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The second‐law analysis evaluates the irreversibilities of a process. Systematic study of the relationship between thermodynamic efficiency and process modifications enhances process synthesis. The Allam cycle is an oxy‐fuel combustion cycle with nearly complete carbon capture that offers greater efficiency than current electricity generating systems. This study applies lost work analysis to the original Allam cycle and three modifications to obtain the distribution of irreversibilities and the effects of different configurations among potential process improvements for more sustainable power generation. The major inefficiencies are from the combustors and heat exchangers. We also examine the economic profitability of the alternatives. The largest equipment costs are for the turbines, compressors, and recuperators. We find that improving efficiency leads to less economic return; a configuration with partial compression has the highest efficiency, while the original Allam cycle has the highest profitability. We discuss how to resolve this apparent conflict between sustainability and profitability. [ABSTRACT FROM AUTHOR]

Aim: To investigate the possible covariation of grey matter volume (GMV) and white matter fractional anisotropy in infants with spastic cerebral palsy (CP) and periventricular white matter injury. Method: Thirty‐nine infants with spastic CP and 25 typically developing controls underwent structural magnetic resonance imaging and diffusion tensor imaging. Multimodal canonical correlation analysis with joint independent component analysis were used to capture differences in GMV and fractional anisotropy between groups. Correlation analysis was performed between imaging findings and clinical features. Results: Infants with spastic CP showed one joint group‐discriminating component (i.e. GMV‐fractional anisotropy) associated with regions in the cortico‐basal ganglia‐thalamo‐cortical loop and in the corpus callosum compared to typically developing controls and one modality‐specific group‐discriminating component (i.e. GMV). Significant negative correlations were found between loadings in certain regions and the motor function score in spastic CP. Interpretation: In infants with spastic CP, covarying GMV‐fractional anisotropy and altered GMV in specific regions were implicated in motor dysfunction, which confirmed that simultaneous GMV and fractional anisotropy changes underly motor deficits, but might also extend to sensory, cognitive, or visual dysfunction. These findings also suggest that multimodal fusion analysis allows for a more comprehensive understanding of the relevance between grey and white matter structures and its crucial role in the neuropathological mechanisms of spastic CP. [ABSTRACT FROM AUTHOR]

In the work, new type composites of acrylonitrile butadiene rubber (NBR) and polyurethane-sericite (PU-sericites) hybrid materials was prepared by melt blending method. The PU-sericite hybrid phase was formed via the reaction of NCO groups of NCO terminated PU prepolymer and OH groups of sericites. It was indicated by dynamical mechanical analysis that the damping property of NBR decreases as the amount of PU increases, whereas the mechanical properties at low temperature are enhanced. When PU of 10 wt% was added in, a better damping property can be obtained. The damping property of NBR/PU composites would decrease when adding in sericites, however, the mechanical properties at low temperature would be improved. With PU-sericites hybrid added, the compatibility between sericites and NBR/PU composites would be enhanced and the quasi-interpenetrating polymer network structures would be formed, resulting in a better mechanical property of NBR/(PU-sericites) composites. [ABSTRACT FROM AUTHOR]

In this paper, graphene oxide (GO) was prepared by modified Hammer's method using graphite, which was then modified with silane coupling agent (MGO). With two-roll mill mixing method, GO was used as filler and composites like nitrile-butadiene rubber (NBR)/GO(MGO) composites and nitrile-butadiene rubber (NBR)/ 2,2'-methylenebis(6-tert-butyl-4-methyl-phenol) (AO-2246)/ GO(MGO) composites were prepared. Fourier Transform Infrared Spectrometer (FT-IR), Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM) were used to observe and study the molecular structure and morphology of GO, MGO and the composites. Dynamic Mechanical Analyzer (DMA) was used to study the damping properties of the composites. The composites reinforced by GO and MGO exhibited better damping and mechanical property. The damping property of NBR/GO composites weakens but the damping property of NBR/AO-2246/GO composites enhances with increase graphene oxide (GO). The damping property of the composites is enhanced by the addition of MGO. The main reason of the excellent properties of the graphene derivatives is its structural characteristics and the associated hydrogen bonds in the structure. [ABSTRACT FROM AUTHOR]

Graphene has been considered an ideal nanoscale reinforced phase for preparing high-performance composites, but the poor compatibility and weak interfacial interaction with the matrix have limited its application. Here a highly effective and environmentally friendly method for the functionalization of graphene is proposed through an interaction between as-exfoliated graphene and (3-aminopropyl) triethoxysilane (KH550), in which 1-butylsulfonate-3-methylimidazolium bisulfate (BSO3HMIm)(HSO4) ionic-liquids-modified graphene was prepared via an electrochemical exfoliation of graphite in (BSO3HMIm)(HSO4) solution, then (BSO3HMIm)(HSO4)-modified graphene as a precursor was reacted with amine groups of KH550 for obtaining (BSO3HMIm)(HSO4)/KH550-functionalized graphene. The final products as filler into carboxylated acrylonitrile‒butadiene rubber (XNBR) improve the dynamic mechanical properties. The improvement in the dynamic mechanical properties of the nanocomposite mainly depends on high interfacial interaction and graphene's performance characteristics, as well as a good dispersion between functionalized graphene and the XNBR matrix. [ABSTRACT FROM AUTHOR]

Organic hybrid damping materials have achieved sustainable development in recent years for superior damping properties due to the hydrogen bonding of hindered phenol. However, the aggregation and crystallization of hindered phenol in the matrix can lead to a sharp decline in material properties. Thus, a series of hindered phenol hybrid carboxylated nitrile rubber (XNBR) composites with different types and contents of hindered phenol were prepared by melt blending to study the effects of different hindered phenol on the properties of organic hybrid damping materials. A dynamic mechanical analyzer (DMA) and scanning electron microscope (SEM) were used to study the dynamic mechanical properties and cross-section morphology of composites. X-ray diffraction (XRD) was used to study the crystallization of hindered phenol. The results show that the properties of organic hybrid damping materials were affected by the structure of hindered phenol, and that hindered phenol molecules with a linear structure had better performances. The greater the number of hydrogen bonds between hindered phenol and the XNBR matrix, the more difficult it was for the hindered phenol to crystallize. [ABSTRACT FROM AUTHOR]

Back Ground: Subjective cognitive decline (SCD) may be the first clinical sign of Alzheimer's disease (AD). The possible neural mechanisms of SCD are not well known. This study aimed to compare percent amplitude of fluctuation (PerAF) and structural covariance patterns in patients with SCD and healthy controls (HCs)., Methods: We enrolled 53 patients with SCD and 65 HCs. Resting-state functional magnetic resonance imaging (MRI) data and T1-weighted anatomical brain 3.0-T MRI scans were collected. The PerAF approach was applied to distinguish altered brain functions between the two groups. A whole-brain voxel-based morphometry analysis was performed, and all significant regions were selected as regions of interest (ROIs) for the structural covariance analysis. Statistical analysis was performed using two-sample t -tests, and multiple regressions were applied to examine the relationships between neuroimaging findings and clinical symptoms., Results: Functional MRI results revealed significantly increased PerAF including the right hippocampus (HIPP) and right thalamus (THA) in patients with SCD relative to HCs. Gray matter volume (GMV) results demonstrated decreased GMV in the bilateral ventrolateral prefrontal cortex (vlPFC) and right insula in patients with SCD relative to HCs. Taking these three areas including the bilateral vlPFC and right insula as ROIs, differences were observed in the structural covariance of the ROIs with several regions between the two groups. Additionally, significant correlations were observed between neuroimaging findings and clinical symptoms., Conclusion: Our study investigated the abnormal PerAF and structural covariance patterns in patients with SCD, which might provide new insights into the pathological mechanisms of SCD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Xu, Wei, Zhang, Zhao, Geng, Mai, Li, Liang, Chen, Zeng, Deng and Liu.)

To improve the dispersion of talcum powder (Talc) for polymer applications, modified nano-titania powders (TiO 2 ) using a silane coupling agent (KH550), a titanate coupling agent (NDZ201) and sodium polyacrylate (PAAS) were well adhered to the surface of Talc with a ball milling method, thereby preparing a series of mixed Talc@TiO 2 particles to realize good dispersion in carboxylated acrylonitrile-butadiene rubber (XNBR). Note that Talc@TiO 2 particles modified by PAAS and NDZ201 show better colloidal dispersion in anhydrous ethanol due to organification and repulsion of charge, with original Talc and NDZ201 modified Talc@TiO 2 powders as a comparison. Modified Talc@TiO 2 hybrid XNBR shows good performance characteristics, including damping capacity and impact resistance, depending mainly on the excellent mechanical property of Talc, good dispersion and the high adhesive force between modified Talc@TiO 2 and XNBR., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)