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As one of the most promising energy-storage devices, supercapacitors have drawn great research interests because of their outstanding electrochemical behavior. Carbon paper holds great prospect as an electrode material for supercapacitors since it is inexpensive and highly conductive. In this paper, the modified Hummer's method is employed as an effective strategy to produce activated carbon paper with rougher surfaces and increased specific surface areas. It is further observed that hydrophilic groups such as hydroxyl (-OH), carbonyl (>C=O), and carboxyl (-COOH) have been introduced into the surface of carbon paper over treatment and they serve as strong polar sites to absorb water molecules, leading to improved hydrophilicity. Thus, the as-treated carbon papers with both increased specific surface areas and improved surface hydrophilicity exhibited excellent capacitive characteristics. Moreover, the charge/discharge test over 2000 cycles shows their excellent long-term capacitive retention. [ABSTRACT FROM AUTHOR]

Smoothness is an important factor in consumer perception of tissue quality, with physical modification and chemical additions to the paper able to enhance tissue handle. Therefore objective measurement of the papers mechanical properties in developing new products and maintaining existing quality is vital. In this study the surface chemical composition of the softener treated paper is investigated using ToF-SIMS, and related to the surface frictional properties of the paper. [ABSTRACT FROM AUTHOR]

Flexible graphene-based paper is promising for wide applications due to its outstanding electrical and thermal conductivities. Graphene flakes with large size are usually known as the key factor for improved paper performance. However, we find that a combination of flakes with large and small sizes is more favorable for both electrical and thermal conductivities than pure large flakes. In this work, flexible paper with enhanced electrical and thermal properties was fabricated by mixing graphene flakes with various size distributions. Large-size graphene (LSG) flakes play the role of a backbone structure, whereas small-size graphene (SSG) flakes fill the voids in the paper without disturbing the high orientation. The physical properties of the as-prepared graphene papers with contents of SSG varying from 0 to 100% have been investigated. It is found that the electrical and thermal conductivities of the paper with 25 wt% SSG are both around 140% higher than that of pure LSG paper. Our results indicate that the lightweight and flexible graphene-based paper has great potential for lateral heat dissipation applications requiring heat movement in a particular direction. [ABSTRACT FROM AUTHOR]

The effects of two kinds of wastewater (black liquor and paper regeneration wastewater) from paper industry as solvent on the hydrothermal liquefaction of plantation biomass were discussed in this study. For the solvent of eucalyptus, black liquor was not suitable because the oil yield was very low and the yield of water-soluble constituent was very high. There was little difference in the product yields between the liquefaction of eucalyptus with the paper regeneration wastewater (pH 9.5) and that with NaOH aqueous solution (pH 9.5). In comparison with the liquefaction with water, the decrease of residue yield and the increase of oil yield were observed on the liquefaction with the wastewater. During the liquefaction with water, it was anticipated that dehydration and polymerization between carboxylic and phenolic hydroxyl groups in the molecules of the eucalyptus occurred. On the other hand, carboxylic acid formed during the liquefaction of eucalyptus was considered to be neutralized with Na+ in NaOH aqueous solution or cations in the wastewater because the formation of carboxylate was observed in the water-soluble constituents derived from these liquefactions. Therefore, the residue yield decreased owing to the inhibition of the condensation reaction. Accordingly, possibility for the reduction of the amount of greenhouse gas (CO2) and paper regeneration wastewater, and the production of oil from eucalyptus was clarified on the liquefaction of plantation biomass (eucalyptus) with paper regeneration wastewater. [ABSTRACT FROM AUTHOR]

new type of paper with superhydrophobic surface was prepared by addition of modified nano-TiO to cellulose pulp. Nano-TiO powder was first dispersed with a high-speed homogenizer, followed by surface modification with the coupling agent, 3-(trimethoxysilyl) propyl methacrylate (MPS). The superhydrophobic and opaque paper was obtained by adding the modified nano-TiO to plant fiber to change its characteristics from hydrophilic to hydrophobic. The effects of the initial content of the coupling agent MPS used, on the weight percentage of MPS attached on the surface of nano-TiO were studied. The obtained paper was characterized by contact angle measurements and SEM. The results showed that the water contact angles for the modified paper ranged from 126.5 to 154.2°, and the sliding angle was <3°. Moreover, many well-dispersed nano-TiO protuberances were observed on the surface of the paper, which further confirmed that the obtained paper was superhydrophobic on account of its nanostructure. Comparative optical studies performed on the paper handsheets revealed a much higher opacity for the sample with the MPS-modified-TiO nanoparticles. [ABSTRACT FROM AUTHOR]

Cellulose insulation paper as a part of oil-paper insulation systems plays an important role in the reliability of converter transformers. The reliability of converter transformers equipped with traditional cellulose paper is adversely affected by space charge under DC voltage. The addition of nanoparticles into other dielectrics has been demonstrated to improve electrical performance. However, studies on the space charge behavior of cellulose paper reinforced with nanoparticles are rarely reported. This paper presents the results of a study aimed at elucidating the effect of nano-aluminum nitride (AlN) concentration on the space charge behavior of cellulose paper. Samples with various nano-AlN concentrations were fabricated and pretreated first. The micro-morphologies of prepared cellulose papers were observed using a field-emission scanning electron microscope. The space charge distribution was measured using a pulsed electroacoustic instrument. The results show the dependence of the charge injection as well as charge dissipation on the concentration of nano-AlN. The isothermal decay current method is used to obtain trap information. Based on the density and distribution of traps, the underlying mechanism of the effect of various concentrations on the space charge behavior is theoretically explained. [ABSTRACT FROM AUTHOR]

The hydrogel in this paper is designed to do just that, by using controlled release from a hydrogel to deliver the drug quickly and at a relatively high concentration to the interior of cancer cells. The paper describes the synthesis and in-vitro testing of a hydrogel composite that is designed to maximize toxicity to cancer cells by both efficiently delivering the cancer drug doxorubicin (DOX) and overheating the cells with magnetically induced hyperthermia. This makes it highly desirable to develop a delivery system that can encapsulate the drug, bring the drug directly to the cancer cells then release the drug into the cancer tumor or cells. [Extracted from the article]

Professor Grimes summarizes the winning paper and the two runners-up:"Machine learning is certainly of great current interest to address the multivariable materials design challenge. 10.1007/s10853-022-07499-9 5 Wang Z, Lai A, Schuh CA, Radovitzky R. Phase transformation and incompatibility at grain boundaries in zirconia-based shape memory ceramics: a micromechanics-based simulation study. The winner of the 2022 Robert W. Cahn Best Paper award is "Machine learning guided alloy design of high-temperature NiTiHf shape memory alloys" by Udesh M.H.U. Kankanamge, Johannes Reiner, Xingjun Ma, Santiago Corujeira Gallo, and Wei Xu. [Extracted from the article]

The ability of the bacteria Gluconacetobacter sucrofermentans to produce high-quality cellulose is well known. This bacterial cellulose has unique properties, as the result of an ultrathin crosslinked structure. It is almost chemically pure (until 98% cellulose), has a high crystallinity, mechanical strength, elasticity and durability. It is compatible with plant cellulose and could be grown on a vegetal fibrous network what makes bacterial cellulose an excellent candidate to reinforce damaged papers. The objective of this work is to promote the production of bacterial cellulose on the surface of a variety of papers by the direct application of a culture of G. sucrofermentans and to test if this procedure could be an economic and feasible possibility in reinforcing papers or cellulosic surfaces. After 7 days of cultivation, G. sucrofermentans deposits a thin layer (ca. 10 µm) of bacterial cellulose on the papers surfaces. Microscopic observations have shown a heterogeneous covering of the surfaces, while the modified papers maintain their thickness and their basic weight. The treatment has not increased the papers mechanical properties, but maintains them after artificial aging. The changes in optical properties of the reinforced papers, such as opacity and colorimetric coordinates, are minor even after further aging. Air permeance is the paper characteristic that experiences more variations because the layers of bacterial cellulose inhibit the airflow through the papers. The changes in the static and dynamic contact angles suggest that the bacterial cellulose structure is more compact and make the surface more hydrophobic than the original paper surface. [ABSTRACT FROM AUTHOR]

We present a theory giving the standard roughness metrics R a and R q of stochastic fibrous materials in terms of their porosity and the thickness of the constituent fibres. Our treatment shows also that R a and R q are linearly dependent on each other with gradient depending on the skewness of the surface depth profile. Comparison of our theory with experiments on laboratory-formed paper samples and with data from the literature for industrially manufactured paper and carbon fibre nonwovens for use in fuel cells is excellent. The theory has applicability to generic families of stochastic fibrous materials and has relevance, for example, to printing of devices on paper. [ABSTRACT FROM AUTHOR]

As the development of dual-ion batteries (DIBs) is limited by the capacity of anions intercalation, we put forward an innovative design idea of DIB. Compared with the traditional graphite cathodes, few-layered reduced graphene oxide (rGO) has a large specific surface area and can greatly improve the utilization ratio of carbon layers for fast redox reaction process. In addition, the carbon paper current collector with porous network structure facilitates the uniform distribution of active materials, rapid penetration of electrolyte and fast migration of ions, and also relieves the volume strain caused by PF6− intercalation/de-intercalation. Under the effects of the above two aspects, the lithium-rGO DIB demonstrates significantly enhanced electrochemical performance compared with conventional DIBs. It possesses an ultra-high discharge capacity of 405 mA h g−1 with a coulombic efficiency of > 98% after 1000 cycles at 1 A g−1 in the voltage range of 3.0–5.0 V. The detailed mechanism of electrochemical performance enhancement is also discussed. [ABSTRACT FROM AUTHOR]

A facile and cost-effective modified sol–gel synthesis is employed to synthesize flexible silica-cellulose hybrid aerogels (SCHA) using recycled cellulose fibers (RCF). The effect of cellulose fiber concentrations and ambient temperature conditions on the thermal, acoustic, and oil absorption characteristics was quantified comprehensively. The experiments were conducted by considering the range of weight fractions from 1–4 wt.% from waste tissue paper with a cross-linker and tetraethylorthosilicate (TEOS) as silica precursors. The SCHA aerogels were modified by a silylating agent with surface hydroxyl groups to achieve superhydrophobic behavior with a water contact angle (WCA) as high as 168°. The synthesized aerogels were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), scanning electron microscope (SEM), and Brunauer-Emmett-Test (BET) to identify the physical morphology. An excellent oil absorption capacity of 24.8 g.g−1 was also noticed with 4 wt.% of cellulose concentration in hybrid aerogel retained up to 5 cycles with an absorption capacity of 6.4 g.g−1. The average thermal conductivity of hybrid aerogels was estimated in the range of 0.038–0.032 W/m K. Slight enhancement in the thermal conductivity is noted with the increase in wt.% of cellulose to the silica aerogel. However, about 40–50 °C improvement in thermal degradability (as concluded from Thermogravimetric Analysis) with a minimum weight loss was observed in hybrid aerogel over cellulose aerogel. A comparatively high sound absorption coefficient of 0.453–0.628 at low frequency (1500 Hz) and 0.86–0.94 at high frequency (3600 Hz) was achieved with an average thickness of 8 mm compared to cellulose aerogel. The compressive Young's modulus of hybrid aerogels was also enhanced by 94.12%. [ABSTRACT FROM AUTHOR]

Paper is a widely used packaging material and is nowadays regaining importance, e.g., as bio-based and biodegradable material. Moreover, new technologies such as polymer-fiber composites, printed electronics and the deep drawing of paper are developing. The process stability and also the resulting quality of paper converting processes such as coating, metallization, printing, and the printing of electronics are highly affected by the hygroexpansion of paper. In order to reduce production instability and to choose and develop paper substrates with ideal characteristics, critical parameters need to be known. This paper offers an extensive overview of those parameters, starting at a molecular and microscopic level with the effect of the constituents and morphology of single fibers, before moving on to paper contents, chemical modifications and additives and finally concluding with paper production and fiber network modification. It was found that the major influences are single fiber sorption, inter-fiber contacts, microfibril angle, fiber morphology (length, width, curliness) and fiber orientation. This review gives new ideas and insights for technologists working in research, development and production optimization of paper-based products. [ABSTRACT FROM AUTHOR]

Of course, the paper complements the SEM imaging, which is intrinsic to the FIB, with imaging and diffraction in the TEM. The paper does also have a SharedIt link like all articles in JMS (https://rdcu.be/cWW0L) so it can be widely and immediately shared with readers; all papers published in JMS are free-to-read using the SharedIt link from the moment they appear online with their permanent DOI. The cover for the November 2022 issues of the Journal of Materials Science comes from the paper by Tunes et al. which appeared in issue #35 from September 2022 [[1]]. [Extracted from the article]

Facile and robust immobilization of metal nanoparticles onto porous supporting matrix is an important issue in heterogeneous catalysis. This study reports a facile procedure for the synthesis and immobilization of small catalytic active silver nanoparticles (AgNPs) on cellulose paper (CP), which possesses interconnected fibrous structure and can be employed as cost-effective supports. Amino groups were first introduced to CP, through a silane coupling technique, to provide stable anchoring centers for silver ions. Small-sized AgNPs without aggregation were facilely synthesized and stably immobilized onto the fiber surface of CP followed by NaBH reduction. The as-prepared AgNPs incorporating composites exhibited excellent catalytic activity for the reduction of 4-nitrophenol. The rate constant of the catalytic reaction was calculated to be 1.46 × 10 s. More importantly, these amino-modified paper-based composite catalysts can be easily recovered and reused for at least six cycles due to their enhanced mechanical and catalytic stability. [ABSTRACT FROM AUTHOR]

We present theory for the shrinkage on drying of the cross-sectional area of cellulosic fibres and show that this depends on their initial moisture content only. For the linear shrinkage of cross-sectional dimensions, an additional parameter is required, which we estimate from comparison of the theory with experimental data from the literature. We proceed to combine our model of fibre shrinkage with probabilistic theory for fibre contacts in random fibrous networks to obtain a model for the unrestrained shrinkage of isotropic paper sheets. The expression obtained depends only on the moisture content of fibres and the extent of inter-fibre contact and exhibits good agreement with experimental data for laboratory-formed paper sheets. The results have relevance to the commercial manufacture of paper and potential for application to the study of cellulose nano-composites. [ABSTRACT FROM AUTHOR]