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The coating process on food packaging paper is carried out to improve the food safety aspect from dangerous substance migration from food packaging into food. It can facilitate to increase its function and wide the potency of utilization. The coating materials commonly used are plastic and wax coatings. Chitosan as a natural polymer that has the binding properties both water and oil. Chitosan has polar and non-polar groups thus it is potential to be developed as a coating material for food packaging paper. The purpose of this study was to determine the physical-mechanical and antimicrobial properties of food packaging paper from oil palm empty fruit bunches pulp coated with chitosan. The parameters used were chitosan and pulp weight. The oil palm empty fruit bunch pulp was fibrillated with high speed blender then mixed with chitosan solution. The mixed solution was poured in the mold and dried in an oven at 60 °C for 24 hours. The results showed that increasing of chitosan content was coated paper increased physical and mechanical properties values. The more pulp content the higher the physical properties value, however the mechanical properties value tend to decrease. The antimicrobial activity of chitosan coated paper was evaluated by measuring the diameter of the inhibition zones. The results revealed that all tested samples showed growth inhibition zone againts to Escherichia coli and Staphylococcus aureus after 24 h incubation compared to commercial food packaging paper.

A paper battery is a 6 cm × 4 cm × 1 mm dimension battery that uses CuCl as a cathode, magnesium as an anode, and urine as an electrolyte. CuCl2 dan CuSO4 as used to synthesis CuCl was analyzed. A simple and cheap sandwiched fabrication model has been identified using the low-cost CuCl synthesis process. This paper battery has passed experimental testing and delivers the best power generation at 169,588 mW and continuously up to 4 hours. Voltage also measured and provided a stable voltage at least for 6 hours at 582.667 mV. Method 2 of using CuSO4, which has price lower than CuCl2 showed better power generation and stability.

We have developed a flexible reduced graphene oxide (RGO) temperature sensor on filter paper based cellulose substrate using vacuum filtration method. One of the most commonly used synthesized methods for RGO thin films is vacuum filtration process. It has several advantages such as simple operation and good controllability. The structural analysis was carried out by FE-SEM, in which the surface morphology images confirm the formation of RGO nanostructures on the filter paper substrate. It was observed that the pores of the filter paper were completely filled with the RGO material during the filtration process, subsequently the formation of continuous RGO thin films. As a results, the RGO films exhibits a piezoresistive property. The resulted RGO based films on the filter paper reveals the semiconducting behavior having sensitivity of 0.278 Omega/degrees C and negative temperature coefficient (NTC) about -0.00254 Omega / Omega /degrees C. Thus, we demonstrate a simplified way for the fabrication of RGO films on filter paper that possesses better and easier measurable macroscopic electrical properties. Our approach is for easy way of electronics, cost-effective and environment friendly fabrication route for flexible conducting graphene films on filter paper. This will enable for the potential applications in flexible electronics in various fields including biomedical, automobile and aerospace engineering.

Recycled paper mill effluent (RPME) contains high concentrations of organic matters and total solids, and therefore requires proper treatment prior to discharge. There is a lack of experimental data available on the biodegradation of solids contents of RPME and digested sludge in anaerobic reactors. In this study, the treatment of RPME was studied using five compartments modified anaerobic inclining-baffled reactor (MAI-BR). The compartmental profiles of TSS, VSS, TDS and lignin contents, and floc size were investigated at different influent chemical oxygen demand concentration (CODin) from 1,000 to 4,000 mg/L, and hydraulic retention time (HRT) from 3 to 1 days (corresponding to organic loading rate (OLR) from 0.33 to 4 g/L day). The results showed that the contents of TSS, VSS and lignin were the highest at Compartment 1 (14,818-32,130 mg/L), (6,772-20,548 mg/L) and (7-227 mg/L), and gradually decreased towards Compartment 5 (627-8,518 mg/L), (281-6,145 mg/L) and (7-22 mg/L), respectively. Conversely, the content of TDS was low at Compartment 1 (508-712 mg/L) and slightly increased towards Compartment 5 (531-836 mg/L). Throughout 126 days, the floc size at Compartmental 1 was increased from 104 to 731 µm, similarly for other compartments. These results concluded that Compartment 1 played a major role in the operation of MAI-BR treating RPME.Recycled paper mill effluent (RPME) contains high concentrations of organic matters and total solids, and therefore requires proper treatment prior to discharge. There is a lack of experimental data available on the biodegradation of solids contents of RPME and digested sludge in anaerobic reactors. In this study, the treatment of RPME was studied using five compartments modified anaerobic inclining-baffled reactor (MAI-BR). The compartmental profiles of TSS, VSS, TDS and lignin contents, and floc size were investigated at different influent chemical oxygen demand concentration (CODin) from 1,000 to 4,000 mg/L, and hydraulic retention time (HRT) from 3 to 1 days (corresponding to organic loading rate (OLR) from 0.33 to 4 g/L day). The results showed that the contents of TSS, VSS and lignin were the highest at Compartment 1 (14,818-32,130 mg/L), (6,772-20,548 mg/L) and (7-227 mg/L), and gradually decreased towards Compartment 5 (627-8,518 mg/L), (281-6,145 mg/L) and (7-22 mg/L), respectively. Conversely, t...

The paper is focused on investigation of the nature and size of cellulose fibers in the structure of stabilizing additives for stone-mastic asphalt concrete, as well as on determination of fibers retention capacity based on their geometric parameters. To obtain the results a scanning electron microscope JSM-6510LV was used, with the help of which 15 to 20 photomicrographs were obtained. It was found out that in all inspected samples of stabilizing additives over 80% of pulp and paper fibers have a band structure with filaments from 0.56 to 1.4 micrometer in length. The fiber thickness in all cases slightly varies within the range of 0.008 to 0.021 micrometer. For a more detailed analysis of the additives the X-ray microanalysis was carried out. The results showed that in all cases the component distribution of the chemical elements present in the additive is inhomogeneous and has two fundamental differences in the oxygen (O) and carbon (C) content. ARMIDON additives contain more than 79% carbon (C) and just 6-13% oxygen (O). VIATOP 66 and SD-1 additives contain up to 61% carbon (C) and up to 48% oxygen (O). Tests to determine the runoff of the organic binder showed that additives with cellulose fiber filaments up to 0.6 micrometers in length hold bitumen worse than additives with cellulose fiber filaments 1.4 micrometers in length.The paper is focused on investigation of the nature and size of cellulose fibers in the structure of stabilizing additives for stone-mastic asphalt concrete, as well as on determination of fibers retention capacity based on their geometric parameters. To obtain the results a scanning electron microscope JSM-6510LV was used, with the help of which 15 to 20 photomicrographs were obtained. It was found out that in all inspected samples of stabilizing additives over 80% of pulp and paper fibers have a band structure with filaments from 0.56 to 1.4 micrometer in length. The fiber thickness in all cases slightly varies within the range of 0.008 to 0.021 micrometer. For a more detailed analysis of the additives the X-ray microanalysis was carried out. The results showed that in all cases the component distribution of the chemical elements present in the additive is inhomogeneous and has two fundamental differences in the oxygen (O) and carbon (C) content. ARMIDON additives contain more than 79% carbon (C) and ju...

Here, a small analytical device was fabricated on both nitrocellulose membrane and filter paper, for the detection of biotinylated double-stranded DNA (dsDNA) from 1 nM. Zif268 was utilized for capturing the target DNA, which was a zinc finger protein that recognized only a dsDNA with specific sequence. Therefore, this detection platform could be utilized for PCR result detection, with the well-designed primers (interpolate both biotin and Zif268 binding sequence). The result of the assay could be recorded by a camera-phone, and analyzed with software. The whole assay finished within 1 hour. Due to the easy fabrication, operation and disposal of this device, this method can be employed in point-of-care detection or on-site monitoring.

Wood fiber derived cellulose has been mainly used as the raw material in the papermaking. However, currently the paper production capacity is greater than the availability of wood. To overcome this problem, there have been many attempts to use non-wood fibers as substitutes for papermaking such as the fibrous materials derived from agriculture wastes. In this research, the paper was made from sugarcane bagasse which was previously delignified using soda process. The research was conducted by varying NaOH concentrations of 8 –16%, delignification temperatures of 60– 100°C and times of 30 –150 min. The aim of the research was to study the effect of delignification process on physical properties of sugarcane baggase soda pulping. The results showed the increase in tensile strengths as the NaOH concentrations increased. Tensile strength was increasing up to optimum temperature and time and then decreased. The water uptake results showed the opposite tendencies with those of tensile strength. The optimum condition was achieved at the NaOH concentration of 10 %, delignification temperature of 80 °C, and time of 90 min. Tensile strength and water uptake achieved at this optimum condition were 27.42 N/mm2 and 240 g/m2, respectively.

Malaysia is facing serious challenges in dealing enormous quantities of waste paper sludge produced in the country every year. This enormous quantity causing major economic problems and environmental problems over the paper and board industry. In order to confront with the economic problems associated with waste disposal costs, which make up almost half of the cost of wastewater treatment, there is a need to provide a viable solution to the reuse of waste and by reducing the use of natural resources. Hence, a comparative analysis of the experimental results novel properties of fresh and hardened concrete with recycled concrete aggregates (RCA) with different substitution of waste paper sludge ash (WPSA) as a partial substitute for cement is presented in the paper. Recycled aggregates is made by crushing the waste concrete cube laboratory tests. Recycled aggregate is made by crushing the concrete waste at laboratory. Utilize of WPSA and RCA is estimated to produce significant gains in strength performance ...

Paper sheets were produced from bleached kraft pulp, and office and newsprint waste paper. Nanoparticles from black alder bark, grey alder bark and pine bark as well as birch sawdust were obtained for using them as reinforcing fillers in paper. Non-extracted bark and that extracted in biorefinery were used. For producing nanoparticles, the materials were destructed using the thermocatalytic destruction method and then dispersed in water medium in a ball mill. At a sufficient concentration, gel-like dispersions were obtained, which contained nanoparticles with the size ~300 nm. The dispersions were introduced in paper furnish in different amounts. It has been established that all the nanoparticle fillers increase the tensile index and burst index in dry and wet states. The nanoparticle fillers from extracted bark increase the mechanical indices to a higher extent. At 20% filler content, tensile index in a dry state increases in the case of non-extracted grey alder bark, black alder bark and pine bark by 28...

A simple and economical method has been used to grow macroscopically reduced graphene oxide (rGO) paper for device application. Synthesized paper has been characterized by different experimental techniques namely SEM, TEM, Raman and UV-Vis spectroscopy respectively. Besides these, temperature dependent electrical studies of rGO paper have also been carried out.

The micro-fibrillated cellulose crystals from natural cotton fiber via alkaline treatment and acid hydrolysis were explored as possible reinforcement in recycled paper to improve its mechanical properties. Results confirmed the characteristic properties and crystallinity of the obtained micro-fibrillated cellulose crystals. Reinforcement of the micro-fibrillated cellulose crystals in the production of recycled paper showed an improvement in the tensile strength compared to the recycled paper samples without reinforcement or even with kapok fiber/micro-fibrillated cellulose crystals combination. Further improvement on the barrier properties of the micro-fibrillated cellulose reinforced paper via biocoating made from chitosan/starch blend resulted to a 27.69% decrease of the water absorption capacity compared to uncoated sample using the Cobb test.

During recycling of waste paper from private households different fractions containing plastics and polluted paper fibers are received. Current research at the Institute of Polymer Materials and Plastics Engineering at Clausthal University of Technology showed that the use of waste paper as filler and reinforcement in polypropylene leads to nearly the same mechanical properties as natural fibers like flax, sisal and hemp. The present investigations focus on the chemical cleaning of the paper recyclate to treat the fiber surface and to solve foreign plastics like polystyrene. For this purpose Soxhlet extraction with different solvents is used. The received extracts are examined via infrared spectroscopy, as well as the treated and the untreated fibers. Afterwards, the cleaned paper is incorporated into polypropylene. The received composites are investigated regarding their mechanical properties by tensile testing and Charpy impact testing.During recycling of waste paper from private households different fractions containing plastics and polluted paper fibers are received. Current research at the Institute of Polymer Materials and Plastics Engineering at Clausthal University of Technology showed that the use of waste paper as filler and reinforcement in polypropylene leads to nearly the same mechanical properties as natural fibers like flax, sisal and hemp. The present investigations focus on the chemical cleaning of the paper recyclate to treat the fiber surface and to solve foreign plastics like polystyrene. For this purpose Soxhlet extraction with different solvents is used. The received extracts are examined via infrared spectroscopy, as well as the treated and the untreated fibers. Afterwards, the cleaned paper is incorporated into polypropylene. The received composites are investigated regarding their mechanical properties by tensile testing and Charpy impact testing.

Paper is a widely used material that is affected by environmental stresses and makes paper prone to damage. The paper is characterized by the absorption of water and moisture due to porosity, We have overcome this problem by employing polymer materials as water-resistant coatings acting as a barrier to protecting the paper, Polymer paper coating forms a clear membrane on the fiber forming a bridge of monomers on the surface of the paper. Two polymer coatings were used as a treatment, namely Polystyrene and sealer (alkyd resin). The results showed the possibility of enhancing the durability of the paper and preserving it from damage and deterioration. The treatment gave a decrease in moisture content, response to abrasion and scratching while increased folding tolerability, the burst strength, tear resistance, hardness compared to untreated paper and the paper porosity important indicator to overcome. The degree of brightness, the degree of color and visible light and ultraviolet radiation [UV] effect of the specimens were studied in detail.

In this paper we report some tests regarding the feasibility of nanodiamond to act as a cleaning/consolidation agent of papers and parchments. We carried out a series of treatments aiming to develop innovative approaches for de-acidification, cleaning and consolidation. Dispersions of nanodiamond have been used as de-acidification agents of ancient papers showing the ability to sensibly reduce the acidity of the paper without using any alkaline base. Similar dispersions have been used for cleaning processes and nanodiamond demonstrated an outstanding capability to clean ancient papers and parchments avoiding the use of any solvent and surfactant. Moreover interesting results were obtained by using nanodiamond as consolidation agent. In particular, artificial aging by UV exposition was appreciably contrasted when samples were preliminarily submitted to a treatment by nanodiamond. This outcome was demonstrated in papers and parchments by Raman spectroscopy analyses that evidenced the property of nanodiamond to be an excellent UV-scavenger.

Chitosan were selected as cellulose raw material to prepare coating solutions. The morphology, physical characteristics and chemical surface properties of the coatings are discussed in this paper. Different concentrations of chitosan (1–5% w/w) and deposited solution layer (0.5–1.00 μm) were used to obtain coated papers with thicknesses varying between 0.062–0.068 μm. The percentages of coating agent impregnated inside paper were also calculated from the apparent density of coated paper and the density of self-supported films prepared in the same conditions but deposited on an inert and smooth Plexiglass support. These percentages of impregnation ranged from 4.8 to 63.3% and increased as following: chitosan < chitosan nanoparticle. The resulting absorption rates indicated significant differences as a function of the nature of coating agent and confirmed results obtained for the percentage of impregnation. To explain differences in the behaviour of coating solutions, it was finally concluded that not only their viscosity must be taken into account but also their affinity toward paper.

Graphene is one atom thick two dimensional material with unusual mechanical, electrical, thermal and optical properties. Graphene, on larger scale is produced through reduction of graphene oxide which in turn is synthesized by chemical oxidation of graphite. Generally large area graphene oxide paper can be easily fabricated by solution filtration process, spin casting method and Langmuir-Blodgett assembly. In present study graphene oxide was synthesized by modified Hummers method. Free standing graphene oxide paper (GOP) was developed by simple drying of graphene oxide suspended in water followed by reduction by thermal treatment to synthesize free standing conducting graphene paper (Thermally Reduced Graphene Paper, TRGP). Thermal reduction was carried out for 30, 60, 90 and 120min and samples referred as TRGP_30, TRGP_60, TRGP_90 and TRGP_120 respectively. XRD results show decrease in inter layer spacing (d002) from 0.87 nm to ∼0.35 nm after reduction of GO paper. This shows gradual removal of oxygen fu...

Paper-based PbS photodetector sensitive in the visible spectrum is reported. Nanocrystalline PbS-on-paper devices are fabricated by a spin coating method on white paper (300 GSM) from a methanolic precursor solution. Photodetector cells of gap 0.2 cm and length 0.5 cm are prepared by drawing contacts by monolithic cretacolor 8B pencil. X-ray diffractometer confirmed the deposition of nanocrystalline PbS films with 14 nm crystallites. The SEM illustrated the uniform coating of nanocrystalline PbS thin films on cellulose fibres of papers having an average thickness of fibres are 10 µm. The linear J-V characteristics in dark and under illumination of light using graphite trace on nanocrystalline PbS-on-paper shows good ohmic contact. The resistivity of pencil trace is 30 Ω·cm. Spectral response measurements of photodetector reveal the excellent sensitivity from 400 to 700 nm with a peak at 550 nm. The best responsivity anddetectivity are 0.7 A/W and 1.4 × 1012 Jones respectively. These paper-based low-cost photodetectors devices have fast photoresponse and recovery without baseline deviation.

Here, we presented a novel, cost effective approach to fabricate flexible piezoelectric nanogenerator (NG) consisting of ZnS nanowires (NWs) grown upon cellulose. An output voltage of 4 V is generated from the nanocomposite paper (NC-paper) based NG. Subsequently, it has the capability to power Light Emitting Diode (LED) and charging up capacitor. The corresponding energy stored in the capacitor (1 µF) is 16 µJ. Thus, the fabricated NC-paper based NG can be used for smart textile structures, wearable and self-powered nanodevices.

Jute fibers are an environmental friendly natural fiber which can be used as good alternatives in the reinforcement of composite materials. The physical and mechanical properties of jute fiber are studied. The humidification cum heat treatment is carried out for the jute fiber. The tensile strength measurement was made for the untreated and humidification cum heat treated bundle jute fiber. The tensile strength of untreated and treated bundle jute fibers are 71.7 ± 9.5 MPa and 104.9 ± 8.8MPa respectively. A 45% increase in tensile strength is noticed. The structural organisation in the untreated and treated jute fiber is studied by X-ray fibre diffraction. The tensile strength measurement is carried out for the composite of Paper-Tamarind seed gum and Paper-Tamarind seed gum - Jute fiber and their measured tensile strength are 4.3 ± 0.5 MPa and 6.1 ± 1.2 MPa respectively. The enhancement in tensile strength for Paper-Tamarind seed gum - Jute fiber composite is observed. The environmental friendly biocomposite bags prepared are: Paper-Tamarind seed gum - Jute fiber and Paper-Tamarind seed gum, which can withstand load of 9.0 kg and 6.0 kg respectively. An increase of 50% in the load bearing capacity is achieved by reinforcing jute fibre.

The commercial telecommunication system in future would explore the electromagnetic spectrum with higher frequency than used now, because it requires higher speed of transmission data. Using the millimeter waves (mmW) with frequency ranging from 30 to 300 GHz, such requirement could be fulfilled. The upcoming 5G cellular technology is expected to use frequency 30 GHz or higher. Then materials with a specific characteristic at the mmW range are interesting to be explored and investigated. Here, we report the synthesis process of graphene/TiO2 deposited on paper and their transmission characteristics to the electromagnetic energy at frequency 27-40 GHz (Ka-Band). The reduced graphene oxide (rGO) was synthesized by a modified Hummers method with introduction of microwave irradiation in the process. rGO and TiO2 were mixed in ethanol solution and deposited on the paper by a spraying technique. Transmission coefficient of electromagnetic wave energy at Ka-Band was measured by using the millimeter vector networ...

Soft plate‐like membranes find application e.g. as pill or paper coatings, bio‐filter membranes, and gas seals in food products. For these applications the integrity and the mechanical properties of the membrane are important. Mechanical properties of these products can be determined by stretching or bending tests, but such methods can damage these fragile products. We propose a rapid nondestructive acoustic method to estimate mechanical film characteristics with shear horizontal (in‐plane shear) waves. A 23 kHz, 1‐cycle square signal was excited into a thin foil with a piezoceramic pickup and received with an inductive pickup. The SNR (power) was 20 dB in 1 kHz –50 kHz bandwidth. This actuation‐detection scheme can be used to excite in‐plane longitudinal, shear and even elliptic waves in a thin foil. The method was validated by measuring in‐plane shear wave and longitudinal wave time‐of‐flight TOF at different actuator‐receiver separations and calculating the corresponding longitudinal and shear modulus. The samples were Mylar® sheet and coated paper. The anisotropy of MOE for Mylar sheet was close to the manufacturer specifications. For coated paper a maximum shear modulus anisotropy of 5% and a shear modulus dependence on temperature of 0.7 MPa/°C were found. Laser doppler vibrometry showed that the excited waves were confined in‐plane.

The Lawrence Berkeley National Laboratory (LBNL) has been developing sensors for the pulp and paper industry that use a magnetic field. The applications for magnetic sensors that have been studied include 1) sensors for the measurement of the water and ice content of wood chips entering the pulping mill, 2) sensors for measuring the water content and other constituents of the black liquor leaving the paper digester, and 3) sensors for measuring paper thickness and water content as the paper is being processed. These tasks can be done using nuclear magnetic resonance (NMR). The magnetic field used for doing the NMR can come from either permanent magnets or superconducting magnets. The choice of the magnet is dependent on a number of factors, which include the size of the sample and field strength needed to do the sensing task at hand. This paper describes some superconducting magnet options that can be used in the pulp and paper industry.

CdSe quantum dot has great potential in various applications especially for emitting devices. One example potential application of CdSe quantum dot is security label for anti-counterfeiting. In this work, we present a practical approach of security label on paper using one and two colors of colloidal CdSe quantum dot, which is used as stamping ink on various types of paper. Under ambient condition, quantum dot is almost invisible. The quantum dot security label can be revealed by detecting emission of quantum dot using photoluminescence and cnc machine. The recorded quantum dot emission intensity is then analyzed using home-made program to reveal quantum dot pattern stamp having the word ’RAHASIA’. We found that security label using quantum dot works well on several types of paper. The quantum dot patterns can survive several days and further treatment is required to protect the quantum dot. Oxidation of quantum dot that occurred during this experiment reduced the emission intensity of quantum dot patterns.

This paper presents the laboratory result on compaction characteristic for soft soil subgrade which was stabilized by using waste paper sludge ash (WPSA). The soft soil sample was collected from Banting Selangor, Malaysia named as Banting soft soil and classified as slightly sandy Clay with intermediate plasticity. Additive of WPSA is a finely waste product produced from the incinerated waste paper. In ASTM C618, this WPSA samples are categorized as Type-C fly ash due to the high free lime (CaO) content (>20%) and possesses some cementitious and pozzolanic, resulting in the self-cementing characteristics. Therefore no entire activators such as lime are required. Objectives of this study are to determine the dry density and moisture content of Banting soft soil stabilized by WPSA through the different energy and method of compaction and to determine the Atterberg limit properties of Banting soft soil stabilized using WPSA. Several percentage of WPSA (4%, 8%, 12% and 16%) was used to stabilize the soft soil...

We successfully developed a method utilizing colloidal CdSe nanocrystalline quantum dot for anti-counterfeiting label on a piece of glossy paper. We deposited numbers and lines patterns of toluene soluble CdSe quantum dot using rubber stamper on a glossy paper. The width of line pattern was about 1-2 mm with 1-2 mm separation between lines. It required less than one minute for deposited CdSe quantum dot on glossy paper to dry and become invisible by naked eyes. However, patterned quantum dot become visible using long-pass filter glasses upon excitation of UV lamp or blue laser. We characterized photoluminescence of line patterns of quantum dot, and we found that emission boundaries of line patterns were clearly observed. The error of line size and shape were mainly due to defect of the original stamper. The emission peak wavelength of CdSe quantum dot was 629 nm. The emission spectrum of deposited quantum dot has full width at half maximum (FWHM) of 30-40 nm. The spectra similarity between deposited quant...

Polyaniline thin film has been prepared on paper by aniline vapor deposition technique. Ferric chloride has been used as polymerizing agent in this approach. The prepared films were studied through electrical resistivity and optical properties measurements. The electrical resistivity of the polyaniline film shows significant temperature dependence. The resistance sharply falls with the increase in temperature. The optical absorbance measurements shows characteristics absorbance peak indicating the formation of conducting emeraldine salt form of polyaniline. The optical energy band gap of the film was calculated from the transmittance spectra. The optical energy band gap and electrical conductivity of the polyaniline film is well suited for their applications in electronic devices.

Recycled glass powder was added with ball clay and feldspar using ratio 90:5:5. The blend were mixed into different amount of paper fiber and cast into porous ceramic. Samples prepared with different compositions (2, 4, 6, 8, and 10 wt % of paper fiber) were heat treated at constant temperature (750 °C) for an hour. Samples with high percentage of paper fiber gave the largest pore size in the ceramic body, meanwhile lower percentage of paper fiber produced ceramic body with smaller pore size.

A recent technology has been introduced into the paper industry that makes possible to produce paper materials by replacing the cellulose fibres by a mineral powder, achieving a more environmentally friendly product compared with conventional paper. The purpose of this work is to determine the possibilities of an air-coupled ultrasonic technique to study this kind of new materials in order to develop an ultrasonic system useful for quality control for this industry. In particular, air-coupled ultrasonic spectroscopy is specially well suited to this kind of materials because of the fact that no coupling liquid and no direct contact with the sample is employed. A through transmission technique is employed and Fourier analysis is performed to obtain both magnitude and phase spectra of the transmission coefficient. Properties in the thickness direction as well as in the paper plane are investigated. Different paper grades (from 120 to 400 g/m2) provided by Terraskin have been studied. Very high attenuation coeficientes and very low propagation velocities (and hence elastic constant) are obtained, this can be explained by considering the large porosity of this material (about 50%) and the microstrucutre: solid grains in contact with a variable amount of polymeric resin partially filling the pore space.

The Young’s modulus of buckypaper (BP) was improved via the addition of carbon nanocoils (CNCs). The Young’s modulus was the highest when the added amount of CNCs of the mass of the bucky paper was 11.9%. It is likely that the improved Young’s modulus was due to the higher Young’s modulus of the CNCs, compared with the multi-walled carbon nanotube (MWCNT) bundles. The helical structure of the CNCs also contributed to the improvement in the Young’s modulus. In the BP containing CNCs, the CNCs were anchored in the MWCNT matrix with superior entanglement, and this effect improved the Young’s modulus of the BP.

Organic catalyst has recently been identified as the potential substitution for expensive platinum electrocatalyst for fuel cell application. Numerous studies have shown that the nitrogen-containing carbon nanotubes (N-CNT) can be synthesized through spray pyrolysis or floating chemical vapor deposition (CVD) technique using various type of organometallic as precursors. This paper presents the method of synthesis and the initial findings of the growth of N-CNT directly on carbon paper using a modified CVD technique. In this research, nickel (II) phthalocyanines (Ni-Pc) as precursor was dissolved in ethanol solvent, stirred and sonicated to become homogenized. The solution was poured into a bubbler and heated up to allow the mixture to vaporize. Subsequently, the solution vapor was flowed into the tubical reactor maintained at 900°C. Carbon paper sputtered with nickel nanoparticles was used as the substrate. The synthesized sample was examined through Field Emission Scanning Electron Microscopy (FESEM), At...

We verify simulation results indicating that carbon ion irradiation increases the stiffness of single wall carbon nanotube bucky paper (SWCNT). 4 MHz longitudinal and 15 MHz shear ultrasonic signals were transmitted by means of dry‐coupled acoustic horns through 40±4 μm thick samples and the time‐of‐flight (TOF) through the samples was measured. From the TOF the velocity of the wave was determined and the out‐of‐plane elastic and shear moduli were calculated. The nonlinearity parameter B/A for the irradiated and reference sample was measured. The results indicated a significant increase both in the shear modulus (90 %) and in the longitudinal modulus (69 %) for certain irradiation doses as predicted by simulations. In addition, a 36% increase in the acoustic nonlinearity parameter (B/A) was observed. The investigated fluence range was 1⋅1013 to 3⋅1014 cm−2.

For the paper industry, stiffness properties are an important parameter for producing more efficiently a fibrous material like paper. Some stiffness properties of paper webs can be obtained in a non‐contact fashion using two lasers. The authors have developed an automated laboratory laser‐ultrasonics instrument for paper, described here. The results of non‐contact laser generation and detection of ultrasound are also presented. The paper grades investigated were heavy grades like linerboard, as well as copy paper.

Acoustic emission experiments in paper, a disordered material, give evidence for power‐law probability distributions of statistical quantities as event energies or intervals. Two setups, usual mode I tensile tests and a nip‐in‐peel one have been studied in our work. In both cases, even using the same material, we observe “criticality”. This has wide implications for theories of statistical fracture.

An important material property in the paper industry is the anisotropic stiffness distribution due to the fibrous microstructure of paper. Ultrasonic methods offer a means of determining the stiffness of sheets of paper from the anisotropic propagation characteristics of elastic Lamb waves along the machine direction (MD) and the cross direction (CD). Currently, piezoelectric ultrasonic methods are employed in the industry to measure the elastic polar diagram of paper through multiple contacting measurements made in all directions. This paper describes a new approach utilizing the INEEL Laser Ultrasonic Camera to provide a complete image of the elastic waves traveling in all directions in the plane of the paper sheet. This approach is based on optical dynamic holographic methods that record the out of plane ultrasonic motion over the entire paper surface simultaneously without scanning. The full-field imaging technique offers great potential for increasing the speed of the measurement and it ultimately pr...

On-line measurement of material properties is a goal of many manufactures for production improvement and quality control. In the paper industry, the elastic stiffness of the paper web needs to be accurately measured and controlled online. Currently, contact ultrasonic methods are employed to measure the elastic constants of paper offline. Piezoelectric transducers are placed in contact with the paper surface to generate and detect plate wave modes, known as Lamb wave modes, in the paper in both the machine and cross directions. Laser ultrasonics offers a new approach to making elastic wave measurements that does not require contacting the paper web. A pulsed laser generates ultrasound in the paper by delivering a high intensity short impulse to the paper through thermoelastic expansion. An optical interferometer is used to demodulate the small phase modulation that the elastic wave produces on a continuous probe laser beam. Difficulty in applying this approach to online measurements of rapidly moving pape...

The mechanical and electrical properties of a bulk material made of single wall carbon nanotubes (SWNT) are, due to weak intermolecular interaction, several orders of magnitude lower than those of the individual molecules themselves. We studied the effect of gamma‐irradiation on SWNT paper in air and under vacuum. For samples irradiated in air, changes in Young modulus and electrical conductivity were observed with maximum value for a dose of 170 kGy. Under vacuum there was only a small effect of irradiation. Raman studies of irradiated samples showed defects formation. Same experiments done with graphite showed similar results. A likely explanation of the results is that cross‐links between nanotubes were induced by irradiation in air.

The production of activated carbon using heat from microwave processing for activation time was successfully conducted and its performance in treating textile dye effluent was observed through various factors such as phosphoric acid loading used, contact time, dosage of activated carbon and pH. Activated carbon with phosphoric acid loading of 60% shown highest BET surface area that was 213.52 m2/g however, it obtained least thermal stability. The result indicated that about 97.11% of dye from textile effluent can be removed in only 90 minutes of contact time at pH 3 with the use of 2.0 g of produced activated carbon. The production of activated carbon using microwave processing can be an alternative way for activation process using conventional furnace heating. The used of rubber wood sawdust as the raw material for activated carbon production can solve the waste issue from sawmill as an example.

Ligno-cellulosic biomass from sustainable sources has been used to produce light weight and high specific surface area (SSA) activated carbons (AC) for a multitude of applications; such as components in energy storage devices such as batteries and supercapacitors. While direct conversion from biomass has been studied heavily, such AC with relatively high surface area can be more effectively produced when leveraged as a co-product from a biorefinery. In this paper, we discuss the production of high specific surface area activated carbons from residual fiber (fiber remaining after extraction of C5-sugars) generated as part of a biorefinery. Our work showed that the AC produced from the residual fiber delivered an order of magnitude higher surface area than the one directly from corn pericarp fiber and soy hulls. These AC were evaluated as electrodes in electrical double layer capacitors for energy storage. These results, along with the benefits of using the residual fiber to produce AC, are highlighted in this paper.

Polybenzimidazole (PBI) was prepared as thin coatings on aluminium substrates at different final curing temperatures. Their tribological properties were tested at room temperature in comparison to coatings made of polyamideimide (PAI), using various test methods. The adhesion to the substrates was best for PBI processed at a final curing temperature of 280°C. This was also reflected in a better scratch resistance, whereby in all cases PBI was superior to PAI. The same was true for sliding wear of the coatings against smooth steel counterparts. Under abrasive wear against sand paper, the friction and wear values were lower for smaller abrasive grains, but no remarkable differences were visible between PBI and PAI, regardless of the curing temperature.Polybenzimidazole (PBI) was prepared as thin coatings on aluminium substrates at different final curing temperatures. Their tribological properties were tested at room temperature in comparison to coatings made of polyamideimide (PAI), using various test methods. The adhesion to the substrates was best for PBI processed at a final curing temperature of 280°C. This was also reflected in a better scratch resistance, whereby in all cases PBI was superior to PAI. The same was true for sliding wear of the coatings against smooth steel counterparts. Under abrasive wear against sand paper, the friction and wear values were lower for smaller abrasive grains, but no remarkable differences were visible between PBI and PAI, regardless of the curing temperature.

This paper describes the reaction mechanism to deposit pyrolytic carbon within porous body of char derived from oil palm empty fruit bunch (EFB) via an integrated pyrolysis-tar decomposition process, which employs chemical vapor infiltration method. This process was developed to produce a value-added EFB-derived char and to make EFB able to be utilized as a supplementary solid biofuel. The product, namely carbon-deposited char, was characterized in comparison with metallurgical coke breeze used in iron-steel industry.

Black liquor from paper pulp industry contains lignin and spent pulping chemical. Conventionally, it is combusted in a recovery boiler to utilize the heat energy for steam production and for power generation. The steam is utilized in the pulping process. To improve the efficiency of power generation, a gasification process is proposed to replace the combustion process. However, it is still under research and development stage. Concentrated black liquor fed to the recovery boiler or gasifier usually has a solid content about 60 – 80%. Therefore, significant amount of water is still in the liquor and may impact the combustion or gasification process. In this work, the drying rate and early stage of devolatilization of concentrated black liquor is studied using DTA/TGA equipment. The experiment will be conducted in nitrogen atmosphere from room temperature up to 300°C. The heating rates that are used are 5, 10, 20, and 30 °C/min. From the experimental data, the drying and devolatilization stages can be distinguished. In this study, the drying kinetic is modeled using five semi empirical model. The models can give good fitting with the experimental data. The second stage, or devolatilization, comprised of the evaporation of the remaining moisture together with pyrolysis reaction. The kinetic analysis of the devolatilization reaction is performed using Distributed Activation Energy Model (DAEM).

Cement plays a major role in the production of paver blocks. Cement manufacturing industries pollutes the surrounding areas. The main objective of this work is to reduce the use of cement in the concrete paver block by partial replacement with rice husk ash. An experimental investigation is conducted to analyze the compressive strength, water absorption and flexural strength of paver blocks with partial replacement of cement by rice husk ash dumped near Chengapalli, Tiruppur. Rice husk ash were collected from the dump yard and utilized for experimental investigation after doing the initial cleaning process and property study of material. Cement replacement with Rice husk ash were done in proportions of 10% 20%, 30%, 40% and 50% in volume of concrete. Various strength parameters like compressive strength, flexural strength and water absorption were determined. Weight of concrete blocks is considerably reduced with increase in the amount of rice husk ash.

Wastewater of the laterite hydrometallurgy process which still contains nickel more than 0.25 % and other metals. One method which able to treat wastewater is the electrocoagulation process. In this work, the electrocoagulation process using batch recycle methods has been successfully coagulated nickel and other metals from the wastewater of the laterite hydrometallurgy process. In this work, a tubular aluminum electrode was used in the electrocoagulation reactor. Sodium hydroxide is used to increase the pH of waste. Taguchi design of experiment has been used to analyze and optimize the electrocoagulation process using batch recycle methods. Taguchi analysis results show that the optimum conditions are at 21 of voltage, 5 of pH, 5 hours of time operation, and 0.53 liters/minute of flow rate.