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Sample records for hydrothermally treated liquid

  1. Drying grain using a hydrothermally treated liquid lignite fuel

    SciTech Connect

    Bukurov, Z.; Cvijanovic, P.; Bukurov, M.; Ljubicic, B.R.

    1995-12-01

    A shortage of domestic oil and natural gas resources in Yugoslavia, particularly for agricultural and industrial purposes, has motivated the authors to explore the possibility of using liquid lignite as an alternate fuel for drying grain. This paper presents a technical and economic assessment of the possibility of retrofitting grain-drying plants currently fueled by oil or natural gas to liquid lignite fuel. All estimates are based on lignite taken from the Kovin deposit. Proposed technology includes underwater mining techniques, aqueous ash removal, hydrothermal processing, solids concentration, pipeline transport up to 120 km, and liquid lignite direct combustion. For the characterization of Kovin lignite, standard ASTM procedures were used: proximate, ultimate, ash, heating value, and Theological analyses were performed. Results from an extensive economic analysis indicate a delivered cost of US$20/ton for the liquid lignite. For the 70 of the grain-drying plants in the province of Vojvodina, this would mean a total yearly saving of about US $2,500,000. The advantages of this concept are obvious: easy to transport and store, nonflammable, nonexplosive, nontoxic, 30%-40% cheaper than imported oil and gas, domestic fuel is at hand. The authors believe that liquid lignite, rather than an alternative, is becoming more and more an imperative.

  2. Method for treating liquid wastes

    DOEpatents

    Katti, K.V.; Volkert, W.A.; Singh, P.; Ketring, A.R.

    1995-12-26

    The method of treating liquid waste in a media is accomplished by exposing the media to phosphinimines and sequestering {sup 99}Tc from the media by the phosphinimine (PN) functionalities. The system for treating the liquid waste in the media includes extraction of {sup 99}TcO{sub 4}{sup {minus}} from aqueous solutions into organic solvents or mixed organic/polar media, extraction of {sup 99}Tc from solutions on a solid matrix by using a container containing PN functionalities on solid matrices including an inlet and outlet for allowing flow of media through an immobilized phosphinimine ligand system contained within the container. Also, insoluble suspensions of phosphinimine functionalities on solid matrices in liquid solutions or present on supported liquid membranes (SLM) can be used to sequester {sup 99}Tc from those liquids. 6 figs.

  3. Method for treating liquid wastes

    DOEpatents

    Katti, Kattesh V.; Volkert, Wynn A.; Singh, Prahlad; Ketring, Alan R.

    1995-01-01

    The method of treating liquid waste in a media is accomplished by exposing the media to phosphinimines and sequestering .sup.99 Tc from the media by the phosphinimine (PN) functionalities. The system for treating the liquid waste in the media includes extraction of .sup.99 TcO.sub.4.sup.- from aqueous solutions into organic solvents or mixed organic/polar media, extraction of .sup.99 Tc from solutions on a solid matrix by using a container containing PN functionalities on solid matrices including an inlet and outlet for allowing flow of media through an immobilized phosphinimine ligand system contained within the container. Also, insoluble suspensions of phosphinimine functionalities on solid matrices in liquid solutions or present on supported liquid membranes (SLM) can be used to sequester .sup.99 Tc from those liquids.

  4. Instabilities during liquid migration into superheated hydrothermal systems

    SciTech Connect

    Fitzgerald, Shaun D.; Woods, Andrew W.

    1995-01-26

    Hydrothermal systems typically consist of hot permeable rock which contains either liquid or liquid and saturated steam within the voids. These systems vent fluids at the surface through hot springs, fumaroles, mud pools, steaming ground and geysers. They are simultaneously recharged as meteoric water percolates through the surrounding rock or through the active injection of water at various geothermal reservoirs. In a number of geothermal reservoirs from which significant amounts of hot fluid have been extracted and passed through turbines, superheated regions of vapor have developed. As liquid migrates through a superheated region of a hydrothermal system, some of the liquid vaporizes at a migrating liquid-vapor interface. Using simple physical arguments, and analogue laboratory experiments we show that, under the influence of gravity, the liquid-vapor interface may become unstable and break up into fingers.

  5. Physicochemical properties and digestibility of hydrothermally treated waxy rice starch.

    PubMed

    Zeng, Feng; Ma, Fei; Kong, Fansheng; Gao, Qunyu; Yu, Shujuan

    2015-04-01

    Waxy rice starch was subjected to annealing (ANN) and heat-moisture treatment (HMT). These starches were also treated by a combination of ANN and HMT. The impact of single and dual modifications (ANN-HMT and HMT-ANN) on the molecular weight (M(w)), crystalline structure, thermal properties, and the digestibility were investigated. The relative crystallinity and short-range order on the granule surface increased on ANN, whereas decreased on HMT. All treated starches showed lower M(w) than that of the native starch. Gelatinization onset temperature, peak temperature and conclusion temperature increased for both single and dual treatments. Increased slowly digestible starch content was found on HMT and ANN-HMT. However, resistant starch levels decreased in all treated starches as compared with native starch. The results would imply that hydrothermal treatment induced structural changes in waxy rice starch significantly affected its digestibility.

  6. Liquid CO2 venting on the seafloor: Yonaguni Knoll IV hydrothermal system, Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Konno, Uta; Tsunogai, Urumu; Nakagawa, Fumiko; Nakaseama, Miwako; Ishibashi, Jun-ichiro; Nunoura, Takuro; Nakamura, Ko-ichi

    2006-08-01

    We determined the chemical and isotopic compositions of the liquid CO2 found on Yonaguni IV knoll hydrothermal site, as well as those in hydrothermal fluid venting from the surrounding chimneys. The δ13C of both CO2 and CH4 in the liquid CO2 almost coincide with those in the hydrothermal fluid, suggesting that the liquid CO2 must be derived from the hydrothermal fluid. While showing homogeneous δ13C, the hydrothermal fluids exhibit wide variation in gas contents. Active phase separation must be taking place within the conduits. Besides, H2-depletion in the liquid CO2 suggests formation of solid CO2-hydrate must also precede the venting of liquid CO2. In conclusion, liquid CO2 must be produced through following subseafloor processes: phase separation of hydrothermal fluid due to boiling, formation of solid CO2-hydrate due to cooling of vapor phase, and melting of the solid CO2-hydrate to liquid CO2 due to a temperature increase within the sedimentary layer.

  7. Liquid CO2 venting on the seafloor: Yonaguni Knoll IV hydrothermal system, Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Konno, U.; Tsunogai, U.; Nakagawa, F.; Nakaseama, M.; Ishibashi, J.; Nunoura, T.; Nakamura, K.

    2006-12-01

    In 2000, an active hydrothermal site, venting high-temperature fluid up to 300 oC, was discovered by Shinkai 6500 on the top of Yonaguni Knoll IV during YK 00-06 cruise in Okinawa Trough. During the subsequent subseafloor survey using Shinkai 6500 in 2003 (YK03-05), vents of liquid CO2 droplets were found at the site. Similar liquid CO2 droplets had previously been found at the active hydrothermal sites at JADE hydrothermal field, Okinawa Trough, during the extensive seafloor survey using submersibles in 1989 [Sakai et al., 1990]. Besides, similar liquid CO2 venting has also been recognized in NW Eifuku hydrothermal site on Izu-Bonin- Mariana arc. It thus appears that liquid CO2 venting might be usual phenomenon in some submarine arc volcanoes. The detailed relation between seafloor venting liquid CO2 and the surrounding high-temperature hydrothermal fluid, however, was not clarified in their studies. Furthermore, no definite evidence was obtained for the presence of CO2-hydrate in the subsurface. In this study, in order to discuss the subseafloor processes responsible for producing liquid CO2 at the Yonaguni Knoll IV site, as well as the possibility of the occurrence of solid CO2-hydrate within the sediments, we determined the chemical and isotopic compositions of the liquid CO2 found on the site, as well as those in hydrothermal fluid venting from the surrounding chimneys. In consequence, the ^13C of both CO2 and CH4 in the liquid CO2 almost coincide with those in the hydrothermal fluid, suggesting that the liquid CO2 must be derived from the hydrothermal fluid. While showing homogeneous ^13C, the hydrothermal fluids exhibit wide variation in gas contents. Active phase separation must be taking place within the conduits. Besides, H2-depletion in the liquid CO2 suggests formation of solid CO2-hydrate must also precede the venting of liquid CO2. In conclusion, liquid CO2 must be produced through following subseafloor processes: phase separation of hydrothermal

  8. High-temperature synthesis of highly hydrothermal stable mesoporous silica and Fe-SiO{sub 2} using ionic liquid as a template

    SciTech Connect

    Liu, Hong; Wang, Mengyang; Hu, Hongjiu; Liang, Yuguang; Wang, Yong; Cao, Weiran; Wang, Xiaohong

    2011-03-15

    Mesoporous silicas and Fe-SiO{sub 2} with worm-like structures have been synthesized using a room temperature ionic liquid, 1-hexadecane-3-methylimidazolium bromide, as a template at a high aging temperature (150-190 {sup o}C) with the assistance of NaF. The hydrothermal stability of mesoporous silica was effectively improved by increasing the aging temperature and adding NaF to the synthesis gel. High hydrothermally stable mesoporous silica was obtained after being aged at 190 {sup o}C in the presence of NaF, which endured the hydrothermal treatment in boiling water at least for 10 d or steam treatment at 600 {sup o}C for 6 h. The ultra hydrothermal stability could be attributed to its high degree of polymerization of silicate. Furthermore, highly hydrothermal stable mesoporous Fe-SiO{sub 2} has been synthesized, which still remained its mesostructure after being hydrothermally treated at 100 {sup o}C for 12 d or steam-treated at 600 {sup o}C for 6 h. -- Graphical abstract: Worm-like mesoporous silica and Fe-SiO{sub 2} with high hydrothermal stability have been synthesized using ionic liquid 1-hexadecane-3-methylimidazolium bromide as a template under the assistance of NaF at high temperature. Display Omitted Research highlights: {yields} Increasing aging temperature improved the hydrothermal stability of materials. {yields}Addition of NaF enhanced the polymerization degree of silicates. {yields} Mesoporous SiO{sub 2} and Fe-SiO{sub 2} obtained have remarkable hydrothermal stability.

  9. Hydrothermally treated coals for pulverized coal injection. Technical progress report, April 1995--June 1995

    SciTech Connect

    Walsh, D.E.; Rao, P.D.; Ogunsola, O.; Lin, H.K.

    1995-07-01

    This project is investigating the suitability of hydrothermally dried low-rank coals for pulverized fuel injection into blast furnaces in order to reduce coke consumption. Coal samples from the Beluga coal field and Usibelli Coal Mine, Alaska, are being used for the study. Crushed coal samples were hydrothermally treated at three temperatures, 275, 300 and 325{degrees}C, for residence times ranging from 10 to 120 minutes. Products have been characterized to determine their suitability for pulverized coal injection. Characterization includes proximate and ultimate analyses, vitrinite reflectance, TGA reactivity and thermochemical modeling. A literature survey has been conducted.

  10. High-temperature synthesis of highly hydrothermal stable mesoporous silica and Fe-SiO 2 using ionic liquid as a template

    NASA Astrophysics Data System (ADS)

    Liu, Hong; Wang, Mengyang; Hu, Hongjiu; Liang, Yuguang; Wang, Yong; Cao, Weiran; Wang, Xiaohong

    2011-03-01

    Mesoporous silicas and Fe-SiO 2 with worm-like structures have been synthesized using a room temperature ionic liquid, 1-hexadecane-3-methylimidazolium bromide, as a template at a high aging temperature (150-190 °C) with the assistance of NaF. The hydrothermal stability of mesoporous silica was effectively improved by increasing the aging temperature and adding NaF to the synthesis gel. High hydrothermally stable mesoporous silica was obtained after being aged at 190 °C in the presence of NaF, which endured the hydrothermal treatment in boiling water at least for 10 d or steam treatment at 600 °C for 6 h. The ultra hydrothermal stability could be attributed to its high degree of polymerization of silicate. Furthermore, highly hydrothermal stable mesoporous Fe-SiO 2 has been synthesized, which still remained its mesostructure after being hydrothermally treated at 100 °C for 12 d or steam-treated at 600 °C for 6 h.

  11. The effect of chemically and hydrothermally treated rapeseed on the performance and thyroid parameters of layers.

    PubMed

    Jeroch, H; Brettschneider, J G; Dänicke, S; Jankowski, J; Kozłowski, K; Schöne, F

    2009-01-01

    A feeding trial with brown laying hens was carried out in order to examine the effects of chemical and hydrothermal treatment of rapeseeds on the performance and thyroid parameters of birds during a long-term experiment. Untreated and treated rapeseeds were included in layer diets at a level of 7.5, 15.0, 22.5 and 30.0%, and the results obtained were compared with a control group fed a diet containing no rapeseed. Rapeseed treatment involved a combination of chemical and hydrothermal processing with subsequent expansion and drying. This treatment decreased sinapine content, from 6152 mg rapeseed/kg to less than 50 mg/kg, and glucosinolate concentration, from 13.8 mmol per kg to 1.4 mmol per kg (basis - 91% dry matter). The inclusion of 22.5% and 30.0% of both untreated and treated rapeseeds significantly impaired egg-laying rate and feed conversion. Egg weight was significantly affected by rapeseed feeding, with a significant decline at the 30.0% vs. the 7.5% rapeseed level. Rapeseed inclusion in the diet had a negative influence on weight gain. An increase in the dietary levels of untreated rapeseeds caused a greater decrease in egg mass, hen weight and feed conversion ratio, compared with the respective levels of treated rapeseeds. Untreated rapeseeds at the lowest level of 7.5% in the diet caused an increase in thyroid weight, epithelial cell height and changes in other histomorphometric thyroid parameters, as well as a decrease in the serum concentrations of thyroid hormones. Treated rapeseeds at a dietary level of 22.5% evoked a dose response, which shows that the chemical and hydrothermal treatment of rapeseed considerably reduced the anti-thyroid effects.

  12. Hydrothermal waves in a liquid bridge with aspect ratio near the Rayleigh limit under microgravity

    NASA Astrophysics Data System (ADS)

    Schwabe, D.

    2005-11-01

    A 2 cSt silicone oil (Pr=28) liquid bridge of 15.0mm length 3.0mm radius A =L/r=5) was established under microgravity during the flight of the sounding rocket MAXUS-4. Four different temperature differences ΔT =7, 9, 10, and 12K were applied between the ends, each for sufficient time to reach steady-state thermocapillary flow conditions. The aim of the experiment—to observe the onset of hydrothermal waves and to measure their features such as the wave phase speed and the angle between the wave vector and the applied temperature gradient—was reached. We used microgravity in this experiment in a twofold manner: (1) a liquid bridge with A =5 can be established only under microgravity; (2) it was possible to study hydrothermal waves without the influence of gravity and without the aspect ratio restrictions at normal gravity.

  13. Adsorption of tungsten onto zeolite fly ash produced by hydrothermally treating fly ash in alkaline solution.

    PubMed

    Ogata, Fumihiko; Iwata, Yuka; Kawasaki, Naohito

    2014-01-01

    Fly ash (FA) was hydrothermally treated in an alkaline solution to produce zeolite fly ash (Z-FA). The properties of the FA and Z-FA were investigated. The amounts of tungsten (W) adsorbed onto the FA and Z-FA surfaces were evaluated. Z-FA was produced by hydrothermally treating FA in an alkaline solution. The specific surface area and pore volume of the Z-FA were greater than those of the FA. More W was adsorbed onto the Z-FA surface than onto the FA surface. The adsorption isotherms for W were fitted using both the Freundlich and Langmuir equations. The equilibrium concentrations of W adsorbed onto the FA and Z-FA surfaces were subsequently reached within 20 h. The pseudo-second-order model more accurately described the data than did the pseudo-first-order model. Sodium hydroxide solutions (1-50 mmol/L) were used to easily recover W from Z-FA, indicating that Z-FA was useful for recovering W from aqueous solutions.

  14. Fabrication of hollow mesoporous NiO hexagonal microspheres via hydrothermal process in ionic liquid

    SciTech Connect

    Zhao, Jinbo; Wu, Lili; Zou, Ke

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer Ni(OH){sub 2} precursors were synthesized in ionic liquid and water solution by hydrothermal method. Black-Right-Pointing-Pointer NiO hollow microspheres were prepared by thermal treatment of Ni(OH){sub 2} precursors. Black-Right-Pointing-Pointer NiO hollow microspheres were self-assembled by mesoporous cubic and hexagonal nanocrystals with high specific surface area. Black-Right-Pointing-Pointer The mesoporous structure is stable at 773 K. Black-Right-Pointing-Pointer The ionic liquid absorbed on the O-terminate surface of the crystals to form hydrogen bond and played key roles in determining the final shape of the NiO novel microstructure. -- Abstract: The novel NiO hexagonal hollow microspheres have been successfully prepared by annealing Ni(OH){sub 2}, which was synthesized via an ionic liquid-assisted hydrothermal method. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), N{sub 2} adsorption-desorption and Fourier transform infrared spectrometer (FTIR). The results show that the hollow NiO microstructures are self-organized by mesoporous cubic and hexagonal nanocrystals. The mesoporous structure possessed good thermal stability and high specific surface area (ca. 83 m{sup 2}/g). The ionic liquid 1-butyl-3methylimidazolium tetrafluoroborate ([Bmim][BF{sub 4}]) was found to play a key role in controlling the morphology of NiO microstructures during the hydrothermal process. The special hollow mesoporous architectures will have potential applications in many fields, such as catalysts, absorbents, sensors, drug-delivery carriers, acoustic insulators and supercapacitors.

  15. Conventional and microwave hydrothermal synthesis of monodispersed metal oxide nanoparticles at liquid-liquid interface

    EPA Science Inventory

    Monodispersed nanoparticles of metal oxide including ferrites MFe2O4 (M=, Ni, Co, Mn) and γ-Fe2O3, Ta2O5 etc. have been synthesized using a water-toluene interface under both conventional and microwave hydrothermal conditions. This general synthesis procedure uses readily availab...

  16. Liquid Carbon Dioxide Venting at the Champagne Hydrothermal Site, NW Eifuku Volcano, Mariana Arc

    NASA Astrophysics Data System (ADS)

    Lupton, J.; Lilley, M.; Butterfield, D.; Evans, L.; Embley, R.; Olson, E.; Proskurowski, G.; Resing, J.; Roe, K.; Greene, R.; Lebon, G.

    2004-12-01

    In March/April 2004, submersible dives with the remotely-operated vehicle ROPOS discovered an unusual CO2-rich hydrothermal system near the summit of NW Eifuku, a submarine volcano located at 21.49° N, 144.04° E in the northern Mariana Arc. Although several sites of hydrothermal discharge were located on NW Eifuku, the most intense venting was found at 1600-m depth at the Champagne site, slightly west of the volcano summit. The Champagne site was found to be discharging two distinct fluids into the ocean: a) several small white chimneys were emitting milky 103° C gas-rich hydrothermal fluid with at least millimolar levels of H2S and b) cold (< 4° C) droplets coated with a milky skin were rising slowly from the sediment. These droplets were later determined to consist mainly of liquid CO2, with H2S as a probable secondary component. The droplets were sticky, and did not tend to coalesce into larger droplets, even though they adhered to the ROV like clumps of grapes. The film coating the droplets was assumed to be CO2 hydrate (or clathrate) which is known to form whenever liquid CO2 contacts water under these P,T conditions. Samples of the 103° C hydrothermal fluids were collected in special gas-tight titanium sampling bottles that were able to withstand the high internal pressures created by the dissolved gases. The Champagne hydrothermal fluids contained a surprising 2.3 moles/kg of CO2, an order of magnitude higher than any CO2 values previously reported for submarine hydrothermal fluids. The overall gas composition was 87% CO2, < 0.1% CH4, < 2 ppm H2, 0.012 mM/kg 4He, with the remaining 13% (322 mM/kg) assumed to be sulfur gases (H2S, SO2, etc.). (Additional analyses planned will confirm the speciation of this sulfur gas component). The helium had R/RA = 7.3, typical of subduction zone systems (R = 3He/4He and RA = Rair). Isotopic analysis of the CO2 yielded δ 13C = -1.75 ‰ , much heavier than the -6.0 ‰ typical for carbon in MOR vent fluids. The C/3He

  17. Removal of Hexavalent Chromium from Electroplating Industrial Effluents by Using Hydrothermally Treated Fly Ash

    NASA Astrophysics Data System (ADS)

    Ram Mohan Rao, S.; Basava Rao, V. V.

    Chromium in the wastewater coming out from tanneries and electroplating industries is to be treated because of exposure to it may produce effects on the liver, kidney, gastrointestinal and immune systems. On the other hand, fly ash produced from coal fired power plants is having disposal problem and it has to be properly utilized. In this study, the fly ash, subjected to hydrothermal treatment is used as adsorbent to remove Cr (VI) from synthetic samples. The effect of initial stock solution, contact time, adsorbent dose and pH were studied in a batch experiment. Results are compared with powdered activated carbon, granular activated carbon and untreated fly ash. The capacity of adsorption was found to be increased in the case of treated fly ash and it follows the order of powdered activated carbon >granular activated carbon >treated fly ash >untreated fly ash. The adsorption isotherms of Langmuir constants and Freundlich constants for all the adsorbents were determined. The Langmuir adsorption isotherm was recommended.

  18. The effect of sulfur on vapor liquid fractionation of metals in hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Pokrovski, Gleb S.; Borisova, Anastassia Yu.; Harrichoury, Jean-Claude

    2008-02-01

    Despite the growing evidence that the vapor phase, formed through magma degassing and ore fluid boiling, can selectively concentrate and transport metals, the effects of major volatile components like sulfur, chlorine or carbon dioxide on the metal vapor-liquid fractionation and vapor-phase transport under magmatic-hydrothermal conditions remain poorly known. We performed systematic experiments to investigate the effect of sulfur ligands on metal vapor-liquid partitioning in model H 2O-S-NaCl-KCl-NaOH systems at temperatures from 350 to 500 °C. Results show that at acidic-to-neutral conditions, vapor-liquid equilibrium distribution coefficients, Km = mvapor / mliquid, where m is the mass concentration of the metal in corresponding phase, of metalloids (As, Sb) and base metals (Zn, Fe, Pb, Ag) are in the range 0.1-1.0 and 0.001-0.1, respectively, and are not significantly affected by the presence of geologically common sulfur concentrations, up to 1-3 wt.% S. In contrast, the partitioning of Cu, Au, and Pt into the vapor increases by a factor of 100 in comparison to the S-free water-salt system, yielding Km values of 0.5-1.0, 1-10, and 10-20, respectively, due to formation of volatile neutral complexes with H 2S and, possibly, SO 2. In neutral-to-basic systems, Zn, Pb, Fe and Ag show 10-100-fold increase of their partition coefficients, whereas Cu, Au and Pt exhibit Km values of up to several orders of magnitude lower, compared to acidic conditions at similar temperature, pressure and sulfur contents. These vapor-liquid distribution patterns result from combined effects of i) formation of volatile species with reduced sulfur ligands in the vapor phase, ii) changes in the metal speciation in the coexisting liquid phase as a function of pH, and iii) solute-solvent interactions in both phases. Our data explain the vapor-liquid fractionation trends for many metals as inferred in coexisting brine and vapor inclusions from magmatic-hydrothermal deposits, and provide a

  19. Ionic liquid assisted hydrothermal fabrication of hierarchically organized γ-AlOOH hollow sphere

    SciTech Connect

    Tang, Zhe; Liu, Yunqi; Li, Guangci; Hu, Xiaofu; Liu, Chenguang

    2012-11-15

    Highlights: ► The γ-AlOOH hollow spheres were synthesized via an ionic liquid-assisted hydrothermal treatment. ► Ionic liquid plays an important role in the morphology of the product. ► Ionic liquid can be easily removed from the product and reused in next experiment. ► A “aggregation–solution–recrystallization” formation mechanism may occur in the system. -- Abstract: Hierarchically organized γ-AlOOH hollow spheres with nanoflake-like porous surface texture have been successfully synthesized via an ionic liquid-assisted hydrothermal synthesis method in citric acid monohydrate (CAMs). It was found that ionic liquid [bmim]{sup +}Cl{sup −} played an important role in the morphology of the product due to its strong interactions with reaction particles. The samples were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM). The results show that the product has narrow particle size distribution (500–900 nm particle diameter range), high specific surface area (240.5 m{sup 2}/g) and large pore volume (0.61 cm{sup 3}/g). The corresponding γ-Al{sub 2}O{sub 3} hollow spheres can be obtained by calcining it at 550 °C for 3 h. The proposed formation mechanism and other influencing factors of the γ-AlOOH hollow sphere material, such as reaction temperature, reaction duration, CAMs and urea, have also been investigated.

  20. Surface stress anisotropy of treated glass and liquid crystal alignment

    NASA Astrophysics Data System (ADS)

    Mada, Hitoshi

    1981-07-01

    We measured the surface energy and its anisotropy both for a liquid crystal (7CB) and for some treated glasses which make the liquid crystal align. The treated glasses were prepared in the following five ways: (1) rubbing the glass surface with a cloth, (2) coating with PVA and rubbing, (3) coating with an inorganic surfactant of SiO and rubbing, (4) coating with carbon and rubbing, and (5) 60 ° oblique evaporation of SiO. The surface energy was obtained by measuring the contact angle of the liquids whose surface tensions are known. The interfacial energy and its anisotropy were calculated from the experimental results. The magnitude of the anisotropy of the interfacial energy is in good qualitative agreement with the orientational order parameter of the liquid crystal near the surface. Therefore, the alignment of the liquid crystal on the treated substrate is dependent on the anisotropy of the interfacial energy.

  1. Subcritical hydrothermal treatment for the recovery of liquid fertilizer from scallop entrails.

    PubMed

    Hwang, In-Hee; Aoyama, Hiroya; Abe, Natsuki; Matsuo, Takayuki; Matsuto, Toshihiko

    2015-01-01

    Scallop entrails are organic wastes containing abundant proteins and minerals but are considered difficult to recycle because of high cadmium concentrations. In this work, the current problem of scallop entrails recycling was investigated and a subcritical hydrothermal treatment (SCHT) was examined for the recovery of liquid fertilizer from scallop entrails. Scallop entrails are mainly recycled for composting and feedstuff production. However, the dilution by mixing scallop entrails with other feed waste was the sole countermeasure to reduce the cadmium concentration of compost. For feedstuff production, whole product derived from scallop entrails was exported to other countries instead of domestic utilization. Temperature, retention time (RT) at given temperature, and liquid-to-solid (LS) ratio were examined as SCHT conditions for scallop entrails processing. The extraction ratio of each constituent mainly depends on the temperature rather than the RT or the LS ratio. Upon the SCHT of scallop entrails at 200°C, an RT of 20 min, and an LS ratio of 10, the extraction of fertilizer constituents such as nitrogen, phosphorus, and potassium from the liquid product was optimum, whereas the release of cadmium was suppressed. The concentrations of heavy metals in the liquid product obtained using the above-mentioned SCHT conditions were below the maximum permissible concentration stipulated by the Fertilizer Control Law. SCHT is considered to be a feasible recycling method for scallop entrails to recover fertilizer components with a concomitant separation of cadmium from the product. PMID:25409578

  2. Subcritical hydrothermal treatment for the recovery of liquid fertilizer from scallop entrails.

    PubMed

    Hwang, In-Hee; Aoyama, Hiroya; Abe, Natsuki; Matsuo, Takayuki; Matsuto, Toshihiko

    2015-01-01

    Scallop entrails are organic wastes containing abundant proteins and minerals but are considered difficult to recycle because of high cadmium concentrations. In this work, the current problem of scallop entrails recycling was investigated and a subcritical hydrothermal treatment (SCHT) was examined for the recovery of liquid fertilizer from scallop entrails. Scallop entrails are mainly recycled for composting and feedstuff production. However, the dilution by mixing scallop entrails with other feed waste was the sole countermeasure to reduce the cadmium concentration of compost. For feedstuff production, whole product derived from scallop entrails was exported to other countries instead of domestic utilization. Temperature, retention time (RT) at given temperature, and liquid-to-solid (LS) ratio were examined as SCHT conditions for scallop entrails processing. The extraction ratio of each constituent mainly depends on the temperature rather than the RT or the LS ratio. Upon the SCHT of scallop entrails at 200°C, an RT of 20 min, and an LS ratio of 10, the extraction of fertilizer constituents such as nitrogen, phosphorus, and potassium from the liquid product was optimum, whereas the release of cadmium was suppressed. The concentrations of heavy metals in the liquid product obtained using the above-mentioned SCHT conditions were below the maximum permissible concentration stipulated by the Fertilizer Control Law. SCHT is considered to be a feasible recycling method for scallop entrails to recover fertilizer components with a concomitant separation of cadmium from the product.

  3. Ionic liquid-based hydrothermal synthesis of Lu2O3 and Lu2O3:Eu3+ microcrysals

    NASA Astrophysics Data System (ADS)

    Li, Yinyan; Xu, Shiqing

    2016-09-01

    Uniform and well-defined Lu2O3 and Lu2O3:Eu3+ microarchitectures have been successfully synthesized via a green and facile ionic liquid-based hydrothermal method followed by a subsequent calcination process. Novel 3D micro-rodbundles and 1D microrods of Lu2O3 and Lu2O3:Eu3+ were controllably obtained through this method. X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and photoluminescence spectra were used to characterize the micromaterials. The proposed formation mechanisms have been investigated on the basis of a series of SEM studies of the products obtained at different hydrothermal durations. The results indicated that hydrothermal temperature and the ionic liquid-tetrabutylammonium hydroxide were two key factors for the formation as well as the morphology control of the Lu2O3 and Lu2O3:Eu3+ microarchitectures.

  4. Ammonia stripping of biologically treated liquid manure.

    PubMed

    Alitalo, Anni; Kyrö, Aleksis; Aura, Erkki

    2012-01-01

    A prerequisite for efficient ammonia removal in air stripping is that the pH of the liquid to be stripped is sufficiently high. Swine manure pH is usually around 7. At pH 7 (at 20°C), only 0.4% of ammonium is in ammonia form, and it is necessary to raise the pH of swine slurry to achieve efficient ammonia removal. Because manure has a very high buffering capacity, large amounts of chemicals are needed to change the slurry pH. The present study showed that efficient air stripping of manure can be achieved with a small amount of chemicals and without strong bases like NaOH. Slurry was subjected to aerobic biological treatment to raise pH before stripping. This facilitated 8 to 32% ammonia removal without chemical treatment. The slurry was further subjected to repeated cycles of stripping with MgO and Ca(OH)(2) additions after the first and second strippings, respectively, to raise slurry pH in between the stripping cycles. After three consecutive stripping cycles, 59 to 86% of the original ammonium had been removed. It was shown that the reduction in buffer capacity of the slurry was due to ammonia and carbonate removal during the stripping cycles.

  5. Methods for sulfate removal in liquid-phase catalytic hydrothermal gasification of biomass

    DOEpatents

    Elliott, Douglas C; Oyler, James R

    2014-11-04

    Processing of wet biomass feedstock by liquid-phase catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a pre-treatment temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent removal of soluble sulfate contaminants, or combinations thereof. Processing further includes reacting the soluble sulfate contaminants with cations present in the feedstock material to yield a sulfate-containing precipitate and separating the inorganic precipitates and/or the sulfate-containing precipitates out of the wet feedstock. Having removed much of the inorganic wastes and the sulfate contaminants that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogeneous catalyst for gasification.

  6. Methods for sulfate removal in liquid-phase catalytic hydrothermal gasification of biomass

    DOEpatents

    Elliott, Douglas C; Oyler, James

    2013-12-17

    Processing of wet biomass feedstock by liquid-phase catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a pre-treatment temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent removal of soluble sulfate contaminants, or combinations thereof. Processing further includes reacting the soluble sulfate contaminants with cations present in the feedstock material to yield a sulfate-containing precipitate and separating the inorganic precipitates and/or the sulfate-containing precipitates out of the wet feedstock. Having removed much of the inorganic wastes and the sulfate contaminants that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogenous catalyst for gasification.

  7. Catalytic Hydrothermal Gasification

    SciTech Connect

    Elliott, Douglas C.

    2015-05-31

    The term “hydrothermal” used here refers to the processing of biomass in water slurries at elevated temperature and pressure to facilitate the chemical conversion of the organic structures in biomass into useful fuels. The process is meant to provide a means for treating wet biomass materials without drying and to access ionic reaction conditions by maintaining a liquid water processing medium. Typical hydrothermal processing conditions are 523-647K of temperature and operating pressures from 4-22 MPa of pressure. The temperature is sufficient to initiate pyrolytic mechanisms in the biopolymers while the pressure is sufficient to maintain a liquid water processing phase. Hydrothermal gasification is accomplished at the upper end of the process temperature range. It can be considered an extension of the hydrothermal liquefaction mechanisms that begin at the lowest hydrothermal conditions with subsequent decomposition of biopolymer fragments formed in liquefaction to smaller molecules and eventually to gas. Typically, hydrothermal gasification requires an active catalyst to accomplish reasonable rates of gas formation from biomass.

  8. Greater osteoblast and mesenchymal stem cell adhesion and proliferation on titanium with hydrothermally treated nanocrystalline hydroxyapatite/magnetically treated carbon nanotubes.

    PubMed

    Wang, Mian; Castro, Nathan J; Li, Jian; Keidar, Michael; Zhang, Lijie Grace

    2012-10-01

    With an increasingly active and aging population, a growing number of orthopedic procedures are performed annually. However, traditional orthopedic implants face many complications such as infection, implant loosening, and poor host tissue integration leading to implant failure. Metal implant materials such as titanium and its alloys are widely used in orthopedic applications mainly based on their excellent mechanical properties and biological inertness. Since human bone extracellular matrix is nanometer in dimension comprised of rich nanostructured hydroxyapatite particles and collagen nanofibers, it is highly desirable to design a biologically-inspired nanostructured coating which renders the biocompatible titanium surface into a biomimetic and bioactive interface, thus enhancing osteoblast adhesion and promoting osseointegration. For this purpose, a biomimetic nanostructured coating based on nanocrystalline hydroxyapatite and single wall carbon nanotubes was designed. Specifically, nano hydroxyapatites with good crystallinity and biomimetic dimensions were prepared via a wet chemistry method and hydrothermal treatment. Microcrystalline hydroxyapatite with larger grain sizes can be obtained without hydrothermal treatment. The carbon nanotubes with different diameter and length were synthesized via an arc plasma method in the presence or absence of a magnetic field. Transmission electron microscopy images illustrate the regular, rod-like nanocrystalline and biomimetic nanostructure of hydrothermally treated nano hydroxyapatite. In addition, the length of carbon nanotubes can be significantly increased under external magnetic fields when compared to nanotubes produced without a magnetic field. More importantly, the in vitro study demonstrated for the first time that osteoblast and mesenchymal stem cell adhesion and proliferation were greater on titanium with hydrothermally treated nanocrystalline hydroxyapatites/magnetically treated carbon nanotubes, which suggests

  9. Role of Graphene Oxide Liquid Crystals in Hydrothermal Reduction and Supercapacitor Performance.

    PubMed

    Wang, Bin; Liu, Jinzhang; Zhao, Yi; Li, Yan; Xian, Wei; Amjadipour, Mojtaba; MacLeod, Jennifer; Motta, Nunzio

    2016-08-31

    The formation of liquid crystal (LC) phases in graphene oxide (GO) aqueous solution is utilized to develop high-performance supercapacitors. To investigate the effect of LC formation on the properties of subsequently reduced GO (rGO), we compare films prepared through blade-coating of viscous LC-GO solution and ultrasonic spray-coating of diluted GO aqueous dispersion. After hydrothermal reduction under identical conditions, the films show different morphology, oxygen content, and specific capacitance. Trapped water in the LC GO film plays a role in preventing restacking of sheets and facilitating the removal of oxygenated groups during the reduction process. In device architectures with either liquid or polymer electrolyte, the specific capacitance of the blade-coated film is twice as high as that of the spray-coated one. For a blade-coated film with mass loading of 0.115 mg/cm(2), the specific capacitance reaches 286 F/g in aqueous electrolyte and 263 F/g in gelled electrolyte, respectively. This study suggests a route to pilot-scale production of high-performance graphene supercapacitors through blade-coated LC-GO films.

  10. Role of Graphene Oxide Liquid Crystals in Hydrothermal Reduction and Supercapacitor Performance.

    PubMed

    Wang, Bin; Liu, Jinzhang; Zhao, Yi; Li, Yan; Xian, Wei; Amjadipour, Mojtaba; MacLeod, Jennifer; Motta, Nunzio

    2016-08-31

    The formation of liquid crystal (LC) phases in graphene oxide (GO) aqueous solution is utilized to develop high-performance supercapacitors. To investigate the effect of LC formation on the properties of subsequently reduced GO (rGO), we compare films prepared through blade-coating of viscous LC-GO solution and ultrasonic spray-coating of diluted GO aqueous dispersion. After hydrothermal reduction under identical conditions, the films show different morphology, oxygen content, and specific capacitance. Trapped water in the LC GO film plays a role in preventing restacking of sheets and facilitating the removal of oxygenated groups during the reduction process. In device architectures with either liquid or polymer electrolyte, the specific capacitance of the blade-coated film is twice as high as that of the spray-coated one. For a blade-coated film with mass loading of 0.115 mg/cm(2), the specific capacitance reaches 286 F/g in aqueous electrolyte and 263 F/g in gelled electrolyte, respectively. This study suggests a route to pilot-scale production of high-performance graphene supercapacitors through blade-coated LC-GO films. PMID:27529434

  11. Mechanical and histological investigation of hydrothermally treated and untreated anodic titanium oxide films containing Ca and P.

    PubMed

    Ishizawa, H; Fujino, M; Ogino, M

    1995-11-01

    In a previous study a new method for forming thin hydroxyapatite (HA) layers on titanium was described. Titanium was anodized at 350 V in an electrolyte solution containing sodium beta-glycerophosphate and calcium acetate, and an anodic titanium oxide film containing Ca and P (AOFCP) was formed on the surface. Then numerous HA crystals were precipitated on the AOFCP during hydrothermal treatment in high-pressure steam at 300 degrees C. In this study three types of hydrothermally treated films differing in amounts of precipitated HA crystals and tensile adhesive strength, and untreated films were histologically and mechanically investigated in a transcortical rabbit femoral model for 8 weeks of implantation using light microscopy, scanning electron microscopy (SEM), and push-out tests. Machined titanium and HA ceramics served as control materials. The push-out shear strength and bone apposition of the AOFCP significantly increased after hydrothermal treatment, and were equivalent to those of HA ceramics, although the HA layer on the AOFCP was thin at 1-2 microns. From SEM observation of the pushed-out specimen, it was found that the thin HA layer had directly bonded to bone but the AOFCP had not. The push-out strength of the hydrothermally treated film resulted from the chemical bonding of the bone-HA layer interface, while that of the untreated film resulted from mechanical interlocking force between bone and the microprojections. There was a small difference in bone apposition but no significant difference in push-out strength with the amount of precipitated HA crystals on the treated films. Among the treated films, the film formed at the lowest electrolyte concentration showed the lowest bone apposition because of incomplete covering by the HA crystals, and showed the highest stability against mechanical failure because the adhesive strength was very high at about 38 mPa. Also, the hydrothermally untreated anodic oxide films, whose surfaces were rough as a result

  12. Soil-based treatment of partially treated liquid swine manure.

    PubMed

    Yang, H; Xiao, J; El-Din, M Gamal; Buchanan, I D; Bromley, D; Ikehata, K

    2007-01-01

    A soil-column system was tested for the removal of soluble organics and nutrients from partially treated liquid swine manure. The liquid manure was applied to the 900 mm deep (300 mm of local topsoil and 600 mm of local subsoil) soil columns continuously for an eight-week period, and leachate as well as soil samples were analysed. An effective liquid manure application rate of 17 mm d(-1) was determined based on a preliminary liquid manure soil-based treatment experiment. It was found that more than 90% of five-day biochemical oxygen demand, chemical oxygen demand, total Kjeldahl and ammonia nitrogen, and total phosphorus could be effectively removed from the liquid manure by the soil system. Nitrogen contents accumulated in the soil matrix mostly within the 0 to 300 mm depth, while no significant increase was observed in sub soils. Soil analyses indicated the occurrence of nitrification and denitrification in the soil columns. Nitrogen balance showed that about 42% of the applied nitrogen was lost from the system during the liquid manure soil-based treatment experiment, suggesting the emission of ammonia and other gaseous nitrogen generated through nitrification and denitrification. The leachate of the soil treatment system was used to irrigate Bermuda grass. No negative effect of leachate was observed on the plant growth.

  13. Hydrothermal microwave valorization of eucalyptus using acidic ionic liquid as catalyst toward a green biorefinery scenario.

    PubMed

    Xu, Ji-Kun; Chen, Jing-Huan; Sun, Run-Cang

    2015-10-01

    The application of the acidic ionic liquid (IL), 1-butyl-3-methylimidazolium hydrogensulfate ([bmim]HSO4), as a catalyst in the hydrothermal microwave treatment (HMT) and green upgradation of eucalyptus biomass has been investigated. The process was carried out in a microwave reactor system at different temperatures (140-200°C) and evaluated for severities. The xylooligosaccharides (XOS, refers to a DP of 2-6) yield up to 5.04% (w/w) of the initial biomass and 26.72% (w/w) of xylan were achieved. Higher temperature resulted in lower molecular weight product, and enhanced the concentration of monosaccharides and byproducts. The morphology and structure of the solid residues were performed using an array of techniques, such as SEM, XRD, FTIR, BET surface area, and CP/MAS (13)C NMR, by which the increase of crystallinity, the destruction of surface structure, and the changes in functional groups and compositions were studied after the pretreatment, thus significantly enhancing the enzymatic hydrolysis.

  14. Hydrothermal microwave valorization of eucalyptus using acidic ionic liquid as catalyst toward a green biorefinery scenario.

    PubMed

    Xu, Ji-Kun; Chen, Jing-Huan; Sun, Run-Cang

    2015-10-01

    The application of the acidic ionic liquid (IL), 1-butyl-3-methylimidazolium hydrogensulfate ([bmim]HSO4), as a catalyst in the hydrothermal microwave treatment (HMT) and green upgradation of eucalyptus biomass has been investigated. The process was carried out in a microwave reactor system at different temperatures (140-200°C) and evaluated for severities. The xylooligosaccharides (XOS, refers to a DP of 2-6) yield up to 5.04% (w/w) of the initial biomass and 26.72% (w/w) of xylan were achieved. Higher temperature resulted in lower molecular weight product, and enhanced the concentration of monosaccharides and byproducts. The morphology and structure of the solid residues were performed using an array of techniques, such as SEM, XRD, FTIR, BET surface area, and CP/MAS (13)C NMR, by which the increase of crystallinity, the destruction of surface structure, and the changes in functional groups and compositions were studied after the pretreatment, thus significantly enhancing the enzymatic hydrolysis. PMID:26119053

  15. Valorization of the aqueous phase obtained from hydrothermally treated Dunaliella salina remnant biomass.

    PubMed

    Pirwitz, Kristin; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2016-11-01

    Up to 90% of Dunaliella salina biomass remains unused after extraction of the main product β-carotene. The potential of mild hydrothermal liquefaction (HTL) to exploit this biomass as a source of valuable by-products was assessed. The results indicate that 80% of the remnant was converted into glucose by mild HTL (100°C, 0min). The recovered glucose was successfully used as a carbon source to cultivate biotechnologically relevant microorganisms, namely Chlorella vulgaris, Escherichia coli and Saccharomyces cerevisiae. Furthermore, the analysis of energy demand and operating costs confirms the beneficial effect of mild liquefaction on the overall process economics of algal β-carotene production. PMID:27475332

  16. Valorization of the aqueous phase obtained from hydrothermally treated Dunaliella salina remnant biomass.

    PubMed

    Pirwitz, Kristin; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2016-11-01

    Up to 90% of Dunaliella salina biomass remains unused after extraction of the main product β-carotene. The potential of mild hydrothermal liquefaction (HTL) to exploit this biomass as a source of valuable by-products was assessed. The results indicate that 80% of the remnant was converted into glucose by mild HTL (100°C, 0min). The recovered glucose was successfully used as a carbon source to cultivate biotechnologically relevant microorganisms, namely Chlorella vulgaris, Escherichia coli and Saccharomyces cerevisiae. Furthermore, the analysis of energy demand and operating costs confirms the beneficial effect of mild liquefaction on the overall process economics of algal β-carotene production.

  17. Vapor-Liquid Partitioning of Iron and Manganese in Hydrothermal Fluids: An Experimental Investigation with Application to the Integrated Study of Basalt-hosted Hydrothermal Systems

    NASA Astrophysics Data System (ADS)

    Pester, N. J.; Seyfried, W. E.

    2010-12-01

    The chemistry of deep-sea hydrothermal vent fluids, expressed at the seafloor, reflects a complex history of physicochemical reactions. After three decades of field and experimental investigations, the processes of fluid-mineral equilibria that transform seawater into that of a typical “black smoker” are generally well described in the literature. Deep crustal fluids, when encountering a given heat source that ultimately drives hydrothermal circulation, routinely intersect the two-phase boundary. This process results in the nearly ubiquitous observations of variable salinity in vent fluids and is often a secondary driver of circulation via the evolution of a more buoyant (i.e. less saline) phase. Phase separation in chemically complex fluids results in the partitioning of dissolved species between the two evolved phases that deviates from simple charge balance calculations and these effects become more prominent with increasing temperature and/or decreasing pressure along the two-phase envelope. This process of partitioning has not been extensively studied and the interplay between the effects of phase separation and fluid-mineral equilibrium are not well understood. Most basalt-hosted hydrothermal systems appear to enter a steady state mode wherein fluids approach the heat source at depth and rise immediately once the two-phase boundary is met. Thus, venting fluids exhibit only modest deviations from seawater bulk salinity and the effects of partitioning are likely minor for all but the most volatile elements. Time series observations at integrated study sites, however, demonstrate dynamic changes in fluid chemistry following eruptions/magmatic events, including order of magnitude increases in gas concentrations and unexpectedly high Fe/Cl ratios. In this case, the time dependence of vapor-liquid partitioning relative to fluid-mineral equilibrium must be considered when attempting to interpret changes in subsurface reaction conditions. The two-phase region of

  18. Methods for treating a liquid using draw solutions

    DOEpatents

    Wilson, Aaron D; Orme, Christopher J.

    2016-07-26

    Draw solutions comprising at least one N-cyclicalkyl-cycloalkylamine and a secondary solvent. The N-cyclicalkyl-cycloalkylamine comprises the chemical structure: ##STR00001## wherein n is 0, 1, or 2, n' is 0, 1, or 2, and each of R.sup.1-R.sup.6 is independently selected from the group consisting of an alkyl group, an alkoxy group, an acetyl group, an aryl group, a hydrogen group, a hydroxyl group, and a phosphorus-containing group. Methods of treating a liquid using the draw solution are also disclosed.

  19. The effect of NaOH concentration on the steam-hydrothermally treated bioactive microarc oxidation coatings containing Ca, P, Si and Na on pure Ti surface.

    PubMed

    Zhou, Rui; Wei, Daqing; Cao, Jianyun; Feng, Wei; Cheng, Su; Du, Qing; Li, Baoqiang; Wang, Yaming; Jia, Dechang; Zhou, Yu

    2015-04-01

    The microarc oxidation (MAO) coating covered pure Ti plates are steam-hydrothermally treated in autoclaves containing NaOH solutions with different concentrations of 0, 0.001, 0.01, 0.1 and 1mol·L(-1). Due to the composition of Ti, O, Ca, P, Si and Na elements in the MAO coating, anatase and hydroxyapatite (HA) crystals are generated from the previously amorphous MAO coating after the steam-hydrothermal treatment. Meanwhile, it is noticed that the amount of HA crystals increases but showing a decline trend in aspect ratio in morphologies with the increasing of NaOH concentration. Interestingly, the steam-hydrothermally treated MAO coatings exhibit better bonding strength with Ti substrate (up to 43.8±1.1MPa) than that of the untreated one (20.1±3.1MPa). In addition, benefiting from the corrosive attack of the dissolved NaOH in water vapor on the MAO coating, Ti-OH is also formed on the steam-hydrothermally treated MAO coating surface, which can trigger apatite nucleation. Thus, the steam-hydrothermally treated MAO coatings exhibit good apatite-inducing ability.

  20. The effect of NaOH concentration on the steam-hydrothermally treated bioactive microarc oxidation coatings containing Ca, P, Si and Na on pure Ti surface.

    PubMed

    Zhou, Rui; Wei, Daqing; Cao, Jianyun; Feng, Wei; Cheng, Su; Du, Qing; Li, Baoqiang; Wang, Yaming; Jia, Dechang; Zhou, Yu

    2015-04-01

    The microarc oxidation (MAO) coating covered pure Ti plates are steam-hydrothermally treated in autoclaves containing NaOH solutions with different concentrations of 0, 0.001, 0.01, 0.1 and 1mol·L(-1). Due to the composition of Ti, O, Ca, P, Si and Na elements in the MAO coating, anatase and hydroxyapatite (HA) crystals are generated from the previously amorphous MAO coating after the steam-hydrothermal treatment. Meanwhile, it is noticed that the amount of HA crystals increases but showing a decline trend in aspect ratio in morphologies with the increasing of NaOH concentration. Interestingly, the steam-hydrothermally treated MAO coatings exhibit better bonding strength with Ti substrate (up to 43.8±1.1MPa) than that of the untreated one (20.1±3.1MPa). In addition, benefiting from the corrosive attack of the dissolved NaOH in water vapor on the MAO coating, Ti-OH is also formed on the steam-hydrothermally treated MAO coating surface, which can trigger apatite nucleation. Thus, the steam-hydrothermally treated MAO coatings exhibit good apatite-inducing ability. PMID:25686996

  1. Isolation and Structural Characterization of Lignin from Cotton Stalk Treated in an Ammonia Hydrothermal System

    PubMed Central

    Kang, Sumin; Xiao, Lingping; Meng, Lingyan; Zhang, Xueming; Sun, Runcang

    2012-01-01

    To investigate the potential for the utilization of cotton stalk, ammonia hydrothermal treatment was applied to fractionate the samples into aqueous ammonia-soluble and ammonia-insoluble portions. The ammonia-soluble portion was purified to yield lignin fractions. The lignin fractions obtained were characterized by wet chemistry (carbohydrate analysis) and spectroscopy methods (FT-IR, 13C and 1H-13C HSQC NMR spectroscopy) as well as gel permeation chromatography (GPC). The results showed that the cotton stalk lignin fractions were almost absent of neutral sugars (0.43%–1.29%) and had relatively low average molecular weights (1255–1746 g/mol). The lignin fractions belonged to typical G-S lignin, which was composed predominately of G-type units (59%) and noticeable amounts of S-type units (40%) together with a small amount of H-type units (~1%). Furthermore, the ammonia-extractable lignin fractions were mainly composed of β-O-4′ inter-unit linkages (75.6%), and small quantities of β-β′ (12.2%), together with lower amounts of β-5′ carbon-carbon linkages (7.4%) and p-hydroxycinnamyl alcohol end groups. PMID:23203120

  2. Liquefaction and dechlorination of hydrothermally treated waste mixture containing plastics with glass powder.

    PubMed

    Sugano, Motoyuki; Shimizu, Takayuki; Komatsu, Akihiro; Kakuta, Yusuke; Hirano, Katsumi

    2011-03-15

    Additive effects of glass powder upon the product yields and chlorine distribution after liquefaction of hydrothermally pretreated mixed waste (HMW) are compared with liquefaction of HMW with any one of water, quartz sand, or glass powder plus water. As a result, addition of either water or quartz sand did not affect liquefaction and dechlorination of HMW. Further, water (5 g) addition did not enhance liquefaction and dechlorination of HMW with glass powder. On the other hand, after liquefaction of HMW with glass powder, the yields of chlorine in the gas and water insoluble constituents decreased and the chlorine yield in the water-soluble constituent increased significantly. Because sodium in glass powder dissolved in a small amount (0.5 g) of water resulted from dehydration of HMW during liquefaction. Further, hydrogen chloride derived from polyvinylchloride in HMW was neutralized by ion exchange between H(+) and Na(+) dissolved in a small amount of water forming NaCl in the Residue (water-soluble) constituent. Therefore, most of chlorine in HMW was removed easily by water extraction of the Residue constituent after liquefaction of HMW with glass powder. Further, upgrading of HMW into the oil constituent was enhanced due to inhibition of production of chlorine containing organic compounds. Accordingly, it was clarified that glass powder was the most effective additive for liquefaction and dechlorination of HMW.

  3. Mesoporous nanotube aggregates obtained from hydrothermally treating TiO 2 with NaOH

    NASA Astrophysics Data System (ADS)

    Tsai, Chien-Cheng; Nian, Jun-Nan; Teng, Hsisheng

    2006-12-01

    Nanotube aggregates with high porosity were prepared from hydrothermal treatment of TiO 2 particles in NaOH at 130 °C, followed by HCl rinsing to different pH values. Pore structure of the aggregates, which were mainly mesoporous, was characterized by analyzing the N 2 sorption isotherm with different methods including the t-plot and density function theory. The surface area, pore volume and mean pore size of the aggregates increased with the rinsing acidity to reach a maximum (e.g. 400 m 2/g in surface area) at pH 1.6 and then decreased with further increase of the acidity. The crystalline phase and composition of the aggregates were, as well, significantly affected by the acidity of the post-treatment rinsing. Large-surface area aggregates were of loosely-attached nanotubes, composed of both anatase TiO 2 and H 2Ti 2O 5·H 2O, obtained under a mildly acidic rinsing condition, while basic or highly acidic conditions resulted in the formation of closely coagulated dense structures consisting of different crystalline phases.

  4. Hydrothermal synthesis of copper selenides with controllable phases and morphologies from an ionic liquid precursor

    NASA Astrophysics Data System (ADS)

    Liu, Xiaodi; Duan, Xiaochuan; Peng, Peng; Zheng, Wenjun

    2011-12-01

    Cu2-xSe nanocrystals and CuSe nanoflakes are successfully synthesized through a convenient hydrothermal method from an ionic liquid precursor 1-n-butyl-3-ethylimidazolium methylselenite ([BMIm][SeO2(OCH3)]). The phases and morphologies of the copper selenides can be controlled by simply changing the atom ratio of Cu/Se in the reactants and reaction temperature. Furthermore, it is found that the [BMIm][SeO2(OCH3)] not only serves as Se source but also has influence on the shapes of CuSe nanoflakes. The adsorption of alkyl imidazolium rings ([BMIm]+) onto the (0001) facets of covellite CuSe prohibits the growth in the [0001] direction, and CuSe nuclei growth mainly processes along the six symmetric directions (+/-[01&cmb.macr;11], +/-[101&cmb.macr;1&cmb.macr;], and +/-[1&cmb.macr;100]) to form flakelike CuSe. The obtained copper selenides are characterized by XRD, SEM, EDS, XPS, TEM, and HRTEM. The results indicate that the Cu2-xSe nanocrystals are nearly spherical particles with an average diameter of about 20 nm, the hexagonal CuSe nanoflakes are single crystals with an edge length of 100-400 nm and a thickness of 25-50 nm. The potential formation mechanism of the copper selenides is also proposed.Cu2-xSe nanocrystals and CuSe nanoflakes are successfully synthesized through a convenient hydrothermal method from an ionic liquid precursor 1-n-butyl-3-ethylimidazolium methylselenite ([BMIm][SeO2(OCH3)]). The phases and morphologies of the copper selenides can be controlled by simply changing the atom ratio of Cu/Se in the reactants and reaction temperature. Furthermore, it is found that the [BMIm][SeO2(OCH3)] not only serves as Se source but also has influence on the shapes of CuSe nanoflakes. The adsorption of alkyl imidazolium rings ([BMIm]+) onto the (0001) facets of covellite CuSe prohibits the growth in the [0001] direction, and CuSe nuclei growth mainly processes along the six symmetric directions (+/-[01&cmb.macr;11], +/-[101&cmb.macr;1&cmb.macr;], and +/-[1

  5. Hydrothermal synthesis of superparamagnetic Fe{sub 3}O{sub 4} nanoparticles with ionic liquids as stabilizer

    SciTech Connect

    Liu, Xiao-Di Chen, Hao; Liu, Shan-Shan; Ye, Li-Qun; Li, Yin-Ping

    2015-02-15

    Highlights: • Superparamagnetic Fe{sub 3}O{sub 4} nanoparticles with good dispersity have been synthesized via hydrothermal method. • Ionic liquid [C{sub 16}mim]Cl acts as stabilizer for the Fe{sub 3}O{sub 4} nanoparticles. • Fe{sub 3}O{sub 4} nanoparticles have a saturation magnetization of 67.69 emu/g at 300 K. - Abstract: Superparamagnetic Fe{sub 3}O{sub 4} nanoparticles have been successfully synthesized under hydrothermal condition with the assistant of ionic liquid 1-hexadecyl-3-methylimidazolium chloride ([C{sub 16}mim]Cl). The structure and morphology of the sample have been investigated by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM), and the results indicate that the as-synthesized inverse spinel Fe{sub 3}O{sub 4} nanoparticles have an average diameter of about 10 nm and exhibit relatively good dispersity. More importantly, it is found that [C{sub 16}mim]Cl acts as stabilizer for the Fe{sub 3}O{sub 4} nanoparticles by adsorbing on the particles surfaces to prevent the agglomeration. In addition, the obtained superparamagnetic Fe{sub 3}O{sub 4} nanoparticles have a saturation magnetization of 67.69 emu/g at 300 K.

  6. Water, treated as the continuous liquid in and around cells.

    PubMed

    Van Oss, C J; Giese, R F; Docoslis, A

    2001-07-01

    In the quantitative treatment of non-covalent inter- and intra-cellular interactions taking place in water, in vitro as well as in vivo, it is essential to treat the surrounding and pervading liquid medium as the continuous medium. In the close vicinity of inter- and intra-cellular surfaces and of biopolymers the various different non-covalent forces may locally alter the structure of water in a number of ways, but these local structural changes can be quantitatively taken into account. The operative forces are: Lifshitz-van der Waals (LW) forces. Lewis acid-base (AB) forces and electrostatic (EL) forces. Of these, the AB forces are generally the preponderant ones, in aqueous media. This is due, inter alia, to the strong cohesive and adhesive hydrogen-bonding interactions typically occurring in and by water. Among the strong AB interactions occurring in water are hydrophobic attraction (the hydrophobic effect) and hydrophilic repulsion (hydration pressure). Also treated is the function of LW, AB and EL forces in: hydration; in the stability of particle and cell suspensions, the solubility of biopolymers, small organic solutes, and electrolytes; and in specific ligand-receptor (such as antigen-antibody) interactions.

  7. A consideration on relation between the oscillatory Marangoni flow in a liquid bridge and the hydrothermal wave in a thin liquid layer

    NASA Astrophysics Data System (ADS)

    Tagaya, Emi; Ueno, Ichiro; Kawamura, Hiroshi

    2003-11-01

    The hydrothermal wave (HW) in a thin liquid layer and the oscillatory flow field in a half-zone liquid bridge have been considered to take place through a similar instability mechanism, because the temperature waves propagate over the free surfaces in both cases. It has been, however, not well recognized that a definite difference exists in their propagation angles. The present study aims to grasp a relation between the HW in the thin liquid layer and the oscillatory Marangoni flow in a liquid bridge. A sharp temperature gradient owing to the existence of an isothermal rigid wall causes a rolling up of a cold fluid returning from the bottom surface. Then, the front of the HW is bent near the rigid hot wall. The traveling wave of the surface temperature over the oscillatory thermocapillary flow in the half-zone liquid bridge can be regarded as the bent part of the HW. Thus, the difference in the propagating angles of both geometries can be explained by considering the HW taking place in a finite region.

  8. A Novel Strategy for Preparation of Si-HA Coatings on C/C Composites by Chemical Liquid Vaporization Deposition/Hydrothermal Treatments

    PubMed Central

    Xin-bo, Xiong; Xin-ye, Ni; Ya-yun, Li; Cen-cen, Chu; Ji-zhao, Zou; Xie-rong, Zeng

    2016-01-01

    A novel strategy for the preparation of Si-doped hydroxyapatite (Si-HA) coatings on H2O2-treated carbon/carbon composites (C/C) was developed. HA coating was prepared on C/C through chemical liquid vaporization deposition (CLVD)/hydrothermal treatment. HA coating was immersed in an H2SiO3 solution at an autoclave at 413 K for transformation into Si-HA coating. The effects of H2SiO3 mass contents on the phase, morphology, and composition of the Si-HA coatings were studied through SEM, EDS,XRD, and FTIR. Their bonding performance to C/C was measured through a scratch test. Under the optimal content condition, the in vitro skull osteoblast response behaviors of the Si-HA coating were evaluated. Results showed that SiO32− could enter into the HA lattice and occupy the PO43− sites. Doped SiO32− significantly improved the bonding performance of the HA coating to C/C in comparison with the untreated HA. The adhesive strength of the coatings initially increased and then decreased with increasing H2SiO3 content. Meanwhile, the cohesive strength of the Si-HA coatings was almost nearly identical. The Si-HA coating achieved at a content of 90% H2SiO3 exhibited the best bonding performance, and its osteoblast compatibility in vitro was superior to that of the untreated HA coating on C/C through CLVD/hydrothermal treatment. PMID:27492664

  9. A Novel Strategy for Preparation of Si-HA Coatings on C/C Composites by Chemical Liquid Vaporization Deposition/Hydrothermal Treatments.

    PubMed

    Xin-Bo, Xiong; Xin-Ye, Ni; Ya-Yun, Li; Cen-Cen, Chu; Ji-Zhao, Zou; Xie-Rong, Zeng

    2016-08-05

    A novel strategy for the preparation of Si-doped hydroxyapatite (Si-HA) coatings on H2O2-treated carbon/carbon composites (C/C) was developed. HA coating was prepared on C/C through chemical liquid vaporization deposition (CLVD)/hydrothermal treatment. HA coating was immersed in an H2SiO3 solution at an autoclave at 413 K for transformation into Si-HA coating. The effects of H2SiO3 mass contents on the phase, morphology, and composition of the Si-HA coatings were studied through SEM, EDS,XRD, and FTIR. Their bonding performance to C/C was measured through a scratch test. Under the optimal content condition, the in vitro skull osteoblast response behaviors of the Si-HA coating were evaluated. Results showed that SiO3(2-) could enter into the HA lattice and occupy the PO4(3-) sites. Doped SiO3(2-) significantly improved the bonding performance of the HA coating to C/C in comparison with the untreated HA. The adhesive strength of the coatings initially increased and then decreased with increasing H2SiO3 content. Meanwhile, the cohesive strength of the Si-HA coatings was almost nearly identical. The Si-HA coating achieved at a content of 90% H2SiO3 exhibited the best bonding performance, and its osteoblast compatibility in vitro was superior to that of the untreated HA coating on C/C through CLVD/hydrothermal treatment.

  10. A Novel Strategy for Preparation of Si-HA Coatings on C/C Composites by Chemical Liquid Vaporization Deposition/Hydrothermal Treatments

    NASA Astrophysics Data System (ADS)

    Xin-Bo, Xiong; Xin-Ye, Ni; Ya-Yun, Li; Cen-Cen, Chu; Ji-Zhao, Zou; Xie-Rong, Zeng

    2016-08-01

    A novel strategy for the preparation of Si-doped hydroxyapatite (Si-HA) coatings on H2O2-treated carbon/carbon composites (C/C) was developed. HA coating was prepared on C/C through chemical liquid vaporization deposition (CLVD)/hydrothermal treatment. HA coating was immersed in an H2SiO3 solution at an autoclave at 413 K for transformation into Si-HA coating. The effects of H2SiO3 mass contents on the phase, morphology, and composition of the Si-HA coatings were studied through SEM, EDS,XRD, and FTIR. Their bonding performance to C/C was measured through a scratch test. Under the optimal content condition, the in vitro skull osteoblast response behaviors of the Si-HA coating were evaluated. Results showed that SiO32‑ could enter into the HA lattice and occupy the PO43‑ sites. Doped SiO32‑ significantly improved the bonding performance of the HA coating to C/C in comparison with the untreated HA. The adhesive strength of the coatings initially increased and then decreased with increasing H2SiO3 content. Meanwhile, the cohesive strength of the Si-HA coatings was almost nearly identical. The Si-HA coating achieved at a content of 90% H2SiO3 exhibited the best bonding performance, and its osteoblast compatibility in vitro was superior to that of the untreated HA coating on C/C through CLVD/hydrothermal treatment.

  11. A Novel Strategy for Preparation of Si-HA Coatings on C/C Composites by Chemical Liquid Vaporization Deposition/Hydrothermal Treatments.

    PubMed

    Xin-Bo, Xiong; Xin-Ye, Ni; Ya-Yun, Li; Cen-Cen, Chu; Ji-Zhao, Zou; Xie-Rong, Zeng

    2016-01-01

    A novel strategy for the preparation of Si-doped hydroxyapatite (Si-HA) coatings on H2O2-treated carbon/carbon composites (C/C) was developed. HA coating was prepared on C/C through chemical liquid vaporization deposition (CLVD)/hydrothermal treatment. HA coating was immersed in an H2SiO3 solution at an autoclave at 413 K for transformation into Si-HA coating. The effects of H2SiO3 mass contents on the phase, morphology, and composition of the Si-HA coatings were studied through SEM, EDS,XRD, and FTIR. Their bonding performance to C/C was measured through a scratch test. Under the optimal content condition, the in vitro skull osteoblast response behaviors of the Si-HA coating were evaluated. Results showed that SiO3(2-) could enter into the HA lattice and occupy the PO4(3-) sites. Doped SiO3(2-) significantly improved the bonding performance of the HA coating to C/C in comparison with the untreated HA. The adhesive strength of the coatings initially increased and then decreased with increasing H2SiO3 content. Meanwhile, the cohesive strength of the Si-HA coatings was almost nearly identical. The Si-HA coating achieved at a content of 90% H2SiO3 exhibited the best bonding performance, and its osteoblast compatibility in vitro was superior to that of the untreated HA coating on C/C through CLVD/hydrothermal treatment. PMID:27492664

  12. Fate of liquid CO2 discharged from the hydrothermal area in the Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Shitashima, K.; Maeda, Y.

    2005-12-01

    Deep-sea hydrothermal systems are suitable for the on-site field analysis of a high CO2 environment in the ocean. Hydrothermal fluids are highly enriched in CO2 and show lower pH (about pH2-3) relative to seawater. The observation of the hydrothermal CO2 would provide the opportunity for understanding the physic-chemical behavior and diffusion process of CO2 in the ocean. Furthermore, the information on the hydrothermal ecosystem in the high CO2 environment is important for an environment impact assessment of the CO2 ocean sequestration. The observation of behavior of natural CO2 droplets (8-10?, 0.5ml) was carried out in the deep-sea hydrothermal system at the Okinawa Trough. The natural CO2 droplet contains CO2 of 95-98%, H2S of 2-3% and other gas species. The rising CO2 droplets were tracked by an ROV, and depth, temperature, salinity, pH and pCO2 in seawater near the CO2 droplets were measured during their ascent by using CTD and in-situ pH/pCO2 sensor. The behavior of the rising CO2 droplets was observed with an HDTV camera on an ROV. Mapping survey (400m X 400m, 3 layers) of low pH distribution was performed on the natural CO2 venting area by the grid navigation of the ROV that installed a pH/pCO2 sensor. The droplet size and the rise rate of CO2 droplets decreased during their ascent in water column (from 1470m to 900m depth). The CO2 droplets dissolved gradually and became small CO2 clathrate while rising, and the rising clathrate materials were found to disappear at 918m depth (552m above the bottom). Although the pH just above the sea floor CO2 vents showed pH 5, the pH depression in seawater surrounding the rising CO2 droplets was not observed. The results of pH mapping survey showed only localized pH depression at the CO2 venting site.

  13. Adsorption of anionic MO or cationic MB from MO/MB mixture using polyacrylonitrile fiber hydrothermally treated with hyperbranched polyethylenimine.

    PubMed

    Fan, You; Liu, Hua-Ji; Zhang, Yao; Chen, Yu

    2015-01-01

    One-step hydrothermal treatment of polyacrylonitrile fiber (PANF) with hyperbranched polyethylenimine (HPEI) resulted in zwitterionic PANF-g-HPEI that contained not only the grafted HPEI moieties but also many COOH groups generated in situ. Increasing the weight gain of PANF-g-HPEI from 10% to 90% resulted in the increase of its COOH, amino and amide groups from 0.12 to 1.86 mmol/g, 1.44 to 8.90 mmol/g, and 0.67 to 2.12 mmol/g, respectively. Dye adsorption experiments demonstrated that (1) such PANF-g-HPEIs could effectively adsorb anionic Methyl Orange (MO) or cationic Methylene Blue (MB), through the pretreatment with acidic or basic solution, respectively; (2) PANF-g-HPEIs could selectively adsorb the anionic MO or the cationic MB from MO/MB mixture through the pretreatment with solution of pH=5 or 10, respectively; (3) the cationic or anionic dyes adsorbed by PANF-g-HPEIs could be reversibly desorbed by the aqueous solution of pH=1 or 10, respectively; (4) PANF-g-HPEI could be recycled efficiently, and its dye adsorption performances did not show pronounced loss even after 10 adsorption/desorption cycles, superior to PANF treated with the low molar-mass polyamines. PMID:25305362

  14. Study concerning the utilization of the ocean spreading center environment for the conversion of biomass to a liquid fuel. (Includes Appendix A: hydrothermal petroleum genesis). [Supercritical water

    SciTech Connect

    Steverson, M.; Stormberg, G.

    1985-01-01

    This document contains a report on the feasibility of utilizing energy obtained from ocean spreading centers as process heat for the conversion of municipal solid wastes to liquid fuels. The appendix contains a paper describing hydrothermal petroleum genesis. Both have been indexed separately for inclusion in the Energy Data Base. (DMC)

  15. Hydrothermally Treated Chitosan Hydrogel Loaded with Copper and Zinc Particles as a Potential Micronutrient-Based Antimicrobial Feed Additive

    PubMed Central

    Rajasekaran, Parthiban; Santra, Swadeshmukul

    2015-01-01

    Large-scale use of antibiotics in food animal farms as growth promoters is considered as one of the driving factors behind increasing incidence of microbial resistance. Several alternatives are under investigation to reduce the amount of total antibiotics used in order to avoid any potential transmission of drug resistant microbes to humans through food chain. Copper sulfate and zinc oxide salts are used as feed supplement as they exhibit antimicrobial properties in addition to being micronutrients. However, higher dosage of copper and zinc (often needed for growth promoting effect) to animals is not advisable because of potential environmental toxicity arising from excreta. Innovative strategies are needed to utilize the complete potential of trace minerals as growth promoting feed supplements. To this end, we describe here the development and preliminary characterization of hydrothermally treated chitosan as a delivery vehicle for copper and zinc nanoparticles that could act as a micronutrient-based antimicrobial feed supplement. Material characterization studies showed that hydrothermal treatment makes a chitosan hydrogel that rearranged to capture the copper and zinc metal particles. Systemic antimicrobial assays showed that this chitosan biopolymer matrix embedded with copper (57.6 μg/ml) and zinc (800 μg/ml) reduced the load of model gut bacteria (target organisms of growth promoting antibiotics), such as Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, and Lactobacillus fermentum under in vitro conditions. Particularly, the chitosan/copper/zinc hydrogel exhibited significantly higher antimicrobial effect against L. fermentum, one of the primary targets of antibiotic growth promoters. Additionally, the chitosan matrix ameliorated the cytotoxicity levels of metal supplements when screened against a murine macrophage cell line RAW 264.7 and in TE-71, a murine thymic epithelial cell line. In this proof-of-concept study, we show that by using

  16. Hydrothermally Treated Chitosan Hydrogel Loaded with Copper and Zinc Particles as a Potential Micronutrient-Based Antimicrobial Feed Additive.

    PubMed

    Rajasekaran, Parthiban; Santra, Swadeshmukul

    2015-01-01

    Large-scale use of antibiotics in food animal farms as growth promoters is considered as one of the driving factors behind increasing incidence of microbial resistance. Several alternatives are under investigation to reduce the amount of total antibiotics used in order to avoid any potential transmission of drug resistant microbes to humans through food chain. Copper sulfate and zinc oxide salts are used as feed supplement as they exhibit antimicrobial properties in addition to being micronutrients. However, higher dosage of copper and zinc (often needed for growth promoting effect) to animals is not advisable because of potential environmental toxicity arising from excreta. Innovative strategies are needed to utilize the complete potential of trace minerals as growth promoting feed supplements. To this end, we describe here the development and preliminary characterization of hydrothermally treated chitosan as a delivery vehicle for copper and zinc nanoparticles that could act as a micronutrient-based antimicrobial feed supplement. Material characterization studies showed that hydrothermal treatment makes a chitosan hydrogel that rearranged to capture the copper and zinc metal particles. Systemic antimicrobial assays showed that this chitosan biopolymer matrix embedded with copper (57.6 μg/ml) and zinc (800 μg/ml) reduced the load of model gut bacteria (target organisms of growth promoting antibiotics), such as Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, and Lactobacillus fermentum under in vitro conditions. Particularly, the chitosan/copper/zinc hydrogel exhibited significantly higher antimicrobial effect against L. fermentum, one of the primary targets of antibiotic growth promoters. Additionally, the chitosan matrix ameliorated the cytotoxicity levels of metal supplements when screened against a murine macrophage cell line RAW 264.7 and in TE-71, a murine thymic epithelial cell line. In this proof-of-concept study, we show that by using

  17. ZnFe2O4 nanoparticles: microwave-hydrothermal ionic liquid synthesis and photocatalytic property over phenol.

    PubMed

    Cao, Shao-Wen; Zhu, Ying-Jie; Cheng, Guo-Feng; Huang, Yue-Hong

    2009-11-15

    We report the microwave-hydrothermal ionic liquid (MHIL) synthesis and photocatalytic property over phenol of ZnFe(2)O(4) nanoparticles. Zn(CH(3)COO)(2).2H(2)O and Fe(NO(3))(3).9H(2)O were used as the zinc and iron sources, respectively, in the presence of CO(NH(2))(2) and the ionic liquid 1-n-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM][BF(4)]). Deionized water was used as a solvent. The ionic liquid [BMIM][BF(4)] and microwave heating temperature have significant influences on the crystal phase of the product. Different dosages of [BMIM][BF(4)] or microwave heating temperature could lead to the formation of different products such as ZnFe(2)O(4) and beta-FeOOH. The MHIL method has the advantages such as simplicity, rapidness and energy saving. The ZnFe(2)O(4) nanoparticles prepared by the MHIL method exhibit high photocatalytic activity for the degradation of phenol, which was up to 73% within 360 min. The TOC measurement confirmed the good photocatalytic efficiency of ZnFe(2)O(4) nanoparticles.

  18. Adsorption of 1-butyl-3-methylimidazolium chloride ionic liquid by functional carbon microspheres from hydrothermal carbonization of cellulose.

    PubMed

    Qi, Xinhua; Li, Luyang; Tan, Tengfei; Chen, Wenting; Smith, Richard L

    2013-03-19

    Functional carbonaceous material (FCM) loaded with carboxylic groups was prepared by hydrothermal carbonization of cellulose in the presence of acrylic acid. The resulting FCM was used as adsorbent for recovery of a water-soluble ionic liquid, 1-butyl-3-methyl-imidazolium chloride ([BMIM][Cl]). The FCM consisted of microspheres (100-150 nm) and had a low surface area (ca. 20 m(2)/g), but exhibited adsorption capacity comparable to that of commercial activated carbon which can be attributed to the presence of high content of polar oxygenated groups (-OH, -C═O, -COOH) as revealed by spectral analyses. Sorption of [BMIM][Cl] onto FCM adsorbent could be well-described by pseudo-second-order kinetics. Thermodynamic and adsorption isothermal analyses revealed that the adsorption process was spontaneous, exothermic, and could be described by the Freundlich adsorption model. The FCM adsorbent could be regenerated effectively and recycled for at least three times without loss of adsorption capacity. The results of this work provide a facile method for production of functional carbonaceous materials from renewable resources that can be used for treatment of aqueous streams containing small concentrations of ionic liquid, [BMIM][Cl]. PMID:23410095

  19. Adsorption of 1-butyl-3-methylimidazolium chloride ionic liquid by functional carbon microspheres from hydrothermal carbonization of cellulose.

    PubMed

    Qi, Xinhua; Li, Luyang; Tan, Tengfei; Chen, Wenting; Smith, Richard L

    2013-03-19

    Functional carbonaceous material (FCM) loaded with carboxylic groups was prepared by hydrothermal carbonization of cellulose in the presence of acrylic acid. The resulting FCM was used as adsorbent for recovery of a water-soluble ionic liquid, 1-butyl-3-methyl-imidazolium chloride ([BMIM][Cl]). The FCM consisted of microspheres (100-150 nm) and had a low surface area (ca. 20 m(2)/g), but exhibited adsorption capacity comparable to that of commercial activated carbon which can be attributed to the presence of high content of polar oxygenated groups (-OH, -C═O, -COOH) as revealed by spectral analyses. Sorption of [BMIM][Cl] onto FCM adsorbent could be well-described by pseudo-second-order kinetics. Thermodynamic and adsorption isothermal analyses revealed that the adsorption process was spontaneous, exothermic, and could be described by the Freundlich adsorption model. The FCM adsorbent could be regenerated effectively and recycled for at least three times without loss of adsorption capacity. The results of this work provide a facile method for production of functional carbonaceous materials from renewable resources that can be used for treatment of aqueous streams containing small concentrations of ionic liquid, [BMIM][Cl].

  20. Synthesis of flower-like Boehmite (γ-AlOOH) via a one-step ionic liquid-assisted hydrothermal route

    SciTech Connect

    Tang, Zhe Liang, Jilei Li, Xuehui Li, Jingfeng Guo, Hailing; Liu, Yunqi Liu, Chenguang

    2013-06-01

    A simple and novel synthesis process, one-step ionic liquid-assisted hydrothermal synthesis route, has been developed in the work to synthesize Bohemithe (γ-AlOOH) with flower-like structure. The samples were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscope (SEM). Ionic liquid [Omim]{sup +}Cl{sup −}, as a template, plays an important role in the morphology and pore structure of the products due to its strong interactions with reaction particles. With the increase in the dosage of ionic liquid [Omim]{sup +}Cl{sup −}, the morphology of the γ-AlOOH was changed from initial bundles of nanosheets (without ionic liquid) into final well-developed monodispersed 3D flower-like architectures ([Omim]{sup +}Cl{sup −}=72 mmol). The pore structure was also altered gradually from initial disordered slit-like pore into final relatively ordered ink-bottle pore. Furthermore, the proposed formation mechanism and other influencing factors such as reaction temperature and urea on formation and morphology of the γ-AlOOH have also been investigated. - Graphical abstract: The flower-like γ-AlOOH architectures composed by nanosheets with narrow size distribution (1.6–2.2 μm) and uniform pore size (6.92 nm) have been synthesized via a one-step ionic liquid-assisted hydrothermal route. - Highlights: • The γ-AlOOH microflowers were synthesized via an ionic liquid-assisted hydrothermal route. • Ionic liquid plays an important role on the morphology and porous structure of the products. • Ionic liquid can be easily removed from the products and reused in recycling experiments. • A “aggregation–recrystallization–Ostwald Ripening“formation mechanism may occur.

  1. Hydrothermal preparation of hybrid carbon/silica monolithic capillary column for liquid chromatography.

    PubMed

    Yang, Peiling; Wang, Wentao; Xiao, Xing; Jia, Li

    2014-08-01

    A simple, easy and economical approach for the preparation of a hybrid carbon/silica monolithic capillary column was described for the first time by using silica monolith as framework in combination with hydrothermal carbonization at 180°C. During the preparation process, formamide was introduced to the reaction solutions to reduce the dissolution rate of monolithic silica skeleton and its optimal concentration was 1.5 M. Fourier transform infrared spectrometry, scanning electron microscopy, energy dispersive X-ray spectrometry, and inverse size exclusion chromatography were carried out to characterize the as-prepared column. The results demonstrated that carbon spheres ranging from 150 to 1000 nm were successfully attached to the surface of silica skeleton. The prepared hybrid carbon/silica column had a permeability of 4.4 × 10(-14) m(2). Chromatographic performance of the column was evaluated by separation of various compounds including alkylbenzenes, nucleosides and bases, and aromatic acids. The column exhibited an efficiency of 75,000 plates/m for butylbenzene at the optimal linear velocity of 0.23 mm/s. The successful separation of these compounds and the study on mechanism indicated that the column can be applied in mixed-mode chromatography. PMID:24830747

  2. Development of Hydrothermal Liquefaction and Upgrading Technologies for Lipid-Extracted Algae Conversion to Liquid Fuels

    SciTech Connect

    Zhu, Yunhua; Albrecht, Karl O.; Elliott, Douglas C.; Hallen, Richard T.; Jones, Susanne B.

    2013-10-01

    Bench-scale tests were performed for lipid-extracted microalgae (LEA) conversion to liquid fuels via hydrotreating liquefaction (HTL) and upgrading processes. Process simulation and economic analysis for a large-scale LEA HTL and upgrading system were developed based on the best available test results. The system assumes an LEA feed rate of 608 dry metric ton/day and that the feedstock is converted to a crude HTL bio-oil and further upgraded via hydrotreating and hydrocracking to produce liquid hydrocarbon fuels, mainly alkanes. Performance and cost results demonstrate that HTL would be an effective option to convert LEA to liquid fuel. The liquid fuels annual yield was estimated to be 26.9 million gallon gasoline-equivalent and the overall energy efficiency at higher heating value basis was estimated to be 69.5%. The minimum fuel selling price (MFSP) was estimated to be $0.75/L with LEA feedstock price at $33.1 metric ton at dry basis and 10% internal rate of return. A sensitivity analysis indicated that the largest effects to production cost would come from the final products yields and the upgrading equipments cost. The impact of plant scale on MFSP was also investigated.

  3. Treating Total Liquid Refusal with Backward Chaining and Fading.

    ERIC Educational Resources Information Center

    Hagopian, Louis P.; And Others

    1996-01-01

    In this study of a 12-year-old boy with autism, mental retardation, and a history of severe gastrointestinal problems, who refused liquids and food, backward chaining was used to shape drinking from a cup and a fading procedure was used to increase the water he was required to drink. (Author/CR)

  4. Combined effect of carbon dioxide and sulfur on vapor-liquid partitioning of metals in hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Kokh, Maria A.; Lopez, Mathieu; Gisquet, Pascal; Lanzanova, Aurélie; Candaudap, Frédéric; Besson, Philippe; Pokrovski, Gleb S.

    2016-08-01

    Although CO2 is a ubiquitous volatile in geological fluids typically ranging from a few to more than 50 wt%, its effect on metal vapor-liquid fractionation during fluid boiling and immiscibility phenomena in the Earth's crust remains virtually unknown. Here we conducted first experiments to quantify the influence of CO2 on the partition of different metals in model water + salt + sulfur + CO2 systems at 350 °C and CO2 pressures up to 100 bar, which are typical conditions of formation of many hydrothermal ore deposits. In addition, we performed in situ Raman spectroscopy measurements on these two-phase systems, to determine sulfur and carbon speciation in the liquid and vapor phases. Results show that, in S-free systems and across a CO2 concentration range of 0-50 wt% in the vapor phase, the absolute vapor-liquid partitioning coefficients of metals (Kvap/liq = Cvap/Cliq, where C is the mass concentration of the metal in the corresponding vapor and liquid phase) are in the range 10-6-10-5 for Mo; 10-4-10-3 for Na, K, Cu, Fe, Zn, Au; 10-3-10-2 for Si; and 10-4-10-1 for Pt. With increasing CO2 from 0 to 50 wt%, Kvap/liq values decrease for Fe, Cu and Si by less than one order of magnitude, remain constant within errors (±0.2 log unit) for Na, K and Zn, and increase by 0.5 and 2 orders of magnitude, respectively for Au and Pt. The negative effect of CO2 on the partitioning of some metals is due to weakening of hydration of chloride complexes of some metals (Cu, Fe) in the vapor phase and/or salting-in effects in the liquid phase (Si), whereas both phenomena are negligible for complexes of other metals (Na, K, Zn, Mo). The only exception is Pt (and in a lesser extent Au), which partitions significantly more to the vapor of S-free systems in the presence of CO2, likely due to formation of volatile carbonyl (CO) complexes. In the S-bearing system, with H2S content of 0.1-1.0 wt% in the vapor, Kvap/liq values of Cu, Fe, Mo, and Au are in the range 0.01-0.1, those of Pt 0

  5. Microalgal Cultivation in Treating Liquid Digestate from Biogas Systems.

    PubMed

    Xia, Ao; Murphy, Jerry D

    2016-04-01

    Biogas production via anaerobic digestion (AD) has rapidly developed in recent years. In addition to biogas, digestate is an important byproduct. Liquid digestate is the major fraction of digestate and may contain high levels of ammonia nitrogen. Traditional processing technologies (such as land application) require significant energy inputs and raise environmental risks (such as eutrophication). Alternatively, microalgae can efficiently remove the nutrients from digestate while producing high-value biomass that can be used for the production of biochemicals and biofuels. Both inorganic and organic carbon sources derived from biogas production can significantly improve microalgal production. Land requirement for microalgal cultivation is estimated as 3% of traditional direct land application of digestate. PMID:26776247

  6. Techno-Economic Analysis of Liquid Fuel Production from Woody Biomass via Hydrothermal Liquefaction (HTL) and Upgrading

    SciTech Connect

    Zhu, Yunhua; Biddy, Mary J.; Jones, Susanne B.; Elliott, Douglas C.; Schmidt, Andrew J.

    2014-09-15

    A series of experimental work was conducted to convert woody biomass to gasoline and diesel range products via hydrothermal liquefaction (HTL) and catalytic hydroprocessing. Based on the best available test data, a techno-economic analysis (TEA) was developed for a large scale woody biomass based HTL and upgrading system to evaluate the feasibility of this technology. In this system, 2000 dry metric ton per day woody biomass was assumed to be converted to bio-oil in hot compressed water and the bio-oil was hydrotreated and/or hydrocracked to produce gasoline and diesel range liquid fuel. Two cases were evaluated: a stage-of-technology (SOT) case based on the tests results, and a goal case considering potential improvements based on the SOT case. Process simulation models were developed and cost analysis was implemented based on the performance results. The major performance results included final products and co-products yields, raw materials consumption, carbon efficiency, and energy efficiency. The overall efficiency (higher heating value basis) was 52% for the SOT case and 66% for the goal case. The production cost, with a 10% internal rate of return and 2007 constant dollars, was estimated to be $1.29 /L for the SOT case and $0.74 /L for the goal case. The cost impacts of major improvements for moving from the SOT to the goal case were evaluated and the assumption of reducing the organics loss to the water phase lead to the biggest reduction in the production cost. Sensitivity analysis indicated that the final products yields had the largest impact on the production cost compared to other parameters. Plant size analysis demonstrated that the process was economically attractive if the woody biomass feed rate was over 1,500 dry tonne/day, the production cost was competitive with the then current petroleum-based gasoline price.

  7. Corrosion behavior of surface treated steel in liquid sodium negative electrode of liquid metal battery

    NASA Astrophysics Data System (ADS)

    Lee, Jeonghyeon; Shin, Sang Hun; Lee, Jung Ki; Choi, Sungyeol; Kim, Ji Hyun

    2016-03-01

    While liquid metal batteries are attractive options for grid-scale energy storage applications as they have flexible siting capacities and small footprints, the compatibility between structural materials such as current collectors and negative electrode such as sodium is one of major issues for liquid metal batteries. Non-metallic elements such as carbon, oxygen, and nitrogen in the liquid sodium influence the material behaviors of the cell construction materials in the battery system. In this study, the compatibility of structural materials with sodium is investigated in high temperature liquid sodium, and electrochemical impedance spectroscopy (EIS) is used to monitor in-situ the corrosion behavior at the surface of materials in sodium. Chemical vapor deposition (CVD) coatings of SiC and Si3N4 are applied as protective barriers against dissolution and corrosion on the steel surface. The results show that CVD coating of Si compounds can delay corrosion of steel in high temperature liquid sodium comparing to the result of as-received specimens, while SiC coating is more durable than Si3N4 coating in high temperature liquid sodium.

  8. Microscopic characterization of tension wood cell walls of Japanese beech (Fagus crenata) treated with ionic liquids.

    PubMed

    Kanbayashi, Toru; Miyafuji, Hisashi

    2016-09-01

    Tension wood that is an abnormal part formed in angiosperms has been barely used for wood industry. In this study, to utilize the tension wood effectively by means of liquefaction using ionic liquid, we performed morphological and topochemical determination of the changes in tension wood of Japanese beech (Fagus crenata) during ionic liquid treatment at the cellular level using light microscopy, scanning electron microscopy and confocal Raman microscopy. Ionic liquid treatment induced cell wall swelling in tension wood. Changes in the tissue morphology treated with ionic liquids were different between normal wood and tension wood, moreover the types of ionic liquids. The ionic liquid 1-ethyl-3-methylimidazolium chloride liquefied gelatinous layers rapidly, whereas 1-ethylpyridinium bromide liquefied slowly but delignified selectively. These novel insights into the deconstruction behavior of tension wood cell walls during ionic liquid treatment provide better understanding of the liquefaction mechanism. The obtained knowledge will contribute to development of an effective chemical processing of tension wood using ionic liquids and lead to efficient use of wood resources. PMID:27285953

  9. Microscopic characterization of tension wood cell walls of Japanese beech (Fagus crenata) treated with ionic liquids.

    PubMed

    Kanbayashi, Toru; Miyafuji, Hisashi

    2016-09-01

    Tension wood that is an abnormal part formed in angiosperms has been barely used for wood industry. In this study, to utilize the tension wood effectively by means of liquefaction using ionic liquid, we performed morphological and topochemical determination of the changes in tension wood of Japanese beech (Fagus crenata) during ionic liquid treatment at the cellular level using light microscopy, scanning electron microscopy and confocal Raman microscopy. Ionic liquid treatment induced cell wall swelling in tension wood. Changes in the tissue morphology treated with ionic liquids were different between normal wood and tension wood, moreover the types of ionic liquids. The ionic liquid 1-ethyl-3-methylimidazolium chloride liquefied gelatinous layers rapidly, whereas 1-ethylpyridinium bromide liquefied slowly but delignified selectively. These novel insights into the deconstruction behavior of tension wood cell walls during ionic liquid treatment provide better understanding of the liquefaction mechanism. The obtained knowledge will contribute to development of an effective chemical processing of tension wood using ionic liquids and lead to efficient use of wood resources.

  10. Hydrothermal Processing

    SciTech Connect

    Elliott, Douglas C.

    2011-03-11

    This chapter is a contribution to a book on Thermochemical Conversion of Biomass being edited by Prof. Robert Brown of Iowa State University. It describes both hydrothermal liquefaction and hydrothermal gasification of biomass to fuels.

  11. 75 FR 1704 - Modification to Consolidated Return Regulation Permitting an Election To Treat a Liquidation of a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ... Permitting an Election To Treat a Liquidation of a Target, Followed by a Recontribution to a New Target, as a... amendment. Summary: This document contains a correction to temporary regulations (TD 9458), which were... return regulation permitting an election to treat a liquidation of a target, followed by a...

  12. Template-free synthesis of CdS hollow nanospheres based on an ionic liquid assisted hydrothermal process and their application in photocatalysis

    SciTech Connect

    Li Xinping; Gao Yanan; Yu Li; Zheng Liqiang

    2010-06-15

    Polycrystalline CdS hollow nanospheres with diameter of about 130 nm have been successfully synthesized in high yield by an ionic liquid (IL) assisted template-free hydrothermal method for the first time. Both the molar ratios of Cd/S precursor in the solution and the reaction temperature play important roles in the formation of the CdS hollow nanospheres. The concentrations of capping agent hexamethylenetetramine (HMT) and polyvinylpyrrolidone (PVP) are also crucial for the morphology and size of the final product. IL was found to be a key component in the formation of CdS hollow structures, because solid spheres were obtained in the absence of IL. A subsequent growth mechanism of hollow interior by localized Ostwald ripening process has been further discussed. Such hollow structures show high photocatalytic ability in the photodegradation of methylene blue. - Graphical abstract: TEM images of typical as-prepared CdS hollow nanospheres.

  13. Prevention of trace and major element leaching from coal combustion products by hydrothermally-treated coal ash

    SciTech Connect

    Adnadjevic, B.; Popovic, A.; Mikasinovic, B.

    2009-07-01

    The most important structural components of coal ash obtained by coal combustion in 'Nikola Tesla A' power plant located near Belgrade (Serbia) are amorphous alumosilicate, alpha-quartz, and mullite. The phase composition of coal ash can be altered to obtain zeolite type NaA that crystallizes in a narrow crystallization field (SiO{sub 2}/Al{sub 2}O{sub 3}; Na{sub 2}O/SiO{sub 2}; H{sub 2}O/Na{sub 2}O ratios). Basic properties (crystallization degree, chemical composition, the energy of activation) of obtained zeolites were established. Coal ash extracts treated with obtained ion-exchange material showed that zeolites obtained from coal ash were able to reduce the amounts of iron, chromium, nickel, zinc, copper, lead, and manganese in ash extracts, thus proving its potential in preventing pollution from dump effluent waters.

  14. In situ observations of liquid-liquid phase separation in aqueous ZnSO4 solutions at temperatures up to 400 °C: Implications for Zn2+-SO42- association and evolution of submarine hydrothermal fluids

    NASA Astrophysics Data System (ADS)

    Wang, Xiaolin; Wan, Ye; Hu, Wenxuan; Chou, I.-Ming; Cao, Jian; Wang, Xiaoyu; Wang, Meng; Li, Zhen

    2016-05-01

    Liquid-liquid immiscibility is gaining recognition as an important process in hydrothermal fluid activity. However, studies of this complex process are relatively limited. We examined liquid-liquid immiscibility in aqueous ZnSO4 solutions at temperatures above ∼266.5 °C and at vapor-saturation pressures. The homogeneous aqueous ZnSO4 solution separated into ZnSO4-rich (L1) and ZnSO4-poor (L2) liquid phases coexisting with the vapor phase. The L1-L2 phase separation temperature decreased with increasing ZnSO4 concentration up to 1.0 mol/kg, and then increased at greater ZnSO4 concentrations, showing a typical lower critical solution temperature (LCST) of ∼266.5 °C. Gunningite (ZnSO4·H2O) precipitated in 2.0 mol/kg ZnSO4 solution at 360 °C. The L1-L2 phase separation resulted mainly from the strong Zn2+-SO42- association at high temperatures. The major results of this study are: (1) the discovery of the LCST in these systems, a macroscale property associated with polymeric mixtures; (2) analyses of the peak area ratios of the v1(SO42-) and OH stretching bands, which suggest that the sulfate concentration increases with increasing temperature in L1, especially above 375 °C; (3) a new Raman v1(SO42-) mode at ∼1005 cm-1 observed only in the L1 phase, whose fraction increases with increasing temperature; and (4) the shape of the OH Raman stretching band, which indicates that water molecules and solute interact much more strongly in L1 than in the coexisting L2 phase, suggesting that water molecules fit into the framework formed by various Zn2+-SO42- pairs and chain structures in L1. These results have potential implications for understanding transport and reduction of seawater-derived sulfate in submarine hydrothermal systems. The formation of an immiscible sulfate-rich liquid phase can favor the circulation of sulfate within mid-ocean ridge basalt because the sulfate-rich liquid density is higher than that of the coexisting fluid. The reduction of sulfate

  15. Ionic Liquid-Assisted Hydrothermal Method Synthesis of Flower-Like MoS2 and Their Electrochemical Performances.

    PubMed

    Li, Maohua; Yang, Bo; Hao, Junying; Lu, Yi; Long, Zerong; Liu, Yumei

    2016-06-01

    Molybdenum disulfide (MoS2) was prepared successfully via hydrothermal reaction at 200 degrees C in water/ethanol (1:1) solvent system using the ammonium molybdate and sodium thiosulfate as the molybdenum sources and sulfur sources, 1-butyl-3-methylimidazolium chloride salt [BMIM][Cl] as the additive agent. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the morphology and structure of flower-like products. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy spectrum analysis results show that the as-prepared product is a pure phase of MoS2. The prepared products are used as electrode materials for Li-ion batteries and showed excellent cycle stability and high Coulombic efficiency at a current density of 200 mA x g(-1) in the voltage range of 0.01 - 3.00 V (vs. Li/Li+). In addition, this paper also examined the influence of the reaction time and the amount of template agent on morphology, and discussed the reaction mechanism of the formation of flower-like morphology. PMID:27427696

  16. Ionic Liquid-Assisted Hydrothermal Method Synthesis of Flower-Like MoS2 and Their Electrochemical Performances.

    PubMed

    Li, Maohua; Yang, Bo; Hao, Junying; Lu, Yi; Long, Zerong; Liu, Yumei

    2016-06-01

    Molybdenum disulfide (MoS2) was prepared successfully via hydrothermal reaction at 200 degrees C in water/ethanol (1:1) solvent system using the ammonium molybdate and sodium thiosulfate as the molybdenum sources and sulfur sources, 1-butyl-3-methylimidazolium chloride salt [BMIM][Cl] as the additive agent. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the morphology and structure of flower-like products. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy spectrum analysis results show that the as-prepared product is a pure phase of MoS2. The prepared products are used as electrode materials for Li-ion batteries and showed excellent cycle stability and high Coulombic efficiency at a current density of 200 mA x g(-1) in the voltage range of 0.01 - 3.00 V (vs. Li/Li+). In addition, this paper also examined the influence of the reaction time and the amount of template agent on morphology, and discussed the reaction mechanism of the formation of flower-like morphology.

  17. Ultraviolet-light-treated polyimide alignment layers for polarization-independent liquid crystal Fresnel lenses

    NASA Astrophysics Data System (ADS)

    Hwang, S.-J.; Chen, T.-A.; Lin, K.-R.; Jeng, S.-C.

    2012-04-01

    The surface energy of a conventional homeotropic polyimide (PI) alignment layer was altered via ultraviolet (UV) light irradiation, and the pretilt angle of the PI was changed along with the surface energy. The surface energy can be controlled by either UV exposure time or irradiation intensity. A switchable liquid crystal Fresnel lens (LCFL) was created by the UV-treated alignment layers to form a Fresnel zone-distribution hybrid alignment, vertically aligned and hybrid aligned LC in the odd and even zones, respectively. The LCFL was made polarization-independent by circular buffing, and it had a diffraction efficiency of ˜22% at a low driving voltage of ˜1.2 V.

  18. Ionic liquid-assisted hydrothermal synthesis of dendrite-like NaY(MoO4)2:Tb3+ phosphor

    NASA Astrophysics Data System (ADS)

    Tian, Yue; Chen, Baojiu; Tian, Bining; Sun, Jiashi; Li, Xiangping; Zhang, Jinsu; Cheng, Lihong; Zhong, Haiyang; Zhong, Hua; Meng, Qingyu; Hua, Ruinian

    2012-07-01

    Micro-sized NaY(MoO4)2:Tb3+ phosphors with dendritic morphology was synthesized by a ionic liquid-assisted hydrothermal process. X-ray diffraction (XRD) indicated that the as-prepared product is pure tetragonal phase of NaY(MoO4)2. Field emission scanning electron microscopy (FE-SEM) images showed that the as-prepared NaY(MoO4)2:Tb3+ phosphors have dendritic morphology. The photoluminescent (PL) spectra displayed that the as-prepared NaY(MoO4)2:Tb3+ phosphors show a stronger green emission with main emission wavelength 545 nm corresponding to the 5D4→7F5 transition of Tb3+ ion, and the optimal Tb3+ doping concentration for obtaining maximum emission intensity was confirmed to be 10 mol%. Based on Van Uitert's and Dexter's models the electric dipole-dipole (D-D) interaction was confirmed to be responsible for the concentration quenching of 5D4 fluorescence of Tb3+ in the NaY(MoO4)2:Tb3+ phosphors. The intrinsic radiative transition lifetime of 5D4 level is found to be 0.703 ms.

  19. Highly sensitive and selective glucose sensor based on ultraviolet-treated nematic liquid crystals.

    PubMed

    Zhong, Shenghong; Jang, Chang-Hyun

    2014-09-15

    Glucose is an extremely important biomolecule, and the ability to sense it has played a significant role in facilitating the understanding of many biological processes. Here, we report a novel glucose sensor based on ultraviolet (UV)-treated nematic liquid crystals. Submerging UV-treated 4-cyano-4'-pentylbiphenyl (5CB) in a glucose solution (while carefully adjusting its pH to 7.5 with NaOH and HCl) triggered an optical response, from dark to bright, observed with a polarized microscope. Notably, 5CB was located inside a glucose oxidase (GOx)-modified gold grid. We exploited this pH-driven phenomenon to design a new glucose sensor. This device could detect as little as 1 pM analyte, which is 3 orders of magnitude lower than the detection limit of the most sensitive glucose sensor currently available. It also exhibits high selectivity due to GOx modification. Thus, this is a promising technique for glucose detection, not only for clinical diagnostics, but also for sensing low levels of glucose in a biological environment (e.g., single cells and bacterial cultures).

  20. Hydrothermal processes above the Yellowstone magma chamber: Large hydrothermal systems and large hydrothermal explosions

    USGS Publications Warehouse

    Morgan, L.A.; Shanks, W.C. Pat; Pierce, K.L.

    2009-01-01

    Hydrothermal explosions are violent and dramatic events resulting in the rapid ejection of boiling water, steam, mud, and rock fragments from source craters that range from a few meters up to more than 2 km in diameter; associated breccia can be emplaced as much as 3 to 4 km from the largest craters. Hydrothermal explosions occur where shallow interconnected reservoirs of steam- and liquid-saturated fluids with temperatures at or near the boiling curve underlie thermal fields. Sudden reduction in confi ning pressure causes fluids to fl ash to steam, resulting in signifi cant expansion, rock fragmentation, and debris ejection. In Yellowstone, hydrothermal explosions are a potentially signifi cant hazard for visitors and facilities and can damage or even destroy thermal features. The breccia deposits and associated craters formed from hydrothermal explosions are mapped as mostly Holocene (the Mary Bay deposit is older) units throughout Yellowstone National Park (YNP) and are spatially related to within the 0.64-Ma Yellowstone caldera and along the active Norris-Mammoth tectonic corridor. In Yellowstone, at least 20 large (>100 m in diameter) hydrothermal explosion craters have been identifi ed; the scale of the individual associated events dwarfs similar features in geothermal areas elsewhere in the world. Large hydrothermal explosions in Yellowstone have occurred over the past 16 ka averaging ??1 every 700 yr; similar events are likely in the future. Our studies of large hydrothermal explosion events indicate: (1) none are directly associated with eruptive volcanic or shallow intrusive events; (2) several historical explosions have been triggered by seismic events; (3) lithic clasts and comingled matrix material that form hydrothermal explosion deposits are extensively altered, indicating that explosions occur in areas subjected to intense hydrothermal processes; (4) many lithic clasts contained in explosion breccia deposits preserve evidence of repeated fracturing

  1. Hydrothermal Processes

    NASA Astrophysics Data System (ADS)

    German, C. R.; von Damm, K. L.

    2003-12-01

    What is Hydrothermal Circulation?Hydrothermal circulation occurs when seawater percolates downward through fractured ocean crust along the volcanic mid-ocean ridge (MOR) system. The seawater is first heated and then undergoes chemical modification through reaction with the host rock as it continues downward, reaching maximum temperatures that can exceed 400 °C. At these temperatures the fluids become extremely buoyant and rise rapidly back to the seafloor where they are expelled into the overlying water column. Seafloor hydrothermal circulation plays a significant role in the cycling of energy and mass between the solid earth and the oceans; the first identification of submarine hydrothermal venting and their accompanying chemosynthetically based communities in the late 1970s remains one of the most exciting discoveries in modern science. The existence of some form of hydrothermal circulation had been predicted almost as soon as the significance of ridges themselves was first recognized, with the emergence of plate tectonic theory. Magma wells up from the Earth's interior along "spreading centers" or "MORs" to produce fresh ocean crust at a rate of ˜20 km3 yr-1, forming new seafloor at a rate of ˜3.3 km2 yr-1 (Parsons, 1981; White et al., 1992). The young oceanic lithosphere formed in this way cools as it moves away from the ridge crest. Although much of this cooling occurs by upward conduction of heat through the lithosphere, early heat-flow studies quickly established that a significant proportion of the total heat flux must also occur via some additional convective process (Figure 1), i.e., through circulation of cold seawater within the upper ocean crust (Anderson and Silbeck, 1981). (2K)Figure 1. Oceanic heat flow versus age of ocean crust. Data from the Pacific, Atlantic, and Indian oceans, averaged over 2 Ma intervals (circles) depart from the theoretical cooling curve (solid line) indicating convective cooling of young ocean crust by circulating seawater

  2. 77 FR 36914 - Modification to Consolidated Return Regulation Permitting an Election To Treat a Liquidation of a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-20

    ... Regulation Permitting an Election To Treat a Liquidation of a Target, Followed by a Recontribution to a New Target, as a Cross-Chain Reorganization AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Final... a consolidated group can avoid immediately taking into account an intercompany item after...

  3. Adhesion strength measurements of excimer-laser-treated PTFE surfaces using liquid photoreagents

    NASA Astrophysics Data System (ADS)

    Hopp, Bela; Smausz, Tomi; Kresz, Norbert; Ignacz, Ferenc

    2003-04-01

    The most known feature of polytetrafluoroethylene (PTFE) is its adhesion behavior: it is hydrophobic and oleophobic at the same time. This can cause serious problems and obstacles during the surface treatment and fixing of PTFE objects. During our experiments Teflon films were irradiated by an ArF excimer laser beam in presence of liquid photoreagents containing amine groups (aminoethanol, 1,2-diaminoethane, triethylene-tetramine). In consequence of the treatment the adhesion of the modified surfaces significantly increased, the samples could be glued and moistened. The adhesion strength of the glued surfaces was measured in the function of the applied laser fluence. The adhesion strength increased drastically between 0 - 1 mJ/cm2 and showed saturation above 1 mJ/cm2 at approximately 5 - 9 MPa values depending on the applied photoreagents. On the basis of our experiments it was found that the treatment with triethylene-tetramine was the most effective. The surface chemical modifications of the treated Teflon samples can be due to the incorporation of amine groups into the surface layer.

  4. Converting ultrasonic induction heating deposited monetite coating to Na-doped HA coating on H 2O 2-treated C/C composites by a two-step hydrothermal method

    NASA Astrophysics Data System (ADS)

    Xin-bo, Xiong; Jian-feng, Hung; Xie-rong, Zeng; Cen-cen, Chu

    2011-10-01

    a monetite coating on H 2O 2-treated C/C composites was prepared by ultrasonic induction heating (UIH) technology. Subsequently, this coating was subjected to an ammonia hydrothermal treatment to form a undoped hydroxyapatite (U-HA) coating. Finally, the as-prepared U-HA coating was placed in a NaOH solution and hydrothermally treated to produce the other hydroxyapatite (Na-HA) coating. The structure, morphology and chemical composition of the two HA coatings were characterized by XRD, FTIR, SEM and EDS, the adhesiveness and local mechanical properties, e.g. nanohardness and Young's modulus of the two HA coatings to C/C composites was evaluated by a scratch test and nanoindentation technique respectively. The results showed that the two HA coatings had the alike morphology and crystallization. But, compared with the U-HA coating, the Na-HA coating was doped with Na ions, and gave a Ca/P ratio close to a stoichiometric hydroxyapatite, and thus showed a higher nano-indentation value, Young's modulus, and larger bonding strength. These results verified the strengthened effect of Na ion in hydroxyapatite coating on carbon/carbon (C/C) composities.

  5. Vapor-liquid partitioning of alkaline earth and transition metals in NaCl-dominated hydrothermal fluids: An experimental study from 360 to 465 °C, near-critical to halite saturated conditions

    NASA Astrophysics Data System (ADS)

    Pester, Nicholas J.; Ding, Kang; Seyfried, William E.

    2015-11-01

    Multi-phase fluid flow is a common occurrence in magmatic hydrothermal systems; and extensive modeling efforts using currently established P-V-T-x properties of the NaCl-H2O system are impending. We have therefore performed hydrothermal flow experiments (360-465 °C) to observe vapor-liquid partitioning of alkaline earth and first row transition metals in NaCl-dominated source solutions. The data allow extraction of partition coefficients related to the intrinsic changes in both chlorinity and density along the two-phase solvus. The coefficients yield an overall decrease in vapor affinity in the order Cu(I) > Na > Fe(II) > Zn > Ni(II) ⩾ Mg ⩾ Mn(II) > Co(II) > Ca > Sr > Ba, distinguished with 95% confidence for vapor densities greater than ∼0.2 g/cm3. The alkaline earth metals are limited to purely electrostatic interactions with Cl ligands, resulting in an excellent linear correlation (R2 > 0.99) between their partition coefficients and respective ionic radii. Though broadly consistent with this relationship, relative behavior of the transition metals is not well resolved, being likely obscured by complex bonding processes and the potential participation of Na in the formation of tetra-chloro species. At lower densities (at/near halite saturation) partitioning behavior of all metals becomes highly non-linear, where M/Cl ratios in the vapor begin to increase despite continued decreases in chlorinity and density. We refer to this phenomenon as "volatility", which is broadly associated with substantial increases in the HCl/NaCl ratio (eventually to >1) due to hydrolysis of NaCl. Some transition metals (e.g., Fe, Zn) exhibit volatility prior to halite stability, suggesting a potential shift in vapor speciation relative to nearer critical regions of the vapor-liquid solvus. The chemistry of deep-sea hydrothermal fluids appears affected by this process during magmatic events, however, our results do not support suggestions of subseafloor halite precipitation

  6. Persistent Effectivity of Gas Plasma-Treated, Long Time-Stored Liquid on Epithelial Cell Adhesion Capacity and Membrane Morphology

    PubMed Central

    Hoentsch, Maxi; Bussiahn, René; Rebl, Henrike; Bergemann, Claudia; Eggert, Martin; Frank, Marcus; von Woedtke, Thomas; Nebe, Barbara

    2014-01-01

    Research in plasma medicine includes a major interest in understanding gas plasma-cell interactions. The immediate application of gas plasma in vitro inhibits cell attachment, vitality and cell-cell contacts via the liquid. Interestingly, in our novel experiments described here we found that the liquid-mediated plasma effect is long-lasting after storage up to seven days; i. e. the liquid preserves the characteristics once induced by the argon plasma. Therefore, the complete Dulbecco's Modified Eagle cell culture medium was argon plasma-treated (atmospheric pressure, kINPen09) for 60 s, stored for several days (1, 4 and 7 d) at 37°C and added to a confluent mouse hepatocyte epithelial cell (mHepR1) monolayer. Impaired tight junction architecture as well as shortened microvilli on the cell membrane could be observed, which was accompanied by the loss of cell adhesion capacity. Online-monitoring of vital cells revealed a reduced cell respiration. Our first time-dependent analysis of plasma-treated medium revealed that temperature, hydrogen peroxide production, pH and oxygen content can be excluded as initiators of cell physiological and morphological changes. The here observed persisting biological effects in plasma-treated liquids could open new medical applications in dentistry and orthopaedics. PMID:25170906

  7. Ionic liquids as antimicrobials, solvents, and prodrugs for treating skin disease

    NASA Astrophysics Data System (ADS)

    Zakrewsky, Michael A.

    The skin is the largest organ in the body. It provides a compliant interface for needle-free drug delivery, while avoiding major degradative pathways associated with the GI tract. These can result in improved patient compliance and sustained and controlled release compared to other standard delivery methods such as intravenous injection, subcutaneous injection, and oral delivery. Concurrently, for the treatment of skin related diseases (e.g. bacterial infection, skin cancer, psoriasis, atopic dermatitis, etc.) cutaneous application provides targeted delivery to the disease site, allowing the use of more potent therapeutics with fewer systemic side effects. Unfortunately, the outer layer of the skin -- the stratum corneum (SC) -- presents a significant barrier to most foreign material. This is particularly true for large hydrophilic molecules (>500Da), which must partition through tortuous lipid channels in the SC to penetrate deep tissue layers where the majority of skin-related diseases reside. Interestingly, over the last few decades ionic liquids (ILs) have emerged as a burgeoning class of designer solvents. ILs have been proven beneficial for use in industrial processing, catalysis, pharmaceuticals, and electrochemistry to name a few. The ability to modulate either the cation or anion individually presents an advantageous framework for tuning secondary characteristics without sacrificing the primary function of the IL. Here we report the use of novel ILs for cutaneous drug delivery. Specifically, we demonstrate their potential as potent, broad-spectrum antimicrobials, as solvents for topical delivery of hydrophilic and hydrophobic drugs, and as prodrugs to either reduce the dose-dependent toxicity of drugs that cause skin irritation or enhance delivery of macromolecules into skin and cells. Thus, our results clearly demonstrate ILs holds promise as a transformative platform for treating skin disease.

  8. One-pot hydrothermal preparation of graphene sponge for the removal of oils and organic solvents

    NASA Astrophysics Data System (ADS)

    Wu, Ruihan; Yu, Baowei; Liu, Xiaoyang; Li, Hongliang; Wang, Weixuan; Chen, Lingyun; Bai, Yitong; Ming, Zhu; Yang, Sheng-Tao

    2016-01-01

    Graphene sponge (GS) has found applications in oil removal due to the hydrophobic nature of graphene sheets. Current hydrothermal preparations of GS use toxic reducing reagents, which might cause environmental pollution. In this study, we reported that graphene oxide (GO) could be hydrothermally reduced by glucose to form GS for the adsorption of oils and various organic solvents. Graphene sheets were reduced by glucose during the hydrothermal treatment and formed 3D porous structure. GS efficiently adsorbed organic solvents and oils with competitive adsorption capacities. GS was able to treat pollutants in pure liquid form and also in the simulated seawater. GS could be easily regenerated by evaporating or burning. After 10 cycles, the adsorption capacity still retained 77% by evaporating and 87% by burning. The implication to the applications of GS in water remediation is discussed.

  9. Rapid microwave hydrothermal synthesis of ZnGa{sub 2}O{sub 4} with high photocatalytic activity toward aromatic compounds in air and dyes in liquid water

    SciTech Connect

    Sun Meng; Li Danzhen; Zhang Wenjuan; Chen Zhixin; Huang Hanjie; Li Wenjuan; He Yunhui; Fu Xianzhi

    2012-06-15

    ZnGa{sub 2}O{sub 4} was synthesized from Ga(NO{sub 3}){sub 3} and ZnCl{sub 2} via a rapid and facile microwave-assisted hydrothermal method. The photocatalytic properties of the as-prepared ZnGa{sub 2}O{sub 4} were evaluated by the degradation of pollutants in air and aqueous solution under ultraviolet (UV) light illumination. The results demonstrated that ZnGa{sub 2}O{sub 4} had exhibited efficient photocatalytic activities higher than that of commercial P25 (Degussa Co.) in the degradation of benzene, toluene, and ethylbenzene, respectively. In the liquid phase degradation of dyes (methyl orange, Rhodamine B, and methylene blue), ZnGa{sub 2}O{sub 4} has also exhibited remarkable activities higher than that of P25. After 32 min of UV light irradiation, the decomposition ratio of methyl orange (10 ppm, 150 mL) over ZnGa{sub 2}O{sub 4} (0.06 g) was up to 99%. The TOC tests revealed that the mineralization ratio of MO (10 ppm, 150 mL) was 88.1% after 90 min of reaction. A possible mechanism of the photocatalysis over ZnGa{sub 2}O{sub 4} was also proposed. - Graphical abstract: In the degradation of RhB under UV light irradiation, ZnGa{sub 2}O{sub 4} had exhibited efficient photo-activity, and after only 24 min of irradiation the decomposition ratio was up to 99.8%. Highlights: Black-Right-Pointing-Pointer A rapid and facile M-H method to synthesize ZnGa{sub 2}O{sub 4} photocatalyst. Black-Right-Pointing-Pointer The photocatalyst exhibits high activity toward benzene and dyes. Black-Right-Pointing-Pointer The catalyst possesses more surface hydroxyl sites than TiO{sub 2} (P25). Black-Right-Pointing-Pointer Deep oxidation of different aromatic compounds and dyes over catalyst.

  10. Controlling the alignment of liquid crystals by nanoparticle-doped and UV-treated polyimide alignment films

    NASA Astrophysics Data System (ADS)

    Jeng, Shie-Chang; Hwang, Su-June; Chen, Tai-An; Liu, Han-Shiang; Chen, Mu-Zhe

    2012-03-01

    We have developed two approaches for controlling the pretilt angles of liquid crystal molecules by using conventional polyimide (PI) alignment materials either doping homogeneous PIs with Polyhedral Oligomeric Silsequioxanes (POSS) nanoparticles or treating homeotropic PIs with ultraviolet light. These techniques are very simple and are compatible with current methods familiar in the LCD industry. The characteristics of modified PI alignment films and their applications for photonic devices are demonstrated in this paper.

  11. Process and device for injecting a liquid agent used for treating a geological formation in the vicinity of a well bore traversing this formation

    SciTech Connect

    Colonna, J.; Fitremann, Jm.; Genin, R.; Sarda, Jp.

    1984-02-14

    A technique is disclosed for liquid treating a geological formation. It comprises spraying the liquid with a pressurized carrier gas, using a spraying pipe whose length and diameter are adjusted as a function of the pressure prevailing at the level of the formation and of the characteristics of the injected liquid and the pressurized carrier gas, so that the size of the liquid droplets at the outlet of the spraying pipe has a narrow range of distribution about a single preselected value.

  12. Evaluation of liquid smoke treated ready-to-eat (RTE) meat products for control of Listeria innocua M1.

    PubMed

    Milly, P J; Toledo, R T; Chen, J

    2008-05-01

    Liquid smoke fractions (S1, S2, S3, and S4) were applied on ready-to-eat (RTE) meat products to control the growth of inoculated Listeria innocua M1. Turkey rolls and roast beef products were dipped in liquid smoke, surface inoculated with L. innocua M1 (10(2) CFU/25 cm(2) RTE meat surface), vacuum packaged, and stored at 4 degrees C. Section 8.5 of USDA's detection and isolation procedure for L. monocytogenes was employed in conjunction with a Micro-ID system for L. innocua M1 identification (ID). Products treated with smoke fractions S1, S2, and S3 were negative for L. innocua M1 at 2 and 4 wk during incubation at 4 degrees C. Products treated with S4 were positive for L. innocua M1 immediately following inoculation and after storage for 2 and 4 wk. Smoke fractions S1, S2, and S3 exhibited pH values lower than 4.6, acidity values higher than 1.5%, and carbonyl concentrations higher than 110 mg/mL. All liquid smoke fractions contained similar phenol concentrations (0.3 to 0.6 mg/mL), suggesting that phenols may have a limited role in the bactericidal effects of liquid smoke fractions against specific microorganisms.

  13. Hydrothermal Liquefaction of Biomass

    SciTech Connect

    Elliott, Douglas C.

    2010-12-10

    Hydrothermal liquefaction technology is describes in its relationship to fast pyrolysis of biomass. The scope of work at PNNL is discussed and some intial results are presented. HydroThermal Liquefaction (HTL), called high-pressure liquefaction in earlier years, is an alternative process for conversion of biomass into liquid products. Some experts consider it to be pyrolysis in solvent phase. It is typically performed at about 350 C and 200 atm pressure such that the water carrier for biomass slurry is maintained in a liquid phase, i.e. below super-critical conditions. In some applications catalysts and/or reducing gases have been added to the system with the expectation of producing higher yields of higher quality products. Slurry agents ('carriers') evaluated have included water, various hydrocarbon oils and recycled bio-oil. High-pressure pumping of biomass slurry has been a major limitation in the process development. Process research in this field faded away in the 1990s except for the HydroThermal Upgrading (HTU) effort in the Netherlands, but has new resurgence with other renewable fuels in light of the increased oil prices and climate change concerns. Research restarted at Pacific Northwest National Laboratory (PNNL) in 2007 with a project, 'HydroThermal Liquefaction of Agricultural and Biorefinery Residues' with partners Archer-Daniels-Midland Company and ConocoPhillips. Through bench-scale experimentation in a continuous-flow system this project investigated the bio-oil yield and quality that could be achieved from a range of biomass feedstocks and derivatives. The project was completed earlier this year with the issuance of the final report. HydroThermal Liquefaction research continues within the National Advanced Biofuels Consortium with the effort focused at PNNL. The bench-scale reactor is being used for conversion of lignocellulosic biomass including pine forest residue and corn stover. A complementary project is an international collaboration with

  14. Optimization of hydrothermal pretreatment of lignocellulosic biomass in the bioethanol production process.

    PubMed

    Nitsos, Christos K; Matis, Konstantinos A; Triantafyllidis, Kostas S

    2013-01-01

    The natural resistance to enzymatic deconstruction exhibited by lignocellulosic materials has designated pretreatment as a key step in the biological conversion of biomass to ethanol. Hydrothermal pretreatment in pure water represents a challenging approach because it is a method with low operational costs and does not involve the use of organic solvents, difficult to handle chemicals, and "external" liquid or solid catalysts. In the present work, a systematic study has been performed to optimize the hydrothermal treatment of lignocellulosic biomass (beech wood) with the aim of maximizing the enzymatic digestibility of cellulose in the treated solids and obtaining a liquid side product that could also be utilized for the production of ethanol or valuable chemicals. Hydrothermal treatment experiments were conducted in a batch-mode, high-pressure reactor under autogeneous pressure at varying temperature (130-220 °C) and time (15-180 min) regimes, and at a liquid-to-solid ratio (LSR) of 15. The intensification of the process was expressed by the severity factor, log R(o). The major changes induced in the solid biomass were the dissolution/removal of hemicellulose to the process liquid and the partial removal and relocation of lignin on the external surface of biomass particles in the form of recondensed droplets. The above structural changes led to a 2.5-fold increase in surface area and total pore volume of the pretreated biomass solids. The enzymatic hydrolysis of cellulose to glucose increased from less than 7 wt% for the parent biomass to as high as 70 wt% for the treated solids. Maximum xylan recovery (60 wt%) in the hydrothermal process liquid was observed at about 80 wt% hemicellulose removal; this was accomplished by moderate treatment severities (log R(o)=3.8-4.1). At higher severities (log R(o)=4.7), xylose degradation products, mainly furfural and formic acid, were the predominant chemicals formed. PMID:23180649

  15. Anaerobic digestion of yard waste with hydrothermal pretreatment.

    PubMed

    Li, Wangliang; Zhang, Guangyi; Zhang, Zhikai; Xu, Guangwen

    2014-03-01

    The digestibility of lignocellulosic biomass is limited by its high content of refractory components. The objective of this study is to investigate hydrothermal pretreatment and its effects on anaerobic digestion of sorted organic waste with submerged fermentation. Hydrothermal pretreatment (HT) was performed prior to anaerobic digestion, and three agents were examined for the HT: hot compressed water, alkaline solution, and acidic solution. The concentrations of glucose and xylose were the highest in the sample pretreated in acidic solution. Compared with that of the untreated sample, the biogas yields from digesting the samples pretreated in alkaline solution, acidic solution, and hot water increased by 364, 107, and 79%, respectively. The decrease of chemical oxygen demand (COD) in liquid phase followed the same order as for the biogas yield. The initial ammonia content of the treated samples followed the order sample treated in acidic solution > sample treated in alkaline solution > sample treated in hot water. The concentrations of volatile fatty acids (VFAs) were low, indicating that the anaerobic digestion process was running at continuously stable conditions.

  16. Anhydrite Solubility and Ca Isotope Fractionation in the Vapor-Liquid Field of the NaCl-H2O System: Implications for Hydrothermal Vent Fluids at Mid-ocean Ridges

    NASA Astrophysics Data System (ADS)

    Scheuermann, P.; Syverson, D. D.; Higgins, J. A.; Seyfried, W. E., Jr.

    2015-12-01

    Hydrothermal experiments were performed at 410, 420 and 450°C between 180-450 bar to investigate anhydrite (CaSO4) solubility and Ca isotope fractionation in the liquid-vapor stability field of the NaCl-H2O system. Experiments were conducted in flexible gold reaction cells and a fixed volume Ti reactor to reach all pressures between the critical curve and three-phase boundary. During isothermal decompression at 410°C, anhydrite solubility in the liquid phase increases (1 to 9 mmol/kg Ca), whereas the solubility decreases in the vapor phase (130 to < 10 umol/kg Ca). At 410°C and 290-270 bar, the partition coefficient, log Km = log (mv / ml), for Ca decreases from -1.35 to -2.46, and that of SO4 decreases from -1.76 to -2.82. At 420°C the Ca:SO4 ratio of the starting solution was 2:1, and the pH25°C decreases in the liquid and increases in the vapor upon decompression. Ca hydrolysis in the liquid and complex interactions between undetermined aqueous species in the vapor could explain this pattern. At 410 and 450°C, the experiments started with a Ca:SO4 ratio of 1:1. Along the 410°C isotherm, pH25°C initially increases in both the liquid and vapor, potentially caused by precipitation of an H+ bearing salt, such as NaHSO4. 30-40 bar below the critical curve there is a sudden decrease in pH25°C as the putative salt phase may become unstable and dissolve. At 450°C, pH25°C decreases in the vapor and increases in the liquid, as HCl and H2SO4 partition into the vapor. Ca isotope data at 420°C between 375-300 bar indicate that the vapor is isotopically light relative to the liquid. At lower pressures both phases approach the isotopic composition of the coexisting anhydrite, suggesting that dissolved Ca speciation becomes more structurally similar to anhydrite. This study furthers our understanding of elemental partitioning and isotopic fractionation in mineral-fluid systems with implications for mass transfer reactions at/near the magma-hydrothermal boundary at

  17. Hydrothermalism in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Dando, P. R.; Stüben, D.; Varnavas, S. P.

    1999-08-01

    Hydrothermalism in the Mediterranean Sea results from the collision of the African and European plates, with the subduction of the oceanic part of the African plate below Europe. High heat flows in the resulting volcanic arcs and back-arc extensional areas have set-up hydrothermal convection systems. Most of the known hydrothermal sites are in shallow coastal waters, <200 m depth, so that much of the reported fluid venting is of the gasohydrothermal type. The hydrothermal liquids are of varying salinities, both because of phase separation as a result of seawater boiling at the low pressures and because of significant inputs of rainfall into the hydrothermal reservoirs at some sites. The major component of the vented gas is carbon dioxide, with significant quantities of sulphur dioxide, hydrogen sulphide, methane and hydrogen also being released. Acid leaching of the underlying rocks leads to the mobilisation of heavy metals, many of which are deposited sub-surface although there is a conspicuous enrichment of metals in surficial sediments in venting areas. Massive polymetalic sulphides have been reported from some sites. No extant vent-specific fauna have been described from Mediterranean sites. There is a reduced diversity of fauna within the sediments at the vents. In contrast, a high diversity of epifauna has been reported and the vent sites are areas of settlement for exotic thermophilic species. Large numbers of novel prokaryotes, especially hyperthermophilic crenarchaeota, have been isolated from Mediterranean hydrothermal vents. However, their distribution in the subsurface biosphere and their role in the biogeochemistry of the sites has yet to be studied.

  18. Ion exchange materials, method of forming ion exchange materials, and methods of treating liquids

    DOEpatents

    Wertsching, Alan K.; Peterson, Eric S.; Wey, John E.

    2007-12-25

    The invention includes an ion affinity material having an organic component which is sulfonated and which is chemically bonded to an inorganic substrate component. The invention includes a method of forming a metal binding material. A solid support material comprising surface oxide groups is provided and an organic component having at least one alkyl halide is covalently linked to at least some of the surface oxide groups to form a modified support material. The at least one alkyl halide is subsequently converted into an alkyl sulfonate. The invention further includes a method and system for extracting ions from a liquid. An ion exchange material having a sulfonated alkyl silane component covalently bonded to a metal oxide support material is provided and a liquid is exposed to the ion exchange material.

  19. Hydrothermal alteration features in the Vargeão basaltic impact structure (South Brazil): Implications about the presence of liquid water in Mars

    NASA Astrophysics Data System (ADS)

    Yokoyama, E.; Nédélec, A.; Baratoux, D.; Berger, G.; Trindade, R. I.

    2013-05-01

    This study presents new petrological data about the hydrothermal fluid percolation in impact craters. Impact cratering process is of primary importance in the evolution of solid bodies of the Solar System. However, impact craters on basaltic rocks, which are the best analog for the surface of other planets and satellites, are rare on Earth. Recently, one medium-size complex crater was identified on volcanic rocks of the Paraná basin (south Brazil), providing an additional analog for the craters of most rocky planets and satellites. The 12 km wide Vargeão is a complex impact structure formed on volcanics rocks of the Serra Geral Formation (about 133-131 Ma), which are locally intertrapped by aeolian-sandstones of Botucatu Formation. Vargeão is morphologically characterized by a well-preserved rim and a smoothed central uplift. The rim region is characterized by concentric gravitational faults that affect tholeiitic basalt flows hundreds of meters thick and rhyodacites few tens of meters thick. Associated with these faults occur the formation of local networks of small red breccia veins. The central uplift has fractured basaltic rocks that contain a lot of red oxidized breccias veins cutted by some white veins. This study is focused on the petrogenesis of these centimeter breccia veins that are found in all lithologies. We conducted a detailed petrological study (petrography, microprobe, SEM, Raman spectroscopy, Magnetic data, Spectroscopy of reflectance and XRD) on these veins and their host-rocks. Our results show that the veins were strongly affected by the post-impact hydrothermal fluids. The hydrothermal alteration varies geographically in the structure. On the rim area this alteration consists of total or partial substitution of the melt matrix by quartz, calcite, iron oxides, zeolites and clay minerals. At the central area, the alteration mineral assembly is composed of quartz, iron oxides, zeolites, clay minerals and rarely calcite. Usually, the alteration

  20. Hydrothermal treatment of MSWI bottom ash forming acid-resistant material.

    PubMed

    Etoh, Jiro; Kawagoe, Takeshi; Shimaoka, Takayuki; Watanabe, Koichiro

    2009-03-01

    To recycle municipal solid waste incinerator (MSWI) bottom ash, synthesis of hydrothermal minerals from bottom ash was performed to stabilize heavy metals. MSWI bottom ash was mixed with SiO(2), Al(OH)(3), and Mg(OH)(2) so its chemical composition was similar to that of hydrothermal clay minerals. These solid specimens were mixed with water at a liquid/solid ratio of 5. The reaction temperature was 200 degrees C, and reactions were performed for 24-240h. Generation of kaolinite/smectite mixed-layer clay mineral was found in the samples after the reaction of the mixture of bottom ash, SiO(2), and Mg(OH)(2). Calcium silicate hydrate minerals such as tobermorite and xonotlite were also generated. X-ray powder diffraction suggested the presence of amorphous materials. Leaching tests at various pHs revealed that the concentration of heavy metals in the leachates from MSWI bottom ash hydrothermally treated with SiO(2) and Mg(OH)(2) was lower than that in leachates from non-treated bottom ash, especially under acid conditions. Hydrothermal treatment with modification of chemical composition may have potential for the recycling of MSWI bottom ash. PMID:18845427

  1. Hydrothermal treatment of MSWI bottom ash forming acid-resistant material

    SciTech Connect

    Etoh, Jiro Kawagoe, Takeshi; Shimaoka, Takayuki; Watanabe, Koichiro

    2009-03-15

    To recycle municipal solid waste incinerator (MSWI) bottom ash, synthesis of hydrothermal minerals from bottom ash was performed to stabilize heavy metals. MSWI bottom ash was mixed with SiO{sub 2}, Al(OH){sub 3}, and Mg(OH){sub 2} so its chemical composition was similar to that of hydrothermal clay minerals. These solid specimens were mixed with water at a liquid/solid ratio of 5. The reaction temperature was 200 deg. C, and reactions were performed for 24-240 h. Generation of kaolinite/smectite mixed-layer clay mineral was found in the samples after the reaction of the mixture of bottom ash, SiO{sub 2}, and Mg(OH){sub 2}. Calcium silicate hydrate minerals such as tobermorite and xonotlite were also generated. X-ray powder diffraction suggested the presence of amorphous materials. Leaching tests at various pHs revealed that the concentration of heavy metals in the leachates from MSWI bottom ash hydrothermally treated with SiO{sub 2} and Mg(OH){sub 2} was lower than that in leachates from non-treated bottom ash, especially under acid conditions. Hydrothermal treatment with modification of chemical composition may have potential for the recycling of MSWI bottom ash.

  2. Silica Transport and Distribution in Saline, Immiscible Fluids: Application to Subseafloor Hydrothermal Systems

    NASA Astrophysics Data System (ADS)

    Steele-Macinnis, M.; Bodnar, R. J.; Lowell, R.; Rimstidt, J. D.

    2009-05-01

    systems to predict the evolution of silica distribution in time and space in these systems. Preliminary runs illustrate a significant effect of salinity in the evolving and boiling system on silica solubility. The model predicts that silica solubility is progressively enhanced in the two-phase liquid-plus-vapor region as brine is concentrated by the preferential loss of vapor. The model also predicts that there is a narrow region of intense quartz deposition in the deep part of the upflow zone, where the fluid reenters the one-phase field. The model currently treats the wallrock as an infinite quartz reservoir, but future work will fully couple the quartz solubility and fluid flow models, to allow porosity adjustment and resultant permeability evolution by quartz dissolution and precipitation. This work was supported in part by the Institute for Critical Technology and Applied Sciences (ICTAS) at Virginia Tech

  3. Effects of process parameters on hydrothermal carbonization

    NASA Astrophysics Data System (ADS)

    Uddin, Md. Helal

    In recent years there has been increased research activity in renewable energy, especially upgrading widely available lignicellulosic biomass, in a bid to counter the increasing environmental concerns related with the use of fossil fuels. Hydrothermal carbonization (HTC), also known as wet torrefaction or hot water pretreatment, is a process for pretreatment of diverse lignocellulosic biomass feedstocks, where biomass is treated under subcritical water conditions in short contact time to produce high-value products. The products of this process are: a solid mass characterized as biochar/biocoal/biocarbon, which is homogeneous, energy dense, and hydrophobic; a liquid stream composed of five and six carbon sugars, various organic acids, and 5-HMF; and a gaseous stream, mainly CO2. A number of process parameters are considered important for the extensive application of the HTC process. Primarily, reaction temperature determines the characteristics of the products. In the solid product, the oxygen carbon ratio decreases with increasing reaction temperature and as a result, HTC biochar has the similar characteristics to low rank coal. However, liquid and gaseous stream compositions are largely correlated with the residence time. Biomass particle size can also limit the reaction kinetics due to the mass transfer effect. Recycling of process water can help to minimize the utility consumption and reduce the waste treatment cost as a result of less environmental impact. Loblolly pine was treated in hot compressed water at 200 °C, 230 °C, and 260 °C with 5:1 water:biomass mass ratio to investigate the effects of process parameters on HTC. The solid product were characterized by their mass yields, higher heating values (HHV), and equilibrium moisture content (EMC), while the liquid were characterized by their total organic carbon content and pH value.

  4. Topochemical and morphological characterization of wood cell wall treated with the ionic liquid, 1-ethylpyridinium bromide.

    PubMed

    Kanbayashi, Toru; Miyafuji, Hisashi

    2015-09-01

    MAIN CONCLUSION : [EtPy][Br] is more reactive toward lignin than toward the PSs in wood cell walls, and [EtPy][Br] treatment results in inhomogenous changes to the cell wall's ultrastructural and chemical components. The effects of the ionic liquid 1-ethylpyridinium bromide ([EtPy][Br]), which prefers to react with lignin rather than cellulose on the wood cell walls of Japanese cedar (Cryptomeria japonica), were investigated from a morphology and topochemistry point of view. The [EtPy][Br] treatment induced cell wall swelling, the elimination of warts, and the formation of countless pores in the tracheids. However, many of the pit membranes and the cellulose crystalline structure remained unchanged. Raman microscopic analyses revealed that chemical changes in the cell walls were different for different layers and that the lignin in the compound middle lamella and the cell corner resists interaction with [EtPy][Br]. Additionally, the interaction of [EtPy][Br] with the wood cell wall is different to that of other types of ionic liquid. PMID:25556160

  5. A model for treating polluted air streams in a continuous two liquid phase stirred tank bioreactor.

    PubMed

    Fazaelipoor, Mohammad Hassan

    2007-09-01

    Biological air treatment systems have been widely under investigation in recent years. Inclusion of non-biodegradable organic solvents to these systems is a way to improve the biotic removal capacity of the systems. In this article the process of absorption and biodegradation of a hydrophobic organic compound in a two liquid phase stirred tank bioreactor has been modeled. Using the model it has been shown that the inclusion of an organic solvent is advantageous if certain conditions are met. Some simulation examples showed that the usefulness of adding an organic solvent to the system depends on kinetic parameters of biological reactions and mass transfer coefficients of pollutants and oxygen between the air and liquid phases. Since different factors influence the process, the usefulness of including an organic solvent to the system should be checked in each special case. The simple model presented in this article can help the prediction of the effect of amending a solvent to the bioreactor under a set of given conditions.

  6. Biosensors for liquid biopsy: circulating nucleic acids to diagnose and treat cancer.

    PubMed

    Bellassai, Noemi; Spoto, Giuseppe

    2016-10-01

    The detection of cancer biomarkers freely circulating in blood offers new opportunities for cancer early diagnosis, patient follow-up, and therapy efficacy assessment based on liquid biopsy. In particular, circulating cell-free nucleic acids released from tumor cells have recently attracted great attention also because they become detectable in blood before the appearance of other circulating biomarkers, such as circulating tumor cells. The detection of circulating nucleic acids poses several technical challenges that arise from their low concentration and relatively small size. Here, possibilities offered by innovative biosensing approaches for the detection of circulating DNA in peripheral blood and blood-derived products such as plasma and serum blood are discussed. Different transduction principles are used to detect circulating DNAs and great advantages are derived from the combined use of nanostructured materials.

  7. Reed's Syndrome: A Case of Multiple Cutaneous Leiomyomas Treated with Liquid Nitrogen Cryotherapy

    PubMed Central

    Basendwh, Mohammad A.; Fatani, Mohammad; Baltow, Badee

    2016-01-01

    Reed's syndrome is an autosomal dominant genetic disorder. Affected individuals are at increased risk of developing benign smooth muscle tumors in the skin and uterus. In this article, we report a case of a 52-year-old female who presented to our dermatology clinic complaining of painful skin lesions on her right arm, left forearm and trunk. The patient had a past medical history of uterine leiomyomatosis for which she underwent hysterectomy 17 years ago. The patient's family history revealed that her mother, 2 sisters and 2 maternal aunts also had uterine leiomyomas. The diagnosis of Reed's syndrome was confirmed by histopathologic examination of the patient's dermal lesion in conjunction with her surgical and family histories. Five years after the initial presentation, the patient underwent treatment with liquid nitrogen cryotherapy for the dermal leiomyomas. After the treatment, marked improvement was noticed with regard to the pain and size of the skin lesions. PMID:27064320

  8. Reed's Syndrome: A Case of Multiple Cutaneous Leiomyomas Treated with Liquid Nitrogen Cryotherapy.

    PubMed

    Basendwh, Mohammad A; Fatani, Mohammad; Baltow, Badee

    2016-01-01

    Reed's syndrome is an autosomal dominant genetic disorder. Affected individuals are at increased risk of developing benign smooth muscle tumors in the skin and uterus. In this article, we report a case of a 52-year-old female who presented to our dermatology clinic complaining of painful skin lesions on her right arm, left forearm and trunk. The patient had a past medical history of uterine leiomyomatosis for which she underwent hysterectomy 17 years ago. The patient's family history revealed that her mother, 2 sisters and 2 maternal aunts also had uterine leiomyomas. The diagnosis of Reed's syndrome was confirmed by histopathologic examination of the patient's dermal lesion in conjunction with her surgical and family histories. Five years after the initial presentation, the patient underwent treatment with liquid nitrogen cryotherapy for the dermal leiomyomas. After the treatment, marked improvement was noticed with regard to the pain and size of the skin lesions. PMID:27064320

  9. Whole Algae Hydrothermal Liquefaction: 2014 State of Technology

    SciTech Connect

    Jones, Susanne B.; Zhu, Yunhua; Snowden-Swan, Lesley J.; Anderson, Daniel; Hallen, Richard T.; Schmidt, Andrew J.; Albrecht, Karl O.; Elliott, Douglas C.

    2014-07-30

    This report describes the base case yields and operating conditions for converting whole microalgae via hydrothermal liquefaction and upgrading to liquid fuels. This serves as the basis against which future technical improvements will be measured.

  10. A simple recovery process for biodegradable plastics accumulated in cyanobacteria treated with ionic liquids.

    PubMed

    Kobayashi, Daigo; Fujita, Kyoko; Nakamura, Nobuhumi; Ohno, Hiroyuki

    2015-02-01

    Here, we proposed a simple recovery process for poly(3-hydroxybutyrate) (PHB) accumulated in cyanobacteria by using ionic liquids (ILs), which dissolve cyanobacteria but not PHB. First, we investigated the effects of IL polarity on hydrogen-bonding receipt ability (β value) and hydrogen-bonding donating ability (α value) and evaluated the subsequent dissolution of cyanobacteria. We found that ILs having α values higher than approximately 0.4 and β values of approximately 0.9 were suitable for dissolution of cyanobacteria. In particular, 1-ethyl-3-methylimidazolium methylphosphonate ([C2mim][MeO(H)PO2]) was found to dissolve cyanobacteria components, but not PHB. Thus, we verified that PHB produced in cyanobacteria could be separated and recovered by simple filtering after dissolution of cyanobacteria in [C2mim][MeO(H)PO2]. Using this technique, more than 98 % of PHB was obtained on the filter as residues separated from cyanobacteria. Furthermore, [C2mim][MeO(H)PO2] maintained the ability to dissolve cyanobacteria after a simple recycling procedure.

  11. Posaconazole liquid suspension in solid organ transplant recipients previously treated with voriconazole

    PubMed Central

    Shoham, S.; Ostrander, D.; Marr, K.

    2015-01-01

    Background Posaconazole (PCZ) has become an attractive alternative to voriconazole (VCZ) in transplant recipients with suspected or proven invasive filamentous fungal infections, given fewer drug interactions. Here, we describe our experience with PCZ after VCZ in solid organ transplant (SOT) recipients. Methods VCZ was replaced by PCZ liquid solution in 19 SOT recipients (15 lung, 2 kidney, 1 liver, and 1 heart/lung) with invasive pulmonary aspergillosis (12/19; 63.2%), possible invasive pulmonary fungal infection (2/19; 10.5%), prophylaxis (2/19; 10.5%), or pulmonary scedosporiosis, mucormycosis, and mixed fungal species (1 each). Rationales for switch were suspected adverse reactions to VCZ (17/19; 89.4 %) and desire to broaden spectrum of coverage to include agents of mucormycosis (3/19; 15.8 %). Results PCZ was well tolerated in all patients. In those patients with baseline liver enzyme abnormalities, a median change occurred in concentrations of alanine transaminase (–20 IU/L), aspartate aminotransferase (–17.5 IU/L), and alkaline phosphatase (–61.5 IU/L). Clinical success (resolution, stabilization, or prevention of infection) was achieved in 16/19 (84%) people. Conclusion PCZ appears to have a reasonable safety and tolerability profile and may be an effective alternative in SOT patients who require an agent with anti-mold activity, but are unable to tolerate VCZ. PMID:25846433

  12. Homogeneous liquid crystal alignment characteristics on solution-derived HfYGaO films treated with IB irradiation.

    PubMed

    Lee, Yun-Gun; Park, Hong-Gyu; Jeong, Hae-Chang; Lee, Ju Hwan; Heo, Gi-Seok; Seo, Dae-Shik

    2015-06-29

    Solution-derived HfYGaO films have been treated by ion beam (IB) irradiation and used as liquid crystal (LC) alignment layers. Solution processing was adopted due to its simplicity, high throughput, and facile composition modification. Homogeneous and uniform LC alignment was achieved on the IB-irradiated HfYGaO films, and when these films were adopted in twisted nematic (TN) cells, electro-optical performance comparable to that of TN cells with conventional polyimide layers was achieved, with almost no capacitance-voltage hysteresis. Moreover, LC cells based on IB-irradiated HfYGaO films had a high thermal budget. The proposed IB-irradiated solution-derived HfYGaO films have considerable potential for use in advanced LC applications.

  13. Liquid biopsy-based clinical research in early breast cancer: The EORTC 90091-10093 Treat CTC trial.

    PubMed

    Ignatiadis, Michail; Rack, Brigitte; Rothé, Francoise; Riethdorf, Sabine; Decraene, Charles; Bonnefoi, Hervé; Dittrich, Christian; Messina, Carlo; Beauvois, Melanie; Trapp, Elisabeth; Goulioti, Theodora; Tryfonidis, Konstantinos; Pantel, Klaus; Repollet, Madeline; Janni, Wolfgang; Piccart, Martine; Sotiriou, Christos; Litiere, Saskia; Pierga, Jean-Yves

    2016-08-01

    There is increasing evidence that breast cancer evolves over time under the selection pressure of systemic treatment. Today, treatment decisions in early breast cancer are based on primary tumour characteristics without considering the disease evolution. Chemoresistant micrometastatic disease is poorly characterised and thus it is not used in current clinical practice as a tool to personalise treatment approaches. The detection of chemoresistant circulating tumour cells (CTCs) has been shown to be associated with worse prognosis in early breast cancer. The ongoing Treat CTC trial is the first international, liquid biopsy-based trial evaluating the concept of targeting chemoresistant minimal residual disease: detection of CTCs following adjuvant chemotherapy (adjuvant cohort) or neoadjuvant chemotherapy in patients who did not achieve pathological complete response (neoadjuvant cohort). This article presents the rational and design of this trial and the results of the pilot phase after 350 patients have been screened and provides insights that might provide information for future trials using the liquid biopsy approach as a tool towards precision medicine (NCT01548677). PMID:27289552

  14. Hyperbaric Hydrothermal Atomic Force Microscope

    DOEpatents

    Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

    2003-07-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  15. Hyperbaric hydrothermal atomic force microscope

    DOEpatents

    Knauss, Kevin G.; Boro, Carl O.; Higgins, Steven R.; Eggleston, Carrick M.

    2002-01-01

    A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

  16. Hydrothermally mixed hydroxyapatite-multiwall carbon nanotubes composite coatings on biomedical alloys by electrophoretic deposition.

    PubMed

    Ustundag, C B; Avciata, O; Kaya, F; Kaya, C

    2013-02-14

    Hydroxyapatite (HA) coatings have been used to improve biological and mechanical fixation of metallic prosthesis. Because of extraordinary features of carbon nanotubes (CNTs), they have a lot of facilities, such as extremely strong nanoreinforcement materials for composites. HA powders were synthesized and mixed with multiwalled carbon nanotubes (MWCNTs) by a hydrothermal process. Calcium acetate (Ca (CH(3)COO)(2)) and phosphoric acid (H(3)PO(4)) were used as starting materials for synthesizing nano-HA powders. HA-MWCNTs were treated together hydrothermally at 200 °C for 2 h to synthesize nano-HA powders mixed homogeneously with MWCNTs. Cathodic deposits were obtained on Ti-based alloys using suspensions containing nano-HA and MWCNTs dispersed in n-butanol solvent. It was shown that MWCNTs interacted with HA powders during hydrothermal processing, and therefore, they can easily be dispersed within aqueous-based suspensions. It was also shown that hydrothermal surface modification of MWCNTs with functional groups was achievable, which was a significant step toward eliminating nonwetting surface behavior of MWCNTs, resulting in obtaining homogeneous dispersion of them in liquids.

  17. Hydrothermal organic synthesis experiments

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.

    1992-01-01

    Ways in which heat is useful in organic synthesis experiments are described, and experiments on the hydrothermal destruction and synthesis of organic compounds are discussed. It is pointed out that, if heat can overcome kinetic barriers to the formation of metastable states from reduced or oxidized starting materials, abiotic synthesis under hydrothermal conditions is a distinct possibility. However, carefully controlled experiments which replicate the descriptive variables of natural hydrothermal systems have not yet been conducted with the aim of testing the hypothesis of hydrothermal organic systems.

  18. METEORIC-HYDROTHERMAL SYSTEMS.

    USGS Publications Warehouse

    Criss, Robert E.; Taylor, Hugh P.

    1986-01-01

    This paper summarizes the salient characteristics of meteoric-hydrothermal systems, emphasing the isotopic systematics. Discussions of permeable-medium fluid dynamics and the geology and geochemistry of modern geothermal systems are also provided, because they are essential to any understanding of hydrothermal circulation. The main focus of the paper is on regions of ancient meteoric-hydrothermal activity, which give us information about the presently inaccessible, deep-level parts of modern geothermal systems. It is shown oxygen and hydrogen isotopes provide a powerful method to discover and map fossil hydrothermal systems and to investigate diverse associated aspects of rock alteration and ore deposition.

  19. Ongoing hydrothermal activities within Enceladus.

    PubMed

    Hsu, Hsiang-Wen; Postberg, Frank; Sekine, Yasuhito; Shibuya, Takazo; Kempf, Sascha; Horányi, Mihály; Juhász, Antal; Altobelli, Nicolas; Suzuki, Katsuhiko; Masaki, Yuka; Kuwatani, Tatsu; Tachibana, Shogo; Sirono, Sin-iti; Moragas-Klostermeyer, Georg; Srama, Ralf

    2015-03-12

    Detection of sodium-salt-rich ice grains emitted from the plume of the Saturnian moon Enceladus suggests that the grains formed as frozen droplets from a liquid water reservoir that is, or has been, in contact with rock. Gravitational field measurements suggest a regional south polar subsurface ocean of about 10 kilometres thickness located beneath an ice crust 30 to 40 kilometres thick. These findings imply rock-water interactions in regions surrounding the core of Enceladus. The resulting chemical 'footprints' are expected to be preserved in the liquid and subsequently transported upwards to the near-surface plume sources, where they eventually would be ejected and could be measured by a spacecraft. Here we report an analysis of silicon-rich, nanometre-sized dust particles (so-called stream particles) that stand out from the water-ice-dominated objects characteristic of Saturn. We interpret these grains as nanometre-sized SiO2 (silica) particles, initially embedded in icy grains emitted from Enceladus' subsurface waters and released by sputter erosion in Saturn's E ring. The composition and the limited size range (2 to 8 nanometres in radius) of stream particles indicate ongoing high-temperature (>90 °C) hydrothermal reactions associated with global-scale geothermal activity that quickly transports hydrothermal products from the ocean floor at a depth of at least 40 kilometres up to the plume of Enceladus. PMID:25762281

  20. Ongoing hydrothermal activities within Enceladus.

    PubMed

    Hsu, Hsiang-Wen; Postberg, Frank; Sekine, Yasuhito; Shibuya, Takazo; Kempf, Sascha; Horányi, Mihály; Juhász, Antal; Altobelli, Nicolas; Suzuki, Katsuhiko; Masaki, Yuka; Kuwatani, Tatsu; Tachibana, Shogo; Sirono, Sin-iti; Moragas-Klostermeyer, Georg; Srama, Ralf

    2015-03-12

    Detection of sodium-salt-rich ice grains emitted from the plume of the Saturnian moon Enceladus suggests that the grains formed as frozen droplets from a liquid water reservoir that is, or has been, in contact with rock. Gravitational field measurements suggest a regional south polar subsurface ocean of about 10 kilometres thickness located beneath an ice crust 30 to 40 kilometres thick. These findings imply rock-water interactions in regions surrounding the core of Enceladus. The resulting chemical 'footprints' are expected to be preserved in the liquid and subsequently transported upwards to the near-surface plume sources, where they eventually would be ejected and could be measured by a spacecraft. Here we report an analysis of silicon-rich, nanometre-sized dust particles (so-called stream particles) that stand out from the water-ice-dominated objects characteristic of Saturn. We interpret these grains as nanometre-sized SiO2 (silica) particles, initially embedded in icy grains emitted from Enceladus' subsurface waters and released by sputter erosion in Saturn's E ring. The composition and the limited size range (2 to 8 nanometres in radius) of stream particles indicate ongoing high-temperature (>90 °C) hydrothermal reactions associated with global-scale geothermal activity that quickly transports hydrothermal products from the ocean floor at a depth of at least 40 kilometres up to the plume of Enceladus.

  1. Characterization of advanced preprocessed materials (Hydrothermal)

    SciTech Connect

    Rachel Emerson; Garold Gresham

    2012-09-01

    The initial hydrothermal treatment parameters did not achieve the proposed objective of this effort; the reduction of intrinsic ash in the corn stover. However, liquid fractions from the 170°C treatments was indicative that some of the elements routinely found in the ash that negatively impact the biochemical conversion processes had been removed. After reviewing other options for facilitating ash removal, sodium-citrate (chelating agent) was included in the hydrothermal treatment process, resulting in a 69% reduction in the physiological ash. These results indicated that chelation –hydrothermal treatment is one possible approach that can be utilized to reduce the overall ash content of feedstock materials and having a positive impact on conversion performance.

  2. Hydrothermal treatment of electric arc furnace dust.

    PubMed

    Yu, Bing-Sheng; Wang, Yuh-Ruey; Chang, Tien-Chin

    2011-06-15

    In this study, ZnO crystals were fabricated from electric arc furnace dust (EAFD) after alkaline leaching, purification and hydrothermal treatment. The effects of temperature, duration, pH, and solid/liquid ratio on ZnO crystal morphology and size were investigated. Results show a high reaction temperature capable of accelerating the dissolution of ZnO precursor, expediting the growth of 1D ZnO, and increasing the L/D ratio in the temperature range of 100-200°C. ZnO crystals with high purity can also be obtained, using the one-step hydrothermal treatment with a baffle that depends on the different solubility of zincite and franklinite in the hydrothermal conditions.

  3. Core Cracking and Hydrothermal Circulation Profoundly Affect Ceres' Geophysical Evolution

    NASA Astrophysics Data System (ADS)

    Neveu, Marc; Desch, Steven J.; Castillo-Rogez, Julie C.

    2014-11-01

    The dwarf planet (1)Ceres is about to be visited by the Dawn spacecraft [1]. In addition to a recent report of water vapor emission [2], observations and models of Ceres suggest that its evolution was shaped by interactions between liquid water and silicate rock [3,4].Hydrothermal processes in a heated core require both fractured rock and liquid. Using a new core cracking model coupled to a thermal evolution code [5], we find volumes of fractured rock always large enough for significant interaction to occur. Therefore, liquid persistence is key. It is favored by antifreezes such as ammonia [4], by silicate dehydration which releases liquid, and by hydrothermal circulation itself, which enhances heat transport into the hydrosphere. The heating effect from silicate hydration seems minor. Hydrothermal circulation can profoundly affect Ceres' evolution: it prevents core dehydration via “temperature resets”, global cooling events lasting ~50 Myr, followed by ~1 Gyr periods during which Ceres' interior is nearly isothermal and its hydrosphere largely liquid. Whether Ceres has experienced such extensive hydrothermalism may be determined through examination of its present-day structure. A large, fully hydrated core (radius 420 km) suggests that extensive hydrothermal circulation prevented core dehydration. A small, dry core (radius 350 km) suggests early dehydration from short-lived radionuclides, with shallow hydrothermalism at best. Intermediate structures with a partially dehydrated core seem ambiguous, compatible both with late partial dehydration without hydrothermal circulation, and with early dehydration with extensive hydrothermal circulation. Thus, gravity measurements by the Dawn orbiter [1] could help discriminate between scenarios for Ceres' evolution.References:[1] Russell C. T. & Raymond C. A. (2011) Sp. Sci. Rev. 163, 3-23.[2] Küppers M. et al. (2014) Nature 505, 525-527.[3] Rivkin A. et al. (2011) Sp. Sci. Rev. 163, 95-116.[4] Castillo-Rogez J. C. & Mc

  4. Tuning photoluminescence of organic rubrene nanoparticles through a hydrothermal process

    PubMed Central

    2011-01-01

    Light-emitting 5,6,11,12-tetraphenylnaphthacene (rubrene) nanoparticles (NPs) prepared by a reprecipitation method were treated hydrothermally. The diameters of hydrothermally treated rubrene NPs were changed from 100 nm to 2 μm, depending on hydrothermal temperature. Photoluminescence (PL) characteristics of rubrene NPs varied with hydrothermal temperatures. Luminescence of pristine rubrene NPs was yellow-orange, and it changed to blue as the hydrothermal temperature increased to 180°C. The light-emitting color distribution of the NPs was confirmed using confocal laser spectrum microscope. As the hydrothermal temperature increased from 110°C to 160°C, the blue light emission at 464 to approximately 516 nm from filtered-down NPs was enhanced by H-type aggregation. Filtered-up rubrene NPs treated at 170°C and 180°C exhibited blue luminescence due to the decrease of intermolecular excimer densities with the rapid increase in size. Variations in PL of hydrothermally treated rubrene NPs resulted from different size distributions of the NPs. PMID:21711925

  5. Ancient Hydrothermal Springs in Arabia Terra, Mars

    NASA Technical Reports Server (NTRS)

    Oehler, Dorothy Z.; Allen, Carlton C.

    2008-01-01

    Hydrothermal springs are important astrobiological sites for several reasons: 1) On Earth, molecular phylogeny suggests that many of the most primitive organisms are hyperthermophiles, implying that life on this planet may have arisen in hydrothermal settings; 2) on Mars, similar settings would have supplied energy- and nutrient-rich waters in which early martian life may have evolved; 3) such regions on Mars would have constituted oases of continued habitability providing warm, liquid water to primitive life forms as the planet became colder and drier; and 4) mineralization associated with hydrothermal settings could have preserved biosignatures from those martian life forms. Accordingly, if life ever developed on Mars, then hydrothermal spring deposits would be excellent localities in which to search for morphological or chemical remnants of that life. Previous attempts to identify martian spring deposits from orbit have been general or limited by resolution of available data. However, new satellite imagery from HiRISE has a resolution of 28 cm/pixel which allows detailed analysis of geologic structure and geomorphology. Based on these new data, we report several features in Vernal Crater, Arabia Terra that we interpret as ancient hydrothermal springs.

  6. Sample Return from Ancient Hydrothermal Springs

    NASA Technical Reports Server (NTRS)

    Allen, Carlton C.; Oehler, Dorothy Z.

    2008-01-01

    Hydrothermal spring deposits on Mars would make excellent candidates for sample return. Molecular phylogeny suggests that that life on Earth may have arisen in hydrothermal settings [1-3], and on Mars, such settings not only would have supplied energy-rich waters in which martian life may have evolved [4-7] but also would have provided warm, liquid water to martian life forms as the climate became colder and drier [8]. Since silica, sulfates, and clays associated with hydrothermal settings are known to preserve geochemical and morphological remains of ancient terrestrial life [9-11], such settings on Mars might similarly preserve evidence of martian life. Finally, because formation of hydrothermal springs includes surface and subsurface processes, martian spring deposits would offer the potential to assess astrobiological potential and hydrological history in a variety of settings, including surface mineralized terraces, associated stream deposits, and subsurface environments where organic remains may have been well protected from oxidation. Previous attempts to identify martian spring deposits from orbit have been general or limited by resolution of available data [12-14]. However, new satellite imagery from HiRISE has a resolution of 28 cm/pixel, and based on these new data, we have interpreted several features in Vernal Crater, Arabia Terra as ancient hydrothermal springs [15, 16].

  7. Assessment of rescue opioid use in patients with post-bunionectomy pain treated with diclofenac potassium liquid-filled capsules.

    PubMed

    Willens, Joyce S; Bucior, Iwona; Bujanover, Shay; Mehta, Neel

    2015-01-01

    When used in multimodal analgesia for acute pain, nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the requirement for opioids during the perioperative period. To provide more insight into pain treatment during the outpatient period, we examined the use of opioid rescue medication (RM) and described the relationship between pain intensity and RM use in patients with acute pain after bunionectomy. Patients received placebo or 25 mg of a liquid-filled capsule version of the NSAID diclofenac potassium (DPLFC; n=188 patients/group) every 6 hours during the 48-hour inpatient period through the end of outpatient dosing on day 4. Opioid RM (hydrocodone/acetaminophen tablets, 5 mg/500 mg) was available as needed, but taken at least 1 hour post-study medication. Fewer patients taking DPLFC versus placebo requested opioid RM during the inpatient period (4.8%-44.7% versus 25.0%-90.4%) and also during the outpatient period (3.7%-16.0% versus 13.1%-46.4%). Moderate or severe pain after surgery (P=0.0307 and P=0.0002, respectively) or at second dose (P=0.0006 and P=0.0002, respectively) was predictive of RM use. Patients taking RM (placebo/DPLFC) reported more adverse events (RM 55.7%/40.6%; no RM 29.4%/26.0%). Most adverse events in the RM group were opioid-related. In summary, this study shows that DPLFC lowers the requirement for opioids, which is associated with a reduction in the occurrence of treatment side effects, while maintaining adequate analgesia for patients with moderate acute pain in both the outpatient and outpatient periods. Patients with more severe pain are more likely to use RM, but they still use fewer opioids when treated with DPLFC. This suggests that multimodal treatment using DPLFC and an opioid may offer an important clinical benefit in the treatment of acute pain, including in the home environment. PMID:25678812

  8. Enhanced heat transfer in partially-saturated hydrothermal systems

    SciTech Connect

    Bixler, N.E.; Carrigan, C.R.

    1986-01-01

    The role of capillarity is potentially important for determining heat transfer in hydrothermal regions. Capillarity allows mixing of phases in liquid/vapor systems and results in enhanced two-phase convection. Comparisons involving a numerical model with capillarity and analytical models without indicate that heat transfer can be enhanced by about an order of magnitude. Whether capillarity can be important for a particular hydrothermal region will depend on the nature of mineral precipitation as well as pore and fracture size distributions.

  9. Hydrothermal systems as environments for the emergence of life.

    PubMed

    Shock, E L

    1996-01-01

    Analysis of the chemical disequilibrium provided by the mixing of hydrothermal fluids and seawater in present-day systems indicates that organic synthesis from CO2 or carbonic acid is thermodynamically favoured in the conditions in which hyperthermophilic microorganisms are known to live. These organisms lower the Gibbs free energy of the chemical mixture by synthesizing many of the components of their cells. Primary productivity is enormous in hydrothermal systems because it depends only on catalysis of thermodynamically favourable, exergonic reactions. It follows that hydrothermal systems may be the most favourable environments for life on Earth. This fact makes hydrothermal systems logical candidates for the location of the emergence of life, a speculation that is supported by genetic evidence that modern hyperthermophilic organisms are closer to a common ancestor than any other forms of life. The presence of hydrothermal systems on the early Earth would correspond to the presence of liquid water. Evidence that hydrothermal systems existed early in the history of Mars raises the possibility that life may have emerged on Mars as well. Redox reactions between water and rock establish the potential for organic synthesis in and around hydrothermal systems. Therefore, the single most important parameter for modelling the geochemical emergence of life on the early Earth or Mars is the composition of the rock which hosts the hydrothermal system.

  10. Hydrothermal systems as environments for the emergence of life

    NASA Technical Reports Server (NTRS)

    Shock, E. L.

    1996-01-01

    Analysis of the chemical disequilibrium provided by the mixing of hydrothermal fluids and seawater in present-day systems indicates that organic synthesis from CO2 or carbonic acid is thermodynamically favoured in the conditions in which hyperthermophilic microorganisms are known to live. These organisms lower the Gibbs free energy of the chemical mixture by synthesizing many of the components of their cells. Primary productivity is enormous in hydrothermal systems because it depends only on catalysis of thermodynamically favourable, exergonic reactions. It follows that hydrothermal systems may be the most favourable environments for life on Earth. This fact makes hydrothermal systems logical candidates for the location of the emergence of life, a speculation that is supported by genetic evidence that modern hyperthermophilic organisms are closer to a common ancestor than any other forms of life. The presence of hydrothermal systems on the early Earth would correspond to the presence of liquid water. Evidence that hydrothermal systems existed early in the history of Mars raises the possibility that life may have emerged on Mars as well. Redox reactions between water and rock establish the potential for organic synthesis in and around hydrothermal systems. Therefore, the single most important parameter for modelling the geochemical emergence of life on the early Earth or Mars is the composition of the rock which hosts the hydrothermal system.

  11. Hydrothermal processing of new fly ash cement

    SciTech Connect

    Jiang, W.; Roy, D.M. )

    1992-04-01

    The recent Mount Pinatubo volcanic eruption in the Philippines, in which at least 268 people died, shows that volcanic eruptions can be highly destructive. The eruption shot ash and debris over the countryside; six towns near the volcano faced a high risk of devastating mudslides, and nearly 2000 U.S. service members and their families were evacuated from two nearby military bases. However, this paper reports that not all the consequences of volcanic eruptions are bad. Under hydrothermal conditions, volcanic ash can be transformed into zeolitic tuff and, eventually, into clay minerals that constitute agricultural soils. The Materials Research Laboratory (MRL) has recently used some artificial pozzolanas (fly ash) that when mixed with lime, under hydrothermal conditions, also produced a new type of cementitious material. This was categorized as a new fly ash cement. The formation of a new hydrothermally treated wood-fiber-reinforced composite has also been demonstrated. It is apparent, however, that with respect to concerns about detailed knowledge of the reactivity of calcium silicate-based materials under hydrothermal conditions, the application of the technology far outweighs the understanding of the underlying principles of reactivity. It would seem that an understanding of reactions on the molecular level is just beginning, and that work on hydrothermal reactions is still a potentially lucrative area of research.

  12. Hydrothermal carbonization and torrefaction of grape pomace: a comparative evaluation.

    PubMed

    Pala, Mehmet; Kantarli, Ismail Cem; Buyukisik, Hasan Baha; Yanik, Jale

    2014-06-01

    Grape pomace was treated by hydrothermal carbonization (sub-critical water, 175-275°C) and torrefaction (nitrogen atmosphere, 250 and 300°C), with mass yield of solid product (char) ranging between 47% and 78%, and energy densification ratio to 1.42-1.15 of the original feedstock. The chars were characterised with respect to their fuel properties, morphological and structural properties and combustion characteristics. The hydrothermal carbonization produced the char with greater energy density than torrefaction. The chars from torrefaction were found to be more aromatic in nature than that from hydrothermal carbonization. Hydrothermal carbonization process produced the char having high combustion reactivity. Most interesting was the finding that aqueous phase from hydrothermal carbonization had antioxidant activity. The results obtained in this study showed that HTC appears to be promising process for a winery waste having high moisture content.

  13. Study of structural modification of sugarcane bagasse employing hydrothermal treatment followed by atmospheric pressure plasmas treatment

    NASA Astrophysics Data System (ADS)

    Amorim, Jayr; Pimenta, Maria Teresa; Gurgel, Leandro; Squina, Fabio; Souza-Correa, Jorge; Curvelo, Antonio

    2009-10-01

    Nowadays, the cellulosic ethanol is an important alternative way to many liquid biofuels using renewable biomass rich in polysaccharides. To be used as feedstock for ethanol production, the bagasse needs to be pretreated in order to expose its main constitutive. The present work proposes the use of different pretreatment processes to better expose the cellulose for hydrolysis and fermentation. In the present paper the sugarcane bagasse was submitted to a hydrothermal pretreatment followed by atmospheric pressure plasmas (APPs). An RF microplasma torch was employed as APPs in Ar and Ar/O2 mixing. The bagasse was treated in discharge and post-discharge regions. The position and time of treatment was varied as well as the gas mixture. The quantity of polysaccharides was determined by using high performance liquid chromatography. It was observed the release of a fraction of the hemicelluloses in the sugarcane bagasse. Modifications in the surface of the sugarcane fibers were monitored by employing scanning electron microscopy.

  14. Dissolution of D2EHPA in liquid-liquid extraction process: implication on metal removal and organic content of the treated water.

    PubMed

    Lee, Po-Ching; Li, Chi-Wang; Chen, Jie-Yuan; Li, Ying-Sheng; Chen, Shiao-Shing

    2011-11-15

    Effects of pH, extractant/diluent ratios, and metal concentrations on the extent of extractant dissolution during liquid-liquid extraction were investigated. Experimental result shows that D(2)EHPA dissolution increases dramatically at pH above 4, leveling off at pH 6-7. The phenomenon is consistent with deprotonation of D(2)EHPA and the domination of negatively charged D(2)EHPA species at pH of higher than 4. Concentration of D(2)EHPA in the aqueous phase, i.e., the extent of extractant dissolution, drops after addition of metal and decreases with increasing metal concentration. The amount of D(2)EHPA 're-entering' the organic phase is calculated to be 2.04 mol per mol of Cd added, which is quite closed to the stoichiometric molar ratio of 2 between D(2)EHPA and Cd via ion exchange reaction. The effect of metal species on the extent of extractant/metal complexes re-entering is in the order of Cd ≈ Zn > Ag, which might be coincident to the complexation stability of these metals with D(2)EHPA. The extent of extractant dissolution in liquid-liquid extraction process depends on the type and concentration of metal to be removed, pH of aqueous phase, and extractant/diluent ratios. PMID:21937070

  15. Methods to enhance the characteristics of hydrothermally prepared slurry fuels

    SciTech Connect

    Anderson, Chris M.; Musich, Mark A.; Mann, Michael D.; DeWall, Raymond A.; Richter, John J.; Potas, Todd A.; Willson, Warrack G.

    2000-01-01

    Methods for enhancing the flow behavior and stability of hydrothermally treated slurry fuels. A mechanical high-shear dispersion and homogenization device is used to shear the slurry fuel. Other improvements include blending the carbonaceous material with a form of coal to reduce or eliminate the flocculation of the slurry, and maintaining the temperature of the hydrothermal treatment between approximately 300.degree. to 350.degree. C.

  16. Sensitive determination of estrogens in environmental waters treated with polymeric ionic liquid-based stir cake sorptive extraction and liquid chromatographic analysis.

    PubMed

    Chen, Lei; Mei, Meng; Huang, Xiaojia; Yuan, Dongxing

    2016-05-15

    A simple, sensitive and environmentally friendly method using polymeric ionic liquid-based stir cake sorptive extraction followed by high performance liquid chromatography with diode array detection (HPLC/DAD) has been developed for efficient quantification of six selected estrogens in environmental waters. To extract trace estrogens effectively, a poly (1-ally-3-vinylimidazolium chloride-co-ethylene dimethacrylate) monolithic cake was prepared and used as the sorbent of stir cake sorptive extraction (SCSE). The effects of preparation conditions of sorbent and extraction parameters of SCSE for estrogens were investigated and optimized. Under optimal conditions, the developed method showed satisfactory analytical performance for targeted analytes. Low limits of detection (S/N=3) and quantification limits (S/N=10) were achieved within the range of 0.024-0.057 µg/L and 0.08-0.19 µg/L, respectively. Good linearity of method was obtained for analytes with the correlation coefficients (R(2)) above 0.99. At the same time, satisfactory method repeatability and reproducibility was achieved in terms of intra- and inter-day precisions, respectively. Finally, the established SCSE-HPLC/DAD method was successfully applied for the determination of estrogens in different environmental water samples. Recoveries obtained for the determination of estrogens in spiked samples ranged from 71.2% to 108%, with RSDs below 10% in all cases.

  17. Quantitative determination of octylphenol, nonylphenol, alkylphenol ethoxylates and alcohol ethoxylates by pressurized liquid extraction and liquid chromatography-mass spectrometry in soils treated with sewage sludges.

    PubMed

    Andreu, Vicente; Ferrer, Emilia; Rubio, José Luís; Font, Guillermina; Picó, Yolanda

    2007-05-25

    Surfactants have one of the highest production rates of all organic chemicals. Non-ionic surfactants, especially alkylphenol ethoxylates, received most attention as precursors of estrogenic metabolic products generated during wastewater treatment. Alkylphenols (octyl and nonylphenol), alkylphenol polyethoxylates (APEOs), and alcohol ethoxylates (AEOs) have been determined in a Mediterranean forest soil (Mediterranean Rendzic Leptosol) amended with sludges from six waste water treatment plants (WWTPs) located in the Valencian Community. These compounds were isolated from soil by pressurized liquid extraction (PLE) using a mixture acetone-hexane (50:50 v/v), the extracts were cleaned up by solid-phase extraction (SPE) with C(18), and determined by liquid chromatography atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS) using analytical standards for quantification. The method enabled high-reliable identification by monitoring the corresponding ammonium adduct [M+NH(3)](+) for AEOs and APEOs, and the deprotonated molecule [M-H](-) for octyl and nonylphenol. Recoveries, determined spiking soil samples at different concentrations, ranged from 89 to 94%, with limits of quantification from 1 to 100 microg kg(-1). Data obtained from a soil sample mixed with biosolids in the laboratory showed that these compounds are present at concentrations ranging from 0.02 to 5 mg kg(-1). According to these concentrations, levels of possible risk can be concluded for the presence of non-ionic surfactants in soil. However, further assessment will be necessary to establish the relationship between exposure and effect findings. PMID:17306341

  18. The Lassen hydrothermal system

    USGS Publications Warehouse

    Ingebritsen, Steven E.; Bergfeld, Deborah; Clor, Laura; Evans, William C.

    2016-01-01

    The active Lassen hydrothermal system includes a central vapor-dominated zone or zones beneath the Lassen highlands underlain by ~240 °C high-chloride waters that discharge at lower elevations. It is the best-exposed and largest hydrothermal system in the Cascade Range, discharging 41 ± 10 kg/s of steam (~115 MW) and 23 ± 2 kg/s of high-chloride waters (~27 MW). The Lassen system accounts for a full 1/3 of the total high-temperature hydrothermal heat discharge in the U.S. Cascades (140/400 MW). Hydrothermal heat discharge of ~140 MW can be supported by crystallization and cooling of silicic magma at a rate of ~2400 km3/Ma, and the ongoing rates of heat and magmatic CO2 discharge are broadly consistent with a petrologic model for basalt-driven magmatic evolution. The clustering of observed seismicity at ~4–5 km depth may define zones of thermal cracking where the hydrothermal system mines heat from near-plastic rock. If so, the combined areal extent of the primary heat-transfer zones is ~5 km2, the average conductive heat flux over that area is >25 W/m2, and the conductive-boundary length <50 m. Observational records of hydrothermal discharge are likely too short to document long-term transients, whether they are intrinsic to the system or owe to various geologic events such as the eruption of Lassen Peak at 27 ka, deglaciation beginning ~18 ka, the eruptions of Chaos Crags at 1.1 ka, or the minor 1914–1917 eruption at the summit of Lassen Peak. However, there is a rich record of intermittent hydrothermal measurement over the past several decades and more-frequent measurement 2009–present. These data reveal sensitivity to climate and weather conditions, seasonal variability that owes to interaction with the shallow hydrologic system, and a transient 1.5- to twofold increase in high-chloride discharge in response to an earthquake swarm in mid-November 2014.

  19. Laser-driven microflow-induced bistable orientation of a nematic liquid crystal in perfluoropolymer-treated unrubbed cells.

    PubMed

    Jampani, V S R; Skarabot, M; Takezoe, H; Muševič, I; Dhara, S

    2013-01-14

    We demonstrate laser-driven microflow-induced orientational change (homeotropic to planar) in a dye-doped nematic liquid crystal. The homeotropic to planar director alignment is achieved in unrubbed cells in the thermal hysteresis range of a discontinuous anchoring reorientation transition due to the local heating by light absorption in dye-doped sample. Various bistable patterns were recorded in the cell by a programmable laser tweezers. The width of the patterns depend on the scanning speed of the tightly focussed laser beam and the minimum width obtained is approximately equal to 0.57μm which is about 35 times smaller than the earlier report in the rubbed cells. We show that the motion of the microbeam spot causes local flow as a result the liquid crystal director is aligned along that direction. PMID:23388965

  20. Concentration and form of copper released into aquatic systems from commercial liquid and micronized pressure treated lumber.

    EPA Science Inventory

    The fate and effects of pristine engineered metal nanomaterials (ENMs) in simplified systems have been widely studied; however, little is known about the potential release and impact of metal ENMs from consumer goods, especially lumber that has been treated with micronized copper...

  1. Concentration and form of copper released into aquatic systems from commercial liquid and micronized pressure treated lumber

    EPA Science Inventory

    The fate and effects of pristine engineered metal nanomaterials (ENMs) in simplified systems have been widely studied; however, little is known about the potential release and impact of metal ENMs from consumer goods, especially lumber which has been treated with micronized coppe...

  2. A randomized controlled trial to compare the effects of liquid versus powdered recombinant human growth hormone in treating patients with severe burns

    PubMed Central

    CHEN, GUOXIAN; SHAO, HUAWEI; PAN, XUANLIANG

    2016-01-01

    Recombinant human growth hormone (rhGH) promotes protein utilization and synthesis, and is widely used as a therapy to treat severe burns. The present randomized controlled trial evaluated the effects of different forms of rhGH on patients with severe burns. A total of 29 adult severe burns patients were enrolled between February 2009 and November 2011, and randomly assigned to either treatment group (T, liquid rhGH) or control group (C, powder rhGH). From days 5 to 7 following the infliction of burns, both patient groups received rhGH at 0.067 mg/kg/d, once for 10 days. Median serum pre-albumin levels increased in both groups following treatment, the elevation from baseline was significantly higher in the T group on day 10 compared to the C group (88 mg/l vs. 65 mg/l, P=0.046). C-reactive protein, fasting plasma glucose and body weight decreased in both groups. Body weight was significantly lower in the T compared to the C group at baseline, Day 5 and Day 10 (P=0.046, P=0.018 and P=0.006, respectively), however the decrease from baseline levels were not significantly different. Wound healing time was similar between groups (P=0.270). In conclusion the early use of liquid rather than powder rhGH may be more beneficial for treating adult patients with severe burns. PMID:27123246

  3. Experimental constraints on hydrothermal activities in Enceladus

    NASA Astrophysics Data System (ADS)

    Sekine, Y.; Shibuya, T.; Suzuki, K.; Kuwatani, T.

    2012-12-01

    C). This is because NH3 decomposition proceeds inefficiently due to efficient H2 production via serpentinization. Our experimental results also suggest that SiO2 concentration dissolved in hydrothermal fluids simulating Enceladus' condition would be buffered by the serpentine-brucite system. The presence of NH3 in the hydrothermal conditions keeps pH of the solution high (pH 9-11). We suggest that under such conditions, SiO2 concentrations in the fluids would be 0.1 mmol/L or less for temperature < 350°C. Given the SiO2 solubility of 1-10 mmol/L at 0°C and pH 9-11, direct formation of amorphous SiO2 would not occur in Enceladus' hydrothermal systems. To produce amorphous SiO2, large-scale hydrothermal activities and subsequent concentration of dissolved SiO2 in the ocean (due to freezing and/or evaporation of liquid water) would be required, which is consistent with high concentrations of radiogenic Ar and sodium salts in the plume [2, 6]. [1] Porco et al., Science 311, 1393 (2006). [2] Postberg et al., Nature 459, 1098 (2009). [3] Matson et al., Icarus 187, 569 (2007). [4] Hansen t al., Geophs. Res. Lett. 38, L11202 (2011). [5] Hsu et al., EOS Trans. AGU, (2010). [6] Waite et al., Nature 460, 487 (2009).

  4. Observation of hydrothermal flows with acoustic video camera

    NASA Astrophysics Data System (ADS)

    Mochizuki, M.; Asada, A.; Tamaki, K.; Scientific Team Of Yk09-13 Leg 1

    2010-12-01

    To evaluate hydrothermal discharging and its diffusion process along the ocean ridge is necessary for understanding balance of mass and flux in the ocean, ecosystem around hydrothermal fields and so on. However, it has been difficult for us to measure hydrothermal activities without disturbance caused by observation platform ( submersible, ROV, AUV ). We wanted to have some observational method to observe hydrothermal discharging behavior as it was. DIDSON (Dual-Frequency IDentification SONar) is acoustic lens-based sonar. It has sufficiently high resolution and rapid refresh rate that it can substitute for optical system in turbid or dark water where optical systems fail. DIDSON operates at two frequencies, 1.8MHz or 1.1MHz, and forms 96 beams spaced 0.3° apart or 48 beams spaced 0.6° apart respectively. It images out to 12m at 1.8MHz and 40m at 1.1MHz. The transmit and receive beams are formed with acoustic lenses with rectangular apertures and made of polymethylpentene plastic and FC-70 liquid. This physical beam forming allows DIDSON to consume only 30W of power. DIDSON updates its image between 20 to 1 frames/s depending on the operating frequency and the maximum range imaged. It communicates its host using Ethernet. Institute of Industrial Science, University of Tokyo ( IIS ) has understood DIDSON’s superior performance and tried to find new method for utilization of it. The observation systems that IIS has ever developed based on DIDSON are waterside surveillance system, automatic measurement system for fish length, automatic system for fish counting, diagnosis system for deterioration of underwater structure and so on. A next challenge is to develop an observation method based on DIDSON for hydrothermal discharging from seafloor vent. We expected DIDSON to reveal whole image of hydrothermal plume as well as detail inside the plume. In October 2009, we conducted seafloor reconnaissance using a manned deep-sea submersible Shinkai6500 in Central Indian

  5. CrystaSulf{sup SM} liquid redox and TDA gas phase H{sub 2}S conversion technologies for sour gas treating

    SciTech Connect

    Dalrymple, D.A.; Deberry, D.W.; Srinivas, G.

    1999-07-01

    Sour natural gas that contains hydrogen sulfide (H{sub 2}S) accounts for 15 to 25% of the gas processed in the US. Worldwide, as much as 30% of the gas reserves are sour. The need for more cost-effective approaches to process subquality gas is becoming more evident as new drilling occurs deeper within existing fields and in new fields. These types of producing zones tend to be sour. Gas containing very small amounts of sulfur (e.g., less than 0.2 long tons per day (LTPD)) can be cost-effectively treated with nonregenerable scavengers. This can be performed by injecting a liquid scavenger directly into a pipe containing the sour gas (direct injection) or by passing the sour gas through a tower containing a liquid or solid scavenger. Gas containing more than 25 to 30 LTPD of sulfur is generally processed by first separating the acid gases with an amine unit and then processing the amine offgas in a Claus plant to produce molten elemental sulfur. However, gas streams with sulfur amounts between 0.2 and 25 LTPD have generally posed treatment challenges to industry. This paper describes two emerging technologies for treating gases containing H{sub 2}S--the CrystaSulf{sup SM} liquid redox process and the TDA gas phase direct oxidation process. Both convert the H{sub 2}S to elemental sulfur and both are being pilot tested during 1999. Radian International is commercializing both processes. CrystaSulf appears to be well suited to treat sour streams containing between 0.2 and 25 LTPD of sulfur. CrystaSulf can achieve sulfur control efficiencies of 99.8% or greater and can be applied directly to sour streams or to tailgases from amine units or Clause plants. The TDA direct oxidation process provides a cost effective way to treat amine unit tailgas and in a single stage can achieve 85 to 97% sulfur control efficiencies for that stream. Following successful pilot plant testing, both processes will be available commercially.

  6. Hydrothermal reactivity of saponite.

    USGS Publications Warehouse

    Whitney, G.

    1983-01-01

    The nature and extent of the reactions of synthetic Fe-free saponite have been investigated under experimental hydrothermal conditions as a first step towards understanding saponite reactivity under relatively simple conditions. Saponite crystallizes from amorphous gel of ideal saponite composition within 7 days at 300o-550oC under P = 1 kbar. Reactions subsequent to this initial crystallization depend on reaction T and interlayer cations. Saponite is found to react hydrothermally, over a period of 200 days, at T down to 400oC, at least 150oC lower than previously reported, but showed no signs of reaction below 400oC. At 450oC, a mixture of talc/saponite and saponite/phlogopite clays forms from K-saponite via intracrystalline layer transformations, while above 450oC the initial K-saponite dissolves, with talc and phlogopite forming as discrete phases. After 200 days reactions at 400-450oC were not complete, so that given sufficient time to reach equilibrium, a lower hydrothermal stability limit for saponite is possible. Further study of the Fe-bearing saponite system will be required before experimental results can be applied to natural systems.-D.F.B.

  7. Using UCST Ionic Liquid as a Draw Solute in Forward Osmosis to Treat High-Salinity Water.

    PubMed

    Zhong, Yujiang; Feng, Xiaoshuang; Chen, Wei; Wang, Xinbo; Huang, Kuo-Wei; Gnanou, Yves; Lai, Zhiping

    2016-01-19

    The concept of using a thermoresponsive ionic liquid (IL) with an upper critical solution temperature (UCST) as a draw solute in forward osmosis (FO) was successfully demonstrated here experimentally. A 3.2 M solution of protonated betaine bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) was obtained by heating and maintaining the temperature above 56 °C. This solution successfully drew water from high-salinity water up to 3.0 M through FO. When the IL solution cooled to room temperature, it spontaneously separated into a water-rich phase and an IL-rich phase: the water-rich phase was the produced water that contained a low IL concentration, and the IL-rich phase could be used directly as the draw solution in the next cycle of the FO process. The thermal stability, thermal-responsive solubility, and UV-vis absorption spectra of the IL were also studied in detail.

  8. Using UCST Ionic Liquid as a Draw Solute in Forward Osmosis to Treat High-Salinity Water.

    PubMed

    Zhong, Yujiang; Feng, Xiaoshuang; Chen, Wei; Wang, Xinbo; Huang, Kuo-Wei; Gnanou, Yves; Lai, Zhiping

    2016-01-19

    The concept of using a thermoresponsive ionic liquid (IL) with an upper critical solution temperature (UCST) as a draw solute in forward osmosis (FO) was successfully demonstrated here experimentally. A 3.2 M solution of protonated betaine bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) was obtained by heating and maintaining the temperature above 56 °C. This solution successfully drew water from high-salinity water up to 3.0 M through FO. When the IL solution cooled to room temperature, it spontaneously separated into a water-rich phase and an IL-rich phase: the water-rich phase was the produced water that contained a low IL concentration, and the IL-rich phase could be used directly as the draw solution in the next cycle of the FO process. The thermal stability, thermal-responsive solubility, and UV-vis absorption spectra of the IL were also studied in detail. PMID:26649525

  9. CH₄ and N₂O emissions from different varieties of forage rice (Oryza sativa L.) treating liquid cattle waste.

    PubMed

    Riya, Shohei; Zhou, Sheng; Watanabe, Yoichi; Sagehashi, Masaki; Terada, Akihiko; Hosomi, Masaaki

    2012-03-01

    To evaluate global warming potential (GWP) on livestock waste treatment and biomass production in rice field, methane (CH(4)) and nitrous oxide (N(2)O) fluxes from forage rice fields planted with 4 different cultivars (Oryza sativa L. cv. Hamasari, Leafstar, Kusahonami and Takanari) were measured. Each of the cultivars were subjected either to basal fertilization alone (control plots) (84 kg N ha(-1)), or to basal fertilization plus topdressing with liquid cattle waste or LCW (treatment plots) (567 kg N ha(-1)). Liquid cattle waste application to the rice field resulted in peak CH(4) fluxes ranging from 22.0 to 32.1 mg m(-1)h(-1) during flooded conditions and large N(2)O fluxes ranging from 526 to 8591 μg m(-1)h(-1) after midsummer drainage and final drainage. The GWP of the control plots was between 1358 and 3872 kg CO(2)eq ha(-1), while the treatment plots ranged between 4503 and 8426 kg CO(2)eq ha(-1) and more than 60% of the GWP was from the N(2)O emission in treatment plots. In both the control and treatment plots, the lowest GWPs per ton of above-ground biomass were found to be from the Leafstar cultivar, which had a higher aboveground biomass than other cultivars; 117 kg CO(2)eq t(-1) from the control and 257 kg CO(2)eq t(-1) from the treatment plots. Thus, both forage production and suitable disposal of the LCW may be able to be achieved concomitantly with lower levels of GWP by cultivation of Leafstar in our field.

  10. Partial nitrification and nutrient removal in intermittently aerated sequencing batch reactors treating separated digestate liquid after anaerobic digestion of pig manure.

    PubMed

    Zhang, Mingchuan; Lawlor, Peadar G; Wu, Guangxue; Lynch, Brendan; Zhan, Xinmin

    2011-11-01

    The performance of an intermittently aerated sequencing batch reactor (IASBR) technology was investigated in achieving partial nitrification, organic matter removal and nitrogen removal from separated digestate liquid after anaerobic digestion of pig manure. The wastewater had chemical oxygen demand (COD) concentrations of 11,540 ± 860 mg/L, 5-day biochemical oxygen demand (BOD(5)) concentrations of 2,900 ± 200 mg/L and total nitrogen (TN) concentrations of 4,041 ± 59 mg/L, with low COD:N ratios (2.9) and BOD(5):COD ratios (0.25). Synthetic wastewater, simulating the separated digestate liquid with similar COD and nitrogen concentrations but BOD(5) of 11,500 ± 100 mg/L, was also treated using the IASBR technology. At a mean organic loading rate of 1.15 kg COD/(m(3) d) and a nitrogen loading rate of 0.38 kg N/(m(3) d), the COD removal efficiency was 89.8% in the IASBR (IASBR-1) treating digestate liquid and 99% in the IASBR (IASBR-2) treating synthetic wastewater. The IASBR-1 effluent COD was mainly due to inert organic matter and can be further reduced to less than 40 mg/L through coagulation. The partial nitrification efficiency of 71-79% was achieved in the two IASBRs and one cause for the stable long-term partial nitrification was the intermittent aeration strategy. Nitrogen removal efficiencies were 76.5 and 97% in IASBR-1 and IASBR-2, respectively. The high nitrogen removal efficiencies show that the IASBR technology is a promising technology for nitrogen removal from low COD:N ratio wastewaters. The nitrogen balance analysis shows that 59.4 and 74.3% of nitrogen removed was via heterotrophic denitrification in the non-aeration periods in IASBR-1 and IASBR-2, respectively.

  11. Proteomic mapping of bezafibrate-treated human hepatocytes in primary culture using two-dimensional liquid chromatography.

    PubMed

    Alvergnas, M; Rouleau, A; Lucchi, G; Heyd, B; Ducoroy, P; Richert, L; Martin, H

    2011-03-01

    Peroxisome proliferators have been extensively studied in rodents and are known to induce liver tumors, whereas the effects of these compounds are not very clearly identified in humans when they are widely exposed to herbicides, plasticizers, solvents or drugs such as the lipid-lowering fibrate bezafibrate (BEZA). We assessed the effect of BEZA on human hepatocyte proteome. Hepatocyte proteins, including those membrane-associated, were successfully extracted and separated using 2D-liquid chromatography (PF2D, Beckman coulter). Proteins that were regulated by ≥ 1.5 fold compared to controls were identified by mass spectrometry (MALDI-TOF, Bruker Daltonics) and SwissProt bank search. BEZA modified the expression of proteins involved in various metabolic pathways as well as in cell homeostasis. No marker of peroxisome proliferation was obtained but surprisingly the expression of proteins involved in liver carcinogenicity was modulated. The co-treatment of cultures with N-acetylcysteine modified the set of proteins regulated by BEZA, either by a potentiation or an inhibition of the effects. Our study points out that the hepatocellular redox environment has to be taken into account when using fibrates in therapeutics.

  12. Simultaneous Determination of Hormonal Residues in Treated Waters Using Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectrometry

    PubMed Central

    Guedes-Alonso, Rayco; Sosa-Ferrera, Zoraida; Santana-Rodríguez, José Juan

    2013-01-01

    In the last years, hormone consumption has increased exponentially. Because of that, hormone compounds are considered emerging pollutants since several studies have determinted their presence in water influents and effluents of wastewater treatment plants (WWTPs). In this study, a quantitative method for the simultaneous determination of oestrogens (estrone, 17β-estradiol, estriol, 17α-ethinylestradiol, and diethylstilbestrol), androgens (testosterone), and progestogens (norgestrel and megestrol acetate) has been developed to determine these compounds in wastewater samples. Due to the very low concentrations of target compounds in the environment, a solid phase extraction procedure has been optimized and developed to extract and preconcentrate the analytes. Determination and quantification were performed by ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The method developed presents satisfactory limits of detection (between 0.15 and 9.35 ng·L−1), good recoveries (between 73 and 90% for the most of compounds), and low relative standard deviations (under 8.4%). Samples from influents and effluents of two wastewater treatment plants of Gran Canaria (Spain) were analyzed using the proposed method, finding several hormones with concentrations ranged from 5 to 300 ng·L−1. PMID:23533966

  13. Hydrothermal carbonization of industrial mixed sludge from a pulp and paper mill.

    PubMed

    Mäkelä, Mikko; Benavente, Verónica; Fullana, Andrés

    2016-01-01

    Mixed sludge from a pulp and paper mill was hydrothermally carbonized at 180-260°C for 0.5-5h with the use of HCl or NaOH for determining the effect of acid and base additions during sludge carbonization. Based on the results carbonization was mainly governed by dehydration, depolymerization and decarboxylation of sludge components. Additive type had a statistically significant effect on hydrochar carbon content and carbon and energy yield, of which especially energy yield increased through the use of HCl. The theoretical energy efficiencies of carbonization increased with decreasing reaction temperature, retention time and the use of HCl and suggested that the energy requirement could be covered by the energy content of attained hydrochar. The BOD5/COD-ratios of analyzed liquid samples indicated that the dissolved organic components could be treated by conventional biological methods.

  14. Enceladus: Starting Hydrothermal Activity

    NASA Technical Reports Server (NTRS)

    Matson, D. L.; Castillo-Rogez, J. C.; Johnson, T. V.; Lunine, J. I.; Davies, A. G.

    2011-01-01

    We describe a process for starting the hydrothermal activity in Enceladus' South Polar Region. The process takes advantage of fissures that reach the water table, about 1 kilometer below the surface. Filling these fissures with fresh ocean water initiates a flow of water up from an ocean that can be self-sustaining. In this hypothesis the heat to sustain the thermal anomalies and the plumes comes from a slightly warm ocean at depth. The heat is brought to the surface by water that circulates up, through the crust and then returns to the ocean.

  15. Cody hydrothermal system

    SciTech Connect

    Heasler, H.P.

    1982-01-01

    The hot springs of Colter's Hell are the surface manifestations of a much larger hydothermal system. That system has been studied to define its extent, maximum temperature, and mechanism of operation. The study area covers 2700 km/sup 2/ (1040 mi/sup 2/) in northwest Wyoming. Research and field work included locating and sampling the hot springs, geologic mapping, thermal logging of available wells, measuring thermal conductivities, analyzing over 200 oil and gas well bottom-hole temperatures, and compiling and analyzing hydrologic data. These data were used to generate a model for the hydrothermal system.

  16. Hydrothermal reaction of fly ash. Final report

    SciTech Connect

    Brown, P.W.

    1994-12-31

    The reactions which occur when fly ash is treated under hydrothermal conditions were investigated. This was done for the following primary reasons. The first of these is to determine the nature of the phases that form to assess the stabilities of these phases in the ambient environment and, finally, to assess whether these phases are capable of sequestering hazardous species. The second reason for undertaking this study was whether, depending on the composition of the ash and the presence of selected additives, it would be possible under hydrothermal conditions to form compounds which have cementitious properties. Formation of four classes of compounds, which bracket likely fly ash compositional ranges, were selected for study. The classes are calcium silicate hydrates, calcium selenates, and calcium aluminosulfates, and silicate-based glasses. Specific compounds synthesized were determined and their stability regions assessed. As part of stability assessment, the extent to which selected hazardous species are sequestered was determined. Finally, the cementing properties of these compounds were established. The results obtained in this program have demonstrated that mild hydrothermal conditions can be employed to improve the reactivity of fly ash. Such improvements in reactivity can result in the formation of monolithic forms which may exhibit suitable mechanical properties for selected applications as building materials. If the ashes involved are considered hazardous, the mechanical properties exhibited indicated the forms could be handled in a manner which facilitates their disposal.

  17. Delisting petition for 300-M saltstone (treated F006 sludge) from the 300-M liquid effluent treatment facility

    SciTech Connect

    Not Available

    1989-04-04

    This petition seeks exclusion for stabilized and solidified sludge material generated by treatment of wastewater from the 300-M aluminum forming and metal finishing processes. The waste contains both hazardous and radioactive components and is classified as a mixed waste. The objective of this petition is to demonstrate that the stabilized sludge material (saltstone), when properly disposed, will not exceed the health-based standards for the hazardous constituents. This petition contains sampling and analytical data which justify the request for exclusion. The results show that when the data are applied to the EPA Vertical and Horizontal Spread (VHS) Model, health-based standards for all hazardous waste constituents will not be exceeded during worst case operating and environmental conditions. Disposal of the stabilized sludge material in concrete vaults will meet the requirements pertaining to Waste Management Activities for Groundwater Protection at the Savannah River Site in Aiken, S.C. Documents set forth performance objectives and disposal options for low-level radioactive waste disposal. Concrete vaults specified for disposal of 300-M saltstone (treated F006 sludge) assure that these performance objectives will be met.

  18. The fate of lignin during hydrothermal pretreatment

    PubMed Central

    2013-01-01

    Background Effective enzymatic hydrolysis of lignocellulosic biomass benefits from lignin removal, relocation, and/or modification during hydrothermal pretreatment. Phase transition, depolymerization/repolymerization, and solubility effects may all influence these lignin changes. To better understand how lignin is altered, Populus trichocarpa x P. deltoides wood samples and cellulolytic enzyme lignin (CEL) isolated from P. trichocarpa x P. deltoides were subjected to batch and flowthrough pretreatments. The residual solids and liquid hydrolysate were characterized by gel permeation chromatography, heteronuclear single quantum coherence NMR, compositional analysis, and gas chromatography–mass spectrometry. Results Changes in the structure of the solids recovered after the pretreatment of CEL and the production of aromatic monomers point strongly to depolymerization and condensation being primary mechanisms for lignin extraction and redeposition. The differences in lignin removal and phenolic compound production from native P. trichocarpa x P. deltoides and CEL suggested that lignin-carbohydrate interactions increased lignin extraction and the extractability of syringyl groups relative to guaiacyl groups. Conclusions These insights into delignification during hydrothermal pretreatment point to desirable pretreatment strategies and plant modifications. Because depolymerization followed by repolymerization appears to be the dominant mode of lignin modification, limiting the residence time of depolymerized lignin moieties in the bulk liquid phase should reduce lignin content in pretreated biomass. In addition, the increase in lignin removal in the presence of polysaccharides suggests that increasing lignin-carbohydrate cross-links in biomass would increase delignification during pretreatment. PMID:23902789

  19. Hydrothermal Mineralization Along the Volcanically Active Mariana Arc

    NASA Astrophysics Data System (ADS)

    de Ronde, C. E.; Hein, J. R.; Embley, R. W.; Stern, R. J.

    2004-12-01

    In March and April, 2004, ROPOS ROV dives took place from the R/V T.G. Thompson along the volcanically active Mariana arc to ground truth CTD data collected a year earlier that indicated hydrothermal activity. Dives took place on seven volcanoes, six of which showed hydrothermal activity. We present data on samples collected from NW Rota-1 (14° , 36'N, 144° , 46'E), E. Diamante (15° , 56'N, 145° , 41'E), and NW Eifuku (21° , 29'N, 144° , 03'E), the three sites most studied. All the hydrothermal systems found are associated with volcano summits, or with resurgent domes inside a caldera. Brimstone vent at NW Rota-1 provided a dramatic display of thick, bellowing, yellow plumes that contained ash and molten sulfur. This site occurs at 500 m water depth and clearly shows closely associated magmatic-hydrothermal discharge. Sulfur was the dominant hydrothermal mineral deposited around the vent and occurs as spheres in the surrounding volcaniclastic sediment, fracture fill and veins, and massive deposits. The Black Forest vent field at E Diamante consists of a sulfide-sulfate chimney system developed at about 650 m water depth. This is the only mature system discovered and consists of numerous tall (up to 9 m) chimneys. The measured fluid temperature of 240° C produces boiling at the depth of the vents. The chimneys and mounds are composed of varying amounts of pyrite, sphalerite, chalcopyrite, barite, and anhydrite. Hydrothermal Mn oxides occur on the surface of inactive chimneys. This mineralogy contrasts with the other two systems, which deposit sulfur as the dominant hydrothermal product. The Cu-Zn-Fe-Ba mineralization is perhaps largely controlled by water/rock interaction. A unique hydrothermal field (Champagne field) was found at NW Eifuku where liquid CO2 is discharging from focused- and diffuse-flow vents at 1600 m water depth. The focused-flow vents consist of small chimneys and mounds up to a meter high that are composed of sulfur and yet to be

  20. A multidimensional model of direct-stream heating of newspaper and municipal solid waste in a hydrothermal reactor

    SciTech Connect

    Thorsness, C.B.

    1995-09-28

    Hydrothermal treatment (reaction in a water medium at elevated temperatures) can transform many municipal solid waste (MSW) constituents into a synthetic coal material which is more amenable for use as a fuel or chemical feedstock than the raw MSW. One means of heating the MSW is to use direct high temperature steam injection into a closed reactor and allow the latent heat of the steam to raise the MSW to the desired temperature and at the same time build the pressure necessary to maintain a water phase. This report describes a computer model which can be used to look at details of the steam flow, water evaporation/condensation, thermal evolution, and MSW decomposition in a direct-steam heated MSW hydrothermal reactor. The model treats the system as a packed bed using a Darcy`s law formulation for computing gas flow rates. The model has been applied to a pilot and a commercial scale system. Computations take between 1-6 hours on a HP-9000/730. Initial computations performed with the model indicate that pressure drop and velocities on a pilot scale systems will be small. On the other hand, they indicate that gas velocities inside a commercial scale reactor can reach levels at which entrainment of liquid or solids could occur. In addition, on the commercial scale, model results indicate that in the absence of liquid water flow the thermal coupling between vessel contents and heavy reactor walls should be small thus minimizing unwanted heat loss.

  1. Delayed mouth-caecum transit of a lactulose labelled liquid test meal in patients with steatorrhoea caused by partially treated coeliac disease.

    PubMed Central

    Spiller, R C; Lee, Y C; Edge, C; Ralphs, D N; Stewart, J S; Bloom, S R; Silk, D B

    1987-01-01

    Mouth-caecum transit time (M-CTT) of a lactulose labelled liquid test meal has been measured in 27 coeliac patients and 10 healthy controls using the breath hydrogen technique. Although all patients were urged to maintain a gluten free diet, not all did, and there was, therefore, a wide range in the severity of fat malabsorption within the patient group. Gastric emptying of a 113Indium DTPA-labelled liquid test meal was also assessed in separate studies on six healthy controls and 11 of the coeliac patients. Fasting breath hydrogen concentrations and the response to lactulose, as assessed both by the rate of rise, and the peak breath hydrogen concentration reached, showed no difference between coeliacs and controls, regardless of the presence or absence of steatorrhoea. Mouth-caecum transit time in the 16 coeliac patients with steatorrhea (faecal fat greater than 7 g/24 h) was, however, significantly prolonged being 158 +/- 18 minutes (mean +/- SEM), compared with 70 +/- 9 minutes for the controls (p less than 0.02), and 83 +/- 15 minutes for the 11 coeliacs without steatorrhoea (p less than 0.002). Mouth-caecum transit time in the coeliac patients was linearly related to the 24 hour faecal fat excretion, r = 0.55, n = 27, p less than 0.01. Slow mouth-caecum transit in the coeliacs with steatorrhoea was not caused by delayed gastric emptying as the t1/2 for coeliacs with steatorrhoea was within the normal range. Coeliacs with delayed mouth-caecum transit had impaired insulin release but the postprandial profiles of the other peptides measured (cholecystokinin, GIP, secretin, motilin, neurotensin, enteroglucagon, and peptide YY) were all within the normal range in this group of partially treated coeliac patients. PMID:3678957

  2. Time Variation of Fluid Chemistry at Iheya North Seafloor Hydrothermal System, mid-Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Chiba, H.; Ishibashi, J.; Kataoka, S.; Umeki, Y.; Kouzuma, F.; Nakayama, N.; Tsunogai, U.

    2002-12-01

    hydrothermal fluid was clogged by chemical precipitates, the steam phase, more mobile than the liquid phase, may become preferentially emitted in the peripheral area. This may explain the change in salinities of vent fluid observed in this hydrothermal system.

  3. Exploration strategies for hydrothermal deposits.

    PubMed

    Horn, R A

    1996-01-01

    With unlimited money the most certain strategy for finding most hydrothermal metal deposits would be by drilling to 5000 m at 50 m spacing. However, the cost would far outweigh the benefit of the discoveries. Geological knowledge and exploration techniques may be used to obtain the greatest benefit for minimum cost, and to concentrate human and material resources in the most economic way in areas with the highest probability of discovery. This paper reviews the economic theory of exploration based on expected value, and the application of geological concepts and exploration techniques to exploration for hydrothermal deposits. Exploration techniques for hydrothermal-systems on Mars would include geochemistry and particularly passive geophysical methods.

  4. Hydrothermal processes at seafloor spreading centers,

    SciTech Connect

    Sleep, N.H.

    1983-01-01

    This chapter discusses the initial entry of hydrothermal seawater into deep levels of the oceanic crust, the effectiveness of hydrothermal circulation in cooling the crust, the geometry of hydrothermal circulation, the relationship between the hydrothermal circulation and the magma chamber, the reaction of the oceanic crust with the seawater, and the identification of the hydrothermal fluid which alters a rock sample. Topics considered include the crack front, observation relevant to the crack front, the limitations of the crack front hypothesis, the observed pattern of hydrothermal alteration, the nature of the hydrothermal fluid, the physics of large scale convection, and convection through crack zones. Knowledge of hydrothermal circulation at the ridge axis is based on sampling of the hydrothermal fluid, indirect geophysical measurements of the oceanic crust, and studies of rocks which are believed to have undergone hydrothermal alteration at the ridge axis. Includes 2 drawings.

  5. Emission of CO2 from seafioor hydrothermal systems at Mariana Trough

    NASA Astrophysics Data System (ADS)

    Maeda, Y.; Shitashima, K.

    2007-12-01

    Hydrothermal vent fluids are highly enriched in CO2 and the CO2 rich fluids are released into the ocean as a hydrothermal plume. Especially, the emission of hydrothermal-related liquid CO2 from the seafloor (about 1500m) was discovered at the Okinawa Trough and Mariana Trough. At these areas, it is considered that the liquid CO2 rises up to shallow depth as a CO2 droplet and that the rising CO2 droplet dissolves gradually in ambient seawater. The observation of the hydrothermal-related CO2 would provide the opportunity for understanding the physic-chemical behavior and diffusion process of liquid CO2 in the ocean. Newly developed in-situ pH/pCO2 sensor can detect precisely and rapidly the changes of pH and pCO2 derived from high CO2 concentration. At southern Mariana Trough, the pH/pCO2 sensor was installed onto the manned submersible and in-situ pH and pCO2 data were measured every 10 seconds during the operation on the hydrothermal active site. Mapping survey of low pH and pCO2 distribution was performed on the hydrothermal active site by the grid navigation of the manned submersible that installed the pH/pCO2 sensor. The results of pH mapping survey showed only localized pH depression at the hydrothermal active site. At NW Eifuku submarine volcano, hydrothermal-related liquid CO2 dispersion was observed by using a towing multi-layer monitoring system. This system can observe the dispersion behavior of CO2 by towing several in-situ pH/pCO2 sensors and SSBL transponders in the high CO2 plume. Low pH plume of 100m high and 200m wide was detected above the summit of NW Eifuku submarine volcano.

  6. Distribution of buried hydrothermal alteration deduced from high-resolution magnetic surveys in Yellowstone National Park

    NASA Astrophysics Data System (ADS)

    Bouligand, Claire; Glen, Jonathan M. G.; Blakely, Richard J.

    2014-04-01

    Yellowstone National Park (YNP) displays numerous and extensive hydrothermal features. Although hydrothermal alteration in YNP has been extensively studied, the volume, geometry, and type of rock alteration at depth remain poorly constrained. In this study, we use high-resolution airborne and ground magnetic surveys and measurements of remanent and induced magnetization of field and drill core samples to provide constraints on the geometry of hydrothermal alteration within the subsurface of three thermal areas in YNP (Firehole River, Smoke Jumper Hot Springs, and Norris Geyser Basin). We observe that hydrothermal zones from both liquid- and vapor-dominated systems coincide with magnetic lows observed in aeromagnetic surveys and with a decrease of the amplitude of short-wavelength anomalies seen in ground magnetic surveys. This suggests a strong demagnetization of both the shallow and deep substratum within these areas associated with the removal of magnetic minerals by hydrothermal alteration processes. Such demagnetization is confirmed by measurements of rock samples from hydrothermal areas which display significantly decreased total magnetization. A pronounced negative anomaly is observed over the Lone Star Geyser and suggests a significant demagnetization of the substratum associated with areas displaying large-scale fluid flow. The ground and airborne magnetic surveys are used to evaluate the distribution of magnetization in the subsurface. This study shows that significant demagnetization occurs over a thickness of at least a few hundred meters in hydrothermal areas at YNP and that the maximum degree or maximum thickness of demagnetization correlates closely with the location of hydrothermal activity and mapped alteration.

  7. Hydrothermal Chemotrophic Biosignatures on Mars

    NASA Astrophysics Data System (ADS)

    Westall, F.; Campbell, K. A.; Gautret, P.; Bréhéret, J.; Foucher, F.; Vago, J.; Kminek, G.; Hubert, A.; Hickman-Lewis, K.; Cockell, C. S.

    2016-05-01

    Hydrothermal chemotrophic biosignatures (morphological and geo-organochemical) were common in shallow water on the anaerobic early Earth, preserved by silicification. They are representative also of shallow crustal biosignatures.

  8. High organic loading rate on thermophilic hydrogen production and metagenomic study at an anaerobic packed-bed reactor treating a residual liquid stream of a Brazilian biorefinery.

    PubMed

    Ferraz Júnior, Antônio Djalma Nunes; Etchebehere, Claudia; Zaiat, Marcelo

    2015-06-01

    This study evaluated the influence of a high organic loading rate (OLR) on thermophilic hydrogen production at an up-flow anaerobic packed-bed reactor (APBR) treating a residual liquid stream of a Brazilian biorefinery. The APBR, filled with low-density polyethylene, was operated at an OLR of 84.2 kg-COD m(-3) d(-1). This value was determined in a previous study. The maximum values of hydrogen production and yield were 5,252.6 mL-H2 d(-1) and 3.7 mol-H2 mol(-1)(total carbohydrates), respectively. However, whereas the OLR remained constant, the specific organic load rate (sOLR) decreased throughout operation from 1.38 to 0.72 g-Total carbohydratesg-VS(-1) h(-1), this decrease negatively affected hydrogen production. A sOLR of 0.98 g-Total carbohydratesg-VS(-1) h(-1) was optimal for hydrogen production. The microbial community was studied using 454-pyrosequencing analysis. Organisms belonging to the genera Caloramator, Clostridium, Megasphaera, Oxobacter, Thermoanaerobacterium, and Thermohydrogenium were detected in samples taken from the reactor at operation days 30 and 60, suggesting that these organisms contribute to hydrogen production. PMID:25812810

  9. High organic loading rate on thermophilic hydrogen production and metagenomic study at an anaerobic packed-bed reactor treating a residual liquid stream of a Brazilian biorefinery.

    PubMed

    Ferraz Júnior, Antônio Djalma Nunes; Etchebehere, Claudia; Zaiat, Marcelo

    2015-06-01

    This study evaluated the influence of a high organic loading rate (OLR) on thermophilic hydrogen production at an up-flow anaerobic packed-bed reactor (APBR) treating a residual liquid stream of a Brazilian biorefinery. The APBR, filled with low-density polyethylene, was operated at an OLR of 84.2 kg-COD m(-3) d(-1). This value was determined in a previous study. The maximum values of hydrogen production and yield were 5,252.6 mL-H2 d(-1) and 3.7 mol-H2 mol(-1)(total carbohydrates), respectively. However, whereas the OLR remained constant, the specific organic load rate (sOLR) decreased throughout operation from 1.38 to 0.72 g-Total carbohydratesg-VS(-1) h(-1), this decrease negatively affected hydrogen production. A sOLR of 0.98 g-Total carbohydratesg-VS(-1) h(-1) was optimal for hydrogen production. The microbial community was studied using 454-pyrosequencing analysis. Organisms belonging to the genera Caloramator, Clostridium, Megasphaera, Oxobacter, Thermoanaerobacterium, and Thermohydrogenium were detected in samples taken from the reactor at operation days 30 and 60, suggesting that these organisms contribute to hydrogen production.

  10. Hydrothermal Growth of Polyscale Crystals

    NASA Astrophysics Data System (ADS)

    Byrappa, Kullaiah

    In this chapter, the importance of the hydrothermal technique for growth of polyscale crystals is discussed with reference to its efficiency in synthesizing high-quality crystals of various sizes for modern technological applications. The historical development of the hydrothermal technique is briefly discussed, to show its evolution over time. Also some of the important types of apparatus used in routine hydrothermal research, including the continuous production of nanosize crystals, are discussed. The latest trends in the hydrothermal growth of crystals, such as thermodynamic modeling and understanding of the solution chemistry, are elucidated with appropriate examples. The growth of some selected bulk, fine, and nanosized crystals of current technological significance, such as quartz, aluminum and gallium berlinites, calcite, gemstones, rare-earth vanadates, electroceramic titanates, and carbon polymorphs, is discussed in detail. Future trends in the hydrothermal technique, required to meet the challenges of fast-growing demand for materials in various technological fields, are described. At the end of this chapter, an Appendix 18.A containing a more or less complete list of the characteristic families of crystals synthesized by the hydrothermal technique is given with the solvent and pressure-temperature (PT) conditions used in their synthesis.

  11. Geochemistry of hydrothermal fluids at the Hatoma Knoll in Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Toki, T.; Shinjo, R.; Ishibashi, J.; Tsunogai, U.; Sano, Y.; Takahata, N.; Yamanaka, T.; Kawagucci, S.; Ueno, Y.; Nunoura, T.; Takai, K.

    2012-12-01

    Hatoma knoll is a caldera volcano which exists in the southern part of Okinawa Trough, and the hydrothermal field was discovered in the caldera in 1999. A lava dome exists in the center part of the caldera, and clear smokers up to 324.5°C, benthic organism colony and liquid CO2, and CO2 hydrate have been observed around the dome. Since 2000, the investigation cruise (NT00-06, YK07-04, NT07-12, NT08-13, and NT09-10) by "Shinkai2000", "Shinkai6500" and the "HYPER-DOLPHIN 3K" has been carried out. Hydrothermal fluid samples were taken from the hydrothermal system, and chemical and isotopic compositions of the hydrothermal fluid samples were investigated. The chemical composition of hydrothermal fluid has high pH compared with the hydrothermal fluid in the mid-ocean ridge, and ammonium concentration is high, suggesting that the sediments covered the Okinawa Trough contribute to the chemical composition of hydrothermal fluid. The end-members of hydrothermal fluid show a variation, but the ratios of the end-members are consistent with each other, suggesting that the hydrothermal system has a single source and subcritical phase separation occurs below the seafloor. The equilibrium temperature with the quartz based on Si concentration was 350-400°C at 1-2 km below the seafloor. CO2 concentration in hydrothermal fluid showed the high-level value in the hydrothermal system in the world. The origin of the abundant CO2 is the carbonate on the subducting plate and the sediment in the Okinawa Trough based on the carbon isotope and the helium isotope. Methane is also the high-level concentration in the hydrothermal system in the world. Most of methane is generated through methanogenesis based on the carbon isotope ratio. Sr isotopic ratio in the hydrothermal fluid suggests the influence of sediment. However, the knoll surface was covered by rhyolite, the influence of sediment would occur in the recharge zone of the hydrothermal system. The methane would be microbially produced

  12. Thermal Effects on Hydrothermal Biomass Liquefaction

    NASA Astrophysics Data System (ADS)

    Zhang, Bo; von Keitz, Marc; Valentas, Kenneth

    Batch pressure vessels commonly used for hydrothermal liquefaction have typical heating times in the range of 30 to 60 min. Thermodynamically, the complex set of reactions are path dependent, so that the heating rate can possibly affect yields and the composition of the resultant liquid products. It is postulated that the mode of heat transfer becomes an uncontrolled variable in kinetic studies and can seriously impact scale-up. To confirm this hypothesis and minimize these heat-transfer-related artifacts, we designed a batch pressure vessel equipped with an induction heating system, which allows the reduction of heat-up times by about two orders of magnitude to several seconds, compared to tens of minutes with standard pressure reactors. This system was used to study the direct liquefaction of corn stover and aspen wood with a pretreatment. The heating rate was found to have no significant effect on the composition of the liquid products. However, the liquid yields are dependent on the heating rate. Varying the cooling rate does not show obvious effects. The results confirm that the heating rate, as governed by the mode of heat transfer, is an important factor that needs to be considered during scale-up.

  13. Subsurface Controls on Habitability of Hydrothermal Waters

    NASA Astrophysics Data System (ADS)

    Fristad, K. E.; Som, S. M.; Hoehler, T. M.

    2014-12-01

    Liquid water alone does not make an environment habitable. Environmental settings dominated by water-rock reactions such as in hydrothermal vents and springs are natural targets for astrobiological investigation of waterworlds because the rich geochemical diversity at these locales provides abundant energy in solvent to support microbial life. Hydrogen oxidizers are of particular interest because H2-based metabolisms are widespread and deeply rooted throughout the phylogenetic tree of life, implying they may have emerged extremely early in the evolution, and possibly even the origin, of life on Earth and potentially any other rocky bodies bearing liquid water. Dihydrogen (H2) can be lithogenically produced by the hydrolytic oxidation of the ferrous iron component in Fe-bearing minerals as well as by radiolytic cleavage of water by α, β, or γ radiation produced during the decay of radioactive isotopes. Lithogenic H2 production mechanisms operate across a range of rock types, but the concentration of dissolved H2 available to life is controlled by a number of subsurface factors such as surface geometry, water to rock ratio, production rate, and fluid flux. These factors are often controlled by the larger geologic and structural context of a particular site. We present results of an ongoing project that surveys H2 concentrations from terrestrial hydrothermal waters in diverse chemical and physical settings. Aqueous H2 concentrations and potential subsurface controls are presented for sites across the western U.S. including Yellowstone National Park, Lassen Volcanic National Park, and Iceland. In coordination with field data, we also investigate the habitability of various sites numerically by coupling a geochemical model of water-rock interaction with that of single-cell methanogenesis and compute a habitability index for the given environment. In particular, we investigate the control that temperature, rock composition, water composition, and water to rock ratio

  14. Evaluation of performance and microbial ecology of sequencing batch reactor and membrane bioreactor treating thin-film transistor liquid crystal display wastewater.

    PubMed

    Wu, Y J; Whang, L M; Huang, S J; Yang, Y F; Lei, C N; Cheng, S S

    2008-01-01

    In Taiwan, a substantial amount of thin-film transistor liquid crystal display (TFT-LCD) wastewater is produced daily due to an increasing production of the opto-electronic industry in recent years. The main components of TFT-LCD wastewater include dimethyl sulphoxide (DMSO), monoethanolamine (MEA), and tetra-methyl ammonium hydroxide (TMAH), which are recognized as non-or slow-biodegradable organic compounds and limited information is available regarding their biological treatablility. This study was conducted to evaluate the long-term performance of two bioreactors, anaerobic-aerobic (A/O) sequencing batch reactor (SBR) and aerobic membrane bioreactor (MBR), treating synthetic TFT-LCD wastewater containing DMSO, MEA, and TMAH with different loadings. For the A/O SBR, the influent wastewater was composed of 800 mg MEA/L, 430 mg DMSO/L, and 90 mg TMAH/L, respectively. After reaching steady-state, SBR was able to achieve more than 99% degradation efficiencies for the three compounds examined. For the case of aerobic MBR, the influent wastewater was composed of 550 mg MEA/L, 270 mg DMSO/L, and 330 mg TMAH/L, respectively, and degradation efficiencies for the three compounds achieved more than 99%. Although both different reactors shared similar and satisfactory degradation efficiencies for DMSO, MEA, and TMAH, the microbial ecology of these two reactors, as elucidated with molecular methods, was apparently different. The 16S rDNA-based cloning/sequencing results indicated that the dominant sequences retrieved from the aerobic MBR, including Hyphomicrobium denitrificans, Hyphomicrobium zavarzinii, Rhodobacter sp., and Methyloversatilis universalis, showed a clear linkage to their physiological properties of DMSO and TMAH degradation. On the other hand, Zoogloea sp., Chlorobium chlorochromatii, Agricultural soil bacterium, and Flavosolibacter ginsengiterrae were proliferated in the A/O SBR Run1, while Thiobacillus sp., Nitrosomonas sp., Thauera aromatica and Azoarcus

  15. Hydrothermal processing of BaTiO{sub 3}/polymer films

    SciTech Connect

    Slamovich, E.B.; Aksay, I.A.

    1994-12-31

    Hydrothermally derived films of BaTiO{sub 3} were fabricated by reacting thin layers of titanium organometallic liquid precursors in aqueous solutions containing Ba(OH){sub 2} and having a high pH. Cubic submicron polycrystalline films of BaTiO{sub 3} (thickness {approx} 1 {mu}m) were formed at 70 C. Low concentrations of block copolymers of polybutadiene and polystyrene were incorporated into the liquid precursor to prevent precursor film cracking. Higher polymer concentrations allowed fabrication of polymer/ceramic composite films by virtue of the low temperature used in hydrothermal processing.

  16. Reduction and structural evolution of graphene oxide sheets under hydrothermal treatment

    NASA Astrophysics Data System (ADS)

    Niu, Yongan; Fang, Qinghong; Zhang, Xin; Zhang, Panpan; Li, Yao

    2016-09-01

    This work carefully investigated the hydrothermal reduction of graphene oxide (GO) sheets. To evaluate the reduced extent, the as-prepared GO and RGO sheets in different conditions were measured by FT-IR, UV-Vis, Raman spectra and TEM morphologies. It revealed that the hydrothermal reduction of GO sheets was undergone four steps and the optimal condition was treated at 180 °C for 24 h. These RGO sheets exhibited the expectant morphologies and maintained the original sizes.

  17. Hydrothermal synthesis of ammonium illite

    USGS Publications Warehouse

    Sucha, V.; Elsass, F.; Eberl, D.D.; Kuchta, L'.; Madejova, J.; Gates, W.P.; Komadel, P.

    1998-01-01

    Synthetic gel and glass of illitic composition, natural kaolinite, and mixed-layer illite-smectite were used as starting materials for hydrothermal synthesis of ammonium illite. Ammonium illite was prepared from synthetic gel by hydrothermal treatment at 300??C. The onset of crystallization began within 3 h, and well-crystallized ammonium illite appeared at 24 h. Increasing reaction time (up to four weeks) led to many illite layers per crystal. In the presence of equivalent proportions of potassium and ammonium, the gel was transformed to illite with equimolar contents of K and NH4. In contrast, synthesis using glass under the same conditions resulted in a mixture of mixed-layer ammonium illite-smectite with large expandability and discrete illite. Hydrothermal treatments of the fine fractions of natural kaolinite and illite-smectite produced ammonium illite from kaolinite but the illite-smectite remained unchanged.

  18. Hydrothermal systems and volcano geochemistry

    USGS Publications Warehouse

    Fournier, R.O.

    2007-01-01

    The upward intrusion of magma from deeper to shallower levels beneath volcanoes obviously plays an important role in their surface deformation. This chapter will examine less obvious roles that hydrothermal processes might play in volcanic deformation. Emphasis will be placed on the effect that the transition from brittle to plastic behavior of rocks is likely to have on magma degassing and hydrothermal processes, and on the likely chemical variations in brine and gas compositions that occur as a result of movement of aqueous-rich fluids from plastic into brittle rock at different depths. To a great extent, the model of hydrothermal processes in sub-volcanic systems that is presented here is inferential, based in part on information obtained from deep drilling for geothermal resources, and in part on the study of ore deposits that are thought to have formed in volcanic and shallow plutonic environments.

  19. Introduction to Atlantic Hydrothermal Activity

    NASA Astrophysics Data System (ADS)

    Rona, Peter A.; Thompson, Geoffrey

    1993-06-01

    Seafloor hydrothermal research has advanced rapidly from local to global scope through a sequence of discoveries. Hydrothermal research at seafloor spreading centers began in the mid-1960s with the discovery of hot metalliferous brines and sediments ponded in deeps along the slow spreading (half rate 1 cm yr-1) axis of the Red Sea [Chamock, 1964; Miller, 1964; Swallow and Crease, 1965; Miller et al., 1966; Hunt et al., 1967; Bischoff, 1969]. At the same time a hydrothermal metalliferous component was identified in sediments of the East Pacific Rise [Skomyakova, 1965; Arrhenins and Bonatti, 1965; Boström and Peterson, 1966]. Geophysicists recognized that heat flow measurements at spreading centers could only be explained by convective cooling of the crust with circulating seawater [Elder, 1967; Lister, 1972].

  20. Investigation of the influence of liquid water films on O3 and PAN deposition on plant leaf surfaces treated with organic / inorganic compounds

    NASA Astrophysics Data System (ADS)

    Sun, Shang; Moravek, Alexander; von der Heyden, Lisa; Held, Andreas; Kesselmeier, Jürgen; Sörgel, Matthias

    2016-04-01

    Liquid water films on environmental surfaces play an important role in various fields of interest (Burkhardt and Eiden, 1994). For example, the deposition of water soluble trace gases could be increased by surface moisture. Chameides and Stelson (1992) found out that the dissolution of trace gases in airborne particulate matter increases with rising water/solid ratio of the particles. Further, Flechard et al. (1999) concluded that deliquescent salt particles represent a potential sink for trace gases, depending on their chemical property. The formation of surface water films and its influence on the gas deposition was proposed by many previous studies (Fuentes and Gillespie, 1992, Burkhardt and Eiden, 1994, van Hove et al., 1989, Burkhardt et al., 1999, Flechard et al., 1999). In this study we investigate the influence of leaf surface water films on the deposition of O3 and PAN under controlled laboratory conditions. A twin cuvette system described in Sun et al. (2015) was used to control the environmental parameters such as light, temperature, trace gas mixing ratio and humidity. Furthermore, the leaf surface was treated with various organic and inorganic solutions to investigate the influence of deposited compounds on the electrical surface conductance of the leaves and the surface deposition of O3 and PAN at various relative humidities. The result shows that RHcrit, where the electrical surface conductance (G) increases exponentially, was 40 % during the light period and 50 % during the dark period. Furthermore, we observed that the formation of the leaf surface liquid film was depended on the deposited compounds on the leaf cuticles. For the O3 deposition on plants (Quercus ilex) a clear enhancement at rising environmental air humidity under light and dark condition was found. The increase during light conditions can be related partly to increasing stomatal conductance with higher RH. From the non-stomatal deposition measured in dark experiments, we could

  1. Anaerobic digestion of post-hydrothermal liquefaction wastewater for improved energy efficiency of hydrothermal bioenergy processes.

    PubMed

    Zhou, Yan; Schideman, Lance; Zheng, Mingxia; Martin-Ryals, Ana; Li, Peng; Tommaso, Giovana; Zhang, Yuanhui

    2015-01-01

    Hydrothermal liquefaction (HTL) is a promising process for converting wet biomass and organic wastes into bio-crude oil. It also produces an aqueous product referred to as post-hydrothermal liquefaction wastewater (PHWW) containing up to 40% of the original feedstock carbon, which reduces the overall energy efficiency of the HTL process. This study investigated the feasibility of using anaerobic digestion (AD) to treat PHWW, with the aid of activated carbon. Results showed that successful AD occurred at relatively low concentrations of PHWW (≤ 6.7%), producing a biogas yield of 0.5 ml/mg CODremoved, and ∼53% energy recovery efficiency. Higher concentrations of PHWW (≥13.3%) had an inhibitory effect on the AD process, as indicated by delayed, slower, or no biogas production. Activated carbon was shown to effectively mitigate this inhibitory effect by enhancing biogas production and allowing digestion to proceed at higher PHWW concentrations (up to 33.3%), likely due to sequestering toxic organic compounds. The addition of activated carbon also increased the net energy recovery efficiency of AD with a relatively high concentration of PHWW (33.3%), taking into account the energy for producing activated carbon. These results suggest that AD is a feasible approach to treat PHWW, and to improve the energy efficiency of the HTL processes. PMID:26676001

  2. Anaerobic digestion of post-hydrothermal liquefaction wastewater for improved energy efficiency of hydrothermal bioenergy processes.

    PubMed

    Zhou, Yan; Schideman, Lance; Zheng, Mingxia; Martin-Ryals, Ana; Li, Peng; Tommaso, Giovana; Zhang, Yuanhui

    2015-01-01

    Hydrothermal liquefaction (HTL) is a promising process for converting wet biomass and organic wastes into bio-crude oil. It also produces an aqueous product referred to as post-hydrothermal liquefaction wastewater (PHWW) containing up to 40% of the original feedstock carbon, which reduces the overall energy efficiency of the HTL process. This study investigated the feasibility of using anaerobic digestion (AD) to treat PHWW, with the aid of activated carbon. Results showed that successful AD occurred at relatively low concentrations of PHWW (≤ 6.7%), producing a biogas yield of 0.5 ml/mg CODremoved, and ∼53% energy recovery efficiency. Higher concentrations of PHWW (≥13.3%) had an inhibitory effect on the AD process, as indicated by delayed, slower, or no biogas production. Activated carbon was shown to effectively mitigate this inhibitory effect by enhancing biogas production and allowing digestion to proceed at higher PHWW concentrations (up to 33.3%), likely due to sequestering toxic organic compounds. The addition of activated carbon also increased the net energy recovery efficiency of AD with a relatively high concentration of PHWW (33.3%), taking into account the energy for producing activated carbon. These results suggest that AD is a feasible approach to treat PHWW, and to improve the energy efficiency of the HTL processes.

  3. Hydrothermal treatment coupled with mechanical expression at increased temperature for excess sludge dewatering: influence of operating conditions and the process energetics.

    PubMed

    Wang, Liping; Zhang, Lei; Li, Aimin

    2014-11-15

    Dewatering is very important for excess sludge treatment and disposal. Hydrothermal treatment coupled with mechanical expression is a novel technology, in which a conventional pressure dewatering is combined with hydrothermal effect to realize an improved liquid/solids separation with low energy consumption. In this study, the process was performed by way of that the excess sludge was hydrothermally treated first and then the mechanical expression was employed immediately at increased temperature in two separate cells respectively. The results demonstrated that the mechanical expression employed at increased temperature showed a significant advantage than that at room temperature, given a further reduction of 19-47% of the moisture content. The dewatering process at room temperature was mostly depended on the effect of mechanical expression. Hydrothermal process, more importantly than mechanical effect at increased temperatures, seemed to govern the extent to which the dewatering process occurred. The dewatering began to show a positive effect when the temperature was exceeded the threshold temperature (between 120 and 150 °C). The residence time of 30 min promoted a substantial conversion in the sludge surface properties. After dewatering at temperatures of 180-210 °C, the moisture content decreased from 52 to 20% and the corresponding total water removal as filtrate was between 81 and 93%. It was observed that the moisture content of filter cake correlated with surface charge (Rp = -0.93, p < 0.05) and relative hydrophobicity (Rp = -0.99, p < 0.05). The calculated energy balance suggested that no additional external energy input is needed to support the dewatering process for excess sludge. The dewatering process needs an obviously lower energy input compared to thermal drying and electro-dewatering to produce a higher solids content cake.

  4. Hydrothermal carbonization of tobacco stalk for fuel application.

    PubMed

    Cai, Jiaxiao; Li, Bin; Chen, Chaoying; Wang, Jing; Zhao, Min; Zhang, Ke

    2016-11-01

    Tobacco stalks are an abundant biomass resource which are otherwise treated as waste. In this work, the effect of hydrothermal carbonization temperature and time on the structures, chemical compositions and combustion characteristics of hydrochars obtained from tobacco stalks were evaluated. The carbon content, higher heating value, and energy yield increased with accompanying decrease in hydrogen and oxygen contents with the increase of treatment temperature and time. The evolution of the H/C and O/C atomic ratios indicated dehydration and devolatilization processes occurred during hydrothermal carbonization. The weight loss, combustion range and characteristic temperatures of tobacco stalks were significantly modified after hydrothermal carbonization, resulting in higher ignition temperatures and higher energy density. The kinetics model, Coats-Redfern method revealed the activation energy of hydrochars in zone 2 and 3 were among 43.7-74.8kJ/mol and 46.7-85.8kJ/mol, respectively. Our results show that hydrothermal carbonization reaction can facilitate transforming tobacco stalks into energy-rich solid fuel. PMID:27589825

  5. Upgrading copper concentrate by hydrothermally converting chalcopyrite to digenite

    NASA Astrophysics Data System (ADS)

    Bartlett, Robert W.

    1992-06-01

    Chalcopyrite in copper flotation concentrates can be hydrothermally converted to digenite directly with oxygen in a continuous process, provided the oxygen supply rate is stoichiomet-rically matched to the chalcopyrite feed rate. Substantial elimination of iron and sulfur can result and may be used to significantly increase smelter copper throughput. A simple process flowsheet is described with only three steps: regrind, hydrothermal conversion, and solid/liquid separa-tion. Fine particle size and autoclave temperatures above 200 °C provide a high conversion yield in residence times less than 1 hour using a single-stage mixing autoclave with good gas dis-persion. Extrapolated kinetic data from monosize particle batch conversion experiments were coupled with particle size distributions and ideal back-mix reactor residence time distributions to compute process yields for a continuous reactor. Optimum processing conditions are deduced.

  6. Hydrothermal processes at seafloor spreading centers,

    SciTech Connect

    Rona, P.A.; Bostrom, K.; Laubier, L.; Smith, K.L.

    1983-01-01

    This book examines research on the description and interpretation of hydrothermal and associated phenomena at seafloor spreading centers. An interdisciplinary overview of the subject is presented, including geological, geophysical, geochemical, and biological discoveries. The implications of the discoveries for understanding the earth's heat transfer, geochemical mass balances and cycles, mineralization, and biological adaptation are discussed. Topics considered include geologic setting (e.g., the four dimensions of the spreading axis, geological processes of the mid-ocean ridge), hydrothermal convection (e.g., oxygen and hydrogen isotope studies, the basic physics of water penetration into hot rock), Iceland and oceanic ridges (e.g., chemical evidence from Icelandic geothermal systems, the physical environment of hydrothermal systems), mass balances and cycles (e.g., reduced gases and bacteria in hydrothermal fluids, the effects of hydrothermal activity on sedimentary organic matter), ferromanganese deposits, hydrothermal mineralization, and the biology of hydrothermal vents.

  7. Hydrothermal pretreatment conditions to enhance ethanol production from poplar biomass.

    PubMed

    Negro, Maria José; Manzanares, Paloma; Ballesteros, Ignacio; Oliva, Jose Miguel; Cabañas, Araceli; Ballesteros, Mercedes

    2003-01-01

    Pretreatment has been recognized as a key step in enzyme-based conversion processes of lignocellulose biomass to ethanol. The aim of this study is to evaluate two hydrothermal pretreatments (steam explosion and liquid hot water) to enhance ethanol production from poplar (Populus nigra) biomass by a simultaneous saccharification and fermentation (SSF) process. The composition of liquid and solid fractions obtained after pretreatment, enzymatic digestibility, and ethanol production of poplar biomass pretreated at different experimental conditions was analyzed. The best results were obtained in steam explosion pretreatment at 210 C and 4 min, taking into account cellulose recovery above 95%, enzymatic hydrolysis yield of about 60%, SSF yield of 60% of theoretical, and 41% xylose recovery in the liquid fraction. Large particles can be used for poplar biomass in both pretreatments, since no significant effect of particle size on enzymatic hydrolysis and SSF was obtained.

  8. The migration and transformation behaviors of heavy metals during the hydrothermal treatment of sewage sludge.

    PubMed

    Huang, Hua-Jun; Yuan, Xing-Zhong

    2016-01-01

    Various hydrothermal treatment methods, including hydrothermal carbonization, liquefaction and sub/super-critical water gasification, have been applied to the disposal of sewage sludge for producing bio-materials or bio-fuels. It has become a research hotspot whether the heavy metals contained in sewage sludge can be well treated/stabilized after the hydrothermal treatments. This review firstly summarized the methods of assessing heavy metals' contamination level/risk and then discussed the migration and transformation behaviors of heavy metals from the following aspects: the effect of reaction temperature, the effect of additives (catalysts and other biomass), the effect of the type of solvent and the effect of reaction time. This review can provide an important reference for the further study of the migration and transformation behaviors of heavy metals during the hydrothermal treatment of sewage sludge. PMID:26577578

  9. Boron isotope systematics of hydrothermal fluids from submarine hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Yamaoka, K.; Hong, E.; Ishikawa, T.; Gamo, T.; Kawahata, H.

    2013-12-01

    Boron is highly mobile in submarine hydrothermal systems and useful to trace the process of water-rock reaction. In this study, we measured the boron content and isotopic composition of vent fluids collected from arc-backarc hydrothermal systems in the western Pacific. In sediment-starved hydrothermal systems (Manus Basin, Suiyo Seamount, and Mariana Trough), the boron content and isotopic composition of vent fluids are dependent on type of host rock. The end member fluids from MORB-like basalt-hosted Vienna Woods in the Manus Basin showed low boron content and high δ11B value (0.53 mM, 29.8‰), while dacite-hosted PACMANUS and the Suiyo Seamount showed high boron contents and low δ11B values (1.45 and 1.52 mM, 13.6 and 18.5‰, respectively). The Alice Springs and Forecast Vent field in the Mariana Trough showed values intermediate between them (0.72 and 0.63 mM, 19.9 and 24.0‰, respectively), reflecting reaction of seawater and basalt influenced by slab material. In phase separated hydrothermal systems (North Fiji Basin), boron content and isotopic composition of vent fluids (0.44-0.56 mM, 34.5-35.9‰) were similar to those in the Vienna Woods. Considering little fractionation of boron and boron isotope during phase separation demonstrated by the previous experimental studies, it is suggested that the host rock in the North Fiji Basin is MORB-like basalt. In sediment-hosted hydrothermal system (Okinawa Trough), the reaction with boron-enriched sediment following seawater-rock reaction resulted in significantly high boron contents and low δ11B values of vent fluids (4.4-5.9 mM, 1.5-2.6‰). The water-sediment ratio was estimated to be ~2. In spite of the different geological settings, the end member fuids from all vent fields are enriched in B relative to seawater (0.41 mM, 39.6‰) and the δ11B values are inversely propotional to the boron concentrations. It suggests that boron isotopic composition of vent fluid predominantly depends on the amount of

  10. Magmatic contributions to hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Muffler, L. J. Patrick; Hedenquist, Jeffrey W.; Kesler, Stephen E.; Izawa, Eiji

    Although there is agreement that many hydrothermal systems in the upper crust derive their thermal energy from magmas, debate continues over the extent to which magmas contribute water, metals, and sulfur to hydrothermal systems. A multidisciplinary seminar was held November 10-16, 1991, in Ebino and Kagoshima, Japan, to establish current understanding about this topic and to explore the major unanswered questions and the most promising research directions. The thirty-eight participants were from Japan (eighteen), the U.S. (thirteen), Canada and New Zealand (two each), and England, the Philippines, and Russia (one each). Disciplines represented were volcanology, geochemistry (volcanic-gas, water, isotopes, experimental, and modeling), igneous petrology, geothermal geology, economic geology, fluid-inclusion study, geophysics, and physical modeling.

  11. POLAR ORGANIC CHEMICAL INTEGRATIVE SAMPLING AND LIQUID CHROMATOGRAPHY-ELECTROSPRAY/ION-TRAP MASS SPECTROMETRY FOR ASSESSING SELECTED PRESCRIPTION AND ILLICIT DRUGS IN TREATED SEWAGE EFFLUENTS

    EPA Science Inventory

    The purpose of the research presented in this paper is two-fold: (1) to demonstrate the 4 coupling of two state-of-the-art techniques: a time-weighted polar organic integrative sampler (POCIS) and micro-liquid chromatography-electrospray/ion trap mass spectrometry (u-LC-6 ES/ITMS...

  12. Properties of plant nutrient: Comparison of two nutrient recovery techniques using liquid fraction of digestate from anaerobic digester treating pig manure.

    PubMed

    Li, Xin; Guo, Jianbin; Dong, Renjie; Ahring, Birgitte K; Zhang, Wanqin

    2016-02-15

    Anaerobic digestate has valuable potential as organic fertilizer or soil amendment, given that it typically contains high amounts of plant nutrients, such as nitrogen, phosphate and plant hormones. In this study, ammonia stripping and vacuum evaporation were tested to compare their technical feasibilities and their effects on plant nutrient properties in the liquid fraction of digestate. Results of the batch experiments showed that the nutrient characteristics of liquid digestate, including total ammonia nitrogen (TAN), soluble P, gibberellic acid (GA), indoleacetic acid (IAA) and abscisic acid (ABA), were strongly dependent on the initial pH in both ammonia stripping and vacuum evaporation processes. A low plant nutrient concentration (TAN 137 mg · L(-1), soluble P 1.5 mg · L(-1), GA3/ABA 0.04) in the liquid digestate was achieved in the ammonia stripping process with Ca(OH)2 addition of 12 g · L(-1), whereas a high nutrient concentration (TAN 2998 mg · L(-1), soluble P 178.3 mg · L(-1), IAA 60.9 mg · L(-1) and GA3/ABA 0.4) was achieved in vacuum evaporation at a pH level of 6. According to the results, both ammonia stripping and vacuum evaporation can be used as an alternative of nutrient recovery techniques, which should be chosen based on the potential different applications of liquid digestate (e.g., soaking seed, increasing plant tolerance, and nutrients transportation).

  13. Properties of plant nutrient: Comparison of two nutrient recovery techniques using liquid fraction of digestate from anaerobic digester treating pig manure.

    PubMed

    Li, Xin; Guo, Jianbin; Dong, Renjie; Ahring, Birgitte K; Zhang, Wanqin

    2016-02-15

    Anaerobic digestate has valuable potential as organic fertilizer or soil amendment, given that it typically contains high amounts of plant nutrients, such as nitrogen, phosphate and plant hormones. In this study, ammonia stripping and vacuum evaporation were tested to compare their technical feasibilities and their effects on plant nutrient properties in the liquid fraction of digestate. Results of the batch experiments showed that the nutrient characteristics of liquid digestate, including total ammonia nitrogen (TAN), soluble P, gibberellic acid (GA), indoleacetic acid (IAA) and abscisic acid (ABA), were strongly dependent on the initial pH in both ammonia stripping and vacuum evaporation processes. A low plant nutrient concentration (TAN 137 mg · L(-1), soluble P 1.5 mg · L(-1), GA3/ABA 0.04) in the liquid digestate was achieved in the ammonia stripping process with Ca(OH)2 addition of 12 g · L(-1), whereas a high nutrient concentration (TAN 2998 mg · L(-1), soluble P 178.3 mg · L(-1), IAA 60.9 mg · L(-1) and GA3/ABA 0.4) was achieved in vacuum evaporation at a pH level of 6. According to the results, both ammonia stripping and vacuum evaporation can be used as an alternative of nutrient recovery techniques, which should be chosen based on the potential different applications of liquid digestate (e.g., soaking seed, increasing plant tolerance, and nutrients transportation). PMID:26674705

  14. Quantitative analysis of the Lassen hydrothermal systems, North Central California

    SciTech Connect

    Ingerbritsen, S.E.; Sorey, M.L.

    1985-06-01

    This conceptual model of the Lassen system is termed a liquid-dominated hydrothermal system with a parasitic vapor-dominated zone. The essential feature of this model is that steam and steam-heated discharge at relatively high altitudes in Lassen Volcanic National Park (LVNP) and liquid discharge with high chloride concentrations at relatively low altitudes outside LVNP are both fed by an upflow of high-enthalpy two-phase fluid with the Park. Liquid flows laterally away from the upflow area toward the areas of high-chloride discharge, and steam rises through a vapor-dominated zone to feed the steam and steam-heated features. Numerical simulations show that several conditions are necessary for the development of this type of system, including large-scale topographic relief; an initial period of convective heating within an upflow zone followed by a change in hydrologic or geologic conditions that initiates drainage of liquid from portions of the upflow zone; and low-permeability barriers that inhibit the movement of cold water into the vapor zone. Simulations of thermal fluid withdrawal south of LVNP, carried out in order to determine the effects of such withdrawal on portions of the hydrothermal system within the Park, generally showed decreases in pressure and liquid saturation beneath the vapor zone which resulted in temporary increases and subsequent decreases in the rate of upflow of steam. A generalized production-injection scenario that could mitigate the effects of development on both the high-chloride and steam-fed features was identified.

  15. The production of glucose from corn stalk using hydrothermal process with pre-treatment ultrasound assisted alkaline

    NASA Astrophysics Data System (ADS)

    Yolanda, Dora; Prasutiyo, Indry; Trisanti, P. N.; Sumarno

    2015-12-01

    The production of glucose from corn stalk by using subcritical hydrothermal technology is studied in this work. Ultrasound-assisted alkaline delignification methods are used as pre-treatment. The corn stalk powder were pretreated with ultrasound-assisted alkaline (NaOH 2% w/w, solid to liquid ratio 1:22 w/v) at room temperature and 30 minutes. After pre-treatment, solid residue and liquid fractions are separated by filtration. Pretreated solids are further submitted to hydrothermal process for glucose production. Hydrothermal process was carried out at 100 Bar and 120°C in various times. The solid product was characterized by SEM and XRD. And liquid product was analysis using DNS method to determine percentage of glucose. From XRD analysis showed that crystallinity of material was lower than delignification product.

  16. Enceladus as a hydrothermal water world

    NASA Astrophysics Data System (ADS)

    Postberg, Frank; Hsu, Hsiang-Wen; Sekine, Yasuhito

    2014-05-01

    The composition of both salty ice grains and nanometer-sized stream particles emitted from Enceladus and measured by Cassini-CDA require require liquid water as a source. Moreover, they provide strong geochemical constraints for their origin inside the active moon. Most stream particles are composed of silica, a unique indicator as nano-silica would only form under quite specific conditions. With high probability on-going or geological recent hydrothermal activity at Enceladus is required to generate these particles. Inferred reaction temperatures at Enceladus ocean floor lie between 100 and 350 °C in a slightly alkaline environment (pH 7.5 - 10.5). The inferred high temperatures at great depth might require heat sources other than tides alone, such as remaining primordial heat and/or serpentinization of a probably porous rocky core. Long-term laboratory experiments were carried out to simulate the conditions at the Enceladus rock/water interface using the constraints derived from CDA measurements. These experiments allow insights into a rock/water chemistry which severely constrains the formation history of the moon and substantially enhances its astrobiological potential. Together with recent results from other Cassini instruments a conclusive picture of Enceladus as an active water world seems to be in reach.

  17. Hydrothermal Habitats: Measurements of Bulk Microbial Elemental Composition, and Models of Hydrothermal Influences on the Evolution of Dwarf Planets

    NASA Astrophysics Data System (ADS)

    Neveu, Marc Francois Laurent

    Finding habitable worlds is a key driver of solar system exploration. Many solar system missions seek environments providing liquid water, energy, and nutrients, the three ingredients necessary to sustain life. Such environments include hydrothermal systems, spatially-confined systems where hot aqueous fluid circulates through rock by convection. I sought to characterize hydrothermal microbial communities, collected in hot spring sediments and mats at Yellowstone National Park, USA, by measuring their bulk elemental composition. To do so, one must minimize the contribution of non-biological material to the samples analyzed. I demonstrate that this can be achieved using a separation method that takes advantage of the density contrast between cells and sediment and preserves cellular elemental contents. Using this method, I show that in spite of the tremendous physical, chemical, and taxonomic diversity of Yellowstone hot springs, the composition of microorganisms there is surprisingly ordinary. This suggests the existence of a stoichiometric envelope common to all life as we know it. Thus, future planetary investigations could use elemental fingerprints to assess the astrobiological potential of hydrothermal settings beyond Earth. Indeed, hydrothermal activity may be widespread in the solar system. Most solar system worlds larger than 200 km in radius are dwarf planets, likely composed of an icy, cometary mantle surrounding a rocky, chondritic core. I enhance a dwarf planet evolution code, including the effects of core fracturing and hydrothermal circulation, to demonstrate that dwarf planets likely have undergone extensive water-rock interaction. This supports observations of aqueous products on their surfaces. I simulate the alteration of chondritic rock by pure water or cometary fluid to show that aqueous alteration feeds back on geophysical evolution: it modifies the fluid antifreeze content, affecting its persistence over geological timescales; and the

  18. Effect of hydrothermal treatment on the levels of selected indigenous microbes in food waste.

    PubMed

    Chen, Ting; Jin, Yiying; Liu, Fuqiang; Meng, Xiao; Li, Huan; Nie, Yongfeng

    2012-09-15

    The ability of hydrothermal treatment to reduce or eliminate selected indicator organisms in food waste was assessed in this study. Raw food waste collected from student canteens at Tsinghua University was heat-treated under hydrothermal conditions at 90-140 °C for 10-40 min. Hydrothermal inactivation analyses were carried out on four types of indigenous microbes used as indicators of hygiene: molds and yeasts (MY), total coliforms (TC), total aerobic counts (TAC) and Staphylococcus aureus (SA). Significant reductions in the levels of indigenous microbes in food waste were achieved during the ramping and holding periods of the hydrothermal treatment, and the microbial inactivation effect increased with increasing temperature, increasing time and increasing pressure. Due to the typical properties of food waste, hydrothermal treatment at 120 °C-0.3 MPa for at least 40 min was sufficient to achieve complete sterilization of the food waste. The results showed that hydrothermal treatment could significantly reduce the levels of indigenous microbes and is a potential advanced technique for the sterilization of food waste with a high moisture content in China.

  19. Optimizing an Experimental System for Assessing the Amounts and Forms of Copper Released into Aquatic Systems from Commercially Available Liquid and Micronized Pressure Treated Lumber

    EPA Science Inventory

    The fate and effects of pristine engineered metal nanomaterials (ENMs) in simplified systems have been widely studied; however, little is known about the potential release and impact of metal ENMs from consumer goods, especially lumber which has been treated with micronized coppe...

  20. Pyrolysis of hydrochar from digestate: Effect of hydrothermal carbonization and pyrolysis temperatures on pyrochar formation.

    PubMed

    Garlapalli, Ravinder K; Wirth, Benjamin; Reza, M Toufiq

    2016-11-01

    Digestate from anaerobic digestion of biomass often contains more than 90% of water, which is economically unfavorable for pyrolysis. Hydrothermal carbonization (HTC) has potential to treat very wet biomass, however, the hydrochar may be acidic, contains polycyclic aromatic hydrocarbons (PAH) and toxic organic substances (e.g., phenolic compounds), and has very low Brunauer-Emmett-Teller (BET) surface area. In this study, pyrolysis of digestate derived hydrochar is performed at various pyrolysis and HTC temperatures. Solid chars were characterized for elemental analysis, pH, PAH, BET, pore size and volume, and phenolic substances, while HTC process liquids were characterized for pH, organic acids, furfural derivatives, and phenolic substances. Physicochemical characteristics of pyro-HTC char were compared with corresponding pyrochar and hydrochar. Pyro-HTC chars produced at higher HTC (i.e., 260°C) and pyrolysis temperatures (i.e., 800°C) showed highest BET surface area (63.5m(2)g(-1)), no PAH, relatively mild basic pH (9.34), and no phenolic compounds. PMID:27567477

  1. Magmatic intrusions and hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Gulick, Virginia Claire

    1993-01-01

    This dissertation investigates the possible role of hydrothermally driven ground-water outflow in the formation of fluvial valleys on Mars. Although these landforms have often been cited as evidence for a past warmer climate and denser atmosphere, recent theoretical modeling precludes such climatic conditions on early Mars when most fluvial valleys formed. Because fluvial valleys continued to form throughout Mars' geological history and the most Earth-like stream valleys on Mars formed well after the decline of the early putative Earth-like climate, it may be unnecessary to invoke drastically different climatic conditions for the formation of the earliest stream valleys. The morphology of most Martian fluvial valleys indicates formation by ground-water sapping which is consistent with a subsurface origin. Additionally, many Martian fluvial valleys formed on volcanoes, impact craters, near fractures, or adjacent to terrains interpreted as igneous intrusions; all are possible locales of vigorous, geologically long-lived hydrothermal circulation. Comparison of Martian valley morphology to similar features on Earth constrains valley genesis scenarios. Volumes of measured Martian fluvial valleys range from 1010 to 1013 m3. Based on terrestrial analogs, total water volumes required to erode these valleys range from approximately 1010 to 1015 m3. The clustered distribution of Martian valleys within a given terrain type, the sapping dominated morphology, and the general lack of associated runoff valleys all indicate the importance of localized ground-water outflow in the formation of these fluvial systems. An analytic model of a conductively cooling cylindrical intrusion is coupled with the U.S. Geological Survey's numerical ground-water computer code SUTRA to evaluate the magnitude of ground-water outflow expected from magmatically-driven hydrothermal systems on Mars. Results indicate that magmatic intrusions of several 102 km3 or larger can provide sufficient ground

  2. Influence of process water quality on hydrothermal carbonization of cellulose.

    PubMed

    Lu, Xiaowei; Flora, Joseph R V; Berge, Nicole D

    2014-02-01

    Hydrothermal carbonization (HTC) is a thermal conversion process that has been shown to be environmentally and energetically advantageous for the conversion of wet feedstocks. Supplemental moisture, usually in the form of pure water, is added during carbonization to achieve feedstock submersion. To improve process sustainability, it is important to consider alternative supplemental moisture sources. Liquid waste streams may be ideal alternative liquid source candidates. Experiments were conducted to systematically evaluate how changes in pH, ionic strength, and organic carbon content of the initial process water influences cellulose carbonization. Results from the experiments conducted evaluating the influence of process water quality on carbonization indicate that changes in initial water quality do influence time-dependent carbonization product composition and yields. These results also suggest that using municipal and industrial wastewaters, with the exception of streams with high CaCl2 concentrations, may impart little influence on final carbonization products/yields.

  3. Hydrothermal Processing of Macroalgal Feedstocks in Continuous-Flow Reactors

    SciTech Connect

    Elliott, Douglas C.; Hart, Todd R.; Neuenschwander, Gary G.; Rotness, Leslie J.; Roesijadi, Guri; Zacher, Alan H.; Magnuson, Jon K.

    2014-02-03

    Wet macroalgal slurries have been converted into a biocrude by hydrothermal liquefaction (HTL) in a bench-scale continuous-flow reactor system. Carbon conversion to a gravity-separable oil product of 58.8% was accomplished at relatively low temperature (350 °C) in a pressurized (subcritical liquid water) environment (20 MPa) when using feedstock slurries with a 21.7% concentration of dry solids. As opposed to earlier work in batch reactors reported by others, direct oil recovery was achieved without the use of a solvent, and biomass trace mineral components were removed by processing steps so that they did not cause processing difficulties. In addition, catalytic hydrothermal gasification (CHG) was effectively applied for HTL byproduct water cleanup and fuel gas production from water-soluble organics. Conversion of 99.2% of the carbon left in the aqueous phase was demonstrated. Finally, as a result, high conversion of macroalgae to liquid and gas fuel products was found with low levels of residual organic contamination in byproduct water. Both process steps were accomplished in continuous-flow reactor systems such that design data for process scale-up was generated.

  4. Whole Algae Hydrothermal Liquefaction Technology Pathway

    SciTech Connect

    Biddy, M.; Davis, R.; Jones, S.

    2013-03-01

    This technology pathway case investigates the feasibility of using whole wet microalgae as a feedstock for conversion via hydrothermal liquefaction. Technical barriers and key research needs have been assessed in order for the hydrothermal liquefaction of microalgae to be competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks.

  5. Thermodynamics of uranium/organic matter interactions in hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Richard, L.

    2003-04-01

    Organic matter is commonly encountered in and around uranium and other ore deposits, which raises the question of the role played by organic compounds in the formation of these deposits (Landais and Gize, 1997). One of the best known examples is the observation of uraninite crystals entrapped within solid bitumens in the Oklo natural reactors. This observation led Nagy et al. (1991) to propose that a liquid, aliphatic-rich bitumen may have acted as a reductant to precipitate uraninite from hydrothermal solutions according to the reaction VIUO2+2(aq)+H_2O(l)=IVUO2(c)+2H^+(aq)+0.5 O2(g). The liquid bitumen was simultaneously oxidized into a polyaromatic solid, which may be represented by the reaction 2.7n- C20H42(l) + 17.85 O2(g) = C54H42(c)+35.7 H_2O(l) where n-C20H42(l) denotes n-eicosane present in the liquid bitumen, and C54H42(c) represents an idealized polyaromatic solid. Recent advances in theoretical organic geochemistry made it possible to generate a comprehensive thermodynamic database for hundreds of crystalline, liquid, gas and aqueous organic compounds of geochemical interest (Shock and Helgeson, 1990; Shock, 1995; Amend and Helgeson, 1997; Helgeson et al., 1998; Richard and Helgeson, 1998; Richard, 2001), which can be used together with thermodynamic properties for uranium-bearing minerals and aqueous species (Grenthe et al., 1992; Shock et al., 1997) to characterize uranium/organic matter interactions in hydrothermal systems as a function of temperature, pressure, oxygen fugacity, and organic matter composition. Activity-fO_2 diagrams have been constructed at a series of temperatures and pressures to investigate possible genetic relationships between uranium mineralizations and solid bitumens of various compositions.

  6. Hydrothermal origin for carbonate globules in Martian meteorite ALH84001: a terrestrial analogue from Spitsbergen (Norway)

    NASA Astrophysics Data System (ADS)

    Treiman, Allan H.; Amundsen, Hans E. F.; Blake, David F.; Bunch, Ted

    2002-12-01

    Carbonate minerals in the ancient Martian meteorite ALH84001 are the only known solid phases that bear witness to the processing of volatile and biologically critical compounds (CO 2, H 2O) on early Mars. Similar carbonates have been found in xenoliths and their host basalts from Quaternary volcanic centers in northern Spitsbergen (Norway). These carbonates were deposited by hot (i.e., hydrothermal) waters associated with the volcanic activity. By analogy with the Spitsbergen carbonates, the ALH84001 carbonates were probably also deposited by hot water. Hydrothermal activity was probably common and widespread on Early Mars, which featured abundant basaltic rocks, water as ice or liquid, and heat from volcanos and asteroid impacts. On Earth, descendants of the earliest life forms still prefer hydrothermal environments, which are now shown to have been present on early Mars.

  7. A review on hydrothermal pre-treatment technologies and environmental profiles of algal biomass processing.

    PubMed

    Patel, Bhavish; Guo, Miao; Izadpanah, Arash; Shah, Nilay; Hellgardt, Klaus

    2016-01-01

    The need for efficient and clean biomass conversion technologies has propelled Hydrothermal (HT) processing as a promising treatment option for biofuel production. This manuscript discussed its application for pre-treatment of microalgae biomass to solid (biochar), liquid (biocrude and biodiesel) and gaseous (hydrogen and methane) products via Hydrothermal Carbonisation (HTC), Hydrothermal Liquefaction (HTL) and Supercritical Water Gasification (SCWG) as well as the utility of HT water as an extraction medium and HT Hydrotreatment (HDT) of algal biocrude. In addition, the Solar Energy Retained in Fuel (SERF) using HT technologies is calculated and compared with benchmark biofuel. Lastly, the Life Cycle Assessment (LCA) discusses the limitation of the current state of art as well as introduction to new potential input categories to obtain a detailed environmental profile. PMID:26514623

  8. A review on hydrothermal pre-treatment technologies and environmental profiles of algal biomass processing.

    PubMed

    Patel, Bhavish; Guo, Miao; Izadpanah, Arash; Shah, Nilay; Hellgardt, Klaus

    2016-01-01

    The need for efficient and clean biomass conversion technologies has propelled Hydrothermal (HT) processing as a promising treatment option for biofuel production. This manuscript discussed its application for pre-treatment of microalgae biomass to solid (biochar), liquid (biocrude and biodiesel) and gaseous (hydrogen and methane) products via Hydrothermal Carbonisation (HTC), Hydrothermal Liquefaction (HTL) and Supercritical Water Gasification (SCWG) as well as the utility of HT water as an extraction medium and HT Hydrotreatment (HDT) of algal biocrude. In addition, the Solar Energy Retained in Fuel (SERF) using HT technologies is calculated and compared with benchmark biofuel. Lastly, the Life Cycle Assessment (LCA) discusses the limitation of the current state of art as well as introduction to new potential input categories to obtain a detailed environmental profile.

  9. Sensitive determination of organic acid preservatives in juices and soft drinks treated by monolith-based stir cake sorptive extraction and liquid chromatography analysis.

    PubMed

    Lin, Fuhua; Nong, Shuyu; Huang, Xiaojia; Yuan, Dongxing

    2013-02-01

    A simple, efficient, and sensitive method for simultaneous determination of sorbic acid (SA), benzoic acid (BA), and cinnamic acid (CA) in juices and soft drinks was developed by stir cake sorptive extraction (SCSE) coupling to high-performance liquid chromatography with diode array detection. The SCSE based on polymeric ionic liquid-based monolith (PILM) as extractive medium was used to concentrate these three organic acid preservatives. Because hydrophobic and ion-exchange interactions co-contributed to the extraction, the PILM-SCSE exhibited a high extractive capability towards analytes. To obtain optimum extraction performance, several SCSE parameters were investigated and discussed, including desorption solvent, pH value, ionic strength in the sample matrix, and the extraction and desorption time. Under the optimized extraction conditions, limits of detection of 0.16, 1.08, and 0.18 μg/L (S/N=3) and quantification limits of 0.52, 3.42, and 0.61 (S/N=10) were obtained for SA, BA, and CA, respectively. The method also showed good linearity and reproducibility, as well as advantages such as simplicity, low cost, and high feasibility. Finally, the proposed method was successfully applied to the determination of SA, BA, and CA in real juices and soft drinks, and the recoveries ranged from 63.0 to 107 %.

  10. Fluidized bed heat treating system

    SciTech Connect

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06

    Systems for heat treating materials are presented. The systems typically involve a fluidized bed that contains granulated heat treating material. In some embodiments a fluid, such as an inert gas, is flowed through the granulated heat treating medium, which homogenizes the temperature of the heat treating medium. In some embodiments the fluid may be heated in a heating vessel and flowed into the process chamber where the fluid is then flowed through the granulated heat treating medium. In some embodiments the heat treating material may be liquid or granulated heat treating material and the heat treating material may be circulated through a heating vessel into a process chamber where the heat treating material contacts the material to be heat treated. Microwave energy may be used to provide the source of heat for heat treating systems.

  11. Characteristics of solids, BOD5 and VFAs in liquid swine manure treated by short-term low-intensity aeration for long-term storage.

    PubMed

    Zhang, ZhiJian; Zhu, Jun

    2006-01-01

    A laboratory-scale experiment presents data that reveal the temporal characteristics of solids, biochemical oxygen demand (BOD5) and volatile fatty acids (VFAs) in the aerated liquid swine manure for minimizing odor generation potential during 190-day storage. The performance of 15-day aeration of liquid manure with initial total solids (TS) content from 0.5% to 4.0% was examined at low-intensity aeration rates, i.e., +35 mV oxidation-reduction potential (ORP), 1.0 mg O2/l and 3.0 mg O2/l dissolved oxygen (DO). Odor generation potential was evaluated using VFAs. The aeration process contributed remarkably to the decomposition of TS, total volatile solids (TVS), BOD5 and VFAs. Moreover, the stabilization of manure due to aeration could last up to 190 days. The TS reduction on day 190 ranging from 6.3% to 32.7%, 20.2% to 39.1%, 19.0% to 41.0% were realized under the intensities of +35 mV ORP, 1.0 and 3.0 mg O2/l, respectively. At the same time, the reduction of BOD5 and VFAs reached around 7.8% to 69.5%, 17.2% to 79.9% and 21.9% to 91.1%; 0.4% to 91.0%, 60.4% to 95.0% and 70.4% to 94.1%. The liquid manure with low solids (e.g., TS of 0.5% and 1.0%) offered an advantageous condition for aeration treatment, particularly for biodegradation of BOD5 and VFAs. The odor generation potential could also be evaluated by the levels of solids and BOD5 in the manure. Increasing aeration intensity would significantly diminish the odor generation potential for given levels of solids and/or BOD5. Fifteen-day aeration with intensity of 1.0 mg O2/l may be recommended at farm level for both odor control and energy savings.

  12. Suspect screening of emerging pollutants and their major transformation products in wastewaters treated with fungi by liquid chromatography coupled to a high resolution mass spectrometry.

    PubMed

    Llorca, Marta; Lucas, Daniel; Ferrando-Climent, Laura; Badia-Fabregat, Marina; Cruz-Morató, Carles; Barceló, Damià; Rodríguez-Mozaz, Sara

    2016-03-25

    A new approach for the screening of 33 pharmaceuticals and 113 of their known transformation products in wastewaters was developed. The methodology is based on the analysis of samples by liquid chromatography coupled to high resolution mass spectrometry (HRMS) followed by data processing using specific software and manual confirmation. A home-made library was built with the transformation products reported in literature for the target pharmaceuticals after treatment with various fungi. The method was applied to the search of these contaminants in 67 samples generated along treatment of wastewaters with white-rot fungus Trametes versicolor. The screening methodology allowed the detection of different transformation products (TPs) generated from degradation of parent compounds after fungal treatment. This approach can be a useful tool for the rapid screening and tentative detection of emerging contaminants during water treatment in both full and batch-scale studies when pure standards are not available.

  13. Suspect screening of emerging pollutants and their major transformation products in wastewaters treated with fungi by liquid chromatography coupled to a high resolution mass spectrometry.

    PubMed

    Llorca, Marta; Lucas, Daniel; Ferrando-Climent, Laura; Badia-Fabregat, Marina; Cruz-Morató, Carles; Barceló, Damià; Rodríguez-Mozaz, Sara

    2016-03-25

    A new approach for the screening of 33 pharmaceuticals and 113 of their known transformation products in wastewaters was developed. The methodology is based on the analysis of samples by liquid chromatography coupled to high resolution mass spectrometry (HRMS) followed by data processing using specific software and manual confirmation. A home-made library was built with the transformation products reported in literature for the target pharmaceuticals after treatment with various fungi. The method was applied to the search of these contaminants in 67 samples generated along treatment of wastewaters with white-rot fungus Trametes versicolor. The screening methodology allowed the detection of different transformation products (TPs) generated from degradation of parent compounds after fungal treatment. This approach can be a useful tool for the rapid screening and tentative detection of emerging contaminants during water treatment in both full and batch-scale studies when pure standards are not available. PMID:26553957

  14. Effect of hydrothermal treatment on properties of Ni-Al layered double hydroxides and related mixed oxides

    SciTech Connect

    Kovanda, Frantisek Rojka, Tomas; Bezdicka, Petr; Jiratova, Kveta; Obalova, Lucie; Pacultova, Katerina; Bastl, Zdenek; Grygar, Tomas

    2009-01-15

    The Ni-Al layered double hydroxides (LDHs) with Ni/Al molar ratio of 2, 3, and 4 were prepared by coprecipitation and treated under hydrothermal conditions at 180 deg. C for times up to 20 h. Thermal decomposition of the prepared samples was studied using thermal analysis and high-temperature X-ray diffraction. Hydrothermal treatment increased significantly the crystallite size of coprecipitated samples. The characteristic LDH diffraction lines disappeared completely at ca. 350 deg. C and a gradual crystallization of NiO-like mixed oxide was observed at higher temperatures. Hydrothermal treatment improved thermal stability of the Ni2Al and Ni3Al LDHs but only a slight effect of hydrothermal treatment was observed with the Ni4Al sample. The Rietveld refinement of powder XRD patterns of calcination products obtained at 450 deg. C showed a formation of Al-containing NiO-like oxide and a presence of a considerable amount of Al-rich amorphous component. Hydrothermal aging of the LDHs resulted in decreasing content of the amorphous component and enhanced substitution of Al cations into NiO-like structure. The hydrothermally treated samples also exhibited a worse reducibility of Ni{sup 2+} components. The NiAl{sub 2}O{sub 4} spinel and NiO still containing a marked part of Al in the cationic sublattice were detected in the samples calcined at 900 deg. C. The Ni2Al LDHs hydrothermally treated for various times and related mixed oxides obtained at 450 deg. C showed an increase in pore size with increasing time of hydrothermal aging. The hydrothermal treatment of LDH precursor considerably improved the catalytic activity of Ni2Al mixed oxides in N{sub 2}O decomposition, which can be explained by suppressing internal diffusion effect in catalysts grains. - Graphical Abstract: Hydrothermal treatment of Ni-Al LDH precursors influenced the porous structure of related mixed oxides and considerably improved their catalytic activity in N{sub 2}O decomposition; the higher catalytic

  15. Geochemistry of some gases in hydrothermal fluids from the southern Juan de Fuca Ridge

    USGS Publications Warehouse

    Evans, William C.; White, L.D.; Rapp, J.B.

    1988-01-01

    Five samples of hydrothermal fluids from two vent areas on the southern Juan de Fuca Ridge were analyzed for dissolved gases. Concentrations in the end-member hydrothermal fluid of H2 (270-527 ??mol/kg), CH4 (82-118 ??mol/kg), and CO2 (3920-4460 ??mol/kg) are well above values in ambient seawater and are similar to concentrations reported for other ridge crest hydrothermal systems. The carbon isotopic ratios of the CH4(??13C=-17.8 to -20.8) and CO2(??13C=-3.6 to -4.7) suggest that at least some of the CH4 and CO2 in the fluids is basalt-derived. The range of ??13C values for the basalt-derived CO2 is -6.8 to -9.7, calculated by assuming conservation of recharge ??CO2 during hydrothermal circulation. Apparent temperatures of equilibration between the CH4 and the basalt-derived CO2 range from 640??C to 750??C. Small amounts of ethane (C2H6/CH4??? 0.9 ?? 10-3-2.2 ?? 10-3), propane, and butane detected in the samples may also have formed in the basalt. One sample of almost pure (95.5%) hydrothermal fluid contained a significant fraction, up to 63% and 74%, respectively, of the recharge Ar and N2. This suggests that the fluid has not undergone extensive vapor-liquid phase separation. -Authors

  16. Crystalline hydroxyapatite coatings synthesized under hydrothermal conditions on modified titanium substrates.

    PubMed

    Suchanek, Katarzyna; Bartkowiak, Amanda; Gdowik, Agnieszka; Perzanowski, Marcin; Kąc, Sławomir; Szaraniec, Barbara; Suchanek, Mateusz; Marszałek, Marta

    2015-06-01

    Hydroxyapatite coatings were successfully produced on modified titanium substrates via hydrothermal synthesis in a Ca(EDTA)(2-) and (NH4)2HPO4 solution. The morphology of modified titanium substrates as well as hydroxyapatite coatings was studied using scanning electron microcopy and phase identification by X-ray diffraction, and Raman and FTIR spectroscopy. The results show that the nucleation and growth of hydroxyapatite needle-like crystals with hexagonal symmetry occurred only on titanium substrates both chemically and thermally treated. No hydroxyapatite phase was detected on only acid etched Ti metal. This finding demonstrates that only a particular titanium surface treatment can effectively induce the apatite nucleation under hydrothermal conditions.

  17. Dynamics of the Yellowstone hydrothermal system

    USGS Publications Warehouse

    Hurwitz, Shaul; Lowenstern, Jacob B.

    2014-01-01

    The Yellowstone Plateau Volcanic Field is characterized by extensive seismicity, episodes of uplift and subsidence, and a hydrothermal system that comprises more than 10,000 thermal features, including geysers, fumaroles, mud pots, thermal springs, and hydrothermal explosion craters. The diverse chemical and isotopic compositions of waters and gases derive from mantle, crustal, and meteoric sources and extensive water-gas-rock interaction at variable pressures and temperatures. The thermal features are host to all domains of life that utilize diverse inorganic sources of energy for metabolism. The unique and exceptional features of the hydrothermal system have attracted numerous researchers to Yellowstone beginning with the Washburn and Hayden expeditions in the 1870s. Since a seminal review published a quarter of a century ago, research in many fields has greatly advanced our understanding of the many coupled processes operating in and on the hydrothermal system. Specific advances include more refined geophysical images of the magmatic system, better constraints on the time scale of magmatic processes, characterization of fluid sources and water-rock interactions, quantitative estimates of heat and magmatic volatile fluxes, discovering and quantifying the role of thermophile microorganisms in the geochemical cycle, defining the chronology of hydrothermal explosions and their relation to glacial cycles, defining possible links between hydrothermal activity, deformation, and seismicity; quantifying geyser dynamics; and the discovery of extensive hydrothermal activity in Yellowstone Lake. Discussion of these many advances forms the basis of this review.

  18. Tungsten enriched in submarine hydrothermal fluids

    NASA Astrophysics Data System (ADS)

    Kishida, Koichi; Sohrin, Yoshiki; Okamura, Kei; Ishibashi, Jun-ichiro

    2004-06-01

    Here we report the first data for W in hydrothermal vent fluids in the deep oceans. Vented hydrothermal fluids were collected from the Kairei Field, a mid ocean ridge hydrothermal field at the Rodriguez Triple Junction, Central Indian Ridge, and from arc-backarc hydrothermal systems at the Suiyo Seamount in the Izu-Bonin Arc, North Pacific Ocean and at the Hatoma and Yonaguni Knolls in the Okinawa Trough, East China Sea. While the dissolved W concentration in hydrothermal fluids linearly increased with a decrease in the Mg concentration for each system, the W concentration in endmember fluids was very different. It was 0.21 nmol/kg at the Kairei Field, 15 nmol/kg at the Suiyo Seamount, and 123 nmol/kg at the Hatoma Knoll, which was 4 orders of magnitude above the ambient level in seawater. The W concentration was not a simple function of Cl, alkalinity, B, and NH 4. The hydrothermal fields are efficiently enriched with W through reaction with fractionated calc-alkaline dacite and with terrigenous sediments. Although Mo is a chemical analogue of W in oxic seawater, the Mo concentration decreased in the hydrothermal fluids to 2-7 nmol/kg probably due to precipitation of Mo sulfide.

  19. Arctic Ocean: hydrothermal activity on Gakkel Ridge.

    PubMed

    Jean-Baptiste, Philippe; Fourré, Elise

    2004-03-01

    In the hydrothermal circulation at mid-ocean ridges, sea water penetrates the fractured crust, becomes heated by its proximity to the hot magma, and returns to the sea floor as hot fluids enriched in various chemical elements. In contradiction to earlier results that predict diminishing hydrothermal activity with decreasing spreading rate, a survey of the ultra-slowly spreading Gakkel Ridge (Arctic Ocean) by Edmonds et al. and Michael et al. suggests that, instead of being rare, the hydrothermal activity is abundant--exceeding by at least a factor of two to three what would be expected by extrapolation from observation on faster spreading ridges. Here we use helium-3 (3He), a hydrothermal tracer, to show that this abundance of venting sites does not translate, as would be expected, into an anomalous hydrothermal 3He output from the ridge. Because of the wide implications of the submarine hydrothermal processes for mantle heat and mass fluxes to the ocean, these conflicting results call for clarification of the link between hydrothermal activity and crustal production at mid-ocean ridges.

  20. Hydrothermal Occurrences in Gusev Crater

    NASA Astrophysics Data System (ADS)

    Ruff, S. W.; Farmer, J. D.; Milliken, R.; Mills, V. W.; Shock, E.

    2011-12-01

    Exploration of the Gusev crater landing site by the Spirit rover has revealed for the first time, in situ evidence of hydrothermal activity on Mars. Most compelling are eroded outcrops of opaline silica found adjacent to "Home Plate" [1], an eroded stack of volcaniclastic deposits stratigraphically overlain by a vesicular basalt unit [2]. Recent work [3] demonstrates that the silica outcrops occur in a stratiform unit that possibly surrounds Home Plate. The outcrops are dominated by opal-A with no evidence for diagenesis to other silica phases. No other hydrous or alteration phases have been identified within the outcrops; most notable is a lack of sulfur phases. The outcrops have porous and in some cases, brecciated microtextures. Taken together, these observations support the interpretation that the opaline silica outcrops were produced in a hot spring or perhaps geyser environment. In this context, they are silica sinter deposits precipitated from silica-rich hydrothermal fluids, possibly related to the volcanism that produced the Home Plate volcanic rocks. On Earth, debris aprons in which sinter is brecciated, reworked, and cemented, are common features of hot springs and geysers and are good analogs for the Martian deposits. An alternative hypothesis is that the silica resulted from acid-sulfate leaching of precursor rocks by fumarolic steam condensates. But stratigraphic, textural, and chemical observations tend to diminish this possibility [3]. We are conducting extensive laboratory and field investigations of silica from both hot spring/geyser and fumarole environments to understand the full range of mineralogical, chemical, textural, and morphological variations that accompany its production, in order to shed more light on the Home Plate occurrence. The recent discovery of abundant Mg-Fe carbonate (16-34 wt%) in outcrops named Comanche provides possible evidence for additional hydrothermal activity in Gusev [4]. However, the carbonate is hosted by olivine

  1. Seawater bicarbonate removal during hydrothermal circulation

    NASA Astrophysics Data System (ADS)

    Proskurowski, G. K.; Seewald, J.; Sylva, S. P.; Reeves, E.; Lilley, M. D.

    2013-12-01

    High temperature fluids sampled at hydrothermal vents represent a complex alteration product of water-rock reactions on a multi-component mixture of source fluids. Sources to high-temperature hydrothermal samples include the 'original' seawater present in the recharge limb of circulation, magmatically influenced fluids added at depth as well as any seawater entrained during sampling. High-temperature hydrothermal fluids are typically enriched in magmatic volatiles, with CO2 the dominant species, characterized by concentrations of 10's-100's of mmol/kg (1, 2). Typically, the high concentration of CO2 relative to background seawater bicarbonate concentrations (~2.3 mmol/kg) obscures a full analysis of the fate of seawater bicarbonate during high-temperature hydrothermal circulation. Here we present data from a suite of samples collected over the past 15 years from high-temperature hydrothermal vents at 9N, Endeavour, Lau Basin, and the MAR that have endmember CO2 concentrations less than 10 mmol/kg. Using stable and radiocarbon isotope measurements these samples provide a unique opportunity to examine the balance between 'original' seawater bicarbonate and CO2 added from magmatic sources. Multiple lines of evidence from multiple hydrothermal settings consistently points to the removal of ~80% of the 'original' 2.3 mmol/kg seawater bicarbonate. Assuming that this removal occurs in the low-temperature, 'recharge' limb of hydrothermal circulation, this removal process is widely occurring and has important contributions to the global carbon cycle over geologic time. 1. Lilley MD, Butterfield DA, Lupton JE, & Olson EJ (2003) Magmatic events can produce rapid changes in hydrothermal vent chemistry. Nature 422(6934):878-881. 2. Seewald J, Cruse A, & Saccocia P (2003) Aqueous volatiles in hydrothermal fluids from the Main Endeavour Field, northern Juan de Fuca Ridge: temporal variability following earthquake activity. Earth and Planetary Science Letters 216(4):575-590.

  2. Low density solvent based dispersive liquid-liquid microextraction with gas chromatography-electron capture detection for the determination of cypermethrin in tissues and blood of cypermethrin treated rats.

    PubMed

    Mudiam, Mohana Krishna Reddy; Jain, Rajeev; Maurya, Shailendra Kumar; Khan, Haider A; Bandyopadhyay, Sanghamitra; Murthy, R C

    2012-05-01

    A simple and rapid method to determine the cypermethrin (CYP) insecticide in rat tissues (kidney, liver and brain) and blood has been developed for the first time using low density solvent-dispersive liquid-liquid microextraction (LDS-DLLME) followed by gas chromatography-electron capture detector (GC-ECD) analysis. Initially, tissue samples containing CYP were homoginized in acetone. Subsequently, homogenate was mixed with n-hexane (extraction solvent) and the mixture was rapidly injected into water. The upper n-hexane layer was collected in a separate microtube and injected into GC-ECD for analysis. Blood samples were diluted with ultrapure water and subjected to DLLME through similar procedure. Parameters such as type and volume of disperser and extraction solvent, salting out effect and extraction time, which can affect the extraction efficiency of DLLME, were optimized. Method was validated by investigating linearity, precision, recovery, limit of detection (LOD) and quantification (LOQ). LODs in tissue were in the range of 0.043-0.314 ng mg(-1) and for blood it was 8.6 ng mL(-1) with a signal to noise ratio of 3:1. LOQs in tissue were in the range of 0.143-1.03 ng mg(-1) and for blood it was 28.3 ng mL(-1) with a signal to noise ratio of 10:1. Mean recoveries of CYP at three different concentation levels in all the matrices were found to be in the range of 81.6-103.67%. The results show that, LDS-DLLME coupled with GC-ECD offers a simple, rapid and efficient technique for extraction and determination of CYP in rat tissues and blood samples, which in turn would be useful for toxicological studies of CYP.

  3. A facile vapor-phase hydrothermal method for direct growth of titanate nanotubes on a titanium substrate via a distinctive nanosheet roll-up mechanism.

    PubMed

    Liu, Porun; Zhang, Haimin; Liu, Hongwei; Wang, Yun; Yao, Xiangdong; Zhu, Guangshan; Zhang, Shanqing; Zhao, Huijun

    2011-11-30

    We present a facile vapor-phase hydrothermal approach for direct growth of vertically aligned titanate nanotubes on a titanium foil substrate. The resultant nanotubes display external diameters of 50-80 nm and walls with an average thickness of 10 nm that consist of more than 10 titanate layers. This is in strong contrast to the titanate nanotubes obtained from alkaline liquid-phase hydrothermal methods, which are generally smaller than 12 nm in external diameter and have walls consisting of less than five titanate layers. Importantly, the investigation confirmed that under vapor-phase hydrothermal conditions, the nanotubes were formed via a distinctive nanosheet roll-up mechanism that differs remarkably from those of conventional liquid-phase hydrothermal processes. For the first time, a coaxial circular cylinder crystal structure of the resultant nanotubes was confirmed. PMID:22035232

  4. Multivariate curve resolution modeling of liquid chromatography-mass spectrometry data in a comparative study of the different endogenous metabolites behavior in two tomato cultivars treated with carbofuran pesticide.

    PubMed

    Siano, Gabriel G; Pérez, Isidro Sánchez; García, María D Gil; Galera, María Martínez; Goicoechea, Héctor C

    2011-07-15

    A metabonomic study based on the application of multivariate curve resolution and alternating least squares (MCR-ALS) to three-way data sets obtained by liquid chromatography coupled to mass spectrometry detection (LC-MS) was carried out for Rambo and Raf tomato cultivars treated with carbofuran pesticide. Samples were picked up during a 21 days period after treatment and analyzed by LC-MS in scan mode, along with the corresponding blank samples. Then, MCR-ALS was applied to the three-way data sets using column wise augmented matrices, and the evolutionary profiles as a function of the time after treatment were estimated for the metabolites present in both cultivars, as well as their corresponding pure spectra estimations. A comparative study using those estimations showed that some of these metabolites followed different behavior for the different cultivars after treatment. Since all treated and untreated Rambo and Raf samples were picked up according to the same sampling protocol and in a similar state of maturation, any difference in the behavior between profiles can be interpreted as an effect due to the presence of pesticide and to the kind of cultivar. Based on this hypothesis, several PLS-DA approaches were tested to check if it would be possible to classify samples by using the metabolites MCR estimations. Results showed that PLS-DA models for classification of treated or non-treated (blank) samples were the best ones obtained (98.44% of correct classifications for the validation set), which supports the stress effects related to carbofuran treatment. In addition, excellent discrimination among the four groups could be attained (89.06% of correct classifications for the validation set).

  5. What Defines a Separate Hydrothermal System

    SciTech Connect

    Lawless, J.V.; Bogie, I.; Bignall, G.

    1995-01-01

    Separate hydrothermal systems can be defined in a variety of ways. Criteria which have been applied include separation of heat source, upflow, economic resource and geophysical anomaly. Alternatively, connections have been defined by the effects of withdrawal of economically useful fluid and subsidence, effects of reinjection, changes in thermal features, or by a hydrological connection of groundwaters. It is proposed here that: ''A separate hydrothermal system is one that is fed by a separate convective upflow of fluid, at a depth above the brittle-ductile transition for the host rocks, while acknowledging that separate hydrothermal systems can be hydrologically interconnected at shallower levels''.

  6. Catastrophic volcanic collapse: relation to hydrothermal processes.

    PubMed

    López, D L; Williams, S N

    1993-06-18

    Catastrophic volcanic collapse, without precursory magmatic activity, is characteristic of many volcanic disasters. The extent and locations of hydrothermal discharges at Nevado del Ruiz volcano, Colombia, suggest that at many volcanoes collapse may result from the interactions between hydrothermal fluids and the volcanic edifice. Rock dissolution and hydrothermal mineral alteration, combined with physical triggers such as earth-quakes, can produce volcanic collapse. Hot spring water compositions, residence times, and flow paths through faults were used to model potential collapse at Ruiz. Caldera dimensions, deposits, and alteration mineral volumes are consistent with parameters observed at other volcanoes.

  7. Treating separated liquid dairy manure derived from mesophilic anaerobic digester effluent to reduce indicator pathogens and Salmonella concentrations for use as organic fertilizer.

    PubMed

    Collins, Elizabeth W; Ogejo, Jactone A; Krometis, Leigh Anne H

    2015-01-01

    Dairy manure has much potential for use as an organic fertilizer in the United States. However, the levels of indicator organisms and pathogens in dairy manure can be ten times higher than stipulated use guidelines by the National Organic Standards Board (NOSB) even after undergoing anaerobic digestion at mesophilic temperatures. The objective of this study was to identify pasteurization temperatures and treatment durations to reduce fecal coliforms, E. coli, and Salmonella concentrations in separated liquid dairy manure (SLDM) of a mesophilic anaerobic digester effluent to levels sufficient for use as an organic fertilizer. Samples of SLDM were pasteurized at 70, 75, and 80°C for durations of 0 to 120 min. Fecal coliforms, E. coli, and Salmonella concentrations were assessed via culture-based techniques. All of the tested pasteurization temperatures and duration combinations reduced microbial concentrations to levels below the NOSB guidelines. The fecal coliforms and E. coli reductions ranged 2from 0.76 to 1.34 logs, while Salmonella concentrations were reduced by more than 99% at all the pasteurization temperatures and active treatment durations.

  8. Online solid-phase extraction-liquid chromatography-electrospray-tandem mass spectrometry determination of multiple classes of antibiotics in environmental and treated waters.

    PubMed

    Panditi, Venkata R; Batchu, Sudha Rani; Gardinali, Piero R

    2013-07-01

    An online solid-phase extraction and liquid chromatography in combination with tandem mass spectrometry method was developed for the simultaneous determination of 31 antibiotics in drinking water, surface water and reclaimed waters. The developed methodology requires small sample volume (10 mL), very little sample preparation and total sample run time was 20 min. An Ion Max API heated electrospray ionization source operated in the positive mode with two selected reaction monitoring transitions was used per antibiotic for positive identity and quantification performed by the internal standard approach, to correct for matrix effects and any losses in the online extraction step. Method detection limits were in the range of 1.2-9.7, 2.2-15, 5.5-63 ng/L in drinking water, surface water and reclaimed waters, respectively. The method accuracy in matrix spiked samples ranged from 50-150% for the studied antibiotics. The applicability of the method was demonstrated using various environmental and reclaimed water matrices. Erythromycin was detected in more than 85% of the samples in all matrices (28-414, n.d.-199, n.d.-66 ng/L in reclaimed, river and drinking waters respectively). The other frequently detected antibiotics in reclaimed waters were nalidixic acid, clarithromycin, azithromycin, trimethoprim, and sulfamethoxazole.

  9. QUANTITATIVE ANALYSIS OF THE LASSEN HYDROTHERMAL SYSTEM, NORTH CENTRAL CALIFORNIA.

    USGS Publications Warehouse

    Ingebritsen, S.E.; Sorey, M.L.

    1985-01-01

    Our conceptual model of the Lassen system is termed a liquid-dominated hydrothermal system with a parasitic vapor-dominated zone. The essential feature of this model is that steam and steam-heated discharge at relatively high altitudes in Lassen Volcanic National Park (LVNP) and liquid discharge with high chloride concentrations at relatively low altitudes outside LVNP are both fed by an upflow of high-enthalpy two-phase fluid within the Park. Liquid flows laterally away from the upflow area toward the areas of high-chloride discharge, and steam rises through a vapor-dominated zone to feed the steam and steam-heated features. Numerical simulations show that several conditions are necessary for the development of this type of system, including (1) large-scale topographic relief; (2) an initial period of convective heating within an upflow zone followed by (3) a change in hydrologic or geologic conditions that initiates drainage of liquid from portions of the upflow zone; and (4) low-permeability barriers that inhibit the movement of cold water into the vapor zone. Refs.

  10. Validation and uncertainty estimation of a multiresidue method for pharmaceuticals in surface and treated waters by liquid chromatography-tandem mass spectrometry.

    PubMed

    Boleda, Ma Rosa; Galceran, Ma Teresa; Ventura, Francesc

    2013-04-19

    The estimation of measurement uncertainty associated with quantitative results is essential to assure the reliability of analytical methods and mandatory when a laboratory implements ISO standard 17025. In this work, a quantitative multi-residue method based on solid-phase extraction (SPE) and ultra-performance liquid chromatography tandem mass spectrometry detection (LC-MS/MS) has been developed and validated for the analysis of 53 pharmaceuticals (analgesics, anti-inflammatories, antibiotics, lipid regulating agents, cholesterol lowering stating agents, gastric drugs, X-ray, and miscellaneous compounds such as sildenafil, prednisone, triclosan, chlorhexidine and miconazole) in surface and drinking waters. A full validation of the method, according to ISO standard 17025 procedure, was performed. Linearity (0.01-250 ng/L range), intra-day precision (3-19%RSD in surface water and 2-19%RSD in drinking water) and inter-day precision (3-16%RSD in surface water and 1-18%RSD in drinking water), matrix effects (low matrix effects were observed for 50% of compounds in both matrices), limits of quantification (0.2-40 ng/L in surface water and 0.2-30 ng/L in drinking water) were calculated. The recoveries at 100 ng/L were >80% for 72% and 79% of the target compounds in surface and drinking waters, respectively. The information obtained from the full method validation has been used to estimate the expanded uncertainty and the uncertainties contributions of the different individual steps of the method for the determination of pharmaceuticals at trace levels in waters. Expanded relative uncertainties ranged from 6% to 23% being the uncertainty associated with reproducibility the main contribution. PMID:23510957

  11. Lipid Adaptation of Shrimp Rimicaris exoculata in Hydrothermal Vent.

    PubMed

    Zhu, Si; Ye, Mengwei; Yan, Xiaojun; Zhou, Yadong; Wang, Chunsheng; Xu, Jilin

    2015-12-01

    The shrimp Rimicaris exoculata is the most abundant species in hydrothermal vents. Lipids, the component of membranes, play an important role in maintaining their function normally in such extreme environments. In order to understand the lipid adaptation of R. exoculata (HV shrimp) to hydrothermal vents, we compared its lipid profile with the coastal shrimp Litopenaeus vannamei (EZ shrimp) which lives in the euphotic zone, using ultra performance liquid chromatography electrospray ionization-quadrupole time-of-flight mass spectrometry. As a result, the following lipid adaptation can be observed. (1) The proportion of 16:1 and 18:1, and non-methylene interrupted fatty acid (48.9 and 6.2 %) in HV shrimp was higher than that in EZ shrimp (12.7 and 0 %). While highly-unsaturated fatty acids were only present in the EZ shrimp. (2) Ceramide and sphingomyelin in the HV shrimp were enriched in d14:1 long chain base (96.5 and 100 %) and unsaturated fatty acids (67.1 and 57.7 %). While in the EZ shrimp, ceramide and sphingomyelin had the tendency to contain d16:1 long chain base (68.7 and 75 %) and saturated fatty acids (100 and 100 %). (3) Triacylglycerol content (1.998 ± 0.005 nmol/mg) in the HV shrimp was higher than that in the EZ shrimp (0.092 ± 0.005 nmol/mg). (4) Phosphatidylinositol and diacylglycerol containing highly-unsaturated fatty acids were absent from the HV shrimp. (5) Lysophosphatidylcholine and lysophosphatidylethanolamine were rarely detected in the HV shrimp. A possible reason for such differences was the result of food resources and inhabiting environments. Therefore, these lipid classes mentioned above may be the biomarkers to compare the organisms from different environments, which will be benefit for the further exploitation of the hydrothermal environment.

  12. Lipid Adaptation of Shrimp Rimicaris exoculata in Hydrothermal Vent.

    PubMed

    Zhu, Si; Ye, Mengwei; Yan, Xiaojun; Zhou, Yadong; Wang, Chunsheng; Xu, Jilin

    2015-12-01

    The shrimp Rimicaris exoculata is the most abundant species in hydrothermal vents. Lipids, the component of membranes, play an important role in maintaining their function normally in such extreme environments. In order to understand the lipid adaptation of R. exoculata (HV shrimp) to hydrothermal vents, we compared its lipid profile with the coastal shrimp Litopenaeus vannamei (EZ shrimp) which lives in the euphotic zone, using ultra performance liquid chromatography electrospray ionization-quadrupole time-of-flight mass spectrometry. As a result, the following lipid adaptation can be observed. (1) The proportion of 16:1 and 18:1, and non-methylene interrupted fatty acid (48.9 and 6.2 %) in HV shrimp was higher than that in EZ shrimp (12.7 and 0 %). While highly-unsaturated fatty acids were only present in the EZ shrimp. (2) Ceramide and sphingomyelin in the HV shrimp were enriched in d14:1 long chain base (96.5 and 100 %) and unsaturated fatty acids (67.1 and 57.7 %). While in the EZ shrimp, ceramide and sphingomyelin had the tendency to contain d16:1 long chain base (68.7 and 75 %) and saturated fatty acids (100 and 100 %). (3) Triacylglycerol content (1.998 ± 0.005 nmol/mg) in the HV shrimp was higher than that in the EZ shrimp (0.092 ± 0.005 nmol/mg). (4) Phosphatidylinositol and diacylglycerol containing highly-unsaturated fatty acids were absent from the HV shrimp. (5) Lysophosphatidylcholine and lysophosphatidylethanolamine were rarely detected in the HV shrimp. A possible reason for such differences was the result of food resources and inhabiting environments. Therefore, these lipid classes mentioned above may be the biomarkers to compare the organisms from different environments, which will be benefit for the further exploitation of the hydrothermal environment. PMID:26475295

  13. Using noble gases measured in spring discharge to trace hydrothermal processes in the Norris Geyser Basin, Yellowstone National Park, U.S.A.

    USGS Publications Warehouse

    Gardner, W.P.; Susong, D.D.; Solomon, D.K.; Heasler, H.P.

    2010-01-01

    Dissolved noble gas concentrations in springs are used to investigate boiling of hydrothermal water and mixing of hydrothermal and shallow cool water in the Norris Geyser Basin area. Noble gas concentrations in water are modeled for single stage and continuous steam removal. Limitations on boiling using noble gas concentrations are then used to estimate the isotopic effect of boiling on hydrothermal water, allowing the isotopic composition of the parent hydrothermal water to be determined from that measured in spring. In neutral chloride springs of the Norris Geyser Basin, steam loss since the last addition of noble gas charged water is less than 30% of the total hydrothermal discharge, which results in an isotopic shift due to boiling of ?? 2.5% ??D. Noble gas concentrations in water rapidly and predictably change in dual phase systems, making them invaluable tracers of gas-liquid interaction in hydrothermal systems. By combining traditional tracers of hydrothermal flow such as deuterium with dissolved noble gas measurements, more complex hydrothermal processes can be interpreted. ?? 2010 Elsevier B.V.

  14. Hydrothermal treatment for inactivating some hygienic microbial indicators from food waste-amended animal feed.

    PubMed

    Jin, Yiying; Chen, Ting; Li, Huan

    2012-07-01

    To achieve the hygienic safety of food waste used as animal feed, a hydrothermal treatment process of 60-110 degrees C for 10-60 min was applied on the separated food waste from a university canteen. Based on the microbial analysis of raw waste, the inactivation of hygienic indicators of Staphylococcus aureus (SA), total coliform (TC), total aerobic plate counts (TPC), and molds and yeast (MY) were analyzed during the hydrothermal process. Results showed that indicators' concentrations were substantially reduced after hydrothermal treatment, with a greater reduction observed when the waste was treated with a higher temperature and pressure and a longer ramping time. The 110 degrees C hydrothermal treatment for 60 min was sufficient to disinfect food waste as animal feed from the viewpoint of hygienic safety. Results obtained so far indicate that hydrothermal treatment can significantly decrease microbial indicators' concentrations but does not lead to complete sterilization, because MY survived even after 60 min treatment at 110 degrees C. The information from the present study will contribute to the microbial risk control of food waste-amended animal feed, to cope with legislation on food or feed safety.

  15. Comprehensive monitoring and management of a long-term thermophilic CSTR treating coffee grounds, coffee liquid, milk waste, and municipal sludge.

    PubMed

    Shofie, Mohammad; Qiao, Wei; Li, Qian; Takayanagi, Kazuyuki; Li, Yu-You

    2015-09-01

    The CSTR process has previously not been successfully applied to treat coffee residues under thermophilic temperature and long term operation. In this experiment, the CSTR was fed with mixture substrate (TS ∼ 70 g/L) of coffee grounds, coffee wastewater, milk waste and municipal sludge and it was operated under 55 °C for 225 days. A steady state was achieved under HRT 30 days and OLR 4.0 kg-COD/m(3)/d. However, there was an 35 days inhibition with VFA accumulation (propionic acid 700-1900 mg/L) when doubling the OLR by shortening HRT to 15 days. But, an addition of microelements and sulfate (0.5 g/L) in feedstock increased reactor resilience and stability under high loading rate and propionic acid stress. Continuous monitoring of hydrogen in biogas indicated the imbalance of acetogenesis. The effectiveness of comprehensive parameters (total VFA, propionic acid, IA/PA, IA/TA and CH4 content) was proved to manage the thermophilic system.

  16. The targeted proteins in tumor cells treated with the α-lactalbumin-oleic acid complex examined by descriptive and quantitative liquid chromatography-tandem mass spectrometry.

    PubMed

    Fang, B; Zhang, M; Fan, X; Ren, F Z

    2016-08-01

    An α-lactalbumin-oleic acid (α-LA-OA) complex has exhibited selective antitumor activity in animal models and clinical trials. Although apoptosis and autophagy are activated and the functions of several organelles are disrupted in response to α-LA-OA, the detailed antitumor mechanism remains unclear. In this study, we used a novel technique, isobaric tags for relative and absolute quantitation, to analyze the proteome of tumor cells treated with α-LA-OA. We identified 112 differentially expressed proteins: 95 were upregulated to satisfy the metabolism of tumor cells; 17 were downregulated and targets of α-LA-OA. According to the differentially expressed proteins, α-LA-OA exerted its antitumor activity by disrupting cytoskeleton stability and cell motility, and by inhibiting DNA, lipid, and ATP synthesis, leading to cellular stress and activation of programmed cell death. This study provides a systematic evaluation of the antitumor activity of α-LA-OA, identifying its interacting targets and establishing the theoretical basis of α-LA-OA for use in cancer therapy. PMID:27236751

  17. Chemical environments of submarine hydrothermal systems

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.

    1992-01-01

    Perhaps because black-smoker chimneys make tremendous subjects for magazine covers, the proposal that submarine hydrothermal systems were involved in the origin of life has caused many investigators to focus on the eye-catching hydrothermal vents. In much the same way that tourists rush to watch the spectacular eruptions of Old Faithful geyser with little regard for the hydrology of the Yellowstone basin, attention is focused on the spectacular, high-temperature hydrothermal vents to the near exclusion of the enormous underlying hydrothermal systems. Nevertheless, the magnitude and complexity of geologic structures, heat flow, and hydrologic parameters which characterize the geyser basins at Yellowstone also characterize submarine hydrothermal systems. However, in the submarine systems the scale can be considerably more vast. Like Old Faithful, submarine hydrothermal vents have a spectacular quality, but they are only one fascinating aspect of enormous geologic systems operating at seafloor spreading centers throughout all of the ocean basins. A critical study of the possible role of hydrothermal processes in the origin of life should include the full spectrum of probable environments. The goals of this chapter are to synthesize diverse information about the inorganic geochemistry of submarine hydrothermal systems, assemble a description of the fundamental physical and chemical attributes of these systems, and consider the implications of high-temperature, fluid-driven processes for organic synthesis. Information about submarine hydrothermal systems comes from many directions. Measurements made directly on venting fluids provide useful, but remarkably limited, clues about processes operating at depth. The oceanic crust has been drilled to approximately 2.0 km depth providing many other pieces of information, but drilling technology has not allowed the bore holes and core samples to reach the maximum depths to which aqueous fluids circulate in oceanic crust. Such

  18. Rare earth element systematics in hydrothermal fluids

    SciTech Connect

    Michard, A. )

    1989-03-01

    Rare earth element concentrations have been measured in hydrothermal solutions from geothermal fields in Italy, Dominica, Valles Caldera, Salton Sea and the Mid-Atlantic Ridge. The measured abundances show that hydrothermal activity is not expected to affect the REE balance of either continental or oceanic rocks. The REE enrichment of the solutions increases when the pH decreases. High-temperature solutions (> 230{degree}C) percolating through different rock types may show similar REE patterns.

  19. Hydrothermal industrialization: direct heat development. Final report

    SciTech Connect

    Not Available

    1982-05-01

    A description of hydrothermal resources suitable for direct applications, their associated temperatures, geographic distribution and developable capacity are given. An overview of the hydrothermal direct-heat development infrastructure is presented. Development activity is highlighted by examining known and planned geothermal direct-use applications. Underlying assumptions and results for three studies conducted to determine direct-use market penetration of geothermal energy are discussed.

  20. Fabrication of hydroxyapatite and TiO 2 nanorods on microarc-oxidized titanium surface using hydrothermal treatment

    NASA Astrophysics Data System (ADS)

    Song, Ho-Jun; Kim, Ji-Woo; Kook, Min-Suk; Moon, Won-Jin; Park, Yeong-Joon

    2010-09-01

    AC-type microarc oxidation (MAO) and hydrothermal treatment techniques were used to enhance the bioactivity of commercially pure titanium (CP-Ti). The porous TiO 2 layer fabricated by the MAO treatment had a dominant anatase structure and contained Ca and P ions. The MAO-treated specimens were treated hydrothermally to form HAp crystallites on the titanium oxide layer in an alkaline aqueous solution (OH-solution) or phosphorous-containing alkaline solution (POH-solution). A small number of micro-sized hydroxyapatite (HAp) crystallites and a thin layer composed of nano-sized HAps were formed on the Ti-MAO-OH group treated hydrothermally in an OH-solution, whereas a large number of micro-sized HAp crystallites and dense anatase TiO 2 nanorods were formed on the Ti-MAO-POH group treated hydrothermally in a POH-solution. The layer of bone-like apatite that formed on the surface of the POH-treated sample after soaking in a modified simulated body fluid was thicker than that on the OH-treated samples.

  1. Topographic control of a dispersing hydrothermal plume

    NASA Astrophysics Data System (ADS)

    German, C. R.; Richards, K. J.; Rudnicki, M. D.; Lam, M. M.; Charlou, J. L.; Flame Scientific Party

    1998-03-01

    Deep-sea hydrothermal vents represent a major source of heat and chemicals to the oceans and support endemic chemosynthetic biological communities. To fully understand the impact of hydrothermal activity upon the oceans, however, requires investigation of both the physical and the biogeochemical processes which are active in hydrothermal plumes and which serve to determine the net hydrothermal flux to the oceans. We have recently conducted a detailed multidisciplinary study of the lateral dispersion of the hydrothermal plume emitted from the Rainbow vent site near 36°15'N, Mid-Atlantic Ridge. Combining velocity measurements from a lowered ADCP, optical back scatter measurements from a deep-tow CTD and methane measurements from bottle samples we are able, for the first time in the Atlantic, to trace a neutrally buoyant plume for a distance of over 50 km. The path of the plume is seen to be heavily controlled by the local topography with a general northeast movement of water. Both particle and methane concentrations decrease downstream over the length of the observed plume. The dataset provides an excellent opportunity to study the mixing and biogeochemical processes active in a hydrothermal plume and estimate fluxes of biogeochemical constituents.

  2. Simultaneous quantitation of polymyxin B1, polymyxin B2 and polymyxin B1-1 in human plasma and treated human urine using solid phase extraction and liquid chromatography-tandem mass spectrometry.

    PubMed

    Meng, Min; Wang, Laixin; Liu, Sherry; Jaber, Othman M; Gao, Lihong; Chevrette, Lynn; Reuschel, Scott

    2016-02-15

    Two liquid chromatographic-tandem mass spectrometric (LC-MS/MS) methods have been developed and validated for the quantitative determination of polymyxin B1, polymyxin B2 and polymyxin B1-1 concentrations in human plasma and treated urine. During method development, technical challenges such as the separation of structural isomers polymyxin B1and polymyxin B1-1 and nonspecific binding in urine samples were encountered and overcome. Two automated solid phase extraction methods were used to extract plasma samples (100μL) and urine samples (200μL) and the resulting extracts were analyzed using reversed phase LC-MS/MS with an electrospray (ESI) interface and selected reaction monitoring (SRM) in the positive ionization mode. Both methods were validated over a calibration curve range of 5.00-2000ng/mL with a linear regression and 1/x(2) weighting. The between-run relative standard deviation (%RSD) ranged from 4.5 to 9.5% for the plasma assay and from 1.1 to 7.1% for the urine assay. For the plasma assay, the between-run accuracy ranged from 100.5 to 115.2% of nominal at all QC concentrations including the LLOQ. For the urine assay, the between-run accuracy ranged from 92.0 to 106% of nominal at all QC concentrations including the LLOQ. The extraction recoveries for all polymyxins in both assays were between 54.0 and 64.2%. Long term matrix storage stability for all polymyxins was established at both -20°C and -70°C for up to 85 days in human plasma and for up to 55 days in treated human urine. Both assays were used for the measurement of polymyxin B1, polymyxin B2 and polymyxin B1-1 concentrations in human plasma and treated urine for the determination of bioequivalence and toxicokinetic parameters in clinical studies.

  3. Investigation on phase transformation mechanism of zeolite NaY under alkaline hydrothermal conditions

    SciTech Connect

    Li, Peng Ding, Tian Liu, Liping Xiong, Guang

    2013-12-15

    The phase transformation mechanism of zeolite NaY under alkaline hydrothermal conditions was investigated by UV Raman spectroscopy, X-ray diffraction, X-ray fluorescence and scanning electron microscopy techniques. The results revealed that the products and transformation rate are dependent on the alkalinities. All of the starting and resulting zeolites are constructed with the 4-ring and 6-ring secondary building units. The products have lower Si/Al ratio, higher framework density and smaller pore size, which are more stable under alkaline hydrothermal condition. During the phase transformation the fragments of faujasite are formed, then the fragments combine to form different zeolites depending on basicity. Zeolite NaY crystals are consumed as the reservoir for the transformation products during the recrystallization process. For the first time, a 4-membered ring intermediate was found at the early stage of the recrystallization process. A cooperative interaction of liquid and solid phases is required for inducing the phase transformation. - Graphical Abstract: Phase transformation of NaY zeolite under alkaline hydrothermal condition is achieved by the cooperative interaction of the liquid and solid phases. A 4-membered ring species is an intermediate for recrystallization process. Highlights: • The products and transformation rate are dependent on the alkalinity. • A 4-membered ring species is an intermediate for recrystallization process. • A cooperative interaction of liquid and solid phases is required.

  4. A simulation of the hydrothermal response to the Chesapeake Bay bolide impact

    USGS Publications Warehouse

    Sanford, W.E.

    2005-01-01

    Groundwater more saline than seawater has been discovered in the tsunami breccia of the Chesapeake Bay impact Crater. One hypothesis for the origin of this brine is that it may be a liquid residual following steam separation in a hydrothermal system that evolved following the impact. Initial scoping calculations have demonstrated that it is feasible such a residual brine could have remained in the crater for the 35 million years since impact. Numerical simulations have been conducted using the code HYDROTHERM to test whether or not conditions were suitable in the millennia following the impact for the development of a steam phase in the hydrothermal system. Hydraulic and thermal parameters were estimated for the bedrock underlying the crater and the tsunami breccia that fills the crater. Simulations at three different breccia permeabilities suggest that the type of hydrothermal system that might have developed would have been very sensitive to the permeability. A relatively low breccia permeability (1 ?? 10-16 m2) results in a system partitioned into a shallow water phase and a deeper superheated steam phase. A moderate breccia permeability (1 ?? 10-15 m2 ) results in a system with regionally extensive multiphase conditions. A relatively high breccia permeability (1 ?? 10-14 m2 ) results in a system dominated by warm-water convection cells. The permeability of the crater breccia could have had any of these values at given depths and times during the hydrothermal system evolution as the sediments compacted. The simulations were not able to take into account transient permeability conditions, or equations of state that account for the salt content of seawater. Results suggest, however, that it is likely that steam conditions existed at some time in the system following impact, providing additional evidence that is consistent with a hydrothermal origin for the crater brine. ?? Blackwell Publishing Ltd.

  5. Structure of two hydrothermal megaplumes

    SciTech Connect

    D`asaro, E.; Walker, S.; Baker, E. |

    1994-10-01

    The dynamic signatures of two megaplumes above the Juan de Fuca Ridge are analyzed. The chemical properties of these two lenslike masses of water were described by Baker at al. (1989) and clearly indicate that they were generated by massive and rapid ventings of hot hydrothermal fluid from the ridge. Both are nearly circular with radii of about 6.5 km. The isopycnals bow upward around these cores of anomalous water, leading to an anticyclonic circulation. A cyclogeostrophic balance gives maximum currents at the edge of the core of 0.11 m/s for the first megaplume (MP1) and 0.07 m/s for the second megaplume (MP2). Currents extend beyond the core to a radius of 12-15 km. The centers of the cores are in nearly solid body rotation with relative vorticities of -0.5f (MP2) and potential vorticity anomalies, expressed in units of equivalent relative vorticity, of -0.8f (MP1) and -0.6f (MP2), where f is the Coriolis frequency. The aspect ratio of each megaplume gives a Burger number of 0.22. In terms of these nondimensional numbers, the megaplumes are very similar to eddies of Mediterranean water found in the eastern Atlantic (meddies), despite their very different origin.

  6. Natural analogue of CO2 dispersion at deep-sea hydrothermal system

    NASA Astrophysics Data System (ADS)

    Shitashima, K.; Maeda, Y.; Ohsumi, T.

    2006-12-01

    CO2 ocean sequestration is being investigated as one of possible options to limit the accumulation of anthropogenic CO2 into the atmosphere. To investigate the appropriateness of CO2 ocean sequestration, the observations for dispersion behavior of sequestrated CO2 into the ocean and influence of a high CO2 environment upon the ocean including marine ecosystem are important. Hydrothermal vent fluids are highly enriched in CO2 and the CO2 rich fluids are released into the ocean as a hydrothermal plume. Especially, the emission of hydrothermal-related liquid CO2 from the sea floor at about 1500m depth was discovered at the Okinawa Trough and Mariana Trough. At these areas, it is considered that the liquid CO2 rises up to shallow depth as a CO2 droplet and that the rising CO2 droplet dissolves gradually in ambient seawater. Deep-sea hydrothermal systems are suitable for natural analogue of CO2 dispersion in the ocean. New cost-effective observation techniques to monitor the dispersion of CO2 were developed. The in-situ pH/pCO2 sensor is high precision in-situ measurement technology of pH and pCO2 in seawater. This sensor can detect precisely and rapidly the changes of pH and pCO2 derived from high CO2. The towing multi-layer monitoring system is observation technology of CO2 dispersion in the ocean. This system can observe the dispersion behavior of CO2 by towing several in-situ sensors and SSBL transponders in the high CO2 plume. The in-situ pH/pCO2 sensor is installed to each transponder of the towing multi-layer monitoring system and in-situ data can be monitored by sound communication in real time on board. We will report the results of an application of these observation techniques to the deep-sea hydrothermal system.

  7. Monitoring the hydrothermal system in Long Valley caldera, California

    USGS Publications Warehouse

    Farrar, C.D.; Sorey, M.L.

    1985-01-01

    An ongoing program to monitor the hydrothermal system in Long Valley for changes caused by volcanic or tectonic processes has produced considerable data on the water chemistry and discharge of springs and fluid temperatures and pressures in wells. Chemical and isotopic data collected under this program have greatly expanded the knowledge of chemical variability both in space and time. Although no chemical or isotopic changes in hot spring waters can be attributed directly to volcanic or tectonic processes, changes in hot spring chemistry that have been recorded probably relate to interactions between and variations in the quantity of liquid and gas discharged. Stable carbon isotope data are consistent with a carbon source either perform the mantle or from metamorphosed carbonate rocks. Continuous and periodic measurements of hot spring discharge at several sites show significant co seismic and a seismic changes since 1980.

  8. Hydrothermal liquefaction of Nannochloropsis oceanica in different solvents.

    PubMed

    Caporgno, M P; Pruvost, J; Legrand, J; Lepine, O; Tazerout, M; Bengoa, C

    2016-08-01

    Although the hydrothermal liquefaction is considered a promising technology for converting microalgae into liquid biofuels, there are still some disadvantages. This paper demonstrated that the bio-oil yield can be significantly improved by adding alcohols as co-solvents and carrying out the conversion at mild conditions (<250°C), but at the expense of a reduced bio-oil quality. By adding ethanol, the bio-oil yields obtained (up to ∼60%) were comparable to the yield obtained at severe operating conditions using only water as solvent (54±2% on average), but the quality of the bio-oil was lower. However, the main advantages of the process here described lie in the utilisation of wet microalgae (∼75% moisture) and alcohol concentrations which avoid both drying the microalgae and decreasing the amount of microalgae loaded in the reactor.

  9. Hydrothermal liquefaction of Nannochloropsis oceanica in different solvents.

    PubMed

    Caporgno, M P; Pruvost, J; Legrand, J; Lepine, O; Tazerout, M; Bengoa, C

    2016-08-01

    Although the hydrothermal liquefaction is considered a promising technology for converting microalgae into liquid biofuels, there are still some disadvantages. This paper demonstrated that the bio-oil yield can be significantly improved by adding alcohols as co-solvents and carrying out the conversion at mild conditions (<250°C), but at the expense of a reduced bio-oil quality. By adding ethanol, the bio-oil yields obtained (up to ∼60%) were comparable to the yield obtained at severe operating conditions using only water as solvent (54±2% on average), but the quality of the bio-oil was lower. However, the main advantages of the process here described lie in the utilisation of wet microalgae (∼75% moisture) and alcohol concentrations which avoid both drying the microalgae and decreasing the amount of microalgae loaded in the reactor. PMID:27155795

  10. Numerical Simulations of the Hydrothermal System at Lassen Volcanic National Park

    SciTech Connect

    Sorey, Michael L.; Ingebritsen, Steven E.

    1983-12-15

    The hydrothermal system in the vicinity of Lassen Volcanic National Park contains a central region of fluid upflow in which steam and liquid phases separate, with steam rising through a parasitic vapor-dominated zone and liquid flowing laterally toward areas of hot spring discharge south of the Park. A simplified numerical model was used to simulate the 10,000-20,000 year evolution of this system and to show that under certain circumstances fluid withdrawal from hot-water reservoirs south of the Park could significantly alter the discharge of steam from thermal areas within the Park.

  11. Numerical Simulation of Hydrothermal Convection in Chondritic Parent Bodies

    NASA Astrophysics Data System (ADS)

    Schubert, G.; Travis, B. J.

    2004-11-01

    Chondritic meteorites are so named because they nearly all contain chondrules - small spherules of olivine and pyroxene that condensed and crystallized in the solar nebula and then combined with other material to form a matrix. Their parent bodies did not differentiate, i.e., form a crust and a core. Carbonaceous chondrites (CCs) derived from undifferentiated icy planetesimals. CCs exhibit liquid water-rock interactions. CCs contain small but significant amounts of radiogenic elements (e.g., 26Al), sufficient to warm up an initially cold planetesimal. A warmed-up phase could last millions of years. During the warmed-up phase, liquid water will form, and could evolve into a hydrothermal convective flow. Flowing water will affect the evolution of minerals. We report on results of a numerical study of the thermal evolution of CCs, considering the major factors that control heating history and possible flow, namely: permeability, radiogenic element content, and planetesimal radius. We determine the time sequence of thermal processes, length of time for a convective phase and patterns of flow, amount of fluid flow throughout the planetesimals, and sensitivity of evolution to primary parameters. We use the MAGHNUM code to simulate 3-D dynamic freezing and thawing and flow of water in a self-gravitating, permeable spherical body. Governing equations are Darcy's law, mass conservation, energy conservation, and the equation of state for water, ice and vapor mixtures. We have simulated the evolution of heating, melting of ice, subsequent flow and eventual re-freezing for several examples of carbonaceous chondrite planetesimals. We have demonstrated that hydrothermal convection should occur for a range of parameter values and would last for several millions of years. Roughly half the interior of simulated planetesimals experience water fluxes of 100--200 pore volumes. High pore volume flux facilitates extensive chemical reactions.

  12. Elimination of cutting oil wastes by promoted hydrothermal oxidation.

    PubMed

    Portela, J R; López, J; Nebot, E; Martínez de la Ossa, E

    2001-11-16

    Cutting oils are emulsionable fluids widely used in metalworking processes. Their composition is normally oil, water, and additives (fatty acids, surfactants, biocides, etc.) generating a toxic waste after a long use. Generally, it is a waste too dilute to be incinerated and it is difficult to treat biologically. Other conventional treatment methods currently used are not satisfactory from the environmental point of view. Wet air oxidation (WAO) and supercritical water oxidation (SCWO) are two forms of hydrothermal oxidation that have been proved to be effective processes to treat a wide variety of industrial wastes, but hardly tested for oily wastes. In the case of refractory wastes, WAO process is not efficient enough due to the moderate temperatures used. SCWO is a more powerful process since operating temperatures are usually around 600 degrees C, but the use of severe conditions leads to major disadvantages in the commercialization of the technology. In order to enhance WAO and SCWO efficiency at mild conditions, the use of free radical promoters has been studied in this work. Both normal and promoted hydrothermal oxidation have been tested to treat cutting oil wastes in a continuous flow system operating at 300-500 degrees C. Hydrogen peroxide has been used both as a source of oxygen and as a source of free radicals by introducing it into the reactor with or without previous thermal decomposition, respectively. Organic material is easily oxidized in both cases, obtaining more than 90% TOC reduction in less than 10s at 500 degrees C. At lower temperatures, the use of promoters clearly enhances the oxidation process. Activation energies have been estimated for normal and promoted oxidation processes.

  13. Hydrothermal mineralization at seafloor spreading centers

    NASA Astrophysics Data System (ADS)

    Rona, Peter A.

    1984-01-01

    The recent recognition that metallic mineral deposits are concentrated by hydrothermal processes at seafloor spreading centers constitutes a scientific breakthrough that opens active sites at seafloor spreading centers as natural laboratories to investigate ore-forming processes of such economically useful deposits as massive sulfides in volcanogenic rocks on land, and that enhances the metallic mineral potential of oceanic crust covering two-thirds of the Earth both beneath ocean basins and exposed on land in ophiolite belts. This paper reviews our knowledge of processes of hydrothermal mineralization and the occurrence and distribution of hydrothermal mineral deposits at the global oceanic ridge-rift system. Sub-seafloor hydrothermal convection involving circulation of seawater through fractured rocks of oceanic crust driven by heat supplied by generation of new lithosphere is nearly ubiquitous at seafloor spreading centers. However, ore-forming hydrothermal systems are extremely localized where conditions of anomalously high thermal gradients and permeability increase hydrothermal activity from the ubiquitous low-intensity background level (⩽ 200°C) to high-intensity characterized by high temperatures ( > 200-c.400°C), and a rate and volume of flow sufficient to sustain chemical reactions that produce acid, reducing, metal-rich primary hydrothermal solutions. A series of mineral phases with sulfides and oxides as high- and low-temperature end members, respectively, are precipitated along the upwelling limb and in the discharge zone of single-phase systems as a function of increasing admixture of normal seawater. The occurrence of hydrothermal mineral deposits is considered in terms of spatial and temporal frames of reference. Spatial frames of reference comprise structural features along-axis (linear sections that are the loci of seafloor spreading alternating with transform faults) and perpendicular to axis (axial zone of volcanic extrusion and marginal

  14. Marine diagenesis of hydrothermal sulfide

    SciTech Connect

    Moammar, M.O.

    1985-01-01

    An attempt is made to discuss the artificial and natural oxidation and hydrolysis of hydrothermal sulfide upon interaction with normal seawater. Synthetic and natural ferrosphalerite particles used in kinetic oxidation and hydrolysis studies in seawater develop dense, crystalline coatings consisting of ordered and ferrimagnetic delta-(Fe, Zn)OOH. Due to the formation of this reactive diffusion barrier, the release of Zn into solution decreases rapidly, and sulfide oxidation is reduced to a low rate determined by the diffusion of oxygen through the oxyhydroxide film. This also acts as an efficient solvent for ions such as Zn/sup 2 +/, Ca/sup 2 +/, and possibly Cd/sup 2 +/, which contribute to the stabilization of the delta-FeOOH structure. The oxidation of sulfide occurs in many seafloor spreading areas, such as 21/sup 0/N on the East Pacific Ridge. In these areas the old surface of the sulfide chimneys are found to be covered by an orange stain, and sediment near the base of nonactive vents is also found to consist of what has been referred to as amorphous iron oxide and hydroxide. This thesis also discusses the exceedingly low solubility of zinc in seawater, from delta-(Fe, Zn)OOH and the analogous phase (zinc-ferrihydroxide) and the zinc exchange minerals, 10-A manganate and montmorillonite. The concentrations of all four are of the same magnitude (16, 36.4, and 12 nM, respectively) as the zinc concentration in deep ocean water (approx. 10 nM), which suggests that manganates and montmorillonite with iron oxyhydroxides control zinc concentration in the deep ocean.

  15. Peptide synthesis in early earth hydrothermal systems

    USGS Publications Warehouse

    Lemke, K.H.; Rosenbauer, R.J.; Bird, D.K.

    2009-01-01

    We report here results from experiments and thermodynamic calculations that demonstrate a rapid, temperature-enhanced synthesis of oligopeptides from the condensation of aqueous glycine. Experiments were conducted in custom-made hydrothermal reactors, and organic compounds were characterized with ultraviolet-visible procedures. A comparison of peptide yields at 260??C with those obtained at more moderate temperatures (160??C) gives evidence of a significant (13 kJ ?? mol-1) exergonic shift. In contrast to previous hydrothermal studies, we demonstrate that peptide synthesis is favored in hydrothermal fluids and that rates of peptide hydrolysis are controlled by the stability of the parent amino acid, with a critical dependence on reactor surface composition. From our study, we predict that rapid recycling of product peptides from cool into near-supercritical fluids in mid-ocean ridge hydrothermal systems will enhance peptide chain elongation. It is anticipated that the abundant hydrothermal systems on early Earth could have provided a substantial source of biomolecules required for the origin of life. Astrobiology 9, 141-146. ?? 2009 Mary Ann Liebert, Inc. 2009.

  16. Effect of Hydrothermal Treatment on Sinterability of Hydroxyapatite

    SciTech Connect

    Kawagoe, D.; Fujimori, H.; Goto, S.; Yamasaki, N.; Ioku, K.

    2006-05-15

    Calcium hydroxyapatite, Ca10(PO4)6(OH)2:HA, is the inorganic principle component of natural bones and teeth. It has been already suggested that the amount of OH ion in the crystal structure of HA is closely related to the biocompatibility. The amount of OH ion in current HA, however, has not been controlled. In order to prepare more functional HA ceramics, the amount of OH ion must be controlled. In this study, HA ceramics with different OH amount were prepared from fine HA crystals by spark plasma sintering (SPS). Fine powder of HA was treated hydrothermally at 200 deg. C for 24 h with pH 10 NH3 aqueous solution. The samples were pressed uniaxialy under 60 MPa, and then they were SPS at 800 deg. C, 900 deg. C and 1000 deg. C for 10 min with the heating rate of 25 deg. C{center_dot}min-1. No phases other than HA were revealed by XRD for the starting samples after hydrothermal treatment and samples after sintering by SPS at 800 deg. C, 900 deg. C and 1000 deg. C for 10 min. The quantity of OH ion in HA ceramics sintered by SPS was decreased with increasing temperature of sintering. Transparent HA ceramics were prepared by SPS at 900 deg. C and 1000 deg. C.

  17. Structural reorganisation of cellulose fibrils in hydrothermally deconstructed lignocellulosic biomass and relationships with enzyme digestibility

    PubMed Central

    2013-01-01

    Background The investigation of structural organisation in lignocellulose materials is important to understand changes in cellulase accessibility and reactivity resulting from hydrothermal deconstruction, to allow development of strategies to maximise bioethanol process efficiencies. To achieve progress, wheat straw lignocellulose and comparative model wood cellulose were characterised following increasing severity of hydrothermal treatment. Powder and fibre wide-angle X-ray diffraction techniques were employed (WAXD), complemented by enzyme kinetic measurements up to high conversion. Results Evidence from WAXD indicated that cellulose fibrils are not perfectly crystalline. A reduction in fibril crystallinity occurred due to hydrothermal treatment, although dimensional and orientational data showed that fibril coherency and alignment were largely retained. The hypothetical inter-fibril spacing created by hydrothermal deconstruction of straw was calculated to be insufficient for complete access by cellulases, although total digestion of cellulose in both treated straw and model pulp was observed. Both treated straw and model pulps were subjected to wet mechanical attrition, which caused separation of smaller fibril aggregates and fragments, significantly increasing enzyme hydrolysis rate. No evidence from WAXD measurements was found for preferential hydrolysis of non-crystalline cellulose at intermediate extent of digestion, for both wood pulp and hydrothermally treated straw. Conclusions The increased efficiency of enzyme digestion of cellulose in the lignocellulosic cell wall following hydrothermal treatment is a consequence of the improved fibril accessibility due to the loss of hemicellulose and disruption of lignin. However, incomplete accessibility of cellulase at the internal surfaces of fibrillar aggregates implies that etching type mechanisms will be important in achieving complete hydrolysis. The reduction in crystalline perfection following hydrothermal

  18. Numerical models of caldera deformation: Effects of multiphase and multicomponent hydrothermal fluid flow

    USGS Publications Warehouse

    Hutnak, M.; Hurwitz, S.; Ingebritsen, S.E.; Hsieh, P.A.

    2009-01-01

    Ground surface displacement (GSD) in large calderas is often interpreted as resulting from magma intrusion at depth. Recent advances in geodetic measurements of GSD, notably interferometric synthetic aperture radar, reveal complex and multifaceted deformation patterns that often require complex source models to explain the observed GSD. Although hydrothermal fluids have been discussed as a possible deformation agent, very few quantitative studies addressing the effects of multiphase flow on crustal mechanics have been attempted. Recent increases in the power and availability of computing resources allow robust quantitative assessment of the complex time-variant thermal interplay between aqueous fluid flow and crustal deformation. We carry out numerical simulations of multiphase (liquid-gas), multicomponent (H 2O-CO2) hydrothermal fluid flow and poroelastic deformation using a range of realistic physical parameters and processes. Hydrothermal fluid injection, circulation, and gas formation can generate complex, temporally and spatially varying patterns of GSD, with deformation rates, magnitudes, and geometries (including subsidence) similar to those observed in several large calderas. The potential for both rapid and gradual deformation resulting from magma-derived fluids suggests that hydrothermal fluid circulation may help explain deformation episodes at calderas that have not culminated in magmatic eruption.

  19. Silica nanoparticles as indicator of hydrothermal activities at Enceladus ocean floor

    NASA Astrophysics Data System (ADS)

    Postberg, F.; Hsu, S.; Sekine, Y.; Kempf, S.; Juhasz, A.; Horanyi, M.; Moragas-Klostermeyer, G.; Srama, R.

    2013-12-01

    hydrothermal liquid, probably as it travels upwards towards the surface (e.g., Matson et al., 2012). The temperatures of the near surface waters which fuel the plume are close to 0°C (Schmidt et al. 2008). Formation and stablility of a nano-colloidal silica phase requires alkaline pH (8 - 10) and only tolerates a mild salinity, not higher than a few percent, which agrees with previous compositional measurements of ice grains in Enceladus plume (Postberg et al. 2009, 2011).

  20. Hydrothermal mineralization at seafloor spreading centers

    NASA Astrophysics Data System (ADS)

    Rona, Peter A.

    1984-01-01

    The recent recognition that metallic mineral deposits are concentrated by hydrothermal processes at seafloor spreading centers constitutes a scientific breakthrough that opens active sites at seafloor spreading centers as natural laboratories to investigate ore-forming processes of such economically useful deposits as massive sulfides in volcanogenic rocks on land, and that enhances the metallic mineral potential of oceanic crust covering two-thirds of the Earth both beneath ocean basins and exposed on land in ophiolite belts. This paper reviews our knowledge of processes of hydrothermal mineralization and the occurrence and distribution of hydrothermal mineral deposits at the global oceanic ridge-rift system. Sub-seafloor hydrothermal convection involving circulation of seawater through fractured rocks of oceanic crust driven by heat supplied by generation of new lithosphere is nearly ubiquitous at seafloor spreading centers. However, ore-forming hydrothermal systems are extremely localized where conditions of anomalously high thermal gradients and permeability increase hydrothermal activity from the ubiquitous low-intensity background level (⩽ 200°C) to high-intensity characterized by high temperatures ( > 200-c.400°C), and a rate and volume of flow sufficient to sustain chemical reactions that produce acid, reducing, metal-rich primary hydrothermal solutions. A series of mineral phases with sulfides and oxides as high- and low-temperature end members, respectively, are precipitated along the upwelling limb and in the discharge zone of single-phase systems as a function of increasing admixture of normal seawater. The occurrence of hydrothermal mineral deposits is considered in terms of spatial and temporal frames of reference. Spatial frames of reference comprise structural features along-axis (linear sections that are the loci of seafloor spreading alternating with transform faults) and perpendicular to axis (axial zone of volcanic extrusion and marginal

  1. Studies on supercritical hydrothermal syntheses of uranium and lanthanide oxide particles and their reaction mechanisms

    NASA Astrophysics Data System (ADS)

    Hwang, DongKi; Tsukahara, Takehiko; Tanaka, Kosuke; Osaka, Masahiko; Ikeda, Yasuhisa

    2015-11-01

    In order to develop preparation method of raw metal oxide particles for low decontaminated MOX fuels by supercritical hydrothermal (SH) treatments, we have investigated behavior of aqueous solutions dissolving U(VI), Ln(III) (Ln: lanthanide = Ce, Pr, Nd, Sm, Tb), Cs(I), and Sr(II) nitrate or chloride compounds under SH conditions (temperature = 400-500 °C, pressure = 30-40 MPa). As a result, it was found that Ln(NO3)3 (Ln = Ce, Pr, Tb) compounds produce LnO2, that Ln(NO3)3 (Ln = Nd, Sm) compounds are hardly converted to their oxides, and that LnCl3 (Ln = Ce, Pr, Nd, Sm, Tb), CsNO3, and Sr(NO3)2 do not form their oxide compounds. Furthermore, HNO2 species were detected in the liquid phase obtained after treating HNO3 aqueous solutions containing Ln(NO3)3 (Ln = Ce, Pr, Tb) under SH conditions, and also NO2 and NO compounds were found to be produced by decomposition of HNO3. From these results, it was proposed that the Ln oxide (LnO2) particles are directly formed with oxidation of Ln(III) to Ln(IV) by HNO3 and HNO2 species in the SH systems. Moreover, the uranyl ions were found to form U3O8 and UO3 depending on the concentration of HNO3. From these results, it is expected that the raw metal oxide particles for low decontaminated MOX fuels are efficiently prepared by the SH method.

  2. Calibrated Hydrothermal Parameters, Barrow, Alaska, 2013

    DOE Data Explorer

    Atchley, Adam; Painter, Scott; Harp, Dylan; Coon, Ethan; Wilson, Cathy; Liljedahl, Anna; Romanovsky, Vladimir

    2015-01-29

    A model-observation-experiment process (ModEx) is used to generate three 1D models of characteristic micro-topographical land-formations, which are capable of simulating present active thaw layer (ALT) from current climate conditions. Each column was used in a coupled calibration to identify moss, peat and mineral soil hydrothermal properties to be used in up-scaled simulations. Observational soil temperature data from a tundra site located near Barrow, AK (Area C) is used to calibrate thermal properties of moss, peat, and sandy loam soil to be used in the multiphysics Advanced Terrestrial Simulator (ATS) models. Simulation results are a list of calibrated hydrothermal parameters for moss, peat, and mineral soil hydrothermal parameters.

  3. Thermodynamics of Strecker synthesis in hydrothermal systems

    NASA Technical Reports Server (NTRS)

    Schulte, Mitchell; Shock, Everett

    1995-01-01

    Submarine hydrothermal systems on the early Earth may have been the sites from which life emerged. The potential for Strecker synthesis to produce biomolecules (amino and hydroxy acids) from starting compounds (ketones, aldehydes, HCN and ammonia) in such environments is evaluated quantitatively using thermodynamic data and parameters for the revised Helgeson-Kirkham-Flowers (HKF) equation of state. Although there is an overwhelming thermodynamic drive to form biomolecules by the Strecker synthesis at hydrothermal conditions, the availability and concentration of starting compounds limit the efficiency and productivity of Strecker reactions. Mechanisms for concentrating reactant compounds could help overcome this problem, but other mechanisms for production of biomolecules may have been required to produce the required compounds on the early Earth. Geochemical constraints imposed by hydrothermal systems provide important clues for determining the potential of these and other systems as sites for the emergence of life.

  4. Hydrothermal Ni Prospectivity Analysis of Tasmania, Australia

    NASA Astrophysics Data System (ADS)

    Gonzalez-Alvalez, I.; Porwal, A.; McCuaig, T. C.

    2009-04-01

    Tasmania contains the largest hydrothermal Ni deposit in Australia: Avebury (118,000 Ni metal tonnes). This Devonian deposit was discovered in 1998 in the Dundas geological region, and represents an outstanding example of hydrothermal Nickel sulphide mineralization type. Avebury Ni deposit is a system of hydrothermal Ni ore bodies. It is hosted by an intensely altered and serpentinized Cambrian ultramafic suite in close proximity to major structural features. The mineralization is considered to be the result of hydrothermal scavenging and remobilization of the original nickel content of the mafic/ultramafic rocks in the area, and subsequent re-deposition in favourable structural traps. The mineralization is spatially and temporally related to a large granitic intrusion, the Heemskirk Granite, which is considered to be the source of the hydrothermal fluids as well as the necessary thermal gradients for the circulation of the fluids. Tasmania is largely covered by the Jurassic Ferrar Continental Flood basalt Province in the East and presents early Cambrian ultramafic-mafic complexes in the West. The Ferrar large igneous province (LIP) extends over to Antarctica and is related to the Karoo Province in southern Africa that comprises tholeiitic lava flows, sills, and dyke swarms. The Ferrar and Karoo provinces were associated with the same thermal anomaly that was involved in the break up of Gondwana. The presence of mafic/ultramafic rocks in favourable lithological packages and/or structural traps along the margins of the province, as well as several prospective reduced or reactive sedimentary packages within and around the Ferrar indicate that this LIP could represent a novel promising ground for Ni hydrothermal exploration. Based on this prospective geological background, a prospectivity analysis for hydrothermal Ni deposits was carried out on regional scale for the entire state of Tasmania. A conceptual model of hydrothermal nickel mineral system was used to

  5. Hydrothermal Ni Prospectivity Analysis of Tasmania, Australia

    NASA Astrophysics Data System (ADS)

    Gonzalez-Alvarez, I.; Porwal, A.; McCuaig, T. C.; Maier, W.

    2009-04-01

    Tasmania contains the largest hydrothermal Ni deposit in Australia: Avebury (118,000 Ni metal tonnes). This Devonian deposit was discovered in 1998 in the Dundas geological region, and consists of a system of hydrothermal Ni ore bodies. They are hosted by an intensely altered and serpentinized Cambrian ultramafic suite in close proximity to major structural features. The mineralization is considered to be the result of hydrothermal scavenging and remobilization of the original nickel content of mafic/ultramafic rocks in the area, and subsequent re-deposition in favourable structural traps. This is based on the low sulphur, low Cu and Platinum element content of the mineralization. The mineralization is spatially (at the edge) and temporally related to a large granitic intrusion, the Heemskirk Granite, which is considered to be the source of the hydrothermal fluids as well as the necessary thermal gradients for the circulation of the fluids. Tasmania is largely covered by the Jurassic Ferrar continental flood basalt province in the East and constrains a number of early Cambrian ultramafic-mafic complexes in the West. The Ferrar large igneous province (LIP) extends over to Antarctica and is temporally and genetically related to the Karoo igneous province in southern Africa that comprises tholeiitic lava flows, sills, and dyke swarms. The Ferrar and Karoo igneous provinces were associated with the same thermal anomaly that was responsible for the break up of eastern Gondwana at ca 180 Ma. Despite of timeframe differences between the Avebury Ni deposits and the Ferrar LIP emplacement, similar geological settings to the Avebury could be duplicated along the Ferrar LIP. The presence of mafic/ultramafic rocks in favourable lithological packages and/or structural traps along the margins of the province indicate that this LIP could represent a possible exploration target for Ni hydrothermal deposits. Based on this background, a prospectivity analysis for hydrothermal Ni

  6. Hydrothermal processing of radioactive combustible waste

    SciTech Connect

    Worl, L.A.; Buelow, S.J.; Harradine, D.; Le, L.; Padilla, D.D.; Roberts, J.H.

    1998-09-01

    Hydrothermal processing has been demonstrated for the treatment of radioactive combustible materials for the US Department of Energy. A hydrothermal processing system was designed, built and tested for operation in a plutonium glovebox. Presented here are results from the study of the hydrothermal oxidation of plutonium and americium contaminated organic wastes. Experiments show the destruction of the organic component to CO{sub 2} and H{sub 2}O, with 30 wt.% H{sub 2}O{sub 2} as an oxidant, at 540 C and 46.2 MPa. The majority of the actinide component forms insoluble products that are easily separated by filtration. A titanium liner in the reactor and heat exchanger provide corrosion resistance for the oxidation of chlorinated organics. The treatment of solid material is accomplished by particle size reduction and the addition of a viscosity enhancing agent to generate a homogeneous pumpable mixture.

  7. Impact of food to microorganism (F/M) ratio and colloidal chemical oxygen demand on nitrification performance of a full-scale membrane bioreactor treating thin film transistor liquid crystal display wastewater.

    PubMed

    Wu, Yi-Ju; Whang, Liang-Ming; Chang, Ming-Yu; Fukushima, Toshikazu; Lee, Ya-Chin; Cheng, Sheng-Shung; Hsu, Shu-Fu; Chang, Cheng-Huey; Shen, Wason; Yang, Charn-Yi; Fu, Ryan; Tsai, Tsair-Yuan

    2013-08-01

    This study investigated impact of food to microorganism (F/M) ratio and colloidal chemical oxygen demand (COD) on nitrification performance in one full-scale membrane bioreactor (MBR) treating monoethanolamine (MEA)/dimethyl sulfoxide (DMSO)-containing thin film transistor liquid crystal display (TFT-LCD) wastewater. Poor nitrification was observed under high organic loading and high colloidal COD conditions, suggesting that high F/M ratio and colloidal COD situations should be avoided to minimize their negative impacts on nitrification. According to the nonmetric multidimensional scaling (NMS) statistical analyses on terminal restriction fragment length polymorphism (T-RFLP) results of ammonia monooxygenase (amoA) gene, the occurrence of Nitrosomonas oligotropha-like ammonia oxidizing bacteria (AOB) was positively related to successful nitrification in the MBR systems, while Nitrosomonas europaea-like AOB was positively linked to nitrification rate, which can be attributed to the high influent total nitrogen condition. Furthermore, Nitrobacter- and Nitrospira-like nitrite oxidizing bacteria (NOB) were both abundant in the MBR systems, but the continuously low nitrite environment is likely to promote the growth of Nitrospira-like NOB.

  8. Geothermal reservoirs in hydrothermal convection systems

    SciTech Connect

    Sorey, M.L.

    1982-01-01

    Geothermal reservoirs commonly exist in hydrothermal convection systems involving fluid circulation downward in areas of recharge and upwards in areas of discharge. Because such reservoirs are not isolated from their surroundings, the nature of thermal and hydrologic connections with the rest of the system may have significant effects on the natural state of the reservoir and on its response to development. Conditions observed at numerous developed and undeveloped geothermal fields are discussed with respect to a basic model of the discharge portion of an active hydrothermal convection system. Effects of reservoir development on surficial discharge of thermal fluid are also delineated.

  9. Enhanced hydrothermal stability of Cu-ZSM-5 catalyst via surface modification in the selective catalytic reduction of NO with NH3

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Shi, Juan; Liu, Jian; Wang, Daxi; Zhao, Zhen; Cheng, Kai; Li, Jianmei

    2016-07-01

    The surface of Cu-ZSM-5 catalyst was modified by chemical liquid deposition (CLD) of tetraethoxysilane (TEOS) for enhancing its hydrothermal stability in the selective catalytic reduction of NO with NH3. After hydrothermal aging at 750 °C for 13 h, the catalytic performance of Cu-ZSM-5-Aged catalyst was significantly reduced for NO reduction in the entire temperature range, while that of Cu-ZSM-5-CLD-Aged catalyst was affected very little. The characterization results indicated that an inert silica layer was deposited on the surface of Cu-ZSM-5 and formed a protective layer, which prevents the detachment of Cu2+ from ZSM-5 ion-exchange positions and the dealumination of zeolite during the hydrothermal aging process. Based on the data it is hypothesized to be the primary reason for the high hydrothermal stability of Cu-ZSM-5-CLD catalyst.

  10. Biogeochemistry of hydrothermally and adjacent non-altered soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a field/lab project, students in the Soil Biogeochemistry class of the University of Nevada, Reno described and characterized seven pedons, developed in hydrothermally and adjacent non-hydrothermally altered andesitic parent material near Reno, NV. Hydrothermally altered soils had considerably lo...

  11. Treating Meningitis

    MedlinePlus

    ... ways to treat bacterial meningitis. 1 They compared steroids (dexamethasone) with pla- cebo. The doctors gave medication ( ... compared anti- biotics by themselves with antibiotics plus steroids. Dr. Fritz and colleagues compared the mortality (deaths) ...

  12. Understanding effect of wall structure on the hydrothermal stability of mesostructured silica SBA-15.

    PubMed

    Zhang, Fuqiang; Yan, Yan; Yang, Haifeng; Meng, Yan; Yu, Chengzhong; Tu, Bo; Zhao, Dongyuan

    2005-05-12

    , resulting in smaller pore diameter and low surface area. A carbon-propping thermal treating method was employed to enhance the polymerization of Si-O-Si bonds and minimize the serious shrinkage of mesopores at the same time. It was demonstrated to be an effective method that can greatly improve the hydrothermal stability of SBA-15 materials in 800 degrees C steam for 12 h. Furthermore, the SBA-15 materials obtained by using the carbon-propping method possess larger pores and higher surface area after the steam treatment at 800 degrees C compared to the materials from the direct thermal treatment method after the steam treatment.

  13. The chemistry of hydrothermal magnetite: a review

    USGS Publications Warehouse

    Nadoll, Patrick; Angerer, Thomas; Mauk, Jeffrey L.; French, David; Walshe, John

    2014-01-01

    Magnetite (Fe3O4) is a well-recognized petrogenetic indicator and is a common accessory mineral in many ore deposits and their host rocks. Recent years have seen an increased interest in the use of hydrothermal magnetite for provenance studies and as a pathfinder for mineral exploration. A number of studies have investigated how specific formation conditions are reflected in the composition of the respective magnetite. Two fundamental questions underlie these efforts — (i) How can the composition of igneous and, more importantly, hydrothermal magnetite be used to discriminate mineralized areas from barren host rocks, and (ii) how can this assist exploration geologists to target ore deposits at greater and greater distances from the main mineralization? Similar to igneous magnetite, the most important factors that govern compositional variations in hydrothermal magnetite are (A) temperature, (B) fluid composition — element availability, (C) oxygen and sulfur fugacity, (D) silicate and sulfide activity, (E) host rock buffering, (F) re-equilibration processes, and (G) intrinsic crystallographic controls such as ionic radius and charge balance. We discuss how specific formation conditions are reflected in the composition of magnetite and review studies that investigate the chemistry of hydrothermal and igneous magnetite from various mineral deposits and their host rocks. Furthermore, we discuss the redox-related alteration of magnetite (martitization and mushketovitization) and mineral inclusions in magnetite and their effect on chemical analyses. Our database includes published and previously unpublished magnetite minor and trace element data for magnetite from (1) banded iron formations (BIF) and related high-grade iron ore deposits in Western Australia, India, and Brazil, (2) Ag–Pb–Zn veins of the Coeur d'Alene district, United States, (3) porphyry Cu–(Au)–(Mo) deposits and associated (4) calcic and magnesian skarn deposits in the southwestern United

  14. Hydrothermal alkali metal recovery process

    DOEpatents

    Wolfs, Denise Y.; Clavenna, Le Roy R.; Eakman, James M.; Kalina, Theodore

    1980-01-01

    In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered from the particles by treating them with a calcium or magnesium-containing compound in the presence of water at a temperature between about 250.degree. F. and about 700.degree. F. and in the presence of an added base to establish a pH during the treatment step that is higher than would otherwise be possible without the addition of the base. During the treating process the relatively high pH facilitates the conversion of water-insoluble alkali metal compounds in the alkali metal residues into water-soluble alkali metal constituents. The resultant aqueous solution containing water-soluble alkali metal constituents is then separated from the residue solids, which consist of the treated particles and any insoluble materials formed during the treatment step, and recycled to the gasification process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst. Preferably, the base that is added during the treatment step is an alkali metal hydroxide obtained by water washing the residue solids produced during the treatment step.

  15. High-pressure homogenization associated hydrothermal process of palygorskite for enhanced adsorption of Methylene blue

    NASA Astrophysics Data System (ADS)

    Zhang, Zhifang; Wang, Wenbo; Wang, Aiqin

    2015-02-01

    Palygorskite (PAL) was modified by a high-pressure homogenization assisted hydrothermal process. The effects of modification on the morphology, structure and physicochemical properties of PAL were systematically investigated by Field-emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FTIR), Brunauer-Emmett-Teller (BET) analysis, X-ray diffraction (XRD) and Zeta potential analysis techniques, and the adsorption properties were systematically evaluated using Methylene blue (MB) as the model dye. The results revealed that the crystal bundles were disaggregated and the PAL nanorods became more even after treated via associated high-pressure homogenization and hydrothermal process, and the crystal bundles were dispersed as nanorods. The intrinsic crystal structure of PAL was remained after hydrothermal treatment, and the pore size calculated by the BET method was increased. The adsorption properties of PAL for MB were evidently improved (from 119 mg/g to 171 mg/g) after modification, and the dispersion of PAL before hydrothermal reaction is favorable to the adsorption. The desorption evaluation confirms that the modified PAL has stronger affinity with MB, which is benefit to fabricate a stable organic-inorganic hybrid pigment.

  16. Polymer Assisted Core-shell Ag-C nanoparticles Synthesis via Green hydrothermal Technique

    NASA Astrophysics Data System (ADS)

    Williams, James; Mishra, Sanjay

    2009-03-01

    Core-Shell Ag-C nanoparticles were synthesized in the presence of glucose through a one-pot green hydrothermal wet chemical process. An aqueous solution of glucose and Ag nitrate was hydrothermally treated to produce porous carbonaceous shell over silver core nanoparticles. The growth of carbon shells was regulated by either of the polymers (poly) vinyl pyrrolidone (PVP) or poly vinyl alcohol (PVA). The two polymers were compared to take a measure of different tunable sizes of cores, and shells. The effects of hydrothermal temperature, time, and concentration of reagents on the final formation of nanostructures were studied using UV-vis extinction spectra, transmission electron microscope, and Raman spectroscopy. The polymer molecules were found to be incorporated into carbonaceous shell. The resulting opacity of the shell was found to be hydrothermal time and temperature dependent. The shell structure was found to be more uniform with PVP than PVA. Furthermore, the polymer concentration was found to influence size and shape of the core-silver particles as well. The core-shelled nanoparticles have surfaces with organic groups capable of assembling with different reagents that could be useful in drug-delivery, optical nanodevices or biochemistry.

  17. Recrystallization of starches by hydrothermal treatment: digestibility, structural, and physicochemical properties.

    PubMed

    Trinh, Khanh Son

    2015-12-01

    Gelatinized starches were recrystallized under hydrothermal treatment and their properties were characterized by X-ray diffractometry, solid-state (13)C cross-polarization and magic-angle spinning nuclear magnetic resonance, differential scanning calorimetry, gel-permeation chromatography, high-performance anion-exchange chromatography using pulsed amperomeric detection, high-performance size-exclusion chromatography with attached multiangle laser light scattering and refractive index detectors, and digestibility analysis. Amylopectin molecules of hylon (V, VII) and water yam starch contained long side-chains with high proportion of fb1 and fb2. Under hydrothermal treatment, the double helix proportion and relative crystallinity significantly increased and reached maxima of water yam (48.7 and 28.2 %, respectively). Except water yam starch, X-ray diffraction pattern of all starches exhibited the evidence of type 2 amylose-lipid complex. Besides, under DSC measurement, potato and hylon starches showed the endotherm of amylose-amylose interaction. The hydrothermal treatment caused the recrystallization resulting in the decrease of RDS, especially in case of hylon and water yam starch. HTT water yam contained highest SDS (48.3 %) and HTT hylon VII contained highest RS (44.5 %). The relationship between structure and digestibility was observed, in which, high amylose content and specific structures of amylopectin molecule were necessary for the production of RS and/or SDS of hydrothermally treated starches.

  18. A large hydrothermal reservoir beneath Taal Volcano (Philippines) revealed by magnetotelluric observations and its implications to the volcanic activity.

    PubMed

    Alanis, Paul K B; Yamaya, Yusuke; Takeuchi, Akihiro; Sasai, Yoichi; Okada, Yoshihiro; Nagao, Toshiyasu

    2013-01-01

    Taal Volcano is one of the most active volcanoes in the Philippines. The magnetotelluric 3D forward analyses indicate the existence of a large high resistivity anomaly (∼100 Ω·m) with a volume of at least 3 km×3 km×3 km, which is capped by a conductive layer (∼10 Ω·m), beneath the Main Crater. This high resistivity anomaly is hypothesized to be a large hydrothermal reservoir, consisting of the aggregate of interconnected cracks in rigid and dense host rocks, which are filled with hydrothermal fluids coming from a magma batch below the reservoir. The hydrothermal fluids are considered partly in gas phase and liquid phase. The presence of such a large hydrothermal reservoir and the stagnant magma below may have influences on the volcano's activity. Two possibilities are presented. First, the 30 January 1911 explosion event was a magmatic hydrothermal eruption rather than a base-surge associated with a phreato-magmatic eruption. Second, the earlier proposed four eruption series may be better interpreted by two cycles, each consisting of series of summit and flank eruptions. PMID:24126286

  19. A large hydrothermal reservoir beneath Taal Volcano (Philippines) revealed by magnetotelluric observations and its implications to the volcanic activity

    PubMed Central

    ALANIS, Paul K. B.; YAMAYA, Yusuke; TAKEUCHI, Akihiro; SASAI, Yoichi; OKADA, Yoshihiro; NAGAO, Toshiyasu

    2013-01-01

    Taal Volcano is one of the most active volcanoes in the Philippines. The magnetotelluric 3D forward analyses indicate the existence of a large high resistivity anomaly (∼100 Ω·m) with a volume of at least 3 km × 3 km × 3 km, which is capped by a conductive layer (∼10 Ω·m), beneath the Main Crater. This high resistivity anomaly is hypothesized to be a large hydrothermal reservoir, consisting of the aggregate of interconnected cracks in rigid and dense host rocks, which are filled with hydrothermal fluids coming from a magma batch below the reservoir. The hydrothermal fluids are considered partly in gas phase and liquid phase. The presence of such a large hydrothermal reservoir and the stagnant magma below may have influences on the volcano’s activity. Two possibilities are presented. First, the 30 January 1911 explosion event was a magmatic hydrothermal eruption rather than a base-surge associated with a phreato-magmatic eruption. Second, the earlier proposed four eruption series may be better interpreted by two cycles, each consisting of series of summit and flank eruptions. PMID:24126286

  20. A large hydrothermal reservoir beneath Taal Volcano (Philippines) revealed by magnetotelluric observations and its implications to the volcanic activity.

    PubMed

    Alanis, Paul K B; Yamaya, Yusuke; Takeuchi, Akihiro; Sasai, Yoichi; Okada, Yoshihiro; Nagao, Toshiyasu

    2013-01-01

    Taal Volcano is one of the most active volcanoes in the Philippines. The magnetotelluric 3D forward analyses indicate the existence of a large high resistivity anomaly (∼100 Ω·m) with a volume of at least 3 km×3 km×3 km, which is capped by a conductive layer (∼10 Ω·m), beneath the Main Crater. This high resistivity anomaly is hypothesized to be a large hydrothermal reservoir, consisting of the aggregate of interconnected cracks in rigid and dense host rocks, which are filled with hydrothermal fluids coming from a magma batch below the reservoir. The hydrothermal fluids are considered partly in gas phase and liquid phase. The presence of such a large hydrothermal reservoir and the stagnant magma below may have influences on the volcano's activity. Two possibilities are presented. First, the 30 January 1911 explosion event was a magmatic hydrothermal eruption rather than a base-surge associated with a phreato-magmatic eruption. Second, the earlier proposed four eruption series may be better interpreted by two cycles, each consisting of series of summit and flank eruptions.

  1. Agricultural residue valorization using a hydrothermal process for second generation bioethanol and oligosaccharides production.

    PubMed

    Vargas, Fátima; Domínguez, Elena; Vila, Carlos; Rodríguez, Alejandro; Garrote, Gil

    2015-09-01

    In the present work, the hydrothermal valorization of an abundant agricultural residue has been studied in order to look for high added value applications by means of hydrothermal pretreatment followed by fed-batch simultaneous saccharification and fermentation, to obtain oligomers and sugars from autohydrolysis liquors and bioethanol from the solid phase. Non-isothermal autohydrolysis was applied to barley straw, leading to a solid phase with about a 90% of glucan and lignin and a liquid phase with up to 168 g kg(-1) raw material valuable hemicellulose-derived compounds. The solid phase showed a high enzymatic susceptibility (up to 95%). It was employed in the optimization study of the fed-batch simultaneous saccharification and fermentation, carried out at high solids loading, led up to 52 g ethanol/L (6.5% v/v).

  2. Using toughreact to model reactive fluid flow and geochemical transport in hydrothermal systems

    SciTech Connect

    Xu, Tianfu; Sonnenthal, Eric; Spycher, Nicolas; Pruess, Karsten

    2003-07-31

    The interaction between hydrothermal fluids and the rocks through which they migrate alters the earlier formed primary minerals and leads to the formation of secondary minerals, resulting in changes in the physical and chemical properties of the system. We have developed a comprehensive numerical simulator, TOUGHREACT, which considers nonisothermal multi-component chemical transport in both liquid and gas phases. A variety of subsurface thermo-physical-chemical processes is considered under a wide range of conditions of pressure, temperature, water saturation, and ionic strength. The code can be applied to problems in fundamental analysis of the hydrothermal systems and in the exploration of geothermal reservoirs including chemical evolution, mineral alteration, mineral scaling, changes of porosity and permeability, and mineral recovery from geothermal fluids.

  3. Hydrothermal systems and the emergence of life

    NASA Technical Reports Server (NTRS)

    Shock, E. L.

    1994-01-01

    The author reviews current thought about life originating in hyperthermophilic microorganisms. Hyperthermophiles obtain food from chemosynthesis of sulfur and have an RNA nucleotide sequence different from bacteria and eucarya. It is postulated that a hyperthermophile may be the common ancestor of all life. Current research efforts focus on the synthesis of organic compounds in hydrothermal systems.

  4. Hydrothermal exploration with the Autonomous Benthic Explorer

    NASA Astrophysics Data System (ADS)

    German, Christopher R.; Yoerger, Dana R.; Jakuba, Michael; Shank, Timothy M.; Langmuir, Charles H.; Nakamura, Ko-ichi

    We describe a three-phase use of the Woods Hole Oceanographic Institution's Autonomous Benthic Explorer ( ABE), to locate, map and photograph previously undiscovered fields of high temperature submarine hydrothermal vents. Our approach represents both a complement to and a significant advance beyond the prior state of the art. Previously, hydrothermal exploration relied upon deep-tow instruments equipped with sensors that could locate sites of active "black smoker" venting to within a few kilometers. Follow-on CTD tow-yos could then resolve the sites of seafloor venting to length scales of less than a kilometer but rarely to better than a few hundreds of meters. In our new approach ABE: (i) uses sensors to locate the center of a dispersing non-buoyant hydrothermal plume 100-400 m above the seabed; (ii) makes high-resolution maps of the seafloor beneath the plume center whilst simultaneously detecting interception of any rising, buoyant hydrothermal plumes; and (iii) dives to the seafloor to take photographs in and around any new vent site to characterize its geologic setting and reveal the nature of any chemosynthetic ecosystems it may host. By conducting all of the above under long-baseline navigation, precise sites of venting can be determined to within 5 m. Our approach can be used both to address important scientific issues in their own right and to ensure much more efficient use of other deep-submergence assets such as human occupied vehicles (HOVs) and remotely operated vehicles (ROVs) during follow-on studies.

  5. The Biogeochemistry of Sulfur in Hydrothermal Systems

    NASA Technical Reports Server (NTRS)

    Schulte, Mitchell; Rogers, K. L.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    The incorporation of sulfur into many biomolecules likely dates back to the development of the earliest metabolic strategies. Sulfur is common in enzymes and co-enzymes and is an indispensable structural component in many peptides and proteins. Early metabolism may have been heavily influenced by the abundance of sulfide minerals in hydrothermal systems. The incorporation of sulfur into many biomolecules likely dates back to the development of the earliest metabolic strategies. Sulfur is common in enzymes and co-enzymes and is an indispensable structural component in many peptides and proteins. Early metabolism may have been heavily influenced by the abundance of sulfide minerals in hydrothermal systems. Understanding how sulfur became prevalent in biochemical processes and many biomolecules requires knowledge of the reaction properties of sulfur-bearing compounds. We have previously estimated thermodynamic data for thiols, the simplest organic sulfur compounds, at elevated temperatures and pressures. If life began in hydrothermal environments, it is especially important to understand reactions at elevated temperatures among sulfur-bearing compounds and other organic molecules essential for the origin and persistence of life. Here we examine reactions that may have formed amino acids with thiols as reaction intermediates in hypothetical early Earth hydrothermal environments. (There are two amino acids, cysteine and methionine, that contain sulfur.) Our calculations suggest that significant amounts of some amino acids were produced in early Earth hydrothermal fluids, given reasonable concentrations H2, NH3, H2S and CO. For example, preliminary results indicate that glycine activities as high as 1 mmol can be reached in these systems at 100 C. Alanine formation from propanethiol is also a favorable reaction. On the other hand, the calculated equilibrium log activities of cysteine and serine from propanethiol are -21 and -19, respectively, at 100 C. These results

  6. Anhydrite precipitation in seafloor hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Theissen-Krah, Sonja; Rüpke, Lars H.

    2016-04-01

    The composition and metal concentration of hydrothermal fluids venting at the seafloor is strongly temperature-dependent and fluids above 300°C are required to transport metals to the seafloor (Hannington et al. 2010). Ore-forming hydrothermal systems and high temperature vents in general are often associated with faults and fracture zones, i.e. zones of enhanced permeabilities that act as channels for the uprising hydrothermal fluid (Heinrich & Candela, 2014). Previous numerical models (Jupp and Schultz, 2000; Andersen et al. 2015) however have shown that high permeabilities tend to decrease fluid flow temperatures due to mixing with cold seawater and the resulting high fluid fluxes that lead to short residence times of the fluid near the heat source. A possible mechanism to reduce the permeability and thereby to focus high temperature fluid flow are mineral precipitation reactions that clog the pore space. Anhydrite for example precipitates from seawater if it is heated to temperatures above ~150°C or due to mixing of seawater with hydrothermal fluids that usually have high Calcium concentrations. We have implemented anhydrite reactions (precipitation and dissolution) in our finite element numerical models of hydrothermal circulation. The initial results show that the precipitation of anhydrite efficiently alters the permeability field, which affects the hydrothermal flow field as well as the resulting vent temperatures. C. Andersen et al. (2015), Fault geometry and permeability contrast control vent temperatures at the Logatchev 1 hydrothermal field, Mid-Atlantic Ridge, Geology, 43(1), 51-54. M. D. Hannington et al. (2010), Modern Sea-Floor Massive Sulfides and Base Metal Resources: Toward an Estimate of Global Sea-Floor Massive Sulfide Potential, in The Challenge of Finding New Mineral Resources: Global Metallogeny, Innovative Exploration, and New Discoveries, edited by R. J. Goldfarb, E. E. Marsh and T. Monecke, pp. 317-338, Society of Economic Geologists

  7. Microbial sulfate reduction within the Iheya North subseafloor hydrothermal system constrained by quadruple sulfur isotopes

    NASA Astrophysics Data System (ADS)

    Aoyama, S.; Nishizawa, M.; Takai, K.; Ueno, Y.

    2012-12-01

    Subseafloor hydrothermal system may host active and abundant microbial community. Sulfate reduction may be one of the dominant microbial metabolisms among the subseafloor ecosystem. In order to demonstrate and quantify the potential sulfate reducing activity, we analyzed sulfur isotopes (32S/33S/34S/36S) of pore water sulfate extracted from core samples at the Iheya North hydrothermal system in the Okinawa drilled by CHIKYU, 2009 (IODP Leg 331). After drilling, core samples were divided into several sections. Then, pore water was extracted on board, and stored with cadmium chloride for fixing hydrogen sulfide. In our laboratory, the samples were first divided into sulfide precipitate and supernatant liquid by centrifugation. Then, dissolved sulfate was precipitated as BaSO4 by addition of barium chloride into the supernatant liquid. After weighing, the barium sulfate was converted into silver sulfide and subsequently sulfur hexafluoride, which was purified by GC and then introduced into mass spectrometer (MAT253) through newly developed microvolume inlet for precisely determining quadruple sulfur isotopic composition. Based on pore water chemistry and temperature profile, the subseafloor environment are divided into Unit-1, -2 and -3 with depth below surface. In Unit-1 (0-10 mbsf), fresh seawater is circulated, whereas in Unit-3 (>40 mbsf), hot hydrothermal fluid (>150 degrees Celsius) is stored below anhydrite cap. The Unit-2 is the mixing zone between the hydrothermal fluid and seawater. We found that the δ34S value of sulfate in the mixing zone was higher than those expected by simple mixing between seawater sulfate in Unit-1 (-20‰) and the hydrothermal component in Unit-3 (-16‰). The observed 34S-enrichment and decreased sulfate concentration suggest sulfate reduction took place in this hydrothermal system. Based on our model calculation assuming the mixing and reduction, apparent isotope effect for 33ɛ, 34ɛ and 36ɛ are estimated to be -16.5‰, -32.2

  8. Shallow Water Hydrothermal Vents in the Gulf of California: Natural Laboratories for Multidisciplinary Research

    NASA Astrophysics Data System (ADS)

    Forrest, M.; Hilton, D. R.; Price, R. E.; Kulongoski, J. T.

    2015-12-01

    Modern and fossil examples of shallow water submarine hydrothermal vents occur throughout the Gulf of California. These sites offer important information about the processes involved in the extensional tectonics that created the Gulf of California and continue to shape the region to this day. Due to their accessibility, shallow water marine hydrothermal vents are far easier to access and study than their deeper analogs, and these settings can provide natural laboratories to study biogeochemical processes. Certain biogeochemical and biomineralizing processes occurring at shallow vents are very similar to those observed around deep-sea hydrothermal vents. In some cases, authigenic carbonates form around shallow vents. However, the hydrothermal precipitates are generally composed of Fe-oxyhydroxides, Mn-oxides, opal, calcite, pyrite and cinnabar, and their textural and morphological characteristics suggest microbial mediation for mineral deposition. Modern shallow-water hydrothermal vents also support complex biotic communities, characterized by the coexistence of chemosynthetic and photosynthetic organisms. These shallow vents are highly productive and provide valuable resources to local fishermen. Extant shallow water hydrothermal activity has been studied in Bahía Concepción, San Felipe, Punta Estrella, El Coloradito, Puertecitos, and around the Islas Encantadas. Discrete streams of gas bubbles are often discharged along with hot liquids at shallow water vents. The vent liquids generally exhibit lower salinities than seawater, and their isotopic compositions indicate that they contain meteoric water mixed with seawater. The composition of the shallow vent gas is primarily made up of CO2, but may also be enriched in N2, H2S, CH4, and other higher hydrocarbons. The geochemistry of these gases can be informative in determining the sources and processes involved in their generation. In particular, 3He/4He ratios may provide valuable information about the origin of

  9. Hydrothermal systems in small ocean planets.

    PubMed

    Vance, Steve; Harnmeijer, Jelte; Kimura, Jun; Hussmann, Hauke; Demartin, Brian; Brown, J Michael

    2007-12-01

    We examine means for driving hydrothermal activity in extraterrestrial oceans on planets and satellites of less than one Earth mass, with implications for sustaining a low level of biological activity over geological timescales. Assuming ocean planets have olivine-dominated lithospheres, a model for cooling-induced thermal cracking shows how variation in planet size and internal thermal energy may drive variation in the dominant type of hydrothermal system-for example, high or low temperature system or chemically driven system. As radiogenic heating diminishes over time, progressive exposure of new rock continues to the current epoch. Where fluid-rock interactions propagate slowly into a deep brittle layer, thermal energy from serpentinization may be the primary cause of hydrothermal activity in small ocean planets. We show that the time-varying hydrostatic head of a tidally forced ice shell may drive hydrothermal fluid flow through the seafloor, which can generate moderate but potentially important heat through viscous interaction with the matrix of porous seafloor rock. Considering all presently known potential ocean planets-Mars, a number of icy satellites, Pluto, and other trans-neptunian objects-and applying Earth-like material properties and cooling rates, we find depths of circulation are more than an order of magnitude greater than in Earth. In Europa and Enceladus, tidal flexing may drive hydrothermal circulation and, in Europa, may generate heat on the same order as present-day radiogenic heat flux at Earth's surface. In all objects, progressive serpentinization generates heat on a globally averaged basis at a fraction of a percent of present-day radiogenic heating and hydrogen is produced at rates between 10(9) and 10(10) molecules cm(2) s(1).

  10. Hydrothermal systems in small ocean planets.

    PubMed

    Vance, Steve; Harnmeijer, Jelte; Kimura, Jun; Hussmann, Hauke; Demartin, Brian; Brown, J Michael

    2007-12-01

    We examine means for driving hydrothermal activity in extraterrestrial oceans on planets and satellites of less than one Earth mass, with implications for sustaining a low level of biological activity over geological timescales. Assuming ocean planets have olivine-dominated lithospheres, a model for cooling-induced thermal cracking shows how variation in planet size and internal thermal energy may drive variation in the dominant type of hydrothermal system-for example, high or low temperature system or chemically driven system. As radiogenic heating diminishes over time, progressive exposure of new rock continues to the current epoch. Where fluid-rock interactions propagate slowly into a deep brittle layer, thermal energy from serpentinization may be the primary cause of hydrothermal activity in small ocean planets. We show that the time-varying hydrostatic head of a tidally forced ice shell may drive hydrothermal fluid flow through the seafloor, which can generate moderate but potentially important heat through viscous interaction with the matrix of porous seafloor rock. Considering all presently known potential ocean planets-Mars, a number of icy satellites, Pluto, and other trans-neptunian objects-and applying Earth-like material properties and cooling rates, we find depths of circulation are more than an order of magnitude greater than in Earth. In Europa and Enceladus, tidal flexing may drive hydrothermal circulation and, in Europa, may generate heat on the same order as present-day radiogenic heat flux at Earth's surface. In all objects, progressive serpentinization generates heat on a globally averaged basis at a fraction of a percent of present-day radiogenic heating and hydrogen is produced at rates between 10(9) and 10(10) molecules cm(2) s(1). PMID:18163874

  11. Hydrothermal Fluxes in Europan Ocean: The Effect of Seawater and Oceanic Crust Composition

    NASA Astrophysics Data System (ADS)

    Foustoukos, D.; Seyfried, W.

    2005-12-01

    The recent discovery of electrolyte-enriched liquid water layer in Jupiter icy satellite, Europa, has triggered numerous investigations to assess the chemical composition and physicochemical processes occurring within Europan ocean. Europa appears to be strongly differentiated composed by a metallic core and a hydrated silicate mantle. Thus, heat fluxes could be generated in the planetary core through radioactive decay stimulating volcanic events and serving as the driving force for subseafloor hydrothermal activity. Beyond doubt, the chemical composition of the seawater and the oceanic substrate on Europa plays a key role in regulating pH and redox reactions during presumed hydrothermal alteration processes. Hydrothermal alteration of basalt and peridotite, for example, will likely yield different pH conditions, with the ultramafic-hosted hydrothermal system resulting in higher pH, significantly affecting the ratio of reduced/oxidized sulfur and the metal fluxes. Incipient alteration of basalt and peridotite will also generate reducing conditions, although the H2/H2S ratio of the coexisting fluid will be higher in the ultramafic systems. An important chemical control on Europan ocean evolution is the redox state of the sulfur originated from the oceanic crust and the SO4-enriched neutral-alkaline seawater. In general, relatively alkaline and oxidizing conditions favor the formation of SO4, while more acidic and reducing conditions yield H2S(aq) stable. Thus, hydrothermal alteration of basalt and peridotite facilitates sulfate reduction, while constraints imposed by a more oxidizing mineral assemblage (e.g. hematite-magnetite-pyrite) would render low H2(aq) conditions inhibiting formation of reduced sulfate species. Extensive hydrothermal alteration of fresh basalt, however, forming epidote and anhydrite, would preclude phase equilibria involving hematite. Consequently, initial neutral pH would be shifted towards more acidic conditions, limiting by this way any

  12. Fungal colonization of an Ordovician impact-induced hydrothermal system

    NASA Astrophysics Data System (ADS)

    Ivarsson, Magnus; Broman, Curt; Sturkell, Erik; Ormö, Jens; Siljeström, Sandra; van Zuilen, Mark; Bengtson, Stefan

    2013-12-01

    Impacts are common geologic features on the terrestrial planets throughout the solar system, and on at least Earth and Mars impacts have induced hydrothermal convection. Impact-generated hydrothermal systems have been suggested to possess the same life supporting capability as hydrothermal systems associated with volcanic activity. However, evidence of fossil microbial colonization in impact-generated hydrothermal systems is scarce in the literature. Here we report of fossilized microorganisms in association with cavity-grown hydrothermal minerals from the 458 Ma Lockne impact structure, Sweden. Based on morphological characteristics the fossilized microorganisms are interpreted as fungi. We further infer the kerogenization of the microfossils, and thus the life span of the fungi, to be contemporaneous with the hydrothermal activity and migration of hydrocarbons in the system. Our results from the Lockne impact structure show that hydrothermal systems associated with impact structures can support colonization by microbial life.

  13. Fungal colonization of an Ordovician impact-induced hydrothermal system

    PubMed Central

    Ivarsson, Magnus; Broman, Curt; Sturkell, Erik; Ormö, Jens; Siljeström, Sandra; van Zuilen, Mark; Bengtson, Stefan

    2013-01-01

    Impacts are common geologic features on the terrestrial planets throughout the solar system, and on at least Earth and Mars impacts have induced hydrothermal convection. Impact-generated hydrothermal systems have been suggested to possess the same life supporting capability as hydrothermal systems associated with volcanic activity. However, evidence of fossil microbial colonization in impact-generated hydrothermal systems is scarce in the literature. Here we report of fossilized microorganisms in association with cavity-grown hydrothermal minerals from the 458 Ma Lockne impact structure, Sweden. Based on morphological characteristics the fossilized microorganisms are interpreted as fungi. We further infer the kerogenization of the microfossils, and thus the life span of the fungi, to be contemporaneous with the hydrothermal activity and migration of hydrocarbons in the system. Our results from the Lockne impact structure show that hydrothermal systems associated with impact structures can support colonization by microbial life. PMID:24336641

  14. Fungal colonization of an Ordovician impact-induced hydrothermal system.

    PubMed

    Ivarsson, Magnus; Broman, Curt; Sturkell, Erik; Ormö, Jens; Siljeström, Sandra; van Zuilen, Mark; Bengtson, Stefan

    2013-12-16

    Impacts are common geologic features on the terrestrial planets throughout the solar system, and on at least Earth and Mars impacts have induced hydrothermal convection. Impact-generated hydrothermal systems have been suggested to possess the same life supporting capability as hydrothermal systems associated with volcanic activity. However, evidence of fossil microbial colonization in impact-generated hydrothermal systems is scarce in the literature. Here we report of fossilized microorganisms in association with cavity-grown hydrothermal minerals from the 458 Ma Lockne impact structure, Sweden. Based on morphological characteristics the fossilized microorganisms are interpreted as fungi. We further infer the kerogenization of the microfossils, and thus the life span of the fungi, to be contemporaneous with the hydrothermal activity and migration of hydrocarbons in the system. Our results from the Lockne impact structure show that hydrothermal systems associated with impact structures can support colonization by microbial life.

  15. Fungal colonization of an Ordovician impact-induced hydrothermal system.

    PubMed

    Ivarsson, Magnus; Broman, Curt; Sturkell, Erik; Ormö, Jens; Siljeström, Sandra; van Zuilen, Mark; Bengtson, Stefan

    2013-01-01

    Impacts are common geologic features on the terrestrial planets throughout the solar system, and on at least Earth and Mars impacts have induced hydrothermal convection. Impact-generated hydrothermal systems have been suggested to possess the same life supporting capability as hydrothermal systems associated with volcanic activity. However, evidence of fossil microbial colonization in impact-generated hydrothermal systems is scarce in the literature. Here we report of fossilized microorganisms in association with cavity-grown hydrothermal minerals from the 458 Ma Lockne impact structure, Sweden. Based on morphological characteristics the fossilized microorganisms are interpreted as fungi. We further infer the kerogenization of the microfossils, and thus the life span of the fungi, to be contemporaneous with the hydrothermal activity and migration of hydrocarbons in the system. Our results from the Lockne impact structure show that hydrothermal systems associated with impact structures can support colonization by microbial life. PMID:24336641

  16. Near- and supercritical ethanol treatment of biocrude from hydrothermal liquefaction of microalgae.

    PubMed

    Yang, Le; Li, Yongdan; Savage, Phillip E

    2016-07-01

    Biocrude produced from algae by hydrothermal liquefaction was treated with near- and supercritical ethanol and ethanol-water mixtures at 210-290°C for 0.5-4h. Longer reaction times and higher temperatures better promoted esterification reactions. Dilution of the ethanol with water led to lower yields of treated biocrude and reduced ester content. The viscosity of treated biocrude was an order of magnitude lower than that of the crude bio-oil, and the treated biocrude exhibited the characteristics of a Newtonian fluid. Overall, treatment of biocrude with near- and supercritical ethanol generated a treated bio-oil with lower viscosity, more ester content, and in nearly 100wt% yield. PMID:27055767

  17. Method validation and simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with 7,12 dimethylbenz[a]anthracene and Plantago major L. by high- performance liquid chromatography using diode-array detection.

    PubMed

    Levent, Abdulkadi; Oto, Gokhan; Ekin, Suat; Berber, Ismet

    2013-02-01

    A new and simple high-performance liquid chromatography method was developed and validated for the simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with Plantago Major L. and 7,12 dimethylbenz[a]anthracene. High-performance liquid chromatography analysis was performed utilizing an Inertsil ODS3 reversed phase column with methanol-tetrahydrofuran-water as mobile phase under gradient conditions, at 1.5 mL min(-1) flow rate and 25 °C. Diode-array detection was at 325, 450, 290 and 270 nm (retinol and retinyl palmitate), β-carotene, α-tocopherol and vitamin C, respectively and runnig time 18 min. The high-performance liquid chromatography assay and extraction procedure proposed are simple, rapid, sensitive and accurate. The method was then applied for the determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum. Results of this study demonstrated that; at 60th day DMBA-treated group, there was a significant decrease in vitamin levels compared to the levels of control group. A significant increase was observed in vitamin levels of 7,12 dimethylbenz[α]anthracene+Plantago Major L.-treated group compared to the DMBA-treated group. Additionally, the results obtained in the study are found to be in agreement with data reported in the literature. PMID:23176060

  18. Method validation and simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with 7,12 dimethylbenz[a]anthracene and Plantago major L. by high- performance liquid chromatography using diode-array detection.

    PubMed

    Levent, Abdulkadi; Oto, Gokhan; Ekin, Suat; Berber, Ismet

    2013-02-01

    A new and simple high-performance liquid chromatography method was developed and validated for the simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with Plantago Major L. and 7,12 dimethylbenz[a]anthracene. High-performance liquid chromatography analysis was performed utilizing an Inertsil ODS3 reversed phase column with methanol-tetrahydrofuran-water as mobile phase under gradient conditions, at 1.5 mL min(-1) flow rate and 25 °C. Diode-array detection was at 325, 450, 290 and 270 nm (retinol and retinyl palmitate), β-carotene, α-tocopherol and vitamin C, respectively and runnig time 18 min. The high-performance liquid chromatography assay and extraction procedure proposed are simple, rapid, sensitive and accurate. The method was then applied for the determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum. Results of this study demonstrated that; at 60th day DMBA-treated group, there was a significant decrease in vitamin levels compared to the levels of control group. A significant increase was observed in vitamin levels of 7,12 dimethylbenz[α]anthracene+Plantago Major L.-treated group compared to the DMBA-treated group. Additionally, the results obtained in the study are found to be in agreement with data reported in the literature.

  19. Hydrothermal Activity on ultraslow Spreading Ridge: new hydrothermal fields found on the Southwest Indian ridge

    NASA Astrophysics Data System (ADS)

    Tao, C.; Li, H.; Deng, X.; Lei, J.; Wang, Y.; Zhang, K.; Zhou, J.; Liu, W.

    2014-12-01

    Ultraslow spreading ridge makes up about 25% of global mid-ocean ridge length. Previous studies believed that hydrothermal activity is not widespread on the ultraslow spreading ridge owing to lower magma supply. Southwest Indian ridge (SWIR) with the spreading rate between 1.2cm/a to 1.4cm/a, represents the ultraslow spreading ridge. In 2007, Chinese Cruise (CC) 19th discovered the Dragon Flag deposit (DFD) on the SWIR, which is the first active hydrothermal field found on the ultraslow spreading ridge. In recent years, over 10 hydrothermal fields have been found on the SWIR between Indomed and Gallieni transform faults by the Chinese team. Tao et al. (2012) implied that the segment sections with excess heat from enhanced magmatism and suitable crustal permeability along slow and ultraslow ridges might be the most promising areas for searching for hydrothermal activities. In 2014, CC 30thdiscovered five hydrothermal fields and several hydrothermal anomalies on the SWIR. Dragon Horn Area (DHA). The DHA is located on the southern of segment 27 SWIR, with an area of about 400 km2. The geophysical studies indicated that the DHA belongs to the oceanic core complex (OCC), which is widespread on the slow spreading ridges (Zhao et al., 2013). The rocks, such as gabbro, serpentinized peridotite, and consolidated carbonate were collected in the DHA, which provide the direct evidence with the existence of the OCC. However, all rock samples gathered by three TV-grab stations are basalts on the top of the OCC. A hydrothermal anomaly area, centered at 49.66°E,37.80° S with a range of several kms, is detected in the DHA. It is probably comprised of several hydrothermal fields and controlled by a NW fault. New discovery of hydrothermal fields. From January to April 2014, five hydrothermal fields were discovered on the SWIR between 48°E to 50°E during the leg 2&3 of the CC 30th, which are the Su Causeway field (48.6°E, 38.1°S), Bai Causeway field (48.8°E, 37.9 °S), Dragon

  20. Treating Sludges

    ERIC Educational Resources Information Center

    Josephson, Julian

    1978-01-01

    Discussed are some of the ways to handle municipal and industrial wastewater treatment sludge presented at the 1978 American Chemical Society meeting. Suggestions include removing toxic materials, recovering metals, and disposing treated sewage sludge onto farm land. Arguments for and against land use are also given. (MA)

  1. Hydrothermal carbonisation of sewage sludge: effect of process conditions on product characteristics and methane production.

    PubMed

    Danso-Boateng, E; Shama, G; Wheatley, A D; Martin, S J; Holdich, R G

    2015-02-01

    Hydrothermal carbonisation of primary sewage sludge was carried out using a batch reactor. The effect of temperature and reaction time on the characteristics of solid (hydrochar), liquid and gas products, and the conditions leading to optimal hydrochar characteristics were investigated. The amount of carbon retained in hydrochars decreased as temperature and time increased with carbon retentions of 64-77% at 140 and 160°C, and 50-62% at 180 and 200°C. Increasing temperature and treatment time increased the energy content of the hydrochar from 17 to 19 MJ/kg but reduced its energy yield from 88% to 68%. Maillard reaction products were identified in the liquid fractions following carbonisations at 180 and 200°C. Theoretical estimates of the methane yields resulting from the anaerobic digestion of the liquid by-products are also presented and optimal reaction conditions to maximise these identified.

  2. Strong cellulase inhibitors from the hydrothermal pretreatment of wheat straw

    PubMed Central

    2013-01-01

    Background The use of the enzymatic hydrolysis of lignocellulose with subsequent fermentation to ethanol provides a green alternative for the production of transportation fuels. Because of its recalcitrant nature, the lignocellulosic biomass must be pretreated before enzymatic hydrolysis. However, the pretreatment often results in the formation of compounds that are inhibitory for the enzymes or fermenting organism. Although well recognized, little quantitative information on the inhibition of individual cellulase components by identified inhibitors is available. Results Strong cellulase inhibitors were separated from the liquid fraction of the hydrothermal pretreatment of wheat straw. HPLC and mass-spectroscopy analyses confirmed that the inhibitors were oligosaccharides (inhibitory oligosaccharides, IOS) with a degree of polymerization from 7 to 16. The IOS are composed of a mixture of xylo- (XOS) and gluco-oligosaccharides (GOS). We propose that XOS and GOS are the fragments of the xylan backbone and mixed-linkage β-glucans, respectively. The IOS were approximately 100 times stronger inhibitors for Trichoderma reesei cellobiohydrolases (CBHs) than cellobiose, which is one of the strongest inhibitors of these enzymes reported to date. Inhibition of endoglucanases (EGs) by IOS was weaker than that of CBHs. Most of the tested cellulases and hemicellulases were able to slowly degrade IOS and reduce the inhibitory power of the liquid fraction to some extent. The most efficient single enzyme component here was T. reesei EG TrCel7B. Although reduced by the enzyme treatment, the residual inhibitory power of IOS and the liquid fraction was strong enough to silence the major component of the T. reesei cellulase system, CBH TrCel7A. Conclusions The cellulase inhibitors described here may be responsible for the poor yields from the enzymatic conversion of the whole slurries from lignocellulose pretreatment under conditions that do not favor complete degradation of

  3. Hydrothermal Detoxization of Slate Containing Asbestos and the Possibility of Application for Fertilizer of its Products

    SciTech Connect

    Myojin, Sachi; Yamasaki, Chizuko; Yamasaki, Nakamichi; Kuroki, Toshihiro; Manabe, Wataru

    2010-11-24

    Hydrothermal decomposition of slate (building materials) containing asbestos has been attempted by using a NH{sub 4}H{sub 2}PO{sub 4} solution. Firstly, the alteration of chrysotile as a starting material was investigated under hydrothermal conditions of 200 deg. C, 12 hrs of reaction time and with a phosphate solution. It was confirmed that the original fibrous form of chrysotile had been perfectly collapsed by the SEM observation. The chrysotile (asbestos) disappeared to form Mg-Ca-Silicate (Ca{sub 7}Mg{sub 2}P{sub 6}O{sup 24}) estimated by XRD. The composition and chemical form of reaction products (Mg-Ca-Silicate) was predicted to application as a fertilizer. Fertilizer effect of these resulted product on cultivations of Japanese radish (leaves), soybeans and tomatoes, was examined by using a special medium of mixed soil with a low content of N, P, K and a thermal-treated zeolite one. The fertilizer effects of the product were compared to commercial fertilizers such as N, N-K-P and P types. In order to estimate the fertilizer effect, the size of crops, number of fruits and number of leaves were measured everyday. As a result, these hydrothermal products of slate containing asbestos were as good as commercial fertilizers on the market. Fruits groups especially had a good crop using the hydrothermal slate product. These results show that the main components of hydrothermal treatments slate are calcium silicate and magnesium phosphate. Its decomposition reaction products may have the possibility of application for fertilization of crops which require nucleic acid--phosphorus.

  4. Hydrothermal Detoxization of Slate Containing Asbestos and the Possibility of Application for Fertilizer of its Products

    NASA Astrophysics Data System (ADS)

    Myojin, Sachi; Kuroki, Toshihiro; Manabe, Wataru; Yamasaki, Chizuko; Yamasaki, Nakamichi

    2010-11-01

    Hydrothermal decomposition of slate (building materials) containing asbestos has been attempted by using a NH4H2PO4 solution. Firstly, the alteration of chrysotile as a starting material was investigated under hydrothermal conditions of 200° C, 12 hrs of reaction time and with a phosphate solution. It was confirmed that the original fibrous form of chrysotile had been perfectly collapsed by the SEM observation. The chrysotile (asbestos) disappeared to form Mg-Ca-Silicate (Ca7Mg2P6O24) estimated by XRD. The composition and chemical form of reaction products (Mg-Ca-Silicate) was predicted to application as a fertilizer. Fertilizer effect of these resulted product on cultivations of Japanese radish (leaves), soybeans and tomatoes, was examined by using a special medium of mixed soil with a low content of N, P, K and a thermal-treated zeolite one. The fertilizer effects of the product were compared to commercial fertilizers such as N, N-K-P and P types. In order to estimate the fertilizer effect, the size of crops, number of fruits and number of leaves were measured everyday. As a result, these hydrothermal products of slate containing asbestos were as good as commercial fertilizers on the market. Fruits groups especially had a good crop using the hydrothermal slate product. These results show that the main components of hydrothermal treatments slate are calcium silicate and magnesium phosphate. Its decomposition reaction products may have the possibility of application for fertilization of crops which require nucleic acid—phosphorus.

  5. Evidence for Hydrothermal Vents as "Biogeobatteries" (Invited)

    NASA Astrophysics Data System (ADS)

    Nielsen, M. E.; Girguis, P. R.

    2010-12-01

    Hydrothermal vents are unique systems that play an important role in oceanic biogeochemical cycles. As chemically reduced hydrothermal fluid mixes with cold oxic seawater, minerals precipitate out of solution resulting in chimney structures composed largely of metal sulfides and anhydrite. Pyrite, which is a natural semi-conductor, is the primary sulfide mineral, but other minerals within chimneys are also conductive (e.g. chalcopyrite, wurtzite, and some iron oxides). Sulfide chimneys are also known to host an extensive endolithic microbial community. Accordingly, submarine hydrothermal systems appear to be examples of biogeobatteries, wherein conductive mineral assemblages span naturally occuring redox gradients and enable anaerobic microbes to access oxygen as an oxidant via extracellular electron transfer (or EET). To test this hypothesis, we ran a series of electrochemical laboratory experiments in which pyrite was used as an anode (in a vessel flushed with hydrothermal-like fluid). When placed in continuity with a carbon fiber cathode, pyrite was found to accept and conduct electrons from both abiotic and biological processes (microbial EET). Specifically, electrical current increased 4-fold (5 nA/m2 to 20 nA/m2) in response to inoculation with a slurry prepared from a hydrothermal vent sample. Inspection of the pyrite anode with SEM revealed ubiquitous coverage by microbes. DNA was extracted from the anodes and the inoculum, and was subjected to pyrosequencing to examine prokaryotic diversity. These data suggest that key microbial phylotypes were enriched upon the pyrite, implicating them in EET. In addition, we deployed an in situ experiment based on microbial fuel cell architecture with a graphite anode inserted into a vent wall coupled to a carbon fiber cathode outside the vent. We observed current production over the course of one year, implying microbial EET in situ. Via pyrosequencing, we observed that the microbial community on the anode was

  6. Kinetic study of phase transformation of n-octane using hydrothermal diamond anvil cell

    NASA Astrophysics Data System (ADS)

    Liu, Chuanjiang; Zheng, Haifei; Wang, Duojun

    2016-02-01

    A kinetic study of phase transformation of n-octane has been performed using a hydrothermal diamond anvil cell. The results show that pressure has a negative effect on the solid-liquid reaction rate. The increase of pressure can accelerate the liquid-solid transformation rate. Upon the liquid-solid transformation, the light transmittance showed a decreased trend with time in the early stage, which was caused by the formation of a large quantity of crystal nuclei. In the later stage, the light transmittance almost remained the same, thus indicating a growth stage of crystal nuclei. The activation volume yields a value of 2.16×10-5 and -1.35×10-5 m3/mol for the solid-liquid and liquid-solid transformations. Based on the obtained activation energy, the solid-liquid transformation is dominated by the interfacial reaction and diffusion, and the liquid-solid transformation is controlled by diffusion. This technique is an effective and powerful tool for the transformation kinetics study of n-octane.

  7. Hydrothermal brecciation in the Jemez Fault zone, Valles Caldera, New Mexico: Results from CSDP (Continental Scientific Drilling Program) corehole VC-1

    SciTech Connect

    Hulen, J.B.; Nielson, D.L.

    1987-06-01

    Paleozoic and Precambrian rocks intersected deep in Continental Scientific Drilling Program corehole VC-1, adjacent to the late Cenozoic Valles caldera complex, have been disrupted to form a spectacular breccia sequence. The breccias are of both tectonic and hydrothermal origin, and probably formed in the Jemez fault zone, a major regional structure with only normal displacement since mid-Miocene. Tectonic breccias are contorted, crushed, sheared, and granulated; slickensides are commmon. Hydrothermal breccias, by contrast, lack these frictional textures, but arej commonly characterized by fluidized matrix foliation and prominent clast rounding. Fluid inclusions in the hydrothermal breccias are dominantly two-phase, liquid-rich at room temperature, principally secondary, and form two distinctly different compositional groups. Older inclusions, unrelated to brecciation, are highly saline and homogenize to the liquid phase in the temperature range 189 to 246/sup 0/C. Younger inclusions, in part of interbreccia origin, are low-salinity and homogenize (also to liquid) in the range 230 to 283/sup 0/C. Vapor-rich inclusions locally trapped along with these dilute liquid-rich inclusions document periodic boiling. These fluid-inclusion data, together with alteration assemblages and textures as well as the local geologic history, have been combined to model hydrothermal brecciation at the VC-1 site.

  8. Hydrothermal treatment of titanium alloys for the enhancement of osteoconductivity.

    PubMed

    Zuldesmi, Mansjur; Waki, Atsushi; Kuroda, Kensuke; Okido, Masazumi

    2015-04-01

    The surface wettability of implants is a crucial factor in their osteoconductivity because it influences the adsorption of cell-attached proteins onto the surface. In this study, a single-step hydrothermal surface treatment using distilled water at a temperature of 180°C for 3h was applied to titanium (Ti) and its alloys (Ti-6Al-4V, Ti-6Al-7Nb, Ti-29Nb-13Ta-4.6Zr, Ti-13Cr-1Fe-3Al; mass%) and compared with as-polished Ti implants and with implants produced by anodizing Ti in 0.1M of H3PO4 with applied voltages from 0V to 150V at a scanning rate of 0.1Vs(-1). The surface-treated samples were stored in a five time phosphate buffered saline (×5 PBS(-)) solution to prevent increasing the water contact angle (WCA) with time. The surface characteristics were evaluated using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Auger electron spectroscopy, surface roughness, and contact angle measurement using a 2μL droplet of distilled water. The relationship between WCA and osteoconductivity at various surface modifications was examined using in vivo tests. The results showed that a superhydrophilic surface with a WCA≤10° and a high osteoconductivity (RB-I) of up to 50% in the cortical bone part, about four times higher than the as-polished Ti and Ti alloys, were provided by the combination of the hydrothermal surface treatment and storage in ×5 of PBS(-).

  9. Removal of trace elements in hydrothermal plume at submarine volcanic arc hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Shitashima, K.

    2007-12-01

    On the study of geochemical fluxes of trace elements from the hydrothermal system, it is necessary to collect not only samples by the hydro-cast from surface ship and fluid samples using a submersible but also temporally and spatially continuous samples ranging from a fluid to a hydrothermal plume. For that purpose, the sampling method along the diluting and rising plume just after erupting from a hydrothermal vent is effective. The mini CTDT-RMS was installed onto the submersible. The hydrothermal plume samples were collected with monitoring the anomalies of temperature and turbidity by taking the distance from the hydrothermal vent gradually. Unfiltered sample for total (particulate + dissolved) trace element concentration and filtered sample for dissolved trace element concentration were analyzed on land. In V, Ni, Cu, Mo, Cd, Pb and Zn, particulate form was predominant in the fluid. The elements that are easy to form a sulfide such as Cu, Cd and Pb were removed as a sulfide precipitate from the fluid before erupting to the deep ocean. Therefore, the concentration of these trace elements in the hydrothermal plume showed superiority of a dissolved form, and was slightly high or same concentration in the deep ocean. The concentration of Fe in the fluid was extremely higher (500 - 100,000 times) than that in the deep ocean, and showed a fifty-fifty partition between dissolved form and particulate form. In the hydrothermal plume, Fe formed hydroxide mainly and was removed gradually from the plume as a particulate form in dilution and diffusion process of the plume. These hydroxides may play a role of the precipitant that coprecipitate with absorbing the other trace elements. Because Mn is hard to deposit as a sulfide, dissolved form was predominant in the fluid and Mn showed extreme high concentration same as Fe. Mn was discharged to the deep ocean as a dissolved form and removed from the plume as an oxide with increasing the particulate form gradually in dilution

  10. Process Development for Hydrothermal Liquefaction of Algae Feedstocks in a Continuous-Flow Reactor

    SciTech Connect

    Elliott, Douglas C.; Hart, Todd R.; Schmidt, Andrew J.; Neuenschwander, Gary G.; Rotness, Leslie J.; Olarte, Mariefel V.; Zacher, Alan H.; Albrecht, Karl O.; Hallen, Richard T.; Holladay, Johnathan E.

    2013-10-01

    Wet algae slurries can be converted into an upgradeable biocrude by hydrothermal liquefaction (HTL). High levels of carbon conversion to gravity-separable biocrude product were accomplished at relatively low temperature (350 °C) in a continuous-flow, pressurized (sub-critical liquid water) environment (20 MPa). As opposed to earlier work in batch reactors reported by others, direct oil recovery was achieved without the use of a solvent and biomass trace components were removed by processing steps so that they did not cause process difficulties. High conversions were obtained even with high slurry concentrations of up to 35 wt% of dry solids. Catalytic hydrotreating was effectively applied for hydrodeoxygenation, hydrodenitrogenation, and hydrodesulfurization of the biocrude to form liquid hydrocarbon fuel. Catalytic hydrothermal gasification was effectively applied for HTL byproduct water cleanup and fuel gas production from water soluble organics, allowing the water to be considered for recycle of nutrients to the algae growth ponds. As a result, high conversion of algae to liquid hydrocarbon and gas products was found with low levels of organic contamination in the byproduct water. All three process steps were accomplished in bench-scale, continuous-flow reactor systems such that design data for process scale-up was generated.

  11. Iridium material for hydrothermal oxidation environments

    DOEpatents

    Hong, Glenn T.; Zilberstein, Vladimir A.

    1996-01-01

    A process for hydrothermal oxidation of combustible materials in which, during at least a part of the oxidation, corrosive material is present and makes contact with at least a portion of the apparatus over a contact area on the apparatus. At least a portion of the contact surface area comprises iridium, iridium oxide, an iridium alloy, or a base metal overlaid with an iridium coating. Iridium has been found to be highly resistant to environments encountered in the process of hydrothermal oxidation. Such environments typically contain greater than 50 mole percent water, together with oxygen, carbon dioxide, and a wide range of acids, bases and salts. Pressures are typically about 27.5 to about 1000 bar while temperatures range as high as 800.degree. C.

  12. Colorado's hydrothermal resource base: an assessment

    SciTech Connect

    Pearl, R.H.

    1981-01-01

    As part of its effort to more accurately describe the nations geothrmal resource potential, the US Department of Energy/Division of Geothermal Energy contracted with the Colorado Geological survey to appraise the hydrothermal (hot water) geothermal resources of Colorado. Part of this effort required that the amount of energy that could possibly be contained in the various hydrothermal systems in Colorado be estimated. The findings of that assessment are presented. To make these estimates the geothermometer reservoir temperatures estimated by Barrett and Pearl (1978) were used. In addition, the possible reservoir size and extent were estimated and used. This assessment shows that the total energy content of the thermal systems in Colorado could range from 4.872 x 10{sup 15} BTU's to 13.2386 x 10{sup 15} BTU's.

  13. Whole Algae Hydrothermal Liquefaction Technology Pathway

    SciTech Connect

    Biddy, Mary J.; Davis, Ryan; Jones, Susanne B.; Zhu, Yunhua

    2013-03-31

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates the feasibility of using whole wet microalgae as a feedstock for conversion via hydrothermal liquefaction. Technical barriers and key research needs have been assessed in order for the hydrothermal liquefaction of microalgae to be competitive with petroleum-derived gasoline, diesel and jet range blendstocks.

  14. Hydrothermal reactions of fly ash. [Quarterly] report, April 1, 1993--June 31, 1993

    SciTech Connect

    Brown, P.W.

    1993-09-01

    Reactions which occur when fly ash is treated under hydrothermal conditions are being investigated, in order to determine the nature of the phases that form, assess the stabilities of these phases in the ambient environment and, finally, assess whether these phases are capable of sequestering hazardous species. Another reason for undertaken this proposed study is that, depending on the composition of the ash and the presence of selected additives, it may be possible under hydrothermal conditions to form compounds which have cementitious properties. Formation of four classes of compounds, which bracket likely fly ash compositional ranges. have been selected for study: calcium silicate hydrates, calcium silicosulfates, calcium aluminosulfates, and alkali aluminosilicates. Hydration of tricalcium aluminate in presence of Sr(OH){sub 2} or SeO{sub 2}, and of fly ash with Ca(OH){sub 2} and CaSO{sub 4}, 2H{sub 2}O was carried out and the product and pure structure analyzed.

  15. How Is Thrombotic Thrombocytopenic Purpura Treated?

    MedlinePlus

    ... and surgery. Treatments are done in a hospital. Plasma Therapy Plasma is the liquid part of your blood. It ... nutrients to your body. TTP is treated with plasma therapy. This includes: Fresh frozen plasma for people ...

  16. Modeling Microbiological Interactions with Hydrothermal Flow

    NASA Technical Reports Server (NTRS)

    Hoehler, Tori

    2006-01-01

    All organisms require energy. Characterizing and quantifying the biological demand for energy places constraints on the possible interactions of organisms with each other and with the environment. This talk will consider energetic and mass transfer constraints on the ecology of hydrothermal vent microbes. Following a general introduction to the biological energy requirements and their link to environmental conditions, energy constraints will be applied to several vent-relevant case studies.

  17. Modeling Hydrothermal Mineralization: Fractal or Multifrcatal Models?

    NASA Astrophysics Data System (ADS)

    Cheng, Q.

    2004-05-01

    Hydrothermal mineralization occurs when the natural geo-processes involve the interaction of ore material-carrying hydrothermal fluids with rocks in the earth's crust in a specific geological environment. Mineralization can cause element concentration enrichment or depletion in the country rocks. Local enrichment may form ore body that can be mined for profit at the current economic and technological conditions. To understand the spatial distribution of element concentration enrichment or depletion caused by mineralization in a mineral district is essential for mineral exploration and mineral prediction. Grade-tonnage model and mineral deposits size distribution model are common models used for characterizing mineral deposits. This paper proposes a non-linear mineralization model on the basis of a modified classical igneous differentiation mineralization model to describe the generation of multifractal distribution of element concentration in the country rocks as well as grade-tonnage fractal/multifractal distribution of ore deposits that have been often observed in hydrothermal mineralization. This work may also lead to a singularity model to explain the common properties of mineralization and mineralization-associated geochemical anomaly diversity and the generalized self-similarity of the anomalies. The model has been applied to a case study of mineral deposits prediction and mineral resource assessment in the Abitibi district, northern Ontario, Canada.

  18. Diffuse flow from hydrothermal vents. Doctoral thesis

    SciTech Connect

    Trivett, D.A.

    1991-08-01

    The effluent from a collection of diffuse hydrothermal vents was modelled to determine the fate of the source of flow under typical environmental conditions at seafloor spreading centers. A laboratory simulation was conducted to test an analytic model of diffuse plume rise. The results showed that diffuse plumes are likely to remain near the seafloor, with their maximum rise height scaled with the diameter of the source of diffuse flow. The entrainment of ambient seawater into these plumes is limited by the proximity to the seafloor, thus slowing the rate of dilution. The model of diffuse plume behaviour was used to guide the design and implementation of a scheme for monitoring the flow from diffuse hydrothermal vents in the ocean. A deployment of an array at the Southern Juan de Fuca Ridge yielded measurements of a variety of diffuse plume properties, including total heat output. Two distinct sources of hydrothermal flow were detected during the field deployment. The larger source was 1-1.5km north of the instrument array, and its energy output was 450 + or - 270MW. A smaller source was located 100m east of one instrument in the array. The energy output of the source was 12 + or - 8MW. The rise heights of the centerlines of these plumes were 45m and 10m, respectively.

  19. Hydrothermal Formation of Calcium Copper Tetrasilicate.

    PubMed

    Johnson-McDaniel, Darrah; Comer, Sara; Kolis, Joseph W; Salguero, Tina T

    2015-12-01

    We describe the first hydrothermal synthesis of CaCuSi4 O10 as micron-scale clusters of thin platelets, distinct from morphologies generated under salt-flux or solid-state conditions. The hydrothermal reaction conditions are surprisingly specific: too cold, and instead of CaCuSi4 O10 , a porous calcium copper silicate forms; too hot, and calcium silicate (CaSiO3 ) forms. The precursors also strongly impact the course of the reaction, with the most common side product being sodium copper silicate (Na2 CuSi4 O10 ). Optimized conditions for hydrothermal CaCuSi4 O10 formation from calcium chloride, copper(II) nitrate, sodium silicate, and ammonium hydroxide are 350 °C at 3000 psi for 72 h; at longer reaction times, competitive delamination and exfoliation causes crystal fragmentation. These results illustrate that CaCuSi4 O10 is an even more unique material than previously appreciated. PMID:26482329

  20. Numerical simulation of magmatic hydrothermal systems

    USGS Publications Warehouse

    Ingebritsen, S.E.; Geiger, S.; Hurwitz, S.; Driesner, T.

    2010-01-01

    The dynamic behavior of magmatic hydrothermal systems entails coupled and nonlinear multiphase flow, heat and solute transport, and deformation in highly heterogeneous media. Thus, quantitative analysis of these systems depends mainly on numerical solution of coupled partial differential equations and complementary equations of state (EOS). The past 2 decades have seen steady growth of computational power and the development of numerical models that have eliminated or minimized the need for various simplifying assumptions. Considerable heuristic insight has been gained from process-oriented numerical modeling. Recent modeling efforts employing relatively complete EOS and accurate transport calculations have revealed dynamic behavior that was damped by linearized, less accurate models, including fluid property control of hydrothermal plume temperatures and three-dimensional geometries. Other recent modeling results have further elucidated the controlling role of permeability structure and revealed the potential for significant hydrothermally driven deformation. Key areas for future reSearch include incorporation of accurate EOS for the complete H2O-NaCl-CO2 system, more realistic treatment of material heterogeneity in space and time, realistic description of large-scale relative permeability behavior, and intercode benchmarking comparisons. Copyright 2010 by the American Geophysical Union.

  1. Surface roughened zirconia: towards hydrothermal stability.

    PubMed

    Camposilvan, Erik; Flamant, Quentin; Anglada, Marc

    2015-07-01

    Surface roughness is needed in several yttria-stabilized zirconia components used in restorative dentistry for osseointegration or adhesion purposes. This can be achieved by different treatments, which may also modify the microstructure of the surface. Among them, sandblasting and chemical etching are widely used, but their effect on hydrothermal aging of zirconia is not fully understood. In the present work, the zirconia long-term stability of rough surfaces prepared by these techniques is analyzed and a method is proposed for preventing hydrothermal aging while maintaining the original surface appearance and mechanical properties. The method involves pressure infiltration of a Cerium salt solution on the roughened surfaces followed by a thermal treatment. The solution, trapped by surface defects and small pores, is decomposed during thermal treatment into Cerium oxide, which is diffused at high temperature, obtaining Ce co-doping in the near-surface region. In addition, the microstructural changes induced in the near-surface by sandblasting or chemical etching are removed by the thermal treatment together with surface defects. No color modification was observed and the final roughness parameters were in the range of existing implants of proved good osseointegration. The aging resistance of Ce co-doped materials was strongly enhanced, showing the absence of aging after artificial degradation, increasing in this way the surface mechanical integrity. The proposed treatment is easily applicable to the current manufacturing procedures of zirconia dental posts, abutments, crowns and dentures, representing a solution to hydrothermal aging in these and other biomedical applications.

  2. Quantitative analysis of the hydrothermal system in Lassen Volcanic National Park and Lassen Known Geothermal Resource Area

    SciTech Connect

    Sorey, M.L.; Ingebritsen, S.E.

    1984-01-01

    The Lassen hydrothermal system is in the southern Cascade Range, approximately 70 kilometers east-southeast of Redding, California. The conceptual model of the Lassen system is termed a liquid-dominated hydrothermal system with a parasitic vapor-dominated zone. The essential feature of this model is that steam and steam-heated discharge at relatively high elevations in Lassen Volcanic National Park (LVNP) and liquid discharge with high chloride concentrations at relatively low elevations outside LVNP in the Lassen Known Geothermal Resource Area (KGRA) are both fed by an upflow of high-enthalpy, two-phase fluid within the Park. Liquid flows laterally away from the upflow area towards the areas of high-chloride discharge, and steam rises through a vapor-dominated zone to feed the steam and steam-heated features. The geometric model corresponds to an areally restricted flow regime that connects the Bumpass Hell area in LVNP with regions of chloride hot springs in the Mill Creek canyon in the KGRA south of LVNP. Simulations of thermal fluid withdrawal in the Mill Creek Canyon were carried out in order to determine the effects of such withdrawal on portions of the hydrothermal system within the Park. 19 refs., 17 figs., 4 tabs.

  3. Isolation of polyphenols from spent coffee grounds and silverskin by mild hydrothermal pretreatment.

    PubMed

    Conde, Teresa; Mussatto, Solange I

    2016-05-18

    In this study, a new method for isolation of polyphenols (PP) from spent coffee grounds (SCG) and coffee silverskin (CS) is described. The method consisted of a mild hydrothermal pretreatment at 120°C, for 20 min, using a liquid-to-solid ratio of 20 mL/g. PP (determined as gallic acid equivalents, GAE) were the most abundant components in the extracts produced by this method, corresponding to 32.92 mgGAE/gSCG and 19.17 mgGAE/gCS, among which flavonoids corresponded to 8.29 and 2.73 mg quercetin equivalents/g of SCG and CS, respectively. Both extracts presented antioxidant activity but the results were higher for SCG extract, probably due to the highest content of PP present. Negligible effects (less than 1% solubilization) were caused by the hydrothermal pretreatment on cellulose, hemicellulose, and protein fractions of these materials. Some mineral elements were present in the extracts, with potassium being the most abundant. Hydrothermal pretreatment under mild conditions was demonstrated to be an efficient method to recover antioxidant PP from coffee residues.

  4. One-step formation of oligopeptide-like molecules from Glu and Asp in hydrothermal environments.

    PubMed

    Kawamura, Kunio; Shimahashi, Masanori

    2008-05-01

    Biopolymer accumulation in the absence of enzymes is an essential step for the chemical evolution of primitive life-like systems, and successful simulation experiments of prebiotic biopolymer formation have suggested that oligopeptides could have formed near submarine hydrothermal vent environments on primitive earth. However, the yield and length of oligopeptides -- typically limited to 6-mers -- seems to be inadequate. One reason is the rapid formation of diketopiperazines (DKPs) from dipeptides. In this study, using a hydrothermal microflow reactor, we show that the one-step synthesis of oligopeptide-like molecules of length up to 20-mers proceeds from Glu and Asp. Yields of up to 0.17-0.57% were obtained in an acidic solution within 183 s at 250-310 degrees C, as evaluated by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis and different types of high-performance liquid chromatography (HPLC) analyses. The present study indicates that Glu and Asp may have played important roles in the chemical evolution of oligopeptide-like molecules in hydrothermal vent environments on primitive earth. PMID:18253712

  5. Dissolved gases in hydrothermal (phreatic) and geyser eruptions at Yellowstone National Park, USA

    USGS Publications Warehouse

    Hurwitz, Shaul; Clor, Laura; McCleskey, R. Blaine; Nordstrom, D Kirk; Hunt, Andrew G.; Evans, William C.

    2016-01-01

    Multiphase and multicomponent fluid flow in the shallow continental crust plays a significant role in a variety of processes over a broad range of temperatures and pressures. The presence of dissolved gases in aqueous fluids reduces the liquid stability field toward lower temperatures and enhances the explosivity potential with respect to pure water. Therefore, in areas where magma is actively degassing into a hydrothermal system, gas-rich aqueous fluids can exert a major control on geothermal energy production, can be propellants in hazardous hydrothermal (phreatic) eruptions, and can modulate the dynamics of geyser eruptions. We collected pressurized samples of thermal water that preserved dissolved gases in conjunction with precise temperature measurements with depth in research well Y-7 (maximum depth of 70.1 m; casing to 31 m) and five thermal pools (maximum depth of 11.3 m) in the Upper Geyser Basin of Yellowstone National Park, USA. Based on the dissolved gas concentrations, we demonstrate that CO2 mainly derived from magma and N2 from air-saturated meteoric water reduce the near-surface saturation temperature, consistent with some previous observations in geyser conduits. Thermodynamic calculations suggest that the dissolved CO2 and N2 modulate the dynamics of geyser eruptions and are likely triggers of hydrothermal eruptions when recharged into shallow reservoirs at high concentrations. Therefore, monitoring changes in gas emission rate and composition in areas with neutral and alkaline chlorine thermal features could provide important information on the natural resources (geysers) and hazards (eruptions) in these areas.

  6. Modes of crustal accretion and their implications for hydrothermal circulation

    NASA Astrophysics Data System (ADS)

    Theissen-Krah, Sonja; Rüpke, Lars H.; Hasenclever, Jörg

    2016-02-01

    Hydrothermal convection at mid-ocean ridges links the ocean's long-term chemical evolution to solid earth processes, forms hydrothermal ore deposits, and sustains the unique chemosynthetic vent fauna. Yet the depth extent of hydrothermal cooling and the inseparably connected question of how the lower crust accretes remain poorly constrained. Here based on coupled models of crustal accretion and hydrothermal circulation, we provide new insights into which modes of lower crust formation and hydrothermal cooling are thermally viable and most consistent with observations at fast-spreading ridges. We integrate numerical models with observations of melt lens depth, thermal structure, and melt fraction. Models matching all these observations always require a deep crustal-scale hydrothermal flow component and less than 50% of the lower crust crystallizing in situ.

  7. Modelling magmatic gas scrubbing in hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Di Napoli, Rossella; Aiuppa, Alessandro; Valenza, Mariano; Bergsson, Baldur; Ilyinskaya, Evgenia; Pfeffer, Melissa Anne; Rakel Guðjónsdóttir, Sylvía

    2015-04-01

    In volcano-hosted hydrothermal systems, the chemistry of deeply rising magmatic gases is extensively modified by gas-water-rock interactions taking place within the hydrothermal reservoir, and/or at shallow groundwaters conditions. These reactions can scrub reactive, water-soluble species (S, halogens) from the magmatic gas phase, so that their quantitative assessment is central to understanding the chemistry of surface gas manifestations, and brings profound implications to the interpretation of volcanic-hydrothermal unrests. Here, we present the results of numerical simulations of magmatic gas scrubbing, in which the reaction path modelling approach (Helgeson, 1968) is used to reproduce hydrothermal gas-water-rock interactions at both shallow (temperature up to 109°C; low-T model runs) and deep reservoir (temperature range: 150-250 °C; high-T model runs) conditions. The model was built based upon the EQ3/6 software package (Wolery and Daveler, 1992), and consisted into a step by step addition of a high-temperature magmatic gas to an initial meteoric water, in the presence of a dissolving aquifer rock. The model outputted, at each step of gas addition, the chemical composition of a new aqueous solution formed after gas-water-rock interactions; which, upon reaching gas over-pressuring (PgasTOT > Psat(H2O) at run T), is degassed (by single-step degassing) to separate a scrubbed gas phase. As an application of the model results, the model compositions of the separated gases are finally compared with compositions of natural gas emissions from Hekla volcano (T< 100°C) and from Krisuvik geothermal system (T> 100°C), resulting into an excellent agreement. The compositions of the model solutions are also in fair agreement with compositions of natural thermal water samples. We conclude that our EQ3/6-based reaction path simulations offer a realistic representation of gas-water-rock interaction processes occurring underneath active magmatic-hydrothermal systems

  8. Hydrothermal synthesis map of bismuth titanates

    SciTech Connect

    Sardar, Kripasindhu; Walton, Richard I.

    2012-05-15

    The hydrothermal synthesis of four bismuth titanate materials from common bismuth and titanium precursors under hydrothermal conditions is described. Reaction of NaBiO{sub 3}{center_dot}2H{sub 2}O and anatase TiO{sub 2} in concentrated NaOH solution at 240 Degree-Sign C is shown to produce perovskite and sillenite phases Na{sub 0.5}Bi{sub 0.5}TiO{sub 3} and Bi{sub 12}TiO{sub 20}, depending on the ratio of metal precursors used. When KOH solution is used and a 1:1 ratio of the same precursors, a pyrochlore Bi{sub 1.43}Ti{sub 2}O{sub 6}(OH){sub 0.29}(H{sub 2}O){sub 0.66} is formed. The use of a mixture of HNO{sub 3} and NaOH is shown to facilitate the formation of the Aurivillius-type bismuth titanate Bi{sub 4}Ti{sub 3}O{sub 12}. The phases have been isolated separately as phase-pure powders and profile refinement of powder X-ray diffraction data allows comparisons with comparable materials reported in the literature. Analysis of Bi L{sub III}-edge X-ray absorption near edge structure (XANES) spectra of the materials shows the oxidation state of bismuth is +3 in all of the hydrothermally derived products. - Graphical abstract: Use of NaBiO{sub 3}{center_dot}2H{sub 2}O and TiO{sub 2} as reagents under hydrothermal conditions allows the phase-pure preparation of four crystalline bismuth titanate materials. Highlights: Black-Right-Pointing-Pointer NaBiO{sub 3} and TiO{sub 2} under hydrothermal conditions allow formation of bismuth titanates. Black-Right-Pointing-Pointer Synthesis of four distint phases has been mapped. Black-Right-Pointing-Pointer Bi LIII-edge XANES shows Bi is reduced to oxidation state +3 in all materials. Black-Right-Pointing-Pointer A new hydrated bismuth titanate pyrochlore has been isolated.

  9. Hydrothermal calcium modification of 316L stainless steel and its apatite forming ability in simulated body fluid.

    PubMed

    Valanezahad, Alireza; Ishikawa, Kunio; Tsuru, Kanji; Maruta, Michito; Matsuya, Shigeki

    2011-01-01

    To understand the feasibility of calcium (Ca) modification of type 316L stainless steel (316L SS) surface using hydrothermal treatment, 316L SS plates were treated hydrothermally in calcium chloride (CaCl(2)) solution. X-ray photoelectron spectroscopic analysis revealed that the surface of 316L SS plate was modified with Ca after hydrothermal treatment at 200°C. And the immobilized Ca increased with CaCl(2) concentration. However no Ca-modification was occurred for 316L SS plates treated at 100°C. When Ca-modified 316L SS plate was immersed in simulated body fluid (SBF) with ion concentrations nearly equal to those of human blood plasma, low crystalline apatite was precipitated on its surface whereas no precipitate was observed on non Ca-modified 316L SS. The results obtained in the present study indicated that hydrothermal treatment at 200°C in CaCl(2) solution is useful for Ca-modification of 316L SS, and Ca-modification plays important role for apatite precipitation in SBF.

  10. Resistivity structure and geochemistry of the Jigokudani Valley hydrothermal system, Mt. Tateyama, Japan

    NASA Astrophysics Data System (ADS)

    Seki, Kaori; Kanda, Wataru; Tanbo, Toshiya; Ohba, Takeshi; Ogawa, Yasuo; Takakura, Shinichi; Nogami, Kenji; Ushioda, Masashi; Suzuki, Atsushi; Saito, Zenshiro; Matsunaga, Yasuo

    2016-10-01

    This study clarifies the hydrothermal system of Jigokudani Valley near Mt. Tateyama volcano in Japan by using a combination of audio-frequency magnetotelluric (AMT) survey and hot-spring water analysis in order to assess the potential of future phreatic eruptions in the area. Repeated phreatic eruptions in the area about 40,000 years ago produced the current valley morphology, which is now an active solfatara field dotted with hot springs and fumaroles indicative of a well-developed hydrothermal system. The three-dimensional (3D) resistivity structure of the hydrothermal system was modeled by using the results of an AMT survey conducted at 25 locations across the valley in 2013-2014. The model suggests the presence of a near-surface highly conductive layer of < 50 m in thickness across the entire valley, which is interpreted as a cap rock layer. Immediately below the cap rock is a relatively resistive body interpreted as a gas reservoir. Field measurements of temperature, pH, and electrical conductivity (EC) were taken at various hot springs across the valley, and 12 samples of hot-spring waters were analyzed for major ion chemistry and H2O isotopic ratios. All hot-spring waters had low pH and could be categorized into three types on the basis of the Cl-/SO 42 - concentration ratio, with all falling largely on a mixing line between magmatic fluids and local meteoric water (LMW). The geochemical analysis suggests that the hydrothermal system includes a two-phase zone of vapor-liquid. A comparison of the resistivity structure and the geochemically inferred structure suggests that a hydrothermal reservoir is present at a depth of approximately 500 m, from which hot-spring water differentiates into the three observed types. The two-phase zone appears to be located immediately beneath the cap rock structure. These findings suggest that the hydrothermal system of Jigokudani Valley exhibits a number of factors that could trigger a future phreatic eruption.

  11. Numerical Modeling of Multiphase Fluid Flow in Ore-Forming Hydrothermal Systems

    NASA Astrophysics Data System (ADS)

    Weis, P.; Driesner, T.; Coumou, D.; Heinrich, C. A.

    2007-12-01

    Two coexisting fluid phases - a variably saline liquid and a vapor phase - are ubiquitous in ore-forming and other hydrothermal systems. Understanding the dynamics of phase separation and the distinct physical and chemical evolution of the two fluids probably plays a key role in generating different ore deposit types, e.g. porphyry type, high and low sulfidation Cu-Mo-Au deposits. To this end, processes within hydrothermal systems have been studied with a refined numerical model describing fluid flow in transient porous media (CSP~5.0). The model is formulated on a mass, energy and momentum conserving finite-element-finite-volume (FEFV) scheme and is capable of simulating multiphase flow of NaCl-H20 fluids. Fluid properties are computed from an improved equation of state (SOWAT~2.0). It covers conditions with temperatures of up to 1000 degrees~C, pressures of up to 500 MPa, and fluid salinities of 0~to 100%~NaCl. In particular, the new set-up allows for a more accurate description of fluid phase separation during boiling of hydrothermal fluids into a vapor and a brine phase. The geometric flexibility of the FEFV-meshes allows for investigations of a large variety of geological settings, ranging from ore-forming processes in magmatic hydrothermal system to the dynamics of black smokers at mid-ocean ridges. Simulations demonstrated that hydrothermal convection patterns above cooling plutons are primarily controlled by the system-scale permeability structure. In porphyry systems, high fluid pressures develop in a stock rising from the magma chamber which can lead to rock failure and, eventually, an increase in permeability due to hydrofracturing. Comparisons of the thermal evolution as inferred from modeling studies with data from fluid inclusion studies of the Pb-Zn deposits of Madan, Bulgaria are in a strikingly good agreement. This indicates that cross-comparisons of field observations, analytical data and numerical simulations will become a powerful tool towards a

  12. Hydrothermal Conditions and the Origin of Cellular Life.

    PubMed

    Deamer, David W; Georgiou, Christos D

    2015-12-01

    The conditions and properties of hydrothermal vents and hydrothermal fields are compared in terms of their ability to support processes related to the origin of life. The two sites can be considered as alternative hypotheses, and from this comparison we propose a series of experimental tests to distinguish between them, focusing on those that involve concentration of solutes, self-assembly of membranous compartments, and synthesis of polymers. Key Word: Hydrothermal systems.

  13. Hydrothermal Conditions and the Origin of Cellular Life.

    PubMed

    Deamer, David W; Georgiou, Christos D

    2015-12-01

    The conditions and properties of hydrothermal vents and hydrothermal fields are compared in terms of their ability to support processes related to the origin of life. The two sites can be considered as alternative hypotheses, and from this comparison we propose a series of experimental tests to distinguish between them, focusing on those that involve concentration of solutes, self-assembly of membranous compartments, and synthesis of polymers. Key Word: Hydrothermal systems. PMID:26684507

  14. Interactions Between Serpentinization, Hydrothermal Activity and Microbial Community at the Lost City Hydrothermal Field

    NASA Astrophysics Data System (ADS)

    Delacour, A.; Frueh-Green, G. L.; Bernasconi, S. M.; Schaeffer, P.; Frank, M.; Gutjahr, M.; Kelley, D. S.

    2008-12-01

    Seafloor investigations of slow- and ultraslow-spreading ridges have reported many occurrences of exposed mantle peridotites and gabbroic rocks on the ocean floor. Along the Mid-Atlantic Ridge, these uplifted portions of oceanic crust host high-temperature black smoker-type hydrothermal systems (e.g., Rainbow, Logatchev, Saldanha), and the more distinct low-temperature Lost City Hydrothermal Field (LCHF). Built on a southern terrace of the Atlantis Massif, the LCHF is composed of carbonate-brucite chimneys that vent alkaline and low-temperature (40-90°C) hydrothermal fluids. These fluids are related to serpentinization of mantle peridotites, which together with minor gabbroic intrusions form the basement of the LCHF. Long-lived hydrothermal activity at Lost City led to extensive seawater-rock interaction in the basement rocks, as indicated by seawater-like Sr- and mantle to unradiogenic Nd-isotope compositions of the serpentinites. These high fluid fluxes in the southern part of the massif influenced the conditions of serpentinization and have obliterated the early chemical signatures in the serpentinites, especially those of carbon and sulfur. Compared to reducing conditions commonly formed during the first stages of serpentinization, serpentinization at Lost City is characterized by relatively oxidizing conditions resulting in a predominance of magnetite, the mobilization/dissolution and oxidation of igneous sulfides to secondary pyrite, and the incorporation of seawater sulfate, all leading to high bulk-rock S-isotope compositions. The Lost City hydrothermal fluids contain high concentrations in methane, hydrogen, and low-molecular weight hydrocarbons considered as being produced abiotically. In contrast, organic compounds in the serpentinites are dominated by the occurrences of isoprenoids (pristane, phytane, and squalane), polycyclic compounds (hopanes and steranes), and higher abundances of C16 to C20 n-alkanes indicative of a marine organic input. We

  15. The Trans-Atlantic Geotraverse hydrothermal field: A hydrothermal system on an active detachment fault

    NASA Astrophysics Data System (ADS)

    Humphris, Susan E.; Tivey, Margaret K.; Tivey, Maurice A.

    2015-11-01

    Over the last ten years, geophysical studies have revealed that the Trans-Atlantic Geotraverse (TAG) hydrothermal field (26°08‧N on the Mid-Atlantic Ridge) is located on the hanging wall of an active detachment fault. This is particularly important in light of the recognition that detachment faulting accounts for crustal accretion/extension along a significant portion of the Mid-Atlantic Ridge, and that the majority of confirmed vent sites on this slow-spreading ridge are hosted on detachment faults. The TAG hydrothermal field is one of the largest sites of high-temperature hydrothermal activity and mineralization found to date on the seafloor, and is comprised of active and relict deposits in different stages of evolution. The episodic nature of hydrothermal activity over the last 140 ka provides strong evidence that the complex shape and geological structure of the active detachment fault system exerts first order, but poorly understood, influences on the hydrothermal circulation patterns, fluid chemistry, and mineral deposition. While hydrothermal circulation extracts heat from a deep source region, the location of the source region at TAG is unknown. Hydrothermal upflow is likely focused along the relatively permeable detachment fault interface at depth, and then the high temperature fluids leave the low-angle portion of the detachment fault and rise vertically through the highly fissured hanging wall to the seafloor. The presence of abundant anhydrite in the cone on the summit of the TAG active mound and in veins in the crust beneath provides evidence for a fluid circulation system that entrains significant amounts of seawater into the shallow parts of the mound and stockwork. Given the importance of detachment faulting for crustal extension at slow spreading ridges, the fundamental question that still needs to be addressed is: How do detachment fault systems, and the structure at depth associated with these systems (e.g., presence of plutons and/or high

  16. Synthesis of Nanoparticles via Solvothermal and Hydrothermal Methods

    SciTech Connect

    Li, Jianlin; Wu, Qingliu; Wu, Ji

    2015-01-01

    This chapter summarizes the synthesis of various types of nanoparticles as well as surface modifications of nanomaterials using hydrothermal and solvothermal methods. First, the definition, history, instrumentation, and mechanism of hydrothermal and solvothermal methods as well as the important parameters af-fecting the nucleation and crystal growth of nanomaterials are briefly introduced. Then the specific hydrothermal and solvothermal methods used to grow oxides, Group II-VI, III-V, IV, transitional metals, and metal-organic framework nanoparticles are summarized. Finally, the hydrothermal and solvothermal strategies used for the surface modification of nanomaterials are discussed.

  17. The Magmatic-Hydrothermal Transition of The Taupo Volcanic Zone, New Zealand

    NASA Astrophysics Data System (ADS)

    Chambefort, I. S.; Dilles, J. H.; Heinrich, C. A.; Wälle, M.

    2015-12-01

    The Taupo Volcanic Zone (TVZ), New Zealand is a rifting arc that produced over the last 2 My over 6000 km3 of caldera-associated volcanic products. About four times as much magma is estimated to be trapped at depth below the central TVZ than is erupted, feeding heat, volatiles and chemicals into 23 geothermal systems with a total of ca. 4.2 GW thermal energy release. We present here a combined study linking melt, hypersaline and dilute fluid inclusion chemistry, surface and reservoir fluid chemistry and whole rock lithochemistry and discuss the magmatic-hydrothermal chemical zoning in large silicic systems. New dataset of full lithogeochemistry in active geothermal systems of the TVZ refine the zoned chemical footprint left by both dilute meteoric-dominated and magmatic-hydrothermal fluids. Altered whole rock trace elements content (including precious metals and volatiles) shows major variation with depth, due to the influence of past hydrothermal activity, magmatic degassing, natural variability of the reservoir rocks, and current active fluid-rock interactions. The concentrations of Li, Cs, Tl, Bi, Sn, Ag, Se, Te, as well as Au, generally increase upward toward the paleosurface, where they are 10-100 times greater than near known or potentially 'active' intrusions. New direct in-situ analyses of trapped fluid inclusions in phenocrysts and hydrothermal veins associated with magmatic subsolidus crystallization are compared with liquid-dominated dilute fluid inclusions and geothermal fluids Li, Cs, B, Na, Cl, K content (and precious metals) providing a unique direct assessment of the role of each component (magma, rock, fluids) in New Zealand's world known geothermal systems.

  18. Mineralogical and Fluid Inclusion Studies on Seafloor Hydrothermal Vents at TA25 Caldera, Tonga Arc

    NASA Astrophysics Data System (ADS)

    Choi, S. K.; Pak, S. J.; Choi, S. H.; Lee, K. Y.; Kim, H. S.; Lee, I. K.

    2015-12-01

    The extensive hydrothermal vent field was discovered at TA25("V18s-HR" in the SO-167 cruise) caldera in the Tonga arc, southwest Pacific. The TA25 caldera is a submarine volcano of dacitic composition and hosts the NE- and NW-trending hydrothermal vent on the western caldera wall. These active hydrothermal crusters are mostly small (chimney: <0.5m in tall; sulfide mound: <3m in diameter) and immature, and emit the transparent fluids of which temperature range from 150℃ to 242℃ (average = 203℃). The hydrothermal sulfide ores, recovered by ROV and/or TV-grab, are mainly composed of sphalerite, pyrite, marcasite, galena, chalcopyrite, covellite, tennantite, enargite and sulfates such as barite, gypsum/anhydrite. It is observed that three distinct mineralogical zonation from exterior to interior of the chimneys: (1) barite-gypsum/anhydrite-pyrite-sphalerite; (2) sphalerite-pyrite-galena±chalcopyrite; (3) sphaleirte-pyrite-chalcopyrite-enargite-tennantite±galena±covellite. FeS content in sphalerite increases from chimney exterior to interior. Chalcopyrite is more abundant in the mound than in the chimney, implying fluid temperatures in mound are greater than in the chimney. The enargite assemblage (pyrite-chalcopyrite-enargite-tennantite) is indicative of high-sulfidation epithermal deposits. Fluid inclusions on barite crystals from mound samples show mono-type inclusion (two-phase liquid-rich inclusions) which is less than 20㎛ in diameter. Homogenization temperatures and salinities from fluid inclusion study range from 148℃ to 341℃ (average = 213℃) and 0.4 to 3.6 equiv. wt.% NaCl, respectively. The main mineralization temperature in mound might be greater than 200℃ since barite on fluid inclusion is early stage mineral.

  19. Silica nanoparticles in E ring ice grains as an indicator for hydrothermal activities at Enceladus

    NASA Astrophysics Data System (ADS)

    Postberg, F.; Hsu, H. W.; Sekine, Y.

    2013-09-01

    Since 2004 the Cosmic Dust Analyser (CDA) on board the Cassini spacecraft detects nano-meter sized dust particles, so called stream particles, in the Saturnian system. Recently it has been shown that they are released from E ring ice grains in which they were previously embedded [1]. As a consequence the nanograins must have been generated at Saturns active moon Enceladus which feeds the E ring by its spectacular jets of vapour and ice grains. Liquid water below the moons icy crust is known to be the dominant source of these jets [2, 3]. New results from CDA presented here indicate that stream particles actually are nano-silica grains. The most prominent geological process which produces nano-phase silica are hydrothermal rock-water interactions. This process has recently been intensely studied for hydrothermal systems on Earth [e.g. 4, 5]. The measured concentration, composition and size range observed at in the Saturnian system precisely matches a hydrothermal synthesis origin. Thus, we propose nano-colloidal silica to be present at mMol concentrations in Enceladus' subsurface waters. We were able to reproduce the proposed hydrothermal serpentinisation processes in a geochemical long term experiment in the laboratory. As there are no alternative formation scenarios which are in agreement with the CDA observations our results indicate ongoing rock-water interactions inside Enceladus at temperatures clearly exceeding 100°C. We discuss implications for Enceladus geochemistry, like salinity, possible ranges of temperature and pH, as well as the mineral composition of the Enceladian rock core.

  20. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil.

    PubMed

    Zheng, Ji-Lu; Zhu, Ming-Qiang; Wu, Hai-tang

    2015-09-01

    It is imperative that swine carcasses are disposed of safely, practically and economically. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil was performed. Firstly, the effects of temperature, reaction time and pH value on the yield of each liquefaction product were determined. Secondly, liquefaction products, including bio-oil and solid residue, were characterized. Finally, the energy recovery ratio (ERR), which was defined as the energy of the resultant products compared to the energy input of the material, was investigated. Our experiment shows that reaction time had certain influence on the yield of liquefaction products, but temperature and pH value had bigger influence on the yield of liquefaction products. Yields of 62.2wt% bio-oil, having a high heating value of 32.35MJ/kg and a viscosity of 305cp, and 22wt% solid residue were realized at a liquefaction temperature of 250°C, a reaction time of 60min and a pH value of 9.0. The bio-oil contained up to hundreds of different chemical components that may be classified according to functional groups. Typical compound classes in the bio-oil were hydrocarbons, organic acids, esters, ketones and heterocyclics. The energy recovery ratio (ERR) reached 93.63%. The bio-oil is expected to contribute to fossil fuel replacement in stationary applications, including boilers and furnaces, and upgrading processes for the bio-oil may be used to obtain liquid transport fuels. PMID:26013692

  1. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil.

    PubMed

    Zheng, Ji-Lu; Zhu, Ming-Qiang; Wu, Hai-tang

    2015-09-01

    It is imperative that swine carcasses are disposed of safely, practically and economically. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil was performed. Firstly, the effects of temperature, reaction time and pH value on the yield of each liquefaction product were determined. Secondly, liquefaction products, including bio-oil and solid residue, were characterized. Finally, the energy recovery ratio (ERR), which was defined as the energy of the resultant products compared to the energy input of the material, was investigated. Our experiment shows that reaction time had certain influence on the yield of liquefaction products, but temperature and pH value had bigger influence on the yield of liquefaction products. Yields of 62.2wt% bio-oil, having a high heating value of 32.35MJ/kg and a viscosity of 305cp, and 22wt% solid residue were realized at a liquefaction temperature of 250°C, a reaction time of 60min and a pH value of 9.0. The bio-oil contained up to hundreds of different chemical components that may be classified according to functional groups. Typical compound classes in the bio-oil were hydrocarbons, organic acids, esters, ketones and heterocyclics. The energy recovery ratio (ERR) reached 93.63%. The bio-oil is expected to contribute to fossil fuel replacement in stationary applications, including boilers and furnaces, and upgrading processes for the bio-oil may be used to obtain liquid transport fuels.

  2. Compounds inhibiting the bioconversion of hydrothermally pretreated lignocellulose.

    PubMed

    Ko, Ja Kyong; Um, Youngsoon; Park, Yong-Cheol; Seo, Jin-Ho; Kim, Kyoung Heon

    2015-05-01

    Hydrothermal pretreatment using liquid hot water, steam explosion, or dilute acids enhances the enzymatic digestibility of cellulose by altering the chemical and/or physical structures of lignocellulosic biomass. However, compounds that inhibit both enzymes and microbial activity, including lignin-derived phenolics, soluble sugars, furan aldehydes, and weak acids, are also generated during pretreatment. Insoluble lignin, which predominantly remains within the pretreated solids, also acts as a significant inhibitor of cellulases during hydrolysis of cellulose. Exposed lignin, which is modified to be more recalcitrant to enzymes during pretreatment, adsorbs cellulase nonproductively and reduces the availability of active cellulase for hydrolysis of cellulose. Similarly, lignin-derived phenolics inhibit or deactivate cellulase and β-glucosidase via irreversible binding or precipitation. Meanwhile, the performance of fermenting microorganisms is negatively affected by phenolics, sugar degradation products, and weak acids. This review describes the current knowledge regarding the contributions of inhibitors present in whole pretreatment slurries to the enzymatic hydrolysis of cellulose and fermentation. Furthermore, we discuss various biological strategies to mitigate the effects of these inhibitors on enzymatic and microbial activity to improve the lignocellulose-to-biofuel process robustness. While the inhibitory effect of lignin on enzymes can be relieved through the use of lignin blockers and by genetically engineering the structure of lignin or of cellulase itself, soluble inhibitors, including phenolics, furan aldehydes, and weak acids, can be detoxified by microorganisms or laccase.

  3. Hydrothermal Syntheses of Colloidal Carbon Spheres from Cyclodextrins

    SciTech Connect

    Shin, Yongsoon; Wang, Li Q.; Bae, In-Tae; Arey, Bruce W.; Exarhos, Gregory J.

    2008-09-18

    Colloidal carbon spheres have been prepared from aqueous alpha-, beta-, and gamma-cyclodextrin (CD) solutions in closed systems under hydrothermal conditions at 160 oC. Both liquid and solid-state 13C NMR spectra taken for samples at different reaction times have been used to monitor the dehydration and carbonization pathways. CD slowly hydrolyzes to glucose and forms 5-hydroxymethyl furfural (HMF) followed by carbonization into colloidal carbon spheres. The isolated carbon spheres are 70-150 nm in diameter, exhibit a core-shell structure, and are comprised of a condensed core (C=C) peppered with resident chemical functionalities including carboxylate and hydroxyl groups. Evidence from 13C solid-state NMR and FT-IR spectra reveal that the evolving carbon spheres show a gradual increase in the amount of aromatic carbon as a function of reaction time and that the carbon spheres generated from gamma-CD contain significantly higher aromatic carbon than those derived from alpha- and beta-CD.

  4. Laser refrigeration of hydrothermal nanocrystals in physiological media

    PubMed Central

    Roder, Paden B.; Smith, Bennett E.; Zhou, Xuezhe; Crane, Matthew J.; Pauzauskie, Peter J.

    2015-01-01

    Coherent laser radiation has enabled many scientific and technological breakthroughs including Bose–Einstein condensates, ultrafast spectroscopy, superresolution optical microscopy, photothermal therapy, and long-distance telecommunications. However, it has remained a challenge to refrigerate liquid media (including physiological buffers) during laser illumination due to significant background solvent absorption and the rapid (∼ps) nonradiative vibrational relaxation of molecular electronic excited states. Here we demonstrate that single-beam laser trapping can be used to induce and quantify the local refrigeration of physiological media by >10 °C following the emission of photoluminescence from upconverting yttrium lithium fluoride (YLF) nanocrystals. A simple, low-cost hydrothermal approach is used to synthesize polycrystalline particles with sizes ranging from <200 nm to >1 μm. A tunable, near-infrared continuous-wave laser is used to optically trap individual YLF crystals with an irradiance on the order of 1 MW/cm2. Heat is transported out of the crystal lattice (across the solid–liquid interface) by anti-Stokes (blue-shifted) photons following upconversion of Yb3+ electronic excited states mediated by the absorption of optical phonons. Temperatures are quantified through analysis of the cold Brownian dynamics of individual nanocrystals in an inhomogeneous temperature field via forward light scattering in the back focal plane. The cold Brownian motion (CBM) analysis of individual YLF crystals indicates local cooling by >21 °C below ambient conditions in D2O, suggesting a range of potential future applications including single-molecule biophysics and integrated photonic, electronic, and microfluidic devices. PMID:26589813

  5. Quantitative analysis of the hydrothermal system in Lassen Volcanic National Park and Lassen Known Geothermal Resource Area

    USGS Publications Warehouse

    Sorey, M.L.; Ingebritsen, S.E.

    1984-01-01

    The conceptual model of the Lassen system is termed a liquid-dominated hydrothermal system with a parasitic vapor-dominated zone. The essential feature of this model is that steam and steam-heated discharge at relatively high elevations in Lassen Volcanic National Park (LVNP) and liquid discharge with high chloride concentrations at relatively low elevations outside LVNP are both fed by an upflow of high-enthalpy two-phase fluid within the Park. Liquid flows laterally away from the upflow area towards the areas of high-chloride discharge, and steam rises through a vapor-dominated zone to feed the steam and steam-heated features. Numerical simulations show that several conditions are necessary for the development of this type of system, including (1) large-scale topographic relief, (2) an initial period of convective heating within an upflow zone followed by some change in hydrologic or geologic conditions that initiates drainage of liquid from portions of the upflow zone, and (3) low permeability barriers that inhibit the movement of cold water into the vapor zone. Simulations of thermal fluid withdrawal south of LVNP, carried out in order to determine the effects of such withdrawal on portions of the hydrothermal system within the Park, showed decreases in pressure and liquid saturation beneath the vapor zone which result in a temporary increase and subsequent decrease in the rate of upflow of steam. (USGS)

  6. Hydrothermal Pretreatment of Date Palm (Phoenix dactylifera L.) Leaflets and Rachis to Enhance Enzymatic Digestibility and Bioethanol Potential

    PubMed Central

    Fang, Chuanji; Schmidt, Jens Ejbye; Cybulska, Iwona; Brudecki, Grzegorz P.; Frankær, Christian Grundahl; Thomsen, Mette Hedegaard

    2015-01-01

    Date palm residues are one of the most promising lignocellulosic biomass for bioethanol production in the Middle East. In this study, leaflets and rachis were subjected to hydrothermal pretreatment to overcome the recalcitrance of the biomass for enzymatic conversion. Evident morphological, structural, and chemical changes were observed by scanning electron microscopy, X-ray diffraction, and infrared spectroscopy after pretreatment. High glucan (>90% for both leaflets and rachis) and xylan (>75% for leaflets and >79% for rachis) recovery were achieved. Under the optimal condition of hydrothermal pretreatment (210°C/10 min) highly digestible (glucan convertibility, 100% to leaflets, 78% to rachis) and fermentable (ethanol yield, 96% to leaflets, 80% to rachis) solid fractions were obtained. Fermentability test of the liquid fractions proved that no considerable inhibitors to Saccharomyces cerevisiae were produced in hydrothermal pretreatment. Given the high sugar recovery, enzymatic digestibility, and ethanol yield, production of bioethanol by hydrothermal pretreatment could be a promising way of valorization of date palm residues in this region. PMID:26347878

  7. Hydrothermal processes at Mount Rainier, Washington

    SciTech Connect

    Frank, D.G.

    1985-01-01

    Field studies and thermal-infrared mapping at Mount Rainier indicate areas of active hydrothermal alteration where excess surface heat flux is about 9 megawatts. Three representative settings include: (1) An extensive area (greater than 12,000 m/sup 2/) of heated ground and slightly acidic boiling-point fumaroles at 76-82/sup 0/C at East and West Craters on the volcano's summit; (2) A small area (less than 500 m/sup 2/) of heated ground and sub-boiling-point fumaroles at 55-60/sup 0/C on the upper flank at Disappointment Cleaver, and other probably similar areas at Willis Wall, Sunset Amphitheater, and the South Tahoma and Kautz headwalls; (3) Sulfate and carbon dioxide enriched thermal springs at 9-24/sup 0/C on the lower flank of the volcano in valley walls beside the Winthrop and Paradise Glaciers. In addition, chloride- and carbon dioxide-enriched thermal springs issue from thin sediments that overlie Tertiary rocks at, or somewhat beyond, the base of the volcanic edifice in valley bottoms of the Nisqually and Ohanapecosh Rivers where maximum spring temperatures are 19-25/sup 0/C, respectively, and where extensive travertine deposits have developed. The heat flow, distribution of thermal activity, and nature of alteration products indicate that a narrow, central hydrothermal system exists within Mount Rainier forming steam-heated snowmelt at the summit craters and localized leakage of steam-heated fluids within 2 kilometers of the summit. The lateral extent of the hydrothermal system is limited in that only sparse, neutral sulfate-enriched thermal water issues from the lower flank of the cone. Simulations of geochemical mass transfer suggest that the thermal springs may be derived from an acid sulfate-chloride parent fluid which has been neutralized by reaction with andesite and highly diluted with shallow ground water.

  8. The hydrothermal alteration of cooling lava domes

    NASA Astrophysics Data System (ADS)

    Ball, Jessica L.; Stauffer, Philip H.; Calder, Eliza S.; Valentine, Greg A.

    2015-12-01

    Hydrothermal alteration is a recognized cause of volcanic instability and edifice collapse, including that of lava domes or dome complexes. Alteration by percolating fluids transforms primary minerals in dome lavas to weaker secondary products such as clay minerals; moreover, secondary mineral precipitation can affect the porosity and permeability of dome lithologies. The location and intensity of alteration in a dome depend heavily on fluid pathways and availability in conjunction with heat supply. Here we investigate postemplacement lava dome weakening by hydrothermal alteration using a finite element numerical model of water migration in simplified dome geometries. This is combined with the rock alteration index (RAI) to predict zones of alteration and secondary mineral precipitation. Our results show that alteration potential is highest at the interface between the hot core of a lava dome and its clastic talus carapace. The longest lived alteration potential fields occur in domes with persistent heat sources and permeabilities that allow sufficient infiltration of water for alteration processes, but not so much that domes cool quickly. This leads us to conclude that alteration-induced collapses are most likely to be shallow seated and originate in the talus or talus/core interface in domes which have a sustained supply of magmatic heat. Mineral precipitation at these zones of permeability contrast could create barriers to fluid flow, potentially causing gas pressurization which might promote deeper seated and larger volume collapses. This study contributes to our knowledge of how hydrothermal alteration can affect lava domes and provides constraints on potential sites for alteration-related collapses, which can be used to target hazard monitoring.

  9. Mixing from below in hydrothermal ore deposits

    NASA Astrophysics Data System (ADS)

    Bons, Paul D.; Gomez-Rivas, Enrique; Markl, Gregor; Walter, Bejamin

    2014-05-01

    Unconformity-related hydrothermal ore deposits typically show indications of mixing of two end-member fluids: (a) hot, deep, rock-buffered basement brines and (b) colder fluids derived from the surface or overlying sediments. The hydromechanics of bringing these fluids together from above and below remain unclear. Classical percolative Darcy-flow models are inconsistent with (1) fluid overpressure indicated by fracturing and brecciation, (2) fast fluid flow indicated by thermal disequilibrium, and (3) strong fluid composition variations on the mm-scale, indicated by fluid inclusion analyses (Bons et al. 2012; Fusswinkel et al. 2013). We propose that fluids first descend, sucked down by desiccation reactions in exhumed basement. Oldest fluids reach greatest depths, where long residence times and elevated temperatures allow them the extensively equilibrate with their host rock, reach high salinity and scavenge metals, if present. Youngest fluids can only penetrate to shallower depths and can (partially) retain signatures from their origin, for example high Cl/Br ratios from the dissolution of evaporitic halite horizons. When fluids are released from all levels of the crustal column, these fluids mix during rapid ascent to form hydrothermal ore deposits. Mixing from below provides a viable hydromechanical mechanism to explain the common phenomenon of mixed shallow and deep fluids in hydrothermal ore deposits. Bons, P.D., Elburg, M.A., Gomez-Rivas, E. 2012. A review of the formation of tectonic veins and their microstructures. J. Struct. Geol. doi:10.1016/j.jsg.2012.07.005 Fusswinkel, T., Wagner, T., Wälle, M., Wenzel, T., Heinrich, C.A., Markl, M. 2013. Fluid mixing forms basement-hosted Pb-Zn deposits: Insight from metal and halogen geochemistry of individual fluid inclusions. Geology. doi:10.1130/G34092.1

  10. Hydrothermal synthesis of lutetium disilicate nanoparticles

    SciTech Connect

    Tang Xiaoping; Gao Yanfeng; Chen Hongfei; Luo Hongjie

    2012-04-15

    A simple, low-cost hydrothermal method was developed to synthesize irregular-and rod-shaped lutetium disilicate (Lu{sub 2}Si{sub 2}O{sub 7}) powders with sizes ranging from 71 to 340 nm. The synthesis temperature was 260 Degree-Sign C, which is nearly 1300 Degree-Sign C lower than that required for the solid-state reaction. The results indicated that both the hydrothermal temperature and pH values had great influences on the composition, crystalline phase and morphology of the powders. The formation mechanism, basic thermophysical properties, stability and anticorrosion properties of the Lu{sub 2}Si{sub 2}O{sub 7} powders were also investigated. The obtained powders possessed low thermal conductivity, a suitable thermal expansion coefficient (3.92-5.17 Multiplication-Sign 10{sup -6} K{sup -1}) with the silicon-based substrate and excellent thermal and structural stability. During hot corrosion testing, the surfaces of the samples appeared to react with the water and molten salt vapors, but no serious failure occurred. - Graphical abstract: An image for the as-prepared Lu{sub 2}Si{sub 2}O{sub 7} powders (left) and XRD pattern (right) (inset shows the SEM graph of powders). Highlights: Black-Right-Pointing-Pointer We synthesized Lu{sub 2}Si{sub 2}O{sub 7} powders via a hydrothermal process at 260 Degree-Sign C. Black-Right-Pointing-Pointer Crystalline phase and morphology of the powders changed with experimental parameter. Black-Right-Pointing-Pointer Hot corrosion was determined in an airflow environment containing alkaline vapor.

  11. Hydrothermal Liquefaction Treatment Preliminary Hazard Analysis Report

    SciTech Connect

    Lowry, Peter P.; Wagner, Katie A.

    2015-08-31

    A preliminary hazard assessment was completed during February 2015 to evaluate the conceptual design of the modular hydrothermal liquefaction treatment system. The hazard assessment was performed in 2 stages. An initial assessment utilizing Hazard Identification and Preliminary Hazards Analysis (PHA) techniques identified areas with significant or unique hazards (process safety-related hazards) that fall outside of the normal operating envelope of PNNL and warranted additional analysis. The subsequent assessment was based on a qualitative What-If analysis. This analysis was augmented, as necessary, by additional quantitative analysis for scenarios involving a release of hazardous material or energy with the potential for affecting the public.

  12. Vertical Cable Seismic Survey for Hydrothermal Deposit

    NASA Astrophysics Data System (ADS)

    Asakawa, E.; Murakami, F.; Sekino, Y.; Okamoto, T.; Ishikawa, K.; Tsukahara, H.; Shimura, T.

    2012-04-01

    The vertical cable seismic is one of the reflection seismic methods. It uses hydrophone arrays vertically moored from the seafloor to record acoustic waves generated by surface, deep-towed or ocean bottom sources. Analyzing the reflections from the sub-seabed, we could look into the subsurface structure. This type of survey is generally called VCS (Vertical Cable Seismic). Because VCS is an efficient high-resolution 3D seismic survey method for a spatially-bounded area, we proposed the method for the hydrothermal deposit survey tool development program that the Ministry of Education, Culture, Sports, Science and Technology (MEXT) started in 2009. We are now developing a VCS system, including not only data acquisition hardware but data processing and analysis technique. Our first experiment of VCS surveys has been carried out in Lake Biwa, JAPAN in November 2009 for a feasibility study. Prestack depth migration is applied to the 3D VCS data to obtain a high quality 3D depth volume. Based on the results from the feasibility study, we have developed two autonomous recording VCS systems. After we carried out a trial experiment in the actual ocean at a water depth of about 400m and we carried out the second VCS survey at Iheya Knoll with a deep-towed source. In this survey, we could establish the procedures for the deployment/recovery of the system and could examine the locations and the fluctuations of the vertical cables at a water depth of around 1000m. The acquired VCS data clearly shows the reflections from the sub-seafloor. Through the experiment, we could confirm that our VCS system works well even in the severe circumstances around the locations of seafloor hydrothermal deposits. We have, however, also confirmed that the uncertainty in the locations of the source and of the hydrophones could lower the quality of subsurface image. It is, therefore, strongly necessary to develop a total survey system that assures a accurate positioning and a deployment techniques

  13. Hydrothermal mineralising systems as critical systems

    NASA Astrophysics Data System (ADS)

    Hobbs, Bruce

    2015-04-01

    Hydrothermal mineralising systems as critical systems. Bruce E Hobbs1,2, Alison Ord1 and Mark A. Munro1. 1. Centre for Exploration Targeting, The University of Western Australia, M006, 35 Stirling Highway, Crawley, WA 6009, Australia. 2. CSIRO Earth and Resource Engineering, Bentley, WA, Australia Hydrothermal mineralising systems are presented as large, open chemical reactors held far from equilibrium during their life-time by the influx of heat, fluid and dissolved chemical species. As such they are nonlinear dynamical systems and need to be analysed using the tools that have been developed for such systems. Hydrothermal systems undergo a number of transitions during their evolution and this paper focuses on methods for characterising these transitions in a quantitative manner and establishing whether they resemble first or second (critical) phase transitions or whether they have some other kind of nature. Critical phase transitions are characterised by long range correlations for some parameter characteristic of the system, power-law probability distributions so that there is no characteristic length scale and a high sensitivity to perturbations; as one approaches criticality, characteristic parameters for the system scale in a power law manner with distance from the critical point. The transitions undergone in mineralised hydrothermal systems are: (i) widespread, non-localised mineral alteration involving exothermic mineral reactions that produce hydrous silicate phases, carbonates and iron-oxides, (ii) strongly localised veining, brecciation and/or stock-work formation, (iii) a series of endothermic mineral reactions involving the formation of non-hydrous silicates, sulphides and metals such as gold, (iv) multiple repetitions of transitions (ii) and (iii). We have quantified aspects of these transitions in gold deposits from the Yilgarn craton of Western Australia using wavelet transforms. This technique is convenient and fast. It enables one to establish if

  14. The Hydrothermal Circulation of the Atmosphere

    NASA Astrophysics Data System (ADS)

    Kjellsson, J.; Doos, K.; Laliberté, F. B.; Zika, J. D.

    2012-12-01

    The atmospheric circulation maintains the energy balance between the warm/moist regions and the colder/drier regions of the Earth. A well-studied aspect of the atmospheric circulation is the time-averaged zonal-mean meridional overturning circulation. The meridional overturning describes the Hadley, Ferrel and Polar Cells in each hemisphere. However, in isobaric coordinates, the zonal average is unable to capture zonally asymmetric features such as the Walker circulation and transient exchanges of heat and moisture. The Walker Circulation is restricted to equatorial regions, and is commonly studied using a meridional mean over a limited region with ill-defined latitudinal boundaries. The Walker Circulation is thus neither mass-conserving nor uniquely defined. To overtcome these limitations, the Walker circulation is often diagnosed using vertical velocity. As a consequence, it is difficult to distinguish between the zonal-mean circulation (Hadley Circulation) and the zonal asymmetries (Walker Circulation). Global mass and energy transport is here investigated using a moisture-heat perspective. A hydrothermal streamfunction is defined where latent heat and dry static energy act as coordinates. Because the hydrothermal streamfunction resides in purely thermodynamical space, it does not differentiate between zonal, meridional, or vertical transports. The hydrothermal streamfunction shows the global overturning circulation as a unified cycle. It describes a cycle with three branches: i) a convective branch where latent heat is converted into sensible heat along moist adiabats, ii) a cooling branch where dry air loses energy due to radiative damping and iii) a return branch where cold, dry air is heated and moistened following the Clausius-Clapeyron relationship. These three branches form a single cell of more than 400 Sv with at least 100 Sv due to zonal motions such as the Walker Circulation. The cell is also found fairly stationary on seasonal and inter

  15. Liquid rocket engine injectors

    NASA Technical Reports Server (NTRS)

    Gill, G. S.; Nurick, W. H.

    1976-01-01

    The injector in a liquid rocket engine atomizes and mixes the fuel with the oxidizer to produce efficient and stable combustion that will provide the required thrust without endangering hardware durability. Injectors usually take the form of a perforated disk at the head of the rocket engine combustion chamber, and have varied from a few inches to more than a yard in diameter. This monograph treats specifically bipropellant injectors, emphasis being placed on the liquid/liquid and liquid/gas injectors that have been developed for and used in flight-proven engines. The information provided has limited application to monopropellant injectors and gas/gas propellant systems. Critical problems that may arise during injector development and the approaches that lead to successful design are discussed.

  16. Production of monosaccharides from napier grass by hydrothermal process with phosphoric acid.

    PubMed

    Takata, Eri; Tsutsumi, Ken; Tsutsumi, Yuji; Tabata, Kenji

    2013-09-01

    The production of monosaccharides from napier grass was investigated in the presence of acid catalysts using the hydrothermal process. When the napier grass was treated with 3 wt.% phosphoric acid at 160°C for 15min, the xylose yield reached 10.3 wt.%, corresponding to 72.0% of the xylan in it, whereas glucose was hardly obtained. A combined process was then conducted using an 85 wt.% phosphoric acid treatment at 60 °C for 1h followed by a hydrothermal treatment with 3 wt.% phosphoric acid. In the initial treatment with concentrated phosphoric acid the most of xylan was hydrolyzed to xylose, and the crystalline cellulose was converted to its amorphous form. The hydrolysis of cellulose to glucose was significantly enhanced during the following hydrothermal process with 3 wt.% phosphoric acid at 200 °C for 8 min. Consequently, 77.2% yield of xylose and 50.0% yield of glucose were obtained from the combined process.

  17. Hydrothermal synthesis of highly nitrogen-doped few-layer graphene via solid–gas reaction

    SciTech Connect

    Liang, Xianqing; Zhong, Jun; Shi, Yalin; Guo, Jin; Huang, Guolong; Hong, Caihao; Zhao, Yidong

    2015-01-15

    Highlights: • A novel approach to synthesis of N-doped few-layer graphene has been developed. • The high doping levels of N in products are achieved. • XPS and XANES results reveal a thermal transformation of N bonding configurations. • The developed method is cost-effective and eco-friendly. - Abstract: Nitrogen-doped (N-doped) graphene sheets with high doping concentration were facilely synthesized through solid–gas reaction of graphene oxide (GO) with ammonia vapor in a self-designed hydrothermal system. The morphology, surface chemistry and electronic structure of N-doped graphene sheets were investigated by TEM, AFM, XRD, XPS, XANES and Raman characterizations. Upon hydrothermal treatment, up to 13.22 at% of nitrogen could be introduced into the crumpled few-layer graphene sheets. Both XPS and XANES analysis reveal that the reaction between oxygen functional groups in GO and ammonia vapor produces amide and amine species in hydrothermally treated GO (HTGO). Subsequent thermal annealing of the resultant HTGO introduces a gradual transformation of nitrogen bonding configurations in graphene sheets from amine N to pyridinic and graphitic N with the increase of annealing temperature. This study provides a simple but cost-effective and eco-friendly method to prepare N-doped graphene materials in large-scale for potential applications.

  18. Hydrothermal alteration in oceanic ridge volcanics: A detailed study at the Galapagos Fossil Hydrothermal Field

    USGS Publications Warehouse

    Ridley, W.I.; Perfit, M.R.; Josnasson, I.R.; Smith, M.F.

    1994-01-01

    The Galapagos Fossil Hydrothermal Field is composed of altered oceanic crust and extinct hydrothermal vents within the eastern Galapagos Rift between 85??49???W and 85??55???W. The discharge zone of the hydrothermal system is revealed along scarps, thus providing an opportunity to examine the uppermost mineralized, and highly altered interior parts of the crust. Altered rocks collected in situ by the submersible ALVIN show complex concentric alteration zones. Microsamples of individual zones have been analysed for major/minor, trace elements, and strontium isotopes in order to describe the complex compositional details of the hydrothermal alteration. Interlayered chlorite-smectite and chlorite with disequilibrium compositions dominate the secondary mineralogy as replacement phases of primary glass and acicular pyroxene. Phenocrysts and matrix grains of plagioclase are unaffected during alteration. Using a modification of the Gresens' equation we demonstrate that the trivalent rare earth elements (REEs) are relatively immobile, and calculate degrees of enrichment and depletion in other elements. Strontium isotopic ratios increase as Sr concentrations decrease from least-altered cores to most-altered rims and cross-cutting veins in individual samples, and can be modeled by open system behaviour under low fluid-rock ratio (< 10) conditions following a period of lower-temperature weathering of volcanics within the rift zone. The complex patterns of element enrichment and depletion and strontium isotope variations indicate mixing between pristine seawater and ascending hot fluids to produce a compositional spectrum of fluids. The precipitation of base-metal sulfides beneath the seafloor is probably a result of fluid mixing and cooling. If, as suggested here, the discharge zone alteration occurred under relatively low fluid-rock ratios, then this shallow region must play an important role in determining the exit composition of vent fluids in marine hydrothermal systems

  19. Geology and hydrothermal evolution of the Mothra Hydrothermal Field, Endeavour Segment, Juan de Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Glickson, Deborah A.; Kelley, Deborah S.; Delaney, John R.

    2007-06-01

    Detailed characterization of the Mothra Hydrothermal Field, the most southern and spatially extensive field on the Endeavour Segment of the Juan de Fuca Ridge, provides new insights into its geologic and hydrothermal development. Meter-scale bathymetry, side-scan sonar imagery, and direct dive observations show that Mothra is composed of six actively venting sulfide clusters spaced 40-200 m apart. Chimneys within each cluster have similar morphology and venting characteristics, and all clusters host a combination of active and extinct sulfide structures. Black smoker chimneys venting fluids above 300°C are rare, while more common lower-temperature, diffusely venting chimneys support dense colonies of macrofauna and bacterial mat. Hydrothermal sediment and extinct sulfide debris cover 10-15 m of the seafloor surrounding each vent cluster, obscuring the underlying basaltic substrate of light to moderately sedimented pillow, lobate, sheet, and chaotic flows, basalt talus, and collapse terrain. Extinct sulfide chimneys and debris between the clusters indicate that hydrothermal flow was once more widespread and that it has shifted spatially over time. The most prominent structural features in the axial valley at Mothra are regional (020°) trending faults and fissures and north-south trending collapse basins. The location of actively venting clusters within the field is controlled by (1) localization of fluid upflow along the western boundary fault zone, and diversion of these fluids by antithetic faults to feed vent clusters near the western valley wall, and (2) tapping of residual magmatic heat in the central part of the axial valley, which drives flow beneath vent clusters directly adjacent to the collapse basins 70-90 m east of the western valley wall. These processes form the basis for a model of axial valley and hydrothermal system development at Mothra, in which the field is initiated by an eruptive-diking episode and sustained through intense microseismicity

  20. Hydrothermal alteration in oceanic ridge volcanics: A detailed study at the Galapagos Fossil Hydrothermal Field

    SciTech Connect

    Ridley, W.I.; Perfit, M.R.; Smith, M.F.; Jonasson, I.R.

    1994-06-01

    The Galapagos Fossil Hydrothermal Field is composed of altered oceanic crust and extinct hydrothermal vents within the eastern Galapagos Rift between 85{degree}49 feet W and 85{degree} 55 feet W. The discharge zone of the hydrothermal system is revealed along scarps, thus providing an opportunity to examine the uppermost mineralized, and highly altered interior parts of the crust. Altered rocks collected in situ by the submersible ALVIN show complex concentric alteration zones. Microsamples of individual zones have been analysed for major/minor, trace elements, and strontium isotopes in order to describe the complex compositional details of the hydrothermal alteration. Interlayered chlorite-smectite and chlorite with disequilibrium compositions dominate the secondary mineralogy as replacement phases of primary glass and acicular pyroxene. Phenocrysts and matrix grains of plagioclase are unaffected during alteration. Using a modification of the Gresens` equation we demonstrate that the trivalent rare earth elements (REEs) are relatively immobile, and calculate degrees of enrichment and depletion in other elements. Strontium isotopic ratios increase as Sr concentrations decrease from least-altered cores to most-altered rims and cross-cutting veins in individual samples, and can be modeled by open system behaviour under low fluid-rock ratio (<10) conditions following a period of lower-temperature weathering of volcanics within the rift zone. The complex patterns of element enrichment and depletion and strontium isotope variations indicate mixing between pristine seawater and ascending hot fluids to produce a compositional spectrum of fluids. If, as suggested here, the discharge zone alteration occurred under relatively low fluid-rock ratios, then this shallow region must play an important role in determining the exit composition of vent fluids in marine hydrothermal systems. 50 refs., 10 figs., 4 tabs.

  1. Carbon dioxide in magmas and implications for hydrothermal systems

    USGS Publications Warehouse

    Lowenstern, J. B.

    2001-01-01

    This review focuses on the solubility, origin, abundance, and degassing of carbon dioxide (CO2) in magma-hydrothermal systems, with applications for those workers interested in intrusion-related deposits of gold and other metals. The solubility of CO2 increases with pressure and magma alkalinity. Its solubility is low relative to that of H2O, so that fluids exsolved deep in the crust tend to have high CO2/H2O compared with fluids evolved closer to the surface. Similarly, CO2/H2O will typically decrease during progressive decompression- or crystallization-induced degassing. The temperature dependence of solubility is a function of the speciation of CO2, which dissolves in molecular form in rhyolites (retrograde temperature solubility), but exists as dissolved carbonate groups in basalts (prograde). Magnesite and dolomite are stable under a relatively wide range of mantle conditions, but melt just above the solidus, thereby contributing CO2 to mantle magmas. Graphite, diamond, and a free CO2-bearing fluid may be the primary carbon-bearing phases in other mantle source regions. Growing evidence suggests that most CO2 is contributed to arc magmas via recycling of subducted oceanic crust and its overlying sediment blanket. Additional carbon can be added to magmas during magma-wallrock interactions in the crust. Studies of fluid and melt inclusions from intrusive and extrusive igneous rocks yield ample evidence that many magmas are vapor saturated as deep as the mid crust (10-15 km) and that CO2 is an appreciable part of the exsolved vapor. Such is the case in both basaltic and some silicic magmas. Under most conditions, the presence of a CO2-bearing vapor does not hinder, and in fact may promote, the ascent and eruption of the host magma. Carbonic fluids are poorly miscible with aqueous fluids, particularly at high temperature and low pressure, so that the presence of CO2 can induce immiscibility both within the magmatic volatile phase and in hydrothermal systems

  2. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil

    SciTech Connect

    Zheng, Ji-Lu Zhu, Ming-Qiang; Wu, Hai-tang

    2015-09-15

    Highlights: • Swine carcasses can be converted to bio-oil by alkaline hydrothermal liquefaction. • It seems that the use of the bio-oil for heat or CHP is technically suitable. • Some valuable chemicals were found in the bio-oils. • The bio-oil and the solid residue constituted an energy efficiency of 93.63% for the feedstock. • The solid residue can be used as a soil amendment, to sequester C and for preparing activated carbon. - Abstract: It is imperative that swine carcasses are disposed of safely, practically and economically. Alkaline hydrothermal liquefaction of swine carcasses to bio-oil was performed. Firstly, the effects of temperature, reaction time and pH value on the yield of each liquefaction product were determined. Secondly, liquefaction products, including bio-oil and solid residue, were characterized. Finally, the energy recovery ratio (ERR), which was defined as the energy of the resultant products compared to the energy input of the material, was investigated. Our experiment shows that reaction time had certain influence on the yield of liquefaction products, but temperature and pH value had bigger influence on the yield of liquefaction products. Yields of 62.2 wt% bio-oil, having a high heating value of 32.35 MJ/kg and a viscosity of 305cp, and 22 wt% solid residue were realized at a liquefaction temperature of 250 °C, a reaction time of 60 min and a pH value of 9.0. The bio-oil contained up to hundreds of different chemical components that may be classified according to functional groups. Typical compound classes in the bio-oil were hydrocarbons, organic acids, esters, ketones and heterocyclics. The energy recovery ratio (ERR) reached 93.63%. The bio-oil is expected to contribute to fossil fuel replacement in stationary applications, including boilers and furnaces, and upgrading processes for the bio-oil may be used to obtain liquid transport fuels.

  3. The long term observed effect of air and water injection into a fracture hydrothermal system

    SciTech Connect

    Mario Cesar Suarez Arriaga; Mirna Tello Lopez; Luis de Rio; Hector Gutierrez Puente

    1992-01-01

    Injection of atmospheric air mixed with waste reinjection liquid, has been occurring since 1982 at the Los Azufres, Mexico volcanic hydrothermal system. Several chemical and thermodynamical evidences show that air injection into this fractured geothermal field, could be considered as a long term natural tracer test. Nitrogen and Argon separated from the air mixture migrate from reinjection wells to production zones following preferential paths closely related to high permeability conduits. These paths can be detected, looking into the N2 solubility evolution of production wells. The anisotropic nature of the fractured volcanic rock, would demand considerably amounts of artificial tracer in order to be detected at the producing wells, specially when fluid extraction is low. This explains the unsuccessful recovery of the artificial tracer tests performed in past years at Tejamaniles, the southern field's sector. On the other hand, chloride concentrations and other salts, are increasing in the liquid produced by the oldest wells of the sector.

  4. In vitro evaluation of H2O2 hydrothermal treatment of aged titanium surface to enhance biofunctional activity.

    PubMed

    Yoneyama, Yuya; Matsuno, Tomonori; Hashimoto, Yoshiya; Satoh, Tazuko

    2013-01-01

    Surface modification of titanium has been extensively investigated in implant science and technology in an effort to improve its osteoconductivity. The rate of protein adsorption on titanium surfaces is known to vary depending on the chemistry, structure, morphology, and titanium-specific biological aging of the surface. It is thus desirable to modify smooth titanium surfaces of miniimplants used as orthodontic anchors immediately prior to use. In this study, we have developed a simple surface modification of titanium alloy that improves its biofunctional activity. The surface of a Ti-6Al-4V disk was modified by applying 3% H(2)O(2) hydrothermal treatment using an autoclave. A nanostructured porous network TiO(2) was observed on the treated surface. Treated surfaces exhibited higher hydrophilicity, protein adsorption, and cell proliferation than untreated surfaces. 3% H(2)O(2) hydrothermal treatment is thought to provide biofunctional activity for aged titanium surface.

  5. Assessing the environmental impact of energy production from hydrochar generated via hydrothermal carbonization of food wastes.

    PubMed

    Berge, Nicole D; Li, Liang; Flora, Joseph R V; Ro, Kyoung S

    2015-09-01

    Although there are numerous studies suggesting hydrothermal carbonization is an environmentally advantageous process for transformation of wastes to value-added products, a systems level evaluation of the environmental impacts associated with hydrothermal carbonization and subsequent hydrochar combustion has not been conducted. The specific objectives of this work are to use a life cycle assessment approach to evaluate the environmental impacts associated with the HTC of food wastes and the subsequent combustion of the generated solid product (hydrochar) for energy production, and to understand how parameters and/or components associated with food waste carbonization and subsequent hydrochar combustion influence system environmental impact. Results from this analysis indicate that HTC process water emissions and hydrochar combustion most significantly influence system environmental impact, with a net negative GWP impact resulting for all evaluated substituted energy-sources except biomass. These results illustrate the importance of electricity production from hydrochar particularly when it is used to offset coal-based energy sources. HTC process water emissions result in a net impact to the environment, indicating a need for developing appropriate management strategies. Results from this analysis also highlight a need for additional exploration of liquid and gas-phase composition, a better understanding of how changes in carbonization conditions (e.g., reaction time and temperature) influence metal and nutrient fate, and the exploration of liquid-phase treatment. PMID:26049203

  6. Assessing the environmental impact of energy production from hydrochar generated via hydrothermal carbonization of food wastes.

    PubMed

    Berge, Nicole D; Li, Liang; Flora, Joseph R V; Ro, Kyoung S

    2015-09-01

    Although there are numerous studies suggesting hydrothermal carbonization is an environmentally advantageous process for transformation of wastes to value-added products, a systems level evaluation of the environmental impacts associated with hydrothermal carbonization and subsequent hydrochar combustion has not been conducted. The specific objectives of this work are to use a life cycle assessment approach to evaluate the environmental impacts associated with the HTC of food wastes and the subsequent combustion of the generated solid product (hydrochar) for energy production, and to understand how parameters and/or components associated with food waste carbonization and subsequent hydrochar combustion influence system environmental impact. Results from this analysis indicate that HTC process water emissions and hydrochar combustion most significantly influence system environmental impact, with a net negative GWP impact resulting for all evaluated substituted energy-sources except biomass. These results illustrate the importance of electricity production from hydrochar particularly when it is used to offset coal-based energy sources. HTC process water emissions result in a net impact to the environment, indicating a need for developing appropriate management strategies. Results from this analysis also highlight a need for additional exploration of liquid and gas-phase composition, a better understanding of how changes in carbonization conditions (e.g., reaction time and temperature) influence metal and nutrient fate, and the exploration of liquid-phase treatment.

  7. Influence of Hydrothermal Treatment on Physicochemical Properties and Drug Release of Anti-Inflammatory Drugs of Intercalated Layered Double Hydroxide Nanoparticles

    PubMed Central

    Gu, Zi; Wu, Aihua; Li, Li; Xu, Zhi Ping

    2014-01-01

    The synthesis method of layered double hydroxides (LDHs) determines nanoparticles’ performance in biomedical applications. In this study, hydrothermal treatment as an important synthesis technique has been examined for its influence on the physicochemical properties and the drug release rate from drug-containing LDHs. We synthesised MgAl–LDHs intercalated with non-steroidal anti-inflammatory drugs (i.e., naproxen, diclofenac and ibuprofen) using a co-precipitation method with or without hydrothermal treatment (150 °C, 4 h). After being hydrothermally treated, LDH–drug crystallites increased in particle size and crystallinity, but did not change in the interlayer anion orientation, gallery height and chemical composition. The drug release patterns of all studied LDH–drug hybrids were biphasic and sustained. LDHs loaded with diclofenac had a quicker drug release rate compared with those with naproxen and ibuprofen, and the drug release from the hydrothermally-treated LDH–drug was slower than the freshly precipitated LDH–drug. These results suggest that the drug release of LDH–drugs is influenced by the crystallite size of LDHs, which can be controlled by hydrothermal treatment, as well as by the drug molecular physicochemical properties. PMID:24858732

  8. Predicting the drying properties of sludge based on hydrothermal treatment under subcritical conditions.

    PubMed

    Mäkelä, Mikko; Fraikin, Laurent; Léonard, Angélique; Benavente, Verónica; Fullana, Andrés

    2016-03-15

    The effects of hydrothermal treatment on the drying properties of sludge were determined. Sludge was hydrothermally treated at 180-260 °C for 0.5-5 h using NaOH and HCl as additives to influence reaction conditions. Untreated sludge and attained hydrochar samples were then dried under identical conditions with a laboratory microdryer and an X-ray microtomograph was used to follow changes in sample dimensions. The effective moisture diffusivities of sludge and hydrochar samples were determined and the effect of process conditions on respective mean diffusivities evaluated using multiple linear regression. Based on the results the drying time of untreated sludge decreased from approximately 80 min to 37-59 min for sludge hydrochar. Drying of untreated sludge was governed by the falling rate period where drying flux decreased continuously as a function of sludge moisture content due to heat and mass transfer limitations and sample shrinkage. Hydrothermal treatment increased the drying flux of sludge hydrochar and decreased the effect of internal heat and mass transfer limitations and sample shrinkage especially at higher treatment temperatures. The determined effective moisture diffusivities of sludge and hydrochar increased as a function of decreasing moisture content and the mean diffusivity of untreated sludge (8.56·10(-9) m(2) s(-1)) and sludge hydrochar (12.7-27.5·10(-9) m(2) s(-1)) were found statistically different. The attained regression model indicated that treatment temperature governed the mean diffusivity of hydrochar, as the effects of NaOH and HCl were statistically insignificant. The attained results enabled prediction of sludge drying properties through mean moisture diffusivity based on hydrothermal treatment conditions. PMID:26773481

  9. Effect of the addition of calcium hydroxide on the hydrothermal-mechanochemical treatment of Eucalyptus.

    PubMed

    Ishiguro, Maki; Endo, Takashi

    2015-02-01

    The effect of Ca(OH)2 addition on optimization of hydrothermal-mechanochemical pretreatment, which combines hydrothermal and milling treatments, was examined. The highest glucose yield of 90% was achieved in the ball-milled specimen previously treated at 170°C in the presence of 20% Ca(OH)2 per substrate weight. The specific surface area of the substrate was closely correlated with glucose yield, and a larger specific surface area was obtained when treating the specimen at 170°C in the presence of Ca(OH)2 compared to treatment at 170°C without Ca(OH)2. Although the Ca(OH)2-treated specimen was relatively unaffected by delignification, the cleavage of the ester bonds between lignin and hemicellulose was confirmed by FT-IR. This suggests that Ca(OH)2 weakens the substrate structure by loosening the bonds between lignin and hemicellulose as the mechanism to increase the specific surface area regardless of the high lignin content, facilitating the fibrillation of fibers with mechanical milling.

  10. Ecology of deep-sea hydrothermal vent communities: A review

    SciTech Connect

    Lutz, R.A.; Kennish, M.J. )

    1993-08-01

    The present article reviews studies of the past 15 years of active and inactive hydrothermal vents. The focus of the discussion is on the ecology of the biological communities inhabiting hydrothermal vents. These communities exhibit high densities and biomass, low species diversity, rapid growth rates, and high metabolic rates. The authors attempt to relate the biology of hydrothermal vent systems to geology. Future directions for hydrothermal vent research are suggested. Since many vent populations are dependent on hydrothermal fluids and are consequently unstable, both short- and long-term aspects of the ecology of the vent organisms and the influence of chemical and geological factors on the biology of vent systems need to be established. 200 refs., 28 figs.

  11. Hydrothermal synthesis of lutetium disilicate nanoparticles

    NASA Astrophysics Data System (ADS)

    Tang, Xiaoping; Gao, Yanfeng; Chen, Hongfei; Luo, Hongjie

    2012-04-01

    A simple, low-cost hydrothermal method was developed to synthesize irregular-and rod-shaped lutetium disilicate (Lu2Si2O7) powders with sizes ranging from 71 to 340 nm. The synthesis temperature was 260 °C, which is nearly 1300 °C lower than that required for the solid-state reaction. The results indicated that both the hydrothermal temperature and pH values had great influences on the composition, crystalline phase and morphology of the powders. The formation mechanism, basic thermophysical properties, stability and anticorrosion properties of the Lu2Si2O7 powders were also investigated. The obtained powders possessed low thermal conductivity, a suitable thermal expansion coefficient (3.92-5.17×10-6 K-1) with the silicon-based substrate and excellent thermal and structural stability. During hot corrosion testing, the surfaces of the samples appeared to react with the water and molten salt vapors, but no serious failure occurred.

  12. Hydrothermal Activity in the Northern Guaymas Basin

    NASA Astrophysics Data System (ADS)

    Berndt, C.; Hensen, C.; Mortera-Gutierrez, C. A.; Sarkar, S.; Geilert, S.; Schmidt, M.; Liebetrau, V.; Kipfer, R.; Scholz, F.; Doll, M.; Muff, S.; Karstens, J.; Böttner, C.; Chi, W. C.; Moser, M.; Behrendt, R.; Fiskal, A.; Evans, T.; Planke, S.; Lizarralde, D.; Lever, M. A.

    2015-12-01

    Rift-related magmatism in the Guaymas Basin, Gulf of California induces hydrothermal activity within the basin sediments. Mobilized fluids migrate to the seafloor where they are emitted into the water column changing ocean chemistry and fuelling chemosynthetic ecosystems. New seismic and geochemical data from the northern rift arm of the Guaymas Basin document the variety of fluid expulsion phenomena from large-scale subsurface sediment mobilization related to contact metamorphosis to focused small-scale structures. The geochemical composition of emitted fluids depends largely on the age of the fluid escape structures with respect to the underlying intrusions. Whereas, old structures are dominated by methane emission, young vent sites are characterized by hot fluids that carry a wide range of minerals in solution. The overall high geothermal gradient within the basin (mainly between 160 and 260 °C/km) leads to a thin gas hydrate stability zone. Thus, deep hydrothermal fluid advection affects the gas hydrate system and makes it more dynamic than in colder sedimentary basins.

  13. Nutritional strategies of the hydrothermal ecosystem bivalves

    NASA Astrophysics Data System (ADS)

    Le Pennec, Marcel; Donval, Anne; Herry, Angèle

    Studies of deep-sea hydrothermal bivalves have revealed that the species, which are strictly dependent upon the interstitial fluid emissions, derive their food indirectly via symbiotic relationships with chemosynthetic bacteria present in their gill tissues. As the gill plays the main trophic role, structural and ultrastructural modifications occur in the digestive tract. Scanning and transmission electron microscope studies reveal that the digestive system of species belonging to the genera Calyptogena, Bathymodiolus and Bathypecten have anatomical differences. In Calyptogena, the reduction of several parts of the digestive tract and the stomach content which is either empty or full, according to the various species examined indicate that the digestive system is hardly if at all functional. In Bathymodiolus, the labial palps are well developed, the stomach is always full with particles and the two cellular types, digestive and secretory, are present in the digestive gland. All these characteristics indicate that the digestive system is functional. In Bathypecten, the digestive tract is well developed and it seems that it plays the main trophic role. We conclude that the nutritional strategies of the hydrothermal vents bivalves are quite varied. They range from a normal trophic process, through a mixotrophic diet, to one based purely on chemoautotrophic bacteria. The strategy of each species is adapted to and influences its distribution.

  14. Compositional Variability of Rutile in Hydrothermal Ore Deposits

    NASA Astrophysics Data System (ADS)

    Clark, J. R.; Williams-Jones, A. E.

    2009-05-01

    overlaps between mineralization types. Nevertheless, element combinations and ratios can be used to distinguish qualitatively between rutile compositions for most ore deposit types, and statistical methods can be used to provide more quantitative evaluation. Rutile occurs in significant abundance (typically 0.05 to 0.5 vol%) in most metallic ore deposits and is most plentiful in sulfidic systems where high fS2 and/or fO2 conditions stabilize rutile in the presence of minerals such as pyrite and hematite. Rutile is also persistent in weathering environments, and is likely to survive transport by glacial and fluvial processes. As a common component of heavy mineral sands, rutile is readily separable by routine magnetic, heavy liquid, and other density methods. These features, combined with the sensitive compositional variations in altered and mineralized rocks noted above, and the relative ease of analyses by routine electron microprobe methods, suggest that rutile has considerable potential as a geochemical indicator mineral for hydrothermal ore deposits, analogous to the kimberlite indicator minerals such as Cr-pyrope, magnesiochromite and picroilmenite that are used regularly in diamond exploration.

  15. Hydrothermal circulation in fault slots with topography

    NASA Astrophysics Data System (ADS)

    Titarenko, Sofya; McCaig, Andrew

    2014-05-01

    There are numerous cases where the circulation of hydrothermal fluid is likely to be confined within a permeable fault slot. Examples are (1) the Lost City Hydrothermal Field (LCHF) at 30 N in the Atlantic, which is likely to be controlled by large E-W faults related to the Atlantis transform fault and mass wasting on the southern wall of the Atlantis Massif, and (2) large normal faults bounding the Hess Deep rift in the East Pacific, which contain intense hydrothermal metamorphic assemblages in lower crustal gabbros formed at 200-350 ° C. This type of circulation could occur anywhere where steep faults cut the oceanic crust, including large near-axis normal faults, transform faults and faults at subduction bend zones, and could be the major way in which the upper mantle and lower crust are hydrated. It is therefore important to constrain the controls on temperature conditions of alteration and hence mineral assemblages. Previous 2-D modelling of the LCHF shows that seafloor topography and permeability structure combine together to localise the field near the highest point of the Atlantis Massif. Our new models are 3-D, based on a 10km cube with seafloor topography of ~ 2km affecting both the fault slot and impermeable wall rocks. We have used Comsol multiphysics in this modelling, with a constant basal heatflow corresponding to the near conductive thermal gradient measured in IODP Hole 1309D, 5km north of the LCHF, and a constant temperature seafloor boundary condition. The wall rocks of the slot have a permeability of 10-17 m2 while permeability in the slot is varied between 10-14 and 10-15 m2. Initial conditions are a conductive thermal structure corresponding to the basal heatflow at steady state. Generic models not based on any particular known topography quickly stabilise a hydrothermal system in the fault slot with a single upflow zone close to the model edge with highest topography. In models with a depth of circulation in the fault slot of about 6 km

  16. Characteristics of Hydrothermal Mineralization in Ultraslow Spreading Ridges

    NASA Astrophysics Data System (ADS)

    Zhou, H.; Yang, Q.; Ji, F.; Dick, H. J.

    2014-12-01

    Hydrothermal activity is a major component of the processes that shape the composition and structure of the ocean crust, providing a major pathway for the exchange of heat and elements between the Earth's crust and oceans, and a locus for intense biological activity on the seafloor and underlying crust. In other hand, the structure and composition of hydrothermal systems are the result of complex interactions between heat sources, fluids, wall rocks, tectonic controls and even biological processes. Ultraslow spreading ridges, including the Southwest Indian Ridge, the Gakkel Ridge, are most remarkable end member in plate-boundary structures (Dick et al., 2003), featured with extensive tectonic amagmatic spreading and frequent exposure of peridotite and gabbro. With intensive surveys in last decades, it is suggested that ultraslow ridges are several times more effective than faster-spreading ridges in sustaining hydrothermal activities. This increased efficiency could attributed to deep mining of heat and even exothermic serpentinisation (Baker et al., 2004). Distinct from in faster spreading ridges, one characteristics of hydrothermal mineralization on seafloor in ultraslow spreading ridges, including the active Dragon Flag hydrothermal field at 49.6 degree of the Southwest Indian Ridge, is abundant and pervasive distribution of lower temperature precipitated minerals ( such as Fe-silica or silica, Mn (Fe) oxides, sepiolite, pyrite, marcasite etc. ) in hydrothermal fields. Structures formed by lower temperature activities in active and dead hydrothermal fields are also obviously. High temperature precipitated minerals such as chalcopyrite etc. are rare or very limited in hydrothermal chimneys. Distribution of diverse low temperature hydrothermal activities is consistence with the deep heating mechanisms and hydrothermal circulations in the complex background of ultraslow spreading tectonics. Meanwhile, deeper and larger mineralization at certain locations along the

  17. The effect of stirring in the hydrothermal process to convert the mixed municipal solid waste into uniform solid fuel

    NASA Astrophysics Data System (ADS)

    Prawisudha, P.; Mu'min, G. F.; Yoshikawa, K.; Pasek, A. D.

    2016-06-01

    An innovative waste treatment technology has been developed in Indonesia to treat the mixed municipal solid waste into a solid fuel by employing the hydrothermal process. A mixture of organic and plastic waste was treated in a 2.5 L reactor using saturated steam in the temperature range of 120 to 180 °C. Two modes of operation were employed to achieve two different goals, i.e. without stirring (NS mode) and with stirring (WS mode). It was observed that both modes resulted in increasing density of product up to twofold of the raw MSW. In NS mode, the processed mixed MSW was converted into two different products; however, in WS mode the bulky plastic was converted into small granules, producing a uniform product. The results suggest that by hydrothermal treatment, the organic fibers in the organic parts are trapped into the plastic, and the stirring breaks the bulky plastics, producing uniform granules suitable as solid fuel. Therefore, the stirring during the hydrothermal process can be a solution to treat the MSW as it is, without any separation, to produce a clean and renewable energy source.

  18. Reactive transport modeling of hydrothermal circulation in oceanic crust: effect of anhydrite precipitation on the dynamics of submarine hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Yang, J.

    2009-12-01

    Hydrothermal fluid circulation represents an extremely efficient mechanism for the exchange of heat and matter between seawater and oceanic crust. Precipitation and dissolution of minerals associated with hydrothermal flow at ridge axes can alter the crustal porosity and permeability and hence influence the dynamics of hydrothermal systems. In this study, a fully coupled fluid flow, heat transfer and reactive mass transport model was developed using TOUGHREACT to evaluate the role of mineral precipitation and dissolution on the evolution of hydrothermal flow systems, with a particular attention focused on anhydrite precipitation upon heating of seawater in recharge zones and the resultant change in the crustal porosity and permeability. A series of numerical case studies were carried out to assess the effect of temperature and aqueous phase inflow concentrations on the reactive geochemical system. The impact of chemically induced porosity and permeability changes on the dynamics of hydrothermal systems was also addressed.

  19. The Guaymas Basin Hiking Guide to Hydrothermal Mounds, Chimneys, and Microbial Mats: Complex Seafloor Expressions of Subsurface Hydrothermal Circulation.

    PubMed

    Teske, Andreas; de Beer, Dirk; McKay, Luke J; Tivey, Margaret K; Biddle, Jennifer F; Hoer, Daniel; Lloyd, Karen G; Lever, Mark A; Røy, Hans; Albert, Daniel B; Mendlovitz, Howard P; MacGregor, Barbara J

    2016-01-01

    The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview, we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbial communities and activities. Microprofiler deployments on microbial mats and hydrothermal sediments show their steep geochemical and thermal gradients at millimeter-scale vertical resolution. Mapping these hydrothermal features and sampling locations within the southern Guaymas Basin suggest linkages to underlying shallow sills and heat flow gradients. Recognizing the inherent spatial limitations of much current Guaymas Basin sampling calls for comprehensive surveys of the wider spreading region.

  20. The Guaymas Basin Hiking Guide to Hydrothermal Mounds, Chimneys, and Microbial Mats: Complex Seafloor Expressions of Subsurface Hydrothermal Circulation

    PubMed Central

    Teske, Andreas; de Beer, Dirk; McKay, Luke J.; Tivey, Margaret K.; Biddle, Jennifer F.; Hoer, Daniel; Lloyd, Karen G.; Lever, Mark A.; Røy, Hans; Albert, Daniel B.; Mendlovitz, Howard P.; MacGregor, Barbara J.

    2016-01-01

    The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview, we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbial communities and activities. Microprofiler deployments on microbial mats and hydrothermal sediments show their steep geochemical and thermal gradients at millimeter-scale vertical resolution. Mapping these hydrothermal features and sampling locations within the southern Guaymas Basin suggest linkages to underlying shallow sills and heat flow gradients. Recognizing the inherent spatial limitations of much current Guaymas Basin sampling calls for comprehensive surveys of the wider spreading region. PMID:26925032

  1. The Guaymas Basin Hiking Guide to Hydrothermal Mounds, Chimneys, and Microbial Mats: Complex Seafloor Expressions of Subsurface Hydrothermal Circulation.

    PubMed

    Teske, Andreas; de Beer, Dirk; McKay, Luke J; Tivey, Margaret K; Biddle, Jennifer F; Hoer, Daniel; Lloyd, Karen G; Lever, Mark A; Røy, Hans; Albert, Daniel B; Mendlovitz, Howard P; MacGregor, Barbara J

    2016-01-01

    The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview, we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbial communities and activities. Microprofiler deployments on microbial mats and hydrothermal sediments show their steep geochemical and thermal gradients at millimeter-scale vertical resolution. Mapping these hydrothermal features and sampling locations within the southern Guaymas Basin suggest linkages to underlying shallow sills and heat flow gradients. Recognizing the inherent spatial limitations of much current Guaymas Basin sampling calls for comprehensive surveys of the wider spreading region. PMID:26925032

  2. Subaqueous cryptodome eruption, hydrothermal activity and related seafloor morphologies on the andesitic North Su volcano

    NASA Astrophysics Data System (ADS)

    Thal, Janis; Tivey, Maurice; Yoerger, Dana R.; Bach, Wolfgang

    2016-09-01

    North Su is a double-peaked active andesite submarine volcano located in the eastern Manus Basin of the Bismarck Sea that reaches a depth of 1154 m. It hosts a vigorous and varied hydrothermal system with black and white smoker vents along with several areas of diffuse venting and deposits of native sulfur. Geologic mapping based on ROV observations from 2006 and 2011 combined with morphologic features identified from repeated bathymetric surveys in 2002 and 2011 documents the emplacement of a volcanic cryptodome between 2006 and 2011. We use our observations and rock analyses to interpret an eruption scenario where highly viscous, crystal-rich andesitic magma erupted slowly into the water-saturated, gravel-dominated slope of North Su. An intense fragmentation process produced abundant blocky clasts of a heterogeneous magma (olivine crystals within a rhyolitic groundmass) that only rarely breached through the clastic cover onto the seafloor. Phreatic and phreatomagmatic explosions beneath the seafloor cause mixing of juvenile and pre-existing lithic clasts and produce a volcaniclastic deposit. This volcaniclastic deposit consists of blocky, non-altered clasts next, variably (1-100%) altered clasts, hydrothermal precipitates and crystal fragments. The usually applied parameters to identify juvenile subaqueous lava fragments, i.e. fluidal shape or chilled margin, were not applicable to distinguish between pre-existing non-altered clasts and juvenile clasts. This deposit is updomed during further injection of magma and mechanical disruption. Gas-propelled turbulent clast-recycling causes clasts to develop variably rounded shapes. An abundance of blocky clasts and the lack of clasts typical for the contact of liquid lava with water is interpreted to be the result of a cooled, high-viscosity, crystal-rich magma that failed as a brittle solid upon stress. The high viscosity allows the lava to form blocky and short lobes. The pervasive volcaniclastic cover on North Su is

  3. In Situ Raman Spectra from the SeaCliff Hydrothermal Field (Gorda Ridge)

    NASA Astrophysics Data System (ADS)

    White, S. N.; Dunk, R. M.; Brewer, P. G.; Peltzer, E. T.; Sherman, A. D.; Freeman, J. J.

    2004-12-01

    MBARI's in situ laser Raman spectrometer (DORISS - Deep Ocean Raman In Situ Spectrometer) was deployed at the SeaCliff Hydrothermal Field on the Gorda Ridge in July 2004. The first in situ Raman spectra of hydrothermal minerals and high-temperature fluid venting from the seafloor were obtained. These spectra are analyzed and compared to laboratory measurements of samples collected from the site. Laser Raman spectroscopy is a proven, powerful geochemical technique for analyzing the chemical composition and molecular structure of solids, liquids, and gases. During an expedition to Gorda Ridge on the R/V Western Flyer in July 2004, DORISS was deployed successfully by the ROV Tiburon at hydrothermal vents on the seafloor ( ˜2700 m depth). Data were collected from hydrothermal fluids, chimney minerals (e.g., anhydrite and barite), and bacterial mats using two types of sampling optics: an immersion optic, and a non-contact optic. To collect spectra from opaque mineral samples, a precision underwater positioner (PUP) was used to position the DORISS probe head. PUP is a stand-alone, three degree-of-freedom positioner capable of moving the DORISS probe head with a precision of 0.1 mm (required by the small focal volume of the sampling optic). Raman spectra were collected of ˜300° C vent fluids with both sampling optics. The Raman spectrum of seawater contains bands from the bending ( ˜1640 cm-1) and stretching (3000-3700 cm-1) vibrational modes of the water molecule and a small peak from the S-O stretch of the sulfate ion ( ˜981 cm-1). Compared to ˜2° C ambient seawater, vent fluid spectra show changes in the intensity ratios of the water bands due to the elevated temperature, and the sulfate peak is reduced. Additional components of hydrothermal fluid are present in such low concentrations that it is difficult to detect them with the current Raman system. The chimneys in the SeaCliff field are primarily anhydrite, and debris in the area also contains barite. We were

  4. Effects of glacial ice on subsurface temperatures of hydrothermal systems in Yellowstone National Park, Wyoming: Fluid-inclusion evidence

    SciTech Connect

    Bargar, K.E.; Fournier, R.O. )

    1988-12-01

    Hydrothermal quartz and fluorite crystals containing liquid-rich fluid inclusions (coexisting vapor-rich fluid inclusions were not observed) were found in drill cores from eight relatively shallow research holes drilled by the US Geological Survey in and near major geyser basins of Yellowstone National Park. Homogenization temperatures (T{sub h}) for mostly secondary fluid inclusions show variations in temperature that have occurred at give depths since precipitation of the host minerals. Within major hydrothermal upflow zones, fluid-inclusion T{sub h} values all were found to be equal to or higher (commonly 20-50 C and up to 155 C higher) than present temperatures at the depths sampled. During periods when thick glacial ice covered the Yellowstone National Park region, pore-fluid pressures in the underlying rock were increased in proportion to the weight of the overlying column of ice. Accordingly, theoretical reference boiling-point curves that reflect the maximum temperature attainable in a hot-water geothermal system at a given depth were elevated, and temperatures within zones of major hydrothermal upflow (drill holes Y-2, Y-3, Y-6, Y-11, Y-13, and upper part of Y-5) increased. The thicknesses of ice required to elevate boiling-point curves sufficiently to account for the observed fluid-inclusion T{sub h} values are within the ranges estimated by glacial geologic studies. At the margins of major hydrothermal upflow zones (drill holes Y-4 and Y-9), fluid-inclusion T{sub h} values at given depths range from 57 C lower to about the same as the current temperature measurements because of a previous decrease in the rate of discharge of warm water and/or an increase in the rate of recharge of cold water into the hydrothermal system.

  5. Vapor-phase hydrothermal transformation of HTiOF3 intermediates into {001} faceted anatase single-crystalline nanosheets.

    PubMed

    Liu, Porun; Wang, Yun; Zhang, Haimin; An, Taicheng; Yang, Huagui; Tang, Zhiyong; Cai, Weiping; Zhao, Huijun

    2012-12-01

    For the first time, a facile, one-pot hydrofluoric acid vapor-phase hydrothermal (HF-VPH) method is demonstrated to directly grow single-crystalline anatase TiO(2) nanosheets with 98.2% of exposed {001} faceted surfaces on the Ti substrate via a distinctive two-stage formation mechanism. The first stage produces a new intermediate crystal (orthorhombic HTiOF(3) ) that is transformed into anatase TiO(2) nanosheets during the second stage. The findings reveal that the HF-VPH reaction environment is unique and differs remarkably from that of liquid-phase hydrothermal processes. The uniqueness of the HF-VPH conditions can be readily used to effectively control the nanostructure growth. PMID:22903795

  6. Entropy Production in Convective Hydrothermal Systems

    NASA Astrophysics Data System (ADS)

    Boersing, Nele; Wellmann, Florian; Niederau, Jan

    2016-04-01

    Exploring hydrothermal reservoirs requires reliable estimates of subsurface temperatures to delineate favorable locations of boreholes. It is therefore of fundamental and practical importance to understand the thermodynamic behavior of the system in order to predict its performance with numerical studies. To this end, the thermodynamic measure of entropy production is considered as a useful abstraction tool to characterize the convective state of a system since it accounts for dissipative heat processes and gives insight into the system's average behavior in a statistical sense. Solving the underlying conservation principles of a convective hydrothermal system is sensitive to initial conditions and boundary conditions which in turn are prone to uncertain knowledge in subsurface parameters. There exist multiple numerical solutions to the mathematical description of a convective system and the prediction becomes even more challenging as the vigor of convection increases. Thus, the variety of possible modes contained in such highly non-linear problems needs to be quantified. A synthetic study is carried out to simulate fluid flow and heat transfer in a finite porous layer heated from below. Various two-dimensional models are created such that their corresponding Rayleigh numbers lie in a range from the sub-critical linear to the supercritical non-linear regime, that is purely conductive to convection-dominated systems. Entropy production is found to describe the transient evolution of convective processes fairly well and can be used to identify thermodynamic equilibrium. Additionally, varying the aspect ratio for each Rayleigh number shows that the variety of realized convection modes increases with both larger aspect ratio and higher Rayleigh number. This phenomenon is also reflected by an enlarged spread of entropy production for the realized modes. Consequently, the Rayleigh number can be correlated to the magnitude of entropy production. In cases of moderate

  7. The Sasquatch Hydrothermal Field: Linkages Between Seismic Activity, Hydrothermal Flow, and Geology

    NASA Astrophysics Data System (ADS)

    Glickson, D. A.; Kelley, D. S.; Delaney, J. R.

    2006-12-01

    The Sasquatch Hydrothermal Field is the most northern known vent field along the central Endeavour Segment of the Juan de Fuca Ridge, located 6 km north of the Main Endeavour Field (MEF) near 47° 59.8'N, 129° 4.0'W. It was discovered in 2000, after two large earthquake swarms in June 1999 and January 2000 caused increased venting temperatures in the MEF and significant changes in volatile composition along the entire axis [Johnson et al., 2000; Lilley et al., 2003; Proskurowski et al., 2004]. From 2004-2006, Sasquatch and the surrounding axial valley were comprehensively mapped with SM2000 multibeam sonar system and Imagenex scanning sonar at a resolution of 1-5 m. These data were combined with visual imagery from Alvin and ROV dives to define the eruptive, hydrothermal, and tectonic characteristics of the field and distal areas. Based on multibeam sonar results, bathymetric relief of the segment near Sasquatch is subdued. The broad axial valley is split by a central high that rises 30-40 m above the surrounding seafloor. Simple pattern analysis of the valley shows two fundamentally different regions, distinguished by low and high local variance. Areas of low variance correspond to a collapse/drainback landscape characterized by ropy sheet flow, basalt pillars, and bathtub rings capped by intact and drained lobate flows. Areas of high variance generally correspond to three types of ridge structures: 1) faulted basalt ridges composed of truncated pillow basalt, rare massive flows, and widespread pillow talus; 2) constructional basalt ridges composed of intact pillow flow fronts; and 3) extinct sulfide ridges covered by varying amounts of sulfide talus and oxidized hydrothermal sediment. Sasquatch is located in a depression among truncated pillow ridges, and is comprised of ~10, 1-6 m high, fragile sulfide chimneys that vent fluids up to 289°C. The active field extends only ~25 x 25 m, although a linear, N-S trending ridge of nearly continuous extinct sulfide

  8. Treating oilfield emulsions

    SciTech Connect

    Not Available

    1990-01-01

    This book is divided into the following sections: The Treating Problem of Oilfield Emulsion; The Theory of Emulsions; Emulsions and Production Practices; The Basic Principles of Treating; The Application of Heat in Treating; The Principles of Chemical Treating; Treating with Heater-Treaters; Automatic Central Oil-Treating Systems; Sampling Procedures; Testing for Sediment and Water; Treating Cost Records.

  9. Geochemistry of hydrothermal plume in the Suiyo Seamount Caldera.

    NASA Astrophysics Data System (ADS)

    Shitashima, K.; Maeda, Y.

    2002-12-01

    Chemical compounds of the hot basalt origin are discharged into the deep ocean via hydrothermal plume by the deep-sea hydrothermal activity. The hydrothermal plume is widely diffused to the ocean by mixing with ambient seawater. Chemical reactions and interactions with microorganisms in the diffusion process of the hydrothermal plume are important to comprehend the oceanic geochemical cycles. Recently, it has been clarified that the variation of hydrothermal activity is greatly controlled in the tidal current. Not only geochemical observation but also physical observation, such as water current measurement, are necessary for the understanding of the deep-sea hydrothermal systems including the behavior of hydrothermal plume. In order to observe the diffusion process of hydrothermal plumes, sampling and chemical mapping of the hydrothermal plume and measurement of water current were carried out at the Suiyo Seamount Caldera during research cruises under the ?Archaean Park? project funded by MEXT. The three-dimensional acoustic current meters were moored at the height of 13m and 125m above the bottom in the Suiyo Seamount Caldera. At the 13m height, average water current speed and current direction were 10.46 cm/second and 228.1 degrees, respectively, and maximum water current speed was over 40.46 cm/second. On the other hand, average water current speed and current direction at the 125m height were 3.87 cm/second and 57.8 degrees, respectively. The strong water current of the southwest direction in 24 hours periods existed near bottom of the caldera. In addition, downward current and water temperature depreciation were observed, when there was the strong current in 24 hours periods. These results suggest that the low-temperature ocean water around the Suiyo Seamount flows toward the bottom of caldera periodically. The mini CTDT-RMS mounted twelve 1.2L Niskin bottles and the in-situ pH sensor were installed on the ROV or manned submersible. The hydrothermal plume

  10. Impact-induced hydrothermal activity within the Haughton impact structure, arctic Canada: generation of a transient, warm, wet oasis

    NASA Astrophysics Data System (ADS)

    Osinski, Gordon R.; Spray, John G.

    2001-05-01

    Field studies and analytical scanning electron microscopy indicate that a hydrothermal system was created by the interaction of water with hot, impact-generated rocks following formation of the 24 km-diameter, 23 Ma Haughton impact structure. Hydrothermal alteration is recognized in two settings: within polymict impact breccias overlying the central portion of the structure, and within localized pipes in impact-generated concentric fault systems. The intra-breccia alteration comprises three varieties of cavity and fracture filling: (a) sulfide with carbonate, (b) sulfate, and (c) carbonate. These are accompanied by subordinate celestite, barite, fluorite, quartz and marcasite. Selenite is also developed, particularly in the lower levels of the impact breccia sheet. The fault-related hydrothermal alteration occurs in 1-7 m diameter subvertical pipes that are exposed for lengths of up 20 m. The pipes are defined by a monomict quartz-carbonate breccia showing pronounced Fe-hydroxide alteration. Associated sulfides include marcasite, pyrite and chalcopyrite. We propose three distinct stages in the evolution of the hydrothermal system: (1) Early Stage (>200 degC), with the precipitation of quartz (vapour phase dominated); (2) Main Stage (200-100 deg C), with the development of a two phase (vapour plus liquid) zone, leading to calcite, celestite, barite, marcasite and fluorite precipitation, and (3) Late Stage (<100 degC), with selenite and fibroferrite development through liquid phase-dominanted precipitation. We estimate that it took several tens of thousands of years to cool below 50 deg C following impact. During this time, Haughton supported a 14 km diameter crater lake and subsurface water system, providing a warmer, wetter niche relative to the surrounding terrain. The results also reveal how understanding the internal structure of impact craters is necessary in order to determine their plumbing and cooling systems.

  11. Quartz precipitation and fluid inclusion characteristics in sub-seafloor hydrothermal systems associated with volcanogenic massive sulfide deposits

    NASA Astrophysics Data System (ADS)

    Steele-MacInnis, Matthew; Han, Liang; Lowell, Robert P.; Rimstidt, J. Donald; Bodnar, Robert J.

    2012-06-01

    Results of a numerical modeling study of quartz dissolution and precipitation in a sub-seafloor hydrothermal system have been used to predict where in the system quartz could be deposited and potentially trap fluid inclusions. The spatial distribution of zones of quartz dissolution and precipitation is complex, owing to the fact that quartz solubility depends on many inter-related factors, including temperature, fluid salinity and fluid immiscibility, and is further complicated by the fact that quartz exhibits both prograde and retrograde solubility behavior, depending on the fluid temperature and salinity. Using the PVTX properties of H2O-NaCl, the petrographic and microthermometric properties of fluid inclusions trapped at various locations within the hydrothermal system have been predicted. Vapor-rich inclusions are trapped as a result of the retrograde temperature-dependence of quartz solubility as the convecting fluid is heated in the vicinity of the magmatic heat source. Coexisting liquid-rich and vapor-rich inclusions are also trapped in this region when quartz precipitates as a result of fluid immiscibility that lowers the overall bulk quartz solubility in the system. Fluid inclusions trapped in the shallow subsurface near the seafloor vents and in the underlying stockwork are liquid-rich with homogenization temperatures of 200-400°C and salinities close to that of seawater. Volcanogenic massive sulfide (VMS) deposits represent the uplifted and partially eroded remnants of fossil submarine hydrothermal systems, and the relationship between fluid-inclusion properties and location within the hydrothermal system described here can be used in exploration for VMS deposits to infer the direction towards potential massive sulfide ore.

  12. Hydrothermal contribution to the oceanic dissolved iron inventory

    NASA Astrophysics Data System (ADS)

    Tagliabue, Alessandro; Bopp, Laurent; Dutay, Jean-Claude; Bowie, Andrew R.; Chever, Fanny; Jean-Baptiste, Philippe; Bucciarelli, Eva; Lannuzel, Delphine; Remenyi, Tomas; Sarthou, Géraldine; Aumont, Olivier; Gehlen, Marion; Jeandel, Catherine

    2010-04-01

    Iron limits phytoplankton growth and hence the biological carbon pump in the Southern Ocean. Models assessing the impacts of iron on the global carbon cycle generally rely on dust input and sediment resuspension as the predominant sources. Although it was previously thought that most iron from deep-ocean hydrothermal activity was inaccessible to phytoplankton because of the formation of particulates, it has been suggested that iron from hydrothermal activity may be an important source of oceanic dissolved iron. Here we use a global ocean model to assess the impacts of an annual dissolved iron flux of approximately 9×108mol, as estimated from regional observations of hydrothermal activity, on the dissolved iron inventory of the world's oceans. We find the response to the input of hydrothermal dissolved iron is greatest in the Southern Hemisphere oceans. In particular, observations of the distribution of dissolved iron in the Southern Ocean (Chever et al., manuscript in preparation; Bowie et al., manuscript in preparation) can be replicated in our simulations only when our estimated iron flux from hydrothermal sources is included. As the hydrothermal flux of iron is relatively constant over millennial timescales, we propose that hydrothermal activity can buffer the oceanic dissolved iron inventory against shorter-term fluctuations in dust deposition.

  13. Effects of hydrothermal treatment with CaCl(2) solution on surface property and cell response of titanium implants.

    PubMed

    Nakagawa, M; Zhang, L; Udoh, K; Matsuya, S; Ishikawa, K

    2005-11-01

    In order to obtain early and good osteointegration after implantation of a titanium implant in the human body, the surface modified treatments using NaOH or H(2)O(2) etc. were reported. In this study, titanium was hydrothermally treated with CaCl(2) solutions at 200 degrees C for 24hr (CaCl(2)-HT). Scanning electron microscope (SEM) observation clearly showed apatite deposition on the surface of CaCl(2) HT treated titanium faster than other chemical treated titanium immersion in simulated body fluid. X-ray photoelectron spectroscopy (XPS) analysis demonstrated that Ti--O--Ca bonding was formed on titanium surface by hydrothermal treatment with CaCl(2) solution. And it was revealed that thickness of TiO(2), which was known to play important roles for the formation of bone-like apatite, became approximately three times thicker than as-polished titanium. The amount of initial attached MC3T3-E1 cells on as-polished and NaOH, H(2)O(2) and this CaCl(2) HT treated titanium were almost the same values. After 5 days incubation, the growth rate of MC3T3-E1 cells on CaCl(2)-HT treated titanium was significantly higher than that on other chemical treated titanium. The hydrothermal treatment with 10-20 mmol/L CaCl(2) solution at 200 degrees C was an effective method for the fabrication of titanium implant with good bioactivity and osteoconductivity.

  14. Hydrothermal synthesis of vanadium pentoxide nanowires

    NASA Astrophysics Data System (ADS)

    Kumar, J. Santhosh; Thangadurai, P.

    2016-05-01

    Nanowires of V2O5 were prepared via hydrothermal route using NH4VO3 as precursor in the presence of sulfuric acid at 120°C for 24 h. This synthesis process is free of any templates and reducing agents. Thermal analysis showed a phase change at 350°C and the samples were annealed at 500°C. The XRD analysis showed the monoclinic phase for the as-prepared and orthorhombic phase of V2O5 when annealed at 500°C. Characteristic Raman peaks also expressed the same structural features. Microstructure analysis by SEM showed the nanowire structure of V2O5 with thickness in the range of 20-50 nm and length in micrometers. The possible mechanisms of formation of the nanowires were schematically explained based on the layered structure of V2O5.

  15. Hydrothermal Gelation of Aqueous Cellulose Nanocrystal Suspensions.

    PubMed

    Lewis, Lev; Derakhshandeh, Maziar; Hatzikiriakos, Savvas G; Hamad, Wadood Y; MacLachlan, Mark J

    2016-08-01

    We report the facile preparation of gels from the hydrothermal treatment of suspensions of cellulose nanocrystals (CNCs). The properties of the hydrogels have been investigated by rheology, electron microscopy, and spectroscopy with respect to variation in the temperature, time, and CNC concentration used in preparation. Desulfation of the CNCs at high temperature appears to be responsible for the gelation of the CNCs, giving highly porous networks. The viscosity and storage modulus of the gels was shown to increase when samples were prepared at higher treatment temperature. Considering the wide natural abundance and biocompatibility of CNCs, this simple, green approach to CNC-based hydrogels is attractive for producing materials that can be used in drug delivery, insulation, and as tissue scaffolds. PMID:27467200

  16. Sulfur speciation in natural hydrothermal waters, Iceland

    NASA Astrophysics Data System (ADS)

    Kaasalainen, Hanna; Stefánsson, Andri

    2011-05-01

    The speciation of aqueous dissolved sulfur was determined in hydrothermal waters in Iceland. The waters sampled included hot springs, acid-sulfate pools and mud pots, sub-boiling well discharges and two-phase wells. The water temperatures ranged from 4 to 210 °C, the pH T was between 2.20 and 9.30 at the discharge temperature and the SO 4 and Cl concentrations were 0.020-52.7 and <0.01-10.0 mmol kg -1, respectively. The analyses were carried out on-site within ˜10 min of sampling using ion chromatography (IC) for sulfate (SO 42-), thiosulfate (S 2O 32-) and polythionates (S xO 62-) and titration and/or colorimetry for total dissolved sulfide (S 2-). Sulfite (SO 32-) could also be determined in a few cases using IC. Alternatively, for few samples in remote locations the sulfur oxyanions were stabilized on a resin on site following elution and analysis by IC in the laboratory. Dissolved sulfate and with few exceptions also S 2- were detected in all samples with concentrations of 0.02-52.7 mmol kg -1 and <1-4100 μmol kg -1, respectively. Thiosulfate was detected in 49 samples of the 73 analyzed with concentrations in the range of <1-394 μmol kg -1 (S-equivalents). Sulfite was detected in few samples with concentrations in the range of <1-3 μmol kg -1. Thiosulfate and SO 32- were not detected in <100 °C well waters and S 2O 32- was observed only at low concentrations (<1-8 μmol kg -1) in ˜200 °C well waters. In alkaline and neutral pH hot springs, S 2O 32- was present in significant concentrations sometimes corresponding to up to 23% of total dissolved sulfur (S TOT). In steam-heated acid-sulfate waters, S 2O 32- was not a significant sulfur species. The results demonstrate that S 2O 32- and SO 32- do not occur in the deeper parts of <150 °C hydrothermal systems and only in trace concentrations in ˜200-300 °C systems. Upon ascent to the surface and mixing with oxygenated ground and surface waters and/or dissolution of atmospheric O 2, S 2- is degassed and

  17. CONCEPTUAL MODELS FOR THE LASSEN HYDROTHERMAL SYSTEM.

    USGS Publications Warehouse

    Ingebritsen, S.E.; Sorey, M.L.

    1987-01-01

    The Lassen hydrothermal system, like a number of other systems in regions of moderate to great topographic relief, includes steam-heated features at higher elevations and high-chloride springs at lower elevations, connected to and fed by a single circulation system at depth. Two conceptual models for such systems are presented. They are similar in several ways: however, there are basic differences in terms of the nature and extent of vapor-dominated conditions beneath the steam-heated features. For some Lassen-like systems, these differences could have environmental and economic implications. Available data do not make it possible to establish a single preferred model for the Lassen system, and the actual system is complex enough that both models may apply to different parts of the system.

  18. Deep-Sea Hydrothermal-Vent Sampler

    NASA Technical Reports Server (NTRS)

    Behar, Alberto E.; Venkateswaran, Kasthur; Matthews, Jaret B.

    2008-01-01

    An apparatus is being developed for sampling water for signs of microbial life in an ocean hydrothermal vent at a depth of as much as 6.5 km. Heretofore, evidence of microbial life in deep-sea hydrothermal vents has been elusive and difficult to validate. Because of the extreme conditions in these environments (high pressures and temperatures often in excess of 300 C), deep-sea hydrothermal- vent samplers must be robust. Because of the presumed low density of biomass of these environments, samplers must be capable of collecting water samples of significant volume. It is also essential to prevent contamination of samples by microbes entrained from surrounding waters. Prior to the development of the present apparatus, no sampling device was capable of satisfying these requirements. The apparatus (see figure) includes an intake equipped with a temperature probe, plus several other temperature probes located away from the intake. The readings from the temperature probes are utilized in conjunction with readings from flowmeters to determine the position of the intake relative to the hydrothermal plume and, thereby, to position the intake to sample directly from the plume. Because it is necessary to collect large samples of water in order to obtain sufficient microbial biomass but it is not practical to retain all the water from the samples, four filter arrays are used to concentrate the microbial biomass (which is assumed to consist of particles larger than 0.2 m) into smaller volumes. The apparatus can collect multiple samples per dive and is designed to process a total volume of 10 L of vent fluid, of which most passes through the filters, leaving a total possibly-microbe-containing sample volume of 200 mL remaining in filters. A rigid titanium nose at the intake is used for cooling the sample water before it enters a flexible inlet hose connected to a pump. As the water passes through the titanium nose, it must be cooled to a temperature that is above a mineral

  19. Aqueous Volatiles in Lau Basin Hydrothermal Fluids

    NASA Astrophysics Data System (ADS)

    Seewald, J.; McCollom, T.; Proskurowski, G.; Reeves, E.; Mottl, M.; Sharkey, J.; Wheat, C. G.; Tivey, M.

    2005-12-01

    The Lau Basin is a back-arc spreading center characterized by widespread hydrothermal activity. High and low temperature vent fluids were collected from six vent fields along the Eastern Lau Spreading Center (ELSC) and the Valu Fa Ridge (VFR) using isobaric gas-tight samplers during R/V Melville cruise TUIM05MV. Fluids were analyzed for the abundances of H2, H2S, CH4, CO2, and CO to assess chemical environments inhabited by biological vent communities and constrain fluid-rock reactions and magmatic processes in subsurface environments. Maximum measured temperatures for focused venting in these areas varied from 309 to 363°C. Water depths decreased from ~2700m for sites sampled at the northern end of the ELSC to ~1725m for the southern most site sampled on the VFR. Endmember concentrations of dissolved H2 at the Kilo Moana, TowCam, and ABE vent fields on the ELSC varied from 0.054 to 0.498 mmol/l and showed a systematic interfield decrease from north to south along the ridge crest. A similar spatial trend was observed for endmember H2S concentrations that varied from 2.6 to 6.6 mmol/l. In contrast to H2 and H2S, aqueous CH4 abundances that varied from 0.028 to 0.057 mmol/l increased from north to south. In general, fluids from the Tui Malila, Mariner, and Vai Lili vent fields on the VFR showed greater compositional variability than fluids venting along the ELSC and an absence of systematic along strike chemical trends. Endmember H2, H2S, and CH4 abundances at VFR ranged from 0.0029 to 0.178 mmol/l, 0.010 to 9.6 mmol/l, and 0.0029 to 0.043 mmol/l, respectively. Endmember concentrations of dissolved CO at ELSC and VFR varied from 0.01 to 0.1 umol/l and showed systematic variations with dissolved H2 and CO2 abundances. Assessment of the CO, CO2, and H2 concentrations within a thermodynamic framework suggests that these species have attained equilibrium states at measured vent temperatures and pressures. The higher degree of compositional variability observed in vents

  20. Hydraulic characterization of hydrothermally altered Nopal tuff

    SciTech Connect

    Green, R.T.; Meyer-James, K.A.; Rice, G.

    1995-07-01

    Understanding the mechanics of variably saturated flow in fractured-porous media is of fundamental importance to evaluating the isolation performance of the proposed high-level radioactive waste repository for the Yucca Mountain site. Developing that understanding must be founded on the analysis and interpretation of laboratory and field data. This report presents an analysis of the unsaturated hydraulic properties of tuff cores from the Pena Blanca natural analog site in Mexico. The basic intent of the analysis was to examine possible trends and relationships between the hydraulic properties and the degree of hydrothermal alteration exhibited by the tuff samples. These data were used in flow simulations to evaluate the significance of a particular conceptual (composite) model and of distinct hydraulic properties on the rate and nature of water flow.

  1. Methane and radioactive isotopes in submarine hydrothermal systems

    SciTech Connect

    Kim, K.R.

    1983-01-01

    This thesis consists of two parts: 1) methane and 2) radioactive isotopes, especially radon, in submarine hydrothermal systems. Both parts deal with the use of these gases as tracers for mapping hydrothermal vents at sea, and with their relationships to other sensitive tracers such as helium, manganese, and temperature. Hydrothermal methane was used as a real-time tracer for locating new submarine hydrothermal systems along spreading axes, discovering new hydrothermal systems at two locations in Pacific Ocean: 1) 20/sup 0/S on East Pacific Rise, and 2) Mariana Trough Back-arc Basin. Methane shows good correlations with helium-3 and temperature with similar ratios in various hydrothermal systems, 3 to 42 x 10/sup 6/ for the methane to helium-3 ratio, and 3 to 19 ..mu.. cc/kg/sup 0/C for the methane to temperature anomaly. These similar ratios from different areas provide evidence for chemical homogeneity of submarine hydrothermal waters. A good correlation between methane and manganese appears to be associated only with high-temperature hydrothermal systems. Radioisotopes in the vent waters of 21/sup 0/N high-temperature hydrothermal system have end-member concentrations of 7.5 to 40 dpm/kg for Ra-226, 360 dpm/kg for Rn 222, 62 dpm/kg for Pb-210, and 19 dpm/kg for Po-210. The radon activity for this system is one order of magnitude lower, and the Pb-210 activity is one order or magnitude higher, than those a the low temperature Galapagos system. All these observations suggest that the high radon, and low Pb-210 activity observed in Galapagos system may originate from the extensive subsurface mixing and water-rock interaction in this system (direct injection of radon and scavenging of Pb-210).

  2. Permeability reduction in granite under hydrothermal conditions

    USGS Publications Warehouse

    Morrow, C.A.; Moore, Diane E.; Lockner, D.A.

    2001-01-01

    The formation of impermeable fault seals between earthquake events is a feature of many models of earthquake generation, suggesting that earthquake recurrence may depend in part on the rate of permeability reduction of fault zone materials under hydrothermal conditions. In this study, permeability measurements were conducted on intact, fractured, and gouge-bearing Westerly granite at an effective pressure of 50 MPa and at temperatures from 150?? to 500??C, simulating conditions in the earthquake-generating portions of fault zones. Pore fluids were cycled back and forth under a 2 MPa pressure differential for periods of up to 40 days. Permeability of the granite decreased with time t, following the exponential relation k = c(10-rt). For intact samples run between 250?? and 500??C the time constant for permeability decrease r was proportional to temperature and ranged between 0.001 and 0.1 days-1 (i.e., between 0.4 and 40 decades year-1 loss of permeability). Values of r for the lower-temperature experiments differed little from the 250??C runs. In contrast, prefractured samples showed higher rates of permeability decrease at a given temperature. The surfaces of the fractured samples showed evidence of dissolution and mineral growth that increased in abundance with both temperature and time. The experimentally grown mineral assemblages varied with temperature and were consistent with a rock-dominated hydrothermal system. As such mineral deposits progressively seal the fractured samples, their rates of permeability decrease approach the rates for intact rocks at the same temperature. These results place constraints on models of precipitation sealing and suggest that fault rocks may seal at a rate consistent with earthquake recurrence intervals of typical fault zones.

  3. Peptide synthesis under Enceladus hydrothermal condition

    NASA Astrophysics Data System (ADS)

    Fujishima, Kosuke; Takano, Yoshinori; Takai, Ken; Takahagi, Wataru; Adachi, Keito; Shibuya, Takazo; Tomita, Masaru

    2016-07-01

    Enceladus is one of the moons of Saturn, and it has been known to harbor interior ocean beneath the icy crust. The mass spectrometry data obtained by Cassini spacecraft indicates the presence of salty, and most likely alkaline ocean containing various organic compounds. While geochemical and other radiation related processes for in situ production of organics remain elusive, thermally unaltered carbonaceous chondrites, consisting the main body of Enceladus are known to be enriched with organic matters potentially including the building blocks of life (e.g., amino acids and amino acid precursors). Assuming that abiotic amino acids exist in the Enceladus alkaline seawater, we hypothesized that water-rock interaction may contribute to condensation of localized amino acids leading to peptide formation. In order to test this hypothesis, we have developed the Enceladus hydrothermal reactor based on the chemical constraints obtained through previous experimental and theoretical studies. We have added six different amino acids and introduced a thermal fluctuation system simulating the periodic tidal heating of the interior chondritic core. Total, eight sea water samples were obtained over the course of 147 days of experiment. While detection of peptide using Capillary Electrophoresis Time-of-Flight Mass Spectrometry (CE-TOF/MS) is still at the preliminary stage, so far pH monitoring and H2 and CO2 Gas Chromatography Mass Spectrometry (GC-MS) data clearly indicated the occurrence of serpentinization/carbonation reaction. Here, we discuss the interaction between aqueous alteration reactions and thermal cycling processes for the role of abiotic peptide formation under the Enceladus hydrothermal condition.

  4. Acoustic properties of a crack containing magmatic or hydrothermal fluids

    USGS Publications Warehouse

    Kumagai, H.; Chouet, B.A.

    2000-01-01

    We estimate the acoustic properties of a crack containing maginatic or hydrothermal fluids to quantify the source properties of long-period (LP) events observed in volcanic areas assuming that a crack-like structure is the source of LP events. The tails of synthetic waveforms obtained from a model of a fluid-driven crack are analyzed by the Sompi method to determine the complex frequencies of one of the modes of crack resonance over a wide range of the model parameters ??/a and ??f/??s, where ?? is the P wave velocity of the rock matrix, a is the sound speed of the fluid, and ??f and ??s are the densities of the fluid and rock matrix, respectively. The quality factor due to radiation loss (Qr) for the selected mode almost monotonically increases with increasing ??/a, while the dimensionless frequency (??) of the mode decreases with increasing ??/a and ??f/??s. These results are used to estimate Q and ?? for a crack containing various types of fluids (gas-gas mixtures, liquid-gas mixtures, and dusty and misty gases) for values of a, ??f, and quality factor due to intrinsic losses (Qi) appropriate for these types of fluids, in which Q is given by Q-1 = Qr-1 + Qi-1. For a crack containing such fluids, we obtain Q ranging from almost unity to several hundred, which consistently explains the wide variety of quality factors measured in LP events observed at various volcanoes. We underscore the importance of dusty and misty gases containing small-size particles with radii around 1 ??m to explain long-lasting oscillations with Q significantly larger than 100. Our results may provide a basis for the interpretation of spatial and temporal variations in the observed complex frequencies of LP events in terms of fluid compositions beneath volcanoes. Copyright 2000 by the American Geophysical Union.

  5. Potential biomass in deep-sea hydrothermal vent ecosystem

    NASA Astrophysics Data System (ADS)

    Nakamura, K.; Takai, K.

    2012-12-01

    Since the first discovery of black smoker vents hosting chemosynthetic macrofaunal communities (Spiess et al., 1980), submarine hydrothermal systems and associated biota have attracted interest of many researchers (e.g., Humphris et al., 1995; Van Dover, 2000; Wilcock et al., 2004). In the past couple of decades, particular attention has been paid to chemolithoautotrophic microorganisms that sustain the hydrothermal vent-endemic animal communities as the primary producer. This type of microorganisms obtains energy from inorganic substances (e.g., sulfur, hydrogen, and methane) derived from hydrothermal vent fluids, and is often considered as an important modern analogue to the early ecosystems of the Earth as well as the extraterrestrial life in other planets and moons (e.g., Jannasch and Mottl, 1985; Nealson et al., 2005; Takai et al., 2006). Even today, however, the size of this type of chemosynthetic deep-sea hydrothermal vent ecosystem is largely unknown. Here, we present geophysical and geochemical constraints on potential biomass in the deep-sea hydrothermal vent ecosystem. The estimation of the potential biomass in the deep-sea hydrothermal vent ecosystem is based on hydrothermal fluid flux calculated from heat flux (Elderfield and Schltz, 1996), maximum chemical energy available from metabolic reactions during mixing between hydrothermal vent fluids and seawater (McCollom, 2007), and maintenance energy requirements of the chemolithoautotrophic microorganisms (Hoehler, 2004). The result shows that the most of metabolic energy sustaining the deep-sea hydrothermal vent ecosystem is produced by oxidation reaction of reduced sulfur, although some parts of the energy are derived from hydrogenotrophic and methanotrophic reactions. The overall total of the potential biomass in deep-sea hydrothermal vent ecosystem is calculated to be much smaller than that in terrestrial ecosystems including terrestrial plants. The big difference in biomass between the

  6. Impact-generated hydrothermal systems on Earth and Mars

    NASA Astrophysics Data System (ADS)

    Osinski, Gordon R.; Tornabene, Livio L.; Banerjee, Neil R.; Cockell, Charles S.; Flemming, Roberta; Izawa, Matthew R. M.; McCutcheon, Jenine; Parnell, John; Preston, Louisa J.; Pickersgill, Annemarie E.; Pontefract, Alexandra; Sapers, Haley M.; Southam, Gordon

    2013-06-01

    It has long been suggested that hydrothermal systems might have provided habitats for the origin and evolution of early life on Earth, and possibly other planets such as Mars. In this contribution we show that most impact events that result in the formation of complex impact craters (i.e., >2-4 and >5-10 km diameter on Earth and Mars, respectively) are potentially capable of generating a hydrothermal system. Consideration of the impact cratering record on Earth suggests that the presence of an impact crater lake is critical for determining the longevity and size of the hydrothermal system. We show that there are six main locations within and around impact craters on Earth where impact-generated hydrothermal deposits can form: (1) crater-fill impact melt rocks and melt-bearing breccias; (2) interior of central uplifts; (3) outer margin of central uplifts; (4) impact ejecta deposits; (5) crater rim region; and (6) post-impact crater lake sediments. We suggest that these six locations are applicable to Mars as well. Evidence for impact-generated hydrothermal alteration ranges from discrete vugs and veins to pervasive alteration depending on the setting and nature of the system. A variety of hydrothermal minerals have been documented in terrestrial impact structures and these can be grouped into three broad categories: (1) hydrothermally-altered target-rock assemblages; (2) primary hydrothermal minerals precipitated from solutions; and (3) secondary assemblages formed by the alteration of primary hydrothermal minerals. Target lithology and the origin of the hydrothermal fluids strongly influences the hydrothermal mineral assemblages formed in these post-impact hydrothermal systems. There is a growing body of evidence for impact-generated hydrothermal activity on Mars; although further detailed studies using high-resolution imagery and multispectral information are required. Such studies have only been done in detail for a handful of martian craters. The best example so

  7. LIQUID-LIQUID EXTRACTION COLUMNS

    DOEpatents

    Thornton, J.D.

    1957-12-31

    This patent relates to liquid-liquid extraction columns having a means for pulsing the liquid in the column to give it an oscillatory up and down movement, and consists of a packed column, an inlet pipe for the dispersed liquid phase and an outlet pipe for the continuous liquid phase located in the direct communication with the liquid in the lower part of said column, an inlet pipe for the continuous liquid phase and an outlet pipe for the dispersed liquid phase located in direct communication with the liquid in the upper part of said column, a tube having one end communicating with liquid in the lower part of said column and having its upper end located above the level of said outlet pipe for the dispersed phase, and a piston and cylinder connected to the upper end of said tube for applying a pulsating pneumatic pressure to the surface of the liquid in said tube so that said surface rises and falls in said tube.

  8. Active and relict sea-floor hydrothermal mineralization at the TAG hydrothermal field, Mid-Atlantic Ridge

    SciTech Connect

    Rona, P.A. . Atlantic Oceanographic and Meteorological Labs.); Hannington, M.D. ); Raman, C.V. ); Thompson, G.; Tivey, M.K.; Humphris, S.E. ); Lalou, C. . Lab. CNRS-CEA); Petersen, S. Aachen Univ. of Technology )

    1993-12-01

    The TAG hydrothermal field is a site of major active and inactive volcanic-hosted hydrothermal mineralization in the rift valley of the slow-spreading Mid-Atlantic Ridge at 26[degree]N. The axial high is the principal locus of present magmatic intrusions. The TAG field contains three main areas of present and past hydrothermal activity: (1) an actively venting high-temperature sulfide mound; (2) two former high-temperature vent areas; (3) a zone of low-temperature venting and precipitation of Fe and Mn oxide deposits. The volcanic centers occur at the intersections between ridge axis-parallel normal faults and projected axis-transverse transfer faults. The intersections of these active fault systems may act as conduits both for magmatic intrusions from sources beneath the axial high that build the volcanic centers and for hydrothermal upwelling that taps the heat sources. Radiometric dating of sulfide samples and manganese crusts in the hydrothermal zones and dating of sediments intercalated with pillow lava flows in the volcanic center adjacent to the active sulfide mound indicate multiple episodes of hydrothermal activity throughout the field driven by heat supplied by episodic intrusions over a period of at least 140 [times] 10[sup 3] yr. The sulfide deposits are built by juxtaposition and superposition during relatively long residence times near episodic axial heat sources counterbalanced by mass wasting in the tectonically active rift valley of the slow-spreading oceanic ridge. Hydrothermal reworking of a relict hydrothermal zone by high-temperature hydrothermal episodes has recrystallized sulfides and concentrated the first visible primary gold reported in a deposit at an oceanic ridge.

  9. β-Chitin nanofibrils for self-sustaining hydrogels preparation via hydrothermal treatment.

    PubMed

    Nata, Iryanti Fatyasari; Wang, Steven Sheng-Shih; Wu, Tsai-Mao; Lee, Cheng-Kang

    2012-11-01

    A transparent nanofibril suspension could be readily obtained by treating purified squid pen powder in water with ultrasonic irradiation. The obtained suspension is consisted of β-chitin nanofibrils (CNF) with 3-10 nm in width and several micrometers in length. The degree of acetylation (DA) of CNF was found to be 84% which is about 10% lower than that of untreated sample. The CNF suspension could be transformed into a durable 3-D hydrogels (CH) by simply heating to 180 °C for 1-4 h in an autoclave. Hydrophobic interaction between CNF was believed to play the major role for CNF self-assembling into hydrogels, since the as-prepared chitin hydrogels readily dissolved in a typical chaotropic solution (8 M urea) under room temperature. The hydrothermal duration and CNF concentration (0.3-2% (w/v)) strongly affected the physical properties of CH. The suspension of 1% (w/v) CNF treated with 4 h, 180 °C hydrothermal heating generated a CH with 99.3% water content, CNF with 87% crystallinity and an mechanical strength of 0.7 N breaking force.

  10. [Impact of hydrothermal process on the dewaterability and degrease performance of restaurant garbage].

    PubMed

    Ren, Lian-hail; Nie, Yong-feng; Liu, Jian-guo; Jin, Yi-ying

    2006-09-01

    In order to ameliorate the dewaterability and degrease performance of restaurant garbage, and to improve the treatment effect, a complete trail series with 2 factors on 5 levels was implemented. The 2 factors were temperature and retention time respectively as the main influencing factors of hydrothermal process. By means of analyzing the variation of the resistance, dewatering rate and floatable oil content of the treated restaurant garbage, and constructing the solid grease extracting kinetics, the mechanism of impact of hydrothermal process on the dewaterability and degrease performance of restaurant garbage was studied. It showed that the dewaterability of the product decreases at the beginning, after heating for 40min, it begins to increase. Moreover, it increases more quickly as temperature increases. The optimal dewaterability of the treated garbage appears at 180 degrees C and heating for 100 minutes. As temperature rises and heating time increases, the degrease performance is improved. Furthermore, this trend becomes more remarkably as temperature increases. When the temperature and retention time reach 160 degrees C and 80 minutes respectively, most of the solid grease in the garbage is extracted out to become floatable oil which can be separated and recovered readily. Subsequently, the amount of floatable oil begins to decrease since chemical reactions such as the partial hydrolysis of the oil take place. Additionally, the extraction of solid grease from interior accords with first-order reaction dynamic model. PMID:17117654

  11. Understanding the structural features of high-amylose maize starch through hydrothermal treatment.

    PubMed

    Yang, Jianing; Xie, Fengwei; Wen, Wenqiang; Chen, Ling; Shang, Xiaoqin; Liu, Peng

    2016-03-01

    In this study, high-amylose starches were hydrothermally-treated and the structural changes were monitored with time (up to 12h) using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), small-angle X-ray scattering (SAXS), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). When high-amylose starches were treated in boiling water, half-shell-like granules were observed by SEM, which could be due to the first hydrolysis of the granule inner region (CLSM). This initial hydrolysis could also immediately (0.5h) disrupt the semi-crystalline lamellar regularity (SAXS) and dramatically reduce the crystallinity (XRD); but with prolonged time of hydrothermal treatment (≥2 h), might allow the perfection or formation of amylose single helices, resulting in slightly increased crystallinity (XRD and DSC). These results show that the inner region of granules is composed of mainly loosely-packed amylopectin growth rings with semi-crystalline lamellae, which are vulnerable under gelatinization or hydrolysis. In contrast, the periphery is demonstrated to be more compact, possibly composed of amylose and amylopectin helices intertwined with amylose molecules, which require greater energy input (higher temperature) for disintegration.

  12. [Impact of hydrothermal process on the dewaterability and degrease performance of restaurant garbage].

    PubMed

    Ren, Lian-hail; Nie, Yong-feng; Liu, Jian-guo; Jin, Yi-ying

    2006-09-01

    In order to ameliorate the dewaterability and degrease performance of restaurant garbage, and to improve the treatment effect, a complete trail series with 2 factors on 5 levels was implemented. The 2 factors were temperature and retention time respectively as the main influencing factors of hydrothermal process. By means of analyzing the variation of the resistance, dewatering rate and floatable oil content of the treated restaurant garbage, and constructing the solid grease extracting kinetics, the mechanism of impact of hydrothermal process on the dewaterability and degrease performance of restaurant garbage was studied. It showed that the dewaterability of the product decreases at the beginning, after heating for 40min, it begins to increase. Moreover, it increases more quickly as temperature increases. The optimal dewaterability of the treated garbage appears at 180 degrees C and heating for 100 minutes. As temperature rises and heating time increases, the degrease performance is improved. Furthermore, this trend becomes more remarkably as temperature increases. When the temperature and retention time reach 160 degrees C and 80 minutes respectively, most of the solid grease in the garbage is extracted out to become floatable oil which can be separated and recovered readily. Subsequently, the amount of floatable oil begins to decrease since chemical reactions such as the partial hydrolysis of the oil take place. Additionally, the extraction of solid grease from interior accords with first-order reaction dynamic model.

  13. 20 CFR 654.406 - Excreta and liquid waste disposal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 3 2013-04-01 2013-04-01 false Excreta and liquid waste disposal. 654.406... Excreta and liquid waste disposal. (a) Facilities shall be provided and maintained for effective disposal of excreta and liquid waste. Raw or treated liquid waste shall not be discharged or allowed...

  14. 20 CFR 654.406 - Excreta and liquid waste disposal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 false Excreta and liquid waste disposal. 654.406... Excreta and liquid waste disposal. (a) Facilities shall be provided and maintained for effective disposal of excreta and liquid waste. Raw or treated liquid waste shall not be discharged or allowed...

  15. 20 CFR 654.406 - Excreta and liquid waste disposal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false Excreta and liquid waste disposal. 654.406... Excreta and liquid waste disposal. (a) Facilities shall be provided and maintained for effective disposal of excreta and liquid waste. Raw or treated liquid waste shall not be discharged or allowed...

  16. 20 CFR 654.406 - Excreta and liquid waste disposal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Excreta and liquid waste disposal. 654.406... Excreta and liquid waste disposal. (a) Facilities shall be provided and maintained for effective disposal of excreta and liquid waste. Raw or treated liquid waste shall not be discharged or allowed...

  17. 20 CFR 654.406 - Excreta and liquid waste disposal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Excreta and liquid waste disposal. 654.406... Excreta and liquid waste disposal. (a) Facilities shall be provided and maintained for effective disposal of excreta and liquid waste. Raw or treated liquid waste shall not be discharged or allowed...

  18. Hydrothermal Testing of K Basin Sludge and N Reactor Fuel at Sludge Treatment Project Operating Conditions

    SciTech Connect

    Delegard, Calvin H.; Schmidt, Andrew J.; Thornton, Brenda M.

    2007-03-30

    The Sludge Treatment Project (STP), managed for the U. S. DOE by Fluor Hanford (FH), was created to design and operate a process to eliminate uranium metal from K Basin sludge prior to packaging for Waste Isolation Pilot Plant (WIPP). The STP process uses high temperature liquid water to accelerate the reaction, produce uranium dioxide from the uranium metal, and safely discharge the hydrogen. Under nominal process conditions, the sludge will be heated in pressurized water at 185°C for as long as 72 hours to assure the complete reaction (corrosion) of up to 0.25-inch diameter uranium metal pieces. Under contract to FH, the Pacific Northwest National Laboratory (PNNL) conducted bench-scale testing of the STP hydrothermal process in November and December 2006. Five tests (~50 ml each) were conducted in sealed, un-agitated reaction vessels under the hydrothermal conditions (e.g., 7 to 72 h at 185°C) of the STP corrosion process using radioactive sludge samples collected from the K East Basin and particles/coupons of N Reactor fuel also taken from the K Basins. The tests were designed to evaluate and understand the chemical changes that may be occurring and the effects that any changes would have on sludge rheological properties. The tests were not designed to evaluate engineering aspects of the process. The hydrothermal treatment affected the chemical and physical properties of the sludge. In each test, significant uranium compound phase changes were identified, resulting from dehydration and chemical reduction reactions. Physical properties of the sludge were significantly altered from their initial, as-settled sludge values, including, shear strength, settled density, weight percent water, and gas retention.

  19. Enhanced Photocatalytic Performance of ZnS for Reversible Amination of α-oxo Acids by Hydrothermal Treatment

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Li, Qiliang; Liu, Xiaoyang; Yang, Yanqiang; Su, Wenhui

    2012-08-01

    To understand how life could have originated on early Earth, it is essential to know what biomolecules and metabolic pathways are shared by extant organisms and what organic compounds and their chemical reaction channels were likely to have been primordially available during the initial phase of the formation of prebiotic metabolism. In a previous study, we demonstrated for the first time the reversible amination of α-oxo acids on the surface of photo-illuminated ZnS. The sulfide mineral is a typical component at the periphery of submarine hydrothermal vents which has been frequently argued as a very attractive venue for the origin of life. In this work, in order to simulate more closely the precipitation environments of ZnS in the vent systems, we treated newly-precipitated ZnS with hydrothermal conditions and found that its photocatalytic power was significantly enhanced because the relative crystallinity of the treated sample was markedly increased with increasing temperature. Since the reported experimental conditions are believed to have been prevalent in shallow-water hydrothermal vents of early Earth and the reversible amination of α-oxo acids is a key metabolic pathway in all extant life forms, the results of this work provide a prototypical model of the prebiotic amino acid redox metabolism. The amino acid dehydrogenase-like chemistry on photo-irradiated ZnS surfaces may advance our understanding of the establishment of archaic non-enzymatic metabolic systems.

  20. Enhanced photocatalytic performance of ZnS for reversible amination of α-oxo acids by hydrothermal treatment.

    PubMed

    Wang, Wei; Li, Qiliang; Liu, Xiaoyang; Yang, Yanqiang; Su, Wenhui

    2012-08-01

    To understand how life could have originated on early Earth, it is essential to know what biomolecules and metabolic pathways are shared by extant organisms and what organic compounds and their chemical reaction channels were likely to have been primordially available during the initial phase of the formation of prebiotic metabolism. In a previous study, we demonstrated for the first time the reversible amination of α-oxo acids on the surface of photo-illuminated ZnS. The sulfide mineral is a typical component at the periphery of submarine hydrothermal vents which has been frequently argued as a very attractive venue for the origin of life. In this work, in order to simulate more closely the precipitation environments of ZnS in the vent systems, we treated newly-precipitated ZnS with hydrothermal conditions and found that its photocatalytic power was significantly enhanced because the relative crystallinity of the treated sample was markedly increased with increasing temperature. Since the reported experimental conditions are believed to have been prevalent in shallow-water hydrothermal vents of early Earth and the reversible amination of α-oxo acids is a key metabolic pathway in all extant life forms, the results of this work provide a prototypical model of the prebiotic amino acid redox metabolism. The amino acid dehydrogenase-like chemistry on photo-irradiated ZnS surfaces may advance our understanding of the establishment of archaic non-enzymatic metabolic systems.

  1. Ethanol from a biorefinery waste stream: Saccharification of amylase, protease and xylanase treated wheat bran.

    PubMed

    Wood, Ian P; Cook, Nicola M; Wilson, David R; Ryden, Peter; Robertson, James A; Waldron, Keith W

    2016-05-01

    Biorefining aims to exploit the full value of plant material by sequentially extracting and valorising its components. Many studies focus on the saccharification of virgin biomass sources, but it may be more efficient to pre-extract high-value components before hydrolysis to fermentable sugars. In the current study, a bran residue from de-starched, protein depleted and xylanase treated wheat bran has been subjected to hydrothermal pretreatment, saccharification and fermentation procedures to convert the residue to ethanol. The most effective pretreatment conditions (>190 °C, 10 min) and saccharification conditions were identified following bench-scale liquid hot water pretreatment. Pre-extraction of enzymatically-hydrolysable starch and xylan reduced the release of furfural production, particularly when lower pretreatment severities were used. Pilot-scale steam explosion of the lignocellulosic residue followed by cellulase treatment and conversion to ethanol at a high substrate concentration (19%) gave an ethanol titre of ≈ 25 g/L or a yield of 93% of the theoretical maximum. PMID:26769514

  2. Ethanol from a biorefinery waste stream: Saccharification of amylase, protease and xylanase treated wheat bran.

    PubMed

    Wood, Ian P; Cook, Nicola M; Wilson, David R; Ryden, Peter; Robertson, James A; Waldron, Keith W

    2016-05-01

    Biorefining aims to exploit the full value of plant material by sequentially extracting and valorising its components. Many studies focus on the saccharification of virgin biomass sources, but it may be more efficient to pre-extract high-value components before hydrolysis to fermentable sugars. In the current study, a bran residue from de-starched, protein depleted and xylanase treated wheat bran has been subjected to hydrothermal pretreatment, saccharification and fermentation procedures to convert the residue to ethanol. The most effective pretreatment conditions (>190 °C, 10 min) and saccharification conditions were identified following bench-scale liquid hot water pretreatment. Pre-extraction of enzymatically-hydrolysable starch and xylan reduced the release of furfural production, particularly when lower pretreatment severities were used. Pilot-scale steam explosion of the lignocellulosic residue followed by cellulase treatment and conversion to ethanol at a high substrate concentration (19%) gave an ethanol titre of ≈ 25 g/L or a yield of 93% of the theoretical maximum.

  3. Microbiological production and ecological flux of northwestern subduction hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Sunamura, M.; Okamura, K.; Noguchi, T.; Yamamoto, H.; Fukuba, T.; Yanagawa, K.

    2012-12-01

    Deep-sea hydrothermal system is one of the most important sources for heat and chemical flux from the oceanic crust to the global ocean. The rich biological community around the hydrothermal vent shows chemolithoautotrophic microbial production are important in deep sea ecosystems. More than 99% of microbiological available chemical components in hydrothermal vent fluid, e.g. sulfide, methane, hydrogen, Fe2+, and Mn2+, is released into surrounding seawater to construct hydrothermal plume, suggesting that the chemolithoautotrophic-microbial primary production in the hydrothermal plume is huge and important in the whole hydrothermal ecosystems. To understand the impact of hydrothermal plume to a microbial ecosystem and a connectivity with zooplankton, we targeted and investigated a total of 16 hydrothermal fileds (7 sites in Okinawa trough, 3 sites in Ogasawara arc, and 6 sites in Mariana arc and back arc) and investigated in several cruises under the TAIGA project in Japan. Hydrothermal fluids in the subduction system are rich in sulfide. The hydrothermal fluids in the Okinawa trough, Ogasawara arc. and Mariana trough are characterized by rich in methane, poor in other reduced chemicals, and rich in iron, respectively. The major microbial composition was a potential sulfur oxidizing microbes SUP05 in the plume ecosystems, while an aerobic methanotrophic bacteria was secondary major member in methane-rich hydrothermal systems in Okinawa trough. Microbial quantitative and spatial distribution analyses of each plume site showed that the microbial population size and community structures are influenced by original chemical components of hydrothermal fluid, e.g. sulfide, methane and iron concentration. Microbial quantitative data indicated the removal/sedimentation of microbial cells from the plume and effect of phase separation in a same vent field through construction of gas-rich or gas-poor plumes. After the correlation of plume mixing effect, we estimates that the

  4. Direct use of hydrothermal energy: a review of environmental aspects

    SciTech Connect

    O'Banion, K.; Layton, D.

    1981-08-28

    The potential environmental impacts of the exploration, development, and production of hydrothermal geothermal energy for direct use applications are reviewed and evaluated. Mitigation strategies and research and development needs are included. (MHR)

  5. Regional hydrothermal alteration in Noctis Labyrinthus: scattered, yet pervasive

    NASA Astrophysics Data System (ADS)

    Thollot, P.; Mangold, N.; Le Mouélic, S.

    2015-10-01

    We analyzed 113 CRISM cubes in Noctis Labyrinthus. We found 10 classes of alteration minerals including clays and sulfates, sometimes associated in the same setting. Fe and Al sulfates argue for acidic hydrothermal alteration.

  6. Geochemical Energy for Life in Deep-Sea Hydrothermal Systems

    NASA Astrophysics Data System (ADS)

    Amend, J. P.; McCollom, T. M.; Hentscher, M.; Bach, W.

    2010-04-01

    Thermodynamic calculations show that the energetics of both catabolic and anabolic reactions are vastly different in peridotite- and troctolite-hosted hydrothermal systems compared with their basalt- and felsic rock-hosted counterparts.

  7. Process to upgrade coal liquids by extraction prior to hydrodenitrogenation

    DOEpatents

    Schneider, Abraham; Hollstein, Elmer J.; Janoski, Edward J.; Scheibel, Edward G.

    1982-01-01

    Oxygen compounds are removed, e.g., by extraction, from a coal liquid prior to its hydrogenation. As a result, compared to hydrogenation of such a non-treated coal liquid, the rate of nitrogen removal is increased.

  8. Post-drilling hydrothermal vent and associated biological activities seen through artificial hydrothermal vents in the Iheya North field, Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Takai, K.; Kawagucci, S.; Miyazaki, J.; Watsuji, T.; Ishibashi, J.; Yamamoto, H.; Nozaki, T.; Kashiwabara, T.; Shibuya, T.

    2012-12-01

    In 2010, IODP Expedition 331 was conducted in the Iheya North Field, the Okinawa Trough and drilled several sites in hydrothermally active subseafloor. In addition, during the IODP Expedition 331, four new hydrothermal vents were created. These post-drilling artificial hydrothermal vents provide excellent opportunities to investigate the physical, chemical and microbiological characteristics of the previously unexplored subseafloor hydrothermal fluid reservoirs, and to monitor and estimate how the anthropogenic drilling behaviors affect the deep-sea hydrothermal vent ecosystem. We were very much interested in the difference of hydrothermal fluid chemistry between the natural hydrothermal vents and the artificial hydrothermal vents. The IODP porewater chemistry of the cores pointed to the density-driven stratification of the phase-separated hydrothermal fluids and the natural vent fluids were likely derived only from the shallower vapor-enriched phases. However, the artificial hydrothermal vents had deeper fluid sources in the subseafloor hydrothermal fluid reservoirs composed of vapor-lost (Cl-enriched) phases. The fluids from the artificial hydrothermal vents were sampled by ROV at 5, 12 and 18 months after the IODP expedition. The artificial hydrothermal vent fluids were slightly enriched with Cl as compared to the natural hydrothermal vent fluids. Thus, the artificial hydrothermal vents successfully entrained the previously unexplored subseafloor hydrothermal fluids. The newly created hydrothermal vents also hosted the very quickly grown, enormous chimney structures, of which mineral compositions were highly variable among the vents. However, the quickly grown C0016B and C0016D vent chimneys were found to be typical Kuroko ore even though the chimney growth rates in the artificial vents were extremely faster than those in the natural vents. In addition, the IODP drilling operation not only created new hydrothermal vents by deep drilling but also induced the

  9. Hydrothermal fabrication of three-dimensional secondary battery anodes.

    PubMed

    Liu, Jinyun; Zhang, Hui Gang; Wang, Junjie; Cho, Jiung; Pikul, James H; Epstein, Eric S; Huang, Xingjiu; Liu, Jinhuai; King, William P; Braun, Paul V

    2014-11-01

    A generalized hydrothermal strategy for fabricating three-dimensional (3D) battery electrodes is presented. The hydrothermal growth deposits electrochemically active nanomaterials uniformly throughout the complex 3D mesostructure of the scaffold. Ni inverse opals coated with SnO2 nanoparticles or Co3O4 nanoplatelets, and SiO2 inverse opals coated with Fe3O4 are fabricated, all of which show attractive properties including good capacity retention and C-rate performances. PMID:25195592

  10. Chemical environments of submarine hydrothermal systems. [supporting abiogenetic theory

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.

    1992-01-01

    The paper synthesizes diverse information about the inorganic geochemistry of submarine hydrothermal systems, provides a description of the fundamental physical and chemical properties of these systems, and examines the implications of high-temperature, fluid-driven processes for organic synthesis. Emphasis is on a few general features, i.e., pressure, temperature, oxidation states, fluid composition, and mineral alteration, because these features will control whether organic synthesis can occur in hydrothermal systems.

  11. Hydrothermal vents of Yellowstone Lake, Yellowstone National Park, Wyoming

    SciTech Connect

    Kaplinski, M.A.; Morgan, P. . Geology Dept.)

    1993-04-01

    Hydrothermal vent systems within Yellowstone Lake are located within the Yellowstone caldera in the northeastern and West Thumb sections of the lake. The vent systems lie within areas of extremely high geothermal gradients (< 1,000 C/km) in the lake sediments and occur as clusters of individual vents that expel both hydrothermal fluids and gas. Regions surrounding the vents are colonized by unique, chemotropic biologic communities and suggest that hydrothermal input plays an important role in the nutrient dynamics of the lake's ecosystem. The main concentration of hydrothermal activity occurs in the northeast region of the main lake body in a number of locations including: (1) along the shoreline from the southern edge of Sedge Bay to the inlet of Pelican Creek; (2) the central portion of the partially submerged Mary Bay phreatic explosion crater, within deep (30--50 m) fissures; (3) along the top of a 3 km long, steep-sided ridge that extends from the southern border of Mary Bay, south-southeast into the main lake basin; and (4) east of Stevenson Island along the lower portion of the slope (50--107 m) into the lake basin, within an anastomosing series of north to northwest trending, narrow troughs or fissures. Hydrothermal vents were also located within, and surrounding the West Thumb of Yellowstone Lake, with the main concentration occurring the offshore of the West Thumb and Potts Geyser Basin. Hydrothermal vents in Yellowstone Lake occur along fractures that have penetrated the lake sediments or along the tops of ridges and near shore areas. Underneath the lake, rising hydrothermal fluids encounter a semi-permeable cap of lake sediments. Upwardly convecting hydrothermal fluid flow may be diverted by the impermeable lake sediments along the buried, pre-existing topography. These fluids may continue to rise along topography until fractures are encountered, or the lake sediment cover is thinned sufficiently to allow egress of the fluids.

  12. Hydrothermal epitaxy of perovskite thin films

    NASA Astrophysics Data System (ADS)

    Chien, Allen T.

    1998-12-01

    This work details the discovery and study of a new process for the growth of epitaxial single crystal thin films which we call hydrothermal epitaxy. Hydrothermal epitaxy is a low temperature solution route for producing heteroepitaxial thin films through the use of solution chemistry and structurally similar substrates. The application of this synthesis route has led to the growth of a variety of epitaxial perovskite (BaTiOsb3, SrTiOsb3, and Pb(Zr,Ti)Osb3 (PZT)) thin films which provides a simple processing pathway for the formation of other materials of technological interest. BaTiOsb3 and PZT heteroepitaxial thin films and powders were produced by the hydrothermal method at 90-200sp°C using various alkali bases. XRD and TEM analysis shows that, in each case, the films and powders form epitaxially with a composition nearly identical to that of the starting precursors. Sequential growth experiments show that film formation initiates by the nucleation of submicron faceted islands at the step edges of the SrTiOsb3 substrates followed by coalescence after longer growth periods. A Ba-rich interfacial layer between the BaTiOsb3 islands and the SrTiOsb3 surface is seen by cross-section TEM during early growth periods. Electrophoretic and Basp{2+} adsorption data provide a chemical basis for the existence of the interfacial layer. Homoepitaxial growth of SrTiOsb3 on SrTiOsb3 also occurs by island growth, suggesting that the growth mode may be a consequence of the aqueous surface chemistry inherent in the process. Film formation is shown to be affected by any number of factors including type of base, pH, temperature, and substrate pretreatments. Different cation bases (Na-, K-, Rb-, Cs-, TMA-OH) demonstrated pronounced changes in powder and film morphology. For example, smaller cation bases (e.g., NaOH, KOH and RbOH) resulted the formation of 1.5 mum \\{100\\} faceted perovskite PbTiOsb3 blocks while larger cation bases (e.g., CsOH and TMA-OH) produced 500 nm sized

  13. Microbial Community in the Hydrothermal System at Southern Mariana Trough

    NASA Astrophysics Data System (ADS)

    Kato, S.; Itahashi, S.; Kakegawa, T.; Utsumi, M.; Maruyama, A.; Ishibashi, J.; Marumo, K.; Urabe, T.; Yamagishi, A.

    2004-12-01

    There is unique ecosystem around deep-sea hydrothermal area. Living organisms are supported by chemical free energy provided by the hydrothermal water. The ecosystem is expected to be similar to those in early stage of life history on the earth, when photosynthetic organisms have not emerged. In this study, we have analyzed the microbial diversity in the hydrothermal area at southern Mariana trough. In the "Archaean Park Project" supported by special Coordination Fund, four holes were bored and cased by titanium pipes near hydrothermal vents in the southern Mariana trough in 2004. Hydrothermal fluids were collected from these cased holes and natural vents in this area. Microbial cells were collected by filtering the hydrothermal fluid in situ or in the mother sip. Filters were stored at -80C and used for DNA extraction. Chimneys at this area was also collected and stored at -80C. The filters and chimney samples were crushed and DNA was extracted. DNA samples were used for amplification of 16S rDNA fragments by PCR using archaea specific primers and universal primers. The PCR fragments were cloned and sequenced. These PCR clones of different samples will be compared. We will extend our knowledge about microbiological diversity at Southern Mariana trough to compare the results obtained at other area.

  14. Microbial processing of carbon in hydrothermal systems (Invited)

    NASA Astrophysics Data System (ADS)

    LaRowe, D.; Amend, J. P.

    2013-12-01

    Microorganisms are known to be active in hydrothermal systems. They catalyze reactions that consume and produce carbon compounds as a result of their efforts to gain energy, grow and replace biomass. However, the rates of these processes, as well as the size of the active component of microbial populations, are poorly constrained in hydrothermal environments. In order to better characterize biogeochemical processes in these settings, a quantitative relationship between rates of microbial catalysis, energy supply and demand and population size is presented. Within this formulation, rates of biomass change are determined as a function of the proportion of catabolic power that is converted into biomass - either new microorganisms or the replacement of existing cell components - and the amount of energy that is required to synthesize biomass. The constraints that hydrothermal conditions place on power supply and demand are explicitly taken into account. The chemical composition, including the concentrations of organic compounds, of diffuse and focused flow hydrothermal fluids, hydrothermally influenced sediment pore water and fluids from the oceanic lithosphere are used in conjunction with cell count data and the model described above to constrain the rates of microbial processes that influence the carbon cycle in the Juan de Fuca hydrothermal system.

  15. Scientists as stakeholders in conservation of hydrothermal vents.

    PubMed

    Godet, Laurent; Zelnio, Kevin A; VAN Dover, Cindy L

    2011-04-01

    Hydrothermal vents are deep-sea ecosystems that are almost exclusively known and explored by scientists rather than the general public. Continuing scientific discoveries arising from study of hydrothermal vents are concommitant with the increased number of scientific cruises visiting and sampling vent ecosystems. Through a bibliometric analysis, we assessed the scientific value of hydrothermal vents relative to two of the most well-studied marine ecosystems, coral reefs and seagrass beds. Scientific literature on hydrothermal vents is abundant, of high impact, international, and interdisciplinary and is comparable in these regards with literature on coral reefs and seagrass beds. Scientists may affect hydrothermal vents because their activities are intense and spatially and temporally concentrated in these small systems. The potential for undesirable effects from scientific enterprise motivated the creation of a code of conduct for environmentally and scientifically benign use of hydrothermal vents for research. We surveyed scientists worldwide engaged in deep-sea research and found that scientists were aware of the code of conduct and thought it was relevant to conservation, but they did not feel informed or confident about the respect other researchers have for the code. Although this code may serve as a reminder of scientists' environmental responsibilities, conservation of particular vents (e.g., closures to human activity, specific human management) may effectively ensure sustainable use of vent ecosystems for all stakeholders.

  16. Hydrothermal iron flux variability following rapid sea level changes

    NASA Astrophysics Data System (ADS)

    Middleton, Jennifer L.; Langmuir, Charles H.; Mukhopadhyay, Sujoy; McManus, Jerry F.; Mitrovica, Jerry X.

    2016-04-01

    Sea level changes associated with Pleistocene glacial cycles have been hypothesized to modulate melt production and hydrothermal activity at ocean ridges, yet little is known about fluctuations in hydrothermal circulation on time scales longer than a few millennia. We present a high-resolution record of hydrothermal activity over the past 50 ka using elemental flux data from a new sediment core from the Mir zone of the TAG hydrothermal field at 26°N on the Mid-Atlantic Ridge. Mir sediments reveal sixfold to eightfold increases in hydrothermal iron and copper deposition during the Last Glacial Maximum, followed by a rapid decline during the sea level rise associated with deglaciation. Our results, along with previous observations from Pacific and Atlantic spreading centers, indicate that rapid sea level changes influence hydrothermal output on mid-ocean ridges. Thus, climate variability may discretize volcanic processing of the solid Earth on millennial time scales and subsequently stimulate variability in biogeochemical interactions with volcanic systems.

  17. Targeting organic molecules in hydrothermal environments on Mars

    NASA Astrophysics Data System (ADS)

    Parnell, J.; Bowden, S. A.; Lindgren, P.; Wilson, R.; Cooper, J. M.

    2008-09-01

    Hydrothermal deposits on Mars Hydrothermal systems are proposed as environments that could support organic synthesis, the evolution of life or the maintenance of life [1,2,3]. They have therefore been suggested as primary targets for exploration on Mars [1,2,4,].There is now confidence that hydrothermal deposits occur at the martian surface. This is based on a range of criteria that could point towards hydrothermal activity, including volcanic activity, magmatic-driven tectonism, impact cratering in icy terrains, hydrous alteration of minerals and typical hydrothermal mineralogies [4]. The proposals to search for evidence of life at martian hydrothermal sites have been focussed on seeking morphological evidence of microbial activity [5]. Here we discuss the potential to seek a chemical signature of organic matter in hydrothermal systems. Organics in terrestrial hydrothermal systems Terrestrial hydrothermal systems can have large quantities of organic matter because they intersect organic-rich sedimentary rocks or oil reservoirs. Thus the signatures that they contain reflect some preexisting concentration of fossil organic compounds, rather than life which was active in the hydrothermal system. If any extant life was incorporated in these hydrothermal systems, it is swamped by the fossil molecules. Examples of environments where organic materials may become entrained include subsurface hydrothermal mineral deposits, generation of hydrothermal systems by igneous intrusions, and hot fluid venting at the seafloor. Nevertheless, there is value in studying the interactions of hydrothermal systems with fossil organic matter, for information about the survivability of organic compounds, phase relationships between carbonaceous and noncarbonaceous materials, and where in hydrothermal deposits to find evidence of organic matter. Microbial colonization of hot spring systems is feasible at depth within the systems and at the surface where the hydrothermal waters discharge

  18. Topotactic formation of ferrisicklerite from natural triphylite under hydrothermal conditions

    NASA Astrophysics Data System (ADS)

    Schmid-Beurmann, Peter; Ottolini, Luisa; Hatert, Frédéric; Geisler, Thorsten; Huyskens, Magdalena; Kahlenberg, Volker

    2013-08-01

    The topotactic oxidation and delithiation reaction from triphylite, Li(Fe,Mn)PO4, leading to ferrisicklerite, Li<1(Fe3+,Mn2+)PO4, was investigated under hydrothermal conditions. A cuboid cut from a triphylite single-crystal (Palermo Mine, New Hampshire, USA) with the composition Li0.93(3)(Fe2+ 0.733(6),Fe3+ 0.015(1),Mn2+ 0.210(4),Mg0.063(2))1.021(8)P1.00(2)O4 in addition with ground bulk material were treated with KMnO4 and 30 % H2O2(aq) as oxidizing agent in a 0.1 N hydrochloric acid solution in the temperature range between 60 and 200 °C. At 120 °C a rim of 0.1 mm thickness of ferrisicklerite had formed around the core of unreacted triphylite. The sharp reaction boundary was clearly visible, due to the reddish brown absorption colors of ferrisicklerite, compared to colorless triphylite. Using single-crystal X-ray diffraction (XRD), secondary ion mass spectrometry (SIMS), electron probe micro-analysis (EPMA) and 57Fe-Mössbauer spectroscopy the product ferrisicklerite was characterized and its composition determined as Li0.30(7)(Fe2+ 0.049(1)Fe3+ 0.65(2)Mn2+ 0.218(5)Mg0.062(2))0.98(1)P1.01(3)O4, with unit cell parameters a = 4.795(1), b = 9.992(4), and c = 5.886(2) Å. EPMA investigations across the reaction boundary showed no changes in the concentrations of Fe, Mn, Mg, and P. In contrast, SIMS measurements clearly proved the delithiated state of the ferrisicklerite product. Polarization microscopy revealed that the orientation of the ferrisicklerite rim was the same as that of the original triphylite single-crystal, confirming the strictly topotactic character of the reaction.

  19. Lignocellulose Recalcitrance Screening by Integrated High Throughput Hydrothermal Pretreatment and Enzymatic Saccharification

    SciTech Connect

    Selig, M. J.; Tucker, M. P.; Sykes, R. W.; Reichel, K. L.; Brunecky, R.; Himmel, M. E.; Davis, M. F.; Decker, S. R.

    2010-04-01

    We report a novel 96-well multiplate reactor system for comparative analysis of lignocellulose recalcitrance via integrated hydrothermal pretreatment and enzymatic saccharification. The system utilizes stackable nickel/gold-plated 96-well aluminum reactor plates, a clamping device fit to a standard Parr reactor, and robotics for efficient liquids and solids handling. A capacity of 20 plates allows up to 1,920 separate hydrothermal reactions per run. Direct and rapid analysis of key end-products, glucose and xylose, is facilitated by the use of glucose oxidase/peroxidase and xylose dehydrogenase-linked assays. To demonstrate efficacy, a set of 755 poplar core samples from the US Department of Energy's BioEnergy Science Center was tested. Total sugar release ranged from 0.17 to 0.64 g/g of biomass and correlated strongly with the ratio of syringyl to guaiacyl lignins in the samples. Variance among sample replicates was sufficiently minimal to permit clear assignment of differences in recalcitrance throughout this large sample set.

  20. Coupling geophysical investigation with hydrothermal modeling to constrain the enthalpy classification of a potential geothermal resource.

    USGS Publications Warehouse

    White, Jeremy T.; Karakhanian, Arkadi; Connor, Chuck; Connor, Laura; Hughes, Joseph D.; Malservisi, Rocco; Wetmore, Paul

    2015-01-01

    An appreciable challenge in volcanology and geothermal resource development is to understand the relationships between volcanic systems and low-enthalpy geothermal resources. The enthalpy of an undeveloped geothermal resource in the Karckar region of Armenia is investigated by coupling geophysical and hydrothermal modeling. The results of 3-dimensional inversion of gravity data provide key inputs into a hydrothermal circulation model of the system and associated hot springs, which is used to evaluate possible geothermal system configurations. Hydraulic and thermal properties are specified using maximum a priori estimates. Limited constraints provided by temperature data collected from an existing down-gradient borehole indicate that the geothermal system can most likely be classified as low-enthalpy and liquid dominated. We find the heat source for the system is likely cooling quartz monzonite intrusions in the shallow subsurface and that meteoric recharge in the pull-apart basin circulates to depth, rises along basin-bounding faults and discharges at the hot springs. While other combinations of subsurface properties and geothermal system configurations may fit the temperature distribution equally well, we demonstrate that the low-enthalpy system is reasonably explained based largely on interpretation of surface geophysical data and relatively simple models.

  1. TEMPEST: A three-dimensional time-dependent computer program for hydrothermal analysis: Volume 1, Numerical methods and input instructions

    SciTech Connect

    Trent, D.S.; Eyler, L.L.; Budden, M.J.

    1983-09-01

    This document describes the numerical methods, current capabilities, and the use of the TEMPEST (Version L, MOD 2) computer program. TEMPEST is a transient, three-dimensional, hydrothermal computer program that is designed to analyze a broad range of coupled fluid dynamic and heat transfer systems of particular interest to the Fast Breeder Reactor thermal-hydraulic design community. The full three-dimensional, time-dependent equations of motion, continuity, and heat transport are solved for either laminar or turbulent fluid flow, including heat diffusion and generation in both solid and liquid materials. 10 refs., 22 figs., 2 tabs.

  2. Liquid Ventilation

    PubMed Central

    Tawfic, Qutaiba A.; Kausalya, Rajini

    2011-01-01

    Mammals have lungs to breathe air and they have no gills to breath liquids. When the surface tension at the air-liquid interface of the lung increases, as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen, as the inert carrier of oxygen and carbon dioxide offers a number of theoretical advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. The potential for multiple clinical applications for liquid-assisted ventilation will be clarified and optimized in future. PMID:22043370

  3. LIQUID TARGET

    DOEpatents

    Martin, M.D.; Salsig, W.W. Jr.

    1959-01-13

    A liquid handling apparatus is presented for a liquid material which is to be irradiated. The apparatus consists essentially of a reservoir for the liquid, a target element, a drain tank and a drain lock chamber. The target is in the form of a looped tube, the upper end of which is adapted to be disposed in a beam of atomic particles. The lower end of the target tube is in communication with the liquid in the reservoir and a means is provided to continuously circulate the liquid material to be irradiated through the target tube. Means to heat the reservoir tank is provided in the event that a metal is to be used as the target material. The apparatus is provided with suitable valves and shielding to provide maximum safety in operation.

  4. Validation and pharmacokinetic application of a high-performance liquid chromatographic technique for determining the concentrations of amodiaquine and its metabolite in plasma of patients treated with oral fixed-dose amodiaquine-artesunate combination in areas of malaria endemicity.

    PubMed

    Adedeji, Olumuyiwa N; Bolaji, Oluseye O; Falade, Catherine O; Osonuga, Odusoga A; Ademowo, Olusegun G

    2015-09-01

    Artemisinin-based combination therapies (ACTs) have been adopted by most African countries, including Nigeria, as first-line treatments for uncomplicated falciparum malaria. Fixed-dose combinations of these ACTs, amodiaquine-artesunate (FDC AQAS) and artemether-lumefantrine (AL), were introduced in Nigeria to improve compliance and achieve positive outcomes of malaria treatment. In order to achieve clinical success with AQAS, we developed and validated a simple and sensitive high-performance liquid chromatography (HPLC) method with UV detection for determination of amodiaquine (AQ) and desethylamodiaquine (DAQ) in plasma using liquid-liquid extraction of the drugs with diethyl ether following protein precipitation with acetonitrile. Chromatographic separation was achieved using an Agilent Zorbax C18 column and a mobile phase consisting of distilled water-methanol (80:20 [vol/vol]) with 2% (vol/vol) triethylamine, pH 2.2, at a flow rate of 1 ml/min. Calibration curves in spiked plasma were linear from 100 to 1,000 ng/ml (r > 0.99) for both AQ and DAQ. The limit of detection was 1 ng (sample size, 20 μl). The intra- and interday coefficients of variation at 150, 300, and 900 ng/ml ranged from 1.3 to 4.8%, and the biases were between 6.4 and 9.5%. The mean extraction recoveries of AQ and DAQ were 80.0% and 68.9%, respectively. The results for the pharmacokinetic parameters of DAQ following oral administration of FDC AQAS (612/200 mg) for 3 days in female and male patients with uncomplicated falciparum malaria showed that the maximum plasma concentrations (C max) (740 ± 197 versus 767 ± 185 ng/ml), areas under the plasma concentration-time curve (AUC) (185,080 ± 20,813 versus 184,940 ± 16,370 h · ng/ml), and elimination half-life values (T 1/2) (212 ± 1.14 versus 214 ± 0.84 h) were similar (P > 0.05).

  5. Hydrothermal routes to new sodium hydrogen polytungstates.

    PubMed

    Redrup, Kate V; Weller, Mark T

    2009-06-21

    The new acidic sodium polytungstates, Na(5)[H(7)W(12)O(42)].20H(2)O () and Na(2)[H(10)W(12)O(42)].20H(2)O (), have been synthesised under hydrothermal conditions where variations of pH and temperature allow control of the protonation of the [W(12)O(42)](12-) cluster in the products. The polytungstate cluster, [H(n)W(12)O(42)]((12-n)(-)), in each compound consists of the well known polyhedral unit based on 12 edge- and corner-sharing WO(6) octahedra, though the decoration of this unit with varying levels of protons results in significant changes in the W-O distances. The polytungstate clusters exist in arrays separated by sodium ions and water molecules forming well separated, (polytungstate centre to centre distance of 10.87 A), rhombohedrally stacked units in and strongly hydrogen bonded and more tightly packed units, (centre to centre distance of 9.34 A), due to the high H : Na ratio in . PMID:19488444

  6. Catalytic hydrothermal liquefaction of water hyacinth.

    PubMed

    Singh, Rawel; Balagurumurthy, Bhavya; Prakash, Aditya; Bhaskar, Thallada

    2015-02-01

    Thermal and catalytic hydrothermal liquefaction of water hyacinth was performed at temperatures from 250 to 300 °C under various water hyacinth:H2O ratio of 1:3, 1:6 and 1:12. Reactions were also carried out under various residence times (15-60 min) as well as catalytic conditions (KOH and K2CO3). The use of alkaline catalysts significantly increased the bio-oil yield. Maximum bio-oil yield (23 wt%) comprising of bio-oil1 and bio-oil2 as well as conversion (89%) were observed with 1N KOH solution. (1)H NMR and (13)C NMR data showed that both bio-oil1 and bio-oil2 have high aliphatic carbon content. FTIR of bio-residue indicated that the usage of alkaline catalyst resulted in bio-residue samples with lesser oxygen functionality indicating that catalyst has a marked effect on nature of the bio-residue and helps to decompose biomass to a greater extent compared to thermal case. PMID:25240515

  7. Geomicrobiology of Deep-Sea Hydrothermal Vents

    NASA Astrophysics Data System (ADS)

    Jannasch, Holger W.; Mottl, Michael J.

    1985-08-01

    During the cycling of seawater through the earth's crust along the midocean ridge system, geothermal energy is transferred into chemical energy in the form of reduced inorganic compounds. These compounds are derived from the reaction of seawater with crustal rocks at high temperatures and are emitted from warm (<= 25 degrees C) and hot (~ 350 degrees C) submarine vents at depths of 2000 to 3000 meters. Chemolithotrophic bacteria use these reduced chemical species as sources of energy for the reduction of carbon dioxide (assimilation) to organic carbon. These bacteria form the base of the food chain, which permits copious populations of certain specifically adapted invertebrates to grow in the immediate vicinity of the vents. Such highly prolific, although narrowly localized, deep-sea communities are thus maintained primarily by terrestrial rather than by solar energy. Reduced sulfur compounds appear to represent the major electron donors for aerobic microbial metabolism, but methane-, hydrogen-, iron-, and manganese-oxidizing bacteria have also been found. Methanogenic, sulfur-respiring, and extremely thermophilic isolates carry out anaerobic chemosynthesis. Bacteria grow most abundantly in the shallow crust where upwelling hot, reducing hydrothermal fluid mixes with downwelling cold, oxygenated seawater. The predominant production of biomass, however, is the result of symbiotic associations between chemolithotrophic bacteria and certain invertebrates, which have also been found as fossils in Cretaceous sulfide ores of ophiolite deposits.

  8. Cellulose Aggregation under Hydrothermal Pretreatment Conditions.

    PubMed

    Silveira, Rodrigo L; Stoyanov, Stanislav R; Kovalenko, Andriy; Skaf, Munir S

    2016-08-01

    Cellulose, the most abundant biopolymer on Earth, represents a resource for sustainable production of biofuels. Thermochemical treatments make lignocellulosic biomaterials more amenable to depolymerization by exposing cellulose microfibrils to enzymatic or chemical attacks. In such treatments, the solvent plays fundamental roles in biomass modification, but the molecular events underlying these changes are still poorly understood. Here, the 3D-RISM-KH molecular theory of solvation has been employed to analyze the role of water in cellulose aggregation under different thermodynamic conditions. The results show that, under ambient conditions, highly structured hydration shells around cellulose create repulsive forces that protect cellulose microfibrils from aggregating. Under hydrothermal pretreatment conditions, however, the hydration shells lose structure, and cellulose aggregation is favored. These effects are largely due to a decrease in cellulose-water interactions relative to those at ambient conditions, so that cellulose-cellulose attractive interactions become prevalent. Our results provide an explanation to the observed increase in the lateral size of cellulose crystallites when biomass is subject to pretreatments and deepen the current understanding of the mechanisms of biomass modification. PMID:27301535

  9. Reconnaissance of the hydrothermal resources of Utah

    SciTech Connect

    Rush, F.E.

    1983-01-01

    Geologic factors in the Basin and Range province in Utah are more favorable for the occurrence of geothermal resources than in other areas on the Colorado Plateaus or in the Middle Rocky Mountains. These geologic factors are principally crustal extension and crustal thinning during the last 17 million years. Basalts as young as 10,000 years have been mapped in the area. High-silica volcanic and intrusive rocks of Quaternary age can be used to locate hydrothermal convection systems. Drilling for hot, high-silica, buried rock bodies is most promising in the areas of recent volcanic activity. Southwestern Utah has more geothermal potential than other parts of the Basin and Range province in Utah. The Roosevelt Hot Springs area, the Cove Fort-Sulphurdale area, and the area to the north as far as 60 kilometers from them probably have the best potential for geothermal development for generation of electricity. Other areas with estimated reservoir temperatures greater than 150/sup 0/C are Thermo, Monroe, Red Hill (in the Monroe-Joseph Known Geothermal Resource Area), Joseph Hot Springs, and the Newcastle area. The rates of heat and water discharge are high at Crater, Meadow, and Hatton Hot Springs, but estimated reservoir temperatures there are less than 150/sup 0/C. Additional exploration is needed to define the potential in three additional areas in the Escalante Desert. 28 figs., 18 tabs.

  10. Catalytic hydrothermal liquefaction of water hyacinth.

    PubMed

    Singh, Rawel; Balagurumurthy, Bhavya; Prakash, Aditya; Bhaskar, Thallada

    2015-02-01

    Thermal and catalytic hydrothermal liquefaction of water hyacinth was performed at temperatures from 250 to 300 °C under various water hyacinth:H2O ratio of 1:3, 1:6 and 1:12. Reactions were also carried out under various residence times (15-60 min) as well as catalytic conditions (KOH and K2CO3). The use of alkaline catalysts significantly increased the bio-oil yield. Maximum bio-oil yield (23 wt%) comprising of bio-oil1 and bio-oil2 as well as conversion (89%) were observed with 1N KOH solution. (1)H NMR and (13)C NMR data showed that both bio-oil1 and bio-oil2 have high aliphatic carbon content. FTIR of bio-residue indicated that the usage of alkaline catalyst resulted in bio-residue samples with lesser oxygen functionality indicating that catalyst has a marked effect on nature of the bio-residue and helps to decompose biomass to a greater extent compared to thermal case.

  11. Geomicrobiology of deep-sea hydrothermal vents.

    PubMed

    Jannasch, H W; Mottl, M J

    1985-08-23

    During the cycling of seawater through the earth's crust along the mid-ocean ridge system, geothermal energy is transferred into chemical energy in the form of reduced inorganic compounds. These compounds are derived from the reaction of seawater with crustal rocks at high temperatures and are emitted from warm (hydrothermal fluid mixes with downwelling cold, oxygenated seawater. The predominant production of biomass, however, is the result of symbiotic associations between chemolithotrophic bacteria and certain invertebrates, which have also been found as fossils in Cretaceous sulfide ores of ophiolite deposits.

  12. Frictional slip of granite at hydrothermal conditions

    USGS Publications Warehouse

    Blanpied, M.L.; Lockner, D.A.; Byerlee, J.D.

    1995-01-01

    To measure the strength, sliding behavior, and friction constitutive properties of faults at hydrothermal conditions, laboratory granite faults containing a layer of granite powder (simulated gouge) were slid. The mechanical results define two regimes. The first regime includes dry granite up to at least 845?? and wet granite below 250??C. In this regime the coefficient of friction is high (?? = 0.7 to 0.8) and depends only modestly on temperature, slip rate, and PH2O. The second regime includes wet granite above ~350??C. In this regime friction decreases considerably with increasing temperature (temperature weakening) and with decreasing slip rate (velocity strengthening). These regimes correspond well to those identified in sliding tests on ultrafine quartz. The results highlight the importance of fluid-assisted deformation processes active in faults at depth and the need for laboratory studies on the roles of additional factors such as fluid chemistry, large displacements, higher concentrations of phyllosilicates, and time-dependent fault healing. -from Authors

  13. Hydrothermal Gasification for Waste to Energy

    NASA Astrophysics Data System (ADS)

    Epps, Brenden; Laser, Mark; Choo, Yeunun

    2014-11-01

    Hydrothermal gasification is a promising technology for harvesting energy from waste streams. Applications range from straightforward waste-to-energy conversion (e.g. municipal waste processing, industrial waste processing), to water purification (e.g. oil spill cleanup, wastewater treatment), to biofuel energy systems (e.g. using algae as feedstock). Products of the gasification process are electricity, bottled syngas (H2 + CO), sequestered CO2, clean water, and inorganic solids; further chemical reactions can be used to create biofuels such as ethanol and biodiesel. We present a comparison of gasification system architectures, focusing on efficiency and economic performance metrics. Various system architectures are modeled computationally, using a model developed by the coauthors. The physical model tracks the mass of each chemical species, as well as energy conversions and transfers throughout the gasification process. The generic system model includes the feedstock, gasification reactor, heat recovery system, pressure reducing mechanical expanders, and electricity generation system. Sensitivity analysis of system performance to various process parameters is presented. A discussion of the key technological barriers and necessary innovations is also presented.

  14. The hydrothermal system at Newberry Volcano, Oregon

    USGS Publications Warehouse

    Sammel, E.A.; Ingebritsen, S.E.; Mariner, R.H.

    1988-01-01

    Results of recent geological and geophysical studies at Newberry Volcano have been incorporated into conceptual and numerical models of a magma-based hydrothermal system. Numerical simulations begin with emplacement of a small magma body, the presumed source of silicic eruptions at Newberry that began about 10 000 BP, into a thermal regime representing 100 000 yr of cooling of a large underlying intrusion. Simulated flow patterns and thermal histories for three sets of hypothetical permeability values are compatible with data from four geothermal drill holes on the volcano. Meteoric recharge cools the caldera-fill deposits, but thermal water moving up a central conduit representing a permeable volcanic vent produces temperatures close to those observed in drill holes within the caldera. Meteoric recharge from the caldera moves down the flanks and creates a near-isothermal zone that extends several hundred meters below the water table, producing temperature profiles similar to those obserbed in drill holes on the flanks. The temperatures observed in drillholes on the flanks are not influenced by the postulated Holocene magma body. The elevated temperature gradients measured in the lower portions of these holes may be related to the cumulative effect of older intrusions. The models also indicate that meteoric recharge to the deep hyrothermal system probably originates within or near the caldera. Relatively low fluid velocities at depth suggest that at least a significant fraction of the thermal fluid may be very old. -Authors

  15. Hydrothermal Vents in Yellowstone Lake: Chemical Fluxes, Siliceous Deposits, and Collapse Structures

    NASA Astrophysics Data System (ADS)

    Shanks, W. P.; Morgan, L. A.; Balistrieri, L.; Alt, J.; Meeker, G.

    2002-12-01

    The geochemistry of Yellowstone Lake is strongly influenced by sublacustrine hydrothermal vent activity. The hydrothermal source fluid is identified using Cl and dD data on water column and sublacustrine hydrothermal vent fluid samples. Silica-rich hydrothermal deposits occur on the lake bottom near active and presently inactive hydrothermal vents. Pipe- and flange-like deposits contain cemented and recrystallized diatoms and represent pathways for hydrothermal fluid migration. Another major type of hydrothermal deposit comprises hard, porous siliceous spires up to 7 m tall that occur in 15 m of water in Bridge Bay. Bridge Bay spires are hydrothermal silica deposits formed in place by growth of chimney-like features from lake-bottom hydrothermal vents. The Cl concentrations indicate that Yellowstone Lake water is about 1 percent hydrothermal source fluid and 99 percent inflowing stream water and that the flux is about 10 percent of the total hydrothermal water flux in Yellowstone National Park. With recent swath-sonar mapping studies that show numerous new hydrothermal features, Yellowstone Lake should now be considered one of the most significant hydrothermal basins in the Park. Many lake-bottom hydrothermal vents occur in small depressions that are clearly imaged on multibeam sonar, some of which are interpreted as collapse structures based on seismic reflection data. Sediments collected from such vents show chemical evidence of leaching of 60-70 wt. percent SiO2, which may result in volume reductions up to 80 percent and provides a mechanism for vent structure formation.

  16. Sub-glacial Origin of the Hot Springs Bay Valley hydrothermal System, Akutan, Alaska

    NASA Astrophysics Data System (ADS)

    Stelling, P. L.; Tobin, B.; Knapp, P.

    2015-12-01

    Exploration for geothermal energy in Hot Springs Bay Valley (HSBV) on Akutan Island, Alaska, has revealed a rich hydrothermal history, including what appears to be a stage of peak activity during a significant glacial period. Alteration mineralogy observed in 754 m of drill core recovered from the outflow zone is dominated by chlorite and includes minor smectite clays, a suite of zeolite species and several moderately high-temperature hydrothermal minerals (epidote/clinozoisite, prehnite, adularia and wairakite). The latter minerals each have minimum formation temperatures exceeding 200 oC, and fluid inclusion results in related calcite crystals indicate temperatures of formation to be as high as 275 oC, some 100 oC hotter than the modern boiling point with depth (BPD) curve at that depth (>62 m). In order to maintain liquid temperatures this high, the pressure during mineralization must have been substantially greater (~680 bar), a pressure change equivalent to erosion of ~280 m of rock (ρ=2.5 g/cm3). Although glacial erosion rates are too low (0.034 mm/yr; Bekele et al., 2003) for this amount of erosion to occur in a single glaciation, glacial melting and ablation are substantially more rapid (~100 mm/yr; Bekele et al., 2003; Person et al., 2012). Thus, a more probable scenario than pure erosion is that peak hydrothermal conditions occurred during a large glacial event, with the added pressure from the overlying ice allowing the high temperature minerals to form closer to the ground surface. Subsequent melting of the ice eroded upper tributary valleys and upper levels of the originally smectite-rich alteration assemblage, explaining the paucity of swelling clays in the region. We present mineralogical, fluid inclusion and geochronologic evidence to support these conclusions, and discuss the general implications of sub-glacial hydrothermal system formation and geothermal resource potential. References: Bekele, E., Rostron, B. and Person, M. (2003) Fluid pressure

  17. Hydrothermal synthesis of hydrocarbons at low temperature. Implications for sustaining a biosphere in Europa

    NASA Astrophysics Data System (ADS)

    Navarro-Gonzalez, Rafael; Montoya, Lilia; Davis, Wanda; McKay, Chris

    Observational evidence from Earth-borne systems and space missions as well as theoretical arguments suggest that Jupiter's satellite Europa could be geologically active today and may possess an ocean of liquid water of about 100 km deep underneath the icy surface about 10 km thickness. The existence of an aqueous ocean is an important requirement for life, as we know it. However, a biosphere also depends of an adequate energy source to drive the most fundamental biological processes such as metabolism, growth, reproduction, etc. Methanogenesis associated with hydrothermal vents may potentially drive a biosphere in an European ocean. We report here on the production of a large variety of hydrocarbons in hydrothermal systems at low temperatures (150° C). The chemical composition of the hydrothermal vent gases was derived from a thermochemical model that assumes that Europa had a cometary (solar, less H) abundance at high temperatures characteristic of a vent. Specifically the following gas mixture was used: 45% CO2 , 45% CH4, and 10 % N2 . A 500 ml stainless steel reactor was filled with 200 ml triply distilled water and the gas mixture at 1 bar at 25° C. In some experiments 3 g of pyrite were added into the reaction vessel. The system was heated for 24 hrs in the temperature range from 100 to 375° C. At the completion of the experiment, the reaction was quenched to 25° C and the gas mixture was analyzed by GC-FTIR-MS techniques. In the absence of pyrite, methane is oxidized to carbon dioxide with the possible production of hydrogen. In contrast in the presence of pyrite, methane is converted into a suite of hydrocarbons from C2 to C7 containing all possible isomers. The production of these compounds was found at temperatures as low as 150° C. In order to get a better understanding of the chemical mechanism involved in the synthesis of hydrocarbons and explore the effect on the initial oxidation state of the carbon used, we performed additional experiments in

  18. Evaluation of a new liquid occlusive dressing for excisional wounds.

    PubMed

    Singer, Adam J; Nable, Maria; Cameau, Paul; Singer, Daniel D; McClain, Steve A

    2003-01-01

    We evaluated a novel octylcyanoacrylate-based liquid occlusive dressing for partial-thickness wounds. One hundred and fifteen standardized wounds were created with an electric dermatome set at a depth of 600 micro on the flanks of three pigs and randomly treated with liquid occlusive dressing, a hydrocolloid dressing, or gauze. In one pig, wounds were swabbed with Staphylococcus aureus. Biopsies were taken after 4, 5, 6, and 21 days. Hemostasis was obtained in all wounds treated with the liquid occlusive. The percent reepithelialization of wounds treated with the liquid occlusive and hydrocolloid dressings were significantly greater at days 4 and 5 than control wounds (78% and 82% vs. 40%, p < 0.001 and 99% and 100% vs. 72%, p < 0.001, respectively). None of the liquid occlusive-treated wounds challenged with bacteria became infected. Foreign body reactions were least common in wounds treated with the liquid occlusive (p < 0.001). Scar depth was less for liquid occlusive- and hydrocolloid-treated wounds than controls (285 micro and 303 micro vs. 490 micro, p < 0.001). We conclude that excisional wounds treated with the liquid occlusive dressing reepithelialize as quickly as hydrocolloid-treated wounds. The liquid occlusive dressing is an effective microbial barrier and hemostatic agent resulting in fewer foreign body reactions than hydrocolloid-treated wounds or controls.

  19. The use of air as a natural tracer infractured hydrothermal systems, Los Azufres, Mexico, case study

    SciTech Connect

    Mario Cesar Sudrez Arriaga; Hector Gutierrez Puente, Josefina Moreno Ochoa

    1991-01-01

    Injection of atmospheric air mixed with cold water has been occurring since 1982 at the Los Azufres geothermal field. Several chemical and thermodynamical evidences show that air injection into this fractured hydrothermal system could be considered as a long term natural tracer test. Nitrogen and Argon separated from the air mixture migrate, under the action of the induced injection-extraction gradient, from reinjection sectors to production zones following preferential paths closely related to high permeability conduits. A coarse numerical estimation of the average permeability tensor existing at Tejamaniles, the southern sector, explains the unsuccessful recovery of the artificial tracer tests performed in past years: the anisotropic nature of the fractured volcanic rock would demand considerably quantities of tracer in order to be detected at the producing wells, especially when fluid extraction was low. At the same time concentrations of calcium, cesium, chloride, potassium, rubidium and sodium, are increasing in the liquid produced by the oldest wells of this field's sector.

  20. Hydrothermal carbonization of off-specification compost: a byproduct of the organic municipal solid waste treatment.

    PubMed

    Basso, Daniele; Weiss-Hortala, Elsa; Patuzzi, Francesco; Castello, Daniele; Baratieri, Marco; Fiori, Luca

    2015-04-01

    The possibility to apply the hydrothermal carbonization (HTC) process to off-specification compost (EWC 19.05.03) at present landfilled was investigated in this work. The aim was to produce a carbonaceous solid fuel for energy valorization, with the perspective of using HTC as a complementary technology to common organic waste treatments. Thus, samples of EWC 19.05.03 produced by a composting plant were processed through HTC in a batch reactor. Analytical activities allowed to characterize the HTC products and their yields. The hydrochar was characterized in terms of heating value, thermal stability and C, H, O, N, S and ash content. The liquid phase was characterized in terms of total organic carbon and mineral content. The composition of the gas phase was measured. Results show that the produced hydrochar has a great potentiality for use as solid fuel.

  1. Green hydrothermal synthesis and optical properties of γ-Gd2S3 nanoparticles

    NASA Astrophysics Data System (ADS)

    Khajuria, Sonika; Ladol, Jigmet; Sanotra, Sumit; Sheikh, Haq Nawaz

    2016-06-01

    Green synthesis of γ-Gd2S3 nanoparticles was carried out using low-temperature hydrothermal route in autoclave. A 1:1 mixture of ionic liquid 1-ethyl-3-methylimidazolium ethyl sulfate, ([EMIM][EtSO4]), and water was used as a solvent. Synthesized nanoparticles were characterized by x-ray powder diffraction (XRPD), scanning electron microscopy (SEM), UV-visible spectroscopy (UV-vis), particle size by dynamic light scattering (DLS) technique, and photoluminescence (PL) studies. XRPD suggests cubic Th3P4-type structure for obtained Gd2S3 nanoparticles. The size of synthesized nanoparticles is about 86 nm. Optical band gap for these nanoparticles estimated from electronic spectrum is 2.95 eV which shows blue shift from values reported for bulk Gd2S3 due to pronounced quantum mechanical effect. These nanoparticles show sharp emission peak at 385 nm and a broad shoulder at 475 nm when excited at 260 nm.

  2. Phases' characteristics of poultry litter hydrothermal carbonization under a range of process parameters.

    PubMed

    Mau, Vivian; Quance, Julie; Posmanik, Roy; Gross, Amit

    2016-11-01

    The aim of this work was to study the hydrothermal carbonization of poultry litter under a range of process parameters. Experiments were conducted to investigate the effect of HTC of poultry litter under a range of operational parameters (temperature, reaction time, and solids concentration) on the formation and characteristics of its phases. Results showed production of a hydrochar with caloric value of 24.4MJ/kg, similar to sub-bituminous coal. The gaseous phase consisted mainly of CO2. However, significant amounts of H2S dictate the need for (further) treatment. The process also produced an aqueous phase with chemical characteristics suggesting its possible use as a liquid fertilizer. Temperature had the most significant effect on processes and product formation. Solids concentration was not a significant factor once dilution effects were considered. PMID:27544913

  3. Hydrothermal carbonization of sugarcane bagasse via wet torrefaction in association with microwave heating.

    PubMed

    Chen, Wei-Hsin; Ye, Song-Ching; Sheen, Herng-Kuang

    2012-08-01

    Hydrothermal carbonization of sugarcane bagasse using wet torrefaction is studied. The biomass is torrefied in water or dilute sulfuric acid solution and microwaves are employed to heat the solutions where the reaction temperature is fixed at 180 °C. The effects of acid concentration, heating time and solid-to-liquid ratio on the performance of wet torrefaction are investigated. It is found that the addition of sulfuric acid and increasing heating time are conducive to carbonizing bagasse. The calorific value of bagasse can be increased up to 20.3% from wet torrefaction. With the same improvement in calorific value, the temperature of wet torrefaction is lower than that of dry torrefaction around 100 °C, revealing that wet torrefaction is a promising method to upgrade biomass as fuel. The calorific value of torrefied biomass can be predicted well based on proximate, elemental or fiber analysis, and the last one gives the best estimation.

  4. Evaluating the Historical Importance of Impact Induced Hydrothermal Systems on Mars Using the Stable Isotopic Composition of Martian Water

    NASA Technical Reports Server (NTRS)

    Niles, Paul B.

    2010-01-01

    The importance of impact events during the early history of Mars is obvious through a simple examination of the character of the martian surface. This ancient, heavily cratered terrain has been shown to be associated with extensive phyllosilicate deposits. This geologic link could suggest that the extensive phyllosilicate-forming alteration may have occurred during early martian history through impact-induced hydrothermal alteration. However, examination of the oxygen isotopic composition of water on Mars suggests that the extensive phyllosilicate deposits were formed primarily through low temperature (<30 C) interactions, and that high temperature weathering in impact-induced hydrothermal systems have not been a dominant process on Mars. The average oxygen isotopic composition of water on Earth is dictated by the nature of water-rock interactions. If these interactions occur at higher temperatures then the water will contain a higher proportion of 18O, while lower temperature interactions will result in water with a lower proportion of 18O. Water on Earth today contains a higher proportion of 18O because of plate tectonics and hydrothermal interaction at mid-ocean ridges. The oxygen isotopic composition of water on early earth, however, may have been quite different, containing a smaller proportion of 18O suggesting much less hydrothermal interaction. Because there are not yet any direct measurements of the oxygen isotopic composition of water on Mars, it needs to be inferred through examination of carbonates preserved in martian meteorites and the isotopic composition of atmospheric CO2. This can be done because the oxygen incorporated into carbonates and CO2 is easily exchanged with liquid water if it is present. Independently, both measurements provide an estimate for the (Sigma)18O of water on Mars to be near -16%. This composition is consistent with low temperature weathering of the silicate crust, and indicates that impact hydrothermal systems did not play

  5. Effects of hydrothermal pretreatment of sugar beet pulp for methane production.

    PubMed

    Ziemiński, K; Romanowska, I; Kowalska-Wentel, M; Cyran, M

    2014-08-01

    The effect of Liquid Hot Water treatment conditions on the degree of sugar beet pulp (SBP) degradation was studied. The SBP was subjected to hydrothermal processing at temperatures ranging from 120 to 200 °C. The relationship between processing temperature and parameters of liquid and solid fractions of resulting hydrolysates as well as the efficiency of their methane fermentation was determined. The highest concentration of free glucose (3.29 mg ml(-1)) was observed when the hydrolysis was conducted at 160 °C (it was 4-fold higher than that after processing at 120 °C). Total acids and aldehydes concentrations in the liquid fractions were increased from 0.005 mg ml(-1) for the untreated SBP to 1.61 mg ml(-1) after its processing at 200 °C. Parameters of the hydrolysates obtained by the LHW treatment decided of the efficiency of methane fermentation. The highest cumulative methane yield (502.50 L CH₄ kg(-1)VS) was obtained from the sugar beet pulp hydrolysate produced at 160 °C.

  6. Impact Crater Hydrothermal Niches for Life on Mars: Question of Scale

    NASA Technical Reports Server (NTRS)

    Pope, K. O.; Ames, D. E.; Kieffer, S. W.; Ocampo, A. C.

    2000-01-01

    A major focus in the search for fossil life on Mars is on ancient hydrothermal deposits. Nevertheless, remote sensing efforts have not found mineral assemblages characteristic of hydrothermal activity. Future remote sensing work, including missions with higher spatial resolution, may detect localized hydrothermal deposits, but it is possible that dust mantles will prohibit detection from orbit and lander missions will be required. In anticipation of such missions, it is critical to develop a strategy for selecting potential hydrothermal sites on Mars. Such a strategy is being developed for volcanogenic hydrothermal systems, and a similar strategy is needed for impact hydrothermal systems.

  7. Hydrothermal zeolitisation controlled by host-rock lithofacies in the Periadriatic (Oligocene) Smrekovec submarine composite stratovolcano, Slovenia

    NASA Astrophysics Data System (ADS)

    Kralj, Polona

    2016-05-01

    Hydrothermal zeolites (laumontite, yugawaralite, analcime, heulandite, clinoptilolite), prehnite and pumpellyite have been recognised in a succession of volcanic, autoclastic, pyroclastic, resedimented volcaniclastic and mixed siliciclastic-volcaniclastic deposits. In cone-building lithofacies association attaining 310 m, the alteration minerals commonly change within a single normally graded depositional unit or alternate in the section on a dm- to m-scale, according to the host-rock lithofacies. Fine-grained deposits rich in juvenile glassy pyroclasts are altered to heulandite and clinoptilolite or analcime, and laumontite widely occurs in coarse-grained host-rocks (lapilli tuff, hyaloclastite breccia, volcaniclastic breccia, hyaloclastites) and fracture systems. In near-vent lithofacies association attaining 420 m, prehnite-laumontite, laumontite-analcime, and laumontite-heulandite-clinoptilolite zones developed as a result of superimposed thermal regime generated by the emplacement of an over 200 m thick sill. The recognised dependence of alteration on porosity, permeability and fracturing of the host-rock is closely related to hydrological conditions in the stratovolcano-hosted hydrothermal system with convective-advective flow regime. After separation of steam and gases from convecting hydrothermal fluids, denser liquids outflowed intermittently, preferentially through steeply inclined (20-30°) high-permeability layers in the stratovolcano edifice. In low-permeability layers the flow was slow and thermal conditions were mainly attained by conduction. Zeolites developed only in coarse- and fine-grained vitroclastic tuffs, presumably by the dissolution of volcanic glass. The interstratified siliciclastic siltstones, tuffites and resedimented deposits with low content of glassy particles are devoid of zeolites and indicate compositional constraint on zeolitisation. Lava flows, cooling in a submarine environment and undergoing disintegration and mingling with

  8. Fluid inclusion evidence for hydrothermal fluid evolution in the Darreh-Zar porphyry copper deposit, Iran

    NASA Astrophysics Data System (ADS)

    Nateghi, Arash; Hezarkhani, Ardeshir

    2013-09-01

    The Darreh-Zar porphyry copper deposit is associated with a quartz monzonitic-granodioritic-porphyritic stock hosted by an Eocene volcanic sedimentary complex in which magmatic hydrothermal fluids were introduced and formed veins and alteration. Within the deepest quartz-rich and chalcopyrite-poor group A veins, LVHS2 inclusions trapped high salinity, high temperature aqueous fluids exsolved directly from a relatively shallow magma (0.5 kbar). These late fluids were enriched in NaCl and reached halite saturation as a result of the low pressure of magma crystallization and fluid exsolution. These fluids extracted Cu from the crystallizing melt and transported it to the hydrothermal system. As a result of ascent, the temperature and pressure of these fluids decreased from 600 to 415 °C, and approximately 500-315 bars. At these conditions, K-feldspar and biotite were stabilized. Type A veins were formed at a depth of ∼1.2 km under conditions of lithostatic pressure and abrupt cooling. Upon cooling and decompressing, the fluid intersected with the liquid-vapor field resulting in separation of immiscible liquid and vapor. This stage was recorded by formation of LVHS1, LVHS3 and VL inclusions. These immiscible fluids formed chalcopyrite-pyrite-quartz veins with sericitic alteration envelopes (B veins) under the lithostatic-hydrostatic pressure regime at temperatures between 415 and 355 °C at 1.3 km below the paleowater table. As the fluids ascended, copper contents decreased and these fluids were diluted by mixing with the low salinity-external fluid. Therefore, pyrite-dominated quartz veins were formed in purely hydrostatic conditions in which pressure decreased from 125 bars to 54 bars and temperature decreased from 355 to 298 °C. During the magmatic-hydrothermal evolution, the composition and P-T regime changed drastically and caused various types of veins and alterations. The abundance of chalcopyrite precipitation in group B veins suggests that boiling and

  9. Geophysical Constraints On Enceladus' Hydrothermal Activity

    NASA Astrophysics Data System (ADS)

    Matson, D.; Castillo, J. C.; Johnson, T. V.; Lunine, J. I.; Davies, A. G.

    2011-12-01

    Cassini-Huygens discovered many eruptive plumes and a heat flow of about 15 GW [1] in the South Polar Region of Enceladus. The plume material is believed to come from an ocean [2]. We have modeled the heat and chemicals as coming to the surface via the circulation of relatively warm ocean water [3]. The major challenge for our work is to explain how circulation of water can be maintained in the very cold crust. The upper boundary condition is relatively simple. Where seawater contacts surface ice the temperature is ~-2 C. Also, under the right conditions, tidally induced fissures in the surface ice can fill with water that freezes, producing new ice. The lower boundary temperature is difficult to characterize precisely. The ocean is several degrees warmer than the ice. Consequently there will be some melting at the bottom of the crust. The melt water is less dense than seawater and floats on it. As a result, an ice-ocean interface layer is formed. This layer is stable against Rayleigh-Bénard convection. The layer regulates the rate at which heat is transferred and the temperature at which melt water is produced through temperature and salinity gradients. Currents in the ocean below and other variables influence the extent and shape of the interface layer. A somewhat similar interface layer (thermal gradient only) has been discussed and modeled for Europa [4] and many of those considerations apply to Enceladus. In the Europa case a layer thickness of ~200 m was suggested and that should be roughly what one might also expect for Enceladus. We demonstrate that it is feasible to keep this hydrothermal activity going over the long-term, as long as it is powered by a deep source of heat whose origin is still to be determined. This work was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2011 Caltech.

  10. Hydrothermal calcite in the Elephant Moraine

    SciTech Connect

    Faure, G.; Taylor, K.S.; Jones, L.M.

    1986-01-01

    In the course of geologic mapping of the Elephant Moraine on the east antarctic ice sheet, Faure and Taylor (1985) collected several specimens of black botryoidal calcite, composed of radiating acicular crystals that resemble stromatolites. Calcite from this and other specimens is significantly enriched in strontium-87 (the strontium-87/strontium-86 ratio equals 0.71417 +/- 0.00002), carbon-12 (delta carbon-13 equals -22.9 parts per thousand, PDB standard) and oxygen-16 (delta oxygen-18 equals -21.1 parts per thousand, standard mean ocean water) compared with calcite of marine origin. The enrichment in carbon-12 is similar to that of calcite associated with coal in the Allan Hills. The enrichment in oxygen-16 indicates that the calcite from the Elephant Moraine could only have precipitated in isotopic equilibrium with glacial melt water. Therefore, the temperature at which the black calcite precipitated from water of that isotope composition was about 85/sup 0/C. A temperature of this magnitude implies that the black calcite formed as a result of volcanic activity under the east antarctic ice sheet. The enrichment of the black calcite in carbon-12 suggests that it formed in part from carbon dioxide derived from the coal seams of the Weller Formation in the Beacon Supergroup. The isotopic composition of strontium in the black calcite is similar to that of carbonate beds and concretions in the Beacon rocks of southern Victoria Land. A volcanic-hydrothermal origin is also consistent with the very low total organic carbon content of 0.15% in the calcite.

  11. Hydrothermal synthesis of pyrochlores and their characterization

    NASA Astrophysics Data System (ADS)

    Redkin, Alexander F.; Ionov, Andrey M.; Kotova, Nataliya P.

    2013-10-01

    Pyrochlores, microlites, and U-betafites of pyrochlore group minerals were obtained from mixing experiments of the corresponding oxides and fluorides by hydrothermal synthesis at T = 800 °C and P = 200 MPa in the solution of 1.0 M NaF. The presence of U4+ in pyrochlore does not affect the cell parameter, which for the phases of pyrochlore-microlite series is 10.42 ± 0.01 Å. In a system with an excess of UO2, pyrochlores and microlites, containing uranium up to 0.2-0.3 atoms per formula unit (apfu), are formed. In the uranium-free system of betafites composition, perovskites and Ti-bearing pyrochlores are formed. U-pyrochlores of betafite series, containing 2Ti = Nb + Ta in moles, have cubic cell parameters of 10.26 ± 0.02 Å and U4+ isomorphic capacity of 0.4-0.5 apfu. In the pyrochlore structure, U4+ may substitute for Ca2+ and Na+ cations in the eightfold site. In pyrochlores of pyrochlore-microlite series, Ca2+ is replaced by U4+, while in pyrochlores of betafite series, U4+ replaces Na+. Phases with pyrochlore structure, containing U5+ and U6+ in the sixfold site, usually occupied by Nb5+, Ta5+, and Ti4+, are formed under oxidizing conditions (Cu-Cu2O buffer). They are characterized by low content of Nb5+, Ta5+ (<0.1 apfu), and anomalous behavior of the crystal lattice (compression, instead of expansion). Under natural conditions, the formation of pyrochlores containing a significant amount of U5+ and U6+ is unlikely.

  12. Bacterial Diets of Primary Consumers at Hydrothermal Vents

    NASA Astrophysics Data System (ADS)

    Govenar, B.; Shank, T. M.

    2008-12-01

    Chemical energy produced by mixing hydrothermal fluids and seawater supports dense biological communities on mid-ocean ridges. The base of the food web at deep-sea hydrothermal vents is formed by chemolithoautotrophic bacteria that use the energy from the oxidation of reduced chemicals to fix inorganic carbon into simple sugars. With the exception of a few species that have chemolithoautotropic bacterial symbionts, most of the vent-endemic macrofauna are heterotrophs that feed on free-living bacteria, protists, and other invertebrates. The most abundant and diverse group of primary consumers in hydrothermal vent communities belong to the Gastropoda, particularly the patellomorph limpets. Gastropod densities can be as high as 2000 individuals m-2, and there can be as many as 13 species of gastropods in a single aggregation of the siboglinid tubeworm Riftia pachyptila and more than 40 species along the East Pacific Rise. Some gastropods are ubiquitous and others are found in specific microhabitats, stages of succession, or associated with different foundation species. To determine the mechanisms of species coexistence (e.g. resource partitioning or competition) among hydrothermal vent primary consumers and to track the flow of energy in hydrothermal vent communities, we employed molecular genetic techniques to identify the gut contents of four species of co-occurring hydrothermal vent gastropods, Eulepetopsis vitrea, Lepetodrilus elevatus, Lepetodrilus ovalis and Lepetodrilus pustulosus, collected from a single diffuse-flow hydrothermal vent site on the East Pacific Rise. Unique haplotypes of the 16S gene that fell among the epsilon-proteobacteria were found in the guts of every species, and two species had gut contents that were similar only to epsilon-proteobacteria. Two species had gut contents that also included haplotypes that clustered with delta-proteobacteria, and one species had gut contents that clustered with alpha- proteobacteria. Differences in the diets

  13. Development of Vertical Cable Seismic System for Hydrothermal Deposit Survey

    NASA Astrophysics Data System (ADS)

    Asakawa, E.; Sekino, Y.; Okamoto, T.; Murakami, F.; Mikada, H.; Takekawa, J.; Shimura, T.; Watanabe, Y.; Asakawa, K.

    2009-12-01

    Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots. Potential new deposits of lead-zinc-copper sulfide are generated by cooling hot water around the vents. There are about ten hydrothermal deposits founded around the water depth of 1000m along Izu-Ogasawara Trench and Okinawa-Trough in Japan. The deposits often exists in very thin layer and spatially limited area surrounded by complex seabottom feature like volcanic caldera. Some hydrothermal vents form roughly cylindrical chimney structures. In order to evaluate hydrothermal deposit, we have proposed the reflection seismic survey with vertical cable recording geometry, which is named as VCS (Vertical Cable Seismic). With this VCS, the following advantages will be provided for hydrothermal deposit survey. (1) It achieves 3D image within limited area which is necessary for estimating the complex hydrothermal deposit Typical hydrothermal deposit extend horizontally within 1km x 1km at the water depth of around 1000m. The conventional 3D seismic is not efficient for such limited target. (2) Seabottom condition is too rough to deploy ocean bottom sensors, such as OBC or OBS. Vertical cables are located on the seabottom, but the sensors are in the marine water. This is to avoid the coupling problems. With the use of the vertical hydrophone array, wavefield is able be separated. It can separate upgoing (reflection) and downgoing wave (direct wave and ghost) and distinguish the scattered waves in complex feature in hydrothermal area. (3) Various types of marine source are applicable with VCS such as sea-surface source (air gun, water gun etc.) or marine vibrator or ocean bottom source. This paper discusses the design of the surveys that can be the best for the 3D image of the target in the most economic way. We are interested in geometry of source and receiver distribution and the resultant target coverage. The first experiment is

  14. Variability in the microbial communities and hydrothermal fluid chemistry at the newly discovered Mariner hydrothermal field, southern Lau Basin

    NASA Astrophysics Data System (ADS)

    Takai, Ken; Nunoura, Takuro; Ishibashi, Jun-Ichiro; Lupton, John; Suzuki, Ryohei; Hamasaki, Hiroshi; Ueno, Yuichiro; Kawagucci, Shinsuke; Gamo, Toshitaka; Suzuki, Yohey; Hirayama, Hisako; Horikoshi, Koki

    2008-06-01

    A newly discovered hydrothermal field called the Mariner field on the Valu Fa Ridge in the southern Lau Basin was explored and characterized with geochemical and microbiological analyses. The hydrothermal fluid discharging from the most vigorous vent (Snow Chimney, maximum discharge temperature 365°C) was boiling at the seafloor at a depth of 1908 m, and two distinct end-member hydrothermal fluids were identified. The fluid chemistry of the typical Cl-enriched and Cl-depleted hydrothermal fluids was analyzed, as was the mineralogy of the host chimney structures. The variability in the fluid chemistry was potentially controlled by the subseafloor phase-separation (vapor loss process) and the microbial community activities. Microbial community structures in three chimney structures were investigated using culture-dependent and -independent techniques. The small subunit (SSU) rRNA gene clone analysis revealed that both bacterial and archaeal rRNA gene communities on the chimney surfaces differed among three chimneys. Cultivation analysis demonstrated significant variation in the culturability of various microbial components among the chimneys, particularly of thermophilic H2-oxidizing (and S-oxidizing) chemolithoautotrophs such as the genera Aquifex and Persephonella. The physical and chemical environments of chimney surface habitats are still unresolved and do not directly extrapolate the environments of possible subseafloor habitats. However, the variability in microbial community found in the chimneys also provides an insight into the different biogeochemical interactions potentially affected by the phase separation of the hydrothermal fluids in the subseafloor hydrothermal habitats. In addition, comparison with other deep-sea hydrothermal systems revealed that the Mariner field microbial communities have unusual characteristics.

  15. Hydrothermal acid treatment for sugar extraction from Golenkinia sp.

    PubMed

    Choi, Sun-A; Choi, Won-Il; Lee, Jin-Suk; Kim, Seung Wook; Lee, Gye-An; Yun, Jihyun; Park, Ji-Yeon

    2015-08-01

    In this study, hydrothermal acid treatment for efficient recovery of sugar from Golenkinia sp. was investigated. The initial glucose and XMG (xylose, mannose, and galactose) contents of a prepared Golenkinia sp. solution (40g/L) were 15.05 and 5.24g/L, respectively. The microalgal cell walls were hydrolyzed, for sugar recovery, by enzymatic saccharification and/or hydrothermal acid treatment. Among the various hydrothermal acid treatment conditions, the most optimal were the 2.0% H2SO4 concentration at 150°C for 15min, under which the glucose- and XMG-extraction yields were 71.7% and 64.9%, respectively. By pH 4.8, 50°C enzymatic hydrolysis after optimal hydrothermal acid treatment, the glucose- and XMG-extraction yields were additionally increased by 8.3% and 0.8%, respectively. After hydrothermal acid treatment, the combination with the enzymatic hydrolysis process improved the total sugar yield of Golenkinia sp. to 75.4%.

  16. Geologic evolution of the Lost City Hydrothermal Field

    NASA Astrophysics Data System (ADS)

    Denny, Alden R.; Kelley, Deborah S.; Früh-Green, Gretchen L.

    2016-02-01

    The Lost City Hydrothermal Field (LCHF) is a novel serpentinite-hosted vent field located on the Atlantis Massif southern wall. Results of 2 m resolution bathymetry, side scan, and video and still imagery, integrated with direct submersible observations provide the first high-resolution geologic map of the LCHF. These data form the foundation for an evolutionary model for the vent system over the past >120,000 years. The field is located on a down-dropped bench 70 m below the summit of the massif. The bench is capped by breccia and pelagic carbonate deposits underlain by variably deformed and altered serpentinite and gabbroic rocks. Hydrothermal activity is focused at the 60 m tall, 100 m across, massive carbonate edifice "Poseidon," which is venting 91°C fluid. Hydrothermal activity declines south and west of the Poseidon complex and dies off completely at distances greater than 200 m. East of Poseidon, the most recent stage of hydrothermal flow is characterized by egress of diffuse fluids from narrow fissures within a low-angle, anastomosing mylonite zone. South of the area of current hydrothermal activity, there is evidence of two discrete previously unrecognized relict fields. Active venting sites defined by carbonate-filled fissures that cut the carbonate cap rock at the summit of the massif mark the present-day northernmost extent of venting. These spatial relationships reflect multiple stages of field development, the northward migration of venting over time, and the likely development of a nascent field at the massif summit.

  17. Concerns of Hydrothermal Degradation in CAD/CAM Zirconia

    PubMed Central

    Kim, J.-W.; Covel, N.S.; Guess, P.C.; Rekow, E.D.; Zhang, Y.

    2010-01-01

    Zirconia-based restorations are widely used in prosthetic dentistry; however, their susceptibility to hydrothermal degradation remains elusive. We hypothesized that CAD/CAM machining and subsequent surface treatments, i.e., grinding and/or grit-blasting, have marked effects on the hydrothermal degradation behavior of Y-TZP. CAD/CAM-machined Y-TZP plates (0.5 mm thick), both with and without subsequent grinding with various grit sizes or grit-blasting with airborne alumina particles, were subjected to accelerated aging tests in a steam autoclave. Results showed that the CAD/CAM-machined surfaces initially exhibited superior hydrothermal degradation resistance, but deteriorated at a faster rate upon prolonged autoclave treatment compared with ground and grit-blasted surfaces. The accelerated hydrothermal degradation of CAD/CAM surfaces is attributed to the CAD/CAM machining damage and the absence of surface compressive stresses in the fully sintered material. Clinical relevance for surface treatments of zirconia frameworks in terms of hydrothermal and structural stabilities is addressed. PMID:19966039

  18. Concerns of hydrothermal degradation in CAD/CAM zirconia.

    PubMed

    Kim, J-W; Covel, N S; Guess, P C; Rekow, E D; Zhang, Y

    2010-01-01

    Zirconia-based restorations are widely used in prosthetic dentistry; however, their susceptibility to hydrothermal degradation remains elusive. We hypothesized that CAD/CAM machining and subsequent surface treatments, i.e., grinding and/or grit-blasting, have marked effects on the hydrothermal degradation behavior of Y-TZP. CAD/CAM-machined Y-TZP plates (0.5 mm thick), both with and without subsequent grinding with various grit sizes or grit-blasting with airborne alumina particles, were subjected to accelerated aging tests in a steam autoclave. Results showed that the CAD/CAM-machined surfaces initially exhibited superior hydrothermal degradation resistance, but deteriorated at a faster rate upon prolonged autoclave treatment compared with ground and grit-blasted surfaces. The accelerated hydrothermal degradation of CAD/CAM surfaces is attributed to the CAD/CAM machining damage and the absence of surface compressive stresses in the fully sintered material. Clinical relevance for surface treatments of zirconia frameworks in terms of hydrothermal and structural stabilities is addressed.

  19. Geochemical constraints on chemolithoautotrophic reactions in hydrothermal systems

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.; Mccollom, Thomas; Schulte, Mithell D.

    1995-01-01

    Thermodynamic calculations provide the means to quantify the chemical disequilibrium inherent in the mixing of reduced hydrothermal fluids with seawater. The chemical energy available for metabolic processes in these environments can be evaluated by taking into account the pressure and temperature dependence of the apparent standard Gibbs free energies of reactions in the S-H2-H2O system together with geochemical constraints on pH, activities of aqueous sulfur species and fugacities of H2 and/or O2. Using present-day mixing of hydrothermal fluids and seawater as a starting point, it is shown that each mole of H2S entering seawater from hydrothermal fluids represents about 200,000 calories of chemical energy for metabolic systems able to catalyze H2S oxidation. Extrapolating to the early Earth, which was likely to have had an atmosphere more reduced than at present, shows that this chemical energy may have been a factor of two or so less. Nevertheless, mixing of hydrothermal fluids with seawater would have been an abundant source of chemical energy, and an inevitable consequence of the presence of an ocean on an initially hot Earth. The amount of energy available was more than enough for organic synthesis from CO2 or CO, and/or polymer formation, indicating that the vicinity of hydrothermal systems at the sea floor was an ideal location for the emergence of the first chemolithoautotrophic metabolic systems.

  20. Comparison of 14C ages of hydrothermal petroleums

    USGS Publications Warehouse

    Simoneit, B.R.T.; Kvenvolden, K.A.

    1994-01-01

    In order to set limits on the time frame of formation of hydrothermal petroleum, we have obtained 14C ages on samples from three diverse regions; Gulf of California (Guaymas Basin), Northeast Pacific Ocean (Escanaba Trough and Middle Valley), and the East African Rift (Tanganyika Trough). The results date the source of carbon and therefore provide maximum ages for the formation and emplacement of the hydrothermal petroleums. The youngest petroleum occurs iin the Souther Trough of Guaymas Basin (3200-6600 yr, mean 4692 yr); in the Northern Trough the petroleum is slightly older (7400 yr). Significantly older hydrothermal petroleum occurs in Escanaba Trough (17,000 yr) and Middle Valley (29,000 yr). A continental example from the East African Rift has an age of 25,000 yr, comparable to the ages observed in the oceanic samples from the Northeast Pacific Ocean. These ages affirm that hydrothermal petroleum formation is a very rapid process and took place some time between the latest Pleistocene and the present in these active hydrothermal systems. ?? 1994.

  1. Shallow Submarine Hydrothermal Systems in the Aeolian Volcanic Arc, Italy

    NASA Astrophysics Data System (ADS)

    Monecke, Thomas; Petersen, Sven; Lackschewitz, Klas; Hügler, Michael; Hannington, Mark D.; Gemmell, J. Bruce

    2009-03-01

    The majority of known high-temperature hydrothermal vents occur at mid-ocean ridges and back-arc spreading centers, typically at water depths from 2000 to 4000 meters. Compared with 30 years of hydrothermal research along spreading centers in the deep parts of the ocean, exploration of the approximately 700 submarine arc volcanoes is relatively recent [de Ronde et al., 2003]. At these submarine arc volcanoes, active hydrothermal vents are located at unexpectedly shallow water depth (95% at <1600-meter depth), which has important consequences for the style of venting, the nature of associated mineral deposits, and the local biological communities. As part of an ongoing multinational research effort to study shallow submarine volcanic arcs, two hydrothermal systems in the submerged part of the Aeolian arc have been investigated in detail during research cruises by R/V Poseidon (July 2006) and R/V Meteor (August 2007). Comprehensive seafloor video surveys were conducted using a remotely operated vehicle, and drilling to a depth of 5 meters was carried out using a lander-type submersible drill. This research has resulted in the first detailed, three-dimensional documentation of shallow submarine hydrothermal systems on arc volcanoes.

  2. Magma to Microbe: Modeling Hydrothermal Processes at Ocean Spreading Centers

    NASA Astrophysics Data System (ADS)

    Lowell, Robert P.; Seewald, Jeffrey S.; Metaxas, Anna; Perfit, Michael R.

    Hydrothermal systems at oceanic spreading centers reflect the complex interactions among transport, cooling and crystallization of magma, fluid circulation in the crust, tectonic processes, water-rock interaction, and the utilization of hydrothermal fluids as a metabolic energy source by microbial and macro-biological ecosystems. The development of mathematical and numerical models that address these complex linkages is a fundamental part the RIDGE 2000 program that attempts to quantify and model the transfer of heat and chemicals from "mantle to microbes" at oceanic ridges. This volume presents the first "state of the art" picture of model development in this context. The most outstanding feature of this volume is its emphasis on mathematical and numerical modeling of a broad array of hydrothermal processes associated with oceanic spreading centers. By examining the state of model development in one volume, both cross-fertilization of ideas and integration across the disparate disciplines that study seafloor hydrothermal systems is facilitated. Students and scientists with an interest in oceanic spreading centers in general and more specifically in ridge hydrothermal processes will find this volume to be an up-to-date and indispensable resource.

  3. Evidence for Hesperian Impact-Induced Hydrothermalism on Mars

    NASA Technical Reports Server (NTRS)

    Marzo, Giuseppe A.; Davila, Alfonso F.; Tornabene, Livio L.; Dohm, James M.; Fairen, Alberto G.; Gross, Christoph; Kneissl, Thomas; Bishop, Janice L.; Roush, Ted L.; McKay, Chris P.

    2010-01-01

    Several hydrated silicate deposits on Mars are observed within craters and are interpreted as excavated Noachian material. Toro crater (71.8 deg E, 17.0 deg N), located on the northern edge of the Syrtis Major Volcanic Plains, shows spectral and morphologic evidence of impact-induced hydrothermal activity. Spectroscopic observations were used to identify extensive hydrated silicate deposits, including prehnite, chlorites, smectites, and opaline material, a suite of phases that frequently results from hydrothermal alteration in terrestrial craters and also expected on Mars from geochemical modeling of hydrothermal environments. When combined with altimetry and high-resolution imaging data, these deposits appear associated predominantly with the central uplift and with portions of the northern part of the crater floor. Detailed geologic mapping of these deposits reveals geomorphic features that are consistent with hydrothermal activity that followed the impact event, including vent-like and conical mound structures, and a complex network of tectonic structures caused by fluid interactions such as fractures and joints. The crater age has been calculated from the cumulative crater size-frequency distributions and is found to be Early Hesperian. The evidence presented here provides support for impact-induced hydrothermal activity in Toro crater, that extends phyllosilicate formation processes beyond the Noachian era.

  4. Prediction of microalgae hydrothermal liquefaction products from feedstock biochemical composition

    SciTech Connect

    Leow, Shijie; Witter, John R.; Vardon, Derek R.; Sharma, Brajendra K.; Guest, Jeremy S.; Strathmann, Timothy J.

    2015-05-11

    Hydrothermal liquefaction (HTL) uses water under elevated temperatures and pressures (200–350 °C, 5–20 MPa) to convert biomass into liquid “biocrude” oil. Despite extensive reports on factors influencing microalgae cell composition during cultivation and separate reports on HTL products linked to cell composition, the field still lacks a quantitative model to predict HTL conversion product yield and qualities from feedstock biochemical composition; the tailoring of microalgae feedstock for downstream conversion is a unique and critical aspect of microalgae biofuels that must be leveraged upon for optimization of the whole process. This study developed predictive relationships for HTL biocrude yield and other conversion product characteristics based on HTL of Nannochloropsis oculata batches harvested with a wide range of compositions (23–59% dw lipids, 58–17% dw proteins, 12–22% dw carbohydrates) and a defatted batch (0% dw lipids, 75% dw proteins, 19% dw carbohydrates). HTL biocrude yield (33–68% dw) and carbon distribution (49–83%) increased in proportion to the fatty acid (FA) content. A component additivity model (predicting biocrude yield from lipid, protein, and carbohydrates) was more accurate predicting literature yields for diverse microalgae species than previous additivity models derived from model compounds. FA profiling of the biocrude product showed strong links to the initial feedstock FA profile of the lipid component, demonstrating that HTL acts as a water-based extraction process for FAs; the remainder non-FA structural components could be represented using the defatted batch. These findings were used to introduce a new FA-based model that predicts biocrude oil yields along with other critical parameters, and is capable of adjusting for the wide variations in HTL methodology and microalgae species through the defatted batch. Lastly, the FA model was linked to an upstream cultivation model (Phototrophic Process Model

  5. The Kinetic Behavior of Benzaldehyde under Hydrothermal Conditions

    NASA Astrophysics Data System (ADS)

    Fecteau, K.; Gould, I.; Hartnett, H. E.; Williams, L. B.; Shock, E.

    2013-12-01

    Aldehydes represent an intermediate redox state between alcohols and carboxylic acids and are likely intermediates in the transformation of organic compounds in natural systems. We have conducted kinetic studies of a model aldehyde, benzaldehyde, in high-temperature water (250-350 °C, saturation pressure) in clear fused quartz (CFQ) autoclaves. Under these conditions, benzaldehyde is observed to undergo a disproportionation reaction to benzyl alcohol and benzoic acid reminiscent of the base-catalyzed Cannizzaro reaction known to occur at cooler temperatures. Benzene is also produced via decarbonylation of the aldehyde. We have obtained pseudo second-order rate constants for the decomposition of benzaldehyde at 250, 300, and 350 °C. Rates derived via repeated heating phases and subsequent quantitative 13C-NMR spectroscopy of a single NMR-compatible CFQ tube containing isotopically labeled benzaldehyde are consistent with those obtained by analysis of product suites from individual timed experiments via gas chromatography. Arrhenius parameters for these rate constants are consistent with published values for the reaction under supercritical conditions from one study (Tsao et al. 1992) yet the pre-exponential factor is approximately 7 orders of magnitude smaller than that derived from another study (Ikushima et al. 2001). Moreover, fitting our rate constants with the Eyring equation yields an entropy of activation (ΔS‡) of -26.6 kcal mol-1 K-1, which is consistent for a bimolecular transition state at the rate-limiting step. In contrast, the rates of Ikushima et al. yield a positive value of ΔS‡, which is inconsistent with the putative mechanism for the reaction. The linear Arrhenius behavior of the decomposition of benzaldehyde from high-temperature liquid to supercritical conditions demonstrates the potential for extrapolating experimentally derived rates of reactions for organic functional group transformations to conditions where diagenesis, alteration

  6. Prediction of microalgae hydrothermal liquefaction products from feedstock biochemical composition

    DOE PAGESBeta

    Leow, Shijie; Witter, John R.; Vardon, Derek R.; Sharma, Brajendra K.; Guest, Jeremy S.; Strathmann, Timothy J.

    2015-05-11

    Hydrothermal liquefaction (HTL) uses water under elevated temperatures and pressures (200–350 °C, 5–20 MPa) to convert biomass into liquid “biocrude” oil. Despite extensive reports on factors influencing microalgae cell composition during cultivation and separate reports on HTL products linked to cell composition, the field still lacks a quantitative model to predict HTL conversion product yield and qualities from feedstock biochemical composition; the tailoring of microalgae feedstock for downstream conversion is a unique and critical aspect of microalgae biofuels that must be leveraged upon for optimization of the whole process. This study developed predictive relationships for HTL biocrude yield and othermore » conversion product characteristics based on HTL of Nannochloropsis oculata batches harvested with a wide range of compositions (23–59% dw lipids, 58–17% dw proteins, 12–22% dw carbohydrates) and a defatted batch (0% dw lipids, 75% dw proteins, 19% dw carbohydrates). HTL biocrude yield (33–68% dw) and carbon distribution (49–83%) increased in proportion to the fatty acid (FA) content. A component additivity model (predicting biocrude yield from lipid, protein, and carbohydrates) was more accurate predicting literature yields for diverse microalgae species than previous additivity models derived from model compounds. FA profiling of the biocrude product showed strong links to the initial feedstock FA profile of the lipid component, demonstrating that HTL acts as a water-based extraction process for FAs; the remainder non-FA structural components could be represented using the defatted batch. These findings were used to introduce a new FA-based model that predicts biocrude oil yields along with other critical parameters, and is capable of adjusting for the wide variations in HTL methodology and microalgae species through the defatted batch. Lastly, the FA model was linked to an upstream cultivation model (Phototrophic Process Model

  7. Hydrothermal degradation of lignin: products analysis for phenol formaldehyde adhesive synthesis.

    PubMed

    Yang, Sheng; Yuan, Tong-Qi; Li, Ming-Fei; Sun, Run-Cang

    2015-01-01

    Corncob lignin was treated with pressurized hot water in a cylindrical autoclave in current investigation. With the aim of investigating the effect of reaction temperature and retention time on the distribution of degradation products, the products were divided into five fractions including gas, volatile organic compounds, water-soluble oil, heavy oil, and solid residue. It was found that hydrothermal degradation of corncob lignin in pressurized hot water produced a large amount of phenolic compounds with lower molecular weight than the raw lignin. Some phenolic and benzene derivatives monomers such as vanillin, 2-methoxy-phenol, 2-ethyl-phenol, p-xylene, and 1, 3-dimethyl-benzene were also identified in the degradation products. The products were further analyzed by GC-MS, GPC, 2D-HSQC, and (31)P-NMR to investigate their suitability for partial incorporation into phenol formaldehyde adhesive as a substitution of phenol. The results indicated that the reaction temperature had more effect on the products distribution than the retention time. The optimal condition for heavy oil production appeared at 290 °C with retention time 0 min. The compounds of heavy oil had more active sites than the raw lignin, suggesting that the heavy oil obtained from hydrothermal degradation of lignin is a promising material for phenol formaldehyde adhesive synthesis.

  8. Synthesis of hydrothermally stable, hierarchically mesoporous aluminosilicate Al-SBA-1 and their catalytic properties

    NASA Astrophysics Data System (ADS)

    Li, Na; Wang, Jin-Gui; Xu, Jian-Xiong; Liu, Jin-Yu; Zhou, Hui-Jing; Sun, Ping-Chuan; Chen, Tie-Hong

    2012-03-01

    Hydrothermally stable mesoporous aluminosilicates Al-SBA-1 with hierarchical pore structure have been successfully synthesized under alkaline condition at 120 °C by employing organic mesomorphous complexes of polyelectrolyte (poly(acrylic acid) (PAA)) and cationic surfactant (hexadecyl pyridinium chloride (CPC)) as template. The Si/Al ratio could be as high as 5 and the incorporation of Al into the silica framework did not disturb the well-ordered cubic Pm3&cmb.macr;n mesostructure. Meanwhile, the incorporation of Al could greatly increase the specific surface area and pore volume of the samples. The Al-SBA-1 materials exhibited a high hydrothermal stability and remained stable even after being treated in boiling water for 10 days. The catalytic activity of the Al-SBA-1 materials was investigated by employing the Friedel-Crafts alkylation of toluene with benzyl alcohol as a model reaction and they exhibited excellent catalytic property due to the incorporated acid sites and the hierarchically mesoporous structure.

  9. Hydrothermal removal of Sr2+ in aqueous solution via formation of Sr-substituted hydroxyapatite.

    PubMed

    Tan, Sheng-Heng; Chen, Xue-Gang; Ye, Ying; Sun, Jie; Dai, Ling-Qing; Ding, Qian

    2010-07-15

    We removed Sr(2+) in simulating wastewater and simultaneously prepared Sr-substituted hydroxyapatite via chemical precipitation and hydrothermal treatment. Both higher initial pH value and higher molar ratio of Sr/(Sr+Ca) contributed to lower residual Sr(2+) concentration and higher removal efficiency. About two thirds of Sr(2+) residual in solution after chemical precipitation were further reduced by hydrothermal treatment. The optimal Sr removal result was 99.66% with an ultimate concentration of 2.0 mg L(-1) when the initial pH was 12 and Sr/(Sr+Ca) was 0.2. Sr-substituted hydroxyapatite phase with hexagonal structure was identified by XRD and EDS results. However, it was found that SrHPO(4) phase was formed in the samples with high Sr composition. The lattice constants became larger with the increase of Sr(2+) and the crystallinity became higher with the increase of pH value. Rod-like particles were observed in SEM images of synthesized Sr-substituted hydroxyapatite samples, with the size of 20-30 nm in width and 70-100 nm in length. With little secondary waste and simple treating procedure, this method is an effective and prospective measure to deal with (90)Sr in nuclear waste and industry wastewater.

  10. Hydrothermal reactions of fly ash. [Quarterly report], April 1, 1992--June 31, 1992

    SciTech Connect

    Brown, P.W.

    1992-08-01

    The reactions which occur when fly ash is treated under hydrothermal conditions will be investigated. This will be done for two primary reasons. The first of these is to determine the nature of the phases that form, to assess the stabilities of these phases in the ambient environment and, finally, to assess whether these phases are capable of sequestering hazardous species. The second reason for undertaking this proposed study is that, depending on the composition of the ash and the presence of selected additives, it may be possible under hydrothermal conditions to form compounds which have cementitious properties. Formation of four classes of compounds which bracket likely fly ash compositional ranges, have been selected for study. These are calcium silicate hydrates, calcium silicosulfates, calcium aluminosulfates, and alkali aluminosilicates. The specific compounds fabricated will be determined and their stability regions assessed. As a part of stability assessment, the extent to which selected hazardous species are sequestered seal be determined. Finally, the cementing properties of these compounds will be established.

  11. PREFACE: Functionalized Liquid Liquid Interfaces

    NASA Astrophysics Data System (ADS)

    Girault, Hubert; Kornyshev, Alexei A.; Monroe, Charles W.; Urbakh, Michael

    2007-09-01

    Most natural processes take place at interfaces. For this reason, surface science has been a focal point of modern research. At solid-liquid interfaces one can induce various species to adsorb or react, and thus may study interactions between the substrate and adsorbates, kinetic processes, optical properties, etc. Liquid-liquid interfaces, formed by immiscible liquids such as water and oil, have a number of distinctive features. Both sides of the interface are amenable to detailed physical and chemical analysis. By chemical or electrochemical means, metal or semiconductor nanoparticles can be formed or localised at the interface. Surfactants can be used to tailor surface properties, and also to place organic molecular or supermolecular constructions at the boundary between the liquids. Electric fields can be used to drive ions from one fluid to another, or even change the shape of the interface itself. In many cases, both liquids are optically transparent, making functionalized liquid-liquid interfaces promising for various optical applications based on the transmission or reflection of light. An advantage common to most of these systems is self-assembly; because a liquid-liquid interface is not mechanically constrained like a solid-liquid interface, it can easily access its most stable state, even after it has been driven far from equilibrium. This special issue focuses on four modes of liquid-liquid interfacial functionalization: the controlled adsorption of molecules or nanoparticles, the formation of adlayers or films, electrowetting, and ion transfer or interface-localized reactions. Interfacial adsorption can be driven electrically, chemically, or mechanically. The liquid-liquid interface can be used to study how anisotropic particles orient at a surface under the influence of a field, how surfactants interact with other adsorbates, and how nanoparticles aggregate; the transparency of the interface also makes the chirality of organic adsorbates amenable to

  12. Convective thermocapillary instabilities in liquid bridges. [for study of crystal growth in reduced gravity

    NASA Technical Reports Server (NTRS)

    Xu, J.-J.; Davis, S. H.

    1984-01-01

    A steady shear flow is generated in an axisymmetric liquid bridge surrounded by a passive gas through the imposition of a temperature gradient along the bridge and the driving of the motion by thermocapillarity. This dynamic state is susceptible to convective instabilities, which can lead to propagating hydrothermal waves that feed on the underlying temperature gradients. The convective instabilities of axisymmetric return flow are presently given as functions of the liquid's Prandtl number and the surface Biot number of the interface.

  13. Distribution, structure and temporal variability of hydrothermal outflow at a slow-spreading hydrothermal field from seafloor image mosaics.

    NASA Astrophysics Data System (ADS)

    Barreyre, Thibaut; Escartin, Javier; Cannat, Mathilde; Garcia, Rafael; Science Party, Momar'08; Science Party, Bathyluck'09

    2010-05-01

    The Lucky Strike hydrothermal site, located South of the Azores along the Mid-Atlantic Ridge, is one of the largest and best-known active hydrothermal fields along the ridge system. This site within the MoMAR area is also the target for the installation in 2010 of a pilot deep-sea observatory with direct telemetry to land, to be part of the European Seafloor Observatory Network (ESONET). The Lucky Strike hydrothermal site has seen extensive high-resolution, near-bottom geophysical surveys in 1996 (Lustre'96), 2006 (Momareto06), 2008 (MOMAR08) and 2009 (Bathyluck09). Vertically acquired black-and-white electronic still camera images have been projected and georeferenced to obtain 3 image mosaics covering the zone of active venting, extending ~ 700x800 m2, and with full image resolution (~10 mm pixels). These data allow us to study how hydrothermal outflow is structured, including the relationships between the zones of active high-temperature venting, areas of diffuse outflow, and the geological structure (nature of the substrate, faults and fissures, sediments, etc.). Hydrothermal outflow is systematically associated with bacterial mats that are easily identified in the imagery, allowing us to study temporal variability at two different scales. Over the 13-year period we can potentially track changes in both the geometry and intensity of hydrothermal activity throughout the system; our preliminary study of the Eiffel Tower, White Castle and Mt Segur indicate that activity has been sustained in recent times, with small changes in the detailed geometry of the diffuse outflow and its intensity. At longer times scales (hundreds to 1000 years?) imagery also shows evidence of areas of venting that are no longer active, often associated with the active structures. In combination with the high-resolution bathymetry, the imagery data thus allow us to characterize the shallow structure of hydrothermal outflow at depth, the structural and volcanic control, and ultimately

  14. Geology, alteration, and magmatic-hydrothermal history of The Geysers felsite -- potential applications for exploration and development

    SciTech Connect

    Hulen, J.B.; Nielson, D.L. )

    1993-01-01

    The [open quotes]felsite[close quotes] is a shallow, young, granitic intrusive body centrally located within and beneath. The Geysers steam field. The field and the felsite are coaxial, and hydrothermal alteration effected by hot-water dominated geothermal systems antedating the modern steam reservoir shows systematic vertical zonation with respect to the pluton. The research summarized in this communication was undertaken both to clarify the role of the pluton in reservoir evolution, and to characterize critical felsite-specific controls on the fields's deep porosity and permeability. The felsite comprises at least three major intrusive phases. Two are high-silica granites probably older than 1.3 Ma. The third is granodiorite (1 Ma), temporally and chemically equivalent to overlying extrusive dacites of the Clear Lake volcanic field. All three intrusive phases are too old to be heat sources for the modern steam field, but probably were the heat engines for the prior liquid-dominant systems. Younger, deeper magmatic heat sources are strongly implied for the current vapor-dominated regime. Porosity in the felsite is provided by: (1) Extensively mineralized fractures and breccias, probably of both tectonic and high-temperature hydrothermal origin; and (2) miarolitic cavities in the upper levels of the pluton. The latter could be analogous to calcite-dissolution cavities in overlying metagraywacke -- they could serve as storage sites for the fields's liquid water reserves. Porosity in these fractures, breccias, and vugs in partially occluded by hydrothermal vein minerals deposited in prior hotwater-dominated systems --tourmaline, ferroaxinite, quartz, potassium feldspar, epidote, actinolite, prehnite, and many others. Such secondary mineralization conceptually could serve as an excellent exploration guide to potentially productive portions of the felsite beyond the field's present boundaries.

  15. Copper sulfate: Liquid or crystals?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two separate experiments were conducted to evaluate copper toxicity to channel catfish and free-swimming Ichthyophthirius multifiliis or Ich (the stage of Ich that can be treated); the compounds we used were CuSO4 crystals and a non-chelated liquid CuSO4 product. In 96 hr tests conducted in aquaria...

  16. Fractionation of Boron Isotopes in Icelandic Hydrothermal Systems

    SciTech Connect

    Aggarwal, J.K.; Palmer, M.R.

    1995-01-01

    Boron isotope ratios have been determined in a variety of different geothermal waters from hydrothermal systems across Iceland. Isotope ratios from the high temperature meteoric water recharged systems reflect the isotope ratio of the host rocks without any apparent fractionation. Seawater recharged geothermal systems exhibit more positive {delta}{sup 11}B values than the meteoric water recharged geothermal systems. Water/rock ratios can be assessed from boron isotope ratios in the saline hydrothermal systems. Low temperature hydrothermal systems also exhibit more positive {delta}{sup 11}B than the high temperature systems, indicating fractionation of boron due to adsorption of the lighter isotope onto secondary minerals. Fractionation of boron in carbonate deposits may indicate the level of equilibrium attained within the systems.

  17. Energetics of amino acid synthesis in hydrothermal ecosystems

    NASA Technical Reports Server (NTRS)

    Amend, J. P.; Shock, E. L.

    1998-01-01

    Thermodynamic calculations showed that the autotrophic synthesis of all 20 protein-forming amino acids was energetically favored in hot (100 degrees C), moderately reduced, submarine hydrothermal solutions relative to the synthesis in cold (18 degrees C), oxidized, surface seawater. The net synthesis reactions of 11 amino acids were exergonic in the hydrothermal solution, but all were endergonic in surface seawater. The synthesis of the requisite amino acids of nine thermophilic and hyperthermophilic proteins in a 100 degreesC hydrothermal solution yielded between 600 and 8000 kilojoules per mole of protein, which is energy that is available to drive the intracellular synthesis of enzymes and other biopolymers in hyperthermophiles thriving in these ecosystems.

  18. Coordination Hydrothermal Interconnection Java-Bali Using Simulated Annealing

    NASA Astrophysics Data System (ADS)

    Wicaksono, B.; Abdullah, A. G.; Saputra, W. S.

    2016-04-01

    Hydrothermal power plant coordination aims to minimize the total cost of operating system that is represented by fuel costand constraints during optimization. To perform the optimization, there are several methods that can be used. Simulated Annealing (SA) is a method that can be used to solve the optimization problems. This method was inspired by annealing or cooling process in the manufacture of materials composed of crystals. The basic principle of hydrothermal power plant coordination includes the use of hydro power plants to support basic load while thermal power plants were used to support the remaining load. This study used two hydro power plant units and six thermal power plant units with 25 buses by calculating transmission losses and considering power limits in each power plant unit aided by MATLAB software during the process. Hydrothermal power plant coordination using simulated annealing plants showed that a total cost of generation for 24 hours is 13,288,508.01.

  19. Progress report on modeling studies: Natural state conditions and exploitation of the Dachny geothermal reservoir, Mutnovsky hydrothermal system, Kamchatka, Russia

    SciTech Connect

    Kiryukhin, A.V.

    1992-07-01

    The spat