bluuebunny/crossref_metadata_2025 huggingface dataset:
Photocatalytic activity for degradation of sulfamethoxazole by Bivo4 using visible light
Authors: Nong L X , Nguyen V H , Bach L G , Tran T V , Nguyen T D
Published: March 2020

In this study, B1VO4 photocatalysts have been successfully synthesized by hydrothermal method and were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffusion reflectance spectra (UV-Vis DRS), and Raman spectroscopy. From XRD, Raman, and UV-Vis DRS results, the as-synthesized B1VO4 showed monoclinic scheelite structure and narrow band gap energy (Eg = 2.35 eV). The morphology of as-prepared powder showed a small crystallite size with different shapes. The photocatalytic performances of the as-prepared sample were evaluated by the degradation of sulfamethoxazole under visible light. Also, H2O2 was added to enhance the photocatalytic activity of BiVO4. It has been noticed that 70% photodegradation of antibiotic occurs on the catalyst surface with visible light irradiation. Besides, the effects of pH and organic salts are also discussed in this study.
Selective synthesis of methanol by photoelectrocatalytic reduction of CO2 over PANI-CuFe2O4 hybrid catalyst
Authors: Rezaul Karim K M , Tarek M , Sarkar S M , Ong H R , Abdullah H , Cheng C K , Rahman Khan M M
Published: March 2020

In this work, a hybrid photocatalyst, PANI-CuFe2O4 was synthesized, characterized and used as a photocathode for the photoelectrocatalytic (PEC) reduction of CO2 to methanol selectively under 470 nm wavelength light irradiation at applied potential -0.4 V vs NHE. The PEC results showed that the combination of PANI with CuFe2O4 could increase the rate of PEC CO2 reduction to methanol owing to the increase of CO2 chemisorption at the photocathode surface and at the same time by facilitating the separation of photogenerated electron-hole (e−/h+) pairs during CO2 reduction. The rate of methanol formation was found maximum as 49.2 μmole g−1.h−1 with 73% Faradaic efficiency. The incident photon current efficiency (IPCE) and quantum efficiency (QE) for PEC CO2 reduction was achieved as 7.11% and 23.9% respectively. The PEC results demonstrated that the bias potential played a significant role in the separation of e−/h+ pairs and enhanced the PEC CO2 reduction activity of the hybrid photocatalyst.
Syngas production through steam and CO2 reforming of methane over Ni-based catalyst-A Review
Authors: Arman A , Hagos F Y , Abdullah A A , Mamat R , Aziz A R A , Cheng C K
Published: March 2020

CH4 and CO2 are the two foremost greenhouse gases which are accountable for global warming. Controlling of their emissions and proper utilization has become significant challenge in the field of energy researches. Reforming of CH4 with steam and CO2 is one of the feasible solutions to convert the primary sources of greenhouse gases into syngas. Nowadays, syngas is an essential resource for many industrial applications to produce beneficial value-added products. Besides, it has been referred to as a transition from the fossil fuel towards pure hydrogen energy in the stationary internal combustion engines. Methane reforming with steam or CO2 occurs as a result of the reaction between methane and steam or CO2 in the presence of a catalyst at high temperature. Reaction routes need to be controlled to achieve the desired outputs. To control the reaction path, there are several parameters need to be technically optimized. Reaction kinetic is also necessary to find the reaction rate and select the convenience type of catalyst that can enhance the reaction rate. Catalyst selection and preparation are essential in the reaction because they contribute to the reaction outputs mainly of the syngas ratio (H2/CO). This manuscript is intended to observe the trend of technology improvements on thermodynamic analysis and kinetic study of steam and CO2 reforming of methane reactions over the Ni-based catalyst. It also presents the evaluation of the catalytic effect/properties and their relationship with the performance of the catalyst needed for the design and suitable for steam and dry reforming of methane reactions.
A novel enhancement for the start-up of methane fermentation reactor by inoculating the acclimated sludge as a seeding material
Authors: Dinh N. T.
Published: March 2020

This study aimed to evaluate the strategy for accelerating the start-up of anaerobic reactor treating glycerol. The experiment was carried out for 25 days duration in two cases: (1) gradually increase of glycerol content in substrate from 33% to 67% to 100% after 13 days (runs: G1 and B1); (2) feeding with 100% glycerol content in substrate from the start (runs: G2 and B2). G1 and G2 were inoculated by one third of acclimated granular sludge to treat glycerol and two third of granular sludge taken from a brewery wastewater treatment system. In results, the average methane production rate (L CH4 L−1 day−1) of runs G1; B1; G2; B2 was 0.56; 0.39; 0.42; and 0.14, respectively. G1 was the best performance among runs. G2 and B1 were unstable during the start-up. B2 was fluctuant throughout the duration time. The methane production rate of G1 and B1 was highly correlated and DNA concentration of Genus Trichococcus in the sludge. This study suggests that gradual feeding substrate during start-up could provide a stable performance compare to the shock feeding. Acclimated sludge which contained functional microorganisms of treating glycerol could accelerate the start-up of new anaerobic digester.
Immobilization of Alcohol Dehydrogenase in membrane: Fouling mechanism at different enzyme concentration
Authors: Ismail F H , Marpani F , Him N R N
Published: March 2020

Fouling induced enzyme immobilization on polymer membrane with controlled variables can retain enzyme stability and performance. In this study, the effect of enzyme concentration towards the fouling-induced enzyme immobilization was investigated. Alcohol dehydrogenase (ADH) was used as model enzyme to be immobilized on poly(ether) sulfone (PES) membrane at different concentration (0.05, 0.10 and 0.20 g/L). The transmembrane pressure and pH were fixed at 2 bar and pH 7 respectively during the process takes place. The result shows that higher enzyme concentration gives higher loading efficiency with 83.95%. Hermia’s model predicted that standard and intermediate blocking dominating the fouling mechanism at all enzyme concentration tested.
Improvement of ionic conductivity of titanium dioxide incorporated PVDF-HFP/cellulose acetate electrolyte membrane
Authors: Sugumaran J , Ahmada A L , Zaulkiflee N D
Published: March 2020

This work aims to improve the lithium ion conductivity by incorporating titanium dioxide (TiO2) in Polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) and Cellulose acetate (CA) electrolyte membrane. The morphology of the prepared membrane was observed using Scanning Electron Microscope (SEM) and the ability of the membrane to uptake liquid electrolyte was also tested. The SEM results show that the electrolyte membrane has porous, interconnected network but the addition of TiO2 resulted in a reduction in porosity. Despite reduced porosity, the electrolyte uptake of PVDF-HFP+CA+TiO2 is the highest among others with value up to 287.5%, this increase is due to the improvement in the amorphous phase. The ionic conductivity increases by 21.29% compared to PVDF-HFP electrolyte membrane with the addition of TiO2. The generation of more mobile lithium ion and prevention of crystallization of polymer through Lewis acid-base reaction leads to improvement in ionic conductivity.
A Review on Surface Characterization Techniques of Polymeric Membrane in Forward Osmosis
Authors: Aziz Siti N. S. A. , Seman Mazrul N. A. , Saufi Syed M.
Published: March 2020

Forward osmosis (FO) is an emerging osmotic process that has been extensively investigated in the past decade. There are many literatures, discussing on the available methods in producing FO membranes as well as researches that emphasis on the type of FO membranes. The quality of the FO membrane often valued based on its intrinsic parameters and its morphological characteristics. Unlike the intrinsic parameters, the surface characteristics regularly described in adjectives thus it is hardly to be consistent. This paper presents a comprehensive review on surface characterization specifically for FO membranes. Regardless the types of FO membranes, the surface characterization comprises of FTIR, XPS, FESEM/SEM, AFM and contact angle were discussed in the way that how the findings should be reported. Thus, through this work, the relevant discussion that should be measured and included when deliberating the analysis result for FO membranes is presented. Insufficient and misinterpreted characterization data might have not changed the novelty fact of the research, yet it may lead to lower its impact. A strong connection between the intrinsic values and surface characteristics would have been compromised as well.
Mechanical and thermal properties of polyurethane/neoprene/graphene blends
Authors: Syahir A , Mat Piah M B , Alhadadi W , Hafidzah F , Desa M S Z , Noor M Z M , Norazmi M , Ramli A
Published: March 2020

This work investigated the properties of the polyurethane/neoprene/graphene nanocomposites blends specifically in mechanical and thermal aspects for solid ankle cushion heel (SACH) foot in the prosthetic application. The aim of this work was to study the effect of neoprene and graphene contents in mechanical and thermal properties of polyurethane/neoprene/graphene blends. Polyurethane is one of the most frequently used polymers in the medical devices, footwear, automotive and construction industries. Polyurethane which is high mechanical strength, high thermal withstands and flexibility was blended with the additives, neoprene and graphene to reduce the rigidity and enhances the mechanical properties for a prosthetic foot. A solution mixing method was used to prepare the samples with different formulations of polyurethane, neoprene and graphene. The samples were analyzed and characterized in terms of mechanical, thermal and morphology properties. The result shows that the optimum composition blended with 97 wt% polyurethane, 2 wt% neoprene and 1 wt% graphene. The sample possesses high tensile strength (14.38 MPa) and high Young’s modulus (1.11 MPa), high thermal stability, elastic and flexible. The use of a low amount of graphene in polyurethane and neoprene blend has been demonstrated to enhance the mechanical and thermal properties of the nanocomposites.
Sugar profile and enzymatic analysis of stingless bee honey collected from local market in Malaysia
Authors: Julika W N , Ajit A , Ismail N , Aqilah N , Naila A , Sulaiman A Z
Published: March 2020

Commercial honey is widely available in the market, raising questions whether the honeys are good in quality or otherwise, Thus, this research was designed to compare the quality of harvested stingless bee honey and commercial honey available in the Malaysian market by measuring their sugar profile and enzyme activity. The analysis showed that the honey contained moisture between 16.6% - 32.1%, various sugar starting with fructose (15.03 – 48.44 g/100 g), glucose (12.16 – 40.09 g/100 g), sucrose (<0.01 – 7.29 g/100 g), Fructose + Glucose (F+G) (15.03- 80.25 g/100 g), Fructose/Glucose (F/G) (0.78 – 1.63), and G/W (0.47 – 1.89). Also, diastase activity and Invertase activity of the honey varied from 1.82 to 6.11 DN and 0.27 IN to 4.94 IN, respectively. Eight honey samples including harvested honey, H. Itama and G.Thoracica showing comparable results with past studies and within the limits of Malaysian Standard. However, all honey samples demonstrate lower enzyme activity suggesting that honey from stingless bee has low enzyme activity compare to Apis mellifera honey.
Effects of Petroselinum crispum extract versus fat diet and Dexamethasone induced organ injuries in mice
Authors: Muttalib Mohammed Abdul , Albadri Haider M.Badea , Hussein Hasan Fadhil
Published: March 2020

Petroselinum crispumis a herb belonging to the Apiaceae family,it has been usually used for the management of many inflammatory disease due to many pharmacological effects of corticosteroid with a strong anti-inflammatory and immunosuppressant properties (ex. dexamethasone), it is famous to cause side effects. It was clearly observed that dexamethasone could induced liver renal and increase the lipid profile in mice. The Petroselinum crispum methanol extract was prepared by soaking of 200 g of each of the pure dry in 1 liter of 90% methyl alcohol with shaking for 5 days, The selected animal groups (eight animals per each group) were grouped as follows Positive control group 1, negative control group 2, group 3 (10%) Petroselinum crispum treated and group 4 (20%). Petroselinum crispumtreated group it was found that Petroselinum crispumhas a clear ant atherosclerosis and a potent liver protection effects.
The effect of Roselle calyces extract on the chemical and sensory properties of cupcakes
Authors: Thanh V T , Tran Nhi Y T , Linh N T V , Vy Tran Anh , Truc Tran Thanh
Published: March 2020

Roselle calyces (RC) are a valuable crop for export and manufacture of a typical drink in Vietnam. The RC is widely applied as a natural colorant in different fields such as food and pharmaceutical industries. The objective of this research was to determine the effect of extraction parameters on the nutritional value and sensibility of cupcake added with RC. Examined indicators included lipid, moisture, pH, protein, and ash. Moreover, the sensory properties of cupcakes formulated with Roselle calyces extract were also determined. Compared with the control cupcake, the RC-added cupcake exhibited higher content of moisture, protein, and ascorbic acid, achieving 30.16 ± 0.25, 2.76 ± 0.07 and 37.65 ± 0.64 respectively. In contrast, the level of pH, ash, and lipid experienced a marginal drop, achieving 7.02 ± 0.25, 1.05 ± 0.13 and 14.78 ± 1.01 respectively. Moreover, the Roselle cupcake had 3.74 ± 0.02 mg/L anthocyanin content. The percentage of retention of anthocyanin content at 180°C for 20 minutes was 60.53 ± 0.48. RC cupcakes have high sensory scores (P<0.05) comparing with control RC cupcakes. RC cupcake can be a functional food which has a cost- effective advantage.
Bioelectrochemical Cell (BeCC) integrated with granular activated carbon (GAC) in treating spent caustic wastewater: Effects of solid retention time (SRT) and organic loading rate (OLR)
Authors: Fazli N , Mutamim N S A , Rahim S A
Published: March 2020

The study aims to treat spent caustic wastewater by using a bioelectrochemical cell (BeCC) integrated with Granular Activated Carbon (GAC) as the bacterial attachment medium. BeCC is a bioelectrochemical reactor which employs microorganisms for substrates degradation and has the capacity to produce energy simultaneously. Microbial Fuel Cell (MFC) is also known as the bioreactor that could treat wastewater while producing energy. However, the BeCC reactor in the present study is more cost effective than an MFC reactor, since the BeCC was operated without the employment of a proton exchange membrane (PEM). The reactor was operated in a hybrid of anoxic and aerobic conditions whereby a baffle is used as the separator to minimize the oxygen transfer from the cathodic to the anodic side of the reactor. For enhancement of the BeCC performance, 10 g of suspended GAC was added into the BeCC reactor. The use of the suspended GAC is to allow higher surface area available for bacteria attachment. The study determined the best operating solid retention time (SRT) and organic loading rate (OLR) of BeCC in treating spent caustic wastewater and its performance throughout 30 days of operation was evaluated based on its Chemical Oxygen Demand (COD) removal and open circuit voltage (OCV). For SRT study, BeCC was tested at various SRT of range within 10 to 30 days whereas for OLR study, BeCC was tested at various OLR of range within 700 to 900 mg COD/L.d. From the study, the highest COD removal were 94.17% and 92.7% achieved at SRT of 30 days and OLR of 700 mg COD/L.d respectively. Whereas for energy recovery, the highest OCV were 336.4 mV and 362 mV achieved at SRT of 20 days and OLR of 800 mg COD/L.d respectively. Biochemical bacteria identification test was also carried out to identify the bacteria morphology attached on GAC in the BeCC at SRT of 20 days with 700 mg COD/L.d of OLR and it is found that Klebsiella Oxytoca was the dominant bacteria attached on the GAC.
Application of Matlab to Data Processing of Buckling Experiments
Authors: Zhou Jiahui , Yang Peng , Sun Jie , Shi Chenyu , Xue Jianghong
Published: March 2020

In this paper, matlab programs were written to efficiently process the experiment data for buckling and post-buckling of delaminated composite beams. In the experiments, data collected from 810 Material Test System (MTS) and from dial indicator were sampled at different frequencies, thus were not matched with each other in time. To solve this problem matlab programs were developed. It shows that using the developed program, the experiment data from the two testing systems are corresponding and truly reflect the changes of mechanical parameters in the buckling and post-buckling process of specimens in the experiments.
Exploring the Optimal Growth Parameters of Al2O3 Grown by Atomic Layer Deposition
Authors: Li Shuping , Ren Zeqian
Published: March 2020

High quality Al2O3 thin film is grown by atomic layer deposition (ALD). The influence of growth parameters such as growth temperature and purge time on the surface morphology, dielectric constant and so on have been investigated. It is found that Al2O3 thin film at a flow rate of 150 sccm, H2O flow rate of 150 sccm, pulse time of 0.1 s, purge time of 6 s, cycle period of 450 times and growth temperature of 150°C, exhibits the optimal material quality with a growth rate of 0.79 Å/cycle, a root-square surface roughness (RMS) of 0.152 nm and a capacitance of 13.8 nf.
General Stress Fields of Orthotropic Plate with Mode II Crack
Authors: Zhang Long , Jia Purong , Suo Yongyong , Jia Cheng
Published: March 2020

The plane crack problem of the orthotropic plate is discussed for the shear loading. The solution of this problem is mainly achieved by the complex variable method. Essential equations are introduced fully on the basis of linear elastic mechanics. The stress functions have been given to meet the needs of shear mode II crack states for orthotropic materials. The formulae for stress fields are derived by the complex functions in two cases. With the simplification of relative functions, the expressions of the singular stress fields in the crack-tip are determined by the real functions.
The Effect of Temperature on Properties of CNTs Grown by Chemical Vapor Deposition
Authors: Li Hui
Published: March 2020

In this article, the carbon nanotubes (CNTs) grown at different temperature by thermal chemical vapor deposition(T-CVD) have been reported, while the effect of growing temperature and catalyst annealing on the quality of CNTs has also been investigated. The longest CNT bundles were grown at the temperature of 730°C by Scanning Electron Microscopy (SEM) images and the better quality of CNT bundles were achieved at higher temperatures of 850°C by Raman spectroscopy.
Optimal Combined Process for Treating Oily Wastewater Using Membrane Distillation Technology
Authors: Cui Xiangxu , Ge Yunzhi , Yu Ruoting , Dong Yan , Dai Xiaodong
Published: March 2020

The membrane distillation technology used in this paper is a new type of wastewater treatment technology, which is now mostly used in seawater desalination and wastewater treatment. The traditional oily wastewater treatment methods have problems such as large energy consumption and low removal rate. It is proposed to use vacuum membrane distillation technology to use a large amount of waste heat in wastewater as the driving force for mass transfer to treat oily wastewater, which not only saves energy, but also effectively counteracts the problem. The solid particles, hydrocarbons and other pollutants contained in the wastewater are intercepted, so that the treated water quality reaches a certain degree of purity and meets the discharge standards. In this paper, the membrane microporous membrane used in the process of membrane distillation is targeted at the problem of membrane pollution Improved to achieve the purpose of reducing costs and increasing membrane life.
Effects of Shot Peening on Fatigue Life of Ground Component of 7075-T6 Aluminum Alloy
Authors: Cheng Xiuquan , Zhang Junhao , Sheng Xiangfei , Xia Qinxiang
Published: March 2020

The aircraft corroded components can continue to be used after removing the corroded portion by grinding and strengthening the ground area by shot peening. The finite element analysis model of the ground specimen with complex shape surface was established based on ABAQUS software. The residual stress distributions under three conditions of without shot peening, ground surface shot peening and three surfaces shot peening were analysed. On this basis, the cyclic alternating load was introduced into the shot peening model, and the fatigue analysis was carried out based on MSC. Fatigue software. The result shows that the position of the maximum tensile stress moves from the surface to the subsurface of the ground specimen after shot peening; shot peening conditions will affect the location of the crack sources, the propagation direction of the crack; with the increasing of the numbers of peened surface, the location of stress danger point shifts from ground surface to side surface or sub-surface, and the crack propagation velocity decreases. All of these increases the fatigue life. The experimental results conform well to the simulation one.
Diamond Scintillation and Quality Evaluation
Authors: Zhang Zhongkui , Guo Ying , Liu Qiutong , Shen Yijiang
Published: March 2020

The quality of a diamond is not only affected by the 4Cs but also affected by fire and scintillation. The relationship between the color, clarity, fluorescence, and scintillation of a diamond is obtained by associating its scintillation area and gemological characteristics. Take images of 18 round bright cut diamonds in total, for each to rotate 30° to take one and get 12 images by rotating a circle. Rotate the images to the same angle, cut out the square image of 1000*1000 pixels, then calculate the color difference of the image of adjacent angles, and then judge whether scintillation occurs at each point to get the scintillation area of the diamond. The results showed that the lighter the color, the better the clarity and the weaker the fluorescence, then the larger the scintillation area and the more obvious the scintillation. This indicates that the scintillation area has a certain reference value for diamond quality evaluation.
Dynamic Response of Biodynamic Model Seated on a Crashworthy Seat with Composite Absorber
Authors: Li Na , Fu Yi
Published: March 2020

This paper presents an energy absorber consists of an inward folding of composite tube. There is no composite debris overflow after the composites collapsing and the debris will fill in the inner of tube to increase the energy absorption. The absorber maintains integrate during crushing and then could be used in a crashworthy structure. Impact tests were conducted to explore the energy absorption performance. To investigate the application of the absorber to the shock-resistance of the seat in the helicopter, a five-degree-of-freedom nonlinear biodynamic model corresponding to 50th-percentile male occupant was setup. Simulations on the responses of the biodynamic with and without absorber were conducted, and the results present effect of the absorber on shock-resistance.
Design of the Transmission Device of the Some Type of the Manipulator
Authors: Ma Yan , Xu Jingxi , Jiang Xingqiao
Published: March 2020

The transmission part of a manipulator is presented in the paper. The part of manipulator transmission device is analysed and the part of manipulator transmission device is designed. Design and calculation of suction hand is represented. The driving motor is checked, the calculation of the equivalent moment of inertia of the transmission system is gained, the motor moment frequency characteristic is presented, and the starting torque of the stepping motor is determined. And the schematic diagram of the overall structure and the schematic diagram of the motor connection plate is presented. The theoretical support and design reference for the design of the transmission device of the manipulator is presented in the paper.
Three-dimensional Simulation of Turbulent Rectangular Jet Spreading Technology of Carbon Fiber Bundle
Authors: Chen Jinliang , Niu Xuejuan , Zhang Zhun
Published: March 2020

In order to smoothly spread large-sized carbon-fiber bundle, hot-jet blower is added to a turbulent spreading platform to conduct pre-spreading process. To achieve the best spreading performance, CFD model of the blower are simulated based on the Reynolds average Naiver-Stokes equation. The influence of the relevant geometric parameters and process parameters on the internal flow field are analyzed. The distributions of streamline, surface temperature and air pressure under different working condition are characterized and compared parametrically. The effective area of the nozzle directly contacts with fiber wall surface. Simulating model has been built and crossover experiments have been carried out on the spreading platform to investigate and optimize the influence of jet distance, nozzle air pressure and hot-jet temperature on the spreading performance of fiber bundle. According to the experimental data and simulating results, relevant geometric parameters and process parameters of the nozzle are optimized.
Bi-directional Evolutionary Structural Optimization of Continuum Structures with Multiple Constraints
Authors: Gao Yunkai , Ma Chao , Feng Bo , Tian Linli
Published: March 2020

Most of the structural topology optimization problems involved in practical engineering applications are problems with many constraints. Thus, this paper presented an improved bi-directional evolutionary structural optimization (BESO) method for problems with many constraints. Slack variables were introduced to transform the inequality constraints into equality constraints. Then the Lagrange multiplier method converted the multi-constrained optimization problem to an unconstrained optimization problem and an advanced multiplier calculation was proposed. Elemental sensitivity numbers were derived according to the obtained multipliers. The design variables were updated by the BESO method. One numerical example that aimed to minimizing the structural mean compliance and involved volume, fundamental frequency and displacement constraints was used to validate the proposed method. The new method extends the BESO method to topology optimization that has a number of constraints, such as volume, displacement and frequency constraints.
Parametric Design and Numerical Control Simulation of Cylindrical cam Based on Ug8.5
Authors: Ye Xuanlin
Published: March 2020

This paper introduces the method and process of parametric modeling and numerical control programming simulation processing of cylindrical cam by using ug8.5 software, improves the design, manufacturing efficiency and precision of cylindrical cam, and realizes the serial design of cylindrical cam. It has been proved by practice that the performance of cylindrical cam is stable and efficient, which greatly shortens the machining cycle of cam and improves the efficiency.
Synthesis and Electrochemical Performance of Nano-sized CuO/TiO2 for Lithium-ion Batteries
Authors: Liu Guangfu , Liu Kuiren , Shao Zhongbao , Li Xuetian
Published: March 2020

CuO/TiO2 nanopowder was successfully synthesised by precipitation method. XRD, SEM and galvanostatic testing were applied to study the crystal structure and electrochemical performance of CuO/TiO2. The results showed that the prepared sample was highly-crystalline and exhibited high capacities and well cycle stabilities. The initial discharge capacity of CuO/TiO2 reached 566.5 mAh/g, and retained at 375.9 mAh/g after 20 cycles at 0.1C-rate. It is implied that CuO/TiO2 nanopowder prepared by precipitation method coulde be used as an anode material for lithium-ion batteries.
Direct Electrodeposition of Zno Nanosheets Film on Plastic Substrate
Authors: Xiao Chuanhai , Sun Shang , Lai Qi
Published: March 2020

A novel and simple method to directly assemble nanostructures onto plastic substrate via a quasi-2D electrodeposition approach was proposed. It was demonstrated that such synthetic method was feasible for flexible electronics, as exemplified by the fabrication of ZnO nanosheets film photoresponse devise onto flexible transparent, polyethylene terephthalate (PET) substrate that can withstand bending. This direct assembly strategy is general to other nanostructures onto plastic substrate which can be electrodeposited.
Tyre Side-Slip Deformation of Dual-Steering Multi-Axle Vehicles Based on Steady-State Cornering
Authors: Wang Yunchao , Hu Zhichao , Li Bo , Li Zixu
Published: March 2020

It is well-known that the tyre side-slip deformation is a static indeterminacy problem for the full-vehicle tyres. For the dual-steering multi-axle vehicles on steady-state cornering, it is a closed and dissipative system in a stable dynamic balance state. Therefore, the minimum energy dissipation rate principle is adopted to solve the above indeterminacy problem. Moreover, a new method is proposed to develop a formula for calculating the tyre side-slip angles of the vehicles with dual steering systems (DSS). The validity of the formula is examined using the formula from literature and simulation results of the reference model
Key Structural Parameters Analysis of Effective HydroClean Drill Pipe
Authors: Tao Chen , Yuguo Jin , Feng Chen , Qinfeng Di , Wenchang Wang , Qing Li
Published: March 2020

In directional well, horizontal well and extended reach well, there is a common problem that cuttings bed is easy to form in the process of drilling in highly deviated section. To solve this problem, an Effective Hydro Clean Drill Pipe (EHCDP) is designed, and the flow characteristics of the annular flow field under the action of EHCDP are analyzed by using computational fluid dynamics (CFD) simulation technology. On this basis, the key structural parameters affecting the swirl characteristics of EHCDP are studied. The results show that when the number of spiral grooves is 3, the axial and tangential velocities of annular fluid in spiral groove section will be greater, which is conducive to carrying and removing cuttings. Compared with the inclination angle of spiral groove with 1000 mm lead, that of spiral groove with 500 mm lead is larger, which has more obvious stirring effect on flow field, and the effect of cuttings removal is better. In addition, the spiral groove with 90 degree groove angle is more conducive to cuttings removal than the spiral groove with 30 degree groove angle. The results can provide a basis for the selection and optimization of structural parameters of spiral groove.
Facile preparation of cellulose nanofibers prepared by TEMPO-mediated oxidation
Authors: Tanpichai S
Published: March 2020

Cellulose nanofibers (CNFs) with width of 20 nm and lengths of up to several µm were fully disintegrated from water hyacinth (Eichhornia crassipes) with aids of the 2, 2, 6, 6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation and mild-mechanical treatment. TEMPO-oxidized CNFs were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). FTIR reveals the conversion of C-6 hydroxyl groups to sodium carboxylate groups, and lower thermal degradation was obtained from the TEMPO-oxidized CNFs in comparison to untreated cellulose fibers. The as-prepared TEMPO-oxidized CNFs might be possibly used in packaging and composite applications.
The analysis of a chilled beef supply chain for developing strategic improvement
Authors: Neisyafitri R J , Ongkunaruk P
Published: March 2020

The growth of population and economics are factors that affect the increasing demand for livestock products in Indonesia. Beef and chicken are the most consumed meat in Indonesia with an average meat consumption of 2.72 kg per capita per year and there is an increasing trend. Currently, the domestic production of beef is only about 45% percent of the demand, the rest of the demand will be fulfilled by importing live cattle and frozen meat, mainly from Australia. The beef supply chain is quite complex and long. The available infrastructures still need to be improved in order to deliver the beef quickly and handled under appropriate cold chain. Our objectives are to identify the business process of the abattoir in the chilled beef product cold chain, to analyze the problem, and to propose some recommendations for their strategic improvement. The observation and in-depth interviews are conducted. Then, the result is analyzed by using Integration Definition for Function Modelling (IDEF0) to figure out the current situation and the activities in the abattoir. Based on the result, it is found that inventory management and temperature controlling are the major issues in the chilled beef cold chain that need to be monitored and controlled. This suggestion would be able to improve the efficiency of a chilled beef cold chain in Indonesia.
Characterization of polylactic-epoxidized natural rubber/modified cellulosic fiber biocomposites with different silane coupling agents
Authors: Kadea S , Seekaew J , Thongmala S , Hedthong R , Khanoonkon N , Witayakran S , Chatakanonda P , Chollakup R , Kittikorn T
Published: March 2020

A purpose of this research was to investigate a potential of two differently modified cellulosic fibers for applying as reinforcing fillers in polylactic acid (PLA) and modified epoxidized rubber (ENR) base of biocomposites. Coupling agents including 3-(trimethoxysilyl) propyl methacrylate and (3-aminopropyl) trimethoxysilane were used in order to modify cellulosic fibers. These fibers were compounded with PLA-modified ENR (modified by bisphenol A diglycidyl ether) in an internal mixer and fabricated to composite sheets using a compression molding, respectively. The formulations of biocomposites were designed by weight ratio of PLA (85%): modified ENR (5%): the cellulosic fiber (10%). Accordance with the results of mechanical property analysis of their biocomposites, the modifications of cellulosic fibers with both silane types significantly improved flexural, hardness and impact properties of PLA-modified ENR based biocomposites. However, the methacrylate-silane modified cellulosic fiber provided the greatest increase in flexural properties while the amino-silane modified cellulosic fiber resulting in the highest value of hardness and impact resistance of all biocomposites. Oil absorption test of biocomposites was also investigated in this research in order to evaluate its possibility to use under oily environment. After 168 hours of experiment, the amino-silane modified composite exhibited the highest oil absorption among all materials. This result indicated the most improvement of hydrophobicity of modified cellulosic fiber by (3-aminopropyl) trimethoxysilane.
Synthesis of Graphene Foam Filter by Chemical Vapor Deposition Using Palm Oil as a Carbon Source for PM2.5 Capture
Authors: Naksakul T , Sunpong P , Ruammaitree A
Published: March 2020

Particulate matter which has aerodynamic diameter less than 2.5 µm (PM2.5) has seriously impacted on human health such as cardio-respiratory diseases. Graphene foam is a 3-dimensional graphene, in which carbon atoms are arranged into a honeycomb lattice. In this study, PM2.5 capture using graphene foam filter is demonstrated. The graphene foam is synthesized by chemical vapor deposition using nickel foam and palm oil as a template and carbon source, respectively. After that the sample is soaked with FeCl3 to dissolve the nickel foam template. The presence of graphene on nickel foam is confirmed by Raman spectroscopy. The morphologies of graphene and PM2.5 particles are measured by field emission scanning electron microscope. The element composition of PM2.5 is investigated by energy-dispersive X-ray spectroscopy (EDX). The results show that graphene foam can capture various types of PM2.5 particles (such as aluminium, silicon, phosphorus and so on) without additional energy.
Y2BaCuO5 Particle Size Control via Ultrasonication and its Effect on Bulk YBa2Cu3Oy Superconductor
Authors: Pinmangkorn S , Miryala M , Arvapalli S S , Murakami M
Published: March 2020

Recently, bulk LRBa2Cu3Oy (LRE: Y, Gd, Sm, NEG) superconducting materials became a popular choice for engineering applications such as high-field magnet systems for medical devices, rotating machine, magnetic bearings, etc. YBa2Cu3Oy (Y-123) is a trending high temperature superconducting material with a high critical temperature around 91 K. The superconducting performance of bulk YBa2Cu3Oy (Y-123) can be dramatically improved by controlling initially added Y2BaCuO5 (Y-211) secondary phase particles and optimizing its processing conditions in the top seeded melt-growth (TSMG). In this work, we employed a low-cost ultrasonication technique to control size of initially added secondary phase Y-211 particles. The ultrasonication time is varied from 20 to 80 minutes along with a 20 minutes interval while maintaining constant power of 300 W and 20 kHz frequency. We had successfully prepared nanometre sized secondary phase Y-211 particles. Top seeded melt textured bulk Y-123 (20 mm diameter) were prepared with utilizing refined Y-211. The magnetization measurements exhibited a sharp superconducting transition temperature with Tc, onset
around 91 K. Critical current density (Jc
) and trapped field measured at 77 K exhibited higher value in bulk prepared with Y-211 secondary phase particles ultrasonicated for 80 minutes. The highest trapped field of 0.42 T at 77 K was recorded 0.3 mm above centre of the Y-123 bulk’s surface. The self-field critical current density was around 47 kA/cm2 at 77 K (H//c-axis). The present results demonstrate that the performance of bulk Y-123 can be improved by controlling Y-211 secondary phase particle size via a low cost ultrasonication process.
An accelerated biodegradation of Poly(lactic acid) by inoculation of Pseudomonas geniculate WS3 combined with nutrient addition
Authors: Boonluksiri Y , Prapagdee B , Sombatsompop N
Published: March 2020

This study aims to develop an efficient method for accelerating the biodegradation rate of Polylactic acid (PLA). A combined use of PLA-degrading bacterium, Pseudomonas geniculate WS3 and nitrogen source or enzyme inducer to accelerate biodegradation of PLA was proposed. PLA films were prepared and submerged in basal salt medium (BSM) amended with ammonium sulfate, soytone, sericin or sodium lactate and inoculated with P. geniculate WS3 for 30 days. The results showed that the highest percentage of PLA film-weight loss was found in the treatment of soytone addition, followed by sodium lactate addition. PLA films in culture broth with P. geniculate WS3 and soytone were cracked and broken down into small fragments within 20 days. In addition, increasing the lactic acid content as a monomer of PLA in culture broth was directly correlated with increasing the percentage of PLA film-weight loss. It could be concluded that a combined use of P. geniculate WS3 and soytone exhibited a high potential to significantly accelerate the PLA biodegradation under the submerged condition.
Effect of sintering temperature on microstructure of TiO2 scaffold
Authors: Yanawarutwong S , Thunyakitpisal P , Kashima D P
Published: March 2020

Due to an excellent biocompatibility of titanium dioxide (TiO2), it is promising to use as scaffolds for inducing bone formation. The well-interconnected pore scaffolds were fabricated by sponge replication method in order to promote osteoblast ingrowth and vascularization. The viscosity of the slurry was adjusted by addition of calcium chloride (CaCl2) which led to more uniformity and densification. The effects of sintering temperatures on microstructure were analyzed by scanning electron microscope (SEM) and microcomputed tomography (Micro-CT). Our experiments showed that the higher sintering temperature increased the grain size and more uniformity of the scaffold. Furthermore, the struts became more rounded and microcracks were not observed which probably correlated to the higher density of scaffold. Thus, it is suggested that optimization of sintering temperatures might allow better control of grain growth and result in more microstructural uniformity.
Confirmation molecular structure of the Hevea rubber molecule and its effects in storage hardening
Authors: Theamsawade P , Kumarn S , Sakdapipanich J
Published: March 2020

Lipids are the one of major non-rubber components discovered in natural rubber (NR) latex, which reported to be the significant parameter affecting the properties of NR [1, 2]. Our previous work suggested that lipids are the major factor dominate branching formation in NR [3], which could bring about the change in physical properties of NR during long term storage as called storage hardening (SH) phenomenon. However, lipids found in NR consist of neutral and polar lipids, i.e., phospholipids and glycolipids [3]. The information on types of lipids affecting the storage hardening behaviour in NR have not yet been investigated. Therefore, the aim of this work was to study the relationship between types of lipids on the gel formation in NR under accelerated storage. In the present work, natural rubber was treated by deproteinization, acetone extraction, chloroform:methanol extraction and transesterification for eliminating proteins, neutral lipids, polar lipids and linked lipids, respectively. The molecular structure of the rubber samples and the remaining non-rubber components were analyzed using nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR). Moreover, the rubber samples were subjected to study the storage hardening behaviour under accelerated condition using phosphorus pentoxide (P2O5).
The modification of steel belt layer of airless tire for finite element analysis
Authors: Phromjan J , Suvanjumrat C
Published: March 2020

The airless tire can be considered as composite structure since it composed of several components with different materials for desired performance. The three main components of airless tire are rubber tread, shear band and polymer spokes. The shear band composed of three complex steel belt layers and should be considered as a sub composite structure. The finite element method can be used in designing and development of airless tire. However the diversity of materials in each component including the complex sub structure resulted in complicate modelling and consuming analysis time. Thus, the large computational resources are required to analyse those components. In this research, the simplification of modelling and analysis of airless tire was attempted by modification of steel belt layers. The Mooney-Rivlin hyperelastic model was used to describe the material properties of tread and spoke. The constitutive model constants were obtained by tensile and compressive test according to ASTM D412 and D575 standards, respectively. The simplified belt, which was developed by homogenization approach, was integrated into shear band component. The airless tire model with modified steel belt layers can be used to reduce the model complexity and analysis time while yields accurate results.
Efficient removal of methylene blue by low-cost and biodegradable highly effective adsorbents based on biomass in the fixed bed column
Authors: Sasaengta D , Panapoy M , Chaiyut N , Ksapabutr B
Published: March 2020

The adsorptive ability of sustainable biomass (spent coffee ground (SC) and water hyacinth (WH)) and activated biochar derived from WH to remove methylene blue (MB) from aqueous solution was evaluated under continuous fixed-bed column. Morphological structure and functional groups of WH and SC were determined by SEM and FTIR, respectively. The SEM showed the presence of porous structure of WH, whilst FTIR confirmed the presence of more hydroxyl groups at the WH surface, resulting in higher MB adsorption. A series of column experiments were performed with varying bed height and initial MB concentration. To determine the breakthrough curves and characteristic parameters for process design, Yoon-Nelson, Thomas and modified Dose-Response models were applied to experimental breakthrough data. The MB adsorption was dependent on the bed height and initial MB concentration. An increase in bed height resulted in improved adsorption capacity. With increasing initial MB concentration, the adsorption capacity decreased. The maximum adsorption capacity (Q0) of ∼391 mg/g by WH (at 0.75 cm bed height and 300 mg/L initial MB concentration) and ∼393 mg/g by its activated biochar (at 2 cm bed height and 200 mg/L initial MB concentration) was observed. The results showed that WH gave comparable MB adsorption capacity with a greater cost-effectiveness.
Enhanced mechanical performance of cement board composite reinforced with coconut coir fiber and tire rubber waste
Authors: Thepthong C , Ksapabutr B , Chaiyut N , Panapoy M
Published: March 2020

This work aimed to study the use of tire rubber waste (TW) and coconut coir fiber (CF) as the recycled material and partial replacement of cement and asbestos to produce cement board composite and obtain optimal replacement level. The amounts of TW and CF were the variables in this experimental study. Various mixtures were produced by partial replacement of cement with TW at different percentages (2.5, 5.0, 7.5 and 10%) and with CF at different percentages (1, 2 and 4%) using a fiber length of 3 cm. The mechanical and physical properties of the cement boards were evaluated. Both the flexural and impact strengths of the cement boards increased with an increase in the content of TW and CF. The mechanical properties of the cement composites based on the combination of TW and CF were significantly better due to the synergy of TW and CF additions. Moreover, the results also showed that the density decreased with increasing in TW and CF. Therefore, TW and CF can be utilized as a good replacement of cement for cheap, lightweight and eco-friendly reinforced cement boards.
Phase assemblage and properties of laser cladded TixCrFeCoNiCu high-entropy alloy coating on aluminum
Authors: Li Yanzhou , Shi Yan
Published: March 2020

The TixCrFeCoNiCu(x:molar ratio,

x
=
0
,

0.2
,

0.5
,

0.8
,

or

1.0

) coating was depositd on aluminum by laser cladding. The phase structure, microstructure, hardness, wear resistance and corrosion resistance were studied. The results show that with the increase of Ti content, the phase structure of the TixCrFeCoNiCu coating changes from single FCC to FCC + B2, and FCC + Laves phase. When Ti is increased to 1.0, cracks appear in the coating. The hardness of the TixCrFeCoNiCu coating is enhanced with the increase of Ti content, and ranges from 215HV0.2 to 585HV0.2, which is about 3 to 7 times that of the substrate. The strengthening mechanism of Ti0.2CrFeCoNiCu is solid solution strengthening, and when the Ti content is greater than 2, the strengthening mechanism of TixCrFeCoNiCu coating is precipitation strengthening. The influence of Ti on the wear resistance exhibits the same trend as with hardness. When Ti increased from 0 to 0.8, the wear rate of the TixCrFeCoNiCu coating changed from

2.26
×

10

−
4

mm

3

Nm

−
1

to

9.92
×

10

−
7

mm

3

Nm

−
1

:

smaller than the substrate. The addition of Ti increases the current corrosion density of TixCrFeCoNiCu coating, but both coatings still exhibits superior corrosion resistance relative to the substrate.