WorldWideScience

Sample records for chimneys

  1. Fairy chimneys in Peru

    CERN Document Server

    Sparavigna, Amelia Carolina

    2011-01-01

    Erosion creates beautiful landscapes. A large part of them is known just by the local population. Google Maps can help in locating the places, study them and start any project for preservation. An interesting example is given by a landscape of fairy chimneys in Peru, near San Pedro de Larcay. It is remarkable the fact that some of them have been adapted as dwelling places.

  2. Toward a Heat Recovery Chimney

    Directory of Open Access Journals (Sweden)

    Min Pan

    2011-11-01

    Full Text Available The worldwide population increase and subsequent surge in energy demand leads electricity producers to increase supply in an attempt to generate larger profit margins. However, with Global Climate Change becoming a greater focus in engineering, it is critical for energy to be converted in as environmentally benign a way as possible. There are different sustainable methods to meet the energy demand. However, the focus of this research is in the area of Waste Heat Recovery. The waste heat stored in the exiting condenser cooling water is delivered to the air flow through a water-air cross flow heat exchanger. A converging thermal chimney structure is then applied to increase the velocity of the airflow. The accelerated air can be used to turn on the turbine-generator installed on the top the thermal chimney so that electricity can be generated. This system is effective in generating electricity from otherwise wasted heat.

  3. Psychology and photography: chimneys dreaming and chimneys warriors

    Directory of Open Access Journals (Sweden)

    Tilde Giani Gallino

    2013-02-01

    Full Text Available The article covers two aspects related to Psychology and Art. The first aspect concerns the similarities found between photography and various Schools of experimental psychology. For instance, the scientists of Psychology of ethological theory, and Non-verbal communication (NVC, observe with particular methodologies the non-verbal messages that animals and humans transmit to their peers through expressions, posture, gestures. The same is done by photographers (those who use the “camera” with a good knowledge of the medium and a “photographic  eye” when they look around, careful to catch an expression, any unusual attitude, or a gesture of friendship. Another School of psychology, the Gestalpsychologie (Gestalt: form, figure, configuration, attributes a decisive value to the perception of space, the foreground and the background, the perspective and vanishing points, the contrast between black and white. All aspects that effectively interest psychologists just as much as photographers. Finally, the second aspect relates to the art of Antony Gaudì and makes some hypothesis about the personality and behavior of the great architect, with regard to the construction of two houses, "Casa Batllo" and "Casa Mila": particularly because of the configuration or Gestalt of the "chimneys" that dominate the two buildings. In this study, cooperate each other psychological analysis and the art of photography. The last enables us to study also the details of the work of Gaudì, as can be seen in the pictures of this essay.

  4. Evaluation of corrosion attack of chimney liners

    OpenAIRE

    Blahetová M.; Horák J.; Kubesa P.; Lasek S.; Ochodek T.

    2016-01-01

    The case study of chimney liner corrosion addresses three specific cases of damage of chimney systems from of stainless steels. These systems were used for flue of gas arising from the combustion of brown coal in small automatic boilers, which are used for heating. Detailed analyzes implied that the cause of devastating corrosion of the steel AISI 316 and 304 steel (CSN 17349, 17241) was particularly high content of halides (chlorides and fluorides), which caused a severe pitting corrosion, w...

  5. Toy models for the falling chimney

    CERN Document Server

    Varieschi, G U; Varieschi, Gabriele; Kamiya, Kaoru

    2003-01-01

    In this paper we review the theory of the ``falling chimney'', which deals with the breaking in mid-air of tall structures, when they fall to the ground. We show that these ruptures can be caused by either shear forces, typically developing near the base, or by the bending of the structure, which is caused primarily by the internal bending moment. In the latter case the breaking is more likely to occur between one third and one half of the height of the chimney. Small scale toy models are used to reproduce the dynamics of the falling chimney. By examining photos taken during the fall of these models we test the adequacy of the outlined theory. This type of experiment, easy to perform and conceptually challenging, can become part of a rotational mechanics lab for undergraduate students.

  6. Evaluation of corrosion attack of chimney liners

    Directory of Open Access Journals (Sweden)

    Blahetová M.

    2016-06-01

    Full Text Available The case study of chimney liner corrosion addresses three specific cases of damage of chimney systems from of stainless steels. These systems were used for flue of gas arising from the combustion of brown coal in small automatic boilers, which are used for heating. Detailed analyzes implied that the cause of devastating corrosion of the steel AISI 316 and 304 steel (CSN 17349, 17241 was particularly high content of halides (chlorides and fluorides, which caused a severe pitting corrosion, which led up to the perforation of the liner material. Simultaneous reduction of the thickness of the used sheets was due to by the general corrosion, which was caused by the sulfur in the solid fuel. The condensation then led to acid environment and therefore the corrosion below the dew point of the sulfuric acid has occurred. All is documented by metallographic analysis and microanalysis of the corrosion products.

  7. Design manual for HANARO in-chimney bracket

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Soo; Cho, Y. G.; Whang, S. Y.; Wu, J. S.; Jun, B. J

    2000-06-01

    As a supplementary structure supporting the irradiation facilities, the in-chimney bracket holds guide tubes whose holding position in CT or IR is the middle part of the instrumented facility between the hole spider and the robot arm already provided in the reactor pool liner. Also, the bracket grips the upper part of the guide tubes when it is applied to hold the instrumented facility loaded in OR sites. The irradiation test will be successfully conducted since this bracket reduces the flow-induced vibration (FIV) and the dynamic response to seismic load. The installation position of the bracket is 60 cm below the top of the chimney, i.e., thermo siphoning hole position. To evaluate the structural integrity on the in-chimney bracket and the related reactor structures, ANSYS finite element analysis model is developed and the dynamic characteristics are analyzed. The seismic response analyses were performed for the in-chimney bracket and the related reactor structures of HANARO under the design earthquake response spectrum loads of OBE and SSE. The analysis results show that the stress values in main points of reactor structures and in-chimney bracket for the seismic loads are also within the ASME code limits. It is also confirmed that the fatigue usage factor is much less than 1.0. Therefore any damage on structural integrity is not expected when the in-chimney bracket is installed at the upper part of the reactor chimney. This bracket had been designed and manufactured based on the dimensions of the as-built chimney. In the process of design and preliminary installation, chimney measurement tools, dummy chimney, and installation tools were developed and the installation procedure was prepared and verified through the installation rehearsal.

  8. Numerical simulation and exergetic analysis of building ventilation solar chimneys

    International Nuclear Information System (INIS)

    Highlights: • Exergetic analysis of a building ventilation solar chimney. • Numerical CFD model developed, validated and employed to study the flow. • Analysis of the solar chimney energy and exergy efficiencies. • Mechanical and thermal exergy distributions have been analysed. • Crucial points in the chimney identified to improve its performance. - Abstract: The solar chimneys used in buildings are passive solar devices which improve natural ventilation. A detailed exergetic analysis has been developed in this work, both for general balance and specific variables. To apply this analysis, a three-dimensional CFD model has been built and validated with bibliographic experimental data. The values of the variables have been examined both inside and at the exit of the solar chimney, resulting in a detailed description of the inner phenomena and parameters influencing the exergetic efficiency. The results of this study offer new tools: a numerical methodology and an exergetic analysis, to improve the design of building ventilation solar chimneys. It also affords a deeper understanding of the thermal and fluid-dynamic behaviour, and suggests some qualitative improvements. However, the numerical data obtained from the case studied, show that solar chimneys as natural ventilation systems offer quite a small efficiency and will remain within the sphere of architectural decisions

  9. Free-standing inflatable solar chimney: experiment and theory

    Science.gov (United States)

    Vorobieff, Peter; Mammoli, Andrea; Fathi, Nima; Putkaradze, Vakhtang

    2014-11-01

    Solar chimneys (or solar updraft towers) offer an attractive way to use solar energy for production of baseload power. In a power plant of this type, sunshine heats the air under a wide greenhouse-like roofed collector surrounding the central base of a tall chimney. The heated air drives an updraft flow through the tower, whose energy is harvested with turbines. For a sufficiently large plant of this type, the thermal mass of the heated ground under the collector is sufficient to drive the flow even when the sun is down. The primary challenge in building the solar chimney power plant is the construction of the chimney that generates the updraft, which must be very tall (hundreds of meters for a commercial-sized plant). Here we present a study of an inflatable chimney which is a self-supporting, deformable, free-standing stack of gas-filled tori. The structure is stabilized via a combination of shape, overpressure, and buoyancy. Theoretical considerations suggest that filling the tori with air rather than with a light gas may be advantageous for stability. The chimney shape is optimized for deformation under wind loading. A prototype chimney has demonstrated the viability of the concept, with experimental results in good agreement with theoretical predictions. This research is partially supported by the UNM Research Allocations Comittee (RAC) and UNM Center for Emerging Energy Technologies (CEET).

  10. Experimental Investigations on Performance and Design Parameters of Solar Chimney

    OpenAIRE

    İbrahim ÜÇGÜL; KOYUN, Arif

    2010-01-01

    In this study, a solar chimney system, which is suitable for climate conditions of Isparta and its surroundings, is designed theoretically. With the aim of studying experimentally as based on that design, a prototype solar chimney has been constructed in the university campus area of Süleyman Demirel University-RACRER (Research and Application Center for Renewable Energy Resources). Additionally, after the experimental studies, the system is modelled theoretically with depending on the design...

  11. Seismic response Analyses of Hanaro in-chimney bracket structures

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Han; Ryu, J.S.; Cho, Y.G.; Lee, H.Y.; Kim, J.B

    1999-05-01

    The in-chimney bracket will be installed in the upper part of chimney, which holds the capsule extension pipes in upper one-third of length. For evaluating the effects on the capsules and related reactor structures, ANSYS finite element analysis model is developed and the dynamic characteristics are analyzed. The seismic response anlayses of in-chimney bracket and related reactor structures of HANARO under the design earthquake response spectrum loads of OBE (0.1 g) and SSE (0.2 g) are performed. The maximum horizontal displacements of the flow tubes are within the minimum half gaps between close flow tubes, it is expected that these displacement will not produce any contact between neighbor flow tubes. The stress values in main points of reactor structures and in-chimney bracket for the seismic loads are also within the ASME Code limits. It is also confirmed that the fatigue usage factor is muchless than 1.0. So, any damage on structural integrity is not expected when an in-chimney bracket is installed to upper part of the reactor chimney. (author). 12 refs., 24 tabs., 37 figs.

  12. Experimental study for natural ventilation on a solar chimney

    Energy Technology Data Exchange (ETDEWEB)

    Arce, J. [Centro de Investigacion en Energia (CIE-UNAM), Termociencias, Priv. Xochicalco S/N Col. Centro, Temixco, Morelos, CP 62580 (Mexico); Jimenez, M.J.; Guzman, J.D.; Heras, M.R. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense, 22, E-28040 Madrid (Spain); Alvarez, G.; Xaman, J. [Centro Nacional de Investigacion y Desarrollo Tecnologico (CENIDET-DGEST-SEP), Prol. Av. Palmira S/N. Col. Palmira, Cuernavaca, Morelos, CP 62490 (Mexico)

    2009-12-15

    Thermal performance of a solar chimney for natural ventilation was experimentally investigated. The experimental model was implemented on full scale and real meteorological conditions, so that experimental results will be compared with the simulation results. The results show that for a maximum irradiance of 604 W/m{sup 2}, occurring around 13:00 h on September 15th, 2007, a maximum air temperature increment of 7 C was obtained through the solar chimney. Also, a volumetric air flow rate ranging from 50 to 374 m{sup 3}/h was measured on that day. Thus, an average air flow rate of 177 m{sup 3}/h was achieved from 0:00 h to 24:00 h. The experimental solar chimney discharge coefficient, C{sub d}, was 0.52. This coefficient is useful to determine the mass flow rate in the solar chimney design. It was observed that the air flow rate through the solar chimney is influenced by a pressure difference between input and output, caused by thermal gradients and wind velocity, mainly. (author)

  13. Experimental investigations of a chimney-dependent solar crop dryer

    Energy Technology Data Exchange (ETDEWEB)

    Afriyie, J.K.; Nazha, M.A.A.; Rajakaruna, H. [School of Engineering and Technology, De Montfort University, Queens Building, The Gateway, Leicester LE1 9BH (United Kingdom); Forson, F.K. [Department of Mechanical Engineering, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana)

    2009-01-15

    An experimental investigation into the performance of a solar crop dryer with solar chimney and no air preheating is described. Tests were first performed on the cabinet dryer, using a normal chimney. The trials were repeated with a solar chimney. Still with the solar chimney, further trials were carried out with the roof of the drying chamber inclined further to form a tent dryer. The described tests include no-load tests for airflow rate measurements and drying tests, with cassava as the crop. Air velocities, temperatures, ambient relative humidity and the drop in crop moisture contents at different stages of the drying process are also presented. The effects of the various configurations described above on the drying process are deduced and discussed while comparing the experimental results with one another. In addition, the performance of the dryer in relation to other natural convection dryers is discussed. The results show that the solar chimney can increase the airflow rate of a direct-mode dryer especially when it is well designed with the appropriate angle of drying-chamber roof. However, the increase in flow rate only increases the drying rate when the relative humidity (RH) of the ambient air is below a certain mark (60% for cassava). (author)

  14. Corrosion at system chimneys made of CrNi-steels

    Energy Technology Data Exchange (ETDEWEB)

    Pajonk, Gunther [Institute of Materials Testing of Northrhine-Westfalia, D-44285 Dortmund (Germany)

    2004-07-01

    Names like 'chimney' und 'funnel' usually identify flue gas devices made of bricks. Much less known is the fact that chimney elements are still manufactured from alloys. The following article describes the particular demands ruled by legislation on building pro-ducts, just as the consequences resulting from corrosion loads by flue gas condensates. Difficulties caused by manufacturing and construction are primarily discussed. Furthermore a test procedure is introduced that allows to catch and correlate corrosion loads and technical designs systematically to corrosion behaviour and service life of flue gas devices. For the first time a tool for active quality assurance has been given by this test rig allowing to recognize construction errors systematically. This way, manufacturers of system chimneys and flue liners are enabled to optimize their products applications going ahead to the respective requests of the market. (authors)

  15. Hydrothermal carbonate chimneys from a continental rift (Afar Rift): Mineralogy, geochemistry, and mode of formation

    OpenAIRE

    Dekov, V. M.; Egueh, N. M.; Kamenov, G.D.; Bayon, G.; Lalonde, S. V.; Schmidt, Mark; Liebetrau, Volker; Munnik, F.; Fouquet, Y.; Tanimizu, M.; Awaleh, M. O.; Guirreh, I.; Le Gall, B.

    2014-01-01

    International audience Carbonate chimney-like deposits up to 60 m high are scattered or arranged in rows at the shores of a desiccating hypersaline and alkaline lake from a continental rift setting (Lake Abhé, Afar Rift, Djibouti). The chimneys formed sub-aqueously in the lake water body at a higher water level than observed today. Alternating calcite and low-Mg calcite + silica concentric layers compose the chimney structures. Mineralogical and geochemical investigations of the chimneys, ...

  16. The contribution of trace elements from seawater to chimneys: a case study of the native sulfur chimneys in the sea area off Kueishantao, northeast of Taiwan Island

    Institute of Scientific and Technical Information of China (English)

    LIU Changhua; WANG Xiaomei; JIN Xindi; ZENG Zhigang; CHEN Chentung A.

    2009-01-01

    Hydrothermal fluid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid from deep reservoir. However, because of seawater's little contribution to the forming of chimneys, it is usually covered by the abundant matter which is taken by hydrothermal fluid. Therefore, chimneys formed in ordinary deep seawater hydrothermal activity, containing complex elements, cannot be used to study the seawater's contribution to their formation. While the native sulfur chimneys, formed by hydrothermal activity near the sea area off Kueishantao, are single sulfur composition (over 99%), and within chimneys distinct layers are seen. Different layers were sampled for trace element determination, with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). By analyzing the data, we consider C-layer (secondary inner-layer) as the framework layer of the chimney which formed early (Fig.4), and its trace elements derive from hydrothermal fluid. While the trace elements within A, B, D layers have undergone later alteration. A, B layers are affected by seawater and D layer by hydrothermal fluid. The increase of trace elements of A and B layers was calculated using C layer as background. Based on the known typical volume of chimneys of the near sea area off Kueishantao, we calculated the volume of seawater that contributed trace element to chimneys formation to be about 6.37×104 L. This simple quantified estimate may help us better understand the seafloor hydrothermal activity and chimneys.

  17. A performance analysis of solar chimney thermal power systems

    Directory of Open Access Journals (Sweden)

    Al-Dabbas Awwad Mohammed

    2011-01-01

    Full Text Available The objective of this study was to evaluate the solar chimney performance theoretically (techno-economic. A mathematical model was developed to estimate the following parameter: Power output, Pressure drop across the turbine, the max chimney height, Airflow temperature, and the overall efficiency of solar chimney. The mathematical model was validated with experimental data from the prototype in Manzanares power. It can be concluded that the differential pressure of collector-chimney transition section in the system, is increase with the increase of solar radiation intensity. The specific system costs are between 2000 Eur/kW and 5000 Eur/kW depending on the system size, system concept and storage size. Hence, a 50 MWe solar thermal power plant will cost 100-250 Eur million. At very good sites, today’s solar thermal power plants can generate electricity in the range of 0.15 Eur/kWh, and series production could soon bring down these costs below 0.10 Eur /kWh.

  18. The impact of the combined chimney outlet size and extended solar wall-roof chimney on airflow patterns using numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    AboulNaga, M.M.; Alteraifi, A.M.

    1999-07-01

    This paper investigates airflow patterns and behavior of combined roof and extended solar wall-roof chimney incorporated into a typical room with an inlet and outlet. Numerical simulations using the Fluid Dynamics software Package, FIDAP, are exploited to describe and analyze the airflow patterns inside the room, and in the extended solar wall-roof chimneys. FIDAP simulation analyses and results of the airflow streamline, velocity vectors, and temperature distributions are presented. Maximum velocity vector, temperatures, and smooth streamlines were found for better performance at separation of 0.25m. At 0.25m separation, in both wall and roof solar chimneys, the maximum chimney outlet flow rate and smooth streamline were found when the wall chimney is 2.00m high, which corresponds to a wall chimney inlet of 1.60m. Results show that the maximum relative speed in the combined chimneys is higher than the solar roof chimney alone. These findings suggest that the exploitation of an extended solar roof-wall chimney could enhance nighttime natural ventilation and the cooling of buildings. The system is limited to cool low-rise buildings in hot-arid regions such as Al-Ain City, UAE, where energy use is enormous.

  19. The computational optimization of heat exchange efficiency in stack chimneys

    Energy Technology Data Exchange (ETDEWEB)

    Van Goch, T.A.J.

    2012-02-15

    For many industrial processes, the chimney is the final step before hot fumes, with high thermal energy content, are discharged into the atmosphere. Tapping into this energy and utilizing it for heating or cooling applications, could improve sustainability, efficiency and/or reduce operational costs. Alternatively, an unused chimney, like the monumental chimney at the Eindhoven University of Technology, could serve as an 'energy channeler' once more; it can enhance free cooling by exploiting the stack effect. This study aims to identify design parameters that influence annual heat exchange in such stack chimney applications and optimize these parameters for specific scenarios to maximize the performance. Performance is defined by annual heat exchange, system efficiency and costs. The energy required for the water pump as compared to the energy exchanged, defines the system efficiency, which is expressed in an efficiency coefficient (EC). This study is an example of applying building performance simulation (BPS) tools for decision support in the early phase of the design process. In this study, BPS tools are used to provide design guidance, performance evaluation and optimization. A general method for optimization of simulation models will be studied, and applied in two case studies with different applications (heating/cooling), namely; (1) CERES case: 'Eindhoven University of Technology monumental stack chimney equipped with a heat exchanger, rejects heat to load the cold source of the aquifer system on the campus of the university and/or provides free cooling to the CERES building'; and (2) Industrial case: 'Heat exchanger in an industrial stack chimney, which recoups heat for use in e.g. absorption cooling'. The main research question, addressing the concerns of both cases, is expressed as follows: 'what is the optimal set of design parameters so heat exchange in stack chimneys is optimized annually for the cases in which a

  20. Formation of Chimneys in Mushy Layers: Experiment and Simulation

    CERN Document Server

    Anderson, Anthony M; Worster, Grae

    2011-01-01

    In this fluid dyanmics video, we show experimental images and simulations of chimney formation in mushy layers. A directional solidification apparatus was used to freeze 25 wt % aqueous ammonium chloride solutions at controlled rates in a narrow Hele-Shaw cell (1mm gap). The convective motion is imaged with schlieren. We demonstrate the ability to numerically simulate mushy layer growth for direct comparison with experiments.

  1. Power generation from wind turbines in a solar chimney

    Energy Technology Data Exchange (ETDEWEB)

    Foote, Tudor [Graduate Student, Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Jolley Hall, Campus Box 1185, One Brookings Drive, St. Louis, Missouri, 63130 (United States); Agarwal, Ramesh K. [William Palm Professor, Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Jolley Hall, Campus Box 1185, One Brookings Drive, St. Louis, Missouri, 63130 (United States)

    2013-07-01

    Recent studies have shown that shrouded wind turbines can generate greater power compared to bare turbines. A solar chimney generates an upward draft of wind inside a tower and a shroud around the wind turbine. There are numerous empty silos on farms in the U.S. that can be converted to solar chimneys with minor modifications at modest cost. The objective of this study is to determine the potential of these silos/chimneys for generating wind power. The study is conducted through analytical/computational approach by employing the commercial Computational Fluid Dynamics (CFD) software. Computations are performed for five different geometric configurations consisting of a turbine, a cylindrical silo, and/or a venturi and/or a diffuser using the dimensions of typical silos and assuming Class 3 wind velocity. The incompressible Navier-Stokes equations with the Boussinesq approximation and a two equation realizable {kappa}-{epsilon} model are employed in the calculations, and the turbine is modeled as an actuator disk. The power coefficient (Cp) and generated power are calculated for the five cases. Consistent with recent literature, it was found that the silos with diffusers increase the Cp beyond Betz’s limit significantly and thus the generated power. It should be noted that Cp is calculated by normalizing it by the turbine area swept by the wind. This study shows the potential of using abandoned silos in the mid-west and other parts of the country for localized wind power generation.

  2. GEOCHEMICAL CHARACTERISTICS OF STABLE ISOTOPES FROM HYDROTHERMAL CHIMNEYS IN THE MARIANA TROUGH, WEST PACIFIC OCEAN

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The determination of the stable isotopes, δD, δ18O and δ30Si, values from hydrothermal chimneys in the Mariana Trough, the West Pacific, indicated that the pure siliceous chimneys with gentle data variation were formed in low temperature environment. It reflects that the sea-floor hydrothermal activity of the Mariana Trough is primarily low-to-medium temperature hydrothermal eruption, and those chimneys with strong data variation and containing pyrite were formed in higher temperature environment.

  3. Improvement of the Vertical Dispersion of Pollutants Resulting From Chimneys by Thermosiphon Effect

    OpenAIRE

    A. O.M. Mahmoud; J. Zinoubi; R.B. Maad; A. Belghith

    2006-01-01

    The dispersion of pollutants, resulting from industrial chimneys, in the surrounding atmosphere made the interest in realizing emitting conditions appears. It also encourages the vertical dispersion of these pollutants. At a given wind velocity, the height of this dispersion is essentially a function of the thermal power and the flow rate at the chimney exit. To improve these qualities, we propose a system that could be integrated to the industrial chimney exit. An open-ended vertical cylinde...

  4. Solar chimney design: Investigating natural ventilation and cooling in offices with the aid of computer simulation

    Science.gov (United States)

    Angelis, Nikolaos

    Solar chimney design is investigated as a means of improving natural ventilation and passive cooling in office buildings. Existing scientific research and built precedents are generally limited literature review findings on various features of solar chimneys were categorised and used to develop a building simulation strategy. Using UK climatic data, simulations were performed on several computer models in order to investigate solar chimney performance during a single day period and an entire cooling season. Passive cooling with a solar chimney is possible but actual reduction in temperatures in most cases examined could be negligible. Cooling potential is increased on still, warm days, while the prospects for night cooling are further improved. A solar chimney may help reduce considerably the occurrence of resultant temperatures at or above the 25 C and 28 C thresholds. Solar chimney width, height, apertures and integral use of thermal mass are the most significant parameters for cooling. Simulation results showed that a solar chimney can increase significantly natural ventilation rates. Total ventilation rates may be increased by at least 22%. During still days a solar chimney can enhance ventilation rates by 36% or more. Stack ventilation through a solar chimney is typically 20% of cross ventilation during night time this may increase to at least 40-45% and on still days it may reach 100% of typical cross ventilation rates. Solar chimney induced stack ventilation and cross ventilation are interrelated. Resultant air flow patterns may have an important effect on convective heat transfers and thermal comfort. Climate and microclimate conditions should be an integral part of solar chimney design. Key aspects and recommendations regarding solar chimneys, passive cooling and natural ventilation are provided for design guidance and feedback in further research.

  5. Growth history of hydrothermal chimneys at EPR 9―10°N: A structural and mineralogical study

    Institute of Scientific and Technical Information of China (English)

    PENG Xiaotong; ZHOU Huaiyang

    2005-01-01

    Based on structural and mineralogical characteristics of four hydrothermal chimney samples collected by submersible Alvin, growth history and formation environment of hydrothermal chimney at EPR 9―10°N are established. It is shown that there occur two types of hydrothermal chimney with different deposition environments at EPR 9―10°N according to differences in their shape, structure and mineral assemblage: type I chimney forms in an environment with high temperature, low pH and strong reducing hydrothermal focus flow and type II chimney forms in a relatively low temperature, high pH and rich Zn hydrothermal environment. Growth of type I chimney begins with the formation of anhydrite. Subsequently deposition of Cu-Fe-Zn sulphide in various directions of chimneys decides the final structure of this type of chimney. According to observation and analysis of mineral assemblages, the formation process of type I chimney could be divided into three stages from early, middle to late. Changes of temperature and major chemical reaction type in the process of hydrothermal chimney formation are also deduced. Different from type I chimney, quenching crystalline of pyrite and/or crystalline of sphalerite provide the growth foundation of type II chimney in the early stage of chimney formation.

  6. Solar ventilation: The use of solar chimneys for natural ventilation of buildings

    NARCIS (Netherlands)

    Macquoy, B.

    2011-01-01

    This paper is written for the TIDO-course AR0532 Smart & Bioclimatic Design Theory. A very old principle is the system of the solar chimney for ventilation, which in recent years has regained interests. This essay will explore the potentials of solar chimneys in a modern application.

  7. Methane seepage in the Shenhu area of the northern South China Sea: constraints from carbonate chimneys

    Science.gov (United States)

    Guan, Hongxiang; Zhang, Mei; Mao, Shengyi; Wu, Nengyou; Lu, Hongfeng; Chen, Duofu

    2016-06-01

    Two authigenic carbonate chimneys were recovered from the Shenhu area in the northern South China Sea at approximately 400 m water depth. The chimneys' mineralogy, isotopic composition, and lipid biomarkers were studied to examine the biogeochemical process that induced the formation of the chimneys. The two chimneys are composed mostly of dolomite, whereas the internal conduits and semi-consolidated surrounding sediments are dominated by aragonite and calcite. The specific biomarker patterns (distribution of lipids and their depleted δ13C values) indicate the low occurrence of methanotrophic archaea ANME-1 responsible for the chimneys' formation via anaerobic oxidation of methane. A significant input of bacteria/planktonic algae and cyanobacteria to the carbon pool during the precipitation of the carbonate chimneys is suggested by the high contributions of short-chain n-alkanes (69% of total hydrocarbons) and long-chain n-alcohols (on average 56% of total alcohols). The oxygen isotopic compositions of the carbonate mixtures vary from 3.1‰ to 4.4‰ in the dolomite-rich chimneys, and from 2.1‰ to 2.5‰ in the internal conduits, which indicates that they were precipitated from seawater-derived pore waters during a long period covering the last glacial and interglacial cycles. In addition, the mixture of methane and bottom seawater dissolved inorganic carbon could be the carbon sources of the carbonate chimneys.

  8. Tree cavity use by Chimney Swifts: implications for forestry and population recovery

    Directory of Open Access Journals (Sweden)

    Carolyn Zanchetta

    2014-12-01

    Full Text Available The Chimney Swift (Chaetura pelagica is an aerial insectivore and a cavity-nesting/roosting specialist designated as threatened in several jurisdictions. As the occurrence of suitable chimneys declines, Chimney Swifts may increasingly nest and roost in tree cavities. It is therefore important to identify characteristics of suitable nest or roost trees and assess their frequency of occurrence. We reviewed 59 historic and modern records of trees used by Chimney Swifts to understand characteristics of suitable nest or roost trees. Chimney Swifts used at least 13 different deciduous and coniferous tree species. All of the trees were greater than 0.5 m diameter at breast height (DBH and were described as hollow or having cavities. Nest or roost tree height was 12.7 ± 7.0 m (mean ± SD; range: 3.6-28.0 m; n = 25 and DBH was 1.0 m ± 0.5 m (range 0.5-2.1 m; n = 21. According to our description of used trees, the number of suitably hollow Chimney Swift nest or roost trees may be two to three times higher, although still rare, in most unlogged compared to logged hardwood forests. Whether the current total supply of suitable nest or roost trees is sufficient to carry the anticipated increase in use by Chimney Swifts as chimney habitat is modified or deteriorates is unknown. Monitoring the frequency of use of tree cavities by nesting and roosting Chimney Swifts over time, and more robustly quantifying the availability of suitable tree cavities in different forest types for nesting and roosting Chimney Swifts, particularly in unlogged versus logged forests, are fruitful areas for future research.

  9. Effect of solar chimney inclination angle on space flow pattern and ventilation rate

    Energy Technology Data Exchange (ETDEWEB)

    Bassiouny, Ramadan; Korah, Nader S.A. [Department of Mechanical Power Engineering and Energy, Minia University, Minia 61111 (Egypt)

    2009-02-15

    The solar chimney is a simple and practical idea that is applied to enhance space natural ventilation. The chimney could be vertical or inclined. The chimney inclination angle is an important parameter that greatly affects space flow pattern and ventilation rate. In the present study, the effect of chimney inclination angle on air change per hour and indoor flow pattern was numerically and analytically investigated. A numerical simulation using Ansys, a FEM-based code, was used to predict flow pattern. Then the results were compared with published experimental measurements. A FORTRAN program was developed to iteratively solve the mathematical model that was obtained through an overall energy balance on the solar chimney. The analytical results showed that an optimum air flow rate value was achieved when the chimney inclination is between 45 and 70 for latitude of 28.4 . The numerically predicted flow pattern inside the space supports this finding. Moreover, in the present study a correlation to predict the air change per hour was developed. The correlation was tested within a solar intensity greater than or equal to 500 W/m{sup 2}, and chimney width from 0.1 m to 0.35 m for different inclination angles with acceptable values. (author)

  10. Full scale monitoring of the twin chimneys of the rovinari power plant

    Directory of Open Access Journals (Sweden)

    Bayati I.

    2015-01-01

    Full Text Available The presented paper deals with the structural identification and monitoring of two twin chimneys in very close arrangement. Due to twin arrangement, important interference effects are expected to modify the chimney response to wind action, causing vortex shedding and state-dependent excitation associated to the oscillatory motion of the leeward chimney, in and out of the windward chimney wake. The complexity of the physics of this problem is increased by the dependency of the aerodynamics of circular cylinders on Reynolds number; however, there is a weakness of literature about cylinders behaviour at critical and super-critical range of Reynolds number, due to experimental limitations. Also the International Committee on Industrial Chimneys (CICIND does not provide, at present, any specific technical guideline about twin chimneys whose interaxis distance is less or equal two times the diameter, as in this case. For this reason a Tuned Mass Damper (TMD has been installed in order to increase the damping of the chimney, as merely suggested. This work aims at assessing the effectiveness of the installed TMD and characterizing the tower dynamic behaviour itself due to the wind excitation, as well as providing full scale measurements for twin cylinders configuration at high Reynolds numbers.

  11. ChEVAS: Combining Suprarenal EVAS with Chimney Technique

    Energy Technology Data Exchange (ETDEWEB)

    Torella, Francesco, E-mail: f.torella@liverpool.ac.uk [Royal Liverpool University Hospital, Liverpool Vascular & Endovascular Service (United Kingdom); Chan, Tze Y., E-mail: tze.chan@rlbuht.nhs.uk; Shaikh, Usman, E-mail: usman.shaikh@rlbuht.nhs.uk [Royal Liverpool University Hospital, Department of Radiology (United Kingdom); England, Andrew, E-mail: a.england@salford.ac.uk [University of Salford, Department of Radiography (United Kingdom); Fisher, Robert K., E-mail: robert.fisher@rlbuht.nhs.uk [Royal Liverpool University Hospital, Liverpool Vascular & Endovascular Service (United Kingdom); McWilliams, Richard G., E-mail: richard.mcwilliams@rlbuht.nhs.uk [Royal Liverpool University Hospital, Department of Radiology (United Kingdom)

    2015-10-15

    Endovascular sealing with the Nellix{sup ®} endoprosthesis (EVAS) is a new technique to treat infrarenal abdominal aortic aneurysms. We describe the use of endovascular sealing in conjunction with chimney stents for the renal arteries (chEVAS) in two patients, one with a refractory type Ia endoleak and an expanding aneurysm, and one with a large juxtarenal aneurysm unsuitable for fenestrated endovascular repair (EVAR). Both aneurysms were successfully excluded. Our report confirms the utility of chEVAS in challenging cases, where suprarenal seal is necessary. We suggest that, due to lack of knowledge on its durability, chEVAS should only been considered when more conventional treatment modalities (open repair and fenestrated EVAR) are deemed difficult or unfeasible.

  12. Chimney Effect Assessment of the Double-skin Facade

    Institute of Scientific and Technical Information of China (English)

    QIU Zhong-zhu; LI Peng; CHOW Tin-tai; REN Jian-xing; WANG Wen-huan

    2009-01-01

    The mathematic model of heat transfer through ventihted double glazing was verified with themeasured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and wind speed measurement facility.Mter the model validation,the double-skin facade assess-ment was carried out through simulation with ESP-r software integrating thermal simulation and air low net work module.The air flow situation in the air gap was analyzed on the basis of the hourly air velocity simulation data within typical winter week,summer week,spring week and autumn week.The differences of chimney ef-fect in different seasons were discussed,and the thermal loads resulted from the ventilated and unventihted dou-ble skin facade were presented.

  13. ChEVAS: Combining Suprarenal EVAS with Chimney Technique

    International Nuclear Information System (INIS)

    Endovascular sealing with the Nellix® endoprosthesis (EVAS) is a new technique to treat infrarenal abdominal aortic aneurysms. We describe the use of endovascular sealing in conjunction with chimney stents for the renal arteries (chEVAS) in two patients, one with a refractory type Ia endoleak and an expanding aneurysm, and one with a large juxtarenal aneurysm unsuitable for fenestrated endovascular repair (EVAR). Both aneurysms were successfully excluded. Our report confirms the utility of chEVAS in challenging cases, where suprarenal seal is necessary. We suggest that, due to lack of knowledge on its durability, chEVAS should only been considered when more conventional treatment modalities (open repair and fenestrated EVAR) are deemed difficult or unfeasible

  14. Marketable solar chimney passive solar system components: research and development

    Energy Technology Data Exchange (ETDEWEB)

    De Pascali, P.; Andreotti, P.; Scudo, G.; Silingardi, A.; Gabbi, L.; Grasselli, C.; Cattivelli, F.; Farruggia, S.; Giannotti, A.M. (Ist. Cooperativo per l' Innovazione, Rome (Italy); Milan Politecnico (Italy); Coopsette scrl, Castelnovo Sotto (Italy))

    1989-02-01

    The report describes research to develop a marketable passive solar system incorporating a solar chimney in which heated air rises and produces a natural convection air flow within a double envelope construction. The equipment consists of a heat capturing element, another element to distribute and accumulate heat and a control system. Research activities involved: the study of feasible configurations and performance requirements; the design of a selected configuration; a computerized simulation of the system; and the development of two prototype modules to be lab tested at a facility equipped with real time data acquisition systems. The coordinated effort strove to obtain a multi-use system capable of providing summer cooling, as well as, winter heating and a system which would be accepted by both the construction industry and potential home buyers.

  15. Finite Element Analysis and Linear Regression of Maximum Temperature for Inner Wall of Chimney Foundation

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The uniform design method was adopted and the twenty-four groups of different geometric and physical parameters were chosen. The finite element model was built. Comparisons between the simulation results and the test results prove that the simulation results are correct. The distribution of the temperature field of the chimney foundation was analyzed. The multivariate linear regression of the hightest tomperature was performed on the inner wall of the chimney foundation by the numerical calculated results. The fitting property of the highest temperature with six influence factors was obtained. A simple method for the calculation of the temperature field of the chimney foundation was provided.

  16. Modeling microbial reaction rates in a submarine hydrothermal vent chimney wall

    NARCIS (Netherlands)

    LaRowe, D.E.; Dale, A.W.; Aguilera, D.R.; L'Heureux, I.; Amend, J.P.; Regnier, P.

    2014-01-01

    The fluids emanating from active submarine hydrothermal vent chimneys provide a window into subseafloor processes and, through mixing with seawater, are responsible for steep thermal and compositional gradients that provide the energetic basis for diverse biological communities. Although several mod

  17. Analytical study of the closure flow inside the ETRR-2 core chimney

    Energy Technology Data Exchange (ETDEWEB)

    El-Din El-Morshdy, S. [Atomic Energy Authority, Cairo (Egypt). Reactors Dept.

    2006-12-15

    The present work is carried out in order to study the closure flow inside the core chimney of the Egypt second research reactor (ETRR-2). Based on the finite difference technique, a two dimensional model is developed to simulate the coolant flow inside the chimney. The model is verified by FEHT finite element program. Then a study of different closure flow values inside the chimney was made using the developed model where a flow map is plotted showing the stagnation depth for each closure flow. The flow map shows that for a closure flow greater than 0.16 m{sup 3}/h, no active water ascends from the core to the pool through the chimney. The model results are analyzed and discussed. (orig.)

  18. Analytical study of the closure flow inside the ETRR-2 core chimney

    Energy Technology Data Exchange (ETDEWEB)

    El-Morshdy, Salah El-Din [Reactors Department, Atomic Energy Authority, Cairo (Egypt)]. E-mail: selmorshedy@etrr2-aea.org.eg

    2007-03-15

    The present work is carried out in order to study the closure flow inside the core chimney of the Egypt second research reactor (ETRR-2). Based on the finite difference technique, a two dimensional model is developed to simulate the coolant flow inside the chimney. The model is verified by FEHT finite element program. Then a study of different closure flow values inside the chimney was made using the developed model where a flow maps is plotted showing the stagnation depth for each closure flow. The flow maps shows that for a closure flow greater than 0.16 m{sup 3}/h, no radioactive water ascends from the core to the pool through the chimney. The model results are analyzed and discussed.

  19. Modelling and simulation of condensation phenomena of acid gases in an industrial chimney

    OpenAIRE

    Serris, Eric; Cournil, Michel; Peultier, Jérôme

    2007-01-01

    Coal power stations as well as waste incinerators produce humid acid gases which condensate in industrial chimneys. These condensates may cause corrosion of the internal cladding made of stainless steels, nickel base alloys or non metallic materials. In the aim of polluting emission reduction and material optimal choice, it is necessary to determine all the phenomena which occur throughout the chimney such as condensation and dissolution of acid gases (in this particular case, sulphur dioxide...

  20. Basement Kind Effects on Air Temperature of a Solar Chimney in Baghdad - Iraq Weather

    OpenAIRE

    Miqdam Tariq Chaichan

    2011-01-01

    A solar updraft tower power plant (solar tower) is a solar thermal power plant that utilizes a combination of solar air collector and central updraft tube to generate an induced convective flow which drives pressure staged turbines to generate electricity. This paper presents practical results of a prototype of a solar chimney with thermal mass, where the glass surface is replaced by transparence plastic cover. The study focused on chimney's basements kind effect on collected air temperatur...

  1. The Balkan Theme in The Secret of Chimneys

    Directory of Open Access Journals (Sweden)

    Graham St. John Stott

    2016-06-01

    Full Text Available In The Secret of Chimneys (1925 Agatha Christie uses the all too familiar Balkan stereotypes of backwardness and brigandage, but not – as was usually the case at the time – as an Other to illustrate British virtue, but as a mirror to British vice. It is Britain, not the fictional Herzoslovakia, that is a nation of brigands. Herzoslovakia remains relatively unknown, as none of the novel’s scenes take place there, but it is described by disinterested observers as democratic and prosperous. In London, however, the Foreign Office plans to overthrow its government to secure oil rights promised by a royal heir-in-exile to a London-based financial consortium. Keywords: Christie, Balkans, Romania, oil, brigandsAgatha Christie’s The Secret of Chimneys (1925 has been faulted for being on the one hand a frothy mix of Anthony Hope and P. G. Wodehouse (Thompson 143 and on the other a mishmash of popular ethnic, national and regional stereotypes – including those of the Balkans (Todorova 122. It is, however, a far more subtle work than such accounts suggest. Though the influence of Hope and Wodehouse can certainly be seen in the novel’s story of princes in disguise (reminiscent of The Prisoner of Zenda and a country house setting that would have reminded readers of Blandings, its main plot addresses an important theme –and in exploring it Christie takes the Balkans very seriously. Oil has been found in the Republic of Herzoslovakia and the Foreign Office, represented by George Lomax, has secured the pledge of the exiled Prince Michael Obolovitch “to grant certain oil concessions” to a consortium led by Herman Isaacstein if the Obolovitchs are restored to power. In other words: to secure those concessions the British Government has committed itself to the overthrow of Herzoslovakia’s government. The Foreign Office’s interest in the Balkans might not have surprised Christie’s readers. The Anglo-Iranian Oil Company had held a monopoly on

  2. Effect of cold inflow on chimney height of natural draft cooling towers

    International Nuclear Information System (INIS)

    Highlights: ► Natural convection data were obtained from an air-cooled heat exchanger model. ► The extent of cold inflow was quantified to relate to the decrease in effective chimney height. ► Installation of wire mesh screen on chimney outlet blocked off cold inflow to improve the chimney efficiency. ► Evidence of existence of effective plume-chimney for when cold inflow was blocked off warrants further work. - Abstract: Temperature and pressure drop data obtained from an air-cooled heat exchanger model with cross-sectional flow areas of 0.56 m2, 1.00 m2 and 2.25 m2 operating under natural convection are presented that indicate significant cold inflow, resulting in the reduction of effective chimney height. Cold inflows encountered in actual applications where the Froude number is typically 0.2, may not be as severe as described in this paper, which was of the order of 10−6–10−4. Additional tests on smaller scale models appeared to favor the explanation that the occurrence of cold inflow in the air-cooled heat exchanger model was primarily due to the relative ease in either drawing cold air from inlet or from outlet, and to a lesser extent the Froude number of the chimney or the critical velocity estimated by formula. A CFD study will bring much understanding of the phenomenon for the different situations.

  3. Modeling and characteristics analysis of hybrid cooling-tower-solar-chimney system

    International Nuclear Information System (INIS)

    Highlights: • A 3-D model for hybrid cooling-tower-solar-chimney system is developed. • The inclusion of heat exchangers into solar chimney boosts the power output. • The huge jump in power output is at the expense of heat dissipation capacity. • The heat exchanger as second heat source has greater impact on system performance. - Abstract: The hybrid cooling-tower-solar-chimney system (HCTSC), combining solar chimney with natural draft dry cooling tower, generates electricity and dissipates waste heat for the coupled geothermal power plant simultaneously. Based on a developed 3-D model, performance comparisons between the HCTSC system, solar chimney and natural draft dry cooling tower were performed in terms of power output of turbine and heat dissipation capacity. Results show that compared to the traditional solar chimney with similar geometric dimensions, HCTSC system can achieve over 20 times increase in the power output of turbine. However, this huge jump in power output is at the expense of heat dissipation capacity, which may lead to the malfunction of the coupled thermal power plant. By increasing the heat transfer area of the heat exchanger, the HCTSC system can manage to recover its heat dissipation capacity

  4. Experimental study of the resulting flow of plume-thermosiphon interaction: application to chimney problems

    Energy Technology Data Exchange (ETDEWEB)

    Zinoubi, J.; Maad, R.B.; Belghith, A. [Faculte des Sciences de Tunis, Tunis (Tunisia). Departement de Physique, Laboratoire d' Energetique et des Transferts de Chaleur et de Masse

    2005-03-01

    The quality of the surrounding air depends on the various dismissals of the combustion gases (exhaust cars, smokes of chimneys, ...), their scattering in the environment. Urban development around industrial zones and overexploitation of lands near factories triggered responsible interest in the problem of pollution. In order to decrease the impact of air pollution, several chimneys have been constructed in the different industrial facilities. So the improvement of the industrial chimney range became one of the current research problems. In order to improve the industrial chimney efficiency and to increase the vertical scattering of combustion products, we studied a system that could be integrated to the industrial chimney exit. This system is essentially constituted of an open-ended vertical cylinder of larger diameter. Thermal radiance emitted by smoke heats the internal cylinder wall. The heating of the fluid at the cylinder-inlet is the cause of the thermosiphon effect around the thermal plume. To study the problem in the laboratory we simulated the plume exiting of a chimney by a disk heated uniformly by the Joule effect at constant temperature. Different configurations were studied, while acting, on the source-cylinder spacing and the cylinder height. The study of the average fields permits, in a first stage, to get better information about the mechanism of the resulting flow development, and in a second stage, to determine the spacing of the source-cylinder and cylinder height optima, for which a clean increase of fluid flow rate is obtained. (author)

  5. Development of the lined masonry chimney oil appliance

    Energy Technology Data Exchange (ETDEWEB)

    Krajewski, R.; Strasser, J. [Brookhaven National Lab., Upton, NY (United States)

    1996-07-01

    This paper describes the development of the lined masonry chimney venting tables form the output of the Oil Heat Analysis Program 9OHVAP. These new tables are different from the prior format, offered in the Proceedings of the 1995 Oil Heat Technology Conference and Workshop, paper No. 95-4. Issues expressed by representatives of the oil heat industry at last years conference during the Venting Technology Workshop resulted in subsequent discussions. A full day meeting was held, co-sponsored by BNL and the Oilheat Manufacturers Association (OMA), to address revision of the format of the venting tables prior to submission to the National Fire Protection Association (NFPA) Standard 31 Technical Committee. The resulting tables and text were submitted to NFPA during the first week of October, 1995. Since then minor changes were made reflecting the addition of data obtained by including intermediate firing rates (0.4, 0.65, and 0.85 gph) not included in the original tables which were developed in increments of 0.25 gph. The new tables address the specific question; {open_quotes}If remediation is required, what is the recommendation for the sizing of a metal liner and the appropriate firing rate range to be used with that liner?{close_quotes}

  6. Beautiful heat: a master chimney sweep talks about burning issues

    Energy Technology Data Exchange (ETDEWEB)

    Hederich, M.P.

    2001-07-01

    Fire has played a major role in mankind's life from the beginning. Used for heating and cooking, its various uses have evolved to include controlled explosions shortly after the development of gunpowder, and the generation of electricity made other uses possible. The author, a certified solid fuel technician and chimney sweep, as well as a licensed technician for natural gas and propane, has written this book to enable the reader to enjoy safe and dependable wood fires year round by taking the necessary steps. The first recommendation made is against the homeowner installing himself/herself any solid fuel system. It is a job better left to the professionals, considering the substantial product and regulation knowledge and experience required. Specific information related to solid fuel burning technology is included in this book, to be used as a guide. Part 1 of the book deals with the fuel, touching on issues such as energy and the environment, wood combustion and air pollution, buying firewood, wood ashes, cleaning your heating system and others. Part 2 is devoted to the heating system. It introduces topics ranging from the systems advisor to the location and installation of the system, the principles of space heating, high efficiency wood burning, inspections, to name just a few. 22 refs., tabs., figs.

  7. Metagenome reveals potential microbial degradation of hydrocarbon coupled with sulfate reduction in an oil-immersed chimney from Guaymas Basin

    Directory of Open Access Journals (Sweden)

    Ying eHe

    2013-06-01

    Full Text Available Deep-sea hydrothermal vent chimneys contain a high diversity of microorganisms, yet the metabolic activity and the ecological functions of the microbial communities remain largely unexplored. In this study, a metagenomic approach was applied to characterize the metabolic potential in a Guaymas hydrothermal vent chimney and to conduct comparative genomic analysis among a variety of environments with sequenced metagenomes. Complete clustering of functional gene categories with a comparative metagenomic approach showed that this Guaymas chimney metagenome was clustered most closely with a chimney metagenome from Juan de Fuca. All chimney samples were enriched with genes involved in recombination and repair, chemotaxis and flagellar assembly, highlighting their roles in coping with the fluctuating extreme deep-sea environments. A high proportion of transposases was observed in all the metagenomes from deep-sea chimneys, supporting the previous hypothesis that horizontal gene transfer may be common in the deep-sea vent chimney biosphere. In the Guaymas chimney metagenome, thermophilic sulfate reducing microorganisms including bacteria and archaea were found predominant, and genes coding for the degradation of refractory organic compounds such as cellulose, lipid, pullullan, as well as a few hydrocarbons including toluene, ethylbenzene and o-xylene were identified. Therefore, this oil-immersed chimney supported a thermophilic microbial community capable of oxidizing a range of hydrocarbons that served as electron donors for sulphate reduction under anaerobic conditions.

  8. Mineralization of a Proterozoic Sulfide Black Smoker Chimney and Thermophilous Microorganisms in Eastern Hebei, China

    Institute of Scientific and Technical Information of China (English)

    XIA Xuehui; LIAN Wei; YUAN Congjian; YAN Fei; YUAN Jiazhong

    2008-01-01

    A sulfide black smoker chimney exists in the Gaobanhe seabed exhalation massive sulfidedeposit in the Xinglong-Kuancheng secondary fault basin of the Proterozoic Yanliao rift trough inHebei Province, taking the shape of mounds, individually about 2-3 cm high. Abundant fossils ofthermophilous bacteria and algae in perfect preservation are found in the ore surrounding the blacksmoker chimney. Scanning electron microscopy (SEM) and molecular biomarker studies on themicroorganismal ore fabric show that the microorganism in the sulfide ore is in fact a sedimentaryproduct of probiotic bacteria and algae. In the special food chain based on black smoker chimney atancient seabed- thermophilous bacteria, the thermophilons bacteria and algae reproduce in largequantity. Intermittently erupting of fluid from the chimney creats conditions for formation of sulfidedeposit. In the process of exhalation action of hot fluid, thermophilous bacteria and algae grow andreproduce around the sulfide black smoker chimney, absorbing mineralizing substances brought bythe fluid. Massive sulfide deposits are formed in this process of absorption of seabed black smokerchimney exhalation-mineralizing fluid puisation.thermophilous microorganism.

  9. An analytical and numerical study of solar chimney use for room natural ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Bassiouny, Ramadan; Koura, Nader S.A. [Department of Mechanical Power Engineering and Energy, Minia University, Minia 61111 (Egypt)

    2008-07-01

    The solar chimney concept used for improving room natural ventilation was analytically and numerically studied. The study considered some geometrical parameters such as chimney inlet size and width, which are believed to have a significant effect on space ventilation. The numerical analysis was intended to predict the flow pattern in the room as well as in the chimney. This would help optimizing design parameters. The results were compared with available published experimental and theoretical data. There was an acceptable trend match between the present analytical results and the published data for the room air change per hour, ACH. Further, it was noticed that the chimney width has a more significant effect on ACH compared to the chimney inlet size. The results showed that the absorber average temperature could be correlated to the intensity as: (T{sub w} = 3.51I{sup 0.461}) with an accepted range of approximation error. In addition the average air exit velocity was found to vary with the intensity as ({nu}{sub ex} = 0.013I{sup 0.4}). (author)

  10. Numerical simulation of turbulent flow mixing inside a square chimney structure of a research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, S.; Bhatnagar, A. [Bhabha Atomic Research Centre, Mumbai (India). Research Reactor Design and Projects Div.; Vijayan, P.K. [Bhabha Atomic Research Centre, Mumbai (India). Reactor Engineering Div.; Singh, R.K. [Bhabha Atomic Research Centre, Mumbai (India). Reactor Safety Div.; Raina, V.K. [Bhabha Atomic Research Centre, Mumbai (India). Reactor Group

    2013-11-15

    Numerical simulation was performed to study the turbulent mixing behavior of two opposing flows inside a square chimney structure of a research reactor. The chimney design facilitates drawing pool water in the downward direction and thereby suppresses the upward flow of radioactive water jet to limit the radiation field at the reactor pool top. Analyses were carried out considering a mass flow rate of 750 kg/s for the upward flowing hot water from the core, which corresponds to Reynolds number of 3 x 10{sup 6}. Mass flow ratios of the downward flow and the upward flow were 0.0, 0.05, 0.1 and 0.15. The effects of mass flow ratio, chimney height on the velocity and temperature distribution inside three-dimensional chimney structure was evaluated using CFD code PHOENICS. The effect of temperature difference between the opposing flows on velocity was also analysed. It is observed that increase in downward flow causes the jet height to decrease due to the opposing momentum of downward flow against the upward jet. The effects of chimney height and temperature difference on the jet height are found to be marginal because of dominating inertial force over buoyancy force for the study. (orig.)

  11. New energy from an old chimney; Nieuwe energie uit een oude schoorsteen

    Energy Technology Data Exchange (ETDEWEB)

    Van Goch, T.A.J. [BAM Techniek, Benningbroek (Netherlands)

    2013-07-15

    A new purpose has been found for the unused monumental stack chimney at the Eindhoven University of Technology. The idea is to use the chimney to provide free cooling. Using advanced simulation and analysis methods, the feasibility of the concept was studied. The results show that it is indeed possible to use the chimney effectively to provide free cooling to the neighbouring Ceres (Central Energy and Control Station) building [Dutch] De ongebruikte monumentale schoorsteen van de Universiteit Eindhoven is nieuw leven ingeblazen door hem in te zetten voor vrije koeling. Een studie naar de haalbaarheid hiervan is uitgevoerd met behulp vangeavanceerde simulatie en analysetechnieken. Het is gebleken dat de schoorsteen inderdaad effectief kan worden ingezet voor het leveren van koeling aan het naastgelegen Ceres (Centraal Energie en Regelstation) gebouw.

  12. Fenestrated and Chimney Technique for Juxtarenal Aortic Aneurysm: A Systematic Review and Pooled Data Analysis

    Science.gov (United States)

    Li, Yue; Hu, Zhongzhou; Bai, Chujie; Liu, Jie; Zhang, Tao; Ge, Yangyang; Luan, Shaoliang; Guo, Wei

    2016-01-01

    Juxtarenal aortic aneurysms (JAA) account for approximately 15% of abdominal aortic aneurysms. Fenestrated endovascular aneurysm repair (FEVAR) and chimney endovascular aneurysm repair (CH-EVAR) are both effective methods to treat JAAs, but the comparative effectiveness of these treatment modalities is unclear. We searched the PubMed, Medline, Embase, and Cochrane databases to identify English language articles published between January 2005 and September 2013 on management of JAA with fenestrated and chimney techniques to conduct a systematic review to compare outcomes of patients with juxtarenal aortic aneurysm (JAA) treated with the two techniques. We compared nine F-EVAR cohort studies including 542 JAA patients and 8 CH-EVAR cohorts with 158 JAA patients regarding techniques success rates, 30-day mortality, late mortality, endoleak events and secondary intervention rates. The results of this systematic review indicate that both fenestrated and chimney techniques are attractive options for JAAs treatment with encouraging early and mid-term outcomes. PMID:26869488

  13. A Semi-Empirical Model for Tilted-Gun Planar Magnetron Sputtering Accounting for Chimney Shadowing

    Science.gov (United States)

    Bunn, J. K.; Metting, C. J.; Hattrick-Simpers, J.

    2015-01-01

    Integrated computational materials engineering (ICME) approaches to composition and thickness profiles of sputtered thin-film samples are the key to expediting materials exploration for these materials. Here, an ICME-based semi-empirical approach to modeling the thickness of thin-film samples deposited via magnetron sputtering is developed. Using Yamamura's dimensionless differential angular sputtering yield and a measured deposition rate at a point in space for a single experimental condition, the model predicts the deposition profile from planar DC sputtering sources. The model includes corrections for off-center, tilted gun geometries as well as shadowing effects from gun chimneys used in most state-of-the-art sputtering systems. The modeling algorithm was validated by comparing its results with experimental deposition rates obtained from a sputtering system utilizing sources with a multi-piece chimney assembly that consists of a lower ground shield and a removable gas chimney. Simulations were performed for gun-tilts ranging from 0° to 31.3° from the vertical with and without the gas chimney installed. The results for the predicted and experimental angular dependence of the sputtering deposition rate were found to have an average magnitude of relative error of for a 0°-31.3° gun-tilt range without the gas chimney, and for a 17.7°-31.3° gun-tilt range with the gas chimney. The continuum nature of the model renders this approach reverse-optimizable, providing a rapid tool for assisting in the understanding of the synthesis-composition-property space of novel materials.

  14. Modeling microbial reaction rates in a submarine hydrothermal vent chimney wall

    Science.gov (United States)

    LaRowe, Douglas E.; Dale, Andrew W.; Aguilera, David R.; L'Heureux, Ivan; Amend, Jan P.; Regnier, Pierre

    2014-01-01

    The fluids emanating from active submarine hydrothermal vent chimneys provide a window into subseafloor processes and, through mixing with seawater, are responsible for steep thermal and compositional gradients that provide the energetic basis for diverse biological communities. Although several models have been developed to better understand the dynamic interplay of seawater, hydrothermal fluid, minerals and microorganisms inside chimney walls, none provide a fully integrated approach to quantifying the biogeochemistry of these hydrothermal systems. In an effort to remedy this, a fully coupled biogeochemical reaction-transport model of a hydrothermal vent chimney has been developed that explicitly quantifies the rates of microbial catalysis while taking into account geochemical processes such as fluid flow, solute transport and oxidation-reduction reactions associated with fluid mixing as a function of temperature. The metabolisms included in the reaction network are methanogenesis, aerobic oxidation of hydrogen, sulfide and methane and sulfate reduction by hydrogen and methane. Model results indicate that microbial catalysis is generally fastest in the hottest habitable portion of the vent chimney (77-102 °C), and methane and sulfide oxidation peak near the seawater-side of the chimney. The fastest metabolisms are aerobic oxidation of H2 and sulfide and reduction of sulfate by H2 with maximum rates of 140, 900 and 800 pmol cm-3 d-1, respectively. The maximum rate of hydrogenotrophic methanogenesis is just under 0.03 pmol cm-3 d-1, the slowest of the metabolisms considered. Due to thermodynamic inhibition, there is no anaerobic oxidation of methane by sulfate (AOM). These simulations are consistent with vent chimney metabolic activity inferred from phylogenetic data reported in the literature. The model developed here provides a quantitative approach to describing the rates of biogeochemical transformations in hydrothermal systems and can be used to constrain the

  15. Quantifying metabolic rates in submarine hydrothermal vent chimneys: A reaction transport model

    Science.gov (United States)

    LaRowe, D.; Dale, A.; Aguilera, D.; Amend, J. P.; Regnier, P.

    2012-12-01

    The fluids emanating from active submarine hydrothermal vent chimneys provide a window into subseafloor processes and, through mixing with seawater, are responsible for steep thermal and compositional gradients that provide the energetic basis for diverse biological communities. Although several models have been developed to better understand the dynamic interplay of seawater, hydrothermal fluid, minerals and microorganisms inside chimney walls, none provide a fully integrated approach to quantifying the biogeochemistry of these hydrothermal systems. In an effort to remedy this, a fully coupled biogeochemical reaction transport model of a hydrothermal vent chimney has been developed that explicitly quantifies the rate of microbial catalysis while taking into account geochemical processes such as fluid flow, solute transport and oxidation-reduction reactions associated with fluid mixing as a function of temperature. Methanogenesis, hydrogen oxidation by oxygen and sulfate, sulfide oxidation by oxygen and methane oxidation by oxygen and sulfate are the metabolisms included in the reaction network. Model results indicate that microbial catalysis is fastest in the hottest habitable portion of the vent chimney except for methane oxidation by oxygen, which peaks near the seawater-side of the chimney at 20 nmol /cm^3 yr. The dominant metabolisms in the chimney are hydrogen oxidation by sulfate and oxygen and sulfide oxidation at peak rates 3200 , 300 and 900 nmol /cm^3 yr, respectively. The maximum rate of hydrogenotrophic methanogensis is just under 0.07 nmol /cm^3 yr, the slowest of the metabolisms considered. Due to thermodynamic inhibition, there is no anaerobic oxidation of methane by sulfate (AOM). The model developed here provides a quantitative approach to understanding the rates of biogeochemical transformations in hydrothermal systems and can be used to better understand the role of microbial activity in the deep subsurface.

  16. Chimney and periscope technique for emergent treatment of spontaneous aortic rupture.

    Science.gov (United States)

    Trellopoulos, George; Georgakarakos, Efstratios; Pelekas, Dimitrios; Papachristodoulou, Athanasia; Argyriou, Christos; Georgiadis, George S

    2014-07-01

    Aortic rupture comprises a potentially fatal condition necessitating emergent treatment. Endovascular sealing of the rupture site is often combined with the use of chimney- and periscope stent placement to preserve perfusion of aortic branches. We present a case of successful endovascular management of contained aortic rupture in a 78-year-old patient. The left brachial access facilitated stenting of the celiac and superior mesenteric arteries, whereas the left femoral route served stenting of the renal artery. One-month follow-up confirmed complete sealing, stent patency, and absence of endograft migration. The combined periscope and chimney technique is feasible and effective in the emergency setting. PMID:24517987

  17. Structural Integrity Evaluation of an New In-Chimney Bracket Structures for HANARO

    International Nuclear Information System (INIS)

    In HANARO are there provided three hexagonal irradiation holes (CT, IR1 and IR2) in the central region of the core while four circular irradiation holes (OR3 ∼ OR6) in the outer core. There exist two types of irradiation facilities: uninstrumented or instrumented. The uninstrumented irradiation facility is little influenced by the coolant flow. But the dynamic behavior by the flow-induced vibration (FIV) and seismic loads is expected to largely occur in case of the instrumented test facility due to the long guide tube to protect the instrumentation cables. To suppress this dynamic behavior of the facility, the in-chimney bracket was designed. As a supplementary supporting structure for irradiation facility, this bracket will hold guide tubes whose holding position of the instrumented facility in CT or IR is the middle part of the instrumented facility between the hole spider and the robot arm already provided in the reactor pool liner. On the while, the bracket will grip the upper part of the guide tube when it is applied to hold the instrumented facility loaded in OR sites. Therefore it is believed that the irradiation test can be successfully conducted since this bracket can reduce the FIV and dynamic response to seismic load as well. In new in-chimney bracket, IR1 is reserved for IPS(In-Pile Section) so only CT/IR2 guide tubes are supported by CT/IR clamp units and the shape of In-chimney bracket is redesigned. For evaluating the structural integrity on the new in-chimney bracket and related reactor structures, ANSYS finite element analysis model is developed and the dynamic characteristics are analyzed. The seismic response analyses of new in-chimney bracket and related reactor structures of HANARO under the design earthquake response spectrum loads of OBE(0.1g) and SSE(0.2g) are performed. The response shows that the stress values for main points on the reactor structures and the new in-chimney bracket for seismic loads are within the ASME Code limits. It is

  18. Numerical analysis of the hemodynamics of an abdominal aortic aneurysm repaired using the endovascular chimney technique.

    Science.gov (United States)

    Ben Gur, Hila; Kosa, Gabor; Brand, Moshe

    2015-08-01

    This paper presents a numerical analysis of the hemodynamics in an abdominal aorta (AA) with an aneurysm repaired by a stent graft (SG) system using the chimney technique. Computational fluid dynamics (CFD) simulations were conducted in a model of an AA repaired with a chimney stent graft (CSG) inserted into a renal artery parallel to an aortic SG and a model of a healthy AA. Comparing the simulation results of these two cases suggests that the presence of the CSG in the AA causes changes in average wall shear stress (WSS), potentially damaging recirculation zones, and additional changes in flow patterns. PMID:26736427

  19. On the form of the power equation for modeling solar chimney power plant systems

    CERN Document Server

    Fathi, Nima; Vorobieff, Peter

    2015-01-01

    Recently several mathematical models of a solar chimney power plant were derived, studied for a variety of boundary conditions, and compared against CFD calculations. The importance of these analyses is about the accuracy of the derived pressure drop and output power equation for solar chimney power plant systems (SCPPS). We examine the assumptions underlying the derivation and present reasons to believe that some of the derived equations, specifically the power equation in this model, may require a correction to be applicable in more realistic conditions. The analytical resutls are compared against the available experimental data from the Manzanares power plant.

  20. Linkages between mineralogy, fluid chemistry, and microbial communities within hydrothermal chimneys from the Endeavour Segment, Juan de Fuca Ridge

    Science.gov (United States)

    Lin, T. J.; Ver Eecke, H. C.; Breves, E. A.; Dyar, M. D.; Jamieson, J. W.; Hannington, M. D.; Dahle, H.; Bishop, J. L.; Lane, M. D.; Butterfield, D. A.; Kelley, D. S.; Lilley, M. D.; Baross, J. A.; Holden, J. F.

    2016-02-01

    Rock and fluid samples were collected from three hydrothermal chimneys at the Endeavour Segment, Juan de Fuca Ridge to evaluate linkages among mineralogy, fluid chemistry, and microbial community composition within the chimneys. Mössbauer, midinfrared thermal emission, and visible-near infrared spectroscopies were utilized for the first time to characterize vent mineralogy, in addition to thin-section petrography, X-ray diffraction, and elemental analyses. A 282°C venting chimney from the Bastille edifice was composed primarily of sulfide minerals such as chalcopyrite, marcasite, and sphalerite. In contrast, samples from a 300°C venting chimney from the Dante edifice and a 321°C venting chimney from the Hot Harold edifice contained a high abundance of the sulfate mineral anhydrite. Geochemical modeling of mixed vent fluids suggested the oxic-anoxic transition zone was above 100°C at all three vents, and that the thermodynamic energy available for autotrophic microbial redox reactions favored aerobic sulfide and methane oxidation. As predicted, microbes within the Dante and Hot Harold chimneys were most closely related to mesophilic and thermophilic aerobes of the Betaproteobacteria and Gammaproteobacteria and sulfide-oxidizing autotrophic Epsilonproteobacteria. However, most of the microbes within the Bastille chimney were most closely related to mesophilic and thermophilic anaerobes of the Deltaproteobacteria, especially sulfate reducers, and anaerobic hyperthermophilic archaea. The predominance of anaerobes in the Bastille chimney indicated that other environmental factors promote anoxic conditions. Possibilities include the maturity or fluid flow characteristics of the chimney, abiotic Fe2+ and S2- oxidation in the vent fluids, or O2 depletion by aerobic respiration on the chimney outer wall.

  1. Nonlinear mushy-layer convection with chimneys: stability and optimal solute fluxes

    CERN Document Server

    Wells, Andrew J; Orszag, Steven A

    2012-01-01

    We model buoyancy-driven convection with chimneys -- channels of zero solid fraction -- in a mushy layer formed during directional solidification of a binary alloy in two-dimensions. A large suite of numerical simulations is combined with scaling analysis in order to study the parametric dependence of the flow. Stability boundaries are calculated for states of finite-amplitude convection with chimneys, which for a narrow domain can be interpreted in terms of a modified Rayleigh number criterion based on the domain width and mushy-layer permeability. For solidification in a wide domain with multiple chimneys, it has previously been hypothesised that the chimney spacing will adjust to optimise the rate of removal of potential energy from the system. For a wide variety of initial liquid concentration conditions, we consider the detailed flow structure in this optimal state and derive scaling laws for how the flow evolves as the strength of convection increases. For moderate mushy-layer Rayleigh numbers these flo...

  2. Annual performance analysis of the solar chimney power plant in Sinkiang, China

    International Nuclear Information System (INIS)

    Highlights: • A theoretical model was developed concerning hourly variation of solar radiation. • A limitation on maximum collector radius of an SCPP with a given chimney exists. • Annual performance of a 100 MW SCPP was predicted in hourly interval. • The Hami region is considered suitable for the construction of SCPP. - Abstract: To obtain more accurate prediction of the annual performance of solar chimney power plants (SCPPs), a comprehensive theoretical model is developed by taking into account the hourly variation of solar radiation. The effects of the collector and chimney radii on the power output of the SCPP are analyzed, and the results reveal that a limitation on the maximum collector radius exists for the maximum attainable power output of the SCPP. Then four designs of 100 MW SCPPs with different combinations of collector and chimney radii are proposed and the most cost effective one is chosen from among the four SCPPs. The annual power output of the chosen SCPP in the Hami region is estimated at an interval of 1 h for a whole year. The results indicate that the power generation of SCPP presents obvious seasonal variation. Furthermore, the use of 14% of the unused land in the Hami region for the installation of SCPPs would satisfy the annual power requirement for the whole of the Sinkiang region

  3. Endovascular Aneurysm Sealing for Juxtarenal Aneurysm Using the Nellix Device and Chimney Covered Stents

    NARCIS (Netherlands)

    Dijkstra, Martijn L.; Lardenoye, Jan Willem; van Oostayen, Jacques A.; Zeebregts, Clark J.; Reijnen, Michel M. P. J.

    2014-01-01

    Purpose: To show the feasibility of the Nellix device in conjunction with a chimney technique for treating juxtarenal aneurysms in two patients who were deemed unsuitable for fenestrated endovascular aneurysm repair or open surgery. Case Reports: Two men aged 83 and 81 years were referred with a jux

  4. Upward-migrating methane induced seismic chimney formation in the Nordland Group, Southern Viking Graben

    Science.gov (United States)

    Kempka, Thomas; Unger, Victoria; Kühn, Michael

    2016-04-01

    The Nordland Group in the Southern Viking Graben hosts seismic chimneys, represented by anomalies in seismic data and determined by residual methane accumulations. These seismic chimneys are generally interpreted as focused fluid flow structures, and thus pose the risk of potential fluid leakage in geological subsurface utilization. The aim of the present study was to assess two popular scientific hypotheses on seismic chimney formation in the Nordland Group. The first one assumes excess pore pressure to result from buoyancy effects caused by upward-migrating methane and the development of a gas column with a thickness of several hundred meters, whereas the second one considers the load of the Fennoscandian ice sheet to be responsible for occurrence of hydraulic fracturing. In this context, we applied coupled hydromechanical simulations to determine the mechanism inducing the formation of these potential leakage pathways. Our simulation results demonstrate that hydraulic fracturing in the Nordland Group already occurs before the maximum methane column heights develop below. Consequently, the load of the Fennoscandian ice sheet is not initiating seismic chimneys formation.

  5. A Cost Effective Desalination Plant Using a Solar Chimney with Recycled Aluminum Can Collector

    Directory of Open Access Journals (Sweden)

    Singuru Rajesh

    2016-01-01

    Full Text Available The main objective of the work was to use solar energy for desalination of water. A solar chimney desalination system, which includes the solar chimney, solar collector, evaporation system, and passive condenser, was designed and built. The air enters into collector and gets heated and released at the bottom of chimney. Due to draught effect dry air goes upward. The air is humidified by spraying salt water into the hot air stream using a mistifier at the middle of chimney. Then, the partial vapours contained in the air are condensed to give desalinated water. The performance of the integrated system including power and potable water production was estimated and the results were discussed. With a 3.4 m height setup, experimental test rig was capable of evaporating 3.77 L water daily condensing 2.3 L water. It is compact in nature as it is easy to assemble and dissemble. It can be used for purifying rain water in summer under rain water harvesting. Because of using country wood, recycled Al cans, and GI sheet in fabrication, it is lower in cost.

  6. Geochemical processes and fluxes at a methane gas chimney on the Hikurangi Margin (New Zealand)

    Science.gov (United States)

    Dale, A.; Haffert, L.; Hütten, E.; Crutchley, G.; Greinert, J.; de Haas, H.; de Stigter, H.; Bialas, J.

    2012-04-01

    The initial results presented in this study focus on the pore water geochemistry of Takahe methane seep located at 1050 m water depth on the Hikurangi Margin. The main objectives are to characterize and quantify the geochemical processes occurring in the upper meters of sediment. Parasound images of the study site showed a well-defined seismic blanking zone of around 230 m in diameter that is likely generated by trapped methane gas. At the northern edge of this seismic gas chimney bubble release has been observed by using hydroacoustic methods (singlebeam and multibeam echosounders). At the seafloor the more northern part of the chimney area showed white Beggiatoa bacterial mats and in places dark sediment patches due to geochemically reduced environments. No other "seep specific" fauna as tube worms or clams as well as no massive chemoherm carbonate where found in the area. This points towards a rather young seepage history. Geochemical data measured in 8 gravity cores across the gas chimney support this notion and gas hydrate layers several cm thick were observed in several cores. Sulphate and total alkalinity concentrations varied little from seawater values in the upper 50 to 100 cm towards the southerly end of the seismic gas chimney area; a feature attributed to irrigation by escaping methane gas bubbles. At these stations, the pore fluids were highly enriched in biogenic methane. However, the dissolved methane was mostly consumed anaerobically by sulphate, resulting in steep gradients of sulphate, methane, total alkalinity and hydrogen sulphide. Geochemical gradients at reference site immediately outside the chimney area were essentially vertical, indicating very little upwards transport and dissolution of methane. The geochemical data are applied to a numerical reaction-transport model to quantify the total upward flux of methane at each station and, ultimately, for the entire gas chimney. Temperature measurements of thermistor probes attached to the barrel

  7. Origin of a native sulfur chimney in the Kueishantao hydrothermal field, offshore northeast Taiwan

    Institute of Scientific and Technical Information of China (English)

    ZENG; ZhiGang; LIU; ChangHua; CHEN; ChenTung; A; YIN; XueBo; CHEN; DaiGeng; WANG; XiaoYuan; WANG; XiaoMei; ZHANG; GuoLiang

    2007-01-01

    Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences.Using an Elan DRC II ICP-MS,and combining the sulfur isotopic compositions of native sulfur samples,we studied the sources and formation of a native sulfur chimney.The results show,when comparing them with native sulfur from crater lakes and other volcanic areas,that the native sulfur content of this chimney is very high (99.96%),the rare earth element (REE) and trace element constituents of the chimney are very low (ΣREE<21×10-9),and the chondrite-normalized REE patterns of the native sulfur samples are similar to those of the Kueishantao andesite,implying that the interaction of subseafloor fluid-andesite at the Kueishantao hydrothermal field was of short duration.The sulfur isotopic compositions of the native sulfur samples reveal that the sulfur of the chimney,from H2S and SO2,originated by magmatic degassing and that the REEs and trace elements are mostly from the Kueishantao andesite and partly from seawater.Combining these results with an analysis of the thermodynamics,it is clear that from the relatively low temperature (<116℃),the oxygenated and acidic environment is favorable for formation of this native sulfur chimney in the Kueishantao hydrothermal field.

  8. Experimental and numerical characterization of wind-induced pressure coefficients on nuclear buildings and chimney exhausts

    Energy Technology Data Exchange (ETDEWEB)

    Ricciardi, Laurent, E-mail: laurent.ricciardi@irsn.fr; Gélain, Thomas; Soares, Sandrine

    2015-10-15

    Highlights: • Experiments on scale models of nuclear buildings and chimney exhausts were performed. • Pressure coefficient fields on buildings are shown for various wind directions. • Evolution of pressure coefficient vs U/W ratio is given for various chimney exhausts. • RANS simulations using SST k–ω turbulence model were performed on most studied cases. • A good agreement is overall observed, with Root Mean Square Deviation lower than 0.15. - Abstract: Wind creates pressure effects on different surfaces of buildings according to their exposure to the wind, in particular at external communications. In nuclear facilities, these effects can change contamination transfers inside the building and can even lead to contamination release into the environment, especially in damaged (ventilation stopped) or accidental situations. The diversity of geometries of facilities requires the use of a validated code for predicting pressure coefficients, which characterize the wind effect on the building walls and the interaction between the wind and chimney exhaust. The first aim of a research program launched by the French Institut de Radioprotection et de Sûreté Nucléaire (IRSN), was therefore to acquire experimental data of the mean pressure coefficients for different geometries of buildings and chimneys through wind tunnel tests and then to validate a CFD code (ANSYS CFX) from these experimental results. The simulations were performed using a steady RANS approach and a two-equation SST k–ω turbulence model. After a mesh sensitivity study for one configuration of building and chimney, a comparison was carried out between the numerical and experimental values for other studied configurations. This comparison was generally satisfactory, averaged over all measurement points, with values of Root Mean Square Deviations lower than 0.15 for most cases.

  9. Experimental and numerical characterization of wind-induced pressure coefficients on nuclear buildings and chimney exhausts

    International Nuclear Information System (INIS)

    Highlights: • Experiments on scale models of nuclear buildings and chimney exhausts were performed. • Pressure coefficient fields on buildings are shown for various wind directions. • Evolution of pressure coefficient vs U/W ratio is given for various chimney exhausts. • RANS simulations using SST k–ω turbulence model were performed on most studied cases. • A good agreement is overall observed, with Root Mean Square Deviation lower than 0.15. - Abstract: Wind creates pressure effects on different surfaces of buildings according to their exposure to the wind, in particular at external communications. In nuclear facilities, these effects can change contamination transfers inside the building and can even lead to contamination release into the environment, especially in damaged (ventilation stopped) or accidental situations. The diversity of geometries of facilities requires the use of a validated code for predicting pressure coefficients, which characterize the wind effect on the building walls and the interaction between the wind and chimney exhaust. The first aim of a research program launched by the French Institut de Radioprotection et de Sûreté Nucléaire (IRSN), was therefore to acquire experimental data of the mean pressure coefficients for different geometries of buildings and chimneys through wind tunnel tests and then to validate a CFD code (ANSYS CFX) from these experimental results. The simulations were performed using a steady RANS approach and a two-equation SST k–ω turbulence model. After a mesh sensitivity study for one configuration of building and chimney, a comparison was carried out between the numerical and experimental values for other studied configurations. This comparison was generally satisfactory, averaged over all measurement points, with values of Root Mean Square Deviations lower than 0.15 for most cases

  10. Iron-sulfide-bearing chimneys as potential catalytic energy traps at life's emergence.

    Science.gov (United States)

    Mielke, Randall E; Robinson, Kirtland J; White, Lauren M; McGlynn, Shawn E; McEachern, Kavan; Bhartia, Rohit; Kanik, Isik; Russell, Michael J

    2011-12-01

    The concept that life emerged where alkaline hydrogen-bearing submarine hot springs exhaled into the most ancient acidulous ocean was used as a working hypothesis to investigate the nature of precipitate membranes. Alkaline solutions at 25-70°C and pH between 8 and 12, bearing HS(-)±silicate, were injected slowly into visi-jars containing ferrous chloride to partially simulate the early ocean on this or any other wet and icy, geologically active rocky world. Dependent on pH and sulfide content, fine tubular chimneys and geodal bubbles were generated with semipermeable walls 4-100 μm thick that comprised radial platelets of nanometric mackinawite [FeS]±ferrous hydroxide [∼Fe(OH)(2)], accompanied by silica and, at the higher temperature, greigite [Fe(3)S(4)]. Within the chimney walls, these platelets define a myriad of micropores. The interior walls of the chimneys host iron sulfide framboids, while, in cases where the alkaline solution has a pH>11 or relatively low sulfide content, their exteriors exhibit radial flanges with a spacing of ∼4 μm that comprise microdendrites of ferrous hydroxide. We speculate that this pattern results from outward and inward radial flow through the chimney walls. The outer Fe(OH)(2) flanges perhaps precipitate where the highly alkaline flow meets the ambient ferrous iron-bearing fluid, while the intervening troughs signal where the acidulous iron-bearing solutions could gain access to the sulfidic and alkaline interior of the chimneys, thereby leading to the precipitation of the framboids. Addition of soluble pentameric peptides enhances membrane durability and accentuates the crenulations on the chimney exteriors. These dynamic patterns may have implications for acid-base catalysis and the natural proton motive force acting through the matrix of the porous inorganic membrane. Thus, within such membranes, steep redox and pH gradients would bear across the nanometric platelets and separate the two counter-flowing solutions

  11. Assessing the influence of physical, geochemical and biological factors on anaerobic microbial primary productivity within hydrothermal vent chimneys.

    Science.gov (United States)

    Olins, H C; Rogers, D R; Frank, K L; Vidoudez, C; Girguis, P R

    2013-05-01

    Chemosynthetic primary production supports hydrothermal vent ecosystems, but the extent of that productivity and its governing factors have not been well constrained. To better understand anaerobic primary production within massive vent deposits, we conducted a series of incubations at 4, 25, 50 and 90 °C using aggregates recovered from hydrothermal vent structures. We documented in situ geochemistry, measured autochthonous organic carbon stable isotope ratios and assessed microbial community composition and functional gene abundances in three hydrothermal vent chimney structures from Middle Valley on the Juan de Fuca Ridge. Carbon fixation rates were greatest at lower temperatures and were comparable among chimneys. Stable isotope ratios of autochthonous organic carbon were consistent with the Calvin-Benson-Bassham cycle being the predominant mode of carbon fixation for all three chimneys. Chimneys exhibited marked differences in vent fluid geochemistry and microbial community composition, with structures being differentially dominated by gamma (γ) or epsilon (ε) proteobacteria. Similarly, qPCR analyses of functional genes representing different carbon fixation pathways showed striking differences in gene abundance among chimney structures. Carbon fixation rates showed no obvious correlation with observed in situ vent fluid geochemistry, community composition or functional gene abundance. Together, these data reveal that (i) net anaerobic carbon fixation rates among these chimneys are elevated at lower temperatures, (ii) clear differences in community composition and gene abundance exist among chimney structures, and (iii) tremendous spatial heterogeneity within these environments likely confounds efforts to relate the observed rates to in situ microbial and geochemical factors. We also posit that microbes typically thought to be mesophiles are likely active and growing at cooler temperatures, and that their activity at these temperatures comprises the

  12. Assessing the influence of physical, geochemical and biological factors on anaerobic microbial primary productivity within hydrothermal vent chimneys.

    Science.gov (United States)

    Olins, H C; Rogers, D R; Frank, K L; Vidoudez, C; Girguis, P R

    2013-05-01

    Chemosynthetic primary production supports hydrothermal vent ecosystems, but the extent of that productivity and its governing factors have not been well constrained. To better understand anaerobic primary production within massive vent deposits, we conducted a series of incubations at 4, 25, 50 and 90 °C using aggregates recovered from hydrothermal vent structures. We documented in situ geochemistry, measured autochthonous organic carbon stable isotope ratios and assessed microbial community composition and functional gene abundances in three hydrothermal vent chimney structures from Middle Valley on the Juan de Fuca Ridge. Carbon fixation rates were greatest at lower temperatures and were comparable among chimneys. Stable isotope ratios of autochthonous organic carbon were consistent with the Calvin-Benson-Bassham cycle being the predominant mode of carbon fixation for all three chimneys. Chimneys exhibited marked differences in vent fluid geochemistry and microbial community composition, with structures being differentially dominated by gamma (γ) or epsilon (ε) proteobacteria. Similarly, qPCR analyses of functional genes representing different carbon fixation pathways showed striking differences in gene abundance among chimney structures. Carbon fixation rates showed no obvious correlation with observed in situ vent fluid geochemistry, community composition or functional gene abundance. Together, these data reveal that (i) net anaerobic carbon fixation rates among these chimneys are elevated at lower temperatures, (ii) clear differences in community composition and gene abundance exist among chimney structures, and (iii) tremendous spatial heterogeneity within these environments likely confounds efforts to relate the observed rates to in situ microbial and geochemical factors. We also posit that microbes typically thought to be mesophiles are likely active and growing at cooler temperatures, and that their activity at these temperatures comprises the

  13. Solar chimney: A sustainable approach for ventilation and building space conditioning

    Directory of Open Access Journals (Sweden)

    Lal, S.,

    2013-03-01

    Full Text Available The residential and commercial buildings demand increase with rapidly growing population. It leads to the vertical growth of the buildings and needs proper ventilation and day-lighting. The natural air ventilation system is not significantly works in conventional structure, so fans and air conditioners are mandatory to meet the proper ventilation and space conditioning. Globally building sector consumed largest energy and utmost consumed in heating, ventilation and space conditioning. This load can be reduced by application of solar chimney and integrated approaches in buildings for heating, ventilation and space conditioning. It is a sustainable approach for these applications in buildings. The authors are reviewed the concept, various method of evaluation, modelings and performance of solar chimney variables, applications and integrated approaches.

  14. Barometric pressure transient testing applications at the Nevada Test Site. Nuclear chimney analysis. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, J.M.

    1985-12-01

    Investigations of barometric pressure testing of NTS nuclear chimneys were reviewed. This review includes the models used in the interpretation, methods of analysis, and results. Analytic and semi-analytic models were presented and applied to both historical data and new data taken for this current project. An interpretation technique based on non-linear least squares methods was used to analyze this data in terms of historic and more recent chimney models. Finally, a detailed discussion of radioactive gas transport due to surface barometric pressure fluctuations was presented. This mechanism of transport, referred to as ''barometric pumping,'' is presented in terms of conditions likely to be encountered at the NTS. The report concludes with a discussion of the current understanding of gas flow properties in the alluvial and volcanic areas of the NTS, and suggestions for future efforts directed toward increasing this understanding are presented.

  15. Scientific and Cost Effective Monitoring: The Case of an Aerial Insectivore, the Chimney Swift

    Directory of Open Access Journals (Sweden)

    Sébastien Rioux

    2010-12-01

    Full Text Available The increased pace of species listing worldwide, coupled with the scarcity of conservation funding, promote the use of targeted monitoring. We applied the recommendations of Nichols and Williams (Trends in Ecology and Evolution 2006 24:668-673 to optimize the Québec Chimney Swift Monitoring Program, an ongoing volunteer-based monitoring initiative launched in 1998. Past objectives of the program were to fill knowledge gaps about occupancy patterns at roosts sites, determine spatial and temporal distribution of Chimney Swifts (Chaetura pelagica across the province, locate active nest sites, and monitor temporal fluctuations of the population. By applying an adaptive management framework, we modified the current monitoring scheme into a more focused initiative testing newly developed hypotheses about the state of the system. This new approach yielded significant scientific gains as well as annual savings of 19.6%. It may prove pertinent to current and future swift monitoring initiatives and to other aerial insectivore species.

  16. Barometric pressure transient testing applications at the Nevada Test Site. Nuclear chimney analysis. Final report

    International Nuclear Information System (INIS)

    Investigations of barometric pressure testing of NTS nuclear chimneys were reviewed. This review includes the models used in the interpretation, methods of analysis, and results. Analytic and semi-analytic models were presented and applied to both historical data and new data taken for this current project. An interpretation technique based on non-linear least squares methods was used to analyze this data in terms of historic and more recent chimney models. Finally, a detailed discussion of radioactive gas transport due to surface barometric pressure fluctuations was presented. This mechanism of transport, referred to as ''barometric pumping,'' is presented in terms of conditions likely to be encountered at the NTS. The report concludes with a discussion of the current understanding of gas flow properties in the alluvial and volcanic areas of the NTS, and suggestions for future efforts directed toward increasing this understanding are presented

  17. Scientific and Cost Effective Monitoring: The Case of an Aerial Insectivore, the Chimney Swift

    OpenAIRE

    Sébastien Rioux; Savard, Jean-Pierre L.; François Shaffer

    2010-01-01

    The increased pace of species listing worldwide, coupled with the scarcity of conservation funding, promote the use of targeted monitoring. We applied the recommendations of Nichols and Williams (Trends in Ecology and Evolution 2006 24:668-673) to optimize the Québec Chimney Swift Monitoring Program, an ongoing volunteer-based monitoring initiative launched in 1998. Past objectives of the program were to fill knowledge gaps about occupancy patterns at roosts sites, determine spatial and tempo...

  18. Basement Kind Effects on Air Temperature of a Solar Chimney in Baghdad - Iraq Weather

    Directory of Open Access Journals (Sweden)

    Miqdam Tariq Chaichan

    2011-01-01

    Full Text Available A solar updraft tower power plant (solar tower is a solar thermal power plant that utilizes a combination of solar air collector and central updraft tube to generate an induced convective flow which drives pressure staged turbines to generate electricity. This paper presents practical results of a prototype of a solar chimney with thermal mass, where the glass surface is replaced by transparence plastic cover. The study focused on chimney's basements kind effect on collected air temperatures. Three basements were used: concrete, black concrete and black pebbles basements. The study was conducted in Baghdad from August to November 2009. The results show that the best chimney efficiency attained was 49.7% for pebbles base. The highest collected air temperature reached was 49ºC when using the black pebbles basement also.also, the maximum basement temperature measured was 59ºC for black pebbles. High increaments in collected air temperatures were achieved in comparison with the ambient air temperatures for the three basement kinds. The highest temperature difference reached was 22ºC with the pebble ground.

  19. Biogeochemical insights into microbe-mineral-fluid interactions in hydrothermal chimneys using enrichment culture.

    Science.gov (United States)

    Callac, Nolwenn; Rouxel, Olivier; Lesongeur, Françoise; Liorzou, Céline; Bollinger, Claire; Pignet, Patricia; Chéron, Sandrine; Fouquet, Yves; Rommevaux-Jestin, Céline; Godfroy, Anne

    2015-05-01

    Active hydrothermal chimneys host diverse microbial communities exhibiting various metabolisms including those involved in various biogeochemical cycles. To investigate microbe-mineral-fluid interactions in hydrothermal chimney and the driver of microbial diversity, a cultural approach using a gas-lift bioreactor was chosen. An enrichment culture was performed using crushed active chimney sample as inoculum and diluted hydrothermal fluid from the same vent as culture medium. Daily sampling provided time-series access to active microbial diversity and medium composition. Active archaeal and bacterial communities consisted mainly of sulfur, sulfate and iron reducers and hydrogen oxidizers with the detection of Thermococcus, Archaeoglobus, Geoglobus, Sulfurimonas and Thermotoga sequences. The simultaneous presence of active Geoglobus sp. and Archaeoglobus sp. argues against competition for available carbon sources and electron donors between sulfate and iron reducers at high temperature. This approach allowed the cultivation of microbial populations that were under-represented in the initial environmental sample. The microbial communities are heterogeneously distributed within the gas-lift bioreactor; it is unlikely that bulk mineralogy or fluid chemistry is the drivers of microbial community structure. Instead, we propose that micro-environmental niche characteristics, created by the interaction between the mineral grains and the fluid chemistry, are the main drivers of microbial diversity in natural systems.

  20. The application of masonry chimney venting tables for oil-fired appliances

    Energy Technology Data Exchange (ETDEWEB)

    Krajewski, R.F.; Strasser, J. [Brookhaven National Lab., Upton, NY (United States)

    1995-04-01

    This paper presents an overview of the results of work in developing a set of rational guidelines for the venting of modern oil-fired appliances. The activities included the continued development and completion of the Oil-Heat Vent Analysis Program (OHVAP), Version 1.0 and the interpretation of nearly 2,000 runs in preparing recommendations for presentation in table form. These results are presented in the form of venting tables for the installation of chimney vent systems for mid- and high-efficiency oil-fired heating appliances using masonry chimneys. A brief description of OHVAP is given as well as a discussion of what the program does. Recommendations based on the results of OHVAP are presented in the form of five tables spanning oil-fired appliance Steady state Efficiencies (Eff{sub ss}) of 80% to 88%. The assumptions used in the calculations and examples of the computed results are presented as well as a discussion of the rationale for masonry chimney system treatment. Working examples are given with suggested diagnostic approaches for application of the table recommendations.

  1. Biogeochemistry of Hydrothermal Chimney Environments: Continuous-Flow Experiments at in situ Temperature and Pressure

    Science.gov (United States)

    Houghton, J.; Seyfried, W.; Reysenbach, A.; Banta, A.; von Damm, K.

    2002-12-01

    Recent interest in the existence of a subsurface microbial biosphere at hydrothermal vents has resulted in a plethora of new questions that might best be answered using interdisciplinary techniques that combine geochemistry, microbial ecology, and molecular biology. Ideally, such studies will quantitatively address issues concerning what organisms exist in the subsurface, what metabolisms are sustained in the hydrothermal environment, and what effects these active organisms might have on the nearby fluid and rock. We present a new experimental approach to studying these questions that enables monitoring of an active hydrothermal community of microbes in the presence of chimney material at in situ temperature and pressure. This apparatus is designed as a continuous-flow reactor from which fluid samples can be extracted during the course of the experiment to measure chemistry and biomass, and at the termination of an experiment solids can be extracted for analysis of mineralogical changes and microbial identification. Results of a series of experiments conducted using hydrothermal chimney material (solids and microbial community) collected from 21° N and 9° N East Pacific Rise are presented. At 70° C, a seawater-based fluid with additional NO3-, CO2(aq), and H2(aq) was reacted with chimney material from L vent, 9° N EPR. The fluid lost significant NO3-, PO43-, and gained SO42- even after accounting for the contribution from anhydrite dissolution. No significant sulfide or iron was observed in the fluid. Analysis of the DNA extracted from the solids at the termination of the experiment using partial 16S-rRNA sequence data revealed that the dominant bacteria were S-oxidizing tube worm endosymbionts, a S/NO3- reducing member of the Deferribacter genus, and a H2-oxidizing/NO3- reducing strain of Aquifex. Mineral analysis from before and after the experiment indicates the loss of pyrrhotite (FeS) and anhydrite (CaSO4), and the gain of an Fe-oxide phase tentatively

  2. A parametric study on the feasibility of solar chimney power plants in North Cyprus conditions

    International Nuclear Information System (INIS)

    Highlights: • A parametric for solar chimney power plants (SCPPs) feasibility approach is proposed. • We found the annual electricity production of a 30 MW SCPP to be 94.5 GW h. • We compare this production with the same capacity fossil fuel thermal power plant. • We assess the effect of varying some parameters on economic viability of the SCPP. • Capital expenditure plays a critical role in assessing SCPP economic feasibility. - Abstract: The present work investigates the feasibility of installing a solar chimney power plant (SCPP) under North Cyprus (NC) conditions. The method utilized for the simulations of electricity production was compared and verified by the experimental recordings of the prototype in Manzanares, Spain, before carrying out performance predictions for different plant sizes, collector diameters and chimney heights. The annual electricity production of a 30 MW hypothetical SCPP system is estimated to be 94.5 GW h, which can cater for annual electricity needs of over 22,128 residences without any CO2, NOx and SOx emissions. For an installation cost of €145 million, it was estimated that the savings-to-investment ratio (SIR) would be 1.14, indicating a marginal economic feasibility. It is important to find ways of reducing the installation cost in order to strengthen the economic viability of the system. Considering that, at present, fuel oil no. 6 is being used in NC to produce electricity; the SCPP would cause avoidance of 24,840 tonnes of CO2 delivered into the atmosphere annually, if it replaced an equivalently-sized conventional power unit. To identify the most feasible cost option for the installation of the SCPP, a parametric cost analysis is carried out by varying the parameters such as; capital investment costs, carbon dioxide emission trading system price, chimney height, collector diameter and SCPP plant capacity. In all cases, the effect of these parameters on the economic feasibility indicators, such as SIR, net present

  3. Tellurium-bearing minerals in zoned sulfide chimneys from Cu-Zn massive sulfide deposits of the Urals, Russia

    Science.gov (United States)

    Maslennikov, V. V.; Maslennikova, S. P.; Large, R. R.; Danyushevsky, L. V.; Herrington, R. J.; Stanley, C. J.

    2013-02-01

    Tellurium-bearing minerals are generally rare in chimney material from mafic and bimodal felsic volcanic hosted massive sulfide (VMS) deposits, but are abundant in chimneys of the Urals VMS deposits located within Silurian and Devonian bimodal mafic sequences. High physicochemical gradients during chimney growth result in a wide range of telluride and sulfoarsenide assemblages including a variety of Cu-Ag-Te-S and Ag-Pb-Bi-Te solid solution series and tellurium sulfosalts. A change in chimney types from Fe-Cu to Cu-Zn-Fe to Zn-Cu is accompanied by gradual replacement of abundant Fe-, Co, Bi-, and Pb- tellurides by Hg, Ag, Au-Ag telluride and galena-fahlore with native gold assemblages. Decreasing amounts of pyrite, both colloform and pseudomorphic after pyrrhotite, isocubanite ISS and chalcopyrite in the chimneys is coupled with increasing amounts of sphalerite, quatz, barite or talc contents. This trend represents a transition from low- to high sulphidation conditions, and it is observed across a range of the Urals deposits from bimodal mafic- to bimodal felsic-hosted types: Yaman-Kasy → Molodezhnoye → Uzelga → Valentorskoye → Oktyabrskoye → Alexandrinskoye → Tash-Tau → Jusa.

  4. Improvement of the Vertical Dispersion of Pollutants Resulting From Chimneys by Thermosiphon Effect

    Directory of Open Access Journals (Sweden)

    A. O.M. Mahmoud

    2006-01-01

    Full Text Available The dispersion of pollutants, resulting from industrial chimneys, in the surrounding atmosphere made the interest in realizing emitting conditions appears. It also encourages the vertical dispersion of these pollutants. At a given wind velocity, the height of this dispersion is essentially a function of the thermal power and the flow rate at the chimney exit. To improve these qualities, we propose a system that could be integrated to the industrial chimney exit. An open-ended vertical cylinder of larger diameter essentially constitutes this system. In order to determine the characteristics of the resulting flow, we simulated the problem in the laboratory while studying the evolution of a free thermal plume generated by a disk heated uniformly by the Joule effect at a constant temperature. The thermal plume expands in a quiet environment of isotherm temperature. To study the thermosiphon effect, we surrounded the plume source by a vertical cylinder opened at the extremities. Thermal radiation emitted by the hot disk heats the cylinder wall. The pressure drop due to the acceleration of the flow at the cylinder inlet causes the appearance of thermosiphon effect around the thermal plume. The analysis of the average fields of velocity and temperature shows that the thermosiphon effect entails a good homogenization of the flow at the system exit. Furthermore, the comparison of the results obtained at the exit of the two studied systems shows a relative increase of the flow rate and the thermal power absorbed by the air of the order of 50% under the thermosiphon effect. This result is expressed by a gain in the plume rise of the order of 40%.

  5. Microbial Primary Productivity in Hydrothermal Vent Chimneys at Middle Valley, Juan de Fuca Ridge

    Science.gov (United States)

    Olins, H. C.; Rogers, D.; Frank, K. L.; Girguis, P. R.; Vidoudez, C.

    2012-12-01

    Chemosynthetic primary productivity supports hydrothermal vent ecosystems, but the extent of that productivity has not been well measured. To examine the role that environmental temperature plays in controlling carbon fixation rates, and to assess the degree to which microbial community composition, in situ geochemistry, and mineralogy influence carbon fixation, we conducted a series of shipboard incubations across a range of temperatures (4, 25, 50 and 90°C) and at environmentally relevant geochemical conditions using material recovered from three hydrothermal vent chimneys in the Middle Valley hydrothermal vent field (Juan de Fuca Ridge). Net rates of carbon fixation (CFX) were greatest at lower temperatures, and were similar among structures. Rates did not correlate with the mineralogy or the geochemical composition of the high temperature fluids at each chimney. No obvious patterns of association were observed between carbon fixation rates and microbial community composition. Abundance of selected functional genes related to different carbon fixation pathway exhibited striking differences among the three study sites, but did not correlate with rates. Natural carbon isotope ratios implicate the Calvin Benson Bassham Cycle as the dominant mechanism of primary production in these systems, despite the abundance of genes related to other pathways (and presumably some degree of activity). Together these data reveal that primary productivity by endolithic communities does not exhibit much variation among these chimneys, and further reveal that microbial activity cannot easily be related to mineralogical and geochemical assessments that are made at a coarser scale. Indeed, the relationships between carbon fixation rates and community composition/functional gene abundance were also likely obfuscated by differences in scale at which these measurements were made. Regardless, these data reveal the degree to which endolithic, anaerobic carbon fixation contributes to

  6. Design and simulation of a geothermal–solar combined chimney power plant

    International Nuclear Information System (INIS)

    Highlights: • A geothermal–solar chimney power plant (GSCPP) is designed and analyzed. • Three different models, viz. full solar model, full geothermal model and geothermal–solar mode are compared. • Power generation under GSM is larger than the sum of FSM and FGM. • GSCPP can effectively solve the continuous operation problem of the SCPP. - Abstract: The solar chimney power plant (SCPP) is dominated by the solar radiation, and therefore its discontinuous operation is an unavoidable problem. In this paper, low temperature geothermal water is introduced into the SCPP for overcoming this problem. Based on a developed transient model, theoretical analyses are carried out to investigate the performance of the geothermal–solar chimney power plant (GSCPP) with main dimensions the same as the Manzanares prototype in Spain. Three operation models, viz. the full solar model, the full geothermal model and the geothermal–solar combined model are compared in typical summer and winter days and throughout the year. It is found that the GSCPP can attractively run in the GSM to deliver power continuously. Due to the ambient-dependant geothermal water outlet temperature, introducing the geothermal water makes greater contribution in winter days than in summer days, in the night than in the daytime. Power generation under GSM is larger than the sum of FSM and FGM. GSM is not the simple superposition of FSM and FGM, but makes better utilization of solar and geothermal energy. In addition, introducing high temperature and mass flow rate geothermal water can doubled and redoubled improve the GSCPP’s power capacity

  7. Vallitalea pronyensis sp nova, isolated from a marine alkaline hydrothermal chimney

    OpenAIRE

    Ben Aissa, F.; Postec, A.; Erauso, G.; Payri, Claude; Pelletier, Bernard; Hamdi, M.; Ollivier, Bernard; Fardeau, Marie-Laure

    2014-01-01

    A novel thermotolerant, anaerobic, Gram-stain-positive, spore-forming bacterium was isolated from a hydrothermal chimney in Prony Bay, New Caledonia. This strain, designated FatNl3(T), grew at 15-55 degrees C (optimum 30 degrees C) and at pH 5.8-8.9 (optimum 7.7). It was slightly halophilic, requiring at least 0.5% NaCl for growth (optimum 2.5-3.0 %), and was able to grow at up to 6% NaCl. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite were not used as terminal electron ...

  8. Early Results of Chimney Technique for Type B Aortic Dissections Extending to the Aortic Arch

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Chen [Affiliated Hospital of Nantong University, Department of General Surgery (China); Tang, Hanfei; Qiao, Tong; Liu, Changjian; Zhou, Min, E-mail: 813477618@qq.com [The Affiliated Hospital of Nanjing University Medical School, Department of Vascular Surgery, Nanjing Drum Tower Hospital (China)

    2016-01-15

    ObjectiveTo summarize our early experience gained from the chimney technique for type B aortic dissection (TBAD) extending to the aortic arch and to evaluate the aortic remodeling in the follow-up period.MethodsFrom September 2011 to July 2014, 27 consecutive TBAD patients without adequate proximal landing zones were retrograde analyzed. Chimney stent-grafts were deployed parallel to the main endografts to reserve flow to branch vessels while extending the landing zones. In the follow-up period, aortic remodeling was observed with computed tomography angiography.ResultsThe technical success rate was 100 %, and endografts were deployed in zone 0 (n = 3, 11.1 %), zone 1 (n = 18, 66.7 %), and zone 2 (n = 6, 22.2 %). Immediately, proximal endoleaks were detected in 5 patients (18.5 %). During a mean follow-up period of 17.6 months, computed tomography angiography showed all the aortic stent-grafts and chimney grafts to be patent. Favorable remodeling was observed at the level of maximum descending aorta and left subclavian artery with expansion of true lumen (from 18.4 ± 4.8 to 25 ± 0.86 mm, p < 0.001 and 27.1 ± 0.62 to 28.5 ± 0.37 mm, p < 0.001) and depressurization of false lumen (from 23.7 ± 2.7 to 8.7 ± 3.8 mm, p < 0.001, from 5.3 ± 1.2 to 2.1 ± 2.1 mm, p < 0.001). While at the level of maximum abdominal aorta, suboptimal remodeling of the total aorta (from 24.1 ± 0.4 to 23.6 ± 1.5 mm, p = 0.06) and true lumen (from 13.8 ± 0.6 to 14.5 ± 0.4 mm, p = 0.08) was observed.ConclusionBased on our limited experience, the chimney technique with thoracic endovascular repair is demonstrated to be promising for TBAD extending to the arch with favorable aortic remodeling.

  9. Replacive sulfide formation in anhydrite chimneys from the Pacmanus hydrothermal field, Papua New Guinea

    Science.gov (United States)

    Los, Catharina; Bach, Wolfgang; Plümper, Oliver

    2016-04-01

    Hydrothermal flow within the oceanic crust is an important process for the exchange of energy and mass between the lithosphere, hydrosphere and biosphere. Infiltrated seawater heats up and interacts with wall rock, causing mineral replacement reactions. These play a large role in the formation of ore deposits; at the discharge zone, a hot, acidic and metal-rich potential ore fluid exits the crust. It mixes with seawater and forms chimneys, built up of sulfate minerals such as anhydrite (CaSO4), which are subsequently replaced by sulfide minerals. Sulfide formation is related to fluid pathways, defined by cracks and pores in the sulfate chimney. Over time, these systems might develop into massive sulfide deposits. The big question is then: how is sulfate-sulfide replacement related to the evolution of rock porosity? To address this question, sulfide-bearing anhydrite chimneys from the Pacmanus hydrothermal field (Manus Basin, Papua New Guinea) were studied using X-ray tomography, EMPA, FIB-SEM and -TEM. The apparently massive anhydrite turns out highly porous on the micro scale, with sulfide minerals in anhydrite cleavage planes and along grain boundaries. The size of the sulfide grains relates to the pores they grew into, suggesting a tight coupling between dissolution (porosity generation) and growth of replacive minerals. Some of the sulfide grains are hollow and apparently used the dissolving anhydrite as a substrate to start growth in a pore. Another mode of sulfide development is aggregates of euhedral pyrite cores surrounded by colloform chalcopyrite. This occurrence implies that fluid pathways have remained open for some time to allow several stages of precipitation during fluid evolution. To start the replacement and to keep it going, porosity generation is crucial. Our samples show that dissolution of anhydrite occurred along pathways where fluid could enter, such as cleavage planes and grain boundaries. It appears that fluids ascending within the inner

  10. Authigenic carbonate crusts and chimneys along the North Anatolian Fault in the Sea of Marmara, Turkey

    Science.gov (United States)

    Yıldız, Güliz; Namık Çaǧatay, M.

    2016-04-01

    The Sea of Marmara is located on the North Anatolian Fault (NAF) fault zone that is a major continental transform plate boundary. It has ca. 1250 m-deep Tekirdag, Central and Cinarcik basins that are separated by two NE-SW trending Central and Western Highs. Extensive cold seeps occur along the active fault segments of the NAF in the deep basins and highs, which are associated with authigenic carbonate crusts, carbonate chimneys and mounds, black sulphidic sediments, and local gas hydrates and oil seepage. The cold seep sites were observed and sampled during the Nautile submersible and Victor 6000 Remotely Operated Vehicle (ROV) dives carried out during MARNAUT and MARSITE cruises in 2007 and 2014, respectively. Here, we report the mineralogical and stable isotopic composition of the authigenic carbonates and discuss their environmental conditions and mechanisms of formation. The carbonate crusts range up to 5 cm in thickness and the chimneys and mounds are up to 2 m high. Some chimneys are active emitting fresh to brackish water at ambient bottom water temperatures (˜ 14° C). The carbonate crusts occur as a pavements, and are commonly covered with black sulphidic sediments and bacterial mats that accommodate a rich chemosynthetic community of bivalves, sea urchins and marine annelid worms (Polychaeta). The authigenic carbonates commonly consist mainly of aragonite, but in a few instances contain subequal amounts of aragonite and calcite. High Mg-calcite is usually a minor to trace component, except in one sample in which it is present as a cement of mudstone. In the active methane emission zones, the sulphate/methane boundary occurs at or close to the seafloor, whereas elsewhere in the Sea of Marmara, the same boundary is located at 2-5 m below the seafloor. This, together with very light stable carbon isotope values (δ13C=-29.8 to - 46.3 ‰ V-PDB), indicates that the anaerobic oxidation of high methane flux emitted from the active faults is the major process

  11. Simulation of solar chimney power plant with an external heat source

    International Nuclear Information System (INIS)

    Solar chimney power plant is a sustainable source of power production. The key parameter to increase the system power output is to increase its size but the plant cannot operate during night hours. This study deals with simulation work to validate results of pilot plant at Manzanares and include the effects of waste heat from a gas turbine power plant in the system. The effects show continuous night operation, a 38.8 percent increase in power at 1000 W/m2 global solar irradiation at daytime and 1.14 percent increase in overall efficiency.

  12. Retrieval columns of SO2 in industrial chimneys using DOAS passive in traverse

    Science.gov (United States)

    Galicia Mejía, Rubén; de la Rosa Vázquez, José Manuel; Sosa Iglesias, Gustavo

    2011-10-01

    The optical Differential Optical Absorption Spectroscopy (DOAS) is a technique to measure pollutant emissions like SO2, from point sources and total fluxes in the atmosphere. Passive DOAS systems use sunlight like source. Measurements with such systems can be made in situ and in real time. The goal of this work is to report the implementation of hardware and software of a portable system to evaluate the pollutants emitted in the atmosphere by industrial chimneys. We show SO2 measurements obtained around PEMEX refinerys in Tula Hidalgo that enables the identification of their pollution degree with the knowledge of speed wind.

  13. Endovascular Aortic Aneurysm Repair with Chimney and Snorkel Grafts: Indications, Techniques and Results

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Rakesh P., E-mail: rpatel9@nhs.net [Northwick Park Hospital, Department of Vascular Radiology (United Kingdom); Katsargyris, Athanasios, E-mail: kthanassos@yahoo.com; Verhoeven, Eric L. G., E-mail: Eric.Verhoeven@klinikum-nuernberg.de [Klinikum Nuernberg, Department of Vascular and Endovascular Surgery (Germany); Adam, Donald J., E-mail: donald.adam@tiscali.co.uk [Heartlands Hospital, Department of Vascular Surgery (United Kingdom); Hardman, John A., E-mail: johnhardman@doctors.org.uk [Royal United Hospital Bath, Department of Vascular Radiology (United Kingdom)

    2013-12-15

    The chimney technique in endovascular aortic aneurysm repair (Ch-EVAR) involves placement of a stent or stent-graft parallel to the main aortic stent-graft to extend the proximal or distal sealing zone while maintaining side branch patency. Ch-EVAR can facilitate endovascular repair of juxtarenal and aortic arch pathology using available standard aortic stent-grafts, therefore, eliminating the manufacturing delays required for customised fenestrated and branched stent-grafts. Several case series have demonstrated the feasibility of Ch-EVAR both in acute and elective cases with good early results. This review discusses indications, technique, and the current available clinical data on Ch-EVAR.

  14. Thermal Analyses of Combined Utilization Process of Seawater by Solar Chimney

    Institute of Scientific and Technical Information of China (English)

    WANG Yiping; FANG Zhenlei; ZHU Li

    2009-01-01

    It is promising to simultaneously develop multiple products through the combined utilization of sea-water by solar chimney technology. A small scale experimental system was set up. The collector temperature, the seawater temperature, and the temperature and humidity of the airflow under the collector were measured. Thermal network analysis of the system was carried out. The results show that the airflow is nearly saturated at the entrance of the chimney, and the mean dry-bulb and wet-bulb temperatures of the airflow have increased by 8.4℃ and 9.6℃ respectively. The radiation heat transfer between the collector and the sky is the biggest heat loss in the system, which is up to 29.1% on average of the solar energy. However, the water evaporation heat is about 23.6% on average of the solar energy. To reduce the heat loss and enhance the water evaporation, it is necessary to reduce the emissivity and thermal conductivity of the collector and increase the evaporation areas.

  15. A novel large filamentous deltaproteobacterium on hydrothermally inactive sulfide chimneys of the Southern Mariana Trough

    Science.gov (United States)

    Kato, Shingo; Yamagishi, Akihiko

    2016-04-01

    Unusual large filamentous bacteria (LFB) have been found on the deep seafloor environments. They play a significant role in geochemical cycling in the dark environments. However, our knowledge of the spatial distribution and phylogenetic diversity of the LFB on the deep seafloor are still limited due to the inaccessibility to these environments. Here, we report the discovery of a novel LFB on a hydrothermally inactive sulfide chimney in a deep-sea hydrothermal field of the Southern Mariana Trough. Light and electron microscopic observation showed that the width and total length of the LFB were >8 μm and >100 μm, respectively, of which morphology was similar to that of other known LFB such as "cable bacteria" of the Desulfobulbaceae. Analyses of a 16S rRNA gene clone library and fluorescence in situ hybridization revealed that this LFB belongs to the Desulfobulbaceae. The 16S rRNA gene of the LFB showed 94% similarity to those of the reported cable bacteria and cultured deltaproteobacterial species, suggesting that the LFB is a novel cable bacterium of the Desulfobulbaceae. The novel LFB potentially play a role in sulfur cycling on sulfide chimneys at the hydrothermally ceasing or even ceased deep-sea hydrothermal fields.

  16. The experimental design of solar heating thermoelectric generator with wind cooling chimney

    International Nuclear Information System (INIS)

    Highlights: • We model an experimental design of thermal electrical generator. • Electrical parameters were collected under the solar radiation. • All the calculated values were obtained from collected data. • Generated power and electrical efficiency were changed by thermal gradient. - Abstract: In this paper we present an experimental design of new solar based thermoelectric generator with wind chimney. Presented generator mainly consists of four parts: a heat pipe with solar collector tube for solar heating, a wind chimney for cooling, a thermoelectric (TE) module for electricity generation and measurement devices-sensors. Presented generator based on experimental design. Aim of this experimental design is to show an alternative way for cheap and efficiently renewable energy producing. The most important features of presented generator are uncomplicated structure, efficiently and cheapness. This experimental design can be improved and used for domestic and commercial application. For this reason, main parts of system can be enhanced and system can be improved. To evaluate of presented generator we collected some experimental data on designed system. Then maximum output power, electrical efficiency and Seebeck coefficient are calculated from obtained data. Results of the measurement are displayed in the form of graphs and tables. Our experiment was carried out on 16th and 21th August, in Samsun, on the north coast of Turkey with the exact location 41°14′N 36°26′E with sea level. Collection of the data was performed from 8:30 a.m. to 4 p.m

  17. Computational fluid dynamics for modeling the turbulent natural convection in a double air-channel solar chimney system

    Science.gov (United States)

    Zavala-Guillén, I.; Xamán, J.; Álvarez, G.; Arce, J.; Hernández-Pérez, I.; Gijón-Rivera, M.

    2016-03-01

    This study reports the modeling of the turbulent natural convection in a double air-channel solar chimney (SC-DC) and its comparison with a single air-channel solar chimney (SC-C). Prediction of the mass flow and the thermal behavior of the SC-DC were obtained under three different climates of Mexico during one summer day. The climates correspond to: tropical savannah (Mérida), arid desert (Hermosillo) and temperate with warm summer (Mexico City). A code based on the Finite Volume Method was developed and a k-ω turbulence model has been used to model air turbulence in the solar chimney (SC). The code was validated against experimental data. The results indicate that during the day the SC-DC extracts about 50% more mass flow than the SC-C. When the SC-DC is located in Mérida, Hermosillo and Mexico City, the air-changes extracted along the day were 60, 63 and 52, respectively. The air temperature at the outlet of the chimney increased up to 33%, 38% and 61% with respect to the temperature it has at the inlet for Mérida, Hermosillo and Mexico City, respectively.

  18. Thermodynamic analysis of a low-temperature waste heat recovery system based on the concept of solar chimney

    International Nuclear Information System (INIS)

    Highlights: • A low grade waste heat recovery system based on the concept of solar chimney is proposed. • The effects of three key factors on the system performance are examined. • Thermodynamics analysis is to find a better way to utilize low grade heat source efficiently. - Abstract: The utilization of low-temperature waste heat draws more and more attention due to serious energy crisis nowadays. This paper proposes a low-temperature waste heat recovery system based on the concept of solar chimney. In the system, low-temperature waste heat is used to heat air to produce an air updraft in the chimney tower. The air updraft propels a turbine fixed at the base of the chimney tower to convert waste heat into electricity. The mathematical model of the system is established based on first law and second law of thermodynamics. Hot water is selected as the representative of low-temperature waste heat sources for researching. The heat source temperature, ambient air temperature and area of heat transfer are examined to evaluate their effects on the system performance such as velocity of updraft, mass flow rate of air, power output, conversion efficiency, and exergy efficiency. The velocity of air demonstrates a better stability than the mass flow rate of air and the pressure difference when temperature of heat source, ambient air temperature or area of heat transfer changes

  19. Biosignatures in chimney structures and sediment from the Loki's Castle low-temperature hydrothermal vent field at the Arctic Mid-Ocean Ridge.

    Science.gov (United States)

    Jaeschke, Andrea; Eickmann, Benjamin; Lang, Susan Q; Bernasconi, Stefano M; Strauss, Harald; Früh-Green, Gretchen L

    2014-05-01

    We investigated microbial life preserved in a hydrothermally inactive silica–barite chimney in comparison with an active barite chimney and sediment from the Loki's Castle low-temperature venting area at the Arctic Mid-Ocean Ridge (AMOR) using lipid biomarkers. Carbon and sulfur isotopes were used to constrain possible metabolic pathways. Multiple sulfur (dδ34S, Δ33S) isotopes on barite over a cross section of the extinct chimney range between 21.1 and 22.5 % in δ34S, and between 0.020 and 0.034 % in Δ33S, indicating direct precipitation from seawater. Biomarker distributions within two discrete zones of this silica–barite chimney indicate a considerable difference in abundance and diversity of microorganisms from the chimney exterior to the interior. Lipids in the active and inactive chimney barite and sediment were dominated by a range of 13C-depleted unsaturated and branched fatty acids with δ13C values between -39.7 and -26.7 %, indicating the presence of sulfur-oxidizing and sulfate-reducing bacteria. The majority of lipids (99.5 %) in the extinct chimney interior that experienced high temperatures were of archaeal origin. Unusual glycerol monoalkyl glycerol tetraethers (GMGT) with 0–4 rings were the dominant compounds suggesting the presence of mainly (hyper-) thermophilic archaea. Isoprenoid hydrocarbons with δ13C values as low as -46 % also indicated the presence of methanogens and possibly methanotrophs.

  20. Prototype implementation and experimental analysis of water heating using recovered waste heat of chimneys

    Directory of Open Access Journals (Sweden)

    Mahmoud Khaled

    2015-03-01

    Full Text Available This work discusses a waste heat recovery system (WHRS applied to chimneys for heating water in residential buildings. A prototype illustrating the suggested system is implemented and tested. Different waste heat scenarios by varying the quantity of burned firewood (heat input are experimented. The temperature at different parts of the WHRS and the gas flow rates of the exhaust pipes are measured. Measurements showed that the temperature of 95 L tank of water can be increased by 68 °C within one hour. Obtained results show that the convection and radiation exchanges at the bottom surface of the tank have a considerable impact on the total heat transfer rate of the water (as high as 70%.

  1. Efficiency enhancement of wood stove integrated with catalytic combustor and modified chimney

    Directory of Open Access Journals (Sweden)

    G. Murali

    2014-12-01

    Full Text Available Domestic wood combustion produces smoke that is harmful to human health and increases fine particle level in the atmosphere. Some necessary changes in the design are essential in the domestic wood stove in order to improve the performance and scale down the emission. In this work, an improved wood stove integrated with the catalytic combustor and modified chimney that uses wood as fuel has been experimentally evaluated. Water boiling test, cooking test and emission test have been conducted to evaluate the performance of the stove. It was observed that emission has been considerably controlled because of the incorporation of catalytic combustor. The heat losses through the walls of stove decresed by providing ceramic insulation. The thermal efficiency value of an improved wood stove obtained was 41.18% and this is 31.52% higher than traditional stove. The improved wood stove results better performance than a traditional wood stove.

  2. Mackinawite and greigite in ancient alkaline hydrothermal chimneys: Identifying potential key catalysts for emergent life

    Science.gov (United States)

    White, Lauren M.; Bhartia, Rohit; Stucky, Galen D.; Kanik, Isik; Russell, Michael J.

    2015-11-01

    One model for the emergence of life posits that ancient, low temperature, submarine alkaline hydrothermal vents, partly composed of iron-sulfides, were capable of catalyzing the synthesis of prebiotic organic molecules from CO2, H2 and CH4. Specifically, hydrothermal mackinawite (FeIIS) and greigite (FeIIFeIII2S4) have been highlighted in previous studies as analogs of the active centers of hydrogenase, ferredoxin, acetyl coenzyme-A synthase and carbon monoxide dehydrogenase featured in the biochemistry of certain autotrophic prokaryotes that occupy the base of the evolutionary tree. Despite the proposed importance of iron sulfide minerals and clusters in the synthesis of abiotic organic molecules, the mechanisms for the formation of these sulfides from solution and their preservation under the anoxic and low temperature (below 100 °C) conditions expected in off-axis submarine alkaline vent systems is not well understood (Bourdoiseau et al., 2011; Rickard and Luther, 2007). To rectify this, single hydrothermal chimneys were precipitated using a unique apparatus to simulate growth at hydrothermal vents of moderate temperature under supposed Hadean ocean-bottom conditions. Iron sulfide phases were observed through Raman spectroscopy at growth temperatures ranging from 40° to 80 °C. Fe(III)-containing mackinawite is confirmed to be present with mackinawite and greigite, supporting an FeIII-mackinawite intermediate mechanism for the transformation of mackinawite to greigite below 100 °C. Raman spectroscopy of the chimneys revealed a maximum yield of greigite at 75 °C. These results suggest abiotic production of catalytically active mackinawite and greigite are possible under early Earth hydrothermal conditions as well as on other wet, rocky worlds geochemically similar to the Earth.

  3. Origin of pockmarks and chimney structures on the flanks of the Storegga Slide, offshore Norway

    Science.gov (United States)

    Paull, C.K.; Ussler, W., III; Holbrook, W.S.; Hill, T.M.; Keaten, R.; Mienert, J.; Haflidason, H.; Johnson, J.E.; Winters, W.J.; Lorenson, T.D.

    2008-01-01

    Seafloor pockmarks and subsurface chimney structures are common on the Norwegian continental margin north of the Storegga Slide scar. Such features are generally inferred to be associated with fluid expulsion, and imply overpressures in the subsurface. Six long gravity and piston cores taken from the interior of three pockmarks were compared with four other cores taken from the same area but outside the pockmarks, in order to elucidate the origins and stratigraphy of these features and their possible association with the Storegga Slide event. Sulfate gradients in cores from within pockmarks are less steep than those in cores from outside the pockmarks, which indicates that the flux of methane to the seafloor is presently smaller within the pockmarks than in the adjacent undisturbed sediments. This suggests that these subsurface chimneys are not fluid flow conduits lined with gas hydrate. Methane-derived authigenic carbonates and Bathymodiolus shells obtained from a pockmark at >6.3 m below the seafloor indicate that methane was previously available to support a chemosynthetic community within the pockmark. AMS 14C measurements of planktonic Foraminifera overlying and interlayered with the shell-bearing sediment indicate that methane was present on the seafloor within the pockmark prior to 14 ka 14C years B.P., i.e., well before the last major Storegga Slide event (7.2 ka 14C years B.P., or 8.2 ka calendar years B.P.). These observations provide evidence that overpressured fluids existed within the continental margin sediments off Norway during the last major advance of Pleistocene glaciation. ?? Springer-Verlag 2007.

  4. Metal sources of black smoker chimneys, Endeavour Segment, Juan de Fuca Ridge: Pb isotope constraints

    Energy Technology Data Exchange (ETDEWEB)

    Yao Huiqiang, E-mail: hqyao11@yahoo.com [Guangzhou Institute of Geochemistry Chinese Academy of Science, Guangzhou 510640 (China); National Key Lab of Marine Geology, Tongji University, Shanghai 200092 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhou Huaiyang, E-mail: zhouhy@tongji.edu.cn [Guangzhou Institute of Geochemistry Chinese Academy of Science, Guangzhou 510640 (China); National Key Lab of Marine Geology, Tongji University, Shanghai 200092 (China); Peng Xiaotong [Guangzhou Institute of Geochemistry Chinese Academy of Science, Guangzhou 510640 (China); National Key Lab of Marine Geology, Tongji University, Shanghai 200092 (China); Bao Shenxu [Guangzhou Institute of Geochemistry Chinese Academy of Science, Guangzhou 510640 (China); National Key Lab of Marine Geology, Tongji University, Shanghai 200092 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Wu Zijun; Li Jiangtao [Guangzhou Institute of Geochemistry Chinese Academy of Science, Guangzhou 510640 (China); National Key Lab of Marine Geology, Tongji University, Shanghai 200092 (China); Sun Zhilei; Chen Zhiqiang; Li Jiwei [Guangzhou Institute of Geochemistry Chinese Academy of Science, Guangzhou 510640 (China); National Key Lab of Marine Geology, Tongji University, Shanghai 200092 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Chen Guangqian [Guangzhou Institute of Geochemistry Chinese Academy of Science, Guangzhou 510640 (China)

    2009-10-15

    Hydrothermal chimney sulfides, vent cap chimney samples, Fe-oxide and basalts from sediment-starving Juan de Fuca Ridge, in the Endeavour segment, exhibit a range of Pb isotope ratios ({sup 206}Pb/{sup 204}Pb = 18.658-18.769; {sup 207}Pb/{sup 204}Pb = 15.457-15.566; {sup 208}Pb/{sup 204}Pb = 37.810-38.276). The data array is not parallel to the northern hemisphere mantle reservoirs indicating a possible sediment component within the sulfides. By assuming that the potential end-member sediment component has a {sup 207}Pb/{sup 204}Pb (15.70) similar to Middle Valley sediment, it is suggested the potential end-member sediment component may have {sup 206}Pb/{sup 204}Pb = 18.90; {sup 208}Pb/{sup 204}Pb = 38.82. Basalt-derived Pb for the Endeavour segment hydrothermal system involves about 50/50 leaching of E-MORB and T2-MORB. Detailed observations show the Mothra field derives more Pb from T2-MORB than the Main Endeavour field does. According to the binary mixing model, the results show little Pb (<1.5%) or no Pb derivation from sedimentary sources. However, the high NH{sub 4}{sup +}, CH{sub 4} and Br/Cl ratios in hydrothermal fluids are consistent with a sediment component within the segment. Reconciling the Pb isotope data with the chemistry data of hydrothermal fluids, it is suggested that the sediment component may be located in a lower temperature recharge zone where Pb could not be mobilized from the sediment.

  5. Determining real temperature of steel chimney surface using thermograpy method. (Polish Title: Wyznaczenie rzeczywistej temperatury powierzchni kominów stalowych metodą termograficzną)

    Science.gov (United States)

    Wróbel, Anna; Wróbel, Andrzej

    2013-12-01

    Assembly and technical evaluation of a steel chimney both require determining shape of its axis. Because permissible deflection of the top of a steel chimney shaft relative to the base according to the PN-B-06200 norm is: 30 mm when height 50 m, geodetic measurements should be performed with high accuracy. Additionally, the measurements should be performed when deflection of the chimney is not influenced by sun and wind. Deflection measured in a sunny weather is influenced by elastic deflection caused by uneven temperature distribution in the chimney shaft. In practice, the measurements should be done before the sunrise or on a cloudy day. However, during chimney assembly it is often not possible to choose conditions of measurement. For steel chimneys of cylindrical shape without thermal insulation inside, the direction of elastic deflection is not very different from the direction of sun's rays, and its value can be calculated from dimensions of the chimney and temperature differences on its circumference. The problem discussed in this article is measuring the real temperature of the outer surface of a chimney in a possibly fast and accurate way. Thermography allows acquiring the surface temperature distribution quickly (in a few minutes). The accuracy of the measured values is influenced by: emissivity coefficient of the chimney surface, air temperature and humidity and background temperature. The biggest problem is determining background temperature if the surroundings consist of a few objects with different temperatures. The equivalent background temperature was determined from thermo graphic and contact temperature measurements of a specially prepared sample. The sample was produced from the same material as the steel chimney, covered with the same paint and the measurements were performed near the chimney, so the surroundings were similar to the surroundings of the chimney. Conducted experiment shows that on a sunny day the background temperature cannot be

  6. Endovascular Aneurysm Repair Using a Reverse Chimney Technique in a Patient With Marfan Syndrome and Contained Ruptured Chronic Type B Dissection

    International Nuclear Information System (INIS)

    We report endovascular thoracic and abdominal aneurysm repair (EVAR) with reverse chimney technique in a patient with contained ruptured type B dissection. EVAR seems feasible as a bailout option in Marfan patients with acute life-threatening disease.

  7. Experiments of chimney flows for the validation of the behaviour of passive autocatalytic recombiners; Experimente zur Validierung eines Kaminmodells fuer die Simulation des Betriebsverhaltens eines Wasserstoffrekombinators

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Berno [RWTH Aachen Univ. (Germany). Lehrstuhl fuer Reaktorsicherheit und -technik (LRST)

    2013-10-15

    For the validation of the computational code REKO-DIREKT simulating the operational behaviour of passive autocatalytic recombiners in severe accidents, experiments on chimney flows were performed in cooperation between RWTH Aachen and Forschungszentrum Juelich. This compact describes the experimental setup and shows the correlation between the H{sub 2} concentration, the catalyst temperature and the inlet velocity at various recombiner chimney heights. (orig.)

  8. Microbial life associated with low-temperature hydrothermal venting and formation of barite chimneys at Loki's Castle vent field

    Science.gov (United States)

    Thorseth, I. H.; Steen, I.; Roalkvam, I.; Dahle, H.; Stokke, R.; Rapp, H.; Pedersen, R.

    2010-12-01

    A low-temperature diffuse venting area with numbers of small barite chimneys is located on the flank of the large sulphide mound of the Loki’s Castle black smoker vent field at the Arctic Mid-Ocean Ridge (AMOR). White cotton-like microbial mats on top of the barite chimneys and associated siboglinid tubeworms were observed. The temperature was determined to 20°C for the surface sediment and 0°C for the white microbial mats, just above the ambient bottom seawater temperature of -0.8°C. The microbial mats were sampled using a remote operating vehicle (ROV) equipped with a hydraulic sampling cylinder (biosyringe) and the chimneys using an aluminum scuffle box. Black colored interior flow channels surrounded by white outer sections of nearly pure barite, were observed. Scanning electron microscopy (SEM) of mats showed numerous microbial cells and large amounts of extracellular thread-like material with attached barite crystals. Inside the chimneys microbial cells are partially embedded in barite, and individual crystals are also frequently covered by extracellular material. The microbial activity could thus have an important influence on the nucleation and growth of the barite crystals and thus on the formation of the chimneys. To reveal the microbial community structure, 16S rRNA gene sequence tag-encoded pyrosequencing (1.1 x 104 - 3.5 x 104 amplicons per library) followed by taxonomic classification of the reads using the MEGAN software, were performed. Organisms assigned to a genus of sulfide oxidizers (Sulfurimonas) within the e-Proteobacteria were abundant in each chimney structure; the white microbial mats (86-96% of the reads), the white barite (36% of total reads); the black flow channel (9.9%). The second most dominating taxon in the white chimney barite, including 26% of the reads, was anaerobic methanotrophs (ANME) of the ANME-1 clade, indicating anaerobic methane oxidation (AOM) as a major microbial process. Furthermore, the novel AOM associated clade

  9. Soil-Structure Interaction Analysis of Tall Reinforced Concrete Chimney with Piled Raft and Annular Raft under Along-Wind Load

    Directory of Open Access Journals (Sweden)

    B. R. Jayalekshmi

    2013-01-01

    Full Text Available A three-dimensional (3D soil-structure interaction (SSI analysis of 300 m high reinforced concrete chimneys having piled annular raft and annular raft foundations subjected to along-wind load is carried out in the present study. To understand the significance of SSI, four types of soils were considered based on their flexibility. The effect of stiffness of the raft was evaluated using three different ratios of external diameter to thickness of the annular raft. The along-wind load was computed according to IS:4998 (Part 1-1992. The integrated chimney-foundation-soil system was analysed by commercial finite element (FE software ANSYS, based on direct method of SSI assuming linear elastic behaviour. FE analyses were carried out for two cases of SSI (I chimney with annular raft foundation and (II chimney with piled raft foundation. The responses in chimney such as tip deflection, bending moments, and base moment and responses in raft such as bending moments and settlements were evaluated for both cases and compared to that obtained from the conventional method of analysis. It is found that the responses in chimney and raft depend on the flexibility of the underlying soil and thickness of the raft.

  10. Magnetite formation from ferrihydrite by hyperthermophilic archaea from Endeavour Segment, Juan de Fuca Ridge hydrothermal vent chimneys.

    Science.gov (United States)

    Lin, T Jennifer; Breves, E A; Dyar, M D; Ver Eecke, H C; Jamieson, J W; Holden, J F

    2014-05-01

    Hyperthermophilic iron reducers are common in hydrothermal chimneys found along the Endeavour Segment in the northeastern Pacific Ocean based on culture-dependent estimates. However, information on the availability of Fe(III) (oxyhydr) oxides within these chimneys, the types of Fe(III) (oxyhydr) oxides utilized by the organisms, rates and environmental constraints of hyperthermophilic iron reduction, and mineral end products is needed to determine their biogeochemical significance and are addressed in this study. Thin-section petrography on the interior of a hydrothermal chimney from the Dante edifice at Endeavour showed a thin coat of Fe(III) (oxyhydr) oxide associated with amorphous silica on the exposed outer surfaces of pyrrhotite, sphalerite, and chalcopyrite in pore spaces, along with anhydrite precipitation in the pores that is indicative of seawater ingress. The iron sulfide minerals were likely oxidized to Fe(III) (oxyhydr) oxide with increasing pH and Eh due to cooling and seawater exposure, providing reactants for bioreduction. Culture-dependent estimates of hyperthermophilic iron reducer abundances in this sample were 1740 and 10 cells per gram (dry weight) of material from the outer surface and the marcasite-sphalerite-rich interior, respectively. Two hyperthermophilic iron reducers, Hyperthermus sp. Ro04 and Pyrodictium sp. Su06, were isolated from other active hydrothermal chimneys on the Endeavour Segment. Strain Ro04 is a neutrophilic (pH opt 7-8) heterotroph, while strain Su06 is a mildly acidophilic (pH opt 5), hydrogenotrophic autotroph, both with optimal growth temperatures of 90-92 °C. Mössbauer spectroscopy of the iron oxides before and after growth demonstrated that both organisms form nanophase (hydrothermal systems that are mildly acidic where mineral weathering at increased temperatures occurs. PMID:24612368

  11. The Inventory Of High Objects Applying Laser Scanning, Focus On The Cataloguing A Reinforced Concrete Industrial Chimney

    Science.gov (United States)

    Gawałkiewicz, Rafał

    2015-12-01

    There are many surveying methods to measure the inclination of a chimney with the use of classical protractor instruments (Theo 010A/B, T2 Wild), electronic theodolites (TC2002 Wild-Leica), electronic total stations, including mirrorless ones, allowing to define indirectly the course of the construction's axis on the selected observation levels. The methods are the following: indentations, direct projection, double-edged method, polar method with the option of mirrorless measurement. At the moment a very practical and quick measurement technology, significantly eliminating the influence of human errors on the observation results, is laser scanning. The article presents the results of the scanning of 120-metres high reinforced concrete industrial chimney of the Cement Plant "Ożarów", with the application of modern scanning total station VX Spatial Station by Trimble, as an alternative to the methods applied so far. The advantage of scanning is the possibility to obtain a point cloud, which, apart from the information on the course of the chimney axis in the space, provides detail information on the real shape and deformations of the coating of the object's core.

  12. Dioxin emissions from coal combustion in domestic stove: Formation in the chimney and coal chlorine content influence

    Directory of Open Access Journals (Sweden)

    Paradiz Bostjan

    2015-01-01

    Full Text Available Combustion experiments conducted in domestic stove burning hard coal demonstrated a predominant influence of the coal chlorine content on the PCDD/F emissions, together with a pronounced effect of the flue gas temperature. PCDD/F concentrations of over 100 ng TEQ/m3, three orders of magnitude higher than in a modern waste incinerator, were measured in the flue gases of a domestic stove when combusting high chlorine coal (0.31 %. The PCDD/F concentrations in the flue gases dropped below 0,5 ng TEQ/m3, when low chlorine coal (0.07 % was used. When low chlorine coal was impregnated with NaCl to obtain 0.38 % chlorine content, the emission of the PCDD/Fs increased by two orders of magnitude. Pronounced nonlinearity of the PCDD/F concentrations related to chlorine content in the coal was observed. The combustion of the high chlorine coal yielded PCDD/F concentrations in flue gases one order of magnitude lower in a fan cooled chimney when compared to an insulated one, thus indicating formation in the chimney. The influence of flue gas temperature on the PCDD/F emissions was less pronounced when burning low chlorine coal. The predominant pathway of the PCDD/F emissions is via flue gases, 99 % of the TEQ in the case of the high chlorine coal for insulated chimney.

  13. Phylogenetic diversity of nitrogen-utilizing genes in hydrothermal chimneys from 3 middle ocean ridges.

    Science.gov (United States)

    Cao, Huiluo; Shao, Zongze; Li, Jiangtao; Zhang, Weipeng; Qian, Pei-Yuan

    2015-11-01

    Nitrogen-metabolizing genes, including nitrogenase (nifH), periplasmic nitrate reductase (napA), and cytochrome cd 1-type nitrite reductase (nirS), were collected from hydrothermal chimney sulfides on 3 middle ocean ridges and compared for the first time. There was a clear phylogenetic distinction of these nifH genes between different hydrothermal ecosystems, which supported the colonization and potential adaptation by different nitrogen fixing microbes in those sulfides. In particular, in sulfides from low-temperature hydrothermal vents of the Southwest Indian Ocean Ridge, the prevalence of nifH genes appears to be attributed to sulfate-reducing bacteria, suggesting their ecological significance. Phylogenetic analysis of nitrate/nitrite reductase genes indicated that nitrate was a critical electron acceptor for sulfur- or metal-oxidizing bacteria in these hydrothermal ecosystems. Our results provided information about the compositions and diversity of the 3 important genes involved in nitrogen fixation and nitrate/nitrite reduction processes in hydrothermal ecosystems and is the first comprehensive genetic repertoire of genes related to potential nitrogen fixation and denitrification processes in various hydrothermal environments.

  14. Free release waste characterisation during the decommissioning of windscale Pile 2 Chimney

    Energy Technology Data Exchange (ETDEWEB)

    Frith, A.J. [NIRAS (United Kingdom); Dickson, E.D.; Hewetson, J.A.; McCormick, K. [BNFL (United Kingdom)

    2003-07-01

    The decommissioning of windscale Pile 2 Chimney resulted in the removal of one of most historically significant and prominent features of the Sellafield site. The project was the first large scale concrete ''free release'' operation to be undertaken on the Sellafield nuclear site, producing 4500 tons of concrete of which 3000 tons was demonstrated to be ''free release''. The paper describes the radiometric techniques employed in the characterisation and segregation of the concrete into low level waste (LLW), very low level waste (VLLW) and free release categories. It examines the robust solutions that were developed to meet the technical and regulatory challenges of the project, which included the definition of free release, the selection of averaging volumes, the testing and validation of the monitoring systems employed for ton quantities of concrete and the identification and removal of small numbers of fuel particles from the free release waste stream. As a result of interest shown by other BNFL and UKAEA decommissioning projects at Sellafield, the paper finishes by discussing ways in which the system may be developed to assay other waste streams. (orig.)

  15. Novel insights into methane cycling, lateral gene transfer, and the rare biosphere within carbonate chimneys of the Lost City Hydrothermal Field (Invited)

    Science.gov (United States)

    Brazelton, W. J.; Ludwig, K. A.; Schrenk, M. O.; Kelley, D. S.; Sogin, M. L.; Baross, J. A.

    2010-12-01

    The Lost City Hydrothermal Field, an ultramafic-hosted system located 15 km west of the Mid-Atlantic Ridge, has experienced at least 30,000 years of hydrothermal activity. Previous studies have shown that its carbonate chimneys form by mixing of ~90°C, pH 9-11 hydrothermal fluids and cold seawater. Flow of methane and hydrogen-rich hydrothermal fluids through the carbonate chimneys supports dense microbial biofilm communities. This presentation will describe recent studies using new techniques that have provided greater insight into the microbial ecology and biogeochemistry of Lost City chimneys. We have investigated the archaeal and bacterial communities of Lost City carbonate chimneys that vary in age between ~30 and ~1200 years, as determined by U-Th isotope systematics. Using next-generation pyrosequencing technology, we collected >200,000 sequences of the V6 region of 16S rRNA genes. This extremely deep sequencing effort enabled detection of very rare organisms as well as abundant organisms detected by previous studies. The taxonomic composition of the archaeal and bacterial communities clearly differed in chimneys of different ages, and many of the rare sequences in young chimneys were more abundant in older chimneys, indicating that members of the rare biosphere can become dominant members of the ecosystem when environmental conditions change. These results suggest that a long history of selection over many cycles of chimney growth has resulted in numerous closely related species at Lost City, each of which is pre-adapted to a particular set of re-occurring environmental conditions. In this model, the rare biosphere can be considered a repository for genes that are not currently advantageous but have been in the past and may be again in the future. Interestingly, metagenomic sequencing at Lost City has indicated the potential for frequent lateral gene transfer among organisms inhabiting the chimney biofilms. Specifically, the Lost City metagenomic dataset

  16. U-Th systematics and 230Th ages of carbonate chimneys at the Lost City Hydrothermal Field

    Science.gov (United States)

    Ludwig, Kristin A.; Shen, Chuan-Chou; Kelley, Deborah S.; Cheng, Hai; Edwards, R. Lawrence

    2011-04-01

    The Lost City Hydrothermal Field (LCHF) is a serpentinite-hosted vent field located 15 km west of the spreading axis of the Mid-Atlantic Ridge. In this study, uranium-thorium (U-Th) geochronological techniques have been used to examine the U-Th systematics of hydrothermal fluids and the 230Th ages of hydrothermally-precipitated carbonate chimneys at the LCHF. Fluid sample analyses indicate that endmember fluids likely contain only 0.0073 ng/g U or less compared to 3.28 ± 0.03 ng/g of U in ambient seawater. For fluid samples containing only 2-21% ambient seawater (1.1-11 mmol/kg Mg), Th concentration is 0.11-0.13 pg/g and surrounding seawater concentrations average 0.133 ± 0.016 pg/g. The 230Th/ 232Th atomic ratios of the vent fluids range from 1 (±10) × 10 -6 to 11 (±5) × 10 -6, are less than those of seawater, and indicate that the vent fluids may contribute a minor amount of non-radiogenic 230Th to the LCHF carbonate chimney deposits. Chimney 238U concentrations range from 1 to 10 μg/g and the average chimney corrected initial δ 234U is 147.2 ± 0.8, which is not significantly different from the ambient seawater value of 146.5 ± 0.6. Carbonate 232Th concentrations range broadly from 0.0038 ± 0.0003 to 125 ± 16 ng/g and 230Th/ 232Th atomic ratios vary from near seawater values of 43 (±8) × 10 -6 up to 530 (±25) × 10 -3. Chimney ages, corrected for initial 230Th, range from 17 ± 6 yrs to 120 ± 13 kyrs. The youngest chimneys are at the intersection of two active, steeply-dipping normal faults that cut the Atlantis Massif; the oldest chimneys are located in the southwest portion of the field. Vent deposits on a steep, fault-bounded wall on the east side of the field are all <4 kyrs old, indicating that mass wasting in this region is relatively recent. Comparison of results to prior age-dating investigations of submarine hydrothermal systems shows that the LCHF is the most long-lived hydrothermal system known to date. It is likely that seismic

  17. Microbial carbon cycling in Lost City hydrothermal chimneys and other serpentinite-hosted ecosystems (Invited)

    Science.gov (United States)

    Brazelton, W. J.; Lang, S. Q.; Morrill, P. L.; Twing, K. I.; Crespo-Medina, M.; Morgan-Smith, D.; Früh-Green, G. L.; Schrenk, M. O.

    2013-12-01

    Ultramafic rocks formed in the Earth's mantle and uplifted into the crust represent an immense but poorly described reservoir of carbon. The biological availability of this rock-hosted carbon reservoir is unknown, but the set of geochemical reactions known as serpentinization can mobilize carbon from the subsurface and trigger the growth of dense microbial communities. Serpentinite-hosted ecosystems such as the chimney biofilms of the Lost City hydrothermal field can support dense populations of bacteria and archaea fueled by the copious quantities of H2 and methane (CH4) released by serpentinization (1-5). The metabolic pathways involved, however, remain unknown, and conventional interpretations of genomic and experimental data are complicated by the unusual carbon speciation in these environments. Carbon dioxide is scarce due to the highly reducing, high pH conditions. Instead, the predominant forms of carbon are CH4 and formate (5). Despite its natural abundance, however, direct evidence for CH4-derived biomass is lacking (1,4,5), and the role of formate is potentially significant but largely unexplored (1,5). To gain a more generalized perspective of carbon cycling in serpentinite-hosted ecosystems, we have recently investigated fluids and rocks collected from serpentinizing ophiolites in California, Canada, and Italy. Our results point to potentially H2-utilizing, autotrophic Betaproteobacteria thriving in shallow, oxic-anoxic transition zones and anaerobic Clostridia inhabiting anoxic, subsurface zones (1,6). The carbon sources utilized by the Clostridia are unknown, but preliminary metagenomic evidence is consistent with a fermentation-style metabolic strategy that may be conducive to an oxidant-limited, subsurface environment. Curiously, despite the abundance of H2 and CH4 in these continental springs, none of the geochemical, genomic, or experimental results obtained thus far contain any evidence for biological methanogenesis (1,6). This is in stark

  18. Application of Solar Chimney Concept to Solve Potential Safety Issues of Nuclear Power Plants

    International Nuclear Information System (INIS)

    In this paper two main events and their causes have been investigated and a potential alternative supporting system will be provided. The first event to be addressed is the Station Blackout (SBO) caused by the inherent unreliability of the Emergency Diesel Generators (EDGs) and Alternative AC (AAC) power sources. Different parameters affect The EDG unreliability; for instance, mechanical, operational, maintenance and surveillance. Those parameters will be analyzed and linked to plant safety and Core Damage Frequency (CDF). Also the AACs, the SBO diesel generators, will be studied and their operational requirements similarity with the EDGs will be discussed. The second event to be addressed is the Loss of Ultimate Heat Sink (LUHS) caused by the degradation of heat exchange effectiveness, that is, the poor heat transfer to the Ultimate Heat Sink (UHS). Different causes to such case were observed; intake lines blockages due to ice and foreign biological matters formation and oil spill near the heat sink causing the oil leakage to the heat exchangers tubes. The later cause, oil spill, has been given a special attention here due its potential effects for different nuclear power plants (NPPs) around the world; for example, Finland and the United Arab Emirates (UAE). For the Finnish case, the Finnish nuclear regulator (STUK) took already countermeasures for such scenario by introducing alternative heat sink, cooling towers, for the primary used heat sink, sea water, for one of its nuclear power plants. The abundance of the solar irradiation in the UAE region provides a perfect condition for the implementation of solar power applications. Utilizing this unique characteristic of that region may provide promising alternative and diverse options for solving potential safety related issues of their NPPs. The Solar Chimney Power Plant (SCPP) could be employed to serve as a supporting system to provide emergency power, in the case of SBO, and emergency cooling, in the case of

  19. Application of Solar Chimney Concept to Solve Potential Safety Issues of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Khasawneh, Khalid; PARK, Youn Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    In this paper two main events and their causes have been investigated and a potential alternative supporting system will be provided. The first event to be addressed is the Station Blackout (SBO) caused by the inherent unreliability of the Emergency Diesel Generators (EDGs) and Alternative AC (AAC) power sources. Different parameters affect The EDG unreliability; for instance, mechanical, operational, maintenance and surveillance. Those parameters will be analyzed and linked to plant safety and Core Damage Frequency (CDF). Also the AACs, the SBO diesel generators, will be studied and their operational requirements similarity with the EDGs will be discussed. The second event to be addressed is the Loss of Ultimate Heat Sink (LUHS) caused by the degradation of heat exchange effectiveness, that is, the poor heat transfer to the Ultimate Heat Sink (UHS). Different causes to such case were observed; intake lines blockages due to ice and foreign biological matters formation and oil spill near the heat sink causing the oil leakage to the heat exchangers tubes. The later cause, oil spill, has been given a special attention here due its potential effects for different nuclear power plants (NPPs) around the world; for example, Finland and the United Arab Emirates (UAE). For the Finnish case, the Finnish nuclear regulator (STUK) took already countermeasures for such scenario by introducing alternative heat sink, cooling towers, for the primary used heat sink, sea water, for one of its nuclear power plants. The abundance of the solar irradiation in the UAE region provides a perfect condition for the implementation of solar power applications. Utilizing this unique characteristic of that region may provide promising alternative and diverse options for solving potential safety related issues of their NPPs. The Solar Chimney Power Plant (SCPP) could be employed to serve as a supporting system to provide emergency power, in the case of SBO, and emergency cooling, in the case of

  20. Vallitalea pronyensis sp. nov., isolated from a marine alkaline hydrothermal chimney.

    Science.gov (United States)

    Ben Aissa, Fatma; Postec, Anne; Erauso, Gaël; Payri, Claude; Pelletier, Bernard; Hamdi, Moktar; Ollivier, Bernard; Fardeau, Marie-Laure

    2014-04-01

    A novel thermotolerant, anaerobic, Gram-stain-positive, spore-forming bacterium was isolated from a hydrothermal chimney in Prony Bay, New Caledonia. This strain, designated FatNI3(T), grew at 15-55 °C (optimum 30 °C) and at pH 5.8-8.9 (optimum 7.7). It was slightly halophilic, requiring at least 0.5 % NaCl for growth (optimum 2.5-3.0 %), and was able to grow at up to 6 % NaCl. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite were not used as terminal electron acceptors. Growth of strain FatNI3(T) was inhibited in the presence of sulfite (2 mM) or nitrite (2 mM). Strain FatNI3(T) fermented cellobiose, glucose, mannose, maltose, sucrose, galactose, lactose, ribose, fructose, rhamnose, raffinose, xylose, yeast extract, peptone and biotrypticase. The main fermentation products from glucose metabolism were acetate, ethanol, H2 and CO2. The predominant cellular fatty acids were iso-C15 : 0 and anteiso-C15 : 0. The main polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, and unknown glycolipids and phospholipids. The G+C content of the genomic DNA was 36.6 mol%. On the basis of phylogenetic and physiological properties, strain FatNI3(T) ( = DSM 25904 = JCM 18391) belonging to the phylum Firmicutes, class Clostridia, order Clostridiales, is proposed as the type strain of a novel species of the genus Vallitalea, for which the name Vallitalea pronyensis sp. nov. is proposed. PMID:24408522

  1. Geochemical studies on the biodiversity and hydrothermal activity; mineralogy, chemistry, and age determination of hydrothermal chimney collected from Suiyo seamount, Izu-Bonin arc

    Science.gov (United States)

    Noguchi, T.; Oomori, T.; Taira, N.; Takada, J.; Urabe, T.

    2004-12-01

    Hydrothermal chimney structure has the steep environmental gradients of temperature, redox potential, pH and chemical concentration, which will provide diverse microhabitats for microbial communities (K.Takai et al. 2001, Hermie J.M. Harmsen et al. 1997). It is important for detailed understanding of the biodiversity to determine the chimney structural environment. Suiyo seamount is located 28.57° N, 140.66° E, where is suitable to compare with the Mid-ocean ridge hydrothermal field, because of few influence of terrestrial sediment. It was reported that the magma chamber below the seamount was very shallow ( ˜1 km), and high temperature hydrothermal fluid chamber was underlying just below the seafloor sealed with anhydrite and barite. Chimney samples used in this study were collected by Dive 1222-1225 of SHINKAI 2000 (JAMSTEC) in 2000. We measured the chemical composition with neutron activation analysis (NAA) and X-ray fluorescence analysis (XRF), mineral composition with X-ray diffraction analysis (XRD), and the precipitation age measurements ( ˜200 years) of these chimneys with γ -ray spectrometry (210Pb/Pb method, 228Th/228Ra method, and 210Pb/226Ra method). The mineral composition of the Suiyo seamount chimney were contained barite (BaSO4), sphalerite ((Zn,Fe)S), pyrite (FeS2), and chalcopyrite (CuFeS2) as a major mineral constituents. The chemical composition shows that gold contents in the chimney collected from Suiyo seamount were much higher (maximum 166 ppm) than other hydrothermal field. The chronological study showed that the precipitation ages of sulfide chimney samples (ranged in 37.2-79.6 years before 2002 by 210Pb/Pb method) were older than barite chimney ((ranged in 2.9-8.2 years before 2002 by 228Th/228Ra method). We will discuss about the process of chimney formation, the temporal variation of the past hydrothermal activity and the difference from other submarine hydrothermal fields (EPR, MAR, Okinawa trough, Loihi seamount).

  2. Numerical investigation on the enhancement capability of annular chimney towards natural convective heat transfer in the interior zone of scaled down FBR core catcher

    International Nuclear Information System (INIS)

    Full text of publication follows: A numerical study has been carried out to determine the influence of annular cylindrical chimney on buoyancy-induced flow in the dished end cavity of scaled down Fast Breeder Reactor. Results are presented for (i) cylindrical chimney configuration and (ii) annular chimney configuration occupying the center of the circular plate. Two dimensional laminar simulations are obtained by solving the fully elliptical governing equations of flow and energy. The fluid is Newtonian and incompressible and satisfies the Boussinesq approximation. Results for the upward facing isothermal circular plate with chimney configurations in confined enclosure are analyzed. The velocity fields and isotherms are studied extensively to assess the impact of both geometries on the flow structure, dynamics and overall heat transfer characteristics in the cavity, towards enhancement of natural convective heat transfer. The predicted results for the cylindrical chimney are compared with known experimental results. The results are of interest to post accident heat removal in fast breeder reactors (FBR). (authors)

  3. Development of a practical training program based on BNL`s input to new NFPA Lined Masonary Chimney Venting Tables

    Energy Technology Data Exchange (ETDEWEB)

    Potter, G. [Agway Energy Products, Tully, NJ (United States)

    1997-09-01

    This paper describes how we developed a practical training program for technicians and sales personnel from the BNL studies that evolved into the Lined Chimney Venting Tables. One of the topics discussed is our search for solutions to the reoccurring problems associated with flue gas condensation on newly installed oil fired appliances. The paper will also discuss our own experiences in applying the new venting tables and working through the questions that arise when we encounter installations beyond the scope of the present tables.

  4. Endovascular Treatment of a Symptomatic Thoracoabdominal Aortic Aneurysm by Chimney and Periscope Techniques for Total Visceral and Renal Artery Revascularization

    Energy Technology Data Exchange (ETDEWEB)

    Cariati, Maurizio, E-mail: cariati.maurizio@sancarlo.mi.it [San Carlo Borromeo Hospital, Department of Diagnostic Sciences (Italy); Mingazzini, Pietro; Dallatana, Raffaello [San Carlo Borromeo Hospital, Department of Vascular Surgery (Italy); Rossi, Umberto G. [San Carlo Borromeo Hospital, Department of Diagnostic Sciences (Italy); Settembrini, Alberto [San Carlo Borromeo Hospital, Università degli Studi di Milano (Italy); Santuari, Davide [San Carlo Borromeo Hospital, Department of Vascular Surgery (Italy)

    2013-05-02

    Conventional endovascular therapy of thoracoabdominal aortic aneurysm with involving visceral and renal arteries is limited by the absence of a landing zone for the aortic endograft. Solutions have been proposed to overcome the problem of no landing zone; however, most of them are not feasible in urgent and high-risk patients. We describe a case that was successfully treated by total endovascular technique with a two-by-two chimney-and-periscope approach in a patient with acute symptomatic type IV thoracoabdominal aortic aneurysm with supra-anastomotic aneurysm formation involving the renal and visceral arteries and a pseduaneurismatic sac localized in the left ileopsoas muscle.

  5. Acetoanaerobium pronyense sp. nov., an anaerobic alkaliphilic bacterium isolated from a carbonate chimney of the Prony Hydrothermal Field (New Caledonia)

    OpenAIRE

    Bes, M. (Marta); Merrouch, M.; Joseph, Manon; Quéméneur, Marianne; Payri, Claude; Pelletier, Bernard; Ollivier, Bernard; Fardeau, Marie-Laure; Erausol, G.; A. Postec

    2015-01-01

    A novel anaerobic bacterial strain, ST07-YET, was isolated from a carbonate chimney of the Prony Hydrothermal Field (PHF) in New Caledonia. Cells were Gram-stain-positive, straight rods (0.7-0.8 x 3.0-5.0 mu m) and motile by means of lateral flagella. Strain ST07-YET was mesophilic (optimum 35 degrees C), moderately alkaliphilic and halotolerant (optimum pH 8.7 and 5 gr l(-1) NaCl). Elemental sulfur, sulfate, thiosulfate, sulfite, nitrate and nitrite were not used as terminal electron accepto...

  6. Validation experiments of the chimney model for the operational simulation of hydrogen recombiners; Experimente zur Validierung eines Kaminmodells fuer die Simulation des Betriebsverhaltens eines Wasserstoffrekombinators

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Berno [RWTH Aachen Univ. (Germany). Lehrstuhl fuer Reaktorsicherheit und -technik (LRST)

    2013-07-01

    The calculation program REKO-DIREKT allows the simulation of the operational behavior of a hydrogen recombiner during accidents with hydrogen release. The interest is focused on the interaction between the catalyst insertion and the chimney that influences the natural ventilation and thus the throughput through the recombiner significantly. For validation experiments were performed with a small-scale recombiner model in the test facility REKO-4. The results show the correlation between the hydrogen concentration at the recombiner entrance, the temperature on catalyst sheets and the entrance velocity using different chimney heights. The entrance velocity increases with the heights of the installed chimney that influences the natural ventilation significantly. The results allow the generation of a wide data base for validation of the computer code REKO-DIREKT.

  7. Impact of the Colonization by Paralvinella sulfincola on the Microbial Diversity Associated with a Deep-Sea Hydrothermal Vent Sulfide Chimney (Axial Seamount, Juan de Fuca Ridge)

    Science.gov (United States)

    Page, A.; Juniper, K.; Olagnon, M.; Alain, K.; Desrosiers, G.; Querellou, J.; Cambon-Bonavita, M.

    2002-12-01

    In the early stages of high temperature deep-sea hydrothermal vent chimneys growth, the walls remain porous and allow the escape of hydrothermal fluids as well as an inflow of seawater. This gradual mixing creates sharp thermal and geochemical gradients and provides potential habitats for physiologically diverse microorganisms. The annelid polychaete Paralvinella sulfincola colonizes the external surfaces of these structures, covering them with layered mucous tubes that locally alter the mixing of discharged hydrothermal fluids and surrounding seawater. Modifications of the physical and chemical conditions combined with an accumulation of elemental sulfur (S0) in P. sulfincola mucous tube are thought to be responsible for the deposition of a thin marcassite (FeS2) crust on outer surfaces of anhydrite chimneys (Juniper et al. 1992). This marcassite deposition could partly be induced by a shift in the composition of microbial communities that would to be locally associated with the presence of P. sulfincola. To test this hypothesis, we evaluated the impact of the colonization by P. sulfincola on the microbial communities present at the surface of an active sulfide chimney. Bacterial and archaeal 16S rRNA genes were amplified from DNA extracted from a P. sulfincola tube and from a chimney mineral sample. Using the statistical analysis demonstrated by Singleton et al. (2001), both clone libraries from the chimney sample have been shown to be significantly different from those of the P. sulfincola tube sample, even though the major phylogenetic groups of these libraries were similar. As it has been observed at other deep-sea hydrothermal vent sites, the Epsilon-Proteobacteria and the Deep-sea Hydrothermal Vent Euryarchaeotic Group 1 were the dominant components of both bacterial and archaeal clone libraries. These results seem to indicate that P. sulfincola affect the microbial community composition on high temperature chimneys.

  8. Severe compression of a bailout self-expanding chimney stent for rescuing the miscoverage of left common carotid artery during TEVAR of a type B aortic dissection.

    Science.gov (United States)

    Wang, Lixin; Guo, Daqiao; Jiang, Junhao; Shi, Zhenyu; Fu, Weiguo; Wang, Yuqi

    2014-04-01

    A 54-year-old man who suffered from paraplegia due to type B aortic dissection was treated with a Valiant stent-graft. However, attempts to gain secure proximal sealing resulted in an inadvertent coverage of the left common carotid artery by the endograft. The blood flow in the left common carotid artery was restored by a transcarotid Smart Control stent in a chimney fashion. At 6- and 18-month follow-up, computed tomography scan showed that the chimney stent was severely compressed by the stent graft, although the patient remained neurologically asymptomatic. PMID:24309751

  9. High-resolution 3D seismic investigations of hydrate-bearing fluid-escape chimneys in the Nyegga region of the Voring Plateau, Norway

    Energy Technology Data Exchange (ETDEWEB)

    Westbrook, G.; Exley, R. [Birmingham Univ., Birmingham (United Kingdom). School of Geography, Earth and Environmental Sciences; Minshull, T.; Jose, T. [National Oceanography Centre, Southampton (United Kingdom); Nouze, H.; Ker, S. [French Research Inst. for Exploitation of the Sea (France). Dept. of Geosciences; Gailler, A. [Birmingham Univ., Birmingham (United Kingdom). School of Geography, Earth and Environmental Sciences]|[French Research Inst. for Exploitation of the Sea (France). Dept. of Geosciences; Plaza, A. [Tromso Univ., Tromso (Norway). Inst. for Geology]|[French Research Inst. for Exploitation of the Sea (France). Dept. of Geosciences

    2008-07-01

    Seismic surveys in the southeast part of the Voring plateau on the Norwegian continental shelf have revealed hundreds of pockmarks and mounds which appear to be the seabed terminations of chimney-like structures. The seismic characteristics are very similar to chimneys in the accretionary complex off Vancouver Island, Canada. The pockmarks are sites of methane seeps colonized by chemosynthetic biota. There is extensive development of authigenic carbonate within the pockmarks. There are many indicators that free gas exists beneath the base of the gas hydrate stability zone (GHSZ). The observed thinning of the time intervals between reflectors in the flanks of chimneys could be caused by the presence of higher velocity material such as hydrate or authigenic carbonate. Evidence for the presence of hydrate was obtained from cores at 5 locations during a seismic survey conducted in 2006. Two of these pockmarks, each about 300-m wide with active seeps within them, were the sites of high-resolution seismic experiments using Ocean-Bottom Seismic recorders with 100-m separation to investigate the 3-D variation in their structure and properties. Travel-time tomography was used to detail the variation in Vp and Vs within and around the chimneys. It was concluded that the material within the CNE03 chimney that gave a higher seismic velocity could be carbonate or hydrate. Coring of hydrate from this feature favours the presence of hydrate. It was suggested that on average, hydrate may occupy up to 35 per cent of the pore space. The bending of strata in the flanks is partly deformational in origin, implying that the chimney was created by some forceful process, and now acts as a pathway for methane-rich fluid flow. The strata in the flanks of the G11 pockmark do not bend upwards. The pockmarks are underlain by a zone of locally higher content of free gas, approximately 5 km across. The chimneys beneath the pockmarks penetrate this zone. Many other smaller chimney-like structures

  10. REE and Sr-Nd isotope characteristics of hydrothermal chimney at Jade area in the Okinawa Trough

    Institute of Scientific and Technical Information of China (English)

    LIU Yanguang; MENG Xianwei; FU Yunxia

    2004-01-01

    Hydrothermal chimney is a product of hydrothermal activity on the seabed. Chimney samples dredged from Jade hydrothermal area in Izena depression of the Okinawa Trough, are characterized by relatively enriched light rare earth elements (LREE) and strongly positive Eu anomalies. 87Sr/86Sr and 143Nd/144Nd of these samples are exactly between those of seawater and of acidic pumice, averaged at 0.708928 and 0.512292, respectively. These characteristics imply that the main source of hydrothermal sulfide at Jade area is possibly the undersurface acidic rocks. The mineralizing mechanism can be summarized as follows: Large amount of mineralized material would be leached out and LREEenriched hydrothermal solution would be subsequently produced as a result of thermo-chemical exchange reaction between acidic volcanic rocks and heated seawater that penetrated in advance from upper water mass. The spurting out from the seabed and quickly crystallizing in the seawater of hydrothermal solution are responsible for the formation of Cu-Zn sulfide and barite-amorphous SiO2 minerals that are characterized by enriched LREE and positively strong Eu anomalies.

  11. Microbial and Mineral Descriptions of the Interior Habitable Zones of Active Hydrothermal Chimneys from the Endeavour Segment, Juan de Fuca Ridge

    Science.gov (United States)

    Holden, J. F.; Lin, T.; Ver Eecke, H. C.; Breves, E.; Dyar, M. D.; Jamieson, J. W.; Hannington, M. D.; Butterfield, D. A.; Bishop, J. L.; Lane, M. D.

    2013-12-01

    Actively venting hydrothermal chimneys and their associated hydrothermal fluids were collected from the Endeavour Segment, Juan de Fuca Ridge to determine the mineralogy, chemistry and microbial community composition of their interiors. To characterize the mineralogy, Mössbauer, FTIR, VNIR and thermal emission spectroscopies were used for the first time on this type of sample in addition to thin-section petrography, x-ray diffraction and elemental analyses. A chimney from the Bastille edifice was Fe-sulfide rich and composed primarily of chalcopyrite, marcasite-sphalerite, and pyrrhotite while chimneys from the Dante and Hot Harold edifices were Fe-sulfide poor and composed primarily of anhydrite. The bulk emissivity and reflectance spectroscopies corroborated well with the petrography and XRD analyses. The microbial community in the interior of Bastille was most closely related to mesophilic-to-thermophilic anaerobes of the deltaproteobacteria and hyperthermophilic archaea while those in the interiors of Dante and Hot Harold were most closely related to mesophilic-to-thermophilic aerobes of the beta-, gamma- and epsilonproteobacteria. The fluid temperatures (282-321°C) and chemistries of the three chimneys were very similar suggesting that differences in mineralogy and microbial community compositions were more dependent on fluid flow characteristics and paragenesis within the chimney. Thin-section petrography of the interior of another hydrothermal chimney collected from the Dante edifice (emitting 336°C fluid) shows a thin coat of Fe3+ oxide associated with amorphous silica on the exposed outer surfaces of pyrrhotite, sphalerite and chalcopyrite in pore spaces, along with anhydrite precipitation in the pores that is indicative of seawater ingress. The Fe-sulfide minerals were likely oxidized to ferrihydrite with increasing pH and Eh due to cooling and seawater exposure, providing reactants for bioreduction. Culture-based most-probable-number estimates of

  12. The Guaymas Basin Hiking Guide to Hydrothermal Mounds, Chimneys, and Microbial Mats: Complex Seafloor Expressions of Subsurface Hydrothermal Circulation.

    Science.gov (United States)

    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.

  13. Chimney-Graft as a Bail-Out Procedure for Endovascular Treatment of an Inflammatory Juxtarenal Abdominal Aortic Aneurysm

    Directory of Open Access Journals (Sweden)

    Francesca Fratesi

    2015-01-01

    Full Text Available Inflammatory and juxtarenal Abdominal Aortic Aneurysm (j-iAAA represents a technical challenge for open repair (OR due to the peculiar anatomy, extensive perianeurysmal fibrosis, and dense adhesion to the surrounding tissues. A 68-year-old man with an 11 cm asymptomatic j-iAAA was successfully treated with elective EVAR and chimney-graft (ch-EVAR without postprocedural complications. Target vessel patency and normal renal function are present at 24-month follow-up. The treatment of j-iAAA can be technically challenging. ch-EVAR is a feasible and safe bail-out method for elective j-iAAA with challenging anatomy.

  14. 燃煤电厂脱硫烟囱防腐技术创新和应用探讨%Discussion on technology innovation of coal -fired power plant desulfurization chimney corrosion and its application

    Institute of Scientific and Technical Information of China (English)

    张庆虎; 吴金土

    2015-01-01

    Through the analysis of the existing coal-fired power plant desulfurization chimney corrosion technolo-gy, summed up the basic reason desulfurization chimney corrosion failures, technological innovation ideas pro-posed chimney desulfurization corrosion.And briefly describes the use of self-vulcanized butyl rubber anti-corrosion lining for coal-fired power plant desulfurization chimney antiseptic feasibility and success stories.%通过对现行燃煤电厂脱硫烟囱防腐技术分析,总结了脱硫烟囱防腐失效的原因,提出了脱硫烟囱防腐的技术创新思路。简要介绍了采用自硫化丁基橡胶防腐衬里对燃煤电厂脱硫烟囱进行防腐的可行性和成功案例。

  15. Composition of hydrothermal fluids and mineralogy of associated chimney material on the East Scotia Ridge back-arc spreading centre

    Science.gov (United States)

    James, Rachael H.; Green, Darryl R. H.; Stock, Michael J.; Alker, Belinda J.; Banerjee, Neil R.; Cole, Catherine; German, Christopher R.; Huvenne, Veerle A. I.; Powell, Alexandra M.; Connelly, Douglas P.

    2014-08-01

    The East Scotia Ridge is an active back-arc spreading centre located to the west of the South Sandwich island arc in the Southern Ocean. Initial exploration of the ridge by deep-tow surveys provided the first evidence for hydrothermal activity in a back-arc setting outside of the western Pacific, and we returned in 2010 with a remotely operated vehicle to precisely locate and sample hydrothermal sites along ridge segments E2 and E9. Here we report the chemical and isotopic composition of high- and low-temperature vent fluids, and the mineralogy of associated high-temperature chimney material, for two sites at E2 (Dog’s Head and Sepia), and four sites at E9 (Black & White, Ivory Tower, Pagoda and Launch Pad). The chemistry of the fluids is highly variable between the ridge segments. Fluid temperatures were ∼350 °C at all vent sites except Black & White, which was significantly hotter (383 °C). End-member chloride concentrations in E2 fluids (532-536 mM) were close to background seawater (540 mM), whereas Cl in E9 fluids was much lower (98-220 mM) indicating that these fluids are affected by phase separation. Concentrations of the alkali elements (Na, Li, K and Cs) and the alkaline earth elements (Ca, Sr and Ba) co-vary with Cl, due to charge balance constraints. Similarly, concentrations of Mn and Zn are highest in the high Cl fluids but, by contrast, Fe/Cl ratios are higher in E9 fluids (3.8-8.1 × 10-3) than they are in E2 fluids (1.5-2.4 × 10-3) and fluids with lowest Cl have highest Cu. Although both ridge segments are magmatically inflated, there is no compelling evidence for input of magmatic gases to the vent fluids. Fluid δD values range from 0.2‰ to 1.5‰, pH values (3.02-3.42) are not especially low, and F concentrations (34.6-54.4 μM) are lower than bottom seawater (62.8 μM). The uppermost sections of conjugate chimney material from E2, and from Ivory Tower and Pagoda at E9, typically exhibit inner zones of massive chalcopyrite enclosed

  16. Growth of gas hydrate mounds and gas chimneys of the eastern margin of Japan Sea as revealed by MBES, SSS and SBP of AUV

    Science.gov (United States)

    Matsumoto, R.; Satoh, M.; Hiromatsu, M.; Tomaru, H.; Machiyama, H.

    2010-12-01

    A series of PC, ROV and SCS surveys to study the origin and evolution of gas hydrate systems along the eastern margin of Japan Sea have identified a number of shallow GH accumulations on the mounds, 300m to 500m in diameter and 30m to 40m high, on the Umitaka spur and Joetsu knoll in Joetsu basin with the WD of 880m to 1200m (Matsumoto et al., 2005; 2009). All of the hydrate mounds develop on gas chimneys as recognized by seismic profiles, and some are associated with gigantic methane plumes, 600m to 700m high. Multi Beam Echo Sounder (MBES), Side Scan Sonar (SSS) and Sub-Bottom Profiler (SBP) of AUV Urashima have revealed ultra-high resolution topographic features and subsurface structures of the mounds and adjacent areas during the JAMSTEC YK10-08 cruise, July 2010. AUV Urashima ran over the spur and knoll at 50m to 80m above seafloor at a cruising speed of 2.4 knots. MBES and SSS mosaics demonstrate two types of mounds. One is a low swell with smooth surface and weak reflectance, while the other is characterized by rough and uneven topographic features with strong SSS images due to incrustation by methane-induced carbonate concretions and gas hydrates. SBP provides clear stratigraphic and structural relations down to 50mbsf to 80mbsf and recognizes three stratigraphic units as I: upper massive unit (5-10m thick), II: middle evenly bedded unit (15-25m thick) and III: lower slightly bedded unit (> 15-25m thick). Gas chimneys grow up toward the seafloor through Units III, II, and I. When the ceiling of gas chimney stays within Unit III or II, the mound above the chimney is either low swell or nearly flat, while the swell grows up higher when the ceiling reaches to Unit I or the seafloor. Eventually, the ceiling breaks through the seafloor and protrudes to form GH mound up to 40m to 50m high, and then start to decay probably due to mechanical collapse and chemical dissolution of gas hydrates. The ceiling of gas chimneys is often represented by high amplitude, uneven

  17. Metagenome and Metatranscriptome Revealed a Highly Active and Intensive Sulfur Cycle in an Oil-Immersed Hydrothermal Chimney in Guaymas Basin.

    Science.gov (United States)

    He, Ying; Feng, Xiaoyuan; Fang, Jing; Zhang, Yu; Xiao, Xiang

    2015-01-01

    The hydrothermal vent system is a typical chemosynthetic ecosystem in which microorganisms play essential roles in the geobiochemical cycling. Although it has been well-recognized that the inorganic sulfur compounds are abundant and actively converted through chemosynthetic pathways, the sulfur budget in a hydrothermal vent is poorly characterized due to the complexity of microbial sulfur cycling resulting from the numerous parties involved in the processes. In this study, we performed an integrated metagenomic and metatranscriptomic analysis on a chimney sample from Guaymas Basin to achieve a comprehensive study of each sulfur metabolic pathway and its hosting microorganisms and constructed the microbial sulfur cycle that occurs in the site. Our results clearly illustrated the stratified sulfur oxidation and sulfate reduction at the chimney wall. Besides, sulfur metabolizing is closely interacting with carbon cycles, especially the hydrocarbon degradation process in Guaymas Basin. This work supports that the internal sulfur cycling is intensive and the net sulfur budget is low in the hydrothermal ecosystem.

  18. Use of Oriented Spray Nozzles to Set the Vapor-Air Flow in Rotary Motion in the Superspray Space of the Evaporative Chimney-Type Tower

    Science.gov (United States)

    Dobrego, K. V.; Davydenko, V. F.; Koznacheev, I. A.

    2016-01-01

    The present paper considers the problem of upgrading the thermal efficiency of chimney-type evaporative cooling towers due to the rotary motion of the vapor-air flow in the superspray space. To set the vapor-air flow in rotary motion, we propose to use the momentum of the sprayed water. It has been shown that the existing parameters of spray nozzles permit setting up to 30% of the water flow momentum in translatory motion, which is enough for changing considerably the aerodynamics of the vapor-air flow in the superspray space and improving the operation of the cooling tower. The optimal angle of axial inclination of the spray cone has been estimated. Recommendations are given and problems have been posed for engineering realization of the proposed technologies in a chimney-type cooling tower.

  19. Experimental Study Using the Passive Solar Chimney for Evaporative Cooling With PCM and CFM as a Thermal Energy Storage

    Directory of Open Access Journals (Sweden)

    Talib K. Murtadha

    2016-09-01

    Full Text Available In this work, a test room was built in Baghdad city, with (2*1.5*1.5 m3 in dimensions, while the solar chimneys (SC were designed with aspect ratio (ar bigger than 12. Test room was supplied by many solar collectors; vertical single side of air pass with ar equals 25, and tilted 45o double side of air passes with ar equals 50 for each pass, both collectors consist of flat thermal energy storage box collector (TESB that covered by transparent clear acrylic sheet, third type of collector is array of evacuated tubular collectors with thermosyphon in 45o instelled in the bottom of TESB of vertical SC. The TESB was made from metallic iron sheets as a shell and fuelled by paraffin wax as phase change material (PCM. The PCM supported by copper foam matrix (CFM to enhance thermal conductivity of wax. When heat is released from TESB to the air, a buoyancy force will be generated in chimney gaps. Then a difference in pressure between inside and outside test room leads to induce the air flow to test room through wet corrugated cellulose pad, where evaporative cooling (EC occurs. Results of experimental work, that achieved in June, for 12 to24 hour in the test day, refer to effectiveness using EC to decrease the room temperature comparing. The system reduces test room temperature of up to 8.5~9.2 oC in 11:00 am to 3:00 pm and at highest effectiveness of EC, while minimum reduces in temperature of up to 3.5 oC in 8:00pm to 3:00 am. Also, the results showed the affectivity to using the TESB, during the night time for ventilation and EC, with lower effectiveness than from day time. The range of EC effectiveness equals 30.5-37.5 with a natural vent, while The maximum air change per hour (ACH equals (3.8-6.187, and the maximum mass flow rate is equal to (36.651 kg.hr-1 at experimental evaluation of the system’s discharge coefficient value 0.371.

  20. Fermentative hydrogen production by a new alkaliphilic Clostridium sp (strain PROH2) isolated from a shallow submarine hydrothermal chimney in Prony Bay, New Caledonia

    OpenAIRE

    MEI, N.; Zergane, N.; Postec, A.; Erauso, G.; Oilier, A.; Payri, Claude; Pelletier, Bernard; Fardeau, Marie-Laure; Ollivier, Bernard; Quéméneur, Marianne

    2014-01-01

    The hydrogen-producing strain PROH2 pertaining to the genus Clostridium was successfully isolated from a shallow submarine hydrothermal chimney (Prony Bay, New Caledonia) driven by serpentinization processes. Cell biomass and hydrogen production performances during fermentation by strain PROH2 were studied in a series of batch experiments under various conditions of pH, temperature, NaCl and glucose concentrations. The highest hydrogen yield, 2.71 mol H-2/mol glucose, was observed at initial ...

  1. Personal child and mother carbon monoxide exposures and kitchen levels: Methods and results from a randomized trial of woodfired chimney cookstoves in Guatemala (RESPIRE)

    OpenAIRE

    Smith, Kirk R.; McCracken, John P; Thompson, Lisa; Edwards, Rufus; SHIELDS, KYRA N.; Canuz, Eduardo; Bruce, Nigel

    2009-01-01

    During the first randomized intervention trial (RESPIRE: Randomized Exposure Study of Pollution Indoors and Respiratory Effects) in air pollution epidemiology, we pioneered application of passive carbon monoxide (CO) diffusion tubes to measure long-term personal exposures to woodsmoke. Here we report on the protocols and validations of the method, trends in personal exposure for mothers and their young children, and the efficacy of the introduced improved chimney stove in reducing personal ex...

  2. Electricity production with low grade heat in thermal power plants by design improvement of a hybrid dry cooling tower and a solar chimney concept

    International Nuclear Information System (INIS)

    Highlights: • A system of a dry cooling tower and a solar chimney are recombined. • The hot flue gas is injected in the hybrid tower to maximize the power output. • Effects of the angle of the tower walls (convergent or divergent) are studied. • Effects of the collector roof slope and base ground slope are studied. • The thermal efficiency of a 250 MW power plant is increased more than 0.5%. - Abstract: In this study, an improved concept design is presented to increase the thermal efficiency of the Rankine cycle of a typical steam power plant by combining a solar chimney and a dry cooling tower. The sources of the wind energy generation, include: the rejected heat from condenser to the air entering dry cooling tower, solar radiation and the airlift pumping effect on the air flow created by the stack hot flue gas which is injected into the hybrid tower as a novel change. This research primarily focuses on the Shahid Rajaee 250 MW steam power plant to determine the velocity of generated flow at the turbine inlet; a numerical finite volume code was employed for a dry cooling tower having a base diameter and a chimney height of 250 and 200 m, respectively. Calculations have been iterated for different angles of chimney walls, slopes of collectors and the base ground to find their effects on the output power. A range of 360 kW to more than 4.4 MW power is captured by the wind turbine by changing the hybrid tower geometrical parameters. Obtained results reveal a maximum of 0.538% increase for the thermal efficiency of the fossil fuel power plant

  3. Abundances of Hyperthermophilic Autotrophic Fe(III) Oxide Reducers and Heterotrophs in Hydrothermal Sulfide Chimneys of the Northeastern Pacific Ocean ▿ †

    OpenAIRE

    Ver Eecke, Helene C.; Kelley, Deborah S.; Holden, James F.

    2008-01-01

    The abundances of hyperthermophilic heterotrophs, methanogens, and autotrophic reducers of amorphous Fe(III) oxide in 18 samples of deep-sea hydrothermal vent sulfide chimneys of the Endeavour Segment were measured. The results indicate that conditions favor the growth of iron reducers toward the interiors of these deposits and that of heterotrophs toward the outer surfaces near high-temperature polychaete worms (Paralvinella sulfincola).

  4. Complete Genome Sequence of the Hyperthermophilic Archaeon Pyrococcus sp. Strain ST04, Isolated from a Deep-Sea Hydrothermal Sulfide Chimney on the Juan de Fuca Ridge

    OpenAIRE

    Jung, Jong-Hyun; Lee, Ju-Hoon; Holden, James F.; Seo, Dong-Ho; Shin, Hakdong; Kim, Hae-Yeong; Kim, Wooki; Ryu, Sangryeol; Park, Cheon-Seok

    2012-01-01

    Pyrococcus sp. strain ST04 is a hyperthermophilic, anaerobic, and heterotrophic archaeon isolated from a deep-sea hydrothermal sulfide chimney on the Endeavour Segment of the Juan de Fuca Ridge in the northeastern Pacific Ocean. To further understand the distinct characteristics of this archaeon at the genome level (polysaccharide utilization at high temperature and ATP generation by a Na+ gradient), the genome of strain ST04 was completely sequenced and analyzed. Here, we present the complet...

  5. Abundances of Hyperthermophilic Autotrophic Fe(III) Oxide Reducers and Heterotrophs in Hydrothermal Sulfide Chimneys of the Northeastern Pacific Ocean ▿ †

    Science.gov (United States)

    Ver Eecke, Helene C.; Kelley, Deborah S.; Holden, James F.

    2009-01-01

    The abundances of hyperthermophilic heterotrophs, methanogens, and autotrophic reducers of amorphous Fe(III) oxide in 18 samples of deep-sea hydrothermal vent sulfide chimneys of the Endeavour Segment were measured. The results indicate that conditions favor the growth of iron reducers toward the interiors of these deposits and that of heterotrophs toward the outer surfaces near high-temperature polychaete worms (Paralvinella sulfincola). PMID:18978076

  6. Framework for the Energetic Assessment of South and South-East Asia Fixed Chimney Bull’s Trench Kiln

    Directory of Open Access Journals (Sweden)

    Brun Niccolò Le

    2016-01-01

    Full Text Available One of the major sources of fuel consumption and greenhouse gas emission in South and South-East Asia is brick manufacturing. One of the most commonly implemented technologies for brick manufacturing in this region is the fixed chimney Bull’s trench kiln (FCBTK. This type of technology largely depends on manual labour and is very inefficient when compared to more modern technologies. Because the adoption of more advanced technologies is hindered by the socio-economical background, the much needed innovations in the brick sector are necessarily related to improving/modifying the FCBTK already operational. However, few scientific studies have been conducted on FCBTK probably due to the basic level of technological development. Such studies are however important to systematically and methodologically assess the challenges and solutions in FCBTK. In this study we develop a thermo-energetic model to evaluate the importance of the parameters pertained to FCBTK construction and operation. The prospective of this study is to build an initial thermo-energetic framework that will serve as a basis to investigate possible energetic improvements.

  7. Acetoanaerobium pronyense sp. nov., an anaerobic alkaliphilic bacterium isolated from a carbonate chimney of the Prony Hydrothermal Field (New Caledonia).

    Science.gov (United States)

    Bes, Méline; Merrouch, Mériem; Joseph, Manon; Quéméneur, Marianne; Payri, Claude; Pelletier, Bernard; Ollivier, Bernard; Fardeau, Marie-Laure; Erauso, Gaël; Postec, Anne

    2015-08-01

    A novel anaerobic bacterial strain, ST07-YET, was isolated from a carbonate chimney of the Prony Hydrothermal Field (PHF) in New Caledonia. Cells were Gram-stain-positive, straight rods (0.7-0.8 × 3.0-5.0 μm) and motile by means of lateral flagella. Strain ST07-YET was mesophilic (optimum 35 °C), moderately alkaliphilic and halotolerant (optimum pH 8.7 and 5 g l- 1 NaCl). Elemental sulfur, sulfate, thiosulfate, sulfite, nitrate and nitrite were not used as terminal electron acceptors. Yeast extract, peptone, tryptone, Casamino acids, crotonate, pyruvate, galactose, maltose, sucrose, ribose, trehalose and glucose were used as carbon sources. Glucose fermentation led to acetate, H2 and CO2 formation. Arginine, serine, histidine, lysine, methionine and cysteine improved growth, but the Stickland reaction was negative for the combinations of amino acids tested. The major metabolic products from yeast extract fermentation were H2, CO2, acetate, butyrate, isobutyrate, isovalerate and propionate. The predominant cellular fatty acids were C16  :  0, C16  :  1cis9, C14  :  0 and C16  :  1cis7 (>5 % of total fatty acids). The G+C content of the genomic DNA was 32.9 mol%. Phylogenetic analysis revealed that strain ST07-YET was most closely related to Clostridium sticklandii DSM 519T and Acetoanaerobium noterae NOT-3T (96.7 % and 96.8 % 16S rRNA gene sequence similarity, respectively). On the basis of phylogenetic, chemotaxonomic and physiological properties, strain ST07-YET is proposed to represent a novel species of the genus Acetoanaerobium (order Clostridiales, phylum Firmicutes) with the name Acetoanaerobium pronyense sp. nov. The type strain is ST07-YET ( = DSM 27512T = JCM 19400T). PMID:25948619

  8. Geologic, geophysical, and in-situ stress investigations in the vicinity of the Dining Car chimney, Dining Car/Hybla Gold Drifts, Nevada Test Site

    International Nuclear Information System (INIS)

    The Hybla Gold event, detonated on Nov. 1, 1977, was conducted in the U12e.20 drifts of the E-tunnel complex beneath the surface of Rainier Mesa at the Nevada Test Site. Though the proximity of the Hybla Gold working point to the chimney of the Dining Car event was important to the experiment, the observable geologic effects from Dining Car on the Hybla Gold site were minor. Overburden above the working point is approximately 385 m (1263 ft). The pre-Tertiary surface, probably quartzite, lies approximately 254 m (833 ft) below the working point. This report comprises three chapters detailing the geologic, geophysical, and in situ stress data gathered in the period January through June 1977, in the course of mining and drilling in the Hybla Gold/Dining Car region. These investigations confirm several observations reported previously for the Rainier event, i.e., a zone of microfailure observable in thin-section and in physical properties exists adjacent to the chimney. In addition, however, a number of investigations add new information to our understanding of effects near the detonation point. Shear waves were found to be highly diagnostic in the microcracked zone near the chimney as well as zones of failure at greater range not discernible as well as zones of failure at greater range not discernible by other techniques. Extensive in situ stress measurements made by the hydrofracture and overcore techniques indicate changes in the orientation and magnitude of the pre-Dining Car stress field. The hydrofracture technique further suggests pronounced gradients in minimum stress magnitudes over short distances at some locations in the postshot stress regime

  9. Characterization of Alkaliphilus hydrothermalis sp nov., a novel alkaliphilic anaerobic bacterium, isolated from a carbonaceous chimney of the Prony hydrothermal field, New Caledonia

    OpenAIRE

    Ben Aissa, F.; Postec, A.; Erauso, G.; Payri, Claude; Pelletier, Bernard; Hamdi, M.; Fardeau, Marie-Laure; Ollivier, Bernard

    2015-01-01

    A novel anaerobic, alkaliphilic, Gram-positive staining bacterium was isolated from a hydrothermal chimney in the Prony Bay, New Caledonia. This strain designated FatMR1(T) grew at temperatures from 20 to 55 A degrees C (optimum 37 A degrees C) and at pH between 7.5 and 10.5 (optimum 8.8-9). NaCl is not required for growth (optimum 0.2-0.5 %), but is tolerated up to 3 %. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite are not used as terminal electron acceptors. Strain Fa...

  10. Novel barite chimneys at the Loki´s Castle Vent Field shed light on key factors shaping microbial communities and functions in hydrothermal systems

    Directory of Open Access Journals (Sweden)

    Ida Helene eSteen

    2016-01-01

    Full Text Available In order to fully understand the cycling of elements in hydrothermal systems it is critical to understand intra-field variations in geochemical and microbiological processes in both focused, high-temperature and diffuse, low-temperature areas. To reveal important causes and effects of this variation, we performed an extensive chemical and microbiological characterization of a low-temperature venting area in the Loki’s Castle Vent Field (LCVF. This area, located at the flank of the large sulfide mound, is characterized by numerous chimney-like barite (BaSO4 structures (≤ 1m high covered with white cotton-like microbial mats. Results from geochemical analyses, microscopy (FISH, SEM, 16S rRNA gene amplicon-sequencing and metatranscriptomics were compared to results from previous analyses of biofilms growing on black smoker chimneys at LCVF. Based on our results, we constructed a conceptual model involving the geochemistry and microbiology in the LCVF. The model suggests that CH4 and H2S are important electron donors for microorganisms in both high-temperature and low-temperature areas, whereas the utilization of H2 seems restricted to high-temperature areas. This further implies that sub-seafloor processes can affect energy-landscapes, elemental cycling, and the metabolic activity of primary producers on the seafloor. In the cotton-like microbial mats on top of the active barite chimneys, a unique network of single cells of Epsilonproteobacteria interconnected by threads of extracellular polymeric substances (EPS was seen, differing significantly from the long filamentous Sulfurovum filaments observed in biofilms on the black smokers. This network also induced nucleation of barite crystals and is suggested to play an essential role in the formation of the microbial mats and the chimneys. Furthermore, it illustrates variations in how different genera of Epsilonproteobacteria colonize and position cells in different vent fluid mixing zones within

  11. Novel Barite Chimneys at the Loki's Castle Vent Field Shed Light on Key Factors Shaping Microbial Communities and Functions in Hydrothermal Systems.

    Science.gov (United States)

    Steen, Ida H; Dahle, Håkon; Stokke, Runar; Roalkvam, Irene; Daae, Frida-Lise; Rapp, Hans Tore; Pedersen, Rolf B; Thorseth, Ingunn H

    2015-01-01

    In order to fully understand the cycling of elements in hydrothermal systems it is critical to understand intra-field variations in geochemical and microbiological processes in both focused, high-temperature and diffuse, low-temperature areas. To reveal important causes and effects of this variation, we performed an extensive chemical and microbiological characterization of a low-temperature venting area in the Loki's Castle Vent Field (LCVF). This area, located at the flank of the large sulfide mound, is characterized by numerous chimney-like barite (BaSO4) structures (≤ 1 m high) covered with white cotton-like microbial mats. Results from geochemical analyses, microscopy (FISH, SEM), 16S rRNA gene amplicon-sequencing and metatranscriptomics were compared to results from previous analyses of biofilms growing on black smoker chimneys at LCVF. Based on our results, we constructed a conceptual model involving the geochemistry and microbiology in the LCVF. The model suggests that CH4 and H2S are important electron donors for microorganisms in both high-temperature and low-temperature areas, whereas the utilization of H2 seems restricted to high-temperature areas. This further implies that sub-seafloor processes can affect energy-landscapes, elemental cycling, and the metabolic activity of primary producers on the seafloor. In the cotton-like microbial mats on top of the active barite chimneys, a unique network of single cells of Epsilonproteobacteria interconnected by threads of extracellular polymeric substances (EPS) was seen, differing significantly from the long filamentous Sulfurovum filaments observed in biofilms on the black smokers. This network also induced nucleation of barite crystals and is suggested to play an essential role in the formation of the microbial mats and the chimneys. Furthermore, it illustrates variations in how different genera of Epsilonproteobacteria colonize and position cells in different vent fluid mixing zones within a vent field

  12. Additional income with open chimneys and stove. Nostalgia, romanticism and thermal comfort; Zusatzgeschaeft mit Oefen und Kaminen. Nostalgisch-romantische Gefuehle und behagliche Waerme

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, G. [Buderus Heiztechnik GmbH, Wetzlar (Germany)

    2004-01-01

    Stoves and open fireplaces are coming into fashion again with the trend towards nostalgia and design awareness. Further, wood-fuelled chimneys and stoves are viewed as romantic, and they also provide high thermal comfort. Heating systems experts can get additional income from this trend. (orig.) [German] Kamine und Oefen sind bei vielen Hausbesitzern und Bauherrn wieder in Mode. Dieser Trend ist zum einen Teil eines gestiegenen Nostalgie- und Designbewusstseins. Zum anderen gelten vor allem holzbefeuerte Kamine und Oefen als romantisch und ihre Waerme aufgrund des hohen Strahlungsanteils als behaglich. Fuer den aktiven Heizungsfachhandwerker laesst sich aus dieser Modestroemung ein lukratives Zusatzgeschaeft ableiten. (orig.)

  13. Hybrid Solar Chimney and Evaporative Cooling System Used in Xinjiang%新疆地区太阳能烟囱复合蒸发冷却通风降温系统

    Institute of Scientific and Technical Information of China (English)

    宣永梅; 马柱柱; 黄翔

    2013-01-01

    提出了太阳能烟囱复合蒸发冷却系统,对复合系统模型进行了理论分析及计算,得出通风量与烟囱高度、宽度及太阳辐射强度之间的关系。结果表明,太阳能烟囱的自然通风量随太阳能辐射强度及烟囱高度的增加而增加;在计算条件下,当宽度取1m 时通风量取得最大值。在此基础上分析得到太阳辐射照度400W/m2、烟囱高度3m、宽度1m 时,太阳能烟囱复合蒸发冷却系统应用于乌鲁木齐建筑时烟囱的理论通风量为0.21kg/s,该通风量基本满足乌鲁木齐夏季通风设计工况下,蒸发冷却降温时所需动力(0.23kg/s),且室内通风换气次数达到10次/h 以上,是一种节能环保的自然通风降温技术。%A hybrid system of solar chimney and evaporative cooling was proposed.The model of this hybrid system was studied by theoritical analysis and calculation.The relationships between air flow rate with chimney height,width and solar radiation were obtained.The calculation results indicated that the air flow rate of solar chimney increases with solar radiation and chimney height.Under design conditions,the air flow rate of solar chimney reaches its maximum value at solar chimney width of 1m. When applied to actual buildings in Urumqi,the obtained air mass flow rate (0.21kg/s)of solar chimney under optimum condi-tions (at chimney height of 3m,width of 1m,solar radiation of 400W/m2 )can approximately meet the ventilation requirements of evaporative cooling (0.23kg/s),and air changes more than 10 times per hour.The proposed hybrid system is an environmental friendly and energy efficient natural ventilation and free cooling technology.

  14. Treating patients with abdominal aortic aneurysm with endovascular repair and the crossover chimney technique in the internal iliac artery to protect the unilateral internal iliac artery

    Science.gov (United States)

    Guo, Xi; Li, Peng; Liu, Guang-Rui; Huang, Xiao-Yong; Huang, Lian-Jun

    2015-01-01

    This study aims to explore the treatment methods for patients with abdominal aortic aneurysms (AAAs) that required occlusion of the openings of the bilateral internal iliac arteries (IIAs) in endovascular aneurysm repair (EVAR) and to evaluate the efficacy of these treatments. Four patients with AAA were treated with endovascular aneurysm repair (EVAR) and the crossover chimney technique in the bilateral internal iliac arteries (IIAs). We inserted and released the abdominal aortic stent as usual and implanted the bypass stent graft simultaneously. The intraoperative immediate angiography showed complete isolation of the AAA and patency of the bypass. One month after surgery, it showed contrast engorgement in the bypass stent in three patients. The IIA on the bypass side and its branches had good developing. Another case in which we utilized a COOK stent, occlusion started at the opening of the bypass stent, with no occurrence of other complications. For patients in whom AAAs involve bilateral iliac arteries and the openings of the bilateral IIAs need to be occluded, EVAR and a crossover chimney technique can protect the unilateral IIA. PMID:26885136

  15. Enhanced bilateral somatostatin receptor expression in mediastinal lymph nodes (''chimney sign'') in occult metastatic medullary thyroid cancer: a typical site of tumour manifestation?

    International Nuclear Information System (INIS)

    In medullary thyroid cancer (MTC), post-surgically elevated plasma calcitonin and/or carcinoembryonic antigen levels frequently indicate persisting metastatic disease, although conventional diagnostic procedures fail to localize the responsible lesions (occult disease). Somatostatin analogues have been used successfully in disease localization, but recently concerns have been raised that increased thoracic uptake of indium-111 pentetreotide in patients with previous external beam irradiation may represent a false-positive finding, caused by post-irradiation pulmonary fibrosis. We recently examined seven patients with metastatic MTC by somatostatin receptor scintigraphy (six with occult and one with established disease). In four patients, all of whom had stable or slowly rising tumour marker levels over several years, a chimney-like bilateral mediastinal uptake of indium-111 pentetreotide was found. In two patients with persisting hypercalcitonaemia immediately after primary surgery, supraclavicular lymph node metastases were identified as the responsible lesions. None of these seven patients had prior external beam radiation therapy. In two cases, histological confirmation was obtained. In one patient, disease progression could be shown during follow-up. These data suggest that bilateral mediastinal lymph node involvement is a typical site of disease in slowly progressing occult metastatic MTC; the ''chimney sign'' may represent a typical finding with somatostatin analogues in such cases. Therefore, we believe that even in the case of prior external beam irradiation, mediastinal uptake of octreotide might represent metastatic MTC rather than radiation fibrosis. (orig.). With 2 figs., 1 tab

  16. Research on Design Technique of FRP-liners of Wet Chimney%湿烟囱玻璃钢内简结构设计技术研究

    Institute of Scientific and Technical Information of China (English)

    杨小兵; 田树桐; 阮明山; 马申

    2011-01-01

    The wet chimney with high-performance FRP( Fiberglass Reinforced Plastic) liners is effective scheme to solve the corrosion problem, however, the design technique need to be improved by virtue of less study and practice.In this paper, through analysis and calculation, such topics as failure mode of FRP material, safety factors and supporting style of liners was studied exhaustively on base of the service conditions of wet chimney and the design standards home and abroad. Then reasonable suggestions were pointed out. It can be referred for engineers in design and construction .%采用高性能玻璃钢内筒是解决环保燃煤电厂湿烟囱腐蚀问题的有效途径,但目前国内对玻璃钢烟囱结构设计研究较少,有关技术问题亟待解决.文章基于国内外玻璃钢结构设计规范和湿烟囱的使用条件,通过分析计算,对玻璃钢烟囱结构设计中材料失效模式、安全系数取值、内筒支承方式等技术问题进行了深入探讨,提出了合理的建议,可供有关工程技术人员参考.

  17. Analysis on the optimization geometry of the solar chimney power plant systems%太阳能热气流发电流道优化分析

    Institute of Scientific and Technical Information of China (English)

    职更辰; 陈威

    2013-01-01

    以西班牙太阳能热气流电站为原型进行数值模拟,得出了太阳能烟囱内的速度场、压力场和温度场分布;研究了集热棚坡度、分流板高度和弧度等因素对系统发电性能及涡轮机位置的影响.研究结果表明:集热棚坡度增加时,烟囱的抽吸作用增强,空气流速增加,有利于提高太阳能热气流发电的输出功率;当集热棚坡度约为0.5°时,其作用最为明显,对于提高系统发电性能最为有利;增加分流板有利于气流发电站的优化,当分流板高度略微高于集热棚高度时,优化效果较好;分流板弧度越小,越有利于系统的优化;集热棚坡度对涡轮机位置有影响,改变分流板的几何因素对涡轮机位置没有影响.%An Spanish solar chimney power plant was considered as a prototype to establish a numerical simulation in this paper, and the distribution of velocity, pressure and temperature fields in the solar chimney were derived; Thereby the impact of changing of geometric factors, which included the slope of the collector shed, the height and radians of the shunt board and so on, on the system power performance and the location of turbine were studied. Research results showed that, as the slope of the collector shed beginning to increase, the drawing action of the chimney increased and the velocity of air enhanced, which would help to improve the generator output of solar chimney; When the collector shed gradient increased to about 0.5 degrees, the strengthening of chimney drawing was the most obvious, which was the most advantageous for improving the system's power generation performance; The airflow power station performed better while increasing the number of manifold; When the manifold height was slightly higher than that of the collector shed, the system performed well; The slighter the curvature of manifold, the better the system presented. The slope of the collector shed affects location of the turbine, but the turbine

  18. 太阳能烟囱强化自然通风的研究现状%Research Status on Solar Chimney for Natural Ventilation Enhancement

    Institute of Scientific and Technical Information of China (English)

    苏亚欣; 柳仲宝

    2011-01-01

    Natural ventilation is an energy efficient passive cooling technology and it uses wind or thermal buoyancy to deliver fresh air into the buildings in order to maintain a good indoor air quality. Comparing with mechanical ventilation, natural ventilation has obvious energy-saving advantages. Solar Chimney (SC) is a vertical or inclined channel that utilizes solar radiation to cause a temperature rise and density drop for the air flowing through the chimney, therefore enhances the natural ventilation. First, two types of typical solar chimney, namely, Trombe wall-type and inclined roof-type solar chimney, and their basic principle to enhance natural ventilation are briefly introduced. Then, the parameters that influence the performance of natural ventilation of the solar chimney are discussed in detail. The major methods and result are listed based on the review of the research works on solar chimney by different authors. The height and depth (the distance between the glass cover and absorber wall) of SC influence the natural convection flow process and the temperature rise of air in the SC channel and furthermore influence the ventilation rate of the SC strongly. The ventilation air I.e. The air flow rate increases with the increase of SC depth. The air flow rate decreases when the SC depth exceeds an optimal value. A reverse flow appears near the top of the SC channel when the ratio of SC depth to height is larger than 2.5 and the increase of natural ventilation rate is limited. The effect of the SC structure and its inclined angle on ventilation is related to the geographical location and climate conditions. The modeling of SC ventilation includes the mathematical modeling that is based on the energy conservation analysis on the heat transfer process of the air on the wall surfaces and the numerical simulation of the flow process that is based on Computational Fluid Dynamics (CFD) method. Based on the literature review, the issues that need to be improved in solar

  19. In situ ore formation experiment: Amino acids and amino sugars trapped in artificial chimneys on deep-sea hydrothermal systems at Suiyo Seamount, Izu-Bonin Arc, Pacific Ocean

    CERN Document Server

    Takano,; Marumo,; K.,; Ebashi,; T.,; Gupta,; P., L; Kawahata,; H.,; Kobayashi,; K.,; Yamagishi,; A.,; Kuwabara,; T,

    2013-01-01

    The present study reports on the bio-organic composition of a deep-sea venting hydrothermal system originating from arc volcanism; the origin of the particulates in hydrothermal fluids from the Suiyo Seamount in the southern Izu-Bonin (Ogasawara) Arc is discussed with regard to amino compounds. Chimney samples on deep-sea hydrothermal systems and core samples at Suiyo Seamount were determined for amino acids, and occasionally amino sugars. Two types of chimney samples were obtained from active hydrothermal systems by submersible vehicles: one was natural chimney (NC) on a hydrothermal natural vent; the other was artificial chimneys (AC), mainly formed by the growth and deposition of sulfide-rich particulate components in a Kuwabara-type in situ incubator (KI incubator). Total hydrolyzed amino acids (THAA) and hydrolyzed hexosamines (HA) in AC ranged from 10.7 nmol/g to 64.0 nmol/g and from 0 nmol/g to 8.1 nmol/g, respectively, while THAA in hydrothermally altered core samples ranged from 26.0 nmol/g to 107.4 ...

  20. A Case of Successful Coil Embolization for a Late-Onset Type Ia Endoleak after Endovascular Aneurysm Repair with the Chimney Technique

    Directory of Open Access Journals (Sweden)

    Kimihiro Igari

    2016-01-01

    Full Text Available Juxtarenal aortic aneurysms (JRAAs are challenging to treat by endovascular aneurysm repair (EVAR procedures. The chimney technique with EVAR (Ch-EVAR is one of the feasible and less invasive treatments for JRAAs. However, the main concern of Ch-EVAR is the potential risk of “gutters,” which can lead to type Ia endoleak (EL. Most type Ia ELs after Ch-EVAR procedures occurred intraoperatively, and these ELs could be treated using an endovascular technique. However, late-onset type Ia ELs could be extremely rare, which might have a fear of conservative treatment. Type Ia ELs are associated with an increased risk of aneurysm rupture; therefore reintervention is recommended as soon as possible, and we should be aware of the occurrence of type Ia ELs after the Ch-EVAR procedure.

  1. 焦炉烟囱 NO x排放控制刍议%Comment on control of NOx emission from chimney of coke oven battery

    Institute of Scientific and Technical Information of China (English)

    蔡承祐

    2013-01-01

    The new national standard“ Emission standard of pollutants for coking chemical industry”regulates the requirement for control of NO x emission from chimney of coke oven battery .The techni-cal measures on design of heating system of coke oven battery and treatment of oven flue gas after it is discharged from the battery for control of NO x emission are expounded in this paper .The author also makes brief description of technology on denitrification of flue gas by using SCR process and sug -gests that in order to meet the requirement of the national standard for control of NO x emission from chimney of coke oven battery located in the “special region”, flue gas discharged from the coke oven battery should be further treated by using SCR denitrification technology with learning experience of Tokyo Gas gained from test of pilot plant and engineering .%新的国家标准《炼焦化学工业污染物排放标准》提出了焦炉烟囱的NOx 排放控制要求。本文从焦炉加热系统的设计和对焦炉烟道废气的后处理2个层面论述了焦炉烟囱NOx 排放控制的技术措施,简要介绍了SCR烟气脱硝技术,提出了借鉴日本东京煤气公司的中试与工程经验,采用SCR脱硝技术对焦炉烟道废气进行后处理,以达到国家标准对“特别地区”焦炉烟囱的NOx排放控制要求。

  2. Influence of wind effects on collapsing process of a chimney in blasting%爆破拆除烟囱倒塌过程中风效应影响研究

    Institute of Scientific and Technical Information of China (English)

    张宪堂; 王兆东; 王洪立; 王来

    2013-01-01

    在烟囱爆破拆除倒塌过程中,不同形式的风可使烟囱产生顺风向效应及横风向效应.横风向效应又包括横风向旋涡脱落及共振效应、横风向空气动力失稳.烟囱在风的长期作用下会发生失稳倾斜.揭示了爆破拆除过程中烟囱由于风振影响而发生倾斜、失稳的机理,分析了不同风向的三类风效应对爆破拆除时烟囱倒塌方向发生偏移的影响.根据分析计算结果可得,纵向风振影响最为显著,静力风效应影响相对较小,横向风振产生影响随机性较强.同时作者得出了爆破拆除烟囱时考虑风效应影响需采取的相应技术手段和措施.%In blasting demolition process of a chimney,along wind effect and across wind one are produced on the chimney under wind loads.The effect of across wind includes horizontal wind direction swirl,resonance effect and air dynamic destabilizing in horizontal wind direction.The long time action of wind load on a chimney during blasting demolition leads to sloping and destabilizing.The mechanism of sloping and destabilizing of a chimney due to windinduced vibration in its blasting demolition process was presented,and the deviations of the chimney collapsing direction during blasting demolition as results of three kinds of wind effect in different directions were analyzed.It was shown from the calculation results that the influence of along wind resonance is significant,the static wind effect is relatively small,and the influence of across wind resonance has a little stronger randomness.Also,the relevant technological measures needed considering the effect of wind in blasting demolition process of a chimney were obtained.

  3. 52m高裂缝砖烟囱小切口定向爆破拆除%DEMOLITION OF A 52 METERS HIGH BRICK CHIMNEY WITH CRACKS BY SMALL CUT DIRECTIONAL BLASTING

    Institute of Scientific and Technical Information of China (English)

    赵利坤; 曹跃; 褚夫蛟; 李晓虎

    2012-01-01

    介绍了52m高有裂缝砖烟囱的爆破拆除.在烟囱筒身存在长度达10m的裂缝、无法开定向窗的条件下,重点阐述了此烟囱爆破拆除的施工技术和方案设计.爆破中采用切口取小值、增大炸药单耗及一次性起爆的倒塌方案,精心设计了合理的爆破切口及爆破参数,并采取有效的防护措施,确保了烟囱按设计的方向倾倒.%Demolition blasting of a 52m high brick chimney with cracks was introduced. In the condition of which the chimney has a 10m long crack and directional window could not be cut, the construction tech-nology and design about the blasting demolition of it were expounded with emphasis. By taking the col-lapsed scheme with small cut, large explosive unit consumption and the one-time initiation, designing rea-sonable blasting cut and blasting parameters, and adopting effective protective measures, the chimney col-lapsed toward design direction.

  4. Thoracic type Ia endoleak: direct percutaneous coil embolization of the aortic arch at the blood entry site after TEVAR and double-chimney stent-grafts

    International Nuclear Information System (INIS)

    To introduce a novel percutaneous technique to stop blood entry at the lesser aortic arch curvature by coil embolisation in type Ia endoleak after TEVAR. A 61-year-old Marfan patient presented with type Ia endoleak of the aortic arch and a growing aortic arch pseudoaneurysm after TEVAR. Multiple preceding operations and interventions made an endovascular approach unsuccessful. Direct percutaneous puncture of the aneurysmal sac would have cured the sign, but not the cause of blood entry at the lesser curvature of the aortic arch. Direct CT-guided percutaneous puncture of the blood entry site in the aortic arch with fluoroscopically guided coil embolisation using detachable extra-long coils was successfully performed. Three weeks after the intervention, the patient developed fever because of superinfection of the pseudoaneurysm. The blood cultures and CT-guided mediastinal aspirate were sterile. After intravenous administration of antibiotics, the fever disappeared and the patient recovered. Six-month follow-up showed permanent closure of the endoleak and a shrinking aneurysmal sac. Direct percutaneous puncture of the aortic arch at the blood entry site of a thoracic type Ia endoleak after TEVAR and double-chimney stent-grafts with coil embolisation of the wedge-shaped space between the lesser aortic curvature and the stent-graft is possible. (orig.)

  5. Characterization of Alkaliphilus hydrothermalis sp. nov., a novel alkaliphilic anaerobic bacterium, isolated from a carbonaceous chimney of the Prony hydrothermal field, New Caledonia.

    Science.gov (United States)

    Ben Aissa, Fatma; Postec, Anne; Erauso, Gaël; Payri, Claude; Pelletier, Bernard; Hamdi, Moktar; Fardeau, Marie-Laure; Ollivier, Bernard

    2015-01-01

    A novel anaerobic, alkaliphilic, Gram-positive staining bacterium was isolated from a hydrothermal chimney in the Prony Bay, New Caledonia. This strain designated FatMR1(T) grew at temperatures from 20 to 55 °C (optimum 37 °C) and at pH between 7.5 and 10.5 (optimum 8.8-9). NaCl is not required for growth (optimum 0.2-0.5%), but is tolerated up to 3%. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite are not used as terminal electron acceptors. Strain FatMR1(T) fermented pyruvate, yeast extract, peptone and biotrypcase and used fructose as the only sugar. The main fermentation products from fructose and proteinaceous compounds (e.g. peptone and biotrypcase) were acetate, H2 and CO2. Crotonate was disproportionated to acetate and butyrate. The predominant cellular fatty acids were C14:0 and C16:0. The G + C content of the genomic DNA was 37.1 mol%. On the basis of phylogenetic, genetic, and physiological properties, strain FatMR1(T) (=DSM 25890(T), =JCM 18390(T)) belonging to the phylum Firmicutes, class Clostridia, order Clostridiales, is proposed as a novel species of the genus Alkaliphilus, A. hydrothermalis sp. nov. PMID:25319677

  6. Chimney Height Optimization for the Ultra Low Emission Power Plant%超低排放电厂烟囱高度优化研究

    Institute of Scientific and Technical Information of China (English)

    熊宏亮

    2015-01-01

    After today's large-scale coal-fired power plants taking a series of strict air pollution control measures, the emissions of major air pollutants achieve ultra-low emission requirements. SCREEN3 estimation model is used to predict the maximum concentration of landing and the emergence distance of air pollutants under different stack heights, the chimney height is optimized and proved, which provides reference for the EIA.%现今大型燃煤火力发电厂采取一系列严格的大气污染防治措施后,主要大气污染物排放达到超低排放要求。在此前提下,利用SCREEN3估算模式预测不同烟囱高度下主要大气污染物最大落地浓度及出现距离,对烟囱高度进行了优化论证,为工程环评提供参考。

  7. Thoracic type Ia endoleak: direct percutaneous coil embolization of the aortic arch at the blood entry site after TEVAR and double-chimney stent-grafts

    Energy Technology Data Exchange (ETDEWEB)

    Bangard, Christopher; Franke, Mareike; Maintz, David; Chang, De-Hua [University Hospital, University of Cologne, Department of Radiology, Cologne (Germany); Pfister, Roman [University Hospital, University of Cologne, Department of Internal Medicine III, Cologne (Germany); Deppe, Antje-Christin [University Hospital, University of Cologne, Department of Cardiothoracic Surgery, Cologne (Germany); Matoussevitch, Vladimir [University Hospital, University of Cologne, Department of Vascular Surgery, Cologne (Germany)

    2014-06-15

    To introduce a novel percutaneous technique to stop blood entry at the lesser aortic arch curvature by coil embolisation in type Ia endoleak after TEVAR. A 61-year-old Marfan patient presented with type Ia endoleak of the aortic arch and a growing aortic arch pseudoaneurysm after TEVAR. Multiple preceding operations and interventions made an endovascular approach unsuccessful. Direct percutaneous puncture of the aneurysmal sac would have cured the sign, but not the cause of blood entry at the lesser curvature of the aortic arch. Direct CT-guided percutaneous puncture of the blood entry site in the aortic arch with fluoroscopically guided coil embolisation using detachable extra-long coils was successfully performed. Three weeks after the intervention, the patient developed fever because of superinfection of the pseudoaneurysm. The blood cultures and CT-guided mediastinal aspirate were sterile. After intravenous administration of antibiotics, the fever disappeared and the patient recovered. Six-month follow-up showed permanent closure of the endoleak and a shrinking aneurysmal sac. Direct percutaneous puncture of the aortic arch at the blood entry site of a thoracic type Ia endoleak after TEVAR and double-chimney stent-grafts with coil embolisation of the wedge-shaped space between the lesser aortic curvature and the stent-graft is possible. (orig.)

  8. 湿法脱硫系统混凝土烟道内防腐蚀方案%Anticorrosion Scheme for Concrete Chimney in Flue Gas Desulphurization System

    Institute of Scientific and Technical Information of China (English)

    何思立; 李建三; 龙乃健; 曾松峰

    2014-01-01

    The corrosion behavior of bare common concrete,bare ceramsite concrete and test blocks with modified epoxy liner anticorrosion coating was studied in concrete chimney of flue gas desulphurization systems.Blister of the coating and other obvious changes did not appear on the epoxy liners after 6 months test.No any corrosion indication happened to the rebar in concrete block with epoxy liner anticorrosion coating,indicating a good protection to the rebar in concrete block.After 6 months test,the chlorine element in concrete block with epoxy liners was not found by the analysis result of energy dispersive spectrometer,and the content of sulfur did not increase compared with the untested concrete block.The results showed that the epoxy liner anticorrosion coating could prevent the permeation of harmful corrosives and provide the concrete block with very good protection.The results of engineering application experiment also proved the very good protection of epoxy liner anticorrosion scheme for concrete chimney in flue gas desulphurization systems.%采用改性环氧配套衬里的方案制备防腐蚀层。对普通混凝土试样与陶粒砼试样及防腐蚀层在脱硫系统烟道内的现场腐蚀行为进行试验研究。试验6个月后环氧配套衬里层没有鼓泡烧蚀,未观察到明显的变化。采用环氧配套衬里防腐蚀层的混凝土试块,在试验6个月后其内部的钢筋未发现腐蚀现象,表明环氧配套衬里对混凝土中的钢筋起到了较好的保护作用。试验6个月后环氧配套衬里混凝土样的能谱结果均未检测到氯元素,硫元素的含量同未试验的对比测试样相比也未增加,表明环氧配套衬里对混凝土起到了很好的保护作用。工程应用结果表明,改性环氧配套衬里的防腐蚀方案能够对湿法脱硫系统的混凝土烟道起到很好的防腐蚀保护作用。

  9. Psychology and photography: chimneys dreaming and chimneys warriors

    OpenAIRE

    Tilde Giani Gallino

    2013-01-01

    The article covers two aspects related to Psychology and Art. The first aspect concerns the similarities found between photography and various Schools of experimental psychology. For instance, the scientists of Psychology of ethological theory, and Non-verbal communication (NVC), observe with particular methodologies the non-verbal messages that animals and humans transmit to their peers through expressions, posture, gestures. The same is done by photographers (those who use the “camera” with...

  10. 60m高密度单层布筋钢筋砼烟囱的爆破拆除%Explosive Demolition of 60 m High Density Single Layer Reinforced Concrete Chimney

    Institute of Scientific and Technical Information of China (English)

    张洁升; 程才林

    2011-01-01

    The explosive demolition of 60 m high reinforced concrete chimney in Hangzhou iron and steel group company was very difficult because of its single steel layer with coarse vertical and high density steels. It is very nec essary to test in reasonable point for the success of blasting. The reasonable specific charge and the charge amount each hole can be detemined by analysising test blasting. Meantime, the pretreatment and pre - cut to steel network are added under ensuring the stability of the chimney structure. The result show that above measures are feasible and necessary.%杭钢60m钢砼烟囱的爆破拆除,因其为单层布筋,竖筋粗,且布筋密度高,而成为本次爆破的难点.为确保爆破的成功,选择了合适部位进行试爆.根据试爆情况分析,确定合理炸药单耗及单孔药量.同时,在确保烟囱结构稳定的情况下,增加了对钢筋网的预处理、预切割内容.爆破结果表明,该措施是可行,且必要的.

  11. Entransy dissipation based performance analysis for solar chimney power plant system with vertical collectors%基于火积耗散法的立式集热板太阳能热气流发电系统传热性能分析

    Institute of Scientific and Technical Information of China (English)

    周艳; 刘峰; 王莉; 巢军; 李庆领

    2015-01-01

    On the basis of the principle of entransy dissipation and the principle of minimum thermal resist-ance in heat transfer theory,the expression of entransy dissipation rate of the solar chimney power plant system with vertical collectors was derived and the heat transfer performance of this system was analyzed. The results show that,the structure dimensions of the chimney are the main factors affecting the perform-ance of the solar chimney power plant system with vertical collectors.However,the height and width of the solar chimney are limited by the height and space between the windows of high buildings,thus the thick-ness of the solar chimney is the foremost factor to decrease the entransy dissipation of the solar power plant system.Under conditions with constant chimney height and width,the thermal resistance of entransy dissipation of the solar system reached the minimum when the solar chimney thickness was 0.959 8 m,indi-cating the performance of the system achieved the optimum.%基于火积耗散及火积耗散热阻极值定律推导出立式集热板太阳能热气流发电系统的火积耗散率表达式,并对系统的传热性能进行分析.结果表明:立式集热板太阳能热气流发电系统的烟囱尺寸是影响系统传热性能的主要因素,但是烟囱的高度和宽度受高层建筑的高度及窗户间距的限制,因此烟囱厚度成为系统火积耗散热阻的主要影响因素;在烟囱高度和宽度不变的条件下,厚度取0.9598 m 时系统火积耗散热阻最小,系统性能最优.

  12. 基于火积耗散法的立式集热板太阳能热气流发电系统传热性能分析%Entransy dissipation based performance analysis for solar chimney power plant system with vertical collectors

    Institute of Scientific and Technical Information of China (English)

    周艳; 刘峰; 王莉; 巢军; 李庆领

    2015-01-01

    基于火积耗散及火积耗散热阻极值定律推导出立式集热板太阳能热气流发电系统的火积耗散率表达式,并对系统的传热性能进行分析.结果表明:立式集热板太阳能热气流发电系统的烟囱尺寸是影响系统传热性能的主要因素,但是烟囱的高度和宽度受高层建筑的高度及窗户间距的限制,因此烟囱厚度成为系统火积耗散热阻的主要影响因素;在烟囱高度和宽度不变的条件下,厚度取0.9598 m 时系统火积耗散热阻最小,系统性能最优.%On the basis of the principle of entransy dissipation and the principle of minimum thermal resist-ance in heat transfer theory,the expression of entransy dissipation rate of the solar chimney power plant system with vertical collectors was derived and the heat transfer performance of this system was analyzed. The results show that,the structure dimensions of the chimney are the main factors affecting the perform-ance of the solar chimney power plant system with vertical collectors.However,the height and width of the solar chimney are limited by the height and space between the windows of high buildings,thus the thick-ness of the solar chimney is the foremost factor to decrease the entransy dissipation of the solar power plant system.Under conditions with constant chimney height and width,the thermal resistance of entransy dissipation of the solar system reached the minimum when the solar chimney thickness was 0.959 8 m,indi-cating the performance of the system achieved the optimum.

  13. 某加热炉烟囱深基坑支护难点及对策%Difficulties and Solutions in the Deep Foundation Excavation Retaining for a Heating Furnace Chimney

    Institute of Scientific and Technical Information of China (English)

    唐川

    2012-01-01

    A chimney foundation consists of two heating furnace chimney foundations. The depth of soil excavation reaches about 9.9 meters. The foundation is adjacent to a road with dynamic load of 600kN. And the foundation construction was during the rainy season of Shanghai, which causes extra danger to the excavation. This paper analyzes the key technology and construction difficulties of the engineering. The SMW method was used in combination with bracings, which successfully ensures the excavation safety and avoided any influence to the road traffic. This paper also analyzes the construction difficulties and compares different solutions.%某烟囱基础由2座加热炉烟囱基础组成,土方开挖深度达9.9m.基础紧邻道路,道路动荷载达600kN,同时基坑开挖正赶上上海的梅雨季节,基坑开挖过程中对安全十分不利.针对深基坑支护这一课题,分析了该工程的关键技术及难点,选择了SMW工法与斜撑结合的方案,实现既不影响深基坑安全,又不影响道路通行的目标.同时对加热烟囱深基坑施工的难点和对策进行了分析对比.

  14. Sulfurovum aggregans sp. nov., a hydrogen-oxidizing, thiosulfate-reducing chemolithoautotroph within the Epsilonproteobacteria isolated from a deep-sea hydrothermal vent chimney, and an emended description of the genus Sulfurovum.

    Science.gov (United States)

    Mino, Sayaka; Kudo, Hideaki; Arai, Takayuki; Sawabe, Tomoo; Takai, Ken; Nakagawa, Satoshi

    2014-09-01

    A novel mesophilic, strictly hydrogen-oxidizing, sulfur-, nitrate- and thiosulfate-reducing bacterium, designated strain Monchim33(T), was isolated from a deep-sea hydrothermal vent chimney at the Central Indian Ridge. The non-motile, rod-shaped cells were Gram-stain-negative and non-sporulating. Growth was observed between 15 and 37 °C (optimum 33 °C; 3.2 h doubling time) and between pH 5.4 and 8.6 (optimum pH 6.0). The isolate was a strictly anaerobic chemolithoautotroph capable of using molecular hydrogen as the sole energy source and carbon dioxide as the sole carbon source. The G+C content of the genomic DNA was 42.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel isolate belonged to the genus Sulfurovum and was closely related to Sulfurovum sp. NBC37-1 and Sulfurovum lithotrophicum 42BK(T) (95.6 and 95.4 % similarity, respectively). DNA-DNA hybridization demonstrated that the novel isolate could be differentiated genotypically from Sulfurovum sp. NBC37-1 and Sulfurovum lithotrophicum. On the basis of the molecular and physiological traits of the new isolate, the name Sulfurovum aggregans sp. nov. is proposed, with the type strain Monchim33(T) ( = JCM 19824(T) = DSM 27205(T)).

  15. Experimental study on heat storage layers of solar chimney power generation systems%太阳能烟囱发电系统蓄热层的试验研究

    Institute of Scientific and Technical Information of China (English)

    左潞; 郑源; 沙玉俊; 李振杰; 刘文明

    2011-01-01

    搭建了3台带有不同石块蓄热介质蓄热层的太阳能烟囱发电系统对比试验装置,在实际天气条件下,对该装置的运行性能进行了测试,并对试验结果进行了对比分析.结果表明:石块蓄热层具有储存热量的能力,随着蓄热层深度的增加,蓄热层内温度随外界影响就越小.系统内热气流的温升主要在集热棚的中前段,不同时间层热气流温升幅度不同.辐射强度、辐射时间和其他环境因素及集热棚集热性状都会对热气流温升产生一定的影响.石块蓄热材料的热容量和导热系数对蓄热层的平均温度和蓄热量影响较大,热容量大,蓄热层的平均温度日夜变化幅度相对较小,对于太阳能烟囱发电系统的发电峰谷差的调整有利.用同种石块作为集热和蓄热材料时,应合理选择石块材料的粒径和孔隙率,适当增大粒径和孔隙率可增强蓄热层的蓄热能力,有利于提高蓄热层的平均温度.没有太阳辐射时,蓄热层储存的热量能更好地加热气流.%Three solar chimney power generation systems with heat storage layers of different stone heat storage media were constructed. The operation performances of the systems under actual weather conditions were tested, and the resuts were compared and analyzed. The test results show that the stone heat storage layer has heat storage capacity. With the increaesing depth of the storage layer, the effects of the environment on the temperature of the heat storage layer is smaller and smaller. The temperature rise of heat air flow in the system is mainly in the middle and front parts of the heat collector and its amplitude is different at different time levels. The radiation intensity, irradiation time, other environmental factors and heat storage characteristics of heat collectors all have certain influences on the temperature rise of heat air flow. The heat capacity and conductivity of stone heat storage materials have great

  16. Un-landing Construction Technology of Entire Suspension Steel Inside Tube of Chenjiagang Power Plant Chimney%陈家港电厂烟囱整体悬吊钢内筒非落地施工技术

    Institute of Scientific and Technical Information of China (English)

    王瓅玮; 王德闯

    2011-01-01

    The steel inside tube of the chimney of Chenjiagang power plant is the first entire suspension steel inside tube in China. Because of the special form with high requirement of safety and quality, the method of hydraulic synchronous lifting is taken. The installation of steel inside tube, transferring of lifting points and tube hanging are introduced in detail. Through finite element analysis, the weak points of the lifting points and tube during construction are checked, and all the stiffness and strength can meet requirement. Meanwhile, according to the characteristics of thin wall, large weight and un-landing of steel inside tube, the idea that transferring lifting points in the air is put forward. By continuously monitoring, un-landing construction is completed successfully.%陈家港电厂烟囱钢内筒是国内首例整体悬吊式钢内筒.由于整体悬吊形式的安全质量要求高,采用了液压同步提升方案.重点介绍了钢内筒安装、吊点转换、筒体悬挂等施工工艺.通过运用有限元分析,对施工过程中吊点和简体的薄弱点进行验算,得出所有吊点的强度和刚度均满足要求.同时,根据钢内筒筒壁薄、质量大、不能落地的特点,提出了空中转换吊点的理念,通过施工中的不断监测,顺利完成了钢内筒的非落地施工.

  17. “烟囱”技术在治疗累及主动脉弓分支动脉的Stanford B型主动脉夹层中的应用%Endovascular aortic repair plus chimney technique in the treatment of Stanford type B aortic dissection involving aortic arch

    Institute of Scientific and Technical Information of China (English)

    舒畅; 王暾; 黎明; 李鑫; 李全明; 方坤

    2012-01-01

    Objective To evaluate the efficacy of endovascular aortic repair plus chimney technique in the treatment of Stanford type B aortic dissection involving aortic arch.Methods From June 2009 to March 2012,32 patients of aortic arch dissection with primary entry tear next to the orifices of supra-aortic arteries were treated with chimney technique.Chimney technique was used to reconstruct left subclavian artery (n =2) and left common carotid artery (n =28).Double chimney technique was use to reconstruct innominate artery and left common carotid artery simultaneously in 2 patients.Results Four patients received emergency operation.All patients survived and were followed up for 14.3 ± 7.4 months.No type Ⅰ endoleak occurred.Among 4 patients with Type Ⅱ endoleak,3 received PDA occluding implantation in left subclavian artery and 1 patient in puerperium with Marian syndrome and pregnancy-induced hypertension syndrome recovered by conservative treatment.No severe neurological complications and left subclavian artery ischemia occurred.The locations of aortic and chimney stent-grafts were stable without any migration.All stent-grafts remained patent.Conclusion Endovascular aortic repair plus chimney technique is a safe and effective treatment for Stanford type B aortic dissection involving aortic arch.%目的 探讨“烟囱”技术在累及主动脉弓部分支动脉的Stanford B型夹层的治疗作用.方法 对2009年6月至2012年3月中南大学湘雅二医院血管外科采用“烟囱”技术治疗的第一破口邻近主动脉弓部分支动脉起始端的32例Stanford B型主动脉夹层患者进行回顾性研究.“烟囱”技术重建左锁骨下动脉2例,重建左颈总动脉28例,采用“双烟囱”技术同时重建无名动脉和左颈总动脉2例.结果 急诊手术4例.手术成功率100%,无Ⅰ型内漏发生.4例发生左锁骨下动脉Ⅱ型内漏,3例采用PDA封堵器封堵内漏,1例合并Marfan综合征和妊高症,予以保守治疗,11

  18. CHIMNEY TECHNOLOGY IN STANFORDB TYPE OF ABDOMINAL AORTIC ANEURYSM AND AORTIC DISSECTION INVOLVING THE CLINICAL APPLICATION OF RENAL ARTERY PROSTHESIS%烟囱技术在 StanfordB 型主动脉夹层和腹主动脉瘤累及肾动脉修复术的临床应用

    Institute of Scientific and Technical Information of China (English)

    王厚生

    2015-01-01

    Objective Type chimney technology in StanfordB abdominal aortic aneurysm and aortic dis‐section involving the renal artery (juxtarenal aortic aneurysms ,JAA) application feasibility and safety of repair .Methods Jan 2010 to jan 2013 ,21 cases of diagnosis and treatment of abdominal aortic aneurysm and aortic dissection StanfordB type involving patients with renal artery ,w hich StanfordB type ,including 13 cases of aortic dissection ,abdominal aortic aneurysm involvement of 8 cases of renal artery .All patients were performed CT enhanced scan ,before they are confirmed by femoral artery puncture aortic angiogra‐phy ,coated stents improperness internal isolation in parallel "chimney" technology to protect important branch artery .Results All patients were successfully repair the aorta and guarantee important branch such as subclavian artery and renal artery flow .Conclusion The clinical application of "chimney" technology solves the lumen of isolated from surgery to repair the aortic lesions at the same time avoid the other im‐portant branch of isolated vascular perfusion ,and to solve the primary disease of coated stent provides ef‐fective proximal anchoring area , even can help eliminate the leakage , to ensure the operation curative effect .%目的:探讨烟囱技术在StanfordB型主动脉夹层和腹主动脉瘤累及肾动脉(juxtarenal aortic aneurysms ,JAA)修复术的应用的可行性和安全性。方法2010年01月至2013年01月诊治21例StanfordB型主动脉夹层和腹主动脉瘤累及肾动脉的患者,其中StanfordB型主动脉夹层13例,腹主动脉瘤累及肾动脉8例。所有患者均行先C T 增强扫描,后经股动脉穿刺主动脉造影证实,植入覆膜支架行腔内隔绝术并行“烟囱”技术保护重要分支动脉。结果所有患者均成功修复主动脉并保证重要分支动脉如锁骨下动脉和肾动脉通畅。结论“烟囱”技术的临床应用解决了腔内隔绝术修复主动

  19. Reverse crossover chimney technique combined with endovascular aneurysm repair treating abdominal aortic aneurysm%腹主动脉瘤腔内修复术联合腔内反向髂内动脉覆膜支架置入术临床观察

    Institute of Scientific and Technical Information of China (English)

    李彭; 郭曦; 黄小勇; 李铁铮; 韩晓峰; 刘光锐; 薛玉国; 蒲俊舟; 黄连军

    2014-01-01

    目的 探讨腹主动脉瘤腔内修复术联合反向髂内动脉覆膜支架置入术治疗腹主动脉瘤的疗效.方法 自2013年4-6月,于北京安贞医院行腹主动脉瘤腔内修复术联合反向髂内动脉覆膜支架置入术的患者共3例,均为男性,年龄分别为57、66、65岁,采用双侧切开暴露股动脉,对侧送导丝置入转流侧髂内动脉内保留,依次送入腹主动脉支架主体、髂分支及转流支架并分别完全释放.结果 腹主动脉支架选择ENDURANT(Medtronic,美国)或EXCLUDER(GORE,美国)的2例患者转流支架内可见造影剂充盈,转流侧髂内动脉及其分支显影良好,另1例腹主动脉支架选择Zenith(COOK,美国)的患者自转流支架开口处闭塞.术后1个月CT血管造影显示所有患者未出现支架内漏和支架移位等并发症.结论 对于腹主动脉瘤累及双侧髂动脉需行腔内修复术并覆盖双侧髂内动脉患者,同时并行反向髂内动脉腔内覆膜支架置入术能够保护单侧髂内动脉,但还需进一步扩大病例数以分析影响转流支架通畅的因素,并进行长期随访观察远期疗效.%Objective To investigate the curative effect of reverse crossover chimney technique combined with endovascular aneurysm repair treating abdominal aortic aneurysm.Methods Three cases (3 males,average age:57,66,65 years old) received endovascular aneurysm repair(EVAR) and reversed crossover chimney technique in abdominal aortic aneurysm.The vascular stent was sent from contralateral femoral artery.After intervention,digital subtraction angiography showed that abdominal aortic aneurysm was repaired ; bypass-stent and ipsilateral inner iliac artery were unobstructed.Results Contrast medium was fully filled in abdominal aorta and the abdominal aorta was well displayed in 2 cases using bypass-stent,ENDURANT (Medtronic,USA) or EXCLUDER (GORE,USA).The ipsilateral inner iliac artery was also well displayed.Abdominal aorta was obstructed in the opening

  20. 太阳能烟囱与露点间接蒸发冷却复合空调节能系统分析%Analysis of an Energy Saving Air Conditioning System Integrated with Solar Chimney and Dew-point Evaporative Cooling

    Institute of Scientific and Technical Information of China (English)

    倪诚明

    2014-01-01

    太阳能烟囱是一种热压作用下的自然通风设备,它利用太阳辐射作为动力,为空气流动提供浮升力,将热能转化为动能。露点间接蒸发冷却技术利用空气的干球温度和不断降低的湿球温度之差进行换热,可以将空气温度冷却到低于环境湿球温度且接近露点温度。本文介绍了太阳能烟囱与露点间接蒸发冷却技术的研究现状,提出一套太阳能烟囱与露点间接蒸发冷却复合的空调节能系统。分析表明,该系统可合理的利用太阳能解决室内通风降温问题,投资和运行费用都很低,节能环保效果显著。%Solar chimney is a kind of natural ventilation application under the action of hot pressing, it using solar radiation as power, providing buoyancy lift for air flow, transfer the thermal energy into kinetic energy.The technol-ogy of dew-point evaporative cooling using the temperature difference of air between dry bulb temperature and low-ing wet bulb temperature to transfer heat.Its able to cool air to temperature below ambient wet bulb temperature and approaching dew-point temperature.This paper review the research status of solar chimney and dew-point evapora-tive cooling.The analysis results showed that the proposed system is a reasonable way to solve the indoor ventilation and cooling problems.its investment and operating cost is lower, and has a remarkable energy saving and environ-ment protection effect.

  1. Chimney Grafts of Renal Artery for Endovascular Repair of Juxta-renal Aortic Aneurysms with Complex Aneurysm Neck%复杂瘤颈的近肾腹主动脉瘤腔内修复中烟囱技术的应用

    Institute of Scientific and Technical Information of China (English)

    宋小军; 刘昌伟; 刘暴; 吴巍巍; 郑日宏; 陈宇

    2012-01-01

    Objective To investigate the value of chimney grafts of renal artery in endovascular aneurysm repair (EVAR) of Juxta-renal aortic aneurysms ( JAA) with complex aneurysm neck. Methods Totally 7 patients with JAA were treated by EVAR with chimney grafts between January 2007 and October 2011 at our department. All the cases were unsuitable for standard endovascular abdominal aortic aneurysm ( AAA) repair because of large neck angulation. And they were of high-risk for open repair because of poor health state. During the procedure, by brachial artery puncture, we introduced a guide wire trough the renal artery that could be covered by the stent graft. And then, after the stem was placed, self-expandable rtent or balloon expandable stent was inserted so that to lengthen the aneurysm neck for EVAR and protect the renal artery. Results The success rate of the procedure was 100%. Totally 9 renal artery stem were used, including 5 balloon expandable stents and 4 self-expandable stenta. Angiography at the end of the operation showed normal renal blood flow into the kidney and well-separated AAA. One patient developed type Ⅰ endoleak, which was cured with a Cuff. One patient showed mild type Ⅱ endoleak without needing treatment. The patients were followed up for a mean of 11.6 months (1-52 months) , during which one patient died of heart failure in two months, the type Ⅱ endoleak disappeared in three months, and all the chimney grafts were kept patent through the follow-up. Conclusions The chimney graft of the renal artery is an alternative of conventional EVAR, it is suitable for JAA patients with unfavourable aortic anatomy. Further study is necessary to observe its long-term outcomes.%目的 探讨瘤颈解剖复杂的近肾腹主动脉瘤(juxtarenal aortic aneurysms,JAA)腔内修复(endovascular aneurysm repair,EVAR)中应用烟囱技术的价值. 方法 2007年1月~2011年10月,对7例瘤颈复杂的JAA采用EVAR治疗.由于瘤颈解剖结构不适于标准的

  2. Chimney technique in left subclavian artery during the procedures of endovascular aortic repair for the Stanford type B aortic dissection%左锁骨下动脉烟囱技术在Stanford B型胸主动脉夹层腔内修复术中的应用

    Institute of Scientific and Technical Information of China (English)

    练辉; 陈德基; 林少芒; 张东诚

    2014-01-01

    目的:探讨左锁骨下动脉烟囱技术在Stanford B型主动脉夹层腔内修复术(EVAR)中的意义和技术要点。方法回顾性分析35例临床和影像学确诊的Stanford B型主动脉夹层,且主动脉撕裂累及到左锁骨下动脉的患者,以CTA作为术前评估方法,术中覆膜支架覆盖左锁骨下动脉,以球囊扩张支架对左锁骨下动脉进行介入再通。结果35例胸主动脉覆膜支架和左锁骨下动脉球囊扩张支架均放置成功,术后随访3~24个月,35例左锁骨下动脉烟囱支架通畅率100%。结论 Stanford B型胸主动脉夹层的EVAR治疗时,覆膜支架的近侧锚定区选择在正常的主动脉壁,可以降低继发医源性夹层的发生;覆盖左锁骨下动脉后采用烟囱技术可有效预防“盗血综合征”的发生,其技术简捷、安全。%Objective To discuss the meaning and technical key points of the chimney technique in left subclavian artery during the procedures of endovascular aortic repair (EVAR) for the Stanford type B aortic dissection. Methods A total of 35 patients with type B aortic dissection diagnosed by clinical and imaging assessments, whose left subclavian artery was involved by dissection, were retrospectively analyzed. All the cases were assessed by CTA before EVAR, their left subclavian arteries were covered by the deployments of stent grafts. The occlusive arteries were recanalized by balloon expanding stents. Results The placements of aortic stent grafts and subclavian arterial stents were successful in all the 35 cases. All the left subclavian arteries were opened during 3—24 months follow-up. The recanalized rate was 100%. Conclusion In the procedures of EVAR the proximal anchoring zone of stent grafts should be chosen in the normal vascular wall to prevent from available dissection caused by therapies. After the deployments of stent grafts which covered left subclavian arteries, the recanalization with chimney technique can

  3. 77 FR 59275 - Establishment of the Chimney Rock National Monument

    Science.gov (United States)

    2012-09-27

    ... Documents #0; #0; #0;#0;Federal Register / Vol. 77 , No. 188 / Thursday, September 27, 2012 / Presidential Documents#0;#0; #0; #0;Title 3-- #0;The President ] Proclamation 8868 of September 21, 2012 Establishment of... multi-room ``great house'' built in the late eleventh century to command observations of the...

  4. Korsten : tellimata tellised = Chimney : an outside job / Andres Aule

    Index Scriptorium Estoniae

    Aule, Andres

    2012-01-01

    Aap Kaur Suvi kavandatud Tallinna linnainstallatsioonide festivali "LIFT11" installatsioonist "Korsten", mis pidi seisnema Tauno Kangro skulptuuri "Lõbus korstnapühkija" ümber ajutise telliskorstna ehitamises. Lift11 jättis selle installatsiooni ära, kuid ootamatult sai "Korsten" kodanikualgatusena 8. IX 2011 teoks

  5. Social Criticism in The Chimney Sweeper by William Blake

    Institute of Scientific and Technical Information of China (English)

    朱晓芸

    2008-01-01

    This paper mainly focuses on social criticism in William Blake's poems,both entitled"The Chimnet SWeeper"by analy-zing social background at that time and different Views in these two poems.It also tries to embody a fuller effect in thesc two separate poems.

  6. Project Rio Blanco - Part II: Production test data and preliminary analysis of top chimney/cavity

    International Nuclear Information System (INIS)

    The re-entry drilling established communication with the top Rio Blanco detonation region at a depth of 1704 m, or about 76 m above the top detonation centre. A total of 2.8 x 106m3(97 x 106ft3) of dry gas at standard conditions has now been produced during two separate test periods. Radioactive and chemical analysis of this gas and the modelling of the stimulated reservoir shows the following main result: (1) No permeable connection exists between the top and the middle detonation regions, since none of the tracer incorporated in the centre explosive canister was detected in the gas produced. As a consequence, results for the top detonation region only are available at this time; (2) The initial cavity radius is deduced to be 20 m(66 ft), or well within expectations; (3) Integration of the 85Kr produced indicates a yield of 34+-3kt for the top explosive; (4) Of the approximately 1000 Ci of tritium produced in the top explosion region, about 5% is incorporated in the gas phase, (5) Pressure draw-down and build-up data are best reproduced by a two-layer reservoir model showing stimulated permeabilities about 10 and 30 times original formation permeabilities, and extending to a distance of about three cavity radii from the well bore; (6) The capacity of the reservoir intercepted by the top explosive is deduced to be about 0.2 mdarcy.m(0.73 mdarcy.ft), as contrasted with pre-shot estimates ranging from 1.3 to 2.3 mdarcy.m(4.1 - 7.6 mdarcy.ft). The reason for this discrepancy is not resolved at this time. Additional subsurface investigations of the other detonation regions as well as a re-evaluation of the initial reservoir properties are in progress. (author)

  7. Production test data and preliminary analysis of top chimney/cavity

    International Nuclear Information System (INIS)

    The reentry drilling established communication with the top Rio Blanco detonation region at a depth of 1704 m, or approximately 76 m above the top detonation center. A total of 2.8 x 106 m3 (98 x 106 ft3) of dry gas at standard conditions has now been produced during two separate test periods. Radioactive and chemical analysis of this gas and the modeling of the stimulated reservoir show the following main results: 1. No permeable connection exists between the top and the middle detonation regions, since no significant amount of the tracer incorporated in the center explosive canister was detected in the produced gas. As a consequence, results for the top detonation region only are available at this time. 2. The initial cavity radius is deduced to be 20 m (66 ft) or well within expectations. 3. Integration of the 85Kr produced indicates a yield of 34 +- 3 kt for the top explosive. 4. Of the approximately 1000 Ci of tritium produced in the top explosion region, approximately 5 percent is incorporated in the gas phase. 5. Pressure drawdown and buildup data are best reproduced by a two-layer reservoir model showing stimulated permeabilities approximately 10 and 30 times original formation permeabilities, and extending to a distance of approximately 3 cavity radii from the wellbore. 6. The capacity of the reservoir intercepted by the top explosive is deduced to be approximately 0.2 millidarcymeters (md-m) [0.73 millidarcy-feet (md-ft)], as contrasted with preshot estimates ranging from 1.3 md-m (4.1 md-ft) to 2.3 md-m (7.6 md-ft). Additional subsurface investigations of the other detonation regions, as well as a reevaluation of the initial reservoir properties, are in progress. (auth)

  8. Physico-chemical gradients within the hydrothermal chimney Roane define sharp boundaries for microbial community ecology

    Science.gov (United States)

    Frank, K. L.; Kelley, D. S.; Girguis, P. R.

    2011-12-01

    The unique physico-chemical gradients characteristic of hydrothermal vents provide diverse niches for prokaryotic communities. To date, our knowledge of environmental constraints on microbial colonization and metabolic activity within active sulfide structures has been limited by the lack of co-registered in situ chemistry and appropriate, taxonomic and metabolic genetic markers. Here we characterize de novo endolithic microbial colonization using a sulfide microbial incubator within the hydrothermal vent Roane during a one-year deployment, with co-registered temperature, fluid chemistry and mineralogy. Taxanomic assessment of phylogenetic diversity via 16S rDNA extracted from the outer (40-70°C) and middle (150-240°C) chambers of the incubator revealed patterns of distribution comparable to previously published observations. However, quantitative and statistical analyses of 16S rDNA sequences from two chambers revealed very distinct communities, with less than 5% of the identified operational taxonomic units common to both chambers. Analyses of metagenomic data suggest an elevated potential for motility and select biosynthetic pathways in the outer chamber community. In contrast, the middle chamber community exhibits a greater potential for quorum sensing, biofilm formation and archaeal lipid biosynthesis. Striking differences in metabolic potential were also apparent. These data suggest that the distribution, abundance and physiological capacity of these communities is strongly governed by chemical and physical variability of the environment.

  9. 78 FR 72060 - Chimney Rock National Monument Management Plan; San Juan National Forest; Colorado

    Science.gov (United States)

    2013-12-02

    ... impact statement. SUMMARY: The Forest Service intends to prepare an environmental impact statement (EIS... archaeology, archaeoastronomy, visual and landscape characteristics, and geological and biological features... The draft environmental impact statement is expected in April, 2014 and the final environmental...

  10. Lightning, thermodynamic and hydrological comparison of the two tropical continental chimneys

    Science.gov (United States)

    Williams, E. R.; Sátori, G.

    2004-09-01

    The two major tropical continental zones of active convection-Africa and South America-are compared from the standpoint of lightning activity, rainfall, thermodynamics, hydrology and aerosol-influenced cloud microphysics. Comparisons of temperature, diurnal temperature range, insolation, Bowen ratio, response to semiannual forcing, inundation fraction, boundary layer relative humidity and associated cloud base height are all self consistent in showing a more continental surface for Africa than South America. These surface characteristics are shown to play a major role in the substantial contrast (annual ratio 2.8) in lightning flash rate density between the two major drainage basins in these two continents. The Congo is slightly hotter and slightly drier than the Amazon, with a contrast in wet bulb potential temperature and convective available potential energy that is difficult to resolve given limitations in the observations. Aerosol effects in cloud microphysics may be needed to account for quantitative shortfalls in explanations for lightning and rainfall on the basis of thermodynamics alone. Additional information about aerosols is needed to clarify their role. The clear African dominance in lightning and Schumann resonance intensity presents a paradox for the behavior of the `dc'global electrical circuit that is resolvable by dominance of electrified shower clouds in South America, as hypothesized by Wilson (Phil. Trans. A 221 (1920) 73).

  11. Metagenome and Metatranscriptome Revealed a Highly Active Sulfur Cycle in an Oil-Immersed Hydrothermal Chimney in Guaymas Basin

    OpenAIRE

    Ying eHe; Xiaoyuan eFeng; Jing eFang; Yu eZhang; Xiang eXiao

    2015-01-01

    The hydrothermal vent system is a typical chemosynthetic ecosystem in which microorganisms play essential roles in the geobiochemical cycling. Although it has been well recognized that the inorganic sulfur compounds are abundant and actively converted through chemosynthetic pathways, the sulfur budget in a hydrothermal vent is poorly characterized due to the complexity of microbial sulfur cycling resulting from the numerous parties involved in the processes. In this study, we performed an int...

  12. Composition of hydrothermal fluids and mineralogy of associated chimney material on the East Scotia Ridge back-arc spreading centre

    OpenAIRE

    James, Rachael H.; Green, Darryl R. H.; Stock, Michael J.; Alker, Belinda J.; Banerjee, Neil R.; Cole, Catherine; German, Christopher R.; Huvenne, Veerle A. I.; Powell, Alexandra M.; Connelly, Douglas P.

    2014-01-01

    The East Scotia Ridge is an active back-arc spreading centre located to the west of the South Sandwich island arc in the Southern Ocean. Initial exploration of the ridge by deep-tow surveys provided the first evidence for hydrothermal activity in a back-arc setting outside of the western Pacific, and we returned in 2010 with a remotely operated vehicle to precisely locate and sample hydrothermal sites along ridge segments E2 and E9. Here we report the chemical and isotopic composition of high...

  13. Combining interventions: improved chimney stoves, kitchen sinks and solar disinfection of drinking water and kitchen clothes to improve home hygiene in rural Peru L’association d’interventions - améliorer les cuisinières à bois, mettre en place des éviers, désinfecter l’eau domestique et le linge de cuisine par le solaire – permet d’améliorer l’hygiène dans les foyers ruraux du Pérou Intervenciones combinadas: mejorar las cocinas a leña, instalar fregaderos y desinfectar el agua para beber y los paños de cocina con energía solar para mejorar la higiene en hogares rurales en Perú

    Directory of Open Access Journals (Sweden)

    Ana I. Gil

    2012-05-01

    Full Text Available Home based interventions are advocated in rural areas against a variety of diseases. The combination of different interventions might have synergistic effects in terms of health improvement and cost effectiveness. However, it is crucial to ensure cultural acceptance. The aim of the study was to develop an effective and culturally accepted home-based intervention package to reduce diarrhoea and lower respiratory illnesses in children. In two rural Peruvian communities we evaluated the performance and acceptance of cooking devices, household water treatments (HWT and home- hygiene interventions, with qualitative and quantitative methods. New ventilated stove designs reduced wood consumption by 16%. The majority of participants selected solar water disinfection as HWT in a blind tasting. In-depth interviews on hygiene improvement further revealed a high demand for kitchen sinks. After one year of installation the improved chimney stoves and kitchen sinks were all in use.  The intervention package was successfully adapted to local customs, kitchen-, home- and hygiene management. High user satisfaction was primarily driven by convenience gains due to the technical improvements and only secondarily by perceived health benefits.Les interventions à domicile sont recommandées dans les zones rurales pour éviter diverses maladies. L’association de différentes interventions entraîne une synergie en termes d’amélioration de la santé et de rapport coût-efficacité. Il est cependant crucial d’obtenir l’adhésion de la population. Le but de l’étude était d'élaborer un programme d’interventions à domicile, efficaces et acceptées par la population, visant à réduire la diarrhée et les affections des voies respiratoires basses chez l’enfant. Nous avons évalué, dans deux communautés rurales du Pérou, l’efficacité et l’acceptation d’appareils de cuisson, des traitements de l’eau domestique (HWT et d’interventions d

  14. Metagenome and Metatranscriptome Revealed a Highly Active and Intensive Sulfur Cycle in an Oil-Immersed Hydrothermal Chimney in Guaymas Basin

    OpenAIRE

    He, Ying; Feng, Xiaoyuan; Fang, Jing; Zhang, Yu; Xiao, Xiang

    2015-01-01

    The hydrothermal vent system is a typical chemosynthetic ecosystem in which microorganisms play essential roles in the geobiochemical cycling. Although it has been well-recognized that the inorganic sulfur compounds are abundant and actively converted through chemosynthetic pathways, the sulfur budget in a hydrothermal vent is poorly characterized due to the complexity of microbial sulfur cycling resulting from the numerous parties involved in the processes. In this study, we performed an int...

  15. Microtexture and distribution of minerals in hydrothermal Barite-Silica chimney from the Franklin seamount, SW Pacific: Constraints on mode of formation.

    Digital Repository Service at National Institute of Oceanography (India)

    Ray, D.; Kota, D.; Das, P.; SuryaPrakash, L.; Khedekar, V.D.; Paropkari, A.L.; Mudholkar, A.V.

    on existing spheres. So it can be hypothesized that the growth of new spheres was likely started through partial melting of parent spheres wall in contact with hot volatile rich fluid inside. Thus fluid-flow channels connect the microspheres into chains....D. and Shevchenko, V.P., 1997. Hydrological and geochemical anomalies associated with hydrothermal activity in SW Pacific marginal and back-arc basins. Marine Geology 142, 7-45. Martinez, F., Taylor, B., Goodliffe, A., 1999. Contrusting styles of seafloor...

  16. Chimney stoves modestly improved indoor air quality measurements compared with traditional open fire stoves: results from a small-scale intervention study in rural Peru.

    Science.gov (United States)

    Hartinger, S M; Commodore, A A; Hattendorf, J; Lanata, C F; Gil, A I; Verastegui, H; Aguilar-Villalobos, M; Mäusezahl, D; Naeher, L P

    2013-08-01

    Nearly half of the world's population depends on biomass fuels to meet domestic energy needs, producing high levels of pollutants responsible for substantial morbidity and mortality. We compare carbon monoxide (CO) and particulate matter (PM2.5) exposures and kitchen concentrations in households with study-promoted intervention (OPTIMA-improved stoves and control stoves) in San Marcos Province, Cajamarca Region, Peru. We determined 48-h indoor air concentration levels of CO and PM2.5 in 93 kitchen environments and personal exposure, after OPTIMA-improved stoves had been installed for an average of 7 months. PM2.5 and CO measurements did not differ significantly between OPTIMA-improved stoves and control stoves. Although not statistically significant, a post hoc stratification of OPTIMA-improved stoves by level of performance revealed mean PM2.5 and CO levels of fully functional OPTIMA-improved stoves were 28% lower (n = 20, PM2.5, 136 μg/m(3) 95% CI 54-217) and 45% lower (n = 25, CO, 3.2 ppm, 95% CI 1.5-4.9) in the kitchen environment compared with the control stoves (n = 34, PM2.5, 189 μg/m(3), 95% CI 116-261; n = 44, CO, 5.8 ppm, 95% CI 3.3-8.2). Likewise, although not statistically significant, personal exposures for OPTIMA-improved stoves were 43% and 17% lower for PM2.5 (n = 23) and CO (n = 25), respectively. Stove maintenance and functionality level are factors worthy of consideration for future evaluations of stove interventions.

  17. Combining interventions: improved chimney stoves, kitchen sinks and solar disinfection of drinking water and kitchen clothes to improve home hygiene in rural Peru

    OpenAIRE

    Hartinger, Stella M.; Claudio F Lanata; Ana I. Gil; Hattendorf, Jan; Verastegui, Hector; Mäusezahl, Daniel

    2012-01-01

    Home based interventions are advocated in rural areas against a variety of diseases. The combination of different interventions might have synergistic effects in terms of health improvement and cost effectiveness. However, it is crucial to ensure cultural acceptance. The aim of the study was to develop an effective and culturally accepted home-based intervention package to reduce diarrhoea and lower respiratory illnesses in children. In two rural Peruvian communities we evaluated the performa...

  18. Automatic control of gaseous effluents emitted through the RP-10 reactor chimney; Control automatico de efluentes gaseosos emitidos por chimenea en el reactor RP-10

    Energy Technology Data Exchange (ETDEWEB)

    Castillo Y, Walter; Anaya G, Olgger; Ovalle S, Edgar [Instituto Peruano de Energia Nuclear, Lima (Peru)

    2002-07-01

    The ventilation system of the reactor, has a way in which should work in the event of a nuclear accident. Formerly the change to this emergency way was carried out in manual form manual, when the radioprotection official, detected during the control of the places that the radiation levels had been overcome, informing to the responsible of the control room, so that they change the ventilation system to the emergency way. Considering that this procedure was not the most appropriate for the retarded time in taking the measures correctives, we are decided to carry out in the design and implementation of an automatic system that it acquires the data of the radiation levels of the effluents that are evacuating to the environment, of the SEM1000 equipment and when the reference level is overcome, automatically the designed system will change the operation way the ventilation system to emergency, closing the exit to the exterior and putting it in the recirculation way, for it is used a micro controller PIC 16F877. On the other hand it has been taken to the control room the sign of the SEM1000, as a repeater with the same characteristics of the presentation of data of this equipment. (author)

  19. Diagnóstico de la resistencia de las chimeneas de los ciclones del Regenerador D-402 // Diagnostic of Regenerator D-402 Cyclones Chimneys Resistance.

    Directory of Open Access Journals (Sweden)

    Juan Miguel Pichardo-Martínez

    2009-09-01

    Full Text Available El presente artículo describe el modo en que se han empleado las técnicas de modelación encorrespondencia con el método de los Elementos Finitos, para la determinación de los esfuerzosmáximos que surgen en la zona de unión entre las chimeneas de los ciclones secundarios y laCámara Plenum del Regenerador D-402, de la Refinería de Petróleo “Ñico López”. El conjunto semodeló utilizando el software ABAQUS, donde se aplicaron las cargas críticas que pueden aparecer,en condiciones reales de trabajo.Palabras claves: modelación por elementos finitos, diagnóstico resistencia ciclones, regenerador d-402._______________________________________________________________________________AbstractThe paper describe the way modeling techniques have been employed, according to FiniteElements Analysis, for determining maximum stresses appearing in secondary cyclones chimneysand Plenum Chamber union of D-402 Regenerator, located in “Ñico López” Petroleum Refinery.ABAQUS software was applied for modeling. Critical loads taking place on real conditions weresimulated.Key words: finite elements analysis, cyclones resistance diagnostics, regenerator d-402

  20. 30 CFR 817.72 - Disposal of excess spoil: Valley fill/head-of-hollow fills.

    Science.gov (United States)

    2010-07-01

    ... precipitation event. (b) Rock-core chimney drains. A rock-core chimney drain may be used in a head-of-hollow... not located in an area containing intermittent or perennial streams. A rock-core chimney drain may be... is diverted around the fill. The alternative rock-core chimney drain system shall be...

  1. Fuel cell with internal flow control

    Science.gov (United States)

    Haltiner, Jr., Karl J.; Venkiteswaran, Arun

    2012-06-12

    A fuel cell stack is provided with a plurality of fuel cell cassettes where each fuel cell cassette has a fuel cell with an anode and cathode. The fuel cell stack includes an anode supply chimney for supplying fuel to the anode of each fuel cell cassette, an anode return chimney for removing anode exhaust from the anode of each fuel cell cassette, a cathode supply chimney for supplying oxidant to the cathode of each fuel cell cassette, and a cathode return chimney for removing cathode exhaust from the cathode of each fuel cell cassette. A first fuel cell cassette includes a flow control member disposed between the anode supply chimney and the anode return chimney or between the cathode supply chimney and the cathode return chimney such that the flow control member provides a flow restriction different from at least one other fuel cell cassettes.

  2. 主动脉弓上病变的双烟囱法腔内隔绝术%Endovascular exclusion with double-chimney technology for treating aortic arch pathologies

    Institute of Scientific and Technical Information of China (English)

    冯睿; 景在平; 赵志青; 魏小龙; 陆华; 王亮

    2011-01-01

    @@ 血管腔内隔绝术(endovascular exclusion,EVE)已经成为治疗主动脉夹层病主动脉瘤等主动脉扩张性疾病的成熟微创方法,可明显降低手术并发症和病死率,改善患者预后[1,2].但当病变累及主动脉弓上分支时,传统EVE由于无法保留分支血供而无法实施,而杂交手术、移植物开窗和分支技术也各有局限和缺陷.本文通过1例累及主动脉弓的EVE后I型内漏的治疗,介绍一种用于主动脉弓上病变治疗的双烟囱法EVE技术.

  3. Numerical simulation of sulfuric acid corrosion of concrete in power plant chimney%电站烟囱混凝土硫酸腐蚀的数值模拟

    Institute of Scientific and Technical Information of China (English)

    唐志永; 金保升; 孙克勤; 仲兆平

    2005-01-01

    研究了电站烟囱C30混凝土在80℃、质量分数为15%硫酸溶液浸泡条件下的腐蚀规律,根据Fick扩散方程和反应速率方程,提出一个简化的移动边界腐蚀模型.采用定时间步长和变坐标步长的差分求解方法,对移动边界腐蚀模型进行求解,并采用相应的人工腐蚀实验来对模型进行验证.计算结果表明,随着时间的推移,在固定的时间步长内移动界面的位移变缓,腐蚀深度随时间的延续而增加,符合腐蚀的变化规律.计算结果与实验数据有较好的吻合性,该模型可以用于混凝土在硫酸腐蚀下腐蚀速度的预测,指导实际的工程设计.

  4. DIRECTIONAL CONTROL BLASTING OF A 120 M REINFORCED CONCRETE CHIMNEY OF ANSHAN IRON AND STEEL COMPANY%鞍钢120m钢筋混凝土烟囱定向控制爆破

    Institute of Scientific and Technical Information of China (English)

    李桂臣; 王明林; 马群

    2000-01-01

    本文针对鞍钢120m高钢筋混凝土烟囱的结构特征和难以定向倾倒的狭窄场地条件,为确保烟囱爆破倾倒方向准确,倾倒过程安全、平稳,提出控制瞬时结构对称、合理选择爆破切口、圆心角等参数的对策.

  5. 高耸混凝土烟囱土-结构相互作用地震反应分析%Seismic response analysis of high-rise RC chimney including soil-structure interaction

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    目前在高耸混凝土烟囱结构抗震设计和抗震性能评估中,由于缺乏合适的计算模型,一般采川刚性地基假定而忽略土-结构相互作用效应,或者采用传统的集中参数模型而忽略土的非线性特性.针对此不足,本文选用 240 m高的钢筋混凝土烟囱作为研究对象,采用OpenSees程序,基于非线性文克尔地基梁模型和基于柔度法的分布塑性梁柱单元,建立了土体-基础-上部结构共同工作的整体非线性有限元分析模型,详细介绍了非线性文克尔地基梁模型主要参数的确定方法;研究了地基土非线性对高耸烟囱结构地震反应的影响,给出了考虑土-结构相互作用效应后结构周期、上部结构的内力和变形分布的变化规律.分析结果表明:考虑土-结构相互作用后,结构的自振特性、内力及节点位移都发生了不同程度的改变;考虑土体非线性特性的土-结构相互作用模型,峰值截面弯矩、剪力及截面曲率延性系数与不考虑土-结构相互作用时的结果之比分别介于0.921 ~1.219、0.732 ~1.29和0.822 ~1.536;而不考虑土体非线性特性的土-结构相互作用模型,峰值截面弯矩、剪力及截面曲率延性系数与不考虑土-结构相互作用时的结果之比分别介于0.838~1.578、0.92 ~ 1.76和0.656 ~2.831.不考虑土体非线性特性的土-结构相互作用模型的峰值截面弯矩、剪力及截面曲率延性系数的取值总体上较大,高估了烟囱结构在地震荷载作用下的内力需求.

  6. Origin of Pockmarks and Chimney Structures on the Flanks of the Storegga Slide,Offshore Norway%挪威近海Storegga滑坡侧翼麻点的成因及烟囱构造

    Institute of Scientific and Technical Information of China (English)

    Charles K; 王中梁

    2010-01-01

    @@ 1 Storegga滑坡崖地质背景 挪威的陆缘形态以Storegga滑坡崖为标志,该滑坡崖是由一系列巨大的全新世陡坡崩塌形成的.14C测年证实,最近一次崩塌出现在约7.2 ka以前.

  7. 30 CFR 816.72 - Disposal of excess spoil: Valley fills/head-of-hollow fills.

    Science.gov (United States)

    2010-07-01

    ..., 6-hour precipitation event. (b) Rock-core chimney drains. A rock-core chimney drain may be used in a... as the fill is not located in an area containing intermittent or perennial streams. A rock-core... upstream drainage is diverted around the fill. The alternative rock-core chimney drain system shall...

  8. Intra-field variability in microbial community associated with phase-separation-controlled hydrothermal fluid chemistry in the Mariner field, the southern Lau Basin

    Science.gov (United States)

    Takai, K.; Ishibashi, J.; Lupton, J.; Ueno, Y.; Nunoura, T.; Hirayama, H.; Horikoshi, K.; Suzuki, R.; Hamasaki, H.; Suzuki, Y.

    2006-12-01

    A newly discovered hydrothermal field called the Mariner field at the northernmost central Valu Fa Ridge (VFR) in the Lau Basin was explored and characterized by geochemical and microbiological surveys. The hydrothermal fluid (max. 365 u^C) emitting from the most vigorous vent site (Snow chimney) was boiling just beneath the seafloor at a water depth of 1908 m and two end-members of hydrothermal fluid were identified. Mineral and fluid chemistry of typical brine-rich (Snow chimney and Monk chimney) and vapor-rich (Crab Restaurant chimney) hydrothermal fluids and the host chimney structures were analyzed. Microbial community structures in three chimney structures were also investigated by culture-dependent and - independent analyses. The 16S rRNA gene clone analysis revealed that both bacterial and archaeal rRNA gene communities at the chimney surface zones were different among three chimneys. The bacterial and archaeal rRNA gene communities of the Snow chimney surface were very similar with those in the dead chimneys, suggesting concurrence of metal sulfide deposition at the inside and weathering at the surface potentially due to its large structure and size. Cultivation analysis demonstrated the significant variation in culturability of various microbial components, particularly of thermophilic H2- and/or S-oxidizing chemolithoautotrophs such as the genera Aquifex and Persephonella, among the chimney sites. The culturability of these chemolithoautotrophs might be associated with the input of gaseous energy and carbon sources like H2S, H2 and CH4 from the hydrothermal fluids, and might be affected by phase-separation- controlled fluid chemistry. In addition, inter-fields comparison of microbial community structures determined by cultivation analysis revealed novel characteristics of the microbial communities in the Mariner field of the Lau Basin among the global deep-sea hydrothermal systems.

  9. A Story of Tomorrow

    Institute of Scientific and Technical Information of China (English)

    DING ZHITAO

    2010-01-01

    @@ Chimneys were, for a short period of time, the symbols of industrialization and urbanization.They were soon reduced to symbols of pollution and backwardness. But today the site of a chimney at the World Expo's Urban Best Practices Area (UBPA) in Shanghai is still a place to marvel.

  10. 75 FR 22424 - Avalotis Corp.; Grant of a Permanent Variance

    Science.gov (United States)

    2010-04-28

    ... chimney construction to raise or lower workers in personnel cages, personnel platforms, and boatswain's... OSHA-approved State Plans covering private-sector employers that have identical standards and agree to.... Background In the past 36 years, a number of chimney construction companies demonstrated to OSHA that...

  11. 30 CFR 715.15 - Disposal of excess spoil.

    Science.gov (United States)

    2010-07-01

    ... underdrain or rock core; and (iv) Prevent formation of voids. (4) Surface water runoff from the area above... ridgeline. A rock-core chimney drain may be utilized instead of the subdrain and surface diversion system..., and which does not exceed 250,000 cubic yards may use the rock-core chimney drain. (2) The...

  12. Solar updraft tower - structural optimisation under dynamic wind action

    NARCIS (Netherlands)

    Van Eck, S.; Coenders, J.L.; Doomen, R.

    2015-01-01

    A solar updraft tower is a type of power plant which uses solar irradiation to generate electricity. It consists of three elements: a solar air collector, wind turbines and a chimney. The proposed concepts for this chimney schematise it as a 1-km-tall reinforced concrete shell, which are vulnerable

  13. Push-Pull Ventilation in a Painting Shop for Large Steel Constructions

    DEFF Research Database (Denmark)

    Svidt, Kjeld; Heiselberg, Per

    This paper describes the analysis of a push-pull ventilation system for a painting shop that is used for painting steel chimneys and windmill towers.......This paper describes the analysis of a push-pull ventilation system for a painting shop that is used for painting steel chimneys and windmill towers....

  14. SILICON AND OXYGEN ISOTOPIC COMPOSITION OF CHERTS FROM THE GACUN KUROKO-TYPE DEPOSIT, SICHUAN, AND COMPARISON WITH SILICA CHIMNEYS FROM THE MODERN SEAFLOOR%四川呷村黑矿型矿床硅质岩的硅、氧同位素组成及其与现代海底硅质烟囱比较研究

    Institute of Scientific and Technical Information of China (English)

    侯增谦; 吴世迎; T.Urabe

    1996-01-01

    本文首次报道了川西呷村黑矿型矿床硅质岩的硅、氧同位素组成,其δ18O为12.8‰-18.3‰,形成温度约99-120℃,δ30Si为0.0‰-1.5‰,与Mariana和Galapagos热液硅质烟囱的δ30Si值范围基本相当,揭示两者具相似的形成机制.硅质岩和硅质烟囱δ30Si最大值与相伴火山岩δ30Si值一致,反映硅质来自被热液淋滤交代的火山岩系.根据SiO2溶解度-温度关系提出,来自海底之下1-2km处的水-岩反应带、温度高于320℃的初始流体,通过绝热上升或传导冷凝,可在海底形成硫化物矿体,残余热液与海水大量混合及传导冷凝,可产生硅质岩和硅质烟囱.

  15. Ore-forming matter sources of hydrothermal black smoker chimneys in the Endeavour segment of the Juan de Fuca Ridge:sulfur isotope constraints%胡安·德富卡洋脊因代沃段热液黑烟囱体成矿物质来源:硫同位素的限制

    Institute of Scientific and Technical Information of China (English)

    姚会强; 周怀阳; 彭晓彤; 何高文

    2010-01-01

    选取胡安·德富卡洋脊(Juan de Fuca Ridge,JDFR)因代沃(Endeavour)段的17个热液黑烟囱体样品对其中的硫同位素进行分析测定,讨论了因代沃段热液活动区内黑烟囱体成矿的物质来源、将硫同位素数据与已发表的热液流体及硫化物数据耦合,并结合前人的成果得到如下认识:(1)因代沃段硫化物的硫同位素组成与其他无沉积物覆盖的洋脊硫化物硫同位素组成相似,然而其相比于南胡安·德富卡洋脊(South Juan de Fuca Ridge,SJFR)硫化物亏损重同位素;(2)结合前人研究成果,如果SJFR硫化物的硫全部来自基底玄武岩的淋洗与海水中的硫酸盐,那么因代沃段硫化物的硫可能有1%~3%来自沉积物的贡献,故提出因代沃段成矿系统中的硫来源主要来自基底玄武岩,同时伴随有少量海水硫酸盐来源及沉积物来源的硫加入;(3)将硫同位素数据与已发表的热液流体及硫化物数据进行耦合发现热液流体中的沉积物信号与硫化物中的硫可能来自不同的源,并提出沉积物端元可能位于下渗区.

  16. The hillsides would allow to produce electric power from renewable source; Les flancs de montagne pourraient permettre de produire de l'electricite d'origine renouvelable

    Energy Technology Data Exchange (ETDEWEB)

    Laby, F

    2006-09-15

    A solar tower is a renewable energy plant, designed to channel the air warmed by the sun, in order to produce electric power by the use of turbines. It is composed of a giant greenhouse with a chimney in its center. The capacity of this system is proportional to the chimney high. That is the reason why french engineers proposed to use the hillsides to build chimneys of many kilometers high. The project and some technical informations are provided in this paper. (A.L.B.)

  17. Oil heat venting technology and NFPA standard 31 revision year 2000

    Energy Technology Data Exchange (ETDEWEB)

    Krajewski, R.F. [Brookhaven National Labs., Upton, NY (United States)

    1997-09-01

    The revision of National Fire Protection Association (NFPA) Standard 31 for the year 2000 offers an opportunity to update the Appendix which currently offers recommendations for basic metal relining of masonry chimneys up to and including 25 feet. The paper discusses the proposed update of the existing recommendations to include flexible (rough) metal liners. In addition, the discussion addresses the inclusion of additional information for unlined (non-conforming), lined (conforming to NFPA 211) masonary chimneys, insulated metal chimneys, chimney heights beyond what are now published, as well as power venting both forced and induced draft. Included in the paper is a discussion of the existing Oil Heat Vent Analysis Program (OHVAP Version 3.0) and issues that need resolution to make it a better vent system model.

  18. Disease: H00021 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ium production Cadmium and cadmium compounds Chimney sweeping Radium-224 and its decay products Shale-oils Tobacco smoking... Secretan MB, Straif K. Tobacco smoking and cancer: a brief review of recent epidemiological evidence. Lung

  19. 1925 Clarkston Valley, USA Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Location: east of Helena. Affected area: 803,000 square kilometers. Damage: $0.3 million. Chimneys fell in every direction from the shaking. In addition, brick and...

  20. Safety for Older Consumers: Home Safety Checklist

    Science.gov (United States)

    ... away from curtains, furniture, blankets, and other combustibles. Ash trays, smoking materials, candles, hot plates, and other ... ll fuel-burning appliances, including furnaces, boilers, fireplaces, wood stoves, and water heaters, as well as chimneys, ...

  1. Application of grey model on analyzing the passive natural circulation residual heat removal system of HTR-10

    Institute of Scientific and Technical Information of China (English)

    ZHOU Tao; PENG Changhong; WANG Zenghui; WANG Ruosu

    2008-01-01

    Using the grey correlation analysis, it can be concluded that the reactor pressure vessel wall temperature has the strongest effect on the passive residual heat removal system in HTR (High Temperature gas-cooled Reactor),the chimney height takes the second place, and the influence of inlet air temperature of the chimney is the least. This conclusion is the same as that analyzed by the traditional method. According to the grey model theory, the GM(1,1) and GM(1, 3) model are built based on the inlet air temperature of chimney, pressure vessel temperature and the chimney height. Then the effect of three factors on the heat removal power is studied in this paper. The model plays an important role on data prediction, and is a new method for studying the heat removal power. The method can provide a new theoretical analysis to the passive residual heat removal system of HTR.

  2. Historie a současnost čištění komínů a kouřovodů

    OpenAIRE

    HÁLA, Pavel

    2015-01-01

    This work endeavours to map the development and actual level of chimney and flue cleaning in the Czech Republic including the appraisal of statutory instruments during the period from 1751 to 2015. The aim is to compare the techniques and methods of chimney cleaning used in the past as well as in the present and their effect on health and enviromental protection and safety. The work is divided into two parts. The theoretical one introduces historical changes of rules defining cleaning of chim...

  3. Variability in the microbial communities and hydrothermal fluid chemistry at the newly discovered Mariner hydrothermal field, southern Lau Basin

    Science.gov (United States)

    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.

  4. Effectiveness of various ventilation systems in reducing exposure to biomass related particles: A real-life experiment

    Directory of Open Access Journals (Sweden)

    Marek Majdan

    2015-01-01

    Full Text Available Background: Exposure to indoor air pollution, in particular particulate matter from biomass-fueled fires, has been identified as a major public health problem. Here, we test the effectiveness of simple ventilation systems in reducing concentrations of particulate matter in a standard experimental kitchen, built of traditional materials in Kenya. Materials and Methods: Continuous sampling for total particles, particulate matter <10 μm and <2.5 μm were sampled in a purpose-built rural kitchen using four ventilation scenarios: no ventilation, open window, open window and chimney and chimney only. The levels of pollutants were recorded and the effectiveness of different ventilation scenarios in reducing the exposure was compared. Results: For each size of particle, any type of ventilation showed a decrease in concentrations (P < 0.001, compared to the unventilated scenario of 70% or more. The lowest concentrations were observed when only a chimney was used; opening a window did not significantly alter the effectiveness of the chimney. Additionally, the changes in pollutant levels over time showed the least variation and lowest mean values when a chimney only was used. Conclusions: Simple ventilation systems, especially installation of a chimney, proved to be effective in significantly decreasing the exposure to biomass fuel-related indoor particulate matter exposure. The application of such technology may help in tackling this important public health issue.

  5. Newly discovered hydrothermal system on the Alarcón Rise, Mexico

    Science.gov (United States)

    Paduan, J. B.; Clague, D. A.; Caress, D. W.; Lundsten, L.; Martin, J. F.; Nieves-Cardoso, C.

    2012-12-01

    The Alarcón Rise lies at the mouth of the Gulf of California, and is the last segment of the East Pacific Rise before the plate boundary redirects into the gulf. As part of MBARI's expedition to the gulf in 2012, the neovolcanic zone of the entire ridge segment was mapped by MBARI's mapping AUV. 110 potential hydrothermal chimneys were identified in the new high resolution maps, and 70 were visited with the ROV Doc Ricketts, after having been sought in vain without the maps on an expedition in 2003. Two active vent fields were found, and have been named Meyibó and Ja sít from local native languages. They lie 2.5km apart at ~2300m depth, and are associated with a large, young sheet flow 1/3 of the way along the ridge from the south, on the most inflated part of the ridge. The southern field, Meyibó, contains 14 active chimneys (confirmed with ROV observations) nestled in grabens of several highly fractured cones surrounded by the sheet flow, and generally aligned with its discontinuous, 8km-long fissure system. The northern field, Ja sít, is a broad cluster of 8 active chimneys (also confirmed) rising above the sheet flow's channel system, more than 150m from the fissure. The chimneys stand as tall as 18 m. The most vigorous vent "black smoke" (mineral-rich fluid) >300°C and others are bathed in "white smoke". The active chimneys are populated with bacterial mat and dense clumps of Riftia pachyptila with tubes as long as 1.5m. Abundant limpets, Bythograea thermydron and galatheid crabs, and the pink vent fish Thermarces cerberus were on and near the giant tube worms. Alvinellid worms were observed at 2 chimneys. Some cracks in nearby lava flows vented clear fluid and were populated with tubeworms or Calyptogena magnifica clams. Several chimneys exhibited signs of waning activity: dead tubeworms were still attached and only a minor portion of the edifice supported bacterial mat and live tubeworms. Inactive chimneys are more numerous (48 were confirmed with ROV

  6. Numerical modeling of boiling heat transfer in porous media

    International Nuclear Information System (INIS)

    Theoretical models were developed and validated to investigate boiling heat transfer in porous layers with and without the presence of chimneys. The critical heat flux and distributions of temperature, liquid saturation, liquid and vapor pressures, and liquid and vapor velocities were predicted numerically under typical PWR conditions. The results indicate that a porous layer produces a higher heat transfer coefficient in the nucleate boiling regime, as is well-known, and could potentially yield a much higher critical heat flux than a plain surface does. Moreover, a chimney-type porous layer can have a better thermal performance, i.e., heat transfer coefficient and critical heat flux than a homogeneous one, primarily due to the presence of chimneys providing pathways for vapor to escape from the porous layer with less resistance

  7. Natural outlet of flue gases

    Science.gov (United States)

    Adámek, Karel; Kolář, Jan; Peukert, Pavel

    2016-06-01

    Many incidents of poisoning all the time became due to bad natural exhaust of burnt product from heating devices. The aim of this article is to simulate some reasons of it, therefore the content is focused on some influences, only - the vertical and horizontal shape of the outlet channel, the design of the chimney cap, situation of the surrounding walls, combined with the wind influence etc. It does not solve the possible bad maintaining of both chimney and device, bad supply of the combustion air etc. As main results of simulation there is presented an optimum cap shape of the chimney and an unsuitable influence of the unsteady starting of the flow just after the burner ignition.

  8. Resistance factors, two phase multipliers and void fractions for best estimate flow calculations in Dodewaard fuel bundles

    International Nuclear Information System (INIS)

    Values are given for resistance factors, two phase multipliers and core and chimney void fractions in the fuel and chimney to be used in best estimate calculations of the flow in Dodewaard fuel bundles. The resistance factors are based on single phase experimental data for a mockup of the Dodewaard fuel bundle. The two phase multipliers are determined from two phase measurements of mockups of other fuel bundles for nuclear reactors. This is also true for the in bundle void fractions. The void fractions in the chimney have been validated by measured void fractions in large diameter pipes. The recommended changes to the existing input for calculations are somewhat larger than the uncertainties in the measurements. (author). 37 refs.; 48 figs.; 4 tabs

  9. Wood burning stoves and small boilers - particle emissions and reduction initiatives; Braendeovne og smae kedler - partikelemissioner og reduktionstiltag

    Energy Technology Data Exchange (ETDEWEB)

    Illerup, J.B.; Capral Henriksen, T.; Lundhede, T. [Danmarks Miljoeundersoegelser, Aarhus Universitet, Aarhus (Denmark); Breugel, C. van; Zoellner Jensen, N. [Miljoestyrelsen, Copenhagen (Denmark)

    2007-06-15

    Pollution from burning wood in private households, and the environmental and health consequences of this is determined in practice by a complicated interaction between a number of factors, including firing habits, fuel, type of stove/boiler, chimney and location of the chimney in relation to the surroundings. This report maps out the technologies used today for burning wood in private households, how these technologies contribute to particle emissions and which technologies may potentially reduce emissions of particles from burning wood in households in Denmark. Moreover, the possible emissions reductions and the financial costs incurred by consumers from different initiatives have been estimated. This report does not deal with possible initiatives for improvement of firing habits, fuel quality and chimneys. (au)

  10. Chemical vapor deposition reactor. [providing uniform film thickness

    Science.gov (United States)

    Chern, S. S.; Maserjian, J. (Inventor)

    1977-01-01

    An improved chemical vapor deposition reactor is characterized by a vapor deposition chamber configured to substantially eliminate non-uniformities in films deposited on substrates by control of gas flow and removing gas phase reaction materials from the chamber. Uniformity in the thickness of films is produced by having reactive gases injected through multiple jets which are placed at uniformally distributed locations. Gas phase reaction materials are removed through an exhaust chimney which is positioned above the centrally located, heated pad or platform on which substrates are placed. A baffle is situated above the heated platform below the mouth of the chimney to prevent downdraft dispersion and scattering of gas phase reactant materials.

  11. Faster than "g", Revisited with High-Speed Imaging

    Science.gov (United States)

    Vollmer, Michael; Mollmann, Klaus-Peter

    2012-01-01

    The introduction of modern high-speed cameras in physics teaching provides a tool not only for easy visualization, but also for quantitative analysis of many simple though fast occurring phenomena. As an example, we present a very well-known demonstration experiment--sometimes also discussed in the context of falling chimneys--which is commonly…

  12. Highly turbulent Taylor-Couette flow: direct numerical simulations

    NARCIS (Netherlands)

    Ostilla Monico, Rodolfo

    2015-01-01

    Turbulence is all around us. Even if we are familiar with every day instances of turbulence, like the smoke coming out of a chimney, it remains a not-well-understood phenomenum. As it is impossible to fully simulate turbulence to precisely take into account its effect, models must be used. These rel

  13. 国外暖通空调实用文献摘要选编

    Institute of Scientific and Technical Information of China (English)

    秦慧敏

    2009-01-01

    泰国利用屋顶太阳能烟囱效应的冷却吊顶实验和数据解析[a①],Utilization of cool ceiling with roof solar chimney in Thailand: The experimental and numerical analysis. Renew Energy(英国)34[1]623-633(2009);

  14. Rapid growth of mineral deposits at artificial seafloor hydrothermal vents.

    Science.gov (United States)

    Nozaki, Tatsuo; Ishibashi, Jun-Ichiro; Shimada, Kazuhiko; Nagase, Toshiro; Takaya, Yutaro; Kato, Yasuhiro; Kawagucci, Shinsuke; Watsuji, Tomoo; Shibuya, Takazo; Yamada, Ryoichi; Saruhashi, Tomokazu; Kyo, Masanori; Takai, Ken

    2016-01-01

    Seafloor massive sulphide deposits are potential resources for base and precious metals (Cu-Pb-Zn ± Ag ± Au), but difficulties in estimating precise reserves and assessing environmental impacts hinder exploration and commercial mining. Here, we report petrological and geochemical properties of sulphide chimneys less than 2 years old that formed where scientific boreholes vented hydrothermal fluids in the Iheya-North field, Okinawa Trough, in East China Sea. One of these infant chimneys, dominated by Cu-Pb-Zn-rich sulphide minerals, grew a height of 15 m within 25 months. Portions of infant chimneys are dominated by sulphate minerals. Some infant chimneys are sulphide-rich similar to high-grade Cu-Pb-Zn bodies on land, albeit with relatively low As and Sb concentrations. The high growth rate reaching the 15 m height within 25 months is attributed to the large hydrothermal vent more than 50 cm in diameter created by the borehole, which induced slow mixing with the ambient seawater and enhanced efficiency of sulphide deposition. These observations suggest the possibility of cultivating seafloor sulphide deposits and even controlling their growth and grades through manipulations of how to mix and quench hydrothermal fluids with the ambient seawater. PMID:26911272

  15. Microbial diversity of Loki's Castle black smokers at the Arctic Mid-Ocean Ridge.

    Science.gov (United States)

    Jaeschke, A; Jørgensen, S L; Bernasconi, S M; Pedersen, R B; Thorseth, I H; Früh-Green, G L

    2012-11-01

    Hydrothermal vent systems harbor rich microbial communities ranging from aerobic mesophiles to anaerobic hyperthermophiles. Among these, members of the archaeal domain are prevalent in microbial communities in the most extreme environments, partly because of their temperature-resistant and robust membrane lipids. In this study, we use geochemical and molecular microbiological methods to investigate the microbial diversity in black smoker chimneys from the newly discovered Loki's Castle hydrothermal vent field on the Arctic Mid-Ocean Ridge (AMOR) with vent fluid temperatures of 310-320 °C and pH of 5.5. Archaeal glycerol dialkyl glycerol tetraether lipids (GDGTs) and H-shaped GDGTs with 0-4 cyclopentane moieties were dominant in all sulfide samples and are most likely derived from both (hyper)thermophilic Euryarchaeota and Crenarchaeota. Crenarchaeol has been detected in low abundances in samples derived from the chimney exterior indicating the presence of Thaumarchaeota at lower ambient temperatures. Aquificales and members of the Epsilonproteobacteria were the dominant bacterial groups detected. Our observations based on the analysis of 16S rRNA genes and biomarker lipid analysis provide insight into microbial communities thriving within the porous sulfide structures of active and inactive deep-sea hydrothermal vents. Microbial cycling of sulfur, hydrogen, and methane by archaea in the chimney interior and bacteria in the chimney exterior may be the prevailing biogeochemical processes in this system.

  16. First Insights into the Genome of the Moderately Thermophilic Bacterium Clostridium tepidiprofundi SG 508T.

    Science.gov (United States)

    Poehlein, Anja; Friedrich, Ines; Krüger, Larissa; Daniel, Rolf

    2016-01-01

    The moderately thermophilic bacterium Clostridium tepidiprofundi is Gram-positive and belongs to clostridial cluster I. It was isolated from a hydrothermal vent chimney. Substrates utilized by C. tepidiprofundi include casein, peptone, tryptone, yeast extract, beef extract, starch, maltose, and glucose. The genome consists of one replicon (3.06 Mb). PMID:27174286

  17. First Insights into the Genome of the Moderately Thermophilic Bacterium Clostridium tepidiprofundi SG 508T

    OpenAIRE

    Poehlein, Anja; Friedrich, Ines; Krüger, Larissa; Daniel, Rolf

    2016-01-01

    The moderately thermophilic bacterium Clostridium tepidiprofundi is Gram-positive and belongs to clostridial cluster I. It was isolated from a hydrothermal vent chimney. Substrates utilized by C. tepidiprofundi include casein, peptone, tryptone, yeast extract, beef extract, starch, maltose, and glucose. The genome consists of one replicon (3.06 Mb).

  18. Bio-technologies; Biotechnologies

    Energy Technology Data Exchange (ETDEWEB)

    Grawitz, X. [Systemes Bio-Industries, 92 - Boulogne Billancourt (France)

    1997-12-31

    The impact of the French 2910 decree concerning pollution emission (emission levels of boilers, turbines, engines and dryers) on the calculation of chimney stack height, gas ejection minimum speed and influence of obstacles, is reviewed. The energy efficiency improvement of 400 kW to 50 MW boilers and the implementation of a cogeneration plant are also described

  19. 29 CFR 1926.57 - Ventilation.

    Science.gov (United States)

    2010-07-01

    ... downdraft booths are provided with doors, such doors shall be closed when spray painting. (7) Make-up air. (i) Clean fresh air, free of contamination from adjacent industrial exhaust systems, chimneys, stacks... exhaust ventilation when used as described in (a) shall be designed to prevent dispersion into the air...

  20. Microbial Diversity Associated with High Temperature Sulfide Deposits Along the East Pacific Rise Deep-Sea Hydrothermal Vents

    Science.gov (United States)

    Brooks, D.; Hoek, J.; Banta, A. B.; von Damm, K.; Reysenbach, A.

    2002-12-01

    In January 2002, hydrothermal chimneys were collected using DSV Alvin from active vents from 9° 17N to 9° 50N and 20° 49N to 20° 50N. Hydrothermal fluids were collected for end member chemistry prior to collecting the sulfide deposits. Chimney samples were sub-sectioned, separating surface and associated biofilm samples from inner chimney samples. Microbial diversity of sub-samples was assessed using culture-dependent and culturing-independent small subunit (16S) ribosomal RNA-based techniques. Initial bacterial diversity assessments using denaturing gradient gel electrophoresis (DGGE) support the global prevalence of epsilon Proteobacteria associated with deep-sea sulfide structures. These are closely related to the sulfur-reducing isolate Nautilia lithotrophica. The biofilm communities varied in complexity with one sample containing several 16S rRNA sequences (phylotypes, OTU's) of alpha, epsilon, and gamma Proteobacteria while others contained a single phylotype of epsilon Proteobacteria. One proteobacterial phylotype was present in all but one of the surface samples, and this sample contained unique alpha and epsilon proteobacterial sequences. The inner chimney samples lacked the most common epsilon proteobacterial 16S rRNA sequences. Enrichment culturing was restricted to selecting for thermophilic chemolithoautotrophic hydrogen-oxidizing Bacteria. The widespread distribution of Persephonella spp. was confirmed, and novel enrichments of a sheathed and as yet unidentified chemolithotroph were obtained.

  1. 78 FR 60900 - Kiewit Power Constructors Co. et al. (Avalotis Corp., Bowen Engineering Corporation, Commonwealth...

    Science.gov (United States)

    2013-10-02

    ... Occupational Safety and Health Administration Kiewit Power Constructors Co. et al. (Avalotis Corp., Bowen... Kiewit Power Constructors Co. (Kiewit; see 72 FR 6002). This publication included an interim order that..., Inc., NAES Power Contractors, Pullman Power, LLC, R and P Industrial Chimney Co., Inc., T. E....

  2. Passive solar systems (solar architecture research and development in Italy). Solare passivo: sottoprogetto energia solare, eolica ed idraulica

    Energy Technology Data Exchange (ETDEWEB)

    1989-02-01

    This collection of papers on solar achitecture research and development deals with test facilities now available in Italy for performance testing/data acquisition relative to passive solar system components (i.e.Trombe walls) and provides an update on the developments by various consultants of marketable products (solar water heaters, solar chimneys, sunlight dousers, etc).

  3. Detection of active hydrothermal vent fields in the Pescadero Basin and on the Alarcon Rise using AUV multibeam and CTD data

    Science.gov (United States)

    Caress, D. W.; Troni, G.; Clague, D. A.; Paduan, J. B.; Martin, J. F.; Thomas, H. J.; Thompson, D.; Conlin, D.; Martin, E. J.; meneses-Quiroz, E.; Nieves-Cardoso, C.; Angel Santa Rosa del Rio, M.

    2015-12-01

    The MBARI AUV D. Allan B. collected high resolution bathymetry, sidescan, and subbottom profiles along the neovolcanic zone of the Alarcon Rise and across the southern Pescadero Basin during 2012 and 2015 MBARI expeditions to the Gulf of California (GOC). The combination of high resolution multibeam bathymetry and seawater temperature data has proven effective in identifying active high temperature vent fields, as validated by inspection and sampling during ROV dives. The AUV carries a 200 kHz multibeam sonar, 110 kHz chirp sidescan sonar, a 1-6 kHz chirp subbottom profiler, and a conductivity, temperature and depth (CTD) sensor for ~17-hour duration missions. Flying at 5.4 km/hr at 50 m altitude, the processed AUV bathymetry has a 0.1 m vertical precision and a 1 m lateral resolution. Chimneys taller than 1.5 m are sufficiently distinctive to allow provisional identification. The CTD temperature data have a nominal 0.002°C accuracy. Following calculation of potential temperature and correcting for average local variation of potential temperature with depth, anomalies greater than 0.05 °C can be reliably identified using a spike detection filter. MBARI AUV mapping surveys are typically planned using a 150 m survey line spacing, so the CTD data may be collected as much as 75 m away from any vent plume source. Five active high temperature vent fields were discovered in the southern GOC, with the Auka Field in the southern Pescadero Basin, and the Ja Sít, Pericú, Meyibó, and Tzab-ek Fields along the Alarcon Rise. In all five cases, hydrothermal vent chimneys are readily identifiable in the multibeam bathymetry, and temperature anomalies are observed above background variability. Other apparent hydrothermal chimneys were observed in the bathmetry that did not exhibit water temperature anomalies; most of these were visited during ROV dives and confirmed to be inactive sites. The maximum water column anomalies are 0.13°C observed above the Meyibó field and 0.25

  4. On the use of nuclear explosives for stimulation of geothermal heat

    International Nuclear Information System (INIS)

    Many areas of the world exist where high temperature isotherms supported by heat flow from the core of the earth occur very close to the surface of the earth. Commercial exploitation of these sources of energy has only recently become practical and is limited to those areas where a natural system of fracture acts to collect heat from a large volume of rock and sufficient natural water is available to act as a heat transfer agent. Recent studies have indicated many more areas of geothermal heat are available than had been identified previously. The nuclear application envisages the creation of a chimney and associated fracture system with a nuclear explosion, introduction of water into the chimney-fracture system, and removal of superheated steam for the generation of electrical power. Three phenomena are considered: utilization of the heat content of the rock in the chimney and fracture zone; heat flow from the surrounding medium to the fracture zone or chimney by conductivity; and interconnection of a preexisting network of fracture by the highly permeable chimney and fracture zone. A 1-Mt example is examined showing that over 109 kWh are available in the chimney, and over 1010 kWh in the central portion of the fracture zone. Using the current commercial value of 2 mills/kWh for such steam, the above heat has a worth of over S30,000,000. In addition, heat flow into the fracture zone would represent over $1 million per year additional value. Interconnection of fractures drawing heat from far removed volumes would be very site-dependent and difficult to estimate, and have not been included. Use of an array would permit circulation between chimneys with the resultant utilization of the heat energy contained in the intervening volume. Ground shock associated with such an application would probably require development of a 30 to 50 year supply before the power plant is constructed. Radiological safety problems would be confined to operation of the power plant. (author)

  5. Strontium isotopes and rare-earth element geochemistry of hydrothermal carbonate deposits from Lake Tanganyika, East Africa

    Energy Technology Data Exchange (ETDEWEB)

    Barrat, J.A.; Boulegue, J.; Tiercelin, J.J.; Lesourd, M.

    2000-01-01

    At Cape Banza (North Tanganyika Lake), fluids and aragonite chimneys have been collected many times since the discovery of this sublacustrine field in 1987. This sampling has been investigated here for the Sr isotopic compositions and the rare-earth element features of the carbonates and a few fluid samples. The {sup 87}Sr/{sup 86}Sr ratios of the chimneys indicate that they have precipitated from a mixture of lake water (more than 95%) and hydrothermal fluids. No zoning in the chimneys was detected with the Sr data. For the rare-earth elements, the situation is more complex. The external walls of the chimneys are rare-earth-element-poor (La {approx} 500 ppb, Yb {approx} 200 ppb, La/Yb = 2 to 3.4). Their shale normalized rare-earth element patterns suggest that they are in equilibrium with the inferred carbonate-depositing fluids. The rare-earth element concentrations of the internal walls of the chimneys are significantly light rare earth elements (LREE)-enriched with La contents sometimes up to 5 ppm. The authors suggest that they contain more vent-fluid rare-earth elements than the external wall samples, possibly adsorbed on the surface of growing crystals or simply hosted by impurities. It was not possible to constrain the nature of these phases, but the variations of the compositions of the internal wall materials of the active chimneys with time, as well as data obtained on an inactive chimney indicate that this rare-earth element excess is mobile. Partition coefficients were calculated between the external wall aragonite and carbonate-depositing fluid. The results are strikingly similar to the values obtained by Sholkovitz and Shen (1995) on coral aragonite, and suggest that there is no significant biologic effect on the incorporation of rare-earth elements into coral aragonite and that the various carbonate complexes involved Me(CO{sub 3}{sup +}) complexes are the main LREE carriers in seawater instead of Me(CO{sub 3}){sub 2}{sup {minus}} in Banza fluids

  6. Regional Mapping and Resource Assessment of Shallow Gas Hydrates of Japan Sea - METI Launched 3 Years Project in 2013.

    Science.gov (United States)

    Matsumoto, R.

    2014-12-01

    Agency of Natural Resources and Energy of METI launched a 3 years shallow gas hydrate exploration project in 2013 to make a precise resource assessment of shallow gas hydrates in the eastern margin of Japan Sea and around Hokkaido. Shallow gas hydrates of Japan Sea occur in fine-grained muddy sediments of shallow subsurface of mounds and gas chimneys in the form of massive nodular to platy accumulation. Gas hydrate bearing mounds are often associated with active methane seeps, bacterial mats and carbonate concretions and pavements. Gases of gas hydrates are derived either from deep thermogenic, shallow microbial or from the mixed gases, contrasting with totally microbial deep-seated stratigraphically controlled hydrates. Shallow gas hydrates in Japan Sea have not been considered as energy resource due to its limited distribution in narrow Joetsu basin. However recently academic research surveys have demonstrated regional distribution of gas chimney and hydrate mound in a number of sedimentary basins along the eastern margin of Japan Sea. Regional mapping of gas chimney and hydrate mound by means of MBES and SBP surveys have confirmed that more than 200 gas chimneys exist in 100 km x 100 km area. ROV dives have identified dense accumulation of hydrates on the wall of half collapsed hydrate mound down to 30 mbsf. Sequential LWD and shallow coring campaign in the Summer of 2014, R/V Hakurei, which is equipped with Fugro Seacore R140 drilling rig, drilled through hydrate mounds and gas chimneys down to the BGHS (base of gas hydrate stability) level and successfully recovered massive gas hydrates bearing sediments from several horizons.

  7. Investigation of hydrogen recombination under natural convection conditions; Untersuchungen zur Wasserstoffrekombination unter Naturkonvektionsbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Berno

    2015-09-04

    Passive Autocatalytic Recombiners (PAR) are installed inside the containment of nuclear power plants in order to prevent the build-up of flammable mixtures and to mitigate the effects of hydrogen deflagrations, which can occur in the event of a severe accident combined with the release of hydrogen. In order to simulate the operating behaviour of PARs, the computer program REKO-DIREKT is being developed at the Forschungszentrum Juelich in collaboration with the Institute for Reactor Safety and Reactor Technology at the RWTH Aachen. For the validation of the code, data from experimental facilities operated at Juelich are used. This work focusses on the analysis of the chimney effect through the PAR housing as well as the optimization of the chimney model of REKO-DIREKT. Therefore experimental investigations are carried out in the REKO-4 facility under natural convection conditions. This facility is equipped with numerous measuring devices, e.g. katharometers for in-situ measuring of the hydrogen concentration and the optical flow measurement technique Particle-Image-Velocimetry. In preliminary assessments the equipment is being qualified in order to determine the measurement accuracy. In the following experimental investigations, a small-scale PAR is used, that is built in a modular way allowing it to be equipped with different chimney geometries. The experimental results produce a database that shows the central correlation between the hydrogen concentration, the catalyst temperature and the inlet velocity. The results include the variation of the recombiner's chimney height and experiments at different operating pressures. After optimization of the chimney model, the simulation program is validated against experiments in the large-scale facility THAI in Eschborn, which have been performed subsequent to this thesis in the context of the OECD/NEA-THAI project. Finally, the influence of a downward-directed, near-wall flow on the operational behaviour of the small

  8. Investigation of hydrogen recombination under natural convection conditions

    International Nuclear Information System (INIS)

    Passive Autocatalytic Recombiners (PAR) are installed inside the containment of nuclear power plants in order to prevent the build-up of flammable mixtures and to mitigate the effects of hydrogen deflagrations, which can occur in the event of a severe accident combined with the release of hydrogen. In order to simulate the operating behaviour of PARs, the computer program REKO-DIREKT is being developed at the Forschungszentrum Juelich in collaboration with the Institute for Reactor Safety and Reactor Technology at the RWTH Aachen. For the validation of the code, data from experimental facilities operated at Juelich are used. This work focusses on the analysis of the chimney effect through the PAR housing as well as the optimization of the chimney model of REKO-DIREKT. Therefore experimental investigations are carried out in the REKO-4 facility under natural convection conditions. This facility is equipped with numerous measuring devices, e.g. katharometers for in-situ measuring of the hydrogen concentration and the optical flow measurement technique Particle-Image-Velocimetry. In preliminary assessments the equipment is being qualified in order to determine the measurement accuracy. In the following experimental investigations, a small-scale PAR is used, that is built in a modular way allowing it to be equipped with different chimney geometries. The experimental results produce a database that shows the central correlation between the hydrogen concentration, the catalyst temperature and the inlet velocity. The results include the variation of the recombiner's chimney height and experiments at different operating pressures. After optimization of the chimney model, the simulation program is validated against experiments in the large-scale facility THAI in Eschborn, which have been performed subsequent to this thesis in the context of the OECD/NEA-THAI project. Finally, the influence of a downward-directed, near-wall flow on the operational behaviour of the small

  9. Focused fluid flow in the Baiyun Sag, northern South China Sea: implications for the source of gas in hydrate reservoirs

    Institute of Scientific and Technical Information of China (English)

    CHEN Duanxin; WU Shiguo; DONG Dongdong; MI Lijun; FU Shaoying; SHI Hesheng

    2013-01-01

    The origin and migration of natural gas and the accumulation of gas hydrates within the Pearl River Mouth Basin of the northern South China Sea are poorly understood.Based on high-resolution 2D/3D seismic data,three environments of focused fluid flow:gas chinmeys,mud diapirs and active faults have been identified.Widespread gas chimneys that act as important conduits for fluid flow are located below bottom simulating reflections and above basal uplifts.The occurrence and evolution of gas chimneys can be divided into a violent eruptive stage and a quiet seepage stage.For most gas chimneys,the strong eruptions are deduced to have happened during the Dongsha Movement in the latest Miocene,which are observed below Pliocene strata and few active faults develop above the top of the Miocene.The formation pressures of the Baiyun Sag currently are considered to be normal,based on these terms:1) Borehole pressure tests with pressure coefficients of 1.043-1.047; 2) The distribution of gas chimneys is limited to strata older than the Pliocene; 3) Disseminated methane hydrates,rather than fractured hydrates,are found in the hydrate samples; 4) The gas hydrate is mainly charged with biogenic gas rather than thermogenic gas based on the chemical tests from gas hydrates cores.However,periods of quiet focused fluid flow also enable the establishment of good conduits for the migration of abundant biogenic gas and lesser volumes of thermogenic gas.A geological model governing fluid flow has been proposed to interpret the release of overpressure,the migration of fluids and the formation of gas hydrates,in an integrated manner.This model suggests that gas chimneys positioned above basal uplifts were caused by the Dongsha Movement at about 5.5 Ma.Biogenic gas occupies the strata above the base of the middle Miocene and migrates slowly into the gas chimney columns.Some of the biogenic gas and small volumes of thermogenic gas eventually contribute to the formation of the gas

  10. Remote measurements of the dimensions for reactor structure in HANARO

    International Nuclear Information System (INIS)

    The HANARO, an open-tank-in-pool type research reactor of 30 MWt power in Korea, has been operating for 10 years since its initial criticality in February 1995. The reactor power has been gradually increased to the full power reached in June 2004. This paper describes a few mechanical technologies for the remote measurements of the dimensions of the reactor main components for the installation of new facilities and for the in-service inspections. After a few years operation, a new bracket called 'in-chimney bracket' was required in the Hanaro chimney to support the irradiation facilities in the core against the seismic and flow-induced vibrations. The inner dimensions of the chimney walls and four opening holes on the wall were required to be measured for the design and installation of the in-chimney bracket because there were not enough as-built dimensions. Therefore we remotely measured the as-installed dimensions of the chimney with a technology of relative measurement method and special tools using a remote caliper mechanism. We verified the validity of the measured data by the successful installation and service of the in-chimney bracket. The other technology was required to measure very accurate dimensions of a vertical hole of Φ160 mm in the reflector vessel for the installation of a cold neutron source with a minimum light water film in the warped tube due to welding deformation. A dial gauge moving on two linear motion guides assembled on a strong axis was used to measure the diameter, eccentricity and straightness. The measured dimensions were verified to be accurate enough to apply in the design of the vacuum tube which will be installed in the hole. The inner shell of the reflector vessel surrounding the core is the most critical part from the viewpoint of neutron irradiation. The periodic measurement of the dimensional change in the vertical straightness of the inner shell is considered as one of the in-service inspections to confirm the analysis

  11. Deposition of Biogenic Iron Minerals in a Methane Oxidizing Microbial Mat

    Directory of Open Access Journals (Sweden)

    Christoph Wrede

    2013-01-01

    Full Text Available The syntrophic community between anaerobic methanotrophic archaea and sulfate reducing bacteria forms thick, black layers within multi-layered microbial mats in chimney-like carbonate concretions of methane seeps located in the Black Sea Crimean shelf. The microbial consortium conducts anaerobic oxidation of methane, which leads to the formation of mainly two biomineral by-products, calcium carbonates and iron sulfides, building up these chimneys. Iron sulfides are generated by the microbial reduction of oxidized sulfur compounds in the microbial mats. Here we show that sulfate reducing bacteria deposit biogenic iron sulfides extra- and intracellularly, the latter in magnetosome-like chains. These chains appear to be stable after cell lysis and tend to attach to cell debris within the microbial mat. The particles may be important nuclei for larger iron sulfide mineral aggregates.

  12. Drilling successful from ROV Ventana

    Science.gov (United States)

    Stakes, Debra S.; McFarlane, James A. R.; Holloway, G. Leon; Greene, H. Gary

    Cores of granite and deformed sediment from the walls of Monterey Canyon were successfully recovered from December 30 to 31, 1992, by Monterey Bay Aquarium Research Institute's (MBARI) Remotely Operated Vehicle (ROV) Ventana using a small-diameter, double-barrel drill with a diamond bit. This HSTR (Holloway-Stakes-Tengdin-Rajcula) drill was developed to drill cores horizontally from sulfide/sulfate walls of active black smokers. The drill was first successfully used by the submersible Alvin in October 1991 to drill into massive sulfide chimneys, on the Juan de Fuca Ridge (Eos, June 30, 1992, p. 273), and it was subsequently used with equal success on the chalcopyrite-rich chimneys from 21°N and 9°N on the East Pacific Rise. The recent December dives, however, marked the first time that drilling has ever been attempted from the smaller ROV and the first time coring into the harder igneous rock substrate has been attempted.

  13. Solar ventilation and tempering

    Science.gov (United States)

    Adámek, Karel; Pavlů, Miloš; Bandouch, Milan

    2014-08-01

    The paper presents basic information about solar panels, designed, realized and used for solar ventilation of rooms. Used method of numerical flow simulation gives good overview about warming and flowing of the air in several kinds of realized panels (window, facade, chimney). Yearlong measurements give a good base for calculations of economic return of invested capital. The operation of the system in transient period (spring, autumn) prolongs the period without classical heating of the room or building, in winter the classical heating is supported. In the summer period the system, furnished with chimney, can exhaust inner warm air together with necessary cooling of the system by gravity circulation, only. System needs not any invoiced energy source; it is supplied entirely by solar energy. Large building systems are supported by classical electric fan respectively.

  14. Diversity of microbial communities of Loki's Castle black smoker field at the ultra-slow spreading Arctic Mid-Ocean Ridge

    Science.gov (United States)

    Jaeschke, A.; Bernasconi, S. M.; Thorseth, I. H.; Pedersen, R.; Früh-Green, G.

    2010-12-01

    Here we present an organic geochemical study of Loki’s Castle, a black smoker field recently discovered at the Arctic Mid-Ocean Ridge (AMOR) in the Norwegian-Greenland Sea at around 73.2°N. Located at the Mohn-Knipovich Ridge, which is one of the slowest spreading ridge segments on Earth, Loki’s Castle is the most northerly major hydrothermal vent field known to date. The vent field is composed of five actively venting (320°C) black-smoker chimneys that tower on top of a large mound of hydrothermal sulfide deposits. Loki’s Castle is a basalt-hosted hydrothermal system, but high methane and ammonium contents in the vent fluids strongly indicate a sedimentary component below the volcanic ridge. In 2009, another site of low-temperature hydrothermal venting hosting numerous barite chimneys was discovered in the vicinity of the black smokers, which probably results from subsurface mixing of diffuse hydrothermal fluid with seawater. In our study, variations in microbial communities associated with the formation of actively venting, sulfide and sulfate chimneys in this essentially unexplored ultraslow spreading ridge system are assessed based on biomarker lipid and compound-specific carbon isotope analyses. Lipid extracts from an active, high-temperature sulfide chimney yielded abundant archaeal di- and tetraether lipids as well as irregular isoprenoidal hydrocarbons (PMIs) that are associated with archaeal methanogens and methanotrophs. Predominant archaeal biomarker lipids include archaeol, sn-2-hydroxyarchaeol as well as glycerol dialkyl glycerol tetraethers (GDGTs) containing 0-4 cyclopentyl moieties. In addition, GDGTs with an additional covalent bond between the isoprenoid hydrocarbon chains, so-called H-shaped GDGTs, containing 0-4 cyclopentyl rings were also found to be abundant components and are indicative of hyperthermophilic methanogens. Biomarkers characteristic of eukaryotes (sterols) and bacteria (fatty acids and hopanoids) were less prevalent in

  15. Differential effects of smoking on lung cancer mortality before and after household stove improvement in Xuanwei, China

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K.M.; Chapman, R.S.; Shen, M.; Lubin, J.H.; Silverman, D.T.; He, X.; Hosgood, H.D.; Chen, B.E.; Rajaraman, P.; Caporaso, N.E.; Fraumeni, J.F.; Blair, A.; Lan, Q. [NCI, Bethesda, MD (USA)

    2010-08-24

    In Xuanwei County, Yunnan Province, China, lung cancer mortality rates in both males and females are among the highest in China. We evaluated differential effects of smoking on lung cancer mortality before and after household stove improvement with chimney to reduce exposure to smoky coal emissions in the unique cohort in Xuanwei, China. Effects of independent variables on lung cancer mortality were measured as hazard ratios and 95% confidence intervals using a multivariable Cox regression model that included separate time-dependent variables for smoking duration (years) before and after stove improvement. We found that the effect of smoking on lung cancer risk becomes considerably stronger after chimney installation and consequent reduction of indoor coal smoke exposure.

  16. Differential effects of smoking on lung cancer mortality before and after household stove improvement in Xuanwei, China

    Science.gov (United States)

    Lee, K-M; Chapman, R S; Shen, M; Lubin, J H; Silverman, D T; He, X; Hosgood, H D; Chen, B E; Rajaraman, P; Caporaso, N E; Fraumeni, J F; Blair, A; Lan, Q

    2010-01-01

    Background: In Xuanwei County, Yunnan Province, China, lung cancer mortality rates in both males and females are among the highest in China. Methods: We evaluated differential effects of smoking on lung cancer mortality before and after household stove improvement with chimney to reduce exposure to smoky coal emissions in the unique cohort in Xuanwei, China. Effects of independent variables on lung cancer mortality were measured as hazard ratios and 95% confidence intervals using a multivariable Cox regression model that included separate time-dependent variables for smoking duration (years) before and after stove improvement. Results and conclusion: We found that the effect of smoking on lung cancer risk becomes considerably stronger after chimney installation and consequent reduction of indoor coal smoke exposure. PMID:20648014

  17. CFD simulation of a solar tower

    Energy Technology Data Exchange (ETDEWEB)

    Koten, Hasan; Yukselenturk, Yalcyn; Yilmaz, Mustafa [Marmara University Mechanical Engineering Department (Turkey)], E-mail: hasan.koten@marmara.edu.tr

    2011-07-01

    With the depletion of fossil fuels and the rising concerns about their impacts on the environment, the use of alternative energy sources has become necessary. Among the alternatives, solar energy, with its unlimited resources and its low impact on the environment, is the most promising. The aim of this paper is to present a numerical model of a regular solar tower. A CFD analysis of the solar tower was performed with a commercial CFD code and velocity fields, temperature measurements and flow characteristics were determined and compared to experimental results available in the literature. It was found that the numerical model is capable of assessing the buoyant air flow in chimneys. In addition results showed that increasing the solar chimney height, solar collector area, or solar irradiance increases power generation capacity while ambient temperature does not significantly affect this capacity. This study provided a numerical model which is proficient in modeling solar towers.

  18. Preliminary Phenomena Identification and Ranking Tables (PIRT) for SBWR start-up stability

    International Nuclear Information System (INIS)

    Phenomena Identification and Ranking Tables (PIRT) have been developed for start-up transient for SBWP. The information used for PIRT came from RAMONA-4B and TRACG analyses of the transient and from related small scale tests. The transient was divided into four distinct phases, namely, Subcooled Core Heat-up, Subcooled Chimney, Saturated Chimney and Power Ascension. The assessment criterion selected was Minimum Critical Power Ratio. The SBWR system was divided into ten components. A total of 33 distinct phenomena among the components were identified. The Phase I has 28 ranked phenomena with 17 low, 6 medium and 5 high ranking. The Phase II has 39 ranked phenomena with 18 low, 13 median and 8 high ranking. The Phase III has 47 ranked phenomena with 22 low, 10 medium and 15 high ranking. The Phase IV has 46 ranked phenomena with 16 low, 12 medium and 18 high ranking. 12 refs., 22 figs., 21 tabs

  19. Airborne thermography of temperature patterns in sugar beet piles

    Science.gov (United States)

    Moore, D. G.; Bichsel, S.

    1975-01-01

    An investigation was conducted to evaluate the use of thermography for locating spoilage areas (chimneys) within storage piles and to subsequently use the information for the scheduling of their processing. Thermal-infrared quantitative scanner data were acquired initially on January 16, 1975, over the storage piles at Moorhead, Minnesota, both during the day and predawn. Photographic data were acquired during the day mission to evaluate the effect of uneven snow cover on the thermal emittance, and the predawn thermography was used to locate potential chimneys. The piles were examined the day prior for indications of spoilage areas, and the ground crew indicated that no spoilage areas were located using their existing methods. Nine spoilage areas were interpreted from the thermography. The piles were rechecked by ground methods three days following the flights. Six of the nine areas delineated by thermography were actual spoilage areas.

  20. On the Outstanding Historic Listed Buildings Partial Repair Method and Process-- Practical Experiences of the Reconstruction Project of Shanghai Luwan District Sinan Mansions Preservation Transformation Project%浅议优秀历史保护建筑修复部分方法及工艺--上海卢湾区思南公馆保留保护改造项目的改建工程实践心得

    Institute of Scientific and Technical Information of China (English)

    李戟

    2014-01-01

    本文主要对外立面卵石墙面恢复、保护建筑平瓦斜屋面翻新、烟囱的砌筑及原烟囱混凝土顶帽的利用与恢复等进行了分析和探讨,希望能够在行业起到抛砖引玉的作用。%This paper analyzes and discusses the recover of facade pebble metope, restoration of protection building flat inclined roofing tile, masonry of chimney, and utilization and recovery of original concrete chimney hat, hopes to be able to play the role of throwing out a minnow to catch a whale in the industry.

  1. Gas migration pathways, controlling mechanisms and changes in sediment acoustic properties observed in a controlled sub-seabed CO2 release experiment

    OpenAIRE

    Cevatoglu, Melis; Bull, Jonathan M.; Vardy, Mark E.; Gernon, Thomas M.; Wright, Ian C.; Long, David

    2015-01-01

    Highlights • Repeated 2D seismic reflection surveys map migration of CO2 in marine sediments. • CO2 is imaged as bright spots, acoustic blanking, and by reflector terminations. • Seismic chimneys are interpreted as inter-connected micro-scale fractures. • CO2 migration is controlled by stratigraphy and total subsurface gas volume/injection rate. • CO2 changes sediment acoustic properties, including reflectivity and attenuation. Abstract Carbon capture an...

  2. -

    OpenAIRE

    Yunus KARAKUYU; Tortop, Hasan Said

    2009-01-01

    The purpose of this study was to investigate the effects of thought experiments on students? conceptual understanding of Newton?s Laws of Motion and Logical Thinking Ability. The sample of this study consisted of 20 students from eleventh grade in High School. Students did six taught experiments during instruction in cooperative learning environment which included strong man, flies in the jar, dynamics, solar chimney, tunnel through the earth and magnet car. One group pre-post tests quasi exp...

  3. Microbial diversity in a submarine carbonate edifice from the serpentinizing hydrothermal system of the Prony Bay (New Caledonia) over a 6-year period

    OpenAIRE

    POSTEC, Anne; Quéméneur, Marianne; Bes, Méline; Mei, Nan; Benaïssa, Fatma; Payri, Claude; Pelletier, Bernard; Monnin, Christophe; Guentas-Dombrowsky, Linda; Ollivier, Bernard; Gérard, Emmanuelle; Pisapia, Céline; Gérard, Martine; Ménez, Bénédicte; Erauso, Gaël

    2015-01-01

    International audience Active carbonate chimneys from the shallow marine serpentinizing Prony Hydrothermal Field were sampled 3 times over a 6 years period at site ST09. Archaeal and bacterial communities composition was investigated using PCR-based methods (clone libraries, Denaturating Gel Gradient Electrophoresis, quantitative PCR) targeting 16S rRNA genes, methyl coenzyme M reductase A and dissimilatory sulfite reductase subunit B genes. Methanosarcinales (Euryarchaeota) and Thaumarcha...

  4. Microbial diversity in a submarine carbonate edifice from the serpentinizing hydrothermal system of the Prony Bay (New Caledonia) over a 6-year period.

    OpenAIRE

    Anne ePostec; Marianne eQuéméneur; Méline eBes; Nan eMei; Fatma eBenaïssa; Claude ePayri; Christophe eMonnin; Bernard ePelletier; Linda eGuentas; Bernard eOllivier; Emmanuelle eGérard; Céline ePisapia; Martine eGérard; Bénédicte eMénez; Gaël eErauso

    2015-01-01

    Active carbonate chimneys from the shallow marine serpentinizing Prony Hydrothermal Field were sampled 3 times over a 6 years period at site ST09. Archaeal and bacterial communities composition was investigated using PCR-based methods (clone libraries, Denaturating Gel Gradient Electrophoresis, quantitative PCR) targeting 16S rRNA genes, methyl coenzyme M reductase A and dissimilatory sulfite reductase subunit B genes. Methanosarcinales (Euryarchaeota) and Thaumarchaea were the main archaeal ...

  5. Effect of air injection under subsurface drip irrigation on yield and water use efficiency of corn in a sandy clay loam soil

    OpenAIRE

    Mohamed Abuarab; Ehab Mostafa; Mohamed Ibrahim

    2013-01-01

    Subsurface drip irrigation (SDI) can substantially reduce the amount of irrigation water needed for corn production. However, corn yields need to be improved to offset the initial cost of drip installation. Air-injection is at least potentially applicable to the (SDI) system. However, the vertical stream of emitted air moving above the emitter outlet directly toward the surface creates a chimney effect, which should be avoided, and to ensure that there are adequate oxygen for root respiration...

  6. Installation complete / Aet Ader, Kadri Klementi

    Index Scriptorium Estoniae

    Ader, Aet

    2015-01-01

    Linnainstallatsioonidest avalikus ruumis. "Gas Pipe" Venezia Arhitektuuribiennaalil (Maarja Kask, Ralf Lõoke, Neeme Külm, Ingrid Ruudi, 2008). "Artificial Queue" (Andra Aaloe, Aet Ader, Flo Kasearu, Grete Soosalu, 2010). "To the Sea" (autorid Tomomi Hayashi, Mihkel Sagar, 2011). "Chimney" (tundmatu autor, 2011). "Straw Theatre" (Salto Arhitektid, 2011). "A Path in the Forest" (Tetsuo Kondo, Mitsuru Maekita, Mutsuro Sasaki, Yoshiyuki Hiraiwa, 2011). "O" (Aet Ader, Andra Aaloe, Kaarel Künnap, Grete Soosalu, Flo Kasearu, 2011)

  7. Capital Moves

    Institute of Scientific and Technical Information of China (English)

    XIAOCHEN

    2005-01-01

    On November 15, 2004, Wang Jirong, vice director of the State Environmental Protection Administration (SEPA), led a team of officials to the top floor of the CCTV tower in western Beijing. They were there to look at the city's boiler chimneys and identify those belching black-smoke. Under the blue sky, the visibility was extremely good, at around 30 kilometers. But when Wang's eyes shifted to the west, he coul not help noticing a massive smoke cap,

  8. Microbiology of Low Temperature Seafloor Deposits Along a Geochemical Gradient in Lau Basin

    Science.gov (United States)

    sylvan, J. B.; Sia, T. Y.; Haddad, A.; Briscoe, L. J.; Girguis, P. R.; Edwards, K. J.

    2011-12-01

    The East Lau Spreading Center (ELSC) and Valu Fa Ridge comprise a ridge segment in the southwest Pacific Ocean where rapid transitions in the underlying mantle lenses manifest themselves by gradients in seafloor rock geochemistry. At the spreading center in the north, basaltic host rock extrudes while the influence of subduction in the south creates mainly basaltic andesite host rock. A contuous gradient between these two end members exists along the spreading center. We studied the geology and microbial diversity of three silicate rock samples and three inactive sulfide chimney samples collected along the ELSC and Valu Fa Ridge by X-ray diffraction, elemental analysis, thin section analysis and construction of bacterial 16S rRNA clone libraries. Here, we discuss the geological and biological differences between the collected rocks. We found that the bacterial community composition changed as the host rock mineralogy and chemistry changed from north to south. Also, the bacterial community composition on the silicates is distinct from those on the inactive chimneys, and the interior conduit of an inactive chimney hosts a very different community from the exterior. Basalt from the northern end of the ELSC had high proportions of Alphaproteobacteria and Bacteroidetes. These proportions decreased on the silicates collected further south. Epsilonproteobacteria were also present on the basalt, decreased further south and were absent on the basaltic andesite. Conversely, basaltic andesite rocks from the southern end had high proportions of Chloroflexi, which decreased further north and were absent on basalt. The exterior of inactive sulfide structures were dominated by lineages of sulfur oxidizing Gammaproteobacteria and Epsilonproteobacteria and were less diverse than those on the silicates. The interior of one chimney was dominated by sulfate-reducing Deltaproteobacteria and was the least diverse of all samples. These results support the Mantle to Microbe hypothesis in

  9. Reducing childhood illness - fostering growth : an integrated home-based intervention package (IHIP) to improve indoor-air pollution, drinking water quality and child nutrition

    OpenAIRE

    Hartinger Peña, Stella M.

    2014-01-01

    Child mortality attributable to pneumonia, diarrhoea and malnutrition accounts globally for the majority of 8.8 million annual deaths. More than half of these deaths are preventable. Available and effective interventions include safe water supply, household water treatment, improved chimney stoves and personal- and home-hygiene and -health messages. In Peru, the current health services reform is focused on shifting responsibilities to peripheral levels; thus, empowering community organisation...

  10. Waste heat conducting system for side burner regenerative coke oven batteries with divided heating system. [German Patent

    Energy Technology Data Exchange (ETDEWEB)

    Thiersch, F.; Strobel, M.; Schmitz, T.

    1980-08-21

    In the well known waste heat removal system for side burner regenerative coking over batteries with divided heating system both flues could be used simultaneously and equally. The flues in the longitudinal direction of the battery open into a common chimney foot connection at one end of the battery. They are individually connected via opposite groups of transverse flues to opposite groups of waste heat elbows of waste heat valves on the machine and on the coke side.

  11. Toy Blocks and Rotational Physics

    CERN Document Server

    Varieschi, G U; Varieschi, Gabriele U.; Jully, Isabel R.

    2004-01-01

    In this paper we summarize the theory of the "falling chimney," which deals with the breaking of tall structures in mid-air, when they fall to the ground. We describe how to reproduce these effects using small-scale models built with toy blocks. We also present an improved and more effective way to perform and analyze these interesting experiments, by using video capture software together with a digital video camera.

  12. Patología, diagnóstico y recuperación de chimeneas industriales de fábrica de ladrillo cerámico

    OpenAIRE

    Díaz Gómez, C.; Gumá Esteve, R

    1999-01-01

    The work presented in these pages originated from a study commissioned by Barcelona Provincial Council's Architectural Heritage Service, in which data was gathered on a broad sample of brickwork industrial chimneys in order to analyse the factors that have contributed or continue to contribute to their physical deterioration and the progressive jeopardising of their safety. The aspects considered include cracking patterns and damage found, and also data deduced from the analytical evaluation ...

  13. William Blake and His Great Poetry

    Institute of Scientific and Technical Information of China (English)

    邢琳琳

    2009-01-01

    William Blake is the first greatest romantic poet in the 18th century. His poems have a number of features. The Most important poems reflect the social ills, unique conception of childhood and plain direct language, lyric rhyme with immense compression of meaning. And the great poems London and The Chimney Sweeper are the best examples of these features. This paper will present detailed analysis of these three well-known poems by William Blake.

  14. Interaction between groundwater and TBM (Tunnel Boring Machine) excavated tunnels

    OpenAIRE

    Font Capó, Jordi

    2012-01-01

    A number of problems, e.g. sudden inflows are encountered during tunneling under the piezometric level, especially when the excavation crosses high transmissivity areas. These inflows may drag materials when the tunnel crosses low competent layers, resulting in subsidence, chimney formation and collapses. Moreover, inflows can lead to a decrease in head level because of aquifer drainage. Tunnels can be drilled by a tunnel boring machine (TBM) to minimize inflows and groundwater impacts, restr...

  15. Étude numérique et expérimentale du refroidissement des convertisseurs auxiliaires de puissance dans les trains par convection naturelle, film liquide et caloduc

    OpenAIRE

    Zouitene, Saâd

    2014-01-01

    This thesis is about a study and optimization of the cooling electric power converters (CVS) used in trains. These components are heavy, noisy, and are not energetically efficient. We analyze other types of economic and efficient cooling. We used Comsol Multiphysics to study numerically CVS cooling by natural convection using the chimney effect and liquid film by exploiting the phase change to evacuate heat. The numerical results are validated with the results from literature and those obtain...

  16. Asbestos Exposure among Construction Workers During Demolition of Old Houses in Tehran, Iran

    OpenAIRE

    Hossein KAKOOEI; NORMOHAMMADI, Mohhammad

    2013-01-01

    Air quality in demolition practices has seldom been evaluated in Iran. Accordingly, we evaluated asbestos exposure among Tehran construction workers during the demolition of old houses. To identify possible sources of asbestos exposure, including thermal insulations, chimney pipes and cement sheets, were all sampled. This study also were taken the personal air samples to evaluate any asbestos exposure during the demolition. The asbestos fibers found in the samples were analyzed by phase-contr...

  17. The Energy Efficiency of Hot Water Production by Gas Water Heaters with a Combustion Chamber Sealed with Respect to the Room

    OpenAIRE

    Grzegorz Czerski; Andrzej Strugała

    2014-01-01

    This paper presents investigative results of the energy efficiency of hot water production for sanitary uses by means of gas-fired water heaters with the combustion chamber sealed with respect to the room in single-family houses and multi-story buildings. Additionally, calculations were made of the influence of pre-heating the air for combustion in the chimney and air supply system on the energy efficiency of hot water production. CFD (Computational Fluid Dynamics) software was used for calcu...

  18. Analysis of a passive cooled building for the semiarid climate

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, G.N.

    1986-01-01

    The quasi-steady-state analysis of a hostel building for semiarid climatic conditions has been presented by incorporating the effectiveness of various cooling approaches in the analysis. The effect of intermittent use of an exhaust chimney, opening of windows and a desert cooler has also been incorporated in the analysis to study its performance. It is observed that there is an appreciable reduction in the room temperature by intermittent use of various cooling approaches.

  19. Effects of woodsmoke exposure on airway inflammation in rural Guatemalan women.

    Directory of Open Access Journals (Sweden)

    Michael J Guarnieri

    Full Text Available More than two-fifths of the world's population uses solid fuels, mostly biomass, for cooking. The resulting biomass smoke exposure is a major cause of chronic obstructive pulmonary disease (COPD among women in developing countries.To assess whether lower woodsmoke exposure from use of a stove with a chimney, compared to open fires, is associated with lower markers of airway inflammation in young women.We carried out a cross-sectional analysis on a sub-cohort of participants enrolled in a randomized controlled trial in rural Guatemala, RESPIRE.We recruited 45 indigenous women at the end of the 18-month trial; 19 women who had been using the chimney stove for 18-24 months and 26 women still using open fires.We obtained spirometry and induced sputum for cell counts, gene expression of IL-8, TNF-α, MMP-9 and 12, and protein concentrations of IL-8, myeloperoxidase and fibronectin. Exhaled carbon monoxide (CO and 48-hr personal CO tubes were measured to assess smoke exposure.MMP-9 gene expression was significantly lower in women using chimney stoves. Higher exhaled CO concentrations were significantly associated with higher gene expression of IL-8, TNF-α, and MMP-9. Higher 48-hr personal CO concentrations were associated with higher gene expression of IL-8, TNF- α, MMP-9 and MMP-12; reaching statistical significance for MMP-9 and MMP-12.Compared to using an open wood fire for cooking, use of a chimney stove was associated with lower gene expression of MMP-9, a potential mediator of airway remodeling. Among all participants, indoor biomass smoke exposure was associated with higher gene expression of multiple mediators of airway inflammation and remodeling; these mechanisms may explain some of the observed association between prolonged biomass smoke exposure and COPD.

  20. Berkeley Lighting Cone

    Energy Technology Data Exchange (ETDEWEB)

    Lask, Kathleen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gadgil, Ashok [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-10-24

    A lighting cone is a simple metal cone placed on the fuel bed of a stove during ignition to act as a chimney, increasing the draft through the fuel bed. Many stoves tend to be difficult to light due to poor draft through the fuel bed, so lighting cones are used in various parts of the world as an inexpensive accessory to help with ignition.

  1. Endovascular treatment of renal artery occlusion caused by aortic stentgraft migration

    Directory of Open Access Journals (Sweden)

    Stanišić Michał Goran

    2015-04-01

    Full Text Available Renal function impairment during interventional procedures became a real clinical problem. Contrast related nephropathy is the most common cause of renal failure, however, the procedure-related technical troubles may cause unexpected renal dysfunction.Technical failure of EVAR resulting in acute renal dysfunction is presented. The postprocedural occlusion of the right renal artery was treated in chimney technique. Early reintervention allowed the kidney preservation and renal function restoration.

  2. Revestimientos internos cerámicos para chimeneas industriales

    OpenAIRE

    Serradilla Echarri, Jesús

    1985-01-01

    The present article shows the different factors intervening on the study and later setting into service of the internal ceramic liner for industrial chimneys. Firstly they are studied the diverse existing options and later decision as to the solution to be adopted. Also they are specified the physicochemical peculiar characteristics of the material as well as the criterion to folio w with regards to the adecuate dispositive for the material's quality control.En el presente artícul...

  3. New combustion, environment regulations: the answers for natural gas; Nouvelles reglementations, combustion, environnement: les reponses pour le gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    Le Peltier-Marc, A. [Gaz de France (GDF), 75 - Paris (France)

    1997-12-31

    This paper reports on the point of view from Gaz de France (GdF) company concerning the potential consequences of the use of natural gas in combustion systems with respect to the new regulations about combustion and environment. Details concerning the measures relative to the limitation of pollutants in small combustion installations (2 - 20 MW) are given (chimney height, SO{sub x}, NO{sub x} and dusts content in exhaust gases). (J.S.)

  4. Toxic emissions and devalued CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    With reference to the paradigme shift regarding the formation of dioxins in municiplan solid waste incinerators experimental results are taken into account which lead to the suspicion that the same mechanism of de-novo-synthesis also applies to fireplace chimneys. This can explain the dioxin cont...... burning are characterised together with particle and PAH emissions. The positive treatment of wood stove-technology in the Danish strategy for sustainable development (draft 2007) is critically evaluated and approaches to better regulation are identified....

  5. Catalytic Diversity in Alkaline Hydrothermal Vent Systems on Ocean Worlds

    Science.gov (United States)

    Cameron, Ryan D.; Barge, Laura; Chin, Keith B.; Doloboff, Ivria J.; Flores, Erika; Hammer, Arden C.; Sobron, Pablo; Russell, Michael J.; Kanik, Isik

    2016-10-01

    Hydrothermal systems formed by serpentinization can create moderate-temperature, alkaline systems and it is possible that this type of vent could exist on icy worlds such as Europa which have water-rock interfaces. It has been proposed that some prebiotic chemistry responsible for the emergence of life on Earth and possibly other wet and icy worlds could occur as a result ofredox potential and pH gradients in submarine alkaline hydrothermal vents (Russell et al., 2014). Hydrothermal chimneys formed in laboratory simulations of alkaline vents under early Earth conditions have precipitate membranes that contain minerals such as iron sulfides, which are hypothesized to catalyze reduction of CO2 (Yamaguchi et al. 2014, Roldan et al. 2014) leading to further organic synthesis. This CO2 reduction process may be affected by other trace components in the chimney, e.g. nickel or organic molecules. We have conducted experiments to investigate catalytic properties of iron and iron-nickel sulfides containing organic dopants in slightly acidic ocean simulants relevant to early Earth or possibly ocean worlds. We find that the electrochemical properties of the chimney as well as the morphology/chemistry of the precipitate are affected by the concentration and type of organics present. These results imply that synthesis of organics in water-rock systems on ocean worlds may lead to hydrothermal precipitates which can incorporate these organic into the mineral matrix and may affect the role of gradients in alkaline vent systems.Therefore, further understanding on the electroactive roles of various organic species within hydrothermal chimneys will have important implications for habitability as well as prebiotic chemistry. This work is funded by NASA Astrobiology Institute JPL Icy Worlds Team and a NAI Director's Discretionary Fund award.Yamaguchi A. et al. (2014) Electrochimica Acta, 141, 311–318.Russell, M. J. et al. (2014), Astrobiology, 14, 308-43.Roldan, A. (2014) Chem. Comm

  6. Mouse skin tumor initiation-promotion and complete carcinogenesis bioassays: mechanisms and biological activities of emission samples.

    OpenAIRE

    Nesnow, S; Triplett, L L; Slaga, T J

    1983-01-01

    Extracts of soots obtained from various sources were applied to the skin of mice in an effort to identify carcinogens in these mixtures and to link these materials to the etiology of human cancer. Samples of coal chimney soot, coke oven materials, industrial carbon black, oil shale soot, and gasoline vehicle exhaust materials have been examined by this method. The studies reported here have been constructed to compare the carcinogenic and tumorigenic potency of extracts from various particula...

  7. KINERJA PENGELOLAAN LIMBAH HOTEL PESERTA PROPER DAN NON PROPER DI KABUPATEN BADUNG, PROVINSI BALI

    OpenAIRE

    Putri Nilakandi Perdanawati Pitoyo; I Wayan Arthana; I MADE SUDARMA

    2016-01-01

    Bali tourism development can lead to positive and negative impacts that threatening environmental sustainability. This research evaluates the hotel performance of the waste management that includes management of waste water, emission, hazardous, and solid waste by hotel that participate at PROPER and non PROPER. Research using qualitative descriptive method. Not all of non PROPER doing test on waste water quality, chimney emissions quality, an inventory of hazardous waste and solid waste sort...

  8. Start-up behaviour of a passive auto-catalytic recombiner under counter flow conditions: Results of a first orienting experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Berno, E-mail: simon@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Reinecke, Ernst-Arndt, E-mail: e.reinecke@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany); Kubelt, Christian, E-mail: kubelt@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Allelein, Hans-Josef, E-mail: allelein@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany)

    2014-10-15

    Highlights: • We studied the start-up behaviour of a PAR located in a downward-directed flow. • We performed several identical experiments with and without counter flow. • A temporary interference of the establishing chimney flow is observed. • An earlier local start-up of the catalytic reaction occurs under downward flow. • The overall performance of the PAR is not significantly affected. - Abstract: A downward directed wall-near flow represents a typical thermal hydraulic condition inside the LWR containment during a severe accident. In order to efficiently remove hydrogen released into the containment, passive auto-catalytic recombiners (PARs) located close to the containment wall have to establish an internal upward directed chimney flow against this counter flow. In cooperation between RWTH Aachen and the Research Center Jülich, the effect of a downward directed flow on the PAR start-up has been investigated in the REKO-4 test facility at Jülich. The test series includes experiments with identical boundary conditions performed under counter flow conditions as well as in quiescent atmosphere as reference case. Under counter flow conditions, an earlier local start-up of the catalytic reaction on the upper edge of the catalyst sheets was observed. However, the establishment of full PAR operation required more time compared to the reference case. This delay is attributed to a partial inflow of the counter flow into the PAR outlet which interferes with the establishing of a chimney flow promoted by the exothermal catalytic reaction. Once a developed chimney flow inside the PAR is established, no negative effect on the PAR performance could be observed. As expected, the counter flow mixes immediately with the PAR outlet flow dissolving the characteristic plume of hot gases at the PAR outlet.

  9. Big Cost to Families

    Institute of Scientific and Technical Information of China (English)

    MATT; YOUNG

    2006-01-01

    If tobacco multinationals had their way, China might more closely resemble a chimney. So what are the costs of a potentially smokier future in China? Aside from health costs, there could be economically (and educationally) severe ones, according to a new study published in Social Science & Medicine by a Yale professor. Dr. Hong Wang analyzed how the cost of smoking impacts China's critical economic strengths: human capital investment (defined by education and healthcare), risk-taking capacity (defined by...

  10. Formation of hydrothermal deposits at Kings Triple Junction, northern Lau back-arc basin, SW Pacific: The geochemical perspectives

    Science.gov (United States)

    Paropkari, Anil L.; Ray, Durbar; Balaram, V.; Surya Prakash, L.; Mirza, Imran H.; Satyanarayana, M.; Gnaneshwar Rao, T.; Kaisary, Sujata

    2010-04-01

    An inactive hydrothermal field was discovered near Kings Triple Junction (KTJ) in northern Lau back-arc basin during 19th cruise of R/V Akademik Mstislav Keldysh in 1990. The field consisted of a large elongated basal platform 'the pedestal' with several 'small' chimneys on its periphery and one 'main mound' superposed over it. The surrounding region is carpeted with lava pillows having ferromanganese 'precipitate' as infillings. The adjoining second field consisted of small chimney like growths termed as 'Christmas Tree' Field. The basal pedestal, the peripheral chimneys and small 'Christmas Tree' like growths (samples collected by MIR submersibles), though parts of the same hydrothermal field, differ significantly in their mineralogy and elemental composition indicating different history of formation. The pedestal slab consisting of chalcopyrite and pyrite as major minerals and rich in Cu is likely to have formed at higher temperatures than sphalerite dominated peripheral chimney. Extremely low concentration of high field strength elements (e.g. Zr, Hf, Nb and Ta) and enrichment of light REE in these sulfides indicate prominent influence of aqueous arc-magma, rich in subduction components. The oxide growths in the 'Christmas Tree' Field have two distinct layers, Fe rich orange-red basal part which seems to have formed at very low temperature as precipitates from diffused hydrothermal flows from the seafloor whereas Mn rich black surface coating is formed from hydrothermal fluids emanated from the seafloor during another episode of hydrothermal activity. Perhaps this is for the first time such unique hydrothermal oxide growths are being reported in association with hydrothermal system. Here, we discuss the possible processes responsible for the formation of these different hydrothermal deposits based on their mineralogy and geochemistry.

  11. Meaningful Field Trip in Education of Renewable Energy Technologies

    OpenAIRE

    Hasan Said Tortop

    2013-01-01

    Renewable energy sources, in terms of countries‟ obtaining their energy needs from clean and without harming the environment is becoming increasingly important. This situation also requires improving the quality of science education will be given in this field. In this activity, in a field trip to the center for the renewable energy resources technologies, the application of learning cycle model appropriate for constructivist approach is shown. In the example of solar chimney activity accordi...

  12. Continuous enrichment culture and molecular monitoring to investigate the microbial diversity of thermophiles inhabiting deep-sea hydrothermal ecosystems

    OpenAIRE

    POSTEC, Anne; Urios, Laurent; Lesongeur, Francoise; Ollivier, Bernard; Querellou, Joel; Godfroy, Anne

    2005-01-01

    The microflora developing during a continuous enrichment culture from a hydrothermal chimney sample was investigated by molecular methods. The culture was performed in a gas-lift bioreactor under anaerobic conditions, at 90 degrees C and pH 6.5, on a complex medium containing sulfur as the terminal electron acceptor. Archaeal and bacterial diversity was studied. Microorganisms affiliated with the genera Pyrococcus, Marinitoga, and Bacillus were detected through DGGE analysis of 16S rDNA. Addi...

  13. Combining interventions: improved chimney stoves, kitchen sinks and solar disinfection of drinking water and kitchen clothes to improve home hygiene in rural Peru L’association d’interventions - améliorer les cuisinières à bois, mettre en place des éviers, désinfecter l’eau domestique et le linge de cuisine par le solaire – permet d’améliorer l’hygiène dans les foyers ruraux du Pérou Intervenciones combinadas: mejorar las cocinas a leña, instalar fregaderos y desinfectar el agua para beber y los paños de cocina con energía solar para mejorar la higiene en hogares rurales en Perú

    OpenAIRE

    Ana I. Gil; Claudio F Lanata; Hartinger, Stella M.; Jan Hattendorf; Hector Verastegui; Daniel Mäusezahl

    2012-01-01

    Home based interventions are advocated in rural areas against a variety of diseases. The combination of different interventions might have synergistic effects in terms of health improvement and cost effectiveness. However, it is crucial to ensure cultural acceptance. The aim of the study was to develop an effective and culturally accepted home-based intervention package to reduce diarrhoea and lower respiratory illnesses in children. In two rural Peruvian communities we evaluated the performa...

  14. Design of a solar updraft tower power plant for pakistan and its simulation in transys

    International Nuclear Information System (INIS)

    Solar updraft tower is a distinct and novel combination of three old concepts that are green house effect, chimney effect and wind turbine. It can be employed, with almost negligible maintenance cost, in electricity generation. Given the different climatic and economical conditions for different places, every region demands a specific design. As solar chimney power plant is a relatively new technology, much effort has not been done in evaluating the performances of the various plants. In this context, a solar updraft tower has been designed for the conditions of Pakistan (Lahore) and is simulated in TRNSYS to analyze the plant performance through different seasons and time of the year. The study reveals important results about the factors involved in determining the final output power produced. It is observed that the solar irradiance plays a more significant role in power generation than ambient temperature. The more the capacity of a plant to produce power, the more economical it would be. TRNSYS based program is presumed to be a handy mode of examining solar chimney power plants. (author)

  15. Utilization of the noble gases in studies of underground nuclear detonations

    International Nuclear Information System (INIS)

    The Livermore Gas Diagnostics Program employs a number of rare gas isotopes, both stable and radioactive, in its investigations of the phenomenology of underground nuclear detonations. Radioactive gases in a sample are radiochemically purified by elution chromatography, and the separated gases are radioassayed by gamma-ray spectrometry and by internal or thin-window beta proportional counting. Concentrations of the stable gases are determined by mass-spectrometry, following chemical removal of the reactive gases in the sample. The most general application of the noble gases is as device fraction indicators to provide a basis for estimating totals of chimney-gas components. All of the stable rare gases, except argon, have been used as tracers, as have xenon-127 and krypton-85. Argon-37 and krypton-85 have proven to be of particular value in the absence of a good tracer material as reference species for studies of chimney-gas chemistry. The rate of mixing of chimney gases, and the degree to which the sampled gas truly represents the underground gas mixture, can be studied with the aid of the fission-product gases. Radon-222 and helium are released to the cavity from the surrounding rock, and are, therefore, useful in studies of the interaction of the detonation with the surrounding medium

  16. Optimization of vaporization flue circulatory system for converter in Anyang Iron and Steel Group Co., Ltd%安钢转炉汽化烟道循环系统优化

    Institute of Scientific and Technical Information of China (English)

    罗大春; 周友军; 李军强; 马正锋

    2012-01-01

    The vaporization flue circulatory systems were reformed to solve the leakage problems of the fixed chimney cap and the tail flue of the 150 t converter in Anyang Iron & Steel Group Co. , Ltd. An extra pump was added into the old high - pressure pump system to enhance the circulatory cooling water flow, and the natural circulation system of the tail flue was changed for the forced high-pressure circulation system and combined with the forced circulation system of the fixed chimney cap. This optimization measure extended the service life of the fixed chimney cap for more than six months, and decreased the water leakage of tail flue by almost 80%.%针对安钢150 t转炉汽化烟道循环系统固定烟罩、尾部烟道频繁漏水问题,安钢对转炉汽化烟道循环系统进行改造.将原系统设计的l用1备高压泵改为2用1备增加循环冷却水量,并将尾部烟道高压自然循环改为强制循环并入固定烟罩强制循环系统,延长固定烟罩使用寿命6个月以上,减少尾部烟道漏水80%以上.

  17. Magnet News

    CERN Multimedia

    Foussat, A; Ruber, R

    Central Solenoid Test The Central Solenoid (CS) and its associated Proximity Cryogenic System have been designed by KEK in collaboration with CERN. Following construction and extensive tests at the Toshiba manufacturing site in Yokohama, Japan, the equipment has been shipped to CERN. The CS is now being prepared for the integration in a common cryostat with the LAr calorimeter, after which a full on-surface test has to be completed before final installation 100m underground in the ATLAS cavern. For this purpose a provisional set-up for the re- commissioning of the final Proximity Cryogenics, the connecting Chimney and the Central Solenoid has been established. During the month of May the Proximity Cryogenics and Chimney with superconducting bus lines have been tested (figure1). The equipment was cooled down to 4.5K and a current of 9000 amperes was applied to the chimney. This is almost 20% above the nominal operational current of 7400 amperes. A number of tests and simulations have been successfully perf...

  18. Scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX) and aerosol time-of-flight mass spectrometry (ATOFMS) single particle analysis of metallurgy plant emissions.

    Science.gov (United States)

    Arndt, J; Deboudt, K; Anderson, A; Blondel, A; Eliet, S; Flament, P; Fourmentin, M; Healy, R M; Savary, V; Setyan, A; Wenger, J C

    2016-03-01

    The chemical composition of single particles deposited on industrial filters located in three different chimneys of an iron-manganese (Fe-Mn) alloy manufacturing plant have been compared using aerosol time-of-flight mass spectrometry (ATOFMS) and scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX). Very similar types of particles were observed using both analytical techniques. Calcium-containing particles dominated in the firing area of the sintering unit, Mn and/or Al-bearing particles were observed at the cooling area of the sintering unit, while Mn-containing particles were dominant at the smelting unit. SEM-EDX analysis of particles collected downstream of the industrial filters showed that the composition of the particles emitted from the chimneys is very similar to those collected on the filters. ATOFMS analysis of ore samples was also performed to identify particulate emissions that could be generated by wind erosion and manual activities. Specific particle types have been identified for each emission source (chimneys and ore piles) and can be used as tracers for source apportionment of ambient PM measured in the vicinity of the industrial site.

  19. Metagenomic comparison of two Thiomicrospira lineages inhabiting contrasting deep-sea hydrothermal environments.

    Directory of Open Access Journals (Sweden)

    William J Brazelton

    Full Text Available BACKGROUND: The most widespread bacteria in oxic zones of carbonate chimneys at the serpentinite-hosted Lost City hydrothermal field, Mid-Atlantic Ridge, belong to the Thiomicrospira group of sulfur-oxidizing chemolithoautotrophs. It is unclear why Thiomicrospira-like organisms thrive in these chimneys considering that Lost City hydrothermal fluids are notably lacking in hydrogen sulfide and carbon dioxide. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe metagenomic sequences obtained from a Lost City carbonate chimney that are highly similar to the genome of Thiomicrospira crunogena XCL-2, an isolate from a basalt-hosted hydrothermal vent in the Pacific Ocean. Even though T. crunogena and Lost City Thiomicrospira inhabit different types of hydrothermal systems in different oceans, their genomic contents are highly similar. For example, sequences encoding the sulfur oxidation and carbon fixation pathways (including a carbon concentration mechanism of T. crunogena are also present in the Lost City metagenome. Comparative genomic analyses also revealed substantial genomic changes that must have occurred since the divergence of the two lineages, including large genomic rearrangements, gene fusion events, a prophage insertion, and transposase activity. CONCLUSIONS/SIGNIFICANCE: Our results show significant genomic similarity between Thiomicrospira organisms inhabiting different kinds of hydrothermal systems in different oceans, suggesting that these organisms are widespread and highly adaptable. These data also indicate genomic processes potentially associated with the adaptation of these lineages into strikingly different habitats.

  20. Delayed signatures of underground nuclear explosions

    Science.gov (United States)

    Carrigan, Charles R.; Sun, Yunwei; Hunter, Steven L.; Ruddle, David G.; Wagoner, Jeffrey L.; Myers, Katherine B. L.; Emer, Dudley F.; Drellack, Sigmund L.; Chipman, Veraun D.

    2016-03-01

    Radionuclide signals from underground nuclear explosions (UNEs) are strongly influenced by the surrounding hydrogeologic regime. One effect of containment is delay of detonation-produced radioxenon reaching the surface as well as lengthening of its period of detectability compared to uncontained explosions. Using a field-scale tracer experiment, we evaluate important transport properties of a former UNE site. We observe the character of signals at the surface due to the migration of gases from the post-detonation chimney under realistic transport conditions. Background radon signals are found to be highly responsive to cavity pressurization suggesting that large local radon anomalies may be an indicator of a clandestine UNE. Computer simulations, using transport properties obtained from the experiment, track radioxenon isotopes in the chimney and their migration to the surface. They show that the chimney surrounded by a fractured containment regime behaves as a leaky chemical reactor regarding its effect on isotopic evolution introducing a dependence on nuclear yield not previously considered. This evolutionary model for radioxenon isotopes is validated by atmospheric observations of radioxenon from a 2013 UNE in the Democratic People’s Republic of Korea (DPRK). Our model produces results similar to isotopic observations with nuclear yields being comparable to seismic estimates.

  1. Geology, sulfide geochemistry and supercritical venting at the Beebe Hydrothermal Vent Field, Cayman Trough

    Science.gov (United States)

    Webber, Alexander P.; Roberts, Stephen; Murton, Bramley J.; Hodgkinson, Matthew R. S.

    2015-09-01

    The Beebe Vent Field (BVF) is the world's deepest known hydrothermal system, at 4960 m below sea level. Located on the Mid-Cayman Spreading Centre, Caribbean, the BVF hosts high temperature (˜401°C) "black smoker" vents that build Cu, Zn and Au-rich sulfide mounds and chimneys. The BVF is highly gold-rich, with Au values up to 93 ppm and an average Au:Ag ratio of 0.15. Gold precipitation is directly associated with diffuse flow through "beehive" chimneys. Significant mass-wasting of sulfide material at the BVF, accompanied by changes in metal content, results in metaliferous talus and sediment deposits. Situated on very thin (2-3 km thick) oceanic crust, at an ultraslow spreading centre, the hydrothermal system circulates fluids to a depth of ˜1.8 km in a basement that is likely to include a mixture of both mafic and ultramafic lithologies. We suggest hydrothermal interaction with chalcophile-bearing sulfides in the mantle rocks, together with precipitation of Au in beehive chimney structures, has resulted in the formation of a Au-rich volcanogenic massive sulfide (VMS) deposit. With its spatial distribution of deposit materials and metal contents, the BVF represents a modern day analogue for basalt hosted, Au-rich VMS systems.

  2. 3D seismic imaging of marine gas hydrates in Arctic sediments of the Vestnesa Ridge off the W-Svalbard margin

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, C.J.; Bunz, S.; Hustoft, S.; Mienert, J. [Tromso Univ., Tromso (Norway). Dept. of Geology

    2008-07-01

    A gas hydrate and fluid flow dominated sediment drift system at the Vestnesa Ridge offshore W-Svalbard was characterized using high-resolution 3-D seismic data. This ridge represents one of the northernmost gas hydrate provinces that exist along Arctic continental margins. Detailed images revealed seabed pockmarks connected to sub-seabed chimneys that pierce through stratified sediments. The base of the gas hydrate stability zone (BGHSZ) is evident at about 200 ms TWT below seafloor as indicated by a bottom simulating reflector. Increased amplitudes beneath the BGHSZ indicate the existence of large amounts of free gas in the sediment pore space. Variations in lateral amplitude indicate a geological control on the free gas distributions rather than pressure and temperature conditions. The seismic surveys also revealed the internal structure of the acoustic chimneys that act as conduits for fluids and gases rising from greater depth to the seabed. It was suggested that the combination of authigenic carbonate and gas hydrate formation may cause shallow high-reflectivity above the BGHSZ. The fluid flow processes that result in the multifracturing of sediments play a significant role in the evolution of the chimney structures in a gas hydrated sedimentary environment. 21 refs., 7 figs.

  3. Scenarios for solar thermal energy applications in Brazil

    International Nuclear Information System (INIS)

    The Solar and Wind Energy Resource Assessment (SWERA) database is used to prepare and discuss scenarios for solar thermal applications in Brazil. The paper discusses low temperature applications (small and large scale water heating) and solar power plants for electricity production (concentrated solar power plants and solar chimney plants) in Brazil. The results demonstrate the feasibility of large-scale application of solar energy for water heating and electricity generation in Brazil. Payback periods for water heating systems are typically below 4 years if they were used to replace residential electric showerheads in low-income families. Large-scale water heating systems also present high feasibility and many commercial companies are adopting this technology to reduce operational costs. The best sites to set up CSP plants are in the Brazilian semi-arid region where the annual energy achieves 2.2 MW h/m2 and averages of daily solar irradiation are larger than 5.0 kW h/m2/day. The western area of Brazilian Northeastern region meets all technical requirements to exploit solar thermal energy for electricity generation based on solar chimney technology. Highlights: ► Scenarios for solar thermal applications are presented. ► Payback is typically below 4 years for small scale water heating systems. ► Large-scale water heating systems also present high feasibility. ► The Brazilian semi-arid region is the best sites for CSP and chimney tower plants.

  4. Savings on natural gas consumption by doubling thermal efficiencies of balanced-flue space heaters

    Energy Technology Data Exchange (ETDEWEB)

    Juanico, Luis E. [Conicet, and Centro Atomico Bariloche e Instituto Balseiro, Av. Bustillo 9500, 8400 Bariloche, Rio Negro (Argentina); Gonzalez, Alejandro D. [Grupo de Estudios Ambientales, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (Inibioma-Conicet), 8400 Bariloche, Rio Negro (Argentina)

    2008-07-01

    Natural gas is a relatively clean fossil fuel for space heating. However, when it is not used efficiently high consumption can become an environmental problem. In Argentina, individual balanced-flue space heaters are the most extensively used in temperate and cold regions. This furnace is a simple device with a burner set into a metal chamber, separated from the indoor ambient by an enclosing cabinet, and both inlet and outgas chimneys are connected to the outdoor ambient. In previous studies, we measured the performance of these commercial devices, and found very low thermal efficiency (in the range of 39-63% depending on the chimney configuration). The extensive use of these devices is possible due to the availability of unlimited amount of subsidised natural gas to households and businesses. In the present work, we developed a prototype with simple and low cost modifications made on commercial models, and measured the improvements on the thermal efficiency. Findings showed better infrared radiation, enhanced indoor air convection, and passive chimney flow regulation leading to thermal efficiency in the range of 75-85%. These values represent an improvement of 100% when compared to marketed models, and hence, the specific cost of the heater per unit of useful heating power delivered was actually reduced. Considering the large market presence of these furnaces in both residential and business sectors in Argentina, the potential benefits related to gas consumption and environmental emissions are very significant. (author)

  5. Modification of the Core Cooling System of TRIGA 2000 Reactor

    Science.gov (United States)

    Umar, Efrizon; Fiantini, Rosalina

    2010-06-01

    To accomplish safety requirements, a set of actions has to be performed following the recommendations of the IAEA safety series 35 applied to research reactor. Such actions are considered in modernization of the old system, improving the core cooling system and safety evaluations. Due to the complexity of the process and the difficulty in putting the apparatus in the reactor core, analytical and experimental study on the determination of flow and temperature distribution in the whole coolant channel are difficult to be done. In the present work, a numerical study of flow and temperature distribution in the coolant channel of TRIGA 2000 has been carried out using CFD package. For this study, simulations were carried out on 3-D tested model. The model consists of the reactor tank, thermal and thermalizing column, reflector, rotary specimen rack, chimney, fuel element, primary pipe, diffuser, beam tube and a part of the core are constructed by 1.50 million unstructured tetrahedral cell elements. The results show that for the initial condition (116 fuel elements in the core) and for the inlet temperature of 24°C and the primary velocity of 5.6 m/s, there no boiling phenomena occur in the coolant channel. Due to this result, it is now possible to improve the core cooling system of TRIGA 2000 reactor. Meanwhile, forced flow from the diffuser system only affected the flow pattern in the outside of chimney and put on a small effect to the fluid flow's velocity in the inside of chimney.

  6. 4D Time-Lapse Seismic Analysis of Active Gas Seepage Systems on the Vestnesa Ridge, Offshore W-Svalbard

    Science.gov (United States)

    Bunz, S.; Hurter, S.; Plaza-Faverola, A. A.; Mienert, J.

    2014-12-01

    Active gas venting occurs on the Vestnesa Ridge, an elongated sediment drift north of the Molloy Transform and just east of the Molloy Ridge, one of the shortest segments of the slow spreading North-Atlantic Ridge system. The crest of the Vestnesa Ridge at water depth between 1200-1300 m is pierced with fluid-flow features. Seafloor pockmarks vary in size up to 1 km in diameter with significant morphological features consisting of small ridges, diapiric structures and small pits. Detailed hydro-acoustic surveying shows that gas mostly emanates from the small-scale pits, where also hydrates have been recovered by sediment sampling. High-resolution P-Cable 3D seismic data acquired in 2012 show vertical focused fluid flow features beneath the seafloor pockmarks. These co-called chimneys extend down to the free-gas zone underneath a bottom-simulating reflection (BSR). Here, they link up with small fault systems that might provide pathways to the deeper subsurface. The chimney features show a high variability in their acoustic characteristics with alternating blanked or masked zones and high-amplitude anomalies scattered through the whole vertical extent of the chimneys. The amplitude anomalies indicate high-impedance contrasts due to the likely presence of gas or a high-velocity material like gas hydrates or carbonates. In most cases, the high-amplitude anomalies line up along specific vertical pathways that connect nicely with the small-scale pits at the surface where gas bubbles seep from the seafloor. We re-acquired the 3D seismic survey in 2013 for time-lapse seismic studies in order to better understand the origin of the amplitude anomalies and in order to track potentially migrating gas fronts up along the chimney structure. The time-lapse seismic analysis indicates several areas, where gas migration may have led to changes in acoustic properties of the subsurface. These areas are located along chimney structures and the BSR. This work provides a basis for better

  7. Sulfur, carbon, and oxygen isotope variations in submarine hydrothermal deposits of Guaymas Basin, Gulf of California, USA

    Science.gov (United States)

    Peter, J.M.; Shanks, Wayne C., III

    1992-01-01

    Sulfur, carbon, and oxygen isotope values were measured in sulfide, sulfate, and carbonate from hydrothermal chimney, spire, and mound samples in the southern trough of Guaymas Basin, Gulf of California, USA. ??34S values of sulfides range from -3.7 to 4.5%. and indicate that sulfur originated from several sources: 1. (1) dissolution of 0??? sulfide contained within basaltic rocks, 2. (2) thermal reduction of seawater sulfate during sediment alteration reactions in feeder zones to give sulfide with positive ??34S, and 3. (3) entrainment or leaching of isotopically light (negative-??34S) bacteriogenic sulfide from sediments underlying the deposits. ??34S of barite and anhydrite indicate sulfur derivation mainly from unfractionated seawater sulfate, although some samples show evidence of sulfate reduction and sulfide oxidation reactions during mixing within chimneys. Oxygen isotope temperatures calculated for chimney calcites are in reasonable agreement with measured vent fluid temperatures and fluid inclusion trapping temperatures. Hydrothermal fluids that formed calcite-rich chimneys in the southern trough of Guaymas Basin were enriched in 18O with respect to seawater by about 2.4??? due to isotopic exchange with sedimentary and/or basaltic rocks. Carbon isotope values of calcite range from -9.6 to -14.0??? ??34CpDB, indicating that carbon was derived in approximately equal quantities from the dissolution of marine carbonate minerals and the oxidation of organic matter during migration of hydrothermal fluid through the underlying sediment column. Statistically significant positive, linear correlations of ??34S, ??34C, and ??18O of sulfides and calcites with geographic location within the southern trough of Guaymas Basin are best explained by variations in water/rock ( w r) ratios or sediment reactivity within subsurface alteration zones. Low w r ratios and the leaching of detrital carbonates and bacteriogenic sulfides at the southern vent sites result in relatively

  8. Investigating microbial colonization in actively forming hydrothermal deposits using thermocouple arrays

    Science.gov (United States)

    Tivey, M. K.; Reysenbach, A. L.; Hirsch, M.; Steinberg, J.; Flores, G. E.

    2010-12-01

    Investigations of microbial colonization of very young hydrothermal deposits were carried out in 2009 at hydrothermal vents in the Lau Basin (SW Pacific), and in Guaymas Basin, Gulf of California, with a test deployment at the Rainbow vent field on the Mid-Atlantic Ridge in 2008. Our method entailed razing active chimneys and placing arrays of temperature probes (8 titanium-encased probes with their tips placed within a titanium cage) over the active flow. The chimneys that grew back through each array, encasing the temperature probe tips, were recovered after 2 to 15 days, along with temperature records. Molecular phylogenetic methods are being used to reveal the members of the microbial communities that developed in each chimney of known age and thermal history. A total of 15 array deployments were made at 10 vents in 6 different vent fields. Similar morphology beehives (with porous fine-grained interiors and steep temperature gradients across the outermost more-consolidated “wall”) formed at 2 of the 3 vents in Guaymas Basin (in 2 and 5 days at one vent and 3 and 15 days at a second), and at one vent each in the Kilo Moana (in 3 days), Tahi Moana (in 2.5 days), and Tui Malila (in 3 and 8 days) vent fields in the Lau Basin. In contrast, open conduit, thin walled chimneys grew within arrays at the Mariner vent field, Lau Basin, at 3 different vents (in 3 days at one vent, in 3 and 11 days at a second vent, and in 13 days at a third vent). A lower temperature (bacteria with time with initial colonizers being primarily sulfur-oxidizing Epsilonproteobacteria, with members of the Aquificales and Deltaproteobacteria appearing in the 15 day deposit. In contrast, the Archaea showed very little change in diversity over time, with members of the genera Thermococcus and Methanocaldococcus present in all samples analyzed, irrespective of location and timing of sampling. This is very different from a 72-hour test array deployment done in 2008 at Rainbow vent field, where

  9. SDEM modelling of deformation associated with a listric fault system and associated fluid flow

    Science.gov (United States)

    Rasmussen, Marie L.; Clausen, Ole R.; Egholm, David L.; Andresen, Katrine J.

    2016-04-01

    Numerical modelling of geological structures using FEM, DEM and SDEM methods as well as analogue modelling are widely used in order to achieve a better understanding of the kinematics and dynamics during deformation. The methods are furthermore the ultimate source for mapping (observing) the true geometry of geological structures as well as subsurface fluid flow phenomena in 3D seismic data developed for hydrocarbon exploration. Here we use 3D seismic data and SDEM modelling to suggest a dynamic-kinematic evolution of the deformation in the hangingwall of a listric fault overlying an active salt roller. We use the results to obtain a better understanding of the fluid flow in a complex deformed hangingwall. The case study is focused at the D-1 fault trend in the western part of the Norwegian Danish Basin, at the northern slope of the Ringkøbing-Fyn High. The D-1 main fault detaches along the northern flank of a Zechstein salt roller which was active during the Cenozoic. The seismic analysis shows a system of secondary normal antithetic and synthetic faults dipping approximately 50-60dg within the hangingwall. Shallow gas is trapped in the hangingwall and the secondary faults often confine the accumulations i.e. indicating that the secondary faults are sealing. The modelling confirms that the geometry of the secondary faults is highly controlled by the rheology of different layers in the hangingwall but also on the intensity of the salt movement. The modelling also suggests the presence of vertical deformation zones; structures which are not directly observed on the seismic data. The vertical deformation zones are related to the differential vertical movement of the strata due to salt migration. A neural network trained chimney probability cube shows high probabilities for the presence of minor vertical gas chimneys below the gas accumulations suggesting that vertical fluid migration in the hangingwall occurred in areas with significant vertical salt movements. The

  10. Summary of results of underground engineering experience

    International Nuclear Information System (INIS)

    Results pertinent to the use of nuclear explosives in underground engineering applications have been accumulating for the past 10 years from the Plowshare and Weapons tests of the AEC. Thus, predictive and measurement techniques of shock effects and chimney formation were developed in the course of analyzing explosions in granite, salt, and dolomite. The ability to predict effects related specifically to safety has resulted from many measurements on detonations at the Nevada Test Site, where also many of the techniques for handling, emplacing, and firing the explosive have been developed. This gestation period culminated in the execution of Project Gasbuggy, jointly sponsored by industry and government, and the first nuclear explosion in a gasbearing formation. The Gasbuggy explosive had a nominal yield of 25 kt and was detonated 4240 ft below the surface in the San Juan Basin in northwestern New Mexico on December 10, 1967. The shot point was 40 ft below the lower boundary of a 285-ft-thick gas-bearing sandstone formation of very low permeability. No radioactive venting occurred, and no damage to surrounding gas wells or structures resulted. Post-shot geophysical exploration and gas production tests have revealed that the nuclear explosion created a subsurface chimney approximately 160 ft in diameter and 335 ft high. Fractures appear to extend to about 400 ft symmetrically from the detonation point, with shifts or offsets along geological weaknesses extending out to perhaps 750 ft. Presently, radioactive constituents in the gas consist of tritium and krypton-85, with concentrations of approximately 10 μCi/ft3 and 1.5 μCi/ft3 respectively. These concentrations are decreasing a gas withdrawn from the chimney is replaced by formation gas. Tests to evaluate the increase in productivity and ultimate recovery are currently in progress. (author)

  11. Identification and numerical modelling of hydrocarbon leakage in the Lower Congo Basin: Implications on the genesis of km-wide seafloor mounded structures

    Science.gov (United States)

    Anka, Zahie; Ondrak, Robert; Kowitz, Astrid; Schødt, Niels

    2013-09-01

    We present a combined approach of interpretation of 2D seismic-reflection data and numerical modelling of hydrocarbon generation and migration across the southern slope of the Lower Congo Basin, in order to investigate the factors controlling timing and distribution of hydrocarbon leakage in this area. We identified three main families of past and present-day leakage features: (1) Mid-Upper Miocene seismic chimneys concentrated basinwards and ending up on buried pockmarks, (2) Plio-Pleistocene chimneys, rather clustered to the east of the study area and ending up in seafloor pockmarks, and (3) fewer scattered chimneys identified within the Miocene sequences ending up in shallow enhanced reflectors ("Flat spots"). Stratigraphic and structural elements seem to control the distribution of these features. At least two major events of leakage occurred during the Middle-Late Miocene and intermittently during the Pliocene-Present. External factors as sediment supply are associated to the Miocene leakage event, whilst internal structural elements probably triggered the Pliocene to present-day leakage. A major seabed morphological feature, represented by a margin-paralleled belt of more than 1-km-wide mounds, was identified above growth faults to the east of the study area. Data-constrained 2D HC generation and migration modelling suggests a genetic link between these structures and vertical migration/leakage of thermogenic methane sourced from either currently mature Oligo-Miocene source rocks or secondary cracking and further expulsion from over-mature Upper-Cretaceous source rocks. Hence, the mounds are likely to represent a lineation of methane-derived carbonate build-ups. Despite the natural limitations of a 2D migration model, when combined and calibrated with observations from seismic data, it can be used as a valid tool to assess petroleum migration routes in sedimentary basins. To the best of our knowledge, this is the first integrated approach combining both

  12. Characteristics and interpretation of fracture-filled gas hydrate: an example from the Ulleung Basin, East Sea of Korea

    Science.gov (United States)

    Lee, Myung Woong; Collett, Timothy S.

    2013-01-01

    Through the use of 2-D and 3-D seismic data, a total of thirteen sites were selected and drilled in the East Sea of Korea in 2010. A suite of logging-while-drilling (LWD) logs was acquired at each site. LWD logs from the UBGH2-3A well indicate significant gas hydrate in clay-bearing sediments including several zones with massive gas hydrate with a bulk density less than 1.0 g/m3 for depths between 5 and 103 m below the sea floor. The UBGH2-3A well was drilled on a seismically identified chimney structure with a mound feature at the sea floor. Average gas hydrate saturations estimated from the isotropic analysis of ring resistivity and P-wave velocity logs are 80 ± 13% and 47 ± 16%, respectively, whereas they are 46 ± 17% and 45 ± 16%, respectively from the anisotropic analysis. Modeling indicates that the upper part of chimney (between 5 and 45 m below sea floor [mbsf]) is characterized by gas hydrate filling near horizontal fractures (7° dip) and the lower part of chimney (between 45 and 103 mbsf) is characterized by gas hydrate filling high angle fractures on the basis of ring resistivity and P-wave velocity. The anisotropic analysis using P40H resistivity (phase shift resistivity at 32 mHz with 40 inch spacing) and the P-wave velocity yields a gas hydrate saturation of 46 ± 15% and 46 ± 15% respectively, similar to those estimated using ring resistivity and P-wave velocity, but with quite different fracture dip angles. Differences in vertical resolution, depth of investigation, and a finite fracture dimension relative to the tool separation appear to contribute to this discrepancy. Forward modeling of anisotropic resistivity and velocity are essential to identify gas hydrate in fractures and to estimate accurate gas hydrate amounts.

  13. Whole-body monitor, hand-feet monitor, gaseous effluent, area monitor

    International Nuclear Information System (INIS)

    The following gaseous (iodine, noble gases and aerosols) effluents monitoring equipment developed by INVAP may be installed in any nuclear facility with a ventilation system that expels air through a chimney. Should the facility fail to have such a ventilation system - hence the extraction chimney - INVAP can offer an alternative system: a portable gaseous-effluent measuring equipment which can be installed, for example, in the hall of the reactor. Basically, the system consists of forcing, by means of an aspiration pump, a known and fixed air flow fraction from the chimney (or the hall) and to retain the aerosols continuously in a glass microfiber filter. Aerosols are thus measured according to a specially-designed geometry which confronts the filter with the plastic scintillator. The gas thus obtained is free from aerosols. It then passes through a carbon-activated filter which retains iodine. This filter has a coaxial geometry, lodging inside an INa (Tl) gamma radiation-sensitive scintillator. Both scintillators are optically coupled to their respective photomultipliers. Their pulses are processed with a load preamplifier and a discriminating amplifier in order to store them in counters to be periodically read by the intelligent controller. Actual monitoring will be carried out by means of independent measuring channels for iodine and aerosols, with each channel featuring remote reading and alarms (for instance, at the Control Room). Data thus acquired will be processed by an intelligent controller (INVAP Mod. SAPP-09) which will perform the following functions: - Calculation and unit conversion in order to inform in a TRC total and incremental activity released by the installation during a pre-set period established by the operator. - Calculation, including statistical errors, to determine whether incremental alarm values and pre-set totals are adequate or whether they have been exceeded, providing the results. - Process-control operations (counting failure

  14. Evidences of early to late fluid migration from an upper Miocene turbiditic channel revealed by 3D seismic coupled to geochemical sampling within seafloor pockmarks, Lower Congo Basin

    Energy Technology Data Exchange (ETDEWEB)

    Gay, A. [Challenger Division for Seafloor Processes, National Oceanography Centre of Southampton, Southampton (United Kingdom); Lopez, M.; Seranne, M. [Laboratoire Dynamique de la Lithosphere, Universite Montpellier 2, Montpellier (France); Cochonat, P. [Laboratoire Environnements Sedimentaires, Departement Geosciences Marines, IFREMER, Brest (France); Levache, D.; Sermondadaz, G. [TOTAL, Pau (France)

    2006-04-15

    Using high quality 3D seismic data within the Lower Congo Basin (LCB), we have identified pockmarks that are aligned above the sinuous belt of a buried turbiditic palaeo-channel, 1000m beneath the seafloor. Geochemical analyses on cores (GC traces), taken in the centre of four of these pockmarks along this channel, show no clear evidence for migrated oil. But, some features of the GC traces, including elevated baselines (UCM>34{mu}g/g) and a broad molecular weight range of n-alkanes with little odd-even preference, may be interpreted as indicating the presence of thermogenic hydrocarbons in the cores. Seismic profiles show that these pockmarks developed above two main features representative of pore fluid escape during early compaction: (1) closely spaced normal faults affecting the upper 0-800ms TWT of the sedimentary column. This highly faulted interval (HFI) appears as a hexagonal network in plane view, which is characteristic of a volumetrical contraction of sediments in response to pore fluid escape. (2) Buried palaeo-pockmarks and their underlying chimneys seem to be rooted at the channel-levee interface. The chimneys developed during early stages of burial and are now connected to the HFI. This study shows that the buried turbiditic channel now concentrates thermogenic fluids that can migrate through early chimneys and polygonal faults to reach the seafloor within some pockmarks. Using a multidisciplinary approach within the Lower Congo Basin, combining 3D seismic data and geochemical analyses on cores, we trace the fluid history from early compaction expelling pore fluids to later migration of thermogenic hydrocarbons. (author)

  15. A spatiotemporal land-use regression model of winter fine particulate levels in residential neighbourhoods.

    Science.gov (United States)

    Smargiassi, Audrey; Brand, Allan; Fournier, Michel; Tessier, François; Goudreau, Sophie; Rousseau, Jacques; Benjamin, Mario

    2012-07-01

    Residential wood burning can be a significant wintertime source of ambient fine particles in urban and suburban areas. We developed a statistical model to predict minute (min) levels of particles with median diameter of Positioning System device. Route-specific and global land-use regression (LUR) models were developed using the following spatial and temporal covariates to predict 1-min-averaged PM1 levels: chimney density from property assessment data at sampling locations, PM2.5 "regional background" levels of particles with median diameter of <2.5 μm (PM2.5) and temperature and wind speed at hour of sampling, elevation at sampling locations and day of the week. In the various routes travelled, between 49% and 94% of the variability in PM1 levels was explained by the selected covariates. The effect of chimney density was not negligible in "cottage areas." The R(2) for the global model including all routes was 0.40. This LUR is the first to predict PM1 levels in both space and time with consideration of the effects of wood burning emissions. We show that the influence of chimney density, a proxy for wood burning emissions, varies by regions and that a global model cannot be used to predict PM in regions that were not measured. Future work should consider using both survey data on wood burning intensity and information from numerical air quality forecast models, in LUR models, to improve the generalisation of the prediction of fine particulate levels. PMID:22549722

  16. Electrochemical CO2 Reduction by Ni-containing Iron Sulfides: How Is CO2 Electrochemically Reduced at Bisulfide-Bearing Deep-sea Hydrothermal Precipitates?

    International Nuclear Information System (INIS)

    The discovery of deep-sea hydrothermal vents on the late 1970's has led to many hypotheses concerning chemical evolution in the prebiotic ocean and the early evolution of energy metabolism in ancient Earth. Such studies stand on the quest for the bioenergetic evolution to utilize reducing chemicals such as H2 for CO2 reduction and carbon assimilation. In addition to the direct reaction of H2 and CO2, the electrical current passing across a bisulfide-bearing chimney structure has pointed to the possible electrocatalytic CO2 reduction at the cold ocean-vent interface (R. Nakamura, et al. Angew. Chem. Int. Ed. 2010, 49, 7692 − 7694). To confirm the validity of this hypothesis, here, we examined the energetics of electrocatalytic CO2 reduction by iron sulfide (FeS) deposits at slightly acidic pH. Although FeS deposits inefficiently reduced CO2, the efficiency of the reaction was substantially improved by the substitution of Fe with Ni to form FeNi2S4 (violarite), of which surface was further modified with amine compounds. The potential-dependent activity of CO2 reduction demonstrated that CO2 reduction by H2 in hydrothermal fluids was involved in a strong endergonic electron transfer reaction, suggesting that a naturally occurring proton-motive force (PMF) as high as 200 mV would be established across the hydrothermal vent chimney wall. However, in the chimney structures, H2 generation competes with CO2 reduction for electrical current, resulting in rapid consumption of the PMF. Therefore, to maintain the PMF and the electrosynthesis of organic compounds in hydrothermal vent mineral deposits, we propose a homeostatic pH regulation mechanism of FeS deposits, in which elemental hydrogen stored in the hydrothermal mineral deposits is used to balance the consumption of the electrochemical gradient by H2 generation

  17. From Geochemistry to Biochemistry: Simulating Prebiotic Chemistry Driven by Geochemical Gradients in Alkaline Hydrothermal Vents

    Science.gov (United States)

    Barge, Laurie

    2016-07-01

    Planetary water-rock interfaces generate energy in the form of redox, pH, and thermal gradients, and these disequilibria are particularly focused in hydrothermal vent systems where the reducing, heated hydrothermal fluid feeds back into the more oxidizing ocean. Alkaline hydrothermal vents have been proposed as a likely location for the origin of life on the early Earth due to various factors: including the hydrothermal pH / Eh gradients that resemble the ubiquitous electrical / proton gradients in biology, the catalytic hydrothermal precipitates that resemble inorganic catalysts in enzymes, and the presence of electron donors and acceptors in hydrothermal systems (e.g. H2 + CH4 and CO2) that are thought to have been utilized in the earliest metabolisms. Of particular importance for the emergence of metabolism are the mineral "chimneys" that precipitate at the vent fluid / seawater interface. Hydrothermal chimneys are flow-through chemical reactors that form porous and permeable inorganic membranes transecting geochemical gradients; in some ways similar to biological membranes that transect proton / ion gradients and harness these disequilibria to drive metabolism. These emergent chimney structures in the far-from-equilibrium system of the alkaline vent have many properties of interest to the origin of life that can be simulated in the laboratory: for example, they can generate electrical energy and drive redox reactions, and produce catalytic minerals (in particular the metal sulfides and iron oxyhydroxides - "green rust") that can facilitate chemical reactions towards proto-metabolic cycles and biosynthesis. Many of the factors prompting interest in alkaline hydrothermal vents on Earth may also have been present on early Mars, or even presently within icy worlds such as Europa or Enceladus - thus, understanding the disequilibria and resulting prebiotic chemistry in these systems can be of great use in assessing the potential for other environments in the Solar

  18. Computer-simulation study on fire behaviour in the ventilated cavity of ventilated façade systems

    OpenAIRE

    Giraldo María P.; Lacasta Ana; Avellaneda Jaume; Burgos Camila

    2013-01-01

    Fire spread through the façades is widely recognized as one of the fastest pathways of fire spreading in the buildings. Fire may spread through the façade in different ways depending on the type of façade system and on the elements and materials from which it is constructed. Ventilated façades are multilayer systems whose main feature is the creation of an air chamber of circulating air between the original building wall and the external cladding. The “chimney effect” in the air c...

  19. Silo which can be set up or erected out of doors for accommodating a transport or storage container or fuel element can containing at least one radioactive fuel element

    International Nuclear Information System (INIS)

    The silo has a device removing the heat given up to the inside. This contains heat exchanger pipes or ducts passing through, which are sealed to the inside and are taken out on both sides, made of heat conducting material, e.g. aluminium or copper. The ducts run vertically parallel to the longitudinal direction of the container, where the inlets and outlets are higher, so that a chimney effect is obtained. The ducts can run inside in the area of the container jacket, where it is even better if they are in the container jacket. The pipes or ducts are best cast into the concrete of the container jacket. (orig./HP)

  20. Preliminary analysis of the KAERI RCCS Experiment Using GAMMA+

    International Nuclear Information System (INIS)

    This paper describes the analysis of the KAERI RCCS experiment. GAMMA+ code was used for analysis of the RCCS 1/4-scale natural cooling experimental facility designed and built at KAERI to verify the performance of the natural circulation phenomenon. The results obtained from the GAMMA+ analysis showing the temperature profiles and flow rates at steady state were compared with the results from the preliminary experiments conducted in this facility. GAMMA+ analysis for the KAERI RCCS experimental setup was carried out to understand its natural circulation behavior. The air flow rate at the chimney exit achieved by experiments was from to be almost same as that of GAMMA+

  1. Stack disposal and reduction of radioactive gaseous effluents. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The bibliography contains citations concerning the release and dilution of radioactive gaseous waste into the atmosphere via chimney or stack disposal. Measurement, analysis, and monitoring of gas wastes and aerosols are discussed, as well as environmental impacts. Articles also refer to monitoring data from a variety of nuclear facilities including power reactors, experimental reactors and laboratories, and nuclear processing plants. Solid and liquid radioactive waste disposal are referenced in separate bibliographies. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  2. Hydrothermal minerals

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.

    observations and robot controlled sampling 82 Table 1. A compilation of reported metallogenesis along the IORS (Soure: Banerjee & Ray, 2003... 31°04′S/58°58′E 31°11′S/58°30′E 18. 10°N to 11°40′N Anda- Evidence of hydrothermal activity in the Andaman Back arc Basin comprising broken parts of Man chimney structures and rocks with disseminated and vein type metal sulphides. Water depth...

  3. Retrieve of atmospheric SO2 and O3 columns in the UV region using mobile DOAS

    International Nuclear Information System (INIS)

    We present the use of a passive DOAS system to retrieve SO2 and O3 columns emitted by industrial chimneys. It works with software built in LabVIEW and running with a PC linked to mini spectrometer and GPS. The system uses the sun light as light source, a telescope a fiber optic, a mini-spectrometer and a GPS. The spectrometer and the GPS are linked to a PC where the system is controlled and where all data are processed to retrieve the SO2 and O3 slant columns. (Author)

  4. MSM Poems: More Smoke

    Directory of Open Access Journals (Sweden)

    Ajai R. Singh

    2006-03-01

    Full Text Available In the hot sultry fiasco of damp enthusiasms and silver rays in gloomy archives, narcosis and the feeling of melting ice on frozen palms. Arborescent shadows of sorrow in reminiscent silhouettes the rain soaked evening of pouring emotions and grassy long walks on dripping pavementsSeeking out each other.Remember, my dear the sweet faint lavender in the cleft of your breasts hidden from the present and posterity and the knowledge of transience. Looking at the grey skies I think of clear blue water and simmering passions although I've heard you've created a smoke screen from tall chimneys.

  5. Sustainable wood use, decarbonisation of energetic metabolism and forest development

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    Air pollution from wood stoves with PAH, primary particles and chlorinated dioxins (reported according to national estimates of  Danish NERI) is presented as an insoluble problem because of dioxin de-novo-synthesis in chimneys, as it is known from municipal waste incinerators. A trade-off of this...... local pollution against alleged positive impacts of wood (as all biomass) combustion on global climate change because of 'zero carbon dioxide emissions' is rejected, although this resetting to zero is part of the Danish Law on CO2-quota of 2004. These emissions are, on the contrary, aggravated pr. unit...

  6. Evidences of microbial mediation in the formation of MDAC in the Gulf of Cadiz

    Science.gov (United States)

    Magalhaes, V. H.; Pinheiro, L. M.; Birguel, D.; Peckmann, J.; Niemann, H.; Santos, L.; Vasconcelos, C.; McKenzie, J.; Ivanov, M.

    2006-12-01

    The study of methane-derived authigenic carbonates (MDAC) in the Gulf of Cadiz allowed the identification and collection of different types of authigenic carbonates: (I) dolomite crusts, dolomite nodules, chimneys or filled burrows and (II) aragonitic slabs or pavements. Both correspond to the cementation of sediments by the precipitation of authigenic carbonates, and the different lithologic types correspond to different geochemical environment of formation. Authigenic carbonates yielded 13C values indicating methane as the major carbon source with ratios as low as -46.9(per mil PDB). Likewise, the crusts and chimneys can be interpreted as a record of extensive methane seepage in this particular area of the Gulf of Cadiz. SEM observations revealed large amounts of structures and textures that clearly indicate microbial activity. In the cement of the dolomite chimneys, which consists of minor aggregates of rhombohedric calcite, high-Mg calcite and dolomite, SEM observations allowed the identification of a large variety of microbial-induced fabrics, such as: (1) microbial filaments; (2) high Mg-calcite and dolomite crystal aggregates calcifying and mimetizing filaments and flattening themselves against dolomite and calcite minerals; (3) rods with brush-like terminations; (4) dumbbell-like and cauliflower structures. The identification of microbial and mucous biofilms is frequent in aragonite pavements, occurring as a coating, draped between the aragonite fibres and needles of the stromatolitic layers. Also, aragonite batons, ball-capped batons and nanograins are observed. Specific 13C-depleted biomarkers indicators of archaea involved in the anaerobic oxidation of methane (AOM) as PMI, squalane, crocetane/phytane have been identified in dolomite chimney samples. The aragonite crusts showed even better preserved biomarkers. PMI is accompanied by unsaturated derivatives with 1 to 3 double bonds. Several bacterial lipid biomarkers, also with 13C-depleted compositions

  7. The architecture of the porphyry-metal system as a prospecting stratagem in the Southern Rocky Mountains

    Science.gov (United States)

    Neuerburg, George J.

    1978-01-01

    A model of the porphyry-metal system characteristic of the consanguineous Cretaceous and Tertiary igneous rocks and associated ores of the southern Rocky Mountains is constructed from the bits and pieces exposed in the Colorado mineral belt and the San Juan volcanic field. Hydrothermally altered rocks in a part of the areas of mineralized rock associated with the Platoro caldera are matched against the model, to locate and to characterize latent mineral deposits for optimal prospecting and exploration. The latent deposits are two stockwork molybdenite deposits (porphyry-molybdenum) and one or two copper-gold-silver chimney deposits.

  8. Occupation and cancer - follow-up of 15 million people in five Nordic countries

    DEFF Research Database (Denmark)

    Pukkala, Eero; Martinsen, Jan Ivar; Lynge, Elsebeth;

    2009-01-01

    hydrocarbons from the chimney soot, and hairdressers' work environment is also rich in chemical agents. Exposure to the known hepatocarcinogens, the Hepatitis B virus and aflatoxin, is rare in the Nordic countries, and a large proportion of primary liver cancers can therefore be attributed to alcohol...... consumption. The highest risks of liver cancer were seen in occupational categories with easy access to alcohol at the work place or with cultural traditions of high alcohol consumption, such as waiters, cooks, beverage workers, journalists and seamen. The risk of colon cancer has been related to sedentary...

  9. Serpentinization and Life

    Science.gov (United States)

    Kelley; 2003/2005 Science Teams, D. S.

    2005-12-01

    The serendipitous discovery of the Lost City Hydrothermal Field at 30N on the Mid-Atlantic Ridge significantly changed our views about where and how life is sustained on our planet. Investigation of this site shows that it is like no other yet discovered, hosting carbonate chimneys that tower up to 60 m above the seafloor. The field rests on 1-2 my old crust, at a water depth of 800 m and is underlain by variably deformed and altered peridotite with lesser gabbro. An intense interdisciplinary field program in 2003 and a follow-on investigation in 2005 show that geological, biological, and chemical processes are strongly intertwined at this site. Serpentinization reactions in the subsurface produce pH 9-11, 40- 91° C fluids enriched in methane, hydrogen, and other hydrocarbons. Mixing of the high pH fluids with seawater forms nearly monomineralic towers of calcite, aragonite, and brucite. In contrast to the rich diversity of microorganisms typically found in black smoker environments, the warm, porous interiors of the chimneys are dominated by a single phylotype of organisms related to Methanosarcinales, which may be capable of both methane oxidation and production. Other microbes, including an organism related to an anaerobic methane-oxidizing phylotytpe (ANME-1) are present in moderate temperature environments such as the flanges (40° C to 70° C), where there is sustained mixing of pure vent fluids and seawater. They are also present in cool carbonate vein environments (Bacterial colonies grow on the outside of diffusely venting chimneys where they form white to light grey filamentous strands several centimeters in length. Based on 16S rDNA clone libraries there is a relatively high diversity of organisms in these zones that include Eubacteria as well as Archaea. In contrast to the dense macrofaunal assemblages that typify most known high-temperature vent environments, the biomass at Lost City is much smaller. The animals that live within the pores and small

  10. Barite in hydrothermal environments as a recorder of subseafloor processes: a multiple-isotope study from the Loki's Castle vent field.

    Science.gov (United States)

    Eickmann, B; Thorseth, I H; Peters, M; Strauss, H; Bröcker, M; Pedersen, R B

    2014-07-01

    Barite chimneys are known to form in hydrothermal systems where barium-enriched fluids generated by leaching of the oceanic basement are discharged and react with seawater sulfate. They also form at cold seeps along continental margins, where marine (or pelagic) barite in the sediments is remobilized because of subseafloor microbial sulfate reduction. We test the possibility of using multiple sulfur isotopes (δ34S, Δ33S, ∆36S) of barite to identify microbial sulfate reduction in a hydrothermal system. In addition to multiple sulfur isotopes, we present oxygen (δ18O) and strontium (87Sr/86Sr) isotopes for one of numerous barite chimneys in a low-temperature (~20 °C) venting area of the Loki's Castle black smoker field at the ultraslow-spreading Arctic Mid-Ocean Ridge (AMOR). The chemistry of the venting fluids in the barite field identifies a contribution of at least 10% of high-temperature black smoker fluid, which is corroborated by 87Sr/86 Sr ratios in the barite chimney that are less radiogenic than in seawater. In contrast, oxygen and multiple sulfur isotopes indicate that the fluid from which the barite precipitated contained residual sulfate that was affected by microbial sulfate reduction. A sulfate reduction zone at this site is further supported by the multiple sulfur isotopic composition of framboidal pyrite in the flow channel of the barite chimney and in the hydrothermal sediments in the barite field, as well as by low SO4 and elevated H2S concentrations in the venting fluids compared with conservative mixing values. We suggest that the mixing of ascending H2- and CH4-rich high-temperature fluids with percolating seawater fuels microbial sulfate reduction, which is subsequently recorded by barite formed at the seafloor in areas where the flow rate is sufficient. Thus, low-temperature precipitates in hydrothermal systems are promising sites to explore the interactions between the geosphere and biosphere in order to evaluate the microbial impact on

  11. An Interpretation of the Origin of Distribution Anomalies of △C

    Institute of Scientific and Technical Information of China (English)

    帅燕华; 周立发

    2001-01-01

    Zonal distribution of seepage hydrocarbon-induced altered carbonates over oil/gas reservoirs is a common phenomenon observed in the field. The authors considered that the con tinuous production of CO2 within the "alteration chimney" gives rise to a significant difference in physical and chemical properties between its interior and the surrounding country rocks.And it is this difference that has promoted the erosion and precipitation of carbonates, t hus leading to the zonal distribution of seepage hydrocarbon-induced altered carbonates over oil/gas reservoirs. This may be a reasonable interpretation of the phenomenon described above.

  12. An Interpretation of the Origin of Distribution Anomalier of △C

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Zonal distribution of seepage hydrocarbon-induced altereb carbonates over oil/gas reservoirs is a common phenomenon observed in the field.The authors considered that the continuous production of CO2 within the “alteration chimney ”gives rise to a significant difference in physical and chemical properties between its interior and the surrounding country rocks.And it is this difference that has promoted the erosion and precipitation of carbonates,thus leading to the zonal distribution of seepage hydrocarbon-induced altered carbonates over oil/gas reservoirs.This may be a reasonable interpretation of the phenomenon described above.

  13. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 3. Inventory of radionuclides underground at the atolls

    International Nuclear Information System (INIS)

    The objective of Working Group 3 was to independently estimate the underground inventories of radionuclides, at the French nuclear test site on the atolls of Mururoa and Fangataufa, and to estimate the distribution of radionuclides between four major components - lava, rubble, gas and water - that determines the mobility of radionuclides in the geosphere. The group also provided a summary of the critical damage dimensions, such as the cavity radius, fissure zone radius and the height of the chimney. As a lot of dimensional data were provided by the French Liaison Office the focus of this report has been to compare these data with experience gained from other test sites in the world

  14. Õhtutähele : [luuletused] / William Blake ; tlk. Märt Väljataga

    Index Scriptorium Estoniae

    Blake, William

    2004-01-01

    Sisu: Õhtutähele ; Korstnapühkija ; Taevatõusmispüha : "See oli taevatõusmispäev, reas sajad lastepaarid..." ; Saviklomp ja kivike ; Taevatõusmispüha : "Kas on see mõni püha pilt..." ; Korstnapühkija ; Haige roos ; Armastuse aed ; London. Saatesõna lk. 12. Orig.: To the Evening Star ; The chimney sweeper ; Holy thursday (1789) ; The clod and pebble ; Holy thursday (1794) ; Holy thursday (1794) ; The sick rose ; The garden of love ; London

  15. Vertical Transport of Aerosol Particles across Mountain Topography near the Los Angeles Basin

    Science.gov (United States)

    Murray, J. J.; Schill, S.; Freeman, S.; Bertram, T. H.; Lefer, B. L.

    2015-12-01

    Transport of aerosol particles is known to affect air quality and is largely dependent on the characteristic topography of the surrounding region. To characterize this transport, aerosol number distributions were collected with an Ultra-High Sensitivity Aerosol Spectrometer (UHSAS, DMT) during the 2015 NASA Student Airborne Research Program (SARP) in and around the Los Angeles Basin in Southern California. Increases in particle number concentration and size were observed over mountainous terrain north of Los Angeles County. Chemical analysis and meteorological lagrangian trajectories suggest orographic lifting processes, known as the "chimney effect". Implications for spatial transport and distribution will be discussed.

  16. Effects of occupation on risks of avoidable cancers in the Nordic countries

    DEFF Research Database (Denmark)

    Kjaerheim, K; Martinsen, J I; Lynge, E;

    2010-01-01

    ratios (SIRs) were computed. Variation in risk across occupations was generally larger in men than in women. In men, the most consistent cluster with high risk of numerous cancer types included waiters, cooks and stewards, beverage workers, seamen, and chimney sweeps. Two clusters of occupations with...... generally low cancer risks were seen in both men and women. The first one comprised farmers, gardeners, and forestry workers, the second one included groups with high education, specifically those in health and pedagogical work. Although cancer risk varies by occupation, only a smaller part of the variation...

  17. Power electronics solution to dust emissions from thermal power plants

    OpenAIRE

    Vukosavić Slobodan; Popov Nikola; Despotović Željko

    2010-01-01

    Thermal power stations emit significant amounts of fly ash and ultra fine particles into the atmosphere. Electrostatic precipitators (ESP) or electro filters remove flying ashes and fine particles from the flue gas before passing the gas into the chimney. Maximum allowable value of dust is 50 mg/m3 and it requires that the efficiency of the ESPs better than 99 %, which calls for an increase of active surface of the electrodes, hence increasing the filter volume and the weight of steel used fo...

  18. Utilização de zeólita preparada a partir de cinza residuária de carvão como adsorvedor de metais em água

    Directory of Open Access Journals (Sweden)

    Fungaro Denise Alves

    2002-01-01

    Full Text Available Coal ashes produced in coal-fired power plant could be converted into zeolites and can be used as low-cost adsorbents for the treatment of effluents contaminated with high levels of toxic metals. The capacity of synthetic zeolites for the removal of cadmium, zinc and copper ions from aqueous solutions has been investigated under different operating conditions. Zeolite from bottom chimney showed higher removal efficiency for metals ions than zeolite from feed hopper and mixing mill. The results indicated that the treated bottom ash could be applied in environmental technology as an immobilizer of pollutants.

  19. New regulations, combustion, environment: responses for natural gas; Nouvelles reglementations, combustion, environnement: les reponses pour le gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    Le Peltier-Marc, A. [Gaz de France (GDF), 75 - Paris (France). Direction Commerciale

    1997-12-31

    The impacts of the new French regulations concerning low- to medium-power combustion equipment with regards to their energy sources, energy efficiency and pollution control, on natural gas fired boilers, are discussed: lower pollutant emission limits are set for SO{sub 2}, NO{sub x} and ashes. The decree gives new regulations concerning plant location, combustion control systems, plant monitoring and maintenance, and air pollution control measures such as chimney stack height and emission limits. The French national gas utility promotes environmental high performance boilers

  20. Building energy modeling for green architecture and intelligent dashboard applications

    Science.gov (United States)

    DeBlois, Justin

    Buildings are responsible for 40% of the carbon emissions in the United States. Energy efficiency in this sector is key to reducing overall greenhouse gas emissions. This work studied the passive technique called the roof solar chimney for reducing the cooling load in homes architecturally. Three models of the chimney were created: a zonal building energy model, computational fluid dynamics model, and numerical analytic model. The study estimated the error introduced to the building energy model (BEM) through key assumptions, and then used a sensitivity analysis to examine the impact on the model outputs. The conclusion was that the error in the building energy model is small enough to use it for building simulation reliably. Further studies simulated the roof solar chimney in a whole building, integrated into one side of the roof. Comparisons were made between high and low efficiency constructions, and three ventilation strategies. The results showed that in four US climates, the roof solar chimney results in significant cooling load energy savings of up to 90%. After developing this new method for the small scale representation of a passive architecture technique in BEM, the study expanded the scope to address a fundamental issue in modeling - the implementation of the uncertainty from and improvement of occupant behavior. This is believed to be one of the weakest links in both accurate modeling and proper, energy efficient building operation. A calibrated model of the Mascaro Center for Sustainable Innovation's LEED Gold, 3,400 m2 building was created. Then algorithms were developed for integration to the building's dashboard application that show the occupant the energy savings for a variety of behaviors in real time. An approach using neural networks to act on real-time building automation system data was found to be the most accurate and efficient way to predict the current energy savings for each scenario. A stochastic study examined the impact of the

  1. COMPUTATIONAL FLOW MODELLING OF FORMULA-SAE SIDEPODS FOR OPTIMUM RADIATOR HEAT MANAGEMENT

    Directory of Open Access Journals (Sweden)

    C. M. DE SILVA

    2011-02-01

    Full Text Available Formula SAE vehicles, over the program’s history have showcased a myriad of aerodynamic packages, each claiming specific quantitative and qualitative features. This paper attempts to critique differing aerodynamic sidepod designs and their effect upon radiator heat management. Various features from inlet size, sidepod shape and size, presence of an undertray, suspension cover, gills and chimneys are analysed for their effects. Computational Fluid Dynamics (CFD analyses are performed in the FLUENT environment, with the aid of GAMBIT meshing software and SolidWorks modelling.

  2. Iron-Oxidizing Bacteria Found at Slow-Spreading Ridge: a Case Study of Capelinhos Hydrothermal Vent (Lucky Strike, MAR 37°N)

    Science.gov (United States)

    Henri, P. A.; Rommevaux, C.; Lesongeur, F.; Emerson, D.; Leleu, T.; Chavagnac, V.

    2015-12-01

    Iron-oxidizing bacteria becomes increasingly described in different geological settings from volcanically active seamounts, coastal waters, to diffuse hydrothermal vents near seafloor spreading centers [Emerson et al., 2010]. They have been mostly identified and described in Pacific Ocean, and have been only recently found in hydrothermal systems associated to slow spreading center of the Mid-Atlantic Ridge (MAR) [Scott et al., 2015]. During the MoMARSAT'13 cruise at Lucky Strike hydrothermal field (MAR), a new hydrothermal site was discovered at about 1.5 km eastward from the lava lake and from the main hydrothermal vents. This active venting site, named Capelinhos, is therefore the most distant from the volcano, features many chimneys, both focused and diffuses. The hydrothermal end-member fluids from Capelinhos are different from those of the other sites of Lucky Strike, showing the highest content of iron (Fe/Mn≈3.96) and the lowest chlorinity (270 mmol/l) [Leleu et al., 2015]. Most of the chimneys exhibit rust-color surfaces and bacterial mats near diffuse flows. During the MoMARSAT'15 cruise, an active chimney, a small inactive one, and rust-color bacterial mat near diffuse flow were sampled at Capelinhos. Observations by SEM of the hydrothermal samples revealed the presence of iron oxides in an assemblage of tubular "sheaths", assembled "stalks", helical "stalks" and amorphous aggregates. These features are similar to those described from the Loihi iron-mats deposits and argue for the occurrence of iron-oxidizing bacteria. Cultures under micro-aerobic and neutral pH conditions allowed us to isolate strains from the small inactive chimney. Pyrosequencing of the 16S rRNA gene of the isolates and environmental samples will soon be performed, which should confirm the presence of iron-oxidizing bacteria and reveal the organization of bacterial communities in this original and newly discovered hydrothermal site of the slow spreading Mid-Atlantic Ridge. Emerson

  3. Surveying techniques in vibration measurement

    Directory of Open Access Journals (Sweden)

    Kuras Przemyslaw

    2015-01-01

    Full Text Available In order to determine the actual dynamic characteristics of engineering structures, it is necessary to perform direct measurements. The paper focuses on the problem of using various devices to measure vibration, with particular emphasis on surveying instruments. The main tool used in this study is the radar interferometer, which has been compared to: robotic total station, GNSS receivers and sensors (accelerometer and encoder. The results of four dynamic experiments are presented. They were performed on: industrial chimney, drilling tower, railway bridge and pedestrian footbridge. The obtained results have been discussed in terms of the requirements imposed by the standard ISO 4866:2010.

  4. Nonlinear Dynamic Phenomena in Mechanics

    CERN Document Server

    Warminski, Jerzy; Cartmell, Matthew P

    2012-01-01

    Nonlinear phenomena should play a crucial role in the design and control of engineering systems and structures as they can drastically change the prevailing dynamical responses. This book covers theoretical and applications-based problems of nonlinear dynamics concerned with both discrete and continuous systems of interest in civil and mechanical engineering. They include pendulum-like systems, slender footbridges, shape memory alloys, sagged elastic cables and non-smooth problems. Pendulums can be used as a dynamic absorber mounted in high buildings, bridges or chimneys. Geometrical nonlinear

  5. Water activation in a fusion environment

    International Nuclear Information System (INIS)

    Water is activated in a fusion environment by the 16O(n,p)16N reaction. In this work nuclear responses in the magnets, induced by gamma rays from the activated cooling water, for the current design of the International Thermonuclear Experimental Reactor (ITER), are calculated with a detailed Monte Carlo model of the chimney region through which the cooling pipes leave the machine. It is found that, despite a significant dose, the nuclear responses induced by these gamma-rays do not pose an obvious threat to the operation of the magnets. 8 refs., 3 figs., 1 tab

  6. The seismic property of reef flat in the Changxing-Feixianguan Formation, Northwest Sichuan Province, China

    Institute of Scientific and Technical Information of China (English)

    LIU Shu; TANG Jianming; GUO Xusheng; ZHAO Shuang

    2007-01-01

    The development of a carbonate reservoir is dominated by its primary sedimentary environment. Gener-ally, a good reservoir must be the oolite of a bank or bioclas-tics of an organic reef in a marginal mesa, which must deposit on the slope of the mesa. Therefore, the analyses of sequence stratigraphy are the key for predicting the presence of carbonate reservoirs. A typical sequence pattern can be seen in the Puguang gas field. As an independent lithologicalbody, the mechanical property of a reef flat is very different from the surrounding rock, causing stress to concentrate.Stress centralization will, in turn, cause a lot of fractures and faults to develop, and ultimately, result in a gas chimney,which is a seismic smear zone beneath or above the reef flat.Known gas fields, such as the Puguang gas field, also possess gas chimneys. Sequence stratigraphy patterns in the marginal mesa and gas chimney near the reservoir are very obvious in all known fields in southeast and east Sichuan Province.By analyzing the seismic features of all known gas fields, a model to predict carbonate reservoirs has been set up. Using this prediction model, we have found that there is a typical reef flat of the marginal mesa in the Malubei structure of Tongnanba structural belts whose sequence stratigraphy pat-tern is very much like that of the Puguang gas field; and in the Cangxi-Jiulongshan structure, there is another reef flat which is symmetrical to the Malubei reef The Cangxi reef flat pos-sesses the largest platform edge shallow facies domestically found, and has a typical prograding sequence. Its gas chimney is very obvious too. Because the Cangxi reef flat is in the very vicinity of the hydrocarbon kitchen and the depression is much bigger than that of the Puguang gas fields, we predict that there may be a gigascopic gas field in Cangxi County.There may also be a large gas field in the Malubei structure.

  7. Cooling of heat-producing high-level radioactive waste. Chapter 5

    International Nuclear Information System (INIS)

    The effectiveness of cooling of heat-producing high-level radioactive waste in a dry, ventilated storage building, in which the investigated with computer simulations of the temperature for normal operation conditions and for fault situations. The calculations have been performed in two steps. In the first step the complete storage building including inlet channels and chimney has been modelled. In the second step very detailed calculations have been performed with regard to the separate containment cylinders and fission-material elements. The validity of the simulation codes has been carefully tested. (H.W.). 9 refs.; 11 figs.; 2 tabs

  8. Mushroom-Shaped Structures as Tracers of Buoyant Flow in the Galactic Disk

    CERN Document Server

    D'Avillez, M A; Avillez, Miguel A. de; Low, Mordecai-Mark Mac

    2001-01-01

    Recent HI emission observations of the Southern Galactic hemisphere have revealed a mushroom-like structure extending from z=-70 to -450 pc, composed of a stem and a cap. Similar structures occur in three-dimensional simulations of a dynamic galactic disk driven by isolated and clustered supernovae. Using these simulations, we show that hot gas in the Galactic disk that is not evacuated through chimneys expands into the cooler gas of the thick disk, forming mushroom-shaped structures. This new class of objects traces buoyant flow of hot gas into the thick disk.

  9. Methodology of adjustment point in the post treatment of gaseous effluents; Metodologia del punto de ajuste en el post tratamiento de efluentes gaseosos

    Energy Technology Data Exchange (ETDEWEB)

    Vizuet G, J.; Molina, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jvg@nuclear.inin.mx

    2005-07-01

    The methodology to determine the adjustment points of the monitoring system of gaseous discharges is based on the stipulations of the 10CFR20, which are expressed in terms of limit concentrations for the outstanding radionuclides, and of dose limits for the individuals members of the public. Besides the points of liberation properly said, like they are the chimneys of the reactor buildings and of turbine, the points of adjustment of the monitoring instrumentation that watches in real time the discharge of the Treatment system of output gases, to the HVAC of the waste building; they also undergo to the same methodology, with the approaches previously described. (Author)

  10. Geodesy work in the construction of cooling towers of the Temelin nuclear power plant

    International Nuclear Information System (INIS)

    The specifications are described of the cooling tower foundations, the bottom part of the flue chimney and of the cooling tower casing. In view of the cooling tower configuration, the ground control points inside the tower were selected in the pit bottom and the layout and check were performed of the inner tower wall. The methodology of measuring the basic layout network, and of laying out up to the fiftieth (ca. 80 m) and from the 70th (106 m) strip is described. The measurement results are computer-processed. The accuracy is assessed of the cooling tower construction in the Temelin nuclear power plant. (E.J.). 1 fig., 5 refs

  11. Artificial wind, tall is beautiful: examination of profitability gain prospects of a renewable energy already almost profitable; Vent artificiel, tall is beautiful: examen des perspectives de gains de rentabilite d'une energie renouvelable deja presque rentable

    Energy Technology Data Exchange (ETDEWEB)

    Bonnelle, D.

    2003-07-01

    A 1000 m height concrete tower covered with 5 km{sup 2} of solar panels will be built in the Australian desert (New South Wales). The air heated by the solar panels will be canalized towards a 130 m diameter chimney in order to create a permanent air flow of 35 to 50 km/h. This artificial wind will move 32 turbines for a maximum total power generation of 200 MW. This book makes both a physical and economical analysis of this project. (J.S.)

  12. Mitigation of the effects of sulphur pollution

    Energy Technology Data Exchange (ETDEWEB)

    Chang, B.; Wilson, R.

    1976-07-05

    As an introduction to the discussion of mitigation of the effects of SO/sub 2/, its health effect on man and the use of sulfates as indicators of the health hazard are first considered. The use of tall chimney stacks and intermittent control and other schemes to reduce the SO/sub 2/ release to the atmosphere are discussed. The problems of administration and forecasting are analyzed and legal problems associated with SO/sub 2/ control are reviewed. In an appendix an analysis of federal jurisdiction over interstate pollution and possible avenues of litigation open to the states is presented. (JSR)

  13. Microcontroller-Based Fault Tolerant Data Acquisition System For Air Quality Monitoring And Control Of Environmental Pollution

    Directory of Open Access Journals (Sweden)

    Tochukwu Chiagunye

    2015-08-01

    Full Text Available ABSTRACT The design applied Passive fault tolerance to a microcontroller based data acquisition system to achieve the stated considerations where redundant sensors and microcontrollers with associated circuitry were designed and implemented to enable measurement of pollutant concentration information from chimney vents in two industry. Microsoft visual basic was used to develop a data mining tool which implemented an underlying artificial neural network model for forecasting pollutant concentrations for future time periods. The feed forward back propagation method was used to train the ANN model with a training data set while a decision tree algorithm was used to select an optimal output result for the model from its two output neurons.

  14. Thermal stability of ESR signals in hydrothermal barites

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Fumihiro [Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005 (Japan); Toyoda, Shin, E-mail: toyoda@dap.ous.ac.jp [Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005 (Japan); Banerjee, Debabrata [Department of Applied Physics, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005 (Japan); Planetary Sciences Division, Physical Research Laboratory, Ahmedabad 380009 (India); Ishibashi, Jun-Ichiro [Department of Earth and Planetary Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

    2011-09-15

    Thermal stability of the ESR signals from barites in chimneys deposited from hydrothermal vents is investigated using isothermal and isochronal annealing experiments. A combination of first and second order kinetics is required to explain the results. The Arrhenius plots of the decay rate constants give the activation energies of 1.0-1.3 eV. From the estimated decay rate constants at the sea bottom (3 {sup o}C), the decay rate of the signal was calculated to be less than 2% for the period of 20 ka, suggesting the applicability of the ESR method for dating barites up to about twenty thousand years.

  15. Analysis of a natural exhaust fan in a building of houses through thermal simulations and CFD; Analisis de un sistema de ventilacion natural en un edificio de viviendas a traves de simulaciones termicas y CFD

    Energy Technology Data Exchange (ETDEWEB)

    Bueno, B.; Cejudo, J.; Carrillo, A.

    2008-07-01

    Computational fluid dynamics (CFD) application to building energy simulation (STE) allows better modelling of indoor air performance and therefore it can be used to optimize the design of natural ventilation systems. In this paper, a natural ventilation system based on thermal chimney applied to a residential building is analyzed. Energy Plus simulations are applied to an apartment and results are coupled to CFD simulations to determine ventilation rates and study convection in the space. CFD simulations are also applied to evaluate indoor air distribution and study how ventilation rate is affected by the pressure drop at ventilation grilles. (Author)

  16. Integral models for buoyant plume calculations

    International Nuclear Information System (INIS)

    Integral models have been proven to be successful and inexpensive tools for the solution of a variety of jet-type environmental flow problems. In the Sonderforschungsbereich 80, a family of integral models has been developed for several applications as, e.g., the mixing of waste water and cooling water plumes discharged into lakes and coastal waters for the dispersion of pollutants and heat emitted by chimneys, cooling towers and urban heat islands into the atmosphere. The common features of these integral models are discussed. Finally, the quality of model results is demonstrated by comparing predictions with experimental data. (orig.)

  17. A power generator associated with a heat accumulator and with a device using fossil fuel

    International Nuclear Information System (INIS)

    The invention provides improvements in motive power installations with a heat accumulator. The exhaust gases of a gas turbine give up their heat to a coolant fluid prior to being evacuated through a chimney. The heat thus transferred is stored in a liquid medium in a tank and is used by a steam cycle expansion engine according to requirements. The turbine combustion chamber is fed with fuel at least partly from said tank, which permits to renew the contents thereof. This can be applied to thermal power stations supplying a network with variable requirements

  18. Applicability of best-estimate analysis TRACE in terms of natural circulation BWR stability

    International Nuclear Information System (INIS)

    As a part of the international CAMP-Program of the US Nuclear Regulatory Commission (USNRC), the best-estimate code TRACE is validated with the stability database of SIRIUS-N Facility at high pressure. The TRACE code analyzed is version 5 patch level 2. The SIRIUS-N facility simulates thermal-hydraulics of the economic simplified BWR (ESBWR). The oscillation period correlates well with bubble transit time through the chimney region regardless of the system pressure, inlet subcooling and heat flux. Numerical results exhibits type-I density wave oscillation characteristics, since core inlet restriction shifts stability boundary toward the higher inlet subcooling, and chimney exit restriction enlarges instability region and oscillation amplitude. Stability maps in reference to the subcooling and heat flux obtained from the TRACE code agrees with those of the experimental data at 1 MPa. As the pressure increases from 2 MPa to 7.2 MPa, numerical results become much stable than the experimental results. This is because that two-phase frictional loss is underestimate, since the natural circulation flow rate of numerical results is higher by approximately 20% than that of experimental results. (author)

  19. Assessment of air pollutant emissions from brick kilns

    Science.gov (United States)

    Rajarathnam, Uma; Athalye, Vasudev; Ragavan, Santhosh; Maithel, Sameer; Lalchandani, Dheeraj; Kumar, Sonal; Baum, Ellen; Weyant, Cheryl; Bond, Tami

    2014-12-01

    India has more than 100,000 brick kilns producing around 250 billion bricks annually. Indian brick industry is often a small scale industry and third largest consumer of coal in the country. With the growing demand for building materials and characterised by lack of pollution control measures the brick industry has a potential to cause adverse effects on the environment. This paper presents assessment of five brick making technologies based on the measurements carried out at seventeen individual brick kilns. Emissions of PM, SO2, CO and CO2 were measured and these emissions were used to estimate the emission factors for comparing the emissions across different fuel or operating conditions. Estimated emission from brick kilns in South Asia are about 0.94 million tonnes of PM; 3.9 million tonnes of CO and 127 million tonnes of CO2 per year. Among various technologies that are widely used in India, Zig zag and vertical shaft brick kilns showed better performance in terms of emissions over the traditional fixed chimney Bull's trench kilns. This suggests that the replacement of traditional technologies with Zig zag, vertical shaft brick kilns or other cleaner kiln technologies will contribute towards improvements in the environmental performance of brick kiln industry in the country. Zig zag kilns appear to be the logical replacement because of low capital investment, easy integration with the existing production process, and the possibility of retrofitting fixed chimney Bull's trench kilns into Zig zag firing.

  20. Microbial diversity in a submarine carbonate edifice from the serpentinizing hydrothermal system of the Prony Bay (New Caledonia over a 6-year period.

    Directory of Open Access Journals (Sweden)

    Anne ePostec

    2015-08-01

    Full Text Available Active carbonate chimneys from the shallow marine serpentinizing Prony Hydrothermal Field were sampled 3 times over a 6 years period at site ST09. Archaeal and bacterial communities composition was investigated using PCR-based methods (clone libraries, Denaturating Gel Gradient Electrophoresis, quantitative PCR targeting 16S rRNA genes, methyl coenzyme M reductase A and dissimilatory sulfite reductase subunit B genes. Methanosarcinales (Euryarchaeota and Thaumarchaea were the main archaeal members. The Methanosarcinales, also observed by epifluorescent microscopy and FISH, consisted of two phyotypes that were previously solely detected in two other serpentinitzing ecosystems (The Cedars and Lost City Hydrothermal Field. Surprisingly, members of the hyperthermophilic order Thermococcales were also found which may indicate the presence of a hot subsurface biosphere. The bacterial community mainly consisted of Firmicutes, Chloroflexi, Alpha-, Gamma-, Beta- and Delta-proteobacteria and of the candidate division NPL-UPA2. Members of these taxa were consistently found each year and may therefore represent a stable core of the indigenous bacterial community of the PHF chimneys. Firmicutes isolates representing new bacterial taxa were obtained by cultivation under anaerobic conditions. Our study revealed diverse microbial communities in PHF ST09 related to methane and sulfur compounds that share common populations with other terrestrial or submarine serpentinizing ecosystems.

  1. Microbial diversity in a submarine carbonate edifice from the serpentinizing hydrothermal system of the Prony Bay (New Caledonia) over a 6-year period.

    Science.gov (United States)

    Postec, Anne; Quéméneur, Marianne; Bes, Méline; Mei, Nan; Benaïssa, Fatma; Payri, Claude; Pelletier, Bernard; Monnin, Christophe; Guentas-Dombrowsky, Linda; Ollivier, Bernard; Gérard, Emmanuelle; Pisapia, Céline; Gérard, Martine; Ménez, Bénédicte; Erauso, Gaël

    2015-01-01

    Active carbonate chimneys from the shallow marine serpentinizing Prony Hydrothermal Field were sampled 3 times over a 6 years period at site ST09. Archaeal and bacterial communities composition was investigated using PCR-based methods (clone libraries, Denaturating Gel Gradient Electrophoresis, quantitative PCR) targeting 16S rRNA genes, methyl coenzyme M reductase A and dissimilatory sulfite reductase subunit B genes. Methanosarcinales (Euryarchaeota) and Thaumarchaea were the main archaeal members. The Methanosarcinales, also observed by epifluorescent microscopy and FISH, consisted of two phylotypes that were previously solely detected in two other serpentinitzing ecosystems (The Cedars and Lost City Hydrothermal Field). Surprisingly, members of the hyperthermophilic order Thermococcales were also found which may indicate the presence of a hot subsurface biosphere. The bacterial community mainly consisted of Firmicutes, Chloroflexi, Alpha-, Gamma-, Beta-, and Delta-proteobacteria and of the candidate division NPL-UPA2. Members of these taxa were consistently found each year and may therefore represent a stable core of the indigenous bacterial community of the PHF chimneys. Firmicutes isolates representing new bacterial taxa were obtained by cultivation under anaerobic conditions. Our study revealed diverse microbial communities in PHF ST09 related to methane and sulfur compounds that share common populations with other terrestrial or submarine serpentinizing ecosystems. PMID:26379636

  2. Numerical Analysis including Pressure Drop in Oscillating Water Column Device

    Science.gov (United States)

    das Neves Gomes, Mateus; Domingues dos Santos, Elizaldo; Isoldi, Liércio André; Rocha, Luiz Alberto Oliveira

    2015-06-01

    The wave energy conversion into electricity has been increasingly studied in the last years. There are several proposed converters. Among them, the oscillatingwater column (OWC) device has been widespread evaluated in literature. In this context, the main goal of this work was to perform a comparison between two kinds of physical constraints in the chimney of the OWC device, aiming to represent numerically the pressure drop imposed by the turbine on the air flow inside the OWC. To do so, the conservation equations of mass,momentumand one equation for the transport of volumetric fraction were solved with the finite volume method (FVM). To tackle thewater-air interaction, the multiphase model volume of fluid (VOF)was used. Initially, an asymmetric constraint inserted in chimney duct was reproduced and investigated. Subsequently, a second strategywas proposed,where a symmetric physical constraint with an elliptical shapewas analyzed. Itwas thus possible to establish a strategy to reproduce the pressure drop in OWC devices caused by the presence of the turbine, as well as to generate its characteristic curve.

  3. A review of standards related to biomass combustion

    Energy Technology Data Exchange (ETDEWEB)

    Villeneuve, J.; Savoie, P. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada)

    2010-07-01

    Air quality is evaluated by the concentration of particulate matter (PM) per unit of air volume. PM10 refers to all particles smaller than 10 micrometers in diameter. The European Commission has established acceptable levels of PM10, but the rules are less precise for evaluating the amount of PM that can be emitted from a furnace's chimney. The province of Quebec allows up to 340 mg/m{sup 3} of PM for large furnaces and 600 mg/m{sup 3} for smaller furnaces. Although wood products can be burned in the province, the burning of all other biomass such as straw, stover and grass is forbidden. The City of Vancouver has stricter emissions standards for PM, notably 50 mg/m{sup 3} for large furnaces and 35 mg/m{sup 3} for smaller furnaces. The reason for this difference is that most furnaces in Quebec are used in rural areas whereas the densely populated City of Vancouver must control emissions at the source. It was concluded that although a universal standard on combustion emissions is not feasible because of different socio-economic conditions and population density, furnaces should emit levels of PM which decrease as the surrounding area population concentration increases. Stringent regulations may be met through advances in technology such as chimney height, bag filters, multicyclones, and precipitators.

  4. 台车加热炉的节能技术改造%Energy-Saving Technical Renovation on Car-Bottom Heating Furnace

    Institute of Scientific and Technical Information of China (English)

    卫同印; 邱峰; 孙翰文

    2013-01-01

    The Chinese 1st successfully application of coke oven gas burning, air single-regenerative, completely use of flue-gas, no-chimney on furnace body type with the combustion system of extreme energy saving technology renovation on car-bottom heating furnace is introduced. The energy-saving efficiency of this technique is 15% more than the heating furnaces those are widely use air single-regenerative, auxiliary chimney on furnace body type ones and 40% more than the ordinary burner with recuperator type ones. So, this technique raises the regenerative combustion technologies to a higher level.%介绍了中国首例燃焦炉煤气,空气单蓄热、全烟气利用,取消了炉体烟囱的燃烧系统近极限节能台车式加热炉改造后运行状况.比目前普遍采用的空气单蓄热、炉体带辅助烟道的加热炉节能15%以上,获得了比常规烧嘴配有换热器的加热炉节能40%以上的良好效果,将蓄热式燃烧技术提高到一个新水平.

  5. Arsenic speciation in food chains from mid-Atlantic hydrothermal vents

    Science.gov (United States)

    Taylor, Vivien F.; Jackson, Brian P.; Siegfried, Matthew R.; Navratilova, Jana; Francesconi, Kevin A.; Kirshtein, Julie; Voytek, Mary

    2012-01-01

    Arsenic concentration and speciation were determined in benthic fauna collected from the Mid-Atlantic Ridge hydrothermal vents. The shrimp species, Rimicaris exoculata, the vent chimney-dwelling mussel, Bathymodiolus azoricus, Branchipolynoe seepensis, a commensal worm of B. azoricus and the gastropod Peltospira smaragdina showed variations in As concentration and in stable isotope (δ13C and δ15N) signature between species, suggesting different sources of As uptake. Arsenic speciation showed arsenobetaine to be the dominant species in R. exoculata, whereas in B. azoricus and B. seepensis arsenosugars were most abundant, although arsenobetaine, dimethylarsinate and inorganic arsenic were also observed, along with several unidentified species. Scrape samples from outside the vent chimneys covered with microbial mat, which is a presumed food source for many vent organisms, contained high levels of total As, but organic species were not detectable. The formation of arsenosugars in pelagic environments is typically attributed to marine algae, and the pathway to arsenobetaine is still unknown. The occurrence of arsenosugars and arsenobetaine in these deep sea organisms, where primary production is chemolithoautotrophic and stable isotope analyses indicate food sources are of vent origin, suggests that organic arsenicals can occur in a foodweb without algae or other photosynthetic life.

  6. Microbial diversity in deep-sea sediments from the Menez Gwen hydrothermal vent system of the Mid-Atlantic Ridge.

    Science.gov (United States)

    Cerqueira, Teresa; Pinho, Diogo; Egas, Conceição; Froufe, Hugo; Altermark, Bjørn; Candeias, Carla; Santos, Ricardo S; Bettencourt, Raul

    2015-12-01

    Deep-sea hydrothermal sediments are known to support remarkably diverse microbial consortia. Cultureindependent sequence-based technologies have extensively been used to disclose the associated microbial diversity as most of the microorganisms inhabiting these ecosystems remain uncultured. Here we provide the first description of the microbial community diversity found on sediments from Menez Gwen vent system. We compared hydrothermally influenced sediments, retrieved from an active vent chimney at 812 m depth, with non-hydrothermally influenced sediments, from a 1400 m depth bathyal plain. Considering the enriched methane and sulfur composition of Menez Gwen vent fluids, and the sediment physicochemical properties in each sampled area, we hypothesized that the site-associated microbes would be different. To address this question, taxonomic profiles of bacterial, archaeal and micro-eukaryotic representatives were studied by rRNA gene tag pyrosequencing. Communities were shown to be significantly different and segregated by sediment geographical area. Specific mesophilic, thermophilic and hyperthermophilic archaeal (e.g., Archaeoglobus, ANME-1) and bacterial (e.g., Caldithrix, Thermodesulfobacteria) taxa were highly abundant near the vent chimney. In contrast, bathyal-associated members affiliated to more ubiquitous phylogroups from deep-ocean sediments (e.g., Thaumarchaeota MGI, Gamma- and Alphaproteobacteria). This study provides a broader picture of the biological diversity and microbial biogeography, and represents a preliminary approach to the microbial ecology associated with the deep-sea sediments from the Menez Gwen hydrothermal vent field.

  7. Accidental Coverage of Both Renal Arteries during Infrarenal Aortic Stent-Graft Implantation: Cause and Treatment

    Directory of Open Access Journals (Sweden)

    Umberto Marcello Bracale

    2014-01-01

    Full Text Available The purpose of this paper is to report a salvage maneuver for accidental coverage of both renal arteries during endovascular aneurysm repair (EVAR of an infrarenal abdominal aortic aneurysm (AAA. A 72-year-old female with a 6 cm infrarenal abdominal aortic aneurysm was treated by endovascular means with a standard bifurcated graft. Upon completing an angiogram, both renal arteries were found to be accidentally occluded. Through a left percutaneous brachial approach, the right renal artery was catheterized and a chimney stent was deployed; however this was not possible for the left renal artery. A retroperitoneal surgical approach was therefore carried out with a retrograde chimney stent implanted to restore blood flow. After three months, both renal arteries were patent and renal function was not different from the baseline. Both endovascular with percutaneous access via the brachial artery and open retroperitoneal approaches with retrograde catheterization are feasible rescue techniques to recanalize the accidentally occluded renal arteries during EVAR.

  8. Leidenfrost phenomenon on conical surfaces

    Science.gov (United States)

    Hidalgo-Caballero, S.; Escobar-Ortega, Y.; Pacheco-Vázquez, F.

    2016-09-01

    The Leidenfrost state is typically studied by placing droplets on flat or slightly curved surfaces. Here this phenomenon is investigated by depositing water in hot conical bowls. We found that this phase exists even for large amounts of liquid in very narrow cones without considerable effect of the confinement on the Leidenfrost transition temperature TL. At a fixed temperature, T >TL , the total evaporation time τ has a nonmonotonic dependence on the angle of confinement θ : for large volumes (˜20 ml) on flat surfaces (θ ˜0∘ ), vapor chimneys appear and accelerate the evaporation rate, their frequency diminishes as θ augments and becomes zero at a certain angle θc, at which τ reaches its maximum value; then, τ decreases again at larger angles because the vapor layer holding up the water becomes thinner due to the increase of hydrostatic pressure and because the geometry facilitates the vapor expulsion along the conical wall. For small volumes (˜1 ml), surface tension mainly determines the drop curvature and the lifetime is practically independent of θ . Different chimney regimes and oscillation patterns were observed and summarized in a phase diagram. Finally, we developed a simple model to decipher the shape adopted by the liquid volume and its evolution as a function of time, and the predictions are in good agreement with the experimental results.

  9. Energetics of the Beamed Zombie Turbulence Maser Action Mechanism for Remote Detection of Submerged Oceanic Turbulence

    Science.gov (United States)

    Gibson, C. H.; Bondur, V. G.; Keeler, R. N.; Leung, P. T.

    2011-11-01

    Sea surface brightness spectral anomalies from a Honolulu municipal outfall have been detected from space satellites in 200 km2 areas extending 20 km from the wastewater diffuser (Bondur 2005, Keeler et al. 2005, Gibson et al. 2005). Dropsonde and towed body microstructure measurements show outfall enhanced viscous and temperature dissipation rates above the turbulence trapping layer. Fossil turbulence waves and secondary (zombie, zebra) turbulence waves break as they propagate near-vertically and then break again near the surface to produce wind ripple smoothing in narrow frequency band (zebra) patterns from soliton-like sources of secondary turbulence energy acting on fossils advected from the outfall. The 30-250 m solitons reflect a nonlinear cascade from tidal and current kinetic energy to boundary layer turbulence events, to fossil turbulence waves, to internal soliton and tidal waves. Secondary (zombie) turbulence acts on outfall fossil patches to amplify, channel in chimneys, and vertically beam ambient internal wave energy just as energized metastable molecules around stars amplify and beam quantum frequencies in astrophysical masers. Kilowatts of buoyancy power from the treatment plant produces fossil turbulence patches trapped below the thermocline. Beamed zombie turbulence maser action (BZTMA) in mixing chimneys amplifies these kilowatts into the megawatts of surface turbulence dissipation required to affect brightness on wide sea surface areas by maser action vertical beaming of fossil-wave-power extracted from gigawatts dissipated by intermittent bottom turbulence events on topography from the tides and currents.

  10. The Energy Efficiency of Hot Water Production by Gas Water Heaters with a Combustion Chamber Sealed with Respect to the Room

    Directory of Open Access Journals (Sweden)

    Grzegorz Czerski

    2014-08-01

    Full Text Available This paper presents investigative results of the energy efficiency of hot water production for sanitary uses by means of gas-fired water heaters with the combustion chamber sealed with respect to the room in single-family houses and multi-story buildings. Additionally, calculations were made of the influence of pre-heating the air for combustion in the chimney and air supply system on the energy efficiency of hot water production. CFD (Computational Fluid Dynamics software was used for calculation of the heat exchange in this kind of system. The studies and calculations have shown that the use of gas water heaters with a combustion chamber sealed with respect to the room significantly increases the efficiency of hot water production when compared to traditional heaters. It has also been proven that the pre-heating of combustion air in concentric chimney and air supply ducts essentially improves the energy efficiency of gas appliances for hot water production.

  11. Characteristics of microbial communities in crustal fluids in a deep-sea hydrothermal field of the Suiyo Seamount

    Directory of Open Access Journals (Sweden)

    Shingo eKato

    2013-04-01

    Full Text Available To directly access the sub-seafloor microbial communities, seafloor drilling has been done in a deep-sea hydrothermal field of the Suiyo Seamount, Izu-Bonin Arc, Western Pacific. In the present study, crustal fluids were collected from the boreholes, and the bacterial and archaeal communities in the fluids were investigated by culture-independent molecular analysis based on 16S rRNA gene sequences. Bottom seawater, sands, rocks, sulfide mound and chimneys were also collected around the boreholes and analyzed for comparisons. Comprehensive analysis revealed the characteristics of the microbial community composition in the crustal fluids. Phylotypes closely related to cultured species, e.g., Alteromonas, Halomonas, Marinobacter, were relatively abundant in some crustal-fluid samples, whereas the phylotypes related to Pelagibacter and the SUP05-group were relatively abundant in the seawater samples. Phylotypes related to other uncultured environmental clones in Alphaproteobacteria and Gammaproteobacteria were relatively abundant in the sand, rock, sulfide mound and chimney samples. Furthermore, comparative analysis with previous studies of the Suiyo Seamount crustal fluids indicates the change in the microbial community composition for three years. Our results provide novel insights into the characteristics of the microbial communities in crustal fluids beneath a deep-sea hydrothermal field.

  12. Meaningful Field Trip in Education of Renewable Energy Technologies

    Directory of Open Access Journals (Sweden)

    Hasan Said Tortop

    2013-06-01

    Full Text Available Renewable energy sources, in terms of countries‟ obtaining their energy needs from clean and without harming the environment is becoming increasingly important. This situation also requires improving the quality of science education will be given in this field. In this activity, in a field trip to the center for the renewable energy resources technologies, the application of learning cycle model appropriate for constructivist approach is shown. In the example of solar chimney activity according to 5E model, in elaboration step, students, by using their imagination and creativity, put out recommendations and new designs for the efficiency of the application of solar chimney. It is quite important for educators to follow what kind of acquisitions that students will gain and what kind of changes will occur in their perceptions and attitudes towards renewable energy technologies thanks to this activity. Related documents are in attachments. This activity has been very helpful in the education of young scientists on the field of renewable energy sources technologies.

  13. Spin excitations in hole-overdoped iron-based superconductors

    Science.gov (United States)

    Horigane, K.; Kihou, K.; Fujita, K.; Kajimoto, R.; Ikeuchi, K.; Ji, S.; Akimitsu, J.; Lee, C. H.

    2016-01-01

    Understanding the overall features of magnetic excitation is essential for clarifying the mechanism of Cooper pair formation in iron-based superconductors. In particular, clarifying the relationship between magnetism and superconductivity is a central challenge because magnetism may play a key role in their exotic superconductivity. BaFe2As2 is one of ideal systems for such investigation because its superconductivity can be induced in several ways, allowing a comparative examination. Here we report a study on the spin fluctuations of the hole-overdoped iron-based superconductors Ba1-xKxFe2As2 (x = 0.5 and 1.0; Tc = 36 K and 3.4 K, respectively) over the entire Brillouin zone using inelastic neutron scattering. We find that their spin spectra consist of spin wave and chimney-like dispersions. The chimney-like dispersion can be attributed to the itinerant character of magnetism. The band width of the spin wave-like dispersion is almost constant from the non-doped to optimum-doped region, which is followed by a large reduction in the overdoped region. This suggests that the superconductivity is suppressed by the reduction of magnetic exchange couplings, indicating a strong relationship between magnetism and superconductivity in iron-based superconductors. PMID:27615691

  14. QFLOOD-GT: a program for predicting PWR reflood

    International Nuclear Information System (INIS)

    A description is given of the present version of the QFLOOD-GT program for predicting the reflood stage of a large-break PWR loss-of-coolant accident. QFLOOD-GT has been developed from an earlier forced-reflood program which, using a conduction-controlled model for rewetting speed, gave good agreement with the FLECHT SEASET experiments. This earlier program has been incorporated into QFLOOD-GT as a subroutine called QFLOOD; in addition a downcomer model has been included in order to allow calculation of gravity reflood, and a computational scheme has been devised to simulate the chimney effect (the unequal distribution of inlet flow between hot and cool regions of the core). No quantitative comparisons between QFLOOD-GT predictions and integral-test data have yet been carried out, so the modelling decisions implemented in the program are at this stage unvalidated. Preliminary testing of the program has produced results which are for the most part qualitatively satisfactory. Calculations for indicative PWR conditions suggest that the chimney effect has a significant beneficial effect during PWR reflood, a conclusion in accordance with the findings of the Japanese 2D/3D experiments. (author)

  15. Modeling Approach/Strategy for Corrective Action Unit 97, Yucca Flat and Climax Mine , Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    Janet Willie

    2003-08-01

    The objectives of the UGTA corrective action strategy are to predict the location of the contaminant boundary for each CAU, develop and implement a corrective action, and close each CAU. The process for achieving this strategy includes modeling to define the maximum extent of contaminant transport within a specified time frame. Modeling is a method of forecasting how the hydrogeologic system, including the underground test cavities, will behave over time with the goal of assessing the migration of radionuclides away from the cavities and chimneys. Use of flow and transport models to achieve the objectives of the corrective action strategy is specified in the FFACO. In the Yucca Flat/Climax Mine system, radionuclide migration will be governed by releases from the cavities and chimneys, and transport in alluvial aquifers, fractured and partially fractured volcanic rock aquifers and aquitards, the carbonate aquifers, and in intrusive units. Additional complexity is associated with multiple faults in Yucca Flat and the need to consider reactive transport mechanisms that both reduce and enhance the mobility of radionuclides. A summary of the data and information that form the technical basis for the model is provided in this document.

  16. Low cost passive cooling system for social housing in dry hot climate

    Energy Technology Data Exchange (ETDEWEB)

    Macias, M. [Grupo ABIO, ETSI de Caminos, Catedra de Ingenieria Sanitaria, Ciudad Universitaria, 28040 Madrid (Spain); Gaona, J.A. [Consulter Engineer, Avenida Rosa Chacel 31, 28919 Leganes, Madrid (Spain); Luxan, J.M.; Gomez, Gloria [Architect Designers of the Building, ETSArquitectura, Ciudad Universitaria, 28040 Madrid (Spain)

    2009-09-15

    The low energy approach should be the key concept in any long-term strategy aiming to build sustainability. For Madrid climate, action should be taken to reduce energy demand for heating and cooling in residential buildings. The performance of a passive cooling system was developed as a part of design work for the project of a low cost residential building. The passive cooling systems incorporate a solar chimney and precool the air by using the sanitary area of the building. The natural ventilation is enhanced with the help of the solar chimney and fresh air is cooled down by circulation within the sanitary area. The application of this system to the living rooms of a low cost residential building was evaluated and implemented. This cooling system incorporated to a residential building is the third prototype developed since 1991 by the designers. A model was developed to allow to predict the temperature of the air in the living room. The performance of the passive cooling system was evaluated based on the energy balance for a typical summer day. To reduce the energy demand in winter, a new design and window orientation has been developed and evaluated using DOE-2 simulation tool. The building has been constructed and monitored during 2006-2007. (author)

  17. Reduction of Heat Emission to Surroundings From Improved Wood Burning Stove

    Directory of Open Access Journals (Sweden)

    Zakariya Kaneesamkandi

    2014-12-01

    Full Text Available Apart from emissions and inefficiency, heat generation from wood stoves to the surroundings is another undesirable effect causing health repercussions especially in the small dwellings of tropical regions. The present research addresses this problem. Steady state temperature measurements on the surface of the improved wood burning stove is used to determine this loss in which chimney draft control plays an important role. Experimental results were in good agreement with that of the model simulated using the commercial computational fluid dynamics code. A modified model in which changes were introduced to reduce the radiation and convection losses from the stove to the surrounding regions was simulated. Firstly, the radiation losses from the fire was reduced by reducing the size of fuel supply port. Secondly, a waste heat recovery system was introduced which resulted in lower stove body temperature. This was done by optimizing the use of the draft produced by the chimney.Results of the modified model of the stove showed a reduction of this loss by 12.08%. Stoves currently used under the national project for rural energy development was used for this purpose. Apart from improving the stove efficiency, this development will have a positive impact on the acceptability of the improved wood stove in rural households and also help to further reduce fuel consumption.

  18. Radiological assessment report for the Lansdowne property, 105-107 East Stratford Avenue, Lansdowne, Pennsylvania, October-December 1984

    International Nuclear Information System (INIS)

    Areas with elevated levels of radioactivity were found throughout both residences, as well as on the surrounding property. Contamination was also found in the garage behind the 105 East structure. The 105 East residence had substantially more contamination than the 107 East residence, as was expected. The chimneys, particularly the rear chimney, from the 105 East residence had extensive contamination, indicating that contaminated materials may have been burned at the site. The high background radiation emanating from this residence made it difficult to establish the relatively lower levels of contamination in the 107 East residence. The property surrounding the 105 East residence was found to have substantial contamination scattered throughout, with the highest level occurring in the backyard. The soil surface contamination seemed to drop markedly (but not entirely) at the property lines. The property surrounding 107 East was found to be less contaminated, although the background radiation emanating from the adjoining area made it difficult to establish the degree of surface or near-surface contamination from surface surveys. Subsurface investigation of the soil surrounding the structure indicated that radium contamination was widespread and extended to a depth of eight feet at some locations. There was evidence that some of this contamination extended onto adjoining properties and may have been transported off the site via subsurface migration. Additionally, analysis of samples from access points in the residence sewer system effluent established that the system was contaminated. 3 refs., 26 figs., 13 tabs

  19. Toward clean environment: evaluation of solar electric power technologies using fuzzy logic

    Energy Technology Data Exchange (ETDEWEB)

    Badran, Omar; Abdulhadi, Emad [Al-Balqa Applied University, Mechatronics Engineering Department, Faculty of Engineering Technology, Amman (Jordan); Mamlook, Rustom [College of Computer Engineering and Sciences, Al-kharj University, Department of Computer Engineering, Al-kharj (Saudi Arabia)

    2012-04-15

    The rapid expansion of the use of solar energy power plants worldwide is a subject that is being followed with interest. Fuzzy logic methodology is used for evaluating the solar thermal power technology, it compresses huge amount of data into smaller sets, and it has the ability to decide between different solar technologies on the basis of their benefits and costs. The most often considered solar technologies were parabolic trough, central receiver, dish sterling engine, compact linear Fresnel reflector (CLFR), solar chimney, photovoltaic (PV), and solar pond. The aim of our research is to provide the needed information to make a judgment or a decision of adopting the most preferred solar technology in terms of installation and development using fuzzy set methodology. The criteria of the evaluation were based on different parameters, i.e., power capacity, efficiency, availability, capacity factor, storage capability, cost, maturity, water usage, land usage, and safety. The key barriers and features for each technology on the basis of benefit-to-cost ratios are addressed. The results showed that CLFR was found to be the best choice in terms of research, development, and implementation, followed by parabolic trough technology, then the central receiver technology, dish sterling engine, solar chimney, PV, and solar pond, according to the order of preference. (orig.)

  20. SImulated Dodewaard ASsembly: Developments in loop-design

    Energy Technology Data Exchange (ETDEWEB)

    Graaf, R. van de

    1992-03-01

    A computer program was written to calculate void-fraction, flow rate, system circulation time and pressure drops for SIDAS under natural circulation conditions. In this program the thermohydraulic behaviour of the loop is simulated. Taking into account for the large uncertainty in two-phase frictional pressure drops, the chimney length is calculated, together with the length of the tubes which connect the downcomer at assembly height with the assembly inlet in a roundabout way. Tube diameter is chosen such that the frictional pressure losses are negligible. Using the results, it was decided to construct the chimney `telescopically` (consisting of a fixed part and a movable part) in order to influence the driving force. Calculations of the enthalpy of the condensed vapour flow for various system conditions have shown that it is impractical to use this flow to lower the temperature of the total downcomer flow at the necessary subcooling temperature. It is therefore decided to use the condensor flow only for lowering the total downcomer flow enthalpy at saturation enthalpy and to establish the necessary subcooling separately by cooling of the flow in the connecting tubes. (orig.).

  1. SImulated Dodewaard ASsembly: Developments in loop-design

    International Nuclear Information System (INIS)

    A computer program was written to calculate void-fraction, flow rate, system circulation time and pressure drops for SIDAS under natural circulation conditions. In this program the thermohydraulic behaviour of the loop is simulated. Taking into account for the large uncertainty in two-phase frictional pressure drops, the chimney length is calculated, together with the length of the tubes which connect the downcomer at assembly height with the assembly inlet in a roundabout way. Tube diameter is chosen such that the frictional pressure losses are negligible. Using the results, it was decided to construct the chimney 'telescopically' (consisting of a fixed part and a movable part) in order to influence the driving force. Calculations of the enthalpy of the condensed vapour flow for various system conditions have shown that it is impractical to use this flow to lower the temperature of the total downcomer flow at the necessary subcooling temperature. It is therefore decided to use the condensor flow only for lowering the total downcomer flow enthalpy at saturation enthalpy and to establish the necessary subcooling separately by cooling of the flow in the connecting tubes. (orig.)

  2. A geophysical study of a pockmark in the Nyegga Region, Norwegian Sea

    Energy Technology Data Exchange (ETDEWEB)

    Jose, T.; Minshull, T.; Berndt, C. [National Oceanography Centre, Southampton (United Kingdom); Westbrook, G.; Exley, R. [Birmingham Univ., Birmingham (United Kingdom); Nouze, H.; Ker, S.; Gailler, A. [Ifremer, Brest (France). Dept. of Marine Geosciences

    2008-07-01

    Fluid escape features on the sea floor often indicate the presence of gas hydrate sediments in continental margins. Pockmarks are sea-bed culminations of fluid and gas escape chimneys beneath the sea floor, and are often used to obtain information about fluid flow on continental margins. Fluid escape features of pockmarks in the Nyegga region of the Norwegian margin have shown evidence of an active fluid-flow system. This paper provided details of a high resolution seismic experiment conducted over a 2-month period in 2006. An array of 14 ocean bottom seismometers (OBS) were used to obtain a detailed 3-D image of a pockmark. The study also used shots from surface-towed mini GI guns recorded with the use of a near-surface hydrophone streamer. The study demonstrated the presence of gas hydrates, which were recovered from gravity cores taken less than a meter below the sea floor. Hydrate field stability tests demonstrated that the methane gas escaped through the water-saturated sediments in the chimney without being completely converted into gas hydrates. A 2-D model of P wave data across the pockmark showed an increase in velocity between the sea floor and a gas-charged zone at approximately 300 meters beneath the sea floor. 26 refs., 10 figs.

  3. The origin of collapse features appearing in a migrating parabolic dune along the southern coast of Lake Michigan

    Science.gov (United States)

    Argyilan, Erin P.; Avis, Peter G.; Krekeler, Mark P. S.; Morris, Charles C.

    2015-12-01

    Dune decomposition chimneys are collapse features formed when migrating dunes encroach on a forest and buried trees subsequently decay, leaving a temporarily stable open hole. The recent appearance of holes on the stoss slope of Mount Baldy at the Indiana Dunes National Lakeshore provided an opportunity for study of such features. Mount Baldy is a large parabolic dune that is rapidly migrating onshore over a late Holocene landscape with stabilized relict parabolic dunes that supported oak (Quercus spp.) trees visible on the 1939 aerial photo. Individual holes were mapped to locations on the dune surface that would directly overlie the arm of a buried relict parabolic dune. Analyses of buried trees and surrounding sediment indicated that saprotrophic wood decay fungi continue to actively decompose trees after burial and biomineralization of a calcium-carbonate-rich cement occurs at the contact between organic material and sands. Scanning electron microscopy of the cement showed neoformed authigenic minerals and organic structures consistent in morphology with fungal hyphae. We propose that, within the dune, portions of the decayed trees progressively collapse and infill, and open holes are temporarily stabilized by the calcium-carbonate-rich cement. Further, holes can exist undetected at the surface, covered by a thin veneer of sand. Migrating dune systems are observed in many coastal and inland areas. Ongoing work must address the relative contributions of individual environmental factors on the formation of dune decomposition chimneys, including the biomineralization of cement, sand mineralogy, rate of dune movement, tree species, climate, and the composition of fungal communities.

  4. Analysis and optimization of the heat transfer coefficient of a finned heat exchanger submitted to natural convection; Analise e otimizacao do coeficiente de transferencia de calor de um trocador aletado submetido a conveccao natural

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Alan Carlos Bueno da

    1997-07-01

    A heat transfer (condenser) of a domestic freezer was tested in a vertical channel in order to study the influence of the chimney effect in the optimization of the heat transfer coefficient. The variation of the opening of the channel, position and the heating power of the heat exchanger in the heat transfer coefficient was considered. The influence of the surface emissivity on the heat transfer by thermal radiation was studied with the heat exchanger testes without paint and with black paint. The air velocity entering the channel was measured with a hot wire anemometer. In order to evaluate the chimney effect, the heat exchanger was testes in a open ambient. This situation simulates its operational conditions when installed on the freezer system. The variables collected in the experimental procedures was gathered in the form of dimensionless parameters as Nusselt, Rayleigh, Grashof and Prandtl numbers, and dimensional parameters of the convection. The results showed that the highest heat transfer value occurred when both a specific position and a specific channel opening were used. The experiments pointed out that the radiation contribution must be considered in heat transfer calculations. The conclusions showed that different channel openings can improve the heat transfer coefficient in this heat transfer exchanger. (author)

  5. Spatial distribution of viruses associated with planktonic and attached microbial communities in hydrothermal environments.

    Science.gov (United States)

    Yoshida-Takashima, Yukari; Nunoura, Takuro; Kazama, Hiromi; Noguchi, Takuroh; Inoue, Kazuhiro; Akashi, Hironori; Yamanaka, Toshiro; Toki, Tomohiro; Yamamoto, Masahiro; Furushima, Yasuo; Ueno, Yuichiro; Yamamoto, Hiroyuki; Takai, Ken

    2012-03-01

    Viruses play important roles in marine surface ecosystems, but little is known about viral ecology and virus-mediated processes in deep-sea hydrothermal microbial communities. In this study, we examined virus-like particle (VLP) abundances in planktonic and attached microbial communities, which occur in physical and chemical gradients in both deep and shallow submarine hydrothermal environments (mixing waters between hydrothermal fluids and ambient seawater and dense microbial communities attached to chimney surface areas or macrofaunal bodies and colonies). We found that viruses were widely distributed in a variety of hydrothermal microbial habitats, with the exception of the interior parts of hydrothermal chimney structures. The VLP abundance and VLP-to-prokaryote ratio (VPR) in the planktonic habitats increased as the ratio of hydrothermal fluid to mixing water increased. On the other hand, the VLP abundance in attached microbial communities was significantly and positively correlated with the whole prokaryotic abundance; however, the VPRs were always much lower than those for the surrounding hydrothermal waters. This is the first report to show VLP abundance in the attached microbial communities of submarine hydrothermal environments, which presented VPR values significantly lower than those in planktonic microbial communities reported before. These results suggested that viral lifestyles (e.g., lysogenic prevalence) and virus interactions with prokaryotes are significantly different among the planktonic and attached microbial communities that are developing in the submarine hydrothermal environments. PMID:22210205

  6. Thermal-hydraulics stability of natural circulation BWR under startup. Flashing effects

    International Nuclear Information System (INIS)

    To help achieve the necessary natural circulation flow, a fairly long chimney is installed in a boiling natural circulation reactor like the ESBWR. In such systems, thermal-hydraulic stability during low pressure start-up should be examined while considering the flashing induced by the pressure drop in the channel and the chimney due to gravity head. In this work, a BWR stability analysis code in the frequency domain, named FISTAB (Flashing-Induced STability Analysis for BWR), was developed to address the issue of flashing-induced instability. A thermal-hydraulics non-homogeneous equilibrium model (NHEM) based on a drift flux formulation along with a lumped fuel dynamics model is incorporated in the work. The vapor generation rate is derived from the mixture energy conservation equation while considering the effect of flashing. The functionality of the FISTAB code was confirmed by comparison to experimental results from SIRIUS-N facility at CRIEPI, Japan. Both stationary and perturbation results agree well with the experimental results. (author)

  7. Microbial diversity of a sulfide black smoker in main endeavour hydrothermal vent field, Juan de Fuca Ridge.

    Science.gov (United States)

    Zhou, Huaiyang; Li, Jiangtao; Peng, Xiaotong; Meng, Jun; Wang, Fengping; Ai, Yuncan

    2009-06-01

    Submarine hydrothermal vents are among the least-understood habitats on Earth but have been the intense focus of research in the past 30 years. An active hydrothermal sulfide chimney collected from the Dudley site in the Main Endeavour vent Field (MEF) of Juan de Fuca Ridge was investigated using mineralogical and molecular approaches. Mineral analysis indicated that the chimney was composed mainly of Fe-, Zn-and Cu-rich sulfides. According to phylogenetic analysis, within the Crenarchaeota, clones of the order Desulfurococcales predominated, comprising nearly 50% of archaeal clones. Euryarchaeota were composed mainly of clones belonging to Thermococcales and deep-sea hydrothermal vent Euryarchaeota (DHVE), each of which accounted for about 20% of all clones. Thermophilic or hyperthermophilic physiologies were common to the predominant archaeal groups. More than half of bacterial clones belonged to epsilon-Proteobacteria, which confirmed their prevalence in hydrothermal vent environments. Clones of Proteobacteria (gamma-, delta-, beta-), Cytophaga-Flavobacterium-Bacteroides (CFB) and Deinococcus-Thermus occurred as well. It was remarkable that methanogens and methanotrophs were not detected in our 16S rRNA gene library. Our results indicated that sulfur-related metabolism, which included sulfur-reducing activity carried out by thermophilic archaea and sulfur-oxidizing by mesophilic bacteria, was common and crucial to the vent ecosystem in Dudley hydrothermal site. PMID:19557339

  8. U and Th Concentration and Isotopic Composition of Hydrothermal Fluids at the Lost City Hydrothermal Field

    Science.gov (United States)

    Ludwig, K. A.; Shen, C.; Cheng, H.; Edwards, R.; Kelley, D. S.; Butterfield, D. A.

    2006-12-01

    Uranium and Th concentration and isotopic composition of hydrothermal fluids at the Lost City Hydrothermal Field (LCHF) were determined using multi-collector inductively coupled plasma mass spectrometry (MC-ICP- MS). The LCHF is an off-axis, serpentinite-hosted hydrothermal system located at 30°N near the Mid- Atlantic Ridge. Carbonate chimneys reaching 60 m in height vent alkaline (pH~10), calcium-rich fluids at 40- 91°C and the towers are home to dense microbial communities. Vent fluid and seawater U and Th concentration and isotopic composition data provide critical information for constraining U-Th chimney ages. The increased sensitivity (1-2%) of MC-ICP-MS combined with an Aridus nebulization system allows the precise measurement of small quantities of sample (~150 ml) with low concentrations (Thorium concentrations of fluids are close to deep seawater values. U and Th isotopic compositions are reported at the permil level. These data may provide new insights into the role of serpentinite-hosted hydrothermal systems in the budgets of U and Th in the ocean. Techniques presented in this study may be applied to other hydrothermal and seep environments.

  9. Towards Determining the Upper Temperature Limits to Life on Earth: An In-situ Sulfide-Microbial Incubator

    Science.gov (United States)

    Kelley, D.; Baross, J.; Delaney, J.; Girguis, P.; Schrenk, M.

    2004-12-01

    Determining the maximum conditions under which life thrives, survives, and expires is critical to understanding how and where life might have evolved on our planet and for investigation of life in extraterrestrial environments. Submarine black smoker systems are optimal sites to study such questions because thermal gradients are extreme and accessible within the chimney walls under high-pressure conditions. Intact cells containing DNA and ribosomes have been observed even within the most extreme environments of sulfide structure walls bounded by 300\\deg C fluids. Membrane lipids from archaea have been detected in sulfide flanges and chimneys where temperatures are believed to be 200-300\\deg C. However, a balanced inquiry into the limits of life must focus on characterization of the actual conditions in a given system that favor reactions necessary to initiate and/or sustain life. At present, in-situ instrumentation of sulfide deposits is the only effective way to gain direct access to these natural high-temperature environments for documentation and experimentation. With this goal in mind, three prototype microbial incubators were developed with funding from the NSF, University of Washington, and the W.M. Keck Foundation. The incubators were deployed in 2003 in the walls of active black smoker chimneys in the Mothra Hydrothermal Field, Endeavour Segment of the Juan de Fuca Ridge. All instruments were successfully recovered in 2004, and one was redeployed for a short time-series experiment. Each 53-cm-long titanium assembly houses 27 temperature sensors that record temperatures from 0 to 500\\deg C within three discrete incubation chambers. Data are logged in a separate housing and inductively coupled links provide access to the data loggers without removal of the instruments. During the initial deployment, data were collected from 189 to 245 days, with up to ˜478° K temperature measurements completed for an individual instrument. Temperatures within the chimney

  10. Application of Crunch-Flow Routines to Constrain Present and Past Carbon Fluxes at Gas-Hydrate Bearing Sites

    Energy Technology Data Exchange (ETDEWEB)

    Torres, Marta

    2014-01-31

    In November 2012, Oregon State University initiated the project entitled: Application of Crunch-Flow routines to constrain present and past carbon fluxes at gas-hydrate bearing sites. Within this project we developed Crunch-Flow based modeling modules that include important biogeochemical processes that need to be considered in gas hydrate environments. Our modules were applied to quantify carbon cycling in present and past systems, using data collected during several DOE-supported drilling expeditions, which include the Cascadia margin in US, Ulleung Basin in South Korea, and several sites drilled offshore India on the Bay of Bengal and Andaman Sea. Specifically, we completed modeling efforts that: 1) Reproduce the compositional and isotopic profiles observed at the eight drilled sites in the Ulleung Basin that constrain and contrast the carbon cycling pathways at chimney (high methane flux) and non-chimney sites (low methane, advective systems); 2) Simulate the Ba record in the sediments to quantify the past dynamics of methane flux in the southern Hydrate Ridge, Cascadia margin; and 3) Provide quantitative estimates of the thickness of individual mass transport deposits (MTDs), time elapsed after the MTD event, rate of sulfate reduction in the MTD, and time required to reach a new steady state at several sites drilled in the Krishna-Godavari (K-G) Basin off India. In addition we developed a hybrid model scheme by coupling a home-made MATLAB code with CrunchFlow to address the methane transport and chloride enrichment at the Ulleung Basins chimney sites, and contributed the modeling component to a study focusing on pore-scale controls on gas hydrate distribution in sediments from the Andaman Sea. These efforts resulted in two manuscripts currently under review, and contributed the modeling component of another pare, also under review. Lessons learned from these efforts are the basis of a mini-workshop to be held at Oregon State University (Feb 2014) to instruct

  11. Gasbuggy Site Assessment and Risk Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-03-01

    The Gasbuggy site is in northern New Mexico in the San Juan Basin, Rio Arriba County (Figure 1-1). The Gasbuggy experiment was designed to evaluate the use of a nuclear detonation to enhance natural gas production from the Pictured Cliffs Formation, a tight, gas-bearing sandstone formation. The 29-kiloton-yield nuclear device was placed in a 17.5-inch wellbore at 4,240 feet (ft) below ground surface (bgs), approximately 40 ft below the Pictured Cliffs/Lewis shale contact, in an attempt to force the cavity/chimney formed by the detonation up into the Pictured Cliffs Sandstone. The test was conducted below the southwest quarter of Section 36, Township 29 North, Range 4 West, New Mexico Principal Meridian. The device was detonated on December 10, 1967, creating a 335-ft-high chimney above the detonation point and a cavity 160 ft in diameter. The gas produced from GB-ER (the emplacement and reentry well) during the post-detonation production tests was radioactive and diluted, primarily by carbon dioxide. After 2 years, the energy content of the gas had recovered to 80 percent of the value of gas in conventionally developed wells in the area. There is currently no technology capable of remediating deep underground nuclear detonation cavities and chimneys. Consequently, the U.S. Department of Energy (DOE) must continue to manage the Gasbuggy site to ensure that no inadvertent intrusion into the residual contamination occurs. DOE has complete control over the 1/4 section (160 acres) containing the shot cavity, and no drilling is permitted on that property. However, oil and gas leases are on the surrounding land. Therefore, the most likely route of intrusion and potential exposure would be through contaminated natural gas or contaminated water migrating into a producing natural gas well outside the immediate vicinity of ground zero. The purpose of this report is to describe the current site conditions and evaluate the potential health risks posed by the most plausible

  12. Investigation into extremely acidic hydrothermal fluids off Kueishan Tao, Taiwan, China

    Institute of Scientific and Technical Information of China (English)

    CHEN Chentung A; WANG Bingjye; HUANG Jungfu; LOU Jiannyuh; KUO Fuwen; TU Yuehyuan; TSAI Hsienshiow

    2005-01-01

    Kueishan Tao (24°51'N, 121 °55′E) is located at a tectonic junction of the fault system extension of Taiwan and the southern rifting end of the Okinawa Trough. A cluster of over 30 vents, at a water depth of about 10~20 m off the eastern tip of the tao emits hydrothermal fluids and volcanic gases such as H2S. A sulfur chimney or mound, formed by condensation of the sulfur contained in the hydrothermal fluid, can usually be seen around the vents. The tallest chimney reaches 6 m. Vents discharging a yellowish fluid have temperatures between 92 and 116 ℃ and flow rates as high as 158 t/h; vents discharging a whitish fluid have lower temperatures of between 48 and 62 ℃ and lower flow rates of about 7.0 t/h. These world-record, breaking low pH (as low as 1.52) fluids are totally different from those found in the black and white-chimneys of the mid-ocean ridges. Magnesium and SiO2 data indicate that these hydrothermal fluids probably originate from a depth of 915~1 350 m below the surface.While the ratios of major ions relative to the sodium of these hydrothermal fluids are quite similar to open ocean water, the ratios of SO4 and chloride to sodium seem to be higher for some of the vents. It is suggested that the volcanic gases contribute SO4 and ohlorine to the fluids, hence increasing their ratios relative to sodium. Some hydrothermal fluids, however, are found to be depleted of the major elements which can have been caused by phase separation. The concentrations of iron and manganese in the fluids are much lower than those found in the mid-ocean ridges, while the aluminium content is higher. Four species of benthos (Xenograpsus testudinatus, a snail, a sea anemone, and a Sipuncala), 1 species of algae (Corallinaceae), and 1 species of fish (Siganus fusescens) were recorded near the hydrothermal vents. A mitoehondria DNA sequence comparison of Xenograpsus testudinatus with 6 other decapod species shows the greatest number of nitrogen base differences in the

  13. RadscanTM 700 : the role of remote gamma-ray imaging in optimising decommissioning and decontamination strategy

    International Nuclear Information System (INIS)

    BNFL Instruments' RadScanTM 700 was developed as a tool to survey gamma radiation remotely in a wide variety of environments. The instrument plays a major role in the development and implementation of an integrated decommissioning and decontamination strategy for contaminated nuclear facilities. Its directional and spectroscopic information provides the user with ready indication of the nature quantity and location of radioactive material present in any given plant. Two applications are described in this paper both of which demonstrate an area of application for the RadScanTM 700. The first application considers the use of the instrument in a decommissioning programme that has been running for over ten years. RadScanTM was deployed within the Pile Chimney of one of the original plutonium production reactors which operated on the Windscale site in the early 1950s. Contour plots were produced that indicated the contamination levels therein. This information indicated the major sources of dose uptake within the chimney. Following corrective action working times within the chimney were able to be doubled and further decommissioning strategy established. The second application summaries events at a facility in the South of England where RadScanTM 700 was used to monitor contamination within a cell previously used for post-irradiation examination of spent nuclear fuel. The instrument was deployed in the cell remotely from where a full survey of contamination levels was made. This identified hot spots within the cell which enabled the decontamination team to develop their plans for further clean-up work. Recent developments to RadScanTM 700 are discussed which significantly enhance the instrument's performance, versatility and quality of generated data. These developments include an improved detection limit the overlaying of the radiometric image on to the video image and the real-time estimating of dose rate from the Field of View (FOV). RadScanTM 700 is now extensively

  14. Endotension: rupture of abdominal aortic aneurysm Endotensão: ruptura de aneurisma de aorta abdominal

    Directory of Open Access Journals (Sweden)

    Alexandre Campos Moraes Amato

    2012-06-01

    Full Text Available Aortic endovascular exclusion technique called 'chimney' consists of placing stents through abdominal aortic visceral branches and a prosthesis that excludes the thoraco-abdominal aneurysm. Stents and an aortic endoprosthesis are placed in the renal arteries. This method is primarily used when open surgery is too risky. The mechanism that provides aneurysm sac increase without the visible presence of endoleaks has not been fully elucidated. The expansion of the aneurysm sac, due to endotension, is difficult to diagnose, even with the use of advanced imaging tests. Its diagnosis is made by exclusion. We present a case of a late complication in a high-risk patient after a 'chimney' endovascular procedure. Following the surgery, the patient presented a ruptured aneurysm sac without a visible endoleak. A second intervention was not feasible due to the high risk of occluding all of the branches, and complicated by previous 'chimney'. Endotension is a possible cause of aneurysm rupture and death.A técnica de exclusão endovascular conhecida como 'chaminé' consiste na colocação de stent em ramos viscerais e de endoprótese excluindo o aneurisma toracoabdominal. São colocados stents revestidos nas artérias renais e uma endoprótese aórtica, que o método utilizado quando a cirurgia aberta tem risco muito alto. O mecanismo que causa a expansão aneurismática sem a presença detectável de vazamento pelos métodos de imagem não está completamente esclarecido. A expansão do saco aneurismático por endotensão é de difícil diagnóstico, mesmo com o uso de técnicas de imagem avançadas, como tomografia computadorizada e eco-Doppler, sendo o diagnóstico por exclusão. Apresenta-se um caso de complicação tardia após o tratamento endovascular pela técnica da 'chaminé'. Após a cirurgia, o paciente apresentou ruptura sem endoleak visível. Outro procedimento endovascular foi impossibilitado pela técnica da 'chaminé', que dificulta novos

  15. Geochemical and Morphological Characteristics of Metalliferous Deposits at the Endeavour Segment, Juan de Fuca Ridge

    Science.gov (United States)

    Hrischeva, E.; Scott, S.

    2005-12-01

    Metalliferous sediments of the Endeavour Segment, Juan de Fuca Ridge originating from fallout of particles from a hydrothermal plume and wasting of sulfide chimneys and their oxidation products, as well as deposits of primary Fe-Si-rich oxyhydroxides, were collected during Keck supported expeditions in 2003 and 2004. The analysis of sediment deposited within 35 m of an actively venting high-temperature chimney at the Main Endeavour Field and containing hydrothermal material derived from a plume fallout indicates that Fe, Cu and Zn settled as sulfides, constituting about 3% of the sediment, and as amorphous phases. The amorphous material is represented by Fe-Si-S phases and black aggregates of variable Fe-Mn-Si-S-P-Ca-Mg-Cu-Zn composition. The association of the amorphous material with biogenic debris and bacteria suggests that microorganisms have enhanced the scavenging of the metals and their settlement near the vents. Fine-grained sulfides, barite and other mineral particles may have been deposited near the vents as zooplankton fecal pellets. Barite and Fe-Mn oxyhydroxides are the hydrothermal phases in the sediments along 1.8 km of the axial valley. The sediments also contain Fe-rich montmorillonite of authigenic origin, illite, chlorite, quartz, feldspar and calcite. The study of a mound of old oxidized sulfides at the Main Endeavour Field shows that patchy accumulations of Fe oxyhydroxides are associated with increased concentrations of Si. It is suggested that the oxidation of sulfides was accompanied by precipitation of primary Fe-Si oxyhydroxides from diffuse low-temperature sources. At the Mothra Field, low-temperature solutions have deposited amorphous Fe-Si-Mn oxyhydroxides containing minor Ca, P, Mg, S, Zn and Cu as well as amorphous material of Fe-Mn-Si-S-P-Zn-Pb composition that are found as an external crust on the wall of an extinct chimney. In the oxyhydroxide deposits, the amorphous material is associated with a variety of mineralized

  16. Physical controls on mixing and transport within rising submarine hydrothermal plumes: A numerical simulation study

    Science.gov (United States)

    Jiang, Houshuo; Breier, John A.

    2014-10-01

    A computational fluid dynamics (CFD) model was developed to simulate the turbulent flow and species transport of deep-sea high temperature hydrothermal plumes. The model solves numerically the density weighted unsteady Reynolds-averaged Navier-Stokes equations and energy equation and the species transport equation. Turbulent entrainment and mixing is modeled by a k-ε turbulence closure model. The CFD model explicitly considers realistic vent chimney geometry, vent exit fluid temperature and velocity, and background stratification. The model uses field measurements as model inputs and has been validated by field data. These measurements and data, including vent temperature and plume physical structure, were made in the ABE hydrothermal field of the Eastern Lau Spreading Center. A parametric sensitivity study based on this CFD model was conducted to determine the relative importance of vent exit velocity, background stratification, and chimney height on the mixing of vent fluid and seawater. The CFD model was also used to derive several important scalings that are relevant to understanding plume impact on the ocean. These scalings include maximum plume rise height, neutrally buoyant plume height, maximum plume induced turbulent diffusivity, and total plume vertically transported water mass flux. These scaling relationships can be used for constructing simplified 1-dimensional models of geochemistry and microbial activity in hydrothermal plumes. Simulation results show that the classical entrainment assumptions, typically invoked to describe hydrothermal plume transport, only apply up to the vertical level of ~0.6 times the maximum plume rise height. Below that level, the entrainment coefficient remains relatively constant (~0.15). Above that level, the plume flow consists of a pronounced lateral spreading flow, two branches of inward flow immediately above and below the lateral spreading, and recirculation flanking the plume cap region. Both turbulent kinetic energy

  17. Damage and Shaking Intensity in the M5.7 Canyondam Earthquake

    Science.gov (United States)

    Boatwright, J.; Chapman, K.; Gold, M. B.; Hardebeck, J. L.

    2013-12-01

    An M5.7 earthquake occurred southeast of Lake Almanor, CA, at 8:47 PM on May 23, 2013. Double-difference relocations of the main shock and aftershocks indicate that the earthquake nucleated at 11 km depth and ruptured up dip on a fault striking 292° and dipping 70° to the northeast. The earthquake cracked foundations, broke chimneys, and ruptured plumbing around Lake Almanor. We canvassed communities around the lake and to the south and east for earthquake damage, adding reports from our interviews to the geocoded 'Did You Feel It?' reports and to a set of damage reports collected by the Plumas County Office of Emergency Services. Three communities suffered significant damage. In Lake Almanor West, 14 km and 290° from the hypocenter, one wood-frame house was shifted on its foundation, the cripple wall of another house was racked, and water and gas pipes in five houses were ruptured. This damage indicates the shaking approached MMI 8. In Lake Almanor Country Club, 10 km and 310° from the hypocenter, more than 40 chimneys were cracked, broken, or collapsed, a coupling for the municipal water tank was ruptured, and a 200-foot long fissure opened on a slope facing the lake. This damage indicates shaking between MMI 7 and MMI 8, consistent with the accelerograph recording of PGA = 38% g and PGV = 30 cm/s at the Fire Station in Lake Almanor Country Club. This CSMIP station and a PG&E station on the crest of the Butt Valley Dam obtained the only recordings within 50 km of the epicenter. In Hamilton Branch, 10 km and 345° from the hypocenter, a foundation of a wood-frame house was damaged, and 14 chimneys and a water pipe were broken, indicative of MMI 7 shaking. All three communities are underlain by Tertiary and Quaternary basalts. The communities of Chester, Westwood, and Greenville were less damaged, suffering cracked drywall, broken windows, and objects thrown from shelves. The intensities in the three most strongly damaged communities increase as the azimuth

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

    Science.gov (United States)

    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

  19. Gold-silver-tellurium mineral assemblages in different ore styles of the Southern Urals VHMS deposits

    Science.gov (United States)

    Maslennikov, V. V.; Zaykov, V. V.; Maslennikova, S. P.; Tesalina, S. G.; Herrington, R. J.; Buschmann, B.; Becker, K.; Petersen, S.; Orgeval, J. J.; Leistel, M.

    2003-04-01

    VMS deposits of the South Urals generally show a continuum in degradation and reworking ranging from pristine steep-sided hydrothermal sulphide mounds to deposits dominated by layered strata of clastic sulphides. Four different deposits with varying degrees of degradation in order of increased reworking: (Yaman-Kasy longrightarrow Molodezhnoe longrightarrow Alexandrinskoe longrightarrow Balta-Tau) have been ranged. The influence of sulphide mound destruction and of sea-floor alteration on mineral assemblages was investigated In the pristine Yaman-Kasy sulphide mound gold and silver occur as altaite+tellurium+hessite-stuetzite+sylvanite and later galena+native gold+pyrite assemblages in chalcopyrite+isocubanite-rich linings of former chimney conduits. Chalcopyrite-dominated conduit fragments in clastic ore facies contain native tellurium+gold intergrowths. In the weakly reworked Molodezhnoe deposit gold-silver assemblages only occur in sea-floor altered clastic sulphides on the slope of massive sulphide mounds in bornite- and tennantite-rich ores in association with Cu-Ag sulfides such as jalpaite, mckinstryite, and stromeyerite and rare Au-Ag-tellurides (petzite). The Alexandrinskoe deposit is dominated by clastic ores and here native gold and rare hessite occur together with galena in tennantite-sphalerite-dominated veins of the footwall as well as in drusy sphalerite forming conduits of vent chimneys. An assemblage of electrum+galena+tennantite was observed in secondary chalcopyrite in the outer walls of chimneys. Native gold+stromeyerite are common in bornite-rich clastic sulphides while an assemblage of Ag-sulphosalts+electrum is common in barite-rich ores. In the reworked Balta-Tau deposit Ag-sulphosalts+electrum-kustelite occur often together with tennantite+galena+barite banded ores. Gold-silver-telluride mineralisation in these VMS deposits changes with degree of reworking from Au-tellurides, and native gold+galena+pyrite in pristine sulphide mounds to

  20. A Record of the in-Lake and Upland Response to Large Earthquakes, Lake Quinault, Washington

    Science.gov (United States)

    Leithold, E. L.; Wegmann, K. W.; Bohnenstiehl, D. R.; Smith, S. A.

    2014-12-01

    Lake Quinault, located at the foot of the Olympic Mountains in western Washington, has served as a trap for sediment delivered from the steep, landslide-prone terrain of the Upper Quinault River catchment since its formation between 20,000 and 29,000 years ago. High resolution seismic reflection and sedimentological data reveal a record of both the in-lake and upland response to large earthquakes that have impacted the region during that period. The sedimentary infill of Lake Quinault is dominated by deposition during river floods, which delivered both abundant siliciclastic sediment and plant debris to the lake bottom. Minor episodes of soft-sediment deformation at the lake margins are recorded, and based on a preliminary age model, may be related to known earthquakes, including the well documented 1700 AD Cascadia megathrust event. By far the most dramatic event in the middle-late Holocene record of Lake Quinault, however, is the lateral spreading and degassing of sediments on its gentle western slopes during an event ca. 1300 years ago. Abundant gas chimneys are visible in seismic stratigraphic profiles from this part of the lake. Several of these gas chimneys extend from the limit of seismic penetration at 15-20 m depth in the lake bed upward to the lake bottom where they terminate at mounds with evidence for active venting. Most of the gas chimneys, however, end abruptly around 2.5 m beneath the lake floor and are overlain by parallel, continuous reflectors. Piston cores show soft-sediment deformation at this level, and abrupt shifts in density, magnetic susceptibility, flood layer thickness, particle size, color, and inorganic geochemistry. We interpret these shifts to mark the contact between sediments that experienced shaking and degassing during a strong earthquake event and overlying sediments that have not experienced comparable seismicity. The earthquake evidently strongly affected the Upper Quinault River catchment, causing increased sediment input to

  1. Modeling the Growth of Hyperthermophiles in Deep-sea Hydrothermal Diffuse Fluids and Sulfide Deposits

    Science.gov (United States)

    Ver Eecke, H. C.; Oslowski, D. M.; Butterfield, D. A.; Olson, E. J.; Lilley, M. D.; Holden, J. F.

    2009-12-01

    In 2008 and 2009, 534 hydrothermal fluid samples and 5 actively-venting black smoker chimneys were collected using Alvin for correlative microbiological and chemical analyses as part of the Endeavour Segment and Axial Volcano Geochemistry and Ecology Research (EAGER) program. Hyperthermophilic, autotrophic Fe(III) oxide reducers, methanogens, and sulfur-reducing heterotrophs were enriched for at 85 and 95°C using most-probable-number estimates from 28 diffuse fluid and 8 chimney samples. Heterotrophs were the most abundant of the three groups in both diffuse fluids and black-smoker chimneys. Iron reducers were more abundant than methanogens, and more abundant in sulfide-hosted vents than in basalt-hosted vents. Fluid chemistry suggests that there is net biogenic methanogenesis at the Marker 113/62 diffuse vent at Axial Volcano but nowhere else sampled. The growth of hyperthermophilic methanogens and heterotrophs was modeled in the lab using pure cultures. Methanocaldococcus jannaschii grew at 82°C in a 2-liter reactor with continuous gas flow at H2 concentrations between 20 and 225 µM with a H2 km of 100 µM. Correlating H2 end-member mixing curves from vent fluids and seawater with our laboratory modeling study suggests that H2 concentrations are limiting for Methanocaldococcus growth at most Mothra, Main Field, and High Rise vent sites at Endeavour but sufficient to support growth at some Axial Volcano vents. Therefore, hyperthermophilic methanogens may depend on H2 syntrophy at low H2 sites. Twenty-one pure hyperthermophilic heterotroph strains each grew on α-1,4 and β-1,4 linked sugars and polypeptides with concomitant H2 production. The H2 production rate (cell-1 doubling-1) for Pyrococcus furiosus at 95°C without sulfur was 29 fmol, 36 fmol, and 53 fmol for growth on α-1,4 sugars, β-1,4 sugars, and peptides, respectively. The CH4 production rate for M. jannaschii was 390 fmol cell-1 doubling-1; therefore, we estimate that it would take approximately

  2. Dust pollution of the atmosphere in the vicinity of coal-fired power plant (Omsk City, Russia)

    Science.gov (United States)

    Talovskaya, Anna V.; Raputa, Vladimir F.; Litay, Victoriya V.; Yazikov, Egor G.; Yaroslavtseva, Tatyana V.; Mikhailova, Kseniya Y.; Parygina, Irina A.; Lonchakova, Anna D.; Tretykova, Mariya I.

    2015-11-01

    The article shows the results of dust pollution level of air in the vicinity of coal-fired power plant of Omsk city on the base of study snow cover pollution. The samples were collected west-, east- and northeastwards at a distance of 0,75-6 km from the chimney for range-finding of dust emission transfer. The research findings have shown the dust load changes from 53 till 343 mg•(m2·day)-1 in the vicinity of power plant. The ultimate dust load was detected at a distance of 3-3,5 km. On the basis of asymptotics of equation solution for impurity transfer, we have made numerical analysis of dust load rate. With the usage of ground-based facilities and satellites we have determined the wind shifts in the atmospheric boundary layer have a significant impact on the field forming of long-term dustfall.

  3. ‘Working from home: the life and art of Giovanni Baratta’: Francesco Freddolini, Giovanni Baratta 1670-1747. Scultura e industria del marmo tra la Toscana e le corti d’Europa, LermArte documenti 10, Rome: “L’Erma” di Bretschneider, 2013

    Directory of Open Access Journals (Sweden)

    Jennifer Montagu

    2014-12-01

    Full Text Available This monograph describes the life and work of a major marble sculptor who, after his initial training and a period of work in Florence, returned to his native city of Carrara. There he developed the family workshop, where he was able to control the making of marble sculpture from the quarries through the transportation by ship to the installation. With the aid of many assistants, including his brothers and cousins who were also sculptors, he produced not only figurative sculpture but ornamental marble doorways, chimney-pieces, and columns with their bases and capitals. He had gained the patronage of the king of Denmark and the Duke of Marlborough, Madama Reale in Turin, and (through his friendship with Filippo Juvarra the king of Spain, but he seldom moved from his home, preferring to export his sculpture to many cities in Italy and abroad.

  4. {sup 29}Si-NMR study of the absorbent for flue gas desulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Hattori, Hideshi; Kanuka, Nariyasu; Kanai, Ryu-ichi [Hokkaido Univ., Sapporo (Japan)

    1995-12-31

    The flue gas from a coal fired boiler contains a high concentration of SO{sub 2} which should be removed before emitted from a chimney for protection of environment from pollution. A wet desulfurization system is commonly adopted for flue gas desulfurization (FGD), and exhibits a high utilization efficiency of Ca component in the absorbent, but needs a large amount of water. As dry FDD systems, a duct injection and a slurry spraying are adopted. The efficiency, however, is not so high as compared to a wet FGD system. Recently, the SO{sub 2} absorbent which exhibits a high utilization efficiency of Ca component in a dry FGD process was prepared from a coal fly-ash, Ca(OH){sub 2}, and CaSO{sub 4} by hydrothermal reaction. In this project, we studied the structural changes of the absorbent during the hydrothermal reation and sulfur dioxide absorption by silicon 29-MASNMR.

  5. Measurement of biocarbon in flue gases using 14C

    Energy Technology Data Exchange (ETDEWEB)

    Haemaelaeinen, K.M.; Jungner, H.; Antson, O.; Rasanen, J.; Tormonen, K.; Roine, J. [University of Helsinki, Helsinki (Finland). Radiocarbon Dating Laboratory

    2007-07-01

    A preliminary investigation of the biocarbon fraction in carbon dioxide emissions of power plants using both fossil- and biobased fuels is presented. Calculation of the biocarbon fraction is based on radiocarbon content measured in power plant flue gases. Samples were collected directly from the chimneys into plastic sampling bags. The C-14 content in CO{sub 2} was measured by accelerator mass spectrometry (AMS). Flue gases from power plants that use natural gas, coal, wood chips, bark, plywood residue, sludge from the pulp factory, peat, and recovered fuel were measured. Among the selected plants, there was one that used only fossil fuel and one that used only biofuel; the other investigated plants burned mixtures of fuels. The results show that C-14 measurement provides the possibility to determine the ratio of bio and fossil fuel burned in power plants.

  6. Sri Lanka Pilot Study to Examine Respiratory Health Effects and Personal PM2.5 Exposures from Cooking Indoors

    Science.gov (United States)

    Phillips, Michael J.; Smith, Emily A.; Mosquin, Paul L.; Chartier, Ryan; Nandasena, Sumal; Bronstein, Katherine; Elledge, Myles F.; Thornburg, Vanessa; Thornburg, Jonathan; Brown, Linda M.

    2016-01-01

    A pilot study of indoor air pollution produced by biomass cookstoves was conducted in 53 homes in Sri Lanka to assess respiratory conditions associated with stove type (“Anagi” or “Traditional”), kitchen characteristics (e.g., presence of a chimney in the home, indoor cooking area), and concentrations of personal and indoor particulate matter less than 2.5 micrometers in diameter (PM2.5). Each primary cook reported respiratory conditions for herself (cough, phlegm, wheeze, or asthma) and for children (wheeze or asthma) living in her household. For cooks, the presence of at least one respiratory condition was significantly associated with 48-h log-transformed mean personal PM2.5 concentration (PR = 1.35; p PM2.5 concentration (PR = 1.51; p = 0.014). PMID:27527203

  7. Geology of the Alarcón Rise Based on 1-m Resolution Bathymetry and ROV Observations and Sampling

    Science.gov (United States)

    Clague, D. A.; Caress, D. W.; Lundsten, L.; Martin, J. F.; Paduan, J. B.; Portner, R. A.; Bowles, J. A.; Castillo, P. R.; Dreyer, B. M.; Guardado-France, R.; Nieves-Cardoso, C.; Rivera-Huerta, H.; Santa Rosa-del Rio, M.; Spelz-Madero, R.

    2012-12-01

    Alarcón Rise is a ~50 km-long segment of the northernmost East Pacific Rise, bounded on the north and south by the Pescadero and Tamayo Fracture Zones. In April 2012, the MBARI AUV D. Allan B. completed a 1.5-3.1-km wide bathymetric map along the neovolcanic zone between the two fracture zones during 10 surveys. A single AUV survey was also completed on Alarcón Seamount, a near-ridge seamount with 4 offset calderas. Bathymetric data have 1 m lateral and 0.2 m vertical resolution. The maps guided 8 dives of the ROV Doc Ricketts on the ridge and 1 on the seamount. The morphology of the rise changes dramatically along strike and includes an inflated zone, centered ~14 km from the southern end, paved by a young sheet flow erupted from an 8-km-long en echelon fissure system. A young flat-topped volcano and an older shield volcano occur near the center of the ridge segment. Areas nearer the fracture zones are mainly pillow mounds and ridges, some strongly cut by faults and fissures, but others have few structural disruptions. More than 150 of the 194 lava samples recovered from the neovolcanic zone are aphyric to plagioclase-phyric to ultraphyric N-MORB with glass MgO ranging up to 8.5%. The basal cm from 87 short cores contain common limu o Pele and adequate foramifers to provide minimum radiocarbon ages for the underlying lava flows. A rugged lava dome of rhyolite (based on glass compositions) is surrounded by large pillow flows of dacite, centered ~8 km from the north end of the Rise. Pillow flows are steeply uptilted for 2-3 km north and south of the dome, possibly reflecting intrusion of viscous rhyolitic dikes along strike. Near the southern end of this deformed zone, an andesite flow crops out in a fault scarp. Mapping data also reveal the presence of about 110 apparent hydrothermal chimney structures as tall as 18 m, scattered along roughly the central half of the Rise. Subsequent ROV dives observed 70 of these structures and found active venting at 22 of them

  8. Development of centrifuge modeling for evaluating the mechanisms of collapse above underground openings

    International Nuclear Information System (INIS)

    Improved prediction of surface collapse above an underground cavity is important in many LLNL programs, including Nuclear Test. To improve the predictive capability, LLNL must better understand the mechanisms involved in the process of collapse. The research aims to develop the centrifuge technique for modeling mechanisms of underground collapse in soil. The authors will also evaluate the adequacy of existing constitutive or flow models of soils for modeling underground collapse. During FY 86, using the centrifuge at University of California, Davis, the authors developed the basic centrifugal modeling technique, conducted experiments, and modeled the process on a computer. In FY 87, they continued to develop the experimental method and analyze results. Results to date have shown that the model dimensions are not necessarily the critical dimensions (i.e., those determining the adequacy of the model). Rather, the critical dimension is the diameter of the chimney above the opening that develops during collapse

  9. Observations on the effects of some air pollutants on Zea mays leaf tissue

    Energy Technology Data Exchange (ETDEWEB)

    Cireli, B.

    1976-01-01

    The effects of pollutants contained in factory chimney gases of a cement factory on corn seedlings were studied. Plants exposed to pollutants showed growth inhibition and appeared lighter green than control plants. Under the light microscope, large intercellular areas were observed between atypical epidermal, palisade, and spongy cells. Contents of palisade and spongy parenchyma cells were accumulated at certain regions of the cell and chloroplasts changed in shape. Electron microscopic examination of control plants showed mesophyll cells with normal ultrastructure. In the gas exposed plants, breaking of the cell wall at certain points was observed as well as cytoplasm accumulation at certain regions of the cell and occurrence of large vacuolar structures within the cytoplasm. It may be concluded that air pollutants, affecting metabolic activities within the cell, give rise to anatomical and cytological modifications in the palisade parenchyma. 21 references, 5 figures.

  10. Pengembangan Tungku Gasifikasi Arang Biomassa Tipe Natural Draft Gasification Berdasarkan Analisis Computational Fluid Dynamics (CFD

    Directory of Open Access Journals (Sweden)

    Erlanda Augupta Pane

    2014-10-01

    Full Text Available A biomass stove based on natural draft gasification (NDG has been developed in a previous study (Nelwa, et al. 2013 by using simulation based on heat transfer and equilibrium modeling. In this study, a CFD simulation was performed in order to analyze the effect of chimney height, and inlet hole diameter of the stove to the performance of the stove. The results of simulation showed that power produced by stove was between 1863.9 J/s until 2585.7 J/s, and its gasification efficiency was 67.11%. The results of simulation also showed that charcoal gasification produces combustible gases (CO, CH4, and H2 at the bottom and the center of stove, and then they were oxidized by secondary air at the top of stove. This oxidation reaction produces sufficient heat energy which can be used for cooking process.

  11. Environment pollution with aluminium around a coalburning electric power plant

    International Nuclear Information System (INIS)

    The experiments were carried out from November 1991 till November 1993 on the area surrounding an electric power plant within the circle of 20 km diameter and five geographical directions (N, S, SE, E, W). The results presented in this paper have indicated the threats caused by emissions of the power plant ashes and dusts. Mean aluminium content in soil has been multiply surpassed on the area studied. This must have as impact on fauna and flora. The distribution and intensity of pollution is determined first of all by the distance from the emitters and direction of prevailing winds. A part of aluminium contained in water soluble compounds can be distributed on large areas, what adds a lot to the threat to animals. That is why high chimneys do not solve the problem of pollution around big industrial plants. (author)

  12. Body-Centered Orthorhombic C_{16}: A Novel Topological Node-Line Semimetal.

    Science.gov (United States)

    Wang, Jian-Tao; Weng, Hongming; Nie, Simin; Fang, Zhong; Kawazoe, Yoshiyuki; Chen, Changfeng

    2016-05-13

    We identify by ab initio calculations a novel topological semimetal carbon phase in all-sp^{2} bonding networks with a 16-atom body-centered orthorhombic unit cell, termed bco-C_{16}. Total-energy calculations show that bco-C_{16} is comparable to solid fcc-C_{60} in energetic stability, and phonon and molecular dynamics simulations confirm its dynamical stability. This all-sp^{2} carbon allotrope can be regarded as a three-dimensional modification of graphite, and its simulated x-ray diffraction (XRD) pattern matches well a previously unexplained diffraction peak in measured XRD spectra of detonation and chimney soot, indicating its presence in the specimen. Electronic band structure calculations reveal that bco-C_{16} is a topological node-line semimetal with a single nodal ring. These findings establish a novel carbon phase with intriguing structural and electronic properties of fundamental significance and practical interest. PMID:27232027

  13. Evaluation of Efficiency in Steam Generator of C3 Power Plant at Cap Des Biches in Dakar

    Directory of Open Access Journals (Sweden)

    A. Kane

    2012-07-01

    Full Text Available The aim of the present study is to determine the efficiency of the power plant boiler steam C3 Cape deer and to evaluate the impact of it. We chose to calculate the return by the empirical formula of Martin which is based on two important parameters which are the temperature at the exit of the chimney and the ambient temperature. The calculation of these efficiencies allowed us to make comparative studies with data from the manufacturer and we have detected anomalies. On this basis we made a number of recommendations for improvement of the groups in normal, the application will lead to an optimization of the real exploitation of groups and a performance improvement. We gave various reasons for poor performance of steam generators and recommendations that can be used both in production efficiency on compliance with operating instructions. Solutions have been proposed after diagnosis with particular emphasis on compliance with operating instructions and maintenance schedule.

  14. Monitoring of I-131 after Fukushima nuclear power plant disaster and a correction of contribution of I-131 in the discharges of Slovenske elektrarne, Bohunice nuclear power plant

    International Nuclear Information System (INIS)

    After the earthquake and subsequent tsunami in March 2011 Fukushima nuclear power reactors in Japan were damaged. As a result of damage of reactors escaped into air iodine radioactive isotopes which were dispersed by air masses over Europe and Slovakia. Isotope I-131 was identified in samples of the atmosphere and the abstraction of Radiation Control SE EBO. The air from the atmosphere contaminated with isotopes of iodine from the Fukushima ventilation systems that do not contain iodine filters, sucked into the interior of the controlled area, then released in organised way and then measured in the ventilation chimneys of EBO NPP. The measured values thus entered a balance of radioactive discharges. Drain of I-131 from SE EBO was in that period plus a contribution coming from Fukushima NPP and measured activity I-131 had to be corrected.

  15. Experimental study on the stability characteristics of two-phase flows in parallel boiling channels under natural-circulation conditions

    International Nuclear Information System (INIS)

    Experimental study has been performed to study periodical-boiling instability in parallel channels, which occurs at low heat fluxes and is of concern in the start-up process of an SBWR. Three channels, made of glass tubes to facilitate visual observation, are placed in bulk water and are heated with electric heaters inserted in the channels. Two types of channels of different length are used to investigate the effect of unheated risers or chimney on periodical boiling. Relationship of bubble development and flow instability is also studied. It is found that slug bubbles are usually followed by rapid boiling, which results in high fluctuation of the flow. Refilling of the subcooled water from the top causes bubble condensation. Sometimes rapid condensation occurs and results in crack sounds. The longer channel does not necessarily have better coolability and stability characteristics; the average flow rate is actually lower and fluctuation amplitude is higher compared to those for the shorter channel

  16. On the instability of a modified cup-burner flame in the infrared spectral region

    Directory of Open Access Journals (Sweden)

    Petr Bitala

    2016-03-01

    Full Text Available This study describes the modification of a standardised cup-burner apparatus. The replacement of the original glass chimney is performed by shielding a nitrogen co-flow enabled measurement at a wavelength of 3.9 μm. This modification, together with a special arrangement of the measuring system (spectral filtering, data acquisition and post-processing, permitted the observation of various types of hydrodynamic instabilities, including transition states. The advantages of our arrangement are demonstrated with an ethylene non-premixed flame with high sooting tendency. Two known modes of hydrodynamic instability (varicose and sinuous that occur in buoyant flames were studied and described quantitatively. Based on the intensity of the infrared emissions, we identified and qualitatively described the modes of periodic hydrodynamic instability that are accompanied by flame tip opening, which has not been observed for this type of flame.

  17. Optical Detection of Organic Chemical Biosignatures at Hydrothermal Vents

    Science.gov (United States)

    Conrad, P. G.; Lane, A. L.; Bhartia, R.; Hug, W. H.

    2004-01-01

    We have developed a non-contact, optical life detection instrument that can detect organic chemical biosignatures in a number of different environments, including dry land, shallow aqueous, deep marine or in ice. Hence, the instrument is appropriate as a biosignature survey tool both for Mars exploration or in situ experiments in an ice-covered ocean such as one might wish to explore on Europa. Here, we report the results we obtained on an expedition aboard the Russian oceanographic vessel Akademik Mstislav Keldysh to hydrothermal vent sites in the Pacific Ocean using our life detection instrument MCDUVE, a multichannel, deep ultraviolet excitation fluorescence detector. MCDUVE detected organic material distribution on rocks near the vent, as well as direct detection of organisms, both microbial and microscopic. We also were able to detect organic material issuing directly from vent chimneys, measure the organic signature of the water column as we ascended, and passively observe the emission of light directly from some vents.

  18. Effect of wind turbulence on passive external containment cooling

    International Nuclear Information System (INIS)

    The Westinghouse AP600 nuclear generating plant uses a passive containment cooling system to remove energy released to the containment building following a loss-of-coolant accident or main steam line break. This system uses natural draft air cooling and the evaporation of a water film from the outside of the steel containment shell to transfer heat from the containment vessel to the environment. Tests, performed at the Boundary Layer Wind Tunnel Laboratory at the University of Western Ontario, were designed to test the aerodynamic response of air flow past the AP600 containment under a variety of conditions. It is seen that the model-to-full-scale aerodynamic response is insensitive to model size in the range tested. The effect of the wind-induced, oscillating inlet-minus-chimney pressures (with a near zero mean) is to slightly increase heat removal rates from the containment atmosphere and, hence, slightly decrease the calculated containment pressures for the LOCA

  19. Is high-pressure water the cradle of life?

    Energy Technology Data Exchange (ETDEWEB)

    Bassez, Marie-Paule [Universite de Strasbourg-3, Departement Chimie, 72 route du Rhin, 67400 Illkirch (France)

    2003-06-25

    Several theories have been proposed for the synthesis of prebiotic molecules. This letter shows that the structure of supercritical water, or high-pressure water, could trigger prebiotic synthesis and the origin of life deep in the oceans, in hydrothermal vent systems. Dimer geometries of high-pressure water may have a point of symmetry and a zero dipole moment. Consequently, simple apolar molecules found in submarine hydrothermal vent systems will dissolve in the apolar environment provided by the apolar form of the water dimer. Apolar water could be the medium which helps precursor molecules to concentrate and react more efficiently. The formation of prebiotic molecules could thus be linked to the structure of the water inside chimney nanochannels and cavities where hydrothermal piezochemistry and shock wave chemistry could occur. (letter to the editor)

  20. Microvasculature in the terminal air spaces of the lungs of the Baird's beaked whale (Berardius bairdii).

    Science.gov (United States)

    Ninomiya, Hiroyoshi; Inomata, Tomo; Shirouzu, Hiroshi

    2004-12-01

    Lungs were obtained from five adult Baird's beaked whales (Berardius bairdii) and examined by means of light microscopy and scanning electron microscopy of corrosion casts. The alveolar septa of these whales are thick with a connective tissue core and a bi-layer capillary bed. A double capillary network is regularly found in the alveolar duct and alveolar septa. Occasionally, septa adjacent to alveoli and alveoli themselves show only a single capillary layer. The distance between the two capillary layers has a tendency to decrease toward the end of airspaces, suggesting an end result of capillary fusion. Vascular replicas of venous vessels have annular furrows at regular intervals of 50 to 100 microm, which are caused by focal aggregations of collagen fibers circularly oriented and located immediately underneath the endothelium. The first valves appear in the collecting venules gathering alveolar capillaries. These valves are quite characteristic of flap-, funnel-and/or chimney like structures.

  1. Radiological assessment in case of an incident at the hot cells clean-up

    Directory of Open Access Journals (Sweden)

    Dragolici Cristian A.

    2014-01-01

    Full Text Available The clean-up and decontamination of the hot cells will be performed in the second phase of the WWR-S research reactor decommissioning. Identification of possible incidents or accidents is the key element in radiological assessment and prevention. As major incident it was considered a fire burst that occurred during the progress of the clean-up operations. The postulated incident has, as a consequence, thick smoke generation from the burned radioactive material and the dispersion of this material in the environment through the technological ventilation system and the evacuation chimney. From the performed analysis it can be seen that in the case of an incident to the reactor hot cells, an operator engaged in intervention operations could take an effective dose of 5.29 Sv per event, coming from both external and internal exposure. Such an incident, if it happens, would be classified of level 3 on the INES scale.

  2. Transitional dispersive scenarios driven by mesoscale flows on complex terrain under strong dry convective conditions

    Directory of Open Access Journals (Sweden)

    J. L. Palau

    2009-01-01

    Full Text Available By experimentation and modelling, this paper analyses the atmospheric dispersion of the SO2 emissions from a power plant on complex terrain under strong convective conditions, describing the main dispersion features as an ensemble of "stationary dispersive scenarios" and reformulating some "classical" dispersive concepts to deal with the systematically monitored summer dispersive scenarios in inland Spain. The results and discussions presented arise from a statistically representative study of the physical processes associated with the multimodal distribution of pollutants aloft and around a 343-m-tall chimney under strong dry convective conditions in the Iberian Peninsula. This paper analyses the importance of the identification and physical implications of transitional periods for air quality applications. The indetermination of a transversal plume to the preferred transport direction during these transitional periods implies a small (or null physical significance of the classical definition of horizontal standard deviation of the concentration distribution.

  3. Spatial distribution of microbial communities in the shallow submarine alkaline hydrothermal field of the Prony Bay, New Caledonia.

    Science.gov (United States)

    Quéméneur, Marianne; Bes, Méline; Postec, Anne; Mei, Nan; Hamelin, Jérôme; Monnin, Christophe; Chavagnac, Valérie; Payri, Claude; Pelletier, Bernard; Guentas-Dombrowsky, Linda; Gérard, Martine; Pisapia, Céline; Gérard, Emmanuelle; Ménez, Bénédicte; Ollivier, Bernard; Erauso, Gaël

    2014-12-01

    The shallow submarine hydrothermal field of the Prony Bay (New Caledonia) discharges hydrogen- and methane-rich fluids with low salinity, temperature (microbial community structure, abundance and diversity depending on the location, water depth, and structure of the carbonate chimneys. The low archaeal diversity was dominated by few uncultured Methanosarcinales similar to those found in other serpentinization-driven submarine and subterrestrial ecosystems (e.g. Lost City, The Cedars). The most abundant and diverse bacterial communities were mainly composed of Chloroflexi, Deinococcus-Thermus, Firmicutes and Proteobacteria. Functional gene analysis revealed similar abundance and diversity of both Methanosarcinales methanoarchaea, and Desulfovibrionales and Desulfobacterales sulfate-reducers in the studied sites. Molecular studies suggest that redox reactions involving hydrogen, methane and sulfur compounds (e.g. sulfate) are the energy driving forces of the microbial communities inhabiting the Prony hydrothermal system.

  4. Solar building study. Summary report. Macdonald Road, Stornoway, Isle of Lewis

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    Few of the buildings studied in the course of the Energy Performance Assessments project have such a strong foundation in solar energy theory as does the house at MacDonald Road, Stornoway. This evaluation has shown the theory to be essentially correct and that there is potential for passive solar design in high latitudes of the UK. That the building investigated has failed to realise these benefits must in a large part be attributed to the insensitivity of its heating system to solar gains. The house design is otherwise believed to be capable of utilising passive solar gains well, and the sunspace was shown to be a valuable buffer against heat loss. Appraising the measured fuel consumption is complicated by the chimney losses associated with the traditional Hebridean open fire, the occupants` practice of keeping the fire lit all through the year to heat domestic hot water, and the low average house temperatures achieved. (author)

  5. Thermophilic Sulfate Reduction in Hydrothermal Sediment of Lake Tanganyika, East-Africa

    DEFF Research Database (Denmark)

    ELSGAARD, L.; PRIEUR, D.; MUKWAYA, GM;

    1994-01-01

    In environments with temperatures above 60 degrees C, thermophilic prokaryotes are the only metabolically active life-forms. By using the (SO42-)-S-35 tracer technique, we studied the activity of sulfate-reducing microorganisms (SRM) in hot sediment from a hydrothermal vent site in the northern...... population of SRM in the hydrothermal sediment. Thermophilic sulfate reduction had a pH optimum of about 7 and was completely inhibited at pH 8.8 to 9.2. SRM could be enriched from hydrothermal chimney and sediment samples at 60 and 75 degrees C. In lactate-grown enrichments, sulfide production occurred...... at up to 70 and 75 degrees C, with optima at 63 and 71 degrees C, respectively. Several sporulating thermophilic enrichments were morphologically similar to Desulfotomaculum spp. Dissimilatory sulfate reduction in the studied hydrothermal area of Lake Tanganyika apparently has an upper temperature limit...

  6. Metal-nanotube composites as radiation resistant materials

    Science.gov (United States)

    González, Rafael I.; Valencia, Felipe; Mella, José; van Duin, Adri C. T.; So, Kang Pyo; Li, Ju; Kiwi, Miguel; Bringa, Eduardo M.

    2016-07-01

    The improvement of radiation resistance in nanocomposite materials is investigated by means of classical reactive molecular dynamics simulations. In particular, we study the influence of carbon nanotubes (CNTs) in an Ni matrix on the trapping and possible outgassing of He. When CNTs are defect-free, He atoms diffuse alongside CNT walls and, although there is He accumulation at the metal-CNT interface, no He trespassing of the CNT wall is observed, which is consistent with the lack of permeability of a perfect graphene sheet. However, when vacancies are introduced to mimic radiation-induced defects, He atoms penetrate CNTs, which play the role of nano-chimneys, allowing He atoms to escape the damaged zone and reduce bubble formation in the matrix. Consequently, composites made of CNTs inside metals are likely to display improved radiation resistance, particularly when radiation damage is related to swelling and He-induced embrittlement.

  7. Detection of a Large Arc of Ionized Hydrogen Far Above the Cas OB6 Association A Superbubble Blowout into the Galactic Halo?

    CERN Document Server

    Reynolds, R J; Haffner, L M

    2001-01-01

    The Wisconsin H-Alpha Mapper (WHAM) Northern Sky Survey has revealed a loop of H II reaching 1300 pc from the Galactic midplane above the Cas OB6 association in the Perseus sprial arm. This enormous feature surrounds and extends far above the "W4 Chimney" identified by Normandeau et al. and appears to be associated with the star formation activity near the W3/W4/W5 H II region complex. The existence of this ionized structure suggests that past episodes of massive star formation have cleared the H I from an enormous volume above the Perseus arm, allowing Lyman continuum photons from O stars near the Galactic midplane to reach into the halo.

  8. Numerical and Experimental Investigation of Natural Convection in Open-Ended Channels with Application to Building Integrated Photovoltaic (BIPV) Systems

    Science.gov (United States)

    Timchenko, V.; Tkachenko, O. A.; Giroux-Julien, S.; Ménézo, C.

    2015-05-01

    Numerical and experimental investigations of the flow and heat transfer in open-ended channel formed by the double skin façade have been undertaken in order to improve understanding of the phenomena and to apply it to passive cooling of building integrated photovoltaic systems. Both uniform heating and non-uniform heating configurations in which heat sources alternated with unheated zones on both skins were studied. Different periodic and asymmetric heating modes have been considered for the same aspect ratio 1/15 of wall distance to wall height and for periodicity 1/15 and 4/15 of heated/unheated zones and heat input, 220 W/m2. In computational study three dimensional transient LES simulation was carried out. It is shown that in comparison to uniformly heating configuration, non-uniformly heating configuration enhances both convective heat transfer and chimney effect.

  9. Heating with wood. A guide to clean and proper heating; Heizen mit Holz. Ein Ratgeber zum richtigen und sauberen Heizen

    Energy Technology Data Exchange (ETDEWEB)

    Behnke, Anja [Umweltbundesamt, Dessau (Germany); Kemper, Bernd-Michael [Landesanstalt fuer Umwelt, Messungen und Naturschutz Baden-Wuerttemberg (LUBW), Karlsruhe (Germany)

    2013-01-15

    When correctly used, wood is an eco-friendly fuel. By using well-processed wood from local sources in a properly handled modern fireplace, you can enjoy the cosy warmth from your wood-burning stove or boiler without causing significant environmental damage. The environment and your neighbours will be grateful for this. This brochure is intended to give you tips on how to properly operate a wood-based heating system - in technical terms referred to as a small combustion installation. Especially the burning of poor quality wood in old and insufficiently maintained stoves and unfavourable combustion conditions will result in the emission of unnecessarily high levels of greenhouse gases having adverse effects on the climate, and pollutants detrimental to your health. Particularly in urban agglomerations and valleys, the air quality is affected by wood heating systems due to low chimneys. Often, neighbours will feel annoyed.

  10. Development of micro pulse lidar system for atmospheric monitoring

    International Nuclear Information System (INIS)

    A compact small micro pulse lidar system is developed for atmospheric monitoring. The developed system can be operated during 24 hrs for four seasons. The maximum detection distance is 5 km at day time and 10 km at night. Specially, the problem of eye safety is solved by using diode pumped low pulse-energy Nd:YAG laser. Two rotational axis, vertical and horizontal, is chosen for 3D mapping of the atmospheric aerosol. The spatial resolution can be optionally changed from 5 m to 300 m, but time resolution which changes from several sec to several minutes depends on the detection distance and background signal. To analyze the obtained lidar signal, processing software is developed and applied to the lidar signal obtained near the chimney. Vertical lidar signal is also obtained and from this data we can find the thickness and change of cloud. (author)

  11. Anomalous gold, antimony, arsenic, and tungsten in ground water and alluvium around disseminated gold deposits along the Getchell Trend, Humboldt County, Nevada

    Science.gov (United States)

    Grimes, D.J.; Ficklin, W.H.; Meier, A.L.; McHugh, J.B.

    1995-01-01

    Ground-water, alluvium, and bedrock samples were collected from drill holes near the Chimney Creek, Preble, Summer Camp, and Rabbit Creek disseminated gold deposits in northern Nevada. Results of chemical analyses of drill-hole water samples show the presence of hydromorphic dispersion anomalies of Au, As, Sb, and W in the local ground-water systems associated with these deposits. In addition, analysis of sequential dissolution and extraction solutions of drill cuttings of alluvium and bedrock indicate geochemical anomalies of gold and ore-related metals in the overburden at depths corresponding to the location of the present-day water table. This relationship suggests that water-rock reactions around these buried deposits are active. -from Authors

  12. Active control of multi-modal propagation of tonal noise in

    DEFF Research Database (Denmark)

    Laugesen, Søren

    1996-01-01

    The active control of tonal noise propagating in ducts at frequencies where many modes are able to propagate is considered. The final objective of the work reported is to cancel the prominent 450-500 Hz blade passing frequency of the rotary suction fans found in chimney stacks of power stations....... Three sets of experimental results are presented and supported by results from computer simulations. Thus, a number of observations and guidelines for the design of such a control system that so far have been drawn only from theory and simulation studies are discussed based on experimental results from...... laboratory. The study of the full control system, which comprises thirty secondary sources and thirty-two error sensors, has revealed a number of new results, in particular with respect to the positioning of the sources and sensors along the length of the duct. Eventually, a reduction of the radiated power...

  13. Theoretical study of natural ventilation flux in a single span greenhouse

    Directory of Open Access Journals (Sweden)

    Deltour J.

    1998-01-01

    Full Text Available The ventilation flux was calculated for single span greenhouses with single longitudinal roof opening and with bothlongitudinal roof and vertical side wall openings. Thermal buoyancy and wind pressure contributions were separatelyanalysed and then combined for lee-side as well as for windward side ventilation.For the single roof window, the temperatureeffect, proportional to the square root of the temperature difference, becomes negligible when compared to the wind effect,proportional to the wind speed, as soon as this is higher than 1.5 m.s-1.When a vertical side wall opening was added to theroof window, the temperature effect was enhanced by the so called chimney effect, linked with the vertical distance betweenthe two openings, in such a way that it becomes negligible only for an external wind speed higher than 4 m.s-1.

  14. The logical clarinet: numerical optimization of the geometry of woodwind instruments

    CERN Document Server

    Noreland, Daniel; Laloë, Franck; Vergez, Christophe; Guillemain, Philippe; Guilloteau, Alexis

    2012-01-01

    The tone hole geometry of a clarinet is optimized numerically. The instrument is modeled as a network of one dimensional transmission line elements. For each (non-fork) fingering, we first calculate the resonance frequencies of the input impedance peaks, and compare them with the frequencies of a mathematically even chromatic scale (equal temperament). A least square algorithm is then used to minimize the differences and to derive the geometry of the instrument. Various situations are studied, with and without dedicated register hole and/or enlargement of the bore. With a dedicated register hole, the differences can remain less than 10 musical cents throughout the whole usual range of a clarinet. The positions, diameters and lengths of the chimneys vary regularly over the whole length of the instrument, in contrast with usual clarinets. Nevertheless, we recover one usual feature of instruments, namely that gradually larger tone holes occur when the distance to the reed increases. A fully chromatic prototype i...

  15. Sellafield Decommissioning Programme - Update and Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    Lutwyche, P. R.; Challinor, S. F.

    2003-02-24

    The Sellafield site in North West England has over 240 active facilities covering the full nuclear cycle from fuel manufacture through generation, reprocessing and waste treatment. The Sellafield decommissioning programme was formally initiated in the mid 1980s though several plants had been decommissioned prior to this primarily to create space for other plants. Since the initiation of the programme 7 plants have been completely decommissioned, significant progress has been made in a further 16 and a total of 56 major project phases have been completed. This programme update will explain the decommissioning arrangements and strategies and illustrate the progress made on a number of the plants including the Windscale Pile Chimneys, the first reprocessing plan and plutonium plants. These present a range of different challenges and requiring approaches from fully hands on to fully remote. Some of the key lessons learned will be highlighted.

  16. Combustion Quality Estimation in Power Station Boilers using Median Threshold Clustering Algorithms

    Directory of Open Access Journals (Sweden)

    K.Sujatha

    2010-07-01

    Full Text Available The estimation of combustion quality in power station boilers is of great importance in the present scenario as it plays an important role in controlling the air pollution. The harmful gases like NOx and CO from the chimney causes air pollution. The amount of NOx and CO concentration in flue gas can be maintained within admissible limits by analyzing the flame colour. The colour of the flame is affected by combustion quality. When complete combustion takes place the amount these gases at the exit are within tolerance. Hence if the quality of combustion was estimated from the flame using image processing technique, it is possible to minimize the air pollution. This new strategy developed uses median threshold for feature reduction and various clustering algorithms to estimate the quality of combustion.

  17. Structural shell analysis understanding and application

    CERN Document Server

    Blaauwendraad, Johan

    2014-01-01

    The mathematical description of the properties of a shell is much more elaborate than those of beam and plate structures. Therefore many engineers and architects are unacquainted with aspects of shell behaviour and design, and are not familiar with sufficiently reliable shell theories for the different shell types as derived in the middle of the 20th century. Rather than contributing to theory development, this university textbook focuses on architectural and civil engineering schools. Of course, practising professionals will profit from it as well. The book deals with thin elastic shells, in particular with cylindrical, conical and spherical types, and with elliptic and hyperbolic paraboloids. The focus is on roofs, chimneys, pressure vessels and storage tanks. Special attention is paid to edge bending disturbance zones, which is indispensable knowledge in FE meshing. A substantial part of the book results from research efforts in the mid 20th century at Delft University of Technology. As such, it is a valua...

  18. Rethinking Buoyancy, at the Surface and Aloft

    Science.gov (United States)

    Jeevanjee, N.; Romps, D. M.

    2015-12-01

    The Archimedean buoyancy is the standard measure of buoyant acceleration, but fails to account for the back-reaction of the environment on accelerating parcels. For parcels that are wide and/or near the surface, this back-reaction can produce an `effective buoyancy' quite different from the Archimedean one. We quantify these effects by computing exact analytical expressions for the effective buoyancy of idealized buoyant parcels at the surface and aloft. These results depend strongly on both aspect ratio as well as surface proximity, and in particular show that a surface parcel accelerates much slower than the same parcel aloft. We illustrate these effects with large-eddy simulations, and understand them using a view of buoyancy in which vertical accelerations are driven by horizontal hydrostatic pressure gradients, similar to how a chimney works. These analytical formulae may be useful in convective parameterizations, as well as for thinking about the "grey zone" of horizontal resolution in large-scale numerical models.

  19. Risk factors for Campylobacter colonization in Danish broiler flocks, 2010 to 2011

    DEFF Research Database (Denmark)

    Sandberg, M; Sørensen, L L; Steenberg, B;

    2015-01-01

    negative; and litter delivered into the house close to the time of arrival of new chickens vs. storing litter on the farm. Furthermore, the data showed that a vertically based ventilation system (where most of the air is taken into the house through chimneys) constituted a higher risk than a horizontally......The objectives of the two studies presented were to estimate the prevalence of Campylobacter-positive farms and flocks and to acquire updated knowledge about risk factors for the introduction of Campylobacter in Danish broiler flocks. In the first study, from September 2010 to September 2011, there...... were 25 Danish broiler farms visited, and a questionnaire was filled in by a veterinarian/consultant. In the second study, a similar questionnaire was distributed electronically to all Danish broiler farmers (n = 164) that were on record with an email address in the Quality Assurance System in the...

  20. Development of micro pulse lidar system for atmospheric monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Hyung Ki; Song, Kyu Seok; Lee, Jong Min; Lee, Yong Ju; Kim, Duk Hyeon; Nam, Sung Mo; Go, Do Kyung; Yang, Gi Ho; Hong, Kyang He

    1999-12-01

    A compact small micro pulse lidar system is developed for atmospheric monitoring. The developed system can be operated during 24 hrs for four seasons. The maximum detection distance is 5 km at day time and 10 km at night. Specially, the problem of eye safety is solved by using diode pumped low pulse-energy Nd:YAG laser. Two rotational axis, vertical and horizontal, is chosen for 3D mapping of the atmospheric aerosol. The spatial resolution can be optionally changed from 5 m to 300 m, but time resolution which changes from several sec to several minutes depends on the detection distance and background signal. To analyze the obtained lidar signal, processing software is developed and applied to the lidar signal obtained near the chimney. Vertical lidar signal is also obtained and from this data we can find the thickness and change of cloud. (author)

  1. 石灰岩介质中地下核试验熔岩的矿物研究及其形成过程

    Institute of Scientific and Technical Information of China (English)

    蔡华昌; 王道德

    1984-01-01

    The melt rocks produced during an underground nuclear explosion in the limestone medium may be classified into three types in the light of thin-section examinations and chemical compositions. One of them is the carbonate melt rock which is distributed widely and very large in quantities. About 20 kinds of monominerals were identified by X-ray powder and electron microprobe techniques. Some minerals, such as moissanite, brownkillerite, Ca12Ah14O33, etc., are rare or have not yet been discovered in nature. In addition, this paper presents the four stages of formation of the melt rocks, i.e., the vaporization-liquefaction stage, the initial crystallization-cavity stripping stage, the crystallization stage, and the chimney formation-thermal metamorphism stags. Furthermore, preliminary theoretical analysis was carried out of the physico-chemical process of mineral formation.

  2. Oscillating and star-shaped drops levitated by an airflow

    CERN Document Server

    Bouwhuis, Wilco; Peters, Ivo R; Brunet, Philippe; van der Meer, Devaraj; Snoeijer, Jacco H

    2013-01-01

    We investigate the spontaneous oscillations of drops levitated above an air cushion, eventually inducing a breaking of axisymmetry and the appearance of `star drops'. This is strongly reminiscent of the Leidenfrost stars that are observed for drops floating above a hot substrate. The key advantage of this work is that we inject the airflow at a constant rate below the drop, thus eliminating thermal effects and allowing for a better control of the flow rate. We perform experiments with drops of different viscosities and observe stable states, oscillations and chimney instabilities. We find that for a given drop size the instability appears above a critical flow rate, where the latter is largest for small drops. All these observations are reproduced by numerical simulations, where we treat the drop using potential flow and the gas as a viscous lubrication layer. Qualitatively, the onset of instability agrees with the experimental results, although the typical flow rates are too large by a factor 10. Our results...

  3. Social-Economic Criteria about the Application of Shell Foundations

    Directory of Open Access Journals (Sweden)

    Yoermes González Haramboure

    2013-02-01

    Full Text Available TaThis paper provide arguments about the relevance of research and application of shell foundations,from a literature review that sets the theoretical and practical development attained by Cuban civilengineering in this field. It identifies several Cuban buildings with great social and economic importance,where the use of shell foundations helped to reduce the construction cost, and construction difficultiesattributed to its execution were refuted. Are mentioned the main theoretical contributions and studiesthat established equations and calculation methods applied to shells for «tower» structures foundations.By comparison in terms of volumes of materials, costs, volumes of fuel consumed and CO2 emittedinto the atmosphere in cement production, this article concludes on economic and environmentaladvantages of implementing shell foundations with respect to traditional flat base foundations in elevatedtanks type «Güira» and chimneys for sugar industries.

  4. Chemistry. How to adapt and invest in front of the new rules?; Chimie. Comment s`adapter et investir face aux nouvelles regles?

    Energy Technology Data Exchange (ETDEWEB)

    Paules, B. [ELF Atochem, 92 - Puteaux (France)

    1997-12-31

    This paper is a series of transparencies about the experience of Elf Atochem company in the reduction of NO{sub x} emissions from petrochemical plants. The St Auban plant (France) is taken as a first example: description, regulations and NO{sub x} reduction goals, NO{sub x} reduction techniques (non-reheating of the combustion air, modifications on burners, injection of ammonia-compounds in smokes), results of the preliminary study on ammonia-compounds injection, application and principle of regulation. The second example concerns the development of a cogeneration system in the Marseille plant (description of existing installations, the cogeneration installation project, the regulatory context, the gas turbine and its post-combustion system, the dual-fuel system and the pollution regulations: chimney height, limit values of NO{sub x} and dust emissions). (J.S.)

  5. Tackling turbulent flows in engineering

    Energy Technology Data Exchange (ETDEWEB)

    Dewan, Anupam [Indian Institute of Technology Delhi, New Delhi (India). Dept. of Applied Mechanics

    2011-07-01

    The emphasis of this book is on engineering aspects of fluid turbulence. The book explains for example how to tackle turbulence in industrial applications. It is useful to several disciplines, such as, mechanical, civil, chemical, aerospace engineers and also to professors, researchers, beginners, under graduates and post graduates. The following issues are emphasized in the book: - Modeling and computations of engineering flows: The author discusses in detail the quantities of interest for engineering turbulent flows and how to select an appropriate turbulence model; Also, a treatment of the selection of appropriate boundary conditions for the CFD simulations is given. - Modeling of turbulent convective heat transfer: This is encountered in several practical situations. It basically needs discussion on issues of treatment of walls and turbulent heat fluxes. - Modeling of buoyancy driven flows, for example, smoke issuing from chimney, pollutant discharge into water bodies, etc. (orig.)

  6. A deep sea community at the Kebrit brine pool in the Red Sea

    KAUST Repository

    Vestheim, Hege

    2015-02-26

    Approximately 25 deep sea brine pools occur along the mid axis of the Red Sea. These hypersaline, anoxic, and acidic environments have previously been reported to host diverse microbial communities. We visited the Kebrit brine pool in April 2013 and found macrofauna present just above the brine–seawater interface (~1465 m). In particular, inactive sulfur chimneys had associated epifauna of sea anemones, sabellid type polychaetes, and hydroids, and infauna consisting of capitellid polychaetes, gastropods of the genus Laeviphitus (fam. Elachisinidae), and top snails of the family Cocculinidae. The deep Red Sea generally is regarded as extremely poor in benthos. We hypothesize that the periphery along the Kebrit holds increased biomass and biodiversity that are sustained by prokaryotes associated with the brine pool or co-occurring seeps.

  7. Numerical and Experimental Investigation of Natural Convection in Open-Ended Channels with Application to Building Integrated Photovoltaic (BIPV Systems

    Directory of Open Access Journals (Sweden)

    Timchenko V.

    2015-01-01

    Full Text Available Numerical and experimental investigations of the flow and heat transfer in open-ended channel formed by the double skin façade have been undertaken in order to improve understanding of the phenomena and to apply it to passive cooling of building integrated photovoltaic systems. Both uniform heating and non-uniform heating configurations in which heat sources alternated with unheated zones on both skins were studied. Different periodic and asymmetric heating modes have been considered for the same aspect ratio 1/15 of wall distance to wall height and for periodicity 1/15 and 4/15 of heated/unheated zones and heat input, 220 W/m2. In computational study three dimensional transient LES simulation was carried out. It is shown that in comparison to uniformly heating configuration, non-uniformly heating configuration enhances both convective heat transfer and chimney effect.

  8. Solar Radiation Estimation on Building Roofs and Web-Based Solar Cadastre

    Science.gov (United States)

    Agugiaro, G.; Nex, F.; Remondino, F.; De Filippi, R.; Droghetti, S.; Furlanello, C.

    2012-07-01

    The aim of this study is the estimation of solar irradiance on building roofs in complex Alpine landscapes. Very high resolution geometric models of the building roofs are generated by means of advanced automated image matching methods. Models are combined with raster and vector data sources to estimate the incoming solar radiation hitting the roofs. The methodology takes into account for atmospheric effects, site latitude and elevation, slope and aspect of the terrain as well as the effects of shadows cast by surrounding buildings, chimneys, dormers, vegetation and terrain topography. An open source software solution has been developed and applied to a study area located in a mountainous site and containing some 1250 residential, commercial and industrial buildings. The method has been validated by data collected with a pyranometer and results made available through a prototype WebGIS platform.

  9. Elements of an algorithm for optimizing a parameter-structural neural network

    Science.gov (United States)

    Mrówczyńska, Maria

    2016-06-01

    The field of processing information provided by measurement results is one of the most important components of geodetic technologies. The dynamic development of this field improves classic algorithms for numerical calculations in the aspect of analytical solutions that are difficult to achieve. Algorithms based on artificial intelligence in the form of artificial neural networks, including the topology of connections between neurons have become an important instrument connected to the problem of processing and modelling processes. This concept results from the integration of neural networks and parameter optimization methods and makes it possible to avoid the necessity to arbitrarily define the structure of a network. This kind of extension of the training process is exemplified by the algorithm called the Group Method of Data Handling (GMDH), which belongs to the class of evolutionary algorithms. The article presents a GMDH type network, used for modelling deformations of the geometrical axis of a steel chimney during its operation.

  10. Elements of an algorithm for optimizing a parameter-structural neural network

    Directory of Open Access Journals (Sweden)

    Mrówczyńska Maria

    2016-06-01

    Full Text Available The field of processing information provided by measurement results is one of the most important components of geodetic technologies. The dynamic development of this field improves classic algorithms for numerical calculations in the aspect of analytical solutions that are difficult to achieve. Algorithms based on artificial intelligence in the form of artificial neural networks, including the topology of connections between neurons have become an important instrument connected to the problem of processing and modelling processes. This concept results from the integration of neural networks and parameter optimization methods and makes it possible to avoid the necessity to arbitrarily define the structure of a network. This kind of extension of the training process is exemplified by the algorithm called the Group Method of Data Handling (GMDH, which belongs to the class of evolutionary algorithms. The article presents a GMDH type network, used for modelling deformations of the geometrical axis of a steel chimney during its operation.

  11. Analysis of data from the Pericles and reflex experiments using the Codes Trac-PF1/MOD1 and QFLOOD

    International Nuclear Information System (INIS)

    The computer programs TRAC-FP1/MOD1 and QFLOOD have been used to analyse data obtained from two reflood rigs: PERICLES, a 7 - 51 bundle arranged to investigate the chimney effect, and REFLEX, a single heated tube. TRAC produced poor predictions for PERICLES, the calculated temperature history curves at the 2.03 m elevation differing markedly from experiment. TRAC predictions for the REFLEX base case agreed quite well with experiment, but for a second REFLEX test, at higher inlet water flowrate, TRAC greatly overpredicted the quench front speed. QFLOOD also performed badly against PERICLES, quench time being overpredicted by more than 50%. A number of sensitivity studies were carried out in order to establish the source of the error in the modelling. Several possible explanations were investigated, but definite conclusions could not be drawn. QFLOOD predictions for REFLEX were generally satisfactory

  12. Nuclear and health news. iodine 131 Fleurus incident - Belgium

    International Nuclear Information System (INIS)

    On the 25. august 2008, the operator of the institute of radioelements in belgium has informed the federal agency of nuclear control of an abnormal release of iodine 131 by the chimney of the building to environment. This release occurred following a transfer of liquid effluents between tanks. This release lasts several days and the activity released has been estimated to 45 Giga-becquerels. The incident was classified at the level 3 on the INES scale. The production of radioelements was stopped and the consumption of fruits and vegetables from gardens as well as the rainwater was forbidden at five kilometers at the north-east of the installation. On the 30. august analysis were made on grass and milk but no detection of iodine 131 appears. (N.C.)

  13. Air guide device for evaporation burner. Luftleiteinrichtung fuer Verdampfungsbrenner

    Energy Technology Data Exchange (ETDEWEB)

    Pniok, D.; Schattenberg, F.; Gundlach, H.

    1984-02-02

    The invention refers to an evaporation burner preferably for a fuel throughput of up to 1 kg/hour, which is mainly used in mobile units. The aim of the invention is to design the evaporation burner for changing working conditions, such as changing mains voltages, ambient temperatures and chimney resistances. This aim is achieved by an air guide device for supplying and distributing combustion air in the combustion chamber. This air guide device is a tubular body with slots at an angle to the axis, which is covered on one side by a disc at a certain distance. It is situated centrally inside a cylindrical combustion chamber and its length is approximately equal to the width of the evaporation surface.

  14. [Molybdenum as an air pollutant].

    Science.gov (United States)

    Lindner, R; Junker, E; Hoheiser, H

    1990-07-01

    Investigations into the reasons for the retarded growth and discolouration of a small area of a field of rape situated on the outskirts of Vienna revealed higher than normal levels of molybdenum in the soil (up to 430 micrograms/l) and in the water (up to 9.7 mg/l). The source of the pollution was traced to a neighbouring industrial plant that was emitting the metal via the chimney stack. A review of the literature on the toxic effects of molybdenum in general and as an air pollutant in particular is provided. This shows that, in contrast to animals, this effect is relatively small in humans and plants. Nevertheless, the occupation-related inhalation of the metal has been shown to be associated with pneumoconiosis and gout-like symptoms.

  15. Site selection

    International Nuclear Information System (INIS)

    The conditions and criteria for selecting a site for a nuclear weapons test at the Nevada Test Site are summarized. Factors considered are: (1) scheduling of drill rigs, (2) scheduling of site preparation (dirt work, auger hole, surface casing, cementing), (3) schedule of event (when are drill hole data needed), (4) depth range of proposed W.P., (5) geologic structure (faults, Pz contact, etc.), (6) stratigraphy (alluvium, location of Grouse Canyon Tuff, etc.), (7) material properties (particularly montmorillonite and CO2 content), (8) water table depth, (9) potential drilling problems (caving), (10) adjacent collapse craters and chimneys, (11) adjacent expended but uncollapsed sites, (12) adjacent post-shot or other small diameter holes, (13) adjacent stockpile emplacement holes, (14) adjacent planned events (including LANL), (15) projected needs of Test Program for various DOB's and operational separations, and (16) optimal use of NTS real estate

  16. Galactic Worm 123.4-1.5 A Mushroom-shaped HI Cloud

    CERN Document Server

    English, J; Mashchenko, S Y; Irwin, J A; Basu, S; Johnstone, D; English, Jayanne; Mashchenko, Sergey Y; Irwin, Judith A; Basu, Shantanu; Johnstone, Doug

    2000-01-01

    The Dominion Radio Astrophysical Observatory's Synthesis Telescope providesthe highest resolution data (1 arcmin and 0.82 km/s) to date of an HI wormcandidate. Observed as part of the Canadian Galactic Plane Survey,mushroom-shaped GW 123.4-1.5 extends only a few hundred parsecs, contains ~10^5solar masses of neutral hydrogen, and appears unrelated to a conventional shellor chimney structure. Our preliminary Zeus-2d models use a single off-planeexplosion with a modest (~10^{51} ergs) energy input. These generic simulationsgenerate, interior to an expanding outer blast wave, a buoyant cloud whosestructure resembles the morphology of the observed feature. Unlike typicalmodel superbubbles, the stem can be narrow because its width is not governed bythe pressure behind the blast wave nor the disk scale height. Using this typeof approach it should be possible to more accurately model the thin stem andother details of GW 123.4-1.5 in the future.

  17. Simulations of dispersion and deposition of coarse particulate matter

    CERN Document Server

    Cionco, Rodolfo G; Caligaris, Marta G

    2012-01-01

    In order to study the dispersion and deposition of coarse anthropogenic particulate matter (PMc, aerodynamic diameters> 10 mm), a FORTRAN simulator based on the numerical integrator of Bulirsch and Stoer has been developed. It calculates trajectories of particles of several shapes released into the atmosphere under very general conditions. This first version, fully three-dimensional, models the meteorology under neutral stability conditions. The simulations of such pollutants are also important because the standard software (usually originating in the United States Environmental Protection Agency-EPA-) describe only the behavior of PM10 (diameter less than 10 mm). Bulirsch and Stoer integrator of widespread use in astrophysics, is also very fast and accurate for this type of simulations. We present 2D and 3D trajectories in physical space and discuss the final deposition in function of various parameters. PMc simulations results in the range of 50-100 mm and densities of 5.5 g cm-3 emitted from chimneys, indi...

  18. Actinomyces naeslundii in intial dental biofilm formation

    DEFF Research Database (Denmark)

    Dige, Irene; Raarup, Merete Krog; Nyengaard, Jens Randel;

    2009-01-01

    Combined use of Confocal Laser Scanning Microscopy (CLSM) and Fluorescent in situ Hybridization (FISH) offers new opportunities for analysing the spatial relationships and temporal changes of specific members of microbial populations in intact dental biofilms. AIMS: The purpose of this study....... RESULTS: This study confirmed previous work that streptococci are the predominant colonizers of early dental biofilm along with A. naeslundii. There was a notable increase in the total number of bacteria, Streptococcus spp., and A. naeslundii over time with a tendency towards a slower growth rate for A......-layer dental biofilms up to 48 h definitively demonstrated that A. naeslundii preferentially occupied the inner layers. Some A. naeslundii microcolonies extended perpendicularly from the supporting surface surrounded by other bacteria forming chimneys of complex multilayered micro-colonies. CONCLUSIONS...

  19. An automated miniature robotic vehicle inspection system

    International Nuclear Information System (INIS)

    A novel, autonomous reconfigurable robotic inspection system for quantitative NDE mapping is presented. The system consists of a fleet of wireless (802.11g) miniature robotic vehicles, each approximately 175 × 125 × 85 mm with magnetic wheels that enable them to inspect industrial structures such as storage tanks, chimneys and large diameter pipe work. The robots carry one of a number of payloads including a two channel MFL sensor, a 5 MHz dry coupled UT thickness wheel probe and a machine vision camera that images the surface. The system creates an NDE map of the structure overlaying results onto a 3D model in real time. The authors provide an overview of the robot design, data fusion algorithms (positioning and NDE) and visualization software

  20. Evidence of shallow gas in the Queen Charlotte Basin from waveform tomography of seismic reflection data

    Energy Technology Data Exchange (ETDEWEB)

    Takam Takougang, Eric M.; Calvert, Andrew J. [Simon Fraser University (Canada)], email: eta9@sfu.ca

    2011-07-01

    The Geological Survey of Canada (GSC) collected eight seismic reflection lines in 1988 across the Queen Charlotte sedimentary basin of western Canada, which is the largest tertiary basin on the west coast. This work furthers the study of the upper part of the basin by using quantitative imaging of its structure through application of 2-D waveform tomography to the limited offset seismic reflection data. With the help of waveform tomography, seismic reflection data has allowed the identification of pockmark structures and pipe-like gas chimney in the recovered velocity and attenuation models. Overall, there is an excellent match between field data and predicted data. and a good match between the sonic log and a 1-D velocity function derived from the 2-D velocity model. This shows that specific preconditioning of the data and a good inversion strategy make it possible to use waveform tomography of relatively short offset reflection data for the imaging of shallow geological features.

  1. Research on Climate Change and Its Impacts Needs Freedom of Research

    Directory of Open Access Journals (Sweden)

    Nicole Mölders

    2013-12-01

    Full Text Available Climate change captured my interest as a teenager when, at the dining table, my dad talked about potential anthropogenic climate changes. He brought up subjects such as “climate could change if the Siberian Rivers were to be deviated to the South for irrigation of the (semi arid areas of the former Soviet Union”. Other subjects were afforestation in the Sahel to enhance precipitation recycling, deforestation in the Tropics that could have worldwide impacts on climate, the local climate impacts of the Merowe High Dam in its vicinity and downstream, Atlantropa, a new ice age, and the increase in days with sunshine after the introduction of the high-chimney policy in the Rhein-Ruhr area, just to mention a few.

  2. Old bulgarian architecture - an university of solar energy application

    Energy Technology Data Exchange (ETDEWEB)

    Dobrinova, Annie [Bulgarian Solar Energy Society, Sofia (Bulgaria)

    2008-07-01

    The impressing involvement of the ancient Bulgarian houses in the surroundings and their composition reveal nearly all aspects of Solar Energy (SE) and energy efficiency(EE) tools' application. In this paper are concerned (and richly illustrated), namely: direct/indirect gains, thermal mass, convectional loops, sun spaces (atrium case), solar chimney, synthesis exterior/interior; etc. The joint effect is highly convincing in the SE and EE knowledge of ancient anonymous master-builder. The SE conception is obviously always well considered, readable, well planned and its combined effect is not accidental at all. Such investigation could be of great importance for a new meaning (not only in Bulgaria) to History of Architecture. Investigations like this could motivate a future unwritten yet Bioclimatic history of world architecture. (orig.)

  3. Is high-pressure water the cradle of life?

    International Nuclear Information System (INIS)

    Several theories have been proposed for the synthesis of prebiotic molecules. This letter shows that the structure of supercritical water, or high-pressure water, could trigger prebiotic synthesis and the origin of life deep in the oceans, in hydrothermal vent systems. Dimer geometries of high-pressure water may have a point of symmetry and a zero dipole moment. Consequently, simple apolar molecules found in submarine hydrothermal vent systems will dissolve in the apolar environment provided by the apolar form of the water dimer. Apolar water could be the medium which helps precursor molecules to concentrate and react more efficiently. The formation of prebiotic molecules could thus be linked to the structure of the water inside chimney nanochannels and cavities where hydrothermal piezochemistry and shock wave chemistry could occur. (letter to the editor)

  4. The evolution of volcano-hosted geothermal systems based on deep wells from Karaha-Telaga Bodas, Indonesia

    Science.gov (United States)

    Moore, J.N.; Allis, R.G.; Nemcok, M.; Powell, T.S.; Bruton, C.J.; Wannamaker, P.E.; Raharjo, I.B.; Norman, D.I.

    2008-01-01

    Temperature and pressure surveys, fluid samples, and petrologic analyses of rock samples from deep drill holes at the Karaha - Telaga Bodas geothermal field on the volcanic ridge extending northward from Galunggung Volcano, West Java, have provided a unique opportunity to characterize the evolution of an active volcano-hosted geothermal system. Wells up to 3 km in depth have encountered temperatures as high as 353??C and a weakly altered granodiorite that intruded to within 2 to 3 km of the surface. The intrusion is shallowest beneath the southern end of the field where an acid lake overlies a nearly vertical low resistivity structure (<10 ohm-m) defined by magnetotelluric measurements. This structure is interpreted to represent a vapor-dominated chimney that provides a pathway to the surface for magmatic gases. Four distinct hydrothermal mineral assemblages document the evolution of the geothermal system and the transition from liquid- to vapor-dominated conditions. The earliest assemblage represents the initial liquid-dominated system generated during emplacement of the granodiorite between 5910 ?? 76 and 4200 ?? 150 y BP. Tourmaline, biotite, actinolite, epidote and clay minerals were deposited contemporaneously at progressively greater distances from the intrusive contact (assemblage 1). At 4200 ?? 150 y BP, flank collapse and the formation of the volcano's crater, Kawah Galunggung, resulted in catastrophic decompression and boiling of the hydrothermal fluids. This event initiated development of the modern vapor-dominated regime. Chalcedony and then quartz were deposited as the early low salinity liquids boiled (assemblage 2). Both vapor- and liquid-rich fluid inclusions were trapped in the quartz crystals. Liquid-rich fluid inclusions from the southern part of the field record salinities ranging from 0 to 26 weight percent NaCl- CaCl2 equivalent and locally contain fluorite daughter crystals. We suggest, based on temperature-salinity relationships and evidence

  5. U of T to proceed with installation of $3.4-m Flu-Ace system

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1997-09-05

    The University of Toronto has awarded Thermal Energy a contract to install a $3.4-million Flu-Ace air pollution control and heat recovery system into its district heating plant. The new system will transform the heating plant into the most energy efficient and technologically advanced combined power plant and district heating plant of its size. The system is unique in that it combines heat recovery and air pollution control. It recovers up to 90 per cent of the heat normally lost in hot chimney flue gases. This reduces emissions of greenhouse gases, acid gases, nitrogen oxides, unburned hydrocarbons and particulates. The U of T project will be the thirteenth and the largest system built by Thermal Energy.

  6. Methane seepage along the Hikurangi Margin offshore New Zealand: 6 years of multidisciplinary studies

    Science.gov (United States)

    Greinert, J.; Bialas, J.; Klaucke, I.; Crutchley, G.; Dale, A.; Linke, P.; Sommer, S.; Bowden, D.; Rowden, A.; de Haas, H.; de Stigter, H.; Faure, K.

    2012-12-01

    Detailed studies in 2006, 2007 and 2011 along the east coast of New Zealand's North Island highlighted the close link of sub-bottom fluid pathways and seafloor expressions of methane seepage such as clam fields, carbonate build-ups, tubeworms, bacterial mats and methane release (Marine Geology 272). Prior to our studies, only accidental observations of hydroacoustic anomalies, recoveries of calyptogena shells and methane-derived carbonate chimneys indicated active seepage. Wide areas of the sub-seafloor show BSR structures, gas migration pathways, gas chimneys and blanking zones, which are closely linked to actual seep sites. Sidescan surveys showed four prominent seep areas at Omakere Ridge in 1120m water depth, three of them perfectly matching the shapes and locations of faults seen in high resolution 3D-seismic surveys. The fourth seep, Bear's Paw, on its western side represents an old seep which developed into a cold water coral habitat. At the actively seeping eastern part, gas hydrates could be retrieved and bubble release was observed hydroacoustically and confirmed by high dissolved methane values (380nM). No strong microbial oxidation effects could be found in δ13C values plotting along a mixing curve between pure seep (-70 ‰PDB) and atmospheric methane (-47 ‰PDB). Lander deployments show a tide-influenced gas discharge with sometimes eruptive bubble release with possible plume development transporting methane-charged water higher up into the water column. Rock Garden, with just above 600m water depth at its top outside the gas hydrate stability zone, hosts two main seep areas. ROV observations at Faure Site document eruptive releases of free gas from decimeter-wide craters at the seafloor. Flux estimates show peak releases of 420ml/min with bubbles up to 9mm in diameter. Concentrations of dissolved methane reach up to 3500nM close to the bottom, but higher concentrations are limited to below 400m of water depth; here, methane is transported towards

  7. Characterization of condensible and semivolatile organic materials from boise woodstove samples

    International Nuclear Information System (INIS)

    This paper presents the results from woodstove source and ambient sampling in Boise, ID. Data are presented for the total chromatographable organic, gravimetric, and gas chromatograph, mass spectrometric analyses of the volatile, semivolatile, and condensible organic fractions from XAD-2 and filter catches. The samples analyzed were obtained in the woodstove chimneys and in ambient locations representing the background, a residential area impacted by woodsmoke, and an urban area impacted by vehicular emissions. Included in the source emissions analysis are samples obtained in a laboratory setting as well as samples collected from houses in the field. Bioassay results on the laboratory samples are also presented. The Boise study was a multi-disciplinary, cross-EPA laboratory effort to apportion sources of mutagenicity in ambient emissions in a woodsmoke-impacted area

  8. Extrathyroidal Implantation of Thyroid Hyperplastic/neoplastic Cells after Endoscopic Thyroid Surgery

    Institute of Scientific and Technical Information of China (English)

    Cao Xi; Xie-qun Xu; Tao Hong; Bing-lu Li; Wei Liu

    2014-01-01

    Objective To report a case of the implantation of thyroid hyperplastic or neoplastic tissue after endoscopic thyroidectomy and discuss this complication in aspects of prevalence, pathogenesis, protection, and therapies. Methods A systematic search of literature from the PubMed database was conducted for identifying eligible studies on implantation of thyroid hyperplastic or neoplastic cells after endoscopic thyroid surgery. Results Overall, 5 reported cases on patients suffering from endoscopic thyroid surgery with implantation of thyroid hyperplastic or neoplastic cells were included in the systematic review. Conclusions Unskilled surgeons, rough intraoperative surgical treatment, scarification or rupture of tumor, contamination of instruments, chimney effect, aerosolization of tumor cells may be associated with the implantation after endoscopic thyroidectomy. To minimize the risk of such complication, we should be more meticulous and strict the endoscopic surgery indications.

  9. Body-Centered Orthorhombic C16 : A Novel Topological Node-Line Semimetal

    Science.gov (United States)

    Wang, Jian-Tao; Weng, Hongming; Nie, Simin; Fang, Zhong; Kawazoe, Yoshiyuki; Chen, Changfeng

    2016-05-01

    We identify by ab initio calculations a novel topological semimetal carbon phase in all-s p2 bonding networks with a 16-atom body-centered orthorhombic unit cell, termed bco-C16. Total-energy calculations show that bco-C16 is comparable to solid fcc-C60 in energetic stability, and phonon and molecular dynamics simulations confirm its dynamical stability. This all-s p2 carbon allotrope can be regarded as a three-dimensional modification of graphite, and its simulated x-ray diffraction (XRD) pattern matches well a previously unexplained diffraction peak in measured XRD spectra of detonation and chimney soot, indicating its presence in the specimen. Electronic band structure calculations reveal that bco-C16 is a topological node-line semimetal with a single nodal ring. These findings establish a novel carbon phase with intriguing structural and electronic properties of fundamental significance and practical interest.

  10. A study of the distribution of rare-metals in kuroko-type ore

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience]|[Geological Survey of Japan, Tsukuba, Ibaraki (Japan); Sie, S.H.; Suter, G.F. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

    1996-12-31

    We have performed PIXE analysis of kuroko-type ore from the JADE hydrothermal site of the Okinawa Trough, Japan using the proton microprobe (PIXEPROBE). We analysed five kinds of ores dredged from the sea floor: (I) barite ore with small sulfide dissemination; (2) sphalerite-pyrite chimney; (3) pyrite ore; (4) sulfide veinlets in strongly altered rock; and (5) pyrite megacrystals in strongly altered rock. The analyses revealed that the trace element distribution is regulated by the occurrence mode of the ore, and within each ore, by the crystal structure. The distribution suggests that the hydrothermal system for kuroko ore formation is quite heterogeneous and its chemistry is controlled by local factors such as difference in temperature, and that in-situ PIXE analyses are essential for effective beneficiation strategy for the rare-metals from kuroko-type ore. (authors). 10 refs., 1 tab.

  11. Benchmark of SIMULATE5 thermal hydraulics against the Frigg and NUPEC full bundle test experiments

    International Nuclear Information System (INIS)

    SIMULATE5 is Studsvik Scandpower's next generation nodal code. The core portion of the thermal hydraulic models of PWR and BWRs are treated as essentially identical, with each assembly having an active channel and a number of parallel water channels. In addition, the BWR assembly may be divided into four radial sub-assemblies. For natural circulation reactors, the BWR thermal hydraulic model is capable of modeling an entire vessel loop: core, chimney, upper plenum, standpipes, steam separators, downcomer, recirculation pumps, and lower plenum. This paper presents results of the validation of the BWR thermal hydraulic model against: (1) pressure drop data measured in the Frigg and NUPEC test facilities; (2) void fraction distribution measured in the Frigg and NUPEC loops; (3) quarter-assembly void fraction measured in the NUPEC experiments and (4) natural and forced circulation flow measurements in the Frigg loop. (author)

  12. An automated miniature robotic vehicle inspection system

    Science.gov (United States)

    Dobie, Gordon; Summan, Rahul; MacLeod, Charles; Pierce, Gareth; Galbraith, Walter

    2014-02-01

    A novel, autonomous reconfigurable robotic inspection system for quantitative NDE mapping is presented. The system consists of a fleet of wireless (802.11g) miniature robotic vehicles, each approximately 175 × 125 × 85 mm with magnetic wheels that enable them to inspect industrial structures such as storage tanks, chimneys and large diameter pipe work. The robots carry one of a number of payloads including a two channel MFL sensor, a 5 MHz dry coupled UT thickness wheel probe and a machine vision camera that images the surface. The system creates an NDE map of the structure overlaying results onto a 3D model in real time. The authors provide an overview of the robot design, data fusion algorithms (positioning and NDE) and visualization software.

  13. Heavy-Metal Aerosol Transport in a Lead-Bismuth-Cooled Fast Reactor with In-Vessel Direct-Contact Steam Generation

    International Nuclear Information System (INIS)

    The choice of lead or lead alloys (Pb-Bi) as the coolant of a fast reactor offers the potential for enhanced safety and reliability due to their benign physical and chemical characteristics. In an effort to assess this class of coolants in advanced nuclear systems of the next generation, an innovative fast reactor concept that eliminates the need for steam generators and main coolant pumps and thus offers capital and operating cost reduction was explored. The working steam is generated by direct-contact vaporization of water by liquid metal in the chimney above the core and is then sent directly to the turbine. The presence of a lighter fluid in the chimney substantially enhances the natural circulation of the Pb-Bi within the reactor pool. A key technical issue of this reactor concept is the consequences of Pb-Bi aerosol generation within the vessel, its transport within the power cycle components and impact on the design and operation of the turbine.Generation, transport, and deposition of Pb-Bi aerosols were modeled. It was found that the utilization of a suitable chevron steam separator design reduces the heavy-liquid metal transported to the steam lines by about three orders of magnitude. Nevertheless, the residual Pb-Bi (∼0.003 kg/s) is predicted to be sufficient to cause embrittlement of the turbine blades if conventional materials are used and the plant is to operate for 40 yr. Four solutions to this problem were assessed and found potentially viable from a technical standpoint: blade coating, employment of alternative materials, electrostatic precipitation, and oxidation of the Pb-Bi droplets

  14. Substrate pathways and mechanisms of inhibition in the sulfur oxygenase reductase of Acidianus ambivalens

    Directory of Open Access Journals (Sweden)

    Andreas eVeith

    2011-03-01

    Full Text Available Background: The sulfur oxygenase reductase (SOR is the initial enzyme of the sulfur oxidation pathway in the thermoacidophilic Archaeon Acidianus ambivalens. The SOR catalyzes an oxygen-dependent sulfur disproportionation to H2S, sulfite and thiosulfate. The spherical, hollow, cytoplasmic enzyme is composed of 24 identical subunits with an active site pocket each comprising a mononuclear non-heme iron site and a cysteine persulfide. Substrate access and product exit occur via apolar chimney-like protrusions at the four-fold symmetry axes, via narrow polar pores at the three-fold symmetry axes and via narrow apolar pores within in each subunit. In order to investigate the function of the pores we performed site-directed mutagenesis and inhibitor studies. Results: Truncation of the chimney-like protrusions resulted in an up to seven-fold increase in specific enzyme activity compared to the wild type. Replacement of the salt bridge-forming Arg99 residue by Ala at the three-fold symmetry axes doubled the activity and introduced a bias towards reduced reaction products. Replacement of Met296 and Met297, which form the active site pore, lowered the specific activities by 25-55 % with the exception of an M296V mutant. X-ray crystallography of SOR wild type crystals soaked with inhibitors showed that Hg2+ and iodoacetamide bind to cysteines within the active site, whereas Zn2+ binds to a histidine in a side channel of the enzyme. The Zn2+ inhibition was partially alleviated by mutation of the His residue. Conclusions: The expansion of the pores in the outer shell led to an increased enzyme activity while the integrity of the active site pore seems to be important. Hg2+ and iodoacetamide block cysteines in the active site pocket, while Zn2+ interferes over a distance, possibly by restriction of protein flexibility or substrate access or product exit.

  15. Mechanisms of suppressing cup-burner flame with water vapor

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The mechanisms of suppressing a laminar methane-air co-flow diffusion flame formed on a cup burner with water vapor have been studied experimentally and numerically. The methane burned in a steel cup surrounded by a glass chimney. A mist generator produced fine droplets delivered though the glass chimney with air. These droplets were heated into water vapor when they went though the diffuser. The extinguishing limit was obtained by gradually increasing the amount of water vapor to replace the air in the coflowing oxidizer stream. Results showed that the agent concentration required for extinguishment was constant over a wide range of the oxidizer velocity, i.e., a so-called "plateau region". The measured extinguishing mass fractions of the agents were: (16.7 ± 0.6)% for H2O, (15.9 ± 0.6)% for CO2, and (31.9 ± 0.6)% for N2. The computation used the Fire Dynamics Simulator (FDS) de- veloped by the NIST. The numerical simulations showed that the predicted water vapor extinguishing limits and the flickering frequency were in good agreements with the experimental observations and, more importantly, revealed that the sup- pression of cup-burner flames occurred via a partial extinction mechanism (in which the flame base drifts downstream and then blows off) rather than the global extinction mechanism of typical counter-flow diffusion flames. And the flame-base oscillation just before the blow-off was the key step for the non-premixed flame extinction in the cup burner.

  16. Mechanisms of suppressing cup-burner flame with water vapor

    Institute of Scientific and Technical Information of China (English)

    CONG BeiHua; LIAO GuangXuan

    2008-01-01

    The mechanisms of suppressing a laminar methane-air co-flow diffusion flame formed on a cup burner with water vapor have been studied experimentally and numerically. The methane burned in a steel cup surrounded by a glass chimney. A mist generator produced fine droplets delivered though the glass chimney with air. These droplets were heated into water vapor when they went though the diffuser. The extinguishing limit was obtained by gradually increasing the amount of water vapor to replace the air in the coflowing oxidizer stream. Results showed that the agent concentration required for extinguishment was constant over a wide range of the oxidizer velocity, i.e., a so-called "plateau region". The measured extinguishing mass fractions of the agents were: (16.7±0.6)% for H2O, (15.9±0.6)% for CO2, and (31.9±0.6)% for N2. The computation used the Fire Dynamics Simulator (FDS) de-veloped by the NIST. The numerical simulations showed that the predicted water vapor extinguishing limits and the flickering frequency were in good agreements with the experimental observations and, more importantly, revealed that the sup-pression of cup-burner flames occurred via a partial extinction mechanism (in which the flame base drifts downstream and then blows off) rather than the global extinction mechanism of typical counter-flow diffusion flames. And the flame-base oscillation just before the blow-off was the key step for the non-premixed flame extinction in the cup burner.

  17. Low temperature geomicrobiology follows host rock composition along a geochemical gradient in Lau Basin

    Directory of Open Access Journals (Sweden)

    Jason B Sylvan

    2013-03-01

    Full Text Available The East Lau Spreading Center (ELSC and Valu Fa Ridge (VFR comprise a ridge segment in the southwest Pacific Ocean where rapid transitions in the underlying mantle chemistry manifest themselves as gradients in seafloor rock geochemistry. We studied the geology and microbial diversity of three silicate rock samples and three inactive sulfide chimney samples collected, from north to south, at the vent fields Kilo Moana, ABE, Tui Malila and Mariner. This is the first study of microbial populations on basaltic andesite, which was sampled at Mariner vent field. Silicate rock geochemistry exhibits clear latitudinal trends that are mirrored by changes in bacterial community composition. α-proteobacteria, ε-proteobacteria and Bacteroidetes are most common on a silicate collected from Kilo Moana and their proportions decrease linearly on silicates collected further south. Conversely, a silicate from Mariner vent field hosts high proportions of a unique lineage of Chloroflexi unrelated (<90% sequence similarity to previously recovered environmental clones or isolates, which decrease at ABE and are absent at Kilo Moana. The exteriors of inactive sulfide structures are dominated by lineages of sulfur oxidizing α-proteobacteria, γ-proteobacteria and ε-proteobacteria while the interior of one chimney is dominated by putative sulfur-reducing δ-proteobacteria. A comparison of bacterial communities on inactive sulfides from this and previous studies reveals the presence of a clade of uncultured Bacteroidetes exclusive to sulfidic environments, and a high degree of heterogeneity in bacterial community composition from one sulfide structure to another. In light of the heterogeneous nature of bacterial communities observed here and in previous studies of both active and inactive hydrothermal sulfide structures, the presence of numerous niches may be detected on these structures in the future by finer scale sampling and analysis.

  18. Topographic features of gas hydrate mounds of shallow gas hydrate areas in Joetsu Basin , eastern margin of Japan Sea

    Science.gov (United States)

    Hiromatsu, M.; Machiyama, H.; Matsumoto, R.

    2010-12-01

    Mega pockmarks and mounds, both of which are 300m to 500m in diamater and 30m to 40 m deep or high, characterize the Umitaka Spur and Joetsu Knoll of the Joetsu Basin. A number of pockmarks and mounds develop in NNE to SSW direction parallel to the general trend of mobile belt along the eastern margin of Japan Sea, suggesting that the topography has been strongly controlled by regional tectonics. Seismic profiles have revealed well-developed chaotic to transparent zones (gas chimneys) in the area of pockmarks and mounds, from which a number of active methane plumes stand up to 700m above sea floor. Ultra-high resolution bathymetric data and reflection images were acquired by Multi Beam Echo Sounder (MBES) and Side Scan Sonar (SSS) of the AUV "URASHIMA” during the YK10-08 cruise of R/V Yokosuka (JAMSTEC), July 2010. Based on mosaic images of MBES and SSS, we could identify several types of the hydrate mounds over gas chimney zones. Some are represented as a smooth and low bulge without strong reflections of background level, but the others show rough and uneven topography, featured by a few meter scale depressions, crevasses and minor ridges with strong reflector images, indicating the development of hard ground. Such strong reflectors are due to carbonate crusts and concretions and gas hydrate exposures as observed by ROV . Micro-topographic features are likely to represent a growth stage of hydrate mounds, and perhaps the accumulation of shallow gas hydrates. MBES and SSS onboard AUV are powerful tools to identify gas hydrate accumulation and evolution of shallow gas hydrate system.

  19. Sri Lanka Pilot Study to Examine Respiratory Health Effects and Personal PM2.5 Exposures from Cooking Indoors

    Directory of Open Access Journals (Sweden)

    Michael J. Phillips

    2016-08-01

    Full Text Available A pilot study of indoor air pollution produced by biomass cookstoves was conducted in 53 homes in Sri Lanka to assess respiratory conditions associated with stove type (“Anagi” or “Traditional”, kitchen characteristics (e.g., presence of a chimney in the home, indoor cooking area, and concentrations of personal and indoor particulate matter less than 2.5 micrometers in diameter (PM2.5. Each primary cook reported respiratory conditions for herself (cough, phlegm, wheeze, or asthma and for children (wheeze or asthma living in her household. For cooks, the presence of at least one respiratory condition was significantly associated with 48-h log-transformed mean personal PM2.5 concentration (PR = 1.35; p < 0.001. The prevalence ratio (PR was significantly elevated for cooks with one or more respiratory conditions if they cooked without a chimney (PR = 1.51, p = 0.025 and non-significantly elevated if they cooked in a separate but poorly ventilated building (PR = 1.51, p = 0.093. The PRs were significantly elevated for children with wheeze or asthma if a traditional stove was used (PR = 2.08, p = 0.014 or if the cooking area was not partitioned from the rest of the home (PR = 2.46, p = 0.012. For the 13 children for whom the cooking area was not partitioned from the rest of the home, having a respiratory condition was significantly associated with log-transformed indoor PM2.5 concentration (PR = 1.51; p = 0.014.

  20. Seismic evidence of methane cycling between deep and shallow fluid flow systems along the Hikurangi margin, New Zealand

    Science.gov (United States)

    Plaza-Faverola, A.; Pecher, I.; Klaeschen, D.; Henrys, S.

    2012-04-01

    Determining the source of the main natural gas, methane, forming gas hydrates, i.e. whether it is microbial or thermogenic, remains one of the main challenges in gas hydrate research. Geochemical data suggest that most of the methane that seep out from the seafloor above gas hydrate zones is microbial. However, significant volumes of free gas trapped beneath the base of the gas hydrate stability zone and the presence of faults and gas chimneys that link deep sited thermogenic gas reservoirs with the hydrate zones are evidence of fluid exchange between deep and shallow systems. We have reprocessed 10 and 12 km long surface streamer multi-channel seismic data from the Opouawe Bank and Porangahau Ridge regions along the Hikurangi Margin in order to obtain realistic geometries of fluid escape features associated with the subduction interface. Pre-stack depth migrated images of the subsurface show thrust faults linking the subduction interface with the gas hydrate zone. Anticlinal features with deeply rooted gas chimneys at their flanks and polygonal faults above the subduction interface are also evidence of fluid expulsion from the subdcuted sediments towards the gas hydrate zone. Further, anomalous low velocity zones in P-wave velocity macro models indicate preferred locations for fluid accumulations in sediments between the gas hydrate zone and the subduction interface. In order to explain the dominant microbial signature of methane sampled at the surface in spite of evident migration of fluids from well beneath the microbial zone, we present a model where microbial methane has been expelled from buried sediments together with thermogenic methane at different periods of overpressure related to the subduction system. We expect signatures for thermogenic methane to be found deeper than maximum depths of conventional coring (i.e. > 30 mbsf) in the sedimentary column. Our results complement an ongoing multidisciplinary investigation of gas hydrate systems along Hikurangi

  1. ASSESSMENT OF HYDROCARBON SEEPAGE DETECTION METHODS ON THE FORT PECK RESERVATION, NORTHEAST MONTANA

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence M. Monson

    2003-06-30

    Surface exploration techniques have been employed in separate study areas on the Fort Peck Reservation in northeastern Montana. Anomalies associated with hydrocarbon seepage are documented in all three areas and a variety of surface exploration techniques can be compared. In a small area with established production, Head Gas and Thermal Desorption methods best match production; other methods also map depletion. In a moderate-size area that has prospects defined by 3D seismic data, Head Gas along with Microbial, Iodine, and Eh soil anomalies are all associated with the best hydrocarbon prospect. In a large area that contains many curvilinear patterns observed on Landsat images, that could represent micro-seepage chimneys, results are inconclusive. Reconnaissance mapping using Magnetic Susceptibility has identified a potential prospect; subsequent Soil Gas and Head Gas surveys suggest hydrocarbon potential. In the final year of this project the principle contractor, the Fort Peck Tribes, completed a second survey in the Wicape 3D Seismic Prospect Area (also known as Area 6 in Phase I of the project) and sampled several Landsat image features contained in the Smoke Creek Aeromag Anomaly Area (also known as Area 1 in Phase II of the project). Methods determined to be most useful in Phases I and II, were employed in this final Phase III of the study. The Southwest Wicape seismic anomaly was only partially confirmed. The abundant curvilinears proposed to be possible hydrocarbon micro-seepage chimneys in the Smoke Creek Area were not conclusively verified as such. Insufficient sampling of background data precludes affirmative identification of these mostly topographic Landsat features as gas induced soil and vegetation anomalies. However relatively higher light gas concentrations were found associated with some of the curvilinears. Based on the findings of this work the Assiniboine & Sioux Tribes of the Fort Peck Reservation intend to utilize surface hydrocarbon

  2. Solar dryer with thermal storage and biomass-backup heater

    Energy Technology Data Exchange (ETDEWEB)

    Madhlopa, A. [Department of Physics and Biochemical Sciences, Malawi Polytechnic, P/Bag 303, Blantyre 3 (Malawi); Ngwalo, G. [Department of Mechanical Engineering, Malawi Polytechnic, P/Bag 303, Blantyre 3 (Malawi)

    2007-04-15

    An indirect type natural convection solar dryer with integrated collector-storage solar and biomass-backup heaters has been designed, constructed and evaluated. The major components of the dryer are biomass burner (with a rectangular duct and flue gas chimney), collector-storage thermal mass and drying chamber (with a conventional solar chimney). The thermal mass was placed in the top part of the biomass burner enclosure. The dryer was fabricated using simple materials, tools and skills, and it was tested in three modes of operation (solar, biomass and solar-biomass) by drying twelve batches of fresh pineapple (Ananas comosus), with each batch weighing about 20 kg. Meteorological conditions were monitored during the dehydration process. Moisture and vitamin C contents were determined in both fresh and dried samples. Results show that the thermal mass was capable of storing part of the absorbed solar energy and heat from the burner. It was possible to dry a batch of pineapples using solar energy only on clear days. Drying proceeded successfully even under unfavorable weather conditions in the solar-biomass mode of operation. In this operational mode, the dryer reduced the moisture content of pineapple slices from about 669 to 11% (db) and yielded a nutritious dried product. The average values of the final-day moisture-pickup efficiency were 15%, 11% and 13% in the solar, biomass and solar-biomass modes of operation respectively. It appears that the solar dryer is suitable for preservation of pineapples and other fresh foods. Further improvements to the system design are suggested. (author)

  3. A two-dimensional model of the passive coastal margin deep sedimentary carbon and methane cycles

    Directory of Open Access Journals (Sweden)

    D. E. Archer

    2012-03-01

    Full Text Available We present a new geologic-time and basin-spatial scale model of the continental margin methane cycle. The model, SpongeBOB, is used to simulate evolution of the carbon cycle in a passive sedimentary continental margin in response to changing oceanographic and geologic forcing over a time scale of 140 million years. The model is somewhat less sensitive to temperature than our previous results with a one-dimensional model, but is more sensitive to reasonable changes in POC than it is to reasonable changes in temperature. This behavior could lead to higher inventories of hydrate during hothouse climate conditions, rather than lower as generally assumed, due to the enrichment of the sediments in organic carbon. The hydrate inventory in the model is extremely sensitive to the ability of methane bubbles to rise within the sediment column, and how far gas-phase methane can get through the sediment column before it redissolves when it reaches undersaturated conditions. Hydrate formation is also sensitive to deep respiration of migrating petroleum in the model. The geochemistry of the sediment column is altered by the addition of vertical high-permeability chimneys intended to mimic the effects of heterogeneity in the real sediment column due to faults and chimneys, and produces results consistent with measured pore-water tracers SO42− and 129I. Pore water DIC concentrations are consistent with chemical weathering at depth within the sediment column. The carbon isotopic composition of the DIC is consistent with a methane production efficiency from POC of 50%, which is somewhat lower than redox balance with the H/C of organic matter in the model. Other phenomena which we simulated had only small impact on the hydrate inventory, including thermogenic methane, dissolved organic carbon, and sediment transport characteristics.

  4. The metatranscriptome of a deep-sea hydrothermal plume is dominated by water column methanotrophs and lithotrophs.

    Science.gov (United States)

    Lesniewski, Ryan A; Jain, Sunit; Anantharaman, Karthik; Schloss, Patrick D; Dick, Gregory J

    2012-12-01

    Microorganisms mediate geochemical processes in deep-sea hydrothermal vent plumes, which are a conduit for transfer of elements and energy from the subsurface to the oceans. Despite this important microbial influence on marine geochemistry, the ecology and activity of microbial communities in hydrothermal plumes is largely unexplored. Here, we use a coordinated metagenomic and metatranscriptomic approach to compare microbial communities in Guaymas Basin hydrothermal plumes to background waters above the plume and in the adjacent Carmen Basin. Despite marked increases in plume total RNA concentrations (3-4 times) and microbially mediated manganese oxidation rates (15-125 times), plume and background metatranscriptomes were dominated by the same groups of methanotrophs and chemolithoautotrophs. Abundant community members of Guaymas Basin seafloor environments (hydrothermal sediments and chimneys) were not prevalent in the plume metatranscriptome. De novo metagenomic assembly was used to reconstruct genomes of abundant populations, including Marine Group I archaea, Methylococcaceae, SAR324 Deltaproteobacteria and SUP05 Gammaproteobacteria. Mapping transcripts to these genomes revealed abundant expression of genes involved in the chemolithotrophic oxidation of ammonia (amo), methane (pmo) and sulfur (sox). Whereas amo and pmo gene transcripts were abundant in both plume and background, transcripts of sox genes for sulfur oxidation from SUP05 groups displayed a 10-20-fold increase in plumes. We conclude that the biogeochemistry of Guaymas Basin hydrothermal plumes is mediated by microorganisms that are derived from seawater rather than from seafloor hydrothermal environments such as chimneys or sediments, and that hydrothermal inputs serve as important electron donors for primary production in the deep Gulf of California.

  5. Sri Lanka Pilot Study to Examine Respiratory Health Effects and Personal PM2.5 Exposures from Cooking Indoors.

    Science.gov (United States)

    Phillips, Michael J; Smith, Emily A; Mosquin, Paul L; Chartier, Ryan; Nandasena, Sumal; Bronstein, Katherine; Elledge, Myles F; Thornburg, Vanessa; Thornburg, Jonathan; Brown, Linda M

    2016-01-01

    A pilot study of indoor air pollution produced by biomass cookstoves was conducted in 53 homes in Sri Lanka to assess respiratory conditions associated with stove type ("Anagi" or "Traditional"), kitchen characteristics (e.g., presence of a chimney in the home, indoor cooking area), and concentrations of personal and indoor particulate matter less than 2.5 micrometers in diameter (PM2.5). Each primary cook reported respiratory conditions for herself (cough, phlegm, wheeze, or asthma) and for children (wheeze or asthma) living in her household. For cooks, the presence of at least one respiratory condition was significantly associated with 48-h log-transformed mean personal PM2.5 concentration (PR = 1.35; p < 0.001). The prevalence ratio (PR) was significantly elevated for cooks with one or more respiratory conditions if they cooked without a chimney (PR = 1.51, p = 0.025) and non-significantly elevated if they cooked in a separate but poorly ventilated building (PR = 1.51, p = 0.093). The PRs were significantly elevated for children with wheeze or asthma if a traditional stove was used (PR = 2.08, p = 0.014) or if the cooking area was not partitioned from the rest of the home (PR = 2.46, p = 0.012). For the 13 children for whom the cooking area was not partitioned from the rest of the home, having a respiratory condition was significantly associated with log-transformed indoor PM2.5 concentration (PR = 1.51; p = 0.014). PMID:27527203

  6. How to transform an asphalt concrete pavement into a solar turbine

    International Nuclear Information System (INIS)

    Highlights: • We create a system for harvesting energy from asphalt concrete. • We create an artificial porosity in the asphalt concrete. • We connect a chimney to this porosity. • Differences in temperature produce an air flow. • This air flow serves also for cooling down the pavement. - Abstract: Asphalt concrete can absorb a considerable amount of the incident solar radiation. For this reason asphalt roads could be used as solar collectors. There have been different attempts to achieve this goal. All of them have been done by integrating pipes conducting liquid, through the structure of the asphalt concrete. The problem of this system is that all pipes need to be interconnected: if one is broken, the liquid will come out and damage the asphalt concrete. To overcome these limitations, in this article, an alternative concept is proposed:parallel air conduits, where air can circulate will be integrated in the pavement structure. The idea is to connect these artificial pore volumes in the pavement to an updraft or to a downdraft chimney. Differences of temperature between the pavement and the environment can be used to create an air flow, which would allow wind turbines to produce an amount of energy and that would cool the pavement down in summer or even warm it up in winter. To demonstrate that this is possible, an asphalt concrete prototype has been created and basics calculations on the parameters affecting the system have been done. It has been found that different temperatures, volumes of air inside the asphalt and the difference of temperature between the asphalt concrete and the environment are critical to maximize the air flow through the pavement. Moreover, it has been found that this system can be also used to reduce the heat island effect

  7. Optimization of Q-factor of AFM cantilevers using genetic algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Cruz, Angel, E-mail: elapc27@gmail.com [Faculty of Engineering, Universidad Autonoma de Queretaro, Queretaro (Mexico); Dominguez-Gonzalez, Aurelio [Faculty of Engineering, Universidad Autonoma de Queretaro, Queretaro (Mexico); Stiharu, Ion [Department of Mechanical and Industrial Engineering, Concordia University, Montreal (Canada); Osornio-Rios, Roque A. [Faculty of Engineering, Universidad Autonoma de Queretaro, Queretaro (Mexico)

    2012-04-15

    Micro cantilever beams have been intensively used in sensing applications including to scanning profiles and surfaces where there resolution and imaging speed are critical. Force resolution is related to the Q-factor. When the micro-cantilever operates in air with small separation gaps, the Q-factor is even more reduced due to the squeeze-film damping effect. Thus, the optimization of the configuration of an AFM micro-cantilever is presented in this work with the objective of improving its Q-factor. To accomplish this task, we propose the inclusion of holes as breathing chimneys in the initial design to reduce the squeeze-film damping effect. The evaluation of the Q-factor was carried out using finite element model, which is implemented to work together with the squeeze-film damping model. The methodology applied in the optimization process was genetic algorithms, which considers as constraints the maximum allowable stress, fundamental frequency and spring constant with respect to the initial design. The results show that the optimum design, which includes holes with an optimal location, increases the Q-factor almost five times compared to the initial design. -- Highlights: Black-Right-Pointing-Pointer It was optimized the Q-factor of a cantilever, which operates near to the surface in air. Black-Right-Pointing-Pointer It was proposed the inclusion of holes as breathing chimneys in the cantilever's surface. Black-Right-Pointing-Pointer Genetic algorithms and finite element analysis were applied to find the optimum configuration for the Q-factor. Black-Right-Pointing-Pointer Optimum design keeps first frequency and the spring constant very close to the original and has a better force resolution. Black-Right-Pointing-Pointer Final design can be easily manufactured through a mask.

  8. Hypnotic effect of the essential oil from the leaves of Myrtus communis on mice

    Directory of Open Access Journals (Sweden)

    Birhanie MW

    2016-08-01

    Full Text Available Muluken Walle Birhanie,1 Bizuayehu Walle,1 Kidist Rebba2 1Department of Physiology, 2Department of Nursing, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia Background: Myrtus communis has been suggested as a sleep aid in unconventional medicine. Moreover, previous studies have also indicated its sedative- and hypnotic-like activity. In this study, the hypnotic effect of M. communis was investigated.Methods: Essential oil (EO of M. communis (600, 800, and 1,000 mg/kg was given orally to Swiss albino mice of both sex, and the hypnotic effect was evaluated. In addition, the EO of M. communis (500, 600, 800, and 1,000 mg/kg was administered orally to Swiss albino mice of both sex 60 minutes prior to pentobarbital injection (50 mg/kg. Latency to sleep and sleep duration were recorded. The effect of the EO on motor coordination and muscle relaxation was evaluated using chimney and traction tests, 60 and 90 minutes after administration of the respective doses of the EO, respectively.Results: There was no induction of hypnosis as the presence of the righting reflex was intact. However the EO prolonged pentobarbital-induced sleeping time and there was also 50% negative response on the chimney and traction test in a dose dependent manner.Conclusion: The EO of M. communis did not produce a hypnotic effect, but it potentiated a hypnotic effect with significant central nervous system depressant activity. Keywords: Myrtus communis, hypnotic, motor coordination, muscle relaxation, essential oil

  9. Reducing Scattered Light in CCD Images at the CTIO 0.9m Telescope

    Science.gov (United States)

    Barnaby, D.; Rauscher, B. J.

    1998-12-01

    We have been studying luminous halos around spiral galaxies in very deep near-infrared K-band images (limiting surface brightness =24 mag arcsec(-2) ; lambda_ {c} = 2.35 mu m). Following our successful detection of a halo around the southern spiral galaxy ESO 240-G11 (Rauscher et al. 1998), we collected optical CCD images of candidate galaxies at the Cerro Tololo Interamerican Observatory (CTIO) 0.9 m telescope from 17-21 Sept 1998. Because light scattered by the telescope can mask or mimic faint, extended emission, we took precautions to minimize stray and scattered light. To assess the amount of scattered light, we collected images of the telescope pupil using a pinhole camera, which we constructed by laying a sheet of aluminum foil, perforated with a submillimeter hole, 19 mm in front of the CCD. These images showed that the telescope did scatter light on the order of a few percent over a radius of about 2 arcminutes. Supressing this extraneous light was highly desirable, since halo surface brightness can be baffles. One baffle consisted of a 0.95 m diameter tube added as an extension to the telescope, which has a closed-tube design. The other 2 baffles were diaphragms mounted between the primary baffle (the ``chimney'') and the shutter. These baffles effectively eliminated the largest sources of scattered light, which appear to be the edge of the secondary baffle and the inner surface of the chimney (Figure 1, http:// astro.uchicago.edu/home/web/barnaby/sctrdlite98.html). In this paper, we quantify the reduction in scattered light and examine the most useful location to add baffles to this telescope. Acknowledgements. We thank the CTIO Telescope Operations staff for their help in constructing and installing the baffles. We also thank support astronomer Nick Suntzeff for suggesting the pinhole tests. Rauscher, B. J. et al. 1998, ApJ, 506, 116

  10. Clavulanic acid does not affect convulsions in acute seizure tests in mice.

    Science.gov (United States)

    Gasior, Maciej; Socała, Katarzyna; Nieoczym, Dorota; Wlaź, Piotr

    2012-01-01

    Clavulanic acid (CLAV) inhibits bacterial β-lactamases and is commonly used to aid antibiotic therapy. Prompted by the initial evidence suggestive of the potential anticonvulsant and neuroprotective properties of CLAV, the present study was undertaken to systematically evaluate its acute effects on seizure thresholds in seizure tests typically used in primary screening of potential antiepileptic drugs (AEDs). In the present study, 6-Hz seizure threshold, maximal electroshock seizure threshold (MEST) test, and intravenous pentylenetetrazole (i.v. PTZ) seizure tests were used to determine anticonvulsant effects of intraperitoneally (i.p.) administered CLAV in mice. Acute effects on motor coordination and muscle strength were assessed in the chimney and grip-strength tests, respectively. Doses of CLAV studied in the present study were either comparable or extended the doses reported in the literature to be effective against kainic acid-induced convulsions in mice or behaviorally active in rodents and monkeys. CLAV had no effect on seizure thresholds in the 6-Hz (64 ng/kg to 1 mg/kg) and MEST (64 ng/kg to 5 mg/kg) seizure tests. Similarly, CLAV had no effect on seizure thresholds for i.v. PTZ-induced myoclonic twitch, clonic convulsions, and tonic convulsions (64 ng/kg to 5 mg/kg). Finally, CLAV (64 ng/kg to 5 mg/kg) had no effect on the motor performance and muscle strength in the chimney and grip-strength tests, respectively. In summary, CLAV failed to affect seizure thresholds in three seizure tests in mice. Although the results of the present study do not support further development of CLAV as an AED, its beneficial effects in chronic epilepsy models warrant further evaluation owing to its, for example, potential neuroprotective properties.

  11. Exhalative Lead-Zinc Deposits in Shallow Sea, Southern Xicheng Belt, Gansu Province

    Institute of Scientific and Technical Information of China (English)

    ZHU Xinyou; WANG Dongbo; WEI Zhiguo; QIU Xiaoping; WANG Ruiting

    2008-01-01

    SEDEX-type lead-zinc deposits in the southern belt of the Xicheng Devonian basin, GansuProvince has been already identified. However, the sedimentary environment of the limestone andphilite of the Xihanshui Group within which the lead-zinc deposits occur is littoral and shallow sea.This is different from those in the northern belt such as the Changba-Lijiagou lead-zinc deposits, whichwere formed in deep sea. The reef and bioclastic limestone are widespread in the southern belt.Particularly they are associated with lead-zinc ores and there are no striae and banding but massive ordisseminated structures. It is discovered that the black chimney consists of sphalerite, ankerite, pyriteand galena, in which black, coarse and radial sphalerite occurs as irregularly veins or cylindricafitywith a width of 10-40 cm in the center, and it is surround by fine ankerite and minor celestite withribbon structure. The immediate wall rock of the chimney, reef limestone, was unaltered and theoutside reef and bioclastic limestone were intensively silicified. Those silicified reef and bioclasticlimestone host disseminated lead-zinc ores of the Lnoba and Bijiashan type. It is concluded that theexhalative system occurred in a shallow sea in the Givetian of the middle Devonian. Brine is boiled dueto low pressure, and a great deal of lead and zinc was dispersed in the interface between the limestoneand phyllite and formed a source bed. In the Triassic period, meta-hydrothermai fluids leached andextracted metals from the source bed, and then moved and mineralized in open space such as archesand inverse limbs of anticlines, and formed massive and vein ores such as the Jianyagou andDengjiashan type deposits.

  12. Radon as geological tracer

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, T.; Anjos, R.M. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Fisica; Valladares, D.L.; Rizzotto, M.; Velasco, H.; Ayub, J. Juri [Universidad Nacional de San Luis (Argentina). Inst. de Matematica Aplicada San Luis (IMASL); Silva, A.A.R. da; Yoshimura, E.M. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

    2012-07-01

    Full text: This work presents measurements of {sup 222}Rn levels performed in La Carolina gold mine and Los Condores tungsten mine at the province of San Luis, Argentina, today used for tourist visitation, and can evaluate the potential use of such radioactive noble gas as tracer or marker for geological processes in underground environments. By concentrations of {sup 40}K, {sup 232}Th and {sup 23}'8U were also measured in the walls of tunnels were determined the rocks mineral composition, what indicated that the mines have the same composition. In this sense, we used nuclear trace plastic detectors CR-39, gamma spectrometry of rock samples and Geiger-Muller (GM) monitors The patterns of radon gas transportation processes revealed that La Carolina could be interpreted through a model based on a radioactive gas confined into a single entrance tube, with constant cross section and air velocity. Los Condores, which has a second main entrance, could be interpreted through a model based on a radioactive gas confined into a two entrance tube, allowing a chimney effect for air circulation. The results showed the high potential of using {sup 222}Rn as a geological tracer. In what concerns the occupational hazard, in summer (time of more intense tourist activity in the mine) La Carolina presented a mean concentration of the radioactive noble gas that exceeds in four times the action level of 1,5 kBq m{sup -3} recommended by the International Commission of Radiological Protection (ICRP). The chimney effect shows the low mean concentration of radon in Los Condores. (author)

  13. Submarine Hydrothermal Systems - No Two Fields Are Alike

    Science.gov (United States)

    Kelley, D. S.

    2014-12-01

    Over 300 hydrothermal systems have been discovered since the first finding of Galapagos vents over three decades ago. The size, morphology, chemistry and associated biology show a rich diversity that is in part governed by their host rocks and tectonic setting. Each vent system is unique in terms of the morphology of black smoker edifices and associated diffuse flow, which suggests that local processes and feedback loops govern the nature and evolution of these dynamic systems. In fast-spreading environments (e.g. EPR), vent fields are spaced far apart and individual structures are small in number and size. In contrast, to date, the highest concentrations of fields per kilometer of ridge segment, and the largest individual black smokers occur in intermediate-spreading systems (e.g. Endeavour hosting 45 m-tall chimneys). The largest complexes occur in intermediate and slow-spreading environments (e.g. TAG at 200 m across). The highest temperature vents are transient, with temperature excursions at or above the critical point of seawater. Extremely high temperatures are associated with diking and eruptive events that likely vaporize subsurface fluids, forcing them across the two-phase boundary briefly. Along slow- and ultraslow-spreading ridges, the character of vents is strongly controlled by faulting, in particular, long-lived detachment faults that expose variably deformed and altered ultramafic rocks. Here, vent systems evolve from high-temperature black smokers within the axial valley with fluids rich in CO2, to black smokers with mantle and basaltic signatures along the axial valley walls, to end member systems such as the Lost City Field with chimneys and fluid chemistries never before seen: 60 m tall limestone towers that vent 90°C, metal-poor, pH 9-11 fluids devoid of CO2, yet rich in H2, CH4 and other low molecular weight hydrocarbons formed abiotically. This relatively stable environment, free from volcanic events, promotes venting for >150,000 years.

  14. Radionuclide concentration from peat burning after the Chernobyl accident

    International Nuclear Information System (INIS)

    We have studied the radionuclide concentrations in byproducts and releases from a 30 MW peat-burning power plant in central Sweden. The plant is located in an area that received high levels of radioactive fall-out from the Chernobyl accident. After the accident at Chernobyl, the plant carried out a test run before the beginning of the normal running season. Samples of peat and ash were collected during a 2 month period and were studied in order to ascertain whether radiation protection was necessary for workers handling the peat and byproducts. In spite of the high ground contamination of radionuclides (20-80 kBq/M2) of the peat, the radionuclide concentration in the peat was only about 1 kBq/kg (and half of this one year later). This is due to the process in which the top 50 cm layer of peat is continously mixed and turned over. Samples of fly ash from different parts of the plant, analysed using gamma-ray spectroscopy, were found to have activity concentrations of 10-50 kBq/kg Cs-137, while the activity concentrations of bottom ash was 4-10 kBq/kg. During the winter of 1984-85 the average level of Cs-137 in the flyash was 340 Bq/kg. Condensed water from the chimney did not contain any measurable amounts of Cs-137. Emission measurements of the gases in the chimney gave rather high activity concentrations of Cs-137. The maximum value of 70 kBq/kg was probably due to the ease with which caesium escapes during heating. No special radiation steps were found to be necessary

  15. Experimental Evaluation of Installed Cooking Exhaust Fan Performance

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Brett C.; Delp, William W.; Apte, Michael G.

    2010-11-01

    The installed performance of cooking exhaust fans was evaluated through residential field experiments conducted on a sample of 15 devices varying in design and other characteristics. The sample included two rear downdraft systems, two under-cabinet microwave over range (MOR) units, three different installations of an under-cabinet model with grease screens across the bottom and no capture hood, two devices with grease screens covering the bottom of a large capture hood (one under-cabinet, one wall-mount chimney), four under-cabinet open hoods, and two open hoods with chimney mounts over islands. Performance assessment included measurement of airflow and sound levels across fan settings and experiments to quantify the contemporaneous capture efficiency for the exhaust generated by natural gas cooking burners.Capture efficiency is defined as the fraction of generated pollutants that are removed through the exhaust and thus not available for inhalation of household occupants. Capture efficiency (CE) was assessed for various configurations of burner use (e.g., single front, single back, combination of one front and one back, oven) and fan speed setting. Measured airflow rates were substantially lower than the levels noted in product literature for many of the units. This shortfall was observed for several units costing in excess of $1000. Capture efficiency varied widely (from<5percent to roughly 100percent) across devices and across conditions for some devices. As expected, higher capture efficiencies were achieved with higher fan settings and the associated higher air flow rates. In most cases, capture efficiencies were substantially higher for rear burners than for front burners. The best and most consistent performance was observed for open hoods that covered all cooktop burners and operated at higher airflow rates. The lowest capture efficiencies were measured when a front burner was used with a rear backdraft system or with lowest fan setting for above the range

  16. THE DIVERSITY AND DISTRIBUTION OF ARCHAEA IN GUAYMAS DEEP-SEA HYDROTHERMAL VENT%瓜伊马斯深海热液口古菌分布及多样性研究

    Institute of Scientific and Technical Information of China (English)

    鲁书林; 何莹; 王风平

    2013-01-01

    Due to the dramatic gradients of temperature (up to above 400℃ ) ,pH and chemicals, deep-sea hydrothermal vents have been the focus for studies of the origin and evolution of life on earth and the subseafloor hydrothermal living system is ideal for exploring the origin and evolution of deep-sea life. In this study, the diversity of archaea was investigated at high temperature sediments and chimney from Guaymas hydrothermal vent using cultured-independent technique. Environmental total DNA were directly extracted and used for the quantification and construction of archaea 16S rRNA gene libraries. A total of 79 and 80 clean sequences were obtained from the sediment and chimney samples. Quantitative PCR analysis revealed that the amounts of archaea present in the sediment and chimney were about 1.47×109 copies/g ( wet weight) and 5. 29 × 108 copies/g ( wet weight), respectively. All the clone libraries had the coverage C value more than 80%, the archaea diversity of sediment sample was higher than the chimney. The compositions of archaea community were different between two samples, yet most of archaea belonged to the thermophilic/hyperthermophilic microorganism because of the high temperature environment. In the sediments, most of archaea came from Crenarchaeota domain and the two most dominant groups were the Miscellaneous Crenarchaeota Group ( MCG,43. 04% )and Hot Water Crenarchaeota Group Ⅰ ( HWCG Ⅰ , 20. 25% ) confirmed by archaeal 16S rRNA gene components. The remaining sequences from the sediment sample were related to members of Thermoprotei ( 7. 59%) , Korarchaeota ( 1. 26%) , Methanosarcinales (1. 26%) , Marine Benthic Group D/Deep Hydrothermal Vent Euryarchaeota ( MBGD/DHVE 1, 8. 86%) , DHVE 9 ( 5. 06%) , Miscellaneous Euryarchaeota Group ( MEG, 2. 53%). While the Euryarchaeota domain dominated the chimney sample, in which Thermococcales (47.5%), Marine Benthic Group D ( MBGD )/Deep Hydrothermal Vent Euryarchaeota 1 ( DHVE 1) ( MBGD/DHVE 1

  17. Brine Migration from a Flooded Salt Mine in the Genesee Valley, Livingston County, New York: Geochemical Modeling and Simulation of Variable-Density Flow

    Science.gov (United States)

    Yager, Richard M.; Misut, Paul E.; Langevin, Christian D.; Parkhurst, David L.

    2009-01-01

    The Retsof salt mine in upstate New York was flooded from 1994 to 1996 after two roof collapses created rubble chimneys in overlying bedrock that intersected a confined aquifer in glacial sediments. The mine now contains about 60 billion liters of saturated halite brine that is slowly being displaced as the weight of overlying sediments causes the mine cavity to close, a process that could last several hundred years. Saline water was detected in the confined aquifer in 2002, and a brine-mitigation project that includes pumping followed by onsite desalination was implemented in 2006 to prevent further migration of saline water from the collapse area. A study was conducted by the U.S. Geological Survey using geochemical and variable-density flow modeling to determine sources of salinity in the confined aquifer and to assess (1) processes that control movement and mixing of waters in the collapse area, (2) the effect of pumping on salinity, and (3) the potential for anhydrite dissolution and subsequent land subsidence resulting from mixing of waters induced by pumping. The primary source of salinity in the collapse area is halite brine that was displaced from the flooded mine and transported upward by advection and dispersion through the rubble chimneys and surrounding deformation zone. Geochemical and variable-density modeling indicate that salinity in the upper part of the collapse area is partly derived from inflow of saline water from bedrock fracture zones during water-level recovery (January 1996 through August 2006). The lateral diversion of brine into bedrock fracture zones promoted the upward migration of mine water through mixing with lower density waters. The relative contributions of mine water, bedrock water, and aquifer water to the observed salinity profile within the collapse area are controlled by the rates of flow to and from bedrock fracture zones. Variable-density simulations of water-level recovery indicate that saline water has probably not

  18. Deposition of talc - kerolite-smectite - smectite at seafloor hydrothermal vent fields: Evidence from mineralogical, geochemical and oxygen isotope studies

    Science.gov (United States)

    Dekov, V.M.; Cuadros, J.; Shanks, Wayne C.; Koski, R.A.

    2008-01-01

    Talc, kerolite-smectite, smectite, chlorite-smectite and chlorite samples from sediments, chimneys and massive sulfides from six seafloor hydrothermal areas have been analyzed for mineralogy, chemistry and oxygen isotopes. Samples are from both peridotite- and basalt-hosted hydrothermal systems, and basaltic systems include sediment-free and sediment-covered sites. Mg-phyllosilicates at seafloor hydrothermal sites have previously been described as talc, stevensite or saponite. In contrast, new data show tri-octahedral Mg-phyllosilicates ranging from pure talc and Fe-rich talc, through kerolite-rich kerolite-smectite to smectite-rich kerolite-smectite and tri-octahedral smectite. The most common occurrence is mixed-layer kerolite-smectite, which shows an almost complete interstratification series with 5 to 85% smectitic layers. The smectite interstratified with kerolite is mostly tri-octahedral. The degree of crystal perfection of the clay sequence decreases generally from talc to kerolite-smectite with lower crystalline perfection as the proportion of smectite layers in kerolite-smectite increases. Our studies do not support any dependence of the precipitated minerals on the type/subtype of hydrothermal system. Oxygen isotope geothermometry demonstrates that talc and kerolite-smectite precipitated in chimneys, massive sulfide mounds, at the sediment surface and in open cracks in the sediment near seafloor are high-temperature (> 250????C) phases that are most probably the result of focused fluid discharge. The other end-member of this tri-octahedral Mg-phyllosilicate sequence, smectite, is a moderate-temperature (200-250????C) phase forming deep within the sediment (??? 0.8??m). Chlorite and chlorite-smectite, which constitute the alteration sediment matrix around the hydrothermal mounds, are lower-temperature (150-200????C) phases produced by diffuse fluid discharge through the sediment around the hydrothermal conduits. In addition to temperature, other two

  19. Rediscovery and Exploration of Magic Mountain, Explorer Ridge, NE Pacific

    Science.gov (United States)

    Embley, R. W.

    2002-12-01

    either centered within the neovolcanic zone or associated with a boundary fault. The active venting occurs over at least 400 m along axis and is mostly concentrated in clusters of high temperature chimneys, each about 50 m in diameter. Two of these clusters have a basal sulfide mound. There is obvious structural control of many of the vents - many lie along or in line with distinct fissures or small faults and the entire field appears to have developed within a shallow graben formed on the ridge flank. Most of the chimneys consist of relatively friable sulfates (barite/anhydrite) that vent clear fluid at up to about 290°C. Several larger active chimneys consist primarily of sulfide minerals that emit gray smoke with temperatures as high as 312§ C. Biologic communities were primarily associated with the more stable sulfide structures. The mixture of proven technology used from a capable surface vessel during the 2002 Explorer Ridge program, including a cutting edge deep AUV and a large ROV, provided the tools to explore a little-known site at a full range of scales in a short amount of time and collect invaluable samples for research. These initial data sets from the 2002 exploration program set the stage for more detailed studies of this unique hydrothermal system in the future.

  20. Hydrothermal Vents at 5000m on the Mid-Cayman Rise: The Deepest and Hottest Hydrothermal Systems Yet Discovered!

    Science.gov (United States)

    Murton, B. J.; Connelly, D. P.; Copley, J. T.; Stansfield, K. L.; Tyler, P. A.; Cruise Jc044 Sceintific Party

    2010-12-01

    This contribution describes the geological setting of hydrothermal activity within the Mid- Cayman Rise (MCR) using data acquired during cruise JC044 (MAR-APR 2010) from the deep-towed sidescan sonar TOBI, AUV Autosub6000 and the ROTV HyBIS. The 110 km-long Mid- Cayman Rise (MCR), located within Caribbean Sea, is the deepest spreading centre known, reaching over 6000m. Hence it poses an end-member of extreme depth for hydrothermal circulation. Accretion of new volcanic crust is focused within two ridge segments, to the north and south of a centrally located massif of peridotite and gabbro. Following earlier indications of hydrothermal plumes (German et al., in 2009), we discovered two high-temperature hydrothermal system: one at a depth of 5000m in the neovolcanic zone of the northern segment, and another at 2300m on the flanks of the MCR. These sites show contrasting styles of fluid venting, mineralisation, geological setting and host rock interaction. At 5000m-depth, the ultra-deep vent site forms the deepest hydrothermal system known. Venting is focused at the western side of a 100m diameter, 30m high mound, while inactive sulphides extend eastwards for at least 800m. Fluids discharge from clusters of chimneys whose location is related to basement faults. Changes in salinity in the venting fluids indicate discharge of a low salinity phase and a brine phase. At 500bar, this is definitive evidence for supercritical fluid emission. We also found the sulphide mineralization to be copper-rich, giving a characteristic green hue to many of the deposits, probably a result of the super-critical state of the vent fluids. A prominent axial volcanic ridge nearby indicates a robust magma supply to the northern MCR segment. Thus it is likely the ultra-deep vent site derives its thermal energy from magmatic sources, similar to those thought to underlie other slow-spreading ridge volcanic-hosted vent sites (e.g. Broken Spur: MAR). The shallower (2300m) MCR hydrothermal vent