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摄像靶用Sb_2S_3:Sb的结构模型及其共熔合成机理
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作者 李英杰 《光电子技术》 CAS 1993年第3期60-67,共8页
认为“Sb_2S_3是离子键化合物”这一结论值得商榷。提出Sb_2S_3系不等性SP杂化弱极性共价键结合,形成六元环状结构,并在一维空间扩展为带状构形。在此带状分子链间则以键能较弱的Vanderwaal键相维系,使之聚集在晶体的平行窄条中。Sb_2S_... 认为“Sb_2S_3是离子键化合物”这一结论值得商榷。提出Sb_2S_3系不等性SP杂化弱极性共价键结合,形成六元环状结构,并在一维空间扩展为带状构形。在此带状分子链间则以键能较弱的Vanderwaal键相维系,使之聚集在晶体的平行窄条中。Sb_2S_3Sb中的:Sb,在很窄的含量范围内以弱次级键“挂靠”在Sb_2S_3分子上,而超过此含量范围的:Sb则以机械状态混合其中。这一完整的Sb_2S_3:Sb的结构模型及其共熔合成机理的分析,为摄像靶用Sb_2S_3:Sb材料成份的选择和合成工艺的制订,提供了重要的、不可缺少的理论依据。 展开更多
关键词 摄像靶 化学热力学 离子键合物
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COMPATIBILITY OF POLY (STYRENE-B-2-VINYL PYRIDINE)/IONOMER BLENDS BASED ON ION-LIGAND INTERACTION 被引量:1
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作者 GUO Tianying HAO Guangjie +1 位作者 SONG Moudao ZHANG Banghua 《Chinese Journal of Reactive Polymers》 2002年第1期26-31,共6页
In this work, DSC and SEM studies indicate that ion-ligand interaction can be utilized to enhance the interaction of poly (styrene-block-2-vinyl pyridine)[P (S-b-2VP)] and polyethylene based ionomer (Surlyn). The comp... In this work, DSC and SEM studies indicate that ion-ligand interaction can be utilized to enhance the interaction of poly (styrene-block-2-vinyl pyridine)[P (S-b-2VP)] and polyethylene based ionomer (Surlyn). The compatibility for this blending system can be improved by this special interaction and 20/80 wt is the optimum blending composition with good compatibility. FTIR results further certify that strong interactions exist in the blending system. 展开更多
关键词 Diblock copolymer IONOMER BLENDING Compatibility
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Quaternary phosphonium polymer-supported dual-ionically bound[Rh(CO)I_(3)]^(2-)catalyst for heterogeneous ethanol carbonylation
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作者 Zhou Ren Yang Liu +4 位作者 Yuan Lyu Xiangen Song Changyong Zheng Zheng Jiang Yunjie Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第4期606-617,共12页
A single-Rh-site catalyst(Rh-TPISP)that was ionically-embedded on a P(V)quaternary phosphonium porous polymer was evaluated for heterogeneous ethanol carbonylation.The[Rh(CO)I_(3)]^(2-)unit was proposed to be the acti... A single-Rh-site catalyst(Rh-TPISP)that was ionically-embedded on a P(V)quaternary phosphonium porous polymer was evaluated for heterogeneous ethanol carbonylation.The[Rh(CO)I_(3)]^(2-)unit was proposed to be the active center of Rh-TPISP for the carbonylation reaction based on detailed Rh L3-edge X-ray absorption near edge structure(XANES),X-ray photoelectron spectroscopy(XPS),and Rh extended X-ray absorption fine structure(EXAFS)analyses.As the highlight of this study,Rh-TPISP displayed distinctly higher activity for heterogeneous ethanol carbonylation than the reported catalytic systems in which[Rh(CO)_(2)I_(2)]^(-)is the traditional active center.A TOF of 350 h^(-1)was obtained for the reaction over[Rh(CO)I_(3)]^(2-),with>95%propionyl selectivity at 3.5 MPa and 468 K.No deactivation was detected during a near 1000 h running test.The more electron-rich Rh center was thought to be crucial for explaining the superior activity and selectivity of Rh-TPISP,and the formation of two ionic bonds between[Rh(CO)I_(3)]^(2-)and the cationic P(V)framework([P]^(+))of the polymer was suggested to play a key role in firmly immobilizing the active species to prevent Rh leaching. 展开更多
关键词 Heterogeneous ethanol carbonylation Single-site catalyst Carbonylation active center [Rh(CO)I_(3)]^(2-) Ultrastable dual-ionically bound immobilization Porous ionic polymer
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