改性淀粉絮凝剂的制备及其在造纸废水处理中的应用

以玉米淀粉和丙烯酰胺为原料、硝酸铈铵为引发剂,通过接枝共聚反应对淀粉进行改性,合成了淀粉/丙烯酰胺接枝共聚物(SAM),即改性淀粉絮凝剂。将合成的SAM絮凝剂用于造纸废水絮凝处理,讨论了SAM絮凝剂用量、废水的温度和p H值等因素对处理效果的影响。研究显示,在丙烯酰胺与淀粉质量比为2∶1、引发剂浓度2.0 mmol/L、反应温度40℃、反应时间3 h、反应体系p H值4.0的条件下,SAM絮凝剂合成反应的接枝率达到68.5%;红外光谱分析表明丙烯酰胺成功接枝在玉米淀粉基质中。将SAM絮凝剂用于处理混合造纸废水,当SAM絮凝剂用量为12 mg/L、废水p H值7~9、温度30℃条件下,CODCr去除率为88.4%,浊度去除率为91.2%,BOD5去除率为85.5%,处理后废水透光率为93.3%。     

淀粉接枝聚丙烯酰胺用于漂白废水处理

研究了淀粉接枝聚丙烯酰胺作为絮凝剂对漂白废水进行处理,通过实验比较了淀粉接枝聚丙烯酰胺絮凝剂与其他絮凝剂对漂白废水的絮凝效果,确定了淀粉接枝聚丙烯酰胺絮凝剂和明矾[Al2（SO4）3]配合使用的合适比例。结果表明：不同絮凝剂对漂白废水的絮凝效果好坏依次是Al2（SO4）3/St-PAM、St-PAM、PAM、Al2（S04）3。采用Al2（SO4）3和St-PAM混合使用时,Al2（SO4）3和St-PAM的最佳配比为1：1。     

阳离子淀粉改性絮凝剂的制备及其对油脂废水的絮凝效果

研究了阳离子淀粉与丙烯酰胺接枝共聚反应制备阳离子型絮凝剂的工艺,并以油脂废水为实验对象对絮凝剂的絮凝性能进行了考察。其最佳制备条件：丙烯酰胺与阳离子淀粉的质量比为3：1,高锰酸钾引发剂加入量为丙烯酰胺质量的0．15％,pH2～3,反应温度50qC,反应时间3h。絮凝效果实验中,接枝共聚物絮凝剂的最佳加入量为8mg／L,COD去除率达到45％以上。     

蒸汽爆破对蔗渣比表面积及接枝丙烯酰胺的影响

以蔗渣比表面积为指标,通过单因素实验考查了蒸汽爆破预处理条件如蒸爆压力、保压时间、蔗渣含水率对爆破后蔗渣比表面积的影响。并以蒸爆后的蔗渣为原料,通过接枝共聚合反应制备蔗渣接枝丙烯酰胺,探讨比表面积对蔗渣接枝聚丙烯酰胺接枝率的影响。结果表明,比表面积的增加有助于提高蔗渣接枝丙烯酰胺的接枝率,最佳蒸爆预处理条件为:蒸爆压力2.0 MPa,保压时间60 s,蔗渣含水率25%。     

蔗渣浆中段废水混凝沉淀-活性污泥生化处理的工艺研究

通过试验 ,研究聚丙烯酰胺、聚合氯化铁、聚合氯化铝三种絮凝剂对蔗渣浆中段废水的絮凝处理效果。并对以化学混凝沉淀作为前期处理 ,再结合活性污泥法处理蔗渣浆中段废水的可生化性与处理效果进行研究     

淀粉接枝聚丙烯酰胺用于造纸废水处理

本文采用实验室研制的颗粒淀粉与丙烯酰胺接枝共聚产物作絮凝剂对废纸脱墨废水进行处理，获得良好的效果。通过实验探讨了淀粉接枝聚丙烯酰胺的加入量、废水的PH及絮凝时间对絮凝效果的影响，确定了淀粉接枝聚丙烯酰处理废纸脱墨废水的最佳条件。     

SAH阴离子天然高分子改性絮凝剂的合成及应用

本文研究了以玉米淀粉为基材,与丙烯腈(聚丙烯酰胺的降解回收料)进行接枝共聚,经水解制得弱阴离子型絮凝剂,并进一步羟甲基化和磺化,从而合成强阴离子型天然高分子改性絮凝剂-SAH.在探讨接枝共聚反应机理的基础上,重点阐明了引发剂浓度、原料投料比、反应温度、反应时间等对接枝率和接枝效率的影响.把SAH应用于印染废水及造纸厂污水的处理、COD去除率和浊度去除率都达到90%以上,取得了良好的絮凝效果.     

阳离子瓜尔胶改性絮凝剂的絮凝性能研究

以硝酸铈铵(CAN)为引发剂,采用水溶液聚合法,制备了阳离子瓜尔胶与丙烯酰胺的接枝共聚物(pAAm-g-CG40)。将制得的接枝共聚物作为阳离子絮凝剂,应用于生活污水的净化处理。结果表明,pAAm-g-CG40具有良好的絮凝效果,其絮凝作用优于阴离子聚丙烯酰胺(APAM)。而且,在与聚合铁(PFS)复合作用时,可大大提高其絮凝作用,更加有效地去除污水的浊度。     

SAH阴离子天然高分子改性絮凝剂的合成及应用

本文研究了以玉米淀粉为基材，与丙烯腈(聚丙烯酰胺的降解回收料)进行接枝共聚，经水解制得弱图离子型絮凝剂，并进一步羟甲基化和磺化，从而合成强阴离子型天然高分子改性絮凝剂-SAH．在探讨接枝共聚反应机理的基础上，重点阐明了引发剂浓度、原料投料比、反应温度、反应时间等对接枝率和接枝效率的影响，把SAH应用于印染废水及造纸厂污水的处理、COD去除率和浊度去除率都达到90％以上，取得了良好的絮凝效果。     

改性笋壳吸附剂的制备及其吸附性能研究

以竹笋加工业副产品笋壳为原料,经过碱预处理后,通过化学氧化法接枝丙烯酰胺单体制备笋壳接枝丙烯酰胺(BS-AM)吸附剂,对接枝反应条件如催化剂用量、接枝温度、单体浓度和浴比等进行优化,并通过红外、扫描电镜和能谱分析对笋壳接枝丙烯酰胺结构进行了表征,通过对汞离子的吸附考查改性笋壳的吸附性能。结果表明,丙烯酰胺被成功接枝到笋壳表面,在最优接枝条件下接枝率达到120%左右;能谱分析显示表面N含量高达11.9%;对汞离子的吸附容量达到420.8mg/g;在含重金属离子废水处理领域具有较好的工业应用前景。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

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.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press