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Toward green production practices: empirical evidence from Thai manufacturers' technical efficiency
No full textPurpose: The development of green manufacturing has become essential to achieve sustainable development and modernize the nation’s manufacturing and production capacity without increasing nonrenewable resource consumption and pollution. This study investigates the effect of green industrial practices on technical efficiency for Thai manufacturers. Design/methodology/approach: The study uses stochastic frontier analysis (SFA) to estimate the stochastic frontier production function (SFPF) and inefficiency effects model, as pioneered by Battese and Coelli (1995). Findings: This study shows that, on average, Thai manufacturing firms have experienced declining returns-to-scale production and relatively low technical efficiency. However, it is estimated that Thai manufacturing firms with a green commitment obtained the highest technical efficiency, followed by those with green activity, green systems and green culture levels, compared to those without any commitment to green manufacturing practices. Finally, internationalization and skill development can significantly improve technical efficiency. Practical implications: Green industry policy mixes will be vital for driving structural reforms toward a more environmentally friendly and sustainable economic system. Furthermore, circular economy processes can promote firms' production efficiency and resource use. Originality/value: To the best of the authors' knowledge, this study is the first to investigate the effect of green industry practices on the technical efficiency of Thai manufacturing enterprises. This study also encompasses analyses of the roles of internationalization, innovation and skill development
A 30-year overview of sodium-ion batteries
No full textSodium-ion batteries (NIBs) have emerged as a promising alternative to commercial lithium-ion batteries (LIBs) due to the similar properties of the Li and Na elements as well as the abundance and accessibility of Na resources. Most of the current research has been focused on the half-cell system (using Na metal as the counter electrode) to evaluate the performance of the cathode/anode/electrolyte. The relationship between the performance achieved in half cells and that obtained in full cells, however, has been neglected in much of this research. Additionally, the trade-off in the relationship between electrochemical performance and cost needs to be given more consideration. Therefore, systematic and comprehensive insights into the research status and key issues for the full-cell system need to be gained to advance its commercialization. Consequently, this review evaluates the recent progress based on various cathodes and highlights the most significant challenges for full cells. Several strategies have also been proposed to enhance the electrochemical performance of NIBs, including designing electrode materials, optimizing electrolytes, sodium compensation, and so forth. Finally, perspectives and outlooks are provided to guide future research on sodium-ion full cells
Universal architecture and defect engineering dual strategy for hierarchical antimony phosphate composite toward fast and durable sodium storage
No full textAntimony (Sb)-based anode materials are feasible candidates for sodium-ion batteries (SIBs) due to their high theoretical specific capacity and excellent electrical conductivity. However, they still suffer from volume distortion, structural collapse, and ionic conduction interruption upon cycling. Herein, a hierarchical array-like nanofiber structure was designed to address these limitations by combining architecture engineering and anion tuning strategy, in which SbPO4−x with oxygen vacancy nanosheet arrays are anchored on the surface of interwoven carbon nanofibers (SbPO4−x@CNFs). In particular, bulky PO43− anions mitigate the large volume distortion and generate Na3PO4 with high ionic conductivity, collectively improving cyclic stability and ionic transport efficiency. The abundant oxygen vacancies substantially boost the intrinsic electronic conductivity of SbPO4, further accelerating the reaction dynamics. In addition, hierarchical fibrous structures provide abundant active sites, construct efficient conducting networks, and enhance the electron/ion transport capacity. Benefiting from the advanced structural design, the SbPO4−x@CNFs electrodes exhibit outstanding cycling stability (1000 cycles at 1.0 A g−1 with capacity decay of 0.05% per cycle) and rapid sodium storage performance (293.8 mA h g−1 at 5.0 A g−1). Importantly, systematic in-/ex-situ techniques have revealed the “multi-step conversion-alloying” reaction process and the “battery-capacitor dual-mode” sodium-storage mechanism. This work provides valuable insights into the design of anode materials for advanced SIBs with elevated stability and superior rate performance
Machine learning-assisted composition design of W-free Co-based superalloys with high γ′-solvus temperature and low density
No full textDeveloping materials with multiple desired characteristics is a tremendous challenge, particularly in an elaborate material system. Herein, a machine learning assisted material design strategy was applied to simultaneously optimize dual target attributes by considering γ′ solvus temperature and alloy density of multi-component Co-based superalloys. To verify the soundness of our strategy, four alloys were selected and experimentally synthesized from >510,000 candidates, each of them possessing γ′ solvus temperature exceeding 1200 °C and alloy density below 8.3 g/cm3. Of those, Co-35Ni-12Al-5Ti-3V-3Cr-2Ta-2Mo (at.%) possesses the highest γ′ solvus temperature of 1250 °C and lower density of 8.2 g/cm3. This article validates a straightforward strategy to guide rapid discovery and fabrication of multi-component materials with desired dual-performance characteristics
Computational evaluation of Li-decorated α−C3N2 as a room temperature reversible hydrogen storage medium
No full textWe theoretically devised a novel complex by decorating Li atoms on the α-C3N2 for hydrogen storage, employing first-principles calculations. The findings reveal that: Li can be securely adsorbed onto the α-C3N2; the Li@α-C3N2 exhibits commendable thermal stability and boasts an excellent electronic structure due to the sp2 hybridization, making it highly conducive to hydrogen adsorption; the Li@α-C3N2 can adsorb 12 H2, achieving a capacity of 5.7 wt%; the average adsorption energy (0.215 eV ∼ 0.228 eV) falls within reversible hydrogen-storage range; the corresponding desorption temperature ranges from 277 K to 293 K. Additionally, the storage capacity of the Li@α-C3N2 can be as high as 5.7 wt% at 300 K and 10 bar. The adsorption mechanism can be attributed to a combination of electrostatic interactions, orbital interactions and van der Waals interactions between the substrate and hydrogen molecules
Synergistic coupling among Mg2B2O5, polycarbonate and N,N-dimethylformamide enhances the electrochemical performance of PVDF-HFP-based solid electrolyte
No full textPolymer solid electrolytes (SPEs) based on the [solvate-Li+] complex structure have promising prospects in lithium metal batteries (LMBs) due to their unique ion transport mechanism. However, the solvation structure may compromise the mechanical performance and safety, hindering practical application of SPEs. In this work, a composite solid electrolyte (CSE) is designed through the organic–inorganic synergistic interaction among N,N-dimethylformamide (DMF), polycarbonate (PC), and Mg2B2O5 in poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP). Flame-retardant Mg2B2O5 nanowires provide non-flammability to the prepared CSEs, and the addition of PC improves the dispersion of Mg2B2O5 nanowires. Simultaneously, the organic–inorganic synergistic action of PC plasticizer and Mg2B2O5 nanowires promotes the dissociation degree of LiTFSI and reduces the crystallinity of PVDF-HFP, enabling rapid Li ion transport. Additionally, Raman spectroscopy and DFT calculations confirm the coordination between Mg atoms in Mg2B2O5 and N atoms in DMF, which exhibits Lewis base-like behavior attacking adjacent C–F and C–H bonds in PVDF-HFP while inducing dehydrofluorination of PVDF-HFP. Based on the synergistic coupling of Mg2B2O5, PC, and DMF in the PVDF-HFP matrix, the prepared CSE exhibits superior ion conductivity (9.78 × 10−4 S cm−1). The assembled Li symmetric cells cycle stably for 3900 h at a current density of 0.1 mA cm−2 without short circuit. The LFP||Li cells assembled with PDL-Mg2B2O5/PC CSEs show excellent rate capability and cycling performance, with a capacity retention of 83.3% after 1000 cycles at 0.5 C. This work provides a novel approach for the practical application of organic–inorganic synergistic CSEs in LMBs
Twelve actions in healthcare to reduce carbon emissions
No full textThe pace of climate action is failing to meet the consequences of climate change and related environmental impacts. Globally, healthcare contributes 4% of carbon emissions, double that of the aviation industry. Often, >60% of healthcare emissions are derived from supply chain and procurement. Nurses comprise the single largest health workforce, it is therefore our moral imperative to act. We all have a responsibility to reduce, reuse, recycle, rethink, research, and advocate
An analytical approach of multi-dimensional Navier-Stokes equation in the framework of natural transform
No full textThis article introduces a new iterative transform method and homotopy perturbation transform method along with a natural transform to analyze the multi-dimensional Navier-Stokes equations. To solve the fractional-derivative, the Caputo-Fabrizio definition of the fractional derivative was employed. Four examples were considered to examine the efficacy and accuracy of the proposed methods. The efficiency and accuracy were also demonstrated by the solution comparison via graphs. The proposed methods’ convergence and uniqueness are also discussed. The methods mentioned above are straightforward and support a high rate of convergence
Assessing and managing frailty in advanced heart failure: An International Society for Heart and Lung Transplantation consensus statement
No full textFrailty is increasingly recognized as a salient condition in patients with heart failure (HF) as previous studies have determined that frailty is highly prevalent and prognostically significant, particularly in those with advanced HF. Definitions of frailty have included a variety of domains, including physical performance, sarcopenia, disability, comorbidity, and cognitive and psychological impairments, many of which are common in advanced HF. Multiple groups have recently recommended incorporating frailty assessments into clinical practice and research studies, indicating the need to standardize the definition and measurement of frailty in advanced HF. Therefore, the purpose of this consensus statement is to provide an integrated perspective on the definition of frailty in advanced HF and to generate a consensus on how to assess and manage frailty. We convened a group of HF clinicians and researchers who have expertise in frailty and related geriatric conditions in HF, and we focused on the patient with advanced HF. Herein, we provide an overview of frailty and how it has been applied in advanced HF (including potential mechanisms), present a definition of frailty, generate suggested assessments of frailty, provide guidance to differentiate frailty and related terms, and describe the assessment and management in advanced HF, including with surgical and nonsurgical interventions. We conclude by outlining critical evidence gaps, areas for future research, and clinical implementation
A Machine Learning-Driven Comparison of Ion Images Obtained by MALDI and MALDI-2 Mass Spectrometry Imaging
No full textMatrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) enables label-free imaging of biomolecules in biological tissues. However, many species remain undetected due to their poor ionization efficiencies. MALDI-2 (laser-induced post-ionization) is the most widely used post-ionization method for improving analyte ionization efficiencies. Mass spectra acquired using MALDI-2 constitute a combination of ions generated by both MALDI and MALDI-2 processes. Until now, no studies have focused on a detailed comparison between the ion images (as opposed to the generated m/z values) produced by MALDI and MALDI-2 for mass spectrometry imaging (MSI) experiments. Herein, we investigated the ion images produced by both MALDI and MALDI-2 on the same tissue section using correlation analysis (to explore similarities in ion images for ions common to both MALDI and MALDI-2) and a deep learning approach. For the latter, we used an analytical workflow based on the Xception convolutional neural network, which was originally trained for human-like natural image classification but which we adapted to elucidate similarities and differences in ion images obtained using the two MSI techniques. Correlation analysis demonstrated that common ions yielded similar spatial distributions with low-correlation species explained by either poor signal intensity in MALDI or the generation of additional unresolved signals using MALDI-2. Using the Xception-based method, we identified many regions in the t-SNE space of spatially similar ion images containing MALDI and MALDI-2-related signals. More notably, the method revealed distinct regions containing only MALDI-2 ion images with unique spatial distributions that were not observed using MALDI. These data explicitly demonstrate the ability of MALDI-2 to reveal molecular features and patterns as well as histological regions of interest that are not visible when using conventional MALDI