Studies were conducted on the effects of grain angle on reproducibility and accurate measurement of moisture content of four wood samples using a pin-style moisture meter. The wood samples were partitioned into four q...Studies were conducted on the effects of grain angle on reproducibility and accurate measurement of moisture content of four wood samples using a pin-style moisture meter. The wood samples were partitioned into four quadrants and moisture contents were measured along the grain direction in the first and second quadrants from 0 degree to 150 degrees insteps of 30 degrees. Experimental results indicated that the average moisture content remained constant as the grain angle increased. Repeated measurements of moisture content at different grain angles or points on the wood surface showed similar patterns of variation. Within-point standard deviations of the moisture contents were greater than between-point standard deviations. A non-destructive method of measuring moisture content at the same location or point on the wood surfaces could not be proposed because of the high variation of moisture content when repeated measurements were taken at the same point. Instead, accurate measurements of moisture content could be obtained at random positions within a radius of 30 mm from the point of intersection of the moisture content axis and the grain angle.展开更多
Measuring the moisture content of cotton bales is an important step in controlling the quality of cotton produced and sold around the world. A non-contact microwave-based bale moisture meter, the Vomax 851-B （Vomax I...Measuring the moisture content of cotton bales is an important step in controlling the quality of cotton produced and sold around the world. A non-contact microwave-based bale moisture meter, the Vomax 851-B （Vomax Instrumentation through Samuel Jackson, Lubbock, TX） has been commercially available but independent verification of these measurements has not been available. This new commercial meter was examined at a commercial facility using both laboratory produced bales and actual commercially produced bales. In the laboratory phase, bales were prepared by the Cotton Ginning Research Unit for measurement on the commercial instrument as well as by the oven reference method; the potential effects of bale orientation and bale packaging were also studied with these samples. The commercial phase involved collecting lint samples from 50 bales, over 5 days, during the 2007 ginning season. The collected bale samples were tested by the oven reference method for moisture content and those readings were compared to the microwave-based meter readings for moisture content. Moisture content, as measured, covered a wide range from 4.2% to 7.2 %, wet basis. The Vomax measurements tracked variation in bale moisture content and correlated well with the reference method; however the measurements showed higher moisture content than determined by the oven method. The Vomax 851-B shows potential to provide a reliable cotton bale moisture content for use in controlling the moisture content for commercial ginning of cotton.展开更多
Impedance (Z), and phase angle (θ) of a parallel-plate capacitor with a single cherry fruit between the plates were measured using a CI meter (Chari’s Impedance meter), at 1 and 9 MHz. Capacitance C was derived from...Impedance (Z), and phase angle (θ) of a parallel-plate capacitor with a single cherry fruit between the plates were measured using a CI meter (Chari’s Impedance meter), at 1 and 9 MHz. Capacitance C was derived from Z and θ, and by using the C, θ, and Z values of a set of cherries whose moisture content (MC) values were later determined by the hot air-oven method, a calibration equation was developed. Using this equation, and their measured C, θ, and Z values, the MC of a group of cherries, not used in the calibration, was predicted. The predicted values were compared with their vacuum-oven values. The method worked well with an R2 value of 0.98 and a standard error of prediction (SEP) of 1.24, in the measured moisture range between 5% and 20%.展开更多
An electronic method to estimate the moisture content (MC) of dry fruits by measuring the impedance (Z) and phase angle (θ) of a cylindrical parallel-plate capacitor with dry fruit sample between the plates, using a ...An electronic method to estimate the moisture content (MC) of dry fruits by measuring the impedance (Z) and phase angle (θ) of a cylindrical parallel-plate capacitor with dry fruit sample between the plates, using a CI meter (Chari’s Impedance meter) at 1 and 9 MHz is described. Capacitance C was derived from Z and θ, and using the C, θ, and Z values of a set of dried cherries, whose MC values were later determined by the vacuum hot air-oven method, a calibration equation was developed. Using this equation, and their measured C, θ, and Z values, the MC of a group of cherries, not used in the calibration, was predicted. The predicted values were compared with their air-oven values. Similar predictions were done using the same method on dried blueberries. The method worked well with a good R2 value, and showed a low standard error of prediction (SEP) in the measured MC range between 5% and 30% for cherries, and 9% and 22% for blueberries.展开更多
文摘Studies were conducted on the effects of grain angle on reproducibility and accurate measurement of moisture content of four wood samples using a pin-style moisture meter. The wood samples were partitioned into four quadrants and moisture contents were measured along the grain direction in the first and second quadrants from 0 degree to 150 degrees insteps of 30 degrees. Experimental results indicated that the average moisture content remained constant as the grain angle increased. Repeated measurements of moisture content at different grain angles or points on the wood surface showed similar patterns of variation. Within-point standard deviations of the moisture contents were greater than between-point standard deviations. A non-destructive method of measuring moisture content at the same location or point on the wood surfaces could not be proposed because of the high variation of moisture content when repeated measurements were taken at the same point. Instead, accurate measurements of moisture content could be obtained at random positions within a radius of 30 mm from the point of intersection of the moisture content axis and the grain angle.
文摘Measuring the moisture content of cotton bales is an important step in controlling the quality of cotton produced and sold around the world. A non-contact microwave-based bale moisture meter, the Vomax 851-B （Vomax Instrumentation through Samuel Jackson, Lubbock, TX） has been commercially available but independent verification of these measurements has not been available. This new commercial meter was examined at a commercial facility using both laboratory produced bales and actual commercially produced bales. In the laboratory phase, bales were prepared by the Cotton Ginning Research Unit for measurement on the commercial instrument as well as by the oven reference method; the potential effects of bale orientation and bale packaging were also studied with these samples. The commercial phase involved collecting lint samples from 50 bales, over 5 days, during the 2007 ginning season. The collected bale samples were tested by the oven reference method for moisture content and those readings were compared to the microwave-based meter readings for moisture content. Moisture content, as measured, covered a wide range from 4.2% to 7.2 %, wet basis. The Vomax measurements tracked variation in bale moisture content and correlated well with the reference method; however the measurements showed higher moisture content than determined by the oven method. The Vomax 851-B shows potential to provide a reliable cotton bale moisture content for use in controlling the moisture content for commercial ginning of cotton.
文摘Impedance (Z), and phase angle (θ) of a parallel-plate capacitor with a single cherry fruit between the plates were measured using a CI meter (Chari’s Impedance meter), at 1 and 9 MHz. Capacitance C was derived from Z and θ, and by using the C, θ, and Z values of a set of cherries whose moisture content (MC) values were later determined by the hot air-oven method, a calibration equation was developed. Using this equation, and their measured C, θ, and Z values, the MC of a group of cherries, not used in the calibration, was predicted. The predicted values were compared with their vacuum-oven values. The method worked well with an R2 value of 0.98 and a standard error of prediction (SEP) of 1.24, in the measured moisture range between 5% and 20%.
文摘An electronic method to estimate the moisture content (MC) of dry fruits by measuring the impedance (Z) and phase angle (θ) of a cylindrical parallel-plate capacitor with dry fruit sample between the plates, using a CI meter (Chari’s Impedance meter) at 1 and 9 MHz is described. Capacitance C was derived from Z and θ, and using the C, θ, and Z values of a set of dried cherries, whose MC values were later determined by the vacuum hot air-oven method, a calibration equation was developed. Using this equation, and their measured C, θ, and Z values, the MC of a group of cherries, not used in the calibration, was predicted. The predicted values were compared with their air-oven values. Similar predictions were done using the same method on dried blueberries. The method worked well with a good R2 value, and showed a low standard error of prediction (SEP) in the measured MC range between 5% and 30% for cherries, and 9% and 22% for blueberries.
