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31.
Reduced protein quality is one of the concerns currently confronting the supply and utilization of wheat distillers dried grain with solubles (DDGS) as an animal feed ingredient. This study assessed the protein quality of wheat DDGS, expressed as acid detergent insoluble crude protein (ADICP) and lysine content, by blending wet distillers grain (WDG) with varying condensed distillers solubles (CDS) levels and drying using forced air convection, microwave, and microwave–convection methods. As the CDS level was increased, the protein content of wheat DDGS generated from the three drying methods increased. Interactions of CDS level with drying air temperature, microwave power, and microwave–convection settings had a significant effect (p < 0.05) on average ADICP and lysine contents. Higher ADICP and lower lysine contents were observed in samples dried at higher temperature, microwave power, and microwave convection settings. Further, the CDS level significantly affected the color parameters of microwave- and microwave–convection-dried samples and the drying air temperature–CDS level interaction significantly affected the color of forced air convection–dried samples. Significant lysine content–redness, ADICP–lightness color parameter, and ADICP–total color difference correlations were found in forced air convection–, microwave-, and microwave–convection-dried samples, respectively. Microwave and microwave–convection drying achieved desirable protein quality associated with low-temperature drying at much shorter times. 相似文献
32.
Silver-ion high-performance liquid chromatographic separation and identification of conjugated linoleic acid isomers 总被引:38,自引:21,他引:17
Najibullah Sehat Martin P. Yurawecz John A. G. Roach Magdi M. Mossoba John K. G. Kramer Youh Ku 《Lipids》1998,33(2):217-221
This is the first report of the application of silverion impregnated high-performance liquid chromatography (Ag+-HPLC) to the separation of complex mixtures of conjugated linolenic acid (CLA) isomers present in commercial CLA sources and foods and in biological specimens. This method showed a clear separation of CLA isomers into three groups related to their trans,trans, cis,trans or trans,cis, and cis,cis configuration of the conjugated double-bound system. In addition, this method separated within each geometrical isomeric group. Following Ag+-HPLC isolation, gas chromatography (GC)-electron impact mass spectrometry, and GC-direct deposition-Fourier transformed infrared spectroscopy were used to confirm the identity of two major positional isomers in the cis/trans region, i.e., Δ8,10- and Δ11,13-octadecadienoic acid, which had not been chromatographically resolved previously, Furthermore, the potential of this method was demonstrated by showing different Ag+-HPLC profiles exhibiting patterns of isomeric distributions for biological specimens from animals fed a diet containing a commerical CLA preparation, as well as for a commerical cheese product. 相似文献
33.
Recreational beaches constitute a large part of the 12 billion dollar per year tourism industry in Wisconsin. Beach closures due to microbial contamination are costly in terms of lost tourism revenue and adverse publicity for an area. Escherichia coli (E. coli), is used as an indicator of microbial contamination, as high concentrations of this organism should indicate a recent fecal contamination event that may contain other, more pathogenic, bacteria. An additional problem at many beaches in the state is the nuisance algae, Cladophora. It has been hypothesized that mats of Cladophora may harbor high concentrations of E. coli. Three beaches in Door County, WI were selected for study, based on tourist activity and amounts of algae present. Concentrations of E. coli were higher within Cladophora mats than in surrounding water. Beaches displayed an E. coli concentration gradient in water extending away from the Cladophora mats, although this was not statistically significant. Likewise, the amount of Cladophora observed on a beach did not correlate with E. coli concentrations found in routine beach monitoring samples. More work is needed to determine the impact of mats of Cladophora on beach water quality, as well as likely sources of E. coli found within the mats. 相似文献
34.
35.
Skarlicki Daniel P.; Lucas Colleen; Prociuk Terry; Latham Gary P. 《Canadian Metallurgical Quarterly》2000,41(1):69
Both theory and subject matter experts were used to generate items for a survey designed to increase understanding of why psychologists join, remain in, or leave the Canadian Psychological Association (CPA). The subject matter experts included current, former, and nonmember psychologists. 2,200 questionnaires were distributed by e-mail, and 275 were sent by surface mail. The response rates were 20% and 29% for e-mail and surface mail, respectively. Principal components analysis of the survey items resulted in 5 factors: outcomes, advocacy, organizational justice, annual convention, and professional recognition. Discriminant function analysis results showed that, on the basis of these factors, the authors were able to correctly classify respondents as current vs former members, and current vs never been members. Current members, former members, and psychologists who never joined CPA were found to differ significantly on their rating of most factors. The factors relevant for retaining members differ from those that attract psychologists to join CPA. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
The authors propose that the costs and benefits of directed forgetting in the list method result from an internal context change that occurs between the presentations of 2 lists in response to a "forget" instruction. In Experiment 1 of this study, costs and benefits akin to those found in directed forgetting were obtained in the absence of a forget instruction by a direct manipulation of cognitive context change. Experiment 2 of this study replicated those findings using a different cognitive context manipulation and investigated the effects of context reinstatement at the time of recall. Context reinstatement reduced the memorial costs and benefits of context change in the condition where context had been manipulated and in the standard forget condition. The results are consistent with a context change account of directed forgetting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
Current wrought magnesium alloys: Strengths and weaknesses 总被引:9,自引:0,他引:9
Colleen Bettles Mark Gibson 《JOM Journal of the Minerals, Metals and Materials Society》2005,57(5):46-49
The opportunities for extruded and sheet magnesium products in the automotive industry, in particular, are increasing as the
quest for lightweighting gains momentum. However, the current alloys all have limitations and these are accentuated when higher
productivity targets are also imposed. This article attempts to summarize the strengths and weaknesses of the current wrought
alloys, with particular emphasis on the extrusion process, and also considers alternative processing routes which may be useful
in overcoming some of these shortcomings.
For more information, contact Colleen Bettles, CMIT Private Bag 33, Clayton South MDC, Clayton Victoria 3169, Australia; +61-3-95452936;
fax +61-3-95441128; e-mail Colleen.Bettles@csiro.au. 相似文献
38.
The problem of finding the shape of a perfectly conducting cylinder when illuminated by an E-polarized incident electromagnetic wave is considered. The given problem is cast in the form of a penalized optimization problem in which we seek a surface in some suitably constrained class which minimizes a functional involving two terms. The first term measures the mean square deviation of the far field of the solution to the direct scattering problem for a surface in the admissible class from given, measured, far field data whilst the second term, penalty, measures the error in satisfying the imposed boundary conditions. An optimisation algorithm is used which does not require that a direct problem be solved in the updating process. Explicit reconstructions are presented which illustrate the effectiveness of the method. Some results indicating the sensitivity of the algorithm to the choice of penalty parameter and the number of incident waves are also given. 相似文献
39.
Colleen Wade Michael Spearpoint Charles Fleischmann Greg Baker Anthony Abu 《Fire Technology》2018,54(4):893-920
There is an increasing desire to use more engineered timber products in buildings, due to the perceived aesthetics of timber and desire for more sustainable architecture. However, there are concerns about fire performance of these products especially in taller buildings. This has led to renewed research to understand the behaviour of timber surfaces in compartments exposed to fire. This paper describes a two-zone calculation model for determining the fire environment within a compartment constructed from timber products where varying amounts of timber are exposed on the walls and ceiling. A set of eight full-scale compartment experiments previously reported in the literature are used to assess the capability of the model. The fire load energy density in the experiments ranged from 92 MJ/m2 to 366 MJ/m2 comprising either wood cribs or bedroom furniture with the largest compartment having dimensions 4.5?×?3.5?×?2.5 m high with an opening 1.069 m wide?×?2.0 m high. The experiments were ventilation-controlled. It is shown that the model can be used to provide conservative predictions of the fire temperatures for compartments with timber exposed on the walls and/or ceiling as part of an engineering analysis. There are several limitations that are discussed including the need to consider the debonding of layers in the case of cross-laminated timber. It is recommended that further benchmarking of the model be done for different ventilation conditions and with engineered timber products where debonding does not occur. This will test the model under a wider range of conditions than examined in this paper. 相似文献
40.
The aim of this research was to exploit the chemical properties of natural products to control the incidence and extent of mould growth in houses. The screening of antimould activities of seven essential oil extracts showed that most of the extracts completely inhibited the growth of all three test mould at the concentration of 1% w/v on nutrient medium, whereas, different fractions of manuka oil showed varied activity. Subsequently, using both mycological and scanning electron microscopy, the testing of selected extracts on two different types of gypsum board finished with either paint or wall-paper, confirmed the antimould activity of eugenol, thymol and cinnamaldehyde against Penicillium corylophilum. This study identified certain essential oil extract as a potential mould inhibitor for panel products which is one of the most common mould habitats in the building environment. Mould growth in residential houses is a major concern and chemical fungicides commonly used to control the growth of mould are not often appropriate for indoor applications. Natural alternatives such as essential oils are desirable for this application. Knowledge gained through this research should lead to new niche panel product development to create healthier housing. 相似文献