bluuebunny/crossref_metadata_2025 huggingface dataset:
Humor Therapy: Relieving Chronic Pain and Enhancing Happiness for Older Adults
Authors: Tse Mimi M. Y. , Lo Anna P. K. , Cheng Tracy L. Y. , Chan Eva K. K. , Chan Annie H. Y. , Chung Helena S. W.
Published: June 2010

The present study examined the effectiveness of a humor therapy program in relieving chronic pain, enhancing happiness and life satisfaction, and reducing loneliness among older persons with chronic pain. It was a quasiexperimental pretest-posttest controlled design. Older persons in a nursing home were invited to join an 8-week humor therapy program (experimental group), while those in another nursing home were treated as a control group and were not offered the program. There were 36 older people in the experimental group and 34 in the control group. Upon completion of the humor therapy program, there were significant decreases in pain and perception of loneliness, and significant increases in happiness and life satisfaction for the experimental group, but not for the control group. The use of humor therapy appears to be an effective nonpharmacological intervention. Nurses and other healthcare professionals could incorporate humor in caring for their patients.
Process Design and Economics of On-Site Cellulase Production on Various Carbon Sources in a Softwood-Based Ethanol Plant
Authors: Barta Zsolt , Kovacs Krisztina , Reczey Kati , Zacchi Guido
Published: June 2010

On-site cellulase enzyme fermentation in a softwood-to-ethanol process, based on SO2-catalysed steam pretreatment followed by simultaneous saccharification and fermentation, was investigated from a techno-economic aspect using Aspen Plus© and Aspen Icarus Process Evaluator© softwares. The effect of varying the carbon source of enzyme fermentation, at constant protein and mycelium yields, was monitored through the whole process. Enzyme production step decreased the overall ethanol yield (270 L/dry tonne of raw material in the case of purchased enzymes) by 5–16 L/tonne. Capital cost was found to be the main cost contributor to enzyme fermentation, constituting to 60–78% of the enzyme production cost, which was in the range of 0.42–0.53 SEK/L ethanol. The lowest minimum ethanol selling prices (4.71 and 4.82 SEK/L) were obtained in those scenarios, where pretreated liquid fraction supplemented with molasses was used as carbon source. In some scenarios, on-site enzyme fermentation was found to be a feasible alternative.
Innovative telemonitoring system for cardiology: from science to routine operation
Authors: Morak J. , Modre R. , Kollmann A. , Ebner C. , Fruhwald FM. , Schreier G. , Kastner P.
Published: June 2010

Objective: Results of the Austrian MOBITEL (MOBIle phone based TELemonitoring for heart failure patients) trial indicate that home-based telemonitoring improves outcome of chronic heart failure (CHF) patients and reduces both frequency and duration of hospitalizations. Based on lessons learned, we assessed the weak points to clear the way for routine operations.

Methods: We analyzed the system with respect to recommendations of the ESC Guidelines and experiences gained throughout the trial to identify potential improvements. The following components have been identified: a patient terminal with highest usability, integrated way to document drug-intake and well-being, and automated event detection for worsening of CHF. As a consequence the system was extended by Near Field Communication (NFC) technology and by an event management tool.

Results: Usability evaluation with 30 adults (14f, median 51y. IQR[45-65]) showed that 21 (8f) were able to immediately operate the system after reading a step-by-step manual. Eight (6f) needed one time demonstration and one man (80y) failed to operate the blood pressure meter. Routine operation of the revised system started in March 2009. Within 9 months, 15 patients (4f, median 74y. IQR[71-83], all NYHA-III) transmitted 17,149 items. 43 events were detected because of body weight gain of more then 2kg within 2 days. 49 therapy adjustments were documented. Three patients stopped using the system, two (1f) because of non-compliance and one (m, 82y) because of death. Overall, the rate of adherence to daily data transfer was 78%.

Conclusion: First results confirm the applicability of the revised telemonitoring system in routine operation.

Citation: Kastner P, MorakJ, Modre R, Kollmann A, Ebner C, Fruhwald FM, Schreier G. Innovative telemonitoring system for cardiology: from science to routine operation. Appl Clin Inf 2010; 1: 165–176 http://dx.doi.org/10.4338/ACI-2009-12-RA-0021
Hygroscopic properties of Amazonian biomass burning and European background HULIS and investigation of their effects on surface tension with two models linking H-TDMA to CCNC data
Authors: Fors E. O. , Rissler J. , Massling A. , Svenningsson B. , Andreae M. O. , Dusek U. , Frank G. P. , Hoffer A. , Bilde M. , Kiss G. , Janitsek S. , Henning S. , Facchini M. C. , Decesari S. , Swietlicki E.
Published: June 2010

Abstract. HUmic-LIke Substances (HULIS) have been identified as major contributors to the organic carbon in atmospheric aerosol. The term "HULIS" is used to describe the organic material found in aerosol particles that resembles the humic organic material in rivers and sea water and in soils. In this study, two sets of filter samples from atmospheric aerosols were collected at different sites. One set of samples was collected at the K-puszta rural site in Hungary, about 80 km SE of Budapest, and a second was collected at a site in Rondônia, Amazonia, Brazil, during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia – Smoke Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC) biomass burning season experiment. HULIS were extracted from the samples and their hygroscopic properties were studied using a Hygroscopicity Tandem Differential Mobility Analyzer (H-TDMA) at relative humidity (RH) <100%, and a cloud condensation nucleus counter (CCNC) at RH >100%. The H-TDMA measurements were carried out at a dry diameter of 100 nm and for RH ranging from 30 to 98%. At 90% RH the HULIS samples showed diameter growth factors between 1.04 and 1.07, reaching values of 1.4 at 98% RH. The cloud nucleating properties of the two sets of aerosol samples were analysed using two types of thermal static cloud condensation nucleus counters. Two different parameterization models were applied to investigate the potential effect of HULIS surface activity, both yielding similar results. For the K-puszta winter HULIS sample, the surface tension at the point of activation was estimated to be lowered by between 34% (47.7 mN/m) and 31% (50.3 mN/m) for dry sizes between 50 and 120 nm in comparison to pure water. A moderate lowering was also observed for the entire water soluble aerosol sample, including both organic and inorganic compounds, where the surface tension was decreased by between 2% (71.2 mN/m) and 13% (63.3 mN/m).
Quantifying immediate radiative forcing by black carbon and organic matter with the Specific Forcing Pulse
Authors: Bond T. C. , Zarzycki C. , Flanner M. G. , Koch D. M.
Published: June 2010

Abstract. We propose a measure to quantify climate warming or cooling by pollutants with atmospheric lifetimes of less than one year: the Specific Forcing Pulse (SFP). SFP is the amount of energy added to the Earth system per mass of pollutant emitted. Global average SFP for black carbon, including atmosphere and cryosphere, is 1.12 GJ g−1 and that for organic matter is −0.061 GJ g−1. We provide regional values for black carbon (BC) and organic matter (OM) emitted from 23 source-region combinations, divided between atmosphere and cryosphere impacts and identifying forcing by latitude. Regional SFP varies by about 40% for black carbon. This variation is relatively small because of compensating effects; particles from regions that affect ice albedo typically have shorter atmospheric lifetimes because of lower convection. The ratio between BC and OM SFP implies that, for direct forcing, an OM:BC mass ratio of 15 has a neutral effect on top-of-atmosphere direct forcing for any region, and any lower ratio induces direct warming. However, important processes, particularly cloud changes that tend toward cooling, have not been included here. We demonstrate ensemble adjustment, in which we produce a "best estimate" by combining a suite of diverse but simple models and enhanced models of greater complexity. Adjustments for black carbon internal mixing and for regional variability are discussed; regions with convection are implicated in greater model diversity. SFP expresses scientific uncertainty and separates it from policy uncertainty; the latter is caused by disagreements about the relevant time horizon, impact, or spatial scale of interest. However, metrics used in policy discussions, such as global warming potentials, are easily derived from SFP. Global-average SFP for biofuel and fossil fuel emissions translates to a 100-year GWP of about 760 for black carbon and −40 for organic matter when snow forcing is included. Ensemble-adjusted estimates of atmospheric radiative impact by black and organic matter using year 2000 emissions are +0.46 W m−2 and −0.17 W m−2, respectively; anthropogenic forcing is +0.38 W m−2 and −0.12 W m−2. The black carbon value is only 11% higher than that of the Intergovernmental Panel on Climate Change (IPCC), although this value includes enhanced absorption due to internal mixing.
Present and future impact of aircraft, road traffic and shipping emissions on global tropospheric ozone
Authors: Koffi B. , Szopa S. , Cozic A. , Hauglustaine D. , van Velthoven P.
Published: June 2010

Abstract. In this study, the LMDz-INCA climate-chemistry model and up-to-date global emission inventories are used to investigate the "present" (2000) and future (2050) impacts of transport emissions (road traffic, shipping and aircraft) on global tropospheric ozone. For the first time, both impacts of emissions and climate changes on transport-induced ozone are investigated. The 2000 transport emissions are shown to mainly affect ozone in the Northern Hemisphere, with a maximum increase of the tropospheric column of up to 5 DU, from the South-Eastern US to Central Europe. The impact is dominated by road traffic in the middle and upper troposphere, north of 40° S, and by shipping in the northern lower troposphere, over oceanic regions. A strong reduction of road emissions and amoderate (B1 scenario) to high (A1B scenario) increase of the ship and aircraft emissions are expected by the year 2050. As a consequence, LMDz-INCA simulations predict a drastic decrease in the impact of road emissions, whereas aviation would become the major transport perturbation on tropospheric ozone, even in the case of avery optimistic aircraft mitigation scenario. The A1B emission scenario leads to an increase of the impact of transport on zonal mean ozone concentrations in 2050 by up to +30% and +50%, in the Northern and Southern Hemispheres, respectively. Despite asimilar total amount of global NOx emissions by the various transport sectors compared to 2000, the overall impact on the tropospheric ozone column is increased everywhere in 2050, due to a sectoral shift in the emissions of the respective transport modes. On the opposite, the B1 mitigation scenario leads to asignificant reduction (by roughly 50%) of the ozone perturbation throughout the troposphere compared to 2000. Considering climate change, and according to scenario A1B, a decrease of the O3 tropospheric burden is simulated by 2050 due to climate change (−1.2%), whereas an increase of ozone of up to 2% is calculated in the upper troposphere in the inter-tropical zone, due to enhanced lightning activity. A global impact of similar magnitude is simulated for the transport-induced ozone burden perturbation (−1.6%). As a result, the future increase in global ozone due to changes in anthropogenic emissions is lowered by 12% and by 4%, for the background and the transport-induced ozone, respectively. However, positive and negative climate effects are obtained on ozone, depending on the season, region and altitude, with an increase of the transport-induced ozone perturbation (+0.4 DU) in the already most affected area of Northern Hemisphere.
Comparison of one- and two-filter detectors for atmospheric 222Rn measurements under various meteorological conditions
Authors: Xia Y. , Sartorius H. , Schlosser C. , Stöhlker U. , Conen F. , Zahorowski W.
Published: June 2010

Abstract. Parallel monitoring of 222Rn and its short-lived progeny (218Po and 214Pb) were carried out from November 2007 to April 2008 close to the top of the Schauinsland mountain, partly covered with forest, in South-West Germany. Samples were aspired from the same location at 2.5 m above ground level. We measured 222Rn with a dual flow loop, two-filter detector and its short-lived progeny with a one-filter detector. A reference sector for events, facing a steep valley and dominated by pasture, was used to minimize differences between 222Rn and progeny-derived 222Rn activity concentrations. In the two major wind sectors covered by forest to a distance between 60 m and 80 m towards the station progeny-derived 222Rn activity concentration was on average equal to 87% (without precipitation) and 74% (with precipitation) of 222Rn activity concentration. The observations show that most of the time both detector types follow the same pattern. Still, there is no single disequilibrium factor that could be used to exactly transform short-lived progeny to 222Rn activity concentration under all meteorological conditions.
Quantifying nitrous oxide emissions from Chinese grasslands with a process-based model
Authors: Zhang F. , Qi J. , Li F. M. , Li C. S. , Li C. B.
Published: June 2010

Abstract. As one of the largest land cover types, grassland can potentially play an important role in the ecosystem services of natural resources in China. Nitrous oxide (N2O) is a major greenhouse gas emitted from grasslands. Current N2O inventory at a regional or national level in China relies on the emission factor method, which is based on limited measurements. To improve the accuracy of the inventory by capturing the spatial variability of N2O emissions under the diverse climate, soil and management conditions across China, we adopted an approach by utilizing a process-based biogeochemical model, DeNitrification-DeComposition (DNDC), to quantify N2O emissions from Chinese grasslands. In the present study, DNDC was tested against datasets of N2O fluxes measured at eight grassland sites in China with encouraging results. The validated DNDC was then linked to a GIS database holding spatially differentiated information of climate, soil, vegetation and management at county-level for all the grasslands in the country. Daily weather data for 2000–2007 from 670 meteorological stations across the entire domain were employed to serve the simulations. The modelled results on a national scale showed a clear geographic pattern of N2O emissions. A high-emission strip showed up stretching from northeast to central China, which is consistent with the eastern boundary between the temperate grassland region and the major agricultural regions of China. The grasslands in the western mountain regions, however, emitted much less N2O. The regionally averaged rates of N2O emissions were 0.26, 0.14 and 0.38 kg nitrogen (N) ha−1 y−1 for the temperate, montane and tropical/subtropical grasslands, respectively. The annual mean N2O emission from the total 337 million ha of grasslands in China was 76.5 ± 12.8 Gg N for the simulated years.
Coral Cd/Ca and Mn/Ca records of ENSO variability in the Gulf of California
Authors: Carriquiry J. D. , Villaescusa J. A.
Published: June 2010

Abstract. We analyzed the trace element ratios Cd/Ca and Mn/Ca in three coral colonies (Porites panamensis (1967–1989), Pavona clivosa (1967–1989) and Pavona gigantea (1979–1989)) from Cabo Pulmo reef, Southern Gulf of California, Mexico, to assess the oceanographic changes caused by El Niño – Southern Oscillation (ENSO) events in the Eastern Tropical North Pacific (ETNP). Interannual variations in the coral Cd/Ca and Mn/Ca ratios showed clear evidence that incorporation of Cd and Mn in the coral skeleton was influenced by ENSO conditions, but the response for each metal was controlled by different processes. The Mn/Ca ratios were significantly higher during ENSO years (p<0.05) relative to non-ENSO years for the three species of coral. In contrast, the Cd/Ca was systematically lower during ENSO years, but the difference was significant (p<0.05) only in Pavona gigantea. A decrease in the incorporation of Cd and a marked increase in Mn indicated strongly reduced vertical mixing in the Gulf of California during the mature phase of El Niño. The oceanic warming during El Niño events produces a relaxation of upwelling and a stabilization of the thermocline, which may act as a physical barrier limiting the transport of Cd from deeper waters into the surface layer. In turn, this oceanic condition can increase the residence time of particulate-Mn in surface waters, allowing an increase in the photo-reduction of particulate-Mn and the release of available Mn into the dissolved phase. These results support the use of Mn/Ca and Cd/Ca ratios in biogenic carbonates as tracers of increases in ocean stratification and trade wind weakening and/or collapse in the ETNP during ENSO episodes.
A triple-moment blowing snow-atmospheric model and its application in computing the seasonal wintertime snow mass budget
Authors: Yang J. , Yau M. K. , Fang X. , Pomeroy J. W.
Published: June 2010

Abstract. Many field studies have shown that surface sublimation and blowing snow transport and sublimation have significant influences on the snow mass budget in many high latitude regions. We developed a coupled triple-moment blowing snow-atmospheric modeling system to study the influence of these processes on a seasonal time scale over the Northern Hemisphere. Two simulations were performed. The first is a 5 month simulation for comparison with snow survey measurements over a Saskatchewan site to validate the modeling system. The second simulation covers the 2006/2007 winter period to study the snow mass budget over the Northern Hemisphere. The results show that surface sublimation is significant in Eurasian Continent and the eastern region of North America, reaching a maximum value of 200 mm SWE (Snow Water Equivalent). Over the Arctic Ocean and Northern Canada, surface deposition with an average value of 30 mm SWE was simulated. Blowing snow sublimation was found to return up to 50 mm SWE back to the atmosphere over the Arctic Ocean, while the divergence of blowing snow transport contributes only a few mm SWE to the change in snow mass budget. The results were further stratified in 10 degree latitudinal bands. The results show that surface sublimation decreases with an increase in latitude while blowing snow sublimation increases with latitude. Taken together, the surface sublimation and blowing snow processes was found to distribute 23% to 52% of winter precipitation over the three month winter season.
Prospecting for safe (low fluoride) groundwater in the Eastern African Rift: the Arumeru District (Northern Tanzania)
Authors: Ghiglieri G. , Balia R. , Oggiano G. , Pittalis D.
Published: June 2010

Abstract. A multidisciplinary research effort, including geological, hydrogeological, hydro-chemical, geophysical and hydrological investigations, was aimed at locating a source of safe groundwater for a district of northern Tanzania, within the western branch of the East Africa Rift Valley, where water shortage is common and much of the surface water carries unacceptable levels of dissolved fluoride. The 440 km2 study area lies in the northern part of Arumeru district and is dominated by Mt. Meru (4565 m a.s.l.). The local climate is semi-arid, with distinct wet and dry seasons. Four hydrogeological complexes were identified, occurring within different volcanic formations, either alone or superimposed upon one another. The groundwater flow system was interpreted from the spatial distribution of the springs, combined with a lithology- and geometry-based reconstruction of the aquifers. The dominant pattern consists of a multi-directional flow from the higher elevations in the south towards the lower areas in the north, but this is complicated by structures such as grabens, faults, lava domes and tholoids. After the identification of the major fluoride source, an interference pattern between groundwater and high fluoride surface water was drawn. Finally, vertical electrical soundings were performed to define the location of aquifers in regions where release of fluoride was prevented. The methodological approach for the prospecting of safe water in a semi-arid, fluoride polluted region was validated by the drilling of a 60 m deep well capable of supplying at least 3.8 l/s of low fluoride, drinkable water.
Comment on "A praxis-oriented perspective of streamflow inference from stage observations – the method of Dottori et al. (2009) and the alternative of the Jones Formula, with the kinematic wave celerity computed on the looped rating curve" by Koussis (2009)
Authors: Koussis A. D.
Published: June 2010

Abstract. The estimation of transient streamflow from stage measurements is indeed important and the study of Dottori, Martina and Todini (2009) (henceforth DMT) is useful, however, DMT seem to miss certain of its practical aspects. The goal is to infer the discharge from measurements of the stage conveniently and with accuracy adequate for practical work. This comment addresses issues of the applicability of the DMT method in the field. DMT also advocate their method as a replacement of the widely used Jones Formula. The Jones Formula was modified by Thomas (Henderson, 1966) to include the temporal derivative of the depth, instead of the spatial one, to specifically allow discharge estimation from at-a-section stage observations. The outcome of the comparison is not surprising in view of this approximation. However, this discussion intends to show that, properly evaluated, the praxis-oriented Jones Formula, which did well in the tests, can perform better than DMT imply. It will be also documented that the DMT methodology relates to a known method for computing flood depth profiles.
Simple estimation of fastest preferential contaminant travel times in the unsaturated zone: application to Rainier Mesa and Shoshone Mountain, Nevada
Authors: Ebel B. A. , Nimmo J. R.
Published: June 2010

Abstract. Simulating contaminant transport in unsaturated zones with sparse hydraulic property information is a difficult, yet common, problem. When contaminant transport may occur via preferential flow, simple modeling approaches can provide predictions of interest, such as the first arrival of contaminant, with minimal site characterization. The conceptual model for unsaturated zone flow at two areas within the Nevada Test Site, Rainier Mesa and Shoshone Mountain, establishes the possibility of preferential flow through lithologies between potential radionuclide sources and the saturated zone. Lithology, saturated or near-saturated conditions in portions of the rock matrix, and relatively high recharge rates may act in concert at Rainier Mesa to promote preferential flow, despite the semi-arid climate. After identifying preferential flow as a possible contaminant transport process at Rainier Mesa and Shoshone Mountain, we apply a simple model to estimate fastest unsaturated travel times for conservatively-transported radionuclides to initially reach the saturated zone. Preferential flow travel times at Rainier Mesa are tens to hundreds of years for non-ponded water sources and one to two months for continuously-ponded water sources. If preferential flow occurs at Shoshone Mountain, the fastest travel times are approximately twice the Rainier Mesa estimates. A siliceous rock unit is present at Shoshone Mountain that may provide a barrier to preferential flow; if so, estimated transport times increase to more than a thousand years. Our analysis of unsaturated transport of radionuclides via preferential flow, using a relatively simple model, suggests that contaminated locations associated with continuously-supplied water sources, such as effluent ponds and water-filled tunnels, may have significantly shorter radionuclide travel times than locations not associated with such sources. The simple approach demonstrated here for estimating travel times can be useful in situations where predictions are needed by managers for the fastest arrival of contaminants, yet budgetary or time constraints preclude more rigorous analysis, and when additional model estimates are needed for comparison (i.e. model abstraction).
Groundwater use for irrigation – a global inventory
Authors: Siebert S. , Burke J. , Faures J. M. , Frenken K. , Hoogeveen J. , Döll P. , Portmann F. T.
Published: June 2010

Abstract. Irrigation is the most important water use sector accounting for about 70% of the global freshwater withdrawals and 90% of consumptive water uses. While the extent of irrigation and related water uses are reported in statistical databases or estimated by model simulations, information on the source of irrigation water is scarce and very scattered. Here we present a new global inventory on the extent of areas irrigated with groundwater, surface water or non-conventional sources, and we determine the related consumptive water uses. The inventory provides data for 15 038 national and sub-national administrative units. Irrigated area was provided by census-based statistics from international and national organizations. A global model was then applied to simulate consumptive water uses for irrigation by water source. Globally, area equipped for irrigation is currently about 301 million ha of which 38% are equipped for irrigation with groundwater. Total consumptive groundwater use for irrigation is estimated as 545 km3 yr−1, or 43% of the total consumptive irrigation water use of 1 277 km3 yr−1. The countries with the largest extent of areas equipped for irrigation with groundwater, in absolute terms, are India (39 million ha), China (19 million ha) and the United States of America (17 million ha). Groundwater use in irrigation is increasing both in absolute terms and in percentage of total irrigation, leading in places to concentrations of users exploiting groundwater storage at rates above groundwater recharge. Despite the uncertainties associated with statistical data available to track patterns and growth of groundwater use for irrigation, the inventory presented here is a major step towards a more informed assessment of agricultural water use and its consequences for the global water cycle.
Heat Transfer in Combustion Systems
Authors: Xu Jinliang
Published: June 2010

Combustion is one of the most difficult processes to deal with in Nature and engineering. It involves simultaneous three‐dimensional multiphase fluid dynamics, heat transfer (conduction, convection, and radiation), chemical kinetics, and the turbulent mixing of different species, all of which processes are coupled to each other. Chemical kinetics is heavily dependent on the temperature level, while thermal analysis is also strongly related to the energy utilization efficiency of the whole system when coal, oil, or gas is combusted. Thus, heat transfer is a very important issue to be considered. This chapter provides a brief review on heat transfer in combustion systems, with the three heat transfer modes – conduction, convection, and radiation – being discussed separately. For each heat transfer mode, the basic concept is introduced, including the important dimensionless parameters, theory, and some analytical or empirical correlations; heat transfer mechanisms, as applied to combustion systems, are then reviewed. Within the chapter, analytical or empirical correlations are provided for the thermal analysis of combustion systems, together with details of recent research into heat transfer modes in industrial combustion systems. It is hoped that the chapter will be helpful in both the design and thermal analysis of combustion systems.
Combustion Kinetic Modeling
Authors: Javed Muhammed Tayyeb , Irfan Naseem , Ibrahim Muhammad Asim
Published: June 2010

Combustion is a complex phenomenon characterized by the interaction and competition of various physical and chemical processes. The correct description of chemical changes requires the application of reaction mechanisms that consist of several hundreds or thousands of elementary reactions. This creates an opportunity for kinetic modeling to play important role in understanding the combustion phenomenon. This chapter provides an overview of combustion modeling, the main aim being to present a comprehensive knowledge base for combustion kinetic modeling. The coupling of fluid dynamics and chemical kinetics using commercial software such as CHEMKIN and FLUENT is also discussed. Moreover, an exemplary approach for reducing complex chemical reaction mechanisms is illustrated with reference to an H2+ O2mixture in an adiabatic system. This approach involves the identification of redundant species via rate sensitivity analysis, and of redundant reactions, by principal component analysis of the rate sensitivity matrix. An eigenvalue–eigenvector analysis is used to extract meaningful kinetic information from linear sensitivity coefficients computed for all species of chemical mechanism at several time points. The main advantage of this method lies in its ability to reveal those parts of the mechanism, which consist of strongly interacting reactions, and to indicate their importance within the mechanism. By using the above procedures, reduced reaction mechanisms could be developed at different chosen conditions and employed in CFD codes in place of detailed mechanisms, giving due consideration to flow fields.
Fuel Cells
Authors: Yuan Xiao‐Zi , Wang Haijiang
Published: June 2010

This chapter presents an overview of contemporary fuel cell technology. After an introduction to the fuel cell and its history, fuel cell theories are described, including the principles, thermodynamics, and reaction kinetics, laying the foundations of a basic understanding of fuel cell technologies. The different types of fuel cell, such as PEMFC, SOFC, AFC, PAFC, and MCFC, are then described, and the state‐of‐the‐art components, systems, and performances of each fuel cell type are discussed. Cell applications are then outlined, including stationary power generation, transportation, backup power, and small portable power applications. Finally, the major challenges and barriers to fuel cell commercialization are summarized.
Explosion Safety
Authors: Andrews Gordon E. , Phylaktou Herodotos N.
Published: June 2010

In this chapter, explosion stoichiometry is reviewed as air/fuel by mass for gases vapors, mists, and dusts. The measurement of lean flammability limits is reviewed, and legislated methods of measurement are outlined and compared with the previously accepted methods. The legislated methods provide about 15% leaner flammability limits than have previously been accepted. Applications of stoichiometry are discussed for explosion hazards, fuel tank explosions, and boiling liquid expanding vapor explosions (BLEVEs). The influence of temperature and pressure on flammability is reviewed. The problem of explosions in the vapor space of flammable liquid storage tanks is discussed, with aircraft fuel tank vapor space explosions as the main application. The generation of a wind ahead of an explosion is discussed, and linked to flame speed and burning velocity. The reactivity parameterKG, which is used in explosion vent design, is shown to be directly related to the laminar burning velocity. Explosion protection using venting is reviewed, and the physics underlying the legislated vent design equations described, together with some shortcomings in the design procedures.
Eulerian (Field) Monte Carlo Methods for Solving
PDF
Transport Equations in Turbulent Reacting Flows
Authors: Sabel'nikov Vladimir , Soulard Olivier
Published: June 2010

This chapter reviews some recent progress made in the field of Eulerian (field) Monte Carlo (EMC) methods, used for solving probability density function (PDF) transport equations in turbulent reacting flows. The framework of this review includes both Reynolds‐averaged Navier–Stokes (RANS) and large eddy simulation (LES) approaches, and both composition and velocity–composition PDFs. Instead of stochastic particles, as in Lagrangian Monte Carlo (LMC) methods, stochastic Eulerian fields are used to represent the PDF in EMC methods. These fields evolve according to stochastic partial differential equations (SPDEs), stochastically equivalent to the PDF equation. These SPDEs are derived from Lagrangian stochastic ordinary differential equations (SODEs), in the same way as in classical hydrodynamics one transforms the Navier–Stokes equations written in Lagrangian variables into Eulerian coordinates. Boundary conditions for the stochastic fields are discussed. From a numerical point of view, recent publications give evidence that EMC methods converge more rapidly than LMC methods. Further, EMC methods offer an additional advantage over LMC methods: they allow typical Eulerian transport solvers to be employed, thus facilitating the coupling in hybrid EMC–RANS or EMC–LES algorithms. The novel hybrid EMC–RANS is developed and then applied to a premixed methane–air flame stabilized by a backward‐facing step. Other examples of recent applications are reviewed, including the simulation of the auto‐ignition of a hydrogen jet issuing into a co‐flow of vitiated hot air with a scalar EMC–LES method and the simulation of an NO plume in the atmosphere with a scalar EMC–RANS method. Finally, potential future developments and areas of EMC methods are highlighted.
Overview of Liquid Fuels
Authors: van Rheinberg Oliver
Published: June 2010

The sections in this article are

Introduction

Crude Oil and Refinery – Production of Petroleum‐Based Liquid Fuels

Atmospheric Distillation

Vacuum Distillation

Thermal Cracking and Visbreaking

Catalytic Cracking

Hydrotreating

Hydrodesulfurization

Hydrocracking

Hydrogenation

Isomerization and Catalytic Reforming

Alkylation

Polymerization

Classification of Liquid Fuels

Petroleum‐Based Fuels

Renewable Fuels

Political Regulation and Directives

Chemical and Physical Properties of Liquid Fuels

Main Components of Petroleum‐Based Fuels

Aliphatic Hydrocarbons

Aromatic Hydrocarbons

Phenols

Physical and Chemical Properties of Aliphatic and Aromatic Hydrocarbons

Sulfur Species

Gasoline and Common Renewable Fuels

Diesel and Common Renewable Fuels

Kerosene

Marine and Residual Fuels

Stability of Fuels

Auto‐Oxidation – Aging Mechanism of Petroleum‐Based Fuels

Aging Mechanism of Fatty Acid Methyl Esters
Oil Outlook
Authors: Clemens Torsten
Published: June 2010

The sections in this article are

Introduction

Formation and Migration of Oil

Oil Reserves Classification

Oil Resources

Oil Production History and Reserves Development

Oil Production Forecast

Oil Production Based on Currently Producing Fields

Oil Production from Discovered Fields that Will be Developed

Oil Production from Yet to be Found Fields

Oil Production Due to Additional Enhanced Oil Recovery (EOR) and UnconventionalOil Production

Oil Production from Natural Gas Liquids

Implications of Increased Oil Demand/Production

Impact ofCO2Emissions

Oil Price Outlook

Discussion and Conclusion
Small‐Scale Biomass Combustion
Authors: Gaderer Matthias , Volz Florian , Kunde Robert
Published: June 2010

The sections in this article are

Introduction and Summary

Biomass Fuels

Biomass Combustion Techniques

Combustion Process

Manually Operated Systems

Log Wood Combustor Systems

Log Wood Fired Heating Systems

Automatically Fed Combustors

Combustion Concepts for Automatically Fed Firing Systems

Automatically Operated Wood Chip and Pellet Heating Systems

Emissions

Electricity Production and Combined Heat and Power
Pulverized Coal‐Fired Boilers
Authors: Zhang Hai , Lu Junfu
Published: June 2010

The sections in this article are

Introduction

PC
Combustion and
PC
Fired Boiler

Physical Properties of
PC
Particles

Conventional Layout of a
PC
Boiler

Heating Surfaces and Water‐Vapor Path in a
PC
Boiler

Heat Transfer Calculation Procedure of a
PC
Boiler

Some Theories

Theoretical Air and Coefficient of Excess Air

Heat Balance and Efficiency of a
PC
Boiler

Ignition of
PC
Particles

Char Combustion

NO

x

Formation Mechanisms

Thermal NO

Fuel
NO

PC
Fired Furnace

Furnace Layout and Firing Type

Cross‐Section Heat Release Rates Selection

Volumetric Heat Release Rates Selection

Empirical Heat Transfer Calculation in the Furnace

General Introduction

Heat Input to the Furnace

Emissivity of the Flame and the Furnace

Empirical Heat Transfer Calculation in the Furnace

PC
Fired Burners

General Introduction

Arrangement of Burners

Low

NO
x

burners (
LNB
)

Examples of
LNBs

Boat‐Shaped Bluff‐Body Burner

Double
PA
Channel Burner

DRB
Burner

WR
Burner

PM
Burner and Vertical Rich/Lean

Louver Damper Burner and Bias Combustion

In‐Furnace
HTAC
Burner

Outlook
Gasification of Biomass and Waste
Authors: Gómez‐Barea Alberto , Leckner Bo
Published: June 2010

Gasification increases the opportunities of using biomass and waste as an energy source because the fuel is converted into a fuel gas suitable for various applications. The variety of methods for gasification of solid biofuels is described, illustrating the main types of gasifier and technology used to generate fuel gas for various applications. The difference between gasification of biofuels and coal is emphasized, underlining the impact of the fuels on the design and operation of the gasifier. Gas cleaning options are treated on the basis of gasification technology and end‐gas application. The commercial status of biomass and waste gasification is discussed, outlining the areas where R&D efforts are currently focused.
Agglomeration in Fluidized Bed Combustion: Mechanisms, Detection, and Counteraction
Authors: van Ommen J. Ruud , Lin Weigang
Published: June 2010

Agglomeration of bed material is a major operational problem in fluidized bed combustion, especially when using biofuels. The main mechanism of agglomeration involves the formation of low melting point compounds, which results in increased particle stickiness and formation of agglomerates. The presence of alkali components from the biofuels leads to reactions with silica from the bed material, forming alkali silicates that have a melting point below the typical operating temperatures of about 850 °C. In addition, hydrodynamics and particle interaction mechanisms will play a role. If no counteraction is taken, severe agglomeration can eventually result in defluidization of the bed and subsequent shut‐down of the installation. Therefore, an early warning system to reliably detect agglomeration is of high importance. Such a system typically consists of the measurement of operating variables such as pressure coupled with analysis of these data. Different methods proposed in the literature are reviewed in this chapter. As soon as agglomeration has been detected, appropriate counteractions should be taken, such as changing the operating conditions or using additives. Alternatively, different bed materials can be used or the fluidized bed design may be adapted to become less susceptible to agglomeration.
Ash Fouling of Boiler Tubes and Thermophysical Properties of Deposits
Authors: Ots Arvo
Published: June 2010

A brief overview is presented of ash fouling of heat transfer surfaces of boiler and the thermophysical properties of deposits. Loose and bound ash deposit formation on transverse‐flow boiler tubes is treated. Composition of the bound deposits differs from the composition of fly ash passing through the heat transfer surface. Ash deposited on boiler tubes is examined as a porous material with the effective thermal conductivity. At higher temperatures, heat exchange in a porous body also becomes affected by radiant heat transfer inside the material. The radiation properties of ash deposits are also discussed. The radiation flux originating from the ash particle layer and deposit layer is spectral in the region of short wavelengths but for a smooth slag layer the selectivity is negligible.
HCCICombustion Chemistry, Reduced Kinetic Mechanisms and Controlling Strategies
Authors: Machrafi Hatim
Published: June 2010

The sections in this article are

Introduction

Present Situation

HCCIEngines, A New Alternative

HCCICombustion

Definition

Problem of Implementing theHCCIMethod

Chemical Kinetics inHCCICombustion

Chemical Combustion Mechanism of Iso‐Octane

Low‐Temperature Interval

Intermediate‐Temperature Interval

High‐Temperature Interval

Chemical Combustion Mechanism of Iso‐octane

Chemical Combustion Mechanism of Toluene

Initiation Reactions

Benzene Sub‐Mechanism

Resume of the Auto‐Ignition Process

Kinetic Mechanisms for the Study ofHCCICombustion

General Discussion about the Cool Flame Phenomenon

Reduced Kinetic Mechanisms

Experimental Validation of a Reduced Kinetic Mechanism

Controlling Strategies

Control Methods

Kinetic Mechanisms to Control the Auto‐Ignition

Existing Applications of theHCCIEngine and its Future

Conclusions
Laser Ignition
Authors: Phuoc Tran X.
Published: June 2010

The sections in this article are

Introduction

Laser Ignition Energy

Breakdown Threshold Laser Energy

Multiphoton Ionization

Cascade Breakdown Ionization

Spark Evolution

Ignition Mechanism

Homogeneous Hot‐Gas Model

Blast Wave Ignition Model

A Hot Gas Model

Potential Applications and Research Needs

Laser‐Induced Gas Breakdown and Evolution in High‐Speed and Highly Turbulent Streams

Laser Ignition for Stabilization of Ultra‐Lean and High Speed Combustion Applications

Laser Ignition under Engine and/or Engine‐Like Conditions

Development of a Diode‐Pumped Solid State Laser for Laser Ignition Applications

Conclusions
Combustion Synthesis
Authors: Specchia Stefania , Finocchio Elisabetta , Busca Guido , Specchia Vito
Published: June 2010

Combustion synthesis (CS) is becoming one of the most important ways to produce a wide range of advanced porous ceramic or metallic materials. These include ceramic oxide like nanostructured catalysts. In CS, the heat released from the redox chemical reaction is used to produce useful materials. Depending upon the nature of the reactants, and the amount of heat made available during reaction, CS is in general mainly described as self‐propagating high temperature synthesis (SHS), solution combustion synthesis (SCS), and flame synthesis (FS). Among these, SCS is an attractive alternative for the production of particular materials of high value compared to the more conventional and expensive preparation routes.

SCS processes are characterized by relatively medium heating oven temperatures (350–600 °C), fast heating rates, and short reaction times. SCS, in fact, offers a unique synthesis route via a highly exothermic redox reaction between metal nitrates and an organic fuel to produce multi‐component oxides. The reaction is self‐propagating and able to sustain high temperatures for a time long enough to complete the synthesis reaction and form the desired product. Therefore, the reaction is over in a few minutes without the use of high temperature furnaces. The final product is usually of high purity and well crystallized with nanometric size clusters, owing to the very small residence time at high temperature, a condition allowing the formation of a very large number of particles without huge growing effects. As a consequence, it is characterized by high values of both surface area and specific volume. Moreover, the significant gas rate produced during the synthesis process breaks up the large agglomerates and yields a porous mass that is easily crumbled into a fine powder. Furthermore, SCS, suitably adapted, is easily tunable to complex systems to produce directlyin situstructured catalysts. In recent years this technique has been used to produce very fine, crystalline powders, without the intermediate steps that other conventional synthesis routes would require. These features make CS an attractive alternative for the production of ceramic materials compared to the conventional more expensive and time consuming processes. Examples of SCS andin situSCS for the production of structured catalysts for combustion of natural gas and preferential oxidation of carbon monoxide are described.
Nanosized Photocatalysts in Environmental Remediation
Authors: Wilcoxon Jess P. , Abrams Billie L.
Published: June 2010

We review the science and technology underlying the synthesis of nanosized photocatalysts and their application in environmental remediation. Certain types of semiconductor nanoparticles in both dispersed and supported form can oxidize toxic organic chemicals in liquid, gas and solid phases. This mineralization process can be driven by light and an optimized process can function under ambient conditions of temperature and pressure, producing CO2and dilute mineral acids. Such photocatalysis is a potentially inexpensive alternative to other methods for destroying both chemical and biological toxins in the environment. Our review includes discussion of several nanosized photocatalysts with an emphasis on the metal oxide TiO2and metal sulfides, especially MoS2. We discuss their characterization and the factors which influence their photocatalytic activity and selectivity. Issues such as control of size, quantum confinement, surface chemistry and carrier recombination rate play an important role in the functioning of these photocatalysts. Finally, we summarize some recent applications of TiO2films in environmental remediation technology which are just being commercialized. We also discuss future research needs in this area required for an economically viable technology.
Physics of Computational Elements
Authors: Zhirnov Victor V. , Cavin Ralph K.
Published: June 2010

This chapter considers the physical principles and trends in nanoscale information‐processing devices. It provides a coherent description and the performance analysis of diverse nanoelectronic devices that operate in different physical domains. A generic device abstraction for computational elements is developed for a uniform treatment of several classes of nanodevice that use different information carriers, such as electrons, spins, or photons. Estimates of theoretically attainable performance and of geometric scaling limits for these diverse devices are also provided.
Indium Arsenide (InAs) Nanowire Wrapped‐Insulator‐Gate Field‐Effect Transistor
Authors: Wernersson Lars‐Erik , Bryllert Tomas , Fröberg Linus , Lind Erik , Thelander Claes , Samuelson Lars
Published: June 2010

In the highly competitive R&D‐field aimed at extensions or replacements of standard transistors and integrated circuits, two primary approaches are envisioned: either as modifications to today's technology (e.g. via development of high‐kdielectrics), or as the development of more radically approaches on the device and integration level. One of these non‐disruptive technologies involves the use of vertical transistors in the form of monolithically grown, one‐dimensional III–V transistor channels, with a coaxial configuration of a metal‐insulator‐semiconductor field‐effect transistor (MISFET) implementation. This geometry and material choice promises a competitive new technology that may extend the scaling roadmap. The main benefits are the ideal terms of electrostatics, as well as down‐scaling offered in the coaxial configuration and the possibility of increasing the drive current and enhancing device performance with the addition of designed heterostructures as part of the transistor technology. In this chapter, the state‐of‐the‐art vertical wrap‐gate nanowire‐based transistor is described, and this family of transistors as wrapped‐insulator‐gate field‐effect transistors (abbreviated as WIGFET) is outlined.