292 research outputs found
Hydrotalcites: A Highly Efficient Ecomaterial For Effluent Treatment Originated From Carbon Nanotubes Chemical Processing
It has been reported that a mixture of carboxylated carbonaceous fragments (CCFs), so called oxidation debris, are generated during carbon nanotubes chemical processing using oxidant agents such as HNO3. The elimination of these fragments from carbon nanotubes surface has been point out to be a crucial step for an effective functionalization of the nanotubes as well as for improving the material. However, this process can introduce a potential environmental problem related water contamination because these CCFs can be viewed as a mixture of carbonaceous polyaromatic systems similar to humic substances and dissolved organic matter (DOM). The negative aspects of humic substances and DOM to water quality and wastewater treatment are well known. Since carbon nanotubes industry expands at high rates it is expected that effluent containing oxidation debris will increase since HNO3 chemical processing is the most applied method for purification and functionalization of carbon nanotubes. In this work, we have demonstrated that Hydrotalcites (HT) are highly efficient to remove oxidation debris from effluent solution originated from HNO3-treated multiwalled carbon nanotubes. The strategy presented here is a contribution towards green chemistry practices and life cycle studies in carbon nanotubes field.3041Albrecht, M.A., Evans, C.W., Raston, C.L., Green chemistry and the health implications of nanoparticles (2006) Green Chem., 8, pp. 417-432Datsyuk, V., Kalyva, M., Papagelis, K., Parthenios, J., Tasis, D., Siokou, A., Kallitsis, I., Galiotis, C., Chemical oxidation of multiwalled carbon nanotubes (2008) Carbon, 46, pp. 833-840Salzmann, C.G., Llewellyn, S.A., Tobias, G., Ward, M.A., Huh, Y., Green, M.L.H., The role of carboxylated carbonaceous fragments in the functionalization and spectroscopy of a single-walled carbon-nanotube material (2007) Advanced Materials, 19, pp. 883-887Fogden, S., Verdejo, R., Cottam, B., Shaffer, M., Purification of single walled carbon nanotubes: The problem with oxidation debris (2008) Chem. Phys. Lett., 460, pp. 162-167Verdejo, R., Lamoriniere, S., Cottam, B., Bismarck, A., Shaffer, M., Removal of oxidation debris from multi-walled carbon nanotubes (2007) Chem. Commun., pp. 513-515Yu, H., Jin, Y.G., Peng, F., Wang, H.J., Yang, J., Kinetically controlled side-wall functionalization of carbon nanotubes by nitric acid oxidation (2008) J. Phys. Chem., 112, pp. 6758-6763Worsley, K.A., Kalinina, I., Bekyarova, E., Haddon, R.C., Functionalization and Dissolution of Nitric Acid Treated Single-Walled Carbon Nanotubes (2009) J. the American Chem. Society, 131, pp. 18153-18158Wang, Z., Korobeinyk, A., Whitby, R.L.D., Meikle, S.T., Mikhalovsky, S.V., Acquah, S.F.A., Kroto, H.W., Direct confirmation that carbon nanotubes still react covalently after removal of acid-oxidative lattice fragments (2010) Carbon, 48, pp. 916-918Liang, L., Singer, P.C., Factors influencing the formation and relative distribution of haloacetic acids and trihalomethanes in drinking water (2003) Environmental Sci. Technol., 37, pp. 2920-2928Nikolaou, A.D., Golfinopoulos, S.K., Lekkas, T.D., Kostopoulou, M.N., DBP levels in chlorinated drinking water: Effect of humic substances (2004) Environmental Monitoring Assessment, 93, pp. 301-319Chien, S.W.C., Wang, M.C., Huang, C.C., Reactions of compost-derived humic substances with lead, copper, cadmium, and zinc (2006) Chemosphere, 64, pp. 1353-1361Garbin, J.R., Milori, D.M.B.P., Simoes, M.L., Da Silva, W.T.L., Neto, L.M., Influence of humic substances on the photolysis of aqueous pesticide residues (2007) Chemosphere, 66, pp. 1692-1698Durjava, M.K., Ter Laak, T.L., Hermens, J.L.M., Struijs, J., Distribution of PAHs and PCBs to dissolved organic matter: High distribution coefficients with consequences for environmental fate modeling (2007) Chemosphere, 67, pp. 990-997Oh, J.M., Biswick, T.T., Choy, J.H., Layered nanomaterials for green materials (2009) J. Materials Chem., 19, pp. 2553-2563Ferreira, O.P., Alves, O.L., MacEdo, J.D., Gimenez, I.D., Barreto, L.S., Ecomaterials: Development and application of functional porous materials for environmental protection (2007) Quimica Nova, 30, pp. 464-467Ferreira, O.P., De Moraes, S.G., Duran, N., Cornejo, L., Alves, O.L., Evaluation of boron removal from water by hydrotalcite-like compounds (2006) Chemosphere, 62, pp. 80-88Goh, K.H., Lim, T.T., Dong, Z.L., Enhanced Arsenic Removal by Hydrothermally Treated Nanocrystalline Mg/Al Layered Double Hydroxide with Nitrate Intercalation (2009) Environmental Sci. Technol., 43, pp. 2537-2543Helland, A., Scheringer, M., Siegris, M., Kastenholz, H.G., Wiek, A., Scholz, R.W., Risk assessment of engineered nanomaterials: A survey of industrial approaches (2008) Environmental Sci. Technol., 42, pp. 640-646Meyer, D.E., Curran, M.A., Gonzalez, M.A., An Examination of Existing Data for the Industrial Manufacture and Use of Nanocomponents and Their Role in the Life Cycle Impact of Nanoproducts (2009) Environmental Sci. Technol., 43, pp. 1256-1263Dillon, A.C., Gennett, T., Jones, K.M., Alleman, J.L., Parilla, P.A., Heben, M.J., A simple and complete purification of single-walled carbon nanotube materials (1999) Advanced Materials, 11, pp. 1354-1358Shao, L., Tobias, G., Salzmann, C.G., Ballesteros, B., Hong, S.Y., Crossley, A., Davis, B.G., Green, M.L.H., Removal of amorphous carbon for the efficient sidewall functionalisation of single-walled carbon nanotubes (2007) Chem. Commun., pp. 5090-5092Tobias, G., Shao, L.D., Ballesteros, B., Green, M.L.H., Enhanced Sidewall Functionalization of Single-Wall Carbon Nanotubes Using Nitric Acid (2009) J. Nanoscience Nanotechnology, 9, pp. 6072-6077Wang, Z.W., Shirley, M.D., Meikle, S.T., Whitby, R.L.D., Mikhalovsky, S.V., The surface acidity of acid oxidised multi-walled carbon nanotubes and the influence of in-situ generated fulvic acids on their stability in aqueous dispersions (2009) Carbon, 47, pp. 73-79Seida, Y., Nakano, Y., Removal of humic substances by layered double hydroxide containing iron (2000) Water Research, 34, pp. 1487-1494Goh, K.H., Lim, T.T., Dong, Z., Application of layered double hydroxides for removal of oxyanions: A review (2008) Water Research, 42, pp. 1343-1368Rocha, J., Del Arco, M., Rives, V., Ulibarri, M.A., Reconstruction of layered double hydroxides from calcined precursors: A powder XRD and Al-27 MAS NMR study (1999) J. Materials Chem., 9, pp. 2499-2503Rajamathi, M., Nataraja, G.D., Ananthamurthy, S., Kamath, P.V., Reversible thermal behavior of the layered double hydroxide of Mg with Al: Mechanistic studies (2000) J. Materials Chem., 10, pp. 2754-275
Formation Of A Novel Polypyrrole/porous Phosphate Glass Ceramic Nanocomposite
This work is concerned with evidences of a new composite system, formed by in situ polimerization of pyrrole moieties in the copper-exchanged pore surface of LiTi2(PO4)3 glass ceramic.102167168Ruiz-Hitzky, E., Aranda, P., (1997) An. Quim. Int. Ed., 93, p. 197Maia, D.J., Zarbin, A.J.G., Alves, O.L., De Paoli, M.-A., (1995) Adv. Mater., 7, p. 792Zarbin, A.J.G., De Paoli, M.-A., Alves, O.L., (1997) Synth. Met., 84, p. 107Zarbin, A.J.G., De Paoli, M.-A., Alves, O.L., (1999) Synth. Met., 99, p. 227Tarte, P., Rulmont, A., Merckaert-Ansay, C., (1986) Spectrochim. Acta, 42 A, p. 1009Hosono, H., Zhang, Z., Abe, Y., (1989) J. Am Ceram. Soc., 72, p. 1587Furukawa, Y., Tazawa, S., Fujii, Y., Harada, I., (1988) Synth. Met., 24, p. 32
Tin(iv) Phosphonates With α-layered Structure: Synthesis And Characterization
The synthesis of layered compounds of the general formula Sn(RPO 3)2·xH2O (R = phenyl, 2-carboxyethyl) and Sn(RPO3)2·xH2O (R = dodecyl) are reported. These compounds are formed by the reaction of nitric solutions of SnCl4 with the phosphonic acid or phosphoric ester followed by heating under reflux. The interlayer distances of 13.87, 15.37 and 32.70 Å for 2-carboxyethyl, phenyl and dodecyl derivatives, respectively, are determined by the XRD patterns. A linear relationship between the molar volume and the interlayer distance is observed suggesting an alpha structure similar to α-Sn(RPO4)2·H2O. FTIR spectra show the formation of an Sn- O-P skeleton.2101075107
Carbon Nanotubes Enhanced The Lead Toxicity On The Freshwater Fish
Carbon nanotubes are promising nanostructures for many applications in materials industry and biotechnology. However, it is mandatory to evaluate their toxicity and environmental implications. We evaluated nitric acid treated multiwalled carbon nanotubes (HNO3-MWCNT) toxicity in Nile tilapia (Oreochromis niloticus) and also the lead (Pb) toxicity modulation after the nanotube interaction. Industrial grade multiwalled carbon nanotubes [Ctube 100, CNT Co. Ltd] were treated with 9M HNO3 for 12h at 150°C to generate oxygenated groups on the nanotube surface, to improve water dispersion and heavy metal interaction. The HNO3-treated multiwalled carbon nanotubes were physico-chemically characterized by several techniques [e.g. TEM, FE-SEM, TGA, ζ-potential and Raman spectroscopy]. HNO3-MWCNT did not show toxicity on Nile tilapia when the concentration ranged from 0.1 to 3.0 mg/L, and the maximum exposure time was 96h. After 24, 48, 72 and 96h the LC50 values of Pb were 1.65, 1.32, 1.10 and 0.99 mg/L, respectively. To evaluate the Pb-nanotube interaction influence on the ecotoxicity, we submitted the Nile tilapia to different concentrations of Pb mixed with a non-toxic concentration of HNO3-MWCNT (1.0 mg/L). After 24, 48, 72, 96 h the LC50 values of Pb plus nanotubes were: 0.32, 0.25, 0.20, 0.18 mg/L, respectively. These values showed a synergistic effect after Pb-nanotube interaction since Pb toxicity increased over five times. X-ray energy dispersive spectroscopy (EDS) was used to confirm lead adsorption on the carbon nanotube oxidized surface. The exposure of Nile tilapia to Pb plus HNO3-MWCNT caused both oxygen consumption and ammonium excretion decrease, when compared to the control. Finally, our results show that carbon nanotubes interact with classical pollutants drawing attention to the environmental implications. © IOP Publishing Ltd 2013.4291Stéfani, D., Paula, A.J., Vaz, B.G., Silva, R.A., Andrade, N.F., Justo, G.Z., Ferreira, C.V., Alves, O.L., Structural and proactive safety aspects of oxidation debris from multiwalled carbon nanotubes (2011) J. Hazardous Materials, 189 (1-2), pp. 391-396. , 10.1016/j.jhazmat.2011.02.050 0304-3894Datsyuk, V., Kalyva, M., Papagelis, K., Parthenios, J., Tasis, D., Siokou, A., Kallitsis, I., Galiotis, C., Chemical oxidation of multiwalled carbon nanotubes (2008) Carbon, 46 (6), pp. 833-840. , 10.1016/j.carbon.2008.02.012 0008-6223Marques, R.R.N., MacHado, B.F., Faria, J.L., Silva, A.M.T., Controlled generation of oxygen functionalities on the surface of Single-Walled Carbon Nanotubes by HNO3 hydrothermal oxidation Carbon, 48 (5), pp. 1515-1523Wu, W.H., Chen, W., Lin, D.H., Yang, K., Influence of Surface Oxidation of Multiwalled Carbon Nanotubes on the Adsorption Affinity and Capacity of Polar and Nonpolar Organic Compounds in Aqueous Phase (2012) Environmental Sci. Technol., 46 (10), pp. 5446-5454. , 10.1021/es3004848 0013-936XDai, W., Liu, S.X., Fu, L.L., Du, H.H., Xu, Z.R., Lead (Pb) accumulation, oxidative stress and DNA damage induced by dietary Pb in tilapia (Oreochromis niloticus) (2012) Aquaculture Research, 43 (2), pp. 208-214. , 10.1111/j.1365-2109.2011.02817.x 1355-557XUmbuzeiro, G.A., Coluci, V.R., Honorio, J.G., Giro, R., Moraes, D.A., Lage, A.S.G., Mazzei, J.L., Alves, O.L., Understanding the interaction of multi-walled carbon nanotubes with mutagenic organic pollutants using computational modeling and biological experiments (2011) TRAC Trends Analytical Chem., 30 (3), pp. 437-446. , 10.1016/j.trac.2010.11.013 0165-9936Navarro, R.D., Navarro, F.K.S.P., Ribeiro, O.P., Ferreira, W.M., Pereira, M.M., Seixas, J.T., Quality of polyunsaturated fatty acids in Nile tilapias (Oreochromis niloticus) fed with vitamin e supplementation (2012) Food Chem., 134 (1), pp. 215-218. , 10.1016/j.foodchem.2012.02.097 0308-8146Kaya, H., Akbulut, M., Celik, E.S., Yilmaz, S., Aydin, F., Duysak, M., Effects of lead nitrate on haematological and immunological parameters in the tilapia (Oreochromis mossambicus, L. 1758) (2011) Toxicology Lett., 205, pp. 128-S132. , 10.1016/j.toxlet.2011.05.457 0378-4274Rashed, M.N., Cadmium and lead levels in fish (Tilapia nilotica) tissues as biological indicator for lake water pollution (2011) Environmental Monitoring Assessment, 68 (1), pp. 75-89. , 10.1023/A:1010739023662 0167-6369Wang, X., Acute toxicity and synergism of binary mixtures of antifouling biocides with heavy metals to embryos of sea urchin Glyptocidaris crenularis (2011) Human Experimental Toxicology, 30 (8), pp. 1009-1021. , 10.1177/0960327110385958 0960-3271Li, Y.H., Wang, S.G., Wei, J.Q., Zhang, X.F., Xu, C.L., Luan, Z.K., Wu, D.H., Wei, B.Q., Lead adsorption on carbon nanotubes (2002) Chem. Phys. Lett., 357 (3-4), pp. 263-266. , 10.1016/S0009-2614(02)00502-X 0009-2614Yu, X.Y., Luo, T., Zhang, Y.X., Jia, Y., Zhu, B.J., Fu, X.C., Liu, J.H., Huang, X.J., Adsorption of Lead(II) on O-2-Plasma-Oxidized Multiwalled Carbon Nanotubes: Thermodynamics, Kinetics, and Desorption (2011) ACS Appl. Materials Interfaces, 3 (7), pp. 2585-2593. , 10.1021/am2004202 1944-8244Barbieri, E., Paes, E.T., The use of oxygen consumption and ammonium excretion to evaluate the toxicity of cadmium on Farfantepenaeus paulensis with respect to salinity (2011) Chemosphere, 84 (1), pp. 9-16. , 10.1016/j.chemosphere.2011.02.092 0045-653
In Situ Synchrotron Radiation Small-angle X-ray Scattering Study Of The Kinetics Of Growth Of Cdte Nanocrystals In Borosilicate Glass
A number of isolator-semiconductor nanocrystal composites exhibit quantum confinement effects and nonlinear optical properties. In this work, the formation and growth of CdTe and CdTe0.9S0.1 nanocrystals immersed in a borosilicate glass host matrix were studied by small-angle x-ray scattering using synchrotron radiation during in situ annealing in the 560-580°C temperature range. The values of the average radii of the CdTe nanocrystals determined by using Guinier plots for different annealing times (20-30 Å) agree with those obtained from optical absorption spectroscopy measurements. The nanocrystal size distribution depends on the thermal history and composition of the samples. The existence of other structural heterogeneities having an average size of several hundred ångstroms was detected. © 1995 American Institute of Physics.6621338134
Thermal Decomposition Of [m3(co)12] (m = Ru, Os) Physisorbed Onto Porous Vycor Glass: A Route To A Glass/ruo2 Nanocomposite
This paper reports the preparation and characterization of oxide/glass nanocomposites, obtained by the impregnation and thermal decomposition of the trinuclear metal carbonyl clusters[M3(CO)12] (M = Ru, Os) inside the pores of porous Vycor glass (PVG). The intermediate species formed during the thermal treatment of the [M3(CO)12] adsorbed PVG materials were studied by UV-VIS-NIR and diffuse reflectance infrared (DR-IR) spectroscopy. At 65°C (M-Ru) and 110°C (M = Os), formation of surface bound [HM3(CO)10(μ- OSi≃)] species occurs, as a result of oxidative addition of a PVG surface silanol group to a cluster M-M bond. At T > 130°C (M = Ru) and T > 200°C (M = Os) cluster breakdown is observed, with formation of [M(CO)(n)(OSi≃)2] (n = 2 and/or 3) species. When [Ru3(CO)12] incorporated PVG is heated in air at T >250°C, decomposition of the cluster and formation of RuO2 nanoparticles are observed. 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Nanoparticles In Treatment Of Thermal Injured Rats: Is It Safe?
The aim of this study was to assess whether thermal trauma induced oxidative stress altered the balance between oxidant and antioxidant systems in the blood of burn wound rats in the absence and presence of silver nanoparticles and S-nitrosoglutathione, GSNO. Free silver nanoparticles, free GSNO and silver nanoparticles + GSNO had no cytotoxic effects. Under anesthesia, the shaved dorsum of the rats was exposed to 90°C (burn group) water bath. Studied compounds were administered topically immediately and at 28 days after the burn injury, four times a day. Silver nanoparticles and silver nanoparticles + GSNO were no toxic in vitro and in vivo. There were no significant differences in the levels of urea, creatinine, aminotransferases and hematological parameters, in control-burn groups (free silver nanoparticles) and treated-burn groups (free GSNO or silver nanoparticles + GSNO). There were no differences in lipid peroxidation and in the levels of protein carbonyls and glutathione, used as oxidative stress markers. A little inflammatory cell response, papillary dermis vascularization, fibroblasts differentiated into contractile myofibroblasts and the presence of a large amount of extracellular matrix were evidenced in treated groups following skin injury. These results indicate that silver nanoparticles and GSNO may provide an effective action on wound healing.3041Tian, J., Wong, K.K.Y., Ho, C.M., Lok, C.N., Yu, W.Y., Che, C.M., Chiu, J.F., Tam, P.K.H., (2007) J. Chem. Med. Chem., 2, p. 129Teli, M.K., Mutalik, S., Rajanikant, G.K., (2010) Cur. Pharm. Design., 16, p. 1882Schaller, M., Laude, J., Bodewaldt, H., Hamm, G., Korting, H.C., (2004) Skin Pharmacol. Physiol., 17, p. 31Seabra, A.B., Da Silva, R., De Souza, G.F.P., De Oliveira, M.G., (2008) Artif. Organs, 32, p. 262Seabra, A.B., Pankotai, E., Fehér, M., Somlai, A., Kiss, L., Bíró, L., Szabó, C., Lacza, Z., (2007) Br. J. Dermatol., 156, p. 814Seabra, A.B., Martins, D., Simes, M.M.S.G., Da Silva, R., Brocchi, M., De Oliveira, M.G., (2010) Artif. Organs, 34, p. 204Durán, N., Marcato, P.D., Alves, O.L., De Souza, G.I.H., Esposito, E., (2005) J. Nanobiotechnol., 3, p. 1Durán, N., Marcato, P.D., De Souza, G.I.H., Alves, O.L., Esposito, E., (2007) J. Biomed. Nanotechnol., 3, p. 203Amadeu, T.P., Seabra, A.B., De Oliveira, M.G., Costa, A.M.A., (2007) J. Eur. Acad. Dermatol. Venereol., 21, p. 629Amadeu, T.P., Seabra, A.B., De Oliveira, M.G., Costa, A.M.A., (2008) J. Surg Res., 149, p. 84Correa, D.H.A., Melo, P.S., De Carvalho, C.A.A., De Azevedo, M.B.M., Durán, N., Haun, M., (2005) Eur. J. Pharmacol., 510, p. 17De Conti, R., Oliveira, D.A., Fernandes, A.M.A.P., Melo, P.S., Rodriguez, J.A., Haun, M., Castro, S.L., Durán, N., (1998) Vitro Mol. Toxicol, 11, p. 153Borefreund, E., Puerner, J.A., (1984) J. Tissue Cult. Methods, 9, p. 7Denizot, F., Lang, R., (1986) J. Immunol. Methods, 89, p. 271Michailidis, Y., Jamurta, A.Z., Nikolaidis, M.G., Fatouros, I.G., Koutedakis, Y., Papassotiriou, I., (2007) Med. Sci. Sport Exerc., 39, p. 1107Davis, T.A., Amare, M., Naik, S., Kovalchuk, A.L., Tadaki, D., (2007) Wound Repair Regen., 15, p. 57
Use Of Cscl To Enhance The Glass Stability Range Of Tellurite Glasses For Er3+ Doped Optical Fiber Drawing
Tellurite glasses are important as a host of Er3+ ions because of their great solubility and because they present broader gain bandwidths than Er3+-doped silica, with promise to increase the bandwidth of communication systems. However, the small glass stability range (GSR) of tellurite glasses compromises the quality of the optical fibers. We show that the addition of CsCl to tellurite glasses can increase their GSR, making it easier to draw good quality optical fibers. CsCl acts as a network modifier in glass systems, weakening the network by forming Te-Cl bonds. We show that the thermal expansion coefficient mismatch is in the right direction for optical fiber fabrication purposes and that the Bi2O3 content can be used to control the refractive index of clad and core glasses. Single-mode and multi-mode Er3+-doped optical fibers were produced by the rod-in-tube method using highly homogeneous TeO2-ZnO-Li 2O-Bi2O3-CsCl glasses. Far infrared spectra of the glass samples exhibit absorption bands of the Te-Cl bond.6469Mori, A., Ohishi, Y., Sudo, S., Erbium-doped tellurite glass fibre laser and amplifier (1997) Electron. Lett, 33 (10), pp. 863-864Sekiya, T., Mochida, N., Ohtsuka, A., Tonokawa, M., Raman-spectra of Mo-TeO2 (M = Mg, Sr, Ba and Zn) glasses (1994) J. Non-Cryst. Solids, 168, pp. 1-2,106-114Bindra, K.S., Bookey, H.T., Kar, A.K., Wherrette, B.S., Liu, X., Jha, A., Nonlinear optical properties of chalcogenide glasses: Observation of multiphoton absorption (2001) Appl. Phys. Lett, 79 (13), pp. 1939-1941Wang, J.S., Vogel, E.M., Snitzer, E., Jackel, J.L., da Silva, V.L., Silbergerg, Y., 1.3 μm emission of neodymium and praseodymium in tellurite-based glasses (1994) J. Non-Cryst. Solids, 178, pp. 109-113Shen, S., Jha, A., Zhang, E., Wilson, S.J., Compositional effects and spectroscopy of rare earths (Er3+, Tm3+, and Nd 3+) in tellurite glasses (2002) C.R. Chim, 5 (12), pp. 921-938Yamada, M., Mori, A., Ono, H., Kobayashi, K., Kanamori, T., Ohishi, Y., Broadband and gain-flattened Er3+-doped tellurite fibre amplifier constructed using a gain equaliser (1998) Electron. Lett, 34 (4), pp. 370-371Mori, K., Kobayashi, M., Yamada, T., Kanamori, K., Oikawa, Y., Nishida, Y., Ohishi, Y., Low noise broadband tellurite-based Er3+-doped fibre amplifiers (1998) Electron. Lett, 34 (9), pp. 887-888Snitzer, E., Vogel, E.M., Wang, J.S., Tellurite glass and fiber amplifier (1993), US Patent 5,251,062Aitken, B.G., Ellison, A.J.G., Tellurite glasses and optical components (2001), US Patent 6,194,334Ding, Y., Jiang, S., Hwang, B.C., Luo, T., Peyghambarian, N., Himei, Y., Ito, T., Miura, Y., Spectral properties of erbium-doped lead halotellurite glasses for 1.5 μm broadband amplification (2000) Opt. Mater, 15 (2), pp. 123-130Keiser, G., (1999) Optical Fiber Communication, , Mac-Graw Hill, New YorkBarbosa, L.C., Cesar, C.L., Mazali, I.O., Barbosa, L.C., Alves, O.L., Spectroscopic and thermal properties of Ga2S 3-Na2S-CsCl glasses (2006) J. Am. Ceram. Soc, 89 (3), pp. 1037-1041Mazali, I.O., Barbosa, L.C., Alves, O.L., Preparation and characterization of new niobophosphate glasses in the Li2O-Nb 2O5-CaO-P2O5 system (2004) J. Mater. Sci, 39 (6), pp. 1987-1995El-Kheshen, A.A., Zawrah, M.F., Sinterability, microstructure and properties of glass/ceramic composite (2003) Ceram. Int, 29 (3), pp. 251-257A. Hruby, Evaluation of glass-forming tendency by means of DTA, Czech. J. Phys. B, B22 1187-& (1972)Burger, H., Vogel, W., Kozhukharov, V., IR transmission and properties of glasses in the TeO2-[RNOM, RNXM, RN(SO4)M, RN(PO3)M and B2O3] systems (1985) Infr. Phys, 25 (1-2), pp. 395-409Higazy, A.A., Bridge, B., Infrared-Spectra of the vitreous system CO 3O4-P2O5 and their interpretation (1985) Jour. Mat. Sci, 20 (7), pp. 2345-2358Bridge, B., Round, R., Computation of the bulk modulus of the high temperature ceramic superconductor YBa2Cu3O7-X from unit-cell data (1988) Jour. Mat. Sci. Lett, 7 (1), pp. 63-65Reynoso, V.C.S., Barbosa, L.C., Alves, O.L., Aranha, N., César, C.L., Preparation and characterization of heavy-metal oxide glasses - Bi2O3-PbO-B2O3-GeO 2 system (1994) J. Mater. Chem, 4 (4), pp. 529-532Canale, J.E., Condrate, R.A., Nassau, K., Cornilsen, B.C., Characterization of various glasses in the binary PbO-GeO2 and Bi2O3-GeO2 systems (1986) J. Can. Ceram. Soc, 55, pp. 50-56Adams, D.M., Lloyd, M.H., Far-Infrared reflectance spectra of some hexachlorotellurates and other hexachlorometallates (1971) Jour. Chem. Soc. A.-Inorganic Phys Theor, 7, p. 878Gloge, D., Weakly guiding fibers (1971) Appl. Opt, , 10 [10] 2252-
Quantitative and geomorphologic parameterization of megaclasts within mass-transport complexes, offshore Taranaki Basin, New Zealand
Mass-transport complexes (MTCs) in sedimentary basins reflect the gravitational transport of sediments from the shelf edge to the abyssal plain. Megaclasts, large sedimentary blocks of hundreds of meters long within MTCs, can record kinematic and sedimentary information deemed essential to understanding source-to-sink systems. Yet, deformation structures in such megaclasts remain poorly understood. This study uses high-quality, three-dimensional (3-D) seismic reflection data from the deep-water Taranaki Basin offshore New Zealand to analyze the morphological character of 123 megaclasts and propose a new classification scheme based on their morphometric properties. The megaclasts are up to 400 m tall, 1900 m long, and 1200 m wide. In the study area, they are high- to moderate-amplitude features owing to their different lithologies and continuous-to-contorted seismic facies. The megaclasts can be classified as undeformed, rotated, deformed, and highly deformed based on their internal deformational styles. Two different kinds of morphological depressions observed on their basal shear zones further indicate whether the megaclasts are transported or formed in situ. Our study demonstrates that quantitative parameterization of the megaclasts provides important information about their deformational processes and a more complete understanding of megaclast emplacement along continental margins
THE EFFICIENCY OF SHOOT AND PLANTLET FORMATION OF Cephaelis ipecacuanha AFTER THREE SUBCULTURES IN VITRO
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