新型松香石蜡阳离子中性施胶剂的制备及应用

以N-甲基吡咯烷酮(NMP)为助溶剂,苯乙烯(St)、丙烯酸十八酯(ODA)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)、丙烯酰胺(AM)为单体,通过无皂乳液共聚反应合成了阳离子高分子乳化剂(CPE),并制备了阳离子松香石蜡乳液(CRPE).研究TCPF合成中St、ODA、DMC含量对CRPE稳定性能的影响;CRPE中松香、石蜡、CPE质量比对CRPE稳定性能以及施胶性能的影响;纸浆pH、CRPE用量及非离子聚丙烯酰胺用量对纸张施胶效果的影响.结果表明:W(St)=33%、w(ODA)=15%、w(DMC)=17%、m(松香):m(石蜡):m(CPE)=2:1:3时CRPE稳定性能较好,适宜的施胶条件为:采用逆向施胶工艺纸浆pH值为6,CRPE用量为1%,PAM用量为0.8%.     

无皂阳离子C-9石油树脂/石蜡育果袋纸表面施胶剂的制备及应用

以N甲基吡咯烷酮（NMP）为溶剂,通过自由基溶液聚合反应合成了阳离子高分子乳化剂,并制备了阳离子C-9石油树脂/石蜡乳液。研究了高分子乳化剂合成中亲水性单体DMC及溶剂NMP含量对乳液稳定性能的影响;乳液中C-9石油树脂、石蜡、高分子乳化剂质量比对乳液稳定性能以及施胶性能的影响;乳液施胶浓度对施胶效果的影响。结果表明：w（DMC）=25%、w（NMP）=43%、m（C-9石油树脂）：m（石蜡）：m（高分子乳化剂）=5：5：10时乳液稳定性能较好;当施胶浓度为2.3%,施胶后纸张综合性能好,其施胶度为129s,抗张强度为5.13kN/m,湿抗张强度1.72kN/m。     

阳离子松香/AKD中性施胶剂的制备及应用

以N甲-基吡咯烷酮（NMP）为助溶剂,丙烯酰胺（AM）、甲基丙烯酰氧乙基三甲基氯化铵（DMC）、丙烯酸十八酯（ODA）、苯乙烯（St）为单体,通过无皂乳液共聚反应合成了阳离子高分子乳化剂,并制备了阳离子松香/AKD乳液。研究了高分子乳化剂合成中AM、DMC用量对乳液稳定性的影响,乳液中松香、AKD、高分子乳化剂质量比对乳液稳定性及施胶性能的影响,以及纸浆pH值、乳液用量对施胶效果的影响。结果表明：AM用量为35%,DMC用量为15%,松香、AKD和高分子乳化剂的质量比为11∶4∶3时乳液稳定性较好。适宜的施胶条件为：采用逆向施胶工艺,松香、AKD和高分子乳化剂的质量比为11∶4∶3,纸浆pH值为6,乳液用量为1%。     

反应型阳离子高分子乳化剂合成及其对AKD/松香乳化性能的研究

以N-甲基吡咯烷酮(NMP)作为助溶剂,偶氮二异丁腈(AIBN)作为引发剂,丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)、丙烯酸十八酯(ODA)、苯乙烯(St)作为单体,通过无皂乳液聚合合成了阳离子高分子乳化剂(共聚物乳液),并制备了阳离子AKD/松香胶(施胶剂乳液)。考察了反应温度对单体转化率的影响及用不同w(AM)、w(DMC)、w(St)合成的共聚物乳液制备的施胶剂乳液离心稳定性能。结果表明:在共聚物乳液合成过程中,m(AM):m(DMC):m(St):m(ODA)=35:15:25:25时用其制备的施胶剂乳液具有较好的稳定性能;反应温度为70℃时单体转化率高,为95%。用最大气泡法测共聚物乳液的表面张力,得其临界胶束浓度为0.42×10-7mol/L。最后采用FT-IR对共聚物乳液进行了表征,纸张抄片结果表明施胶剂具有较好的防水性能。     

阳离子无皂松香/石蜡乳液的制备及其施胶性能

通过无皂乳液聚合法制得阳离子聚丙烯酸酯高分子乳化剂,并以此制备系列阳离子无皂松香/石蜡乳液。研究了高分子乳化剂制备的主要影响因素,并通过与传统的阳离子松香乳液的对比应用实验,分析了阳离子无皂松香/石蜡乳液与传统阳离子松香乳液的差别。结果表明,当w(丙烯酰胺)=25%,w(甲基丙烯酰氧乙基三甲基氯化铵)=20%,w(聚丙烯酸酯乳化剂)=15%时,乳液趋于稳定,并具有良好的施胶和增强效果;与传统的阳离子松香乳液相比,阳离子无皂松香/石蜡乳液在较高pH值下仍具有较好的施胶效果,且在相同用量下,阳离子无皂松香/石蜡乳液具有更好的施胶效果。     

ASA高分子乳化剂的制备及应用

以聚乙烯醇(PVA)为分散剂,苯乙烯(st)、丙烯酸丁酯(BA),甲基丙烯酰氧乙基三甲基氯化铵(DMC)和丙烯酰胺(AM)为主要单体,通过无皂乳液聚合制备了新型高分子乳化剂.用该高分子乳化剂制成ASA乳液,并对AsA乳液的稳定性和应用效果进行了研究.结果表明:当高分子乳化剂与AsA的质量比为1.5∶1时,ASA乳化效果较好;在浆内施胶过程中,当AsA乳液用量为0.8%,硫酸铝用量为1.5%,CaCO3填料用量不超过15%时较为适宜,最大施胶度可达到101s.     

阳离子活性聚合物/AKD乳液的施胶和增强作用

以合成的阳离子活性聚合物作为高分子乳化剂,制备了阳离子活性聚合物/AKD乳液。研究了乳液制备过程的主要影响因素,并比较了阳离子活性聚合物/AKD乳液与传统AKD乳液对纸张的增强性能。结果表明,当m(阳离子活性聚合物)∶m(AKD)=0.30时可制得稳定乳液,乳液具有很好的施胶和增强效果,且明显优于传统的AKD乳液。当乳液(固含量为15%)以用量0.13%(对w=5%的淀粉溶液)进行施胶时,纸张施胶度可以达到40s,环压指数提高了13.6%,耐折度提高了185%。纸张表面的SEM分析显示,经阳离子活性聚合物/AKD乳液施胶后的纸张表面,纤维间的界面变的模糊,纤维结合更加紧密。     

含氟丙烯酸酯乳液的制备及其用作纸张防油剂的研究

以甲基丙烯酸十二氟庚酯(FM),丙烯酸丁酯(BA)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)、N-羟甲基丙烯酰胺(NMA)为原料.制备了自乳化阳离子含氟丙烯酸酯多元共聚物乳液.将w(DMC)=10%、软硬单体比例n(BA)/n(FM)=1.1、w(NMA)=5%时所合成的乳液以质量分数5%进行表面施胶,施胶量为1.2 g/m2时,抗油渗透时间为62 min,表面强度达4.3 m/s.并通过红外光谱(FT-IR)、差示扫描量热(DSC)和透射电镜(TEM)等埘乳液性能和共聚物结构进行了表征.结果表明,共聚物玻璃化转变温度为50%左右,乳液粒子呈规则球形,乳胶粒平均粒径为96～102 nm.     

阳离子石蜡/ASA乳液的制备与应用

考察了乳化温度、乳化剂的用量和乳化剂的组成等因素对石蜡/烯基琥珀酸酐(ASA)乳液性质的影响,确定了石蜡/ASA乳液的最佳制备条件,制得乳液的平均粒径为0.196μm。石蜡/ASA乳液与阳离子松香共混后施胶的结果表明,石蜡/ASA乳液具有较好贮存稳定性和对阳离子松香乳液的施胶增效作用。     

乙二醛改性淀粉基苯乙烯丙烯酸酯乳液的制备及其表面施胶性能

利用低黏度阳离子淀粉(CS-8)的乳化、分散作用,采用无皂乳液聚合的方法,以苯乙烯(St)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)和甲基丙烯酸二甲基氨基乙酯(DM)为主要原料,合成核壳型阳离子苯乙烯丙烯酸酯乳液(SAE),并引入乙二醛对淀粉基SAE进行改性。讨论了制备条件对乳液性能和施胶性能的影响,并对乙二醛改性SAE与未经乙二醛改性SAE、商品苯丙乳液8906的表面施胶性能进行了比较。实验结果表明:当w(CS-8)=8%,m(St)/m(BA)=9:11,w(乙二醛)=10%时,所制SAE乳液性能优异,施胶效果良好。添加乙二醛对淀粉基SAE进行改性提高了乳液对纸张憎水性能和物理强度的改善作用,其施胶效果优于商品苯丙8906。     

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