Using infra-red (IR) thermography, power loads onto the MKII Gas-Boxdivertor targets have been investigated in Type-I ELMy H-Mode plasmas at JET in medium current discharges (Ip = 2.6 MA and BT = 2.7 T). Heat fluxes are calculated from the measured divertor target tile surface temperatures taking into account the influence of co-deposited surface layers on tile surfaces. This is particularly important when estimating the energy deposition during transient events such as ELMs. Detailed energy balance analysis is used, both from IR and tile embedded thermocouples, to demonstrate an approximately constant ELM-averaged in/out divertor target asymmetry of ?0.55 and to show that the ELM in/out energy deposition ratio ranges from 1 : 1 to 2 : 1. The inter-ELM in/out ratio is close to the ELM-averaged value at low pedestal collisionalities and decreases down to values close to zero when the inner target plasma ...
On handling nitric solutions in the glove box nitrous gases are formed that are sucked off via a heated activated charcoal filter and a catalyst cartridge containing e.g. the FG 590 H catalist (Degussa). By the activated charcoal the nitrous gases are reduced to N/sub 2/ and CO gas; the catalyst will oxidize CO to CO/sub 2/. The CO/sub 2/ obtained is discharged through an exhaust air filter in the glove box.
The DITE (Divertor Injection Tokamak Experiment) program has been undertaken to demonstrate the feasibility of impurity control by the use of a diverter in an injection-heated toroidal plasma configuration. Rather than behaving in accordance with neoclassical toroidal containment theory, the plasma is subject to various instabilities, particularly the resistive fluid MHD types, follows the empirical scaling of energy confinement time with plasma parameters observed in other plasma devices. DITE experiments have, however, extended the range of current and density. Impurities arising from plasma interactions with the vacuum vessel surface are controlled by the bundle divertor, which diverts a portion of plasma and power in the plasma scrape-off layer into a separate target chamber where impurities can be removed. Auxiliary plasma heating is provided by the injection of powerful beams of neutral hydrogen atoms produced by multi-aperture ion ...
We present a large set of merger simulations of early-type disc galaxies with mass ratios of 1:1 and 3:1 and 10% of the total disc mass in gas. In contrast to the collisionless case equal-mass mergers with gas do not result in very boxy remnants which is caused by the suppression of box orbits and the change of the projected shape of minor-axis tube orbits in the more axisymmetric remnants. The isophotal shape of 3:1 remnants and the global kinematic properties of 1:1 and 3:1 remnants are only weakly affected by the presence of gas. 1:1 remnants are slowly rotating whereas 3:1 remnants are fast rotating and discy. The shape of the stellar LOSVD is strongly influenced by gas. The LOSVDs of collisionless remnants have broad leading wings while their gaseous counterparts show steep leading wings, more consistent with observations of elliptical galaxies. We show that this change is also ...
The deuterium inventory at JET after 2001-2004 operational campaign has been determined using nuclear reaction analysis (NRA) and secondary ion mass spectrometry (SIMS). A full poloidal set of divertor tiles and a set of outer poloidal limiter (OPL) tiles were analysed providing an estimation for the total deuterium retention of about 66 g. Deuterium is trapped mainly at the inner divertor on horizontal target tile and at the inner divertor louvre area where ?60% of the trapped D is found. The long-term D retention is ?4% of the total D input.
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The available measurements on the cosmic-ray antiproton/proton ratio show an excess of antiprotons above predictions derived in the framework of the standard picture of cosmic-ray origin and propagation. Calculations are performed of the production from collisions of cosmic rays with the interstellar gas under the condition of distributed reacceleration. It could be shown that the calculated antiproton/proton ratio is enhanced compared to that derived from the leaky box model, but it remains difficult to bring it into agreement with the data by reasonable astrophysical assumptions. 15 references.
A survey was undertaken of literature on the conversion of coke-fired cupola furnaces so that they can be fuelled, either wholly or partially, with natural gas. The aim was to determine the most suitable method for a specific furnace. Substitution with natural gas can result in speedier adjustment and control of the smelting process and in addition operational costs are reduced as natural gas is a cheaper fuel. The payback period would be one year. Pollutive emissions would be reduced. It was concluded that the most satisfactory solution would be that 3-4 gas burners should be placed immediately above the smelting zone in the furnace. Each burner should be placed in a separate combustion box in which the complete combustion process could take place. The burners should be placed symmetrically about the furnace, pointing at a small degree downwards. In this way the combustion chamber ...
In 1999, the plasma parameters of reversed shear (RS) plasmas had been extended in 1) DT-equivalent fusion power gain Q_D_T"e"q - 0.5 (n_D(0)#tau#_ET_i(0) - 4x10"2"0 m"-"3#centre dot#keV#centre dot#s) for 0.8 s and 2) full non-inductive current drive with 80% of the bootstrap current fraction. Physics of the internal transport barriers (ITBs) in RS plasmas, including the energy transport and the formation of ITB, were extensively studied. A nearly full current drive (92% non-inductively) was obtained with negative ion based neutral beam (NNB) injection (360 keV, 3.4 MW) in a high #beta#_p H-mode plasma (I_p=1.5 MA, B_T=3.7 T, q_9_5=4.2) with high plasma performance (#beta#_N=2.4 and H_8_9=2.56). Rise in the central electron temperature (T_e - 9 keV) resulted in the current drive efficiency #eta#_C_D of NNB reached 1.3x10"1"9 A/W/m"2, the highest for the neutral beam current drive. As for the H-mode plasmas, decrease in the pedestal ion temperature due to strong gas ...
The aim was to investigate conditions relating to the substitution of natural gas for part of the amount of cinders previously used as fuel in an existing cupola furnace used in an iron foundry. The process of retrofitting is described. The principle solution is that four gas burners are placed symmetrically around the furnace immediately above the melting zone. They are mounted in separate fire boxes in such a way that they point downwards in order to prevent the fire box being filled with materials from the furnace, which would cause damage to the burners. The burners are continuously controlled to produce an output of 720 - 2620 kW and with 0.5 - 1.5 excess air. This solution was successful although it was found necessary (in order to achieve a satisfactory quality of resulting molten material) to add extra cinders to the furnace resulting in a reduction of only 9% of total cinders used, instead of ...
A new double-null, slotted divertor configuration will be installed for the DIII-D Radiative Divertor Program at General Atomics in late 1996. Four cryocondensation pumps, three new and one existing, will be part of this new divertor. The purpose of the pumps is to provide plasma density control and to limit the impurities entering the plasma core by providing pumping at each divertor strike point. The three new pumps are based on the design of the existing pump, installed in 1992 as part of the Advanced Divertor Program. The pump continues to operate successfully. The new pumps require geometry modifications to the original design. Therefore, extensive modal and dynamic analyses were performed to determine the behavior of these pumps and their helium and nitrogen feed lines during disruption events. Thermal and fluid analyses were also performed to characterize the helium two-phase ...
A new double-null, slotted divertor configuration will be installed for the DIII-D Radiative Divertor Program at General Atomics in late 1996. Four cryocondensation pumps, three new and one existing, will be part of this new divertor. The purpose of the pumps is to provide plasma density control and to limit the impurities entering the plasma core by providing pumping at each divertor strike point. The three new pumps are based on the design of the existing pump, installed in 1992 as part of the Advanced Divertor Program. The new pumps require geometry modifications to the original design. Therefore, extensive modal and dynamic analyses were performed to determine the behavior of these pumps and their helium and nitrogen feed lines during disruption events. Thermal and fluid analyses were also performed to characterize the helium two-phase flow regime in the pumps and their ...
A new double-null, slotted divertor configuration will be installed for the DIII-D Radiative Divertor Program at General Atomics in late 1996. Four cryocondensation pumps, three new and one existing, will be part of this new divertor. The purpose of the pumps is to provide plasma density control and to limit the impurities entering the plasma core by providing pumping at each divertor strike point. The three new pumps are based on the design of the existing pump, installed in 1992 as part of the Advanced Divertor Program. The pump continues to operate successfully. The new pumps require geometry modifications to the original design. Therefore, extensive modal and dynamic analyses were performed to determine the behavior of these pumps and their helium and nitrogen feed lines during disruption events. Thermal and fluid analyses were also performed to characterize the helium two-phase ...
The paper reports the progress made by the ITER Home Teams in the development of robust carbon and tungsten armoured plasma facing components for the ITER divertor. The activities on the development and study of armour materials, joining technologies, non-destructive evaluation techniques, high heat flux testing of manufactured components and neutron irradiation resistance studies are presented. The results of these activities confirm the feasibility of the main divertor components. Examples of the fruitful collaboration between Parties and future R and D needs are also described. (author)
Several fast neutral pressure gauges have been installed on NSTX [National Spherical Torus Experiment] to measure the vessel and divertor pressure during inductive and coaxial helicity injected (CHI) plasma operations. Modified, PDX [Poloidal Divertor Experiment]-type Penning gauges have been installed on the upper and lower divertors. Neutral pressure measurements during plasma operations from these and from two shielded fast Micro ion gauges at different toroidal locations on the vessel mid-plane are described. A new unshielded ion gauge, referred to as the In-vessel Neutral Pressure (INP) gauge is under development.
Within the framework of the EU power plant conceptual study (PPCS), a modular He-cooled divertor concept with integrated pin array (HEMP) is being developed at the Forschungszentrum Karlsruhe. The design goal is to achieve a high heat flux of at least about 10-15 MW/m"2, which is proposed for a near-term reactor model like DEMO. The development and optimization of the divertor concept require a close link between the main issues: design, analyses, materials and fabrication technology, and experiments with feedbacks between them to be accounted for. Design-specific requirements on materials and fabrication issues will be discussed.
In simulations with high radiated power fractions, it is possible to produce the drop in ion current to the divertor targets typical of detached plasmas. Despite the fact that these experiments are performed on beryllium target tiles, radiation from deuterium and beryllium cannot account for the measured power losses. The neutral deuterium levels in the SOL in these plasmas are higher than the model predicts. This may be due to leakage from the divertor or to additional wall sources related to the non-steady nature of these plasmas. In contrast, a surprisingly high level of carbon is present in these discharges; higher even than would be predicted are the divertor target tiles pure carbon. This level may well be large enough to produce the measured radiation. (authors). 6 refs., 2 figs., 1 tab.
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DEXD/H-box RNA helicases couple ATP hydrolysis to RNA remodeling by an unknown mechanism. We used x-ray crystallography and biochemical analysis of the human DEXD/H-box...Full Text Available
This is a report on modification of a locomotive diesel engine to a dual-fuel engine to determine if the dual fuel engine in railway service will provide high performance, lower fuel and maintenance costs. After the locomotive was modified and the new governor and linkage were installed by General Motors at the BN's Northtown Diesel Shop near Minneapolis, the locomotive went through startup procedures. General Motors participated in startup. Some calibration, adjustments and minor piping changes were required but in general the problems encountered in startups were quite insignificant. The locomotive was connected to the load box (static test) during startup and at 720 RPM exceeded the required output for this test as established by the parties. Operation on straight oil over the range from idle through No. 8 throttle notch and on dual fuel from No. 5 through No. 8 throttle notch was smooth as was the transfer from oil to gas and from ...
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We present the design of a diagnostic system to measure electron cyclotron absorption at the second harmonic E-mode resonance in the JET pumped divertor plasma. The diagnostic will measure transmission as a function of frequency along one or more sightlines from which the spatial profile of the n_eT_e product will be deduced. The divertor is briefly described, and the electron cyclotron resonance physics relevant to this measurement is reviewed. The problems of measuring transmission using an oversized transmission system are discussed and the chosen measurement technique, a swept frequency interferometer using a coherent radiation source, is described. A prototype of the instrument has been assembled to test the measurement technique. Some data demonstrating the instrument's characteristics are presented. The nonresonant losses, which may affect the interpretation of the measurement, are also discussed. (orig.).
The divertor 'Large Project' was conceived with the aim of demonstrating the feasibility of meeting the lifetime requirements by employing the candidate armor materials of beryllium, tungsten (W) and carbon-fiber-composite (CFC). At the start, there existed only limited experience with constructing water-cooled high heat flux armored components for tokamaks. To this was added the complication posed by the need to use a silver-free joining technique that avoids the transmutation of n-irradiated silver to cadmium. The research project involving the four Home Teams (HTs) has focused on the design, development, manufacture and testing of full-scale Plasma Facing Components (PFCs) suitable for ITER. The task addressed all the issues facing ITER divertor design, such as providing adequate armor erosion lifetime, meeting the required armor-heat sink joint lifetime and heat sink fatigue life, sustaining thermal-hydraulic and electromechanical loads, ...
The present article describes the features of the fully-fired combined cycles and the outline of the plant. Hitachi has optimized fully-fired combined cycle systems by executing a heat recovery type combined cycle. For the fully-fired combined cycles, it is possible to raise plant efficiency through the selection of adequate gas turbine types and cycles. It is possible to apply existing boiler facilities, fuel combustion systems, and stacks. It is possible to execute civil and architectural works on existing plants in-service as well as modification works during routine inspections. The NOx increment by gas turbine unit installations can be reduced by denitration plant modifications. Examples of the fully-fired combined cycles under planning are also introduced. Furthermore, the relational technique and operational characteristics are mentioned, as for combustion characteristics under low oxygen concentration in the wind ...
As part of the 1999 NARSTO Northeast Oxidant and Particulate Study (NE-OPS) field campaign, the DOE G-1 aircraft sampled trace gases and aerosols in and around the Philadelphia metropolitan area. Twenty research flights were conducted between July 25 and August 11. The overall goals of these flights were to obtain a mechanistic understanding of O(sub 3) production; to characterize the spatial and temporal behavior of photo-oxidants and aerosols; and to study the evolution of aerosol size distributions, including the process of new particle formation. Within the NE-OPS program, other groups provided additional trace gas, aerosol, and meteorological observations using aircraft, balloon, remote sensing, and surface based instruments (Phillbrick et al., 2000). In this article we provide an overview of the G-1 observations related to O(sub 3) production, focusing on the vertical distribution of pollutants. Ozone production rates are calculated using a ...
A roller bearing hot box sensor utilizing a metallic temperature sensitive elongated wire element. The wire element contacts at temperatures in the range of about 125 F to about 225 F so that when the contraction movement of the wire is attached to a conn...
Previous studies on knowledge of HIV transmission and prevention have used surveys. This study used the question box method to create a safe environment for collecting information on knowledge...Full Text Available
The Dot/Icm-translocated Ankyrin B (AnkB) F-box effector of Legionella pneumophila is essential for intra-vacuolar proliferation and functions as a platform for the docking of polyubiquitinated...Full Text Available
We have previously shown that a T to G transversion at the second T of the conalbumin "TATA" box drastically decreases specific initiation of transcription by RNA polymerase B (1). We now report that...Full Text Available
The oxidation of boron carbide in steam or air was recently extensively studied especially in Forschungszentrum Karlsruhe, Institut fuer Materialforschung. An important data set is available for the interaction modelling. An oxygen diffusion model through the superficial liquid boron oxide formed on the boron carbide external surface associated to a superficial reaction between the liquid boron oxide and steam is proposed to simulate the experimental kinetics from BOX rig and thermogravimetric tests on the interaction between steam and boron carbide at a temperature range 800 C to 1400 C. The oxygen diffusion model will be also useful to simulate interaction between boron carbide and Ar+O2 (air simulation) atmosphere when the steam pressure becomes zero. From the analysis of BOX rig experimental kinetics of non-condensable (H2, CO2, CO and CH4) gases we propose an oxygen diffusion model through the liquid boron oxide and a ...
Thermal fatigue is one of the key factors governing the lifetime of the divertor plate. Tungsten is a promising candidate to cover the surface of the divertor plate in the design of the international thermonuclear experimental reactor (ITER). The W/Cr-bronze divertor small scale mock-ups were manufactured by hot isostatic pressing (HIPing) technique. Thermal fatigue tests of W/Cr-bronze divertor mock-ups have been carried out by an electron beam facility. The mock-ups were tested under a cyclic surface heat flux of 9 MW m"-"2 for 1000 cycles. The electron beam was loaded on the mock-up surface for 20 s and unloaded for 20 s, alternately. The flow rate of water coolant was 0.1 L s"-"1. The 0.3 mm diameter NiCr-NiSi thermocouples were used to monitor the temperature distribution of the mock-up. It was found that the maximum temperature of the tungsten surface was about 400 degree sign C. The saturated ...
Background, aim, and scope Semi-trailers with load boxes are the most important mode of grain transport by land in the world. Load boxes can be produced with different materials such as: wood, steel, and synthetic material. They are responsible for effectiveness retention and quality of grains during the transport. Among the main aspects to be considered and valued when selecting materials for load boxes are the final mass of the semi-trailer, loss of grains, and mechanical properties. Environmental performance is another important aspect to be taken into account for developing and selecting new materials in this kind of application. This study presents a comparative environmental evaluation of load boxes built from two different materials (a wood panel and a three-layer synthetic (TLS) pa...
If gamma-ray bursts originate in galaxies at cosmological distances, the host galaxy should be detected if a burst error box is searched deep enough; are the host galaxies present? We present and implement a statistical methodology which evaluates whether the observed galaxy detections in a burst's error box are consistent with the presence of the host galaxy, or whether all the detections can be attributed to unrelated background galaxies. This methodology requires the model-dependent distribution of host galaxy fluxes. While our methodology was derived for galaxies in burst error boxes, it can be applied to other candidate host objects (e.g., active galaxies) and to other types of error boxes. As examples, we apply this methodology to two published studies of burst error boxes. We find that the nine error boxes observed by Larson and McLean (1997) are too ...
All the recent DEMO design studies for helium cooled divertors utilize tungsten materials and alloys, mainly due to their high temperature strength, good thermal conductivity, low erosion, and comparably low activation under neutron irradiation. The long-term objective of the EFDA fusion materials programme is to develop structural as well as armor materials in combination with the necessary production and fabrication technologies for future divertor concepts. The programmatic roadmap is structured into four engineering research lines which comprise fabrication process development, structural material development, armor material optimization, and irradiation performance testing, which are complemented by a fundamental research programme on "Materials Science and Modeling". This paper prese...
The divertor collector plate in the INTOR reactor will be subjected to high heat, particle, and neutron fluxes, making it the most severely damaged torus component. The collector plate is composed of a protection plate, which is directly exposed to the particle flux, and a heat sink which provides support for the protection plate and carries the water coolant. The high-Z refractory metals have been considered for use as the protection plate material, and austenitic stainless steels and copper alloys have been considered as the heat sink material. Tungsten and Type 316 stainless steels have been selected for the protection plate and heat sink, respectively. The protection plate has a sputtering lifetime of 1.75 y at a 50% duty factor, while the heat sink is expected to last the lifetime of the reactor.
The Doublet III device is operating with an extensive system of plasma limiters and wall protective armor. Operations with up to 8MW of neutral beam power and 1.5MA plasma current are planned. Design and operational performance of the following systems are discussed: 1. Water-cooled graphite moveable limiter. 2. Water-cooled graphite fixed limiter and neutral beam wall armor. 3. Radiatively cooled Inconel divertor plates.
In vibration control field, magneto-rheological (MR) fluid dampers are semi-active control devices that have recently begun to receive more attention. This paper presents a nonlinear black-box model (BBM) and an inverse black-box model (IBBM) for the identification of a MR fluid damper and their application to design a novel force-sensorless control method for any damping system using that damper. The nonlinear model named 'black-box' is a simple direct modeling method which was designed based on fuzzy-neural technique. Characteristics of the damper in study are directly estimated through a fuzzy mapping system. In order to improve the model accuracy, neural network technique including back-propagation and gradient descent method were used to train the fuzzy parameters to minimize the mode...
... No where on an OER or an NCOER is there a box to be checked ... Chaplains will have a issues with it as far as marriage counseling or other issues ...
CAAX proteins are widely involved in global cellular functions such as proliferation, differentiation, and carcinogenesis. As an important modulator of biological activity, signal transduction via protein...Full Text Available
Developing a test standard/protocol for solar box type cookers has drawn a considerable interest among the researchers throughout the world. Recent publications on solar cookers emphasize the need of introducing the thermal performance indicators determined through exergy analysis. In the present paper, the time variation of instantaneous exergy output and energy output as function of its temperature and also of the instantaneous ambient temperature have been reported for truncated pyramid type solar box cooker and compared with those of box type cooker. Further, variations in the exergy lost with temperature difference have been depicted for the selected water temperature range from 60 degreeC to 95 degreeC. Based on this study, quality factor, exergy temperature difference gap product, a...
To understand how DEXD/H-box proteins recognize and interact with their cellular substrates, we have been studying Prp28p, a DEXD/H-box splicing factor required for switching the U1 snRNP with the U6...Full Text Available
Within the framework of the EU power plant conceptual study (PPCS), helium-cooled modular divertor concepts have been investigated in detail at the Forschungszentrum Karlsruhe during the past few years. The first conceptual design proposed was based on convective cooling with the use of flow promoters in the form of pin and/or slot arrays (HEMP/HEMS) to increase the cooling surface and, hence, enhance the heat transfer capacity. While continuing the design optimisation, an advanced multiple-jet design (HEMJ) was introduced, which is based on direct jet-to-wall impinging cooling and offers advantages in terms of simple construction and manufacturing. Main emphasis of the 2004 work program (TW4-TRP-001) lay on experiments for the concepts HEMJ and HEMS, which were mainly performed at the Efremov Institute in St. Petersburg, Russia. For experiment preparation, detailed test programs were worked out and accompanying CFD analyses were accomplished. The outcomes of ...
Austenitic stainless steels (304-type) have been implanted with nitrogen ions in order to investigate the effects of implanted nitrogen on their electrochemical behaviour and on the nature of the passive film formed on the steels in acid (0.5M H{sub 2}SO{sub 4}). Alloys with two nitrogen doses have been prepared (2.5x10{sup 16} and 2x10{sup 17} N atoms/cm{sup 2}). The implanted alloys have been characterized by {sup 15}N-NRA (nuclear reaction analysis) and XPS (X-ray photoelectron spectroscopy). Alloy surfaces with well-defined N concentrations were prepared, prior to the electrochemical measurements, by argon-ion sputtering of the implanted material for a fixed time in order to reach a well-defined point on the nitrogen depth profile. The samples were then transferred without exposure to air to an electrochemical cell mounted in an inert gas glove box. The implanted nitrogen modifies the electrochemical behaviour of the alloy. The anodic ...
Austenitic stainless steels (304-type) have been implanted with nitrogen ions in order to investigate the effects of implanted nitrogen on their electrochemical behaviour and on the nature of the passive film formed on the steels in acid (0.5M H_2SO_4). Alloys with two nitrogen doses have been prepared (2.5x10"1"6 and 2x10"1"7 N atoms/cm"2). The implanted alloys have been characterized by "1"5N-NRA (nuclear reaction analysis) and XPS (X-ray photoelectron spectroscopy). Alloy surfaces with well-defined N concentrations were prepared, prior to the electrochemical measurements, by argon-ion sputtering of the implanted material for a fixed time in order to reach a well-defined point on the nitrogen depth profile. The samples were then transferred without exposure to air to an electrochemical cell mounted in an inert gas glove box. The implanted nitrogen modifies the electrochemical behaviour of the alloy. The anodic dissolution in the active state ...
A balloon-borne instrument has measured the cosmic-ray antiproton flux between 130 and 320 MeV and searched for antihelium between 130 and 370 MeV per nuclear. These particles were selected from the background of normal-matter cosmic rays by combining a selective trigger with a detailed spark chamber visualization of each recorded event. Antiprotons are identified by their characteristic annihilatin radiation. Residue from background processes meeting the selection criteria is small. The observed 14 antiprotons yield a measured differential flux of 1.7 +- 0.5 x 10/sup -4/ antiprotons m/sup -2/ sr/sup -1/ s/sup -1/ MeV/sup -1/ at the top of the atmosphere. The corresponding antiproton/proton ratio is 2.2 +- 0.6 x 10/sup -4/,, only slightly smaller than the ratio observed by other experiments at higher energies. Thus the antiprotons have a spectral shape similar to the protons, at least down to about 100 MeV. The expected flux of these particles can be calculated under the assumption ...
Radiation sterilization has several merits that it is a positively effective sterilization method, it can be used to sterilize low heat-resistant containers and high gas barrier films, and there is no possibility of residual chemicals being left in the packages. It has been commercially used in 'Bag in a Box' and some food containers. The #gamma# ray and an electron beam are commonly used in radiation sterilization. The #gamma# ray can sterilize large size containers and containers with complex shapes or sealed containers due to its strong transmission capability. However, since the equipment tends to be large and expensive, it is generally used in off production lines. On the other hand, it is possible to install and electron beam system on food production lines since the food can be processed in a short time due to its high beam coefficient and its ease of maintenance, even though an electron beam has limited usage such as sterilizing ...
This paper presents the present status of R and D activities on plasma facing components for fusion reactors, such as International Thermonuclear Experimental Reactor (ITER) and fusion demonstration reactor (DEMO). The plasma facing components (PFCs) as typified by divertor and first wall components are subjected to high heat flux and particle flux from fusion plasma. It is essential for these components to have sufficient heat removal capability and robust structure against those loadings. JAEA has been carried out to develop the ITER-PFCs which consist of copper alloys and armor materials with high thermal conductivity, such as carbon fiber composites, tungsten and beryllium. The demonstration of the thermomechanical performance of the ITER-PFCs by using mock-ups has successfully been made under close mutual cooperation between the participant countries of ITER. Currently, the activity on the development of the ITER-PFCs is in a qualification phase prior to the ...
In vibration control field, magneto-rheological (MR) fluid dampers are semi-active control devices that have recently begun to receive more attention. This paper presents a black-box model (BBM) for identification of a MR fluid damper and its application to vibrating control systems using that damper with self-sensing behavior. A model named ''black-box'' is a simple direct modeling method which is designed for a typical MR fluid damper using the self-tuning fuzzy technique. The characteristics of the researched damper are directly estimated through a fuzzy mapping system. In order to improve the accuracy of the proposed model, the back propagation algorithm and gradient descent method were used to train the fuzzy parameters to minimize the model error function. Consequently, the BBM with ...
A study to determine how much energy can be recovered from a Florida citrus processing plant was conducted. The production of ethyl alcohol in particular was examined as it is thought to represent the greatest potential for immediate energy recovery. Three-fourths of the energy expended to produce, harvest, process and market a box of fruit was recoverable using existing technology, i.e. 78,500 Btu/ box of fruit recoverable from a total energy expenditure of 107,800 Btu/ box of fruit. Aside from the actual cost benefits of recovering energy in the form of ethanol, the food processor is also helping to reduce the foreign-oil imports by the blending of ethyl alcohol with unleaded gasoline to form gasohol.
This article aims to open up the biographical black box of three experts working in the boundary zone between science, policy and public debate. A biographical-narrative approach is used to analyse...Full Text Available
Using the Klein-Gordon equation with a box potential, a mass formula describing the family of nonflavored meson states with I = 1 is derived. The energy levels calculated agree with those observed within an accuracy of approx. 5%. In the model discussed quarks behave like tachyons.
A study of two forest areas in India investigated how much energy is wasted when high stumps are left after trees are cut to produce wooden boxes for packing the apple harvest. Measurements of the stumps determined the total wood pulp wasted, which was 1191 tons during 1981. The calorific value of the stumps would supply a year's cooking and heating fuels for 747 families of five. Additional fuel is wasted by abandoning the branches and tree tops which are unsuitable for box construction. 5 references, 4 tables.
Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam ...
New ICRH antennas on JET were designed to couple to the new JET divertor plasma configurations and to improve the Fast Wave Current Drive (FWCD) capabilities. The A2 antenna consists of 4 straps whose currents can be phased at arbitrary angles. The real time automatic tuning acts on frequency, line length (line phase shifters) and stub length. Provision is made for the coupling resistance/plasma position feedback to accommodate the fast changes in antenna loading. The first coupling, tuning and heating results are reported in 0{pi}0{pi}, 0000 and 00{pi}{pi} phasing. A new antenna model is described, which was developed to simulate the measured antenna loading in terms of plasma parameters and to provide a starting point for the real time automatic tuning. 5 refs., 4 figs.
This task within the EU R and D for ITER was aimed at the development of basic manufacturing solutions for the high heat flux plasma facing components such as the divertor targets, the baffles and limiters. More than 50 representative small-scale mock-ups have been manufactured with beryllium, carbon and tungsten armour using various joining technologies. High heat flux testing of 20 of these mock-ups showed the carbon mono-blocks to be the most robust solution, surviving 2000 cycles at absorbed heat fluxes of up to 24 MW m{sup -2}. With flat armour tiles rapid joint failures occurred at 5-16 MW m{sup -2} depending on joining technology and armour material. These test results serve as a basis for the selection of manufacturing options and materials for the prototypes now being ordered. (orig.) 11 refs.
The present invention concerns a high thermal load heat receiving plate such as a divertor plate of a thermonuclear device. The high thermal load heat receiving plate of the present invention has a cooling performance capable of suppressing the temperature of an armour tile to less than a threshold value of the material against high thermal loads applied from plasmas. Spiral polygonal pipes are inserted in cooling pipes at a portion receiving high thermal loads in the high temperature load heat receiving plate of the present invention. Both ends of the polygonal pipes are sealed by lids. An area of the flow channel in the cooling pipes is thus reduced. Heat conductivity on the cooling surface of the cooling pipes is increased in the high thermal load heat receiving plate having such a structure. Accordingly, temperature elevation of the armour tile can be suppressed. (I.S.).
Until the concerns about indoor air quality (IAQ) reached a peak in the last five years, interior zones of office buildings were traditionally served with cooling-only shut-off variable air volume (VAV) boxes. Heat gains from lighting and equipment, in addition to those from occupants themselves, caused supply air quantities of 13 C to 15 C (55 F to 60 F) air to be sustained at rates on the order of 2.5 L/s per square meter (0.5 cfm per square feet), a rate that most designers at the time felt would provide a comfortable and well ventilated environment. More recently, the reduction in lighting loads, the use of cold air systems, and, most importantly, the concern that acceptable indoor air quality may not be maintained at low air flow rates, has led to a different solution in interior zones: the series fan-powered mixing box.
We hypothesized that I kappa B kinase (IKK)-mediated nuclear factor kappa B and forkhead BoxO3a phosphorylation will be associated with age-related endothelial dysfunction. Endothelium-dependent dilation and aortic protein expression/phosphorylation were determined in young and old male B6D2F1 mice and old mice treated with the IKK inhibitor, salicylate. IKK activation was greater in old mice and was associated with greater nitrotyrosine and cytokines. Endothelium-dependent dilation, nitric oxide (NO), and endothelial NO synthase phosphorylation were lower in old mice. Endothelium-dependent dilation and NO bioavailability were restored by a superoxide dismutase mimetic. Nuclear factor kappa B and forkhead BoxO3a phosphorylation were greater in old and were associated with increased express...
Theoretical investigations on the phase change materials (PCMs) used as the heat storage media for box-type solar cookers have been conducted in this study. The selected PCMs are magnesium nitrate hexahydrate, stearic acid, acetamide, acetanilide and erythritol. For a two-dimensional simulation model based on the enthalpy approach, calculations have been made for the melt fraction with conduction only. Different materials such as glass, stainless steel, tin, aluminum mixed, aluminum and copper are used as the heat exchanger container materials in the numerical calculations. The large value of thermal conductivity of heat exchanger container material did not make a significant contribution on the melt fraction except for at very low thermal conductivities. Based on the theoretical results, stearic acid and acetamide are found to be good compatibility with latent heat storage system. It is also found that the initial temperature of PCM does not have very important ...
As compared with terrestrial circuits, the communication satellite possesses superior characteristics such as wide area coverage, broadcasting, high capacity, and robustness to disasters. Utilizing the narrow band channel (64 kbps) of the geostationary satellite JCSAT 1 located at the altitude of 36,000 km above the equator, the authors investigated satellite-relayed medical imagings by video signals, with bone scintigraphy as a model. Each bone scintigraphy was taken by a handy-video camera, digitalized and transmitted from faculty of technology located at 25 kilometers apart from our department. Clear bone scintigraphy was obtained via satellite, as seen on the view box. Eight nuclear physicians evaluated 20 cases of bone scintigraphy. ROC (Receiver Operating Characteristic) analysis was performed between the scintigraphies on view box and via satellite by the rating method. The area under the ROC curve was 91.6#+-#2.6% via satellite, and ...
A cryocondensation pump was designed for the baffle chamber of General Atomics DIII-D tokamak and will be installed in the fall of 1992. The purpose of the pump is to study plasma density control by pumping the divertor. The pump is toroidally continuous, approximately 10 m long and located in the lower outer corner of the vacuum chamber of the machine. It consists of a 1 m{sup 2} liquid helium-cooled surface surrounded by a liquid nitrogen-cooled shield to limit the heat load on the helium-cooled surface. The liquid nitrogen-cooled surface is surrounded by a radiation/particle shield to prevent energetic particles from impacting and releasing condensed water molecules. A thermal enhancement coating was applied to the nitrogen shell to lower the maximum temperature of the shell. The coating is non-continuous to keep the toroidal electrical resistance high. The whole pump is supported off the water-cooled vacuum vessel wall. Supports for the pump were designed to ...
We study the consumption-portfolio problem in a setting with capital gain taxes and multiple risky stocks to understand how short selling influences portfolio choice with a shorting-the-box restriction. Our analysis uncovers a novel trading flexibility strategy whereby, to minimize future tax-induced trading costs, the investor optimally shorts one of the stocks (or equivalently, buys put options) even when no stock has an embedded gain. Alternatively, an imperfect form of shorting the box can reduce aggregate equity exposure ex post. Given these two short selling strategies, it is common for an unconstrained investor to short some equity while a constrained investor holds a positive investment in all stocks. With no shorting, the benefit of trading separately in multiple stocks is not eco...
Objective: Atherosclerosis is an inflammatory disease, modulated by plaque stabilizing and de-stabilizing cell populations such as infiltrating monocytes and vascular smooth muscle cells (vSMCs). Transcription factors regulating proliferation and differentiation of atherosclerosis relevant cell types are of interest in this context. The forkhead box transcription factor FoxP1 modulates monocyte differentiation. We studied FoxP1 expression in atherosclerotic tissue, correlated FoxP1 expression with plaque characteristics and identified associations between FoxP1 and plaque proteins. Methods: 116 Atherosclerotic plaques from carotid endarterectomy samples were histologically classified (fibrous, fibroatheromatous, atheromatous) and subjected to semi-quantitative protein analysis. Macrophage,...
The objectives of the project were to make significant improvements in the production of stall regulated blades in the areas of (a) the tip box, its housing, its mechanism and small GRP parts; (b) mould technology; (c) resins and glues and (d) root tooling. Although wood composite had been identified as a competitive technology for blades, compared with GRP blades, production volumes had been lower; reasons are given. The way in which the four areas identified for investigation were tackled are discussed. The study showed that the mould cycle time can be reduced to two days for a stall regulated blade and the blade quality can be improved by using the composite tip box and new resins. The time required for replication of moulds can be reduced by 40%.
Stimulated bremsstrahlung in an undulating electric field in the lasing beam direction (electric wiggler) was shown to be possible from the quantum- mechanical viewpoint. Herein, this possibility is scrutinized from the viewpoint of classical electrodynamics. It is found that if stimulated bremsstrahlung in a transverse undulating magnetic field (magnetic wiggler) occurs, stimulated bremsstrahlung in the electric wiggler must also occur. We further show that a free electron laser (FEL) using a magnetic wiggler to provide a catalyzer field for stimulated bremsstrahlung cannot serve as a practical FEL operating in the soft x-ray region from both theoretical and experimental viewpoints. On the other hand, the authors demonstrate that the FEL using a traveling wake field in a two-beam elliptical pill-box cavity is well suited as a source of coherent radiation in the soft x-ray region.
mRNP granules at adult central synapses are postulated to regulate local mRNA translation and synapse plasticity. However, they are very poorly characterized in vivo. Here, in Drosophila...Full Text Available
The subject of parallelism (or concurrency) has seen little light outside books and courses on operating systems. The authors feel that this is too restricted an arena and that the subject should be dealt with in a wider context. With the aim of trying to rectify the situation they have used, several times, as a teaching aid the study of the use of a computer to control a juke box. The article describes how they use this case study. 2 references.
protect digital information, from personal details held on a computer to financial details transmitted over the Internet. Encryption ...in connection with electronic data (Box 2), whether stored on a computer or transmitted over an unsecured network such as ...Encryption tools (usually in the form of computer programs or software) are widely available
The solar array wings were deployed by swinging two half-blanket boxes open from a folded hinge launch position .... pure-water by-product of the shuttle's fuel cell power generators because ..... outgassing limits, flammability limits, ... Foale fills a water microbiology bag for in-flight analysis. ...
A total of 172 persons from nine South Amerindian, three African and one Eskimo populations were studied in relation to the Paired box gene 9 (PAX9) exon 3 (138 base...Full Text Available
This paper presents the results obtained in the gamma scanning of two fuel pins from the bent subassembly of the fast breeder test reactor (FBTR) using a segmented gamma scanning system employing segment correlation developed for the assay of glove box solid waste. In addition to the actinide profiles, the paper also discusses the fission products and clad activation product profiles and tries to correlate the experimental values of the latter with computed values. (author). 4 refs., 1 fig., 1 tab.
The expression status of the estrogen receptor alpha (ERα) and that of the epidermal growth factor receptor Her-2/neu frequently correlate inversely in breast cancers. While ERα-dependent...Full Text Available
In conveyor type irradiators, the movement of conveyor and the product boxes is not there until the source is fully in the irradiation position. In case the conveyor system fails the source must automatically be returned to its shielded storage vault. The dose received by the product during the movement of the source from or to the shield becomes significant if the total dose to be received by the product is small. A study has been carried out for evaluating the transient dose received by onions in the POTON irradiator. The results of the study are discussed in this paper. (author)
...Box Contains One Month Supply Dietary supplement with a premium patented formula of L-Arginine, Ginseng, Ginkgo plus 13 essential vitamins, antioxidants, and minerals to support male sexual function . ArginMax for Male Sexual Fitness is a patented combination of l-Arginine, Ginseng, Ginkgo, and 13 essential vitamins and ...
Studies of flower development in core eudicot species have established a central role for B class MADS-box genes in specifying petal and stamen identities. Similarly in maize and rice, B class genes...Full Text Available
AbstractT-box family transcription factors play many roles in Metazoan development. Here we characterise Tbx6r, a unique Tbx6 paralogue isolated from the amphibian Xenopus....Full Text Available
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on current design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under asymmetrically heated conditions. ...
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under ...
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under ...
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under ...
The use of deuterium-tritium fuel in the Compact Ignition Tokamak will require applying remote handling technology for ex-vessel maintenance and replacement of machine components. Highly activated and contaminated components of the fusion devices auxiliary systems, such as diagnostics and RF heating, must be replaced using remotely operated maintenance equipment in the test cell. In-vessel remote maintenance included replacement of divertor and first wall hardware, faraday shields, and for an in-vessel inspection system. Provision for remote replacement of a vacuum vessel sector, toroidal field coil or poloidal field ring coil was not included in the project baseline. As a result of recent coil failures experienced at a number of facilities, the CIT project decided to reconsider the question of remote recovery from a coil failure and, in January of 1990, initiated a coil replacement study. This study focused on the technical requirements and impact on fusion ...
The economic prospects for magnetic fusion energy can be dramatically improved if for the same total power output the fusion neutron first-wall (FW) loading and the system power density can be increased by factors of 3 to 5 and 10 to 30, respectively. A number of compact fusion reactor embodiments have been proposed, all of which would operate with increased FW loadings, would use thin (0.5 to 0.6 m) blankets, and would confine quasi-steady-state plasma with resistive, water-cooled copper or aluminum coils. Increased system power density (5 to 15 MWt/m/sup 3/ versus 0.3 to 0.5 MW/m/sup 3/), considerably reduced physical size of the fusion power core (FPC), and appreciably reduced economic leverage exerted by the FPC and associated physics result. The unique materials requirements anticipated for these compact reactors are outlined against the well documented backdrop provided by similar needs for the mainline approaches. Surprisingly, no single materials need that is unique to the ...
Particulate (i.e. tokamak dust) has been collected from the DIII-D tokamak located at General Atomics in San Diego, CA, USA. Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Sampling was completed in four toroidal locations of the machine; the 0-90 area, the 90-180 area, the 180-270 area, and the 270-360 area. The 0 direction designates the north side of the DIII-D machine. Four tiles in each area were sampled; the first vertical tile above the floor on the centerpost, a floor tile next to the center post, a tile on the isolated ring, and the first tile up from the isolated ring on the divertor. In addition, samples were collected from underneath the floor tiles at the 275 and the 75 locations. The count median diameter of the ...
The invention relates to a method for purifying a gas mixture containing at least one undesirable gas compound utilizing certain sulfonamide or sulfamide solvents.
In this paper, we study data structures for use in N-body simulation. We concentrate on the spatial decomposition tree used in particle-cluster force evaluation algorithms such as the Barnes-Hut algorithm. We prove that a k-d tree is asymptotically inferior to a spatially balanced tree. We show that the worst case complexity of the force evaluation algorithm using a k-d tree is {Theta}(n log{sup 3} n log L) compared with {Theta}(n log L) for an oct-tree. (L is the separation ratio of the set of points.) We also investigate improving the constant factor of the algorithm, and present several methods which improve over the standard oct-tree decomposition. Finally, we consider whether or not the bounding box of a point set should be {open_quotes}tight{close_quotes}, and show that it is only safe to use tight bounding boxes for binary decompositions. The results are all directly applicable to practical implementations of N-body algorithms.
The microbial process of converting organic matter into methane and carbon dioxide is so complex that anaerobic digesters have long been treated as {open_quotes}black boxes.{close_quotes} Research into this process during the past few decades has gradually unraveled this complexity, but many questions remain. The major biochemical reactions for forming methane by methanogens are largely understood, and evolutionary studies indicate that these microbes are as different from bacteria as they are from plants and animals. In anaerobic digesters, methanogens are at the terminus of a metabolic web, in which the reactions of myriads of other microbes produce a very limited range of compounds - mainly acetate, hydrogen, and formate - on which the methanogens grow and from which they form methane. {open_quotes}Interspecies hydrogen-transfer{close_quotes} and {open_quotes}interspecies formate-transfer{close_quotes} are major mechanisms by which methanogens obtain their ...
Development of the engineering technology basis of pyrometallurgical reprocessing is a key issue for industrialization. For development of the transport technologies of molten salt and liquid cadmium at around 500 deg. C, a salt transport test rig and a metal transport test rig were installed in Ar glove box. Function of centrifugal pump and 1/2'' declined tubing were confirmed with LiCl- KCl molten salt. The transport behavior of molten salt was found to follow that of water. Function of centrifugal pump, vacuum sucking and 1/2'' declined tubing were confirmed with liquid Cd. With employing the transport technologies, industrialization applicable electro-refiner was newly designed and engineering-scale model was fabricated in Ar glove box. The electro-refiner has semi-continuous liquid Cd cathode instead of conventional one used in small-scale tests. With using actinide-simulating elements, demonstration of industrial-scale throughput will be ...
The Tevatron accelerator at Fermilab incorporates long two-phase helium passages. During magnet design, the generalized flow map of Baker was used to predict homogeneous flow. Longer than expected magnet time constants led to this investigation. The importance of predicting the flow regime has been amplified with the advent of non-horizontal accelerator designs. A test setup was constructed at Fermilab to investigate two-phase helium flow regimes for conditions practical in accelerator designs. The setup consisted of a standard Tevatron satellite refrigerator, subcooling dewar, heater, 35 m long transfer line, and a specialized end box. A knife blade on the midplane of the transfer line diverted the flow from the upper and lower halves of the pipe to separate vessels in the end box. The amount of liquid above and below the plane was measured at various total mass flow rates and liquid percentages. The results show that stratified flow occurs at ...
The objective of this study is to comprehend the basic structural characteristics of box shaped mixed structures proposed for a future nuclear reactor building structure. Specimens of reinforced concrete precast panel walls of the mixed structures were prepared using ultrahigh strength materials. Two bending shear tests were conducted with a parameter of the quantity of reinforcement bars. The results include: (1) Relationship of shear stress and the angle of the structure, and (2) Failure mode. (author)
We propose to encode a register of quantum bits in different collective electron spin wave excitations in a solid medium. Coupling to spins is enabled by locating them in the vicinity of a superconducting transmission line cavity, and making use of their strong collective coupling to the quantized radiation field. The transformation between different spin waves is achieved by applying gradient magnetic fields across the sample, while a Cooper pair box, resonant with the cavity field, may be used to carry out one- and two-qubit gate operations.
This document is a progress report to the USDOE Atmospheric Radiation and Measurement Program (ARM). The overall project goal is to relate subgrid-cumulus-cloud formation, coverage, and population characteristics to statistical properties of surface-layer air, which in turn are modulated by heterogeneous land-usage within GCM-grid-box-size regions. The motivation is to improve the understanding and prediction of climate change by more accurately describing radiative and cloud processes.
The potential strategic impact of regime change in Iraq and Iran on OPEC in the long-run is explored. In the first part of the paper short overviews are given of the present international oil market; of US oil import issues and energy policy; of the strategic position of the US in the Persian Gulf and of geopolitical developments in the Persian Gulf at large. Also, attention is paid to the OPEC and the role of a 'new' Iraq. In the second part the game of 'boxed pigs' is used to explore the possible strategic impact of regime change in Iraq and possible regime change in Iran on OPEC. This exploration takes place within four possible futures for the Gulf.
We construct the quantum mechanical field operator of the two-dimensional Liouville theory in a finite box. This leads us to the discovery of a new type of triangle relation which does not reduce to the already known ones. We apply our result to the construction of the string model in an arbitrary number of space-time dimensions D. We show that there are no tachyons in -infinite1, which is a strong-coupling region for the Liouville field theory. (orig.).
A manipulator for checking the inside of a vertical, flange-shaped collector of a horizontal steam generator consists of a rotating mast with bearings at the top and bottom ends with a support that can be moved along the length of the mast for the checking system mountings. The support is propelled by a drive spindle placed parallel to the mast with its drive head bearing in the support and locked into a toothed rack attached to the mast. The checking system mountings are fitted in or on the walls of the support and are very close to the box-shaped support. Their retractable arms are hinged.
We give a general local central limit theorem for the sum of two independent random variables, one of which satisfies a central limit theorem while the other satisfies a local central limit theorem with the same order variance. We apply this result to various quantities arising in stochastic geometry, including: size of the largest component for percolation on a box; number of components, number of edges, or number of isolated points, for random geometric graphs; covered volume for germ-grain coverage models; number of accepted points for finite-input random sequential adsorption; sum of nearest-neighbour distances for a random sample from a continuous multidimensional distribution.
A study for Cs-137 radionuclide dispersion in the marine environment through of compartmental model (Box Model) is presented. The model simulates the surface water contamination caused by direct atmospheric deposition, surface wash off, desorption from sediments and transfer with the ground water of accidentally released radionuclides. For this study the model was applied to the North Sea, near to Sellafield, based on the transfer coefficients obtain at the literature. The results obtained are in good agreement with the literature, being that the model developed can be applied in to the brazilian coastal regions. (author). 7 refs, 7 figs.
Human BTEB cDNA clones have been isolated, sequenced, and the corresponding gene has been assigned to human chromosome 9, region q13, by fluorescent in situ hybridization and DNA blot analysis using DNAs from hybrid cell clones containing a single human chromosome. The cDNA clone encodes a polypeptide of 244 amino acids whose sequence shows a high sequence similarity with the rat BTEB (98% amino acid identity).
A method for automatic optimal feeder design in steel casting processes is presented. The initial design is the casting part (without feeders) which is placed in a suitable mold box. Design of each feeder contains the following steps: determination of the feeder-neck connection point on the casting surface, initial feeder design, feeder shape optimization and feeder topology optimization. Completing designing the first feeder, the method attends to designing the next one, if it is required, and the same procedure will be repeated. In the presented method, feeders are designed in a descending order of their sizes. The feasibility of the presented method is supported with an illustrative example.
While underground power transmission lines have become to use CV cables as the mainstream, existing facilities still use OF cables. Factors of OF cable deterioration include heat cycles during operation and surge intrusion. As a method to diagnose this deterioration in insulation, characteristics tests are performed by collecting insulation oil in a cable connection box. The insulation oil collection work has been done conventionally with the power line stopped to prevent danger from induction voltage. A power uninterruptible oil collection tool was developed recently. The tool consists mainly of an insulator made of epoxy resin, wherein a connection box connector is rotated and loosened by operating an insulating operation rod, with the structure not contacted directly with metallic sheath, so that insulation oil can go through the oil collecting tool and gets collected. Discussions were given on the tool to be capable of collecting samples ...
A publication on Norwegian gas and gas export. The content is wide spread from use of gas in daily life via sub sea pipeline repair systems to an overview over tomorrows gas fields. (AG)
A gas diffusion semiconductor electrode and solar cell and a process for gaseous fixation, such as nitrogen photoreduction, CO/sub 2/ photoreduction and fuel gas photo-oxidation are described. The gas diffusion photosensitive electrode has a central electrolyte porous matrix with an activated semiconductor material on one side adapted to be in contact with an electrolyte and a hydrophobic gas diffusion region on the opposite side adapted to be in contact with a supply of molecular gas.
The book tries about the International and national aspects, natural gas situation, production, consumption, prices, demand projection, energetic plans, norms and laws of the natural gas in Colombia
This document provides information on the supply and disposition of natural gas to a wide audience. The 1996 data are presented in a sequence that follows natural gas from it`s production to it`s end use.
The origin of natural gas in the Japanese oil and gas fields are geochemically studied. Samples are taken from structural natural gas, surface gas seepage, water-dissolved natural gas and coal-field gas of the Japan Sea coast area. The origins of primary hydrocarbons are classified into bacteria gas and thermogenic gas, the latter being subclassified into gas in oil production zone with the per million deviation of the carbon isotope (/sup 13/C/sup 1/) of methane less than -35 and those gases with maturity higher than this. Surface gas seepage is subjected to migration and bacterial oxidation. Coal gas is similar to oil gas. The CO/sub 2/ concentration is 0 - 2% and /sup 13/CO/sub 2/ deviations from -30 - +30. The origin can be barely ...
Many older homes are equipped with mercury-containing gas regulators that reduce the pressure of natural gas in the mains to the low pressure used in home gas piping. Removal of these regulators can...Full Text Available
Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of two-phase flow regimes and regime transitions of boiling water in horizontal rectangular ...
Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of two-phase flow regimes and regime transitions of boiling water in horizontal rectangular ...
Sewage gas or biogas as a product of anaerobic digestion contains methane and carbon dioxide as its main components. Biogas is scrubbed off carbon dioxide in absorption columns and purified to natural-gas quality. The purified gas then is piped to the gas pressure control station and fed into the public network. Description of process and plant is given.
Several shield options were analyzed for the ITER conceptual design to minimize the nuclear responses in the toroidal field (TF) coils. The total nuclear heating in the physics phase and the insulator dose in the technology phase are the most critical parameters in the design process. The first shield option has type 316 stainless steel and water shielding material. Steel and water also serve as structural material and coolant, respectively. The second option is similar to the first except that borated water is used instead of ordinary water. The other two options include a small layer of lead or boron carbide (B{sub 4}C) at the back of the shield. The last three shield options were considered to reduce the nuclear heating in the toroidal field coils relative to the steel/water shield. An optimization process was performed taking into consideration the thermal-hydraulics and the engineering requirements to define the shield configuration. A careful integration was performed to ...
Activation dose rates have been computed for the Poloidal Divertor Experiment Tokamak at the Princeton Plasma Physics Laboratory. Dose rates were computed in one-dimensional (cylindrical) geometry using the ANISN S/sub n/ transport theory code and the DKR radioactivity code. The EPR (DLC37F) 121-group coupled neutron-gamma cross section library was used with ANISN. For DKR, the 46-group neutron library of DCDLIB was employed. Dose rates were calculated for 1 minute, 1 hour, 6 hours, 24 hours, 1 week, and 1 month following a single pulse yielding 10/sup 15/ neutrons and for 2 hypothetical pulsing sequences. First, it was assumed that 10 pulses were conducted each day (1 hour apart) for 5 days. Second, it was assumed that 100 pulses were conducted each day (6 minutes apart) for 5 days. It was found that /sup 56/Mn and /sup 64/Cu are the main contributors to the dose at short time periods after shutdown, while, for long time periods, /sup 58/Co and /sup 51/Cr ...
This article presents a hands-on web-based activity motivated by the relation between human health and ozone pollution in California. This case study is based on multivariate data collected monthly at 20 locations in California between 1980 and 2006. Several strategies and tools for data interrogation and exploratory data analysis, model fitting and statistical inference on these data are presented. All components of this case study (data, tools, activity) are freely available online at: http://wiki.stat.ucla.edu/socr/index.php/SOCR_MotionCharts_CAOzoneData. Several types of exploratory (motion charts, box-and-whisker plots, spider charts) and quantitative (inference, regression, analysis of variance (ANOVA)) data analyses tools are demonstrated. Two specific human health related questions...
At moderately low momentum transfer ($-t$ up to 1 GeV$^2$) the coupling to the vector meson production channels gives the dominant contribution to real Compton and deeply virtual Compton scattering (DVCS). Starting from a Regge Pole approach that successfully describes vector meson production, the singular part of the corresponding box diagrams (where the intermediate vector meson-baryon pair propagates on-shell) is evaluated without any further assumptions (unitarity). Such a treatment explains not only the unexpectedly large DVCS unpolarized cross section that has been recently measured at Jefferson Laboratory (JLab), but also all the beam spin and charge asymmetries that has been measured at JLab and Hermes, without explicit need of Generalized Parton Distributions (GPD). The issue of the relationship between the two approaches is addressed.
By means of an analogous simulator, which can simulate a power supply system, a method to determine the transfer function of a Power System Stabilizer (PSS) is developed. The purpose of the PSS is to damp unwanted electro-mechanical oscillations. The method is very systematic and there is no need for specified values of the parameters used in the system. It is assumed that the power generator system is linear for small variations. The system can be considered to be a black box. Measurements executed by means of this method are completely controlled by the person who enforces the measurement. By applying this method carefully, irregularities are almost out of the question. The equipment necessary are a PC with two AD-ports and an adjustable sinus-generator. A comparison is made with a more traditional method, in which a spectrum analyzer is used. 4 figs., 7 refs.
The Working Group reviewed the revised Who guidance and the information published since 1991 on the risks of thyroid cancer in children from radioiodine and the risks of side effects from stable iodine. In particular, it reviewed data compiled on the incidence of thyroid cancers in children following the accident at the Chernobyl nuclear power plant in 1986. It considered whether the NRPB Earls were still appropriate, in the light of the new data. It also reviewed a range of other recommendations given by the 1st Working Group, concerning the chemical form of stable iodine tablets and practical issues concerning implementation of stable iodine prophylaxis. Finally, it reviewed the Patient Information Leaflet that is required, by law, to be included in each box of tablets and provided suggestions for information to be included in a separate information leaflet to be handed out to the public when stable iodine tablets are distributed
The recent developments in the mobile technology (mobile phones, middleware) created a need for new methods of protecting the code transmitted through the network. The proposed mechanisms not only secure the compiled program, but also the data, that can be gathered during its "journey". The oldest and the simplest methods are more concentrated on integrity of the code itself and on the detection of unauthorized manipulation. Other, more advanced proposals protect not only the code but also the execution state and the collected data. The paper is divided into two parts. The first one is mostly devoted to different methods of securing the code and protecting its integrity; starting from watermarking and fingerprinting, up to methods designed specially for mobile agent systems: encrypted function, cryptographic traces, time limited black-box security, chained-MAC protocol, publicly-verifiable chained digital signatures The second part presents new concept for ...
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Radon concentration in the bed rooms, kitchens, sitting rooms and TV lounges in some houses in the Lahore has been measured using CN-85 Solid State Nuclear Track Detectors in box type dosimeters. Maximum value of radon concentration is 93 Bq/m/sup 3/ in a bed room whereas the minimum value is 25 Bq/m/ sup 3/ in a TV lounge. The average value of radon concentration in bed rooms, kitchens, sitting rooms and TV lounges varies between 43 Bq/m/sup 3/ and 55 Bq/m/sup 3/. Comparison of radon concentration in the old and new houses has been done and no specific relationship has been observed. (author).
Pre-amorphization of ultrashallow implanted boron in Silicon-on-insulator is optimized to produce an abrupt box-like doping profile with negligible electrical deactivation and significantly reduced transient enhanced diffusion. The effect is achieved by positioning the as-implanted amorphous/crystalline interface close to the buried oxide interface, to minimize interstitials whilst leaving a single-crystal seed to support solid-phase epitaxy. Based on a simple physical model of our results, we estimate that the interface between the Si overlayer and the buried oxide is an efficient interstitial sink with a recombination length of the order of 10nm or less under our experimental conditions. (author)
Forster et al. recently showed that weak nonlocality can be amplified by giving the first protocol that distills a class of nonlocal boxes (NLBs) [Phys. Rev. Lett. 102, 120401 (2009)] We first show that their protocol is optimal among all nonadaptive protocols. We next consider adaptive protocols. We show that the depth-2 protocol of Allcock et al. [Phys. Rev. A 80, 062107 (2009)] performs better than previously known adaptive depth-2 protocols for all symmetric NLBs. We present a depth-3 protocol that extends the known region of distillable NLBs. We give examples of NLBs for which each of the Forster et al., the Allcock et al., and our protocols perform best. The understanding we develop is that there is no single optimal protocol for NLB distillation. The choice of which protocol to use depends on the noise parameters for the NLB.
A detailed discussion of airborne CO{sub 2}, DIAL measurements obtained from the first joint N-ABLE field campaign at INEL is presented. System performance characteristics, including return signal strength, averaging statistics, and temporal correlation as well as multi-line DIAL spectral data are discussed. In particular, we review data acquisition and analysis strategies pertinent to chemical detection from a moving platform, such as range determination and correction, and return signal processing (waveform vs. box-car integration, baseline correction). We also report observed effects and variations due to near-field light scattering, pointing and tracking stability, and stack-release plume dynamics.
Genetic mapping is approached using the techniques of high resolution fluorescence in situ hybridization (FISH). This technology and the results of its application are designed to rapidly generate whole genome as tool box of expressed sequence to speed the identification of human disease genes. The results of this study are intended to dovetail with and to link the results of existing technologies for creating backbone YAC and genetic maps. In the first eight months, this approach generated 60--80% of the expressed sequence map, the remainder expected to be derived through more long-term, labor-intensive, regional chromosomal gene searches or sequencing. The laboratory has made significant progress in the set-up phase, in mapping fetal and adult brain and other cDNAs, in testing a model system for directly linking genetic and physical maps using FISH with small fragments, in setting up a database, and in establishing the validity and throughput of the system.
The formation of a through-gut was a key innovation in the evolution of metazoans. There is still controversy regarding the origin of the anus and how it may have been either gained or lost during evolution in different bilaterian taxa. Thus, the study of groups with a blind gut is of great importance for understanding the evolution of this organ system. Here, we describe the morphogenesis and molecular patterning of the blind gut in the sexual triclad Schmidtea polychroa. We identify and analyze the expression of goosecoid, commonly associated with the foregut, and the GATA, ParaHox and T-box genes, members of which commonly are associated with gut regionalization. We show that GATA456a is expressed in the blind gut of triclads, while GATA456b is localized in dorsal parenchymal cells. Goo...
The superconducting magnets and associated cryogenic components in A-sector represent the initial phase of installation of the Fermilab superconducting accelerator, designed to accelerate proton beams to energies of 1 TeV. Installation of the magnets, comprising one-eighth of the ring, was completed in December, 1981. Cooldown and power tests took place in the first half of 1982, concurrent with main ring use for 400 GeV high energy physics. The tests described in this paper involved 151 cryogenic components in the tunnel: 94 dipoles, 24 quadrupoles, 25 spool pieces, 3 feed cans, 4 turn-around boxes and 1 bypass. Refrigeration was supplied by three satellite refrigerators, the Central Helium Liquefier, and two compressor buildings. The magnets were powered by a single power supply.
A UPS based on a line-interactive system for CATV (Cable TV) networks has been newly developed. An inverter of the UPS featuring a pure sine wave output and equipped with an uninterrupptible transfer switch made it possible to raise its reliability high and to reduce the uninterruptible transfer time from 50 {approx} 100 ms to only 3 ms. The expected life of 15 years and maintenance-free of the UPS were realized by monitoring and optimizing the operational conditions of lead-acid batteries, aluminum electrolytic capacitors and cooling fans. The use of rust- and weather- resistant painting methods for an outer box of the UPS also contributed to extend the life of the system. (author)
Development of the engineering technology basis of pyrometallurgical reprocessing is a key issue for industrialization. For development of the transport technologies of molten salt and liquid cadmium at around 773 K, a salt transport test rig and a metal transport test rig were newly installed in an Ar glove box. Function of the salt transport test rig was confirmed with LiCl-KCl molten salt, and the transport behaviour of molten salt was found to follow that of water. The molten salt/liquid metal contactor for Ln/An separation was newly designed and installed. The test with a single-stage contactor was successful with simulated elements, and a three-stage contactor is now under development. A large-scale electro-refiner with a function to transport molten salt and liquid cadmium were newly designed, and to be installed for demonstration test with simulated materials. (authors)
Direct Flame Impingement involves the use of an array of very high-velocity flame jets impinging on a work piece to rapidly heat the work piece. The predominant mode of heat transfer is convection. Because of the locally high rate of heat transfer at the surface of the work piece, the refractory walls and exhaust gases of a DFI furnace are significantly cooler than in conventional radiant heating furnaces, resulting in high thermal efficiency and low NOx emissions. A DFI furnace is composed of a successive arrangement of heating modules through or by which the work piece is conveyed, and can be configured for square, round, flat, and curved metal shapes (e.g., billets, tubes, flat bars, and coiled bars) in single- or multi-stranded applications.
Unitarity cuts are widely used in analytic computation of loop amplitudes in gauge theories such as QCD. We expand upon the technique introduced in hep-ph/0503132 to carry out any finite unitarity cut integral. This technique naturally separates the contributions of bubble, triangle and box integrals in one-loop amplitudes and is not constrained to any particular helicity configurations. Loop momentum integration is reduced to a sequence of algebraic operations. We discuss the extraction of the residues at higher-order poles. Additionally, we offer concise algebraic formulas for expressing coefficients of three-mass triangle integrals. As an application, we compute all remaining coefficients of bubble and triangle integrals for nonsupersymmetric six-gluon amplitudes.
Chapter one is a review of the relevant literature. In chapter two the coordination chemistry of biphenyl-tailed terpyridines with octahedral metal dications is investigated. The effect of different metal ions on their aggregation modes in the solid state is also investigated. In chapter three the coordination chemistry of polyaryl-tailed terpyridines with octahedral metal dications is investigated. The effect of different aryl tails on their aggregation modes in the solid state is investigated. In chapter four the pi-pi aggregation of molecular boxes through biphenyl tails is studied. In chapter five the immobilisation of aryl tailed complexes into polyelectrolyte films has been investigated, and the arrangement of these complexes in the films has been compared with same complexes in the crystal, thus moving from three dimensional aggregation to two dimensions.
The central engine of Gamma Ray Bursts is hidden from direct probing with photons mainly due to the high densities involved. Inferences on their properties are thus made from their cosmological setting, energetics, low-energy counterparts and variability. If GRBs are powered by hypercritical accretion onto compact objects, on small spatial scales the flow will exhibit fluctuations, which could in principle be reflected in the power output of the central engine and ultimately in the high energy prompt emission. Here we address this issue by characterizing the variability in neutrino cooled accretion flows through local shearing box simulations with magnetic fields, and then convolving them on a global scale with large scale dynamical simulations of accretion disks. The resulting signature is characteristic, and sensitive to the details of the cooling mechanism, providing in principle a discriminant for GRB central engine properties.
Potential of spent biomass of a cyanobacterium, Nostoc linckia HA 46, from a hydrogen bioreactor was studied for biosorption of a textile dye, reactive red 198. The waste biomass was immobilized in calcium alginate and used for biosorption of the dye from aqueous solution using response surface methodology (RSM). Kinetics of the dye in aqueous solution was studied in batch mode. Interactive effects of initial dye concentration (100-500mg/L), pH (2-6) and temperature (25-45^oC) on dye removal were examined using Box-Behnken design. Maximum adsorption capacity of the immobilized biomass was 93.5mg/g at pH 2.0, initial concentration of 100mg/L and 35^oC temperature, when 94% of the dye was removed. Fourier transform infrared (FT-IR) studies revealed that biosorption was mainly mediated by fun...
A rapid combustion unit (Baird and Tatlock) incorporating a combustion chamber provided with baffle plates for complete combustion of the sample without the use of a catalyst has been assembled in a glove box for the determination of carbon and hydrogen in actinide complexes. The unit has been modified employing a movable electric furnace and a proportional temperature controller, for decomposition of the sample at desired heating rates. The set-up was standardised employing various reference materials such as benzoic acid, acetanilide, sulphanilamide and 1-chloro 2:4 dinitrobenzene and the standard deviation in the measurements evaluated. It has also been used successfully for the determination of carbon in uranium carbide and carbon and hydrogen in some uranyl-#beta#-diketone-amine N-oxide complexes and in plutonium(IV) oxalate. (auth.).
A rapid combustion unit (Baird and Tatlock) incorporating a combustion chamber provided with baffle plates for complete combustion of the sample without the use of a catalyst has been assembled in a glove box for the determination of carbon and hydrogen in actinide complexes. The unit has been modified employing a movable electric furnace and a proportional temperature controller, for decomposition of the sample at desired heating rates. The set-up was standardised employing various reference materials such as benzoic acid, acetanilide, sulphanilamide and 1-chloro 2:4 dinitrobenzene and the standard deviation in the measurements evaluated. It has also been used successfully for the determination of carbon in uranium carbide and carbon and hydrogen in some uranyl-#beta#-diketone-amine N-oxide complexes and in plutonium(IV) oxalate. (auth.).
One of the main challenges for a high energy {gamma}{gamma} collider is the high repetition rate required for the laser-electron-beam collisions to convert into high energy gamma beams. State-of-the-art, high power lasers have a much lower repetition rate than that of the electron pulses. It is therefore highly desirable that the same laser pulse can be reused. As an example, for NLC where beams collide at 120 Hz, within each collision cycle there are 90 electron bunches separated by 1.4 ns between successive bunches. We show, by invoking a recently invented laser optical box, that the laser pulses can be reused for the entire train of bunches within each collision cycle. ((orig.)).
One of the main challenges for a high energy #gamma##gamma# collider is the high repetition rate required for the laser-electron-beam collisions to convert into high energy gamma beams. State-of-the-art, high power lasers have a much lower repetition rate than that of the electron pulses. It is therefore highly desirable that the same laser pulse can be reused. As an example, for NLC where beams collide at 120 Hz, within each collision cycle there are 90 electron bunches separated by 1.4 ns between successive bunches. We show, by invoking a recently invented laser optical box, that the laser pulses can be reused for the entire train of bunches within each collision cycle. ((orig.)).
We report the performance of a micro gas turbine on biomass producer gas and mixtures of biomass producer gas with natural gas. The micro gas turbine delivers full power on gas mixtures with a heating value of at least 15 MJ/Nm{sup 3}. For gas of lower heating value, the maximum fuel gas flow limits the attainable power. The lower limit for stable operation is about 8 MJ/Nm{sup 3}. The gross efficiency of the micro gas turbine depends on output power but not on the gas heating value, within our measurement accuracy. Above 70% of full power, emissions of CO and NO are 40 and 10 times lower than those of a gas engine of similar size. At part load below 70% of full power, the micro gas turbine burner switches to a different operating mode ...
The most effective way to generate electricity out of biomass is the gasification and the use of the gas in a gas engine. The conversion of the organic carbon with the gasification of biomass is higher than 95 %. Depending on the gasification concept, the efficiency of gasifiers is found between 70 and 90 %. If the pyrolysis gas is used in a gas engine, an electric efficiency of about 26 % referring to the primary amount of energy can be obtained. With efficient gas cleaning (cleaning for tar and dust), pyrolysis gas is well qualified for engine combustion. Through modern state of engine controlling there are ways to have complete control of the fluctuations in the gas composition. Furthermore, the minor calorific value of offered wood gas poses no problem for turbo charged lean-burn gas engines. ...
This patent describes an electrodeless lamp. It comprises: a microwave cavity; a source of microwaves in communication with the cavity; a lamp envelope containing a plasma-forming medium mounted within the microwave cavity; a gas manifold for feeding gas to at least one gas passageway for directing a stream of gas to the outer surface of the envelope; a gas leak passageway leading from the gas manifold; a conductive mesh assembly for retaining microwaves within the cavity and permitting light to be emitted from the cavity. The assembly including gas flow blocking means for preventing the flow of gas through the gas leak passageway when the screen is in place in the lamp; and means for shutting off the source of microwaves when the gas pressure in the manifold drops below a ...
Appendices to this summary consist of twelve individual status reports that will be available through the National Technical Information Service (NTIS) in the United States and of course limited copies will be available through NATO. The twelve report titles which are appendices to the summary are: (A) Status Report on the Limestone/Sludge Flue Gas Desulfurization Process; (B) Status Report on the Lime/Sludge Flue Gas Desulfurization Process; (C) Status Report on the Double Alkali/Sludge Flue Gas Desulfurization Process; (D) Status Report on the Sea Water Scrubbing Flue Gas Desulfurization Process; (E) Status Report on the Limestone/Gypsum Flue Gas Desulfurization Process; (F) Status Report on the Lime/Gypsum Flue Gas Desulfurization Process; (G) Status Report on the Double Alkali/Gypsum Flue Gas Desulfurization Process; (H) Status Report on ...
Gas hydrates have impacted the oil and gas industry since 1934, when they were first found to plug pipelines. Today we know that in deep oceans and in permafrost, very substantial gas reserves are present in hydrated form. Concerns are being raised about in situ dissociation for both energy and greenhouse implications upon methane release. In Japan work is underway to consider the storage of carbon dioxide, concentrated in clathrates. This talk will deal with some basic questions. Why should we be interested in gas hydrates? What are gas hydrates? How do gas hydrates form? How might hydrates impact on the energy/environmental picture?
This book discusses the progress and problems of current interest in gaseous dielectrics and their use, with special emphasis on insulation in high-voltage transmission lines and substations. Topics covered include: basic physics of gaseous dielectrics; basic mechanisms; gas decomposition, reactions and toxicity; diagnostics and field probes; gases and mixtures for GIS transformers and circuit breakers; gaseous media for discharge chemistry and etching/corona; gas engineering for pulsed power and switching; gas breakdown under steep-fronted voltages; new developments in gas-insulated equipment and gas handling; gas/insulator interface/flashover; and quality control in testing gas-insulated equipment. Contains approximately 85 papers.
Gas hydrates are crystalline substances composed of water and gas, in which a solid-water-lattice accommodates gas molecules in a cage-like structure. Gas hydrates are globally widespread in permafrost regions and beneath the sea in sediment of outer continental margins. While methane, propane, and other gases can be included in the clathrate structure, methane hydrates appear to be the most common in nature. The amount of methane sequestered in gas hydrates is probably enormous, but estimates are speculative and range over three orders of magnitude from about 100,000 to 270,000,000 trillion cubic feet. The amount of gas in the hydrate reservoirs of the world greedy exceeds the volume of known conventional gas reserves. Gas hydrates also represent a significant drilling and production hazard. A fundamental question ...
Gas hydrates are crystalline substances composed of water and gas, in which a solid-water-lattice accommodates gas molecules in a cage-like structure. Gas hydrates are globally widespread in permafrost regions and beneath the sea in sediment of outer continental margins. While methane, propane, and other gases can be included in the clathrate structure, methane hydrates appear to be the most common in nature. The amount of methane sequestered in gas hydrates is probably enormous, but estimates are speculative and range over three orders of magnitude from about 100,000 to 270,000,000 trillion cubic feet. The amount of gas in the hydrate reservoirs of the world greedy exceeds the volume of known conventional gas reserves. Gas hydrates also represent a significant drilling and production hazard. A fundamental question ...
We report the performance of a commercial recuperated micro gas turbine on biomass producer gas and mixtures of biomass producer gas with natural gas. The biomass producer gas, obtained by gasification at 850{sup o}C with air at atmospheric pressure, contains about 7% H2, 17% CO, 15% CO2, 4% CH4, 2% other hydrocarbons, 2% H2O, and a balance of N2 and Ar from air. It has a net heating value of about 6 MJ/(Nm{sup 3}). The micro gas turbine delivers full power (30 kW{sub e}) on gas mixtures with a net heating value of at least 15 MJ/(Nm{sup 3}). For gas of lower heating value, the maximum fuel gas flow allowed by the fuel control unit limits the attainable power. At reduced power, the lower limit for stable operation is a net heating value of about 8 MJ/(Nm{sup 3}). The gross efficiency of the micro ...
Abstract High-mobility group box 1 (HMGB1), a damage-associated molecular pattern (DAMP) molecules, favors tissue regeneration via recruitment and activation of leukocytes and stem cells. Here we demonstrate, in a model of acute sterile muscle injury, that regeneration is accompanied by active reactive oxygen species (ROS) production counterbalanced and overcome by the generation of antioxidant moieties. Mitochondria are initially responsible for ROS formation. However, they undergo rapid disruption with almost complete disappearance. Twenty-four hours after injury, we observed a strong induction of MURF1 and atrogin-1 ubiquitin ligases, key signals in activation of the proteasome system and induction of muscle atrophy. At later time points, ROS generation is maintained by nonmitochondrial sources. The antioxidant response occurs in both regenerating fibers and leukocytes that express high levels of free thiols and antioxidant enzymes, such as superoxide dismutase ...
Numerical simulations show that box-shaped bulges of edge-on galaxies are not bulges: they are bars seen side-on. Therefore, the two components that are seen in edge-on Sb galaxies such as NGC 4565 are a disk and a bar. But face-on SBb galaxies always show a disk, a bar, and a (pseudo)bulge. Where is the (pseudo)bulge in NGC 4565? We use archival Hubble Space Telescope H-band images and Spitzer Space Telescope 3.6 #mu#m wavelength images, both calibrated to Two Micron All Sky Survey K_s band, to penetrate the prominent dust lane in NGC 4565. We find a high surface brightness, central stellar component that is clearly distinct from the boxy bar and from the disk. Its brightness profile is a Sersic function with index n = 1.55 #+-# 0.07 along the major axis and 1.33 #+-# 0.12 along the minor axis. Therefore, it is a pseudobulge. It is much less luminous than the boxy bar, so the true pseudobulge-to-total luminosity ratio of the galaxy is PB/T = 0.06 #+-# 0.01, much ...
The situation of natural gas in the Federal Republic of Germany is described, with particular emphasis on the advantages and consequences of natural gas supply. The brochure discusses the role of natural gas on the energy market, the reliability of natural gas supply, the environmental impacts, the energy-saving effect of natural gas, natural gas prices, the competitive strength of the German gas industry, and the long-term reliability of natural gas supply. (orig.) [German] Die Situation des Erdgases in der Bundesrepublik Deutschland wird beschrieben, wobei die wichtigsten Vorteile und Auswirkungen der Erdgasversorgung besonders hervorgehoben werden. Es geht um die Stellung des Erdgases im Energiemarkt, die Sicherheit der Energieversorgung, Umweltschutz, Energieeinsparung durch Erdgaseinsatz, Erdgaspreise, ...
Effects of combustion conditions on the critical calorific value of flame blowout were reported for low calorific gas on the assumption of using coal derived gaseous fuel. Further, calculations of adiabatic flame temperature by using chemical equilibrium calculation were conducted in order to get a possibility of increasing exit gas temperature of gas turbine combustor to 1,300 C for low calorific value gas fuel. As a result, effects of (1) fuel composition, (2) preheating fuel temperature, (3) calorific value, and (4) combustion air velocity and fuel nozzle diameter, on the critical calorific values of flame blowout were clarified. In increasing exit gas temperature of gas turbine combustor to 1,300 C when using low calorific value gas fuel, it is essential to get an advanced cooling technology for the gas turbine ...
The genetic type, source and charging history of natural gas in the Yulin gas field in the Ordos Basin have been studied by combining the carbon isotopic composition of natural gas and geochemical characteristics of light hydrocarbons with carbon isotope fractionation model results and fluid inclusion analysis. The carbon isotopic composition of methane and ethane in the Yulin gas field is relatively enriched in {sup 13}C with {delta}{sup 13}C{sub 1} values ranging from - 35.3 permille to - 29.8 permille (average value = - 32.4 permille) and {delta}{sup 13}C{sub 2} ranging from - 26.3 permille to - 23.5 permille (average value = - 24.8 permille). The C{sub 7} light hydrocarbons are predominated by methylcyclohexane, accounting for 65.8% to 80.9% (average value = 71.6%), which is characteristic of coal-derived gas. Furthermore, the gas geochemistry indicates ...
The production, principal applications, characteristics and properties, advantages of the gas natural is showed. A sectorial overview of the ceramic industry and the utilization of the natural gas in the ceramic industry is presented. The expectations are systematized and the impact of the natural gas utilization in the ceramic industry is evaluated. Some conclusions are withdrawn and recommendations suggested.
A combined gas/steam turbine process includes a high-pressure furnace and a high pressure gasification unit with a mounted upstream of a combustion chamber there is a gas turbine with a waste heat system. Combustion heat which is not needed to heat the flue gas to combustion temperature is released from the furnace and transferred to ths combustion air going into the combustion chamber.
Nomographs have been developed to simplify site performance estimates for various types of gas turbine engines used for industrial applications. The nomographs can provide valuable data for engineers to use for an initial appraisal of projects where gas turbines are to be considered. General guidelines for the selection of gas turbines are also discussed. In particular, site conditions that influence the performance of gas turbines are described.
The budding natural gas markets in East Europe attract a great deal of interest from natural gas industries in the Western countries. Dutch companies, institutions and the government, too, are active in this market. So far the results have not been spectacular. An analysis is made of the present situation and the Dutch approach
This article puts the case for coal fired combined cycle gas turbine (CCGT) power plants. The need to gasify the coal for the CCGT, use of fluidised bed combustors or gasification systems, the difference in prices of coal and natural gas, and coal and natural gas reserves are discussed. (UK)
Natural gas is essential to the world economy. Gas now accounts for almost a quarter of OECD primary energy requirements and is expected to become the second most important fuel in the world in the next decade. Industrial and residential consumers increasingly rely on natural gas to keep their houses warm, their lights on and their factories running. Meanwhile the gas industry itself has entered a new phase. Where gas used to be restricted to regional markets, it is now increasingly traded on a global scale. While gas production and transport requires long-term investment, now it is optimised on a short-term basis. Demand continues to grow, but local gas production has become much more expensive. How should we react? How will demand be satisfied? What changes are required to promote flexibility and trade? What are the implications for ...
Mist eliminators for flue gas desulphurisation units remove liquid droplets entrained in the flue gas leaving the SO/sub 2/-absorber vessels. The commercial designs currently available are described.
The purpose of this project was to build a long-range, parallel hybrid gas/electric vehicle capable of driving beyond the communter capabilities of series hybrid vehicles. It was envisioned that since the gas engine would be able to independently propel t...
Radon-222 has been measured in natural gas produced from experimental geopressured-geothermal test wells. Comparison with published data suggests that while radon activity of this unconventional natural gas resource is higher than conventional gas produced in the gulf coast, it is within the range found for conventional gas produced throughout the US. A method of predicting the likely radon activity of this unconventional gas is described on the basis of the data presented, methane solubility, and known or assumed reservoir conditions of temperature, fluid pressure, and formation water salinity.
BackgroundEmphysematous cholecystitis is a variant of acute cholecystitis which is generally caused by gas-forming organisms. Emphysematous cholecystitis may cause gas spreading...Full Text Available
... Accession Number : ADD135818. Title : Performance of Titanium in Flue Gas Desulfurization Scrubber Systems,. Descriptive Note : Journal Article,. ...
The properties of the ideal gas of classical (nonquantum) tachyons are considered. Starting from the definition of thermodynamic functions for this system, it may be found that tachyons and bradyons gases are similar. (AA).
A new surveillance system for Oil-Filled cable, which can provide continuous monitoring, using a newly developed optical gas sensor that can detect the concentration of the gas dissolved in the oil with extremely high sensitivity has been developed. It was proved that the degree of deterioration of the insulating oil can be detected by measuring C{sub 2}H{sub 2} and CH{sub 4} by investigating the relation between the degree of deterioration and amount of combustible gas generated. In order to detect extremely small amounts of gas, a new gas detecting method using absorption line of the gas using a frequency modulated technique has been developed. The gas detection ability was also confirmed by examination using a 66 kV of cable and the possibility of detection at an early stage is expected.
Rapid technology improvements, resulting in high efficiency, emissions reduction and low generation cost, are making gas turbines the generation technology of choice despite some recent reliability problems. The basic reason for the dominance is high efficiency. The rapid pace of gas-turbine technology improvement in the 1990s drove combined-cycle thermal efficiency to nearly 60 percent with natural gas as the fuel. It will probably go even higher after the year 2000. In addition, the gas-fired combined cycle is a bargain. With natural gas prices where they are right now, it is the least-cost generation operation for power producers with access to gas. Many will replace older, high-cost power plants with new gas-fired combined cycle power plants.
The oxygen production of a photosynthetic gas exchanger containing Chlorella pyrenoidosa (1% packed cell volume) was measured when various concentrations of carbon dioxide were present...Full Text Available
The purpose of this publication is to provide a better understanding of flue gas desulfurization. It provides brief answers to questions concerning its applicability, cost, effectiveness, and operation.
This bibliography contains 3920 references including abstracts, to information on the technology of flue gas desulfurization and denitrification. These references and others are included in the Department of Energy's Energy Data Base (EDB) through Decembe...
Tests to measure the maximum horsepower of commercial vehicles converted for use with natural gas fuel indicate a reduction of approximately 20% in horsepower compared with gasoline-driven vehicles. This reduction in horsepower resulting from the use of gas is due basically to the lower thermal efficiency of the cycle of natural gas compared with that of gasoline and to its lower volumetric efficiency, since natural gas is injected into the combustion chamber in gaseous form, unlike gasoline, in which part of the fuel entering the cylinder is in the liquid phase. Natural gas used as a fuel generates lower quantities of air pollutants, particularly unburned hydrocarbons (HCs) and carbon monoxide (CO). Despite the downside of reduced horsepower, the use of natural gas as a fuel for automotive vehicles equipped with Otto-cycle engines is economically viable owing ...
The natural gas industry has proposed an increase in the DOE gas R&D budget from about $100 million to about $250 million per year for each of the next 10 years. The proposal includes four programs: natural gas supplies, fuel cells, natural gas vehicles and stationary combustion systems. This paper is a qualitative assessment of the gas industry proposal and recommends a natural gas R&D strategy for the DOE. The methodology is a conceptual framework based on an analysis of market failures and the energy policy objectives of the DOE`s (1991) National Energy Strategy. This framework would assist the DOE in constructing an R&D portfolio that achieves energy policy objectives. The natural gas supply program is recommended to the extent that it contributes to energy price stability. Stationary combustion programs are supported on ...
Prepared to make housing project managers, maintenance engineering staff, and designers and architects of HUD - assisted and HUD - insured housing projects and mobile home parks aware of their responsibilities under the Natural Gas Pipeline Safety Act, this handbook provides technical guidance for the reduction of gas leaks and the handling of gas leak incidents in residential areas. The hazards of natural gas, concern over gas safety in residential areas, applicable codes and standards, and sources of information and help are reviewed, along with maintenance and engineering considerations relating to gas pipe failures, the detection of gas leaks, appliance servicing, and pipe installation, repair, and replacement. Housing management considerations are also examined, with attention to recordkeeping and reporting, emergency contingency ...
Gas Supplies of Interstate Natural Gas Pipeline Companies 1987 was prepared by the Reserves and Natural Gas Division, Office of Oil and Gas, Energy Information Administration (EIA). The publication provides information on the total reserves, production, and deliverability capabilities of the 87 interstate pipeline companies required to file the Federal Energy Regulatory Commission (FERC) Form 15, ''Interstate Pipeline's Annual Report of Gas Supply.'' This publication is the 25th in a series of annual reports on the total gas supplies of interstate pipeline companies since the inception of individual company reports to the Federal Power Commission (FPC) in 1964 for report year 1963. This publication provides information on the interstate pipeline companies' supply of natural gas during ...
The corrosion behavior of 304 stainless steel was characterized with cyclic voltammetry in a eutectic Li/K and Li/Na carbonate melt under anode and cathode gas of the molten-carbonate fuel cell (MCFC). The corrosion rate of 304 steel was determined in four different environments of the MCFC with electrochemical methods and from cross-sectional analysis of corrosion layers. These four environments were open-circuit and MCFC-load conditions both under anode and cathode gas. At open-circuit conditions corrosion was more severe under the oxidizing cathode gas then under the reducing anode gas. On the contrary, at load conditions corrosion was more severe under anode than under cathode gas. The anodic polarization under anode gas enhances corrosion, whereas the high anodic polarization under cathode gas leads to anodic protection. Corrosion ...
Austenitic stainless steels have been implanted with molybdenum ions (Mo[sup +], 100 keV, 2.5 x 10[sup 16] atoms cm[sup -2]). The implanted material has been characterized by XPS and RBS. The implanted region has a thickness of [approx] 1000 A with a maximum molybdenum concentration of [approx] 9 at.% Mo located at [approx] 210 A from the surface. The effects of implanted molybdenum on the passivation of the alloy in 0.5 M H[sub 2]SO[sub 4] have been investigated by electrochemistry and XPS. After XPS analysis the samples were transferred without exposure to air into a glove-box with an inert atmosphere. The electrochemical behaviour of the alloy is significantly modified by the implanted molybdenum. The major effect is that the activation peak disappears. A bilayer structure (outer hydroxide/inner oxide) of the passive film is observed for both the implanted and non-implanted alloys and the thicknesses of the films are similar. On the implanted alloy the outer ...
Austenitic stainless steels have been implanted with molybdenum ions (Mo"+, 100 keV, 2.5 x 10"1"6 atoms cm"-"2). The implanted material has been characterized by XPS and RBS. The implanted region has a thickness of #approx# 1000 A with a maximum molybdenum concentration of #approx# 9 at.% Mo located at #approx# 210 A from the surface. The effects of implanted molybdenum on the passivation of the alloy in 0.5 M H_2SO_4 have been investigated by electrochemistry and XPS. After XPS analysis the samples were transferred without exposure to air into a glove-box with an inert atmosphere. The electrochemical behaviour of the alloy is significantly modified by the implanted molybdenum. The major effect is that the activation peak disappears. A bilayer structure (outer hydroxide/inner oxide) of the passive film is observed for both the implanted and non-implanted alloys and the thicknesses of the films are similar. On the implanted alloy the outer hydroxide layer contains ...
Due to the fact that, the workers' behavior is characterized by its complexity and diversity, this issue has been seen as a great 'black box' in discussions regarding the Management Systems of SHE. Associated with this issue other arises: How conscious people? How to engage them with the process? How to improve the risk control? How to motivate the prevention? Most of these responses are discussed in the Social and Human Sciences for many years. However, it is necessary to closer the technical-operational knowledge and the human aspects, applying in the organizations' daily work, to make the working environment more safe. The purpose of this study, therefore, is examining the possibility of reducing accidents through the identification and treatment of deviations (unsafe acts and unsafe conditions), cause the whole accident, be it serious or not, begins with a small deviation. It was used as a reference tool, the Behavior audit ...
The He-shell flash convection in AGB stars is the site for the high-temperature component of the s-process in low- and intermediate mass giants, driven by the Ne22 neutron source. [...] The upper convection boundary plays a critical role during the H-ingestion episode that may lead to neutron-bursts in the most metal-poor AGB stars. We address these problems through global 3-dimensional hydrodynamic simulations including the entire spherical He-shell flash convection zone (as oposed to the 3D box-in-a-star simulations). An important aspect of our current effort is to establish the feasibility of our appoach. We explain why we favour the explicit treatment over the anelastic approximation for this problem. The simulations presented in this paper use a Cartesian grid of 512^3 cells and have been run on four 8-core workstations for four days to simulate ~5000s, which corresponds to almost ten convective turn-over times. The convection layer extends radially at the ...
Soil dressing on coal ash reclaimed land is a covering to use the land for agriculture. This study was carried out to find out the necessary depth of soil covering the ash layer in order to have normal crop growth. Two kinds of crops, Japanese radish, and rakkyo were planted in cover soil on the fly ash packed in wooden boxe (90 cm x 90 cm x 90 cm). Depths of cover soil were 20 cm, 30 cm, 40 cm and 50 cm. The results were summarized as follows: growth and yield of Japanese radish and rakkyo were increased with increasing depth of cover soil; root development of Japanese radish was inhibited at the lower coal ash layer. Main root length and edible root length of Japanese radish were decreased with decreasing depth of cover soil; boron and molybdenum contents in the plants remarkably increased with decreasing depth of cover soil. This may be due to the absorption of these elements from fly ash layer; it is concluded that optimum depth of cover soil should be more ...
A calculation program (URA 6.F4) was elaborated on FORTRAN IV language, that through finite differences solves the unidimensional scalar Helmholtz equation, assuming only one energy group, in spherical cylindrical or plane geometry. The purpose is the determination of the flow distribution in a reactor of spherical cylindrical or plane geometry and the critical dimensions. Feeding as entrance datas to the program the geometry, diffusion coefficients and macroscopic transversals cross sections of absorption and fission for each region. The differential diffusion equation is converted with its boundary conditions, to one system of homogeneous algebraic linear equations using the box integration technique. The investigation on criticality is converted then in a succession of eigenvalue problems for the critical eigenvalue. In general, only is necessary to solve the first eigenvalue and its corresponding eigenvector, employing the power method. The obtained results by ...
We present results from a large volume simulation of Hydrogen reionization. We combine 3d radiative transfer calculations and an N-body simulation, describing structure formation in the IGM, to detail the growth of HII regions around high redshift galaxies. Our simulation tracks 1024^3 dark matter particles, in a box of side length 65.6 Mpc/h. This large volume allows us to accurately characterize the size distribution of HII regions throughout most of the reionization process. At the same time, our simulation resolves many of the small galaxies likely responsible for reionization. It confirms a picture anticipated by analytic models: HII regions grow collectively around highly-clustered sources, and have a well-defined characteristic size, evolving from a sub-Mpc scale at the beginning of reionization to R>10 Mpc towards the end. We present a detailed statistical description of our results, and compare them with a numerical hybrid scheme based on the analytic ...
In the Institute for Atomic Energy, Rikkyo University, just after the TRIGA-2 research reactor of 100 kW has attained the criticality, the cylindrical box for neutron radiography (NR) irradiation was made in the attached pool, and the research on NR was started in 1961. Thereafter in 1985, the vertical irradiation pipe was installed in the reactor tank, and the experiment for collecting the basic data was begun. In 1986, based on the obtained data, the NR irradiation facility on full scale was installed in No. 2 tangential horizontal experimental hole. As the main NR irradiation facilities, the vertical neutron irradiation pipe, the use of which is stopped now, the NR facility using the horizontal experimental hole (RUR/N2), the irradiation facility and ancillary facilities such as beam shutter, beam catcher and hoist are described. As the main equipments for NR, the imaging apparatuses of cooled type CCD, SIT and superhigh sensitivity, the image processors of ...
We recently found that many RNA polymerase II transcription factors are modified with N-acetylglucosamine residues. These sugar moieties confer upon transcription factors an ability to bind the lectin wheat germ agglutinin. We have taken advantage of this interaction to devise a purification procedure for the "GC-box" binding transcription factor Sp1. Crude nuclear extracts are first subjected to wheat germ agglutinin affinity chromatography and then subjected to sequence-specific DNA affinity chromatography. The Sp1 protein purified by this procedure is at least 95% pure, and the overall recovery is greater than 80%. In addition to yielding larger quantities of Sp1 than conventional schemes, the new purification procedure is also simpler and more rapid. We show that wheat germ agglutinin affinity chromatography can also be used to purify the glycosylated forms of the CCAAT-binding transcription factor. Thus, wheat germ agglutinin affinity chromatography may aid ...
A new industrial process allowing to reach very high cooling rates in the cooling section after soaking of a continuous annealing line for steel sheets is presented. This process constitutes the successful conclusion of a long term research programme, jointly carried out at CRM and Arcelor Cockerill-Sambre for three years, including laboratory experiments, pilot scale trials and several industrial campaigns. It is running on from developments performed in the framework of the HOWAQ (Hot Water Quench) process. The process successively combines a moderate cooling step (600 deg C/s for 0.8 mm thick strips), in boiling water, and a faster cooling step (above 700 deg C/s), by impinging turbulent cold water in a box. Its main features are simplicity, resulting from advanced developments, soundness, flexibility and cooling homogeneity. As treated steel products are characterized by improved mechanical properties, outstanding surface quality (corrosion resistance) and ...
The synthesis of narrowly dispersed nanocrystalline TiO_2 was investigated with a surfactant aided solvothermal synthetic method in toluene solutions. When a sufficient amount of titanium isopropoxide, Ti[OCH(CH_3)_2]_4 (TIP), was added to the solution, the shapes of TiO_2 nanoparticles changed from spheres to rods. The aggregated microstructures of the nano-sized TiO_2 in systems of spheres, rods, and mixtures of spheres and rods was studied using TEM. The morphological shape of the aggregation was described in terms of the fractal dimensions. We used a box-counting method to get the fractal dimension of these systems. The fitted fractal dimensions for spheres, sphere/rod mixtures, and rods are D = 1.54, D = 1.81, and D = 1.89, respectively. The fractal dimension changed from 1.54 to 1.9 with the TIP/toluene ratio, indicating that the growth mechanism for aggregations showed different behaviors.
The characteristic space-time scales of surface solar radiation fields measured by the 111-instrument ME-SONET in Oklahoma are estimated after removal of the diurnal cycle. These estimates of {open_quotes}within-day{close_quotes} are used to deduce the representativeness of surface solar radiation measurements measurement site as a function of time-averaging interval. Nomograms of the relation between point measurements and area averages are given for different space-time-averaging intervals. Examples from the nomograms show, for instance, that under conditions of low mean radiation (cloudy days), the central site point measurements are representative of a spatial area the size of a T42 GCM grid box (280 km X 280 km) if one uses hourly averages and is willing to accept a correlation of 0.45 between area average and point measurement. The point data represent a 60 km X 60 km region at a 0.90 correlation level if a 5-min time average is used. The characteristic ...
Genetic mapping is approached using the techniques of high resolution fluorescence in situ hybridization (FISH). This technology and the results of its application are designed to rapidly generate whole genome as tool box of expressed sequence to speed the identification of human disease genes. The results of this study are intended to dovetail with and to link the results of existing technologies for creating backbone YAC and genetic maps. In the first eight months, this approach generated 60--80% of the expressed sequence map, the remainder expected to be derived through more long-term, labor-intensive, regional chromosomal gene searches or sequencing. The laboratory has made significant progress in the set-up phase, in mapping fetal and adult brain and other cDNAs, in testing a model system for directly linking genetic and physical maps using FISH with small fragments, in setting up a database, and in establishing the validity and throughput of the system.
The relationship between the fractal dimensions of spatial distributions of aftershocks and pre-existing active faults is examined. Fourteen mainshocks taking place in Japan were followed by aftershocks, and the aftershocks occur in swarms around the mainshocks. The epicentral distributions of the aftershocks exhibit fractal properties, and the fractal dimensions are estimated by using the two-point correlation integral. The pre-existing active fault systems observed in the 14 aftershock regions have fractal structures, and the fractal dimensions are estimated by using the box-counting method. A positive correlation between the estimated fractal dimensions is found, and it is independent on the mainshock magnitude. The correlation shows that aftershock distributions become less clustered with increasing the fractal dimensions of active fault systems. Namely, the fractal clusters of aftershocks are put under the constraint of the fractal properties of the ...
This peer-reviewed article from Bioscience journal is about restoring the Truckee river.Throughout the 20th century, the Truckee River that flows from Lake Tahoe into the Nevada desert was progressively dammed and dewatered, which led to the collapse of its aquatic and riparian ecosystems. The federal designation of the endemic cui-ui sucker (Chasmistes cujus) as endangered prompted a restoration program in the 1980s aimed at increasing spring flows to permit fish spawning. These flows did promote cui-ui reproduction, as well as an unanticipated benefit, the extensive seedling recruitment of Fremont cottonwood (Populus fremontii) and sandbar willow (Salix exigua). Recruitment was scattered in 1983 but extensive in 1987, when the hydrograph satisfied the riparian recruitment box model that had been developed for other rivers. That model was subsequently applied to develop flow prescriptions that were implemented from 1995 through 2000 and enabled further seedling ...
A computer-aided detection (CAD) system was evaluated for its ability to detect microcalcifications and masses on images obtained with a digital phase-contrast mammography (PCM) system, a system characterised by the sharp images provided by phase contrast and by the high resolution of 25-{mu}m-pixel mammograms. Fifty abnormal and 50 normal mammograms were collected from about 3,500 mammograms and printed on film for reading on a light box. Seven qualified radiologists participated in an observer study based on receiver operating characteristic (ROC) analysis. The average of the areas under ROC curve (AUC) values for the ROC analysis with and without CAD were 0.927 and 0.897 respectively (P = 0.015). The AUC values improved from 0.840 to 0.888 for microcalcifications (P = 0.034) and from 0.947 to 0.962 for masses (P = 0.025) respectively. The application of CAD to the PCM system is a promising approach for the detection of breast cancer in its early stages. (orig.)
The flux of cosmic ray antiprotons with kinetic energies between /approximately/1 and 15 GeV is /approximately/5 times greater than the flux predicted on the basis of the leaky-box model. This excess is attributed to secondary antineutron production in compact sources. Because the antineutrons are not confined by the magnetic field of the compact source, they leave the interaction site, decay in interstellar space and account for the apparent excess cosmic ray antiproton flux. The escape and decay of neutrons produced in association with the antineutrons is a source of cosmic ray protons. Observations of the angular variation of the intensity and spectral shape of 100 MeV ..gamma..-rays produced by neutron-decay protons in the reaction p + p ..-->.. ..pi../sup 0/ ..-->.. 2..gamma.. could reveal compact-source cosmic ray production sites. COS-B observations of spectral hardening near point sources, and future high-resolution observations of galactic point ...
Spam messes up user's inbox, consumes network resources and spread worms and viruses. Spam is flooding of unsolicited, unwanted e mail. Spam in blogs is called blog spam or comment spam.It is done by posting comments or flooding spams to the services such as blogs, forums,news,email archives and guestbooks. Blog spams generally appears on guestbooks or comment pages where spammers fill a comment box with spam words. In addition to wasting user's time with unwanted comments, spam also consumes a lot of bandwidth. In this paper, we propose a software tool to prevent such blog spams by using Bayesian Algorithm based technique. It is derived from Bayes' Theorem. It gives an output which has a probability that any comment is spam, given that it has certain words in it. With using our past entries and a comment entry, this value is obtained and compared with a threshold value to find if it exceeds the threshold value or not. By using this concept, we developed a software ...
Power plant components exposed to environments such as water and soil are susceptible to severe corrosion. Many times the effect of corrosion in power plant components can be catastrophic. The problem is aggravated for underground pipelines due to additional factors such as large network of pipelines, proximity to earth mat, high voltage transmission lines, corrosive chemicals, inadequate approach etc. Other components such as condenser water boxes, internals of pipelines, clarifier bridge structures, cooling water inlet gates and pipes etc. which are in continuous contact with water, are subjected to severe corrosion. The nature and locations of all such components are at places which are not accessible for routine maintenance and hence they require long term reliable protection against corrosion. Experience has shown that anti-corrosive coatings are inadequate in preventing corrosion and due to their location regular maintenance coatings are also not feasible. ...
A new small size gamma irradiator is being set up at Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Brazil, with a revolutionary design. The developed technology for this facility consists of continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m{sup 2} of floor area, the irradiator design is product overlap sources and the maximum capacity of Cobalt-60 wet sources is 37 PBq (1 MCi). The irradiator is being installed in a Governmental Institution and it will be used as a demonstration facility for manufacturers, who need an economic and logistic in-house irradiation system alternative. Also, it will be useful for supporting the local scientific community on development of products and process using gamma radiation, assisting the ...
Full text: Chemical-technology approaches allowing to intensification the prevention processes of gas hydrates formation at motion of gas-liquid stream of natural gas in system natural gas well - gas wire have been worked up. Technological regimes of treatment of gas stream have been determined. Linear correlation dependences inhibitor electrolytes contained hydrated ions with different ion radii and charges of subgroups of alkali elements with one - type electron configuration were obtained. Important physico-chemical parameters of electrolytes have been determined: activity; coefficients of activity, viscosity, diffusion; density; heat capacity; heat conductivity; surface tension and freezing-point. The features of continuous influence of inhibitory factors on process of gas flow at low temperatures and relatively high pressure differences ...
The passive continental margin in the northern South China Sea is a weakly active area. It has been found to be favorable for large gas field development and also to be profitable for gas hydrate. The active faults, diapir structure, slump deposits, faults break of slopes, gas chimneys and sandstone of submarine fan, control the concentration of gas hydrate. Gas chimneys are widely distributed in the northern South China Sea. They supply the pathway for migration of deeper gas to gas hydrate stability zones especially in the basin of tectonic inactive zone. This paper discussed the geological structures of gas hydrate occurrence in gas fields and presented a detailed analysis of gas chimneys within the northern slope of the South China Sea. The paper described the geological ...
The paper deals with a model in which the motion of a gas in plasma accerators and high-curent discharges in the present of a skin effect is treated as expulsion by a 'magnetic piston' under the action of surface current flow. Specifically examined is the situation where the initial gas pressure is negligible in comparison with the magnetic pressure, and the motion of the gas may be treated as a self-simulating one. A system of hydrodynamic equations of the problem is derived and integrated by Adam's method. Results are plotted and discussed.
Gas contaminated with at least one noxious component, such as SO/sub 2/, HF or NOx, is scrubbed with a clear, calcium-containing, initially-basic washing liquid which also comprises the anion of a strong inorganic acid, that of a polybasic carboxylic acid and, optionally, that of a monobasic carboxylic acid. Apparatus is provided for scrubbing the gas, oxidizing produced calcium bisulfite to calcium sulfate, separating out and removing solids, and recirculating clarified liquid for scrubbing contaminated gas.
The Rayleigh scattering length has been calculated for rare-gas liquids in the ultraviolet for the frequencies at which they luminesce. The calculations are based on the measured dielectric constants in the gas phase, except in the case of xenon for which measurements are available in the liquid. The scattering length mayplace constraints on the design of some large-scale detectors, using uv luminescence, being proposed to observe solar neutrinos and dark matter. Rayleigh scattering in mixtures of rare-gas mixtures is also discussed.
The fission gas xenon bonded in bubbles, in pore, and in the lattice of mixed carbide fuels is measured by electron-probe microanalysis. Radial xenon distribution and release curves are determined and are calibrated by gas chromatography of the bonded fission gas and by burnup analysis in the respective pin sections of the irradiation experiments FR2 6A and 6C, Mol 11/K 2, and DFR 330/1. The results are correlated to the microstructure of the fuel, bonding medium, temperature, and burnup. (Auth.).
Analysis of the coke gas combustion porcess is presented. Standard kinetic relationships were utilized. Calculations were performed for coke gas with high and low content of H/sub 2/ and for blasting air 20 and 100/sup 0/C. Temperature relationships, composition of gas combustion products and release of nitrogen oxides were determined. Results are analyzed which will make it possible to control the composition of combustion products.
This thesis dealt with the metal-organic gas phase epitaxy with nitrogen as carrier gas. For this first by means of three-dimensional modelings of the epitaxy process the influence of the carrier gas on the processes was explained. The optimization of the growth parameter for the whole light-emitting-diode structure in double-hetero arrangement resulted that an a temperature of 770 C and a V/ III-ratio of 150 layers with a high crystal quality could be reached.
Plasma with a gas temperature below room temperature is not yet fully understood although it is expected to be an attractive tool for applications to material processing. In the present work, gas-temperature-dependent generation of a cryoplasma jet was studied. So far, we have generated a helium cryoplasma jet (296-5 K) under atmospheric pressure. At gas temperatures below 20 K, the helium excimer, He2, was observed clearly from by optical emission spectroscopy.
The gas composition of recent thermal waters is in perfect conformity with their geologic-tectonic positions. The composition of gas-liquid inclusions in the basic-hyperbasic xenoliths of basaltoid lavas depends on the depth from which xenoliths are supplied. (The depth is determined by using the methods of geological thermobarometers). By comparing available data the conclusion was drawn that the gas compositions of thermal waters reflect the depth of generation of deep fluid which heats them and depends on the penetration depth of the fluid-conducting fissure zones.
Spark ignition internal combustion engines perform satisfactorily when the fueled with biomass producer gas from a fluidized bed gasifier. Although power output is reduced compared to natural gas levels, full power recovery can be achieved with a relatively low level of supercharging. Important considerations are an adequate fuel delivery system and adquate gas cleaning. ref.
... harassment, incidental to construction and operation of an offshore liquefied natural gas (LNG) facility. Under the Marine Mammal Protection ... ...
The primary objective of this study is to assess the oil and gas potential of the West Siberian Basin of Russia. The study does not analyze the costs or technology necessary to achieve the estimates of the ultimate recoverable oil and gas. This study uses reservoir data to estimate recoverable oil and gas quantities which were aggregated to the field level. Field totals were summed to a basin total for discovered fields. An estimate of undiscovered oil and gas, from work of the US Geological Survey (USGS), was added to give a total basin resource volume. Recent production decline points out Russia`s need to continue development of its discovered recoverable oil and gas. Continued exploration is required to discover additional oil and gas that remains undiscovered in the basin.
Details of a 1 day conference designed to create more efficient interactions between the gas supply and electricity systems in Ontario and new models for gas supply and the electricity system were presented. Market efficiency, generators' perspectives on critical gas issues, an overview of the North American gas and an outline of issues concerning Ontario were discussed. A natural gas industry forecast and issues concerning marketers and producers were presented. The terms on which gas is bought and sold were discussed. Regulatory tools, cost allocation and issues relating to unbundling were also presented. Infrastructure needs were reviewed, as well as basic market structures. It was suggested that appropriate commercial service options need to be developed and approved, including cross-utility services.
The Department of Energy has proposed a rulemaking process to set minimum standards for the efficiency of gas ranges under the National Appliance Energy Conservation Act (NAECA). The Gas Research Institute is compiling information on annual household range gas usage in order to prepare a response to the proposed rulemaking. The data base from the Northern Illinois Gas residential load study provides recent information (data taken from 1990 through 1992) over a comprehensive study of household types and appliance and user characteristics (150 variables noted for each household). The stated Objective is to study the Northern Illinois Gas residential load study data base and to evaluate its effectiveness in predicting annual household gas usage.
Research was performed to assess the feasibility of barrier membrane substances, for use within mining or associated high risk environments, in restricting the diffusion transport of radon gas quantities. Specific tests were conducted to determine permeability parameters of a variety of membrane materials with reference to radon flow capabilities. Tests were conducted both within laboratory and in-situ emanation environments where concentrations and diffusion flows of radon gas were known to exist. Equilibrium radon gas concentrations were monitored in initially radon-free chambers adjacent to gas sources, but separated by specified membrane substances. Membrane barrier effectiveness was demonstrated to result in reduced emanation concentrations of radon gas within the sampling chamber atmosphere. Minimum gas concentrations were evidenced where the barrier ...
The light gain due to S/sub 2/ molecules in a supersonically cooled gas mixture is calculated. The S/sub 2/ molecules formed due to the recombination of the sulfur atoms, and the combustion gas mixture was preheated in a precombustion chamber. Optimal gas flow and nozzle parameters are found which correspond to the highest possible light gain using Cs/sub 2/-Ar and S/sub 2/-Ar gas mixtures. The steady state gas flow in the nozzle was calculated, taking into account the chemical reactions in the one-dimensional approximation. It is shown that the maximum gain values vary in the 0.0001-0.002 range for gas pressures in the precombustion chamber in the range 10-100 atm. The optimal initial relative concentration of Cs/sub 2/ molecules and S/sub 2/ molecules are given. 32 references.
The use of natural gas in China is still relatively immature, as gas production only supplies a low percentage of the domestic energy system. In contrast, Chinese economy mainly relies on coal with a 67% share of the total primary energy supply. The environmental impact from this high coal dependence is significant and planners have sought for cleaner energy sources. Natural gas is both cleaner and generally more efficient than coal and gas consumption is rising quickly due to these facts. The growth tendency indicates that natural gas will become an important substitution for coal in some parts of the Chinese primary energy consumption. To quantify this tendency, this paper uses a system dynamics model to create a possible outlook. The results show that the gas consumption in China will c...
Biomass gasification provides the potential to efficiently and economically produce a renewable source of a clean gaseous fuel suitable for power generation or synthesis gas (syngas) applications. An important side benefit of the use of biomass is the effective minimization of the primary greenhouse gas, carbon dioxide (CO{sub 2}), by providing a means to close-loop the CO{sub 2} cycle. However, high molecular weight hydrocarbon constituents (tar) in the product gas from gasification can complicate the downstream uses of the gas. This paper discusses both the development of a low cost, disposable catalyst system that can eliminate these heavy hydrocarbons from the gas and the use of the catalyst in conjunction with the Battelle high-throughput gasification process for power generation and synthesis applications. (author)
The presence of an extraneous light gas must be taken into account in consideration of centrifugal separation of uranium isotopes, when there is inevitable leakage of such a gas through the gas sealant and/or leaking in from the atmosphere. Consideration is first given to the influence of the presence of the light gas on the maximum separative power. Then the basic equation for isotope separation containing a light gas is derived from Hirschfelder's diffusion equations. This equation is solved and the separative performance is expressed in terms of the shape factor and reflux parameter. The formulas for expressing the flow configurations of the gases are obtained for a simple model in which inflow and outflow prevail throughout the centrifuge. The corresponding equation for a model in which the gases flow in two concentric thin streams is also derived. It is concluded that the ...
A patent is claimed for a process by which a low-hydrogen gas containing at least 90 percent by volume of methane which is suited for natural gas substitution is produced by transformation of vaporizable hydrocarbons with the aid of steam in the presence of a catalyst containing nickel, at temperatures of 350 to 600/sup 0/C and at increased pressure. Hydrocarbons and steam are supplied to the reaction in mixed form with recycle product gas. Per kilogramme of hydrocarbons to be converted in the high btu gas reactor, less than 1 kilogramme of fresh steam is needed. High btu gas is fed back from the high btu gas reactor to the input end of the same via a gas cycle comprising a cooler, a carbon dioxide absorption device, and a saturator. Between the carbon dioxide absorption device and the saturator a product gas is branched ...
The performance of the gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator GARIS was investigated using 255No produced in the 238U(22Ne, 5n)255No reaction. Alpha particles of 255No separated with GARIS and transported by the gas-jet system were measured with a rotating wheel apparatus for ? spectrometry under low background condition. The high gas-jet efficiencies of about 75% were independent of the recoil ranges of 255No in the gas-jet chamber. The present results suggest that the GARIS/gas-jet system is a promising tool for the next-generation superheavy element chemistry: (1) the background radioactivities of unwanted reaction products are strongly suppressed, (2) the intense beam is absent in the gas-jet chamber and hence the high gas-jet efficiency is achieved, and (3) the beam-free ...
The purpose of this study is to identify the radiative heat transfer augmentation by a coaxial cylinder introduced in the infinite cylindrical pipe enclosing a participating gas. The gas is either a mixture of water vapor and carbon dioxide or gray. The gas is assumed to be homogeneous at a constant temperature, and has a refractive index of unity. All of the surfaces are opaque and gray, diffusely emitting and reflecting at a constant temperature. The effect of system diameter, diameter ratio, wall emittances, gas and surface temperatures, mixture component on heat transfer augmentation are studied by using the zone method with participating gas radiative properties evaluated from the weighted sum of gray gases model. From the radiative equilibrium condition, the installed wall temperature is formulated and calculated by the iteration method. If the medium is a gray ...
Visible smoke of exhaust gas from iron ore sintering plants spoil the scenery around the works. In this paper, the mechanism of formation of visible smoke is discussed by detailed analysis of the exhaust gas components and dust in the Oita No. 1 sintering plant. The main substance of visible smoke was mist condensing in the air during the cooling of exhaust gas that contained 0.1 ppm of sulfuric acid. Sulfuric acid is considered to raise the dew point and so facilitate mist condensation, and to lower the vaporization of visible mist containing sulfuric acid solution. Dust in the exhaust gas is also considered to act as nucleation sites for mist condensation. This proposed mechanism was confirmed by the test remixing SOx-rich gas with desulfurization gas in the Nagoya No. 3 sintering plant. Long trails of visible smoke were observed by remixing SOx-rich ...
Pressurized fluidized bed combustion (PFBC) is an emerging coal-fired, combined-cycle power generation technology nearing commercial status through several operating and planned demonstration plants throughout the world. Current-generation PFBC plants use ``ruggedized`` gas turbines that can tolerate dust loading common with conventional cyclone gas cleaning. The next generation of PFBC will apply advanced hot gas cleaning systems that will reuse the dust loading to low levels acceptable to high performance, industrial gas turbines. These advances should result in performance and cost advantages. This article examines the demonstration of PFBC technology at Tidd power station.
Sigma 1) examines ways to reduce the number of breakdowns of pressure-regulating stations and to minimize the energy consumed in warming the gas, 2) determines the optimal gas temperatures upstream from the pressure reduction, and 3) shows the dependence of energy consumption upon the water dewpoint. The method of calculating the optimal input temperature relies on Mollier's diagram. Tables and nomographs for natural gas and water dewpoint at 19/sup 0/F and 580 psi (-7/sup 0/C and 4 MPa) are useful in achieving the desired gas temperatures. Heating the regulators' control valves is important.
A study was conducted to examine the energy consumption in existing and new hog farming facilities and to analyse the potential for increased natural gas use in the Saskatchewan hog industry. Existing heating/cooling, ventilation and feed mill equipment choices offer possibilities for running on electricity, natural gas or propane. Energy costs are lowest when natural gas is used. To put the study in context, an overview of the Saskatchewan hog industry was provided. The potential increase in natural gas use in hog production by year 2005 was estimated. 10 refs., 6 tabs., 8 figs.
Increased use of natural gas has positive effects for the environment and the climate, because it primarily replaces petroleum products. Moreover, the natural gas does not pose a threat to bio fuel in Norway. But introducing CO2 taxes on natural gas will significantly increase the emission of greenhouse gases, concludes a report conducted by Norsk Energi (Norwegian Energy) on behalf of Norsk Naturgassforening (Norwegian Natural Gas Association) and Norsk Gassforum (Norwegian Gasforum). A brief presentation of the main conclusions in the report (ml)
National Power is building its first gas turbine combined cycle power station at Killingholme, situated to the south of the River Humber in the East of England. NEI ABB Gas Turbines Limited was awarded the turnkey contract in July 1990 to build a nominal 650 MW combined cycle power station based around three Asea Brown Boveri GT13E gas turbines. The project is outlined in this article. The plant is due for completion in July 1993. (author)
This article outlines the use of gasifiers during World War II and how, with soaring fuel prices, producer gas may provide an alternate energy path for agribusiness and farms today. In the last few years, the University of California has become a focus of producer gas research in the US. Biomass fuels used include crushed walnut shells, fruit pits, cereal straw and corn cobs. Particle size, moisture content and slagging create problems and the right kind of gas producer must be used to obtain reliable conversion to producer gas.
The objective of this contract is to research, develop and demonstrate a novel ceramic membrane reactor system for the low-cost conversion of natural gas to synthesis gas and hydrogen for liquid transportation fuels: the ITM Syngas process. Through an eight-year, three-phase program, the technology will be developed and scaled up to obtain the technical, engineering, operating and economic data necessary for the final step to full commercialization of the Gas-to-Liquids (GTL) conversion technology. This report is a summary of activities through February 1999.
The objective of this contract is to research, develop and demonstrate a novel ceramic membrane reactor system for the low-cost conversion of natural gas to synthesis gas and hydrogen for liquid transportation fuels: the ITM Syngas process. Through an eight-year, three-phase program, the technology will be developed and scaled up to obtain the technical, engineering, operating and economic data necessary for the final step to full commercialization of the Gas-to-Liquids (GTL) conversion technology. This report is a summary of activities through September 1999.
The waste tail gas fuel emitted from refinery plant in Taiwan e.g. catalytic reforming unit, catalytic cracking unit and residue desulfurization unit, was recovered and reused as a replacement fuel. In this study, it was slowly added to the fuel stream of a heater furnace to replace natural gas for powering a full-scale distillation process. The waste tail gas fuel contained on average 60 mol% of hydrogen. On-site experimental results show that both the flame length and orange-yellowish brightness decrease with increasing proportion of waste gas fuel in the original natural gas fuel. Moreover, the adiabatic flame temperature increases as the content of waste gas fuel is increased in the fuel mixture since waste gas fuel has a higher adiabatic flame temperature than that of natural gas. The complete replacement of natural ...
This paper provided an outline of the Canadian natural gas commodity market and a forecast for Canadian natural gas supply and prices for the 2007 winter heating season. Since 2001, steady demand growth and slow supply growth have contributed to higher North American natural gas commodity prices. The loss of natural gas supply due to hurricanes pushed North American natural gas commodity prices to record levels in 2005. Canadian natural gas production levels currently exceed domestic gas consumption. In 2005, Canada produced 16.5 billion cubic feet per day of marketable natural gas. Approximately 45 per cent was consumed domestically, and the remainder was exported to the United States. Despite high levels of drilling activity, production of natural gas from western Canada has flattened out since ...
The State of the Espirito Santo will become until the end of 2008, one of the main producers and natural gas exporters of Brazil, where, according to PETROBRAS, the State will produce about 20 million /day m{sup 3}, what it will go to contribute significantly for reduction of the dependence of the Bolivian gas, and still to give support to the natural gas sector in Brazil. The Intention of this work, is to identify proposals so that it has left of the gas produced in the State of the Espirito Santo, has a differentiated price. It does not make sensible the State to pay for the gas that is removed in its proper territory the same price that paid Sao Paulo for the gas that consumes imported of national Bolivia. With the markdown of the gas the State will be able to attract investments of great transport, to generate job and income and to ...
We have used the SINFONI integral field spectrograph to map the near-infrared K-band emission lines of molecular and ionised hydrogen in the central regions of two cool core galaxy clusters, Abell 2597 and Sersic 159-03. Gas is detected out to 20 kpc from the nuclei of the brightest cluster galaxies and found to be distributed in clumps and filaments around it. The ionised and molecular gas phases trace each other closely in extent and dynamical state. Both gas phases show signs of interaction with the active nucleus. Within the nuclear regions the kinetic luminosity of this gas is found to be somewhat smaller than the current radio luminosity. Outside the nuclear region the gas has a low velocity dispersion and shows smooth velocity gradients. There is no strong correlation between the intensity of the molecular and ionised gas emission and either the radio or ...
Nova Corporation and its related businesses are involved in natural gas production, gas pipelines, consulting services, and upgrading of natural gas into chemicals and plastics. Nova owns Alberta Gas Transmission Division, the primary gas transportation system in Alberta, with 11,400 miles of pipeline and total deliveries in 1992 of 3.4 trillion ft"3. Nova also owns 50% of Foothills Pipe Lines Ltd., one of Canada's largest carriers of exported gas, and 50% of TQM Pipeline Partnership, which transports natural gas in Quebec. Nova conducts its chemicals business through Novacor Chemicals Ltd., which has plants in Alberta, Ontario, Quebec, and the USA. Novacor's major petrochemicals are methanol, ethylene, propylene, and styrene and its major plastics are polystyrene, polypropylene, and polyethylene. Nova's gas-producing ...
Gas transmission pipelines are susceptible to both internal (gas side) and external (soil side) corrosion attack. Internal corrosion is caused by the presence of salt laden moisture, CO{sub 2}, H{sub 2}S, and perhaps O{sub 2} in the natural gas. Internal corrosion usually manifests itself as general corrosion. However, the presence of chlorides in entrained water also can lead to pitting corrosion damage. The electrochemical noise technique can differentiate general from localized corrosion and provide estimates of corrosion rates without external perturbation of the corroding system. It is increasingly being applied to field and industrial installations for in situ corrosion monitoring. It has been used here to determine its suitability for monitoring internal and external corrosion damage on gas transmission pipelines. Corrosion measurements were made in three types of environments: (1) aqueous ...
Short-lived fission gas release from fuel pellets during irradiation was investigated based on the experimental results of the gas-flow rigs irradiated in the Halden Heavy Water Reactor (HBWR). The release-to-birth (R/B) rates of short-lived fission gas were measured by means of gas-flow measurement during the irradiation experiments. Surface-to-volume (S/V) ratios of fuel pellets and diffusion coefficients of short-lived fission gas release were evaluated from the obtained (R/B) values. The increase of (S/V) ratio agreed well with the point where the fuel temperature exceeded the threshold of 1% fission gas release. This indicates that the interlinkage of fission gas bubbles occurred there. The evaluated diffusion coefficients scattered in the range between 10"-"2"3 and 10"-"1"7 m"2/s, and the effects of fuel type (UO_2 or MOX) were not ...
The European gas market is continuing to expand due to increased industrial, domestic and power generation demand. As a result of this demand, and the trend toward liberalization of the market, the need for storage of gas is also increasing. One key segment of the large scale storage of gas is underground storage, either in partially depleted gas or oil fields, naturally occurring caverns, aquifers and salt cavities. In most cases the gas produced after storage requires conditioning to meet the water of hydrocarbon dew point specification of the gas transmission system. For that reason export gas from storage will require gas conditioning in order to meet pipeline specifications. Adsorption as a feasible and reliable process will be presented in detail and especially in regards to hydrocarbon dew-pointing compared with ...
Geologically estimated natural gas resources are 500 Tcm. With the advance in geological science increase of estimated resources is expected. Natural gas reserves in 2000 have been proved to be around 165 Tcm. As it is known the reserves are subject to two constraints, namely: capital invested in the exploration and drilling technologies used to discover new reserves. The natural gas scarcity factor, i.e. ratio between available reserves and natural gas consumption, is around 300 years for the last 50 years. The new discovery of natural gas reserves has given rise to a new energy strategy based on natural gas. Natural gas utilization is constantly increasing in the last 50 years. With new technologies for deep drilling, we have come to know that there are enormous gas resources available at relatively low price. These ...
Geologically estimated natural gas resources are 500 Tcm. With the advance in geological science increase of estimated resources is expected. Natural gas reserves in 2000 have been proved to be around 165 Tcm. As it is known the reserves are subject to two constraints, namely: capital invested in the exploration and drilling technologies used to discover new reserves. The natural gas scarcity factor, i.e. ratio between available reserves and natural gas consumption, is around 300 years for the last 50 years. The new discovery of natural gas reserves has given rise to a new energy strategy based on natural gas. Natural gas utilization is constantly increasing in the last 50 years. With new technologies for deep drilling, we have come to know that there are enormous gas resources available at relatively low price. These ...
Two-phase flow in horizontal parallel channels has been experimentally investigated under fuel cell related operating conditions. Pronounced hysteresis is observed in the pressure drop versus flow characteristic curve when starting from either flooded or dry conditions. When gas is introduced into channels initially filled with water (flooded initial condition), both gas and liquid tend to flow predominantly in one channel at low gas or liquid flow velocities. As the gas flow velocity increases, even distribution of gas and liquid flow in both channels is observed, accompanied with a sudden decrease in the pressure drop. On the other hand, even gas and liquid flow distribution between both channels is found at comparatively lower gas flow velocities when starting with dry-gas flow conditions with liquid introduced into ...
A report is given of a meeting of the Netherlands Association for Energy Legislation (NEVER), which was held in Amsterdam, Netherlands, April 2006. After the meeting a presentation was made about the report 'Government involvement in liberalised gas markets. A welfare-economic analysis of the Dutch gas-depletion policy' of the Netherlands Bureau for Economic Policy Analysis (CPB). This report analyses the welfare effects of two major components of the Dutch gas-depletion policy: the offtake guarantee for small-fields gas and the cap on production from the Groningen field. After the presentation a reaction was given to the report. Both presentations give an overview of the governmental policy and insight in the effects.
A high-density gas jet supersonic nozzle is reported in this paper. The jitter and actuation time of the nozzle is determined by the pin discharge and laser spark radiation respectively. The jitter time of the nozzle is within 10 ?s with the backing pressure as high as 25 bar. With a nanosecond laser pulse focused on the gas jet about 1 mm below the nozzle, the actuation time is calculated to be about 15 ms by detecting the laser produced spark radiation, which reveals the existence of the gas jet and the relative gas density evolving with time. Consequently the gas density is estimated to be well above 1019 cm-3, compared with theoretical simulations from the nozzle parameters.
Some aspects of the PSO scheme for natural gas are examined critically. Two central arguments used for justifying the PSO subsidy scheme of natural gas and its distribution are reviewed; these include the 'smallholder argument' and the 'environmental argument'. The 'smallholder argument' claims that since Norway has the natural gas resources, it should also make use of the natural gas in the country, and not simply send the raw material to other countries. The 'environmental argument' states that natural gas compared to other fossil fuels such as coal and fuel oil, is a far cleaner alternative, thus an environmental-friendly alternative entitled to financial support. The arguments are critically examined by the author (ml)
We report on the discovery of kinematic shock signatures associated with a localized radio jet interaction in the merging Seyfert galaxy NGC 5929. We explore the velocity-dependent ionization structure of the gas and find that low-ionization gas at the interaction site is significantly more disturbed than high-ionization gas, which we attribute to a local enhancement of shock ionization due to the influence of the jet. The characteristic width of the broad low-ionization emission is consistent with shock velocities predicted from the ionization conditions of the gas. We interpret the relative prominence of shocks to the high density of gas in the nuclear environment of the galaxy and place some constraints of their importance as feedback mechanisms in Seyferts.
Natural gas is a promising alternative fuel to meet strict engine emission regulations in many countries. Natural gas engines can operate at lean burn and stoichiometric conditions with different combustion and emission characteristics. In this paper, the operating envelope, fuel economy, emissions, cycle-to-cycle variations in indicated mean effective pressure and strategies to achieve stable combustion of lean burn natural gas engines are highlighted. Stoichiometric natural gas engines are briefly reviewed. To keep the output power and torque of natural gas engines comparable to those of their gasoline or Diesel counterparts, high boost pressure should be used. High activity catalyst for methane oxidation and lean deNOx system or three way catalyst with precise air-fuel ratio control str...
During the 1990's, natural gas was the energy source with the fastest rate of growth in the world energy balance. Nevertheless, recent evolutions of the energy context, in particular in terms of prices, have had a rather strong impact on the progress of the different energy sources penalizing gas a little. Beyond this competition between energies, which may increase, the medium-term perspectives of natural gas development is in keeping with an environment full of uncertainties. This article presents: the world supply and demand prospects for 2010-2015 (impact of high gas prices on other energy sources, occurrence of production constraints, political decisions of producing countries and world gas industry balance), trends on main markets (North America, Europe, Asia-Oceania), and international trade. (J.S.)
An increasing share of natural gas supplies distributed to residential appliances in the U.S. may come from liquefied natural gas (LNG) imports. The imported gas will be of a higher Wobbe number than domestic gas, and there is concern that it could produce more pollutant emissions at the point of use. This report will review recently undertaken studies, some of which have observed substantial effects on various appliances when operated on different mixtures of imported LNG. While we will summarize findings of major studies, we will not try to characterize broad effects of LNG, but describe how different components of the appliance itself will be affected by imported LNG. This paper considers how the operation of each major component of the gas appliances may be impacted by a switch to LNG, and how this local impact may affect overall safety, performance and pollutant emissions.
The 575-mile Statpipe gas transportation system entails 191 miles of wet-gas line running from the Statfjord field across the Norwegian trench to the Karsto, Norway, conditioning plant and 384 miles of dry-gas line from Karsto, again across the trench, to the Heindal and Sleipner fields for final connection at Ekofisk with the Norpipe system for transport to Emden, West Germany. Special construction considerations include the 1000-ft-deep trench crossings, the rocky shore approach and departure, and the subsea tie-ins required at depths of up to 500 ft. The system has an initial annual design capacity of 186 billion CF of wet gas and 260 billion CF through the dry-gas line to Emden.
The Sulige gas field and the Yulin gas field are located in the north of the Ordos Basin. Reservoir pressure in the Sulige area is subnormal, whereas reservoirs in the Yulin area have normal hydrostatic pressure. This paper provides an explanation of this difference. The characteristics of reservoir sediment and formation water chemistry in the gas reservoirs of these two areas were analyzed. The results showed that both reservoirs have good sealing ability. Data of numerical simulation showed that tectonic uplift resulted in a great reduction in formation pressure in the northern Ordos Basin during the late Cretaceous period, and the decrease was greater in the Yulin gas field than in the Sulige gas field. However, because the total hydrocarbon-generating intensity of the Sulige area (<24...
The Granger instantaneous-causality test is applied to explore the potential causal relationships between wholesale electricity and natural-gas prices in California. The test shows these relationships to be bi-directional, and reveals California's electricity and natural-gas markets to be as inextricably intertwined as casual observation and theoretical considerations would suggest they ought to be. This meshing of markets exacerbated the effects of California's natural-gas crisis on the contemporaneous electricity crisis, while concurrently the electricity crisis may have contributed to the dysfunction in the national-gas market and helped to precipitate the natural-gas crisis. The finding supports an integrated approach, as opposed to a piecemeal approach, for formulating energy policy recommendations, not just in California but in the world at large. (author)
The Granger instantaneous-causality test is applied to explore the potential causal relationships between wholesale electricity and natural-gas prices in California. The test shows these relationships to be bi-directional, and reveals California's electricity and natural-gas markets to be as inextricably intertwined as casual observation and theoretical considerations would suggest they ought to be. This meshing of markets exacerbated the effects of California's natural-gas crisis on the contemporaneous electricity crisis, while concurrently the electricity crisis may have contributed to the dysfunction in the national-gas market and helped to precipitate the natural-gas crisis. The finding supports an integrated approach, as opposed to a piecemeal approach, for formulating energy policy recommendations, not just in California but in the world at large.
In this study the technical and economical possibilities of burning carbon monoxide (CO) of the flue gas and utilizing of the released heat in hot air cupola furnace used for melting have been studied. As basis for examining was burning of cleaned furnace...
The paper is an overview of utility flue gas desulfurization (FGD) technology and costs. The two commercially offered throwaway and salable product systems that are considered to be the most important for near-term (through 1990) SO2 control are: throwawa...
This patent describes a method of improving the S0{sub 2} scrubbing efficiency of flue gas desulfurization scrubbers. It comprises conducting the scrubbing operation in such scrubbers in the presence of an oil-soluble surfactant.
Gas turbine component protection remains essential but environmental regulations emphasize the gas-turbine efficiency. Heating and cooling are features often integrated into the GI air intake packages to provide the optimum operating conditions. This paper describes modern inlet air treatment systems and discusses their effectiveness. (author)
The structure of the skin in the epauletted fruit bat (Epomophorus wahlbergi) wing and body trunk was studied with a view to understanding possible adaptations for gas metabolism and...Full Text Available
The genetic type, source and charging history of natural gas in the Yulin gas field in the Ordos Basin have been studied by combining the carbon isotopic composition of natural gas and geochemical characteristics of light hydrocarbons with carbon isotope fractionation model results and fluid inclusion analysis. The carbon isotopic composition of methane and ethane in the Yulin gas field is relatively enriched in ^1^3C with d^1^3C1 values ranging from -35.3%% to -29.8%% (average value=-32.4%%) and d^1^3C2 ranging from -26.3%% to -23.5%% (average value=-24.8%%). The C7 light hydrocarbons are predominated by methylcyclohexane, accounting for 65.8% to 80.9% (average value=71.6%), which is characteristic of coal-derived gas. Furthermore, the gas geochemistry indicates that, although marine lime...
The Bureau of Mines performed chemical research to elaborate details of sulfur chemistry pertaining to the citrate flue gas desulfurization process in which sulfur dioxide (SO2), absorbed (as bisulfite ion) in a buffered sodium citrate solution, is reduce...
This report gives the results of a survey of operational flue gas desulfurization (FGD) systems on coal-fired utility boilers in the United States. The FGD systems installed on Units 1 and 2 at the Bruce Mansfield Station of the Pennsylvania Power Company...
A catalytic process for the oxidation of sulfur-containing gases , E.G., sulfur dioxide and simultaneous production of sulfuric acid wherein a sulfur-containing gas is reacted with an oxygencontaining gas in the presence of a catalyst comprising an iron group metal on a solid support comprising a zeolite in a silicaalumina matrix.
Gas exchange between the plant and the environment is severely hampered when plants are submerged, leading to oxygen and energy deficits. A straightforward way to reduce these shortages of oxygen and...Full Text Available
TSS (thermal swing sublimation) method was studied which uses vaporization heat and sensible heat of LNG for solidification and separation of CO2 gas in waste gases of LNG-fired combined cycle power generation system. In experiment, the mixed gas composed of CO2, H2O and N2 was used for simulating waste gas of LNG-fired combined cycle power generation systems, and the growth behavior of ice and dry ice was studied for developing dry ice making technology under low-temperature condition. As the experimental result, the following were clarified: various crystal structures depending on cooling temperature, the effect of gas flow rate on peeling of surface precipitated solids, and solidification characteristics of H2O/CO2 mixed gas. The growth rate of precipitated solid film thickness decreased with an increase in gas flow rate, while increased with CO2 ...
Limestone slurry needs to move efficiently through a complex process, meaning that selecting the right pumps and valves is critical. The article discusses factors to consider in selecting pumps and values for flue gas desulfurization process in coal-fired power plants. 2 photos.
The possibility has been explored of using a laser scattering technique to detect the imminent onset of rock activity associated with gas outbursts. The instrument described in this paper provides a sensitive, remote and rapid means of passively monitoring micro-seismic activity at the exposed face.
Petroleum is the unchallenged energy market leader in West Germany,having a share of 42%; natural gas accounts for 16-17%. West Germany imports 29% of its natural gas from the Soviet Union, 28% from the Netherlands, 14% from Norway, and 1% from Denmark. In West Germany many-branched natural gas distribution system is operated, equipped with a.o. 21 installations for underground storage which results in a great flexibility of the system. Because of the preferential treatment given to the use of coal as fuel for power plants the share of natural gas has decreased to the present 6% in the last ten years. In the indutrial sector the share is 18%. Strict air pollution abatement measures ('TA-Luft') favour the use of natural gas. However, duty has been levied on the use of natural gas per January 1st, 1989. For space heating of houses and commercial ...
The Monthly Energy Review provides an overview of the production, distribution, and consumption of energy derived from petroleum natural gas, coal, electricity, and nuclear energy. It also discusses oil and gas resource development, energy prices, and issues relevant to international energy markets.
This report presented some quick facts about oil and gas pipelines in Turkey and presented opportunities for trade. The key players and customers in the oil and gas sector were described along with an export check list. Turkey is looking into becoming an energy bridge between oil and gas producing countries in the Middle East, Central Asia and Europe. The oil and gas sectors are dominated by the Turkish Petroleum Corporation, a public enterprise dealing with exploration and production, and the State Pipeline Corporation which deals with energy transmission. They are also the key buyers of oil and gas equipment in Turkey. There are several pipelines connecting countries bordering the Caspian Sea. Opportunities exist in the areas of engineering consulting as well as contracting services for oil and gas pipeline transmission and distribution. Other opportunities ...
The report gives results of the measurement of dissolution rates of reagent CaCO3 and commercial limestones (9 types/19 grinds) at constant pH and solution composition by batch titration with HC1. Conditions were selected to simulate flue gas desulfurizat...
The influence of geometry and operating conditions of the centrifugal compressor stage on the radial gas force is determined on the basis of the theoretical method and calculation program using experimental boundary conditions.
... Radon gas concentrations are measured using instruments with calibrations traceable to the UK National Physical Laboratory and PTB, Germany. The primary facility is a 43 m3 walk-in chamber accessed by an airlock. Radon gas is maintained at a level in this chamber that is ...
The various steps of gas treatment in the Sasol II coal liquefaction plant are discussed: CO/sub 2/ removal, separation of the hydrocarbon fractions and the recirculated hydrogen by low-temperature decomposition, production of pure hydrogen by alternating pressure absorption.
Jeltes, R., Burghardt, E., and Breman, J. (1971). Brit. J. industr. Med., 28, 96-99. Gas chromatographic determination of phosgene and dichloroacetylene in air. Phosgene and dichloroacetylene...Full Text Available
An experimental investigation of heat transfer characteristics for various configurations of air jets impinging on the leading edge inner surface of a gas turbine blade wall is presented. Three configurations were investigated, namely a slot jet, a round ...
The goal of GRI's Gas Appliance Technology Center is to encourage the introduction of highly efficient, cost-effective, convenient gas appliances for residential and commercial gas users. The report covers activity at Battelle from February 1989 to April 1990 in broad support tasks, residential and commercial appliances, and residential space conditioning. Broad support tasks included the G/A/S Newsletter; the GATC InfoBase; and technology transfer, workshops, and GATC coordination. Residential appliance tasks included burner technology research, gas appliance venting, gas lighting, and plastics durability. Commercial appliance tasks included development of a commercial cooktop fuel/air mixing valve. Residential space conditioning tasks included a corrosion test method for gas appliances and vents, generic technology for condensing ...
This paper summarizes the current scientific and technological knowledge about greenhouse gas emissions from various agricultural practices and the manufacturing of food. The study also provides estimates that compare agriculture-related alternatives for reducing greenhouse gas emissions.
Legal aspects of using natural gas as boiler fuel for electric utilities are reviewed through one utility's challenges to the Power Plant and Industrial Fuel Use implementation. ASARCO vs. FPC, 1973, and City of Willcox vs. FPC are discussed. (PSB)
The report, generated by a computerized data base system, presents a survey of operational and planned domestic utility flue gas desulfurization (FGD) systems, operational domestic particle scrubbers, and Japanese coal-fired utility FGD installations. It ...
The report presents detailed technical information concerning application of flue gas desulfurization (FGD) systems to industrial boilers. The information was obtained by a survey of plant personnel, control system vendors, regulatory agencies, and consulting engineering firms. T...
The report discusses the capabilities of equipment vendors to supply and install the quantity of flue gas desulfurization systems required to meet alternative standards for coal-fired steam generators. It analyzes limiting factors affecting supply capabilities (such as the availa...
The effects of freeze-thaw cycling on the strength and durability of samples of compacted, stabilized, wet flue gas desulfurization (FGD) by-products are reported. The results of laboratory tests show a clear relationship between higher water contents and...
NO[sub x] emission legislation requirements for large-bore internal combustion engines have required engine manufacturers to continue to develop and improve techniques for exhaust emission reduction. This paper describes the development of the Cooper-Bessemer Clean Burn gas-diesel (dual-fuel) engine that results in NO[sub x] reductions of up to 92 percent as compared with an uncontrolled gas-diesel engine. Historically, the gas-diesel and diesel engine combustion systems have not responded to similar techniques of NO[sub x] reduction that have been successful on straight spark-ignited natural gas burning engines. NO[sub x] levels of a nominal 1.0 g/BHP-h, equal to the spark-ignited natural gas fueled engine, have been achieved for the gas-diesel and are described. In addition, the higher opacity exhaust plume characteristic of gas-diesel ...
Concentration of an amine solution for removal of hydrogen sulfides and carbon dioxide from natural gas, is tested by carbon dioxide absorption measurement in an apparatus allowing complete reaction to give reliable results.
The increasing price differential between natural gas and coal will create a demand for technology that can allow the displacement of natural gas with coal in power plants. Coal gasification is the standard approach suggested to allow coal to displace natural gas. However, the relatively high capital investment required for coal gasification will require fuel cost differentials higher than those anticipated in the near term before coal gasification replaces natural gas. One way of achieving shorter term displacement of natural gas by coal would be to develop technology that would allow coal to be used as the heat source for the endothermic reforming of natural gas. In a natural gas-fired combined cycle power plant, the endothermic heat of reforming, which would be provided by coal combustion, is recovered in the combined-cycle. Therefore, ...
At the St. Joe Minerals Corp.'s zinc smelter powerplant, an SO2 emission control program evolved into a cooperative program with the Bureau of Mines for installation and initial operation of a citrate process flue gas desulfurization demonstration plant. ...
The report describes a computer model developed by TVA to simulate the performance and determine the economics of coal cleaning, or coal cleaning combined with flue gas desulfurization (FGD), for power plant emission control processes over a wide range of user-specified condition...
The manual describes a combined coal-cleaning and flue gas desulfurization (FGD) computerized design and cost-estimate model and gives detailed procedures for using it. All inputs and outputs are described, as well as the various options available. Design and economic premises ar...
This project addresses the problem of flue gas desulfurization (FGD) sludge disposal to land. Specifically, the chemical species of FGD sludge constituents are thermodynamically modeled using the equilibrium constant approach, in an attempt to predict the constituent concentratio...
The report gives an initial assessment of the feasibility of disposing of flue gas desulfurization wastes in mines and in the ocean. The purpose of the assessment was to evaluate environmental, technical, regulatory, and economic aspects of the use of such disposal sites. Availab...
Crockford, G. W., Crowder, M., and Prestidge, S. P. (1972).Brit. J. industr. Med.,29, 378-386. A trace gas technique for measuring clothing microclimate...Full Text Available
In this paper we have proposed a novel gas turbine cycle with hydrogen-fueled chemical-looping combustion, and the system study on two hydrogen-fueled power plants, the new gas turbine cycle and an advanced gas turbine cycle with H{sub 2}/O{sub 2} combustion, has been investigated with the aid of exergy principle (EUD methodology). The hydrogen fueled chemical-looping combustion in the new gas turbine cycle consists of two successive reactions: hydrogen fuel is reacted with metal oxide (reduction of metal oxide), and then instead of air or pure oxygen, the reduced metal is successively oxidized by the saturated air. As a result, the new hydrogen-fueled gas turbine cycle has a breakthrough performance, with at least about 12 percentage-point higher efficiency compared to the gas turbine cycle with H{sub 2}/O{sub 2} combustion, and will be environmentally superior ...
Gas-fired combined cycle plant may be the norm when it comes to new plant but it comes in a variety of shapes and sizes. Samarinda uses aero-derivatives with the famous Rolls-Royce RB211 gas generator. (author)
The feasibility of producing a pocket-sized air contaminant monitor based upon a miniature gas chromatograph and an integrated microcomputer has been demonstrated and a practical design for the instrument is presented. This pocket-sized instrument is intended to be used as a pers...
Apparatus and method for selective measurement of tritium oxide in an environment which may include other radioactive components and gamma radiation, the measurement including the selective separation of tritium oxide from a sample gas through a membrane into a counting gas, the generation of electrical pulses individually representative by rise times of tritium oxide and other radioactivity in the counting gas, separation of the pulses by rise times, and counting of those pulses representative of tritium oxide. The invention further includes the separate measurement of any tritium in the sample gas by oxidizing the tritium to tritium oxide and carrying out a second separation and analysis procedure as described above.
A high-voltage cathode initiates an electron emission, resulting in a reduction in the carbon dioxide concentration in exhaust gas from the burning of hydrocarbon fuel. Assuming that the observed carbon dioxide reduction is originated from the molecular decomposition, the energy needed for the endothermic reaction of this carbon dioxide reduction may stem primarily from the internal energy reduction in the exhaust gas in accordance of the first law of the thermodynamics. An oxygen increase due to the reduction in carbon dioxide in a discharge gas was observed in real time.
This report consists of three sections. The first section is a brief general overview of all the issues that impact the competition between natural gas and electricity in industrial applications. The second section of this report focus on the all the marketing issues and provides detail analysis of the status of these issues in Europe, Japan and United States. The third section of this report is a detail review of the current status of the competition between gas technologies and electro-technologies, it also make recommendation for developing new gas technologies. The fourth section is a contribution from M. Pettersson and S. Stenstroem, Sweden, on infrared dryers. (authors)
Makeup water is distilled internally in an amine gas treating unit by adding it to the reclaimer used to process a slipstream of lean amine from the stripper.
Experimental data on the gas holdup and the mean bubble size in a bubble column with a single nozzle was obtained for gas-molten salt systems of a eutectic mixture of LiCl (58 mol %)-KCl (42 mol %) and molten NaNO/sub 3/. The liquid-phase mass transfer coefficient K /SUB L/ was evaluated from the specific surface area a and the volumetric coefficient K /SUB L/ a data for oxygen and carbon dioxide absorption into molten NaNO/sub 3/. The dimensionless correlations of the performance of bubble columns for aqueous solutions can be extended to the gas-molten salt systems.
This dissertation deals with membrane gas absorption in the application of CO{sub 2} removal by aqueous alkanolamines, using microporous PTFE hollow fiber membranes. A new lab-scale apparatus was constructed and an extensive experimental study executed to determine the performance of the membrane gas absorber, with aqueous solutions of monoethanolamine (MEA) and methyldiethanolamine (MDEA) as absorbents. The important operation parameters CO{sub 2} partial pressure, gas velocity, liquid velocity, temperature and liquid CO{sub 2} loading were systematically varied within the range typically experienced in a process for exhaust gas CO{sub 2}-removal
This thesis dealt with the metal-organic gas phase epitaxy with nitrogen as carrier gas. For this first by means of three-dimensional modelings of the epitaxy process the influence of the carrier gas on the processes was explained. The optimization of the growth parameter for the whole light-emitting-diode structure in double-hetero arrangement resulted that an a temperature of 770 C and a V/ III-ratio of 150 layers with a high crystal quality could be reached.
Access for independents to retail gas markets was a central concern in European policy reform efforts in the 1990s. Upstream oil and gas companies reacted with strategic intentions of forward integration. By late 2004, forward integration was still weak, however. An important explanation of the gap between announced strategic re-orientation and actual strategy implementation lies in the political failure of EU member states to dismantle market barriers to entry for independents. Variations between companies in downstream strategy implementation are explained by variations in business opportunities and internal company factors.
Kawasaki Heavy Industries, Ltd. has developed a gas turbine combined cycle and cogeneration plant computer aided engineering (CAE) system, which creates cycle heat balance automatically on given configurations of gas turbines, heat recovery boilers, steam turbines and auxiliaries. The system can predict the performance of the plant as a function of control set points, loads, process steam requirements and ambient conditions, which enables accurate and fast design of gas turbine combined cycle and cogeneration plants. (author)
Dimethyl methylphosphonate (DMMP), a chemical simulant of the nerve gas GB, was decontaminated with a nonthermal atmospheric pressure plasma. The decontamination efficiency was measured qualitatively by means of Fourier transform spectroscopy and quantitatively by means of gas chromatography. With helium gas only, 10g/m2 of DMMP on an aluminum surface was 99.9% decontaminated in 2min, furthermore, with the addition of 5% of oxygen gas, it was 99.99% decontaminated in 10min. Given the low input power (<100W) and temperature (<75degreeC), this plasma is eligible for nondestructive decontamination of almost all material surfaces.
The purpose of this work was to develop and evaluate a method of locating breached fuel within the Fast Flux Test Facility (FFTF) reactor based on the relative response of the delayed neutron monitors (DNM) located on each of the three primary sodium cooling loops. The primary method of location is the use of tag gas containing unique ratios of the noble gases xenon and krypton. Although the tag gas system works quite well, it is relatively expensive because of the costs of preparing and loading the gas into each fuel pin. Triangulation of DNM signals could potentially decrease tag gas costs while maintaining overall location reliability.
Biogas supply to the public gas grid is a new option discussed in the most recent publication of Fachagentur Nachwachsende Rohstoffe (FNR) e.V. The biogas is purified, upgraded to natural gas quality and fed into an existing gas grid. Once there, it can be transported across long distances and also used for electric power generation at the consumer side. The study investigates inhowfar and in what instances this method is feasible and promising. It discusses the technical background and the regional potential of biogas. Seven model biogas systems are presented as examples. (orig.)
This paper is a quarterly report describing the use of a new soil gas collection device which allows the collection of soil gas in the field for later analysis in the laboratory. It describes the installation of this sampling device and the procedure for setting the probe, extraction of soil gas beneath the surface, and sealing of the soil gas for transport. The sites used for initial testing was the top of Yucca Mountain and Crystal Spring in Ash Meadows National Wildlife Refuge. The results from this initial test showed no volatile matter present in the soil at these locations.
The multicell proportional chambers at the backing calorimeter of the ZEUS experiment at the storage ring HERA are supplied with a gas mixture of Ar/CO[sub 2] by an open gas system. Flow proportional counters with the build-up [sup 55]Fe sources are used as gas system monitoring detectors. The ZEUS experiment is planned to collect data for about 10 years. Therefore, the lifetime of the Ar/CO[sub 2] mixture should be known. In this paper, the results of laboratory tests and preliminary measurements of the aging effects for monitoring counters are presented. ((orig.))
The risk perception of the public consists of two components: the objectively factual component and the subjectively irrational component. The two strategies adopted by the German gas supply industry are the internal and the external communication strategy. Concepts and measures of accident precaution, registration and analysis of accident data (installation and operating errors, defects on flue systems, pipelines and valves, subsequent installation of gas appliances) are discussed. (R.P.)
The energy price volatility model suggests that some of the proposed natural gas programs can contribute to energy price stability. The sector most vulnerable to fuel price variations is, of course, the transportation sector. The most effective strategy to achieve energy pace stability is to reduce petroleum consumption in this sector. The natural gas vehicle program is therefore recommended as potentially important and worthy of further consideration. At this point, distinguishing the merits of various subprograms is not feasible. This result farther supports the conclusion that the DOE`s energy R&D portfolio is not efficiently balanced and an increase in oil and gas research should be a high priority. The DOE has responded favorably and has significantly increased its proposed research with the explicit objective of displacing oil in the transportation sector. The enhanced research and development program for energy ...
This paper gives a Coulomb gas representation for level kN = 1 supersymmetric SU(2) Kac-Moody algebra in terms of three free scalar superfields. It is clarified how this representation reduces to a Coulomb gas representation for the corresponding bosonic SU(2) Kac-Moody algebra and the free fermionic algebra. The primary superfields and the correlation functions, which satisfy the supersymmetric Knizhnik-Zamolodchikov equation, are also discussed.
The US$360 million project to increase gas supplies to Eastern and Southern Thailand is discussed, and the use of international competitive bidding to purchase the line pipe and other facilities is reported. The government approved proposal for a gas fired combined-cycle power station and gas separation plant are discussed. (UK).
The need is substantiated for using remote control of technological processes on blowout dangerous beds. A method is proposed for this control based on recording with the help of AGZ apparatus for gas release into the roadway. Distinguishing features are indicated for the change in methane concentration in the roadway with normal occurrence of the process and in the case of blowout of coal and gas.
Smart electricity and gas supply grids are a prerequiste for full-scale utilization of the potential of modern energy-saving appliances and equipment. Direct exchange of information between the supplier and the consumer is indispensable for reducing costly and energy-intensive peak loads. (orig.)
This project dealt with use of condensing heat exchangers to recover water vapor from flue gas at coal-fired power plants. Pilot-scale heat transfer tests were performed to determine the relationship between flue gas moisture concentration, heat exchanger design and operating conditions, and water vapor condensation rate. The tests also determined the extent to which the condensation processes for water and acid vapors in flue gas can be made to occur separately in different heat transfer sections. The results showed flue gas water vapor condensed in the low temperature region of the heat exchanger system, with water capture efficiencies depending strongly on flue gas moisture content, cooling water inlet temperature, heat exchanger design and flue gas and cooling water flow rates. Sulfuric acid vapor condensed in both the high temperature and low temperature ...
This invention pertains to a Fischer Tropsch process for converting synthesis gas to an oxygenated hydrocarbon with particular emphasis on dimethyl ether. Synthesis gas comprising carbon monoxide and hydrogen are converted to dimethyl ether by carrying out the reaction in the presence of an alkali metal-manganese-iron carbonyl cluster incorporated onto a zirconia-alumina support.
To suppress space charge blowup in an ion beam passing through a photoneutralizer, it is necessary to introduce some background gas. An analysis is presented of the neutralization of a high-energy, >200-keV negative deuterium ion beam, exposed to photodetachment while in the presence of deuterium. With a gas thickness of <0.01 Torr.cm, the neutral fraction in the output beam is found to be about the same as that gotten from the photoneutralizer operating in vacuum. Neutral atom beam injection for plasma heating is discussed.
This paper describes a practical knowledge on gas engine performance and combustion characteristics which are required by experimental studies for two types of developed gas burning engines, i. e. a spark ignited gas engine and a dual fuel engine, and also introduces their practical use and application. As for dual fuel engine performance, a manifold air pressure of about 27% was decreased, a scavenging ratio of 23% reduced and an exhaust temperature at the turbine inlet on 14% was increased at the gas engine operation under the mean effective cylinder pressure of 1.22 MPa in comparison with the diesel operation. Furthemore, empirical data on the effect of excess air ration on the engine performance and combustion characteristics, a risk of knocking during changing over on the dual fuel engine operation, and the rated output in case of using alternate fuel gas were reported. Two ...
Triassic sedimentary rocks are widespread in the Pechora sineclise and Pre-Uralian edge trough territory. They are up to 920 and 400 m thick respectively. Commercial flows of oil and gas have been obtained from these deposits in the last few years. The geology of the area is described and its is concluded that the main oil and gas potential should be connected with the northern areas of the Pechora sineclise.
I propose that an interpretation of the interaction of noble gas atoms with metal surfaces as predominantly physisorbing provides the best explanation for the systematics of their binding energies and surface dipoles, as well as for the tendency of noble gas atoms to bind in low coordinated sites. In the present context physisorption is defined as a process driven by the overlap of the electrostatic atomic potentials of the interacting species. (orig.)
The technical and economic feasibility of using a typical, elemental, phosphorus byproduct gas stream in methanol production is assessed. The purpose of the study is to explore the potential of a substitute for natural gas. The first part of the study establishes economic tradeoffs between several alternative methods of supplying the hydrogen which is needed in the methanol synthesis process to react with CO from the off gas. The preferred alternative is the Battelle Process, which uses natural gas in combination with the off gas in an economically sized methanol plant. The second part of the study presents a preliminary basic design of a plant to (1) clean and compress the off gas, (2) return recovered phosphorus to the phosphorus plant, and (3) produce methanol by the Battelle Process. Use of elemental phosphorus byproduct gas in methanol ...
This paper reports that Sen. Bennett Johnston (D-La.) has vowed if Congress enacts an omnibus energy bill in the fall, it will not include a restriction on states' rights to proration natural gas production. Johnston, Senate energy committee chairman, will lead Senate conferees in their negotiations with members of the House of Representatives. The House energy bill has an antiproration amendment. The Senate's bill does not. Oklahoma's and Texas' recent actions to proration gas production prompted the federal legislation.
The 66 fields discovered since the 1960s in the northern West Siberian basin contain at least 22 trillion m/sup 3/ (777 tcf) of proved gas, almost one-third of the world's reserves. Half of these fields are giants (> 85 billion m/sup 3/ or 3000 bcf of reserves). These include the largest and second-largest gas fields in the world-Urengoy (8.099 trillion m/sup 3/ or 286 tcf of gas) and Yamburg (4.81 trillion m/sup 3/ or 170 tcf of gas)-as well as most of the other ten largest gas fields in the world. The West Siberian basin occupies a 3.4-million km/sup 2/ (1.31-million mi/sup 2/) arctic lowland immediately east of the Ural Mountains, extending north under the Kara Sea. It is a composite basin, with Mesozoic-Cenozoic basin fill on top of a Paleozoic basin that overlies a crystalline Archean-Proterozoic framework. The productive zones in the northern basin are principally ...
Cattle or chicken manure is pelletized, and a bed of the pellets is combusted at the bottom to create a temperature gradient and to generate a fuel gas. Thus, an approximately 25 cm-high bed of approximately 5 mm-diameter chicken manure pellets was combusted to produce a fuel gas of 1622 kcal/kg manure.
There are several concerns which bring to consider natural gas as a viable alternative to liquid fuels in transport. First, natural gas allows the curbing of global pollution in this steadily growing industry. Indeed, decoupling greenhouse gas emissions from transport growth has become a major issue in tackling climate change. Second, a more extensive use of natural gas would relieve city air quality, which is presently at levels harmful of human health. Nonetheless, this is just one side of the coin. The other side entails building a refuelling station network, and this carries financial requirements. The financing fraction holds a pivotal role in deciding whether natural gas for automotive purposes is an efficient solution. The final aim of this work is, therefore, to compare the natural gas advantages, stemming from avoided global and local emission, with the ...
In order to facilitate observations of low energy nuclear reactions, a new type recoil mass-separator together with a new gas-jet target system is being developed at the tandem accelerator facility in Kyushu University. The expected mass-resolving power of the separator is 220 for a solid angle of 10 msr and the practical thickness of the gas-jet target will exceed 0.1 atm#centre dot#cm for the light elements of H and He. (author).
The EPA proposed effluent limitations guidelines and standards for the offshore segment of the oil and gas industry on August 26, 1985. On November 26, 1990, and March 13, 1991, the Agency reproposed effluent limitations guidelines and standards for both drilling and production wastes. The report is primarily concerned with the total annualized cost incurred by the offshore oil and gas industry in complying with the regulations.
In a suicide committed using aluminium phosphide (AlP) the liberated toxic phosphine gas was detected in post-mortem specimens using a headspace gas chromatographic procedure with a nitrogen-phosphorous detector (HS-GC/NPD). At autopsy a direct sampling into airtight headspace vials for a later analysis is recommended. AlP has to be considered a potent pesticide and its use and availability should be restricted as much as possible.
Turkey's natural gas (NG) production is very small and is almost all imported. Turkish natural gas production in 2000, 23 billion cubic feet (Bcf), met around 4% of domestic natural gas consumption requirements. NG consumption is estimated at around 700 Bcf in year 2002, accounting for around 17% of Turkey's total energy consumption. Turkish natural gas demand had been projected to increase extremely rapidly in coming years. Country oil production is 50,674 barrels per day (bbl/d) of which 46,674 bbl/d was crude oil in 2002. In 2002, oil consumption was 635,000 bbl/d and net oil imports was 584,326 bbl/d in Turkey. Oil provides around 43% of Turkey's total energy requirements. (Author)
This article describes how a natural gas-fired combined cycle with increased firing temperature, reduced cooling air usage, improved component efficiencies, and cycle enhancements could achieve a lower heating value plant efficiency of greater than 60%. Today's gas turbine systems feature high fuel-to-electricity efficiencies. Efficiencies, on a lower-heating-value (LHV) basis, for large natural gas-fired combined-cycle systems for the utility market have been demonstrated at 54%. Even though manufacturers will make improvements in the 1990s, efficiency levels will reach a plateau. Cycle innovations and gas turbine design changes will achieve LHV efficiencies in the 60% range for natural gas-fired utility machines.
A new process for the removal of tar from biosyngas, OLGA (Oil and Gas Washer), is presented. This gas cleaning technology is based on physical principles and is designed to eliminate tar problems that relate to fouling and er pollution. The applied principles are confirmed by experimental validation. OLGA can be operated without suffering from harmful effects on important gasification characteristics as cold gas efficiency, gasifier simplicity, and feedstock flexibility. Some fundamental considerations in the development of OLGA are discussed. Amongst these is a different approach to the tar problem. This approach does not consider the total tar content as decisive in the evaluation of gas cleaning equipment. Instead, evaluation is focussed on whether tar properties as condensation behaviour and water solubility can still occur. A biosyngas free of tar should therefore be synonymous to a biosyngas that ...
Gas separation membranes with polydimethylsiloxane(PDMS)/polystyrene(PS) were prepared by using the sequential interpenetrating polymer network (IPN) method with various PS contents (10?70wt%). These gas separation membranes can be applied to reduce the smoke density in the emission gas of diesel engines. PS content has a pronounced effect on the membrane performance. It was found that the optimized PS contents in the final membrane were 50wt%. The emission capacities of diesel engines used in this study were 632 cc and 11,149 cc. When the oxygen separation membrane was used in the diesel engines, the smoke density of both diesel engines was remarkably reduced (35?73%). The oxygen concentration in the inlet air affects the composition of the emission gases. Especially, hydrocarbon (HC) dec...
Thailand's demand for gas will outstrip supplies in the late 1990s as rapid economic growth continues. Gas will be a cornerstone for Thai energy policy throughout the growth, although sources in neighboring countries need development. Thai gas production will rise 25% from 1992 to average 1 bcfd by 1995. Including production from new discoveries, production could rise to 1.5 bcfd by 2000, up almost 90% from the 1992 level. Increased gas flow output in the mid-1990s will be due largely to development of Gulf of Thailand fields. By 1998, production from Gulf of Thailand fields will not be enough to offset the decline in today's fields. Thailand will need to import more than 1 bcfd by 2005 in the absence of future discoveries in the country. The paper discusses new pipelines and imports.
The ElectroStatic Precipitator (ESP) removes dust and tar droplets very efficiently from biomass product gas. Dust was removed for more than 99%. The tar dewpoint was reduced from 130C to 21C, which is sufficient for the application of the product gas in a gas engine. Tar removal is not sensitive to the voltage or fluctuations in the gas residence time . The voltage was varied between 28 to 37 kV{sub arith} and the gas residence time between 4 and 11s. Fouling of the ESP collector plates was negligible, which was concluded from visual inspection after 200 hours of operation. A reduction in the residence time reduces the size of the ESP and has a significant impact on the investment costs of the ESP. Keywords: electrostatic filter, tar removal, circulating fluidised bed (CFB)
The authors report the fabrication and characterization of a low temperature (200--400 C) thin film gas sensor constructed from a MOCVD-grown yttria-stabilized zirconia (YSZ) layer sandwiched between two platinum thin film electrodes. A reproducible gas-sensing response is produced by applying a cyclic voltage which generates voltammograms with gas-specific current peaks and shapes. Growth conditions are optimized for preparing YSZ films having dense microstructures, low leakage currents, and maximum ion conductivities. In particular, the effect of growth temperature on film morphology and texture is discussed and related to the electrical and gas-sensing properties of the thin film sensor device.
In this paper, the authors investigate the technical and economical aspects of the natural gas injection in non-integrated pig-iron plants using charcoal in the blast furnace. The effects of the natural gas injection concerning the blast furnace flame temperature, charcoal consumption, productively and permeability are analyzed. It was found that the injection is beneficial in many ways, such as in the improvement of the productivity and quality, if the flame temperature is kept within an appropriate range. In the financial-economic project`s evaluation, the cash flow for the natural gas injection was analysed considering two blast conditions: through the drying and oxygen enrichment of the air. A sensibility analysis is presented in which the internal rate of return of the investment varies according to the prices of charcoal and oxygen. 3 refs., 3 figs., 3 tabs
The majority of Brazilian big cities served by conventional railroad systems with routes starting in the center of the URBIS, destinate them the long distances transport of passengers and cargo. Actually, these systems are being transformed to become commuter trains which join a great capacity of transportation to a much lower costs of implantation than subway ones. The most important characteristic of this train, when talking about energy consumption, is the possibility of using different kinds of explosion engines from three cycles: Diesel, mixed (Diesel + Natural Gas), and Otto moved by natural gas, besides the traditional electric traction. The use of natural gas in Otto cycle engines shows itself competitive from the point of view of investments, operational costs and environmental preservation. (author). 10 refs., 1 fig
Lean premixed combustion (LPC) of natural gas is of considerable interest in land-based gas turbines for power generation. However, modeling such combustors and adequately addressing the concerns of LPC, which include emissions of nitrogen oxides, carbon monoxide and unburned hydrocarbons, remains a significant challenge. In this paper, characteristics of published simulations of gas turbine combustion are summarised and methods of modeling turbulent combustion are reviewed. The velocity-composition PDF method is selected for implementation in a new comprehensive model that uses an unstructured-grid flow solver. Reduced mechanisms for methane combustion are evaluated in a partially stirred reactor model. Comprehensive model predictions of swirl-stabilised LPC of natural gas are compared with detailed measurements obtained in a laboratory-scale combustor. The model is also applied to industrial combustor ...
Remote, offshore gas reserves have long been a challenging deepwater petroleum resource to tap. Natural gas in many offshore regions is plentiful, but lacks access to the market because of the logistical challenges and costs. Most large offshore gas discoveries are capped, and gas associated with oil production is re-injected into the reservoir or is flared. A more attractive option is to convert the gas into a liquid product on a floating production, storage, and offloading (FPSO) vessel. However, some conventional process technologies are not well suited for operation on floating vessels that are highly space and weight constrained and may challenge vessel stability during inclement weather. Microchannel process technology units under development offer intensified processes that are suit...
In this paper it will be discussed how to most effectively give room to competitive forces in natural gas markets, given the traditional merchant pipeline as point of departure. Alternative models of organizing the market will be reviewed: we first consider decreasing barriers to entry and then analyse advantages and drawbacks of a third party access system. In this context different forms of implementing a competitive market for transportation capacity and coordinating it with gas trade are discussed, among them a simultaneous auction of gas and transmission capacity. Finally a hub system of point markets will be suggested to improve the currently implemented third party access system and to allow for competitive markets for gas and transportation service. 33 refs., 6 figs.
The Gas Research Institute established the Gas Appliance Technology Center (GATC) in 1982 to develop improved gas appliances. Between 1986 and 1992, the scope of GATC activities at Battelle included technology transfer and overall industry support, residential appliances, commercial appliances, and residential space conditioning. The following tasks are representative of the GATC activities described in the report; gas burner technology, appliance venting, emissions, water heating, range/oven technology, self-powered appliances, commercial cooktop burners, reconstituting ovens, appliance reliability improvement, combination space-heating/water-heating systems, condensing heat exchangers, corrosion testing, and space heating technology. The report includes references to available sources for further reading.
One of the unsolved problems of the natural gas dual fuel engine is that there is too much exhaust of Total Hydrogen Carbon(THC) at a low equivalent mixture ratio. To fix it, a natural gas mixed with hydrogen was applied to engine test. The results showed that the higher the mixture ratio of hydrogen to natural gas, the higher the combustion efficiency. And when the amount of the intake air is reached to 90% of WOT, the combustion efficiency was promoted. But, like a case making the injection timing earlier, the equivalent mixture ratio for the nocking limit decreases and the produce of NOx increases. 5 refs., 9 figs., 1 tab.
AISI 5140 steel was plasma nitrided at various gas mixtures of nitrogen, hydrogen, and argon to investigate the actions of hydrogen and argon on plasma nitriding. The structural and mechanical properties of ion-nitrided AISI 5140 steel have been assessed by evaluating composition of phases, surface hardness, compound layer thickness, and case depth by using X-ray diffraction (XRD), microhardness tests, and scanning electron microscopy (SEM). It was found that the growth of compound layer can be controlled and the diffusion improved when the gas mixture includes H_2 gas. Additionally, it was determined that the amount of Ar in dual gas mixture must be at 20% minimum to obtain distinctive surface hardness and compound layer thickness.
Laboratory tests have been done to assess the feasibility of using microwaves to manufacture refractory liner boards as used in the steel industry. Results show that microwaves cured and dried the product about ten times faster than the conventional gas-oven process. The quality of boards dried with microwaves appears to be as good or better than of those dried with gas. The potential for fast, energy-optimized drying in a small space has been demonstrated. Economically, the energy-cost of using microwaves is comparable to using gas when drying the last 30% moisture content, that is, for about the last 50% of the present gas-drying time. For higher moisture contents, such as encountered in the early stages of drying, the energy can be supplied at a lower cost by gas. 8 figs.
In energy industries, it is always of difficulty to produce high heat value(HHV) gas continuously using pulverized coal. In this paper, a new type furnace for partitioned alternative gasification using pulverized coal is developed, in which the oxidation and reduction reaction occur alternatively with the dropping of pulverized coal and finally HHV gas could be continuously obtained at the reduction zone exit and low heat value(LHV) gas at the oxidation zone exit. Furthermore, the gasification characteristics and their factors in furnace are numerically simulated under two dimensional model with a self-coded program, based on heat, mass and energy transfer as well as reaction principles. It is found that the producing rate of HHV gas is 1.10Nm3/kg with heat value of 11.72MJ/Nm3, however, t...
Various theories and examples of modelling, forecasting and optimization designing in the different parts of the petroleum and gas industries are presented, stochastic programming for long term planning in the refining industry, stochastic model for gasoline blending, feedstock optimization, location and sizing for offshore platforms, hydrocarbon exploration simulation rapid method, valuation of oil field development leases, economic models for petroleum allocation, models for oil supply market, trade embargo game theory, stochastic programming of gas contract portfolio management, scheduling transportation of oil and gas, strategic planning in an oil pipeline company, simulation of offshore oil terminal systems, hierarchical selection of oil and gas distribution systems.
The method is related to hydrodynamic methods for studying wells and may be used in the prospecting and mapping of gas and gas condensate deposits and formations. The method consits of drilling exploratory wells and measurement of the physical parameters of the stratum liquid. The piezometric levels are periodically determined simultaneously in all the observation wells during a change in the atmospheric pressure, and the presence of a remoteness of the gas deposit from the well is judged from the size of the increments in the piezometric levels intime. The determinations of the piezometric levels in the wells are conducted during an abrupt change in atmospheric pressure, for instance, during the replacement of a cyclone by an anticyclone or the reverse. The atmospheric pressure is measured by a barograph, while the piezometric levels are measured by high precision level meters or pressure gauges of low pressure. The method ...
The purpose of this project was to build a long-range, parallel hybrid gas/electric vehicle capable of driving beyond the communter capabilities of series hybrid vehicles. It was envisioned that since the gas engine would be able to independently propel the car when needed and that the electric motor would be capable of doing the same, then you have a very desirable situation where this car can operate much more cheaply on electricity for the short distance runs under approximately 60 miles and also be able to propel the vehicle via the gas engine on the long-distance trips. During the time the car would be operating in the gas engine mode, it would be also recharging the 16 deep cycle batteries via the electric motor now being used as a generator. Then, even on long-distance trips, the electric motor could be used, after having been fully or partially recharged, to even further reduce cost per mile.
Ordos Basin, the second largest sedimentary basin in China, contains enormous natural gas resources. Each of the four giant gas fields discovered so far in this basin (i.e., Sulige, Yulin, Wushenqi and Jingbian) has over 100 billion cubic meters (bcm) or 3.53 trillion cubic feet (tcf) of proven gas reserves. This study examines the stable carbon isotope data of 125 gas samples collected from the four giant gas fields in the Ordos Basin. Source rocks in the Upper Paleozoic coal measures are suggested by the generally high {delta}{sup 13}C values of C{sub 2}-C{sub 4} gaseous hydrocarbons in the gases from the Sulige, Yulin and Wushenqi gas fields. The {delta}{sup 13}C values of methane, benzene and toluene in gases from the Lower Paleozoic reservoirs of the Jingbian field indicate a significant contribution from humic source rocks, as they are similar to those in ...
The productivity characteristics of perforated gas well are investigated for the first time under real conditions considering drilling damage, perforation compacted zone and anisotropy in this paper. A non-linear finite element model for non-Darcy flow in perforated gas reservoir is built to consider the effects of twelve factors on productivity ratio (PR) of perforated gas well. The nomographs for two cases are presented in this paper. Compared with previous works, the following results are found: (1) the effects of drilling damage and perforation diameter on PR of gas well are more remarkable than that in oil well; (2) any perforation phase may be the best or the worst as to perforating gas well, which depends on anisotropy, drawdown and that whether or not perforations are beyond drilling damage zone; (3) the increase in perforation length hardly improve PR of ...
Puffer gas circuit breaker used widely in interrupters with from middle capacity to large capacity does not keep away from reacting force of the puffer with high functions in principle and there is a limit in low operation. In this study, aiming at low operation of the interrupters, in order to clarify the basic motions of hybrid circuit interrupter that is the combination of thermal puffer gas circuit breaker and vacuum circuit breaker, the interrupting ability of simple thermal puffer gas breaker and the voltage sharing characteristics in the cases of series connection with the vacuum circuit breaker are studied. The results of the study are as follows. In comparing terminal short circuit accident interrupting ability of single flow typed thermal puffer gas breaker with that of double flow typed thermal puffer gas breaker, the interrupting ability of the double flow typed thermal ...
Electricity generation from natural gas in gas turbine units can be made substantially more efficient by preliminary methane conversion to a synthesis gas containing hydrogen and carbon monoxide and/or by the use of some of the synthesis gas produced in industry. An alternative improvement involves the introduction of solid oxide fuel cells (SOFCs) and the use of the synthesis gas in them. In this study, a modified scheme of gas turbine cycle that includes an SOFC, a membrane reactor (instead of a traditional combustion chamber), and a catalytic reactor to perform methane conversion to produce hydrogen (synthesis gas) is proposed. Variations of the energy and exergy efficiencies of the integrated system with operating conditions are provided, showing, for example, that SOFC efficiency is enhanced if the fuel cell active area is augmented. ...
A gas injection diesel engine was developed as an approaching measure to the diversification of fuel. Contrary to the usual low pressure gas application engine, this engine applies a so-called diffuse combustion method, in which high pressure (24.7Mpa) gas fuel is injected directly in the cylinder and is ignited and combusted by a little pilot fuel injected almost at the same time. The engine have following features. As a principle, it can attain the same heat efficiency and output rate as a diesel engine in any load range. It is excellent in responsibility to load fluctuation. There is no internal leakage of gas fuel to the scavenging chamber (the crank chamber) in the compression stroke. Not only a wide range of mixed combustion of gas fuel and heavy oil fuel, but also single combustion of heavy oil is possible. It is, therefore, drawing attention as an engine for an LNG ship and ...
The following industrial-scale power station processes are compared with natural gas/light fuel oil heating: Conventional steam generation, steam generation with gas turbine upstream, gas turbine process with low-pressure-waste heat boiler and cogeneration. Industrial gas turbines between 10 and 25 MW are compared with one another; typical boilers and industrial turbines are described. CO{sub 2} and NO{sub x} emissions are indicated. The steam turbines used are the efficient and robust turbines used in industry, wherever possible they are built as single-line plant with the gas turbine. (orig.) [Deutsch] Es werden folgende Industriekraftwerksprozesse mit Erdgas-Leichtoelfeuerung verglichen: Konventioneller Dampfprozess, Dampfprozess mit Vorschaltgasturbine, Gasturbinenprozess mit ND-Abhitzekessel und Kombianlage. Die Industriegasturbinen zwischen 10 und 25 MW werden ...
This conference was attended by decision makers throughout the supply chain in the natural gas industry who face the continuing challenges of changes in market mechanisms, pricing options, and transmission alternatives. It provided an opportunity to review issues affecting producers, shippers, marketers, and end-users in an environment of tight energy markets and high, inelastic demand. The constraints on adequate energy supplies are influenced by economic factors, current and future resources, materials, equipment, skilled labour, technology and financial capital. The 8 sessions of the conference dealt with the tight North American gas supply; the slow development of new supplies; resource access issues, including politics and supply security; the geopolitics of natural gas; impacts of high prices on the North American economy; energy industry impacts of high natural gas prices; domestic politics and ...
In order to establish the optimum fueling in a natural gas fueled dual fuel engine, tests were made for some operational parameters and their combination on the engine performances and the exhaust emissions. The results show that the gas oil quantity should be increased and gas oil injection timing should be advanced to suppress unburned hydrocarbon emission at middle and low output range, while the quantity should be reduced and the timing should be retarded to avoid onset of knock at high loads. The unburned hydrocarbon emission and the thermal efficiency are improved at the same load avoiding too lean natural gas premixture by restriction of intake charge air. However the improvement is limited because the ignition and initial combustion of pilot diesel fuel is deteriorated when the cylinder pressure is excessively lowered by throttling. The increase in pilot gas oil amount is ...
This dissertation concerns a study of the utilization of sorghum biomass as the fuel for a methane production system. The objective of this research is to determine an optimal sorghum-methane production system based on anaerobic batch digestion technology. The system is described as the interaction of three components: estimation of available biomass, storage of biomass, and the gas production. Levelized costs are obtained for each component. The biomass supply is assumed to decay exponentially in quality with storage time. The gas production process is a batch type of digestion with an exponential production rate. Gas production is formulated for a fixed planning horizon (one year) as a function of the number of batches and the batch residence times. The cost equation is then described as a function of these gas production equations and their levelized costs. The structure of this resulting equation is ...
The energy recovery scheme at Mucking Marshes landfill site, operated by Cory Environmental Limited, has been in operation since October 1991. Using landfill gas abstracted from the site, a gas turbine generates up to 3.2 MW net electric power for export. Operation and performance of the scheme has been monitored over the period January 1995 to August 1996. Overall performance since the first use of the turbine has also been studied, and has shown reliable and profitable operation. The capital cost of the gas turbine and gas compressor plant was approximately 1.8 million. Actual gas collection wells, pipework, pumping and monitoring facilities, while essential to the scheme, are considered part of the gas control equipment needed for the landfill site. Based on a notional electricity selling price of 4p/kWh, the current annual income from exported power is ...
In response to the Clean Coal II solicitation, Bethlehem Steel Corporation (BSC) submitted a proposal to the DOE in May 1988. The proposal submitted by BSC describes a Unique integration of commercial technologies developed by Davy/Still Otto to clean coke oven gas being produced at its Sparrows Point, Maryland steel plant. This innovative coke oven gas cleaning system combines secondary gas cooling with hydrogen sulfide and ammonia removal, hydrogen sulfide and ammonia recovery, ammonia destruction and sulfur recovery to produce a cleaner fuel gas for plant use. The primary environmental benefit associated with employing this innovative coke oven gas cleaning system is realized when the fuel gas is burned within the steel plant. Emissions of sulfur dioxide are reduced by more than 60 percent. The removal, recovery and destruction of ammonia eliminates the ...
This study develops a statistical model of industrial US natural gas consumption based upon historical data for the 1958-2003 period. The model specifically addresses interfuel substitution possibilities and changes in the industrial economic base. Using a relatively simple approach, the framework can be simulated repeatedly with little effort over a range of different conditions. It may also provide a valuable input into larger modeling exercises where an organization wants to determine long-run natural gas prices based upon supply and demand conditions. Projections based upon this demand framework indicate that industrial natural gas consumption may grow more slowly over the next 20 yr than being projected by the U.S. Energy Information Administration (EIA). This conclusion is based upon the assumption that natural gas prices will follow oil prices, as they have done over recent decades. If natural ...
As its indigenous gas supplies decline, the UK will need to import more gas. In November 2006, the Department of Trade and Industry issued a consultation on revising the consent regime for offshore gas storage and offshore liquefied natural gas unloading. A total of 27 responses had been received by the closing date of 16 February 2007 from a variety of interest parties including developers and their representative organisations, consultants, environmental organisations, maritime organisations, heritage organisations and other public bodies. This report presents the Government's response to the views expressed by these respondents. The majority of respondents supported the Government's proposals to put in place new legislation to permit offshore gas storage activities. Many believed new legislation was necessary to provide the legal certainty necessary ro encourage ...
The usually low wear resistance of titanium materials can be increased by the thermochemical surface treatment nitriding. In result of comparative investigations of gas and plasma nitriding it will be shown that it is possible to obtain a specific variation of the properties in the highly stressed case by means of these both technologies on example of the ({alpha}+{beta}) alloy Ti-6Al-4V. Gas and plasma nitriding was carried out in the temperature range from 650 to 800 C over 4 to 48 h in different gas atmospheres, i.e. 100% NH{sub 3} (gas), 100% N{sub 2} (gas and plasma), 20% H{sub 2} + 80% N{sub 2} and 20% Ar + 20% H{sub 2} (plasma). The temperature range was fixed in the middle of ({alpha}+{beta}) region, because the core properties are influenced negative in the field of {beta}-transustemperature. The relations between the applied nitriding technologies, the layer structure ...
In our previous work, we demonstrated that biomass-generated producer gas can be converted to ethanol and acetic acid using a microbial catalyst Clostridium carboxidivorans P7{sup T}. Results showed that the producer gas (1) induced cell dormancy, (2) inhibited H{sub 2} consumption, and (3) affected the acetic acid/ethanol product distribution. Results of this work showed that tars were the likely cause of cell dormancy and product redistribution and that the addition of a 0.025{mu}m filter in the gas cleanup negated the effects of tars. C. carboxidivorans P7{sup T} can adapt to the tars (i.e. grow) only after prolonged exposure. Nitric oxide, present in the producer gas at 150ppm, is an inhibitor of the hydrogenase enzyme involved in H{sub 2} consumption. We conclude that significant conditioning of the producer gas will be required for the successful coupling of biomass-generated ...
Gas Distribution Companies have long paid great attention to improving the quality of gas supply service to the consumer. This has involved them in an on-going attempt to successfully define and establish a clear computer assisted replacement programme which, when drawn up on a reliability basis, may also prove cost effective. The reasons which drive any gas line replacement programme are mainly related to the necessity: to improve the gas network asset so as to face a striking expected growth in gas demand; to refurbish old distribution systems with the purpose not only to increase the reliability and continuity of gas supply but also to reduce the rate of maintenance costs due to frequent repair works; to prevent the possibility of massive replacement works for a progressing ageing of the network. This paper will present the computer assisted procedure being ...
High and volatile natural gas prices have increasingly led to calls for investments in renewable energy. One line of argument is that deployment of these resources may lead to reductions in the demand for and price of natural gas. Many recent US-based modeling studies have demonstrated that this effect could provide significant consumer savings. In this article we evaluate these studies, and benchmark their findings against economic theory, other modeling results, and a limited empirical literature. We find that many uncertainties remain regarding the absolute magnitude of this effect, and that the reduction in natural gas prices may not represent an increase in aggregate economic wealth. Nonetheless, we conclude that many of the studies of the impact of renewable energy on natural gas prices appear to have represented this effect within reason, given current knowledge. These studies specifically ...
High and volatile natural gas prices have increasingly led to calls for investments in renewable energy. One line of argument is that deployment of these resources may lead to reductions in the demand for and price of natural gas. Many recent US-based modeling studies have demonstrated that this effect could provide significant consumer savings. In this article we evaluate these studies, and benchmark their findings against economic theory, other modeling results, and a limited empirical literature. We find that many uncertainties remain regarding the absolute magnitude of this effect, and that the reduction in natural gas prices may not represent an increase in aggregate economic wealth. Nonetheless, we conclude that many of the studies of the impact of renewable energy on natural gas prices appear to have represented this effect within reason, given current knowledge. These studies specifically ...
This contribution presents different approaches for the modeling of gas entrainment under water by a plunging jet. Since the generation of bubbles happens on a scale which is smaller than the bubbles, this process cannot be resolved in meso-scale simulations, which include the full length of the jet and its environment. This is why the gas entrainment has to be modeled in meso-scale simulations. In the frame of a Euler-Euler simulation, the local morphology of the phases has to be considered in the drag model. For example, the gas is a continuous phase above the water level but bubbly below the water level. Various drag models are tested and their influence on the gas void fraction below the water level is discussed. The algebraic interface area density (AIAD) model applies a drag coefficient for bubbles and a different drag coefficient for the free surface. If the AIAD model is used for the simulation ...
The overall goal of the Gas-to-Liquids Program at the U.S. Department of Energy`s Pittsburgh Energy Technology Center (PETC) is to develop technologies for the production of hydrocarbon fuels and premium chemicals from light alkane gases. PETC`s current Gas-to-Liquids Program comprises the development of four primary advanced conversion technologies, namely, partial oxidation, oxidative coupling, oxyhydrochlorination, and novel conversion processes. Based on the current state of development, it can be concluded that, in the near future, one or more of these technologies will reach proof-of-concept demonstration. Oxyhydrochlorination is the most advanced direct conversion technology, and the synthesis of lower cost methyl chloride from natural gas would impact several commercial technologies that utilize methyl chloride as an intermediate to high value products. Technology development for the partial oxidation of methane to ...
Rice plants at different seed-developing stages were exposed to HTO vapor in an exposure box for 1 h during daytime and nighttime to investigate the levels of tissue free water {sup 3}H (TFWT) and organically bound {sup 3}H (OBT) in different plant parts. In the daytime experiment, TFWT concentrations in leaves at the end of exposure (h{sub 0}) were around 100% of the 1 hour mean HTO concentrations in air moisture whereas in the nighttime experiment, they were as low as 30{approx}40% of the air concentration. TFWT concentrations in both experiments decreased very rapidly in the beginning but much more slowly later and those at harvest were hundreds to hundred thousands times lower than those at h{sub 0}. OBT concentrations varied with time in different manners depending on plant parts and exposure times and differed between at h{sub 0} and at harvest by factors of less than 10 on the whole. Even during nighttime exposures, OBT was produced at about a third the rate ...
An interest in electronic materials has led me to investigate new synthetic approaches to III-V' type semiconducting (13-15, current IUPAC designation for B and N groups in the Periodic Table) and magnetic (3-15) compounds. It is now possible to prepare binary (GaAs and GdP) and ternary mixed-metal (Al[sub x]Ga[sub 1-x]As) and mixed-pnictide (GaP[sub x]As[sub 1-x]) compounds in seconds from rapid, low-temperature-initiated metathesis reactions between a metal (III) trihalide and a trisodium pnictide, exemplified by MX[sub 3] + Na[sub 3]Pn [yields] MPn + 3 NaX, where M is Al, Ga, In, (Al,Ga), or a lanthanide; X is F, Cl, or I; and Pn is P, As, Sb, or (P,As). The precursors are mixed together in a dry box and ignited by light grinding with a mortar and pestle, or by brief, local heating from a hot filament. These reactions are very exothermic (calculated [Delta]H[sub rxn] (GaAs) = 138 kcal/mol) and typically reach temperatures in excess of 700[degrees]C ...
Smugglers, who make use of the Ukraine-Slovak border for their business, might be satisfied after last week. The Slovak government ordered the switching off of scanning equipment monitoring the movement of goods by train through the Matovce border line. The modern equipment was substituted by people, who aren't able to check freight cars as effectively as gadgets. Not only in Ukraine are they celebrating this success in corruption, who demanded the shut-off of the scanning equipment The bosses on the Slovak side are also rubbing their hands. As told to TREND by Margareta Grecova, spokeswoman for Cargo Slovakia, 90% of goods that cross through the border at Matovce are unloaded. The most frequently transported commodities are ore, coal, chemical and petroleum products. Smugglers put their consignments among iron ore and coal. They prefer goods with high consumer taxes. Besides alcohol, there are mainly cigarettes. These are put into boxes which are concealed in ...
Since the 1970 innovations have allowed both active and passive neutron techniques to address various safeguards and waste measurement needs in the DOE complex. Much research was focused on satisfjring the 100-nCi/g detection limit for TRU waste in 208-liter drums. The emphasis on measuring drum-sized containers for disposal at WIPP has resulted in improved waste assay capability that now needs to be extended to larger containers. The desire to expedite the decontamination and decommissioning of certtain DOE facilities, and the large waste encountered in that process, has prompted the need for increasingly large disposal containers. Instruments have recently been built to accommodate crates that are nearly 100 cubic feet in volume, such as a B-25 box or Standard Waste 13ox. The density of hydrogen inside a waste container profoundly affects the accuracy of neutron measurements, and the metal content greatly affects sensitivity. Depending on the matrix, and ...
The main objective of the present thesis was develop and get operational a real-time neutron radiography system, at the IPEN-CNEN/SP. This system is installed inside the shielding of an old facility, designed in 1988, for film radiography, which is installed at the beam-hole 08 of the 5 MW, IEA-R1 Nuclear Research Reactor. The most important modifications at the such facility were the increase of the {gamma}-radiation filter thickness, increase of the inner area of the shielding, design of a neutron collimator and a light tight box. The main characteristics of the neutron beam at the irradiation position are: flux: 1 x 10{sup 6}n/cm{sup 2}s, collimation ratio 70, effective energy 7 meV, diameter 20 cm, neutron/{gamma} ratio {approx} 10{sup 6}n/cm{sup 2}mrem. The real-time images have been obtained by means of an imaging system that consists of a screen scintillator, a light intensifier, a video camera, a digitizing frame grabber and a computer. The device composed ...
The main objective of the present thesis was develop and get operational a real-time neutron radiography system, at the IPEN-CNEN/SP. This system is installed inside the shielding of an old facility, designed in 1988, for film radiography, which is installed at the beam-hole 08 of the 5 MW, IEA-R1 Nuclear Research Reactor. The most important modifications at the such facility were the increase of the #gamma#-radiation filter thickness, increase of the inner area of the shielding, design of a neutron collimator and a light tight box. The main characteristics of the neutron beam at the irradiation position are: flux: 1 x 10"6n/cm"2s, collimation ratio 70, effective energy 7 meV, diameter 20 cm, neutron/#gamma# ratio #approx# 10"6n/cm"2mrem. The real-time images have been obtained by means of an imaging system that consists of a screen scintillator, a light intensifier, a video camera, a digitizing frame grabber and a computer. The device composed by the scintillator ...
A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of "2"3"7Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry. "2"3"8U can interfere with "2"3"9Pu measurement by ICP-MS as "2"3"8UH"+ mass overlap and "2"3"7Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and alpha spectrometry so that long and short-lived Pu isotopes ...
A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of {sup 237}Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry; a hybrid approach. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and alpha spectrometry so ...
The process of carbonate dissolution at the sediment-water interface has two possible end-member boundary conditions. Either the carbonate particles dissolve mostly before they are incorporated into the sediment by bioturbation (interface dissolution), or the vertical mixing is rapid relative to their extermination rate (homogeneous dissolution). In this study, a detailed radiocarbon profile was determined in deep equatorial Pacific sediment that receives a high rate of carbonate supply. In addition, a box model of sediment mixing was used to simulate radiocarbon, carbonate content, and excess thorium profiles that result from either boundary process following a dissolution increase. Results from homogeneous dissolution imply a strong, very recent erosional event, while interface dissolution suggests that moderately increased dissolution began about 10,000 years ago. In order to achieve the observed mixed layer radiocarbon age, increased homogeneous dissolution ...
The nuclear activity was conducted for many years in Romania under Traditional Safeguards (TS) and has developed in good conditions the specific nuclear safeguards. Now there is a good opportunity to improve the performance and quality of the safeguards activity and at the same time to increase the accountancy and control of nuclear materials by passing to Integrated Safeguards (IS) implementation. The legal framework is the Law 100/2000 for ratification of the Protocol between Romania and International Atomic Energy Agency (IAEA), additional completion to the Agreement between the Socialist Republic of Romania Government and IAEA relating to safeguards. It is part of the Treaty on the non-proliferation of nuclear weapons published in the Official Gazette no. 3/31 January 1970, and the Additional Protocol published in the Official Gazette no. 295/ 29.06.2000. The first discussion about Integrated Safeguards (IS) between the Nuclear Fuel Plant (FCN) representatives and IAEA inspectors ...
Hepatic injury and regeneration of the liver are associated with activation of hepatic stellate cells (HSC). Fibroblast growth factors (FGFs) and their receptors are important regulators of repair in various tissues. HSC express FGFR3IIIc as well as FGFGR4 and different spliced FGFR1IIIc and FGFR2IIIc isoforms which differ in the presence or absence of the acid box and of the first Ig-like domain. Expression of FGF9, known to be capable to activate the HSC FGFR2/3-isoforms, was increased in HSC in liver slice cultures after exposition to carbon tetrachloride, as an acute liver injury model. FGF9 significantly stimulated 3-H thymidine incorporation of hepatocytes, but failed to induce DNA synthesis in HSC despite the fact that FGF9 induced a sustained activation of extracellular signal-related kinases (ERK) 1/2. FGF9 induced an increased phosphorylation of Tyr436 of the fibroblast growth factor receptor substrate (FRS) 2, while phosphorylation of Tyr196 which is ...
More than 80% of the people of Nepal are farmers and 90% of the farmers do farming for subsistence. Agricultural productions contribute about 50% of country's GDP. Agricultural sector has been categorized as the top priority sector since many years. The environment of the country has also deteriorated substantially by the unplanned and unscientific use of natural resources such as air, soil, water, air and forest. Fertility of the soil has also been declining and studies show that productions in mountains is decreasing at a rate of 40 Kg/ha. Yr (1). The Terai, a narrow strip of land in the south, is in heavy pressure due to over exploitation and population growth (both natural and migratory). Shallow groundwater (shallow tube wells) is the main source of drinking water in Terai (the lowland region of Nepal). A study conducted by Department of Water Supply and Sewerage (DWSS) showed that more than 55% of Terai tube wells are microbiologically contaminated (2). There might be many ...
The Radiation Technology Center from IPEN-CNEN/SP, Brazil, developed a revolutionary design and national technology, a small-sized continuous run and multipurpose industrial gamma irradiator, to be used as a demonstration facility for manufacturers and contract service companies, which need economical and logistical in-house irradiation system alternatives. Also, to be useful for supporting the local scientific community on development of products and process using gamma radiation, assisting the traditional and potential users on process validation, training and qualification of operators and radioprotection officers. The developed technology for this facility consists of a continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m"2 of floor area, the ...
The computer program is developed based on Visual C++, which is equipped with a user-friendly interface of the input/output(I/O) and a display function for the measuring conditions. This program consists of three parts which are the port communication, PLC(Programmable Logic Controller) and the MCA(Multi Channel Analyzer) control parts. The communication type between the CPU of the PLC module box and the computer is selected as be the Rs-232 asynchronous type and the thread method is adapted in the development of the first part of the program. The PLC-related program has been developed so that the data communication between the PLC CPU and the computer could be harmonized with the unique commands which have already been defined in the PLC. The measuring space and time intervals, the start and end ROI(region of interest) values, and the allowable error limitation are input at each measurement in this program. Finally the controlling MCA program has been developed by ...
With the advance of science, rise of public interest in environmental matters, and continuing erosion of air quality, Federal and state regulators are demanding an increasing complex array of data concerning emissions produced by burning and detonating energetic materials. The US Department of Defense, one of the world`s largest consumers of energetic materials, now must characterize combustion products resulting from open burning/open detonation disposal operations. The catch-all phrase ``below detection limits`` no longer satisfies the regulators who now want testing to delve into the ppt level for volatile organic compounds and ppt level for semivolatile organic compounds. Regulators are also expanding their scope of interest and may soon be asking for emissions data on training operations such as artillery firing. Providing this type of information is no longer an impossibility. The Army, as the single manager of conventional munitions for the three military services, anticipated ...
Many of today's automated real-time testing systems for embedded systems were developed using expensive custom hardware and software. In this article they describe how to use commercially available off-the-shelf hardware and software to design and develop an automated real-time test systems for Embedded Programmable Logic Controller (PLC) Based Control Systems. The system development began with the implementation of the VALI/TEST Pro testing methodology as a means for structuring the testing. Using this methodology, they were able to decompose system requirement documents for a Personnel Safety System (PSS) into its high, intermediate and detail level requirements. next, the validation procedures for the PSS system were decomposed into testing units called builds, test runs and test cases. To measure the PSS system's test coverage three levels of system requirements were mapped to their respective unit level of test using a specially constructed validation matrix that ...
Calgary-based TAG Oil is an exploration company that manages 4.1 million acres of major producing oil and gas fields in New Zealand. The enormous Maui field, with 4 tcf of natural gas in place, has dominated the gas market in New Zealand by meeting nearly 90 per cent of the country's energy demand at costs much lower than world prices. However, the maturing field is in decline and will cease production by 2008. New gas field discoveries will only meet 60 per cent of the country's energy requirements for 5 additional years. Unless new large reserves of gas are discovered, the supply and demand situation will get worse. Lead time to place new production on-stream requires 5 to 10 years, which creates a large supply gap over the next decade. Public resistance to coal-fired power plants, new hydroelectric dams and nuclear power has left the country with no viable alternative to natural ...
A case study of a hypothetical offshore production fixed leg platform facility is presented. The purpose of the case study is to demonstrate the advantages offered by modern, fuel efficient large gas turbines in central power generation service for offshore production. The case study was presented using the Rolls- Royce RB211 large gas turbine with facility production of approximately 240,000 BPD of oil and 540 MMSCFD of associated gas. The gas was subjected to three stages of separation for removal of hydrocarbon liquids and water. The liquids, natural gas, and crude oil were exported from the production platform to an onshore receiving terminal. Gas compression is the service that requires the greatest amount of power for any given production facility. For this case study, gas compression represented approximately 70 per cent of the power ...
Gas distribution companies have long since paid great attention to improving the quality and safety of the gas supply service to the consumer. In particular the management of gas emergencies has always been a responsibility taken seriously by all sectors of the gas industry. Over the last few years, however, the concept and practices in risk management have been changing rapidly. This has involved gas companies in an on-going attempt to successfully define and establish clear computer assisted risk management practices. Risk management is the systematic use of management policy, procedures and means, with the aim to protect employees, the public, the environment and properties at an acceptable cost. This paper has the purpose of presenting: - the computer software of gas emergency management in use at Italgas S.p.A. for testing the performance of ...
Gas storage is a critical element in the natural gas industry. Producers, transmission and distribution companies, marketers, and end users all benefit directly from the load balancing function of storage. The unbundling process has fundamentally changed the way storage is used and valued. As an unbundled service, the value of storage is being recovered at rates that reflect its value. Moreover, the marketplace has differentiated between various types of storage services and has increasingly rewarded flexibility, safety, and reliability. The size of the natural gas market has increased and is projected to continue to increase towards 30 trillion cubic feet over the next 10 to 15 years. Much of this increase is projected to come from electric generation, particularly peaking units. Gas storage, particularly the flexible services that are most suited to electric loads, is crucial in meeting the needs of ...
A model for combined mass and heat transfer during nonisothermal gas absorption in a two-phase gas- liquid bubbly medium with a high gas content and/or large times of gas-liquid contact is suggested. Diffusion and thermal interactions between bubbles is taken into account in the approximation of a cellular model of a bubbly medium whereby a bubbly medium is viewed as a periodic structure consisting of identical spherical cells with periodic boundary conditions at a cell boundary. Distribution of concentration of dissolved gas, temperature distribution in liquid and coefficients of mass and heat transfer during nonisothermal absorption of a soluble pure gas from a bubble by liquid are determined. In the limiting case of absorption without heat release the derived formulas recover the expressions for isothermal absorption. (orig.). With 1 fig., 1 tab. [Deutsch] Es ...
The Ordos Basin is a typical lapped basin, including three sequences of strata: early Paleozoic, late Paleozoic and Mesozoic, with a total thickness of 4000-6000m. Impermeable sealing beds are well developed at the top and base of the upper Paleozoic sequence, separating it from the Mesozoic and the lower Paleozoic strata to form an independent petroleum system. In this petroleum system, the source rocks are widely distributed coals and dark mudstones occurring in the Carboniferous-lower Permian coal measures, with a thickness of 10-15 and 40-60m, respectively. The reservoirs are mainly early Permian tight sandstones, mostly with a porosity of 4-8% and a permeability of 0.1-1.0x10{sup -3}{mu}m{sup 2}. The regional cap rock is a 100-150m thick mudstone in the upper Permian strata. The structural framework of the basin is a huge asymmetric syncline, dipping gently toward the east and north, and steeply toward the south and west. Well data show that gas-saturated, ...
Limited demand and high cost has prevented the construction of hard rock caverns in this country for a number of years. The storage of natural gas in mined caverns may prove technically feasible if the geology of the targeted market area is suitable; and economically feasible if the cost and convenience of service is competitive with alternative available storage methods for peak supply requirements. It is believed that mined cavern storage can provide the advantages of high delivery rates and multiple fill-withdrawal cycles in areas where salt cavern storage is not possible. In this research project, PB-KBB merged advanced mining technologies and gas refrigeration techniques to develop conceptual designs and cost estimates to demonstrate the commercialization potential of the storage of refrigerated natural gas in hard rock caverns. Five regions of the U.S.A. were studied for underground storage development and PB-KBB ...
A developed flue gas desulfurization and dust removal process with a cross-flow moving bed filled with activated coke (AC) was tested on a pilot scale with the gas treatment capacity of 1000 mg x h(-t). The results show that a easy-operating and stable-running pilot-scale testing equipment can be reached, and under the conditions of testing space velocity, the feed gas temperature of 120 degrees C, SO2 concentrations of 3232-6006 mg x m(-3) and dust concentration of 89.3-1599.7 mg x m(-3), the high efficiency of flue gas desulfurization and dust removal is reached with the purity of dust less than 50 mg x m(-3). In the technology, the spent AC was regenerated by heating, and the SO2 concentration in the desorption gas is about 40.1%, which can be efficiently recovered as a sulfur resource. Favorable economy benefit can be reached by using the process. PMID:16850821
The University of Groningen (RUG) has developed an expert system on cleaning of biomass producer gas. This work was carried out in close co-operation with the Biomass Technology Group B.V. (BTG) in Enschede, The Netherlands within the framework of the EC supported JOR3-CT95-0084 project. The expert system was developed as a tool for the designer-engineer of downstream gas cleaning equipment and consists of an information package and a flowsheet package. The packages are integrated in a client/server system. The flowsheeting package of the expert system has been designed for the evaluation of different gas cleaning methods. The system contains a number of possible gas cleaning devices such as: cyclone, fabric filter, ceramic filter, venturi scrubber and catalytic cracker. The user can select up to five cleaning steps in an arbitrary order for his specific gas cleaning problem. After ...
Precondition for the low-NO operation of gas turbine burners is the generation of as homogeneous as possible a gaseous fuel/air mixture. Such a burner behavior can be achieved by selective adaptation of the flow and injection. A computing model is introduced that calculates the dynamically balanced GASs/droplet flow through numerical solution of the transport equations in a curved orthogonal coordinate system. The feedback reaction of the fuel droplets to the gas phase is considered by source terms and/or sink terms. Test computations were carried out for comparison with analytical solutions from the flow mechanics and validated by comparison with measurement results. Droplet motion and evaporation were checked by means of published experimental results on single droplets. For the validation of the developed computing technique, model tests were carried out with water in place of fuel. It is pointed out that the choice of different parameters ...
The regular occurrence of large-scale earthquakes in Japan necessitates the use of earthquake disaster prevention systems that focus on gathering damage information on gas supply facilities immediately after an earthquake strikes and minimizing the damage. This paper discussed the development of an earthquake damage estimation system for city gas pipelines that can show damage information in real-time by using earthquake records obtained from densely deployed earthquake observation networks and the most advanced telecommunication and information technologies. The paper summarized the earthquake damage estimation system (EDES) and Toho Gas disaster prevention measures. Specific topics that were discussed included the Toho Gas supply method; earthquake countermeasures; construction of computer systems; normal and emergency operation of EDES; and verification of functions in actual earthquakes. It was ...
This paper describes the safety gas management system utilizing public telephone cables. Buyo Gas Co., Ltd. has installed about 100 governors for exclusive-use or use in the districts to control the gas supply to the consumers. A gas safety management system has been developed. This system consists of a pressure sensor, the terminals of gas leak alarms, and their masters. The features lie in that the system can utilize public cables, is operative at interruption of power service, can correspond to emergency situations, serves to save the cost, and can display the data constantly. For electric facilities in a governor room and the NTT cable service work, sufficient agreement with the possessor is required. In the case of non-utility electric facilities, some restrictions are imposed on the cable work for laying from privately-owned transformers, etc. Insurance for the facilities is ...
A laboratory-scale multi-layer system was developed for the adsorption of PCDD/Fs from gas streams at various operating conditions, including gas flow rate, operating temperature and water vapor content. Excellent PCDD/F removal efficiency (>99.99%) was achieved with the multi-layer design with bead-shaped activated carbons (BACs). The PCDD/F removal efficiency achieved with the first layer adsorption bed decreased as the gas flow rate was increased due to the decrease of the gas retention time. The PCDD/F concentrations measured at the outlet of the third layer adsorption bed were all lower than 0.1ng I-TEQNm-3. The PCDD/Fs desorbed from BAC were mainly lowly chlorinated congeners and the PCDD/F outlet concentrations increased as the operating temperature was increased. In addition, the r...
Device for separating and collecting ultrafine atomized powder from the gas stream of a gas atomizing apparatus comprises a housing having an interior wall oriented at an angle relative to horizontal so as to form a downwardly converging, conical expansion chamber, an inlet conduit communicated to the expansion chamber proximate an upper region thereof for receiving the gas stream, and an outlet proximate a lower region of the expansion chamber. The inlet conduit is oriented at a compound inclined angle (with respect to horizontal) selected to promote separation and collection of powder from the gas stream in the expansion chamber. The compound angle comprises a first entrance angle that is greater than the angle of repose of the powder on the housing interior wall such that any powder accumulation in the inlet conduit tends to flow down the wall toward the outlet. The second angle is selected generally ...
A series of experimental measurements of ozone concentration produced by irradiation of noble gas (He, Ne, and Ar)-O_2 and noble gas-O_2- SF_6 mixtures with energetic (MeV) helium and lithium ions are reported. Continuous irradiations at dose rates of 10"1"5-10"1"7 eV cm"-"3 S"-"1 for a few hundred milliseconds were used. The resulting ozone concentration was found to be nonlinear with dose rate for a given irradiation time. This nonlinearity was effectively reduced by an increase in noble gas pressure. Few mole percent addition of SF_6 generally resulted in an increase in the ozone concentration. This increase was highest for lower noble gas pressures and longer irradiation times. Further SF_6 addition, however, caused a reduction in the ozone concentration. Results are explained by considering the relevant reactions responsible for ozone production and loss.
The main objective of the present study is to investigate Turkey's natural gas (NG) demand and supplies by giving the structure of the Turkish gas industry, NG pricing policy, and NG agreements. Turkey began to import NG from Russia in 1987 under a contract that provided for the delivery of 6 billion cubic meters annually (Bcma) for 25 years. The first contract, signed in 1988, stipulates delivery of 2 Bcma over a 20-yr period. The build-up of the Turkish gas market started by introducing gas in power generation in 1987 and in fertilizer production in 1988. Later contracts provide for total imports of 4 Bcma from the late 1990s. NG sales started at 0.5 Bcm in 1987 and reached to around 16 Bcm in 2001. Turkish NG demand is projected to increase extremely rapidly in coming years, with the prime consumers expected to be NG-fired electric power plants and industrial users. (author)
The NATural GAS model is an integrated model of the European wholesale gas market providing long-run projections of supply, transport, storage and consumption patterns in the model region, aggregated in 5-year periods, distinguishing two seasons (winter and summer). Model results include levels of investment in the various branches, output and consumption, depletion of reserves and price levels. The NATGAS model computes long-term effects of policy measures on future gas production and gas prices in Europe. NATGAS is an equilibrium model describing behaviour of gas producers, investors in infrastructure (pipeline, LNG capacity, as well as storage), traders and consumers. NATGAS covers the main European demand regions, including the United Kingdom, Germany, the Netherlands and Italy. Moreover, it covers the main origins of supply on the European market, such as Russia, Norway, ...
Uranium enrichment by gas centrifugation relies on the pressure diffusion of the isotopes when their gaseous mixture is submitted to the pressure diffusion in the strong radial pressure gradient due to the centrifugal force in a very rapidly rotating cylinder. To compute the isotope separation in a gas centrifuge, the viscous compressible Navier-Stokes equations are solved for the mixture, then the diffusion equations are solved for the isotopes. As far as the separation performance is concerned, the models deal with the steady state of the axi-symmetric gas motion in the rotating cylinder. The numerical tools are briefly presented: first, the MOLINA code which numerically solves the axi-symmetric gas motion in the specific conditions of rapid rotation by use of a change of variables suited to the high density gradient and by use of a Marker And Cell method; then, the diffusion equations solver which ...
A method of treating final products from a flue gas desulfurization. The flue gas desulfurization is carried out by the absorption of sulfur oxide in a spray dryer with a suspension which contains lime, or in a reactor with a dry, fine-grained, absorbent which contains lime. Prior to desulfurization, the fly ash carried along by the flue gas which is to be desulfurized is separated entirely, partially, or not at all from the flue gas, and the final products from the flue gas desulfurization, prior to any further treatment thereof, amount to 1-99% by weight, preferably 1-70% by weight, of fly ash, and 1-99% by weight, preferably 30-99% by weight, of the sum of the desulfurization products, preferably calcium sulfite hemihydrate, and/or calcium sulfite, and/or calcium sulfate dyhydrate, and/or calcium sulfate hemihydrate, and/or calcium sulfate, as well as residue of the absorbent. ...
Carbonaceous solid material such as coal is gasified in a fast fluidized bed gasification system utilizing dual fluidized beds of hot char. The coal in particulate form is introduced along with oxygen-containing gas and steam into the fast fluidized bed gasification zone of a gasifier assembly wherein the upward superficial gas velocity exceeds about 5.0 ft/sec and temperature is 1500.degree.-1850.degree. F. The resulting effluent gas and substantial char are passed through a primary cyclone separator, from which char solids are returned to the fluidized bed. Gas from the primary cyclone separator is passed to a secondary cyclone separator, from which remaining fine char solids are returned through an injection nozzle together with additional steam and oxygen-containing gas to an oxidation zone located at the bottom of the gasifier, wherein the upward gas ...
The fuel-injection system of the Niigata 6L 16X-AG dual-fuel engine is structured to steadily supply injected fuel during diesel-engine operation, and to distribute oil at a low rate to all the cylinders during gas-engine operation. The dual-fuel engine is started by the diesel engine operation and is changed over to gas-engine operation when the load increases. This change over is done automatically with a link mechanism. Regarding the gas-supply system, the changing pressure of supply gas is controlled by a pressure control valve which is stable and most adequate for the engine. The dual-fuel engine has the following features: (1) a high compression ratio is adopted, which reduces fuel consumption and thermal efficiently; (2) if the supply of gas decreases or stops, while continuing loaded operations, it can immediately shift to diesel engine operation automatically and continue ...
The Natural Gas Vehicle Challenge `92, organized by Argonne National Laboratory and sponsored by the US Department of Energy, the Energy, Mines, and Resources - Canada, the Society of Automotive Engineers, and many others, resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark-ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck, donated by General Motors, teams of college and university student engineers strived to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine-out and tailpipe emissions of regulated ...
We investigate the formation and evolution of dwarf galaxies in a high resolution, hydrodynamical cosmological simulation of a Milky Way sized halo and its environment. Our simulation includes gas cooling, star formation, supernova feedback, metal enrichment and UV heating. In total, 90 satellites and more than 400 isolated dwarf galaxies are formed in the simulation, allowing a systematic study of the internal and environmental processes that determine their evolution. We find that 95% of satellite galaxies are gas-free at z=0, and identify three mechanisms for gas loss: supernova feedback, tidal stripping, and photo-evaporation due to re-ionization. Gas-rich satellite galaxies are only found with total masses above ~ 5x10^9 solar masses. In contrast, for isolated dwarf galaxies, a total mass of ~ 10^9 solar masses constitutes a sharp transition; less massive galaxies are predominantly ...
In 1983, the first modern urban transit bus powered by an alternative transportation fuel took to the roads in the USA. A little more than a decade later, about 2.5% of all USA buses are powered by alternative transportation fuels and about 20% of the new bus orders for delivery by 1998 will be powered by alternative fuels, mostly by natural gas. There are over 2,200 natural gas buses in operation or on order, plus about 600 additional buses powered by other alternative fuels. When these orders are completed, alternative fuel buses will constitute over 4.4% of the urban bus fleet in the USA. The widespread use of natural gas buses in the USA provides an important transition pathway for hydrogen vehicles because of the similarities between distribution, refueling and onboard energy storage technologies for the two fuels. Projects demonstrating advanced hybrid-electric buses powered by natural gas or ...
The American Natural Resources System has been attempting to obtain the financing commitments and regulatory approvals necessary to construct the nation's first commercial-scale coal-gasification plant. It would employ the same technology as Sasol plants of South Africa and much of the same hardware as the Sasol II plant now approaching completion. But instead of converting the gas that comes out of the gasifier vessels into liquid hydrocarbons, the proposed plant would upgrade the gas to a Btu-content equivalent to that of natural gas. It could be mixed, transported, and utilized as a constituent part of the natural gas stream. The plant would be located in North Dakota and would utilize coal as the feedstock. North Dakota lignite gasifies very efficiently and, since the plant would be located at the mine mouth, the low-Btu quality of the coal is not a particularly adverse factor. The ...
Gas-solid chromatography was used to determine the Henry`s law second gas-solid virial coefficients within the temperature range of 314--615 K for ethane, propane, butane, isobutane, pentane, hexane, heptane, chloromethane, dichloromethane, trichloromethane, tetrachloromethane, trichlorofluoromethane (Freon 11), chlorodifluoromethane (Freon 22), dichlorodifluoromethane (Freon 12), methyl ether, ethyl ether, and sulfur hexafluoride with Carbopack B, a microporous carbon adsorbent. The temperature dependence of the second gas-solid virial coefficients of these adsorbates was used in conjunction with analyses based on a graphical method, a single-surface numeric integration method, a single-surface analytic expression method, and a two-surface analytic expression method to determine the gas-solid interaction energies and other parameters. The interaction energies were correlated with a ratio of the ...
Ozone formation by a pulse positive corona discharge generated in the gas phase between a planar high voltage electrode made from reticulated vitreous carbon and a water surface with an immersed ground stainless steel plate electrode was investigated under various operating conditions. The effects of gas flow rate (0.5-3 litre min"-"1), discharge gap spacing (2.5-10 mm), applied input power (2-45 W) and gas composition (oxygen containing argon or nitrogen) on ozone production were determined. Ozone concentration increased with increasing power input and with increasing discharge gap. The production of ozone was significantly affected by the presence of water vapour formed through vaporization of water at the gas-liquid interface by the action of the gas phase discharge. The highest energy efficiency for ozone production was obtained using high voltage pulses of approximately 150 ns ...
The usually low wear resistance of titanium materials can be increased by the thermochemical surface treatment nitriding. In result of comparative investigations of gas and plasma nitriding it will be shown that it is possible to obtain a specific variation of the properties in the highly stressed case by means of these both technologies on example of the (#alpha#+#beta#) alloy Ti-6Al-4V. Gas and plasma nitriding was carried out in the temperature range from 650 to 800 C over 4 to 48 h in different gas atmospheres, i.e. 100% NH_3 (gas), 100% N_2 (gas and plasma), 20% H_2 + 80% N_2 and 20% Ar + 20% H_2 (plasma). The temperature range was fixed in the middle of (#alpha#+#beta#) region, because the core properties are influenced negative in the field of #beta#-transustemperature. The relations between the applied nitriding technologies, the layer structure (chemical, phases, ...
Grout has been evaluated as a means of containing low-level radioactive waste for long-term disposal. Concerns about hydrogen and reactive gas generation in the Hanford Site grout disposal facility lead to the development of the G3 model, which has predicted buildup of radiolytically formed gases in the grout region and their migration to air-filled regions. The G3 model is a one-dimensional code that couples models of gas diffusion with two-phase gas and liquid flow. It was coupled to a compartment diffusion model and these models predicted the concentrations of hydrogen I nitrous oxide, and other gases in air-filled regions of the grout disposal facility. The results have served as the technical basis for safety studies. A unique finding of the G3 model was that a liquid return, or expulsion of unbound liquid from the grout region, could occur. This liquid return is driven by displacement caused by ...
A survey has been made in relation with the improvement project intended of energy conservation, and reduction of global warming gas emission at the Bobovdol thermal power plant located in the suburb of Sofia, the capital of the Republic of Bulgaria. The existing Bobovdol power plant having a total capacity of 630 MW with three generators is a coal burning thermal power plant having been used already for 23 to 27 years, hence over-aged. The survey has discussed an improvement project of scrap-and-build type to make the plant a high-efficiency gas combined cycle power plant using gas turbines. The project calls for building 210-MW gas combined power generation facilities having 70-MW gas turbines, one each in three stages in 2007, 2012 and 2017. As a result of the discussions, the fuel consumption reducing rate was found to reach 37.99%, whereas the cumulative energy saving quantity ...
Externally Fired Combined Cycles (EFCCs) can increase the amount of electricity produced from ash bearing fuels up to 40%, with overall powerplant efficiencies in excess of 45%. Achieving such high efficiencies requires high temperature-high pressure air heaters capable of driving modern gas turbines from gas streams containing the products of coal combustion. A pilot plant has been constructed in Kennebunk, Maine to provide proof of concept and evaluation of system components. Tests using pulverized Western Pennsylvania bituminous coal have been carried out since April, 1995. The ceramic air heater extracts energy from the products of coal combustion to power a gas turbine. This air heater has operated at gas inlet temperatures over 1,095 C and pressures over 7.0 atm without damage to the ceramic tube string components. Stable gas turbine operation has been achieved with energy ...
A natural gas and diesel dual-fuel turbocharged compression ignition (CI) engine is developed to reduce emissions of a heavy-duty diesel engine. The compressed natural gas (CNG) pressure regulator is specially designed to feed back the boost pressure to simplify the fuel metering system. The natural gas bypass improves the engine response to acceleration. The modes of diesel injection are set according to the engine operating conditions. The application of honeycomb mixers changes the flowrate shape of natural gas and reduces hydrocarbon (HC) emission under low-load and lowspeed conditions. The cylinder pressures of a CI engine fuelled with diesel and dual fuel are analysed. The introduction of natural gas makes the ignition delay change with engine load. Under the same operating conditions, the emissions of smoke and NO{sub x} from the dual-fuel engine are both reduced. The HC and ...
Corrosion control on gas pipelines plays an important role on the assessment of pipeline integrity and reliability. In many countries a great extension of buried pipelines is used on transport and distribution systems. This extension will be certainly increased in a near future due to the increasing consumption of natural gas. Inadequate corrosion control can drive to pipeline failures, bringing up the possibility of accidents in populated or environmental protected areas, bringing together severe economical, legal and environmental consequences. Corrosion is frequently considered as a natural and inevitable phenomenon. Based upon this assumption, some recommendations are included on design standards of gas pipelines in order to compensate its detrimental effect. The aim of this work is to present a review of the correlation between external corrosion process and the guidelines established during the project phase of ...
The major driver to enhance the efficiency of the simple gas turbine cycle has been the increase in process conditions through advancements in materials and cooling methods. Thermodynamic cycle developments or cycle integration are among the possible ways to further enhance performance. The current paper presents the possibilities and advantages from the LOTHECO natural gas-fired combined cycle concept. In the LOTHECO cycle, low-temperature waste heat or solar heat is used for the evaporation of injected water droplets in the compressed air entering the gas turbine's combustion chamber. Following a description of this innovative cycle, its advantages are demonstrated by comparison between different gas turbine power generation systems for small and large-scale applications, including thermodynamic and economic analysis. A commercial gas turbine (ALSTOM GT10C) has been selected and ...
Inert gas contamination, structure and mechanical properties of consolidated high-Ni alloy powder material were studied to improve its characteristics. In experiment, the chemical composition and fraction of porosity in cross sections of Alloy 625 powder were examined which was produced by Ar gas atomization method impinging supplemental gas jet onto accumulated alloy powder in the bottom of a tank for rapid cooling. The structure and mechanical properties of the alloy rod were also examined which was produced by hot hydrostatic pressing or hot extrusion of the powder filled into a capsule. As a result, although Ar content included in the powder produced by Ar gas atomization method decreased with reduction in grain size, the fine powder less than 22{mu}m still included Ar of nearly 0.5mass-ppm. Obvious correlation was found between the fraction of porosity in powder cross sections and Ar in the powder. ...
We used a dense phase tower as the reactor in a novel semi-dry flue gas desulfurization process to achieve a high desulfurization efficiency of over 95% when the Ca/S molar ratio reaches 1.3. Pilot-scale experiments were conducted for choosing the parameters of the full-scale reactor. Results show that with an increase in the flue gas flow rate the rate of the pressure drop in the dense phase tower also increases, however, the rate of the temperature drop decreases in the non-load hot gas. We chose a water flow rate of 0.6 kg/min to minimize the approach to adiabatic saturation temperature difference and maximize the desulfurization efficiency. To study the flue gas characteristics under different processing parameters, we simulated the desulfurization process in the reactor. The simulated data matched very well with the experimental data. We also found that with an increase in the Ca/S molar ratio, the ...
A geologic sequestration pilot in the Thornton gas field in Northern California, USA involves injection of up to 4000 tons of CO{sub 2} into a stacked gas and saline formation reservoir. Lawrence Berkeley National Laboratory (LBNL) is leading the pilot test in collaboration with Rosetta Resources, Inc. and Calpine Corporation under the auspices of the U.S. Department of Energy and California Energy Commission's WESTCARB, Regional Carbon Sequestration Partnership. The goals of the pilot include: (1) Demonstrate the feasibility of CO{sub 2} storage in saline formations representative of major geologic sinks in California; (2) Test the feasibility of Enhanced Gas Recovery associated with the early stages of a CO{sub 2} storage project in a depleting gas field; (3) Obtain site-specific information to improve capacity estimation, risk assessment, and performance prediction; (4) Demonstrate and test ...
The thermodynamic framework that was developed in a previous work [Vrachnos et al. Ind. Eng. Chem. Res. 2004, 43, 2798] for the description of chemical and vapor-liquid equilibria of carbon dioxide, hydrogen sulfide, and their mixtures in aqueous methyldiethanolamine (MDEA) solutions is revised and extended in this study to the absorption of carbon dioxide into aqueous monoethanolamine (MEA) solutions and aqueous MDEA-MEA blends. The results of the model are compared with experimental data taken from the literature. Very satisfactory predictions of acidic gas vapor-liquid equilibrium over MDEA, MEA, and their blends at various concentrations, acidic gas loadings, and temperatures are obtained.
The report gives results of an analysis of the effect of the availability of a flue gas desulfurization system on the ability of an individual power plant to generate electricity at its rated capacity. (The availability of anything is the fraction of time it is capable of service, whether or not it is actually in service.) Also analyzed are its effects on a power generating system (a group of several coal-, oil-, and gas- fired power plants plus nuclear and hydroelectric plants).
For light water reactors, loss of coolant is an important point in safety analysis, whereas for gas-cooled reactors the ingress of water into the core region is an incident of safety relevance. The applicability of the computer code system GAMTEREX to pebble beds of spherical high-temperature gas-cooled reactor fuel elements with simulated water ingress is verified by experiment. The measurements were performed at a Siemens-Argonaut reactor, using its ring core as a driver zone for a pebble-bed core in the center of the reactor.
Independent drilling contractors own all offshore drilling rigs, which they lease to oil and gas companies for use in their pursuit of their exploration and development plans. Oil and gas companies' demand for these rigs can vary quickly and dramatically in response to changes in the world market for oil and natural gas. As a result, drilling contractors often try to manage excess capacity by idling rigs (known in the industry as "stacking" a rig), reactivating them when demand recovers. This paper examines these decisions over the course of a price cycle in 1998-2000 to investigate the role of firm and rig heterogeneity in determining drillers' decisions about idling and reactivating capacity.
Environmental studies in slip-stream process development units at SCGP-1, Shell's advanced coal gasification demonstration plant, located near Houston, Texas, have demonstrated that the gas and water effluents from the Shell Coal Gasification Process (SCGP) are environmentally benign on a broad slate of coals. This report presents the results of those environmental studies. It contains two major subjects, which describe, respectively, the experiments on gas treating and the experiments on water treating. Gas treatment focused on the performance of aqueous methyldiethanolamine (MDEA) and sulfinol-M. 8 refs., 24 figs., 13 tabs.
Results are given for deep-level petroleum and gas drilling probes in various coastal zones of Southern Sakhalin covering the Poronai depression and the Aniv Bay trough. The exploratory probes indicate that the Middle Miocence deposits of the Boundary trough contain commercial-size deposits of petroleum, that commercial-size gas deposits are in the upper Myocene deposits of the Aliv Bay trough, and that the upper Cretaceous and Cenozoic deposits of the eastern section of Southern Sakhalin lack folded deformations. 7 references, 2 figures.
Carbon monoxide, H{sub 2}, and CO{sub 2} in synthesis gas can be converted to CH{sub 4} by employing a triculture of Rhodospirillum rubrum, Methanosarcina barkeri, and Methanobacterium formicicum. Trickle-bed reactors have been found to be effective for this conversion because of their high mass-transfer coefficients. This paper compares results obtained for the conversion of synthesis gas to CH{sub 4} in 5-cm- and 16.5-cm-diameter trickle-bed reactors. Mass-transfer and scale-up parameters are defined, and light requirements for R. rubrum are considered in bioreactor design.
Results of analytical study of early stages of a single star evolution are used investigation of the rotational fragmentation of the collapsing gas-dust cloud which leads to formation of two types of binaries. Wide ..cap alpha..-systems (Psub(orb) > or approximately 100 yrs) with usually unequal masses of components are formed before the formation of gas-dust core in hydrostatical equilibrium. Close ..beta..-systems (Psub(orb) < or approximation 100 yrs) with usually nearly equal masses of components are formed in the course of the collapse of gas-dust core.
The production of and emission factors for the air-polluting matters sulfur dioxide, nitrogen oxides, carbon monoxide, hydrocarbons (esp. benz(a)pyrene), aldehyde and soot with regard to natural gas, excluding process furnaces, are dealt with. The comparison with other fuels indicates that only as to nitrogen oxides and carbon monoxide are emission factors equal in order of magnitude. As a summary measure of all air-polluting matters the emission index as proposed already in 1972 is applied. It shows emissions with single-room furnaces for heating oil EL to be six times as high as with natural gas; with black-coal briquettes the factor is at least 33, with wood chimneys about 200.
The Eighth Indirect Liquefaction Contractors' Review Meeting was held November 15-17, 1988 at the Pittsburgh Hyatt Hotel. Twenty-eight presentations were made by contractors, invited speakers, and Pittsburgh Energy Technology Center R and D personnel. Six areas of research were covered: synthesis gas conversion to oxygenates; light hydrocarbon gas conversion; slurry reactor hydrodynamics; production, clean-up and conversion to hydrocarbon fuels; Fischer-Tropsch products upgrading; and, synthesis gas bioconversion. The meetings also included a panel discussion on direct methane conversion research. Individual projects are processed separately for the data bases.
Low-dust flue gases can be washed efficiently of SO/sub 2/, and the flue gas heat can be utilized. The residual heat fraction still required by the process is characterized by a temperature of 15/sup 0/K above the temperature of the purified flue gas. Marketable crystalline ammonium sulfate is produced. The high efficiency and low heat consumption are achieved by combining all process stages in a single, fully integrated cycle process free of heat and materials losses. The process is characterized by high efficiency, low investment and operating costs, recovery of thermal energy, and production of an ammonium sulfate fertilizer.
Purge water from a typical wet flue gas desulfurization system contains myriad chemical constituents and heavy metals whose mixture is determined by the fuel source and combustion products as well as the stack gas treatment process. A well-designed water treatment system can tolerate upstream fuel and sorbent arranged in just the right order to produce wastewater acceptable for discharge. This article presents state-of-the-art technologies for treating the waste water that is generated by wet FGD systems. 11 figs., 3 tabs.
This manual is intended to provide a guide to the use of the Flue Gas Desulfurization Information System (FGDIS) data base which is a collection of data files consisting of information pertaining to the design and performance of flue gas desulfurization (FGD) systems. The files are stored at the U.S. Environmental Protection Agency National Computer Center (NCC), Research Triangle Park, NC. Access to these files and manipulation of the data therein is accomplished via System 2000, general data base management system developed by INTEL Corp. and supported by the NCC Univac 1100 hardware.
Here I provide a brief overview of recent experimental gas-phase measurements using the Selected-Ion Flow Tube or SIFT technique at 294#+-#2 K with helium buffer gas at 0.35 Torr for reactions which remove electrons from the C_6_0 molecule or donate electrons to singly and multiply-charged C_6_0 cations. The results of these measurements have provided new insight into physicochemical aspects of electron transfer and have revealed the occurrence of unprecedented electron transfer reactions at thermal energies. (author).
With the help of heat balance equation and high temperature thermodynamic function, the calibration relation of jet temperature with discharge power, gas flow rate was obtained for nitrogen thermal plasma. It was shown that the results were agreed with the principle of similarity. The jet temperature was a function of Peff/f, instead of a general two variables function of Peff and f, which were effective discharge power and working gas flow rate, respectively. A related discussion has been given; it will be referable to thermal plasma applications. (authors)
... Biogas: The green gas? | EurActiv Biogas has become an attractive alternative source of energy in Europe as the renewable fuel ...Graduate Programme Research Analyst Junior Consultant Training Coordinator Post an EU job Biogas: The green gas? Published: 09 April 2010 |...Updated: 06 July 2010 Biogas has become an attractive alternative source of energy in Europe as the renewable fuel serves several policy priorities, ranging from ... Policy Summary Biogas is a renewable energy source that can be used for heating or electricity production. If compressed, it can ...
The inelastic scattering of the beam and the residual gas molecules in RHIC could represent one of the limitations on the beam life time and emittance growth. This report covers the dominant central nuclear collisions influence on the beam lifetime and transverse emittance growth. The cross sections for the beam-gas electron radiative captures are an order of magnitude smaller. The capture cross sections include the radiative and non-radiative capture, and the capture from the electron-positron pair creation from the 'vacuum capture'.