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The recycling of paper and paperboard waste for obtaining powder cellulose has a positive impact on environmental and economic benefits due to its possibility to be applied in various fields of industry, including the fabrication of wood-polymer composite1,2. The extraction of cellulose from cellulose-containing wastes can be carried out by their mechanical disintegration with acid or alkali hydrolysis. In comparison with the known method3 the proposed method can be realized under more gentle conditions. For this aim, recycled de-inked waste paper was cut into small pieces (d < 5 mm) which were soaked in 0,05% hydrochloric solution at hydromodulus 1/20 (paper/water) for 2 hours at the intensive mechanical stirring for paper pieces disintegration. After soaking, the excessive water was pressed, and the disintegrated paper mass was dried, at first, at 60 °C for 16 hours and then at 120 °C for 2 hours. After drying, the paper mass was milled in a planetary mill for 15 minutes at a moderate rotation speed. The obtained cellulose particles were characterized by physicochemical properties. It was found, that obtained recycled paper particles (RPAP) had a similar contact angles with water compared to reference cellulose powder. However, polarity of RPAP was 20,5%, but of reference cellulose – 43,5%. RPAP could be characterized as more amorphous than cellulose because its crystallinity index was 61%, but reference cellulose powder – 81%. Using laser granulometry, it was found, that 99% of particles were less than 200 μm, and 90% of particles were less than 140 μm.

Several Indonesian paper mills utilize used paper as feedstock as the price is much cheaper and abundant availability, but the strength of the paper product tends to decrease. Xylan which is extracted from corncobs is a potential additive for upgrading the quality by modifying the fibre surface. This research studies the effect of sodium hydroxide concentration for extraction to produce an acceptable strength of paper product. The extraction process is at temperature of 90°C for 2 hours in a stirred tank reactor and the xylan product is deposited with 10 N acetic acid at pH of 4.5 - 5.0. Using 16% of NaOH concentration, the extraction produces 21.82% yield of xylan. With addition of this xylan product at mass ratio between xylan and corncobs of 5% increases 30.1% of the tensile strength and 31.83% of the tire strength. The optimum concentration of the use of NaOH in xylan extraction was at 16% NaOH with the largest xylan yield obtained at 21.82%.

This work developed activated carbon loaded lignocellulosic fibers (kraft pulp) by pulp refining process and used them to form activated carbon paper (AC-paper). AC-paper was used for the removal of dye and heavy metal ions from aqueous solutions. In pulp refining process, kraft pulp was mixed with activated carbon using high consistency refiner with the addition of cationic starch as a binder. The effects of cationic starch and activated carbon concentration on AC-paper properties were investigated. Activated carbon amount of 0, 10, 20, 30, 40 and 50%, and cationic starch amount of 0, 0.25 and 0.50% (% by oven dried weight pulp) were examined. The AC-paper was prepared at basis weight of 60±5 g/m2. Paper mechanical properties, including density, tensile index, burst index, ring crush index, and tear index, were tested according to ISO 5270. The results show that all paper strength properties declined when the amount of activated carbon was increased. Especially, when the activated carbon content above 30%, paper strength was greatly reduced. The improvement of paper strength was observed when with the cationic starch was added. However, the increased of cationic starch amount from 0.25 to 0.50% showed no significantly difference in paper strength. Paper adsorption of dye (methyl orange, (MO)) and heavy metal ions (zinc and iron) were also studied. The AC-paper prepared from fiber with 50% activated carbon and 0.50% cationic starch provided highest adsorption values of both dye and metal ions from aqueous solutions. In this work, the use of 30% activated carbon and 0.50% cationic starch in pulp refining process was chosen as a suitable condition for the preparation of activated carbon loaded fiber because the activated carbon content above 30% could disrupt paper strength. The fiber obtained from this suitable condition gave the paper with adsorption values of 0.62, 16.38 and 16.72 mg/g for MO, Zn2+, and Fe2+, respectively. The developed activated carbon loaded lignocellulosic fibers could be potentially used for various specialty paper products, such as absorbent paper, filter paper and active packaging, in the future.

The separation of oil from water is significance for environmental de-pollution application. To obtain selectivity of liquid, filter papers were coated to bear highly hydrophobic and oleophilic functionality that can allow only oils to pass through them. The coating solutions were prepared by mixing poly(methylhydro siloxane, PMHS) and fumed silica at various proportions. To determine an optimum coating condition, properties of the treated filter papers were investigated by measuring water contact angle and surface free energy, examining surface morphology and testing for selective removal of diesel oil from water. The optimum coating solution was at the PMHS:fumed silica weight ratio of 1.25:1.00. The treated filter paper exhibited high hydrophobicity with water contact angle of 142.80 ± 0.36 degrees and surface free energy of 0.78 mJ/m2. In addition, it exhibited high selective removal of diesel oil from water with oil absorption capacity of 2.3 g/g.

This work presents an enhancement of the voltammetric signal on an electrochemical paper-based analytical device (ePAD) using a graphene oxide (GO) modified carbon electrode. The ePAD is fabricated using a screen printing technique for fabrication of the hydrophobic area and three electrode strips. The graphene film was directly prepared on ePAD by dropping 2 µL of GO dispersed in water onto the working electrode surface and leaving it to dry at room temperature. The electrochemical reduction process of GO was carried out by applying a constant voltage of -1.20 V (vs. Ag/AgCl electrode strip) in 0.1 M KCl for 800 s. The GO-modified carbon working electrode on ePAD was readily obtained and ready to use after removing KCl solution. We tested the enhancement of the voltammetric signal on ePAD with a 6 mM [Fe(CN)6]4–/3– redox couple in 0.1 M KCl supporting electrolyte solution. Our results obtained from cyclic voltammograms showed that the unmodified working electrode and the GO-modified working electrode on ePAD provided similar anodic and cathodic peaks. Due to accelerated electron transfer process, it was found that the GO-modified working electrode on ePAD provided approximately a 2-fold increase in voltammetric signals when compared to the unmodified working electrode on ePAD. The reproducibility (inter-day precision) of the voltammetric signal measurement using a GO-modified working electrode on ePAD was acceptable. The relative standard deviation (RSD) was 5-8%. Therefore, the GO-modified carbon working electrode on ePAD offers an effective approach to enhance the signal and sensitivity for chemical analysis.

Oil impregnated insulation paper plays an important role in a transformer as it insulates the windings from high voltage and current. Other than the type of paper used, the properties of oil such as viscosity, relative permittivity and dielectric loss play a major factor that contributes to the quality of the insulation paper. This paper discussed the sonication and esterification process on palm oil and treated waste vegetable oil and its’ effects on the performance of oil impregnated paper. Basically through these processes, viscosity of oils will reduce. However, the resultant permittivity and dielectric loss as well as its’ breakdown strength are rarely reported. Experiments were set to process (sonicates and esterify) the natural oils prior to the paper impregnation process. Results show that esterification is more effective than sonication process in reducing insulation oil viscosity, relative permittivity and dissipation factors as well as increasing the breakdown voltage of the oil impregnated paper. Palm oil methyl ester (POME) could serve as an excellent insulation oil which is very suitable as transformer oil as well as the impregnation medium for paper insulation.

In present investigation, an attempt was made to optimise the peak stress for paper laminate composite using FRANC2D software. It was observed that the laminate having the triangular geometry supposed to be most appropriate as it has the lowest value of peak stress contour compared to other models like parallel strip, up-down tapered and down-up tapered. The minimum peak stress was observed for the samples having triangular geometry while the maximum was observed for down-up tapered samples. Therefore, the hypothesis adopted to use in-built materials with variables reinforcement area and strip geometry and length in the FRANC2D software to optimize the sample geometry and then apply it to the paper laminate by considering its mechanical properties might be use to optimize the peak stress of paper laminate composite in tensile loading conditions. It was also observed a length of one-quarter of the length of the plane strip, might be the optimum length of the paper laminate samples. However, it feels that, the above model can be further modified considering a more significant mechanical properties as well as different sample geometries.

Fabrication and mechanical properties of the bio-composites between water hyacinth natural fiber and paper mulberry have been investigated. The fabrication was performed using the hand lay-up technique. Untreated and treated water hyacinth fiber were used as reinforcements, in the ratio of 5%, 10%, 15%, and 20% by weight, with paper mulberry as a biomatrix. It has been found that paper mulberry reinforced with 15 % treated WH fiber showed maximum tensile strength and impact energy. The optical and scanning electron microscopic morphology of the obtained composites displayed a rougher surface and the decrease in the fiber diameter when treated with sodium hydroxide (NaOH). This improved the interlocking between the matrix and its reinforcement.

During recycling of waste paper from private households different fractions containing plastics and polluted paper fibers are received. Those polluted fibers cannot be recycled in the common paper manufacturing process or for energy recovery like in waste incinerating plants due t o economic reasons. Current research at the Institute of Polymer Materials and Plastics Engineering at Clausthal University of Technology evaluated the use of this waste paper recyclate as a substitution for natural fibers as fillers and reinforcements in polypropylene. Special attention was given to the mechanical properties of the composites. Additionally the influence of maleic anhydride grafted polypropylene (MAPP) as an adhesive was investigated.

The numbers of Malaysian construction industry had been increasing in several years with the large construction building and infrastructures projects had been constructed. Therefore, these developments led to an increase of cement production. The production of cement will cause wider environmental implication such are air pollution, water pollution and soil pollution which are very dangerous for human health. This is due to the manufacturing of cement that release dust, toxic and carbon dioxide emissions, which is a significant contributor of greenhouse gases. To overcome this problem, several researches had been conducted for the past few decade to find a new waste material that have same mechanical properties which can replace cement content in construction. One of the most promising materials that shows great potential is eggshell as a cement replacement. It is reported that the global egg production will increase to about 90 million tons by 2030, therefore the waste of eggshell will be increased too. This paper study the mechanical properties of eggshell as a cement replacement in concrete. Several papers had been reviewed and the results are presented in order to shows the performance of eggshell in concrete. The result shows that the concrete with less than 15% replacement of eggshell produced higher compressive and tensile strength compared to normal concrete. Moreover, the flexural strength of concrete containing eggshell up to 20% replacement shows comparable results with normal concrete. From the results, by replacing cement with eggshell up to 15% show a good performance as well as can reduce the use of cement and reduce the eggshell wasted in landfill.

Tensile strength test for paper has been regularly used in measurement of paper quality in the industry. In this study, changes in properties of paper during biodegradation were compared by measurement of the tensile strength cellulose activity. Samples of filter paper and polyethylene coated paper were digested with cellulose degrading Bacillus isolates. Treatment with water was used as a negative control. The paper samples were cut into precise shape according to the standard protocol of mechanical tensile strength test to measure the maximum tensile force. After removing bacterial biomass, reducing sugars were measured as a surrogate for callulase activity in the spent fermentation broth and the paper samples were subjected to the mechanical strength, breaking load and stretch tests. The results showed the amount of stretch in paper was critically reduced over longer contact time in bacterial culture. Changes in the mechanical strength were apparent within 3-7 days of contact time, whereas changes in reducing sugars were observed only after 7-10 days of incubation depending on the paper type. In filter paper samples, more reducing sugars and less mechanical strength indicated increased biodegradation of the cellulose matrix. Overall, the mechanical tensile strength test was deemed an early indicator for paper biodegradation that may have commercial application.

This research aimed to investigate the possibility of utilizing coal fly ash and eucalyptus fly ash from boilers in pulp and paper industry as adsorbents for color removal of biological treated wastewater. The physical properties of fly ash such as pore properties (surface area, pore volume and average pore size), thermal degradation and functional group were analyzed. The results showed that both types of fly ash were mesopore adsorbents. The percentage of color removal increased with the increasing of amount of adsorbent. The maximum percentage of color removal for amount of adsorbent at 0.5, 1, 1.5 and 2 g are 76%, 86%, 90% and 94%, respectively. The adsorption reaches equilibrium at 48 hours for all experiments. The adsorbents were reused and the experiments showed that the adsorbent can be reused twice without any regeneration before the percentage of color removal went below the target number of industry at 58%. The scale up of adsorption process was also studied. The experimental results showed that increasing amount of adsorbent and adsorbate 2 to 10 times do not have any significant effect on the percentage of color removal. The coal fly ash yielded higher percentage of color removal (90%) than eucalyptus fly ash (82%).

A simple method was achieved to develop a coating of silver nanoparticles on paper using ultrasonic radiation. Silver nanoparticles were prepared by the chemical reduction method using triethylene glycol as a reducing agent. UV-Vis spectrometry was used to characterize the synthesized silver nanoparticles in solution. The coated papers were characterized the surface features by scanning electron microscopy (SEM) and energy dispersive spectrum (EDS). The particle size distribution was 78 – 311 nm in diameter depending on ultrasonication time. The coated papers revealed the most effective in the antibacterial activity against both Staphylococcus aureus ATCC 25923Tand Escherichia coli ATCC 25922T.

In this work, pulp/lyocell wet-laid paper sheets have been consolidated by hydroentanglement techniques. Scanning electron microscopy has been used to evaluate the structures of wet-laid paper sheets before and after hydroentanglement. Wet tensile strength along longitudinal (preferential) and transverse directions show the effect of hydroentanglement techniques on the mechanical properties of wet-laid paper sheets. In addition, the air permeability and water absorbency properties of materials have been evaluated. The results show that the structures of wet-laid paper sheets become fluffy and fiber entanglements increase after consolidation. The wet tensile strength values of wet-laid paper sheets at the longitudinal and transverse directions are increased by 109.0% and 78.7%, respectively after hydroentanglement. The air permeability and water absorbency of wet-laid paper sheets are increased by 957.6% and 137.0%.

Recycling of paper materials or other type of cellulose fibres is important regarding saving nature resources and environmental protection. Cellulose dissolution and regenerating from various materials is one of recycling possibilities. Cellulose dissolution by NaOH/urea system has a great potential due to the use of harmless reagents, and at the same time is challenging due to the forming of gel-like substances, when cellulose has degree of polymerization more than 1000. It was found that microcrystalline cellulose and cotton cellulose were dissolved in NaOH/urea, but tissue paper, filter paper and waste paper were not dissolved completely. Additives of Kraft pulp and pulp waste dissolved and regenerated from NaOH/urea and cupriethylendiamine (CuETD) in amount 0-30% from paper composition increased mechanical properties of paper sheet. CuETD additive was more effective than NaOH/urea additive, however latter has potential for further research as environmentally friendlier.

In this report, synthesis and characterization of gold nanoparticles (AuNPs) from gold leaf by electrolysis in two different media (gel and paper) in presence of sodium chloride (NaCl), glucose (C6H12O6) and polyvinyl pyrrolidone (PVP) at room temperature were investigated. Graphite was used as two electrodes, NaCl was used as an electrolyte, C6H12O6 was used as reducing agent and PVP was used as stabilizer to control the aggregation of the nanoparticles. UV-Visible spectroscopy (UV-Vis) and scanning electron microscopy (SEM) were used to confirm the characteristics and morphologies of the synthesized AuNPs.

Paper-based microfluidic devices have a significant potential for low-cost diagnostics in the developing world. This study reported a simple fabrication method based on the digitallization of microfluidic technology for paper based microfluidic devices. Melted wax was jetted steadily with PZT actuated microfluidic pulse inertia driving system and pulled-forged glass micronozzle in the form of droplets. The wax melted into filter paper to form hydrophobic wall and different patterns for paper microfluidic devices were made. The influence of system parameters such as driving force, frequency, the fabrication process and the tip diameter of glass micronozzle on the wax line width was experimentally studied. 75 μm500 μm wax lines were achieved with the wax printing system. The paper microfluidic devices fabricated could lead the capillary action of black ink and the color change reaction of NaOH and phenolphthalein solution. Result showed that the wax printing system is simple structured and this method suggests a novel path to develop simple, inexpensive, and portable diagnostic assays.

Polyaniline-zinc oxide composite on Kapok paper were fabricated for methylene blue dye removal in aqueous solution. Kapok fibers were fabricated into papers. The fabricate paper served as substrate for the zinc oxide-polyaniline composite. Zinc oxide particles were deposited on the Kapok paper using an in-situ method while polyaniline molecules are deposited on paper using Successive Ionic Layer Adsorption and Reaction (SILAR) method. The polyaniline molecules were deprotonated using sodium hydroxide (NaOH) to be able adsorb cationic dyes in aqueous solution. The samples were characterized using scanning electron microscope (SEM), energy dispersive X-ray (EDX) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Results show that the deprotonated polyaniline nanocomposite was able to remove at about 75% more dye compared to the as-synthesized polyaniline nanocomposite.

Nanostructured zinc oxide (ZnO) particles were grown on paper substrate made from Abaca hybrid 7 pulp. Microwave irradiation technique was used at power levels (180 and 540W) and exposure times (5, 10, 20 and 25 minutes). Chemical transformations were observed using Fourier Transform Infrared (FTIR) Spectroscopy. The effects of the power levels and exposure times on the morphology of the nanostructures were determined using scanning electron microscopy. FTIR spectra proved the embedment of ZnO on the paper substrate. Power levels and exposure times affected the distribution, particle size and structure of the ZnO nanoparticles. Higher power level and longer exposure resulted to the formation of more ZnO with larger particles. Grainlike and flowerlike ZnO nanostructures were formed at lower and higher levels, respectively.

This research studied the feasibility of using natural fibers extracted from natural wastes as a thermal-insulating material lined in a Kraft paper box packaging. The natural fibers were extracted from natural waste of rice straws using NaOH solutions. The extracted fibers were then formed as a porous thermal-insulating pad by a spray lay-up method using natural rubbers as binders. The thermal conductivities, specific heat capacities and temperature-rise time of the natural fiber insulation and other thermal-insulating materials including polystyrene foam, a polyethylene foam, and a glass fiber insulation were studied and compared. The glass fiber insulation showed the highest thermal conductivity, while the thermal conductivities of the other studied insulating materials were found to be similar. Moreover, the polymeric and natural-fiber insulations show better temperature-rise resistance than the glass fiber insulation. The temperature rises for different insulating materials were estimated using the analytical analysis of heat transfer. The calculated temperature-rise times were compared with the empirical results; both results are in the same order of magnitude. Consequently, a Kraft paper box lined with natural-fiber pads was constructed and compared with a Kraft paper box (without insulation lining) and a polystyrene box of equal sizes. The boxes were packed with an equal amount of ice and left under room temperature for 24 hours. The results show that, after 24 hours, the temperatures inside the natural-fiber lined box and the polystyrene box were contained below 15 °C, while the temperature inside the Kraft paper box increase to room temperature only after 16 hours. The observation shows that a natural fiber pad can potentially be used as an alternative insulating material in packaging industries, which can enhance environmental-friendly packaging products.

Nickel cobaltite (NiCo2O4) nanowires were successfully grown on the surface of carbon fiber via hydrothermal treatment, followed by annealing. After 2 h, SEM revealed the formation of NiCo2O4 nanowire arrays on the surface of the carbon fiber paper. With increasing hydrothermal time from 2 to 12 h, the NiCo2O4 nanowires also self-assembled into urchin-like morphologies. When used as catalysts for hydrogen evolution reaction, the NiCo2O4 nanowires exhibit an onset potential for the cathodic current at-0.13 V vs. Ag/AgCl in 0.1 M KOH.

We experimentally investigated compressive behaviors of a paper and a paper coated by polyethylene resin. The initial thickness of sheets of paper measured under a compressive stress of 4.5kPa was widely distributed in comparison with the basis weight, although the results based on the ISO 534 standard (under compressive stress of 100kPa) had relatively little dispersion. For compressive deformation, the thickness immediately decreased under low compressive stress, because the gap between fibers in the paper collapsed. After that, the variation of the thickness under higher compression was small due to the compression of fibers. We found that although the resin-coat layers did not have an insignificant effect on compressive compliance above 250kPa, the compliance of the coated paper was larger than that of uncoated paper.

The pigment electrophoresis dispersion has been the widely used system. It is, however, worth of attention if molecular dye, instead of pigment, can be used in the display of electronic paper. By carefully selecting the structure of dyes, especially the metal complex dyes, and studying the properties of the prototype display. It was found there are about 15 dyes electrophoresis and some dyes display well. The dyes ink with good stability during electrophoresis when the electrode was protected, while the response time is about 300 ms, and the concentration is an important factor on the display optic density. The displaying principle of dye ink was studied too.

Cellulose and lignocellulose have great potential as nanomaterials because they are abundant, renewable, have a nanofibrillar structure, can be made multi¬functional and self-assemble into well-defined architectures. New methods for liberating these materials, including nanodimensional cellulose fibrils, macromolecules and nanominerals will be needed in order to use the techniques developed for other nanomaterials as platforms for creating new wood-based materials and products. Research findings showed promising results in application of nanotechnology at different aspects of papermaking. Electrospinning; chemical treatment followed by mechanical techniques; or mechanical isolation methods were applied by different research groups to prepare cellulose nanofibres.

Producing particulate filled polymer composites, even dispersion and sufficient adhesion between filler and polymer matrix is of great importance. In order to solve these issues, methodologies, such as ultrasonic dispersing and coupling agents, are proposed. The impact of particle surface modification with three different titanate coupling agents having the tradenames of TCA L44, TCA L38 and TCA K44 on paper waste sludge particles surface, polyurethane foam composite density, compressive and tensile strengths as well as water absorption and water vapour permeability is evaluated. Apparently, titanates form layer on the particle surface, thus increasing the interfacial adhesion between particles and polymer matrix. Basing on the obtained results, the optimal amount and type of titanate is 1 wt.% of TCA K44.

In this work the crack initiation stress of notched specimens of filter paper is studied. The paper in the microstructure has a random array in their fibers while macroscopically it behaves anisotropically. The self-affine crack mechanics is used to study the size effect in the tensile behavior of this kind of paper under the presence of several conditions of geometrical notches. While in the traditional fracture mechanics the crack initiation stress is a material parameter when is reached a critical level at the crack tip, in the self-affine crack mechanics, depends moreover of the resulting tortuosity of the crack. Four geometrical arrangements in two sizes we considered: centered circular notch, centered lineal notch, sided circular notches and without notch at 10 and 300 mm width with a relation 2a/w = 0.25 under the same loading conditions. In this, the without notch specimens present the higher stress, all other notched specimens presented a similar crack initiation stress about 1 % of difference among them, and the crack growth is not affected by the geometry of notch. In spite of this difference, no one of the specimens reach the theoretical stress concentration of 3 such as predicted the classical stress theory.

The aim of the present study was to improve the paper handsheets parameters by adding biodegradable natural polymer – chitosan. The addition of chitosan in the amount of 2-4% improved tensile strength of the handsheets by up to 20% in dry condition and by up 5 times in wet state. Addition of chitosan increases the hydrophobic properties of paper as it was revealed by contact angle and water penetration dynamic measurements.

The crystal structure of aramid fibers is highly orientated. The structure of aramid fibers with various manufacturing processes and aramid paper sheets were analyzed and observed by using polarized light microscope (PLM). The change and its law of aramid fiber crystal structure in such processes as aramid fiber mamufaturing of aramid fiber/fibrids, forming of aramid paper sheets, and heat treatment were analysed. The relationship between the structural feature of aramid fibers and the performance of aramid paper was also discussed.

In this study, Al2O3 fiber composite papers with a certain strength and flexibility were prepared by pressure filtration. Microstructure and pore size of the composite papers with different density were investigated and thermal conductivities were measured by plane table thermo-conductivity meter at 600°C to 1200°C. Then the relationship between density ρ and thermal conductivity λ was studied, and the optimum density of Al2O3 fiber composite papers at different temperature was determined.

In this work the self-affine crack pattern in Filter Paper sheets is studied. This paper has a well-defined anisotropy of mechanical properties associated with visible preferable orientation of fibers in the machine direction. Fracture behavior is in essence brittle, the rupture lines have self-affine invariance, and the stresses ahead of the straight notch follow a power-law behavior. The roughness exponent value is of H = 0.50 0.01, different from the suggested universal value H = 0.8. The classical theory has demonstrated that, in materials such as metal, there is a relationship between the size and the starting crack stress, which does not happen in this material. The tests show that the starting crack stress from stress-strain behavior curves remains stable for the different specimen sizes w and crack length size. Moreover, different types of geometric groove, circular and linear, and without a crack, were tested and show almost the same behavior.

Effect of metal modification to carbon paper as the anode of mediator-aided yeast-based microbial fuel cell on the cell performance was investigated using methylene blue as an exogenous mediator. The modification was conducted using a sputtering technique by depositing Co or Au thin layer, 30 nm. The electrode performance was evaluated by measuring the electrode potentials and the fuel cell power output. The metal modification significantly increased the mediator-aided MFC performance.

Effect of modification of carbon paper with a thin layer of cobalt or gold on the performance of yeast-based microbial fuel cells was investigated. The modification was conducted by depositing Co or Au thin layer with different thickness, 5 nm and 30 nm, using a sputtering technique. The electrode performance was evaluated by measuring the electrode potentials and the fuel cell power output. The Co modification significantly increased the performance of the fuel cell, while the Au modification inhibited the performance. SEM observation indicated that the adhesion density of the yeast cells on the electrode surface was affected by the metals. It was confirmed that the electron transfer took place through the surface confined species at the mediatorless anode.

The unitary thermal insulation fiber materials can not satisfy rigorous high temperature environment usually. New inorganic coatings were prepared by adding SiO2 aerogels super-insulation powder into high temperature adhesive. Aerogels are high dispersive solid materials which consist of colloid particles or high polymer molecule and have continuous random network structure filling with gaseous dispersive medium. The coatings with super insulation function were made by means of adding thermal-proof materials to the coatings. The microstructure of light porous power and the states of coatings on the surface of fiber paper under different state were observed by scanning electron microscope (SEM). The insulated effect of the composite materials was tested by considering thermal conductivity. On the basis of this, the coatings on the surface of fiber paper were optimized according to the material thermal-insulation performance and the materials that could be satisfactory to the service conditions were made in the end. The results show that silica aerogels powder is dispersed equably in high temperature adhesive. The new inorganic coatings possess themselves of good thermal-insulation effect and can be used as insulated space-layers. The insulation ability of fiber paper is improved obviously.

NaX molecular sieve films on ceramic paper prepared by in-situ hydrothermal method were investigated. The NaX zeolite seed crystals of a uniform size of 5 µm were synthesized by hydrothermal method in a mother solution having a composition of 3.5Na2O : Al2O3 : 2.1SiO2 : 500 ~ 1000 H2O. These dip-coated NaX seed crystals on ceramic paper lead to further the thickness (20 ~ 100 µm) of NaX film on the substrate at 90°C for longer 3~7 days in autoclave. Pure zeolite films consisting of a continuous intergrown of 5~ 20 µm NaX crystal have been prepared on the substrates. The zeolite films were characterized by XRD, SEM, BET and XRF.

A new effective fabrication module was developed to mediate the problem of the low yield of Indium-tin-oxide (ITO) nanostructures deposition uses micro electroremoval technology and a design of twins-cylinder tool as a precision etching process to remove the defective Indium-tin-oxide (ITO) from the optical PET diaphragm surfaces of digital-paper displays. For the removal-process, a small gap width between the negative electrode and the workpiece (optical PET diaphragm) surface corresponds to a higher removal rate for the ITO. A small diameter of the anode or a small diameter of the cathode of the twins-cylinder tool provides large electric current density and takes less time for the same amount (20 nm) of ITO removal. High rotational speed of the twins-cylinder tool the discharge mobility and results in improving the removal effect. Providing enough electrical power can uses fast feed rate of the optical PET diaphragm combined with a fast removal rate for ITO. With increasing in current rating, pulsed direct current can improve the effect of dregs discharge and is advantageous to associate with the fast feed rate of the optical PET diaphragm. By establishing a recycling process using the ultra-precise removal of thin-film nanostructures, through the micro electroremoval and the twins-cylinder electrodes requires only a short period of time to remove the ITO thin-film easily and cleanly. The optoelectronic semiconductor industry can effectively recycle defective products, minimizing both production costs and pollution.

The application of electroactive polymer devices requires the availability of their properties at various operating conditions. This in turn necessitates a structure-property relationship based on an in-depth understanding of the underlying mechanism responsible for their strain-field response. Cellulose-based Electro-Active Paper (EAPap) has been studied as an attractive Electro Active Polymer (EAP) material for artificial muscles. The feasibility of EAPap material as an actuator/sensor application is greatly dependant on piezoelectric effect. In this paper, converse and di rect piezoelectric ef fect s of Electro-Active Paper materials are studied to characterize piezoelectric effects of EAPap. All experiments were conducted in an environmental chamber that can control temperature and humidity.

Electro-Active Paper (EAPap) is attractive for a biomimetic actuator material due to its merits in terms of lightweight, dry condition, large displacement output, low actuation voltage and biodegradability. However, the performance of EAPap actuator is so sensitive to humidity that high humidity is required. We report a robust EAPap actuator that can be activated in room humidity condition. The EAPap is made by dissolving cellulose fibers into a solution using DMAc solvents, and made into a sheet by using casting. Thin electrodes are deposited on the cellulose paper to comprise an EAPap actuator. The fabrication process and the performance evaluation of EAPap are presented in terms of free displacement with respect to frequency and actuation voltage.

Electro-Active Paper (EAPap) materials based on cellulose are attractive for many applications because of their low voltage operation, lightweight, dryness, low power consumption, bio-degradability. The construction of EAPap actuator has been achieved using the cellulose paper film coated with thin gold electrode layers. This actuator showed a reversible and reproducible bending movement. In order to improve both force and displacement of this, efforts are made to construct hybrid EAPap actuators using cellulose paper coated with carbon nanotubes (CNT). To coat the CNT, single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT) are dispersed in polyaniline (PANI) matrix, and the solution is coated on the EAPap by using a spin coater. It is expected that the use of CNT can improve the force output by enhancing the stiffness of the hybrid EAPap actuator. Furthermore, the presence of the PANI may improve the actuation performance of the EAPap material. The performance of hybrid EAPap actuators is tested in an environmental chamber in terms of free displacement, blocked force and electrical power consumption. The performance of hybrid actuators is investigated for bio-mimetic applications.

Cellulose-based Electro-Active Paper (EAPap) has been studied as an attractive electroactive polymer material for artificial muscles due to its low cost, availability, lightweight, large displacement output, low actuation voltage and low power consumption. However, the force output of EAPap is small since paper is so flexible that the bending stiffness is low. In this paper, the cellulose based EAPap material is enhanced by using carbon nanotubes with cellulose paper. Coating of multi-walled carbon nanotubes mixed with polyaniline on EAPap as well as MWNT dispersion in the paper are tried to enhance the force output of the EAPap. The coating process of MWNT/PANI on the EAPap and the dispersion of MWNT in the cellulose paper are explained. The performance of the hybrid EAPap actuators is evaluated in terms of tip displacement, blocking force and electrical power consumption. The power output and the actuator efficiency are improved.

This paper presents the characterization of Electro-active paper (EAPap). EAPap is a paper that produces large displacement with small force under electrical excitation. EAPap is made with a cellulose paper by constructing thin electrodes on both sides of the paper. When electrical voltage is applied to the electrodes the EAPap produces bending displacement. To be able to apply EAPap in many applications, characterization of EAPap is essential to understand and improve EAPap actuators. The characterization is done in terms of mechanical, electrical and physical tests. Mechanical strain and strength are investigated in sheet level and thermo-mechanical analysis is performed. Electrical resistance and admittance are analyzed to investigate the actuation mechanism. The actuation principle associated with piezoelectric effect is explained. EAPap has merits in terms of lightweight, dry condition, large displacement output, low actuation voltage and low power consumption. The most attractive characteristics of EAPap materials is their application potential for the development of biomimetic systems that are ultra-lightweight, low power, flexible, damage tolerant, noiseless, and agile.

Epoxy ecocomposites reinforced with recycled paper (rP) and nano-kaolinite (nK) have been synthesized. The effect of seawater soaking on the flexural and impact properties have been characterized. This new but cost-effective approach has been developed to improve the physical and mechanical properties of polymeric materials without adversely affecting their processing characteristics. The micromechanisms of toughening and failure processes are discussed.

The SiC/Si multilayer composites were fabricated successfully by reaction sintering method with normal stacked papers as the raw materials. Paper was cut into rectangular sheets and stacked, then infiltrated with phenolic resin to get a laminar structure. This paper /resin laminar composite was transformed into porous carbon with laminar structure after heating at 800 oC for 2h in N2 atmosphere. Finally this porous laminar carbon was reheated with silicon powder at 1450-1650oC for 1-2h in a vacuum furnace and SiC/Si multilayer composites can be obtained through the in-situ reaction between carbon and liquid silicon. The microstructure, reaction mechanism, phase composition and mechanical properties of these multilayer composites were researched. The final material shows a distingished laminar structure with alternating arrangement of SiC thick layers and silicon thin layers. SiC layer was composed by beta-SiC and a little of free silicon and carbon not reacted. The capillarity infiltration and in-situ reaction of liquid silicon act key roles in this process. Higher strength and non-catastrophic failure mode for this material were observed.

The application of bamboo by-products such as bamboo branches, chips to recycle and produce pressed bamboo pulp is an urgent task in Vietnam. It perfectly replaces natural wood with artificial wood embryos from bamboo powder, which has both economic benefits of reserving the source of raw materials, environmental protection... The paper presents a study of the influence of technological parameters on the water absorption and swelling thickness of pressed bamboo pulp plywood in order to ameliorate the quality of pressed bamboo pulp plywood in production of new materials for civil engineering with environmentally friendly bamboo wood pulp materials.

Rice straw, an abundant agricultural waste, is shown to be a promising resource for pulp and paper packaging manufacturing. In this study, rice straw pulps or cellulose fibers were extracted using a soda-AQ process and then the rice straw pulp slurries were refined by a Valley beater. The effect of refining time (15-60 min) on the pulp fiber characteristics was studied. It was found that both initial fiber length and width were decreased with refining time. The refined fibers became fibrillated, finer, and also more uniform in size confirmed by SEM. The pulp freeness (CSF) was reduced with increasing refining time as expected due to higher water-holding capacity of more fibrillated pulps. Then, the molded sheets were formed from the prepared rice straw pulps and examined. From tensile testing, the results indicated that the tensile properties of the molded sheets from the refined pulps were significantly enhanced (p < 0.05), thanks to an increase in fibrillated fiber surface area and inter-fiber bonding degree. The Valley beater refined rice straw pulp provided the molded sheet with the highest tensile index of 51.96 ± 4.08 Nm/g which are comparable to that of the sheets prepared from PFI mill refining process. The tensile properties of the current refined sheets were also in the acceptable range for typical commercial molded pulp packaging. In addition, the freeness values of the optimal Valley beater refined pulps are relatively high (348-423 ml), implying a benefit in forming process and manufacturing of pulp products.

This research focused on the mathematical model that could be simplified as the series function. This function used for macroscopic explanation of the relationship between shear modulus and Brinell hardness of fibrous composites. Kraft paper was used as the sample for this testing. The paper-grammage was varied as following:150, 230, and 420, whereas, the dwell time of indentation was ranging as: 10, 20, and 30 seconds, respectively. And then, the correlation between shear modulus (G) and Brinell Hardness Number (BHN) was obtained by using the simulation of experimental results. These were collected by the Brinell hardness testing machine. After that, the refitting process was analyzed using the polynomial based on linear and quadratic model, respectively. It was found that the interpretation of G-BHN relation using the quadratic be better than the linear one. Because of the coefficient of determination (R2) that analyzed by quadratic function present in higher value than another one.

This paper focuses on the problems of ash deposition and corrosion caused by alkali metal chloride in biomass boiler. Kaolin, pulverized coal ash, silica fume, dolomite, limestone and bauxite are used as additives in this study, to investigate the degree of corrosion of four metal materials on biomass boiler. The results show that the corrosion rate of metal samples is significantly reduced after adding additives. Kaolin, pulverized coal ash, silica fume and bauxite show much obvious effect on corrosion inhibition. Corrosion resistance of four pipe metals: T91>15CrMoG>12CrMoVG>20G, in which the corrosion resistance of T91 is much better than the other three metals.

Many plant wastes are not currently used in production, they are disposed of in landfills or incinerated. The aim of this study is to develop a composite thermal insulation material from unused spinning waste of flax and cotton fibers and soft wood waste. Samples of thermal insulation materials from plant waste were made by drying using the technology of production of soft wood fiber boards. For composite board defined physico-mechanical characteristics and thermal conductivity. The experiment was carried out according to a second-order plan, regression models of the dependences of the material indicators on the proportion of the binder additive, drying temperature and the proportion of wood waste additives were developed. The study showed that composites from unused spinning waste of plant fibers and soft wood waste have the necessary strength under static bending, the swelling in thickness after staying in water is much lower in comparison with the performance of boards from other plant fillers. The coefficient of thermal conductivity of the boards is comparable with the indicator for mineral wool boards.

Papermaking in Malaysia is basically based on recycled (secondary) fibers which are sourced from various parts of the world with prices depending on the quality of the fibers procured. The costs of paper production could possibly be reduced by using local fibers as partial replacement provided that the strength requirements are not compromised; and one such type is the oil palm fibers which are obtained as the by-product of the palm oil industry. This paper reports the use of the oil palm empty fruit bunch (OPEFB) fiber as a partial substitute in the production of corrugating medium. Both unbleached and totally chlorine free (TCF) bleached OPEFB pulps were mixed in different ratios with high quality recycled pulps which had been mechanically and chemically treated. Burst strength results indicate as high as 70% recycled pulp can be replaced by OPEFB pulps yet still having strength properties that are comparable with the industrial produced corrugating medium. Although the effect of bleached pulp is significant at high addition levels of more than 70%, the cost-energy balance will not be effective to use these bleached fibers, and furthermore the utilization of unbleached pulps also gave the same desired results. The use of the underutilized OPEFB fibers for replacement of imported recycled fibers without compromising the paper strength qualities could help the Malaysian paper industry in their quest for finding fiber alternatives.