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1.
Article in English | MEDLINE | ID: mdl-31080299

ABSTRACT

This paper presents a new wide-ranging correlation for the thermal conductivity of n-hexadecane based on critically evaluated experimental data. The correlation is designed to be used with a recently published equation of state, and it is valid from the triple point up to 700 K and pressures up to 50 MPa. We estimate the uncertainty at a 95% confidence level to be 4% over the aforementioned range, with the exception of the dilute-gas range where the uncertainty is 2.7% over the temperature range 583 to 654 K. The correlation behaves in a physically reasonable manner when extrapolated to the full range of the equation of state, but the uncertainties are larger outside of the validated range, and also in the critical region.

2.
Article in English | MEDLINE | ID: mdl-31092958

ABSTRACT

This paper presents a new wide-ranging correlation for the viscosity of ammonia based on critically evaluated experimental data. The correlation is designed to be used with a recently developed equation of state, and it is valid from the triple point to 725 K, at pressures up to 50 MPa. The estimated uncertainty varies depending on the temperature and pressure, from 0.6% to 5%. The correlation behaves in a physically reasonable manner when extrapolated to 100 MPa, however care should be taken when using the correlations outside of the validated range.

3.
Article in English | MEDLINE | ID: mdl-30983644

ABSTRACT

The available experimental data for the thermal conductivity of 13 inorganic molten salts have been critically examined with the intention of establishing thermal conductivity reference correlations. All experimental data have been categorized into primary and secondary data according to the quality of measurement specified by a series of criteria. Standard reference correlations are proposed for the following molten salts (with estimated uncertainties at the 95 % confidence level given in parentheses): LiNO3 (7 %), NaNO3 (7 %), KNO3 (15 %), NaBr (15 %), KBr (15 %), RbBr (15 %), LiCl (17 %), NaCl (20 %), KCl (17 %), RbCl (17%), CsCl (10 %), NaI (17 %), and RbI (20 %).

4.
Article in English | MEDLINE | ID: mdl-30996494

ABSTRACT

In this paper, reference values and reference correlations for the thermal conductivity and viscosity of pure fluids are reviewed. Reference values and correlations for the thermal conductivity and the viscosity of pure fluids provide thoroughly evaluated data or functional forms and serve to help calibrate instruments, validate or extend models, and underpin some commercial transactions or designs, among other purposes. The criteria employed for the selection of thermal conductivity and viscosity reference values are also discussed; such values, which have the lowest uncertainties currently achievable, are typically adopted and promulgated by international bodies. Similar criteria are employed in the selection of reference correlations, which cover a wide range of conditions, and are often characterized by low uncertainties in their ranges of definition.

5.
J Phys Chem Ref Data ; 46(3)2017 Sep.
Article in English | MEDLINE | ID: mdl-29230074

ABSTRACT

This paper presents new wide-ranging correlations for the viscosity and thermal conductivity of n-undecane based on critically evaluated experimental data. The correlations are designed to be used with a recently published equation of state that is valid from the triple point to 700 K, at pressures up to 500 MPa, with densities below 776.86 kg m-3. The estimated uncertainty for the dilute-gas viscosity is 2.4%, and the estimated uncertainty for viscosity in the liquid phase for pressures up to 60 MPa over the temperature range 260 K to 520 K is 5%. The estimated uncertainty is 3% for the thermal conductivity of the low-density gas, and 3% for the liquid over the temperature range from 284 K to 677 K at pressures up to 400 MPa. Both correlations behave in a physically reasonable manner when extrapolated to the full range of the equation of state, however care should be taken when using the correlations outside of the validated range. The uncertainties will be larger outside of the validated range, and also in the critical region.

6.
J Phys Chem Ref Data ; 46(3)2017 Sep.
Article in English | MEDLINE | ID: mdl-28970643

ABSTRACT

The available experimental data for the thermal conductivity of liquid bismuth, cobalt, germanium and silicon have been critically examined with the intention of establishing thermal conductivity reference correlations. All experimental data have been categorized into primary and secondary data according to the quality of measurement specified by a series of criteria. The proposed standard reference correlations for the thermal conductivity of liquid bismuth, cobalt, germanium, and silicon are respectively characterized by uncertainties of 10, 15, 16 and 9.5% at the 95% confidence level.

7.
J Phys Chem Ref Data ; 46(2)2017 Jun.
Article in English | MEDLINE | ID: mdl-28785120

ABSTRACT

This paper presents new wide-ranging correlations for the viscosity and thermal conductivity of ethyl fluoride (R161) based on critically evaluated experimental data. The correlations are designed to be used with a recently published equation of state that is valid from 130 K to 450 K, at pressures up to 100 MPa. The estimated uncertainty at a 95% confidence level is 2% for the viscosity of low-density gas (pressures below 0.5 MPa), and 3% for the viscosity of the liquid over the temperature range from 243 K to 363 K at pressures up to 30 MPa. The estimated uncertainty is 3% for the thermal conductivity of the low-density gas, and 3% for the liquid over the temperature range from 234 K to 374 K at pressures up to 20 MPa. Both correlations may be used over the full range of the equation of state, but the uncertainties will be larger, especially in the critical region.

8.
J Phys Chem Ref Data ; 46(1)2017 Feb.
Article in English | MEDLINE | ID: mdl-28584386

ABSTRACT

New, wide-range reference equations for the thermal conductivity of cyclohexane as a function of temperature and density are presented. The equations are based in part upon a body of experimental data that has been critically assessed for internal consistency and for agreement with theory whenever possible. We estimate the uncertainty (at the 95% confidence level) for the thermal conductivity of cyclohexane from the triple point (279.86 K) to 650 K at pressures up to 175 MPa to be 4% for the compressed liquid and supercritical phases. For the low-pressure gas phase (up to 0.1 MPa) over the temperature range 280 K to 680 K, the estimated uncertainty is 2.5%. Uncertainties in the critical region are much larger, since the thermal conductivity approaches infinity at the critical point and is very sensitive to small changes in density.

9.
J Phys Chem Ref Data ; 45(3)2016 Sep.
Article in English | MEDLINE | ID: mdl-27818536

ABSTRACT

New, wide-range reference equations for the thermal conductivity of ethene and propene as a function of temperature and density are presented. The equations are based in part upon a body of experimental data that has been critically assessed for internal consistency and for agreement with theory whenever possible. For ethene, we estimate the uncertainty (at the 95% confidence level) for the thermal conductivity from 110 K to 520 K at pressures up to 200 MPa to be 5% for the compressed liquid and supercritical phases. For the low-pressure gas phase (to 0.1 MPa) over the temperature range 270 K to 680 K, the estimated uncertainty is 4%. The correlation is valid from 110 K to 680 K and up to 200 MPa, but it behaves in a physically reasonable manner down to the triple point and may be used at pressures up to 300 MPa, although the uncertainty will be larger in regions where experimental data were unavailable. In the case of propene, data are much more limited. We estimate the uncertainty for the thermal conductivity of propene from 180 K to 625 K at pressures up to 50 MPa to be 5% for the gas, liquid, and supercritical phases. The correlation is valid from 180 K to 625 K and up to 50 MPa, but it behaves in a physically reasonable manner down to the triple point and may be used at pressures up to 100 MPa, although the uncertainty will be larger in regions where experimental data were unavailable. For both fluids, uncertainties in the critical region are much larger, since the thermal conductivity approaches infinity at the critical point and is very sensitive to small changes in density.

10.
J Phys Chem Ref Data ; 45(1)2016 Mar.
Article in English | MEDLINE | ID: mdl-27064300

ABSTRACT

This paper contains new, representative reference equations for the thermal conductivity of carbon dioxide. The equations are based in part upon a body of experimental data that has been critically assessed for internal consistency and for agreement with theory whenever possible. In the case of the dilute-gas thermal conductivity, we incorporated recent theoretical calculations to extend the temperature range of the experimental data. Moreover, in the critical region, the experimentally observed enhancement of the thermal conductivity is well represented by theoretically based equations containing just one adjustable parameter. The correlations are applicable for the temperature range from the triple point to 1100 K and pressures up to 200 MPa. The overall uncertainty (at the 95% confidence level) of the proposed correlation varies depending on the state point from a low of 1% at very low pressures below 0.1 MPa between 300 K and 700 K, to 5% at the higher pressures of the range of validity.

11.
Eur Radiol ; 26(3): 780-7, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26024847

ABSTRACT

OBJECTIVES: To date, PROPELLER MRI, a breathing-motion-insensitive technique, has not been assessed for cystic fibrosis (CF) lung disease. We compared this technique to CT for assessing CF lung disease in children and adults. METHODS: Thirty-eight stable CF patients (median 21 years, range 6-51 years, 22 female) underwent MRI and CT on the same day. Study protocol included respiratory-triggered PROPELLER MRI and volumetric CT end-inspiratory and -expiratory acquisitions. Two observers scored the images using the CF-MRI and CF-CT systems. Scores were compared with intra-class correlation coefficient (ICC) and Bland-Altman plots. The sensitivity and specificity of MRI versus CT were calculated. RESULTS: MRI sensitivity for detecting severe CF bronchiectasis was 0.33 (CI 0.09-0.57), while specificity was 100% (CI 0.88-1). ICCs for bronchiectasis and trapped air were as follows: MRI-bronchiectasis (0.79); CT-bronchiectasis (0.85); MRI-trapped air (0.51); CT-trapped air (0.87). Bland-Altman plots showed an MRI tendency to overestimate the severity of bronchiectasis in mild CF disease and underestimate bronchiectasis in severe disease. CONCLUSIONS: Motion correction in PROPELLER MRI does not improve assessment of CF lung disease compared to CT. However, the good inter- and intra-observer agreement and the high specificity suggest that MRI might play a role in the short-term follow-up of CF lung disease (i.e. pulmonary exacerbations). KEY POINTS: PROPELLER MRI does not match CT sensitivity to assess CF lung disease. PROPELLER MRI has lower sensitivity than CT to detect severe bronchiectasis. PROPELLER MRI has good to very good intra- and inter-observer variability. PROPELLER MRI can be used for short-term follow-up studies in CF.


Subject(s)
Cone-Beam Computed Tomography/methods , Cystic Fibrosis/diagnostic imaging , Cystic Fibrosis/pathology , Magnetic Resonance Imaging/methods , Adolescent , Adult , Child , Female , Follow-Up Studies , Humans , Lung/diagnostic imaging , Lung/pathology , Male , Middle Aged , Motion , Observer Variation , Reproducibility of Results , Sensitivity and Specificity , Young Adult
12.
J Hazard Mater ; 261: 653-68, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-23995562

ABSTRACT

This paper addresses the current important problem of modelling the dispersion of toxic gases released in the urban terrains (i.e. neighbourhood scale) by the Detached Eddy Simulation (DES). This approach is a resolution that lays between the Reynolds Averaged Navier-Stokes and Large Eddy Simulation models and focuses especially on establishing a better balance between efficiency and accuracy. Herein are presented the theoretical approach of a new model, which is based on the DES and the Spalart-Almaras turbulent closure and a number of validation tests like the flow and the dispersion over and around a single building and an array of buildings. Overall, employed validation metrics were within the acceptable limits and the model demonstrated an acceptable agreement with the experimental datasets which confirms the use of this approach for the modelling and dispersion of gases in complex terrains like a city.


Subject(s)
Air Pollutants , Models, Theoretical , Air Movements , Cities , Gases
13.
Environ Technol ; 32(5-6): 593-608, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21877540

ABSTRACT

Industrial activities are sources of high emission rates of particulate matter. The existence of many such industrial plants close to a densely populated area can have a severe effect on human health. The effects can be even worse when these emissions are added to existing background concentration levels. This study deals with the assessment of the primary particulate matter pollution caused by industrial activities close to the city of Thessaloniki in Greece. An atmospheric dispersion and regulatory model was employed, i.e. AERMOD from the US Environmental Pollution Agency. A new PM10 emission sources inventory was prepared for the main industrial plants of the area and the annual and monthly average concentrations from 2003 to 2007 were calculated. The results from AERMOD were validated against data from available monitoring stations and showed reasonably good agreement. It was estimated that industry contributes approximately 30% of primary PM10 on the western suburbs of the city and about 7% in the city centre. The effect of the wind direction was also studied and it was illustrated that the frequent southwest winds present higher concentration levels than the strong north ones.


Subject(s)
Industry , Models, Statistical , Particulate Matter/analysis , Cities , Geography , Greece , Seasons , Weather
15.
Isr J Psychiatry Relat Sci ; 27(2): 92-8, 1990.
Article in English | MEDLINE | ID: mdl-2211072

ABSTRACT

Six female postmenopausal psychiatric inpatients with rheumatoid arthritis (RA), domineering personality, hypochondriasis, alexithymia and perfectionism are presented. None of the patients fully responded to antidepressant drug treatment. Five of the six women were professionally engaged in sewing, which might be considered a mechanical risk factor for rheumatoid arthritis. Several psychiatric aspects of RA are discussed, particularly the existence of the "arthritic personality" and the influence of psychological stress in RA patients.


Subject(s)
Arthritis, Rheumatoid/psychology , Depressive Disorder/psychology , Hypochondriasis/psychology , Occupational Diseases/psychology , Textile Industry , Aged , Female , Humans , Middle Aged , Personality Tests , Sick Role
16.
Isr J Psychiatry Relat Sci ; 26(4): 223-43, 1989.
Article in English | MEDLINE | ID: mdl-2698868

ABSTRACT

A false belief exists that depressed patients are not creative. On the contrary, they have an urge to create--the creative spells are equivalent to the depression. They express themselves more easily through painting than through speech. They express their repressed feelings and ideas of sin and affect, suicidal tendency, etc., and in some cases, the spontaneous paintings have prophetic meaning. It is much easier for them to express their feelings through universal signs and symbols such as: face, posture; church, tower, bell, cross; coffin, tomb, cemetery, grave; skeleton, skull, bones; tree, mountain, boat, chair.


Subject(s)
Art , Creativity , Depressive Disorder/psychology , Paintings , Humans
17.
Harefuah ; 113(7-8): 186-9, 1987 Oct.
Article in Hebrew | MEDLINE | ID: mdl-3428743
20.
Harefuah ; 111(3-4): 102-4, 1986 Aug.
Article in Hebrew | MEDLINE | ID: mdl-3792946
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