bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low density polyethylene/poly(butylene adipate-co-terephthalate) films: Effect of a compatibilizer on morphology and properties
Authors: Hemsri S , Puttiwanit K , Saeaung K , Satung P 
Published: December 2020

Abstract
Low density polyethylene (LDPE)/poly(butylene)adipate-co-terephthalate (PBAT) blend films were fabricated using a cast film extruder with different content of PBAT (0,10, 20 and 30 wt%). Polyethylene-graft-maleic anhydride (PE-g-MA) was used as a compatibilizer for the LDPE/PBAT blends. Morphology, mechanical properties, thermal properties, water vapour and oxygen permeability properties of the LDPE/PBAT films with and without adding the compatibilizer were investigated. Scanning electron microscopic (SEM) results revealed that the LDPE/PBAT/PE-g-MA films showed better compatibility and homogeneity between LDPE matrix and PBAT phase. Young’s modulus and tensile strength of the LDPE/PBAT/PE-g-MA films were higher than those of the LDPE/PBAT films. The PBAT content and incorporating PE-g-MA did not affect on melting temperature (Tm) of the LDPE/PBAT blends. On the other hand, melting enthalpies (ΔHm) of the polymer blends decrease as increase in PBAT concentration and at same content of the PBAT, the melting enthalpies (ΔHm) of the LDPE/PBAT/PE-g-MA films were higher than those of LDPE/PBAT films. Water vapor transmission rate (WVTR) of the blend films increased but oxygen permeability (OP) decreased when the PBAT content increased. Compared with uncompatibilized LDPE/PBAT films at the same PBAT loading, the compatibilized LDPE/PBAT films provided a lower water vapor barrier whereas the LDPE/PBAT/PE-g-MA films showed a better oxygen barrier.
A Wideband Printed Monopole Antenna with a Co-Planar Waveguide Feeding
Authors: Surin Chanapon , Srimoon Duangarthit , Mearnchu Jhirat 
Published: December 2020

Abstract
A wideband printed monopole antenna with a co-planar waveguide feeding is presented. This antenna provides a frequency range of 1.7 – 6.0 GHz. It is a flat conductor on FR4 printed circuit board. The shape of ground and pole are rectangle that the 2 corners near the feeding point are 25 degree chamfered, symmetrically. The ground is etched to form a co-planar waveguide for feeding. For this work, the antenna is simulated by using computer program before fabricating a prototype. The antenna provides an omni-directional radiation same as donut shape at the low frequency of the operating band. The radiation pattern is change when the frequency is shift to high but still omni-direction. The bandwidth of the antenna is 112% between 1.7 GHz and 6.0 GHz with the reflection coefficient less than -10 dB across the band. Gains of the antenna are 2.3, 4.9, and 3.4 dBi at the frequencies of 1.8, 3.8, and 5.8 GHz, respectively. They are the 3 points of low-, central- and high-frequency of the operating band. The size of the antenna is 70.0 × 40.0 mm2. Advantages of the antenna are wideband, low profile structure, light weight, and can be fabricated by FR4 make it low-cost.
Kinetics studies and thermodynamics of oil extraction from immobilized microalgae cells of Chlorella vulgaris: The effect of the different matrix system
Authors: Ramesh N , Mat Yasin N H , Mohd Arshad Z I 
Published: December 2020

Abstract
This research article discusses the effect of different chemical matrices used for the immobilization of microalgae cells of Chlorella vulgaris on oil extraction in terms of oil yield, kinetic values, and thermodynamic values. The experimental procedures began with microalgae cultivation, immobilization of microalgae, microalgae harvesting, and oil extraction. For the immobilization method, the matrix systems involved were sodium alginate (SA), calcium alginate (CA), and sodium carboxymethyl cellulose (CMC). For the oil extraction process, heptane was used as an only solvent at different temperature and extraction time. The amount of oil extracted from the SA system was found to be the highest compared to other chemical matrix systems, which is 25.11 % at 348 K. The values of the reaction rate constants were found to increase with temperature and extraction time for SA and the activation energy was determined to be 39.6636 kJ/mol, which is lowest among the systems. Moreover, with the enthalpy value of 0.115 kJ/mol, the extraction process using the SA system is endothermic and was found to be industrially more feasible process compared to other matrix systems. Hence, the results proved that the immobilization of microalgae for biodiesel production is considerable for the future biofuel industry.
Extraction of pectin from banana (Musa acuminata x balbisiana) peel waste flour using crude enzymes secreted by Aspergillus niger
Authors: Kumoro A C , Mariana S , Maurice T H , Hidayat J P , Ratnawati R , Retnowati D S 
Published: December 2020

Abstract
Intensive cultivation has maintained annual banana production in Indonesia at about 7 million tons since 2015. Banana fruits bear about 35 - 40% weight of peel waste, which contains 20.28 g pectin/100 g the dry matter. The peel waste may trigger serious environmental problems. This study aimed to investigate the effect of substrate concentrations and time on the pectin yield extraction from banana peel waste flour using crude pectinase secreted by Aspergillus niger. Crude pectinases were prepared through batch fermentation of banana peel flour using A. niger. The enzymes were used to hydrolyze banana peel waste flour at various substrate concentrations and time at 323 K. The results indicate that the increase of both extraction parameters leads to increase the pectin yield to some extent and then level off. However, further increase of both extraction parameters cause inhibition by galacturonic acid. The highest pectin yield (10.8% weight) was achieved at 323 K and 0.067g/mL substrate concentration for 120 minutes. Applications of this result are expected to increase the economic value of banana peel waste. However, further study in the effect of other extraction parameters such as temperature, enzyme loading, pH, flour size and pectin purification are required.
Immunological properties of the chicken egg yolk (IgY) antibodies against Vietnamese cobra Naja Naja venom
Authors: Nguyen V T , Vu T T H , Hoang V T , Nguyen T V , Lam T D , Nguyen K C , Than V T , Le V P 
Published: December 2020

Abstract
Venomous snake bite is common poisonous accident and important medical problem around the world. The snake anti-venom is only type-specific protection to each venom type that was used to immunize. In this study, the chicken egg yolk (IgY) antibodies against the Vietnamese cobra Naja Naja venom was developed and evaluated in in-vitro (ELISA and SDS-PAGE) and in-vivo (hen and mice immunization). In particularly, the LD50 of the Vietnamese cobra Naja Naja venom was determined at 1.46 g kg−1 body weight of the Swiss mice. The ISA Brown layers of 16 to 18-week-old were immunized intramuscularly with the Vietnamese cobra Naja Naja venom at 0.5 mg kg−1 body weight of the layers. The specific anti-venom antibodies were presented in both serum and egg yolk at 14 days, reached to highest antibody titer at 49 to 56 days and lasted up to 111 days post-immunization. The IgY antibodies purified from the egg yolk revealed potential neutralization and protection of Vero cells and Swiss mice from toxicity of the Vietnamese cobra Naja Naja venom. To the best of our knowledge, this study result is the first cobra snake anti-venom developed in laying hens against the Vietnamese cobra Naja Naja venom. Further study is needed to whether this specific IgY anti-venom antibodies can be used as an antibody therapy for treatment of venomous snake bites in the future.
Evaluation of polyphenol content and antioxidant activities of Dill leaves extract Anethum graveolens L.
Authors: Nguyen V T , Nguyen N Q , An T N T , Van N T , Anh N H T 
Published: December 2020

Abstract
Natural plants are an excellent source of materials for the extraction and application of bioactive compounds. Two extracts from the Dill leaves (Anethum graveolens L.), including the ethanol leaves extract (ELE) and the extract of the aqueous leaves (ALE), were applied to determine the polyphenol, flavonoid content and antioxidant activity of this plant. This plant preliminary phytochemical screening was found to have positive reactions for alkaloids, flavonoids, triterpenoids, saponins, tannins, coumarins and reducing assays. The findings of the quantitative determination revealed that the TPC of ELE and ALE was 69.76 ± 1.57 and 47.71 ± 1.44 mgGAE/g dry extract, respectively. In contrast, TFC was 49.10 ± 1.30 and 19.39 ± 0.61 mgQE/g dry extract, respectively. ELE exhibited the highest DPPH (IC50 = 149.39 ± 5.74 µg/ml) and ABTS (IC50 = 87.43 ± 3.07 µg/ml) radical scavenging activity. These results show that Dill can be used in culinary applications with the ability to minimize oxidative stress.
Effects of microwave extraction conditions on polyphenol content and antioxidant activity of pomelo extract (Citrus maxima (Burm.)Merr.)
Authors: Nguyen N H K , Duong H N , Long H , Nhi T T Y , Phat D T 
Published: December 2020

Abstract
The albedo, white peel of pomelo Citrus maxima (Burm.)Merr., is by-product of food processing, and has polyphenol and antioxidant activity. However, there are not many studies on polyphenol from pomelo peel in Vietnam by microwave extraction. Microwave-assisted extraction helps more efficient heating, faster energy transfer, increasing or decreasing temperature control, saving solvent and cost to extract active ingredients from plant materials. This research applied microwave extraction to extract polyphenol from pomelo Citrus maxima (Burm.)Merr. The factors that affected the extraction process such as solvent concentration, microwave power, extraction time and material to solid ratio were investigated. The results obtained that the highest polyphenol content (2.46 gGAE/L) and antioxidant activity (1325.85 µmolTE/L) with ethanol concentration of 60%, microwave power of 300W, microwave-assisted time of 2 minutes, and material to solvent ratio of 1:30.
Optimization of Culture Conditions on the Proliferation of Aspergillus Terreus N-GL1 Strain Isolated from Curcuma Longa L. by Design-Expert 6.0.6 and BC Pharsoft Software
Authors: Vo T N M , Nguyen D N , Nguyen V T 
Published: December 2020

Abstract

Curcuma longa L. is widely used as spices and medicines. Leaves, stems and rhizomes of the plant contain essential oils and provide a useful habitat for different endophytic fungi groups. Strain of Aspergillus terreus was isolated from Curcuma longa L. and was determined to be capable of producing secondary metabolites against bacteria by disc diffusion method and optimization of culture conditions by Design-Expert 6.0.6 and BC Pharsoft software. This research identified of the culture conditions for A. terreus N-GL1 strain produced secondary metabolites against Staphylococcus aureus and MRSA (Methicillin resistant Staphylococcus aureus) good: appropriate carbon source was saccharose 1% or molasses 2,2%; suitable nitrogen sources are potatoes 10% at pH 7; initial amount of yeast cells was 104 CFU/ml; incubated at room temperature for seven day. This study was found out as suitable conditions for A. terreus N-GL1 strain produced the secondary metabolites against S. aureus and MRSA.
Effects of Vacuum Concentration on Color, Polyphenol and Flavonoid Contents and Antioxidant Activity of Pomelo Citrus maxima (Burm. f.) Merr. Juice
Authors: Nhi T T Y , Phat D T , Quyen N N , Cang M H , Truc T T , Bach L G , Muoi N V 
Published: December 2020

Abstract
Pomelo (Citrus maxima (Burm. f.) Merr). juice is known as an enriched source of antioxidants and nutrients. It is therefore necessary to develop a preservation method for freshly prepared juice. This study aims to determine the effect of the vacuum concentration process on the change in color, bioactive compounds and antioxidant activity of pomelo juice. High pressure showed negligible effects on color. However, longer heating time seemed to cause browning in juice. In comparison with the fresh sample, total color difference (TCD) value of the treated sample was 6.73 ± 0.58 after 150 min of heating at 85°C. The total polyphenol content (TPC) values in the sample also increased with longer heating time or increased pressure. The total flavonoid content (TFC) seemed to be non-responsive to changes in heating time and pressure but was closely related to total soluble solid. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) of pomelo juice are affected by heat and, to a lesser extent, by pressure. The changes caused by the application of vacuum dehydration in the juice texture resulted in a higher water loss and higher sugar content (52.92 ± 0.79 °Brix).
Performance and cost analysis of hydrogen production from steam reforming and dehydrogenation of ethanol
Authors: Khamhaeng P , Kim-Lohsoontorn P 
Published: December 2020

Abstract
Mitigation of carbon dioxide (CO2) emission has been a worldwide concern. Decreasing CO2 emission by converting it into higher value products such as methanol can be a promising way. However, hydrogen (H2) cost and availability are one of key barriers to CO2 conversion. Ethanol can be a sustainable source for H2 due to its renewable nature and easy conversion to H2-rich gas mixtures through ethanol steam reforming process. Nevertheless, steam reforming of ethanol generates CO2. Hence, this research is focused on different methods of H2 productions about a 1,665.47 t/y from ethanol for supplying to methanol plants was performed using Aspen PLUS V10. The ethanol steam reforming process required the lowest required ethanol feed for a certain amount of H2. In contrast, the ethanol steam reforming process presented significant amount of CO2 emission from reaction and electricity consumption. But the ethanol dehydrogenation of ethanol not only generates H2 without CO2 emission from the reaction but also ethyl acetate or acetaldehyde, which are value chemicals. However, ethanol dehydrogenation processes in case II and III presented relatively higher cost because by-products (ethyl acetate or acetaldehyde) were rather difficult to be separated.
Latest trends in Syngas production employing compound catalysts for methane dry reforming
Authors: Yusuf M , Farooqi A S , Keong L K , Hellgardt K , Abdullah B 
Published: December 2020

Abstract
The rise in the global population has ultimately steered to increase in global energy consumptions. This masqueraded several challenges worldwide. The most troublesome being the accumulation of greenhouse gases (GHGs) that induced a global climatic change. The utilization of fossil fuels like petroleum, coal and natural gas on the copious scale has led to the elevated levels of carbon dioxide (CO2) and methane (CH4) in the global environment. Dry reforming of methane (DRM) is a highly favorable technique as it utilizes two of the prominent GHGs, CH4 and CO2 to generate a useful and valuable product viz. syngas. However, the deactivation, coking and sintering of catalysts are still the main hurdles in the commercialization of the process. The compound metal catalysts have shown enhanced activity and prolonged durability when compared with monometallic catalysts due to enhanced morphology, improved and stable catalytic structure, i.e., both coke and sintering resistant at high temperatures. This brief review spotlights the recent developments in DRM by emphasizing parameters such as the effects of catalyst support, bimetallic catalyst, promoters and strong metal-support interaction (SMSI) in the last decade.
Thermochemical characterization of invasive Axonopus compressus grass as a renewable energy source
Authors: Reza M S , Afroze S , Azad A K , Sukri R S , Shams S , Taweekun J , Saghir M , Phusunti N , Abu Bakar M S 
Published: December 2020

Abstract
The necessity of energy is increasing massively, whereas fossil fuel resources are diminishing with time, and produce greenhouse gasses while burning. To resolve these issues, lignocellulosic biomass such as Axonopus compressus that is available in Brunei Darussalam have been investigated. For characterization analysis, dried 0.25 mm samples were utilized. The moisture content (4.56%), volatile matter (72.04%), fixed carbon (17.11%), and ash contents (6.29%) of the sample were achieved from the proximate analysis result. The HHV (Higher heating value) of 17.96 MJ/kg and the moisture content value is an indication of a reasonable source for biofuel production. The ultimate analysis showed the carbon (C), hydrogen (H), nitrogen (N), sulfur (S), and oxygen (O) contents were 43.46%, 5.68%, 1.45%, 0.13%, and 49.10%, respectively. From the thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) results, the highest decomposition rate was found to be 6.03 wt. %/min at 334 °C temperature in pyrolysis and 30.63 wt. %/min at 443 °C temperature in combustion condition.
Characterization of Stearic Acid and Paraffin Incorporated with Aluminium as Filer for the Development of Phase Change Material Composite in Thermal Energy Storage
Authors: Abidin S Z , Ghani S A A , Osarieme UO , Jamari S S 
Published: December 2020

Abstract
With the increasing energy demand, shortage of energy has drawn attention towards the utilization of non-renewable energy sources. The development of thermal energy storage (TES) to fulfil the energy demand that has increased progressively over time is of great interest. TES systems are widely employed industrially especially for phase change materials (PCM) used in many fields with several applications. This study aims to synthesize, characterize and study the physicochemical and thermal properties of stearic acid and paraffin incorporated with aluminium as filler for the development of PCM composite. The PCM composites were prepared using 80wt% for the Al/SA and 80wt% Al/paraffin, respectively. The PCM composites were characterized using thermal gravimetric analysis, differential scanning calorimetry and scanning electron microscopy. Results showed good compatibility in physicochemical properties between stearic acid (SA), paraffin and aluminium (Al), respectively. It was observed that the thermal stability studied using thermal gravimetric analysis revealed slightly better stability exhibited by the paraffin PCM composite. This was as a result of the steeper slope exhibited by the stearic acid TGA curve as against that of the paraffin curve. Also, density analysis has resulted in an increment for both composite materials whereas; aluminium incorporated in paraffin composite has shown higher increment of density as compared with stearic acid composite. Therefore, PCM composite made from paraffin will be more effective as a TES material when used industrially as compared to the stearic acid PCM composite.
Synthesis of high-porosity hybrid geopolymer/alginate adsorbent for effective removal of methylene blue and optimization of parameters using RSM
Authors: Nurddin S M A S M , Sufian S , Man Z , Rabat N E , Ahmad N 
Published: December 2020

Abstract
In this work, high-porosity geopolymer/sodium alginate (GSA) adsorbent was successfully prepared by entrapping fly ash-based geopolymer into sodium alginate (SA) using a simple method. The geopolymer slurry was firstly prepared which involved the utilization of sodium hydroxide (NaOH) as the alkaline activator followed by the addition of SA and albumen into the slurry. Natural albumen was used as the foaming agent. The effect of mass ratio of geopolymer to SA, albumen content (wt%), NaOH concentration and curing temperature (°C) on the removal of methylene blue (MB) was investigated using one factor at time (OFAT) method and optimized by response surface methodology (RSM), which achieved by 30 run of experiments using central composite design (CCD). A quadratic model was employed to correlate all the independent variables for maximizing the MB removal through the analysis of variances (ANOVA). The model suggested that the optimum condition for the preparation of GSA adsorbent for the efficient MB removal of 84.94% was achieved with mass ratio of geopolymer to SA was 1:0.13, albumen content of 25 wt%, NaOH concentration of 7 M and curing temperature of 60 °C. The albumen content was the most effective factor in the preparation of GSA adsorbent that increased the MB removal, followed by the curing temperature and mass ratio of geopolymer to SA.
Anaerobic co-digestion for oily-biological sludge with sugarcane bagasse for biogas production under mesophilic condition
Authors: Ghaleb A A S , Kutty S R M , Ho Y C , Jagaba A H , Noor A , Al-Sabaeei A M , Kumar V , Saeed A A H 
Published: December 2020

Abstract
The oily-biological sludge is one of the toxic organic sludge generated from petroleum oil refineries wastewater treatment plants. However, its low Carbon/Nitrogen ratio (C/N) need a co-substrate material to meet the requirement of anaerobic digestion process C/N. The oily-biological sludge can act as a substrate and inoculum at the same time. Sugarcane bagasse is an organic waste and has high C/N ratio. Therefore, it is a proper material which can balance the batch C/N ratio. In this study, three mixing ratios for both materials with C/N ratios 20.0, 25.10 and 30.0 respectively. The temperature, mixing and digestion duration were 37 °C, 60 rpm and 33 days respectively. Both materials were pre-treated under thermo-chemical conditions to increase biogas yeild. The maximum biogas yield was for the maximum C/N and co-substrate/inoculum ratios with 9,268 mL.
Study on organic pollution treatment from Van Thanh canal water by vetiver grass model on gravel and sand in water circulation conditions
Authors: Giang L V , Le D A , Tuong L Q , Tan L V , Tran T 
Published: December 2020

Abstract
Most canals in Ho Chi Minh City receive urban wastewater which was led by underground sewers in the untreated cities and causes serious environmental pollution. The main objective of this paper was to investigate the effects of application models of vetiver grass in purifying wastewater in Van Thanh canal water. This model combined many vetiver grass and materials like sand, gravel, and stone to remove pollutants based on sedimentation, filtration, accumulation, and decomposition mechanisms of microorganisms that allow water to flow through the substrate, the system provides good transport of oxygen into the substrate, facilitating nitrification. The research was conducted under hydroponic conditions in three treatments (Treatment1: Gravel treatment, Treatment 2: Sand treatment, and Treatment 3: Combination material (Gravel& Sand). Each treatment was designed (n=2), with dimensions of 0.66 m x 0.46 m x 0.21 m (length, width, height), a layer of material with a thickness of 80 mm. Results showed that the average processing efficiency in the modes was PO43- 91.34%, NH4+ 96.67%, COD above 80% reaching QCVN 08: 2015/BTNMT, Vetiver had a very high capacity to purify wastewater. Result also illustrated that vetiver grass had a very high capacity to purify wastewater in Treatment 3 called the combination material of Gravel& Sand. Applying the CW CSFS system using Vetiver grass was proved for the needs of surface water treatment in Van Thanh canal water with restoring the ability of natural cleaning and restoring greenery in the whereas.