Abstract: Consumptions of fermented vinegar made of fresh fruit juices have been increased dramatically due to their freshness, high vitamin content, and low caloric consumption. Unpasteurized fruit juice produced by pressing or squeezing of the fruits also have many diverse microflora which is normally present on the surface of fruits during harvest and postharvest processing and possibly include transport, storage, and processing. In the study, many microorganisms producing acid especially bacteria, fungi, and yeasts demonstrated the high acid production and using fruit juice as a substrate for their growth. Three acid producing bacteria were isolated and characterized for the acid production as well as applied for the fruit vinegar fermentation process.
Abstract: The distribution of residual pesticides in soil and rice grain was studied in rice farming area covered in Samchuk district, Suphanburi province, Thailand. The 19 samples of soil and rice grain were collected by random sampling in 2015 covered 7 sub-districts. The residual carbofuran and glyphosate in soil and rice grain was quantitative determined based on standard method. It was found that the concentration of carbofuran was found in the range of ND-0.0512 µg/kg and ND-0.0865 µg/kg for soil and rice grain, respectively. Glyphosate was found in the range of ND-0.2632 µg/kg and ND-0.2244 µg/kg for soil and rice grain, respectively. The residual levels of carbofuran and glyphosate in soil and rice grain depended on a spray period time, their decomposition and their concentration usage. The residual levels of carbofuran and glyphosate did not significantly quantitative correlation between soil and rice grain for this study area.
Abstract: The aim of this work was to study the potential of the agricultural waste byproduct as a low-cost adsorbent for removal of phosphate ion (PO43-) from synthetic wastewater. The simple preparation of carbonized filter cake (CFC) was performed at 550°C. CFC was also characterized using FTIR, X-ray fluorescence analysis. The adsorptive parameters of batch experiment, such as pH of solution, dosage and contact time were systematically studied in order to the optimization condition. The optimum conditions of pH, contact time and adsorbent dose were to be 6, 60 min, and 2 g/L, respectively. The Langmuir and Freundlich isotherms were used to calculate the adsorption parameters that was able to describe the equilibrium isotherm and adsorptive mechanism. The maximum monolayer adsorption capacity of CFC was estimated as 20.32 mg/g. The optimized condition was applied for phosphate removal from synthetic wastewater. The achieved phosphate removal efficiency from synthetic wastewater sample was to be 92.4%. Filter cake is a low-cost byproduct of sugar cane but it can also highly effective remove phosphate ion from aqueous solution. The modification of filter cake surface via chemical reaction as a new adsorbent in order to increase surface sites and high affinity with phosphate ion will also be further studied.
Abstract: This work was focused on evaluating the potential of bamboo powder modified with manganese oxide (MnO-BP) as a low-cost byproduct adsorbent for the adsorption of cadmium(II) ion. A batch method was carried out at room temperature and the optimized conditions. The optimization of adsorption parameters including pH, equilibrium time, dosage and initial Cd(II) concentration was also systematically studied for the removal of cadmium(II) ion. The maximum monolayer adsorption capacity of MnO-BP was estimated as 8.57 mg/g that it more adsorption capacity than untreated-bamboo powder by about 5 times. The Langmuir and the Freundlich isotherms were used to describe the adsorptive mechanism and calculated the maximum monolayer adsorption capacity. It was found that the data from MnO-BP fitted well to the Freundlich isotherm with R2>0.99. It indicated that the adsorptive behavior of MnO-BP to cadmium(II) ion is preferable. In this work, MnO-BP was used for the removal of cadmium(II) ion in wastewater sample. The MnO-BP is a low-cost adsorbent that can be used to remove cadmium(II) effectively.
Abstract: The aim of this work is to investigate phenol removal by immobilized peroxidase extracted from cauliflower stem. Peroxidase was partially purified by membrane filtration and diafiltration. Almost four-fold increase in the measured activity of partially purified peroxidase was obtained. The enzyme was then immobilized on to the surface of regenerated cellulose ultrafiltration membrane (molecular weight cut-off 30 kDa) using a dead-end filtration unit. Three different immobilization methods (physical adsorption, cross-linking and covalent-bonding using glutaraldehyde as a membrane activator) were tested. The immobilization and enzymatic reaction efficiency were evaluated in terms of the immobilization yield, the enzyme leakage from the system, the phenol removal and the permeate flux. Results showed that the immobilization methods did not much affect the permeate flux of the membrane. The peroxidase immobilization by covalent-bonding on regenerated cellulose membrane produced the highest immobilization yield and the lowest enzyme leakage. The immobilized enzymatic reaction efficiency on phenol removal was 100% at operational time 60 min and reduced to 96.4% at 600 min.
Abstract: The aim of this work needed to discover the problem of lacquer thinner products claimed with dissatisfying the quality of coating and color appearance. The trace metals produced cans was focused on release to solvents. The contaminated trace metals including Fe, Sn, Cu, and Zn in lacquer thinner were also determined by atomic absorption spectrometry (AAS). The lacquer thinner samples were simply carbonized to be ashes by furnace muffle at 550°C for 8 hours. The carbonized ashes were then also digested by conventional wet digestion with concentrated nitric acid until a clear solution was archived. Twenty samples of lacquer thinner were achieved from the paint manufacturer. The content of Fe, Sn, Cu, and Zn was found in the range of 0.0631-77.190 mg/kg, ND-12.613 mg/kg, ND-1.4679 mg/kg, and ND-0.4028 mg/kg, respectively. The result of high concentration of Fe related to the appearance of lacquer thinner color. The evidence of released heavy metals in the ashes of lacquer thinner samples was evaluated by X-ray fluorescence technique. The result of this work was concluded that the contaminated trace metals in the suspected lacquer thinner samples were leached from the metallic package.
Abstract: This work was to investigate the mechanical and physical properties of light weight block with addition of banana fiber. The formulation series of concrete block were divided into two groups: banana fiber for replacing cement and sand, respectively. Banana fibers were varied from 0.0 to 7.5 %wt. and were evaluated by compressive testing, density and water absorption and changing length at water immersion of 28 days. Optimum formulation of concrete adding banana fiber is ratio of sand: cement: lime: gypsum: aluminum powder: banana fibers: 50: 27.5: 9: 9: 2: 2.5, respectively. The increase of water absorption and changing length were found with increase of fiber content whereas the density decreased. However, the mechanical and physical properties of banana fiber/concrete block were subject to standard according to Thai Industrial Standard 1505-2541. From this study, it indicates that banana fiber can be used as an alternative precursor material for producing the light weight and cost effectiveness block.
Abstract: The gamma ray shielding properties of cement paste containing ilmenite and barite (BaSO4) at different concentration were investigated using beam transmission method for 59.5 keV gamma ray energy of 241Am radioactive isotopes by using NaI(Tl) scintillation detector. The mass attenuation coefficients (μm) of these shielding materials were calculated. It was found that the mass attenuation coefficients increase with increasing of ilmenite and barite content up to a value of 60% by weight. The highest value of μm was 0.425 ± 0.003 cm2/g for cement paste containing ilmenite and 1.598 ± 0.039 cm2/g for the cement paste containing barite. The mass attenuation coefficient values were compared between cement pasted containing ilmenite and barite. The result show that cement paste containing barite showed good gamma ray shielding performances than that for the cement paste containing ilmenite.
Abstract: This research aims to fabrication and evaluation the properties of cement reinforcement made from Panicum repens. The research is divided into two parts are as follows; to determined the optimal ratio selection, and to compare the properties of Panicum repens reinforced cement, and without grasses by using the optimal ratio. The raw materials used in this research were cut in length of 2.0-2.5 cm. In this research was determined the properties of Panicum repens reinforced cement in terms of bulk density, water absorption, and compressive strength. The influence of fibers soaked with 5% of sodium hydroxide concentration was also conducted in this research. The surface structure and chemical characteristics of fibers used to produce reinforced cement were observed by using scanning electron microscope (SEM), and energy dispersive x-ray spectrometer (EDS), respectively. Moreover, relationships of information collected from this research were concerned. Furthermore, the addition of Panicum repens fibers could improve the flexural strength of composite materials.
Abstract: Utilizing para wood ash can offer an alternative method of adding value to agricultural wastes and help to conserve the environment. The feasibility of using para rubber leaves as an environmentally friendly material for prototype lightweight flat sheet production was investigated. Properties of lightweight flat sheet made from different proportions of para rubber leaves mixed with para wood ash were compared with ordinary Portland cement (OPC). Morphology and element compositions of untreated and treated para rubber leaves with 20% NaOH solution were observed using a field emission scanning electron microscope (FE-SEM) with energy dispersive X-ray spectroscopy (EDS). Results showed that untreated para rubber leaves consisted mainly of the elements carbon (C) and oxygen (O), accounting for 80.35% and 17.55% by weight, respectively, with minor amounts of other elements. Treated para rubber leaves consisted mainly of C, O, and calcium (Ca) at 69.53%, 28.55%, and 1.25% by weight, respectively. Bulk density and compressive strength of the control cement paste were 1.85 g/cm3 and 47.78 MPa, respectively at 28 days curing. The compressive strength of the cement composite decreased with an increase in the para rubber leaves volume fraction.