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Surface-enhanced Raman scattering (SERS), a simple, highly sensitive, and fast analytical method can be used to detect corrosion components on the surface of bronze ware, a difficult problem. The silver mirror reaction is suggested for depositing precious metal nanoparticles on cellulose filter paper in order to create a quick, easy, and low-cost approach for creating SERS substrates. After an 8-minute deposition time, optical microscopy and scanning electron microscopy (SEM) revealed a uniform dispersion of precious metals on cellulose filter paper. To examine the SERS characteristics of the substrate, copper chloride oxide, the main ingredient in the damaging rust of trace bronze ware, was used as the probe molecule. The findings show that cellulose filter paper with a uniform distribution of precious metals achieves the best SERS performance. The flexible substrate enables effective trace analysis of damaging rust on bronze surfaces.

In order to reasonably evaluate the effectiveness of UHF sensor arrangement in online monitoring of partial discharge of bushing, it is necessary to study the electromagnetic wave propagation characteristics of partial discharge UHF in the bushing. In this paper, a three-dimensional model of a real transformer bushing is established, the XFDTD software is used to simulate the raised seat defects and internal capacitive core defects of the bushing, field strength sensors are arranged at different locations inside and outside the bushing, and the propagation process of partial discharge UHF signals leaking from the oil-paper insulated bushing to the external free space is simulated and analyzed. The results show that the time difference between the signals received by the field strength sensors at different locations is not significant and can be neglected in practice. The partial discharge electromagnetic wave signal generated by the bushing elevated seat defect leaks from the upper porcelain sleeve to the external space, and the leaked electromagnetic wave energy is mainly gathered at the upper and lower ends of the upper porcelain sleeve. The partially discharged electromagnetic signal at the capacitor core inside the bushing will propagate along the coaxial waveguide structure formed between the capacitor screens towards the two ends of the capacitor core, the downward propagating electromagnetic wave energy is confined within the elevated seat, the upward propagating electromagnetic wave energy propagates from the top of the upper porcelain bushing to the external space, the leaked electromagnetic wave energy is mainly concentrated at the top of the upper porcelain bushing. The simulation results provide ideas for optimizing the arrangement of external antenna sensors for UHF detection of partial discharges in transformer oil-paper insulated bushings.

Light-reflecting characteristics play a crucial role in optically rewritable liquid crystal display (electronic paper). By using a special optimizer software, light-reflecting characteristics of the twisted nematic cell were calculated. The achieved values of the normalized reflection coefficients range within ∼ 0.03 - 0.43, which is comparable or better than other commercial technologies. The calculated contrast ratio of the device is 10 : 1. A 2D image, which can be displayed on the electronic paper was obtained. Comparison of the simulated background color and contrast ratio is very similar with the results, which were obtained in experimental cells of other studies. Our calculations indicate that angular dependence of the reflectance coefficient is almost uniform within a wide range of viewing angles.

This paper reports the use of non destructive, microstrip patch antenna as paper moisture sensor. Microstrip patch antenna is designed to resonate at 2.4GHz. This design is simulated and fabricated on copper clad type FR4 (εr= 4.4) having thickness of 1.6mm. Patch dimension are 27mm × 30mm and substrate dimension is 63mm × 60mm. The microstrip transmission line is used to provide excitation for the antenna. This design for microstrip patch antenna after fabrication showed a resonance at 2.38 GHz on vector network analyzer at S11=-19.38dB with impedance =49Ω. The variations in frequency in relation with water content in the paper is measured using Vector Network Analyzer by placing wet paper on the patch antenna. Moisture content in the paper was found out by taking wet weight and dry weight of the paper. The model of the wet paper is recommended primarily on the basis of water-dry paper reactions, along with the thickness and surface roughness explaining tendencies of the sensitivity graphs. Paper samples of 13 different types, with different GSM values and thicknesses, havingdimensions same as that of the substrate were tested. From the results it is observed that as the moisture content in the paper increases the frequency decreases. The change in frequency with respect to the moisture content is seen to have quadratic relation with moisture. The variations in the frequency are fitted in the form of equations. The calculated %Mwet indicates an error around ±0-4% in the calculated value as compared to the actual value. The response of sensor is almost linear with respect to the references but the coefficients depend non-linearly with the paper dimension.

This experiment initially explored the clean production process of nanocellulose fibrils (NFC) using commercial softwood pulp as raw materials, and selected appropriate biological enzyme pretreatment to prepare NFC1 with a higher concentration. Compared with NFC2 obtained by TEMPO oxidation method, it is found that the diameter of NFC1 obtained by enzymatic pretreatment method (10-30nm) is similar to that of NFC2 (20-30nm). But the length of NFC1 (1-4μm) is much longer than the length of NFC2 (400-600nm). In addition, the influence of two kinds of NFC on the physical strength of paper is also explored. Experimental results show that: NFC1 is better than NFC2 in enhancing the physical strength of paper. And when cationic starch and NFC act synergistically, the enhancement effect is obviously better than using NFC alone or cationic starch alone. When the addition amount of NFC1 is (1.5±0.5)%, the tensile index, burst index, and tear index of the resulting paper increase by (43±3)%, (55±1)%, (37±2), respectively %. When the amount of NFC2 added is (1.5±0.5)%, the paper tensile index is (29±2)%. When the amount of NFC2 added is about (3±1)%, the paper’s bursting index and tearing index growth rate are (29±1)% and (33±1)% respectively.

Determining the optimal clusters can be regarded as a grouping problem that has produced many cluster approach methods in various studies. Each method has provisions that can solve one or more grouping problems in generating information from data set with a number of k being tested. The advantages and disadvantages of each method actually complement to each other in solving the grouping problems. This paper aims to describe the performance of cluster approach methods in determining the optimal clusters through a review by paying attention to the criteria of the problem which is an obstacle to the grouping problem. The results of this review are expected to be a reference for developing the new optimal cluster approach method through possible combinatorial optimization.

When partial discharge occurs in the power transformer, the arc can further develop on the oil-paper interface between high and low potentials, and then form a path, resulting in large-area flashover. This will lead to a wide range of insulation damage, insulation failure, equipment shutdown and even large-scale economic losses. For the insulation damage caused by surface discharge of oil paper insulation, relevant scientific research institutions have carried out a large number of experimental studies. However, limited by the test conditions, the research focuses on the small-size model below 50mm, and mostly adopts the test device of uneven electric field. The research on the “large-size“ of the same scale inside the transformer is still blank. In this study, an oil-paper insulation surface discharge test platform with a large size of 50-150mm is built, the electric field conditions at the oil paper interface during the operation of transformers in engineering are simulated, and the surface discharge test of insulating paperboard is carried out by taking the same sample processing means as the engineering. Combined with the test results, a typical design optimization case of setting along surface corner ring to improve the allowable value of along surface discharge field and enhance along surface insulation margin is proposed. It lays a foundation for enriching the transformer oil-paper insulation design parameter system and improving the transformer oil paper insulation performance and operation reliability.

A tapered glass capillary MeV-ion microbeam setup, previously home-developed, was recently upgraded. To check the upgraded microbeam system quality and accuracy, microbeam particle induced X-ray emission (PIXE) mapping of potassium permanganate (KMnO4) solution diffusion in filter paper was carried out to study how the measured solvent diffusion followed the diffusion laws. Two initial boundary conditions and diffusion situations were applied: (1) the paper vertically placed in air with one end soaked in the solution for ten minutes, and (2) the paper horizontally placed on water with the solution dropped at a side of the paper for three minutes. 2-MeV-proton microbeam PIXE analyzed the paper pixel by pixel and the GUPIXWIN software was used to calculate the elemental concentrations in the pixels to map the concentration changes in the pixels as a function of the distance between the pixel position and the origin of the solution. The resulting maps demonstrated the solution diffusions in two cases indeed well following the diffusion laws, a steady-state diffusion dominated process where the elemental concentration was a linear function with the distance but joined by other non-diffusion factors for case 1, and a pure diffusion process where the elemental concentration was an error function with the distance for case 2.

The traditional Chinese folk paper-cutting art has a long history. It is a traditional folk art form created by working people to satisfy their spiritual and material pursuits. It originates from life and returns to life. With the pace of the times, folk paper-cutting has undergone an innovative transformation and development through the interweaving, penetration and integration of contemporary design concepts. Through the combination of network big data, it provides a large number of references for modern graphic design decoration and function combination, graphic context inheritance, color language, modeling language, etc.

Detection and identification of potassium ion (K+) level in urine is essential for diagnosis of several deseases or for guiding treatments. We have developed a simple, rapid, low cost and naked-eye quantitative method for K+ analysis in urine using a paper-based colorimetric array test strip. The array comprised three sensing elements printed using a wax-printing technique and filled with different amounts of crown ether (4-aminodibenzo-18-crown-6) modified gold nanoparticles (AuNPs). The detection is achieved by measuring the color change (from red to violet) when AuNPs aggregated following crown ether-K+ complexation. Furthermore, the detection sensitivity could be controlled by changing the amount of the crown ether. The strip sensor array based on crown ether modified AuNPs successfully detected K+ level in the ranges of 5-1000 µM by naked eye. Thus, the developed sensor is very simple yet has a potential to be of real use in detecting K+ in real urine samples.

A method for detecting paper’s surface defects is proposed, which is based on mathematical morphology algorithm and computer vision technique. Firstly, the mean filtering and wavelet denoising in image pre-processing are used to eliminate the image noise, and wavelet analysis can achieve image enhancement and increase the contrast between the target area and the background. And then, an improved threshold Canny operator is used to segment the image to extract the complete scratch line and other defect edges. Finally, the target region features are coloured by mathematical morphology processing. The method’s stimulating result is verified in the Matlab software, from which we can conclude that the method’s detecting effect is very effective.

Coconut fronds are part of a coconut tree that has been rarely used while the amount is abundant. Therefore, there is a concern of how to more utilize coconut fronds. Coconut fronds can be used as raw material for making art paper because it has good amount of fiber and cellulose. The utilization of coconut fronds for making art paper can minimize the coconut fronds waste. Additionally, it also has an impact on forest conservation, since most of raw materials for paper pulp are coming from woods in the forest. The objective of this study is to utilize coconut fronds as agricultural solid waste as raw material for making art paper. The method used to make the paper is chemical pulp, which including pulping and bleaching, as well as art paper molding. The prepared art paper was then characterized by tensile strength test, strength test stretch and grammature. The art paper samples that have been prepared met the minimum SNI grammature of 100 g/m2. While, for the best tensile resistance test was about 19,800 for sample 30/75. Meanwhile, the best stretch resistance test was 0.955 for sample 60/75.

Sensors with accurate detection of various liquids have attracted increasing research interests in environmental protection and organic solvents transporation. In this paper, liquid sensor based on laser induced graphene paper (LIGP) was proposed, and successfully used for the rapid detection of micro volume liquid. The processing-structure-property relationship was systemically studied. LIGPs with different morphologies exhibited various sensitivities and showed good reproducibility and fast response. The response mechanism related to contact resistance between some adjacent graphene flakes/fibers was proposed. With the key findings, LIGP liquid sensors can be used as the detector for accurate identification of different solvents and have great potential in monitoring organic solvent leakages of pipelines and fabrication of smart anti-corrosion composite structures.

Kojic acid is an antioxidant used by the cosmetics industry but the excessive usage of kojic acid may cause harm to human health. Therefore, it is important to detect the content of kojic acid in cosmetic products. In this work, the low-cost and simple paper-based analytical devices (μPADs) based on double-sided adhesive tape were developed for the colorimetric detection of kojic acid. The μPADs were fabricated by dissolving double-sided adhesive tape in toluene and then making the patterned adhesive tape penetrate into the filer paper. Ferric nitrate was used as the reagent to react with kojic acid, and the product of their chelating reaction caused the color change from colorless to orange-red. The ImageJ software was used to analyze the color intensity and the corresponding correction curve was determined. The μPADs for the detection of kojic acid exhibited a wide linear range (0.05 - 4 mM) and the detectable limit was 0.05 mM. The good selectivity and reproducibility were also demonstrated.

Paper and pulp industry factory is a factory that contributes to national economic development because paper needs per year can reach 100 million tons. But not only the positive impact is given, the negative impact is present because it produces considerable waste. The paper industry’s liquid waste is one of the many wastes containing a lot of metal, for example hexavalent Pb and Cr heavy metals. It is necessary to reduce according to government standards in order to reduce negative impacts on the environment. One way to reduce Pb and Cr levels is ion exchange using cation resin 500 ml paper liquid waste mixed with cation resin at a volume and weight ratio of 10: 0.0017; 10: 0,0034; 10: 0,0068; 10: 0,0136; and 10: 0.0272. Mixing is done with a 190 rpm stirrer motor and the variation of time used is 10, 20, 30, 40, and 50 minutes. The best treatment at a ratio of 10: 0.0272 with a time of 20 minutes. The results obtained by Pb and Cr decreased by 94% from the initial level.

Lignin is one of the constituent component of wood, but the presence of lignin can be a nuisance in the paper making process. Lignin will reduce the physical and optical properties of paper. The objctive of this study is to determine the advantages of lignin-kraft and its impact to modify cationic starch on the physical properties of fine paper. The study was conducted in steps. In the first step extraction was carried out to obtain the kraft-lignin, by using two extraction methode that is acid extraction with termal and acid extraction with centrifuge. Kraft-lignin was tested from both methods, the optimum test value will be continued at the coocking stage into resin-lignin. Resin-lignin will be a modified compound with level addition 3% and 6% of the dry weigh of cationic starch, then it will be applied to the handsheet with 13 variation, namely blank;, DS existing (2 Kg/TP, 4 Kg/Tp, dan 6 Kg/TP), cationic starch emultion + resin-lignin 6%, cationic starch substitution + resin-lignin 3%, and cationic starch substitution + resin-lignin 6%. Variation of cationic starch substitution + resin-lignin 6% at level addition 6 Kg/TP indicates the best value of physical strength. Especially on tensile strenght, wet tensile strenght, bursting, tearing, dan internal bonding value.

Most papers are made from virgin wood-based pulp of hardwood sources but recently, softwood have received enormous attention as alternative to hard wood because the hardwood takes a significant number of years to mature enough for use in the pulp and paper industry unlike softwood which are majorly annual plants. The annual crop in focus in this work is the yellow open-pollinated variety of corn which generates tons of waste at harvest. A novel attempt is made to ascertain the viability of corn sheaths as raw material for the pulp and paper industry by carrying out a comprehensive analysis on the pulp and paper made from the pulp. The sheaths were dried, shred and cut into pieces suitable for the digester and the pulps obtained were analysed for physico-chemical properties. Hand sheets were also made using the generated pulp and its physico-mechanical properties were analysed. Results obtained were compared with pulp from corn husks from other parts of the country, three Nigerian fibre sources – silk cotton, bagasse and rice straw and other foreign non-wood sources and found to be of competitive properties. Pulp properties of Lignin content, ash content, cellulose, hot and cold water solubility of the fibres were 13.72 ± 1.21%, 1.27 ± 0.23%, 53.26 ± 1.11%, 15.20 ± 2.11 and 6.14 ± 2.43 respectively while the mechanical properties of paper from the pulp were Bursting strength (282.163 KPa m2/g), Tear strength (146.119), Tensile strength (257.6N/m) and Tensile Index (3.9Nm/g). It was found that in all properties, the corn sheath was better than the rice straw fibers but not as good as the silk cotton and bagasse fibers. However, the corn sheath has been identified, as a viable raw material for the pulp and paper industry in Nigeria.

Paper is the final product resulted from compression of fiber suspension of cellulose pulp, which is derived from wood or non-woody material. In this study, paper was made from mixture of pineapple leaves and sugarcane bagasse pulp (P:S, 100:0%, 80:20%, 60:40%, 40:60%, 20:80%, and 0:100%) at varying cooking liquor or NaOH concentration (1.5% and 3%) using semi-mechanical soda pulping method. Pulp characterisation (kappa number, tensile and tearing strength) was further carried out to ensure a stable pulp and paper quality. Results showed that the highest tensile strength of 6,709 kN was obtained at pineapple leaves and sugarcane bagasse pulp composition of 100:0% and NaOH 3%, whereas the highest tearing strength (1730,13 mN) was observed at the P:S of 40:60% with similar concentration of NaOH. The lowest kappa number (6,182) was also obtained at P:S of 0:100% and 3% NaOH. The pulp characterisation values have fullfil SNI No. 6519:2016 quality standard for plastic laminated paper.

Utilization of agro-based fibre for paper making has been the subject of interest in order to expand the usage of renewable resources as well as reduced the dependence on wood pulp. As one of the major countries in palm oil production, some of the waste from the oil palm plantation like the oil palm fronds, empty fruit bunches, and its leaf is a potential source of non-wood industry which can be used as raw material in the paper industry manufacture. This study was done to examine the potential of palm leaves to be used as a raw material of non-wood resources in the papermaking industry. In this study, sodium hydroxide (NaOH) pulping and process was employed to investigate the effectiveness of lignin removal for good fibre production. The concentration of the pulping agent was fixed at 7% at treatment of 1-7 hours to investigate the best condition for defibrillation of the cellulose fibre. Based on this study, it was found that the soda pulping produces fibre that can be molded into paper sheet without any binding agent. The morphology of the fibre observed under Scanning Electron Microscopy (SEM) shows that, soda pulping fiber consist of individual micro fibrils that are well separated. Both tensile strength and tear index gives highest value at 1.93 kg/cm2 and 37 Nm2/kg respectively at 7 hours treatment time. his reflects that lignin removal effectively occurred in soda pulping. Tensile strength found to increases with treatment time and both tensile strength and tear index of the paper falls within the value comparable to commerical non-wood paper. The paper produced has rough surface and has the potential to be develop for craft paper.

The focus of this study is to analyze whether there are differences in the difficulty index of items if the same items are displayed with the Paper Based Test (PBT) model and the Computer-Based Testing (CBT) model. The PBT and CBT models have the same paradigm of measuring estimated abilities but have differences in the context and feel aspects. These differences include the number of items in the range of eyesight, use of tools, how to work on items, basic knowledge needs about computer operations, and habit factors. These differences can affect the results of estimating the ability of test participants. This study uses development methods and quantitative methods. Development methods are used to develop package items and CBT software. Two groups of respondents were used with equal ability to work on the same question package. One group uses the PBT model, and the other group uses CBT so that the response choices are obtained in each test model. The results of the respondent’s answer choices were then analyzed by the ITEMAN software to get the item difficulty index. The item difficulty index of each model was tested statistically using SPSS software, whether there was a significant average difference between the two test models. From the results of the study and analysis in classical theory, it can be concluded that statistically there are differences in the average difficulty index of the items if the same item is displayed with the PBT and CBT models. It was found that the items displayed with the PBT model had a more difficult tendency than when displayed with the CBT model.