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11.
BFe30-1-1白铜管早期腐蚀失效原因分析 总被引:2,自引:0,他引:2
某电厂凝汽器BFe30-1-1白铜管投运后几年内出现较为严重的局部腐蚀和点腐蚀,为此,对材质、水质等诸多因素进行了分析研究,通过宏观、微观检查和电化学试验,认为是微生物及生物粘泥的附着引起了铜管的早期腐蚀失效。 相似文献
12.
Interviews with African American and White American elders capture the immediate power of the Brown v. Board of Education (1954) decision and the biography of its impact over time. This article reviews the lived experience of the decision and theorizes 3 threats to sustainability that ruthlessly undermined the decision over time: (a) the unacknowledged and enormous sacrifice endured by the African American community in the name of desegregation; b) the violent and relentless resistance to the decision by government officials, educators, and many White community members; and (c) the dramatic shrinkage of the vision of Brown from the dismantling of White supremacy to a technical matter of busing. Implications are drawn for the study of desegregation and for the study of sustainability of social justice more broadly. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Psychologists' work was cited in the Supreme Court case of Brown v. Board of Education (1954). One criticism of the citation was that psychology could be used to overturn the Brown decision and return the country to segregation. A historical examination of such an attempt to overturn Brown in the early 1960s on the basis of new psychological knowledge shows that psychology was not persuasive in the face of the civil rights movement. The failure of segregationists to overturn Brown with psychological experts underscores how psychology is ineluctably bound to the larger society. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
Mohammed Aider Djamel Djenane Wassef B. Ounis 《International Journal of Food Science & Technology》2012,47(5):1028-1036
Amino acid composition, protein hydrophobicity, foaming and emulsifying properties of mustard protein isolate at pH 3, 5, 7 and in 0.05 and 0.1 m NaCl were studied. Glutamic (19.18 ± 0.30%) and aspartic (7.49 ± 0.11%) acids were the dominants. Foaming ability was enhanced by NaCl. Time to reach 75 mL foam was 23% higher in water than in NaCl. Drained volume after 10 min was concentration dependent and was the lowest in 0.05 and 0.1 m NaCl at protein concentration of 2.5% and 5%. The emulsifying properties were pH and concentration dependent, and the best results were obtained at pH 3, corresponding to the highest positive charge density of the protein surface. The highest emulsion stability (90.22 ± 3.52%) was obtained in 0.05 m NaCl and 5% protein concentration, whereas the lowest (63.00 ± 1.06%) was in water at all protein concentrations. Protein hydrophobicity was low and depended of pH but not of NaCl. 相似文献
15.
Thapakorn Chumphon Kanjana Pangjit Saran Promsai 《International Journal of Food Science & Technology》2021,56(5):2182-2192
This study found that the isolated probiotics Lactobacillus paracasei KUKPS6201, L. acidophilus KUKPS6107, L. reuteri KUKPS6103, L. rhamnosus KUKPS6007, L. salivarius KUKPS6202, Bacillus coagulans KPSTF02 and Saccharomyces boulardii KUKPS6005 had high potential for probiotic properties. All strains had antibacterial activity and high antioxidant activity of 1.654 ± 0.017 mg Trolox mL−1 probiotic extract. The selected strains could survive in a simulated gastrointestinal tract under anaerobic conditions and showed no haemolytic activity. Furthermore, the probiotic strains were strongly auto-aggregated and also showed co-aggregated ability with pathogenic bacteria. The probiotic microorganisms demonstrated high ability to adhere to Thai-pigmented rice grains. The results of analysis of these probiotics showed that Riceberry rice bran oil was an excellent prebiotic. A synbiotic product containing Thai-pigmented rice grains (cultivar Riceberry, Luem Pua and Black Jasmine) and rice bran oil was produced. After 8 weeks of storage, the viability of the probiotics in terms of multistrains was 7.36 ± 0.04 log CFU g–1 (85.78% survival rate). Microbiological safety testing indicated that the amounts of contaminants were acceptable. This study provided the first scientific report on the feasibility of applying Thai-pigment rice, rice bran oil and mixed-culture probiotics as a novel functional synbiotic product. 相似文献
16.
Deyun Yuan Youn Young Shim Martin J.T. Reaney Venkatesh Meda 《International Journal of Food Science & Technology》2016,51(3):690-699
An ion‐pair reversed‐phase high‐performance liquid chromatography (HPLC) method was developed for the analysis of sinigrin in Ethiopian mustard (Brassica carinata A. Braun) seed and seed fractions. Separation was compared on several RP‐HPLC columns (Inertsil® ODS‐4 C18 and ZORBAX® Eclipse XDB‐C18) with an isocratic eluent containing 100% aqueous (aq.) tetramethylammonium bromide (10 mm , pH 5.0). Sinigrin retention was affected by HPLC variables including the type of ion‐pair reagent, buffer strength and pH, acetonitrile concentration, column temperature and eluent flow rate. Partial validation demonstrated this optimised chromatographic condition to be linear, accurate and precise. Multistage extraction using 70% (v/v) aq. methanol was more efficient than 50% (v/v) aq. acetonitrile. In addition, the matrix effect and recovery rate as well as processing efficiency of the analytical protocol were determined. This method is suitable for high throughput analysis of sinigrin in Ethiopian mustard seed and seed fractions. 相似文献
17.
We study the correlation of intensity fluctuations in random electromagnetic beams, the so-called Hanbury Brown–Twiss effect (HBT). We show that not just the state of coherence of the source, but also its state of polarization has a strong influence on the far-zone correlations. Different types of sources are found to have different upper bounds for the normalized HBT coefficient. 相似文献
18.
19.
Emer Shannon Nissreen Abu‐Ghannam 《International Journal of Food Science & Technology》2018,53(9):2195-2204
Brown seaweeds contain a number of bioactive compounds. The xanthophyll, fucoxanthin, has in vivo efficacy against disorders such as type 2 diabetes, obesity and cancer. Organic solvents are traditionally employed to extract fucoxanthin, but carry a toxic chemical and environmental burden. The aim of this study was to optimise a fucoxanthin extraction method using enzymes, water, low‐temperature dehydration and mechanical blending, to produce yields comparable to those achieved with an organic solvent (acetone). Response surface methodology was applied, using Fucus vesiculosus as a model species. A fucoxanthin yield of 0.657 mg g?1 (dry mass) was obtained from F. vesiculosus blade using the enzymatic method, equivalent to 94% of the acetone‐extracted yield. Optimum extraction parameters were determined to be enzyme‐to‐water ratio 0.52%, seaweed‐to‐water ratio 5.37% and enzyme incubation time 3.05 h. These findings may be applied to the development of value‐added nutraceutical products from seaweed. 相似文献
20.
Solmaz Tabtabaei David G. B. Boocock Levente L. Diosady 《Journal of the American Oil Chemists' Society》2014,91(7):1269-1282
The multi-stage treatment of stable oil-in-water emulsions produced during non-enzymatic aqueous processing of dehulled yellow mustard flour with cyclic ethers [tetrahydrofuran (THF) and 1,4-dioxane] was investigated to produce a single-phase oil-solvent-water miscella suitable for biodiesel production. While the single-stage treatment of yellow mustard emulsion recovered 97 % and 95 % of the oil by using 4:1 THF:oil and 9:1 dioxane:oil weight ratios, respectively, miscella phases containing more than 7 % water formed, which made them unsuitable as biodiesel feedstock. Multi-stage treatments of the emulsion using lower THF:oil and dioxane:oil weight ratios were further developed to produce oil-solvent-water miscella phases with low water content. While three-stage extraction of emulsions using 0.5:1, 1:1, 1.5:1, and 2:1 dioxane:oil weight ratios did not destabilize the emulsion, three-stage extraction using 0.5:1 and 0.75:1 THF:oil weight ratios effectively recovered over 97 % of the oil, resulting in the production of oil-rich miscella phases containing only 1 % and 1.5 % water, respectively. These miscella phases were analyzed for free fatty acid and phosphorus contents and proved to be excellent feedstocks for the preparation of high-purity methyl esters through single-phase base-catalyzed transmethylation. 相似文献