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Water hyacinth (Eichhornia crasspies) was used as a renewable cellulose source to prepare nanofibrillated cellulose (NFC). Due to the porous structure and low lignin content of water hyacinth, a 10 min-treatment time using the high-speed homogenization was sufficient to disintegrate nanofibers. The average width of the NFC treated for 40 min was 16.8 nm. With longer treatment times, a slight decrease in thermal stability of NFC was found while no changes in the crystallinity index of NFC were detected. Moreover, paper was formed from NFC with respect to mechanical treatment times. Results showed NFC treated with longer treatment times could prepare the paper with lower pore sizes between adjacent fibrils and porosity, resulting in higher wettability and mechanical properties. The contact angle of the 40 min-treated NFC paper was 36.0° while this contact angle result could not be measured from the samples of 0 min-treated NFC due to occurrence of large pores between fibers. The tensile strength of the NFC paper with 40 min-treatment time was ~18 times stronger than that of the 0 min-treated NFC paper. Mechanical energy consumption of the high-speed homogenization used to disintegrate NFC was also compared to that of the industrial defibrillation techniques.

Non-wood fibers are projected as fast-growing resources and sustainable alternate materials to reduce deforestation and enhance efficiency in the pulp and paper industry. This paper addressed the paucity of data on the fiber morphological characteristics (Fiber Length, Diameter, Lumen Diameter, and Wall Thickness) and pulping properties (Slenderness Ratio, Rigidity Coefficient, Flexibility Coefficient, Runkel Ratio, Solids Factor, and Luce’s Shape Factor) for Silk Cotton, leaves and stalk of Elephant Grass and Sugarcane Bagasse found in Ghana, especially, as environmental variations may cause differences in regional data. Observed values for the studied parameters were within the suitable range for paper production and differed from those reported for other regions. Elephant Grass (stalk) and Bagasse that had higher values of Fiber Length (4101.42 ± 197.89 and 3960.20 ± 194.35 µm), Diameter (60.03 ± 1.82 and 59.85 ± 1.72 µm), Lumen Diameter (33.33 ± 1.76 and 35.97 ± 1.38 µm), Wall Thickness (13.35 ± 0.83 and 11.94 ± 0.55 µm), Slenderness Ratio (70.8 ± 4.2 and 67.2 ± 3.4), and Flexibility Coefficient (55.7 ± 2.3 and 55.7 ± 2.3) would perform better during paper production. They would exhibit good physico-mechanical properties suitable for manufacturing flexible, high tearing, elastic, dense, smooth, and well-formed papers with high tensile and bursting strengths. Silk Cotton may also produce good papers with low tearing index, well-bonded, rigid, bulky, and coarse textured.

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 properties is when the biopulp is treated with a xylanase enzyme concentration of 0.04% (w/w).

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 analyzed 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.

Paper and cardboard elements can be used as a pro-ecological building material. To meet the safety and usage requirements paper elements need to be impregnated, however, most impregnation methods have a negative impact on the environmental performance of the elements. This article describes research that was conducted in order to determine the most effective technique of paperboard impregnation against water and humidity. Particular attention was given to biodegradable coatings, as several oil-based and wax-based wood impregnates were used. The samples were tested for 24 hours in immersion and for 48 hours in high air humidity. Water uptake (measured by the change in mass and thickness), delamination and deformation of samples were monitored. As a result, the basic characteristic of the tested impregnation methods was established – water and water vapour absorption, deformation or delamination after immersion. The lowest water and water vapour absorption was observed in samples impregnated with composed coatings of oils and waxes.

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.

As a representative colorimetic biosnesor, paper-based LFSA have emerged as a promising and robust tool that can easily and instansly detect the presence of target biological components in food sample. Recently, LFSAs have gained a considerable attention as an alternative method for rapid diagnosis of foodborne pathogens to the conventional culture-based assays such as plate counting and PCR. One major drawback of the current LFSAs for the detection of pathogenic bacteria is the low sensitivity, limiting its practical applications in POCT. Not like many other protein-based biomarkers that are present in nM or pM range, the number of pathogenic bacteria that cause disease can be as low as few CFU/ml. Here, we review current advances in LFSAs for the detection of pathogenic bacteria in terms of chromatic agents and analyte types. Furthermore, recent approaches for signal enhancement and modifications of the LFSA architecture for multiplex detection of pathogenic bacteria are included in this review, together with the advantages and limitations of each techniques. Finally, the technological challenges and future prospect of LFSA-based POCT for the detection of pathogenic bacteria are discussed.

The purpose of this study was to evaluate the effects of bleached kraft mill effluent on selected physiological and hematological endpoints in fingerling largemouth bass (Micropterus salmoides). Fish were exposed for 35 days to surface water collected at sites up- and downstream from a pulp and paper mill treatment-effluent discharge. The condition factor, spleen somatic index, and pronephros cellularity were statistically significantly decreased in fish exposed to the downstream site, compared to the upstream site. There was also a shift from lymphocytes to neutrophils in peripheral blood of fish exposed to the downstream site. Hematocrit values and the liver somatic index were statistically significantly increased in fish in the downstream exposure. These results indicate that in-stream exposure to elemental-chlorine-free pulp and paper mill effluents produce a generalized stress response, leading to potential immunosuppression in fish.

Tamarind seed is an underutilized byproduct of the tamarind pulp industry. Only a small portion of the seed, in the form of tamarind kernel powder (TKP), is used as a sizing material in the textile, paper, and jute industries. Though many applications of this seed are possible, there have been hardly any other uses for it including using it as an additive in food formulations. The excellent gelling cum adhesive characteristics of the decorticated seed powder can lead to several applications in food and pharmaceutical industries which are evident by the number of research papers as well as patent applications. This article thus focuses on the possibilities of using the seed in several food and non-food industries with particular reference to physical and engineering properties, hydration behavior, rheological properties, functional and nutritional characteristics, and the processing of the tamarind seed for wider applications.

Ecosystems provide a wide range of services that improve human welfare. Changes in ecosystems imply potential changes in the generation of these ecosystem services and thus changes in welfare. In the lingo of economists, these welfare changes are measured as changes in economic values--increases in welfare being benefits and decreases in welfare being costs. For instance, individuals may benefit from, and thus value, reductions in risks to endangered species. Yet values for many changes in ecosystem services are not captured in market transactions, and thus measuring these values requires nonmarket valuation methods. This paper discusses ecosystem services and values from the viewpoint of an economist, explains what is meant by the valuation of ecosystems, and provides an overview of methods for valuation of ecosystem services. An example is presented from a recent natural resource damage assessment--the Green Bay total value equivalency study. Resources in the Lower Fox River and Green Bay in Wisconsin have been injured by polychlorinated biphenyl contamination from numerous paper mills along the river over several decades. The Green Bay study examines individuals' preferences and values for reducing ecosystem risks and improving ecosystem services and how these values are related to individuals' awareness of and use of ecosystem services in the area. The study uses methods from nonmarket valuation to scale potential restoration projects.

The increasing application of complex natural and/or synthetic polymers to food packaging has required definitive information on the characteristics of the finished products. High temperature encountered during the manufacturing process may induce thermal decomposition products that can migrate into the packaged product and cause undesirable flavor. A general methodology for testing polymer odor and odor contributors is discussed in this article with examples representing the odor of a variety of packaging materials. The precursors and the mechanisms of the major volatile components of each packaging material are presented.