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Climate change mitigation by increased paper recycling can alleviate the two-sided pressure on the Swedish forest sector: supplying growing demands for wood-based products and increasing the forest carbon sink. This study assesses two scenarios for making use of a reduced demand for primary pulp resulting from an increased paper recycling rate in Sweden, from the present 72% to 78%. A Conservation scenario uses the saved primary pulp to reduce pulplog harvests so as to increase the forest carbon sink concomitant with constant overall wood product supply. In contrast, a Substitution scenario uses the saved primary pulp to produce man-made cellulosic fibers (MMCF) from dissolving pulp replacing cotton fiber, implying increased overall wood product supply. Our results suggest that utilizing efficiency gains in paper recycling to reduce pulplog harvests is better from a climate change mitigation perspective than producing additional MMCF to substitute cotton fiber. This conclusion holds even when assuming the use of by-products from dissolving pulp making and an indirect increase in MMCF availability. Hence, unless joint improvements across the value chain materialize, the best climate change mitigation option from increased paper recycling in Sweden would seemingly be to reduce fellings rather than producing additional MMCF.

Paper and pencil have shown wide applicability in the area of flexible electronics. Devices based on paper and pencil offer distinctive advantages, including rapid, straightforward, and cost-effective fabrication, as well as recyclability and eco-friendly characteristics. There are several concepts that have been demonstrated using paper and pencil including thermoelectric, strain gauges, capacitive sensors, and biomedical devices. This review article summarizes state of art of pencil-based thermoelectric devices on paper and their future potential.

Background : The incorporation of industrial wastes, such as wood ash and paper sludge, as soil amendments is vital for both environmental sustainability and agroecosystem productivity. Herein, we evaluated the effects of wood ash and paper sludge alone and in combination with biochar on the physicochemical properties and heavy metal leaching risks in podzolic soils. Methods : The treatments included limestone (control), wood ash, paper sludge, wood ash+paper sludge, limestone+biochar, wood ash+biochar, paper sludge+biochar and wood ash+paper sludge+biochar, arranged in a 4 × 2 factorial design with three replicates. The Hydrus-1D model was employed to simulate the water movement under these soil amendments using leaching colums. Results : Overall, wood ash, paper sludge and biochar application significantly increased the pH of amended soil compared to control. Paper sludge amended treatments alone or in combination with biochar significantly decreased bulk density (8%–17%) and increased the total porosity (14%–25%). While biochar addition to wood ash and paper sludge significantly reduced the concentrations of Cd (by 6.42%), Co (by 10.95%), Cu (by 11.76%), Pb (by 30%) and Ni (by 3.75%) in the collected leachates. The treatment paper sludge + biochar was found to be the most effective treatment to retain the heavy metals, with maximum plant available water (0.28 cm ^3 cm ^−3 ) and field capacity (0.36 cm ^3 cm ^−3 ) compared to control treatment. The predictions from Hydrus-1D showed that paper mill wastes with biochar has a significant potential to increase the volumetric moisture contents of amended podzolic soil, with the simulated leaching times and saturation levels closely aligning with the measured values. Conclusion : paper sludge + biochar treatment showed improved soil physicochemical properties and displayed lower heavy metals than allowed limits to be used in soil. Further, experiments are needed to assess the effects of papermill waste products on podzolic soil properties under variable field conditions.

Environmental sustainability and the effective use of renewable resources are critical subjects that need to be integrated into our educational systems through practical, hands-on learning. This paper focuses on the fabrication of aluminium-air batteries using waste materials, providing an innovative and cost-effective DIY approach to energy storage education. Utilizing aluminium from food packaging and graphite from pencils, this study demonstrates the construction and functionality of an aluminium-air battery to run an LED, highlighting its potential applications in educational settings and low-cost energy solutions. The paper aims to inspire the adoption of environmentally friendly practices and enhance students' understanding of electrochemical energy conversion through accessible and engaging DIY projects. [ABSTRACT FROM AUTHOR]

We study a three-species cyclic model whose organisms are vulnerable to contamination with an infectious disease which propagates person-to-person. We consider that individuals of one species perform a self-preservation strategy by reducing the mobility rate to minimise infection risk whenever an epidemic outbreak reaches the neighbourhood. Running stochastic simulations, we quantify the changes in spatial patterns induced by unevenness in the cyclic game introduced by the mobility restriction strategy of organisms of one out of the species. Our findings show that variations in disease virulence impact the benefits of dispersal limitation reaction, with the relative reduction of the organisms’ infection risk accentuating in surges of less contagious or deadlier diseases. The effectiveness of the mobility restriction tactic depends on the deceleration level and the fraction of infected neighbours which is considered too dangerous, thus triggering the defensive strategy. If each organism promptly reacts to the arrival of the first viral vectors in its surroundings with strict mobility reduction, contamination risk decreases significantly. Our conclusions may help biologists understand the impact of defensive strategies in ecosystems during an epidemic.

A crucial yet challenging task in galaxy evolution studies is the identification of distant merging galaxies, a task that suffers from a variety of issues ranging from telescope sensitivities and limitations to the inherently chaotic morphologies of young galaxies. In this paper, we use random forests and convolutional neural networks to identify high-redshift JWST Cosmic Evolution Early Release Science Survey (CEERS) galaxy mergers. We train these algorithms on simulated 3 < z < 5 CEERS galaxies created from the IllustrisTNG subhalo morphologies and the Santa Cruz SAM light cone. We apply our models to observed CEERS galaxies at 3 < z < 5. We find that our models correctly classify ∼60%–70% of simulated merging and nonmerging galaxies; better performance on the merger class comes at the expense of misclassifying more nonmergers. We could achieve more accurate classifications, as well as test for a dependency on physical parameters such as gas fraction, mass ratio, and relative orbits, by curating larger training sets. When applied to real CEERS galaxies using visual classifications as ground truth, the random forests correctly classified 40%–60% of mergers and nonmergers at 3 < z < 4 but tended to classify most objects as nonmergers at 4 < z < 5 (misclassifying ∼70% of visually classified mergers). On the other hand, the CNNs tended to classify most objects as mergers across all redshifts (misclassifying 80%–90% of visually classified nonmergers). We investigate what features the models find most useful, as well as the characteristics of false positives and false negatives, and also calculate merger rates derived from the identifications made by the models.

Lithium-ion batteries (LIBs) have revolutionized portable electronics, yet their conventional graphite anodes face capacity limitations. Integrating graphene and 3D molybdenum disulfide (MoS2) offers a promising solution. Ensuring a uniform distribution of 3D MoS2 nanostructures within a graphene matrix is crucial for optimizing battery performance and preventing issues like agglomeration and capacity degradation. This study focuses on synthesizing a uniformly distributed paper wad structure by optimizing a composite of reduced graphene oxide RGO@MoS2 through structural and morphological analyses. Three composites with varying graphene content were synthesized, revealing that the optimized sample containing 30 mg RGO demonstrates beneficial synergy between MoS2 and RGO. The interconnected RGO network enhances reactivity and conductivity, addressing MoS2 aggregation. Experimental results exhibit an initially superior capacity of 911 mAh g−1, retained at 851 mAh g−1 even after 100 cycles at 0.1 A g−1 current density, showcasing improved rate efficiency and long-term stability. This research underscores the pivotal role of graphene content in customizing RGO@MoS2 composites for enhanced LIB performance. [ABSTRACT FROM AUTHOR]

Call For Papers for the 247th ECS Meeting, Montreal, Canada, May 18-22, 2025 [ABSTRACT FROM AUTHOR]

Daphne bholua Buch. -Ham. ex D. Don (Thymelaeaceae) is a woody shrub native to the temperate forests of the Himalaya. Since the 12th century, the bark of D. bholua has been used as a raw material for handmade paper in Nepal, and employed for value-added products, including government documents, and religious texts. However, unsustainable commercial harvesting now threatens this centuries-old artisanal tradition. To inform and improve the conservation of this important species, we evaluated its habitat characteristics, size class distribution, and regeneration status along an elevation gradient (1900–2500 m) in Madane Mountain, central Nepal. We established 108 plots (5 m× 5 m) at three sites, each with three canopy types: closed, semi-closed, and open. We analyzed habitat characteristics, considering variations in physical and topographic variables and patterns of associated species in different elevation sites. D. bholua exhibited the highest mean density at higher elevations with minimal disturbance, whereas the lowest elevation site, experienced greater human disturbance, with the lowest density. Furthermore, the population structure displayed a ‘reverse J-shaped’ curve, suggesting favorable conditions for natural recruitment and regeneration. Our research findings also indicate that D. bholua populations thrive in semi-closed forest canopies, particularly when associated with Rhododendron arboreum , Quercus semecarpifolia , and Sarcococca coriacea. The outcomes may hold significant value for policymakers, conservationists, harvesters, paper manufacturers, and regulatory bodies aiding in development of environmentally sound conservation programs tailored to various elevations. Our key recommendation may appear surprising: we advise establishing a small, meticulously managed hand papermaking industry in the villages linked to Madane and nearby areas. This initiative would generate supplemental income and produce a culturally valuable and economically marketable product.

Carbon nanofoam papers (CNFPs) serve as device-ready negative electrodes for nonaqueous sodium-ion (Na-ion) batteries, with fast and reversible Na+ storage at the aerogel-like, disordered carbon nanofoam. These binder-free, scalable electrode architectures are not only advantageous for the construction of practical, high-performance Na-ion cells, but are also effective platforms to analyze charge-storage mechanisms. We use in situ optical imaging at the outer surfaces of CNFPs in a Na half-cell to track the distinctive color changes that accompany the multi-stage Na+-storage processes on scanning these electrodes through their active voltage window (0–2 V vs Na∣Na+). We observe that electrochromic transitions ― black in the native (unsodiated) state→blue→red/gold ― occur primarily with deep levels of sodiation at <0.5 V vs Na∣Na+. In situ Raman scattering measurements in the same optical cell show that these color changes correlate with shifts in the characteristic G-band Raman peak that would indicate bulk Na+ insertion into nanoscopic graphitic domains within the aerogel-like carbon. The CNFPs also exhibit appreciable Na-ion storage at higher voltage (0.5–2 V vs Na∣Na+), which can be ascribed to surface-based mechanisms that are accompanied by shifts in the D-band Raman peak, but which do not induce appreciable color change [ABSTRACT FROM AUTHOR]

Climate changes may affect ecosystems destabilising relationships among species. We investigate the spatial rock-paper-scissors models with a regional unevenness that reduces the selection capacity of organisms of one species. Our results show that the regionally weak species predominates in the local ecosystem, while spiral patterns appear far from the region, where individuals of every species play the rock-paper-scissors game with the same strength. Because the weak species controls all local territory, it is attractive for the other species to enter the local ecosystem to conquer the territory. However, our stochastic simulations show that the transitory waves formed when organisms of the strong species reach the region are quickly destroyed because of local strength unbalance in the selection game rules. Computing the effect of the topology on population dynamics, we find that the prevalence of the weak species becomes more significant if the transition of the selection capacity to the area of uneven rock-paper-scissors rules is smooth. Finally, our findings show that the biodiversity loss due to the arising of regional unevenness is minimised if the transition to the region where the cyclic game is unbalanced is abrupt. Our results may be helpful to biologists in comprehending the consequences of changes in the environmental conditions on species coexistence and spatial patterns in complex systems.

Handling and storing the immense amounts of data native to the information age is a major challenge in terms of technological sustainability and energy demand. To date, tape storage remains the most widespread method for data archiving, while DNA data storage appears to offer the best data density and long-term stability in the future. However, DNA data storage is still in its infancy primarily due to economic and accessibility challenges. This emphasizes the need for more practical and readily available alternatives. We present a method for data storage utilizing inkjet printable quantum dots on paper with photoluminescence (PL) readout. Our proof of principle study showcases the ability to print and stack multiple bits of data on a single spot by exploiting the unique PL properties of quantum dots. This approach utilizes easily accessible resources, including a consumer-grade printer and paper as the substrate. Additionally, we perform initial stability tests, investigate scalability by controlling emission intensity, and evaluate the potential data density achievable by our approach.

We report for the first time MoS2/CNT hybrid nanostructures for memristor applications on flexible and bio-degradable cellulose paper. In our approach, we varied two different weight percentages (10% and 20%) of CNT's in MoS2 to improve the MoS2 conductivity and investigate the memristor device characteristics. The device with 10% CNT shows a low V SET voltage of 2.5 V, which is comparatively small for planar devices geometries. The device exhibits a long data retention time and cyclic current–voltage stability of ∼104 s and 102 cycles, making it a potential candidate in flexible painted electronics. Along with good electrical performance, it also demonstrates a high mechanical stability for 1000 bending cycles. The conduction mechanism in the MoS2-CNT hybrid structure is corroborated by percolation and defect-induced filament formation. Additionally, the device displays synaptic plasticity performance, simulating potentiation and depression processes. Furthermore, such flexible and biodegradable cellulose-based paper electronics may pave the way to address the environmental pollution caused by electronic waste in the near future. [ABSTRACT FROM AUTHOR]

Filter cloth brush-coating (FCBC), using soft filter cloth as a brush-coating medium, in conjunction with viscous silver nanowire (AgNW) conductive solution, is used to prepare AgNW conductive films. The density and uniformity of AgNWs deposited on the substrate are controlled by the interplay between the filter cloth aperture, the conductive solution viscosity, and the brush-coating speed. Further, with appropriate AgNW concentration and flow rate, uniform AgNW transparent conductive film with sheet resistance of 18 Ω sq−1 and transmittance of 94% at 550 nm is acquired by FCBC. Due to the precise control of the coating process in FCBC, large-area uniform AgNW conductive film fabricated on printing paper has a low non-uniformity factor of 1.2% at a sheet resistance of 19.0 Ω sq−1. The resultant paper-based AgNW film heater shows sensitive and stable heating performance. FCBC shows great potential in producing large-area uniform AgNW films on various substrates. [ABSTRACT FROM AUTHOR]

The determination of the dielectric breakdown strengths of microstructurally heterogeneous materials has been a primarily experimental endeavor. We report the development of a microstructure-level model for computationally predicting the breakdown strength and analyzing the interactions between electromagnetic pulses (EMP) and the constituents in a composite of cellulose-based paper and mineral oil found in electrical transformers. The model allows explicit simulation of the material breakdown process by tracking the transition of dielectric constituents from non-conductive to conductive states. The focus is on the electric fields induced in the materials and the overall conditions for dielectric breakdown (defined as the onset of avalanche) caused by the electric field induced in the composite. Responses to three distinct pulse shapes, i.e., Steep Front (SF), Lightning (L), and AC with spectra spanning 60–9 × 10 ^5 Hz are considered. It is found that the breakdown strength of the material is significantly affected by microstructure heterogeneities, the spatial variations of the constituent properties, and the pulse shapes. A probabilistic characterization of the breakdown strength is computationally obtained and compared with experimental measurements. Although one particular material is analyzed, the model and approach are applicable to other heterogeneous materials as well.

We introduce and study the spatial replicator equation with higher order interactions and both infinite (spatially homogeneous) populations and finite (spatially inhomogeneous) populations. We show that in the special case of three strategies (rock–paper–scissors) higher order interaction terms allow travelling waves to emerge in non-declining finite populations. We show that these travelling waves arise from diffusion stabilisation of an unstable interior equilibrium point that is present in the aspatial dynamics. Based on these observations and prior results, we offer two conjectures whose proofs would fully generalise our results to all odd cyclic games, both with and without higher order interactions, assuming a spatial replicator dynamic. Intriguingly, these generalisations for N ⩾ 5 strategies seem to require declining populations, as we show in our discussion. [ABSTRACT FROM AUTHOR]

Encouraged by the goal of achieving net-zero carbon emission by 2050, the exploration of insulating material becomes one of the core projects to the electrical equipment innovations. The rise of composites enables the insulating material to be endowed with more functions. By this concern, adopting the coupling agents is one of the effective methods to improve the compatibility of composites, which highly strengthens the desired properties. The functional groups of coupling agents, nevertheless, could not always show a positive impact to access enhanced properties. In this work, four types of silane coupling agents including amino-propyl, glycidyletheroxy-propyl (GP), vinyl, and methacryloxy-propyl functional groups are employed to modify the aluminum nitride (AlN) fillers, and the modification effects on the insulating and thermal conductivity of the AlN/poly(m-phenylenedicarbonyl-m-phenylenediamine) (PMIA) composite paper are systematically investigated and compared. The results show that a proper coupling agent is beneficial to the uniform dispersion of the inorganic filler in the organic matrix and highly contributes to their interface quality, where the heat transfer path is established that boosts the heat dissipation. By tailoring the trap depth and density toward deeper and higher, the carrier transport is highly confined which enhances the breakdown strength to a large extent. Therefore, high breakdown strength and thermal conductivity of 182.9 kV mm−1 and 0.302 W (m·K)−1, respectively, are achieved in the GP modified AlN/PMIA paper, which are 16.7% and 167.4% higher than that of pure PMIA paper. [ABSTRACT FROM AUTHOR]

Version 11 of the chianti database and software package is presented. Advanced ionization equilibrium models have been added for low charge states of seven elements (C, N, O, Ne, Mg, Si, and S), and represent a significant improvement especially when modeling the solar transition region. The models include the effects of higher electron density and charge transfer on ionization and recombination rates. As an illustration of the difference these models make, a synthetic spectrum is calculated for an electron pressure of 7 × 10 ^15 cm ^−3 K and compared with an active region observation from HRTS. Increases are seen in factors of 2–5 in the predicted radiances of the strongest lines in the UV from Si iv , C iv , and N v , compared to the previous modeling using the coronal approximation. Much better agreement (within 20%) with the observations is found for the majority of the lines. The new atomic models better equip both those who are studying the transition region and those who are interpreting the emission from higher-density astrophysical and laboratory plasma. In addition to the advanced models, several ion data sets have been added or updated, and data for the radiative recombination energy loss rate have been updated.

We use James Webb Space Telescope Near-Infrared Camera Wide Field Slitless Spectroscopy (NIRCam WFSS) and the Near-Infrared spectrograph (NIRSpec) in the Cosmic Evolution Early Release survey to measure rest-frame optical emission-line ratios of 155 galaxies at z > 2. The blind NIRCam grism observations include a sample of galaxies with bright emission lines that were not observed on the NIRSpec masks. We study the changes of the H α , [O III ]/H β , and [Ne III ]/[O II ] emission lines in terms of redshift by comparing to lower-redshift SDSS, CLEAR, and MOSDEF samples. We find a significant (>3 σ ) correlation between [O III ]/H β with redshift, while [Ne III ]/[O II ] has a marginal (2 σ ) correlation with redshift. We compare [O III ]/H β and [Ne III ]/[O II ] to stellar mass and H β SFR. We find that both emission-line ratios have a correlation with H β SFR and an anticorrelation with stellar mass across the redshifts 0 < z < 9. Comparison with MAPPINGS V models indicates that these trends are consistent with lower metallicity and higher ionization in low-mass and high-SFR galaxies. We additionally compare to IllustrisTNG predictions and find that they effectively describe the highest [O III ]/H β ratios observed in our sample, without the need to invoke MAPPINGS models with significant shock ionization components.

Recent progress in the in situ synthesise of various nanomaterials has gained tremendous interest and wide applications in various fields. For the first time to the best of our knowledge, this work reports a methodology of ultra-fast in situ synthesis of cobalt–cobalt oxide-reduced graphene oxide (Co−Co3O4−rGO (CC–rGO)) composite by laser ablation. The photothermal reduction technique was leveraged to develop the CC–rGO. For this, a low-cost 450 nm blue diode laser was irradiated onto a grade 1 filter paper in the presence of cobalt ions readily patterns the carbon matrix of paper to the composite material. Moreover, the variation of cobalt concentrations from 0.1–0.5 M led to structural and morphological changes. Standard techniques were adopted for thorough characterizations of developed sensor material for conductivity analysis, specific surface area, crystal-structural information, surface morphology, and chemical composition. The observed results were highly promoting towards the electrochemical sensing applications. Further, the developed sensor was found to be highly selective toward detecting a vital bio analyte alkaline phosphatase (ALP). The sensors performance was highly significant in the linear range of 10–800 mU l−1 with a detection limit of 10.13 mU l−1. The sensors applicability was further validated in actual human serum samples via a recovery-based approach. In the future, the developed in situ material methodology can begin a rapid composite material synthesis at a larger scale. [ABSTRACT FROM AUTHOR]

Cadmium ion (Cd2+) is one of the toxic heavy metals in the environment. Even small amounts of Cd2+ may cause environmental pollution and threaten human life and health. Here, an electrochemical sensor for Cd2+ detection was established using a complex of carbon fiber paper (CFP), CoMOF, AuNPs, and glutathione as the conductive substrate (CFP/CoMOF/AuNPs/GSH). Compared with traditional methods for heavy metals detection, electrochemistry owns the advantages of high sensitivity, easy miniaturization, and portability. In addition, general conductive substrate is replaced by a new nanomaterial, CFP/CoMOF/AuNPs/GSH, which improves the performance greatly. In the presence of Cd2+, GSH is chelated to Cd2+, resulting in a redox peak appearing around -0.84 V. Thus, a sensitive and easily portable electrochemical sensor for Cd2+ detection has been developed. Under optimal conditions, the established electrochemical sensor achieves Cd2+ detection low to 1 nM. Selectivity and reproducibility experiments show that the sensor has good analytical performance. This provides a direction for the use of electrochemistry to detect heavy metal ions. [ABSTRACT FROM AUTHOR]

A high-performance paper electrode is fabricated through coating polypyrrole (PPy) on ordinary laboratory filter paper via a traditional interfacial polymerization method with perchloric acid (HClO4) as a dopant. Owing to the superior mechanical flexibility and environmental stability of the free standing PPy paper, the robust electrode displays an ultrahigh capacitance of 1650 mF cm−2 and remarkable cyclic stability of losing 11.66% after cycling for 10000 times in a three-electrode system. More importantly, the areal specific capacitance has only decreased by 0.08% after five months. Furthermore, by employing the synthesized PPy papers as electrodes and the PVA-H2SO4 gel as electrolyte, the assembled all-solid-state supercapacitor with an areal specific capacitance of 566.5 mF cm−2 is achieved, corresponding to an areal energy density of 38.55 μW h cm−2 and power density of 0.17 mW cm−2. These results suggest that the simple synthesis of PPy paper electrode pave a promising way to exploit flexible and durable energy storage applications. [ABSTRACT FROM AUTHOR]

The Cosmic Evolution Early Release Science program observed the Extended Groth Strip (EGS) with the Mid-Infrared Instrument (MIRI) on the James Webb Space Telescope (JWST) in 2022. In this paper, we discuss the four MIRI pointings that observed with longer-wavelength filters, including F770W, F1000W, F1280W, F1500W, F1800W, and F2100W. We compare the MIRI galaxies with the Spitzer/MIPS 24 μ m population in the EGS field. We find that MIRI can observe an order of magnitude deeper than MIPS in significantly shorter integration times, attributable to JWST's much larger aperture and MIRI’s improved sensitivity. MIRI is exceptionally good at finding faint ( L _IR < 10 ^10 L _⊙ ) galaxies at z ∼ 1–2. We find that a significant portion of MIRI galaxies are “mid-IR weak”—they have strong near-IR emission and relatively weaker mid-IR emission, and most of the star formation is unobscured. We present new IR templates that capture how the mid-to-near-IR emission changes with increasing infrared luminosity. We present two color–color diagrams to separate mid-IR weak galaxies and active galactic nuclei (AGN) from dusty star-forming galaxies and find that these color diagrams are most effective when used in conjunction with each other. We present the first number counts of 10 μ m sources and find that there are ≲10 IR AGN per MIRI pointing, possibly due to the difficulty of distinguishing AGN from intrinsically mid-IR weak galaxies (due to low metallicities or dust content). We conclude that MIRI is most effective at observing moderate-luminosity ( L _IR = 10 ^9 –10 ^10 L _⊙ ) galaxies at z = 1–2, and that photometry alone is not effective at identifying AGN within this faint population.

Transition metal (Fe, Ni, Co)-based hydroxides, especially nickel hydroxide (Ni(OH)2), have been considered as promising candidate for hydrogen evolution reaction (HER) because of their low cost, natural abundance and high catalytic performance. However, the catalytic performance of Ni(OH)2 is still unsatisfactory for practical application due to its relatively low electrical conductivity. Here, a highly conductive silver nanowires (AgNWs) network is prepared on filter paper, followed by the electrodeposition of Ni(OH)2 on the surface of AgNWs to form AgNWs@Ni(OH)2 core-shell structure. In comparison with pure Ni(OH)2 (376 mV at −10 mA cm−2), the optimized AgNWs@Ni(OH)2 electrode can exhibit about 3-fold enhanced HER performance, which achieves a lower overpotential of 123 mV at the current density of −10 mA cm−2, and a small Tafel slope of 76 mV dec−1 in 1 M KOH electrolyte. Besides the superior activity, the AgNWs@Ni(OH)2 electrode also shows a better durability. Such enhanced catalytic performance benefits from the high conductivity of AgNWs network to facilitate electron transfer, and the synergistic interaction between AgNWs and Ni(OH)2. This work also provides general strategies to design highly active HER electrocatalysts by utilizing highly conductive AgNWs to form core-shell architecture. [ABSTRACT FROM AUTHOR]

Mid-infrared (mid-IR) observations are powerful in identifying heavily obscured active galactic nuclei (AGN) that have weak emission in other wavelengths. Data from the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope provides an excellent opportunity to perform such studies. We take advantage of the MIRI imaging data from the Cosmic Evolution Early Release Science Survey to investigate the AGN population in the distant universe. We estimate the source properties of MIRI-selected objects by utilizing spectral energy distribution (SED) modeling, and classify them into star-forming galaxies (SFs), SF-AGN mixed objects, and AGN. The source numbers of these types are 433, 102, and 25, respectively, from four MIRI pointings covering ∼9 arcmin ^2 . The sample spans a redshift range of ≈0–5. We derive the median SEDs for all three source types, respectively, and publicly release them. The median MIRI SED of AGN is similar to the typical SEDs of hot dust-obscured galaxies and Seyfert 2s, for which the mid-IR SEDs are dominated by emission from AGN-heated hot dust. Based on our SED-fit results, we estimate the black hole accretion density (BHAD; i.e., total BH growth rate per comoving volume) as a function of redshift. At z < 3, the resulting BHAD agrees with the X-ray measurements in general. At z > 3, we identify a total of 27 AGN and SF-AGN mixed objects, leading to that our high- z BHAD is substantially higher than the X-ray results (∼0.5 dex at z ≈ 3–5). This difference indicates MIRI can identify a large population of heavily obscured AGN missed by X-ray surveys at high redshifts.

We present results from the Cosmic Evolution Early Release Survey on the stellar population parameters for 28 galaxies with redshifts 4 < z < 9 using imaging data from the James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) combined with data from the Hubble Space Telescope and the Spitzer Space Telescope. The JWST/MIRI 5.6 and 7.7 μ m data extend the coverage of the rest-frame spectral energy distribution to nearly 1 μ m for galaxies in this redshift range. By modeling the galaxies’ SEDs the MIRI data show that the galaxies have, on average, rest-frame UV (1600 Å)— I -band colors 0.4 mag bluer than derived when using photometry that lacks MIRI. Therefore, the galaxies have lower ratios of stellar mass to light. The MIRI data reduce the stellar masses by $\langle {\rm{\Delta }}\mathrm{log}{M}_{* }\rangle =0.25$ dex at 4 < z < 6 and 0.37 dex at 6 < z < 9. This also reduces the star formation rates (SFRs) by 〈ΔlogSFR〉 = 0.14 dex at 4 < z < 6 and 0.27 dex at 6 < z < 9. The MIRI data also improve constraints on the allowable stellar mass formed in early star formation. We model this using a star formation history that includes both a “burst” at z _f = 100 and a slowly varying (“delayed- τ ”) model. The MIRI data reduce the allowable stellar mass by 0.6 dex at 4 < z < 6 and by ≈1 dex at 6 < z < 9. Applying these results globally, this reduces the cosmic stellar-mass density by an order of magnitude in the early Universe ( z ≈ 9). Therefore, observations of rest-frame ≳1 μ m are paramount for constraining the stellar-mass buildup in galaxies at very high redshifts.

We present an investigation into the first 500 Myr of galaxy evolution from the Cosmic Evolution Early Release Science (CEERS) survey. CEERS, one of 13 JWST ERS programs, targets galaxy formation from z ∼ 0.5 to >10 using several imaging and spectroscopic modes. We make use of the first epoch of CEERS NIRCam imaging, spanning 35.5 arcmin ^2 , to search for candidate galaxies at z > 9. Following a detailed data reduction process implementing several custom steps to produce high-quality reduced images, we perform multiband photometry across seven NIRCam broad- and medium-band (and six Hubble broadband) filters focusing on robust colors and accurate total fluxes. We measure photometric redshifts and devise a robust set of selection criteria to identify a sample of 26 galaxy candidates at z ∼ 9–16. These objects are compact with a median half-light radius of ∼0.5 kpc. We present an early estimate of the z ∼ 11 rest-frame ultraviolet (UV) luminosity function, finding that the number density of galaxies at M _UV ∼ −20 appears to evolve very little from z ∼ 9 to 11. We also find that the abundance (surface density [arcmin ^−2 ]) of our candidates exceeds nearly all theoretical predictions. We explore potential implications, including that at z > 10, star formation may be dominated by top-heavy initial mass functions, which would result in an increased ratio of UV light per unit halo mass, though a complete lack of dust attenuation and/or changing star formation physics may also play a role. While spectroscopic confirmation of these sources is urgently required, our results suggest that the deeper views to come with JWST should yield prolific samples of ultrahigh-redshift galaxies with which to further explore these conclusions.

We present a comprehensive analysis of the evolution of the morphological and structural properties of a large sample of galaxies at z = 3–9 using early James Webb Space Telescope (JWST) CEERS NIRCam observations. Our sample consists of 850 galaxies at z > 3 detected in both Hubble Space Telescope (HST)/WFC3 and CEERS JWST/NIRCam images, enabling a comparison of HST and JWST morphologies. We conduct a set of visual classifications, with each galaxy in the sample classified three times. We also measure quantitative morphologies across all NIRCam filters. We find that galaxies at z > 3 have a wide diversity of morphologies. Galaxies with disks make up 60% of galaxies at z = 3, and this fraction drops to ∼30% at z = 6–9, while galaxies with spheroids make up ∼30%–40% across the redshift range, and pure spheroids with no evidence for disks or irregular features make up ∼20%. The fraction of galaxies with irregular features is roughly constant at all redshifts (∼40%–50%), while those that are purely irregular increases from ∼12% to ∼20% at z > 4.5. We note that these are apparent fractions, as many observational effects impact the visibility of morphological features at high redshift. On average, Spheroid-only galaxies have a higher Sérsic index, smaller size, and higher axis ratio than disk or irregular galaxies. Across all redshifts, smaller spheroid and disk galaxies tend to be rounder. Overall, these trends suggest that galaxies with established disks and spheroids exist across the full redshift range of this study, and further work with large samples at higher redshift is needed to quantify when these features first formed.

We report on the host properties of five X-ray-luminous active galactic nuclei (AGN) identified at 3 < z < 5 in the first epoch of imaging from the Cosmic Evolution Early Release Science Survey. Each galaxy has been imaged with the JWST Near-Infrared Camera, which provides rest-frame optical morphologies at these redshifts. We also derive stellar masses and star formation rates for each host by fitting its spectral energy distribution using a combination of galaxy and AGN templates. We find that three of the AGN hosts have spheroidal morphologies, one is a bulge-dominated disk, and one is dominated by pointlike emission. None are found to show strong morphological disturbances that might indicate a recent interaction or merger event. When compared to a sample of mass-matched inactive galaxies, we find that the AGN hosts have morphologies that are less disturbed and more bulge-dominated. Notably, all four of the resolved hosts have rest-frame optical colors consistent with a quenched or poststarburst stellar population. The presence of AGN in passively evolving galaxies at z > 3 is significant because a rapid feedback mechanism is required in most semianalytic models and cosmological simulations to explain the growing population of massive quiescent galaxies observed at these redshifts. Our findings show that AGN can continue to inject energy into these systems after their star formation is curtailed, potentially heating their halos and preventing renewed star formation. Additional observations will be needed to determine what role this feedback may play in helping to quench these systems and/or maintain their quiescent state.

The new capabilities that JWST offers in the near- and mid-infrared (IR) are used to investigate in unprecedented detail the nature of optical/near-IR-faint, mid-IR-bright sources, with HST-dark galaxies among them. We gather JWST data from the CEERS survey in the Extended Groth Strip, jointly with HST data, and analyze spatially resolved optical-to-mid-IR spectral energy distributions to estimate photometric redshifts in two dimensions and stellar population properties on a pixel-by-pixel basis for red galaxies detected by NIRCam. We select 138 galaxies with F150W − F356W > 1.5 mag and F356W < 27.5 mag. The nature of these sources is threefold: (1) 71% are dusty star-forming galaxies (SFGs) at 2 < z < 6 with $9\lt \mathrm{log}{M}_{\star }/{M}_{\odot }\lt 11$ and a variety of specific SFRs (100 Gyr ^−1 ); (2) 18% are quiescent/dormant (i.e., subject to reignition/rejuvenation) galaxies (QGs) at 3 < z < 5, with $\mathrm{log}{M}_{\star }/{M}_{\odot }\sim 10$ and poststarburst mass-weighted ages (0.5–1.0 Gyr); and (3) 11% are strong young starbursts with indications of high equivalent width emission lines (typically, [O iii ]+H β ) at 6 < z < 7 (XELG- z 6) and $\mathrm{log}{M}_{\star }/{M}_{\odot }\sim 9.5$ . The sample is dominated by disk-like galaxies with remarkable compactness for XELG- z 6 (effective radii smaller than 0.4 kpc). Large attenuations in SFGs, 2 < A ( V ) < 5 mag, are found within 1.5 times the effective radius, approximately 2 kpc, while QGs present A ( V ) ∼ 0.2 mag. Our SED-fitting technique reproduces the expected dust emission luminosities of IR-bright and submillimeter galaxies. This study implies high levels of star formation activity between z ∼ 20 and z ∼ 10, where virtually 100% of our galaxies had already formed 10 ^8 M _⊙ , 60% had assembled 10 ^9 M _⊙ , and 10% up to 10 ^10 M _⊙ (in situ or ex situ).

We report here a high specific surface area activated carbon loaded with hemin (H-PAC) was synthesized by one-step in situ pyrolysis of paper. As the carrier of hemin, paper-derived activated carbon(PAC) showed high specific surface area (3157 m2 g-1) after optimization. The surface concentration of hemin in the material was effectively increased. Particularly, PAC had a unique interconnected porous structure, which can be used as a continuous conductive framework and provide more active sites. Hemin maintained peroxidase-like activity and showed superior synergistic effect with PAC via pyrolysis, displaying rapid redox characteristics. Under the optimized condition, the composite exhibits high electro-catalytic activities for H2O2 reduction with a low detection limit of 0.087 µM, and high selectivity. [ABSTRACT FROM AUTHOR]

As an item commonly used in daily life, filter paper could be used as a mold to easily produce sensitive, efficient, stable and commercially valuable pressure sensors. The PDMS film prepared by the filter paper mold is completely coated by SWCNTs and encapsulated by a polyethylene (PE) film to obtain a high temperature sensitivity pressure sensors (TSPS). The TSPS is sensitive between 0 Pa and 0.84 kPa pressure ranges, it is sensitivity reached at 29.94 KPa-1. The TSPS had high sensitivity for identifying low pressures (33.4 × 10-6 N), and long-lasting stability over 5,500 pressure dynamic cycles. In addition, sensors made by this method can measure temperature changes under static pressure. TSPS has good temperature sensing performance, which showed sensitivity of 0.277%/°C under 261.8 Pa pressure and 0.251%/°C under 1231.8 Pa pressure. Pressure and temperature sensors have been successfully applied to a variety of real life scenarios, which indicates that they have the potential to be applied to human life. [ABSTRACT FROM AUTHOR]

We developed new teaching materials, electrical resistors and capacitors, using carbon nanotube (CNT) paper and carbon fibre (CF) paper to foster students' creative thinking, thereby deepening and extending learning. Using a CNT-paper electrical resistor, it is possible to elucidate the dependence of the resistance value on the length and width. The resistance value is proportional to the length and inversely proportional to the width of the paper. In the case of the CF-paper capacitor, it is also possible to clarify the dependence of the capacitance value on the area and the distance between papers. The capacitance value is proportional to the areas of the papers and inversely proportional to the distance between them. Based on the results of our experiments using the new teaching materials, we confirmed that the measured values were in good agreement with the values predicted by theoretical calculations. Using these materials, it becomes possible for students to visually and actively learn about electrical resistance and capacitance through experiments by themselves and in discussion with other students, in contrast to the traditional teaching methods practiced in many schools worldwide. We found that teaching methods using these materials are a useful and easy way to teach the basic concepts of resistance and capacitance with geometric factors in classrooms. [ABSTRACT FROM AUTHOR]

High-performance electronics demand extremely sensitive piezo-resistive sensors with important features such as low-fabrication cost, easy implementation, low power consumption and high-pressure sensitivity over broad pressure range. Herein, we report a flexible piezo-resistive paper-based device functionalised by WSe2 nanosheets. An efficient and low-cost fabrication strategy using Whatman filter paper and tissue paper is adopted for versatile sensing applications. The WSe2 nanosheets were synthesized by high-yield and size-controlled liquid phase exfoliation technique. The flexible WSe2 nanosheets-paper sensor shows excellent response in broad pressure range of 1 Pa–100 kPa with exceptionally high sensitivity of 29.24 kPa−1, current responsivity of 70 and response time of 100 ms. The pressure sensor is also employed to recognize the pressure generated due to finger tapping. Encouragingly, the piezo-resistive sensors can also sense extremely small pressure differences of about 1.4 Pa generated by water drops. [ABSTRACT FROM AUTHOR]

A simple electrochemical sensor was developed by coating Onion peel wastes derived carbon nanospheres on carbon fiber paper (CFP) electrode. Carbon nanospheres (CNS) were prepared from Onion peels utilizing an environmentally benign and cost-effective strategy. In the present investigation, the obtained carbon nanospheres were coated on carbon fiber paper and the modified electrodes were physicochemically characterized by Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDS),X-ray diffraction (XRD) spectroscopy andX-ray photoelectron spectroscopy (XPS) techniques. Electrochemical characterizations of the modified electrodes were done by Cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS). CNS modified CFP electrode was successfully used in the determination of Progesterone, an important steroid hormone at an ultra-nanomolar level with superior detection limit of 0.012 nM. The developed electrochemical sensor was effectively utilized for the determination of Progesterone in pharmaceutical Progesterone injections, human blood serum samples and cow milk samples. [ABSTRACT FROM AUTHOR]

In recent years, due to the development of biomass materials and their lowcost, renewable and environmentally friendly characteristics, the use of electrochemical processes to treat wastewater is considered to be a very attractive solution. The use of discarded corrugated paper to prepare high value corrugated paper activated carbon (CPAC) cathodes degrades phenol in wastewater by electrochemical advanced oxidation processes (EAOPs). The degradation efficiency in 120 min can reach 93.76%. CPAC can also be used in the field of supercapacitors. In a three-electrode system using 6MKOH as the electrolyte, the specific capacitance is as high as 415.66 F g-1 at the current density of 1 A g-1. When the current density is 10 A g-1, the specific capacitance can reach 310 F g-1. Furthermore, after 5000 cycles of charging and discharging, the capacitance retention rate was 89.99%. It can be seen that CPAC is a dual-functional material suitable for both electrocatalytic degradation and supercapacitors. [ABSTRACT FROM AUTHOR]

Carbon paper is one of the most common carbon electrode materials employed in electrochemical research due to its low cost, disposability, and controllable dimensions and scaling. Carbon paper is usually hand cut and a variety of strategies are used to define electrode area. This procedure is tedious, imprecise, and inaccurate, yielding coefficients of variation in peak current output as high as 20%. Imprecision in hand-preparation translates directly to poor reproducibility in electrochemical data leading to challenges in directly comparing data across research groups and research fields. This work introduces an inexpensive and precise method to automatically cut and rapidly wax carbon paper electrodes, circumventing laborious traditional preparation and substantially improving precision in electrochemical data.

With the development of printed electronics technology, the demand for printed conductive inks had also put forward higher standards. The shortcomings of traditional printed circuit boards, such as complex technology, consumables, and pollution, had also been resolved with the development of 3D printing technology. In this paper, low-content silver nanoparticles were blended with graphene alcohol slurry and dissolved in a non-polluting solvent such as absolute ethanol. The synergistic effect of the composite of the hexagonal structure of the graphene sheet and the silver nanoparticles improved the ink’s performance of electrical conductivity, adding water-based polyurethane/acrylic resin system to improve the adhesion between ink and paper. The conductive ink can be used to 3D print circuit circuits on paper. After drying, the resistance was measured. After the battery, diode, and switch were connected, a circuit diagram was made. After pressing the diode emits was lighted. This work is expected to be applied to flexible circuit boards to provide basic research.

A facile electrochemical sensor based on Ruthenium-Phosphate (Ru-Pi) was developed by electrodeposition of Ru-Pi on Polypyrrole (PPy) modified carbon fiber paper (CFP) electrode. Phosphate buffer solutions of neutral pH containing RuCl3 was used for voltammetric deposition of Ru-Pi on PPy/CFP electrode. The modified electrodes were characterized by High resolution transmission electron microscopy (HRTEM), High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and electroanalytical techniques. A significant amount of phosphate (Pi) and Ru centers in higher oxidation states were present on Ru-Pi film deposited on PPy/CFP substrate. Pi plays a significant role during catalyst deposition and in its activity toward determination of Cholesterol. DPV studies demonstrated that under optimum conditions, the developed sensor has displayed a wide linear dynamic range between 0.16 nM and 20.0 nM with a superior detection limit of 0.54 × 10-10 M. The proposed method was effectively applied in the nonenzymatic determination of cholesterol at an ultralow level in human blood serum samples. The method displayed high selectivity toward cholesterol in the presence of other interfering substances. [ABSTRACT FROM AUTHOR]

We report a type of transition metal selenide (Fe40Co40Se20) thin films supported on carbon fiber paper (CFP) (Fe40Co40Se20/CFP) and study the effects of the substrate temperature during thin film deposition on the electrocatalytic performance of the films in the oxygen evolution reaction. Fe40Co40Se20/CFP thin films were deposited by vacuum magnetron sputtering at substrate temperatures of 308, 393, and 573 K. In 1MKOH, the amorphous film deposited at 393 K exhibited better comprehensive electrocatalytic activity and stability than that of the Fe40Co40Se20/CFP thin films deposited under other conditions, achieving a low overpotential of 307 mV at a current density of 10mAcm-2 and low Tafel slope of 35mVdec-1. These results reveal that an appropriate substrate temperature during film formation improves the catalytic performance of thin film catalysts to some extent. A combination of lowcharge resistance and large electrochemically active surface area contributes to the electrocatalytic performance of the Fe40Co40Se20/CFP thin films. [ABSTRACT FROM AUTHOR]

The side reactions during long-term operation of vanadium redox flow batteries (VRFBs) increase the average oxidation state of the electrolyte and associated equilibrium potential of the positive half-cell. This consequently initiates the corrosion reactions at the positive side as the half-cell potential passes the critical limit. In this study, an ex-situ accelerated electrochemical corrosion protocol is performed on the carbon paper electrode to investigate the effects of corrosion conditions induced by extended cycling on electrode morphology and VRFB system performance. In terms of morphological changes of corroded electrodes, only minor mechanical degradation is observed, including disappearance of binder material and reduced mechanical properties. With regards to the cell performance, the flow cell with the corroded electrode demonstrates notably higher charge and discharge capacities which can be attributed to the enhanced active surface area of the electrode. Furthermore, the corroded case exhibits an improved capacity retention during extended cycling which can be related to the improved redox activity caused by the increased carboxyl groups and wettability. This study shows that even at these fairly aggressive corrosion conditions, the process behaves as a treatment method, which oxidizes surface functional groups, increases active surface area, and hydrophilicity, and subsequently enhances VRFB performance. [ABSTRACT FROM AUTHOR]