杨木APMP制浆化学预处理废液中有机物的分析

研究了不同化学预处理条件对APMP废液中木素和糖类物质浓度的影响。结果表明,化学预处理过程中化学药剂NaOH用量、H₂O₂用量和Na₂SiO₃用量对化学预处理废液中木素和糖类物质浓度的变化有不同影响,影响程度由大到小依次为NaOH用量＞H₂O₂用量＞Na₂SiO₃用量,其中NaOH用量和H₂O2用量对木素和糖类物质浓度的变化有重要影响,Na₂SiO₃用量无明显影响。化学预处理温度对化学预处理废液中木素和糖类物质浓度的影响程度明显大于化学预处理时间。在化学预处理过程中,NaOH用量、H₂O₂用量和化学预处理温度是影响杨木APMP制浆化学预处理废液中木素和糖类物质浓度的重要因素。     

微咸水灌溉条件下施用不同改良剂对盐渍化土壤盐分离子分布的影响--测试文章

利用5种不同的土壤改良剂,对矿化度在2～3 g·L^-1的微咸水灌溉棉田土壤进行改良效果研究。结果表明：五种改良剂均降低土壤pH值和总盐含量,并能有效控制土体Na⁺、Ca²⁺、SO₄^2-、HCO₃^-积累;其中,磷石膏能显著降低土体Na⁺、Ca²⁺、SO₄^2-总含量（P＜0.05）,DS1997能显著降低土体Na⁺、HCO₃^-总含量（P＜0.05）,酸碱平衡剂显著降低土体Ca²⁺、SO₄^2-总含量（P＜0.05）,禾康改良剂有效控制土体SO₄^2-、HCO₃^-含量;改良剂对土体中Cl^-改良效果不显著（P＞0.05）。研究得出：微咸水灌溉导致土壤pH值升高和含盐量增加,造成土壤盐分的积累;土壤改良剂可有效减少微咸水灌溉引起的盐分积累,改善土壤理化特性和盐分离子分布。     

电Fenton技术深度处理造纸废水

采用电Fenton技术深度处理二级生化后的造纸废水,以色度去除率和COD去除率为主要考察指标,研究不同因素对造纸废水深度处理效果的影响。反应的最佳条件为：反应时间120 min、初始pH值=3、电压12 V、Fe²⁺浓度0.8 mmol/L、H₂O₂浓度0.8 mmol/L、极板间距10 cm、电解质Na₂SO₄浓度6 g/L。最佳反应条件下,电Fenton法对造纸废水的色度去除率和COD_Cr去除率分别达到89.5%和68.4%。动力学分析表明,电Fenton技术对造纸废水COD的降解符合一级反应动力学规律,一级反应速率常数为k=0.2072 min^-1。     

藕渣纤维素的碱法提取工艺优化及性能测定

目的 优化藕渣纤维素的提取工艺,并通过系列表征证明该纤维素的形貌结构及理化特性。方法 以纤维素的含量为指标, 以NaOH浓度、Na₂SO₃浓度和提取温度为考察因素进行单因素实验, 结合Box-Behnken 响应面实验对提取工艺进行优化。并对提取纤维素进行组分分析和形貌结构表征。结果 响应面优化结果显示, NaOH浓度、Na₂SO₃浓度和提取温度对藕渣纤维素的含量均具有显著影响(P<0.05)。确定最佳提取工艺条件为NaOH浓度1.25 M、Na₂SO₃浓度1 M、提取温度80 ℃,此条件下纤维素含量84.31%,其中淀粉含量为0.8%、蛋白质含量为2.75%。红外数据表明纯化样品中半纤维素和木质素的特征峰明显减弱,具有典型的纤维素峰,证明了有效提取了纤维素样品；X射线衍射结果表明藕渣和提取的纤维素衍射曲线差别较大,且藕渣纤维素的衍射峰位置与已报道纤维素基本一致,证明所使用的提取方法并未改变藕渣纤维素的结晶结构；扫描电镜分析表明木质素和半纤维素被除去后纤维素裸露表面发生聚集形成褶皱结构,热分析表明藕渣纤维素的最佳热分解温度为265 ℃,所提取的纤维素具有较好的热稳定性。 结论 该碱法提取工艺方法简单高效,为藕渣等农产品加工副产物的开发利用提供了理论依据。     

磷酸盐-硅系纳米浆料助剂的分散稳定性

为了研究纳米浆料助剂的稳定性对淀粉浆料性能的影响,分别以Na₃PO₄,Na₄P₂O₇, (NaPO₃)₆ 和 Na₅P₃O₁₀为分散剂制备了纳米SiO₂浆料助剂,通过离心透光率、沉降积等指标表征该磷酸盐-硅系纳米浆料助剂的分散稳定性;研究它的分散稳定性对淀粉浆液、浆膜及黏附性能的影响。实验表明,Na₃PO₄,Na₄P₂O₇,(NaPO₃)₆和Na₅P₃O₁₀的分散稳定能力依次增强,质量分数分别为0.5%,4%,8% 和 10%时分散效果最佳;该种助剂对淀粉浆液性能没有显著影响,对浆膜断裂强度及黏附性能的促进作用随着分散体系稳定性的提高而增强;以Na₅P₃O₁₀为分散剂的纳米浆料助剂对淀粉浆料性能的促进作用最显著。     

石英纤维的表面改性及分散特性研究

本研究通过对石英纤维进行酸/碱溶液和表面活性剂结合的预处理方式,改善其在水中的分散性,重点研究了酸溶液、碱溶液、表面活性剂的种类及浓度对石英纤维分散特性的影响。结果表明,预处理后的石英纤维具有良好的分散特性,其湿法成形的纸张（石英纸）表面平整、无明显纤维絮聚成团。通过H₂SO₄和聚氧化乙烯（PEO）2种预处理方式的结合,石英纤维在水中的分散性较佳。当H₂SO₄的pH值为3、PEO的质量浓度为0.1 g/L时,预处理后的石英纤维在水中的分散性最佳,石英纸的匀度指数可达89.1,较未处理原纤维抄造的石英纸匀度指数（222.6）降低了60%。     

亚甲基蓝褪色光度法测定小麦粉中的痕量溴酸钾

利用KBrO₃在H₂SO₄介质中能氧化褪色亚甲基蓝的特性,建立了亚甲基蓝褪色光度法测定小麦粉中痕量KBrO₃的新方法。试验结果表明,在测定波长为665 nm,2.0 mol/L H₂SO₄溶液为1.7 ml,0.05 g/L亚甲基蓝用量为1.5 ml,1.0%KBr用量为2.0 ml,加热温度为60℃,反应时间为5 min条件下,该方法的线性范围为0.06～0.50 mg/L,检出限为0.01 mg/kg,定量限为0.03 mg/kg。该方法用于小麦粉中痕量KBrO₃的测定,样品回收率在94.3%～105.7%,相对标准偏差RSD＜5%,试验结果能满足小麦粉中痕量溴酸盐测定的要求。      

造纸法烟草薄片碳化硅膜净化系统清洗工艺研究

本研究对造纸法烟草薄片提取液成分进行了分析,筛选确定了提取液分离净化用碳化硅膜净化系统合适的无机酸清洗剂,研究不同浓度下,该无机酸清洗剂的清洗效果,优化了无机酸清洗剂与碱性清洗剂的组合;在原清洗流程基础上增加了化学浸泡流程,通过对比2种化学浸泡清洗工艺,优选确定了合适的化学浸泡工艺。结果表明：①造纸法烟草薄片提取液中有机物含量约75%;②采用质量分数10%的NH₂SO₃H溶液清洗生产线膜净化系统后,膜通量恢复至原始通量的86.05%,满足膜净化系统清洗需求;③较优的清洗剂组合为质量分数6%的NH₂SO₃H溶液和质量分数6%的NaOH溶液;④合适的化学浸泡工艺条件为：NaOH溶液质量分数10%,每4 h碱液泵启动1次,碱液泵单次运行时长1 h,化学浸泡总时长24 h。优化后,造纸法烟草薄片生产线膜净化系统运行周期最高增加至14.0 h;膜通量恢复比例最高增加至94.00%;日常化学清洗消耗时间降至89 min。     

游离SO2、溶解氧浓度对葡萄酒颜色及花色苷含量的影响

目的：探索不同浓度溶解氧与游离SO₂对赤霞珠干红葡萄酒在陈酿中的颜色及相关参数的影响。方法：以新疆吐鲁番鄯善县新葡王酒庄赤霞珠干红葡萄酒为酿制试材,在葡萄酒陈酿过程中通过添加不同浓度的游离SO₂与溶解氧,观察其对葡萄酒色度、色调和花色苷含量等指标的影响。结果：溶解氧与游离SO₂浓度较低时葡萄酒呈鲜艳的酒红色,充氧量为2 mg/(L·30 d)时可促进葡萄酒中花色素苷、单宁适度聚合,改善葡萄酒品质;游离SO₂质量浓度为15~30 mg/L时对葡萄酒的色调值影响不大,但对色度影响较为明显,超过30 mg/L时会使葡萄的酒颜色逐渐显橙色。结论：赤霞珠干红葡萄酒陈酿的适宜游离SO₂质量浓度为25 mg/L,充氧量为2 mg/(L·30 d)。     

碳酸钠对纸质文献超声雾化脱酸效果的研究

本研究使用易溶性水相脱酸剂Na₂CO₃溶液,通过超声雾化对纸质文献进行脱酸处理,对其可超声雾化质量分数范围、超声雾化速率、雾化量、雾化稳定性、雾化粒径、脱酸均匀性等效果进行了探究。结果表明,Na₂CO₃溶液可超声雾化质量分数范围为0~12%;质量分数高的Na₂CO₃溶液超声雾化较为困难,超声雾化速率小;Na₂CO₃溶液质量分数越低,超声雾化速率越不稳定;随Na₂CO₃溶液质量分数的升高,超声雾化平均粒径递增且变化幅度不大。在实验条件范围内,相对于其他质量分数,质量分数6%的Na₂CO₃溶液雾化量最大,超声雾化稳定性高,脱酸均匀性最好,脱酸一段时间后,纸质文献仍能保持较好的脱酸效果。     

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