低浓度桉木KP浆臭氧漂白工艺的研究

对硫酸盐桉木浆进行氧脱木素后得到白度、黏度、卡伯值分别为49%ISO,755ml/g,11.1;浆料首先进行酸预处理,然后经过不同工艺条件的低浓度纸浆臭氧漂白,最后经过过氧化氢漂白。实验结果表明:不同工艺条件的低浓度纸浆臭氧漂白对漂后纸浆质量性能有明显的影响,对比不同工艺条件下臭氧—TCF漂白后纸浆性能得到桉木硫酸盐浆低浓臭氧漂白的最佳工艺条件为:Z段浆浓3%,p H小于2,臭氧用量0.8%。     

低浓亚麻浆臭氧漂白工艺的研究

在实验室条件下采用低浓纸浆臭氧漂白自动化反应设备进行低浓亚麻浆臭氧漂白工艺研究。以高浓纸浆、低浓纸浆臭氧漂白动力学为研究基础,从传质学角度分析低浓纸浆臭氧漂白的漂白速率,探讨了低浓纸浆臭氧漂白的可行性;同时对低浓亚麻浆臭氧漂白工艺进行了研究。实验结果表明,低浓亚麻浆臭氧漂白的最优工艺条件为:浆浓3%,臭氧用量1.0%,pH值为2,在最佳实验条件下得到的纸浆再进行过氧化氢漂白,最终得到的漂白亚麻浆白度为84%,黏度668 mL/g。     

木聚糖酶预处理对沙柳硫酸盐浆ECF漂白的影响

研究木聚糖酶预处理对沙柳硫酸盐浆ECF漂白性能的影响。结果表明,木聚糖酶预处理的最佳工艺条件为:温度50℃,pH7,浆浓8%,处理时间60min,酶用量10IU·g-1浆。木聚糖酶预处理可以提高沙柳硫酸盐浆的ECF漂白性能,使DED漂白浆的白度提高4.02%ISO。用木聚糖酶进行ECF漂白预处理不仅能够提高纸浆白度,有效降低漂白时的化学品用量,而且对纸浆强度影响并不明显。     

生物化学机械综合处理玉米秸秆制备高强纸浆纤维

玉米秸秆的髓由薄壁非纤维细胞构成,对制浆过程和纸页性能有负面影响。 本研究利用复合酶进行除髓预处理,然后进行常规碱法蒸煮和机械精制生产纸浆。 玉米秸秆下半部分的实验结果表明,秸秆除髓后的纸浆性能优异,纸浆得率介于 56.63% -79.94% ,抗张指数和撕裂指数分别介于 40.00-61.79N·m/ g 和 4.99-8.89mN·m²/ g。 整株玉米秸秆的纸浆得率和强度均低于秸秆下半部纸浆,纸浆得率介于38.48% -52.28% ,抗张指数介于33.64-52.22N·m/ g,撕裂指数介于 3.91-5.45mN·m²/ g。 在氢氧化钠用量为 10% 、蒸煮温度为 150℃ 、保温时间为60min、液比 1∶ 6 的优选制浆条件下,整株玉米秸秆所得纸的抗张指数、撕裂指数和耐破指数分别达 52.22N·m/ g、4.06mN·m²/ g 和 3.56kPa·m²/ g,远高于其他秸秆所得纸浆。     

硫酸盐蔗渣浆全无氯短序漂白生产工艺的研究

在尽可能模仿工厂实际生产条件下,采用酸处理-臭氧-过氧化氢(AZP)全无氯(TCF)短序清洁漂白生产流程对硫酸盐蔗渣浆漂白工艺参数进行研究。实验结果表明,硫酸盐蔗渣浆漂白最佳工艺条件为:Z段浆浓36%,pH值2.0,臭氧用量1.2%,臭氧浓度120 g/m~3,反应时间30 min,室温下进行;P段浆浓10%,过氧化氢用量3.0%,反应时间120 min,反应温度90℃,NaOH用量0.8%。最终得到的漂白硫酸盐蔗渣浆白度85.6%、黏度559 mL/g以及卡伯值3.6。同时,与传统漂白工艺流程(OQP_1P_2、OP_1ZP_2)相比,采用AZP短序漂后废水污染负荷最低,漂后废水COD_(Cr)为760 mg/L、BOD_5为90 mg/L以及色度为680 C.U.。     

低浓纸浆臭氧漂白经验模型的建立

以臭氧(O_3)用量作为自变量,纸浆卡伯值(K)、黏度和白度为响应值,研究了臭氧用量对纸浆漂白性能的影响,结果表明,臭氧最佳用量为0. 77%,此时漂白后纸浆卡伯值、黏度、白度分别为8. 1、658. 4 mL/g、41. 9%。计算漂白过程中脱木素选择性、单位臭氧消耗内卡伯值的降低率和白度的增加率,通过线性回归建立合适的数学模型,求出各因素随臭氧用量(O_(3CON))或卡伯值的预估函数。研究表明,硫酸盐阔叶木浆低浓臭氧漂白时,臭氧用量对卡伯值的关系采用指数模型较为合适,其方程为K=7.359(O_(3CON))~(-0.2318), R~2=0.9987。结合黏度、白度随卡伯值变化的方程,臭氧用量取0. 77%、其他条件一定时,通过该模型预测得到纸浆卡伯值、黏度、白度分别为7. 8、624. 2mL/g、42. 9%,该经验模型可预测并优化低浓硫酸盐阔叶木浆的臭氧漂白反应。     

纸浆浓度对臭氧漂白工艺的影响

在实验室条件下对阔叶木浆进行高浓、中浓、低浓臭氧漂白,并对漂白后纸浆的物理性能、结晶度、羧基含量等进行对比。结果表明,浆浓对漂白后纸浆性能有显著影响;当浆浓为3%时,漂白后纸浆白度为39.7%、黏度为745 mL/g、卡伯值为12.6。与中、高浓纸浆臭氧漂白相比,低浓臭氧漂白后的纸浆选择性最高为2.07。低浓臭氧漂白不仅可以防止纸浆黏度的下降,且一定程度上保护了纤维素的结晶区,臭氧利用率为96.5%,高于中、高浓纸浆臭氧漂白。     

金合欢木硫酸盐浆TCF工艺中臭氧漂白的研究

研究了经氧脱木素后金合欢木硫酸盐浆的臭氧漂白工艺。重点分析了不同臭氧用量对金合欢木硫酸盐漂白浆的卡伯值、粘度、白度和己烯糖醛酸含量的影响，并研究了纸浆卡伯值与粘度及白度之间的相互关系。结果表明：未漂浆卡伯值为6～8时，漂白时臭氧用量以6g／kg绝干浆为宜；纸浆卡伯值为5、5是臭氧脱木素作用和漂白作用的分界点。     

绿色糖单胞菌胞外酶漂白三倍体毛白杨硫酸盐浆的研究

用绿色糖单胞菌胞外酶对三倍体毛白杨硫酸盐浆进行生物预处理及后续漂白，摸索出最佳漂白工艺条件为：酶用量（以术聚糖酶为基准）30IU／g、温度60℃、时间120min、浆浓10％、pH值7．0，表明该胞外酶具有一定的热稳定性和耐碱性，这对纸浆漂白十分有利。再接后续漂白段，可进一步提高纸浆白度和粘度，降低卡伯值，改善纸浆的可漂性．实现TCF漂白。     

硫酸盐竹浆臭氧漂白的研究

对硫酸盐竹浆臭氧漂白的影响因素进行了研究，并通过正交实验得出臭氧单段漂白的最佳工艺条件为：浆浓10％，臭氧用量0．5％，温度20℃和pH值2。此条件下，漂后浆白度可达68．7％SBD，粘度为887mL／g。另外还进一步还探讨了竹浆H2O2强化的臭氧漂白工艺。     

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