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We examine the relationship between board flexibility in diversity, experienced CEOs and corporate sustainability disclosure (CSD) in the developing economy context. We utilised the annual reports of all the listed commercial banks in Bangladesh between 2016 and 2020. Our study found a positive and significant association between board flexibility in diversity, which includes independent directors, foreign directors, directors with a business background, accounting professional directors, experienced CEOs and CSD. Importantly, the strategic leadership role of experienced CEOs constructs a good boardroom environment for the diversified board to place more emphasis on stakeholders’ interests and business legitimacy in a developing economy. However, we found a negative relationship between directors with a law background and CSD in the developing economy context, perhaps their role might be positive where a regulative environment exists for corporate sustainability disclosure. Our study was controlled by the audit committee and sustainability committee, and we found that the sustainability committee had a positive and significant association with CSD. Our findings have implications for developing economies specifically and around the globe in general.

A lightwell is a daylighting design that brings daylight (including sunlight and skylight) to the lower floors in a multi-storey building. A lightwell has a similar function to a lightpipe or an atrium, but its size is medium. This paper presents construction, measurement and RADIANCE simulation of a model lightwell. The model lightwell has a scale factor of 1:20 to simulate a real lightwell design for a multi-storey hotel. The model lightwell has the dimension of 100mm (width) x 150 mm (length) x 800 mm (height) contained in a six-storey model building section with a dimension of 400 mm x 500 mm x 800 mm. Comparison of the measured daylighting performance is made for two different inner surfaces (matt white paint and mirror-finish) of the model lightwell under overcast and sunny sky conditions, respectively. Computational analysis on the daylight factor (DF) or illuminance ratio provides essential information to determine key design parameters and applicability of a lightwell.

Abstract Background Parabolic Trough Solar Collector (PTSC) is one of the most popular and an effective device that converts solar radiation into a heat or useful energy. However, it suffers from high temperature gradient and low thermal efficiency. The solution for this problem is to use new advanced coolants (hybrid nanofluids) in order to enhance PTSC's thermal efficiency. Methods A numerical analysis on the thermo-hydraulic performance of a PTSC receiver's tube equipped with conical turbulators is presented. The Navier-Stokes equations are solved using Finite Volume Method (FVM) coupled with Monte Carlo Ray Tracing (MCRT) method. The flow and thermal characteristics as well as entropy generation of the PTSC's receiver tube are investigated for three hybrid nanofluids (Ag-SWCNT, Ag-MWCNT, and Ag-MgO) having a mixing ratio of (50:50) dispersed in Syltherm oil 800, Reynolds number (5000 to 100,000) and fluid inlet temperatures (400 to 650 K). Significant findings The conical turbulators effectively augmented the thermal performance by 233.4% utilising Ag-SWCNT/Syltherm oil instead of pure Syltherm oil. The performance evaluation criterion is found to be in the range of 0.9–1.82. The thermal and exergetic efficiencies increased by 11.5% and 18.2%, respectively. The maximum decrement in the entropy generation rate and entropy generation ratio are 42.7% and 33.7%.

The accuracy and reliability of a rapid blood alcohol estimation by means of a breath alcohol analyser has been evaluated under casualty department conditions in a series of 646 road-crash victims managed at the Dandenong and District Hospital. A higher correlation (r = 0.91) was found between the breath alcohol analyser readings in 633 casualties and those obtained by blood analysis in the police laboratory. In 13 unconscious casualties in whom a nasal breath test was performed, the correlation was lower (r = 0.76). In six casualties, the breath alcohol analyser readings showed lower alcohol concentrations than the legal limit of 0.05 g/100 mL (10.9 mmol/L), but blood analysis detected an illegal concentration. Further evaluation of the accuracy of the breath alcohol analyser in other casualty departments is necessary before it can be recommended as a screening device in States which have legislated for compulsory blood alcohol tests in adult road casualties.

The use of ionic liquid (IL) electrolytes promises to improve the energy density of electrochemical capacitors (ECs) by allowing for operation at higher voltages. Several studies have also shown that the pore size distribution of materials used to produce electrodes is an important factor in determining EC performance. In this research the capacitative, energy and power performance of ILs 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4), 1-ethyl-3-methylimidazolium dicyanamide (EMImN(CN)2), 1,2-dimethyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide (DMPImTFSI), and 1-butyl-3-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate (BMPyT(F5Et)PF3) were studied and compared with the commercially utilised organic electrolyte 1 M tetraethylammonium tetrafluoroborate solution in anhydrous propylene carbonate (Et4NBF4–PC 1 M). To assess the effect of pore size on IL performance, controlled porosity carbons were produced from phenolic resins activated in CO2. The carbon samples were characterised by nitrogen adsorption–desorption at 77 K and the relevant electrochemical behaviour was characterised by cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy. The best capacitance performance was obtained for the activated carbon xerogel with average pore diameter 3.5 nm, whereas the optimum rate performance was obtained for the activated carbon xerogel with average pore diameter 6 nm. When combined in an EC with IL electrolyte EMImBF4 a specific capacitance of 210 F g−1 was obtained for activated carbon sample with average pore diameter 3.5 nm at an operating voltage of 3 V. The activated carbon sample with average pore diameter 6 nm allowed for maximum capacitance retention of approximately 70% at 64 mA cm−2.

The dynamic nature of coral reefs offers a rare opportunity to examine the response of ecosystems to disruption due to climate change. In 1998, the Great Barrier Reef experienced widespread coral bleaching and mortality. As a result, cryptobenthic fish assemblages underwent a dramatic phase-shift. Thirteen years, and up to 96 fish generations later, the cryptobenthic fish assemblage has not returned to its pre-bleach configuration. This is despite coral abundances returning to, or exceeding, pre-bleach values. The post-bleach fish assemblage exhibits no evidence of recovery. If these short-lived fish species are a model for their longer-lived counterparts, they suggest that (1) the full effects of the 1998 bleaching event on long-lived fish populations have yet to be seen, (2) it may take decades, or more, before recovery or regeneration of these long-lived species will begin, and (3) fish assemblages may not recover to their previous composition despite the return of corals.

Abstract Besides the apparent need to reduce greenhouse gas emissions, other important factors contributing to the renewed interest in biofuels are energy security concerns and the need of sustainable transportation fuel. Nearly 30% of the annual CO2 emissions in the U.S. come from the transportation sector and more than half of the fuel is imported. Biofuels appear to be a promising option to reduce carbon dioxide emissions, and the reliance on imported oil concomitantly. The interest on (ligno) cellulosic ethanol is gaining momentum as corn-based ethanol is criticized for using agricultural outputs for fuel production. Among many lignocellulosic feedstocks, woodchips is viewed as one of the most promising feedstocks for producing liquid transportation fuels. The renewable and carbon neutral nature of the feedstocks, similar chemical and physical properties to gasoline, and the low infrastructure cost due to the availability of fuel flex vehicles and transportation networks make (ligno) cellulosic bioethanol an attractive option. An in-depth LCA of woodchips shows that harvesting and woodchips processing stage and transportation to the facility stage emit large amount of environmental pollutants compared to other life cycle stages of ethanol production. Our analysis also found that fossil fuel consumption and respiratory inorganic effects are the two most critical environmental impact categories in woodchips production. We have used Eco-indicator 99 based cradle-to-gate LCA method with a functional unit of 4 m3 of dry hardwood chips production.

Abstract This review article aims to provide a comprehensive understanding of radiative cooling technology and their applications, especially on the integration of radiative coolers with devices. Over the past decades, radiative coolers and their applications have been intensively investigated because of their outstanding features for energy saving. The fundamental mechanism and characteristics of radiative cooling, in particular, atmospheric influences, and photothermal manipulation through structural and materials engineering, play essential roles in most of the practical applications. In general, these main factors concomitantly influence the cooling performance of a radiative cooler. However, comprehensive review investigating these main parameters simultaneously remains elusive. In this article, the fundamental features of radiative coolers are discussed, especially the influences of atmospheric conditions at different locations on the radiative coolers, and the photothermal manipulation capability and cooling performance of different types of radiative coolers. The applications, challenges faced in this field and the future trends are also discussed. This article will provide guidance towards integration of radiative coolers with functional devices for both academic researchers and engineers in the fields of energy harvesting, fluidic cooling, energy efficient clothing, and architecture.

Abstract A low cost graphite was examined as a negative electrode for rechargeable lithium batteries. The use of an electrolyte solution consisting of LiPF6 (1 mol dm−3) in ethylene carbonate (EC) and dimethyl carbonate (DMC) at a volume ratio of 2:1 resulted in a capacity loss of 35% on the first cycle. When small quantities of dimethyl pyrocarbonate (DMPC) were added to the binary electrolyte system, the capacity loss on the first cycle was only 18% and thereafter a practical capacity value of 357 mA h g−1 was sustained for more than 50 cycles, representing more than 2000 h of cycling.