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Pineapple leaf fibers (PALF) were biopulped using Trametes versicolor, and the resulting biopulp was bleached with xylanase-enzymatic treatments. The biopulping was extensively described using determinations of fiber morphology, color, chemical composition, extractive content, and thermal stability using the structural characteristics determined by XRD and paper properties. The results showed that the chemical and enzymatic treatments shortened the fiber, almost to 50%, and the Kappa index decreased from 27 to 13. Cellulose and holocellulose contents increased from 65% to 74% and from 86% to 91%, respectively, but extractives, lignin (from 12% to 4%), pentosans (from 25% to 14%) and the crystallinity decreased from 58% to 67% in both chemical bleaching and further xylanase-enzymatic processing. Xylanase)enzymatic processing allowed us to obtain whiter (increased lightness color and decreased redness and yellowness tonality) and heavier paper, even though it presented decreased mechanical properties (decreased stress resistance, rupture length, tear resistance and index longitudinal tearing). The xylanase-enzymatic treatment with the best pulping and paper proper)ties is when the biopulp is treated with a xylanase enzyme concentration of 0.04% (w/w). [ABSTRACT FROM AUTHOR]

Banana stem is a known alternative to wood for the production of pulp and paper. During the production of paper, it is extremely important to save costs and time while at the same time enhancing quality of produced paper. In the present study, paper was developed from banana stem fiber by optimizing its density. Response surface methodology (RSM) using Box-Behnken design (BBD) was used to determine optimum blending parameters of the developed papers. The influence of banana stem fiber amount (250-1000 g), water amount (1-2liters) and blending time (5-10 min) on paper density was ana)lyzed using software Stat-Ease 360, Version 13. The optimum conditions of banana stem fiber amount, water amount and blending time to achieve a density of 675.75 g/m3 were determined as 461.83 g, 1.31liters, and 8.53 min, respectively. ANOVA results revealed that the quadratic model best fits the density response, with blending time and banana stem fiber amount as the most significant model terms. Linear effects were more predominant than quadratic and interaction effects. The developed density model was in close agreement with experimental findings with an R² value of 0.9748. Developed paper had cellulosic contents, with volatiles as high as 82.11%wb and 2.11% wb ash composition. Future works on thermal properties of paper are encouraged. [ABSTRACT FROM AUTHOR]

High-performance air filters composed of a hybrid structure of nanofiber/microfiber were fabricated using wet paper processing. Two types of nanofibers (NF) with average diameters of 180 and 234 nm were mixed with a suspension of microfibers (11.5 and 11.7 µm) in various mixing fractions. Then, the suspension was filtered to fabricate hybridized fiber sheets with a known nanofiber/microfiber composition. The effects of NF diameter and mixing fraction on the performance of the hybrid filters were experimentally investigated. With increasing NF fraction, both the particle collection efficiency and the pressure drop increased. The quality factor (Qf) was used to evaluate the performance of the prepared filters. As predicted by the single fiber filtration theory, the experimentally obtained Qf was almost independent of the mixing fraction of the NF. The collection efficiency and pressure drop of the hybrid filters could be controlled by the NF fraction at the same Qf. Moreover, the inhomogeneity factor of fiber packing (δ) did not significantly affect Qf over the δ range from 3 to 23 for our filters. This implies that the lower particle capturing efficiency due to heterogeneous packing could be compensated by a decrease in the pressure drop, resulting in the same Qf value. Therefore, Qf for particles smaller than 100 nm, which are in the diffusion-controlled regime, can be increased by reducing the NF diameter. Copyright © 2019 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed. [ABSTRACT FROM AUTHOR]

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed [ABSTRACT FROM AUTHOR]

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed. [ABSTRACT FROM AUTHOR]

The article presents a reprint of the article "Mathematical Games," by Martin Gardner, which appeared in the December 1956 issue of "Scientific American." It focuses on flexagons, their history before World War II, and how to create several hexaflexagons. It mentions that flexagons are folded paper polygons from crooked or straight paper strips.

Zinc oxide (ZnO) nanorods were grown on a paper support prepared from soft wood pulp. The photocatalytic activity of a sheet of paper with ZnO nanorods embedded in its porous matrix has been studied. ZnO nanorods were firmly attached to cellulose fibers and the photocatalytic paper samples were reused several times with nominal decrease in efficiency. Photodegradation of up to 93% was observed for methylene blue in the presence of paper filled with ZnO nanorods upon irradiation with visible light at 963Wm-2 for 120 min. Under similar conditions, photodegradation of approximately 35% was observed for methyl orange. Antibacterial tests revealed that the photocatalytic paper inhibits the growth of Escherichia coli under room lighting conditions. [ABSTRACT FROM AUTHOR]

This article is a preliminary attempt to understand the corporate social responsibility claims and impacts of Aracruz Celulose sa, Brazil's largest pulp and paper manufacturer. Aracruz locates its operations in the vulnerable biodiversity hotspot of the Atlantic Forest, having acquired 800 000 hectares of land in five states of Brazil for the planting of eucalyptus. It owns some of the largest pulp and paper mills in the country. Both its record of land acquisition and its impact on the environment have resulted in considerable social conflict with the indigenous inhabitants, former slave communities and other small farmers in the state of Espírito Santo, and with supportive activist ngos. The company's application of formal corporate social responsibility practices often flies in the face of its social and environmental impacts. This raises questions about the nature of corporate social responsibility and its claims in developing countries like Brazil and elsewhere. [ABSTRACT FROM AUTHOR]

Focuses on the indeterminate art of Alison Knowles. Comparison between the 1962 and the 2003 versions of her "Make A Salad" piece; Artistic factor which differentiates Knowles from her male peers; Information on her Bean Turner series which uses paper and beans.

Radiographic images of paper are used to study the watermarks and the pattern of chain and laid lines originating from the sieve used in the production of the paper. X-rays with low penetrative power are used to obtain images with sufficient contrast as a result of differences in thickness/density of the paper. This article explains the improvement in contrast which can he obtained by lowering the X-ray tube potential, which reduces the penetrative power of the beam. Lowering the tube potential is limited by the attenuation of the radiation in air, which ultimately becomes so strong that exposure times become Unacceptably long. By replacing the air with helium, this attenuation of the X-ray beam can be reduced. A container for helium was developed which had an airtight fit to the exit window of the X-ray tube and has an exit window of a very thin layer of polyethylene. The effect of the technique was investigated by measuring the first and second half value layer (HVL) the beam expressed in millimetres of high density polyethylene (HDPE). [ABSTRACT FROM AUTHOR]

The rusty-red, irregularly shaped areas known as foxing or fox spots are prevalent on rag paper used in books from the sixteenth to the nineteenth century. Foxing may vary in size from just visible spots to large areas covering most of a page, and in some cases the stain migrates through successive pages. The present study investigated the role of fungi in foxing, and the location and cause of the discoloration in these spots. Using light microscopy and staining with aqueous aniline blue, it was observed that the initial cause of the foxing was a group of separated conidia (spores) which had been deposited on the surface of the paper prior to printing and had germinated in situ during the slow drying of the paper. The colour in the foxed areas is due to an alkaline-soluble rusty-red material and an insoluble straw-coloured stain in the paper fibres. Observations of migrated stains support the theory that fox spots are part of three-dimensional stain structures which are generated in stacks of paper either during the manufacturing process or after binding. Papermakers' felts are suggested as the source of contamination, and autoxidation of lipids from the conidia is a possible cause of the discoloration of the fungal material and paper fibres. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide is a common air pollutant, formed in the atmosphere from the nitric oxide emissions from fuel combustion sources. Samples of organic and inorganic pigments, iron inks on paper, and traditional Japanese textile dyes mordanted Onto silk were exposed to 0·50ppm NO2 in air for 12 weeks. Ten of the traditional natural organic colorant samples on paper tested showed measurable color changes (ΔE > 2) as a result of the NO2 exposure, as did several of the anthraquinone-based synthetic organic pigments. The arsenic sulfide pigments orpiment and realgar and the iron inks tested showed considerable color changes (ΔE > 5) over the 12-week period. Nine of the 23 Japanese dyed silk cloths changed color by at least two ΔE units, including an enju sample (derived from the Japanese pagoda tree) that faded by more than seven ΔE units An NO2 dose (concentration times duration of exposure) of the magnitude employed in this experiment would be experienced inside an unprotected museum in downtown Los Angeles over about a two-year period, and in many other cities within a period of five to six years. [ABSTRACT FROM AUTHOR]

The colorfastness of several traditional Japanese colorants upon exposure to atmospheric ozone was tested in a chamber exposure experiment. Samples, in the form of colorants applied to paper, dyes on silk cloth, and colorants on a nineteenth- century Japanese woodblock print, were exposed to an atmosphere containing 0·40 parts per million ozone at 22°C and 50% RH, in the absence of light, for 12 weeks. Color differences, calculated from the measured diffuse reflectance spectra, were used to assess the rate and extent of the ozone fading. Of the colorants applied to paper, orpiment was the only inorganic pigment that showed severe color loss after ozone exposure. Several organic colorants on paper also reacted, including the widely used plant colorants ai (indigo) and ukon (turmeric). The woodblock print, produced using the plant-derived colorants beni (safflower), ai (indigo), shiō (gamboge) and aigami (dayflower), showed significant ozone fading only in the blue and green areas, which contain ai. Several of the dyed silk cloths also exhibited some color change in this experiment, suggesting that prolonged exposure to atmospheric ozone could pose a risk to these materials as well. [ABSTRACT FROM AUTHOR]

The long-term effect of gamma irradiation on paper was studied. Three types of paper (pure rag, mixed rag and mechanically prepared woodpulp) were subjected to three treatments: gamma irradiation, accelerated dry aging, and radiation followed by aging. The effects of these treatments on the physical properties of the paper samples were assessed by measuring alterations in mechanical strength as determined by changes in folding endurance and tear resistance when compared to the untreated control samples. It was found that gamma irradiation caused a decrease in the mechanical strength of the papers similar to that resulting from accelerated dry aging. A synergistic effect was found when both irradiation and accelerated aging were performed on the paper samples, demonstrated by an even greater decrease in both fold endurance and tear resistance than that resulting from either gamma irradiation or accelerated dry aging alone. [ABSTRACT FROM AUTHOR]

Framed and glazed prints have been found to yellow rapidly when on exhibition. It was found that the frames all contained the fungicide thymol. Experimental work has shown that the discoloration is caused by photoxidation. The discoloration was present in the paper and in the polymethyl methacrylate glazing. Mass spectroscopy has revealed the presence of a polymer of thymol; there was no evidence for the expected oxidation products. [ABSTRACT FROM AUTHOR]

The author reacts to comments made to his article. Perhaps Professor C. Roseman has overstated his case a bit when he asserts that three aspects of the author's paper may have been "quite misleading." Perhaps Roseman's concern about the theory of stepwise regression may be valid, but the author is happy to be able to set his mind at ease about the real world evidence with which he dealt. Perhaps Roseman has fallen into the beguiling trap of confusing statistical association with cause-and-effect explanation. Certainly population continued to increase in many resort areas during the 1970s, but one must entertain serious doubts about anyone who tries to ex- plain population increase by counting the number of empty houses.

The author reflects on which high-value commodity could be put forward for the 100th Jubilee spot in the U.S. as of July 2012. He believes the link between an anniversary and the particular commodity associated with it could be proportional to the item's value, such as paper, cotton and leather celebrating the first five years. He is proposing oil, which has reached a price of around 100 U.S. dollars per barrel (bbl), to have that 100th Jubilee spot.

Provides an introduction to this issue of the 'International Journal of Transgenderism'; Collection of papers presented at the 'What is Trans/Gender?' Symposium in 1999; The author's vision for a true symposium that included discussion; View that the collection of papers offers a well-rounded, interdisciplinary look at the concepts of both gender and transgender.