乳液型改性淀粉增干强剂的制备及应用

可溶性淀粉溶解后,加入丙烯酸甲酯、苯乙烯、丙烯酰胺及二甲基二烯丙基氯化铵进行接枝共聚,即可得到乳液型改性淀粉增干强剂。该增干强剂对增加纸张干强度和耐撕裂度有明显效果,用量0.6％～1.0％（绝对干浆）时,可使纸的干强度增加20％以上,耐撕裂度提高3％以上,pH6.5～7.0,粘度10～20 mPa·s,ζ电位5～10mV.     

PSA型改性淀粉增干强剂的制备及应用

可溶性淀粉溶解后，加入丙烯酸甲酯，苯乙烯、丙烯酰胺及二甲基二烯丙基氯化铵进行接枝共聚，即可得到乳液型改性淀粉增干强剂，该增干强剂对增加纸张干强度和耐撕裂度有明显效果，用量0．6％－1．0％（）对绝干浆）时可使纸的干强度增加20％以上，耐撕裂度提高3％以上，pH6.5-7.0，粘度10－20mPa.s,ζ电位5－10mV。     

PVA-BA-MTA三元共聚物乳液增干强剂的研究

通过采用聚乙烯醇（PVA）、丙烯酸丁酯（BA）、甲基丙烯酰氧乙基三甲基氯化铵（MTA）为原料，采用无乳化剂乳液聚合法，制备出了一种阳离子共聚物乳液。测定了此乳液的转化率并考察了稳定性；同时发现当单体配比m（BA）：m（MTA）85：15时，引发剂（NH4）2S2O8为单体量的0.3％制得共聚物，其用量为1．2％（对绝干浆）时。可使纸张的环压指数提高29．86％，抗张指教提高30．92％。     

PAE-苯乙烯接枝共聚物乳液的稳定性及增强效果探讨

以PAE、苯乙烯为主要原料,在过硫酸铵-亚硫酸氢钠氧化还原引发体系下合成PAE-苯乙烯接枝共聚物乳液,并讨论了合成条件对乳液稳定性的影响及产物在造纸中的应用。作为瓦楞原纸增强剂时,添加1．0％（对绝干浆）的乳液,纸张的环压指数、挺度、抗张指数、耐破指数和耐折度可分别比空白样提高19．75％、27．02％、30．72％、32．06％和80％。最后通过扫描电镜分析了加入乳液前后纸页中纤维的交织情况,结果显示加入该聚合物乳液的成形纸页中的纤维结合更加紧密,说明其增强效果明显。     

新型聚丙烯酰胺乳液增强剂的合成及应用

采取乳液聚合法合成了水包水型PAM乳液增强剂,研究了反应条件如反应单体配比、反应时间、引发剂用量等对PAM乳液性能及对草浆成纸增强效果的影响,并与国内常用的增强剂进行了比较.     

羟丙酯改性阳离子醚化聚乙烯醇增干强剂的合成

以甲基丙烯酸羟丙酯(HPMA)为功能单体,甲基丙烯酰氧乙基三甲基氯化铵(DMC)为阳离子功能单体,2,3—环氧丙基三甲基氯化铵(GTMAC)为阳离子醚化剂,无皂乳液聚合法合成乳液增干强剂。通过FTIR及TEM对聚合物的结构及乳液粒子形态进行表征,探讨阳离子醚化剂的添加对乳液颗粒粒径的影响;去离子水的用量对乳液黏度的影响;引发剂的种类和用量对单体转化率的影响;及乳液添加量对纸张各项物理性能的影响。结果表明,加入阳离子醚化剂可使乳液粒径显著减小;水的质量分数为83.5%～84%时乳液的黏度较适宜;引发剂的用量达到0.3%,单体转化率最高;乳液添加量为1.2%,干抗张强度明显提高,其增加幅度为17.3%。     

聚丙烯酰胺在牛皮纸生产中的干增强效果

在牛皮纸生产中,用聚丙烯酰胺千强剂来替代两性淀粉提高纸张的干强度,对比了几种聚丙烯酰胺类增强剂的使用效果,并选用阳离子聚丙烯酰胺增强剂LX进行了中试试验.通过试验发现,在保证成纸原有干强度的前提下,增强剂LX用量为5 kg/t（纸）时,可替代两性淀粉8 kg/t（纸）,同时阳离子松香胶用量降低了2 kg/t（纸）,硫酸铝用量降低了22 kg/t（纸）,吨纸成本比现有工艺降低38元.     

水包水阳离子聚丙烯酰胺乳液合成条件的研究

该文采用自制的分散体系,通过乳液聚合法合成了系列水包水阳离子聚丙烯酰胺乳液,对影响聚合反应和乳液稳定性及使用效果的主要条件如电解质加入量、引发剂加入前后丙烯酰胺单体加入配比、分散剂及螯合剂等进行了讨论,得出了合成阳离子聚丙烯酰胺乳液的最佳合成方式及各种试剂的最佳加入量.     

阳离子无皂乳液的制备及其在涂料染色中的应用

选择合适的阳离子单体和引发剂,采用无皂乳液聚合的方法,合成了稳定的阳离子型聚合物乳液.分析了单体(软单体丙烯酸丁酯BA、硬单体苯乙烯St、阳离子单体DMC)、引发剂过硫酸铵APS用量和搅拌速度等因素对乳液粒径及稳定性的影响.结果表明:当单体DMC、BA、St用量分别为13.14%(对体系质量)、6.18%(对体系质量)和2.32%(对体系质量),引发剂用量0.5%(对单体质量),搅拌速度250 r/min时,合成的阳离子乳液粒径为383.3 nm,具有较好的稳定性.应用于涂料染色织物,经过改进的阳离子聚合物乳液具有比商品粘合剂高的干摩擦牢度和较好的湿摩擦牢度.电子显微镜(SEM)和原子力显微镜(AFM)的观察结果说明,阳离子乳液能够在织物表面形成更完整均匀的聚合物薄膜.     

改性苯乙烯-丙烯酸酯胶乳表面施胶剂的合成及研究

以甲基丙烯酸十二氟庚酯（FM）、丙烯酸丁酯（BA）、苯乙烯（St）、甲基丙烯酰氧乙基三甲基氯化铵（DMC）、丙烯酸十八酯（ODA）为原料,采用无皂孔液聚合制得了阳离子含氟丙烯酸酯改性的苯乙烯-丙烯酸酯（SAE）乳液。对聚合物的结构、组成进行了表征,并研究了引发剂、FM的用量对乳液耐水性和稳定性的影响。单独使用含氟乳液对纸张进行表面施胶,水和油滴在纸张上所成的接触角最大可分别达到121°和80°,同时纸张的抗张强度、耐折度,白度、平滑度分别提高11．36％、7．14％、0．25％、50．48％。由于使用的阳离子化试剂是季铵盐型,所以可适用广泛pH值范围,可同时应用于酸性施胶、碱性施胶和中性施胶。     

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