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91.
Puffing or popping is a common method of processingAmaranthus cruentus (Syn.Amaranthus paniculatus L. or Rajgeera) grain. Investigations into the effect of this processing treatment have shown the percent unsaturation in
the oil to decrease from 75.5% to 62.3%. The maximum effect is on linoleic acid, the quantity of which decreased sharply from
46.8% to 27.0%. Squalene also increased by 15.5%, due to puffing of amaranth seeds. 相似文献
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Sandip B. Bankar Mahesh V. Bule Rekha S. Singhal Laxmi Ananthanarayan 《Food and Bioprocess Technology》2009,2(4):344-352
A number of nutritional factors influencing glucose oxidase (EC 1.1.3.4) production by Aspergillus niger NCIM 545 were studied. The synthesis of glucose oxidase by A. niger was investigated in two steps using submerged fermentation at 30 ± 2 °C and 180 rpm for 96 h. Primarily, nutritional components
were selected by one-factor-at-a-time method, and the significance of each component with respect to glucose oxidase production
was identified by Plackett–Burman design (seven variables including six nutritional viz. sucrose, sodium nitrate, peptone,
calcium carbonate, magnesium sulfate, and potassium dihydrogen phosphate, and one dummy or unassigned variable were studied
with eight experiments). In the second step, concentration of most significant factors and their interaction were studied
with response surface methodology (central composite design). Each variable in the design was studied at five different levels,
with all variables taken at a central coded value of zero. Considerable amount of glucose oxidase was produced from A. niger species with sucrose as the carbon source, sodium nitrate as the inorganic nitrogen source, and peptone as the organic nitrogen
source. Glucose oxidase activity increased remarkably by 28.93 fold (from 0.00993 to 0.29 U ml−1) with CaCO3-supplemented media. The outcome of Plackett–Burman design showed CaCO3, peptone, and MgSO4 as significant parameters. Further optimization using a three-factor central composite design with 20 experiments increased
yield of glucose oxidase from 0.29 to 2.05 U ml−1 (sevenfold) with a decrease in cultivation time from 96 to 72 h. 相似文献
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Amit Kumar Rajendra Prasad Badoni Shailey Singhal Shilpi Agarwal Amitabh Raj Tripathi 《Chemical Engineering Communications》2018,205(1):92-101
Sulfated zirconia is a very strong solid acid catalyst which can be utilized for various reactions. The present study focuses on synthesis of zirconia-based catalyst with high acidity and high surface area, particularly for isomerization reaction. Sulfated zirconia has been obtained by sulfation of zirconia prepared by hydrothermal route. The catalyst was developed by impregnating tungstophosphoric acid on sulfated zirconia by wet incipient method. The catalyst was characterized through Brunauer–Emmett–Teller (BET) surface area, temperature-programmed desorption of ammonia, temperature program reduction of hydrogen, Fourier transmission infrared spectroscopy, and thermogravimetric analysis. The results revealed that the catalyst is crystalline in nature with surface area 190–225?m2 g?1 and acidity 0.135–0.558?mmol?g?1. Twenty-five percent conversion was obtained (as confirmed by gas chromatography) at 225°C using n-hexane as model hydrocarbon in fixed-bed microreactor. 相似文献
96.
This paper describes data mining and data warehousing techniques that can improve the performance and usability of Intrusion
Detection Systems (IDS). Current IDS do not provide support for historical data analysis and data summarization. This paper
presents techniques to model network traffic and alerts using a multi-dimensional data model and star schemas. This data model was used to perform network security analysis and detect denial of service attacks. Our data model can also
be used to handle heterogeneous data sources (e.g. firewall logs, system calls, net-flow data) and enable up to two orders
of magnitude faster query response times for analysts as compared to the current state of the art. We have used our techniques
to implement a prototype system that is being successfully used at Army Research Labs. Our system has helped the security
analyst in detecting intrusions and in historical data analysis for generating reports on trend analysis.
Recommended by: Ashfaq Khokhar 相似文献
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BACKGROUND/AIMS: International comparisons of clinical practice may help in assessing the magnitude and possible causes of variation in cross national healthcare utilisation. With this aim, the indications for cataract surgery in the United States, Denmark, the province of Manitoba (Canada), and the city of Barcelona (Spain) were compared. METHODS: In a prospective multicentre study, patients scheduled for first eye cataract surgery and aged 50 years or older were enrolled consecutively. From the United States 766 patients were enrolled; from Denmark 291; from Manitoba 152; and from Barcelona 200. Indication for surgery was measured as preoperative visual status of patients enlisted for cataract surgery. Main variables were preoperative visual acuity in operative eye, the VF-14 score (an index of functional impairment in patients with cataract) and ocular comorbidity. RESULTS: Mean visual acuity were 0.23 (USA), 0.17 (Denmark), 0.15 (Manitoba), and 0.07 (Barcelona) (p < 0.001). When restricting the sample to eyes with normal retina and macula, no significant difference between United States and Denmark was observed (p > 0.05). Mean VF-14 scores were 76 (USA), 76 (Denmark), 71 (Manitoba), and 64 (Barcelona) (p < 0.001). CONCLUSION: Similar indications for cataract surgery were found in the United States and Denmark. Significantly more restricted indications were observed in Manitoba and Barcelona. Possible explanations for the results are discussed, including differences in sociodemographic characteristics, access to care, surgeons' willingness to operate, and patient demand. 相似文献