bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laboratory investigation on warm mix asphalt incorporating organo-silane additive
Authors: Omranian S R , Hamzah M O , Mounik G S , Reddy K P , Kapadia Y M , Teh S Y 
Published: April 2020

Abstract
Warm mix asphalt (WMA) was developed to reduce asphalt production temperatures and energy consumption. Production of toxic gas emissions can be reduced considerably. However, lowered production temperature results in the presence of trapped moisture in the aggregates that could lead to stripping and subsequently moisture susceptibility problems, and which can be mitigated by using additives. Asphalt mixtures incorporating such additive must exhibit at least similar performance to conventional hot mix asphalts (HMA) which produce at higher temperatures. This paper evaluates the engineering properties and moisture susceptibility of asphalt mixtures incorporating Organo-Silane additive for use as WMA and anti-stripping agent. WMA samples were compacted at 125 °C and 115 °C and their performance were compared with control HMA specimens. The asphalt mixtures were prepared using similar aggregate gradation and binder types. Mixture workability was quantified in terms of the Compaction Energy Index (CEI) that was measured by integrating the area under the densification curve between gyration 8 and 92% theoretical maximum density. Lower CEI implies a more workable mixture. The CEI of WMA was 76.4, which was much less than the corresponding value for HMA. Samples were also tested for Marshal stability, resilient modulus and wheel tracking (WTT) tests according to ASTM D6927, ASTM D4123 and BS EN12697-22 procedures, respectively. The control samples perform better in the stability test. The resilient modulus of WMA was only about 10% lower compared to HMA. Resistance to permanent deformation was measured from the dynamic stability (DS) or the number of wheel passes per 1 mm rut depth over the last 15 minutes in a 60-minute tracking test. The DS of HMA, WMA compacted at 125 °C and 115 °C were 3138, 3044 and 2837, respectively. From the rutting resistance standpoint, the results are not significantly different. Hence, incorporation of the additive does not adversely affect mixture rutting resistance despite the lowered production temperature.
Efficiency of zinc ions (II) adsorption using activated carbon from palm kernel shell
Authors: Jitjamnong J , Luengnaruemitchai A , Kongrit N , Kasetsomboon N , Khantikulanon N 
Published: April 2020

Abstract
The adsorption of wastewater from various industrial sources is important and one of the dangerous challenges the environment. This study focuses on the investigation of the efficiency of zinc ions adsorption by using activated carbon in synthetic wastewater. Activated carbon was prepared from palm kernel shells that were obtained from Songkhla province, Thailand. Activated carbon was prepared from palm kernel shells containing sodium chloride as a catalyst at the ratio 1:0, 1:1 and 1:2 (w/w), respectively. Activated carbon was calcined at 700 °C for 2 h. Next, it was washed with hot distillate water until pH = 7. After that, it was dried at 105 °C for 24 h. Iodine number was analyzed by using CHNS/O analyzer. The concentration of solution was examined by using atomic absorption spectrophotometer (AAS). The prepared activated carbon was characterized by thermogravimetric analysis (TGA), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), X-ray fluorescence spectrophotometer (XRF), X-ray diffractometry (XRD) and Fourier-transform infrared spectroscopy (FTIR). For the pure activated carbon, it was noteworthy that the major components were O (37.25%), N (30.95%) and C (26.54%), whilst a minor content was H (2.23%), C (1.73%) and Si (0.76%). This result was strongly consistent with the XRF analysis. The ratio of activated carbon to sodium chloride 1:2 (w/w) exhibited the highest iodine number (180.95±10.82 mg/g). The factors of adsorption including initial concentration (20-150 ppm) and adsorption time (2-10 h.) The result showed that the optimum conditions of adsorption containing concentration were 65 ppm and adsorption time was 10 h. The efficiency of adsorption was 69.73 %.
Treatment of laundry wastewater using chemically treated sugarcane bagasse
Authors: Ayu Haslija A.B , Abdulrazzak Rabee 
Published: April 2020

Abstract
Laundry wastewater constitutes of detergent compounds, bleaching agent, textile color pigments and dirt. These compounds are hazardous once discharged into the water source without proper treatment due to the adverse effects on the aquatic life in the freshwater bodies. This fixed-bed column adsorption study using the natural biomass from chemically treated sugarcane bagasse is proven to be effective for the removal of constituents present in the laundry wastewater. The synthetic laundry wastewater was prepared in the laboratory from a powder type of detergent with a concentration of 50mg/L and 250mg/L to be further used in the adsorption process. The characteristics of the synthetic laundry wastewater were analyzed by the turbidity, pH, dissolved oxygen (DO) and chemical oxygen demand (COD). The fixed-bed column experiment with the treated sugarcane bagasse was conducted under different parameters such as the effect of pH, initial concentration and bed height. The best removal efficiency was observed at a bed height of 10 cm with a concentration of 50 mg/L is 65%, followed by 33% and 20% for bed heights of 4 and 2 cm respectively. As for the concentration of 250 mg/L, the best removal efficiency was at a bed height of 10 cm which was found to be 58% followed by 26% and 17% removal for a bed height of 4 cm and 2 cm respectively. The kinetics of the adsorption was investigated using the kinetic models of Thomas and Yoon-Nelson. The experimental results fitted well on the Thomas model and Yoon-Nelson which showed a high linear regression value greater than 0.9. These results prove that chemically treated sugarcane bagasse is an effective low-cost adsorbent for reducing turbidity, pH, COD and increasing the DO concentration.
Engineering properties of ancient masonry materials in Thailand and substitution materials for historical structures preservation
Authors: Mahasuwanchai Peerasit , Wonganan Natthanan , Athisakul Chainarong , Tangchirapat Weerachart , Sahamitmongkol Raktipong , Leelataviwat Sutat 
Published: April 2020

Abstract
This paper presents the engineering properties of ancient masonry materials and substitution materials for the preservation of Thai historical structures. The study was divided into 2 parts. For the first part, the ancient masonry materials including brick and mortar were collected from various historical sites in Bangkok and Ayutthaya provinces. The engineering properties of masonry materials were evaluated in laboratory such as compressive strength, density, chemical compositions, porosity, and water absorption. The second part was investigation to find the suitable substitution materials for historical repair mortars. Fly ash was used as a pozzolanic materials to partial replace slaked lime for making historical repair mortar. The engineering properties of historical repair mortar containing were also evaluated and compared with the ancient masonry materials obtained from the first part. The binder to sand ratio was controlled at 1:3 by weight. The slaked lime was substituted by fly ash in the ranges of 10-30% by weight. The experimental results showed that the use fly ash to a partial replace slaked lime could decrease the setting time of historical repair mortar. The compressive strength of historical repair mortars with fly ash were ranged from 1.54-2.22 MPa, depending on the level of replacement, while that of the ancient masonry materials had the compressive strength of 1.88-2.71 MPa.
Synthesis and characterization of reduced graphene oxide-iron oxide nanocomposite as a potential fuel cell electrocatalyst
Authors: Yusoff F. , Suresh K. , Noorashikin M. S. 
Published: April 2020

AbstractDriven by the high demand for commercialization of fuel cell (FC) technology, a design of potential oxygen reduction reaction electrocatalayst based on reduced graphene oxide (rGO) and iron oxide (Fe3O4) nanocomposite has been described and denoted as rGO/Fe3O4.The nanocomposite was synthesized by means of facile one-pot process. The resultant rGO/Fe3O4was physically and electrochemically characterized by using Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffractrogram (XRD), Scanning Electron Microscopy (SEM), Cyclic Voltammetry, (CV) and Electrochemical Impedance Spectroscopy (EIS). The FTIR analysis shows the formation of rGO/Fe3O4from the presence of C=C, C-C and Fe-O bonds in the spectrum of the indicating the synthesis material is successfully obtained. XRD analysis also confirms the presence of rGO and Fe3O4in the composite by hematite structure indexed peak of diffractogram. Scanning Electron Microscopy (SEM) image depicts the attachments Fe3O4onto the surfaces of rGO. The composite was then dissolved in the solvent and drop-casted on the glassy carbon electrode (GCE) for electrochemical analysis. Cyclic Voltammetry (CV) shows increment in current responses of nearly two and half folds for rGO/Fe3O4/GCE compared to bare GCE. Electrochemical Impedance Spectroscopy (EIS) shows a stable electron transfers process with lower charge transfer resistance (Rct) of the nanocomposite modified electrode which due to the synergistic effect between rGO and Fe3O4.The results of the analysis show the compound could be a promising candidate as an electrocatalyst for fuel cell.
Integrated algal biorefinery and palm oil milling for bioenergy, biomaterials and biopharmaceuticals
Authors: Abdullah M A , Hussein H A 
Published: April 2020

Abstract
The call for greener processes and eco-friendly products has been the essence of the 2030’s core agenda on 17 Sustainable Development Goals. The major challenge is in bringing systems thinking and holistic worldview to the planning and strategies to develop the Economics whilst incorporating the Environment, and Socio-cultural diversity dimension as equal components. This means a total revamp of human activities such that the discussion on climate change, famine and poverty, destruction of eco-systems and habitat for wildlife, and the emerging infectious diseases, is as relevant as, if not more important than, discussing about artificial intelligence, robotics, flying and driver-less vehicles, and exploration to Mars. There is an urgent need for resource optimization, better biodiversity management and improved agro-practices for food production and distribution, affordable health care, and cleaner energy, air and water, with strict monitoring, regulation and enforcement to minimize emission, pollution and wastage. The focus of this presentation is to highlight research and development efforts towards the realization of sustainable bioenergy production, environmental remediation and conversion into biomaterials via integrated algal biorefinery and palm oil milling processes. Recent development in microalgal research with nanotechnology for biopharmaceuticals and anti-cancer products will be discussed. The image problem and the negative perception surrounding oil palm industries especially with regards to the impact on the environment, and the efforts towards a more sustainable production route will be highlighted. This hopefully could bring forth insights towards partnerships and collaboration among the industrialists, investors, economists, scientists, engineers, and social scientists to tackle the immediate and pressing problems facing the Planet and the People, whilst reaping the Profit, yesterday, today and tomorrow.
Hydrogen adsorption on calcium-decorated planar aluminene using density functional theory
Authors: Bayasen D S , Villagracia A R , Pedrosa G R , Lin H , Ong H L , David M , Arboleda N 
Published: April 2020

Abstract
With the rising demand for clean energy, the concept of hydrogen economy has grown more popular, and with this popularity the need for better hydrogen storage materials increases. Decorated surface materials such as planar hexagonal aluminene are being studied to determine their potential as good hydrogen storage materials. This study theoretically investigates hydrogen adsorption on aluminene decorated with calcium, where calcium is binded on the top, bridge and hollow sites of aluminene using density functional theory. Results on decoration adsorption have shown that calcium can easily bind a distance of 1.80 Å to 2.80 Å on the top, bridge and hollow sites with binding energies of 1.85 eV, 2.01 eV, and 3.32 eV, respectively. The density of states of the calcium-decorated surface show that its electronic property is generally maintained with zero magnetization. Small amount of charges were adsorbed from the aluminium atoms to the calcium atom based on the charge difference. This leads to hydrogen molecule adsorption with low adsorption energies ranging from 34.13 meV to 80.51 meV. In addition, minimal broadening of energy levels were shown by the density of states. With these results, it can be concluded that planar hexagonal aluminene with low concentration of calcium atoms may lower the hydrogen capacity of aluminene.
Self-made electromagnetic vibration energy harvester of different stroke length and number of coil turns
Authors: Bin Jamsari Shahrul Azhar , Quen Lee Kee , Kang Hooi-Siang , Tey Wah Yen , Lee Kiat Moon , Tan Lit-Ken 
Published: April 2020

Abstract
This paper presents the experimental work on a new tube-shape electromagnetic vibration energy harvester to obtain its optimum peak-to-peak voltage output based on different stroke length, number of coil turns and optimum frequency. The harvester is fabricated using Acrylonitrile Butadiene Styrene (ABS) material. It consists of housings with three different stroke lengths, top and bottom covers, Neodymium Iron Boron (NdFeB) magnets, spring and copper coil. The tested stroke lengths are 40 mm, 45 mm and 50 mm while the number of coil turns are 10, 20 and 30. A standard energy harvesting circuit which consists of full-wave bridge rectifier and a capacitor is designed and fabricated to conduct this experiment. The importance of this circuit is to convert alternating current (AC) to direct current (DC) as well as to enable harvesting and storing processes of electrical energy. The harvester is tested on external vertical vibrations generated by shaker with frequency ranged from 5 Hz to 50 Hz with interval of 5 Hz. The raw voltage readings have been extracted from Oscilloscope and are analysed using Microsoft Excel and Octave software. From the results obtained, the optimum peak-to-peak voltage harvested is 39.41 mV at resonant frequency of 5 Hz by 50 mm stroke length and 30 coil turns device. The higher the stroke length and number of coil turns, the higher the peak-to-peak voltage can be harvested.
Microscale structure designing of nanoparticle-based photocatalyst films for enhanced functionalities and efficient energy utilization
Authors: Kameya Yuki , Yabe Hiroki 
Published: April 2020

AbstractPhotocatalysts have increasingly become important materials to utilize renewable solar energy for decomposing pollutants, producing clean water, achieving self-cleaning surface, and so on. Therefore, it is desirable to expand the applications of photocatalysts by enhancing the functionalities and allowing ample design flexibility. Here the potential of nanoparticle-based photocatalyst films with microscale surface structures was investigated in order to enhance their useful functionalities. Photocatalyst films with microscale surface structures were prepared using the suspension of titanium dioxide (TiO2) nanoparticles. The micro-scale structural features of prepared films were evaluated using a scanning electron microscope. Also, an atomic force microscope (AFM) was used. The AFM analysis of a film consisting of nanoparticle spherical aggregates revealed a surface profile of subwavelength surface structure. Then the optical and wetting characteristics were investigated. It was found that the visible-light transmittance increased due to subwavelength surface structures and that the microstructured TiO2films exhibited the contact angles below 10 degrees, i.e., superhydrophilic behavior, without ultraviolet-light illumination. On the basis of the presented results, it was suggested that the microscale surface structures of photocatalyst film can be designed to achieve enhanced functionalities. It is expected to effectively utilize the energy of sunlight in many applications using functional photocatalyst films with optimized design.
Production of high quality empty fruit bunch pellet by water washing and torrefaction
Authors: Krerkkaiwan Supachita , Boonbumrung Duangkamol 
Published: April 2020

Abstract
EFB pellet is the high potential biomass for combustion process due to the relatively high heating value and the high availability in the Southern of Thailand. However, the containing of high unwanted minerals, especially K and Cl is the main drawback of EFB pellet which causing the ash fouling or/and slagging during the combustion. In this study, the high quality EFB pellets (low K, low Cl, high heating value) were produced by applying the water washing and torrefaction methods. For water washing treatment, the effect of water and acetic acid solution on the mineral content of EFB pellet was studied. In addition, the effect of torrefaction temperature (250, 280 and 300 °C) on the quality of EFB pellet was investigated. Results revealed that the ash content of the washed EFB decreased from 5.3 % to 3.0 % and 0.7 % by washing with tap water and acetic acid solution, respectively. Comparing with the raw EFB pellet, K and Cl in ash were significantly reduced by washing about 60 % and 88 %, respectively. Heating value of the EFB and washed EFB pellet were increased after torrefaction with the higher temperature. The water washed EFB pellet and torrefied at 300 °C gave the highest heating value about 24.3 MJ/kg. It was 33% increased HHV when comparing with raw EFB pellet.
Quality improvement of syngas from gasification process of palm kernel using NiO/CaO catalysts on ceramic supporter in coupled with biochar absorbent from agricultural residues
Authors: Rattanahirun S , Khamwichit A , Dechapanya W 
Published: April 2020

Abstract
In this study, palm kernel shells were utilized in the gasification process to produce syngas. In addition, biochar prepared from pyrolysis of the left-over mangosteen and durian peels were used in the gasification process to enhance the tar removal efficiency. The expected outcomes of this study could result in not only the generation of renewable energy from but also the waste utilization of agricultural residues. The effect of catalysts and biochar on the syngas quality improvement were particularly studied. Palm kernel shell was used as raw material. The compositions and heating values of the biomass were characterized by the proximate, ultimate, and bomb analyses, respectively. Syngas was produced from a downdraft gasifier connected with catalytic and adsorption units in sequence. The gasification process was operated with 1 kg of palm shell per batch at a fixed air flow rate of 25 L/min. The NiO/CaO (10 %wt) catalysts on ceramic supporter with various NiO contents of 2%, 4%, and 8% were synthesized by co-impregnation. Biochars were synthesized by pyrolysis process of durian and mangosteen peels at around 300 - 500 °C for 2 hrs. Morphology and compositions of the synthesized catalysts and biochar were analyzed. The results of SEM analysis showed that the NiO and CaO were deposited and well dispersed on the porous ceramic ring supporters. The presence of active NiO on the catalyst was also confirmed in FTIR result with (wavelength of 692 cm−1). Biochar from durian and mangosteen peels, with BET surface area of 0.9219 - 0.9989 m2/g and adsorption pore size of 11.193 - 11.912 nm, were obtained from a pyrolysis process at 400 - 700 °C. The syngas samples were collected from the gasification unit every 15 min to 60 min. The gas chromatography was used to analyze the syngas compositions. The GC results indicated that increasing NiO contents in the catalysts tended to result in increasing CH4 composition of the syngas for both systems with and without biochar. With tar filtration unit containing biochar, the ability of tar removal was significantly increased by 2 to 9 times comparing to the system without biochar.
Effects of aquifers on soil temperature distribution around deep buried heat exchanger
Authors: Zhang Y P , Jia G S , Ma Z D , Xia Z H , Cao Y. , Jin L W 
Published: April 2020

Abstract
Deep buried heat exchanger has been increasingly applied into the building heat source through the utilization of geothermal energy. During the geothermal system design process, the aquifer is an important factor that affects the overall performance prediction. The flow of underground water at different positions changes the temperature distribution of the soils around the buried pipe and then influences the heat exchange at different depths. Consequently, the variation of the temperature field causes the thermal radius of the heat exchanger no longer regularly distributed, which affects the determination of the well spacing. With the aims of improving the accuracy of performance estimation, the aquifer effect is carried out by this study. The solution to the moving line source theory is used to acquire the temperature response at different positions. The overall effect of the underground water with different velocities on the performance is evaluated. The soil temperature distribution in the heat exchange zone with aquifers at different depths is studied in detail. The predicted thermal influence radius at different depths with various groundwater velocities and soil thermal properties showed that the temperature distribution around the buried heat exchanger is largely influenced by the groundwater movement. Under the simulation condition, the thermal radius increases from less than 10 m for pure conduction condition to a maximum value of 25.3 m with groundwater flow. The aquifer enhances the heat absorption of the heat exchanger, but the high flow rate also leads to a large thermal radius. The obtained thermal influence radius under different conditions can provide guidance for the design of the geothermal system.
An analytical model for vertical-butted geothermal well with different groundwater flow directions
Authors: Jia G S , Ma Z D , Jin L W , Zhang Y P , Cao Y , Meng X Z 
Published: April 2020

Abstract
Geothermal has become a popular renewable energy in recent decades due to its properties of non-polluting, clean and large reserves. The vertical-butted geothermal well is a new structure for geothermal utilization. Two vertical boreholes with a certain distance are connected at bottoms by directional drilling to form a U-shape circulation loop. Due to the existence of the aquifers, the movement of underground water extends the heat exchange range and affects the geothermal system performance. This paper aims to develop an analytical method to solve the soil temperature field around the vertical-butted geothermal well with different flow directions. Taking the interacted effect of the two parallel pipes on the surrounding soil into consideration, the temperature distribution in the heat exchange zone is obtained. It is found that the temperature field changes significantly when the groundwater flow exists. The movement of underground water extends the downstream thermal radii from 4.8 m to 10.7 m, 10.6 m and 11.7 m when the flow directions are 0°, 45° and 90° toward the axis of the two pipes, respectively. The upstream thermal radii reduce from 5.4 m to 1.9 m for all the cases with groundwater movement. In addition, the effect of the underground water flow direction on the temperature field around the butted wells is analyzed. The results show that when the groundwater flow direction is perpendicular to the axis of the two pipes, the temperature field is the most beneficial to the performance of the vertical-butted geothermal well.