金属-有机框架/纤维素复合材料研究进展

金属-有机框架（MOFs）是由金属离子和有机配体构成的具有一维、二维、三维结构的多功能晶态材料,MOFs本身的晶型结构决定了它们大多以粉末状存在,在回收、加工成型等方面受到限制。选择天然的或改性的柔性纤维素基材作为沉积MOFs的理想基底,一方面MOFs可赋予纤维素基材许多新的功能,实现纤维素的高值化利用;另一方面纤维素基材可为MOFs提供更广阔的利用空间,实现MOFs的多级开发利用。本文综述了MOFs/纤维素复合材料的研究进展,包括基底材料的选择、制备方法、性能及应用等。     

导电聚合物-纤维素纤维复合材料研究新进展

导电聚合物与纤维素纤维的复合可实现功能互补,相应复合材料具有较大利用潜力。本文概述了近年来导电聚合物 纤维素纤维复合材料研究的一些新进展。导电聚合物 纤维素纤维复合材料的制备方法有：原位液相化学聚合法、气相化学聚合法、喷墨打印法、聚电解质吸附法、层层自组装法、吸附胶团聚合法、电化学聚合法等。不同方法各具特色,亦有交叉性与重叠性。其中,原位液相化学聚合法因制备过程简单、成本较低和环境友好而备受关注,已有的研究进展为复合材料在功能纸和水体净化材料等方面的应用奠定了理论基础。在对新进展进行概述的基础上,提出了今后导电聚合物 纤维素纤维复合材料具有发展潜力的研究方向。     

金属有机框架纤维膜复合材料的制备及其在水质净化中的应用

摘 要：随着工业进步和社会发展,水污染已成为全球的主要威胁,不止影响生态环境,还会通过食物链累积效应,从而威胁食品质量安全。金属有机骨架材料(metal-organic frameworks,MOFs)是一种多孔晶体材料,具有多孔性、大比表面积等优势。近几年,通过静电纺丝技术将MOFs负载到高孔隙率、高柔韧性的纳米纤维(NFMs)上,有望克服MOFs材料不易循环利用的缺点,同时这一新兴材料合成技术在水质净化领域的研究尚处于起步阶段,但是其发展潜力已引起众多学者关注。本文综述了金属有机框架纳米纤维膜合成方法、膜性能参数及其在水质净化方面的初步应用,并对该复合材料未来发展趋势进行展望,以期为该复合材料进一步的研究发展提供参考。     

Ag/RGO/纤维素复合纸的制备及性能研究

本研究将Ag/纤维素和氧化石墨烯（GO）/纤维素均匀混合,利用抽滤工艺和水合肼还原法制备Ag/RGO/纤维素复合纸。利用X射线光电子能谱仪和扫描电子显微镜表征了Ag/RGO/纤维素复合纸的结构和形貌,并研究了复合纸的导电性、机械强度、热稳定性和抗菌活性。结果表明,Ag/纤维素和RGO/纤维素紧密结合在一起,Ag/RGO/纤维素复合纸的电导率为0.042 S/cm,低于Ag/纤维素纸的电导率。Ag/RGO/纤维素复合纸的杨氏模量和断裂伸长率分别为489 MPa和4.5%,相比纤维素纸分别提高了12.9%和7.1%;第二阶段热解开始温度为300℃,相比纤维素纸提高了40℃。Ag/RGO/纤维素复合纸具有优良的抗菌活性,对大肠杆菌和金黄色葡萄球菌的抑菌圈直径分别为14 mm和9 mm。     

纳米纤维素/纳米铜复合材料制备及应用研究进展

纳米纤维素/纳米铜复合材料兼顾了纳米纤维素的优异力学和光学性能、高比表面积、低热膨胀系数、环境友好等特性以及铜的导电、导热、抗菌等性能,近年来在锂离子电池、多相催化、抗菌领域有广泛的应用。本文首先分别介绍了纳米纤维素和纳米铜的制备方法和理化特性;重点阐述了纳米纤维素/纳米铜复合材料的制备方法（物理沉积法和化学还原法）、理化特性（导电性能、催化性能和抗菌性能）及其在电子器件、催化剂和抗菌材料的应用进展;最后总结了纳米纤维素/纳米铜复合材料存在的问题并展望了未来的发展趋势。     

水相中GOx@ZIF-7/PDA的制备及酶学性能研究

原位包埋策略因制备条件温和、操作简单，被普遍应用在酶-金属有机骨架(metal-organic frameworks, MOFs)生物复合材料的制备中。但只有少部分MOFs能在水相中通过原位包埋法合成酶-MOFs生物复合材料。该研究首次在水相中采用原位包埋法将葡萄糖氧化酶(glucose oxidase, GOx)封装在ZIF-7(zeolitic imidazolate frameworks-7)载体中，并在所得的GOx@ZIF-7生物复合材料上合成了亲水性的聚多巴胺(polydopamine, PDA)修饰层，得到GOx@ZIF-7/PDA。采用单因素试验优化了GOx@ZIF-7/PDA的制备条件。结果表明，固定化pH值为7.0,酶质量浓度为5 g/L,苯并咪唑(benzimidazole, Bim)浓度为50 mmol/L,Zn²⁺与苯并咪唑的摩尔比为1∶9,固定化温度为35℃,固定化时间为40 min,多巴胺的最佳质量浓度为2 g/L的条件下，GOx@ZIF-7/PDA具有最高酶活力回收率为(43.34±2.00)%。与游离酶相比，GOx@ZIF-7/PD...     

MCC/MOFs抗菌复合材料的制备及表征

采用原位沉积法将两种金属有机框架化合物（Metal-Organic Frameworks,MOFs）MOF-5和1,3,5-均苯三甲酸铜（Ⅱ）（HKUST-1）负载在微晶纤维素（MCC）上,制备出MCC/MOF-5和MCC/HKUST-1二元复合材料以及MCC/MOF-5/HKUST-1和MCC/HKUST- 1/MOF-5三元复合材料;分别采用傅里叶变换红外光谱仪（FT-IR）、X射线衍射仪（XRD）及扫描电子显微镜（SEM）分析复合材料的化学组成和微观形貌;以大肠杆菌（Escherichia coli, E-coli）为测试菌种,通过测定抑菌圈直径检测复合材料的抗菌性能。结果表明,实验成功制备出了表面覆盖有立方体结构的MOF-5和棒状结构的HKUST-1的二元和三元复合材料;由于金属离子的协同抗菌作用,三元复合材料较二元复合材料对大肠杆菌具有更优异的抗菌性能;由于Zn²⁺的抗菌能力大于Cu²⁺,MCC/HKUST-1/MOF-5的抗菌效果较MCC/MOF-5/HKUST-1好。     

MOFs衍生碳基复合吸波材料的研究进展

电磁吸波材料对于防护电磁辐射危害是极为有效的一种手段,吸波材料所具有的吸波性能对军用和民用都有重大意义。Metal-organic frameworks(MOFs)衍生碳基复合材料是一种新型吸波材料,具有合成工艺简单、热稳定性好、比表面积大、孔隙率高等优点。本文简要介绍电磁吸波机理,综述碳基复合吸波材料研究现状,分析MOFs衍生碳基复合材料在电磁吸波领域研究进展,展望MOFs衍生碳基复合吸波材料未来发展前景。     

双醛羧甲基纤维素/三聚氰胺树脂对模拟染料废水的吸附效果

为获得具备优良吸附特性的废水处理吸附材料,以羧甲基纤维素为原料,经高碘酸钠氧化合成双醛羧甲基纤维素,再与三聚氰胺反应制备双醛羧甲基纤维素/三聚氰胺复合材料。研究复合材料对水溶液中直接湖蓝5B的去除效果,并分析了溶液pH值、染料初始质量浓度、氯化钠质量浓度、吸附剂质量浓度、吸附时间对吸附效果的影响。结果表明:双醛羧甲基纤维素/三聚氰胺复合材料对直接湖蓝5B有良好的吸附性能,在直接湖蓝5B质量浓度为0.2 g/L,pH值为4.0,氯化钠质量浓度为40 g/L,吸附剂质量浓度为4 g/L,吸附时间为60 min时,脱色率达到99.2%。经红外表征双醛羧甲基纤维素/三聚氰胺复合材料存在席夫碱性质的共价键,并同时存在静电作用力。     

羟基磷灰石纳米颗粒的合成及其复合材料的应用研究进展

羟基磷灰石（HAP）是脊椎动物骨骼和牙齿的主要矿物成分。由于具有优良的生物相容性、无毒无污染、离子交换性和耐高温等特性,HAP纳米颗粒（HAP NPs）在生物医学、造纸和吸附催化等领域具有非常广泛的应用。本文首先简述了HAP NPs的结构特征及合成路线,重点综述了近年来HAP NPs/纤维素基复合材料的合成进展及在生物医学、吸附和造纸等领域的最新应用进展,并对HAP复合材料在功能材料领域未来的发展趋势做了展望。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Analysis on Economic Indicators from 62 Enterprises in Printing Machinery Industry in Q1 2014

Operation of printing machine industry was still unsatisfactory in the first quarter of 2014.Analysis on operation of printing machine industry.a.Market demand was not strong;sales of product undulated and declined.According to the statistics,the total industrial output value fell by 19.28% in the first quarter of 2014 than the average quarter value in 2013; industrial added value decreased by 4.16%; sales revenue dropped by 22.83%. h. Business operation of enterprises was in poor condition. c. R＆D of new products is an important transformation guarantee for enterprises. d. To take self explore new ways upgrading advantages,and explore new ways.