微波辐射下纸张增干强剂P（AM-DMC）的制备

对微波辐射下丙烯酰胺（AM）和甲基丙烯酰氧乙基三甲基氯化铵（DMC）的水溶液聚合反应进行了研究,制备了P（AM-DMC）阳离子聚丙烯酰胺纸张增干强剂。探讨了引发剂用量、单体配比、微波功率、反应时间等对聚合物相对分子质量和纸张增干强作用的影响,确定了最佳合成工艺,并用红外光谱对产物的结构进行了表征。结果表明：当微波辐射功率为528W,引发剂用量为0.35g,单体配比AM：DMC为12：3.75,辐射时间为4min时聚合物对纸张的增干强性能最好。     

反相微乳液聚合制备新型阳离子聚丙烯酰胺絮凝剂

以丙烯酰胺（AM）和丙烯酰氧乙基三甲基氯化铵（DAC）为共聚单体,采用反相乳液微聚合法合成了稳定的聚丙烯酰胺微乳液。探讨了乳化剂、油水质量比、单体浓度、引发剂用量和阳离子度等因素对产物相对分子质量的影响,确定了最佳合成条件,并将其与国内外产品进行了絮凝效果对比。     

阳离子胶原蛋白絮凝剂的制备及表征(续)

以皮革废弃物提取的明胶为原料,丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为单体(AM∶DAC摩尔比为4∶1),叔丁基过氧化氢和焦亚硫酸钠为引发剂,接枝共聚合成了阳离子胶原蛋白絮凝剂P(C-AM-DAC)。以絮凝剂对油田模拟废水的浊度去除率为指标,通过响应面法优化了P(C-AM-DAC)接枝共聚条件:m(明胶)∶m(单体)为1∶1.92、引发剂用量0.03mol/L、接枝温度44.2℃、接枝时间3.0h。在此条件下制备的新型絮凝剂表现出优异的絮凝效果,对油田模拟废水中污染物去除率可达91.3%。同时利用傅立叶变换红外光谱(FT-IR)和热重分析(TGA)对其进行表征。     

阳离子胶原蛋白絮凝剂的制备及表征(续)

以皮革废弃物提取的明胶为原料,丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为单体(AM∶DAC摩尔比为4∶1),叔丁基过氧化氢和焦亚硫酸钠为引发剂,接枝共聚合成了阳离子胶原蛋白絮凝剂P(C-AM-DAC)。以絮凝剂对油田模拟废水的浊度去除率为指标,通过响应面法优化了P(C-AM-DAC)接枝共聚条件:m(明胶)∶m(单体)为1∶1.92、引发剂用量0.03mol/L、接枝温度44.2℃、接枝时间3.0h。在此条件下制备的新型絮凝剂表现出优异的絮凝效果,对油田模拟废水中污染物去除率可达91.3%。同时利用傅立叶变换红外光谱(FT-IR)和热重分析(TGA)对其进行表征。     

阳离子胶原蛋白絮凝剂的制备及表征

以皮革废弃物提取的明胶为原料,丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为单体(AM∶DAC摩尔比为4∶1),叔丁基过氧化氢和焦亚硫酸钠为引发剂,接枝共聚合成了阳离子胶原蛋白絮凝剂P(C-AM-DAC)。以絮凝剂对油田模拟废水的浊度去除率为指标,通过响应面法优化了P(C-AM-DAC)接枝共聚条件:m(明胶)∶m(单体)为1∶1.92、引发剂用量0.03mol/L、接枝温度44.2℃、接枝时间3.0h。在此条件下制备的新型絮凝剂表现出优异的絮凝效果,对油田模拟废水中污染物去除率可达91.3%。同时利用傅立叶变换红外光谱(FT-IR)和热重分析(TGA)对其进行表征。     

P（AM-DMDAAC-AA）两性聚电解质的合成及其对白水中Ca2+吸附性能的研究

以丙烯酰胺(AM)为分子骨架,丙烯酸(AA)和二甲基二烯丙基氯化铵(DMDAAC)分别为阴、阳离子单体,采用过硫酸钾(KPS)与偶氮二异丁脒盐酸盐(AIBA·2HCl)组成的复合引发体系,在水相中共聚合成了一种具有两性特征的水溶性高聚物P(AM-DMDAAC-AA).通过考察单体质量分数、引发剂用量、单体配比等因素对产物特性黏数和Ca2吸附性能的影响,确定了反应的最佳合成条件:单体摩尔比n(AM)∶n(DMDAAC)∶n(AA)=1∶0.3∶0.8,单体质量分数22.5％(单体总质量对反应体系总质量),引发剂用量0.2％(相对于单体总质量),其中KPS与AIBA·2HCl的质量比为3∶1,反应温度70 ～ 75℃,反应时间10h.合成的聚合物特性黏数为231.48 mL/g,Ca2吸附量最高能达到2.028 mmol/g.运用FT-IR和1H-NMR对聚合物结构进行了表征.     

AKD专用新型阳离子聚合物乳化剂的制备与应用

以阳离子聚合物为分散剂,丙烯酰胺（AM）、二烯丙基二甲基氯化铵（DMDAAC）为单体,过硫酸铵为引发剂,制备了一种AKD专用新型阳离子聚合物乳化剂,并用此乳化剂乳化AKD蜡,制得阳离子AKD乳液。考察了单体配比,反应温度,反应时间对聚合物乳化性能的影响。结果表明：阳离子分散剂用量20%,AM用量9%,DMDAAC用量1%,反应温度80℃,反应时间2 h,制得的聚合物对AKD具有较好的乳化性能。利用该乳化剂进行中试生产,产品粒径0.98μm,纸厂实际应用效果良好。     

AKD专用新型阳离子聚合物乳化剂的制备与应用

以阳离子聚合物为分散剂,丙烯酰胺（AM）、二烯丙基二甲基氯化铵（DMDAAC）为单体,过硫酸铵为引发剂,制备了一种AKD专用新型阳离子聚合物乳化剂,并用此乳化剂乳化AKD蜡,制得阳离子AKD乳液。考察了单体配比,反应温度,反应时间对聚合物乳化性能的影响,结果表明：阳离子分散剂用量20%,AM用量9%,DMDAAC用量1%,反应温度80℃,反应时间2h,制得的聚合物对AKD具有较好的乳化性能。利用该乳化剂进行中试生产,产品粒径0.98μm,纸厂实际应用效果良好。     

分散聚合法制阳离子聚丙烯酰胺及其对竹浆废水的絮凝性能

以丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为共聚单体,采用分散聚合法在无机盐水溶液中得到了性能稳定的聚合物乳液。产物的红外光谱及粒径分析表明,这种分散聚合法在制备阳离子聚丙烯酰胺乳液上是成功的。将所得阳离子聚丙烯酰胺乳液(CPAM)与聚硅氯化铝配合使用处理竹浆废水,结果表明自制阳离子聚丙烯酰胺具有良好的絮凝性能。     

过硫酸铵引发阳离子淀粉接枝共聚物合成与表征

采用水溶液聚合方法,以过硫酸铵(APS)为引发剂,将玉米淀粉(St)与丙烯酰氧乙基三甲基氯化铵(DAC)单体接枝聚合,制备阳离子淀粉高分子聚合物。讨论单体质量比、引发剂用量、反应温度和反应时间等因素对聚合物阳离子度的影响。结果表明：当加入淀粉质量1.0%的过硫酸铵,DAC与淀粉质量比2.5:1,50℃反应8h时,接枝共聚物的阳离子度最高可达53.68%。用红外光谱、扫描电镜、热失重分析对接枝共聚物结构进行表征,表征结果均证实阳离子淀粉高分子聚合物制备成功。     

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.     

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.