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81.
The selectivity of hexane isomers towards cottonseed pigments and colour fixed pigments was illustrated by using spectrophotometric analysis of crude, refined and bleached oils, and by refinability and bleachability criteria. Crude cottonseed oil contains besides the alkali-refinable gossypol and gossypurpurin, several colour fixed pigments. Anhydrogossypol, gossyfulvin, anthocyanins and carotenoids seem to be responsible for the colour-fixation of the oil. Only carotenoids are eliminated by bleaching. Selectivities of hexane isomers towards colour fixed pigments are in the following order: isohexane < n-hexane < cyclohexane < benzene < methylcyclopentane. 相似文献
82.
Effects of native microflora (NM) on growth kinetics of Salmonella Enteritidis strain 04-137 were studied in raw ground chicken. First, samples of ground chicken with high and low levels of NM (10(7.1) and 10(4.9) CFU/g, respectively) were spiked with Salmonella at doses ranging from 10(1) to 10(4) CFU/g. The growth kinetics, including the rate constant of growth, r, and the lag period, were similar, but the maximum cell level, N(max), was higher at higher initial Salmonella doses for both NM levels. Second, samples of ground chicken with high and low NM levels (10(6.8) and 10(4.7) CFU/g, respectively) were spiked with Salmonella and then stored at various constant temperatures ranging from 8 to 32°C. Both N(max) and r for Salmonella were higher at higher temperatures for both NM levels. Although r for total bacteria, which consisted of NM and Salmonella, was also higher at higher temperatures, N(max) was constant at all temperatures for both NM levels. Further, Salmonella growth was compared among samples of ground chicken with high and low NM levels and samples of sterilized chicken. Salmonella growth, characterized by both N(max) and r, was highest in sterilized chicken, followed by chicken with the low NM level. Our growth model successfully described and analyzed the growth of Salmonella and total bacteria in chicken at constant temperatures; using the data obtained, the model also successfully predicted the growth of Salmonella and total bacteria in chicken stored at dynamic temperatures. Our study clarified the effects that different doses of NM in ground chicken had on the growth kinetics of the Salmonella strain and demonstrated the usability of the growth model for foods with NM. 相似文献
83.
J Mazuch I Cupka P Bruncák K Géc J Pelc L Machan M Zaher 《Canadian Metallurgical Quarterly》1996,97(4):220-223
The authors evaluated the results after classical (CCHE) and laparoscopic cholecystectomies (LCHE) in the period from March 16 1994 to June 30 1995. In this period they operated on 408 patients, out of which 208 were operated by the laparoscopic technique. There were no differences in postoperative morbidity. The mortality after laparoscopic surgery was 0% and the classical cholecystectomy reached the morbidity of 1.4%. Complicated patients were usually operated in the classical way. The time of hospitalisation after LCHE was 5.2 days and after CCHE 8.3 days. The results of LCHE were as follows: morbidity 10.5%, conversions 2.4%, reoperations 1.4%, and no leakage of the bile duct. We saved 40% of costs using LCHE. All these facts show that LCHE is advantageous, secure and well tolerated by patients. The patients prefer comfort after the operation, good cosmetic effect and a short hospital isation. CCHE did not lose its position, especially in complicated cases. (Tab. 5, Ref. 21.) 相似文献
84.
Catterson V.M. McArthur S. Judd M.D. Zaher A.S. 《Power Delivery, IEEE Transactions on》2008,23(4):1754-1762
The volume of data produced by existing partial discharge monitoring systems is often too large for engineers to examine in detail, leading to data being ignored and useful indicators of health being missed. The case study reported in this paper recorded 21thinspace839 events around an HVDC reactor over a six-day period. We estimate that it takes 1 min to check whether an event requires detailed study, leading to over two man-months of effort to locate important events in a dataset of this size. Additionally, online monitoring data are stored onsite, and may require an engineer's visit for collection. This paper presents an approach to remote partial discharge monitoring, supported by automated data interpretation and prioritization, which enables engineers to remotely find and download important data. Results from the case study are used to illustrate these concepts. 相似文献
85.
Synthesis,characterization, and ligating behavior of poly[N,N‐p‐phenylene bisacryl (methacryl)amide]
Monomers of diacylated amine were synthesized by the reaction of acryloyl chloride or methacryloyl chloride with p‐phenylenediamine. Heating DMF solution of these monomers at 75°C in the presence of AIBN as an initiator gave the corresponding polymer. The solid metallopolymer complexes with different metal salts were isolated either by the in situ addition of the monomer, metal salt, and initiator at 75°C or by the reaction of the isolated polymer with the metal salt at 150°C. The monomers, polymers, and their metallopolymer compounds were characterized using elemental analysis, IR, NMR (1H and 13C), and MS spectral measurements in addition to thermal analysis. The IR data showed that the coordinating atoms of the polymer are dependent on the reaction temperature. The ion selectivity of the isolated polymers toward different metal ions either for a single metal ion or in a mixture as aqueous solutions are studied by the batch techniques. Energy dispersive spectroscopy (EDS) measurements showed that both polymers are more selective to Hg2+ and Pb2+. The morphology of the polymers and their metallopolymer complexes at different temperature was also studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2412–2422, 2006 相似文献
86.
Malignant tumors contrast with benign ones in their ability to invade adjacent tissue and to metastasize. The urokinase plasminogen activator is a proteolytic enzyme that can facilitate these processes. In many carcinomas, the concentration of the urokinase plasminogen activator system is high. The high expression of these enzymes is related to tumor grade. In this study, we have investigated whether secretion of the urokinase plasminogen activator, urokinase plasminogen activator receptor, and plasminogen activator inhibitor 1 in normal kidney tissue and kidney cancer tissue follows this pattern. We have found that urokinase plasminogen activator, urokinase plasminogen activator receptor, and plasminogen activator inhibitor 1 were expressed in higher levels in kidney cancers (squamous cell carcinoma and renal cell carcinoma) than in normal kidney tissue and that these differences were statistically significant (P < or = 0.05). In renal cell carcinomas, we have observed differences between normal kidney tissue and renal cell carcinomas in males and Caucasians but not in females and African Americans (P < or = 0.05). Expression of the urokinase plasminogen activator system was also higher in grade III tumors when compared with lower-grade tumors or normal tissue. 相似文献
87.
Lina Al‐Kanj Wissam El‐Beaino Ahmad M. El‐Hajj Zaher Dawy 《Wireless Communications and Mobile Computing》2016,16(12):1537-1555
Energy is becoming a main concern nowadays due to the increasing demands on natural energy resources. Base stations (BSs) consume up to 80% of the total energy expenditure in a cellular network. In this paper, we propose and evaluate a green radio network planning approach by jointly optimizing the number of active BSs and the BS on/off switching patterns based on the changing traffic conditions in the network in an effort to reduce the total energy consumption of the BSs. The problem is formulated as an integer optimization problem, which proves to be NP‐complete, and thus it can be efficiently solved for small to medium network sizes. For large network sizes, we propose a heuristic solution with close to optimal performance because the optimal solution becomes computationally complex. Planning is performed based on two approaches: a reactive and a proactive approach. In the proactive approach, planning will be performed starting with the lowest traffic demand until reaching the highest traffic demand, whereas in the reactive approach, the reverse way is considered. Performance results are presented for various case studies and are complemented by testing the proposed approaches using commercial radio network planning tools. Results demonstrate considerable energy savings reaching up to 40% through dynamic adaptation of the number of simultaneously active BSs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
88.
Hao-Yu Shen Li-Yan Ying Hai-Liang Jiang Zaher M. A. Judeh 《International journal of molecular sciences》2007,8(6):505-512
The selective oxidation of alcohols with molecular oxygen was efficiently completed in high conversion and selectivity using copper-bisisoquinoline-based catalysts under mild reaction condition. The effects of various parameters such as reaction temperature, reaction time, oxidant, ligands, etc, were studied. Solvent effect has been as well studied in ionic liquids [bmim]PF6, [omim]BF4 and [hmim]BF4, comparing to traditional volatile organic solvent. The use of ionic liquids was found to enhance the catalytic properties of the catalysts used. 相似文献
89.
U Zaher M S Moussa I N Widyatmika P van Der Steen H J Gijzen P A Vanrolleghem 《Water science and technology》2006,54(4):129-137
The observed acclimatisation to biodegradable toxicants in anaerobic cassava wastewater treatment is explained by modelling anaerobic cyanide degradation. A complete degradation pathway is proposed for cyanide. Cyanide degradation is modelled as enzymatic hydrolysis to formate and ammonia. Ammonia is added to the inorganic nitrogen content of the digester while formate is degraded by the hydrogenotrophic methanogens. Cyanide irreversible enzyme inhibition is modelled as an inhibition factor to acetate uptake processes. Cyanide irreversible toxicity is modelled as a decay factor to the acetate degraders. Cyanide as well as added phosphorus buffer solution were considered in the chemical equilibrium calculations of pH. The observed reversible effect after acclimatisation of sludge is modelled by a population shift between two aceticlastic methanogens that have different tolerance to cyanide toxicity. The proposed pathway is added to the IWA Anaerobic Digestion Model no.1 (ADM1). The ADM1 model with the designed extension is validated by an experiment using three lab-scale upflow anaerobic sludge bed reactors which were exposed to different cyanide loadings. 相似文献