RAPID DETERMINATION OF MOISTURE IN GRAIN: II. CALIBRATION AND COMPARISON OF ELECTRICAL MOISTURE METERS WITH VACUUM OVEN FOR HARD RED SPRING WHEAT

1934 ◽  
Vol 11 (4) ◽  
pp. 409-447 ◽  
Author(s):  
W. H. Cook ◽  
J. W. Hopkins ◽  
W. F. Geddes
Keyword(s):  
Moisture Content ◽  
Temperature Coefficient ◽  
Calibration Curve ◽  
Rapid Determination ◽  
Low Grade ◽  
Vacuum Oven ◽  
Hard Red Spring Wheat ◽  
Moisture Contents ◽  
Experimental Errors ◽  
General Reliability

The electrical moisture meters studied were: the Burton-Pitt, Davies, Limbrick, hand-operated and motor-operated Tag-Heppenstall. The Burton-Pitt is a "dielectric" type; all the others depend on the resistance principle.The calibration curve for the Burton-Pitt instrument is parabolic within the range 11.0 to 17.0% moisture. The resistance type instruments all show a linear relation between moisture content and the logarithm of the resistance at moisture contents below 17.0%, and a parabolic relation at higher moisture contents. The accuracy of the meters, as determined by the experimental errors and the standard error of prediction of the vacuum oven moisture, decreases in the following order within the moisture range, 11.0 to 17.0%: motor-operated Tag-Heppenstall, Limbrick, hand-operated Tag-Heppenstall, Burton-Pitt and Davies. At higher moisture contents than 17.0% the Burton-Pitt and Davies instruments are definitely unreliable, and the remaining meters are also less precise.The temperature coefficient of the wheat-instrument system was found to be appreciably different from that of the wheat alone in the Limbrick and Burton-Pitt. The temperature coefficient was also found to differ somewhat in different moisture ranges. The effect of humidity is most pronounced in the Limbrick, but is in all instruments small in comparison with that of temperature. The limited number of low grade samples studied appeared to follow the same calibration curve as high grade samples in all meters and 28 samples of the hard-kernelled variety Garnet were also found to follow the calibration curve deduced from the general reliability experiments in all meters, with the exception of the hand-operated Tag-Heppenstall. The discrepancy with this meter is not great and can be attributed to the roll space being unsuitable for this hard-kernelled variety.The moisture range satisfactorily covered by the instruments decreases in the order: motor-operated Tag-Heppenstall, hand-operated Tag-Heppenstall, Limbrick, Burton-Pitt and Davies. In all cases the upper limit is finally determined by the increasing inaccuracy of the meter, rather than by its physical range, which is limited at 21.5% moisture with the Limbrick only when used at the highest sensitivity. With wheat below 11.0% moisture, only the Burton-Pitt and Tag-Heppenstall instruments can be used, and the calibration curve for the Burton-Pitt obtained with wheat of higher moisture content cannot be extrapolated over this lower range.

RAPID DETERMINATION OF MOISTURE IN GRAIN: III. CALIBRATION AND COMPARISON OF ELECTRICAL MOISTURE METERS WITH VACUUM OVEN FOR AMBER DURUM WHEAT, BARLEY AND OATS

1934 ◽  
Vol 11 (5) ◽  
pp. 547-563 ◽  
Author(s):  
W. H. Cook ◽  
J. W. Hopkins ◽  
W. F. Geddes
Keyword(s):  
Durum Wheat ◽  
Spring Wheat ◽  
Rapid Determination ◽  
Limited Range ◽  
Oven Method ◽  
Vacuum Oven ◽  
Hard Red Spring Wheat ◽  
Significant Difference ◽  
Moisture Basis ◽  
Limited Moisture

The previous study has been extended to include durum wheat, barley and oats. The hand-operated Tag-Heppenstall meter was found to be unsatisfactory with these grains, as they would not feed into the roller electrodes in a suitable manner. The Burton-Pitt gave erratic results with these grains and it was only possible to calibrate this meter over a limited moisture range, and even over this range it was more inaccurate than the other meters. Qualitatively the calibration curves for these three grains, in the Limbrick and motor Tag-Heppenstall, were similar to those previously obtained with hard red spring wheat. The actual resistance and the slope of the curves were, however, somewhat different for the different grains. The standard error of prediction shows that the motor-operated Tag-Heppenstall was the most accurate meter for use with durum wheat and barley, while the Limbrick was superior with oats. With the limited number of samples available it was impossible to detect any significant difference between the temperature coefficients, in any particular meter, of the different grains. When converted to a moisture basis the correction factors were practically the same as for hard red spring wheat.The results from the entire investigation show that the Brown-Duvel method is more accurate than the 130 °C. air oven method with all grains studied. The motor-operated Tag-Heppenstall meter is as accurate as the Brown-Duvel with hard red spring wheat, over the moisture range 11.0 to 17.0%, and is superior to the air oven method over this limited range. Otherwise the rapid analytical methods are more accurate than any of the moisture meters tested with any of the grains. The meters fall in the following order of decreasing accuracy over the moisture range 11.0 to 17.0%:–with hard red spring wheat; motor Tag-Heppenstall, Limbrick, hand Tag-Heppenstall, Burton-Pitt and Davies: with durum wheat and barley; motor Tag-Heppenstall, Limbrick and Burton-Pitt: and with oats; Limbrick, Burton-Pitt and motor Tag-Heppenstall. Where a meter is not mentioned no tests were made, the instrument having been omitted because it gave no promise of practical utility.

scholarly journals The Influence of Moisture Content on the Time-Dependent Characteristics of Rock Material and Its Application to the Construction of a Tunnel Portal

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Xiaojun Liu ◽  
Chao Yang ◽  
Jing Yu
Keyword(s):  
Moisture Content ◽  
Deformation Behaviour ◽  
Creep Behaviour ◽  
Three Dimensional ◽  
Viscosity Coefficient ◽  
Guizhou Province ◽  
Creep Model ◽  
Low Grade ◽  
Saturation Degree ◽  
Moisture Contents

Uniaxial compression creep experiments were carried out for low-grade metamorphic slate samples (located in the southeastern area of Guizhou province, China) with different moisture contents, using an Instron electric-fluid servo-compression machine. Based on the experimental results, a detailed analysis was made of the effect of moisture content on the strength and deformation behaviour of the slate specimens. The three-parameter generalised Kelvin model was identified to describe the creep behaviour of the low-grade metamorphic slate with different moisture contents. There is an approximately linear negative correlation between the elastic modulus and the saturation degree, and the viscoelastic modulus and viscosity coefficient show a negative exponent correlation with the saturation degree. The Kelvin creep model considering the moisture degradation effect was established and a three-dimensional finite difference model was developed with the softwareFLAC3Dto validate the creep model. A three-dimensional numerical analysis was then performed to simulate the tunnel excavation process. The results show that the influence of moisture and creep of the surrounding rocks is needed for estimating the deformation of complex tunnel portals.

RAPID DETERMINATION OF MOISTURE IN GRAIN: I. COMPARISON OF 130 °C. AIR OVEN AND BROWN-DUVEL METHODS WITH VACUUM OVEN METHOD

1934 ◽  
Vol 11 (3) ◽  
pp. 264-289 ◽  
Author(s):  
W. H. Cook ◽  
J. W. Hopkins ◽  
W. F. Geddes
Keyword(s):  
Moisture Content ◽  
Durum Wheat ◽  
Spring Wheat ◽  
Standard Error ◽  
Systematic Bias ◽  
Consistent Estimate ◽  
Sampling Errors ◽  
Oven Method ◽  
Vacuum Oven ◽  
Hard Red Spring Wheat

Some 300 samples of hard red spring wheat, 50 of amber durum wheat and 75 each of oats and barley, covering the entire moisture range of commercial importance, were employed in the comparisons. Provision was made for statistical estimation of sampling errors, errors of method and errors of observation. A two-stage drying procedure was employed for the vacuum oven determinations which were taken as the reference standard. Sampling errors, average difference between identical ovens and errors due to daily fluctuations were all larger than the standard deviation of duplicates ("experimental error"), the sampling error being the largest.A comparison of the Hobart and Wiley grinders shows the latter to be superior for preparing wheat for the 130 °C. air oven determination. The air oven consistently underestimates the moisture content of all the grains tested, as compared with the vacuum oven, the deficit increasing with the actual moisture content. This systematic bias may be eliminated by means of a linear correction equation. After allowing for the observed sampling errors and errors of the vacuum oven determination, the net standard error of prediction with the air oven using a Wiley mill is, with hard red spring wheat 0.24%, with amber durum wheat 0.12%, with barley 0.20% and with oats 0.20% moisture.The Brown-Duvel method also underestimates the moisture content, this deficit also increasing with the actual moisture content in the case of spring and amber durum wheat. After applying a correction equation to eliminate the systematic bias, the net standard error of prediction of moisture by this method was found to be: with hard red spring wheat 0.16%, with durum wheat 0.09%, with barley 0.12% and with oats 0.13%. The Brown-Duvel method, therefore, when carefully operated makes possible a more consistent estimate of the actual moisture content, as determined by the vacuum oven, than does the 130 °C. air oven method. As with the vacuum oven, both the 130 °C. air oven and the Brown-Duvel appear to be subject to slight variations affecting all the determinations made on any particular day.

A COMPARATIVE STUDY OF TEN ELECTRICAL METERS FOR DETERMINING MOISTURE CONTENT OF WHEAT

1949 ◽  
Vol 27f (10) ◽  
pp. 382-397 ◽  
Author(s):  
I. Hlynka ◽  
V. Martens ◽  
J. A. Anderson
Keyword(s):  
Moisture Content ◽  
Comparative Study ◽  
Spring Wheat ◽  
Standard Error ◽  
Temperature Effects ◽  
Standard Errors ◽  
Regression Equations ◽  
Two Stage ◽  
Vacuum Oven ◽  
Hard Red Spring Wheat

Ten electrical moisture meters were tested with 159 samples of Canadian hard red spring wheat, of Grades 1, 2, 3, and 4 Northern, representing a moisture range of 11 to 17%. The two-stage vacuum oven and Brown–Duvel methods were used as bases of comparison. Regression equations, standard errors of estimate, and data on temperature effects are reported. The standard error of estimate of vacuum oven results was 0.15% for the Brown–Duvel method, 0.23% for the Tag–Heppenstall meter, and 0.28% for the Universal meter. Other meters had higher errors of estimate.

scholarly journals Field and laboratory ad hoc calibrations of Virrib and ThetaProbe dielectric sensors for soil moisture measurements

2008 ◽  
Vol 3 (No. 4) ◽  
pp. 199-214 ◽  
Author(s):  
F. Doležal ◽  
T. Litschmann ◽  
J. Kučera ◽  
J. Peterková ◽  
J. Zavadil ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Calibration Curve ◽  
Ad Hoc ◽  
Soil Moisture Content ◽  
Seasonal Pattern ◽  
Repeated Measurements ◽  
Field Calibration ◽  
Moisture Contents ◽  
Moisture Variation

For the research of irrigation optimization and nitrate leaching it is important to know the short-term soil moisture variation during percolation episodes as well as its seasonal pattern. Dielectric soil moisture sensors Virrib (AMET – Consortium) and ThetaProbe ML2x (Delta-T) were used for this purpose over several years for measuring soil moisture content at hourly intervals in Valečov (49°38’40” N, 14°30’25” E, 461 m a.s.l.), Czech Republic, in a deep loamy Stagnosol soil underlain by weathered paragneiss. One-point field calibration was made each spring at the time of sensor installation over three (for Virribs) or two (for ThetaProbes) consecutive years by taking sensor readings and soil samples (at least one 100 cm3 core sample near to each sensor) in parallel. A supplementary check was then made in the laboratory by taking readings of individual sensors, inserted into pre-made loamy-sand mixtures with various moisture contents. During both the field calibration and the laboratory check, the readings were taken manually, using either the AMET hand-held meter or the EMS ModuLog datalogger. The results suggest that the average slope of the secondary Virrib calibration curve (defined as the plot of y = sensor readings in terms of moisture content vs. x = soil moisture content determined gravimetrically) is near to unity, but the offsets are quite large and vary from probe to probe. The axial zone of influence of the Virrib sensors is up to about 30 cm, as it follows from both laboratory and field observations. The results of the laboratory check of Virribs were biased, because the volume of the soil was not large enough and the soil had different dry bulk densities at different moisture contents. The field secondary calibration curve of ThetaProbes appears to be roughly linear, in contrast to the laboratory calibration curve, because of absence of very low moisture contents in the field. If the same calibration line is applied to several different depths, then its slope is statistically significantly lower then unity, due to the dependence of ThetaProbe readings on the soil bulk density. The overall accuracy of the sensors and its components due to different factors is estimated from the statistics of repeated measurements.

The Smoulder Stream of Cigarettes / Zur Kenntnis des Glimmstromes von Cigaretten

1965 ◽  
Vol 3 (2) ◽  
Author(s):  
F. Seehofer ◽  
W. Schulz
Keyword(s):  
Moisture Content ◽  
Spatial Position ◽  
High Yield ◽  
Physical Conditions ◽  
Moisture Contents ◽  
Cigarette Paper ◽  
First Time

AbstractThe phenomenon of the smoulder stream flowing through the cigarette during smouldering and during the puff intervals is demonstrated for the first time and its dependence upon physical conditions is examined. The volume of the smoulder stream can amount up to 180 ml per cigarette. Increasing draw resistance of the cigarette and augmenting moisture content of the tobacco as well as perforation of the cigarette paper have a decreasing effect on volume and velocity of the smoulder stream. The porosity of the cigarette paper has no perceptible influence. The spatial position of the cigarette affects volume and velocity of the smoulder stream. The influence exercised by the smoulder stream on the yields of total condensate, nicotine, phenols, aldehydes, and acroleine when the cigarette tip is open during the puff intervals is determined. When the moisture contents of the tobacco were extremely high, yield decreases reaching 50 % could be observed.

Developing a Linearization Method to Determine Optimum Blending for Surimi with Varied Moisture Contents Using Linear Programming

2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Hyeon W. Park ◽  
Jae W. Park ◽  
Won B. Yoon
Keyword(s):  
Linear Programming ◽  
Moisture Content ◽  
Standard Procedure ◽  
Unit Cost ◽  
Linearization Method ◽  
Model Parameters ◽  
Additional Information ◽  
Moisture Contents ◽  
Design Variables ◽  
Critical Moisture

AbstractNovel algorithm to determine the least cost formulation of a surimi blend was developed using linear programming (LP). Texture properties and the unit cost of surimi blend at the target moisture content were used as constraint functions and the objective function, respectively. The mathematical models to describe the moisture content dependence of the ring tensile properties were developed using critical moisture content, and the model parameters were used for the least cost LP (LCLP) model. The LCLP model successfully predicted the quality of surimi blend. Sensitivity analysis was used to obtain an additional information when the perturbations of design variables are provided. A standard procedure to determine the least cost formulation for blending surimi with varied moisture contents was systematically developed.

scholarly journals Experimental Study on the Softening Characteristics of Sandstone and Mudstone in Relation to Moisture Content

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Gui-chen Li ◽  
Chong-chong Qi ◽  
Yuan-tian Sun ◽  
Xiao-lin Tang ◽  
Bao-quan Hou
Keyword(s):  
Moisture Content ◽  
Vertical Displacement ◽  
Surface Porosity ◽  
Shear Tests ◽  
Moisture Contents ◽  
Dynamic Finite Element ◽  
Rock Types ◽  
Underground Roadway ◽  
The Stability ◽  
Kinetics Of

The kinetics of fluid-solid coupling during immersion is an important topic of investigation in rock engineering. Two rock types, sandstone and mudstone, are selected in this work to study the correlation between the softening characteristics of the rocks and moisture content. This is achieved through detailed studies using scanning electron microscopy, shear tests, and evaluation of rock index properties during exposure to different moisture contents. An underground roadway excavation is simulated by dynamic finite element modeling to analyze the effect of moisture content on the stability of the roadway. The results show that moisture content has a significant effect on shear properties reduction of both sandstone and mudstone, which must thus be considered in mining or excavation processes. Specifically, it is found that the number, area, and diameter of micropores, as well as surface porosity, increase with increasing moisture content. Additionally, stress concentration is negatively correlated with moisture content, while the influenced area and vertical displacement are positively correlated with moisture content. These findings may provide useful input for the design of underground roadways.

scholarly journals Steel-shot method for measuring the density of soils

2010 ◽  
Vol 47 (11) ◽  
pp. 1299-1304 ◽  
Author(s):  
Reed B. Freeman ◽  
Chad A. Gartrell ◽  
Lillian D. Wakeley ◽  
Ernest S. Berney ◽  
Julie R. Kelley
Keyword(s):  
Moisture Content ◽  
Rapid Determination ◽  
Content Volume ◽  
Test Method ◽  
Unit Weight ◽  
Soil Density ◽  
Engineering Construction ◽  
Steel Shot ◽  
Time Requirements

The density of soil is crucial in engineering, construction, and research. Standard methods to determine density use procedures, equipment or expendable materials that limit their effectiveness in challenging field conditions. Some methods require burdensome logistics or have time requirements that limit their use or the number of tests that can be executed. A test method, similar to the sand-cone method, was developed that uses steel shot as the material to which a volume of soil is compared to calculate soil density. Steel shot is easily recovered and reused, eliminating the need for specialty sand and calibrated cones or containers, and allows rapid determination of the volume of displaced soil. Excavated soil also provides measurements of total mass and moisture content. Volume, mass, and moisture content are applied in simple calculations to determine wet and dry densities and unit weight of the soil. Proficiency in performing the test can be achieved with minimal training, and the required kit can be assembled for a reasonable cost. Field uses of the method in dry environments in a variety of soil types demonstrated that the method can produce repeatable results within 2% of the values of soil density determined by traditional methods, with advantages in logistics.

Optimization of drying of low-grade coal with high moisture content using a disc dryer

2014 ◽  
Vol 124 ◽  
pp. 267-274 ◽  
Author(s):  
Seung-Hyun Moon ◽  
In-Soo Ryu ◽  
Seung-Jae Lee ◽  
Tae-In Ohm
Keyword(s):  
Moisture Content ◽  
Low Grade ◽  
High Moisture Content ◽  
High Moisture
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