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Langmuir-Blodgett technique was applied to build optically homogeneous film of functionalized multi-walled carbon nanotubes (MWCNTs) on paper substrate. The palladium (Pd) nanoparticles were drop-casted onto MWCNTs network films before being exposed in hydrogen (H2) gas molecules environment under vacuum and atmospheric pressure at room temperature. The results demonstrate that the functionalized MWCNTs dispersed with Pd nanoparticles show good H2sensing response on paper substrate where the sensitivity of around 10 % was recorded at only 2 minutes exposure time.

Magnetic stripe cards and magnetic recording paper are commonly used in credit cards, identity cards, and transportation tickets. Barium ferrite was used to prepare magnetic inks and the magnetic ink was coated onto the paper substrate to obtain the magnetic papers. The crystal structure of barium ferrite was characterized by X-ray diffraction (XRD) and the magnetic property of barium ferrite was tested by vibrating sample magnetometer (VSM) The performance of the magnetic recording paper and the surface morphology of the coating magnetic layer were also characterized. The results show that the magnetic ink based on barium ferrite with the formula of 41wt% of the barium ferrite powder, 14wt% of polyurethane, 36wt% of solvent and 9wt% of PVP has good printing characteristics and the magnetic recording papers have good performance.

The experiment studied effects of paper on the height and glossiness of UV ink-jet 3D printing. The results showed that there all existed penetrations between the 1st ink layer and three kinds of paper, the bigger the roughness and bulk of paper were, the larger the penetration was, and penetration between the 1st ink and paper was obviously larger than that between two ink layers. Penetration between two ink layers was stable, almost not affected by paper. The bigger the roughness and bulk of paper were, the smaller the glossiness of ink layer was. There appeared directional ink strips on ink layer on three kinds of paper, beginning from the 3rd ink layer, there also appeared ink pits on ink layer on paper whose roughness and bulk were the biggest, which showed printer precision was also an important factor for the glossiness, apart from paper. Thus, the tight and smooth paper should be selected in UV ink-jet 3D printing. Before printing, pretreatment should be done to exclude the influence of the 1st ink layer and the ink strips.

In this study, four types of Waste Paper Sludge Ash (WPSA) were explored for use as Supplementary Cementitious Materials (SCM) in binary system. The WPSA use varies in particle size range and surface area however similar in chemical composition. At first stage, Ordinary Portland Cement (OPC) was replaced by WPSA at 5% mass to mass basis as blended cement. Four size of WPSA was prepared which are unsieve, retained at 63μm, retained at 45μm and pan. WPSA blended cement (WPSABC) was introduced from the four size of WPSA that prepared earlier. Water to cement ratio selected was 0.50 and it keep constant at all type of blended cement. When compared with the control mix, result shows that hydration kinetics is affected by the particle size of WPSA. Pan WPSA has slightly higher peak of hydration kinetics and compressive strength of blended cement. At second stage, Pan WPSA was selected to undergo the further investigation on its performance. Pan WPSABC were prepared at replacement level of 5%, 10%, 15% and 20%, mass to mass basis. Same method and w/c ratio was used and compared with control mix. From the result, it is found that the peak for rate of heat evolution of Pan WPSABC occur earlier and slightly lower as compared to OPC. Pan WPSA also achieved it optimum strength at 5% replacement level which is more than control mix.

There are many researches about the effect of oil/paper proportion, testing temperature, AC/DC ratio and other effects on the breakdown characteristics of oil-paper insulation under the composite electric field. However, the breakdown characteristics of oil-paper insulation under the composite electric field in the process of ageing are rarely reported. In this paper, the breakdown characteristics of the oil impregnated insulation paper with different ageing condition under the composite electric field were investigated. Results show that there is no necessary link between the breakdown characteristics and the ageing degree of oil-paper insulation. The breakdown voltage value decreased with the rise of the AC component under the composite electric field. The breakdown voltage with aged paper changed by new paper is slightly higher than that of the aged oil being changed by new oil.

As a non-destructive insulation diagnostic technique, the polarization spectrum method based on return voltage measurement has been employed to assess the state of insulation of the transformer. But how does the moisture content affect the parameters of RVM is not clear. In this paper, the effect of moisture content on the parameters of return voltage is studied based on experiments. The result shows that maximum value of return voltage (Urmax) and initial slope (Si) increase with the increase of moisture content in second-order function, while the central time constant (tcdom) decreases with the increase of moisture content in second-order function. The central time constant varies strongly with the change of moisture constant, so it is considered as a reliable indicator to evaluate the moisture level in oil-paper insulation system of transformer.

Silica of hollow structure exhibits a number of special characteristic. In this paper, a new way to prepare hollow silica spheres which can be used as filler for paper was reported. In this approach, when silica shells were coated on polyvinylacetate (PVAc) template particles by the sol-gel method, the PVAc cores would be dissolved synchronously, forming hollow spheres. Neither additional dissolution nor a calcination process was needed to remove the PVAc cores. The morphology of the hollow silica spheres was also characterized by TEM. It was shown that the hollow silica spheres with 130-400nm in diameter and 15-35nm in the shell thickness could be synthesized. The possible formation mechanism was also brought forward. The possibility and potential advantages in usage as filler for paper were analyzed theoretically. We confer that this filler can improve the printability of the paper, and reduce its density compared with traditional fillers.

The light inspection on surface finishing of most product measurement is an important feature in the industries. In this study, a lab module tester for examination on the different type quality of tissue paper quality was done. The light reflectance element was used in this study to differentiate the quality of tissue paper. The laser diode and photodiode was used as manipulator to differentiate the tissue paper and photo detector to detect the reflected light from the surface of tissue paper. The both of laser diode and photodiode were placed in a light box. Different level of intensity reflected from the surface material will have different voltage output. The result showed that the total ply high quality tissue paper has a higher reflected voltage output compared to low quality tissue paper.

Binder is the essential component of coating color recipe. The amount and type of latex binder has a significant effect on both the structure and chemical-physical properties of coated paper, which affect critical surface properties, e.g., print gloss, roughness, ink setting rate via liquid absorption, and print mottle The main aim of this study was to investigate the effect of coating solid on the binder distribution in the method of numerical analysis by Laser Scanning Confocal Microscope (LSCM). In this study, Rhodamine B was used to stain the binder and as the probe to characterize z-directional distribution of the binder using LSCM. The results implied that it was reliable and effective method using LSCM to characterize the z-directional distribution of binder and analyze the influence of coating solid on binder distribution in the z-direction. It could be concluded that the coating solid played an important effect on binder distribution in coated paper and low coating solid with more water accelerated binder migration to the interior of base paper, sample with 60% coating solid is good to binder distribution and coating layer forming.

The effects of aluminum foil packaging materials on color reproduction were mainly studied from the following two aspects in this topic: (1) through the study of CIEl976 chroma space, color difference evaluations of 7 kinds of colors for aluminum foil were compared with that of coated paper, based on the established color libraries of coated paper. (2) Four different spectrophotometers of X-Rite were used to measure L*、 a*、 b* of different colors, analyzing the effects of different spectrophotometer on color reproduction. Research has proved that: (1) the method which color was transferred to the aluminum foil, according to the established color libraries of coated paper, is feasible, and there was no difference between two colors on aluminum foils by visual inspection, the chromatic aberration was less than 1. (2) From the measurements, aspheric photometers like X-Rite939, Spectroeye, X-Rite500 cannot be used for color measurement on aluminum foil, the error is bigger than SP64, and accuracy is lower. (3) Through the total color difference analysis of four instruments on magenta, the ball SP64 portable spectrophotometer is the most suitable equipment for color reproduction on aluminum foil packaging materials.

The size and the number of folds severely affect the performance of the diesel fuel filter. Computational fluid dynamics method was applied to diesel filter internal flow simulation, and flow pressure lost was test to verify the simulation result. CFD result shown that, when the filter paper angle less than 3°, the internal flow resistance of fuel filter grown rapidly. The flow resistance decreased slowly when filter paper angle of greater than 6°. If filter paper angle was less than 3 °, effective filter area of filter decreased sharply, and filtration efficiency was lower than limit. The filter paper dust capacity increased rapidly, when filter paper angle was greater than 4.5 °, which prolonged filter life. In order to ensure the flow resistance, filtration efficiency and service life, the angle of the filter paper should be between 3 ° to 4.5 °.

Graphene is a material that has been heavily investigated in many researches due to its beneficial characteristics such as large surface area, low manufacturing cost, high electro conductivity and incredible mechanical strength. Applying the graphene in water-based solvents however can cause agglomeration due to its hydrophobic properties. Researchers have composited the graphene with other materials in overcoming its hydrophobicity. In this research, graphene was nanocomposited with thionine to make it disperse well in water-based solvents while preserving its intrinsic properties. The nanocomposition process involves mixing of both graphene oxide with thionine and were reduced by hydrazine hydrate while reflux heating. The produced mixture was then filtered to obtain the Thionine-Graphene nanocomposite. The obtained sample was then characterized to confirm the composition of both graphene and thionine. Fourier transfer infrared spectroscopy was operated to investigate the chemical bonds and hence concluding the presence of both graphene and thionine in the sample. The preservation of the intrinsic properties of graphene was also investigated through observing the absence of functionalized graphene bonds. Post-investigation reports that the chemical bonds from both of the materials, graphene and thionine were detected confirming the successfulness of the nanocomposition.

Renewable energy is rapidly gaining importance as an energy resource to help aid the national energy depletion crisis of fossil fuel and coal. One of the most potential renewable energy sources in Malaysia is hydropower followed by solar energy. This paper presents the fabrication of Dye Sensitized Solar Cell (DSSC) using organic dyes from dragon fruit and chlorophyll which is extracted from spinach. The fabrication of DSSC uses the Dr.blade method. Result shows that the efficiency by using dragon fruit as sensitizer at 40µm TiO2 Thickness is 6.45%, better than the usage of chlorophyll dye which is 4.23% at the same thickness. Result also shows that at 80µm by using the dyes from chlorophyll extract has higher solar cell efficiency compare to dragon fruit. This shows that both the chlorophyll extract and dragon fruit shows potential in the development of a feasible working organic dye.

Graphene-based composites now has been payed more and more attention to because it can make up many shortcomings of the pure single-layer graphene.In many papers ,there are one same phenomenon said that graphene can not be well dispersed in matrix since it’s high specific surface area and high surface energy.In this work,we reported the preparation of ZnO/graphene nanocomposites through the way of situ-reaction in the surface of graphite oxide.Then,the nanocomposites were characterized by X-ray diffraction (XRD), Fourier Transform-Infared spectroscopy (FTIR),transmission electron microscopy (TEM), and thermogravimetry (TG). The results indicated that the graphene oxide had been reduced by hydrazine hydrate and the ZnO crystal attached to the surface of graphene well.The ZnO/graphene nanocomposites can be expected to be dispersed in some kinds of rubber to improve their electric and thermal conductivities in the following experiments.

The preparation of poly crystalline graphene from the liquid phase has been discussed.The mechanism of graphene growth from the liquid phaseon the Cu-Ni alloy and the type of atmosphere, used inthe graphene fabrication-acetylene, ethylene, hydrogen has been presented. Stages of nucleation and poly crystalline growth of graphene were identified. The paper presents theresults of a single-and multi-layered graphene growth phase.It is assumed the final result will mean the optimization of the industrial-scale production of low-cost poly crystalline graphene.

Graphene sheets offer extraordinary thermal, electronic and mechanical properties which could enhance the performance of the device for various applications. However, a large quantity production and the direct dispersion of graphene or graphite sheets in water without the assistance of dispersing agent has been considered to be a challenging issue. In this study, we reported that by introducing the functional group on the graphene basal plane started from natural graphite can readily form stable graphene oxide (GO) solution in a large quantity through modified hummers method. Structural and physiochemical properties of the GO were investigated with help of Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR). The effects of the annealing treatment on a GO surface were analyzed using a Semiconductor Parameter Analyzer (SPA) in order to obtain the electrical resistance measurement. Based on the thermal reduction results, the resistance of drop casting is greater than spray coating which indicates that, the drop casting method is more reliable to be used in any application.

Palm Oil Fuel Ash (POFA) is one of the solid waste in Malaysia and had trouble with the ash removal. Therefore, the use of waste oil palm ash can overcome the problem of solid waste. POFA is a pozzolanic material and it can act as a replacement of cement (OPC) to produce concrete with higher strength and low cost. POFA quality will increase as the range made up to a medium level of fineness in the size of 50 microns. POFA used to replace OPC is 0%, 10%, 30% and 50% by weight percent of OPC. POFA concrete compressive strength will be tested after a curing process that concrete age of 7 days and 28 days. POFA concrete density is also tested and compared with OPC concrete. Results showed that compressive strength POFA lower than normal concrete. On the other hand, the replacement of cement by 10% POFA shows a record high in compressive strength compared with other POFA mixing at the age of 7 days and 28 days. Fineness pozzolanic POFA is the best material and can be used as a cement replacement alternative.

In this work biodiesel of various proportions has been blended with E20 (20% ethanol and 80% diesel). Bio-diesel concentrations are varied at 10%, 20% and 30% while ethanol concentration was maintained at 20%. Performance, emission and variation of ignition lag of the fuel blends were analyzed. There was a very good reduction in CO emissions by 28% in comparison with E20 and 80% in comparison with diesel. NOx emissions of the blends were decreased by 16% compared with diesel and no variation with E20. Brake Thermal Efficiency (bte) of the blends was higher by 11% up to 75% load and 4% at full load compared with diesel and lesser by 2% in comparison with E20. Ignition-delay of the blends was longer than diesel, and the cetane number of the blends were lower than diesel. Brake Specific Energy Consumption (bsec) is slightly higher than diesel.

Slurry Seal is an impermeable non-structural thin layer that is used for pavement maintenance consisting of a cold laid mixture of asphalt emulsion with continuous graded fine aggregate, mineral filler, water and other added ingredients. Ordinary Portland Cement (OPC) as the main filler in the application of slurry seal. Due to the relatively high cement prices and the pollution control for the environment; it is required to maintain the quality of the slurry by using a combination of OPC and LCFA (Low Calcium Fly Ash). This research was conducted to determine the value of consistency, setting time and indirect tensile strength (ITS) of slurry seal containing LCFA. A consistency testing used to obtain optimum moisture content to produce the sample for the rest of the test. The results show that with the addition of 5% water for pre-wetting and subsequently 10% of water content, the mixture provide appropriate consistency as required by highways standard. The time settings also meet the requirements of highways standard between 15 to 720 minutes for all types of mixtures. The mixture with composition of 50% OPC and 50% LCFA is considered as an ideal mixture at the optimum density value of 1.769 g/cm3, porosity of 9.55% and the indirect tensile strength of 30.99 kPa. It could be concluded that fly ash can be used as OPC partial replacement and enhance the properties on slurry seal application.

Cement-based solidification/stabilization (S/S) has been considered as an effective method to deal with hazardous wastes such as textile dyeing sludge. In this study, sludge from textile wastewater treatment plant was solidified by Portland cement and attapulgite at different mass ratios (sludge 0.1~0.8, cement 0.1~0.8, attapulgite 0.1~0.8), and the characteristics of the solidified blocks were evaluated. The maximum unconfined compressive strength (UCS) of 15.8 MPa was obtained at 28 d when the mass ratio of attapulgite, sludge and cement was 0.1:0.1:0.8, while in toxicity characteristic leaching procedure (TCLP) test, relatively low concentrations of COD (100~150mg/L) in the leachate were found when the mass ratio was set to 0.3:0.1:0.6. Results of XRD and SEM/EDS indicated the existence of calcium silicate hydrate (CSH) in the solidified blocks. ANOVA results proved that the quadratic model could be utilized to characterize the relationship between COD of the leachate and the components in the mixture.

This paper studies the performance change by adding a certain percentage of graphene and high-temperature reduction graphene to copper powder,which would be sinteringed by Spark Plasma Sintering (sps) under certain temperature and pressure. The image of electrical conductivity measured by Physical Property Measurement System (ppms) showed that the electrical conductivity of the sample added with graphene increased by 4.39% compared with the sample added with no graphene. Meanwhile ,hardness increased by 50%. It showed that graphene could improve the conductive properties as well as the strength of copper, which suggests the graphene will have great potential application in power transmission conductor and electrical contact materials.

The safety storage of rice or brown rice moisture content is below 14% ,hardness and brittleness is larger to low moisture content of brown rice, the crack in the manufacturing process of milling rice and broken rice rate is higher, milling processing energy consumption to increase, and the rice surface roughness is low .In this paper, using mathematical simulation method based on the theory of the humidifying, thin layer of humidifying dynamics model is established, and brown rice humidification conditioning properties are studied. Results show that the unit heat consumption is reduced with the increase of air temperature,humidifying rate increases, the bread machine temperature linearly increases; With the increase of wind speed, unit heat consumption increases, humidifying rate increased.

what the cheaper and easier to get is graphene to replace high cost, limited sources of material and high temperature difference between the ITO (indium tin oxide) electrode material as a quantum dot solar cells is the focus of this study. This study used a chemical vapor deposition (CVD) production of graphene electrode explore the relationship between the transmittance and the graphene sheet resistance graphene layers; then make a graphene material as an electrode of the solar cell devices of different size and detecting its performance, the conclusion that the material is graphene electrode PbSe / CdSe quantum dot battery, which can effectively improve the conversion rate of the quantum dot solar cells (up to 3.6%), and stability, but also can greatly reduce the cost

Graphene oxide is prepared by modified Hummers method with the expanded graphite prepared from large flake graphite as raw material. The large tracts of graphene sheets prepared by ascorbic acid chemical reduction of graphite oxide are characterized by scanning electron microscope and X-ray diffraction. The electrochemical performances of graphene sheets are studied successively. The results show that large tracts of graphene sheets as an anode for lithium-ion batteries exhibits a high capacity of 1693 mAh·g-1 after initial discharge at a current density of 100 mA·g-1 and remains 426 mAh·g-1 after 100 cycles. The graphene sheets show good cycling stability even at high current density. The reversible specific capacities remains 218 mAh g-1 at the current densities of 1000 mA g-1 after 100 cycles.

Porous graphene is a collection of graphene-related materials which exhibits properties distinct from those of graphene, and it has widespread potential applications in various fields. Several approaches have been developed to produce porous graphene. However, the large-scale production of porous graphene nanosheets still remains a great challenge. Moreover, the costs of some methods are prohibitive for its commercial production and the processes are too complicated and time-consuming. In this work, we propose a simple and green method by which graphene nanosheets can be etched by sodium hydroxide under autogenous pressure at 180 °C. The morphologies and surface elements of the porous graphene nanosheets and sizes of pores were characterized. It is demonstrated that the one-step etching of graphene nanosheets is an effective method to obtain large-scale porous graphene nanosheets with high and uniform porosity. The pores in the porous graphene nanosheets were 6 nm depth (the same as the thickness of the graphene nanosheets) and 30-50 nm width.

Porous graphene has been easily synthesized by hydrothermal treating reduced graphene oxide in alkaline solution, and the porous structure was confirmed by transmission electron microscope. When used as supercapacitor electrode, porous graphene holds a specific capacitance of 88 F g-1 at an ultra-high current density of 50 A g-1, an increase of about 83% compared with that for the pristine graphene sheets. The results demonstrate that porous graphene opens a new and short way for ion transportation. Furthermore our findings provide a novel strategy to fabricate porous graphene and the process is simple, low-cost and environmentally friendly.

The superparamagnetic graphene/Fe3O4nanocomposite has been successfully prepared via an easy and scalable chemical precipitation method. High quality graphene sheets were prepared from natural flake graphite by oxidation, rapid expansion and ultrasonic treatment. The structure of graphene and graphene/Fe3O4nanocomposite was investigated by transmission electron microscopy, Xray diffraction and Fourier transform infrared spectroscopy. The graphene sheets possess a curled morphology consisting of a thin wrinkled paper-like structure. The graphene/Fe3O4nanocomposite exhibits a superparamagnetic behavior, its specific saturation magnetization,Msis 38.92 emu g-1.

The graphene (GE) films were fabricated in this paper through the deposition of graphene oxide (GO) sheets onto the quartz slide by means of dip-coating technique, followed by thermal annealing. The growth process and transmittance of the film were monitored by ultraviolet and visible spectrophotometer (UV-Vis), the surface morphology and structure were investigated by Atomic force microscopy (AFM), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Raman. The sheet resistance of the film was also tested and results showed that the sheet resistance is about 60 kΩ-1and the transmittance is as high as 81 % (at 550 nm).

Graphenes have aroused great interest among the scientists lately, due to their special physical properties which are supposed to be transferred to composite materials [1,2,3,6]. Some polymers show low mechanical properties which can be improved by adding various types of materials [9,13]. Using nanoparticles, an enhancement of mechanical, thermal and electrical properties can be obtained, even for small contents of additives [10,11,12,14,15,16]. The evaluation of mechanical properties of polymer composites with graphene can be achieved relying on the three-point bending tests [4]. This work presents a few conclusions resulting from the three points bending tests of the polyester composites with graphene and graphite [7,8].

Graphene oxide (GO) thin films were fabricated into thin film sensor for the selective VOCs detection. Different concentrations of GO aqueous solutions (6.2g/L and 5.0 g/L) were tested and thermally treated to obtain the appropriate sensing layer in terms of specific surface area and functional group. For the selectivity, it was assumed that different numbers and types of attached functional group of GO could induce the difference in gas adsorption, which may consequently derive to the selective VOCs detection. FE-SEM, XRD, and FTIR were utilized to characterize crystalline phase and functional group change by heat treatment condition and resistance measurements were followed. We suggest that thermally treated GO thin film sensor can be the alternative approach to achieve the improved selectivity in multiple gas detection by controlling the degree of gas adsorption.

This work focussed on the optimisation of product yields from the pyrolysis of palm kernel shells (PKS). 479g of dried PKS were loaded into the retort and then placed inside the furnace chamber and this was pyrolysed at 300, 400, 500, 600 and 700°C. The pyrolysis products obtained are char, tar (pyro oil and pyroligneous acid) and gas. A full factorial design (FFD) consisting two factors (Temperature and duration of pyrolysis) at three level was used to study the pattern of product yields from the pyrolysis of PKS. Char, tar and gas were evaluated as the responses. Thirteen experimental runs resulted from the FFD with a minimum product yield of 0.9wt% and maximum product yield of 99wt%. Response surface methodology was used to analyse the results of the FFD of the product yields of PKS. The optimum conversion yields expressed as a percentage of oven-dried weight of palm kernel shells of char, tar and gas products at their respective pyrolysing temperatures were 99wt% char at 304°C, 35wt% tar at 700°C and 39% gas at 700°C. The duration for the pyrolysis process was 20mins for 479g of dried palm kernel shells. The results of the work show that palm kernel shells can be readily pyrolised to obtain optimum yield of gas, tar (mixture of pyrolitic oil and pyroligneous acid) and char.

The application of high voltage electric field for preservation of fruit juices has a promising scope in the food industry. The pulsed electric field (PEF) is an innovative non- thermal technique and free from bio-toxic effects. The technique has a viable solution of the problem yet faced in the food industry to prolong life and preserve and maintain quality with natural properties of the liquid food and beverages. In this study, we have treated the pineapples juice samples by different strengths of pulsed electric field such as 10, 20 and 30kV/cm for 5 minutes in each test. This study used new design of helix treatment chamber with three different lengths of 20, 30and 50cm. In these experiments, all samples were kept in same and normal condition with a temperature around 25-26 andthe humidity was between 55 and 65%. Then the observation based on chemical tests such as pH, conductivity, salinity and total dissolved solids (TDS) was recorded for all samples before and after the test. Based on results obtained by chemical parameters suggest that the injection on pulsed electric field of 30 kV/cm by the 50 cm treatment chamber has the best effect on pineapple juices characteristic as compared to the other value. The result of this experiment is encouraging and supportive of the better way for pasteurization the pineapple juices and increasing longevity of pineapple juices.

The paper presents the results of series of experimental studies on effects of the type and replacement ratio of fly ash to portland cement on durability of concrete. Specimens made from 28 mixes of fly ash concrete with water binder ratio of 38% to 60% and with replacement ratio of fly ash of 25% to 70% and 5 mixes of portland cement concrete with water cement ratio of 38% to 75% were tested for compressive strengths, drying shrinkage, carbonation and resistance to freezing and thawing. As a results, drying shringkage decreased with fly ash addition regardless of type and replacement ratio of fly ash. Carbonation increased with fly ash replacement ratio, and type 1 fly ash showed higher carbonation. Type 1 and tpye 2 fly ashes showed practically no change in durability factor after 300 cycles of freezing and thawing up to 55% replacement, while type 4 fly ash showed rapid reduction in durability factor up to 40% replacement ratio.

Based on electrical and chemical analysis in oils of some fault transformers in Shenzhen, it indicates that the corrosive sulfur contained in insulating oils may cause faults. Corrosive sulfur would react to copper wire and engender Cu2S during the operation of transformer. Because of the electric characteristic of Cu2S, this substance will penetrate and pollute insulating paper of the wire, and then weaken the insulation intensity. At last it would wear out coil insulation. Experiments indicate that adding passivator to insulating oil is an effective method to solve the problem. Passivator can form a protection layer on the surface of copper, which can avoid copper corrupting and can stop copper deposition in the presence of potentially corrosive sulfur compounds as well.

Sediment microbial fuel cells (SMFCs) produce electricity through the bacterial oxidation of organic matter contained in the sediment, but the power density is limited and needs to be improved. In this study, a new design of a fined-type cathode with carbon cloth embedded partly, as opposed to completely, in SMFCs were utilized. As a result, the design allowing the cathode to contact air will have a positive effect on the power performance and decrease the resistance of the inner system. The power density in the cases where the cathode was about half soaked was about two folds the case where it was soaked completely. Furthermore, SMFCs would also be seen as a driving force in hastening the COD removal because it was about 1.92-folds the COD removal of the cases where SMFCs where not present. These findings can be applied to sewage treatment and improving the power performance in SMFCs.

We report here a facile and green route to prepare graphene-based composites with titanium dioxide-cuprous oxide heterostructure. The as-prepared hybrid was characterized by X-ray diffraction, Fourier transform infrared spectrometer, Raman spectroscopy, and scanning electron microscopy. Photocatalytic degradation of Rhodamine B demonstrated that the as-prepared hybrid has high photocatalytic activities under the visible-light irradiation. We believe that the new graphene-based material would have a potential application in field of energy and sustainabliligy.

A new growth method of graphene directly on the bare dielectric substrates by CVD (Chemical Vapor Deposition) method with Ga-Ni flux as sacrificial layer is reported in this work. Ga-Ni flux acts as not only a container to store carbon atoms which are dissolved from amourphous carbon film when heated, but also as a catalyst to promote the formation of graphene when cooled. In the process of growth, the Ga-Ni flux dewets and evaporates during the rearrangement of carbon atoms, resulting in graphene synthesized directly on the bare dielectric substrates. Scanning Raman Mapping and Spectroscopy, Scanning Electron Microscopy, and Atomic Force Microscopy were adopted to characterize the graphene film.

Introduce content and result of Study on the performance of filtration by Shangdong ceramic media ,and do comparison experiments with general quartz sand , The result shows that it is of low operation cost,high filtration efficiency and good water quality.

We demonstrate a combinatorial graphene oxide (GO) and reduced graphene oxide (rGO) thin film sensor fabricated by spin coating and dip casting method. Thermal treatment was followed to convert graphene oxide into reduced graphene oxide at different temperatures. 100ppm of evaporated methanol was utilized to examine the resistance profile of graphene oxide thin film and reduced graphene oxide thin film. Crystalline phase of GO and rGO were characterized by XRD. Surface roughness was observed by FE-SEM. Obvious opposite sensing property of GO and rGO were observed according to drying conditions.It was attributed to the change in number of radicals and type attached to the edge and surface of graphene oxide during reduction. Authors suggest that control of reduction rate by thermal treatment would be the one of the readiest approaches to enhance the selectivity of gas sensing in terms of direction of reaction.

In this article, graphite oxide was prepared via Hummers method, then reduced by L-ascorbic acid to obtain colloidal suspension of graphene. The resultant graphene was characterized by FT-IR, UV-vis, Raman, XRD, AFM, TEM in detail, and it was found that the the sp2 domain of graphene oxide is restored efficiently, the suspension is very stable and most of the graphene is single-layer. Compared to hydrazine hydrate, L-ascorbic acid has higher deoxygenation efficiency and inclines to gain few-layer graphene and its stable suspensions.

nanohollow graphene oxide spheres have been successfully fabricated from graphene oxide nanosheets utilizing a water-in-oil emulsion technique. High quality graphene oxide nanosheets were prepared from natural flake graphite by oxidation and ultrasonic treatment. Graphene oxide nanosheets were supported by the water-in-oil interface, and self-assembled around water droplets under the assistance of ammonia. With the removal of aqueous ammonia, the graphene oxide nanosheets stacked and condensed at the water-in-oil interface and finally formed a shell structure around the soft template. The nanohollow graphene oxide spheres would be good candidates for catalyst supports, drug delivery and electrode materials in lithium-ion batteries.

The graphite oxide was synthesized with Hummers liquid-phase oxidation method in experiment, and then was reduced to graphene by sodium borohydride, the iron oxide was loaded by dipping method. The catalyst that made reacted in SCR reaction unit in laboratory, the catalysis properties of catalyst was investigated. The experiment results showed that graphene was flake nanometer sheet and presented transparent fold shape, its crystal structure was in order arrangement; the nature of graphene was close to that of raw graphite; their surface function groups were similar; Fe/graphene SCR catalysts had certain catalytic ability in the reaction, the NO conversion rate of catalyst was about 50% while the temperature range was from 200°C to 300°C.

The influence of light radiation with different wavelengths (546, 380, 365 nm) on the coatings of oxidized graphite and its intercalated compound with ammonium dodecahydrododecaborate (NH4)2B12H12 was studied. The transmission and absorption spectra of the coatings were measured before and after irradiation. It was shown that the optical density of the coatings increased because of carbon release (blackening), which was especially strong during UV irradiation. Under the same conditions (wavelength, power, time), the change in the optical density was much larger for the intercalated compound than for oxidized graphite. This can be explained by the presence of the anion B12H12 2- in the former. It is not appropriate to refer to graphite oxide or reduced graphite oxide simply as graphene since their properties are substantially different.

Based on the pilot experiment on quick start-up of filter for removing manganese, amplification experiment was carried out. High concentration aeration and low concentration running were used in this experiment as starting mode. The maturity period of the filter for manganese removal is 9 days. Through the research on the distribution of manganese ions in filter bed by different filtration rate, the result shows a bigger depth of the filter bed is needed with the increase of filtration rate. For raw water with manganese ions concentration of 1.0-1.5 mg•L-1, the highest flow rate that can be handled by this equipment is 0.7 m•h-1. The blockages in filter bed can be washed out under the condition that the back washing intensity is 7.81 L•s-1•m-2 and the back washing time is 5 min. The back washing period of the filter is 13 days.

One approach had been developed for the covalent modification of graphene sheets: amidation and esterification of graphene oxide (GO). Graphene oxide was synthesized by oxidizing graphite in strong acid and lots of oxygen-containing groups, such as hydroxyl and carboxyl processed in the carbon layers, made GO strongly hydrophilic activity as well as certain of chemical activity. This work researched a novel DNA biosensor which fabricated by immobilizing GO on Au electrode modified with mercaptoethylamine(MEA), was investigated by cyclic voltammetry. The results showed that graphite oxide was an excellent material and had a promising prospect in biosensor construction.

Activated cement with the characters of low water demand and high activity was made with Portland cement clinker and dehydrate-gypsum and liquid superplasticizer which were used as grinding additive in the grinding process. Three states of grinding effect exist with correspondence of different dosages of super-plasticizer: the optimal grinding aid dosage, the critical dosage, and the supercritical dosage. First, under the condition of the optimal grinding effect, the activated cement had the maximum strength with little dosage of super-plasticizer and small effect on the performance of activated cement; second, within the critical dosage, the strength of activated cement was similar to the common cement, more super-plasticizer were held and the performance of cement was obviously improved; third, within the supercritical dosage, the strength of activated cement was reduced, but it can accommodate much super-plasticizer, and had a remarkable influence on the performance of cement. The experiment also shows that different properties of low water demand activated cement can be made with admixture of different concentrations of super-plasticizer. Within the allowed limit, use more admixtures was in compile with green environmental protection concept, improve the durability of concrete, and resolve the problem of compatibility between common cement and super-plasticizer, and offered technical support in the produce of commercial concrete by directly use of Portland cement clinker.

The paper is mainly focused on analysis characteristics of lobe pump with three different tooth profiles: Circular, Epi-cycloidal and Circular–Involute–Circular (CIC) rotor profiles. Based on the geometric analysis and mathematical model, the CIC rotor profile combined Circular–Involute–Circular is generated. In this paper, the CFD techniques are used to estimate the effects of tooth profile and lobe number to the pump performance. The simulation results obtained from FLUENT software illustrated that the rotor profile effects remarkably to the pump performance. The outlet pressure of CIC rotor profile is higher than that of the circular and epi-cycloidal rotor profiles. The numerical outcomes also showed that higher rotor’s speed is resulted in higher outlet pressure. Besides, the lobe number of rotor has effect slightly to the pump performance.

The performance of a Plate fin radiator in terms of heat transfer rate and coolant side pressure drop depends significantly on the distribution of coolant through its passages. Uneven flow through the passages i.e. flow maldistribution, can cause local hot spots in the radiator due to high coolant flow in some passages. The flow maldistribution among the passages can be reduced to a large extent by proper optimisation of the header. The present paper investigates the method to optimise the header of a 680 kW radiator to reduce the maldistribution in its passages using Computational Fluid Dynamics (CFD). The analysis was simplified by considering the porous media instead of simulating the exact fin configuration in the radiator. The maximum and absolute values of flow maldistribution factor were considered in this study to determine the effectiveness of the header with respect to flow maldistribution. The flow maldistribution factor was determined based on the individual velocity of coolant in a passage and the average velocity of coolant in all the passages. The methods used for optimisation were rounding the header inlet, tapering the header partially, changing the position of the taper and modifying the end portion of the header. In this paper two parameters, viz., flow maldistribution parameter and absolute maldistribution parameter were considered to measure the maldistribution of a radiator. Due to these optimisations in the header, the maximum and absolute values of maldistribution reduced up to 18% and 45% respectively.

Northeast Extreme Tee (NEXT) beams have been recently developed for the accelerated bridge construction. The skew effect on live load distribution in a NEXT beam bridge, especially with integral abutments, is not clear and shall be assessed. In this paper, various skew NEXT beam bridges are evaluated through validated finite element (FE) analyses with solid brick elements. Parameters as studied include beam section, span length, and skew angle. Per AASHTO LRFD specifications, one- and two-lane loaded cases are examined to obtain the maximum tensile strains in beam stems under the design live loading (HL-93). Unskewed bridges are used as control specimens to compute skew reduction factors (SRF) for moment from the obtained FE strains. The FE- and LRFD-SRFs for moment are compared in terms of figures, which indicate the LRFD-SRFs have good agreements with the FE-SRFs at large. For the majority of the bridges, LRFD-SFRs govern the FE-SRFs. The research findings from this paper are useful for practicing engineers to safely design a skew NEXT beam bridge with integral abutments.

This paper study applicability of non-destructive method of impact echo for diagnosis of high temperature degraded plain concrete. Impact echo method is often used for detection of defects, cracks, and non-homogeneity in constructions. It's based on impact-generated mechanical wave that propagate through the mass of testing specimen and is reflected and partially absorbed by voids and surface. In this paper, we present results of an experiment where test specimens of dimension 0.1 x 0.1 x 0.4 m were created with usage of coarse aggregate 11/22 mm. Specimens has been divided to 7 sets. First set of test specimens were kept at laboratory conditions as a reference. Next six sets were heated up to 1200 ° C. After this heating, the specimens were cooled spontaneously and then tested by impact echo method. We used a steel hammer as an exciter of mechanical wave, which has been transferred to signal by the piezoelectric sensor. Then we analyzed this signal and we focused on transverse waves. Results from non-destructive tests were compared with results from destructive tests.