... A OPTIMUM FOR THE GASDYNAMIC SYSTEM IN A FAST-AXIAL-FLOW CO2 LASER by ... discharge mixture, in a fast-axial-flow CO2 laser, can be ...

... INFLUENCE OF FLOW VELOCITY ON THE OUTPUT POWER OF HIGH PRESSURE CW CO 2 LASERS by ... HIGH PRESSURE CW CO2 LASERS ...

Sep 1, 2011 ... Title: Biotic and abiotic factors regulating forest floor CO2 flux across a range of forest age classes in the southern Appalachians. Author: Vose ...

The degradation of TCE (C2HCl3) to carbon dioxide (CO2) and chloride (Cl-) has been reported to occur during thermal remediation of subsurface environments. The overall goal of this study was to evaluate abiotic degradation of TCE at el...

Using CO2 & Algae to Treat Wastewater and Produce Biofuel Feedstock Tryg Lundquist Cal Poly State of the Industry and Growth � Algae's Role in WW Treatment � CO2's New Role � Research at Cal Poly � Future Work/MG 0.3 MGD average flow per facility #12;Reclaimed Algae Bacteria O2 ...

The productivity of many tropical wet forests is generally limited by bioavailable phosphorus (P). Microbial activity is a key regulator of P availability in that it determines both the supply of P through organic matter decomposition and the depletion of bioavailable P through microbial uptake. Both microbial uptake and mineralization occur rapidly, and their net effect on P availability varies ...

The 18O/16O ratio of CO2 is a potentially powerful tracer of carbon dioxide fluxes from the soil to the atmosphere, which is influenced by complex interactions involving both biotic and abiotic soil processes. We use a simplified experimental approach and numerical simulations to examine in isolation the 18O exchange between CO2 and ...

... flowing CO2, sealed CO2, dye, helium/cadmium, helium/neon, heterojunction ... and notes; manufacturing criteria, problems, and burn-in; quantitative ...

Reducing atmospheric concentration of carbon dioxide (CO2) is a key challenge of the 21st century. One solution studied by several authors is the transformation, in situ, of CO2 into carbonate minerals such as calcite, magnesite or siderite. The precipitation of carbonates following CO2 injection requires specific ...

Atmospheric [CO2] is rising, with significant consequences for plant function in natural and managed ecosystems. Currently we cannot fully explain the effects of elevated [CO2] on vegetation under field conditions, where interactions with abiotic and biotic factors are important. To better ...

... CO2. Descriptors : *MEASUREMENT, *GAS FLOW, HIGH TEMPERATURE, ELECTRON BEAMS, SUPERSONIC FLOW. ...

In models of the global carbon cycle, the pCO2 of the atmosphere is more sensitive to the chemistry of the high-latitude surface ocean than the tropical ocean. Because sea-surface nutrient concentrations are generally high in the high latitudes, pCO2 sensitivity to high-latitude forcing also determines pCO2 ...

It is reported that the temperature rise of the discharge mixture, in a fast-axial-flow CO2 laser, can be decreased by increasing both the mass flow rate and the speed of the mixture through the laser tube. However, increasing the mixture speed, in a prac...

The properties of gas flow parameters in fast axial flow CO2 lasers are studied theoretically for the purpose of proposing pneumatic measures to improve laser performance. Through numerical analysis, relationships between speed, temperature, total tempera...

... EXPERIMENTAL STUDY OF GAS KINETICS OF A FAST-AXIAL FLOW KILOWATT CO2 LASER by ... Actually, a fast axial-flow ...

...nitrogen oxides (NOX ), and carbon dioxide (CO2 ) emissions, volumetric flow, and opacity data...SO2 emissions, volumetric flow, NOX emissions, opacity, CO2 emissions and SO2 emissions removal by...

... Title : Energy Transformation Properties and Mechanisms in Transverse Flow Discharged CO2 Lasers. Descriptive Note : Journal article. ...

Relict Holocene carbonate spring deposits containing diverse biotic and abiotic depositional textures are present at Fall Creek cold sulphur springs, Alberta, Fairmont Hot Springs, British Columbia, and Hot Creek cold springs, British Columbia. The relict deposits are formed mainly of low-magnesium crystalline calcite contained in laterally continuous strata. ...

The rising atmospheric CO(2) concentration, increasing temperature and changed patterns of precipitation currently expose terrestrial ecosystems to altered environmental conditions. This may affect belowground nutrient cycling through its intimate relationship with the belowground decomposers. Three climate change factors (elevated ...

Several scenarios for prevascular plant weathering are presented. The rise of vascular plants is examined in order to determine how levels of atmospheric CO2 could have been affected. It is concluded that in order to prohibit unreasonably high levels of atmospheric CO2, weathering during the Precambrian and early ...

The determination of geochemical and biogeochemical processes in subglacial environments is critical to our understanding of processes of terrestrial chemical denudation and global biogeochemical cycles in glaciersed environments. This study examines current subglacial biogeochemical weathering models using PHREEQCi, a computer-based speciation mass-balance (SMB) model, parameterised using ...

Effects of isosorbide dinitrate (ISDN) on coronary flow and arterial prostaglandin (PG) concentrations were investigated, using dog heart-lung preparations. Two kinds of gases (low and high CO2 gases) were used for the artificial respiration. Low CO2 gas contained 55% O2 and 0.2% ...

... centerbody combustor configurations, due to annular air flow and central CO2 flow; and (b) the two-dimensional mixing-layer configuration, due to ...

A thermal analysis of the compressible CO2 flow for the Portable Fire Extinguisher (PFE) system has been performed. The purpose of this analysis is to determine the discharged CO2 mass from the PFE tank through the Temporary Sleep Station (TeSS) nozzle in...

column Rotameter CO2 sensor Data logger CO2 sensor Data logger Computer Anemometer CO2 cylinder Mass flow column Rotameter DO sensor Data loggerComputer Anemometer N2 cylinder Blower Deionized water Fig. 2 for the lowest air flows ...

This study presents the interannual CO2 exchange of a semiarid shrubland overlying a carbonaceous substrate where abiotic processes may interact with biological processes in the ecosystem carbon cycle. Estimated by the eddy covariance technique and two different gap-filling models (RBF neural network and MDS �Marginal Distribution ...

... Accession Number : ADD146391. Title : CO2 Corrosion of API N-80 Steel at 71 C (160 F) in Two-Phase Flow Systems. Descriptive ...

The paper describes the rapid flow of a gas mixture in a fast-axial flow kilowatt level CO2 laser. A high-flow-velocity wind tunnel is introduced. Gas pressure, gas flow velocity, and its method of measurement are analyzed. A wind tunnel was constructed a...

High latitude oceans are major sinks for atmospheric carbon dioxide (CO2) but so far the extensive sea ice cover has been considered inert with respect to gas exchange with the atmosphere. There are growing observations that sea ice exchanges CO2 directly with the atmosphere, highlighting the need in understanding ...

The atmospheric CO(2) concentration [CO(2)] has been increasing markedly since the industrial revolution and is predicted to reach 500-1,000 ?mol mol(-1) by the end of this century. Although the short-term and acclimatory responses to elevated [CO(2)] have been well ...

Water relations in woody species are intimately related to xylem hydraulic properties. High CO(2) concentrations ([CO(2)]) generally decrease transpiration and stomatal conductance (g(s)), but there is little information about the effect of atmospheric [CO(2)] on xylem ...

Rising concentrations of atmospheric CO2 affect biotic and abiotic conditions in soil, which could alter the production and consumption of the important greenhouse gases N2O and CH4. Until now, the effect of elevated CO2 on N2O and CH4 fluxes from soil has not been quantitatively synthesized. ...

The carbon cycles for a sodium-cooled fast breeder are investigated. The equations of state are set up based upon the measured data available from publications. Three different types of cycles are proposed: a simple overcritical process with partial flow ...

We present the results of an extensive experimental study on the effects of hysteresis and wetting on permanent capillary trapping and relative permeability of CO2/brine systems. We performed 48 unsteady-state drainage and imbibition full-recirculation flow experiments in two different sandstone rock samples, i.e., Berea and Nugget. A state-of-the-art reservoir condition ...

The technology of supercritical CO2 fluid extraction for ginkgolic acids in the epicarp of Ginkgo biloba L. was studied. The effect of pressure, temperature and extraction time on the yield of the ginkgolic acids was explored. The optimum conditions for supercritical CO2 fluid extraction was 30 MPa, 45 degrees C, ...

This report presents detailed results for three flow problems involving CO2 migration in saline aquifers, that had been posed as part of an international code intercomparison study. Selected data for PVT properties of aqueous mixtures involving CO2 are given, and the dynamics of immiscible ...

of an effervescent material with water. The chemical reaction results in CO 2 bubbles ... effervescent material were conducted on the DC-9 aircraft ...

... Cardiac output, limb blood flow arterial pressure, heart rate, hematocrit, circulating histamine levels, O2 consumption, CO2 production, and ...

Jun 16, 2011 � Description: Development of reliable regional or global carbon budgets ... entered the cylinders through individually monitored flow meters. ...

... 3-13, 2002, scientists from four countries representing the Technical Committee of the International Carbon Dioxide Sequestration Experiment ...

... There are two types of lasers typically used for laser cutting applications. The most common type is the fast axial flow CO2 with pulsing capability. ...

... for both wavelengths and for seven materials. ... at 10.6 microns (CO2), the plasma ... SUBSONIC FLOW, CARBON DIOXIDE LASERS, LASER SPOTS ...

Data was compiled on H2O, CO2, S, and SO2 and it was analyzed by various techniques to prepare phase

... in reference [11 (transverse flow, discharge, CO2 ... that reexcitation of energy in the cavity ... in values between upper vibration energies which remain ...

... gas temperature was varied from ambient to 1680 F. A method was devised to estimate the capture coefficient of high-temperature CO2, and the ...

Experiments on CW transversely excited (TE) flowing CO2 gas mixtures are described. Several discharge and flow geometries at pressures up to 1 atm have been used to determine discharge properties in the channels used. Optical gain has not been measured in...

...imported, or exported through each flow meter in accordance with the procedures...of this section. If multiple flow meters are used, you shall calculate the annual mass of CO2 for all flow meters according to the procedures...

Mesquite is the dominant woody plant in floodplain environments of warm deserts in the southwestern US and thus plays a central role in biogeochemical cycling and energy exchange at landscape and potentially regional scales. Our project investigates the biotic and abiotic controls over seasonal dynamics of energy exchange, CO2 uptake ...

CAM requires a substantial investment of resources into storage carbohydrates to account for nocturnal CO(2) uptake, thereby restricting carbohydrate partitioning to other metabolic activities, including dark respiration, growth and acclimation to abiotic stress. Flexible modulation of carbon flow to the different ...

In this paper we apply CO2-PENS to characterize the long-term CO2 storage performance at SACROC, specifically with respect to potential impacts on ground water resources located above the CO2 injection depth. CO2-PENS is a hybrid process/system model composed of a library ...

Nodule CO2 fixation via PEPC provides malate for bacteroids and oxaloacetate for N assimilation. The process is therefore of central importance for efficient nitrogen fixation. Nodule CO2 fixation is known to depend on external CO2 concentration. The hypothesis of the ...

Understanding the processes involved in large-scale upward flow of CO2 related to Geologic Carbon Sequestration (GCS) is critical to evaluating trapping mechanisms and potential impacts of CO2 leakage over long distances. The Laboratory for Underground CO2 Investigations (LUCI) is being planned to be built at DUSEL to host large-scale ...

Studies have shown stomatal conductance (g(s)) of plants exposed to super-elevated CO2 (>5000micromol mol(-1)) increases in several species, in contrast to a decrease of g(s) caused by moderate CO2 enrichment. We conducted a series of experiments to determine whether super-elevated ...

CO2 storage in coal mines can offer a remarkable contribution to world-wide greenhouse gas control. Therefore, numerous technical approaches of CO2 storage in coal mines especially considering sorptive storage on residual coal seams have been developed within the last decade. The CO2 storage concept discussed here considers the utilization of mining ...

Increasing concentrations of atmospheric carbon dioxide (CO(2)) can affect biotic and abiotic conditions in soil, such as microbial activity and water content. In turn, these changes might be expected to alter the production and consumption of the important greenhouse gases nitrous oxide (N(2)O) and methane (CH(4)) (refs 2, 3). ...

Increasing concentrations of atmospheric carbon dioxide (CO2) can affect biotic and abiotic conditions in soil, such as microbial activity and water content. In turn, these changes might be expected to alter the production and consumption of the important greenhouse gases nitrous oxide (N2O) and methane (CH4) (refs 2, 3). However, ...

concentrations in the laboratory-based rate laws to compute continuum-scale reaction rates. To compare against RN in the field and use these concentrations directly in the laboratory-measured reaction rate laws to infer1 Up-Scaling Geochemical Reaction Rates Accompanying Acidic CO2-Saturated Brine Flow in Sandstone

Rapid hydroformylation of 1-octene (rates up to 800 h(-1)) with the catalyst remaining stable for at least 40 h and with very low rhodium leaching levels (0.5 ppm) is demonstrated when using a system involving flowing the substrate, reacting gases and products dissolved in supercritical CO(2) ...

Tests were conducted in an 8.25-in.-diam by 44.50-in. chamber utilizing 77 K walls to remove CO2 gas flow. The CO2 gas temperature was varied from ambient to 1680 F. A method was devised to estimate the capture coefficient of high-temperature CO2, and the...

whose flow rates are regulated by means of two Gilmont GF 1060 rotameters. A kd- Scientific 780 Gravimetric Analy zer (TGA) Steam Generator He water CO2 Rotameter N2 Rotameter Gases exit furnace InletL/min, with the syringe pump regulating the distilled water flow rate, and rotameters regulating the bone dry ...

The anthropogenic rise in atmospheric CO2 is expected to impact carbon fluxes not only at ecosystem level but also at the global scale by altering carbon cycle processes in soils. At the Swiss Canopy Crane (SCC), we examined how 7 years of free air CO2 enrichment (FACE) affected soil ...

A plausible model for the origin of the observed C-O-H volatiles observed in MORB glasses is that they were incorporated in primary melts of the upwelling mantle. Based on the observed ferric/ferrous ratios in MORB glass, it is probable that the MORB source mantle contained diamond or graphite, depending on pressure. If true, then during partial mantle melting the graphite/diamond would react ...

Life-history characteristics and functional traits of dominant organisms may interact with abiotic factors to shape ecosystem processes such as net primary productivity. For example, in terrestrial environments, physiographic position may interact with plant ontogeny to constrain ecosystem exchanges...

Alterations in biotic (i.e., water, nitrogen) and abiotic (i.e., light, temperature, [CO2], [O3]) conditions can significantly affect gas exchange properties of agronomic crops. Our objective was to elucidate mechanistic-based ecophysiological response of a broad range of agronomic crops to globa...

The carbon dioxide concentration [CO(2)], temperature and ultraviolet B radiation (UVB) are concomitant factors projected to change in the future environment, and their possible interactions are of significant interest to agriculture. The objectives of this study were to evaluate interactive effects of atmospheric ...

... 0.CO;2 Quantifying the Mass Balance of Ice Caps on Severnaya Zemlya, Russian High Arctic. II: Modeling the Flow of the Vavilov I...

... 2.0.CO;2 Leaf Degradation, Macroinvertebrate Shredders & Energy Flow in Streams: A Laboratory-Based Exercise Examining Ecosystem...

The effectiveness of various electronegative gases (O2, CO2, NO, SF6, H2O), as a means of reducing the ionization in plasma flow fields (nitrogen plasma) are experimentally investigated and compared. In the thermal condition prevailing, SF6 and water vapo...

A novel method to delay transition in hypervelocity flows in air over slender bodies by injecting CO2 into the boundary layer is presented. The dominant transition mechanism in hypersonic flow is the inviscid second (Mack) mode, which is associated with a...

A lab-scale seawater/mineral carbonate gas scrubber was found to remove up to 97% of CO2 in a simulated flue gas stream at ambient temperature and pressure, with a large fraction of this carbon ultimately converted to dissolved calcium bicarbonate. Contrary to predictions based on classical carbonate chemistry, up to 85% of the captured carbon was retained in solution, i.e., it did not degas or ...

Rising atmospheric carbon dioxide (CO(2)) concentration and air temperature are of major concern when considering the possible effects of global climate change on vegetations. Although production has been found to increase in many cases, other experiments have also indicated increased hazards for plant growth because of the increased frequency of weather ...

Several studies show rapid responses of soil CO2 efflux to infrequent precipitation events in arid ecosystems but the processes causing these rapid responses are not always clear. We measured soil CO2 efflux following irrigation events at the Mojave Global Change Facility near Las Vegas, NV. We measured total soil ...

... Flume runs with sand dollars were conducted in subcritical flow (ie, below the threshold for sand transport under abiotic conditions). RESULTS ...

Stem respiration rates are often quantified by measuring the CO(2) efflux from stems into chambers. It has been suggested that these measurements underestimate respiration because some of the respired CO(2) can be either retained or transported upwards in the transpiration stream. If the stem CO(2) efflux does not ...

Soil-gas monitoring is proposed for detecting CO2 leakage at geological CO2 sequestration sites. At the Cranfield oil field, about 25 km east of Natchez, Mississippi, an integrated near-surface monitoring program is being implemented where supercritical CO2 is being ...

We investigate the physical processes that occur during the sequestration of carbon dioxide (CO2) in liquid-saturated, brine-bearing geologic formations using the numerical simulator TOUGH2. CO2 is injected in a supercritical state that has a much lower density and viscosity than the liquid brine it displaces. In ...

The internal stress and microstructure of ZnO films were investigated as a function of carbon dioxide (CO2) gas flow ratio [CO2/(O2+CO2)] during sputter deposition. The internal stress of the ZnO films decreased with increasing ...

Quantification of the effect of microorganisms and associated organic ligands on mineral dissolution rate is one among the last remaining challenges in modeling of water-rock interactions under earth surface and subsurface environments. This is especially true for deep underground settings within the context of CO2 capture, sequestration and storage. First, elevated ...

To assess how microbial processing of organic C inputs to forest soils may be influenced by elevated CO2 and altered N dynamics, we followed the fate of 13C-labeled substrates in soils from the Duke Free Air Carbon Enrichment site where differences in soil N status have been imposed by 7 years of N amendments. Heterotrophic respiration and ?13C of respired ...

Soil gas transport in fault zones has implications for a broad range of studies, including seismotectonics, volcano monitoring, natural resource exploration, and environmental contamination problems. We evaluate soil gas transport along the San Andreas fault (SAF) in Parkfield, CA from the perspective of both field observations and numerical modeling. CO2 ...

Effects of the shape of the supersonic nozzle, which is one of CO2 gasdynamic laser (CO2GDL) components, on combustion-driven CO2GDL performance are investigated by numerical simulations of 2D compressible viscous vibrational nonequilibrium nozzle flow. The performance should be estimated with ...

Projections of climate change impacts on global food supply are largely based on crop and pasture modelling. The consistency of these models with experimental data and their ability to simulate the effects of elevated CO(2) and of increased climate variability has been debated. The effects of high temperatures, of increased climate variability and of ...

Oxides and silicates which crystallize in the presence of H2O, CO2 and N2, especially at high pressures, are expected to dissolve traces of these fluid components. In doing so atomic and electronic rearrangements occur between the host lattice and the dissolved molecules which lead to different solute species. These may be simply hydroxyl OH-, carbonate ...

Injection of supercritical carbon dioxide, CO2, into deep saline aquifers and other formations during geologic CO2 sequestration, can result in complex fluid-rock reactions, potentially mitigated by biological processes. Such reactions may result in mineral dissolution or precipitation that in turn can modify fluid ...

The current trends and principles of gas flow lasers, chemical lasers, and electrically excited supersonic lasers are reviewed with an emphasis on gas dynamic lasers. The principles, aeodynamics and characteristics of 16- and 9-micron CO2 gasdynamic lasers are analyzed. The performance characteristics of supersonic ...

Developing technologies to reduce the rate of increase of atmospheric concentration of carbon dioxide (CO2) from annual emissions of 8.6PgCyr-1 from energy, process industry, land-use conversion and soil cultivation is an important issue of the twenty-first century. Of the three options of reducing the global energy use, developing low or no-carbon fuel ...

A fractured sandstone aquifer at an industrial site in southern California is contaminated with trichloroethene (TCE) and cis-1,2-dichloroethene (cis-DCE) to depths in excess of 244 m. Field monitoring data suggest that TCE is undergoing reduction to cis-DCE and that additional attenuation is occurring. However, vinyl chloride (VC) and ethene have not been detected in significant amounts, so that ...

Human activities have resulted in increased nitrogen deposition and atmospheric CO(2) concentrations in the biosphere, potentially causing significant changes in many ecological processes. In addition to these ongoing perturbations of the abiotic environment, human-induced losses of biodiversity are also of major concern and may ...

Leakage of CO2 from a geologic storage reservoir along an idealized fault zone has been simulated, including transitions between supercritical, liquid, and gaseous CO2. We find strong non-isothermal effects and nonmonotonic leakage behavior, due to an interplay between multiphase flow and heat transfer effects.

Equilibrium thermodynamic and flow properties are presented in tabulated and graphical form for moving, standing, and reflected normal shock waves in pure CO2, representative of Mars and Venus atmospheres. Properties include pressure, temperature, density...

A sealed-off transversely excited atmosphere CO2 laser with a gas internal coaxial circulation scheme is presented. Long-lived (10(exp 6) shots) stable glow discharges at a pulse repetition frequency up to 33 Hz are demonstrated. The minimum clear ratio is found to be smaller than Dzakowic's theoretical limit.

The performance of an alumina-supported Pt catalyst system used to maintain the gas purity in an electron-beam-sustained (636) isotope CO2 laser amplifier has been tested. The system characteristics using the two-zone, parallel flow reactor were determine...

A concept has been developed for a carbon dioxide laser with high power per unit length or volume based on the transverse-flow principle with convection cooling and transverse discharge. The design and construction of a laser module which can be used as a...

The report describes one study which contributed to the construction of the Monts d'Arree nuclear power station: EL 4. The reactor is cooled by a CO2 current provided by 3 turbo-blower groups. The priming vapour for the turbines is taken at the exit of th...

This report describes one study which contributed to the construction of the Monts d'Arree nuclear power station : EL 4. The reactor is cooled by a CO2 current provided by 3 turbo-blower groups. The priming vapour for the turbines is taken at the exit of ...

A carbon dioxide laser was improved by reduction of focus radius and appropriate beam modulation giving higher power densities in focus. Modulation of the resonator and of the power exciter enable the realization of a 1 kW system with one discharge tube a...

The SOCRATES contamination-interaction code has been used to simulate the reactions of O + CO2 --> CO2(v) + O, O + CO2 - CO(v) + O2, and CO2 + H - CO + OH(v) at an altitude of 800 km in both ram and wake directions of the spacecraft. These simulations show that the ...

The possibility of realizing a high power CO2 laser using an independent electric discharge to generate molecular vibrations in a supersonic CO2 laser gas mixture was investigated. The supersonic flow is produced by air blasts from a wind tunnel nozzle al...

During the past decade, substantial investments were made in the development of gas discharge pumped CO2 lasers for military and civilian applications. Compact, lightweight CO2 lasers for airborne and spaced based radar applications directed toward target ranging, imaging, and discrimination are discussed. These ...

Serpentinization within subduction zones may generate reduced fluids that contain higher concentrations of abiotic methane than near-surface ultramafic environments. We present preliminary experimental data suggesting that the kinetics of abiotic methanogenesis are enhanced at high pressures. Thermodynamic calculations of C-O-H fluid speciations at the low ...

The decomposition of litter is an important ecosystem function that controls carbon and nutrient cycling, which is well understood from the relationship between temperature and moisture. However, the decomposition in the arid and semiarid environments (hereafter drylands) is relatively poorly predicted due to several abiotic factors such as the effect of ultraviolet radiation ...

The dynamics of steady state catalytic methanol oxidation on a polycrystalline Pt surface over a range of surface temperatures and reactant flow conditions were investigated by monitoring the kinetics with mass spectrometry and the internal state distribution of nascent CO(2) with tunable diode laser absorption spectroscopy. The ...

Stabilizing the concentration of atmospheric CO(2) may require storing enormous quantities of captured anthropogenic CO(2) in near-permanent geologic reservoirs. Because of the subsurface temperature profile of terrestrial storage sites, CO(2) stored in these reservoirs is ...

In the present work the thermogravimetric characterization of the sorption of carbon dioxide on polymer-modifiedmesoporous materials (MCM-41) from fly ashes is described. In order to obtain MCM-41 materials from three different types fly ashes,(including CFB fly ash) hydrothermal processesusing the supernatantsof coal fly ashes and surfactantsas the structure-directing agents,have been carried ...

Photosynthetic CO(2) and O(2) exchange was studied in two moss species, Hypnum cupressiforme Hedw. and Dicranum scoparium Hedw. Most experiments were made during steady state of photosynthesis, using (18)O(2) to trace O(2) uptake. In standard experimental conditions (photoperiod 12 h, 135 micromoles photons per square meter per second, 18 degrees C, 330 ...

A numerical model of the folded resonator is founded by using the eigenvector method. The beam characteristics and relative amplitude distribution of dominant mode of the N-shaped three-folded resonator with different aperture diameter are obtained by numerical simulation. The experiment of the resonator is done on HUST5000 high power transverse flow ...

The availability of lasers providing a higher power leads to an extension of the range of laser applications in the area of material processing. However, possibilities regarding an enhancement of specific laser power by means of the specific input power are limited because of the occurrence of instabilities in the discharge plasma. An investigation is conducted regarding the aproaches which could ...

We report here, for the first time, evolution of the streaming potential coupling coefficient as liquid carbon dioxide infiltrates Berea sandstone. Using 125 Omega-m tap water, the coupling coefficient determined before and after each CO2 flood of five samples averaged approximately -30 mV/0.1 MPa. After liquid CO2 ...

Mefite d'Ansanto, southern Apennines, Italy is the largest natural emission of low temperature CO2 rich gases, from non-volcanic environment, ever measured in the Earth. The emission is fed by a buried reservoir, made up of permeable limestones and covered by clayey sediments. We estimated a total gas flux of �2000 tons per day. Under low wind ...

A facility has been constructed to perform controlled shallow releases of CO2 at flow rates that challenge near surface detection techniques and can be scalable to desired retention rates of large scale CO2 storage projects. Preinjection measurements were made to determine background conditions and characterize natural variability at ...

Researchers derived a quantitative relationship between the effectiveness of an atmospheric greenhouse and internal heat flow in producing the morphological differences between earlier and later Martian terrains. The derivation is based on relationships previously derived by other researchers. The reasoning may be stated as follows: the CO2 mean residence time in the Martian ...

In spite of the importance of respiration in forest carbon budgets, the mechanisms by which physiological factors control stem respiration are unclear. An experiment was set up in a Eucalyptus globulus plantation in central Portugal with monoculture stands of 5-year-old and 10-year-old trees. CO(2) efflux from stems under shaded and unshaded conditions, as ...

Soils release more carbon per annum than current global anthropogenic emissions (Luo and Zhou, 2006). Soils emit carbon dioxide through mineralization and decomposition of organic matter and respiration of roots and soil organism (Houghton 2007) Evaluation of the effects of abiotic factors on microbial activity is of major importance in the context of mitigation greenhouse ...

This Science Object is the second of four Science Objects in the Coral Reef Ecosystems SciPack. It investigates the abiotic characteristics that affect the coral reef ecosystem. The number and kinds of organisms found along each reef depend on the physical conditions of the environment and resources available, including food, light, water quality, temperature, and other ...

Abiotic stresses, such as drought and salinity, lead to crop growth damage and a decrease in crop yields. Stomata control CO(2) uptake and optimize water use efficiency, thereby playing crucial roles in abiotic stress tolerance. Hydrogen peroxide (H(2)O(2)) is an important signal molecule that induces stomatal ...

When CO2 is injected down a well, the temperature at the bottom of the well depends on surface conditions, heat exchange with the wall of the well and pressure work within the well. Typically, the temperature of the CO2 at the bottom of the well is lower than the local geothermal temperature. As this relatively cold ...

Carbon dioxide (CO2) sequestration in geologic formations is the most direct carbon management strategy for long-term removal of anthropogenic CO2 from the atmosphere, and is likely to be needed for continuation of the US fossil fuel-based economy and high standard of living. Subsurface injection of CO2 into ...

We examined the effects of repeated artificial CO(2) (1,000 ppm) bathing on tympanic temperature (T(ty)), cutaneous blood flow, and thermal sensation in six healthy males. Each subject was immersed in CO(2)-rich water at a temperature of 34 degrees C up to the level of the diaphragm for 20 min. The CO(2)-rich water was prepared using a ...

Stomatal opening in plant leaves control carbon and water exchange between vegetation and the atmosphere. Closure of these water-gates in response to increased atmospheric CO2 mixing ratio's, reduces transpiration under most laboratory and short term experimental conditions. Does this imply however, as atmospheric ...

Amorphous SiOxNy films were deposited by pulsed-dc reactive magnetron sputtering using a boron-doped Si target under Ar--CO2--N2 atmosphere. The refractive index (n) varied continuously between 1.54 and 2.0 with the CO2 flow ratio [CO2/(CO2+ N2)], ...

The performance of a high-power fast-axial-flow CO2 laser is directly determined by the characteristics of the turbulent flow of the active medium in the discharge region. To research the influence of the discharge tube structure on the internal gas flow field and determine the optimum design ...

Multiphase flow induced CO2 corrosion has resulted in serious losses in oil and gas production. In this paper, gas-liquid two-phase vertical upward slug flow has been analyzed from aspects containing flow structure, hydrodynamic characteristics, mass transfer characteristics and their effects ...

Geological carbon capture and storage, in which compressed CO2 is injected into deep saline aquifers for permanent storage, forms an integral part of CO2 mitigation strategies. At representative reservoir conditions CO2 is buoyant and may therefore leak into surface waters or the atmosphere. The leakage of CO2 back ...

PURPOSE: The choice of minimally invasive surgical approaches in pediatric urology is largely influenced by surgeon preference and experience. Little is known about the differences in physiological variables that might objectively influence the choice of surgical approach. We compared the cerebral and systemic hemodynamic effects of transperitoneal vs retroperitoneal ...

ice, snow melt, CO2 aquifers, and dry debris flow. Observational tests have been conducted using remote sensing data gathered by three ...

How do carbon and other elements transition between ocean pools and pass through the ... Sea and Arctic carbon chemistry, including ocean acidification and air/ sea CO2 flux? ... mixed layer flow carbon balance studies, trace metals, POC ...

A new technique to delay transition to turbulence in hypervelocity air flows is introduced and investigated in this work. The main motivation for such a technique is the pressing need to reduce aerodynamic heating rates on hypersonic vehicles. Turbulent h...

Fluid flow through rock fractures can be orders of magnitude faster than through the adjacent low-permeability rock. Understanding how fluid moves through these pathways is important for the prediction of sequestered CO2 transport in geologic reservoirs. ...

into the Fundamental Processes Governing CO2 Storage in Virgin Seams and in Coal Seams Stimulated by Underground Coal Gasification � A. Modelling of the Flow Behaviour of Gas in UCG Stimulated Coalbeds to predict the induced

... 83 4.3 Reduced Smoke Propellant (H20, CO2 , CO, HCf/ZrO2 ) Plum e ..... 103 5. SUMMARY AND CONCLUSIONS ..... ...

... sured using calibrated mass flow meters (Teledyne-Has- ... of N, was used to purge the region between the ... 10 ns2" and the kinetic decays occur on ...

Jul 16, 2008 ... pressure drop, as well as a new process flow control valve that ... Humans also exhale water vapor and exchange water vapor with the .... CO2 analysis was provided both upstream and downstream of the CAMRAS by external ...

CO2 and H20. The Flow of Matter. Oxygen,. Oxidation and. Combustion. Stratospheric. Ozone ... by the ozone layer. CFC molecules are able to migrate intact up into the ... depletion means more than just the natural destruction of ozone. ...

Optimization of CO2 gas turbine secondary loops connected to sodium cooled fast breeder reactors requires a simple supercritical thermodynamic or condensation regime with partial flow compression as well as high turbine inlet temperatures.

The paper reports the results obtained with an arc-driven gas dynamic laser (GDL) having an aerodynamic nozzle designed so that cold CO2 or other gases can be injected either into the expanding N2 flow before it reaches the nozzle exit (supersonic mixing ...

We hypothesized that changes in plant growth resulting from atmospheric CO2 and O3 enrichment would alter the flow of C through soil food webs and that ... ...

Explore the role of aircraft emissions of NOx, soot particles, CO2, SO2 and H2O .... At somewhat higher altitudes (700 mb, a bit over 3 km, not shown), flows are ...

Within this project, the heat transfer and pressure drop characteristics of CO2 (R-744) were investigated at supercritical pressures (cooling) and subcritical pressures (evaporation). The measurements were carried out with a microchannel type (MPE) tube w...

... temperature fast-flow reactor (HTFFR) which, in ... the 300-2000 K temperature range. ... CARBON DIOXIDE, *FAST REACTORS, HIGH TEMPERATURE ...

als have suggested that the flows were caused by: seepage from groundwater exfiltration, melt-water from ice-rich mantle deposits, gaseous CO2 release, or ...

Erosion of the Martian surface by the flow of liquid water has apparently taken place at different times and locations on the planet. Many attempts were made to explain the valley networks by invoking a strong atmospheric CO2/H2O greenhouse early in the h...

laser will enable the measurement of wind, CO2, aerosols, clouds, and river flow . LaRC is the world leader in high pulse-energy 2-micron laser technology. ...

Understanding core scale and pore scale migration of CO2 will improve our ability to predict storage capacity and determine the effectiveness of solubility and capillary (residual CO2) trapping. While the theoretical underpinnings of multi-phase flow are ...

Modified atmosphere packaging (MAP) using carbon dioxide to replace or partially replace the air surrounding the fresh product is used to extend the shelf-life of certain foods. CO2 is believed to delay the onset of spoilage in fresh muscle foods due to t...

. These investigations were conducted at 293 K within a slow flow reactor at about 4 Torr coupled to a multiplexed cylinders (Matheson Trigas) and were found to be stable for weeks. The purity of the bromoacetylene sample

projects that have focused on computing techniques to simulate multi-component and multiphase fluid flow in the fields of nuclear waste disposal, CO2 geologic sequestration,...

stall control, blade clearance control, combustion control, ... shape memory alloy. UEET. = Ultra-Efficient Engine Technology .... and dynamic), surface and gas; mass flow, surface strain, and blade tip clearance sensors. ...

The objective of this project was to assess the feasibility of using a membrane process to capture CO2 from coal-fired power plant flue gas. During this program, MTR developed a novel membrane (Polaris�) with a CO2 permeance tenfold higher than commercial CO2-selective membranes used in natural gas treatment. ...

Typically, animal pollinators are attracted to flowers by sensory stimuli in the form of pigments, volatiles, and cuticular substances (hairs, waxes) derived from plant secondary metabolism. Few studies have addressed the extent to which primary plant metabolites, such as respiratory carbon dioxide (CO(2)), may function as pollinator attractants. ...

Recent breakthroughs in CO(2) fumigation methods using free-air CO(2) enrichment (FACE) technology have prompted comparisons between FACE experiments and enclosure studies with respect to quantification of the effects of projected atmospheric CO(2) concentrations on crop yields. On the basis of one such comparison, ...

The concentration of 18O in atmospheric CO2 and H2O is a potentially powerful tracer of ecosystem carbon and water fluxes. In this paper we describe the development of an isotope model (ISOLSM) that simulates the 18O content of canopy water vapor, leaf water, and vertically resolved soil water; leaf photosynthetic 18OC16O (hereafter C18OO) fluxes; ...

The concentration of 18O in atmospheric CO2 and H2O is a potentially powerful tracer of ecosystem carbon and water fluxes. In this paper we describe the development of an isotope model (ISOLSM) that simulates the 18O content of canopy water vapor, leaf water, and vertically resolved soil water; leaf photosynthetic 18OC16O (hereinafter C18OO) fluxes; ...

A novel method to delay transition in hypervelocity flows in air over slender bodies by injecting CO2 into the boundary layer is demonstrated and investigated. Experimental data were obtained in Caltech's T5 reflected shock tunnel. The experimental model was a 5 degree half-angle sharp cone instrumented with thermocouples, providing ...

Leakage of CO2 from a hypothetical geologic storage reservoir along an idealized fault zone has been simulated, including transitions between supercritical, liquid, and gaseous CO2. We find strong non-isothermal effects due to boiling and Joule-Thomson cooling of expanding CO2. Leakage fluxes are limited by ...

A CW glow discharge exciting a subsonic, transverse-flow CO2 laser was stabilized by means of a CW auxiliary discharge. The stabilizing discharge was maintained between an array of individually ballasted anodes and the cathode of the main discharge. With a simple electrode configuration an extension of stable glow to higher gas ...

Solvent extracted cashew nut shell liquid (CNSL), conventionally known as natural CNSL, is a mixture of several alkenyl phenols. One of these alkenyl phenols is anacardic acid, which is present at the highest concentration. In view of anticipated industrial applications of anacardic acid, the objective of this work was to isolate anacardic acid from natural CNSL by supercritical carbon dioxide ...

Carbon dioxide (CO2) sequestration in deep saline aquifers and exhausted oil fields has been widely considered as a means for reducing CO2 emissions to the atmosphere as a counter-measure to global warming. However, rather than treating CO2 as a waste fluid in need of ...

We present a novel technique in which the carbon isotope ratio (delta(13)C) of soil CO(2) is measured from small gas samples (<5 mL) injected into a stream of CO(2)-free air flowing into a tunable diode laser absorption spectrometer (TDL). This new method extends the dynamic range of the TDL to measure ...

Plant volatiles are the metabolites that plants release into the air. The quantities released are not trivial. Almost one-fifth of the atmospheric CO2 fixed by land plants is released back into the air each day as volatiles. Plants are champion synthetic chemists; they take advantage of their anabolic prowess to produce volatiles, which they use to protect ...

Hydrological and geochemical monitoring are key components of site characterization and CO2 plume monitoring for a pilot test to inject CO2 into a brine-bearing sand of the fluvial-deltaic Frio formation in the upper Texas Gulf Coast. In situ, injected CO2 forms a supercritical phase that has gas-like properties ...

Hydrochemical conditions characteristic of kerogen-rich geopressured sediments contribute to the development of a predictable alteration mineralogy. The following conditions result in the geopressured fluid becoming enriched, and in some cases, saturated with CO 2 and CH 4 : 1. (1) the upward and generally restricted flow of fluids in ...

The formation of organic compounds during the decomposition of iron oxalate dihydrate (IOD) was investigated as a possible analog for abiotic organic synthesis in geological systems. After heating at 330 degrees C for 2-4 days, IOD decomposed to a mixture of the minerals siderite and magnetite plus gas and non-volatile organic compounds. The organic products included an ...

Dissolved oxygen (DO) concentration is often one of the major determinants of the geochemistry and microbiology of shallow aquifer systems. DO is often consumed along groundwater flow paths but, the processes that use DO (e.g., biological or inorganic) are often unclear. The use of stable isotopes of molecular O2 (?18O-DO) in conjunction with the stable isotope composition of ...

Trunk CO2 efflux is a major component of total CO2 forest ecosystem efflux but its determinism is still poorly understood. This CO2 flux could originate from different carbon sources (respiration of newly assimilates or reserves; xylem sap flow dissolved ...

We investigated the potential for abiotic mineralization to carbon dioxide (CO2) via photodegradation to account for carbon (C) loss from plant litter under conditions typical of arid ecosystems. We exposed five species of grass and oak litter collected from arid and mesic sites to a factorial design of ultraviolet (UV) radiation (UV ...

Thermodynamic calculations of metastable equilibria were used to evaluate the potential for abiotic synthesis of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in the martian meteorite Allan Hills (ALH) 84001. The calculations show that PAHs and normal alkanes could form metastably from CO, CO2, and H2 below approximately ...

Thermodynamic calculations of metastable equilibria were used to evaluate the potential for abiotic synthesis of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in the martian meteorite ALH 84001. The calculations show that PAHs and normal alkanes could form metastably from CO, CO2, and H2 below ~250-300 deg C during rapid ...

Oxygen convective uptakes in gas exchange cycles were directly recorded in early diapause pupae of Pieris brassicae L. (Lepidoptera; Pieridae) by means of O(2) coulometric respirometry. This method was combined with flow-through CO(2) respirometry, the two systems being switchable one to the other. During recording with both systems, ...

Typical geologic carbon sequestration scenarios involve the injection of supercritical CO2 into an aquifer while displacing brine in what is equivalent to a water drainage process. Due to density differences, the CO2 will tend to buoyantly migrate upward until an impermeable barrier is encountered. This buoyant CO2 ...

The concurrent measurement of self-potential (SP) and soil CO{sub 2} flux (F{sub s}{sup CO2}) in volcanic systems may be an important tool to monitor intrusive activity and understand interaction between magmatic and groundwater systems. However, quantitative relationships between these parameters must be established to apply them toward understanding ...

We are investigating the technical feasibility of injecting CO2 for carbon sequestration with enhanced gas recovery (CSEGR) in the depleted Altmark natural gas reservoir, Germany. Our approach is numerical simulation using TOUGH2/EOS7C. Our earlier simulation studies have shown early CO2 breakthrough due to ...

Anatomic features of carotid artery stenosis, as defined angiographically, do not necessarily correlate with the hemodynamic significance of the narrowing. The concept of regional cerebral vasodilatory (or perfusion) reserve has been advocated as a means of defining the hemodynamic compromise associated with carotid lesions. We evaluated the feasibility of using SPECT imaging with 5% ...

There is now increasing evidence from the experimental and clinical setting that therapeutic hypercapnia from intentionally inspired carbon dioxide (CO(2)) or lower tidal volume might be a beneficial adjunct to the strategies of mechanical ventilation in critical illness. Although previous reports indicate that CO(2) exerts a beneficial effect in the ...

The paper presents results of a numerical simulation of a supersonic two-dimensional (2D) viscous flow containing CO2 molecules near a spacecraft entering the Mars atmosphere. The gas-dynamic equations in the shock layer are coupled to the equations of non-equilibrium vibrational and chemical kinetics in the five-component mixture ...

A microporous membrane oxygenator has been used in 258 clinical perfusions for cardiac surgery. In 132 perfusions the oxygenator was ventilated with 100% O2, and in 126 perfusions 98% O2-2%CO2 was used. Patients' BSA was 0.4-2.3 M2. Bypass duration was up to 563 min. In the group ventilated with 100% O2, average ...

Regional arterial CO2 tension (PaCO2) reactivity of cerebral blood flow (CBF) and the effect of PaCO2 on the spatial and temporal heterogeneity of CBF were investigated by using autoradiographically determined CBF in the rat middle cerebral artery occlusion model after a 2-h period under ...

Understanding the effects of coupled surface and subsurface fluid flow can help measurement, monitoring and verification (MM&V) operators to better develop work plans at potential sequestration sites. Seepage of carbon dioxide (CO2) from beneath Mammoth Mountain, CA is a natural analogue for researchers interested in developing ...

Reduced stomatal conductance under elevated CO2 results in increased soil moisture, provided all other factors remain constant. Whether this results in increased runoff critically depends on the interaction of rainfall patterns, soil water storage capacity and plant responses. To test the sensitivity of runoff to these parameters under elevated ...

In Nova Scotia, constructed wetland systems are widely considered as effective treatment systems for agricultural wastewater. Although research has examined the water quality treatment attributes, there has been limited focus on the air quality effects of these systems. Six operational pilot-scale constructed wetlands were built with flow-through chambers for quantifying ...