Determination of Moisture Content in Synthetic Moulding Sand on the Grounds of Relative Permittivity Measurement

AbstractThe presented research was aimed at searching for an exact and effective method of determining moisture content in traditional moulding sands. By measuring resonance frequency and quality factor of a waveguide resonance cavity, relative permittivity was determined for different synthetic moulding sands. Analysis of the presented results confirms a linear relation between relative permittivity values and moisture content values in the selected traditional moulding sands. The obtained linear relationship can be used as a reference characteristic for evaluation of humidity of moulding sand.

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Performance Research of a Solid Desiccant Material Regenerating Directly with Solar Energy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.291-294.145 ◽

2013 ◽

Vol 291-294 ◽

pp. 145-151 ◽

Cited By ~ 1

Author(s):

Wan Sheng Yang ◽

Huang Huan Guo ◽

Zhang Yuan Wang ◽

Xu Dong Zhao

Keyword(s):

Thermal Conductivity ◽

Solar Radiation ◽

Moisture Content ◽

Linear Relation ◽

Water Saturation ◽

Equivalent Thermal Conductivity ◽

Simulated Solar Radiation ◽

Performance Research ◽

Desiccant Material

This paper studied the thermal and physical properties of a new solar solid desiccant material, including the equivalent thermal conductivity under different moisture content conditions and penetrability under different simulated solar radiation. The results showed that the equivalent thermal conductivity of the material was related to the moisture content and water saturation. In unsaturated state, the equivalent thermal conductivity increased with the increase of the moisture content and presented a linear relation in certain range. When reached saturation, the equivalent thermal conductivity decreased with the increase of the moisture content. These figures could provide the basis for the determination of the thickness of the dehumidification bed and optimization of the design of the dehumidification system.

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Measurement of Electrical Properties as Effectiveness Appraisal of Microwave Absorption by Moulding and Core Sands Subject to Microwave Utilization

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0117 ◽

2014 ◽

Vol 59 (2) ◽

pp. 713-716 ◽

Cited By ~ 1

Author(s):

D. Nowak ◽

K. Granat ◽

B. Opyd

Keyword(s):

Electromagnetic Field ◽

Electrical Properties ◽

Perturbation Method ◽

Microwave Absorption ◽

Loss Tangent ◽

Field Measurements ◽

Precise Determination ◽

Resonance Cavity ◽

Waveguide Resonance

Abstract Within the research, carried-out were examinations of foundry rejects in form of waste moulding and core sands in order to determine effectiveness of the microwave utilization process. Presented are measurements of permittivity and loss tangent that determine behaviour of materials in electromagnetic field. Measurements were performed on a stand of waveguide resonance cavity that permits precise determination of the above-mentioned parameters with the perturbation method. Examination results of five waste moulding sands confirm that effectiveness of microwave utilization depends on electrical properties of the sandmixes (permittivity and loss tangent).

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Determination of the International Sensitivity Index of a New Near-Patient Testing Device to Monitor Oral Anticoagulant Therapy

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657641 ◽

1997 ◽

Vol 78 (02) ◽

pp. 855-858 ◽

Cited By ~ 25

Author(s):

Armando Tripodi ◽

Veena Chantarangkul ◽

Marigrazia Clerici ◽

Barbara Negri ◽

Pier Mannuccio Mannucci

Keyword(s):

Linear Relationship ◽

Whole Blood ◽

Oral Anticoagulant ◽

Oral Anticoagulant Therapy ◽

Oral Anticoagulants ◽

Calibration Model ◽

Testing Device ◽

Data Points ◽

Near Patient Testing

SummaryA key issue for the reliable use of new devices for the laboratory control of oral anticoagulant therapy with the INR is their conformity to the calibration model. In the past, their adequacy has mostly been assessed empirically without reference to the calibration model and the use of International Reference Preparations (IRP) for thromboplastin. In this study we reviewed the requirements to be fulfilled and applied them to the calibration of a new near-patient testing device (TAS, Cardiovascular Diagnostics) which uses thromboplastin-containing test cards for determination of the INR. On each of 10 working days citrat- ed whole blood and plasma samples were obtained from 2 healthy subjects and 6 patients on oral anticoagulants. PT testing on whole blood and plasma was done with the TAS and parallel testing for plasma by the manual technique with the IRP CRM 149S. Conformity to the calibration model was judged satisfactory if the following requirements were met: (i) there was a linear relationship between paired log-PTs (TAS vs CRM 149S); (ii) the regression line drawn through patients data points, passed through those of normals; (iii) the precision of the calibration expressed as the CV of the slope was <3%. A good linear relationship was observed for calibration plots for plasma and whole blood (r = 0.98). Regression lines drawn through patients data points, passed through those of normals. The CVs of the slope were in both cases 2.2% and the ISIs were 0.965 and 1.000 for whole blood and plasma. In conclusion, our study shows that near-patient testing devices can be considered reliable tools to measure INR in patients on oral anticoagulants and provides guidelines for their evaluation.

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