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1.
A strategy based on covalent organic frameworks for ultrafast ion transport involves designing an ionic interface to mediate ion motion. Electrolyte chains were integrated onto the walls of one-dimensional channels to construct ionic frameworks via pore surface engineering, so that the ionic interface can be systematically tuned at the desired composition and density. This strategy enables a quantitative correlation between interface and ion transport and unveils a full picture of managing ionic interface to achieve high-rate ion transport. Moreover, the effect of interfaces was scaled on ion transport; ion mobility is increased in an exponential mode with the ionic interface. This strategy not only sets a benchmark system but also offers a general guidance for designing ionic interface that is key to systems for energy conversion and storage.  相似文献   
2.
发现在确定的热处理温度和时间下,随炉料中助熔剂NaCl-CdCl2,总含量的增加,CdS:Cu,In多晶的粒度分布变窄,数均粒径具有最大值,晶粒外型趋于规整且表面平滑.进而证明,多晶的结晶状态对其光电性能具有显著的影响.  相似文献   
3.
齐力  宋永贤 《应用化学》1993,10(6):66-70
环氧乙烷(EO)和环氧丙烷(PO)共聚体系的等温结晶前期符合Avrami方程。PO组分含量增加,Avrami指数n值由1.8到2.4,体系的结晶生长速率与共聚体系的组成和结晶度有关,EO/PO共聚体系的平衡熔点随PO含量的增加而降低。随Tc增大,△Hm与△Sm呈线性降低。  相似文献   
4.
研究了不同烃基乙烯基亚砜接枝聚乙烯醇(PVA-RVSO,R=Me,Et,t-Bu,Ph)膜对纯SO2、N2的透过性能以及SO2/N2混合气体的分离性能.结果表明上述膜对SO2具有高的选择性.对不同烃基乙烯基亚砜接枝膜进行了比较.  相似文献   
5.
张利华  于力 《应用化学》1994,11(4):40-44
用WAXD和SAXS方法研究了聚酰胺1010的聚集态结构和结晶结构的辐射损伤过程和机理。辐射交联与裂解主要在非晶区和结晶表面或中间相发生;辐射损伤并从这里开始,随辐射剂量增大,非晶化逐渐向晶区伸展,有氢键的(010)晶面损伤几率高于(100)晶面;辐射后效应导致新的交联与裂解生成,主要影响(010)晶面的形成与完善,使L100及Wc变小。  相似文献   
6.
The effects of chemical structure, i. e. side chain structure and their contents, on thepermeability of pure SO_2, N_2 and their mixture gases for the sulfoxide grafted poly (vinylalcohol) (RVSO-PVA) membranes have been investigated:where R=Me, Et, Pr, t-Bu and Ph. It was notable that introduction of sulfoxide group intoPVA side chain greatly enhanced the permselectivity of sulfur dioxide. SO_2 permeability andseparation factor of these polymers increased markedly as the size of side chain increased. Thesulfoxide content of the polymer also played an important role in the pure and mixture gasespermeation. Some explanations have been made to interpret this unique gas separation behaviour.  相似文献   
7.
8.
PolyHIPEs are highly porous, crosslinked polymer foams typically synthesized within high internal-phase emulsions (HIPEs). Two kinds of polyHIPEs including poly(styrene-divinylbenzene) [P(St-DVB)] and poly(methyl methacrylate-divinylbenzene) [P(MMA-DVB)] foams are synthesized in this work, which are fabricated from HIPEs template via radiation-induced polymerization at room temperature. Traditional free radical polymerization initiated by potassium peroxydisulfate (KPS) at 60 °C for producing polyHIPE P(St-DVB) foams is also conducted for comparison. It is found that the amount of emulsifier can be reduced greatly in the radiation-induced polymerization of HIPEs at room temperature, compared with the traditional polymerization approach. Besides, P(MMA-DVB) PolyHIPE foams with a fine microstructure of highly interconnected pores have been successfully fabricated via radiation-induced polymerization in this work, which is usually difficult to be prepared by thermal-initiation method because of the intermediate hydrophobicity of methyl methacrylate monomer. The influences of the fraction of internal aqueous phase and the concentration of emulsifier on the structure and performance of foams are carefully explored. The structure and compression strength of the foams are characterized by scanning electron microscopy and a mechanical testing machine, respectively.
Figure
Macroporous poly(styrene-divinylbenzene) and poly(methyl methacrylate-divinylbenzene) foams are synthesized from HIPEs template via radiation-induced polymerization at room temperature using a common surfactant Span 80.  相似文献   
9.
Ethyl acetate is an important chemical raw material and solvent. It is also a key volatile organic compound in the brewing industry and a marker for lung cancer. Materials that are highly selective toward ethyl acetate are needed for its separation and detection. Here, we report a trianglimine macrocycle ( TAMC ) that selectively adsorbs ethyl acetate by forming a solvate. Crystal structure prediction showed this to be the lowest energy solvate structure available. This solvate leaves a metastable, “templated” cavity after solvent removal. Adsorption and breakthrough experiments confirmed that TAMC has adequate adsorption kinetics to separate ethyl acetate from azeotropic mixtures with ethanol, which is a challenging and energy-intensive industrial separation.  相似文献   
10.
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