We attempt to provide a more nuanced view of the relationship between corporate social responsibility (CSR) and firm financial performance using a competitive-action perspective. We argue that ...competitive action should be considered as an important contingency that determines the effects of CSR activities on firm financial performance. Using data for 113 publicly listed U.S. firms in the software industry between 2000 and 2005, we found that socially responsible activities (positive CSR) enhance firm financial performance when the firm’s competitive-action level is high, whereas socially irresponsible activities (negative CSR) actually improve firm financial performance when the competitive-action level is low. By introducing competitive action as an important contingency, this study contributes to the literature on CSR and strategic management.
Na‐ion batteries are an attractive alternative to Li‐ion batteries for large‐scale energy storage systems because of their low cost and the abundant Na resources. This Review provides a comprehensive ...overview of selected anode materials with high reversible capacities that can increase the energy density of Na‐ion batteries. Moreover, we discuss the reaction and failure mechanisms of those anode materials with a view to suggesting promising strategies for improving their electrochemical performance.
Anode materials with high reversible capacities that can increase the energy density of Na‐ion batteries are the focus of this Minireview. Moreover, the reaction and failure mechanisms of those anode materials are discussed with the aim of targeting promising strategies for improving their electrochemical performance.
In future biorefineries, the development of inexpensive and renewable reagents is highly desirable. In this work, we report a renewable and new class of deep eutectic solvent (DES) synthesized from ...lignin-derived phenolic compounds. Novel DESs tested in this work showed their potential as solvents for biomass pretreatment in terms of lignin removal and sugar release after enzymatic saccharification. The recycling and reusability of DESs were also evaluated. The results from this study prove that DESs synthesized from renewable resources are promising solvents for future biorefineries.
This paper proposes a coarse-fine dual-loop architecture for the digital low drop-out (LDO) regulators with fast transient response and more than 200-mA load capacity. In the proposed scheme, the ...output voltage is coregulated by two loops, namely, the coarse loop and the fine loop. The coarse loop adopts a fast current-mirror flash analog to digital converter and supplies high output current to enhance the transient performance, while the fine loop delivers low output current and helps reduce the voltage ripples and improve the regulation accuracies. Besides, a digital controller is implemented to prevent contentions between the two loops. Fabricated in a 28-nm Samsung CMOS process, the proposed digital LDO achieves maximum load up to 200 mA when the input and the output voltages are 1.1 and 0.9 V, respectively, with a chip area of 0.021 mm 2 . The measured output voltage drop of around 120 mV is observed for a load step of 180 mA.
Despite intensive research on photochemical activation of sol–gel metal oxide materials, the relatively long processing time and lack of deep understanding of the underlying chemical courses have ...limited their broader impact on diverse materials and applications such as thin‐film electronics, photovoltaics, and catalysts. Here, in‐depth studies on the rapid photochemical activation of diverse sol–gel oxide films using various spectroscopic and electrical investigations for the underlying physicochemical mechanism are reported. Based on the exhaustive chemical and physical analysis, it is noted that deep ultraviolet‐promoted rapid film formation such as densification, polycondensation, and impurity decomposition is possible within 5 min via in situ radical‐mediated reactions. Finally, the rapid fabrication of all‐solution metal oxide thin‐film‐transistor circuitry, which exhibits stable and reliable electrical performance with a mobility of >12 cm2 V−1 s−1 and an oscillation frequency of >650 kHz in 7‐stage ring oscillator even after bending at a radius of <1 mm is demonstrated.
The general physicochemical mechanisms underlying photoactivated sol–gel reactions are described, with comprehensive chemical and structural analysis inducing rapid (<5 min) fabrication of various metal oxide films at low temperatures (<150 °C), and all‐solution processed high‐performance electronic devices and circuitry on ultrathin polymeric substrates are demonstrated. This will open new possibilities to prepare future electronic materials in a fast, scalable, and economic manner.
Light in biological media is known as freely diffusing because interference is negligible. Here, we show Anderson light localization in quasi-two-dimensional protein nanostructures produced by ...silkworms (Bombyx mori). For transmission channels in native silk, the light flux is governed by a few localized modes. Relative spatial fluctuations in transmission quantities are proximal to the Anderson regime. The sizes of passive cavities (smaller than a single fibre) and the statistics of modes (decomposed from excitation at the gain-loss equilibrium) differentiate silk from other diffusive structures sharing microscopic morphological similarity. Because the strong reflectivity from Anderson localization is combined with the high emissivity of the biomolecules in infra-red radiation, silk radiates heat more than it absorbs for passive cooling. This collective evidence explains how a silkworm designs a nanoarchitectured optical window of resonant tunnelling in the physically closed structures, while suppressing most of transmission in the visible spectrum and emitting thermal radiation.
We report on the catalytic pyrolysis of switchgrass and its three main components (cellulose, hemicellulose and lignin) over H-ZSM5 catalyst. The yields of aromatic hydrocarbons for the three ...components decreased in the following order: cellulose > hemicellulose >> lignin. Moderately higher temperature favored formation of aromatics. The results indicate that H-ZSM5 catalyst did not remove oxygen in an optimal pathway for catalytic pyrolysis of biomass. Dehydration was the dominant oxygen removal mechanism for catalytic pyrolysis, while decarbonylation to CO was favored over decarboxylation to CO sub(2). This suggests that higher yields of aromatics might be achieved by catalyst improvements or reactor design that optimizes deoxygenation pathway. For cellulose and hemicellulose, coke produced catalytically contributed a larger fraction of solid carbonaceous residue than char from purely thermal processes. In the case of lignin, thermal rather than catalytic processes primarily contribute to the production of solid carbonaceous residue. Product distribution from catalytic pyrolysis of switchgrass appeared to be the additive contribution of the three individual components, which indicates that there was no significant interaction among the biomass-derived products.
The issues over increases in energy demand and environmental pollution attributed to excessive use of fossil fuel have been the driving forces of the exploration for eco-friendly resource. ...Lignocellulosic biomass consisting of carbohydrates and lignin can be a renewable feedstock for replacing fossil fuels in the future because it is a plentiful and carbon neutral material. Especially, lignin, cross-linked phenolic polymers, is a topic of interest owing to its abundant production from pulp/paper industries as well as lignocellulose based biorefinery. The large potential of platform chemicals and biofuels from lignin has opened up an extensive range of opportunities to develop thermal and catalytic conversion technology. Over a few decades, several lignin conversion processes including catalytic pyrolysis, catalytic depolymerization, and catalytic oxidation have been developed to improve target products yields and to suppress side reactions. More recently, lignin-first approaches which maintain carbohydrates intact by selective extraction of lignin as valuable phenolics from whole biomass has been suggested. This review introduces recent ten years progress on thermal and catalytic conversion technology in terms of process type, catalyst development, and target products. This review is expected to offer an influential information for future research into the thermal and catalytic conversion of lignin as well as lignocellulosic feedstock.
•Recent discoveries in thermal and catalytic lignin conversion are introduced.•A proper conversion process should be considered depending on the lignin type.•Catalyst plays a decisive role in product distribution and selectivity in process.•The challenges and future perspective of each process is discussed.
A harmonized three-component composite system which preserves the characteristics of individual components is of interest in the field of energy storage. Here, we present a graphene-encapsulated ...MXene Ti2CTx@polyaniline composite (GMP) material realized in a systematically stable configuration with different ternary nanomaterials for supercapacitor electrodes. Due to the different zeta potentials in a high-pH solution, chemically converted graphene (negatively charged) is thoroughly unfolded to allow full encapsulation, but the MXene Ti2CTx@polyaniline composite with a low positive zeta potential is easily attracted toward a counter-charged substance. The obtained GMP electrode exhibits improved cycle stability and better electrochemical performance owing to the use of mechanically robust and chemically inert graphene and the densely intercalated conductive polyaniline between the multi-layer MXenes. The GMP electrode has a high gravimetric capacitance of 635 F g-1 (volumetric capacitance of 1143 F cm-3) at a current density of 1 A g-1 with excellent cycling stability of 97.54% after 10,000 cycles. Furthermore, the asymmetric pouch-type supercapacitor assembled using the GMP as a positive electrode and graphene as a negative electrode yields a high energy density of 42.3 Wh kg-1 at a power density of 950 W kg-1 and remarkable cycle stability (94.25% after 10,000 cycles at 10 A g-1).
PDF
