21 research outputs found
Intergenerational links, taxation, and wealth distribution
We extend one of the main findings in Bossmann et al. (2007)("Bequests, taxation and the distribution of wealth in a general equilibrium model," Journal of Public Economics, 91, 1247-1271). Bequest motives per se reduce wealth inequality. We show that the result holds for a stronger criterion of inequality comparison between distributions. Bossmann et al. (2007) use the coefficient of varation as the inequality measure. Our Lorenz dominance result implies their result. We also strengthen two other conclusions in Bossmann et al. (2007). Earnings ability inheritance could increase wealth inequality and estate taxes could decrease wealth inequality
Intergenerational links, taxation, and wealth distribution
We extend one of the main findings in Bossmann et al. (2007)("Bequests, taxation and the distribution of wealth in a general equilibrium model," Journal of Public Economics, 91, 1247-1271). Bequest motives per se reduce wealth inequality. We show that the result holds for a stronger criterion of inequality comparison between distributions. Bossmann et al. (2007) use the coefficient of varation as the inequality measure. Our Lorenz dominance result implies their result. We also strengthen two other conclusions in Bossmann et al. (2007). Earnings ability inheritance could increase wealth inequality and estate taxes could decrease wealth inequality
HighâEntropy Lithium Argyrodite Solid Electrolytes Enabling Stable AllâSolidâState Batteries
Superionic solid electrolytes (SEs) are essential for bulk-type solid-state battery (SSB) applications. Multicomponent SEs are recently attracting attention for their favorable charge-transport properties, however a thorough understanding of how configurational entropy (ÎSconf) affects ionic conductivity is lacking. Here, we successfully synthesized a series of halogen-rich lithium argyrodites with the general formula Li5.5PS4.5ClxBr1.5-x (0â€xâ€1.5). Using neutron powder diffraction and 31P magic-angle spinning nuclear magnetic resonance spectroscopy, the S2â/Clâ/Brâ occupancy on the anion sublattice was quantitatively analyzed. We show that disorder positively affects Li-ion dynamics, leading to a room-temperature ionic conductivity of 22.7â
mSâcmâ1 (9.6â
mSâcmâ1 in cold-pressed state) for Li5.5PS4.5Cl0.8Br0.7 (ÎSconf=1.98R). To the best of our knowledge, this is the first experimental evidence that configurational entropy of the anion sublattice correlates with ion mobility. Our results indicate the possibility of improving ionic conductivity in ceramic ion conductors by tailoring the degree of compositional complexity. Moreover, the Li5.5PS4.5Cl0.8Br0.7 SE allowed for stable cycling of single-crystal LiNi0.9Co0.06Mn0.04O2 (s-NCM90) composite cathodes in SSB cells, emphasizing that dual-substituted lithium argyrodites hold great promise in enabling high-performance electrochemical energy storage
Tuning the Valency of Heterogeneous AuâSilica Nanostructure via Controlled Ostwald Ripening Process
Morphology control
of interfaced heterogeneous nanostructure
composed of two different materials is critical for achieving desired
properties of the nanostructures. With heterogeneous Auâsilica
system as a case study, we explored the reaction mechanism that controlled
the number of overgrown silica domains on Au nanoparticle seeds. We
discovered in our system that three factors dominated the overgrowth
of silica on gold surface: (a) gold core size, (b) wettability of
the surface of the Au core (controlled by the amount of ligands),
and (c) reaction kinetics of hydrolysis of the silica precursor. In
particular, the latter two played distinct roles in triggering different
extents of Ostwald ripening and contributed to the symmetry breaking
of the morphology of the final product from coreâshell to coreâsatellite.
Specifically, polyÂ(acrylic acid) ligand decreased the local wettability
of the Au nanoparticle surface and resulted in discrete domain growth.
Adequate wetting introduced by 3-mercaptopropionic acid/cetyltrimethylammonium
ligands lowered the Auâsilica interface energy and stabilized
the silica domain in the later growth stage. After the initial nucleation
process, depending on the surface wettability and reaction kinetics,
Ostwald ripening of silica was triggered by the depletion field and
certain number of domains survived after the ripening process. By
tuning the core size, surface wettability, and reaction kinetics,
Auâsilica heterogeneous structure with desired number of silica
domains can be achieved. Since Ostwald ripening happens in many systems,
including metal, metal oxide, and semiconductors, our findings can
provide guidance to the synthesis of a wide span of heterogeneous
structures
Taxonomic Identification of the Arctic Strain <i>Nocardioides Arcticus</i> Sp. Nov. and Global Transcriptomic Analysis in Response to Hydrogen Peroxide Stress
Microorganisms living in polar regions rely on specialized mechanisms to adapt to extreme environments. The study of their stress adaptation mechanisms is a hot topic in international microbiology research. In this study, a bacterial strain (Arc9.136) isolated from Arctic marine sediments was selected to implement polyphasic taxonomic identification based on factors such as genetic characteristics, physiological and biochemical properties, and chemical composition. The results showed that strain Arc9.136 is classified to the genus Nocardioides, for which the name Nocardioides arcticus sp. nov. is proposed. The ozone hole over the Arctic leads to increased ultraviolet (UV-B) radiation, and low temperatures lead to increased dissolved content in seawater. These extreme environmental conditions result in oxidative stress, inducing a strong response in microorganisms. Based on the functional classification of significantly differentially expressed genes under 1 mM H2O2 stress, we suspect that Arc9.136 may respond to oxidative stress through the following strategies: (1) efficient utilization of various carbon sources to improve carbohydrate transport and metabolism; (2) altering ion transport and metabolism by decreasing the uptake of divalent iron (to avoid the Fenton reaction) and increasing the utilization of trivalent iron (to maintain intracellular iron homeostasis); (3) increasing the level of cell replication, DNA repair, and defense functions, repairing DNA damage caused by H2O2; (4) and changing the composition of lipids in the cell membrane and reducing the sensitivity of lipid peroxidation. This study provides insights into the stress resistance mechanisms of microorganisms in extreme environments and highlights the potential for developing low-temperature active microbial resources
Factors Influencing the Properties of Extrusion-Based 3D-Printed Alkali-Activated Fly Ash-Slag Mortar
The mix proportioning of extrusion-based 3D-printed cementitious material should balance printability and hardened properties. This paper investigated the effects of three key mix proportion parameters of 3D-printed alkali-activated fly ash/slag (3D-AAFS) mortar, i.e., the sand to binder (s/b) ratio, fly ash/ground granulated blast-furnace slag (FA/GGBS) ratio, and silicate modulus (Ms) of the activator, on extrudability, buildability, interlayer strength, and drying shrinkage. The results showed that the loss of extrudability and the development of buildability were accelerated by increasing the s/b ratio, decreasing the FA/GGBS ratio, or using a lower Ms activator. A rise in the s/b ratio improved the interlayer strength and reduces the drying shrinkage. Although increasing the FA/GGBS mass ratio from 1 to 3 led to a reduction of 35% in the interlayer bond strength, it decreased the shrinkage strain by half. A larger silicate modulus was beneficial to the interlayer bond strength, but it made shrinkage more serious. Moreover, a simple centroid design method was developed for optimizing the mix proportion of 3D-AAFS mortar to simultaneously meet the requirements of printability and hardened properties
Tailoring the electronic conductivity of high-loading cathode electrodes for practical sulfide-based all-solid-state batteries
Sulfide-based all-solid-state batteries (ASSBs) exhibit unparalleled application value due to the high ionic conductivity and good processability of sulfide solid electrolytes (SSEs). Carbon-based conductive agents (CAs) are often used in the construction of electronic conductive networks to achieve rapid electron transfer. However, CAs accelerate the formation of decomposition products of SSEs, and their effects on sulfide-based ASSBs are not fully understood. Herein, the effect of CAs (super P, vaper-grown carbon fibers, and carbon nanotubes) on the performance of sulfide-based ASSBs is investigated under different cathode active materials mass loading (8 and 25 âmg·cmâ2). The results show that under low mass loading, the side reaction between the CAs and the SSEs deteriorates the performance of the cell, while the charge transfer promotion caused by the addition of CAs is only manifested under high mass loading. Furthermore, the gradient design strategy (enrichment of CAs near the current collector side and depletion of CAs near the electrolyte side) is applied to maximize the benefits of CAs in electron transport and reduce the adverse effects of CAs. The charge carrier transport barrier inside the high mass loading electrode is significantly reduced through the regulation of electronic conductivity. Consequently, the optimized electrode achieves a high areal capacity of 5.6 âmAh·cmâ2 at high current density (1.25 âmA·cmâ2, 0.2 âC) at 25 °C with a capacity retention of 87.85% after 100 cycles. This work provides a promising way for the design of high-mass loading electrodes with practical application value
Ion Dynamics of Water-in-Salt Electrolyte with Organic Solvents in Nanoporous Supercapacitor Electrodes
Water-in-salt electrolytes blended with organics solvents, that is, organic solvent/water mixed electrolytes, are promising for applications in next-generation energy storage devices vitally needed for industrial electrification and decarbonization. However, the electrolyte ion diffusion behaviors within nanoporous supercapacitor electrodes are poorly understood. Here a systematic investigation into supercapacitor resistances and ion kinetics is carried out experimentally and with numerical simulations. The electrochemical results on the nanoporous electrodes reveal a nonmonotonic (decreasing, increasing, and then decreasing) trend of supercapacitor resistances with increasing solvent mobility, challenging the long-held views that supercapacitor resistances decrease with elevated mobility of organic solvent. The abnormal trend is examined by numerical molecular dynamics simulations of electrolyte ion diffusion within 0.95 nm nanochannels. The electrolyte conductivity is related to cationâanion interactions within nanochannels. We further confirm the crucial interplay of the van der Waals sizes of solvent molecules and channel width in determining electrolyte conductivity in nanoporous electrodes.</p
Preparation and properties of sulfide solid state electrolyte Li6PS5Cl by ball milling-solid phase sintering
Li6PS5Cl (LPSC), a sulfide solid-state electrolyte with an argyrodite structure, is one of the ideal electrolyte materials for the construction of all-solid-state lithium-ion batteries.It has good development prospects because of its high ionic conductivity (>3Ă10-3 S·cm-1) and good stability to lithium. In this work, LPSC was prepared by the combination of high-energy ball milling and inert atmosphere solid-phase sintering, and powder X-ray diffraction, Raman spectra, and scanning electron microscopy were used to investigate the effects of the preparation process on the structure, composition, electrical properties, and ion conductivity of LPSC. The results show that the extended ball milling time is beneficial to the amorphization and subsequent sintering of the LPSC precursor powder. The increase of the sintering temperature will promote the physical purity and electrical conductivity of the prepared LPSC electrolyte, but the high sintering temperature will lead to the decomposition of LPSC. The LPSC prepared by 8 h ball milling and 500â sintering has the highest ion/electron conductivity ratio (2.091Ă105) at room temperature, with ionic conductivity up to 4.049Ă10-3 S·cm-1 and electronic conductivity only 1.936Ă10-8 S·cm-1. The 712 NCM/LPSC/In-Li all-solid-state battery prepared with this electrolyte has a first-turn discharge specific capacity of 151.3 mAh·g-1 at a charge/discharge ratio of 0.1 C, and has excellent cycling stability
PnLRR-RLK27, a novel leucine-rich repeats receptor-like protein kinase from the Antarctic moss <i>Pohlia nutans</i>, positively regulates salinity and oxidation-stress tolerance
<div><p>Leucine-rich repeats receptor-like kinases (LRR-RLKs) play important roles in plant growth and development as well as stress responses. Here, 56 LRR-RLK genes were identified in the Antarctic moss <i>Pohlia nutans</i> transcriptome, which were further classified into 11 subgroups based on their extracellular domain. Of them, PnLRR-RLK27 belongs to the LRR II subgroup and its expression was significantly induced by abiotic stresses. Subcellular localization analysis showed that PnLRR-RLK27 was a plasma membrane protein. The overexpression of PnLRR-RLK27 in <i>Physcomitrella</i> significantly enhanced the salinity and ABA tolerance in their gametophyte growth. Similarly, PnLRR-RLK27 heterologous expression in <i>Arabidopsis</i> increased the salinity and ABA tolerance in their seed germination and early root growth as well as the tolerance to oxidative stress. PnLRR-RLK27 overproduction in these transgenic plants increased the expression of salt stress/ABA-related genes. Furthermore, PnLRR-RLK27 increased the activities of reactive oxygen species (ROS) scavengers and reduced the levels of malondialdehyde (MDA) and ROS. Taken together, these results suggested that PnLRR-RLK27 as a signaling regulator confer abiotic stress response associated with the regulation of the stress- and ABA-mediated signaling network.</p></div