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1.
Wajih N. Sawaya Muhammad Ayaz Jehangir K. Khalil Abdallah F. Al-Shalhat 《Food chemistry》1985,18(1):35-45
The chemical composition and nutritional quality of tehineh, a paste of dehulled roasted sesame seeds, from Saudi Arabia and other countries, were studied. Results showed 24.7% protein, 58.9% fat, 2.3% fiber, 3.0% ash and <1.0% moisture. The tehineh contained relatively high amounts (mg/100 g) of P (692), Mg (362), Fe (7.19), Cu (1.96), Mn (1.46) and Zn (7.82) and low amounts of Ca (61) and Se (0.05). Gas-liquid chromatography (GLC) analysis of the oil revealed percentages of 42.4 for oleic, 39.7 for linoleic, 9.8 for palmitic and 6.4 for stearic acid. Lysine was the only limiting amino acid with a chemical score of 64, while the sulphur-containing amino acids (methionine + cystine) and tryptophan were present in amounts exceeding the requirement of the FAO/WHO (1973) reference protein. The in vitro protein digestibility (IVPD) value of 83.3% and the calculated protein efficiency ratio (C-PER), 2.14, were slightly higher than those of sesame seeds and both values were lower than the IVPD and C-PER of 90.0% and 2.50, respectively, for ANRC casein. 相似文献
2.
The Inter-laboratory Comparison Programme (ILCP) is a quality assurance system administered by the Dairy Division of the Ministry of Agriculture and Fisheries to monitor the performance of agency certified laboratories (ACLs). The programme works on a monthly basis during the milk producing season and is co-ordinated from the National Dairy Laboratory (NDL). Samples are despatched to Regional Dairy Labora-tories (RDL) and to the ACLs 2 weeks later. The RDL results are used to calculate an official mean. The ACL results are sent to the RDL where they are scrutinized immediately; hence, a rapid feedback on the ACL performance is possible. The NDL despatches a detailed statistical evaluation of results of ACLs and RDLs. The pro-gramme has increased from seven products in 1977 to eleven in 1984. Microbiological and chemical analyses are performed. A bacterial identification scheme to monitor E. coli and S. aureus was included in 1982. A scoring system (0 poor-10 good) which includes a weighting for specific tests and which is measured against an 'official' score has been introduced into a report which is distributed to all participants. The data generated by the programme are used by both ACLs and RDLs to check their analytical performance and quality control. Data are used by Dairy Division, as a national compilation of results issued by it which serves to highlight problem analyses, season trends and analytical limits. 相似文献
3.
M J Scotter S A Thorpe S L Reynolds L A Wilson D J Lewis 《Food Additives & Contaminants》1992,9(3):237-242
Retail samples of livers from calf (23), ox (18), lamb (17), pig (15), chicken (16) and turkey (1) were analysed to determine levels of vitamin A (all trans-retinol) and to aid assessment of the effects of using vitamin supplemented compound feedingstuffs for livestock. For comparison, 22 liver samples from lambs reared on diets not containing vitamin-supplemented compound feedingstuffs and four samples of liver from ox which had received supplemented feed but not during the last four months prior to slaughter were also analysed. The chosen method of analysis utilized saponification, solvent extraction and normal-phase high performance liquid chromatography with fluorescence detection. For all species analysed, the levels of vitamin A ranged from 10 to 1100 mg/kg, with all but seven at or below 400 mg/kg. For lamb and ox livers, the mean levels were 310 mg/kg and 200 mg/kg respectively for retail samples. The mean levels were 220 mg/kg (lamb) and 120 mg/kg (ox) in liver samples from animals fed controlled diets. The results are of the same order as those reported over recent years. 相似文献
4.
《Food Control》2006,17(10):776-780
Organisms of the Mycobacterium tuberculosis complex (TBC) are responsible for tuberculosis, a chronic disease which represents a serious public health problem in the world. The most common means of contracting the disease are through inhalation of aerosols, drinking of unpasteurised milk from an infected cow and the sharing of common water or feed sources.In this study a rapid, sensitive and reliable PCR-based method for specific detection of the Mycobacterium TB complex directly from raw milk samples was developed. The DNA extraction method was effective and able to remove inhibitors and allowed the isolation of amplifiable DNA. The procedure demonstrated the presence of the TBC mpb70 gene in 36/50 (72%) of Albanian milk samples tested. The study highlights the need to screen extracommunitarian milk to define an epidemiological background and to guarantee the quality of the raw milk in countries lacking a suitable TB-infection control plan. 相似文献
5.
Granular S, finely-ground S, iron sulphate and aluminium sulphate were added at two rates to the surface (0–6 cm) of a soil and acidification and leaching of nutrients were measured over 12 months in a laboratory study. Iron and aluminium sulphate both rapidly lowered soil pH in the top 0–6 cm of the soil. There was little difference in soil pH after 3 and 12 months reaction of these two amendments. In contrast, for granular S and finely-ground S there were clear decreases in soil pH between 3 and 12 months reaction with the soil. Finely-ground S was oxidized in the soil faster than granular S and therefore had a more acidifying effect. The top 0–6 cm of the soil was acidified by all the agents used but the deeper soil was less affected. The only treatments which lowered the pH of the 12–18 cm layer below pH 6 were the high rates of iron and aluminium sulphate. Soil acidification resulted in a decrease in exchangeable Ca, Mg and K, an increase in exchangeable Al and a decrease in effective CEC in the acidified soil layers.At both levels of addition, total ionic strength of percolates from the soil followed the order: aluminium sulphate = iron sulphate > finely gound S > granular S > control and was higher at the higher rate of addition. The pH values of percolates followed the order: control > granular S > finely ground S > iron sulphate = aluminium sulphate and were lower at the higher rate of addition. For the amended soils there was a very close relationship between the pattern and total amounts of SO
4
2-
and Ca2+ leached.It was concluded that granular S is not an effective acidifying agent since it is oxidized very slowly in the soil and that acidfying agents should be incorporated to the depth that acidification is required. 相似文献
6.
Image mosaic construction is about stitching together a number of images about the same scene to construct a single image with a larger field of view. The majority of the previous work was rooted at the use of a single image-to-image mapping termed planar homography for representing the imaged scene. However, the mapping is applicable only to cases where the imaged scene is either a single planar surface, or very distant from the cameras, or imaged under a pure rotation of the camera, and that greatly limits the range of applications of the mosaicking methods. This paper presents a novel mosaicking solution for scenes that are polyhedral (thus consisting of multiple surfaces) and that are pictured possibly in closed range of the camera. The solution has two major advantages. First, it requires only a few correspondences over the entire scene, not correspondences over every surface patch in it to work. Second, it conquers a seemingly impossible task—warping image data of surfaces that are visible in only one of the input images, which we refer to as the singly visible surfaces, to another viewpoint to constitute the mosaic there. We also provide a detail analysis of what determines whether a singly visible surface could be mosaicked or not. Experimental results on real image data are presented to illustrate the performance of the method. 相似文献
7.
Contaminant intrusion in a water distribution network is a complex but a commonly observed phenomenon, which depends on three elements – a pathway, a driving force and a contamination source. However, the data on these elements are generally incomplete, non-specific and uncertain. In an earlier work, Sadiq, Kleiner, and Rajani (2006) have successfully applied traditional Dempster–Shafer theory (DST) to estimate the “risk” of contaminant intrusion in a water distribution network based on limited uncertain information. However, the method used for generating basic probability assignment (BPA) was not very flexible, and did not handle and process uncertain information effectively. In this paper, a more pragmatic method is proposed that utilizes “soft” computing flexibility to generate BPAs from uncertain information. This paper compares these two methods through numerical examples, and demonstrates the efficiency and effectiveness of modified method. 相似文献
8.
It has been confirmed that adult virgin females ofAnthrenus sarnicus Mroczkowski exhibit a characteristic headstand posture that is associated with the release of a sex pheromone. Volatiles trapped on filter papers suspended above calling females were attractive to adult virgin males when tested in a two-choice target bioassay. Separate aeration extracts of males and females were analyzed by gas chromatography-mass spectrometry and showed that decanol and decyln-butyrate were released by females only. These components were present in approximately equal amounts and accounted for about 90% of the total area of the chromatogram. Decyl butyrate produced an electroantennogram response with a larger response from males than females. Behaviorally, a mixture of 10g of decanol and 10g of decyl butyrate attracted 88% of males and 10g of decyl butyrate alone attracted 82% of males in the bioassay. The role of decyl butyrate as a sex pheromone is convincing, but this is not the case for decanol. 相似文献
9.
《Materials Research Bulletin》2006,41(12):2268-2275
Porous hollow silica nanoparticles (PHSNs) were prepared and applied as controlled delivery system of water-soluble pesticide validamycin. PHSNs were loaded with validamycin through a specially designed supercritical fluid loading method. It was demonstrated that a high loading capacity (36 wt.%) of validamycin could be achieved, which was found to be more effective than that of the simple immersing method in this study. The loaded PHSNs were characterized by TG, IR and XPS analysis. The validamycin release profile from PHSNs was investigated and showed a multi-staged release pattern probably due to the different adsorption locations of validamycin on PHSNs. This release behavior makes PHSNs a promising carrier in agriculture, especially for pesticide controlled delivery whose immediate as well as prolonged release is needed. In addition, factors influencing the validamycin release rate, including pH and temperature, were investigated. 相似文献
10.
《Chemical engineering science》1986,41(12):3205-3212
Pressure gradients were generated during counter-diffusion of adsorbing gases within pelletized activated carbon pellets and modified molecular-sieving carbon pellets even though external isobaric conditions were maintained. Such non-isobaric phenomena were analysed with a zone reaction model which incorporated a flow equation, adsorption equilibrium relationships of gases, and adsorption rates. It was found that pressure gradients are induced within the porous solids by differences in diffusion rates, adsorptivities and adsorption rates of the counter-diffusing gases. 相似文献