover osteoblast-like SaOS2 cells were cultured on treated and control titanium surfaces and cell behavior investigated by scanning electron microscope observation and gene expression measurements. The described process produces, in only 6 min, a thin, homogeneous, not porous, free of cracks and bioactive (in vitro apatite precipitation) oxide layer. High cell density, peculiar morphology and overexpression of several genes involved with osteogenesis have been observed on modified surfaces. The proposed process significantly improves the biological response of titanium surfaces, and is an interesting solution for the improvement of bone integration of dental implants. A clinical application of the described surfaces, with a 5 years follow-up, is reported in the paper, as an example of the effectiveness of the proposed treatment.

  1. In vitro analysis of the influence of surface treatment of dental implants on primary stability

    Directory of Open Access Journals (Sweden)

    Carla Rodrigues Mazzo

    2012-08-01

    Full Text Available Surface treatment interferes with the primary stability of dental implants because it promotes a chemical and micromorphological change on the surface and thus stimulates osseointegration. This study aimed to evaluate the effects of different surface treatments on primary stability by analyzing insertion torque (IT and pullout force (PF. Eight samples of implants with different surface treatments (TS - external hexagon with acid surface treatment; and MS - external hexagon, machined surface, all 3.75 mm in diameter X 11.5 mm in length, were inserted into segments of artificial bones. The IT of each sample was measured by an electronic torquemeter, and then the pullout test was done with a universal testing machine. The results were subjected to ANOVA (p < 0.05, followed by Tukey's test (p < 0.05. The IT results showed no statistically significant difference, since the sizes of the implants used were very similar, and the bone used was not highly resistant. The PF values (N were, respectively, TS = 403.75 ± 189.80 and MS = 276.38 ± 110.05. The implants were shown to be different in terms of the variables of maximum force (F = 4.401, p = 0.0120, elasticity in maximum flexion (F = 3.672, p = 0.024, and relative stiffness (F = 4.60, p = 0.01. In this study, external hexagonal implants with acid surface treatment showed the highest values of pullout strength and better stability, which provide greater indication for their use.

  2. Antimicrobial and cold plasma treatments for inactivation of listeria monocytogenes on whole apple surface

    Science.gov (United States)

    Introduction: Produce and bacterial cell surface structure play an important role as to where and how bacteria attach to produce surfaces. The efficacy of a novel antimicrobial solution developed in our laboratory was investigated in combination with cold plasma treatments for inactivation of Liste...

  3. Color stability of a resin composite: Effect of the immersion method and surface treatments

    Directory of Open Access Journals (Sweden)

    L L Miotti

    2016-01-01

    Conclusions: Specimens totally immersed in staining solutions could in somehow overestimate the color change, once that in most clinical conditions not all of the restoration surfaces are exposed to the oral environment. Moreover, as the surface sealant application produces color change values that are clinically acceptable, it might be used in esthetic restorations as an adjunct treatment.

  4. Description of the surface water filtration and ozone treatment system at the Northeast Fishery Center

    Science.gov (United States)

    A water filtration and ozone disinfection system was installed at the U.S. Fish and Wildlife Service's Northeast Fishery Center in Lamar, Pennsylvania to treat a surface water supply that is used to culture sensitive and endangered fish. The treatment system first passes the surface water through dr...

  5. Improvement of Polytetrafluoroethylene Surface Energy by Repetitive Pulse Non-Thermal Plasma Treatment in Atmospheric Air

    International Nuclear Information System (INIS)

    Yang Guoqing; Zhang Guanjun; Zhang Wenyuan

    2011-01-01

    Improvement of polytetrafluoroethylene surface energy by non-thermal plasma treatment is presented, using a nanosecond-positive-edge repetitive pulsed dielectric barrier discharge generator in atmospheric air. The electrical parameters including discharging power, peak and density of micro-discharge current were calculated, and the electron energy was estimated. Surface treatment experiments of polytetrafluoroethylene films were conducted for both different applied voltages and different treating durations. Results show that the surface energy of polytetrafluoroethylene film could be improved to 40 mJ/m 2 or more by plasma treatment. Surface roughness measurement and surface X-ray photoelectron spectroscopy analysis indicate that there are chemical etching and implantation of polar oxygen groups in the sample surface treating process, resulting in the improvement of the sample surface energy. Compared with an AC source of 50 Hz, the dielectric barrier discharges generated by a repetitive pulsed source could provide higher peak power, lower mean power, larger micro-discharge current density and higher electron energy. Therefore, with the same applied peak voltage and treating duration, the improvement of polytetrafluoroethylene surface energy using repetitive pulsed plasma is more effective, and the plasma treatment process based on repetitive pulsed dielectric barrier discharges in air is thus feasible and applicable.

  6. Effect of surface treatments on the fatigue life of titanium for biomedical applications.

    Science.gov (United States)

    Pazos, L; Corengia, P; Svoboda, H

    2010-08-01

    Many surface treatments that are used in cementless and endosseous implants modify the topography and the roughness to increase the implant-bone contact area and thus favor bio-mechanical anchorage, shortening the period of osseointegration. Nevertheless, the effects that the surface treatments can have on the fatigue life of the material are not generally considered. In this sense, the superficial condition of the component is one of the features that affect the fatigue strength, specially the fatigue crack nucleation. The fatigue behaviour of annealed commercially pure titanium grade 4 was studied. The surface treatments used were acid etching, shot blasting and a dual treatment of blasting + acid etching. An as-machined surface condition was used as a reference. Topography, roughness, surface defects, microstructural changes and residual stresses were characterized in each case. Rotating-bending fatigue tests of each surface condition were conducted at room temperature with a frequency of 33 Hz. S-N curves and Basquin equations were obtained based on the results of these tests. Tested samples were also characterized to evaluate fatigue damage. The acid etching decreases the fatigue endurance, while the blasting and blasting + acid etching treatments showed a similar behaviour with respect to the reference condition. For acid etching, the modifications introduced (stress raisers) contributed to accelerate the nucleation of cracks. On the other hand, the treatments with a blasting stage besides generating stress raisers, introduced compressive residual stresses and superficial plastic deformation that tend to improve the fatigue endurance of the material.

  7. Surface modification of carbon nanohorns by helium plasma and ozone treatments

    Science.gov (United States)

    Lin, Zaw; Iijima, Toru; Selvam Karthik, Paneer; Yoshida, Mitsunobu; Hada, Masaki; Nishikawa, Takeshi; Hayashi, Yasuhiko

    2017-01-01

    In this paper, we describe the effects of helium plasma and ozone treatments on the dispersibility of carbon nanohorns (CNHs) in water. The experimental setups have been designed to efficiently generate helium plasma and ozone by dielectric barrier discharge at atmospheric pressure. After being treated with ozone, the oxygen-containing functional groups were introduced to the surface of CNHs, and are responsible for better dispersion. Helium plasma treatment was performed separately and it resulted in hydroxyl functional groups on the surface of CNHs. It was also found that the sizes of CNHs in water were smaller after ozone treatment. However, plasma-treated CNHs were bigger than ozone treated CNHs. The dispersed CNHs modified by ozone treatment were stable for more than three months without precipitation. In contrast, though helium plasma treatment introduced hydroxyl groups to the surface of CNHs, the dispersibility decreased and the flocculation of CNHs was observed in a few minutes.

  8. Impact of Surface Treatment on the Structural and Electronic Properties of Polished CdZnTe Surfaces for Radiation Detectors

    Science.gov (United States)

    Tari, Suleyman; Aqariden, F.; Chang, Y.; Grein, C.; Li, Jin; Kioussis, N.

    2013-11-01

    We present the effects of surface treatments on the structural and electronic properties of chemomechanically polished Cd0.9Zn0.1Te before contact deposition. Specifically, polished CdZnTe (CZT) samples were treated with four distinct chemical etchants: (1) bromine methanol (BM), (2) bromine in lactic acid, (3) bromine in methanol followed by bromine-20% lactic acid in ethylene glycol, and (4) hydrochloric acid (HCl). The surface structure and surface electronic properties were studied with atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS). AFM images showed that three of the four etchants significantly altered the surface morphology and structure of CZT. All etchants created smoother surfaces; however, all except HCl also introduced high densities of defects. HCl was found to not affect the surface structure. XPS measurements indicated that a thick, ˜3 nm to 4 nm, TeO2 layer formed about 1 h after etching; hence, it is very important to process devices immediately after etching to prevent oxide formation.

  9. Bituminization of simulated waste, spent resins, evaporator concentrates and animal ashes by extrusion process

    International Nuclear Information System (INIS)

    Grosche Filho, C.E.; Chandra, U.

    1987-01-01

    The results of the study of bituminization of simulated radwaste - spennt ion-exchange resins, borate evaporator/concentrates and animal ashes, are presented and discussed. Distilled and oxidizer bitumen were used. Characterization of the crude material and simulated wastes-bitumen mixtures of varying weigt composition (30, 40, 50, 60% by weight of dry waste material) was carried out. The asphaltene and parafin contents in the bitumens were also determined. Some additives and were used with an aim to improve the characteristcs of solidified wastes. For leaching studies, granular ion-exchange resins were with Cs - 134 and mixtures of resin-bitumen were prepared. The leaching studies were executed using the IAEA recommendation and the ISO method. A conventional screw-extruder, common in plastic industry, was used determine operational parameters and process difficulties. Mixtures of resin-bitumen and evaporator concentrate-bitumen obtained from differents operational conditions were characterized. (Author) [pt

  10. Influence of Antioxidant-Enhanced Polymers in Bitumen Rheology and Bituminous Concrete Mixtures Mechanical Performance

    Directory of Open Access Journals (Sweden)

    Samer Dessouky

    2015-01-01

    Full Text Available This paper evaluates the effect of polymer enhancement with antioxidant in the rheological properties of bitumen and mechanical properties of bituminous concrete mixture (BCM. In this study, two antioxidant-enhanced polymers were utilized in mitigating bitumen hardening due to aging. The rheological testing consists of temperature sweep using Dynamic Shear Rheometer at various aging conditions. Critical stiffness temperature data from the sweep test suggested that enhanced polymer exhibits less long-term hardening and brittleness compared to standard polymer. The mechanical testing consists of dynamic modulus, indirect tensile, flow number, and beam fatigue tests on BCM exposed to short-term aging. Hamburg wheel tracking test was also performed to assess moisture-damage susceptibility. It is found that the enhanced-polymer BCM exhibited higher modulus, higher tensile strength ratio, improved rutting resistance, lower moisture-damage susceptibility, and slightly increased fatigue life as compared to standard-polymer BCM.

  11. Study of Rheological Properties of Bituminous Binders in Middle and High Temperatures

    Directory of Open Access Journals (Sweden)

    Remišová Eva

    2016-05-01

    Full Text Available The bitumen binders in road pavements are exposed traffic loading effect at different climatic conditions. A resistance to these stresses depends on bitumen properties as well. The paper presents rheological properties (G*, δ, ν* determined and compared for four bituminous binders (unmodified and polymer modified bitumen at temperature 46 – 60 (80 °C and dynamic viscosity at temperature 130 – 190 °C (Brookfield viscometer. On the basis of viscosity results it is possible to set optimal production and compaction temperatures. Elastic and viscous behavior of binder in the middle temperature is determined in rheometers. The higher value of complex modulus, the stiffer bitumen binder is able to resist deformation. The greater content of elastic components (e.g. polymer in bitumen varies mainly elastic-viscous properties of primary bitumen.

  12. Development of advanced air-blown entrained-flow two-stage bituminous coal IGCC gasifier

    Directory of Open Access Journals (Sweden)

    Abaimov Nikolay A.

    2017-01-01

    Full Text Available Integrated gasification combined cycle (IGCC technology has two main advantages: high efficiency, and low levels of harmful emissions. Key element of IGCC is gasifier, which converts solid fuel into a combustible synthesis gas. One of the most promising gasifiers is air-blown entrained-flow two-stage bituminous coal gasifier developed by Mitsubishi Heavy Industries (MHI. The most obvious way to develop advanced gasifier is improvement of commercial-scale 1700 t/d MHI gasifier using the computational fluid dynamics (CFD method. Modernization of commercial-scale 1700 t/d MHI gasifier is made by changing the regime parameters in order to improve its cold gas efficiency (CGE and environmental performance, namely H2/CO ratio. The first change is supply of high temperature (900°C steam in gasifier second stage. And the second change is additional heating of blast air to 900°C.

  13. Development of advanced air-blown entrained-flow two-stage bituminous coal IGCC gasifier

    Science.gov (United States)

    Abaimov, Nikolay A.; Ryzhkov, Alexander F.

    2017-10-01

    Integrated gasification combined cycle (IGCC) technology has two main advantages: high efficiency, and low levels of harmful emissions. Key element of IGCC is gasifier, which converts solid fuel into a combustible synthesis gas. One of the most promising gasifiers is air-blown entrained-flow two-stage bituminous coal gasifier developed by Mitsubishi Heavy Industries (MHI). The most obvious way to develop advanced gasifier is improvement of commercial-scale 1700 t/d MHI gasifier using the computational fluid dynamics (CFD) method. Modernization of commercial-scale 1700 t/d MHI gasifier is made by changing the regime parameters in order to improve its cold gas efficiency (CGE) and environmental performance, namely H2/CO ratio. The first change is supply of high temperature (900°C) steam in gasifier second stage. And the second change is additional heating of blast air to 900°C.

  14. Fixed-bed gasification research using US coals. Volume 9. Gasification of Elkhorn bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Thimsen, D.; Maurer, R.E.; Pooler, A.R.; Pui, D.; Liu, B.; Kittelson, D.

    1985-05-01

    A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) group. This report is the ninth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of Elkhorn bituminous coal. The period of gasificastion test was September 13 to October 12, 1983. 9 refs., 24 figs., 35 tabs.

  15. Application of laser microprobe (LAMMA 1000) to "fingerprinting" of coal constituents in bituminous coal

    Science.gov (United States)

    Lyons, P.C.; Hercules, D.M.; Morelli, J.J.; Sellers, G.A.; Mattern, D.; Thompson-Rizer, C. L.; Brown, F.W.; Millay, M.A.

    1987-01-01

    A laser microprobe (LAMMA-1000) microchemical analysis of vitrinites of different morphologies but similar reflectances within the same bituminous coal bed indicates distinct "fingerprint" spectra. The banded form of vitrinite contains Li, Ti, Ba, Sr, F, and Cl which were not detected in the nonbanded vitrinite. These differences may indicate a different plant source or the introduction of these elements from fluids mobilized during diagenesis. The nonbanded vitrinite (called corpocollinite), which was contained in a pyrite coal-ball seed fern permineralization of Myeloxylon, may have been protected from influx of these elements due to entrapment by pyrite during an early peat stage. An ion at M/Z 65, which is characteristic of the banded vitrinite, may indicate C5H5+ and, perhaps a difference in the chemical structure of the two vitrinites. These results demonstrate that "fingerprint" spectra can be obtained from vitrinite macerals by LAMMA and that these "fingerprints" have genetic implications. ?? 1987.

  16. Distribution of inorganic and organic substances in the hydrocyclone separated Slovak sub-bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Anton Zubrik; Slavomir Hredzak; Ludmila Turcaniova; Michal Lovas; Ingo Bergmann; Klaus Dieter Becker; Maria Lukcova; Vladimir Sepelak [Slovak Academy of Sciences, Kosice (Slovakia). Institute of Geotechnics

    2010-08-15

    A low-rank Slovak sub-bituminous coal from the Handlova deposit was physically treated by washing in a water-only cyclone with the goal to find the separation effect for inorganic (mainly Fe-bearing minerals) and organic substances (humic acids, diterpanes). A high-quality coal product with the ash content in the dry matter of 9.02% and carbon content of C{sup d} = 68.12% at a mass yield of 29.51% was obtained using the water-only cyclone processing. At first, the physically treated coal samples were detailed characterized by XRD, {sup 57}Fe Moessbauer spectroscopy, FT-IR and HR-TEM. In addition to non-crystalline organic coal components, inorganic compounds belonging to silicate minerals (kaolinite, muscovite and quartz) as well as to Fe-bearing sulphide minerals (pyrite) were identified in the sub-bituminous coal by XRD. {sup 57}Fe Moessbauer spectroscopy detected the presence of iron carbonate (siderite), iron-containing clay mineral and two sulphur-containing minerals (pyrite, jarosite) in the untreated coal. On the other hand, only one Fe-bearing mineral, (pyrite) was found in the washed coal. Effect of the physical separation is also demonstrated in FT-IR spectra, where the peak at 1040 cm{sup -1} representing the silicate component in the untreated sample is not detectable in the washed coal sample. Presence of extractive organic substances, i.e. humic acids and tetracyclic diterpane (16a(H)-phyllocladane), in the hydrocyclone products is also evidenced. It was confirmed that the isolated diterpenoic compound is attendant in the washed product with the lowest ash content and it is assimilated with the organic part of coal. Surprisingly, humic acids were found in the highest concentration in the slurry that has the highest content of ash (63.14%). 54 refs., 8 figs., 5 tabs.

  17. Using proximate analysis to characterize airborne dust generation from bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Page, S.J.; Organiscak, J.A. [NIOSH, Pittsburgh, PA (United States). Pittsburgh Research Lab.

    2002-06-01

    Laboratory crushing experiments were conducted on a range of low to high volatile bituminous coals to investigate the various factors influencing airborne respirable dust generation. Bituminous coal samples from 8 mines (5 U.S. and 3 Polish) were uniformly prepared and processed through a double roll crusher located in a low air velocity wind tunnel. Experimental factors studied included inherent coal seam constituents, specific energy of crushing, product size characteristics, dust cloud electrostatic field, and specific quantity of airborne respirable dust generated. A combination of factors is associated with the generation of airborne respirable dust. One factor involved is the effect of coal rank, described by the inherent moist fuel ratio, on the product size characteristics. However, since coals of high moist fuel ratio (high rank) are generally more extensively cleated, it is suggested that the degree of cleating is directly responsible for the quantity of respirable-sized particles produced in the crushed product material for eastern U.S. coals. This is implied by the relationship of ash content and at least one mineral constituent (pyrite, determined from pyritic sulfur analysis) to the percentage of airborne respirable dust. A clear delineation of coals, based on well-known proximate analysis characteristics, that generate the most respirable dust appears to be possible. It was also shown that the dust-generating characteristics of coals could be reasonably described by both the moist fuel ratio and the Hardgrove Grindability Index (HGI). These results show a clear distinction between eastern and western U.S. coals. However, no consistent distinction for Polish coal was observed.

  18. HARDENING OF CRANE RAILS BY PLASMA DISCRETE-TIME SURFACE TREATMENT

    Directory of Open Access Journals (Sweden)

    S. S. Samotugin

    2017-01-01

    Full Text Available Crane wheels and rails are subjected to intensive wear in the process of operation. Therefore, improvement of these components’ performance can be considered a task of high importance. A promising direction in this regard is surface treatment by highly concentrated energy flows such as laser beams or plasma jets. This thesis suggests that the use of gradient plasma surface treatment can improve the performance of crane rails. A research was conducted, according to which hardened zones were deposited on crane rails under different treatment modes. Microhardness was measured both at the surface and in depth using custom-made microsections. The article includes the results of study of plasma surface hardening effects on wear resistance of crane rails. Change of plasma surface treatment parameters (current, plasma torch movement speed, argon gas flow rate allows for desired steel hardness and structure, while the choice of optimal location for hardened zones makes it possible to significantly improve wear resistance and crack resistance. As a result of plasma surface hardening, the fine-grained martensite structure is obtained with mainly lamellar morphology and higher hardness rate compared toinduction hardening or overlaying. Wear test of carbon steels revealed that plasma surfacing reduces abrasive wear rate compared to the irinitial state by 2 to 3 times. Enough sharp boundary between hardened and non-hardened portions has a positive effect on the performance of parts under dynamic loads, contributing to the inhibition of cracks during the transition from solid to a soft metal. For carbon and low alloy rail steels, the properties achieved by plasma surface hardening can effectively replace induction hardening or overlaying.The mode range for plasma surface treatment that allow sobtaining a surface layer with certain operating properties has been determined.

  19. Influence of surface treatments on the surface properties of different zirconia cores and adhesion of zirconia-veneering ceramic systems.

    Science.gov (United States)

    Elsaka, Shaymaa E

    2013-10-01

    The aim of this study was to assess the influence of surface treatments on the surface characteristics of different zirconia cores and the adhesion of the zirconia-veneering ceramic systems by means of strain energy release rate (G-value, J/m(2)). Three types of zirconia cores (NANOZR (NZ), Vita In-Ceram YZ (VZ), and IPS e.max ZirCAD (IZ)) were used. The specimens were divided into four groups in each test according to the surface treatment used; Gr 1 (control; no treatment), Gr 2 (sandblasted), Gr 3 (CH2Cl2 for 60min), and Gr 4 (experimental hot etching solution for 60min). AFM, SEM, EDS, and XRD were carried out. Two types of veneering ceramics (Vita VM9 (V9) and IPS e.max Ceram (IC)) were used for testing the adhesion. The G-value (J/m(2)) was measured with a four-point bending configuration. Following fracture testing specimens were examined with SEM. Data were analyzed using ANOVA and Tukey's test. NZ treated with the experimental hot etching solution showed the highest Ra values (206.06±9.98nm) compared with the other groups (Pveneering ceramic systems. The experimental hot etching solution could be considered as alternative treatment modality to sandblasting for zirconia cores to avoid phase transition at the surface from tetragonal to monoclinic that may be detrimental for the longevity of the zirconia-veneering ceramic restoration. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  20. Hard Surface Layers by Pack Boriding and Gaseous Thermo-Reactive Deposition and Diffusion Treatments

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Bottoli, Federico; Dahl, Kristian Vinter

    2017-01-01

    subjected to TRD (chromizing and titanizing) and boriding treatments. For the steels with low carbon content, chromizing results in surface alloying with chromium, i.e., formation of a (soft) “stainless” surface zone. Steels containing higher levels of carbon form chromium carbide (viz. Cr23C6, Cr7C3......) layers with hardnesses up to 1800 HV. Titanizing of ARNE tool steel results in a surface layer consisting of TiC with a hardness of approximately 4000 HV. Duplex treatments, where boriding is combined with subsequent (TRD) titanizing, result in formation of hard TiB2 on top of a thick layer of Fe...

  1. A Review of the Various Surface Treatments of NiTi Instruments.

    Science.gov (United States)

    Mohammadi, Zahed; Soltani, Mohammad Karim; Shalavi, Sousan; Asgary, Saeed

    2014-01-01

    Since the introduction of engine-driven nickel-titanium (NiTi) instruments, attempts have been made to minimize or eliminate their inherent defects, increase their surface hardness/flexibility and also improve their resistance to cyclic fatigue and cutting efficiency. The various strategies of enhancing instrument surface include ion implantation, thermal nitridation, cryogenic treatment and electropolishing. The purpose of this paper was to review the metallurgy and crystal characteristics of NiTi alloy and to present a general over review of the published articles on surface treatment of NiTi endodontic instruments.

  2. Surface modification of polylactic acid films by atmospheric pressure plasma treatment

    Science.gov (United States)

    Kudryavtseva, V. L.; Zhuravlev, M. V.; Tverdokhlebov, S. I.

    2017-09-01

    A new approach for the modification of polylactic acid (PLA) materials using atmospheric pressure plasma (APP) is described. PLA films plasma exposure time was 20, 60, 120 s. The surface morphology and wettability of the obtained PLA films were investigated by atomic force microscopy (AFM) and the sitting drop method. The atmospheric pressure plasma increased the roughness and surface energy of PLA film. The wettability of PLA has been improved with the application of an atmospheric plasma surface treatment. It was shown that it is possible to obtain PLA films with various surface relief and tunable wettability. Additionally, we demonstrated that the use of cold atmospheric pressure plasma for surface activation allows for the immobilization of bioactive compounds like hyaluronic acid (HA) on the surface of obtained films. It was shown that composite PLA-HA films have an increased long-term hydrophilicity of the films surface.

  3. Oxygen Plasma Treatment of Rubber Surface by the Atmospheric Pressure Cold Plasma Torch

    DEFF Research Database (Denmark)

    Lee, Bong-ju; Kusano, Yukihiro; Kato, Nobuko

    1997-01-01

    A new application of the atmospheric cold plasma torch has been investigated. Namely, the surface treatment of an air-exposed vulcanized rubber compound. The effect of plasma treatment was evaluated by the bondability of the treated rubber compound with another rubber compound using a polyurethane...

  4. Advantage Clean & Porous TM new technological methods of surface treatment of dental implants

    Directory of Open Access Journals (Sweden)

    Лев Ильич Винников

    2015-02-01

    Full Text Available The purpose of this study was a comparative analysis of the surfaces of dental implants treated with technological methods SLA and RBM to identify their positive and negative characteristics. Based on these results to develop a new process Clean & Porous surface treatment of dental implants to obtain highly, rough and porous surface, which is characteristic for the technology SLA, and absolutely clean surface characteristic of technology RBM, without their disadvantages (unwarranted complete removal of abrasive particles SLA case and the absence of a clear structure of the surface topography in the case of RBM.The structure and purity of the implant surface Straumann, Alfa-Bio, DIO, Finish Line. studied in micrographs obtained by an electron microscope (SEM at the University of Technion (increase 500,2000,3000. To study the chemical properties of the samples, the method of X-ray energy dispersive spectroscopy (EDS, based on an analysis of its X-ray emission energy spectrum.Comparative analysis of the implant surfaces treated with the methods and RBM SLA showed that despite the reliability of these methods, each of them has certain disadvantages (contamination cases alumina particle surface with sufficient structural SLA and craters on the surface organized RBM. Developed by Finish Line Materials and Processes Ltd new technology of surface treatment of dental implants Clean & PorousTM, combining the best characteristics of the methods of SLA and RBM, possible to obtain a well-structured and absolutely clean surface.The proposed new original method Clean & PorousTM treatment of dental implants meet the criteria (roughness, porosity and surface finish of the implant, which provide an ideal osseointegration. Since osseointegration is a key issue in modern implantology it enables to obtain reliable primary fixation of the implant in the bone. From a clinical point of view it reduces the healing of the implant, as well as creating conditions

  5. Treatment by gliding arc of epoxy resin: preliminary analysis of surface modifications

    Science.gov (United States)

    Faubert, F.; Wartel, M.; Pellerin, N.; Pellerin, S.; Cochet, V.; Regnier, E.; Hnatiuc, B.

    2016-12-01

    Treatments with atmospheric pressure non-thermal plasma are easy to implement and inexpensive. Among them gliding arc (GlidArc) remains rarely used in surface treatment of polymers. However, it offers economic and flexible way to treat quickly large areas. In addition the choice of carrier gas makes it possible to bring the active species and other radicals allowing different types of grafting and functionalization of the treated surfaces, for example in order to apply for anti-biofouling prevention. This preliminary work includes analysis of the surface of epoxy resins by infrared spectroscopy: the different affected chemical bonds were studied depending on the duration of treatment. The degree of oxidation (the C/O ratio) is obtained by X-ray microanalysis and contact angle analysis have been performed to determinate the wettability properties of the treated surface. A spectroscopic study of the plasma allows to determine the possible active species in the different zones of the discharge.

  6. Surface treatment systems for concrete in marine environment: Effect of concrete cover thickness

    Directory of Open Access Journals (Sweden)

    Marcelo Henrique Farias de Medeiros

    Full Text Available Abstract There are some ways to extend the service life of a reinforced concrete structure. This paper focuses on the extension of the service life by treating the surface of reinforced concrete, specifically on the effect of the concrete cover thickness on the surface treatment system efficacy. Thus, chloride migration tests were performed and diffusion chloride coefficients were calculated. The service life of each case (treated or non-treated concrete was estimated using these data and Fick's second law of diffusion. Results indicated that the thicker the concrete cover is, the greater the efficacy of the concrete surface treatment system will be. The dissemination of this information is important, since it is almost intuitive to think that the effect of a surface treatment system depends only on itself and this study shows the opposite.

  7. Influence of surface treatment on bond strength of veneering ceramics fused to zirconia.

    Science.gov (United States)

    Tada, Kouki; Sato, Toru; Yoshinari, Masao

    2012-01-01

    In all-ceramic restorations involving a zirconia framework, surface treatment of the zirconia surface is required to enhance bonding strength with the veneering ceramics and thus prevent chipping. The purpose of the present study was to investigate the influence of surface roughness and heat treatment of the zirconia and use of liner porcelain on bond strength between veneering ceramics and a zirconia framework. Debonding/crack-initiation strength (τb) was determined according to ISO 9693. No significant difference was observed among conditions, except with use of a liner under heat treatment, which yielded a τb of 26.0±2.9-28.9±1.7 MPa. Electron probe microanalysis revealed that components of the veneering ceramics remained on the zirconia surface after debonding, suggesting that fractures occur in the veneering ceramics and that improving the strength of the veneering ceramics themselves might increase bond strength.

  8. The effect of different surface treatments on the molten salt hot corrosion of IN-657 superalloy

    International Nuclear Information System (INIS)

    Otero, E.; Utrilla, M.V.

    1996-01-01

    The influence of different surface treatments (laser surface treatment, silicon nitride, and 25 wt.% Al 2 (OH) 4 Si 2 O 5 -75 wt.% Na 2 SiO 3 ), on the hot corrosion behaviour of IN-657 superalloy has been studied. The corrosion tests were performed in an oxidizing atmosphere in contact with a molten mixture of 82% K 2 S 2 O 7 -18% V 2 O 5 . The effects of operation temperature and carbon residues as component of the molten mixture were also analyzed. The best results were obtained for the kaolin and methasilicate mixture coating. Laser surface treatment and the CVD-silicon nitride are not recommended for surface modification of the IN-657 superalloy. Taking into account the results obtained, the authors suggest the average temperature and molten salt compositions where the above coating can work satisfactorily. (orig.)

  9. Influence of Heat Treatment on Mercury Cavitation Resistance of Surface Hardened 316LN Stainless Steel

    Energy Technology Data Exchange (ETDEWEB)

    Pawel, Steven J [ORNL; Hsu, Julia [Massachusetts Institute of Technology (MIT)

    2010-11-01

    The cavitation-erosion resistance of carburized 316LN stainless steel was significantly degraded but not destroyed by heat treatment in the temperature range 500-800 C. The heat treatments caused rejection of some carbon from the carburized layer into an amorphous film that formed on each specimen surface. Further, the heat treatments encouraged carbide precipitation and reduced hardness within the carburized layer, but the overall change did not reduce surface hardness fully to the level of untreated material. Heat treatments as short as 10 min at 650 C substantially reduced cavitation-erosion resistance in mercury, while heat treatments at 500 and 800 C were found to be somewhat less detrimental. Overall, the results suggest that modest thermal excursions perhaps the result of a weld made at some distance to the carburized material or a brief stress relief treatment will not render the hardened layer completely ineffective but should be avoided to the greatest extent possible.

  10. Electrical Characteristics of Carbon Nanotubes by Plasma and Microwave Surface Treatments

    International Nuclear Information System (INIS)

    Cho, Sangjin; Lee, Soonbo; Boo, Jinhyo; Shrestha, Shankar Prasad

    2014-01-01

    The plasma and microwave surface treatments of carbon nanotubes that loaded on plastic substrates were carried out with expecting a change of carbon nanotube dispersion by increasing treatment time. The microwave treatment process was undergone by commercial microwave oven (800 W). The electrical property was measured by hall measurement and resistance was increased by increasing O 2 flow rate of plasma, suggesting an improvement of carbon nanotube dispersion and a possibility of controlling the resistances of carbon nanotubes by plasma surface treatment. The resistance was increased in both polyethylene terephthalate and polyimide substrates by increasing O 2 flow rate. Resistance changes only slightly with different O 2 flow treatment in measure rho for all polyimide samples. Sheet resistance is lowest in polyimide substrate not due to high carbon nanotube loading but due to tendency to remain in elongated structure. O 2 or N 2 plasma treatments on both polyethylene terephthalate and polyimide substrates lead to increase in sheet resistance

  11. Investigation the effects of metallic substrate surfaces due to ion-plasma treatment

    International Nuclear Information System (INIS)

    Shulaev, V.M.; Taran, V.S.; Timoshenko, A.I.; Gasilin, V.V.

    2011-01-01

    It has been found correlation between modification effects and duration of ion-plasma cleaning the substrate surface with titanium ions. Experiments were carried out using serial vacuum-arc equipment ''Bulat-6'' at the stationary mode in non-filtered titanium plasma, which contained considerable quantity of evaporated material droplets. The polished cylinder substrates (diameter and height 9,14,20 mm) have been treated. The substrates were manufactured of stainless steel 12X18H10T and non-oxygen copper M00b. The substrates surface roughness after ion-plasma treatment has been investigated with electron microscope JEOL JSM-840 and optic interference non-contact profilograph- profilometer ''Micron-alpha''. According obtained results the surface of copper and stainless steel substrates has been treated to intensive modification, i.e. substrate surface after treatment significantly differs from initial one. During final ion-plasma treatment a number of effects occur: purification from surface oxides is accompanied with metallic surface ''contamination'' by the cathode material macrodroplets, surface micromelting accompanied by roughness increase, the surface layer annealing with noticeable decrease of hardness.

  12. Bond strength of resin-resin interfaces contaminated with saliva and submitted to different surface treatments.

    Science.gov (United States)

    Furuse, Adilson Yoshio; da Cunha, Leonardo Fernandes; Benetti, Ana Raquel; Mondelli, José

    2007-12-01

    The purpose of this study was to investigate the effect of different surface treatments on shear bond strength of saliva-contaminated resin-resin interfaces. Flat resin surfaces were fabricated. In the control group, no contamination or surface treatment was performed. The resin surfaces of the experimental groups were contaminated with saliva and air-dried, and then submitted to: (G1) rinsing with water and drying; (G2) application of an adhesive system; (G3) rinsing and drying, abrasion with finishing disks, etching and application of adhesive system; (G4) rinsing and drying, etching, application of silane and adhesive system. Resin cylinders were placed over the treated surfaces. The specimens were stored in water or ethanol. Shear bond strength tests were performed and the mode of failure was evaluated. Data were submitted to two-way ANOVA and Dunnett T3 test. Contamination of resin-resin interfaces with saliva significantly reduced shear strength, especially after prolonged storage (presin increments.

  13. Surface Texture-Based Surface Treatments on Ti6Al4V Titanium Alloys for Tribological and Biological Applications: A Mini Review

    Directory of Open Access Journals (Sweden)

    Naiming Lin

    2018-03-01

    Full Text Available Surface texture (ST has been confirmed as an effective and economical surface treatment technique that can be applied to a great range of materials and presents growing interests in various engineering fields. Ti6Al4V which is the most frequently and successfully used titanium alloy has long been restricted in tribological-related operations due to the shortcomings of low surface hardness, high friction coefficient, and poor abrasive wear resistance. Ti6Al4V has benefited from surface texture-based surface treatments over the last decade. This review begins with a brief introduction, analysis approaches, and processing methods of surface texture. The specific applications of the surface texture-based surface treatments for improving surface performance of Ti6Al4V are thoroughly reviewed from the point of view of tribology and biology.

  14. Surface Texture-Based Surface Treatments on Ti6Al4V Titanium Alloys for Tribological and Biological Applications: A Mini Review.

    Science.gov (United States)

    Lin, Naiming; Li, Dali; Zou, Jiaojuan; Xie, Ruizhen; Wang, Zhihua; Tang, Bin

    2018-03-24

    Surface texture (ST) has been confirmed as an effective and economical surface treatment technique that can be applied to a great range of materials and presents growing interests in various engineering fields. Ti6Al4V which is the most frequently and successfully used titanium alloy has long been restricted in tribological-related operations due to the shortcomings of low surface hardness, high friction coefficient, and poor abrasive wear resistance. Ti6Al4V has benefited from surface texture-based surface treatments over the last decade. This review begins with a brief introduction, analysis approaches, and processing methods of surface texture. The specific applications of the surface texture-based surface treatments for improving surface performance of Ti6Al4V are thoroughly reviewed from the point of view of tribology and biology.

  15. Shear bond strength of veneering ceramic to coping materials with different pre-surface treatments.

    Science.gov (United States)

    Tarib, Natasya Ahmad; Anuar, Norsamihah; Ahmad, Marlynda

    2016-10-01

    Pre-surface treatments of coping materials have been recommended to enhance the bonding to the veneering ceramic. Little is known on the effect on shear bond strength, particularly with new coping material. The aim of this study was to investigate the shear bond strength of veneering ceramic to three coping materials: i) metal alloy (MA), ii) zirconia oxide (ZO), and iii) lithium disilicate (LD) after various pre-surface treatments. Thirty-two (n = 32) discs were prepared for each coping material. Four pre-surface treatments were prepared for each sub-group (n = 8); a) no treatment or control (C), b) sandblast (SB), c) acid etch (AE), and d) sandblast and acid etch (SBAE). Veneering ceramics were applied to all discs. Shear bond strength was measured with a universal testing machine. Data were analyzed with two-way ANOVA and Tukey's multiple comparisons tests. Mean shear bond strengths were obtained for MA (19.00 ± 6.39 MPa), ZO (24.45 ± 5.14 MPa) and LD (13.62 ± 5.12 MPa). There were statistically significant differences in types of coping material and various pre-surface treatments ( P veneering ceramic to zirconia oxide was higher than metal alloy and lithium disilicate. The highest shear bond strengths were obtained in sandblast and acid etch treatment for zirconia oxide and lithium disilicate groups, and in acid etch treatment for metal alloy group.

  16. Nearly Perfect Durable Superhydrophobic Surfaces Fabricated by a Simple One-Step Plasma Treatment.

    Science.gov (United States)

    Ryu, Jeongeun; Kim, Kiwoong; Park, JooYoung; Hwang, Bae Geun; Ko, YoungChul; Kim, HyunJoo; Han, JeongSu; Seo, EungRyeol; Park, YongJong; Lee, Sang Joon

    2017-05-16

    Fabrication of superhydrophobic surfaces is an area of great interest because it can be applicable to various engineering fields. A simple, safe and inexpensive fabrication process is required to fabricate applicable superhydrophobic surfaces. In this study, we developed a facile fabrication method of nearly perfect superhydrophobic surfaces through plasma treatment with argon and oxygen gases. A polytetrafluoroethylene (PTFE) sheet was selected as a substrate material. We optimized the fabrication parameters to produce superhydrophobic surfaces of superior performance using the Taguchi method. The contact angle of the pristine PTFE surface is approximately 111.0° ± 2.4°, with a sliding angle of 12.3° ± 6.4°. After the plasma treatment, nano-sized spherical tips, which looked like crown-structures, were created. This PTFE sheet exhibits the maximum contact angle of 178.9°, with a sliding angle less than 1°. As a result, this superhydrophobic surface requires a small external force to detach water droplets dripped on the surface. The contact angle of the fabricated superhydrophobic surface is almost retained, even after performing an air-aging test for 80 days and a droplet impacting test for 6 h. This fabrication method can provide superb superhydrophobic surface using simple one-step plasma etching.

  17. Effects of surface treatment on bond strength between dental resin agent and zirconia ceramic

    International Nuclear Information System (INIS)

    Moradabadi, Ashkan; Roudsari, Sareh Esmaeily Sabet; Yekta, Bijan Eftekhari; Rahbar, Nima

    2014-01-01

    This paper presents the results of an experimental study to understand the dominant mechanism in bond strength between dental resin agent and zirconia ceramic by investigating the effects of different surface treatments. Effects of two major mechanisms of chemical and micromechanical adhesion were evaluated on bond strength of zirconia to luting agent. Specimens of yttrium-oxide-partially-stabilized zirconia blocks were fabricated. Seven groups of specimens with different surface treatment were prepared. 1) zirconia specimens after airborne particle abrasion (SZ), 2) zirconia specimens after etching (ZH), 3) zirconia specimens after airborne particle abrasion and simultaneous etching (HSZ), 4) zirconia specimens coated with a layer of a Fluorapatite-Leucite glaze (GZ), 5) GZ specimens with additional acid etching (HGZ), 6) zirconia specimens coated with a layer of salt glaze (SGZ) and 7) SGZ specimens after etching with 2% HCl (HSGZ). Composite cylinders were bonded to airborne-particle-abraded surfaces of ZirkonZahn specimens with Panavia F2 resin luting agent. Failure modes were examined under 30 × magnification and the effect of surface treatments was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). SZ and HSZ groups had the highest and GZ and SGZ groups had the lowest mean shear bond strengths among all groups. Mean shear bond strengths were significantly decreased by applying a glaze layer on zirconia surfaces in GZ and SGZ groups. However, bond strengths were improved after etching process. Airborne particle abrasion resulted in higher shear bond strengths compared to etching treatment. Modes of failure varied among different groups. Finally, it is concluded that micromechanical adhesion was a more effective mechanism than chemical adhesion and airborne particle abrasion significantly increased mean shear bond strengths compared with another surface treatments. - Highlights: • Understanding the dominant mechanism of bonding

  18. Effects of surface treatment on bond strength between dental resin agent and zirconia ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Moradabadi, Ashkan [Department of Electrochemistry, Universität Ulm, Ulm (Germany); Roudsari, Sareh Esmaeily Sabet [Department of Optoelectonics, Universität Ulm, Ulm (Germany); Yekta, Bijan Eftekhari [School of Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Rahbar, Nima, E-mail: nrahbar@wpi.edu [Department of Civil and Environmental Engineering, Worcester Polytechnic Institute, Worcester, MA 01609 (United States)

    2014-01-01

    This paper presents the results of an experimental study to understand the dominant mechanism in bond strength between dental resin agent and zirconia ceramic by investigating the effects of different surface treatments. Effects of two major mechanisms of chemical and micromechanical adhesion were evaluated on bond strength of zirconia to luting agent. Specimens of yttrium-oxide-partially-stabilized zirconia blocks were fabricated. Seven groups of specimens with different surface treatment were prepared. 1) zirconia specimens after airborne particle abrasion (SZ), 2) zirconia specimens after etching (ZH), 3) zirconia specimens after airborne particle abrasion and simultaneous etching (HSZ), 4) zirconia specimens coated with a layer of a Fluorapatite-Leucite glaze (GZ), 5) GZ specimens with additional acid etching (HGZ), 6) zirconia specimens coated with a layer of salt glaze (SGZ) and 7) SGZ specimens after etching with 2% HCl (HSGZ). Composite cylinders were bonded to airborne-particle-abraded surfaces of ZirkonZahn specimens with Panavia F2 resin luting agent. Failure modes were examined under 30 × magnification and the effect of surface treatments was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). SZ and HSZ groups had the highest and GZ and SGZ groups had the lowest mean shear bond strengths among all groups. Mean shear bond strengths were significantly decreased by applying a glaze layer on zirconia surfaces in GZ and SGZ groups. However, bond strengths were improved after etching process. Airborne particle abrasion resulted in higher shear bond strengths compared to etching treatment. Modes of failure varied among different groups. Finally, it is concluded that micromechanical adhesion was a more effective mechanism than chemical adhesion and airborne particle abrasion significantly increased mean shear bond strengths compared with another surface treatments. - Highlights: • Understanding the dominant mechanism of bonding

  19. Surface treatment of polyethylene terephthalate film using atmospheric pressure glow discharge in air

    International Nuclear Information System (INIS)

    Fang Zhi; Qiu Yuchang; Wang Hui

    2004-01-01

    Non-thermal plasmas under atmospheric pressure are of great interest in polymer surface processing because of their convenience, effectiveness and low cost. In this paper, the treatment of Polyethylene terephthalate (PET) film surface for improving hydrophilicity using the non-thermal plasma generated by atmospheric pressure glow discharge (APGD) in air is conducted. The discharge characteristics of APGD are shown by measurement of their electrical discharge parameters and observation of light-emission phenomena, and the surface properties of PET before and after the APGD treatment are studied using contact angle measurement, x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). It is found that the APGD is homogeneous and stable in the whole gas gap, which differs from the commonly filamentary dielectric barrier discharge (DBD). A short time (several seconds) APGD treatment can modify the surface characteristics of PET film markedly and uniformly. After 10 s APGD treatment, the surface oxygen content of PET surface increases to 39%, and the water contact angle decreases to 19 degree, respectively. (authors)

  20. Surface characterization of the chitosan membrane after oxygen plasma treatment and its aging effect

    International Nuclear Information System (INIS)

    Wang Yingjun; Yin Shiheng; Ren Li; Zhao Lianna

    2009-01-01

    Chitosan has received considerable attention for biomedical applications in recent years because of its biocompatibility and biodegradability. In this paper, angle-resolved x-ray photoelectron spectroscopy (ARXPS) was carried out to investigate the chemical groups' spatial orientation on the chitosan membrane surface. Oxygen plasma treatment was also employed to improve the surface hydrophilicity of the chitosan membrane. The results of ARXPS revealed the distribution of surface polar groups, such as-OH and O=CNH 2 toward the membrane bulk, which was the origin of the chitosan membrane surface hydrophobicity. The contact angle measurements and XPS results indicated that oxygen plasma treatment can markedly improve the surface hydrophilicity and surface energy of the chitosan membrane by incorporating oxygen-containing polar groups. With the existence of the aging process, the influence of plasma treatment was not permanent, it faded with storage time. The ARXPS result discovered that the reorientation of polar functional groups generated by plasma treatment toward the membrane bulk was primarily responsible for the aging effect.

  1. Surface Treatment of Polypropylene Films Using Dielectric Barrier Discharge with Magnetic Field

    International Nuclear Information System (INIS)

    Wang Changquan; Zhang Guixin; Wang Xinxin; Chen Zhiyu

    2012-01-01

    Atmospheric pressure non-thermal plasma is of interest for industrial applications. In this study, polypropylene (PP) films are modified by a dielectric barrier discharge (DBD) with a non-uniform magnetic field in air at atmospheric pressure. The surface properties of the PP films before and after a DBD treatment are studied by using contact angle measurement, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The effect of treatment time on the surface modification with and without a magnetic field is investigated. It is found that the hydrophilic improvement depends on the treatment time and magnetic field. It is also found that surface roughness and oxygen-containing groups are introduced onto the PP film surface after the DBD treatment. Surface roughness and oxygen-containing polar functional groups of the PP films increase with the magnetic induction density. The functional groups are identified as C-O, C=O and O-C=O by using XPS analysis. It is concluded that the hydrophilic improvement of PP films treated with a magnetic field is due to a greater surface roughness and more oxygen-containing groups. (plasma technology)

  2. A study of laser surface treatment in bonded repair of composite aircraft structures.

    Science.gov (United States)

    Li, Shaolong; Sun, Ting; Liu, Chang; Yang, Wenfeng; Tang, Qingru

    2018-03-01

    Surface pre-treatment is one of the key processes in bonded repair of aircraft carbon fibre reinforced polymer composites. This paper investigates the surface modification of physical and chemical properties by laser ablation and conventional polish treatment techniques. Surface morphology analysed by laser scanning confocal microscopy and scanning electron microscopy showed that a laser-treated surface displayed higher roughness than that of a polish-treated specimen. The laser-treated laminate exhibited more functional groups in the form of O 1 s/C 1 s atomic ratio of 30.89% for laser-treated and 20.14% for polish-treated as evidenced by X-ray photoelectron spectroscopy observation. Contact angle goniometry demonstrated that laser treatment can provide increased surface free energy and wettability. In the light of mechanical interlocking, molecular bonding and thermodynamics theories on adhesion, laser etching process displayed enhanced bonding performance relative to the polishing surface treatment. These properties resulted in an increased single lap shear strength and a cohesive failure mode for laser etching while an adhesive failure mode occurred in polish-treated specimen.

  3. Tuning Surface Chemistry of Polyetheretherketone by Gold Coating and Plasma Treatment

    Science.gov (United States)

    Novotná, Zdeňka; Rimpelová, Silvie; Juřík, Petr; Veselý, Martin; Kolská, Zdeňka; Hubáček, Tomáš; Borovec, Jakub; Švorčík, Václav

    2017-06-01

    Polyetheretherketone (PEEK) has good chemical and biomechanical properties that are excellent for biomedical applications. However, PEEK exhibits hydrophobic and other surface characteristics which cause limited cell adhesion. We have investigated the potential of Ar plasma treatment for the formation of a nanostructured PEEK surface in order to enhance cell adhesion. The specific aim of this study was to reveal the effect of the interface of plasma-treated and gold-coated PEEK matrices on adhesion and spreading of mouse embryonic fibroblasts. The surface characteristics (polarity, surface chemistry, and structure) before and after treatment were evaluated by various experimental techniques (gravimetry, goniometry, X-ray photoelectron spectroscopy (XPS), and electrokinetic analysis). Further, atomic force microscopy (AFM) was employed to examine PEEK surface morphology and roughness. The biological response of cells towards nanostructured PEEK was evaluated in terms of cell adhesion, spreading, and proliferation. Detailed cell morphology was evaluated by scanning electron microscopy (SEM). Compared to plasma treatment, gold coating improved PEEK wettability. The XPS method showed a decrease in the carbon concentration with increasing time of plasma treatment. Cell adhesion determined on the interface between plasma-treated and gold-coated PEEK matrices was directly proportional to the thickness of a gold layer on a sample. Our results suggest that plasma treatment in a combination with gold coating could be used in biomedical applications requiring enhanced cell adhesion.

  4. Effect of Enamel and Dentin Surface Treatment on the Self-Adhesive Resin Cement Bond Strength.

    Science.gov (United States)

    Mushashe, Amanda Mahmmad; Gonzaga, Carla Castiglia; Cunha, Leonardo Fernandes da; Furuse, Adilson Yoshio; Moro, Alexandre; Correr, Gisele Maria

    2016-01-01

    The aim of this study was to evaluate the effect of enamel and dentin surface treatment on the micro-shear bond strength of self-adhesive cement. Seventy-two extracted third molars had their crowns embedded in acrylic resin and worn to obtain a flat enamel or dentin surface. The enamel and dentin specimens were randomly assigned to 8 groups (n=12) that were based on surface treatment (11.5% polyacrylic acid solution or no treatment), substrate condition (wet or dry) and storage period (1 day or 90 days), and treated accordingly. Cylinders (1 × 1 mm) were fabricated using self-adhesive resin cement (RelyX U200) following the manufacturer's instructions. The specimens were stored in distilled water at 37 °C for either 1 day or 90 days and subjected to micro-shear bond strength test (EMIC DL 2000 at 0.5 mm/min). After this, the failure type of the specimens was determined. Data were subjected to statistical analysis (a=0.05). According to the results, the 11.5% polyacrylic acid application decreased the bond strength in both enamel and dentin samples. The moist groups showed higher bond strength than the dry ones, regardless of the substrate and surface treatment. Storage period did not influence bond strength. In conclusion, surface treatment with 11.5% polyacrylic acid and absence of moisture decreased the bond strength of the resin-cement (RelyU200), regardless of the storage period.

  5. Tuning Surface Chemistry of Polyetheretherketone by Gold Coating and Plasma Treatment.

    Science.gov (United States)

    Novotná, Zdeňka; Rimpelová, Silvie; Juřík, Petr; Veselý, Martin; Kolská, Zdeňka; Hubáček, Tomáš; Borovec, Jakub; Švorčík, Václav

    2017-12-01

    Polyetheretherketone (PEEK) has good chemical and biomechanical properties that are excellent for biomedical applications. However, PEEK exhibits hydrophobic and other surface characteristics which cause limited cell adhesion. We have investigated the potential of Ar plasma treatment for the formation of a nanostructured PEEK surface in order to enhance cell adhesion. The specific aim of this study was to reveal the effect of the interface of plasma-treated and gold-coated PEEK matrices on adhesion and spreading of mouse embryonic fibroblasts. The surface characteristics (polarity, surface chemistry, and structure) before and after treatment were evaluated by various experimental techniques (gravimetry, goniometry, X-ray photoelectron spectroscopy (XPS), and electrokinetic analysis). Further, atomic force microscopy (AFM) was employed to examine PEEK surface morphology and roughness. The biological response of cells towards nanostructured PEEK was evaluated in terms of cell adhesion, spreading, and proliferation. Detailed cell morphology was evaluated by scanning electron microscopy (SEM). Compared to plasma treatment, gold coating improved PEEK wettability. The XPS method showed a decrease in the carbon concentration with increasing time of plasma treatment. Cell adhesion determined on the interface between plasma-treated and gold-coated PEEK matrices was directly proportional to the thickness of a gold layer on a sample. Our results suggest that plasma treatment in a combination with gold coating could be used in biomedical applications requiring enhanced cell adhesion.

  6. Surface treatment of a titanium implant using low temperature atmospheric pressure plasmas

    Science.gov (United States)

    Lee, Hyun-Young; Tang, Tianyu; Ok, Jung-Woo; Kim, Dong-Hyun; Lee, Ho-Jun; Lee, Hae June

    2015-09-01

    During the last two decades, atmospheric pressure plasmas(APP) are widely used in diverse fields of biomedical applications, reduction of pollutants, and surface treatment of materials. Applications of APP to titanium surface of dental implants is steadily increasing as it renders surfaces wettability and modifies the oxide layer of titanium that hinders the interaction with cells and proteins. In this study, we have treated the titanium surfaces of screw-shaped implant samples using a plasma jet which is composed of a ceramic coaxial tube of dielectrics, a stainless steel inner electrode, and a coper tube outer electrode. The plasma ignition occurred with Ar gas flow between two coaxial metal electrodes and a sinusoidal bias voltage of 3 kV with a frequency of 20 kHz. Titanium materials used in this study are screw-shaped implants of which diameter and length are 5 mm and 13 mm, respectively. Samples were mounted at a distance of 5 mm below the plasma source, and the plasma treatment time was set to 3 min. The wettability of titanium surface was measured by the moving speed of water on its surface, which is enhanced by plasma treatment. The surface roughness was also measured by atomic force microscopy. The optimal condition for wettability change is discussed.

  7. Optical properties study of silicone polymer PDMS substrate surfaces modified by plasma treatment

    Science.gov (United States)

    Zahid, A.; Dai, B.; Hong, R.; Zhang, D.

    2017-10-01

    In this study, PDMS (polydimethylsiloxane) substrates with a half-plain, half-rough surface were prepared on a plain and rough fused silica glass substrate using a molding technique. The molded PDMS surface morphology was changed into a half-smooth and half-rough surface after peeling. The modified PDMS surfaces’ optical properties were inspected with and without treatment. The treatment is exposed by oxygen plasma (15 W) for 3 min in a vacuum, down to a pressure of six torr, using a vacuum pump. An atomic force microscope (AMF) and interferometer (white light) indicated that the plasma O2 treatment increased the formation of the plain surface and decreased the formation of the rough surface. The optical properties via a spectrophotometer (lambda) show the resonance from 300 nm to 1200 nm on the rough surface, which is considered to be a faithful reproduction for transmittance and reflectance. The Raman spectra and FDTD simulation results are in excellent agreement; not to be confused with metal local surface plasmon resonances (LSPRs). The Raman spectra peaks and hotspot are the results of the PDMS Si-O backbone. The PDMS substrate presented the diversity of the optical properties, which makes the substrate complementary to various optical applications.

  8. Effect of mineral trioxide aggregate surface treatments on morphology and bond strength to composite resin.

    Science.gov (United States)

    Shin, Joo-Hee; Jang, Ji-Hyun; Park, Sang Hyuk; Kim, Euiseong

    2014-08-01

    The aim of this study was to evaluate the micromorphologic changes that accompany different surface treatments on mineral trioxide aggregate (MTA) and their effect on the bond strength to the composite resin with 4 adhesive systems. Three types of MTA cement, ProRoot MTA (WMTA) (Dentsply, Tulsa, OK), MTA Angelus (AMTA) (Angelus, Londrina, PR, Brazil), and Endocem MTA (EMTA) (Maruchi, Wonju, Korea), were prepared and stored for a week to encourage setting. Surface treatment was performed using phosphoric acid or self-etch primer, and an untreated MTA surface was prepared as a control. The surface changes were observed using scanning electron microscopy. MTA surfaces were bonded with 4 adhesive systems, including Scotchbond Multipurpose (3M ESPE, St Paul, MN), Single Bond 2 (3M ESPE), Clearfil SE BOND (Kuraray, Osaka, Japan), and AdheSE One F (Ivoclar Vivadent, Schaan, Liechtenstein), to evaluate the adhesive effectiveness of MTA followed by composite resin restoration. The shear bond strength of the polymerized specimens was tested. For WMTA and AMTA, untreated surfaces showed an irregular crystalline plate with clusters of globular aggregate particles. For EMTA, the untreated surface presented a reticular matrix with acicular crystals. After surface treatment, superficial crystalline structures were eroded regardless of the MTA cement and adhesive system used. WMTA bonded significantly more strongly than AMTA and EMTA, regardless of the adhesive system used. In the WMTA and AMTA groups, AdheSE One F showed the highest bond strength to the composite. For EMTA, no significant differences were found across adhesive systems. Acidic treatment of the MTA surface affected the micromorphology and the bond strength to the composite. Within the limitations of this study, using a 1-step self-etch adhesive system might result in a strong bond to WMTA when the composite resin restoration is required over MTA cement. Copyright © 2014 American Association of Endodontists

  9. High Conductivity Water Treatment Using Water Surface Discharge with Nonmetallic Electrodes

    International Nuclear Information System (INIS)

    Wang Xiaoping; Zhang Xingwang; Lei Lecheng

    2013-01-01

    Although electrohydraulic discharge is effective for wastewater treatment, its application is restricted by water conductivity and limited to the treatment of low conductivity water. For high conductivity water treatment, water-surface discharge is the preferred choice. However, the metallic electrodes are easily corroded because of the high temperature and strong oxidative environment caused by gas phase discharge and the electrochemical reaction in water. As a result, the efficiency of the water treatment might be affected and the service life of the reactor might be shortened. In order to avoid the corrosion problem, nonmetallic electrode water-surface discharge is introduced into high conductivity water treatment in the present study. Carbon-felt and water were used as the high voltage electrode and ground electrode, respectively. A comparison of the electrical and chemical characteristics showed that nonmetallic electrode discharge maintained the discharge characteristics and enhanced the energy efficiency, and furthermore, the corrosion of metal electrodes was avoided.

  10. Evaluation of Ti-6Al-4V surface treatments for use with a polyphenylquinoxaline adhesive

    Science.gov (United States)

    Progar, Donald J.

    1987-01-01

    Three surface treatments for Ti-6Al-4V adherends were evaluated using a thermoplastic polymer monoether polyphenylquinoxaline, MEPPQ, which had been shown in previous studies to have good potential as a high temperature adhesive for aerospace applications. Initial results based on long term thermal exposure at 232 C (450 F) using the phosphate-fluoride (PF) and chromic acid anodized (CAA) treatments with MEPPQ adhesive were not encouraging. A significant improvement in strength retention and a change in failure mode (cohesive) at 232 C (450 F) was found for the SHA treated specimens compared to the PF and CAA treatments. Although an improvement in long term thermal durability was obtained with the SHA treatment of Ti-6Al-4V, an improved surface treatment with better long term durability is still required for aerospace applications.

  11. DEPOSITIONAL ENVIRONMENT AND ORGANIC GEOCHEMICAL CHARACTERISTICS OF LOWER EOCENE BITUMINOUS ROCKS, IN THE KÜRNÜÇ/GÖYNÜK-BOLU AREA

    Directory of Open Access Journals (Sweden)

    Ali SARI

    2016-12-01

    Full Text Available In this study, dark gray and dark brown colored, organic-carbon rich bituminous rocks (bituminous marl and bituminous shale exposing around the Kürnüç area (Göynük, Bolu are investigated by means of or- ganic geochemical characteristics. In this respect, rock lithologies, depositional environments, rock source potential, kerogen and organic maturity types and hydrocarbon generation potentials of bituminous rocks were determined. For this reason, pyrolysis (Rock Eval–VI analysis, gas chromatography (GC and gas chromatography-mass spectrometer (GC-MS analyses were carried out. In addition, spore color index (SCI was determined with organic petrographic method and stable carbon analysis (δ13C of the samples were also conducted. Lithology of the studied samples is of clastic source and the depositional environ- ment is a lagoon with a partial connection to the sea. In bituminous rocks with excellent source rock potential TOC values are in the range of 2.52-8.38 wt % (average 6.08 wt %. With the exception of two samples (Type II kerogen type of all samples is Type I. According to pyrolysis, GC and GC-MS organic maturity results, all the samples are in immature stage. Organic geochemical data indicate that bituminous rocks have an excellent oil generation potential and there is no organic contamination.

  12. Effect of different surface treatments on the shear bond strength of nanofilled composite repairs

    Directory of Open Access Journals (Sweden)

    Ghazaleh Ahmadizenouz

    2016-03-01

    Full Text Available Background. Repairing aged composite resin is a challenging process. Many surface treatment options have been proposed to this end. This study evaluated the effect of different surface treatments on the shear bond strength (SBS of nano-filled composite resin repairs. Methods. Seventy-five cylindrical specimens of a Filtek Z350XT composite resin were fabricated and stored in 37°C distilled water for 24 hours. After thermocycling, the specimens were divided into 5 groups according to the following surface treatments: no treatment (group 1; air abrasion with 50-μm aluminum oxide particles (group 2; irradiation with Er:YAG laser beams (group 3; roughening with coarse-grit diamond bur + 35% phosphoric acid (group 4; and etching with 9% hydrofluoric acid for 120 s (group 5. Another group of Filtek Z350XT composite resin samples (4×6 mm was fabricated for the measurement of cohesive strength (group 6. A silane coupling agent and an adhesive system were applied after each surface treatment. The specimens were restored with the same composite resin and thermocycled again. A shearing force was applied to the interface in a universal testing machine. Data were analyzed using one-way ANOVA and post hoc Tukey tests (P < 0.05. Results. One-way ANOVA indicated significant differences between the groups (P < 0.05. SBS of controls was significantly lower than the other groups; differences between groups 2, 3, 4, 5 and 6 were not significant. Surface treatment with diamond bur + 35% phosphoric acid resulted in the highest bond strength. Conclusion. All the surface treatments used in this study improved the shear bond strength of nanofilled composite resin used.

  13. Assessment of a chair-side argon-based non-thermal plasma treatment on the surface characteristics and integration of dental implants with textured surfaces.

    Science.gov (United States)

    Teixeira, Hellen S; Marin, Charles; Witek, Lukasz; Freitas, Amilcar; Silva, Nelson R F; Lilin, Thomas; Tovar, Nick; Janal, Malvin N; Coelho, Paulo G

    2012-05-01

    The biomechanical effects of a non-thermal plasma (NTP) treatment, suitable for use in a dental office, on the surface character and integration of a textured dental implant surface in a beagle dog model were evaluated. The experiment compared a control treatment, which presented an alumina-blasted/acid-etched (AB/AE) surface, to two experimental treatments, in which the same AB/AE surface also received NTP treatment for a period of 20 or 60 s per implant quadrant (PLASMA 20' and PLASMA 60' groups, respectively). The surface of each specimen was characterized by electron microscopy and optical interferometry, and surface energy and surface chemistry were determined prior to and after plasma treatment. Two implants of each type were then placed at six bilateral locations in 6 dogs, and allowed to heal for 2 or 4 weeks. Following sacrifice, removal torque was evaluated as a function of animal, implant surface and time in vivo in a mixed model ANOVA. Compared to the CONTROL group, PLASMA 20' and 60' groups presented substantially higher surface energy levels, lower amounts of adsorbed C species and significantly higher torque levels (p=.001). Result indicated that the NTP treatment increased the surface energy and the biomechanical fixation of textured-surface dental implants at early times in vivo. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Surface characteristics of bioactive Ti fabricated by chemical treatment for cartilaginous-integration.

    Science.gov (United States)

    Miyajima, Hiroyuki; Ozer, Fusun; Imazato, Satoshi; Mante, Francis K

    2017-09-01

    Artificial hip joints are generally expected to fail due to wear after approximately 15years and then have to be replaced by revision surgery. If articular cartilage can be integrated onto the articular surfaces of artificial joints in the same way as osseo-integration of titanium dental implants, the wear of joint implants may be reduced or prevented. However, very few studies have focused on the relationship between Ti surface and cartilage. To explore the possibility of cartilaginous-integration, we fabricated chemically treated Ti surfaces with H 2 O 2 /HCl, collagen type II and SBF, respectively. Then, we evaluated surface characteristics of the prepared Ti samples and assessed the cartilage formation by culturing chondrocytes on the Ti samples. When oxidized Ti was immersed in SBF for 7days, apatite was formed on the Ti surface. The surface characteristics of Ti indicated that the wettability was increased by all chemical treatments compared to untreated Ti, and that H 2 O 2 /HCl treated surface had significantly higher roughness compared to the other three groups. Chondrocytes produced significantly more cartilage matrix on all chemically treated Ti surfaces compared to untreated Ti. Thus, to realize cartilaginous-integration and to prevent wear of the implants in joints, application of bioactive Ti formed by chemical treatment would be a promising and effective strategy to improve durability of joint replacement. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. APPLICATION OF CHEMICAL PRE-TREATMENT ON THE POLISHED SURFACE OF ALUMINIUM ALLOYS

    Directory of Open Access Journals (Sweden)

    Pavel Kraus

    2016-12-01

    Full Text Available This paper reports the preparation and characterization of thin transparent nanolayers with phase composition ZrF4 and different modification of SiO2 with special focus on affecting the surface roughness of the material and the way of exclusion of the thin nanolayer on the surface of the polished aluminium material. The thin nanolayer was prepared by the sol-gel method. The final treatment based on PTFE was applied on the surface of some samples. This treatment is suitable for increasing wear resistance. The films were characterized with help of SEM microscopy and EDS analysis. The surface roughness was measured with classical surface roughness tester. The results on this theme have already published but not on the polished surface of the aluminium material. The results from the experiment show the problems with application of these nanolayers because a cracks were found on the surface of the material and deformations of the layer after application of the PTFE final layer. The surface layer formation is discussed.

  16. Processing of a Silesian bituminous coal tar mixture at 600 atm to heavy oil excess in a 10-liter oven

    Energy Technology Data Exchange (ETDEWEB)

    Hupfer, H.

    1942-10-28

    An analysis was made of a bituminous coal tar mixture for consideration as raw material for Blechhammer. A breakdown of the composition and yield charts is provided. A table compared it to a coke tar pitch and a bituminous tar mixture from a different carbonization process and its yields were approximately between the yield values of these two. Although the sludge extraction produced sufficient yields in the experiment, the yields would not be as good within full-scale industry. A day by day progress description of the experimentation is provided including all operational details. The experimental results and the pros and cons are summarized briefly. Fifteen tables of data provide analysis of all the elements tested.

  17. Enhancement of the Laser Transmission Weldability between Polyethylene and Polyoxymethylene by Plasma Surface Treatment

    Directory of Open Access Journals (Sweden)

    Huixia Liu

    2017-12-01

    Full Text Available Due to their large compatibility difference, polyethylene (PE and polyoxymethylene (POM cannot be welded together by laser transmission welding. In this study, PE and POM are pretreated using plasma that significantly enhances their laser transmission welding strength. To understand the mechanism underlying the laser welding strength enhancement, surface modification is analyzed using contact angle measurements, atomic force microscopy (AFM, optical microscopy, and X-ray photoelectron spectroscopy (XPS. Characterization results show that the plasma surface treatment improves the surface free energy, significantly enhancing the wettability of the materials. The increase in surface roughness and the generation of homogeneous bubbles contribute to the formation of mechanical micro-interlocking. The oxygen-containing groups introduced by the oxygen plasma treatment improve the compatibility of PE and POM, and facilitate the diffusion and entanglement of molecular chains and the formation of van der Waals force.

  18. On ultrahigh-vacuum preparation of monocrystalline transition metal surfaces by heat treatment

    CERN Document Server

    Krakhmalev, V A; Nimatov, S J; Garafutdinova, I A; Boltaev, N N

    2002-01-01

    The composition and substructure changes in monocrystalline singular W, Mo, Nb surfaces under heat treatment have been studied in the range 30-1900 sup d egC and vacuum approx 5 centre dot 10 sup - sup 8 Pa by electronic Auger spectroscopy, optical microscopy, and X-ray methods. Under multiple thermal-cycled treatment the large carbide inclusions have been found to become the places of local surface polygonization with block disordering >=3 sup d eg. In the case of Nb annealing the carbide in the O sub 2 atmosphere has led to solving O sub 2 in sample volume. In what follows, the solute O sub 2 is found to diffuse to on the surface under heating up to maximal temperatures of the above range. Under 30 min annealing of Nb(110) at approx 550 sup d egC, sulphur (S sub 1 sub 5 sub 2) segregation on surface appears that increases with temperature. (author)

  19. Corrosion resistance of the welded AISI 316L after various surface treatments

    Directory of Open Access Journals (Sweden)

    Tatiana Liptáková

    2014-01-01

    Full Text Available The main aim of this work is to monitor the surface treatment impact on the corrosion resistance of the welded stainless steel AISI 316L to local corrosion forms. The excellent corrosion resistance of austenitic stainless steel is caused by the existence of stable, thin and well adhering passive layer which quality is strongly influenced by welding. Therefore surface treatment of stainless steel is very important with regard to its local corrosion susceptibility Surfaces of welded stainless steel were treated by various mechanical methods (grinding, garnet blasting. Surface properties were studied by SEM, corrosion resistance was evaluated after exposition tests in chlorides environment using weight and metalographic analysis. The experimental outcomes confirmed that the mechanical finishing has a significant effect on the corrosion behavior of welded stainless steel AISI 316L.

  20. Wear Resistance of Steels with Surface Nanocrystalline Structure Generated by Mechanical-Pulse Treatment.

    Science.gov (United States)

    Nykyforchyn, Hryhoriy; Kyryliv, Volodymyr; Maksymiv, Olha

    2017-12-01

    The influence of the surface mechanical-pulse treatment based on high-speed friction with a rapid cooling by the technological environment on the wear resistance of medium- and high-carbon steels was considered. The treatment due to a severe plastic deformation enabled obtaining the nanocrystalline structure with a grain size of 14-40 nm. A high positive effect of this treatment was obtained not only because of metal nanocrystallization but also thanks to other factors, namely, structural-phase transformations, carbon saturation of the surface due to decomposition of the coolant and the friction coefficient decrease. Higher carbon content leads to better strengthening of the surface, and its microhardness can reach 12 GPa.

  1. Gliding arc surface treatment of glass-fiber-reinforced polyester enhanced by ultrasonic irradiation

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Norrman, Kion; Drews, Joanna Maria

    2011-01-01

    . The efficiency of such a plasma treatment at atmospheric pressure can be further improved by ultrasonic irradiation onto the surface during the treatment. In the present work glass fiber reinforced polyester (GFRP) plates are treated using an atmospheric pressure gliding arc with and without ultrasonic...... that ultrasonic irradiation reduced the OH rotational temperature of the gliding arc. The wettability of the GFRP surface was significantly improved by the plasma treatment without ultrasonic irradiation, and tended to improve furthermore at higher power to the plasma. Ultrasonic irradiation during the plasma......A gliding arc is a plasma generated between diverging electrodes and extended by a high speed gas flow. It can be operated in air at atmospheric pressure. It potentially enables selective chemical processing with high productivity, and is useful for adhesion improvement of material surfaces...

  2. Fuel-oils from co-pyrolysis of scrap tyres with coal and a bituminous waste. Influence of oven configuration

    OpenAIRE

    Acevedo Muñoz, Beatriz; Barriocanal Rueda, Carmen

    2014-01-01

    Two wastes from the tyre recycling industry – the fibers used as reinforcing material and tyre crumbs – were pyrolyzed in two ovens of different configuration. Blends with a low rank coal and a bituminous waste were also prepared to modify the composition of the oils obtained from the pyrolysis of the tyre wastes. Elemental analysis, calorific value, Fourier transform infrared spectroscopy (FTIR) and gas chromatography were used to determine the oil composition. A comparative study taking int...

  3. Analysis of the influence of chemical treatment to the strength and surface roughness of FDM

    Science.gov (United States)

    Hambali, R. H.; Cheong, K. M.; Azizan, N.

    2017-06-01

    The applications of Additive Manufacturing (AM) technology have a greater functionality and wider range of application beyond an intention of prototyping. AM is the process of joining materials to form objects from Computer-Aided Design (CAD) models via layer upon layer process. One of AM technologies is the Fused Deposition Modelling (FDM), which use an extrusion method to create a part. FDM has been applied in many manufacturing applications includes an end-used parts. However, FDM tends to have bad surface quality due to staircase effect and post treatment is required. This chemical treatment is one of a way to improve the surface roughness of FDM fabricated parts. This method is one of economical and faster method. In order to enhance the surface finish of Acrylonitrile-Butadiene-Styrene (ABS) FDM parts by performing chemical treatment in an acetone solution as acetone has very low toxicity, high diffusion and low cost chemical solution. Therefore, the aim of this research is to investigate the influence of chemical treatment to the FDM used part in terms of surface roughness as well as the strength. In this project, ten specimens of standard ASTM D638 dogbone specimens have been fabricated using MOJO 3D printer. Five specimens from the dogbone were tested for surface roughness and tensile testing while another five were immersed in the chemical solution before the same testing. Based on results, the surface roughness of chemically treated dogbone has dramatically improved, compared to untreated dogbone with 97.2% of improvement. However, in term of strength, the tensile strength of dogbone is reduced 42.58% due to the rearrange of material properties and chemical effects to the joining of the filaments. In conclusion, chemical treatment is an economical and sustainable approach to enhance the surface quality of AM parts.

  4. Potentialities inherent in high-energy surface treatment for corrosion protection of metals

    International Nuclear Information System (INIS)

    Kolotyrkin, V.I.; Knyazheva, V.M.

    1991-01-01

    Natural resources of alloying elements are limited. Application of protective coatings, surface alloying, modification of its structure make up one of the most important problems, successful solution of which will permit a sharp reduction of metal consumption, increase in the quality and service time of equipment and machines, increase in output per man - hour. Four high-energy methods of anticorrosion treatment of metal surface: gas-plasma, detonation, laser and electron-beam ones, are assessed in the review

  5. Influence of prophylaxis paste treatment on the abrasive wear of surface sealants.

    Science.gov (United States)

    Wegehaupt, Florian J; Tauböck, Tobias T; Attin, Thomas

    2013-01-01

    To investigate the abrasive wear of surface sealants (Seal&Protect and K-0184 (experimental sealant)) and the influence of pre-treatment with mineral deposit forming prophylaxis pastes (NUPRO Sensodyne and NUPRO) on this wear. One hundred and eight bovine dentine samples were randomly allocated to nine groups (1-9). Pre-treatment (10 s): groups 1-3: untreated, groups 4-6: NUPRO, groups 7-9: NUPRO Sensodyne. Sealing: groups 1, 4 and 7: unsealed, groups 2, 5 and 8: Seal&Protect, groups 3, 6 and 9: K-0184 (experimental sealer). Samples were then brushed with 12 000 brushing strokes (BS) with toothpaste slurry in an automatic brushing machine (120 BS/min; F = 2.5 N). Surface profiles were recorded at baseline, after pre-treatment and sealing and after each 2000 BS. Total profile change (wear or gain due to pre-treatment, treatment and 12 000 BS): groups 1, 4 and 7 (no surface sealant) showed a not significantly different wear of 18.48 ± 2.63 µm, 24.98 ± 3.02 µm and 21.50 ± 5.47 µm, respectively. Remaining groups (sealed) showed a gain in height with no significant difference among each other. Wear in sealed groups (2, 3, 5, 6, 8 and 9) were not significantly different at all numbers of brushing strokes. Starting with 4000 BS, the wear in unsealed groups (1, 4 and 7) was statistically significantly higher compared to all other groups. Stability and wear resistance of surface sealants are not affected by pre-treatment of dentine with NUPRO Sensodyne. The surface sealants tested provide a stable protective surface layer on dentine, which lasts for at least 12 000 brushing strokes.

  6. Effect of surface treatment of prefabricated teeth on shear bond strength of orthodontic brackets

    Science.gov (United States)

    Cumerlato, Marina; de Lima, Eduardo Martinelli; Osorio, Leandro Berni; Mota, Eduardo Gonçalves; de Menezes, Luciane Macedo; Rizzatto, Susana Maria Deon

    2017-01-01

    ABSTRACT Objective: The aim of this in vitro study was to evaluate and compare the effects of grinding, drilling, sandblasting, and ageing prefabricated teeth (PfT) on the shear bond strength (SBS) of orthodontic brackets, as well as the effects of surface treatments on the adhesive remnant index (ARI). Methods: One-hundred-ninety-two PfT were divided into four groups (n = 48): Group 1, no surface treatment was done; Group 2, grinding was performed with a cylindrical diamond bur; Group 3, two drillings were done with a spherical diamond bur; Group 4, sandblasting was performed with 50-µm aluminum oxide. Before the experiment, half of the samples stayed immersed in distilled water at 37oC for 90 days. Brackets were bonded with Transbond XT and shear strength tests were carried out using a universal testing machine. SBS were compared by surface treatment and by ageing with two-way ANOVA, followed by Tukey’s test. ARI scores were compared between surface treatments with Kruskal-Wallis test followed by Dunn’s test. Results: Surface treatments on PfT enhanced SBS of brackets (p< 0.01), result not observed with ageing (p= 0.45). Groups II, III, and IV showed higher SBS and greater ARI than the Group 1 (p< 0.05). SBS was greater in the groups 3 and 4 (drilling, sandblasting) than in the Group 2 (grinding) (p< 0.05). SBS and ARI showed a positive correlation (Spearman’s R2= 0.57; p< 0.05). Conclusion: Surface treatment on PfT enhanced SBS of brackets, however ageing did not show any relevance. Sandblasting and drilling showed greater SBS than grinding. There was a positive correlation between SBS and ARI. PMID:28902249

  7. Effects of Er:YAG laser treatments on surface roughness of base metal alloys.

    Science.gov (United States)

    Kunt, Göknil Ergün; Güler, Ahmet Umut; Ceylan, Gözlem; Duran, Ibrahim; Ozkan, Pelin; Kirtiloğlu, Tuğrul

    2012-01-01

    We investigated the effects of different Er:YAG laser treatments on the surface roughness of base metal alloys. A total of 36 specimens were prepared of two base metal alloys (Wiron 99, Bellabond plus). The surfaces of the specimens were standardized by gradual wet grinding with 320-, 600-, 800- and 1,000-grit silicon carbide paper for 10 s each on a grinding machine at 300 rpm. Specimens of each alloy were randomly divided into six groups (n = 6) comprising a control group (group C), a group sandblasted with Al(2)O(3) powder at 60 psi for 10 s through a nozzle at a distance of 10 mm (group S), and four Er:YAG laser (Fotona AT) treatment groups. The laser treatment groups were as follows: 500 mJ, 10 Hz, 100 μs (group 500MSP); 500 mJ, 10 Hz, 300 μs (group 500SP); 400 mJ, 10 Hz, 100 μs (group 400MSP); and 400 mJ, 10 Hz, 300 μs (group 400SP). Surface roughness measurements (Ra) were performed using a profilometer. The data were analysed by two-way ANOVA, and mean values were compared using Tukey's HSD test (α = 0.05). According to the two-way ANOVA results, the base metal alloys and interaction between base metal alloy and surface treatment were not statistically significant different (p > 0.05), the surface treatments were significantly different (p metal alloy groups, no significant differences were observed among the control, 400MSP, and 400SP groups (p = 0.912), and these groups demonstrated the lowest Ra values. The highest Ra value was observed in group S (p laser treatment at 400 and 500 mJ/10 Hz is not an alternative method for surface roughening of base metal alloys.

  8. Surface-nitriding treatment of steels using microwave-induced nitrogen plasma at atmospheric pressure

    International Nuclear Information System (INIS)

    Sato, Shigeo; Arai, Yuuki; Yamashita, Noboru; Kojyo, Atsushi; Kodama, Kenji; Ohtsu, Naofumi; Okamoto, Yukio; Wagatsuma, Kazuaki

    2012-01-01

    A rapid surface-nitriding system using microwave-induced nitrogen plasma at atmospheric pressure was developed for modifying iron and steel surfaces. Since the conventional plasma nitriding technique requires a low-pressure atmosphere in the treatment chamber, the population of excited nitrogen molecules in the plasma is limited. Accordingly, several hours are required for nitriding treatment. By contrast, the developed nitriding system can use atmospheric-pressure plasma through application of the Okamoto cavity for excitation of nitrogen plasma. The high population of excited nitrogen molecules induced by the atmospheric-pressure plasma allowed the formation of a nitriding layer that was several micrometers thick within 1 min and produced an expanded austenite iron phase with a high nitrogen concentration close to the solubility limit on the iron substrate. In addition, the nitriding treatment on high-chromium steel was performed by introducing a reducing gas such as NH 3 and H 2 into the treatment chamber. While the nitriding reaction did not proceed in a simple N 2 atmosphere due to surface oxidation, the surface reduction induced by the NH 3 or H 2 gas promoted the nitriding reaction at the surface. These nitriding phenomena characteristics of the atmospheric-pressure plasma are discussed in this paper based on the effects of the specimen temperature and plasma atmosphere on the thickness, the chemical states, and the nitride compounds of the nitrided layer as investigated by X-ray diffraction, glow-discharge optical emission spectroscopy, and X-ray photoelectron spectroscopy.

  9. Effect of Surface Treatment Condition of Aminosilane on Ethylene Polymerization of Supported Metallocene

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Yun; Lee, Jeong Suk; Ko, Young Soo [Kongju National University, Cheonan (Korea, Republic of)

    2015-02-15

    The effects of surface treatment method of unreacted N-[3-(trimethoxysilyl)propyl]ethylenediamine (2NS), N{sup 1}-(3-trimethoxysilylpropyl)diethylenetriamine (3NS), and 3-cyanopropyltriethoxysilane (1NCy) after grafting on the surface of silica and of the surface treatment temperature on ethylene polymerization were investigated. The Zr content of supported catalyst employing filtering method was higher than that of washing method, and the activities of supported catalysts prepared by washing method were higher than those of filtering methods significantly. Regardless of surface treatment methods the activities were in order by SiO{sub 2}/2NS/(n-BuCp){sub 2}ZrCl{sub 2}>SiO{sub 2}/1NCy/(n-BuCp){sub 2}ZrCl{sub 2}>SiO{sub 2}/3NS/(n-BuCp){sub 2}ZrCl{sub 2}. The ethylene polymerization activity was increased as the surface treatment temperature of aminosilane on silica increased.

  10. Influence of zirconia surface treatment on veneering porcelain shear bond strength after cyclic loading.

    Science.gov (United States)

    Nishigori, Atsushi; Yoshida, Takamitsu; Bottino, Marco C; Platt, Jeffrey A

    2014-12-01

    The influence of yttria-stabilized tetragonal zirconia polycrystal surface treatment on veneering porcelain shear bond strength after cyclic loading is not fully understood. The purpose of this study was to investigate the influence of yttria-stabilized tetragonal zirconia polycrystal surface treatment on veneering porcelain shear bond strength and cyclic loading on the shear bond strength between the 2 materials. A total of 48 cylinder-shaped yttria-stabilized tetragonal zirconia polycrystal specimens were fabricated with computer-aided design and computer-aided manufacturing (CAD/CAM), sintered for 8 hours at 1500°C, ground with 320-grit diamond paper, and divided into 4 groups (n = 12) according to surface treatment as follows: no treatment/control; heat treatment of 650°C to 1000°C at 55°C/min; airborne-particle abrasion with 50-μm alumina at 0.4 MPa pressure for 10 seconds; or heat treatment after abrasion. A veneering porcelain cylinder was built and fired on the prepared yttria-stabilized tetragonal zirconia polycrystal specimens. The shear bond strength was tested with a universal testing machine. Six specimens from each group were subjected to cyclic loading (10000 cycles, 1.5 Hz, 10 N load) before testing. The mean ± SD ranged from 10.7 ± 15.4 to 34.1 ± 10.0. Three-way ANOVA found no statistically significant (P > .05) effect of surface treatment and cyclic loading on shear bond strength. The Sidak multiple comparisons procedure found that cyclic loading specimens had significantly lower shear bond strength than noncyclic loading specimens after airborne-particle abrasion without heat treatment (P = .013). Within the limitations of this study, the shear bond strength between yttria-stabilized tetragonal zirconia polycrystal and veneering porcelain was not significantly affected by surface treatment. Airborne-particle abrasion without subsequent heat treatment should be avoided as a surface treatment in fabrication methods. Copyright © 2014

  11. Bond strength of resin-resin interfaces contaminated with saliva and submitted to different surface treatments

    Directory of Open Access Journals (Sweden)

    Adilson Yoshio Furuse

    2007-12-01

    Full Text Available The purpose of this study was to investigate the effect of different surface treatments on shear bond strength of saliva-contaminated resin-resin interfaces. Flat resin surfaces were fabricated. In the control group, no contamination or surface treatment was performed. The resin surfaces of the experimental groups were contaminated with saliva and air-dried, and then submitted to: (G1 rinsing with water and drying; (G2 application of an adhesive system; (G3 rinsing and drying, abrasion with finishing disks, etching and application of adhesive system; (G4 rinsing and drying, etching, application of silane and adhesive system. Resin cylinders were placed over the treated surfaces. The specimens were stored in water or ethanol. Shear bond strength tests were performed and the mode of failure was evaluated. Data were submitted to two-way ANOVA and Dunnett T3 test. Contamination of resin-resin interfaces with saliva significantly reduced shear strength, especially after prolonged storage (p<0.05. Similar values to the original bond strength were obtained after abrasion and application of adhesive (G3 or etching and application of silane and adhesive (G4. If contamination occurs, a surface treatment is required to guarantee an adequate interaction between the resin increments.

  12. CO2 laser surface treatment of failed dental implants for re-implantation: an animal study.

    Science.gov (United States)

    Kasraei, Shahin; Torkzaban, Parviz; Shams, Bahar; Hosseinipanah, Seyed Mohammad; Farhadian, Maryam

    2016-07-01

    The aim of the present study was to evaluate the success rate of failed implants re-implanted after surface treatment with CO2 laser. Despite the widespread use of dental implants, there are many incidents of failures. It is believed that lasers can be applied to decontaminate the implant surface without damaging the implant. Ten dental implants that had failed for various reasons other than fracture or surface abrasion were subjected to CO2 laser surface treatment and randomly placed in the maxillae of dogs. Three failed implants were also placed as the negative controls after irrigation with saline solution without laser surface treatment. The stability of the implants was evaluated by the use of the Periotest values (PTVs) on the first day after surgery and at 1, 3, and 6 months post-operatively. The mean PTVs of treated implants increased at the first month interval, indicating a decrease in implant stability due to inflammation followed by healing of the tissue. At 3 and 6 months, the mean PTVs decreased compared to the 1-month interval (P laser surface debridement is associated with a high success rate in terms of implant stability.

  13. Utilization of Waste Clay from Boron Production in Bituminous Geosynthetic Barrier (GBR-B Production as Landfill Liner

    Directory of Open Access Journals (Sweden)

    Müfide Banar

    2016-01-01

    Full Text Available Bituminous geomembranes, one type of geosynthetics, include a hot bituminous mixture with mineral filler and reinforcement. In this study, boron production waste clay (CW was used as filler to produce a geosynthetic barrier with bentonite, waste tire, and bitumen. Bentonite and waste tires were used as auxiliary fillers and bitumen as the binder. CW/bitumen, CW/bentonite/bitumen, and CW/waste tire/bitumen mixtures were prepared by using a laboratory mixer at 100°C. Hot mixtures were extruded into strips by using a lab-scale corotating twin screw extruder (L/D: 40 followed by die casting (2 mm × 100 mm. Glass fleece or nonwoven polyester was used as reinforcement material and while die casting, both sides of the reinforcement materials were covered with bituminous mixture. Thickness, mass per unit area, tensile strength, elongation at yield, and hydraulic conductivity were used to characterize the geomembranes. Among all geomembranes, nonwoven polyester covered with 30% bitumen-70% boron waste clay mixture (PK-BTM30CW70 was found to be the most promising in terms of structure and mechanical behaviour. After that, consequences of its exposure to distilled water (DW, municipal solid waste landfill leachate (L-MSW, and hazardous waste landfill leachate (L-HW were examined to use for an innovative impermeable liner on solid waste landfills.

  14. Modification of the x-ray diffraction efficiency of lithium fluoride crystals by surface treatment

    International Nuclear Information System (INIS)

    Sellick, B.O.

    1976-01-01

    Convex-curved crystals of lithium fluoride demonstrate good dispersion and efficiency when used in reflection for x-ray spectral analysis. The crystals are stable and reasonably unaffected by harsh environments. In addition, they are mechanically strong, easily cleavable or machinable, and plastically deformable with heat. In the present study, flat crystal wafers were left either clear as cleaved or were subjected to surface treatment by sandblasting or lapping. Some wafers were then bent in a press mold to obtain convex-curved crystals of differing radii. The diffraction efficiency data presented show how surface treatment affects the efficiency of these various crystals when used as x-ray diffracting agents

  15. Shear bond strength of veneering ceramic to zirconia core after different surface treatments.

    Science.gov (United States)

    Kirmali, Omer; Akin, Hakan; Ozdemir, Ali Kemal

    2013-06-01

    The aim of this study was to evaluate the effect of different surface treatments: sandblasting, liners, and different laser irradiations on shear bond strength (SBS) of pre-sintered zirconia to veneer ceramic. The SBS between veneering porcelain and zirconium oxide (ZrO2) substructure was weak. Various surface treatment methods have been suggested for zirconia to obtain high bond strength to veneering porcelain. There is no study that evaluated the bond strength between veneering porcelain and the different surface treatments on pre-sintered ZrO2 substructure. Two hundred specimens with 7 mm diameter and 3 mm height pre-sintered zirconia blocks were fabricated. Specimens were randomly divided into 10 groups (n=20) according to surface treatments applied. Group C, untreated (Control); Group E, erbium:yttrium-aluminum-garnet (Er:YAG) laser irradiated; Group N, neodymium:yttrium-aluminum-garnet (Nd:YAG) laser irradiated; Group SB, sandblasted; Group L, liner applied; Group NL, Nd:YAG laser irradiated+liner applied; Group EL, Er:YAG laser irradiated+liner applied; Group SN, sandblasted+Nd:YAG laser irradiated; Group SE, sandblasted+Er:YAG laser irradiated; and Group SL, sandblasted+liner applied. The disks were then veneered with veneering porcelain. Before the experiment, specimens were steeped in 37°C distilled water for 24 h. All specimens were thermocycled for 5000 cycles between 5°C and 55°C with a 30 sec dwell time. Shear bond strength test was performed at a crosshead speed of 1 mm/min. The fractured specimens were examined under a stereomicroscope to evaluate the fracture pattern. Surface treatments significantly changing the topography of the yttrium-stabilized tetragonal zirconia (Y-TZP) ceramic according to scanning electron microscopic (SEM) images. The highest mean bond strength value was obtained in Group SE, and the lowest bond strength value was observed in NL group. Bond strength values of the other groups were similar to each other. This

  16. Surface treatment of disk made by ultra-precision diamond turning

    International Nuclear Information System (INIS)

    Higashi, Norio; Higashi, Yasuo; Kudo, Noboru; Higo, Toshiyasu; Besyo, Koutarou; Funahashi, Yoshisato; Nagai, Minoru

    2005-01-01

    The etching treatment is applied to disk surface of X-band accelerator structures before bonding processes such as diffusion bonding and brazing. The KEK etching process was developed by modifying the process given by SLAC, where KEK-made disks are assembled and bonded as one of the collaborating activities between SLAC and KEK. The surface evaluation of the treated disks was performed by SEM (scanning electron microscope) with its magnification of about X500, in addition to the inspection by eye. The information and treatment process specification are described here. (author)

  17. Enhancing wire-composite bond strength of bonded retainers with wire surface treatment.

    Science.gov (United States)

    Oesterle, L J; Shellhart, W C; Henderson, S

    2001-06-01

    Bonded orthodontic retainers with wires embedded in composite resin are commonly used for orthodontic retention. The purpose of this study was to test, in vitro, various wire surface treatments to determine the optimal method of enhancing the wire-composite bond strength. Coaxial wires and stainless steel wires with different surface treatments were bonded to bovine enamel and then pulled along their long axes with an Instron universal testing machine. Wire surface treatments included placing a right-angle bend in the wire, microetching the wire, and treating the wire with adhesion promoters; combinations of treatments were also examined. The results demonstrated a 24-fold increase in the wire-composite bond strength of wire that was microetched (sandblasted), compared with that of untreated straight wire. The difference between the amount of force required to break the bond produced by microetching alone (246.1 +/- 46.0 MPa) and that required for the bonds produced by the retentive bend (87.8 +/- 16.3 MPa), the adhesion promoters (silane, 11.0 +/- 3.1 MPa; Metal Primer, 28.5 +/- 15.8 MPa), or for any combination of surface treatments, was statistically significant. Microetching a stainless steel wire produced a higher wire-composite bond strength than that obtained from a coaxial wire (113.5 +/- 27.5 MPa). The results of this study indicate that microetching or sandblasting a stainless steel wire significantly increases the strength of the wire-composite bond.

  18. Immobilization of epidermal growth factor on titanium and stainless steel surfaces via dopamine treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jeonghwa [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Tokyo, 192-0397 Japan (Japan); Sakuragi, Makoto; Shibata, Aya; Abe, Hiroshi; Kitajima, Takashi; Tada, Seiichi [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Mizutani, Masayoshi; Ohmori, Hitoshi [Material Fabrication Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Ayame, Hirohito [Diagnostic Biochip Laboratory, RIKEN Center for Intellectual Property Strategies, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Son, Tae Il [Bioscience and Biotechnology, Chung-Ang University, 40-1 San, Nae-Ri, Daeduck-myun, Ansung-si, Kyungki-do, 456-756 (Korea, Republic of); Aigaki, Toshiro [Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Tokyo, 192-0397 Japan (Japan); Ito, Yoshihiro, E-mail: y-ito@riken.jp [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Tokyo, 192-0397 Japan (Japan); Diagnostic Biochip Laboratory, RIKEN Center for Intellectual Property Strategies, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan)

    2012-12-01

    Titanium and stainless steel were modified with dopamine for the immobilization of biomolecules, epidermal growth factor (EGF). First, the treatment of metal surfaces with a dopamine solution under different pH conditions was investigated. At higher pH, the dopamine solution turned brown and formed precipitates. Treatment of the metals with dopamine at pH 8.5 also resulted in the development of brown color at the surface of the metals. The hydrophobicity of the surfaces increased after treatment with dopamine, independently of pH. X-ray photoelectron spectroscopy revealed the formation of a significant amount of an organic layer on both surfaces at pH 8.5. According to ellipsometry measurements, the organic layer formed at pH 8.5 was about 1000 times as thick as that formed at pH 4.5. The amount of amino groups in the layer formed at pH 8.5 was also higher than that observed in the layer formed at pH 4.5. EGF molecules were immobilized onto the dopamine-treated surfaces via a coupling reaction using carbodiimide. A greater amount of EGF was immobilized on surfaces treated at pH 8.5 compared with pH 4.5. Significantly higher growth of rat fibroblast cells was observed on the two EGF-immobilized surfaces compared with non-immobilized surfaces in the presence of EGF. The present study demonstrated that metals can become bioactive via the surface immobilization of a growth factor and that the effect of the immobilized growth factor on metals was greater than that of soluble growth factor. - Highlights: Black-Right-Pointing-Pointer Epidermal growth factor was covalently immobilized on titan or stainless steel surfaces. Black-Right-Pointing-Pointer Amino groups were formed on the surfaces by the treatment and the growth factor was immobilized through amide bonds. Black-Right-Pointing-Pointer The immobilized epidermal growth factor accelerated cell proliferation more than soluble ones on the surfaces.

  19. Atmospheric-Pressure Plasma Jet Surface Treatment for Use in Improving Adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Kuettner, Lindsey Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-06

    Atmospheric-pressure plasma jets (APPJs) are a method of plasma treatment that plays an important role in material processing and modifying surface properties of materials, especially polymers. Gas plasmas react with polymer surfaces in numerous ways such as oxidation, radical formation, degradation, and promotion of cross-linking. Because of this, gas and plasma conditions can be explored for chosen processes to maximize desired properties. The purpose of this study is to investigate plasma parameters in order to modify surface properties for improved adhesion between aluminum and epoxy substrates using two types of adhesives. The background, results to date, and future work will be discussed.

  20. A Pulse Power Modulator System for Commercial High Power Ion Beam Surface Treatment Applications

    International Nuclear Information System (INIS)

    Barrett, D.M.; Cockreham, B.D.; Dragt, A.J.; Ives, H.C.; Neau, E.L.; Reed, K.W.; White, F.E.

    1999-01-01

    The Ion Beam Surface Treatment (lBESTrM) process utilizes high energy pulsed ion beams to deposit energy onto the surface of a material allowing near instantaneous melting of the surface layer. The melted layer typically re-solidifies at a very rapid rate which forms a homogeneous, fine- grained structure on the surface of the material resulting in significantly improved surface characteristics. In order to commercialize the IBESTTM process, a reliable and easy-to-operate modulator system has been developed. The QM-I modulator is a thyratron-switched five-stage magnetic pulse compression network which drives a two-stage linear induction adder. The adder provides 400 kV, 150 ns FWHM pulses at a maximum repetition rate of 10 pps for the acceleration of the ion beam. Special emphasis has been placed upon developing the modulator system to be consistent with long-life commercial service

  1. Inactivation of norovirus surrogates on surfaces and raspberries by steam-ultrasound treatment

    DEFF Research Database (Denmark)

    Schultz, Anna Charlotte; Uhrbrand, Katrine; Nørrung, Birgit

    2012-01-01

    Human disease outbreaks caused by norovirus (NoV) following consumption of contaminated raspberries are an increasing problem. An efficient method to decontaminate the fragile raspberries and the equipment used for processing would be an important step in ensuring food safety. A potential surface...... treatment that combines pressurized steam and high-power ultrasound (steam-ultrasound) was assessed for its efficacy to inactivate human NoV surrogates: coliphage (MS2), feline calicivirus (FCV), and murine norovirus (MNV) inoculated on plastic surfaces and MS2 inoculated on fresh raspberries. The amounts......, respectively; while a 3.7-log (99.9%) reduction of MNV was reached after 3 s of treatment. However, on fresh raspberries only a 1-log reduction (∼89%) of MS2 could be achieved after 1 s of treatment, at which point damage to the texture of the fresh raspberries was evident. Increasing treatment time (0 to 3 s...

  2. Surface modification of a natural zeolite by treatment with cold oxygen plasma: Characterization and application in water treatment

    Science.gov (United States)

    De Velasco-Maldonado, Paola S.; Hernández-Montoya, Virginia; Montes-Morán, Miguel A.; Vázquez, Norma Aurea-Rangel; Pérez-Cruz, Ma. Ana

    2018-03-01

    In the present work the possible surface modification of natural zeolite using cold oxygen plasma was studied. The sample with and without treatment was characterized using nitrogen adsorption isotherms at -196 °C, FT-IR spectroscopy, SEM/EDX analysis and X-Ray Diffraction. Additionally, the two samples were used for the removal of lead and acid, basic, reactive and food dyes in batch systems. The natural zeolite was found to be a mesoporous material with a low specific surface area (23 m2/g). X-ray patterns confirmed that clinoptilolite was the main crystal structure present in the natural zeolite. The molecular properties of dyes and the zeolitic structure were studied using molecular simulation, with the purpose to understand the adsorption mechanism. The results pointed out that only the roughness of the clinoptilolite was affected by the plasma treatment, whereas the specific surface area, chemical functionality and crystal structure remained constant. Finally, adsorption results confirmed that the plasma treatment had no significant effects on the dyes and lead retention capacities of the natural zeolite.

  3. The Effect of Plasma Surface Treatment on a Porous Green Ceramic Film with Polymeric Binder Materials

    International Nuclear Information System (INIS)

    Yun Jeong Woo

    2013-01-01

    To reduce time and energy during thermal binder removal in the ceramic process, plasma surface treatment was applied before the lamination process. The adhesion strength in the lamination films was enhanced by oxidative plasma treatment of the porous green ceramic film with polymeric binding materials. The oxygen plasma characteristics were investigated through experimental parameters and weight loss analysis. The experimental results revealed the need for parameter analysis, including gas material, process time, flow rate, and discharge power, and supported a mechanism consisting of competing ablation and deposition processes. The weight loss analysis was conducted for cyclic plasma treatment rather than continuous plasma treatment for the purpose of improving the film's permeability by suppressing deposition of the ablated species. The cyclic plasma treatment improved the permeability compared to the continuous plasma treatment.

  4. Molecular surface structural changes of plasticized PVC materials after plasma treatment.

    Science.gov (United States)

    Zhang, Xiaoxian; Zhang, Chi; Hankett, Jeanne M; Chen, Zhan

    2013-03-26

    In this research, a variety of analytical techniques including sum frequency generation vibrational spectroscopy (SFG), coherent anti-Stokes Raman spectroscopy (CARS), and X-ray photoelectron spectroscopy (XPS) have been employed to investigate the surface and bulk structures of phthalate plasticized poly(vinyl chloride) (PVC) at the molecular level. Two types of phthalate molecules with different chain lengths, diethyl phthalate (DEP) and dibutyl phthalate (DBP), mixed with PVC in various weight ratios were examined to verify their different surface and bulk behaviors. The effects of oxygen and argon plasma treatment on PVC/DBP and PVC/DEP hybrid films were investigated on both the surface and bulk of films using SFG and CARS to evaluate the different plasticizer migration processes. Without plasma treatment, SFG results indicated that more plasticizers segregate to the surface at higher plasticizer bulk concentrations. SFG studies also demonstrated the presence of phthalates on the surface even at very low bulk concentration (5 wt %). Additionally, the results gathered from SFG, CARS, and XPS experiments suggested that the PVC/DEP system was unstable, and DEP molecules could leach out from the PVC under low vacuum after several minutes. In contrast, the PVC/DBP system was more stable; the migration process of DBP out of PVC could be effectively suppressed after oxygen plasma treatment. XPS results indicated the increase of C═O/C-O groups and decrease of C-Cl functionalities on the polymer surface after oxygen plasma treatment. The XPS results also suggested that exposure to argon plasma induced chemical bond breaking and formation of cross-linking or unsaturated groups with chain scission on the surface. Finally, our results indicate the potential risk of using DEP molecules in PVC since DEP can easily leach out from the polymeric bulk.

  5. Effect of Surface Treatment on Performance of Electrode Material Based on Carbon Fiber Cloth

    Directory of Open Access Journals (Sweden)

    XU Jian

    2018-01-01

    Full Text Available The carbon fiber cloth was treated by surface treatment, and then it was used as the electrode substrate. The electrode material based on carbon fibers was synthesized by a galvanostatic electrodeposition method. The interface resistivity, electrochemical property and corrosion resistance of the CF/β-PbO2 electrode were characterized by four-probe method and electrochemical workstation, respectively. The results show that the surface roughness and chemical activity of the carbon fibers can be significantly improved through surface treatment. The carbon fibers possess the best chemical activity on the surface at the hot-air oxidation temperature of 400℃. Joint hot-air and liquid-phase oxidations show that the chemical activity of the carbon fibers on the surface is further improved, the grooves and pits on the surface of the carbon fibers are more obvious, after this treatment, the interface resistivity of the CF/β-PbO2 electrode reaches the minimum value of 6.19×10-5Ω·m, meanwhile, the conductivity and the electrochemical property of the CF/β-PbO2 electrode reaches the best, and with the best corrosion resistance, the corrosion rate is only 1.44×10-3g·cm-2·h-1.Thus, the interface resistivity, electrochemical property and corrosion resistance of the CF/β-PbO2 electrode depend on the the interface structure of the CF/β-PbO2 electrode obtained under different surface treatments.

  6. Effects of surface treatment on bond strength between dental resin agent and zirconia ceramic.

    Science.gov (United States)

    Moradabadi, Ashkan; Roudsari, Sareh Esmaeily Sabet; Yekta, Bijan Eftekhari; Rahbar, Nima

    2014-01-01

    This paper presents the results of an experimental study to understand the dominant mechanism in bond strength between dental resin agent and zirconia ceramic by investigating the effects of different surface treatments. Effects of two major mechanisms of chemical and micromechanical adhesion were evaluated on bond strength of zirconia to luting agent. Specimens of yttrium-oxide-partially-stabilized zirconia blocks were fabricated. Seven groups of specimens with different surface treatment were prepared. 1) zirconia specimens after airborne particle abrasion (SZ), 2) zirconia specimens after etching (ZH), 3) zirconia specimens after airborne particle abrasion and simultaneous etching (HSZ), 4) zirconia specimens coated with a layer of a Fluorapatite-Leucite glaze (GZ), 5) GZ specimens with additional acid etching (HGZ), 6) zirconia specimens coated with a layer of salt glaze (SGZ) and 7) SGZ specimens after etching with 2% HCl (HSGZ). Composite cylinders were bonded to airborne-particle-abraded surfaces of ZirkonZahn specimens with Panavia F2 resin luting agent. Failure modes were examined under 30× magnification and the effect of surface treatments was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). SZ and HSZ groups had the highest and GZ and SGZ groups had the lowest mean shear bond strengths among all groups. Mean shear bond strengths were significantly decreased by applying a glaze layer on zirconia surfaces in GZ and SGZ groups. However, bond strengths were improved after etching process. Airborne particle abrasion resulted in higher shear bond strengths compared to etching treatment. Modes of failure varied among different groups. Finally, it is concluded that micromechanical adhesion was a more effective mechanism than chemical adhesion and airborne particle abrasion significantly increased mean shear bond strengths compared with another surface treatments. © 2013.

  7. Effect of resin and type of surface treatment on the flexural strength of cracked feldspathic porcelain

    Directory of Open Access Journals (Sweden)

    Kermanshah Hamid

    2015-05-01

    Full Text Available Background and Aims: Porcelain restorations are often ground for clinical adjustment and this removes the surface glaze layer and introduces flaws that can grow in wet environments due to stress-corrosion, reduce the strength of porcelain and limit restoration lifetime. The aim of this study was to introduce some surface treatment methods to control the flaws of ceramic restorations external surface and improve their strength.   Materials and Methods: 40 feldspathic discs were prepared and divided into 4 groups (n=10: not indented (group 1 and others indented by vickers with 29.4 N and received different treatments: no treatment (group 2, polished (group 3 and polished-silane-resin (group 4. Biaxial flexural strength of discs was tested after water storage. Data were analyzed using one-way ANOVA .   Results: The mean flexural strength of specimens in group 1 (134.49±12.60, 2 (94.81±15.41, 3 (89.20±16.22 and 4 (80.67±12.01 were measured. Group 1 (not indented revealed significantly higher strength (P<0.001 than that of indented groups (2, 3 and 4 . There was no significant difference between group 2 (no treatment and 3 or 4 (treated and between treatment methods (3 and 4 (P=0.136.   Conclusion: The strength of porcelains is dependent on presence of cracks. With the limitations of this study, none of the treatment methods could strengthen the cracked ceramic.

  8. Surface properties and water treatment capacity of surface engineered silica coated with 3-(2-aminoethyl) aminopropyltrimethoxysilane

    Energy Technology Data Exchange (ETDEWEB)

    Majewski, Peter, E-mail: peter.majewski@unisa.edu.au [School of Advanced Manufacturing and Mechanical Engineering, Mawson Institute, University of South Australia, Adelaide (Australia); Keegan, Alexandra [Microbiology Research, Australian Water Quality Centre, South Australian Water Corporation, Adelaide (Australia)

    2012-01-15

    This study's focus was on the water-based, one-pot preparation and characterisation of silica particles coated with 3-(2-aminoethyl)aminopropyltrimethoxysilane (Diamo) and the efficiency of the material in removing the pathogens Escherichia coli, Pseudomonas aeruginosa, Mycobacterium immunogenum, Vibrio cholerae, poliovirus, and Cryptosporidium parvum. The water-based processing resulted in Diamo coated silica particles with significantly increased positive surface charge as determined by zeta potential measurements. In addition, X-ray photoelectron spectrometry of pure and Diamo coated silica confirmed the presence of Diamo on the surface of the particles. Thermogravimetric measurements and chemical analysis of the silica indicated a surface concentration of amine groups of about 1 mmol/g{sub silica}. Water treatment tests with the pathogens showed that a dose of about 10 g appeared to be sufficient to remove pathogens from pure water samples which were spiked with pathogen concentrations between about 10{sup 2} and 10{sup 4} cfu/mL.

  9. Surface dose in the treatment of breast cancer with helical tomotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Zibold, Felix; Sterzing, Florian; Sroka-Perez, Gabriele; Schubert, Kai; Wagenknecht, Katja; Major, Gerald; Debus, Juergen; Herfarth, Klaus [Dept. of Radiation Oncology, Univ. of Heidelberg (Germany)

    2009-09-15

    Purpose: investigation of the effects of breathing motion- and misregistration-induced errors on the superficial dose in the treatment of breast cancer using helical tomotherapy (HT). Material and methods: surface dose measurements were performed with thermoluminescence dosimetry (TLD). Two treatment plans with different planning target volume (PTV) definitions of the left breast were used: PTV{sub skin} had its ventral border exactly on skin level, while PTV{sub air} included also a 10-mm extension ventral to the PTV{sub skin}. With a thoracic static phantom, misregistration errors in an HT were simulated. A dynamic phantom was used to simulate a breathing patient during HT. Surface doses of breast cancer patients were measured both for an HT (179 points) and a conventional three-dimensional conformal treatment (70 points). Results: in the static phantom misregistration setup, dose deviations of -31.9% for PTV{sub skin} to +35.4% for PTV{sub air} could be observed. The dynamic phantom measurements resulted in surface dose deviations from those in a static position between 0.8% and 3.8% without a significant difference for the PTV definitions. The measured surface doses on patients averaged (mean {+-} standard deviation) 1.65 {+-} 0.13 Gy for the HT and 1.42 {+-} 0.11 Gy for the three-dimensional conformal treatment. Conclusion: HT enables a homogeneous and reproducible surface dose with small dose deviations in the treatment of breast cancer. HT is a feasible method to treat breast cancer under free shallow breathing of the patient using a treatment plan with a ventral PTV border on the skin level. (orig.)

  10. Improvement of organic solar cells by flexible substrate and ITO surface treatments

    International Nuclear Information System (INIS)

    Cheng, Yuang-Tung; Ho, Jyh-Jier; Wang, Chien-Kun; Lee, William; Lu, Chih-Chiang; Yau, Bao-Shun; Nain, Jhen-Liang; Chang, Shun-Hsyung; Chang, Chiu-Cheng; Wang, Kang L.

    2010-01-01

    In this paper, surface treatments on polyethylene terephthalate with polymeric hard coating (PET-HC) substrates are described. The effect of the contact angle on the treatment is first investigated. It has been observed that detergent is quite effective in removing organic contamination on the flexible PET-HC substrates. Next, using a DC-reactive magnetron sputter, indium tin oxide (ITO) thin films of 90 nm are grown on a substrate treated by detergent. Then, various ITO surface treatments are made for improving the performance of the finally developed organic solar cells with structure Al/P3HT:PCBM/PEDOT:PSS/ITO/PET. It is found that the parameters of the ITO including resistivity, carrier concentration, transmittance, surface morphology, and work function depended on the surface treatments and significantly influence the solar cell performance. With the optimal conditions for detergent treatment on flexible PET substrates, the ITO film with a resistivity of 5.6 x 10 -4 Ω cm and average optical transmittance of 84.1% in the visible region are obtained. The optimal ITO surface treated by detergent for 5 min and then by UV ozone for 20 min exhibits the best WF value of 5.22 eV. This improves about 8.30% in the WF compared with that of the untreated ITO film. In the case of optimal treatment with the organic photovoltaic device, meanwhile, 36.6% enhancement in short circuit current density (J sc ) and 92.7% enhancement in conversion efficiency (η) over the untreated solar cell are obtained.

  11. Relations among pH, sulfate, and metals concentrations in anthracite and bituminous coal-mine discharges, Pennsylvania

    Science.gov (United States)

    Cravotta, III, Charles A.

    2006-01-01

    Water-quality data for discharges from 140 abandoned mines in the Bituminous and Anthracite Coalfields of Pennsylvania illustrate relations among pH, sulfate, and dissolved metal concentrations. The pH for the 140 samples ranged from 2.7 to 7.3, with two modes at pH 2.5 to 4 (acidic) and 6 to 7 (near neutral). Generally, flow rates were smaller and solute concentrations were greater for low-pH samples; flow rates increased with pH. Although the pH distribution was similar for the bituminous and anthracite subsets, the bituminous discharges had smaller median flow rates, greater concentrations of sulfate, iron, and aluminum, and smaller concentrations of barium and lead than anthracite discharges with the same pH values. The observed relations between the pH and constituent concentrations can be attributed to (1) dilution of acidic water by alkaline ground water; (2) solubility control of aluminum, iron, manganese, barium, and lead by hydroxide, sulfate, and/or carbonate minerals; and (3) aqueous sulfate-complex formation. The formation of AlSO4+ and AlHSO4+2 complexes adds to the total dissolved aluminum concentration at pH of equilibrium with aluminum hydroxide or hydroxysulfate minerals and can account for 10 to 20 times greater concentrations of dissolved aluminum in bituminous discharges compared to anthracite discharges at similar pH. Sulfate complexation also can account for 10 to 30 times greater concentrations of dissolved ferric iron concentrations at equilibrium with ferrihydrite (Fe(OH)3) and/or schwertmannite (Fe8O8(OH)4.5(SO4)1.75) at pH of 3 to 5. In contrast, lower barium and lead concentrations in bituminous than anthracite discharges indicates elevated sulfate concentration could decrease mobility of these metals by the formation of insoluble minerals such as barite (BaSO4) or anglesite (PbSO4). Most samples were saturated with barite, but none were saturated with anglesite. Hence, lead concentrations could be controlled by coprecipitation with

  12. Effect of heat treatment on carbon fiber surface properties and fibers/epoxy interfacial adhesion

    International Nuclear Information System (INIS)

    Dai Zhishuang; Zhang Baoyan; Shi Fenghui; Li Min; Zhang Zuoguang; Gu Yizhuo

    2011-01-01

    Carbon fiber surface properties are likely to change during the molding process of carbon fiber reinforced matrix composite, and these changes could affect the infiltration and adhesion between carbon fiber and resin. T300B fiber was heat treated referring to the curing process of high-performance carbon fiber reinforced epoxy matrix composites. By means of X-ray photoelectron spectroscopy (XPS), activated carbon atoms can be detected, which are defined as the carbon atoms conjunction with oxygen and nitrogen. Surface chemistry analysis shows that the content of activated carbon atoms on treated carbon fiber surface, especially those connect with the hydroxyl decreases with the increasing heat treatment temperature. Inverse gas chromatography (IGC) analysis reveals that the dispersive surface energy γ S d increases and the polar surface energy γ S sp decreases as the heat treatment temperature increases to 200. Contact angle between carbon fiber and epoxy E51 resin, which is studied by dynamic contact angle test (DCAT) increases with the increasing heat treatment temperature, indicating the worse wettability comparing with the untreated fiber. Moreover, micro-droplet test shows that the interfacial shear strength (IFSS) of the treated carbon fiber/epoxy is lower than that of the untreated T300B fiber which is attributed to the decrement of the content of reactive functional groups including hydrogen group and epoxy group.

  13. Effect from surface treatment of nickel-titanium rotary files on the fracture resistance.

    Science.gov (United States)

    Kim, Bo Hoon; Ha, Jung-Hong; Lee, Woo Cheol; Kwak, Sang-Won; Kim, Hyeon-Cheol

    2015-01-01

    This study was aimed to compare the cyclic fatigue resistance and torsional resistance of rotary instruments with and without surface treatment. G6 A2 (Group A2) with and G6 A2 without surface treatment after machining (Group AN) were compared in this study. ProTaper F2 (Group F2) which has similar dimension and shape was also used for comparison. To evaluate the torsional resistance, ultimate torsional strength and distortion angle until fracture were recorded, and the toughness was calculated. The cyclic fatigue resistance was compared by evaluating the number of cycles to failure in a simulated canal. Statistical analysis was performed by one-way analysis of variance and Tukey post hoc test (p = 0.05). After torsional and cyclic fatigue tests, all fracture fragments were observed under a scanning electron microscope. Group A2 showed higher cyclic fatigue resistance than the groups AN and F2 (p machining grooves were seen in groups AN and F2, group A2 showed smooth surface resulting from the surface treatment. The specimens of fracture fragments showed typical features of cyclic failure such as micro-cracks, overloaded fast fracture zone, and torsional fracture such as unwinding helix, circular abrasion marks and dimples. Under the conditions of this study, the surface treated instruments may improve cyclic fatigue resistance while maintaining the torsional resistances and mechanical properties. © Wiley Periodicals, Inc.

  14. Surface chemistry of polyacrylonitrile- and rayon-based activated carbon fibers after post-heat treatment

    International Nuclear Information System (INIS)

    Chiang Yuchun; Lee, C.-Y.; Lee, H.-C.

    2007-01-01

    Polyacrylonitrile- and rayon-based activated carbon fibers (ACFs) subject to heat treatment were investigated by means of elemental analyzer, and X-ray photoelectron spectroscopy (XPS). The total ash content of all ACFs was also analyzed. The adsorption of benzene, carbon tetrachloride and water vapor on ACFs was determined to shed light on the role of surface chemistry on gas adsorption. Results show that different precursors resulted in various elemental compositions and imposed diverse influence upon surface functionalities after heat treatment. The surface of heat-treated ACFs became more graphitic and hydrophobic. Three distinct peaks due to C, N, and O atoms were identified by XPS, and the high-resolution revealed the existence of several surface functionalities. The presence of nitride-like species, aromatic N-imines, or chemisorbed nitrogen oxides was found to be of great advantage to adsorption of water vapor or benzene, but the pyridine-N was not. Unstable complexes on the surface would hinder the fibers from adsorption of carbon tetrachloride. The rise in total ash content or hydrogen composition was of benefit to the access of water vapor. Modifications of ACFs by heat treatment have effectively improved adsorption performance

  15. Surface treatment in a cathodic arc plasma. Key step for interface engineering

    International Nuclear Information System (INIS)

    Schoenjahn, C.

    2001-02-01

    The effect of substrate surface treatment (substrate sputter cleaning) in a cathodic arc plasma prior to unbalanced magnetron deposition of transition metal nitride coatings on the performance of the coated components has been investigated. In particular the influence of parameters such as ion species, ion energy and exposure time on the changes in substrate surface topography, microstructure and microchemistry were studied employing transmission electron microscopy, energy dispersive X-ray analysis, electron energy loss spectroscopy, X-ray diffraction, atomic force microscopy and optical microscopy. The consequences for both the microstructure of subsequently grown transition metal nitride coatings and their adhesion were elucidated. The relevance for practical applications was demonstrated using the example of dry high-speed milling tests, which showed that an appropriate choice of substrate surface pre-treatment parameters can double the life time of the coated tools. This was found to be due to an improved adhesion as a result of a combination of reduced oxygen incorporation at the interface between coating and substrate and local epitaxial growth of the coating. The latter is promoted by certain substrate surface pre-treatment procedures, which provide clean surfaces with preserved crystallographic order. (author)

  16. Investigation of surface treatment of conductive wire in cylindrical atmospheric pressure plasmas

    International Nuclear Information System (INIS)

    Ye Rubin; Kagohashi, Tsutomu; Zheng Wei

    2009-01-01

    Polyethylene insulated electric wire was treated in He and Ar dielectric barrier discharge atmospheric pressure plasmas generated in a quartz tube wound with tubular electrodes. The wire was put penetrating through the high voltage and the grounded electrodes, improving the discharge and facilitating uniform surface treatment. In this work, the influences of conductivity of the wire on the effects of surface treatment and discharge behavior were investigated. Surface properties of the wire samples were analyzed by means of surface energy measurement and X-ray photoelectron spectroscopy. In order to reveal the mechanism for treating the conductive wire, I-V discharge waveforms were measured and time-resolved plasma images were taken. It was demonstrated that the conductive wire was involved in the discharge process, reducing the breakdown voltage significantly and enhancing the discharge. It shows that the discharge mode was strongly dependent on the conductivity of a wire. Intensive surface discharges developed along the conductive wire were found to be mainly responsible for noticeable improvement in the treatment effect.

  17. Tensile bond strength of composite luting cements to metal alloys after various surface treatments

    Directory of Open Access Journals (Sweden)

    Denizoglu Saip

    2009-01-01

    Full Text Available Aims: To evaluate the effects of two different surface treatments and bonding agents on tensile bond strength between a Co-Cr and a Ni-Cr cast alloy and two resin-luting cements. Materials and Methods: Two hundred and forty alloy samples were cast and subjected to surface treatments such as sandblasting, chemical etching, and sandblasting plus chemical etching. Panavia F and CandB cement were used as cementing mediums. The etching qualities were examined by a stereooptic microscope. Failure surfaces were examined throughout scanning electron microscopy. The data were evaluated using statistical methods, namely analysis of variance and multiple comparison test (Tukey HSD. Results: Significant differences were found in the bonding provided by the various cements (P < 0.001 and also type of surface treatments (P < 0.001. For all groups, sandblasted surfaces showed the highest bond strength values. There was no significant difference between the Cr-Co and the Cr-Ni alloys (P > 0.05. Conclusions: Panavia F showed higher tensile strength and the sandblasted samples possessed higher tensile strength.

  18. Plasma surface treatment to improve surface charge accumulation and dissipation of epoxy resin exposed to DC and nanosecond-pulse voltages

    Science.gov (United States)

    Zhang, Cheng; Lin, Haofan; Zhang, Shuai; Xie, Qin; Ren, Chengyan; Shao, Tao

    2017-10-01

    In this paper, deposition by non-thermal plasma is used as a surface modification technique to change the surface characteristics of epoxy resin exposed to DC and nanosecond-pulse voltages. The corresponding surface characteristics in both cases of DC and nanosecond-pulse voltages before and after the modification are compared and investigated. The measurement of the surface potential provides the surface charge distribution, which is used to show the accumulation and dissipation process of the surface charges. Morphology observations, chemical composition and electrical parameters measurements are used to evaluate the treatment effects. The experimental results show that, before the plasma treatment, the accumulated surface charges in the case of the DC voltage are more than that in the case of the nanosecond-pulse voltage. Moreover, the decay rate of the surface charges for the DC voltage is higher than that for the nanosecond-pulse voltage. However, the decay rate is no more than 41% after 1800 s for both types of voltages. After the plasma treatment, the maximum surface potentials decrease to 57.33% and 32.57% of their values before treatment for the DC and nanosecond-pulse voltages, respectively, indicating a decrease in the accumulated surface charges. The decay rate exceeds 90% for both types of voltages. These changes are mainly attributed to a change in the surface nanostructure, an increase in conductivity, and a decrease in the depth of energy level.

  19. Plasma surface treatment to improve surface charge accumulation and dissipation of epoxy resin exposed to DC and nanosecond-pulse voltages

    International Nuclear Information System (INIS)

    Zhang, Cheng; Lin, Haofan; Zhang, Shuai; Ren, Chengyan; Shao, Tao; Xie, Qin

    2017-01-01

    In this paper, deposition by non-thermal plasma is used as a surface modification technique to change the surface characteristics of epoxy resin exposed to DC and nanosecond-pulse voltages. The corresponding surface characteristics in both cases of DC and nanosecond-pulse voltages before and after the modification are compared and investigated. The measurement of the surface potential provides the surface charge distribution, which is used to show the accumulation and dissipation process of the surface charges. Morphology observations, chemical composition and electrical parameters measurements are used to evaluate the treatment effects. The experimental results show that, before the plasma treatment, the accumulated surface charges in the case of the DC voltage are more than that in the case of the nanosecond-pulse voltage. Moreover, the decay rate of the surface charges for the DC voltage is higher than that for the nanosecond-pulse voltage. However, the decay rate is no more than 41% after 1800 s for both types of voltages. After the plasma treatment, the maximum surface potentials decrease to 57.33% and 32.57% of their values before treatment for the DC and nanosecond-pulse voltages, respectively, indicating a decrease in the accumulated surface charges. The decay rate exceeds 90% for both types of voltages. These changes are mainly attributed to a change in the surface nanostructure, an increase in conductivity, and a decrease in the depth of energy level. (paper)

  20. Contribution to physico-chemical study of Timahdit bituminous schists (Morocco): Organic matters and metalloporphyrins

    International Nuclear Information System (INIS)

    Saoiabi, A.

    1982-01-01

    The Timahdit bituminous schists have been analysed by different methods. The experimental results obtained using these methods concern the behaviour of the schists and the Kerogen facing the pyrolysis, as well as the separation of the hydrocarbons and the metalloporphyrins. For this purpose the techniques used are: 'Rock Eval' pyrolysis, thermogravimetric analysis and electron paramagnetic resonance (E.P.R.) for the raw rock and the Kerogen; infrared (I.R.), gas chromatography and E.P.R. for the extracted organic matters; E.P.R., I.R., nuclear magnetic resonance (N.M.R.), ultraviolet (U.V.) and mass spectrometry for the metalloporphyrins identification and characterization. The analysis of these schists has shown that: We can extract per solvent only 1% of organic matters, ferric oxide hasn't any effect neither on the pyrolysis nor on the organic matters extraction and that the Kerogen of these schists are relatively rich in hydrocarbonic compounds. The gas chromatography reveal the presence of alkanes with odd number of carbons and isoprenoids. All these criteria indicate an immature, little developped organic matter which having probably a marine origin but possessing a good oil potential. It has also been observed that a part of Iron, Nickel and Vanadium in the schists are incorporated into the organic matters. Nickel and Vanadium are into macrocycles which are porphyrins. A method for extracting and separating these porphyrins has been developped. 43 figs., 21 tabs., 58 refs. (author)

  1. Highly crystalline Zeolite-A from flyash of bituminous and lignite coal combustion.

    Science.gov (United States)

    Rayalu, S S; Udhoji, J S; Munshi, K N; Hasan, M Z

    2001-11-16

    Flyash is being generated in voluminous amounts by large scale coal combustion process. It poses a serious threat to thermal power industries specifically, in India, wherein the percent of utilisation of flyash is very poor (3-5%). In view of this problem, newer methods of its disposal and utilisation are being explored. The synthesis of zeolite from flyash appears to be one of the most promising alternatives as it has emphasis on value addition to waste material. Flyashes originating from different sources of coal differ in their characteristics and have implications in this work on Zeolite-A production. These factors have been thoroughly investigated and the conditions favourable for formation of Zeolite-A have been delineated. The reactivity of flyash towards zeolite formation is directly dependent on the SiO(2)/Al(2)O(3) ratio, Fe(2)O(3) and CaO content. Amongst the flyashes investigated, so far the sub-bituminous coal based flyash with SiO(2)/Al(2)O(3) ratio of 3.47 appears to be a suitable substrate for Zeolite-A synthesis. These zeolites have been characterised with respect to XRD crystallinity, calcium binding capacity (CBC) and sorption capacity, wherein the crystallinity ranges from 50 to 100%, the CBC ranges from 290 to 560meq/100g and sorption capacity ranges from 16.6 to 23.8%.

  2. Note on the chemical composition of the asphalts of bituminous coal hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Boente, L.

    1942-10-13

    This report was written not as a result of extensive unified experiments, but as a result of collected observations during the course of various investigations. It interpreted two of the major groups of constituents of the asphalts from hydrogenation of bituminous coal as the following: (1) highly condensed aromatics (including heterocyclic compounds with oxygen, nitrogen, or sulfur in the rings) (a) in dehydrogenated form, or (b) in partially hydrogenated form, and (2) reaction products from labile, partially hydrogenated highly condensed aromatics (a) through oxidation reactions, or (b) through condensation and polymerization reactions. These types of compounds seemed to come from rather symmetric precursors that were not split during pressure hydrogenation, as were most constituents of coal, but were dehydrogenated instead. The types of compounds mentioned above shared several properties with the asphalts, including precipitation and adsorption properties. Some examples given of Group 1 compounds were coronene and several derived from it, as well as napthoxanthene, carbazole, and diphenylene sulfide. One example given to illustrate Group 2 was some hypothetical reactions of a proposed hexakeideca-hydrocoronene.

  3. Co-gasification of bituminous coal and hydrochar derived from municipal solid waste: Reactivity and synergy.

    Science.gov (United States)

    Wei, Juntao; Guo, Qinghua; He, Qing; Ding, Lu; Yoshikawa, Kunio; Yu, Guangsuo

    2017-09-01

    In this work, the influences of gasification temperature and blended ratio on co-gasification reactivity and synergy of Shenfu bituminous coal (SF) and municipal solid waste-derived hydrochar (HTC) were investigated using TGA. Additionally, active alkaline and alkaline earth metal (AAEM) transformation during co-gasification was quantitatively analyzed by inductively coupled plasma optical emission spectrometer for correlating synergy on co-gasification reactivity. The results showed that higher char gasification reactivity existed at higher HTC char proportion and gasification temperature, and the main synergy behaviour on co-gasification reactivity was performed as synergistic effect. Enhanced synergistic effect at lower temperature was mainly resulted from more obviously inhibiting the primary AAEM (i.e. active Ca) transformation, and weak synergistic effect still existed at higher temperature since more active K with prominent catalysis was retained. Furthermore, more active HTC-derived AAEM remaining in SF sample during co-gasification would lead to enhanced synergistic effect as HTC char proportion increased. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Recycling of polyethylene terephthalate (PET plastic bottle wastes in bituminous asphaltic concrete

    Directory of Open Access Journals (Sweden)

    Adebayo Olatunbosun Sojobi

    2016-12-01

    Full Text Available This research sheds light on the concept of eco-friendly road construction which comprises eco-design, eco-extraction, eco-manufacturing, eco-construction, eco-rehabilitation, eco-maintenance, eco-demolition, and socioeconomic empowerment. It also revealed the challenges being faced in its adoption and the benefits derivable from its application. Furthermore, the effects of recycling PET plastic bottle wastes produced in North Central Nigeria in bituminous asphaltic concrete (BAC used in flexible pavement construction were also evaluated. The mix design consists of 60/70 penetration-grade asphaltic concrete (5%, 68% coarse aggregate, 6% fine aggregate, and 21% filler using the dry process at 170°C. The optimum bitumen content (OBC for conventional BAC was obtained as 4% by weight of total aggregates and filler. Polymer-coated aggregate (PCA-modified BAC seems preferable because it has the potential to utilize more plastic wastes with a higher optimum plastic content (OPC of 16.7% by weight of total aggregates and filler compared to that of 9% by weight of OBC achieved by PMB-BAC. For both PMB- and PCA-modified BAC, an increase in air void, void in mineral aggregate, and Marshall stability were observed. Eco-friendly road construction which recycles PET wastes should be encouraged by government considering its potential environmental and economic benefits.

  5. Relation Between Bitumen Content and Percentage Air Voids in Semi Dense Bituminous Concrete

    Science.gov (United States)

    Panda, R. P.; Das, Sudhanshu Sekhar; Sahoo, P. K.

    2018-02-01

    Hot mix asphalt (HMA) is a heterogeneous mix of aggregate, mineral filler, bitumen, additives and air voids. Researchers have indicated that the durability of the HMA is sensitive on the actual bitumen content and percentage air void. This paper aims at establishing the relationship between the bitumen content and the percentage air voids in Semi Dense Bituminous Concrete (SDBC) using Viscosity Grade-30 (VG-30) bitumen. Total 54 samples have been collected, for formulation and validation of relationship and observed that the percentage air voids increases with decrease in actual bitumen content and vice versa. A minor increase in percentage air voids beyond practice of designed air voids in Marshall Method of design is required for better performance, indicating a need for reducing the codal provision of minimum bitumen content for SDBC as specified in Specification for Road & Bridges (Fourth Revision) published by Indian Road Congress, 2001. The study shows a possibility of reducing designed minimum bitumen content from codal provision for SDBC by 0.2% of weight with VG-30 grade of Bitumen.

  6. Using proximate analysis to characterize airborne dust generation from bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Page, S.J.; Organiscak, J.A.

    2005-11-01

    Prolonged exposure to airborne respirable coal dust is responsible for coal workers pneumoconiosis (CWP), commonly called black lung. Health research studies have identified that the prevalence and severity of CWP are directly related to both the amount of dust exposure and the coal rank. The amount of airborne respirable dust (ARD) smaller than 10 micrometers generated from breakage of different coals varies widely. To investigate the cause, researchers for the National Institute for Occupational Safety and Health (NIOSH) have conducted experiments to identify the causes of airborne respirable dust liberation. Laboratory crushing experiments were conducted on a range of low to high volatile bituminous coals from eight mines. The results indicate that the proximate analysis of a coal sample can provide a very good indicator of the potential for a dust problem. For application to the coal mining, processing, and utilization industries, data from 977 US coal seams compiled by the Department of Energy (DoE) has been used to calculate this dust generation potential from an equation based on the NIOSH measured data. A simple procedure for this calculation is provided. 1 fig.

  7. Elemental analysis of Indonesian and Australian bituminous coal used at Kapar Power Station

    International Nuclear Information System (INIS)

    Muneer Saleh; Ahmad Suhaimi

    2008-01-01

    An instrumental neutron activation analytical (INAA) technique is used for the determination of thirty elements in five coal samples collected from Kapar power station, imported from Indonesia and Australia. Analyses of the samples are being associated with standards. All irradiation were performed in the nuclear reactor of Malaysia Nuclear Agency (MNA). samples were counted by Hyper Pure Germanium (HPGe) detector for short period irradiations at MNA, while for the long period irradiations the samples were counted at Universiti Kebangsaan Malaysia (UKM). The concentrations of thirty elements have been determined: The major components are Cl, Ca, Mg, K, Fe, Ti, and Na with the mean concentrations in the range between 70±69 ppm-6100±1639 ppm; and the trace elements are Zr, V, Mn, Sc, Cr, Co, As, Br, Rb, Sb, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Hf, Th, U and Ta with the mean concentrations in the range between 0.1381±0.0202 - 69.0±2.8 ppm. The results have been compared to the reported data of eight coal samples from the United States and the reported data of Australian bituminous coal. (Author)

  8. Curve identification for high friction surface treatment (HFST) installation recommendation : final report.

    Science.gov (United States)

    2016-09-01

    The objectives of this study are to develop and deploy a means for cost-effectively extracting curve information using the widely available GPS and GIS data to support high friction surface treatment (HFST) installation recommendations (i.e., start a...

  9. Effects of different surface treatments on bond strength of an indirect composite to bovine dentin

    Directory of Open Access Journals (Sweden)

    Laiza Tatiana Poskus

    2015-01-01

    Conclusions: Sandblasting was a safe surface treatment for the indirect composite, increasing the BS values. Hydrofluoric acid applied after sandblasting damaged the BS values and should not be recommended while ethanol and H2O2, when applied after sandblasting, were effective in increasing BS values.

  10. Mechanical polishing as an improved surface treatment for platinum screen-printed electrodes

    Directory of Open Access Journals (Sweden)

    Junqiao Lee

    2016-07-01

    Full Text Available The viability of mechanical polishing as a surface pre-treatment method for commercially available platinum screen-printed electrodes (SPEs was investigated and compared to a range of other pre-treatment methods (UV-Ozone treatment, soaking in N,N-dimethylformamide, soaking and anodizing in aqueous NaOH solution, and ultrasonication in tetrahydrofuran. Conventional electrochemical activation of platinum SPEs in 0.5 M H2SO4 solution was ineffective for the removal of contaminants found to be passivating the screen-printed surfaces. However, mechanical polishing showed a significant improvement in hydrogen adsorption and in electrochemically active surface areas (probed by two different redox couples due to the effective removal of surface contaminants. Results are also presented that suggest that SPEs are highly susceptible to degradation by strong acidic or caustic solutions, and could potentially lead to instability in long-term applications due to continual etching of the binding materials. The ability of SPEs to be polished effectively extends the reusability of these traditionally “single-use” devices. Keywords: Screen-printed electrodes, Polishing, Platinum, Activation, Pre-treatment, Cyclic voltammetry

  11. Effect of surface treatment of titanium posts on the tensile bond strength

    NARCIS (Netherlands)

    Schmage, P; Sohn, J; Ozcan, M; Nergiz, [No Value

    Objectives. Retention of composite resins to metal can be improved when metal surfaces are conditioned. The purpose of this investigation was to investigate the effect of two conditioning treatments on the tensile bond strength of four resin-based luting cements and zinc phosphate cement to titanium

  12. Influence of different surface treatments on push‑out bond strengths ...

    African Journals Online (AJOL)

    2015-06-26

    Jun 26, 2015 ... Despite all these advantages, fiber posts have several disadvantages. Debonding is one problem that causes. Influence of different surface treatments on push‑out bond strengths of fiber‑reinforced posts luted with dual‑cure resin cement ... of ceramics and metals for improved adhesion and bonding.

  13. Structure fragmentation of a surface layer of commercial purity titanium during ultrasonic impact treatment

    International Nuclear Information System (INIS)

    Kozelskaya, Anna; Kazachenok, Marina; Sinyakova, Elena; Pochivalov, Yurii; Perevalova, Olga; Panin, Alexey; Hairullin, Rustam

    2015-01-01

    The mechanisms of surface layer fragmentation of titanium specimens subjected to ultrasonic impact treatment is investigated by atomic force microscopy, transmission electron microscopy and electron backscatter diffraction. It is shown that the twin boundaries Σ7b and Σ11b are unable to be strong obstacles for propagation of dislocations and other twins

  14. Surface heparin treatment of the decellularized porcine heart valve : Effect on tissue calcification

    NARCIS (Netherlands)

    Yang, Min; Lin, Yang-Hua; Shi, Wei-Ping; Shi, Hong-Can; Gu, Y. John; Shu, Yu-Sheng

    Tissue calcification is a major cause of failure of bioprosthetic heart valves. Aim of this study was to examine whether surface heparin treatment of the decellularized porcine heart valve reduces tissue calcification. Fresh porcine aortic heart valves were dissected as tissue discs and divided into

  15. Evaluation of push-out bond strength of surface treatments of two esthetic posts

    Directory of Open Access Journals (Sweden)

    Cherif Adel Mohsen

    2012-01-01

    Conclusions: Glass fiber posts recorded higher bond strength than glass ceramic post to both root canal and resin core. Surface treatments increase bond strength for glass fiber and zirconia ceramic posts to both root canal and resin core. SB+SIC+SC gave higher bond strength than E+SC. Bond strength at the cervical section is higher than at the apical section.

  16. Surface properties tuning of welding electrode-deposited hardfacings by laser heat treatment

    Science.gov (United States)

    Oláh, Arthur; Croitoru, Catalin; Tierean, Mircea Horia

    2018-04-01

    In this paper, several Cr-Mn-rich hardfacings have been open-arc deposited on S275JR carbon quality structural steel and further submitted to laser treatment at different powers. An overall increase with 34-98% in the average microhardness and wear resistance of the coatings has been obtained, due to the formation of martensite, silicides, as well as simple and complex carbides on the surface of the hardfacings, in comparison with the reference, not submitted to laser thermal treatment. Surface laser treatment of electrode-deposited hardfacings improves their chemical resistance under corrosive saline environments, as determined by the 43% lower amount of leached iron and respectively, 28% lower amount of manganese ions leached in a 10% wt. NaCl aqueous solution, comparing with the reference hardfacings. Laser heat treatment also promotes better compatibility of the hardfacings with water-based paints and oil-based paints and primers, through the relative increasing in the polar component of the surface energy (with up to 65%) which aids both water and filler spreading on the metallic surface.

  17. Analysis of Porous Structure Parameters of Biomass Chars Versus Bituminous Coal and Lignite Carbonized at High Pressure and Temperature—A Chemometric Study

    Directory of Open Access Journals (Sweden)

    Adam Smoliński

    2017-09-01

    Full Text Available The characteristics of the porous structure of carbonized materials affect their physical properties, such as density or strength, their sorption capacity, and their reactivity in thermochemical processing, determining both their applicability as fuels or sorbents and their efficiency in various processes. The porous structure of chars is shaped by the combined effects of physical and chemical properties of a carbonaceous material and the operating parameters applied in the carbonization process. In the study presented, the experimental dataset covering parameters of various fuels, ranging from biomass through lignite to bituminous coal, and chars produced at 1273 K and under the pressure of 1, 2, 3, and 4 MPa was analyzed with the application of the advanced method of data exploration. The principal component analysis showed that the sample of the highest coal rank was characterized by lower values of parameters reflecting the development of the porous structure of chars. A negative correlation was also observed between the carbon content in a fuel and the evolution of the porous structure of chars at high pressure. The highest total pore volume of chars produced under 1 and 3 MPa and the highest micropore surface area under 3 MPa were reported for a carbonized fuel sample of the highest moisture content.

  18. Surface treatments for controlling corrosion rate of biodegradable Mg and Mg-based alloy implants.

    Science.gov (United States)

    Uddin, M S; Hall, Colin; Murphy, Peter

    2015-10-01

    Due to their excellent biodegradability characteristics, Mg and Mg-based alloys have become an emerging material in biomedical implants, notably for repair of bone as well as coronary arterial stents. However, the main problem with Mg-based alloys is their rapid corrosion in aggressive environments such as human bodily fluids. Previously, many approaches such as control of alloying materials, composition and surface treatments, have been attempted to regulate the corrosion rate. This article presents a comprehensive review of recent research focusing on surface treatment techniques utilised to control the corrosion rate and surface integrity of Mg-based alloys in both in vitro and in vivo environments. Surface treatments generally involve the controlled deposition of thin film coatings using various coating processes, and mechanical surfacing such as machining, deep rolling or low plasticity burnishing. The aim is to either make a protective thin layer of a material or to change the micro-structure and mechanical properties at the surface and sub-surface levels, which will prevent rapid corrosion and thus delay the degradation of the alloys. We have organised the review of past works on coatings by categorising the coatings into two classes-conversion and deposition coatings-while works on mechanical treatments are reviewed based on the tool-based processes which affect the sub-surface microstructure and mechanical properties of the material. Various types of coatings and their processing techniques under two classes of coating and mechanical treatment approaches have been analysed and discussed to investigate their impact on the corrosion performance, biomechanical integrity, biocompatibility and cell viability. Potential challenges and future directions in designing and developing the improved biodegradable Mg/Mg-based alloy implants were addressed and discussed. The literature reveals that no solutions are yet complete and hence new and innovative approaches are

  19. Surface treatments for controlling corrosion rate of biodegradable Mg and Mg-based alloy implants

    International Nuclear Information System (INIS)

    Uddin, M S; Hall, Colin; Murphy, Peter

    2015-01-01

    Due to their excellent biodegradability characteristics, Mg and Mg-based alloys have become an emerging material in biomedical implants, notably for repair of bone as well as coronary arterial stents. However, the main problem with Mg-based alloys is their rapid corrosion in aggressive environments such as human bodily fluids. Previously, many approaches such as control of alloying materials, composition and surface treatments, have been attempted to regulate the corrosion rate. This article presents a comprehensive review of recent research focusing on surface treatment techniques utilised to control the corrosion rate and surface integrity of Mg-based alloys in both in vitro and in vivo environments. Surface treatments generally involve the controlled deposition of thin film coatings using various coating processes, and mechanical surfacing such as machining, deep rolling or low plasticity burnishing. The aim is to either make a protective thin layer of a material or to change the micro-structure and mechanical properties at the surface and sub-surface levels, which will prevent rapid corrosion and thus delay the degradation of the alloys. We have organised the review of past works on coatings by categorising the coatings into two classes—conversion and deposition coatings—while works on mechanical treatments are reviewed based on the tool-based processes which affect the sub-surface microstructure and mechanical properties of the material. Various types of coatings and their processing techniques under two classes of coating and mechanical treatment approaches have been analysed and discussed to investigate their impact on the corrosion performance, biomechanical integrity, biocompatibility and cell viability. Potential challenges and future directions in designing and developing the improved biodegradable Mg/Mg-based alloy implants were addressed and discussed. The literature reveals that no solutions are yet complete and hence new and innovative approaches

  20. Surface treatments for controlling corrosion rate of biodegradable Mg and Mg-based alloy implants

    Science.gov (United States)

    Uddin, M S; Hall, Colin; Murphy, Peter

    2015-01-01

    Due to their excellent biodegradability characteristics, Mg and Mg-based alloys have become an emerging material in biomedical implants, notably for repair of bone as well as coronary arterial stents. However, the main problem with Mg-based alloys is their rapid corrosion in aggressive environments such as human bodily fluids. Previously, many approaches such as control of alloying materials, composition and surface treatments, have been attempted to regulate the corrosion rate. This article presents a comprehensive review of recent research focusing on surface treatment techniques utilised to control the corrosion rate and surface integrity of Mg-based alloys in both in vitro and in vivo environments. Surface treatments generally involve the controlled deposition of thin film coatings using various coating processes, and mechanical surfacing such as machining, deep rolling or low plasticity burnishing. The aim is to either make a protective thin layer of a material or to change the micro-structure and mechanical properties at the surface and sub-surface levels, which will prevent rapid corrosion and thus delay the degradation of the alloys. We have organised the review of past works on coatings by categorising the coatings into two classes—conversion and deposition coatings—while works on mechanical treatments are reviewed based on the tool-based processes which affect the sub-surface microstructure and mechanical properties of the material. Various types of coatings and their processing techniques under two classes of coating and mechanical treatment approaches have been analysed and discussed to investigate their impact on the corrosion performance, biomechanical integrity, biocompatibility and cell viability. Potential challenges and future directions in designing and developing the improved biodegradable Mg/Mg-based alloy implants were addressed and discussed. The literature reveals that no solutions are yet complete and hence new and innovative approaches

  1. Effect of surface treatments on the bond strengths of facing composite resins to zirconia copings.

    Science.gov (United States)

    Tsumita, M; Kokubo, Y; Kano, T

    2012-09-01

    The present study evaluated and compared the bond strength between zirconia and facing composite resin using different surface conditioning methods before and after thermocycling. Four primers, three opaque resins, and two facing composite resins were used, and 10 surface treatment procedures were conducted. The bond strength was measured before and after 4,000 cycles of thermocycling. The mean values of each group were statistically analyzed using one-way analysis of variance (ANOVA). The bond strengths of facing composite resins to zirconia after various treatments varied depending on the primers, opaque resins, body resins, and thermocycling. The application of primers and opaque resins to the zirconia surface after sandblasting is expected to yield strong bond strength of the facing composite resin (Estenia CG&B) even after thermocycling.

  2. Correlative study of scratch and wear behaviour of several surface treatments for uses in nuclear industries

    International Nuclear Information System (INIS)

    Guerout, F.; Zbinden, M.; Lina, A.; Clemendot, F.; Lelait, L.; Van Duysen, J.C.

    1992-06-01

    We have studied the scratch and wear behaviour of seven different surface treatments on an AISI 304L stainless steel substrate. These surface treatments have been elaborated by different processes: physical vapour deposition, ion nitriding, hypersonic projection and electrochemical deposition. The conventional scratch testing results show that the main surface damage feature is brittle cracking at the trailing edge of the indenter, but the cracking loads are broadly the same for all coatings considered here. So, we have carried out constant load scratch testing and analyzed the crack density inside of the track. The correlation between the crack density and the wear resistance, as measured in the GIBUS test, is satisfactory. This result shows the importance of the coating brittleness in the sliding-impact wear process. It is also necessary to adopt more precise and representative criterion for coating brittleness quantification

  3. Experimental studies of the stress state of the surface layer of detailat treatment with submerged jets

    Directory of Open Access Journals (Sweden)

    Олександр Олександрович Анділахай

    2015-03-01

    Full Text Available In the instrument and electrical industry was the use of the method of abrasive machining submerged jet, which is the most promising method for abrasive blasting of small parts of low stiffness. This method eliminates the main drawback сhip plants - abrasion channel nozzles or injection nozzles, but the state of the surface layer of machined parts are poorly understood and to make maximum use of the potential to provide the required quality parameters. The study of the state of the surfaces of parts resulting from abrasive blasting traditional methods, dedicated work, which define quality indicators: microhardness depth residual stress, as well as their nature (compressive, tensile. However, known from the literature values correspond to the conditions of surface treatment of parts in a fixed state with an abrasive material through the feed nozzle, and therefore the dynamics of the interaction of a single abrasive grain and significantly different parts. The process in question, and different modes of processing characteristics of the abrasive grains. In the paper, a series of experimental studies designed to assess the state of machined surfaces of parts as a result of abrasion submerged jets. It is established that during the treatment the non-oriented disorderly traces overlay the abrasive grains on the treated surface, thereby forming a tight skin layer thickness of 4 - 5 micrometers. Processed surface gets cold working, as evidenced by the study of microhardness before and after abrasive machining in a free state submerged jets

  4. Antimicrobial Effects of Three Different Treatment Modalities on Dental Implant Surfaces.

    Science.gov (United States)

    Larsen, Olav I; Enersen, Morten; Kristoffersen, Anne Karin; Wennerberg, Ann; Bunæs, Dagmar F; Lie, Stein Atle; Leknes, Knut N

    2017-12-01

    Resolution of peri-implant inflammation and re-osseointegration of peri-implantitis affected dental implants seem to be dependent on bacterial decontamination. The aims of the study were to evaluate the antimicrobial effects of 3 different instrumentations on a micro-textured dental implant surface contaminated with an avirulent or a virulent Porphyromonas gingivalis strain and to determine alterations to the implant surface following instrumentation. Forty-five dental implants (Straumann SLA) were allocated to 3 treatment groups: Er:YAG laser, chitosan brush, and titanium curette (10 implants each) and a positive (10 implants) and a negative (5 implants) control. Each treatment group and the positive control were split into subgroups of 5 implants subsequently contaminated with either the avirulent or virulent P. gingivalis strain. The antimicrobial effect of instrumentation was evaluated using checkerboard DNA-DNA hybridization. Implant surface alterations were determined using a light interferometer. Instrumentation significantly reduced the number of attached P. gingivalis ( P implant surface micro-texture. Neither the Er:YAG laser nor the chitosan brush significantly altered the implant surface. The 3 instrumentations appear to have a similar potential to remove P. gingivalis. The titanium curette significantly altered the microstructure of the implant surface.

  5. Influence of surface treatment on the crevice corrosion of super duplex stainless steel

    International Nuclear Information System (INIS)

    Malik, H.

    1997-01-01

    The aim of this work was to try and discover if changes i surface condition, derived through various methods could influence the resistance to crevice corrosion of super duplex stainless teel (SDS). Such data could then be employed to elucidate the main factors controlling crevice corrosion. Through the manipulation of these parameters it was envisaged that the crevice corrosion temperature of this material may be further advanced and to increase its application within harsher industrial environments. For this reason a series of crevice tests were performed on SDSS heat exchanger tubing both in the as received condition and after various surface treatments. Such modification was carried out by; shot blasting, passivation, pickling and combinations of annealing, shot blasting, pickling and passivation. Results have indicated that the main factor controlling the resistance to crevice corrosion is the level of Cr depletion within a few microns of the steel surface. Although various treatments such as shot blasting and pickling reduce Cr depletion by removal of surface material, the nature of the surface finish itself was not found to affect the corrosion resistance. An increase in Cr content from 20 to 25% within 2 microns of the surface of the tubing was able to increase the crevice corrosion temperature by 20 sub deg. C. (author)

  6. Surface Modification of Ceramic Membranes with Thin-film Deposition Methods for Wastewater Treatment

    KAUST Repository

    Jahangir, Daniyal

    2017-12-01

    Membrane fouling, which is caused by deposition/adsorption of foulants on the surface or within membrane pores, still remains a bottleneck that hampers the widespread application of membrane bioreactor (MBR) technology for wastewater treatment. Recently membrane surface modification has proved to be a useful method in water/wastewater treatment to improve the surface hydrophilicity of membranes to obtain higher water fluxes and to reduce fouling. In this study, membrane modification was investigated by depositing a thin film of same thickness of TiO2 on the surface of an ultrafiltration alumina membrane. Various thin-film deposition (TFD) methods were employed, i.e. electron-beam evaporation, sputter and atomic layer deposition (ALD), and a comparative study of the methods was conducted to assess fouling inhibition performance in a lab-scale anaerobic MBR (AnMBR) fed with synthetic municipal wastewater. Thorough surface characterization of all modified membranes was carried out along with clean water permeability (CWP) tests and fouling behavior by bovine serum albumin (BSA) adsorption tests. The study showed better fouling inhibition performance of all modified membranes; however the effect varied due to different surface characteristics obtained by different deposition methods. As a result, ALD-modified membrane showed a superior status in terms of surface characteristics and fouling inhibition performance in AnMBR filtration tests. Hence ALD was determined to be the best TFD method for alumina membrane surface modification for this study. ALD-modified membranes were further characterized to determine an optimum thickness of TiO2-film by applying different ALD cycles. ALD treatment significantly improved the surface hydrophilicity of the unmodified membrane. Also ALD-TiO2 modification was observed to reduce the surface roughness of original alumina membrane, which in turn enhanced the anti-fouling properties of modified membranes. Finally, a same thickness of ALD

  7. Impact of Surface Potential on Apatite Formation in Ti Alloys Subjected to Acid and Heat Treatments.

    Science.gov (United States)

    Yamaguchi, Seiji; Hashimoto, Hideki; Nakai, Ryusuke; Takadama, Hiroaki

    2017-09-24

    Titanium metal (Ti) and its alloys are widely used in orthopedic and dental fields. We have previously shown that acid and heat treatment was effective to introduce bone bonding, osteoconduction and osteoinduction on pure Ti. In the present study, acid and heat treatment with or without initial NaOH treatment was performed on typical Ti-based alloys used in orthopedic and dental fields. Dynamic movements of alloying elements were developed, which depended on the kind of treatment and type of alloy. It was found that the simple acid and heat treatment enriched/remained the alloying elements on Ti-6Al-4V, Ti-15Mo-5Zr-3Al and Ti-15Zr-4Nb-4Ta, resulting in neutral surface charges. Thus, the treated alloys did not form apatite in a simulated body fluid (SBF) within 3 days. In contrast, when the alloys were subjected to a NaOH treatment prior to an acid and heat treatment, alloying elements were selectively removed from the alloy surfaces. As a result, the treated alloys became positively charged, and formed apatite in SBF within 3 days. Thus, the treated alloys would be useful in orthopedic and dental fields since they form apatite even in a living body and bond to bone.

  8. Electrochemical Surface Treatment of a β-titanium Alloy to Realize an Antibacterial Property and Bioactivity

    Directory of Open Access Journals (Sweden)

    Yusuke Tsutsumi

    2016-03-01

    Full Text Available In this study, micro-arc oxidation (MAO was performed on a β-type titanium alloy, namely, Ti-29Nb-13Ta-4.6Zr alloy (TNTZ, to improve not only its antibacterial property but also bioactivity in body fluids. The surface oxide layer formed on TNTZ by MAO treatment in a mixture of calcium glycerophosphate, calcium acetate, and silver nitrate was characterized using surface analyses. The resulting porous oxide layer was mainly composed of titanium oxide, and it also contained calcium, phosphorus, and a small amount of silver, all of which were incorporated from the electrolyte during the treatment. The MAO-treated TNTZ showed a strong inhibition effect on anaerobic Gram-negative bacteria when the electrolyte contained more than 0.5 mM silver ions. The formation of calcium phosphate on the surface of the specimens after immersion in Hanks’ solution was evaluated to determine the bioactivity of TNTZ with sufficient antibacterial property. As a result, thick calcium phosphate layers formed on the TNTZ specimen that underwent MAO treatment, whereas no precipitate was observed on TNTZ without treatment. Thus, the MAO treatment of titanium-based alloys is confirmed to be effective in realizing both antibacterial and bioactive properties.

  9. Fracture resistance of dental nickel–titanium rotary instruments with novel surface treatment: Thin film metallic glass coating

    Directory of Open Access Journals (Sweden)

    Chih-Wen Chi

    2017-05-01

    Conclusion: The novel surface treatment of Ti-Zr-B thin film metallic glass on dental NiTi rotary files can effectively improve the fatigue fracture resistance by offering a smooth coated surface with amorphous microstructure.

  10. Surface treatment of titanium by a polydimethylsiloxane coating on bond strength of resin to titanium.

    Science.gov (United States)

    Lung, Christie Ying Kei; Liu, Dan; Matinlinna, Jukka Pekka

    2015-01-01

    To evaluate the in vitro effect of titanium surface treatment by a polydimethylsiloxane coating on the shear bond strength of a resin composite cement to titanium. The titanium samples (40×30mm) were divided into 4 groups (n=12). A control group was surface treated by sandblasting using 110µm silica-coated alumina powder at a constant pressure of 300kPa for 15s/1cm(2). For other three test groups, a polydimethylsiloxane silicone grease was applied onto the surface. The samples were subjected to thermal treatment in air at temperatures of 800°C, 1000°C, and 1100°C for 2h. A silane coupling agent was then applied and a resin composite stub was bonded using a polyethylene mold. The samples were submitted to three different storage conditions: dry storage, water storage in deionized water at 37°C for 30 days and thermo-cycled for 6000 cycles between 5.0 and 55.0°C. The shear bond strengths of all test groups were determined using a universal testing machine. Data were analyzed by two-way ANOVA and Tukey HSD (psurface morphology of titanium and elemental composition were examined with SEM and EDAX. The results showed that there was a significant difference for different surface treatments (psurface after thermal treatment of the coating. Surface treatment of titanium with a polydimethylsiloxane coating at 1000°C and 1100°C curing provides sufficient resin bonding for clinical services. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Effect of zirconia surface treatment on zirconia/veneer interfacial toughness evaluated by fracture mechanics method.

    Science.gov (United States)

    Wang, Gaoqi; Zhang, Song; Bian, Cuirong; Kong, Hui

    2014-07-01

    The aim of this study was to evaluate the effect of the airborne-particle abrasion and liner application on the interfacial toughness between veneering porcelain and zirconia core by means of a fracture mechanics test. Beam-shaped zirconia specimens were sectioned and divided into 4 groups according to different surface treatments as follows: Group C (control): no treatment; Group L: application of liner; Group A: airborne-particle abrasion with Al2O3 (sandblasting); and Group AL: airborne-particle abrasion and application of liner. The zirconia surfaces before and after sandblasting were observed and analyzed by SEM and white light interferometer. Specimens of each pretreated group were veneered with 3 core/veneer thickness ratios of 2:3, 1:1, and 3:2, corresponding to 3 phase angles respectively. Fracture mechanics test was performed on each specimen, the energy release rate G and phase angle ψ were calculated to characterize interfacial toughness. The experimental data were analyzed statistically using three-way ANOVA and the Tukey's HSD test. The surfaces of fractured specimens were examined by SEM and EDX. At each phase angle, the interfaces with no treatment had higher mean G values than that of other groups. All the specimens showed mixed failure mode with residual veneer or liner on the zirconia surfaces. The toughness of zirconia/veneer interface with no treatment is significantly higher than that of interfaces subjected to liner application and airborne-particle abrasion. Liner application and airborne-particle abrasion seem to reduce zirconia/veneer interfacial toughness. Therefore, the two surface treatment methods should be applied with caution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Influence of different surface treatments on the fracture toughness of a commercial ZTA dental ceramic

    Directory of Open Access Journals (Sweden)

    Flavio Teixeira da Silva

    2007-03-01

    Full Text Available The objective of this study was to investigate how mechanical surface treatments performed for removal of excess of molten glass, influence the fracture toughness of a dental zirconia toughened alumina (In-Ceram® Zirconia. Infiltrated ZTA disks were submitted to three different surface treatments (grinding, sandblasting and grinding + sandblasting + annealing. Fracture toughness was accessed through indentation strength test (IS. X ray diffraction was used to investigate the metastability of tetragonal zirconia particles under all treatments proposed. Kruskall-Wallis non-parametrical test and Weibull statistics were used to analyze the results. Grinding (group 1 introduced defects which decreased the fracture toughness and reliability, presenting the lowest K IC. On the other hand, grinding followed by sandblasting and annealing (group 3 presented the highest K IC. Sandblasting (group 2 presented the highest reliability but lower K IC compared to group 3.

  13. Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff.

    Science.gov (United States)

    Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Cahn, Michael

    2017-05-15

    Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may be treated with simple systems designed to promote sorption of contaminants to vegetation and soils and promote infiltration. Two example systems are described: a bioswale treatment system for urban stormwater treatment, and a vegetated drainage ditch for treating agriculture irrigation runoff. Both have similar attributes that reduce contaminant loading in runoff: vegetation that results in sorption of the contaminants to the soil and plant surfaces, and water infiltration. These systems may also include the integration of granulated activated carbon as a polishing step to remove residual contaminants. Implementation of these systems in agriculture and urban watersheds requires system monitoring to verify treatment efficacy. This includes chemical monitoring for specific contaminants responsible for toxicity. The current paper emphasizes monitoring of current use pesticides since these are responsible for surface water toxicity to aquatic invertebrates.

  14. Thermoluminescence and cathodoluminescence studies of calcite and MgO: surface defects and heat treatment

    International Nuclear Information System (INIS)

    Goeksu, H.Y.; Brown, L.M.

    1988-01-01

    Some of the problems which preclude accurate thermoluminescence (TL) dating of geologically formed calcite stem from different sample pre-treatment procedures, such as grinding, drilling or pre-heating. It has long been known that grinding can introduce spurious TL in calcite, but there have been wide differences of opinion as to the magnitude of the influence and its importance. Therefore, various grinding and acid-washing procedures have been suggested to avoid spurious thermoluminescence. Various models have been developed to explain the mechanism. We have studied the changes in thermoluminescence (TL) and cathodoluminescence (CL) properties as well as in the spectral composition of the glow from calcite and MgO due to surface defects and heat treatment. It is found that both laboratory heat treatment and surface indents give rise to changes in TL efficiency. (author)

  15. The effect of phosphorus and sulfur treatment on the surface properties of InP

    Science.gov (United States)

    Iyer, R.; Chang, R. R.; Dubey, A.; Lile, D. L.

    1988-01-01

    Experimental results are presented for InP surfaces treated by using red phosphorus as a source to create an excess overpressure of phosphorus during annealing and prior to silicon dioxide deposition. The surface has been probed by in situ photoluminescence, noncontacting remote gate C-V, and conventional high-frequency and quasi-static C-V methods. A study has also been made of the surface of sulfurized InP following heating in aqueous (NH4)2S(x). MISFETs fabricated using the benefits of these surface treatments show high transconductances and stabilities approaching those of thermal SiO2/Si with less than 5-percent variation in drain current over a 12-hr period.

  16. Influence of TiO{sub 2} Surface Properties on Water Pollution Treatment and Photocatalytic Activity

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Min [Southwest Univ. of Science and Technology, Mianyang (China)

    2013-03-15

    The titania surface showed different characteristics depending on the charge of the dye molecules. Compared with the MB molecules, the negatively charged MO molecules strongly adsorbed on the titania surface. Furthermore, the decomposition kinetics of the dye molecules by the photocatalytic activity also deepened with the charge of the dye molecules. The relation between the UV irradiation time and the molar ratio of the decomposed dye molecules followed the Avrami equation. According to the results of the analysis by using the Avrami equation, the MO molecules were decomposed on the titania particle surface. In contrast, the MB molecules were decomposed in the aqueous solution. The difference in kinetics was related to the interaction of the dye molecules and the titania surface. These preferential adsorption and decomposition characteristics will improve its applications in water pollution treatment.

  17. Assessment of airborne nanoparticles present in industry of aluminum surface treatments.

    Science.gov (United States)

    Santos, R J; Vieira, M T

    2017-03-01

    Conventional industrial processes are emission sources of unintended nanoparticles which are potentially harmful for the environment and human health. The aim of this study is to assess airborne nanoparticle release from aluminum surface treatment processes in various workplaces. Two direct reading instruments, a scanning mobility particle sizer to measure size distribution and a nanoparticle surface area monitoring to measure the surface area of particles deposited in the human lung, were employed to perform area monitoring. The lacquering paint was the process which released the highest concentration of particles from 10-487 nm (7.06 × 10 6 particles/cm 3 ). The lacquering baths process emitted particles of the largest average size (76.9 nm) and the largest surface area deposited in the human lung (167.4 µm 2 /cm 3 ). Conversely, the anodizing bath process generated particles of the smallest average size (44.3 nm) and the lowest human lung-deposited surface area (1.2 µm 2 /cm 3 ). The total number of particles and the surface area can only be fairly correlated for environments in which the surface area presented higher values. The transmission electron microscopy analysis confirmed the presence of aluminum oxide particles of different dimensions near the LB and AB areas and polymeric-based particles near the LP areas. The findings of this study indicated that lacquering and anodizing surface treatments are indeed responsible for the emission of airborne nanoparticles. It also highlights the importance of control strategies as a means of protecting workers' health and environment.

  18. Creation of fluorocarbon barriers on surfaces of starch-based products through cold plasma treatment

    Science.gov (United States)

    Han, Yousoo

    Two kinds of starch foam trays (starch and aspen-starch foam trays) were produced using a lab model baking machine. Surfaces of the trays were treated with CF4 and SF6 plasma to create fluorine-rich layers on the surfaces, which might show strong water resistance. The plasma parameters, such like RF power, gas pressure and reaction time, were varied to evaluate the effects of each parameter on fluorination of surfaces. The atomic concentrations of fluorine, oxygen and carbon on samples' surfaces were earned from ESCA (electron spectroscopy for chemical analysis) and contact angles of sample surfaces were measured for hydrophobicity. For water resistance of plasma treated surfaces, liquid water uptake and water vapor uptake test were performed. Also, equilibrium moisture contents of unmodified and plasma treated samples were measured to evaluate biodegradability of plasma treated samples. Fluorine-rich barriers were created on sample surfaces treated with CF 4 and SF6 plasma. The fluorine atomic concentrations of treated sample surfaces were ranged from 34.4% to 64.4% (CF4 treatment) and 43.6% to 57.9% (SF6 treatment). It was found at both plasma gases that plasma parameters affected total fluorine concentration and carbon-peak shapes in ESCA surveys, which imply different distributions of mono- or multi-fluoro carbon's contents. In various reaction times, it was found that total fluorine contents were decreased after a critical point as the reaction time was prolonged, which may imply that a dominant mechanism has been changed from deposition or functionalization to etching. Oxygen atomic concentration was decreased at sample surfaces treated by both plasmas. In the case of SF6 plasma, it was proved that the removal of oxygen surely occurred because there was no addition of sulfur species. Plasma treated sample surfaces had high contact angles with distilled water up to 150° and the high values of angles have been kept constant up to for 15 minutes. Fluorine

  19. The effects of zeolite molecular sieve based surface treatments on the properties of wool fabrics

    Energy Technology Data Exchange (ETDEWEB)

    Carran, Richard S.; Ghosh, Arun, E-mail: Arun.Ghosh@agresearch.co.nz; Dyer, Jolon M.

    2013-12-15

    Wool is a natural composite fiber, with keratin and keratin-associated proteins as the key molecular components. The outermost surface of wool fibers comprises a hydrophobic lipid layer that can lead to unsatisfactory processing and properties of fabric products. In this study, molecular sieve 5A, a Na{sup +} and Ca{sup 2+} exchanged type A zeolite with a 1:1 Si:Al ratio was integrated onto the surface of wool using 3-mercaptopropyl trimethoxy silane. The resultant surface morphology, hydrophilicity and mechanical performance of the treated wool fabrics were then evaluated. Notably, the surface hydrophilicity of wool was observed to increase dramatically. When wool was treated with a dispersion of 2 wt% acetic acid, 2.5 wt% zeolite and 0.3 wt% or more silane, the water contact angle was observed to decrease from an average value of 148° to 0° over a period of approximately 30 s. Scanning electron microscopic imaging indicated good coverage of the wool surface with zeolite particles, with infrared spectroscopic evaluation indicating strong bonding of the dealuminated zeolite to wool keratins. This application of zeolite showed no adverse effects on the tensile and other mechanical properties of the fabric. This study indicates that zeolite-based treatment is a potentially efficient approach to increasing the surface hydrophilicity and modifying other key surface properties of wool and wool fabrics.

  20. Comparison of KrF and ArF excimer laser treatment of biopolymer surface

    Energy Technology Data Exchange (ETDEWEB)

    Michaljaničová, I. [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic); Slepička, P., E-mail: petr.slepicka@vscht.cz [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic); Heitz, J.; Barb, R.A. [Institute of Applied Physics, Johannes Kepler University Linz, A-4040 Linz (Austria); Sajdl, P. [Department of Power Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic); Švorčík, V. [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague (Czech Republic)

    2015-06-01

    Highlights: • The influence of ArF and KrF laser on biopolymer surface was determined. • ArF laser acts predominantly on biopolymer surface. • PHB roughness is increased similarly for both applied wavelengths. • Roughness of nanostructures can be precisely controlled. • ArF laser introduces nitrogen on PHB surface. - Abstract: The goal of this work was the investigation of the impact of two different excimer lasers on two biocompatible and biodegradable polymers (poly-L-lactide and poly hydroxybutyrate). Both polymers find usage in medical and pharmaceutical fields. The polymers were modified by KrF and ArF excimer lasers. Subsequently the impact on surface morphology, surface chemistry changes, and thermal properties was studied by means of confocal and AFM microscopy, FTIR and XPS spectroscopy and DSC calorimetry. Under the same conditions of laser treatment it was observed that ArF laser causes more significant changes on surface chemistry, surface morphology and pattern formation on the polymers under investigation. The data obtained in this work can be used for a wide range of possible applications, in tissue engineering or in combination with metallization in electronics, e.g. for biosensors.

  1. Surface changes of biopolymers PHB and PLLA induced by Ar+ plasma treatment and wet etching

    Science.gov (United States)

    Slepičková Kasálková, N.; Slepička, P.; Sajdl, P.; Švorčík, V.

    2014-08-01

    Polymers, especially group of biopolymers find potential application in a wide range of disciplines due to their biodegradability. In biomedical applications these materials can be used as a scaffold or matrix. In this work, the influence of the Ar+ plasma treatment and subsequent wet etching (acetone/water) on the surface properties of polymers were studied. Two biopolymers - polyhydroxybutyrate with 8% polyhydroxyvalerate (PHB) and poly-L-lactic acid (PLLA) were used in these experiments. Modified surface layers were analyzed by different methods. Surface wettability was characterized by determination of water contact angle. Changes in elemental composition of modified surfaces were performed by X-ray Photoelectron Spectroscopy (XPS). Surface morphology and roughness was examined using Atomic Force Microscopy (AFM). Gravimetry method was used to study the mass loss. It was found that the modification from both with plasma and wet etching leads to dramatic changes of surface properties (surface chemistry, morphology and roughness). Rate of changes of these features strongly depends on the modification parameters.

  2. The effects of zeolite molecular sieve based surface treatments on the properties of wool fabrics

    Science.gov (United States)

    Carran, Richard S.; Ghosh, Arun; Dyer, Jolon M.

    2013-12-01

    Wool is a natural composite fiber, with keratin and keratin-associated proteins as the key molecular components. The outermost surface of wool fibers comprises a hydrophobic lipid layer that can lead to unsatisfactory processing and properties of fabric products. In this study, molecular sieve 5A, a Na+ and Ca2+ exchanged type A zeolite with a 1:1 Si:Al ratio was integrated onto the surface of wool using 3-mercaptopropyl trimethoxy silane. The resultant surface morphology, hydrophilicity and mechanical performance of the treated wool fabrics were then evaluated. Notably, the surface hydrophilicity of wool was observed to increase dramatically. When wool was treated with a dispersion of 2 wt% acetic acid, 2.5 wt% zeolite and 0.3 wt% or more silane, the water contact angle was observed to decrease from an average value of 148° to 0° over a period of approximately 30 s. Scanning electron microscopic imaging indicated good coverage of the wool surface with zeolite particles, with infrared spectroscopic evaluation indicating strong bonding of the dealuminated zeolite to wool keratins. This application of zeolite showed no adverse effects on the tensile and other mechanical properties of the fabric. This study indicates that zeolite-based treatment is a potentially efficient approach to increasing the surface hydrophilicity and modifying other key surface properties of wool and wool fabrics.

  3. Influence of surface treatments on the shear bond strength of orthodontic brackets to porcelain

    Science.gov (United States)

    Wang, Cong; Zeng, Jishan; Wang, Shaoan; Yang, Zheng; Huang, Qian; Chen, Pixiu; Zhou, Shujuan; Liu, Xiaoqing

    2008-11-01

    The purpose of this study was to investigate the effect of various surface treatments after different storage time and thermocycling on the shear bond strength of orthodontic brackets to the feldspathic porcelain surfaces. 128 disc-shaped porcelain specimens were randomly assigned to the following surface treatments: 9.6% HFA, 9.6% HFA combined with silane, 50 μ aluminum trioxide sandblasting followed by silane and application of silane after 37% phosphoric acid. Metal or ceramic brackets were bonded onto each treated porcelain facet with light cured resin. The samples were stored in 37 °C water 1 day or 7 days, thermocycled 500 times from 5 to 55 °C. The shear bond strengths were measured (1 mm/min), and statistically analyzed. The bond failure sites were classified according to ARI system. The surface of the glazed, sandblasted, hydrofluoric and phosphoric acid etched porcelain were examined with SEM. All groups achieved reasonable bond strengths to withstand the application of orthodontic forces. Water storage for 7 days caused lower shear bond strength than that of 1 day. But there is no statistically significant difference between the two groups. The mean shear bond strength provided by ceramic bracket with mechanical retention had no statistical difference with that of metal bracket. Therefore, the optimal treatment for orthodontic brackets bonding to feldspathic porcelain was to apply phosphoric acid combined with silane.

  4. Effects of surface treatment of provisional crowns on the shear bond strength of brackets.

    Science.gov (United States)

    de Almeida, Josiane Xavier; Deprá, Mauren Bitencourt; Marquezan, Mariana; Retamoso, Luciana Borges; Tanaka, Orlando

    2013-01-01

    To assess the adhesive resistance of metallic brackets bonded to temporary crowns made of acrylic resin after different surface treatments. 180 specimens were made of Duralay and randomly divided into 6 groups (n = 30) according to surface treatment and bonding material: G1 - surface roughening with Soflex and bonding with Duralay; G2 - roughening with aluminum oxide blasting and bonding with Duralay; G3 - application of monomer and bonding with Duralay; G4 - roughening with Soflex and bonding with Transbond XT; G5 - roughening with aluminum oxide blasting and bonding with Transbond XT and G6 - application of monomer and bonding with Transbond. The results were statistically assessed by ANOVA/Games-Howell. The means (MPa) were: G1= 18.04, G2= 22.64, G3= 22.4, G4= 9.71, G5= 11.23, G6= 9.67. The Adhesive Remnant Index (ARI) ranged between 2 and 3 on G1, G2 and G3 whereas in G4, G5 and G6 it ranged from 0 to 1, showing that only the material affects the pattern of adhesive flaw. The surface treatment and the material influenced adhesive resistance of brackets bonded to temporary crowns. Roughening by aluminum blasting increased bond strength when compared to Soflex, in the group bonded with Duralay. The bond strength of Duralay acrylic resin was superior to that of Transbond XT composite resin.

  5. Effects of surface treatment of provisional crowns on the shear bond strength of brackets

    Directory of Open Access Journals (Sweden)

    Josiane Xavier de Almeida

    2013-08-01

    Full Text Available OBJECTIVE: To assess the adhesive resistance of metallic brackets bonded to temporary crowns made of acrylic resin after different surface treatments. METHODS: 180 specimens were made of Duralay and randomly divided into 6 groups (n = 30 according to surface treatment and bonding material: G1 - surface roughening with Soflex and bonding with Duralay; G2 - roughening with aluminum oxide blasting and bonding with Duralay; G3 - application of monomer and bonding with Duralay; G4 - roughening with Soflex and bonding with Transbond XT; G5 - roughening with aluminum oxide blasting and bonding with Transbond XT and G6: application of monomer and bonding with Transbond. The results were statistically assessed by ANOVA/Games-Howell. RESULTS: The means (MPa were: G1= 18.04, G2= 22.64, G3= 22.4, G4= 9.71, G5= 11.23, G6= 9.67. The Adhesive Remnant Index (ARI ranged between 2 and 3 on G1, G2 and G3 whereas in G4, G5 and G6 it ranged from 0 to 1, showing that only the material affects the pattern of adhesive flaw. CONCLUSION: The surface treatment and the material influenced adhesive resistance of brackets bonded to temporary crowns. Roughening by aluminum blasting increased bond strength when compared to Soflex, in the group bonded with Duralay. The bond strength of Duralay acrylic resin was superior to that of Transbond XT composite resin.

  6. Effects of mechanical and chemical surface treatments on the resin-glass ceramic adhesion properties.

    Science.gov (United States)

    Sattabanasuk, Vanthana; Charnchairerk, Paleenee; Punsukumtana, Lada; Burrow, Michael F

    2017-08-01

    Intraoral repair of fractured ceramic restorations using resin composite is practical for dental treatment. In the present study, we investigated whether differences in surface treatments for glass ceramic would affect resin adhesion. Leucite-reinforced glass ceramic plates (IPS Empress Esthetic) were ground with 320-grit silicon carbide paper, cleaned using phosphoric acid, and then etched with hydrofluoric acid (IPS Ceramic Etching Gel) or left unetched, and silanized using silane coupling agent (RelyX Ceramic Primer) or kept unsilanized. Either conventional (Adper Scotchbond Multi-Purpose) or universal (Scotchbond Universal) adhesive was used to bond the resin composite to ceramic surfaces. Specimens were subjected to microshear test after 37°C water storage for 24 h, and fractured surfaces were examined. Ceramic surface hydrophobicity after treatments was verified with contact angle measurements. Data were analyzed using anova and Tukey's tests. Regardless of the adhesive tested, hydrofluoric acid-etched ceramics showed higher bond strengths. Ceramic primer application improved resin bonding, even in non-etched groups, and also influenced fractography (P ceramics treated with ceramic primer were higher than those treated with silane-containing universal adhesive (P resin adhesion to glass ceramic. Universal adhesive seems to not function in the same manner as a silane coupling agent. © 2016 John Wiley & Sons Australia, Ltd.

  7. Distributed approximation of Pareto surfaces in multicriteria radiation therapy treatment planning

    International Nuclear Information System (INIS)

    Bokrantz, Rasmus

    2013-01-01

    We consider multicriteria radiation therapy treatment planning by navigation over the Pareto surface, implemented by interpolation between discrete treatment plans. Current state of the art for calculation of a discrete representation of the Pareto surface is to sandwich this set between inner and outer approximations that are updated one point at a time. In this paper, we generalize this sequential method to an algorithm that permits parallelization. The principle of the generalization is to apply the sequential method to an approximation of an inexpensive model of the Pareto surface. The information gathered from the model is sub-sequently used for the calculation of points from the exact Pareto surface, which are processed in parallel. The model is constructed according to the current inner and outer approximations, and given a shape that is difficult to approximate, in order to avoid that parts of the Pareto surface are incorrectly disregarded. Approximations of comparable quality to those generated by the sequential method are demonstrated when the degree of parallelization is up to twice the number of dimensions of the objective space. For practical applications, the number of dimensions is typically at least five, so that a speed-up of one order of magnitude is obtained. (paper)

  8. Distributed approximation of Pareto surfaces in multicriteria radiation therapy treatment planning.

    Science.gov (United States)

    Bokrantz, Rasmus

    2013-06-07

    We consider multicriteria radiation therapy treatment planning by navigation over the Pareto surface, implemented by interpolation between discrete treatment plans. Current state of the art for calculation of a discrete representation of the Pareto surface is to sandwich this set between inner and outer approximations that are updated one point at a time. In this paper, we generalize this sequential method to an algorithm that permits parallelization. The principle of the generalization is to apply the sequential method to an approximation of an inexpensive model of the Pareto surface. The information gathered from the model is sub-sequently used for the calculation of points from the exact Pareto surface, which are processed in parallel. The model is constructed according to the current inner and outer approximations, and given a shape that is difficult to approximate, in order to avoid that parts of the Pareto surface are incorrectly disregarded. Approximations of comparable quality to those generated by the sequential method are demonstrated when the degree of parallelization is up to twice the number of dimensions of the objective space. For practical applications, the number of dimensions is typically at least five, so that a speed-up of one order of magnitude is obtained.

  9. Recent Trends in Surface Treatment Methods for Bonding Composite Cement to Zirconia: A Reveiw.

    Science.gov (United States)

    Khan, Aftab Ahmed; Al Kheraif, Abdul Aziz A; Jamaluddin, Syed; Elsharawy, Mohamad; Divakar, Darshan Devang

    To evaluate the in vitro studies conducted in the last six years on new zirconia materials to discover and explore current trends in bonding composite cement to zirconia substrate. An in-depth review of the in vitro studies performed between 2010 and 2016 was conducted, focusing on the current trends in surface conditioning methods for zirconia ceramic. PubMed was used for searching the literature. Resin composite bonding to zirconia, zirconia surface coating, and zirconia surface treatment method were the keywords used. Complete scientific articles were reviewed and evaluated for appropriateness. The literature survey showed a variety of surface treatment techniques comprising grit blasting (laboratory or chairside) with or without silica-coated alumina particles, the use of materials containing phosphate monomers, different silanes and primers, laser irradiation, Si vapor-phase deposition, and selective infiltration etching. The problem of composite cement bonding to zirconia has yet to be definitively solved. Nevertheless, the application of phosphate monomer on tribochemically silica-coated zirconia surfaces is currently the least complicated and most efficaceous means of bonding composite cement to zirconia. Selective infiltration etching seems to be a promising technique for establishing a durable bond between composite cement and zirconia, and should be studied further.

  10. Nano-structuring of PTFE surface by plasma treatment, etching, and sputtering with gold

    International Nuclear Information System (INIS)

    Reznickova, Alena; Kolska, Zdenka; Hnatowicz, Vladimir; Svorcik, Vaclav

    2011-01-01

    Properties of pristine, plasma modified, and etched (by water and methanol) polytetrafluoroethylene (PTFE) were studied. Gold nanolayers sputtered on this modified PTFE have been also investigated. Contact angle, measured by goniometry, was studied as a function of plasma exposure and post-exposure aging times. Degradation of polymer chains was examined by etching of plasma modified PTFE in water or methanol. The amount of ablated and etched layer was measured by gravimetry. In the next step the pristine, plasma modified, and etched PTFE was sputtered with gold. Changes in surface morphology were observed using atomic force microscopy. Chemical structure of modified polymers was characterized by X-ray photoelectron spectroscopy (XPS). Surface chemistry of the samples was investigated by electrokinetic analysis. Sheet resistance of the gold layers was measured by two-point technique. The contact angle of the plasma modified PTFE decreases with increasing exposure time. The PTFE amount, ablated by the plasma treatment, increases with the plasma exposure time. XPS measurements proved that during the plasma treatment the PTFE macromolecular chains are degraded and oxidized and new –C–O–C–, –C=O, and –O–C=O groups are created in modified surface layer. Surface of the plasma modified PTFE is weakly soluble in methanol and intensively soluble in water. Zeta potential and XPS shown dramatic changes in PTFE surface chemistry after the plasma exposure, water etching, and gold deposition. When continuous gold layer is formed a rapid decrease of the sheet resistance of the gold layer is observed.

  11. Orienting Block Copolymer Thin Films via Entropy and Surface Plasma Treatment

    Science.gov (United States)

    Ho, Rong-Ming; Lu, Kai-Yuan; Lo, Ting-Ya; Dehghan, Ashkan; Shi, An-Chang; Prokopios, Georgopanos; Avgeropoulos, Apostolos

    Controlling the orientation of nanostructured thin films of block copolymers (BCPs) is essential for next generation lithography. In the thin-film state, how to achieve the perpendicular orientation of the nanostructured microdomains remains challenging due to the interfacial effects from the air and also the substrate, especially for the blocks with silicon containing segments which usually have different surface energies, favoring parallel microdomain orientation. Here, we show that entropic effect can be used to control the orientation of BCP thin films. Specifically, we used the architecture of star-block copolymers consisting of polystyrene (PS) and poly(dimethylsiloxane) (PDMS) blocks to regulate the entropic contribution to the self-assembled nanostructures. Moreover, we aim to achieve the formation of perpendicular orientation from the air surface via surface plasma treatment to neutralize the interfacial energy difference. By combining the architecture effect (entropy effect) on BCP self-assembly and the surface plasma treatment (enthalpy effect), well-defined perpendicular PDMS microdomains in the PS-b-PDMS thin film can be formed from the bottom of non-neutral substrate and the top of the thin film surface, giving great potential for lithographic applications.

  12. Surface treatment to form a dispersed Y2O3 layer on Zircaloy-4 tubes

    Science.gov (United States)

    Jung, Yang-Il; Kim, Hyun-Gil; Guim, Hwan-Uk; Lim, Yoon-Soo; Park, Jung-Hwan; Park, Dong-Jun; Yang, Jae-Ho

    2018-01-01

    Zircaloy-4 is a traditional zirconium-based alloy developed for application in nuclear fuel cladding tubes. The surfaces of Zircaloy-4 tubes were treated using a laser beam to increase their mechanical strength. Laser beam scanning of a tube coated with yttrium oxide (Y2O3) resulted in the formation of a dispersed oxide layer in the tube's surface region. Y2O3 particles penetrated the Zircaloy-4 during the laser treatment and were distributed uniformly in the surface region. The thickness of the dispersed oxide layer varied from 50 to 140 μm depending on the laser beam trajectory. The laser treatment also modified the texture of the tube. The preferred basal orientation along the normal to the tube surface disappeared, and a random structure appeared after laser processing. The most obvious result was an increase in the mechanical strength. The tensile strength of Zircaloy-4 increased by 10-20% with the formation of the dispersed oxide layer. The compressive yield stress also increased, by more than 15%. Brittle fracture was observed in the surface-treated samples during tensile and compressive deformation at room temperature; however, the fracture behavior was changed in ductile at elevated temperatures.

  13. How does the surface treatment change the cytocompatibility of implants made by selective laser melting?

    Science.gov (United States)

    Matouskova, Lucie; Ackermann, Michal; Horakova, Jana; Capek, Lukas; Henys, Petr; Safka, Jiri

    2018-04-01

    The study investigates the potential for producing medical components via Selective Laser Melting technology (SLM). The material tested consisted of the biocompatible titanium alloy Ti6Al4V. The research involved the testing of laboratory specimens produced using SLM technology both in vitro and for surface roughness. The aim of the research was to clarify whether SLM technology affects the cytocompatibility of implants and, thus, whether SLM implants provide suitable candidates for medical use following zero or minimum post-fabrication treatment. Areas covered: The specimens were tested with an osteoblast cell line and, subsequently, two post-treatment processes were compared: non-treated (as-fabricated) and glass-blasted. Interactions with MG-63 cells were evaluated by means of metabolic MTT assay and microscope techniques (scanning electron microscopy, fluorescence microscopy). Surface roughness was observed on both the non-treated and glass-blasted SLM specimens. Expert Commentary: The research concluded that the glass-blasting of SLM Ti6Al4V significantly reduces surface roughness. The arithmetic mean roughness Ra was calculated at 3.4 µm for the glass-blasted and 13.3 µm for the non-treated surfaces. However, the results of in vitro testing revealed that the non-treated surface was better suited to cell growth.

  14. Effect of Surface Polishing on Mercury Release from Dental Amalgam After Treatment 16% Carbamide Peroxide Gel

    Directory of Open Access Journals (Sweden)

    Z. Khamverdi

    2011-03-01

    Full Text Available Objectives: This study evaluated the effect of surface polishing on mercury release from dental amalgam after treatment with 16% carbamide peroxide gel.Materials and Methods: Ninety-six samples from two different amalgam brands were prepared in truncated cone-shaped PVC polymer molds with an external surface area of 195 mm². Half of the specimens were polished with green and red rubber, a brush and tin oxide paste at low speed. Samples were treated with 16% carbamide peroxide gel intubes containing 3 mL of carbamide peroxide gel and 0.1 mL of distilled water for 14 and 28 hours. Subsequently, carbamide peroxide gel on the sample surfaces was rinsed away with 7.0 mL of distilled water until the volume of each tube increased to 10 mL. Themercury level of each solution was measured using the VAV–440 mercury analyzer system.Considering the surface area of each amalgam disc, mercury amounts were calculated in μg ⁄mm². Data were analyzed using two-way ANOVA.Results: There were significant differences between the mean levels of mercury release from polished vs. unpolished amalgam surfaces after treatment with 16% carbamide peroxide.Increasing the storage time from 14 to 28 hours did not result in significant changes in the amount of mercury release. There was no significant interaction effect between amalgam surface polish and storage time statistically.Conclusion: Polished amalgam restorations release less mercury after treatment with carbamide peroxide bleaching gel in comparison with unpolished amalgam restorations.

  15. Removal and treatment of radioactive, organochlorine and heavy metal contaminants from solid surfaces

    International Nuclear Information System (INIS)

    Grieco, S.A.; Neubauer, E.D.; Rhea, J.R.; Escue, L.S.

    1996-01-01

    The U.S. Department of Energy (DOE) is defining decontamination and decommissioning (D ampersand D) obligations at its sites. Current D ampersand D activities are Generally labor intensive, use chemical reagents that are difficult to treat, and may expose workers to radioactive and hazardous chemicals. Therefore, new technologies are desired that minimize waste, allow much of the decommissioned materials to be reused rather than disposed of as waste, and produce wastes that will meet disposal criteria The O'Brien ampersand Gere Companies tested a scouring decontamination system on concrete and steel surfaces contaminated with radioactive and hazardous wastes under the sponsorship of Martin Marietta Energy Systems, Inc. (MMES) at DOE's K-25 former gaseous diffusion plant in Oak Ridge, Tennessee. The scouring system that O'Brien ampersand Gere Companies developed removes fixed radioactive and hazardous surface contamination, while leaving the surface intact. Blasting residuals are dissolved and treated using physical/chemical processes. Bench- and pilot-scale testing of the soda blasting system was conducted between December 1993 and September 1994 on surfaces contaminated with uranium, technetium, heavy metals, and PCBs. Areas of concrete and metal surfaces were blasted. Blasting residuals were dissolved in tap water and treated for radioactive, hazardous, and organochlorine constituents. The treatment system comprised pH adjustment, aeration, solids settling, filtration, carbon adsorption, and ion exchange. This system produced treated water and residual solid waste. Testing demonstrated that the system is capable of removing greater than 95% of radioactive and PCB surface contamination to below DOE's unrestricted use release limits; aqueous radionuclides, heavy metals, and PCBs were below DOE and USEPA treatment objectives after blasting residuals treatment. Waste residuals volume was decreased by 71%

  16. Staphylococcus aureus dry-surface biofilms are more resistant to heat treatment than traditional hydrated biofilms.

    Science.gov (United States)

    Almatroudi, A; Tahir, S; Hu, H; Chowdhury, D; Gosbell, I B; Jensen, S O; Whiteley, G S; Deva, A K; Glasbey, T; Vickery, K

    2018-02-01

    The importance of biofilms to clinical practice is being increasingly realized. Biofilm tolerance to antibiotics is well described but limited work has been conducted on the efficacy of heat disinfection and sterilization against biofilms. To test the susceptibility of planktonic, hydrated biofilm and dry-surface biofilm forms of Staphylococcus aureus, to dry-heat and wet-heat treatments. S. aureus was grown as both hydrated biofilm and dry-surface biofilm in the CDC biofilm generator. Biofilm was subjected to a range of temperatures in a hot-air oven (dry heat), water bath or autoclave (wet heat). Dry-surface biofilms remained culture positive even when treated with the harshest dry-heat condition of 100°C for 60min. Following autoclaving samples were culture negative but 62-74% of bacteria in dry-surface biofilms remained alive as demonstrated by live/dead staining and confocal microscopy. Dry-surface biofilms subjected to autoclaving at 121°C for up to 30min recovered and released planktonic cells. Recovery did not occur following autoclaving for longer or at 134°C, at least during the time-period tested. Hydrated biofilm recovered following dry-heat treatment up to 100°C for 10min but failed to recover following autoclaving despite the presence of 43-60% live cells as demonstrated by live/dead staining. S. aureus dry-surface biofilms are less susceptible to killing by dry heat and steam autoclaving than hydrated biofilms, which are less susceptible to heat treatment than planktonic suspensions. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  17. Changes in the surface roughness and friction coefficient of orthodontic bracket slots before and after treatment.

    Science.gov (United States)

    Liu, Xiaomo; Lin, Jiuxiang; Ding, Peng

    2013-01-01

    In this study, we tested the surface roughness of bracket slots and the friction coefficient between the bracket and the stainless steel archwire before and after orthodontic treatment. There were four experimental groups: groups 1 and 2 were 3M new and retrieved brackets, respectively, and groups 3 and 4 were BioQuick new and retrieved brackets, respectively. All retrieved brackets were taken from patients with the first premolar extraction and using sliding mechanics to close the extraction space. The surface roughness of specimens was evaluated using an optical interferometry profilometer, which is faster and nondestructive compared with a stylus profilometer, and provided a larger field, needing no sample preparation, compared with atomic force microscopy. Orthodontic treatment resulted in significant increases in surface roughness and coefficient of friction for both brands of brackets. However, there was no significant difference by brand for new or retrieved brackets. These retrieval analysis results highlight the necessity of reevaluating the properties and clinical behavior of brackets during treatment to make appropriate treatment decisions. © Wiley Periodicals, Inc.

  18. Reduction of a thin chromium oxide film on Inconel surface upon treatment with hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Vesel, Alenka, E-mail: alenka.vesel@guest.arnes.si [Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Mozetic, Miran [Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Balat-Pichelin, Marianne [PROMES-CNRS Laboratory, 7 Rue du four solaire, 66120 Font Romeu Odeillo (France)

    2016-11-30

    Highlights: • Oxidized Inconel alloy was exposed to hydrogen at temperatures up to 1500 K. • Oxide reduction in hydrogen plasma started at approximately 1300 K. • AES depth profiling revealed complete reduction of oxides in plasma. • Oxides were not reduced, if the sample was heated just in hydrogen atmosphere. • Surface of reduced Inconel preserved the same composition as the bulk material. - Abstract: Inconel samples with a surface oxide film composed of solely chromium oxide with a thickness of approximately 700 nm were exposed to low-pressure hydrogen plasma at elevated temperatures to determine the suitable parameters for reduction of the oxide film. The hydrogen pressure during treatment was set to 60 Pa. Plasma was created by a surfaguide microwave discharge in a quartz glass tube to allow for a high dissociation fraction of hydrogen molecules. Auger electron depth profiling (AES) was used to determine the decay of the oxygen in the surface film and X-ray diffraction (XRD) to measure structural modifications. During hydrogen plasma treatment, the oxidized Inconel samples were heated to elevated temperatures. The reduction of the oxide film started at temperatures of approximately 1300 K (considering the emissivity of 0.85) and the oxide was reduced in about 10 s of treatment as revealed by AES. The XRD showed sharper substrate peaks after the reduction. Samples treated in hydrogen atmosphere under the same conditions have not been reduced up to approximately 1500 K indicating usefulness of plasma treatment.

  19. Surface modification of porous poly(tetrafluoraethylene) film by a simple chemical oxidation treatment

    International Nuclear Information System (INIS)

    Wang Shifang; Li Juan; Suo Jinping; Luo Tianzhi

    2010-01-01

    A simple, inexpensive and environmental chemical treatment process, i.e., treating porous poly(tetrafluoroethylene) (PTFE) films by a mixture of potassium permanganate solution and nitric acid, was proposed to improve the hydrophilicity of PTFE. To evaluate the effectiveness of this strong oxidation treatment, contact angle measurement was performed. The effects of treatment time and temperature on the contact angle of PTFE were studied as well. The results showed that the chemical modification decreased contact angle of as-received PTFE film from 133 ± 3 deg. to 30 ± 4 deg. treated at 100 deg. C for 3 h, effectively converting the hydrophobic PTFE to a hydrophilic PTFE matrix. The changes in chemical structure, surface compositions and crystal structure of PTFE were examined by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), environmental scanning electron microscopy (ESEM), X-ray diffraction (XRD), respectively. It was found that the F/C atomic ratio decreased from untreated 1.65-0.10 treated by the mixture at 100 deg. C for 3 h. Hydrophilic groups such as carbonyl (C=O) and hydroxyl (-OH) were introduced on the surface of PTFE after treatment. Furthermore, hydrophilic compounds K 0.27 MnO 2 .0.54H 2 O was absorbed on the surface of porous PTFE film. Both the introduction of hydrophilic groups and absorption of hydrophilic compounds contribute to the significantly decreased contact angle of PTFE.

  20. Surface modification of cellulose acetate membrane using thermal annealing to enhance produced water treatment

    Science.gov (United States)

    Kusworo, T. D.; Aryanti, N.; Firdaus, M. M. H.; Sukmawati, H.

    2015-12-01

    This study is performed primarily to investigate the effect of surface modification of cellulose acetate using thermal annealing on the enhancement of membrane performance for produced water treatment. In this study, Cellulose Acetate membranes were casted using dry/wet phase inversion technique. The effect of additive and post-treatment using thermal annealing on the membrane surface were examined for produced water treatment. Therma annealing was subjected to membrane surface at 60 and 70 °C for 5, 10 and 15 second, respectively. Membrane characterizations were done using membrane flux and rejection with produced water as a feed, Scanning Electron Microscopy (SEM) and Fourier Transform Infra Red (FTIR) analysis. Experimental results showed that asymmetric cellulose acetate membrane can be made by dry/wet phase inversion technique. The results from the Scanning Electron Microscopy (FESEM) analysis was also confirmed that polyethylene glycol as additivie in dope solution and thermal annealing was affected the morphology and membrane performance for produced water treatment, respectively. Scanning electron microscopy micrographs showed that the selective layer and the substructure of membrane became denser and more compact after the thermal annealing processes. Therefore, membrane rejection was significantly increased while the flux was slighty decreased, respectively. The best membrane performance is obtained on the composition of 18 wt % cellulose acetate, poly ethylene glycol 5 wt% with thermal annealing at 70° C for 15 second.