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Sample records for espingarda kaolin deposit

  1. Bauxite and Kaolin Deposits of the Irwinton district, Georgia

    Science.gov (United States)

    Lang, Walter B.; Warren, Walter C.; Thompson, Raymond M.; Overstreet, Elizabeth F.

    1965-01-01

    The Irwinton district is in the central part of Georgia at the inner margin of the Coastal Plain province. The oldest rocks exposed in the district are crystalline rocks of the Piedmont province. They are unconformably overlain by nonmarine sedimentary strata of Late Cretaceous age, including gravel, micaceous sand, and lenses of kaolin. Bauxite has been found in a few of the kaolin lenses near the top of the sequence of these strata. During a long period prior to deposition of the over- lying marine beds of the Claiborne and Jackson Groups (middle and upper Eocene), the Upper Cretaceous strata were subjected to subaerial erosion. The bauxite deposits are considered to have formed during this period. They range in thickness from a few inches to more than 10 feet and occupy areas ranging from a few square feet to more than 5 acres. Most of the known bauxite deposits lie along the valleys of Commissioners Creek and Big Sandy Creek in Wilkinson County. The kaolin lenses are much larger than the bauxite deposits; some of the lenses underlie more than 200 acres and are more than 20 feet thick. Bauxite was discovered in the district in 1907 and was mined from 1910 to 1928. A few additional carloads of ore were shipped in 1941 and 1942, but no ore has been mined since that time. Reserves of high-grade bauxite are very small. Reserves of all grades of bauxite plus bauxitic clay may be about 400,000 long tons. The Irwinton district is the principal source of high-grade kaolin in the United States. The presence of kaolin here has been known since early colo- nial time, and it has been mined continuously since 1897. Production in 1959 was 1,940,279 short tons. The reserves of kaolin are very large but have never been adequately measured. Reserves of first and second grade kaolin may be 67 to 84 million short tons. Kaolin of lower grade is present in larger quantity.

  2. Kaolin

    Science.gov (United States)

    Virta, R.L.

    2013-01-01

    Nineteen companies mined kaolin in eight states in 2012. Production, on the basis of preliminary data, was estimated to be 5.88 Mt (6.48 million st) valued at $841 million, an increase from 5.77 Mt (6.36 million st) valued at $817 million in 2011. Production in Georgia, the top producing state, increased to an estimated 5.45 Mt (6.01 million st) valued at $804 million in 2012 from 5.34 Mt (5.89 million st) valued at $781 million in 2011. Georgia accounted for 93 percent of U.S. production tonnage and nearly the entire domestic water-washed, delaminated and pigment-grade calcined kaolin production.

  3. The contribution of lateritization processes to the formation of the kaolin deposits from eastern Amazon

    Science.gov (United States)

    da Costa, Marcondes Lima; Sousa, Daniel José Lima; Angélica, Rômulo Simões

    The eastern region of the Amazon is home to the most important kaolin bauxite producing district in Brazil, referred to as the Paragominas-Capim kaolin bauxite district, which has a reserve of at least 1.0 billion tons of high-quality kaolin used in the paper coating industry. The kaolin deposits are closely related to sedimentary rocks of the Parnaíba basin and their lateritic cover. Two large deposits are already being mined: IRCC (Ipixuna) and PPSA (Paragominas). The geology of the IRCC mine is comprised of the kaolin-bearing lower unit (truncated mature laterite succession derived from the Ipixuna/Itapecuru formation) and the upper unit (immature lateritized Barreiras formation). The lower kaolin unit is characterized by a sandy facies at the bottom and a soft (ore) with flint facies at the top. It is formed by kaolinite, quartz, some iron oxi-hydroxides, mica and several accessories and heavy minerals. The mangrove covering; and immature lateritization - partial kaolin ferruginization during the Pleistocene.

  4. Mineralogical association in the zone of argillic advanced alteration in a kaolin deposit of Patagonia Argentina

    International Nuclear Information System (INIS)

    Rainoldi, A; Oviedo, P.; Maiza, P.; Marfil, S.

    2010-01-01

    This work is about the mineralogical and petrological relations of the para genetic association of advanced argillic zone in the kaolin deposit in Patagonia.This study allowed to establish the sequence of events that took place in the deposit as well as the conditions under which they were generated

  5. Assessment of the adsorptive capacity of the Kaolin deposit targeting its use on the removal of colors in aqueous solution

    International Nuclear Information System (INIS)

    Matos, S.C.; Hildebrando, E.A.

    2016-01-01

    The Amazonic region has large and valuable kaolin deposits. The state of Para by itself comprises three large industries which process kaolin. It has been noticed that the waste resulting from the processing of kaolin is rich in silico-aluminate, presenting potential in adsorption processes. Thus, this research's objective is to assess the kaolin waste produced during the processing phase, aiming at its application as low cost adsorbent material. For that, the kaolin waste has been characterized by X-ray diffraction and chemical analysis (XRF), and then sieved and calcined at 700 ° C, being then subjected to the adsorption process and observed qualitatively its capacity of retention by methylene blue (AM). Preliminary results show that the kaolin waste has satisfactory adsorption capacity at concentrations of up to 50.0 mg / MP, demonstrating the potential that it be used in the removal of dyes in wastewater treatment. (author)

  6. Deposition of waste kaolin in aluminum alloy by electrolytic plasma technique

    International Nuclear Information System (INIS)

    Palinkas, Fabiola Bergamasco da Silva Marcondes; Antunes, Maria Lucia Pereira; Cruz, Nilson Cristino; Rangel, Elidiane Cipriano; Souza, Jose Antonio da Silva

    2016-01-01

    Full text: Kaolin is a widely explored mineral for various industrial purposes and its processing generates up to 90% of waste, corresponding to 500 thousand tons annually. The Deposition of Kaolin residue on aluminum alloys by electrolytic plasma has objective of a valorization of the residue. It was evaluated the mineralogical composition by X-ray diffraction (XRD), using PANalytical diffractometer X'Pert Pro. The scanning electron microscopy (SEM) and the spectrometry of dispersive of energy (EDS) evaluated the morphology and elementary chemical composition by microscope scanning electron JEOL JSM-6010LA. The Infrared Spectroscopy (FTIR) has used a Spectrometer the Perkin-Elmer 1760X FT-IR with spectral range 4000-400 cm -1 . XRD results indicate peaks of kaolinite as the main constituent. The morphology of the particles correspond to pseudo-hexagonal lamellar crystals characteristic of kaolinite, analysis by EDS allows to identify the composition of the particles as Al and Si. The samples were deposited at concentrations of 5, 10 and 15 mg of the residue and each concentration were considered deposition times of 5, 10 and 15 minutes. Tests evaluate the films as the wettability, chemical composition, morphology, mechanical strength and corrosion resistance. Results indicate the presence of kaolinite, alumina and mullite in the obtained coatings. (author)

  7. 1.7. Acid decomposition of kaolin clays of Ziddi Deposit. 1.7.1. The hydrochloric acid decomposition of kaolin clays and siallites

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Mirzoev, D.Kh.; Boboev, Kh.E.

    2016-01-01

    Present article of book is devoted to hydrochloric acid decomposition of kaolin clays and siallites. The chemical composition of kaolin clays and siallites was determined. The influence of temperature, process duration, acid concentration on hydrochloric acid decomposition of kaolin clays and siallites was studied. The optimal conditions of hydrochloric acid decomposition of kaolin clays and siallites were determined.

  8. Contemporary technology of enrichment of kaolins of Angren deposit. II. Removal of impurities and whitening of kaolins: using electrophysical and chemical methods of cleaning

    International Nuclear Information System (INIS)

    Krivorotov, V.F.; Usmanov, ZH.M.; Fridman, A.A.

    2012-01-01

    The contemporary methods of enrichment of Angren kaolins have been described. The electrophoresis and chemical whitening are demonstrated to be the most effective methods of scavenging. Application of ultrasonic dispersion, electrophoresis and chemical whitening methods allows one to obtain kaolin with whiteness ≅ 88% and content of iron oxides ≅ 0.4%. Using such kaolin as a sorbent at de coloration of plant oil have been shown good adsorption properties, meeting the level of world-wide standards for such class of materials. (authors)

  9. Feasible synthesis of TiO2 deposited on kaolin for photocatalytic applications

    Czech Academy of Sciences Publication Activity Database

    Henych, Jiří; Štengl, Václav

    2013-01-01

    Roč. 61, 3-4 (2013), s. 165-176 ISSN 0009-8604 R&D Projects: GA MPO FR-TI1/006 Institutional support: RVO:61388980 Keywords : Homogeneous Hydrolysis * Kaolin * Photocatalysis * TiO2 * Urea Subject RIV: CA - Inorganic Chemistry Impact factor: 1.398, year: 2013

  10. Contemporary technology of enrichment of Angren deposit of kaolins. I. Using a ultrasonic dispersion for shallowing of raw materials

    International Nuclear Information System (INIS)

    Krivorotov, V.F.; Usmanov, Zh.M.; Fridman, A.A.

    2012-01-01

    Optimal parameters of ultrasonic dispersion at enrichment of Angren kaolins are presented. It has been stated that the granule sizes of the kaolin-powder produced by this technology are 0.15-4.0 μm, and 75% of particles have sizes 0.15-1.5 μm. The whiteness of the kaolin-powder amounts 80 - 82%. (authors)

  11. Assessment of the adsorptive capacity of the Kaolin deposit targeting its use on the removal of colors in aqueous solution; Avaliacao da capacidade adsortiva do rejeito de caulim visando seu uso na remocao de corantes em solucao aquosa

    Energy Technology Data Exchange (ETDEWEB)

    Matos, S.C.; Hildebrando, E.A., E-mail: matos.cintia68@gmail.com [Universidade Federal do Para (FEMat/UFPA), PA (Brazil). Faculdade de Engenharia de Materiais

    2016-07-01

    The Amazonic region has large and valuable kaolin deposits. The state of Para by itself comprises three large industries which process kaolin. It has been noticed that the waste resulting from the processing of kaolin is rich in silico-aluminate, presenting potential in adsorption processes. Thus, this research's objective is to assess the kaolin waste produced during the processing phase, aiming at its application as low cost adsorbent material. For that, the kaolin waste has been characterized by X-ray diffraction and chemical analysis (XRF), and then sieved and calcined at 700 ° C, being then subjected to the adsorption process and observed qualitatively its capacity of retention by methylene blue (AM). Preliminary results show that the kaolin waste has satisfactory adsorption capacity at concentrations of up to 50.0 mg / MP, demonstrating the potential that it be used in the removal of dyes in wastewater treatment. (author)

  12. A Mexican kaolin deposit: XANES characterization, mineralogical phase analysis and applications

    Directory of Open Access Journals (Sweden)

    Martínez, A.

    2009-06-01

    Full Text Available A kaolin obtained from Villa de Reyes, a region near to San Luis Potosí (México was characterized by means of X-ray powder diffraction (XRD, optical microscopy (OM, scanning electron microscopy (SEM, X-ray fluorescence (XRF, X-Ray Absorption Near Edge Spectroscopy (XANES, thermal analysis (DTA/TGA, dilatometry (DIL, and chemical analysis. Mineralogical and morphological characteristics of the mineral are presented. The kaolin sample was formed mainly by kaolinite, but other minor phases were also detected such as quartz, cristobalite, tridymite, and dolomite. The high content of volcanic glass detected, by optical microscopy, revealed an incomplete kaolinization process of the raw material. The reddish color of the kaolin was associated with the free iron content in the form of limonite [FeO(OH], which was determined by XANES. The influence of the particle size on the whiteness of kaolin was evaluated. Dilatometric analysis revealed a strong thermal expansion between 110 y 240 °C, which would difficult the use of this material in traditional ceramic applications. On the other hand the presence of glass and high temperature phases of SiO2, such as cristobalite and tridymite will favor its use in the cement industry.El caolín obtenido de Villa de Reyes, una región cercana a San Luis Potosí, México, fue caracterizado por las siguientes técnicas: difracción de rayos-X en polvos (DRX, microscopía óptica (MO, microscopía electrónica de barrido (MEB, fluorescencia de rayos-X (FRX, espectroscopía de absorción de rayos-X (XANES, análisis térmico (DTA/TGA, dilatometría (DIL y análisis químico. Los resultados del análisis mineralógico mediante DRX mostraron un mineral constituido principalmente de caolinita, con una contribución minoritaria de cuarzo, cristobalita, tridimita y dolomita. El análisis por microscopía óptica reveló un alto contenido de material amorfo volcánico, indicando una caolinización incompleta del material v

  13. Behaviour of major, minor and trace elements (including REEs during kaolinization processes at Zonouz deposit, northeast of Marand, East Azarbaidjan province

    Directory of Open Access Journals (Sweden)

    Vahideh Alipour

    2011-11-01

    Full Text Available The Zonouz kaolin deposit is located ~15 km northeast of Marand, East-Azarbaidjan province. Based on physical features in field investigations, such as color, five distinct kaolin types including (1 white, (2 lemon, (3 gray, (4 brown, and (5 yellow are distinguished in the deposit. Field evidence and petrographic studies indicate that the deposit is genetically close to trachy-andesite rocks. According to mineralogical data, the deposit contains quartz, kaolinite, montmorillonite, calcite, pyrophyllite, chlorite, muscovite-illite, dolomite, hematite, and anatase minerals. Geochemical data indicate that function of alteration processes on trachy-andesite rocks during development of Zonouz ore deposit was accompanied by leaching of elements such as Al, Na, K, Rb, Ba, V, Hf, Cu, Zr, Tm, Yb, and Lu, enrichment of elements such as U, Nb, and Ta, and leaching-fixation of elements such as Si, Fe, Ca, Mg, Ti, Mn, P, Cs, Sr, Th, Co, Cr, Ni, Y, Ga, LREE, Tb, Dy, Ho, and Er. Incorporation of obtained results from mineralogical and geochemical studies show that physico-chemical conditions of alteration environment, the relative stability of primary minerals, surface adsorption, preferential sorption by metallic oxides, existing of organic matters, scavenging and concentration processes, and fixation in neomorphic mineralogical phases played important role in distribution of elements in the deposit. Geochemical studies show that development of the deposit is relative to two types of processes, (1 hypogene and (2 supergene. The distribution pattern of REEs indicates that differentiation degree of LREEs from HREEs in supergene kaolins is more than hypogene kaolins. Geochemical studies indicate that minerals such as Mn-oxides, zircon, anatase, hematite, cerianite, and secondary phosphates (monazite, rhabdophane, churchite, and zenotime are the potential hosts for rare earth elements in this deposit.

  14. Characterization and Evaluation of a kaolin deposit located in Los Azufres Michoacan, Mexico, for Industrial Use

    International Nuclear Information System (INIS)

    Guillen, J.; Bribiesca, S.; Escudero, R.

    2012-01-01

    In this work a kaolin ore from the region of Los Azufres, state of Michoacan, Mexico, was characterized and evaluated in order to assess its use in the industry. A powder fraction less than 45 μm were studied by X-ray fluorescence (XRF), x-ray diffraction (XRD) and infrared spectroscopy (IR). The results showed high silica content of ∼70%, associated with minerals such as cristobalite, tridimite and quartz followed by kaolinite and a small amount of alunite. The distribution, morphology and surface area of the particles were obtained by Laser Diffraction, Scanning Electron Microscopy (SEM) and Brunauer Emmett Teller technique (BET). Thermal characterization was performed by differential thermal analysis (DTA), thermal gravimetric analysis (TGA) and dilatometric analysis. The thermal characterization results displayed a strong mineral thermal expansion from room temperature to 300 degree centigrade, followed by an abrupt contraction a temperatures between 580 degree centigrade to 920 degree. This could be associated with phase transformations of the polymorph of silica, the dehydroxylation of the alunite and kaolinite and the desulfatation of alunite. The physical properties such as mineral color, degree of whiteness, plasticity, linear shrinkage and density were also determined. Finally whit the results obtained in this work, it can be concluded that the investigated ore is highly recommended for the cement industry and plastic. (Author) 29 refs.

  15. Heavy mineral as a tool to refine the stratigraphy of kaolin deposits in the Rio Capim Area, Northern Brazil

    Directory of Open Access Journals (Sweden)

    Ana M. Góes

    2007-09-01

    Full Text Available Studies of heavy minerals in kaolin deposits from the Ipixuna Formation in the Rio Capim area (Northern Brazil showed a mature to super mature assemblage dominated by zircon and tourmaline, and subordinately rutile, kyanite and staurolite. These minerals do not change much throughout the whole section; however, each kaolin unit displays a particular signature, defined by differences in the proportions of the whole assemblage of heavy minerals, as well as of their textural characteristics. This work revealed that the lower and upper kaolin units can be definitely considered as distinct depositional sequences. A higher proportion of opaque minerals and higher zircon values characterize the lower unit. The higher volumes of anhedric, rounded to sub-rounded grains of zircon and tourmaline in the upper unit suggests that this includes grains that were undergone to a higher degree of reworking. The increased volume of unaltered staurolite and kyanite in the upper unit leads to conclude that, even considering sediment reworking, a distinct source must be invoked. The results also show that the characteristics of the heavy mineral assemblage from the intermediate unit are comparable with those from the upper unit, which suggests they might record a same stratigraphic sequence.Estudos de minerais pesados provenientes em depósitos cauliníticos da Formação Ipixuna na região do rio Capim (Brasil revelaram uma mineralogia matura a supermatura, representada dominantemente por zircão e turmalina e, subordinadamente, rutilo, cianita e estaurolita. Os minerais encontrados não variam muito, entretanto cada unidade caulinítica apresenta uma assinatura particular definida por diferenças nasproporções entre os principais minerais, assim como em suas características texturais. Este trabalho demonstrou que asunidades de caulim soft (inferior e semi-flint (superior podem ser consideradas seqüências deposicionais distintas. As altas percentagens de opacos

  16. Associated minerals and their influence on the optical properties of jordanian kaolin

    International Nuclear Information System (INIS)

    Awwad, A. M.; Ahmad, R.; Alsyouri, H.

    2009-01-01

    Kaolin samples from AL-Disi kaolin deposits in southeastren of Jordan are associated with mineral impurities, wich impart color to this kaolin and adverseely affect its application in paper and paint industries. The associated mineral impurities with kaolin were separated by deflocculating particles in polymeric sodium polyphosphate solution. The crude kaolin, deflocculated kaolin (suspended kaolin), and the associated mineral impurities with kaolin (residue) were determined by X-ray flourescence, X-ray diffraction, FTIR spectroscopy, and spectroscopic studies. The composition of the residue separated from Al-Disi kaolin composed mainaly from quartz, feldspar, and hematite. The separation of these associated mineral impurities from al-Disi kaolin by deflocculating process improves the brightness of kaolin to be suitable for processing to produce kaolin that meets specifications for paper making, filler, cosmetics and other uses that demand high whiteness and low impurity content . (authors).

  17. Os paratextos editoriais em “Alabardas, Alabardas, Espingardas, Espingardas”, o romance inacabado de José Saramago

    Directory of Open Access Journals (Sweden)

    Bianca Rosina Mattia

    2016-12-01

    Full Text Available Em 2014, quatro anos após a morte de José Saramago, chegava às livrarias seu último romance, que restou inacabado e foi encontrado em seu computador. Alabardas, alabardas, Espingardas, espingardas tem apenas três capítulos. Porém, a edição do livro apresenta ainda o diário de Saramago, com anotações referentes ao romance, ilustrações de Günter Grass e textos de outros autores. O romance centra-se na temática da violência, da guerra e da fabricação e comércio de armas. Neste artigo, contudo, objetivamos uma análise dos paratextos editoriais da edição de Alabardas. A proposta, nesse sentido, pauta-se, a partir da definição de paratexto apresentada por Gérard Genette (2009, na investigação de uma possibilidade de leitura de Alabardas não [só] como romance, mas como manifesto. Tal possibilidade alicerça-se no caráter polissêmico dos paratextos editoriais, que proporcionam novas perspectivas de leitura e interferem na produção de sentidos quando da leitura do texto, bem como na concepção de editor enquanto adaptador, considerando um dos conceitos de adaptação abordados por Linda Hutcheon (2013.

  18. Tough and Reinforced Polypropylene/Kaolin Composites using Modified Kaolin

    Science.gov (United States)

    Yao, J. L.; Zhu, H. X.; Qi, Y. B.; Guo, M. J.; Hu, Q.; Gao, L.

    2018-05-01

    Polypropylene (PP)/kaolin composites have been prepared by filling modified kaolin with diethylenetriaminepentaacetic acid (DTPA) into the PP matrix. The surface modification of kaolin particles effectively improves the compatibility between kaolin and PP matrix. It is conducive for uniform dispersion of inorganic particles in the matrix, and enhances the mechanical performance of the composites. Compared with plain kaolin, the mechanical properties of the modified composites exhibit higher tensile strength, bending strength, impact strength and melt index simultaneously. The DTPA modification of kaolin overall enhances the mechanical properties of PP composites. It meets the requirements in various applications, and makes the modified experiment interesting in modern teaching.

  19. Chemical treatment of kaolin. Case study of kaolin from the Tamazert– Jijel mine

    Directory of Open Access Journals (Sweden)

    Mohamed Chouafa

    2016-01-01

    Full Text Available The Tamazert-Jijel kaolin deposit is located in eastern Algeria, It was formed during a process of hydro-thermal alteration of feldspars rich in potassium. Kaolin, obtained at the mine, mainly contains varying amounts of impurities such as iron oxide (Fe2O3 and anatase (TiO2. These components negatively affect the quality of the commercial product. This research was performed to improve the quality of kaolin to be used in the paper industry with the goal of reducing the impurities of iron and titanium oxides. Different sized fractions of the original sample were analyzed by XRD. The results obtained showed that the mineralogical composition is: quartz, muscovite, kaolinite, dolomite, albite and orthoclase. Kaolin, like all clays, has a thin dissemination of minerals throughout it. After processing kaolin, the particle size fraction of less than 45μm, corresponding to the liberation mesh size, was retained for purification by chemical treatment with different acids of different concentrations (hydrochloric acid, sulfuric acid, acetic acid, heated to boiling point temperatures. The kaolin samples treated with the various acids above were analyzed by X-ray fluorescence and by XRD. The results obtained from the sample treated with hydrochloric acid show that the iron oxide content of acid is reduced by 1.65% to 0.88%. Meanwhile, the brightness of the sample reached 90% under the effect of the treatment with hydrochloric acid at concentration of 2 mole/dm3.

  20. The hydrogen isotopic composition of kaolin minerals in Japan

    International Nuclear Information System (INIS)

    Marumo, Katsumi; Nagasawa, Keinosuke; Kuroda, Yoshimasu.

    1979-01-01

    Hydrogen isotopic composition (D/H ratio) was determined for kaolin minerals from geothermal areas and sedimentary and hydrothermal kaolin deposits in Japan. On the Ohnuma, Matsukawa, and Ohtake geothermal areas, the hydrogen isotopic fractionation factor between kaolin minerals and water was calculated to fall between 0.97 and 0.99 for the temperature range of 50 to 200 0 C, a fact which shows that the temperature of formation has no important effect on the D/H ratio of kaolin minerals. D/H ratio of kaolinites and dickites from many kaolin deposits shows local variation, and seems to correlate with isotopic variation of the present-day meteoric surface water. Exceptions are seen in some kaolin deposits such as Shokozan, Hiroshima Prefecture, where kaolinite and dickite have considerably high values of D/H ratio, and seem to have reacted with water rich in deuterium. D/H ratio of halloysite is not correlated with that of the present-day meteoric surface water. As Lawrence and Taylor (1971) pointed out, the original D/H ratio of constitutional water of halloysite is not preserved because of the isotopic exchange between the interlayer water and the constitutional water. (author)

  1. Geochemistry of Selected Kaolins from Cameroon and Nigeria

    Directory of Open Access Journals (Sweden)

    Bukalo Nenita N.

    2017-12-01

    Full Text Available The geochemical characteristics of selected kaolins from Cameroon and Nigeria are presented, with an attempt to elucidate on their possible industrial applications by comparing them to world-known kaolin deposits. Major oxides concentrations were subjected to factor analyses in interpreting their relationships. Geochemical indices, including chemical index of alteration (CIA, chemical index of weathering (CIW and the index of compositional variability (ICV were computed and plotted on binary and ternary diagrams to determine the intensity of weathering of the kaolins and discriminate their different source rock types. Kaolinite was the major phase, followed by quartz, illite and goethite as minor phases. Minerals in trace phases included smectite, anatase, muscovite, gibbsite, microcline, palygorskite and calcite. Mean abundances of major oxides in wt% were: SiO2 (56.96>Al2O3 (24.09>Fe2O3 (3.78>TiO2 (1.53> K2O (1.26> MgO (0.27>CaO (0.20>Na2O (0.17>P2O5 (0.05>MnO (0.04. The CIW versus CIA and ICV versus CIA plots showed that most of the kaolins clearly depicted extreme silicate weathering. The current applications of kaolins from Cameroon and Nigeria include ceramics and manufacturing of bricks and tiles. Low MgO, CaO, Na2O, K2O and TiO2 further position the kaolins for pharmaceutics, cosmetics, rubber and plastic applications. Thus, the studied kaolins have the potential to contribute to improved economic development of these countries.

  2. Geochemistry of Selected Kaolins from Cameroon and Nigeria

    Science.gov (United States)

    Bukalo, Nenita N.; Ekosse, Georges-Ivo E.; Odiyo, John O.; Ogola, Jason S.

    2017-12-01

    The geochemical characteristics of selected kaolins from Cameroon and Nigeria are presented, with an attempt to elucidate on their possible industrial applications by comparing them to world-known kaolin deposits. Major oxides concentrations were subjected to factor analyses in interpreting their relationships. Geochemical indices, including chemical index of alteration (CIA), chemical index of weathering (CIW) and the index of compositional variability (ICV) were computed and plotted on binary and ternary diagrams to determine the intensity of weathering of the kaolins and discriminate their different source rock types. Kaolinite was the major phase, followed by quartz, illite and goethite as minor phases. Minerals in trace phases included smectite, anatase, muscovite, gibbsite, microcline, palygorskite and calcite. Mean abundances of major oxides in wt% were: SiO2 (56.96)>Al2O3 (24.09)>Fe2O3 (3.78)>TiO2 (1.53)> K2O (1.26)> MgO (0.27)>CaO (0.20)>Na2O (0.17)>P2O5 (0.05)>MnO (0.04). The CIW versus CIA and ICV versus CIA plots showed that most of the kaolins clearly depicted extreme silicate weathering. The current applications of kaolins from Cameroon and Nigeria include ceramics and manufacturing of bricks and tiles. Low MgO, CaO, Na2O, K2O and TiO2 further position the kaolins for pharmaceutics, cosmetics, rubber and plastic applications. Thus, the studied kaolins have the potential to contribute to improved economic development of these countries.

  3. CERAMIC PROPERTIES OF PUGU KAOLIN CLAYS. PART 2 ...

    African Journals Online (AJOL)

    a

    PART 2: EFFECT OF PHASE COMPOSITION ON FLEXURAL STRENGTH ... working in this field have established factors controlling the various ... The raw materials selected were kaolin clays from Pugu deposit in Tanzania, Norfloat potash .... the total mullite contents present in the samples since the method used does.

  4. Method removing radioactivity from kaolin

    International Nuclear Information System (INIS)

    Conley, R.F.

    1978-01-01

    A method of reducing the radioactivity found in naturally occurring kaolins to about 40% below its native value, and the leachable radiogenic components to less than 20% is described. This reduction is achieved by removing from the kaolin particles of a size less than 0.5 microns. This removal may be carried out by gravitational settling, flocculation of non-colloidal particles, or acid leaching

  5. Kaolin from Acoculco (Puebla, Mexico) as a raw material: mineralogical and thermal characterization

    OpenAIRE

    Garcia Vallès, Maite; Pi, T.; Alfonso, P.; Canet, C.; Martínez Manent, Salvador; Jiménez-Franco, A.; Tarragó Aymerich, Mariona; Hernández-Cruz, B.

    2015-01-01

    The present study determined the mineralogy and thermal properties of kaolin from Acoculco (Puebla), at the eastern Trans-Mexican Volcanic Belt and compared it with the nearby deposits of Agua Blanca (Hidalgo) and Huayacocotla (Veracruz). The mineralogy of the kaolins was determined by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. Thermal behaviour was studied by differential thermal analysis, dilatometry and hot-stage microscopy. The Acoculco deposit is composed ...

  6. 21 CFR 186.1256 - Clay (kaolin).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Clay (kaolin). 186.1256 Section 186.1256 Food and... Substances Affirmed as GRAS § 186.1256 Clay (kaolin). (a) Clay (kaolin) Al2O3.2SiO2.nH2O, Cas Reg. No. 1332-58-7) consists of hydrated aluminum silicate. The commercial products of clay (kaolin) contain...

  7. Use of airborne gamma-ray spectrometry for kaolin exploration

    Science.gov (United States)

    Tourlière, B.; Perrin, J.; Le Berre, P.; Pasquet, J. F.

    2003-08-01

    Airborne gamma-ray spectrometry was used to define targets with kaolin potential in the Armorican Massif of Brittany, France. This exploration method is based on the principle that kaolinite, an aluminosilicate clay mineral constituting kaolin, is formed by the hydrolysis of potash feldspar with the elimination of potassium. Therefore, potassium contrast between favourable host-rock such as a leucogranite and kaolin occurrence is likely a significant pathfinder. As the relationship between the potassium-40 recorded by an airborne gamma-ray spectrometer and total potassium is constant, such data provide us a direct measurement of the potassium content of the ground flown over. Our study tested this by calculating, for each geological unit, the difference between the measured and average potassium content calculated for a given geological formation. The study was based on (i) a recent (1998) high-definition airborne geophysical survey over the Armorican Massif undertaken on behalf of the French Government, and (ii) new geological compilation maps covering the same region. Depleted zones, where the measured potassium is less than the average potassium content calculated target areas with high potential of containing kaolin, provided that the unit was originally rich in potash feldspar. By applying this method to the entire Armorican Massif, it was possible to identify 150 potassium-depleted zones, including 115 that were subjected to rapid field checks and 36 that contained kaolin (21 new discoveries). This method, which is both safe for the environment and easy to use, is therefore a good tool for rapidly defining targets with kaolin potential at a regional scale. The method may also have possibilities in exploring for other types of deposit characterised by an enrichment or depletion in U, K and/or Th.

  8. Fluoride retention by kaolin clay

    DEFF Research Database (Denmark)

    Kau, P. M. H.; Smith, D. W.; Binning, Philip John

    1997-01-01

    To evaluate the potential effectiveness of kaolin clay liners in storage of fluoride contaminated waste, an experimental study of the sorption and desorption behaviour of fluoride in kaolin clay was conducted. The degree of fluoride sorption by kaolin was found to depend on solution p......H and available fluoride concentration with equilibrium being achieved within 24 h. A site activation process involving the uptake of fluoride was also observed at the initial stages of sorption. This behaviour was attributed to a layer expansion process of the clay during sorption. The maximum fluoride sorption...... capacity was found to be 18.3 meq/100 g at pH 6 and 8.6 meq/100 g at pH 7. A competitive Langmuir sorption isotherm where sorption is dependant on both pH and fluoride concentration is employed to characterise the experimental sorption and desorption data. The sorption and desorption isotherms revealed...

  9. Assembling strategy to synthesize palladium modified kaolin nanocomposites with different morphologies

    Science.gov (United States)

    Li, Xiaoyu; Ouyang, Jing; Zhou, Yonghua; Yang, Huaming

    2015-09-01

    Nanocomposites of aluminosilicate minerals, kaolins (kaolinite and halloysite) with natural different morphologies assembling with palladium (Pd) nanoparticles have been successfully synthesized through strong electrostatic adsorption and chemical bonding after surface modification with 3-aminopropyl triethoxysilane (APTES). Meanwhile, the influence of different morphologies supports on catalytic hydrogenation properties was explored. The surface concentration of amino groups on the kaolins was related to the morphology and surface nature. Electronmicroscopy revealed that the monodisperse Pd nanoparticles were uniformly deposited onto the surface of kaolins, ranging in diameter from 0.5 nm to 5.5 nm. The functional groups could not only improve the dispersion of kaolins with different morphologies in solution, but also enhance the interaction between Pd precursors and kaolins, thus preventing small Pd nanoparticles from agglomerating and leading to high activity for the catalytic hydrogenation of styrene. Pd-FK@APTES was more active compared to other samples. Selecting the kaolin morphology with a different surface nature allows the selective surface modification of a larger fraction of the reactive facets on which the active sites can be enriched and tuned. This desirable surface coordination of catalytically active atoms could substantially improve catalytic activity.

  10. Nitrate Adsorption on Clay Kaolin: Batch Tests

    Directory of Open Access Journals (Sweden)

    Morteza Mohsenipour

    2015-01-01

    Full Text Available Soils possessing kaolin, gibbsite, goethite, and hematite particles have been found to have a natural capacity to attenuate pollution in aqueous phase. On the other hand, the hydroxyl group in soil increases anion exchange capacity under a low pH condition. The main objective of this paper was to evaluate effects of kaolin on nitrate reduction under acidic condition. In order to analyze the kaolin adsorption behaviour under various conditions, four different concentrations of nitrate, 45, 112.5, 225, and 450 mgNO3-/L, with a constant pH equal to 2, constant temperature equal to 25°C, and exposure period varying from 0 to 150 minutes were considered. The capacity of nitrate adsorption on kaolin has also been studied involving two well-known adsorption isotherm models, namely, Freundlich and Longmuir. The results revealed that approximately 25% of the nitrate present in the solution was adsorbed on clay kaolin. The laboratory experimental data revealed that Freundlich adsorption isotherm model was more accurate than Longmuir adsorption model in predicting of nitrate adsorption. Furthermore, the retardation factor of nitrate pollution in saturated zone has been found to be approximately 4 in presence of kaolin, which indicated that kaolin can be used for natural scavenger of pollution in the environment.

  11. Technological properties of kaolin from Para

    International Nuclear Information System (INIS)

    Hildebrando, E.; Martin-Cortes, G.R.; Esper, F.J.; Wiebeck, H.; Alves Junior, P.; Valenzuela-Diaz, F.R.

    2011-01-01

    The NE of the State of Para, is notable for its large reserves of kaolin for paper. Kaolin is a mineral composed of hydrated aluminum silicates such as kaolinite and halloysite. The exploitation of these reserves to generate products with higher commercial value, especially in the industries of adsorbents and catalysts, is what motivates the continuous study of technological properties of the Amazon kaolin's. Thus, this paper presents a technological characterization of a sample of kaolin from Para State by X-ray diffraction, SEM - scanning electron microscopy and infrared spectroscopy. The results of preliminary tests indicate that the sample consists for the most part by kaolinite present in low concentrations of quartz and anatase. (author)

  12. Entrained Flow Reactor Test of Potassium Capture by Kaolin

    DEFF Research Database (Denmark)

    Wang, Guoliang; Jensen, Peter Arendt; Wu, Hao

    2015-01-01

    In the present study a method to simulate the reaction between gaseous KCl and kaolin at suspension fired condition was developed using a pilot-scale entrained flow reactor (EFR). Kaolin was injected into the EFR for primary test of this method. By adding kaolin, KCl can effectively be captured...

  13. Infrared detection of the mineralogical aspects that influence the processing of calcined kaolin

    Science.gov (United States)

    Groenheide, Stefan; Guatame-Garcia, Adriana; Buxton, Mike; van der Werff, Harald

    2017-04-01

    Calcined kaolin is an industrial minerals product used in the production of paper, paint, rubber and other specialty applications. It is produced from kaolinite through a series of refinement steps and final calcination at temperatures of above 900°C, with the aim of generating a whiter and more abrasive material. The raw kaolin ore is a mixture of clay minerals, quartz and feldspars, where kaolinite is the main constituent. The optimal kaolin ores to feed the processing plant should ideally have high kaolinite abundance, be free in Fe-bearing mineralogy (to avoid influence in the colour of the product), and the kaolinite itself should be of high crystallinity (to ensure the correct abrasiveness after calcination). This work presents a case study from the kaolin deposits in the St. Austell Granite (South-West England), which are known for their high quality and world-class size. In this area, the kaolin is of primary-hydrothermal origin, with mineral associations that are related to the genetic history. The eventual depletion of the high-quality reserves is bringing now the attention to the lower grade zones, where the amount of impurities increases. As a consequence, it is critical to developing strategies that ensure the supply of high-quality ore to the processing plant. For this, it is necessary to acquire a thorough knowledge of the ore, including relative abundance of the minerals and their textural relationships. Hyperspectral images in the visible-near infrared (VNIR) and short-wave infrared (SWIR) ranges were collected from drill cores and run-off-mine (ROM) samples, obtained from one of the kaolin pits in the St. Austell area, where the kaolin quality is known to be lower than in the rest of the deposit. A series of mineral maps were generated to assess the distribution, texture and abundance of the Fe-bearing mineralogy and the other kaolin-associated minerals, as well as the variations in the crystallinity of kaolinite. The mineral maps enabled the

  14. Geology and industrial mineral resources of the Macon-Gordon Kaolin District, Georgia

    Science.gov (United States)

    Buie, Bennett Frank; Hetrick, J.H.; Patterson, S.H.; Neeley, C.L.

    1979-01-01

    The Macon-Gordon kaolin district is about 80 miles (130 km) southeast of Atlanta, Georgia. It extends across the boundary between, and includes parts of, the Piedmont and Atlantic Coastal Plain physiographic provinces. The rocks in the Piedmont are mainly intensely folded sericite schist and granite gneiss containing irregular masses of amphibolite and feldspathic biotite gneiss and scattered igneous intrusive rocks. Most of the crystalline rocks are thought to be of Paleozoic age, but some of the intrusive rocks may be younger. The crystalline rocks are cut by a major unconformity and are overlain by sedimentary formations ranging in age from Cretaceous to Miocene. The valuable kaolin deposits occur in the Cretaceous beds, undivided, and in the Huber Formation which is of Paleocene to middle Eocene age. The resources of kaolin in the district are estimated in millions of metric tons as follows: reserves, 100; subeconomic resources, 700 to 900; undiscovered resources, probably 700 to 1,000. In addition to kaolin, the leading mineral commodity mined in the district, crushed stone and sand are now being produced, and fuller's earth and a minor amount of limestone were formerly produced. The crushed stone is quarried from igneous rocks in the Piedmont province. The sand is washed from the Cretaceous beds, undivided. The fuller's earth was mined from the Twiggs Clay Member of the Barnwell Formation, and limestone was dug from the Tivola Limestone.

  15. Gravimetric and conductometric studies of the sedimentation kinetics in aqueous dispersions of kaoline

    International Nuclear Information System (INIS)

    Bulavyin, L.A.; Khrapatij, S.V.; Koval'chuk, V.Yi.; Klepko, V.V.; Lebovka, M.Yi.

    2006-01-01

    Using gravimetric and conductometric methods, the sedimentation kinetics in aqueous suspensions of Alekseev kaoline has been studied for pH value range from 4 to 10. It has been found that pH increasing leads to the decreasing of mean radii of flocks linearly. We found that sedimentation kinetics for intermediate pH values can be described by scaling equations that crossover time defined transition from a gravitational mechanism of deposition to the diffusion one

  16. Rheological and Thermal Behavior of Polypropylene-Kaolin Composites

    International Nuclear Information System (INIS)

    Teng, S.T.; Nor Azura Abdul Rahim; Lan, D.N.U

    2014-01-01

    Kaolins effect on rheological behaviour of polypropylene-kaolin composites was investigated. The research found that not only the kaolin content influence the rheological behaviour but also the compounding using internal mixer and twin screw extruder. In details, viscosity and shear stress increased with addition of kaolin content. These characteristics also exhibited higher in polypropylene-kaolin composite suspensions compounded using twin screw extruder than using internal mixer. Chain scission was assumed to occur and affect the melt properties. Further justification characterized by Differential Scanning Calorimeter (DSC) showed that the effect of kaolin and loading content were more evident on the onset melting temperature and crystallinity. Besides, due to the different cooling operation in both processes, the effect of compounding on melting characteristic was conspicuous. (author)

  17. Potassium Capture by Kaolin, Part 1: KOH

    DEFF Research Database (Denmark)

    Wang, Guoliang; Jensen, Peter Arendt; Wu, Hao

    2018-01-01

    -capture level. The effect of reaction temperature,K-concentration in the flue gas, and, thereby, molar ratio of K/(Al+Si) in reactants, gas residence time, and solid particle size on K-capture reaction was systematically investigated. Corresponding equilibrium calculations were conducted with FactSage 7.......0. The experimental results showed that kaolin reached almost full conversion to K-aluminosilicates under suspension-fired conditions at 1100–1450 °C for a residence time of 1.2 s and a particle size of D50 = 5.47 μm. The amount of potassium captured by kaolin generally followed the equilibrium at temperatures above...

  18. Physical properties and chemical composition of Segamat Kaolin, Johor, Malaysia

    International Nuclear Information System (INIS)

    Umar Hamzah; Learn, K.K.; Sahibin Rahim

    2010-01-01

    Kaolin is a source of secondary mineral as a product of a weathering process of primary minerals. Its main component is fine grain kaolinite (< 2 μm) and it also contains other elements such as aluminium and iron phyllosilicate as the pigment. Aluminium rich kaolin is light in colour with high plasticity and is normally used in the ceramic, plastic, paint, paper, pesticide, pharmacology and cosmetic industries. The physical and chemical characteristics of kaolins are important for its potential application. In this study, about 25 kaolin samples were hand-augered from depths of 1-2 m at Buloh Kasap Segamat, Johor, Malaysia. Chemical analysis carried out included determination of oxides and types of minerals by X-ray diffraction and X-ray fluorescence. Shrinkage rate, rupture modulus and water absorption rate tests were carried out in the physical properties analysis. Plastic and liquid limits of the kaolin were also measured for plastic index. The Segamat kaolin was light in colour due to its high silicate composition. The highest mineral content in the kaolin was kaolinite and quartz occurred as impurities. The low shrinkage rate showed that the kaolin was dense with little voids, hence very suitable for use in the ceramic industry. This kaolin has low water absorption, plasticity and durable according to the rupture modulus test. (author)

  19. Removal of Phenol in Aqueous Solution Using Kaolin Mineral Clay

    International Nuclear Information System (INIS)

    Sayed, M.S.

    2008-01-01

    Kaolin clay were tested for phenol removal as toxic liquid waste from aqueous waste water. Several experimental conditions such as weight and particle size of clay were investigated to study batch kinetic techniques, also the ph and concentration of the phenol solution were carried out. The stability of the Langmuir adsorption model of the equilibrium data were studied for phenol sorbent clay system. Infrared spectra, thermogravimetric and differential thermal analysis techniques were used to characterize the behavior of kaolin clay and kaolin clay saturated with phenol. The results obtained showed that kaolin clay could be used successfully as an efficient sorbent material to remove phenol from aqueous solution

  20. XANES at the silicon k-edge in the kaolin-meta kaolin-geopolymer system

    International Nuclear Information System (INIS)

    Lima, F.T.; Silva, F.J.; Thaumaturgo, C.

    2005-01-01

    The geo polymer synthesis process optimization pretends to control the re logical and mechanical properties. The Al/Si ratio is the main variable that governs the geo polymerization process. This control occurs by changing temperature, pressure and chemical composition of the geo polymer. Thermal analysis (DTA/DSC), microscopic (SEM/TEM) and spectroscopic (FTIR, XRD, SAXS, EXAFS and XANES) techniques have been used to characterize these inorganic systems. In this work, XANES spectra of the k-edge silicon (Si) of the kaolin-meta kaolin-geo polymer are presented. The XANES spectra provides the oxidation state and structural information about the present studied atom: Silicon (Si). (author)

  1. Performance of Kaolin Clay on the Concrete Pavement

    Science.gov (United States)

    Abdullah, M. E.; Jaya, R. P.; Shahafuddin, M. N. A.; Yaacob, H.; Ibrahim, M. H. Wan; Nazri, F. M.; Ramli, N. I.; Mohammed, A. A.

    2018-05-01

    This paper investigates the performance of concrete pavement containing kaolin clay with their engineering properties and to determine the optimum kaolin clay content. The concrete used throughout the study was designed as grade 30 MPa strength with constant water to cement ratio of 0.49. The compressive strength, flexural strength and water absorption test was conducted in this research. The concrete mix designed with kaolin clay as cement replacement comprises at 0%, 5%, 10% and 15% by the total weight of cement. The results indicate that the strength of pavement concrete decreases as the percentage of kaolin clay increases. It also shows that the water absorption increases with the percentage of cement replacement. However, 5% kaolin clay is found to be the optimum level to replace cement in a pavement concrete.

  2. Sintering mechanism of blast furnace slag-kaolin ceramics

    International Nuclear Information System (INIS)

    Mostafa, Nasser Y.; Shaltout, Abdallah A.; Abdel-Aal, Mohamed S.; El-maghraby, A.

    2010-01-01

    A general ceramics processing scheme by cold uniaxial pressing and conventional sintering process have been used to prepare ceramics from mixtures of blast furnace slag (BFS) and kaolin (10%, 30% and 50% kaolin). The properties of the ceramics were studied by measuring linear shrinkage, bulk density, apparent porosity and mechanical properties of samples heated at temperatures from 800 o C to 1100 o C. The formed crystalline phases were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM). Slag melt formed at relatively low temperatures (800-900 o C) modified the sintering process to liquid phase sintering mechanism. Combination of BFS with 10% kaolin gave the highest mechanical properties, densification and shrinkage at relatively low firing temperatures. The crystalline phases were identified as gehlenite (Ca 2 Al 2 SiO 7 ) in both BFS and BFS with 10% kaolin samples. Anorthite (CaAl 2 Si 2 O 8 ) phase increased with increasing kaolin contents. In the case of kaolin-rich mixtures (30% and 50% kaolin), increased expansion took place during firing at temperatures in the range 800-1000 o C. This effect could be attributed to the entrapment of released gases.

  3. Synthesis of microporous material faujasite-type from kaolin waste

    International Nuclear Information System (INIS)

    Hildebrando, E.A.; Valenzuela-Diaz, F.R.; Angelica, R.S.; Neves, R.F.

    2010-01-01

    Zeolite with structure faujasite was synthesized using kaolin waste from kaolin processing industries for paper coating as predominant source of silicon and aluminum; the starting material was characterized by XRF, XRD, DTA/TG, SEM, and products obtained by XRD and SEM. Synthesis in hydrothermal conditions occurred on autoclave and time-temperature effects, as well as the relationship Si/Al were considered. The results show that the methodology developed with the waste of calcined kaolin reacting at 90 deg C for 20 hours in an alkaline medium, in the presence of an additional source of silica was obtained zeolite Y as single phase present in the product. (author)

  4. Effect of kaolin particle size and loading on the characteristics of kaolin ceramic support prepared via phase inversion technique

    Directory of Open Access Journals (Sweden)

    Siti Khadijah Hubadillah

    2016-06-01

    Full Text Available In this study, low cost ceramic supports were prepared from kaolin via phase inversion technique with two kaolin particle sizes, which are 0.04–0.6 μm (denoted as type A and 10–15 μm (denoted as type B, at different kaolin contents ranging from 14 to 39 wt.%, sintered at 1200 °C. The effect of kaolin particle sizes as well as kaolin contents on membrane structure, pore size distribution, porosity, mechanical strength, surface roughness and gas permeation of the support were investigated. The support was prepared using kaolin type A induced asymmetric structure by combining macroporous voids and sponge-like structure in the support with pore size of 0.38 μm and 1.05 μm, respectively, and exhibited ideal porosity (27.7%, great mechanical strength (98.9 MPa and excellent gas permeation. Preliminary study shows that the kaolin ceramic support in this work is potential to gas separation application at lower cost.

  5. ADSORPTION OF PARAQUAT DICHLORIDE TO KAOLIN PARTICLES AND TO MIXTURES OF KAOLIN AND HEMATITE PARTICLES

    Directory of Open Access Journals (Sweden)

    Dina Alexandra Martins

    2015-03-01

    Full Text Available Deliberate contamination with pesticides is a potential risk to water security, due to the availability of these contaminants and the fact that they do not need special expertise to handle or apply. Adsorption of the herbicide paraquat from an aqueous solution to suspended particles of kaolin and kaolin/hematite mixture was investigated by kinetic and equilibrium assays, taking into consideration several parameters such as initial pH, sorbent dosage and agitation speed. The results showed that the adsorption process is quite fast, reaching an 18% reduction in paraquat concentration in a very short period of time. The addition of hematite particles to kaolin suspension had no apparent effect on the maximum amount of paraquat adsorbed. Kinetic parameters were determined by fitting the pseudo-second order model to the experimental data (correlation coefficients close to 1. Isotherm studies indicate an inhibitory effect, promoted by hematite particles, that was not detected in the adsorption assays. Equilibrium data was best adjusted using the Langmuir model which yielded higher correlation coefficient values and smaller normalized standard deviations.

  6. Caulins brasileiros: alguns aspectos da geologia e da mineralogia Brazilian kaolins: some aspects of the geology and mineralogy

    Directory of Open Access Journals (Sweden)

    Ian Richard Wilson

    1998-08-01

    , kaolin derived from pegmatite, from granitic rocks, from volcanic rocks and kaolin derived from anorthosite. The sedimentary clays are mainly found in the Amazon basin and those adjacent to the Jari River are being exploited commercially for export as a paper coating clay. Amazon kaolin is characterised by high iron and titania (lattice-held with low levels of alkali and exhibiting euhedral kaolinite crystals. The South-eastern pegmatite, when not iron stained, are extremely low in iron and titania and a mixture of kaolinite 7Å/10Å-halloysite occurs in all deposits. The North-eastern pegmatite produces kaolin constituted only by euhedral kaolinites with an absence of halloysite. Kaolin from granites generally has higher iron levels when compared with pegmatite and deposits constituted only by kaolinite are rare, a mixture of kaolinite/7Å-halloysite being common. Both the pegmatite and granite derived kaolin are utilised as a paper filler and in general ceramics. Volcanic rocks on alteration produce a fine siliceous clay with titania levels higher than other types and are generally mixtures of kaolinite-7Å. Volcanic derived clays are utilized locally in ceramics. Kaolins derived from anorthosite are similar in iron and titania levels to those from granitic kaolins. Assemblages of kaolinite and small quantities of 7Å-halloysite are found. These clays are used in both whiteware ceramics and paper filler.

  7. Flocculation of kaolin and lignin by bovine blood and hemoglobin

    Science.gov (United States)

    Polymeric flocculants are used extensively for water purification, inhibition of soil erosion, and reduction in water leakage from unlined canals. Production of highly active, renewable polymeric flocculants to replace synthetic flocculants is a priority. Using suspensions of kaolin, flocculation ...

  8. Electrical Properties of Zinc-Kaolin Composites below its Percolation ...

    African Journals Online (AJOL)

    In this paper, we present some electrical properties of the zinc-kaolin cermet resistors with zinc metal fillers below the percolation threshold. Rectangular cermet rods of dimensions 65 mm by 6.5 mm by 3.2 mm were produced in a mould with semi-dry the zinc/kaolin powder mixture which is compressed with a force of about ...

  9. Shear Strength of Stabilized Kaolin Soil Using Liquid Polymer

    Science.gov (United States)

    Azhar, A. T. S.; Fazlina, M. I. S.; Nizam, Z. M.; Fairus, Y. M.; Hakimi, M. N. A.; Riduan, Y.; Faizal, P.

    2017-08-01

    The purpose of this research is to investigate the suitability of polymer in soil stabilization by examining its strength to withstand compressive strength. Throughout this research study, manufactured polymer was used as a chemical liquid soil stabilizer. The liquid polymer was diluted using a proposed dilution factor of 1 : 3 (1 part polymer: 3 parts distilled water) to preserve the workability of the polymer in kaolin mixture. A mold with a diameter of 50 mm and a height of 100 mm was prepared. Kaolin soil was mixed with different percentages of polymer from 10%, 15%, 20%, 25%, 30% and 35% of the mass of the kaolin clay sample. Kaolin mixtures were tested after a curing period of 3 days, 7 days, 14 days and 28 days respectively. The physical properties were determined by conducting a moisture content test and Atterberg limit test which comprise of liquid limit, plastic limit and shrinkage limit. Meanwhile, the mechanical properties of the soil shear strength were identified through an unconfined compressive strength (UCS) test. Stabilized kaolin soil showed the highest compressive strength value when it was mixed with 35% of polymer compared to other percentages that marked an increment in strength which are 45.72% (3 days), 67.57% (7 days), 81.73% (14 days) and 77.84% (28 days). Hence, the most effective percentage of liquid polymer which should be used to increase the strength of kaolin soil is 35%.

  10. Rheological properties of kaolin and chemically simulated waste

    International Nuclear Information System (INIS)

    Selby, C.L.

    1981-12-01

    The Savannah River Laboratory is conducting tests to determine the best operating conditions of pumps used to transfer insoluble radioactive sludges from old to new waste tanks. Because it is not feasible to conduct these tests with real or chemically simulated sludges, kaolin clay is being used as a stand-in for the solid waste. The rheology tests described herein were conducted to determine whether the properties of kaolin were sufficiently similar to those of real sludge to permit meaningful pump tests. The rheology study showed that kaolin can be substituted for real waste to accurately determine pump performance. Once adequately sheared, kaolin properties were found to remain constant. Test results determined that kaolin should not be allowed to settle more than two weeks between pump tests. Water or supernate from the waste tanks can be used to dilute sludge on an equal volume basis because they identically affect the rheological properties of sludge. It was further found that the fluid properties of kaolin and waste are insensitive to temperature

  11. Characterization of kaolin wastes from kaolin mining industry from the amazon region as raw material for pozzolans production

    International Nuclear Information System (INIS)

    Barata, M.S.; Angelica, R.S.

    2012-01-01

    Capim and Jari are the two most important kaolin mining districts of the Brazilian Amazon region. They encompass the major Brazilian reserves of high quality kaolin for the paper coating industry. The kaolin is mined and processed by three major companies responsible for about 500,000 ton of a residue mainly composed of kaolinite. The wastes come mainly from the centrifugation phase of the kaolin beneficiation process and their final destinations are huge sedimentation basins that occupy large areas. The main purpose of this work is to evaluate the physical, chemical and mineralogical characteristics of the kaolin wastes processed from the Capim and Jari region, in order to obtain meta kaolinite, a high reactive pozzolans for the cement industry. When incorporated to ordinary Portland cement such pozzolans increases the concrete and mortars performance. All the residues studied in this work were characterized by means of: X-ray diffraction analysis, differential thermal analysis, infrared spectroscopy, scanning electron microscopy, X-ray fluorescence spectrometry and laser diffraction. Both residues are mainly constitutes by at least 92% of low granulometry kaolinite with specific surface area above 8 m2 /g and mean diameter below 1 μm. Free silica (quartz) contents are below 3%. The high concentration of kaolinite in these residues dispenses rigid control parameters for removal of impurities usually employed in pozzolans production. The Jari kaolin exhibits high disordered kaolinite in comparison with the high ordered kaolinite of the Capim region and gives rise to higher desidroxilation degree at lower temperatures. It points to energy saving and reducing costs during the production of a pozzolans. The results are satisfactory and reveal that both kaolin wastes are excellent raw material for the production of high reactive meta kaolin. (author)

  12. Uranium in mining water of kaolin open pit in Zarów (Lower Silesia); methodology of determination and genetic remarks.

    Science.gov (United States)

    Chau, N D; Wyszomirski, P; Chruściel, E; Ochoński, A

    1999-11-01

    In this paper, a method of determination of uranium 238 and 234 in mining waters of Andrzej kaolin open pit in Zarów (Lower Silesia) is presented. The method is based on independent measurements of alpha and beta radiation intensities by means of a liquid scintillation spectrometer alpha/beta. The initial volume of water sample was 3 dm3, then it was diminished by chemical preparation to 6 cm3, and then 12 cm3 of scintillator was added. The lower limit of detection (for the measurement time of 8 h) for both 234U and 238U amounted to 0.02 Bq/dm3. For determination of the uranium content in ferruginous sediments precipitating from mining waters of the above-mentioned open pit, gamma ray spectrometry was used. The obtained results may be viewed as a contribution to studies on anomalous uranium concentration within this kaolin deposit. The elevated uranium content, in comparison with its average concentration in the Earth crust, is characteristic for parent rocks of Andrzej kaolin deposit, which are granitoids of Strzegom-Sobótka massif. In connection with it, the high uranium content can be observed not only in kaolin and weakly kaolinised granitoids from the deposit in question, but also in mining waters genetically related with them.

  13. 1.7.2. The hydrochloric acid decomposition of pre-baked kaolin clays and siallites

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.; Mirzoev, D.Kh.; Boboev, Kh.E.

    2016-01-01

    Present article of book is devoted to hydrochloric acid decomposition of pre-baked kaolin clays and siallites. The chemical composition of kaolin clays and siallites was determined. The influence of temperature, process duration, acid concentration on hydrochloric acid decomposition of pre-baked kaolin clays and siallites was studied. The optimal conditions of hydrochloric acid decomposition of pre-baked kaolin clays and siallites were determined.

  14. Bio-beneficiation of kaolin and feldspar and its effect on fired

    Indian Academy of Sciences (India)

    Presence of iron compounds as impurities in kaolin and feldspar, impart reddish colour to ceramic products manufactured using these minerals. The quality of kaolin and feldspar was enriched mainly through iron removal by biological methods. Bacteria isolated from kaolin of Indian origin were used for bioleaching.

  15. Production and Structural Investigation of Polyethylene Composites with Modified Kaolin

    International Nuclear Information System (INIS)

    Domka, L.; Malicka, A.; Stachowiak, N.

    2008-01-01

    The study was undertaken to evaluate the effect of the filler (kaolin) modification with silane coupling agents on the properties of the polyethylene (HDPE Hostalen ACP 5831) composites. Powder mineral fillers are added to polymers to modify the properties of the latter and to reduce the cost of their production. A very important factor is the filler dispersion in the polymer matrix. Kaolin modified with 3-methacryloxypropyltrimethoxysilane and pure kaolin were characterised by surface area, pore size, water absorbing capacity, paraffin oil absorbing capacity, bulk density, scanning electron microscopy observations and X-ray diffraction measurements. Their performance was characterised by determination of the mechanical resistance upon static stretching and tearing, and their structure was observed in scanning electron microscopy images. The results were compared to those obtained for the composites with unmodified filler and pure HDPE. (authors)

  16. Production and Structural Investigation of Polyethylene Composites with Modified Kaolin

    Science.gov (United States)

    Domka, L.; Malicka, A.; Stachowiak, N.

    2008-08-01

    The study was undertaken to evaluate the effect of the filler (kaolin) modification with silane coupling agents on the properties of the polyethylene (HDPE Hostalen ACP 5831) composites. Powder mineral fillers are added to polymers to modify the properties of the latter and to reduce the cost of their production. A very important factor is the filler dispersion in the polymer matrix. Kaolin modified with 3-methacryloxypropyltrimethoxysilane and pure kaolin were characterised by surface area, pore size, water absorbing capacity, paraffin oil absorbing capacity, bulk density, scanning electron microscopy observations and X-ray diffraction measurements. Their performance was characterised by determination of the mechanical resistance upon static stretching and tearing, and their structure was observed in scanning electron microscopy images. The results were compared to those obtained for the composites with unmodified filler and pure HDPE.

  17. Kaolin Quality Prediction from Samples: A Bayesian Network Approach

    International Nuclear Information System (INIS)

    Rivas, T.; Taboada, J.; Ordonez, C.; Matias, J. M.

    2009-01-01

    We describe the results of an expert system applied to the evaluation of samples of kaolin for industrial use in paper or ceramic manufacture. Different machine learning techniques - classification trees, support vector machines and Bayesian networks - were applied with the aim of evaluating and comparing their interpretability and prediction capacities. The predictive capacity of these models for the samples analyzed was highly satisfactory, both for ceramic quality and paper quality. However, Bayesian networks generally proved to be the most useful technique for our study, as this approach combines good predictive capacity with excellent interpretability of the kaolin quality structure, as it graphically represents relationships between variables and facilitates what-if analyses.

  18. Effects of Dietary Kaolin Supplementation on the Growth ...

    African Journals Online (AJOL)

    One hundred and sixty (160) Anak 2000 day-old broiler chicks were used to investigate the effects of kaolin on the haematology and growth performance of broilers. The chicks were randomly assigned to four treatments, each treatment consisting of four pens with 10 chicks per pen. The four treatments were; basal diet only ...

  19. Physicochemical Evaluation of Industrial Potentialities of Getso Kaolin

    African Journals Online (AJOL)

    2017-08-13

    Aug 13, 2017 ... manufacturing sector. In this study kaolin from Getso, Kano state, northern part of Nigeria was characterized ... foreign import, leaving a supply gap of over. 250,000 .... the presence of mica; the strong band at 3694 cm-1. 80.53.

  20. Synthesis of Gamma-Alumina from Kankara Kaolin as Potential ...

    African Journals Online (AJOL)

    In compounded zeolite catalyst it serves as the active matrix which aids the conversion of the bulkiest molecules in the feed owing to its larger pore size than zeolite. Large specific surface area gamma-alumina (γ-Al2O3) was synthesized by hydrothermal method using Kankara kaolin as starting material. Thermal treatment ...

  1. Synthesis of Gamma-Alumina from Kankara Kaolin as Potential ...

    African Journals Online (AJOL)

    Engr Solomn Gajere

    Large specific surface area gamma-alumina (γ-Al2O3) was synthesized by hydrothermal method using Kankara kaolin as starting material. Thermal treatment of ammonium alum prepared from the filtrate of the dealuminated metakaolin was employed to obtain the alumina. Crystalline aluminum sulfate with 39 wt% Al2O3 ...

  2. Structure and properties of pregelatinized cassava starch/kaolin composites

    International Nuclear Information System (INIS)

    Kaewtatip, Kaewta; Tanrattanakul, Varaporn

    2012-01-01

    Highlights: ► Pregelatinized starch/kaolin composites were prepared using compression molding. ► The tensile strengths of the composites were higher than for thermoplastic starch. ► Degradation temperatures of the composites were higher than for thermoplastic starch. ► The retrogradation behavior of the composites was hindered by kaolin. -- Abstract: Pregelatinized cassava starch/kaolin composites were prepared using compression molding. The morphology of the fractured surfaces, retrogradation behavior, thermal decomposition temperatures and mechanical properties of the composites were investigated using scanning election microscopy (SEM), X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and tensile testing, respectively. The tensile strengths and thermal degradation temperatures of the composites were higher than for thermoplastic starch (TPS). The retrogradation behavior of the composites was hindered by kaolin. The water absorption was measured after aging for 12 and 45 days at a relative humidity (RH) of 15% and 55%. It indicated that all the composites displayed lower water absorption values than TPS.

  3. Composite pigments based on surface coated kaolin and metakaolin

    Czech Academy of Sciences Publication Activity Database

    Štengl, Václav; Popelková, Daniela; Matys Grygar, Tomáš

    2014-01-01

    Roč. 101, NOV (2014), s. 149-158 ISSN 0169-1317 R&D Projects: GA MPO FR-TI1/006 Institutional support: RVO:61388980 Keywords : Kaolin * Homogeneous hydrolysis * Thioacetamide * Urea * Mullite * Metakaolin Subject RIV: CA - Inorganic Chemistry Impact factor: 2.467, year: 2014

  4. Electrical Properties of Zinc-Kaolin Composites below its Percolation ...

    African Journals Online (AJOL)

    Bheema

    In this paper, we present some electrical properties of the zinc-kaolin cermet resistors ..... The temperature coefficient of resistance of a material is generally defined as .... Characterisation and morphological Studies of palladium modified carbon ... conduction and microstructural properties of semiconducting Co-doped TiO2.

  5. Adsorption characteristics of brilliant green dye on kaolin

    International Nuclear Information System (INIS)

    Nandi, B.K.; Goswami, A.; Purkait, M.K.

    2009-01-01

    Experimental investigations were carried out to adsorb toxic brilliant green dye from aqueous medium using kaolin as an adsorbent. Characterization of kaolin is done by measuring: (i) particle size distribution using particle size analyzer, (ii) BET surface area using BET surface analyzer, and (iii) structural analysis using X-ray diffractometer. The effects of initial dye concentration, contact time, kaolin dose, stirring speed, pH and temperature were studied for the adsorption of brilliant green in batch mode. Adsorption experiments indicate that the extent of adsorption is strongly dependent on pH of solution. Free energy of adsorption (ΔG 0 ), enthalpy (ΔH 0 ) and entropy (ΔS 0 ) changes are calculated to know the nature of adsorption. The calculated values of ΔG 0 at 299 K and 323 K indicate that the adsorption process is spontaneous. The estimated values of ΔH 0 and ΔS 0 both show the negative sign, which indicate that the adsorption process is exothermic and the dye molecules are organized on the kaolin surface in less randomly fashion than in solution. The adsorption kinetic has been described by first-order, pseudo-second-order and intra-particle-diffusion models. It was observed that the rate of dye adsorption follows pseudo-second-order model for the dye concentration range studied in the present case. Standard adsorption isotherms were used to fit the experimental equilibrium data. It was found that the adsorption of brilliant green on kaolin follows the Langmuir adsorption isotherm

  6. PENGARUH METODE AKTIVASI PADA KEMAMPUAN KAOLIN SEBAGAI ADSORBEN BESI (FE AIR SUMUR GARUDA

    Directory of Open Access Journals (Sweden)

    Tirta Indah Wulan Sari

    2016-10-01

    Full Text Available Kaolin is a mineral found in sedimentary rocks known as clay stone. Kaolin widely applied in industries such as paper, ceramics, rubber, plastics, paint, glassfiber, and cosmetics. This study aimed to determine the effect on the ability of kaolin activation methods as adsorbent. The study was conducted by activation of kaolin in physics, chemistry, and chemistry-physics. Physical activation was done by heating kaolin at 700 ° C in a furnace for 30 minutes and for the chemical activation, the addition of 0.25 M HCl in kaolin with stirring speed of 200 rpm for 60 minutes, while the chemical-physical activation, the addition of 0.25 M HCl to the kaolin and continued warming in furnace at 700 ° C. The kaolin activation was to produce an adsorbent that is able to absorb iron (Fe optimally. From this study, the optimum activation obtained for kaolin in adsorbing Fe is the chemical activation. Chemical activated kaolin adsorbent having a large adsorption capacity of the ion Fe which resulted in decreased content of iron (Fe to 0.04 mg / L.

  7. Application Of Bacterial Iron Reduction For The Removal Of Iron Impurities From Industrial Silica Sand And Kaolin

    Science.gov (United States)

    Zegeye, A.; Yahaya, S.; Fialips, C. I.; White, M.; Manning, D. A.; Gray, N.

    2008-12-01

    Biogeochemical evidence exists to support the potential importance of crystalline or amorphous Fe minerals as electron acceptor for Fe reducing bacteria in soils and subsurface sediments. This microbial metabolic activity can be exploited as alternative method in different industrial applications. For instance, the removal of ferric iron impurities from minerals for the glass and paper industries currently rely on physical and chemical treatments having substantial economical and environmental disadvantages. The ability to remove iron by other means, such as bacterial iron reduction, may reduce costs, allow lower grade material to be mined, and improve the efficiency of mineral processing. Kaolin clay and silica sand are used in a wide range of industrial applications, particularly in paper, ceramics and glass manufacturing. Depending on the geological conditions of deposition, they are often associated with iron (hydr)oxides that are either adsorbed to the mineral surfaces or admixed as separate iron bearing minerals. In this study, we have examined the Fe(III) removal efficiency from kaolin and silica sand by a series of iron- reducing bacteria from the Shewanella species (S. alga BrY, S. oneidensis MR-1, S. putrefaciens CN32 and S. putrefaciens ATCC 8071) in the presence of anthraquinone 2,6 disulfonate (AQDS). We have also investigated the effectiveness of a natural organic matter, extracted with the silica sand, as a substitute to AQDS for enhancing Fe(III) reduction kinetics. The microbial reduction of Fe(III) was achieved using batch cultures under non-growth conditions. The rate and the extent of Fe(III) reduction was monitored as a function of the initial Fe(III) content, Shewanella species and temperature. The bacterially- treated minerals were analyzed by transmission electron microscopy (TEM) and X-ray diffraction (XRD) to observe any textural and mineralogical transformation. The whiteness and ISO brightness of the kaolin was also measured by

  8. Merger of waste in kaolin panels medium density

    International Nuclear Information System (INIS)

    Bezerra, A.F.C.; Santana, L.N.L.; Neves, G.A.

    2011-01-01

    Medium-density panels are molded under pressure and temperature and have physical and mechanical properties similar to those of solid wood. Their composition involves fibers of eucalyptus and pine, but other residues as kaolin waste can be incorporated. The objective was to manufacture medium density panels incorporating kaolin waste and compare the physical, chemical and mechanical properties of these with other commercials. The residue was subjected to the following characterization tests: X-ray diffraction, chemical analysis, differential thermal analysis, thermal gravimetric analysis and size analysis.Through the process of pressing the samples were prepared, they were evaluated for their flexural strength and tensile strength perpendicular to the water absorption / swelling in thickness, density and moisture content. According to the analyzed results, we conclude that samples having the residue had lower levels of swelling, tensile and flexural strength and higher levels of absorption.(author)

  9. Characterization of kaolin dispersion using acoustic and electroacoustic spectroscopy

    OpenAIRE

    Dohnalová Ž.; Svoboda L.; Šulcová P.

    2008-01-01

    The objective of this work is the investigation of the kaolin dispersion by the ultrasonic techniques. In contact with aqueous solution clay minerals show cation - exchange properties and certain degree of dissolution or rather selective leaching of components. The work is divided into two main parts - determination of zeta potential and particle size distribution. The first part is focused on measuring of zeta potential. Effects of concentration of solid, different kind of electrolytes (0.01...

  10. Preparation and Characterization of Acid and Alkaline Treated Kaolin Clay

    Directory of Open Access Journals (Sweden)

    Sachin Kumar

    2013-06-01

    Full Text Available Kaolin was refluxed with HNO3, HCl, H3PO4, CH3COOH, and NaOH of 3M concentration at 110 °C for 4 hours followed by calcination at 550 °C for 2 hours. The physico-chemical characteristics of resulted leached kaolinite clay were studied by XRF, XRD, FTIR, TGA, DTA, SEM and N2 adsorption techniques. XRF and FTIR study indicate that acid treatment under reflux conditions lead to the removal of the octahedral Al3+ cations along with other impurities. XRD of acid treated clay shows that, the peak intensity was found to decrease. Extent of leaching of Al3+ ions is different for different acid/base treatment. The acid treatment increased the Si/Al ratio, surface area and pore volume of the clay. Thus, the treated kaolin clay can be used as promising adsorbent and catalyst supports. © 2013 BCREC UNDIP. All rights reservedReceived: 1st March 2013; Revised: 9th April 2013; Accepted: 19th April 2013[How to Cite: Kumar, S., Panda, A. K., Singh, R.K. (2013. Preparation and Characterization of Acids and Alkali Treated Kaolin Clay. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 61-69. (doi:10.9767/bcrec.8.1.4530.61-69][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4530.61-69] |View in  |

  11. Statistical treatment of bleaching kaolin by iron removal

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez H, R. A.; Legorreta G, F.; Hernandez C, L. E. [Universidad Autonoma del Estado de Hidalgo, Area Academica de Ciencias de la Tierra y Materiales, Carretera Pachuca-Tulancingo Km 4.5, Mineral de la Reforma, 42184 Hidalgo (Mexico); Martinez L, A., E-mail: angelitofox3@hotmail.com [Universidad Autonoma de Coahuila, Blvd. V. Carranza y Gonzalez Lobo s/n, 25280 Saltillo, Coahuila (Mexico)

    2013-07-01

    In the present study, oxalic acid was used as a leaching reagent to remove iron from a kaolin mineral. Statistical analysis was conducted to determine the most influential factors in the dissolution of iron from the kaolin mineral. Our goal was ferric iron solubilization and its reduction to ferrous iron to improve the iron removal in the acid medium. Leaching experiments were conducted at atmospheric pressure. A two-level factorial design of the type 2{sup 4} was utilized. The dependent variable was the percentage of dissolved iron, and the dependent variables in this study were acid concentration (0.35 and 0.50 M), temperature (75 C and 100 C), leaching time (2 and 4 h), and ph (1.5 and 2.5). An analysis of variance revealed that the effects of the factors temperature (b), ph (d), and the combined effects of temperature and time (b c) resulted in the maximum dissolution of iron of 88% at 100 C, giving a kaolin mineral with a whiteness index 93.50. For the mineralogical analysis the X-ray diffraction technique was used. (Author)

  12. Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

    Directory of Open Access Journals (Sweden)

    Youngmin Choi

    2016-12-01

    Full Text Available Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°. Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material.

  13. Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

    Science.gov (United States)

    Choi, Youngmin; Choo, Hyunwook; Yun, Tae Sup; Lee, Changho; Lee, Woojin

    2016-01-01

    Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO) ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°). Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material. PMID:28774098

  14. Characterization of kaolin dispersion using acoustic and electroacoustic spectroscopy

    Directory of Open Access Journals (Sweden)

    Dohnalová Ž.

    2008-01-01

    Full Text Available The objective of this work is the investigation of the kaolin dispersion by the ultrasonic techniques. In contact with aqueous solution clay minerals show cation - exchange properties and certain degree of dissolution or rather selective leaching of components. The work is divided into two main parts - determination of zeta potential and particle size distribution. The first part is focused on measuring of zeta potential. Effects of concentration of solid, different kind of electrolytes (0.01 M KCl, 0.01 M MgCl2 and 0.01 M CaCl2, pH and temperature of the dispersions are investigated. The isoelectric points (IEP of kaolin suspension are about pH 4-5. Electrolytes containing monovalent cations such as K+ become zeta potential more negative compared to the values obtained with water. Such behavior is explained by the exchange of K+ ions with H+ ions in the system. When the electrolyte is formed by divalent cations such as Mg2+ or Ca2+, the values of zeta potential become less negative than zeta potential of kaolin in water. The second part is focused on the determination of particle size distribution with respect to dispersing conditions, such as the optimal dispersing agent (Na2SiO3, (NaPO36, Na4P2O7 or Busperse, time and power of ultrasonication and also the tracking of dispersion stability that is expressed by the measuring of particle size distribution during certain time period.

  15. Statistical treatment of bleaching kaolin by iron removal

    International Nuclear Information System (INIS)

    Hernandez H, R. A.; Legorreta G, F.; Hernandez C, L. E.; Martinez L, A.

    2013-01-01

    In the present study, oxalic acid was used as a leaching reagent to remove iron from a kaolin mineral. Statistical analysis was conducted to determine the most influential factors in the dissolution of iron from the kaolin mineral. Our goal was ferric iron solubilization and its reduction to ferrous iron to improve the iron removal in the acid medium. Leaching experiments were conducted at atmospheric pressure. A two-level factorial design of the type 2 4 was utilized. The dependent variable was the percentage of dissolved iron, and the dependent variables in this study were acid concentration (0.35 and 0.50 M), temperature (75 C and 100 C), leaching time (2 and 4 h), and ph (1.5 and 2.5). An analysis of variance revealed that the effects of the factors temperature (b), ph (d), and the combined effects of temperature and time (b c) resulted in the maximum dissolution of iron of 88% at 100 C, giving a kaolin mineral with a whiteness index 93.50. For the mineralogical analysis the X-ray diffraction technique was used. (Author)

  16. Surface modification of calcined kaolin with toluene diisocyanate based on high energy ball milling

    International Nuclear Information System (INIS)

    Yuan, Yongbing; Chen, Hongling; Lin, Jinbin; Ji, Yan

    2013-01-01

    The surface of calcined kaolin particle was modified with toluene diisocyanate (TDI) by using high energy ball milling. The prepared hybrids were characterized by FT-IR, MAS NMR, thermal analysis (TGA-DSC), static water contact angle (CA), apparent viscosity and transmission electron microscopy (TEM). FT-IR and MAS NMR spectra demonstrated that TDI molecules were chemically anchored to kaolin surface after modification. The results of thermal analysis showed that the maximum grafting ratio reached up to 446.61% when the mass ratio of TDI/kaolin was 0.5:1.0, and CA measurements revealed that the resultant hybrids exhibited strong hydrophobicity (148.82°). Apparent viscosity and TEM were employed to examine the dispersion properties of blank and modified kaolin particles in poly (dimenthylsiloxane) matrix. The results illustrated that the dispersion stability depended strongly on the grafting ratio of TDI, neither too low nor too high achieved uniform and stable dispersion, and the favorable grafting ratio was obtained when the mass ratio of TDI/kaolin was 0.2:1.0. Further modification of TDI/kaolin (mass ration of TDI/kaolin, 1.0:1.0) particles with bis(aminopropyl)-terminated-poly(dimethylsiloxane) (APS) was also investigated. TEM evidenced that the dispersion properties of the obtained TDI/APS/kaolin particles were remarkably improved in octamethyl cyclotetrasiloxane compared with the original TDI/kaolin particles.

  17. Surface modification of calcined kaolin with toluene diisocyanate based on high energy ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Yongbing; Chen, Hongling, E-mail: hlchen@njut.edu.cn; Lin, Jinbin; Ji, Yan

    2013-11-01

    The surface of calcined kaolin particle was modified with toluene diisocyanate (TDI) by using high energy ball milling. The prepared hybrids were characterized by FT-IR, MAS NMR, thermal analysis (TGA-DSC), static water contact angle (CA), apparent viscosity and transmission electron microscopy (TEM). FT-IR and MAS NMR spectra demonstrated that TDI molecules were chemically anchored to kaolin surface after modification. The results of thermal analysis showed that the maximum grafting ratio reached up to 446.61% when the mass ratio of TDI/kaolin was 0.5:1.0, and CA measurements revealed that the resultant hybrids exhibited strong hydrophobicity (148.82°). Apparent viscosity and TEM were employed to examine the dispersion properties of blank and modified kaolin particles in poly (dimenthylsiloxane) matrix. The results illustrated that the dispersion stability depended strongly on the grafting ratio of TDI, neither too low nor too high achieved uniform and stable dispersion, and the favorable grafting ratio was obtained when the mass ratio of TDI/kaolin was 0.2:1.0. Further modification of TDI/kaolin (mass ration of TDI/kaolin, 1.0:1.0) particles with bis(aminopropyl)-terminated-poly(dimethylsiloxane) (APS) was also investigated. TEM evidenced that the dispersion properties of the obtained TDI/APS/kaolin particles were remarkably improved in octamethyl cyclotetrasiloxane compared with the original TDI/kaolin particles.

  18. Influence of Sulfonated-Kaolin On Cationic Exchange Capacity Swelling Degree and Morphology of Chitosan/Kaolin Composites

    Directory of Open Access Journals (Sweden)

    Ozi Adi Saputra

    2016-06-01

    Full Text Available Preparation of sulfonated-kaolin (sKao has been conducted and used as filler on chitosan matrix via solution casting method, namely chitosan/sKao (Cs/sKao. Swelling degree, cationic exchange capacity and thermal stability were evaluated to determine chitosan/sKao membranes performance as proton exchange membrane in fuel cell. Functional group analysis of chitosan, sKao and synthesized products were studied using Fourier Transform Infra-Red (FTIR spectroscopy. In this study, swelling degree and swelling area of Cs/sKao are also studied to determine of membrane ability to swelling which compare to unmodified chitosan/kaolin (Cs/Kao. The presence of sKao in chitosan matrix was able to improve cationic exchange capacity (CEC which proved by morphological study of membrane surface after CEC test. Moreover, Thermal stability of Cs/sKao showed the membrane has meet requirement for PEM application.

  19. Synthesis and characterization of kaolin with polystyrene via in-situ polymerization and their application on polypropylene

    International Nuclear Information System (INIS)

    Zhao, Songfang; Qiu, Shangchang; Zheng, Yuying; Cheng, Lei; Guo, Yong

    2011-01-01

    To improve both the mechanical and thermal properties of kaolin/polypropylene (PP) composites, kaolin was modified by using 3-(trimethoxysilyl) propylmethacrylate (YDH-570) as a coupling agent to form polymerizable particle. Styrene was radically polymerized through the immobilized vinyl using benzoyl peroxide (BPO) as an initiator. Fourier transform-infrared (FTIR) spectroscopy, particle size distribution, X-ray diffraction (XRD) and thermo-gravimetric analysis (TGA) well demonstrated that the kaolin-polystyrene particles were successfully synthesized via in-situ polymerization. While the modified kaolin and raw kaolin were introduced into the PP matrix, it could be concluded that modified kaolin/PP composites have better mechanical and thermal properties than raw kaolin/PP composites, and these improvements were attributed to the desirable dispersion of kaolin in PP matrix.

  20. Utilisation of Sand from Kaolin Washing for the Manufacture of Alkali-activated Artificial Sandstone

    Science.gov (United States)

    Vavro, Martin; Vavro, Leona; Mec, Pavel; Soucek, Kamil; Pticen, Frantisek; Reiterman, Pavel

    2017-04-01

    sand from kaolin-washing process is of several hundred thousand tonnes and it thus represent so far a relatively rarely used natural building material which is currently usually deposited in worked-out areas of kaolin quarries. One of the main reasons of very difficult usability of this sands in building material industry is their behavior when exposed to the weather. In only a very short time of exposure in outdoor condition they may change in colour from greyish white to yellow-brown or golden yellow. This colour change is accompanied by significant decrease of pH values of sand leachate up to pH ranging between 3.5 and 5.5, in extreme cases even up to 2.0. Despite these extreme chemical properties of sands under study, the artificial sandstone, very similar in the physical and mechanical properties to natural ones, was successfully prepared in the laboratory. Due to the mineralogical composition of applied sands (i.e. the presence not only of quartz, but also of feldspar and muscovite), the artificial sandstone is characterized by relatively true natural appearance.

  1. Preparation of Modified Kaolin Filler with Cesium and Its Application in Security Paper

    Directory of Open Access Journals (Sweden)

    Houssni El-Saied

    2013-01-01

    Full Text Available In this study, cesium was added intentionally during paper manufacture for protecting the papers against forgery and counterfeiting by sorbing cesium ions (Cs+ on kaolin, used as special filler in papermaking. The sorption of cesium from aqueous solution by kaolin was studied as a function of pH, shaking time, cesium initial concentration, and mass of kaolin using batch technique. The results showed that a solution containing 10 mg/L Cs+ and 250 mg of kaolin at pH 6 can be used to modify the kaolin. Paper handsheets were prepared containing various percentages of the modified kaolin. The mechanical and optical properties of paper handsheets were studied. The prepared paper handsheets were irradiated by gamma irradiation using different doses. Fourier transform infrared (FTIR spectroscopy was used to study the effect of kaolin modification by cesium and gamma irradiation on paper handsheets properties. The results indicated that modified kaolin enhanced the mechanical and optical properties of paper handsheets. Electron spin resonance (ESR spectroscopy and laser-induced breakdown spectroscopy (LIBS were also used. They provided rapid, sensitive and nondestructive techniques in differentiating between different questioned documents. This study presents a new concept in manufacturing security papers and anticounterfeiting applications.

  2. Side effects of kaolin particle films on apple orchard bug, beetle and spider communities

    NARCIS (Netherlands)

    Marko, V.; Bogya, S.; Kondorosy, E.; Blommers, L.H.M.

    2010-01-01

    The effects of multiple applications of hydrophobic kaolin particle film on apple orchard bug (Heteroptera), beetle (Coleoptera) and spider (Araneae) assemblages were studied in the Netherlands. Insecticide-free orchard plots served as a control. The kaolin applications significantly reduced the

  3. Processed kaolin affects the probing and settling behavior of Diaphorina citri (Hemiptera: Lividae).

    Science.gov (United States)

    Miranda, Marcelo P; Zanardi, Odimar Z; Tomaseto, Arthur F; Volpe, Haroldo Xl; Garcia, Rafael B; Prado, Ernesto

    2018-03-05

    Alternative methods that have the potential to reduce the entry of Diaphorina citri Kuwayama (Hemiptera: Liviidae), the major citrus pest worldwide, into commercial groves could be a viable approach for huanglongbing management. Kaolin is an aluminum silicate that when sprayed on plants forms a white particle film that interferes with host recognition by the insects. Diaphorina citri orients towards the host plants by visual and olfactory cues. The purpose of the study was to determine the effect of processed kaolin on D. citri settling (no-choice) and probing behavior [electrical penetration graph (EPG) technique] under laboratory conditions, and to study its host plant finding ability and dispersal under field conditions in the absence and presence of young shoots. Under laboratory conditions, kaolin caused an overall reduction of 40% in the number of psyllids settled on treated seedlings; furthermore, the proportion of individuals that were able to reach the phloem was 50% lower on kaolin-treated plants than on untreated plants. In the field, the plant finding ability of D. citri was disrupted on kaolin-treated trees (overall reduction of 96%), regardless of the vegetative condition, and psyllid dispersal was slower in kaolin-treated plots than in the untreated control. This study clearly demonstrates that processed kaolin interferes negatively with different aspects of the host plant finding ability of D. citri. These findings suggest that processed kaolin has a high potential to reduce huanglongbing primary infection. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  4. Effect of surface modified kaolin on properties of polypropylene grafted maleic anhydride

    Science.gov (United States)

    Yang, Ni; Zhang, Zuo-Cai; Ma, Ning; Liu, Huan-Li; Zhan, Xue-Qing; Li, Bing; Gao, Wei; Tsai, Fang-Chang; Jiang, Tao; Chang, Chang-Jung; Chiang, Tai-Chin; Shi, Dean

    To achieve reinforcement of mechanical and thermal performances of polypropylene (PP) product, this work aimed at fabrication of surface modified kaolin (M-kaolin) filled polypropylene grafted maleic anhydride (PP-g-MAH) composites with varying contents of fillers and investigation of their mechanical and thermal properties. And the prepared PP-g-MAH/M-kaolin composites were characterized by means of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Fracture analysis by SEM showed M-kaolin particles were well dispersed in the PP-g-MAH matrix. Mechanical behaviors were determined by tensile strength, tensile strain at break and impact strength analysis. Impact strength of PP-g-MAH/2 wt% M-kaolin composites was improved up to 30% comparing with unfilled composites. Thermostability had been found enhanced when M-kaolin added. The results revealed PP-g-MAH/M-kaolin composites showed the optimal thermal and mechanical properties when 2 wt% of M-kaolin was added.

  5. Assembling strategy to synthesize palladium modified kaolin nanocomposites with different morphologies

    OpenAIRE

    Li, Xiaoyu; Ouyang, Jing; Zhou, Yonghua; Yang, Huaming

    2015-01-01

    Nanocomposites of aluminosilicate minerals, kaolins (kaolinite and halloysite) with natural different morphologies assembling with palladium (Pd) nanoparticles have been successfully synthesized through strong electrostatic adsorption and chemical bonding after surface modification with 3-aminopropyl triethoxysilane (APTES). Meanwhile, the influence of different morphologies supports on catalytic hydrogenation properties was explored. The surface concentration of amino groups on the kaolins w...

  6. Sample size clay kaolin of primary in pegmatites regions Junco Serido - PB and Equador - RN

    International Nuclear Information System (INIS)

    Meyer, M.F.; Sousa, J.B.M.; Sales, L.R.; Silva, P.A.S.; Lima, A.D.D.

    2016-01-01

    Kaolin is a clay formed mainly of kaolinite resulting from feldspar weathering or hydrothermal. This study aims to investigate the way of occurrence, kaolin particle size of the pegmatites of the Borborema Province Pegmatitic in the regions of Junco do Serido-PB and Ecuador-RN. These variables were analyzed considering granulometric intervals obtained from wet sieving of samples of pegmatite mines in the region. Kaolin was received using sieves of 200, 325, 400 and 500 mesh and the sieve fractions retained by generating statistical parameters histograms. kaolin particles are extremely fine and pass in its entirety through 500 mesh sieve. The characterization of minerals in fine fractions by diffraction of X-rays showed that the relative amount of sericite in fractions retained in sieves 400 and 500 mesh impairing the whiteness and mineralogical texture kaolin production. (author)

  7. Effects of biochar on hydraulic conductivity of compacted kaolin clay.

    Science.gov (United States)

    Wong, James Tsz Fung; Chen, Zhongkui; Wong, Annie Yan Yan; Ng, Charles Wang Wai; Wong, Ming Hung

    2018-03-01

    Compacted clay is widely used as capillary barriers in landfill final cover system. Recently, biochar amended clay (BAC) has been proposed as a sustainable alternative cover material. However, the effects of biochar on saturated hydraulic conductivity (k sat ) of clay with high degree of compaction is not yet understood. The present study aims to investigate the effects of biochar on k sat of compacted kaolin clay. Soil specimens were prepared by amending kaolin clay with biochar derived from peanut-shell at 0, 5 and 20% (w/w). The k sat of soil specimens was measured using a flexible water permeameter. The effects of biochar on the microstructure of the compacted clay was also investigated using MIP. Adding 5% and 20% of biochar increased the k sat of compacted kaolin clay from 1.2 × 10 -9 to 2.1 × 10 -9 and 1.3 × 10 -8 ms -1 , respectively. The increase in k sat of clay was due to the shift in pore size distribution of compacted biochar-amended clay (BAC). MIP results revealed that adding 20% of biochar shifted the dominant pore diameter of clay from 0.01-0.1 μm (meso- and macropores) to 0.1-4 μm (macropores). Results reported in this communication revealed that biochar application increased the k sat of compacted clay, and the increment was positively correlated to the biochar percentage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. X-ray diffraction and thermal analysis of kaolins particle size fractions

    Directory of Open Access Journals (Sweden)

    Patricia dos Santos

    2013-09-01

    Full Text Available Kaolins are common geological materials and have high concentrations of kaolinite as well as the clay fraction of tropical and subtropical soils of Brazil. The characterization of kaolin is a proxy of assessing the contribution of kaolinite to important soil chemical and mineralogical attributes. This study evaluated four kaolins (commercial kaolin A (CCA, commercial kaolin B (CCB, pink sandy kaolin A (CRA and green sandy kaolin A (CVA in the original form and after particle size separation into: sand (200-53 mm, coarse silt (53-20 m, fine silt (20-2 m, large clay (2-1m, medium clay (1-0.5 m and fine clay (<0.5m fractions. The minerals were identified by X-ray diffraction (XRD and evaluated for crystallinity (kaolinite and halloysite through indexes Hughes and Brown, Amigó, Bramão and the dehydroxylation temperature. The physical fractionation was efficient to concentrate minerals in specific size fractions which were not identified in the original material. In CCA kaolin was concentrated one mineral which remains unidentified in fine fractions, in kaolin CRA, zircon was concentrated in the coarse silt and different silicates in the fine fractions, in kaolin CCB were concentrated kaolinite and a silicate in the medium and coarse clay fractions. The estimate by X-ray diffraction overestimated the amount of kaolinite and halloysite underestimated when compared to quantification by thermal gravimetric analysis The crystallinity index exhibit different behaviors depending on the mineralogy of each material, thus the correlation between the crystallinity of kaolinite and / or halloysite and other variables, may be compromised, especially in materials with distinct geological origins.

  9. Mussel inspired preparation of amine-functionalized Kaolin for effective removal of heavy metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Qiang; Liu, Meiying; Deng, Fengjie [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang, 330031 (China); Wang, Ke [Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing, 100084 (China); Huang, Hongye; Xu, Dazhuang; Zeng, Guangjian [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang, 330031 (China); Zhang, Xiaoyong, E-mail: xiaoyongzhang1980@gmail.com [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang, 330031 (China); Wei, Yen [Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing, 100084 (China)

    2016-09-15

    Adsorption has been well regarded as a promising and efficient method for the removal of low concentration heavy metal ions in aqueous solutions. And kaolin has been considered as a kind of low cost and environment-friendly adsorbent for its abundant in nature. But the low adsorption capacity to heavy metal ions and severe aggregation in solution restrains its application. In this work, an environment-friendly adsorbent (denoted as Kaolin-PDA-PEI) was prepared based on mussel inspired chemistry and Michael addition reaction between high reaction activity of polydopamine (PDA) and polyethyleneimine (PEI), which was possesses a number of amine groups. The amine groups have displayed strong adsorption affinity towards copper ions. The successful modification of Kaolin by PDA and PEI was confirmed by a series of analyses, such as Fourier transform infrared spectroscopy, transmission electron microscopy, thermal gravimetry analysis and X-ray photoelectron spectroscopy. The effects of various parameters such as contact time, pH, initial concentrations of copper ions and temperature on copper ion adsorption by Kaolin-PDA-PEI were investigated. Kaolin-PDA-PEI shows higher adsorption capacity as compared with the raw Kaolin. The kinetic adsorption data were analyzed using pseudo-first-order, pseudo-second-order and intraparticle diffusion model. The Langmuir isotherm and Freundlich isotherm equilibrium model were applied to adsorption isotherm data to find the better fit isotherm. The results showed that adsorption process was well fitted by Langmuir isotherm model. The values of thermodynamics constants such as entropy change (ΔS{sup 0}), enthalpy change (ΔH{sup 0}) and Gibbs free energy (ΔG{sup 0}) were also calculated. The results indicated that the adsorption process of Kaolin-PDA-PEI were endothermic and spontaneous. - Graphical abstract: Amino groups functionalized Kaolin was facilely prepared via mussel inspired chemistry. The modified Kaolin exhibited much

  10. Mussel inspired preparation of amine-functionalized Kaolin for effective removal of heavy metal ions

    International Nuclear Information System (INIS)

    Huang, Qiang; Liu, Meiying; Deng, Fengjie; Wang, Ke; Huang, Hongye; Xu, Dazhuang; Zeng, Guangjian; Zhang, Xiaoyong; Wei, Yen

    2016-01-01

    Adsorption has been well regarded as a promising and efficient method for the removal of low concentration heavy metal ions in aqueous solutions. And kaolin has been considered as a kind of low cost and environment-friendly adsorbent for its abundant in nature. But the low adsorption capacity to heavy metal ions and severe aggregation in solution restrains its application. In this work, an environment-friendly adsorbent (denoted as Kaolin-PDA-PEI) was prepared based on mussel inspired chemistry and Michael addition reaction between high reaction activity of polydopamine (PDA) and polyethyleneimine (PEI), which was possesses a number of amine groups. The amine groups have displayed strong adsorption affinity towards copper ions. The successful modification of Kaolin by PDA and PEI was confirmed by a series of analyses, such as Fourier transform infrared spectroscopy, transmission electron microscopy, thermal gravimetry analysis and X-ray photoelectron spectroscopy. The effects of various parameters such as contact time, pH, initial concentrations of copper ions and temperature on copper ion adsorption by Kaolin-PDA-PEI were investigated. Kaolin-PDA-PEI shows higher adsorption capacity as compared with the raw Kaolin. The kinetic adsorption data were analyzed using pseudo-first-order, pseudo-second-order and intraparticle diffusion model. The Langmuir isotherm and Freundlich isotherm equilibrium model were applied to adsorption isotherm data to find the better fit isotherm. The results showed that adsorption process was well fitted by Langmuir isotherm model. The values of thermodynamics constants such as entropy change (ΔS"0), enthalpy change (ΔH"0) and Gibbs free energy (ΔG"0) were also calculated. The results indicated that the adsorption process of Kaolin-PDA-PEI were endothermic and spontaneous. - Graphical abstract: Amino groups functionalized Kaolin was facilely prepared via mussel inspired chemistry. The modified Kaolin exhibited much enhanced adsorption

  11. Synthesis of Zeolite A from Kaolin (Shwe Taung Clay)

    International Nuclear Information System (INIS)

    Mie Mie Han Htun; Mu Mu Htay

    2010-12-01

    The synthesis of Zeolite A from locally available kaolin clay (Shwe Taung) in Myanmar has been attempted. The kaolinite was converted to metakaoli, by treating with NaOH at 820C for 1hr, and hydrothermal treatment.It was found that the solution of fused clay powder can be crystallized at 100C under ambient pressure to synthesize Zeolite A. The process variables for synthesis have been optimized in order to produce Zeolite A at a lower price. The mole ratio of SiO2/Al2O3 for kaolin was fixed at 2.54. The effects of various factors (aging time and agitation time) on the structure of the sample were extensively investigated. The Shwe Taung clay was characterized by X-ray Diffraction (XRD), X-ray fluorescence (XRF) and Scanning Electron Microscopy (SEM). The samples were characterized by XRD. The results show that the pure form Zeolite A can be prepared with a molar composition of (2.54 SiO3: Al2O3: 5.8Na2O: 256 H2O) by agitation at room temperature for 30min. The mixture was aged for 24 hour at the same temperature and crystallized at 100C for 48 hour.

  12. Synthesis of type A zeolite from calcinated kaolin

    International Nuclear Information System (INIS)

    Rodrigues, E.C.; Neves, R.F.; Souza, J.A.S.; Moraes, C.G.; Macedo, E.N.

    2011-01-01

    The mineral production has caused great concern in environmental and industrial scenario due to the effects caused to the environment. The industries of processing kaolin for paper are important economically for the state of Para, but produce huge quantities of tailings, which depend on large areas to be stocked. This material is rich in silico-aluminates can be recycled and used as raw material for other industries. The objective is to synthesize zeolite A at different temperatures of calcination and synthesis. The starting materials and synthesis of zeolite A have been identified and characterized through analysis of X-ray diffraction (DRX) and scanning electron microscopy (MEV). The synthesis process of zeolite A, using as source of silica and the aluminum metakaolin, which was calcined at temperatures of 700 ° C and 800 ° C for 2 hours of landing in a burning furnace type muffle. Observed in relation to the calcination of kaolin as the main phase, the metakaolin. This is just a removal of water from its structure, so we opted for the lower temperature, less energy consumption. The synthesis process of zeolite A, produced good results for the formation of zeolites type A, which were characterized with high purities. (author)

  13. ADSORPTION OF GIBBERELLIC ACID ONTO NATURAL KAOLIN FROM TATAKAN, SOUTH KALIMANTAN

    Directory of Open Access Journals (Sweden)

    Sunardi Sunardi

    2010-06-01

    Full Text Available Adsorption of gibberellic acid (GA3 onto raw and purified kaolin from Tatakan, South Kalimantan was investigated in this study. Purification process was done by sedimentation to obtain relative pure kaolinite. Raw and purified kaolin samples were characterized by Fourier transformed infrared (FTIR spectroscopy and X-ray diffractometer (XRD. The adsorption process was carried out in a batch system and the effect of pH, contact time and GA3 concentration were experimentally studied to evaluate the adsorption capacity. The amount of GA3 adsorbed was determined by UV spectrophotometer. The result showed that the raw kaolin from South Kalimantan consist of 53.36% kaolinite, 29.47% halloysite, 4.47% chlorite, 11.32% quartz and 1.38% christobalite and the purified kaolin consist of 73.03% kaolinite, 22.6% halloysite, 0.77% chlorite, 1.37% quartz and 2.23% christobalite Adsorption experimental indicate that the optimum adsorption took place at pH 7 and contact time for 4 h. Adsorption of GA3 was described by the Langmuir adsorption isotherm model with adsorption capacity of 8.91 mg/g on raw kaolin and 10.38 mg/g on purified kaolin.   Keywords: kaolin, gibberellic acid, adsorption

  14. Monitoring of Radiation Levels in Mines of Kaolin Located in the Region Serido-PB, Brazil

    International Nuclear Information System (INIS)

    Guerra Spacov, Isabel Cristina; Dos Santos Amaral, Milton; Araujo dos Santos Junior, Jose

    2015-01-01

    Kaolin is formed mainly by kaolinite and is used in many industrial sectors. Kaolin may be associated with by-products such as quartz, mica, feldspar and sand. The background radiation from nature is very important, since it represents the main source of human exposure to radiation. In kaolin, radionuclides are present as the 40 K and series 238 U and 232 Th. This study aimed to obtain the rates of effective doses of kaolin mines in the region of Serido-PB, Brazil, where there are several productions and mineral occurrences, including kaolin and uranium at nearby areas. Four kaolin mines located in the Serido-PB region were monitored by a portable discriminator detector NaI(Ti). Measurements were obtained outdoors in triplicate, at a distance of 1.0 meters from the Earth's surface. According to the report of UNSCEAR, the world average effective dose from exposure to natural radiation sources is 2.42 mSvy -1 . the rates of effective doses identified in this study ranged from 1.37 mSvy -1 , and provided the construction of isodose curves. The highest dose rate obtained may be related to pegmatite bodies in a nearby area that contain uranium minerals. However, based on the development of this research, the results indicate that further study in this area is needed in order to infer damage associated with mining of kaolin in the Serido-PB area. (Author)

  15. Kaolin modulates ABA and IAA dynamics and physiology of grapevine under Mediterranean summer stress.

    Science.gov (United States)

    Dinis, L-T; Bernardo, S; Luzio, A; Pinto, G; Meijón, M; Pintó-Marijuan, M; Cotado, A; Correia, C; Moutinho-Pereira, J

    2018-01-01

    The foliar exogenous application of kaolin, a radiation-reflecting inert mineral, has proven to be an effective short-term climate change mitigation strategy for Mediterranean vineyards. In this work, we address the hypothesis that kaolin could improve both the hormonal dynamics and physiological responses of grapevines growing in Douro Region, northern Portugal. For this purpose, the leaf water potential, gas exchange and chlorophyll a fluorescence parameters were monitored, as well as the abscisic acid (ABA) and indole-3-acetic acid (IAA) quantification and immunolocalization were assessed. The study revealed a slight decrease in ABA and an increase in IAA in the kaolin treatment, which in turn were associated with the improvement of physiological performance. A month after spraying, kaolin improves the water potential respectively, 30% and 17% in the predawn and midday periods. Besides, plants treated with kaolin showed higher values of stomatal conductance, net CO 2 assimilation rate and intrinsic water use efficiency. Kaolin also ameliorates the effective PSII efficiency (67%), as well as the maximum quantum efficiency of photosystem II and the photosynthetic electron transport rate (>73%). These results were consistent with the higher photochemical quenching and the lower non-photochemical quenching observed in treated leaves and with the better performance obtained by the JIP test parameters. Physiological and hormonal analysis confirmed that kaolin effectively enhance grapevine summer stress tolerance. Copyright © 2017 Elsevier GmbH. All rights reserved.

  16. Potassium Capture by Kaolin, Part 2: K2CO3, KCI, and K2SO4

    DEFF Research Database (Denmark)

    Wang, Guoliang; Jensen, Peter Arendt; Wu, Hao

    2018-01-01

    residence time on the reaction was investigated. The results showed that the K-capture level (C-K) (g potassium reacted by per g kaolin available) of K2CO3 and KCI by kaolin generally followed the equilibrium predictions at temperatures above 1100 degrees C, when using a kaolin particle size of D50 = 5.......47 mu m and a residence time of 1.2 s. This revealed that a nearly full conversion was obtained without kinetic or transport limitations at the conditions applied. At 800 and 900 degrees C, the measured conversions were lower than the equilibrium predictions, indicating that the reactions were either...

  17. Sedimentation Characteristics of Kaolin and Bentonite in Concentrated Solutions

    Directory of Open Access Journals (Sweden)

    Abdulah Obut

    2005-11-01

    Full Text Available The sedimentation characteristics of two clays, namely kaolinite and bentonite, were determinated at high clay (5 % wt/vol and electrolyte (1 N concentrations using various inorganic-organic compounds. It was observed that the settling behaviour of kaolinite (1:1 clay and montmorillonite (2:1 clay is quite different due to the structural differences between these minerals. Although, similar initial settling rates and final sediment volumes were obtained after 24 hours of settling time for kaolin suspensions, the corresponding rates and volumes for bentonite suspensions varied greatly with the used chemical compound. According to the experimental results, a further intensive theoretical and experimental investigation is needed to reveal the mechanism underlying the sedimentation characteristics of clay minerals at high clay and electrolyte concentrations.

  18. Physico-Chemical Properties of Kaolin-Organic Acid

    Directory of Open Access Journals (Sweden)

    Yeo S.W.

    2017-01-01

    Full Text Available Soil with more than 20% of organic content is classified as organic soil in Malaysia. Contents of organic soil consist of different types of organic and inorganic matter. Each type of organic matter has its own characteristic and its effect on the properties of the soil is different. Hence, a good understanding on the effect of specific organic and inorganic matter on the physico-chemical characteristic of organic soils can serve as a guide for predicting the properties of organic soils. The main objective is to unveil the effect of organic acid on the physico-chemical properties of soil. Artificial organic soil (kaolin mixed with organic acid was utilized in order to minimize the geochemical variability of studied soil. The organic acid which consists of humic acid and fulvic acid was extracted from highly humificated plant–based compost. The effect of organic acid on the physico-chemical properties of soil was determined by varying the concentration of organic acid. The specific gravity, Atterberg limits, pH, bulk chemical composition and the functional group of kaolin-organic acid were determined. It was found that the plasticity index, specific gravity and pH value were decreased with lowered concentration of organic acid. However, the liquid limits and plastic limits were found to be increased with the concentration decrement of organic acid. The analysis of XRF on the bulk chemical composition and analysis of FTIR spectra on the functional group of artificial organic soils with different concentration have confirmed little geochemical variability between samples.

  19. Synthesis and characterization of mesoporous NaY zeolite from natural Blitar’s kaolin

    Science.gov (United States)

    Khalifah, S. N.; aini, Z. N.; Hayati, E. K.; Aini, N.; Prasetyo, A.

    2018-03-01

    Mesoporous NaY Zeolite has been synthesized from calcined natural Blitar’s kaolin with the addition of NaOH and CTABr surfactant as mesoporous template by hydrothermal method. Natural kaolin was calcinated with different time and temperature to change kaolin to metakaolin. X-ray diffraction data showed that mesoporous NaY zeolite was formed with impurities compound of sodalite, kaolin and quartz phases. The BET analysis resulted that the pore of NaY Zeolite belongs to mesoporous type with pore size 9,421 nm. Characterization from FTIR confirmed about the functional group of zeolites (988, 776, 663, 464 cm-1). Scanning electron microscopy characterization showed that the morphological of mesoporous NaY zeolites have uniform and crystalline particles formed.

  20. Technological properties of kaolin from Para; Propriedades tecnologicas do caulin do Para

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrando, E.; Martin-Cortes, G.R.; Esper, F.J.; Wiebeck, H.; Alves Junior, P.; Valenzuela-Diaz, F.R., E-mail: germac@usp.br [Universidade de Sao Paulo (PMT/EP/USP), Sao Paulo, SP (Brazil). Escola Politecnica. Departamento de Engenharia Metalurgica e de Materiais

    2011-07-01

    The NE of the State of Para, is notable for its large reserves of kaolin for paper. Kaolin is a mineral composed of hydrated aluminum silicates such as kaolinite and halloysite. The exploitation of these reserves to generate products with higher commercial value, especially in the industries of adsorbents and catalysts, is what motivates the continuous study of technological properties of the Amazon kaolin's. Thus, this paper presents a technological characterization of a sample of kaolin from Para State by X-ray diffraction, SEM - scanning electron microscopy and infrared spectroscopy. The results of preliminary tests indicate that the sample consists for the most part by kaolinite present in low concentrations of quartz and anatase. (author)

  1. Parasitoids of boll weevil Anthonomus grandis and resident predators in kaolin-treated cotton

    Directory of Open Access Journals (Sweden)

    Roberta Leme Santos

    2013-12-01

    Full Text Available Simultaneous use of control methods is essential to reach success in managing arthropod pests. The current study investigated the effect of kaolin application on resident predators in the cotton plant canopy and parasitism of boll weevil on abscised squares in the field, and parasitism of boll weevil in the laboratory. Predators Araneae, Formicidae, Chrysopidae, and Coccinellidae showed similar seasonal densities for kaolin-treated and untreated cotton fields as well as the emergence rate of the parasitoids Bracon vulgaris Ashmead (Hymenoptera: Braconidae and Catolaccus grandis Burks (Hymenoptera: Pteromalidae from abscised field-collected structures. Under laboratory conditions, the parasitism of boll weevil larvae infesting squares was similar when treated and untreated squares with kaolin were offered to the parasitoid under free choice test. Therefore, the results show that spraying cotton fields with kaolin does not affect the natural biological control by parasitoids of boll weevil and pink bollworm and resident predators naturally occurring in cotton fields.

  2. Kaolin particle films suppress many apple pests, disrupt natural enemies and promote woolly apple aphid

    NARCIS (Netherlands)

    Markó, V.; Blommers, L.H.M.; Bogya, S.; Helsen, H.H.M.

    2008-01-01

    Multiple applications of hydrophobic kaolin particle film in apple orchards suppressed numbers of blossom weevil (Anthonomus pomorum), brown leaf weevil (Phyllobius oblongus), attelabid weevil (Caenorhinus pauxillus), leafhoppers (Empoasca vitis and Zygina flammigera) and green apple aphid (Aphis

  3. 40 CFR 180.1180 - Kaolin; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... Kaolin, when used on crops (apples, apricots, bananas, beans, cane berries, citrus fruits, corn, cotton... permit the marketing of the food commodities in this paragraph when treated in accordance with the...

  4. Facile Selective and Diverse Fabrication of Superhydrophobic, Superoleophobic-Superhydrophilic and Superamphiphobic Materials from Kaolin.

    Science.gov (United States)

    Qu, Mengnan; Ma, Xuerui; He, Jinmei; Feng, Juan; Liu, Shanshan; Yao, Yali; Hou, Lingang; Liu, Xiangrong

    2017-01-11

    As the starting material, kaolin is selectively and diversely fabricated to the superhydrophobic, superoleophobic-superhydrophilic, and superamphiphobic materials, respectively. The wettability of the kaolin surface can be selectively controlled and regulated to different superwetting states by choosing the corresponding modification reagent. The procedure is facile to operate, and no special technique or equipment is required. In addition, the procedure is cost-effective and time-saving and the obtained super-repellent properties are very stable. The X-ray photoelectron spectroscopy analysis demonstrates different changes of kaolin particles surfaces which are responsible for the different super-repellency. The scanning electron microscopy displays geometric micro- and nanometer structures of the obtained three kinds of super-repellent materials. The results show that kaolin has good applications in many kinds of superwetting materials. The method demonstrated in this paper provides a new strategy for regulating and controlling the wettability of solid surfaces selectively, diversely, and comprehensively.

  5. PHYSICAL PROPERTIES OF KAOLIN/SAND SLURRY USED DURING SUBMERSIBLE MIXER PUMP TESTS AT TNX

    International Nuclear Information System (INIS)

    HANSEN, ERICH

    2005-01-01

    The purpose of this task is to characterize the physical properties of the kaolin/sand slurries used during the testing of a new submersible mixer pump (SMP) which had undergone performance testing at the TNX Waste Tank mockup facility from July 2004 through May 2005. During this time period, four identical SMPs were subjected to various water tests and four different tests using different batches of kaolin/sand slurries. The physical properties of the kaolin/sand slurries were measured for three of the four tests. In these tests, three different sample locations were used to pull samples, the SMP cooling water exit (CWE), the SMP fluid flow field (FFF), and SMP effective cleaning radius (ECR). The physical properties measured, though not for each sample, included rheology, weight percent total solids (wt% TS), density, kaolin/sand slurry particle size distribution (PSD), weight percent and particles size distribution of material greater than 45 microns

  6. Evaluation of The Use of Bentonite, Kaolin and Feldspar For Immobilizing The Uranium Radionuclide Slugdewaste

    International Nuclear Information System (INIS)

    Prayitno

    2006-01-01

    The experimental investigation on the mixture of bentonite, kaolin, feldspar, sludge waste and with the ratio of bentonite, kaolin, feldspar for evaluating its effectiveness has been done. Experimentally, this investigation is the preliminary study of the use of bentonite, kaolin, feldspar as a material for the immobilization of sludge waste containing material element especially uranium. This investigation was conducted by mixing waste (2,5; 5; 7.5; 10; 12.5 and 15 %) of total weight sludge waste and bentonite, kaolin, feldspar with of 800, 900 and 1000 o C temperature. The obtained the process condition in which the uranium fraction immobilized could be kept in the limit of safety standard for the sludge waste. Therefore, it could be concluded that the addition of hay ash as an additive in the formation of block monolith tend to minimize the leached sludge waste in the leaching media. (author)

  7. A Study on Kaolin and Titanium dioxide affecting Physical Properties of Electrocoating

    International Nuclear Information System (INIS)

    Yang, Wonseog; Hwang, Woonsuk

    2013-01-01

    The electrocoating for automotive bodies is pigmented with a mixture of titanium dioxide and kaolin. In this study, the effects of titanium dioxide and kaolin contents in coating on electrodeposition process, drying, and surface properties such as surface roughness, gloss, impact resistance and corrosion resistance were investigated. Titanium dioxide and kaolin in coating do not have a decisive effect on curing reaction during drying and corrosion resistance but on gloss, surface roughness, impact resistance and electrodeposition process of coating. According to its size and shape on coating surface, pigment contents increased during drying process. However, the contents of kaolin and TiO 2 in coating didn't affect the corrosion resistance on zinc phosphated substrate, and the curing properties

  8. Flotation of kaolinite from tailings of kaolin-washing plants by cationic collectors

    OpenAIRE

    Barani Kianoush

    2016-01-01

    Traditional processing of kaolin is achieved by dispersion of the mined ore and classification by means of multistage hydrocyclones. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back to the quarry. In this research recovery of kaolinite from tailings of the Zonoupz kaolin washing plant, which is located in Iran, was investigated by cationic flotation. Flotation experiments showed that flotation of kaolinite from tailings was much better in an ac...

  9. Recovery of kaolinite from tailings of Zonouz kaolin-washing plant by flotation-flocculation method

    OpenAIRE

    Kianoush Barani; Masoud Kalantari

    2018-01-01

    The traditional processing of kaolin is achieved by dispersion of the mined ore and classification by multistage hydrocyclone plants. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back into the quarry. In this research, recovery of kaolinite from tailings of Zonouz kaolin washing plant, which is located in Iran was investigated by flotation and flotation- flocculation. Flotation experiments show that the flotation of kaolinite from the tailings i...

  10. Influence of kaolin addition on the dynamics of oxygen mass transport in polyvinyl alcohol dispersion coatings

    OpenAIRE

    Nyflött, Åsa; Axrup, Lars; Gunilla, Carlsson; Järnström, Lars; Lestelius, Magnus; Moons, Ellen; Wahlström, Torbjörn

    2015-01-01

    The permeability of dispersion barriers produced from polyvinyl alcohol (PVOH) and kaolin clay blends coated onto polymeric supports has been studied by employing two different measurement methods: the oxygen transmission rate (OTR) and the ambient oxygen ingress rate (AOIR). Coatings with different thicknesses and kaolin contents were studied. Structural information of the dispersion-barrier coatings was obtained by Fourier transform infrared spectroscopy (FTIR) spectroscopy and scanning ele...

  11. Facile Fabrication of a Hierarchical Superhydrophobic Coating with Aluminate Coupling Agent Modified Kaolin

    OpenAIRE

    Hui Li; Mengnan Qu; Zhe Sun; Jinmei He; Anning Zhou

    2013-01-01

    A superhydrophobic coating was fabricated from the dispersion of unmodified kaolin particles and aluminate coupling agent in anhydrous ethanol. Through surface modification, water contact angle of the coating prepared by modified kaolin particles increased dramatically from 0° to 152°, and the sliding angle decreased from 90° to 3°. Scanning electron microscopy was used to examine the surface morphology. A structure composed of micro-nano hierarchical component, combined with the surface modi...

  12. Mineralogical characteristics of Cretaceous-Tertiary kaolins of the Douala Sub-Basin, Cameroon

    Science.gov (United States)

    Bukalo, Nenita N.; Ekosse, Georges-Ivo E.; Odiyo, John O.; Ogola, Jason S.

    2018-05-01

    As a step in evaluating the quality of Cretaceous-Tertiary kaolins of the Douala Sub-Basin, their mineralogical characteristics were determined. The X-ray diffractometry technique was used to identify and quantify the mineral phases present in bulk and smectite > illite, with mean values of 33.01 > 11.20 > 4.41 wt %; and 72.23 > 10.69 > 4.69 wt %, in bulk and <2 μm fractions, respectively. The kaolins, micromorphologically, consisted of pseudo-hexagonal and thin platy particles; swirl-textured particles; and books or stacks of kaolinite particles. Three main reactions occurred during heating of the kaolins: a low temperature endothermic reaction, observed between 48 and 109 °C; a second low temperature peak, observed between 223 and 285 °C; and a third endothermic peak was found between 469 and 531 °C. In addition, an exothermic reaction also occurred between 943 and 988 °C in some of the samples. The absence of primary minerals such as feldspars and micas in most of these kaolins is an indication of intensive weathering, probably due to the humid tropical climate of the region. The different morphologies suggested that these kaolins might have been transported. Therefore, a humid tropical climate was responsible for the formation of Cretaceous-Tertiary kaolins of the Douala Sub-Basin through intense weathering of surrounding volcanic and metamorphic rocks.

  13. Mineralogical variation in the size fractions of a Ranong kaolin, southern Thailand

    Science.gov (United States)

    Pisutha-Arnond, Visut; Phuvichit, Suraphol; Leepowpanth, Quanchai

    A representative crude Ranong kaolin from the Thungkla-Ranong mine was separated into > 2 mm (granule), 2-1 mm (very coarse sand), 1-0.5 mm (coarse sand), 0.5-0.25 mm (medium sand), 0.25-0.125 mm (fine sand), 0.125-0.062 mm (very fine sand) and 62-28, 28-14, 17-7, 7-4, 4-2, 2-1 and dispersive X-ray spectrometer (EDX). Kaolin group minerals were differentiated by using XRD in combination with various chemical and heat treatments together with TEM, SEM and DTA. The Ranong kaolin consists predominantly of tubular halloysite, poorly crystallized kaolinite and quartz with minor amounts of mica and K-feldspars. Other trace constituents include gibbsite, tourmaline, zircon and colored impurities (i.e. extractable iron hydroxide coating on clay mineral surface). The kaolin minerals are found in all size fractions by which their contents and halloysite/kaolinite ratios increase as the particle sizes become finer. Quartz and mica are also detected in almost all size fractions. They are, however, more abundant with coarsening particle size. Gibbsite, K-feldspar and tourmaline are mainly concentrated in the fine sand to silt size fractions. Crystallinity of kaolin minerals as measured by XRD varied moderately with size. Relatively pure kaolin minerals, predominantly halloysite and kaolinite, can be obtained in the particle size below 1 or 2 μm.

  14. Effect of the rate of calcination of kaolin on the properties of metakaolin-based geopolymers

    Directory of Open Access Journals (Sweden)

    B.B. Kenne Diffo

    2015-03-01

    Full Text Available Kaolin samples of the same mass were treated at 700 °C for the same duration of 30 min by varying the rate of calcination (1, 2.5, 5, 10, 15 and 20 °C/min in order to obtain metakaolins which were used to produce geopolymers. Depending on the nature of each type of material, kaolin, metakaolins and geopolymers were characterized using thermal analysis, chemical analysis, XRD, FTIR, particle size distribution, specific surface area, bulk density, setting time and compressive strength. FTIR and XRD analyses showed that metakaolins except at 1 °C/min contained residual kaolinite whose quantity increased with the rate of calcination of kaolin and which influenced the characteristics of geopolymers. Thus as the rate of calcination of kaolin increased, the setting time increased (226 min (rate of 1 °C/min–773 min (rate of 20 °C/min while the compressive strength reduced (49.4 MPa (rate of 1 °C/min–20.8 MPa (rate of 20 °C/min. From the obtained results the production of geopolymers having high compressive strength along with low setting time requires that the calcination of kaolin be carried out at a low rate.

  15. Treatment of Waste Lubricating Oil by Chemical and Adsorption Process Using Butanol and Kaolin

    Science.gov (United States)

    Riyanto; Ramadhan, B.; Wiyanti, D.

    2018-04-01

    Treatment of waste lubricating oil by chemical and adsorption process using butanol and kaolin has been done. Quality of lubricating oil after treatment was analysis using Atomic Absorption Spectrophotometer (AAS) and Gas Chromatography-Mass Spectrometry (GC-MS). The effects of the treatment of butanol, KOH, and kaolin to metals contain in waste lubricating oil treatment have been evaluated. Treatment of waste lubricating oil has been done using various kaolin weight, butanol, and KOH solution. The result of this research show metal content of Ca, Mg, Pb, Fe and Cr in waste lubricating oil before treatment are 1020.49, 367.02, 16.40, 36.76 and 1,80 ppm, respectively. The metal content of Ca, Mg, Pb, Fe and Cr in the waste lubricating oil after treatment are 0.17, 9.85, 34.07, 78.22 and 1.20 ppm, respectively. The optimum condition for treatment of waste lubricating oil using butanol, KOH, and kaolin is 30 mL, 3.0 g and 1.5 g, respectively. Chemical and adsorption method using butanol and kaolin can be used for decrease of metals contain in waste lubricating oil.

  16. Effects of kaolin particle films on the life span of an orb-weaver spider.

    Science.gov (United States)

    Benhadi-Marín, Jacinto; Pereira, José Alberto; Santos, Sónia A P

    2016-02-01

    Araniella cucurbitina (Araneae: Araneidae) is a widespread orb-weaver spider commonly found in agroecosystems. Mineral particle films such as kaolin, due to their protective or anti-feeding action, can represent an alternative to pesticides, especially in organic farming systems, but little is known about its effects on A. cucurbitina. Therefore, we tested the effect of kaolin sprays on the life span of A. cucurbitina under laboratory conditions. Four treatments were tested encompassing different exposure routes. Thus, kaolin sprays were applied on (i) the surface, (ii) the prey (fly), (iii) the spider and (iv) both spider & prey. A control group was tested with water in each treatment. Results showed that sprays of kaolin significantly affected the survival of A. curcubitina when applications were done on the surface and on both spider & prey registering a reduction of 48% and 56%, respectively. Spiders in control obtained higher probability of reaching alive at the end of the assay than those treated with kaolin. Differences observed can be explained by the feeding behavior of the species and may depend on the consumption of the web by the spider and the ratio spider/fly for body size. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Kaolin in the diet and its effects on performance, litter moisture and intestinal morphology of broiler chickens

    Directory of Open Access Journals (Sweden)

    Marina Jorge de Lemos

    2015-10-01

    Full Text Available The objective of this study was to evaluate the effect of the addition of kaolin in the diet on performance, litter moisture and intestinal morphology of broiler chickens. Four hundred ninety-two broiler chickens distributed in a completely randomized design with three treatments and four replicates of 41 birds each, divided into three periods (15-21; 22-34; 35-52 days were used. The following treatments were: Control - reference diet without added kaolin; treatment 1 - reference diet + 0.75% kaolin; Treatment 2 - reference diet + 1.5% kaolin. The variables analyzed were: feed intake, average weight, average weight gain, feed conversion, litter moisture, villus height and crypt depth. The inclusion of kaolin in the diet significantly reduced feed intake, increased weight and average weight gain and improved feed conversion of broilers. The litter moisture decreased significantly after the inclusion of kaolin in the diet. The height of the duodenal villi of broilers increased significantly after inclusion of kaolin, while crypt depth was not influenced. The inclusion 0.75% of kaolin in the diet improved the performance, decreased litter moisture and benefited the intestinal integrity of broilers.

  18. Recent development of high gradient superconducting magnetic separator for kaolin in China

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Zian; Wang, Meifen; Ning, Fei Peng; Yang, Huan; Zhang, Guoqing; Hou, Zhi Long; Liu, Zhaong Xiu; Dai, Zhong [Institute of High Energy Physics and University of Chinese Academy of Sciences, Beijing (China); Li, Pei Yong; Zhang, Yiting; Wang, Zhaolian [Weifang Xinli Superconducting Technology Co.,Ltd., Weifang (China)

    2017-03-15

    A series of high gradient superconducting magnetic separator (HGMS) for kaolin has been developed. It is used for processing kaolin to increase the brightness or whiteness whether it is for paper or ceramic applications. The HGMS system mainly consists of a solenoid magnet with a zero boil-off helium cryostat, a double reciprocating canisters system, and a PLC (Process Logic Controller) fully automatic control system based on SCADA (Supervisory Control and Data Acquisition) system. We have successfully developed CGC-5.5/300 and CGC-5.0/500 HGMS systems in the recent years, and now three sets of them are on-site operation in different customers. This paper will present recent progress of the HGMS system, the results of some experiments on processing kaolin clay used HGMS, and the on-site operation.

  19. Recent development of high gradient superconducting magnetic separator for kaolin in China

    International Nuclear Information System (INIS)

    Zhu, Zian; Wang, Meifen; Ning, Fei Peng; Yang, Huan; Zhang, Guoqing; Hou, Zhi Long; Liu, Zhaong Xiu; Dai, Zhong; Li, Pei Yong; Zhang, Yiting; Wang, Zhaolian

    2017-01-01

    A series of high gradient superconducting magnetic separator (HGMS) for kaolin has been developed. It is used for processing kaolin to increase the brightness or whiteness whether it is for paper or ceramic applications. The HGMS system mainly consists of a solenoid magnet with a zero boil-off helium cryostat, a double reciprocating canisters system, and a PLC (Process Logic Controller) fully automatic control system based on SCADA (Supervisory Control and Data Acquisition) system. We have successfully developed CGC-5.5/300 and CGC-5.0/500 HGMS systems in the recent years, and now three sets of them are on-site operation in different customers. This paper will present recent progress of the HGMS system, the results of some experiments on processing kaolin clay used HGMS, and the on-site operation

  20. The mechanical and thermal characteristics of phenolic foam reinforced with kaolin powder and glass fiber fabric

    Science.gov (United States)

    Xiao, Wenya; Huang, Zhixiong; Ding, Jie

    2017-12-01

    In this work, kaolin powder and glass fiber fabric were added to PF in order to improve its thermal stability and mechanical property. Micro-structures of carbonized PF with kaolin powder were inspected by scanning electron microscopy (SEM) to demonstrate the filler’s pinning effect. SEM results illustrated modified PF had well morphology after high-temperature heat treatment. The Fourier transform infrared spectrometer (FTIR) test was carried out and found that kaolin powder only physically dispersed in PF. The compression test and thermal weight loss test were done on two groups of modified PF (Group A: add powder and fabric; Group B: add powder only). Results showed that all modified PF were better than pure PF, while foams with powder and fabric showed better mechanical characteristic and thermal stability compared with foams with powder only.

  1. Incorporation of feasibility study of residue thin kaolin in of porcelain formulations production

    International Nuclear Information System (INIS)

    Almeida, V.S. de; Ferreira, E.C.; Oliveira, T.M. de; Freitas, K.D. de Araujo; Soares Filho, J.E.; Sousa, F.J.P. de

    2016-01-01

    The porcelain is the more advanced product among traditional ceramics due to the high technology used in its manufacture and its excellent technological and aesthetic properties. Due to the continuing worldwide development, kaolin processing industries have increased their productivity and consequently generating large amounts of waste, contributing to environmental degradation. Studies are being conducted to analyze the incorporation of such wastes in the ceramic mass compositions. The objective of this study was to evaluate 4 formulations of porcelain as the possibility of using waste coming from the last stage of kaolin processing. Processing occurred by wet grinding process, with uniaxial compacting pressure of 45 MPa after heat treatment at 1250 ° C. Technological tests were carried out physical and mechanical product. The results showed that the addition of fine kaolin residue was presented as an efficient alternative for the porcelain industry. (author)

  2. Effect of kaolin treatment temperature on mortar chloride permeability

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    2007-03-01

    Full Text Available The present paper discusses the results of chloride resistance tests conducted on ordinary Portland cement (OPC mortars containing a Colombian kaolin pre-treated at temperatures of from 600 to 800 ºC. The resulting metakaolin (MK was added to OPC mortar mixes in proportions of 10 and 20% by cement weight. The mortars were compared for physical and chemical properties, including capillary absorption, chloride permeability and pore microstructure as assessed by mercury porosimetry. The best performance was recorded for the samples containing 20% of the material treated at 800 ºC.En el presente trabajo se incluyen los resultados de la resistencia a la penetración de cloruros de morteros de Cemento Portland Ordinario (OPC adicionados con un caolín colombiano sometido a tratamiento térmico en un rango de temperaturas entre 600 y 800 °C. Los productos del tratamiento térmico, metacaolín (MK, son incorporados en mezclas de morteros de OPC en proporciones del 10 y 20% en relación al peso del cemento. Se comparan sus características físico-químicas, entre las cuales se incluye la microestructura de poros evaluada por la técnica de porosimetría de mercurio, con la absorción capilar y la permeabilidad a cloruros. Se concluye que las muestras adicionadas con un 20% del material tratado térmicamente a 800 °C presentan el mejor desempeño en sus propiedades finales.

  3. Bacterial cellulose–kaolin nanocomposites for application as biomedical wound healing materials

    International Nuclear Information System (INIS)

    Wanna, Dwi; Alam, Parvez; Alam, Catharina; Toivola, Diana M

    2013-01-01

    This short communication provides preliminary experimental details on the structure–property relationships of novel biomedical kaolin–bacterial cellulose nanocomposites. Bacterial cellulose is an effective binding agent for kaolin particles forming reticulated structures at kaolin–cellulose interfaces and entanglements when the cellulose fraction is sufficiently high. The mechanical performance of these materials hence improves with an increased fraction of bacterial cellulose, though this also causes the rate of blood clotting to decrease. These composites have combined potential as both short-term (kaolin) and long-term (bacterial cellulose) wound healing materials. (paper)

  4. Flotation of kaolinite from tailings of kaolin-washing plants by cationic collectors

    Directory of Open Access Journals (Sweden)

    Barani Kianoush

    2016-01-01

    Full Text Available Traditional processing of kaolin is achieved by dispersion of the mined ore and classification by means of multistage hydrocyclones. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back to the quarry. In this research recovery of kaolinite from tailings of the Zonoupz kaolin washing plant, which is located in Iran, was investigated by cationic flotation. Flotation experiments showed that flotation of kaolinite from tailings was much better in an acidic than in an alkaline medium containing cationic collectors.

  5. Adsorption of U(VI) onto kaolin studied by batch method

    International Nuclear Information System (INIS)

    Hongxia Zhang; Zhi Liu; Peizhuo Hu; Tonghuan Liu; Wangsuo Wu

    2013-01-01

    Adsorption of U(VI) on purified kaolin was studied by batch methods under ambient conditions, including contact time, pH, fulvic acid, etc. Three kinetic models were used to model the kinetic adsorption which was very well described by the pseudo-second-order rate equation, and the activation energy of adsorption was 52.20 kJ/mol. The Freundlich and Dubinin-Radushkevich models fitted the experimental data better than the Langmuir model for the adsorption and desorption isotherms. The thermodynamic parameters indicated that the adsorption of U(VI) on kaolin was an endothermic and spontaneous process. (author)

  6. Microstructural analysis of ceramic masses with waste kaolin addition for the red ceramic production

    International Nuclear Information System (INIS)

    Vida, Talita Almeida; Fagury Neto, Elias; Rabelo, Adriano Alves

    2010-01-01

    Incorporating reject industrial ceramic mixtures has proved viable in the reduction of environmental liabilities. In this study, we sought to study the potential use of ceramic formulations with the addition of tailings from the production of kaolin clay to the region of the city of Maraba-PA. Formulations were obtained with two clays of this region with the addition of up to 60% by weight of kaolin waste. The microstructural analyses were carried out from the preparation of specimens that were sintered at 1000 and 1200 °C with level 3 hours. The samples prepared were used to observe the microstructure by optical microscope, to determine the constituents of each formulation after burning. And later analysis was performed X-rays diffraction, to quantify the phases present. It was observed that increasing the content of the mixture of kaolin clay caused the reaction of kaolinite forming the primary mullite from 1000 ° C. For a firing temperature around 1200 ° C showed the presence of mullite even the addition of 20% kaolin, noting also the presence of secondary kaolinite. (author)

  7. synthesis of zeolite-a using kaolin samples from darazo, bauchi ...

    African Journals Online (AJOL)

    henry mgbemere

    ekpeikenna@gmail.com, ... 13]. Kaolin is a naturally occurring mineral of the clay family and may contain a ..... Properties," World Journal of Nano Science and ... Treatment on Kankara Kaolinite," Opticon1826, vol. 15, pp. 1-5, 2013. .... 36(2) 444-451.

  8. Fire performance of fiber board coated with nano kaolin-clay film

    Science.gov (United States)

    Zhijia Liu; John F. Hunt; Zhiyong Cai

    2013-01-01

    Fiberboard is a common interior material used both in China and the United States of America. The increase in demand for interior materials has raised concerns regarding combustibility of the materials. The pyrolysis characteristics of fiber, phenolic resin (PF), and nano kaolin-clay (NK) were investigated using thermogravimetry. The fire performances of samples coated...

  9. Evaluation of the potential of waste processing of secondary kaolin of Para for use in porcelain

    International Nuclear Information System (INIS)

    Junior, V.G.L.; Fernandes, L.L.; Fagury Neto, E.; Rabelo, A.A.

    2012-01-01

    The kaolin waste evaluated is characterized as secondary due be coming from the steps of centrifugation, magnetic separation, bleaching and filtering, which gives a ratio which provides a significant residue, about 26% of their gross, that is intended for embankments. This study aimed to evaluate the potential of reusing the kaolin waste processing from Imerys RCC in the region of Barcarena (PA) in formulation of ceramic bodies for porcelain tiles production, seeking to property of maximum water absorption of 0.5 % for this type of product. The residue from the production of kaolin had been previously characterized by X-ray diffraction and there is a significant amount of kaolinite concentration. After the ceramic processing to obtain the test specimens with different amounts of residue replacing the kaolin, these were sintered using 1200, 1220 and 1240 °C for 2 hours. The formulations were evaluated by water absorption, linear firing shrinkage and modulus of rupture at a three-point bending setup of the pieces produced. (author)

  10. Use of kaolin waste for production os soil-lime blocks

    International Nuclear Information System (INIS)

    Anjos, C.M. dos; Neves, G.A.

    2011-01-01

    There is an evident growth in waste generation over the last decades, especially in developing countries. The mining industry produces large quantities and different kinds and levels of dangerousness, such as the kaolin processing industry, which produces waste based on silica, mica and kaolinite. Disposal of this material in an inappropriate location causes significant environmental impacts, which could be minimized with the use of waste as raw material for use in construction. This paper has as main objective to study the incorporation of the kaolin processing waste into soil-lime. The residues of kaolin were calcined at a temperature of 800 ° C for evaluation of pozzolanic activity. Raw materials and conventional alternatives were characterized by means of test particle size analysis by laser diffraction, chemical analysis, X-ray diffraction. Then, blocks conventional soil-lime and soil-lime with the introduction of residual kaolin in proportions of 10%, 20%, 30% and 40% were cast and cured in a moist chamber for periods of 28, 60 and 90 days. The technological tests of compressive strength results obtained within the specifications of the ABNT. The best results were for 90 days of healing and 20% residue. (author)

  11. Electrochemical oxidation of pulp and paper making wastewater assisted by transition metal modified kaolin

    International Nuclear Information System (INIS)

    Wang Bo; Gu Lin; Ma Hongzhu

    2007-01-01

    The electrochemical oxidation of pulp and paper making wastewater assisted by transition metal (Co, Cu) modified kaolin in a 200 ml electrolytic batch reactor with graphite plate as electrodes was investigated. H 2 O 2 , which produced on the surface of porous graphite cathode, would react with the catalysts to form strong oxidant (hydroxyl radicals) that can in turn destruct the pollutants adsorbed on the surface of kaolin. The transition metal (Co, Cu) modified kaolin was also characterized by XRD and SEM before and after the modification and the results showed that the transition metals were completely supported on kaolin and formed a porous structure with big BET surface. The mechanism was proposed on the basis of XPS analysis of the catalyst after the degradation process. Series of experiments were also done to prove the synergetic effect of the combined oxidation system and to find out the optimal operating parameters such as initial pH, current density and amount of catalyst. From the results it can be founded that when the initial pH was at 3, current density was 30 mA cm -2 ; catalyst dose was 30 g dm -3 , COD (chemical oxygen demand) removal could reach up to 96.8% in 73 min

  12. Removal of heavy metals from kaolin using an upward electrokinetic soil remedial (UESR) technology

    International Nuclear Information System (INIS)

    Wang, J.-Y.; Huang, X.-J.; Kao, Jimmy C.M.; Stabnikova, Olena

    2006-01-01

    An upward electrokinetic soil remedial (UESR) technology was proposed to remove heavy metals from contaminated kaolin. Unlike conventional electrokinetic treatment that uses boreholes or trenches for horizontal migration of heavy metals, the UESR technology, applying vertical non-uniform electric fields, caused upward transportation of heavy metals to the top surface of the treated soil. The effects of current density, treatment duration, cell diameter, and different cathode chamber influent (distilled water or 0.01 M nitric acid) were studied. The removal efficiencies of heavy metals positively correlated to current density and treatment duration. Higher heavy metals removal efficiency was observed for the reactor cell with smaller diameter. A substantial amount of heavy metals was accumulated in the nearest to cathode 2 cm layer of kaolin when distilled water was continuously supplied to the cathode chamber. Heavy metals accumulated in this layer of kaolin can be easily excavated and disposed off. The main part of the removed heavy metals was dissolved in cathode chamber influent and moved away with cathode chamber effluent when 0.01 M nitric acid was used, instead of distilled water. Energy saving treatment by UESR technology with highest metal removal efficiencies was provided by two regimes: (1) by application of 0.01 M nitric acid as cathode chamber influent, cell diameter of 100 mm, duration of 18 days, and constant voltage of 3.5 V (19.7 kWh/m 3 of kaolin) and (2) by application of 0.01 M nitric acid as cathode chamber influent, cell diameter of 100 cm, duration of 6 days, and constant current density of 0.191 mA/cm 2 (19.1 kWh/m 3 of kaolin)

  13. Comparative studies on physico-mechanical properties of composite materials of low density polyethylene and raw/calcined kaolin

    Directory of Open Access Journals (Sweden)

    Amit Mallik

    2015-06-01

    Full Text Available The paper describes the preparation of the composite materials of low density polyethylene (LDPE as the base mixed separately with raw kaolin and the same calcined at 800 °C under the same variation in weight percentage using single-screw extruder and a mixing machine operated at a temperature between 190 and 200 °C. Some of the mechanical and physical properties such as Young's modulus, elongation at break, shore hardness and water absorption were determined at different weight fractions of filler (0, 2, 7, 10 and 15%. It was found that the addition of filler increases the mechanical properties. Absorption test was done in water at different immersion times for different composites. The degree of water absorption of composite materials was found to decrease with increasing wt% of kaolin filler (0–15% according to Fick's law. Calcined kaolin produces better mechanical properties than raw kaolin.

  14. Why Wet Kaolin can be used as a Crustal Analog and its Application to Fault Evolution at Restraining Bends

    Science.gov (United States)

    Cooke, M. L.; van der Elst, N.; Schottenfeld, M. T.

    2010-12-01

    To simulate geologic deformation on observable time and length scales within the lab, a subset of analog modelers have used wet kaolin. Unlike the more often used sand, wet kaolin beautifully exhibits detailed fault structures. Furthermore, faults within the kaolin are more readily reactivated than those in sand. The low plasticity of kaolin (compared to other clays) gives it low shear strength. Consequently, the clay is a suitable analog material if we assume that the wet kaolin deforms by coulomb frictional failure. Koalin generally deforms as a Bingham solid and exhibits more complex deformation than the perfectly plastic behavior assumed with Coulomb failure. We performed fall cone and rheometric tests on wet kaolin to refine our quantitative understanding of its rheology. We use North American wet kaolin with density 1.65-1.7 g/cm3 and water content of 37.5-38.5%. The fall cone tests reveal that the undrained shear strength (100-160 Pa) is greater than previously measured with a viscometer. The rheometer tests show that the wet koalin exhibits many of the same properties of crustal materials including: 1) elastic behavior at low strains, 2) stress relaxation at near-failure strains, 3) creep under static load, 4) yield strength sensitive to strain rate and 5) rate and state dependent failure. Armed with quantitative values for this complex deformation, we can better scale the length and strain rate of the wet koalin experiments to specific crustal settings. Experiments of deformation around restraining bends show features very similar to those found in natural examples. The detailed fault structures produced in the wet kaolin can be analyzed to understand the evolution of active faulting at restraining bends.

  15. Long-Chain Diacrylate Crosslinkers and Use of PEG Crosslinks in Poly(potassium acrylate-acrylic acid/Kaolin Composite Superabsorbents

    Directory of Open Access Journals (Sweden)

    Koroush Kabiri

    2013-01-01

    Full Text Available Long-chain diacrylate crosslinkers based on linear α,ω-diols were synthesized and characterized using FTIR and 1H NMR spectroscopy. The highest reaction yield (99.5% was due to polyethylene glycol diacrylate 1000 (PEGDA-1000. Then, kaolin-containing poly(potassium acrylate-acrylic acid superabsorbent composites and kaolin-free counterparts were synthesized using PEGDA-1000.The effect of the crosslinker concentration on swelling, rheological and thermo-mechanical properties was investigated. Absorption capacity of the composite hydrogels (having ~38% kaolin was unexpectedly higher than that of kaolin-free hydrogels. This was attributed to an interfering effect of kaolin during the polymerization. Glass transition temperature was increased with crosslinker concentration enhancement and addition of kaolin up to about 10oC and 28oC, respectively. Making such K-containing superabsorbents may be taken as an effective action to achieve more durable and cheaper superabsorbents for agricultural uses.

  16. New organophilic kaolin clays based on single-point grafted 3-aminopropyl dimethylethoxysilane.

    Science.gov (United States)

    Zaharia, A; Perrin, F-X; Teodorescu, M; Radu, A-L; Iordache, T-V; Florea, A-M; Donescu, D; Sarbu, A

    2015-10-14

    In this study, the organophilization procedure of kaolin rocks with a monofunctional ethoxysilane- 3 aminopropyl dimethyl ethoxysilane (APMS) is depicted for the first time. The two-step organophilization procedure, including dimethyl sulfoxide intercalation and APMS grafting onto the inner hydroxyl surface of kaolinite (the mineral) layers was tested for three sources of kaolin rocks (KR, KC and KD) with various morphologies and kaolinite compositions. The load of APMS in the kaolinite interlayer space was higher than that of 3-aminopropyl triethoxysilane (APTS) due to the single-point grafting nature of the organophilization reaction. A higher long-distance order of kaolinite layers with low staking was obtained for the APMS, due to a more controllable organiphilization reaction. Last but not least, the solid state (29)Si-NMR tests confirmed the single-point grafting mechanism of APMS, corroborating monodentate fixation on the kaolinite hydroxyl facets, with no contribution to the bidentate or tridentate fixation as observed for APTS.

  17. Study of the sodalite Bayer synthesis process from reject of kaolin of the Amazon region, Brazil

    International Nuclear Information System (INIS)

    Maia, A.A.B.; Neves, R.F.; Angelica, R.S.; Pöllmann, H.

    2011-01-01

    This work presents an application for the kaolin rejects from Amazonia through the synthesis of sodalite, in addition, the series of sodalites was synthesized with the same conditions of the Bayer process to understand and control their formation when necessary. These tailings are generated by companies located in the state of Para and are mainly composed of kaolinite, thus forming an excellent starting material for the production of zeolites. The synthesis process was carried out in autoclaves and two synthesis temperatures, 150 and 200 deg C, were evaluated, the same ones used in the Bayer process. The anions used in the reaction mixture to obtain the sodalite series were: carbonate chloride and sulfate, and NaOH solution was used as the sodium source. Sodalite was produced in all the synthesis conditions, showing that through the kaolin rejects from the Amazon it was possible to study the sodalite synthesis process.

  18. Thermodynamic analysis of stability in iron removal from kaolin by using oxalic acid

    Directory of Open Access Journals (Sweden)

    C. Ocampo-López

    2013-06-01

    Full Text Available The graphical representation of global stability for a system, or Pourbaix diagram, was constructed to perform a thermodynamic study of iron removal from kaolin using oxalic acid as an oxidant. To do this the free energies of formation of the oxalate complex of the system were calculated, and it was found that the more stable specie is Fe(C2O43-3, with a calculated free energy of formation of -3753.88 kcal/mol. Thermodynamic stability functions were estimated for the system as a function of pH and Eh known as potential of oxide reduction. It was built a global stability diagram for the removal system; it showed that the specie trioxalate Fe(C2O43-3 is the only oxalate in equilibrium with other compounds associated with the removal of iron in kaolin.

  19. Determination of the zero point of charge of kaolin waste from the Northeast of Para, BR

    International Nuclear Information System (INIS)

    Pinto, R.L.S.; Maia, R.F.S.; Felipe, A.M.P.F.

    2012-01-01

    The Para contributes with more than 50% of national production of kaolin of which 12.5% correspond to the waste generated, which has similar composition to benefited kaolin, can be used as adsorbent of heavy metals. The viscosity influences the design of equipment that can reuse that waste. The pH changes the pulp viscosity and the determination of the zero point of charge can estimate this variation. This study analyzes the influence of pH on the pulp rheology by the determination of the zero point of charge. Tests were made by Scanning Electron Microscopy, Energy Dispersive Spectroscopy, potentiometric titulation and rheological analysis. The results showed zero point of charge equal to 3.7 and confirmed that the viscosity increase at pH values near the zero point of charge and decrease at pH values away from this. (author)

  20. Facile Fabrication of a Hierarchical Superhydrophobic Coating with Aluminate Coupling Agent Modified Kaolin

    Directory of Open Access Journals (Sweden)

    Hui Li

    2013-01-01

    Full Text Available A superhydrophobic coating was fabricated from the dispersion of unmodified kaolin particles and aluminate coupling agent in anhydrous ethanol. Through surface modification, water contact angle of the coating prepared by modified kaolin particles increased dramatically from 0° to 152°, and the sliding angle decreased from 90° to 3°. Scanning electron microscopy was used to examine the surface morphology. A structure composed of micro-nano hierarchical component, combined with the surface modification by aluminate coupling agent which reduced the surface energy greatly, was found to be responsible for the superhydrophobicity. The method adopted is relatively simple, facile, and cost-effective and can potentially be applied to large water-repellent surface coatings.

  1. Application of molybdenum and phosphate modified kaolin in electrochemical treatment of paper mill wastewater

    International Nuclear Information System (INIS)

    Ma Hongzhu; Wang Bo; Wang Ying

    2007-01-01

    Pulp and paper mill wastewater is characterized by very high chemical oxygen demand (COD) values that inhibit the activity of microorganisms during biological oxidations. The electrochemical degradation of pulp and paper mill wastewater catalyzed by molybdenum and phosphate (Mo-P) modified kaolin with graphite as anode and cathode was investigated. The catalyst was characterized by XRD, XPS and SEM spectra and the effects of pH, metal ion and introduction of NaCl on the efficiency of the electrochemical degradation process were also studied. It was found out that the modified kaolin loaded with Fe 3+ had higher electrochemical catalytic activity in the electrochemical degradation of paper mill wastewater at pH 4. A 96% COD removal efficiency was obtained in 40 min of electrochemical treatment of the wastewater at current density 30 mA cm -2 . A possible mechanism for degradation of the mill wastewater constituents was also proposed

  2. Comparing Kaolin and Pinolene to Improve Sustainable Grapevine Production during Drought

    OpenAIRE

    Brillante, Luca; Belfiore, Nicola; Gaiotti, Federica; Lovat, Lorenzo; Sansone, Luigi; Poni, Stefano; Tomasi, Diego

    2016-01-01

    Viticulture is widely practiced in dry regions, where the grapevine is greatly exposed to water stress. Optimizing plant water use efficiency (WUE) without affecting crop yield, grape and wine quality is crucial to limiting use of water for irrigation and to significantly improving viticulture sustainability. This study examines the use in vineyards of particle film technology (engineered kaolin) and compares it to a film-forming antitranspirant (pinolene), traditionally used to limit leaf wa...

  3. The efficacy of kaolin clay in reducing the duration and severity of `heat' diarrhea in foals

    OpenAIRE

    PIESZKA, MAGDALENA; LUSZCZYNSKI, JAROSLAW; HEDRZAK, MAGDALENA; GONCHAROVA, KATERINA; PIERZYNOWSKI, STEFAN G.

    2016-01-01

    'Heat' diarrhea in foals is an onerous but not life-threatening ailment, which indicates that it may be of osmotic origin. This was confirmed by a successful attempt, presented in this paper, to alleviate the severity and duration of foal heat diarrhea with the use of a typical absorbent, kaolin clay, as a feed additive, usually applied in feed production as an anticaking agent. Based on the present results, it can be concluded that treatment of foals maintained on different stud fa...

  4. Investigation on the effect of sintering temperature on kaolin hollow fibre membrane for dye filtration.

    Science.gov (United States)

    Mohtor, Nur Hamizah; Othman, Mohd Hafiz Dzarfan; Ismail, Ahmad Fauzi; Rahman, Mukhlis A; Jaafar, Juhana; Hashim, Nur Awanis

    2017-07-01

    Despite its extraordinary price, ceramic membrane can still be able to surpass polymeric membrane in the applications that require high temperature and pressure conditions, as well as harsh chemical environment. In order to alleviate the high cost of ceramic material that still becomes one of the major factors that contributes to the high production cost of ceramic membrane, various attempts have been made to use low cost ceramic materials as alternatives to well-known expensive ceramic materials such as alumina, silica, and zirconia in the fabrication of ceramic membrane. Thus, local Malaysian kaolin has been chosen as the ceramic material in this study for the preparation of kaolin hollow fibre membrane since it is inexpensive and naturally abundant in Malaysia. Due to the fact that the sintering process plays a prominent role in obtaining the desired morphology, properties, and performances of prepared ceramic membrane, the aim of this work was to study the effect of different sintering temperatures applied (ranging from 1200 to 1500 °C) in the preparation of kaolin hollow fibre membrane via dry/wet phase inversion-based spinning technique and sintering process. The morphology and properties of membrane were then characterised by SEM, AFM, FTIR, XRD, and three-point bending test, while the performances of membrane were investigated by conducting water permeation and Reactive Black 5 (RB5) dye rejection tests. From the experimental results obtained, the sintering temperature of 1400 °C could be selected as the optimum sintering temperature in preparing the kaolin hollow fibre membrane with the dense sponge-like structure of separation layer that resulted in the good mechanical strength of 70 MPa with the appreciable water permeation of 75 L/h m 2  bar and RB5 rejection of 68%.

  5. PES-Kaolin Mixed Matrix Membranes for Arsenic Removal from Water.

    Science.gov (United States)

    Marino, Tiziana; Russo, Francesca; Rezzouk, Lina; Bouzid, Abderrazak; Figoli, Alberto

    2017-09-30

    The aim of this work was the fabrication and the characterization of mixed matrix membranes (MMMs) for arsenic (As) removal from water. Membrane separation was combined with an adsorption process by incorporating the kaolin (KT2) Algerian natural clay in polymeric membranes. The effects of casting solution composition was explored using different amounts of polyethersufone (PES) as a polymer, polyvinyl-pyrrolidone (PVP K17) and polyethylene glycol (PEG 200) as pore former agents, N -methyl pyrrolidone (NMP) as a solvent, and kaolin. Membranes were prepared by coupling Non-solvent Induced Phase Separation and Vapour Induced Phase Separation (NIPS and VIPS, respectively). The influence of the exposure time to controlled humid air and temperature was also investigated. The MMMs obtained were characterized in terms of morphology, pore size, porosity, thickness, contact angle and pure water permeability. Adsorption membrane-based tests were carried out in order to assess the applicability of the membranes produced for As removal from contaminated water. Among the investigated kaolin concentrations (ranging from 0 wt % to 5 wt %), a content of 1.25 wt % led to the MMM with the most promising performance.

  6. Characterization of ceramic masses using raw material of Para, Brazil: kaolin in natura

    International Nuclear Information System (INIS)

    Vida, T.A.; Facury Neto, E.; Rabelo, A.A.

    2009-01-01

    The incorporation rejects to the mixtures has if shown viable in the reduction of the environmental liability and for the obtaining of a better quality of the ceramic mass. In the present work, is tried to study the potentiality of the use of ceramic formulations with the addition of kaolin in natura to the clays. Formulations with two clays of the area of the municipal district of Maraba with addition of up to 60% in kaolin weight were prepared and characterized. For the determination of the physical and mechanical properties proof bodies were made by prensagem uniaxial and later burned in temperature from 900 to 1200 deg C with landing of 3 hours. The raw materials were characterized through diffraction of rays X (DRX) and thermogravimetric analysis. The proof bodies prepared were used for determination of the lineal retraction (RL), absorption of water, apparent porosity, apparent density, loss to the fire and rupture module the flexing. The results were satisfactory for the smallest kaolin tenors in the ceramic mass, and the mass with 20% presented rupture module elevated, in the temperature of 1200 deg C. (author)

  7. Correlation between hardness and water absorption properties of Saudi kaolin and white clay geopolymer coating

    Science.gov (United States)

    Ramasamy, Shamala; Abdullah, Mohd Mustafa Al Bakri; Huang, Yue; Hussin, Kamarudin; Wang, Jin; Shahedan, Noor Fifinatasha

    2017-09-01

    Geopolymer is an uprising technology that is being studied worldwide. Geopolymer raw materials are basically aluminosilicate source materials. However, this technology is yet to infiltrate into pipelines and coating industries which initiated our research idea. The idea of creating universal geopolymer based coating material is mainly to help oil and gas industry reduce its maintenance cost. Kaolin based geopolymer paste was coated on glass reinforced epoxy (GRE) substrates which are majorly used as pipeline material in the oil and gas industry at Saudi Arabia. Kaolin and white clay was chosen as raw material to study the possibilities of utilizing underused aluminosilicate raw materials for geopolymer coating. To obtain suitable formulation, Na2SiO3/NaOH ratio was varied from 0.40 untill 0.60 while other parameters such as solid/liquid ratio and NaOH molarity were kept constant at values as per previous works. Geopolymer coated GRE substrates were then subjected to water absorption, flexural strength and hardness test to validate our findings. Water absorption is a crucial test as for coating materials which justifies the pratical usability of the coating product. Upon testing, kaolin and white clay based geopolymer coating each shows promising properties at Na2SiO3/NaOH ratio of 0.45 and 0.50 each.

  8. Influence of Kaolin in Fly Ash Based Geopolymer Concrete: Destructive and Non-Destructive Testing

    Science.gov (United States)

    Yahya, Z.; Abdullah, M. M. A. B.; Ramli, N. Mohd; Burduhos-Nergis, D. D.; Razak, R. Abd

    2018-06-01

    Development of geopolymer concrete is mainly to reduce the production of ordinary Portland cement (OPC) that adverse the natural effect. Fly ash is a by-product collected from electrical generating power plant which resulted from burning pulverized coal. Since fly ash is waste materials, it can be recycled for future advantages particularly as pozzolanic materials in construction industry. This study focused on the feasibility of fly ash based geopolymer concrete to which kaolin has been added. The main constituents of geopolymer production for this study were class F fly ash, sodium silicate and sodium hydroxide (NaOH) solution. The concentration of NaOH solution was fixed at 12 Molar, ratio of fly ash/alkaline activator and sodium silicate/NaOH fixed at 1.5 and 2.5, respectively. Kaolin was added in range 5% to 15% from the mass of fly ash and all the samples were cured at room temperature. Destructive and non-destructive test were performed on geopolymer concrete to evaluate the best mix proportions that yield the highest strength as well as the quality of the concrete. Compressive strength, flexural strength, rebound hammer and ultrasonic pulse velocity (UPV) result have been obtained. It shown that 5% replacement of kaolin contributed to maximum compressive strength and flexural strength of 40.4 MPa and 12.35 MPa at 28 days. These result was supported by non-destructive test for the same mix proportion.

  9. Elaboration and characterization of mullite-anorthite-albite porous ceramics prepared from Algerian kaolin

    International Nuclear Information System (INIS)

    Rouabhia, F.; Nemamcha, A.; Moumeni, H.

    2018-01-01

    Mullite-anorthite-albite porous ceramic materials were successfully prepared by a solid-state reaction between kaolin clay and two different additives (CaCO 3 and Na 2 CO 3 ). The starting raw material was characterized by X-ray fluorescence, X-ray diffraction (XRD) and dynamic light scattering techniques. The effect of CaCO 3 and Na 2 CO 3 concentration (10 to 70 wt%) on structure, morphology and thermal properties of the obtained ceramics was investigated by XRD, scanning electron microscopy and differential scanning calorimetry (DSC) techniques. The XRD patterns showed that mullite (3Al 2 O 3 .2SiO 2 ), anorthite (CaO.Al 2 O 3 .2SiO 2 ) and albite (Na 2 O.Al 2 O 3 .6SiO 2 ) were the main crystalline phases present in the materials. The morphology investigation revealed the porous texture of obtained ceramics characterized by the presence of sponge-like structure mainly due to the additive decomposition at high temperatures. The DSC results confirm the presence of four temperature regions related to the kaolin thermal transformations and the formation of minerals. The temperature and enthalpy of mineral formation are additive concentration dependent. As a result, the optimal content of additives which allowed the coexistence of the three phases, a spongelike morphology, and high porosity without cracks corresponded to 15 wt% CaCO 3 , 15 wt% Na 2 CO 3 , and 70 wt% kaolin. (author)

  10. DMC-grafted cellulose as green-based flocculants for agglomerating fine kaolin particles

    Directory of Open Access Journals (Sweden)

    Meng Li

    2018-04-01

    Full Text Available Novel cellulose based flocculants C-g-P (DMC with various chain architectures are synthesized through a situ graft copolymerization. The cationic ammonium chloride group (DMC is grafted onto cellulose by two separate inverse emulsion polymerization with γ-methacryloxypropyl trimethoxy silane (KH-570 and double bond addition reactions, which is a new and simple method to employ KH-570 as a bridge for the connection of cellulose matrix and DMC group. The effects of pH, flocculant dose, standing time on turbidity of kaolin suspensions and particle sizes have been studied systematically. In addition, the response surface methodology (RSM study confirms that PAC and C-g-P (DMC have synergy in turbidity removal with a higher removal efficiency of 98.32%. Moreover, C-g-P (DMC 1 has higher removal efficiency with 96.5% at a low dosage of 0.6 mg L−1 and better floc properties than C-g-P (DMC 2 and C-g-P (DMC 3, suggesting that the length and quantity of cationic branch chains play a crucial role in Kaolin flocculation due to their dramatically enhanced bridging effects. Keywords: Cellulose, Cationic flocculant, Inverse emulsion polymerization, Kaolin suspension

  11. An evaluation of soluble cations and anions on the conductivity and rate of flocculation of kaolins

    Science.gov (United States)

    Fulton, Deborah Lee

    1998-10-01

    The focus of this project was to learn how ionic concentrations and their contributions to electric conductivity influence the flocculation behavior of kaolin/water suspensions. Sodium silicate, calcium chloride, and magnesium sulfate were used as chemical additives. The specific surface areas, particle size distributions, and methylene blue indices for two kaolins were measured. The SSA and MBI for these kaolins indicated that they possessed inherent differences in SSA and flocculation behaviors. Rheological studies were also performed. Testing included simultaneous gelation, deflocculation, and pH tests. Viscosity, pH, temperature, and chemical additive concentrations were monitored at each point. Testing was performed at 45/55 wt% solids. Effects of additions of various levels of deflocculant and flocculant to each of the kaolin/water suspensions were studied by making several suspensions from each kaolin. The concentrations of dispersant, and flocculant levels and types were varied to produce suspensions with different chemical additive "histories," but all with similar final apparent viscosities. Slurry filtrates were analyzed for conductivity, pH, temperature, and ion concentrations of (Al3+, Fe2+,3+, Ca 2+, Mg+, Na+, SO4 2--, and Cl--). Plastic properties were calculated to determine how variations in suspension histories affected conductivities, pH, and detectable ion contents of the suspensions. These analyses were performed on starting slurries which were under-, completely-, and over-deflocculated before further additions of flocculants and deflocculant were added to tune the slurries to the final, constant, target viscosity. Results showed that rates of flocculation and conductivities increased as concentrations of ions increased. By increasing conductivity correlations with increases in flocculation occurs, which yields higher rates of buildup, or RBU [1]. This is the single most important slip control property in the whitewares industry. Shear

  12. Application of 3D Electrical Resistivity Tomography As A Tool for Mapping Subsurface Cavities in a Kaolin Mining Site at Kankara in North Central Nigeria.

    Science.gov (United States)

    Eshimiakhe, D.; Jimoh, R.

    2017-12-01

    A Kaolin mining site at Dajin Gwanma in north central Nigeria was investigated to determine the possibility of using 3D ERT to detect subsurface voids created due to mining of kaolin deposit and to perhaps suggest areas prone to subsidence. This study was undertaken on conceptual resistivity model that subsurface voids characterized by higher or lower resistivity than the host, depending on weather the void is in-filled water or not. The data collection was carried out with Terrameter SAS 4000 and ES 464 electrode selector equipment. Dipole-dipole configuration at electrode spacing of 5m was used to acquire the data along parallel profiles laid at equal interval in the study area. While the acquired data along each profile were inverted with 2D algorithm, a script file was created to collate the 2D data set into a 3D format and subsequently inverted using 3D algorithm. A volumetric resistivity model block of the study area was also created using the voxler 4 software. The results show that the voids are characterized by high resistivity (950Ωm-2500Ωm) at depth of between 0-4m and low resistivity (10Ωm-100Ωm) at a depth of 5-30m indicating both air-filled and water-filled voids respectively. The study shows that the voids increase in dimension with depth in NW-SE direction, suggesting that the voids are trending most probably along vertical bedrock joints. It also suggest that voids may overtime grow large enough that the overlying top soil can no longer bridge it, leading to its collapse.

  13. Effects of Kaolin Application on Light Absorption and Distribution, Radiation Use Efficiency and Photosynthesis of Almond and Walnut Canopies

    Science.gov (United States)

    Rosati, Adolfo; Metcalf, Samuel G.; Buchner, Richard P.; Fulton, Allan E.; Lampinen, Bruce D.

    2007-01-01

    Background and Aims Kaolin applied as a suspension to plant canopies forms a film on leaves that increases reflection and reduces absorption of light. Photosynthesis of individual leaves is decreased while the photosynthesis of the whole canopy remains unaffected or even increases. This may result from a better distribution of light within the canopy following kaolin application, but this explanation has not been tested. The objective of this work was to study the effects of kaolin application on light distribution and absorption within tree canopies and, ultimately, on canopy photosynthesis and radiation use efficiency. Methods Photosynthetically active radiation (PAR) incident on individual leaves within the canopy of almond (Prunus dulcis) and walnut (Juglans regia) trees was measured before and after kaolin application in order to study PAR distribution within the canopy. The PAR incident on, and reflected and transmitted by, the canopy was measured on the same day for kaolin-sprayed and control trees in order to calculate canopy PAR absorption. These data were then used to model canopy photosynthesis and radiation use efficiency by a simple method proposed in previous work, based on the photosynthetic response to incident PAR of a top-canopy leaf. Key Results Kaolin increased incident PAR on surfaces of inner-canopy leaves, although there was an estimated 20 % loss in PAR reaching the photosynthetic apparatus, due to increased reflection. Assuming a 20 % loss of PAR, modelled photosynthesis and photosynthetic radiation use efficiency (PRUE) of kaolin-coated leaves decreased by only 6·3 %. This was due to (1) more beneficial PAR distribution within the kaolin-sprayed canopy, and (2) with decreasing PAR, leaf photosynthesis decreases less than proportionally, due to the curvature of the photosynthesis response-curve to PAR. The relatively small loss in canopy PRUE (per unit of incident PAR), coupled with the increased incident PAR on the leaf surface on

  14. Novel kaolin/polysiloxane based organic-inorganic hybrid materials: Sol-gel synthesis, characterization and photocatalytic properties

    Science.gov (United States)

    dos Reis, Glaydson Simões; Lima, Eder Cláudio; Sampaio, Carlos Hoffmann; Rodembusch, Fabiano Severo; Petter, Carlos Otávio; Cazacliu, Bogdan Grigore; Dotto, Guillherme Luiz; Hidalgo, Gelsa Edith Navarro

    2018-04-01

    New hybrid materials using kaolin and the organosilicas methyl-polysiloxane (MK), methyl-phenyl-polysiloxane (H44), tetraethyl-ortho-silicate (TEOS) and 3-amino-propyl-triethoxysilane (APTES) were obtained by sol-gel process. These materials presented specific surfaces areas (SBET) in the range of 20-530 m2 g-1. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed remarkable differences between the kaolin and hybrid structures. Thermogravimetric analysis (TGA) revealed that the hybrid materials presented higher thermal stability when compared with their precursors. The electronic properties of the materials were also studied by Ultraviolet-Visible Diffuse Reflectance Absorption (DRUV) and Diffuse Reflectance spectroscopy (DR), where a new absorption band was observed located around 400-660 nm. In addition, these materials exhibit a decrease in DR from 30% to 70% in the blue-cyan green region and are significantly more transparent in the UV region than the kaolin, which could be useful for photocatalysis applications. These results show that the electronic structure of the final material was changed, indicating a significant interaction between the kaolin and the respective silica derivative. These findings support the main idea of the hybridization afforded by pyrolysis between kaolin and organosilica precursors. In addition, as a proof of concept, these hybrid materials were successfully employed as photocatalyst in the photoreduction of Cr(VI) to Cr(III).

  15. Synthesis of zeolite using as precursor reject of kaolin of the Amazon Region: application as an adsorbent in gas drying

    International Nuclear Information System (INIS)

    Morais, M.R.C.; Santana, D.L. de; Martelli, M.C.; Neves, R.F.

    2011-01-01

    Zeolites have large variety of technological applications, accounting for an increasing interest in various industries. In the State of Para, located three industries from kaolin for paper, where large amounts of waste are stored in ponds in becoming environmental problem. This work aims to develop a process for obtaining a zeolite P from the kaolin waste as the starting material. The synthesis was performed with kaolin waste from Capim River region, calcined at 700 ° C for 2 h, and reacted in the presence of aqueous NaOH and diatomite (silica source supplement), and the process hydrothermal temperature of 110 ° C for varied times. The characterization of the starting material and the synthesized materials was carried out using XRD and SEM. At the end of the experiment, the zeolite P synthesized was tested for moisture adsorption and was effective for this purpose. (author)

  16. Comparing Kaolin and Pinolene to Improve Sustainable Grapevine Production during Drought.

    Science.gov (United States)

    Brillante, Luca; Belfiore, Nicola; Gaiotti, Federica; Lovat, Lorenzo; Sansone, Luigi; Poni, Stefano; Tomasi, Diego

    2016-01-01

    Viticulture is widely practiced in dry regions, where the grapevine is greatly exposed to water stress. Optimizing plant water use efficiency (WUE) without affecting crop yield, grape and wine quality is crucial to limiting use of water for irrigation and to significantly improving viticulture sustainability. This study examines the use in vineyards of particle film technology (engineered kaolin) and compares it to a film-forming antitranspirant (pinolene), traditionally used to limit leaf water loss, and to an untreated control. The trial was carried out under field conditions over three growing seasons, during which moderate to very severe plant water stress (down to -1.9 MPa) was measured through stem water potential. Leaf stomatal conductance (gs) and photosynthesis rate (An) were measured during the seasons and used to compute intrinsic WUE (WUEi, defined as An/gs ratio). Leaf temperature was also recorded and compared between treatments. Bunch quantity, bunch and berry weight, sugar accumulation, anthocyanin and flavonoid contents were measured. Finally, microvinifications were performed and resultant wines subjected to sensory evaluation.Results showed that the use of kaolin increased grapevine intrinsic WUE (+18% on average as compared to unsprayed vines) without affecting berry and bunch weight and quantity, or sugar level. Anthocyanin content increased (+35%) in kaolin treatment, and the wine was judged more attractive (p-value wine was the least appreciated. This study demonstrates that particle film technology can improve vine WUEi and wine quality at the same time, while traditional antitranspirants were not as effective for these purposes. This positive effect can be used in interaction with other already-demonstrated uses of particle film technology, such as pest control and sunburn reduction, in order to achieve more sustainable vineyard management.

  17. Comparing Kaolin and Pinolene to Improve Sustainable Grapevine Production during Drought.

    Directory of Open Access Journals (Sweden)

    Luca Brillante

    Full Text Available Viticulture is widely practiced in dry regions, where the grapevine is greatly exposed to water stress. Optimizing plant water use efficiency (WUE without affecting crop yield, grape and wine quality is crucial to limiting use of water for irrigation and to significantly improving viticulture sustainability. This study examines the use in vineyards of particle film technology (engineered kaolin and compares it to a film-forming antitranspirant (pinolene, traditionally used to limit leaf water loss, and to an untreated control. The trial was carried out under field conditions over three growing seasons, during which moderate to very severe plant water stress (down to -1.9 MPa was measured through stem water potential. Leaf stomatal conductance (gs and photosynthesis rate (An were measured during the seasons and used to compute intrinsic WUE (WUEi, defined as An/gs ratio. Leaf temperature was also recorded and compared between treatments. Bunch quantity, bunch and berry weight, sugar accumulation, anthocyanin and flavonoid contents were measured. Finally, microvinifications were performed and resultant wines subjected to sensory evaluation.Results showed that the use of kaolin increased grapevine intrinsic WUE (+18% on average as compared to unsprayed vines without affecting berry and bunch weight and quantity, or sugar level. Anthocyanin content increased (+35% in kaolin treatment, and the wine was judged more attractive (p-value <0.05 and slightly more appreciated (p-value < 0.1 than control. Pinolene did not increase WUEi, limiting An more than gs; grapes with this treatment contained lower sugar and anthocyanin content than control, and the obtained wine was the least appreciated. This study demonstrates that particle film technology can improve vine WUEi and wine quality at the same time, while traditional antitranspirants were not as effective for these purposes. This positive effect can be used in interaction with other already

  18. Influence of kaolin and firing temperature on the mullite formation in porous mullite-corundum materials

    International Nuclear Information System (INIS)

    Mahnicka, L; Svinka, R; Svinka, V

    2011-01-01

    The refractory ceramics became very important in both the traditional and the advanced materials applications as it has outstanding thermal and mechanical properties. The refractoriness of ceramics can be achieved by getting the mullite-corundum. Refractory ceramics with high porosity serve as a heat insulator and constructional material. Three series of porous mullite-corundum ceramic samples were prepared from Al 2 O 3 (Nabalox, Germany) and pure SiO 2 in 2.57:1 ratio that was conformed to mullite compositions (3Al 2 O 3 ·2SiO 2 ). α-Al 2 O 3 (d 50 = 4 μm) and γ-Al 2 O 3 (d 50 = 80 μm) were in 1:3 ratio. Quantity of kaolin (MEKA, Germany) was 10, 20 and 30 wt.%. Porous materials were prepared by slip casting of suspension of raw materials, where the aluminium paste (0.18 wt.%) was used as a pore former. Water content in the suspensions was 38-40 wt.%. Pore formation occured in result of hydrogen formation in chemical reaction between aluminium paste and water. The samples were sintered at 1650, 1700 and 1750°C temperature for one hour. SiO 2 and γ-Al 2 O 3 on the contrary reduced mechanical properties, but decreased shrinkage. Using of α-, γ-Al 2 O 3 , SiO 2 and kaolin in corresponding ratios the samples with open porosity of 30 to 54 vol% were acquired. The relative amounts of pores depended on the initial content of kaolin and on firing temperature.

  19. Experiment study on the thermal properties of paraffin/kaolin thermal energy storage form-stable phase change materials

    International Nuclear Information System (INIS)

    Lv, Peizhao; Liu, Chenzhen; Rao, Zhonghao

    2016-01-01

    Highlights: • Different particle sizes of kaolin were employed to load paraffin. • The effects and reasons of particle size on thermal conductivity were studied. • Thermal property and thermal stability of the composites were investigated. • The leakage and thermal storage and release rate of the composites were studied. • The effect of vacuum impregnation method on thermal conductivity was investigated. - Abstract: In this paper, different particle sizes of kaolin were employed to incorporate paraffin via vacuum impregnation method. The paraffin/kaolin composites were characterized by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimeter (DSC) and Thermogravimetry (TG). The results showed that the paraffin/kaolin composite with the largest particle size of kaolin (K4) has the highest thermal conductivity (0.413 W/(m K) at 20 °C) among the diverse composites. The latent heat capacity of paraffin/K4 is 119.49 J/g and the phase change temperature is 62.4 °C. In addition, the thermal properties and thermal conductivities of paraffin/K4 with different mass fraction of K4 (0–60%) were investigated. The thermal conductivities of the composites were explained in microcosmic field. The phonon mean free path determines the thermal conductivity, and it can be significantly affected by temperature and the contact surface area. The leaks, thermal storage and release properties of pure paraffin and paraffin/kaolin composites were investigated and the composites presented good thermal stabilities.

  20. Fly ash/Kaolin based geopolymer green concretes and their mechanical properties

    Directory of Open Access Journals (Sweden)

    F.N. Okoye

    2015-12-01

    Full Text Available Geopolymer concrete mixes were cast using fly ash, kaolin, sodium hydroxide, potassium hydroxide, sodium silicate and aggregates. Portland cement concrete (M30 was used as a reference sample. The effect of silica fume, temperature (40 °C, 60 °C, 80 °C, 100 °C and 120 °C, sodium and potassium hydroxides and different superplasticizers on the compressive strength are reported [1]. Maximum strength was found at 100 °C and 14 M alkali solution [1].

  1. Synthesis and characterization of zeolite NaP using kaolin waste as a source of silicon and aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrando, Edemarino Araujo, E-mail: edemarino@ufpa.br [Universidae Federal do Para (UFPA), Maraba, PA (Brazil). Fac. de Engenharia de Materias. Lab. de Materiais Ceramicos; Andrade, Christiano Gianesi Bastos; Valenzuela-Diaz, Francisco Rolando [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Dept. de Metalurgia e Engenharia de Materiais; Rocha Junior, Carlos Augusto Ferreira da; Neves, Roberto de Freitas [Universidae Federal do Para (UFPA), Maraba, PA (Brazil). Int. de Tecnologia. Fac. de Engenharia Quimica; Angelica, Romulo Simoes [Universidae Federal do Para (UFPA), Maraba, PA (Brazil). Inst. de Geociencias. Fac. de Geologia

    2014-08-15

    The synthesis of zeolite NaP using kaolin waste, from the Amazon region, as a predominant source of silicon and aluminum has been studied. The zeolitisation process occurred in hydrothermal conditions using static autoclaving and the effects of time, temperature, and the Si/Al ratio were investigated. The starting material and the phases formed as reaction products were characterized by XRD, SEM and FTIR. The results showed that pure zeolite NaP is hydrothermally synthesized, at 100 °C for 20 hours, using meta kaolin waste material in alkaline medium in presence of additional silica. The XRD and SEM analyses indicate that the synthesized zeolite presents good crystallinity. (author)

  2. Synthesis and characterization of zeolite NaP using kaolin waste as a source of silicon and aluminum

    International Nuclear Information System (INIS)

    Hildebrando, Edemarino Araujo; Andrade, Christiano Gianesi Bastos; Valenzuela-Diaz, Francisco Rolando; Rocha Junior, Carlos Augusto Ferreira da; Neves, Roberto de Freitas; Angelica, Romulo Simoes

    2014-01-01

    The synthesis of zeolite NaP using kaolin waste, from the Amazon region, as a predominant source of silicon and aluminum has been studied. The zeolitisation process occurred in hydrothermal conditions using static autoclaving and the effects of time, temperature, and the Si/Al ratio were investigated. The starting material and the phases formed as reaction products were characterized by XRD, SEM and FTIR. The results showed that pure zeolite NaP is hydrothermally synthesized, at 100 °C for 20 hours, using meta kaolin waste material in alkaline medium in presence of additional silica. The XRD and SEM analyses indicate that the synthesized zeolite presents good crystallinity. (author)

  3. Characterization of kaolin and granite waste for formulation of porcelain stoneware tiles

    International Nuclear Information System (INIS)

    Luna da Silveira, G.C.; Acchar, W.; Gomes, U.U.; Silva, B.K.O.; Luna da Silveira, R.V.; Labrincha, J.A.; Costa, M.C.P.

    2016-01-01

    To produce a stoneware tiles is necessary develop a formulation that satisfies their structural characteristics, micro-structural, physical and mechanical properties. Thus, in order to create a formulation for porcelain stoneware tiles that give use to kaolin and granite waste used in the production of ceramic materials were asked the following characterizations: chemical analysis, mineralogical, thermal and particle size. We found that in the kaolin sample it presents a rate of silicon oxide and aluminum oxide similar to those found in the work of other investigators, about 45.23% SiO2 and 37.39% Al_2O_3. In the granite waste, the percentage of silicon oxide and aluminum oxide are also similar to those observed in other studies, with about 74.89% SiO2 and 10.54% Al_2O_3. Both the percentage of SiO_2 and Al_2O_3 founded in these two samples satisfy the percentage required in the manufacturing of porcelain stoneware tiles. (author)

  4. Synthesis and characterization of kaolin assisted metal nanocomposite and its tremendous adsorptive and photo catalytic applications

    International Nuclear Information System (INIS)

    Tahir, H.; Saad, M.; Saleem, U.

    2018-01-01

    The present work demonstrates the synthesis of Kaolin assisted Ag nanocomposite (Ag-KNC) by co-precipitation method. The surface morphology of them was studied through SEM and chemical constituents by EDS techniques. The removal of efficaciousness of Ag-KNC was tested by Malachite Green Oxalate (MGO) dye through batch adsorption and photocatalytic strategies. The sorption experiments were preceded under the optimized conditions like amount of adsorbent, stay time and pH. The feasibility of the process was determined by employing Freundlich, Langmuir and D-R (Dubinin –Radushkevich) adsorption isotherms. The pH at point of zero charge (pHpzc) was conjointly calculable to work out the surface neutrality of the system. The salt effect for the removal of MGO dye was investigated. Thermodynamic parameters like free energy (∆Go), entropy (∆So) and enthalpy (∆Ho), of the system was investigated. Adsorption Kinetic was resolute by Intra particle diffusion (IPD) and Boyd’s models. An attempt was made to prepare (Ag-KCN) nanophoto catalyst by UV light assisted degradation of Malachite Green Oxalate (MGO) dye. They were prepared by the reduction of Ag+ ion under alkaline conditions on kaolin surface. The photo degradation (PD) process was initiated by photo generated electrons. The present study recommended that projected strategies were successfully applied for the remediation of environmental problems. (author)

  5. Electrokinetic remediation of heavy metals contaminated kaolin by a CNT-covered polyethylene terephthalate yarn cathode

    International Nuclear Information System (INIS)

    Yuan, Lizhu; Li, Haiyan; Xu, Xingjian; Zhang, Jing; Wang, Nana; Yu, Hongwen

    2016-01-01

    In the current study, carbon nanotube (CNT) covered polyethylene terephthalate yarns (PET-CNT) electrode has been investigated as a novel cathode material for the electrokinetic (EK) remediation of multi-metals (Cd, Cu, Ni, Pb, Zn) contaminated kaolin. The results of scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) showed that CNT was successfully covered on the surface of PET. The results obtained from EK process showed that PET-CNT as a cathode obviously elevated electric current and electro-osmotic flow (EOF), significantly decreased kaolin pH, and enhanced heavy metals removal efficiencies. The removal efficiencies of Cd, Cu, Ni, Pb, and Zn in PET-CNT treatment were 89.7%, 63.6%, 90.7%, 19.2%, and 88.7%, respectively. In comparison with the Pt/Ti and graphite treatments, the removal efficiencies of Cd, Ni, and Zn were improved at least about 30%, Cu and Pb were improved at least 16.6% and 6.9%, respectively. Our results demonstrated the PET-CNT was a good alternative cathode material for enhancing efficiency of EK remediation.

  6. Potential of kaolin-based particle film barriers for Formosan subterranean termite (Isoptera: Rhinotermitidae) control

    Science.gov (United States)

    Wiltz, B.A.; Woodson, W.D.; Puterka, G.J.

    2010-01-01

    Effects of three particle film products on Formosan subterranean termites, Coptotermes formosanus Shiraki, were evaluated in feeding, tunneling, and contact assays. The particle films, hydrophobic M96-018 and hydrophilic Surround and Surround WP are based on the inert clay mineral kaolin. In 2-week long no-choice feeding tests, significant mortality occurred only with M96-018-coated wood. When a choice was provided, M96-018 and Surround were consumed at higher rates than untreated wood. Surround WP did not differ from controls in either test. In the tunneling assay termites were given the option of crossing a kaolin-sand mixture to reach an alternate food source. After 3-weeks, rates of 1% and 5% M96-018 provided an effective barrier to Formosan termite tunneling, while termites were not stopped by rates as high as 20% Surround and Surround WP. Dust treatments of all three formulations caused significant increases in mortality within 24 h, with mortality rates ranging from 72.0 - 97.3% within 72 h of treatment. The particle films were most effective when moisture levels were low, suggesting that desiccation was the mechanism for mortality. All particle films showed potential for use in above ground applications while hydrophobic M06-018 has the most potential as a soil barrier to subterranean termites.

  7. Effect of Rice Husk and Diatomite on the Insulating Properties of Kaolin - Clay Firebricks

    Directory of Open Access Journals (Sweden)

    Emmanuel Ogo ONCHE

    2007-09-01

    Full Text Available This work was carried out to investigate the effect of rice husk and diatomite on the insulating properties of kaolin-clay firebrick. Five firebrick samples of different compositions were fired at 900°C, 1000°C, 1100°C, and 1200°C. Samples A-E are all insulating firebricks that can withstand temperatures ranging from 900°C to 1200°C since none of the samples crumbled during firing. The results showed that they all had good insulating characteristics with their highly porous structure making them suitable for backup insulation. Mixing ratios of 3:2:4:1 representing weight in grams of kaolin, plastic clay, rice husk and diatomite respectively for sample D gave the optimum performance values in terms of modulus of rupture, apparent porosity, apparent density, bulk density, and thermal conductivity at all temperatures. At 1200°C, the values are 22.57kgf/cm2 for modulus of rupture, 98.25% for apparent porosity, 2.38g/cm3 for apparent density, 1.11g/cm3 for bulk density, and 0.038w/mK for thermal conductivity.

  8. Synthesis and characterization of mangan oxide coated sand from Capkala kaolin

    Science.gov (United States)

    Destiarti, Lia; Wahyuni, Nelly; Prawatya, Yopa Eka; Sasri, Risya

    2017-03-01

    Synthesis and characterization of mangan oxide coated sand from quartz sand fraction of Capkala kaolin has been conducted. There were two methods on synthesis of Mangan Oxide Coated Sand (MOCS) from Capkala Kaolin compared in this research. Characterization of MOCS was done by using Scanning Electron Microscope/Energy Dispersive X-Ray Spectrometer (SEM/EDX) and X-Ray Diffraction (XRD). The MOCS was tested to reduce phosphate in laundry waste. The result showed that the natural sand had bigger agregates and a relatively uniform structural orientation while both MOCS had heterogen structural orientation and manganese oxide formed in cluster. Manganese in first and second methods were 1,93% and 2,63%, respectively. The XRD spectrum showed clear reflections at 22,80°, 36,04°, 37,60° and a broad band at 26,62° (SiO2). Based on XRD spectrum, it can be concluded that mineral constituents of MOCS was verified corresponding to pyrolusite (MnO2). The former MOCS could reduce almost 60% while the later could reduce 70% phosphate in laundry waste.

  9. Attenuation measurements of ultrasound in a kaolin-water slurry. A linear dependence upon frequency

    International Nuclear Information System (INIS)

    Greenwood, M.S.; Mai, J.L.; Good, M.S.

    1993-01-01

    The attenuation of ultrasound through a kaolin-water slurry was measured for frequencies ranging from 0.5 to 3.0 MHz. The maximum concentration of the slurry was for a weight percentage of 44% (or a volume fraction of 0.24). The goal of these measurements was to assess the feasibility of using ultrasonic attenuation to determine the concentration of a slurry of known composition. The measurements were obtained by consecutively adding kaolin to the slurry and measuring the attenuation at each concentration. After reaching a maximum concentration a dilution technique was used, in which an amount of slurry was removed and water was added, to obtain the attenuation as a function of the concentration. The dilution technique was the more effective method to obtain calibration data. These measurements were carried out using two transducers, having a center frequency of 2.25 MHz, separated by 0.1016m (4.0 in.). The maximum attenuation measured in these experiments was about 100Np/m, but the experimental apparatus has the capability of measuring a larger attenuation if the distance between the two transducers is decreased. For a given frequency, the data show that ln V/V 0 depends linearly upon the volume fraction (V is the received voltage for the slurry and V 0 is that obtained for water). This indicated that each particle acts independently in attenuating ultrasound. 12 refs., 7 figs., 3 tabs

  10. Recovery of kaolinite from tailings of Zonouz kaolin-washing plant by flotation-flocculation method

    Directory of Open Access Journals (Sweden)

    Kianoush Barani

    2018-04-01

    Full Text Available The traditional processing of kaolin is achieved by dispersion of the mined ore and classification by multistage hydrocyclone plants. The inefficiencies inherent to cyclones produce a middling product that is commonly disposed back into the quarry. In this research, recovery of kaolinite from tailings of Zonouz kaolin washing plant, which is located in Iran was investigated by flotation and flotation- flocculation. Flotation experiments show that the flotation of kaolinite from the tailings is better in an acidic than in an alkaline medium containing cationic collectors. Flotation under acidic condition causes problems such as equipment corrosion at industrial scale. As a result, the cationic flotation of kaolinite is enhanced by addition of polyacrylamide as a flocculant. The results showed flocculation by polyacrylamide improved flotation of kaolinite within a range of pH. With 300 g/t dodecylamine, 500 g/t aluminum chloride, 50 g/t pine oil (frother, 15 g/t polyacrylamide, at pH = 7 and without de-slimming a product has 37.19% Al2O3, 54.19% SiO2 and 34.43% mass recovery was archived. Keywords: Kaolinite, Flotation, Flocculation, Cetylpyridinium chloride, Dodecylamine, Aluminum chloride, Polyacrylamide

  11. Study of the effect of Kaolin in the mortar of cement matrices by confinement of ion exchange resins

    Directory of Open Access Journals (Sweden)

    Labied S.

    2018-01-01

    Full Text Available Radioactive waste arising as a result of nuclear activities should be safely managed from its generation to final disposal in an appropriate conditioned form to reduce the risk of radiation exposure of technical personnel and of the public and to limit contamination of the environment. The immobilization of low and intermediate level radioactive wastes in cementitious matrices is the most commonly used technique to produce inexpensive waste matrix that complies with regulatory requirements in order to protect humans and the environment against nuisance caused by ionizing radiation. Cement based materials are used in radioactive waste management to produce stable waste forms. This matrix constitutes the first build engineering barrier in disposal facilities. In this work, the kaolin is used to enhance the mechanical performance of the matrix of confinement of ion exchange resins by gradually replacing the sand in mortar with kaolin clay. The Kaolin clay sample was a special pure product, sourced from a foreign country. The maximum quantity of resins that can be incorporated into the mortar formulation without the packages losing their strength is 13.915% which results in a better mechanical strength at 6.7686 MPA compression with kaolin.

  12. Adsorpce toxických oxoaniontů Se na povrchově upravený kaolin

    Czech Academy of Sciences Publication Activity Database

    Herzogová, L.; Doušová, B.; Lhotka, M.; Machovič, Vladimír; Schweigstillová, Jana; Koloušek, D.

    2012-01-01

    Roč. 106, č. 8 (2012), s. 759-764 ISSN 0009-2770 Institutional research plan: CEZ:AV0Z30460519 Keywords : adsorption * oxoanions Se * surface-modified kaolins Subject RIV: CA - Inorganic Chemistry Impact factor: 0.453, year: 2012 http://www.chemicke-listy.cz/docs/full/2012_08_759-764.pdf

  13. Characterization of silica polymorphs in kaolins by X-ray diffraction before and after phosphoric acid digestion and thermal treatment

    International Nuclear Information System (INIS)

    Kahraman, Sibel; Oenal, Mueserref; Sarikaya, Yueksel; Bozdogan, Ihsan

    2005-01-01

    To characterize silica polymorphs (silicas) in some kaolins, orthophosphoric acid digestion (240 deg. C, 15 min), and thermal treatment (1050 deg. C, 24 h) were applied to eight samples. The original, digested, and heated samples were examined by X-ray diffraction (XRD). Crystalline silica quartz (SiO 2 ) was identified from the standard XRD patterns of the original kaolins; all contained quartz. On the other hand, hydrated partially crystalline silicas (SiO 2 .nH 2 O), such as well-ordered opal-C and opal-CT, were not readily distinguished from high-temperature crystalline silica, α-cristobalite, using standard XRD patterns of the original kaolins because, sharp and intense characteristic XRD peaks (h k l = 1 0 1) centered near 0.4 nm for opal-C, opal-CT, and α-cristobalite coincided. In order to distinguish these silicas the XRD patterns of the digested and heated samples were evaluated. It was observed that the 1 0 1 peaks disappear and sharpen in the course of digestion and heating, respectively. Because, the crystallinity of α-cristobalite does not change by these treatments, it was concluded that the kaolins contain opal-C and opal-CT or their mixtures in amorphous opal-A (SiO 2 .nH 2 O), but not α-cristobalite, which is probably human carcinogen. Because, the crystallinity increases in order opal-CT and opal-C, the narrowing in width at half-maximum peak height (FWHM) 1 0 1 must be more for opal-CT than opal-C by heating. Therefore, to distinguish opal-CT and opal-C from each other, the FWHM values before and after the heating process, were examined. Based on the results, it was estimated that six kaolins contain opal-CT in opal-A matrix, one kaolin contains only opal-A in a trace amount, and one kaolin contains non-opals

  14. Synthesis of microporous material faujasite-type from kaolin waste; Sintese de material microporoso do tipo faujasita a partir de rejeito de caulim

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrando, E.A.; Valenzuela-Diaz, F.R., E-mail: edemarino@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Dept. de Engenharia Metalurgica e de Materiais. Lab. de Materias-Primas Particuladas e Solidos nao Metalicos; Angelica, R.S. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Geociencias. Fac. de Geologia; Neves, R.F. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Tecnologia. Fac. de Engenharia Quimica

    2010-07-01

    Zeolite with structure faujasite was synthesized using kaolin waste from kaolin processing industries for paper coating as predominant source of silicon and aluminum; the starting material was characterized by XRF, XRD, DTA/TG, SEM, and products obtained by XRD and SEM. Synthesis in hydrothermal conditions occurred on autoclave and time-temperature effects, as well as the relationship Si/Al were considered. The results show that the methodology developed with the waste of calcined kaolin reacting at 90 deg C for 20 hours in an alkaline medium, in the presence of an additional source of silica was obtained zeolite Y as single phase present in the product. (author)

  15. Alternatif Pembuatan Biodiesel Melalui Transesterifikasi Minyak Castor (Ricinus communis Menggunakan Katalis Campuran Cangkang Telur Ayam dan Kaolin

    Directory of Open Access Journals (Sweden)

    Soni - Setiadji

    2017-05-01

    Full Text Available Biodiesel was produced by transesterification of castor oil (Ricinus communis using a catalyst of CaO and kaolin (CaO / kaolin had been performed. CaO was obtained from the calcination of eggshell. Castor oil is selected as biodiesel feedstock because it belongs to non-food oil and easy to cultivate. In general, the research method aims to comprise the CaO / Kaolin catalysts with a ratio of 15 mmol CaO per 1 gram of kaolin activated using impregnation method and biodiesel produced through transesterification of castor oil using the catalyst at 65 ºC for 8 hours with ratio of castor oil: methanol: catalyst (1: 15: 5% w / w. The reaction is carried out on the reflux system. The XRD analysis show the presence of silica and potassium aluminum silicate hydroxide in the catalyst. The EDS results show the catalyst-forming components CaO and silica. The FTIR analysis results show the absorption peak in the functional group forming the methyl ester compound. Based on the characterization of GC-MS, the largest methyl ester components contained in biodiesel are methyl risinoleate, methyl elaidat, methyl stearate, methyl linoleate, and methyl palmitate. The overall conversion of castor oil to methyl ester using CaO / kaolin catalyst is 97.36%. The largest component in castor oil is risinoleic acid, has been successfully converted to methyl risinoleate by 74.75%.DOI: http://dx.doi.org/10.15408/jkv.v0i0.4778

  16. Effects of Melatonin on the Cerebellum of Infant Rat Following Kaolin-Induced Hydrocephalus: a Histochemical and Immunohistochemical Study.

    Science.gov (United States)

    Uyanıkgil, Yiğit; Turgut, Mehmet; Baka, Meral

    2017-02-01

    Hydrocephalus is a developmental disorder causing abnormally collected cerebrospinal fluid within the cerebral ventricles. It leads to bigger skulls and many dysfunctions related to the nervous system. Here, we addressed whether exogenous melatonin administration could reverse the clinical features of kaolin-induced hydrocephalus in infantile rats. A controlled double-blinded study was conducted in 2-week-old 45 Wistar albino rats, which were divided into three groups: Group A, the control group, received intracisternal sham injection with solely the needle insertion; group B, the hydrocephalus group, was treated with isotonic NaCl after kaolin injection; and group C, the hydrocephalus + melatonin group, was given i.p. exogenous melatonin at a dose of 0.5 mg/100 g body weight after kaolin injection. Histological and immunohistochemical analyses were performed after the induction of hydrocephalus and melatonin administration. Glial fibrillary acidic protein was stained by immunohistochemical method. TUNEL method was used to define and quantitate apoptosis in the cerebellar tissues. Statistical analysis was performed by nonparametric Kruskal-Wallis H test, and once significance was determined among means, post hoc pairwise comparisons were carried out using Mann-Whitney U test. We found that melatonin administration significantly ameliorated ratio of substantia grisea area/substantia alba area in the cerebellum of infantile rats. Histologically, there was a significant reduction in the number of cerebellar apoptotic cells after the hydrocephalus induced by kaolin (P cerebellum were reversed by systemic melatonin administration in infantile rats with kaolin-induced hydrocephalus. Nevertheless, further studies are needed to suggest melatonin as a candidate protective drug in children with hydrocephalus.

  17. Analysis of influence of the inclusion of residue of kaolin on the properties and on the variation of major oxides present in clay city Bento Fernandes (RN)

    International Nuclear Information System (INIS)

    Silva, Hugo Fernandes Medeiros de; Lima, Cassiano dos Santos; Silva, Gilson Garcia da; Machado, Tercio Graciano; Albuquerque, Rosanne Azevedo de; Gomes, Uilame Umbelino

    2011-01-01

    Research Foundation for Support of Education and Technological Development of Rio Grande do Norte - FUNCERN found that 38% of deposits visited in RN products sold in other states, 20% did not sell tiles RN, 8% preferred the tiles outside. All to supply a market segment demanding and are looking for differentiated products, which require manufacturers of certified quality products contributing to the quality process in the construction industry. It is known that the ceramic bodies are manufactured from the composition of two or more materials with different characteristics in their composition. Thus, one of the key steps is the dosage of raw materials and additives. This device allows to target the many wastes from industry. This paper aims to study the physical and mechanical properties of ceramic body resulting from the inclusion of residual kaolin clay on the city of Bento Fernandes (RN), analyzing the influence of variation of major oxides present in the raw material on the behavior of the final product. (author)

  18. Unbelievable but true: Partial thromboplastin time, kaolin 120 s and yet no surgical bleed!

    Directory of Open Access Journals (Sweden)

    Shagun Bhatia Shah

    2017-01-01

    Full Text Available Partial thromboplastin time, kaolin (PTTK is a global test sensitive to low levels of all the coagulation factors, except Factor VII and Factor XIII. Patients with extensive cancer have a propensity to develop a shortened PTTK. Our breast cancer patient had a prolonged PTTK result roughly 4 times the normal values. A detailed description of the preoperative workup including the special investigations is required to ascertain the cause of the prolongation and precautions taken, leading to successful breast cancer surgery and postoperative period in this patient follows. Allowing the surgeon to operate a patient with a PTTK >120 s and simultaneously at risk of thrombosis due to lupus anticoagulant is possible with a calculated risk and thorough preoperative evaluation. Prophylactic fresh frozen plasma and deep venous thrombosis prophylaxis have an important role.

  19. Kinetic study of formation of sodalite from a kaolin waste of Jari river - PA, Brazil

    International Nuclear Information System (INIS)

    Silva, L.N. da; Paz, S.P.A. da; Angelica, R.S.; Neves, R.F.

    2011-01-01

    Zeolites are materials with a wide industrial application, which has motivated the development of a large number of scientific papers on this topic. This work presents a kinetic study of the formation process of sodalite produced from the reaction of the kaolin waste in the presence of sodium hydroxide solution (5M) performed at temperatures of 80, 100, 120 and 150 ° C. The process was conducted in batch, static, and autoclaves lined with Teflon, and monitoring the kinetics was performed by ex situ XRD analysis of the materials obtained in the time interval from 2 to 24 hours. The kinetic model that best describes this transformation is zero-order homogeneous reaction. Finally, we conclude that the technique of X-ray diffraction is a powerful tool to study the kinetics of phase transformation ex situ. (author)

  20. For production of ceramic plates coating using waste kaolin, granite and marble

    International Nuclear Information System (INIS)

    Sales, J.L.; Morais, C.R.S.; Lima, L.M.R.; Altidis, M.E.D.

    2011-01-01

    The objective is to benefit and characterize waste from kaolin, marble and granite studying their thermal properties and spectroscopic in employment perspective on ceramic production of flooring boards. The residues were benefited through the process of dry grinding mill in greyhounds and passed through sieve 0.074 mm (ABNT No. 200), observing their suitability for the formulation of ceramic pastes. Tests were performed physicochemical characterization (particle size analysis, X-ray fluorescence and X-ray diffraction) and thermal (differential thermal analysis and thermogravimetry). The results showed that these residues showed satisfactory properties for the purpose for which it proposes, and contribute to reducing environmental impacts, allowing the reuse of the production of ceramic plates (author)

  1. Color and shade parameters of ultramarine zeolitic pigments synthesized from kaolin waste

    International Nuclear Information System (INIS)

    Menezes, Raquel Aranha de; Paz, Simone Patricia Aranha da; Angelica, Romulo Simoes; Neves, Roberto de Freitas; Pergher, Sibele Berenice Castella

    2014-01-01

    Ultramarine pigments were successful synthesized from zeolite A obtained from kaolin waste. This waste has been used as an excellent source of silicon and aluminum for zeolite synthesis because of its high kaolinite concentrations and low contents of other accessory minerals. The cost is naturally less than the industrialized product. Color additives (Sulfur and Sodium Carbonate) were mixed with different proportions of zeolite A and further calcined for 5 h at 500 °C. They were characterized by XRD and XRF in addition to visual classification by color and shade. These products show colors from blue to green at different shades, both influenced by the amount of additives and cooling rate after calcination. Thus, a different quantity of the same additives in the same zeolitic matrix provides an increase in the color intensity. Cooling rate after calcination induces the color change which is substantially important in the pigments production. (author)

  2. Color and shade parameters of ultramarine zeolitic pigments synthesized from kaolin waste

    Energy Technology Data Exchange (ETDEWEB)

    Menezes, Raquel Aranha de; Paz, Simone Patricia Aranha da; Angelica, Romulo Simoes; Neves, Roberto de Freitas; Pergher, Sibele Berenice Castella, E-mail: raquel_arn@hotmail.com [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Geociencias. Grupo de Mineralogia e Geoquimica Aplicada

    2014-08-15

    Ultramarine pigments were successful synthesized from zeolite A obtained from kaolin waste. This waste has been used as an excellent source of silicon and aluminum for zeolite synthesis because of its high kaolinite concentrations and low contents of other accessory minerals. The cost is naturally less than the industrialized product. Color additives (Sulfur and Sodium Carbonate) were mixed with different proportions of zeolite A and further calcined for 5 h at 500 °C. They were characterized by XRD and XRF in addition to visual classification by color and shade. These products show colors from blue to green at different shades, both influenced by the amount of additives and cooling rate after calcination. Thus, a different quantity of the same additives in the same zeolitic matrix provides an increase in the color intensity. Cooling rate after calcination induces the color change which is substantially important in the pigments production. (author)

  3. Waste characterization emanated from kaolin submitted the improvement to process hydrocycloning

    International Nuclear Information System (INIS)

    Barbosa Neto, M.C.; Nunes, A.S.; Caetano, A.L.A.; Marques, V.C.; Macedo, D.A.; Ferreira, H.S.; Dutra, R.P.S.

    2016-01-01

    The hydrocyclones are equipment commonly used for separation of particles by size. The resulting material of this process usually presents different characteristics of the material, which was not subjected to treatment. Therefore, a study of the waste characteristics derived from kaolin processing submitted to hydrocycloning process compared to the same residue without going through the process was executed. The different samples were characterized by X-ray diffraction, X-ray fluorescence, particle size analysis and thermal analysis. The results indicate that the hydrocycloning not modify the mineralogical structure nor chemical material. The particle size analysis identified that the fine fraction, resulting from the process, presented particle size lower than the reference material. (author)

  4. Mineralizer effects on mullite formation from kaolin processing wastes in Para-Brazil

    International Nuclear Information System (INIS)

    Martelli, Marlice Cruz; Angelica, Romulo Simoes; Neves, Roberto de Freitas

    2009-01-01

    Mullite is a relatively rare mineral in nature, formed under exceptional conditions of high temperature and pressure, which can be used to synthesize this mineral. Mullite presents good chemical and thermal stability among others properties that explain the importance of mullite in traditional and advanced ceramics. This research proposes the development of a process to synthesize mullite using the wastes from kaolin processing industries located in the Rio Jari (Monte Dourado-PA) and Rio Capim (Ipixuna-PA) districts. The synthesized materials will be studied for application as silicon-aluminum refractory bricks. The steps are mineralogical and chemical characterization, verifying the differences between the materials processing through firing of the wastes at increasing levels of temperature with 100 deg C increments, ranging from 600 to 1000 deg C and 1200 to 1500 deg C, during 3 hours at each level. Methods include the study of temperature and impurities effects through X-ray-powder and scanning electron microscopy. (author)

  5. Incorporation of waste and fiber kaolin caroa panels in Medium Density Fiberboard - MDF

    International Nuclear Information System (INIS)

    Bezerra, A.F.C.; Santana, L.N.L.; Neves, G.A.; Carvalho, L.H. de; Lopes, F.F.M.

    2012-01-01

    Medium-density panels are composites molded under high temperature and pressure which have physical and mechanical properties similar to those of solid wood. Their composition includes eucalyptus grandis fibers and pinus elliotii fibers, but other fibers can be used such as caroa fibers. The goal of this work was to manufacture panels which kaolin waste and caroa fibers and compare their physical, chemical and mechanical of these panels with a others. Both residue and the fibers were characterized by: differential thermal analysis, thermal gravimetric analysis and Xray diffraction. Through the process of pressing the test specimens were fabricated, test samples were evaluated by three point bending, internal bond, water absorption and swelling in thickness. The samples have low levels of thickness swelling, flexural strength and higher tensile and absorption content relative to commercial MDF. (author)

  6. Multiple scattering wavelength dependent backscattering of kaolin dust in the IR: Measurements and theory

    Science.gov (United States)

    Ben-David, Avishai

    1992-01-01

    Knowing the optical properties of aerosol dust is important for designing electro-optical systems and for modeling the effect on propagation of light in the atmosphere. As CO2 lidar technology becomes more advanced and is used for multiwavelength measurements, information on the wavelength dependent backscattering of aerosol dust particles is required. The volume backscattering coefficient of aerosols in the IR is relatively small. Thus, only a few field measurements of backscattering, usually at only a few wavelengths, are reported in the literature. We present spectral field measurements of backscattering of kaolin dust in the 9-11 micron wavelength range. As the quantity of dust increases, multiple scattering contributes more to the measured backscattered signal. The measurements show the effect of the dust quantity of the spectral backscatter measurements. A simple analytical two stream radiative transfer model is applied to confirm the measurements and to give insight to the multiple scattering spectra of backscattering.

  7. Production of zeolite A come from rio Capim Kaolin: Study on recycle of sodium hydroxide solution

    International Nuclear Information System (INIS)

    Moraes, C.G.; Rodrigues, E.C.; Rocha Junior, C.A.F.; Macedo, E.N.; Neves, R.F.

    2011-01-01

    The kaolin processing industry is an important economic sector in the State of Para, but produces huge amounts of wastes composed essentially of kaolinite. The production processes of zeolites typically use sodium hydroxide in excess, are discarded. So the objective is the development process for production of zeolite A which allows the reuse of the solution of sodium hydroxide used in excess through your recycling. Presents the results of XRD, SEM of the zeolites produced in five consecutive cycles performed at a temperature of 110°C/24h as a source of sodium hydroxide solution of sodium 5 M, using a molar ratio of Si/Al = 1 and Na/Al = 1,26. (author)

  8. Sintering of anorthite based ceramics prepared from kaolin DD2 and calcite

    Energy Technology Data Exchange (ETDEWEB)

    Zaiou, S.; Harabi, A.; Harabi, E.; Guechi, A.; Karboua, N.; Benhassine, M.-T.; Zouai, S.; Guerfa, F., E-mail: Zaiou_21@yahoo.fr, E-mail: harabi52@gmail.com, E-mail: semouni84@gmail.com, E-mail: guechia@yahoo.fr, E-mail: kanour17@yahoo.fr, E-mail: mtb25dz@gmail.com, E-mail: zouaisouheila@yahoo.fr, E-mail: guerfatiha@gmail.com [Ceramics Lab., Faculty of Exact Science, Physics Department, Mentouri University of Constantine (Algeria)

    2016-10-15

    In this work, the preparation of anorthite based ceramics using a modified milling system and 80 wt% kaolin (DD2 type) and 20 wt% calcium oxide extracted from CaCO{sub 3} is shown. The choice of these raw materials was dictated by their natural abundance. Previous studies have shown that a simple and vibratory multidirectional milling system using a bimodal distribution of highly resistant ceramics can be successfully used for obtaining fine powders. The prepared samples were sintered at different temperatures ranging between 800 and 1100 °C. It has been found that the relative density of samples sintered at 900 °C for 1 h with a heating rate of 5 °C/min was about 96% of the theoretical density of anorthite (2.75 g/cm{sup 3} ). Finally, the prepared samples were also characterized by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. (author)

  9. Sintering of anorthite based ceramics prepared from kaolin DD2 and calcite

    Directory of Open Access Journals (Sweden)

    S. Zaiou

    Full Text Available Abstract In this work, the preparation of anorthite based ceramics using a modified milling system and 80 wt% kaolin (DD2 type and 20 wt% calcium oxide extracted from CaCO3 is shown. The choice of these raw materials was dictated by their natural abundance. Previous studies have shown that a simple and vibratory multidirectional milling system using a bimodal distribution of highly resistant ceramics can be successfully used for obtaining fine powders. The prepared samples were sintered at different temperatures ranging between 800 and 1100 °C. It has been found that the relative density of samples sintered at 900 °C for 1 h with a heating rate of 5 °C/min was about 96% of the theoretical density of anorthite (2.75 g/cm3. Finally, the prepared samples were also characterized by scanning electron microscopy, X-ray diffraction and Raman spectroscopy.

  10. Sintering of anorthite based ceramics prepared from kaolin DD2 and calcite

    International Nuclear Information System (INIS)

    Zaiou, S.; Harabi, A.; Harabi, E.; Guechi, A.; Karboua, N.; Benhassine, M.-T.; Zouai, S.; Guerfa, F.

    2016-01-01

    In this work, the preparation of anorthite based ceramics using a modified milling system and 80 wt% kaolin (DD2 type) and 20 wt% calcium oxide extracted from CaCO 3 is shown. The choice of these raw materials was dictated by their natural abundance. Previous studies have shown that a simple and vibratory multidirectional milling system using a bimodal distribution of highly resistant ceramics can be successfully used for obtaining fine powders. The prepared samples were sintered at different temperatures ranging between 800 and 1100 °C. It has been found that the relative density of samples sintered at 900 °C for 1 h with a heating rate of 5 °C/min was about 96% of the theoretical density of anorthite (2.75 g/cm 3 ). Finally, the prepared samples were also characterized by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. (author)

  11. Mineralogical and chemical characterization of DD3 kaolin from the east of Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Senoussi, H.; Osmani, H.; Courtois, C.; Bourahli, M. H.

    2016-08-01

    The mineralogical and chemical characteristics, based on X-ray diffraction (XRD) and scanning electron microscopy, of a kaolin known as DD3, from eastern Algeria were examined in the present study. The results showed that kaolin DD3 has an alumina content of 39%. The SiO{sub 2}/Al{sub 2}O{sub 3} molar ratio of 2.14 is close to that of a pure halloysite. The hematite concentration is relatively large and the flux oxides ratios remain as acceptable impurities. Microscopic observations showed a predominant tubular halloysite phase, flattened hexagonal platelets corresponding to the presence of kaolinite and its polymorphs (nacrite, dickite), and hydrated alumina. The SiO{sub 2}/Al{sub 2}O{sub 3} molar ratio and tubular DD3 suggest possible uses in technical ceramics and nano technology applications. Analysis by XRD revealed the presence of many phases. Thermal treatment at 450 degree centigrade and chemical treatment with HCl confirmed the presence of halloysite. The inclusion in the clay of organic molecules (dimethylsulfoxide (DMSO), DMF, and diluted glycerol) showed that the DMSO led to expansion of the inter-planar distance. The intercalation by DMSO molecules resulted in a shift of the basal peak from 10 to 11.02 A and partial displacement of the peak from 3.35 to 3.65 A. These two peaks are characteristic of halloysite. The presence of residual nacrite was also confirmed by the shift of the peak observed at 3.35 A. A full analysis of the XRD patterns using the Match software, based on these results, showed that the DD3 clay consists of >60% halloysite. (Author)

  12. Mineralogical and chemical characterization of DD3 kaolin from the east of Algeria

    International Nuclear Information System (INIS)

    Senoussi, H.; Osmani, H.; Courtois, C.; Bourahli, M. H.

    2016-01-01

    The mineralogical and chemical characteristics, based on X-ray diffraction (XRD) and scanning electron microscopy, of a kaolin known as DD3, from eastern Algeria were examined in the present study. The results showed that kaolin DD3 has an alumina content of 39%. The SiO 2 /Al 2 O 3 molar ratio of 2.14 is close to that of a pure halloysite. The hematite concentration is relatively large and the flux oxides ratios remain as acceptable impurities. Microscopic observations showed a predominant tubular halloysite phase, flattened hexagonal platelets corresponding to the presence of kaolinite and its polymorphs (nacrite, dickite), and hydrated alumina. The SiO 2 /Al 2 O 3 molar ratio and tubular DD3 suggest possible uses in technical ceramics and nano technology applications. Analysis by XRD revealed the presence of many phases. Thermal treatment at 450 degree centigrade and chemical treatment with HCl confirmed the presence of halloysite. The inclusion in the clay of organic molecules (dimethylsulfoxide (DMSO), DMF, and diluted glycerol) showed that the DMSO led to expansion of the inter-planar distance. The intercalation by DMSO molecules resulted in a shift of the basal peak from 10 to 11.02 A and partial displacement of the peak from 3.35 to 3.65 A. These two peaks are characteristic of halloysite. The presence of residual nacrite was also confirmed by the shift of the peak observed at 3.35 A. A full analysis of the XRD patterns using the Match software, based on these results, showed that the DD3 clay consists of >60% halloysite. (Author)

  13. Interpretation of the stiffness and permeability of Sand-Kaolin mixtures in the framework of homogenization

    Directory of Open Access Journals (Sweden)

    Claude Boutin

    2010-03-01

    Full Text Available This study deals with the behaviour of mixtures of sand and saturated kaolin paste considered as composite materials made of permeable and deformable (with non-linear behaviour matrix (the kaolin paste with rigid and impervious inclusions (the sand grains. Oedometric and permeability tests conducted on such mixtures highlight the key role of the state of the clay paste, and show the existence of a threshold of sand grain concentration above which a structuring effect influences both modulus and permeability. At the light of these experiments, the usual and tangent homogenization process (with simplifying assumptions to make the problem manageable has been applied to estimate the mixture permeability and tangent compressibility. Qualitative and quantitative comparisons with experimental data point out the domain of interest and the limitations of such approaches.O estudo lida com o comportamento de misturas compostas por areia e uma pasta de caulinita considerada um material composto feito de uma matriz (caulinita permeável e deformável (com comportamento não-linear com inclusões rígidas e impermeáveis (grãos de areia. Testes de permeabilidade e odométricos conduzidos nestas misturas enfatizam o papel chave de estado da pasta argilosa e mostram a existência de uma concentração crítica de grãos de areia com efeito estruturante que influencia o módulo e a permeabilidade. Sob a luz destes experimentos o processo de homogeneização usual e tangente (com hipóteses simplificadoras para tornar o problema tratável foi aplicado para estimar a permeabilidade da mistura e a compressibilidade tangente. Comparações qualitativas e quantitativas com dados experimentais apontam o domínio de interesse bem como a limitação destas abordagens.

  14. Nibelung-Kaoline-Black band fluit clay - the new key-horizon in the carboniferous system of the Ruhr coal field

    Energy Technology Data Exchange (ETDEWEB)

    Burger, K.; Otte, M.U. (Bergbau A.G. Lippe, Gelsenkirchen (Germany, F.R.). Abt. Markscheidewesen); Pfisterer, W. (Bergbau A.G. Lippe, Herne (Germany, F.R.). Hauptlaboratorium)

    1979-10-01

    Based upon the stratigraphic distribution of the kaoline-black-band flint clay in the carbon strata of the Ruhr, the Nibelung-Kaoline-black-band flint clay found in the upper Westphal C (Dorsten strata) is defined to be the new keyhorizon. The position of the discoveries of the kaoline-black-band flint clay, its stratigraphic positions as well as its macroscopic and microscopic characteristics together with the chemical composition are given. Investigations of the structure and minerals content show that the Nibelung-Kaolin-black-band flint clay is a new keyhorizon and is of great importance for the stratigraphy of the upper Westfal C. Its position within the system is represented by strata sections.

  15. Long-Chain Diacrylate Crosslinkers and Use of PEG Crosslinks in Poly(potassium acrylate-acrylic acid)/Kaolin Composite Superabsorbents

    OpenAIRE

    Koroush Kabiri; Siavash Nafisi; Mohammad jalaledin Zohuriaan-Mehr; Ali Akbar Yousefi

    2013-01-01

    Long-chain diacrylate crosslinkers based on linear α,ω-diols were synthesized and characterized using FTIR and 1H NMR spectroscopy. The highest reaction yield (99.5%) was due to polyethylene glycol diacrylate 1000 (PEGDA-1000). Then, kaolin-containing poly(potassium acrylate-acrylic acid) superabsorbent composites and kaolin-free counterparts were synthesized using PEGDA-1000.The effect of the crosslinker concentration on swelling, rheological and thermo-mechanical properties was investigated...

  16. Cure characteristics, crosslink density and degree of filler dispersion of kaolin-filled natural rubber compounds in the presence of alkanolamide

    Science.gov (United States)

    Surya, I.; Hayeemasae, N.; Ginting, M.

    2018-03-01

    The effects of alkanolamide (ALK) addition on cure characteristics, crosslink density and degree of filler dispersion of kaolin-filled natural rubber (NR) compounds were investigated. The kaolin filler was incorporated into NR compounds with a fixed loading, 30.0 phr. The ALK was prepared from Refined Bleached Deodorized Palm Stearin (RBDPS), a waste product of cooking oil production, and diethanolamine. The ALK is an oily material and added into the filled NR compounds as a rubber additive at different loadings, 0.0, 3.0, 5.0 and 7.0. The kaolin-filled NR compounds with and without ALK were vulcanized using a semi-efficient vulcanization system. It was found that ALK decreased the scorch and cure times and improved filler dispersion of the kaolin-filled NR compounds. The higher the ALK loading, the shorter were the scorch and cure times. It was also found that ALK increased the crosslink density of kaolin-filled NR compound up to 5.0 phr of loading. Due to its oily properties, The ALK acted as an internal plasticizer which decreased the minimum torque and improved the degree of kaolin dispersion in NR phases. The higher the ALK loading; the lower the minimum torque and better the filler dispersion.

  17. Integrated mined-area reclamation and land-use planning. Volume 3C. A case study of surface mining and reclamation planning: Georgia Kaolin Company Clay Mines, Washington County, Georgia

    Energy Technology Data Exchange (ETDEWEB)

    Guernsey, J L; Brown, L A; Perry, A O

    1978-02-01

    This case study examines the reclamation practices of the Georgia Kaolin's American Industrial Clay Company Division, a kaolin producer centered in Twiggs, Washington, and Wilkinson Counties, Georgia. The State of Georgia accounts for more than one-fourth of the world's kaolin production and about three-fourths of U.S. kaolin output. The mining of kaolin in Georgia illustrates the effects of mining and reclaiming lands disturbed by area surface mining. The disturbed areas are reclaimed under the rules and regulations of the Georgia Surface Mining Act of 1968. The natural conditions influencing the reclamation methodologies and techniques are markedly unique from those of other mining operations. The environmental disturbances and procedures used in reclaiming the kaolin mined lands are reviewed and implications for planners are noted.

  18. Synthesis of 4A zeolites from kaolin for obtaining 5A zeolites through ionic exchange for adsorption of arsenic

    International Nuclear Information System (INIS)

    Resmini Melo, Carolina; Gracher Riella, Humberto; Cabral Kuhnen, Nivaldo; Angioletto, Elidio; Melo, Aline Resmini; Bernardin, Adriano Michael; Rocha, Marcio Roberto da; Silva, Luciano da

    2012-01-01

    Highlights: ► We synthesize 4A zeolite from kaolin by hydrothermal reaction with sodium hydroxide. ► The 4A zeolite synthesized underwent ion exchange with calcium ions, with different parameters, to obtain 5A zeolites. ► The best 4A zeolite obtained was used as adsorbent material for arsenic ions. ► The results showed that the 5A zeolite material obtained is a good adsorber of heavy ions. - Abstract: The synthesis of adsorbing zeolite materials requires fine control of the processing variables. There are distinct process variable settings for obtaining specific desired types of zeolites. The intent of this study was to obtain 4A zeolites from kaolin in order to obtain 5A zeolites through ionic exchange with the previously synthesized zeolite. This zeolite 5A was used as an adsorbent for arsenic ions. The results obtained were satisfactory.

  19. Synthesis and characterization of ZSM-5 and calcined kaolin evaluation using the content of structure-directing

    International Nuclear Information System (INIS)

    Rodrigues, J.J.; Silva, V.J. da; Rodrigues, M.G.F.

    2012-01-01

    This study aims to evaluate the effect of the structure-directing content, tetrapropylammonium bromide, on the structural and morphological characteristics of ZSM-5 zeolite obtained using calcined kaolin as silicon and aluminum. The samples were characterized by XRD, EDX, SEM and Physics Adsorption N 2 . Trough X ray diffraction patterns was possible to observed the formation of the structure of ZSM-5 with intense peaks and well-defined characteristic of crystalline. The micrographs showed that the samples consist of agglomerates and/or aggregates of particles characteristic of the MFI structure typical of ZSM-5 zeolite. And through the adsorption-desorption isotherms physical N2 was possible to observe that the samples show hysteresis type I typical of microporous materials with specific surface areas of 218 and 222 m 2 /g. Therefore, the use of calcined kaolin to obtain ZSM-5 zeolite was effective. (author)

  20. Influence of the type of aqueous sodium silicate on the stabilization and rheology of kaolin clay suspensions

    Science.gov (United States)

    Izak, Piotr; Ogłaza, Longin; Mozgawa, Włodzimierz; Mastalska-Popławska, Joanna; Stempkowska, Agata

    2018-05-01

    To avoid agglomeration and sedimentation of grains, ceramic slurries should be modified by stabilizers in order to increase the electrostatic interactions between the dispersed particles. In this study we present the spectral analysis of aqueous sodium silicates obtained by different synthesis methods and their influence on the rheological properties of kaolin based slurries. Infrared and Raman spectra can be used to describe the structure of silicate structural units present in aqueous sodium silicates. It was confirmed that the best stabilization results possess aqueous sodium silicates of the silicate moduli of about 2 and the optimal concentration of the used fluidizer is 0.3 wt% to the kaolin clay dry mass. One of the most important conclusions is that the synthesis method of the fluidizer has no significant effect on its stabilization properties but used medium does create adequate stabilization mechanism depending on the silicate structures present in the sodium silicate solution.

  1. Contrasting respirable quartz and kaolin retention of lecithin surfactant and expression of membranolytic activity following phospholipase A2 digestion.

    Science.gov (United States)

    Wallace, W E; Keane, M J; Mike, P S; Hill, C A; Vallyathan, V; Regad, E D

    1992-11-01

    Respirable-sized quartz, a well-established fibrogenic mineral dust, is compared with kaolin in erythrocyte hemolysis assays after treatment with saline dispersion of dipalmitoyl phosphatidylcholine, a primary phospholipid component of pulmonary surfactant. Both dusts are rendered inactive after treatment, but the membranolytic activity is partly to fully restored after treatment with phospholipase A2, an enzyme normally associated with cellular plasma membranes and lysosomes. Phospholipid-coated dusts were incubated for periods of 2-72 h at a series of applied enzyme concentrations, and the adsorbed lipid species and hemolytic activity were quantitated at each time for both dusts. Surfactant was lost more readily from quartz than from kaolin, with consequent more rapid restoration of mineral surface hemolytic activity for quartz. Interactions of surfactant and mineral surface functional groups responsible for the mineral-specific rate differences, and implications for determining the mineral surface bioavailability of silica and silicate dusts, are discussed.

  2. Use of kaolin as a potential low-cost adsorbent for the removal of malachite green from colored effluents

    Energy Technology Data Exchange (ETDEWEB)

    Foletto, E.L.; Caponi, N.; Collazzo, G.C.; Jahn, S.L.; Dotto, G.L.; Mazutti, M.A. [Universidade Federal de Santa Maria (UFSM), RS (Brazil)

    2016-07-01

    Full text: This study investigated the potential of raw kaolin as a low-cost adsorbent for the removal Malachite Green (MG) from colored effluents. The morphology, chemical structure and the surface properties of the adsorbent were investigated by characterization techniques such as X-ray diffraction, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, X-ray fluorescence spectroscopy and scanning electron microscopy. A possible technological application of kaolin is the MG removal from aqueous media, which was investigated by batch adsorption experiments. The adsorption kinetics was studied using the pseudo-first order, pseudo-second order and Elovich models. The adsorption isotherms were studied using Langmuir, Freundlich and Sips models. Maximum adsorption capacity was found to be 128 mg g-1, and this satisfactory result may be associated to some properties of adsorbent. Therefore, the results of this investigation revealed that kaolin can be utilized as a promising low-cost adsorbent to remove MG from colored effluents. (author)

  3. Magnetic zeolites a and p synthesized from kaolin: synthesis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Bessa, R.A.; Oliveira, C.P.; Nascimento, R.F.; Bohn, F.; Loiola, A.R. [Universidade Federal do Ceara (UFCE), CE (Brazil)

    2016-07-01

    Full text: Zeolites are hydrated aluminosilicates of open chain, formed by silica and alumina tetrahedral structures linked by common oxygen atoms, generating interconnected pores and cages with molecular dimensions and well defined sizes that limit matter transference between internal surface and application medium. They can be found naturally or synthesized using different aluminum and silicon sources that may modify the produced zeolite. Their industrial application has grown enormously over the last century. However, a big issue that still remains is the difficulty in retrieving zeolite powders when used in aqueous media. This work reports the use of kaolin as an alternative raw material for zeolite syntheses by means of hydrothermal route and subsequent preparation of magnetic composites through magnetite impregnation. The syntheses of two different zeolites were carried out by mixing appropriate amounts of metakaolin (kaolin previously calcined at 600 deg C for 2 h), sodium metasilicate and sodium hydroxide solution, aged for 18 h and heated at 100 °C for 4-48 h. After these processes, the final materials were washed several times with distilled water, filtered and dried at 80 deg C for 12 h. Magnetic composites were prepared by impregnating the zeolites with of Fe3O4 nanoparticles (NP) synthesized by the partial oxidation and precipitation of Fe2+ ions. The obtained materials were characterized by X-ray diffraction, scanning electron microscopy, FTIR spectroscopy and magnetization measurements. The results of XRD and FTIR provide evidence of the success in the synthesis of both zeolites A and P as well as Fe3O4. Subsequently, composites were formed by mixtures of zeolite A + NP and zeolite P + NP. The existence of secondary crystalline phases was also confirmed. However, it did not interfered significantly in the results as these phases appear as minor amounts and are most likely residues from the clay used as the main silica and alumina sources. Scanning

  4. How are macroinvertebrates of slow flowing lotic systems directly affected by suspended and deposited sediments?

    Energy Technology Data Exchange (ETDEWEB)

    Kefford, Ben J., E-mail: ben.kefford@rmit.edu.a [Biotechnology and Environmental Biology, School of Applied Sciences, RMIT University, PO Box 71, Bundoora, Victoria 3083 (Australia); Zalizniak, Liliana [Biotechnology and Environmental Biology, School of Applied Sciences, RMIT University, PO Box 71, Bundoora, Victoria 3083 (Australia); Dunlop, Jason E. [Department of Environment and Resource Management (DERM), 120 Meiers Rd, Indooroopilly, Queensland 4068 (Australia); Smart Water Research Facility, Griffith University, Queensland (Australia); Nugegoda, Dayanthi [Biotechnology and Environmental Biology, School of Applied Sciences, RMIT University, PO Box 71, Bundoora, Victoria 3083 (Australia); Choy, Satish C. [Department of Environment and Resource Management (DERM), 120 Meiers Rd, Indooroopilly, Queensland 4068 (Australia)

    2010-02-15

    The effects of suspended and deposited sediments on the macroinvertebrates are well documented in upland streams but not in slower flowing lowland rivers. Using species found in lowland lotic environments, we experimentally evaluate mechanisms for sediments to affect macroinvertebrates, and in one experiment whether salinity alters the effect of suspended sediments. Suspended kaolin clay reduced feeding of Ischnura heterosticta (Odonata: Coenagrionidae) at high turbidity (1000-1500 NTU) but had no effects on feeding of Hemianax papuensis (Odonata: Aeshnidae) and Micronecta australiensis (Hemiptera: Corixidae). In freshwater (0.1 mS/cm), survival of Ischnura aurora was poor in clear water, but improved with suspended kaolin. Growth and feeding of I. aurora were unaffected by suspended sediments and salinity. Burial (1-5 mm) of eggs with kaolin or sand reduced hatching in Physa acuta (Gastropoda: Physidae), Gyraulus tasmanica (Gastropoda: Planorbidae) and Chironomus cloacalis (Diptera: Chironomidae). Settling sediments may pose greater risk to lowland lotic invertebrates than suspended sediments. - Sediment deposition may be more directly detrimental to macroinvertebrates of lowland rivers than suspended sediments.

  5. Influence of inert fillers on shrinkage cracking of meta-kaolin geo-polymers

    International Nuclear Information System (INIS)

    Kuenzel, C.; Boccaccini, A.R.

    2012-01-01

    Geo-polymers contain a network of tetrahedral coordinated aluminate and silicate, and are potential materials to immobilize/encapsulate nuclear wastes. They can exhibit shrinkage cracking when water is removed by drying, and in order to use geo-polymers for waste encapsulation this effect needs to be investigated and controlled. In this study, six different fillers were mixed with meta-kaolin and sodium silicate solution at high pH to form geo-polymers, and the influence of filler addition on mechanical properties has been determined. The fillers used were Fe 2 O 3 , Al 2 O 3 , CaCO 3 , sand, glass and rubber and these do not react during geo-polymerisation reactions. Geo-polymers were prepared containing 30 weight percent of filler. The mechanical properties of the geo-polymers were influenced by the type of filler, with low density fillers increasing mortar viscosity. Geo-polymer samples containing fine filler particles exhibited shrinkage cracking on drying. This was not observed when coarser particles were added and these samples also had significantly improved mechanical properties. (authors)

  6. Edaravone reduces astrogliosis and apoptosis in young rats with kaolin-induced hydrocephalus.

    Science.gov (United States)

    Garcia, Camila Araújo Bernardino; Catalão, Carlos Henrique Rocha; Machado, Hélio Rubens; Júnior, Ivair Matias; Romeiro, Thais Helena; Peixoto-Santos, José Eduardo; Santos, Marcelo Volpon; da Silva Lopes, Luiza

    2017-03-01

    We investigated the possible neuroprotective effects of the free radical scavenger edaravone in experimental hydrocephalus. Seven-day-old Wistar rats were divided into three groups: control group (C), untreated hydrocephalic (H), and hydrocephalic treated with edaravone (EH). The H and EH groups were subjected to hydrocephalus induction by 20% kaolin intracisternal injection. The edaravone (20 mg/kg) was administered daily for 14 days from the induction of hydrocephalus. All animals were daily weighed and submitted to behavioral test and assessment by magnetic resonance imaging. After 14 days, the animals were sacrificed and the brain was removed for histological, immunohistochemical, and biochemical studies. The gain weight was similar between groups from the ninth post-induction day. The open field test performance of EH group was better (p  0.01), germinal matrix (p > 0.05), and cerebral cortex (p > 0.05), as compared to H group. We have demonstrated that administration of edaravone for 14 consecutive days after induction of hydrocephalus reduced astrocyte activity and that it has some beneficial effects over apoptotic cell death.

  7. Effect of temperature on volume change behaviour of statically compacted kaolin clay

    Directory of Open Access Journals (Sweden)

    Ileme Ogechi

    2016-01-01

    Full Text Available Several soils are subjected to high temperature due to the environment where they are located or activities around them. For instance, upper layer of soils in tropical regions, soils around geothermal structures, clay barriers around nuclear waste repository systems. Numerous studies have pointed out that high temperature affects the hydro-mechanical properties of soils. Notwithstanding already existing studies, the influence of temperature on soils is still a challenge, as most of these studies are soil specific and cannot be inferred as the behaviour of all soils. This paper presents an experimental study on the influence of temperature on the volume change behaviour of statically compacted kaolin clay. Compacted samples were tested at varying temperatures using a suction controlled oedometer cell. The influence of temperature on the magnitude of volumetric strain occurring during mechanical and thermal loading was investigated. The study showed that an increase in temperature increased the magnitude of volumetric strain of the soil on loading. Additionally, the results presented in the light of LC curve showed that an increase in temperature resulted in the contraction and a change in the position of the LC curve.

  8. Mechanical properties of anorthite based ceramics prepared from kaolin DD2 and calcite

    Energy Technology Data Exchange (ETDEWEB)

    Harabi, A.; Zaiou, S.; Guechi, A.; Foughali, L.; Harabi, E.; Karboua, N.-E.; Zouai, S.; Mezahi, F.-Z.; Guerfa, F., E-mail: harabi52@gmail.com, E-mail: Zaiou_21@yahoo.fr, E-mail: guechia@yahoo.fr, E-mail: semouni84@gmail.com, E-mail: kanour17@yahoo.fr, E-mail: foughali_lazhar@yahoo.fr, E-mail: zouaisouheila@yahoo.fr, E-mail: mezahif@yahoo.fr [Ceramics Lab., Faculty of Exact Science, Physics Department, Mentouri University of Constantine (Algeria)

    2017-07-15

    Good quality ceramics costs a lot that has limited their use in developing countries. This work was devoted to prepare low-cost and good quality anorthite based ceramics. The proposed composition was 80 wt% kaolin (DD2 type) and 20 wt% calcium oxide (CaO). The choice of these raw materials was dictated by their natural abundance coupled with a modified milling system, as another interesting advantage. Previous studies have shown that a simple vibratory multidirectional milling system using bimodal distribution of highly resistant ceramic milling elements has been successfully applied for obtaining fine powders. The influence of the relatively lower sintering temperature, ranging from 800 to 1100 °C, on the porosity and the average pore size (APS) have been investigated. The APS and the porosity values of samples sintered at 950 °C were about 1 μm and 4%, respectively. The best Vickers microhardness and 3-point bending strength values for these sintered samples, using this proposed milling system, were 7.1 GPa and 203 MPa, respectively. Finally, the crystalline phase evolution during heat treatment was investigated by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy techniques. (author)

  9. Hydrothermal synthesis of zeolite T from kaolin using two different structure-directing agents

    Science.gov (United States)

    Arshad, Sazmal E.; Lutfor Rahman, M.; Sarkar, Shaheen M.; Yusslee, Eddy F.; Patuwan, Siti Z.

    2018-01-01

    Zeolite T was synthesized from the molar chemical composition of 1SiO2:0.04Al2O3:0.26Na2O:0.09K2O:14H2O in the form of a homogenous milky solution in the presence of the two different structure-directing agents TMAOH and TEAOH respectively. Modification of the composition of silica was undertaken using metakaolin from calcined kaolin at 750 °C for 4 h, while the molar composition of each different SDA was variated from 0.05, 0.10, 0.15, 0.20 and 0.25. The homogenous mixture was left at room temperature for 24 h before undergoing hydrothermal synthesis at 100 °C for 168 h. The synthesized samples were filtered and aged at 120 °C for 2 h and each sample was calcined at high temperatures (545 °C for TMAOH and 520 °C for TEAOH) for template removal before characterization using XRD and SEM. Crystallization of the zeolite T in its major form only took place at a molar ratio of 0.10 of TMAOH, while TEAOH showed the species evolution of zeolite T into zeolite L and W for other molar ratios.

  10. Equilibrium, kinetic and thermodynamic studies of adsorption of Th(IV) from aqueous solution onto kaolin

    International Nuclear Information System (INIS)

    Hongxia Zhang; Zhiwei Niu; Zhi Liu; Zhaodong Wen; Weiping Li; Xiaoyun Wang; Wangsuo Wu

    2015-01-01

    The kinetics and thermodynamics of the adsorption of Th(IV) on the kaolin were studied by using batch method. In addition, the experimental data were studied by dynamic and thermodynamic models. The results showed that the adsorption capacity of the adsorbent increased with increasing temperature and solid liquid ratio, but decreased with increasing initial Th(IV) ion concentration, and the best fit was obtained for the pseudo-second-order kinetics model. The calculated activation energy for adsorption was about 45 kJ/mol, which indicated the adsorption process to be chemisorption. The adsorption isotherm data could be well described by the Langmuir as well as Dubinin-Radushkevich model. The mean free energy (E) of adsorption was calculated to be about 15 kJ/mol. The thermodynamic data calculated showed that the adsorption was spontaneous and enhanced at higher temperature. Considering kinetics and equilibrium studies, the adsorption on the sites was the rate-limiting step and that adsorption was mainly a chemisorption process through cation exchange. (author)

  11. Effect of Compatibilizer on the Dynamic Mechanical and Electrical Properties of Kaolin Clay Reinforced EPDM Rubber

    International Nuclear Information System (INIS)

    Sarkhel, G.; Manjhi, S.

    2013-01-01

    Industrial pollution issue and dark colour of carbon black, clay based non black filler are getting more importance for reinforcing elastomer. EPDM-Kaolin composites with various maleated EPDM concentration have been prepared by mixing on a two roll mill. The rheometry data showed the optimum cure time increases with increasing compatibilizer concentration without decreasing torque value indicating that acidic functional groups comes from compatibilizer could retard cure rate and increase the optimum cure time rather than change in the ultimate cure state. As the filler concentration increases, the edge to edge and face to edge interaction between filler and EPDM increases and the free volume between EPDM molecules is reduced, the storage modulus increases. Moreover, the dynamic mechanical analysis also showed the increase in glass transition temperature with increase in filler concentration due to the inter-tubular diffusion of EPDM inside the clay. It was also observed that with increasing filler concentration, the resistivity and dielectric strength decreases and moreover with increasing compatibilizer concentration the resistivity decreases due to better dispersion of filler helps to build conduction path. The morphological study also revealed that homogeneity of filler dispersion increases with increase in compatibilizer concentration. (author)

  12. Smart Natural Fiber Reinforced Plastic (NFRP) Composites Based On Recycled Polypropylene in The Presence Kaolin

    Science.gov (United States)

    Suharty, N. S.; Ismail, H.; Diharjo, K.; Handayani, D. S.; Lestari, W. A.

    2017-07-01

    Composites contain double filler material which act as reinforcement and flame retardants of recycled polypropylene (rPP)/kaolin(Kao)/palm oil empty bunch fiber (PEBF) have been succesfully prepared. The composites were synthesized through reactively solution method, using coupling agent PP-g-AA and compatibilizer DVB. The effect of double filler [Kao/PEBF] were investigated flexural strength (FS), inflammability, and morphology. Mechanical testing result in accordance to ASTM D790, the FS of rPP/DVB/PP-g-AA/Kao+ZB/PEBF composite was 48% higher than that of rPP matrix. Moreover, flexural modulus (FM) was significantly improved by 56% as compared to that of rPP matrix. The scanning electron images (SEM) shown good dispersion of [Ka/PEBF] and good filler-matrix interaction. The inflammability testing result which is tested using ASTM D635, showed that the flame resistance of rPP/DVB/PP-g-AA/Kao+ZB/PEBF composite was improve by increasing of time to ignition (TTI) about 857% and burning rate (BR) decreasing to 66% compared to the raw material rPP matrix. In the same time, the addition of 20% (w/w) PEBF as a second filler to form rPP/DVB/PP-g-AA/Kao+ZB/PEBF composites (F5) is able to increase: the FS by 17.5%, the FM by 19%, the TTI by 7.6% and the BR by 3.7% compared to the composite without PEBF (F2).

  13. The Effects of Flocculation on the Propagation of Ultrasound in Dilute Kaolin Slurries.

    Science.gov (United States)

    Austin; Challis

    1998-10-01

    A broadband ultrasonic spectrometer has been used to measure ultrasonic attenuation and phase velocity dispersion as functions of frequency in kaolin suspensions over a range of solid volume fractions from phi = 0.01 to phi = 0.08 and over a pH range from 3 to 9. The Harker and Temple theory was used to simulate ultrasound propagation in the suspension, using measured slope viscosity, particle size, and size distribution. Simulated results for ultrasonic attenuation and phase velocity agree well with measured values. Both sets of results agree well and show that for volume fractions above phi approximately 0.05 attenuation and velocity dispersion increase for increasing floc size, whereas for volume fractions below phi approximately 0.05 attenuation and velocity dispersion both decrease. It is proposed that the mechanism for this change in behavior around phi approximately 0.05 involves changes in floc density and floc size distribution with phi and pH. Copyright 1998 Academic Press.

  14. Characterization of kaolin wastes from kaolin mining industry from the amazon region as raw material for pozzolans production; Caracterizacao dos residuos cauliniticos das industrias de mineracao de caulim da amazonia como materia-prima para producao de pozolanas de alta reatividade

    Energy Technology Data Exchange (ETDEWEB)

    Barata, M.S.; Angelica, R.S., E-mail: msb@amazon.com.br, E-mail: angelica@ufpa.br [Instituto de Geociencias, Universidade Federal do Para, Belem, PA (Brazil)

    2012-01-15

    Capim and Jari are the two most important kaolin mining districts of the Brazilian Amazon region. They encompass the major Brazilian reserves of high quality kaolin for the paper coating industry. The kaolin is mined and processed by three major companies responsible for about 500,000 ton of a residue mainly composed of kaolinite. The wastes come mainly from the centrifugation phase of the kaolin beneficiation process and their final destinations are huge sedimentation basins that occupy large areas. The main purpose of this work is to evaluate the physical, chemical and mineralogical characteristics of the kaolin wastes processed from the Capim and Jari region, in order to obtain meta kaolinite, a high reactive pozzolans for the cement industry. When incorporated to ordinary Portland cement such pozzolans increases the concrete and mortars performance. All the residues studied in this work were characterized by means of: X-ray diffraction analysis, differential thermal analysis, infrared spectroscopy, scanning electron microscopy, X-ray fluorescence spectrometry and laser diffraction. Both residues are mainly constitutes by at least 92% of low granulometry kaolinite with specific surface area above 8 m2 /g and mean diameter below 1 {mu}m. Free silica (quartz) contents are below 3%. The high concentration of kaolinite in these residues dispenses rigid control parameters for removal of impurities usually employed in pozzolans production. The Jari kaolin exhibits high disordered kaolinite in comparison with the high ordered kaolinite of the Capim region and gives rise to higher desidroxilation degree at lower temperatures. It points to energy saving and reducing costs during the production of a pozzolans. The results are satisfactory and reveal that both kaolin wastes are excellent raw material for the production of high reactive meta kaolin. (author)

  15. Detection of tPA-Induced Hyperfibrinolysis in Whole Blood by RapidTEG, KaolinTEG, and Functional FibrinogenTEG in Healthy Individuals

    DEFF Research Database (Denmark)

    Genét, Gustav Folmer; Ostrowski, Sisse Rye; Sørensen, Anne Marie

    2012-01-01

    hyperfibrinolysis, as compared to standard KaolinTEG, is unknown. To investigate this, the ability of RapidTEG, KaolinTEG, and functional fibrinogenTEG (FFTEG) to detect tPA-induced (tissue plasminogen activator) lysis in whole blood from healthy individuals was investigated. Our hypothesis was that the initial...... powerful clot formation in the RapidTEG assay would reduce the sensitivity as compared to the normally used KaolinTEG assay. We also evaluated the FFTEG assay. Methods: In vitro comparison of the sensitivity of RapidTEG, KaolinTEG, and FFTEG to 1.8 nmol/L tPA in citrated whole blood (299 ± 23 ng/mL plasma......) induced hyperfibrinolysis in 10 healthy individuals and duplicate titration of the tPA whole blood (WB) concentration from 0.09 to 7.2 nmol/L (14-1144 ng/mL plasma) in 1 healthy donor. Results: At 1.8 nmol/L tPA, KaolinTEG, RapidTEG, and FFTEG all detected fibrinolysis but with different sensitivities...

  16. Investigation of the effect of kaolin and tissue factor-activated citrated whole blood, on clot forming variables, as evaluated by thromboelastograph

    DEFF Research Database (Denmark)

    Johansson, Per Ingemar; Bochsen, L.; Andersen, S.

    2008-01-01

    ), and maximum clot strength (amplitude [MA]) were evaluated, together with day-to-day variation, the coefficient of variance (CV%), and the effect of citrate storage time. RESULTS: Clot formation variables were equally affected by TF 1:17,000 and kaolin activation, whereas R was significantly longer when TF 1......:42,500 was used. The CV for the different variables varied from 3 to 13 percent with no significant differences between assays. Storage of citrated WB significantly affected the TEG variables in a hypercoagulable direction. Only the R, however, was significantly affected (12%) when samples rested for 0 and 30...... minutes were evaluated with kaolin as the activator. CONCLUSION: The TEG assays evaluated were reproducible and present with an acceptable CV% for routine clinical practice. Kaolin and TF 1:17,000 equally affected the clot formation variables. Storage of WB for up to 30 minutes in citrate did not, except...

  17. Effects of using kaolin waste and granite waste as raw materials for the production of low-water absorption ceramic tiles

    International Nuclear Information System (INIS)

    Freires, H.P.; Argonz, R.; Nogueira, R.E.F.Q.; Sasaki, J.M.; Sales, J.C.

    2012-01-01

    This study aims to evaluate the potential of co-use of granite waste (Rain Forest) and kaolin waste as raw material for the manufacture of ceramic coating of low water absorption. Raw materials were characterized by X-ray diffraction. Kaolin residue was added to the residue of granite in the following proportions (in wt%): 0, 10, 20, 30, 40 and 50%. Specimens were fabricated by uniaxial pressing and fired at 1175,1200 and 1225 deg C. Studies of firing linear shrinkage, water absorption, apparent porosity, apparent density and tensile bending test (or rupture modulus) were conducted. The temperature of 1225 deg C allowed the use of a mixture of 50% granite residue and 50% kaolin residue. Ceramic parts made from that mixture exhibited the maximum values required by the Brazilian Standard NBR 13818 for water absorption, shrinkage and density. (author)

  18. Sample size clay kaolin of primary in pegmatites regions Junco Serido - PB and Equador - RN; Granulometria de argila caulim primario dos pegmatitos nas regioes do Junco do Serido - PB e Equador - RN

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, M.F.; Sousa, J.B.M.; Sales, L.R.; Silva, P.A.S.; Lima, A.D.D., E-mail: mauro.meyer@ifrn.edu.br [Instituto Federal do Rio Grande do Norte (IFRN), RN (Brazil)

    2016-07-01

    Kaolin is a clay formed mainly of kaolinite resulting from feldspar weathering or hydrothermal. This study aims to investigate the way of occurrence, kaolin particle size of the pegmatites of the Borborema Province Pegmatitic in the regions of Junco do Serido-PB and Ecuador-RN. These variables were analyzed considering granulometric intervals obtained from wet sieving of samples of pegmatite mines in the region. Kaolin was received using sieves of 200, 325, 400 and 500 mesh and the sieve fractions retained by generating statistical parameters histograms. kaolin particles are extremely fine and pass in its entirety through 500 mesh sieve. The characterization of minerals in fine fractions by diffraction of X-rays showed that the relative amount of sericite in fractions retained in sieves 400 and 500 mesh impairing the whiteness and mineralogical texture kaolin production. (author)

  19. Particle morphology and mineral structure of heavy metal-contaminated kaolin soil before and after electrokinetic remediation.

    Science.gov (United States)

    Roach, Nicole; Reddy, Krishna R; Al-Hamdan, Ashraf Z

    2009-06-15

    This study aims to characterize the physical distribution of heavy metals in kaolin soil and the chemical and structural changes in kaolinite minerals that result from electrokinetic remediation. Three bench-scale electrokinetic experiments were conducted on kaolin that was spiked with Cr(VI) alone, Ni (II) alone, and a combination of Cr(VI), Ni(II) and Cd(II) under a constant electric potential of 1VDC/cm for a total duration of 4 days. Transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analyses were performed on the soil samples before and after electrokinetic remediation. Results showed that the heavy metal contaminant distribution in the soil samples was not observable using TEM and EDX. EDX detected nickel and chromium on some kaolinite particles and titanium-rich, high-contrast particles, but no separate phases containing the metal contaminants were detected. Small amounts of heavy metal contaminants that were detected by EDX in the absence of a visible phase suggest that ions are adsorbed to kaolinite particle surfaces as a thin coating. There was also no clear correlation between semiquantitative analysis of EDX spectra and measured total metal concentrations, which may be attributed to low heavy metal concentrations and small size of samples used. X-ray diffraction analyses were aimed to detect any structural changes in kaolinite minerals resulting from EK. The diffraction patterns showed a decrease in peak height with decreasing soil pH value, which indicates possible dissolution of kaolinite minerals during electrokinetic remediation. Overall this study showed that the changes in particle morphology were found to be insignificant, but a relationship was found between the crystallinity of kaolin and the pH changes induced by the applied electric potential.

  20. Radiological impacts of the usability of Dolerite and Kaolin as raw materials for construction works in Abia State, Nigeria

    International Nuclear Information System (INIS)

    Enyinna, P.I.; Avwiri, G. O.

    2011-01-01

    This research study is aimed at carrying out radiometric analyses of the natural radioactivity resulting from the presence of radionuclides in dolerite and kaolin which are raw materials widely used in construction works. The activity concentrations of the identified natural radionuclides of 226 Ra, 228 Ra and 40 K in 40 samples of these solid minerals collected from 4 mining sites were determined by gamma ray spectroscopic technique using a well calibrated [NaI(Tl)] detector. The mean values of the activity concentrations of 226 Ra, 228 Ra and 40 K for the dolerite samples were found to be 10.989Bq/kg, 6.956Bq/kg, 723.253Bq/kg and 10.735Bq/kg, 6.175Bq/kg, 714.895Bq/kg respectively (for the 2 dolerite mining sites); and for the kaolin samples, 8.507Bq/kg, 7.33Bq/kg, 87.511Bq/kg and 8.416Bq/kg, 7.354Bq/kg, 86.727Bq/kg respectively (for the 2 kaolin mining sites). The radium equivalent activity, the absorbed dose rate, the equivalent dose rate, the external and internal hazard indices, the annual outdoor and indoor effective dose rates were computed and compared with international radiological standards to ascertain if these minerals pose any radiological hazard. The results obtained were found to conform within the limits of acceptable international radiological standards and may not pose any immediate threat to the public and users of these two solid minerals for construction works.

  1. Mineralogical characterization and beneficiation study of kaolin from Equador (RN) and Junco do Serido (PB) to increase the brightness index

    International Nuclear Information System (INIS)

    Campos, V.M.J.S.; Bertolino, L.C.; Alves, O.C.

    2017-01-01

    Kaolin is a rock composed mainly of kaolinite. It is used in many industrial segments, such as paper and ceramics. However, for these uses it is necessary to submit the ore to appropriate beneficiation, which generally involves magnetic separation and chemical bleaching, aiming to remove iron oxide and hydroxide, raising brightness index. This work reports the mineralogical characterization and analysis of the beneficiation of three samples of kaolin, two from Equador (Rio Grande do Norte - RN) and the third from Junco do Serido (Paraiba - PB). The samples were submitted to granulometric classification in sieve of 44 μm, magnetic separation in a magnetic induction of 14000 gauss, and chemical bleaching with sodium dithionite during 240 min. The processes were divided into two beneficiation routes. X-ray diffraction, chemical analysis by X-ray fluorescence and scanning electron microscopy were used for mineralogical characterization of the ore and measurement of the brightness index, while electron paramagnetic resonance was applied to study the variation of iron oxides and hydroxides during beneficiation. The results indicate that just 30 min of chemical bleaching without magnetic separation was sufficient to increase the brightness index from 78.2 to 90.2% and from 91.3 to 95.7% in the two samples from Equador (RN) and from 86.9 to 90.4% in the sample from Junco do Serido (PB). The magnetic separation, although causing a small increase in the brightness index, was inefficient for removal of iron oxides and hydroxides. The results indicated no need for using magnetic separation in plants for beneficiation of kaolin from these two locations, providing the reduction of production costs allowing better exploitation of the ore. (author)

  2. Particle morphology and mineral structure of heavy metal-contaminated kaolin soil before and after electrokinetic remediation

    International Nuclear Information System (INIS)

    Roach, Nicole; Reddy, Krishna R.; Al-Hamdan, Ashraf Z.

    2009-01-01

    This study aims to characterize the physical distribution of heavy metals in kaolin soil and the chemical and structural changes in kaolinite minerals that result from electrokinetic remediation. Three bench-scale electrokinetic experiments were conducted on kaolin that was spiked with Cr(VI) alone, Ni (II) alone, and a combination of Cr(VI), Ni(II) and Cd(II) under a constant electric potential of 1 VDC/cm for a total duration of 4 days. Transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analyses were performed on the soil samples before and after electrokinetic remediation. Results showed that the heavy metal contaminant distribution in the soil samples was not observable using TEM and EDX. EDX detected nickel and chromium on some kaolinite particles and titanium-rich, high-contrast particles, but no separate phases containing the metal contaminants were detected. Small amounts of heavy metal contaminants that were detected by EDX in the absence of a visible phase suggest that ions are adsorbed to kaolinite particle surfaces as a thin coating. There was also no clear correlation between semiquantitative analysis of EDX spectra and measured total metal concentrations, which may be attributed to low heavy metal concentrations and small size of samples used. X-ray diffraction analyses were aimed to detect any structural changes in kaolinite minerals resulting from EK. The diffraction patterns showed a decrease in peak height with decreasing soil pH value, which indicates possible dissolution of kaolinite minerals during electrokinetic remediation. Overall this study showed that the changes in particle morphology were found to be insignificant, but a relationship was found between the crystallinity of kaolin and the pH changes induced by the applied electric potential.

  3. X-ray shielding behaviour of kaolin derived mullite-barites ceramic

    Science.gov (United States)

    Ripin, A.; Mohamed, F.; Choo, T. F.; Yusof, M. R.; Hashim, S.; Ghoshal, S. K.

    2018-03-01

    Mullite-barite ceramic (MBC) is an emergent material for effective shielding of redundant ionizing radiation exposure. The composition dependent mechanical, thermal, and microstructure properties of MBC that makes MBC a high performing novel radiation shielding candidate remained unexplored. This paper examines the possibility of exploiting Malaysian kaolin (AKIM-35) and barite (BaSO4) derived ceramic (MBC) system for X-ray shielding operation. Using conventional pressing and sintering method six ceramic samples are prepared by mixing AKIM-35 with barite at varying contents (0, 10, 20, 30, 40 and 50 wt%). Synthesized pressed mixtures are calcined at 400 °C for 30 min and then sintered to 1300 °C for 120 min at a heating rate of 10 °C/min. Sintered samples are characterized via X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), lead equivalent (LE), uniformity and dose reduction analyses. XRD pattern of prepared ceramics revealed the presence of monoclinic barium alumino-silicate (BAS) and orthorhombic mullite as major shielding phases together with other minor phase of barite and hexagonal quartz (SiO2) structures. Furthermore, FESEM images of ceramics (between 0 and 30 wt%) displayed the existence of compacted monoclinic plate of BAS and acicular mullite morphology (ceramics at 40 and 50 wt%). Radiation tests displayed the capacity of ceramics (at 0 and 10 wt%) to shield the X-ray radiation emanated at tube potential range of 50-120 kV. The highest radiation attenuation is ascertained at 70 kV where the dose is reduced remarkably between 99.11% and 97.42%. Ceramics at 0 and 10 wt% demonstrated the highest lead (Pb) equivalent thickness (LE) of 0.44 mm and 0.34 mm, respectively. It is established that such MBC may contribute towards the development of shielding material against ionizing radiation in diagnostic radiology (X-ray) dose range.

  4. Synthesis, characterization and application of nanozeolite NaX from Vietnamese kaolin

    International Nuclear Information System (INIS)

    Ngoc, Don Ta; Pham, Thanh Huyen; Hong Nguyen, Khanh Dieu

    2013-01-01

    This paper presents the results of synthesis of nanozeolite NaX from Vietnamese kaolin. Influence factors on the control of crystal sizes and application of synthesized materials as adsorbent for organic compound are discussed. The results show that there are several factors that influence the synthesis. When water content in gel increases, crystal size of NaX increases sharply. The increase of alkaline and silica contents increases the crystallinity and decreases the particle size of nano NaX, and the particle size reaches the minimum at Na 2 O/Al 2 O 3 = 5.0 and SiO 2 /Al 2 O 3 = 4.0. Crystal sizes formed at low crystallizing temperature are smaller than those formed at higher temperature. Ageing time and crystallizing time strongly influence the crystallinity and crystal size, which is related to the number of crystal seeds formed during ageing period, the growth of seed and the partial solubility of crystal at maximum formation. Nano NaX was characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) adsorption, Fourier transform infrared (FTIR) and simultaneous thermogravimetry–differential scanning calorimetry (TG/DSC). At optimized synthesis conditions, nano NaX has surface area of 573 m 2 g −1 with external surface area of 92 m 2 g −1 , pore size distribution at 0.81 and 10.8 nm, average crystal size of 25 nm and thermal stability up to 789 °C. This material can adsorb cumene rapidly with high adsorption capacity and stability. (paper)

  5. Synthesis of kaolin supported nanoscale zero-valent iron and its degradation mechanism of Direct Fast Black G in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xiaoying; Chen, Zhengxian [Fujian Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province (China); Zhou, Rongbing [Institute of Environ Sci and Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018 (China); Chen, Zuliang, E-mail: Zuliang.chen@unisa.edu.au [Fujian Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province (China); Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia)

    2015-01-15

    Graphical abstract: UV–visible spectra of DFBG solution using K-nZVI (1:1) nanoparticles. (a) Before reaction; (b) during reaction; (c) after reaction. - Highlights: • Kaolin-supported Fe{sup 0} nanoparticle (K-nZVI) was synthesized. • Degradation of Direct Fast Black by K-nZVI was studied. • K-nZVI was characterized by SEM, XRD, UV and FIIR. • Degradation mechanism of Direct Fast Black was proposed. - Abstract: Calcinated kaolin supported nanoscale zero-valent iron (K-nZVI) was synthesized and used for the removal of tetrad azo-group dye-Direct Fast Black G (DFBG) from aqueous solution. The results demonstrated that after reacting for 10 min with an initial concentration of DFBG 100 mg L{sup −1} (pH 9.49), 78.60% of DFBG was removed using K-nZVI, while only 41.39% and 12.56% of DFBG were removed using nZVI and kaolin, respectively. K-nZVI with a mass ratio of nZVI nanoparticles versus kaolin at 1:1 was found to have a high degree of reactivity. Furthermore, scanning electron microscopy (SEM) confirmed that nZVI was better dispersed when kaolin was present. XRD patterns indicated that iron oxides were formed after reaction. Fourier transforms infrared spectra (FTIR) and UV–visible demonstrated that the peak in the visible light region of DFBG was degraded and new bands were observed. Kinetics studies showed that the degradation of DFBG fitted well to the pseudo first-order model. The degradation of DFBG by K-nZVI was based on its adsorption onto kaolin and iron oxides, and subsequently reduction using nZVI was proposed. A significant outcome emerged in that 99.84% of DFBG in wastewater was removed using K-nZVI after reacting for 60 min.

  6. Synthesis of kaolin supported nanoscale zero-valent iron and its degradation mechanism of Direct Fast Black G in aqueous solution

    International Nuclear Information System (INIS)

    Jin, Xiaoying; Chen, Zhengxian; Zhou, Rongbing; Chen, Zuliang

    2015-01-01

    Graphical abstract: UV–visible spectra of DFBG solution using K-nZVI (1:1) nanoparticles. (a) Before reaction; (b) during reaction; (c) after reaction. - Highlights: • Kaolin-supported Fe 0 nanoparticle (K-nZVI) was synthesized. • Degradation of Direct Fast Black by K-nZVI was studied. • K-nZVI was characterized by SEM, XRD, UV and FIIR. • Degradation mechanism of Direct Fast Black was proposed. - Abstract: Calcinated kaolin supported nanoscale zero-valent iron (K-nZVI) was synthesized and used for the removal of tetrad azo-group dye-Direct Fast Black G (DFBG) from aqueous solution. The results demonstrated that after reacting for 10 min with an initial concentration of DFBG 100 mg L −1 (pH 9.49), 78.60% of DFBG was removed using K-nZVI, while only 41.39% and 12.56% of DFBG were removed using nZVI and kaolin, respectively. K-nZVI with a mass ratio of nZVI nanoparticles versus kaolin at 1:1 was found to have a high degree of reactivity. Furthermore, scanning electron microscopy (SEM) confirmed that nZVI was better dispersed when kaolin was present. XRD patterns indicated that iron oxides were formed after reaction. Fourier transforms infrared spectra (FTIR) and UV–visible demonstrated that the peak in the visible light region of DFBG was degraded and new bands were observed. Kinetics studies showed that the degradation of DFBG fitted well to the pseudo first-order model. The degradation of DFBG by K-nZVI was based on its adsorption onto kaolin and iron oxides, and subsequently reduction using nZVI was proposed. A significant outcome emerged in that 99.84% of DFBG in wastewater was removed using K-nZVI after reacting for 60 min

  7. Control of the Mexican bean weevil Zabrotes subfasciatus with kaolin Controle do caruncho-do-feijão Zabrotes subfasciatus com caulim

    Directory of Open Access Journals (Sweden)

    Adriana Yatie Mikami

    2010-07-01

    Full Text Available The Mexican bean weevil Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae is an important pest of stored beans in tropical regions. The efficiency of kaolin [with or without neem (Azadirachta indica oil] and diatomaceous earth (DE (standard treatment was studied in laboratory aiming to obtain alternatives for chemical control of this insect. Insects were confined in plastic vials containing beans treated with kaolin (2, 4 and 8g kg-1, kaolin + neem [2g kg-1(5% neem oil], diatomaceous earth (1g kg-1 and control. Mortality of adult insects, number of eggs and F1generation beetles emergency were assessed. Kaolin caused mortality of Z. subfasciatus, however higher periods and doses than DE were necessary to promote high mortality (100% or close. Kaolin treatments also affected female behavior because many eggs were placed in the vials walls. Number of emerged adults (F1 was similar between DE and kaolin; hence, kaolin constitutes a promising tool to the management of Z. subfasciatus. The mixture of kaolin and neem oil was not efficient in the control of Z. subfasciatus.O caruncho-do-feijão Zabrotes subfasciatus (Coleoptera: Chrysomelidae: Bruchinae é uma importante praga de grãos de feijão armazenado nas regiões tropicais. A eficiência do caulim [com ou sem óleo de nim (Azadirachta indica] e terra diatomácea (TD (tratamento padrão foi estudada em laboratório com o intuito de obter alternativas para o controle químico deste inseto. Insetos foram confinados em frascos de plástico com feijão tratado com caulim (2, 4 e 8g kg-1, caulim + nim [2g kg-1(5% óleo de nim], terra diatomácea (1g kg-1 e controle. Mortalidade de insetos adultos, número de ovos e emergência da geração F1 foram avaliados. Caulim causou a mortalidade de Z. subfasciatus, porém foram necessários maiores períodos e doses que a TD para promover elevada mortalidade (100% ou aproximadamente. Os tratamentos com caulim também afetaram o comportamento da f

  8. Simultaneous removal of organic contaminants and heavy metals from kaolin using an upward electrokinetic soil remediation process

    International Nuclear Information System (INIS)

    Wang, J.-Y.; Huang, X.-J.; Kao, Jimmy C.M.; Stabnikova, Olena

    2007-01-01

    Kaolins contaminated with heavy metals, Cu and Pb, and organic compounds, p-xylene and phenanthrene, were treated with an upward electrokinetic soil remediation (UESR) process. The effects of current density, cathode chamber flushing fluid, treatment duration, reactor size, and the type of contaminants under the vertical non-uniform electric field of UESR on the simultaneous removal of the heavy metals and organic contaminants were studied. The removal efficiencies of p-xylene and phenanthrene were higher in the experiments with cells of smaller diameter or larger height, and with distilled water flow in the cathode chamber. The removal efficiency of Cu and Pb were higher in the experiments with smaller diameter or shorter height cells and 0.01 M HNO 3 solution as cathode chamber flow. In spite of different conditions for removal of heavy metals and organics, it is possible to use the upward electrokinetic soil remediation process for their simultaneous removal. Thus, in the experiments with duration of 6 days removal efficiencies of phenanthrene, p-xylene, Cu and Pb were 67%, 93%, 62% and 35%, respectively. The experiment demonstrated the feasibility of simultaneous removal of organic contaminants and heavy metals from kaolin using the upward electrokinetic soil remediation process

  9. Short communication: Laboratory approach to the use of sulphur and kaolin as preventive control against Drosophila suzukii

    Energy Technology Data Exchange (ETDEWEB)

    Pérez-Guerrero, S.; Molina, J.M.

    2016-11-01

    Drosophila suzukii (Matsumura, 1931) is an invasive pest from South East Asia that was detected for the first time in Southern Europe in 2008. This species can damage a wide range of soft-skinned fruits crops affecting ripening fruits and causing important economic losses. Since the exclusive use of chemical insecticides for controlling D. suzukii may prompt the appearance of resistance and environmental pollution, alternative methods compatible with sustainable management are required. In this study, commercial formulations of powdered sulphur and kaolin were tested as a preventive method applied to blueberry fruits under laboratory conditions. In no-choice assay, powdered sulphur had a significant effect on oviposition and adult emergency with reductions of 76% and 77%, respectively. In addition, sulphur displayed a significant toxicity on males and lethal effect with over 40% adult mortality seven days after exposure. The choice assay confirmed and improved the powdered sulphur effects, with reductions of 98% and 96% in oviposition and adult emergence, respectively. In contrast, kaolin produced no significant reduction in infestation and adult mortality during no-choice and choice assays. These outcomes suggest that preventive use of powdered sulphur could be considered for sustainable control of D. suzukii in some berry crops. (Author)

  10. Immobilization of horseradish peroxidase onto kaolin by glutaraldehyde method and its application in decolorization of anthraquinone dye

    Directory of Open Access Journals (Sweden)

    Šekuljica Nataša Ž.

    2016-01-01

    Full Text Available The problem of environmental pollution day by day becomes more worrisome, primarily due to the large amounts of wastewater contaminated with various harmful organic compounds, discharged into the environment untreated or partially clean. Feasibility of use of horseradish peroxidase (Amoracia rusticana in the synthetic dyes decolorization was approved by many researchers. Among a number of supports used for the immobilization, it was found that natural clay, kaolin has excellent features which are a precondition for obtaining biocatalysts with the excellent performances. For this reason, a horseradish peroxidase was immobilized onto kaolin using glutaraldehyde as a cross-linking agent. Obtained biocatalyst was applied in the decolorization of anthraquinone dye C. I. Acid Violet 109. Under determined optimal conditions (pH 4.0, hydrogen peroxide concentration 0.6 mM, dye concentration 30 mg L-1, temperature 24ºC around 76 % of dye decolorization was achieved. Reusability study showed that resulting biocatalyst was possible to apply four times in the desired reaction with relatively high decolorization percentage. [Projekat Ministarstva nauke Republike Srbije, br. III-46010 i br. 172013

  11. Effect of Kaolin Clay and Alumina on Thermal Performance and Char Morphology of Intumescent fire retardant coating

    Directory of Open Access Journals (Sweden)

    aziz Hammad

    2014-07-01

    Full Text Available Intumescent fire retardant coating (IFRC have been developed by using ammonium polyphosphate, expandable graphite, melamine, boric acid, kaolin clay and alumina as fillers bound together with epoxy resin and cured with the help of curing agent. Five different formulations were developed with and without using fillers. Cured samples were burned in furnace at 500°C for 2h for char expansion. Bunsen burner test was performed for 1h using UL-94 vertical burning test to investigate the thermal performance of IFRC. The resultant char obtained after burning of coated samples were characterized by using field emission scanning electron microscopy for char morphology. Char composition was analyzed by using fourier transform infrared spectroscopy. Thermogravimetric analysis was carried out to investigate the residual weight of coating. Results showed that formulation with 0.5 weight % of kaolin clay and 0.5 weight % of alumina provide best thermal performance, uniform and multi-porous char structure with high anti-oxidation property.

  12. Facile Fabrication of a PDMS@Stearic Acid-Kaolin Coating on Lignocellulose Composites with Superhydrophobicity and Flame Retardancy

    Directory of Open Access Journals (Sweden)

    Zhe Wang

    2018-05-01

    Full Text Available The disadvantages such as swelling after absorbing water and flammability restrict the widespread applications of lignocellulose composites (LC. Herein, a facile and effective method to fabricate superhydrophobic surfaces with flame retardancy on LC has been investigated by coating polydimethylsiloxane (PDMS and stearic acid (STA modified kaolin (KL particles. The as-prepared coatings on the LC exhibited a good repellency to water (a contact angle = 156°. Owing to the excellent flame retardancy of kaolin particles, the LC coated with PDMS@STA-KL displayed a good flame retardancy during limiting oxygen index and cone calorimeter tests. After the coating treatment, the limiting oxygen index value of the LC increased to 41.0. Cone calorimetry results indicated that the ignition time of the LC coated with PDMS@STA-KL increased by 40 s compared with that of uncoated LC. Moreover, the peak heat release rate (PHRR and the total heat release (THR of LC coated with PDMS@STA-KL reduced by 18.7% and 19.2% compared with those of uncoated LC, respectively. This LC coating with improved water repellency and flame retardancy can be considered as a potential alternative to protect the lignocellulose composite.

  13. Short communication: Laboratory approach to the use of sulphur and kaolin as preventive control against Drosophila suzukii

    Directory of Open Access Journals (Sweden)

    Sergio Pérez-Guerrero

    2016-06-01

    Full Text Available Drosophila suzukii (Matsumura, 1931 is an invasive pest from South East Asia that was detected for the first time in Southern Europe in 2008. This species can damage a wide range of soft-skinned fruits crops affecting ripening fruits and causing important economic losses. Since the exclusive use of chemical insecticides for controlling D. suzukii may prompt the appearance of resistance and environmental pollution, alternative methods compatible with sustainable management are required. In this study, commercial formulations of powdered sulphur and kaolin were tested as a preventive method applied to blueberry fruits under laboratory conditions. In no-choice assay, powdered sulphur had a significant effect on oviposition and adult emergency with reductions of 76% and 77%, respectively. In addition, sulphur displayed a significant toxicity on males and lethal effect with over 40% adult mortality seven days after exposure. The choice assay confirmed and improved the powdered sulphur effects, with reductions of 98% and 96% in oviposition and adult emergence, respectively. In contrast, kaolin produced no significant reduction in infestation and adult mortality during no-choice and choice assays. These outcomes suggest that preventive use of powdered sulphur could be considered for sustainable control of D. suzukii in some berry crops.

  14. Comparative numerical study of kaolin clay with three drying methods: Convective, convective–microwave and convective infrared modes

    International Nuclear Information System (INIS)

    Hammouda, I.; Mihoubi, D.

    2014-01-01

    Highlights: • Modelling of drying of deformable media. • Theoretical study of kaolin clay with three drying methods: convective, convective–microwave and convective infrared mode. • The stresses generated during convective, microwave/convective drying and infrared/convective drying. • The combined drying decrease the intensity of stresses developed during drying. - Abstract: A mathematical model is developed to simulate the response of a kaolin clay sample when subjected to convective, convective–microwave and convective–infrared mode. This model is proposed to describe heat, mass, and momentum transfers applied to a viscoelastic medium described by a Maxwell model with two branches. The combined drying methods were investigated to examine whether these types of drying may minimize cracking that can be generated in the product and to know whether the best enhancement is developed by the use of infra-red or microwave radiation. The numerical code allowed us to determine, and thus, compare the effect of the drying mode on drying rate, temperature, moisture content and mechanical stress evolutions during drying. The numerical results show that the combined drying decrease the intensity of stresses developed during drying and that convective–microwave drying is the best method that gives a good quality of dried product

  15. Determination of iron and titanium in kaolins by the method of non-dispersive X-ray fluorescence

    International Nuclear Information System (INIS)

    Bialy, N.; Kierzek, J.; Parus, J.

    1976-01-01

    The possibility of application of the radioactive source excited X-ray fluorescence analysis for titanium and iron determination in kaolins to the routine test of the refinement process has been studied. The iron content can be determined with a simple counting system using a single-channel pulse height analyser, argon filled proportional counter and 109 Cd source of 3 mCi for the excitation of K Fe rays. The samples were analyzed both as pellets and powders. The iron content ranged from 0.2-2.5% and titanium from 0.1-0.64%. The best values of precision and determination limit have been achieved for iron with 238 Pu and for titanium with 55 Fe. The precision and accuracy of the X-ray fluorescence method of iron and titanium determination in kaolins are comparable to those of the chemical method. For the simultaneous iron and titanium determination in the discussed region of concentration it is the most advantageous to use the plutonium source with the activity of several tens of mCi and Si(Li) detector with a moderate resolution (250-300 eV for 5.9 keV). The time of the analysis carried out by the described method is several times shorter than the chemical method. The apparatus used in this method is relatively simple, the sample preparation does not require any chemical treatment and the cost of labour of the sample preparation is minimal. (T.G.)

  16. Application of kaolin-based catalysts in biodiesel production via transesterification of vegetable oils in excess methanol.

    Science.gov (United States)

    Dang, Tan Hiep; Chen, Bing-Hung; Lee, Duu-Jong

    2013-10-01

    Biodiesel production from transesterification of vegetable oils in excess methanol was performed by using as-prepared catalyst from low-cost kaolin clay. This effective heterogeneous catalyst was successfully prepared from natural kaolin firstly by dehydroxylation at 800°C for 10h and, subsequently, by NaOH-activation hydrothermally at 90°C for 24h and calcined again at 500°C for 6h. The as-obtained catalytic material was characterized with instruments, including FT-IR, XRD, SEM, and porosimeter (BET/BJH analysis). The as-prepared catalyst was advantageous not only for its easy preparation, but also for its cost-efficiency and superior catalysis in transesterification of vegetable oils in excess methanol to produce fatty acid methyl esters (FAMEs). Conversion efficiencies of soybean and palm oils to biodiesel over the as-prepared catalysts reached 97.0±3.0% and 95.4±3.7%, respectively, under optimal conditions. Activation energies of transesterification reactions of soybean and palm oils in excess methanol using these catalysts are 14.09 kJ/mol and 48.87 kJ/mol, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Bulk Fluidity and Apparent Wall Slip of Aqueous Kaolin Suspensions Studied Using the Cone-Cone (KK) Sensor: Effect of the Sensor Surface Quality.

    Czech Academy of Sciences Publication Activity Database

    Pěnkavová, Věra; Tihon, Jaroslav; Wein, Ondřej

    2017-01-01

    Roč. 533, NOV 20 (2017), s. 338-346 ISSN 0927-7757 EU Projects: Foundation for Science and Technology(XE) MP1305 Institutional support: RVO:67985858 Keywords : aqueous kaolin suspensions * rotational AWS viscometry * apparent wall slip Subject RIV: CI - Industrial Chemistry, Chemical Engineering OBOR OECD: Chemical process engineering Impact factor: 2.714, year: 2016

  18. High-temperature CO2 capture cycles of hydrated limestone prepared with aluminum (hydr)oxides derived from kaolin

    International Nuclear Information System (INIS)

    Wang, Ke; Zhao, Pengfei; Guo, Xin; Han, Dongtai; Chao, Yang

    2014-01-01

    Highlights: • Hydrated limestone exhibited a higher reactivity and stability. • Microstructure of hydrated limestone was significantly improved. • Hydrated limestone still suffered less loss-incapacity. • Hydrated limestone sorbents with kaolin-based binders were prepared and characterized. • Sorbents prepared from hydrated limestone and Al(OH) 3 binder are a promising sorbent. - Abstract: A simple and convenient process was used to improve the utilization of natural limestone and kaolin for calcium looping technology and environmental applications. The calcined natural limestone modified with the distilled water (denoted as Limestone-W), was systematically studied and compared with the other CaO sorbents (calcium acetate, calcium D-gluconate and calcined natural limestone). These CaO-based sorbents were tested for their CO 2 capture behavior through 20 carbonation/calcination cycles in a thermo-gravimetric analyzer (TGA). Their morphology, pore structure and phase composition before and after carbonation/calcination cycles were determined by scanning electron microscopy, nitrogen adsorption, and X-ray diffraction. The first-cycle and multicycle sorption results revealed that the Limestone-W sorbent exhibited a relatively faster reaction rate and higher cyclic CO 2 capture. The characterization data indicated that the Limestone-W was composed of a special calcium oxide structure with lower crystalline and higher porosity nanoparticles, which appeared to be the main reasons for its higher CO 2 capture capability. However, the Limestone-W still suffered loss of reactivity, even though it was less pronounced than the other CaO sorbent. To avoid this unfavorable effect, a thermally stable inert material (aluminum hydroxide derived from kaolin) was incorporated into the Limestone-W structure. This new sorbent revealed higher stability because the formation of a stable framework of Ca 12 Al 14 O 33 particles hindered densification and sintering of the CaO phase

  19. Síntese e caracterização de hidrogéis compósitos a partir de copolímeros acrilamida-acrilato e caulim: efeito da constituição de diferentes caulins do nordeste brasileiro Synthesis and characterization of poly (acrylamide-co-acrylate and kaolin hydrogel composites: effect of the constitution of different kaolins from northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Carlos W. de Q. Brito

    2013-01-01

    Full Text Available Superabsorbent hydrogels based on poly (acrylamide-co-acrylate and different kaolins, were prepared by free-radical aqueous copolymerization. FTIR and WAXS techniques were employed for characterization of a series of hydrogels, obtained by varying the percentage of clay, crosslinking and constitution of kaolin. The water absorbency at equilibrium (Weq decreased with increasing clay content and the amount of crosslinking agent. Superabsorbent hydrogel (Weq > 1084 g H2O/g gel was obtained as 10 wt% of white kaolin and 0.05 mol% of crosslinking agent were used. The hydrogel proved sensitive to pH variation and the presence of salts.

  20. Fabrication of recyclable and durable superhydrophobic materials with wear/corrosion-resistance properties from kaolin and polyvinylchloride

    Science.gov (United States)

    Qu, Mengnan; Liu, Shanshan; He, Jinmei; Feng, Juan; Yao, Yali; Ma, Xuerui; Hou, Lingang; Liu, Xiangrong

    2017-07-01

    In this study, mechanically stable and recyclable superhydrophobic materials were prepared from polyvinylchloride (PVC) and kaolin nanoparticles modified by stearic acid using a simple and low-cost drop-coating. The obtained materials displayed liquid-repellent toward water and several other liquids of daily life (such as orange juice, coffee, milk, coca cola and ink). These superhydrophobic materials showed remarkable robustness against sandpaper abrasion, UV-irradiation and ultrasonication test, while retaining its superhydrophobicity even after 60 abrasion cycles loaded of 500 g with sandpaper, 7 days UV-irradiation or 120 min ultrasonication test. The excellent durability against complex conditions was attributed to the hierarchical structure and strong interfacial adhesion of the materials. More significantly, the materials used in the coating could be recycled and reconstructed without losing its superhydrophobicity. The current superhydrophobic materials tolerate rigorous environment, opening a new avenue to a variety of practical applications.

  1. Infrared Spectroscopic Study on Structural Change and Interfacial Interaction in Rubber Composites Filled with Silica-Kaolin Hybrid Fillers

    Science.gov (United States)

    Chen, Y.; Guan, J.; Hu, H.; Gao, H.; Zhang, L.

    2016-07-01

    A series of natural rubber/styrene butadiene rubber/polybutadiene rubber composites was prepared with nanometer silica and micron kaolin by a dry modification process, mechanical compounding, and mold vulcanization. Fourier transform infrared spectroscopy and a scanning electron microscope were used to investigate the structural changes and interfacial interactions in composites. The results showed that the "seesaw" structure was formed particularly with the incorporation of silica particles in the preparation process, which would be beneficial to the dispersibility of fillers in the rubber matrix. The kaolinite platelets were generally arranged in directional alignment. Kaolinite with smaller particle size and low-defect structure was more stable in preparation, but kaolinite with larger particle size and high defect structure tended to change the crystal structure. The composite prepared in this research exhibited excellent mechanical and thermal properties.

  2. Study on the NaOH/metakaolin ratio and crystallization time for zeolite a synthesis from kaolin using statistical design

    Energy Technology Data Exchange (ETDEWEB)

    Silva Filho, Severino Higino da; Bieseki, Lindiane; Pergher, Sibele Berenice Castella, E-mail: sibelepergher@gmail.com [Universidade Federal do Rio Grande do Norte (LABPEMOL/UFRN), Natal, RN (Brazil). Lab. de Peneiras Moleculares; Maia, Ana Aurea B.; Angelica, Romulo Simoes [Universidade Federal do Para (UFPA), Belem PA (Brazil); Treichel, Helen [Universidade Federal da Fronteira Sil (UFFS), Erechim, RS (Brazil)

    2017-05-15

    The NaOH/metakaolin ratio and crystallization time were studied for the synthesis of zeolite NaA from a sample of kaolin from a Capim mine. The tests were carried out by using statistical design with axial points and replication of the central point. The samples obtained were characterized by X-ray diffraction (DRX), scanning electron microscopy and chemical analysis using a microprobe EPMA. The results showed that there is a relationship between the amount of NaOH added and crystallization time. The tests carried out using the lowest NaOH/metakaolin ratio (0.5) and the shortest time (4 h) produced a non-crystalline material. On the other hand, increasing the NaOH/metakaolin ratio and the crystallization time led to the formation of a NaA phase with a high structural level, but with the presence of a sodalite phase as an impurity. (author)

  3. Synthesis of Al4SiC4 powders from kaolin grog, aluminum and carbon black by carbothermal reaction

    Science.gov (United States)

    Yuan, Wenjie; Yu, Chao; Deng, Chengji; Zhu, Hongxi

    2013-12-01

    In this paper, the synthesis of Al4SiC4 used as natural oxide materials by carbothermal reduction was investigated in order to explore the synthesis route with low costs. The samples were calcined by using kaolin grog, aluminum and carbon black as raw materials with the selected proportion at the temperature from 1500 to 1800 ° C for 2 hours under flow argon atmosphere. The phase composition of reaction products were determined by X-ray diffraction. The microstructure and elemental composition of different phases were observed and identified by scanning electron microscopy and energy dispersive spectroscopy. The mechanism of reaction processing was discussed. The results show that Al4SiC4 powders composed of hexagonal plate-like particulates with various sizes and the thickness of less than 20 μm are obtained when the temperature reaches 1800 °C.

  4. Synthesis of Al4SiC4 powders from kaolin grog, aluminum and carbon black by carbothermal reaction

    International Nuclear Information System (INIS)

    Yuan, Wenjie; Yu, Chao; Deng, Chengji; Zhu, Hongxi

    2013-01-01

    In this paper, the synthesis of Al 4 SiC 4 used as natural oxide materials by carbothermal reduction was investigated in order to explore the synthesis route with low costs. The samples were calcined by using kaolin grog, aluminum and carbon black as raw materials with the selected proportion at the temperature from 1500 to 1800 ° C for 2 hours under flow argon atmosphere. The phase composition of reaction products were determined by X-ray diffraction. The microstructure and elemental composition of different phases were observed and identified by scanning electron microscopy and energy dispersive spectroscopy. The mechanism of reaction processing was discussed. The results show that Al 4 SiC 4 powders composed of hexagonal plate-like particulates with various sizes and the thickness of less than 20 μm are obtained when the temperature reaches 1800 °C

  5. Crystallite size distribution of clay minerals from selected Serbian clay deposits

    Directory of Open Access Journals (Sweden)

    Simić Vladimir

    2006-01-01

    Full Text Available The BWA (Bertaut-Warren-Averbach technique for the measurement of the mean crystallite thickness and thickness distributions of phyllosilicates was applied to a set of kaolin and bentonite minerals. Six samples of kaolinitic clays, one sample of halloysite, and five bentonite samples from selected Serbian deposits were analyzed. These clays are of sedimentary volcano-sedimentary (diagenetic, and hydrothermal origin. Two different types of shape of thickness distribution were found - lognormal, typical for bentonite and halloysite, and polymodal, typical for kaolinite. The mean crystallite thickness (T BWA seams to be influenced by the genetic type of the clay sample.

  6. Radiation-induced defects in clay minerals, markers of the mobility of the uranium in solution in the unconformity-type uranium deposits

    International Nuclear Information System (INIS)

    Morichon, E.

    2008-10-01

    This study presents the works driven on three groups of clay minerals (kaolins, illite, sudoite (di-tri-octahedral chlorites)) characteristics of the alteration halos surrounding unconformity-type uranium deposits, in order to reveal uranium paleo-circulations in the intra-cratonic meso-Proterozoic basins (1,2 - 1,6 Ga). Thanks to Electron Paramagnetic Resonance Spectroscopy (EPR), we were able to highlight the persistence of structural defects in kaolin-group minerals contemporaneous of the basin diagenesis, and demonstrate the existence of relatively stable defects in illites and sudoites contemporaneous of the uranium deposits setting. Thus, the main defect in illite (Ai centre) and the main defect in sudoite (As centre) are characterized by their g components such as, respectively, gt = 2,003 et g// = 2,051 for illite and gt = 2,008 et g// = 2,051 for sudoite. As the main defect in kaolins (kaolinite/dickite), the main defects in illite and sudoite are perpendicularly oriented according to the (ab) plane, on the tetrahedral Si-O bound. However, their thermal stabilities seem different. The observation of samples from different zones (background, anomal or mineralized) of the Athabasca basin (Canada) allowed to identify a parallel evolution between actual defects concentration measured in the different clay minerals and the proximity of the mineralisation zones. Consequently, clays minerals can be considered as potential plotters of zones where uranium-rich solutions have circulated. (author)

  7. Tsunami deposits

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    The NSC (the Nuclear Safety Commission of Japan) demand to survey on tsunami deposits by use of various technical methods (Dec. 2011), because tsunami deposits have useful information on tsunami activity, tsunami source etc. However, there are no guidelines on tsunami deposit survey in JAPAN. In order to prepare the guideline of tsunami deposits survey and evaluation and to develop the method of tsunami source estimation on the basis of tsunami deposits, JNES carried out the following issues; (1) organizing information of paleoseismological record and tsunami deposit by literature research, (2) field survey on tsunami deposit, and (3) designing the analysis code of sediment transport due to tsunami. As to (1), we organize the information gained about tsunami deposits in the database. As to (2), we consolidate methods for surveying and identifying tsunami deposits in the lake based on results of the field survey in Fukui Pref., carried out by JNES. In addition, as to (3), we design the experimental instrument for hydraulic experiment on sediment transport and sedimentation due to tsunamis. These results are reflected in the guideline on the tsunami deposits survey and evaluation. (author)

  8. Tsunami deposits

    International Nuclear Information System (INIS)

    2013-01-01

    The NSC (the Nuclear Safety Commission of Japan) demand to survey on tsunami deposits by use of various technical methods (Dec. 2011), because tsunami deposits have useful information on tsunami activity, tsunami source etc. However, there are no guidelines on tsunami deposit survey in JAPAN. In order to prepare the guideline of tsunami deposits survey and evaluation and to develop the method of tsunami source estimation on the basis of tsunami deposits, JNES carried out the following issues; (1) organizing information of paleoseismological record and tsunami deposit by literature research, (2) field survey on tsunami deposit, and (3) designing the analysis code of sediment transport due to tsunami. As to (1), we organize the information gained about tsunami deposits in the database. As to (2), we consolidate methods for surveying and identifying tsunami deposits in the lake based on results of the field survey in Fukui Pref., carried out by JNES. In addition, as to (3), we design the experimental instrument for hydraulic experiment on sediment transport and sedimentation due to tsunamis. These results are reflected in the guideline on the tsunami deposits survey and evaluation. (author)

  9. Gamma-induced radiation polymerization of kaolin composite for sorption of lanthanum, europium and uranium ions from low-grade monazite leachate

    International Nuclear Information System (INIS)

    Metwally, S.S.; Hassan, R.S.; El-Masry, E.H.; Borai, E.H.

    2018-01-01

    Gamma radiation polymerization method was used for the modification of kaolin to produce (poly acrylamide-acrylic acid)-Kaolin (PAM-AA-K). Monazite ore is one of the main resources of uranium and lanthanide elements, therefore, this work focused on sorption of uranium, lanthanum and europium ions from low grade monazite leachate. The removal percent for Eu 3+ , La 3+ and UO 2 2+ are 94.6, 91.6 and 73.4%, respectively. Monolayer capacity of Eu 3+ , La 3+ and UO 2 2+ were found to be 54.64, 45.87 and 37.59 mg/g, respectively. The sorption mechanism of lanthanum and europium ions on PAM-AA-K composite mainly takes place as Ln(OH) 2+ , and for uranium as uranyl ion, UO 2 2+ . (author)

  10. Characterization of ceramic masses using raw material of Para, Brazil: kaolin in natura; Caracterizaco de massas ceramicas utilizando materia--prima do Para: caulim in natura

    Energy Technology Data Exchange (ETDEWEB)

    Vida, T.A.; Facury Neto, E.; Rabelo, A.A. [Universidade Federal do Para (UFPA), Maraba, PA (Brazil). Fac. de Engenharia de Materiais

    2009-07-01

    The incorporation rejects to the mixtures has if shown viable in the reduction of the environmental liability and for the obtaining of a better quality of the ceramic mass. In the present work, is tried to study the potentiality of the use of ceramic formulations with the addition of kaolin in natura to the clays. Formulations with two clays of the area of the municipal district of Maraba with addition of up to 60% in kaolin weight were prepared and characterized. For the determination of the physical and mechanical properties proof bodies were made by prensagem uniaxial and later burned in temperature from 900 to 1200 deg C with landing of 3 hours. The raw materials were characterized through diffraction of rays X (DRX) and thermogravimetric analysis. The proof bodies prepared were used for determination of the lineal retraction (RL), absorption of water, apparent porosity, apparent density, loss to the fire and rupture module the flexing. The results were satisfactory for the smallest kaolin tenors in the ceramic mass, and the mass with 20% presented rupture module elevated, in the temperature of 1200 deg C. (author)

  11. Zeolite A synthesized from wastes of kaolin improvement process; Zeolita A sintetizada a partir de rejeitos do processo de beneficiamento de caulim

    Energy Technology Data Exchange (ETDEWEB)

    Santana, D.L.; Neves, R.F.; Silva, D.L., E-mail: danielaliraeq@yahoo.com.br, E-mail: dasilva@ufpa.br [Programa de Pos-Graduacao em Engenharia Quimica, Universidade Federal do Para - UFPA, Belem, PA (Brazil); Saraiva, A.C.F. [Centro de Tecnologia da Eletronorte, Belem, PA (Brazil)

    2012-04-15

    Raw materials were used to synthesize zeolite A as an alternative and more economical source of silica and aluminum, using waste from the kaolin of the paper industry. Zeolites are crystalline substances with a structure characterized by a framework of linked tetrahedra, each one consisting of four oxygen atoms surrounding a cation. The development of processes for the synthesis of zeolites is of great interest for use in the areas of purification, adsorption and catalysis. The starting materials for the synthesis of zeolite A consisted of wastes from kaolin beneficiation of paper companies of Para state, Brazil. The zeolite was obtained after calcination at 85 and 110 deg C during 24 h. The characterization of the starting material was performed by X-ray diffraction, chemical analysis, thermogravimetric and differential thermal analysis, and scanning electron microscopy. The characterization of zeolite A was done by X-ray diffraction and scanning electron microscopy. The kaolin waste used as starting material showed to be essentially kaolinite mineral. For the temperatures and time used in the synthesis it was possible to form the crystalline phase of zeolite A for the two starting materials. (author)

  12. Exogenous deposits

    International Nuclear Information System (INIS)

    Khasanov, A.Kh.

    1988-01-01

    Exogenous deposits forming as a result of complex exogenous processes, passed under the influence of outside forces on the Earth surface. To them relate physical and chemical weathering, decomposition and decay of mineral masses, redistribution and transportation of material, forming and deposit of new minerals and ores steady on the earth surface conditions

  13. Partitioning of hexachlorobenzene in a kaolin/humic acid/surfactant/water system: Combined effect of surfactant and soil organic matter

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Jinzhong; Wang, Lingling [Environmental Science Research Institute, Huazhong University of Science and Technology, Wuhan 430074 (China); Lu, Xiaohua, E-mail: hust-esri2009@hotmail.com [Environmental Science Research Institute, Huazhong University of Science and Technology, Wuhan 430074 (China); Lin, Yusuo; Zhang, Shengtian [Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China, Nanjing 210042 (China)

    2011-11-30

    Highlights: Black-Right-Pointing-Pointer We study HCB partitioning in a kaolin/humic acid/TX100/water system. Black-Right-Pointing-Pointer We reveal influence of TX100-HA interaction on TX100 and HA sorption to kaolin. Black-Right-Pointing-Pointer We verify combined effect of TX100 and HA on HCB desorption from clay. - Abstract: Understanding the combined effect of soil organic matter (SOM) and surfactants on the partitioning of hydrophobic organic compounds in soil/water systems is important to predict the effectiveness of surfactant-enhanced remediation (SER). In the present study we investigate the partitioning of hexachlorobenzene (HCB) within a humic acid (HA)-coated kaolin/Triton X-100 (TX100)/water system, with special emphasis on the interaction between TX100 and HA, and their combined effect on HCB sorption. HA firstly enhanced then suppressed TX100 sorption to kaolin as the amounts of HA increased, while the addition of TX100 led to a consistent reduction in HA sorption. In the HA-coated kaolin/TX100/water system, TX100 played a primary role in enhancing desorption of HCB, while the role could be suppressed and then enhanced as HA coating amounts increased. Only at HA coating above 2.4%, dissolved HA outcompeted clay-bound HA for HCB partitioning, resulting in dissolved HA enhanced desorption. The presence of dissolved HA at these conditions further promoted the effectiveness of TX100 enhanced desorption. Despite a reduced TX100 sorption to clay was achieved due to the presence of dissolved HA, the effect on HCB desorption was comparatively slight. A reliable cumulative influence of HA and TX100 on HCB desorption was observed, although HCB desorption by HA/TX100 mixed was less than the sum of HA and TX100 individually. Our study suggests that for soils of high organic contents, the combined effect of SOM and surfactants on HOCs desorption can be applied to improve the performance of SER.

  14. Uranium deposits associated to tertiary acid volcanism of the Pena Blanca Sierra (Chihuahua, Mexico)

    International Nuclear Information System (INIS)

    Aniel, B.

    1986-12-01

    The uraniferous deposits located in the Sierra de Pena Blanca (Chihuahua, Mexico) are the consequence of successive events that modified acid volcanic rocks. The devitrification of the Nopal Formation, vitroclastic tuffs, is esential in the cooling history because it releases uranium that becomes available. The uranium present in fluids as uranylcarbonate complexes, precipitate along the lamellea of hematite (exsolutions of the ilmenites). The presence of sulfur causes the destabilization of the ilmenites with uranium oxide (pitchblende - titanium oxide - pyrite), the pseudomorph of magnetites (pitchblende - pyrite) and the transformation of hematite into pyrite. The silice coming from the kaolinization of feldspars recristallizes as microcristalline quartz so that the rock appears compact. Fractures cause the uplifting of the lower unit of Nopal formation. It has been altered to montmorillonite. A carbonatation of this tuff has been observed and these two types of alteration occur after kaolinization. The Escuadra formation overlies the Nopal formation. The deposition takes place on an eroded basement where a soil developed. The two formations will together undergo transformations due to the saturation level and the primary ore will be only oxidized or oxidized, transported and reconcentrated. Late and localized thermal activities have been observed and may be the result of tectonic movements occurring after the supergene modification [fr

  15. Coagulation performance of a novel poly-ferric-acetate (PFC) coagulant in phosphate-kaolin synthetic water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Yanxin; Lu, Jinpeng; Dong, Xiongzi; Yao, Chengli [Hefei Normal University, Hefei (China); Hao, Jianwen [Anhui Vocational and Technical College, Hefei (China)

    2017-10-15

    The process of coagulation-flocculation is increasingly applied in wastewater treatment. And the polymerized inorganic coagulants are widely used among these coagulation-flocculation processes. However, conventional coagulants using sulfates or chlorides as counter anion may give rise to corrosion. The purpose of this study was to synthesize PFC coagulants in which acetate is used as counter anion. The influences on the preparation of PFC were optimized. The synthesis was done at the optimum conditions, such as temperature of 60 .deg. C, the Fe/CH{sub 3}COOH molar ratio of 1 : 4.0 and reaction time of 6 h, respectively. The prepared PFC coagulants were characterized by Fourier transform infrared (FTIR) spectrophotometry and scanning electron microscopy (SEM). PFC was found to mainly form complexation polymeric species and present more cluster and lamellar structure. A series of jar tests were carried out to study the coagulation performance of PFC and PFS in phosphate-kaolin synthetic water treatment. Results showed that the coagulation performance of PFC was more efficient than PFS's in terms of the phosphorus removal efficiency and the residual turbidity. Due to using acetate as counter anion to iron, PFC is less harmful to the processes of water treatment and equipment than that of the conventional coagulants applied chlorides or sulfates. Therefore, PFC is a promising coagulant in the process of corrosion sensitive applications and the process of wastewater containing phosphorus treatment.

  16. Fabrication of recyclable and durable superhydrophobic materials with wear/corrosion-resistance properties from kaolin and polyvinylchloride

    International Nuclear Information System (INIS)

    Qu, Mengnan; Liu, Shanshan; He, Jinmei; Feng, Juan; Yao, Yali; Ma, Xuerui; Hou, Lingang; Liu, Xiangrong

    2017-01-01

    Highlights: • The scraped debris can be recycled and easily reused to fabricate the superhydrophobic materials. • The obtained materials displayed liquid-repellent toward water and several other liquids of daily life. • The superhydrophobic materials can retain excellent chemical stability and mechanical durability after rigorous tests. • This as-prepared material can be regarded as a real superhydrophobic “material”, not just the superhydrophobic “surface”. - Abstract: In this study, mechanically stable and recyclable superhydrophobic materials were prepared from polyvinylchloride (PVC) and kaolin nanoparticles modified by stearic acid using a simple and low-cost drop-coating. The obtained materials displayed liquid-repellent toward water and several other liquids of daily life (such as orange juice, coffee, milk, coca cola and ink). These superhydrophobic materials showed remarkable robustness against sandpaper abrasion, UV-irradiation and ultrasonication test, while retaining its superhydrophobicity even after 60 abrasion cycles loaded of 500 g with sandpaper, 7 days UV-irradiation or 120 min ultrasonication test. The excellent durability against complex conditions was attributed to the hierarchical structure and strong interfacial adhesion of the materials. More significantly, the materials used in the coating could be recycled and reconstructed without losing its superhydrophobicity. The current superhydrophobic materials tolerate rigorous environment, opening a new avenue to a variety of practical applications.

  17. Applicability of alkali activated slag-seeded Egyptian Sinai kaolin for the immobilization of 60Co radionuclide

    International Nuclear Information System (INIS)

    El-Naggar, M.R.

    2014-01-01

    The present work was established to determine the applicability of local Egyptian kaolinite and blast furnace slag (BFS) as raw materials toward the synthesis of geopolymers and subsequent immobilization of cobalt-60, which is one of the most abundant radionuclides generated in radioactive waste streams in Egypt. XRF, XRD, FT-IR, and SEM techniques were used to characterize the local raw materials and their corresponding alkali activated products. Metakaolin (MK) was obtained by thermal treatment of Egyptian Sinai kaolin 750 °C/4 h. MK and five different BFS content (5, 10, 30, 50 and 80%) were used to synthesize geopolymeric matrices using an alkaline activator of Si-modulus = 1.35 at solid/liquid ratios of 0.8. Compressive strength tests were performed indicating that 50% BFS addition gave the highest values of compressive strength. The IAEA standard leaching tests of cobalt-60 from the solidified waste matrices were carried out. The effective diffusion coefficients of cobalt-60 radionuclides from the solidified waste matrices were calculated to be in the order of 10 −14 cm 2 /s. Leaching of radionuclides was examined to be controlled by the wash-off mechanism with very acceptable values. These results gave encouragement that the tested Egyptian raw materials can be conveniently applied for the synthesis of geopolymers that can be used as a low-cost and high-efficiency materials for the immobilization of radioactive waste

  18. Effect of kaolin silver complex on the control of populations of Brettanomyces and acetic acid bacteria in wine.

    Science.gov (United States)

    Izquierdo-Cañas, P M; López-Martín, R; García-Romero, E; González-Arenzana, L; Mínguez-Sanz, S; Chatonnet, P; Palacios-García, A; Puig-Pujol, A

    2018-05-01

    In this work, the effects of kaolin silver complex (KAgC) have been evaluated to replace the use of SO 2 for the control of spoilage microorganisms in the winemaking process. The results showed that KAgC at a dose of 1 g/L provided effective control against the development of B. bruxellensis and acetic acid bacteria. In wines artificially contaminated with an initial population of B. bruxellensis at 10 4 CFU/mL, a concentration proven to produce off flavors in wine, only residual populations of the contaminating yeast remained after 24 days of contact with the additive. Populations of acetic bacteria inoculated into wine at concentrations of 10 2 and 10 4  CFU/mL were reduced to negligible levels after 72 h of treatment with KAgC. The antimicrobial effect of KAgC against B. bruxellensis and acetic bacteria was also demonstrated in a wine naturally contaminated by these microorganisms, decreasing their population in a similar way to a chitosan treatment. Related to this effect, wines with KAgC showed lower concentrations of acetic acid and 4-ethyl phenol than wines without KAgC. The silver concentration from KAgC that remained in the finished wines was below the legal limits. These results demonstrated the effectiveness of KAgC to reduce spoilage microorganisms in winemaking.

  19. Analysis and optimization of flocculation activity and turbidity reduction in kaolin suspension using pectin as a biopolymer flocculant.

    Science.gov (United States)

    Ho, Y C; Norli, I; Alkarkhi, Abbas F M; Morad, N

    2009-01-01

    The performance of pectin in turbidity reduction and the optimum condition were determined using Response Surface Methodology (RSM). The effect of pH, cation's concentration, and pectin's dosage on flocculating activity and turbidity reduction was investigated at three levels and optimized by using Box-Behnken Design (BBD). Coagulation and flocculation process were assessed with a standard jar test procedure with rapid and slow mixing of a kaolin suspension (aluminium silicate), at 150 rpm and 30 rpm, respectively, in which a cation e.g. Al(3+), acts as coagulant, and pectin acts as the flocculant. In this research, all factors exhibited significant effect on flocculating activity and turbidity reduction. The experimental data and model predictions well agreed. From the 3D response surface graph, maximum flocculating activity and turbidity reduction are in the region of pH greater than 3, cation concentration greater than 0.5 mM, and pectin dosage greater than 20 mg/L, using synthetic turbid wastewater within the range. The flocculating activity for pectin and turbidity reduction in wastewater is at 99%.

  20. Synthesis of mullite (3Al2O32SiO2) from local kaolin for radiation shielding

    Science.gov (United States)

    Ripin, Azuhar; Mohamed, Faizal; Aman, Asyraf

    2018-04-01

    Raw kaolin from Kota Tinggi, Johor was used in this study to produce ceramic mullite (3Al2O22SiO2) for radiation shielding materials. In this work, an attempt was made to study the potential of local minerals to be used as a shielding barrier for diagnostic radiology radiation facilities in hospitals and medical centers throughout Malaysia. The conventional ceramic processing route was employed in the study using different pressing strength and sintering time. The obtained samples were characterized using X-ray diffractometer (XRD) for phase identification of each of the samples. The lead equivalent (LE) test was carried out using 15.05 mCi Cobalt-57 with gamma energy of 122 keV to compute the abilities of the mullite ceramic samples to attenuate the radiation. XRD patterns of prepared ceramics revealed the presence of orthorhombic mullite, hexagonal quartz and orthorhombic sillimanite structures. Furthermore, the radiation test displayed the ability of ceramics to shield of 70 % of gamma radiation at the distance of 60 cm from the radiation source. The highest lead equivalent thickness is 1.0 mm Pb and the lowest is about 0.06 mm Pb. From the result, it is shown that the ceramic has the potential to use as a shielding barrier in diagnostic radiology facilities due to the ability of reducing the radiation dose up to 70 % from its initial value.

  1. The effects of sucralfate suspension and diphenhydramine syrup plus kaolin-pectin on radiotherapy-induced mucositis

    International Nuclear Information System (INIS)

    Barker, G.; Loftus, L.; Cuddy, P.; Barker, B.

    1991-01-01

    A prospective, double-blind study compared the effectiveness of sucralfate suspension with diphenhydramine syrup plus kaolin-pectin in reducing severity and pain of radiation-induced oropharyngeal mucositis. Fourteen patients who received at least 4600 cGy to the oral cavity used one of the mouth rinses four times a day, beginning at 1600 cGy. Data were collected on daily perceived pain and helpfulness of mouth rinse, weekly mucositis grade, weight change, and interruption of therapy. Analysis of data revealed no statistically significant differences between the two groups in any parameter. A retrospective review of 15 patients who had received at least 4600 cGy radiation to the oropharynx but had not used a daily mouth-coating rinse, was compared with the study group. Comparison of the two groups suggested that consistent daily oral hygiene and use of a mouth-coating agent will result in less pain and may reduce weight loss and interruption of radiation because of severe mucositis

  2. Synthesis of Nano- alumina Powder from Impure Kaolin and its Application for Arsenite Removal from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Ahmad Khodadadi Darban

    2013-07-01

    Full Text Available Adsorption is considered a cost-effective procedure, safer to handle with high removal efficiency. Activated alumina is the most commonly used adsorbent for the removal of arsenic from aqueous solutions. However, activated alumina has a low adsorption capacity and acts kinetically in a slow manner. An ideal adsorbent should have a high surface area, physical and/or chemical stability and be inexpensive. To meet this requirement, nanomeso porous γ-alumina with a high surface area (201.53 m2/g and small particle size (22–36 nm was prepared from inexpensive kaolin as the raw material, by precipitation method. The research results showed that adsorbent has the high adsorption capacity (for initial arsenite concentration up to 10 mg/L, in which 97.65% recovery was achieved. Optimal experimental conditions including pH, initial arsenite concentration and contact time were determined. Langmuir, Freundlich and Dubinin– Radushkevich isotherm models were applied to analyze the experimental data. The best interpretation for the experimental data was given by Langmuir adsorption isotherm equation and the maximum arsenite adsorbed by synthesized nano γ–alumina (qe was found to be 40 (mg/g.

  3. The effects of sucralfate suspension and diphenhydramine syrup plus kaolin-pectin on radiotherapy-induced mucositis

    Energy Technology Data Exchange (ETDEWEB)

    Barker, G.; Loftus, L.; Cuddy, P.; Barker, B. (Univ. of Missouri, Kansas City (USA))

    1991-03-01

    A prospective, double-blind study compared the effectiveness of sucralfate suspension with diphenhydramine syrup plus kaolin-pectin in reducing severity and pain of radiation-induced oropharyngeal mucositis. Fourteen patients who received at least 4600 cGy to the oral cavity used one of the mouth rinses four times a day, beginning at 1600 cGy. Data were collected on daily perceived pain and helpfulness of mouth rinse, weekly mucositis grade, weight change, and interruption of therapy. Analysis of data revealed no statistically significant differences between the two groups in any parameter. A retrospective review of 15 patients who had received at least 4600 cGy radiation to the oropharynx but had not used a daily mouth-coating rinse, was compared with the study group. Comparison of the two groups suggested that consistent daily oral hygiene and use of a mouth-coating agent will result in less pain and may reduce weight loss and interruption of radiation because of severe mucositis.

  4. Fabrication of recyclable and durable superhydrophobic materials with wear/corrosion-resistance properties from kaolin and polyvinylchloride

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Mengnan, E-mail: mnanqu@gmail.com; Liu, Shanshan; He, Jinmei, E-mail: jinmhe@gmail.com; Feng, Juan; Yao, Yali; Ma, Xuerui; Hou, Lingang; Liu, Xiangrong

    2017-07-15

    Highlights: • The scraped debris can be recycled and easily reused to fabricate the superhydrophobic materials. • The obtained materials displayed liquid-repellent toward water and several other liquids of daily life. • The superhydrophobic materials can retain excellent chemical stability and mechanical durability after rigorous tests. • This as-prepared material can be regarded as a real superhydrophobic “material”, not just the superhydrophobic “surface”. - Abstract: In this study, mechanically stable and recyclable superhydrophobic materials were prepared from polyvinylchloride (PVC) and kaolin nanoparticles modified by stearic acid using a simple and low-cost drop-coating. The obtained materials displayed liquid-repellent toward water and several other liquids of daily life (such as orange juice, coffee, milk, coca cola and ink). These superhydrophobic materials showed remarkable robustness against sandpaper abrasion, UV-irradiation and ultrasonication test, while retaining its superhydrophobicity even after 60 abrasion cycles loaded of 500 g with sandpaper, 7 days UV-irradiation or 120 min ultrasonication test. The excellent durability against complex conditions was attributed to the hierarchical structure and strong interfacial adhesion of the materials. More significantly, the materials used in the coating could be recycled and reconstructed without losing its superhydrophobicity. The current superhydrophobic materials tolerate rigorous environment, opening a new avenue to a variety of practical applications.

  5. Investigating the Influence of the Cerium loading in prepared Y zeolite from Iraqi kaolin on its Catalytic Performance

    Directory of Open Access Journals (Sweden)

    Karim Khalifa Esgair

    2018-01-01

    Full Text Available In this study, the effects of different loading doses of cerium in the prepared NaY zeolite from Iraqi kaolin were investigated. Al-Duara refinery atmospheric residue fluid catalytic cracking was selected as palpation reaction for testing the catalytic activity of cerium loading NaY zeolite. The insertion of cerium in NaY zeolites has been synthesized by simple ion exchange methods. Three samples of modified zeolite Y have been obtained by replacing the sodium ions in the original sample with cerium and the weight percent added are 0.35, 0.64, and 1.06 respectively. The effects of cerium loading to zeolite Y in different weight percent on the cracking catalysts were studied by employing a laboratory fluidized bed reactor. The experiments have been performed with weight hourly space velocity (WHSV range from 6 to 24 h-1, and the temperature range from 450 to 510 oC. The activity of the catalyst with 1.06 wt% cerium has been shown to be much greater than that of the sample parent NaY. Also it was observed that the addition of the cerium causes an increase in the thermal stability of the zeolite.

  6. Phase modification and dielectric properties of a cullet-paper ash-kaolin clay-based ceramic

    Science.gov (United States)

    Samah, K. A.; Sahar, M. R.; Yusop, M.; Omar, M. F.

    2018-03-01

    Novel ceramics from waste material made of ( x) paper ash-(80 - x) cullet-20 kaolin clay (10wt% ≤ x ≤ 30wt%) were successfully synthesized using a conventional solid-state reaction technique. Energy-dispersive X-ray analysis confirmed the presence of Si, Ca, Al, and Fe in the waste material for preparing these ceramics. The influence of the cullet content on the phase structures and the dielectric properties of these ceramics were systematically investigated. The impedance spectra were verified in the range from 1 Hz to 10 MHz at room temperature. The phase of the ceramics was found to primarily consist of wollastonite (CaSiO3), along with minor phases of γ-dicalcium silicate (Ca2SiO4) and quartz (SiO2). The sample with a cullet content of 55wt% possessed the optimum wollastonite structure and exhibited good dielectric properties. An increase of the cullet content beyond 55wt% resulted in a structural change from wollastonite to dicalcium silicate, a decrease in dielectric constant, and an increase in dielectric loss. All experimental results suggested that these novel ceramics from waste are applicable for electronic devices.

  7. Incorporation of feasibility study of residue thin kaolin in of porcelain formulations production; Estudo da viabilidade da incorporacao do residuo fino do caulim na concepcao de formulacoes de porcelanatos

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, V.S. de; Ferreira, E.C.; Oliveira, T.M. de; Freitas, K.D. de Araujo; Soares Filho, J.E.; Sousa, F.J.P. de, E-mail: vanessaalmeida90@gmail.com [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2016-07-01

    The porcelain is the more advanced product among traditional ceramics due to the high technology used in its manufacture and its excellent technological and aesthetic properties. Due to the continuing worldwide development, kaolin processing industries have increased their productivity and consequently generating large amounts of waste, contributing to environmental degradation. Studies are being conducted to analyze the incorporation of such wastes in the ceramic mass compositions. The objective of this study was to evaluate 4 formulations of porcelain as the possibility of using waste coming from the last stage of kaolin processing. Processing occurred by wet grinding process, with uniaxial compacting pressure of 45 MPa after heat treatment at 1250 ° C. Technological tests were carried out physical and mechanical product. The results showed that the addition of fine kaolin residue was presented as an efficient alternative for the porcelain industry. (author)

  8. Discussion on the origin of bleached sandstone of Qianjiadian uranium deposit

    International Nuclear Information System (INIS)

    Pang Yaqing; Xiang Weidong; Li Tiangang; Chen Xiaolin; Xia Yuliang

    2007-01-01

    Qianjiadian uranium deposit is a sandstone-type uranium deposit that has been discovered in Songliao Basin in recent years. Uranium ore bodies are planar or lenticular in shape and under the control of the contact between gray sandstones and bleached sandstones. The bleached sandstone is white in color, cemented loosely, nearly without TOC and pyrite contained and rich in uranium. Geochemical characteristics and types and assemblages of clay minerals of the bleached sandstone reveal that the bleached sandstone is the product of oxidation of the interlayer oxidation zone, and it is a part of the interlayer oxidation zone. The main reasons for white color of the bleached sandstone are transfer of iron ion, oxidation of TOC and kaolinization of sandstone. (authors)

  9. Mineralogical characterization and beneficiation study of kaolin from Equador (RN and Junco do Seridó (PB to increase the brightness index

    Directory of Open Access Journals (Sweden)

    V. M. J. S. Campos

    Full Text Available Abstract Kaolin is a rock composed mainly of kaolinite. It is used in many industrial segments, such as paper and ceramics. However, for these uses it is necessary to submit the ore to appropriate beneficiation, which generally involves magnetic separation and chemical bleaching, aiming to remove iron oxide and hydroxide, raising brightness index. This work reports the mineralogical characterization and analysis of the beneficiation of three samples of kaolin, two from Equador (Rio Grande do Norte - RN and the third from Junco do Seridó (Paraíba - PB. The samples were submitted to granulometric classification in sieve of 44 μm, magnetic separation in a magnetic induction of 14000 gauss, and chemical bleaching with sodium dithionite during 240 min. The processes were divided into two beneficiation routes. X-ray diffraction, chemical analysis by X-ray fluorescence and scanning electron microscopy were used for mineralogical characterization of the ore and measurement of the brightness index, while electron paramagnetic resonance was applied to study the variation of iron oxides and hydroxides during beneficiation. The results indicate that just 30 min of chemical bleaching without magnetic separation was sufficient to increase the brightness index from 78.2 to 90.2% and from 91.3 to 95.7% in the two samples from Equador (RN and from 86.9 to 90.4% in the sample from Junco do Seridó (PB. The magnetic separation, although causing a small increase in the brightness index, was inefficient for removal of iron oxides and hydroxides. The results indicated no need for using magnetic separation in plants for beneficiation of kaolin from these two locations, providing the reduction of production costs allowing better exploitation of the ore.

  10. Synthesis and characterization of a novel Mg–Al hydrotalcite-loaded kaolin clay and its adsorption properties for phosphate in aqueous solution

    International Nuclear Information System (INIS)

    Deng, Lin; Shi, Zhou

    2015-01-01

    Highlights: • Kaolin clay was coalesced with Mg–Al hydrotalcite to form composite adsorbent (MKC). • MKC was synthesized through modified co-precipitation method. • MKC gave high adsorption of phosphate over a wide pH range of 2.5–9.5. • MKC is an economical and environmentally friendly adsorbent for phosphate removal and recycling. - Abstract: The mesoporous modified kaolin clay (MKC) was synthesized by loading Mg–Al hydrotalcite onto kaolin clay through coprecipitation method and applied for adsorption of phosphate from aqueous solution. Several techniques, including Brunauer–Emmett–Teller (BET), thermal analysis (TG–DTA), and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the adsorbents. The effects of adsorbent dosage, solution pH, initial phosphate concentration, contact time, temperature, and coexistent anions on phosphate adsorption have been investigated. MKC exhibited a strong uptake affinity to phosphate in a wide pH range of 2.5–9.5, with the maximum adsorptive removal of 98.03%, at adsorbent dosage of 0.2 g/50 mL, pH 7.5, and initial phosphate concentration 25 mg L −1 . The adsorption kinetics followed the pseudo-second-order kinetic model. The Langmuir isothermal model well described the adsorption isotherm data, showing a maximum adsorption capacity for phosphate up to 11.92 mg g −1 at 298 K. The obtained thermodynamic parameters revealed that the adsorption of phosphate onto MKC was an exothermic and spontaneous process. Coexistent chloride, nitrate, and sulfate ions displayed an adverse effect on phosphate adsorption following the order of SO 4 2− > NO 3 − > Cl − . A mechanism of adsorption that involved (i) electrostatic attraction of hydroxyl groups of the adsorbent with negatively charged phosphate ions, and (ii) anion exchange of NO 3 − ions that were associated with the surface or interlayer of the adsorbent with anionic phosphate ions in solution, was proposed

  11. Properties of Portland-Composite Cements with metakaolin: Commercial and manufactured by Thermal Activation of Serbian Kaolin Clay

    Directory of Open Access Journals (Sweden)

    Mitrovic A.

    2012-09-01

    Full Text Available Portland-composite cements (CEM II were prepared with addition of 5 to 35% of metakaolin (MK, manufactured by thermal activation/calcination of Serbian kaolin clay, and commercial matakaolin (CMK. Performance of the composite cements was evaluated, through the setting time (initial and final, compressive strengths (for ages 2, 7, 28, 90 and 180 days and soundness, and compared with control cement (Portland cement – CEM I. Setting time (initial and final is accelerated in Portlandcomposite cements, for both metakaolins used. The acceleration is higher in cement with addition of commercial metakaolin. Lower compressive strength is obtained after 2 days of curing for all Portland-composite cements in comparison with control cement, since pozzolanic reaction still did not show its effect. After 7 days, pozzolanic reaction show its effect, manifested as compressive strength increase of Portland-composite cements with addition of up to 35% of CMK, and 25% in the case of cements with MK. After 28 days compressive strength was higher than that for control cement for cements prepared with addition of CMK, and with addition of up to 25% MK. After 90 days increased compressive strength was noticed with addition of 10 - 20% of CMK, and with 10 and 15% of MK, while after 180 days addition of both metakaolins influences compressive strength decrease. The results of the soundness, 0.5 mm for CEM I, and 1.0 mm in most Portland-composite cements indicate soundness increase with addition of metakaolins. Generally, better performance of Portland-composite cements was obtained with addition of commercial metakaolin, which may be attributed to the differences in the pozzolanic activity of the applied metakaolins, 20.5 MPa and 14.9 MPa for CMK and MK, respectively. By our previous findings pozzolanic activity of the thermally activated clay may be increased by subsequent milling of the metakaolin manufactured by thermal activation process.

  12. Physicochemical properties of cross-linked poly-gamma-glutamic acid and its flocculating activity against kaolin suspension

    International Nuclear Information System (INIS)

    Taniguchi, M.; Kato, K.; Shimauchi, A.; Ping, X.; Fujita, K.; Tanaka, T.; Tarui, Y.; Hirasawa, E.

    2005-01-01

    Cross-linked poly-Gamma-glutamic acid (C-L Gamma-PGA) was prepared with Gamma-PGA irradiated with Gamma-PGA at various kGy values. The physicochemical properties including viscosity and water absorption capacity were compared between C-L Gamma-PGA and several typical flocculating agents. The viscosity of C-L Gamma-PGA increased with the dose of Gamma-lrradiatio, although the water absorption capacity of C-L Gamma-PGA did not, which showed a maximum of 1005.6 ml/g at 20 kGy. Flocculating activity against kaolin suspension was not observed for any of the test compounds when used singly. However, the activity of C-L Gamma-PGA markedly increased following the addition of polyaluminum chloride. The activity increased with temperature up to 80deg C and remained at 80 deg C of heat pretreatment for 1 h, but did not at more than 50 deg C of beat pretreatment for 24 h. The activity was also observed within a pH range of 4.5-10.0. Roth the water absorption capacity and flocculating activity of C-L Gamma-PGA decreased in parallel with increasing NaCl concentration, suggesting that the hocculating activity of C-L Gamma-PGA was associated with its water absorption capacity, rather than viscosity. An investigation of the effects of various cations on the flocculating activity of C-L Gamma-PGA showed that only trivalent catlons had a synergistic effect. The mechanism of C-L Gamma-PGA flocculating activity is discussed based on the results of preliminary experiments

  13. Bulk Fluidity and Apparent Wall Slip of Aqueous Kaolin Suspensions Studied Using the Cone-cone (KK) Sensor: The Effect of Concentration and Temperature.

    Czech Academy of Sciences Publication Activity Database

    Pěnkavová, Věra; Tihon, Jaroslav; Wein, Ondřej

    2016-01-01

    Roč. 511, DEC 20 (2016), s. 272-284 ISSN 0927-7757 R&D Projects: GA MŠk(CZ) LD13018 Grant - others:COST- European Coperation in Science and Technology(XE) MP1305; COST- European Coperation in Science and Technology(XE) MP1106 Program:LD COST Institutional support: RVO:67985858 Keywords : aqueous kaolin suspensions * apparent wall slip * cone-cone (KK) sensor Subject RIV: CI - Industrial Chemistry , Chemical Engineering Impact factor: 2.714, year: 2016

  14. 国内外玻璃纤维用高岭土的质量差距及提高我国高岭土质量的对策%Differences of Kaolin Quality for Glass Fibers Made in China and Abroad and Improving Measures of Kaolin Quality Made in China

    Institute of Scientific and Technical Information of China (English)

    韩利雄; 姚远; 刘国斌

    2011-01-01

    Kaolins are one of important materials for E-glass fibers, which accounts for about 1/3 of blend mass. But the high-end market of kaolin for glass fibers was dominated by imports in China. Three kinds of kaolin samplespro-duced by ITC.Yichang and Yunnan for glass fibers were studied in this paper. The differences in chemical composition, phase,microstructure and granulometric composition were compared in detail by XRS,XRD,SEM and LPS. The research found that products of ITC had obvious advantages in product purity, particle size control and quality stability. In fact,the quality of domestic Kaolins is not bad,but because it is lack of specific quality standard and limited by the processing level of domestic non-metallic mineral, high-quality products cannot be obtained. In the future, kaolin industry should become bigger and stronger by integration as soon as possible, and try hard to improve the processing level of kaolin such as ore dressing,homogenization,etc,to fill the gap in the high-grade kaolin products for glass fibers.%高岭土是E-玻璃纤维的重要原料之一,其用量可占配合料的三分之一,但国内玻纤用高岭土高端市场一直被进口产品所占据.选取了美国ITC进口高岭土、宜昌硬质高岭土和云南水洗高岭土这三种有代表性的玻纤用高岭土,通过荧光光谱分析、X射线衍射分析、扫描电镜分析和激光粒度分析详细对比了它们在化学成分、物相组成、微观形貌和粒度分布四方面的差异.研究发现,美国玻纤用高岭土在产品纯度、粒度控制和质量稳定性方面有明显优势;国内玻纤用高岭土矿源品质并不差,只是由于缺乏专门的质量标准,同时受限于国内非金属矿产加工水平,而无法生产出高质量的产品.未来我国高岭土行业应尽快通过整合做大做强,努力提高高岭土选矿、均化等加工工艺水平,填补国内高档玻纤用高岭土产品空白.

  15. Characterization of kaolin and granite waste for formulation of porcelain stoneware tiles; Caracterizacao de caulim e de residuo de granito para formulacao de gres porcelanato

    Energy Technology Data Exchange (ETDEWEB)

    Luna da Silveira, G.C. [Instituto Federal do Rio Grande do Norte (IFRN), RN (Brazil); Acchar, W.; Gomes, U.U.; Silva, B.K.O.; Luna da Silveira, R.V. [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil); Labrincha, J.A.; Costa, M.C.P., E-mail: glebacoelli@hotmail.com [Universidade de Aveiro (Portugal)

    2016-07-01

    To produce a stoneware tiles is necessary develop a formulation that satisfies their structural characteristics, micro-structural, physical and mechanical properties. Thus, in order to create a formulation for porcelain stoneware tiles that give use to kaolin and granite waste used in the production of ceramic materials were asked the following characterizations: chemical analysis, mineralogical, thermal and particle size. We found that in the kaolin sample it presents a rate of silicon oxide and aluminum oxide similar to those found in the work of other investigators, about 45.23% SiO2 and 37.39% Al{sub 2}O{sub 3}. In the granite waste, the percentage of silicon oxide and aluminum oxide are also similar to those observed in other studies, with about 74.89% SiO2 and 10.54% Al{sub 2}O{sub 3}. Both the percentage of SiO{sub 2} and Al{sub 2}O{sub 3} founded in these two samples satisfy the percentage required in the manufacturing of porcelain stoneware tiles. (author)

  16. Moisture expansion of ceramic tiles produced using kaolin and granite wastes; Expansao por umidade de revestimentos ceramicos incorporados com residuos de granito e caulim

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, A.M.G.D.; Cartaxo, J.M.; Santana, L.N.L; Neves, G.A.; Ferreira, H.C., E-mail: ana.duartemendonca@gmail.com, E-mail: gelmires@dema.ufcg.edu.br, E-mail: lisiane@dema.ufcg.edu.br [Unidade Academica de Engenharia de Materiais, Universidade Federal de Campina Grande,Campina Grande, PB (Brazil); Menezes, R.R. [Departamento de Engenharia de Materiais, Universidade Federal da Paraiba, Joao Pessoa, PB (Brazil)

    2012-04-15

    Moisture expansion (ME) is the term used to describe the expansion of ceramic materials due to the adsorption of water. ME usually occurs slowly and is relatively small, but, it can damage the ceramic tiles adhesion to the underlayment, craze the glaze and lead to the development of cracks on ceramics bricks. In this work kaolin and granite wastes were incorporated in ceramic compositions aiming study their influence on the ME of ceramic tiles. Raw materials were processed and submitted to characterization: physical and mineralogical by laser diffraction particle size analysis, chemical analysis, thermo differential and thermogravimetric analysis and X-ray diffraction. Results showed that kaolin and granite wastes can be incorporated in ceramic composition because display characteristics similar to conventional not plastic ceramic materials, providing satisfactory ME results when compared to the ME limit value of 0.6 mm/m (0.06%) indicated by the ABNT for ceramic tiles. Compositions containing up to 20% of waste can be produced when firing above 1000 deg C. (author)

  17. Cationic polyelectrolyte induced separation of some inorganic contaminants and their mixture (zirconium silicate, kaolin, K-feldspar, zinc oxide) as well as of the paraffin oil from water.

    Science.gov (United States)

    Ghimici, Luminita

    2016-03-15

    The flocculation efficiency of a cationic polyelectrolyte with quaternary ammonium salt groups in the backbone, namely PCA5 was evaluated on zirconium silicate (kreutzonit), kaolin, K- feldspar and zinc oxide (ZnO) suspensions prepared either with each pollutant or with their mixture. The effect of several parameters such as settling time, polymer dose and the pollutant type on the separation efficacy was evaluated and followed by optical density and zeta potential measurements. Except for ZnO, the interactions between PCA5 and suspended particles led to low residual turbidity values (around 4% for kreutzonit, 5% for kaolin and 8% for K-feldspar) as well as to the reduction of flocs settling time (from 1200 min to 30 min and 120 min in case of kaolinit and K-feldspar, respectively), that meant a high efficiency in their separation. The negative value of the zeta potential and flocs size measurements, at the optimum polymer dose, point to contribution from charge patch mechanism for the particles flocculation. A good efficiency of PCA5 in separation of paraffin oil (a minimum residual turbidity of 9.8%) has been also found. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Computer simulation of mobilization and mixing of kaolin with submerged liquid jets in 25,000-gallon horizontal cylindrical tanks

    International Nuclear Information System (INIS)

    Eyler, L.L.; Mahoney, L.A.

    1995-03-01

    This report presents and analyzes results of computer model simulation of mobilization and mixing of kaolin using the TEMPEST code. The simulations are conducted in a horizontal cylindrical geometry replicating a 95 m 3 (25,000 gal) test tank at ORNL, which is scaled to approximate Melton Valley Storage tanks, which are 190 m 3 (50,000 gal). Mobilization and mixing is accomplished by two submerged liquid jets. Two configurations are simulated, one with the jets located at the center of the tank lengthwise and one with the jets located 1/4 tank length from one end. Computer simulations of both jet and suction configurations are performed. Total flow rates of 50, 100, and 200 gpm are modeled, corresponding to jet velocities of 1.52, 3.05, 6.10 m/s (5, 10, 20 ft/s). Calculations were performed to a time of 2 h for the center jet location and to a little over 1 h for the quarter jet location. This report presents computer and fluid properties model basis, preliminary numerical testing, and results. The results are presented in form of flow field and sludge layer contours. Degree of mobilization is presented as fraction of initial sludge layer remaining as a function of time. For the center jet location at 200 gpm, the sludge layer is completely mobilized in just over 1 h. For 100 gpm flow, about 5% of the sludge layer remains after 2 h. For 50 gpm flow, nearly 40% of the initial sludge layer remains after 2 h. For the quarter jets at 200 gpm, about 10% of the initial sludge layer remains after 1 h. For 100 gpm, about 40% of the sludge layer remains after 1 h. The boundary of the sludge layer is defined as 98% max packing for the particles. Mixing time estimates for these cases range from between 9.4 h and 16.2 h. A more critical evaluation and comparison of predictions and the test results is needed

  19. Infraordinary Deposits

    DEFF Research Database (Denmark)

    2016-01-01

    The exhibition Infraordinary Deposits presents three works in progress by PhD Fellow Espen Lunde Nielsen from the on-going PhD project Architectural Probes of the Infraordinary: Social Coexistence through Everyday Spaces. The infraordinary is understood as the opposite of the extraordinary...... and as that which is ‘worn half-invisible’ by use. Nevertheless, these unregarded spaces play a vital role to the social dimension of the city. The selected projects (‘urban biopsies’) on display explore how people coexist through these spaces and within the city itself, either through events in real......, daily 8.45 – 15.00 Where: Aarhus School of Architecture, The Canteen, Nørreport 18, 8000 Aarhus C...

  20. Synthesis and characterization of a novel Mg–Al hydrotalcite-loaded kaolin clay and its adsorption properties for phosphate in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Lin, E-mail: denglinlyn@126.com; Shi, Zhou, E-mail: 369329062@qq.com

    2015-07-15

    Highlights: • Kaolin clay was coalesced with Mg–Al hydrotalcite to form composite adsorbent (MKC). • MKC was synthesized through modified co-precipitation method. • MKC gave high adsorption of phosphate over a wide pH range of 2.5–9.5. • MKC is an economical and environmentally friendly adsorbent for phosphate removal and recycling. - Abstract: The mesoporous modified kaolin clay (MKC) was synthesized by loading Mg–Al hydrotalcite onto kaolin clay through coprecipitation method and applied for adsorption of phosphate from aqueous solution. Several techniques, including Brunauer–Emmett–Teller (BET), thermal analysis (TG–DTA), and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the adsorbents. The effects of adsorbent dosage, solution pH, initial phosphate concentration, contact time, temperature, and coexistent anions on phosphate adsorption have been investigated. MKC exhibited a strong uptake affinity to phosphate in a wide pH range of 2.5–9.5, with the maximum adsorptive removal of 98.03%, at adsorbent dosage of 0.2 g/50 mL, pH 7.5, and initial phosphate concentration 25 mg L{sup −1}. The adsorption kinetics followed the pseudo-second-order kinetic model. The Langmuir isothermal model well described the adsorption isotherm data, showing a maximum adsorption capacity for phosphate up to 11.92 mg g{sup −1} at 298 K. The obtained thermodynamic parameters revealed that the adsorption of phosphate onto MKC was an exothermic and spontaneous process. Coexistent chloride, nitrate, and sulfate ions displayed an adverse effect on phosphate adsorption following the order of SO{sub 4}{sup 2−} > NO{sub 3}{sup −} > Cl{sup −}. A mechanism of adsorption that involved (i) electrostatic attraction of hydroxyl groups of the adsorbent with negatively charged phosphate ions, and (ii) anion exchange of NO{sub 3}{sup −} ions that were associated with the surface or interlayer of the adsorbent with anionic phosphate ions in

  1. Kaolins in Uruguay

    International Nuclear Information System (INIS)

    Spoturno, J.; Coronel, N.

    1980-01-01

    This work belongs to the Syllabus or Mundial monograph about caolines. Its was organized by the number 23 working group caolines genesis of the International geological correlation Unesco programme. History, geology, tectonic development, sedimentation, dating and geochemistry aspects were given in this report.

  2. Cordierite obtaining by reactive sintering of kaolin, tal and transition alumina; Obtencao de ceramicas a base de mulita-cordieta via sinterizacao reativa de caulim, talco e alumina

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Filho, Humberto Dias de; Sales, Lindemberg Felismino; Goncalves, Joao de Freitas; Macedo, Daniel Araujo de [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Departamento de Engenharia de Materiais

    2016-07-01

    Cordierite and mullite are important applications in the manufacture of ceramic products with high resistance to thermal shock. The present work aimed to obtaining ceramics based on cordierite (2MgO.2Al2O3.5SiO2) and mullite (3Al2O3.2SiO2) via reactive sintering of one formulation containing kaolin ceramics, talc and alumina. Uniaxially pressed tablet to 125 MPa were sintered between 1100 and 1400 ° C for 1 h. The sintering temperature effect in the phase composition was evaluated by X-ray diffraction. The morphological characterization was performed by scanning electron microscopy. Samples sintered at 1300 ° C had 10 wt% of spinel (MgAl2O4) as secondary and apparent phase density 2.56 g / cm3. (author)

  3. For production of ceramic plates coating using waste kaolin, granite and marble; Caracterizacao de residuos de caulim, granito e marmore para uso em massas ceramicas

    Energy Technology Data Exchange (ETDEWEB)

    Sales, J.L.; Morais, C.R.S.; Lima, L.M.R.; Altidis, M.E.D., E-mail: josyanne27@yahoo.com.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2011-07-01

    The objective is to benefit and characterize waste from kaolin, marble and granite studying their thermal properties and spectroscopic in employment perspective on ceramic production of flooring boards. The residues were benefited through the process of dry grinding mill in greyhounds and passed through sieve 0.074 mm (ABNT No. 200), observing their suitability for the formulation of ceramic pastes. Tests were performed physicochemical characterization (particle size analysis, X-ray fluorescence and X-ray diffraction) and thermal (differential thermal analysis and thermogravimetry). The results showed that these residues showed satisfactory properties for the purpose for which it proposes, and contribute to reducing environmental impacts, allowing the reuse of the production of ceramic plates (author)

  4. Incorporation of waste and fiber kaolin caroa panels in Medium Density Fiberboard - MDF; Incorporacao de residuos de caulim e fibras de caroa em paineis de media densidade- MDF

    Energy Technology Data Exchange (ETDEWEB)

    Bezerra, A.F.C.; Santana, L.N.L.; Neves, G.A.; Carvalho, L.H. de; Lopes, F.F.M., E-mail: anaflavia.dema@yahoo.com.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2012-07-01

    Medium-density panels are composites molded under high temperature and pressure which have physical and mechanical properties similar to those of solid wood. Their composition includes eucalyptus grandis fibers and pinus elliotii fibers, but other fibers can be used such as caroa fibers. The goal of this work was to manufacture panels which kaolin waste and caroa fibers and compare their physical, chemical and mechanical of these panels with a others. Both residue and the fibers were characterized by: differential thermal analysis, thermal gravimetric analysis and Xray diffraction. Through the process of pressing the test specimens were fabricated, test samples were evaluated by three point bending, internal bond, water absorption and swelling in thickness. The samples have low levels of thickness swelling, flexural strength and higher tensile and absorption content relative to commercial MDF. (author)

  5. Preparation and characterization of ZnO microfiltration membrane and its support using kaolin (DD3 and CaCO3

    Directory of Open Access Journals (Sweden)

    B. Boudaira

    Full Text Available Abstract The objective of the present paper was to prepare a ceramic support with membrane. Tubular ceramic supports prepared from kaolin (DD3 and calcium carbonate with 6 and 10 mm inner and outer diameters, respectively, were extruded and sintered at 1200 °C. It has been found that sintered supports had interesting characteristics: average pore size of about 5µm, porosity of about 50%, and monomodal pore size distribution. This support was used to be substrate for a membrane layer of microfiltration. This membrane layer was elaborated from zinc oxide, using slip casting technique. The specimens were subsequently sintered at 1000 °C. The microstructure and porosity as well as the permeability have also been studied. It has been found that the average pore size was about 1.2µm, the layer thickness was ~33µm, and the water permeability measured was about 880 L.h-1.m-2.bar-1.

  6. Waste characterization emanated from kaolin submitted the improvement to process hydrocycloning; Caracterizacao do residuo provindo do beneficiamento do caulim submetido ao processo de hidrociclonagem

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa Neto, M.C.; Nunes, A.S.; Caetano, A.L.A.; Marques, V.C.; Macedo, D.A.; Ferreira, H.S.; Dutra, R.P.S., E-mail: netobarbosa.2@gmail.com [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Departamento de Engenharia de Materiais

    2016-07-01

    The hydrocyclones are equipment commonly used for separation of particles by size. The resulting material of this process usually presents different characteristics of the material, which was not subjected to treatment. Therefore, a study of the waste characteristics derived from kaolin processing submitted to hydrocycloning process compared to the same residue without going through the process was executed. The different samples were characterized by X-ray diffraction, X-ray fluorescence, particle size analysis and thermal analysis. The results indicate that the hydrocycloning not modify the mineralogical structure nor chemical material. The particle size analysis identified that the fine fraction, resulting from the process, presented particle size lower than the reference material. (author)

  7. Magnetic resonance imaging indicators of blood-brain barrier and brain water changes in young rats with kaolin-induced hydrocephalus.

    Science.gov (United States)

    Del Bigio, Marc R; Slobodian, Ili; Schellenberg, Angela E; Buist, Richard J; Kemp-Buors, Tanya L

    2011-08-11

    Hydrocephalus is associated with enlargement of cerebral ventricles. We hypothesized that magnetic resonance (MR) imaging parameters known to be influenced by tissue water content would change in parallel with ventricle size in young rats and that changes in blood-brain barrier (BBB) permeability would be detected. Hydrocephalus was induced by injection of kaolin into the cisterna magna of 4-week-old rats, which were studied 1 or 3 weeks later. MR was used to measure longitudinal and transverse relaxation times (T1 and T2) and apparent diffusion coefficients in several regions. Brain tissue water content was measured by the wet-dry weight method, and tissue density was measured in Percoll gradient columns. BBB permeability was measured by quantitative imaging of changes on T1-weighted images following injection of gadolinium diethylenetriamine penta-acetate (Gd-DTPA) tracer and microscopically by detection of fluorescent dextran conjugates. In nonhydrocephalic rats, water content decreased progressively from age 3 to 7 weeks. T1 and T2 and apparent diffusion coefficients did not exhibit parallel changes and there was no evidence of BBB permeability to tracers. The cerebral ventricles enlarged progressively in the weeks following kaolin injection. In hydrocephalic rats, the dorsal cortex was more dense and the white matter less so, indicating that the increased water content was largely confined to white matter. Hydrocephalus was associated with transient elevation of T1 in gray and white matter and persistent elevation of T2 in white matter. Changes in the apparent diffusion coefficients were significant only in white matter. Ventricle size correlated significantly with dorsal water content, T1, T2, and apparent diffusion coefficients. MR imaging showed evidence of Gd-DTPA leakage in periventricular tissue foci but not diffusely. These correlated with microscopic leak of larger dextran tracers. MR characteristics cannot be used as direct surrogates for water

  8. Magnetic resonance imaging indicators of blood-brain barrier and brain water changes in young rats with kaolin-induced hydrocephalus

    Directory of Open Access Journals (Sweden)

    Del Bigio Marc R

    2011-08-01

    Full Text Available Abstract Background Hydrocephalus is associated with enlargement of cerebral ventricles. We hypothesized that magnetic resonance (MR imaging parameters known to be influenced by tissue water content would change in parallel with ventricle size in young rats and that changes in blood-brain barrier (BBB permeability would be detected. Methods Hydrocephalus was induced by injection of kaolin into the cisterna magna of 4-week-old rats, which were studied 1 or 3 weeks later. MR was used to measure longitudinal and transverse relaxation times (T1 and T2 and apparent diffusion coefficients in several regions. Brain tissue water content was measured by the wet-dry weight method, and tissue density was measured in Percoll gradient columns. BBB permeability was measured by quantitative imaging of changes on T1-weighted images following injection of gadolinium diethylenetriamine penta-acetate (Gd-DTPA tracer and microscopically by detection of fluorescent dextran conjugates. Results In nonhydrocephalic rats, water content decreased progressively from age 3 to 7 weeks. T1 and T2 and apparent diffusion coefficients did not exhibit parallel changes and there was no evidence of BBB permeability to tracers. The cerebral ventricles enlarged progressively in the weeks following kaolin injection. In hydrocephalic rats, the dorsal cortex was more dense and the white matter less so, indicating that the increased water content was largely confined to white matter. Hydrocephalus was associated with transient elevation of T1 in gray and white matter and persistent elevation of T2 in white matter. Changes in the apparent diffusion coefficients were significant only in white matter. Ventricle size correlated significantly with dorsal water content, T1, T2, and apparent diffusion coefficients. MR imaging showed evidence of Gd-DTPA leakage in periventricular tissue foci but not diffusely. These correlated with microscopic leak of larger dextran tracers. Conclusions MR

  9. Economical Atomic Layer Deposition

    Science.gov (United States)

    Wyman, Richard; Davis, Robert; Linford, Matthew

    2010-10-01

    Atomic Layer Deposition is a self limiting deposition process that can produce films at a user specified height. At BYU we have designed a low cost and automated atomic layer deposition system. We have used the system to deposit silicon dioxide at room temperature using silicon tetrachloride and tetramethyl orthosilicate. Basics of atomic layer deposition, the system set up, automation techniques and our system's characterization are discussed.

  10. Electro-Deposition Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The electro-deposition laboratory can electro-deposit various coatings onto small test samples and bench level prototypes. This facility provides the foundation for...

  11. Atmospheric Deposition Modeling Results

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset provides data on model results for dry and total deposition of sulfur, nitrogen and base cation species. Components include deposition velocities, dry...

  12. Calcium Pyrophosphate Deposition (CPPD)

    Science.gov (United States)

    ... Patient / Caregiver Diseases & Conditions Calcium Pyrophosphate Deposition (CPPD) Calcium Pyrophosphate Deposition (CPPD) Fast Facts The risk of ... young people, too. Proper diagnosis depends on detecting calcium pyrophosphate crystals in the fluid of an affected ...

  13. Effects of using kaolin waste and granite waste as raw materials for the production of low-water absorption ceramic tiles; Efeitos da co-utilizacao dos residuos do beneficiamento do caulim e da extracao do granito rain forest para a producao de revestimentos ceramicos com baixa absorcao de agua

    Energy Technology Data Exchange (ETDEWEB)

    Freires, H.P.; Argonz, R.; Nogueira, R.E.F.Q.; Sasaki, J.M., E-mail: argonz@ufc.br [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil); Sales, J.C. [Universidade do Vale do Aracau (UVA), Crateus, CE (Brazil)

    2012-07-01

    This study aims to evaluate the potential of co-use of granite waste (Rain Forest) and kaolin waste as raw material for the manufacture of ceramic coating of low water absorption. Raw materials were characterized by X-ray diffraction. Kaolin residue was added to the residue of granite in the following proportions (in wt%): 0, 10, 20, 30, 40 and 50%. Specimens were fabricated by uniaxial pressing and fired at 1175,1200 and 1225 deg C. Studies of firing linear shrinkage, water absorption, apparent porosity, apparent density and tensile bending test (or rupture modulus) were conducted. The temperature of 1225 deg C allowed the use of a mixture of 50% granite residue and 50% kaolin residue. Ceramic parts made from that mixture exhibited the maximum values required by the Brazilian Standard NBR 13818 for water absorption, shrinkage and density. (author)

  14. Acid Deposition Phenomena

    International Nuclear Information System (INIS)

    Ramadan, A.E.K.

    2004-01-01

    Acid deposition, commonly known as acid rain, occurs when emissions from the combustion of fossil fuels and other industrial processes undergo complex chemical reactions in the atmosphere and fall to the earth as wet deposition (rain, snow, cloud, fog) or dry deposition (dry particles, gas). Rain and snow are already naturally acidic, but are only considered problematic when less than a ph of 5.0 The main chemical precursors leading to acidic conditions are atmospheric concentrations of sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ). When these two compounds react with water, oxygen, and sunlight in the atmosphere, the result is sulfuric (H 2 SO 4 ) and nitric acids (HNO 3 ), the primary agents of acid deposition which mainly produced from the combustion of fossil fuel and from petroleum refinery. Airborne chemicals can travel long distances from their sources and can therefore affect ecosystems over broad regional scales and in locations far from the sources of emissions. According to the concern of petroleum ministry with the environment and occupational health, in this paper we will discussed the acid deposition phenomena through the following: Types of acidic deposition and its components in the atmosphere Natural and man-made sources of compounds causing the acidic deposition. Chemical reactions causing the acidic deposition phenomenon in the atmosphere. Factors affecting level of acidic deposition in the atmosphere. Impact of acid deposition. Procedures for acidic deposition control in petroleum industry

  15. Atividade pozolânica dos resíduos do beneficiamento do caulim para uso em argamassas para alvenaria Pozolanic activity of kaolin processing residues for use in masonry mortars

    Directory of Open Access Journals (Sweden)

    Romualdo R. Menezes

    2009-12-01

    Full Text Available A indústria do beneficiamento do caulim gera enorme quantidade de resíduos, descartados indiscriminadamente no meio ambiente; assim, este trabalho tem por objetivo analisar a viabilidade técnica e a atividade pozolânica dos resíduos do beneficiamento do caulim para a produção de argamassas. Os resíduos foram caracterizados através da determinação de sua distribuição granulométrica e composição química, difração de raios X e análise térmica diferencial e gravimétrica; em seguida, determinou-se o índice de atividade pozolânica dos resíduos de caulim com a cal e o cimento Portland. Argamassas de cimento:cal:areia foram preparadas e o resíduo, na condição natural e após queima a 600 °C por 2 h, substituiu parcialmente o cimento nas proporções de 5, 10, 15 e 20% em massa. Corpos-de-prova foram moldados e determinada sua resistência a compressão simples. Conclui-se, com base nos resultados, que os resíduos são constituídos de caulinita, mica e quartzo e que a utilização do resíduo calcinado aumenta a resistência das argamassas após 28 dias de cura em até 150%.The kaolin processing industry generates large amounts of waste, which is indiscriminately dumped in open-air sites. This work evaluates the technical suitability and pozolanic activity of kaolin processing wastes for the production of mortars. The wastes were characterized by particle size distribution and chemical composition determination, X-ray diffraction and thermal differential and gravimetric analyses. The pozolanic activity index was determined using lime and Portland cement. Cement:lime:sand mortars were formulated and the kaolin wastes replaced cement by 5, 10, 15 and 20% on weight basis. The kaolin wastes were used in their natural condition and after thermal treatment at 600 °C for 2 h. Test specimens were produced and their compression strength determined. The results indicated that the waste consists of quartz, kaolinite and mica, and

  16. Preparation and solar-light photocatalytic activity of TiO2 composites: TiO2/kaolin, TiO2/diatomite, and TiO2/zeolite

    Science.gov (United States)

    Li, Y.; Li, S. G.; Wang, J.; Li, Y.; Ma, C. H.; Zhang, L.

    2014-12-01

    Three TiO2 loaded composites, TiO2/kaolin, TiO2/diatomite, and TiO2/zeolite, were prepared in order to improve the solar-light photocatalytic activity of TiO2. The results showed that the photocatalytic activity could obviously be enhanced by loading appropriate amount of inorganic mineral materials. Meanwhile, TiO2 content, heat-treatment temperature and heat-treatment time on the photocatalytic activity were reviewed. Otherwise, the effect of solar light irradiation time and dye concentration on the photocatalytic degradation of Acid Red B was investigated. Furthermore, the degradation mechanism and adsorption process were also discussed.

  17. Deposition Measurements in NSTX

    Science.gov (United States)

    Skinner, C. H.; Kugel, H. W.; Hogan, J. T.; Wampler, W. R.

    2004-11-01

    Two quartz microbalances have been used to record deposition on the National Spherical Torus Experiment. The experimental configuration mimics a typical diagnostic window or mirror. An RS232 link was used to acquire the quartz crystal frequency and the deposited thickness was recorded continuously with 0.01 nm resolution. Nuclear Reaction Analysis of the deposit was consistent with the measurement of the total deposited mass from the change in crystal frequency. We will present measurements of the variation of deposition with plasma conditions. The transport of carbon impurities in NSTX has been modelled with the BBQ code. Preliminary calculations indicated a negligible fraction of carbon generated at the divertor plates in quiescent discharges directly reaches the outer wall, and that transient events are responsible for the deposition.

  18. Shedding of ash deposits

    DEFF Research Database (Denmark)

    Zbogar, Ana; Frandsen, Flemming; Jensen, Peter Arendt

    2009-01-01

    Ash deposits formed during fuel thermal conversion and located on furnace walls and on convective pass tubes, may seriously inhibit the transfer of heat to the working fluid and hence reduce the overall process efficiency. Combustion of biomass causes formation of large quantities of troublesome...... ash deposits which contain significant concentrations of alkali, and earth-alkali metals. The specific composition of biomass deposits give different characteristics as compared to coal ash deposits, i.e. different physical significance of the deposition mechanisms, lower melting temperatures, etc....... Low melting temperatures make straw ashes especially troublesome, since their stickiness is higher at lower temperatures, compared to coal ashes. Increased stickiness will eventually lead to a higher collection efficiency of incoming ash particles, meaning that the deposit may grow even faster...

  19. Uraniferous surficial deposits

    International Nuclear Information System (INIS)

    Toens, P.D.; Hambleton-Jones, B.B.

    1980-10-01

    As a result of the discovery of uranium in surficial deposits of Tertiary to Recent age, in Australia and Southern Africa, increasing attention is being paid to the location and understanding of the genesis of these deposits. The paper discusses the definitions and terminology currently in use and a classification of these deposits is presented. It is concluded that in order to obtain a measure of clarity, the terms calcrete, gypcrete and dolocrete should not be used to describe the uraniferous valley-fill deposits of Southern Africa and Australia [af

  20. MAPLE deposition of nanomaterials

    International Nuclear Information System (INIS)

    Caricato, A.P.; Arima, V.; Catalano, M.; Cesaria, M.; Cozzoli, P.D.; Martino, M.; Taurino, A.; Rella, R.; Scarfiello, R.; Tunno, T.; Zacheo, A.

    2014-01-01

    The matrix-assisted pulsed laser evaporation (MAPLE) has been recently exploited for depositing films of nanomaterials by combining the advantages of colloidal inorganic nanoparticles and laser-based techniques. MAPLE-deposition of nanomaterials meeting applicative purposes demands their peculiar properties to be taken into account while planning depositions to guarantee a congruent transfer (in terms of crystal structure and geometric features) and explain the deposition outcome. In particular, since nanofluids can enhance thermal conductivity with respect to conventional fluids, laser-induced heating can induce different ablation thermal regimes as compared to the MAPLE-treatment of soft materials. Moreover, nanoparticles exhibit lower melting temperatures and can experience pre-melting phenomena as compared to their bulk counterparts, which could easily induce shape and or crystal phase modification of the material to be deposited even at very low fluences. In this complex scenario, this review paper focuses on examples of MAPLE-depositions of size and shape controlled nanoparticles for different applications highlights advantages and challenges of the MAPLE-technique. The influence of the deposition parameters on the physical mechanisms which govern the deposition process is discussed.

  1. MAPLE deposition of nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Caricato, A.P., E-mail: annapaola.caricato@le.infn.it [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Arima, V.; Catalano, M. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Cesaria, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Cozzoli, P.D. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Martino, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Taurino, A.; Rella, R. [Institute for Microelectronics and Microsystems, IMM-CNR, Via Monteroni, I-73100 Lecce (Italy); Scarfiello, R. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Tunno, T. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Zacheo, A. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy)

    2014-05-01

    The matrix-assisted pulsed laser evaporation (MAPLE) has been recently exploited for depositing films of nanomaterials by combining the advantages of colloidal inorganic nanoparticles and laser-based techniques. MAPLE-deposition of nanomaterials meeting applicative purposes demands their peculiar properties to be taken into account while planning depositions to guarantee a congruent transfer (in terms of crystal structure and geometric features) and explain the deposition outcome. In particular, since nanofluids can enhance thermal conductivity with respect to conventional fluids, laser-induced heating can induce different ablation thermal regimes as compared to the MAPLE-treatment of soft materials. Moreover, nanoparticles exhibit lower melting temperatures and can experience pre-melting phenomena as compared to their bulk counterparts, which could easily induce shape and or crystal phase modification of the material to be deposited even at very low fluences. In this complex scenario, this review paper focuses on examples of MAPLE-depositions of size and shape controlled nanoparticles for different applications highlights advantages and challenges of the MAPLE-technique. The influence of the deposition parameters on the physical mechanisms which govern the deposition process is discussed.

  2. Safety evaluation of new hemostatic agents, smectite granules, and kaolin-coated gauze in a vascular injury wound model in swine.

    Science.gov (United States)

    Kheirabadi, Bijan S; Mace, James E; Terrazas, Irasema B; Fedyk, Chriselda G; Estep, J Scot; Dubick, Michael A; Blackbourne, Lorne H

    2010-02-01

    In 2007, a potent procoagulant mineral called WoundStat (WS), consisting of smectite granules, received clearance from the Food and Drug Administration for marketing in the United States for temporary treatment of external hemorrhage. Previously, we found that microscopic WS particles remained in the injured vessels that were treated, despite seemingly adequate wound debridement. Thus, we investigated the thromboembolic risk of using WS when compared with kaolin-coated gauze, Combat Gauze (CG); or regular gauze, Kerlix (KX) to treat an external wound with vascular injuries in pigs. The right common carotid artery and external jugular vein of pigs were isolated and sharply transected (50%). After 30 seconds of free bleeding, the neck wounds were packed with WS, CG, or KX and compressed until hemostasis was achieved (n = 8 per group). Wounds were debrided after 2 hours, and vascular injuries were primarily repaired with suture. Blood flow was restored after infusing 1 L of crystalloid (no heparin or aspirin) and the wounds were closed. Two hours later, computed tomographic angiography was performed, and the wounds were reopened to harvest the vessels. The brains and lungs were recovered for gross and microscopic examination after euthanasia. No differences were found in baseline measurements. Thrombelastography showed similar hypercoagulability of the final blood samples when compared with baselines in all groups. All vessels treated with KX or CG were patent and had no thrombus or blood clot in their lumen. In contrast, seven of eight carotid arteries and six of eight jugular veins treated with WS developed large occlusive red thrombi and had no flow. Small clots and WS residues were also found in the lungs of two pigs. Histologically, significant endothelial and transmural damage was seen in WS-treated vessels with luminal thrombi and embedded WS residues. WS granules caused endothelial injury and significant transmural damage to the vessels that render them

  3. Rheology Modifiers Applied to Kaolin-Bentonite Slurries for SRNL WTP Pulse Jets Tank Pilot Work in Support of RPP at Hanford

    International Nuclear Information System (INIS)

    WILLIAM, DANIEL

    2005-01-01

    Savannah River National Laboratory (SRNL) was tasked to find and characterize the impact of rheological modifiers to a clay (Kaolin-Bentonite) slurry having 23.1 total wt percent solids, 1.165 g/ml, and Bingham Plastic yield stress of 13 Pa and plastic viscosity of 24 mPa-sec. The primary objective was to find rheological modifiers when blended with this clay slurry that would provide a vane yield stress of 300 Pa when the slurry was undisturbed for 24 hours. A secondary objective was to find a modifier that after shearing would produce a Bingham Plastic yield stress of 30 Pa and plastic viscosity of 30 mPa-sec. Two parallel paths were chosen with one examining a variety of organic/inorganic modifiers and another using just the inorganic modifier Laponite (R). The addition of organic modifiers hydroxyethylcellulose, hydroxypropylmethylcellulose, and hydroxypropylcellulose at a target 0.50 wt percent dramatically increased the vane yield stress over the range 311 - 724 Pa, and also increased the Bingham plastic yield stress and plastic viscosities over the range 33-112 Pa and 27-166 mPa-sec, respectively. The organic modifiers also showed elastic behavior, yielding a very unpredictable up flow curve. The 0.50 wt percent addition of inorganic modifiers magnesium aluminum silicate and hydrate magnesium aluminum silicate only increased the vane yield stress to 36-46 Pa and had little impact on the Bingham Plastic parameters. A range of an inorganic (2-4 wt percent magnesium aluminum silicate) and combination of a range of an inorganic (2-3 wt percent magnesium aluminum silicate) and organic (0.03-0.05 wt percent sodium carboxymethylcellulose) modifiers were then tested. These results showed that the target vane yield stress could be obtained but the Bingham Plastic yield stress and plastic viscosity were 3 times too high. Reducing the organic modifier weight percent by a few hundredths, the Bingham Plastic yield stress could be obtained, but then the vane yield stress

  4. Urban acid deposition

    Energy Technology Data Exchange (ETDEWEB)

    Conlan, D.E.; Longhurst, J.W.S.; Gee, D.R.; Hare, S.E.

    1991-07-01

    In this document results from the Greater Manchester Acid Deposition Survey (GMADS), an urban precipitation chemistry network, for 1990 are presented. Full analytical methods are described along with the precision and accuracy of the methods used. The spatial variability of precipitation chemistry and deposition over this urban region was investigated using a network of twenty collectors. Concentrations of non marine sulphate, ammonium, calcium and hydrogen, and nitrogen dioxide gas concentrations all show significant spatial variability. The spatial variability of the deposition rates of non marine sulphate, nitrate, ammonium, hydrogen and calcium were significant. (Author).

  5. Electroless atomic layer deposition

    Science.gov (United States)

    Robinson, David Bruce; Cappillino, Patrick J.; Sheridan, Leah B.; Stickney, John L.; Benson, David M.

    2017-10-31

    A method of electroless atomic layer deposition is described. The method electrolessly generates a layer of sacrificial material on a surface of a first material. The method adds doses of a solution of a second material to the substrate. The method performs a galvanic exchange reaction to oxidize away the layer of the sacrificial material and deposit a layer of the second material on the surface of the first material. The method can be repeated for a plurality of iterations in order to deposit a desired thickness of the second material on the surface of the first material.

  6. Alluvial Deposits in Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This coverage maps alluvial deposits throughout Iowa. This generally would include areas of alluvial soils associated with modern streams that are identified on...

  7. 75 FR 20041 - Deposits

    Science.gov (United States)

    2010-04-16

    ... transmission to (202) 906- 6518; or send an e-mail to [email protected] . OTS will post... DD implements the Truth in Savings Act, part of the Federal Deposit Insurance Corporation Improvement...

  8. Modeled Wet Nitrate Deposition

    Data.gov (United States)

    U.S. Environmental Protection Agency — Modeled data on nitrate wet deposition was obtained from Dr. Jeff Grimm at Penn State Univ. Nitrate wet depostion causes acidification and eutrophication of surface...

  9. Uranium deposit research, 1983

    International Nuclear Information System (INIS)

    Ruzicka, V.; LeCheminant, G.M.

    1984-01-01

    Research on uranium deposits in Canada, conducted as a prerequisite for assessment of the Estimated Additional Resources of uranium, revealed that (a) the uranium-gold association in rudites of the Huronian Supergroup preferably occurs in the carbon layers; (b) chloritized ore at the Panel mine, Elliot Lake, Ontario, occurs locally in tectonically disturbed areas in the vicinity of diabase dykes; (c) mineralization in the Black Sturgeon Lake area, Ontario, formed from solutions in structural and lithological traps; (d) the Cigar Lake deposit, Saskatchewan, has two phases of mineralization: monomineralic and polymetallic; (e) mineralization of the JEB (Canoxy Ltd.) deposit is similar to that at McClean Lake; (f) the uranium-carbon assemblage was identified in the Claude deposit, Carswell Structure; and (g) the Otish Mountains area, Quebec, should be considered as a significant uranium-polymetallic metallogenic province

  10. Automatic Payroll Deposit System.

    Science.gov (United States)

    Davidson, D. B.

    1979-01-01

    The Automatic Payroll Deposit System in Yakima, Washington's Public School District No. 7, directly transmits each employee's salary amount for each pay period to a bank or other financial institution. (Author/MLF)

  11. Deposition of acidifying compounds

    International Nuclear Information System (INIS)

    Fowler, D.; Cape, J.N.; Sutton, M.A.; Mourne, R.; Hargreaves, K.J.; Duyzer, J.H.; Gallagher, M.W.

    1992-01-01

    Inputs of acidifying compounds to terrestrial ecosystems include deposition of the gases NO 2 , NO, HNO 2 , HNO 3 , NH 3 and SO 2 and the ions NO 3- , NH 4+ , SO 4 2- and H + in precipitation, cloud droplets and particles. Recent research has identified particular ecosystems and regions in which terrestrial effects are closely linked with specific deposition processes. This review paper identifies areas in which important developments have occurred during the last five years and attempts to show which aspects of the subject are most important for policy makers. Amongst the conclusions drawn, the authors advise that current uncertainties in estimates of S and N inputs by dry deposition should be incorporated in critical load calculations, and that, in regions dominated by wet deposition, spatial resolution of total inputs should be improved to match the current scales of information on landscape sensitivity to acidic inputs. 44 refs., 9 figs

  12. Speleothem (Cave Deposit) Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, and other aspects of climate derived from mineral deposits found in caves. Parameter keywords describe what was measured...

  13. Gemstone deposits of Serbia

    Directory of Open Access Journals (Sweden)

    Miladinović Zoran

    2016-06-01

    Full Text Available Gemstone minerals in Serbia have never been regarded as an interesting and significant resource. Nevertheless, more than 150 deposits and occurrences have been recorded and some of them preliminarily explored in the last 50 years. The majority of deposits and occurrences are located within the Serbo-Macedonian metallogenic province and the most significant metallogenic units at the existing level of knowledge are the Fruska Gora ore district, Cer ore district, Sumadija metallogenic zone, Kopaonik metallogenic zone and Lece-Halkidiki metallogenic zone. The most important genetic type of deposits is hydrothermal, particularly in case of serpentinite/peridotite as host/parent rock. Placer deposits are also economically important. The dominant gemstones are silica minerals: chalcedony (Chrysoprase, carnelian, bluish chalcedony etc., jasper (picture, landscape, red etc., common opal (dendritic, green, milky white etc., silica masses (undivided, and quartz (rock crystal, amethyst etc.. Beside silica minerals significant gemstones in Serbia include also beryl (aquamarine, garnet (almandine and pyrope, tourmaline, fluorite, rhodochrosite, carbonate-silica breccia, carbonate-silica onyx, silicified wood, howlite, serpentinite, marble onyx, and kyanite. This paper aims to present an overview of Serbian gemstone deposits and occurrences and their position based on a simplified gemstone metallogenic map of Serbia, as well as genetic-industrial classification of gemstone deposits and gemstone varieties.

  14. Uranium deposits in Africa

    International Nuclear Information System (INIS)

    Wilpolt, R.H.; Simov, S.D.

    1979-01-01

    Africa is not only known for its spectacular diamond, gold, copper, chromium, platinum and phosphorus deposits but also for its uranium deposits. At least two uranium provinces can be distinguished - the southern, with the equatorial sub-province; and the south Saharan province. Uranium deposits are distributed either in cratons or in mobile belts, the first of sandstone and quartz-pebble conglomerate type, while those located in mobile belts are predominantly of vein and similar (disseminated) type. Uranium deposits occur within Precambrian rocks or in younger platform sediments, but close to the exposed Precambrian basement. The Proterozoic host rocks consist of sediments, metamorphics or granitoids. In contrast to Phanerozoic continental uranium-bearing sediments, those in the Precambrian are in marginal marine facies but they do contain organic material. The geology of Africa is briefly reviewed with the emphasis on those features which might control the distribution of uranium. The evolution of the African Platform is considered as a progressive reduction of its craton area which has been affected by three major Precambrian tectonic events. A short survey on the geology of known uranium deposits is made. However, some deposits and occurrences for which little published material is available are treated in more detail. (author)

  15. Gemstone deposits of Serbia

    Science.gov (United States)

    Miladinović, Zoran; Simić, Vladimir; Jelenković, Rade; Ilić, Miloje

    2016-06-01

    Gemstone minerals in Serbia have never been regarded as an interesting and significant resource. Nevertheless, more than 150 deposits and occurrences have been recorded and some of them preliminarily explored in the last 50 years. The majority of deposits and occurrences are located within the Serbo-Macedonian metallogenic province and the most significant metallogenic units at the existing level of knowledge are the Fruska Gora ore district, Cer ore district, Sumadija metallogenic zone, Kopaonik metallogenic zone and Lece-Halkidiki metallogenic zone. The most important genetic type of deposits is hydrothermal, particularly in case of serpentinite/peridotite as host/parent rock. Placer deposits are also economically important. The dominant gemstones are silica minerals: chalcedony (Chrysoprase, carnelian, bluish chalcedony etc.), jasper (picture, landscape, red etc.), common opal (dendritic, green, milky white etc.), silica masses (undivided), and quartz (rock crystal, amethyst etc.). Beside silica minerals significant gemstones in Serbia include also beryl (aquamarine), garnet (almandine and pyrope), tourmaline, fluorite, rhodochrosite, carbonate-silica breccia, carbonate-silica onyx, silicified wood, howlite, serpentinite, marble onyx, and kyanite. This paper aims to present an overview of Serbian gemstone deposits and occurrences and their position based on a simplified gemstone metallogenic map of Serbia, as well as genetic-industrial classification of gemstone deposits and gemstone varieties.

  16. Deposition and early hydrologic evolution of Westwater Canyon wet alluvial-fan system

    International Nuclear Information System (INIS)

    Galloway, W.E.

    1980-01-01

    The Westwater Canyon Member is one of several large, low-gradient alluvial fans that compose the Morrison Formation in the Four Corners area. Morrison fans were deposited by major laterally migrating streams entering a broad basin bounded by highlands to the west and south. The Westwater Canyon sand framework consists of a downfan succession of 1) proximal braided channel, 2) straight bed-load channel, 3) sinuous mixed-load channel, and 4) distributary mixed-load-channel sand bodies. Regional sand distribution and facies patterns are highly digitate and radiate from a point source located northwest of Gallup, New Mexico. Early ground-water flow evolution within the Westwater Canyon fan aquifer system can be inferred by analogy with Quaternary wet-fan deposits and by the interpreted paragenetic sequence of diagenetic features present. Syndepositional flow was controlled by the downfan hydrodynamic gradient and the high horizontal and vertical transmissivity of the sand-rich fan aquifer. Dissolution and transport of soluble humate would be likely in earliest ground water, which was abundant, fresh, and slightly alkaline. With increasing confinement of the aquifer below less permeable tuffaceous Brushy Basin deposits and release of soluble constituents from volcanic ash, flow patterns stabilized, and relatively more saline, uranium-rich ground water permeated the aquifer. Uranium mineralization occurred during this early postdepositional, semiconfined flow phase. Development of overlying Dakota swamps suggests a shallow water table indicative of regional dischare or stagnation. In either event, only limited downward flux of acidic water is recorded by local, bleached, kaolinized zones where the Westwater Canyon directly underlies the Dakota swamps. Subsequent ground-water flow phases have further obscured primary alteration patterns and caused local oxidation and redistribution of uranium

  17. Vein type uranium deposits

    International Nuclear Information System (INIS)

    1986-01-01

    Veins are tabular- or sheet-like masses of minerals occupying or following a fracture or a set of fractures in the enclosing rock. They have been formed later than the country rock and fractures, either by filling of the open spaces or by partial or complete replacement of the adjoining rock or most commonly by both of these processes combined. This volume begins with the occurrences and deposits known from old shield areas and the sedimentary belts surrounding them. They are followed by papers describing the European deposits mostly of Variscan age, and by similar deposits known from China being of Jurassic age. The volume is completed by two papers which do not fit exactly in the given scheme. A separate abstract was prepared for each of the 25 papers in this report

  18. Optical thin film deposition

    International Nuclear Information System (INIS)

    Macleod, H.A.

    1979-01-01

    The potential usefulness in the production of optical thin-film coatings of some of the processes for thin film deposition which can be classified under the heading of ion-assisted techniques is examined. Thermal evaporation is the process which is virtually universally used for this purpose and which has been developed to a stage where performance is in almost all respects high. Areas where further improvements would be of value, and the possibility that ion-assisted deposition might lead to such improvements, are discussed. (author)

  19. Radionuclide deposition control

    International Nuclear Information System (INIS)

    1980-01-01

    A method is described for controlling the deposition, on to the surfaces of reactor components, of the radionuclides manganese-54, cobalt-58 and cobalt-60 from a liquid stream containing the radionuclides. The method consists of disposing a getter material (nickel) in the liquid stream, and a non-getter material (tantalum, tungsten or molybdenum) as a coating on the surfaces where deposition is not desired. The process is described with special reference to its use in the coolant circuit in sodium cooled fast breeder reactors. (U.K.)

  20. Deposition potential of polonium

    Energy Technology Data Exchange (ETDEWEB)

    Heal, H. G.

    1948-11-23

    The cathodic deposition potential for polonium in concentrations of 10{sup -13} normal and 8 x 10{sup -13} normal, the former being 100-fold smaller than the smallest concentrations previously studied, has been determined. The value is 0.64 volt on the hydrogen scale. Considering the various ways in which the graphs can reasonably be drawn, we consider the maximum possible error to be of the order of +- 0.03 volt. There is apparently no shift of deposition potential between concentrations of 10{sup -8} and 10{sup -13} normal, indicating that the Nernst equation is not applicable in these circumstances.

  1. Reactive polymer fused deposition manufacturing

    Science.gov (United States)

    Kunc, Vlastimil; Rios, Orlando; Love, Lonnie J.; Duty, Chad E.; Johs, Alexander

    2017-05-16

    Methods and compositions for additive manufacturing that include reactive or thermosetting polymers, such as urethanes and epoxies. The polymers are melted, partially cross-linked prior to the depositing, deposited to form a component object, solidified, and fully cross-linked. These polymers form networks of chemical bonds that span the deposited layers. Application of a directional electromagnetic field can be applied to aromatic polymers after deposition to align the polymers for improved bonding between the deposited layers.

  2. Deposition Velocities of Non-Newtonian Slurries in Pipelines: Complex Simulant Testing

    Energy Technology Data Exchange (ETDEWEB)

    Poloski, Adam P.; Bonebrake, Michael L.; Casella, Andrew M.; Johnson, Michael D.; Toth, James J.; Adkins, Harold E.; Chun, Jaehun; Denslow, Kayte M.; Luna, Maria; Tingey, Joel M.

    2009-07-01

    One of the concerns expressed by the External Flowsheet Review Team (EFRT) is about the potential for pipe plugging at the Waste Treatment and Immobilization Plant (WTP). Per the review’s executive summary, “Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.” To evaluate the potential for plugging, deposition-velocity tests were performed on several physical simulants to determine whether the design approach is conservative. Deposition velocity is defined as the velocity below which particles begin to deposit to form a moving bed of particles on the bottom of a straight horizontal pipe during slurry-transport operations. The deposition velocity depends on the system geometry and the physical properties of the particles and fluid. An experimental program was implemented to test the stability-map concepts presented in WTP-RPT-175 Rev. 01. Two types of simulant were tested. The first type of simulant was similar to the glass-bead simulants discussed in WTP-RPT-175 Rev. 0 ; it consists of glass beads with a nominal particle size of 150 µm in a kaolin/water slurry. The initial simulant was prepared at a target yield stress of approximately 30 Pa. The yield stress was then reduced, stepwise, via dilution or rheological modifiers, ultimately to a level of <1 Pa. At each yield-stress step, deposition-velocity testing was performed. Testing over this range of yield-stress bounds the expected rheological operating window of the WTP and allows the results to be compared to stability-map predictions for this system. The second simulant was a precipitated hydroxide that simulates HLW pretreated sludge from Hanford waste tank AZ-101. Testing was performed in a manner similar to that for the first simulant over a wide range of yield stresses; however, an additional test of net-positive suction-head required (NPSHR

  3. Ion Deposited Carbon Coatings.

    Science.gov (United States)

    1983-07-01

    PAGE ("’hen Dita t,,I,, efl TABLE OF CONTENTS Section No. Title Page No. 1.0 OBJECTIVE 1 2.0 SCOPE 2 3.0 BACKGROUND 3 4.0 COATINGS DEPOSITION 4 4.1...scientific, ards of measure. The Committee, and Confer- technical, practical, and teaching purposes.ence voting members, are leading professional On the

  4. Plasma deposition of refractories

    International Nuclear Information System (INIS)

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

    1981-01-01

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

  5. 75 FR 34533 - Deposits

    Science.gov (United States)

    2010-06-17

    ... collection request (ICR) described below has been submitted to the Office of Management and Budget (OMB) for..., Attention: Desk Officer for OTS, U.S. Office of Management and Budget, 725 17th Street, NW., Room 10235... statement the institution sends to the consumer. Regulation DD contains rules for advertisements of deposit...

  6. Deposition Uniformity of Coal Dust on Filters and Its Effect on the Accuracy of FTIR Analyses for Silica.

    Science.gov (United States)

    Miller, Arthur L; Drake, Pamela L; Murphy, Nathaniel C; Cauda, Emanuele G; LeBouf, Ryan F; Markevicius, Gediminas

    Miners are exposed to silica-bearing dust which can lead to silicosis, a potentially fatal lung disease. Currently, airborne silica is measured by collecting filter samples and sending them to a laboratory for analysis. Since this may take weeks, a field method is needed to inform decisions aimed at reducing exposures. This study investigates a field-portable Fourier transform infrared (FTIR) method for end-of-shift (EOS) measurement of silica on filter samples. Since the method entails localized analyses, spatial uniformity of dust deposition can affect accuracy and repeatability. The study, therefore, assesses the influence of radial deposition uniformity on the accuracy of the method. Using laboratory-generated Minusil and coal dusts and three different types of sampling systems, multiple sets of filter samples were prepared. All samples were collected in pairs to create parallel sets for training and validation. Silica was measured by FTIR at nine locations across the face of each filter and the data analyzed using a multiple regression analysis technique that compared various models for predicting silica mass on the filters using different numbers of "analysis shots." It was shown that deposition uniformity is independent of particle type (kaolin vs. silica), which suggests the role of aerodynamic separation is negligible. Results also reflected the correlation between the location and number of shots versus the predictive accuracy of the models. The coefficient of variation (CV) for the models when predicting mass of validation samples was 4%-51% depending on the number of points analyzed and the type of sampler used, which affected the uniformity of radial deposition on the filters. It was shown that using a single shot at the center of the filter yielded predictivity adequate for a field method, (93% return, CV approximately 15%) for samples collected with 3-piece cassettes.

  7. Systematic variations in sinter mineralogy, microtexture and diagenesis in modern siliceous hot springs: Clues for interpreting depositional conditions in ancient deposits

    Science.gov (United States)

    Mills, V. W.; Farmer, J. D.; Ruff, S. W.; Nunez, J.; Jahnke, L. L.

    2011-12-01

    The deposits of siliceous hydrothermal springs are known to capture and preserve a wide range of microbial fossil information. The recent discovery of hydrothermal silica at Home Plate, Columbia Hills, Mars has once again raised interest in the potential importance of ancient spring sinters as targets for future astrobiological mission to Mars. To create additional context information to support future in situ missions to Mars, we have documented systematic changes in the mineralogy and microtexture of modern siliceous hot spring deposits, observed along gradients in temperature, pH and flow velocity. Specific objectives are to: 1) identify chemical and physical factors that promote early diagenetic transformations of amorphous silica (opal-A), to progressively more ordered and crystalline phases (cristobalite, tridymite and quartz); 2) determine the composition and abundance of minor mineral phases, especially clays, in relationship to pH, temperature and paragenesis; and 3) to assess the usefulness of sinter mineralogy and microtexture in reconstructing the paleoenvironmental records preserved in ancient deposits. Study sites for acidic (pH 2-5) sinters included Nymph Creek, located in the Norris Geyser Basin of Yellowstone National Park (YNP). Active alkaline (pH 7-10) springs included Rabbit Creek, Steep Cone and Mound Spring located in the Lower Geyser Basin, YNP. Field measurements in active springs included pH, temperature and flow velocity, along with general microfacies assignments. To better constrain types and rates of silica diagenesis, the study also sampled older (Holocene-Pleistocene-aged) deposits. Laboratory analyses included X-ray powder diffraction (XRPD), thermal infrared spectroscopy (TIR) and thin section petrography for characterizing sinter microtextures and for placing mineral phases (identified by XRPD and TIR) into a time-ordered diagenetic framework. In analyzing the phyllosilicates present in sinters, we applied clay separation and

  8. 78 FR 56583 - Deposit Insurance Regulations; Definition of Insured Deposit

    Science.gov (United States)

    2013-09-13

    ... as a potential global deposit insurer, preserve confidence in the FDIC deposit insurance system, and... the United States.\\2\\ The FDIC generally pays out deposit insurance on the next business day after a... since 2001 and total approximately $1 trillion today. In many cases, these branches do not engage in...

  9. Uranium deposits of Zaire

    International Nuclear Information System (INIS)

    Kitmut, D.; Malu wa Kalenga

    1979-01-01

    Since April 1960, following the closing of the Shinkolobwe mine, the Republic of Zaire has ceased to be a producer of uranium. Nevertheless, Gecamines (Generale des carrieres et mines du Zaire), a wholly state-owned company, is continuing its research on uranium occurrences which have been discovered in its concession in the course of aerial radiometric prospecting. The most recent campaign was the one carried out in 1969 and 1972 by Hunting Company. On-the-ground verification of these shows has not yet resulted in the discovery of a workable deposit. There are other sectors cutting across Zaire which might well contain uranium deposits: this is true of the sedimentary phosphates of the region of Lower Zaire as well as of the frontier region between Zaire and the Central African Empire. However, no detailed exploration work has yet been carried out. (author)

  10. 20 CFR 703.306 - Kinds of negotiable securities that may be deposited; conditions of deposit; acceptance of deposits.

    Science.gov (United States)

    2010-04-01

    ... the Act in the amount fixed by the Office under the regulations in this part shall deposit any... deposited; conditions of deposit; acceptance of deposits. 703.306 Section 703.306 Employees' Benefits... negotiable securities that may be deposited; conditions of deposit; acceptance of deposits. A self-insurer or...

  11. Thorium ore deposits

    International Nuclear Information System (INIS)

    Angelelli, Victorio.

    1984-01-01

    The main occurences of the thorium minerals of the Argentine Republic which have not been exploited, due to their reduced volume, are described. The thoriferous deposits have three genetic types: pegmatitic, hydrothermal and detritic, being the most common minerals: monazite, thorite and thorogummite. The most important thorium accumulations are located in Salta, being of less importance those of Cordoba, Jujuy and San Juan. (M.E.L.) [es

  12. Electrophoretic deposition of biomaterials

    Science.gov (United States)

    Boccaccini, A. R.; Keim, S.; Ma, R.; Li, Y.; Zhitomirsky, I.

    2010-01-01

    Electrophoretic deposition (EPD) is attracting increasing attention as an effective technique for the processing of biomaterials, specifically bioactive coatings and biomedical nanostructures. The well-known advantages of EPD for the production of a wide range of microstructures and nanostructures as well as unique and complex material combinations are being exploited, starting from well-dispersed suspensions of biomaterials in particulate form (microsized and nanoscale particles, nanotubes, nanoplatelets). EPD of biological entities such as enzymes, bacteria and cells is also being investigated. The review presents a comprehensive summary and discussion of relevant recent work on EPD describing the specific application of the technique in the processing of several biomaterials, focusing on (i) conventional bioactive (inorganic) coatings, e.g. hydroxyapatite or bioactive glass coatings on orthopaedic implants, and (ii) biomedical nanostructures, including biopolymer–ceramic nanocomposites, carbon nanotube coatings, tissue engineering scaffolds, deposition of proteins and other biological entities for sensors and advanced functional coatings. It is the intention to inform the reader on how EPD has become an important tool in advanced biomaterials processing, as a convenient alternative to conventional methods, and to present the potential of the technique to manipulate and control the deposition of a range of nanomaterials of interest in the biomedical and biotechnology fields. PMID:20504802

  13. Radionuclides deposition over Antarctica

    International Nuclear Information System (INIS)

    Pourchet, M.; Magand, O.; Frezzotti, M.; Ekaykin, A.; Winther, J.-G.

    2003-01-01

    A detailed and comprehensive map of the distribution patterns for both natural and artificial radionuclides over Antarctica has been established. This work integrates the results of several decades of international programs focusing on the analysis of natural and artificial radionuclides in snow and ice cores from this polar region. The mean value (37±20 Bq m -2 ) of 241 Pu total deposition over 28 stations is determined from the gamma emissions of its daughter 241 Am, presenting a long half-life (432.7 yrs). Detailed profiles and distributions of 241 Pu in ice cores make it possible to clearly distinguish between the atmospheric thermonuclear tests of the fifties and sixties. Strong relationships are also found between radionuclide data ( 137 Cs with respect to 241 Pu and 210 Pb with respect to 137 Cs), make it possible to estimate the total deposition or natural fluxes of these radionuclides. Total deposition of 137 Cs over Antarctica is estimated at 760 TBq, based on results from the 90-180 deg. East sector. Given the irregular distribution of sampling sites, more ice cores and snow samples must be analyzed in other sectors of Antarctica to check the validity of this figure

  14. Deposition and Resuspension of Particles

    DEFF Research Database (Denmark)

    Lengweiler, P.; Nielsen, Peter V.; Moser, A.

    A new experimental set-up to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airBorne dust concentration considerably. As a basis for developing methods to eliminate dust related problems in rooms......, there is a need for better understanding of the mechanism of dust deposition and resuspension....

  15. A Micrometeorological Perspective on Deposition

    DEFF Research Database (Denmark)

    Jensen, Niels Otto

    1981-01-01

    An expression for the dry deposition velocity is given in terms of constant flux layer scaling. Numerical values of upper bounds on the deposition velocity is given for a typical situation. Some remarks are then offered on the relative merits of various ways in which the combined diffusion-deposition...

  16. Market Discipline and Deposit Insurance

    OpenAIRE

    Peresetsky, Anatoly

    2008-01-01

    The paper examines Russian banks’ household deposit interest rates for the transition period of setting up the deposit insurance system. Monthly observations of Russian banks’ interest rates and balance sheets are used in a fixed effects panel data model. It is shown market discipline has been significantly diminished after switching to the deposit insurance.

  17. Potencialidades de um caulim calcinado como material de substituição parcial do cimento portland em argamassas Potentialities of a calcined kaolin as material of partial replacement of portland cement in mortars

    Directory of Open Access Journals (Sweden)

    Marilia P. de Oliveira

    2006-06-01

    Full Text Available A utilização de argilas calcinadas na forma de metacaulinita, como material pozolânico para argamassas e concretos, tem recebido atenção considerável nos últimos anos. Este trabalho objetivou avaliar o desempenho mecânico de argamassas, nas quais foi utilizado um caulim calcinado proveniente do Estado da Paraíba, como material de substituição parcial do cimento Portland. Utilizaram-se duas finuras do caulim: passando nas peneiras ABNT 200 (0,074 mm e 325 (0,044 mm e calcinados nas temperaturas de 700, 800 e 900 ºC pelo tempo de 2 h. As amostras foram caracterizadas através de análise química, análise térmica diferencial, difração de raios-X e área específica. Obteve-se o índice de atividade pozolânica com a cal e o cimento Portland. O percentual de substituição adotado foi de 0, 10, 20, 30 e 40%. A relação aglomerante: areia foi de 1:1,5 e a relação água/aglomerante fixada igual 0,4. O efeito da substituição parcial do cimento na argamassa foi avaliado através da resistência à compressão simples, nas idades de 7, 28 e 90 dias. As argamassas estudadas apresentaram resistência superior em relação à da referência, até o nível de 30% de substituição.The use of burnt clays, in the metakaolin form, as pozzolanic material for mortars and concretes has received a remarkable attention in the last years. This paper aimed to evaluate the mechanical property of mortars, in which a calcined kaolin originating from the State of Paraiba, was used as partial cement replacement material. Two finess of the kaolin were used: ABNT 200 (0.074 mm and 325 (0.044 mm and burnt at temperatures of 700, 800 and 900 ºC for a period of 2 h. Both materials were characterized by chemical analysis, differential thermal analysis, X-ray diffraction, specific area tests. The pozolanic activity index was obtanied using lime and cement Portland. The amounts of replacement were 10, 20, 30 and 40%, besides the reference mortar. The binder

  18. Elma Bahçelerinde Bazı Önemli Zararlılara Karşı Azadirachtin ve Kaolin Uygulamalarının Etkisi

    Directory of Open Access Journals (Sweden)

    Nazım KÜÇÜKBALLI

    2018-02-01

    Full Text Available Elma bahçelerinde ekonomik kayıplara neden olan birçok hastalık, zararlı ve yabancıot türü bulunmaktadır. Zararlılar içinde elma içkurdu, kırmızıörümcekler ve yaprakbitleri ana zararlılar arasında yer almaktadır. Elma üretiminin yoğun yapıldığı Isparta ilinde özellikle yağışlı geçen yıllarda yılda 20 kezden daha fazla ilaçlama yapıldığı bilinmektedir. Bu çalışmada söz konusu zararlılara karşı çevre ve yararlılara fazla etkisi olmadığı bilinen azadirachtin ve kaolinin etkisi 2015 yılında incelenmiştir. Denemeler Süleyman Demirel Üniversitesi, Ziraat Fakültesi bünyesinde bulunan 5 ve 2 dekarlık iki elma bahçesinde yürütülmüştür. Her bahçe dört parsele ayrılmış ve her bir parsele kaolin, azadirachtin (neem, karşılaştırma ilacı olarak chlorpyrifos-ethyl ve Kontrol parseline de su püskürtme şeklinde uygulanmıştır. Denemeler tesadüf blokları deneme desenine göre kurulmuş olup, her tekerrürde 8 ağaç olacak şekilde 6 tekerrürlü olarak düzenlenmiştir. Her hafta, her bir ağaçtan 40 yaprak örneği alınarak Tetranychus urticae, Pananychus ulmi, Aphis pomi ve Dysaphis plantaginea sayımları yapılmıştır. Elma içkurdu zararı ise hasat zamanında ağaç üzerinde ve yere düşen meyvelerde bulaşma oranına göre belirlenmiştir. Çalışma sonucunda yaprakbitine karşı en etkili Chlorpyrifos-ethyl bulunmuş, bunu kaolin ve neem izlemiştir. Preparatlar kırmızıörümceklere karşı benzer etki gösterirken elma içkurdu bulaşma oranları sırasıyla, kontrol parselinde %49.99, kaolin parselinde %42.27, neem parselinde %41.20 ve chlorpyrifos-ethyl parselinde %31.23 olmuştur.

  19. Electrophoretic Deposition of Gallium with High Deposition Rate

    Directory of Open Access Journals (Sweden)

    Hanfei Zhang

    2014-12-01

    Full Text Available In this work, electrophoretic deposition (EPD is reported to form gallium thin film with high deposition rate and low cost while avoiding the highly toxic chemicals typically used in electroplating. A maximum deposition rate of ~0.6 μm/min, almost one order of magnitude higher than the typical value reported for electroplating, is obtained when employing a set of proper deposition parameters. The thickness of the film is shown to increase with deposition time when sequential deposition is employed. The concentration of Mg(NO32, the charging salt, is also found to be a critical factor to control the deposition rate. Various gallium micropatterns are obtained by masking the substrate during the process, demonstrating process compatibility with microfabrication. The reported novel approach can potentially be employed in a broad range of applications with Ga as a raw material, including microelectronics, photovoltaic cells, and flexible liquid metal microelectrodes.

  20. Dry deposition on urban surfaces

    International Nuclear Information System (INIS)

    Roed, J.

    1985-01-01

    In order to facilitate developing a model for deposition in urban areas, beryllium-7, created by cosmic radiation and fall-out cesium-137, have been used as tracers in measurements designed to find the dry deposition velocity on building surfaces. A literature review has revealed that very little work has been done on deposition in urban areas; therefore, a major effort on meausring the deposition parameter is needed to construct reliable models in this field. Deposition velocities in the range from 0.001-0.04 cm/s have been found. (author)

  1. Thermal plasma chemical vapor deposition

    International Nuclear Information System (INIS)

    Heberlein, J.; Pfender, E.

    1993-01-01

    Thermal plasmas, with temperatures up to and even exceeding 10 4 K, are capable of producing high density vapor phase precursors for the deposition of relatively thick films. Although this technology is still in its infancy, it will fill the void between the relatively slow deposition processes such as physical vapor deposition and the high rate thermal spray deposition processes. In this chapter, the present state-of-the-art of this field is reviewed with emphasis on the various types of reactors proposed for this emerging technology. Only applications which attracted particular attention, namely diamond and high T c superconducting film deposition, are discussed in greater detail. (orig.)

  2. Uranium ore deposits

    International Nuclear Information System (INIS)

    Angelelli, Victorio.

    1984-01-01

    The main uranium deposits and occurrences in the Argentine Republic are described, considering, in principle, their geologic setting, the kind of 'model' of the mineralization and its possible origin, and describing the ore species present in each case. The main uraniferous accumulations of the country include the models of 'sandstong type', veintype and impregnation type. There are also other kinds of accumulations, as in calcrete, etc. The main uranium production has been registered in the provinces of Mendoza, Salta, La Rioja, Chubut, Cordoba and San Luis. In each case, the minerals present are mentioned, having been recognized 37 different species all over the country (M.E.L.) [es

  3. Deposition of carbon dioxide

    International Nuclear Information System (INIS)

    2001-01-01

    In Norway, there is currently a debate about whether or not to build gas power stations. To meet the possibility of reduced emission quotas for carbon dioxide in the future, current interest focuses on the incorporation of large-scale separation and deposition of carbon dioxide when such plants are planned. A group of experts concludes that this technology will become self-financing by means of environmental taxes. From the environmental point of view, taxes upon production are to be preferred over taxes on consumption

  4. Stratigraphic implications of uranium deposits

    International Nuclear Information System (INIS)

    Langford, F.F.

    1980-01-01

    One of the most consistent characteristics of economic uranium deposits is their restricted stratigraphic distribution. Uraninite deposited with direct igneous affiliation contains thorium, whereas chemical precipitates in sedimentary rocks are characterized by thorium-free primary uranium minerals with vanadium and selenium. In marine sediments, these minerals form low-grade disseminations; but in terrestrial sediments, chiefly fluvial sandstones, the concentration of uranium varies widely, with the high-grade portions constituting ore. Pitchblende vein deposits not only exhibit the same chemical characteristics as the Colorado-type sandstone deposits, but they have a stratigraphically consistent position at unconformities covered by fluvial sandstones. If deposits in such diverse situations have critical features in common, they are likely to have had many features of their origin in common. Thus, vein deposits in Saskatchewan and Australia may have analogues in areas that contain Colorado-type sandstone deposits. In New Mexico, the presence of continental sandstones with peneconformable uranium deposits should also indicate good prospecting ground for unconformity-type vein deposits. All unconformities within the periods of continental deposition ranging from Permian to Cretaceous should have uranium potential. Some situations, such as the onlap of the Abo Formation onto Precambrian basement in the Zuni Mountains, may be directly comparable to Saskatchewan deposition. However, uranium occurrences in the upper part of the Entrada Sandstone suggest that unconformities underlain by sedimentary rocks may also be exploration targets

  5. Sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    Austin, S.R.; D'Andrea, R.F. Jr.

    1978-01-01

    Three overall factors are necessary for formation of uranium deposits in sandstone: a source of uranium, host rocks capable of transmitting uranium-bearing solutions, and a precipitant. Possible sources of uranium in sandstone-type deposits include groundwaters emanating from granitic highlands, arkosic sediments, tuffaceous material within or overlying the host rocks, connate fluids, and overlying black shales. The first three sources are considered the most likely. Host rocks are generally immature sandstones deposited in alluvial-fan, intermontane-basin or marginal-marine environments, but uranium deposits do occur in well-winnowed barrier-bar or eolian sands. Host rocks for uranium deposits generally show coefficients of permeability on the order of 1 to 100 gal/day/ft 2 . Precipitants are normally agents capable of reducing uranium from the uranyl to the uranous state. The association of uranium with organic matter is unequivocal; H 2 S, a powerful reductant, may have been present at the time of formation of some deposits but may go unnoticed today. Vanadium can serve to preserve the tabular characteristics of some deposits in the near-surface environment, but is considered an unlikely primary precipitant for uranium. Uranium deposits in sandstone are divided into two overall types: peneconcordant deposits, which occur in locally reducing environments in otherwise oxidized sandstones; and roll-type deposits, which occur at the margin of an area where an oxidized groundwater has permeated an otherwise reduced sandstone. Uranium deposits are further broken down into four subclasses; these are described

  6. Geological factors of deposit formation

    International Nuclear Information System (INIS)

    Grushevoj, G.V.

    1980-01-01

    Geologic factors of hydrogenic uranium deposit formation are considered. Structural, formation and lithological-facies factors of deposit formation, connected with zones of stratal oxidation, are characterized. Peculiarities of deposit localization, connected with orogenic structures of Mesozoic and lenozoic age, are described. It is noted that deposits of anagenous group are widely spread in Paleozoic formations, infiltration uranium deposits are localized mainly in Cenozoic sediments, while uranium mineralization both anagenous and infiltration groups are widely developed in Mesozoic sediments. Anagenous deposits were formed in non-oxygen situation, their age varies from 200 to 55 mln years. Infiltration deposit formation is determined by asymmetric oxidation zonation, their age varies from 10 - 40 mln years to dozens of thousand years [ru

  7. Características físicas dos minérios de caulim das minas floresta, Cavalheiro, Turvo e Kowalski, em Campo Alegre (SC, e de Trigolândia (PR Physical characteristics of kaolin ores from Floresta, Cavalheiro, Turvo and Kowalski Mines (SC and from Trigolândia Mine (PR

    Directory of Open Access Journals (Sweden)

    J. C. Biondiv

    2000-06-01

    of these values are shown on tables and graphics. Those determinations and field observations allow to the conclusion that kaolin deposits are of two different types, named Trigolândia model, originated from pegmatites, and Floresta model, derived from acid volcanic rocks. With the exception of the ore from Turvo Mine, the average values of the analyzed physical properties are always into the intervals accepted by Oxford industrial processes, that runs to produce tableware. From Turvo Mine, the green and the brown ores have the more discordant characteristics. For the other ores, from Turvo and the other mines, the average values of their physical characteristics almost always equal the central values of intervals that characterize good ores. If correlations between average values of different physical properties of ores are made, only Trigolândia shows some bad correlations. Taking into account all the analyzed values, and no more the averages, all the correlations are bad. The exception is the correlation between dry retraction and fired retraction, with r = 0,78. All other correlation coefficients are lower than 0,60.

  8. FDIC Summary of Deposits (SOD) Download File

    Data.gov (United States)

    Federal Deposit Insurance Corporation — The FDIC's Summary of Deposits (SOD) download file contains deposit data for branches and offices of all FDIC-insured institutions. The Federal Deposit Insurance...

  9. Preparação e caracterização de materiais compósitos SiC/caulim/Al via "squeeze-casting" Preparation and characterization of SiC/kaolin/Al composite materials by squeeze- casting

    Directory of Open Access Journals (Sweden)

    M. Freitas

    2009-09-01

    manufacturing these composites is the process of metal casting infiltration under pressure called squeeze-casting. This process offers some advantages, such as ease of producing the composite, low cost and ability to form network structures. In this work were produced and characterized Al-SiC composites, with concentrations in kaolin ranging between 10 and 50% in place to SiC majority phase. The ceramic pre-forms were produced to controlling the fraction of the size SiC/kaolin for better infiltration. These pre-forms after sintering at 1100 ºC/1 h resulted highly porous, and the porosity increased with the increase of kaolin in place to SiC particles. XRD analysis showed the existence of quartz particles beyond the SiC phase. During the infiltration and heat treatment process, the liquid aluminum reacted preferably with quartz and other aluminosilicates particles of the pre-form reducing them, precipitating alumina and silicon in the microstructure, which also presented aluminum in excess that not reacted in the process. The silica and silicates of pre-form, reacted preferably with the aluminum, preventing the formation of Al4C3 phase, which is highly hygroscopic and causes the composite degradation. Depending on the composition, the SiC - kaolin - Al composite developed in this work, can be used in applications involving high bending mechanical resistance (240 to 300 MPa, low density and hardness surface between 180 and 380 kgf/mm².

  10. Sensitivity of the activated partial thromboplastin time, the dilute Russell's viper venom time, and the kaolin clotting time for the detection of the lupus anticoagulant: a direct comparison using plasma dilutions.

    Science.gov (United States)

    Martin, B A; Branch, D W; Rodgers, G M

    1996-01-01

    Increasing dilutions of lupus anticoagulant (LA) plasmas from twelve patients were used to directly compare the sensitivity of four tests for LA. The tests evaluated were the modified Bell and Alton activated partial thromboplastin time (APTT), an APTT using a commercially prepared partial thromboplastin (Platelin LS APTT), a modified dilute Russell's viper venom time (DRVVT), and a modified kaolin clotting time (KCT). LAs were detected in all twelve plasmas by each of three tests and eleven of twelve plasmas in a fourth test when undiluted patient plasma was used. Repeating the tests after diluting the LA plasmas with normal platelet-free plasma (PFP) showed that the KCT was the most sensitive test for LA, detecting eleven of twelve LAs at a dilution of 10% patient plasma and ten of twelve LAs at a dilution of 5% patient plasma. The modified Bell and Alton APTT and the modified DRVVT had similar sensitivities at a patient plasma concentration of 10%, detecting seven of twelve and eight of twelve LAs, respectively. The Platelin LS APTT detected only four of twelve LAs at a patient plasma concentration of 10%. Our results indicate that the modified KCT is a sensitive method for the detection of LAs. The modified Bell and Alton APTT and the DRVVT were less sensitive.

  11. Plutonium in uranium deposits

    International Nuclear Information System (INIS)

    Curtis, D.; Fabryka-Martin, J.; Aguilar, R.; Attrep, M. Jr.; Roensch, F.

    1992-01-01

    Plutonium-239 (t 1/2 , 24,100 yr) is one of the most persistent radioactive constituents of high-level wastes from nuclear fission power reactors. Effective containment of such a long-lived constituent will rely heavily upon its containment by the geologic environment of a repository. Uranium ore deposits offer a means to evaluate the geochemical properties of plutonium under natural conditions. In this paper, analyses of natural plutonium in several ores are compared to calculated plutonium production rates in order to evaluate the degree of retention of plutonium by the ore. The authors find that current methods for estimating production rates are neither sufficiently accurate nor precise to provide unambiguous measures of plutonium retention. However, alternative methods for evaluating plutonium mobility are being investigated, including its measurement in natural ground waters. Preliminary results are reported and establish the foundation for a comprehensive characterization of plutonium geochemistry in other natural environments

  12. Classification of Uranium deposits

    International Nuclear Information System (INIS)

    Dahlkamp, F.J.

    1978-01-01

    A listing of the recognized types of uranium mineralization shows nineteen determinable types out of which only six can be classified as of economic significance at present: Oligomiitic quartz pebble conglomerates, sandstone types, calcretes, intra-intrusive types, hydrothermal veins, veinlike types. The different types can be genetically related to prevalent geological environments, i.e. 1. the primary uranium occurrences formed by endogenic processes, 2. the secondary derived from the primary by subsequent exogenic processes, 3. the tertiary occurrences are assumed to be formed by endogenic metamorphic processes, although little is known about the behaviour of the uranium during the metamorphosis and therefore the metallogenesis of this tertiary uranium generation is still vague. A metallotectonic-geochronologic correlation of the uranium deposits shows a distinct affinity of the uranium to certain geological epochs: The Upper Archean, Lower Proterozoic, the Hercynian and, in a less established stage, the Upper Proterozoic. (orig.) 891 HP/orig. 892 MKO [de

  13. Locating underground uranium deposits

    International Nuclear Information System (INIS)

    Felice, P.E.

    1979-01-01

    Underground uranium deposits are located by placing wires of dosimeters each about 5 to 18 mg/cm 2 thick underground in a grid pattern. Each dosimeter contains a phosphor which is capable of storing the energy of alpha particles. In each pair one dosimeter is shielded from alpha particles with more than 18 mg/cm 2 thick opaque material but not gamma and beta rays and the other dosimeter is shielded with less than 1 mg/cm 2 thick opaque material to exclude dust. After a period underground the dosimeters are heated which releases the stored energy as light. The amount of light produced from the heavily shielded dosimeter is subtracted from the amount of light produced from the thinly shielded dosimeter to give an indication of the location and quantity of uranium underground

  14. Global deposition of airborne dioxin.

    Science.gov (United States)

    Booth, Shawn; Hui, Joe; Alojado, Zoraida; Lam, Vicky; Cheung, William; Zeller, Dirk; Steyn, Douw; Pauly, Daniel

    2013-10-15

    We present a global dioxin model that simulates one year of atmospheric emissions, transport processes, and depositions to the earth's terrestrial and marine habitats. We map starting emission levels for each land area, and we also map the resulting deposits to terrestrial and marine environments. This model confirms that 'hot spots' of deposition are likely to be in northern Europe, eastern North America, and in parts of Asia with the highest marine dioxin depositions being the northeast and northwest Atlantic, western Pacific, northern Indian Ocean and the Mediterranean. It also reveals that approximately 40% of airborne dioxin emissions are deposited to marine environments and that many countries in Africa receive more dioxin than they produce, which results in these countries being disproportionately impacted. Since human exposure to dioxin is largely through diet, this work highlights food producing areas that receive higher atmospheric deposits of dioxin than others. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A remote coal deposit revisited

    DEFF Research Database (Denmark)

    Bojesen-Kofoed, Jørgen A.; Kalkreuth, Wolfgang; Petersen, Henrik I.

    2012-01-01

    discovery. The outcrops found in 2009 amount to approximately 8 m of sediment including a coal seam of 2 m thickness. More outcrops and additional coal deposits most certainly are to be found, pending further fieldwork. The deposits are Middle Jurassic, Callovian, in age and were deposited in a floodplain...... environment related to meandering river channels. Spores and pollen in the lower fluvial deposits reflect abundant vegetation of ferns along the river banks. In contrast, a sparse spore and pollen flora in the coals show a mixed vegetation of ferns and gymnosperms. Based on proximate and petrographic analyses...

  16. 76 FR 41392 - Interest on Deposits; Deposit Insurance Coverage

    Science.gov (United States)

    2011-07-14

    ... banks' funding costs and also allow them to plan business growth more dependably and rigorously... of business deposits by offering continually higher rates of interest. Three of the four contended... deposits. They reasoned that large banks will offer high rates of interest and lure away business...

  17. Sedimentological and Scanning Electron Miscroscopic Descriptions of Afowo Oil Sand Deposits, South Western Nigeria

    Directory of Open Access Journals (Sweden)

    Akinmosin A

    2017-12-01

    Full Text Available Sedimentological and scanning electron microscopic analyses of some shallow reservoir tar sand samples in parts of Southwestern Nigeria were carried out with the aim of characterizing the reservoir properties in relation to bitumen saturation and recovery efficiency. The production of impregnated tar from the sands requires the reservoir to be of good quality. A total of thirty samples were collected at different localities within the tar sand belt (ten out of these samples were selected for various reservoir quality analyses based on their textural homogeneity. The result of particle size distribution study showed that bulk of the sands is medium – coarse grained and moderately sorted. The grain morphologies are of low to high sphericity with shapes generally sub-angular to sub-rounded, implying that the sands have undergone a fairly long transportation history with depositional energy having a moderate to high velocity. The quartz content was made up of about 96% of the total mineralogical components; the sediments of the Afowo Formation can be described to be mineralogically and texturally stable. The result of the scanning electron microscopy (SEM analysis revealed that the oil sands contained minerals which had been precipitated and occurred as pore filling cement; these minerals include sheet kaolinite, block kaolinite, vermiform kaolinite, pyrite crystals and quartz. The SEM images also showed micro-pores ranging from 0.057µm to 0.446µm and fractures. The study showed that the clay minerals contained in the Afowo reservoir rocks were mainly kaolinite. Kaoline unlike some other clays (e.g Montimorillonite does not swell with water, hence it is not expected to have any negative effects on the reservoir quality, especially during enhanced oil recovery operations.

  18. Viabilidade do uso de argilas cauliníticas do Quadrilátero Ferrífero para a indústria cerâmica Availability of the kaolin from Quadrilátero Ferrífero for the ceramic industry

    Directory of Open Access Journals (Sweden)

    M. G. Peralta-Sánchez

    2011-09-01

    Full Text Available Sete amostras compostas, representativas de três ocorrências de argila caulinítica do Quadrilátero Ferrífero, foram caracterizadas física, mineralógica e quimicamente visando seu uso na indústria cerâmica. Apesar da presença predominante de caulinita, variações nos teores de Fe2O3 entre 2 a 44%, refletidos pela presença de goethita e hematita, acarretam diferentes cores que variam entre branco (ACM e DB, amarelo (R5, vermelho amarelado (FS e vermelho (DV, R1 e AM. Corpos cerâmicos foram queimados a 900 e 1100 °C, sendo que as cores praticamente não mudaram após a queima. Entretanto, somente corpos feitos com DV e R1 cumpriram as especificações técnicas para cerâmica, não apresentando fraturas e atingindo altas resistências à compressão: 96,2 MPa e 64,2 MPa, respectivamente. Para as outras amostras foram testadas misturas com filito (F nas proporções de 5, 10, 15, 20 e 25% e queima a 900 e 1100 °C. Os melhores resultados dos corpos cerâmicos, com ausência de fraturas, resistências à compressão entre 69,15 e 29,6 MPa e que cumpriram as especificações técnicas, foram obtidos nas proporções: ACM+15F, DB+5F, R5+5F, FS+5F, AM+5F e queima a 900 ºC.Seven samples from three kaolin deposits of the Quadrilátero Ferrífero were characterized by physical, mineralogical and chemical analyses in order to determine their use in the ceramic industry. Despite the predominant presence of kaolinite, the variations in the Fe2O3 content from 2 to 44%, due to presence of goethite and hematite, resulted in different colors, namely: white (ACM and DB, yellow (R5, yellowed red (FS and red (DV, R1 and AM. Specimens were burned at 900 and 1100 °C and they almost didn't change color. However, only specimens made with DV and R1 samples reached the technical specifications for the ceramic industry, without fractures and with values of compression strength of 96.2 and 64.2 MPa, respectively. The other samples were made by mixing

  19. Uranium deposits in granitic rocks

    International Nuclear Information System (INIS)

    Nishimori, R.K.; Ragland, P.C.; Rogers, J.J.W.; Greenberg, J.K.

    1977-01-01

    This report is a review of published data bearing on the geology and origin of uranium deposits in granitic, pegmatitic and migmatitic rocks with the aim of assisting in the development of predictive criteria for the search for similar deposits in the U.S. Efforts were concentrated on the so-called ''porphyry'' uranium deposits. Two types of uranium deposits are primarily considered: deposits in pegmatites and alaskites in gneiss terrains, and disseminations of uranium in high-level granites. In Chapter 1 of this report, the general data on the distribution of uranium in igneous and metamorphic rocks are reviewed. Chapter 2 contains some comments on the classification of uranium deposits associated with igneous rocks and a summary of the main features of the geology of uranium deposits in granites. General concepts of the behavior of uranium in granites during crustal evolution are reviewed in Chapter 3. Also included is a discussion of the relationship of uranium mineralization in granites to the general evolution of mobile belts, plus the influence of magmatic and post-magmatic processes on the distribution of uranium in igneous rocks and related ore deposits. Chapter 4 relates the results of experimental studies on the crystallization of granites to some of the geologic features of uranium deposits in pegmatites and alaskites in high-grade metamorphic terrains. Potential or favorable areas for igneous uranium deposits in the U.S.A. are delineated in Chapter 5. Data on the geology of specific uranium deposits in granitic rocks are contained in Appendix 1. A compilation of igneous rock formations containing greater than 10 ppM uranium is included in Appendix 2. Appendix 3 is a report on the results of a visit to the Roessing area. Appendix 4 is a report on a field excursion to eastern Canada

  20. Enhanced nitrogen deposition over China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xuejun; Zhang, Ying; Han, Wenxuan; Tang, Aohan; Shen, Jianlin; Cui, Zhenling; Christie, Peter; Zhang, Fusuo [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Vitousek, Peter [Department of Biology, Stanford University, Stanford, California 94305 (United States); Erisman, Jan Willem [VU University Amsterdam, 1081 HV Amsterdam (Netherlands); Goulding, Keith [The Sustainable Soils and Grassland Systems Department, Rothamsted Research, Harpenden AL5 2JQ (United Kingdom); Fangmeier, Andreas [Institute of Landscape and Plant Ecology, University of Hohenheim, 70593 Stuttgart (Germany)

    2013-02-28

    China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P < 0.001) between the 1980s (13.2 kilograms of nitrogen per hectare) and the 2000s (21.1 kilograms of nitrogen per hectare). Nitrogen deposition rates in the industrialized and agriculturally intensified regions of China are as high as the peak levels of deposition in northwestern Europe in the 1980s, before the introduction of mitigation measures. Nitrogen from ammonium (NH4+) is the dominant form of N in bulk deposition, but the rate of increase is largest for deposition of N from nitrate (NO3-), in agreement with decreased ratios of NH3 to NOx emissions since 1980. We also find that the impact of N deposition on Chinese ecosystems includes significantly increased plant foliar N concentrations in natural and semi-natural (that is, non-agricultural) ecosystems and increased crop N uptake from long-term-unfertilized croplands. China and other economies are facing a continuing challenge to reduce emissions of reactive nitrogen, N deposition and their negative effects on human health and the environment.

  1. Liquefier Dynamics in Fused Deposition

    DEFF Research Database (Denmark)

    Bellini, Anna; Guceri, Selcuk; Bertoldi, Maurizio

    2004-01-01

    Layered manufacturing (LM) is an evolution of rapid prototyping (RP) technology whereby a part is built in layers. Fused deposition modeling (FDM) is a particular LM technique in which each section is fabricated through vector style deposition of building blocks, called roads, which...

  2. NURE uranium deposit model studies

    International Nuclear Information System (INIS)

    Crew, M.E.

    1981-01-01

    The National Uranium Resource Evaluation (NURE) Program has sponsored uranium deposit model studies by Bendix Field Engineering Corporation (Bendix), the US Geological Survey (USGS), and numerous subcontractors. This paper deals only with models from the following six reports prepared by Samuel S. Adams and Associates: GJBX-1(81) - Geology and Recognition Criteria for Roll-Type Uranium Deposits in Continental Sandstones; GJBX-2(81) - Geology and Recognition Criteria for Uraniferous Humate Deposits, Grants Uranium Region, New Mexico; GJBX-3(81) - Geology and Recognition Criteria for Uranium Deposits of the Quartz-Pebble Conglomerate Type; GJBX-4(81) - Geology and Recognition Criteria for Sandstone Uranium Deposits in Mixed Fluvial-Shallow Marine Sedimentary Sequences, South Texas; GJBX-5(81) - Geology and Recognition Criteria for Veinlike Uranium Deposits of the Lower to Middle Proterozoic Unconformity and Strata-Related Types; GJBX-6(81) - Geology and Recognition Criteria for Sandstone Uranium Deposits of the Salt Wash Type, Colorado Plateau Province. A unique feature of these models is the development of recognition criteria in a systematic fashion, with a method for quantifying the various items. The recognition-criteria networks are used in this paper to illustrate the various types of deposits

  3. Sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    Finch, W.I.; Davis, J.F.

    1985-01-01

    World-class sandstone-type uranium deposits are defined as epigenetic concentrations of uranium minerals occurring as uneven impregnations and minor massive replacements primarily in fluvial, lacustrine, and deltaic sandstone formations. The main purpose of this introductory paper is to define, classify, and introduce to the general geologic setting for sandstone-type uranium deposits

  4. Laser deposition of HTSC films

    International Nuclear Information System (INIS)

    Sobol', Eh.N.; Bagratashvili, V.N.; Zherikhin, A.N.; Sviridov, A.P.

    1990-01-01

    Studies of the high-temperature superconducting (HTSC) films fabrication by the laser deposition are reviewed. Physical and chemical processes taking place during laser deposition are considered, such as the target evaporation, the material transport from the target to the substrate, the film growth on the substrate, thermochemical reactions and mass transfer within the HTSC films and their stability. The experimental results on the laser deposition of different HTSC ceramics and their properties investigations are given. The major technological issues are discussed including the deposition schemes, the oxygen supply, the target compositions and structure, the substrates and interface layers selection, the deposition regimes and their impact on the HTSC films properties. 169 refs.; 6 figs.; 2 tabs

  5. Polymer deposition morphology by electrospray deposition - Modifications through distance variation

    International Nuclear Information System (INIS)

    Altmann, K.; Schulze, R.-D.; Friedrich, J.

    2014-01-01

    Electrospray deposition (ESD) of highly diluted polymers was examined with regard to the deposited surface structure. Only the flight distance (flight time) onto the resulting deposited surface was varied from 20 to 200 mm. An apparatus without any additional heating or gas flows was used. Polyacrylic acid (PAA) and polyallylamine (PAAm) in methanol were deposited on Si wafers. The polymer layers were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, derivatization reactions and Fourier transform infrared spectroscopy using a grazing incidence unit. SEM images illustrated the changing structures of PAA and PAAm. For PAA the deposited structure changed from a smooth film (20 mm) to a film with individual droplets on the coated surface (100 mm and 200 mm), while for PAAm individual droplets can be seen at all distances. The ESD process with cascades of splitting droplets slows down for PAA after distances greater than 40 mm. In contrast, the ESD process for PAAm is nearly stopped within the first flight distance of 20 mm. Residual solvent analysis showed that most of the solvent evaporated within the first 20 mm capillary-sample distance. - Highlights: • We deposited polyacrylic acid and polyallylamine by electrospray ionization (ESI). • The morphology in dependence of flight distance (20 mm to 200 mm) was analyzed. • The amount of residual solvent after deposition was determined. • ESI-process slows down for polyacrylic acid after 40 mm flight distance. • ESI-Process is complete for polyallylamine within the first 20 mm

  6. 20 CFR 703.207 - Kinds of negotiable securities that may be deposited; conditions of deposit; acceptance of deposits.

    Science.gov (United States)

    2010-04-01

    ... amount fixed by the Office under the regulations in this part shall deposit any negotiable securities... deposited; conditions of deposit; acceptance of deposits. 703.207 Section 703.207 Employees' Benefits... AND RELATED STATUTES INSURANCE REGULATIONS Insurance Carrier Security Deposit Requirements § 703.207...

  7. Expansão por umidade de revestimentos cerâmicos incorporados com residuos de granito e caulim Moisture expansion of ceramic tiles produced using kaolin and granite wastes

    Directory of Open Access Journals (Sweden)

    A. M. G. D. Mendonça

    2012-06-01

    Full Text Available Expansão por umidade (EPU é o aumento das dimensões dos materiais cerâmicos em virtude da adsorção de água. A EPU geralmente ocorre lentamente e é relativamente pequena, mas, mesmo assim, pode comprometer a aderência das placas cerâmicas ao contrapiso, levar ao gretamento do vidrado e conduzir ao aparecimento de trincas em tijolos. Neste trabalho empregaram-se massas incorporadas com resíduos de caulim e de granito objetivando estudar a EPU de revestimentos cerâmicos. As matérias-primas foram beneficiadas e submetidas às caracterizações físicas e mineralógicas através de ensaios de análise granulométrica por difração a laser, análise química, análise termodiferencial, termogravimétrica e difração de raios X. Os resultados mostraram que os resíduos de caulim e de granito podem ser utilizados como matéria-prima cerâmica alternativa, pois apresentam características similares às matérias-primas cerâmicas convencionais, permitindo a obtenção de peças com resultados de EPU satisfatórios quando comparado ao valor limite de 0,6 mm/m (0,06% proposto pela ABNT para revestimentos cerâmicos, notadamente em composições com teores de até 20% de resíduos, a temperaturas superiores a 1000 ºC.Moisture expansion (ME is the term used to describe the expansion of ceramic materials due to the adsorption of water. ME usually occurs slowly and is relatively small, but, it can damage the ceramic tiles adhesion to the underlayment, craze the glaze and lead to the development of cracks on ceramics bricks. In this work kaolin and granite wastes were incorporated in ceramic compositions aiming study their influence on the ME of ceramic tiles. Raw materials were processed and submitted to characterization: physical and mineralogical by laser diffraction particle size analysis, chemical analysis, thermodifferential and thermogravimetric analysis and X-ray diffraction. Results showed that kaolin and granite wastes can be

  8. Mineralogical characterization and beneficiation study of kaolin from Equador (RN) and Junco do Serido (PB) to increase the brightness index; Caracterizacao mineralogica e estudo do beneficiamento do caulim de Equador (RN) e Junco do Serido (PB) para elevacao do indice de alvura

    Energy Technology Data Exchange (ETDEWEB)

    Campos, V.M.J.S.; Bertolino, L.C., E-mail: vcampos@cetem.gov.br, E-mail: lcbertolino@cetem.gov.br [Centro de Tecnologia Minearal (CETEM), Rio de Janeiro, RJ (Brazil). Setor de Caracterizacao Tecnologica; Alves, O.C., E-mail: odivaldocambraia@id.uff.br [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Quimica

    2017-07-15

    Kaolin is a rock composed mainly of kaolinite. It is used in many industrial segments, such as paper and ceramics. However, for these uses it is necessary to submit the ore to appropriate beneficiation, which generally involves magnetic separation and chemical bleaching, aiming to remove iron oxide and hydroxide, raising brightness index. This work reports the mineralogical characterization and analysis of the beneficiation of three samples of kaolin, two from Equador (Rio Grande do Norte - RN) and the third from Junco do Serido (Paraiba - PB). The samples were submitted to granulometric classification in sieve of 44 μm, magnetic separation in a magnetic induction of 14000 gauss, and chemical bleaching with sodium dithionite during 240 min. The processes were divided into two beneficiation routes. X-ray diffraction, chemical analysis by X-ray fluorescence and scanning electron microscopy were used for mineralogical characterization of the ore and measurement of the brightness index, while electron paramagnetic resonance was applied to study the variation of iron oxides and hydroxides during beneficiation. The results indicate that just 30 min of chemical bleaching without magnetic separation was sufficient to increase the brightness index from 78.2 to 90.2% and from 91.3 to 95.7% in the two samples from Equador (RN) and from 86.9 to 90.4% in the sample from Junco do Serido (PB). The magnetic separation, although causing a small increase in the brightness index, was inefficient for removal of iron oxides and hydroxides. The results indicated no need for using magnetic separation in plants for beneficiation of kaolin from these two locations, providing the reduction of production costs allowing better exploitation of the ore. (author)

  9. Surface deposition from radioactive plumes

    International Nuclear Information System (INIS)

    Garland, J.A.

    1980-01-01

    Accidents involving nuclear plants may release radioactive particles and gases to the atmosphere. Dry deposition of particles has been investigated mainly in the laboratory and a general understanding of the transfer mechanisms has been established. However there is apparently a substantial discrepancy between the few field observations of dry deposition of particles and laboratory measurements, particularly for 0.1 - 1 μm particles for which laboratory work shows very small deposition rates. In addition there are few estimates of deposition rates for forest and some other kinds of terrain. The most important gas in the context of a nuclear accident is I-131 and the behaviour of this gas at grass surfaces has received much attention. However smaller quantities of other gases and vapours may be released and the surface absorption of these species may require further investigation. In addition there is little knowledge of the behaviour of gases over many types of surface. The rate of deposition of particles and gases is influenced by many parameters including wind speed and the temperature stratification of the lower atmosphere. Conditions which give poor atmospheric dispersion usually give lower deposition velocities. Transfer to man depends on the availability of deposited materials on crops and grass. A wide range of isotopes including iodine and several metallic fission products are lost with a half life for residence on grass ranging from a few days to a few tens days, depending on climatic conditions

  10. ITO thin films deposited by advanced pulsed laser deposition

    International Nuclear Information System (INIS)

    Viespe, Cristian; Nicolae, Ionut; Sima, Cornelia; Grigoriu, Constantin; Medianu, Rares

    2007-01-01

    Indium tin oxide thin films were deposited by computer assisted advanced PLD method in order to obtain transparent, conductive and homogeneous films on a large area. The films were deposited on glass substrates. We studied the influence of the temperature (room temperature (RT)-180 deg. C), pressure (1-6 x 10 -2 Torr), laser fluence (1-4 J/cm 2 ) and wavelength (266-355 nm) on the film properties. The deposition rate, roughness, film structure, optical transmission, electrical conductivity measurements were done. We deposited uniform ITO thin films (thickness 100-600 nm, roughness 5-10 nm) between RT and 180 deg. C on a large area (5 x 5 cm 2 ). The films have electrical resistivity of 8 x 10 -4 Ω cm at RT, 5 x 10 -4 Ω cm at 180 deg. C and an optical transmission in the visible range, around 89%

  11. Atmospheric deposition 2000. NOVA 2003; Atmosfaerisk deposition 2000. NOVA 2003

    Energy Technology Data Exchange (ETDEWEB)

    Ellermann, T.; Hertel, O.; Hovmand, M.F.; Kemp, K.; Skjoeth, C.A.

    2001-11-01

    This report presents measurements and calculations from the atmospheric part of NOVA 2003 and covers results for 2000. It summarises the main results concerning concentrations and depositions of nitrogen, phosphorus and sulphur compounds related to eutrophication and acidification. Depositions of atmospheric compounds to Danish marine waters as well as land surface are presented. Measurements: In 2000 the monitoring program consisted of eight stations where wet deposition of ammonium, nitrate, phosphate (semi quantitatively) and sulphate were measured using bulk precipitation samplers. Six of the stations had in addition measurements of atmospheric content of A, nitrogen, phosphorus, and sulphur compounds in gas and particulate phase carried out by use of filter pack samplers. Filters were analysed at the National Environmental Research Institute. Furthermore nitrogen dioxide were measured using nitrogen dioxide filter samplers and monitors. Model calculations: The measurements in the monitoring program were supplemented with model calculations of concentrations and depositions of nitrogen and sulphur compounds to Danish land surface, marine waters, fjords and bays using the ACDEP model (Atmospheric Chemistry and Deposition). The model is a so-called trajectory model and simulates the physical and chemical processes in the atmosphere using meteorological and emission data as input. The advantage of combining measurements with model calculations is that the strengths of both methods is obtained. Conclusions concerning: 1) actual concentration levels at the monitoring stations, 2) deposition at the monitoring stations, 3) seasonal variations and 4) long term trends in concentrations and depositions are mainly based on the direct measurements. These are furthermore used to validate the results of the model calculations. Calculations and conclusions concerning: 1) depositions to land surface and to the individual marine water, 2) contributions from different emission

  12. Particle deposition in ventilation ducts

    Energy Technology Data Exchange (ETDEWEB)

    Sippola, Mark Raymond [Univ. of California, Berkeley, CA (United States)

    2002-09-01

    Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 μm were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on the

  13. Acid Deposition Maps in Spain

    International Nuclear Information System (INIS)

    Artinano, B.; Cabal, H.; Garcia, C.

    1998-01-01

    Animal and monthly deposition velocity and total sulfur deposition maps have been performed for the peninsular Spain for 1992 by using the inferential method. To do this, updated databases with high space and time resolution, for land uses (CORINE) and meteorological information from analysis modelling for the same year, have been utilized. The final result are deposition maps in a 5x5 Km 2 grid which allow to assess the methodology used in Europe to obtain the maps of excedances over the critical loads of pollutants. (Author) 32 refs

  14. The anthracite of Nazar-Aylok Deposit

    International Nuclear Information System (INIS)

    Pachadzhanov, D.N.; Valiev, Yu.Ya.

    2013-01-01

    Present article is devoted to anthracite of Nazar-Aylok Deposit. The ash content, composition of coals of Nazar-Aylok Deposit and thickness of deposit were considered. The coal samples were studied by means of neutron activation analysis.

  15. Deposition of Boron in Possible Evaporite Deposits in Gale Crate

    Science.gov (United States)

    Gasda, P. J.; Peets, E.; Lamm, S. N.; Rapin, W.; Lanza, N.; Frydenvang, J.; Clark, B. C.; Herkenhoff, K. E.; Bridges, J.; Schwenzer, S. P.; Haldeman, E. B.; Wiens, R. C.; Maurice, S.; Clegg, S. M.; Delapp, D.; Sanford, V.; Bodine, M. R.; McInroy, R.

    2017-12-01

    Boron has been previously detected in Gale crater using the ChemCam instrument on board the NASA Curiosity rover within calcium sulfate fracture fill hosted by lacustrine mudstone and eolian sandstone units. Recent results show that up to 300 ppm B is present in the upper sections of the lacustrine unit. Boron has been detected in both the groundwater-emplaced calcium sulfate fracture fill materials and bedding-parallel calcium sulfate layers. The widespread bedding-parallel calcium sulfate layers within the upper strata of the lacustrine bedrock that Curiosity has encountered recently could be interpreted as primary evaporite deposits. We have two hypotheses for the history of boron in Gale crater. In both hypotheses, borates were first deposited as lake water evaporated, depositing primary evaporates that were later re-dissolved by groundwater, which redistributed the boron into secondary evaporitic calcium sulfate fracture fill deposits. In the first scenario, Gale crater may have undergone a period of perennial lake formation during a drier period of martian history, depositing layers of evaporitic minerals (including borates) among lacustrine mudstone layers. In the second scenario, lake margins could have become periodically exposed during cyclic drops in lake level and subsequently desiccated. Evaporites were deposited and desiccation features were formed in lowstand deposits. Either hypothetical scenario of evaporite deposition would promote prebiotic chemical reactions via wet-dry cycles. Boron may be an important prebiotic element, and as such, its presence in ancient martian surface and groundwater provides evidence that important prebiotic chemical reactions could occur on Mars if organics were present. The presence of boron in ancient Gale crater groundwater also provides additional evidence that a habitable environment existed in the martian subsurface well after the expected disappearance of liquid water on the surface of Mars. We will report on the

  16. Atomic layer deposition for semiconductors

    CERN Document Server

    Hwang, Cheol Seong

    2014-01-01

    This edited volume discusses atomic layer deposition (ALD) for all modern semiconductor devices, moving from the basic chemistry of ALD and modeling of ALD processes to sections on ALD for memories, logic devices, and machines.

  17. Gasoline from Kumkol deposit petroleum

    International Nuclear Information System (INIS)

    Nadirov, A.N.; Zhizhin, N.I.; Musaeva, Z.G.

    1997-01-01

    Samples of gasoline from petroleum of Kumkol deposit are investigated by chromatographic analysis. It is found, that gasoline is characterizing by increased content of iso-paraffin hydrocarbons. (author)

  18. Electrospark deposition for die repair

    Directory of Open Access Journals (Sweden)

    J. Tušek

    2012-01-01

    Full Text Available The electrospark deposition is a process for surfacing of hard metal alloys, e.g. carbides and stellites, on the surfaces of new or old machine elements. In this process, a high current is conducted through an oscillating electrode and a substrate for a very short period of time. In the paper, the process is described and the thickness of deposited layer, chemical composition, dilution rate and the layer roughness are determined.

  19. A radon progeny deposition model

    International Nuclear Information System (INIS)

    Rielage, Keith; Elliott, Steven R.; Hime, Andrew; Guiseppe, Vincent E.; Westerdale, S.

    2010-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222 Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of 210 Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  20. A Radon Progeny Deposition Model

    International Nuclear Information System (INIS)

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222 Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of 210 Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  1. Legal Deposit of Electronic Publications

    Directory of Open Access Journals (Sweden)

    Burcu Umut Zan

    2009-06-01

    Full Text Available The most important and basic role of the deposition studies, which are the greatest contributions to the knowledge sharing, is to gather the artistic and philosophical works of a country and provide them for the use of future researchers. However, since early deposition studies were limited with printed publications, they do not involve the electronic publication types appearing with the development of information technology. This stems from the fact that the electronic publications require procedures different from those of the printed publications in terms of deposition steps because of their structures. Today, in order to guarantee that all registered cultural products, which are mostly produced and used in the electronic environment could be fully collected, electronic publications should also be covered by and regulated under legal deposit. This study analyzes the deposition of electronic publications, within the framework of their storage and protection, being put in the use of the users as well as the common approaches to deposition practices in the world parallel to the developments in the information technology. The related situation in Turkey was also evaluated.

  2. Felsic magmatism and uranium deposits

    International Nuclear Information System (INIS)

    Cuney, Michel

    2014-01-01

    The strongly incompatible behaviour of uranium in silicate magmas results in its concentration in the most felsic melts and a prevalence of granites and rhyolites as primary U sources for the formation of U deposits. Despite its incompatible behavior, U deposits resulting directly from magmatic processes are quite rare. In most deposits, U is mobilized by hydrothermal fluids or ground water well after the emplacement of the igneous rocks. Of the broad range of granite types, only a few have U contents and physico-chemical properties that permit the crystallization of accessory minerals from which uranium can be leached for the formation of U deposits. The first granites on Earth, which crystallized uraninite, dated at 3.1 Ga, are the potassic granites from the Kaapval craton (South Africa) which were also the source of the detrital uraninite for the Dominion Reef and Witwatersrand quartz pebble conglomerate deposits. Four types of granites or rhyolites can be sufficiently enriched in U to represent a significant source for the genesis of U deposits: per-alkaline, high-K met-aluminous calc-alkaline, L-type peraluminous and anatectic pegmatoids. L-type peraluminous plutonic rocks in which U is dominantly hosted in uraninite or in the glass of their volcanic equivalents represent the best U source. Per-alkaline granites or syenites are associated with the only magmatic U-deposits formed by extreme fractional crystallization. The refractory character of the U-bearing minerals does not permit their extraction under the present economic conditions and make them unfavorable U sources for other deposit types. By contrast, felsic per-alkaline volcanic rocks, in which U is dominantly hosted in the glassy matrix, represent an excellent source for many deposit types. High-K calc-alkaline plutonic rocks only represent a significant U source when the U-bearing accessory minerals (U-thorite, allanite, Nb oxides) become metamict. The volcanic rocks of the same geochemistry may be

  3. Felsic magmatism and uranium deposits

    International Nuclear Information System (INIS)

    Cuney, M.

    2014-01-01

    Uranium strongly incompatible behaviour in silicate magmas results in its concentration in the most felsic melts and a prevalence of granites and rhyolites as primary U sources for the formation of U deposits. Despite its incompatible behaviour, U deposits resulting directly from magmatic processes are quite rare. In most deposits, U is mobilized by hydrothermal fluids or ground water well after the emplacement of the igneous rocks. Of the broad range of granite types, only a few have have U contents and physico-chemical properties that permit the crystallization of accessory minerals from which uranium can be leached for the formation of U deposits. The first granites on Earth which crystallized uraninite appeared at 3.1 Ga, are the potassic granites from the Kaapval craton (South Africa) which were also the source of the detrital uraninite for the Dominion Reef and Witwatersrand quartz pebble conglomerate deposits. Four types of granites or rhyolites can be sufficiently enriched in U to represent a significant source for the genesis of U deposits: peralkaline, high-K metaluminous calc-alkaline, L-type peraluminous ones and anatectic pegmatoids. L-type peraluminous plutonic rocks in which U is dominantly hosted in uraninite or in the glass in their volcanic equivalents represent the best U source. Peralkaline granites or syenites represent the only magmatic U-deposits formed by extreme fractional crystallization. The refractory character of the U-bearing minerals does not permit their extraction at the present economic conditions and make them unfavourable U sources for other deposit types. By contrast, felsic peralkaline volcanic rocks, in which U is dominantly hosted in the glassy matrix, represent an excellent source for many deposit types. High-K calc-alkaline plutonic rocks only represent a significant U source when the U-bearing accessory minerals [U-thorite, allanite, Nb oxides] become metamict. The volcanic rocks of the same geochemistry may be also a

  4. Vein-type uranium deposits

    International Nuclear Information System (INIS)

    Rich, R.A.; Holland, H.D.; Petersen, U.

    1975-01-01

    A critical review is presented of published data bearing on the mineralogy, paragenesis, geochemistry, and origin of veiw-type uranium deposits. Its aim is to serve as a starting point for new research and as a basis for the development of new exploration strategies. During the formation of both vein and sandstone types of deposits uranium seems to have been dissolved by and transported in rather oxidized solutions, and deposited where these solutions encountered reducing agents such as carbon, sulfides, ferrous minerals and hydrocarbons. Granitic rocks abnormally enriched in uranium have apparently been the most common source for uranium in vein-type deposits. Oxidizing solutions have been derived either from the surface or from depth. Surface solutions saturated with atmospheric oxygen have frequently passed through red bed or clean sandstone conduits on their way to and from uranium source rocks. Deep solutions of non-surface origin have apparently become sufficiently oxidizing by passage through and equilibration with red beds. The common association of clean sandstones or red beds with uranium-rich granites in the vicinity of vein-type uranium deposits is probably not fortuitous, and areas where these rock types are found together are considered particularly favorable targets for uranium exploration

  5. Restoration of uranium solution mining deposits

    International Nuclear Information System (INIS)

    Devries, F.W.; Lawes, B.C.

    1982-01-01

    A process is provided for restoring an ore deposit after uranium solution mining using ammonium carbonate leaching solutions has ceased. The process involves flushing the deposit with an aqueous solution of a potassium salt during which potassium ions exchange with ammonium ions remaining in the deposit. The ammonium containing flushing solution is withdrawn from the deposit for disposal

  6. Understanding the spectrum of diesel injector deposits

    Energy Technology Data Exchange (ETDEWEB)

    Quigley, Robert; Barbour, Robert [Lubrizol Limited, Derby (United Kingdom); Arters, David; Bush, Jim [Lubrizol Corporation, Wickliffe, OH (United States)

    2013-06-01

    Understanding the origin of diesel fuel injector deposits used to be relatively simple; for the most part they were caused by the decomposition of fuel during the combustion process, were generally organic in nature and typically only affected the nozzle orifices. However, modem fuel injector designs appear to be both more severe in terms of generating conditions conducive to creating new and different types of deposits and more likely to have their operation affected by those deposits. Changes to fuel composition and type have in some cases increased the potential pool of reactive species or provided new potential deposit precursors. As a result, the universe of diesel injector deposits now range from the traditional organic to partially or fully inorganic in nature and from nozzle coking deposits to deposits which can seize the internal components of the injector; so called internal diesel injector deposits. Frequently, combinations of inorganic and organic deposits are found. While power loss is one well known issue associated with nozzle deposits, other field problems resulting from these new deposits include severe issues with drivability, emissions, fuel consumption and even engine failure. Conventional deposit control additive chemistries were developed to be effective against organic nozzle coking deposits. These conventional additives in many cases may prove ineffective against this wide range of deposit types. This paper discusses the range of deposits that have been found to adversely impact modem diesel fuel injectors and compares the performance of conventional and new, advanced deposit control additives against these various challenges to proper fuel injector functioning. (orig.)

  7. Restoration of uranium solution mining deposits

    Energy Technology Data Exchange (ETDEWEB)

    Devries, F.W.; Lawes, B.C.

    1982-01-19

    A process is provided for restoring an ore deposit after uranium solution mining using ammonium carbonate leaching solutions has ceased. The process involves flushing the deposit with an aqueous solution of a potassium salt during which potassium ions exchange with ammonium ions remaining in the deposit. The ammonium containing flushing solution is withdrawn from the deposit for disposal.

  8. Analysing the Cenozoic depositional record

    DEFF Research Database (Denmark)

    Goledowski, Bartosz; Clausen, O.R.; Nielsen, S.B.

    2008-01-01

    It is well known that sediment deposition in the North Sea and on the Norwegian Shelf varied significantly during the Cenozoic as a consequence of varying erosion rate mainly in Western Scandinavia, in Scotland and in the Alps. Recent results have demonstrated that a causal relationship exists...... of variations in erosion rates. Here we present the rationale behind the project, the data available and some preliminary results. The dense seismic and well coverage in the area makes it possible to estimate the rate of deposition of matrix mass. Assuming that sediment storage is not important, this provides...... models. The matrix mass deposition history will be compared with the paleoclimate record (e.g. oxygen isotope curves) to see if the previously observed correlation in the eastern North Sea can be extended to other ages and locations.  ...

  9. Surficial uranium deposits in Algeria

    International Nuclear Information System (INIS)

    Mokaddem, M.; Fuchs, Y.

    1984-01-01

    Along southern border of the Hoggar (Algeria) Precambrian shield, Lower Palaeozoic sediments lie unconformably on weathered metamorphic rocks. Along the eastern border of the Tin Seririne basin some good examples of the weathered rocks underneath the unconformity are exposed. The palaeosurface is a peneplain with only minor topographical reliefs from one to a few metres high. The nature and intensity of the weathering process was controlled by the topography, and the existence of badly drained areas is particularly important. At one such area the Tahaggart uranium ore deposit was discovered. The uranium ore consists mainly of torbernite and autunite. The deposit is present in the weathered gneiss underneath the palaeosurface. Mineralogical and geochemical observations indicated that the ore deposit was formed during the period of weathering which was controlled by climatological and palaeotopographical factors. (author)

  10. Sub-aerial tailings deposition

    International Nuclear Information System (INIS)

    Knight, R.B.; Haile, J.P.

    1984-01-01

    The sub-aerial technique involves the systematic deposition of tailings in thin layers and allowing each layer to settle, drain and partially air dry prior to covering with a further layer. Underdrainage produces densities in excess of those achieved by sub-aqueous deposition and any air-drying serves to preconsolidate each layer with a resulting further increase in density. The low permeability of the tailings surface resulting from this deposition technique results in high runoff coefficients and, by decanting the runoff component of direct precipitation, a net evaporation condition can be achieved even in high rainfall areas. An underdrainage system prevents the build-up of excess pore-pressures within the tailings mass and at decommissioning the tailings are fully consolidated and drained thereby eliminating the possibility of any long term seepage. This paper presents a general description of these design concepts, and details of two projects where the concepts have been applied

  11. TULSA UNIVERSITY PARAFFIN DEPOSITION PROJECTS

    Energy Technology Data Exchange (ETDEWEB)

    Cem Sarica; Michael Volk

    2004-06-01

    As oil and gas production moves to deeper and colder water, subsea multiphase production systems become critical for economic feasibility. It will also become increasingly imperative to adequately identify the conditions for paraffin precipitation and predict paraffin deposition rates to optimize the design and operation of these multi-phase production systems. Although several oil companies have paraffin deposition predictive capabilities for single-phase oil flow, these predictive capabilities are not suitable for the multiphase flow conditions encountered in most flowlines and wellbores. For deepwater applications in the Gulf of Mexico, it is likely that multiphase production streams consisting of crude oil, produced water and gas will be transported in a single multiphase pipeline to minimize capital cost and complexity at the mudline. Existing single-phase (crude oil) paraffin deposition predictive tools are clearly inadequate to accurately design these pipelines, because they do not account for the second and third phases, namely, produced water and gas. The objective of this program is to utilize the current test facilities at The University of Tulsa, as well as member company expertise, to accomplish the following: enhance our understanding of paraffin deposition in single and two-phase (gas-oil) flows; conduct focused experiments to better understand various aspects of deposition physics; and, utilize knowledge gained from experimental modeling studies to enhance the computer programs developed in the previous JIP for predicting paraffin deposition in single and two-phase flow environments. These refined computer models will then be tested against field data from member company pipelines.

  12. Hereditary iron and copper deposition

    DEFF Research Database (Denmark)

    Aaseth, Jan; Flaten, Trond Peder; Andersen, Ole

    2007-01-01

    Hereditary deposition of iron (primary haemochromatosis) or copper (Wilson's disease) are autosomal recessive metabolic disease characterized by progressive liver pathology and subsequent involvement of various other organs. The prevalence of primary haemochromatosis is approximately 0.5%, about......, they may be inadequate in patients diagnosed so late that extensive body deposits of metal have been developed. The main research needs in this field are to further clarify molecular mechanisms of disease progression and to develop new chelators that are more effective and less toxic than those presently...

  13. Investigation on radioactivity of deposition

    International Nuclear Information System (INIS)

    Vaas, L.H.; Smetsers, R.C.G.M.; Mattern, F.C.M.; Drost, R.M.S. van; Ockhuizen, A.; Glastra, P.; Koolwijk, A.C.

    1990-04-01

    This report of the Dutch National Institute of Public Health and Environmental Protection (RIVM) summarizes the results of measurements of radionuclides deposited in the Netherlands in 1988. The samples of deposition were taken at Bilthoven, located near the center of the country. In 1988 measurements were carried out to determine the activities of γ-emitters, where 7 Be, 40 K, 134 Cs and 137 Cs were identified, and those of 3 H, 210 Pb and 210 Po. Also the gross α-, gross β- and gross γ-activities were determined. (author). 10 refs.; 7 figs.; 6 tabs

  14. Mathematical geology studies of deposit prospect types

    International Nuclear Information System (INIS)

    Liu Guangping

    1998-08-01

    Exact certainty prospect type of uranium deposit, not only can assure the quality of deposit prospects, but also increase economic benefits. Based on the standard of geological prospect of uranium deposit, the author introduces a method of Fuzzy Synthetical Comment for dividing prospect type of uranium deposit. The practical applications demonstrate that the regression accuracy, discriminated by Zadeh operator, of 15 known deposits is 100%

  15. Bank deposits, notions and features of accounting

    Directory of Open Access Journals (Sweden)

    Georgeta MELNIC

    2016-06-01

    Full Text Available Bank deposits are the main method of raising capital and short-term available savings. The opening and using of the bank deposits is the main function of banks. In 2004 the Deposit Guarantee Fund was set up in the Republic of Moldova of Deposit Guarantee Fund and for the first time there was established a guaranteed bank minimum in case of bank insolvency which is currently 6,000 lei for the deposit of each natural person.

  16. Advanced deposition model for thermal activated chemical vapor deposition

    Science.gov (United States)

    Cai, Dang

    Thermal Activated Chemical Vapor Deposition (TACVD) is defined as the formation of a stable solid product on a heated substrate surface from chemical reactions and/or dissociation of gaseous reactants in an activated environment. It has become an essential process for producing solid film, bulk material, coating, fibers, powders and monolithic components. Global market of CVD products has reached multi billions dollars for each year. In the recent years CVD process has been extensively used to manufacture semiconductors and other electronic components such as polysilicon, AlN and GaN. Extensive research effort has been directed to improve deposition quality and throughput. To obtain fast and high quality deposition, operational conditions such as temperature, pressure, fluid velocity and species concentration and geometry conditions such as source-substrate distance need to be well controlled in a CVD system. This thesis will focus on design of CVD processes through understanding the transport and reaction phenomena in the growth reactor. Since the in situ monitor is almost impossible for CVD reactor, many industrial resources have been expended to determine the optimum design by semi-empirical methods and trial-and-error procedures. This approach has allowed the achievement of improvements in the deposition sequence, but begins to show its limitations, as this method cannot always fulfill the more and more stringent specifications of the industry. To resolve this problem, numerical simulation is widely used in studying the growth techniques. The difficulty of numerical simulation of TACVD crystal growth process lies in the simulation of gas phase and surface reactions, especially the latter one, due to the fact that very limited kinetic information is available in the open literature. In this thesis, an advanced deposition model was developed to study the multi-component fluid flow, homogeneous gas phase reactions inside the reactor chamber, heterogeneous surface

  17. Deposition and Resuspension of Particles

    DEFF Research Database (Denmark)

    Lengweiler, P.; Nielsen, Peter V.; Moser, A.

    To investigate the physical process of deposition and resuspension of particles in the indoor environment, scale experiments are used and a sampling method is established. The influences of surface orientation and turbulence and velocity of the air on the dust load on a surface are analysed....

  18. Cluster Implantation and Deposition Apparatus

    DEFF Research Database (Denmark)

    Hanif, Muhammad; Popok, Vladimir

    2015-01-01

    In the current report, a design and capabilities of a cluster implantation and deposition apparatus (CIDA) involving two different cluster sources are described. The clusters produced from gas precursors (Ar, N etc.) by PuCluS-2 can be used to study cluster ion implantation in order to develop...

  19. Deposition gradients across mangrove fringes

    NARCIS (Netherlands)

    Horstman, Erik Martijn; Mullarney, Julia C.; Bryan, K.R.; Sandwell, Dean R.; Aagaard, Troels; Deigaard, Rolf; Fuhrman, David

    2017-01-01

    Observations in a mangrove in the Whangapoua Harbour, New Zealand, have shown that deposition rates are greatest in the fringing zone between the tidal flats and the mangrove forest, where the vegetation is dominated by a cover of pneumatophores (i.e. pencil roots). Current speeds and suspended

  20. Uranium extraction from underground deposits

    International Nuclear Information System (INIS)

    Wolfe, C.R.

    1982-01-01

    Uranium is extracted from underground deposits by passing an aqueous oxidizing solution of carbon dioxide over the ore in the presence of calcium ions. Complex uranium carbonate or bicarbonate ions are formed which enter the solution. The solution is forced to the surface and the uranium removed from it

  1. Electrolytic nickel deposits upon uranium

    International Nuclear Information System (INIS)

    Baudin, G.; Chauvin, G.; Coriou, H.; Hure, J.

    1958-01-01

    The authors present a new possibility to protect uranium by very adherent nickel deposits got by aqueous medium electrolysis. Surface treatment of uranium is based upon the chemical etching method from Lietazke. After thermal treatments at 600, 700 and 800 deg. C, under vacuum, a good intermetallic U-Ni diffusion is observed for each case. (author) [fr

  2. IAEA Classification of Uranium Deposits

    International Nuclear Information System (INIS)

    Bruneton, Patrice

    2014-01-01

    Classifications of uranium deposits follow two general approaches, focusing on: • descriptive features such as the geotectonic position, the host rock type, the orebody morphology, …… : « geologic classification »; • or on genetic aspects: « genetic classification »

  3. Advances in energy deposition theory

    International Nuclear Information System (INIS)

    Paretzke, H.G.

    1980-01-01

    In light of the fields of radiation protection and dosimetric problems in medicine, advances in the area of microscopic target related studies are discussed. Energy deposition is discussed with emphasis upon track structures of electrons and heavy charged particles and track computer calculations

  4. Unconformity-related uranium deposits

    International Nuclear Information System (INIS)

    Ewers, G.R.; Ferguson, J.

    1985-01-01

    Documentation of ore deposit characterisation is being undertaken to assess the controls of uranium mineralisation associated with Proterozoic unconformities. The Turee Creek uranium prospect in Western Australia is associated with a faulted contact between the Middle Proterozoic Kunderong Sandstone and the Lower Proterozoic Wyloo Group

  5. Nitrogen deposition and terrestrial biodiversity

    Science.gov (United States)

    Christopher M. Clark; Yongfei Bai; William D. Bowman; Jane M. Cowles; Mark E. Fenn; Frank S. Gilliam; Gareth K. Phoenix; Ilyas Siddique; Carly J. Stevens; Harald U. Sverdrup; Heather L. Throop

    2013-01-01

    Nitrogen deposition, along with habitat losses and climate change, has been identified as a primary threat to biodiversity worldwide (Butchart et al., 2010; MEA, 2005; Sala et al., 2000). The source of this stressor to natural systems is generally twofold: burning of fossil fuels and the use of fertilizers in modern intensive agriculture. Each of these human...

  6. Electro-spark deposition technology

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.N. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-12-01

    Electro-Spark Deposition (ESD) is a micro-welding process that uses short duration, high-current electrical pulses to deposit or alloy a consumable electrode material onto a metallic substrate. The ESD process was developed to produce coatings for use in severe environments where most other coatings fail. Because of the exceptional damage resistance of these coatings, and the versatility of the process to apply a wide variety of alloys, intermetallics, and cermets to metal surfaces, the ESD process has been designated critical to the life and economy of the advanced fossil energy systems as the higher temperatures and corrosive environments exceed the limits of known structural materials to accommodate the service conditions. Developments include producing iron aluminide-based coatings with triple the corrosion resistance of the best previous Fe{sub 3}Al coatings, coatings with refractory metal diffusion barriers and multi layer coatings for achieving functionally gradient properties between the substrate and the surface. A new development is the demonstration of advanced aluminide-based ESD coatings for erosion and wear applications. One of the most significant breakthroughs to occur in the last dozen years is the discovery of a process regime that yields an order of magnitude increase in deposition rates and achievable coating thicknesses. Achieving this regime has required the development of advanced ESD electronic capabilities. Development is now focused on further improvements in deposition rates, system reliability when operating at process extremes, and economic competitiveness.

  7. World distribution of uranium deposits

    Science.gov (United States)

    Fairclough, M. C.; Irvine, J. A.; Katona, L. F.; Simmon, W. L.; Bruneton, P.; Mihalasky, Mark J.; Cuney, M.; Aranha, M.; Pylypenko, O.; Poliakovska, K.

    2018-01-01

    Deposit data derived from IAEA UDEPO (http://infcis.iaea.org/UDEPO/About.cshtml) database with assistance from P. Bruneton (France) and M. Mihalasky (U.S.A.). The map is an updated companion to "World Distribution of Uranium Deposits (UDEPO) with Uranium Deposit Classification, IAEA Tech-Doc-1629". Geology was derived from L.B. Chorlton, Generalized Geology of the World, Geological Survey of Canada, Open File 5529 , 2007. Map production by M.C. Fairclough (IAEA), J.A. Irvine (Austrailia), L.F. Katona (Australia) and W.L. Slimmon (Canada). World Distribution of Uranium Deposits, International Atomic Energy Agency, Vienna, Austria. Cartographic Assistance was supplied by the Geological Survey of South Australia, the Saskatchewan Geological Survey and United States Geological Survey to the IAEA. Coastlines, drainage, and country boundaries were obtained from ArcMap, 1:25 000 000 scale, and are copyrighted data containing the intellectual property of Environmental Systems Research Institute (ESRI). The use of particular designations of countries or territories does not imply any judgment by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. Any revisions or additional geological information known to the user would be welcomed by the International Atomic Energy Agency and the Geological Survey of Canada.

  8. Deposit competition and loan markets

    NARCIS (Netherlands)

    Arping, S.

    Less-intense competition for deposits, by mitigating banks’ incentive to take excessive risks, is traditionally believed to lead to lower non-performing loan (NPL) ratios and more-stable banks. This paper revisits this proposition in a model with borrower moral hazard in which banks’ NPL ratios

  9. The uranium deposits of Ontario

    International Nuclear Information System (INIS)

    Robertson, J.A.

    1981-01-01

    The principal types of uranium deposits in Ontario are carbonatites and fenites, alkalic volcanic rocks, pegiatites, calc-silicate rocks, pyritic quartz-pebble conglomerates, polymictic conglomerates and some pelitic rocks, and various 'pitchblende' deposits including late Precambrian unconformities, possibly late Precambrian diabase dikes, and other unconformities: carbonates, sandstones, lignites, and semi-pelitic rocks of middle and upper Precambrian age. Only red unzoned pegmatite and the pyritic quartz-pebble conglomerate have supported production. Ontario reasonably assured and estimated resources in the economic and subeconomic categories in 1977 amounted to 553 000 tonnes U, and 1977 production was 4000 tonnes U. Measured, indicated, and inferred resources in the Elliot Lake - Agnew Lake area are at least 400 000 tonnes U. The latter deposits are also a significant thorium resource. Geological features reflecting major changes in physics and chemistry are prime controls on distribution of uranium deposits. Geological province and subprovince boundaries, major faults, higher metamorphic grades, domain boundaries related to quartz monzonite batholiths, alkalic complexes, and the distribution of carbonate rocks are examples of such geological features

  10. Persisting roughness when deposition stops.

    Science.gov (United States)

    Schwartz, Moshe; Edwards, S F

    2004-12-01

    Useful theories for growth of surfaces under random deposition of material have been developed by several authors. The simplest theory is that introduced by Edwards and Wilkinson (EW), which is linear and soluble. Its nonlinear generalization by Kardar, Parisi, and Zhang (KPZ) resulted in many subsequent studies. Yet both EW and KPZ theories contain an unphysical feature. When deposition of material is stopped, both theories predict that as time tends to infinity, the surface becomes flat. In fact, of course, the final surface is not flat, but simply has no gradients larger than the gradient related to the angle of repose. We modify the EW and KPZ theories to accommodate this feature and study the consequences for the simpler system which is a modification of the EW equation. In spite of the fact that the equation describing the evolution of the surface is not linear, we find that the steady state in the presence of noise is not very different in the long-wavelength limit from that of the linear EW equation. The situation is quite different from that of EW when deposition stops. Initially there is still some rearrangement of the surface, but that stops as everywhere on the surface the gradient is less than that related to the angle of repose. The most interesting feature observed after deposition stops is the emergence of history-dependent steady-state distributions.

  11. Discharge cleaning of carbon deposits

    International Nuclear Information System (INIS)

    Mozetic, M.; Vesel, A.; Drenik, A.

    2006-01-01

    Experimental results of discharge cleaning of carbon deposits are presented. Deposits were prepared by creating plasma in pure methane. The methane was cracked in RF discharge at the output power of 250 W. The resultant radicals were bonded to the wall of discharge vessel forming a thin film of hydrogenated black carbon with the thickness of about 200nm. The film was then cleaned in situ by oxygen plasma with the density of about 1x10 16 m -3 , electron temperature of 5 eV, neutral gas kinetic temperature of about 100 0 C and neutral atom density of 6x10 21 m -3 . The treatment time was 30 minutes. The efficiency of plasma cleaning was monitored by optical emission spectroscopy. As long as the wall was contaminated with carbon deposit, substantial emission of the CO molecules was detected. As the cleaning was in progress, the CO emission was decreasing and vanished after 30 minutes when the discharge vessel became free of any carbon. The results are explained by interaction of plasma radicals with carbon deposits. (author)

  12. Improving deposition tester to study adherent deposits in papermaking

    OpenAIRE

    Monte Lara, Concepción; Sánchez, Mónica; Blanco Suárez, Ángeles; Negro Álvarez, Carlos; Tijero Miquel, Julio

    2012-01-01

    Conventional methods used for the quantification of adherent material contained in a pulp suspension propose either filtration of the sample, which may lead to loss of sticky material in the filtrate, or dilution of the pulp, which may cause destabilization of the dissolved and colloidal material; thus, leading to unreliable results. In 1998, the Cellulose and Paper Group of University Complutense of Madrid developed a deposition tester which aimed to quantify the adherence of material (micro...

  13. Constructing deposition chronologies for peat deposits using radiocarbon dating

    Directory of Open Access Journals (Sweden)

    N. Piotrowska

    2011-06-01

    Full Text Available Radiocarbon dating is one of the main methods used to establish peat chronologies. This article reviews the basis of the method and its application to dating of peat deposits. Important steps in the radiocarbon dating procedure are described, including selection and extraction of material (and fractions for dating, chemical and physical preparation of media suitable for measurements, measurements of 14C activity or concentration, calculations, calibration of results and age-depth modelling.

  14. Vapor deposition of tantalum and tantalum compounds

    International Nuclear Information System (INIS)

    Trkula, M.

    1996-01-01

    Tantalum, and many of its compounds, can be deposited as coatings with techniques ranging from pure, thermal chemical vapor deposition to pure physical vapor deposition. This review concentrates on chemical vapor deposition techniques. The paper takes a historical approach. The authors review classical, metal halide-based techniques and current techniques for tantalum chemical vapor deposition. The advantages and limitations of the techniques will be compared. The need for new lower temperature processes and hence new precursor chemicals will be examined and explained. In the last section, they add some speculation as to possible new, low-temperature precursors for tantalum chemical vapor deposition

  15. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Jensen, Peter Arendt; Wu, Hao

    2016-01-01

    . Therefore, timely removal of ash deposits is essential for optimal boiler operation. In order to improve the qualitative and quantitative understanding of deposit shedding in boilers, this study investigates the shear adhesion strength of biomass ash deposits on superheater tubes. Artificial biomass ash...... deposits were prepared on superheater tubes and sintered in an oven at temperatures up to 1000 °C. Subsequently, the deposits were sheared off by an electrically controlled arm, and the corresponding adhesion strength was measured. The results reveal the effect of temperature, ash/deposit composition......, sintering duration, and steel type on the adhesion strength....

  16. Dust deposit in recirculation regions

    International Nuclear Information System (INIS)

    Griemert, R.

    1985-03-01

    The present report shows investigations, which have been carried out in a closed duct at forward and backward facing steps. Distribution of fluid velocity and fluid fluctuations in and normal to main flow direction as well as the distribution of Reynolds shear stress have been measured. The mass transfer downstream of a backward facing step has been investigated as well. By using graphite-, copper-, tin- and rubber dust, conditions of deposition have been defined experimentally. A serie of photos shows the filling of a recirculation region downstream of a backward facing step with graphite dust. The present investigations allow to avoid deposition of dust in recirculation regions by selecting the fluid numbers in an appropriate way. (orig.) [de

  17. High throughput semiconductor deposition system

    Science.gov (United States)

    Young, David L.; Ptak, Aaron Joseph; Kuech, Thomas F.; Schulte, Kevin; Simon, John D.

    2017-11-21

    A reactor for growing or depositing semiconductor films or devices. The reactor may be designed for inline production of III-V materials grown by hydride vapor phase epitaxy (HVPE). The operating principles of the HVPE reactor can be used to provide a completely or partially inline reactor for many different materials. An exemplary design of the reactor is shown in the attached drawings. In some instances, all or many of the pieces of the reactor formed of quartz, such as welded quartz tubing, while other reactors are made from metal with appropriate corrosion resistant coatings such as quartz or other materials, e.g., corrosion resistant material, or stainless steel tubing or pipes may be used with a corrosion resistant material useful with HVPE-type reactants and gases. Using HVPE in the reactor allows use of lower-cost precursors at higher deposition rates such as in the range of 1 to 5 .mu.m/minute.

  18. The unending deposit insurance mess.

    Science.gov (United States)

    Kane, E J

    1989-10-27

    The thrift institution deposit insurance mess is rooted in defects in political and bureaucratic accountability. Under existing incentives, covering up evidence of poor regulatory performance and relaxing binding capital requirements are rational governmental responses to widespread industry insolvency. Similarly, aggressive industry risk taking is a rational response by thrift managers to regulatory forbearances. Far from acknowledging these incentive defects, the Bush plan for cleaning up the mess adopts theories that spotlight other causes: specifically, poor thrift management and the deregulation of thrift institution activities and of deposit interest rates. To end the mess, politicians and regulators must jettison these comfortable theories and surrender discretion that permits them to finesse the need to budget for governmental financial commitments.

  19. Geological aspects of acid deposition

    International Nuclear Information System (INIS)

    Bricker, O.P.

    1984-01-01

    The general pattern of rain falling on the earth and reacting with the materials of the lithosphere (the weathering reactions so familiar to every beginning geology student) began soon after the earth was formed and has continued to the present. Anthropogenic additions to the natural acidic components of the atmosphere have increased since the time of the industrial revolution until they now rival or exceed those of the natural system. The severity of the environmental perturbations caused by these anthropogenic additions to the atmosphere has become a hotly debated topic in scientific forums and in the political arena. The six chapters in this book address various aspects of the acid deposition phenomenon from a geological perspective. It is hoped that the geological approach will be useful in bringing the problem more clearly into focus and may shed light on the geochemical processes that modify the chemical composition of acid deposition after it encounters and reacts with the materials of the lithosphere

  20. Broadband electromagnetic analysis of compacted kaolin

    International Nuclear Information System (INIS)

    Bore, Thierry; Scheuermann, Alexander; Wagner, Norman; Cai, Caifang

    2017-01-01

    The mechanical compaction of soil influences not only the mechanical strength and compressibility but also the hydraulic behavior in terms of hydraulic conductivity and soil suction. At the same time, electric and dielectric parameters are increasingly used to characterize soil and to relate them with mechanic and hydraulic parameters. In the presented study electromagnetic soil properties and suction were measured under defined conditions of standardized compaction tests. The impact of external mechanical stress conditions of nearly pure kaolinite was analyzed on soil suction and broadband electromagnetic soil properties. An experimental procedure was developed and validated to simultaneously determine mechanical, hydraulic and broadband (1 MHz–3 GHz) electromagnetic properties of the porous material. The frequency dependent electromagnetic properties were modeled with a classical mixture equation (advanced Lichtenecker and Rother model, ALRM) and a hydraulic-mechanical-electromagnetic coupling approach was introduced considering water saturation, soil structure (bulk density, porosity), soil suction (pore size distribution, water sorption) as well as electrical conductivity of the aqueous pore solution. Moreover, the relaxation behavior was analyzed with a generalized fractional relaxation model concerning a high-frequency water process and two interface processes extended with an apparent direct current conductivity contribution. The different modeling approaches provide a satisfactory agreement with experimental data for the real part. These results show the potential of broadband electromagnetic approaches for quantitative estimation of the hydraulic state of the soil during densification. (paper)

  1. Kaolins in Uruguay; Caolines en el Uruguay

    Energy Technology Data Exchange (ETDEWEB)

    Spoturno, J; Coronel, N

    1980-07-01

    This work belongs to the Syllabus or Mundial monograph about caolines. Its was organized by the number 23 working group caolines genesis of the International geological correlation Unesco programme. History, geology, tectonic development, sedimentation, dating and geochemistry aspects were given in this report.

  2. Local deposition of high-purity Pt nanostructures by combining electron beam induced deposition and atomic layer deposition

    NARCIS (Netherlands)

    Mackus, A.J.M.; Mulders, J.J.L.; Sanden, van de M.C.M.; Kessels, W.M.M.

    2010-01-01

    An approach for direct-write fabrication of high-purity platinum nanostructures has been developed by combining nanoscale lateral patterning by electron beam induced deposition (EBID) with area-selective deposition of high quality material by atomic layer deposition (ALD). Because virtually pure,

  3. Pele Plume Deposit on Io

    Science.gov (United States)

    1997-01-01

    The varied effects of Ionian volcanism can be seen in this false color infrared composite image of Io's trailing hemisphere. Low resolution color data from Galileo's first orbit (June, 1996) have been combined with a higher resolution clear filter picture taken on the third orbit (November, 1996) of the spacecraft around Jupiter.A diffuse ring of bright red material encircles Pele, the site of an ongoing, high velocity volcanic eruption. Pele's plume is nearly invisible, except in back-lit photographs, but its deposits indicate energetic ejection of sulfurous materials out to distances more than 600 kilometers from the central vent. Another bright red deposit lies adjacent to Marduk, also a currently active ediface. High temperature hot spots have been detected at both these locations, due to the eruption of molten material in lava flows or lava lakes. Bright red deposits on Io darken and disappear within years or decades of deposition, so the presence of bright red materials marks the sites of recent volcanism.This composite was created from data obtained by the Solid State Imaging (CCD) system aboard NASA's Galileo spacecraft. The region imaged is centered on 15 degrees South, 224 degrees West, and is almost 2400 kilometers across. The finest details that can be discerned in this picture are about 3 kilometers across. North is towards the top of the picture and the sun illuminates the surface from the west.The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  4. Complexing and hydrothermal ore deposition

    CERN Document Server

    Helgeson, Harold C

    1964-01-01

    Complexing and Hydrothermal Ore Deposition provides a synthesis of fact, theory, and interpretative speculation on hydrothermal ore-forming solutions. This book summarizes information and theory of the internal chemistry of aqueous electrolyte solutions accumulated in previous years. The scope of the discussion is limited to those aspects of particular interest to the geologist working on the problem of hydrothermal ore genesis. Wherever feasible, fundamental principles are reviewed. Portions of this text are devoted to calculations of specific hydrothermal equilibriums in multicompone

  5. Modular plants for small deposits

    International Nuclear Information System (INIS)

    Josa, J.M.; Moral, A.; Otero, J.L.; Suarez, E.

    1985-01-01

    The large investment required to recover uranium from small deposits is the greatest obstacle to their economic development. Various concepts (caravan mill, pure mill or semimobile mill) have been elaborated in different countries. Studies have also been made in Spain to develop a simple and economic flowsheet suitable for the beneficiation of small uranium deposits. An acid heap-leaching and solvent extraction process was chosen because there is already a great deal of experience of it in Spain. Modifications were necessary to make the equipment easy to transport and also to have a low and reusable investment when this flowsheet is used for small deposits. The aim was to develop a modular plant with all the elements fitted in compact units that needs little site preparation and little time and effort to connect the units. A standard small portable crushing plant can be borrowed and the mining operation and heap construction can be put to contract. There is a solvent extraction unit (150 m 3 /d) in continuous operation (24 h/d) and concentrate precipitation and handling facilities. The whole of the equipment is standard and as light as possible. Little civil engineering is required and the erection of the plant only needs a few months. The uranium capacity of these modular plants is between 35 and 50 t U 3 O 8 /a. Special consideration has been paid to regulations and the environmental aspects. (author)

  6. Potential use of a chemical leaching reject from a kaolin industry as agricultural fertilizer Uso potencial do resíduo químico lixiviado duma indústria de caulim como adubo de terras agrícolas

    Directory of Open Access Journals (Sweden)

    Fabiana Rodrigues Ribeiro

    2007-10-01

    Full Text Available The industrial refining of kaolin involves the removal of iron oxides and hydroxides along with other impurities that cause discoloration of the final product and depreciate its commercial value, particularly undesirable if destined to the paper industry. The chemical leaching in the industrial processing requires treatments with sodium hyposulfite, metallic zinc, or sulfuric and phosphoric acids, in order to reduce, dissolve and remove ferruginous compounds. To mitigate the environmental impact, the acidic effluent from the leaching process must be neutralized, usually with calcium oxide. The resulting solid residue contains phosphorous, zinc, and calcium, among other essential nutrients for plant growth, suggesting its use as a macro and micronutrient source. Samples of such a solid industrial residue were used here to evaluate their potential as soil fertilizer in an incubation greenhouse experiment with two soil samples (clayey and medium-textured. The small pH shift generated by applying the residue to the soil was not a limiting factor for its use in agriculture. The evolution of the concentrations of exchangeable calcium, and phosphorous and zinc extractability by Mehlich-1 extractant during the incubation period confirms the potential use of this industrial residue as agricultural fertilizer.O beneficiamento industrial do caulim envolve a remoção de óxidos e hidróxidos de ferro e outras impurezas, que conferem coloração indesejável ao produto final e depreciam seu valor comercial, particularmente se destinado à indústria de papel. A lixiviação química, na linha de processamento industrial, pode ser feita com tratamentos com hipossulfito de sódio, zinco metálico e ácidos sulfúrico e fosfórico, para redução, solubilização e remoção de compostos ferruginosos. A fim de minimizar o impacto ambiental, o efluente ácido, procedente da etapa de lixiviação, deve ser inicialmente neutralizado, usualmente por óxido de c

  7. Uranium deposits obtention for fission chambers

    International Nuclear Information System (INIS)

    Artacho Saviron, E.

    1972-01-01

    The obtention of uranium deposits of the required quality for small cylindrical fission chambers presents some difficulties. With the method of electroplating here described the uniformity, reproducibility and adherence of the obtained deposits were satisfactory. (Author) 6 refs

  8. Federal Deposit Insurance Corporation (FDIC) Insured Banks

    Data.gov (United States)

    Department of Homeland Security — The Summary of Deposits (SOD) is the annual survey of branch office deposits for all FDIC-insured institutions including insured U.S. branches of foreign banks. Data...

  9. Influência da adição de resíduo de caulim nas propriedades tecnológicas de uma massa padrão de porcelanato produzido em escala industrial Influence of kaolin waste addition on technological properties of a standard stoneware formulation produced in industrial scale

    Directory of Open Access Journals (Sweden)

    M. L. Varela

    2009-06-01

    Full Text Available Atualmente existe uma grande preocupação por parte das indústrias com a disposição dos resíduos gerados ao longo do processo produtivo. No setor mineral não é diferente, pois este gera grande volume de resíduos. Verificou-se que a indústria de beneficiamento do caulim descarta grandes volumes de resíduo constituído basicamente de caulinita, mica muscovita e quartzo, ocasionando um impacto ambiental, o que tem justificado os esforços de pesquisas para sua solução. Deste modo, foi estudado o efeito da incorporação de um resíduo proveniente do beneficiamento de caulim sobre as propriedades físicas e tecnológicas de revestimentos cerâmicos de alta qualidade. O objetivo é caracterizar e estudar o processamento do resíduo proveniente da indústria de beneficiamento do caulim com adição de uma "massa padrão", fornecida por uma indústria de revestimento cerâmico. O resíduo foi caracterizado por meio de análises de difração de raios X, fluorescência de raios X e determinação do tamanho de partículas. Foram realizados ensaios de absorção de água, porosidade aparente, retração linear após queima, massa específica aparente e tensão de ruptura à flexão, para determinação das propriedades tecnológicas destes materiais. Os resultados mostram que o resíduo estudado pode ser considerado como matéria-prima de grande potencial para a indústria de pisos e revestimentos cerâmicos.There is a great concern by the industrial area on the disposal of waste generated during the production process. In the mineral sector the situation is the same, because large volumes of waste are disposed. The kaolin processing industry generates waste consisting mainly of kaolinite, mica and quartz muscovite, causing an environmental impact, justifying the research efforts to find a solution for this problem. The effect of the waste from the kaolin processing incorporation on the technological and physical properties of high quality

  10. Acidic deposition and global climate change

    International Nuclear Information System (INIS)

    Nikolaidis, N.P.; Ecsedy, C.; Olem, H.; Nikolaidis, V.S.

    1990-01-01

    A literature is presented which examines the research published on understanding ecosystem acidification and the effects of acidic deposition on freshwaters. Topics of discussion include the following: acidic deposition; regional assessments; atmospheric deposition and transport; aquatic effects; mathematical modeling; liming acidic waters; global climate change; atmospheric changes; climate feedbacks; and aquatic effects

  11. 42 CFR 422.388 - Deposits.

    Science.gov (United States)

    2010-10-01

    ... to CMS. (2) The deposit must at all times have a fair market value of an amount that is 120 percent... is made; (2) The fair market value exceeds the amount of the required deposit; or (3) The required... PROGRAM MEDICARE ADVANTAGE PROGRAM Provider-Sponsored Organizations § 422.388 Deposits. (a) Insolvency...

  12. 19 CFR 210.28 - Depositions.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Depositions. 210.28 Section 210.28 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Discovery and Compulsory Process § 210.28 Depositions. (a) When depositions may be...

  13. 47 CFR 32.4040 - Customers' deposits.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Customers' deposits. 32.4040 Section 32.4040... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.4040 Customers' deposits. (a) This account shall include the amount of cash deposited with the company by customers as security...

  14. Dry deposition of particles to ocean surfaces

    NARCIS (Netherlands)

    Larsen, S.E.; Edson, J.B.; Hummelshoj, P.; Jensen, N.O.; Leeuw, G. de; Mestayer, P.G.

    1995-01-01

    Dry deposition of atmospheric particles mainly depends on wind speed and particle diameter. The dry deposition velocity, Vd, is found to vary by a factor of 100-1,000 with diameter in a likely diameter range, adding uncertainty to deposition estimates, because the diameter distribution for many

  15. European wet deposition maps based on measurements

    NARCIS (Netherlands)

    Leeuwen EP van; Erisman JW; Draaijers GPJ; Potma CJM; Pul WAJ van; LLO

    1995-01-01

    To date, wet deposition maps on a European scale have been based on long-range transport model results. For most components wet deposition maps based on measurements are only available on national scales. Wet deposition maps of acidifying components and base cations based on measurements are needed

  16. Low-pressure chemical vapor deposition as a tool for deposition of thin film battery materials

    NARCIS (Netherlands)

    Oudenhoven, J.F.M.; Dongen, van T.; Niessen, R.A.H.; Croon, de M.H.J.M.; Notten, P.H.L.

    2009-01-01

    Low Pressure Chemical Vapor Deposition was utilized for the deposition of LiCoO2 cathode materials for all-solid-state thin-film micro-batteries. To obtain insight in the deposition process, the most important process parameters were optimized for the deposition of crystalline electrode films on

  17. Dual Nitrate Isotopes in Dry Deposition: Utility for Partitioning Nox Source Contributions to Landscape Nitrogen Deposition

    Science.gov (United States)

    Dry deposition is a major component of total nitrogen deposition and thus an important source of bioavailable nitrogen to ecosystems. However, relative to wet deposition, less is known regarding the sources and spatial variability of dry deposition. This is in part due to diffi...

  18. Towards a genetic classification of uranium deposits

    International Nuclear Information System (INIS)

    Cuney, M.

    2009-01-01

    As the IAEA's uranium deposit classification is based on the deposit nature and morphology, some deposits which have been formed by very different genetic processes and located in very different geological environments, are grouped according to this classification. In order to build up a reliable genetic classification based on the mechanism at the origin of the formation of the deposit, the author presents the five main categories according to which uranium deposits can be classified: magmatic, hydrothermal, evapotranspiration, syn-sedimentary, and infiltration of meteoric water

  19. Minerals deposited as thin films

    International Nuclear Information System (INIS)

    Vazquez, Cristina; Leyt, D.V. de; Custo, Graciela

    1987-01-01

    Free matrix effects are due to thin film deposits. Thus, it was decided to investigate this technique as a possibility to use pure oxide of the desired element, extrapolating its concentration from analytical curves made with avoiding, at the same time, mathematical corrections. The proposed method was employed to determine iron and titanium concentrations in geological samples. The range studied was 0.1-5%m/m for titanium and 5-20%m/m for iron. For both elements the reproducibility was about 7% and differences between this method and other chemical determinations were 15% for titanium and 7% for iron. (Author) [es

  20. Hinkler Well - Centipede uranium deposits

    International Nuclear Information System (INIS)

    Crabb, D.; Dudley, R.; Mann, A.W.

    1984-01-01

    The Hinkler Well - Centipede deposits are near the northeastern margin of the Archean Yilgarn Block on a drainage system entering Lake Way. Basement rocks are granitoids and greenstones. The rocks are deeply weathered and overlain by alluvism. Granitoids, the probable uranium source, currently contain up to 25 ppm uranium, in spite of the weathering. The host calcrete body is 33 km long and 2 km wide. Uranium up to 1000 ppm occurs in carnotite over a 15 km by 2.5 km area. (author)

  1. Surficial uranium deposits: summary and conclusions

    International Nuclear Information System (INIS)

    Otton, J.K.

    1984-01-01

    Uranium occurs in a variety of surficial environments in calcretes, gypcretes, silcretes, dolocretes and in organic sediments. Groundwater moving on low gradients generates these formations and, under favourable circumstances, uranium deposits. A variety of geomorphic settings can be involved. Most surficial deposits are formed in desert, temperate wetland, tropical, or transitional environments. The largest deposits known are in sedimentary environments in arid lands. The deposits form largely by the interaction of ground or surface waters on the geomorphic surface in favourable geologic terrains and climates. The deposits are commonly in the condition of being formed or reconstituted, or being destroyed. Carnotite is common in desert deposits while in wetland deposits no uranium minerals may be seen. Radioactive disequilibrium is common, particularly in wetland deposits. Granites and related rocks are major source rocks and most large deposits are in regions with enriched uranium contents, i.e. significantly greater than 5 ppm uranium. Uranium dissolution and transport is usually under oxidizing conditions. Transport in desert conditions is usually as a bicarbonate. A variety of fixation mechanisms operate to extract the uranium and form the deposits. Physical barriers to groundwater flow may initiate ore deposition. Mining costs are likely to be low because of the near surface occurrence, but there may be processing difficulties as clay may be present and the saline or carbonate content may be high. (author)

  2. Carbon deposition and hydrogen retention in tokamak

    International Nuclear Information System (INIS)

    Tanabe, Tetsuo

    2006-01-01

    The results of measurements on co-deposition of hydrogen isotopes and wall materials, hydrogen retention, redeposition of carbon and deposition of hydrogen on PMI of JT-60U are described. From above results, selection of plasma facing material and ability of carbon wall is discussed. Selection of plasma facing materials in fusion reactor, characteristics of carbon materials as the plasma facing materials, erosion, transport and deposition of carbon impurity, deposition of tritium in JET, results of PMI in JT-60, application of carbon materials to PFM of ITER, and future problems are stated. Tritium co-deposition in ITER, erosion and transport of carbon in tokamak, distribution of tritium deposition on graphite tile used as bumper limiter of TFTR, and measurement results of deposition of tritium on the Mark-IIA divertor tile and comparison between them are described. (S.Y.)

  3. Electrostatic Deposition of Large-Surface Graphene

    Directory of Open Access Journals (Sweden)

    Charles Trudeau

    2018-01-01

    Full Text Available This work describes a method for electrostatic deposition of graphene over a large area using controlled electrostatic exfoliation from a Highly Ordered Pyrolytic Graphite (HOPG block. Deposition over 130 × 130 µm2 with 96% coverage is achieved, which contrasts with sporadic micro-scale depositions of graphene with little control from previous works on electrostatic deposition. The deposition results are studied by Raman micro-spectroscopy and hyperspectral analysis using large fields of view to allow for the characterization of the whole deposition area. Results confirm that laser pre-patterning of the HOPG block prior to cleaving generates anchor points favoring a more homogeneous and defect-free HOPG surface, yielding larger and more uniform graphene depositions. We also demonstrate that a second patterning of the HOPG block just before exfoliation can yield features with precisely controlled geometries.

  4. Remediation of spent block in Uvanas deposit

    International Nuclear Information System (INIS)

    Nurgaziev, M.A.; Iskakov, M.M.

    2012-01-01

    In 2007 by 'Kazatomprom' and 'Mining company' board decision, the branch of 'Mining company', 'Steppe ore management body' is reorganized in structure subdivision, the basic activity of which is organization and carrying out remediation works on spent blocks of PSV uranium deposit. In 2002 works are completed on OVOS for operating deposits Uvanas, Kanjugan, Northern Karamurun and Eastern Minkuduk. The results of present work were reported in IAEA conference. The working project 'Remediation of spent blocks of PSV uranium deposit PV-17 polygon of Steppe ore management body' approved in 2005 was developed for carrying out the remediation works. Works funding were carried out from liquidation fund of the current deposit established in accordance with the Republic of Kazakhstan law 'About interior and interior use'. Deposits remediation is the part of deposit operation life cycle which obliges to operate deposits with minimum expenditures for remediation.

  5. Arc-related porphyry molybdenum deposit model: Chapter D in Mineral deposit models for resource assessment

    Science.gov (United States)

    Taylor, Ryan D.; Hammarstrom, Jane M.; Piatak, Nadine M.; Seal, Robert R.

    2012-01-01

    This report provides a descriptive model for arc-related porphyry molybdenum deposits. Presented within are geological, geochemical, and mineralogical characteristics that differentiate this deposit type from porphyry copper and alkali-feldspar rhyolite-granite porphyry molybdenum deposits. The U.S. Geological Survey's effort to update existing mineral deposit models spurred this research, which is intended to supplement previously published models for this deposit type that help guide mineral-resource and mineral-environmental assessments.

  6. Atmosfærisk deposition

    DEFF Research Database (Denmark)

    Ellermann, T.; Hertel, O.; Kemp, K.

    Kvælstofdepositionen til danske havområder, fjorde, vige og bugte er for 2001 blevet beregnet til 118 ktons N, hvilket er ca. 20 % lavere end i 2000. Tilsvarende er depositionen til landområderne beregnet til 87 ktons N, hvilket svarer til deposition i 2000. Den primære årsag til den højere...... deposition for 1999-2001, i forhold til tidligere år, er ændringer i beregningsmetoden. Den samlede kvælstofdeposition til farvandene er faldet svagt i perioden 1989-2001. Depositionen til landoverflader skønnes ikke ændret betydeligt. Depositionen af svovlforbindelser til danske landområder er for 2001...... estimeret til ca. 20 ktons S. Baseret på store og signifikante fald i koncentrationer og våddeposition af svovl vurderes, at den samlede svovldeposition er faldet med ca. 50% siden 1989. For fosfor vurderes, at der ikke er sket betydelige ændringer i koncentrationer og depositioner. Depositioner og...

  7. Legal Deposit of Digital Materials

    Directory of Open Access Journals (Sweden)

    Erik Oltmans

    2003-09-01

    Full Text Available Digital publishing is causing a real paradigm shift for research institutions and publishers, as well as for libraries. As a consequence these institutions have to develop new policies, new business models and new infrastructures and techniques. A major problem is that, at the same rate at which our world is becoming digital, the digital information is threatened. New types of hardware, computer applications and file formats supersede each other, making our recorded digital information inaccessible in the long-term. In the past years libraries and archives have undertaken several actions and studies on digital preservation issues. For instance the Koninklijke Bibliotheek (KB has jointly with IBM developed a standard-based deposit system: Digital Information Archiving System ( DIAS. Using DIAS the KB realised in 2002 an electronic deposit (the e-Depot and signed archiving agreements with major science publishers for permanent keeping of their digital materials. In this paper I will discuss the fully operational e-Depot at the KB. I will focus on the data flow of processing the digital publications, and I will address the issue of digital preservation in detail.

  8. Aerosol Deposition in Health and Disease

    Science.gov (United States)

    2012-01-01

    Abstract The success of inhalation therapy is not only dependent upon the pharmacology of the drugs being inhaled but also upon the site and extent of deposition in the respiratory tract. This article reviews the main mechanisms affecting the transport and deposition of inhaled aerosol in the human lung. Aerosol deposition in both the healthy and diseased lung is described mainly based on the results of human studies using nonimaging techniques. This is followed by a discussion of the effect of flow regime on aerosol deposition. Finally, the link between therapeutic effects of inhaled drugs and their deposition pattern is briefly addressed. Data show that total lung deposition is a poor predictor of clinical outcome, and that regional deposition needs to be assessed to predict therapeutic effectiveness. Indeed, spatial distribution of deposited particles and, as a consequence, drug efficiency is strongly affected by particle size. Large particles (>6 μm) tend to mainly deposit in the upper airway, limiting the amount of drugs that can be delivered to the lung. Small particles (<2 μm) deposit mainly in the alveolar region and are probably the most apt to act systemically, whereas the particle in the size range 2–6 μm are be best suited to treat the central and small airways. PMID:22686623

  9. Surficial uranium deposits in Somalia

    International Nuclear Information System (INIS)

    Briot, P.

    1984-01-01

    Surficial uranium deposits in Somalia are of the valley-fill calcrete type and occur in the arid Mudugh Province of the Dusa Mareb-El Bur region. They are located in a belt about 240 km in length which is orientated parallel to the north-south regional tectonic framework. The uranium resources of the region amount to about 5,000 t U 3 O 8 at an average grade of 0.1% U 3 O 8 . Basement rocks constitute a 7,000 m thick succession of Jurassic to Quaternary sediments of the Somalian Basin. Uranium mineralization in the form of carnotite occurs in the uppermost Mercia Series. The origin of the uranium and vanadium is unclear due to a shortage of the favourable source rocks. (author)

  10. Carbonaceous deposits on naptha reforming catalysts

    International Nuclear Information System (INIS)

    Redwan, D.S.

    1999-01-01

    Carbonaceous deposits on naphtha reforming catalysts play a decisive role in limiting process performance. The deposits negatively after catalyst activity, selectivity and the production cycle of a semi regenerative reformer. The magnitude of negative effect of those deposits is directly proportional to their amounts and complexity. Investigations on used reforming catalysts samples reveal that the amount and type (complexity of the chemical nature) of carbonaceous deposits are directly proportional to the catalysts life on stream and the severity of operating conditions. In addition, the combustibility behavior of carbonaceous deposits on the catalyst samples taken from different reformers are found to be different. Optimal carbon removal, for in situ catalyst regeneration, requires the specific conditions be developed, based on the results of well designed and properly performed investigations of the amount and type of carbonaceous deposits. (author)

  11. Deposition of aerosol particles in bent pipe

    International Nuclear Information System (INIS)

    Matsui, Hiroshi; Ohhata, Tsutomu

    1989-01-01

    An equation to estimate deposition fraction of aerosol particles in a bent pipe is derived and the validity is verified experimentally. The equation is obtained by assuming that the resultant acceleration of the gravity and the centrifugal force induced in the bend acts on the aerosol particles, and is found to give a relatively accurate estimation of the deposition fraction if a certain correction factor is introduced to the equation. The deposition fraction has a minimum against Reynold number, and the deposition due to centrifugal force dominates at greater Reynolds number than that at the minimum deposition fraction. On the other hand, the smaller the radius of curvature of the bend is, the larger the deposition fraction due to the centrifugal force is. (author)

  12. UFOMOD - atmospheric dispersion and deposition

    International Nuclear Information System (INIS)

    Panitz, H.J.; Matzerath, C.; Paesler-Sauer, J.

    1989-10-01

    The report gives an introduction into the modelling of atmospheric dispersion and deposition which has been implemented in the new program system UFOMOD for assessing the consequences after nuclear accidents. According to the new structure of UFOMOD, different trajectory models with ranges of validity near to the site and at far distances are applied. Emphasis is laid on the description of the segmented plume model MUSEMET and its affilated submodels, being the removal of activity from the cloud by dry and wet deposition, and special effects like plume rise and the behaviour of plumes released into building wakes. In addition, the evaluation of γ-dose correction factors to take account of the finite extent of the radioactive plume in the near range (up to about 20 km) are described. Only brief introductions are given into the principles of the other models available: the puff model RIMPUFF, the long-range puff model MESOS, and the special straight-line Gaussian model ISOLA which are used if low-level long-duration releases are considered. To define starting times of weather sequences and the probabilities of occurrence of these sequences, it is convenient to perform stratified sampling. Therefore, the preprocessing program package METSAM has been developed to perform for generic ACAs a random sampling of weather sequences out off a population of classified weather conditions. The sampling procedure and a detailed input/output (I/O) description is presented and an additional appendix, respectively. A general overview on the I/O structure of MUSEMET as well as a brief user guide to run the KfK version of the MESOS code are also given in the appendix. (orig.) [de

  13. Laboratory Deposition Apparatus to Study the Effects of Wax Deposition on Pipe Magnetic Field Leakage Signals

    Directory of Open Access Journals (Sweden)

    Karim Mohd Fauzi Abd

    2014-07-01

    Full Text Available Accurate technique for wax deposition detection and severity measurement on cold pipe wall is important for pipeline cleaning program. Usually these techniques are validated by conventional techniques on laboratory scale wax deposition flow loop. However conventional techniques inherent limitations and it is difficult to reproduce a predetermine wax deposit profile and hardness at designated location in flow loop. An alternative wax deposition system which integrates modified pour casting method and cold finger method is presented. This system is suitable to reproduce high volume of medium hard wax deposit in pipe with better control of wax deposit profile and hardness.

  14. Acid deposition. Origins, impacts and abatement strategies

    Energy Technology Data Exchange (ETDEWEB)

    Longhurst, J.W.S. (Manchester Polytechnic, Acid Rain Information Centre (United Kingdom). Dept. of Environmental and Geographical Studies) (ed.)

    1991-01-01

    The subject of acid deposition is one of the most important of our contemporary environmental problems. Presenting and discussing new data on the sources and effects of such deposition, this book seeks to assist in the definition of our future research requirements and policy developments. It is divided into four broad themes: Emissions, Chemistry and Deposition, Ecosystem Effects (freshwater, soils and forest systems), Effects on Structural Materials, and Mitigation, Control and Management. (orig.) With 130 figs.

  15. Ion vapor deposition and its application

    International Nuclear Information System (INIS)

    Bollinger, H.; Schulze, D.; Wilberg, R.

    1981-01-01

    Proceeding from the fundamentals of ion vapor deposition the characteristic properties of ion-plated coatings are briefly discussed. Examples are presented of successful applications of ion-plated coatings such as coatings with special electrical and dielectric properties, coatings for corrosion prevention, and coatings for improving the surface properties. It is concluded that ion vapor deposition is an advantageous procedure in addition to vapor deposition. (author)

  16. Surface Finish after Laser Metal Deposition

    Science.gov (United States)

    Rombouts, M.; Maes, G.; Hendrix, W.; Delarbre, E.; Motmans, F.

    Laser metal deposition (LMD) is an additive manufacturing technology for the fabrication of metal parts through layerwise deposition and laser induced melting of metal powder. The poor surface finish presents a major limitation in LMD. This study focuses on the effects of surface inclination angle and strategies to improve the surface finish of LMD components. A substantial improvement in surface quality of both the side and top surfaces has been obtained by laser remelting after powder deposition.

  17. Information problems and deposit constraints at banks

    OpenAIRE

    Jith Jayaratne; Donald Morgan

    1997-01-01

    Following the investment-cash flow literature, we test whether bank lending is constrained by the availability of insured deposits--a necessary condition for the existence of bank lending channel of monetary policy. We treat insured deposits as a type of "internal fund," similar to cash flows. We use a simple model to sort out the possible identification issues in interpreting a lending-deposit correlation, including reverse causality and omitted variable bias. To minimize the latter, we spli...

  18. Restoration of uranium solution mining deposits

    International Nuclear Information System (INIS)

    DeVries, F.W.; Lawes, B.C.

    1981-01-01

    Ammonium carbonates are commonly used as the lixiviant for in-situ leaching of uranium ores. However this leads to the deposition of ammonium ions in the uranium ore formation and the problem of ammonia contamination of ground water which may find its way into the drinking water supply. The ammonia contamination of the ore deposit may be reduced by injecting an aqueous solution of a potassium salt (carbonate, bicarbonate, halide, sulfate, bisulfate, persulfate, or monopersulfate) into the deposit after mining has ceased

  19. A Hierarchical Agency Model of Deposit Insurance

    OpenAIRE

    Jonathan Carroll; Shino Takayama

    2010-01-01

    This paper develops a hierarchical agency model of deposit insurance. The main purpose is to undertake a game theoretic analysis of the consequences of deposit insurance schemes and their effects on monitoring incentives for banks. Using this simple framework, we analyze both risk- independent and risk-dependent premium schemes along with reserve requirement constraints. The results provide policymakers with not only a better understanding of the effects of deposit insurance on welfare and th...

  20. Urban acid deposition in Greater Manchester

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D.S.; Longhurst, J.W.S.; Gee, D.R.; Hare, S.E. (Manchester Polytechnic, Manchester (UK). Acid Rain Information Centre)

    1989-08-01

    Data are presented from a monitoring network of 18 bulk precipitation collectors and one wet-only collector in the urban area of Greater Manchester, in the north west of England. Weekly samples were analysed for all the major ions in precipitation along with gaseous nitrogen dioxide concentrations from diffusion tubes. Statistical analysis of the data shows significant spatial variation of non marine sulphate, nitrate, ammonium, acidity and calcium concentrations, and nitrogen dioxide concentrations. Calcium is thought to be responsible for the buffering of acidity and is of local origin. Wet deposition is the likely removal process for calcium in the atmosphere and probably by below cloud scavenging. Nitrate and ammonium concentrations and depositions show close spatial, temporal and statistical association. Examination of high simultaneous episodes of nitrate and ammonium deposition shows that these depositions cannot be explained in terms of trajectories and it is suggested that UK emissions of ammonia may be important. Statistical analysis of the relationships between nitrate and ammonium depositions, concentrations and precipitation amount suggest that ammonia from mesoscale sources reacts reversibly with nitric acid aerosol and is removed by below cloud scavenging. High episodes of the deposition of non marine sulphate are difficult to explain by trajectory analysis alone, perhaps suggesting local sources. In a comparison between wet deposition and bulk deposition, it was shown that only 15.2% of the non marine sulphur was dry deposited to the bulk precipitation collector. 63 refs., 86 figs., 31 tabs.

  1. Uraniferous surficial deposits in Southern Africa

    International Nuclear Information System (INIS)

    Hambleton-Jones, B.B.; Levin, M.; Wagener, G.F.

    1986-01-01

    Surficial uranium deposits are located in the north-western Cape Province of South Africa, in the Namib Desert east of Walvis Bay in South West Africa/Namibia and in the Serule Block of Botswana. They have been classified into the valley-fill, lacustrine, and pedogenic types. Carnotite is the main uranium-bearing mineral in the larger surficial deposits, with other minerals such as soddyite and phosphuranylite occurring locally. Uraninite or urano-organic complexes occur in the reducing environments of the diatomaceous earth, peat-rich deposits. Economically, the valley-fill type is the most important, with the largest deposits occurring in South West Africa/Namibia. In South West Africa/Namibia the valley-fill surficial uranium deposits occur in the Tumas and Langer Heinrich formations of the Teriary to Recent Namib Group. The Tubas, Langer Heinrich, and Welwitchia deposits are discussed: in them, carnotite occurs in calcareous and gypsiferous fluvial gravels. The pedogenic deposit at Mile 72 occurs in weathered granite and overlying gypcrete and has little economic potential. The economic potential of the surficial deposits in the north-western Cape Province is very limited in comparison with their South West African/Namibian counterparts, but the most important deposits are the lacustrine type, in particular those containing peat and diatomaceous earth. The mechanisms for the precipitation and preservation of the uranium are discussed

  2. Deposition of corrosion products in-core

    International Nuclear Information System (INIS)

    Burrill, K.A.

    1994-11-01

    Data on corrosion product deposits on fuel sheaths are presented for a variety of operating conditions and water chemistries: boiling and non-boiling water; surface heat flux; pH, dissolved hydrogen concentration. Corrosion product behaviour in-core may be interpreted in terms of the solubility of magnetite and how it changes with water chemistry and temperature. A hypothesis of the deposition and release mechanisms was proposed in the 1970s in which particles deposited onto the sheath and subsequently dissolved in the heated water while being irradiated. Some of the deposition data may be interpreted using a model of these mechanisms. (author). 5 refs., 6 tabs., 8 figs

  3. Worldwide deposition of 90Sr through 1984

    International Nuclear Information System (INIS)

    Larsen, R.J.; Juzdan, Z.R.

    1986-10-01

    The deposition of 90 Sr in the Northern Hemisphere during 1984 was 0.3 PBq (0.008 MCi), while that of the Southern Hemisphere was 0.1 PBq (0.003 MCi). This resulted in a total deposition on the surface of the earth during 1984 of 0.4 PBq (0.011 MCi). This is the lowest total yearly deposit since the initiation of the Environmental Measurements Laboratory's global fallout program in the mid-1950's. The worldwide cumulative deposit decreased to 357 PBq (9.6 MCi)

  4. Low-fluorine Stockwork Molybdenite Deposits

    Science.gov (United States)

    Ludington, Steve; Hammarstrom, Jane; Piatak, Nadine M.

    2009-01-01

    Low-fluorine stockwork molybdenite deposits are closely related to porphyry copper deposits, being similar in their tectonic setting (continental volcanic arc) and the petrology (calc-alkaline) of associated igneous rock types. They are mainly restricted to the Cordillera of western Canada and the northwest United States, and their distribution elsewhere in the world may be limited. The deposits consist of stockwork bodies of molybdenite-bearing quartz veinlets that are present in and around the upper parts of intermediate to felsic intrusions. The deposits are relatively low grade (0.05 to 0.2 percent Mo), but relatively large, commonly >50 million tons. The source plutons for these deposits range from granodiorite to granite in composition; the deposits primarily form in continental margin subduction-related magmatic arcs, often concurrent with formation of nearby porphyry copper deposits. Oxidation of pyrite in unmined deposits or in tailings and waste rock during weathering can lead to development of acid-rock drainage and limonite-rich gossans. Waters associated with low-fluorine stockwork molybdenite deposits tend to be nearly neutral in pH; variable in concentrations of molybdenum (10,000 ug/L); below regulatory guidelines for copper, iron, lead, zinc, and mercury; and locally may exceed guidelines for arsenic, cadmium, and selenium.

  5. Structural characterization of MAPLE deposited lipase biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

    2014-11-30

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

  6. Spray deposition using impulse atomization technique

    International Nuclear Information System (INIS)

    Ellendt, N.; Schmidt, R.; Knabe, J.; Henein, H.; Uhlenwinkel, V.

    2004-01-01

    A novel technique, impulse atomization, has been used for spray deposition. This single fluid atomization technique leads to different spray characteristics and impact conditions of the droplets compared to gas atomization technique which is the common technique used for spray deposition. Deposition experiments with a Cu-6Sn alloy were conducted to evaluate the appropriateness of impulse atomization to produce dense material. Based on these experiments, a model has been developed to simulate the thermal history and the local solidification rates of the deposited material. A numerical study shows how different cooling conditions affect the solidification rate of the material

  7. Análise da co-utilização do resíduo do beneficiamento do caulim e serragem de granito para produção de blocos e telhas cerâmicos Analysis of the use of kaolin processing waste and granite sawing waste together for the production of ceramic bricks and roof tiles

    Directory of Open Access Journals (Sweden)

    R. R. Menezes

    2007-06-01

    Full Text Available O volume de resíduos gerado pela mineração e o beneficiamento mineral vêm se intensificando a cada dia, em virtude do aumento da demanda causado pelo crescimento da economia mundial. As indústrias do beneficiamento do caulim e da serragem do granito são importantes segmentos econômicos do Estado da Paraíba, entretanto produzem enormes quantidades de resíduos. Assim, este trabalho tem por objetivo caracterizar os resíduos do beneficiamento do caulim e da serragem do granito e avaliar a viabilidade de sua co-utilização para produção de blocos e telhas cerâmicos. Os resíduos foram caracterizados através da determinação de sua composição química e mineralógica, pelo uso de difração de raios X e análise térmica diferencial e gravimétrica, distribuição e tamanho de partículas e análise morfológica por microscopia eletrônica de varredura. Foram formuladas composições contendo os resíduos e confeccionados corpos de prova por extrusão. Os corpos de prova foram queimados e em seguida determinou-se sua absorção de água e módulo de ruptura à flexão. Pode-se observar que o resíduo do caulim é constituído por caulinita, mica e quartzo, que o resíduo de granito é constituído por quartzo, mica, albita e calcita e, que os resíduos apresentam distribuições granulométricas significativamente diferentes. Concluiu-se também que é possível a incorporação de até 50% de resíduo em formulações para produção de blocos e telhas cerâmicas e que a co-utilização do resíduo de granito e de caulim possibilita obter propriedades físicas superiores às observadas nos corpos de prova com incorporação de apenas resíduo de caulim.The amount of wastes generated by the miner and mineral processing industries has increasing day by day due to the high demand cause by the global economy grow up. The processing kaolin ad sawing granite industries are important economic segments in the state of Paraíba, but generate

  8. Tungsten Deposition on Graphite using Plasma Enhanced Chemical Vapour Deposition

    International Nuclear Information System (INIS)

    Sharma, Uttam; Chauhan, Sachin S; Sharma, Jayshree; Sanyasi, A K; Ghosh, J; Choudhary, K K; Ghosh, S K

    2016-01-01

    The tokamak concept is the frontrunner for achieving controlled thermonuclear reaction on earth, an environment friendly way to solve future energy crisis. Although much progress has been made in controlling the heated fusion plasmas (temperature ∼ 150 million degrees) in tokamaks, technological issues related to plasma wall interaction topic still need focused attention. In future, reactor grade tokamak operational scenarios, the reactor wall and target plates are expected to experience a heat load of 10 MW/m 2 and even more during the unfortunate events of ELM's and disruptions. Tungsten remains a suitable choice for the wall and target plates. It can withstand high temperatures, its ductile to brittle temperature is fairly low and it has low sputtering yield and low fuel retention capabilities. However, it is difficult to machine tungsten and hence usages of tungsten coated surfaces are mostly desirable. To produce tungsten coated graphite tiles for the above-mentioned purpose, a coating reactor has been designed, developed and made operational at the SVITS, Indore. Tungsten coating on graphite has been attempted and successfully carried out by using radio frequency induced plasma enhanced chemical vapour deposition (rf -PECVD) for the first time in India. Tungsten hexa-fluoride has been used as a pre-cursor gas. Energy Dispersive X-ray spectroscopy (EDS) clearly showed the presence of tungsten coating on the graphite samples. This paper presents the details of successful operation and achievement of tungsten coating in the reactor at SVITS. (paper)

  9. Hideout in steam generator tube deposits

    International Nuclear Information System (INIS)

    Balakrishnan, P.V.; Franklin, K.J.; Turner, C.W.

    1998-05-01

    Hideout in deposits on steam generator tubes was studied using tubes coated with magnetite. Hideout from sodium chloride solutions at 279 degrees C was followed using an on-line high-temperature conductivity probe, as well as by chemical analysis of solution samples from the autoclave in which the studies were done. Significant hideout was observed only at a heat flux greater than 200 kW/m 2 , corresponding to a temperature drop greater than 2 degrees C across the deposits. The concentration factor resulting from the hideout increased highly non-linearly with the heat flux (varying as high as the fourth power of the heat flux). The decrease in the apparent concentration factor with increasing deposit thickness suggested that the pores in the deposit were occupied by a mixture of steam and water, which is consistent with the conclusion from the thermal conductivity measurements on deposits in a separate study. Analyses of the deposits after the hideout tests showed no evidence of any hidden-out solute species, probably due to the concentrations being very near the detection limits and to their escape from the deposit as the tests were being ended. This study showed that hideout in deposits may concentrate solutes in the steam generator bulk water by a factor as high as 2 x 10 3 . Corrosion was evident under the deposit in some tests, with some chromium enrichment on the surface of the tube. Chromium enrichment usually indicates an acidic environment, but the mobility required of chromium to become incorporated into the thick magnetite deposit may indicate corrosion under an alkaline environment. An alkaline environment could result from preferential accumulation of sodium in the solution in the deposit during the hideout process. (author)

  10. Regional aerosol deposition in human upper airways

    International Nuclear Information System (INIS)

    Swift, D.L.

    1989-01-01

    During the report period significant progress on the quantitative understanding of regional upper airway deposition of airborne particle has been realized. Replicate models of the human upper airways obtained from post-mortem casting of the nasal, oral, pharyngeal, laryngeal and upper tracheal regions and in vivo magnetic resonance imaging (MRI) of the same regions of adults and children have been employed to determine the overall and local deposition characteristics of aerosols in the ultrafine (1--100 μm diameter) and fine (0.8--12 μm diameter) region. Studies have been carried out for both nasal and oral breathing during inspiratory and expiratory flow at constant flow rates representative of rest and states of exercise. The results of these investigations indicate that particles in the size range of ''unattached'' radon progeny (1--3 nm) are deposited in both the nasal and oral passages with high efficiency (60--80%) for both inspiration and expiration, with the nasal deposition being somewhat greater (5--10%) than oral deposition. The effect of flow rate on upper airway deposition for both pathways is not great; data analysis indicates that the deposition for all flow rates from 4--50 liters/minute can be grouped by plotting deposition vs Q- 1/8 , where Q is flow rate, a far weaker dependency than observed for inertial deposition. Diffusional transport is the primary mechanism of deposition, and size dependence can be accounted for by plotting, deposition percent vs D n where D is particle diffusion coefficient and n ranges from 0.5--0.66. 2 refs

  11. Pulsed laser deposition in Twente: from research tool towards industrial deposition

    NARCIS (Netherlands)

    Blank, David H.A.; Dekkers, Jan M.; Rijnders, Augustinus J.H.M.

    2014-01-01

    After the discovery of the perovskite high Tc superconductors in 1986, a rare and almost unknown deposition technique attracted attention. Pulsed laser deposition (PLD), or laser ablation as it was called in the beginning, became popular because of the possibility to deposit complex materials, like

  12. Patterned deposition by atmospheric pressure plasma-enhanced spatial atomic layer deposition

    NARCIS (Netherlands)

    Poodt, P.; Kniknie, B.J.; Branca, A.; Winands, G.J.J.; Roozeboom, F.

    2011-01-01

    An atmospheric pressure plasma enhanced atomic layer deposition reactor has been developed, to deposit Al2O3 films from trimethyl aluminum and an He/O2 plasma. This technique can be used for 2D patterned deposition in a single in-line process by making use of switched localized plasma sources. It

  13. DepositScan, a Scanning Program to Measure Spray Deposition Distributions

    Science.gov (United States)

    DepositScan, a scanning program was developed to quickly measure spray deposit distributions on water sensitive papers or Kromekote cards which are widely used for determinations of pesticide spray deposition quality on target areas. The program is installed in a portable computer and works with a ...

  14. Global reactive nitrogen deposition from lightning NOx

    NARCIS (Netherlands)

    Shepon, A.; Gildor, H.; Labrador, L.J.; Butler, T.; Ganzeveld, L.N.; Lawrence, M.G.

    2007-01-01

    We present results of the deposition of nitrogen compounds formed from lightning (LNO x ) using the global chemical transport Model of Atmospheric Transport and Chemistry¿Max Planck Institute for Chemistry version. The model indicates an approximately equal deposition of LNO x in both terrestrial

  15. Assessment of Global Mercury Deposition through Litterfall.

    Science.gov (United States)

    Wang, Xun; Bao, Zhengduo; Lin, Che-Jen; Yuan, Wei; Feng, Xinbin

    2016-08-16

    There is a large uncertainty in the estimate of global dry deposition of atmospheric mercury (Hg). Hg deposition through litterfall represents an important input to terrestrial forest ecosystems via cumulative uptake of atmospheric Hg (most Hg(0)) to foliage. In this study, we estimate the quantity of global Hg deposition through litterfall using statistical modeling (Monte Carlo simulation) of published data sets of litterfall biomass production, tree density, and Hg concentration in litter samples. On the basis of the model results, the global annual Hg deposition through litterfall is estimated to be 1180 ± 710 Mg yr(-1), more than two times greater than the estimate by GEOS-Chem. Spatial distribution of Hg deposition through litterfall suggests that deposition flux decreases spatially from tropical to temperate and boreal regions. Approximately 70% of global Hg(0) dry deposition occurs in the tropical and subtropical regions. A major source of uncertainty in this study is the heterogeneous geospatial distribution of available data. More observational data in regions (Southeast Asia, Africa, and South America) where few data sets exist will greatly improve the accuracy of the current estimate. Given that the quantity of global Hg deposition via litterfall is typically 2-6 times higher than Hg(0) evasion from forest floor, global forest ecosystems represent a strong Hg(0) sink.

  16. Plant responses to insect egg deposition

    NARCIS (Netherlands)

    Hilker, M.; Fatouros, N.E.

    2015-01-01

    Plants can respond to insect egg deposition and thus resist attack by herbivorous insects from the beginning of the attack, egg deposition. We review ecological effects of plant responses to insect eggs and differentiate between egg-induced plant defenses that directly harm the eggs and indirect

  17. Genetic types of uranium deposits of Ukraine

    International Nuclear Information System (INIS)

    Anysimov, V.A.

    1997-01-01

    There are three genetic classes of uranium deposits in Ukraine. Eight types of uranium deposits are described with reference to their genesis, age and geological position. The attributes of uranium concentration in Precambrian and Proterozoic periods of activization are shown. (author). 1 fig., 1 tab

  18. On the Tengiz petroleum deposit previous study

    International Nuclear Information System (INIS)

    Nysangaliev, A.N.; Kuspangaliev, T.K.

    1997-01-01

    Tengiz petroleum deposit previous study is described. Some consideration about structure of productive formation, specific characteristic properties of petroleum-bearing collectors are presented. Recommendation on their detail study and using of experience on exploration and development of petroleum deposit which have analogy on most important geological and industrial parameters are given. (author)

  19. Regional aerosol deposition in human upper airways

    Energy Technology Data Exchange (ETDEWEB)

    Swift, D.L.

    1991-11-01

    During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po{sup 218} particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po{sup 218} particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po{sup 218} particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig.

  20. Uranium deposits of Australia to 1975

    International Nuclear Information System (INIS)

    Spannari, S.

    1979-01-01

    This bibliography provides a retrospective account of Australian uranium deposits, particularly the unpublished materials in the Australian Capital Territory. Some abstracts are included. Occurrences, mineralogy, ore genesis, structural controls and the eonomic geology of uranium deposits are covered but the mining of uranium, exploration reports, surveys, environmental aspects and controversial materials are not

  1. Regional aerosol deposition in human upper airways

    International Nuclear Information System (INIS)

    Swift, D.L.

    1991-01-01

    During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po 218 particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po 218 particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po 218 particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig

  2. 49 CFR 386.46 - Depositions.

    Science.gov (United States)

    2010-10-01

    ..., INTERMODAL EQUIPMENT PROVIDER, BROKER, FREIGHT FORWARDER, AND HAZARDOUS MATERIALS PROCEEDINGS General Rules... to referral to the Office of Hearings, a party may petition the Assistant Administrator, in accordance with § 386.37, for leave to conduct a deposition based on good cause shown. (2) Depositions may be...

  3. 37 CFR 1.25 - Deposit accounts.

    Science.gov (United States)

    2010-07-01

    ... ordering services offered by the Office, copies of records, etc., deposit accounts may be established in... receipt of the statement to cover the value of items or services charged to the account and thus restore..., copies, etc., requested must always be on deposit. Charges to accounts with insufficient funds will not...

  4. 37 CFR 2.208 - Deposit accounts.

    Science.gov (United States)

    2010-07-01

    ... copies of records, or services offered by the Office, deposit accounts may be established in the Office... upon receipt of the statement to cover the value of items or services charged to the account and thus... services requested must always be on deposit. Charges to accounts with insufficient funds will not be...

  5. Ammonia release method for depositing metal oxides

    Energy Technology Data Exchange (ETDEWEB)

    Silver, G.L.; Martin, F.S.

    1993-12-31

    A method of depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates.

  6. 12 CFR 337.6 - Brokered deposits.

    Science.gov (United States)

    2010-01-01

    ... government sponsored minority or women-owned depository institution deposit program. (iii) Notwithstanding... any brokered deposit without restriction by this section. (2)(i) An adequately capitalized insured... restriction on the payment of interest contained in paragraph (b)(2)(ii) of the section. After such 90-day...

  7. Atomic layer deposition for graphene device integration

    NARCIS (Netherlands)

    Vervuurt, R.H.J.; Kessels, W.M.M.; Bol, A.A.

    2017-01-01

    Graphene is a two dimensional material with extraordinary properties, which make it an interesting material for many optical and electronic devices. The integration of graphene in these devices often requires the deposition of thin dielectric layers on top of graphene. Atomic layer deposition (ALD)

  8. Excimer Laser Deposition of PLZT Thin Films

    National Research Council Canada - National Science Library

    Petersen, GAry

    1991-01-01

    .... In order to integrate these devices into optical systems, the production of high quality thin films with high transparency and perovskite crystal structure is desired. This requires development of deposition technologies to overcome the challenges of depositing and processing PLZT thin films.

  9. Direct uptake by vegetation of deposited materials

    International Nuclear Information System (INIS)

    Eriksson, Aa.

    1977-01-01

    Interception and retention in pasture grass of nuclides in ionic form and of labelled particles (40-63, 63-100, 100-200 μ in size) were studied experimentally during 1968-70. The results obtained are compared with data from grazing experiments during 1970-72. The data showed that the relative amount of material intercepted by the vegetation decreased markedly in the following order: wet-deposited nuclides > wet-deposited particles > particles dry-deposited on grass wet rain > particles dry-deposited on grass superficially wet > particles dry-deposited on dry grass, and small particles > larger particles. At high relative humidity of the air much more of a deposition could be intercepted than at low relative humidity. The retention of intercepted material was influenced by type of material and by precipitation. Intense rains shortened the half residence time considerably. Dry-deposited materials intercepted in grass suffered marked losses by falloff during the first few days after deposition, which was followed by a phase with a longer half residence time. (author)

  10. Goudafzettingen in Suriname (Gold deposits in Surinam)

    NARCIS (Netherlands)

    Brinck, J.W.

    1956-01-01

    THE GOLD DEPOSITS IN SURINAM AND THE DISTRIBUTION OF CONCESSIONS THROUGH THE COUNTRY The fieldwork on the occurrence of primary and secondary gold deposits in Surinam on which this thesis is based was carried out by order of the Welfare Fund Surinam (Welvaarts Fonds Suriname) during the periods

  11. Depositional environment and provenance of Middle Siwalik ...

    Indian Academy of Sciences (India)

    The sedimentary facies and facies associations within the lithostratigraphic column of the Middle Siwalik rocks show temporal repetition of sedimentary facies associations suggesting oscillation between proximal-, mid- and distal fan setups within a palaeo-alluvial fan depositional environment similar to the depositional ...

  12. Energy deposition in NSRR test fuels

    International Nuclear Information System (INIS)

    Ohnishi, Nobuaki; Tanzawa, Sadamitsu; Tanzawa, Tomio; Kitano, Teruaki; Okazaki, Shuji

    1978-02-01

    Interpretation of fuel performance data collected during inpile testing in the NSRR requires a knowledge of the energy deposition or enthalpy increase in each sample tested. The report describes the results of absolute measurement of fission products and contents of uranium in irradiated test fuels which were performed to determine the energy deposition. (auth.)

  13. Time Resolved Deposition Measurements in NSTX

    International Nuclear Information System (INIS)

    Skinner, C.H.; Kugel, H.; Roquemore, A.L.; Hogan, J.; Wampler, W.R.

    2004-01-01

    Time-resolved measurements of deposition in current tokamaks are crucial to gain a predictive understanding of deposition with a view to mitigating tritium retention and deposition on diagnostic mirrors expected in next-step devices. Two quartz crystal microbalances have been installed on NSTX at a location 0.77m outside the last closed flux surface. This configuration mimics a typical diagnostic window or mirror. The deposits were analyzed ex-situ and found to be dominantly carbon, oxygen, and deuterium. A rear facing quartz crystal recorded deposition of lower sticking probability molecules at 10% of the rate of the front facing one. Time resolved measurements over a 4-week period with 497 discharges, recorded 29.2 (micro)g/cm 2 of deposition, however surprisingly, 15.9 (micro)g/cm 2 of material loss occurred at 7 discharges. The net deposited mass of 13.3 (micro)g/cm 2 matched the mass of 13.5 (micro)g/cm 2 measured independently by ion beam analysis. Monte Carlo modeling suggests that transient processes are likely to dominate the deposition

  14. The geomicrobiology of bauxite deposits

    Directory of Open Access Journals (Sweden)

    Xiluo Hao

    2010-10-01

    Full Text Available Bauxite deposits are studied because of their economic value and because they play an important role in the study of paleoclimate and paleogeography of continents. They provide a rare record of the weathering and evolution of continental surfaces. Geomicrobiological analysis makes it possible to verify that microorganisms have played a critical role during the formation of bauxite with the possibility already intimated in previous studies. Ambient temperature, abundance of water, organic carbon and bioavailable iron and other metal substrates provide a suitable environment for microbes to inhabit. Thiobacillus, Leptospirilum, Thermophilic bacteria and Heterotrophs have been shown to be able to oxidize ferrous iron and to reduce sulfate-generating sulfuric acid, which can accelerate the weathering of aluminosilicates and precipitation of iron oxyhydroxides. Microorganisms referred to the genus Bacillus can mediate the release of alkaline metals. Although the dissimilatory iron-reducing and sulfate-reducing bacteria in bauxites have not yet been identified, some recorded authigenic carbonates and “bacteriopyrites” that appear to be unique in morphology and grain size might record microbial activity. Typical bauxite minerals such as gibbsite, kaolinite, covellite, galena, pyrite, zircon, calcium plagioclase, orthoclase, and albite have been investigated as part of an analysis of microbial mediation. The paleoecology of such bauxitic microorganisms inhabiting continental (sub surfaces, revealed through geomicrobiological analysis, will add a further dimension to paleoclimatic and paleoenvironmental studies.

  15. Aquatic chemistry of acid deposition

    Energy Technology Data Exchange (ETDEWEB)

    Stumm, W; Sigg, L; Schnoor, J L

    1987-01-01

    The occurrence of acid precipitation in many regions of the Northern hemisphere is a consequnece of human interference in the cycles that unite land, water and atmosphere. The oxidation of carbon, sulfur and nitrogen, resulting mostly from fossil fuel burning, rivals oxidation processes induced by photosynthesis and respiration and disturbs redox conditions in the atmosphere. The paper discusses oxidation-reduction reactions, particularly those involving atmospheric pollutants that are important in the formation of acid precipitation. Topics covered are: a stoichiometric model of acid rain formation; sulfur dioxide and ammonia adsorption; acid neutralizing capacity. The paper concludes that explanations of simple chemical equilibria between gases and water aid our understanding of how acidifying gases become dissolved in cloud water, in droplets of falling rain, or in fog. Rigorous definitions of base- or acid-neutralizing capacities are prerequisites to measuring and interpreting residual acidity in dry and wet deposition and for assessing the disturbance caused by the transfer of acid to terrestrial and aquatic ecosystems. 20 references.

  16. Biosensor Applications of MAPLE Deposited Lipase

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2014-10-01

    Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique derived from Pulsed Laser Deposition (PLD for deposition of delicate (polymers, complex biological molecules, etc. materials in undamaged form. The main difference of MAPLE technique with respect to PLD is the target: it is a frozen solution or suspension of the (guest molecules to be deposited in a volatile substance (matrix. Since laser beam energy is mainly absorbed by the matrix, damages to the delicate guest molecules are avoided, or at least reduced. Lipase, an enzyme catalyzing reactions borne by triglycerides, has been used in biosensors for detection of β-hydroxyacid esters and triglycerides in blood serum. Enzymes immobilization on a substrate is therefore required. In this paper we show that it is possible, using MAPLE technique, to deposit lipase on a substrate, as shown by AFM observation, preserving its conformational structure, as shown by FTIR analysis.

  17. Oxide cathodes produced by plasma deposition

    International Nuclear Information System (INIS)

    Scheitrum, G.; Caryotakis, G.; Pi, T.; Umstattd, R.; Brown, I.; Montiero, O.

    1997-01-01

    These are two distinct applications for high-current-density, long-life thermionic cathodes. The first application is as a substitute for explosive emission cathodes used in high-power microwave (HPM) devices being developed for Air Force programs. The second application is in SLAC's X-band klystrons for the Next Linear Collider (NLC). SLAC, UCD, and LBL are developing a plasma deposition process that eliminates the problems with binders, carbonate reduction, peeling, and porosity. The emission layer is deposited using plasma deposition of metallic barium in vacuum with an oxygen background gas. An applied bias voltage drives the oxide plasma into the nickel surface. Since the oxide is deposited directly, it does not have problems with poisoning from a hydrocarbon binder. The density of the oxide layer is increased from the 40--50% for standard oxide cathodes to nearly 100% for plasma deposition

  18. Uranium ore deposits: geology and processing implications

    International Nuclear Information System (INIS)

    Belyk, C.L.

    2010-01-01

    There are fifteen accepted types of uranium ore deposits and at least forty subtypes readily identified around the world. Each deposit type has a unique set of geological characteristics which may also result in unique processing implications. Primary uranium production in the past decade has predominantly come from only a few of these deposit types including: unconformity, sandstone, calcrete, intrusive, breccia complex and volcanic ones. Processing implications can vary widely between and within the different geological models. Some key characteristics of uranium deposits that may have processing implications include: ore grade, uranium and gangue mineralogy, ore hardness, porosity, uranium mineral morphology and carbon content. Processing difficulties may occur as a result of one or more of these characteristics. In order to meet future uranium demand, it is imperative that innovative processing approaches and new technological advances be developed in order that many of the marginally economic traditional and uneconomic non-traditional uranium ore deposits can be exploited. (author)

  19. Laser-induced chemical vapor deposition reactions

    International Nuclear Information System (INIS)

    Teslenko, V.V.

    1990-01-01

    The results of investigation of chemical reactions of deposition of different substances from the gas phase when using the energy of pulse quasicontinuous and continuous radiation of lasers in the wave length interval from 0.193 to 10.6 μm are generalized. Main attetion is paid to deposition of inorganic substances including nonmetals (C, Si, Ge and others), metals (Cu, Au, Zn, Cd, Al, Cr, Mo, W, Ni) and some simple compounds. Experimental data on the effect of laser radiation parameters and reagent nature (hydrides, halogenides, carbonyls, alkyl organometallic compounds and others) on the deposition rate and deposit composition are described in detail. Specific features of laser-chemical reactions of deposition and prospects of their application are considered

  20. A lithium deposition system for tokamak devices*

    Science.gov (United States)

    Graziul, Christopher; Majeski, Richard; Kaita, Robert; Hoffman, Daniel; Timberlake, John; Card, David

    2002-11-01

    The production of a lithium deposition system using commercially available components is discussed. This system is intended to provide a fresh lithium wall coating between discharges in a tokamak. For this purpose, a film 100-200 Å thick is sufficient to ensure that the plasma interacts solely with the lithium. A test system consisting of a lithium evaporator and a deposition monitor has been designed and constructed to investigate deposition rates and coverage. A Thermionics 3kW e-gun is used to rapidly evaporate small amounts of solid lithium. An Inficon XTM/2 quartz deposition monitor then measures deposition rate at varying distances, positions and angles relative to the e-gun crucible. Initial results from the test system will be presented. *Supported by US DOE contract #DE-AC02-76CH-03073