邵宗平
,
熊国兴
,
杨维慎
无机材料学报
应用ＴＧ、ＤＴＡ、ＩＲ、ＸＲＤ和ＣＯ２－ＴＰＤ等技术对用。ｃｅｌｌｕｌｏｓｅ吸附法合成Ｌａ０．８Ｓｒ０．２ＣｏＯ3（ＬＳＣＯ）粉体的过程机理进行了研究．发现在制备过程中ｃｅｌｌｕｌｏｓｅ首先起着一种金属离子吸附剂的作用．在焙烧的前期阶段，ｃｅｌｌｕｌｏｓｅ先被部分氧化而在其骨架上出现了羧酸基团，并与金属离子发生螫合形成螯合离子．优化条件下，在低温合成了纯相ＬＳＣＯ粉体．然而若焙烧过程中产生的ＣＯ２不能及时地排出，会导致体相中碳酸盐的形成,从而需要高于８００℃的再焙烧才能获得纯相的ＬＳＣＯ粉体．
关键词:
Cellulose合成
,
synthesis
S.A.El-Henawii
,
S.M.Saad
,
I.M.El-Anwar
材料科学技术（英文）
The dielectric constants ε’, the dielectric loss ε” and the activation energy of dielectric relaxation of silylated cellulose were measured within the frequency range 105 to 107 Hz and the temperature range from 10 to 50°C. The test samples were activated cellulose with ethylene diamine, with sodium hydroxide and inactivated cellulose before and after silylation. The measurements were carried out using a multi-deka-meter. Cellulose molecules are more activated by treatment with ethylene diamine than with sodium hydroxide. Generally, silylation causes a marked decrease of the dielectric constant and dielectric loss, meanwhile the silylated samples are affected with the pretreatment of linters with sodium hydroxide and ethylene diamine.
关键词:
郭延柱
,
张丽
,
王兴
,
韩颖
,
周景辉
高分子材料科学与工程
在离子液体1-丁基-3-甲基咪唑氯盐(BmimCl)中,通过羟基与单体e-己内酯之间的开环接枝聚合反应(ROP),制备Cellulose-g-PCL两索性衍生物,利用红外光谱、核磁共振、X射线衍射、热重分析等技术对其结构和性能进行表征.通过改变催化剂种类和单体用量调节聚合物分子内疏水/疏水基团比例.荧光探针、透射电镜和动态光散射分析结果表明,Cellulose-g-PCL聚合物在水相中可自组装形成均一球形胶束,粒径位于纳米尺度范围内(30～130 nm),聚合物临界胶束浓度(CMC)较低(9.42～83.43 μg/mL).胶束粒径和CMC值均随聚己内酯的接枝率增加而降低.
关键词:
纤维素
,
两亲性
,
聚己内酯
,
自组装
,
胶束
邵宗平
,
熊国兴
,
杨维慎
无机材料学报
doi:10.3321/j.issn:1000-324X.2000.01.022
应用TG、DTA、IR、XRD和CO2-TPD等技术对用cellulose吸附法合成La0.8Sr0.2CoO3(LSCO)粉体的过程机理进行了研究. 发现在制备过程中cellulose首先起着一种金属离子吸附剂的作用. 在焙烧的前期阶段,cellulose先被部分氧化而在其骨架上出现了羧酸基团,并与金属离子发生螯合形成螯合离子. 优化条件下,在低温合成了纯相LSCO粉体. 然而若焙烧过程中产生的CO2不能及时地排出,会导致体相中碳酸盐的形成,从而需要高于800C的再焙烧才能获得纯相的LSCO粉体.
关键词:
cellulose
,
合成
,
La0.8Sr0.2CoO3
,
机理研究
Advanced Energy Materials
A simple and scalable method to fabricate graphene-cellulose paper (GCP) membranes is reported; these membranes exhibit great advantages as freestanding and binder-free electrodes for flexible supercapacitors. The GCP electrode consists of a unique three-dimensional interwoven structure of graphene nanosheets and cellulose fibers and has excellent mechanical flexibility, good specific capacitance and power performance, and excellent cyclic stability. The electrical conductivity of the GCP membrane shows high stability with a decrease of only 6% after being bent 1000 times. This flexible GCP electrode has a high capacitance per geometric area of 81 mF cm(-2), which is equivalent to a gravimetric capacitance of 120 F g(-1) of graphene, and retains >99% capacitance over 5000 cycles. Several types of flexible GCP-based polymer supercapacitors with various architectures are assembled to meet the power-energy requirements of typical flexible or printable electronics. Under highly flexible conditions, the supercapacitors show a high capacitance per geometric area of 46 mF cm(-2) for the complete devices. All the results demonstrate that polymer supercapacitors made using GCP membranes are versatile and may be used for flexible and portable micropower devices.
关键词:
carbon-nanotube electrodes;gel polymer electrolytes;double-layer;capacitors;energy-storage devices;lithium batteries;composite;films;performance
