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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).

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]

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]

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]

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]

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.

As a key component of electronic skins, flexible pressure sensors have attracted more and more attention because of the increasingly growing demand. Stability is a key parameter to evaluate pressure sensors, while relatively few reports have focused on it. Here, a paper-based piezoresistive sensor is developed, in which, the airlaid paper based sensing layer is modified with silver nanowires (AgNWs) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and sandwiched in between two convex electrodes. Due to the cross bonding of PEDOT:PSS membrane, the conductive paths of AgNWs networks are strengthened and stabilized, thus the stability of the sensor is found to be significantly improved. Besides, to regulate the compressibility by varying sensing layers, the performance of the proposed sensor can be further improved, and its practical application performances in healthcare pulse monitoring, tiny muscle motion, and voice recognition are demonstrated. The results confirm that PEDOT:PSS has the potential as stabilization media to AgNWs for paper-based flexible wearable electronics. [ABSTRACT FROM AUTHOR]

Intraoperative electron radiotherapy (IOERT), which is an accelerated partial breast irradiation method, has been used for early-stage breast cancer treatment. In IOERT, a protective disk is inserted behind the target volume to minimize the dose received by normal tissues. However, to use such a disk, the surgical incision must be larger than the field size because the disk is manufactured from stiff and unyielding materials. In this study, the applicability of newly developed tungsten-based functional paper (TFP) was assessed as an alternative to the existing protective disk. The radiation-shielding performance of the TFP was verified through experimental measurements and Monte Carlo simulations. Percentage depth dose curves and lateral dose profiles with and without TFPs were measured and simulated on a dedicated IOERT accelerator. The number of piled-up TFPs was changed from 1 to 40. In the experimental measurements, the relative doses at the exit plane of the TFPs for 9 MeV were 42.7%, 9.2%, 0.2%, and 0.1% with 10, 20, 30, and 40 TFPs, respectively, whereas those for 12 MeV were 63.6%, 27.1%, 8.6%, and 0.2% with 10, 20, 30, and 40 TFPs, respectively. Slight dose enhancements caused by backscatter radiation from the TFPs were observed at the entrance plane of the TFPs at both beam energies. The results of the Monte Carlo simulation indicated the same tendency as the experimental measurements. Based on the experimental and simulated results, the radiation-shielding performances of 30 TFPs for 9 MeV and 40 TFPs for 12 MeV were confirmed to be acceptable and close to those of the existing protective disk. The findings of this study suggest the feasibility of using TFPs as flexible chest wall protectors in IOERT for breast cancer treatment.

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]

In this paper, a simple method for preparing high stability superhydrophobic paper with pH-induced wettability transition was proposed. Firstly, the pH-responsive monomer 2- (dimethylamino) ethyl methacrylate (DMAEMA), the silicon-containing crosslinking monomer 3-trimethoxysilyl propyl methacrylate (TSPM) and the fluorine-containing monomer hexafluorobutyl methacrylate (HFMA) were polymerized to prepare the pH-responsive polymer PHFMA-PTSPM-PDMAEMA. Afterwards, the amino-modified SiO _2 was grafted onto the polymer to provide roughness and then coated on the paper to prepare the superhydrophobic paper with pH-responsive properties. Further research found that the modified paper prepared by this method not only has strong stability and transparency, but also can realize the reversible regulation of superhydrophobic & lipophilic and super-oleophobic & hydrophilic properties under different pH-induction, and it has important application value in the field of oil-water separation in industrial applications.

Low concentration of biomarkers (proteins, nucleic acids, metabolites) is a major concern in early disease diagnosis due to the very low concentration of these biomarkers at the early stage of any disease. This challenge can be addressed by preconcentrating the biomarkers to improve the sensitivity of the diagnostic device. This paper describes a novel method to preconcentrate the charged molecules on paper using greenly synthesized iron nanoparticles. The iron nanoparticles were synthesized by utilizing plant extract as stabilizing agent, which both minimizes the cost and protects the environment. Three different samples of the nanoparticles were prepared by changing the charge or attaching a functional group (amine) to the surface. The iron nanoparticles act as a charged nanoporous membrane when deposited on the paper pads inducing electrostatic forces around the membrane leading to the concentration of the charged analytes near the boundary of the membrane. Crystal violet was used as a surrogate for the charged biomolecule. We report ∼24-fold increase in the concentration of crystal violet dye within 120 seconds using the positively charged membrane and the 0.2 mM dye solution. The developed experimental set-up eliminates the need for external pumping device and complex fabrication processes making the proposed method cost-effective, environment-friendly, and simple to use.

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]

With the utilization of used newspaper into the paper making industry, bleaching has been an area of concern to obtain a balance between desired brightness and the amount of treatment it requires. Motivation of this study was to optimize bleaching of recycled newsprint fibers in terms of five variables namely hydrogen peroxide charge, amount of sodium hydroxide employed, pulp consistency, bleaching temperature, and bleaching time. Experimental work was conducted in the laboratory to simulate bleaching plant and it was found that higher peroxide charge is better for improvement in brightness, but it is uneconomical to increase peroxide charge indefinitely. The amount of hydrogen peroxide is added so that the residual peroxide at the end of the reaction is not less than 10% of the initially added peroxide. Sodium hydroxide provides alkalinity which is very important for making the fibers flexible and softening of ink particles but it also contributes to pulp yellowing if residual hydrogen peroxide contents are lesser than the minimum required value. So, for 16 kg t ^−1 of hydrogen peroxide, 6 kg t ^−1 of sodium hydroxide prevented the brightness reversion in this study. Higher pulp consistency is better but unavailability of very high consistency pulp mixer in the industry is a limiting factor for higher than 30% pulp consistency. Temperature and time are quite interrelated and, with the given bleaching conditions, a temperature of 95 °C with 10 min residence time was found to be optimum for this study. It was also observed that multiple pre-washings increase brightness and save bleaching chemicals.

In this study, hexafluorobutyl methacrylate (HFMA) and 3-trimethoxysilyl propyl methacrylate (TSPM) were used for polymerization. First, the one-step method is used to prepare a hydrophobic polymer with low surface energy (PHFMA-PTSPM), and then the amino groups on the modified silica surface are used to graft nanoparticles on the polymer to improve the roughness, thereby a new type of high stable super hydrophobic paper was prepared. The further study found that the paper after superhydrophobic treatment has strong hydrophobicity, and its water contact angle reached 156°± 1.6°. In addition, the coating on the surface of the paper after superhydrophobic modification has high transparency, and the effect of the superhydrophobic coating on the color of the paper is within the acceptable range of human eye recognition. Moreover, the modified paper not only has good weather resistance and folding resistance, but also has strong corrosion resistance to strong acids, strong alkalis and organic solvents.