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Low-velocity impact tests of unfilled and foam-filled Kraft paper honeycomb are carried out to investigate the effect of foam, indenter size and location of indentation on maximum or peak force and energy absorption capability. In this study, three indenter sizes (10mm, 12mm, 15mm) and three different locations of indentation (vertical edge, double wall and single wall) were used and compared. The test results show that the foam is given a significant increment of peak force and specific energy absorption to the honeycomb structure subjected to indentation load. The peak force and energy absorption capability also effected by indenter size which due to the contact area of indentation. As for the location of indentation, vertical edge gives highest peak force and energy absorption by the fact that vertical edge is the intersection of three walls of honeycomb cell.

This paper introduces a new type of moisturizing paper, which makes the material have a stronger moisturizing effect than ordinary transfer paper through the water-based double-layer coating process. At the same time, the paper has a stronger degradation capacity than plastic film paper, more in line with environmental protection requirements. Through the paper printing machine adaptability verification, the paper has easier processing and stronger printing performance. The development and application of this moistening material is a major innovation in the field of moistening packaging materials research.

For a long time, the daily paper and carbon ink have been used for writing and painting. With the development of the electronic technology, they are expected to play new roles in electronic devices. Herein, combining the unique characteristics of the paper (rough surface, hydrophilicity) and carbon ink (conductivity), this work rationally proposed two low-cost, eco-friendly, flexible, multifunctional pressure and humidity sensors. The results show that as-fabricated paper-based (PB) pressure sensor has a good sensitivity of 0.614 kPa−1 in the pressure range of 0–6 kPa. The PB humidity sensor has a large response of ∼2120 (current ratio at 91.5% relative humidity (RH) and 0% RH). The PB pressure sensor is proven to be useful for multiple pressure related contact detections, and the PB humidity sensor can be used for many humidity related non-contact detections. Interestingly, combining the different detecting modes of pressure and humidity sensors, some same detecting functions (e.g. switch, respiratory frequency and speech recognition) are realized from contact to non-contact using PB pressure and humidity sensors, which greatly enhance the wearable comfort. Compared with previous reports, this work demonstrates a much simpler approach without expensive raw materials, toxic reagents and high temperature treatment to achieve outstanding sensing performances of the multifunctional pressure and humidity sensors.

Oil paper insulating bushing is widely used in 500 kV and above power transformers. In order to quantitatively study the influence of water content on the dielectric spectrum of oil paper insulated bushing, HN model was used to fit and analyze the dielectric spectrum parameters of oil paper insulated bushing with different water content. The experimental results show that HN model can be used to evaluate the wettability of oil paper insulation, but the evaluation range of wettability of oil paper bushing with complex insulation structure is not clear. The results show that the relaxation time constant decreases with the increase of water content, and has a linear relationship with the change of water content; the difference between high frequency dielectric constant and static dielectric constant increases with the increase of water content.

Paper honeycomb sandwich plate is often used as transport packaging for the good cushioning and vibration isolation properties. However, the change of relative humidity has a great influence on the vibration performance of paper honeycomb sandwich plate because of its strong water vapor absorbing characteristics. In order to avoid the system resonance and reduce the product vibration damage, the main resonance frequencies for the paper honeycomb packaging system were evaluated by the sinusoidal vibration tests, further the effects of relative humidity, static compression stress, and the geometric parameters of honeycomb core on the main resonance frequencies were investigated. The results show that the main resonance frequency decreases with the increase of relative humidity, static compression stress, honeycomb cell length, and plate thickness.

The recent advancements in smart materials, processing techniques, and sensing technology have pervasive to the development of the modern era of flexible electronic systems. Flexible pressure and strain sensors with multi-functional sensing capabilities have gained significant interest as they have potential applications in human motion detection, physiological signal monitoring, flexible robotics, electronic skin, and smart displays. Hence this puts forward a higher requirement to develop highly sensitive, low cost and high-performance electromechanical sensors. Herein, we demonstrate the fabrication of solution-processed MoSSe/paper-based flexible Pressure and strain sensor with PDMS encapsulation using facile hydrothermal and vacuum filtration method with merits of low cost, large-area deposition, high scalability, and superior sensing performance. The fabricated device exhibited a very high sensitivity of 108.09 kPa−1 and a gauge factor of 27.57 with good reproducibility, stability, and resilience for 1200 bending cycles which indicates the robustness of the device. The enhanced sensing efficiency can be accounted for the excellent piezoelectric property and the pressure, strain-induced bandgap modulation observed in Janus MoSSe which arises due to the loss of symmetry in the crystal lattice. The sensors were utilized for real-time applications for the detection of various human physiological signals by integrating them into body parts, breath sensing, handwriting recognition, unknown shape detection, and pressure mapping. This successful demonstration of high performance, low cost, and large area deposited paper-based pressure and strain sensors, opens up new opportunities for far-reaching applications in health care, security, smart systems, and robotics.

In this study, three parameters, namely the density of Kraft paper, the thickness of cell wall and the cell size of honeycomb were evaluated. A statistical analysis was performed to investigate the effect of the parameters on the specific compression strength(SCS) and specific energy absorption (SEA) of Kraft paper honeycomb. Based on the design of experiment, 27 configuration of Kraft paper honeycomb with different cell sizes (10mm, 15mm, 20mm), thicknesses of cell wall (1ply, 2ply, 3ply) and paper densities (80gsm, 120gsm, 175gsm) are subjected to quasi static compression loading. An analysis of variance (ANOVA) was used to examine the effect of each parameters and to obtain the optimum configuration of Kraft paper honeycomb. As a result, the thickness of cell wall shows as the most prominent parameter for specific energy absorption and specific compression strength. Meanwhile, the Kraft paper honeycomb with density 175gsm, 3 ply thickness of paper and 10mm cell size of honeycomb shows the optimum configuration with 724.80 J/kg of SEA and 9.35 MPa/kg of SCS.

In this review paper we have done a detailed study on the different types of material that we can use for the manufacturing of alloy wheels in order to meet the need of the market. During this project we studied the fatigue analysis of aluminium, magnesium, and titanium alloy wheels on the basis of their deformation under load, maximum shear stress of materials, and equivalent stress of the materials. Also we studied the different methods of production of alloy wheels.

Iranian Light Source Facility (ILSF) is a 3 GeV synchrotron radiation laboratory in the detailed design stage. The main building site is being excavated in Qazvin, 150 km from Tehran. The Booster ring of this facility with a circumference of 504 m and a low emittance of 3.5 nm rad accelerates electrons from 150 MeV to 3 GeV. Using POISSON and OPERA codes, we designed the ILSF booster ring magnets including dipoles, quadrupoles, sextupoles, and separate correctors. Cooling and electrical calculations are done, and ramping effects are considered. The ILSF has also been attempting to practice mechanical designs and to build prototype magnets at this stage too.

Waste materials continue to increase and have become a major problem in many countries. In this work,waste was recycled to form bioplastic composites. The study focused on the bioplastic (starch-cellulose acetate)-carbon material composites. The Graphene Oxide (GO) and Carbon-dots (CD) were chosen as filler materials. The physical properties of these bioplastics were investigated using tensile test, water uptake test and biodegradation test. Results showed that the addition of GO and CD reduced the tensile strength and elongation. It was also found that the water uptake decreased while the biodegradation rate increased with GO or CD addition. The interaction between the bioplastic starch-cellulose acetate matrix and the carbon materials as fillers can change the mechanical properties of the bioplastics. The carbon materials fill in the pores in bioplastics and make the bioplastic more waterproof and their hydrophilic properties attract water faster and help the activation of microbial activity during the biodegradation.

Electron grid therapy is expected to be a valid treatment for bulky superficial tumors. It is difficult, however, to fit irradiation fields to bulky superficial tumor shapes for conventional electron grid therapy with a cerrobend grid collimator. In this study, we investigated whether a grid collimator using tungsten functional paper (TFP), with its radiation shielding ability, could be used for electron grid therapy. Dose distributions were measured using 9 MeV electron grid beams from a cerrobend grid collimator. For the simulation study, the same grid irradiation fields were shaped using a TFP grid collimator (thicknesses of 0.15, 0.3, 0.6, 0.9, and 1.2 cm) by laying them on a phantom. We then determined the dose distributions using Monte Carlo calculations and compared the cerrobend and TFP electron grid beams regarding dose distributions, including the depths of the maximum dose (d max), 90% dose (d 90), and 80% dose (d 80), and the ratios of the doses in the areas with and without shielding (valley to peak ratios). The equivalent dosimetric thickness was obtained with the TFP grid collimator that was equivalent to the dose distribution of the cerrobend grid collimator. For the cerrobend electron grid beams, the d max, d 90, and d 80 were 1.0, 2.1, and 2.5 cm, respectively, and the valley to peak ratios at those depths were 0.48, 0.66, and 0.73, respectively. The equivalent dosimetric thickness of TFP was 0.52 cm. The d max, d 90, and d 80 for the 0.52 cm thick TFP electron grid beams were 1.1, 1.9, and 2.3 cm, respectively, and the valley to peak ratios at those depths were 0.49, 0.63, and 0.71, respectively. The TFP grid collimator flexibly delivered excellent dose distributions by simply attaching it to the patient's skin. It could thus be used for electron grid therapy instead of the cerrobend grid collimator.

Nanofibrillated cellulose (NFC) is deemed to be environmentally friendly, green and inexhaustible material. Herein, Nanofibrillated cellulose (NFC) large length-diameter ratio were prepared by enzymatic pretreatment and mechanical method, and it was added into pulp as reinforcing agent to improve the performance of paper. The retention and loss efficiency of NFC in the paper preparation process were studied, and the retention and loss efficiency were characterized by analyzing the mechanical properties of the paper. It was found that the retention and loss efficiency of NFC decreased with the increase of NFC content. The addition of retention system in papermaking process has a positive effect on the retention efficiency of NFC. NFC can be uniformly distributed in the paper up to 8% with low addition. In addition, retention system can improve the mechanical properties of paper with high NFC content. Compared with the base paper, tensile strength, roughness, stiffness and air permeability of the paper increased by 111.38%, 100.95%, 152.63% and 96.80% respectively.

Sodium hyaluronate (HA) stabilized curcumin-Ag (Cur-Ag) hybrid nanoparticles were prepared in the water–ethanol mixture under constant mechanical stirring condition. The obtained HA stabilized Cur-Ag hybrid nanoparticles were characterized by fourier transform infrared spectroscopy, UV–visible spectroscopy, and x-ray diffraction to confirm the formation and structural interactions. The obtained Cur-Ag hybrid nanoparticles showed spherical shape with their size range 5–12 nm that was increased with the increasing a amount of silver ions as confirmed by transmission electron microscopic analysis. Further, a fibrous cellulose filter paper was impregnated with these hybrid nanoparticles and chitosan (CS) as biopolymer via polyelectrolyte complexation. The morphological analysis confirmed the uniform distribution of hybrid nanoparticle system onto the cellulose fibers of the fibrous filter paper. As per disc diffusion method, the Cur-Ag hybrid nanoparticles impregnated CS-coated filter paper exhibited excellent antibacterial properties against gram-negative Escherichia coli (E.coli) bacteria compared to HA stabilized Cur only. Moreover, as prepared hybrid nanoparticles impregnated biocomposite system is eco-friendly with efficient antibacterial property and have good potential to be used in medical applications.

With the application of battery becoming more and more widely in our life, the importance of battery production with high quality has been increasingly emphasized. Battery separator is one of the important factors that affect the performance of the battery, so the high functions separator production is particularly important. This article preliminary investigates the effect of pulp types, composition and beating degree on the performances of separator. Main research work:Beating softwood pulp, hardwood pulp and dissolving pulp for different degree by PFI, and papermaking, then detecting the physical properties of paper sheets. Through comprehensive analysis conclude that softwood pulp, hardwood pulp and dissolving pulp have excellent physical properties in the 40° SR, and thermal stability up to 200° in the process of heat treatment. The paper sheets are made using different ratio of softwood pulp, hardwood pulp and dissolving pulp, then test the physical properties. According to the comprehensive analysis of experimental datum obtained that the sheets made using mixed pulp (40° SR dissolving pulp: 40° SR softwood =5:5) have excellent physical performance, and sheet strength index decreased slightly at 200°C, compared to other ratios.

The objective of this study is to investigate the crushing strength of Kraft paper honeycomb with different thickness of cell wall and different cell size subjected to compression loading. At first, experimental tests were carried out on Kraft paper honeycomb with 10mm cell size and 0.6mm thickness of paper with different mass density (RO). Then, a finite element model was developed in order to study the effect of cell size and thickness of cell wall on crushing properties of Kraft paper honeycomb. Based on the simulation results, the cell size and thickness of cell wall of Kraft paper honeycomb influence the crushing properties of the honeycomb. Crushing strength increases with decreasing the cell size which for the range of the study, cell size 10mm shows the highest strength. Meanwhile, 0.4mm thickness of cell wall results the higher crushing strength of honeycomb. Also, higher density gives higher crushing strength where in this study is found for 2.236× 106 kg/mm3.

This paper presents the study of breakdown characteristic of Kraft paper insulated with two different types of insulating fluid, which are Palm oil and Coconut oil. Palm oil and Coconut oil are chosen as the alternative fluid to the transformer oil because it has high potential and environmentally-friendly. The Segezha Kraft papers with various thicknesses (65.5 gsm, 75 gsm, 85gsm, 90 gsm) have been used in this research. High Voltage Direct Current (HVDC), High Voltage Alternating Current (HVAC) and carbon track and severity analysis is conducted to observe the sample of aging Kraft paper. These samples have been immersed using Palm oil and Coconut oil up to 90 days to observe the absorption rate. All samples started to reach saturation level at 70 days of immersion. HVDC and HVAC breakdown experiments have been done after the samples had reached the saturation level based on normal condition, immersed in Palm oil and immersed in Coconut oil. All samples immersed in liquid show different breakdown voltage reading compared to normal condition. The analysis of carbon track and severity on surface has been done using Analytical Scanning Electron Microscope (SEM) Analysis. The results of the experiment show that the sample of Kraft paper immersed in Palm oil was better than Coconut oil immersed sample. Therefore the sample condition was the main factor that determines the value of breakdown voltage test. Introduction

A preliminary test was conducted to investigate the characteristics of linerboard and corrugated medium paper made from durian rind waste. Naturally dried durian rinds were pulped according to Soda-Anthraquinone (Soda-AQ) pulping process with a condition of 20% active alkali, 0.1% AQ, 7:1 liquor to material ratio, 120 minutes cooking time and 170°C cooking temperature. The linerboard and corrugated medium paper with a basis weight of 120 gsm were prepared and evaluated according to Malaysian International Organization for Standardization (MS ISO) and Technical Association of the Pulp and Paper Industry (TAPPI). The results indicate that the characteristics of durian rind linerboard are comparable with other wood or non-wood based paper and current commercial paper. However, low CMT value for corrugated medium and water absorptiveness quality for linerboard could be improved in future. Based on the bulk density (0.672 g/cm3), burst index (3.12 kPa.m2/g) and RCT (2.00 N.m2/g), the durian rind has shown a good potential and suitable as an alternative raw material source for linerboard industry.

A porous carbon prepared from waste palm kernel shells has been applied as a new supercapacitor electrode material. Activated carbon was synthesized through a carbonization process at a temperature of 400 °C which has a particle size of 90 urn and provide a surface area of 301.482 m2g-1. Carbon from waste palm kernel shells was distributed on a sheet of carbon paper surface with a variation of carbon paper and palm kernel shells carbon mass ratio. From the results reported that the capacitance value was increased to 1331.8 uF in rolling method with addition of carbon palm shells mass have higher capacitance values than which was obtained in plate or sandwich method.

We report the preparation, reduction and characterization of GO paper that obtained by assembly of individual GO sheets. The free standing GO paper was prepared from 4 mg/ml GO dispersed in water, and following by evaporation of water and then detach from the petri dish. In order to obtained graphene-like film, the free-standing GO film then thermally reduced by heating the samples at 250°C at varied heating time. Characteristic and properties of the thermally reduced GO paper was measured by means of infrared spectroscopy, X-ray diffraction and EDS.

A cost effective and easy to fabricate stress sensor based on pseudo-Hall effect in Graphite on Paper (GOP) has been presented in this article. The four terminal devices were developed by pencil drawing with hand on to the paper substrate. The stress was applied to the paper containing four terminal devices with the input current applied at two terminals and the offset voltage observed at other two terminals called pseudo-Hall effect. The GOP stress sensor showed significant response to the applied stress which was smooth and linear. These results showed that the pseudo-Hall effect in GOP based four terminal devices can be used for cost effective, flexible and easy to make stress, strain or force sensors.

Femtosecond laser ablation of freestanding reduced graphene oxide (rGO) paper and its mechanisms were investigated. An abnormal phenomenon was discovered: the ablated area remained unchanged for the rGO paper with an increasing number of pulses, which was found to be a general feature for a large range of laser fluences. We also studied femtosecond laser ablation of graphene oxide paper and highly oriented pyrolytic graphite film for comparison. Experimental results indicated that the abnormal phenomenon was unique to the rGO paper. As revealed by a combination of SEM, TEM, XRD and Raman techniques, femtosecond laser nonthermal ablation through rolling up of rGO nanoflakes, induced by the distinctive multi-level layer-by-layer structures and the ultrafast energy relaxation of the rGO paper, were considered to be responsible for the non-incubation effect.

Empty fruit bunches of oil palm is a by-product of the palm oil industry that contains a high element of carbon. This by-product can be processed into a conductive carbon paper that could be applied as fuel cell electrodes. Carbon paper for this application must be conductive, porous, and hydrophobic. Utilization of oil palm empty fruit bunches begins with the carbonization process at a temperature of 500°C that produced charcoal. It is followed by heating at temperature of 900°C and 1300°C. To obtain the carbon paper, powdered charcoal with polymer binder (PEG and EVA) were mixed in solvent and molded using tape casting method. This process successfully produced carbon paper with dimensions of ±(20x20) cm2 and a thickness of 0.1-0.3 mm. Properties of carbon paper were characterized and analyzed in terms of electrical conductivity, porosity, hydrophobic property, and microstructure. Polytetrafluoroethylene (PTFE), a hydrophobic agent, was treated on carbon paper to enhance the hydrophobicity of the carbon paper. PTFE coating on the surface of the carbon paper could change their physical properties. Carbon paper shows excellent properties in terms of porosity and hydrophobicity. Whereas, its electrical property needs to be improved further by increasing the pyrolysis temperature. But overall, this might show a potential GDL material for PEMFC.

In this work, we evaluated the feasibility of a paper-based bacterial detection system. The paper served as a substrate for the measurement electrodes and the culture medium. Using a printing technique, we patterned gold electrodes onto the paper substrate and applied Luria broth (LB) agar gel as a culture medium on top of the electrodes. As the first step towards the development of a bacterial detection system, we determined changes in the surface potential during bacterial growth and monitored these changes over 24 h. This allowed us to correlate changes in the surface potential with the different growth phases of the bacteria.

In this study, a paper-gate transistor was developed to detect glucose using an extended-gate field-effect transistor (FET). A filter paper was used as an extended gate electrode, in which Au nanoparticles (AuNPs) modified with phenylboronic acids (PBAs) were included. PBA–AuNPs play an important role as a support to not only be entrapped in cellulose fibrils but also bind to the targeted glucose in a paper. The surface properties of PBA–AuNPs were investigated to elucidate the electrical properties of the paper-gate electrode using an absorption spectrum and a zeta potential analysis. Moreover, the paper-gate electrode enabled us to detect glucose at the micromolar level on the basis of the principle of FET devices. A platform based on the paper-gate transistor is suitable for a highly sensitive system to detect glucose in trace samples such as tears, sweat, and saliva in the future.

Two carbon fibers were first fabricated by one-step pyrolysis of papers (filter paper and facial tissue), and then employed as catalytic materials for counter electrodes in dye-sensitized solar cells (DSCs) to investigate their potential application. The results show that the microstructure transformation and main weight loss of both the papers are mainly happened in the temperature range of 300–400 °C. After pyrolysis at 800°C, the weight remaining of the filter paper and facial tissue is 1.92% and 4.95%, respectively. The obtained carbon fibers belong to an amorphous carbon consisting of the randomly oriented stacks of graphene sheets. The diameters of both the carbon fibers are about 10 μm, on which there are a certain amount of fine carbon nanofibers. The amorphous microstructure and unique fine nanofibers of the carbon fibers induce more excellent catalytic activity for triiodide ion reduction compared with the biochar (derived from poplar leaf) and the graphite. As a result, the carbon fiber based DSCs display obviously higher efficiency than the biochar or graphite based ones. The conversion efficiency of the DSCs employing the filter paper derived carbon fiber, facial tissue derived carbon fiber, biochar and graphite is 4.72%, 4.70%, 1.33% and 0.77%, respectively.

A novel display mode called the mobile fine particle display (MFPD) is proposed. Fine particles doped and dispersed in nematic liquid crystals are used in our MFPD cell. The distribution of fine particles on a plane parallel to the substrate surface can be controlled by changing applied electric field, which is a DC field or an AC field adjusted by applying DC, to obtain optical changes in the MFPD cell. The velocity of fine particles is dependent on the electric force, dielectric force and friction force acting on the particles, and the flow of liquid crystals. The MFPD shows excellent characteristics such as a high reflectivity (approximately 50%), a high contrast ratio (more than 10), and a wide viewing angle. In addition, images displayed on the MFPD can be rewritten by the application of an electric field and be sustained under a no-voltage-application condition for a long time (over 5–7 months). The characteristics of the MFPD indicate that this new type of display is suitable for electronic paper displays.

We have carried out photoacoustic measurements of the thermal diffusivity on samples of laboratory produced chemically bleached wood pulps, as well as on samples of several commercially available papers. Our results for bleached pulps indicate that the thermal diffusivity is correlated to each of the chemical bleaching controlling parameters (the kappa number, viscosity and brightness) measured during distinct phases of the bleaching processes. Also, the values of the thermal diffusivities for the commercial papers were found to be adequate for their end uses. It turned out that photoacoustic measurements can be a valuable research laboratory and/or industrial plant tool for comparing and controlling the properties of pulp and paper and for evaluating the effects of processing parameters upon these properties.

Understanding of wetting processes for papers of various qualities is important for the analysis and the adjustment of paper-production processes as well as for designing properties of paper for printing. In this investigation, papers of one kind with three different sizing-content values were examined by time-dependent attenuation of ultrasound transmission in mixtures of isopropanol and water. The attenuation depends on the stage of absorption of liquid into the paper sample, which furnishes the signature of the paper type and quality. Papers that have contact angles of 40° (without size), 70° (low size content) and 110° (high size content) were tested and a measurement procedure was developed. The measurement results showed that the development of attenuation with time differs at different frequencies, indicating the possibility of detecting various phases of wetting phenomena.

A mesoporous NiO@graphite paper with multilayered nanosheet wall structures (M- NiO@GP) was synthesized through a facile and low-cost hydrothermal reaction and thermal annealing process. The as-prepared M-NiO@GP electrode presents high specific capacitance (2.57 F cm−2), exhibits superior cyclic stability (92.3% capacitance retention after 10000 chargedischarge cycles) and brilliant rate capability (about 56.0% capacitance retention when the current density increased 20 times). Such high-performance capacitive behavior is attributed to the wall structure of NiO with the multilayer nanosheets, which could shorten the ion transfer distance. Meanwhile, the high specific surface area and mesoporous structure of the electrode could serve as an efficient path for OH− transfer and diffusion. The improved electrical conductivity of the electrode enabled stable and efficient electron transports and consequently improved the overall electrochemical performance of supercapacitors. Therefore, the demonstrated high conductive M-NiO@GP electrode is a promising candidate for practical supercapacitor applications.

Electrostatic discharge, as a common natural phenomenon in daily life, seriously threatens the reliability of integrated circuit products. In order to ensure the yield of the chip, the protection circuit on the chip has become an essential and important module in the circuit design. With the continuous development of integrated circuit technology, chips are developing towards the direction of smaller area, faster speed and higher level of integration, while traditional devices such as simple diodes, tubes and SCR on integrated circuit can no longer complete the protection task of chips under advanced technology. Through the research and discussion of this paper, the methods and strategies of electrostatic discharge protection design of integrated circuits and how to choose the best electrostatic discharge protection scheme for different integrated circuits are basically mastered.

Indonesia is the largest contributor to marine plastic waste in the world after China. One solution to reduce plastic use is to develop a packaging that can be degraded by nature and eco-friendly, called bio-packaging. In this paper, we create bio-packaging made from a composite of waste paper and coconut fiber. In addition to composites’ physical characteristics such as mechanical properties and its biodegradability, this research also measured community responses to the bio-packaging products. This bio-plastic can be applied to making packaging with a lifting strength of more than 10 N. Also, it can be degraded into freshwater and seawater. According to the perceptional test, the bio-packaging is superior to single-use plastic except in the strength aspects.

In this study, an efficient fabrication method to realize a reversible thermo-responsive composite (TRC) and the effect of raster angle were investigated. For the facile fabrication of reversible TRCs, polylactic acid and commercial printing paper were used to generate a polymer/paper bilayer. Using the fused deposition modeling method of three-dimensional printing, three types of TRCs were fabricated and compared depending on the printing angle condition. Above the glass transition temperature, the polymer is relaxed, allowing straightening by the constraining paper layer; subsequently, it recovers its initial shape during cooling. Because the deposited filament arrays shrank in the longitudinal direction and expanded in another direction during heating, the raster angle was considered for better actuating performance. Thus, horizontal-type TRCs exhibited a greater range of average actuating performance compared with vertical-type TRCs (up to ∼24.7% increase in changing rate). Hence, this study supports a rapid, low-cost, and efficient fabrication method for soft robotics applications, including smart devices, grippers, and actuators.

This paper describes the effect of preceramic paper composition on microstructure and mechanical properties of Ti3SiC2-based composites. The preceramic paper with Ti3SiC2-powder filler and different content (from 10 to 40 wt.%) of organic component (cellulose) was prepared. The composites were obtained by spark plasma sintering (SPS) at 50 MPa pressure for 10 min holding time. The sintering temperature was 1473 K. The influence of organic content on microstructure, phase composition, and flexural strength of the sintered materials was analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and mechanical testing, respectively. It was revealed that the microstructure of the sintered materials became more porous with increasing of cellulose content in the paper. XRD analysis showed the presence of Ti3SiC2, TiC and TiSi2 phases in the sintered samples while the content of the Ti3SiC2 phase increase with decreasing of the organic content. The flexural strength changes from 100 (40 wt.%) to 300 MPa (10 wt.% organic binder) that is caused by porosity of the composites.

Partial discharge along the surface seriously damages the oil-paper insulation performance and ultimately leads to insulation failure, which greatly reduces the safety and reliability of the converter transformer operation. It is important to understand the failure process of oil-paper insulation under partial discharge along the surface to avoid fault occurrence. In this paper, the failure process of oil-paper insulation under partial discharge of pulsating DC and AC voltage is studied. A partial discharge test platform for oil-paper insulation under pulsating DC voltage was built. The partial discharge test of oil-paper insulation along the extremely uneven electric field was simulated by using the needle plate and column plate discharge model. The oilpaper insulation under two kinds of voltages under the extremely uneven electric field was analyzed in depth. The similarities and differences of the failure process and their causes, the insulation design and operation and maintenance recommendations for preventing flashover under the extremely uneven electric field are proposed.

In this research, paper-based SERS active substrates with different grade gram per square meter (GSM) were prepared by adsorbing 40 nm spherical GNP and 40nm star shaped gold nanostructures GNS. Besides the SERS evaluation and optimization, morphological parameters of the samples were found to strongly affect the enhancer properties of the substrates. The developed substrate was tested regarding surface homogeneity as well as by the Raman reporter dye Methylene Blue (MB). These paper-based SERS active substrates are simple to prepare, easy to handle and cheap solid SERS substrates. GNS with 135 GSM printing paper can be easily used as highly active SERS active substrates, with average enhancement factor EF= 105.

In the current period, many transformers in domestic power supply departments are in the state of overdue service, there are many problems of insulation aging and increasing water in the body, and the rapid and accurate insulation moisture assessment is a technical problem that needs to be solved. The commonly used methods of medium response test for damp evaluation of transformer oil-paper insulation system include time-domain PDC and frequency-domain FDS. These two methods have their own advantages, but also have their own disadvantages. The purpose of this paper is to transform these two test methods into time-frequency combined medium response technology combining time-domain PDC method and frequency-domain FDS method, which can be used in transformer oil paper insulation moisture evaluation to improve the efficiency of transformer operation detection. In this paper, PDC method, FDS method and time-frequency combination method were used to obtain the response curves of insulating oils with different water contents, and the curves were analyzed. By comparing the results of measuring time and water content, the effectiveness of time-frequency combination method was verified. The experimental results of this paper further show that the time-frequency domain combined media response technology has a good application value in the evaluation of transformer oil paper insulation damp.

Concrete structure deterioration and design deficiencies are stated as serious problems that frequently occur in the construction industry. It may lead to the loss of strength, stiffness, durability, and ductility of the existing structure. Therefore, an immediate structural strengthening must be highly considered to improve and repair the structure performance due to which the structure may fail to serve its purpose. The aim of this paper is to provide review of the structure strengthening methods for reinforced concrete columns proposed by researchers in the past two decades. However, the scope of this review paper is limited only to reinforced concrete columns retrofit by using the material of shape memory alloy (SMA). At the end of this paper, a suitable SMA form will be proposed for the future direction of research into this strengthening method.

The effects of three factors, such as aging degree, water content and temperature, on the dielectric response characteristics of oil-paper insulating materials were studied by setting up a frequency-domain dielectric response experimental platform. In this paper, the frequency domain dielectric spectrum (FDS) test is carried out for the on-site transformer paper insulated casing, and it is found that the method is more abundant than the traditional power frequency dielectric loss method, which is less affected by the work frequency electromagnetic field, and can realize the nondestructive measurement of the aging state of the oil-grease insulation.

Mixed oil is considered as an ideal insulating fluid for its great physicochemical and insulation properties. A novel mixed oil consisted of 75 vol.% mineral oil and 25 vol.% palm oil, was developed by our team and its main properties basically come up the standards of IEC 60296:2012. In this study, the dielectric properties of mineral oil-impregnated paper (MIN-IP) and mixed oil-impregnated paper (MIX-IP), were comparative analyzed at 25 °C-65 °C, including relative permittivity and dielectric loss factor. The temperature effect on AC breakdown properties for MIN-IP and MIX-IP were also researched at 25 °C-75 °C. The result shows that MIX-IP have higher relative permittivity and dielectric loss factor than MIN-IP. The difference on dielectric strength between MIN-IP and MIX-IP is more significant at 45 °C to 65 °C.

Silica element can be used as one of additional elements in a material. It is good to improve the thermal properties so it can stabilize the heat resistance of a material. The silica gel resulted from the extraction process of rice husk ash can also do the stabilization of heat resistance. This element is known to be able to reduce the fire rate in a material. In this research, the fire rate on a paper is analyzed from the result of paper coating by using the silica resulted from the extraction of rice husk ash. It is done by using the flammability test device. The silica gel used to coat the paper is obtained from variety of time during the extraction process, so it will give a difference toward the fire rate on the paper. From the research result, the paper coated by the silica gel sourced from the extraction of rice husk ash with the shortest amount of heating time has the lowest fire rate compared to other samples. It means that the percentage of silica gel obtained from the extraction of rice hush ask with various time variety is in line with the reduction of fire rate.

A platinum-coated singlemode-multimode structure is investigated in this paper as an optical fibre sensor (OFS) to monitor the phase transition of a phase change material (PCM). Paraffin wax has been used as an example to demonstrate the sensor's performance and operation. Most materials have the same temperature but different thermal energy levels during the phase change process, therefore, sole dependency on temperature measurement may lead to an incorrect estimation of the stored energy in PCM. The output spectrum of the reflected light from the OFS is very sensitive to the bend introduced by the PCM where both liquid and solid states exist during the phase transition. The measurement of strain experienced by the OFS during the phase change of the PCM is utilized for identifying the phase transition of paraffin wax between the solid and liquid states. The experimental results presented in this paper show that the OFS can measure the phase change point of paraffin wax and the sensor with a multimode fibre length of 10 mm measured the phase transition temperature range from 37.8 °C to 57.7 °C.

The wide application of anaerobic digestion (AD) for waste sludge results in a huge amount of digested sludge, while the appropriate reuse of digested sludge depends on effective solid-liquid separation. Thus, chemical (acid/alkali) pretreatment effects on dewaterability of digested paper mill sludge (DPMS) for better downstream reuse based on enhanced solid- liquid separation were investigated in this research. The dewatering properties of paper mill sludge (PMS) were also investigated to elucidate the impact of AD on sludge dewaterability. The results indicated that a higher DPMS dewaterability was noted with acid pretreatment (pH5). A 41.37% moisture content and 74.41% dewatering efficiency were determined for DPMS after acid (pH5) pretreatment within 25 min. In addition, a 7.13 mg•g-1 VSS of extracellular polymeric substances (EPS) and 101.50 μm of average particle size were observed. It was also observed that both EPS concentrations and particle sizes were key parameters influencing DPMS dewaterability. Lower EPS concentrations with larger average particle sizes contributed to enhanced sludge dewaterability. Moreover, dewaterability of PMS was higher than that of DPMS, which illustrated that AD would decrease the sludge dewaterability.

In modern years, effective utilization of high performance concrete in construction because of their increase in durability and mechanical properties. In particular high performance concrete is made by replacing/introducing mineral admixtures and chemical admixtures with cement or replacing/introducing the fibers into the concrete. The focus of this review is to illustrate the properties of the various materials used, mix proportion of materials to make high performance concrete and observation of high performance concrete. Moreover there are three main groups which are important in manufacture of high performance concrete they are increase of workability, increase of strength and increase of durability. Finally the studies on the high performance concrete have been reviewed.

This review is aimed at exploring the possibilities of recovering Chromium ions using several low-cost adsorbents through wastewater processing. In the past, several traditional methods were employed for removing Chromium ions. These included precipitation, evaporation, electroplating and ion exchange. However, these processes were associated with various limitations, which included the treatments to be restricted to a certain concentration of the Chromium ions. Therefore, the process of using low-cost adsorbents can be deemed as an eco-friendly one. At the moment, an enormous amount of natural materials and agricultural waste are produced, which extremely harmful to the environment. Thus, adsorption is an alternate process for removing Chromium ions. Based on the enhanced characteristics of the process of adsorption, such as cost-effectiveness, improved adsorptive properties, and increased availability, the process is definitely an economical one for removing Chromium ions. This review provides a brief appraisal of the relevant literature which exists on the low-cost adsorption for removing Chromium from polluted wastewaters. Additionally, in order to comprehend the overall adsorption process of low-cost adsorbents, this review will also explore the various existing adsorption models. These include the isotherm, kinetics, and thermodynamics along with the impact of various factors on the process of adsorption.

Flame flashback phenomena and combustion stability in a swirl burners represent the major of instability problems that lead to causing a considerable damage to combustion systems as well as the pollution troubles. Recently, researchers suggested many techniques in order to enhancing flame flashback resistance especially against a combustion induced vortex breakdown mechanism in addition to boundary layer flashback. Therefore, the present paper represent a general review about flashback and combustion stability in swirl burners to be as a scientific reference for researchers in this field.