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Saturation Point (saturation + point)
Selected AbstractsAssessment of fire protection performance of water mist applied in exhaust ducts for semiconductor fabrication processFIRE AND MATERIALS, Issue 5 2005Yi-Liang Shu Abstract Fume exhaust pipes used in semiconductor facilities underwent a series of fire tests to evaluate the performance of a water mist system. The parameters considered were the amount of water that the mist nozzles used, the air flow velocity, the fire intensity and the water mist system operating pressure. In order to make a performance comparison, tests were also performed with a standard sprinkler system. The base case served as a reference and applied a single water mist nozzle (100 bar operating pressure, 7.3 l/min water volume flux and 200 µm mean droplet size) installed in the pipe (60 cm in diameter) subjected to a 350°C air flow with an average velocity of 2 m/s. In such a case, the temperature in the hot flow dropped sharply as the water mist nozzle was activated and reached a 60°C saturation point. Under the same operating conditions, four mist nozzles were applied, and made no further contribution to reducing the fire temperature compared with the case using only a single nozzle. Similar fire protection performances to that in the base case were still retained when the exhaust flow velocity increased to 3 m/s and the inlet air temperature was increased to 500°C due to a stronger input fire scenario, respectively. Changing to a water mist system produced a better performance than a standard sprinkler. With regard to the effect of operating pressure of water mist system, a higher operating pressure can have a better performance. The results above indicate that the droplet size in a water-related fire protection system plays a critical role. Copyright © 2005 John Wiley & Sons, Ltd. [source] Light acclimation of Chlamydomonas acidophila accumulating in the hypolimnion of an acidic lake (pH 2.6)FRESHWATER BIOLOGY, Issue 8 2005ANTJE GERLOFF-ELIAS Summary 1. The unicellular green alga Chlamydomonas acidophila accumulates in a thin phytoplankton layer in the hypolimnion (deep chlorophyll maximum, DCM) of an extremely acidic lake (Lake 111, pH 2.6, Lusatia, Germany), in which the underwater light spectrum is distorted and red-shifted. 2. Chlamydomonas acidophila exhibited a significantly higher absorption efficiency and a higher cellular chlorophyll b content when incubated in the red shifted underwater light of Lake 111 than in a typical, blue-green dominated, light spectrum. 3. Chlamydomonas acidophila has excellent low light acclimation properties (increased chlorophyll b content, increased oxygen yield and a low light saturation point for photosynthesis) that support survival of the species in the low light climate of the DCM. 4. In situ acclimation to the DCM under low light and temperature decreased maximum photosynthetic rate in autotrophic C. acidophila cultures, whereas the presence of glucose under these conditions enhanced photosynthetic efficiency and capacity. 5. The adaptive abilities of C. acidophila to light and temperature shown in this study, in combination with the absence of potent competitors because of low lake pH, most probably enable the unusual dominance of the green alga in the DCM of Lake 111. [source] Who Went to College?HIGHER EDUCATION QUARTERLY, Issue 4 2006Socio-Economic Inequality in Entry to Higher Education in the Republic of Ireland in 200 Ireland has experienced substantial increases in participation in higher education in recent years. This paper examines whether or not increased admission rates between the mid-1990s and 2000s led to a reduction in social class inequality in access to higher education. We draw on two data sets, one, a dedicated survey of new entrants to higher education in 2004, the other, a combination of the results of a series of school leavers' surveys conducted in the mid-1990s and early 2000s. We show that the period has been characterised by both continuity and change. Continuity is reflected in persistent social inequalities in access to higher education: the children of higher professionals and farmers, in particular, have maintained their privileged access to higher education. Change is reflected in some closing in relative social inequalities, partly arising as more advantaged groups reach a saturation point in progression to higher education, and partly due to the children of manual workers increasing their participation rates. [source] Physician supply, supplier-induced demand and competition: empirical evidence from a single-payer system,INTERNATIONAL JOURNAL OF HEALTH PLANNING AND MANAGEMENT, Issue 2 2006Sudha Xirasagar Abstract We examined the earnings of 8106 office-based (FTE) physicians in 2002 in Taiwan for evidence of supplier-induced demand (SID). We hypothesize that SID, operating in the form of mutual cross-specialty referral, will cause earnings to increase with total physician density (all specialties taken together), but simultaneously, decrease with increasing competition within specialties. We used multiple regression analyses controlling for high-user population, physician demographics and practice type. The evidence supports our hypotheses. Increasing total physician density (all specialties) is positively associated with earnings. Concurrently, within specialties, increased competition is associated with reduced earnings. The medical appropriateness of increasing health care utilization with increasing physician supply cannot be directly determined from the data. However, evidence of a steady earnings increase with increasing total physician density, which precludes a saturation point (of appropriate care levels) at some optimum physician density, substantiates SID in the office-based practice market. Empirically, our data suggest that the average market effect of physicians on one another is synergic when all specialties are considered together, but competitive within each specialty. Copyright © 2006 John Wiley & Sons, Ltd. [source] Beyond ,faith-based medicine' and EBMJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 4 2006John De Simone Abstract Rationale, aims and objectives, Longstanding debate on evidence-based medicine (EBM) may have reached a critical saturation point. I briefly report on systematic reviews on the recurring themes in the critical literature. In this context, some criticisms to EBM are substantial and enduring, although convincing arguments to contrast unresolved issues have yet to be produced. Nonetheless, few changes have been adopted and conservative attitudes persist in EBM. Despite its ,success', implementation in practice has been inexorably overshadowed leading to paradoxical shortcomings. This controversial scenario offers a formidable occasion to gain needed insight. The aim of this paper is to attempt a comprehensive analysis by reframing a number of key concerns, while furnishing pragmatic, interdisciplinary solutions for these deep-rooted dilemmas. In the interests of all stakeholders, I seek to promote a concerted effort to resolve conflict and build consensus. Methods, This paper explores a strategically unifying vision of primary care, based on current understanding of practice patterns, having a research-friendly ,common ground' where practitioners' information needs may be met. In addition, an analysis of existing problems identifies underlying ,root causes'. Moreover, I expediently reframe crucial matters by focusing on EBM, more than as a paradigm, as an organisation, hence amenable to a variety of cross-disciplinary analyses and solutions. Finally, recent state-of-the-art reviews on implementation and dissemination research are cited for the pertinent implications for study design and practice. Results, Present policies and influential testimonials on behalf of EBM encounter the pitfalls of hindering learning and progress through defensive attitudes and mechanisms. Current study designs and evaluation criteria must strive to adapt to real-world settings, rather than vice versa. Conclusions, The arguments exposed herein alter the terms of the debate on EBM and may outline a basis for initiatives with conflict-resolution and consensus-building scopes. [source] Seasonal Variation and Correlation with Environmental Factors of Photosynthesis and Water Use Efficiency of Juglans regia and Ziziphus jujubaJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 2 2008Hai-Bo Yang Abstract Both the photosynthetic light curves and CO2 curves of Juglans regia L. and Ziziphus jujuba Mill. var. spinosa in three seasons were measured using a LI-6400 portable photosynthesis system. The maximal net photosynthetic rate (Amax), apparent quantum efficiency(,), maximal carboxylation rate (Vcmax) and water use efficiency (WUE) of the two species were calculated based on the curves. The results showed that Amax of J. regia reached its maximum at the late-season, while the highest values of Amax of Z. jujuba occurred at the mid-season. The Amax of J. regia was more affected by relative humidity (RH) of the atmosphere, while that of Z. jujuba was more affected by the air temperature. Light saturation point (LSP) and Light compensation point (LCP) of J. regia had a higher correlation with RH of the atmosphere, those of Z. jujuba, however, had a higher correlation with air temperature. Vcmax of both J. regia and Z. jujuba had negative correlation with RH of the atmosphere. WUE of J. regia would decrease with the rise of the air temperature while that of Z. jujuba increased. Thus it could be seen that RH, temperature and soil moisture had main effect on photosynthesis and WUE of J. regia and Z. jujuba. Incorporating data on the physiological differences among tree species into forest carbon models will greatly improve our ability to predict alterations to the forest carbon budgets under various environmental scenarios such as global climate change, or with differing species composition. [source] Separation of fullerenes C60 and C70 using a crystallization-based processAICHE JOURNAL, Issue 7 2010Kui S. Kwok Abstract A crystallization-based process that separates pure fullerenes C60 and C70 from their mixture using o-xylene as the solvent has been developed. Isothermal solid,liquid equilibrium phase diagrams of the C60 -C70 -o-xylene ternary system for a number of temperatures were first determined at 1 atm. Taking advantage of the shift in solvent-free composition of the C60 -C70 double saturation point with temperature and based on the solid solution-forming phase behavior between C60 and C70, the flowsheet of a general crystallization process was then synthesized. It involved the fractionation of a C60 -C70 fullerene mixture into C60 -rich and C70 -rich solid solutions using temperature-swing crystallization, followed by purification of the solid solutions with multistage crystallization into pure C60 and C70 solids. To demonstrate process feasibility, bench-scale batch experiments were performed using a commercially available fullerene mixture that was pretreated by adsorption to remove higher fullerenes. C60 and C70 solids of purity higher than 99 wt % were obtained. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] A new heat balance for flow boilingAICHE JOURNAL, Issue 8 2007Francisco J. Collado Abstract Recently, one of the authors suggested calculating void fraction, an essential element in thermal-hydraulics, working with the "thermodynamic" quality instead of the usual "flow" quality. However, the standard heat balance is currently stated as a function of the "flow" quality. Therefore, we should search a new energy balance between the mixture enthalpy, based on "thermodynamic" quality, and the absorbed heat. This work presents the results of such analysis based on accurate measurements of the axial profile of the cross-sectional average void fraction in the region of boiling with subcooling for water at medium and high pressures taken by Moscow Power Institute (MPI) and Argonne National Laboratory (ANL). As main results, we find that, under uniform heat flux, the mixture enthalpy suffers an abrupt reduction of its slope upon passing saturation point, and a new slip ratio could balance heat with such mixture enthalpy. © 2007 American Institute of Chemical Engineers AIChE J, 2007 [source] Effects of advance organizers, mental models and abilities on task and recall performance using a mobile phone networkAPPLIED COGNITIVE PSYCHOLOGY, Issue 9 2006Janice Langan-Fox Mobile phone usage is now at saturation point in most Western countries. The current research investigated the usability of services provided by a mobile phone network, specifically whether two different forms (text, graphic) of an advance organizer (AO) assisted novice users in applying information supplied in a manual. It was hypothesized that a graphic AO would facilitate the development of coherent mental models of the network to enhance task performance, and that lower ability groups in particular would benefit from AOs. Contrary to prediction, the text AO group outperformed both the graphic AO and control groups. Lower ability groups also benefited more from a text AO than a graphic AO. Copyright © 2006 John Wiley & Sons, Ltd. [source] Interaction between aqueous solutions of polymer and surfactant and its effect on physicochemical propertiesASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2008Mohammad Yunus Khan Abstract Interaction between water-soluble polymers and anionic surfactants has been studied by surface tension and conductivity measurements. Sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (SDBS) were used as surfactant while polyacrylamide (PAA), commercial grade partially hydrolyzed polyacrylamide (PHPA), and xanthan gum were used as water-soluble polymers for the present study. The behavior of surfactant,polymer interaction was found to be dependent on both surfactant and polymer concentrations. After the critical aggregation concentration (CAC), interaction between the water-soluble polymer and surfactants was started and above the polymer saturation point (PSP) polymer was saturated by surfactant with no further change of surface tension and conductivity of the solution. It has also been found that alkali (NaOH) and salts (Na2CO3, NaCl) have significant influence on the polymer,surfactant interaction. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Wasserdampfsorptionsverhalten ausgewählter heimischer und überseeischer HolzartenBAUPHYSIK, Issue 2 2009Rudolf Popper Dipl.-Ing. Feuchte; Versuche Abstract An 21 heimischen und 11 überseeischen Holzarten wurde die Gleichgewichtsfeuchte bei 20 °C und 35, 50, 65, 80 und 95 % relativer Luftfeuchtigkeit experimentell in der Adsorptionsphase bestimmt. Aufbauend auf den experimentell bestimmten Mittelwerten wurden mit dem Hailwood-Horrobin-Modell (HH-Modell) ausgewählte Parameter wie Fasersättigungsfeuchte, mono- und polymolekulare Sorption, spezifische Oberfläche des Sorbenten, hypothetisches Molekulargewicht des Sorbenten sowie Unzugänglichkeit des Sorbenten zum Sorbat berechnet. Zusätzlich wurden Tabellen für die Gleichgewichtsfeuchte bei 20 °C und in 2-%-Schritten abgestufter relativer Luftfeuchtigkeit berechnet. Die mittels des HH-Modells berechnete Fasersättigungsfeuchte liegt für alle geprüften Holzarten im Bereich zwischen 22 bis 36 %, im Mittel bei ca. 30 %. Es treten erhebliche Abweichungen zwischen den einzelnen Holzarten in der Fasersättigungsfeuchte auf. Die Tendenzen für die Kenngrößen der Sorptionsanalyse wurden aufgezeigt. Water vapour sorption behaviour of selected domestic and overseas wood species. At 21 domestic and 11 overseas wood species the equilibrium moisture content at 20 °C and 35, 50, 65, 80 and 95% relative humidity was experimentally determined in the adsorption phase. The experimentally determined average values were computed with help of the Hailwood Horrobin model to get selected parameters such as fiber saturation point, mono- and polymolecular sorption, specific surface, hypothetical molecular weight as well as inaccessibility of the sorbent to the sorbate. Tables for the equilibrium moisture contents at 20 °C computed in 2% steps of relative humidity are presented. The fiber saturation point computed with the Hailwood-Horrobin model lies for all examined wood in the range from 22% to 36%, on the average with approx. 30%. There are substantial deviations in the fiber saturation point between the individual wood species. The tendencies for the characteristics of the sorption analysis were pointed out. [source] Representation of high-dimensional, molecular solid-liquid phase diagramsAICHE JOURNAL, Issue 12 2000Ketan D. Samant A generic framework for the representation of multicomponent molecular solid-liquid phase diagrams in the form of digraphs is presented. Pure components, eutectic points, and saturation points in the solid-liquid composition space are represented as vertices of the digraph. These vertices are connected to form edges on the basis of the adjacency matrix, which is constructed by following a set of generic rules derived from the Gibbs phase rule. These edges form the boundaries of high-dimensional saturation varieties. Included in the framework is a procedure for plotting high-dimensional isobaric and isothermal isobaric phase behavior in the form of projections and cuts. With this framework, solid-liquid phase behavior of multicomponent systems can be easily represented and studied. Applications include facilitation of experimental development of high-dimensional phase diagrams and synthesis of crystallization-based separation processes. The latter is illustrated with the separation of a quinary mixture. [source] Assessing the Impact of Agricultural Technology Adoption on Farmers' Well-being Using Propensity-Score Matching Analysis in Rural ChinaASIAN ECONOMIC JOURNAL, Issue 2 2010Haitao Wu O33; P36 The present paper assesses the impact of improved upland rice technology on farmers' well-being. The study uses propensity-score matching to address the problem of ,self-selection,' because technology adoption is not randomly assigned. It applies this procedure to household survey data collected in Yunnan, China in 2000, 2002 and 2004. The findings indicate that improved upland rice technology has a robust and positive effect on farmers' well-being, as measured by income levels and the incidence of poverty. The effect of technology on well-being shows a diminishing impact on producers' incomes. This implies that newer innovations are continuously needed to replace older technologies that have reached their saturation points. [source] | |||||||||||||||||||