国内外超级电容器隔膜老化性能对比分析

隔膜作为超级电容器的关键部件,其老化前后性能的对比研究对于超级电容器的使用寿命具有重要意义。本研究从隔膜纸张的物理性能和电化学性能角度,分析评价国产超级电容器隔膜和进口超级电容器隔膜老化前后的性能差异。结果表明,国产隔膜各项性能与进口隔膜相当,测试各项结果合格,可满足超级电容器的基本使用要求。     

超级电容器隔膜纸的特性和发展趋势

主要介绍了超级电容器对隔膜纸的性能要求,隔膜纸的种类和制备方法;分析了几种隔膜纸产品的特点,并提出了超级电容器隔膜纸的未来发展趋势。     

超级电容器隔膜制备及其孔隙率对电化学性能的影响

根据隔膜性能要求,采用低浓轻刀打浆和高浓磨浆两种方式制备微纤化纤维,对制备的隔膜进行了物理性能检验,并针对不同孔隙率隔膜制备的超级电容器进行了电化学性能分析。结果表明,与低浓轻刀打浆方式相比,高浓磨浆可以有效地保留纤维长度,提高纤维长径比,在打浆度为85°SR时,隔膜抗张强度达到0.55kN/m,孔隙率为67%,葛尔莱透气度为41.7μm/(Pa·s)。随着隔膜孔隙率的提高,超级电容器的比电容在0.5 A/g电流密度下逐渐增大;孔隙率为68%的隔膜制备的超级电容器循环伏安特性曲线呈明显的矩形,表现出良好的电容性能。     

超级电容器用原纤化天丝隔膜的制备及性能研究

通过对天丝短切纤维进行打浆处理,获得了具有不同原纤化程度的天丝纤维,并结合湿法成形技术制备得到原纤化天丝隔膜。探究了纤维几何尺寸和形貌对隔膜孔隙结构的影响,对不同孔隙结构隔膜制备的超级电容器电化学性能进行了分析。结果表明,天丝纤维经过不同打浆转数处理后,纤维尺寸和隔膜孔隙结构发生了明显变化。随着打浆转数的增加（20000～250000转）,粗纤维比例显著降低,质均纤维长度从2.29 mm降至0.76 mm。孔隙率从81.2%降至66.3%,隔膜平均孔径从1.20μm降至0.27μm,隔膜厚度从47.7μm降至26.0μm,但不同原纤化天丝隔膜制备的超级电容器的阻抗、比容量、能量密度和功率密度变化并不明显。     

Dreamweaver和P.H.Glatfelter实现超级电容器隔膜材料规模化生产

<正>Dreamweaver和P.H.Glatfelter于2015年底完成了Dreamweaver TitaniumTM纳米纤维基超级电容器隔膜材料的规模化生产。与Glatfelter的合作使Dreamweaver成为亚洲以外唯一的超级电容器隔膜材料生产商。该公司超级电容器隔膜材料的设计生产能力是7000万m2/a,2016年将增加产能来满足市场需求的增长。     

无纺布型锂电隔膜

正纸基freshman纸基功能材料2017-12-19报道:湿法无纺布(造纸)隔膜,作为重要的一种隔膜类型,可以应用到超级电容器、锂离子电池、镍氢电池和一次性电池。该类隔膜以其孔隙率高、耐高温、安全性高等优势在动力型锂电池和超级电容器领域引起了众多关注。目前全球仅有美、日、德少数厂家实现了批量生产。我国许多单位     

石墨烯复合材料超电容性能的研究

活性电极材料的好坏是影响超级电容器性能的决定因素,基于石墨烯的复合材料是最重要的超级电容器活性电极材料的一种,该类材料用作超级电容器的电极材料时具有环境友好、成本低、比电容量高、充/放电时间快和循环稳定性高等优点。文章概述了近年来不同石墨烯复合材料,包括石墨烯/金属氧化物、石墨烯/导电聚合物、石墨烯/碳材料、石墨烯/金属硫化物和基于石墨烯的三元复合物等,用于超级电容器的电容性能,并对其进行了展望。     

柔性纺织纤维基超级电容器研究进展

为促进纤维基超级电容器在柔性能量存储领域的应用,以纺织纤维原料为类别,对高性能纤维(碳纳米管纤维,石墨烯纤维)、天然纤维、合成纤维基超级电容器的研究进行综述。在此基础上,对不同类型的纤维基超级电容器性能分析对比,总结各种纤维基超级电容器的优缺点。结果表明,高性能纤维基超级电容器的纤维结构、传荷位阻、离子扩散速率决定了纤维比能量及循环寿命,但该类型纤维基超级电容器受限于纤维材料的力学性能,后续织造较为困难;天然、合成纤维可满足后道纺织工艺对纤维的力学要求,易与纺织品结合成为整体,其储能大小受活性物质结构、密度、电荷传递协同效应影响较大。最后,针对柔性纤维基超级电容器研究存在的问题进行说明并对未来需要攻克的重点难点进行分析及展望。     

木质素基超级电容器碳电极研究进展

超级电容器是功率密度高、充放电速度快和安全可靠的绿色储能装置,其电极材料是超级电容器性能优劣的关键。可再生木质素具有含碳量高、来源广泛和成本低等优点,其通过活化、模板和纺丝等方法可制备出性能优异的木质素基超级电容器碳电极,具有较好的发展前景。本文主要介绍了木质素基超级电容器活性炭电极、模板炭电极和碳纤维电极,并对木质素基超级电容器碳电极的研究进行总结与展望,为新型高性能超级电容器电极材料的结构设计与制备提供参考。     

碳纳米管/Ni/聚苯胺纤维状超级电容器的制备及其电化学性能

为提高纤维状超级电容器的电容性能,将碳纳米管(CNT)纤维进行阳极氧化预处理、金属化处理和电沉积聚苯胺后得到不同的电极材料,分别将CNT、CNT/聚苯胺(CNT-PANI)、CNT/阳极氧化/聚苯胺(CNT-O-PANI)、CNT/阳极氧化/金属化/聚苯胺(CNT-O-Ni-PANI)这4种电极材料组装纤维状超级电容器,并对其结构和电化学性能进行研究。结果表明：经过阳极氧化和金属化处理后,聚苯胺均匀、紧密地分散在碳纳米管纤维表面,并且无团聚、结块等现象;CNT-O-Ni-PANI电极材料制备的超级电容器具有优异的储能性能,其比电容和能量密度远高于其他3种电极材料;在1 A/g的电流密度下,其比电容和能量密度分别为357.8 F/g和178.9 W·h/kg;在10 mV/s的扫速下,其比电容高达1 246.3 F/g;采用CNT-O-Ni-PANI所制备的超级电容器稳定性能较好,在5 A/g的电流密度下,经过10 000次恒流充放电循环后,其电容保持率仍高达99.7%。     

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