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One of the relatively inexpensive alternative energy sources in terms of production and relatively environment friendly was the development of bioethanol from urban wastes that contain many lignocellulose such as paper waste. This study characterizes the composition of cellulose, hemicellulose and lignin in blank HVS paper, inked HVS and newspaper. The results showed the predominate cellulose (49-60 %) while the lignin concentration was very low due to the removal of colors (lignin) in the manufacturing process. The experiments continued with synthesis of bioethanol through Simultaneous Saccharification and Fermentation (SSF) process. A combination of enzymes (Cellulase + Cellobiase) in 1:1 weight ratio and Saccharomyces cerevisiae was used for hydrolysis and fermentation in the SSF process. Paper waste from newspapers, inked HVS, and empty HVS papers were used as raw materials. The initial pH of SSF in the column was at pH 5. Variation of enzyme concentration was carried at 0.2, 0.3 and 0.5 g. The SSF process was carried out at incubation time of 6, 12, 24, 36, 48, 72, and 96 hours. The ink affected the concentration of bioethanol produced. In this study, the best bioethanol content was produced by inked HVS and Newspapers at 0.5 grams of enzyme with a concentration of 1531 and 1111 ppm, respectively.

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.

Leachate wastewater from pulp and paper industry is known for containing various types of heavy metals such as Cd (Cadmium), Ba (Barium) and Cu (Cuprum). The existence of heavy metals that accumulates and eventually exceeds certain threshold concentrations will cause environmental pollution, therefore it is necessary to conduct wastewater treatment to eliminate or at least reduce the heavy metal content in industrial wastewater. One of the most commonly used wastewater treatment method is using adsorbent, this study uses adsorbent made from the mixture of clay, zeolite and activated carbon formed into ceramic balls with ± 0.5 cm diameter. The ratios of the mixture of clay, zeolite and activated carbon are 6:3:1; 6:2,5:1,5; 6:2:2; 6:1,5:2,5 and 6:1:3 with variations of contact time 30, 60, 90, 120 and 150 minutes. The most favorable concentration reduction of heavy metals occurred at the longest contact time of 150 minutes at 6:3:1 adsorbent ratio, Cd concentration decreases from 0.65 mg/L to 0.03 mg /L, Ba concentration decreases from 0.86 mg/L to 0.04 mg/L and Cu concentration is from 0.6 mg/L to 0.02 mg/L. These prove that the ceramic zeolite/carbon-ceramic composite adsorbent can be an alternative to treat wastewater containing heavy metals derived from the pulp and paper industry.

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.

Synthesis of C-Dots from waste paper has been successfully created. A total of 5 grams of waste paper is mixed with 40 mL aquades, 30 mL H2SO4 and 50 mL NaOH 2 M. A precursor solution is prepared by adding urea in 20 ml of material. Synthesis of C-Dots done by heating the precursor hydrothermally using a furnace with three conditions, namely with 1-4 grams of urea, 20-50 minutes of synthesis time, and 150-300°C of temperature. In a variation of urea and time, the temperature is controlled at 300°C. In a variation of the time and temperature, urea is controlled at 3 grams. In a variation of the urea and temperature, time is controlled for 30 minutes. The maximum absorption C-Dots generated on the various of amount urea, temperature, and synthesis time in the range of 360-600 nm. The width of the absorbance area was increased by adding 1-3 grams of urea and were decreased when urea is added 4 grams or more. The absorbance peaks of C-dots decreases with increasing temperature synthesis. Meanwhile, an increasing of synthesis time does not affect to the width of the absorbance spectra. It precisely causes decreasing of peaks of the absorbance spectra. The functional groups present on the surfaces of C-dots can be identified by the presence of specific peaks in their FTIR spectra, i.e. N–H, C=C, C–N, and C–C at various urea, N–H, C=O, C=C and C–O at temperature and synthesis time.Synthesis of C-Dots from waste paper has been successfully created. A total of 5 grams of waste paper is mixed with 40 mL aquades, 30 mL H2SO4 and 50 mL NaOH 2 M. A precursor solution is prepared by adding urea in 20 ml of material. Synthesis of C-Dots done by heating the precursor hydrothermally using a furnace with three conditions, namely with 1-4 grams of urea, 20-50 minutes of synthesis time, and 150-300°C of temperature. In a variation of urea and time, the temperature is controlled at 300°C. In a variation of the time and temperature, urea is controlled at 3 grams. In a variation of the urea and temperature, time is controlled for 30 minutes. The maximum absorption C-Dots generated on the various of amount urea, temperature, and synthesis time in the range of 360-600 nm. The width of the absorbance area was increased by adding 1-3 grams of urea and were decreased when urea is added 4 grams or more. The absorbance peaks of C-dots decreases with increasing temperature synthesis. Meanwhile, an increas...

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...

Principal Component Analysis (PCA) is a commonly used unsupervised exploratory analysis technique. It is also frequently used in dimensionality reduction. This preliminary paper investigates the feasibility of three variants of PCA, i.e. independent PCA (iPCA), sparse PCA (sPCA), and sparse independent PCA (siPCA) on forensic classification of paper based on their IR spectral data. After that, Linear Discriminant Analysis (LDA) models were built using the Principal Components (PCs) produced by the PCA and the three aforementioned variants. The performances of all these four LDA models, i.e. PCA-DA, iPCA-DA, sPCA-DA and siPCA-DA, were evaluated via leave-one-out cross-validation on the data set. The results obtained show that iPCA-DA and siPCA-DA are the most effective models with 100.0% classification accuracy. Then, the effectiveness of siPCA and iPCA models was evaluated based on posterior probability used for predictions of class membership that were derived from leave-one-out cross-validation. As a conclusion, siPCA is identified as the best classification model.

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.

ECF technology has been established itself as the most preferred process worldwide. Peroxide addition minimizes the effluent color. The study deals with the bleaching of Bamboo and Jute Cady pulps with chlorine and peroxide treatment and identification of various chlorophenolics compounds. The results show that quantity of the total chlorophenolic compounds formed decreases up to 54% in total chlorophenolic compound in the CEH effluent and the COD and color values are reduced by 35% and 33% respectively as E stage is changed to Ep stage in Bamboo pulp. And there is a reduction of 52% in total chlorophenolic compound in the CEH effluent when E stage is changed to Ep. and the COD and color values are reduced by 30% and 33% respectively as E stage is changed to Ep stage in Jute Cady pulp

Historians and librarians are interested in watermarks and mould surface patterns in historic papers, because they represent the “fingerprints” of antique papers. However, these features are usually covered or hidden by printing, writing or other media. Different techniques have been developed to extract the watermarks in the paper while avoiding interference from media on the paper. Beta radiography provides good results, but this method cannot be widely used because of radiation safety regulations and the long exposure times required due to weak isotope sources employed. In this work, two promising methods are compared which can be used to extract digital high-resolution images for paper watermarks and these are electron radiography and low energy X-ray radiography. For electron radiography a “sandwich” of a lead sheet, the paper object, and a film in a dark cassette, is formed and it is exposed at higher X-ray potentials (> 300 kV). The photoelectrons escaping from the lead sheet penetrate the paper and expose the film. After development, the film captures the watermark and mould surface pattern Images for the paper being investigated. These images are then digitized using an X-ray film digitizer. The film employed could potentially be replaced by a special type of imaging plate with a very thin protection layer to directly generate digital Images using computed radiography (CR). For the second method, a low energy X-ray source is used with the specimen paper placed on a digital detector array (DDA). This method directly generates a low energy digital radiography (DR) image. Both methods provide high quality images without interference from the printing media, and provide the potential to generate a “fingerprint” database for historical papers. There were nevertheless found to be differences in the images obtained using the two methods. The second method, using a low energy X-ray source, has the potential to be integrated in a portable device with a small footprint incorporating user safety requirements. Differences obtained using the two methods are shown and discussed.

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-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.

Keraton Kasepuhan Cirebon has collection of five old manuscripts of European origin from 19th century, and the former library of Faculty of Humanities Universitas Indonesia has collection of four old manuscripts of European paper origin from 19–20th centuries. The objectives of this study were to isolate and morphologically characterize fungi from nine old manuscripts of European origin. All manuscripts showed brown and black spots, and fungal spores on the surfaces. Observation by loop was carried out in the field to determine the type of paper and to detect biodeterioration of the manuscripts. Twenty-two fungal isolates were obtained by sterile cotton swab and the culture-dependent method on Dichloran Glycerol Agar (DG18). Detection of fungal deterioration on paper was investigated by using paper strip method with old paper of European origin on Czapek’s Dox Agar (CDA) without carbon source. The paper strips were inoculated with cell suspension at a concentration of approximately 1 × 107 cell/mL. Twenty fungal isolates were able to grow on the old paper strips indicating that the old manuscripts are liable to fungal degradation. The fungal isolates were xerophilic in nature. Morphological characterization described the fungal isolates in the genera of Aspergillus, Penicillium, and Eurotium. Three fungal isolates could not be described and were grouped as Mycelia sterilia. Basic local alignment search tool (BLAST)-based identification and phylogeny-based identification using the data set of internal transcribed spacer (ITS) sequences is required to determine the species identities of the fungal strains.

Keraton Kasepuhan Cirebon and the former library of Faculty of Humanities Universitas Indonesia have collections of old manuscripts of European paper origin from 19-20th centuries. This study investigated the cellulolytic and xerophilic characters of 22 fungal strains from nine deteriorated old manuscripts of European paper origin. Detection of cellulolytic fungi by using well diffusion method, modified Czapek’s Dox Agar (CDA) with 0.1% (w/v) carboxymethyl cellulose (CMC) as a sole carbon source, 0.2% (w/v) Congo red as a chromogenic dye, and cell suspension of approximately 1x107 cell/mL. Cellulolytic fungi formed clear zones around the fungal colonies due to the radial diffusion of the enzyme excreted to the medium. Detection of xerophilic fungi by using Dichloran glycerol Agar (DG18) which contained 18% glycerol to reduce water availability in the medium. Fifteen fungal strains have the ability to use derivative cellulose in CMC as a sole carbon source indicating that these strains possessed endoglucanase (CMCase) activity. The action of cellulolytic enzyme from fungi could dissolve cellulose fibers, or might discolor the paper. All the fungal strains were xerophiles, which indicated that they were able to grow in manuscripts, a condition of reduced water activity. Further studies are required to determine exoglucanase activity by using crystalline cellulose, and molecular identification by using internal transcribed spacer (ITS) sequences to determine the species identities of the fungal strains.

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.

Several approaches have been proposed to help researchers in retrieving relevant and useful information from the cyber-ocean of information. However, the approaches assumed the academic content to be easily accessible, which is not always the case considering the copyright restrictions. Different from the existing works, we proposed a collaborative approach that leverages public contextual metadata to personalize scholarly recommendations. Our proposed approach has the ability to recommend research papers to the individual researchers regardless of the researcher expertise and research field. As demonstrated using a freely accessible dataset, our proposed approach have shown significant improvements over another baseline method.

The impairment of the quality of water is a serious and rising issue globally. The extreme impairment cases often be the main reason to unbalanced human and ecosystem impacts. It causes a very limit of resources for quality consumption and the manufacturing of food, domestic use and also damaging ecosystems. It is expected that various factors combination makes conditions suitable for terrible water quality. The aim is to find the suitable water quality parameter that is relate to extreme cases of water quality. Extreme value theory will be introduce as statistical tools for analyzing extreme data and predict future extreme occurrences based on return level.

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...

An algorithm for constructing super-large semantic networks has been developed in current work. Algorithm was tested using the “Cosmos” category of the Internet encyclopedia “Wikipedia” as an example. During the implementation, a parser for the syntax analysis of Wikipedia pages was developed. A graph based on list of articles and categories was formed. On the basis of the obtained graph analysis, algorithms for finding domains of high connectivity in a graph were proposed and tested. Algorithms for constructing a domain based on the number of links and the number of articles in the current subject area is considered. The shortcomings of these algorithms are shown and explained, an algorithm is developed on their joint use. The possibility of applying a combined algorithm for obtaining the final domain is shown. The problem of instability of the received domain was discovered when starting an algorithm from two neighboring vertices related to the domain.

The infrared (IR) spectra of different white copy paper types tend to appear indifferent. Discrimination between white copy papers could lead to the solution of forgery cases. In this preliminary study, three varieties of white paper were purchased from local stationery shops in Kuala Lumpur, Malaysia. The papers were classified according to their manufacturers using Partial Least Squares-Discriminant Analysis (PLS-DA) and sparse PLS-DA (sPLS-DA) models. The error rate for the two models on the training and the test data sets were estimated and compared. Results show that the performance of the two models are comparable. By including the first six latent variables in both models, classification accuracy as high as 100% can be achieved.

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...

Selection of the most significant variables, i.e. the wavenumber, from an infrared (IR) spectrum is always difficult to be achieved. In this preliminary paper, the feasibility of genetic algorithms (GA) in identifying most informative wavenumbers from 150 IR spectra of papers was investigated. The list of selected wavenumbers was then employed in Linear Discriminant Analysis (LDA). GA procedure was repeated 30 times to get different lists of variables. Then the performances of LDA models were estimated via leave-one-out cross-validation. A total of six to eight wavenumbers were identified to be valuable variables in the GA procedures. All the 30 LDA models achieve correct classification rates between 97.3% to 100.0%. Therefore the GA-LDA model could be a suitable tool for differentiating white papers that appeared to be highly similar in their IR fingerprints.

Infrared (IR) spectral data are always influenced by undesired random and systematic variations. As such, pre-processing of spectral data is normally required before chemometric modeling. Two most widely used pre-processing techniques, i.e. scatter-correction methods and spectral derivatives, were used to pre-process 150 IR spectral data of paper. The algorithms investigated in this preliminary study are Standard Normal Variate (SNV), Multiplicative Scatter Correction (MSC), Savitzky-Golay (SG) and Gap-Segment (GS). The visual examination of the clustering among three studied varieties of paper, i.e. IK Yellow, One Paper and Save Pack, is accomplished via Principal Component Analysis (PCA). Overall, separation of the three varieties of paper is greatly enhanced after pre-processing. The most significant improvement is obtained with pre-processing via 1st derivative using SG algorithms.

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.

Pineapple has been known for a number of beneficial biological activities such as anti-oxidative and anti-browning. Some of these bioactivities are contributed by enzymatic complex in pineapple and it can be found mainly in the skin extracted pineapple juice. The purpose of this study is to determine the effect of the pineapple juice as a pulping and bleaching agent in the process of papermaking. During pulping of pineapple leaf fibre, the mixture of pineapple juice/water was added together with a constant amount of 3% Sodium Hydroxide (NaOH) at various concentration of pineapple juice (0%, 20%, 40%, 60% and 80%). Pineapple leaf fibre (PALF) was soaked several times with pineapple juice and NaOH during pulping and bleaching process in order to get the optimum results of the paper sheet obtained. The mechanical and physical properties of paper sheet were studied by measuring its tensile strength, tear resistance and water absorption. Comparatively, paper sheet produced from NaOH pulping shows better mechanical and physical properties than the mixture pulping of NaOH and pineapple juice. Additionally, pulping with higher concentration of pineapple juice tends to give long fibre rather than short fibre. Overall, the results of this study can be used as an alternative way in the production of paper and it also opens a door to utilize wisely the waste residue of pineapple in other sectors.