438 research outputs found
Mindfulness in Ethical Consumption: The Mediating Roles of Connectedness to Nature and Self-control
Get PDFPurpose
Ethical consumption is an integral component for the sustainable development in the world and is especially challenging in the Western consumer society. This research demonstrates that mindfulness, a Buddhism-based notion, is associated with two related and distinctive approaches of ethical consumption: refinement and reduction. It examines the psychological mechanisms underlying the effects of mindfulness on these two approaches of ethical consumption.
Design/methodology/approach
Self-report data were collected through an online survey with consumers from western societies (N = 523).
Findings
The findings show (1) that the significance of mindfulness on both approaches of ethical consumption and (2) that the contrast between the different mechanisms underlying them. Specifically, the mindfulness–consumption refinement link is fully mediated by connectedness-to-nature whereas the mindfulness–consumption reduction link is fully mediated by connectedness-to-nature and self-control. A series of supplementary studies further confirmed the proposed model.
Research limitations/implications
It demonstrates the multifaceted and complex nature of ethical consumption, which is positively associated with mindfulness but through distinctive psychological mechanisms.
Practical implications
The multifaceted and complex nature of ethical consumption and its underlying drivers need special attention. Mindfulness can be an effective means to boost ethical consumption behavior. Meanwhile, nurturing the sense of connectedness to nature and self-control capability facilitates the path-through of the positive impacts of mindfulness
Social implications
The findings can be adopted to enhance the effectiveness of mindfulness practice in promoting ethical consumption towards achieving the Sustainable Consumption goal, especially in the West.
Originality/value
The paper makes original contribution by conceptualizing two interrelated and distinctive approaches of ethical consumption and shows how mindfulness promotes both through different mediating pathways. Overall, this study paints a clearer picture how mindfulness relates to ethical consumption.This research is supported by a Strategic Research Grant of City University of Hong Kong (CityU 7004789) awarded to the corresponding author Stella Yiyan Li and a Strategic Research Grant of
City University of Hong Kong (CityU 7004571) awarded to the second author Dr Liyuan Wei
A review on mathematical modelling of direct internal reforming- solid oxide fuel cells
No full textThe Solid Oxide Fuel Cells (SOFCs) anode materials are catalytically active for Direct Internal Reforming (DIR) thus avoiding the need of external reformer. However, practical application of DIR in SOFCs requires careful system design and selection of operating conditions to avoid cell degradation due to carbon depositions and other impurities. In recent years, numerous simulation studies, besides experimental investigations, have been carried out to understand the physical and electrochemical complexities of DIR-based SOFC systems in order to develop viable designs and optimize the operating conditions before conducting costly experiments. The objective of this work is to review the present status of DIR-SOFC modeling efforts and consolidate their findings in order to highlight the unresolved problems for future research in this field. A specific focus of this review has been given to the multiscale mathematical modeling. Pre-reforming techniques, influences of the chemical and electrochemical reaction kinetics and operational variables along with future prospects of the DIR-SOFC have been also reviewed and discussed
Computational fluid dynamics modeling of anode-supported solid oxide fuel cells using triple-phase boundary-based kinetics
No full textFuel oxidation in the solid oxide fuel cell occurs at the triple-phase boundary where electronic, ionic, and gas phases simultaneously interact. A quantitative knowledge of the triple-phase boundary density is therefore important in analyzing the fuel cell performance as well as designing the electrode structures and materials. In this work, the triple-phase boundary-based kinetics, developed from the patterned anode experiments are used in a computational fluid dynamics model to assess the performance of anode-supported nickel-yttria stabilized zirconia cells. The simulation results suggested that the effective triple-phase boundary density required to carry out the electrochemical oxidation reactions is several orders of magnitude lower when compared with the physical triple-phase boundary density of similar cermet anodes. The anode concentration gradients are found to be larger near the anode/electrolyte interface compared to that of fuel channel that is ascribed to the electrochemical reactions taking place in the anode active region and mass transport resistance of the microporous structure. The cell voltage decreased rapidly at high current density due to fuel starvation and subsequent drop of the exchange-current density. Furthermore, the effects of triple-phase boundary density and operating temperature on the cell performance are also studied and discussed
Zwitterionic sulfhydryl Sulfobetaine stabilized platinum nanoparticles for ernhanced Dopamine detection and antitumor ability
No full textHerein, three kinds of molecules were used to modify the surface of platinum nanoparticles (Pt NPs) to tune their surface charge. Zwitterionic thiol-functionalized sulfobetaine (SH-SB) stabilized Pt NPs (SH-SB/Pt NPs) had the highest oxidase activity and peroxidase activity in the prepared platinum nanozymes due to the generation of reactive oxygen species. In addition, a colorimetric dopamine detection method was established based on the peroxidase activity of SH-SB/Pt NPs. This method had a wide range (0-120 μM), a low detection limit (0.244 μM), and high specificity. More importantly, SH-SB/Pt NPs displayed little hemolysis and good stability in the presence of proteins. SH-SB/Pt NPs demonstrated high cytotoxicity in vitro and good antitumor ability in vivo, which was attributed to the photothermal conversion ability of SH-SB/Pt NPs and the generation of reactive oxygen species in the acidic environment. The surface modification of nanozymes using zwitterionic molecules opens a new method to improve the catalytic activity and antitumor ability of nanozymes. </p
Ore Geology, Fluid Inclusion Microthermometry and H-O-S Isotopes of the Liyuan Gold Deposit, Central Taihang Mountains, North China Craton
No full textThe Liyuan gold deposit, located in the central Taihang Mountains, North China Craton, forms an important part of the Taihang polymetallogenic belt. The origin of ore-forming fluids and the genesis of this deposit remains controversial. In this paper, fluid inclusions (FIs) microthermometry and H-O-S isotopes analysis are conducted to constrain the origin of ore-forming fluids and genesis. The main findings are as follows: (1) Three hydrothermal metallogenic stages are identified: Quartz–pyrite, quartz–polymetallic sulfide, and quartz–carbonate stages; (2) three types of primary FIs are recognized: CO2-aqueous (type I), pure CO2 (type II), and aqueous FIs (type III); (3) ore-forming fluids are characterized by medium–low temperatures, medium–low salinity, and H2O-CO2-NaCl ± CH4 system; (4) H-O isotopes indicate that the ore-forming fluids mainly have a magmatic origin and late-stage ore fluids mixed with meteoric water; (5) S isotopes further confirm that the sulfides most likely have a deep magma source with variation caused by changes in oxygen fugacity; and (6) fluid immiscibility and water–rock interactions are considered to be the two main mechanisms of gold deposition. Due to the lack of large granite bodies exposed in this ore district, we infer that the fluids of gold deposit and quartz porphyry may have both been exsolved from a concealed granite pluton at deeper locations, and we further propose that Liyuan gold deposit is typical magmatic–hydrothermal gold deposits
Methane Steam Reforming Kinetics in Operating Solid Oxide Fuel Cells
No full textBy 2040, electricity generation will account for more than 40 % of global energy consumption. Gains in efficiency through energy-saving practices and technologies – such as hybrid vehicles and new, high efficiency natural gas power plants – will temper demand growth and curb emissions. Different from the conventional thermal power plants, fuel cells are potentially more efficient than traditional heat engines since they are not limited by the maximum efficiency of the Carnot cycle. Rather, the efficiency of the fuel cell based power plant can be increased to about 70% when coupled with a gas turbine. However, the development of Solid-Oxide Fuel Cells (SOFC) is still facing a lot of challenges and a better understanding of the underlying internal steam reforming reaction is needed. To do this, a number of mathematical frameworks have been proposed in the last two decades to model the planar, the integrated planar, the tubular and the monolithic designs of the SOFCs. Mathematical models of the SOFCs are important tools in understanding and evaluating the effects of various fuels and operation parameters on SOFC performance. They are used by fuel cell scientists and developers to elucidate the processes within the cells and to optimize design factors of the cell such as materials. This work focuses on modelling of SOFC with Ni ? Y SZ anode and Ni ? GDC anode. To do this, the readily available Cycle-Tempo is used. Calculations of factors such as from Cycle-Tempo are compared with the simulated results from CFD generated from the FLUENT software. The calculated cell performance for SOFCs is strongly influenced by the kinetic parameter of the internal steam reforming reaction. Due to the lack of sufficient kinetic parameters for the SOFC of interest, experimental studies are conducted to find the methane steam reforming kinetic parameters which are subsequently applied to the simulation.Process and EnergyMechanical, Maritime and Materials Engineerin
Numerical study on aerodynamic noise performances of axial spacing in a contra-rotating axial fan
Get PDFIn order to study the effect of axial spacing on behaviors of aerodynamic performance and aerodynamic noises in a contra-rotating fan, the steady/unsteady Reynolds-averaged Navier-Stokes equations are solved by the numerical method in conjunction with a SST turbulence model, and the effects of axial spacing on performance and aerodynamic characteristics are investigated. Furthermore, BEM is adopted to compute the radiation noise of the contra-rotating fan caused by unsteady pressure fluctuations. The results show that axial spacing is an important factor which can affect the aerodynamic performance of contra-rotating fan. As a whole, the effect of axial spacing on the blade loading of Rotor 2 is significantly greater than that of Rotor 1. For Rotor 2, the smaller axial spacing leads to the large secondary flow loss, and the larger axial spacing leads to the strong mixing loss. With the increase of axial spacing, the radiation noise at the characteristic frequency decreases, but showed different changing degrees. With consideration of the aerodynamic performance and aerodynamic noises of the contra-rotating fan, the optimal comprehensive performance appears at the axial spacing of 0.5 chord
Numerical simulation of unsteady aerodynamic interactions of contra-rotating axial fan.
No full textThis paper describes the investigations performed to better understand unsteady effect that develop in a contra-rotating axial fan. More specifically, this study focuses on rotor-rotor interactions effects on unsteady characteristic and blade aerodynamic force. The investigation method is based on three-dimensional URANS simulations, in conjunction with SST turbulence model. At first, the experimental measurements are compared to evaluate ability of the numerical method in estimation of unsteady flows. The results show that rotor-rotor interaction in the contra-rotating fan played an important role in aerodynamic efficiency. Unsteady effect increased flow losses of rotor 1, but effectively inhibited flow losses of rotor 2. The inhibition effect was mainly caused by wake recovery effect of upstream wakes in the flow passage of rotor 2. Meanwhile, negative jet flow enhanced boundary layer energy of the blade of rotor 2, so that flow separation was postponed. Different configurations consider five sets of axial spacing dimensions. Specific survey of flows under the same operation conditions indicates that axial spacing is responsible for the unsteady interaction effect. The blade aerodynamics analysis shows that the influence of the downstream potential flow disturbance on rotor 1 is greater than the effect of the upstream wake on rotor 2
- …
