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1.
研究了负载型纳米光触媒处理染料废水.结果表明:用活性炭作载体,煅烧温度350℃的光触媒处理效果较好,能有效降解染料废水(降解效果比氧化铝负载型光触媒好),无二次污染,同时解决了分离回收和重复使用的难题.活性炭负载型光触媒[w(纳米TiO2)=8.6%(对活性炭负载型光触媒质量)]用量20 g/L,光催化染液(50 mg/L)30 min,脱色率可达86%左右.  相似文献   

2.
利用壳聚糖的澄清性能和活性炭的多孔吸附性能,通过浸渍法制备了活性炭负载壳聚糖吸附剂,用扫描电镜和X射线衍射仪对此吸附剂进行形貌和晶相表征,并进行了糖汁吸附脱色实验研究。结果表明,相比单一的活性炭,其脱色率提高了10.1%。当此吸附剂用量为0.4%(质量分数),吸附p H为6.0、吸附温度为80℃、吸附时间为60 min时,对糖汁的脱色率与0.5%(质量分数)活性炭的脱色率基本一致,说明活性炭负载壳聚糖更有利于对糖汁清净脱色。  相似文献   

3.
以狗毛作为催化剂载体,采用浸渍法负载Fe3+,制备了非均相Fenton反应催化剂,并将其用于催化活性蓝M-B模拟废染液的脱色.结果表明:在初始染料质量浓度为100 mg/L的50 mL模拟废染液中,添加Fe3+吸附量为33.0 mg/g的狗毛非均相Fenton反应催化剂0.4 g以及30%的H2O20.4 mL/L,脱色液pH控制在6左右,室温(25℃)下,脱色反应120 min,活性蓝M-B脱色率可达85%.  相似文献   

4.
采用离子交换法和浸渍法制备Al-Zr-CeO2固体酸催化剂,利用SEM、XPS、XRD、FT-IR和氮气吸附—脱附对固体酸催化剂进行了表征,结果表明:Al2O3和ZrO2负载在CeO2表面,大大提升了Al-Zr-CeO2复合催化剂的比表面性能,在高温下仍有较高的比表面积,且催化效果显著。同时以大豆油的环氧化反应为探针反应,考察了煅烧温度、煅烧时间、Al(NO3)3/CeO2的质量比和 Zr(NO3)4/CeO2的质量比对催化剂Al-Zr-CeO2催化活性的影响。催化剂的最佳制备条件为:煅烧温度为400℃,煅烧时间为2h,Al(NO3)3/CeO2的质量比为0.2,Zr(NO3)4/CeO2的质量比为0.2。该条件下制备的催化剂催化大豆油的环氧化反应时,环氧值可达到5.54%。  相似文献   

5.
为研究国内外活性炭在玉米朊脱色过程中吸附色素特性的差异,以玉米朊的乙醇萃取溶液和商业玉米朊 产品乙醇复溶溶液为研究对象,分别采用国产活性炭(ACP)和进口活性炭(ACD)对比研究其对玉米朊的脱色效 果,并对活性炭的微观结构进行表征。静态吸附实验结果表明,活性炭对玉米朊复溶溶液和萃取液的脱色效果没有 明显差异;ACP对玉米朊溶液中色素的吸附率(77.31%)略高于ACD(67.27%)。扫描电子显微镜分析表明,ACP 结构向内延伸而ACD表面凹陷孔结构不明显;比表面积和孔隙结构分析表明,ACP的比表面积(1 438.082 m2/g) 和总孔容积(1.310 cm3/g)大于ACD(779.809 m2/g、0.626 cm3/g),且ACP具有更多的微孔和中孔结构。ACD表 面含有较多的羧酸和内酯类官能团,可与色素分子中的羟基结合,从而有效增强活性炭的化学吸附效果。ACD粒 径分布更加集中,有利于脱色后的固-液分离。综合以上因素考虑,ACD更适合用于黄色玉米朊的脱色处理。  相似文献   

6.
黄粉虫幼虫降血压肽酶解液脱色工艺的优化   总被引:3,自引:0,他引:3  
采用粉末活性炭对脱脂黄粉虫幼虫降血压肽酶解液进行脱色处理.通过单因素和正交实验,考察了活性炭用量、pH、温度和吸附时间等因素对脱色率(DE)、肽损失率(LP)和溶液对血管紧张素酶(ACE)的活性抑制率(IP)的影响.结果表明,粉末活性炭用量3%,pH3,脱色温度40℃,吸附时间50min的条件下,黄粉虫幼虫降血压肽酶解液脱色效果明显,脱色率为85.3%,ACE抑制活性为70.8%.  相似文献   

7.
利用活性炭对猪血粉酶解液进行脱色,研究了活性炭用量、pH值、脱色温度和吸附时间对猪血粉酶解液脱色效果的影响。试验结果表明:活性炭对猪血粉酶解液具有理想的脱色效果,最佳脱色工艺参数为活性炭用量2.5%,pH 4.0,脱色温度60℃,吸附时间1.0h,在此最佳脱色工艺条件下脱色率达92.20%,同时氮损失率为10.42%。  相似文献   

8.
染料废水的臭氧/纳米氧化铁催化氧化脱色   总被引:1,自引:0,他引:1  
采用臭氧/纳米氧化铁催化氧化技术对活性染料废水进行脱色处理.以硅藻土为载体,采用浸渍-沉淀方法负载水合铁氧化物,以110℃烘干和290℃焙烧样品制备催化剂,并与硅藻土原土及双氧水进行臭氧催化氧化对比试验.结果表明,硅藻土负载纳米铁氧化物对臭氧氧化染料废水具有良好的催化性能,其催化效果比双氧水好;其中又以烘干样品的性能优于焙烧样品,经过6 min氧化,色度去除率可达95%以上;天然硅藻土的催化性能较差,总体脱色效果较单独臭氧氧化效果差.  相似文献   

9.
采用单因素和正交实验法,用粉末活性炭对含蛋黄降压肽的酶解液进行脱色处理,考察了活性炭用量、pH、脱色温度和吸附时间等因素对脱色率、肽损失率和溶液活性损失率的影响。结果表明,粉末活性炭用量3%,pH4.5,脱色温度40℃,吸附时间30min的条件下,蛋黄降压肽酶解液脱色效果明显,肽损失率(LP)可控制在20%以下,脱色率(DE)可达到86.3%,而酶解液对血管紧张素酶(ACE)的抑制率(IP)为77.89%,活性损失率为6.39%。  相似文献   

10.
刘丹丹  王中来  胡雅娜  魏璇 《食品工业科技》2012,33(18):253-256,260
以活性炭为载体,采用溶胶-凝胶法固定TiO2光催化剂,研究了焙烧时间、焙烧温度和浸渍比(即活化剂与活性炭的质量比)三个因素对固定化效果的影响。在单因素实验的基础上,运用二次回归正交旋转组合设计对TiO2光催化剂在活性炭上的固定化条件进行优化,并建立回归模型方程,确定光催化剂的最佳固定化条件。自行研制冷电弧-光催化-吸附集成反应器,其内装填固定化后的光催化剂。用该反应器对枸杞多糖进行脱色,以枸杞多糖的脱色率和多糖保留率为指标,考察固定化效果。实验结果表明,最佳固定化条件为焙烧时间1.90h、焙烧温度510℃和浸渍比2.82:1,此条件下得到的固定化光催化剂,装填在集成反应器中对枸杞多糖进行脱色,脱色率为80.9%,多糖保留率为80.4%。  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

13.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

14.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

15.
16.
The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.  相似文献   

17.
18.
This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.  相似文献   

19.
The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.  相似文献   

20.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

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