文献汇报PPT模版.ppt
在此输入标题副标题 Introduction Experimental Results and discussion Conclusion IntroductionChitin(poly-(1,4)-N-acetyl-d-glucosamine)is the second most abundant natural biopolymer after cellulose and a basic structural component of fungi and yeast cell walls,as well as of numerous invertebrates.自然界中含量仅次于纤维素的一种天然高聚物The chitin-based scaffolds recently found by our groups in marine sponges are three-dimensional networks of tube-like interconnected fibers with a diameter of about 100 m in the case of Aplysina aerophoba.支架是通过直径约100m的管状纤维连接形成的三维网络The adsorption behavior was tested in lifelike concentration ranges.We further attempted to desorb the uranyl in order to recover the sponge chitin and make it reusable.The kinetics of the adsorption process were examined to determine the time needed for the adsorption.The interaction mechanisms between chitin and uranyl were examined with solid-state NMR,infrared,Raman as well as time-resolved laser fluorescence spectroscopy.ExperimentalMarine sponge Aplysina aerophoba：collected in the Adriatic Sea(Kotor Bay,Montenegro)and dried on air.NaOH platelets：purchased from Grssing(99%).Concentrated acetic acid：purchased from VWR(HPLC grade).-Chitin：purchased from Carl Roth GmbH(depure).NaClO42H2O,NaOH and HCl：purchased from Merck(analytical grade).Concentrated HNO3：purchased from Carl Roth GmbH(analytical grade)and distilled before usage.A 1000 mg/l rhodium solution：purchased from Merck(ICP-MSstandard).UO2(ClO4)2：0.102 MIonic strength：0.5 M(NaClO4)Results and discussion The sponge chitin is completely acetylated within the limits of experimental error.（甲基的相对强度为103%）The extracted fibers consist of concentrically arranged and loosely packed tubular structures with hollow spaces in between.（由松散的同心排列的管状结构组成）Chitin networks dried were thus not useful for adsorption experiments any more.Freeze-dried chitin maintained its threedimensional shape.The specific surface of freeze-dried samples was 4 m2/g.However,uranyl adsorption did not yield reproducible results for freeze-dried sponge chitin.The surface area value might be higher in hydrated chitin.（水合甲壳素的比表面积值可能更高）The hydrated sponge chitin from A.aerophoba still contained approx.90 wt%water.It is likely that a significant part of the water is stored in the spaces within the fibers.（水是存储在在纤维空间的一个重要组成部分）Chitin networks from marine sponges were shown to be promising materials for the purification of water from uranium contamination.Sponge chitin effectively sorbs uranyl.In summary,A.Aerophoba sponge chitin is a material with favorable properties for water purification by both industry and consumers.Conclusion
