Please use this identifier to cite or link to this item: http://localhost:80/xmlui/handle/123456789/16239
Title: Design of a microbial contamination detector and analysis of error sources in its optical path
Authors: Zhang, Chao
Yu, Xiang
Liu, Xingju
Zhang, Lei
Keywords: Microbial contamination detection
spectrophotometric method
Light splitting unit
wavelength error analysis
Issue Date: 9-May-2014
Publisher: Karachi: Faculty of Pharmacy & Pharmaceutical Sciences University of Karachi
Citation: Zhang, C., Yu, X., Liu, X., & Zhang, L. (2014). Design of a microbial contamination detector and analysis of error sources in its optical path. Pakistan Journal of Pharmaceutical Sciences, 27.
Abstract: Microbial contamination is a growing concern in the food safety today. To effectively control the types and degree of microbial contamination during food production, this paper introduces a design for a microbial contamination detector that can be used for quick in-situ examination. The designed detector can identify the category of microbial contamination by locating its characteristic absorption peak and then can calculate the concentration of the microbial contamination by fitting the absorbance vs. concentration lines of standard samples with gradient concentrations. Based on traditional scanning grating detection system, this design improves the light splitting unit to expand the scanning range and enhance the accuracy of output wavelength. The motor rotation angle φ is designed to have a linear relationship with the output wavelength angle λ, which simplifies the conversion of output spectral curves into wavelength vs. light intensity curves. In this study, we also derive the relationship between the device’s major sources of errors and cumulative error of the output wavelengths, and suggest a simple correction for these errors. The proposed design was applied to test pigments and volatile basic nitrogen (VBN) which evaluated microbial contamination degrees of meats, and the deviations between the measured values and the pre-set values were only in a low range of 1.15% - 1.27%.
URI: http://142.54.178.187:9060/xmlui/handle/123456789/16239
ISSN: 1011-601X
Appears in Collections:Issue No.3 (Supplementary)

Files in This Item:
File Description SizeFormat 
SUP-9.htm129 BHTMLView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.