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The application of thermoelectric generator (TEG) systems in waste heat recovery has attracted more and more attention. In this work, the effect of interfacial heat transfer on the performance of TEG module was experimentally and numerically investigated. Three kinds of thermal greases with thermal conductivities of 2.0, 2.5, and 3.0 W/(m∙K) were used as thermal interface materials (TIMs) to improve interfacial heat transfer at different external pressures ranging from 0.1 to 0.4 MPa. The open-circuit voltage, output power, and thermal interfacial resistance were measured at different experimental conditions. It was found that the performance of the TEG module can be greatly improved by using thermal greases as TIMs. The open-circuit voltages increased from 1.73 to either 3.07, 3.4, or 3.57 V with k = 2.0, 2.5, and 3.0 W/(m∙K) thermal greases respectively used as TIMs when the temperature difference was 60 °C and external pressure was 0.1 MPa. However, the performance of the TEG was slightly affected by external pressure when thermal greases used as TIMs. The open-circuit voltages were 3.07, 3.13, 3.17, and 3.20 V at external pressures of 0.1, 0.2, 0.3, and 0.4 MPa when the temperature difference ΔT = 60 °C and k = 2.0 W/(m∙K) thermal greases were used as TIMs.

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The existing literature does not provide adequate insight into the initial diffusion of new management practices, especially those that yield no immediate economic benefits, and have not yet gained legitimacy. We study how firms' local institutional environments influence early adoption behavior, examining the spread of corporate social responsibility (CSR) reports in China's banking industry from 2006 to 2011. We find that banks are more likely to be first movers of CSR reporting if they operate in communities where more companies publish CSR reports or where there are guidelines encouraging CSR reporting, and the impacts of these two institutional factors are further moderated by the length of time that banks have operated in communities. Our study highlights the usefulness of institutional theory in understanding the initial adoption of new management practices, when the organizational field is defined as a geographic community instead of an industry sector and its supply chain.

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The advent of nanotechnology has made it possible to engineer sophisticated chiral platforms at the nanoscale. Importantly, such sample preparations require complex nanofabrication processes due to the 3D nature of chiral materials. Over the past two decades, various approaches have been implemented including fabrication of nanohelices and layer-by-layer deposition of chiral materials. [6,[17][18][19][20][21][22] More sophisticated approaches for producing 3D chiral nanomaterials use focused ion beam and grazing-incidence deposition. [23,24] Using all these techniques, a tremendous progress has been achieved both in terms of the materials and of the spiral arrangements for the fabrication of 3D nanohelices operating at the visible and near-infrared (NIR) frequencies. [25] 2D fabrication, on the other hand, represents a more facile sample preparation method since materials can be simply fabricated in a single step, e.g., after lithographic patterning of the substrate. [26][27][28] However, strictly 2D objects with rotational symmetry in the absence of losses do not possess chiral properties because the sense of twist is reversed when light propagation is reversed. [29,30] This leads to a reduced chiral response for planar plasmonic samples and metamaterials. Indeed, the experimental observation of spin-dependent optical effects for right circularly polarized (RCP) and left circularly polarized (LCP) light in planar plasmonic samples have been attributed to such effects as the presence of the substrate and off-normal illumination conditions. [26,31,32] Fundamentally, the diminished 2D chiral response is intimately related to the reciprocity of the optical process. Thus, chiral response in a planar structure can also be observed if the reciprocity is broken, e.g., by introduction of losses. [30,33] Another approach of using planar fabrication technology for observation of chiral optical response at the nanoscale is through nanopatterning and subsequent etching of purely dielectric nanostructures. [32,34] The resulting nanostructures are inherently 3D and support various Mie-type optical modes, the interplay of which can exhibit chiral character. Compared to the plasmonic systems, the typical disadvantages of using purely dielectric structures include relatively larger size, modest field enhancement, and field localization values.Here, we propose an alternative approach to enhance the chiral optical effects in planar plasmonic systems by coupling them to photonic modes of a dielectric waveguide. The hybrid modes of the resulting plasmonic-photonic metasurface exhibit Plasmonic nanosystems and metamaterials have recently attracted considerable attention because of their ability to enhance the light-matter interactions. One of such optical phenomena is the chiral-or handedness-dependent response which typically requires 3D samples. Planar structures that can exhibit chiral response are highly desirable because of their facile fabrication, however fundamental challenges arising from the 2D nature of these systems preven...