1,922 research outputs found

    On-line measurement of heat of combustion

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    An experimental method for an on-line measurement of heat of combustion of a gaseous hydrocarbon fuel mixture of unknown composition is developed. It involves combustion of a test gas with a known quantity of air to achieve a predetermined oxygen concentration level in the combustion products. This is accomplished by a feedback controller which maintains the gas volumetric flow rate at a level consistent with the desired oxygen concentration in the products. The heat of combustion is determined from a known correlation with the gas volumetric flow rate. An on-line microcomputer accesses the gas volumetric flow data, and displays the heat of combustion values at desired time intervals

    Lack of direct evidence for a functional role of voltage-operated calcium channels in juxtaglomerular cells

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    In this study we have examined the role of voltage-gated calcium channels in the regulation of calcium in juxtaglomerular cells. Using a combination of patch-clamp and single-cell calcium measurement we obtained evidence neither for voltage-operated calcium currents nor for changes of the intracellular calcium concentration upon acute depolarizations of the cell membrane. Increases of the extracellular concentration of potassium to 80 mmol/l depolarized the juxtaglomerular cells close to the potassium equilibrium potential, but did not alter the intracellular calcium concentration neither in patch-clamped nor in intact Furaester-loaded cells. Moreover, basal renin secretion from a preparation enriched in mouse juxtaglomerular cells and from rat glomeruli with attached juxtaglomerular cells was not inhibited when extracellular potassium was isoosmotically increased to 56 mmol/l. In mouse kidney slices, however, depolarizing potassium concentrations caused a delayed inhibition at 56 mmol/l and a delayed stimulation of renin secretion at 110 mmol/l. Taken together, our study does not provide direct evidence for a role of voltage-activated calcium channels in the regulation of calcium and renin secretion in renal juxtaglomerular cells

    Investigation of paramagnetic response of metallic epoxies

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    The paramagnetic properties of epoxies which were impregnated with metal ions were examined as the primary task in this research. A major conclusion was that the quality control of the epoxies was insufficient to permit reliable evaluation. Subsequently, a new set of specimens is being prepared. As an additional task, a new method is investigated for estimating heats of combustion for saturated hydrocarbons. The results of that investigation have shown that the empirical approach is a promising method for on-line measurements

    Measurement of viscosity of gaseous mixtures at atmospheric pressure

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    Coefficients of viscosity of various types of gas mixtures, including simulated natural-gas samples, have been measured at atmospheric pressure and room temperature using a modified capillary tube method. Pressure drops across the straight capillary tube section of a thermal mass flowmeter were measured for small, well-defined, volume flow rates for the test gases and for standard air. In this configuration, the flowmeter provides the volumetric flow rates as well as a well-characterized capillary section for differential pressure measurements across it. The coefficients of viscosity of the test gases were calculated using the reported value of 185.6 micro P for the viscosity of air. The coefficients of viscosity for the test mixtures were also calculated using Wilke's approximation of the Chapman-Enskog (C-E) theory. The experimental and calculated values for binary mixtures are in agreement within the reported accuracy of Wilke's approximation of the C-E theory. However, the agreement for multicomponent mixtures is less satisfactory, possible because of the limitations of Wilkes's approximation of the classical dilute-gas state model

    A simplified method for determining heat of combustion of natural gas

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    A simplified technique for determination of the heat of combustion of natural gas has been developed. It is a variation of the previously developed technique wherein the carrier air, in which the test sample was burnt, was oxygen enriched to adjust the mole fraction of oxygen in the combustion product gases up to that in the carrier air. The new technique eliminates the need for oxygen enrichment of the experimental mixtures and natural gas samples and has been found to predict their heats of combustion to an uncertainty of the order of 1 percent

    Effect of crack propagation on crack tip fields

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    Crack closure influences fatigue crack growth rate and must be included in the design ofcomponents. Plasticity induced crack closure is intimately linked with the crack tip plastic deformation, whichbecomes residual as the crack propagates. The objective here is to study numerically the effect of crackpropagation on crack tip fields. The transient effect observed at the beginning of crack propagation is linked tothe hardening behavior of material. The effect of mesh refinement is studied, and a singular behavior is evident,which is explained by the sharp crack associated with mesh topology, composed of a regular pattern of squareelements. The plastic zone size measured perpendicularly to crack flank in the residual plastic wake is quantifiedand compared with literature models. Finally, the removal of material at the first node behind crack tip withload cycling was observed for plane strain state and some hardening models in plane stress state

    Feasibility of a nuclear gauge for fuel quantity measurement aboard aircraft

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    Capacitance fuel gauges have served as the basis for fuel quantity indicating systems in aircraft for several decades. However, there have been persistent reports by the airlines that these gauges often give faulty indications due to microbial growth and other contaminants in the fuel tanks. This report describes the results of a feasibility study of using gamma ray attenuation as the basis for measuring fuel quantity in the tanks. Studies with a weak Am-241 59.5-keV radiation source indicate that it is possible to continuously monitor the fuel quantity in the tanks to an accuracy of better than 1 percent. These measurements also indicate that there are easily measurable differences in the physical properties and resultant attenuation characteristics of JP-4, JP-5, and Jet A fuels. The experimental results, along with a suggested source-detector geometrical configuration are described

    The Relationship between Organizational Justice Perception and Self- efficacy in Staff of a Selected Educational Hospital: a case study

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    Background & Objectives: Hospitals are one of the important components in a health care system and have significant role in health of humans. Organizational justice shows the perception of fairness and equality in the workplace by staff and affects their behavior. This study examines the relationship between organizational justice perception and self-efficacy in employees of a selected hospital of Tabriz/ Iran. Methods: This was a cross-sectional descriptive- analytic study performed on 156 employees of one of the selected hospitals of Tabriz University of Medical Sciences. Chen, Gully & Eden Self-efficacy questionnaire and Rego and Cunha organizational justice questionnaire were used as data collection tools. Data analysis was done through SPSS23 and using analytic statistical tests such as Spearman correlation, Chi-Square and regression. Results: There was a significant positive relationship between dimensions of organizational justice and self- efficacy (P<0.01). Also, based on the results of regression analysis, information justice was a stronger predictor of self- efficacy. Eventually, the elements of procedural, interactions and information justice could predict 14% of variations of self- efficacy. Conclusion: Since dimensions of organizational justice affect employees' self- efficacy, hospital managers should find appropriate strategies for improving organizational justice in order to increase self- efficacy and ultimately the performance of their employees. Key¬words: Distributive justice, Procedural Justice, Interactional Justice, Informational Justice, Self efficacy, Staff, Educational Hospital Citation: Janati A, Chegini Z, Gholizadeh M, Naseri N, Ahmadi Z. The Relationship between Organizational Justice Perception and Self- efficacy in Staff of a Selected Educational Hospital: a case study. Journal of Health Based Research 2017; 3(2): 127-13
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