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| 1 | Investigation of reinforcement of the modified carbon black from wasted tires by nuclear magnetic resonance显示文摘Pyrolysis has the potential of transforming waste into recyclable products. Pyrolytic carbon black (PCB) is one of the most important products from the pyrolysis of used tires. Techniques for surface modifications of PCB have been developed. One of the most significant applications for modified PCB is to reinforce the rubber matrix to obtain high added values. The transverse relaxation and the chain dynamics of vulcanized rubber networks with PCB and modified PCB were studied and compared with those of the commercial carbon blacks using selective 1H transverse relaxation (T2) experiments and dipolar correlation effect (DCE) experiments on the stimulated echo. Demineralization and coupling agent modification not only intensified the interactions between the modified PCB and the neighboring polyisoprene chains, but also increased the chemical cross-link density of the vulcanized rubber with modified PCB. The mechanical testing of the rubbers with different kinds of carbon blacks showed that the maximum strain of the rubber with modified PCB was improved greatly. The mechanical testing results confirmed the conclusion obtained by nuclear magnetic resonance (NMR). PCB modified by the demineralization and NDZ-105 titanate coupling agent could be used to replace the commercial semi-reinforcing carbon black. | ZHOU Jie YANG Yong-rong REN Xiao-hong STAPF Siegfried | 2006 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2006，7，8： | 10 |
| 2 | PE100管材料的聚集态结构和性能的固体NMR分析显示文摘PE100管材料基体树脂中界面区的含量比较高(高于10%),而完全无定形区的含量极低.界面区含量表征非晶区中运动部分受阻的链段所占的比重,因而上述结果意味着PE100管材料中非晶区中链段表现出强烈的缠结倾向.界面区的含量(或非晶区的组成特征)决定了材料的耐慢速裂纹增长性能,而固相区含量则决定了材料的力学强度,两种影响因素的平衡决定了最终管材料的长期使用性能. | 严小伟 历伟 任晓红 王靖岱 阳永荣 Siegfried Stapf Bernhard Blumich | 2008 | 材料研究学报2008，22，2： | 10 |
| 3 | Effects of termo-oxidative aging on chain mobility, phase com- position, and mechanical behavior of high-density poly- ethylene显示文摘 | Shi Xiaomei Wang Jingdai Stapf Siegfried | 2011 | Polymer Engineering and Science2011，51，11： | 1 |
| 4 | Dipolar NMR relaxation of adsorbates on surfaces of controlled wettability显示文摘In reservoir rocks,the term“ageing”refers to extended exposition to crude oil;a typically water-wet sandstone will then gradually become oil-wet as a consequence of the deposition of insoluble fractions of oil onto the surface grains.Rocks have been aged artificially by subjecting them to a bitumen solution at elevated temperature in order to achieve comparable surface properties for three different types of rock:Bentheimer,Berea Buff and Liege Chalk.Using saturated and aromatic model compounds as proxies for crude oil,the nuclear magnetic resonance(NMR)relaxation dispersion in native and aged rocks was compared and correlated to the properties of paramagnetic impurities in these rock types.Perfluorated liquids were found to follow the same trend as deuterated and naturally occurring oil components,suggesting they can be used as suitable tracers for wettability studies since the ^(19)F nucleus is absent in natural sources.By combining electron paramagnetic resonance(EPR)and dynamic nuclear polarization(DNP)it becomes possible to identify and quantify the origin of the dominating relaxation processes between native and aged rocks,providing an alternative approach to assess wettability in natural rocks. | Siegfried Stapf Igor Shikhov Christoph Arns Bulat Gizatullin Carlos Mattea | 2023 | Magnetic Resonance Letters2023，3，3： | 0 |
| 5 | Radicals on the silica surface:probes for studying dynamics by means of fast field cycling relaxometry and dynamic nuclear polarization显示文摘Determining the dynamics of adsorbed liquids on nanoporous materials is crucial for a detailed understanding of interactions and processes on the solid-liquid interface in many materials and porous systems.Knowledge of the influence of the presence of paramagnetic species on the surface or within the porous matrices is essential for fundamental studies and industrial processes such as catalysts.Magnetic resonance methods,such as electron paramagnetic resonance(EPR),nuclear magnetic resonance(NMR)and dynamic nuclear polarization(DNP),are powerful tools to address these questions and to quantify dy-namics,electron-nuclear interaction features and their relation to the physical-chemical parameters of the system.This paper presents an NMR study of the dynamics of polar and nonpolar adsorbed liquids,represented by water,n-decane,deuterated water and nonane-d20,on the native silica surface as well as silica modified with vanadyl porphyrins.The analysis of the frequency dependence of the nuclear spin-lattice relaxation time is carried out by separating the intra-and intermolecular contributions,which were analyzed using reorientations mediated by translational displacements(RMTD)and force-free-hard-sphere(FFHS)models,respectively. | Bulat Gizatullin Carlos Mattea Siegfried Stapf | 2023 | Magnetic Resonance Letters2023，3，3： | 0 |
| 6 | Editorial显示文摘Porous media are ubiquitous and characterized by a wide range of distinct morphological and topographical properties,often difficult to access by conventional methods.As a unique technology,magnetic resonance has been applied extensively for several decades to non-invasively characterize the structure,interactions and dynamics of fluids in porous media,as well as these media themselves.It does this via spectroscopy,relaxometry,diffusion,or imaging modalities.This special issue is dedicated to an editorial and a selection of outstanding talks/posters presented at the 15th International Bologna Conference Magnetic Resonance in Porous Media(MRPM15). | Ruiliang Bai Xueqian Kong Siegfried Stapf Wei Wang Fangrong Zong | 2023 | Magnetic Resonance Letters2023，3，2： | 0 |
| 7 | Binary fluids in mesoporous materials: Phase separation studied by NMR relaxation and diffusion显示文摘Relaxation and diffusion measurements were carried out on single and binary liquids filling the pore space of controlled porous glass Vycor with an average pore size of about 4 nm.The dispersion of the longitudinal relaxation time Tr is discussed as a means to identify liquid-surface interaction based on existing models developed for metal-free glass surfaces.In addition,the change of T1 and T2 with respect to their bulk values is discussed,in particular T2 serves as a probe for the strength of molecular interactions.As the native glass surface is polar and contains a large amount of hydroxyl groups,a pronounced interaction of polar and protic adsorbate liquids is expected;however,the T dispersion,and the corresponding reduction of T2,are also observed for non-polar liquids such as alkanes and cyclohexane.Deuterated liquids are employed for simplifying data analysis in binary systems,but also for separating the respective contributions of intra-and intermolecular interactions to the overall relaxation rate.Despite the lack of paramagnetic impurities in the glass material,H and 2H relaxation dispersions of equivalent molecules are frequently found to differ from each other,suggesting intermolecular relaxation mechanisms for the'H nuclei.The variation of the T dispersion when comparing single and binary systems gives clear evidence for the preferential adsorption of one of the two liquids,suggesting complete phase separation in several cases.Measurement of the apparent tortuosity by self-diffusion experiments supports the concept of a local variation of sample composition within the porespace. | Siegfried Stapf Niklas Siebert Timo Spalek Vincent Hartmann Bulat Gizatullin Carlos Mattea | 2023 | Magnetic Resonance Letters2023，3，2： | 0 |
| 8 | Phase Structures of Nascent Polyethylene Powder Studied by Wideline Proton NMR显示文摘聚乙烯粉末样品的 wideline 质子 NMR 系列从三个部件以贡献被分析:( 1 )有不动的链的僵硬部分,( 2 )与生产 Lorentzian 贡献到光谱的像液体的特性一起的一个软区域,并且( 3 )关于 CC 的甲又组的旋转在结合的 intermediateregion 部分被妨碍。相对集体部分以及链活动性在不同聚合技术生产的样品之中极大地变化了。NMR crystallinity 同意了很好,那由 WAXD 估计了并且比 DSC crystallinity 高得多,显示从水晶非结晶的分裂期间的贡献的包括。当采用聚合技术的一样的类型时,在僵硬部分的水晶的缺点能被处理参数显著地影响。在 NMR 系列的中间的区域高根据在 bimodal 之间的比较被分析密度聚乙烯和相应线性单峰的聚乙烯。NMR 分裂期间的集体部分能是在水晶的 lamellae 之间的领带分子的百分比的一个指示并且可以显著地因此影响聚合材料的机械性质,这被发现。 | 严小伟 王靖岱 任晓红 阳永荣 蒋斌波 VODA, Mihai Adrian BERTMER, Marko STAPF, Siegfried | 2007 | Chinese Journal of Chemistry2007，25，6： | 0 |
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