新闻纸生产用脱墨浆的还原性漂白

分别采用连二亚硫酸钠(Y)、甲脒亚磺酸(FAS)对新闻纸生产用脱墨浆进行了还原漂白的研究,两种还原漂白剂均可获得较高的白度增值和较低的黄度,漂后浆的物理强度较未漂浆有不同程度的改善,而且成本也较过氧化氢低,还原漂白剂代替过氧化氢来进行废报纸脱墨浆的后段漂白是可行的.     

木聚糖酶处理对亚硫酸镁浆酸性过氧化氢漂白机理的研究

采用X-射线衍射法和傅立叶变换红外光谱法进行木聚糖酶(X)对亚硫酸镁法竹子/蔗渣浆酸性过氧化氢(POs)漂白影响机理的研究.两种方法均能很好地反映镁盐浆纤维素的结晶结构在POs漂及X-POs漂前后的变化.所研究的几种浆样的纤维素均呈纤维素I晶态:(002)面峰较尖削,(101)面峰与(101)面峰重迭且呈圆钝形;常规POs漂浆和x-POs漂浆均比未漂浆的结晶度低,但x-POs漂浆比常规POs漂浆结晶度高.结果表明,经木聚糖酶处理的POs漂比常规POs漂既能有效地降解浆中的残留木素,又能更好地保护碳水化合物.     

麦草烧碱-AQ法浆较佳漂序的选择

本文比较了相同初始卡伯值时烧碱-AQ麦草浆CEH、DQP和D(EOP)D漂白浆与桉木的DQP漂白浆的白度,研究了漂后麦草浆的黏度、打浆性能、纸页的物理强度及废水的污染负荷.结果表明,相同卡伯值时,麦草浆CEH和D(EOP)D漂白浆白度低于DQP漂白浆白度,然而,均为DQP漂白,麦草浆白度低于桉木浆的白度.麦草浆DQP漂白浆表面木素含量也低于CEH漂白浆.麦草浆不同漂序所得浆料黏度的比较表明,相同卡伯值时,CEH漂白浆黏度远低于DQP和D(EOP)D漂白浆的黏度.后续打浆性能、纸页的物理强度及废水的污染负荷的检测结果也表明,DQP和D(EOP)D漂序显著优于CEH.而DQP漂序又优于D(EOP)D漂序,因此,DQP漂序是漂白麦草烧碱-AQ浆的最佳选择.     

漆酶-介体系统处理麦草化学浆全无氯漂白性能的研究

采用漂酶-介体系统对麦草化学浆进行预处理．研究了几种全无氯漂白(TCF漂白)[氧碱脱木质素配合两段过氧化氢漂白(OEPP)、两段过氧化氢漂白(QPP)和过乙酸配合一段过氧化氢漂白(PaP)]对漆酶处理后纸浆漂白性能的作用。结果表明：麦草浆经过漆酶预处理后．白度上升了12．9个白度单位(％．ISO)，漆酶处理浆氧碱脱木质素配合过氧化氢漂白后比原浆在相同条件下漂白后白度高14个白度单位以上．经两段过氧化氢漂白后白度比原浆在相同条件下(过氧化氢用量4％)漂白后白度高18．3个白度单位．经过乙酸过氧化氢漂白后比原浆在相同条件下漂白后白度高8．1个白度单位。漆酶处理浆漂白后强度比原浆漂白后低。但是其白度高．如漂至相同的白度可以节约大量漂剂，有利于改善浆的质量．降低漂白废水的污染负荷。     

棉秆亚钠化机浆汽相蒸煮及可漂性的研究

本研究旨在使用棉秆原料生产得率较高、强度性能较好的可漂浆。实验表明：采用回用浸渍液的汽相蒸煮，盘磨解离的工艺，在所选定的实验条件下，可得得率７４％的性能良好的纸浆，并可回用原预浸液中６０％的ＳＯ＿２。漂白采用次氯酸盐和过氧化氢两段漂或过氧化氢单段漂，均可将此浆漂至５０％新闻纸用浆白度，但要漂至高白度则比较困难。     

速生红麻纤维形态和制浆造纸性能研究

进行了一种速生红麻(hibiscus canniness L.)的纤维形态和制浆造纸性能的试验研究.该种速生红麻的纤维形态和化学组成表明该红麻适合用作造纸原料;全秆红麻采用烧碱-AQ法制浆可制得卡伯值16左右,得率46%左右的未漂浆,该纸浆有较好的漂白性能,容易用DQP和CEH漂序漂到84%ISO的白度.未漂浆和漂白浆均有较好的强度性能,在相同的打浆度或打浆转数下,DQP漂白浆的强度(尤其是撕裂指数)比CEH漂白浆好得多.     

马尾松热磨机械浆过氧化氢漂白工艺的优化

针对马尾松高得率浆过氧化氢漂后白度较低的现状,以南方速生材马尾松为原料,采用热磨机械制浆TMP和过氧化氢漂白。研究结果表明,工厂螯合预处理和脱水后的原浆样,经实验室洗涤或再次螯合预处理,漂后浆料的白度和残余过氧化氢均有所增加,这与浆中的金属离子含量有关。漂前进行NaBH4(硼氢化钠)预处理也可提高浆料的漂后白度,该过程中较合适的NaBH4用量和预处理时间分别为0.2%和2min。在与工厂相同的H2O2用量下,采用适当的预处理措施及优化漂白工艺后,漂后TMP浆的白度可达到71.79%ISO。     

过氧化氢漂白稳定剂对漂后蔗渣浆性能的影响

研究了非硅过氧化氢漂白稳定剂（PP-1＋PP-2）对蔗渣压力过氧化氢漂白浆强度性能和纤维形态的影响。研究结果表明：添加0．1％PP-1＋0．5％PP-2的稳定剂后,蔗渣压力过氧化氢漂白浆的白度达到85．0％ISO。与使用硅酸钠的漂后浆相比,非硅稳定剂（PP-1＋PP-2）漂后浆的抗张指数提高了2．6N．m／g,撕裂指数和耐破指数基本相当。（PP-1＋PP-2）作为稳定剂的蔗渣漂后浆的纤维长度、宽度和粗度与Na2SiO3漂后浆的相当,但纤维卷曲指数和细小纤维的含量低于Na2SiO3漂后的蔗渣浆。（P-1＋PP-2）漂后的蔗渣浆与Na2SiO3的漂后浆相比,纸浆的表面电荷和羧基含量较高,而Z电位较低。     

马尾松KP-AQ未漂浆中金属离子滞留性能的研究

用扫描电镜一能谱仪(SEM-EDAx)及原子吸收光谱仪研究了马尾松的金属离子分布及马尾松硫酸盐-蒽醌(KP-AQ)法未漂浆中金属离子的分布及滞留性能。结果表明,原料及未漂浆中都含有复杂的金属离子;未漂浆中的金属离子主要来源于原料,也受实验用水、金属设备及添加的化学药品等影响;不同金属离子由于其自身的性质不同,在未漂浆中滞留状态及滞留量不同。研究结果将为未漂浆的漂前预处理提供理论指导。     

光叶楮的制浆性能

对光叶楮木质部制备两段碱性过氧化氢化机浆(APMP)和化学浆(常规的硫酸盐法和烧碱-AQ法)及其烧碱-AQ浆料的可漂性能进行了初步探讨。比较分析了光叶楮木质部APMP与三倍体毛白杨APMP的浆料性能,及光叶楮木质部烧碱-AQ化学浆与毛白杨和加拿大杨硫酸盐化学浆的相关性能。     

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