Industrial chimney monitoring - contemporary methods

Science.gov (United States)

Kaszowska, Olga; Gruchlik, Piotr; Mika, Wiesław

2018-04-01

The paper presents knowledge acquired during the monitoring of a flue-gas stack, performed as part of technical and scientific surveillance of mining activity and its impact on industrial objects. The chimney is located in an area impacted by mining activity since the 1970s, from a coal mine which is no longer in existence. In the period of 2013-16, this area was subject to mining carried out by a mining entrepreneur who currently holds a license to excavate hard coal. Periodic measurements of the deflection of the 113-meter chimney are performed using conventional geodetic methods. The GIG used 3 methods to observe the stack: landbased 3D laser scanning, continuous deflection monitoring with a laser sensor, and drone-based visual inspections. The drone offered the possibility to closely inspect the upper sections of the flue-gas stack, which are difficult to see from the ground level.

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

Analysis of Foundation of Tall R/C Chimney Incorporating Flexibility of Soil

Science.gov (United States)

Jayalekshmi, B. R.; Jisha, S. V.; Shivashankar, R.

2017-09-01

Three dimensional Finite Element (FE) analysis was carried out for 100 and 400 m high R/C chimneys having piled annular raft and annular raft foundations considering the flexibility of soil subjected to across-wind load. Stiffness of supporting soil and foundation were varied to evaluate the significance of Soil-Structure Interaction (SSI). The integrated chimney-foundation-soil system was analysed by finite element software ANSYS based on direct method of SSI assuming linear elastic material behaviour. FE analyses were carried out for two cases of SSI namely, (1) chimney with annular raft foundation and (2) chimney with piled annular raft foundation. The responses in raft such as bending moments and settlements were evaluated for both the cases and compared to those obtained from the conventional method of analysis of annular raft foundation. It is found that the responses in raft vary considerably depending on the stiffness of the underlying soil and the stiffness of foundation. Piled raft foundations are better suited for tall chimneys to be constructed in loose or medium sand.

Research on gas transport in chimneys: a progress report

International Nuclear Information System (INIS)

Hearst, J.R.

1986-01-01

The results of the AGRINI and TIERRA experiments have led us to study three general topics: collapse phenomenology, CO 2 content measurement, and gas transport in chimneys. Our results so far are fragmentary, but we have been able to come to some tentative conclusions: (1) a layer of strong material between depths of 24 and 32 m, and perhaps some relatively strong material deeper, may have caused the AGRINI crater shape. This layer was absent at the nearby LABAN and CROWDIE events. We were unable to locate the layer with a surface penetrometer or surface seismic methods, but it may be possible to measure strength vs depth in situ by examining the penetration depth of a projectile. (2) We can probably improve our knowledge of the in situ CO 2 content by calibrating a commercial carbon/oxygen logging system for NTS conditions. (3) It is possible to measure the response of the gas in a chimney to changes in atmospheric pressure. There can be significantly different gas transport in chimneys with the same pressure response, depending on the porosity and the distribution of the porosity. It is possible to perform an inexpensive experiment to study the gas transport in an existing chimney

Industrial chimney monitoring - contemporary methods

Directory of Open Access Journals (Sweden)

Kaszowska Olga

2018-01-01

Full Text Available The paper presents knowledge acquired during the monitoring of a flue-gas stack, performed as part of technical and scientific surveillance of mining activity and its impact on industrial objects. The chimney is located in an area impacted by mining activity since the 1970s, from a coal mine which is no longer in existence. In the period of 2013-16, this area was subject to mining carried out by a mining entrepreneur who currently holds a license to excavate hard coal. Periodic measurements of the deflection of the 113-meter chimney are performed using conventional geodetic methods. The GIG used 3 methods to observe the stack: landbased 3D laser scanning, continuous deflection monitoring with a laser sensor, and drone-based visual inspections. The drone offered the possibility to closely inspect the upper sections of the flue-gas stack, which are difficult to see from the ground level.

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.

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)

Optimization of a combined solar chimney for desalination and power generation

International Nuclear Information System (INIS)

Asayesh, Mohammad; Kasaeian, Alibakhsh; Ataei, Abtin

2017-01-01

Highlights: • One dimensional code is developed for simulation of a hybrid solar chimney. • The code is validated using experimental data of a simple solar chimney. • Partial coverage of the collector area by the desalination system is more beneficial. • The optimal configuration of the combined system is found using PSO algorithm. - Abstract: Large footprint and very low efficiency are main disadvantages of solar chimneys. To resolve this, solar desalination system has been added under the collector of a solar chimney power plant. Generally the collector ground is completely covered by the desalination pond but here it is shown that more benefit can be achieved by partial occupation of the collector area. This is performed by implementing the particle swarm optimization (PSO) algorithm in conjunction with a one dimensional simulation code. The code is first validated using data of a laboratory scale solar chimney. Then, optimization results show that for a collector diameter of 250 m and tower height of 200 m, a solar pond located between radii 85 and 125 m of the collector can maximize the outcome of the combined system. Generally, dimensions of the desalination system depend on local cost of building the system and price of electricity and fresh water produced.

Numerical analysis on the performance of solar chimney power plant system

International Nuclear Information System (INIS)

Xu Guoliang; Ming Tingzhen; Pan Yuan; Meng Fanlong; Zhou Cheng

2011-01-01

Power generating technology based on renewable energy resources will definitely become a new trend of future energy utilization. Numerical simulations on air flow, heat transfer and power output characteristics of a solar chimney power plant model with energy storage layer and turbine similar to the Spanish prototype were carried out in this paper, and mathematical model of flow and heat transfer for the solar chimney power plant system was established. The influences of solar radiation and pressure drop across the turbine on the flow and heat transfer, output power and energy loss of the solar chimney power plant system were analyzed. The numerical simulation results reveal that: when the solar radiation and the turbine efficiency are 600 W/m 2 and 80%, respectively, the output power of the system can reach 120 kW. In addition, large mass flow rate of air flowing through the chimney outlet become the main cause of energy loss in the system, and the collector canopy also results in large energy loss.

Experimental and numerical analysis of pollutant dispersion from a chimney

Energy Technology Data Exchange (ETDEWEB)

Said, N.M.; Mhiri, H. [Ecole Nationale d' Ingenieurs de Monastir, Tunisie (Tunisia). Laboratorie de Mecanique des Fluides et Thermique; Le Palec, G.; Bournot, P. [UNIMECA, Marseille (France). Institut de Mecanique de Marseille, Equipe IMFT

2005-03-01

Particle image velocimetry (PIV) is used to extract and characterize the underlying organized motions, i.e. coherent structures, within the near-wake region of a turbulent round jet discharged perpendicularly from a chimney into a crossflow. This flow has been found to be quite complex owing to its three-dimensional nature and the interactions between several flow regions. Analyses of the underlying coherent structures, which play an important role in the physics of the flow, are still rare and mostly based on flow-visualization techniques. Using a PIV technique, we examined the wake regions of the chimney and plume at levels near the top of the chimney. The complex geometry of these structures in the wake of the plume as well as their interaction with the plume as it bends over after emission is discussed. In this paper we describe the Kelvin-Helmholtz vortex structures, the downwash phenomena and the effect of the height of the chimney. Extensive wind tunnel experimental results are presented and compared with numerical simulation. A good level of agreement was found between the results of flow visualization and numerical simulation. (author)

29 CFR 1926.854 - Removal of walls, masonry sections, and chimneys.

Science.gov (United States)

2010-07-01

..., girders, and similar structural supports shall be cleared of all loose material as the masonry demolition... 29 Labor 8 2010-07-01 2010-07-01 false Removal of walls, masonry sections, and chimneys. 1926.854....854 Removal of walls, masonry sections, and chimneys. (a) Masonry walls, or other sections of masonry...

Computational studies on the effect of geometric parameters on the performance of a solar chimney power plant

International Nuclear Information System (INIS)

Patel, Sandeep K.; Prasad, Deepak; Ahmed, M. Rafiuddin

2014-01-01

Graphical abstract: This work is aimed at optimizing the geometry of the major components of a solar chimney power plant using ANSYS-CFX. The collector inlet opening, collector height, collector outlet diameter, the chimney throat diameter and the chimney divergence angle were varied for the same chimney height and collector diameter and the performance of the plant was studied in terms of the available power and an optimum configuration was obtained. The temperature and velocity variations in the collector and along the chimney height were also studied. - Highlights: • Geometry of the major components of a solar chimney power plant optimized using CFX. • Collector inlet opening, height, outlet diameter, chimney throat diameter, and the chimney divergence angle were varied. • Temperature and velocity variations and available power were obtained for different configurations. • Optimum values of collector outlet height and diameter and the divergence angle were obtained. - Abstract: A solar chimney power plant (SCPP) is a renewable-energy power plant that transforms solar energy into electricity. The SCPP consists of three essential elements – solar air collector, chimney tower, and wind turbine(s). The present work is aimed at optimizing the geometry of the major components of the SCPP using a computational fluid dynamics (CFD) software ANSYS-CFX to study and improve the flow characteristics inside the SCPP. The overall chimney height and the collector diameter of the SCPP were kept constant at 10 m and 8 m respectively. The collector inlet opening was varied from 0.05 m to 0.2 m. The collector outlet diameter was also varied from 0.6 m to 1 m. These modified collectors were tested with chimneys of different divergence angles (0°–3°) and also different chimney inlet openings of 0.6 m to 1 m. The diameter of the chimney was also varied from 0.25 m to 0.3 m. Based on the CFX computational results, the best configuration was achieved using the chimney

Seismic decoupling of an explosion centered in a granite chimney rubble -- scaled experiment results. Final report

Energy Technology Data Exchange (ETDEWEB)

Keller, C. [Science & Engineering Associates, Inc., Santa Fe, NM (United States); Miller, S.; Florence, A.; Fogle, M.; Kilb, D.

1991-12-01

This report describes the small scale evaluation of the feasibility of significant decoupling by siting an explosion in granite rubble. The chimney characteristics scaled to laboratory dimensions were those of the PILE DRIVER event. The scaled charges were of 1 KT and 8KT in the PILE DRIVER chimney. The measure of the effect was the velocity field history in the granite outside the chimney volume with the chimney rubble and with no rubble. A number of chimney sizes and shapes were studied. The explosion process was modeled via two-din=mensional, finite-difference methods used for prediction of velocity histories at the Nevada Test Site. The result was that both the spectral shape and the magnitude of the transmitted shock wave were drastically altered. The chimney geometry was as important as the rubble characteristics.

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)

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

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jeong Soo; Cho, Yeong Garp; Lee, Jung Hee; Jung, Hoan Sung; Seo, Choon Gyo; Shin, Jin Won

2007-12-15

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 {approx} 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

Vibration test report for in-chimney bracket and instrumented fuel assembly

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jeong Soo; Yoon, D. B.; Cho, Y. G.; Ahn, G. H.; Lee, J. H.; Park, J.H

2000-10-01

The vibration levels of in-chimney bracket structure which is installed in reactor chimney and instrumented fuel assembly(Type-B Bundle) are investigated under the steady state normal operating condition of the reactor. For this purpose, 4 acceleration data on the guide tube of the instrumented fuel assembly and in-chimney bracket structures subjected to fluid induced vibration are measured. For the analysis of the vibration data, vibration analysis program which can perform basic time and frequency domain analysis, is prepared, and its reliability is verified by comparing the analysis results with those of commercial analysis program(I-DEAS). In time domain analysis, maximum amplitudes, and RMS values of accelerations and displacements from the measured vibration signal, are obtained. The frequency components of the vibration data are analyzed by using the frequency domain analysis. These analysis results show that the levels of the measured vibrations are within the allowable level, and the low frequency component near 10 Hz is dominant in the vibration signal. For the evaluation of the structural integrity on the in-chimney bracket and related structures including the instrumented fuel assembly, the static analysis for ANSYS finite element model is carried out. These analysis results show that the maximum stresses are within the allowable stresses of the ASME code, and the maximum displacement of the top of the flow tube is within the displacement limit. Therefore any damage on the structural integrity is not expected when the irradiation test is performed using the in-chimney bracket.

Vibration test report for in-chimney bracket and instrumented fuel assembly

International Nuclear Information System (INIS)

Ryu, Jeong Soo; Yoon, D. B.; Cho, Y. G.; Ahn, G. H.; Lee, J. H.; Park, J.H.

2000-10-01

The vibration levels of in-chimney bracket structure which is installed in reactor chimney and instrumented fuel assembly(Type-B Bundle) are investigated under the steady state normal operating condition of the reactor. For this purpose, 4 acceleration data on the guide tube of the instrumented fuel assembly and in-chimney bracket structures subjected to fluid induced vibration are measured. For the analysis of the vibration data, vibration analysis program which can perform basic time and frequency domain analysis, is prepared, and its reliability is verified by comparing the analysis results with those of commercial analysis program(I-DEAS). In time domain analysis, maximum amplitudes, and RMS values of accelerations and displacements from the measured vibration signal, are obtained. The frequency components of the vibration data are analyzed by using the frequency domain analysis. These analysis results show that the levels of the measured vibrations are within the allowable level, and the low frequency component near 10 Hz is dominant in the vibration signal. For the evaluation of the structural integrity on the in-chimney bracket and related structures including the instrumented fuel assembly, the static analysis for ANSYS finite element model is carried out. These analysis results show that the maximum stresses are within the allowable stresses of the ASME code, and the maximum displacement of the top of the flow tube is within the displacement limit. Therefore any damage on the structural integrity is not expected when the irradiation test is performed using the in-chimney bracket

D0 - Chimney Lead Quench Detection, Beta Solenoid

International Nuclear Information System (INIS)

Visser, A.T.

1993-01-01

The voltage drop across the superconducting chimney lead is sensed to detect a quench. The return sense lead is mounted outside the chimney. The return sense lead and the superconducting chimney wire form a loop with area A ∼ 1.7 m 2 (information from R. Ru. cinski). Changing flux through area A will induce a voltage in the sense loop and could cause false quench detection. Assume that the field through A changes 1 kGauss (0.1 Wb/m 2 ) in 10 -3 sec. The induced voltage is then: e = d0/dt = dBA/dt and e = 0.1 x 1.7/10 -3 = 170 V. This is probably a very pessimistic estimate, but it shows that we have to watch out. Changes of 100 Gauss in 100 msec (CDF experience?) are probably more likely and cause: e = 0.01 x 1.7/10 -2 ∼ 1.7 V noise. This noise is still too high because trip levels are planned to sit at ∼50 mV? It is practically impossible to predict what the real noise values would be, but I expect them to be in the order of 1 to 10 V. This is more than we can handle and I would expect nuisance trips.

Optimizing of solar chimney performance using electrohydrodynamic system based on array geometry

International Nuclear Information System (INIS)

Ghalamchi, Mehrdad; Kasaeian, Alibakhsh; Ghalamchi, Mehran; Fadaei, Niloufar; Daneshazarian, Reza

2017-01-01

Highlights: • Three different electrohydrodynamic layouts are applied in the solar chimney pilot. • Effective parameters of electrohydrodynamic is represented in every layout. • The air velocity and heat transfer were increased outstandingly. • The temperature distribution in the absorber surface and the fluid is investigated. • The performance and the efficiency of the solar chimney pilot are increased. - Abstract: The effect of the electrohydrodynamic system with various electrode layouts on a solar chimney pilot is investigated experimentally. A pilot setup was constructed which consisted of a chimney with 3 m height and 3 m collector diameter. The purpose of this research was to enhance the solar chimney performance with the electrohydrodynamic system for the parallel, radial, and symmetric layouts. By using of corona wind, the outlet fluid temperature is increased, and the outlet absorber is decreased. For the three layouts, the most growth in the outlet fluid temperature is 14 °C, which is observed in the parallel layout. Also, in the parallel array, the most outlet absorber temperature drop is 7 °C. The results show that parallel layout with six electrodes and 3 cm spacing between the electrodes has the best performance. Also, various hours of the day are studied and the best time for turning on the electrohydrodynamic system is 1:00 p.m. The electrohydrodynamic system makes an increase in the fluid velocity from 1.7 to 2.3 m s −1 , and this growth improves the performance about 28%.

Value and limitations of chimney grafts to treat arch lesions.

Science.gov (United States)

Mangialardi, N; Ronchey, S; Malaj, A; Fazzini, S; Alberti, V; Ardita, V; Orrico, M; Lachat, M

2015-08-01

The endovascular debranching with chimney stents provides a minimally invasive alternative to open surgery with readily available devices and has extended the option of endoluminal therapy into the realm of the aortic arch. But a critical observation at the use of this technique at the aortic arch is important and necessary because of the lack of long-term results and long term patency of the stents. Our study aims to review the results of chimney grafts to treat arch lesions. A systematic health database search was performed in December 2014 according to the Prisma Guidelines. Papers were sought through a meticulous search of the MEDLINE database (National Library of Medicine, Bethesda, MA) using the Pubmed search engine. Twenty-two articles were eligible for detailed analysis and data extraction. A total of 182 patients underwent chimney techniques during TEVAR (Thoracic Endovascular Aneurysm Repair). A total of 217 chimney grafts were implanted: 36 to the IA, 1 to the RCCA, 91 to the LCCA and 89 to the LSA. The type of stent-graft used for TEVAR was described in 132 patients. The type and name of chimney graft was described in 126 patients. In 53 patients information was limited to the type. Primary technical success, defined as a complete chimney procedure was achieved in 171 patients (98%). In 8 patients it was not clearly reported. The overall stroke rate was 5.3%. The overall endoleak rate, in those papers were it was clearly reported, was 18.4% (31 patients); 23(13,6%) patients developed a type IA endoleak, 1 patient (0.6%) developed type IB endoleak and 7 patients (4.1%) developed a type II endoleak The total endovascular aortic arch debranching technique represent a good option to treat high-risk patients, because it dramatically reduces the aggressiveness of the procedure in the arch. Many concerns are still present, mainly related to durability and material interaction during time. Long-term follow-up is exceptionally important in light of the

Design and measured performance of a solar chimney for natural-circulation solar-energy dryers

International Nuclear Information System (INIS)

Ekechukwu, O.V.; Norton, B.

1995-10-01

The design and construction of a solar chimney which was undertaken as part of a study on natural-circulation solar-energy dryers is reported. The experimental solar chimney consists of a 5.3m high and 1.64m diameter cylindrical polyethylene-clad vertical chamber, supported structurally by steel framework and draped internally with a selectively-absorbing surface. The performance of the chimney which was monitored extensively with and without the selective surface in place (to study the effectiveness of this design option) is also reported. (author). 14 refs, 7 figs

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.

The Canadian residential duct and chimney survey

Energy Technology Data Exchange (ETDEWEB)

Fugler, D.

2003-12-01

A study was conducted in 1989 to better understand the thermal performance of ducts and chimneys in houses. The objective was to address the problems associated with insufficient airflow and backdrafting of combustion gases resulting from malfunctioning fans, furnaces and fireplaces. The Duct Test Rig was used to measure and recorded airflows and heat losses in a variety of ducts and chimneys in a representative mix of houses in Vancouver, Kelowna, Winnipeg, Calgary, Toronto, London, Montreal, Quebec City, Halifax, Fredericton and Ottawa. Bath, kitchen, clothes dryer and central vacuum exhaust fans were tested to determine how performance is affected by fan age, accumulations of dust, grease, bugs and installation methods. Results indicate that there is no statistical difference between axial or centrifugal fans. The greatest problem appeared to be with low flows, high leakage rates, and poor conditions of bathroom fans. Many kitchen fans were found to be blocked at the inlet by cooking grease. The exhaust flows depended greatly on the condition of the backdraft damper. Dryer exhaust airflow was typically less than the 75 L/s specified by manufacturers, but even old dryers performed relatively well. All types of chimneys were tested for different positive hood pressures, airflow lost through leakage, and thermal characteristics. Airflow was found to vary depending on the type and area of the flue and the presence of a cap. For heating systems, the low duct efficiency was due mostly to duct leakage, radiation losses and restrictive ducts and registers. The findings of this testing program are still valid today. 3 tabs.

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.

Preliminary work for stage 2 decommissioning of B16 pile chimney

International Nuclear Information System (INIS)

Wright, E.M.; Mathews, R.F.

1991-01-01

Planning of the second stage of decommissioning of the two pile chimneys at Sellafield started while work was underway on the first stage, which involved removal of the sections above the filters. The second stage requires the removal of all radio-active parts and the dismantling of the filter and diffuser sections, and has to be completed by 1997. The planning involved studying the many possible options and their effects on both radiological and industrial safety. This decommissioning project employs a high proportion of civil engineering and construction techniques, which are then developed to eliminate the hazards from radioactive dusts, and to minimise the effect of radiation on operatives working on the project. Much of this equipment is modified forms of standard construction equipment and includes cutting equipment and remotely operated vehicles. The initial phases of the work involve: provision of a waste packaging and access building; provision of temporary ventilation systems to control the dust generated by the work, cutting of 3 m square access doorway through the 1.5 m thick reinforced concrete wall of the chimney; provision of Remotely Operated Vehicle (ROV) to act as a tool carrier for lining stripping work; removal of the thermal lining from the floor and lower walls of the chimney, and installation of precast concrete walls which separate the pile reactor core from the chimney flue. (author)

Economic analysis of power generation from floating solar chimney power plant

International Nuclear Information System (INIS)

Zhou, Xinping; Yang, Jiakuan; Xiao, Bo; Wang, Fen

2009-01-01

Solar chimney thermal power technology that has a long life span is a promising large-scale solar power generating technology. This paper performs economic analysis of power generation from floating solar chimney power plant (FSCPP) by analyzing cash flows during the whole service period of a 100 MW plant. Cash flows are influenced by many factors including investment, operation and maintenance cost, life span, payback period, inflation rate, minimum attractive rate of return, non-returnable subsidy rate, interest rate of loans, sale price of electricity, income tax rate and whether additional revenue generated by carbon credits is included or not. Financial incentives and additional revenue generated by carbon credits can accelerate the development of the FSCPP. Sensitivity analysis to examine the effects of the factors on cash flows of a 100 MW FSCPP is performed in detail. The results show that the minimum price for obtaining minimum attractive rate of return (MARR) of 8% reaches 0.83 yuan (kWh) -1 under financial incentives including loans at a low interest rate of 2% and free income tax. Comparisons of economics of the FSCPP and reinforced concrete solar chimney power plant or solar photovoltaic plant are also performed by analyzing their cash flows. It is concluded that FSCPP is in reality more economical than reinforced concrete solar chimney power plant (RCSCPP) or solar photovoltaic plant (SPVP) with the same power capacity. (author)

[Negligent homicide caused by exhaust gas escaping from a manipulated chimney].

Science.gov (United States)

Wirth, Ingo; Varchmin-schultheiss, Karin; Schmeling, Andreas

2011-01-01

A chimney built and operated according to the instructions is supposed to ensure that the combustion gases coming from the fireplace can escape safely. If the operational reliability is impaired, this presents a risk of acute poisoning. The report deals with a negligently caused carbon monoxide poisoning of a married couple as a consequence of improper installation of a cover of the chimney opening. Various causes of fatal poisoning due to defective exhaust systems are discussed in connection with the presented case report.

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.

Analysis of Solar Chimneys in Different Climate Zones - Case of Social Housing in Ecuador

Science.gov (United States)

Godoy-Vaca, Luis; Almaguer, Manuel; Martínez-Gómez, Javier; Lobato, Andrea; Palme, Massimo

2017-10-01

The aim of this research is to simulate the performance of a solar chimney located in different macro-zones in Ecuador. The proposed solar chimney model was simulated using a python script in order to predict the temperature distribution and the mass flow over time. The results obtained were firstly compared with experimental data for dry-warm climate. Then, the model was evaluated and tested in real weather conditions: dry-warm, moist-warm and rainy-cold. In addition, the assumed chimney dimensions were chosen according to the literature for the studied conditions. In spite of evaluating the best nightly ventilation, different chimney wall materials were tested: solid brick, common brick and reinforced concrete. The results showed that concrete in a dry-warm climate, a metallic layer on the gap with solid brick in a moist-warm climate and reinforced concrete in a rainy cold climate used for the absorbent wall improve the thermal inertia of the social housing.

Validation experiments of the chimney model for the operational simulation of hydrogen recombiners

International Nuclear Information System (INIS)

Simon, Berno

2013-01-01

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.

Hemodynamic and Anatomic Predictors of Renovisceral Stent-Graft Occlusion Following Chimney Endovascular Repair of Juxtarenal Aortic Aneurysms.

Science.gov (United States)

Tricarico, Rosamaria; He, Yong; Laquian, Liza; Scali, Salvatore T; Tran-Son-Tay, Roger; Beck, Adam W; Berceli, Scott A

2017-12-01

To identify anatomic and hemodynamic changes associated with impending visceral chimney stent-graft occlusion after endovascular aneurysm repair (EVAR) with the chimney technique (chEVAR). A retrospective evaluation was performed of computed tomography scans from 41 patients who underwent juxtarenal chEVAR from 2008 to 2012 to identify stent-grafts demonstrating conformational changes following initial placement. Six subjects (mean age 74 years; 3 men) were selected for detailed reconstruction and computational hemodynamic analysis; 4 had at least 1 occluded chimney stent-graft. This subset of repairs was systematically analyzed to define the anatomic and hemodynamic impact of these changes and identify signature patterns associated with impending renovisceral stent-graft occlusion. Spatial and temporal analyses of cross-sectional area, centerline angle, intraluminal pressure, and wall shear stress (WSS) were performed within the superior mesenteric and renal artery chimney grafts used for repair. Conformational changes in the chimney stent-grafts and associated perturbations, in both local WSS and pressure, were responsible for the 5 occlusions in the 13 stented branches. Anatomic and hemodynamic signatures leading to occlusion were identified within 1 month postoperatively, with a lumen area 25 Pa/mm (p=0.03), and systolic WSS >45 Pa (p=0.03) associated with future chimney stent-graft occlusion. Chimney stent-grafts at increased risk for occlusion demonstrated anatomic and hemodynamic signatures within 1 month of juxtarenal chEVAR. Analysis of these parameters in the early postoperative period may be useful for identifying and remediating these high-risk stent-grafts.

Hydrologic processes and radionuclide distribution in a cavity and chimney produced by the Cannikin nuclear explosion, Amchitka Island, Alaska

International Nuclear Information System (INIS)

Claassen, H.C.

1978-01-01

An analysis of hydraulic, chemical, and radiochemical data obtained in the vicinity of the site of a nuclear explosion (code-named Cannikin, 1971), on Amchitka Island, Alaska, was undertaken to describe the hydrologic processes associated with the saturation of subsurface void space produced by the explosion. Immediately after detonation of the explosive, a subsurface cavity was created surrounding the explosion point. This cavity soon was partly filled by collapse of overburden, producing void volume in a rubble chimney extending to land surface and forming a surface-collapse sink. Surface and groundwater immediately began filling the chimney but was excluded for a time from the cavity by the presence of steam. When the steam condensed, the accumulated water in the chimney flowed into the cavity region, picking up and depositing radioactive materials along its path. Refilling of the chimney voids then resumed and was nearly complete about 260 days after the explosion. The hydraulic properties of identified aquifers intersecting the chimney were used with estimates of surface-water inflow, chimney dimensions, and the measured water-level rise in the chimney to estimate the distribution of explosion-created porosity in the chimney, which ranged from about 10 percent near the bottom to 4 percent near the top. Chemical and radiochemical analyses of water from the cavity resulted in identification of three aqueous phases: groundwater, surface water, and condensed steam. Although most water samples represented mixtures of these phases, they contained radioactivity representative of all radioactivity produced by the explosion

Continuous In Situ Measurements of Near Bottom Chemistry and Sediment-Water Fluxes with the Chimney Sampler Array (CSA)

Science.gov (United States)

Martens, C. S.; Mendlovitz, H. P.; White, B. L.; Hoer, D.; Sleeper, K.; Chanton, J.; Wilson, R.; Lapham, L.

2011-12-01

The Chimney Sampler Array (CSA) was designed to measure in situ chemical and physical parameters within the benthic boundary layer plus methane and oxygen sediment-water chemical fluxes at upper slope sites in the northern Gulf of Mexico. The CSA can monitor temporal changes plus help to evaluate oceanographic and sub-seafloor processes that can influence the formation and stability of gas hydrates in underlying sediments. The CSA consists of vertical cylinders (chimneys) equipped with internal chemical sensors and with laboratory flume-calibrated washout rates. Chimney washout rates multiplied by chimney mean versus ambient concentrations allow calculation of net O2 and methane sediment-water fluxes. The CSA is emplaced on the seafloor by a ROVARD lander using a ROV for chimney deployments. The CSA presently includes two 30 cm diameter by 90 cm length cylinders that seal against the sediment with lead pellet beanbags; within each chimney cylinder are optode, conductivity and methane sensors. The CSA's data logger platform also includes pressure and turbidity sensors external to the chimneys along with an acoustic Doppler current meter to measure temporal variation in ambient current velocity and direction. The CSA was deployed aboard a ROVARD lander on 9/13/2010 in the northern Gulf of Mexico (Lat. 28 51.28440, Long. 088 29.39421) on biogeochemically active sediments within Block MC-118. A ROV was utilized for chimney deployment away from the ROVARD lander. The CSA monitored temporal changes in water column physical parameters, obtained near-bottom chemical data to compare with pore fluid and sediment core measurements and measured temporal variability in oxygen and methane sediment-water fluxes at two closely spaced stations at MC-118. A continuous, three-week data set was obtained that revealed daily cycles in chemical parameters and episodic flux events. Lower than ambient chimney dissolved O2 concentrations controlled by temporal variability in washout rates

Evaluation of a stack: A concrete chimney with brick liner

International Nuclear Information System (INIS)

Joshi, J.R.; Amin, J.A.; Porthouse, R.A.

1995-01-01

A 200 ft. tall stack, consisting of a concrete chimney with an independent acid proof brick liner built in the 1950's, serving the Separations facility at the Savannah River Site (SRS), was evaluated for the performance category 3 (PC3) level of Natural Phenomena Hazards (NPH) effects. The inelastic energy absorption capacity of the concrete chimney was considered in the evaluation of the earthquake resistance, in particular, to compute the F μ factor. The calculated value of F μ exceeded 3.0, while the seismic demand for the PC3 level, using an F μ value of 1.5, was found to be less than the capacity of the concrete chimney. The capacity formulation of ACI 307 was modified to incorporate the effect of an after design opening on the tension side. There are considerable uncertainties in determining the earthquake resistance of the independent brick liner. The critical liner section, located at the bottom of the breeching opening, does not meet the current recommendations. A discussion is provided for the possible acceptable values for the ''Moment Reduction Factor'', R w or F μ for the liner. Comments are provided on the comparison of stack demands using response spectra (RS) versus time history (TH) analysis, with and without soil structure interaction (SSI) effects

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.

Hydrothermal chimneys and Sulphide mineralised breccias from the Kolbeinsey and the Mohns Ridge

Science.gov (United States)

Nygård, T. E.; Bjerkgård, T.; Kelly, D.; Thorseth, I.; Pedersen, R. B.

2003-04-01

An inactive hydrothermal ventsite was discovered at the Kolbeinsey Ridge, (68^o56'N,17^o12'W) during the SUBMAR-99 cruise. The field is located in the neovolcanic sone at the flat top of a circular volcano at 900 m water depth. Two major fields contain about 30 chimneys. The top of one chimney was collected for further research. The mineralogy of the chimney is dominated by sphalerite, silica and barite, with minor amounts of galena and pyrrhotite, an assemblage which suggest a formation temperature white smokers [1]. The outer part of the chimney is enriched in LREE and shows a large positive Eu-anomaly compared to the inner parts of the chimney. Variation in Ce-anomaly reflects varying degrees of seawater infiltration during mineral precipitation. The first formed minerals in the lower part, and the outer part of the chimney appears to contain the most seawater-affected minerals. The Ag content of sphalerite may be as high as 1 wt%, but is restricted to small domains especially around fluid channels. A zonation in the Fe/Zn ratio of sphalerite is observed across fluid channels, suggesting variations in the fluid composition with time. The Pb-content of the chimney is extremely high, with up to 10 wt% in some sphalerite grains, and the bulk values are as high as 10 000 ppm. These high values suggest that sediments may have been present in the reaction zone of this hydrothermal system. Sulphide mineralised breccias were recovered by dredging the northern fault wall of the Mohns Ridge at 72^o39,33'N, 02^o40,87'E, during the SUBMAR-2000 cruise. The breccias exhibit several progressive stages of hydrothermal alteration: 1) the least altered parts are composed of partly altered basalt clasts and some chlorite, 2) more strongly altered samples mainly consist of quarts in a chlorite matrix, 3) and the most heavily mineralised parts contain secondary quarts and chalcopyrite. The final hydrothermal stage recorded by the breccias involved oxidation of chalcopyrite and

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.

Seismic chimneys in the Southern Viking Graben - Implications for palaeo fluid migration and overpressure evolution

Science.gov (United States)

Karstens, Jens; Berndt, Christian

2015-02-01

Detailed understanding of natural fluid migration systems is essential to minimize risks during hydrocarbon exploration and to evaluate the long-term efficiency of the subsurface storage of waste water and gas from hydrocarbon production as well as CO2. The Southern Viking Graben (SVG) hosts numerous focused fluid flow structures in the shallow (expressions of vertical fluid conduits are variously known as seismic chimneys or pipes. Seismic pipes are known to form large clusters. Seismic chimneys have so far been described as solitary structures. Here, we show that the study area in the SVG hosts more than 46 large-scale vertical chimney structures, which can be divided in three categories implying different formation processes. Our analysis reveals that seal-weakening, formation-wide overpressure and the presence of free gas are required to initiate the formation of vertical fluid conduits in the SVG. The presence of numerous vertical fluid conduits implies inter-stratigraphic hydraulic connectivity, which significantly affects the migration of fluids in the subsurface. Chimney structures are important for understanding the transfer of pore pressure anomalies to the shallow parts of the basin.

3D NUMERICAL STUDY OF FLOW IN A SOLAR CHIMNEY POWER PLANT SYSTEM

Directory of Open Access Journals (Sweden)

TAHAR TAYEBI

2015-12-01

Full Text Available Heat transfer process and fluid flow in a Solar Chimney Power Plant System (SCPPS are investigated numerically. As simulation object we use the Spanish prototype plant. The calculative model and boundary conditions in calculation are introduced. Boussinesq model was chosen in the natural convection processus, Discrete Ordinate radiation model was employed for radiation. The principal factors that influence on the performance of the Solar Chimney have been analysed. The effects on the flow of the Solar Chimney which caused by solar radiation intensity have been simulated. The calculated results are compared and are approximately equivalent to the relative experimental data of the Manzanares prototype. It can be concluded that the temperature difference between the inlet and outlet of collector, as well as the air velocity in the collector of the system, is increase with the increase of solar radiation intensity and the pressure throughout system is negative value.

Optimization of a solar chimney design to enhance natural ventilation in a multi-storey office building

NARCIS (Netherlands)

Gontikaki, M.; Trcka, M.; Hensen, J.L.M.; Hoes, P.

2010-01-01

Natural ventilation of buildings can be achieved with solar-driven, buoyancy-induced airflow through a solar chimney channel. Research on solar chimneys has covered a wide range of topics, yet study of the integration in multi-storey buildings has been performed in few numerical studies, where

Abundance and distribution of fatty acids within the walls of an active deep-sea sulfide chimney

Science.gov (United States)

Li, Jiwei; Zhou, Huaiyang; Peng, Xiaotong; Fu, Meiyan; Chen, Zhiqiang; Yao, Huiqiang

2011-04-01

Abundance and distribution of total fatty acids (TFAs) were examined along the physicochemical gradient within an active hydrothermal chimney collected from the Main Endeavour segment of Juan de Fuca Ridge. Approximately 27 fatty acids are identified with a chain-length ranging from C12 to C22. From the exterior to the interior of the chimney walls, the total concentrations of TFAs (∑ TFAs) show a trend of evident decrease. The observed compositions of TFAs are rich in bacterial biomarkers especially monounsaturated fatty acids (MUFAs) and minor branched and cyclopropyl FAs. On the basis of the species-specific FAs and bacterial 16SrRNA gene analysis (Li et al., unpublished data), sulfur-based metabolism appears to be the essential metabolic process in the chimney. Furthermore, the sulfur oxidizing bacteria (SOB) are identified as a basic component of microbial communities at the exterior of the hydrothermal chimney, and its proportion shows an inward decrease while the sulfate reducing bacteria (SRB) have an inverse distribution.

Performance analysis of conventional and sloped solar chimney power plants in China

International Nuclear Information System (INIS)

Cao Fei; Zhao Liang; Li Huashan; Guo Liejin

2013-01-01

The solar chimney power plant (SCPP) has been accepted as one of the most promising approaches for future large-scale solar energy applications. This paper reports on a heat transfer model that is used to compare the performance of a conventional solar chimney power plant (CSCPP) and two sloped solar chimney power plants (SSCPPs) with the collector oriented at 30° and 60°, respectively. The power generation from SCPPs at different latitudes in China is also analyzed. Results indicate that the larger solar collector angle leads to improved performance in winter but results in lower performance in summer. It is found that the optimal collector angle to achieve the maximum power in Lanzhou, China, is around 60°. Main factors that influence the performance of SCPPs also include the system height and the air thermophysical characteristics. The ground energy loss, reflected solar radiation, and kinetic loss at the chimney outlet are the main energy losses in SCPPs. The studies also show SSCPPs are more suitable for high latitude regions in Northwest China, but CSCPPs are suggested to be built in southeastern and eastern parts of China with the combination to the local agriculture. - Highlights: ► The optimum collector angle for maximum power generation is 60° in Lanzhou. ► Main parameters influencing performances are the system height and air property. ► Ground loss, reflected loss and outlet kinetic loss are the main energy losses. ► The sloped styles are suitable for Northwest China. ► The conventional styles are suitable for Southeast and East China.

Experimental and Numerical Studies of Solar Chimney for Ventilation in Low Energy Buildings

DEFF Research Database (Denmark)

Zha, Xinyu; Zhang, Jun; Qin, Menghao

2017-01-01

As an effective way to protect environment and save energy in buildings, passive ventilation method has generated intense interest for improving indoor thermal environment in recent years. Among these passive ventilation solutions, design of solar chimney in buildings is a promising approach...... the performance of a full-scale solar chimney in a real building in East-ern China. The measured performance is compared with theoretical calculation and numerical simulation. In a solar chimney of 6.2m length, 2.8m width and 0.35m air gap, the experimental results show that air flow rate of 70.6 m3/h~1887.6 m3/h...... can be achieved during the daytime in the testing day. Comparing measured value with theoretical value, the flow rate is generally lower than the theoretical value. By data analysis, the suggested discharge coefficient Cd of solar energy in real engineering project is 0.51. With the use...

A Simple and Efficient RNA Extraction Method from Deep-Sea Hydrothermal Vent Chimney Structures.

Science.gov (United States)

Muto, Hisashi; Takaki, Yoshihiro; Hirai, Miho; Mino, Sayaka; Sawayama, Shigeki; Takai, Ken; Nakagawa, Satoshi

2017-12-27

RNA-based microbiological analyses, e.g., transcriptome and reverse transcription-quantitative PCR, require a relatively large amount of high quality RNA. RNA-based analyses on microbial communities in deep-sea hydrothermal environments often encounter methodological difficulties with RNA extraction due to the presence of unique minerals in and the low biomass of samples. In the present study, we assessed RNA extraction methods for deep-sea vent chimneys that had complex mineral compositions. Mineral-RNA adsorption experiments were conducted using mock chimney minerals and Escherichia coli total RNA solution, and showed that detectable RNA significantly decreased possibly due to adsorption onto minerals. This decrease in RNA was prevented by the addition of sodium tripolyphosphate (STPP), deoxynucleotide triphosphates (dNTPs), salmon sperm DNA, and NaOH. The addition of STPP was also effective for RNA extraction from the mixture of E. coli cells and mock chimney minerals when TRIzol reagent and the RNeasy column were used, but not when the RNeasy PowerSoil total RNA kit was used. A combination of STPP, TRIzol reagent, the RNeasy column, and sonication resulted in the highest RNA yield from a natural chimney. This indirect extraction procedure is simple, rapid, inexpensive, and may be used for large-scale RNA extraction.

Piping systems, containment pre-stressing and steel ventilation chimney

International Nuclear Information System (INIS)

Stuessi, U.

1996-01-01

Units 5 and 6 of NPP Kozloduy have been designed initially for seismic levels which are considered too low today. In the frame of an IAEA Coordinated Research Programme, a Swiss team has been commissioned by Natsionalna Elektricheska Kompania, Sofia, to analyse the relevant piping system, the containment prestressing and the steel ventilation chimney and to recommend upgrade measures for adequate seismic capacity where applicable. Seismic input had been specified by and agreed upon earlier by IAEA experts. The necessary investigations have been performed in 1995 and discussed with internationally recognized experts. The main results may be summarized as follows: Upgrades are necessary at different piping sy ports (additional snubbers or viscous dampers). These fixes can be done easily at low cost. The containment prestressing tendons are adequately designed for the specified load combinations. However, unfavourable construction features endanger the reliability. It is therefore strongly recommended to replace the tendons stepwise and to upgrade the existing monitoring system. Finally, the steel ventilation chimney may not withstand a seismic event, however the containment and diesel generator building will not be destroyed at possible impact by the chimney. On the other hand the roof of the main building has to be reinforced partially. It is recommended to continue the project for 1996 and 1997 to implement the upgrade measures mentioned above, to analyse the remaining piping systems and to consolidate all results obtained by different research groups of the IAEA programme with respect to piping systems including components and tanks

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.

Damage Identification and Seismic Vulnerability Assessment of a Historic Masonry Chimney

Directory of Open Access Journals (Sweden)

Maria-Giovanna Masciotta

2017-07-01

Full Text Available The present paper deals with the dynamic characterisation of a historical masonry chimney aimed at identifying the structural damage and assessing its seismic performance. The structure was severely damaged by a lightning accident and in-depth repair works were executed to re-instate its sound configuration. The case study is fully detailed, including the aspects of survey, inspection, diagnosis, and evolution of the dynamic properties of the system throughout the structural intervention. Considering the explicit dependence of the power spectral densities of measured nodal processes on their frequency content, a spectrum-driven algorithm is used to detect and locate the damage. The paper shows that the eigenparameters obtained from the decomposition of the response power spectrum matrix are sensitive to system’s changes caused by evolutionary damage scenarios, thereby resulting excellent indicators for assessing both the presence and position of structural vulnerabilities. The results are compared with the ones from other modal-based damage identification methods and the strengths/limitations of the tools currently available in literature are extensively discussed. Finally, based on the crack pattern surveyed before the repair works, the weakest links of the chimney are identified and the most meaningful collapse mechanisms are analysed to verify the seismic capacity of the structure. According to the results of the kinematic analysis, the chimney does withstand the maximum site peak ground acceleration.

On the Influence of Collector Size on the Solar Chimneys Performance

Directory of Open Access Journals (Sweden)

Al-Azawiey Sundus S.

2017-01-01

Full Text Available Performance of solar chimney power plant system is highly influenced by the design geometries. The collector size is logically enhances the solar chimney performance, but the trend of enhancement is not yet investigated. In the present work, experimental and numerical investigations have been carried out to ascertain, in terms of qualitative and quantitative evaluation, the effect of the collector diameter. Daily thermal efficiency has been determined at four different collector diameter. Two different collector diameters, 3.0 and 6.0 m, have been investigated experimentally, and then scaled up, to 9.0 and 12.0 m, by numerical simulation using ANSYS-FLUENT®15 software. Results demonstrated that collector diameter has effectively influenced the system performance. Larger collector diameter imposed increase in the velocity, temperature and the daily average thermal efficiency of the system. From the experimental results, increasing the collector diameter from 3.0 to 6.0 m has increased the daily average thermal efficiency of the collector from 9.81 to 12.8. Simulation results at 800 W/m2 irradiation revealed that the velocity in the chimney have increased from 1.66 m/s at 3.0 m collector diameter to 2.34, 2.47 and 2.63 m/s for 6.0, 9.0 and 12.0 m collector diameters, respectively.

Early- and Mid-term Results of the Chimney Technique in the Repair of Aortic Arch Pathologies

International Nuclear Information System (INIS)

Zou, Junjie; Jiao, Yuanyong; Zhang, Xiwei; Jiang, Jun; Yang, Hongyu; Ma, Hao

2016-01-01

PurposeTo examine the safety, feasibility, and mid-term efficacy of the chimney technique for aortic arch pathologies.MethodsFrom February 2011 to December 2014, a total of 35 patients (30 men; mean age 54.3 ± 14.1 years) with aortic arch pathologies underwent thoracic endovascular aortic repair combined with chimney stents. The indication was a proximal landing zone <1.5 cm. Follow-up was performed at 3, 6, and 12 months and then yearly thereafter.ResultsA total of 36 chimney stents were deployed (innominate artery, n = 1; left common carotid artery, n = 9; right subclavian artery, n = 1; left subclavian artery, n = 25). The technical success rate was 94.3 % (33/35). Immediate type Ia endoleaks (ELIa) were observed in two patients (8.6 %, 2/35). Twenty-five patients were successfully followed-up for a median period of 29.3 months (range, 6–48 months). One patient died due to aortic dissection aneurysm rupture at 36 months (mortality rate of 4 %, 1/25). Three late ELIa were observed and no reinterventions were performed. The overall incidence of ELIa was 20 % (5/25). During follow-up, the patency rate for chimney stents was 92 % (23/25).ConclusionOur limited experience demonstrates that the chimney technique is a viable and relatively safe treatment for patients with challenging thoracic aortic pathologies at least in the mid-term follow-up period.

Early- and Mid-term Results of the Chimney Technique in the Repair of Aortic Arch Pathologies

Energy Technology Data Exchange (ETDEWEB)

Zou, Junjie; Jiao, Yuanyong, E-mail: wishlucky@163.com, E-mail: johemail@163.com; Zhang, Xiwei; Jiang, Jun; Yang, Hongyu; Ma, Hao [First Affiliated Hospital of Nanjing Medical University, Division of Vascular Surgery, Department of General Surgery (China)

2016-11-15

PurposeTo examine the safety, feasibility, and mid-term efficacy of the chimney technique for aortic arch pathologies.MethodsFrom February 2011 to December 2014, a total of 35 patients (30 men; mean age 54.3 ± 14.1 years) with aortic arch pathologies underwent thoracic endovascular aortic repair combined with chimney stents. The indication was a proximal landing zone <1.5 cm. Follow-up was performed at 3, 6, and 12 months and then yearly thereafter.ResultsA total of 36 chimney stents were deployed (innominate artery, n = 1; left common carotid artery, n = 9; right subclavian artery, n = 1; left subclavian artery, n = 25). The technical success rate was 94.3 % (33/35). Immediate type Ia endoleaks (ELIa) were observed in two patients (8.6 %, 2/35). Twenty-five patients were successfully followed-up for a median period of 29.3 months (range, 6–48 months). One patient died due to aortic dissection aneurysm rupture at 36 months (mortality rate of 4 %, 1/25). Three late ELIa were observed and no reinterventions were performed. The overall incidence of ELIa was 20 % (5/25). During follow-up, the patency rate for chimney stents was 92 % (23/25).ConclusionOur limited experience demonstrates that the chimney technique is a viable and relatively safe treatment for patients with challenging thoracic aortic pathologies at least in the mid-term follow-up period.

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.

Modeling and optimization of a novel solar chimney cogeneration power plant combined with solid oxide electrolysis/fuel cell

International Nuclear Information System (INIS)

Joneydi Shariatzadeh, O.; Refahi, A.H.; Abolhassani, S.S.; Rahmani, M.

2015-01-01

Highlights: • Proposed a solar chimney cogeneration power plant combined with solid oxide fuel cell. • Conducted single-objective economic optimization of cycle by genetic algorithm. • Stored surplus hydrogen in season solarium to supply electricity in winter by SOFC. - Abstract: Using solar chimney in desert areas like El Paso city in Texas, USA, with high intensity solar radiation is efficient and environmental friendly. However, one of the main challenges in terms of using solar chimneys is poor electricity generation at night. In this paper, a new power plant plan is proposed which simultaneously generates heat and electricity using a solar chimney with solid oxide fuel cells and solid oxide electrolysis cells. In one hand, the solar chimney generates electricity by sunlight and supplies a part of demand. Then, additional electricity is generated through the high temperature electrolysis which produces hydrogen that is stored in tanks and converted into electricity by solid oxide fuel cells. After designing and modeling the cycle components, the economic aspect of this power plant is considered numerically by means of genetic algorithm. The results indicate that, 0.28 kg/s hydrogen is produced at the peak of the radiation. With such a hydrogen production rate, this system supplies 79.26% and 37.04% of the demand in summer and winter respectively in a district of El Paso city.

Comparison of the Energy Conversion Efficiency of a Solar Chimney and a Solar PV-Powered Fan for Ventilation Applications

Directory of Open Access Journals (Sweden)

Lubomír Klimeš

2018-04-01

Full Text Available A study into the performance of a solar chimney and a solar photovoltaic (PV-powered fan for ventilation applications was carried out using numerical simulations. The performance of the solar chimney was compared with that of a direct current (DC fan powered by a solar PV panel. The comparison was carried out using the same area of the irradiated surface—the area of the solar absorber plate in the case of the solar chimney and the area of the solar panel in the case of the photovoltaic-powered fan. The two studied cases were compared under various solar radiation intensities of incident solar radiation. The results indicate that the PV-powered fans significantly outperform solar chimneys in terms of converting solar energy into the kinetic energy of air motion. Moreover, ventilation with PV-powered fans offers more flexibility in the arrangement of the ventilation system and also better control of the air flow rates in the case of battery storage.

Positional Arrangements of Waste Exhaust Gas Ducts of C-Type Balanced Chimney Heating Devices on Building Façades

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Erkan AVLAR

2009-01-01

Full Text Available In Turkey today, with the increase in availability of natural gas,detached heating devices are being preferred over existingheating devices. Due to the lack of chimneys in existing buildingsin Turkey or the presence of chimneys that fail to conformto standards, the use of C-type balanced chimney devices has increased.C-type balanced chimney devices take the combustionair directly from the outside by a specific air duct as detachedheating equipment, with enclosed combustion chambers anda specific waste gas exhaust duct, and they are ventilated independentlyof the field of equipment. Because of their essentiality,the use of a chimney is not required in these devices;the waste gas is exhausted through walls, windows, doors, orbalconies. The natural gas is a clean fossil fuel that requires nostorage in buildings and is easy to use. However, water vapor,carbon dioxide and nitrogen oxides are produced by the combustionof natural gas. It is widely known that high concentrationsof these products can have some adverse effects onhumans such as dizziness, headaches and nausea. As a result,the waste products could recoil through wall openings on thefaçade to create unhealthy indoor environments that could bedangerous to human health. Therefore, the importance of standardsand regulations about the positional arrangements of thewaste gas exhaust ducts of C-type balanced chimney devices onbuilding façades is increasing. In this research, we analyze thestudies of the Institution of Turkish Standards, Chamber of MechanicalEngineers, gas distribution companies, municipalitiesand authorized firms and compare the criteria to determine thenecessary application method. According to our comparison ofthe references accessed, the criteria are not uniform.

A study of the various baffles used in the Marcoule chimneys and the search for a new model (1961)

International Nuclear Information System (INIS)

Chassany, J.; Salaun-Penquer, G.

1961-01-01

The baffle placed at the top of a chimney determines the shape of the smoke pall for low exit-velocities. The G. 1 type baffle was studied taking into account the characteristics of its collar: totally hollow - partially hollow - solid; on a ribbed chimney or on a plain chimney. The Pu type baffle was also tested. The search for a new type of baffle was limited to variants of the blade - type baffle: - a porous envelope device; - a cone - shaped device and - a deflector of the cupel type. Only the blade-type baffle was rejected, efficient solutions are proposed using the other types or their combinations. (authors) [fr

Low-Field Bi-Skyrmion Formation in a Noncentrosymmetric Chimney Ladder Ferromagnet

Science.gov (United States)

Takagi, R.; Yu, X. Z.; White, J. S.; Shibata, K.; Kaneko, Y.; Tatara, G.; Rønnow, H. M.; Tokura, Y.; Seki, S.

2018-01-01

The real-space spin texture and the relevant magnetic parameters were investigated for an easy-axis noncentrosymmetric ferromagnet Cr11 Ge19 with Nowotny chimney ladder structure. Using Lorentz transmission electron microscopy, we report the formation of bi-Skyrmions, i.e., pairs of spin vortices with opposite magnetic helicities. The quantitative evaluation of the magnetocrystalline anisotropy and Dzyaloshinskii-Moriya interaction (DMI) proves that the magnetic dipolar interaction plays a more important role than the DMI on the observed bi-Skyrmion formation. Notably, the critical magnetic field value required for the formation of bi-Skyrmions turned out to be extremely small in this system, which is ascribed to strong easy-axis anisotropy associated with the characteristic helix crystal structure. The family of Nowotny chimney ladder compounds may offer a unique material platform where two distinctive Skyrmion formation mechanisms favoring different topological spin textures can become simultaneously active.

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.

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

International Nuclear Information System (INIS)

Cao, Fei; Li, Huashan; Ma, Qiuming; Zhao, Liang

2014-01-01

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

Polar orientation of renal grafts within the proximal seal zone affects risk of early type IA endoleaks after chimney endovascular aneurysm repair.

Science.gov (United States)

Tran, Kenneth; Ullery, Brant W; Itoga, Nathan; Lee, Jason T

2018-04-01

The objective of this study was to describe the polar orientation of renal chimney grafts within the proximal seal zone and to determine whether graft orientation is associated with early type IA endoleak or renal graft compression after chimney endovascular aneurysm repair (ch-EVAR). Patients who underwent ch-EVAR with at least one renal chimney graft from 2009 to 2015 were included in this analysis. Centerline three-dimensional reconstructions were used to analyze postoperative computed tomography scans. The 12-o'clock polar position was set at the takeoff of the superior mesenteric artery. Relative polar positions of chimney grafts were recorded at the level of the renal artery ostium, at the mid-seal zone, and at the proximal edge of the graft fabric. Early type IA endoleaks were defined as evidence of a perigraft flow channel within the proximal seal zone. There were 62 consecutive patients who underwent ch-EVAR (35 double renal, 27 single renal) for juxtarenal abdominal aortic aneurysms with a mean follow-up of 31.2 months; 18 (29%) early type IA "gutter" endoleaks were identified. During follow-up, the majority of these (n = 13; 72%) resolved without intervention, whereas two patients required reintervention (3.3%). Estimated renal graft patency was 88.9% at 60 months. Left renal chimney grafts were most commonly at the 3-o'clock position (51.1%) at the ostium, traversing posteriorly to the 5- to 7-o'clock positions (55.5%) at the fabric edge. Right renal chimney grafts started most commonly at the 9-o'clock position (n = 17; 33.3%) and tended to traverse both anteriorly (11 to 1 o'clock; 39.2%) and posteriorly (5 to 7 o'clock; 29.4%) at the fabric edge. In the polar plane, the majority of renal chimney grafts (n = 83; 85.6%) traversed 90 degrees were independently associated with early type IA endoleaks (odds ratio, 11.5; 95% confidence interval, 2.1-64.8) even after controlling for other device and anatomic variables. Polar orientation of the chimney

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

International Nuclear Information System (INIS)

Chen, Kai; Wang, Jiangfeng; Dai, Yiping; Liu, Yuqi

2014-01-01

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

Using exhaled carbon monoxide and carboxyhemoglobin to evaluate the effectiveness of a chimney stove model in Peru.

Science.gov (United States)

Eppler, Adam R; Fitzgerald, Christopher; Dorner, Stephen C; Aguilar-Villalobos, Manuel; Rathbun, Stephen L; Adetona, Olorunfemi; Naeher, Luke P

2013-01-01

Measurement of biological indicators of physiological change may be useful in evaluating the effectiveness of stove models, which are intended to reduce indoor smoke exposure and potential health effects. We examined changes in exhaled carbon monoxide (CO), percentage carboxy-hemoglobin, and total hemoglobin in response to the installation of a chimney stove model by the Juntos National Program in Huayatan, Peru in 2008. Biomarkers were measured in a convenience sample comprising 35 women who met requirements for participation, and were measured before and three weeks after installation of a chimney stove. The relationships between exposure to indoor smoke and biomarker measurements were also analyzed using simple linear regression models. Exhaled CO reduced from 6.71 ppm (95% CI 5.84-7.71) to 3.14 ppm (95% CI 2.77-3.66) three weeks after stove installation (P < 0.001) while % COHb reduced from 1.76% (95% CI 1.62-1.91) to 1.18% (95% CI 1.12-1.25; P < 0.001). Changes in exhaled CO and % COHb from pre- to post-chimney stove installation were not correlated with corresponding changes in exposure to CO and PM2.5 even though the exposures also reduced after stove installation. Exhaled CO and % COHb both showed improvement with reduction in concentration after the installation of the chimney cook stoves, indicating a positive physiological response subsequent to the intervention.

Solar chimney for natural ventilation: A review

Science.gov (United States)

Dhrubo, Abir Ahsan; Alam, Chowdhury Sadid; Rahman, Md. Mustafizur; Islam, A. K. M. Sadrul

2017-06-01

In the 21st century the talk of the time has been proper use of renewable energy sources due to the continuous depletion of non-renewable energy sources and global warming as a result of combustion of fossil fuels. The energy situation in the 3rd world countries is even worse. The continuous industrial development in the 1st world countries is hugely responsible for global temperature increase and greenhouse gas (GHG) emissions which badly affect the countries like Bangladesh. As of April 2016, the electricity generation capacity of Bangladesh was 12,399 MW to which only 60% of the total population have access to. The shortage of electricity during the summer season makes life very difficult. Cooling of buildings requires a large quantity of energy in the summer. An alternative cooling system can reduce the dependency on electricity. This paper specially deals with a passive cooling system that reduces pressure on the electricity supply and focuses on renewable energy sources. Here a different process engineering has been discussed which incorporates Earth-to-Air Heat Exchangers with solar collector enhanced solar chimney system. In this study natural ventilation of buildings, using solar chimney system is reviewed extensively. Experimentally it has already been observed that sufficient temperature drop takes place 2-3 m within the undisturbed ground, which can work as a heat sink for ambient air if passed through and can lead to attaining comfort zone at a confined location. During peak hours of summer this kind of system may work as a very efficient cooling system and reduces extra load on electricity supply.

Solar chimney integrated with passive evaporative cooler applied on glazing surfaces

International Nuclear Information System (INIS)

Al Touma, Albert; Ghali, Kamel; Ghaddar, Nesreen; Ismail, Nagham

2016-01-01

This study investigates the performance of a hybrid system applied on glazing surfaces for reducing the space cooling load and radiation asymmetry. The proposed system combines the principles of passive evaporative cooling with the natural buoyant flow in solar chimneys to entrain outdoor air and attenuate the window surface temperature. A predictive heat and mass transport model combining the evaporative cooler, glazing section, solar chimney and an office space is developed to study the system performance in harshly hot climates. The developed model was validated through experiments conducted in a twin climatic chamber for given ambient temperature, humidity, and solar radiation conditions. Good agreement was found between the measured and the predicted window temperatures and space loads at maximum discrepancy lower than 4.3%. The proposed system is applied to a typical office space to analyze its effectiveness in reducing the window temperature, the space load and radiation asymmetry, while maintaining the indoor comfort conditions. Results have shown that the system is reduced the space load by −19.8% and attenuated the radiation asymmetry significantly for office spaces having window-to-wall ratio of 40% in climate of Riyadh, KSA. The system performance diminished when applied in locations suffering from humid weather climates. - Highlights: • A passive evaporative-cooled solar chimney system is introduced to decrease window temperature. • A mathematical model is developed of the system to predict induce air flow and window surface temperature. • The model is validated with experiments in twin room climatic chamber and using artificial solar lamps. • The system reduces window maximum temperature by 5 °C in the hot dry climate of Riyadh, KSA. • It reduced the space load by 19.4% for office spaces at window-to-wall ratio of 40% in Riyadh, KSA.

Solar chimney for the natural ventilation of buildings: simulation and mediation; Chimenea solar para la ventilacion natural de edificios: simulacion y mediacion

Energy Technology Data Exchange (ETDEWEB)

Lanceta, D.; Llorente, J.

2008-07-01

In this article, the first part of a research project about the modelling of a solar chimney is presented. In this first part, the average ventilation flows measured in an experimental installation have been compared to the results obtained by CFD (Computational Fluid Dynamics) simulations. In order to do so, a solar chimney with a cross-section of 0.78 m x 0.156 m, height 3,6 m, has been constructed. The chimney consists of a glass surface oriented towards the south. The internal (absorber) surface is made of a copper plate, which has been painted black in order to increase the solar absorption. The chimney is connected to a room measuring 5 m x 2.5 m x 2.5 m, from where it extracts air. The comparison of the results obtained by measurements with those obtained by CFD simulations show that computational tools are accurate enough to predict the behaviour of natural buoyancy in this kind of installations. (Author)

DESIGN AND CONSTRUCTION OF A PROTOTYPE SOLAR UPDRAFT CHIMNEY IN ASWAN/EGYPT

Directory of Open Access Journals (Sweden)

Reinhard Harte

2017-06-01

Full Text Available This work is part of a joint project funded by the Science and Technology Development Fund (STDF of the Arab republic of Egypt and the Federal Ministry of Education and Research (BMBF of the Federal Republic of Germany. Continuation of the use of fossil fuels in electricity production systems causes many problems such as: global warming, other environmental concerns, the depletion of fossil fuels reserves and continuing rise in the price of fuels. One of the most promising paths to solve the energy crisis is utilizing the renewable energy resources. In Egypt, high insolation and more than 90 percent available desert lands are two main factors that encourage the full development of solar power plants for thermal and electrical energy production. With an average temperature of about 40 °C for more than half of the year and average annual sunshine of about 3200 hours, which is close to the theoretical maximum annual sunshine hours, Aswan is one of the hottest and sunniest cities in the world. This climatic condition makes the city an ideal place for implementing solar energy harvesting projects from solar updraft tower. Therefore, a Solar Chimney Power Plant (SCPP is being installed at Aswan City. The chimney height is 20.0 m, its diameter is 1.0m and the collector is a four-sided pyramid, which has a side length of 28.5 m. A mathematical model is used to predict its performance. The model shows that the plant can produce a maximum theoretical power of 2 kW. Moreover, a CFD code is used to analyse the temperature and velocity distribution inside the collector, turbine and chimney at different operating conditions. Static calculations, including dead weight and wind forces on the solar updraft chimney and its solar collector, have been performed for the prototype. Mechanical loading and ambient impact on highly used industrial structures such as chimneys and masts cause lifetime-related deteriorations. Structural degradations occur not only from

Seafloor geological studies of active gas chimneys offshore Egypt (central Nile Fan).

NARCIS (Netherlands)

Dupre, S.; Woodside, J.M.; Foucher, J.-P.; de Lange, G.; Mascle, J.; Boetius, A.; Mastalerz, V.; Stadnitskaia, A.; Ondreas, H.; Huguen, C.; Harmegnies, F.; Gontharet, S.; Loncke, L; Deville, E.; Niemann, H.; Omoregie, E.; Olu-Le Roy, K; Fiala-Medioni, A.; Dahlmann, A.; Caprais, J.-C.; Prinzhofer, A.; Sibuet, M.; Pierre, C.

2007-01-01

Four mud volcanoes of several kilometres diameter named Amon, Osiris, Isis, and North Alex and located above gas chimneys on the Central Nile Deep Sea Fan, were investigated for the first time with the submersible Nautile. One of the objectives was to characterize the seafloor morphology and the

S- and Sr-isotopic compositions in barite-silica chimney from the Franklin Seamount, Woodlark Basin, Papua New Guinea: constraints on genesis and temporal variability of hydrothermal fluid

Science.gov (United States)

Ray, Durbar; Banerjee, Ranadip; Balakrishnan, S.; Paropkari, Anil L.; Mukhopadhyay, Subir

2017-07-01

Isotopic ratios of strontium and sulfur in six layers across a horizontal section of a hydrothermal barite-silica chimney from Franklin Seamount of western Woodlark Basin have been investigated. Sr-isotopic ratios in barite samples (87Sr/86Sr = 0.70478-0.70493) are less radiogenic than seawater (87Sr/86Sr = 0.70917) indicating that substantial leaching of sub-seafloor magma was involved in the genesis of hydrothermal fluid. The SO2 of magma likely contributed a considerable amount of lighter S-isotope in fluid and responsible for the formation of barite, which is isotopically lighter (δ34S = 19.4-20.5 ‰) than modern seawater (δ34S 21 ‰). The systematic changes in isotopic compositions across the chimney wall suggest temporal changes in the mode of mineral formation during the growth of the chimney. Enrichment of heavy S- and Sr-isotopes (δ34S = 20.58 ‰; 87Sr/86Sr = 0.70493) in the outermost periphery of the chimney indicates that, at the initial stage of chimney development, there was a significant contribution of seawater sulfate during barite mineralization. Thereafter, thickening of chimney wall occurred due to precipitation of fluid carrying more magmatic components relative to seawater. This led to a gradual enrichment of lighter isotopes (δ34S = 20.42-19.48 ‰; 87Sr/86Sr = 0.70491-0.704787) toward the inner portion of the chimney wall. In contrast, the innermost layer surrounding the fluid conduit is characterized by heavier and more radiogenic isotopes (δ34S = 20.3 ‰; 87Sr/86Sr = 0.7049). This suggests there was increasing influence of percolating seawater on the mineral paragenesis at the waning phase of the chimney development.

Microbial Diversity of Carbonate Chimneys at the Lost City Hydrothermal Field: Implications for Life-Sustaining Systems in Peridotite Seafloor Environments

Science.gov (United States)

Schrenk, M. O.; Cimino, P.; Kelley, D. S.; Baross, J. A.

2002-12-01

The Lost City Hydrothermal Field (LCHF) is a novel peridotite-hosted vent environment discovered in Dec. 2000 at 30 N near the Mid-Atlantic Ridge. This field contains multiple large (up to 60 m), carbonate chimneys venting high pH (9-10), moderate temperature (45-75 C) fluids. The LCHF is unusual in that it is located on 1.5 my-old oceanic crust, 15 km from the nearest spreading axis. Hydrothermal flow in this system is believed to be driven by exothermic serpentinization reactions involving iron-bearing minerals in the underlying seafloor. The conditions created by such reactions, which include significant quantities of dissolved methane and hydrogen, create habitats for microbial communities specifically adapted to this unusual vent environment. Ultramafic, reducing hydrothermal environments like the LCHF may be analogous to geologic settings present on the early Earth, which have been suggested to be important for the emergence of life. Additionally, the existence of hydrothermal environments far away from an active spreading center expands the range of potential life-supporting environments elsewhere in the solar system. To study the abundance and diversity of microbial communities inhabiting the environments that characterize the LCHF, carbonate chimney samples were analyzed by microscopic and molecular methods. Cell densities of between 105 and 107 cells/g were observed within various samples collected from the chimneys. Interestingly, 4-11% of the microbial population in direct contact with vent fluids fluoresced with Flavin-420, a key coenzyme involved in methanogenesis. Enrichment culturing from chimney material under aerobic and anaerobic conditions yielded microorganisms in the thermophilic and mesophilic temperature regimes in media designed for methanogenesis, methane-oxidation, and heterotrophy. PCR analysis of chimney material indicated the presence of both Archaea and Eubacteria in the carbonate samples. SSU rDNA clone libraries constructed from the

The role of leak air in a double-wall chimney

Science.gov (United States)

Lichtenegger, Klaus; Hebenstreit, Babette; Pointner, Christian; Schmidl, Christoph; Höftberger, Ernst

2015-06-01

In modern buildings with tight shells, often room-independent air supply is required for proper operation of biomass stoves. One possibility to arrange this supply is to use a double-wall chimney with flue gas leaving through the pipe and fresh air entering through the annular gap. A one-dimensional quasi-static model based on balance equations has been developed and compared with experimental data. Inclusion of leak air is crucial for reproduction of the experimental results.

A Comparative Study of CFD Models of a Real Wind Turbine in Solar Chimney Power Plants

Directory of Open Access Journals (Sweden)

Ehsan Gholamalizadeh

2017-10-01

Full Text Available A solar chimney power plant consists of four main parts, a solar collector, a chimney, an energy storage layer, and a wind turbine. So far, several investigations on the performance of the solar chimney power plant have been conducted. Among them, different approaches have been applied to model the turbine inside the system. In particular, a real wind turbine coupled to the system was simulated using computational fluid dynamics (CFD in three investigations. Gholamalizadeh et al. simulated a wind turbine with the same blade profile as the Manzanares SCPP’s turbine (FX W-151-A blade profile, while a CLARK Y blade profile was modelled by Guo et al. and Ming et al. In this study, simulations of the Manzanares prototype were carried out using the CFD model developed by Gholamalizadeh et al. Then, results obtained by modelling different turbine blade profiles at different turbine rotational speeds were compared. The results showed that a turbine with the CLARK Y blade profile significantly overestimates the value of the pressure drop across the Manzanares prototype turbine as compared to the FX W-151-A blade profile. In addition, modelling of both blade profiles led to very similar trends in changes in turbine efficiency and power output with respect to rotational speed.

Retrograde Ascending Dissection After Thoracic Endovascular Aortic Repair Combined With the Chimney Technique and Successful Open Repair Using the Frozen Elephant Trunk Technique.

Science.gov (United States)

Hirano, Koji; Tokui, Toshiya; Nakamura, Bun; Inoue, Ryosai; Inagaki, Masahiro; Maze, Yasumi; Kato, Noriyuki

2018-01-01

The chimney technique can be combined with thoracic endovascular aortic repair (TEVAR) to both obtain an appropriate landing zone and maintain blood flow of the arch vessels. However, surgical repair becomes more complicated if retrograde type A aortic dissection occurs after TEVAR with the chimney technique. We herein report a case involving a 73-year-old woman who developed a retrograde ascending dissection 3 months after TEVAR for acute type B aortic dissection. To ensure an adequate proximal sealing distance, the proximal edge of the stent graft was located at the zone 2 level and an additional bare stent was placed at the left subclavian artery (the chimney technique) at the time of TEVAR. Enhanced computed tomography revealed an aortic dissection involving the ascending aorta and aortic arch. Surgical aortic repair using the frozen elephant trunk technique was urgently performed. The patient survived without stroke, paraplegia, renal failure, or other major complications. Retrograde ascending dissection can occur after TEVAR combined with the chimney technique. The frozen elephant trunk technique is useful for surgical repair in such complicated cases.

Use of Suture-Mediated Closure Device in Percutaneous Direct Carotid Puncture During Chimney-Thoracic Endovascular Aortic Repair

International Nuclear Information System (INIS)

Chan, Gabriel; Quek, Lawrence Hwee Han; Tan, Glenn Leong Wei; Pua, Uei

2016-01-01

BackgroundInsertion of a carotid chimney graft during thoracic endovascular aortic repair (Ch-TEVAR) is a recognized technique to extend the proximal landing zone into the aortic arch in the treatment of thoracic aortic disease. Conventional technique requires surgical exposure of the carotid artery for insertion of the carotid chimney graft.MethodologyWe describe our experience in the use of a suture-mediated closure device in percutaneous Ch-TEVAR in four patients.ResultsSuccessful hemostasis was achieved in all four patients. No complications related to the carotid puncture were recorded.ConclusionWe conclude that using suture-mediated closure device for carotid closure appears feasible and deserves further studies as a potential alternative to conventional surgical approach.

Use of Suture-Mediated Closure Device in Percutaneous Direct Carotid Puncture During Chimney-Thoracic Endovascular Aortic Repair

Energy Technology Data Exchange (ETDEWEB)

Chan, Gabriel, E-mail: dr.changabriel@gmail.com; Quek, Lawrence Hwee Han, E-mail: lawrence-quek@ttsh.com.sg [Tan Tock Seng Hospital, Department of Diagnostic Radiology (Singapore); Tan, Glenn Leong Wei, E-mail: glenn-tan@ttsh.com.sg [Tan Tock Seng Hospital, Department of General Surgery (Singapore); Pua, Uei, E-mail: druei@yahoo.com [Tan Tock Seng Hospital, Department of Diagnostic Radiology (Singapore)

2016-07-15

BackgroundInsertion of a carotid chimney graft during thoracic endovascular aortic repair (Ch-TEVAR) is a recognized technique to extend the proximal landing zone into the aortic arch in the treatment of thoracic aortic disease. Conventional technique requires surgical exposure of the carotid artery for insertion of the carotid chimney graft.MethodologyWe describe our experience in the use of a suture-mediated closure device in percutaneous Ch-TEVAR in four patients.ResultsSuccessful hemostasis was achieved in all four patients. No complications related to the carotid puncture were recorded.ConclusionWe conclude that using suture-mediated closure device for carotid closure appears feasible and deserves further studies as a potential alternative to conventional surgical approach.

Solar chimney power generation project - The case for Botswana

International Nuclear Information System (INIS)

Ketlogetswe, Clever; Seabe, Omphemetse O.; Fiszdon, Jerzy K.

2008-01-01

Import of a huge proportion of electrical energy from the Southern African Power Pool, and the geographical location and population distribution of Botswana stimulated the need to consider renewable energy as an alternative to imported power. The paper describes a systematic experimental study on a mini-solar chimney system. Particular attention is given to measurements of air velocity, temperature and solar radiation. The results for the selected 5 and 6 clear days of October and November, respectively, are presented. These results enable the relationship between average insolation, temperature difference and velocity for selected clear days to be discussed. (author)

The use of a rubble chimney for denitrification of irrigation return waters

Energy Technology Data Exchange (ETDEWEB)

Evans, Roy B; Kruger, Paul [Civil Engineering Department, Stanford University (United States)

1970-05-15

Biological denitrification has been proposed as a means of removing nitrates from waste waters to control eutrophication in receiving waters. A potential use for this method is the treatment of irrigation return waters containing high concentrations of nitrate-nitrogen, since direct discharge of such wastes may cause objectionable algal growth in the receiving waters. For example, the process may be used to treat agricultural waste waters in the San Joaquin Valley in California, where an estimated 580,000 acre-feet/year of return waters, containing 20 mg/l of nitrate-nitrogen, will require disposal by A.D. 2020. Two methods of biological denitrification are presently under study for possible use in the San Joaquin Valley. In one method nitrates are reduced to nitrogen gas by bacterial action in deep ponds; in the other method bacterial denitrification takes place in biological filters. In biological filters, bacteria are grown on columns of submerged stones. A possible alternative to the conventional construction of these filters is the creation of a rubble chimney by a contained nuclear explosion. This paper presents the results of a preliminary investigation of the feasibility of using a rubble chimney as a biological filter for denitrification. (author)

The use of a rubble chimney for denitrification of irrigation return waters

International Nuclear Information System (INIS)

Evans, Roy B.; Kruger, Paul

1970-01-01

Biological denitrification has been proposed as a means of removing nitrates from waste waters to control eutrophication in receiving waters. A potential use for this method is the treatment of irrigation return waters containing high concentrations of nitrate-nitrogen, since direct discharge of such wastes may cause objectionable algal growth in the receiving waters. For example, the process may be used to treat agricultural waste waters in the San Joaquin Valley in California, where an estimated 580,000 acre-feet/year of return waters, containing 20 mg/l of nitrate-nitrogen, will require disposal by A.D. 2020. Two methods of biological denitrification are presently under study for possible use in the San Joaquin Valley. In one method nitrates are reduced to nitrogen gas by bacterial action in deep ponds; in the other method bacterial denitrification takes place in biological filters. In biological filters, bacteria are grown on columns of submerged stones. A possible alternative to the conventional construction of these filters is the creation of a rubble chimney by a contained nuclear explosion. This paper presents the results of a preliminary investigation of the feasibility of using a rubble chimney as a biological filter for denitrification. (author)

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.

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.

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

Geomicrobiological exploration and characterization of novel deep-sea hydrothermal activities accompanying with extremely acidic white smokers and elemental sulfur chimneys at the TOTO caldera in the Mariana Volcanic Arc

Science.gov (United States)

Takai, K.; Nakagawa, T.; Suzuki, Y.; Hirayama, H.; Kosaka, A.; Tsunogai, U.; Gamo, T.; Nealson, K. H.; Horikoshi, K.

2004-12-01

Novel hydrothermal activities accompanying effluent white smokers and elemental sulfur chimney structures at the northeast lava dome of the TOTO caldera depression in the Mariana Volcanic Arc were explored by the manned submersible Shinkai 6500 and characterized by geochemical and microbiological surveys. The white smoker hydrothermal fluids were observed in the potential hydrothermal activity center of the field and represented a maximal temperature of 172 degree C and a lowest pH of 1.59, that was the lowest pH of the hydrothermal fluid ever recorded. The chimney structures consisting all of elemental sulfur (sulfur chimney) were also peculiar to the TOTO caldera hydrothermal field in the world. The geochemical characterization strongly suggested that the TOTO caldera hydrothermal field was a novel system driven by subseafloor mixing between the oxygenated seawater and the superheated volcanic gasses. Microbial community structures in a sulfur chimney structure and its formation hydrothermal fluid with a high concentration of hydrogen sulfide (15 mM) were investigated by culture-dependent and _|independent analyses. Ribosomal rRNA gene clone analysis and fluorescence in situ hybridization (FISH) analysis revealed that epsilon-Proteobacteria, specifically classified into Group G and Group B, dominated the microbial communities in the sulfur chimney structure and formed a dense microbial mat covering the sulfur chimney surface. Archaeal phylotypes were consistently minor components in the communities and related to the genera Thermococcus, Pyrodictium, Aeropyrum, and the uncultivated archaeal group of Deep-sea Hydrothermal Vent Euryarchaeotal Group. Cultivation analysis suggested that the microbial components inhabiting in the sulfur chimney structure might be entrained by hydrothermal fluids from the potential subsurface habitats

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.

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.

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

A new economic feasibility approach for solar chimney power plant design

International Nuclear Information System (INIS)

Okoye, Chiemeka Onyeka; Solyalı, Oğuz; Taylan, Onur

2016-01-01

Highlights: • A two-stage economic feasibility approach is proposed for the SCPP design. • The optimal size of the SCPP is determined by solving a nonlinear optimization model. • Energy demand and stochasticity of solar radiation and temperature are considered. • The proposed approach is evaluated on locations in Nigeria. • The proposed approach is an effective decision-making tool for the SCPP design. - Abstract: Solar chimney power plants have been accepted as one of the promising technologies for solar energy utilization. The objective of this study is to propose an effective approach to simultaneously determine the optimal dimensions of the solar chimney power plant and the economic feasibility of the proposed plant. For this purpose, a two-stage economic feasibility approach is proposed based on a new nonlinear programming model. In the first stage, the proposed optimization model which determines the optimal plant dimensions that not only minimize the discounted total cost of the system, but also satisfy the energy demand within a specified reliability taking into account the stochasticity of solar radiation and ambient temperature is solved using a commercial optimization solver that guarantees finding the global optimum. In the second stage, the net present value of building the plant is computed by deducting the discounted total cost found in the first stage from the present value of revenues obtained due to selling the electricity generated by the plant. The proposed approach is novel because it determines the optimal dimensions of the plant together with its economic feasibility by taking into account the energy demand and uncertainty in solar radiation and ambient temperature. The proposed approach is applied on a study in Potiskum, Nigeria, which reveals that building a plant with a collector diameter of 1128 m and chimney height of 715 m to Potiskum would be profitable for investors at an annual rate of return of 3% and would provide

Rio Blanco: nuclear operations and chimney reentry

International Nuclear Information System (INIS)

Woodruff, W.R.; Guido, R.S.

1975-01-01

Rio Blanco was the third experiment in the U.S. Atomic Energy Commission's Plowshare Program to develop technology to stimulate gas production from geologic formations not conducive to production by conventional means. The project was sponsored by CER Geonuclear Corporation, with the Lawrence Livermore Laboratory providing the explosives and several technical programs, such as spall measurement. Three nuclear explosives specifically designed for this application were detonated simultaneously in a minimum-diameter emplacement well using many commercially available but established-reliability components. The explosive system performed properly under extreme temperature and pressure conditions. Emplacement and stemming operations were designed with the aim of simplifying both the emplacement and reentry and fully containing the detonation products. An integrated command and control system was used with communication to all three explosives through a single coaxial cable. Reentry and the initial production testing are completed. To date 98 million standard ft 3 of chimney gas have been produced. (auth)

Thoracic aortic stent-graft placement combined with left subclavian artery 'chimney operation': therapeutic analysis of 15 cases with insufficient proximal anchor area

International Nuclear Information System (INIS)

Liu Jiayi; Huang Lianjun; Fan Zhanming; Zhang Zhaoqi

2012-01-01

Objective: To discuss the strategies for the management of insufficient proximal anchoring area during the performance of transluminal stent-graft placement (TSGP), and to evaluate the feasibility of intentional coverage of the left subclavian artery (LSA) together with left subclavian artery stent-graft placement by using 'chimney operation' technique. Methods: A total of 15 patients with thoracic aortic diseases complicated by insufficient proximal anchoring area, who were encountered in authors' hospital during the period from Dec. 2009 to April 2011, were enrolled in this study. The clinical data were retrospectively analyzed. The thoracic aortic diseases included aortic dissection (n=6), aortic pseudoaneurysm (n=1), aortic aneurysm (n=4) and penetrating ulcer (n=4). Of the 15 patients, the distance between the lesion and LSA anchoring site 15 mm in 2. TSGP was carried out. The ostium of LSA was intentionally and completely covered by thoracic aortic stent-graft and left subclavian artery stent-graft placement was subsequently performed. The patients were kept under observation for symptoms of cerebral and upper limb ischemia. The postoperative complications such as endoleak and the patency of LSA were assessed with angiography. Results: Thoracic aortic stent-graft placement was successfully carried out in all 15 patients. In addition, one 'chimney' stent was properly implanted in LSA in each patient. After the procedure, no complications of nervous system or severe ischemia of upper extremity occurred. Follow-up examinations performed between 5 days to 3 months after the treatment revealed that the aortic stent-graft remained in stable condition and no type Ⅰ endoleak occurred, meanwhile the blood flow in 'chimney' stent was unobstructed. Conclusion: Intentional LSA coverage with 'chimney operation' can expand the applicability of TSGP with high tolerability. It is especially useful for patients with left vertebral artery blood supply dominance or with

A Solar Chimney for renewable energy production: thermo-fluid dynamic optimization by CFD analyses

Science.gov (United States)

Montelpare, S.; D'Alessandro, V.; Zoppi, A.; Costanzo, E.

2017-11-01

This paper analyzes the performance of a solar tower designed for renewable energy production. The Solar Chimney Power Plant (SCPP) involves technology that converts solar energy by means of three basic components: a large circular solar collector, a high tower in the center of the collector and a turbine generator inside the chimney. SCPPs are characterized by long term operational life, low maintenance costs, zero use of fuels, no use of water and no emissions of greenhouse gases. The main problem of this technology is the low energy global conversion coefficient due to the presence of four conversions: solar radiation > thermal energy > kinetic energy > mechanical energy > electric energy. This paper defines its starting point from the well known power plant of Manzanares in order to calibrate a numerical model based on finite volumes. Following that, a solar tower with reduced dimensions was designed and an analysis on various geometric parameters was conducted: on the inlet section, on the collector slope, and on the fillet radius among the SUPP sections. Once the optimal solution was identified, a curved deflectors able to induce a flow swirl along the vertical tower axis was designed.

Mineralogy and Geochemistry from Trollveggen Vent Field Chimneys and Metalliferous Sediments (Mohns Ridge, West Jan Mayen Fracture Zone at 71°N)

Science.gov (United States)

Dias, S.; Cruz, I.; Fonseca, R.; Barriga, F. J.; Pedersen, R.

2010-12-01

The Jan Mayen vent fields were discovered in the Mohns Ridge during an expedition with the Norwegian research vessel "G.O. Sars" in July 2005. They comprise two main active areas: (1) Soria Moria and (2) Gallionella Garden & Trollveggen. The Trollveggen vent field is located at depths of 700-750 m. Venting takes place mainly through white smoker chimneys with fluid temperatures reaching up to 260-270°C. Here we present mineralogical and geochemical data from vent chimneys and metalliferous sediments collected at the Trollveggen vent field with an ROV. Cross-sections of chimneys present evident mineralogical zonation, showing acicular barite crystals in the outer parts and sulfide enrichments in the interior (Sph + Cpy +/- Py - Po). Sediments are mainly formed by vent fragments but also by minerals precipitated by diffuse fluid circulation, showing a mineral assemblage similar to that of chimneys. Microprobe analyses were obtained both in sulfates and sulphides revealing a particular sphalerite composition, characterized by low Fe (< 2%) and high total trace metal contents (up to 4%, including Cu, Ag and Au). Geochemical profiles of gravity cores collected in the area surrounding Jan Mayen were also performed in order to investigate the presence of additional hydrothermal activity in the area. Total geochemical analyses showed a slight enrichment in trace metals, such as Cu, Zn and Fe, with exception of one core that reached 85 ppm for Cu, 150 ppm for Zn and 20% for Fe. The metal enrichment in this core suggests hydrothermal activity in the neighboring area.

Thermal Safety of the Current Buses in the Chimney of the D0 Solenoid

International Nuclear Information System (INIS)

Smith, R.P.

1998-01-01

The thermal and electrical behaviour of the current buses in the chimney of the D0 solenoid during upset conditions is modeled to guide the selection of trip levels for magnet protection circuits which discharge the magnet if abnormal conditions are detected. The current buses in the chimney are designed to operate safely without likelihood of loss of superconductivity as long as normal cooling conditions are maintained. Helium liquid level probes, helium flow instrumentation, and thermometry all are provided to certify that proper cooling conditions exist in the subcooler and chimney at all times. Rising temperatures in any portion of the system, excessive voltage drops on the vapor cooled leads, or decreasing liquid level in the subcooler or flow rate in the system, will each cause the fast discharge system to be triggered. Postulated failures of the helium flow system, somehow undetected by any and all of the aforementioned instrumentation, can in principal eventually lead to loss of superconductivity in the buses. Quenching in one bus will rapidly lead to quenching in the other. Potential taps on the buses and magnet coil halves connected to voltage-detection bridges external to the system provide at least dually redundant signals which will unambiguously trigger the magnet rapid discharge system. The conservative design of the bus system ensures that it will not be damaged during such incidents, however improbable they may be. The transition leads in the subcooler are equally conservatively designed, and would not be damaged if they were operated in a fully non-superconducting state for several minutes. The loss of liquid helium in the sub cooler required to cause this condition would imply that helium flow from the magnet had stopped, which in turn would imply that flow to the magnet had also stopped. The lack of flow into the sub cooler would result in insufficient flow to the vapor cooled leads. Any or all of these conditions would be detected, as would

Measurement of particles at wood combustion - comparison of measurements in chimney and dilution tunnel; Partikelmaetning vid vedeldning - Jaemfoerelse mellan provtagning i skorsten och spaedtunnel

Energy Technology Data Exchange (ETDEWEB)

Ryde, Daniel; Johansson, Linda

2007-07-01

According to the European standard EN 303-5, particle emissions are measured during testing of wood fired boilers. However, it is possible to measure these emissions using any established method. This may contribute to uncertainties when comparing data from boilers measured with different methods. In this project, particle emission measurements in hot gases in chimney (Swedish method) and in a dilution tunnel (Norwegian method) are compared.The value of the ratio between particulate emissions (PM) measured in the dilution tunnel and PM measured in the chimney varied between 2 and 10, while the specific CO emission was 4 - 140 g/kg dry wood supplied. The more unfavourable combustion conditions, the larger difference between the measurement methods was seen. Furthermore, different measurements at the same case were more scattered at poor combustion conditions. Consequently, it is very important to consider if particle emission data have been measured in the chimney or in a dilution tunnel when using emission data from domestic wood combustion

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

Single-center mid-term experience with chimney-graft technique for the preservation of flow to the supra-aortic branches.

Science.gov (United States)

Shahverdyan, Robert; Mylonas, Spyridon; Gawenda, Michael; Brunkwall, Jan

2018-04-01

Objectives To investigate the feasibility and the mid-term outcomes of the chimney-graft technique for the revascularization of supra-aortic branches in patients with thoracic aortic pathologies involving the aortic arch. Methods A retrospective analysis of a prospectively maintained database between January 2010 and July 2016 was performed. Primary endpoints were 30-day and overall mortality. Secondary endpoints were technical success, target vessel patency, stroke/transitory ischemic attack and type I/III endoleak rate. Results A total of 30 patients (80% male, median age 70.0 years) were treated using the chimney-graft technique for the supra-aortic branches. The indication was a degenerative aneurysm in nine patients (32%) and a type B Stanford aortic dissection and a penetrating aortic ulcer in the descending aorta in seven patients (23%), respectively. In six patients (20.0%), the indication was an type Ia endoleak after previous endovascular thoracic repair, whereas a pseudoaneurysm after previous open repair of the descending aorta was the indication in one patient (3%). Twenty-three patients (77%) were treated electively, five (17%) emergently and two (7%) urgently because of free rupture. Technical success was achieved in 90% of patients. The 30-day/in-hospital mortality was 17% (5/30). A retrograde dissection was presented in five patients. Four patients experienced a cerebrovascular event. Eight patients had type Ia endoleak and 10 had type II. During the median follow-up of 16 months (range: 0-56), four further patients died: one in respiratory insufficiency, one due to a ruptured abdominal aortic aneurysm, one in meningitis and the last one for unknown reason. The chimney-graft patency was 100%. According to the Kaplan-Meier curve, the estimated survival at one year was 66 ± 9%. Conclusions The chimney-graft technique, despite a technically demanding strategy, is a useful tool as bailout procedure in our armamentarium for high-risk patients

Uranium prospecting in alkaline mountain chimneys of Serra Negra and Salitre - Minas Gerais, Brasil

International Nuclear Information System (INIS)

Souza Filho, J.G.C.

1974-01-01

The occurence of radioactive minerals such as apatite and pyrochlore, in the alkaline chimneys of Serra Negra and Salitre (Minas Gerais, Brazil), is discussed. Also mentioned are other minerals of interest associated with the alkaline magma such as columbite, fluorite, monazite, zircon, baddeleyite, etc, which in favourable conditions may occur in deposits of great economical value, and which may present high contents of rare earths, thorium and uranium

A Novel Chimney Approach for Management of Horseshoe Kidney During EVAR

Directory of Open Access Journals (Sweden)

K. Sharma

Full Text Available Introduction: Abdominal aortic aneurysms (AAAs with coexisting horseshoe kidney (HSK can be difficult to repair, with variable blood supply from the aorta and iliac/mesenteric vessels. Endovascular aneurysm repair (EVAR has become a popular, less invasive approach to aneurysm care, and a chimney approach to EVAR (ChEVAR has expanded its use to more complex anatomy. It is mandatory to maintain adequate perfusion to the HSK and visceral branches as part of the treatment of an AAA. Report: A 61-year-old male with an HSK was incidentally found to have an infrarenal AAA that measured 6 cm on a non-contrast computed tomography (CT scan performed originally for a urologic complaint. A diagnostic angiogram was performed to define arterial anatomy and he was found to have a large inferior mesenteric artery (IMA arising 1 cm above the level of the aneurysm. ChEVAR was performed to preserve the IMA and flow to the HSK with a completion angiogram revealing patent renal arteries, IMA, and no evidence of an endoleak. Follow-up CT imaging demonstrated a Type II endoleak that resolved upon partial nephrectomy for a right-sided transitional cell carcinoma with resection of the arterial blood supply feeding the Type II endoleak. Discussion: IMA preservation via ChEVAR is technically feasible and was crucial to preserve blood supply via the IMA to the HSK. Partial nephrectomy treated the transitional cell carcinoma and resolved the Type II endoleak requiring no additional endovascular intervention. A unique treatment course demonstrated the benefits of less invasive interventions when repairing AAA with an HSK. Keywords: EVAR, Abdominal aortic aneurysm, Inferior mesenteric artery, Snorkel, Chimney, Endoleak

Experience of the remote dismantling of the Windscale advanced gas-cooled reactor and Windscale pile chimneys

International Nuclear Information System (INIS)

Wright, E.M.

1993-01-01

This paper gives brief descriptions of some of the remote dismantling work and equipment used on two large decommissioning projects: the BNFL Windscale Pile Chimneys Project (remote handling machine, waste packaging machine, remotely controlled excavator, remotely controlled demolition machine) and the AEA Windscale Advanced Gas-cooled Reactor Project (remote dismantling machine, operational waste, bulk removal techniques, semi-remote cutting operations)

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)

Ketelsen, Dominik; Kalender, Guenay; Heuschmid, Martin; Syha, Roland; Mangold, Stefanie; Claussen, Claus D.; Brechtel, Klaus

2011-01-01

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.

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.

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.

Effect of surface radiation on natural convection in an asymmetrically heated channel-chimney system

Science.gov (United States)

Nasri, Zied; Derouich, Youssef; Laatar, Ali Hatem; Balti, Jalloul

2018-05-01

In this paper, a more realistic numerical approach that takes into account the effect of surface radiation on the laminar air flow induced by natural convection in a channel-chimney system asymmetrically heated at uniform heat flux is used. The aim is to enrich the results given in Nasri et al. (Int J Therm Sci 90:122-134, 2015) by varying all the geometric parameters of the system and by taking into account the effect of surface radiation on the flows. The numerical results are first validated against experimental and numerical data available in the literature. The computations have allowed the determination of optimal configurations that maximize the mass flow rate and the convective heat transfer and minimize the heated wall temperatures. The analysis of the temperature fields with the streamlines and the pressure fields has helped to explain the effects of surface radiation and of the different thermo-geometrical parameters on the system performances to improve the mass flow rate and the heat transfer with respect to the simple channel. It is shown that the thermal performance of the channel-chimney system in terms of lower heated wall temperatures is little affected by the surface radiation. At the end, simple correlation equations have been proposed for quickly and easily predict the optimal configurations as well as the corresponding enhancement rates of the induced mass flow rate and the convective heat transfer.

The Balkan Theme in The Secret of Chimneys

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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

Functional Assessment of the Hautmann Ileal Neobladder with Chimney Modification Using Uroflowmetry and a Questionnaire

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Yong Seong Lee

2016-01-01

Full Text Available Urinary diversion reconstruction is essential after radical cystectomy and neobladder reconstruction is accepted as a fine option. This study included 51 patients, who underwent radical cystectomy with orthotopic neobladder reconstruction by a Hautmann ileal neobladder with chimney modification from 2006 to 2014. Functional outcomes were evaluated using a questionnaire and uroflowmetry. Perioperative complications were analyzed retrospectively. The mean follow-up period was 36.1 months. Eighty-six percent of patients voided without clean intermittent catheterization (CIC assistance. CIC was used 1-2x per day or every time they voided in 8% and 6% of patients, respectively, and 71% of patients were continent. The percentages of patients who used 1, 2, 3-4, and ≥5 pads per day were 15%, 6%, 2%, and 6%, respectively. Daytime and nighttime continence were achieved in 86% and 69% of patients, respectively. Daily mucus leakage was reported in 69% of patients. The mean maximum neobladder capacity, voided volume, postvoid residual volume, and maximum flow rate were 413.2 mL, 370.6 mL, 43.7 mL, and 20.8 mL/s, respectively. Eighteen early and 5 late complications developed in 13 and 5 patients, respectively. Reoperations were needed in 7 patients. The Hautmann ileal neobladder with chimney modification provided satisfactory results regarding functional outcomes.

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.

restricted fluid-seawater mixing, which causes relatively high-temperature formation of the intermediate layers. Whereas the innermost layer bordering the chimney orifice is characterized by more silica and a higher Sr-to-Ba ratio (SrO/BaO = 0.023), could...

Numerical analysis of the actual airflow in a solar chimney; Analise numerica do escoamento real de ar em uma chamine solar

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Andre G.; Cortez, Marcio F.B.; Valle, Ramon M.; Brasil, Cristiana S. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Mecanica]. E-mail: ferreira@demec.ufmg.br; fonteboa@demec.ufmg.br; ramon@demec.ufmg.br; tite@demec.ufmg.br

2000-07-01

This paper presents a numerical analysis of the turbulent natural convection of the airflow in a solar chimney, under actual solar radiation conditions. The solar chimneys are devices that consist of a transparent radial cover and of a tubular tower positioned in its center. The ground absorbs part of the incident solar radiation on the cover, heating the air in the greenhouse and inducing an upward airflow on the tower. It was developed a model that allows the evaluation of the ground temperature as a function of an energetic balance involving the incident solar radiation. The flow is described by the conservation laws for mass, momentum and thermal energy and the transport equations for the turbulence model (k and e ). A computational code using the Finite Volume Method in Generalized Coordinates was developed to solve these equations. Outlet dimensionless parameters are presented as functions of the radiation time and conditions, besides the unsteady behavior of the ground surface temperature. (author)

Real chimney technique for total debranching of supra-aortic trunks.

Science.gov (United States)

Kato, Masaaki; Kagaya, Hideo; Kubo, Yoji; Banno, Hiroshi; Ohkubo, Nobukazu

2015-02-01

Side-clamping of the ascending aorta is an indispensable technique for proximal anastomosis in total debranching of supra-aortic trunks and in endovascular aneurysm repair for arch aneurysm. However, this procedure may lead to the dislodging of multiple plaques and to clamp injury of the ascending aorta. We developed a clampless technique to achieve proximal anastomosis between the ascending aorta and an artificial graft used for total debranching of supra-aortic trunks. We applied this method in six patients with arch aneurysm and a plaque-rich ascending aorta and were able to achieve total debranching of the supra-aortic trunks in all of the patients without side-clamping the ascending aorta and no procedurally related complications. This clampless anastomosis technique ("real chimney technique") in the ascending aorta is a valuable option for total debranching of supra-aortic trunks in the hybrid repair of arch aneurysms. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Preliminary Study of Solar Chimney Assisted Cooling System for SMART

Energy Technology Data Exchange (ETDEWEB)

Lee, Byung Il; Park, Seong Jun; Lee, Young Hyeon; Park, Hyo Chan; Park, Youn Won [BEES Inc., KAIST, Daejeon (Korea, Republic of)

2016-05-15

In this paper, the possibility of application for a complete passive final heat removal system using a solar chimney power plant for SMART NPP was estimated. Additionally the size of the cooling system was approximately calculated under the some assumptions. In order to estimate the applicability of SCPP as a complete passive secondary cooling system for SMART, we try to calculate the size of heat exchanger and simulate SCPP performance. As a result, it was found that SCPP could be coupled with SMART and some of waste heat could be recovered into electricity without any change in SCPP size. The related all parameters satisfying the constraint of the final heat removal system for SMART were calculated. Using the constraint of the amount of heat to be removed from SMART, two kinds of SCPP performances were analyzed; one for a stand alone SCPP in Fig 8(a) and second for SCPP with SMART in Fig 8(b)

Dynamic wind interference effects between high chimneys

International Nuclear Information System (INIS)

Ruscheweyh, H.; Traetner, A.

2000-01-01

In an extensive wind tunnel study vortex-induced cross-wind vibrations of chimneys in a row and in grouped arrangements have been investigated. Most of the model tests have been executed in the subcritical Reynolds number range. In order to indicate the influence of the Reynolds number, some tests have been executed at simulated transcritical Reynolds number range in the large wind tunnel NKl in Dresden. It could be shown, that the exciting forces at stacks in a row and in grouped arrangements are multiple larger in the subcritical range than in the transcritical range and cannot be transferred to full-scale concrete stacks. On the contrary the variation of the Strouhal number versus distance ratio is less influenced by the Reynolds number. It could be verified, that the diameter ratio d 2 /d 1 of the luff-side stack to the lee-side stack is of major importance. A recommendation for the estimation of vortex-induced vibrations of concrete stacks in a row and in grouped arrangements could be developed from the results with simulated transcritical Reynolds number. Strouhal number factors, ψ s , and exciting force factors, ψ lat , could be evaluated in dependency of the distance ratio a/d 1 of the stacks. A proposal for practical application is given in Fig. 10 and 11. It is compared with the proposal for stacks in a row which is given in the German Standard DIN 4133 for steel stacks. (orig.) [de

Innovative chimney-graft technique for endovascular repair of a pararenal abdominal aortic aneurysm.

Science.gov (United States)

Galiñanes, Edgar Luis; Hernandez-Vila, Eduardo A; Krajcer, Zvonimir

2015-02-01

After abdominal aortic aneurysm repair, progressive degeneration of the aneurysm can be challenging to treat. Multiple comorbidities and previous operations place such patients at high risk for repeat surgery. Endovascular repair is a possible alternative; however, challenging anatomy can push the limits of available technology. We describe the case of a 71-year-old man who presented with a 5.3-cm pararenal aneurysm 4 years after undergoing open abdominal aortic aneurysm repair. To avoid reoperation, we excluded the aneurysm by endovascular means, using visceral-artery stenting, a chimney-graft technique. Low-profile balloons on a monorail system enabled the rapid exchange of coronary wires via a buddy-wire technique. This novel approach facilitated stenting and simultaneous angioplasty of multiple visceral vessels and the abdominal aorta.

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

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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

Study of the chimney produced by an underground nuclear explosion; Etude de la cheminee creee par une explosion nucleaire souterraine

Energy Technology Data Exchange (ETDEWEB)

Derlich, S [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1969-07-01

Underground nuclear explosions lead to the formation of a cavity which is roughly of spherical shape. The roof of this cavity is unstable and collapses in most cases, leading to the formation of a chimney. The height and the diameter depend on the energy of the charge and on the nature of the surroundings. The chronology of the various stages can be determined by seismic observations. The interior of the chimney is filled, either partially or completely, with rubble earth. This phenomenon is of great importance as far as the use of nuclear explosions for industrial applications is concerned. (author) [French] Les explosions nucleaires souterraines creent une cavite de forme grossierement spherique. La voute de cette cavite est instable et s'effondre dans la plupart des cas, donnant lieu a la formation d'une cheminee. La hauteur et le diametre sont fonction de l'energie du tir et de la nature du milieu. La chronologie des evenements peut etre determinee par des observations seismiques. L'interieur des cheminees est occupe, en partie ou en totalite, par des eboulis. Ce phenomene presente un grand interet pour l'utilisation des explosions nucleaires a des fins industrielles. (auteur)

An Equivalent Beam Model for the Dynamic Analysis to a Feeding Crane of a Tall Chimney. Application in a Coal Power Plant

Directory of Open Access Journals (Sweden)

Viorel-Mihai Nani

2016-05-01

Full Text Available The paper presents a dynamic analysis for a special crane, which serves a coal power plant. The steel cables for the lifting mechanisms of crane are long and flexible. For this reason, when is feeding the tall chimney, its can appear dangerous dynamic effects due to the suspended load. This load can perform oscillations or vibration movements. As a result, the suspended load position is sometimes difficult to control. Through experimental researches, using a special fitting with strain gauges and accelerometers assembled along the crane’s arm as a beam, we have obtained relevant information. Using the initial design data, we were able to develop an optimal nonlinear dynamic model. This one was the experimental support for other simulations in extremely dangerous situations, like: the accidental fall of the suspended load from the crane hook or a mechanical strong shock due to the collision between the suspended load and the tall chimney wall or the power plant wall, under the strong wind conditions, for example.

Numerical analysis of the turbulent natural convection in a solar chimney; Analise numerica da conveccao natural turbulenta em uma chamine solar

Energy Technology Data Exchange (ETDEWEB)

Brasil, Cristiana S.; Valle, Ramon M.; Cortez, Marcio F.B.; Ferreira, Andre G. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Mecanica]. E-mail: tite@demec.ufmg.br; ramon@demec.ufmg.br; fonteboa@demec.ufmg.br; ferreira@demec.ufmg.br

2000-07-01

This paper presents a theoretical analysis of the turbulent natural convection in a solar chimney operating in steady flow, with prescribed conditions of temperature in the ground. The solar radiation heats the air under the cover, which flows to the tower without artificial pumping. The hot air produced may be used to dry several agricultural products. The numerical analysis of the natural convection in this kind of dryer has fundamental importance on the design and building of this device. The mathematical model includes the conservation laws for mass, momentum and thermal energy and the transport equations for the turbulence model variables (k and e ). The k- e model of turbulence with wall functions was used. A computational code using the Finite Volume Method in Generalized Coordinates was developed to solve the system of equations that describes thermal and hydro dynamically the flow. The velocity and temperature fields are shown to the flow in the solar chimney. With geometrical alterations on the device, one can obtain a detailed description of the flow, which allow the guideline for a suitable configuration to build an experimental prototype. (author)

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%.

Advanced endografting techniques: snorkels, chimneys, periscopes, fenestrations, and branched endografts.

Science.gov (United States)

Kansagra, Kartik; Kang, Joseph; Taon, Matthew-Czar; Ganguli, Suvranu; Gandhi, Ripal; Vatakencherry, George; Lam, Cuong

2018-04-01

The anatomy of aortic aneurysms from the proximal neck to the access vessels may create technical challenges for endovascular repair. Upwards of 30% of patients with abdominal aortic aneurysms (AAA) have unsuitable proximal neck morphology for endovascular repair. Anatomies considered unsuitable for conventional infrarenal stent grafting include short or absent necks, angulated necks, conical necks, or large necks exceeding size availability for current stent grafts. A number of advanced endovascular techniques and devices have been developed to circumvent these challenges, each with unique advantages and disadvantages. These include snorkeling procedures such as chimneys, periscopes, and sandwich techniques; "homemade" or "back-table" fenestrated endografts as well as manufactured, customized fenestrated endografts; and more recently, physician modified branched devices. Furthermore, new devices in the pipeline under investigation, such as "off-the-shelf" fenestrated stent grafts, branched stent grafts, lower profile devices, and novel sealing designs, have the potential of solving many of the aforementioned problems. The treatment of aortic aneurysms continues to evolve, further expanding the population of patients that can be treated with an endovascular approach. As the technology grows so do the number of challenging aortic anatomies that endovascular specialists take on, further pushing the envelope in the arena of aortic repair.

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.

Mineralogical zonation and radiochronological relations in a large sulfide chimney from the East Pacific Rise at 18 degrees 25 minutes S

International Nuclear Information System (INIS)

Marchig, V.; Rosch, H.; Lalou, C.; Brichet, E.

1988-01-01

The top metre of a large inactive sulfide chimney from a hydrothermal field in the central Graben of the East Pacific Rise has been investigated using mineralogical, geochemical and 210 Pb/Pb dating methods. Four main mineralization stages have been identified. From age determinations, as well as chemical and mineralogical studies, it is concluded that the hydrothermal activity is either a continuous process with cyclical maxima of activity, or a discontinuous process. (43 refs., 4 tabs., 6 figs.)

Merging and elevation of ventilation chimneys as method to reduce odour nuisance from pig production

DEFF Research Database (Denmark)

Bjerg, Bjarne Schmidt

they can use standard curves that gives the required distance to neighbours calculated at standardized preconditions. If the thresholds are not met, the farmer can include environmental technologies mentioned on a special list maintained by the environmental authorities. Currently biological air cleaners...... are the sole technology mentioned on the list that significantly can reduces the odour emission and the consequent required distance to the neighbours. An alternative to the relative expensive biological air cleaners is to release the air at a larger height which increases the dilution of odour before...... of this work is to enlighten the potential of merging and elevation of ventilation chimneys in order to reduce odour concentration around large pig production facilities. The analyses are based on an assumed facility with an installed ventilation capacity of 720000 m3 h -1, which, in the reference case...

A current systematic evaluation and meta-analysis of chimney graft technology in aortic arch diseases.

Science.gov (United States)

Ahmad, Wael; Mylonas, Spyridon; Majd, Payman; Brunkwall, Jan Sigge

2017-11-01

The aim of this study was to provide a review of the literature on the use of chimney graft (CG) technique in treating arterial diseases of the aortic arch and to extrapolate conclusions by summarizing the reported outcomes in a meta-analysis. An extensive electronic search was made using PubMed/MEDLINE, Science Direct Databases, and the Cochrane Library. Included in this meta-analysis were all papers published up to February 2016 on endovascular chimney technique in the arch vessels with or without adjunct extra-anatomic debranching, in any language, providing data about at least one of the essential outcomes: early and late type I endoleak, 30-day mortality rate, development of perioperative stroke, patency, and retrograde aortic dissection. Of the 478 reports yielded by the electronic search, a total of 11 publications (on 373 patients and 387 CGs) fulfilled the inclusion criteria and were included in this study. The overall estimated proportion of technical success was 91.3% (95% confidence interval [CI], 87.4%-94.0%). Of the 373 patients, 26 (7%) experienced a type Ia endoleak in the perioperative period. The overall estimated proportion of early type Ia endoleak was 9.4% (95% CI, 6.5%-13.4%). Among the 10 studies that provided data, a retrograde type A dissection was observed in 2 of 351 patients, resulting in an overall estimated proportion of 1.8% (95% CI, 0.8%-4.0%). The pooled 30-day mortality rate was 7.9% (95% CI, 4.6%-13.2%). The pooled estimation for reintervention was 10.6% (95% CI, 5%-21%); for major stroke, 2.6% (95% CI, 1.3%-5.0%); for early patency, 97.9% (95% CI, 95.8%-99%); and for late patency, 92.9% (95% CI, 87.3%-96%). Treatment of aortic diseases involving the aortic arch poses a great challenge. The CG technique has been applied as an alternative treatment option. This meta-analysis shows that endovascular repair of aortic arch disease using a CG technique in the aortic arch vessels is technically feasible and effective but not without

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

A study of the various baffles used in the Marcoule chimneys and the search for a new model (1961); Etude des differents deflecteurs utilises pour les cheminees de Marcoule et recherche d'un nouveau type de deflecteur (1961)

Energy Technology Data Exchange (ETDEWEB)

Chassany, J [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires; Parigi, H [Institut de Mecanique des Fluides de Marseille, 13 (France); Salaun-Penquer, G [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France)

1961-07-01

The baffle placed at the top of a chimney determines the shape of the smoke pall for low exit-velocities. The G. 1 type baffle was studied taking into account the characteristics of its collar: totally hollow - partially hollow - solid; on a ribbed chimney or on a plain chimney. The Pu type baffle was also tested. The search for a new type of baffle was limited to variants of the blade - type baffle: - a porous envelope device; - a cone - shaped device and - a deflector of the cupel type. Only the blade-type baffle was rejected, efficient solutions are proposed using the other types or their combinations. (authors) [French] Le deflecteur place au sommet d'une cheminee conditionne l'allure du panache pour les rejets a faible vitesse de sortie. Le deflecteur type Gl a ete etudie en tenant compte de son embase: totalement evidee - partiellement evidee - pleine; sur une cheminee striee et sur une cheminee lisse. Le deflecteur type Pu a ete egalement teste. La recherche d'un nouveau type de deflecteur a porte sur les deflecteurs a aubage: - un dispositif a enveloppe poreuse; - un dispositif en ogive et - le deflecteur en coupelle. Seul le deflecteur a aubage a ete rejete, des solutions efficaces sont proposees avec les autres types ou leur combinaison. (auteurs)

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.

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)

Behr, T.M.; Gratz, S.; Markus, P.M.; Dunn, R.M.; Huefner, M.; Becker, H.; Becker, W.

1997-01-01

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

The Guaymas Basin hiking guide to hydrothermal mounds, chimneys and microbial mats: complex seafloor expressions of subsurface hydrothermal circulation

Directory of Open Access Journals (Sweden)

Andreas eTeske

2016-02-01

Full Text Available 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 heatflow gradients. Recognizing the inherent spatial limitations of much current Guaymas Basin sampling calls for a wider survey of the entire spreading region.

A First Approach to Natural Thermoventilation of Residential Buildings through Ventilation Chimneys Supplied by Solar Ponds

Directory of Open Access Journals (Sweden)

Ferdinando Salata

2015-07-01

Full Text Available The exploitation of natural ventilation is a good solution to improve buildings from an energetic point of view and to fulfill the requirements demanded by the thermohygrometric comfort and the air quality in enclosed spaces. Some past researches demonstrated how some devices, useful to this purpose, follow the principles of solar chimneys and are able to move air masses while exploiting the Archimedes thrust. The natural ventilation must be supplied by a flow moving upward, generated by a heat source performing at temperatures slightly higher than the one present in the environment. To have a minimum energetic effect, the heat can be extracted from solar ponds; solar ponds are able to collect and store solar energy in the geographical regions characterized by sufficient values of solar radiation. Thus it is possible, in summer, to provoke a nocturnal natural ventilation useful for the air change in indoor spaces (in those climatic areas where, during the night, there is a temperature gradient.

Antecedent and progress of the project on the treatment of chimney gases with electrons in Mexico

International Nuclear Information System (INIS)

Pina V, G.

1991-10-01

After the realization of the chimney gases treatment seminar with electrons, organized jointly among the National Institute of Nuclear Research (ININ) and the International Atomic Energy Agency (IAEA), in August of 1990 and following one of the received recommendations, it was elaborated an economic technical feasibility study of this process in Mexico, using technical data of a thermoelectric power station of Federal Commission of Electricity, where is being consumed fuel oil. This study is good to know some technical parameters of a plant of this process, proposed to settle in Mexico, so as some economic estimates of installation and operation costs of this plant; also, it is traced about the construction of a demonstration plant of the process, with capacity of 20,000 m 3 N/h, using the same data of the thermoelectric power station considered previously, as the first step in the scaling of this process toward industrial level. (Author)

Experimental investigation into heating and airflow in trombe walls and solar chimneys

International Nuclear Information System (INIS)

Habib, A.; Burek, S.

2006-01-01

Trombe Walls and solar chimneys are examples of passive solar air heating systems. However, the airflow and thermal efficiency characteristics of this type of system are not well understood, and partly for this reason, they are not commonly utilised. This paper reports on an experimental investigation into buoyancy-driven convection in a test rig designed to simulate the operation of a passive solar collector. The test rig comprised a vertical open-ended channel, approximately 1a square, heated from one side. The channel depth could be varied from 20mm to 110mm, and heating inputs varied from 200W to 1000W. Temperatures and airflow rates were measured and recorded, to characterise both steady-state and transient performance. The principal findings are: 1. Time constants (for heating)ranged typically between 30 and 70 minutes. 2. Flow regimes were mainly laminar (Reynolds number varing from ∼500 to ∼4000, depending on heat input and channel depth. 3. The thermal efficiency (as a solar collector and the heat transfer coefficient were functions of heat input, and were not depended on the channel depth. 4. The mass flow rate through the channel increased bath as the heat input increased and as the channel depth increased. The paper presents these findings and discusses their implications in more detail.(Author)

Cracked reinforced concrete walls of chimneys, silos and cooling towers as result of using formworks

Directory of Open Access Journals (Sweden)

Maj Marek

2018-01-01

Full Text Available There are presented in this paper some problems connected with reinforced concrete shell objects operation in the aggressive environment and built in method of formworks. Reinforced concrete chimneys, cooling towers, silos and other shells were built for decades. Durability of cracked shells are one of the most important parameters during process of designing, construction and exploitation of shells. Some reasons of appearance of horizontal and vertical cracks as temperature, pressure of stored material, live loads e.g. dynamic character of wind, moisture, influence of construction joints, thermal insulation, chemistry active environmental etc. reduce the carrying capacity of the walls. Formworks, as is occurred recently, are the reason for technological joints with leaking connection, imperfections of flexible formworks slabs and as result can initiate cracks. Cracked surface of this constructions causes decreasing capacity and lower the state of reliability. Horizontal, vertical cracks can caused corrosion of concrete and steel bars, decreasing stiffness of contraction, increasing of deflection and carbonation of concrete cover. Local and global imperfactions of concrete shells are increasing according to greater number of cracks...

Theoretical study on air flow in a solar chimney with real insulation conditions; Estudo teorico do escoamento de ar em uma chamine solar com condicoes reais de insolacao

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Andre Guimaraes; Cortez, Marcio Fonte-Boa; Molina Valle, Ramon; Brasil, Cristiana Santiago [Minas Gerais Univ., Belo Horizonte, MG, (Brazil). Dept. de Engenharia Mecanica]. E-mail: ferreira@demec.ufmg.br

2000-07-01

This paper presents a theoretical analysis of the turbulent air flow with real conditions of insulation inside a solar chimney. The flow is described by the mass, momentum and energy conservation equations, besides the transport equations of the quantities in the turbulence model (k and epsilon). Dimensionless parameters are presented at way out the device, as function of time and the insulation conditions, represented by the soil and the roof heating.

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.)

Multidimensional analysis of developing two-phase flows in an ESBWR chimney with and without riser channels

International Nuclear Information System (INIS)

Murakawa, H.; Antal, S.P.; Lahey, R T.

2008-01-01

The object of this work was to simulate developing multidimensional velocity and void fraction distributions in bubbly and churn turbulent two-phase flows. An advanced Computational Multiphase Fluid Dynamics (CMFD) code, NPHASE, was used to perform three-dimensional, multi-field simulations of the developing phasic velocity and phase distributions in vertical adiabatic conduits. The NPHASE code employed a multi-field two-fluid model, in which, for churn turbulent flow, the vapor phase was divided into small and large, cap bubble fields. In addition, state-of-the-art interfacial area density and field-to-field mass transfer models were used for both the small and large, cap bubbles. In particular, the bubble breakup and coalescence processes were quantified using a two-group interfacial area density transport equation. This allowed the CMFD simulation of developing churn turbulent flows in an ESBWR with and without vertical riser channels in the chimney region above the core. Based on these simulations it was concluded that riser channels have little adverse effect on the induced natural circulation flow through the core and the stability characteristics of an ESBWR. (authors)

Chimney Technique in Supra-Aortic Branch Reconstruction in China: A Systematic and Critical Review of Chinese Published Experience.

Science.gov (United States)

Zhao, Yang; Shi, Yawei; Wang, Mian; Cui, Jin; Chen, Yitian; Zheng, Liang; Yin, Henghui; Chang, Guangqi

2017-08-01

The chimney graft (CG) technique has been proposed as a complete endovascular supra-aortic branch reconstruction for aortic pathologies. Due to the rapid growth of thoracic endovascular aortic repair (TEVAR) in China, we aimed to investigate the current data of the CG technique in this most populous country. Studies of supra-aortic branch reconstruction using the CG technique from Chinese centers were collected and analyzed. A total of 294 patients from Chinese centers who underwent TEVAR with CGs were included. There were 301 CGs performed, with a technical successful rate of 97.7%. The rate of early type I endoleaks was 7.1%, and the patency rate of the CGs was desirable. Balloon-expandable bare CGs were significantly associated with good early outcomes and a low rate of endoleaks. Current data from China revealed positive outcomes using CGs for supra-aortic branch reconstruction. Balloon-expandable bare CGs may be the first choice according to the data available but should be considered with caution.

Influence of Anatomic Angulations in Chimney and Fenestrated Endovascular Aneurysm Repair.

Science.gov (United States)

Caradu, Caroline; Bérard, Xavier; Midy, Dominique; Ducasse, Eric

2017-08-01

The lack of widespread availability of Fenestrated endovascular aneurysm repair (F-EVAR) encouraged alternative strategies. Hence, Chimney graft (CG)-EVAR spread when costs, manufacturing delays, or anatomy preclude F-EVAR. Our objective is to evaluate CG- and F-EVAR outcomes depending on the angulation of target renal arteries and hostility of iliac accesses in order to determine the potential impact of a choice made between both techniques on the basis of preoperative anatomic criteria. Consecutive patients treated by CG-EVAR or F-EVAR, from January 2010 to January 2015, were considered for inclusion. Anatomic parameters were defined by preoperative computed tomography angiography. A subgroup analysis was performed depending on renal arteries' angulation (cut-off: -30°) and iliac arteries' hostility (cut-off: diameter renal artery was shorter in the CG group (11.7 ± 6.2 mm vs. 14.1 ± 5.9 mm, P = 0.06). Longitudinal angulation of the right renal artery was not statistically different between both groups, while the left renal artery presented with a significantly more downward angulation in the CG group (-32.0 ± 15.3 vs. -19.0 ± 19.6, P = 0.003). There were significantly more grade 3 iliac tortuosity indexes for CG-EVAR (P = 0.03) with significantly smaller external iliac diameters (7.8 ± 1.7 vs. 8.8 ± 1.6 mm, P = 0.0009). There was 1 renal artery early occlusion in the renal artery angulation and diameter, iliac artery hostility, and aortic neck length among other parameters may help the surgeon make a decision toward the endovascular strategy that seems best suited for each specific patient. Copyright © 2017 Elsevier Inc. All rights reserved.

Quantitative estimation of massive gas hydrate in gas chimney structures, the eastern margin of Japan Sea, from the physical property anomalies obtained by LWD.

Science.gov (United States)

Tanahashi, M.; Morita, S.; Matsumoto, R.

2017-12-01

Two dedicated LWD (Logging While Drilling) cruises, GR14 and HR15, were conducted in summers of 2014 and 2015, respectively, by Meiji University and Geological Survey of Japan, AIST to explore the gas chimney structures, which are characterized by the columnar acoustic blanking below the topographic mound and/or pockmarks in eastern margin of Japan Sea. Shallow (33 to 172m-bsf, average 136m-bsf) 33 LWD drillings were carried out generally in and around gas chimney structures which are in Oki Trough, Off-Joetsu, and Mogami Trough areas, eastern margin of Japan Sea, during two cruises. Schlumberger LWD tools, GeoVISION (resistivity), TeleScope, ProVISION (NMR) and SonicVISION (sonic) were applied during GR14. NeoScope (neutron) was added and SonicScope was replaced for SonicVISION during HR15. The presence of thick highly-anomalous intervals within the LWD data at site J24L suggests the development of massive gas hydrate within Off-Joetsu, by very high resistivity ( 10,000 Ωm), high Vp ( 3,700 m/s) and Vs (370-1,839 m/s), high neutron porosity ( 1.2), low natural gamma ray intensity ( 0 API), low neutron gamma density ( 0.8 g/cm3), low NMR porosity ( 0.0), low permeability (10-2-10-4 mD), low formation neutron sigma (26-28). The extreme physical properties intervals suggest the development of the almost pure hydrate. Because of the clear contrast between pure hydrate and seawater saturated fine sediments, the hydrate amount can be estimated quantitatively based on the assumptions as the two component system of pure hydrate and the monotonous seawater saturated fine sediments. This study was conducted as a part of the methane hydrate research project funded by METI (the Ministry of Economy, Trade and Industry, Japan).

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

International Nuclear Information System (INIS)

Khasawneh, Khalid; PARK, Youn Won

2014-01-01

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

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

Numerical simulation of an innovated building cooling system with combination of solar chimney and water spraying system

Science.gov (United States)

Rabani, Ramin; Faghih, Ahmadreza K.; Rabani, Mehrdad; Rabani, Mehran

2014-05-01

In this study, passive cooling of a room using a solar chimney and water spraying system in the room inlet vents is simulated numerically in Yazd, Iran (a hot and arid city with very high solar radiation). The performance of this system has been investigated for the warmest day of the year (5 August) which depends on the variation of some parameters such as water flow rate, solar heat flux, and inlet air temperature. In order to get the best performance of the system for maximum air change and also absorb the highest solar heat flux by the absorber in the warmest time of the day, different directions (West, East, North and South) have been studied and the West direction has been selected as the best direction. The minimum amount of water used in spraying system to set the inside air averaged relative humidity <65 % is obtained using trial and error method. The simulation results show that this proposed system decreases the averaged air temperature in the middle of the room by 9-14 °C and increases the room relative humidity about 28-45 %.

The solar chimney. Power from solar radiation on an industrial scale; Das Aufwindkraftwerk. Strom aus der Sonne im grosstechnischen Massstab

Energy Technology Data Exchange (ETDEWEB)

Schlaich, J. [Schlaich und Partner, Beratende Ingenieure im Bauwesen, Stuttgart (Germany)

1998-04-01

The author looks at the relationships between population growth, standard of living, gross social product and energy. Development needs energy. Energy consumption grows in proportion to gross social product or prosperity, while population growth goes down exponentially. If distribution-related armed conflicts and fundamentalism are to be avoided, developing countries must be provided with energy enabling their peoples to live in dignity. Even though the required amount of energy is much smaller than the energy demand of industrialized countries, it means that world energy consumption will soar to several times what it is now. Where should this energy come from without causing the environment to collapse (because developing countries lack funds for environmental protection) and without threats to safety from nuclear power stations (because of inadequate knowledge of safety standards)? Poor countries have abundant solar radiation and large desert areas; so it is obvious to use technologically mature, large solar power plants, especially solar chimneys. They are described by means of some detailed drawings and graphs. A solar chimney corresponds in principle to a hydro-electric power station but uses hot air instead of water. Heat stored during the daytime is released during the nighttime to a 200 MW vertical-axis turbine, permitting non-stop 24-hour operation. (AKV) [Deutsch] Im Beitrag beleuchtet der Verfasser die Zusammenhaenge zwischen Bevoelkerungszuwachs, Lebensstandard, Bruttosozialprodukt und Energie. Entwicklung braucht Energie. Proportional zum Bruttosozialprodukt oder Wohlstand waechst der Energieverbrauch, waehrend der Bevoelkerungszuwachs exponentiell sinkt. Um Verteilungskriege und Fundamentalismus zu verhindern, muss den Entwicklungslaendern Energie bereitgestellt werden, so dass ein menschenwuerdiges Leben ermoeglicht wird. Obwohl diese Menge wesentlich niedriger als die den Industrielaendern bereitgestellte Energie anzusetzen ist, wuerde damit der

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

Science.gov (United States)

Smith, Kirk R; McCracken, John P; Thompson, Lisa; Edwards, Rufus; Shields, Kyra N; Canuz, Eduardo; Bruce, Nigel

2010-07-01

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 exposures and kitchen concentrations. Passive diffusion tubes originally developed for industrial hygiene applications were deployed on a quarterly basis to measure 48-hour integrated personal carbon monoxide exposures among 515 children 0-18 months of age and 532 mothers aged 15-55 years and area samples in a subsample of 77 kitchens, in households randomized into control and intervention groups. Instrument comparisons among types of passive diffusion tubes and against a continuous electrochemical CO monitor indicated that tubes responded nonlinearly to CO, and regression calibration was used to reduce this bias. Before stove introduction, the baseline arithmetic (geometric) mean 48-h child (n=270), mother (n=529) and kitchen (n=65) levels were, respectively, 3.4 (2.8), 3.4 (2.8) and 10.2 (8.4) p.p.m. The between-group analysis of the 3355 post-baseline measurements found CO levels to be significantly lower among the intervention group during the trial period: kitchen levels: -90%; mothers: -61%; and children: -52% in geometric means. No significant deterioration in stove effect was observed over the 18 months of surveillance. The reliability of these findings is strengthened by the large sample size made feasible by these unobtrusive and inexpensive tubes, measurement error reduction through instrument calibration, and a randomized, longitudinal study design. These results from the first randomized trial of improved household energy technology in a developing country and

A cost-benefit analysis of power generation from commercial reinforced concrete solar chimney power plant

International Nuclear Information System (INIS)

Li, Weibing; Wei, Ping; Zhou, Xinping

2014-01-01

Highlights: • We develop an economic model different from related models. • We evaluate the initial investment cost of a plant built in northwest China. • We analyze the cost and benefit of a plant built in northwest China. • By the sensitivity analysis, we examine the sensitivity of TNPV to many parameters. - Abstract: This paper develops a model different from existing models to analyze the cost and benefit of a reinforced concrete solar chimney power plant (RCSCPP) built in northwest China. Based on the model and some assumptions for values of parameters, this work calculates total net present value (TNPV) and the minimum electricity price in each phase by dividing the whole service period into four phases. The results show that the minimum electricity price in the first phase is higher than the current market price of electricity, but the minimum prices in the other phases are far less than the current market price. The analysis indicates that huge advantages of the RCSCPP over coal-fired power plants can be embodied in phases 2–4. In addition, the sensitivity analysis performed in this paper discovers TNPV is very sensitive to changes in the solar electricity price and inflation rate, but responds only slightly to changes in carbon credits price, income tax rate and interest rate of loans. Our analysis predicts that RCSCPPs have very good application prospect. To encourage the development of RCSCPPs, the government should provide subsidy by setting higher electricity price in the first phase, then lower electricity price in the other phases

Assessment of levelized cost of electricity for a 10-MW solar chimney power plant in Yinchuan China

International Nuclear Information System (INIS)

Guo, Penghua; Zhai, Yaxin; Xu, Xinhai; Li, Jingyin

2017-01-01

Highlights: • An unsteady model is proposed for annual power generation prediction of SCPPs. • LCOE of a 10-MW SCPP in China is estimated through a cost benefit analysis. • Cost advantage and concessional loan under conditions in China are considered. • SCPP is proven to be economically feasible under favorable conditions in China. - Abstract: Solar chimney power plant (SCPP) is a promising renewable energy technology that needs policy support and market cultivation at the early stage of its development. An accurate prediction of the levelized cost of electricity (LCOE) can be used as basis for crafting effective support policies. This study presents an unsteady theoretical model that considers hourly meteorological data and soil heat storage in estimating the annual power generation of an SCPP. A cost benefit model is adopted to calculate the LCOE of a 10-MW SCPP in Yinchuan, a representative geographical location in the Northwestern region of China. By considering the cost advantage of China, the concessional loan, as well as the low operation and maintenance cost, the LCOE of the SCPP is estimated to be 0.4178 Yuan/kWh, which can compete with those of wind power and solar PV in China. This work lays a good foundation for the accurate prediction of power generation and provides a reference for the Chinese government in crafting effective support policies for SCPPs.

Fluids emission and gas chimneys imaged in high-resolution 3D seismic: Investigating the role of sedimentary structures in controlling vertical fluid migration (offshore of Ceará-Potiguar sub-basin, Brazil).

Science.gov (United States)

Maestrelli, Daniele; Iacopini, David; Vittorio, Maselli

2017-04-01

Fluid emissions at seabed have been widely investigated during last years due to their potential in detecting new petroleum provinces and to their role in monitoring the environmental risk associated to CO2 storage and hydrocarbon leakage from the overburden. Fluid emission appears to be characterized by a variety of different processes and genetic mechanisms, and has been reported in different geological settings. We investigated a 45 by 25 km 3D seismic dataset located in the offshore Ceará state (Brazil), imaging the submarine slope system of the Potiguar sub-basin, part of the Ceará basin. The Paleogene sequence is characterized by a series of steep canyons acting as slope-bypass systems that force the transport of sediment basinward and promote the deposition in deepwater settings. The whole area seems to be affected by gravity driven processes in the form of turbidites and hyperpycnal flows that probably are responsible of the main submarine landslides observed and of the evolution of the canyons themselves. Bottom currents seem to play a key role in shaping the margin as well, by promoting the formation of sediment ridges and fields of sediment waves. In this setting, a series of widely distributed active pockmarks are observed both at the seabed and as paleo-pockmarks in the seismic subsurface, testifying the upward fluid migration and emission along gas chimneys and conduits. Active or recent pockmark varies from tens of meters up to about 2 km in diameters and are mainly circular to elliptical. A preliminary systematic mapping of those fluid escape features shows the strong control of the chutes and pools generated by fast turbidity currents on the chimney geometry pattern and fluid conduit. This evidence may suggest that the erosional/depositional features associated to turbidite sedimentation strongly control lateral permeability variations and, consequently, the vertical fluid migration.

Geochemical models of metasomatism in ultramafic systems: Serpentinization, rodingitization, and sea floor carbonate chimney precipitation

Science.gov (United States)

Palandri, J.L.; Reed, M.H.

2004-01-01

In a series of water-rock reaction simulations, we assess the processes of serpentinization of harzburgite and related calcium metasomatism resulting in rodingite-type alteration, and seafloor carbonate chimney precipitation. At temperatures from 25 to 300??C (P = 10 to 100 bar), using either fresh water or seawater, serpentinization simulations produce an assemblage commonly observed in natural systems, dominated by serpentine, magnetite, and brucite. The reacted waters in the simulations show similar trends in composition with decreasing water-rock ratios, becoming hyper-alkaline and strongly reducing, with increased dissolved calcium. At 25??C and w/r less than ???32, conditions are sufficiently reducing to yield H2 gas, nickel-iron alloy and native copper. Hyperalkalinity results from OH- production by olivine and pyroxene dissolution in the absence of counterbalancing OH- consumption by alteration mineral precipitation except at very high pH; at moderate pH there are no stable calcium minerals and only a small amount of chlorite forms, limited by aluminum, thus allowing Mg2+ and Ca2+ to accumulate in the aqueous phase in exchange for H+. The reducing conditions result from oxidation of ferrous iron in olivine and pyroxene to ferric iron in magnetite. Trace metals are computed to be nearly insoluble below 300??C, except for mercury, for which high pH stabilizes aqueous and gaseous Hg??. In serpentinization by seawater at 300??C, Ag, Au, Pd, and Pt may approach ore-forming concentrations in sulfide complexes. Simulated mixing of the fluid derived from serpentinization with cold seawater produces a mineral assemblage dominated by calcite, similar to recently discovered submarine, ultramafic rock-hosted, carbonate mineral deposits precipitating at hydrothermal vents. Simulated reaction of gabbroic or basaltic rocks with the hyperalkaline calcium- and aluminum-rich fluid produced during serpentinization at 300??C yields rodingite-type mineral assemblages, including

The Impact of the Rock Mass Deformation on Geometric Changes of a Historical Chimney in the Salt Mine of Bochnia

Science.gov (United States)

Szafarczyk, Anna; Gawałkiewicz, Rafał

2018-03-01

There are many ways of the geometry measurement of slim objects, with the application of geodetic and photogrammetric methods. A modern solution in the diagnostics of slim objects is the application of laser scanning, with the use of a scanner of a scanning total station. The point cloud, obtained from the surface of the scanned object gives the possibility of generating not only information on structural surface deformations, but also facilitates obtaining the data on the geometry of the axis of the building, as a basic indicator of the characteristics of its deformation. The cause of the change in the geometry of slim objects is the impact of many external and internal factors. These objects are located in the areas of working or closed underground mines. They can be impacted by the ground and they can face the results of the convergence of cavities. A specific structure of the salt rock mass causes subsequent convergence of the post-exploitation cavities, which has the influence on the behaviour of the terrain surface and the related objects. The authors analysed the impact of the changes in the rock mass and the surface on the changes of the industrial chimney in the Bochnia Salt Mine.

Endovascular Repair of Acute Symptomatic Pararenal Aortic Aneurysm With Three Chimney and One Periscope Graft for Complete Visceral Artery Revascularization

International Nuclear Information System (INIS)

Brechtel, Klaus; Ketelsen, Dominik; Endisch, Andrea; Heller, Stephan; Heuschmid, Martin; Stock, Ulrich A.; Kalender, Guenay

2012-01-01

PurposeTo describe a modified endovascular technique for complete revascularization of visceral and renal arteries in symptomatic pararenal aortic aneurysm (PRAA).TechniqueArterial access was surgically established in both common femoral arteries (CFAs) and the left subclavian artery (LSA). Revascularization of the left renal artery, the celiac trunk, and the superior mesenteric artery was performed through one single sheath via the LSA. Suitable covered stents were put in the aortic branches but not deployed. The right renal artery was accessed over the left CFA. Due to the longitudinal extension of the presented aneurysm two stent-grafts were introduced via the right CFA. After deploying the aortic stent-grafts, all covered stents in the side branches were deployed consecutively with a minimum overlap of 5 mm over the cranial and caudal stent-graft edges. Simultaneous ballooning was performed to fully expand all stent-grafts and warranty patency. Conclusion: This is the first report in the literature of chimney grafting in PRAA for complete revascularization of visceral and renal branches by using more than two covered stents introduced from one side through one single sheath. However this technique is modified, it should be used only in bailout situations when branched stent-grafts are not available and/or surgery is not suitable.

"Invisible" Killer

Science.gov (United States)

... crawlspace Sooting Debris or soot falling from chimney, fireplace or appliance Fireplace Rusting or water streaking on vent/chimney Loose ... panel • Sooting • Debris or soot falling from chimney, fireplace, or appliances • Loose or disconnected vent/chimney, fireplace ...

Fuel cell with internal flow control

Science.gov (United States)

Haltiner, Jr., Karl J.; Venkiteswaran, Arun [Karnataka, IN

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.

First observations of tritium in ground water outside chimneys of underground nuclear explosions, Yucca Flat, Nevada Test Site

International Nuclear Information System (INIS)

Crow, N.B.

1976-01-01

Abnormal levels of radionuclides had not been detected in ground water at the Nevada Test Site beyond the immediate vicinity of underground nuclear explosions until April 1974, when above-background tritium activity levels were detected in ground-water inflow from the tuff beneath Yucca Flat to an emplacement chamber being mined in hole U2aw in the east-central part of Area 2. No other radionuclides were detected in a sample of water from the chamber. In comparison with the amount of tritium estimated to be present in the ground water in nearby nuclear chimneys, the activity level at U2aw is very low. To put the tritium activity levels at U2aw into proper perspective, the maximum tritium activity level observed was significantly less than the maximum permissible concentration (MPC) for a restricted area, though from mid-April 1974 until the emplacement chamber was expended in September 1974, the tritium activity exceeded the MPC for the general public. Above-background tritium activity was also detected in ground water from the adjacent exploratory hole, Ue2aw. The nearest underground nuclear explosion detonated beneath the water table, believed to be the source of the tritium observed, is Commodore (U2am), located 465 m southeast of the emplacement chamber in U2aw. Commodore was detonated in May 1967. In May 1975, tritium activity May significantly higher than regional background. was detected in ground water from hole Ue2ar, 980 m south of the emplacement chamber in U2aw and 361 m from a second underground nuclear explosion, Agile (U2v), also detonated below the water table, in February 1967. This paper describes these occurrences of tritium in the ground water. A mechanism to account for the movement of tritium is postulated

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.)

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)

Bangard, Christopher; Franke, Mareike; Maintz, David; Chang, De-Hua; Pfister, Roman; Deppe, Antje-Christin; Matoussevitch, Vladimir

2014-01-01

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.)

Determining the explosion effects on the Gasbuggy reservoir from computer simulation of the postshot gas production history

International Nuclear Information System (INIS)

Rogers, Leo A.

1970-01-01

Analysis of the gas production data from Gasbuggy to deduce reservoir properties outside the chimney is complicated by the large gas storage volume in the chimney because the gas flow from the surrounding reservoir into the chimney cannot be directly measured. This problem was overcome by developing a chimney volume factor F (M 2 CF/PSI) based upon analysis of rapid drawdowns during the production tests. The chimney volume factor was in turn used to construct the time history of the required influx of gas into the chimney from the surrounding reservoir. The most probable value of F to describe the chimney is found to be 0.150 M 2 CF/PSI. Postulated models of the reservoir properties outside the chimney are examined by calculating the pressure distribution and flow of gas through the reservoir with the experimentally observed chimney pressure history applied to the cavity wall. The calculated influx from the reservoir into the chimney is then compared to the required influx and the calculated pressure at a radius of 300 feet is compared to the observed pressures in a shut-in satellite well (GB-2RS) which intersects the gas-bearing formation 300 feet from the center of the chimney. A description of the mathematics in the computer program used to perform the calculations is given. Gas flow for a radial model wherein permeability and porosity are uniform through the gas producing sand outside the chimney was calculated for several values of permeability. These calculations indicated that for the first drawdown test (July 1968) the permeability-producing height product (kh) was in the region of 15 to 30 millidarcy-feet (md-ft) and that after several months of testing, the effective kh had dropped to less than 8 md-ft. Calculations wherein (1) the permeability decreases from the chimney out to the 'fracture' radius, and (2) an increased production height is used near the chimney, match the data better than the simple radial model. Reasonable fits to the data for the

Waste chimney oil to nanolights: A low cost chemosensor for tracer metal detection in practical field and its polymer composite for multidimensional activity.

Science.gov (United States)

Das, Poushali; Ganguly, Sayan; Maity, Priti Prasanna; Bose, Madhuparna; Mondal, Subhadip; Dhara, Santanu; Das, Amit Kumar; Banerjee, Susanta; Das, Narayan Ch

2018-03-01

Proper waste disposal from household and restaurants is becoming an important and recurring waste-management concern. Herein, a method of upcycling of waste kitchen chimney oil has been adopted to prepare fluorescent multifunctional carbon quantum dots. These nanodots showed superior biocompatibility, excellent optical properties, water solubility and high yield. Preparation of C-dots from highly abundant carbon source of waste refusals is highly effective in commercial aspect as well as in reducing the immense environmental pollution. The C-dots showed quasi-spherical size obtained from high resolution transmission electron microscopy (HRTEM) having an abundance of 1-4 nm in size. The ease of water dispersibility of the nanodots is a mere reflection of their surface polarity which has been supported by Fourier transformed infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). In the field of practical acceptability, the C-dots have been experimented to sense Fe 3+ ion in a wide range of concentration (1 nM to 600 μM) with a detection limit of 0.18 nM which can be termed as 'tracer metal chemosensor'. Moreover, the prepared carbon dots were also tested against inter-cellular Fe 3+ ion sensing probe. Lastly, we also fabricate the biopolymer‑carbon dots composite for fluorescent marker ink and light emitting polymer film. Copyright © 2018 Elsevier B.V. All rights reserved.

Antecedent and progress of the project on the treatment of chimney gases with electrons in Mexico; Antecedentes y avance del proyecto de tratamiento de gases de chimenea con electrones en mexico

Energy Technology Data Exchange (ETDEWEB)

Pina V, G

1991-10-15

After the realization of the chimney gases treatment seminar with electrons, organized jointly among the National Institute of Nuclear Research (ININ) and the International Atomic Energy Agency (IAEA), in August of 1990 and following one of the received recommendations, it was elaborated an economic technical feasibility study of this process in Mexico, using technical data of a thermoelectric power station of Federal Commission of Electricity, where is being consumed fuel oil. This study is good to know some technical parameters of a plant of this process, proposed to settle in Mexico, so as some economic estimates of installation and operation costs of this plant; also, it is traced about the construction of a demonstration plant of the process, with capacity of 20,000 m{sup 3}N/h, using the same data of the thermoelectric power station considered previously, as the first step in the scaling of this process toward industrial level. (Author)

Determining the explosion effects on the Gasbuggy reservoir from computer simulation of the postshot gas production history

Energy Technology Data Exchange (ETDEWEB)

Rogers, Leo A [El Paso Natural Gas Company (United States)

1970-05-01

Analysis of the gas production data from Gasbuggy to deduce reservoir properties outside the chimney is complicated by the large gas storage volume in the chimney because the gas flow from the surrounding reservoir into the chimney cannot be directly measured. This problem was overcome by developing a chimney volume factor F (M{sup 2}CF/PSI) based upon analysis of rapid drawdowns during the production tests. The chimney volume factor was in turn used to construct the time history of the required influx of gas into the chimney from the surrounding reservoir. The most probable value of F to describe the chimney is found to be 0.150 M{sup 2}CF/PSI. Postulated models of the reservoir properties outside the chimney are examined by calculating the pressure distribution and flow of gas through the reservoir with the experimentally observed chimney pressure history applied to the cavity wall. The calculated influx from the reservoir into the chimney is then compared to the required influx and the calculated pressure at a radius of 300 feet is compared to the observed pressures in a shut-in satellite well (GB-2RS) which intersects the gas-bearing formation 300 feet from the center of the chimney. A description of the mathematics in the computer program used to perform the calculations is given. Gas flow for a radial model wherein permeability and porosity are uniform through the gas producing sand outside the chimney was calculated for several values of permeability. These calculations indicated that for the first drawdown test (July 1968) the permeability-producing height product (kh) was in the region of 15 to 30 millidarcy-feet (md-ft) and that after several months of testing, the effective kh had dropped to less than 8 md-ft. Calculations wherein (1) the permeability decreases from the chimney out to the 'fracture' radius, and (2) an increased production height is used near the chimney, match the data better than the simple radial model. Reasonable fits to the data for

Passive cooling of control rod drive mechanisms

International Nuclear Information System (INIS)

Hankinson, M.F.; Schwirian, R.E.

1992-01-01

A method and apparatus are provided for passively cooling the control rod drive mechanisms (CRDMs) in the reactor vessel of a nuclear power plant. Passive cooling is achieved by dispersing a plurality of chimneys within the CRDM array in positions where a control rod is not required. The chimneys induce convective air currents which cause ambient air from within the containment to flow over the CRDM coils. The air heated by the coils is guided into inlets in the chimneys by baffles. The chimney is insulated and extends through the seismic support platform and missile shield disposed above the closure head. A collar of adjustable height mates with plate elements formed at the distal end of the CRDM pressure housings by an interlocking arrangement so that the seismic support platform provides lateral restraint for the chimneys. (Author)

A moist air condensing device for sustainable energy production and water generation

International Nuclear Information System (INIS)

Ming, Tingzhen; Gong, Tingrui; Richter, Renaud K. de; Wu, Yongjia; Liu, Wei

2017-01-01

Highlights: • A novel device based upon a SCPP system is proposed for electricity production and water generation. • The collector is replaced by black tubes around the chimney. • The overall performance of SCPP for energy production and water generation was analyzed. • The system total energy efficiency of a SCPP with a height of 3000 m can be nearly 7%. - Abstract: A solar chimney power plant (SCPP) is not only a solar thermal application system to achieve output power, but also a device extracting freshwater from the humid air. In this article, we proposed a SCPP with collector being replaced by black tubes around the chimney to warm water and air. The overall performance of SCPP was analyzed by using a one-dimensional compressible fluid transfer model to calculate the system characteristic parameters, such as chimney inlet air velocity, the condensation level, amount of condensed water, output power, and efficiency. It was found that increasing the chimney inlet air temperature is an efficient way to increase chimney inlet air velocity and wind turbine output power. The operating conditions, such as air temperature and air relative humidity, have significant influence on the condensation level. For water generation, chimney height is the most decisive factor, the mass flow rate of condensed water decreases with increasing wind turbine pressure drop. To achieve the optimum peak output power by wind turbine, we should set the pressure drop factor as about 0.7. In addition, increasing chimney height is also an efficient way to improve the SCPP efficiency. Under ideal conditions, the system total efficiency of a SCPP with a height of 3000 m can be up to nearly 7%.

Atmospheric cooling tower with reduced plume

International Nuclear Information System (INIS)

Gautier, D.M.; Lagoutte, A.

1985-01-01

The cooling tower, usable in thermal-electric power plants, has a vertical chimney having a central water tower fed with water to be cooled, a pipe network distributing water coming from the water tower and dispersing it in flows streaming down on a packing, and a basin to receive the water cooled by contact with an air flow passing through apertures at the lower part of the chimney and flowing up through the chimney. The cooling tower has inlet air pipes for the said apertures to a zone of the chimney situated beyond the streaming zone, the said pipes being arranged such their surface is swept by water to be cooled [fr

Novel concept for producing energy integrating a solar collector with a man made mountain hollow

International Nuclear Information System (INIS)

Zhou Xinping; Yang Jiakuan; Wang Jinbo; Xiao Bo

2009-01-01

The concept of the solar chimney thermal power technology was proven with the successful operation of the Manzanares prototype built in the 1980s. However, all previous attempts at producing energy from a commercial solar chimney thermal power plant on a large scale have failed because of bad engineering and safety. A novel concept for producing energy by integrating a solar collector with a mountain hollow is presented and described. Solar energy is collected in the collector and heats the ground, which is used to store heat energy and heat the indoor air. Then, the hot air is forced by the pressure difference between it and the ambient air to move along the tilted segment and up the vertical segment of the 'chimney', driving the turbine generators to generate electricity. The mountain hollow, formed by excavation in a large-elevation mountain, can avoid the safety issues of erecting a gigantic concrete chimney, which is needed for commercial solar chimney thermal power plants. Furthermore, it can also save a great amount of construction materials for constructing a robust chimney structure and reduce the energy cost to a level less than that of a clean coal power plant, providing a good solution to the reclamation and utilization of undeveloped mountains, especially in mountainous countries

Novel concept for producing energy integrating a solar collector with a man made mountain hollow

Energy Technology Data Exchange (ETDEWEB)

Zhou Xinping [School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei 430074 (China)], E-mail: zhxpmark@hotmail.com; Yang Jiakuan; Wang Jinbo; Xiao Bo [School of Environmental Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road Wuhan, Hubei 430074 (China)

2009-03-15

The concept of the solar chimney thermal power technology was proven with the successful operation of the Manzanares prototype built in the 1980s. However, all previous attempts at producing energy from a commercial solar chimney thermal power plant on a large scale have failed because of bad engineering and safety. A novel concept for producing energy by integrating a solar collector with a mountain hollow is presented and described. Solar energy is collected in the collector and heats the ground, which is used to store heat energy and heat the indoor air. Then, the hot air is forced by the pressure difference between it and the ambient air to move along the tilted segment and up the vertical segment of the 'chimney', driving the turbine generators to generate electricity. The mountain hollow, formed by excavation in a large-elevation mountain, can avoid the safety issues of erecting a gigantic concrete chimney, which is needed for commercial solar chimney thermal power plants. Furthermore, it can also save a great amount of construction materials for constructing a robust chimney structure and reduce the energy cost to a level less than that of a clean coal power plant, providing a good solution to the reclamation and utilization of undeveloped mountains, especially in mountainous countries.

Novel concept for producing energy integrating a solar collector with a man made mountain hollow

Energy Technology Data Exchange (ETDEWEB)

Zhou, Xinping [School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei 430074 (China); Yang, Jiakuan; Wang, Jinbo; Xiao, Bo [School of Environmental Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road Wuhan, Hubei 430074 (China)

2009-03-15

The concept of the solar chimney thermal power technology was proven with the successful operation of the Manzanares prototype built in the 1980s. However, all previous attempts at producing energy from a commercial solar chimney thermal power plant on a large scale have failed because of bad engineering and safety. A novel concept for producing energy by integrating a solar collector with a mountain hollow is presented and described. Solar energy is collected in the collector and heats the ground, which is used to store heat energy and heat the indoor air. Then, the hot air is forced by the pressure difference between it and the ambient air to move along the tilted segment and up the vertical segment of the 'chimney', driving the turbine generators to generate electricity. The mountain hollow, formed by excavation in a large-elevation mountain, can avoid the safety issues of erecting a gigantic concrete chimney, which is needed for commercial solar chimney thermal power plants. Furthermore, it can also save a great amount of construction materials for constructing a robust chimney structure and reduce the energy cost to a level less than that of a clean coal power plant, providing a good solution to the reclamation and utilization of undeveloped mountains, especially in mountainous countries. (author)

Abundance and Distribution of Diagnostic Carbon Fixation Genes in a Deep-Sea Hydrothermal Gradient Ecosystem

Science.gov (United States)

Blumenfeld, H. N.; Kelley, D. S.; Girguis, P. R.; Schrenk, M. O.

2010-12-01

The walls of deep-sea hydrothermal vent chimneys sustain steep thermal and chemical gradients resulting from the mixing of hot (350°C+) hydrothermal fluids with cold, oxygenated seawater. The chemical disequilibrium generated from this process has the potential to drive numerous chemolithoautotrophic metabolisms, many of which have been demonstrated to be operative in microbial pure cultures. In addition to the well-known Calvin Cycle, at least five additional pathways have been discovered including the Reverse Tricarboxylic Acid Cycle (rTCA), the Reductive Acetyl-CoA pathway, and the 3-hydroxyproprionate pathway. Most of the newly discovered pathways have been found in thermophilic and hyperthermophilic Bacteria and Archaea, which are the well represented in microbial diversity studies of hydrothermal chimney walls. However, to date, little is known about the environmental controls that impact various carbon fixation pathways. The overlap of limited microbial diversity with distinct habitat conditions in hydrothermal chimney walls provides an ideal setting to explore these relationships. Hydrothermal chimney walls from multiple structures recovered from the Juan de Fuca Ridge in the northeastern Pacific were sub-sampled and analyzed using PCR-based assays. Earlier work showed elevated microbial abundances in the outer portions of mature chimney walls, with varying ratios of Archaea to Bacteria from the outer to inner portions of the chimneys. Common phylotypes identified in these regions included Epsilonproteobacteria, Gammaproteobacteria, and Desulfurococcales. Total genomic DNA was extracted from mineralogically distinct niches within these structures and queried for genes coding key regulatory enzymes for each of the well studied carbon fixation pathways. Preliminary results show the occurrence of genes representing rTCA cycle (aclB) and methyl coenzyme A reductase (mcrA) - a proxy for the Reductive Acetyl-CoA Pathway within interior portion of mature

Evaluation of nutrient and energy sources of the deepest known serpentinite-hosted ecosystem using stable carbon, nitrogen, and sulfur isotopes.

Science.gov (United States)

Onishi, Yuji; Yamanaka, Toshiro; Okumura, Tomoyo; Kawagucci, Shinsuke; Watanabe, Hiromi Kayama; Ohara, Yasuhiko

2018-01-01

The Shinkai Seep Field (SSF) in the southern Mariana forearc discovered in 2010 is the deepest (~5,700 m in depth) known serpentinite-hosted ecosystem dominated by a vesicomyid clam, Calyptogena (Abyssogena) mariana. The pioneering study presumed that the animal communities are primary sustained by reducing fluid originated from the serpentinization of mantle peridotite. For understanding the nutrient and energy sources for the SSF community, this study conducted four expeditions to the SSF and collected additional animal samples such as polychaetes and crustaceans as well as sediments, fragments of chimneys developing on fissures of serpentinized peridotite, seeping fluid on the chimneys, and pore water within the chimneys. Geochemical analyses of seeping fluids on the chimneys and pore water of the chimneys revealed significantly high pH (~10) that suggest subseafloor serpentinization controlling fluid chemistry. Stable isotope systematics (carbon, nitrogen, and sulfur) among animals, inorganic molecules, and environmental organic matter suggest that the SSF animal community mostly relies on the chemosynthetic production while some organisms appear to partly benefit from photosynthetic production despite the great depth of SSF.

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

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.)

The hillsides would allow to produce electric power from renewable source

International Nuclear Information System (INIS)

Laby, F.

2006-09-01

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.)

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.)

Staying safe at home

Science.gov (United States)

... the chimney or flu, which can cause chimney fires. Use a glass or metal screen in front of your fireplace to keep sparks from popping out and starting a fire. Make sure the door latch on the wood ...

Adoption of a fiber reinforced plastics (FRP) inner cylinder for the chimney stack at the Wakayama power plant; Wakayama hatsudensho entotsu eno FRP sei naito no saiyo ni tsuite

Energy Technology Data Exchange (ETDEWEB)

Hirakawa, M. [Kansai Electric Power Co. Inc., Osaka (Japan)

2000-05-10

The chimney stack at the Wakayama power plant is planned to adopt a fiber reinforced plastics (FRP) inner cylinder having greater cost reduction effect than a steel made inner cylinder. The present study has performed different experiments on FRP under the gas emitting condition at the Wakayama power plant, and discussed structural plans based on the result therefrom. The Wakayama power plant has the waste gas raised in temperature because of difference in the power generation system. Therefore, physical constant verification tests and heat resistance tests were performed on FRP to verify its applicability. Structural discussions to pursue economy were given on the 'joints' and 'suspension points' (supporting points to suspend the FRP inner cylinder) being the major FRP structures based on the actual record at the Nanko power plant. The tests have placed focus on the 'heat resistance', and different experiments were carried out upon selecting two kinds of novolak-based vinyl ester resins. As a result, applicability of the FRP made inner cylinder to high waste gas temperatures was verified, and so were various property values to be used for designing the cylinder. Structural design was performed by applying design safety factor to the derived property values, and the basic structural plan was established for the FRP inner cylinder. (NEDO)

Chemistry of a serpentinization-controlled hydrothermal system at the Lost City hydrothermal vent field

Science.gov (United States)

Ludwig, K. A.; Kelley, D. S.; Butterfield, D. A.; Nelson, B. K.; Karson, J. A.

2003-12-01

The Lost City Hydrothermal Field (LCHF), at 30° N near the Mid-Atlantic Ridge, is an off-axis, low temperature, high-pH, ultramafic-hosted vent system. Within the field, carbonate chimneys tower up to 60 m above the seafloor, making them the tallest vent structures known. The chemistry of the vent structures and fluids at the LCHF is controlled by reactions between seawater and ultramafic rocks beneath the Atlantis massif. Mixing of warm alkaline vent fluids with seawater causes precipitation of calcium carbonate and growth of the edifaces, which range from tall, graceful pinnacles to fragile flanges and colloform deposits. Geochemical and petrological analyses of the carbonate rocks reveal distinct differences between the active and extinct structures. Actively venting chimneys and flanges are extremely porous, friable formations composed predominantly of aragonite and brucite. These structures provide important niches for well-developed microbial communities that thrive on and within the chimney walls. Some of the active chimneys may also contain the mineral ikaite, an unstable, hydrated form of calcium carbonate. TIMS and ICP-MS analyses of the carbonate chimneys show that the most active chimneys have low Sr isotope values and that they are low in trace metals (e.g., Mn, Ti, Pb). Active structures emit high-pH, low-Mg fluids at 40-90° C. The fluids also have low Sr values, indicating circulation of hydrothermal solutions through the serpentinite bedrock beneath the field. In contrast to the active structures, extinct chimneys are less porous, are well lithified, and they are composed predominantly of calcite that yields Sr isotopes near seawater values. Prolonged lower temperature seawater-hydrothermal fluid interaction within the chimneys results in the conversion of aragonite to calcite and in the enrichment of some trace metals (e.g., Mn, Ti, Co, Zn). It also promotes the incorporation of foraminifera within the outer, cemented walls of the carbonate

Passive filtration of air egressing from nuclear containment

Energy Technology Data Exchange (ETDEWEB)

Malloy, III, John D

2017-09-26

A nuclear reactor includes a reactor core comprising fissile material disposed in a reactor pressure vessel. A radiological containment contains the nuclear reactor. A containment compartment contains the radiological containment. A heat sink includes a chimney configured to develop an upward-flowing draft in response to heated fluid flowing into a lower portion of the chimney. A fluid conduit is arranged to receive fluid from the containment compartment and to discharge into the chimney. A filter may be provided, with the fluid conduit including a first fluid conduit arranged to receive fluid from the containment compartment and to discharge into an inlet of the filter, and a second fluid conduit arranged to receive fluid from an outlet of the filter and to discharge into the chimney. As the draft is developed passively, there is no need for a blower or pump configured to move fluid through the fluid conduit.

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.

Simulating Electrochemistry of Hydrothermal Vents on Enceladus and Other Ocean Worlds

Science.gov (United States)

Barge, L. M.; Krause, F. C.; Jones, J. P.; Billings, K.; Sobron, P.

2017-12-01

Gradients generated in hydrothermal systems provide a significant source of free energy for chemosynthetic life, and may play a role in present-day habitability on ocean worlds such as Enceladus that are thought to host hydrothermal activity. Hydrothermal vents are similar in some ways to typical fuel cell devices: redox/pH gradients between seawater and hydrothermal fluid are analogous to the oxidant and fuel reservoirs; conductive natural mineral deposits are analogous to electrodes; and, in hydrothermal chimneys, the porous chimney wall can function as a separator or ion-exchange membrane. Electrochemistry, founded on quantitative study of redox and other chemical disequilibria as well as the chemistry of interfaces, is uniquely suited to studying these systems. We have performed electrochemical studies to better understand the catalytic potential of seafloor minerals and vent chimneys, using samples from a black smoker vent chimney as an initial demonstration. Fuel cell experiments with electrodes made from black smoker chimney material accurately simulated the redox reactions that occur in a geological setting with this particular catalyst. Similar methods with other geo-catalysts (natural or synthetic) could be utilized to test which redox reactions or metabolisms could be driven in other hydrothermal systems, including putative vent systems on other worlds.

Characterizing Particulate Matter Exfiltration Estimates for Alternative Cookstoves in a Village-Like Household in Rural Nepal

Science.gov (United States)

Soneja, Sutyajeet I.; Tielsch, James M.; Khatry, Subarna K.; Zaitchik, Benjamin; Curriero, Frank C.; Breysse, Patrick N.

2017-11-01

Alternative stoves are an intervention option to reduce household air pollution. The amount of air pollution exiting homes when alternative stoves are utilized is not known. In this paper, particulate matter exfiltration estimates are presented for four types of alternative stoves within a village-like home, which was built to reflect the use of local materials and common size, in rural Nepal. Four alternative stoves with chimneys were examined, which included an alternative mud brick stove, original Envirofit G3355 model, manufacture altered Envirofit G3355, and locally altered Envirofit G3355. Multiple linear regression was utilized to determine estimates of PM2.5 exfiltration. Overall exfiltration fraction average (converted to a percent) for the four stoves were: alternative mud brick stove with chimney 56%, original Envirofit G3355 model with chimney 87%, manufacture altered Envirofit G3355 model with chimney 69%, and locally altered Envirofit G3355 model with chimney 69%. Alternative cookstoves resulted in higher overall average exfiltration due to direct and indirect ventilation relative to traditional, mud-based stoves. This contrast emphasizes the need for an improved understanding of the climate and health implications that are believed to come from implementing alternative stoves on a large scale and the resultant shift of exposure burden from indoors to outdoors.

Air pollution hazards in brick kilns

Energy Technology Data Exchange (ETDEWEB)

Aslam, M; Srivastava, R S; Minocha, A K; Gupta, R G [Central Building Research Institute, Roorkee (India)

1994-02-01

Three types of brick kiln - Bull's trench kiln of movable chimney type, Bull's trench kiln of fixed chimney type, and high draught kiln of normal capacity (25,000-30,000 bricks/day) fed manually with slack coal and other local fuels - were investigated for stack emissions. Dust and hydrocarbons were identified as chief pollutants. Particle size analysis of dust emitted from movable chimney kiln and its impact on ambient air quality were also studied. Based on these studies, recommendations have been drawn on their comparative pollution hazard and need for optimization of operational parameters to improve their thermal performance and reduce pollution emission. 15 refs., 4 tabs.

Density wave oscillations of a boiling natural circulation loop induced by flashing

Energy Technology Data Exchange (ETDEWEB)

Furuya, Masahiro; Inada, Fumio; Yasuo, Akira [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1995-09-01

Experiments are conducted to investigate two-phase flow instabilities in a boiling natural circulation loop with a chimney due to flashing in the chimney at lower pressure. The test facility used in this experiment is designed to have non-dimensional values which are nearly equal to those of natural circulation BWR. Stability maps in reference to the heat flux, the inlet subcooling, the system pressure are presented. This instability is suggested to be density wave oscillations due to flashing in the chimney, and the differences from other phenomena such as flow pattern oscillations and geysering phenomena are discussed by investigating the dynamic characteristics, the oscillation period, and the transient flow pattern.

Formation of black and white smokers in the North Fiji Basin: Sulfur and lead isotope constraints

Science.gov (United States)

Kim, J.; Lee, I.; Lee, K.; Yoo, C.; Ko, Y.

2004-12-01

The hydrothermal chimneys were recovered from 16o50¡_S triple junction area in the North Fiji Basin. The chimney samples are divided into three groups according to their mineralogy and metal contents; 1) Black smoker, 2) White smoker, 3) Transitional type. Black smoker chimneys are mainly composed of chalcopyrite and pyrite, and are enriched in high temperature elements such as Cu, Co, Mo, and Se. White smoker chimneys consist of sphalerite and marcasite with trace of pyrite and chalcopyrite, and are enriched in low temperature elements (Zn, Cd, Pb, As, and Ga). Transitional chimneys show intermediate characteristics in mineralogy and composition between black and white smokers. Basaltic rocks sampled from the triple junction show wide variation in geochemistry. Trace elements composition of basaltic rocks indicates that the magma genesis in the triple junction area was affected by mixing between N-MORB and E-MORB sources. The sulfur and lead isotope compositions of hydrothermal chimneys show distinct differences between the black and white smokers. Black smokers are depleted in 34S (Øä34S = +0.4 to +4.8) and are low in lead isotope composition (206Pb/204Pb = 18.082 to 18.132; 207Pb/204Pb = 15.440 to 15.481; 208Pb/204Pb = 37.764 to 37.916) compared to white smoker and transitional chimneys (Øä34S = +2.4 to +5.6; 206Pb/204Pb = 18.122 to 18.193; 207Pb/204Pb = 15.475 to 15.554; 208Pb/204Pb = 37.882 to 38.150). The heavier sulfur isotopic fractionation in white smoker can be explained by boiling of hydrothermal fluids and mixing with ambient seawater. The lead isotope compositions of the hydrothermal chimneys indicate that the metal in black and white smokers come from hydrothermal reaction with N-MORB and E-MORB, respectively. Regarding both black and white smoker are located in the same site, the condition of phase separation of hydrothermal fluid that formed white smokers might result from P-T condition of high temperature reaction zone below the hydrothermal

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....

Experimental study in natural convection | Ousmane | Global Journal ...

African Journals Online (AJOL)

Experimental measurements has been made to determine the temperature of the absorber and the fluid in the collector, it is shown that at the entrance of the chimney, ... Thus, the results of simulations with the computer code COMSOL 5.1 has confirmed temperature values measured at the chimney entrance and after this, ...

Subsidence caused by an underground nuclear explosion

Energy Technology Data Exchange (ETDEWEB)

Hakala, W W [Environmental Research Corp., Alexandria, VA (United States)

1970-05-15

An underground nuclear detonation creates a cavity, which may be followed by the formation of a rubble chimney and possibly by a surface subsidence crater. A knowledge of the mechanisms of surface and subsurface subsidence is valuable not only because of the potential engineering uses of the chimneys and craters that may form, but also for the prevention of surface damage. Some of the parameters that are of interest in the subsidence phenomenon are the height and volume of the chimney, the porosity of the chimney, the crater size (depth and radius) and shape, and the time required after detonation for formation of the chimney or crater. The influence of the properties of the subsidence medium on the geometry of the subsidence crater must be considered. The conditions under which partial or complete subsidence is prevented must also be studied. The applicability of the relations that have been developed for the flow of bulk solids for relatively small masses and low pressures to the subsidence problem associated with nuclear explosions is examined. Rational modifications are made to describe the subsidence problem. Sensitivity of the subsidence parameters to material properties and the prevailing geometry is shown. Comparison with observed results at the Nevada Test Site is made and the variations encountered are found to be within reasonable limits. The chimney size and subsidence crater dimensions are found to be a function of the bulking characteristics of the medium, the strength parameters, the dimensions of the subsurface cavity, and the depth of the cavity. The great influence of the strength parameters on the collapse times is shown. For a given medium, the prevention of subsidence is dependent on the cavity size. (author)

Exceptional discovery of a shallow-water hydrothermal site in the SW area of Basiluzzo islet (Aeolian archipelago, South Tyrrhenian Sea: An environment to preserve.

Directory of Open Access Journals (Sweden)

Valentina Esposito

Full Text Available The geological, biological and geochemical features of a particular field of hydrothermal vents, discovered in the Panarea Volcanic Complex during a research survey carried out in 2015, are described for the first time. The site, located at 70-80 m depth off the South-western coast of the islet of Basiluzzo, was named Smoking Land for the presence of a large number of wide and high active chimneys and was characterized in terms of dissolved benthic fluxes, associated macrofauna and megafauna communities and preliminary mineralogy and geochemistry of chimney structures. On the whole field, a total of 39 chimneys, different in size and shape, were closely observed and described; 14 of them showed emission of low temperature hydrothermal fluids of marine origin characterized by acidified chemical conditions. The CTD and benthic chamber measurements highlighted that the Smoking Land is able to form a sea water bottom layer characterized by variable acidity and high DIC and trace elements concentrations; these characteristics weaken moving away from the chimney mouths. The SEM-EDS analysis of the collected solid samples revealed a chimney structure principally composed by amorphous and low crystalline Fe-oxyhydroxides of hydrothermal origins. The ROV explorations revealed a wide coverage of red algae (Peyssonnelia spp. colonized by the green algae Flabiella petiolata and by suspension feeders, mainly sponges, but also bryozoans, and tubicolous polychaetes. Although novent-exclusive species were identified, the benthic communities found in association to the chimneys included more taxa than those observed in the surrounding no-vent rocky areas. These first findings evidence a submarine dynamic habitat where geological, chemical and biological processes are intimately connected, making the Smoking Land an important site in terms of marine heritage that should be safeguarded and protected.

Exceptional discovery of a shallow-water hydrothermal site in the SW area of Basiluzzo islet (Aeolian archipelago, South Tyrrhenian Sea): An environment to preserve

Science.gov (United States)

Andaloro, Franco; Canese, Simonepietro; Bo, Marzia; Di Bella, Marcella; Italiano, Francesco; Sabatino, Giuseppe; Battaglia, Pietro; Consoli, Pierpaolo; Giordano, Patrizia; Spagnoli, Federico; La Cono, Violetta; Yakimov, Michail M.; Scotti, Gianfranco; Romeo, Teresa

2018-01-01

The geological, biological and geochemical features of a particular field of hydrothermal vents, discovered in the Panarea Volcanic Complex during a research survey carried out in 2015, are described for the first time. The site, located at 70–80 m depth off the South-western coast of the islet of Basiluzzo, was named Smoking Land for the presence of a large number of wide and high active chimneys and was characterized in terms of dissolved benthic fluxes, associated macrofauna and megafauna communities and preliminary mineralogy and geochemistry of chimney structures. On the whole field, a total of 39 chimneys, different in size and shape, were closely observed and described; 14 of them showed emission of low temperature hydrothermal fluids of marine origin characterized by acidified chemical conditions. The CTD and benthic chamber measurements highlighted that the Smoking Land is able to form a sea water bottom layer characterized by variable acidity and high DIC and trace elements concentrations; these characteristics weaken moving away from the chimney mouths. The SEM-EDS analysis of the collected solid samples revealed a chimney structure principally composed by amorphous and low crystalline Fe-oxyhydroxides of hydrothermal origins. The ROV explorations revealed a wide coverage of red algae (Peyssonnelia spp.) colonized by the green algae Flabiella petiolata and by suspension feeders, mainly sponges, but also bryozoans, and tubicolous polychaetes. Although novent-exclusive species were identified, the benthic communities found in association to the chimneys included more taxa than those observed in the surrounding no-vent rocky areas. These first findings evidence a submarine dynamic habitat where geological, chemical and biological processes are intimately connected, making the Smoking Land an important site in terms of marine heritage that should be safeguarded and protected. PMID:29300784

Carcinogenic agents present in the atmosphere and incidence of primary lung tumors in mice

Energy Technology Data Exchange (ETDEWEB)

Campbell, J A

1939-01-01

Exposure of mice to suspended benzene extracts of exhaust pipe soot from engine burning heavy oil for once/hr, 6 hr/day, for a lifetime, produced a slight increase in lung tumors whereas chimney soot had no effect. Conversely, chimney soot extract painted on skin was judged carcinogenic, whereas exhaust soot did not produce cancer.

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)

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�

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.

Parametric study of boiling heat transfer in porous media

International Nuclear Information System (INIS)

Shi, B.; Jones, B.G.; Pan, C.

1996-01-01

Detailed numerical modeling and parametric variation studies were conducted on boiling heat transfer processes in porous deposits with emphasis on applications associated with light water nuclear power reactor systems. The processes of boiling heat transfer in the porous corrosion deposits typically involve phase changes in finite volumetric regions in the porous media. The study examined such processes in two porous media configurations, without chimneys (homogeneous porous structures) and with chimneys (heterogeneous porous structures). A 1-D model and a 2-D model were developed to simulate two-phase flows with phase changes, without dry-out, inside the porous media for both structural configurations. For closure of the governing equations, an empirical correlation of the evaporation rate for phase changes inside the porous media was introduced. In addition, numerical algorithms were developed to solve the coupled nonlinear equations of mass, momentum, energy, capillary pressure, and evaporation rate. The distributions of temperature, thermodynamic saturation, liquid pressure, vapor pressure, liquid velocity, and vapor velocity were predicted. Furthermore, the effects of heat flux, system pressure, porosity, particle diameter, chimney population density, chimney radius, and crud thickness on the all superheat, critical heat flux, and minimum saturation were examined. The predictions were found to be in good agreement with the available experimental results

Method of extracting shale with hot gases

Energy Technology Data Exchange (ETDEWEB)

Hervier, M

1874-12-05

The raw rock is treated in a furnace composed of a series of compartments arranged in a circle around a hearth and communicating with one another by means of a chimney. The chargers receiving the rock communicate at the top directly with little cells in which terminate the chimneys for the circulation. These chambers are accessible to the combustion gases from the central hearth by means of flues. A damper, operated from outside, closes the chimney or flue at will. A grill is installed at the lower part of each chamber and supports the bituminous rocks to be treated, the rock being charged in at the top of the chamber. Each chamber is set on a reservoir of cast iron, the reservoir being slightly inclined toward the outside and receiving the liquid products separated from the rock.

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

Gas quality analysis and evaluation program for project Gasbuggy

Energy Technology Data Exchange (ETDEWEB)

Smith, C F [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-01

Experimental results of the gas quality analysis program for Project Gasbuggy through August 1969 are presented graphically, addressing the questions raised by the preshot program goals. The chemical composition and the concentrations of tritium, krypton-85, carbon-14 and argon-37, 39 are presented as a function of time and gas production from the nuclear chimney. Chemically, the presence of CO{sub 2}, CO and H{sub 2} served to dilute the formation gas and caused reactions which significantly altered the gas composition at early times. The radionuclide content of the chimney gas at reentry was some 800 pCi/cm{sup 3} of which about 80% was CH{sub 3}T. Lesser quantities of tritium were observed as HT, C{sub 2}H{sub 5}T and C{sub 3}H{sub 7}T. The other major contaminant was Kr{sup 85} which was present at about one-fifth the level of CH{sub 3}T. Small quantities of carbon-14 and argon-39 were also identified. The only other radionuclides identified in the gas were relatively short-lived rare gases. During the production testing, about two and one-half chimney volumes of gas at formation pressure were removed. This removal, accompanied by dilution, has reduced the radionuclide concentrations to about 7% of their levels at reentry. The production characteristics of the Gasbuggy environment prevented an adequate test of the effectiveness of chimney flushing. However, the rapid drawdown concept is supported by the available data as an effective means of reducing contaminant levels. The changes in composition during production or testing are seen to be consistent with a model involving a non-uniform gas influx rate and flow distribution over the chimney region. Mixing times are estimated to be on the order of a few days, so that increasing concentrations following a sudden gas influx can be explained. (author)

Behavior of radionuclides in nuclear gas stimulation applications

Energy Technology Data Exchange (ETDEWEB)

Smith, Jr, C F [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-01

The Gasbuggy experiment has presented a unique opportunity to investigate the behavior of radionuclides over an extended period of time in a somewhat unusual environment. In addition to the obvious practical utility of this investigation for Plowshare applications, the information gained has value of a purely scientific nature. Both aspects of the Gas Quality program for Gasbuggy are discussed in this presentation. The study of Gasbuggy results is divided into two distinct periods, according to the field operations. During the initial six months following detonation, the chimney reentry well was shut-in, and the nuclear chimney served as a chemical and radiochemical reaction vessel. A detailed examination of the concentrations and specific activities of tritium and C{sup 14} is presented as a function of the changing chemical composition of the chimney gas and as a function of time. The effects of radiochemical exchange reactions, together with the tritium isotope effect, are demonstrated. Following this shut-in period, a series of production and flushing tests was conducted. During these experiments, the chimney gas composition was seen to change about as would be expected due to dilution of the chimney gas with formation gas. An examination of radionuclide concentrations and specific activities during the production tests demonstrated the relative unimportance of isotopic exchange and chemical reactions during this period, as compared to the early shut-in periods. Within the limitations of the Gasbuggy experience a generalized model of the behavior of tritium and C{sup 14} can be deduced. The discussion involves estimation of initial distribution of activities, the effects of chemical reactions and isotopic exchange on this distribution, and the importance of the environment in determining the level of radioactivity contamination to be expected. (author)

Engineering effects of underground nuclear explosions

International Nuclear Information System (INIS)

Boardman, Charles R.

1970-01-01

Useful effects of contained underground nuclear explosions are discussed in light of today's most promising potential applications. Relevant data obtained through exploration of explosion environments of nine U.S. tests in competent rock are summarized and presented as a practical basis for estimating magnitudes of effects. Effects discussed include chimney configuration, permeability, and volume as well as rubble particle size distributions and extents of permeability change in the chimney wall rock. Explosion mediums include shale, granite, dolomite, and salt. (author)

Engineering effects of underground nuclear explosions

Energy Technology Data Exchange (ETDEWEB)

Boardman, Charles R [CER Geonuclear Corporation, Las Vegas, NV (United States)

1970-05-01

Useful effects of contained underground nuclear explosions are discussed in light of today's most promising potential applications. Relevant data obtained through exploration of explosion environments of nine U.S. tests in competent rock are summarized and presented as a practical basis for estimating magnitudes of effects. Effects discussed include chimney configuration, permeability, and volume as well as rubble particle size distributions and extents of permeability change in the chimney wall rock. Explosion mediums include shale, granite, dolomite, and salt. (author)

A system for the discharge of gas bubbles from the coolant flow of a nuclear reactor cooled by forced circulation

International Nuclear Information System (INIS)

Markfort, D.; Kaiser, A.; Dohmen, A.

1975-01-01

In a reactor cooled by forced circulation the gas bubbles carried along with the coolant flow are separated before entering the reactor core or forced away into the external zones. For this purpose the coolant is radially guided into a plenum below the core and deflected to a tangential direction by means of flow guide elements. The flow runs spirally downwards. On the bubbles, during their dwell time in this channel, the buoyant force and a force towards the axis of symmetry of the tank are exerted. The major part of the coolant is directed into a radial direction by means of a guiding apparatus in the lower section of the channel and guided through a chimney in the plenum to the center of the reactor core. This inner chimney is enclosed by an outer chimney for the core edge zones through which coolant with a small share of bubbles is taken away. (RW) [de

Feasibility of utilising solar-induced ventilation in Malaysia

International Nuclear Information System (INIS)

Ong, K.S.; Chow, C.C.

2006-01-01

The feasibility of applying solar-induced ventilation in a typical Malaysian house measuring 3 m high x wide x 5 m deep was considered based on experimental results obtained from a laboratory-scale model. A wall-type solar chimney was considered. The design of the solar chimney incorporated providing a glass panel alongside a vertical wall of a building. Openings at the top and bottom of the wall allowed fresh air to be introduced into the building. Simulations obtained from a simple theoretical model showed that the solar chimney was able to induce air flow rates of between 640 to 1040 m3 h-1 with a 0.3 m air gap. These ventilation rates are found to be in compliance with codes specified by ASHRAE and the Uniform Building By-laws. Full scale studies would need to be conducted in order to evaluate its effectiveness especially the flow pattern in the room

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...

A Determination of Eligibility to the National Register of Historic Places for Select Historic Properties Along the Souris River in North Dakota

Science.gov (United States)

1989-08-01

Company Historic District," 1985. "Historic Resources of Hardin, Montana," :984. "Silver Bow Brewery Malt House," 1982. "Silver Bow County Poor Farm...34i QQL-- Q ..i FEATURE TYPE CULTURAL MATERIAL ’iii Site Type -0,- Cm Scatter , , Bone 0 Chimney %.Z Ceramics tA Context .Q, Depression 1 Charcoal i...Sec , QQQ i, QQ . Q, ,LTL, L- Twp R ,.. , Sec ,., QQO 1- QQ’ L- Q’ ’ FEATURE TYPE CULTURAL MATERIAL &. Site Type m, Cm Scatter ,.Z, Bone Chimney

Estimates of potential radionuclide migration at the Bullion site

International Nuclear Information System (INIS)

Brikowski, T.H.

1992-04-01

The Bullion site in Area 20 of the Nevada Test Site has been selected for an intensive study of the hydrologic consequences of underground testing, including subsequent radionuclide migration. The bulk of the chimney and cavity lie in zeolitized tuffs of low hydraulic conductivity, while the base of the cavity may extend downward into more conductive rhyolite flows. A mathematical analog to the Bullion setting is used here to estimate expected radionuclide migration rates and concentrations. Because of a lack of hydrologic data at the site, two contrasting scenarios are considered. The first is downward-transport, in which downward hydraulic gradients flush chimney contents into the conductive underlying units, enhancing migration. The other is upward-transport, in which upward gradients tend to drive chimney contents into the low-conductivity zeolitized tuffs, discouraging migration. In the downward-transport scenario, radionuclide travel times and concentrations are predicted to be similar to those encountered at Cheshire, requiring approximately 10 years to reach a proposed well 300 m downgradient. The upward transport scenario yields predicted travel times on the order of 2,000 years to the downgradient well. The most likely scenario is a combination of these results, with vertical movement playing a limited role. Radionuclides injected directly into the rhyolites should migrate laterally very quickly, with travel times as in the downward-transport scenario. Those in the zeolitized tuff-walled portion of the chimney should migrate extremely slowly, as in the upward-transport scenario

Inversion of Multi-Station Schumann Resonance Background Records for Global Lightning Activity in Absolute Units

Science.gov (United States)

Williams, E. R.; Mushtak, V. C.; Guha, A.; Boldi, R. A.; Bor, J.; Nagy, T.; Satori, G.; Sinha, A. K.; Rawat, R.; Hobara, Y.; Sato, M.; Takahashi, Y.; Price, C. G.; Neska, M.; Alexander, K.; Yampolski, Y.; Moore, R. C.; Mitchell, M. F.; Fraser-Smith, A. C.

2014-12-01

Every lightning flash contributes energy to the TEM mode of the natural global waveguide that contains the Earth's Schumann resonances. The modest attenuation at ELF (0.1 dB/Mm) allows for the continuous monitoring of the global lightning with a small number of receiving stations worldwide. In this study, nine ELF receiving sites (in Antarctica (3 sites), Hungary, India, Japan, Poland, Spitsbergen and USA) are used to provide power spectra at 12-minute intervals in two absolutely calibrated magnetic fields and occasionally, one electric field, with up to five resonance modes each. The observables are the extracted modal parameters (peak intensity, peak frequency and Q-factor) for each spectrum. The unknown quantities are the geographical locations of three continental lightning 'chimneys' and their lightning source strengths in absolute units (C2 km2/sec). The unknowns are calculated from the observables by the iterative inversion of an evolving 'sensitivity matrix' whose elements are the partial derivatives of each observable for all receiving sites with respect to each unknown quantity. The propagation model includes the important day-night asymmetry of the natural waveguide. To overcome the problem of multiple minima (common in inversion problems of this kind), location information from the World Wide Lightning Location Network has been used to make initial guess solutions based on centroids of stroke locations in each chimney. Results for five consecutive days in 2009 (Jan 7-11) show UT variations with the African chimney dominating on four of five days, and America dominating on the fifth day. The amplitude variations in absolute source strength exceed that of the 'Carnegie curve' of the DC global circuit by roughly twofold. Day-to-day variations in chimney source strength are of the order of tens of percent. Examination of forward calculations performed with the global inversion solution often show good agreement with the observed diurnal variations at

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

International Nuclear Information System (INIS)

Khan, T.; Chaudhry, I.A.; Rehman, A.

2014-01-01

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)

Will nuclear blasts reverberate in the CPI chemical process industry

Energy Technology Data Exchange (ETDEWEB)

Chopey, N P

1968-03-11

Fully contained nuclear explosions result in a rubble- filled chimney having fractures up to 4 times the radius of the cavity itself. For natural gas stimulation, Project Gasbuggy boosters hope the explosion-produced network of fractures will provide a more-effective drainage of the gas reservoir. An expanded well bore should allow higher sustained rates of production, and the void space should afford an effective storage area for a high delivery rate over a short period of time. Nuclear stimulation should pay for itself best in deep, thick, low-permeability gas fields such as those located in the Rocky Mt. region. Copper producers foresee the use of nuclear blasts to create a chimney of broken low-grade ore that would be economically unworkable by ordinary means. For shale oil production, the blast would form a chimney of shale chunks that would likewise be treated in situ, by a new technique in which the material would be distilled or decomposed by heat. All these possibilites are still at preliminary exploratory stages, and much more work is needed to see if they are practical.

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

International Nuclear Information System (INIS)

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

2016-01-01

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. - Highlights: • Similar composition for emitted particles as those collected on the chimney filters. • Emitted particles dominated by Ca-, Mn and/or Al-containing particles. • Identification of specific particle types emitted by the different process units. - The particles emitted by metallurgy activities are fully described by ATOFMS and SEM-EDX, enabling the identification of specific particle types from the different units of the process.

Effect of isolator plates on telecom shelter

Science.gov (United States)

Drid, M. Mebrouk; Dokkar, Boubekeur; Dokkar, Abdelghani; Settou, Noureddine; Chennouf, Nasreddine

2018-05-01

Passive ventilation systems are being increasingly proposed as an alternate to mechanical ventilation systems. This tendency is due to their potential benefits in terms of operational cost, energy requirement and carbon dioxide emission. In the present work, fresh flow is introduced under external isolator plates in order to reduce indoor temperature of telecom shelter located at neighboring of Ouargla city (south of Algeria). The metallic plates play two roles; the first one is to protect shelter from sun rays and the second is to operate as solar chimney. This chimney creates upward airflow which operates as passive cooling for the microwave relay. During the whole year, Shelter audit energy has been examined using Trnsys 16 software. Then, CFD code (Fluent 6.3) is used to predict thermal performance and fluid flow in two-dimensional computational domain for solar chimneys. The obtained results show that flow increase at shelter inlet causes a marked improvement in shelter cooling. This improvement indicates that shelter can be designed with small conventional air conditioning which leads to significant energy consumption fall. Indeed, with this technique, indoor temperature reduction can reach about 30°K without any electrical energy dispenses.

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Flow characteristics of Korea multi-purpose research reactor

Energy Technology Data Exchange (ETDEWEB)

Heonil Kim; Hee Taek Chae; Byung Jin Jun; Ji Bok Lee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-09-01

The construction of Korea Multi-purpose Research Reactor (KMRR), a 30 MW{sub th} open-tank-in-pool type, is completed. Various thermal-hydraulic experiments have been conducted to verify the design characteristics of the KMRR. This paper describes the commissioning experiments to determine the flow distribution of KMRR core and the flow characteristics inside the chimney which stands on top of the core. The core flow is distributed to within {+-}6% of the average values, which is sufficiently flat in the sense that the design velocity in the fueled region is satisfied. The role of core bypass flow to confine the activated core coolant in the chimney structure is confirmed.

Device for storage of radio-nuclide configurations releasing heat

International Nuclear Information System (INIS)

Schoenfeld, R.; Jeschar, R.; Tenhumberg, M.

1985-01-01

In dry intermediate storage of burnt-up fuel elements and HAN, the storage shafts have cooling air flowing through them in the axial direction. The lids of the storage cells are made into heat exchangers via the outer cooling air circulation. Inside the storage cells, vertical, spatially and functionally separate updraught and downdraught chimneys are situated at the openings of the storage shafts. To force a convection flow of the right direction inside the storage cells, the lid or the storage shafts are inclined in the direction of the downdraught chimney or the storage shafts are provided with flow obstructions favouring one direction. (orig./HP) [de

Strengthening of tower-like structures. Typical cases of weakening and their repair; Verstaerkung turmartiger Bauwerke. Typische Schwaechungen und ihre Behebung

Energy Technology Data Exchange (ETDEWEB)

Noakowski, Piotr; Breddermann, Martin; Harling, Andreas; Rost, Markus; Potratz, Sabine; Leszinski, Holger [FaAA - Failure Analysis Associates Engineering und Forschung im Bauwesen, Duesseldorf (Germany)

2010-01-15

In view of our cramped built-up environment, the further use of existing tower-like structures is of high importance. Many of those structures need strengthening which has different causes: sensitive structural design according to old standards and experiences; distinct aging due to severe operation, lack of maintenance and frequent shut down; insufficient wind bearing capacity for upgrading with platforms and antennas; change of the chimney operation to hot or wet flue gases; some flaws in the original structural solutions. The paper describes several strengthening methods for concrete towers, masonry towers, and concrete masts. The projects regard locations of cell phone masts and industrial chimneys which are not specified here. (orig.)

Evolution of the Mothra Hydrothermal Field, Endeavour Segment of the Juan de Fuca Ridge

Science.gov (United States)

Glickson, D.; Kelley, D. S.; Delaney, J.

2005-12-01

The Mothra Hydrothermal Field (MHF) is a 600 m long, high-temperature hydrothermal field. It is located 2.7 km south of the Main Endeavour Field at the southern end of the central Endeavour Segment. Mothra is the most areally extensive field along the Endeavour Segment, composed of six active sulfide clusters that are 40-200 m apart. Each cluster contains rare black smokers (venting up to 319°C), numerous diffusely venting chimneys, and abundant extinct chimneys and sulfide talus. From north to south, these clusters include Cauldron, Twin Peaks, Faulty Towers, Crab Basin, Cuchalainn, and Stonehenge. As part of the Endeavour Integrated Study Site (ISS), the MHF is a site of intensive interdisciplinary studies focused on linkages among geology, geochemistry, fluid chemistry, seismology, and microbiology. Axial valley geology at MHF is structurally complex, consisting of lightly fissured flows that abut the walls and surround a core of extensively fissured, collapsed terrain. Fissure abundance and distribution indicates that tectonism has been the dominant process controlling growth of the axial graben. Past magmatic activity is shown by the 200 m long chain of collapse basins between Crab Basin and Stonehenge, which may have held at least ~7500 m3 of lava. Assuming a flow thickness of 0.5 m, this amount of lava could cover over half the valley floor during a single volcanic event. At a local scale, MHF clusters vary in size, activity, and underlying geology. They range in size from 400-1600 m2 and consist of isolated chimneys and/or coalesced cockscomb arrays atop ramps of sulfide talus. In the northern part of the field, Cauldron, Twin Peaks, Faulty Towers, and Crab Basin are located near the western valley wall, bounded by basalt talus and a combination of collapsed sheet flows, intermixed lobate and sulfide, disrupted terrain, and isolated pillow ridges. The southern clusters, Cuchalainn and Stonehenge, are associated with collapse basins in the central valley

DESAIN KONSEP TANGKI PENAMPUNG BAHAN BAKAR PASSIVE COMPACT MOLTEN SALT REACTOR

Directory of Open Access Journals (Sweden)

A. Hadiwinata

2015-04-01

Full Text Available Passive Compact Molten Salt Reactor (PCMSR merupakan pengembangan dari reaktor MSR. Desain reaktor PCMSR membutuhkan tempat khusus penampung sementara bahan bakar pada saat terjadi insiden, misalnya kecelakaan yang menyebabkan peningkatan suhu bahan bakar. Tangki penampung bahan bakar tersusun dari 3 bagian yang saling terhubung yaitu bagian penampung cairan bahan bakar, cerobong (chimney, dan penukar kalor. Dalam penelitian ini, tangki dimodelkan secara lump dan dilakukan variasi daya awal reaktor dan ketinggian cerobong. Syarat batas model ditetapkan suhu bahan bakar maksimum 1400 °C, yang didasarkan pada titik didih larutan garam LiF-BeF2-ThF4-UF4. Analisis dilakukan dengan cara menghitung rugi tekanan total dan transfer kalor untuk variasi daya awal antara 1800-3000 MWth dan ketinggian cerobong antara 1-10 m. Hasil penelitian menunjukan semakin besar daya reaktor, maka tinggi tangki penampung bahan bakar dan tinggi alat penukar kalor yang dibutuhkan akan semakin besar, tejadi kenaikan suhu fluida pendingin dan suhu udara pendingin, dan menyebabkan kenaikan laju aliran masa fluida pendingin, sedangkan laju aliran masa udara menurun. Peningkatan ketinggian cerobong menyebabkan ketinggian tangki penampung bahan bakar dan ketinggian alat penukar kalor semakin menurun, penurunan suhu fluida pendingin, tetapi suhu udara meningkat, dan menyebabkan peningkatan laju aliran masa fluida pendingin, tetapi laju aliran masa udara akan semakin menurun. Kata kunci: PCMSR, cerobong, alat penukar kalor, variasi daya.   The Passsive Compact Molten Salat Reactor (PCMSR reactor is developed from MSR reactor. The PCMSR reactor design requires special place to temporarily storage for reactor fuel when incident occurs, such as when there is an accident which caused the temperature of the fuel increases. The tank consist of three interconnected parts, the reservoir liquid fuel, chimney, and the heat exchanger. In this research, the tank system is modeled based on

Sources of organic nitrogen at the serpentinite-hosted Lost City hydrothermal field.

Science.gov (United States)

Lang, S Q; Früh-Green, G L; Bernasconi, S M; Butterfield, D A

2013-03-01

The reaction of ultramafic rocks with water during serpentinization at moderate temperatures results in alkaline fluids with high concentrations of reduced chemical compounds such as hydrogen and methane. Such environments provide unique habitats for microbial communities capable of utilizing these reduced compounds in present-day and, possibly, early Earth environments. However, these systems present challenges to microbial communities as well, particularly due to high fluid pH and possibly the availability of essential nutrients such as nitrogen. Here we investigate the source and cycling of organic nitrogen at an oceanic serpentinizing environment, the Lost City hydrothermal field (30°N, Mid-Atlantic Ridge). Total hydrolizable amino acid (THAA) concentrations in the fluids range from 736 to 2300 nm and constitute a large fraction of the dissolved organic carbon (2.5-15.1%). The amino acid distributions, and the relative concentrations of these compounds across the hydrothermal field, indicate they most likely derived from chemolithoautotrophic production. Previous studies have identified the presence of numerous nitrogen fixation genes in the fluids and the chimneys. Organic nitrogen in actively venting chimneys has δ(15) N values as low as 0.1‰ which is compatible with biological nitrogen fixation. Total hydrolizable amino acids in the chimneys are enriched in (13) C by 2-7‰ compared to bulk organic matter. The distribution and absolute δ(13) C(THAA) values are compatible with a chemolithoautotrophic source, an attribution also supported by molar organic C/N ratios in most active chimneys (4.1-5.5) which are similar to those expected for microbial communities. In total, these data indicate nitrogen is readily available to microbial communities at Lost City. © 2013 Blackwell Publishing Ltd.

The application of borehole logging to characterize the hydrogeology of the Faultless site, Central Nevada Test Area

International Nuclear Information System (INIS)

Chapman, J.B.; Mihevc, T.M.; Lyles, B.F.

1994-08-01

The Central Nevada Test Area was the site of the Faultless underground nuclear test that could be a source of radionuclide contamination to aquifers in Hot Creek Valley, Nevada. Field studies in 1992 and 1993 have used hydrologic logging and water sampling to determine the adequacy of the current groundwater monitoring network and the status of water-level recovery to pre-shot levels in the nuclear chimney. The field studies have determined that there is a possibility for contaminant migration away from the Faultless event though the pre-event water level has not been attained, while new data raise questions about the ability of the current monitoring network to detect migration. Hydrologic logs from the postshot hole (drilled into the chimney created by the nuclear detonation) reveal inflow around 485 m below land surface. The physical and chemical characteristics of the inflow water indicate that its source is much deeper in the chimney, perhaps driven upward in a convection cell generated by heat near the nuclear cavity. Logging and sampling at monitoring wells HTH-1 and HTH-2 revealed that the completion of HTH-1 may be responsible for its elevated water level (as compared to pre-nuclear test levels) and may have also created a local mound in the water table in the alluvium that accounts for higher post-test water levels at HTH-2. This mound would serve to divert flow around the monitoring wells, so that only migration of contaminants through the underlying, higher pressure, volcanic units is currently monitored. A hydraulic high found in an abandoned hole located between the nuclear chimney and the monitoring wells further reduces the likelihood of HTH-1 or HTH-2 intercepting contaminant migration

An evaluation of water production from the Gasbuggy reentry well

International Nuclear Information System (INIS)

Power, Dean V.; Bowman, Charles R.

1970-01-01

During the gas production testing of the Gasbuggy chimney, water production rates increased from an initial 4 to 5 barrels per 10 6 standard cubic feet of gas to 40 to 50 barrels per 10 6 standard cubic feet of gas. This unexpected occurrence hampered operations and increased waste disposal costs. A model is developed which calculates the amount of water produced from condensation of water vapor through the cooling and expansion of the gas in the production tubing. Results from this model are compared with the observed water production from November of 1968 through May of 1969. This comparison shows that up to seven times more water is being produced at high gas flow rates than can be explained by condensed vapor, indicating that water is being introduced into the production tubing in particulate or liquid form. A correlation of excess water with the pressure, temperature and gas flow velocity parameters is performed to determine the relationship between this excess water and these parameters. It is found that the excess produced water varied linearly with downhole pressure when a threshold gas flow velocity was exceeded. The relationship is expressed by the equation H 2 0 (in barrels per day) =126.5-0.1473 BHP (in pounds per square inch). The threshold gas velocity for excess water production was found to be about 6 feet per second in the 7 in casing or 40 feet per second in the 2 7/8 in tubing. An examination of the radioactivity of the gas and water produced from GB-E indicates that the tritiated water vapor in the chimney and tubing has been diluted by extraneous water. The tritium in the gas decreased as expected from about 10.9 μCi/SCF in November 1968 to 6.2 μCi/SCF in late February 1969. During this same period, the tritium in the water decreased from about 1.2 μCi/ml to 0.12 μCi/ml. Examination of water chemistry, preshot and during the production testing, indicates that at early times when there was no excess water, the produced water was distilled

Numerical modelling of the process of heat transference, of the convective flow induced and the power generated in a wind power station; Modelizacion numerica del proceso de transferencia de calor, del flujo convectivo inducido y de la potencia generada en una central eolico solar

Energy Technology Data Exchange (ETDEWEB)

Hurtado, F. J.; Kaiser, A. S.; Zamora, B.; Lucas, M.; Viedma, A.

2008-07-01

A thermodynamic analysis for solar chimney power plant has been carried out by numerical simulation. A numerical model has been developed using the general purpose code Fluent to study heat transfer and convective flow within the chimney power plant. The {kappa}-{epsilon} turbulence model has been employed. A heat transfer, mass flow and power production numerical analysis has been carried out on different hours during the day, assuming steady state conditions. The numeric values obtained are 10% different from experimental measures. Once model has been validated, a numeric study about flow within power plant, heat transfer and mass flow has been carry out, and the non-dimensional parameters obtained have been compared with studies about free convection. (Author)

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.

The effect of fires on the development and appearance of medieval towns

Directory of Open Access Journals (Sweden)

Domen Kušar

2003-01-01

Full Text Available The occurrence of fires was one of the main dangers, which slowed down development of medieval towns. Frequent fires, whether they occurred due to carelessness, poorly maintained fireplaces and chimneys or military attacks, caused damage, particularly to those towns and buildings, which were constructed of inflammable materials such as timber and straw. In medieval times most towns were built using such materials, except those near the coast. Citizens tried to reduce fire hazards and the consequences of fires. With substitution of inflammable materials, apparatus and with the improved maintenance of fireplaces and chimneys, as well as other preventive measures, they influenced the development of towns and thus changed their architectural image.

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.

Utilization of the noble gases in studies of underground nuclear detonations

International Nuclear Information System (INIS)

Smith, C.F.

1973-01-01

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

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 (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 the deposited soft material was colonized only by the sulfate-reducing archaeum, Archaeoglobus. These samples (8 beehives, 4 open conduit smokers, one diffuser spire, from chimneys of known composition

Thermal-CFD Analysis of Combined Solar-Nuclear Cycle Systems.

Energy Technology Data Exchange (ETDEWEB)

Fathi, Nima [Univ. of New Mexico, Albuquerque, NM (United States); McDaniel, Patrick [Univ. of New Mexico, Albuquerque, NM (United States); Vorobieff, Peter [Univ. of New Mexico, Albuquerque, NM (United States); de Oliveira, Cassiano [Univ. of New Mexico, Albuquerque, NM (United States); Rodriguez, Salvador B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Aleyasin, Seyed Sobhan [Univ. of Manitoba (Canada)

2015-09-01

The aim of this paper is evaluating the efficiency of a novel combined solar-nuclear cycle. CFD-Thermal analysis is performed to apply the available surplus heat from the nuclear cycle and measure the available kinetic energy of air for the turbine of a solar chimney power plant system (SCPPS). The presented idea helps to decrease the thermal pollution and handle the water shortage supply for water plant by replacing the cooling tower by solar chimney power plant to get the surplus heat from the available warm air in the secondary loop of the reactor. By applying this idea to a typical 1000 MW nuclear power plant with a 0.33 thermal efficiency, we can increase it to 0.39.

Chemical mining of primary copper ores by use of nuclear technology

Energy Technology Data Exchange (ETDEWEB)

Lewis, A E [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-15

Chemical mining of primary copper ores, with nuclear explosives to break the ore and in-situ hydrostatic pressure to accelerate dissolution of primary ore minerals, may be feasible. A contained nuclear explosion well below the water table would be used to provide a mass of broken ore in a flooded 'chimney'. The hydrostatic pressure in the chimney should increase the solubility of oxygen in a water-sulfuric acid system enough to allow primary copper minerals such as chalcopyrite and bornite to be dissolved in an acceptably short time. Circulation and collection would be accomplished through drill holes. This method should be especially applicable to the deep portions of porphyry copper deposits that are not economical to mine by present techniques. (author)

Some important results from the air pollution distribution model STACKS (1988-1992)

International Nuclear Information System (INIS)

Erbrink, J.J.

1993-01-01

Attention is paid to the results of the study on the distribution of air pollutants by high chimney-stacks of electric power plants. An important product of the study is the integrated distribution model STACKS (Short Term Air-pollutant Concentrations Kema modelling System). The improvements and the extensions of STACKS are described in relation to the National Model, which has been used to estimate the environmental effects of individual chimney-stacks. The National Model shows unacceptable variations for high pollutant sources. Based on the results of STACKS revision of the National model has been taken into consideration. By means of the revised National Model a more realistic estimation of the environmental effects of electric power plants can be carried out

Particle-size distribution study: PILEDRIVER event

Energy Technology Data Exchange (ETDEWEB)

Rabb, David D [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-15

Reentry was made by mining into the chimney of broken rock created by a nuclear detonation in granite at a depth of 1500 feet. The chimney was 160 ft in radius and 890 ft high. An injection of radioactive melt was encountered at 300 ft from shot point. Radiochemical analyses determined that the yield of PILEDRIVER nuclear device was 61 {+-} 10 kt. Two samples of chimney rubble totalling over 5,000 lb were obtained during the postshot exploration. These samples of broken granite underwent screen analysis, a radioactivity-distribution study, and cursory leaching tests. The two samples were separated into 25 different size-fractions. An average of the particle-size data from the two samples showed that 17% of the material is between 20 mesh and I in.; 42% between 1 and 6 in.; and 34% between 6 in. and 3 ft. The distribution of radioactivity varies markedly with the particle size. The minus 100-mesh material comprizes less than 1.5% of the weight but contains almost 20% of the radioactivity. Small-scale batch-leaching tests showed that 25% of the radioactivity could be removed in a few hours by a film-percolation leach with distilled water, and 40% with dilute acid. Brief studies were made of the microfractures in the broken rock and of the radioactivity created by the PILEDRIVER explosion. (author)

Prognostication of the radioactive contamination with iodine 131, strontium 90 and cesium 137 of the air and soil after commissioning the ''Kozloduj'' nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Khristova, M; Paskalev, Z [Nauchno-Izsledovatelski Inst. po Radiologiya i Radiatsionna Khigiena, Sofia (Bulgaria)

1975-01-01

The content of iodine 131, strontium 90 and cesium 137 in the air (curie/l) and soil (curie/m/sup 2/ sec) in the area of the Kozloduj atomic power station (at a distance from 3 to 75 km from the chimney-stack of the power station) was determined. The concentrations of these radionuclides are determined under different meteorologic conditions: air temperature from -20/sup 0/C to +20/sup 0/C and a wind speed from 2 m/sec to 30 m/sec. The data show that at -20/sup 0/C radionuclide concentrations in the air decrease with increasing distance from the chimney-stack, regardless of the speed of the wind. At +20/sup 0/C radionuclide concentrations in the air increase with the distance from the chimney-stack, peak at a definite distance and then decrease. At 2 m/sec and speed this maximum is at a distance of 50 km from station. As the speed of the air increases, the peak moves nearer and remains about 30 km from the power station. Results on ground surface concentrations show that a trend is observed toward persistent decrease with distance from the power station. In rainy weather they are almost four times higher than in dry weather. The radionuclide concentrations on the ground surface will be comparable to their global deposits.

Particle-size distribution study: PILEDRIVER event

International Nuclear Information System (INIS)

Rabb, David D.

1970-01-01

Reentry was made by mining into the chimney of broken rock created by a nuclear detonation in granite at a depth of 1500 feet. The chimney was 160 ft in radius and 890 ft high. An injection of radioactive melt was encountered at 300 ft from shot point. Radiochemical analyses determined that the yield of PILEDRIVER nuclear device was 61 ± 10 kt. Two samples of chimney rubble totalling over 5,000 lb were obtained during the postshot exploration. These samples of broken granite underwent screen analysis, a radioactivity-distribution study, and cursory leaching tests. The two samples were separated into 25 different size-fractions. An average of the particle-size data from the two samples showed that 17% of the material is between 20 mesh and I in.; 42% between 1 and 6 in.; and 34% between 6 in. and 3 ft. The distribution of radioactivity varies markedly with the particle size. The minus 100-mesh material comprizes less than 1.5% of the weight but contains almost 20% of the radioactivity. Small-scale batch-leaching tests showed that 25% of the radioactivity could be removed in a few hours by a film-percolation leach with distilled water, and 40% with dilute acid. Brief studies were made of the microfractures in the broken rock and of the radioactivity created by the PILEDRIVER explosion. (author)

Project requirements for reconstruction of the RA reactor ventilation system, Task 2.8. Measurement of radioactive iodine and other isotopes contents in the gas system of the RA reactor, Annex of the task

International Nuclear Information System (INIS)

Vujisic, Lj. et al

1981-01-01

This report is a supplement to the task 2.8. When planning and constructing the ventilation system, it was found that it is necessary to perform additional experiments during RA reactor operation at 2 MW power level for a longer period. In addition to the helium system, the potential source of radioactive pollutants is the space below the upper water shielding of the reactor. All the experimental and fuel channels are ending in this space. During repair and fuel exchange radioactivity can be released in this space. For that reason this space is important when planing and designing the filtration system for incidental conditions or planned dehermetisation of the reactor. The third point where radioactive isotope identification was done, was the entrance into the chimney during steady state operation and planned dehermetisation of the reactor. The following samples were measured: gas system during reactor operation at 2 MW power; entrance into the chimney during last 48 hours of reactor operation at 2 MW power; sample on the platform under the upper water shield with the opened fuel channel after the reactor shutdown; and simultaneously with the latter, measurement at the entrance to the chimney. This annex contains the list of identified radioactive isotopes, volatile and gaseous as well as concentration of volatile 131 I on the adsorbents [sr

Annual report and accounts 1980/81. [UK; Solid Fuels Avisory Service; book

Energy Technology Data Exchange (ETDEWEB)

1981-01-01

The work of the Solid Fuel Advisory Service during 1980/81 is described under the headings: sales promotion, market research, service to the public, technical, chimneys and training. The accounts are then presented.

Page 1 508 Ethiopian Journal of Environmental Studies ...

African Journals Online (AJOL)

USER

2014-08-06

Aug 6, 2014 ... Midlands State University, P Bag 9055, Gweru, Zimbabwe. Abstract ... absence of cleaner production technologies. (Mbowa, 2002 .... Table 3: Average air quality measurements from chimneys for period before and during CP.

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

Mineralizing Filamentous Bacteria from the Prony Bay Hydrothermal Field Give New Insights into the Functioning of Serpentinization-Based Subseafloor Ecosystems.

Science.gov (United States)

Pisapia, Céline; Gérard, Emmanuelle; Gérard, Martine; Lecourt, Léna; Lang, Susan Q; Pelletier, Bernard; Payri, Claude E; Monnin, Christophe; Guentas, Linda; Postec, Anne; Quéméneur, Marianne; Erauso, Gaël; Ménez, Bénédicte

2017-01-01

Despite their potential importance as analogs of primitive microbial metabolisms, the knowledge of the structure and functioning of the deep ecosystems associated with serpentinizing environments is hampered by the lack of accessibility to relevant systems. These hyperalkaline environments are depleted in dissolved inorganic carbon (DIC), making the carbon sources and assimilation pathways in the associated ecosystems highly enigmatic. The Prony Bay Hydrothermal Field (PHF) is an active serpentinization site where, similar to Lost City (Mid-Atlantic Ridge), high-pH fluids rich in H 2 and CH 4 are discharged from carbonate chimneys at the seafloor, but in a shallower lagoonal environment. This study aimed to characterize the subsurface microbial ecology of this environment by focusing on the earliest stages of chimney construction, dominated by the discharge of hydrothermal fluids of subseafloor origin. By jointly examining the mineralogy and the microbial diversity of the conduits of juvenile edifices at the micrometric scale, we find a central role of uncultivated bacteria belonging to the Firmicutes in the ecology of the PHF. These bacteria, along with members of the phyla Acetothermia and Omnitrophica , are identified as the first chimneys inhabitants before archaeal Methanosarcinales . They are involved in the construction and early consolidation of the carbonate structures via organomineralization processes. Their predominance in the most juvenile and nascent hydrothermal chimneys, and their affiliation with environmental subsurface microorganisms, indicate that they are likely discharged with hydrothermal fluids from the subseafloor. They may thus be representative of endolithic serpentinization-based ecosystems, in an environment where DIC is limited. In contrast, heterotrophic and fermentative microorganisms may consume organic compounds from the abiotic by-products of serpentinization processes and/or from life in the deeper subsurface. We thus propose

Exploration Method Development for hydrothermal plume hunting by XCTD

Science.gov (United States)

Kitagawa, Y.; Ikeda, M.; Kadoshima, K.; Koizumi, Y.; Nakano, J.; Asakawa, E.; Sumi, T.

2017-12-01

J-MARES (Research and Development Partnership for Next Generation Technology of Marine Resources Survey, JAPAN) has been designing a low-cost and high-efficiency exploration system for seafloor hydrothermal massive sulfide deposits in "Cross-ministerial Strategic Innovation Promotion Program (SIP)" granted by the Cabinet Office, Government of Japan since 2014. We proposed hydrothermal plume hunting by XCTD (eXpendables Conductivity, Temperature and Depth). We applied this method to an area of interest more than 100km x 100km over Okinawa Trough, including some known seafloor massive sulfide deposits. Generally, hydrothermal plume exploration has been by ship mounted with MBES (Multi Beam Echo Sounder) or AUV with sound anomaly observation. However, these methods have to charter the sophisticated ship costly. On the other hand, throw-in type water quality meters (eg. XCTD and XBT) can be low-cost and easily operable. Moreover, that can make a quick look at seawater temperature and conductivity even in rough waters.Firstly, we confirmed XCTD probes position on the seafloor by ROV mounted deep-sea high vision camera. As a result of the test, probes swept downstream about 40 m in horizontal distance from throwing positions with about 1,600m in water depth. Following the previous test results, we had performed to the next test that confirmed detection range of hydrothermal plume at the chimney of North Mound in Izena Cauldron, so we had caught anomaly of seawater temperature and conductivity successfully which could be possibly derived from hydrothermal activities. Although averaged seawater temperature at a depth of 1500 m or more was about 3.95 degrees C, near the chimney was about 4.93 degrees C. The temperature anomalies originated from the hydrothermal plumes could be distributed at most 30m in horizontal distance and became smaller away from the chimney. Moreover, temperature anomaly mass of sea water tended to move upward in depth with distance away from the

Lower parts of Temelin nuclear power plant cooling towers

International Nuclear Information System (INIS)

Sebek, J.

1988-01-01

The progress of work is described in detail on the foundations and lower parts of the cooling towers of the Temelin nuclear power plant. The cooling tower is placed on a reinforced concrete footing of a circular layout. Support pillars are erected on the reinforced concrete continuous footing. They consists of oblique shell stanchions. Inside, the footing joins up to monolithic wall and slab structures of the cooling tower tub. The tub bottom forms a foundation plate supporting prefab structures of the cooling tower inner structural systems. The framed support of the chimney shell consists of 56 pairs of prefabricated oblique stanchions. Following their erection into the final position and anchoring in the continuous footing, the concreting of the casing can start of the reinforced conrete chimney. (Z.M.). 3 figs

Activity release from damaged fuel during the Paks-2 cleaning tank incident in the spent fuel storage pool

International Nuclear Information System (INIS)

Hozer, Zoltan; Szabo, Emese; Pinter, Tamas; Varju, Ilona Baracska; Bujtas, Tibor; Farkas, Gabor; Vajda, Nora

2009-01-01

During crud removal operations the integrity of 30 fuel assemblies was lost at high temperature at the unit No. 2 of the Paks NPP. Part of the fission products was released from the damaged fuel into the coolant of the spent fuel storage pool. The gaseous fission products escaped through the chimney from the reactor hall. The volatile and non-volatile materials remained mainly in the coolant and were collected on the filters of water purification system. The activity release from damaged fuel rods during the Paks-2 cleaning tank incident was estimated on the basis of coolant activity concentration measurements and chimney activity data. The typical release rate of noble gases, iodine and caesium was 1-3%. The release of non-volatile fission products and actinides was also detected.

Activity release from damaged fuel during the Paks-2 cleaning tank incident in the spent fuel storage pool

Energy Technology Data Exchange (ETDEWEB)

Hozer, Zoltan, E-mail: hozer@aeki.kfki.h [Hungarian Academy of Sciences KFKI Atomic Energy Research Institute, H-1525 Budapest 114, P.O. Box 49 (Hungary); Szabo, Emese [Hungarian Academy of Sciences KFKI Atomic Energy Research Institute, H-1525 Budapest 114, P.O. Box 49 (Hungary); Pinter, Tamas; Varju, Ilona Baracska; Bujtas, Tibor; Farkas, Gabor [Nuclear Power Plant Paks, H-7031 Paks, P.O. Box 71 (Hungary); Vajda, Nora [Institute of Nuclear Techniques, Budapest University of Technology and Economics, H-1521 Budapest, Muegyetem rakpart 9 (Hungary)

2009-07-01

During crud removal operations the integrity of 30 fuel assemblies was lost at high temperature at the unit No. 2 of the Paks NPP. Part of the fission products was released from the damaged fuel into the coolant of the spent fuel storage pool. The gaseous fission products escaped through the chimney from the reactor hall. The volatile and non-volatile materials remained mainly in the coolant and were collected on the filters of water purification system. The activity release from damaged fuel rods during the Paks-2 cleaning tank incident was estimated on the basis of coolant activity concentration measurements and chimney activity data. The typical release rate of noble gases, iodine and caesium was 1-3%. The release of non-volatile fission products and actinides was also detected.

An evaluation of water production from the Gasbuggy reentry well

Energy Technology Data Exchange (ETDEWEB)

Power, Dean V; Bowman, Charles R [El Paso Natural Gas Company (United States)

1970-05-01

During the gas production testing of the Gasbuggy chimney, water production rates increased from an initial 4 to 5 barrels per 10{sup 6} standard cubic feet of gas to 40 to 50 barrels per 10{sup 6} standard cubic feet of gas. This unexpected occurrence hampered operations and increased waste disposal costs. A model is developed which calculates the amount of water produced from condensation of water vapor through the cooling and expansion of the gas in the production tubing. Results from this model are compared with the observed water production from November of 1968 through May of 1969. This comparison shows that up to seven times more water is being produced at high gas flow rates than can be explained by condensed vapor, indicating that water is being introduced into the production tubing in particulate or liquid form. A correlation of excess water with the pressure, temperature and gas flow velocity parameters is performed to determine the relationship between this excess water and these parameters. It is found that the excess produced water varied linearly with downhole pressure when a threshold gas flow velocity was exceeded. The relationship is expressed by the equation H{sub 2}0 (in barrels per day) =126.5-0.1473 BHP (in pounds per square inch). The threshold gas velocity for excess water production was found to be about 6 feet per second in the 7 in casing or 40 feet per second in the 2 7/8 in tubing. An examination of the radioactivity of the gas and water produced from GB-E indicates that the tritiated water vapor in the chimney and tubing has been diluted by extraneous water. The tritium in the gas decreased as expected from about 10.9 {mu}Ci/SCF in November 1968 to 6.2 {mu}Ci/SCF in late February 1969. During this same period, the tritium in the water decreased from about 1.2 {mu}Ci/ml to 0.12 {mu}Ci/ml. Examination of water chemistry, preshot and during the production testing, indicates that at early times when there was no excess water, the produced

June 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...

Global Journal of Environmental Sciences - Vol 4, No 2 (2005)

African Journals Online (AJOL)

Open Access DOWNLOAD FULL TEXT Subscription or Fee Access ... Monitoring air pollutants due to gas flaring using rain water · EMAIL FREE FULL TEXT ... from an industrial chimney · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Old Hickory Lake Appendix M To Park Management Shoreline Management Plan

Science.gov (United States)

2014-07-01

attractors, establishment of nesting/forage habitat such as monarch butterfly way stations, construction of chimney swift towers, etc. 22. Leases...Elaeagnus umbellata Thunb.) Japanese Bush honeysuckles (Lonicera japonica.) Amur Bush honeysuckle (Lonicera maackii.) Marrows Bush honeysuckle (Lonicera

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)

Scenarios for solar thermal energy applications in Brazil

International Nuclear Information System (INIS)

Martins, F.R.; Abreu, S.L.; Pereira, E.B.

2012-01-01

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/m 2 and averages of daily solar irradiation are larger than 5.0 kW h/m 2 /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.

High-efficiency wind turbine

Science.gov (United States)

Hein, L. A.; Myers, W. N.

1980-01-01

Vertical axis wind turbine incorporates several unique features to extract more energy from wind increasing efficiency 20% over conventional propeller driven units. System also features devices that utilize solar energy or chimney effluents during periods of no wind.

Taming Windscale's piles

International Nuclear Information System (INIS)

Adams, A.L.

1989-01-01

The options as to what to do with the Windscale Piles are being assessed before a final decision on decommissioning is made. Both Piles were shutdown in 1957 following the fire in the Pile number 1. Pile 1 still contains 22 tons of natural uranium fuel. The details of graphite moderator content, biological shielding and other components and containment are given. The fuel and isotope channels in Pile 2 have been examined and the air and water ducts have been inspected. The chimneys of both Piles are contaminated and all entrances have been sealed. Before any work starts the air outlet ducts will be sealed from the chimney and a ventilation system installed. A manipulator is being prepared to remove the remaining fuel elements from both Piles. The proposed decommissioning programme for both Piles is outlined. (U.K.)

field characteristics and other properties of a fireclay

African Journals Online (AJOL)

USER

is due to the low plasticity of the fireclay which manifests too, in low air-drying and firing shrinkages. At elevated ... conventional brick- making clays, fireclays are usually mined at ..... chimney linings, pottery kilns, blast furnaces, and reheating ...

Evidence of paleo-cold seep activity from the Bay of Bengal, offshore India

Digital Repository Service at National Institute of Oceanography (India)

Mazumdar, A.; Dewangan, P.; Joao, H.M.; Peketi, A.; Khosla, V.R.; Kocherla, M.; Badesab, F.K.; Joshi, R.K.; Roxanne, P.; Ramamurty, P.B.; Karisiddaiah, S.M.; Patil, D.J.; Dayal, A.M.; Ramprasad, T.; Hawkesworth, C.J.; Avanzinelli, R.

clam shells, chimneys, shell breccias with high Mg calcite cement, and pyrite within this zone suggest seepage of methane and sulfide-bearing fluid to the seafloor in the past. Highly depleted carbon isotopic values (delta sup(13)C ranges from -41...

Geochemical Investigation of Vertical Migration of Petroleum ...

African Journals Online (AJOL)

Dr. K.J. Umar

chimneys over faults in an overpressured zone in the western part of ... Haltenbanken area is part of a passive continental margin between the Møre Basin and the Trøndelag. Platform ... The petroleum accumulations in the Heidrun field and in.

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

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

EXPERIMENTAL STUDY IN NATURAL CONVECTION

African Journals Online (AJOL)

PROF. BARTH EKWEME

often heavily depend on imports of oil and gas. However, they have one of ... Table 1: Main features of the Manzanares power plant Sclaich et al., (2005). Tower height. 194.6 m ..... chimney cycle analysis with system loss and solar collector ...

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.

Recovering heat from waste air from stables

Energy Technology Data Exchange (ETDEWEB)

1983-01-01

A milk cow gives off 35.7 kW h/d via its body, excreta and urine. 68.4% of this is body heat. Part of this waste heat escapes with the waste air from the cowsheds. The heat can be recovered from the waste air by an air/air heat exchanger. The air is collected and taken to a heat exchanger. In the heat exchanger, fresh air is heated by the waste air, and is distributed over the cowshed by a system of ducts. The heated waste air escapes through a central chimney at the end of the heat exchanger. It is sensible to fit the heat exchanger above the cowshed roof, if there is sufficient space available and the chimney should run upwards from the cowshed. A double heat exchanger makes it possible to allocate each half of the cowshed to half of the heat exchanger.

Evaluation of gas emissions and environmental impact of a Cuban thermal power plant

International Nuclear Information System (INIS)

Colas Aroche, Juan Alberto; Alvarez Hernandez, Orlando H; Fuentes Quevedo, Eduardo; Teutelo Nunnez, Raisa

2006-01-01

The present work shows the results obtained in the characterization of gas emissions and the impact of two fire-tube boilers in a Cuban thermal power plant. The results of the SO 2 and NO X sampling were collected in specific solutions for each pollutant. The sampling of suspended particulates in chimneys/pipes/stacks was made by collecting them in a filterholder for their analysis by means of the gravimetric method. Flow measurements were also made by using pressure sensors of Pilot tube-type speedometers. The dispersion modelling of pollutants poured out of the chimneys was developed running the program for the concentration calculation from continuous industrial sources and following the methodology approved by the Cuban standard according to Berliand model. The authors conclude that when burning national crude oil in the studied boilers, sulphur dioxide concentrations and suspended particulates are higher than the internationally standardized level

Agriculture and smoke pollution

Energy Technology Data Exchange (ETDEWEB)

Jones, H T

1940-01-01

The effects of smoke fumes on the growth of crops and on the reaction of soils in Yorkshire during the last 15 years are reported. Attention is focused on the scorching effect on vegetation caused by acid rain, and the indirect effect of these acids on plants by reducing the lime status of the soil. In cities and towns the worst offenders are domestic chimneys which contribute 150 tons of sulfur to the atmosphere every week. In less densely populated industrial districts, the bulk of the fumes are contributed by industrial chimneys and by the smouldering pit heaps of collieries. The symptoms of smoke damage on wheat are the scorching of the tip of the leaf, followed by a yellowing of the remainder of the leaf. Adequate liming greatly increases the resistance of crops to attacks by fumes. The effect of acid fumes on the soil is also discussed.

Experimental and numerical investigations on flashing-induced instabilities in a single channel

Energy Technology Data Exchange (ETDEWEB)

Marcel, Christian P.; Rohde, M.; Van Der Hagen, T.H.J.J. [Department of Physics of Nuclear Reactors, Delft University of Technology (TUDelft), Delft, 2629 JB (Netherlands)

2009-11-15

During the start-up phase, natural circulation BWRs (NC-BWRs) need to be operated at low pressure conditions. Such conditions favor flashing-induced instabilities due to the large hydrostatic pressure drop induced by the tall chimney. Moreover, in novel NC-BWR designs the steam separation is performed in the steam separators which create large pressure drops at the chimney outlet, which effect on stability has not been investigated yet. In this work, flashing-induced oscillations occurring in a tall, bottom heated channel are numerically investigated by using a simple linear model with three regions and an accurate implementation for estimating the water properties. The model is used to investigate flashing-induced instabilities in a channel for different values of the core inlet friction value. The results are compared with experiments obtained by using the CIRCUS facility at the same conditions, showing a good agreement. In addition, the experiments on flashing-induced instabilities are presented in a novel manner allowing visualizing new details of the phenomenon numerical stability investigations on the effect of the friction distribution are also done. It is found that by increasing the total restriction in the channel the system is destabilized. In addition, the chimney outlet restriction has a stronger destabilizing effect than the core inlet restriction. A stable two-phase region is observed prior to the instabilities in the experiments and the numerical simulations which may help to pressurize the vessel of NC-BWRs and thus reducing the effects of flashing instabilities during start-up. (author)

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

Science.gov (United States)

2010-04-28

... employer must ensure that the frame of the hoist machine is a self-supporting, rigid, welded-steel...-machine structure. 10. Personnel Cage (a) Construction. A personnel cage must be of steel-frame..., inspects, and demolishes tall chimneys made of reinforced concrete, brick, and steel. This work, which...

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.

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.

Deeply-sourced formate fuels sulfate reducers but not methanogens at Lost City hydrothermal field.

Science.gov (United States)

Lang, Susan Q; Früh-Green, Gretchen L; Bernasconi, Stefano M; Brazelton, William J; Schrenk, Matthew O; McGonigle, Julia M

2018-01-15

Hydrogen produced during water-rock serpentinization reactions can drive the synthesis of organic compounds both biotically and abiotically. We investigated abiotic carbon production and microbial metabolic pathways at the high energy but low diversity serpentinite-hosted Lost City hydrothermal field. Compound-specific 14 C data demonstrates that formate is mantle-derived and abiotic in some locations and has an additional, seawater-derived component in others. Lipids produced by the dominant member of the archaeal community, the Lost City Methanosarcinales, largely lack 14 C, but metagenomic evidence suggests they cannot use formate for methanogenesis. Instead, sulfate-reducing bacteria may be the primary consumers of formate in Lost City chimneys. Paradoxically, the archaeal phylotype that numerically dominates the chimney microbial communities appears ill suited to live in pure hydrothermal fluids without the co-occurrence of organisms that can liberate CO 2 . Considering the lack of dissolved inorganic carbon in such systems, the ability to utilize formate may be a key trait for survival in pristine serpentinite-hosted environments.

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.

From continuum analytical description to discrete numerical modelling of localized fluidization in granular media

Directory of Open Access Journals (Sweden)

Puig i Montellà Eduard

2017-01-01

Full Text Available We present analytical and numerical results on localized fluidization within a granular layer subjected to a local injection of fluid. As the injection rate increases the three different regimes previously reported in the literature are recovered: homogeneous expansion of the bed, fluidized cavity in which fluidization starts developing above the injection area, and finally the chimney of fluidized grains when the fluidization zone reaches the free surface. The analytical approach is at the continuum scale, based on Darcy’s law and Therzaghi’s effective stress principle. It provides a good description of the phenomenon as long as the porosity of the granular assembly remains relatively homogeneous. The numerical approach is at the particle scale based on the coupled DEM-PFV method. It tackles the more heterogeneous situations which occur at larger injection rates. A direct link is evidenced between the occurrence of the different regimes of fluidization and the injection aperture. Finally, the merging of chimneys in case of two injection points is investigated.

Thermal-hydraulics stability of natural circulation BWR under startup. Flashing effects

International Nuclear Information System (INIS)

Hu, Rui; Kazimi, Mujid S.

2009-01-01

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)

On Day-to-Day Variability of Global Lightning Activity as Quantified from Background Schumann Resonance Observations

Science.gov (United States)

Mushtak, V. C.; Williams, E. R.

2011-12-01

Among the palette of methods (satellite, VLF, ELF) for monitoring global lightning activity, observations of the background Schumann resonances (SR) provide a unique prospect for estimating the integrated activity of global lightning activity in absolute units (coul2 km2/sec). This prospect is ensured by the SR waves' low attenuation, with wavelengths commensurate with the dimensions of dominant regional lightning "chimneys", and by the accumulating methodology for background SR techniques. Another benefit is the reduction of SR measurements into a compact set of resonance characteristics (modal frequencies, intensities, and quality factors). Suggested and tested in numerical simulations by T.R. Madden in the 1960s, the idea to invert the SR characteristics for the global lightning source has been farther developed, statistically substantiated, and practically realized here on the basis of the computing power and the quantity of experimental material way beyond what the SR pioneers had at their disposal. The critical issue of the quality of the input SR parameters is addressed by implementing a statistically substantiated sanitizing procedure to dispose of the fragments of the observed time series containing unrepresentative elements - local interference of various origin and strong ELF transients originating outside the major "chimneys" represented in the source model. As a result of preliminary research, a universal empirical sanitizing criterion has been established. Due to the fact that the actual observations have been collected from a set of individually organized ELF stations with various equipment sets and calibration techniques, the relative parameters in both input (the intensities) and output (the "chimney" activities) are being used as far as possible in the inversion process to avoid instabilities caused by calibration inconsistencies. The absolute regional activities - and so the sought for global activity in absolute units - is determined in the

16 CFR 1305.5 - Findings.

Science.gov (United States)

2010-01-01

... when air currents in the home are created by downdrafts from a fireplace chimney or other activities... not permanently bound into artificial fireplace logs would be in respirable form, the risk associated... in certain gas-buring fireplace systems, which glow to give the appearance of real burning embers...

Seafloor Topographic Analysis in Staged Ocean Resource Exploration

Science.gov (United States)

Ikeda, M.; Okawa, M.; Osawa, K.; Kadoshima, K.; Asakawa, E.; Sumi, T.

2017-12-01

J-MARES (Research and Development Partnership for Next Generation Technology of Marine Resources Survey, JAPAN) has been designing a low-expense and high-efficiency exploration system for seafloor hydrothermal massive sulfide deposits in "Cross-ministerial Strategic Innovation Promotion Program (SIP)" granted by the Cabinet Office, Government of Japan since 2014. We designed a method to focus mineral deposit prospective area in multi-stages (the regional survey, semi-detail survey and detail survey) by extracted topographic features of some well-known seafloor massive sulfide deposits from seafloor topographic analysis using seafloor topographic data acquired by the bathymetric survey. We applied this procedure to an area of interest more than 100km x 100km over Okinawa Trough, including some known seafloor massive sulfide deposits. In Addition, we tried to create a three-dimensional model of seafloor topography by SfM (Structure from Motion) technique using multiple image data of Chimney distributed around well-known seafloor massive sulfide deposit taken with Hi-Vision camera mounted on ROV in detail survey such as geophysical exploration. Topographic features of Chimney was extracted by measuring created three-dimensional model. As the result, it was possible to estimate shape of seafloor sulfide such as Chimney to be mined by three-dimensional model created from image data taken with camera mounted on ROV. In this presentation, we will discuss about focusing mineral deposit prospective area in multi-stages by seafloor topographic analysis using seafloor topographic data in exploration system for seafloor massive sulfide deposit and also discuss about three-dimensional model of seafloor topography created from seafloor image data taken with ROV.

Measurement of vapor behavior in tight-lattice bundles by neutron radiography

International Nuclear Information System (INIS)

Kureta, Masatoshi; Akimoto, Hajime

2004-01-01

Three-dimensional and instantaneous void fractions in tight-lattice 7-rod and 14-rod bundles were measured by neutron radiography in order to make clear the flow behavior and to verify the advanced fine-mesh numerical analysis codes for the R and D of the Reduced-Moderation Water Reactors (RMWR). Time-averaged 3D void fraction distribution is evaluated with the spatial resolution of 0.1 - 0.2 mm using neutron tomography, and consecutive change of vapor behavior is observed quantitatively with time step of 1 ms using high-frame-rate neutron radiography (HFR-NR). In this paper, void fraction distribution and vapor behavior of flow boiling of water in tight-lattice rod bundles are focused on and discussed based on the obtained results. 'High void fraction spot', 'void drift phenomenon', and 'vapor chimney' were observed under atmospheric pressure conditions. Here, 'high void fraction spot' indicates that high void fraction regions are appeared between adjacent rods, narrow space, at/near point of net vapor generation region. 'Void drift' and 'vapor chimney' represent that high void fraction region moves to wide triangular space and is formed a vapor flow channel so-called 'vapor chimney'. It was confirmed from the time-averaged 3D data that void fraction in the center is higher than that in the periphery. On the other hand, it was found from the HFR-NR experiments that big vapor bubbles and/or cluster flow upward intermittently not only in the center but in the periphery of the channel and, therefore, point of net vapor generation is scattered statistically in wide region. (author)

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

Study of heat removal by natural convection from the internal core catcher in PFBR using water model experiments

International Nuclear Information System (INIS)

Jasmin Sudha, A.; Punitha, G.; Das, S.K.; Lydia, G.; Murthy, S.S.; Malarvizhi, B.; Harvey, J.; Kannan, S.E.

2005-01-01

Full text of publication follows: In the event of a core meltdown accident in a Fast Breeder Reactor, the molten core material settling on the bottom of the main vessel can endanger the structural integrity of the main vessel. In the design of Prototype Fast Breeder Reactor in India, the construction of which is about to commence, a core catcher is provided as the internal core retention device to collect and retain the core debris in a coolable configuration. Heat transfer by natural convection above and below the core catcher plate, in the zone beneath the core support structure is evaluated from water mockup experiments in the 1:4 geometrically scaled setup. These studies were undertaken towards comparison of experimentally measured temperatures at different locations with the numerical results. The core catcher assembly consists of a core catcher plate, a heat shield plate and a chimney. Decay heat from the core debris is simulated by electrical heating of the heat shield plate. An opening is provided in the cover plate to reproduce the situation in the actual accident where the core debris would have breached a part of the core support structure. Experiments were carried out with different heat flux levels prevailing upon the heat shield plate. Temperature monitoring was done at more than 100 locations, distributed both on the solid components and in water. The temperature data was analysed to get the temperature profile at different steady state conditions. Flow visualisation was also carried out using water soluble dye to establish the direction of the convective currents. The captured images show that water flows through the slots provided in the top portion of the chimney in the upward direction as evidenced from the diffusion of dye injected inside the chimney. Both the temperature data and flow visualisation confirm mixing of water through the opening in the core support structure which indicates that natural convection is set up in that zone

Thick massive gas hydrate deposits were revealed by LWD in Off-Joetsu area, eastern margin of Japan Sea.

Science.gov (United States)

Tanahashi, M.; Morita, S.; Matsumoto, R.

2016-12-01

GR14 and HR15 survey cruises, which were dedicated to the LWD (Logging While Drilling), were carried out in summers of 2014 and 2015, respectively, by Meiji University and Geological Survey of Japan, AIST to explore the "gas chimney" structures in eastern margin of Japan Sea. Shallow (33 to 172m-bsf, average 136m-bsf) 33 LWD drilling were performed in Oki Trough, Off-Joetsu, and Mogami Trough areas along eastern margin of Japan Sea during two cruises. Schlumberger LWD tools, GeoVISION (resistivity), TeleScope, ProVISION (NMR) and SonicVISION were used during GR14. NeoScope (neutron) was added and SonicScope was replaced for SonicVISION during HR14. The data quality was generally good. "Gas chimney" structures with acoustic blanking columns on the high frequency seismic sections with mound and pockmark morphologic features on the sea bottom, are well developed within survey areas. Every LWD records taken from gas chimney structures during the cruises show high resistivity and acoustic velocity anomalies which suggest the development of gas hydrate. Characteristic development of massive gas hydrate was interpreted at the Umitaka CW mound structure, Off-Joetsu. The mound lies at 890-910m in water depth and has very rough bottom surface, regional high resistivity, regional high heat flow, several natural seep sites, 200m x 300m area, and 10-20m height. 8 LWD holes, J18L to J21L and J23L to J26L, were drilled on and around the mound. There are highly anomalous intervals which suggest the development of massive gas hydrate at J24L, with high resistivity, high Vp and Vs, high neutron porosity, low natural gamma ray intensity, low neutron gamma density, low NMR porosity, low NMR permeability, low formation sigma, from 10 to 110m-bsf with intercalating some thin less hydrate layers. It is interpreted that there is several tens of meter thick massive gas hydrate in the gas chimney mound. It is partly confirmed by the later nearby coring result which showed the repetition of

Growth of a Hydrate Mound in the Sea of Japan over 300 ka as Revealed by U-Th Ages of MDAC and by H2S Concentrations of Massive Hydrates

Science.gov (United States)

Matsumoto, R.; Snyder, G. T.; Hiruta, A.; Kakizaki, Y.; Huang, C. Y.; Shen, C. C.

2017-12-01

The geological and geophysical exploration of gas hydrate in the Sea of Japan has revealed that hydrates occur as thick massive deposits within gas chimneys which often give rise to pingo-like hydrate mounds on the seafloor. We examine one case in which LWD has demonstrated anomalous profiles including both very low natural gamma ray (<10 API) and high acoustic velocities (2.5 to 3.5 km/s) extending down to 120mbsf, the base of gas hydrate stability (BGHS)[1]. Both conventional and pressure coring have confirmed thick, massive deposits of pure-gas hydrates. Hydrates in the shallow subsurface (< 20mbsf) are characterized by high H2S concentrations corresponding to AOM-induced production of HS-. The deeper hydrates generally have negligible amounts of H2S, with occasional exceptions in which H2S is moderately high. These observations lead us to conclude that both the re-equilibration and growth of hydrates in high CH4 and low to zero H2S conditions has continued during burial, and that this ongoing growth is an essential processes involved in the development of massive hydrates in the Sea of Japan.Regardless of depth, the Japan Sea gas hydrates are closely associated with 13-C depleted, methane-derived authigenic carbonates (MDACs). These MDACs are considered to have been formed at near-SMT depths as a response to increased alkalinity caused by AOM and, as such, MDACs are assumed to represent approximate paleo-seafloor at times of enhanced methane flux and intensive accumulation of gas hydrate in shallow subsurface. U-Th ages of MDACs collected from various depths in a mound-chimney system in central Joetsu Spur have revealed that the paleo-seafloor of 300 ka is presently situated at 30 to 55 mbsf within the gas chimney, in contrast to off-mound sites where it is situated at 100 mbsf. This suggests that at 300 ka the mound stood as a "hydrate-pingo" of 70 m high relative to the surrounding sea floor. At this time, the BGHS shoaled upwards 10m due to eustatic sea

static analysis of circular cylindrical shell under hydrostatic and ring

African Journals Online (AJOL)

DEPT OF AGRICULTURAL ENGINEERING

(Golzan et al, 2008). Circular cylindrical shells are used in a large variety of civil engineering structures, e.g. off-shore platforms, chimneys, silos, pipelines, bridge arches or wind turbine towers (Winterstetter et al, 2002). This work is concerned with the analysis of circular cylindri- cal shell subjected to hydrostatic pressure in.

Hydroaerothermal investigations conducted in the USSR to justify the construction of large cooling towers

International Nuclear Information System (INIS)

Goncharov, V.V.

1989-01-01

The multi-purpose task of improving water cooling systems of thermal and nuclear power plants is aimed at the development of efficient designs of cooling towers and other types of industrial coolers which call for comprehensive scientific justification. Cooling towers of 60-70 thou m 3 /h capacity with a chimney height of 130 m and those of 80-100 thou m 3 /h capacity with a chimney height of 150 m were developed. For circulating water systems of large power plants the design of a counterflow chimney cooling tower of 180 thou m 3 /h capacity has been recently developed. At present the work is being conducted on developing a new three-cell cooling tower featuring high reliability, operational flexibility and cost-effectiveness of the design. This cooling tower, besides having higher operating reliability than the conventional one of circular shape, can ensure the commissioning, current repairs and overhauls of water cooling arrangements in a cell-wise sequence, i.e. without shutting down the power generating units. Laboratory and field investigations of the spray-type cooling towers having no packing (fill), studies on heat and mass exchanges processes, aerodynamics of droplet flows and new designs of sprayers made it possible to come to a conclusion that their cooling capacity can be substantially increased and brought up to the level of the cooling towers with film packings. The pilot cooling towers were designed according to the counterflow, crossflow and cross-counterflow schemes. The basic investigation method remains to be the experimental one. On the test rigs and aerodynamic models the heat and mass transfer and aerodynamic resistance coefficients are determined. These studies and subsequent calculations are based on the heat balance equation

Summary of results of underground engineering experience

Energy Technology Data Exchange (ETDEWEB)

Holzer, F [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1969-07-01

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 {mu}Ci/ft{sup 3} and 1.5 {mu}Ci/ft{sup 3} 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)

Summary of results of underground engineering experience

International Nuclear Information System (INIS)

Holzer, F.

1969-01-01

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/ft 3 and 1.5 μCi/ft 3 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)

Investigation of Effect Additive Phase Change Materials on the Thermal Conductivity

Science.gov (United States)

Nakielska, Magdalena; Chalamoński, Mariusz; Pawłowski, Krzysztof

2017-10-01

The aim of worldwide policy is to reduce the amount of consumed energy and conventional fuels. An important branch of the economy that affects the energy balance of the country is construction industry. In Poland, since January 1st, 2017 new limit values have been valid regarding energy saving and thermal insulation of buildings. To meet the requirements of more and more stringent technical and environmental standards, new technological solutions are currently being looked for. When it comes to the use of new materials, phase-change materials are being widely introduced into construction industry. Thanks to phase-change materials, we can increase the amount of heat storage. Great thermal inertia of the building provides more stable conditions inside the rooms and allows the use of unconventional sources of energy such as solar energy. A way to reduce the energy consumption of the object is the use of modern solutions for ventilation systems. An example is the solar chimney, which supports natural ventilation in order to improve internal comfort of the rooms. Numerous studies are being carried out in order to determine the optimal construction of solar chimneys in terms of materials and construction parameters. One of the elements of solar chimneys is an absorption plate, which affects the amount of accumulated heat in the construction. In order to carry out the research on the thermal capacity of the absorption plate, the first research work has been already planned. The work presents the research results of a heat-transfer coefficient of the absorption plates samples made of cement, aggregate, water, and phase-change material in different volume percentage. The work also presents methodology and the research process of phase-change material samples.

Design of a natural draft air-cooled condenser and its heat transfer characteristics in the passive residual heat removal system for 10 MW molten salt reactor experiment

International Nuclear Information System (INIS)

Zhao, Hangbin; Yan, Changqi; Sun, Licheng; Zhao, Kaibin; Fa, Dan

2015-01-01

As one of the Generation IV reactors, Molten Salt Reactor (MSR) has its superiorities in satisfying the requirements on safety. In order to improve its inherent safety, a concept of passive residual heat removal system (PRHRS) for the 10 MW Molten Salt Reactor Experiment (MSRE) was put forward, which mainly consisted of a fuel drain tank, a feed water tank and a natural draft air-cooled condenser (NDACC). Besides, several valves and pipes are also included in the PRHRS. A NDACC for the PRHRS was preliminarily designed in this paper, which contained a finned tube bundle and a chimney. The tube bundle was installed at the bottom of the chimney for increasing the velocity of the air across the bundle. The heat transfer characteristics of the NDACC were investigated by developing a model of the PRHRS using C++ code. The effects of the environmental temperature, finned tube number and chimney height on heat removal capacity of the NDACC were analyzed. The results show that it has sufficient heat removal capacity to meet the requirements of the residual heat removal for MSRE. The effects of these three factors are obvious. With the decay heat reducing, the heat dissipation power declines after a short-time rise in the beginning. The operation of the NDACC is completely automatic without the need of any external power, resulting in a high safety and reliability of the reactor, especially once the accident of power lost occurs to the power plant. - Highlights: • A model to study the heat transfer characteristics of the NDACC was developed. • The NDACC had sufficient heat removal capacity to remove the decay heat of MSRE. • NDACC heat dissipation power depends on outside temperature and condenser geometry. • As time grown, the effects of outside temperature and condenser geometry diminish. • The NDACC could automatically adjust its heat removal capacity

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.

Formation of dioxins from incineration of foods found in domestic garbage.

Science.gov (United States)

Katami, Takeo; Yasuhara, Akio; Shibamoto, Takayuki

2004-02-15

There has been great concern about the large amounts of garbage produced by domestic households in the modern world. One of the major sources of dioxins (PCDDs, PCDFs, and coplanar PCBs) in the environment is the combustion of domestic waste materials. Exhaust gases from an incinerator, in which mixtures of 67 food items--including fruits, vegetables, pasta, seafoods, meats, and processed foods and seasoned foods--were analyzed for dioxins. Gases collected at the chimney port (9.15 ng/g) contained less total dioxins than those collected at the chamber port (29.1 ng/g). The levels of Cl1-Cl6-PCDDs and Cl1-Cl5-PCDFs were much lower in the gas collected at the chimney port than in the gas collected at the chamber port. The levels of Cl7-Cl8-PCDDs and Cl6-Cl8-PCDFs were higher in the gas collected at the chimney port than in the gas collected at the chamber port. A total of Cl4-Cl8-PCDDs (1.84-3.04 ng/g) comprised over 80% of the total PCDDs formed (2.24-4.00 ng/g). Total PCDFs (16.2-22.6 ng/g) comprised 78-86% of the total dioxins formed (18.9-29.1 ng/g). The PCDFs formed in the greatest amounts were M1CDFs (9.68-10.7 ng/g). Mixtures of commonly consumed food items produced ppb levels of total dioxins in exhaust gases upon combustion, suggesting that incineration of domestic food wastes is one of the sources of dioxins in the environment. A mixture containing some seasoned foods, such as mayonnaise spread on bread, produced more dioxins (29.1 ng/g) than a mixture without seasoned foods did (18.9 ng/g).

Pito Seamount revisited: the discovery and mapping of new black smoker vents

Science.gov (United States)

Cheadle, M. J.; John, B. E.; German, C. R.; Gee, J. S.; Coogan, L. A.; Gillis, K. M.; Swapp, S.

2017-12-01

In February 2017, the RV Atlantis PMaG (PaleoMagnetism and Gabbro) cruise re-visited a black smoker site originally discovered 24 years ago on Pito Seamount, by the submersible Nautile during the French Pito expedition (1993). Pito Seamount (111.639oW, 23.333oS) marks the northern tip of the propagating East Pacific Rise, bounding the east side of the Easter Microplate. There the seafloor rises to 2250mbsl and has a 900m wide, 50m deep axial valley, which hosts at least two separate fields of active hydrothermal vents. AUV Sentry mapping of the summit of Pito seamount (0.5-1m resolution) highlights over 50 active and inactive chimneys amid recent basaltic sheet flows, pillow mounds and ponded lava. The vents occur in two fields/sub-fields; the first covers an area of 800 x 200m, and lies parallel to the ridge axis, along incipient faults forming on the northeastern flank of the axial valley. The second field occurs in a 250m diameter area in the centre of the axial valley. Jason II dive 961 visited, sampled, measured vent orifice temperatures, and acquired 4k video of the chimneys, and re-discovered the active (Magnificent Village) vent first found by Nautile, in the now named Nautile vent field, together with five additional active hydrothermal vents (Jason, Medea, Sentry, Abe and Scotty's Castle). The Magnificent Village, the largest active vent, is 25m tall and has multiple active spires in three main groups surrounding a hollow amphitheater. Measured vent orifice temperatures ranged from 338oC (Magnificent Village) to 370oC (Jason). The vents host a fauna of alvinellid worms, bythograidid crabs, alvincardid shrimps, phymorhynchus gastropods, Corallimorphid anenomes and bathymodiolid mussels, but no vestimentiferan worms. Brisingid brittle stars colonize inactive chimneys.

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)

Yamaguchi, Akira; Yamamoto, Masahiro; Takai, Ken; Ishii, Takumi; Hashimoto, Kazuhito; Nakamura, Ryuhei

2014-01-01

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 H 2 for CO 2 reduction and carbon assimilation. In addition to the direct reaction of H 2 and CO 2 , the electrical current passing across a bisulfide-bearing chimney structure has pointed to the possible electrocatalytic CO 2 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 CO 2 reduction by iron sulfide (FeS) deposits at slightly acidic pH. Although FeS deposits inefficiently reduced CO 2 , the efficiency of the reaction was substantially improved by the substitution of Fe with Ni to form FeNi 2 S 4 (violarite), of which surface was further modified with amine compounds. The potential-dependent activity of CO 2 reduction demonstrated that CO 2 reduction by H 2 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, H 2 generation competes with CO 2 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 H 2 generation

Investigating atrium in hot and humid climate and providing ...

African Journals Online (AJOL)

Atrium has thermal comfort space since the old time by two methods of greenhouse effect and chimney effect. Now these questions are raised: What impact does atrium have in terms of performance in reducing energy consumption in buildings and how is the performance of atrium in the hot and humid climate, and how it ...

HRR Upgrade to mass loss calorimeter and modified Schlyter test for FR Wood

Science.gov (United States)

Mark A. Dietenberger; Charles R. Boardman

2013-01-01

Enhanced Heat Release Rate (HRR) methodology has been extended to the Mass Loss Calorimeter (MLC) and the Modified Schlyter flame spread test to evaluate fire retardant effectiveness used on wood based materials. Modifications to MLC include installation of thermopile on the chimney walls to correct systematic errors to the sensible HRR calculations to account for...

Cultural Resources Reconnaissance Study of the Black Warrior-Tombigbee System Corridor, Alabama. Volume 2. Ethnohistory. A Documentary Study of Native American Life in the Lower Tombigbee Valley.

Science.gov (United States)

1983-01-01

they had prepared the skins. They were roasting meat and fish on the fire. The description is vague, and it is unclear whether they were using the...chimney, with a gallery at one gable; there was also a chicken house, and to the right of the (courtyard) a large structure sixty by thirteen feet

EXPERIMENTAL STUDY IN NATURAL CONVECTION

African Journals Online (AJOL)

PROF. BARTH EKWEME

The study of thermal and ventilation parameters, obtained in a transient, laminar solar chimney of reduced dimensions, (1 < m <3) m with a square collector (side = 2m) is presented. Experimental measurements has been made to determine the temperature of the absorber and the fluid in the collector, it is shown that at the ...

Technical considerations for Plowshare applications to oil shale

Energy Technology Data Exchange (ETDEWEB)

Lombard, David B [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States); Bray, Bruce G [CER Geonuclear Corporation, Las Vegas, NV (United States); Sohns, Harold W [U. S. Bureau of Mines, Laramie, WY (United States)

1970-05-15

Nuclear explosions have been proposed for use in the recovery of oil from deep oil shale deposits. Before commercial feasibility can be established, a variety of technical problems must be examined. Some of these are related to nuclear explosion effects, others to the recovery of oil from the broken rock. Among the primary areas of interest are fracturing, chimney collapse, rubble size distribution, radioactivity, and retorting methods and variables. To test the concept, nuclear explosion experiments will be needed. One such experiment. Project Bronco, has been designed in detail, and is used here to illustrate a possible direction of development. The design is based on the following objectives: to evaluate the overall feasibility of nuclear breaking, followed by in situ retorting; to investigate the gross physical effects of a nuclear explosion in oil shale, and to assess the role of radioactivities in the production of oil by in situ retorting. The experimental plan provides for the accomplishment of these objectives by appropriate preshot studies, a postshot examination of explosion effects, and experimental retorting of the nuclear chimney. (author)

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 (serpentinization reactions of the ultramafic basement into the lagoon seawater. They are responsible for the formation of carbonate chimneys at the lagoon seafloor. Capillary electrophoresis single-strand conformation polymorphism fingerprinting, quantitative polymerase chain reaction and sequence analysis of 16S rRNA genes revealed changes in 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.

How Termite Mounds Breath?

Science.gov (United States)

Saxena, Saurabh; Yaghoobian, Neda

2017-11-01

Fungus-cultivating termites of the subfamily Macrotermitinae that are extensively found throughout sub-Saharan Africa and south East Asia are one species of termites that collectively build massive, uninhabited, complex structures. These structures, which are much larger than the size of an individual termite, effectively use natural wind and solar energies and the energy embodied in colony's metabolic activity to maintain the necessary condition for termite survival. These mounds enclose a subterranean nest, where the termite live and cultivate fungus, as well as a complex network of tunnels consisting of a large, vertically oriented central chimney, surface conduits, and lateral connectives that connect the chimney and the surface conduits. In this study, we use computational modeling to explore the combined interaction of geometry, heterogeneous thermal mass, and porosity with the external turbulent wind and solar radiation to investigate the physical principles and fundamental aero-thermodynamics underlying the controlled and stable climate of termite mounds. Exploitation of natural resources of wind and solar energies in these natural systems for the purpose of ventilation will lead to new lessons for improving human habitats conditions.

Genetic modification of the effect of maternal household air pollution exposure on birth weight in Guatemalan newborns.

Science.gov (United States)

Thompson, Lisa M; Yousefi, Paul; Peñaloza, Reneé; Balmes, John; Holland, Nina

2014-12-01

Low birth weight is associated with exposure to air pollution during pregnancy. The purpose of this study was to evaluate whether null polymorphisms of Glutathione S-transferases (GSTs), specifically GSTM1 and GSTT1 genes in infants or mothers, modify the association between high exposures to household air pollution (HAP) from cooking fires and birth weight. Pregnant women in rural Guatemala were randomized to receive a chimney stove or continue to use open fires for cooking. Newborns were measured within 48 h of birth. 132 mother-infant pairs provided infant genotypes (n=130) and/or maternal genotypes (n=116). Maternal null GSTM1 was associated with a 144 g (95% CI, -291, 1) and combined maternal/infant null GSTT1 was associated with a 155 g (95% CI, -303, -8) decrease in birth weight. Although there was a trend toward higher birth weights with increasing number of expressed GST genes, the effect modification by chimney stove use was not demonstrated. Copyright © 2014 Elsevier Inc. All rights reserved.

Technical considerations for Plowshare applications to oil shale

International Nuclear Information System (INIS)

Lombard, David B.; Bray, Bruce G.; Sohns, Harold W.

1970-01-01

Nuclear explosions have been proposed for use in the recovery of oil from deep oil shale deposits. Before commercial feasibility can be established, a variety of technical problems must be examined. Some of these are related to nuclear explosion effects, others to the recovery of oil from the broken rock. Among the primary areas of interest are fracturing, chimney collapse, rubble size distribution, radioactivity, and retorting methods and variables. To test the concept, nuclear explosion experiments will be needed. One such experiment. Project Bronco, has been designed in detail, and is used here to illustrate a possible direction of development. The design is based on the following objectives: to evaluate the overall feasibility of nuclear breaking, followed by in situ retorting; to investigate the gross physical effects of a nuclear explosion in oil shale, and to assess the role of radioactivities in the production of oil by in situ retorting. The experimental plan provides for the accomplishment of these objectives by appropriate preshot studies, a postshot examination of explosion effects, and experimental retorting of the nuclear chimney. (author)

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

EEA'S management policy for better environmental performance

International Nuclear Information System (INIS)

Awad, M.M.; Yassin, L.; Khashab, A.M.; Bedrous, M.A.

1999-01-01

The supply and use of electric energy has both positive and impacts.pollution is the principal negative aspect with local effects, such as the particulates from power plant chimneys; regional effects such as acid rain; and global effects, of which the main one could be the effect of greenhouse gases such as carbon dioxide and methane on climate

Research programme related to the influence of wind on contamination containment in nuclear installations

Energy Technology Data Exchange (ETDEWEB)

Soares, S.; Gelain, T.; Laborde, J.C.; Ricciardi, L. [Institut de Radioprotection et de Surete Nucleaire (IRSN/DSU/SERAC/LEMAC), 91 - Gif-sur-Yvette (France)

2006-07-01

In nuclear industry, the response of a ventilation network to accidental disturbances, either mechanical (fan failure, damper blockage,..) or thermal (fire..) is difficult to evaluate when the network becomes complex. In order to determine and analyze the consequences of these disturbances on the radioactive materials containment, a computer code called SIMEVENT has been developed. However, among the external parameters likely to affect a ventilation network, the wind effect is actually basically modeled, due to a lack of qualified data concerning the wind impact on complex building geometries and the interaction between wind and chimney exhaust. In view of the networks complexity and the facilities diversity, a research program including experimental and model studies has been launched to assess the wind influence on contamination containment. 1. step: improvement of data (2005-2006): The diversity of facilities geometries needs the use of a qualified multi-D code for pressure coefficients Cpi assessment, characterizing the wind effect on building walls and the interaction between wind and chimney exhaust. Different chimney terminals have then been placed in a wind tunnel (the parameters are the incline angle a, the wind velocity U and the air flow in the duct W); for each angle, the evolution of the pressure coefficient versus wind velocity is determined and is characteristic of a chimney terminal geometry. Furthermore, two types of scale-model have been chosen for representing either nuclear power plants (NPP) or plants and laboratories buildings. The different values of wind pressure coefficients have been measured on both scale-models placed in a wind-tunnel. The experimental data obtained are compared with CFD simulations (CFX code), in order to qualify such code for the assessment of pressure coefficient on complex geometries. The results are quite encouraging. 2. step - wind tunnel tests on a ventilated scale model (2007-2009): Wind tunnel tests will be

Research programme related to the influence of wind on contamination containment in nuclear installations

International Nuclear Information System (INIS)

Soares, S.; Gelain, T.; Laborde, J.C.; Ricciardi, L.

2006-01-01

In nuclear industry, the response of a ventilation network to accidental disturbances, either mechanical (fan failure, damper blockage,..) or thermal (fire..) is difficult to evaluate when the network becomes complex. In order to determine and analyze the consequences of these disturbances on the radioactive materials containment, a computer code called SIMEVENT has been developed. However, among the external parameters likely to affect a ventilation network, the wind effect is actually basically modeled, due to a lack of qualified data concerning the wind impact on complex building geometries and the interaction between wind and chimney exhaust. In view of the networks complexity and the facilities diversity, a research program including experimental and model studies has been launched to assess the wind influence on contamination containment. 1. step: improvement of data (2005-2006): The diversity of facilities geometries needs the use of a qualified multi-D code for pressure coefficients Cpi assessment, characterizing the wind effect on building walls and the interaction between wind and chimney exhaust. Different chimney terminals have then been placed in a wind tunnel (the parameters are the incline angle a, the wind velocity U and the air flow in the duct W); for each angle, the evolution of the pressure coefficient versus wind velocity is determined and is characteristic of a chimney terminal geometry. Furthermore, two types of scale-model have been chosen for representing either nuclear power plants (NPP) or plants and laboratories buildings. The different values of wind pressure coefficients have been measured on both scale-models placed in a wind-tunnel. The experimental data obtained are compared with CFD simulations (CFX code), in order to qualify such code for the assessment of pressure coefficient on complex geometries. The results are quite encouraging. 2. step - wind tunnel tests on a ventilated scale model (2007-2009): Wind tunnel tests will be

77 FR 59275 - Establishment of the Chimney Rock National Monument

Science.gov (United States)

2012-09-27

..., political, and religious interdependence centered in Chaco Canyon, New Mexico, about 100 miles south of... areas near and far, these lands support a growing travel and tourism sector that is a source of economic...

Of Dutch courage and mobile chimneys: Pattern and predictors of ...

African Journals Online (AJOL)

Previous studies in Nigeria have associated alcohol and tobacco use among students with certain socioeconomic and educational achievement variables, albeit its determinants among university students remain largely unknown. This study examined current patterns and predictors of alcohol and tobacco use with a model ...

Use of satellite information for analysis of aerosol substance propagation

Science.gov (United States)

Lezhenin, A. A.; Raputa, V. F.; Yaroslavtseva, T. V.

2015-11-01

With satellite data on pollution of snow cover and data of meteorological observations, some fields of dust sedimentation from high chimneys of the Iskitim cement plant are studied. In the absence of snowfalls, a possibility to analyze of the areas of pollution, which are formed in time intervals from several days to several weeks in the vicinities of industrial enterprises, is shown.

Improvements in or relating to handling of flue gas

International Nuclear Information System (INIS)

Ingham, R.V.

1986-01-01

The patent describes improvements in the method for handling flue gas from the burning of fossil fuels. The method relates to cleaning the flue gas, from which the sulphur compounds are removed. The gas in then heated by heat derived from a nuclear source, which may be nuclear waste. The heat treatment gives efficient atmospheric dispersion from the chimney. (U.K.)

Natural gas production from underground nuclear explosions

Energy Technology Data Exchange (ETDEWEB)

1965-01-01

A remote location in Rio Arriba County, NW. New Mexico, is being considered as the site for an experiment in the use of a nuclear explosive to increase production from a natural gas field. A feasibility study has been conducted by the El Paso Natural Gas Co., the U.S. Atomic Energy commission, and the U.S. Bureau of Mines. As presently conceived, a nuclear explosive would be set in an emplacement hole and detonated. The explosion would create a cylinder or ''chimney'' of collapsed rock, and a network of fractures extending beyond the chimney. The fractures are the key effect. These would consist of new fractures, enlargement of existing ones, and movement along planes where strata overlap. In addition, there are a number of intangible but important benefits that could accrue from the stimulating effect. Among these are the great increase in recoverable reserves and the deliverability of large volumes of gas during the periods of high demand. It is believed that this type of well stimulation may increase the total gas production of these low permeability natural gas fields by about 7 times the amounts now attainable.

SImulated Dodewaard ASsembly: Developments in loop-design

International Nuclear Information System (INIS)

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.)

Sustainable wood use, decarbonisation of energetic metabolism and forest development

DEFF Research Database (Denmark)

Czeskleba-Dupont, Rolf

2009-01-01

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......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...... of energy, when substituting for fossil fuels, whereas compensatory binding of carbon dioxide by tree growth over many decades is referred to an insecure future under global warming. Harvested wood products should rather not be used in atmospheric burners, but in product form. Otherwise an accelerated...

Emergency automatic commutation of the ventilation system of the RP-10 nuclear reactor

International Nuclear Information System (INIS)

Castillo, Walter; Corimanya, Mario; Ovalle, Edgar; Anaya, Olgger; Veramendi, Emilio

2013-01-01

The present paper summarizes the achievements in the design and implementation of a system for monitoring and automatic control of radioactive effluents from the chimney of the RP-10 reactor, using as hardware an Arduino UNO platform containing an ATMEGA 328 programmable micro controller to which has been added LCD screen to display the values, a keyboard and an EEPROM memory data, where the limit of the level of radiation is fixed. The radiation level in the air of the reactor hall, going up the chimney is counted by a radiation monitor called MAB1000, and data are supplied to the new system. When the radiation level is above the national and international standards, the new design makes work a relay, so that the ventilation system is automatically switched to operate in emergency condition, preventing the release of radioactive contaminants into the environment. After installing the new design, it was verified that removed by the radiation monitor MAB1000, value is identical to that shown in the new system. Additionally, the operation of the relay was tested successfully with radioactive sources to switch the ventilation system to the emergency condition. (authors).

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.).

Study on the alternative mitigation of cement dust spread by capturing the dust with fogging method

Science.gov (United States)

Purwanta, Jaka; Marnoto, Tjukup; Setyono, Prabang; Handono Ramelan, Ari

2017-12-01

The existence of a cement plant impact the lives of people around the factory site. For example the air quality, which is polluted by dust. Cement plant has made various efforts to mitigate the generated dust, but there are still alot of dust fly inground either from the cement factory chimneys or transportation. The purpose of this study was to conduct a review of alternative mitigation of the spread of dust around the cement plant. This study uses research methods such as collecting secondary data which includes data of rain density, the average rains duration, wind speed and direction as well as data of dust intensity quality around PT. Semen Gresik (Persero) Tbk.Tuban plant. A soft Wind rose file is used To determine the wind direction propensity models. The impact on the spread of dust into the environment is determined using secondary data monitoring air quality. Results of the study is that the mitigation of dust around the cement plant is influenced by natural factors, such as the tendency of wind direction, rain fall and rainy days, and the rate of dust emission from the chimney. The alternative means proposed is an environmental friendly fogging dust catcher.

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.

Emergency automatic commutation of the ventilation system of the RP-10 nuclear reactor; Conmutacion automatica de emergencia del sistema de ventilacion del reactor nuclear RP-10

Energy Technology Data Exchange (ETDEWEB)

Castillo, Walter; Corimanya, Mario; Ovalle, Edgar; Anaya, Olgger; Veramendi, Emilio [Direccion de Produccion, Instituto Peruano de Energia Nuclear, Av. Jose Saco km 12.5, Carabayllo, Lima (Peru)

2013-07-01

The present paper summarizes the achievements in the design and implementation of a system for monitoring and automatic control of radioactive effluents from the chimney of the RP-10 reactor, using as hardware an Arduino UNO platform containing an ATMEGA 328 programmable micro controller to which has been added LCD screen to display the values, a keyboard and an EEPROM memory data, where the limit of the level of radiation is fixed. The radiation level in the air of the reactor hall, going up the chimney is counted by a radiation monitor called MAB1000, and data are supplied to the new system. When the radiation level is above the national and international standards, the new design makes work a relay, so that the ventilation system is automatically switched to operate in emergency condition, preventing the release of radioactive contaminants into the environment. After installing the new design, it was verified that removed by the radiation monitor MAB1000, value is identical to that shown in the new system. Additionally, the operation of the relay was tested successfully with radioactive sources to switch the ventilation system to the emergency condition. (authors).

Applicability of best-estimate analysis TRACE in terms of natural circulation BWR stability

International Nuclear Information System (INIS)

Furuya, Masahiro; Ueda, Nobuyuki; Nishi, Yoshihisa

2011-01-01

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)

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.

Application of Crunch-Flow Routines to Constrain Present and Past Carbon Fluxes at Gas-Hydrate Bearing Sites

Energy Technology Data Exchange (ETDEWEB)

Torres, Marta [Oregon State Univ., Corvallis, OR (United States). College of Earth, Ocean, and Atmospheric Sciences

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

Sustained in situ measurements of dissolved oxygen, methane and water transport processes in the benthic boundary layer at MC118, northern Gulf of Mexico

Science.gov (United States)

Martens, Christopher S.; Mendlovitz, Howard P.; Seim, Harvey; Lapham, Laura; D'Emidio, Marco

2016-07-01

Within months of the BP Macondo Wellhead blowout, elevated methane concentrations within the water column revealed a significant retention of light hydrocarbons in deep waters plus corresponding dissolved oxygen (DO) deficits. However, chemical plume tracking efforts were hindered by a lack of in situ monitoring capabilities. Here, we describe results from in situ time-series, lander-based investigations of physical and biogeochemical processes controlling dissolved oxygen, and methane at Mississippi Canyon lease block 118 ( 18 km from the oil spill) conducted shortly after the blowout through April 2012. Multiple sensor arrays plus open-cylinder flux chambers (;chimneys;) deployed from a benthic lander collected oxygen, methane, pressure, and current speed and direction data within one meter of the seafloor. The ROVARD lander system was deployed for an initial 21-day test experiment (9/13/2010-10/04/2010) at 882 m depth before a longer 160-day deployment (10/24/2011-4/01/2012) at 884 m depth. Temporal variability in current directions and velocities and water temperatures revealed strong influences of bathymetrically steered currents and overlying along-shelf flows on local and regional water transport processes. DO concentrations and temperature were inversely correlated as a result of water mass mixing processes. Flux chamber measurements during the 160-day deployment revealed total oxygen utilization (TOU) averaging 11.6 mmol/m2 day. Chimney DO concentrations measured during the 21-day deployment exhibited quasi-daily variations apparently resulting from an interaction between near inertial waves and the steep topography of an elevated scarp immediately adjacent to the 21-day deployment site that modulated currents at the top of the chimney. Variability in dissolved methane concentrations suggested significant temporal variability in gas release from nearby hydrocarbon seeps and/or delivery by local water transport processes. Free-vehicle (lander) monitoring

Preliminary Results on Mineralogy and Geochemistry of Loki's Castle Arctic Vents and Host Sediments

Science.gov (United States)

Barriga, Fernando; Carvalho, Carlos; Inês Cruz, M.; Dias, Ágata; Fonseca, Rita; Relvas, Jorge; Pedersen, Rolf

2010-05-01

The Loki's Castle hydrothermal vent field was discovered in the summer of 2008, during a cruise led by the Centre of Geobiology of the University of Bergen, integrated in the H2Deep Project (Eurocores, ESF). Loki's Castle is the northernmost hydrothermal vent field discovered to date. It is located at the junction between the Mohns Ridge and the South Knipovich Ridge, in the Norwegian-Greenland Sea, at almost 74°N. This junction shows unique features and apparently there is no transform fault to accommodate the deformation generated by the bending of the rift valley from WSW-ENE to almost N-S. The Knipovich Rigde, being a complex structure, is an ultra-slow spreading ridge, with an effective spreading rate of only ~ 6 mm/y. It is partly masked by a substantial cover of glacial and post-glacial sediments, estimated to be between 12 and 20 ky old, derived from the nearby Bear Island fan, to the East of the ridge. The Loki's Castle vent site is composed of several active, over 10 m tall chimneys, producing up to 320°C fluid, at the top of a very large sulphide mound, which is estimated to be around 200 m in diameter. About a dozen gravity cores were obtained in the overall area. From these we collected nearly 200 subsamples. Eh and pH were measured in all subsamples. The Portuguese component of the H2Deep project is aimed at characterizing, chemically and mineralogically, the sulphide chimneys and the collected sediments around the vents (up to 5 meters long gravity cores). These studies are aimed at understanding the ore-forming system, and its implications for submarine mineral exploration, as well as the relation of the microbial population with the hydrothermal component of sediments. Here we present an overview of preliminary data on the mineralogical assemblage found in the analyzed sediments and chimneys. The identification of the different mineral phases was obtained through petrographic observations of polished thin sections under the microscope (with both

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

2016-09-12

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.

Gasbuggy reservoir evaluation - 1969 report

International Nuclear Information System (INIS)

Atkinson, C.H.; Ward, Don C.; Lemon, R.F.

1970-01-01

The December 10, 1967, Project Gasbuggy nuclear detonation followed the drilling and testing of two exploratory wells which confirmed reservoir characteristics and suitability of the site. Reentry and gas production testing of the explosive emplacement hole indicated a collapse chimney about 150 feet in diameter extending from the 4,240-foot detonation depth to about 3,900 feet, the top of the 300-foot-thick Pictured Cliffs gas sand. Production tests of the chimney well in the summer of 1968 and during the last 12 months have resulted in a cumulative production of 213 million cubic feet of hydrocarbons, and gas recovery in 20 years is estimated to be 900 million cubic feet, which would be an increase by a factor of at least 5 over estimated recovery from conventional field wells in this low permeability area. At the end of production tests the flow rate was 160,000 cubic feet per day, which is 6 to 7 times that of an average field well in the area. Data from reentry of a pre-shot test well and a new postshot well at distances from the detonation of 300 and 250 feet, respectively, indicate low productivity and consequently low permeability in any fractures at these locations. (author)

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.

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.

Determination of the origins of pollution by activation analysis

International Nuclear Information System (INIS)

Shibuya, Masao

1974-01-01

An example of the detection of the origin of pollution is given. In the autumn of 1972, black spots appeared on the leaves and rind of tangerine in K prefecture, which is famous for the production of tangerine. The spots appeared on the surface of the rind of tangerine lowered the commercial value. The examination on the black spots with an x-ray microprobe analyzer indicated that the sulfur was present in high concentration in the spots. Moreover, the sulfur was not distributed uniformly, but was present as minute aggregations in the spots. This finding shows that the cause of the black spots is sulfur. Also, it was found that the sulfur must be mist or dust. Otherwise, the sulfur distribution in the spots must be uniform. The chimneys belonged to two different factories were suspicious. Therefore, the identification of the origin of the mist or dust was made next. Vanadium was detected in the black spots, but not in other places of plants. The chimney of one factory kept a large amount of vanadium in the dust in the flue, but the other did not. Thus the identification of the origin of the pollution was exactly made. (Fukutomi, T.)

Enhancing load-following and/or spectral shift capability in single-sparger natural circulation boiling water reactors

International Nuclear Information System (INIS)

Oosterkamp, W.J.

1992-01-01

This patent describes a method for obtaining load-following capability in a coiling water reactor (BWR) wherein housed within a reactor pressure vessel (RPV) is a nuclear core disposed within a shroud having a shroud head and which with the RPV defines an annulus region disposed beneath the nuclear core, an upper steam dome connected to a steam outlet in the RPV, a core upper plenum formed within the shroud head and disposed atop the nuclear core, a chimney mounted atop the shroud head and in fluid communication with the core upper plenum and with a steam separator having a skirt which is in fluid communication with the steam dome, the region outside of the chimney defining a downcomer region, there being a water level established therein under normal operation of the BWR, and the RPV containing a feedwater inlet. It comprises: disposing a single sparger connected to the feedwater inlet above the steam separator skirt bottom about the interior circumference of the RPV at an elevation at approximately the water level established during normal operation of the BWR; and adjusting the feedwater flow through the inlet and into the sparger to vary the water level to be above, at or below the elevational location of the sparger in response to load-following need

Termite mounds harness diurnal temperature oscillations for ventilation.

Science.gov (United States)

King, Hunter; Ocko, Samuel; Mahadevan, L

2015-09-15

Many species of millimetric fungus-harvesting termites collectively build uninhabited, massive mound structures enclosing a network of broad tunnels that protrude from the ground meters above their subterranean nests. It is widely accepted that the purpose of these mounds is to give the colony a controlled microclimate in which to raise fungus and brood by managing heat, humidity, and respiratory gas exchange. Although different hypotheses such as steady and fluctuating external wind and internal metabolic heating have been proposed for ventilating the mound, the absence of direct in situ measurement of internal air flows has precluded a definitive mechanism for this critical physiological function. By measuring diurnal variations in flow through the surface conduits of the mounds of the species Odontotermes obesus, we show that a simple combination of geometry, heterogeneous thermal mass, and porosity allows the mounds to use diurnal ambient temperature oscillations for ventilation. In particular, the thin outer flutelike conduits heat up rapidly during the day relative to the deeper chimneys, pushing air up the flutes and down the chimney in a closed convection cell, with the converse situation at night. These cyclic flows in the mound flush out CO2 from the nest and ventilate the colony, in an unusual example of deriving useful work from thermal oscillations.

Gasbuggy reservoir evaluation - 1969 report

Energy Technology Data Exchange (ETDEWEB)

Atkinson, C H; Ward, Don C [Bureau of Mines, U.S. Department of the Interior (United States); Lemon, R F [El Paso Natural Gas Company (United States)

1970-05-01

The December 10, 1967, Project Gasbuggy nuclear detonation followed the drilling and testing of two exploratory wells which confirmed reservoir characteristics and suitability of the site. Reentry and gas production testing of the explosive emplacement hole indicated a collapse chimney about 150 feet in diameter extending from the 4,240-foot detonation depth to about 3,900 feet, the top of the 300-foot-thick Pictured Cliffs gas sand. Production tests of the chimney well in the summer of 1968 and during the last 12 months have resulted in a cumulative production of 213 million cubic feet of hydrocarbons, and gas recovery in 20 years is estimated to be 900 million cubic feet, which would be an increase by a factor of at least 5 over estimated recovery from conventional field wells in this low permeability area. At the end of production tests the flow rate was 160,000 cubic feet per day, which is 6 to 7 times that of an average field well in the area. Data from reentry of a pre-shot test well and a new postshot well at distances from the detonation of 300 and 250 feet, respectively, indicate low productivity and consequently low permeability in any fractures at these locations. (author)

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)

Analysis of Irradiation Holes of In-Core Region

Energy Technology Data Exchange (ETDEWEB)

In, Won-ho; Lee, Yong-sub; Kim, Tae-hwan; Lim, Kyoung-hwan; Ahn, Hyung-jin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-05-15

Test fuels and materials are irradiated in the in-core region in side of the chimney. The inner chimney is composed of In-Core and Out-Core regions. The In-Core region has 23 hexagonal vertical irradiation holes named from R01 to R20, CT, IR1 and IR2 and 8 cylindrical irradiation holes named from CAR1 to CAR4 and SOR1 to SOR4. The Out-Core region is composed of 8 cylindrical irradiation holes named from OR1 to OR8 which are installed near the inner shell of the reflector tank. HANARO is the multi-purpose research reactor which utilizes in-core irradiation holes, which is being used in various field. Over the past 7 years we have used CT 8 times, IR once, IR2 and OR3 twice, OR4 three times and OR5 ten times. These irradiation holes are used to perform an evaluation of the neutron irradiation properties and the tests were all completed and done successfully. HANARO has been used successfully, and it still will be used continuously in various fields such as nuclear in-pile tests, the production of radioisotopes, neutron transmutation doping, neutron activation analysis, neutron beam research, radiography, environmental science.

Engineering safety features for high power experimental reactors

International Nuclear Information System (INIS)

Doval, A.; Villarino, E.; Vertullo, A.

2000-01-01

In the present analysis we will focus our attention in the way engineering safety features are designed in order to prevent fuel damage in case of abnormal or accidental situations. To prevent fuel damage two main facts must be considered, the shutdown of the reactor and the adequate core cooling capacity, it means that both, neutronic and thermohydraulic aspects must be analysed. Some neutronic safety features are common to all power ranges like negative feedback reactivity coefficients and the required number of control rods containing the proper absorber material to shutdown the reactor. From the thermohydraulic point of view common features are siphon-breaker devices and flap valves for those powers requiring cooling in the forced convection regime. For the high power reactor group, the engineering safety features specially designed for a generic reactor of 20 MW, will be presented here. From the neutronic point of view besides the common features, and to comply with our National Regulatory Authority, a Second Shutdown System was designed as a redundant shutdown system in case the control plates fail. Concerning thermohydraulic aspects besides the pump flywheels and the flap valves providing the natural convection loop, a metallic Chimney and a Chimney Water Injection System were supplied. (author)

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.

Arsenic speciation in food chains from mid-Atlantic hydrothermal vents.

Science.gov (United States)

Taylor, Vivien F; Jackson, Brian P; Siegfried, Matthew; Navratilova, Jana; Francesconi, Kevin A; Kirshtein, Julie; Voytek, Mary

2012-05-04

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 (δ 13 C and δ 15 N) 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 food web without algae or other photosynthetic life.

For the Record - A History of the Nuclear Test Personnel Review Program, 1978-1986.

Science.gov (United States)

1986-08-01

expanding umbrella overhead ... For minutes the cloud stood solid and impressive, like some gigantic monument, over Bikini. Then finally the shearing of the...from all parts of the target fleet at once. A gigantic flash -- then it was gone. And where it had been now stood a white chimney of water * reaching...the bone/ joints, soft tissue, endocrine system, or multiple myeloma were found. With regard to mortality, the cohort had considerably fewer total

Chapter 2: Development of instrumentation for safety analyses in fuel reprocessing and treatment plants

International Nuclear Information System (INIS)

Anon.

1985-01-01

Development and provision of methods allowing for safety-related statements on non-appropriate operation of intermediate storage, reprocessing and waste conditioning on the basis of probabilities. By applying the methods and models to the courses of events considered, activity releases at the chimney and their probable frequency were determined. For accidents known to be radiologically relevant, expected values for exposure were computed by means of complex distribution and exposure models. (DG) [de

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)

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.)

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...

The model for calculation of emission and imisson of air pollutants from vehicles with internal combustion engine

International Nuclear Information System (INIS)

Tashevski, Done; Dimitrovski, Mile

1994-01-01

The model for calculation of emission and immision of air pollutants from vehicles with internal combustion engine on the crossroads in urban environments, with substitution of a great number of exhaust-pipes with one chimney in the centre of the crossroad has been made. The whole calculation of the pollution sources mentioned above is, in the fact, the calculation of the emission and imisson of pollutants from point sources of pollution. (author)

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

Mineralogy and Acid-Extractable Geochemistry from the Loki's Castle Hydrothermal Field, Norwegian Sea at 74 degrees N (South Knipovich Ridge)

Science.gov (United States)

Barriga, F. J.; Fonseca, R.; Dias, S.; Cruz, I.; Carvalho, C.; Relvas, J. M.; Pedersen, R.

2010-12-01

The Loki’s Castle hydrothermal vent field was discovered in the summer of 2008 during a cruise led by the Centre of Geobiology of the University of Bergen, integrated in the H2Deep Project (Eurocores, ESF; see Pedersen et al., 2010, AGU Fall Meeting, Session OS26). Fresh volcanic glasses analyzed by EPMA are basalts. The vent site is composed of several active, over 10 m tall chimneys, producing up to 320 C fluid, at the top of a very large sulfide mound (estimated diameter 200 m). Mineralogy: The main sulfide assemblage in chimneys consists of sphalerite (Sp), pyrite (Py) and pyrrhotite, with lesser chalcopyrite (Ccp). Sulphide-poor selected samples collected at the base of chimneys are mostly composed of anhydrite (Anh), gypsum and talc (Tlc). Association of quartz, anhydrite, gypsum and barite were also found in some of the samples. The sulphide-poor samples from the base of the chimneys denote seawater interaction with the hydrothermal fluid and consequent decrease in temperature, precipitating sulfates. Sphalerite compositions are Zn(0.61-0.70)Fe(0.39-0.30)S. The variations in Fe content are consistent with those of hot, reduced hydrothermal fluids. The observed sulfide assemblage is consistent with the temperature of 320C measured in Loki’s Castle vents. Compositional zonation in sphalerites suggests different pulses of activity of the hydrothermal system, with higher contents of Zn in the center of the crystals. Geochemistry: Here we report preliminary data part of a major analytical task of sequential extraction of metals from sediments in the vicinity of Loki’s Castle, in an attempt to detect correlations with microbial populations and/or subseafloor mineralized intervals. The abundances of Cu, Pb, Ni, Cr, Zn, Fe, Mn and Co in sediments were determined by aqua regia extraction on subsamples from 7 gravity cores. Several anomalous intervals were sampled, in which Cu<707ppm, Ni shows many weak peaks (<50ppm), Cr shows 6 peaks (<121ppm), Zn shows 4 well

New insights into the ground thermal regime of talus slopes with permafrost below the timberline

Science.gov (United States)

Schwindt, Daniel; Kneisel, Christof

2013-04-01

In the central Alps permafrost can be expected above 2400 m a.s.l., at altitudes where mean annual air temperatures are below -1° C. However, isolated permafrost occurrences are present in north-exposed talus slopes, far below the timberline, where mean annual air temperatures are positive. Driving factors are assumed to be a low income of solar radiation, a thick organic layer with high insulation capacities as well as the thermally induced chimney effect (Wakonigg, 1996). Investigated are three talus slopes with permafrost in the Swiss Alps that differ with regard to elevation level, talus material, humus characteristics and vegetation composition as well as the mean annual air temperatures. Aim is to achieve a deeper understanding of the factors determining the site-specific thermal regime, as well as the spatially limited and temporally highly variable permafrost occurrences in vegetated talus slopes. Focus is not solely on the question of why permafrost exists at these sites, but also why permafrost does not exist in the immediate surroundings. To detect the temporal variability and spatial heterogeneity of the permafrost occurrences, electrical resistivity tomography monitoring, seismic refraction tomography monitoring, and quasi-3D ERT were applied. To determine the ground thermal regime, air-, ground surface-, and humus temperatures, as well as temperatures within vents of the chimneys were recorded. Furthermore, humus characteristics (thickness, -temperature and -moisture) were mapped in permafrost-affected slope areas and in the immediate surroundings. To test the correlation between solar radiation, permafrost distribution, and humus/vegetation composition, digital elevation models were used to calculate the income of solar radiation. The areal extent of the permafrost bodies coincide precisely with slope sections where the organic layer is thickest, a consistent moss cover is present, and where temperatures at the transition between humus layer and

Insights into fluid flow and environmental conditions present in deep-sea hydrothermal vent deposits from measurements of permeability and porosity

Science.gov (United States)

Gribbin, J. L.; Zhu, W.; Tivey, M. K.

2008-12-01

Evolution of permeability-porosity relationships (EPPRs) of different seafloor vent deposit sample types provide crucial information about how fluid flows within the deposits. In this study, we conducted permeability and porosity measurements on a wide range of vent sample types recovered from many different active seafloor vent fields. The sample set includes chalcopyrite-lined black smoker chimneys, Zn-rich diffusing spires (including white smokers), flanges/slabs/crusts (i.e., plate-like deposits that overlie pooled fluid), massive anhydrite, and cores recovered from the sides of vent structures. Using a probe permeameter, permeability measurements were systematically taken of each sample along several orientations. The measured permeability ranges over 6 orders of magnitude from 10-14 to 10-8 m2. Our data indicate that in general massive anhydrite samples are the least permeable with a mean at ~10-13 m2 and the samples from Zn-rich diffusing spires that were actively venting when collected are the most permeable with a mean at ~10-11 m2. With a mean at 10-11.5 m2, permeability data of flanges/slabs/crusts span over 4 orders of magnitude from 10-13 to 10-9 m2, the largest spread among all sample types tested. Permeability values of the outer portions of relict spires, ranging from ~10-13 m2 to 10-9.5 m2, displayed clear anisotropic trends: permeability along the radial directions is higher than that along the axial direction. Black smokers exhibit a strong layered heterogeneity, where inner chalcopyrite linings were significantly less permeable than outermost layers. To conduct porosity and directional permeability measurements, cylindrical cores will be taken from these vent samples. We will examine whether different sample types, or portions of samples, exhibit distinct permeability-porosity relationships, and will then use micro-structural observations of the cores to examine chimney growth processes (e.g., mineral deposition or cracking) that likely result

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

The Sutton (13MA266) Site and the Townsites of Percy (13MA347) and Dunreath (13MA449): Data Recovery at Three Historic Sites, Lake Red Rock, Iowa

Science.gov (United States)

1989-07-01

farm also is done by truck chiefly by common carriers although much milk and cream ;s hauled by contract haulers. The development of Marion County...chimney, and a whole medicine bottle. The latter had an improved tooled cork closure and was embossed with the following: I Chamberlain’s/ Colic Cholera...merchants did become actively involved in the truck shipment of eggs, butter, and cream to Des Moines. In later years all the store supplies were brought

Process of coking or distilling fuels, bituminous shale, and the like

Energy Technology Data Exchange (ETDEWEB)

Jurgensen, R

1892-03-17

The charge present in a chamber is exposed without changes to stepwise higher temperatures. This is accomplished so that only a few chambers whose contents are almost finished are heated by generator gas. The distillation products of these chambers go through the charge of the following chambers and carry out carbonization products, which are given for the most part by passage through the following chambers to the colder charge in condensed form, whereby the gases escape out the chimney.

Evaluation of Corrosion Caused by the use of In Natura Biogas in Steam Generator Boilers of Carbon Steel Structural Elements

OpenAIRE

Fontenelle, Marcellus; Alves, Helton José; Monteiro, Marcos Roberto; Higa, Silvia Midori; Rovere, Carlos Alberto Della; Pellizzer, Eder Luis; Fontenelle, Isaddora

2017-01-01

This work evaluates the corrosion process caused by the presence of hydrogen sulfide in the biogas in natura, in steels commonly used in the construction of steam generator boilers, simulating conditions close to those found on the real application of these materials, exposing the test bodies directly to biogas in natura, flame of combustion and gases resulting from the combustion of this biofuel, in chimney. After 314 hours of exposure under the specified conditions, the corroded surfaces of...

Design and Testing of a Natural Convection Solar Tunnel Dryer for Mango

Directory of Open Access Journals (Sweden)

Isaac Nyambe Simate

2017-01-01

Full Text Available A natural convection solar tunnel dryer comprising three major units, a solar collector unit, a drying unit, and a vertical bare flat-plate chimney, was constructed. No-load tests with a horizontal configuration of air entry into the collector resulted in a bidirectional air flow in the dryer. To correct this undesirable situation, an air guide at the collector was incorporated to ensure that air entered in a vertical direction. To investigate its performance, drying experiments with mango were carried out at the University of Zambia, Department of Agricultural Engineering. Uncertainties in the parameters measured in the experiment were analysed and quantified. The results showed that, under solar radiation between 568.4 and 999.5 W/m2, air temperature of up to 65.8°C was attained at the collector unit. The average relative humidity values were 30.8%, 6.4%, and 8.4% for the ambient, collector, and drying unit, respectively. Under these conditions, mango with an initial moisture content of 85.5% (wet basis was dried to 13.0% (wet basis in 9.5 hours. The collector, drying, and pick-up efficiencies were found to be 24.7%, 12.8%, and 35.0%, respectively. The average temperature difference between the chimney air and ambient air was 12.1°C, and this was sufficient in driving the flow of air through the dryer.

Spatial Distribution of Viruses Associated with Planktonic and Attached Microbial Communities in Hydrothermal Environments

Science.gov (United States)

Nunoura, Takuro; Kazama, Hiromi; Noguchi, Takuroh; Inoue, Kazuhiro; Akashi, Hironori; Yamanaka, Toshiro; Toki, Tomohiro; Yamamoto, Masahiro; Furushima, Yasuo; Ueno, Yuichiro; Yamamoto, Hiroyuki; Takai, Ken

2012-01-01

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

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.

A TRMM/GPM retrieval of the total mean generator current for the global electric circuit

Science.gov (United States)

Peterson, Michael; Deierling, Wiebke; Liu, Chuntao; Mach, Douglas; Kalb, Christina

2017-09-01

A specialized satellite version of the passive microwave electric field retrieval algorithm (Peterson et al., 2015) is applied to observations from the Tropical Rainfall Measuring Mission (TRMM) and Global Precipitation Measurement (GPM) satellites to estimate the generator current for the Global Electric Circuit (GEC) and compute its temporal variability. By integrating retrieved Wilson currents from electrified clouds across the globe, we estimate a total mean current of between 1.4 kA (assuming the 7% fraction of electrified clouds producing downward currents measured by the ER-2 is representative) to 1.6 kA (assuming all electrified clouds contribute to the GEC). These current estimates come from all types of convective weather without preference, including Electrified Shower Clouds (ESCs). The diurnal distribution of the retrieved generator current is in excellent agreement with the Carnegie curve (RMS difference: 1.7%). The temporal variability of the total mean generator current ranges from 110% on semi-annual timescales (29% on an annual timescale) to 7.5% on decadal timescales with notable responses to the Madden-Julian Oscillation and El Nino Southern Oscillation. The geographical distribution of current includes significant contributions from oceanic regions in addition to the land-based tropical chimneys. The relative importance of the Americas and Asia chimneys compared to Africa is consistent with the best modern ground-based observations and further highlights the importance of ESCs for the GEC.

Steady-state solidification of aqueous ammonium chloride

Science.gov (United States)

Peppin, S. S. L.; Huppert, Herbert E.; Worster, M. Grae

We report on a series of experiments in which a Hele-Shaw cell containing aqueous solutions of NH4Cl was translated at prescribed rates through a steady temperature gradient. The salt formed the primary solid phase of a mushy layer as the solution solidified, with the salt-depleted residual fluid driving buoyancy-driven convection and the development of chimneys in the mushy layer. Depending on the operating conditions, several morphological transitions occurred. A regime diagram is presented quantifying these transitions as a function of freezing rate and the initial concentration of the solution. In general, for a given concentration, increasing the freezing rate caused the steady-state system to change from a convecting mushy layer with chimneys to a non-convecting mushy layer below a relatively quiescent liquid, and then to a much thinner mushy layer separated from the liquid by a region of active secondary nucleation. At higher initial concentrations the second of these states did not occur. At lower concentrations, but still above the eutectic, the mushy layer disappeared. A simple mathematical model of the system is developed which compares well with the experimental measurements of the intermediate, non-convecting state and serves as a benchmark against which to understand some of the effects of convection. Movies are available with the online version of the paper.

Effect of combined treatment with diuretics and gabapentin on convulsive threshold in mice.

Science.gov (United States)

Łukawski, Krzysztof; Swiderska, Grajyna; Czuczwar, Stanisław J

2013-01-01

Research data show that diuretics can have anticonvulsant properties. This study examined effects of ethacrynic acid, a loop diuretic, and hydrochlorothiazide, a thiazide-type diuretic, on the anticonvulsant activity of gabapentin, a newer antiepileptic drug, in the maximal electroshock seizure threshold test in mice. Diuretics were administered intraperitoneally (ip.) both acutely (single dose) and chronically (once daily for seven days). Electroconvulsions were produced by an alternating current (50 Hz, 500 V, 0.2 s stimulus duration) delivered via ear-clip electrodes by a generator. Additionally, the influence of combined treatment with the diuretics and gabapentin on motor performance in the chimney test has been assessed. In the current study, ethacrynic acid at the chronic dose of 12.5 mg/kg and the single dose of 100 mg/kg did not affect the anticonvulsant activity of gabapentin. Similarly, hydrochlorothiazide (100 mg/kg), both in acute and chronic experiments, had no effect on the gabapentin action. On the other hand, in the chimney test, the combined treatment with ethacrynic acid (100 mg/kg) and gabapentin (50 mg/kg) significantly impaired motor performance in mice. Based on the current preclinical findings, it can be suggested that the diuretics should not affect the anticonvulsant action of gabapentin in epileptic patients. However, the combination of ethacrynic acid with gabapentin may cause neurotoxicity.

Manufacturing and test of a low cost polypropylene bag to reduce the radioactive gas released by a radiopharmaceutical production facility

Energy Technology Data Exchange (ETDEWEB)

Tavares, Jose Carlos Freitas; Lacerda, Marco Aurelio de Sousa, E-mail: jcft@cdtn.b, E-mail: masl@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (SEPRA/ CDTN/CNEN-MG) Belo Horizonte, MG (Brazil). Servico de Protecao Radiologica; Nascimento, Leonardo Tafas Constantino do; Silva, Juliana Batista da, E-mail: ltcn@cdtn.b, E-mail: silvajb@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (SECPRA/ CDTN/CNEN-MG) Belo Horizonte, MG (Brazil). Secao de Producao de Radiofarmacos

2011-07-01

The main objective of this work was to evaluate the efficiency of a plastic gas storage bag to reduce the radioactive gas released by the chimney of a radiopharmaceutical production facility during the 2-[{sup 18}F]fluoro-2- deoxy-D-glucose ({sup 18}FDG) synthesis. The studied facility was the Development Centre of Nuclear Technology (CDTN/CNEN) in Belo Horizonte, Brazil. The bag was manufactured utilizing foils of polypropylene of 360 x 550 x 0.16 mm and disposable components of the cassette of the synthesizer. Two synthesis of {sup 18}FDG were done using the same hot cell and synthesizer to evaluate the efficiency of the bag. The manufactured bag was put in the gas exit of the synthesizer and the activity reported by the online radiation monitoring system in the first synthesis. These results were compared to the activity released in a synthesis performed without the bag. We observed when the bag was used the amount released was about 0.2% in 270 minutes. The second synthesis was performed without the bag, about 7,1% of the input activity was released by the exhaust of the facility in the same time interval. The bag presented a very good efficiency in the reducing of the radioactive gas released by the chimney of the radiopharmaceutical production facility. (author)

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.

Manufacturing and test of a low cost polypropylene bag to reduce the radioactive gas released by a radiopharmaceutical production facility

International Nuclear Information System (INIS)

Tavares, Jose Carlos Freitas; Lacerda, Marco Aurelio de Sousa; Nascimento, Leonardo Tafas Constantino do; Silva, Juliana Batista da

2011-01-01

The main objective of this work was to evaluate the efficiency of a plastic gas storage bag to reduce the radioactive gas released by the chimney of a radiopharmaceutical production facility during the 2-[ 18 F]fluoro-2- deoxy-D-glucose ( 18 FDG) synthesis. The studied facility was the Development Centre of Nuclear Technology (CDTN/CNEN) in Belo Horizonte, Brazil. The bag was manufactured utilizing foils of polypropylene of 360 x 550 x 0.16 mm and disposable components of the cassette of the synthesizer. Two synthesis of 18 FDG were done using the same hot cell and synthesizer to evaluate the efficiency of the bag. The manufactured bag was put in the gas exit of the synthesizer and the activity reported by the online radiation monitoring system in the first synthesis. These results were compared to the activity released in a synthesis performed without the bag. We observed when the bag was used the amount released was about 0.2% in 270 minutes. The second synthesis was performed without the bag, about 7,1% of the input activity was released by the exhaust of the facility in the same time interval. The bag presented a very good efficiency in the reducing of the radioactive gas released by the chimney of the radiopharmaceutical production facility. (author)

Proceedings of the 1985 conference on coal mine subsidence in the Rocky Mountain Region

Energy Technology Data Exchange (ETDEWEB)

Hynes, J.L. (ed.)

1986-01-01

A total of 20 papers were presented at the conference on the following subjects: reclamation projects; geological surveys; history and evolution of mining; essential components of mine subsidence; subsidence related damage; core recovery of poorly consolidated materials; evaluation of subsurface conditions; remote video inspection of abandoned coal mines; use of progressive failure model for subsidence prediction; chimney subsidence sinkhole development; analytical methods of subsidence prediction; monitoring networks; architectural mitigating measures; backfilling; awareness and planning; administrative aspects; mine subsidence insurance; risk management.

The future of the low temperature district heating reactor

International Nuclear Information System (INIS)

Lu Yingzhong; Wang Dazhong; Ma Changwen; Dong Duo; Tian Jiafu.

1984-01-01

In this paper, the role, development and situation of the low temperature district heating reactor (LTDHR) are briefly summarized. There are four types of LTDHR. They are PWR, reactor with boiling in the chimney, organic reactor and swimming pool reactor. The features of these reactors are introduced. The situation and role of the LTDHR in the future of the energy system are also discussed. The experiment on nuclear district heating with the swimming pool reactor in Qinghua Univ. is described briefly. (Author)

A WEB BASED SERVICE APPLICATION FOR VISUAL SINKHOLE INVENTORY INFORMATION SYSTEM; CASE STUDY OF KONYA CLOSED BASIN

OpenAIRE

ORHAN, Osman; YAKAR, Murat; KIRTILOĞLU, Osman Sami

2017-01-01

Sinkholes are commonly defined as deep pits giving the appearance of a chimney or well resulting by collapsing of underground rivers in horizontal or near-bedded lime stones or active cave ceilings. Sinkholes appear as deep pits in the so-called karst land, usually on limestones and carbonates that are easily rinsed with water. The sinkhole occurrences in our country are very often seen on the Obruk Plateau in the Konya Closed Basin. In Karapinar region and its surroundings located in this pl...

Passive quench arrest by a chimney induced deluge at every quench front

International Nuclear Information System (INIS)

Sydoriak, S.G.

1984-01-01

This chapter describes a magnet in which a growing quench stops itself spontaneously within a fraction of one winding turn because vapor in quench-heated channels generates a progressively increasing downflow of liquid in advance of each of the quench fronts. The downflow eventually becomes a deluge as the quench grows. The design of the multiple arrested quench magnet is discussed. It is shown how to construct a magnet so that if an arrested quench arises when it is at its highest operating current, peak nucleate boiling will exist in all quenching channels

The Archaeology of Smuggling and the Falmouth King's Pipe

Science.gov (United States)

Willis, Sam

2009-06-01

This article demonstrates the potential of an historical archaeology of smuggling and the value of an interdisciplinary approach to the study of smuggling and its prevention. By exploring the previously unstudied history of the King’s Pipe in Falmouth, a large chimney used for the destruction of tobacco, a rare survivor of many that once existed in England’s port cities, it demonstrates that archaeology could transform our understanding of smuggling and its prevention, and more broadly the history of crime and punishment in eighteenth century England.

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.

Energy. Annual meeting of the German Academy of Scientists Leopoldina 2003. Lectures

International Nuclear Information System (INIS)

Hausen, Harald zur

2004-01-01

Taking into account complexity, globality and sustainability of the energy sector the contributions of this volume provide a scientific point of view on energy generation and -utilization according to the latest findings. As well wind power and biomass are considered in detail as nuclear energy and nuclear fusion. The trends for energy utilization are critically analyzed. Further on technical questions (solar cells, fuel cells, solar chimneys, energy efficient facility management) and economical problems(e.g. deregulation in the power market) are comprehensively presented. (GL)

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

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

Gas cooled HTR

International Nuclear Information System (INIS)

Schweiger, F.

1985-01-01

In the He-cooled, graphite-moderated HTR with spherical fuel elements, the steam generator is fixed outside the pressure vessel. The heat exchangers are above the reactor level. The hot gases stream from the reactor bottom over the heat exchanger, through an annular space around the heat exchanger and through feed lines in the side reflector of the reactor back to its top part. This way, in case of shutdown there is a supplementary natural draught that helps the inner natural circulation (chimney draught effect). (orig./PW)

Zn isotope study of atmospheric emissions and dry depositions within a 5 km radius of a Pb-Zn refinery

Science.gov (United States)

Mattielli, Nadine; Petit, Jérôme C. J.; Deboudt, Karine; Flament, Pascal; Perdrix, Esperanza; Taillez, Aurélien; Rimetz-Planchon, Juliette; Weis, Dominique

The present paper examines the use of zinc isotopes as tracers of atmospheric sources and focuses on the potential fractionation of Zn isotopes through anthropogenic processes. In order to do so, Zn isotopic ratios are measured in enriched ores and airborne particles associated with pyrometallurgical activities of one of the major Pb-Zn refineries in France. Supporting the isotopic investigation, this paper also compares morphological and chemical characteristics of Zn particles collected on dry deposition plates ("environmental samples") placed within a 5 km radius of the smelter, with those of Zn particles collected inside the plant ("process samples"), i.e. dust collected from the main exhaust system of the plant. To ensure a constant isotopic "supply", the refinery processed a specific set of ores during the sampling campaigns, as agreed with the executive staff of the plant. Enriched ores and dust produced by the successive Zn extraction steps show strong isotope fractionation (from -0.66 to +0.22‰) mainly related to evaporation processes within the blast furnaces. Dust from the main chimney displays a δ 66Zn value of -0.67‰. Application of the Rayleigh equation to evaluate the fractionation factor associated with the Zn vapor produced after a free evaporation gives a range of αore/vapor from 1.0004 to 1.0008. The dry deposits, collected on plates downwind of the refinery, display δ 66Zn variations of up to +0.7‰. However, it is to be noted that between 190 and 1250 m from the main chimney of the refinery, the dry deposits show a high level of large (>10 μm) Zn, S, Fe and O bearing aggregates characterized by positive δ 66Zn values (+0.02 to +0.19‰). These airborne particles probably derive from the re-suspension of slag heaps and local emissions from the working-units. In contrast, from 1720 to 4560 m, the dry deposits are comprised of small (PM10) particles, including spherical Zn-bearing aggregates, showing negative δ 66Zn values (-0.52 to -0

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

Directory of Open Access Journals (Sweden)

Putri Nilakandi Perdanawati Pitoyo

2016-07-01

Full Text Available 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 sorting. Wastewater discharge of PROPER hotels ranged from 290.9 to 571.8 m3/day and non PROPER ranged from 8.4 to 98.1 m3/day with NH3 parameter values that exceed the quality standards. The quality of chimney emissions were still below the quality standard. The volume of the hazardous waste of PROPER hotels ranged from 66.1 to 181.9 kg/month and non PROPER ranged from 5.003 to 103.42 kg/month. Hazardous waste from the PROPER hotel which has been stored in the TPS hazardous waste. The volume of the solid waste of PROPER hotel ranged from 342.34 to 684.54 kg/day and non PROPER ranged from 4.83 to 181.51 kg/day. The PROPER and non PROPER hotel not sort the solid waste. The hotel performance in term of wastewater management, emission, hazardous, and solid waste is better at the PROPER hotel compared to non PROPER participants.

Hydrothermal vent fields discovered in the southern Gulf of California clarify role of habitat in augmenting regional diversity.

Science.gov (United States)

Goffredi, Shana K; Johnson, Shannon; Tunnicliffe, Verena; Caress, David; Clague, David; Escobar, Elva; Lundsten, Lonny; Paduan, Jennifer B; Rouse, Greg; Salcedo, Diana L; Soto, Luis A; Spelz-Madero, Ronald; Zierenberg, Robert; Vrijenhoek, Robert

2017-07-26

Hydrothermal vent communities are distributed along mid-ocean spreading ridges as isolated patches. While distance is a key factor influencing connectivity among sites, habitat characteristics are also critical. The Pescadero Basin (PB) and Alarcón Rise (AR) vent fields, recently discovered in the southern Gulf of California, are bounded by previously known vent localities (e.g. Guaymas Basin and 21° N East Pacific Rise); yet, the newly discovered vents differ markedly in substrata and vent fluid attributes. Out of 116 macrofaunal species observed or collected, only three species are shared among all four vent fields, while 73 occur at only one locality. Foundation species at basalt-hosted sulfide chimneys on the AR differ from the functional equivalents inhabiting sediment-hosted carbonate chimneys in the PB, only 75 km away. The dominant species of symbiont-hosting tubeworms and clams, and peripheral suspension-feeding taxa, differ between the sites. Notably, the PB vents host a limited and specialized fauna in which 17 of 26 species are unknown at other regional vents and many are new species. Rare sightings and captured larvae of the 'missing' species revealed that dispersal limitation is not responsible for differences in community composition at the neighbouring vent localities. Instead, larval recruitment-limiting habitat suitability probably favours species differentially. As scenarios develop to design conservation strategies around mining of seafloor sulfide deposits, these results illustrate that models encompassing habitat characteristics are needed to predict metacommunity structure. © 2017 The Authors.

The use of segregated heat sink structures to achieve enhanced passive cooling for outdoor wireless devices

International Nuclear Information System (INIS)

O'Flaherty, K; Punch, J

2014-01-01

Environmental standards which govern outdoor wireless equipment can stipulate stringent conditions: high solar loads (up to 1 kW/m 2 ), ambient temperatures as high as 55°C and negligible wind speeds (0 m/s). These challenges result in restrictions on power dissipation within a given envelope, due to the limited heat transfer rates achievable with passive cooling. This paper addresses an outdoor wireless device which features two segregated heat sink structures arranged vertically within a shielded chimney structure: a primary sink to cool temperature-sensitive components; and a secondary sink for high power devices. Enhanced convective cooling of the primary sink is achieved due to the increased mass flow within the chimney generated by the secondary sink. An unshielded heat sink was examined numerically, theoretically and experimentally, to verify the applicability of the methods employed. Nusselt numbers were compared for three cases: an unshielded heat sink; a sink located at the inlet of a shield; and a primary heat sink in a segregated structure. The heat sink, when placed at the inlet of a shield three times the length of the sink, augmented the Nusselt number by an average of 64% compared to the unshielded case. The Nusselt number of the primary was found to increase proportionally with the temperature of the secondary sink, and the optimum vertical spacing between the primary and secondary sinks was found to be close to zero, provided that conductive transfer between the sinks was suppressed.

Results of Laboratory Testing of 15 Cookstove Designs in Accordance with the ISO/IWA Tiers of Performance.

Science.gov (United States)

Still, Dean; Bentson, Samuel; Li, Haixi

2015-03-01

The widespread adoption and sustained use of modern cookstoves has the potential to reduce harmful effects to climate, health, and the well-being of approximately one-third of the world's population that currently rely on biomass fuel for cooking and heating. In an effort to understand and develop cleaner burning and more efficient cookstoves, 15 stove design and fuel/loading combinations were evaluated in the laboratory using the International Workshop Agreement's five-tiered (0-4) rating system for fuel use and emissions. The designs evaluated include rocket-type combustion chamber models including reduced firepower, sunken pots, and chimneys (three stoves); gasifier-type combustion chambers using prepared fuels in the form of wood pellets (four stoves); forced draft stoves with a small electric fan (five stoves); and a single insulated charcoal stove with preheated secondary air. It was found that a charcoal burning stove was the only stove to meet all the Tier 4 levels of performance. Achieving over 40% thermal efficiency at high power was made possible by reducing firepower and gaps around the pot, although batch-fed stoves generally do not "turn down" for optimal low power performance. While all stoves met Tier 4 for carbon monoxide, only stoves equipped with electrical fans reduced respirable particulate matter to Tier 4 levels. Finally, stoves with chimneys and integrated pots were fuel efficient and virtually eliminated indoor emissions. It is hoped that these design techniques will be useful in further development and evolution of high-performance cookstove designs.

Unusual “Knob-Like Chimney” Growth Forms on Acropora Species in the Caribbean

Directory of Open Access Journals (Sweden)

Andrea Rivera-Sosa

2018-02-01

Full Text Available This manuscript provides new insights on an unusual morphological plasticity growth form on Acropora spp. in the Caribbean. This abnormal knob-shaped growth is thought to be a progression from the damselfish “chimneys” that are commonly seen in coral-algal farms. However, the diameters of the observed knobs tend to be much larger on Acropora palmata, where they range from 1.37 to 5.44 cm in diameter, and they tend to be slightly smaller on A. prolifera, where they range from 1.1 to 2.72 cm in diameter. These knob-like chimney growths can affect entire colonies. The knobs are mostly covered with live tissue, while some knobs compete with turf algae. We hypothesize that these growths may be linked to stress from multiple predation and environmental conditions. Local stressors could synergistically influence the regeneration of scarred tissue and skeleton that result from predatory lesions, possibly leading to the formation of the knobs. Therefore, we provide preliminary data from a shallow reef site in coastal Honduras located within the Mesoamerican region where we found the knobs. To the best of our knowledge, the conditions that drive the occurrence of these unusual “knob-like chimneys” on Acropora spp. have not been previously assessed. Thus, we propose a series of guidelines to research the coral morphological plasticity that may be linked to this knob-like chimney phenomenon.

Gas hydrates in the Ulleung Basin, East Sea of Korea

Directory of Open Access Journals (Sweden)

Byong-Jae Ryu Michael Riedel

2017-01-01

Full Text Available To develop gas hydrates as a potential energy source, geophysical surveys and geological studies of gas hydrates in the Ulleung Basin, East Sea off the east coast of Korea have been carried out since 1997. Bottom-simulating reflector (BSR, initially used indicator for the potential presence of gas hydrates was first identified on seismic data acquired in 1998. Based on the early results of preliminary R&D project, 12367 km of 2D multichannel reflection seismic lines, 38 piston cores, and multi-beam echo-sounder data were collected from 2000 to 2004. The cores showed high amounts of total organic carbon and high residual hydrocarbon gas levels. Gas composition and isotope ratios define it as of primarily biogenic origin. In addition to the BSRs that are widespread across the basin, numerous chimney structures were found in seismic data. These features indicate a high potential of the Ulleung Basin to host significant amounts of gas hydrate. Dedicated geophysical surveys, geological and experimental studies were carried out culminating in two deep drilling expeditions, completed in 2007 and 2010. Sediment coring (including pressure coring, and a comprehensive well log program complements the regional studies and were used for a resource assessment. Two targets for a future test-production are currently proposed: pore-filling gas hydrate in sand-dominated sediments and massive occurrences of gas hydrate within chimney-like structures. An environmental impact study has been launched to evaluate any potential risks to production.

Radiological assessment report for the Lansdowne property, 105-107 East Stratford Avenue, Lansdowne, Pennsylvania, October-December 1984

International Nuclear Information System (INIS)

Wynveen, R.A.; Smith, W.H.; Sholeen, C.M.; Flynn, K.F.

1985-09-01

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

Radiological assessment report for the Lansdowne property, 105-107 East Stratford Avenue, Lansdowne, Pennsylvania, October-December 1984

Energy Technology Data Exchange (ETDEWEB)

Wynveen, R.A.; Smith, W.H.; Sholeen, C.M.; Flynn, K.F.

1985-09-01

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.

Measurement of Ar41 release from a TRIGA reactor

International Nuclear Information System (INIS)

Baers, B.; Kautto, A.M.T.

1978-01-01

The properties of four types of gamma sensitive (Ar-41 1.29 MeV) detectors were investigated: 10 GM tubes, 1 liquid scintillation detector, NaI(Tl)-detector and Ge(Li)-detector. The ratio of the integrated net counts per statistical uncertainty was used as a figure of merit. A uniform Ar-41 activity concentration of 14.8 Bq/m 3 was simulated with a Co-60 point source of 9.6 MBq and a measuring time of 10 min. Due to temperature instabilities the normal release was not clearly detected. Therefore the detector response was obtained for pulse releases. By weighting the experimental exposure estimate with the yearly wind distributions (velocity and direction), the yearly exposure arising from 1300 hours operation of the 250 kW TRIGA reactor was estimated to 40...100 μR/y (+100% -50%) at the test point (at the height of 13 meters) for an Ar-41 release of 440...1000 GBq/y (12...28 Ci/y). By applying a line source approximation the exposure at the ground level and close distances was estimated. The maximum average exposure at a distance of about 200 meters (10 times the height of the chimney) was estimated to be about 100 μR/y. (10 times the height of the chimney) was estimated to be about 100 yR/y. Thus the radiation dose to the public is much lower than generally applied limits

A novel design for construction of dwellings in radon prone areas of Ramsar

International Nuclear Information System (INIS)

Mortazavi, S.M.J.; Kazemi, E.; Nowrouzi, S.; Abdollahi, H.; Mortazavi, S.A.

2010-01-01

Radon can accumulate in residential places at sufficiently high levels. Indoor radon levels in some regions of Ramsar are up to 3700 Bq m -3 , a concentration that is much higher than US EPA recommended action level of 148 Bq m -3 (4 pCi/L). Radon is the 2 nd leading cause of lung cancer, after cigarette smoking. It is widely believed that there is no threshold for lung cancer from radon exposure. In this study after reviewing the meteorological changes of Ramsar over the past 50 years (1955-2005), a novel design for constructing dwellings in radon prone areas is introduced. Natural ventilation is a type of ventilation that is created by the differences in the distribution of air pressures around a building. The basic element of our design is enhancement of natural ventilation by making wind and chimney effect to move fresh air through dwellings. The buoyancy effect caused by temperature differences makes air flow. The size and location of openings in each dwelling determine the extent of natural ventilation. In our two-storey house model, wind speed and direction, relative humidity, average temperature, and especially the traditional architecture of the northern coastal part of Iran, are taken into account. Furthermore, in this model, windows and skylights, evergreen or deciduous trees and fireplace chimneys as well as construction materials and wall coverings are the key components of the natural ventilation system. (author)

Catalytic converters in the fireplace

International Nuclear Information System (INIS)

Kouki, J.

1995-01-01

In addition to selecting the appropriate means of heating and using dry fuel, the amount of harmful emissions contained by flue gases produced by fireplaces can be reduced by technical means. One such option is to use an oxidising catalytic converter. Tests at TTS Institute's Heating Studies Experimental Station have focused on two such converters (dense and coarse) mounted in light-weight iron heating stoves. The ability of the dense catalytic converter to oxidise carbon monoxide gases proved to be good. The concentration of carbon monoxide in the flue gases was reduced by as much as 90 %. Measurements conducted by VTT (Technical Research Centre of Finland) showed that the conversion of other gases, e.g. of methane, was good. The exhaust resistance caused by the dense converter was so great as to necessitate the mounting of a fluegas evacuation fan in the chimney for the purpose of creating sufficient draught. When relying on natural draught, the dense converter requires a chimney of at least 7 metres and a by-pass connection while the fire is being lit. In addition, the converter will have to be constructed to be less dense and this will mean that it's capability to oxidise non-combusted gases will be reduced. The coarse converter did not impair the draught but it's oxidising property was insufficient. With the tests over, the converter was not observed to have become blocked up by impurities

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

International Nuclear Information System (INIS)

Galicia, R.; La Rosa, J. de la; Stolik, S.

2012-01-01

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)

Power station stack gas emissions

International Nuclear Information System (INIS)

Hunwick, Richard J.

2006-01-01

There are increasing awareness and pressure to reduce emissions of acid rain and photochemical smog. There is a need to produce new control system and equipment to capture those emissions. The most visible form of pollutions are the chimney smoke, dust and particles of fly ash from mineral matter in the fuel. Acid gases are hard on structures and objects containing limestone. Coal fired power generation is likely to be able to sustain its competitive advantage as a clean source of electricity in comparison with nuclear power and natural gas

Design Of Fluidized-bed Incinerator

International Nuclear Information System (INIS)

Lee, Bong Hun

1992-04-01

This book tells of design of fluidized-bed incinerator, which includes outline of fluidized-bed incinerator such as definition, characteristic, structure of principle of incineration and summary of the system, facilities of incinerator with classification of incinerator apparatus of supply of air, combustion characteristic, burnup control and point of design of incinerator, preconditioning facilities on purpose, types and characteristic of that system, a crusher, point of design of preconditioning facilities, rapid progress equipment, ventilation equipment, chimney facilities, flue gas cooling facilities boiler equipment, and removal facility of HCI/SOX and NOX.

3D seismic expression of fluid migration and mud remobilization on the Gjallar Ridge, offshore mid-Norway

DEFF Research Database (Denmark)

Hansen, J.P.V.; Cartwright, J.A.; Huuse, M.

2005-01-01

This paper presents a three-dimensional (3D) seismic analysis of sediment remobilization and fluid migration in a 2000-km2 area above the Gjallar Ridge located in the Vøring Basin, offshore Norway. Three distinct types of mounded structures have been identified as resulting from focused fluid......-seated normal faults. Type B structures comprise relatively steep-sided mounds and are restricted to the pre-Miocene interval. They are often located above narrow zones of discontinuous low-amplitude reflections resembling gas chimneys. Some of the Type B structures are associated with stacked amplitude...

Restraint behavior of concrete under extreme thermal and hygral conditions

International Nuclear Information System (INIS)

Schwesinger, P.; Dommnich, F.

1989-01-01

Stresses due to temperature may be a considerable part of the whole loading of the structure especially in reactor vessels, chimneys and other structures. During using of this structures the heating cycle consisting of heating and cooling may be repeated for several times. On the other hand the initial load, the preloading time, the heating rate and the moisture of concrete can differ in respect of the design or utilization of the structure. The effect of this environmental factors on the restraint behavior of concrete is presented in this paper

Thermophilic bacteria associated with black smokers (= sulfide chimneys) along the East Pacific Rise.

OpenAIRE

Deming, J

1984-01-01

A des profondeurs de 2 600 m, le long de la dorsale Est-Pacifique, des cheminées de sulfures ou «fumeurs noirs» émettent des fluides à une température de 350°C dans des eaux froides. Plusieurs gaz dont CHU, H2, CO et N2O sont dissous dans ces fluides. Baross et ses collègues ont montré la production et l'utilisation de plusieurs de ces gaz par des communautés bactériennes, prélevées au niveau des fluides des «fumeurs noirs» à une latitude de 21°N, et cultivées à 100°Csous pression atmosphériq...

Analysis of the potential formation of a Breccia chimney beneath the WIPP repository

International Nuclear Information System (INIS)

Spiegler, P.

1982-05-01

This report evaluates the potential formation of a Breccia pipe beginning at the Bell Canyon aquifer beneath the WIPP repository and the resulting release of radioactivity to the surface. Rock mechanics considerations indicate that the formation of a Breccia pipe by collapse of a cavern is not reasonable. Even if rock mechanics is ignored, the overlying strata act as a barrier and would prevent the release of radioactivity to the biosphere. Gradual formation of a Breccia pipe is so slow that the plutonium-239 in the waste (one of the most important long-lived components) would decay during formation. If Bell Lake and San Simon Sinks are the surface manifestation of a regional deep dissolution wedge, such a wedge is too far removed to represent pipe forming activity near the WIPP site. The formation of a Breccia pipe under the WIPP repository is highly unlikely. If it did occur, the concentration of plutonium-239 in brine reaching the surface would be less than the maximum permissible concentration in water specified in the Code of Federal Regulation Title 10, part 20

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.

Use of the solar and eolic energy in the drying of bean seed at rural level

International Nuclear Information System (INIS)

Grajales Avila, W.; Racines Sanchez, L.E.

1985-01-01

The drying is a camera through which is made pass air heated in a solar collector, by means of a rotational fan impelled by the wind. The dryer is wooden and the zinc consists of five levels where the trays are deposited that contain the product. In the end of the chimney placed above the drying camera this the fan that is a rotor of corrugate fins; when rotating under the action of the wind it extracts air of the ventilation chimney; in the periods that the wind doesn't blow the drying it happens for natural convention. In the collector the badge absorbent is zinc colored corrugate of black; the mark is wooden, isolated in its inferior part with icopor and the cover a sheet of plastic. To evaluate the dryer they were carried out four drying rehearsals with seed of bean variety Calima. One observes that the bean drying with this dryer type is feasible even with cloudy or partially cloudy sky. The drying was satisfactory with the two loads of 200 and 400 kg. With the flow of air through the trays and for the load of 210 kg with flow around them; being the drying uniform for this it finishes. The quality of the seeds was not affected in the drying coke superior temperatures they were presented to 43-centigrade degrees. The dryer can adapt to individual necessities and conditions you specify of operation. It is recommended to carry out rehearsals for other agricultural products that allow knowing the capacity and functionality from the dryer to property level

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)

Radon as geological tracer

International Nuclear Information System (INIS)

Lacerda, T.; Anjos, R.M.; Silva, A.A.R. da; Yoshimura, E.M.

2012-01-01

Full text: This work presents measurements of 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 40 K, 232 Th and 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 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 -3 recommended by the International Commission of Radiological Protection (ICRP). The chimney effect shows the low mean concentration of radon in Los Condores. (author)

The Fogging Method with Variable of Nozle Diameter as the Mitigation Alternative for Spreading the Dust of Cement

Science.gov (United States)

Purwanta, J.; Marnoto, T.; Setyono, P.; Ramelan, A. H.

2018-03-01

The cement plant impacts on the lives of people around the factory site, one of them on the air quality, especially dust. Cement plant has made various efforts to mitigate dust generated, but the reality on the ground is still a lot of dust flying around either of the cement factory chimneys and transportation. The purpose of this study was to find the optimum condition of nozle diameter from the cement dust catcher, for mitigation the dust spread to around the cement plant. This study uses research methods such as collecting secondary data which includes data intensity rainfall, the average long rains, wind speed and direction as well as data quality monitoring dust around PT. Semen Gresik (Persero) Tbk. Tuban plant. To determine the wind direction propensity models, use a soft Windrose file. To determine the impact on the spread of dust into the environment using secondary data monitoring air quality. Results of the study is that the mitigation of dust around the cement plant is influenced by natural factors, namely the tendency of wind direction, rainfall and rainy days, and the rate of dust emission from the chimney. I try for operate the cement dust catcher with variable of nozle diameter. Finally, I find the optimum condition of nozle diameter for cement dust catcher is 1.40 mm, with line equation is y = 149.09.e 1.6237.x and error 5%. In that condition, nozle can make the fog with a good quality and it can catch the cement dust well.

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

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)

The sodium fire tests performed in the FAUNA facility on up to 12m2 fire areas

International Nuclear Information System (INIS)

Cherdron, W.; Jordan, S.

1983-08-01

The FAUNA test facility started operation in 1979. It serves to investigate large area sodium fires in closed containments and to study the generation, behaviour and removal of sodium fire aerosols. In this report, the experimental results of the 6 sodium pool fires are described which were performed with up to 500 kg of sodium in fire pans of 2 m 2 , 5 m 2 and 12 m 2 surface area, respectively. Both, the thermodynamic data and the data of the reaction kinetics of the fires were determined. In addition, the behaviour of the released aerosols during and after the fire was studied. On the basis of measurements of the temperature profiles at various levels above the fire areas it was shown that the convective flows above fire areas of different sizes in closed containments differ markedly and, obviously, exert an influence on the development of the fire and the release of particles. Whilst in rather small fires the gas above the pan rises as in a chimney and flows back on the walls, no chimney effect can be observed in a large pool fire. In rather large fires higher burning rates and aerosol release rates were observed. Some meters above the fire area temperatures around 300-400 0 C, temporarily even up to 700 0 C, were measured. The tests F5 and F6 were performed above all to observe the fire behaviour in terms of thermodynamics and reaction kinetics in a fully closed containment. (orig./RW) [de

Methane transport and emissions from soil as affected by water table and vascular plants.

Science.gov (United States)

Bhullar, Gurbir S; Iravani, Majid; Edwards, Peter J; Olde Venterink, Harry

2013-09-08

The important greenhouse gas (GHG) methane is produced naturally in anaerobic wetland soils. By affecting the production, oxidation and transport of methane to the atmosphere, plants have a major influence upon the quantities emitted by wetlands. Different species and functional plant groups have been shown to affect these processes differently, but our knowledge about how these effects are influenced by abiotic factors such as water regime and temperature remains limited. Here we present a mesocosm experiment comparing eight plant species for their effects on internal transport and overall emissions of methane under contrasting hydrological conditions. To quantify how much methane was transported internally through plants (the chimney effect), we blocked diffusion from the soil surface with an agar seal. We found that graminoids caused higher methane emissions than forbs, although the emissions from mesocosms with different species were either lower than or comparable to those from control mesocosms with no plant (i.e. bare soil). Species with a relatively greater root volume and a larger biomass exhibited a larger chimney effect, though overall methane emissions were negatively related to plant biomass. Emissions were also reduced by lowering the water table. We conclude that plant species (and functional groups) vary in the degree to which they transport methane to the atmosphere. However, a plant with a high capacity to transport methane does not necessarily emit more methane, as it may also cause more rhizosphere oxidation of methane. A shift in plant species composition from graminoids to forbs and/or from low to high productive species may lead to reduction of methane emissions.

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)

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.

Underground nuclear explosion effects in granite rock fracturing

International Nuclear Information System (INIS)

Derlich, S.

1970-01-01

On the Saharan nuclear test site in Hoggar granite, mechanical properties of the altered zones were studied by in situ and laboratory measurements. In situ methods of study are drillings, television, geophysical and permeability measurements. Fracturing is one of the most important nuclear explosion effects. Several altered zones were identified. There are: crushed zone, fractured zone and stressed zone. Collapse of crushed and fractured zone formed the chimney. The extent of each zone can be expressed in terms of yield and of characteristic parameters. Such results are of main interest for industrial uses of underground nuclear explosives in hard rock. (author)

Solar thermal utilization--an overview

International Nuclear Information System (INIS)

Chen Deming; Xu Gang

2007-01-01

Solar energy is an ideal renewable energy source and its thermal utilization is one of its most important applications. We review the status of solar thermal utilization, including: (1) developed technologies which are already widely used all over the world, such as solar assisted water heaters, solar cookers, solar heated buildings and so on; (2) advanced technologies which are still in the development or laboratory stage and could have more innovative applications, including thermal power generation, refrigeration, hydrogen production, desalination, and chimneys; (3) major problems which need to be resolved for advanced utilizaiton of solar thermal energy. (authors)

Simulation of the Gamma Dose Rate in Loss of Pool Water Accident of the Second Egyptian Research Reactor ETRR-2

International Nuclear Information System (INIS)

Amin, E.; Saleh, H.; Ashoub, N.

2000-01-01

The Second Egyptian Research Reactor ETRR-2, is a pool type reactor, a sudden loss of pool water resulting of leaving the core region un-covered. The reactor core is surrounded by chimney chambers whose water is isolated from pool water. This accident would lead to significant external dose. A model is developed and is used to calculate the dose rates for key access and traffic plans from indirect line of sight of the core have a maximum dose rate. The model developed uses the discrete ordinate method as implemented in the code DOT 3.5

Simulation of the gamma dose rate in a loss of pool water accident of the second Egyptian research reactor ET-RR-2

International Nuclear Information System (INIS)

Amin, E.; Saleh, H.G.; Ashoub, N.

2002-01-01

The second Egyptian research reactor ET-RR-2, is a pool type reactor. A sudden loss of pool water would leave the core region uncovered. The reactor core is surrounded by chimney chambers with water isolated from the pool water. This accident would lead to significant external doses. A model is developed and used to calculate the dose rates for key access-areas and traffic plans from indirect line of sight of the core which have a maximum dose rate. The model developed uses the discrete ordinate method as implemented in the code DOT3.5. (orig.) [de

Simulation of a pool type research reactor

International Nuclear Information System (INIS)

Oliveira, Andre Felipe da Silva de; Moreira, Maria de Lourdes

2011-01-01

Computational fluid dynamic is used to simulate natural circulation condition after a research reactor shutdown. A benchmark problem was used to test the viability of usage such code to simulate the reactor model. A model which contains the core, the pool, the reflector tank, the circulation pipes and chimney was simulated. The reactor core contained in the full scale model was represented by a porous media. The parameters of porous media were obtained from a separate CFD analysis of the full core model. Results demonstrate that such studies can be carried out for research and test of reactors design. (author)

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...... 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...

Nuclear power and its role in improving worldwide environment

International Nuclear Information System (INIS)

Elsaiedi, A.F.

1992-01-01

The first Un conference on the environment was held in stockholm in 1972. Concerns were voiced out warning against problems of acid rain leading to dying forests; decaying cities due to high emissions of So 2 and No x; increased smog linked to emissions from stacks and chimneys; and most serious of all the global threat of greenhouse effect which is linked mainly to emissions of Co 2 ; So 2 , No x and Co 2 emissions come mainly from burning of fossil fuel. An additional source of Co 2 comes from deforestation, however it only composes nearly 20% of the present global emissions

Underground nuclear explosion effects in granite rock fracturing

Energy Technology Data Exchange (ETDEWEB)

Derlich, S [Commissariat a l' Energie Atomique, Centre d' Etude de Bruyeres-le-Chatel (France)

1970-05-01

On the Saharan nuclear test site in Hoggar granite, mechanical properties of the altered zones were studied by in situ and laboratory measurements. In situ methods of study are drillings, television, geophysical and permeability measurements. Fracturing is one of the most important nuclear explosion effects. Several altered zones were identified. There are: crushed zone, fractured zone and stressed zone. Collapse of crushed and fractured zone formed the chimney. The extent of each zone can be expressed in terms of yield and of characteristic parameters. Such results are of main interest for industrial uses of underground nuclear explosives in hard rock. (author)

The structural design of the experimental equipment for unconventional heating water using heat transfer surfaces located in the heat source

Directory of Open Access Journals (Sweden)

Jandačka J.

2013-04-01

Full Text Available Flue gas temperature at throat of most industrially produced fireplaces is around 250 to 350 °C. It's quite interesting thermal potential, which can be even before sucking up the chimney back utilize. One of the potential uses of this device to heat the hot water. Article refers to the structural design of such a device, which works with the transfer of heat through a substance changes phase from liquid to steam in a sealed tube (heat pipe. Benefits of heat pipes is their light weight, the thermal effect of a rapid and low maintenance costs.

The structural design of the experimental equipment for unconventional heating water using heat transfer surfaces located in the heat source

Science.gov (United States)

Kaduchová, K.; Lenhard, R.; Gavlas, S.; Jandačka, J.

2013-04-01

Flue gas temperature at throat of most industrially produced fireplaces is around 250 to 350 °C. It's quite interesting thermal potential, which can be even before sucking up the chimney back utilize. One of the potential uses of this device to heat the hot water. Article refers to the structural design of such a device, which works with the transfer of heat through a substance changes phase from liquid to steam in a sealed tube (heat pipe). Benefits of heat pipes is their light weight, the thermal effect of a rapid and low maintenance costs.

Economic policy and renewable energy

International Nuclear Information System (INIS)

Klaiss, H.

1993-01-01

The paper summarizes the economical conclusions of the 6th Symposium on Solar Thermal Concentrating Technologies which take place at Mojacar (Almeria). Parabolic throughs, Central Receiver Systems, dish stirling and Solar chimneys will commercial utilization by the year 2000. Levalized Energy Cost (Solar) is still higher than conventional (coal). Only the utilization of environmental parameters like ''CO2 avoided'' may contribute to market penetration. Concerning siting, it becomes clear that only those countries below 40 degree latitude, (Madrid, Nepal, Ankara) are acceptable. A desregulation of the electrical market is necessary for solar penetration, mainly in developing countries

Injury to Akamatsu (Pinus densiflora Sieb. et Zucc. ) forest in the vicinity of the smelting works at Hitachi

Energy Technology Data Exchange (ETDEWEB)

Okanoue, M

1958-03-01

In the summer of 1965, smoke from a smelter at Hitachi caused injury to a national forest approximately one to three km distant. The smelter had been equipped with control devices and no previous injuries had been reported. An investigation of meteorological conditions at the time of the emission revealed the presence of a temperature inversion between Mt. Kamimine (594 m) and Sukegawa (52 m). However, these inversions are not uncommon in the area. Presumably, poisonous gas was emitted from the smelter chimney as a result of equipment malfunction just at the time of unfavorable meteorological conditions.

Redemptive Family Narratives: Olga Lengyel and the Textuality of the Holocaust*

Science.gov (United States)

Turda, Marius

2016-01-01

Memoirs written by Holocaust survivors and (in some cases) their testimonies retain a salience unmatched by other historical sources. This article discusses one such memoir, Olga Lengyel’s Five Chimneys, alongside her 1998 testimony, aiming to engage with broader methodological issues relating to the history of the Holocaust, particularly those about memory, narrative and textuality. Through a detailed discussion of certain moments shaping Olga Lengyel’s personal experience, both pre-and post-arrival in Auschwitz, the article captures the tensions and contradictions characterizing the harrowing story of one woman’s loss of family in the Holocaust. PMID:27959969

Nuclear reactor lid cooling which can work by natural circulation

International Nuclear Information System (INIS)

Wagner, J.

1985-01-01

The well-known air cooling of the lid of liquid metal cooled nuclear reactors is improved by the start of natural convection flow ensuring removal of heat in a sufficiently short time, if the blower fails. Go and return branches of the individual cooling circuits are arranged at different heights for this purpose. The circulation is supported by opening valves, which provide a direct path into the reactor building for the cooling air. The draught can be increased by setting up special chimneys. The start of circulation is aided by the temporary opening of another valve. (orig.) [de

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)

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

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

Science.gov (United States)

2013-12-02

... Service (FIRS) at 1-800-877-8339 between 8 a.m. and 8 p.m., Eastern Time, Monday through Friday..., as well as objects of deep cultural and educational value. The plan will also provide for continued... Supervisor. Scoping Process This notice of intent initiates the scoping process, which guides the development...

Formation of carbonate chimneys in the Mediterranean Sea linked to deep-water oxygen depletion

NARCIS (Netherlands)

Bayon, G.; Dupré, S.; Ponzevera, E.; Etoubleau, J.; Chéron, S.; Pierre, C.; Mascle, J.; Boetius, A.; de Lange, G.J.

2013-01-01

Marine sediments at ocean margins vent substantial amounts of methane1, 2. Microbial oxidation of the methane released can trigger the precipitation of carbonate within sediments and support a broad diversity of seafloor ecosystems3, 4. The factors controlling microbial activity and carbonate

Childhood asthma and indoor woodsmoke from cooking in Guatemala.

Science.gov (United States)

Schei, Morten A; Hessen, Jens O; Smith, Kirk R; Bruce, Nigel; McCracken, John; Lopez, Victorina

2004-01-01

We estimated the prevalence and severity of asthma, and the association with cooking on open wood fires, as preparation for a large-scale randomized field trial on effects of indoor air pollution and child health. This is one of the first systematic studies of asthma and indoor wood-smoke pollution and to our knowledge the first asthma study in a purely indigeneous population in Latin America. The mothers of 1058 children aged 4-6 years were interviewed, using the standardized ISAAC (International Study of Asthma and Allergies in Childhood) procedures and questionnaire. The study population is a Mam-speaking (Maya), indigenous group living at relatively high altitude (2000 m) in Western Guatemalan Highlands. We found that asthma prevalence is low among indigenous children in Guatemala, compared to other populations in Latin America. Only 3.3% of the children reported wheezing symptoms in the last 12 months, and 72% wheezing symptoms ever. The majority of the current wheezers had at least one of the criteria for severe asthma. The prevalence of all the symptoms of asthma was higher in children from households that used open fires compared to improved stoves with chimneys. In a logistic regression model, use of open fire for cooking was a significant risk factor for a number of asthma symptoms, with odds ratios varying from 2.0 to 3.5. Among the different cooking technologies (1-improved stove with chimney, 2-mixture of gas and open fire, 3-open fire) trends of higher prevalence with more pollution was found for some of the symptoms. Hence use of open fire for cooking, may be an important risk factor for asthma symptoms and severity.

The Windscale piles initial decommissioning programme

International Nuclear Information System (INIS)

Boorman, T.; Woodacre, A.

1992-01-01

The two Windscale Piles, the first large scale nuclear reactors built in the UK were constructed in the late 1940's and operated until the accident in Pile No 1 caused their permanent shutdown in 1957. Following a period of care and maintenance, a programme of initial decommissioning has begun aimed at establishing a satisfactory long-term safe condition for the Windscale Piles Complex with minimum maintenance commitments. For the chimneys this involves the removal of the top filter sections. The pond will be emptied and cleaned. For the Piles the initial phase includes the consideration of options for long-term decommissioning solutions. (author)

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)

Decommissioning in British Nuclear Fuels plc

International Nuclear Information System (INIS)

Colquhoun, A.

1988-01-01

Decommissioning projects at the BNFL Sellafield site have been selected taking the following into account; the need to gain experience in preparation for the decommissioning of the Magnox reactors and for the post Magnox stage; the need to develop larger scale projects; the need to be cost effective and to foster long term safety. The balance between prompt or delayed decommissioning has to consider operator dose uptake and radioactive waste management. The ten year plan for decommissioning at Sellafield is described briefly. Currently decommissioning is of the fuel pond and decanning plant, the Windscale Pile Chimneys, the coprecipitation plant and the uranium recovery plant. (author)

Genetic Optimization and Simulation of a Piezoelectric Pipe-Crawling Inspection Robot

Science.gov (United States)

Hollinger, Geoffrey A.; Briscoe, Jeri M.

2004-01-01

Using the DarwinZk development software, a genetic algorithm (GA) was used to design and optimize a pipe-crawling robot for parameters such as mass, power consumption, and joint extension to further the research of the Miniature Inspection Systems Technology (MIST) team. In an attempt to improve on existing designs, a new robot was developed, the piezo robot. The final proposed design uses piezoelectric expansion actuators to move the robot with a 'chimneying' method employed by mountain climbers and greatly improves on previous designs in load bearing ability, pipe traversing specifications, and field usability. This research shows the advantages of GA assisted design in the field of robotics.

The Windscale piles - past, present and future

International Nuclear Information System (INIS)

Jones, J.M.; Adams, A.L.

1987-01-01

The paper concerns the Windscale reactor piles, in which a fire occurred in the core of pile 1 thirty years ago. A description is given of the two Windscale piles, along with the events leading up to the accident, and the state of the piles following shutdown. The surveillance and maintenance to ensure that the pile and associated buildings were in a safe condition is outlined. The present state of the core, water ducts and pile chimneys is described. The present and future programme of work to ensure long term safety is discussed. This includes the initial steps in decommissioning of the piles. (U.K.)

Application of genetic algorithm for optimization the safety system of the nuclear reactor

International Nuclear Information System (INIS)

El-Sayed Wahed, M.; Ibrahim, W.Z.; Effat, A.M.

2009-01-01

The purpose of this paper is to present an approach to optimization in which every target is considered as a separate objective to be optimized. Multi-objective optimization is a powerful tool for resolving conflicting objectives in engineering design and numerous other fields. One approach to solve multi-objective optimization problems is the non-dominated sorting genetic algorithm (NSGA). Genetic algorithm (GA) was applied in regarding the choice of the time intervals for the periodic testing of the components of the chimney water injection system (CWIS) of the 22 MW open pool multipurpose reactor (MPR), ETRR-2, at the Egyptian Atomic Energy Authority, has been used as a case study. (authors)

Distillation, destructive

Energy Technology Data Exchange (ETDEWEB)

Bell, T

1863-09-14

Shales and other bituminous minerals are distilled in horizontal retorts arranged side by side and with furnaces beneath their front ends. The furnace gases pass, preferably through a brickwork grating, into spaces between the retorts and beneath a horizontal partition towards the back ends. They return above the partition to the front of the retorts, and finally enter a horizontal flue leading to a chimney. The front end of each retort is fitted with a hopper for charging and with a door for discharging. The products of distillation pass through perforated partitions inside the retorts and are conveyed away by pipes at the back.

Preliminary analysis of the KAERI RCCS Experiment Using GAMMA+

Energy Technology Data Exchange (ETDEWEB)

Khoza, Samukelisiwe; Tak, Nam-il; Lim, Hong-Sik; Lee, Sung-Nam; Cho, Bong-Hyun; Kim, Jong-Hwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-05-15

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+.

Some effects of smelter pollution northeast of Falconbridge, Ontario

Energy Technology Data Exchange (ETDEWEB)

Gorham, E

1960-01-01

A study along a line northwest from the metal smelter at Falconbridge, Ontario, reveals that strong sulphate accumulation in the surface soil occurs only within about one mile of the chimneys emitting sulphur dioxide pollution while effects upon the soil drainage waters are marked to a distance of nearly two miles, and still clearly evident 10 or more miles away. The number of species present in the flora declines sharply within about four miles of the smelter, but certain species (e.g. Pinus strobus, Vaccinium myrtilloides) disappear at much greater distances. Among the most tolerant species are Acer rubrum, Quercus rubra, Sambucus pubens, and Polygonum cilinode.

Methodology of adjustment point in the post treatment of gaseous effluents

International Nuclear Information System (INIS)

Vizuet G, J.; Molina, G.

2005-01-01

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)

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

Photoionization of the diffuse interstellar medium and galactic halo by OB associtations

Science.gov (United States)

Dove, James B.; Shull, J. Michael

1994-01-01

Assuming smoothly varying H I distributions in te Galactic disk, we have calculated the geometry of diffuse II regions due to OB associations in the Galactic plane. Near the solar circle, OB associations with a Lyman continuum (Lyc) photon luminosity Psi(sub Lyc) = 3.3 x 10(exp 7) cm(exp -2) s(exp -1), produce H II regions that are density bounded in the vertical direction (H II chimneys) allowing Lyc to escape the gaseous disk and penetrate into the Galactic halo. We provide analytic formulae for the Lyc escape fraction as functions of S(sub 0) O-star catalog of Garmany and a new Lyc stellar stellar Lyc stellar flux calibration, we find a production rate of Lyc photons by OB associations within 2.5 kpc of Psi(sub Lyc) = 3.3 x 10(exp 7) cm(exp -2) s(exp -1). Integrating the fraction of Lyc photons that escape the disk over our adopted luminosity function of OB associations, we estimate that approximately 7% of the ionizing photons, or Phi(sub Lyc) = 2.3 x 10(exp 6) cm(exp -2) s(exp -1), escape each side of the H I disk layer and penetrate the diffuse ionized medium ('Reynolds layer'). This flux is sufficient to explain the potoionization of this, although we have not constructed a model for the observed H-alpha emission and pulsar dispersion measures that is fully consistent with the absorption rate of Lyc in the H II layer. Since our quiescent model does not account for the effects of dynamic chimneys and superbubbles, which should enhance Lyc escape, we conclude the O stars are the probable source of ionizing radiation for the Reynolds layer. For a random distribution of OB associations throughout the disk, the Lyc flux is nearly uniform for heights Z is greater than approximately 0.8 kpc above the midplane.

Submarine Hydrothermal Activity and Gold-Rich Mineralization at Brothers Volcano, Southern Kermadec Arc, New Zealand

Science.gov (United States)

de Ronde, C. E.; Massoth, G. J.; Christenson, B. W.; Butterfield, D. A.; Ishibashi, J.; Hannington, M. D.; Ditchburn, B. G.; Embley, R. W.; Lupton, J. E.; Kamenetsky, D.; Reyes, A. G.; Lahr, J.; Takai, K.

2006-12-01

Brothers volcano is one of several hydrothermally active volcanoes that occur along the Kermadec active arc front, NE of New Zealand. It forms an elongate edifice 13 km long by 8 km across that strikes NW-SE. The volcano has a caldera with a basal diameter of ~3 km and a floor at 1,850 m below sea level, surrounded by 290 to 530 m high walls. A volcanic cone of dacite rises 350 m from the caldera floor and partially coalesces with the southern caldera wall. Three hydrothermal sites have been located; on the NW caldera wall, on the SE caldera wall, and on the dacite cone. The NW caldera vent site is a long-term hydrothermal system that is today dominated by evolved seawater but has had episodic injections of magmatic fluid. The SE caldera site represents the main upflow of a relatively well-established magmatic-hydrothermal system on the seafloor where sulfide-rich chimneys are extant. The cone site is a nascent magmatic-hydrothermal system where crack zones localize upwelling acidic waters. Each of these different vent sites represent diverse parts of an evolving hydrothermal system, any one of which may be typical of submarine volcanic arcs. Hydrothermal venting is today occurring at the NW caldera and cone sites. The former is characterized by high-temperature (up to 302°C) venting with pH down to 2.8, low Mg and SO4 values, Cl between 510 and 760 mM, elevated Si and increasing Fe and Mn values with increasing Cl concentrations, consistent with a mostly Cl-enriched endmember. By contrast, vent fluids from the cone site are gas-rich (up to 220 mM total gas), have temperatures 30 ppm) zones in some chimneys formed over a short period of time, coincident with pulses of magmatic fluid into the hydrothermal system.

How to transform an asphalt concrete pavement into a solar turbine

International Nuclear Information System (INIS)

García, Alvaro; Partl, Manfred N.

2014-01-01

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

Field measurements of tracer gas transport by barometric pumping

International Nuclear Information System (INIS)

Lagus, P.L.; McKinnis, W.B.; Hearst, J.R.; Burkhard, N.R.; Smith, C.F.

1994-01-01

Vertical gas motions induced by barometric pressure variations can carry radioactive gases out of the rubblized region produced by an underground nuclear explosion, through overburden rock, into the atmosphere. To better quantify transit time and amount of transport, field experiments were conducted at two sites on Pahute Mesa, Kapelli and Tierra, where radioactive gases had been earlier detected in surface cracks. At each site, two tracer gases were injected into the rubblized chimney 300-400 m beneath the surface and their arrival was monitored by concentration measurements in gas samples extracted from shallow collection holes. The first ''active'' tracer was driven by a large quantity of injected air; the second ''passive'' tracer was introduced with minimal gas drive to observe the natural transport by barometric pumping. Kapelli was injected in the fall of 1990, followed by Tierra in the fall of 1991. Data was collected at both sites through the summer of 1993. At both sites, no surface arrival of tracer was observed during the active phase of the experiment despite the injection of several million cubic feet of air, suggesting that cavity pressurization is likely to induce horizontal transport along high permeability layers rather than vertical transport to the surface. In contrast, the vertical pressure gradients associated with barometric pumping brought both tracers to the surface in comparable concentrations within three months at Kapelli, whereas 15 months elapsed before surface arrival at Tierra. At Kapelli, a quasisteady pumping regime was established, with tracer concentrations in effluent gases 1000 times smaller than concentrations thought to exist in the chimney. Tracer concentrations observed at Tierra were typically an order of magnitude smaller. Comparisons with theoretical calculations suggest that the gases are traveling through ∼1 millimeter vertical fractures spaced 2 to 4 meters apart. 6 refs., 18 figs., 3 tabs

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.

Native gold and gold-rich sulfide deposits in a submarine basaltic caldera, Higashi-Aogashima hydrothermal field, Izu-Ogasawara frontal arc, Japan

Science.gov (United States)

Iizasa, Kokichi; Asada, Akira; Mizuno, Katsunori; Katase, Fuyuki; Lee, Sangkyun; Kojima, Mitsuhiro; Ogawa, Nobuhiro

2018-04-01

Sulfide deposits with extremely high Au concentrations (up to 275 ppm; avg. 102 ppm, n = 15), high Au/Ag ratios (0.24, n = 15), and low Cu/(Cu + Zn) ratios (0.03, n = 15) were discovered in 2015 in active hydrothermal fields at a water depth of 760 m in a basalt-dominated submarine caldera in the Izu-Ogasawara frontal arc, Japan. Native gold grains occur in massive sulfide fragments, concretions, and metalliferous sediments from a sulfide mound (40 m across and 20 m high) with up to 30-m-high black smoker chimneys. Tiny native gold grains up to 14 μm in diameter are mainly present in sulfide fallouts from chimney orifices and plumes. Larger native gold grains up to 150 μm long occur mostly as discrete particles and/or with amorphous silica and sulfides. The larger gold grains are interpreted to represent direct precipitation from Au-bearing hydrothermal fluids circulating in and/or beneath the unconsolidated sulfide mound deposits. Sulfur isotope compositions from a limited number of sulfide separates (n = 4) range from 4.3 to 5.8‰ δ34S, similar to the quaternary volcanic rocks of the arc. Barite separates have values of 22.2 and 23.1‰, close to modern seawater values, and indicate probable seawater sulfate origin. The Cu, Zn, and Pb concentrations in bulk samples of sulfide-rich rocks are similar to those of volcanogenic massive sulfides formed in continental crustal environments. The gold is interpreted to have formed by low-temperature hydrothermal activity, perhaps genetically different from systems with documented magmatic contributions or from seafloor hydrothermal systems in other island arc settings. Its presence suggests that basalt-dominated submarine calderas situated on relatively thick continental crust in an intraoceanic arc setting such as the Higashi-Aogashima knoll caldera may be perspective for gold mineralization.

Layered hydrothermal barite-sulfide mound field, East Diamante Caldera, Mariana volcanic arc

Science.gov (United States)

Hein, James R.; de Ronde, Cornel E. J.; Koski, Randolph A.; Ditchburn, Robert G.; Mizell, Kira; Tamura, Yoshihiko; Stern, Robert J.; Conrad, Tracey; Ishizuka, Osamu; Leybourne, Matthew I.

2014-01-01

East Diamante is a submarine volcano in the southern Mariana arc that is host to a complex caldera ~5 × 10 km (elongated ENE-WSW) that is breached along its northern and southwestern sectors. A large field of barite-sulfide mounds was discovered in June 2009 and revisited in July 2010 with the R/V Natsushima, using the ROV Hyper-Dolphin. The mound field occurs on the northeast flank of a cluster of resurgent dacite domes in the central caldera, near an active black smoker vent field. A 40Ar/39Ar age of 20,000 ± 4000 years was obtained from a dacite sample. The mound field is aligned along a series of fractures and extends for more than 180 m east-west and >120 m north-south. Individual mounds are typically 1 to 3 m tall and 0.5 to 2 m wide, with lengths from about 3 to 8 m. The mounds are dominated by barite + sphalerite layers with the margins of each layer composed of barite with disseminated sulfides. Rare, inactive spires and chimneys sit atop some mounds and also occur as clusters away from the mounds. Iron and Mn oxides are currently forming small (caldera, mineralization resulted from focused flow along small segments of linear fractures rather than from a point source, typical of hydrothermal chimney fields. Based on the mineral assemblage, the maximum fluid temperatures were ~260°C, near the boiling point for the water depths of the mound field (367–406 m). Lateral fluid flow within the mounds precipitated interstitial sphalerite, silica, and Pb minerals within a network of barite with disseminated sulfides; silica was the final phase to precipitate. The current low-temperature precipitation of Fe and Mn oxides and silica may represent rejuvenation of the system.

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.

The CHESHIRE Migration Experiment A Summary Report

Energy Technology Data Exchange (ETDEWEB)

David A. Sawyer; Joseph L. Thompson; David K. Smith

1999-10-01

The CHESHIRE nuclear weapon test was detonated in 1976 in fractured volcanic rock at the Nevada Test Site (NTS). This testis representative of many other high-yield tests conducted below the water table in the Pahute Mesa area of the NTS. Since 1976 we have been studying the movement of test-related radionuclides within a few hundred meters of the explosion cavity. CHESHIRE is the only nuclear test characterized before, immediately after, and for decades following the detonation and provides data on both the prompt and long-term dispersal of radionuclides after an underground nuclear test. For this reason it is a unique field-scale transport experiment. Solid and fluid samples were collected from a drill back hole extending into and through the cavity in order to measure the initial distributions of radionuclides after the detonation. We subsequently pumped and sampled water from the cavity region and from a hydraulically transmissive zone about 400 m higher in the collapse chimney. A satellite well was also drilled 380 m down gradient from CHESHIRE and intercepted radionuclides (including tritium in high concentration) being transported through transmissive aquifers. Studies of radionuclide migration at CHESHIRE documented for the first time at the NTS the transport of relatively insoluble radionuclides (e.g., europium isotopes) with colloids moving in the groundwater. Water was pumped again from the cavity and chimney horizons in 1998 in order to observe the evolution of the hydrologic source term after several decades. Recent comprehensive studies of the geology and hydrology at the CHESHIRE site have improved predictions of radionuclide migration in the context of a regional groundwater flow model. This report provides unclassified data and describes a conceptual model for radionuclide migration associated with a nuclear test that is applicable to other tests on Pahute Mesa similar in yield, hydrogeologic setting, and age.

Remaining Sites Verification Package for the 100-B-18, 184-B Powerhouse Debris Pile. Attachment to Waste Site Reclassification Form 2007-020

International Nuclear Information System (INIS)

Dittmer, L.M.

2007-01-01

The 100-B-18 Powerhouse Debris Pile contained miscellaneous demolition waste from the decommissioning activities of the 184-B Powerhouse. The debris covered an area roughly 15 m by 30 m and included materials such as concrete blocks, mixed aggregate/concrete slabs, stone rubble, asphalt rubble, traces of tar/coal, broken fluorescent lights, brick chimney remnants, and rubber hoses. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River

Theoretical assessment of evaporation rate of isolated water drop under the conditions of cooling tower of thermal power plant

Directory of Open Access Journals (Sweden)

Shevelev Sergey

2017-01-01

Full Text Available The purpose of the work is numerical modelling of heat and mass transfer at evaporation of water drops under the conditions which are typical for a modern chimney-type cooling tower of a thermal power plant. The dual task of heat and mass transfer with movable boundary at convective cooling and evaporation for a ‘drop–humid air’ system in a spherical coordinate system has been solved. It has been shown that there is a rapid decline of water evaporation rate at the initial stage of the process according to temperature decrease of its surface. It has been stated that the effect of evaporation rate decrease appears greatly in the area of small radiuses.

Seismic isolation in New Zealand

International Nuclear Information System (INIS)

Skinner, R.I.; Robinson, W.H.; McVerry, G.H.

1989-01-01

Bridges, buildings, and industrial equipment can be given increased protection from earthquake damage by limiting the earthquake attack through seismic isolation. A broad summary of the seismic responses of base-isolated structures is of considerable assistance for their preliminary design. Seismic isolation as already used in New Zealand consists of a flexible base or support combined with some form of energy-dissipating device, usually involving the hysteretic working of steel or lead. This paper presents examples of the New Zealand experience, where seismic isolation has been used for 42 bridges, 3 buildings, a tall chimney, and high-voltage capacitor banks. Additional seismic response factors, which may be important for nuclear power plants, are also discussed briefly

Field survey and damage assessment of the Mineral, Virginia, earthquake of August 23, 2011

Science.gov (United States)

Thomas, Helen R.; Turkle, Katharine

2013-01-01

The town of Mineral, Virginia (Va.), underwent an M=5.8 earthquake on August 23, 2011. A U.S. Geological Survey team was sent to visually inspect and document the damage in the cities of Richmond, Charlottesville, Louisa, and Mineral, Va. Our inspection concluded that the Modified Mercalli Intensity rating of moderate (V) to very strong (VII) is consistent with the expected and observed damage at these locations. Louisa County, Va., sustained the most extensive damage. We photographed fallen chimneys, collapsed walls, and cracked foundations. From visual inspection of the above-listed locations, this report catalogs the range and extent of damage from the August 23, 2011, earthquake for future reference and analysis.

Nuclear Energy and the Environment. Addendum to the Agency's Report to the Economic and Social Council of the United Nations for 1969-70

Energy Technology Data Exchange (ETDEWEB)

NONE

1970-07-01

Civilization depends largely on man's ability to change and control his natural environment - and thus on the energy at his disposal. Until the industrial revolution man depended mainly on his own hands and his domestic animals, but in the last two centuries the tempo of man-made environmental change has constantly quickened. For almost every new benefit of technology, some price has had to be paid in terms of environmental side effects. In the first century of the industrial revolution, smoke and grime poured from the chimneys of the new foundries, factories and gas works. Industrial progress has helped to clear the air of some of these pollutants, but has also brought new ones in their stead.

Laboratory controlled quantitative information about reduction in air pollution using the "Basa njengo Magogo" methodology and applicability to low-smoke fuels

CSIR Research Space (South Africa)

Le Roux, Lukas J

2005-01-01

Full Text Available / M J ) 2005 Time to cooking temperature C o a l ( t r a d i t i o n a l ) C o a l ( B N M ) A n t h r a c i t e U G S l a t e r c o a l A n t h r a c i t e O C 0 5 10 15 20... the problem – Electrification – Low smoke fuels – Low smoke appliances – Basa Njengo Magogo 2005 First: add coal 2005 Second: add paper 2005 Third: add wood and extra coal 2005 First 10 minutes with chimney •BNM method •Traditional method 2005 Fuel...

Cognitive spectrum of the social mission of the rehabilitation park

Directory of Open Access Journals (Sweden)

E. G. Pozdnyakova-Kirbyateva

2017-08-01

It is emphasized that reflection on these requests exceeds the social rehabilitation of the park’s mission within cognitive umbrellas. Six peaks of logically combining achieve the same number of subjects or groups of the latter. Continuous and dashed bar side, combining the top chimney in the middle to form eight triangles. Four of the past, for example, continuous parties combine discipline with which to achieve the main objectives of the study. This position caused the author to include rationale for the creation and operation of the pilot facility for Ukraine as rehabilitation park scientific and practical achievements of social, medical, educational, architectural, psychological disciplines and ethics. Accordingly, the principles of anthropocentrism, humanism, behaviorism conceptual definition of the publication.

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.

Building materials. Stichwort Baustoff

Energy Technology Data Exchange (ETDEWEB)

Rohwer, W

1981-01-01

To handle building materials properly, one must know about their characteristics. This pocket book will be of help: structured like a glossary, it gives brief descriptions of the most common building materials. It is small and handy enough to be a constant companion to resident engineers, foremen, gangers, building tradesmen, and construction workers and an aid in their training. The following groups of building materials are discussed: Natural stone; units for brick walls, floors, and roofs; mortar and concrete (definitions, binders, aggregates, additives, admixtures, mixing water); special types of plaster and rendering; light-weight building boards and wood wool basis; multilayer light-weight building boards; gypsum plasterboards; chimney construction; sewers; thermal insulation and sound section; structural steels; plastics.

Nuclear Energy and the Environment. Addendum to the Agency's Report to the Economic and Social Council of the United Nations for 1969-70

International Nuclear Information System (INIS)

1970-01-01

Civilization depends largely on man's ability to change and control his natural environment - and thus on the energy at his disposal. Until the industrial revolution man depended mainly on his own hands and his domestic animals, but in the last two centuries the tempo of man-made environmental change has constantly quickened. For almost every new benefit of technology, some price has had to be paid in terms of environmental side effects. In the first century of the industrial revolution, smoke and grime poured from the chimneys of the new foundries, factories and gas works. Industrial progress has helped to clear the air of some of these pollutants, but has also brought new ones in their stead.

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)

1998-08-01

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

A review of the history, epidemiology and treatment of squamous cell carcinoma of the scrotum

Directory of Open Access Journals (Sweden)

Jerome Azike

2009-07-01

Full Text Available Squamous cell carcinoma of the scrotum is a tumor that is of interest for clinical and historical reasons. It was the first cancer linked to occupational exposure when, in 1775, Perivall Pott described it in chimney sweeps in England. Other occupations that had a preponderance of the disease included people who worked with the distillates of coal and men exposed to mineral oil. Currently, the disease is very rare and most cases are thought to result from poor hygiene and chronic irritation. Surgery with a negative resection margin offers the best hope of cure as adjunctive therapy has not proved useful. Prognosis correlates with the extent of nodal involvement.

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...... friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...... 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....

The radioactive environmental monitoring and its qualitative assessment at science city of Mianyang in 2001

International Nuclear Information System (INIS)

Ruan Guanglin; Xing Shixiong; Liao Xiaohua; Chang Zheng; Yang Fan

2003-01-01

The results of environmental monitoring shows that the radioactive level within main mediums (river water, air, soil and fallout etc.) have no significant differences from the background level before the start of operation of Science City of Mianyang. Through measurement and evaluation to emission of nuclear facilities, the data of sources terms are obtained. The distribution of doses in coordinate of reference are calculated by the principle of does fold to multi-chimney exhaust and air-diffuse model at the area. Quality assessments of radiological environment shows that maximum individual effective does is 4/10 5 of does limit, detriment is 2/10 7 of detriment constraint within 80 km. It is shown that environmental impact is little and receivable to the public. (authors)

An automated miniature robotic vehicle inspection system

Energy Technology Data Exchange (ETDEWEB)

Dobie, Gordon; Summan, Rahul; MacLeod, Charles; Pierce, Gareth; Galbraith, Walter [Centre for Ultrasonic Engineering, University of Strathclyde, 204 George Street, Glasgow, G1 1XW (United Kingdom)

2014-02-18

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.

An automated miniature robotic vehicle inspection system

International Nuclear Information System (INIS)

Dobie, Gordon; Summan, Rahul; MacLeod, Charles; Pierce, Gareth; Galbraith, Walter

2014-01-01

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

Verification of Conditions for use of Combustion Products‘ Heat

Directory of Open Access Journals (Sweden)

Kažimírová Viera

2015-06-01

Full Text Available Presented contribution deals with the verification of conditions for use of combustion products‘ heat, generated by combustion of wood in a fireplace used in a household. It is necessary to know the temperature behaviour of the fireplace to determine the adequacy of the technical solution for using combustion products‘ heat. The combustion products‘ temperature at the upper part of the chimney is 80-120 °C. The dew point value was established to be below 51 °C. The average observed value of combustion product velocity is 1.6 m s-1. The volume flow rate of combustion products is 12 m3 h-1. Measured values allow for effective solution of the use of combustion products‘ heat.

Desulphurization and denitrification processes in the energy industry

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Virèíková Edita

1998-09-01

Full Text Available The world´s problem of environmental pollution is also an important problem in the Slovak Republic. One of the biggest sources of air pollution is the combustion of low quality fossil fuels. During the burning of coal, combustible types of sulfur, like organic and pyritic, are oxidized and form sulfur dioxide or trioxide. Nitrogen oxides in chimney gases are generally found in three forms: NO, NO2 and N2O. It is more difficult to remove NOX than SO2 because of the structure of NOx. For this reason it is necesary to keep lower NOx emissions in the system by various methods. This paper surveys the current status of the desulphurization and denitrification processes in the energy industry.

Civil engineering in power plant technology

International Nuclear Information System (INIS)

Krolewski, H.

1982-01-01

Guaranteeing our power supplies requires increasingly large, bold or novel construction works (for example, 200 m chimney with installation of stays over a wide area for a wind power plant in Spain; up to 400 m structure height on floating drill rigs). The layman admires the impressiveness with which these demand great ability and responsibility on the part of the civil engineer. The inland power station builder has to concentrate on few spectacular methods of construction or dimensions. The success of the total undertaking is however no less attributable to structural prerequisites. Civil engineering problems have to be displaced by means of static and dynamic problems in order to meet licensing requirements (planning of construction supervision, fire prevention, structure of supply and disposal). (orig.) [de

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.

Interpreting the chemical results of the Gasbuggy experiment

International Nuclear Information System (INIS)

Taylor, R.W.; Lee, E.L.; Hill, J.H.

1970-01-01

Nuclear explosions in carbonate-bearing rocks release large amounts of CO 2 . In some cases, for example, when the explosion is contained and dolomite is the principal carbonate mineral, sufficient CO 2 may be generated to drive the formation gas away from the chimney. Rocks which contain free carbon, such as the shales of the recent Gasbuggy and proposed Bronco and Dragon Trail experiments, will liberate CO and H 2 in amounts predicted from the yield of the explosive and the C, CO 2 and H 2 O concentration in the rock. In general, the greater the amount of free carbon in a rock, the more H 2 will be produced and the higher will be the fraction of tritium in the gas phase. (author)

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.

Chimney emissions from small-scale burning of pellets and fuelwood - examples referring to different combustion appliances

International Nuclear Information System (INIS)

Kjaellstrand, Jennica; Olsson, Maria

2004-01-01

Most wood boilers used for residential heating today are old-fashioned and emit large quantities of organic compounds. The installation of a pellet burner and a change to wood pellets as fuel normally decreases the emissions remarkably. In this study, the emissions from different equipment for burning of wood and pellets are compared. The organic fraction of smoke from traditional wood burning is to a great extent composed of methoxyphenols, with antioxidant effects. Methoxyphenols were also identified in smoke from pellet stoves. A fuel wood boiler or a furnace with an inserted pellet burner is heated to a higher combustion temperature, decreasing the total amount of organic compounds in the smoke. Above 800 deg C, methoxyphenols are thermally decomposed and carcinogenic polycyclic aromatic compounds (PACs) are formed. The combustion-formed aromatic hydrocarbon benzene is present in smoke from all kinds of burning, but the proportion relative to primary organic compounds increases with increasing combustion temperature. In smoke from an environmentally labelled wood boiler and from some pellet burning devices, the levels of PAC and benzene were found to be low. Evidently, the combustion was nearly complete. Although the change from wood to pellets significantly decreases the emissions, considerable differences exist between various combinations of pellet burners and boiler furnaces. (Author)

Gas chimney detection based on improving the performance of combined multilayer perceptron and support vector classifier

NARCIS (Netherlands)

Hashemi, H.; Tax, D.M.J.; Duin, R.P.W.; Javaherian, A.; De Groot, P.

2008-01-01

Seismic object detection is a relatively new field in which 3-D bodies are visualized and spatial relationships between objects of different origins are studied in order to extract geologic information. In this paper, we propose a method for finding an optimal classifier with the help of a

Cutaneous melanoma: hints from occupational risks by anatomic site in Swedish men

Science.gov (United States)

Perez-Gomez, B; Pollan, M; Gustavsson, P; Plato, N; Aragones, N; Lopez-Abente, G

2004-01-01

Aims: To improve knowledge of the epidemiology of melanoma by comparing occupational risks of cutaneous melanoma (CM) by anatomic site in Swedish workers. Methods: Male workers employed in 1970 and living in the country in 1960 were followed up from 1971 to 1989 using the Swedish Registers of Death and Cancer. A more specifically exposed subcohort included men reporting the same occupation in 1960 and 1970. For each location, occupational risk ratios (RRs) were extracted from Poisson regression models adjusted by age, period, town size, and geographical area. To diminish the influence of socioeconomic factors, intrasector analyses, comparing only jobs belonging to the same occupational sector, were performed. Risk patterns for different locations were compared. Results: High RRs for different sites were found among workers exposed to UV sources (dentists, physiotherapists, and lithographers), and sun exposed workers (harbour masters, and lighthouse/related work). Risk excesses were seen in fur tailors, tanners/fur dressers, patternmakers/cutters, electrical fitters/wiremen, telephone/telegraph installers/repairmen, and some glass/pottery/tile workers. Results for lower and upper limbs were significantly correlated but somewhat independent of those found in thorax, the most frequent location. Correlation between head/neck and thorax was moderate. Specific risk excesses were found for rolling mill workers in head/neck, for chimney sweeps in upper limbs, and for aircraft pilots/navigators/flight engineers in lower limbs. Conclusions: High RRs in the trunk among occupations with UV exposure from artificial sources suggest an effect not restricted to exposed sites. An unusual distribution of cases and RRs in chimney sweeps, rolling-mill, or glass/pottery/tile workers suggests local effects of exposures. The not previously reported risk excess in this job and in fur related processes, and the RR in electrical fitters and telephone/telegraph installers deserve further

A dendritic solidification experiment under large gravity - implications for the Earth's inner core solidification regime.

Science.gov (United States)

Deguen, R.; Alboussière, T.; Brito, D.; La Rizza, P.; Masson, J.

2009-05-01

The Earth's inner core solidification regime is usually thought to be dendritic, which should results in the formation of a mushy layer at the inner core boundary, possibly extending deep in the inner core. The release of latent heat and solute associated with crystallization provides an important boyancy source to drive thermo- chemical convection in the core. In the laboratory, two modes of convection associated with the crystallization of mushy layers have been observed. One is a boundary layer mode originating from the destabilisation of the chemical boundary layer present at the mush-liquid interface; the second is the so-called 'mushy layer mode' which involves the whole mushy layer. In the mushy layer mode, convection usually takes the form of narrow plumes rising through crystal free conduits called chimneys. One particularity of inner core crystallization is its extremely small solidification rate compared to typical outer core convective timescales. We have designed and build an experiment devoted to the study of crystallization under a large gravity field, using a centrifuge, of an aqueous solution of ammonium chloride, which is a good analogue to metallic alloys. The large gravity field allows to reach Rayleigh numbers much larger than in typical solidification experiments. Under large gravity fields, we observe the disappearance of chimney convection and show that the large gravity field promotes the boundary layer convection mode at the expent of the mushy layer mode. As the gravitationnal forcing is increased, convective heat and solute transport are significantly enhanced, which results in larger solid fraction directly below the mush-liquid interface. The increase in solid fraction results in a dramatic decrease of the permeability in the mushy layer, which eventually becomes subcritical in respect to the mushy layer mode. Because of the very slow solidification rate of the inner core, convective transport of heat and solute from the ICB is

Physiological differentiation within a single-species biofilm fueled by serpentinization.

Science.gov (United States)

Brazelton, William J; Mehta, Mausmi P; Kelley, Deborah S; Baross, John A

2011-01-01

Carbonate chimneys at the Lost City hydrothermal field are coated in biofilms dominated by a single phylotype of archaea known as Lost City Methanosarcinales. In this study, we have detected surprising physiological complexity in single-species biofilms, which is typically indicative of multispecies biofilm communities. Multiple cell morphologies were visible within the biofilms by transmission electron microscopy, and some cells contained intracellular membranes that may facilitate methane oxidation. Both methane production and oxidation were detected at 70 to 80°C and pH 9 to 10 in samples containing the single-species biofilms. Both processes were stimulated by the presence of hydrogen (H(2)), indicating that methane production and oxidation are part of a syntrophic interaction. Metagenomic data included a sequence encoding AMP-forming acetyl coenzyme A synthetase, indicating that acetate may play a role in the methane-cycling syntrophy. A wide range of nitrogen fixation genes were also identified, many of which were likely acquired via lateral gene transfer (LGT). Our results indicate that cells within these single-species biofilms may have differentiated into multiple physiological roles to form multicellular communities linked by metabolic interactions and LGT. Communities similar to these Lost City biofilms are likely to have existed early in the evolution of life, and we discuss how the multicellular characteristics of ancient hydrogen-fueled biofilm communities could have stimulated ecological diversification, as well as unity of biochemistry, during the earliest stages of cellular evolution. Our previous work at the Lost City hydrothermal field has shown that its carbonate chimneys host microbial biofilms dominated by a single uncultivated "species" of archaea. In this paper, we integrate evidence from these previous studies with new data on the metabolic activity and cellular morphology of these archaeal biofilms. We conclude that the archaeal biofilm

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

Preliminary characterization and biological reduction of putative biogenic iron oxides (BIOS) from the Tonga-Kermadec Arc, southwest Pacific Ocean.

Science.gov (United States)

Langley, S; Igric, P; Takahashi, Y; Sakai, Y; Fortin, D; Hannington, M D; Schwarz-Schampera, U

2009-01-01

Sediment samples were obtained from areas of diffuse hydrothermal venting along the seabed in the Tonga sector of the Tonga-Kermadec Arc, southwest Pacific Ocean. Sediments from Volcano 1 and Volcano 19 were analyzed by X-ray diffraction (XRD) and found to be composed primarily of the iron oxyhydroxide mineral, two-line ferrihydrite. XRD also suggested the possible presence of minor amounts of more ordered iron (hydr)oxides (including six-line ferrihydrite, goethite/lepidocrocite and magnetite) in the biogenic iron oxides (BIOS) from Volcano 1; however, Mössbauer spectroscopy failed to detect any mineral phases more crystalline than two-line ferrihydrite. The minerals were precipitated on the surfaces of abundant filamentous microbial structures. Morphologically, some of these structures were similar in appearance to the known iron-oxidizing genus Mariprofundus spp., suggesting that the sediments are composed of biogenic iron oxides. At Volcano 19, an areally extensive, active vent field, the microbial cells appeared to be responsible for the formation of cohesive chimney-like structures of iron oxyhydroxide, 2-3 m in height, whereas at Volcano 1, an older vent field, no chimney-like structures were apparent. Iron reduction of the sediment material (i.e. BIOS) by Shewanella putrefaciens CN32 was measured, in vitro, as the ratio of [total Fe(II)]:[total Fe]. From this parameter, reduction rates were calculated for Volcano 1 BIOS (0.0521 day(-1)), Volcano 19 BIOS (0.0473 day(-1)), and hydrous ferric oxide, a synthetic two-line ferrihydrite (0.0224 day(-1)). Sediments from both BIOS sites were more easily reduced than synthetic ferrihydrite, which suggests that the decrease in effective surface area of the minerals within the sediments (due to the presence of the organic component) does not inhibit subsequent microbial reduction. These results indicate that natural, marine BIOS are easily reduced in the presence of dissimilatory iron-reducing bacteria, and that the

XRF analysis of soils contaminated by dust falls

International Nuclear Information System (INIS)

Marumo, Katsumi; Onoki, Yuka; Wada, Nobuhiko; Okano, Hideki

2013-01-01

Dust falls from the chimneys of waste incineration plants, coal-fired power plants, and refineries may contaminate soil over vast areas. Using an auger machine at 72 sites around a refinery in the Kanto area, Japan, we obtained 216 soil samples for a screening survey of potentially contaminated land. Qualitative and quantitative chemical analyses of zinc, lead, and cadmium were performed using a transmission X-ray fluorescence spectrometer (TXRF). X-ray fluorescence (XRF) chemical analytical data suggested that contaminated soil extends up to 3 km away from the chimneys of the refinery. Using calibration curves for the intensity ratios of Zn Kα X-ray to Mo Kβ Compton scatter X-ray [(Zn Kα)/(Mo-Kβ-Compton)], Pb Lβ X-ray to Mo-Kβ-Compton scatter X-ray [(Pb Lβ)/(Mo-Kβ-Compton)], and Cd Kα X-ray to Mo-Kβ Compton scatter X-ray [(Cd Kβ)/(Mo-Kβ-Compton)] of 30 reference materials, we obtained the Zn, Pb, and Cd concentrations of these 216 soil samples. The Pb and Cd concentrations from the XRF chemical analytical data were very similar to the Pb and Cd leachabilities determined by 1 M HC1 leaching test (MOE-approved method No. 19), suggesting that the chemical forms in which Pb and Cd occur are an adsorbed phase and a carbonate phase, which can be easily dissolved by 1 M HC1. XRF spectra of individual soil particles, obtained by spot-sized X-ray beams passed through a 1.5-mm-diameter and a 0.5-mm-diameter collimators, suggested that most of the soil fractions contained Zn and Pb. The levels of brightness of the X-ray images of these Zn- and Pb-bearing fractions were monitored with an X-ray CCD camera attached to the TXRF. Most of the soil fractions were transparent at the maximum X-ray tube voltage (50 kV), suggesting that the soil samples are suitable for the quantitative XRF chemical analysis of Zn and Pb. (author)

Diversity of meiofauna from the 9°50'N East Pacific rise across a gradient of hydrothermal fluid emissions.

Directory of Open Access Journals (Sweden)

Sabine Gollner

2010-08-01

Full Text Available We studied the meiofauna community at deep-sea hydrothermal vents along a gradient of vent fluid emissions in the axial summit trought (AST of the East Pacific Rise 9°50'N region. The gradient ranged from extreme high temperatures, high sulfide concentrations, and low pH at sulfide chimneys to ambient deep-sea water conditions on bare basalt. We explore meiofauna diversity and abundance, and discuss its possible underlying ecological and evolutionary processes.After sampling in five physico-chemically different habitats, the meiofauna was sorted, counted and classified. Abundances were low at all sites. A total of 52 species were identified at vent habitats. The vent community was dominated by hard substrate generalists that also lived on bare basalt at ambient deep-sea temperature in the axial summit trough (AST generalists. Some vent species were restricted to a specific vent habitat (vent specialists, but others occurred over a wide range of physico-chemical conditions (vent generalists. Additionally, 35 species were only found on cold bare basalt (basalt specialists. At vent sites, species richness and diversity clearly increased with decreasing influence of vent fluid emissions from extreme flow sulfide chimney (no fauna, high flow pompei worm (S: 4-7, H'(loge: 0.11-0.45, vigorous flow tubeworm (S: 8-23; H'(loge: 0.44-2.00 to low flow mussel habitats (S: 28-31; H'(loge: 2.34-2.60.Our data suggest that with increasing temperature and toxic hydrogen sulfide concentrations and increasing amplitude of variation of these factors, fewer species are able to cope with these extreme conditions. This results in less diverse communities in more extreme habitats. The finding of many species being present at sites with and without vent fluid emissions points to a non endemic deep-sea hydrothermal vent meiofaunal community. This is in contrast to a mostly endemic macrofauna but similar to what is known for meiofauna from shallow-water vents.

Your house shouldn't kill you : why knowledge of building science is important

Energy Technology Data Exchange (ETDEWEB)

Anon.

2006-05-15

A carbon monoxide (CO) poisoning death in British Columbia in 1999 was used as a case study to examine errors and faults in Canadian construction practices. The main source of CO was from an over-fired propane boiler that spilled combustion products when the house's chimney failed to establish a proper draft. The heating system was a high-efficiency condensing propane forced air furnace. Basement in-slab radiant heating floor panels were heated by a B-vented draft hood equipped boiler. Although properly installed, one of the compounding effects allowing the CO to enter the living space was the cold B-vent serving the boiler, which reversed itself and became an additional air inlet. Depressurization in the furnace room was enhanced by the leaky furnace ducts and by the stack action in the house. The house was located at 2760 feet above sea level, and it was noted that many gas-fired appliances must be derated when used at 2000 feet in elevation. Additionally, some appliances must be derated from their natural gas ratings when units are fired by propane. It was also noted that the owner of the house returned after a prolonged absence, and turned the thermostat up to 30 degrees C, which meant that the heating system was firing much longer than if it had been set to 22 degrees C. After the post-mortem, the coroner's report recommended that return air leakage should be minimized; there should never be a cold chimney located largely outside the heated envelope of the house; a garage should not be heated with a home's forced air system as compensating make-up air is needed; and, make-up should be provided when there is a naturally vented combustion appliance in the house. It was also recommended that all new houses be equipped with a CO detector. 3 figs.

Fine particles and carbon monoxide from wood burning in 17th-19th century Danish kitchens: Measurements at two reconstructed farm houses at the Lejre Historical-Archaeological Experimental Center

Science.gov (United States)

Ryhl-Svendsen, Morten; Clausen, Geo; Chowdhury, Zohir; Smith, Kirk R.

2010-02-01

Carbon monoxide (CO) and particulate matter (PM 2.5) were measured in two reconstructed Danish farmhouses (17-19th century) during two weeks of summer. During the first week intensive measurements were performed while test cooking fires were burned, during the second week the houses were monitored while occupied by guest families. A masonry hearth was located in the middle of each house for open cooking fires and with heating stoves. One house had a chimney leading to the outside over the hearth; in the other, a brickwork hood led the smoke into an attic and through holes in the roof. During the first week the concentration of PM 2.5 averaged daily between 138 and 1650 μg m -3 inside the hearths and 21-160 μg m -3 in adjacent living rooms. CO averaged daily between 0.21 and 1.9 ppm in living areas, and up to 12 ppm in the hearths. Highest concentrations were measured when two fires were lit at the same time, which would cause high personal exposure for someone working in the kitchens. 15 min averages of up to 25 400 μg m -3 (PM 2.5) and 260 ppm CO were recorded. WHO air quality guidelines were occasionally exceeded for CO and constantly for PM 2.5. However, air exchange and air distribution measurements revealed a large draw in the chimney, which ensured a fast removal of wood smoke from the hearth area. The guest families were in average exposed to no more than 0.21 ppm CO during 48 h. Based on a hypothetical time-activity pattern, however, a woman living in this type of house during the 17-19th century would be exposed to daily averages of 1.1 ppm CO and 196 μg m -3 PM 2.5, which exceeds WHO guideline for PM 2.5, and is comparable to what is today observed for women in rural areas of developing countries.

Is high-pressure water the cradle of life?

International Nuclear Information System (INIS)

Bassez, Marie-Paule

2003-01-01

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)

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...

Heat exchanger for cooling a liquid metal with air, including panels of identical tubes

International Nuclear Information System (INIS)

Malaval, C.

1985-01-01

The heat exchanger includes panels of identical tubes, each one comprising two horizontal collectors situated at the vertical of each other and a group of vertical tubes for cooling arranged in a horizontal parallelepiped casing opened on two of its opposite sides. The air flows from the inlet to the outlet face of the casing. The panels of tubes are arranged side by side so that their outlet faces form a prismatic surface of which the height is vertical and the inner space communicates with a vertical axis chimney. Each one of the panels is hanging from a fixed structure by means of articulated fasteners, by means of its upper collector only. The invention applies, more particularly, for cooling the primary sodium of fast neutron reactors after they are stopped [fr

Economic aspects of Solar Thermal Technologies for electricity generation

International Nuclear Information System (INIS)

Meinecke, W.

1993-01-01

Economic results of German studies are presented, which compare the four solar thermal technologies for electricity generation (parabolic trough collector system, central receiver system, parabolic dish/Stirling system, solar chimney plant). These studies were carried out by Interatom (today Siemens/KWU) in Bergisch Gladbach, Flachglas Solartechnik in Koln and Schlaich Bergermann and Partner in Stuggart under contract of DLR in Koln. Funds were made available by the German Ministry of Research and Development (BMFT). The results indicate that all of the investigated technologies have the potential to reduce the generating costs and that in the future costs of below 0.30 DM/kWh could be expected under excellent insolation conditions (e.G. 2850 kWh/m''2 a direct insolation as in California/USA). (Author) 25 refs

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.)

Seismic vulnerability assessment of chemical plants through probabilistic neural networks

International Nuclear Information System (INIS)

Aoki, T.; Ceravolo, R.; De Stefano, A.; Genovese, C.; Sabia, D.

2002-01-01

A chemical industrial plant represents a sensitive presence in a region and, in case of severe damage due to earthquake actions, its impact on social life and environment can be devastating. From the structural point of view, chemical plants count a number of recurrent elements, which are classifiable in a discrete set of typological families (towers, chimneys, cylindrical or spherical or prismatic tanks, pipes etc.). The final aim of this work is to outline a general procedure to be followed in order to assign a seismic vulnerability estimate to each element of the various typological families. In this paper, F.E. simulations allowed to create a training set, which has been used to train a probabilistic neural system. A sample application has concerned the seismic vulnerability of simple spherical tanks

Pollutant emissions of commercial and industrial wood furnaces

International Nuclear Information System (INIS)

Baumbach, G.; Angerer, M.

1993-03-01

Based on literature surveys, personal contacts to designers, manufactures and users of woold furnaces, as well as informations of experts from Austria and Switzerland, the used wood fuels and combustion techniques and the potentially by commercial and industrial wood burning emitted air pollutants are described; including the mechanism of pollutant formation, concentrations, and their environmental relevance. The actual situation in Baden-Wuerttemberg concerning the used wood fuels, the state of installed and operated furnaces and the amount of emitted pollutants is presented basing on informations of the 'Statistical Country Bureau' and a country-wide inquiry round the chimney-sweepers. In order to realize the described existing possibilities to reduce pollutant emissions the introduction of a general brand test and certification mode is proposed. (orig.). 53 figs., 118 refs [de

Analytical model for transient fluid mixing in upper outlet plenum of an LMFBR

International Nuclear Information System (INIS)

Yang, J.W.; Agrawal, A.K.

1976-01-01

A two-zone mixing model based on the lumped-parameter approach was developed for the analysis of transient thermal response in the outlet plenum of an LMFBR. The maximum penetration of core flow is used as the criterion for dividing the sodium region into two mixing zones. The model considers the transient sodium temperature affected by the thermal expansion of sodium, heat transfer with cover gas, heat capacity of different sections of metal and the addition of by-pass flow into the plenum. The results of numerical calculations indicate that effects of flow stratification, chimney height, metal heat capacity and by-pass flow are important for transient sodium temperature calculation. Thermal expansion of sodium and heat transfer with the cover gas do not play any significant role on sodium temperature

Interpreting the chemical results of the Gasbuggy experiment

Energy Technology Data Exchange (ETDEWEB)

Taylor, R W; Lee, E L; Hill, J H [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-01

Nuclear explosions in carbonate-bearing rocks release large amounts of CO{sub 2}. In some cases, for example, when the explosion is contained and dolomite is the principal carbonate mineral, sufficient CO{sub 2} may be generated to drive the formation gas away from the chimney. Rocks which contain free carbon, such as the shales of the recent Gasbuggy and proposed Bronco and Dragon Trail experiments, will liberate CO and H{sub 2} in amounts predicted from the yield of the explosive and the C, CO{sub 2} and H{sub 2}O concentration in the rock. In general, the greater the amount of free carbon in a rock, the more H{sub 2} will be produced and the higher will be the fraction of tritium in the gas phase. (author)

Theseus: tethered distributed robotics (TDR)

Science.gov (United States)

Digney, Bruce L.; Penzes, Steven G.

2003-09-01

The Defence Research and Development Canada's (DRDC) Autonomous Intelligent System's program conducts research to increase the independence and effectiveness of military vehicles and systems. DRDC-Suffield's Autonomous Land Systems (ALS) is creating new concept vehicles and autonomous control systems for use in outdoor areas, urban streets, urban interiors and urban subspaces. This paper will first give an overview of the ALS program and then give a specific description of the work being done for mobility in urban subspaces. Discussed will be the Theseus: Thethered Distributed Robotics (TDR) system, which will not only manage an unavoidable tether but exploit it for mobility and navigation. Also discussed will be the prototype robot called the Hedgehog, which uses conformal 3D mobility in ducts, sewer pipes, collapsed rubble voids and chimneys.

SOLAR RADIATION ESTIMATION ON BUILDING ROOFS AND WEB-BASED SOLAR CADASTRE

Directory of Open Access Journals (Sweden)

G. Agugiaro

2012-07-01

Full Text Available 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.

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

Knowledge of cancer risk according to occupational affiliation is an essential part of formatting preventive actions aimed at the adult population. Herein, data on 10 major cancer sites amenable by life style exposures from the Nordic Occupational Cancer Study (NOCCA) are presented. All subjects...... 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...

Fatigue in Steel Structures under Random Loading

DEFF Research Database (Denmark)

Agerskov, Henning

1999-01-01

types of welded plate test specimens and full-scale offshore tubular joints. The materials that have been used are either conventional structural steel with a yield stress of ~ 360-410 MPa or high-strength steel with a yield stress of ~ 810-1010 MPa. The fatigue tests and the fracture mechanics analyses......Fatigue damage accumulation in steel structures under random loading is studied. The fatigue life of welded joints has been determined both experimentally and from a fracture mechanics analysis. In the experimental part of the investigation, fatigue test series have been carried through on various...... have been carried out using load histories, which are realistic in relation to the types of structures studied, i.e. primarily bridges, offshore structures and chimneys. In general, the test series carried through show a significant difference between constant amplitude and variable amplitude fatigue...

Seasonal fluctuations of the uranium and thorium contents in aerosols in surface air

International Nuclear Information System (INIS)

Kolb, W.

1985-01-01

An estimate in the UNSCEAR report the only source considered for the uranium and thorium contents is ground dust. A significant portion of the aerosols, however, comes from chimneys. Aerosol samples taken monthly in Brunswick, Berlin, Skibotn (Northern Norway) were, therefore, scrutinized alpha-spectrometrically for U-238, U-234, Th-230, and Th-232. The activity concentration in surface air of Northern Norway is only about 30 nBq/cm 3 . In Brunswick and Berlin, the concentration was higher by a factor of one to two due to the higher specific activity of the mineral aerosols. Significant differences of the isotope ratios allow conclusions as to the origin of the aerosols. The activity concentrations measured and their seasonal fluctuations must be taken into account in the evaluation of environment monitoring of nuclear fuel factories. (orig./HP) [de

A study of the distribution of rare-metals in kuroko-type ore

International Nuclear Information System (INIS)

Murao, S.; Sie, S.H.; Suter, G.F.

1996-01-01

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

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.

The Fatigue Behavior of Steel Structures under Random Loading

DEFF Research Database (Denmark)

Agerskov, Henning

2009-01-01

of the investigation, fatigue test series with a total of 540 fatigue tests have been carried through on various types of welded plate test specimens and full-scale offshore tubular joints. The materials that have been used are either conventional structural steel or high-strength steel. The fatigue tests......Fatigue damage accumulation in steel structures under random loading has been studied in a number of investigations at the Technical University of Denmark. The fatigue life of welded joints has been determined both experimentally and from a fracture mechanics analysis. In the experimental part...... and the fracture mechanics analyses have been carried out using load histories, which are realistic in relation to the types of structures studied, i.e. primarily bridges, offshore structures and chimneys. In general, the test series carried through show a significant difference between constant amplitude...

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

1997-12-31

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.

Unusually amplified summer or winter indoor levels of radon

International Nuclear Information System (INIS)

Gammage, R.B.; Dudney, C.S.; Wilson, D.L.

1993-01-01

The ratios of winter/summer indoor radon levels for houses in different regions of the southern Appalachians are characterized by individual log-normal distributions with geometric means both above and below unity. In some counties and cities, subpopulations of houses have unusually exaggerated winter/summer ratios of indoor radon, as well as high indoor radon levels, during periods of either warm or cool weather. It is proposed that in many instances, houses are communicating with larger than normal underground reservoirs of radon-bearing air in hilly karst terrains; differences between the outdoor and underground air temperatures are believed to provide density gradients producing aerostatic pressure differences for seasonally directed underground transport and subsequently elevated indoor radon. These seasonal movements of air are analogous to the well-known underground chimney effects, which produce interzonal flows of air inside caves

Mixing of two-component flow in a simplified stirred tank with cellular automaton method; Cellular automaton ho ni yoru kakuhan sonai no niseibunryu no kongo keisan

Energy Technology Data Exchange (ETDEWEB)

Watanabe, S; Takahashi, R [Tokyo Institute of Technology, Tokyo (Japan)

1996-01-25

The applicability of a cellular automaton technique to engineering problems will be examined by dealing with mixing in multicomponent flow. The quality and accumulation rate of the product depend on the mixing of raw materials basically. After thoroughly understanding the mixing process, we optimize the geometrical allocation of such elements as a propeller with casing, a chimney and a product output nozzle in a reactor. Usually mixing is formulated by partial differential equations of conservation laws and empirical formulae, and solved numerically by the finite difference technique. In order to evaluate the fine structure of time-dependent interfacial behavior in multicomponent flow, the cellular automaton technique is used, since this has an advantage of describing the pattern formation in detail. It will be demonstrated in the present paper that mixing of two-component immiscible flow is reasonably simulated mesoscopically. 13 refs., 17 figs.

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.

Seabed fluid expulsion along the upper slope and outer shelf of the U.S. Atlantic continental margin

Science.gov (United States)

Brothers, D.S.; Ruppel, C.; Kluesner, J.W.; ten Brink, Uri S.; Chaytor, J.D.; Hill, J.C.; Andrews, B.D.; Flores, C.

2014-01-01

Identifying the spatial distribution of seabed fluid expulsion features is crucial for understanding the substrate plumbing system of any continental margin. A 1100 km stretch of the U.S. Atlantic margin contains more than 5000 pockmarks at water depths of 120 m (shelf edge) to 700 m (upper slope), mostly updip of the contemporary gas hydrate stability zone (GHSZ). Advanced attribute analyses of high-resolution multichannel seismic reflection data reveal gas-charged sediment and probable fluid chimneys beneath pockmark fields. A series of enhanced reflectors, inferred to represent hydrate-bearing sediments, occur within the GHSZ. Differential sediment loading at the shelf edge and warming-induced gas hydrate dissociation along the upper slope are the proposed mechanisms that led to transient changes in substrate pore fluid overpressure, vertical fluid/gas migration, and pockmark formation.

Environment pollution with aluminium around a coalburning electric power plant

International Nuclear Information System (INIS)

Hermann, J.

1997-01-01

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)

Site selection

International Nuclear Information System (INIS)

Olsen, C.W.

1983-07-01

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 CO 2 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

Subsurface Noble Gas Sampling Manual

Energy Technology Data Exchange (ETDEWEB)

Carrigan, C. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sun, Y. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-09-18

The intent of this document is to provide information about best available approaches for performing subsurface soil gas sampling during an On Site Inspection or OSI. This information is based on field sampling experiments, computer simulations and data from the NA-22 Noble Gas Signature Experiment Test Bed at the Nevada Nuclear Security Site (NNSS). The approaches should optimize the gas concentration from the subsurface cavity or chimney regime while simultaneously minimizing the potential for atmospheric radioxenon and near-surface Argon-37 contamination. Where possible, we quantitatively assess differences in sampling practices for the same sets of environmental conditions. We recognize that all sampling scenarios cannot be addressed. However, if this document helps to inform the intuition of the reader about addressing the challenges resulting from the inevitable deviations from the scenario assumed here, it will have achieved its goal.

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.

On morphology of methane-derived authigenic carbonates

Science.gov (United States)

Logvina, E.; Matveeva, T.

2009-04-01

Studies of methane-derived carbonates revealed a great variety their morphological types. Although the processes of these carbonates formation is not clearly understood, it has been suggested that in general bacterially mediated processes of hydrocarbon oxidation, coupled with sulphate reduction, produce unusually high levels of alkalinity and dissolved inorganic carbon in the pore fluids that is partitioned between the precipitating carbonate and CO2 rich plumes which emanate into the water column (Aharon, 1994). These carbonates consist by three main CaCO3 polymorphs - calcite, aragonite and dolomite. Carbonates with different petrography cemented from these polymorphs can be classified according to their specific locality mode of formation and biogenic or non-biogenic origin (Greinert et al., 2002). There are classifications for the authigenic carbonates which are based on petrography, morphology, or based on age and origin. In this work we will consider the petrographical and morphological differences of authigenic carbonates. The large structures vary from 10 to 200 m size, named as chemoherm carbonates. Usually they cemented by pure aragonite with minor Mg-calcite admixture. These chemoherms rise up to 50 m above the seafloor. The structures are irregular in shape and have numerous pores and open pathways resulting from plumbing system of fluid expulsion. This type of authigenic carbonates was observed in the NE Black Sea (Michaelis et al., 2002), at the Hydrate Ridge area (Greinert et al., 2001), at Aleutian accretionary margin (Greinert et al., 2002). Diagenetic carbonates - carbonate cemented sediments both growing at the seafloor or within the sediment framework and showing a large variety of shapes (chimneys, crusts, concretions est.), with grey to dark-grey color. Petrographically the carbonate cement represents by Mg-calcite, protodolomite and dolomite. The diagenetic carbonates occur widely in the fluid venting areas. In particular, diagenetic

Site Characterization Data from the U3ax/bl Exploratory Boreholes at the Nevada Test Site

International Nuclear Information System (INIS)

2005-01-01

This report provides qualitative analyses and preliminary interpretations of hydrogeologic data obtained from two 45-degree, slanted exploratory boreholes drilled within the Area 3 Radioactive Waste Management Site (RWMS) at the Nevada Test Site. Borehole UE-3bl-D1 was drilled beneath the U3ax/bl mixed waste disposal unit, and Borehole UE-3bl-U1 was drilled in undisturbed alluvium adjacent to the disposal unit. The U3ax/bl disposal unit is located within two conjoined subsidence craters, U3ax and U3bl, which were created by underground nuclear testing. Data from these boreholes were collected to support site characterization activities for the U3ax/bl disposal unit and the entire Area 3 RWMS. Site characterization at disposal units within the Area 3 RWMS must address the possibility that subsidence craters and associated disturbed alluvium of the chimneys beneath the craters might serve as pathways for contaminant migration. The two boreholes were drilled and sampled to compare hydrogeologic properties of alluvium below the waste disposal unit with those of adjacent undisturbed alluvium. Whether Borehole UE-3bl-D1 actually penetrated the chimney of the U3bl crater is uncertain. Analyses of core samples showed little difference in hydrogeologic properties between the two boreholes. Important findings of this study include the following: No hazardous or radioactive constituents of waste disposal concern were found in the samples obtained from either borehole. No significant differences in physical and hydrogeologic properties between boreholes is evident, and no evidence of significant trends with depth for any of these properties was observed. The values observed are typical of sandy materials. The alluvium is dry, with volumetric water content ranging from 5.6 to 16.2 percent. Both boreholes exhibit a slight increase in water content with depth, the only such trend observed. Water potential measurements on core samples from both boreholes show a large positive