Accuracy of subsampling mill for granular materials

A subsampling mill was constructed with 19 subsample spouts similar to the 1 or 2 subsample spouts on the conventional subsampling mills. Samples of peanuts, each of which contained 1 kernel made radioactive by neutron activation, were comminuted in the mill. For treatment M the discharge from each spout was kept separate. For treatment R, the discharge from all 19 spouts was blended together in a twin-shelled blender and subdivided with a riffle divider into 16 subsamples which averaged the same weight as the M subsamples. Radioactivity counts/gram of each subsample were measured. Eleven samples were comminuted for each treatment which produced a total of 209 M samples and 176 R samples. An analysis of variance on the pooled data from each treatment showed a mean square error of 1318.3 for the M treatment and 1278.6 for the R treatment. The null hypothesis that the mean square errors for the two treatments are equal was not rejected by the F test (P=0.421).     

Bright greenish-yellow fluorescence and aflatoxin in recently harvested yellow corn marketed in north carolina

Corn kernels that exhibited bright greenish-yellow fluorescence (BGYF) under long-wave ultraviolet light were hand-picked from samples of yellow corn produced in eastern North Carolina. The BGYF kernels from 113 4-kg samples contained an average of 8665 parts per billion (ppb) aflatoxin compared to an average of 46 ppb in the non-BGYF kernels. A regression analysis between the ppb aflatoxin concentration and the wt % BGYF kernels in 2,304 4.5-kg samples produced the regression equation: ppb in sample =197 (wt % BGYF). The correlation coefficient for the analysis was 0.90. Testing programs to reduce aflatoxin concentrations in purchased lots of corn based on either the BGYF method or the AOAC chemical assay method were compared. The average aflatoxin concentration in lots accepted by the AOAC method was 4 ppb, 10 ppb or 18 ppb when an acceptance level of < 20 ppb, < 50 ppb or < 100 ppb, respectively, was used. For the BGYF method, the average aflatoxin concentration in accepted lots was 10 ppb, 16 ppb or 22 ppb when an acceptance level of < 0.10% BGYF, < 0.25% BGYF or < 0.50% BGYF, respectively, was used. Approximately the same percentage of lots were accepted by both methods when either the low, medium or high acceptance level was used. Paper no. 6930 of the Journal Series of the North Carolina Agriculture Research Service (NCARS), Raleigh, NC.     

Higher-order nonlinear priors for surface reconstruction

For surface reconstruction problems with noisy and incomplete range data, a Bayesian estimation approach can improve the overall quality of the surfaces. The Bayesian approach to surface estimation relies on a likelihood term, which ties the surface estimate to the input data, and the prior, which ensures surface smoothness or continuity. This paper introduces a new high-order, nonlinear prior for surface reconstruction. The proposed prior can smooth complex, noisy surfaces, while preserving sharp, geometric features, and it is a natural generalization of edge-preserving methods in image processing, such as anisotropic diffusion. An exact solution would require solving a fourth-order partial differential equation (PDE), which can be difficult with conventional numerical techniques. Our approach is to solve a cascade system of two second-order PDEs, which resembles the original fourth-order system. This strategy is based on the observation that the generalization of image processing to surfaces entails filtering the surface normals. We solve one PDE for processing the normals and one for refitting the surface to the normals. Furthermore, we implement the associated surface deformations using level sets. Hence, the algorithm can accommodate very complex shapes with arbitrary and changing topologies. This paper gives the mathematical formulation and describes the numerical algorithms. We also show results using range and medical data.     

Sodium oxacillin in the horse: serum, synovial fluid, peritoneal fluid, and urine concentrations after single-dose intramuscular administration

Six healthy adult mares were given a single dose (25 mg/kg of body weight) of sodium oxacillin IM. Oxacillin concentrations in serum, synovial fluid, peritoneal fluid, and urine were measured serially over a 48-hour period. The mean peak serum oxacillin concentration was 9.75 microgram/ml at 0.5 hour after injection. Mean peak oxacillin concentrations in synovial and peritoneal fluids were 1.45 microgram/ml and 2.60 microgram/ml at 1 hour and 2 hours, respectively. These concentrations decreased in parallel with serum values and were not measurable at 48 hours. Urine concentrations of oxacillin were high, with a mean peak concentration of 2,790.2 microgram/ml at 0.5 hour.     

Comparison of the observed distribution of aflatoxin in shelled peanuts to the negative binomial distribution

Suitability of the negative binomial distribution for use in estimating the probabilities associated with sampling lots of shelled peanuts for aflatoxin analysis has been studied. Large samples, called “minilots,” were drawn from 29 lots of shelled peanuts contaminated with aflatoxin. These minilots were subdivided into ca. 12 lb samples which were analyzed for aflatoxin. The mean and variance of these aflatoxin determinations for each minilot were determined. The shape parameterk and the mean aflatoxin concentrationm were estimated for each minilot. A regression analysis indicated the functional relationship betweenk andm to be:k=(2.0866+2.3898m) × 10⁻⁶. The observed distribution of sample concentrations from each of the 29 minilots was compared to the negative binomial distribution by means of the Kolmogorov-Smirnov test. The null hypothesis that each of the true unknown distribution functions was negative binomial was not rejected at the 5% significance level for all 29 comparisons. Journal Series Paper of the North Carolina State University Agricultural Experiment Station, Raleigh, N.C.     

The transport equations for multi-phase systems

A rigorous theoretical treatment of the transport equations is presented for multi-phase systems. The results have application in the analysis of a variety of processes including liquid—liquid extraction, gas—liquid mass transfer, and chemical reaction and dispersion in multi-phase systems. The case of mass transfer is examined in detail.